14 files changed, 16482 insertions, 0 deletions

diff --git a/drivers/nvme/host/Kconfig b/drivers/nvme/host/Kconfig
new file mode 100644
index 000000000..88a8b5916
--- /dev/null
+++ b/drivers/nvme/host/Kconfig
@@ -0,0 +1,59 @@
+config NVME_CORE
+	tristate
+
+config BLK_DEV_NVME
+	tristate "NVM Express block device"
+	depends on PCI && BLOCK
+	select NVME_CORE
+	---help---
+	  The NVM Express driver is for solid state drives directly
+	  connected to the PCI or PCI Express bus.  If you know you
+	  don't have one of these, it is safe to answer N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called nvme.
+
+config NVME_MULTIPATH
+	bool "NVMe multipath support"
+	depends on NVME_CORE
+	---help---
+	   This option enables support for multipath access to NVMe
+	   subsystems.  If this option is enabled only a single
+	   /dev/nvmeXnY device will show up for each NVMe namespaces,
+	   even if it is accessible through multiple controllers.
+
+config NVME_FABRICS
+	tristate
+
+config NVME_RDMA
+	tristate "NVM Express over Fabrics RDMA host driver"
+	depends on INFINIBAND && INFINIBAND_ADDR_TRANS && BLOCK
+	select NVME_CORE
+	select NVME_FABRICS
+	select SG_POOL
+	help
+	  This provides support for the NVMe over Fabrics protocol using
+	  the RDMA (Infiniband, RoCE, iWarp) transport.  This allows you
+	  to use remote block devices exported using the NVMe protocol set.
+
+	  To configure a NVMe over Fabrics controller use the nvme-cli tool
+	  from https://github.com/linux-nvme/nvme-cli.
+
+	  If unsure, say N.
+
+config NVME_FC
+	tristate "NVM Express over Fabrics FC host driver"
+	depends on BLOCK
+	depends on HAS_DMA
+	select NVME_CORE
+	select NVME_FABRICS
+	select SG_POOL
+	help
+	  This provides support for the NVMe over Fabrics protocol using
+	  the FC transport.  This allows you to use remote block devices
+	  exported using the NVMe protocol set.
+
+	  To configure a NVMe over Fabrics controller use the nvme-cli tool
+	  from https://github.com/linux-nvme/nvme-cli.
+
+	  If unsure, say N.
diff --git a/drivers/nvme/host/Makefile b/drivers/nvme/host/Makefile
new file mode 100644
index 000000000..aea459c65
--- /dev/null
+++ b/drivers/nvme/host/Makefile
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ccflags-y				+= -I$(src)
+
+obj-$(CONFIG_NVME_CORE)			+= nvme-core.o
+obj-$(CONFIG_BLK_DEV_NVME)		+= nvme.o
+obj-$(CONFIG_NVME_FABRICS)		+= nvme-fabrics.o
+obj-$(CONFIG_NVME_RDMA)			+= nvme-rdma.o
+obj-$(CONFIG_NVME_FC)			+= nvme-fc.o
+
+nvme-core-y				:= core.o
+nvme-core-$(CONFIG_TRACING)		+= trace.o
+nvme-core-$(CONFIG_NVME_MULTIPATH)	+= multipath.o
+nvme-core-$(CONFIG_NVM)			+= lightnvm.o
+nvme-core-$(CONFIG_FAULT_INJECTION_DEBUG_FS)	+= fault_inject.o
+
+nvme-y					+= pci.o
+
+nvme-fabrics-y				+= fabrics.o
+
+nvme-rdma-y				+= rdma.o
+
+nvme-fc-y				+= fc.o
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
new file mode 100644
index 000000000..a0a805a5a
--- /dev/null
+++ b/drivers/nvme/host/core.c
@@ -0,0 +1,3875 @@
+/*
+ * NVM Express device driver
+ * Copyright (c) 2011-2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/hdreg.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/list_sort.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/pr.h>
+#include <linux/ptrace.h>
+#include <linux/nvme_ioctl.h>
+#include <linux/t10-pi.h>
+#include <linux/pm_qos.h>
+#include <asm/unaligned.h>
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+#include "nvme.h"
+#include "fabrics.h"
+
+#define NVME_MINORS		(1U << MINORBITS)
+
+unsigned int admin_timeout = 60;
+module_param(admin_timeout, uint, 0644);
+MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
+EXPORT_SYMBOL_GPL(admin_timeout);
+
+unsigned int nvme_io_timeout = 30;
+module_param_named(io_timeout, nvme_io_timeout, uint, 0644);
+MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
+EXPORT_SYMBOL_GPL(nvme_io_timeout);
+
+static unsigned char shutdown_timeout = 5;
+module_param(shutdown_timeout, byte, 0644);
+MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown");
+
+static u8 nvme_max_retries = 5;
+module_param_named(max_retries, nvme_max_retries, byte, 0644);
+MODULE_PARM_DESC(max_retries, "max number of retries a command may have");
+
+static unsigned long default_ps_max_latency_us = 100000;
+module_param(default_ps_max_latency_us, ulong, 0644);
+MODULE_PARM_DESC(default_ps_max_latency_us,
+		 "max power saving latency for new devices; use PM QOS to change per device");
+
+static bool force_apst;
+module_param(force_apst, bool, 0644);
+MODULE_PARM_DESC(force_apst, "allow APST for newly enumerated devices even if quirked off");
+
+static bool streams;
+module_param(streams, bool, 0644);
+MODULE_PARM_DESC(streams, "turn on support for Streams write directives");
+
+/*
+ * nvme_wq - hosts nvme related works that are not reset or delete
+ * nvme_reset_wq - hosts nvme reset works
+ * nvme_delete_wq - hosts nvme delete works
+ *
+ * nvme_wq will host works such are scan, aen handling, fw activation,
+ * keep-alive error recovery, periodic reconnects etc. nvme_reset_wq
+ * runs reset works which also flush works hosted on nvme_wq for
+ * serialization purposes. nvme_delete_wq host controller deletion
+ * works which flush reset works for serialization.
+ */
+struct workqueue_struct *nvme_wq;
+EXPORT_SYMBOL_GPL(nvme_wq);
+
+struct workqueue_struct *nvme_reset_wq;
+EXPORT_SYMBOL_GPL(nvme_reset_wq);
+
+struct workqueue_struct *nvme_delete_wq;
+EXPORT_SYMBOL_GPL(nvme_delete_wq);
+
+static DEFINE_IDA(nvme_subsystems_ida);
+static LIST_HEAD(nvme_subsystems);
+static DEFINE_MUTEX(nvme_subsystems_lock);
+
+static DEFINE_IDA(nvme_instance_ida);
+static dev_t nvme_chr_devt;
+static struct class *nvme_class;
+static struct class *nvme_subsys_class;
+
+static void nvme_ns_remove(struct nvme_ns *ns);
+static int nvme_revalidate_disk(struct gendisk *disk);
+static void nvme_put_subsystem(struct nvme_subsystem *subsys);
+static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
+					   unsigned nsid);
+
+static void nvme_set_queue_dying(struct nvme_ns *ns)
+{
+	/*
+	 * Revalidating a dead namespace sets capacity to 0. This will end
+	 * buffered writers dirtying pages that can't be synced.
+	 */
+	if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags))
+		return;
+	blk_set_queue_dying(ns->queue);
+	/* Forcibly unquiesce queues to avoid blocking dispatch */
+	blk_mq_unquiesce_queue(ns->queue);
+	/*
+	 * Revalidate after unblocking dispatchers that may be holding bd_butex
+	 */
+	revalidate_disk(ns->disk);
+}
+
+static void nvme_queue_scan(struct nvme_ctrl *ctrl)
+{
+	/*
+	 * Only new queue scan work when admin and IO queues are both alive
+	 */
+	if (ctrl->state == NVME_CTRL_LIVE)
+		queue_work(nvme_wq, &ctrl->scan_work);
+}
+
+int nvme_reset_ctrl(struct nvme_ctrl *ctrl)
+{
+	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING))
+		return -EBUSY;
+	if (!queue_work(nvme_reset_wq, &ctrl->reset_work))
+		return -EBUSY;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_reset_ctrl);
+
+int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl)
+{
+	int ret;
+
+	ret = nvme_reset_ctrl(ctrl);
+	if (!ret) {
+		flush_work(&ctrl->reset_work);
+		if (ctrl->state != NVME_CTRL_LIVE &&
+		    ctrl->state != NVME_CTRL_ADMIN_ONLY)
+			ret = -ENETRESET;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_reset_ctrl_sync);
+
+static void nvme_delete_ctrl_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(work, struct nvme_ctrl, delete_work);
+
+	dev_info(ctrl->device,
+		 "Removing ctrl: NQN \"%s\"\n", ctrl->opts->subsysnqn);
+
+	flush_work(&ctrl->reset_work);
+	nvme_stop_ctrl(ctrl);
+	nvme_remove_namespaces(ctrl);
+	ctrl->ops->delete_ctrl(ctrl);
+	nvme_uninit_ctrl(ctrl);
+	nvme_put_ctrl(ctrl);
+}
+
+int nvme_delete_ctrl(struct nvme_ctrl *ctrl)
+{
+	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_DELETING))
+		return -EBUSY;
+	if (!queue_work(nvme_delete_wq, &ctrl->delete_work))
+		return -EBUSY;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_delete_ctrl);
+
+int nvme_delete_ctrl_sync(struct nvme_ctrl *ctrl)
+{
+	int ret = 0;
+
+	/*
+	 * Keep a reference until the work is flushed since ->delete_ctrl
+	 * can free the controller.
+	 */
+	nvme_get_ctrl(ctrl);
+	ret = nvme_delete_ctrl(ctrl);
+	if (!ret)
+		flush_work(&ctrl->delete_work);
+	nvme_put_ctrl(ctrl);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_delete_ctrl_sync);
+
+static inline bool nvme_ns_has_pi(struct nvme_ns *ns)
+{
+	return ns->pi_type && ns->ms == sizeof(struct t10_pi_tuple);
+}
+
+static blk_status_t nvme_error_status(struct request *req)
+{
+	switch (nvme_req(req)->status & 0x7ff) {
+	case NVME_SC_SUCCESS:
+		return BLK_STS_OK;
+	case NVME_SC_CAP_EXCEEDED:
+		return BLK_STS_NOSPC;
+	case NVME_SC_LBA_RANGE:
+		return BLK_STS_TARGET;
+	case NVME_SC_BAD_ATTRIBUTES:
+	case NVME_SC_ONCS_NOT_SUPPORTED:
+	case NVME_SC_INVALID_OPCODE:
+	case NVME_SC_INVALID_FIELD:
+	case NVME_SC_INVALID_NS:
+		return BLK_STS_NOTSUPP;
+	case NVME_SC_WRITE_FAULT:
+	case NVME_SC_READ_ERROR:
+	case NVME_SC_UNWRITTEN_BLOCK:
+	case NVME_SC_ACCESS_DENIED:
+	case NVME_SC_READ_ONLY:
+	case NVME_SC_COMPARE_FAILED:
+		return BLK_STS_MEDIUM;
+	case NVME_SC_GUARD_CHECK:
+	case NVME_SC_APPTAG_CHECK:
+	case NVME_SC_REFTAG_CHECK:
+	case NVME_SC_INVALID_PI:
+		return BLK_STS_PROTECTION;
+	case NVME_SC_RESERVATION_CONFLICT:
+		return BLK_STS_NEXUS;
+	default:
+		return BLK_STS_IOERR;
+	}
+}
+
+static inline bool nvme_req_needs_retry(struct request *req)
+{
+	if (blk_noretry_request(req))
+		return false;
+	if (nvme_req(req)->status & NVME_SC_DNR)
+		return false;
+	if (nvme_req(req)->retries >= nvme_max_retries)
+		return false;
+	return true;
+}
+
+void nvme_complete_rq(struct request *req)
+{
+	blk_status_t status = nvme_error_status(req);
+
+	trace_nvme_complete_rq(req);
+
+	if (unlikely(status != BLK_STS_OK && nvme_req_needs_retry(req))) {
+		if ((req->cmd_flags & REQ_NVME_MPATH) && nvme_failover_req(req))
+			return;
+
+		if (!blk_queue_dying(req->q)) {
+			nvme_req(req)->retries++;
+			blk_mq_requeue_request(req, true);
+			return;
+		}
+	}
+	blk_mq_end_request(req, status);
+}
+EXPORT_SYMBOL_GPL(nvme_complete_rq);
+
+void nvme_cancel_request(struct request *req, void *data, bool reserved)
+{
+	dev_dbg_ratelimited(((struct nvme_ctrl *) data)->device,
+				"Cancelling I/O %d", req->tag);
+
+	nvme_req(req)->status = NVME_SC_ABORT_REQ;
+	blk_mq_complete_request(req);
+
+}
+EXPORT_SYMBOL_GPL(nvme_cancel_request);
+
+bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
+		enum nvme_ctrl_state new_state)
+{
+	enum nvme_ctrl_state old_state;
+	unsigned long flags;
+	bool changed = false;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+
+	old_state = ctrl->state;
+	switch (new_state) {
+	case NVME_CTRL_ADMIN_ONLY:
+		switch (old_state) {
+		case NVME_CTRL_CONNECTING:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	case NVME_CTRL_LIVE:
+		switch (old_state) {
+		case NVME_CTRL_NEW:
+		case NVME_CTRL_RESETTING:
+		case NVME_CTRL_CONNECTING:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	case NVME_CTRL_RESETTING:
+		switch (old_state) {
+		case NVME_CTRL_NEW:
+		case NVME_CTRL_LIVE:
+		case NVME_CTRL_ADMIN_ONLY:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	case NVME_CTRL_CONNECTING:
+		switch (old_state) {
+		case NVME_CTRL_NEW:
+		case NVME_CTRL_RESETTING:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	case NVME_CTRL_DELETING:
+		switch (old_state) {
+		case NVME_CTRL_LIVE:
+		case NVME_CTRL_ADMIN_ONLY:
+		case NVME_CTRL_RESETTING:
+		case NVME_CTRL_CONNECTING:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	case NVME_CTRL_DEAD:
+		switch (old_state) {
+		case NVME_CTRL_DELETING:
+			changed = true;
+			/* FALLTHRU */
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	if (changed)
+		ctrl->state = new_state;
+
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+	if (changed && ctrl->state == NVME_CTRL_LIVE)
+		nvme_kick_requeue_lists(ctrl);
+	return changed;
+}
+EXPORT_SYMBOL_GPL(nvme_change_ctrl_state);
+
+static void nvme_free_ns_head(struct kref *ref)
+{
+	struct nvme_ns_head *head =
+		container_of(ref, struct nvme_ns_head, ref);
+
+	nvme_mpath_remove_disk(head);
+	ida_simple_remove(&head->subsys->ns_ida, head->instance);
+	list_del_init(&head->entry);
+	cleanup_srcu_struct_quiesced(&head->srcu);
+	nvme_put_subsystem(head->subsys);
+	kfree(head);
+}
+
+static void nvme_put_ns_head(struct nvme_ns_head *head)
+{
+	kref_put(&head->ref, nvme_free_ns_head);
+}
+
+static void nvme_free_ns(struct kref *kref)
+{
+	struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
+
+	if (ns->ndev)
+		nvme_nvm_unregister(ns);
+
+	put_disk(ns->disk);
+	nvme_put_ns_head(ns->head);
+	nvme_put_ctrl(ns->ctrl);
+	kfree(ns);
+}
+
+static void nvme_put_ns(struct nvme_ns *ns)
+{
+	kref_put(&ns->kref, nvme_free_ns);
+}
+
+static inline void nvme_clear_nvme_request(struct request *req)
+{
+	if (!(req->rq_flags & RQF_DONTPREP)) {
+		nvme_req(req)->retries = 0;
+		nvme_req(req)->flags = 0;
+		req->rq_flags |= RQF_DONTPREP;
+	}
+}
+
+struct request *nvme_alloc_request(struct request_queue *q,
+		struct nvme_command *cmd, blk_mq_req_flags_t flags, int qid)
+{
+	unsigned op = nvme_is_write(cmd) ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN;
+	struct request *req;
+
+	if (qid == NVME_QID_ANY) {
+		req = blk_mq_alloc_request(q, op, flags);
+	} else {
+		req = blk_mq_alloc_request_hctx(q, op, flags,
+				qid ? qid - 1 : 0);
+	}
+	if (IS_ERR(req))
+		return req;
+
+	req->cmd_flags |= REQ_FAILFAST_DRIVER;
+	nvme_clear_nvme_request(req);
+	nvme_req(req)->cmd = cmd;
+
+	return req;
+}
+EXPORT_SYMBOL_GPL(nvme_alloc_request);
+
+static int nvme_toggle_streams(struct nvme_ctrl *ctrl, bool enable)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+
+	c.directive.opcode = nvme_admin_directive_send;
+	c.directive.nsid = cpu_to_le32(NVME_NSID_ALL);
+	c.directive.doper = NVME_DIR_SND_ID_OP_ENABLE;
+	c.directive.dtype = NVME_DIR_IDENTIFY;
+	c.directive.tdtype = NVME_DIR_STREAMS;
+	c.directive.endir = enable ? NVME_DIR_ENDIR : 0;
+
+	return nvme_submit_sync_cmd(ctrl->admin_q, &c, NULL, 0);
+}
+
+static int nvme_disable_streams(struct nvme_ctrl *ctrl)
+{
+	return nvme_toggle_streams(ctrl, false);
+}
+
+static int nvme_enable_streams(struct nvme_ctrl *ctrl)
+{
+	return nvme_toggle_streams(ctrl, true);
+}
+
+static int nvme_get_stream_params(struct nvme_ctrl *ctrl,
+				  struct streams_directive_params *s, u32 nsid)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	memset(s, 0, sizeof(*s));
+
+	c.directive.opcode = nvme_admin_directive_recv;
+	c.directive.nsid = cpu_to_le32(nsid);
+	c.directive.numd = cpu_to_le32((sizeof(*s) >> 2) - 1);
+	c.directive.doper = NVME_DIR_RCV_ST_OP_PARAM;
+	c.directive.dtype = NVME_DIR_STREAMS;
+
+	return nvme_submit_sync_cmd(ctrl->admin_q, &c, s, sizeof(*s));
+}
+
+static int nvme_configure_directives(struct nvme_ctrl *ctrl)
+{
+	struct streams_directive_params s;
+	int ret;
+
+	if (!(ctrl->oacs & NVME_CTRL_OACS_DIRECTIVES))
+		return 0;
+	if (!streams)
+		return 0;
+
+	ret = nvme_enable_streams(ctrl);
+	if (ret)
+		return ret;
+
+	ret = nvme_get_stream_params(ctrl, &s, NVME_NSID_ALL);
+	if (ret)
+		return ret;
+
+	ctrl->nssa = le16_to_cpu(s.nssa);
+	if (ctrl->nssa < BLK_MAX_WRITE_HINTS - 1) {
+		dev_info(ctrl->device, "too few streams (%u) available\n",
+					ctrl->nssa);
+		nvme_disable_streams(ctrl);
+		return 0;
+	}
+
+	ctrl->nr_streams = min_t(unsigned, ctrl->nssa, BLK_MAX_WRITE_HINTS - 1);
+	dev_info(ctrl->device, "Using %u streams\n", ctrl->nr_streams);
+	return 0;
+}
+
+/*
+ * Check if 'req' has a write hint associated with it. If it does, assign
+ * a valid namespace stream to the write.
+ */
+static void nvme_assign_write_stream(struct nvme_ctrl *ctrl,
+				     struct request *req, u16 *control,
+				     u32 *dsmgmt)
+{
+	enum rw_hint streamid = req->write_hint;
+
+	if (streamid == WRITE_LIFE_NOT_SET || streamid == WRITE_LIFE_NONE)
+		streamid = 0;
+	else {
+		streamid--;
+		if (WARN_ON_ONCE(streamid > ctrl->nr_streams))
+			return;
+
+		*control |= NVME_RW_DTYPE_STREAMS;
+		*dsmgmt |= streamid << 16;
+	}
+
+	if (streamid < ARRAY_SIZE(req->q->write_hints))
+		req->q->write_hints[streamid] += blk_rq_bytes(req) >> 9;
+}
+
+static inline void nvme_setup_flush(struct nvme_ns *ns,
+		struct nvme_command *cmnd)
+{
+	memset(cmnd, 0, sizeof(*cmnd));
+	cmnd->common.opcode = nvme_cmd_flush;
+	cmnd->common.nsid = cpu_to_le32(ns->head->ns_id);
+}
+
+static blk_status_t nvme_setup_discard(struct nvme_ns *ns, struct request *req,
+		struct nvme_command *cmnd)
+{
+	unsigned short segments = blk_rq_nr_discard_segments(req), n = 0;
+	struct nvme_dsm_range *range;
+	struct bio *bio;
+
+	/*
+	 * Some devices do not consider the DSM 'Number of Ranges' field when
+	 * determining how much data to DMA. Always allocate memory for maximum
+	 * number of segments to prevent device reading beyond end of buffer.
+	 */
+	static const size_t alloc_size = sizeof(*range) * NVME_DSM_MAX_RANGES;
+
+	range = kzalloc(alloc_size, GFP_ATOMIC | __GFP_NOWARN);
+	if (!range) {
+		/*
+		 * If we fail allocation our range, fallback to the controller
+		 * discard page. If that's also busy, it's safe to return
+		 * busy, as we know we can make progress once that's freed.
+		 */
+		if (test_and_set_bit_lock(0, &ns->ctrl->discard_page_busy))
+			return BLK_STS_RESOURCE;
+
+		range = page_address(ns->ctrl->discard_page);
+	}
+
+	__rq_for_each_bio(bio, req) {
+		u64 slba = nvme_block_nr(ns, bio->bi_iter.bi_sector);
+		u32 nlb = bio->bi_iter.bi_size >> ns->lba_shift;
+
+		if (n < segments) {
+			range[n].cattr = cpu_to_le32(0);
+			range[n].nlb = cpu_to_le32(nlb);
+			range[n].slba = cpu_to_le64(slba);
+		}
+		n++;
+	}
+
+	if (WARN_ON_ONCE(n != segments)) {
+		if (virt_to_page(range) == ns->ctrl->discard_page)
+			clear_bit_unlock(0, &ns->ctrl->discard_page_busy);
+		else
+			kfree(range);
+		return BLK_STS_IOERR;
+	}
+
+	memset(cmnd, 0, sizeof(*cmnd));
+	cmnd->dsm.opcode = nvme_cmd_dsm;
+	cmnd->dsm.nsid = cpu_to_le32(ns->head->ns_id);
+	cmnd->dsm.nr = cpu_to_le32(segments - 1);
+	cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
+
+	req->special_vec.bv_page = virt_to_page(range);
+	req->special_vec.bv_offset = offset_in_page(range);
+	req->special_vec.bv_len = alloc_size;
+	req->rq_flags |= RQF_SPECIAL_PAYLOAD;
+
+	return BLK_STS_OK;
+}
+
+static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
+		struct request *req, struct nvme_command *cmnd)
+{
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	u16 control = 0;
+	u32 dsmgmt = 0;
+
+	if (req->cmd_flags & REQ_FUA)
+		control |= NVME_RW_FUA;
+	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
+		control |= NVME_RW_LR;
+
+	if (req->cmd_flags & REQ_RAHEAD)
+		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
+
+	memset(cmnd, 0, sizeof(*cmnd));
+	cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
+	cmnd->rw.nsid = cpu_to_le32(ns->head->ns_id);
+	cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
+	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
+
+	if (req_op(req) == REQ_OP_WRITE && ctrl->nr_streams)
+		nvme_assign_write_stream(ctrl, req, &control, &dsmgmt);
+
+	if (ns->ms) {
+		/*
+		 * If formated with metadata, the block layer always provides a
+		 * metadata buffer if CONFIG_BLK_DEV_INTEGRITY is enabled.  Else
+		 * we enable the PRACT bit for protection information or set the
+		 * namespace capacity to zero to prevent any I/O.
+		 */
+		if (!blk_integrity_rq(req)) {
+			if (WARN_ON_ONCE(!nvme_ns_has_pi(ns)))
+				return BLK_STS_NOTSUPP;
+			control |= NVME_RW_PRINFO_PRACT;
+		} else if (req_op(req) == REQ_OP_WRITE) {
+			t10_pi_prepare(req, ns->pi_type);
+		}
+
+		switch (ns->pi_type) {
+		case NVME_NS_DPS_PI_TYPE3:
+			control |= NVME_RW_PRINFO_PRCHK_GUARD;
+			break;
+		case NVME_NS_DPS_PI_TYPE1:
+		case NVME_NS_DPS_PI_TYPE2:
+			control |= NVME_RW_PRINFO_PRCHK_GUARD |
+					NVME_RW_PRINFO_PRCHK_REF;
+			cmnd->rw.reftag = cpu_to_le32(t10_pi_ref_tag(req));
+			break;
+		}
+	}
+
+	cmnd->rw.control = cpu_to_le16(control);
+	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
+	return 0;
+}
+
+void nvme_cleanup_cmd(struct request *req)
+{
+	if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ &&
+	    nvme_req(req)->status == 0) {
+		struct nvme_ns *ns = req->rq_disk->private_data;
+
+		t10_pi_complete(req, ns->pi_type,
+				blk_rq_bytes(req) >> ns->lba_shift);
+	}
+	if (req->rq_flags & RQF_SPECIAL_PAYLOAD) {
+		struct nvme_ns *ns = req->rq_disk->private_data;
+		struct page *page = req->special_vec.bv_page;
+
+		if (page == ns->ctrl->discard_page)
+			clear_bit_unlock(0, &ns->ctrl->discard_page_busy);
+		else
+			kfree(page_address(page) + req->special_vec.bv_offset);
+	}
+}
+EXPORT_SYMBOL_GPL(nvme_cleanup_cmd);
+
+blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
+		struct nvme_command *cmd)
+{
+	blk_status_t ret = BLK_STS_OK;
+
+	nvme_clear_nvme_request(req);
+
+	switch (req_op(req)) {
+	case REQ_OP_DRV_IN:
+	case REQ_OP_DRV_OUT:
+		memcpy(cmd, nvme_req(req)->cmd, sizeof(*cmd));
+		break;
+	case REQ_OP_FLUSH:
+		nvme_setup_flush(ns, cmd);
+		break;
+	case REQ_OP_WRITE_ZEROES:
+		/* currently only aliased to deallocate for a few ctrls: */
+	case REQ_OP_DISCARD:
+		ret = nvme_setup_discard(ns, req, cmd);
+		break;
+	case REQ_OP_READ:
+	case REQ_OP_WRITE:
+		ret = nvme_setup_rw(ns, req, cmd);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return BLK_STS_IOERR;
+	}
+
+	cmd->common.command_id = req->tag;
+	trace_nvme_setup_cmd(req, cmd);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_setup_cmd);
+
+/*
+ * Returns 0 on success.  If the result is negative, it's a Linux error code;
+ * if the result is positive, it's an NVM Express status code
+ */
+int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
+		union nvme_result *result, void *buffer, unsigned bufflen,
+		unsigned timeout, int qid, int at_head,
+		blk_mq_req_flags_t flags)
+{
+	struct request *req;
+	int ret;
+
+	req = nvme_alloc_request(q, cmd, flags, qid);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
+
+	if (buffer && bufflen) {
+		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
+		if (ret)
+			goto out;
+	}
+
+	blk_execute_rq(req->q, NULL, req, at_head);
+	if (result)
+		*result = nvme_req(req)->result;
+	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
+		ret = -EINTR;
+	else
+		ret = nvme_req(req)->status;
+ out:
+	blk_mq_free_request(req);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(__nvme_submit_sync_cmd);
+
+int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
+		void *buffer, unsigned bufflen)
+{
+	return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0,
+			NVME_QID_ANY, 0, 0);
+}
+EXPORT_SYMBOL_GPL(nvme_submit_sync_cmd);
+
+static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
+		unsigned len, u32 seed, bool write)
+{
+	struct bio_integrity_payload *bip;
+	int ret = -ENOMEM;
+	void *buf;
+
+	buf = kmalloc(len, GFP_KERNEL);
+	if (!buf)
+		goto out;
+
+	ret = -EFAULT;
+	if (write && copy_from_user(buf, ubuf, len))
+		goto out_free_meta;
+
+	bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
+	if (IS_ERR(bip)) {
+		ret = PTR_ERR(bip);
+		goto out_free_meta;
+	}
+
+	bip->bip_iter.bi_size = len;
+	bip->bip_iter.bi_sector = seed;
+	ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
+			offset_in_page(buf));
+	if (ret == len)
+		return buf;
+	ret = -ENOMEM;
+out_free_meta:
+	kfree(buf);
+out:
+	return ERR_PTR(ret);
+}
+
+static int nvme_submit_user_cmd(struct request_queue *q,
+		struct nvme_command *cmd, void __user *ubuffer,
+		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
+		u32 meta_seed, u32 *result, unsigned timeout)
+{
+	bool write = nvme_is_write(cmd);
+	struct nvme_ns *ns = q->queuedata;
+	struct gendisk *disk = ns ? ns->disk : NULL;
+	struct request *req;
+	struct bio *bio = NULL;
+	void *meta = NULL;
+	int ret;
+
+	req = nvme_alloc_request(q, cmd, 0, NVME_QID_ANY);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
+	nvme_req(req)->flags |= NVME_REQ_USERCMD;
+
+	if (ubuffer && bufflen) {
+		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
+				GFP_KERNEL);
+		if (ret)
+			goto out;
+		bio = req->bio;
+		bio->bi_disk = disk;
+		if (disk && meta_buffer && meta_len) {
+			meta = nvme_add_user_metadata(bio, meta_buffer, meta_len,
+					meta_seed, write);
+			if (IS_ERR(meta)) {
+				ret = PTR_ERR(meta);
+				goto out_unmap;
+			}
+			req->cmd_flags |= REQ_INTEGRITY;
+		}
+	}
+
+	blk_execute_rq(req->q, disk, req, 0);
+	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
+		ret = -EINTR;
+	else
+		ret = nvme_req(req)->status;
+	if (result)
+		*result = le32_to_cpu(nvme_req(req)->result.u32);
+	if (meta && !ret && !write) {
+		if (copy_to_user(meta_buffer, meta, meta_len))
+			ret = -EFAULT;
+	}
+	kfree(meta);
+ out_unmap:
+	if (bio)
+		blk_rq_unmap_user(bio);
+ out:
+	blk_mq_free_request(req);
+	return ret;
+}
+
+static void nvme_keep_alive_end_io(struct request *rq, blk_status_t status)
+{
+	struct nvme_ctrl *ctrl = rq->end_io_data;
+	unsigned long flags;
+	bool startka = false;
+
+	blk_mq_free_request(rq);
+
+	if (status) {
+		dev_err(ctrl->device,
+			"failed nvme_keep_alive_end_io error=%d\n",
+				status);
+		return;
+	}
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	if (ctrl->state == NVME_CTRL_LIVE ||
+	    ctrl->state == NVME_CTRL_CONNECTING)
+		startka = true;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+	if (startka)
+		schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
+}
+
+static int nvme_keep_alive(struct nvme_ctrl *ctrl)
+{
+	struct request *rq;
+
+	rq = nvme_alloc_request(ctrl->admin_q, &ctrl->ka_cmd, BLK_MQ_REQ_RESERVED,
+			NVME_QID_ANY);
+	if (IS_ERR(rq))
+		return PTR_ERR(rq);
+
+	rq->timeout = ctrl->kato * HZ;
+	rq->end_io_data = ctrl;
+
+	blk_execute_rq_nowait(rq->q, NULL, rq, 0, nvme_keep_alive_end_io);
+
+	return 0;
+}
+
+static void nvme_keep_alive_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl = container_of(to_delayed_work(work),
+			struct nvme_ctrl, ka_work);
+
+	if (nvme_keep_alive(ctrl)) {
+		/* allocation failure, reset the controller */
+		dev_err(ctrl->device, "keep-alive failed\n");
+		nvme_reset_ctrl(ctrl);
+		return;
+	}
+}
+
+static void nvme_start_keep_alive(struct nvme_ctrl *ctrl)
+{
+	if (unlikely(ctrl->kato == 0))
+		return;
+
+	schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
+}
+
+void nvme_stop_keep_alive(struct nvme_ctrl *ctrl)
+{
+	if (unlikely(ctrl->kato == 0))
+		return;
+
+	cancel_delayed_work_sync(&ctrl->ka_work);
+}
+EXPORT_SYMBOL_GPL(nvme_stop_keep_alive);
+
+/*
+ * In NVMe 1.0 the CNS field was just a binary controller or namespace
+ * flag, thus sending any new CNS opcodes has a big chance of not working.
+ * Qemu unfortunately had that bug after reporting a 1.1 version compliance
+ * (but not for any later version).
+ */
+static bool nvme_ctrl_limited_cns(struct nvme_ctrl *ctrl)
+{
+	if (ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)
+		return ctrl->vs < NVME_VS(1, 2, 0);
+	return ctrl->vs < NVME_VS(1, 1, 0);
+}
+
+static int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
+{
+	struct nvme_command c = { };
+	int error;
+
+	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.cns = NVME_ID_CNS_CTRL;
+
+	*id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
+	if (!*id)
+		return -ENOMEM;
+
+	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
+			sizeof(struct nvme_id_ctrl));
+	if (error)
+		kfree(*id);
+	return error;
+}
+
+static int nvme_identify_ns_descs(struct nvme_ctrl *ctrl, unsigned nsid,
+		struct nvme_ns_ids *ids)
+{
+	struct nvme_command c = { };
+	int status;
+	void *data;
+	int pos;
+	int len;
+
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.nsid = cpu_to_le32(nsid);
+	c.identify.cns = NVME_ID_CNS_NS_DESC_LIST;
+
+	data = kzalloc(NVME_IDENTIFY_DATA_SIZE, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	status = nvme_submit_sync_cmd(ctrl->admin_q, &c, data,
+				      NVME_IDENTIFY_DATA_SIZE);
+	if (status)
+		goto free_data;
+
+	for (pos = 0; pos < NVME_IDENTIFY_DATA_SIZE; pos += len) {
+		struct nvme_ns_id_desc *cur = data + pos;
+
+		if (cur->nidl == 0)
+			break;
+
+		switch (cur->nidt) {
+		case NVME_NIDT_EUI64:
+			if (cur->nidl != NVME_NIDT_EUI64_LEN) {
+				dev_warn(ctrl->device,
+					 "ctrl returned bogus length: %d for NVME_NIDT_EUI64\n",
+					 cur->nidl);
+				goto free_data;
+			}
+			len = NVME_NIDT_EUI64_LEN;
+			memcpy(ids->eui64, data + pos + sizeof(*cur), len);
+			break;
+		case NVME_NIDT_NGUID:
+			if (cur->nidl != NVME_NIDT_NGUID_LEN) {
+				dev_warn(ctrl->device,
+					 "ctrl returned bogus length: %d for NVME_NIDT_NGUID\n",
+					 cur->nidl);
+				goto free_data;
+			}
+			len = NVME_NIDT_NGUID_LEN;
+			memcpy(ids->nguid, data + pos + sizeof(*cur), len);
+			break;
+		case NVME_NIDT_UUID:
+			if (cur->nidl != NVME_NIDT_UUID_LEN) {
+				dev_warn(ctrl->device,
+					 "ctrl returned bogus length: %d for NVME_NIDT_UUID\n",
+					 cur->nidl);
+				goto free_data;
+			}
+			len = NVME_NIDT_UUID_LEN;
+			uuid_copy(&ids->uuid, data + pos + sizeof(*cur));
+			break;
+		default:
+			/* Skip unnkown types */
+			len = cur->nidl;
+			break;
+		}
+
+		len += sizeof(*cur);
+	}
+free_data:
+	kfree(data);
+	return status;
+}
+
+static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
+{
+	struct nvme_command c = { };
+
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.cns = NVME_ID_CNS_NS_ACTIVE_LIST;
+	c.identify.nsid = cpu_to_le32(nsid);
+	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list,
+				    NVME_IDENTIFY_DATA_SIZE);
+}
+
+static struct nvme_id_ns *nvme_identify_ns(struct nvme_ctrl *ctrl,
+		unsigned nsid)
+{
+	struct nvme_id_ns *id;
+	struct nvme_command c = { };
+	int error;
+
+	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.nsid = cpu_to_le32(nsid);
+	c.identify.cns = NVME_ID_CNS_NS;
+
+	id = kmalloc(sizeof(*id), GFP_KERNEL);
+	if (!id)
+		return NULL;
+
+	error = nvme_submit_sync_cmd(ctrl->admin_q, &c, id, sizeof(*id));
+	if (error) {
+		dev_warn(ctrl->device, "Identify namespace failed\n");
+		kfree(id);
+		return NULL;
+	}
+
+	return id;
+}
+
+static int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
+		      void *buffer, size_t buflen, u32 *result)
+{
+	union nvme_result res = { 0 };
+	struct nvme_command c;
+	int ret;
+
+	memset(&c, 0, sizeof(c));
+	c.features.opcode = nvme_admin_set_features;
+	c.features.fid = cpu_to_le32(fid);
+	c.features.dword11 = cpu_to_le32(dword11);
+
+	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &res,
+			buffer, buflen, 0, NVME_QID_ANY, 0, 0);
+	if (ret >= 0 && result)
+		*result = le32_to_cpu(res.u32);
+	return ret;
+}
+
+int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
+{
+	u32 q_count = (*count - 1) | ((*count - 1) << 16);
+	u32 result;
+	int status, nr_io_queues;
+
+	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, NULL, 0,
+			&result);
+	if (status < 0)
+		return status;
+
+	/*
+	 * Degraded controllers might return an error when setting the queue
+	 * count.  We still want to be able to bring them online and offer
+	 * access to the admin queue, as that might be only way to fix them up.
+	 */
+	if (status > 0) {
+		dev_err(ctrl->device, "Could not set queue count (%d)\n", status);
+		*count = 0;
+	} else {
+		nr_io_queues = min(result & 0xffff, result >> 16) + 1;
+		*count = min(*count, nr_io_queues);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_set_queue_count);
+
+#define NVME_AEN_SUPPORTED \
+	(NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_FW_ACT | NVME_AEN_CFG_ANA_CHANGE)
+
+static void nvme_enable_aen(struct nvme_ctrl *ctrl)
+{
+	u32 result, supported_aens = ctrl->oaes & NVME_AEN_SUPPORTED;
+	int status;
+
+	if (!supported_aens)
+		return;
+
+	status = nvme_set_features(ctrl, NVME_FEAT_ASYNC_EVENT, supported_aens,
+			NULL, 0, &result);
+	if (status)
+		dev_warn(ctrl->device, "Failed to configure AEN (cfg %x)\n",
+			 supported_aens);
+}
+
+static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
+{
+	struct nvme_user_io io;
+	struct nvme_command c;
+	unsigned length, meta_len;
+	void __user *metadata;
+
+	if (copy_from_user(&io, uio, sizeof(io)))
+		return -EFAULT;
+	if (io.flags)
+		return -EINVAL;
+
+	switch (io.opcode) {
+	case nvme_cmd_write:
+	case nvme_cmd_read:
+	case nvme_cmd_compare:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	length = (io.nblocks + 1) << ns->lba_shift;
+	meta_len = (io.nblocks + 1) * ns->ms;
+	metadata = (void __user *)(uintptr_t)io.metadata;
+
+	if (ns->ext) {
+		length += meta_len;
+		meta_len = 0;
+	} else if (meta_len) {
+		if ((io.metadata & 3) || !io.metadata)
+			return -EINVAL;
+	}
+
+	memset(&c, 0, sizeof(c));
+	c.rw.opcode = io.opcode;
+	c.rw.flags = io.flags;
+	c.rw.nsid = cpu_to_le32(ns->head->ns_id);
+	c.rw.slba = cpu_to_le64(io.slba);
+	c.rw.length = cpu_to_le16(io.nblocks);
+	c.rw.control = cpu_to_le16(io.control);
+	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
+	c.rw.reftag = cpu_to_le32(io.reftag);
+	c.rw.apptag = cpu_to_le16(io.apptag);
+	c.rw.appmask = cpu_to_le16(io.appmask);
+
+	return nvme_submit_user_cmd(ns->queue, &c,
+			(void __user *)(uintptr_t)io.addr, length,
+			metadata, meta_len, io.slba, NULL, 0);
+}
+
+static u32 nvme_known_admin_effects(u8 opcode)
+{
+	switch (opcode) {
+	case nvme_admin_format_nvm:
+		return NVME_CMD_EFFECTS_CSUPP | NVME_CMD_EFFECTS_LBCC |
+					NVME_CMD_EFFECTS_CSE_MASK;
+	case nvme_admin_sanitize_nvm:
+		return NVME_CMD_EFFECTS_CSE_MASK;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static u32 nvme_passthru_start(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
+								u8 opcode)
+{
+	u32 effects = 0;
+
+	if (ns) {
+		if (ctrl->effects)
+			effects = le32_to_cpu(ctrl->effects->iocs[opcode]);
+		if (effects & ~NVME_CMD_EFFECTS_CSUPP)
+			dev_warn(ctrl->device,
+				 "IO command:%02x has unhandled effects:%08x\n",
+				 opcode, effects);
+		return 0;
+	}
+
+	if (ctrl->effects)
+		effects = le32_to_cpu(ctrl->effects->acs[opcode]);
+	else
+		effects = nvme_known_admin_effects(opcode);
+
+	/*
+	 * For simplicity, IO to all namespaces is quiesced even if the command
+	 * effects say only one namespace is affected.
+	 */
+	if (effects & (NVME_CMD_EFFECTS_LBCC | NVME_CMD_EFFECTS_CSE_MASK)) {
+		mutex_lock(&ctrl->scan_lock);
+		mutex_lock(&ctrl->subsys->lock);
+		nvme_mpath_start_freeze(ctrl->subsys);
+		nvme_mpath_wait_freeze(ctrl->subsys);
+		nvme_start_freeze(ctrl);
+		nvme_wait_freeze(ctrl);
+	}
+	return effects;
+}
+
+static void nvme_update_formats(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		if (ns->disk && nvme_revalidate_disk(ns->disk))
+			nvme_set_queue_dying(ns);
+	up_read(&ctrl->namespaces_rwsem);
+
+	nvme_remove_invalid_namespaces(ctrl, NVME_NSID_ALL);
+}
+
+static void nvme_passthru_end(struct nvme_ctrl *ctrl, u32 effects)
+{
+	/*
+	 * Revalidate LBA changes prior to unfreezing. This is necessary to
+	 * prevent memory corruption if a logical block size was changed by
+	 * this command.
+	 */
+	if (effects & NVME_CMD_EFFECTS_LBCC)
+		nvme_update_formats(ctrl);
+	if (effects & (NVME_CMD_EFFECTS_LBCC | NVME_CMD_EFFECTS_CSE_MASK)) {
+		nvme_unfreeze(ctrl);
+		nvme_mpath_unfreeze(ctrl->subsys);
+		mutex_unlock(&ctrl->subsys->lock);
+		mutex_unlock(&ctrl->scan_lock);
+	}
+	if (effects & NVME_CMD_EFFECTS_CCC)
+		nvme_init_identify(ctrl);
+	if (effects & (NVME_CMD_EFFECTS_NIC | NVME_CMD_EFFECTS_NCC))
+		nvme_queue_scan(ctrl);
+}
+
+static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
+			struct nvme_passthru_cmd __user *ucmd)
+{
+	struct nvme_passthru_cmd cmd;
+	struct nvme_command c;
+	unsigned timeout = 0;
+	u32 effects;
+	int status;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
+		return -EFAULT;
+	if (cmd.flags)
+		return -EINVAL;
+
+	memset(&c, 0, sizeof(c));
+	c.common.opcode = cmd.opcode;
+	c.common.flags = cmd.flags;
+	c.common.nsid = cpu_to_le32(cmd.nsid);
+	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
+	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
+	c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
+	c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
+	c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
+	c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
+	c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
+	c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
+
+	if (cmd.timeout_ms)
+		timeout = msecs_to_jiffies(cmd.timeout_ms);
+
+	effects = nvme_passthru_start(ctrl, ns, cmd.opcode);
+	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
+			(void __user *)(uintptr_t)cmd.addr, cmd.data_len,
+			(void __user *)(uintptr_t)cmd.metadata, cmd.metadata_len,
+			0, &cmd.result, timeout);
+	nvme_passthru_end(ctrl, effects);
+
+	if (status >= 0) {
+		if (put_user(cmd.result, &ucmd->result))
+			return -EFAULT;
+	}
+
+	return status;
+}
+
+/*
+ * Issue ioctl requests on the first available path.  Note that unlike normal
+ * block layer requests we will not retry failed request on another controller.
+ */
+static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk,
+		struct nvme_ns_head **head, int *srcu_idx)
+{
+#ifdef CONFIG_NVME_MULTIPATH
+	if (disk->fops == &nvme_ns_head_ops) {
+		struct nvme_ns *ns;
+
+		*head = disk->private_data;
+		*srcu_idx = srcu_read_lock(&(*head)->srcu);
+		ns = nvme_find_path(*head);
+		if (!ns)
+			srcu_read_unlock(&(*head)->srcu, *srcu_idx);
+		return ns;
+	}
+#endif
+	*head = NULL;
+	*srcu_idx = -1;
+	return disk->private_data;
+}
+
+static void nvme_put_ns_from_disk(struct nvme_ns_head *head, int idx)
+{
+	if (head)
+		srcu_read_unlock(&head->srcu, idx);
+}
+
+static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
+		unsigned int cmd, unsigned long arg)
+{
+	struct nvme_ns_head *head = NULL;
+	void __user *argp = (void __user *)arg;
+	struct nvme_ns *ns;
+	int srcu_idx, ret;
+
+	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
+	if (unlikely(!ns))
+		return -EWOULDBLOCK;
+
+	/*
+	 * Handle ioctls that apply to the controller instead of the namespace
+	 * seperately and drop the ns SRCU reference early.  This avoids a
+	 * deadlock when deleting namespaces using the passthrough interface.
+	 */
+	if (cmd == NVME_IOCTL_ADMIN_CMD || is_sed_ioctl(cmd)) {
+		struct nvme_ctrl *ctrl = ns->ctrl;
+
+		nvme_get_ctrl(ns->ctrl);
+		nvme_put_ns_from_disk(head, srcu_idx);
+
+		if (cmd == NVME_IOCTL_ADMIN_CMD)
+			ret = nvme_user_cmd(ctrl, NULL, argp);
+		else
+			ret = sed_ioctl(ctrl->opal_dev, cmd, argp);
+
+		nvme_put_ctrl(ctrl);
+		return ret;
+	}
+
+	switch (cmd) {
+	case NVME_IOCTL_ID:
+		force_successful_syscall_return();
+		ret = ns->head->ns_id;
+		break;
+	case NVME_IOCTL_IO_CMD:
+		ret = nvme_user_cmd(ns->ctrl, ns, argp);
+		break;
+	case NVME_IOCTL_SUBMIT_IO:
+		ret = nvme_submit_io(ns, argp);
+		break;
+	default:
+		if (ns->ndev)
+			ret = nvme_nvm_ioctl(ns, cmd, arg);
+		else
+			ret = -ENOTTY;
+	}
+
+	nvme_put_ns_from_disk(head, srcu_idx);
+	return ret;
+}
+
+static int nvme_open(struct block_device *bdev, fmode_t mode)
+{
+	struct nvme_ns *ns = bdev->bd_disk->private_data;
+
+#ifdef CONFIG_NVME_MULTIPATH
+	/* should never be called due to GENHD_FL_HIDDEN */
+	if (WARN_ON_ONCE(ns->head->disk))
+		goto fail;
+#endif
+	if (!kref_get_unless_zero(&ns->kref))
+		goto fail;
+	if (!try_module_get(ns->ctrl->ops->module))
+		goto fail_put_ns;
+
+	return 0;
+
+fail_put_ns:
+	nvme_put_ns(ns);
+fail:
+	return -ENXIO;
+}
+
+static void nvme_release(struct gendisk *disk, fmode_t mode)
+{
+	struct nvme_ns *ns = disk->private_data;
+
+	module_put(ns->ctrl->ops->module);
+	nvme_put_ns(ns);
+}
+
+static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	/* some standard values */
+	geo->heads = 1 << 6;
+	geo->sectors = 1 << 5;
+	geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
+	return 0;
+}
+
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+static void nvme_init_integrity(struct gendisk *disk, u16 ms, u8 pi_type)
+{
+	struct blk_integrity integrity;
+
+	memset(&integrity, 0, sizeof(integrity));
+	switch (pi_type) {
+	case NVME_NS_DPS_PI_TYPE3:
+		integrity.profile = &t10_pi_type3_crc;
+		integrity.tag_size = sizeof(u16) + sizeof(u32);
+		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
+		break;
+	case NVME_NS_DPS_PI_TYPE1:
+	case NVME_NS_DPS_PI_TYPE2:
+		integrity.profile = &t10_pi_type1_crc;
+		integrity.tag_size = sizeof(u16);
+		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
+		break;
+	default:
+		integrity.profile = NULL;
+		break;
+	}
+	integrity.tuple_size = ms;
+	blk_integrity_register(disk, &integrity);
+	blk_queue_max_integrity_segments(disk->queue, 1);
+}
+#else
+static void nvme_init_integrity(struct gendisk *disk, u16 ms, u8 pi_type)
+{
+}
+#endif /* CONFIG_BLK_DEV_INTEGRITY */
+
+static void nvme_set_chunk_size(struct nvme_ns *ns)
+{
+	u32 chunk_size = (((u32)ns->noiob) << (ns->lba_shift - 9));
+	blk_queue_chunk_sectors(ns->queue, rounddown_pow_of_two(chunk_size));
+}
+
+static void nvme_config_discard(struct nvme_ns *ns)
+{
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct request_queue *queue = ns->queue;
+	u32 size = queue_logical_block_size(queue);
+
+	if (!(ctrl->oncs & NVME_CTRL_ONCS_DSM)) {
+		blk_queue_flag_clear(QUEUE_FLAG_DISCARD, queue);
+		return;
+	}
+
+	if (ctrl->nr_streams && ns->sws && ns->sgs)
+		size *= ns->sws * ns->sgs;
+
+	BUILD_BUG_ON(PAGE_SIZE / sizeof(struct nvme_dsm_range) <
+			NVME_DSM_MAX_RANGES);
+
+	queue->limits.discard_alignment = 0;
+	queue->limits.discard_granularity = size;
+
+	/* If discard is already enabled, don't reset queue limits */
+	if (blk_queue_flag_test_and_set(QUEUE_FLAG_DISCARD, queue))
+		return;
+
+	blk_queue_max_discard_sectors(queue, UINT_MAX);
+	blk_queue_max_discard_segments(queue, NVME_DSM_MAX_RANGES);
+
+	if (ctrl->quirks & NVME_QUIRK_DEALLOCATE_ZEROES)
+		blk_queue_max_write_zeroes_sectors(queue, UINT_MAX);
+}
+
+static void nvme_report_ns_ids(struct nvme_ctrl *ctrl, unsigned int nsid,
+		struct nvme_id_ns *id, struct nvme_ns_ids *ids)
+{
+	memset(ids, 0, sizeof(*ids));
+
+	if (ctrl->vs >= NVME_VS(1, 1, 0))
+		memcpy(ids->eui64, id->eui64, sizeof(id->eui64));
+	if (ctrl->vs >= NVME_VS(1, 2, 0))
+		memcpy(ids->nguid, id->nguid, sizeof(id->nguid));
+	if (ctrl->vs >= NVME_VS(1, 3, 0)) {
+		 /* Don't treat error as fatal we potentially
+		  * already have a NGUID or EUI-64
+		  */
+		if (nvme_identify_ns_descs(ctrl, nsid, ids))
+			dev_warn(ctrl->device,
+				 "%s: Identify Descriptors failed\n", __func__);
+	}
+}
+
+static bool nvme_ns_ids_valid(struct nvme_ns_ids *ids)
+{
+	return !uuid_is_null(&ids->uuid) ||
+		memchr_inv(ids->nguid, 0, sizeof(ids->nguid)) ||
+		memchr_inv(ids->eui64, 0, sizeof(ids->eui64));
+}
+
+static bool nvme_ns_ids_equal(struct nvme_ns_ids *a, struct nvme_ns_ids *b)
+{
+	return uuid_equal(&a->uuid, &b->uuid) &&
+		memcmp(&a->nguid, &b->nguid, sizeof(a->nguid)) == 0 &&
+		memcmp(&a->eui64, &b->eui64, sizeof(a->eui64)) == 0;
+}
+
+static void nvme_update_disk_info(struct gendisk *disk,
+		struct nvme_ns *ns, struct nvme_id_ns *id)
+{
+	sector_t capacity = le64_to_cpup(&id->nsze) << (ns->lba_shift - 9);
+	unsigned short bs = 1 << ns->lba_shift;
+
+	if (ns->lba_shift > PAGE_SHIFT) {
+		/* unsupported block size, set capacity to 0 later */
+		bs = (1 << 9);
+	}
+	blk_mq_freeze_queue(disk->queue);
+	blk_integrity_unregister(disk);
+
+	blk_queue_logical_block_size(disk->queue, bs);
+	blk_queue_physical_block_size(disk->queue, bs);
+	blk_queue_io_min(disk->queue, bs);
+
+	if (ns->ms && !ns->ext &&
+	    (ns->ctrl->ops->flags & NVME_F_METADATA_SUPPORTED))
+		nvme_init_integrity(disk, ns->ms, ns->pi_type);
+	if ((ns->ms && !nvme_ns_has_pi(ns) && !blk_get_integrity(disk)) ||
+	    ns->lba_shift > PAGE_SHIFT)
+		capacity = 0;
+
+	set_capacity(disk, capacity);
+	nvme_config_discard(ns);
+
+	if (id->nsattr & (1 << 0))
+		set_disk_ro(disk, true);
+	else
+		set_disk_ro(disk, false);
+
+	blk_mq_unfreeze_queue(disk->queue);
+}
+
+static void __nvme_revalidate_disk(struct gendisk *disk, struct nvme_id_ns *id)
+{
+	struct nvme_ns *ns = disk->private_data;
+
+	/*
+	 * If identify namespace failed, use default 512 byte block size so
+	 * block layer can use before failing read/write for 0 capacity.
+	 */
+	ns->lba_shift = id->lbaf[id->flbas & NVME_NS_FLBAS_LBA_MASK].ds;
+	if (ns->lba_shift == 0)
+		ns->lba_shift = 9;
+	ns->noiob = le16_to_cpu(id->noiob);
+	ns->ms = le16_to_cpu(id->lbaf[id->flbas & NVME_NS_FLBAS_LBA_MASK].ms);
+	ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
+	/* the PI implementation requires metadata equal t10 pi tuple size */
+	if (ns->ms == sizeof(struct t10_pi_tuple))
+		ns->pi_type = id->dps & NVME_NS_DPS_PI_MASK;
+	else
+		ns->pi_type = 0;
+
+	if (ns->noiob)
+		nvme_set_chunk_size(ns);
+	nvme_update_disk_info(disk, ns, id);
+	if (ns->ndev)
+		nvme_nvm_update_nvm_info(ns);
+#ifdef CONFIG_NVME_MULTIPATH
+	if (ns->head->disk) {
+		nvme_update_disk_info(ns->head->disk, ns, id);
+		blk_queue_stack_limits(ns->head->disk->queue, ns->queue);
+		nvme_mpath_update_disk_size(ns->head->disk);
+	}
+#endif
+}
+
+static int nvme_revalidate_disk(struct gendisk *disk)
+{
+	struct nvme_ns *ns = disk->private_data;
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct nvme_id_ns *id;
+	struct nvme_ns_ids ids;
+	int ret = 0;
+
+	if (test_bit(NVME_NS_DEAD, &ns->flags)) {
+		set_capacity(disk, 0);
+		return -ENODEV;
+	}
+
+	id = nvme_identify_ns(ctrl, ns->head->ns_id);
+	if (!id)
+		return -ENODEV;
+
+	if (id->ncap == 0) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	__nvme_revalidate_disk(disk, id);
+	nvme_report_ns_ids(ctrl, ns->head->ns_id, id, &ids);
+	if (!nvme_ns_ids_equal(&ns->head->ids, &ids)) {
+		dev_err(ctrl->device,
+			"identifiers changed for nsid %d\n", ns->head->ns_id);
+		ret = -ENODEV;
+	}
+
+out:
+	kfree(id);
+	return ret;
+}
+
+static char nvme_pr_type(enum pr_type type)
+{
+	switch (type) {
+	case PR_WRITE_EXCLUSIVE:
+		return 1;
+	case PR_EXCLUSIVE_ACCESS:
+		return 2;
+	case PR_WRITE_EXCLUSIVE_REG_ONLY:
+		return 3;
+	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
+		return 4;
+	case PR_WRITE_EXCLUSIVE_ALL_REGS:
+		return 5;
+	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
+		return 6;
+	default:
+		return 0;
+	}
+};
+
+static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
+				u64 key, u64 sa_key, u8 op)
+{
+	struct nvme_ns_head *head = NULL;
+	struct nvme_ns *ns;
+	struct nvme_command c;
+	int srcu_idx, ret;
+	u8 data[16] = { 0, };
+
+	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
+	if (unlikely(!ns))
+		return -EWOULDBLOCK;
+
+	put_unaligned_le64(key, &data[0]);
+	put_unaligned_le64(sa_key, &data[8]);
+
+	memset(&c, 0, sizeof(c));
+	c.common.opcode = op;
+	c.common.nsid = cpu_to_le32(ns->head->ns_id);
+	c.common.cdw10[0] = cpu_to_le32(cdw10);
+
+	ret = nvme_submit_sync_cmd(ns->queue, &c, data, 16);
+	nvme_put_ns_from_disk(head, srcu_idx);
+	return ret;
+}
+
+static int nvme_pr_register(struct block_device *bdev, u64 old,
+		u64 new, unsigned flags)
+{
+	u32 cdw10;
+
+	if (flags & ~PR_FL_IGNORE_KEY)
+		return -EOPNOTSUPP;
+
+	cdw10 = old ? 2 : 0;
+	cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
+	cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
+	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
+}
+
+static int nvme_pr_reserve(struct block_device *bdev, u64 key,
+		enum pr_type type, unsigned flags)
+{
+	u32 cdw10;
+
+	if (flags & ~PR_FL_IGNORE_KEY)
+		return -EOPNOTSUPP;
+
+	cdw10 = nvme_pr_type(type) << 8;
+	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
+	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
+}
+
+static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
+		enum pr_type type, bool abort)
+{
+	u32 cdw10 = nvme_pr_type(type) << 8 | (abort ? 2 : 1);
+	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
+}
+
+static int nvme_pr_clear(struct block_device *bdev, u64 key)
+{
+	u32 cdw10 = 1 | (key ? 1 << 3 : 0);
+	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
+}
+
+static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
+{
+	u32 cdw10 = nvme_pr_type(type) << 8 | (key ? 1 << 3 : 0);
+	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
+}
+
+static const struct pr_ops nvme_pr_ops = {
+	.pr_register	= nvme_pr_register,
+	.pr_reserve	= nvme_pr_reserve,
+	.pr_release	= nvme_pr_release,
+	.pr_preempt	= nvme_pr_preempt,
+	.pr_clear	= nvme_pr_clear,
+};
+
+#ifdef CONFIG_BLK_SED_OPAL
+int nvme_sec_submit(void *data, u16 spsp, u8 secp, void *buffer, size_t len,
+		bool send)
+{
+	struct nvme_ctrl *ctrl = data;
+	struct nvme_command cmd;
+
+	memset(&cmd, 0, sizeof(cmd));
+	if (send)
+		cmd.common.opcode = nvme_admin_security_send;
+	else
+		cmd.common.opcode = nvme_admin_security_recv;
+	cmd.common.nsid = 0;
+	cmd.common.cdw10[0] = cpu_to_le32(((u32)secp) << 24 | ((u32)spsp) << 8);
+	cmd.common.cdw10[1] = cpu_to_le32(len);
+
+	return __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, buffer, len,
+				      ADMIN_TIMEOUT, NVME_QID_ANY, 1, 0);
+}
+EXPORT_SYMBOL_GPL(nvme_sec_submit);
+#endif /* CONFIG_BLK_SED_OPAL */
+
+static const struct block_device_operations nvme_fops = {
+	.owner		= THIS_MODULE,
+	.ioctl		= nvme_ioctl,
+	.compat_ioctl	= nvme_ioctl,
+	.open		= nvme_open,
+	.release	= nvme_release,
+	.getgeo		= nvme_getgeo,
+	.revalidate_disk= nvme_revalidate_disk,
+	.pr_ops		= &nvme_pr_ops,
+};
+
+#ifdef CONFIG_NVME_MULTIPATH
+static int nvme_ns_head_open(struct block_device *bdev, fmode_t mode)
+{
+	struct nvme_ns_head *head = bdev->bd_disk->private_data;
+
+	if (!kref_get_unless_zero(&head->ref))
+		return -ENXIO;
+	return 0;
+}
+
+static void nvme_ns_head_release(struct gendisk *disk, fmode_t mode)
+{
+	nvme_put_ns_head(disk->private_data);
+}
+
+const struct block_device_operations nvme_ns_head_ops = {
+	.owner		= THIS_MODULE,
+	.open		= nvme_ns_head_open,
+	.release	= nvme_ns_head_release,
+	.ioctl		= nvme_ioctl,
+	.compat_ioctl	= nvme_ioctl,
+	.getgeo		= nvme_getgeo,
+	.pr_ops		= &nvme_pr_ops,
+};
+#endif /* CONFIG_NVME_MULTIPATH */
+
+static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
+{
+	unsigned long timeout =
+		((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
+	u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
+	int ret;
+
+	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
+		if (csts == ~0)
+			return -ENODEV;
+		if ((csts & NVME_CSTS_RDY) == bit)
+			break;
+
+		msleep(100);
+		if (fatal_signal_pending(current))
+			return -EINTR;
+		if (time_after(jiffies, timeout)) {
+			dev_err(ctrl->device,
+				"Device not ready; aborting %s\n", enabled ?
+						"initialisation" : "reset");
+			return -ENODEV;
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * If the device has been passed off to us in an enabled state, just clear
+ * the enabled bit.  The spec says we should set the 'shutdown notification
+ * bits', but doing so may cause the device to complete commands to the
+ * admin queue ... and we don't know what memory that might be pointing at!
+ */
+int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
+{
+	int ret;
+
+	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
+	ctrl->ctrl_config &= ~NVME_CC_ENABLE;
+
+	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+	if (ret)
+		return ret;
+
+	if (ctrl->quirks & NVME_QUIRK_DELAY_BEFORE_CHK_RDY)
+		msleep(NVME_QUIRK_DELAY_AMOUNT);
+
+	return nvme_wait_ready(ctrl, cap, false);
+}
+EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
+
+int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
+{
+	/*
+	 * Default to a 4K page size, with the intention to update this
+	 * path in the future to accomodate architectures with differing
+	 * kernel and IO page sizes.
+	 */
+	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
+	int ret;
+
+	if (page_shift < dev_page_min) {
+		dev_err(ctrl->device,
+			"Minimum device page size %u too large for host (%u)\n",
+			1 << dev_page_min, 1 << page_shift);
+		return -ENODEV;
+	}
+
+	ctrl->page_size = 1 << page_shift;
+
+	ctrl->ctrl_config = NVME_CC_CSS_NVM;
+	ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
+	ctrl->ctrl_config |= NVME_CC_AMS_RR | NVME_CC_SHN_NONE;
+	ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
+	ctrl->ctrl_config |= NVME_CC_ENABLE;
+
+	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+	if (ret)
+		return ret;
+	return nvme_wait_ready(ctrl, cap, true);
+}
+EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
+
+int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
+{
+	unsigned long timeout = jiffies + (ctrl->shutdown_timeout * HZ);
+	u32 csts;
+	int ret;
+
+	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
+	ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
+
+	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+	if (ret)
+		return ret;
+
+	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
+		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
+			break;
+
+		msleep(100);
+		if (fatal_signal_pending(current))
+			return -EINTR;
+		if (time_after(jiffies, timeout)) {
+			dev_err(ctrl->device,
+				"Device shutdown incomplete; abort shutdown\n");
+			return -ENODEV;
+		}
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);
+
+static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
+		struct request_queue *q)
+{
+	bool vwc = false;
+
+	if (ctrl->max_hw_sectors) {
+		u32 max_segments =
+			(ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
+
+		max_segments = min_not_zero(max_segments, ctrl->max_segments);
+		blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
+		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
+	}
+	if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) &&
+	    is_power_of_2(ctrl->max_hw_sectors))
+		blk_queue_chunk_sectors(q, ctrl->max_hw_sectors);
+	blk_queue_virt_boundary(q, ctrl->page_size - 1);
+	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
+		vwc = true;
+	blk_queue_write_cache(q, vwc, vwc);
+}
+
+static int nvme_configure_timestamp(struct nvme_ctrl *ctrl)
+{
+	__le64 ts;
+	int ret;
+
+	if (!(ctrl->oncs & NVME_CTRL_ONCS_TIMESTAMP))
+		return 0;
+
+	ts = cpu_to_le64(ktime_to_ms(ktime_get_real()));
+	ret = nvme_set_features(ctrl, NVME_FEAT_TIMESTAMP, 0, &ts, sizeof(ts),
+			NULL);
+	if (ret)
+		dev_warn_once(ctrl->device,
+			"could not set timestamp (%d)\n", ret);
+	return ret;
+}
+
+static int nvme_configure_apst(struct nvme_ctrl *ctrl)
+{
+	/*
+	 * APST (Autonomous Power State Transition) lets us program a
+	 * table of power state transitions that the controller will
+	 * perform automatically.  We configure it with a simple
+	 * heuristic: we are willing to spend at most 2% of the time
+	 * transitioning between power states.  Therefore, when running
+	 * in any given state, we will enter the next lower-power
+	 * non-operational state after waiting 50 * (enlat + exlat)
+	 * microseconds, as long as that state's exit latency is under
+	 * the requested maximum latency.
+	 *
+	 * We will not autonomously enter any non-operational state for
+	 * which the total latency exceeds ps_max_latency_us.  Users
+	 * can set ps_max_latency_us to zero to turn off APST.
+	 */
+
+	unsigned apste;
+	struct nvme_feat_auto_pst *table;
+	u64 max_lat_us = 0;
+	int max_ps = -1;
+	int ret;
+
+	/*
+	 * If APST isn't supported or if we haven't been initialized yet,
+	 * then don't do anything.
+	 */
+	if (!ctrl->apsta)
+		return 0;
+
+	if (ctrl->npss > 31) {
+		dev_warn(ctrl->device, "NPSS is invalid; not using APST\n");
+		return 0;
+	}
+
+	table = kzalloc(sizeof(*table), GFP_KERNEL);
+	if (!table)
+		return 0;
+
+	if (!ctrl->apst_enabled || ctrl->ps_max_latency_us == 0) {
+		/* Turn off APST. */
+		apste = 0;
+		dev_dbg(ctrl->device, "APST disabled\n");
+	} else {
+		__le64 target = cpu_to_le64(0);
+		int state;
+
+		/*
+		 * Walk through all states from lowest- to highest-power.
+		 * According to the spec, lower-numbered states use more
+		 * power.  NPSS, despite the name, is the index of the
+		 * lowest-power state, not the number of states.
+		 */
+		for (state = (int)ctrl->npss; state >= 0; state--) {
+			u64 total_latency_us, exit_latency_us, transition_ms;
+
+			if (target)
+				table->entries[state] = target;
+
+			/*
+			 * Don't allow transitions to the deepest state
+			 * if it's quirked off.
+			 */
+			if (state == ctrl->npss &&
+			    (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS))
+				continue;
+
+			/*
+			 * Is this state a useful non-operational state for
+			 * higher-power states to autonomously transition to?
+			 */
+			if (!(ctrl->psd[state].flags &
+			      NVME_PS_FLAGS_NON_OP_STATE))
+				continue;
+
+			exit_latency_us =
+				(u64)le32_to_cpu(ctrl->psd[state].exit_lat);
+			if (exit_latency_us > ctrl->ps_max_latency_us)
+				continue;
+
+			total_latency_us =
+				exit_latency_us +
+				le32_to_cpu(ctrl->psd[state].entry_lat);
+
+			/*
+			 * This state is good.  Use it as the APST idle
+			 * target for higher power states.
+			 */
+			transition_ms = total_latency_us + 19;
+			do_div(transition_ms, 20);
+			if (transition_ms > (1 << 24) - 1)
+				transition_ms = (1 << 24) - 1;
+
+			target = cpu_to_le64((state << 3) |
+					     (transition_ms << 8));
+
+			if (max_ps == -1)
+				max_ps = state;
+
+			if (total_latency_us > max_lat_us)
+				max_lat_us = total_latency_us;
+		}
+
+		apste = 1;
+
+		if (max_ps == -1) {
+			dev_dbg(ctrl->device, "APST enabled but no non-operational states are available\n");
+		} else {
+			dev_dbg(ctrl->device, "APST enabled: max PS = %d, max round-trip latency = %lluus, table = %*phN\n",
+				max_ps, max_lat_us, (int)sizeof(*table), table);
+		}
+	}
+
+	ret = nvme_set_features(ctrl, NVME_FEAT_AUTO_PST, apste,
+				table, sizeof(*table), NULL);
+	if (ret)
+		dev_err(ctrl->device, "failed to set APST feature (%d)\n", ret);
+
+	kfree(table);
+	return ret;
+}
+
+static void nvme_set_latency_tolerance(struct device *dev, s32 val)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+	u64 latency;
+
+	switch (val) {
+	case PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT:
+	case PM_QOS_LATENCY_ANY:
+		latency = U64_MAX;
+		break;
+
+	default:
+		latency = val;
+	}
+
+	if (ctrl->ps_max_latency_us != latency) {
+		ctrl->ps_max_latency_us = latency;
+		if (ctrl->state == NVME_CTRL_LIVE)
+			nvme_configure_apst(ctrl);
+	}
+}
+
+struct nvme_core_quirk_entry {
+	/*
+	 * NVMe model and firmware strings are padded with spaces.  For
+	 * simplicity, strings in the quirk table are padded with NULLs
+	 * instead.
+	 */
+	u16 vid;
+	const char *mn;
+	const char *fr;
+	unsigned long quirks;
+};
+
+static const struct nvme_core_quirk_entry core_quirks[] = {
+	{
+		/*
+		 * This Toshiba device seems to die using any APST states.  See:
+		 * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1678184/comments/11
+		 */
+		.vid = 0x1179,
+		.mn = "THNSF5256GPUK TOSHIBA",
+		.quirks = NVME_QUIRK_NO_APST,
+	}
+};
+
+/* match is null-terminated but idstr is space-padded. */
+static bool string_matches(const char *idstr, const char *match, size_t len)
+{
+	size_t matchlen;
+
+	if (!match)
+		return true;
+
+	matchlen = strlen(match);
+	WARN_ON_ONCE(matchlen > len);
+
+	if (memcmp(idstr, match, matchlen))
+		return false;
+
+	for (; matchlen < len; matchlen++)
+		if (idstr[matchlen] != ' ')
+			return false;
+
+	return true;
+}
+
+static bool quirk_matches(const struct nvme_id_ctrl *id,
+			  const struct nvme_core_quirk_entry *q)
+{
+	return q->vid == le16_to_cpu(id->vid) &&
+		string_matches(id->mn, q->mn, sizeof(id->mn)) &&
+		string_matches(id->fr, q->fr, sizeof(id->fr));
+}
+
+static void nvme_init_subnqn(struct nvme_subsystem *subsys, struct nvme_ctrl *ctrl,
+		struct nvme_id_ctrl *id)
+{
+	size_t nqnlen;
+	int off;
+
+	nqnlen = strnlen(id->subnqn, NVMF_NQN_SIZE);
+	if (nqnlen > 0 && nqnlen < NVMF_NQN_SIZE) {
+		strncpy(subsys->subnqn, id->subnqn, NVMF_NQN_SIZE);
+		return;
+	}
+
+	if (ctrl->vs >= NVME_VS(1, 2, 1))
+		dev_warn(ctrl->device, "missing or invalid SUBNQN field.\n");
+
+	/* Generate a "fake" NQN per Figure 254 in NVMe 1.3 + ECN 001 */
+	off = snprintf(subsys->subnqn, NVMF_NQN_SIZE,
+			"nqn.2014.08.org.nvmexpress:%04x%04x",
+			le16_to_cpu(id->vid), le16_to_cpu(id->ssvid));
+	memcpy(subsys->subnqn + off, id->sn, sizeof(id->sn));
+	off += sizeof(id->sn);
+	memcpy(subsys->subnqn + off, id->mn, sizeof(id->mn));
+	off += sizeof(id->mn);
+	memset(subsys->subnqn + off, 0, sizeof(subsys->subnqn) - off);
+}
+
+static void __nvme_release_subsystem(struct nvme_subsystem *subsys)
+{
+	ida_simple_remove(&nvme_subsystems_ida, subsys->instance);
+	kfree(subsys);
+}
+
+static void nvme_release_subsystem(struct device *dev)
+{
+	__nvme_release_subsystem(container_of(dev, struct nvme_subsystem, dev));
+}
+
+static void nvme_destroy_subsystem(struct kref *ref)
+{
+	struct nvme_subsystem *subsys =
+			container_of(ref, struct nvme_subsystem, ref);
+
+	mutex_lock(&nvme_subsystems_lock);
+	list_del(&subsys->entry);
+	mutex_unlock(&nvme_subsystems_lock);
+
+	ida_destroy(&subsys->ns_ida);
+	device_del(&subsys->dev);
+	put_device(&subsys->dev);
+}
+
+static void nvme_put_subsystem(struct nvme_subsystem *subsys)
+{
+	kref_put(&subsys->ref, nvme_destroy_subsystem);
+}
+
+static struct nvme_subsystem *__nvme_find_get_subsystem(const char *subsysnqn)
+{
+	struct nvme_subsystem *subsys;
+
+	lockdep_assert_held(&nvme_subsystems_lock);
+
+	/*
+	 * Fail matches for discovery subsystems. This results
+	 * in each discovery controller bound to a unique subsystem.
+	 * This avoids issues with validating controller values
+	 * that can only be true when there is a single unique subsystem.
+	 * There may be multiple and completely independent entities
+	 * that provide discovery controllers.
+	 */
+	if (!strcmp(subsysnqn, NVME_DISC_SUBSYS_NAME))
+		return NULL;
+
+	list_for_each_entry(subsys, &nvme_subsystems, entry) {
+		if (strcmp(subsys->subnqn, subsysnqn))
+			continue;
+		if (!kref_get_unless_zero(&subsys->ref))
+			continue;
+		return subsys;
+	}
+
+	return NULL;
+}
+
+#define SUBSYS_ATTR_RO(_name, _mode, _show)			\
+	struct device_attribute subsys_attr_##_name = \
+		__ATTR(_name, _mode, _show, NULL)
+
+static ssize_t nvme_subsys_show_nqn(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct nvme_subsystem *subsys =
+		container_of(dev, struct nvme_subsystem, dev);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", subsys->subnqn);
+}
+static SUBSYS_ATTR_RO(subsysnqn, S_IRUGO, nvme_subsys_show_nqn);
+
+#define nvme_subsys_show_str_function(field)				\
+static ssize_t subsys_##field##_show(struct device *dev,		\
+			    struct device_attribute *attr, char *buf)	\
+{									\
+	struct nvme_subsystem *subsys =					\
+		container_of(dev, struct nvme_subsystem, dev);		\
+	return sprintf(buf, "%.*s\n",					\
+		       (int)sizeof(subsys->field), subsys->field);	\
+}									\
+static SUBSYS_ATTR_RO(field, S_IRUGO, subsys_##field##_show);
+
+nvme_subsys_show_str_function(model);
+nvme_subsys_show_str_function(serial);
+nvme_subsys_show_str_function(firmware_rev);
+
+static struct attribute *nvme_subsys_attrs[] = {
+	&subsys_attr_model.attr,
+	&subsys_attr_serial.attr,
+	&subsys_attr_firmware_rev.attr,
+	&subsys_attr_subsysnqn.attr,
+	NULL,
+};
+
+static struct attribute_group nvme_subsys_attrs_group = {
+	.attrs = nvme_subsys_attrs,
+};
+
+static const struct attribute_group *nvme_subsys_attrs_groups[] = {
+	&nvme_subsys_attrs_group,
+	NULL,
+};
+
+static int nvme_active_ctrls(struct nvme_subsystem *subsys)
+{
+	int count = 0;
+	struct nvme_ctrl *ctrl;
+
+	mutex_lock(&subsys->lock);
+	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
+		if (ctrl->state != NVME_CTRL_DELETING &&
+		    ctrl->state != NVME_CTRL_DEAD)
+			count++;
+	}
+	mutex_unlock(&subsys->lock);
+
+	return count;
+}
+
+static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
+{
+	struct nvme_subsystem *subsys, *found;
+	int ret;
+
+	subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
+	if (!subsys)
+		return -ENOMEM;
+	ret = ida_simple_get(&nvme_subsystems_ida, 0, 0, GFP_KERNEL);
+	if (ret < 0) {
+		kfree(subsys);
+		return ret;
+	}
+	subsys->instance = ret;
+	mutex_init(&subsys->lock);
+	kref_init(&subsys->ref);
+	INIT_LIST_HEAD(&subsys->ctrls);
+	INIT_LIST_HEAD(&subsys->nsheads);
+	nvme_init_subnqn(subsys, ctrl, id);
+	memcpy(subsys->serial, id->sn, sizeof(subsys->serial));
+	memcpy(subsys->model, id->mn, sizeof(subsys->model));
+	memcpy(subsys->firmware_rev, id->fr, sizeof(subsys->firmware_rev));
+	subsys->vendor_id = le16_to_cpu(id->vid);
+	subsys->cmic = id->cmic;
+
+	subsys->dev.class = nvme_subsys_class;
+	subsys->dev.release = nvme_release_subsystem;
+	subsys->dev.groups = nvme_subsys_attrs_groups;
+	dev_set_name(&subsys->dev, "nvme-subsys%d", subsys->instance);
+	device_initialize(&subsys->dev);
+
+	mutex_lock(&nvme_subsystems_lock);
+	found = __nvme_find_get_subsystem(subsys->subnqn);
+	if (found) {
+		/*
+		 * Verify that the subsystem actually supports multiple
+		 * controllers, else bail out.
+		 */
+		if (!(ctrl->opts && ctrl->opts->discovery_nqn) &&
+		    nvme_active_ctrls(found) && !(id->cmic & (1 << 1))) {
+			dev_err(ctrl->device,
+				"ignoring ctrl due to duplicate subnqn (%s).\n",
+				found->subnqn);
+			nvme_put_subsystem(found);
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		__nvme_release_subsystem(subsys);
+		subsys = found;
+	} else {
+		ret = device_add(&subsys->dev);
+		if (ret) {
+			dev_err(ctrl->device,
+				"failed to register subsystem device.\n");
+			goto out_unlock;
+		}
+		ida_init(&subsys->ns_ida);
+		list_add_tail(&subsys->entry, &nvme_subsystems);
+	}
+
+	ctrl->subsys = subsys;
+	mutex_unlock(&nvme_subsystems_lock);
+
+	if (sysfs_create_link(&subsys->dev.kobj, &ctrl->device->kobj,
+			dev_name(ctrl->device))) {
+		dev_err(ctrl->device,
+			"failed to create sysfs link from subsystem.\n");
+		/* the transport driver will eventually put the subsystem */
+		return -EINVAL;
+	}
+
+	mutex_lock(&subsys->lock);
+	list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
+	mutex_unlock(&subsys->lock);
+
+	return 0;
+
+out_unlock:
+	mutex_unlock(&nvme_subsystems_lock);
+	put_device(&subsys->dev);
+	return ret;
+}
+
+int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp,
+		void *log, size_t size, u64 offset)
+{
+	struct nvme_command c = { };
+	unsigned long dwlen = size / 4 - 1;
+
+	c.get_log_page.opcode = nvme_admin_get_log_page;
+	c.get_log_page.nsid = cpu_to_le32(nsid);
+	c.get_log_page.lid = log_page;
+	c.get_log_page.lsp = lsp;
+	c.get_log_page.numdl = cpu_to_le16(dwlen & ((1 << 16) - 1));
+	c.get_log_page.numdu = cpu_to_le16(dwlen >> 16);
+	c.get_log_page.lpol = cpu_to_le32(lower_32_bits(offset));
+	c.get_log_page.lpou = cpu_to_le32(upper_32_bits(offset));
+
+	return nvme_submit_sync_cmd(ctrl->admin_q, &c, log, size);
+}
+
+static int nvme_get_effects_log(struct nvme_ctrl *ctrl)
+{
+	int ret;
+
+	if (!ctrl->effects)
+		ctrl->effects = kzalloc(sizeof(*ctrl->effects), GFP_KERNEL);
+
+	if (!ctrl->effects)
+		return 0;
+
+	ret = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_CMD_EFFECTS, 0,
+			ctrl->effects, sizeof(*ctrl->effects), 0);
+	if (ret) {
+		kfree(ctrl->effects);
+		ctrl->effects = NULL;
+	}
+	return ret;
+}
+
+/*
+ * Initialize the cached copies of the Identify data and various controller
+ * register in our nvme_ctrl structure.  This should be called as soon as
+ * the admin queue is fully up and running.
+ */
+int nvme_init_identify(struct nvme_ctrl *ctrl)
+{
+	struct nvme_id_ctrl *id;
+	u64 cap;
+	int ret, page_shift;
+	u32 max_hw_sectors;
+	bool prev_apst_enabled;
+
+	ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
+	if (ret) {
+		dev_err(ctrl->device, "Reading VS failed (%d)\n", ret);
+		return ret;
+	}
+
+	ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
+	if (ret) {
+		dev_err(ctrl->device, "Reading CAP failed (%d)\n", ret);
+		return ret;
+	}
+	page_shift = NVME_CAP_MPSMIN(cap) + 12;
+
+	if (ctrl->vs >= NVME_VS(1, 1, 0))
+		ctrl->subsystem = NVME_CAP_NSSRC(cap);
+
+	ret = nvme_identify_ctrl(ctrl, &id);
+	if (ret) {
+		dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
+		return -EIO;
+	}
+
+	if (id->lpa & NVME_CTRL_LPA_CMD_EFFECTS_LOG) {
+		ret = nvme_get_effects_log(ctrl);
+		if (ret < 0)
+			goto out_free;
+	}
+
+	if (!ctrl->identified) {
+		int i;
+
+		ret = nvme_init_subsystem(ctrl, id);
+		if (ret)
+			goto out_free;
+
+		/*
+		 * Check for quirks.  Quirk can depend on firmware version,
+		 * so, in principle, the set of quirks present can change
+		 * across a reset.  As a possible future enhancement, we
+		 * could re-scan for quirks every time we reinitialize
+		 * the device, but we'd have to make sure that the driver
+		 * behaves intelligently if the quirks change.
+		 */
+		for (i = 0; i < ARRAY_SIZE(core_quirks); i++) {
+			if (quirk_matches(id, &core_quirks[i]))
+				ctrl->quirks |= core_quirks[i].quirks;
+		}
+	}
+
+	if (force_apst && (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS)) {
+		dev_warn(ctrl->device, "forcibly allowing all power states due to nvme_core.force_apst -- use at your own risk\n");
+		ctrl->quirks &= ~NVME_QUIRK_NO_DEEPEST_PS;
+	}
+
+	ctrl->oacs = le16_to_cpu(id->oacs);
+	ctrl->oncs = le16_to_cpup(&id->oncs);
+	ctrl->oaes = le32_to_cpu(id->oaes);
+	atomic_set(&ctrl->abort_limit, id->acl + 1);
+	ctrl->vwc = id->vwc;
+	ctrl->cntlid = le16_to_cpup(&id->cntlid);
+	if (id->mdts)
+		max_hw_sectors = 1 << (id->mdts + page_shift - 9);
+	else
+		max_hw_sectors = UINT_MAX;
+	ctrl->max_hw_sectors =
+		min_not_zero(ctrl->max_hw_sectors, max_hw_sectors);
+
+	nvme_set_queue_limits(ctrl, ctrl->admin_q);
+	ctrl->sgls = le32_to_cpu(id->sgls);
+	ctrl->kas = le16_to_cpu(id->kas);
+	ctrl->max_namespaces = le32_to_cpu(id->mnan);
+
+	if (id->rtd3e) {
+		/* us -> s */
+		u32 transition_time = le32_to_cpu(id->rtd3e) / 1000000;
+
+		ctrl->shutdown_timeout = clamp_t(unsigned int, transition_time,
+						 shutdown_timeout, 60);
+
+		if (ctrl->shutdown_timeout != shutdown_timeout)
+			dev_info(ctrl->device,
+				 "Shutdown timeout set to %u seconds\n",
+				 ctrl->shutdown_timeout);
+	} else
+		ctrl->shutdown_timeout = shutdown_timeout;
+
+	ctrl->npss = id->npss;
+	ctrl->apsta = id->apsta;
+	prev_apst_enabled = ctrl->apst_enabled;
+	if (ctrl->quirks & NVME_QUIRK_NO_APST) {
+		if (force_apst && id->apsta) {
+			dev_warn(ctrl->device, "forcibly allowing APST due to nvme_core.force_apst -- use at your own risk\n");
+			ctrl->apst_enabled = true;
+		} else {
+			ctrl->apst_enabled = false;
+		}
+	} else {
+		ctrl->apst_enabled = id->apsta;
+	}
+	memcpy(ctrl->psd, id->psd, sizeof(ctrl->psd));
+
+	if (ctrl->ops->flags & NVME_F_FABRICS) {
+		ctrl->icdoff = le16_to_cpu(id->icdoff);
+		ctrl->ioccsz = le32_to_cpu(id->ioccsz);
+		ctrl->iorcsz = le32_to_cpu(id->iorcsz);
+		ctrl->maxcmd = le16_to_cpu(id->maxcmd);
+
+		/*
+		 * In fabrics we need to verify the cntlid matches the
+		 * admin connect
+		 */
+		if (ctrl->cntlid != le16_to_cpu(id->cntlid)) {
+			ret = -EINVAL;
+			goto out_free;
+		}
+
+		if (!ctrl->opts->discovery_nqn && !ctrl->kas) {
+			dev_err(ctrl->device,
+				"keep-alive support is mandatory for fabrics\n");
+			ret = -EINVAL;
+			goto out_free;
+		}
+	} else {
+		ctrl->cntlid = le16_to_cpu(id->cntlid);
+		ctrl->hmpre = le32_to_cpu(id->hmpre);
+		ctrl->hmmin = le32_to_cpu(id->hmmin);
+		ctrl->hmminds = le32_to_cpu(id->hmminds);
+		ctrl->hmmaxd = le16_to_cpu(id->hmmaxd);
+	}
+
+	ret = nvme_mpath_init(ctrl, id);
+	kfree(id);
+
+	if (ret < 0)
+		return ret;
+
+	if (ctrl->apst_enabled && !prev_apst_enabled)
+		dev_pm_qos_expose_latency_tolerance(ctrl->device);
+	else if (!ctrl->apst_enabled && prev_apst_enabled)
+		dev_pm_qos_hide_latency_tolerance(ctrl->device);
+
+	ret = nvme_configure_apst(ctrl);
+	if (ret < 0)
+		return ret;
+	
+	ret = nvme_configure_timestamp(ctrl);
+	if (ret < 0)
+		return ret;
+
+	ret = nvme_configure_directives(ctrl);
+	if (ret < 0)
+		return ret;
+
+	ctrl->identified = true;
+
+	return 0;
+
+out_free:
+	kfree(id);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_init_identify);
+
+static int nvme_dev_open(struct inode *inode, struct file *file)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(inode->i_cdev, struct nvme_ctrl, cdev);
+
+	switch (ctrl->state) {
+	case NVME_CTRL_LIVE:
+	case NVME_CTRL_ADMIN_ONLY:
+		break;
+	default:
+		return -EWOULDBLOCK;
+	}
+
+	nvme_get_ctrl(ctrl);
+	if (!try_module_get(ctrl->ops->module)) {
+		nvme_put_ctrl(ctrl);
+		return -EINVAL;
+	}
+
+	file->private_data = ctrl;
+	return 0;
+}
+
+static int nvme_dev_release(struct inode *inode, struct file *file)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(inode->i_cdev, struct nvme_ctrl, cdev);
+
+	module_put(ctrl->ops->module);
+	nvme_put_ctrl(ctrl);
+	return 0;
+}
+
+static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
+{
+	struct nvme_ns *ns;
+	int ret;
+
+	down_read(&ctrl->namespaces_rwsem);
+	if (list_empty(&ctrl->namespaces)) {
+		ret = -ENOTTY;
+		goto out_unlock;
+	}
+
+	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
+	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
+		dev_warn(ctrl->device,
+			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	dev_warn(ctrl->device,
+		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
+	kref_get(&ns->kref);
+	up_read(&ctrl->namespaces_rwsem);
+
+	ret = nvme_user_cmd(ctrl, ns, argp);
+	nvme_put_ns(ns);
+	return ret;
+
+out_unlock:
+	up_read(&ctrl->namespaces_rwsem);
+	return ret;
+}
+
+static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
+		unsigned long arg)
+{
+	struct nvme_ctrl *ctrl = file->private_data;
+	void __user *argp = (void __user *)arg;
+
+	switch (cmd) {
+	case NVME_IOCTL_ADMIN_CMD:
+		return nvme_user_cmd(ctrl, NULL, argp);
+	case NVME_IOCTL_IO_CMD:
+		return nvme_dev_user_cmd(ctrl, argp);
+	case NVME_IOCTL_RESET:
+		dev_warn(ctrl->device, "resetting controller\n");
+		return nvme_reset_ctrl_sync(ctrl);
+	case NVME_IOCTL_SUBSYS_RESET:
+		return nvme_reset_subsystem(ctrl);
+	case NVME_IOCTL_RESCAN:
+		nvme_queue_scan(ctrl);
+		return 0;
+	default:
+		return -ENOTTY;
+	}
+}
+
+static const struct file_operations nvme_dev_fops = {
+	.owner		= THIS_MODULE,
+	.open		= nvme_dev_open,
+	.release	= nvme_dev_release,
+	.unlocked_ioctl	= nvme_dev_ioctl,
+	.compat_ioctl	= nvme_dev_ioctl,
+};
+
+static ssize_t nvme_sysfs_reset(struct device *dev,
+				struct device_attribute *attr, const char *buf,
+				size_t count)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+	int ret;
+
+	ret = nvme_reset_ctrl_sync(ctrl);
+	if (ret < 0)
+		return ret;
+	return count;
+}
+static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
+
+static ssize_t nvme_sysfs_rescan(struct device *dev,
+				struct device_attribute *attr, const char *buf,
+				size_t count)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	nvme_queue_scan(ctrl);
+	return count;
+}
+static DEVICE_ATTR(rescan_controller, S_IWUSR, NULL, nvme_sysfs_rescan);
+
+static inline struct nvme_ns_head *dev_to_ns_head(struct device *dev)
+{
+	struct gendisk *disk = dev_to_disk(dev);
+
+	if (disk->fops == &nvme_fops)
+		return nvme_get_ns_from_dev(dev)->head;
+	else
+		return disk->private_data;
+}
+
+static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	struct nvme_ns_head *head = dev_to_ns_head(dev);
+	struct nvme_ns_ids *ids = &head->ids;
+	struct nvme_subsystem *subsys = head->subsys;
+	int serial_len = sizeof(subsys->serial);
+	int model_len = sizeof(subsys->model);
+
+	if (!uuid_is_null(&ids->uuid))
+		return sprintf(buf, "uuid.%pU\n", &ids->uuid);
+
+	if (memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
+		return sprintf(buf, "eui.%16phN\n", ids->nguid);
+
+	if (memchr_inv(ids->eui64, 0, sizeof(ids->eui64)))
+		return sprintf(buf, "eui.%8phN\n", ids->eui64);
+
+	while (serial_len > 0 && (subsys->serial[serial_len - 1] == ' ' ||
+				  subsys->serial[serial_len - 1] == '\0'))
+		serial_len--;
+	while (model_len > 0 && (subsys->model[model_len - 1] == ' ' ||
+				 subsys->model[model_len - 1] == '\0'))
+		model_len--;
+
+	return sprintf(buf, "nvme.%04x-%*phN-%*phN-%08x\n", subsys->vendor_id,
+		serial_len, subsys->serial, model_len, subsys->model,
+		head->ns_id);
+}
+static DEVICE_ATTR_RO(wwid);
+
+static ssize_t nguid_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	return sprintf(buf, "%pU\n", dev_to_ns_head(dev)->ids.nguid);
+}
+static DEVICE_ATTR_RO(nguid);
+
+static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	struct nvme_ns_ids *ids = &dev_to_ns_head(dev)->ids;
+
+	/* For backward compatibility expose the NGUID to userspace if
+	 * we have no UUID set
+	 */
+	if (uuid_is_null(&ids->uuid)) {
+		printk_ratelimited(KERN_WARNING
+				   "No UUID available providing old NGUID\n");
+		return sprintf(buf, "%pU\n", ids->nguid);
+	}
+	return sprintf(buf, "%pU\n", &ids->uuid);
+}
+static DEVICE_ATTR_RO(uuid);
+
+static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	return sprintf(buf, "%8ph\n", dev_to_ns_head(dev)->ids.eui64);
+}
+static DEVICE_ATTR_RO(eui);
+
+static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	return sprintf(buf, "%d\n", dev_to_ns_head(dev)->ns_id);
+}
+static DEVICE_ATTR_RO(nsid);
+
+static struct attribute *nvme_ns_id_attrs[] = {
+	&dev_attr_wwid.attr,
+	&dev_attr_uuid.attr,
+	&dev_attr_nguid.attr,
+	&dev_attr_eui.attr,
+	&dev_attr_nsid.attr,
+#ifdef CONFIG_NVME_MULTIPATH
+	&dev_attr_ana_grpid.attr,
+	&dev_attr_ana_state.attr,
+#endif
+	NULL,
+};
+
+static umode_t nvme_ns_id_attrs_are_visible(struct kobject *kobj,
+		struct attribute *a, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct nvme_ns_ids *ids = &dev_to_ns_head(dev)->ids;
+
+	if (a == &dev_attr_uuid.attr) {
+		if (uuid_is_null(&ids->uuid) &&
+		    !memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
+			return 0;
+	}
+	if (a == &dev_attr_nguid.attr) {
+		if (!memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
+			return 0;
+	}
+	if (a == &dev_attr_eui.attr) {
+		if (!memchr_inv(ids->eui64, 0, sizeof(ids->eui64)))
+			return 0;
+	}
+#ifdef CONFIG_NVME_MULTIPATH
+	if (a == &dev_attr_ana_grpid.attr || a == &dev_attr_ana_state.attr) {
+		if (dev_to_disk(dev)->fops != &nvme_fops) /* per-path attr */
+			return 0;
+		if (!nvme_ctrl_use_ana(nvme_get_ns_from_dev(dev)->ctrl))
+			return 0;
+	}
+#endif
+	return a->mode;
+}
+
+const struct attribute_group nvme_ns_id_attr_group = {
+	.attrs		= nvme_ns_id_attrs,
+	.is_visible	= nvme_ns_id_attrs_are_visible,
+};
+
+const struct attribute_group *nvme_ns_id_attr_groups[] = {
+	&nvme_ns_id_attr_group,
+#ifdef CONFIG_NVM
+	&nvme_nvm_attr_group,
+#endif
+	NULL,
+};
+
+#define nvme_show_str_function(field)						\
+static ssize_t  field##_show(struct device *dev,				\
+			    struct device_attribute *attr, char *buf)		\
+{										\
+        struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
+        return sprintf(buf, "%.*s\n",						\
+		(int)sizeof(ctrl->subsys->field), ctrl->subsys->field);		\
+}										\
+static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
+
+nvme_show_str_function(model);
+nvme_show_str_function(serial);
+nvme_show_str_function(firmware_rev);
+
+#define nvme_show_int_function(field)						\
+static ssize_t  field##_show(struct device *dev,				\
+			    struct device_attribute *attr, char *buf)		\
+{										\
+        struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
+        return sprintf(buf, "%d\n", ctrl->field);	\
+}										\
+static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
+
+nvme_show_int_function(cntlid);
+
+static ssize_t nvme_sysfs_delete(struct device *dev,
+				struct device_attribute *attr, const char *buf,
+				size_t count)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	/* Can't delete non-created controllers */
+	if (!ctrl->created)
+		return -EBUSY;
+
+	if (device_remove_file_self(dev, attr))
+		nvme_delete_ctrl_sync(ctrl);
+	return count;
+}
+static DEVICE_ATTR(delete_controller, S_IWUSR, NULL, nvme_sysfs_delete);
+
+static ssize_t nvme_sysfs_show_transport(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->ops->name);
+}
+static DEVICE_ATTR(transport, S_IRUGO, nvme_sysfs_show_transport, NULL);
+
+static ssize_t nvme_sysfs_show_state(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+	static const char *const state_name[] = {
+		[NVME_CTRL_NEW]		= "new",
+		[NVME_CTRL_LIVE]	= "live",
+		[NVME_CTRL_ADMIN_ONLY]	= "only-admin",
+		[NVME_CTRL_RESETTING]	= "resetting",
+		[NVME_CTRL_CONNECTING]	= "connecting",
+		[NVME_CTRL_DELETING]	= "deleting",
+		[NVME_CTRL_DEAD]	= "dead",
+	};
+
+	if ((unsigned)ctrl->state < ARRAY_SIZE(state_name) &&
+	    state_name[ctrl->state])
+		return sprintf(buf, "%s\n", state_name[ctrl->state]);
+
+	return sprintf(buf, "unknown state\n");
+}
+
+static DEVICE_ATTR(state, S_IRUGO, nvme_sysfs_show_state, NULL);
+
+static ssize_t nvme_sysfs_show_subsysnqn(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->subsys->subnqn);
+}
+static DEVICE_ATTR(subsysnqn, S_IRUGO, nvme_sysfs_show_subsysnqn, NULL);
+
+static ssize_t nvme_sysfs_show_address(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	return ctrl->ops->get_address(ctrl, buf, PAGE_SIZE);
+}
+static DEVICE_ATTR(address, S_IRUGO, nvme_sysfs_show_address, NULL);
+
+static struct attribute *nvme_dev_attrs[] = {
+	&dev_attr_reset_controller.attr,
+	&dev_attr_rescan_controller.attr,
+	&dev_attr_model.attr,
+	&dev_attr_serial.attr,
+	&dev_attr_firmware_rev.attr,
+	&dev_attr_cntlid.attr,
+	&dev_attr_delete_controller.attr,
+	&dev_attr_transport.attr,
+	&dev_attr_subsysnqn.attr,
+	&dev_attr_address.attr,
+	&dev_attr_state.attr,
+	NULL
+};
+
+static umode_t nvme_dev_attrs_are_visible(struct kobject *kobj,
+		struct attribute *a, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	if (a == &dev_attr_delete_controller.attr && !ctrl->ops->delete_ctrl)
+		return 0;
+	if (a == &dev_attr_address.attr && !ctrl->ops->get_address)
+		return 0;
+
+	return a->mode;
+}
+
+static struct attribute_group nvme_dev_attrs_group = {
+	.attrs		= nvme_dev_attrs,
+	.is_visible	= nvme_dev_attrs_are_visible,
+};
+
+static const struct attribute_group *nvme_dev_attr_groups[] = {
+	&nvme_dev_attrs_group,
+	NULL,
+};
+
+static struct nvme_ns_head *__nvme_find_ns_head(struct nvme_subsystem *subsys,
+		unsigned nsid)
+{
+	struct nvme_ns_head *h;
+
+	lockdep_assert_held(&subsys->lock);
+
+	list_for_each_entry(h, &subsys->nsheads, entry) {
+		if (h->ns_id == nsid && kref_get_unless_zero(&h->ref))
+			return h;
+	}
+
+	return NULL;
+}
+
+static int __nvme_check_ids(struct nvme_subsystem *subsys,
+		struct nvme_ns_head *new)
+{
+	struct nvme_ns_head *h;
+
+	lockdep_assert_held(&subsys->lock);
+
+	list_for_each_entry(h, &subsys->nsheads, entry) {
+		if (nvme_ns_ids_valid(&new->ids) &&
+		    !list_empty(&h->list) &&
+		    nvme_ns_ids_equal(&new->ids, &h->ids))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
+		unsigned nsid, struct nvme_id_ns *id)
+{
+	struct nvme_ns_head *head;
+	int ret = -ENOMEM;
+
+	head = kzalloc(sizeof(*head), GFP_KERNEL);
+	if (!head)
+		goto out;
+	ret = ida_simple_get(&ctrl->subsys->ns_ida, 1, 0, GFP_KERNEL);
+	if (ret < 0)
+		goto out_free_head;
+	head->instance = ret;
+	INIT_LIST_HEAD(&head->list);
+	ret = init_srcu_struct(&head->srcu);
+	if (ret)
+		goto out_ida_remove;
+	head->subsys = ctrl->subsys;
+	head->ns_id = nsid;
+	kref_init(&head->ref);
+
+	nvme_report_ns_ids(ctrl, nsid, id, &head->ids);
+
+	ret = __nvme_check_ids(ctrl->subsys, head);
+	if (ret) {
+		dev_err(ctrl->device,
+			"duplicate IDs for nsid %d\n", nsid);
+		goto out_cleanup_srcu;
+	}
+
+	ret = nvme_mpath_alloc_disk(ctrl, head);
+	if (ret)
+		goto out_cleanup_srcu;
+
+	list_add_tail(&head->entry, &ctrl->subsys->nsheads);
+
+	kref_get(&ctrl->subsys->ref);
+
+	return head;
+out_cleanup_srcu:
+	cleanup_srcu_struct(&head->srcu);
+out_ida_remove:
+	ida_simple_remove(&ctrl->subsys->ns_ida, head->instance);
+out_free_head:
+	kfree(head);
+out:
+	return ERR_PTR(ret);
+}
+
+static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
+		struct nvme_id_ns *id)
+{
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	bool is_shared = id->nmic & (1 << 0);
+	struct nvme_ns_head *head = NULL;
+	int ret = 0;
+
+	mutex_lock(&ctrl->subsys->lock);
+	if (is_shared)
+		head = __nvme_find_ns_head(ctrl->subsys, nsid);
+	if (!head) {
+		head = nvme_alloc_ns_head(ctrl, nsid, id);
+		if (IS_ERR(head)) {
+			ret = PTR_ERR(head);
+			goto out_unlock;
+		}
+	} else {
+		struct nvme_ns_ids ids;
+
+		nvme_report_ns_ids(ctrl, nsid, id, &ids);
+		if (!nvme_ns_ids_equal(&head->ids, &ids)) {
+			dev_err(ctrl->device,
+				"IDs don't match for shared namespace %d\n",
+					nsid);
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+	}
+
+	list_add_tail(&ns->siblings, &head->list);
+	ns->head = head;
+
+out_unlock:
+	mutex_unlock(&ctrl->subsys->lock);
+	return ret;
+}
+
+static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
+{
+	struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
+	struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
+
+	return nsa->head->ns_id - nsb->head->ns_id;
+}
+
+static struct nvme_ns *nvme_find_get_ns(struct nvme_ctrl *ctrl, unsigned nsid)
+{
+	struct nvme_ns *ns, *ret = NULL;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list) {
+		if (ns->head->ns_id == nsid) {
+			if (!kref_get_unless_zero(&ns->kref))
+				continue;
+			ret = ns;
+			break;
+		}
+		if (ns->head->ns_id > nsid)
+			break;
+	}
+	up_read(&ctrl->namespaces_rwsem);
+	return ret;
+}
+
+static int nvme_setup_streams_ns(struct nvme_ctrl *ctrl, struct nvme_ns *ns)
+{
+	struct streams_directive_params s;
+	int ret;
+
+	if (!ctrl->nr_streams)
+		return 0;
+
+	ret = nvme_get_stream_params(ctrl, &s, ns->head->ns_id);
+	if (ret)
+		return ret;
+
+	ns->sws = le32_to_cpu(s.sws);
+	ns->sgs = le16_to_cpu(s.sgs);
+
+	if (ns->sws) {
+		unsigned int bs = 1 << ns->lba_shift;
+
+		blk_queue_io_min(ns->queue, bs * ns->sws);
+		if (ns->sgs)
+			blk_queue_io_opt(ns->queue, bs * ns->sws * ns->sgs);
+	}
+
+	return 0;
+}
+
+static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
+{
+	struct nvme_ns *ns;
+	struct gendisk *disk;
+	struct nvme_id_ns *id;
+	char disk_name[DISK_NAME_LEN];
+	int node = dev_to_node(ctrl->dev), flags = GENHD_FL_EXT_DEVT;
+
+	ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
+	if (!ns)
+		return;
+
+	ns->queue = blk_mq_init_queue(ctrl->tagset);
+	if (IS_ERR(ns->queue))
+		goto out_free_ns;
+	blk_queue_flag_set(QUEUE_FLAG_NONROT, ns->queue);
+	ns->queue->queuedata = ns;
+	ns->ctrl = ctrl;
+
+	kref_init(&ns->kref);
+	ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
+
+	blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
+	nvme_set_queue_limits(ctrl, ns->queue);
+
+	id = nvme_identify_ns(ctrl, nsid);
+	if (!id)
+		goto out_free_queue;
+
+	if (id->ncap == 0)
+		goto out_free_id;
+
+	if (nvme_init_ns_head(ns, nsid, id))
+		goto out_free_id;
+	nvme_setup_streams_ns(ctrl, ns);
+	nvme_set_disk_name(disk_name, ns, ctrl, &flags);
+
+	if ((ctrl->quirks & NVME_QUIRK_LIGHTNVM) && id->vs[0] == 0x1) {
+		if (nvme_nvm_register(ns, disk_name, node)) {
+			dev_warn(ctrl->device, "LightNVM init failure\n");
+			goto out_unlink_ns;
+		}
+	}
+
+	disk = alloc_disk_node(0, node);
+	if (!disk)
+		goto out_unlink_ns;
+
+	disk->fops = &nvme_fops;
+	disk->private_data = ns;
+	disk->queue = ns->queue;
+	disk->flags = flags;
+	memcpy(disk->disk_name, disk_name, DISK_NAME_LEN);
+	ns->disk = disk;
+
+	__nvme_revalidate_disk(disk, id);
+
+	down_write(&ctrl->namespaces_rwsem);
+	list_add_tail(&ns->list, &ctrl->namespaces);
+	up_write(&ctrl->namespaces_rwsem);
+
+	nvme_get_ctrl(ctrl);
+
+	device_add_disk(ctrl->device, ns->disk, nvme_ns_id_attr_groups);
+
+	nvme_mpath_add_disk(ns, id);
+	nvme_fault_inject_init(ns);
+	kfree(id);
+
+	return;
+ out_unlink_ns:
+	mutex_lock(&ctrl->subsys->lock);
+	list_del_rcu(&ns->siblings);
+	mutex_unlock(&ctrl->subsys->lock);
+ out_free_id:
+	kfree(id);
+ out_free_queue:
+	blk_cleanup_queue(ns->queue);
+ out_free_ns:
+	kfree(ns);
+}
+
+static void nvme_ns_remove(struct nvme_ns *ns)
+{
+	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
+		return;
+
+	nvme_fault_inject_fini(ns);
+
+	mutex_lock(&ns->ctrl->subsys->lock);
+	list_del_rcu(&ns->siblings);
+	mutex_unlock(&ns->ctrl->subsys->lock);
+	synchronize_rcu(); /* guarantee not available in head->list */
+	nvme_mpath_clear_current_path(ns);
+	synchronize_srcu(&ns->head->srcu); /* wait for concurrent submissions */
+
+	if (ns->disk && ns->disk->flags & GENHD_FL_UP) {
+		del_gendisk(ns->disk);
+		blk_cleanup_queue(ns->queue);
+		if (blk_get_integrity(ns->disk))
+			blk_integrity_unregister(ns->disk);
+	}
+
+	down_write(&ns->ctrl->namespaces_rwsem);
+	list_del_init(&ns->list);
+	up_write(&ns->ctrl->namespaces_rwsem);
+
+	nvme_mpath_check_last_path(ns);
+	nvme_put_ns(ns);
+}
+
+static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
+{
+	struct nvme_ns *ns;
+
+	ns = nvme_find_get_ns(ctrl, nsid);
+	if (ns) {
+		if (ns->disk && revalidate_disk(ns->disk))
+			nvme_ns_remove(ns);
+		nvme_put_ns(ns);
+	} else
+		nvme_alloc_ns(ctrl, nsid);
+}
+
+static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
+					unsigned nsid)
+{
+	struct nvme_ns *ns, *next;
+	LIST_HEAD(rm_list);
+
+	down_write(&ctrl->namespaces_rwsem);
+	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
+		if (ns->head->ns_id > nsid || test_bit(NVME_NS_DEAD, &ns->flags))
+			list_move_tail(&ns->list, &rm_list);
+	}
+	up_write(&ctrl->namespaces_rwsem);
+
+	list_for_each_entry_safe(ns, next, &rm_list, list)
+		nvme_ns_remove(ns);
+
+}
+
+static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
+{
+	struct nvme_ns *ns;
+	__le32 *ns_list;
+	unsigned i, j, nsid, prev = 0;
+	unsigned num_lists = DIV_ROUND_UP_ULL((u64)nn, 1024);
+	int ret = 0;
+
+	ns_list = kzalloc(NVME_IDENTIFY_DATA_SIZE, GFP_KERNEL);
+	if (!ns_list)
+		return -ENOMEM;
+
+	for (i = 0; i < num_lists; i++) {
+		ret = nvme_identify_ns_list(ctrl, prev, ns_list);
+		if (ret)
+			goto free;
+
+		for (j = 0; j < min(nn, 1024U); j++) {
+			nsid = le32_to_cpu(ns_list[j]);
+			if (!nsid)
+				goto out;
+
+			nvme_validate_ns(ctrl, nsid);
+
+			while (++prev < nsid) {
+				ns = nvme_find_get_ns(ctrl, prev);
+				if (ns) {
+					nvme_ns_remove(ns);
+					nvme_put_ns(ns);
+				}
+			}
+		}
+		nn -= j;
+	}
+ out:
+	nvme_remove_invalid_namespaces(ctrl, prev);
+ free:
+	kfree(ns_list);
+	return ret;
+}
+
+static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
+{
+	unsigned i;
+
+	for (i = 1; i <= nn; i++)
+		nvme_validate_ns(ctrl, i);
+
+	nvme_remove_invalid_namespaces(ctrl, nn);
+}
+
+static void nvme_clear_changed_ns_log(struct nvme_ctrl *ctrl)
+{
+	size_t log_size = NVME_MAX_CHANGED_NAMESPACES * sizeof(__le32);
+	__le32 *log;
+	int error;
+
+	log = kzalloc(log_size, GFP_KERNEL);
+	if (!log)
+		return;
+
+	/*
+	 * We need to read the log to clear the AEN, but we don't want to rely
+	 * on it for the changed namespace information as userspace could have
+	 * raced with us in reading the log page, which could cause us to miss
+	 * updates.
+	 */
+	error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_CHANGED_NS, 0, log,
+			log_size, 0);
+	if (error)
+		dev_warn(ctrl->device,
+			"reading changed ns log failed: %d\n", error);
+
+	kfree(log);
+}
+
+static void nvme_scan_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(work, struct nvme_ctrl, scan_work);
+	struct nvme_id_ctrl *id;
+	unsigned nn;
+
+	if (ctrl->state != NVME_CTRL_LIVE)
+		return;
+
+	WARN_ON_ONCE(!ctrl->tagset);
+
+	if (test_and_clear_bit(NVME_AER_NOTICE_NS_CHANGED, &ctrl->events)) {
+		dev_info(ctrl->device, "rescanning namespaces.\n");
+		nvme_clear_changed_ns_log(ctrl);
+	}
+
+	if (nvme_identify_ctrl(ctrl, &id))
+		return;
+
+	mutex_lock(&ctrl->scan_lock);
+	nn = le32_to_cpu(id->nn);
+	if (!nvme_ctrl_limited_cns(ctrl)) {
+		if (!nvme_scan_ns_list(ctrl, nn))
+			goto out_free_id;
+	}
+	nvme_scan_ns_sequential(ctrl, nn);
+out_free_id:
+	mutex_unlock(&ctrl->scan_lock);
+	kfree(id);
+	down_write(&ctrl->namespaces_rwsem);
+	list_sort(NULL, &ctrl->namespaces, ns_cmp);
+	up_write(&ctrl->namespaces_rwsem);
+}
+
+/*
+ * This function iterates the namespace list unlocked to allow recovery from
+ * controller failure. It is up to the caller to ensure the namespace list is
+ * not modified by scan work while this function is executing.
+ */
+void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns, *next;
+	LIST_HEAD(ns_list);
+
+	/* prevent racing with ns scanning */
+	flush_work(&ctrl->scan_work);
+
+	/*
+	 * The dead states indicates the controller was not gracefully
+	 * disconnected. In that case, we won't be able to flush any data while
+	 * removing the namespaces' disks; fail all the queues now to avoid
+	 * potentially having to clean up the failed sync later.
+	 */
+	if (ctrl->state == NVME_CTRL_DEAD)
+		nvme_kill_queues(ctrl);
+
+	down_write(&ctrl->namespaces_rwsem);
+	list_splice_init(&ctrl->namespaces, &ns_list);
+	up_write(&ctrl->namespaces_rwsem);
+
+	list_for_each_entry_safe(ns, next, &ns_list, list)
+		nvme_ns_remove(ns);
+}
+EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
+
+static void nvme_aen_uevent(struct nvme_ctrl *ctrl)
+{
+	char *envp[2] = { NULL, NULL };
+	u32 aen_result = ctrl->aen_result;
+
+	ctrl->aen_result = 0;
+	if (!aen_result)
+		return;
+
+	envp[0] = kasprintf(GFP_KERNEL, "NVME_AEN=%#08x", aen_result);
+	if (!envp[0])
+		return;
+	kobject_uevent_env(&ctrl->device->kobj, KOBJ_CHANGE, envp);
+	kfree(envp[0]);
+}
+
+static void nvme_async_event_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(work, struct nvme_ctrl, async_event_work);
+
+	nvme_aen_uevent(ctrl);
+
+	/*
+	 * The transport drivers must guarantee AER submission here is safe by
+	 * flushing ctrl async_event_work after changing the controller state
+	 * from LIVE and before freeing the admin queue.
+	*/
+	if (ctrl->state == NVME_CTRL_LIVE)
+		ctrl->ops->submit_async_event(ctrl);
+}
+
+static bool nvme_ctrl_pp_status(struct nvme_ctrl *ctrl)
+{
+
+	u32 csts;
+
+	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts))
+		return false;
+
+	if (csts == ~0)
+		return false;
+
+	return ((ctrl->ctrl_config & NVME_CC_ENABLE) && (csts & NVME_CSTS_PP));
+}
+
+static void nvme_get_fw_slot_info(struct nvme_ctrl *ctrl)
+{
+	struct nvme_fw_slot_info_log *log;
+
+	log = kmalloc(sizeof(*log), GFP_KERNEL);
+	if (!log)
+		return;
+
+	if (nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_FW_SLOT, 0, log,
+			sizeof(*log), 0))
+		dev_warn(ctrl->device, "Get FW SLOT INFO log error\n");
+	kfree(log);
+}
+
+static void nvme_fw_act_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl = container_of(work,
+				struct nvme_ctrl, fw_act_work);
+	unsigned long fw_act_timeout;
+
+	if (ctrl->mtfa)
+		fw_act_timeout = jiffies +
+				msecs_to_jiffies(ctrl->mtfa * 100);
+	else
+		fw_act_timeout = jiffies +
+				msecs_to_jiffies(admin_timeout * 1000);
+
+	nvme_stop_queues(ctrl);
+	while (nvme_ctrl_pp_status(ctrl)) {
+		if (time_after(jiffies, fw_act_timeout)) {
+			dev_warn(ctrl->device,
+				"Fw activation timeout, reset controller\n");
+			nvme_reset_ctrl(ctrl);
+			break;
+		}
+		msleep(100);
+	}
+
+	if (ctrl->state != NVME_CTRL_LIVE)
+		return;
+
+	nvme_start_queues(ctrl);
+	/* read FW slot information to clear the AER */
+	nvme_get_fw_slot_info(ctrl);
+}
+
+static void nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result)
+{
+	switch ((result & 0xff00) >> 8) {
+	case NVME_AER_NOTICE_NS_CHANGED:
+		set_bit(NVME_AER_NOTICE_NS_CHANGED, &ctrl->events);
+		nvme_queue_scan(ctrl);
+		break;
+	case NVME_AER_NOTICE_FW_ACT_STARTING:
+		queue_work(nvme_wq, &ctrl->fw_act_work);
+		break;
+#ifdef CONFIG_NVME_MULTIPATH
+	case NVME_AER_NOTICE_ANA:
+		if (!ctrl->ana_log_buf)
+			break;
+		queue_work(nvme_wq, &ctrl->ana_work);
+		break;
+#endif
+	default:
+		dev_warn(ctrl->device, "async event result %08x\n", result);
+	}
+}
+
+void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
+		volatile union nvme_result *res)
+{
+	u32 result = le32_to_cpu(res->u32);
+
+	if (le16_to_cpu(status) >> 1 != NVME_SC_SUCCESS)
+		return;
+
+	switch (result & 0x7) {
+	case NVME_AER_NOTICE:
+		nvme_handle_aen_notice(ctrl, result);
+		break;
+	case NVME_AER_ERROR:
+	case NVME_AER_SMART:
+	case NVME_AER_CSS:
+	case NVME_AER_VS:
+		ctrl->aen_result = result;
+		break;
+	default:
+		break;
+	}
+	queue_work(nvme_wq, &ctrl->async_event_work);
+}
+EXPORT_SYMBOL_GPL(nvme_complete_async_event);
+
+void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
+{
+	nvme_mpath_stop(ctrl);
+	nvme_stop_keep_alive(ctrl);
+	flush_work(&ctrl->async_event_work);
+	cancel_work_sync(&ctrl->fw_act_work);
+	if (ctrl->ops->stop_ctrl)
+		ctrl->ops->stop_ctrl(ctrl);
+}
+EXPORT_SYMBOL_GPL(nvme_stop_ctrl);
+
+void nvme_start_ctrl(struct nvme_ctrl *ctrl)
+{
+	if (ctrl->kato)
+		nvme_start_keep_alive(ctrl);
+
+	if (ctrl->queue_count > 1) {
+		nvme_queue_scan(ctrl);
+		nvme_enable_aen(ctrl);
+		queue_work(nvme_wq, &ctrl->async_event_work);
+		nvme_start_queues(ctrl);
+	}
+	ctrl->created = true;
+}
+EXPORT_SYMBOL_GPL(nvme_start_ctrl);
+
+void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
+{
+	dev_pm_qos_hide_latency_tolerance(ctrl->device);
+	cdev_device_del(&ctrl->cdev, ctrl->device);
+}
+EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
+
+static void nvme_free_ctrl(struct device *dev)
+{
+	struct nvme_ctrl *ctrl =
+		container_of(dev, struct nvme_ctrl, ctrl_device);
+	struct nvme_subsystem *subsys = ctrl->subsys;
+
+	ida_simple_remove(&nvme_instance_ida, ctrl->instance);
+	kfree(ctrl->effects);
+	nvme_mpath_uninit(ctrl);
+	__free_page(ctrl->discard_page);
+
+	if (subsys) {
+		mutex_lock(&subsys->lock);
+		list_del(&ctrl->subsys_entry);
+		mutex_unlock(&subsys->lock);
+		sysfs_remove_link(&subsys->dev.kobj, dev_name(ctrl->device));
+	}
+
+	ctrl->ops->free_ctrl(ctrl);
+
+	if (subsys)
+		nvme_put_subsystem(subsys);
+}
+
+/*
+ * Initialize a NVMe controller structures.  This needs to be called during
+ * earliest initialization so that we have the initialized structured around
+ * during probing.
+ */
+int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
+		const struct nvme_ctrl_ops *ops, unsigned long quirks)
+{
+	int ret;
+
+	ctrl->state = NVME_CTRL_NEW;
+	spin_lock_init(&ctrl->lock);
+	mutex_init(&ctrl->scan_lock);
+	INIT_LIST_HEAD(&ctrl->namespaces);
+	init_rwsem(&ctrl->namespaces_rwsem);
+	ctrl->dev = dev;
+	ctrl->ops = ops;
+	ctrl->quirks = quirks;
+	INIT_WORK(&ctrl->scan_work, nvme_scan_work);
+	INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
+	INIT_WORK(&ctrl->fw_act_work, nvme_fw_act_work);
+	INIT_WORK(&ctrl->delete_work, nvme_delete_ctrl_work);
+
+	INIT_DELAYED_WORK(&ctrl->ka_work, nvme_keep_alive_work);
+	memset(&ctrl->ka_cmd, 0, sizeof(ctrl->ka_cmd));
+	ctrl->ka_cmd.common.opcode = nvme_admin_keep_alive;
+
+	BUILD_BUG_ON(NVME_DSM_MAX_RANGES * sizeof(struct nvme_dsm_range) >
+			PAGE_SIZE);
+	ctrl->discard_page = alloc_page(GFP_KERNEL);
+	if (!ctrl->discard_page) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = ida_simple_get(&nvme_instance_ida, 0, 0, GFP_KERNEL);
+	if (ret < 0)
+		goto out;
+	ctrl->instance = ret;
+
+	device_initialize(&ctrl->ctrl_device);
+	ctrl->device = &ctrl->ctrl_device;
+	ctrl->device->devt = MKDEV(MAJOR(nvme_chr_devt), ctrl->instance);
+	ctrl->device->class = nvme_class;
+	ctrl->device->parent = ctrl->dev;
+	ctrl->device->groups = nvme_dev_attr_groups;
+	ctrl->device->release = nvme_free_ctrl;
+	dev_set_drvdata(ctrl->device, ctrl);
+	ret = dev_set_name(ctrl->device, "nvme%d", ctrl->instance);
+	if (ret)
+		goto out_release_instance;
+
+	cdev_init(&ctrl->cdev, &nvme_dev_fops);
+	ctrl->cdev.owner = ops->module;
+	ret = cdev_device_add(&ctrl->cdev, ctrl->device);
+	if (ret)
+		goto out_free_name;
+
+	/*
+	 * Initialize latency tolerance controls.  The sysfs files won't
+	 * be visible to userspace unless the device actually supports APST.
+	 */
+	ctrl->device->power.set_latency_tolerance = nvme_set_latency_tolerance;
+	dev_pm_qos_update_user_latency_tolerance(ctrl->device,
+		min(default_ps_max_latency_us, (unsigned long)S32_MAX));
+
+	return 0;
+out_free_name:
+	kfree_const(ctrl->device->kobj.name);
+out_release_instance:
+	ida_simple_remove(&nvme_instance_ida, ctrl->instance);
+out:
+	if (ctrl->discard_page)
+		__free_page(ctrl->discard_page);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_init_ctrl);
+
+/**
+ * nvme_kill_queues(): Ends all namespace queues
+ * @ctrl: the dead controller that needs to end
+ *
+ * Call this function when the driver determines it is unable to get the
+ * controller in a state capable of servicing IO.
+ */
+void nvme_kill_queues(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+
+	/* Forcibly unquiesce queues to avoid blocking dispatch */
+	if (ctrl->admin_q && !blk_queue_dying(ctrl->admin_q))
+		blk_mq_unquiesce_queue(ctrl->admin_q);
+
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		nvme_set_queue_dying(ns);
+
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_kill_queues);
+
+void nvme_unfreeze(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		blk_mq_unfreeze_queue(ns->queue);
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_unfreeze);
+
+void nvme_wait_freeze_timeout(struct nvme_ctrl *ctrl, long timeout)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list) {
+		timeout = blk_mq_freeze_queue_wait_timeout(ns->queue, timeout);
+		if (timeout <= 0)
+			break;
+	}
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_wait_freeze_timeout);
+
+void nvme_wait_freeze(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		blk_mq_freeze_queue_wait(ns->queue);
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_wait_freeze);
+
+void nvme_start_freeze(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		blk_freeze_queue_start(ns->queue);
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_start_freeze);
+
+void nvme_stop_queues(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		blk_mq_quiesce_queue(ns->queue);
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_stop_queues);
+
+void nvme_start_queues(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list)
+		blk_mq_unquiesce_queue(ns->queue);
+	up_read(&ctrl->namespaces_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvme_start_queues);
+
+int __init nvme_core_init(void)
+{
+	int result = -ENOMEM;
+
+	nvme_wq = alloc_workqueue("nvme-wq",
+			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
+	if (!nvme_wq)
+		goto out;
+
+	nvme_reset_wq = alloc_workqueue("nvme-reset-wq",
+			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
+	if (!nvme_reset_wq)
+		goto destroy_wq;
+
+	nvme_delete_wq = alloc_workqueue("nvme-delete-wq",
+			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
+	if (!nvme_delete_wq)
+		goto destroy_reset_wq;
+
+	result = alloc_chrdev_region(&nvme_chr_devt, 0, NVME_MINORS, "nvme");
+	if (result < 0)
+		goto destroy_delete_wq;
+
+	nvme_class = class_create(THIS_MODULE, "nvme");
+	if (IS_ERR(nvme_class)) {
+		result = PTR_ERR(nvme_class);
+		goto unregister_chrdev;
+	}
+
+	nvme_subsys_class = class_create(THIS_MODULE, "nvme-subsystem");
+	if (IS_ERR(nvme_subsys_class)) {
+		result = PTR_ERR(nvme_subsys_class);
+		goto destroy_class;
+	}
+	return 0;
+
+destroy_class:
+	class_destroy(nvme_class);
+unregister_chrdev:
+	unregister_chrdev_region(nvme_chr_devt, NVME_MINORS);
+destroy_delete_wq:
+	destroy_workqueue(nvme_delete_wq);
+destroy_reset_wq:
+	destroy_workqueue(nvme_reset_wq);
+destroy_wq:
+	destroy_workqueue(nvme_wq);
+out:
+	return result;
+}
+
+void nvme_core_exit(void)
+{
+	ida_destroy(&nvme_subsystems_ida);
+	class_destroy(nvme_subsys_class);
+	class_destroy(nvme_class);
+	unregister_chrdev_region(nvme_chr_devt, NVME_MINORS);
+	destroy_workqueue(nvme_delete_wq);
+	destroy_workqueue(nvme_reset_wq);
+	destroy_workqueue(nvme_wq);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0");
+module_init(nvme_core_init);
+module_exit(nvme_core_exit);
diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
new file mode 100644
index 000000000..3ae800e87
--- /dev/null
+++ b/drivers/nvme/host/fabrics.c
@@ -0,0 +1,1132 @@
+/*
+ * NVMe over Fabrics common host code.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/parser.h>
+#include <linux/seq_file.h>
+#include "nvme.h"
+#include "fabrics.h"
+
+static LIST_HEAD(nvmf_transports);
+static DECLARE_RWSEM(nvmf_transports_rwsem);
+
+static LIST_HEAD(nvmf_hosts);
+static DEFINE_MUTEX(nvmf_hosts_mutex);
+
+static struct nvmf_host *nvmf_default_host;
+
+static struct nvmf_host *__nvmf_host_find(const char *hostnqn)
+{
+	struct nvmf_host *host;
+
+	list_for_each_entry(host, &nvmf_hosts, list) {
+		if (!strcmp(host->nqn, hostnqn))
+			return host;
+	}
+
+	return NULL;
+}
+
+static struct nvmf_host *nvmf_host_add(const char *hostnqn)
+{
+	struct nvmf_host *host;
+
+	mutex_lock(&nvmf_hosts_mutex);
+	host = __nvmf_host_find(hostnqn);
+	if (host) {
+		kref_get(&host->ref);
+		goto out_unlock;
+	}
+
+	host = kmalloc(sizeof(*host), GFP_KERNEL);
+	if (!host)
+		goto out_unlock;
+
+	kref_init(&host->ref);
+	strlcpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
+
+	list_add_tail(&host->list, &nvmf_hosts);
+out_unlock:
+	mutex_unlock(&nvmf_hosts_mutex);
+	return host;
+}
+
+static struct nvmf_host *nvmf_host_default(void)
+{
+	struct nvmf_host *host;
+
+	host = kmalloc(sizeof(*host), GFP_KERNEL);
+	if (!host)
+		return NULL;
+
+	kref_init(&host->ref);
+	uuid_gen(&host->id);
+	snprintf(host->nqn, NVMF_NQN_SIZE,
+		"nqn.2014-08.org.nvmexpress:uuid:%pUb", &host->id);
+
+	mutex_lock(&nvmf_hosts_mutex);
+	list_add_tail(&host->list, &nvmf_hosts);
+	mutex_unlock(&nvmf_hosts_mutex);
+
+	return host;
+}
+
+static void nvmf_host_destroy(struct kref *ref)
+{
+	struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
+
+	mutex_lock(&nvmf_hosts_mutex);
+	list_del(&host->list);
+	mutex_unlock(&nvmf_hosts_mutex);
+
+	kfree(host);
+}
+
+static void nvmf_host_put(struct nvmf_host *host)
+{
+	if (host)
+		kref_put(&host->ref, nvmf_host_destroy);
+}
+
+/**
+ * nvmf_get_address() -  Get address/port
+ * @ctrl:	Host NVMe controller instance which we got the address
+ * @buf:	OUTPUT parameter that will contain the address/port
+ * @size:	buffer size
+ */
+int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
+{
+	int len = 0;
+
+	if (ctrl->opts->mask & NVMF_OPT_TRADDR)
+		len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
+	if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
+		len += snprintf(buf + len, size - len, "%strsvcid=%s",
+				(len) ? "," : "", ctrl->opts->trsvcid);
+	if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
+		len += snprintf(buf + len, size - len, "%shost_traddr=%s",
+				(len) ? "," : "", ctrl->opts->host_traddr);
+	len += snprintf(buf + len, size - len, "\n");
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(nvmf_get_address);
+
+/**
+ * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
+ * @ctrl:	Host NVMe controller instance maintaining the admin
+ *		queue used to submit the property read command to
+ *		the allocated NVMe controller resource on the target system.
+ * @off:	Starting offset value of the targeted property
+ *		register (see the fabrics section of the NVMe standard).
+ * @val:	OUTPUT parameter that will contain the value of
+ *		the property after a successful read.
+ *
+ * Used by the host system to retrieve a 32-bit capsule property value
+ * from an NVMe controller on the target system.
+ *
+ * ("Capsule property" is an "PCIe register concept" applied to the
+ * NVMe fabrics space.)
+ *
+ * Return:
+ *	0: successful read
+ *	> 0: NVMe error status code
+ *	< 0: Linux errno error code
+ */
+int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
+{
+	struct nvme_command cmd;
+	union nvme_result res;
+	int ret;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.prop_get.opcode = nvme_fabrics_command;
+	cmd.prop_get.fctype = nvme_fabrics_type_property_get;
+	cmd.prop_get.offset = cpu_to_le32(off);
+
+	ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
+			NVME_QID_ANY, 0, 0);
+
+	if (ret >= 0)
+		*val = le64_to_cpu(res.u64);
+	if (unlikely(ret != 0))
+		dev_err(ctrl->device,
+			"Property Get error: %d, offset %#x\n",
+			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmf_reg_read32);
+
+/**
+ * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
+ * @ctrl:	Host NVMe controller instance maintaining the admin
+ *		queue used to submit the property read command to
+ *		the allocated controller resource on the target system.
+ * @off:	Starting offset value of the targeted property
+ *		register (see the fabrics section of the NVMe standard).
+ * @val:	OUTPUT parameter that will contain the value of
+ *		the property after a successful read.
+ *
+ * Used by the host system to retrieve a 64-bit capsule property value
+ * from an NVMe controller on the target system.
+ *
+ * ("Capsule property" is an "PCIe register concept" applied to the
+ * NVMe fabrics space.)
+ *
+ * Return:
+ *	0: successful read
+ *	> 0: NVMe error status code
+ *	< 0: Linux errno error code
+ */
+int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
+{
+	struct nvme_command cmd;
+	union nvme_result res;
+	int ret;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.prop_get.opcode = nvme_fabrics_command;
+	cmd.prop_get.fctype = nvme_fabrics_type_property_get;
+	cmd.prop_get.attrib = 1;
+	cmd.prop_get.offset = cpu_to_le32(off);
+
+	ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
+			NVME_QID_ANY, 0, 0);
+
+	if (ret >= 0)
+		*val = le64_to_cpu(res.u64);
+	if (unlikely(ret != 0))
+		dev_err(ctrl->device,
+			"Property Get error: %d, offset %#x\n",
+			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmf_reg_read64);
+
+/**
+ * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
+ * @ctrl:	Host NVMe controller instance maintaining the admin
+ *		queue used to submit the property read command to
+ *		the allocated NVMe controller resource on the target system.
+ * @off:	Starting offset value of the targeted property
+ *		register (see the fabrics section of the NVMe standard).
+ * @val:	Input parameter that contains the value to be
+ *		written to the property.
+ *
+ * Used by the NVMe host system to write a 32-bit capsule property value
+ * to an NVMe controller on the target system.
+ *
+ * ("Capsule property" is an "PCIe register concept" applied to the
+ * NVMe fabrics space.)
+ *
+ * Return:
+ *	0: successful write
+ *	> 0: NVMe error status code
+ *	< 0: Linux errno error code
+ */
+int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
+{
+	struct nvme_command cmd;
+	int ret;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.prop_set.opcode = nvme_fabrics_command;
+	cmd.prop_set.fctype = nvme_fabrics_type_property_set;
+	cmd.prop_set.attrib = 0;
+	cmd.prop_set.offset = cpu_to_le32(off);
+	cmd.prop_set.value = cpu_to_le64(val);
+
+	ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
+			NVME_QID_ANY, 0, 0);
+	if (unlikely(ret))
+		dev_err(ctrl->device,
+			"Property Set error: %d, offset %#x\n",
+			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmf_reg_write32);
+
+/**
+ * nvmf_log_connect_error() - Error-parsing-diagnostic print
+ * out function for connect() errors.
+ *
+ * @ctrl: the specific /dev/nvmeX device that had the error.
+ *
+ * @errval: Error code to be decoded in a more human-friendly
+ *	    printout.
+ *
+ * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
+ *
+ * @cmd: This is the SQE portion of a submission capsule.
+ *
+ * @data: This is the "Data" portion of a submission capsule.
+ */
+static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
+		int errval, int offset, struct nvme_command *cmd,
+		struct nvmf_connect_data *data)
+{
+	int err_sctype = errval & (~NVME_SC_DNR);
+
+	switch (err_sctype) {
+
+	case (NVME_SC_CONNECT_INVALID_PARAM):
+		if (offset >> 16) {
+			char *inv_data = "Connect Invalid Data Parameter";
+
+			switch (offset & 0xffff) {
+			case (offsetof(struct nvmf_connect_data, cntlid)):
+				dev_err(ctrl->device,
+					"%s, cntlid: %d\n",
+					inv_data, data->cntlid);
+				break;
+			case (offsetof(struct nvmf_connect_data, hostnqn)):
+				dev_err(ctrl->device,
+					"%s, hostnqn \"%s\"\n",
+					inv_data, data->hostnqn);
+				break;
+			case (offsetof(struct nvmf_connect_data, subsysnqn)):
+				dev_err(ctrl->device,
+					"%s, subsysnqn \"%s\"\n",
+					inv_data, data->subsysnqn);
+				break;
+			default:
+				dev_err(ctrl->device,
+					"%s, starting byte offset: %d\n",
+				       inv_data, offset & 0xffff);
+				break;
+			}
+		} else {
+			char *inv_sqe = "Connect Invalid SQE Parameter";
+
+			switch (offset) {
+			case (offsetof(struct nvmf_connect_command, qid)):
+				dev_err(ctrl->device,
+				       "%s, qid %d\n",
+					inv_sqe, cmd->connect.qid);
+				break;
+			default:
+				dev_err(ctrl->device,
+					"%s, starting byte offset: %d\n",
+					inv_sqe, offset);
+			}
+		}
+		break;
+
+	case NVME_SC_CONNECT_INVALID_HOST:
+		dev_err(ctrl->device,
+			"Connect for subsystem %s is not allowed, hostnqn: %s\n",
+			data->subsysnqn, data->hostnqn);
+		break;
+
+	case NVME_SC_CONNECT_CTRL_BUSY:
+		dev_err(ctrl->device,
+			"Connect command failed: controller is busy or not available\n");
+		break;
+
+	case NVME_SC_CONNECT_FORMAT:
+		dev_err(ctrl->device,
+			"Connect incompatible format: %d",
+			cmd->connect.recfmt);
+		break;
+
+	case NVME_SC_HOST_PATH_ERROR:
+		dev_err(ctrl->device,
+			"Connect command failed: host path error\n");
+		break;
+
+	default:
+		dev_err(ctrl->device,
+			"Connect command failed, error wo/DNR bit: %d\n",
+			err_sctype);
+		break;
+	} /* switch (err_sctype) */
+}
+
+/**
+ * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
+ *				API function.
+ * @ctrl:	Host nvme controller instance used to request
+ *              a new NVMe controller allocation on the target
+ *              system and  establish an NVMe Admin connection to
+ *              that controller.
+ *
+ * This function enables an NVMe host device to request a new allocation of
+ * an NVMe controller resource on a target system as well establish a
+ * fabrics-protocol connection of the NVMe Admin queue between the
+ * host system device and the allocated NVMe controller on the
+ * target system via a NVMe Fabrics "Connect" command.
+ *
+ * Return:
+ *	0: success
+ *	> 0: NVMe error status code
+ *	< 0: Linux errno error code
+ *
+ */
+int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
+{
+	struct nvme_command cmd;
+	union nvme_result res;
+	struct nvmf_connect_data *data;
+	int ret;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.connect.opcode = nvme_fabrics_command;
+	cmd.connect.fctype = nvme_fabrics_type_connect;
+	cmd.connect.qid = 0;
+	cmd.connect.sqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
+
+	/*
+	 * Set keep-alive timeout in seconds granularity (ms * 1000)
+	 * and add a grace period for controller kato enforcement
+	 */
+	cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
+		cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	uuid_copy(&data->hostid, &ctrl->opts->host->id);
+	data->cntlid = cpu_to_le16(0xffff);
+	strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
+	strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
+
+	ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res,
+			data, sizeof(*data), 0, NVME_QID_ANY, 1,
+			BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
+	if (ret) {
+		nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
+				       &cmd, data);
+		goto out_free_data;
+	}
+
+	ctrl->cntlid = le16_to_cpu(res.u16);
+
+out_free_data:
+	kfree(data);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
+
+/**
+ * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
+ *			     API function.
+ * @ctrl:	Host nvme controller instance used to establish an
+ *		NVMe I/O queue connection to the already allocated NVMe
+ *		controller on the target system.
+ * @qid:	NVMe I/O queue number for the new I/O connection between
+ *		host and target (note qid == 0 is illegal as this is
+ *		the Admin queue, per NVMe standard).
+ *
+ * This function issues a fabrics-protocol connection
+ * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
+ * between the host system device and the allocated NVMe controller
+ * on the target system.
+ *
+ * Return:
+ *	0: success
+ *	> 0: NVMe error status code
+ *	< 0: Linux errno error code
+ */
+int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
+{
+	struct nvme_command cmd;
+	struct nvmf_connect_data *data;
+	union nvme_result res;
+	int ret;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.connect.opcode = nvme_fabrics_command;
+	cmd.connect.fctype = nvme_fabrics_type_connect;
+	cmd.connect.qid = cpu_to_le16(qid);
+	cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	uuid_copy(&data->hostid, &ctrl->opts->host->id);
+	data->cntlid = cpu_to_le16(ctrl->cntlid);
+	strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
+	strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
+
+	ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &res,
+			data, sizeof(*data), 0, qid, 1,
+			BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
+	if (ret) {
+		nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
+				       &cmd, data);
+	}
+	kfree(data);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
+
+bool nvmf_should_reconnect(struct nvme_ctrl *ctrl)
+{
+	if (ctrl->opts->max_reconnects == -1 ||
+	    ctrl->nr_reconnects < ctrl->opts->max_reconnects)
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(nvmf_should_reconnect);
+
+/**
+ * nvmf_register_transport() - NVMe Fabrics Library registration function.
+ * @ops:	Transport ops instance to be registered to the
+ *		common fabrics library.
+ *
+ * API function that registers the type of specific transport fabric
+ * being implemented to the common NVMe fabrics library. Part of
+ * the overall init sequence of starting up a fabrics driver.
+ */
+int nvmf_register_transport(struct nvmf_transport_ops *ops)
+{
+	if (!ops->create_ctrl)
+		return -EINVAL;
+
+	down_write(&nvmf_transports_rwsem);
+	list_add_tail(&ops->entry, &nvmf_transports);
+	up_write(&nvmf_transports_rwsem);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvmf_register_transport);
+
+/**
+ * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
+ * @ops:	Transport ops instance to be unregistered from the
+ *		common fabrics library.
+ *
+ * Fabrics API function that unregisters the type of specific transport
+ * fabric being implemented from the common NVMe fabrics library.
+ * Part of the overall exit sequence of unloading the implemented driver.
+ */
+void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
+{
+	down_write(&nvmf_transports_rwsem);
+	list_del(&ops->entry);
+	up_write(&nvmf_transports_rwsem);
+}
+EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
+
+static struct nvmf_transport_ops *nvmf_lookup_transport(
+		struct nvmf_ctrl_options *opts)
+{
+	struct nvmf_transport_ops *ops;
+
+	lockdep_assert_held(&nvmf_transports_rwsem);
+
+	list_for_each_entry(ops, &nvmf_transports, entry) {
+		if (strcmp(ops->name, opts->transport) == 0)
+			return ops;
+	}
+
+	return NULL;
+}
+
+/*
+ * For something we're not in a state to send to the device the default action
+ * is to busy it and retry it after the controller state is recovered.  However,
+ * if the controller is deleting or if anything is marked for failfast or
+ * nvme multipath it is immediately failed.
+ *
+ * Note: commands used to initialize the controller will be marked for failfast.
+ * Note: nvme cli/ioctl commands are marked for failfast.
+ */
+blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl,
+		struct request *rq)
+{
+	if (ctrl->state != NVME_CTRL_DELETING &&
+	    ctrl->state != NVME_CTRL_DEAD &&
+	    !blk_noretry_request(rq) && !(rq->cmd_flags & REQ_NVME_MPATH))
+		return BLK_STS_RESOURCE;
+
+	nvme_req(rq)->status = NVME_SC_HOST_PATH_ERROR;
+	blk_mq_start_request(rq);
+	nvme_complete_rq(rq);
+	return BLK_STS_OK;
+}
+EXPORT_SYMBOL_GPL(nvmf_fail_nonready_command);
+
+bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
+		bool queue_live)
+{
+	struct nvme_request *req = nvme_req(rq);
+
+	/*
+	 * If we are in some state of setup or teardown only allow
+	 * internally generated commands.
+	 */
+	if (!blk_rq_is_passthrough(rq) || (req->flags & NVME_REQ_USERCMD))
+		return false;
+
+	/*
+	 * Only allow commands on a live queue, except for the connect command,
+	 * which is require to set the queue live in the appropinquate states.
+	 */
+	switch (ctrl->state) {
+	case NVME_CTRL_CONNECTING:
+		if (req->cmd->common.opcode == nvme_fabrics_command &&
+		    req->cmd->fabrics.fctype == nvme_fabrics_type_connect)
+			return true;
+		break;
+	default:
+		break;
+	case NVME_CTRL_DEAD:
+		return false;
+	}
+
+	return queue_live;
+}
+EXPORT_SYMBOL_GPL(__nvmf_check_ready);
+
+static const match_table_t opt_tokens = {
+	{ NVMF_OPT_TRANSPORT,		"transport=%s"		},
+	{ NVMF_OPT_TRADDR,		"traddr=%s"		},
+	{ NVMF_OPT_TRSVCID,		"trsvcid=%s"		},
+	{ NVMF_OPT_NQN,			"nqn=%s"		},
+	{ NVMF_OPT_QUEUE_SIZE,		"queue_size=%d"		},
+	{ NVMF_OPT_NR_IO_QUEUES,	"nr_io_queues=%d"	},
+	{ NVMF_OPT_RECONNECT_DELAY,	"reconnect_delay=%d"	},
+	{ NVMF_OPT_CTRL_LOSS_TMO,	"ctrl_loss_tmo=%d"	},
+	{ NVMF_OPT_KATO,		"keep_alive_tmo=%d"	},
+	{ NVMF_OPT_HOSTNQN,		"hostnqn=%s"		},
+	{ NVMF_OPT_HOST_TRADDR,		"host_traddr=%s"	},
+	{ NVMF_OPT_HOST_ID,		"hostid=%s"		},
+	{ NVMF_OPT_DUP_CONNECT,		"duplicate_connect"	},
+	{ NVMF_OPT_ERR,			NULL			}
+};
+
+static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
+		const char *buf)
+{
+	substring_t args[MAX_OPT_ARGS];
+	char *options, *o, *p;
+	int token, ret = 0;
+	size_t nqnlen  = 0;
+	int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
+	uuid_t hostid;
+
+	/* Set defaults */
+	opts->queue_size = NVMF_DEF_QUEUE_SIZE;
+	opts->nr_io_queues = num_online_cpus();
+	opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
+	opts->kato = NVME_DEFAULT_KATO;
+	opts->duplicate_connect = false;
+
+	options = o = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	uuid_gen(&hostid);
+
+	while ((p = strsep(&o, ",\n")) != NULL) {
+		if (!*p)
+			continue;
+
+		token = match_token(p, opt_tokens, args);
+		opts->mask |= token;
+		switch (token) {
+		case NVMF_OPT_TRANSPORT:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			kfree(opts->transport);
+			opts->transport = p;
+			break;
+		case NVMF_OPT_NQN:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			kfree(opts->subsysnqn);
+			opts->subsysnqn = p;
+			nqnlen = strlen(opts->subsysnqn);
+			if (nqnlen >= NVMF_NQN_SIZE) {
+				pr_err("%s needs to be < %d bytes\n",
+					opts->subsysnqn, NVMF_NQN_SIZE);
+				ret = -EINVAL;
+				goto out;
+			}
+			opts->discovery_nqn =
+				!(strcmp(opts->subsysnqn,
+					 NVME_DISC_SUBSYS_NAME));
+			break;
+		case NVMF_OPT_TRADDR:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			kfree(opts->traddr);
+			opts->traddr = p;
+			break;
+		case NVMF_OPT_TRSVCID:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			kfree(opts->trsvcid);
+			opts->trsvcid = p;
+			break;
+		case NVMF_OPT_QUEUE_SIZE:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out;
+			}
+			if (token < NVMF_MIN_QUEUE_SIZE ||
+			    token > NVMF_MAX_QUEUE_SIZE) {
+				pr_err("Invalid queue_size %d\n", token);
+				ret = -EINVAL;
+				goto out;
+			}
+			opts->queue_size = token;
+			break;
+		case NVMF_OPT_NR_IO_QUEUES:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out;
+			}
+			if (token <= 0) {
+				pr_err("Invalid number of IOQs %d\n", token);
+				ret = -EINVAL;
+				goto out;
+			}
+			if (opts->discovery_nqn) {
+				pr_debug("Ignoring nr_io_queues value for discovery controller\n");
+				break;
+			}
+
+			opts->nr_io_queues = min_t(unsigned int,
+					num_online_cpus(), token);
+			break;
+		case NVMF_OPT_KATO:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out;
+			}
+
+			if (token < 0) {
+				pr_err("Invalid keep_alive_tmo %d\n", token);
+				ret = -EINVAL;
+				goto out;
+			} else if (token == 0 && !opts->discovery_nqn) {
+				/* Allowed for debug */
+				pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
+			}
+			opts->kato = token;
+
+			if (opts->discovery_nqn && opts->kato) {
+				pr_err("Discovery controllers cannot accept KATO != 0\n");
+				ret = -EINVAL;
+				goto out;
+			}
+
+			break;
+		case NVMF_OPT_CTRL_LOSS_TMO:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out;
+			}
+
+			if (token < 0)
+				pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
+			ctrl_loss_tmo = token;
+			break;
+		case NVMF_OPT_HOSTNQN:
+			if (opts->host) {
+				pr_err("hostnqn already user-assigned: %s\n",
+				       opts->host->nqn);
+				ret = -EADDRINUSE;
+				goto out;
+			}
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			nqnlen = strlen(p);
+			if (nqnlen >= NVMF_NQN_SIZE) {
+				pr_err("%s needs to be < %d bytes\n",
+					p, NVMF_NQN_SIZE);
+				kfree(p);
+				ret = -EINVAL;
+				goto out;
+			}
+			nvmf_host_put(opts->host);
+			opts->host = nvmf_host_add(p);
+			kfree(p);
+			if (!opts->host) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			break;
+		case NVMF_OPT_RECONNECT_DELAY:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out;
+			}
+			if (token <= 0) {
+				pr_err("Invalid reconnect_delay %d\n", token);
+				ret = -EINVAL;
+				goto out;
+			}
+			opts->reconnect_delay = token;
+			break;
+		case NVMF_OPT_HOST_TRADDR:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			kfree(opts->host_traddr);
+			opts->host_traddr = p;
+			break;
+		case NVMF_OPT_HOST_ID:
+			p = match_strdup(args);
+			if (!p) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			ret = uuid_parse(p, &hostid);
+			if (ret) {
+				pr_err("Invalid hostid %s\n", p);
+				ret = -EINVAL;
+				kfree(p);
+				goto out;
+			}
+			kfree(p);
+			break;
+		case NVMF_OPT_DUP_CONNECT:
+			opts->duplicate_connect = true;
+			break;
+		default:
+			pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
+				p);
+			ret = -EINVAL;
+			goto out;
+		}
+	}
+
+	if (opts->discovery_nqn) {
+		opts->kato = 0;
+		opts->nr_io_queues = 0;
+		opts->duplicate_connect = true;
+	}
+	if (ctrl_loss_tmo < 0)
+		opts->max_reconnects = -1;
+	else
+		opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
+						opts->reconnect_delay);
+
+	if (!opts->host) {
+		kref_get(&nvmf_default_host->ref);
+		opts->host = nvmf_default_host;
+	}
+
+	uuid_copy(&opts->host->id, &hostid);
+
+out:
+	kfree(options);
+	return ret;
+}
+
+static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
+		unsigned int required_opts)
+{
+	if ((opts->mask & required_opts) != required_opts) {
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
+			if ((opt_tokens[i].token & required_opts) &&
+			    !(opt_tokens[i].token & opts->mask)) {
+				pr_warn("missing parameter '%s'\n",
+					opt_tokens[i].pattern);
+			}
+		}
+
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
+		unsigned int allowed_opts)
+{
+	if (opts->mask & ~allowed_opts) {
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
+			if ((opt_tokens[i].token & opts->mask) &&
+			    (opt_tokens[i].token & ~allowed_opts)) {
+				pr_warn("invalid parameter '%s'\n",
+					opt_tokens[i].pattern);
+			}
+		}
+
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void nvmf_free_options(struct nvmf_ctrl_options *opts)
+{
+	nvmf_host_put(opts->host);
+	kfree(opts->transport);
+	kfree(opts->traddr);
+	kfree(opts->trsvcid);
+	kfree(opts->subsysnqn);
+	kfree(opts->host_traddr);
+	kfree(opts);
+}
+EXPORT_SYMBOL_GPL(nvmf_free_options);
+
+#define NVMF_REQUIRED_OPTS	(NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
+#define NVMF_ALLOWED_OPTS	(NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
+				 NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
+				 NVMF_OPT_HOST_ID | NVMF_OPT_DUP_CONNECT)
+
+static struct nvme_ctrl *
+nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
+{
+	struct nvmf_ctrl_options *opts;
+	struct nvmf_transport_ops *ops;
+	struct nvme_ctrl *ctrl;
+	int ret;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return ERR_PTR(-ENOMEM);
+
+	ret = nvmf_parse_options(opts, buf);
+	if (ret)
+		goto out_free_opts;
+
+
+	request_module("nvme-%s", opts->transport);
+
+	/*
+	 * Check the generic options first as we need a valid transport for
+	 * the lookup below.  Then clear the generic flags so that transport
+	 * drivers don't have to care about them.
+	 */
+	ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
+	if (ret)
+		goto out_free_opts;
+	opts->mask &= ~NVMF_REQUIRED_OPTS;
+
+	down_read(&nvmf_transports_rwsem);
+	ops = nvmf_lookup_transport(opts);
+	if (!ops) {
+		pr_info("no handler found for transport %s.\n",
+			opts->transport);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	if (!try_module_get(ops->module)) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	up_read(&nvmf_transports_rwsem);
+
+	ret = nvmf_check_required_opts(opts, ops->required_opts);
+	if (ret)
+		goto out_module_put;
+	ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
+				ops->allowed_opts | ops->required_opts);
+	if (ret)
+		goto out_module_put;
+
+	ctrl = ops->create_ctrl(dev, opts);
+	if (IS_ERR(ctrl)) {
+		ret = PTR_ERR(ctrl);
+		goto out_module_put;
+	}
+
+	module_put(ops->module);
+	return ctrl;
+
+out_module_put:
+	module_put(ops->module);
+	goto out_free_opts;
+out_unlock:
+	up_read(&nvmf_transports_rwsem);
+out_free_opts:
+	nvmf_free_options(opts);
+	return ERR_PTR(ret);
+}
+
+static struct class *nvmf_class;
+static struct device *nvmf_device;
+static DEFINE_MUTEX(nvmf_dev_mutex);
+
+static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
+		size_t count, loff_t *pos)
+{
+	struct seq_file *seq_file = file->private_data;
+	struct nvme_ctrl *ctrl;
+	const char *buf;
+	int ret = 0;
+
+	if (count > PAGE_SIZE)
+		return -ENOMEM;
+
+	buf = memdup_user_nul(ubuf, count);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	mutex_lock(&nvmf_dev_mutex);
+	if (seq_file->private) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
+	if (IS_ERR(ctrl)) {
+		ret = PTR_ERR(ctrl);
+		goto out_unlock;
+	}
+
+	seq_file->private = ctrl;
+
+out_unlock:
+	mutex_unlock(&nvmf_dev_mutex);
+	kfree(buf);
+	return ret ? ret : count;
+}
+
+static int nvmf_dev_show(struct seq_file *seq_file, void *private)
+{
+	struct nvme_ctrl *ctrl;
+	int ret = 0;
+
+	mutex_lock(&nvmf_dev_mutex);
+	ctrl = seq_file->private;
+	if (!ctrl) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	seq_printf(seq_file, "instance=%d,cntlid=%d\n",
+			ctrl->instance, ctrl->cntlid);
+
+out_unlock:
+	mutex_unlock(&nvmf_dev_mutex);
+	return ret;
+}
+
+static int nvmf_dev_open(struct inode *inode, struct file *file)
+{
+	/*
+	 * The miscdevice code initializes file->private_data, but doesn't
+	 * make use of it later.
+	 */
+	file->private_data = NULL;
+	return single_open(file, nvmf_dev_show, NULL);
+}
+
+static int nvmf_dev_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq_file = file->private_data;
+	struct nvme_ctrl *ctrl = seq_file->private;
+
+	if (ctrl)
+		nvme_put_ctrl(ctrl);
+	return single_release(inode, file);
+}
+
+static const struct file_operations nvmf_dev_fops = {
+	.owner		= THIS_MODULE,
+	.write		= nvmf_dev_write,
+	.read		= seq_read,
+	.open		= nvmf_dev_open,
+	.release	= nvmf_dev_release,
+};
+
+static struct miscdevice nvmf_misc = {
+	.minor		= MISC_DYNAMIC_MINOR,
+	.name           = "nvme-fabrics",
+	.fops		= &nvmf_dev_fops,
+};
+
+static int __init nvmf_init(void)
+{
+	int ret;
+
+	nvmf_default_host = nvmf_host_default();
+	if (!nvmf_default_host)
+		return -ENOMEM;
+
+	nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
+	if (IS_ERR(nvmf_class)) {
+		pr_err("couldn't register class nvme-fabrics\n");
+		ret = PTR_ERR(nvmf_class);
+		goto out_free_host;
+	}
+
+	nvmf_device =
+		device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
+	if (IS_ERR(nvmf_device)) {
+		pr_err("couldn't create nvme-fabris device!\n");
+		ret = PTR_ERR(nvmf_device);
+		goto out_destroy_class;
+	}
+
+	ret = misc_register(&nvmf_misc);
+	if (ret) {
+		pr_err("couldn't register misc device: %d\n", ret);
+		goto out_destroy_device;
+	}
+
+	return 0;
+
+out_destroy_device:
+	device_destroy(nvmf_class, MKDEV(0, 0));
+out_destroy_class:
+	class_destroy(nvmf_class);
+out_free_host:
+	nvmf_host_put(nvmf_default_host);
+	return ret;
+}
+
+static void __exit nvmf_exit(void)
+{
+	misc_deregister(&nvmf_misc);
+	device_destroy(nvmf_class, MKDEV(0, 0));
+	class_destroy(nvmf_class);
+	nvmf_host_put(nvmf_default_host);
+
+	BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
+	BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
+	BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
+	BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
+}
+
+MODULE_LICENSE("GPL v2");
+
+module_init(nvmf_init);
+module_exit(nvmf_exit);
diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
new file mode 100644
index 000000000..aa2fdb2a2
--- /dev/null
+++ b/drivers/nvme/host/fabrics.h
@@ -0,0 +1,179 @@
+/*
+ * NVMe over Fabrics common host code.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#ifndef _NVME_FABRICS_H
+#define _NVME_FABRICS_H 1
+
+#include <linux/in.h>
+#include <linux/inet.h>
+
+#define NVMF_MIN_QUEUE_SIZE	16
+#define NVMF_MAX_QUEUE_SIZE	1024
+#define NVMF_DEF_QUEUE_SIZE	128
+#define NVMF_DEF_RECONNECT_DELAY	10
+/* default to 600 seconds of reconnect attempts before giving up */
+#define NVMF_DEF_CTRL_LOSS_TMO		600
+
+/*
+ * Define a host as seen by the target.  We allocate one at boot, but also
+ * allow the override it when creating controllers.  This is both to provide
+ * persistence of the Host NQN over multiple boots, and to allow using
+ * multiple ones, for example in a container scenario.  Because we must not
+ * use different Host NQNs with the same Host ID we generate a Host ID and
+ * use this structure to keep track of the relation between the two.
+ */
+struct nvmf_host {
+	struct kref		ref;
+	struct list_head	list;
+	char			nqn[NVMF_NQN_SIZE];
+	uuid_t			id;
+};
+
+/**
+ * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
+ */
+enum {
+	NVMF_OPT_ERR		= 0,
+	NVMF_OPT_TRANSPORT	= 1 << 0,
+	NVMF_OPT_NQN		= 1 << 1,
+	NVMF_OPT_TRADDR		= 1 << 2,
+	NVMF_OPT_TRSVCID	= 1 << 3,
+	NVMF_OPT_QUEUE_SIZE	= 1 << 4,
+	NVMF_OPT_NR_IO_QUEUES	= 1 << 5,
+	NVMF_OPT_TL_RETRY_COUNT	= 1 << 6,
+	NVMF_OPT_KATO		= 1 << 7,
+	NVMF_OPT_HOSTNQN	= 1 << 8,
+	NVMF_OPT_RECONNECT_DELAY = 1 << 9,
+	NVMF_OPT_HOST_TRADDR	= 1 << 10,
+	NVMF_OPT_CTRL_LOSS_TMO	= 1 << 11,
+	NVMF_OPT_HOST_ID	= 1 << 12,
+	NVMF_OPT_DUP_CONNECT	= 1 << 13,
+};
+
+/**
+ * struct nvmf_ctrl_options - Used to hold the options specified
+ *			      with the parsing opts enum.
+ * @mask:	Used by the fabrics library to parse through sysfs options
+ *		on adding a NVMe controller.
+ * @transport:	Holds the fabric transport "technology name" (for a lack of
+ *		better description) that will be used by an NVMe controller
+ *		being added.
+ * @subsysnqn:	Hold the fully qualified NQN subystem name (format defined
+ *		in the NVMe specification, "NVMe Qualified Names").
+ * @traddr:	The transport-specific TRADDR field for a port on the
+ *              subsystem which is adding a controller.
+ * @trsvcid:	The transport-specific TRSVCID field for a port on the
+ *              subsystem which is adding a controller.
+ * @host_traddr: A transport-specific field identifying the NVME host port
+ *              to use for the connection to the controller.
+ * @queue_size: Number of IO queue elements.
+ * @nr_io_queues: Number of controller IO queues that will be established.
+ * @reconnect_delay: Time between two consecutive reconnect attempts.
+ * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
+ * @kato:	Keep-alive timeout.
+ * @host:	Virtual NVMe host, contains the NQN and Host ID.
+ * @max_reconnects: maximum number of allowed reconnect attempts before removing
+ *              the controller, (-1) means reconnect forever, zero means remove
+ *              immediately;
+ */
+struct nvmf_ctrl_options {
+	unsigned		mask;
+	char			*transport;
+	char			*subsysnqn;
+	char			*traddr;
+	char			*trsvcid;
+	char			*host_traddr;
+	size_t			queue_size;
+	unsigned int		nr_io_queues;
+	unsigned int		reconnect_delay;
+	bool			discovery_nqn;
+	bool			duplicate_connect;
+	unsigned int		kato;
+	struct nvmf_host	*host;
+	int			max_reconnects;
+};
+
+/*
+ * struct nvmf_transport_ops - used to register a specific
+ *			       fabric implementation of NVMe fabrics.
+ * @entry:		Used by the fabrics library to add the new
+ *			registration entry to its linked-list internal tree.
+ * @module:             Transport module reference
+ * @name:		Name of the NVMe fabric driver implementation.
+ * @required_opts:	sysfs command-line options that must be specified
+ *			when adding a new NVMe controller.
+ * @allowed_opts:	sysfs command-line options that can be specified
+ *			when adding a new NVMe controller.
+ * @create_ctrl():	function pointer that points to a non-NVMe
+ *			implementation-specific fabric technology
+ *			that would go into starting up that fabric
+ *			for the purpose of conneciton to an NVMe controller
+ *			using that fabric technology.
+ *
+ * Notes:
+ *	1. At minimum, 'required_opts' and 'allowed_opts' should
+ *	   be set to the same enum parsing options defined earlier.
+ *	2. create_ctrl() must be defined (even if it does nothing)
+ *	3. struct nvmf_transport_ops must be statically allocated in the
+ *	   modules .bss section so that a pure module_get on @module
+ *	   prevents the memory from beeing freed.
+ */
+struct nvmf_transport_ops {
+	struct list_head	entry;
+	struct module		*module;
+	const char		*name;
+	int			required_opts;
+	int			allowed_opts;
+	struct nvme_ctrl	*(*create_ctrl)(struct device *dev,
+					struct nvmf_ctrl_options *opts);
+};
+
+static inline bool
+nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
+			struct nvmf_ctrl_options *opts)
+{
+	if (ctrl->state == NVME_CTRL_DELETING ||
+	    ctrl->state == NVME_CTRL_DEAD ||
+	    strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
+	    strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
+	    memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t)))
+		return false;
+
+	return true;
+}
+
+int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
+int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
+int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
+int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
+int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
+int nvmf_register_transport(struct nvmf_transport_ops *ops);
+void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
+void nvmf_free_options(struct nvmf_ctrl_options *opts);
+int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
+bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
+blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl,
+		struct request *rq);
+bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
+		bool queue_live);
+
+static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
+		bool queue_live)
+{
+	if (likely(ctrl->state == NVME_CTRL_LIVE ||
+		   ctrl->state == NVME_CTRL_ADMIN_ONLY))
+		return true;
+	return __nvmf_check_ready(ctrl, rq, queue_live);
+}
+
+#endif /* _NVME_FABRICS_H */
diff --git a/drivers/nvme/host/fault_inject.c b/drivers/nvme/host/fault_inject.c
new file mode 100644
index 000000000..02632266a
--- /dev/null
+++ b/drivers/nvme/host/fault_inject.c
@@ -0,0 +1,79 @@
+/*
+ * fault injection support for nvme.
+ *
+ * Copyright (c) 2018, Oracle and/or its affiliates
+ *
+ */
+
+#include <linux/moduleparam.h>
+#include "nvme.h"
+
+static DECLARE_FAULT_ATTR(fail_default_attr);
+/* optional fault injection attributes boot time option:
+ * nvme_core.fail_request=<interval>,<probability>,<space>,<times>
+ */
+static char *fail_request;
+module_param(fail_request, charp, 0000);
+
+void nvme_fault_inject_init(struct nvme_ns *ns)
+{
+	struct dentry *dir, *parent;
+	char *name = ns->disk->disk_name;
+	struct nvme_fault_inject *fault_inj = &ns->fault_inject;
+	struct fault_attr *attr = &fault_inj->attr;
+
+	/* set default fault injection attribute */
+	if (fail_request)
+		setup_fault_attr(&fail_default_attr, fail_request);
+
+	/* create debugfs directory and attribute */
+	parent = debugfs_create_dir(name, NULL);
+	if (!parent) {
+		pr_warn("%s: failed to create debugfs directory\n", name);
+		return;
+	}
+
+	*attr = fail_default_attr;
+	dir = fault_create_debugfs_attr("fault_inject", parent, attr);
+	if (IS_ERR(dir)) {
+		pr_warn("%s: failed to create debugfs attr\n", name);
+		debugfs_remove_recursive(parent);
+		return;
+	}
+	ns->fault_inject.parent = parent;
+
+	/* create debugfs for status code and dont_retry */
+	fault_inj->status = NVME_SC_INVALID_OPCODE;
+	fault_inj->dont_retry = true;
+	debugfs_create_x16("status", 0600, dir,	&fault_inj->status);
+	debugfs_create_bool("dont_retry", 0600, dir, &fault_inj->dont_retry);
+}
+
+void nvme_fault_inject_fini(struct nvme_ns *ns)
+{
+	/* remove debugfs directories */
+	debugfs_remove_recursive(ns->fault_inject.parent);
+}
+
+void nvme_should_fail(struct request *req)
+{
+	struct gendisk *disk = req->rq_disk;
+	struct nvme_ns *ns = NULL;
+	u16 status;
+
+	/*
+	 * make sure this request is coming from a valid namespace
+	 */
+	if (!disk)
+		return;
+
+	ns = disk->private_data;
+	if (ns && should_fail(&ns->fault_inject.attr, 1)) {
+		/* inject status code and DNR bit */
+		status = ns->fault_inject.status;
+		if (ns->fault_inject.dont_retry)
+			status |= NVME_SC_DNR;
+		nvme_req(req)->status =	status;
+	}
+}
+EXPORT_SYMBOL_GPL(nvme_should_fail);
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
new file mode 100644
index 000000000..ed88d5021
--- /dev/null
+++ b/drivers/nvme/host/fc.c
@@ -0,0 +1,3410 @@
+/*
+ * Copyright (c) 2016 Avago Technologies.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful.
+ * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
+ * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED, EXCEPT TO
+ * THE EXTENT THAT SUCH DISCLAIMERS ARE HELD TO BE LEGALLY INVALID.
+ * See the GNU General Public License for more details, a copy of which
+ * can be found in the file COPYING included with this package
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/module.h>
+#include <linux/parser.h>
+#include <uapi/scsi/fc/fc_fs.h>
+#include <uapi/scsi/fc/fc_els.h>
+#include <linux/delay.h>
+
+#include "nvme.h"
+#include "fabrics.h"
+#include <linux/nvme-fc-driver.h>
+#include <linux/nvme-fc.h>
+
+
+/* *************************** Data Structures/Defines ****************** */
+
+
+enum nvme_fc_queue_flags {
+	NVME_FC_Q_CONNECTED = 0,
+	NVME_FC_Q_LIVE,
+};
+
+#define NVME_FC_DEFAULT_DEV_LOSS_TMO	60	/* seconds */
+
+struct nvme_fc_queue {
+	struct nvme_fc_ctrl	*ctrl;
+	struct device		*dev;
+	struct blk_mq_hw_ctx	*hctx;
+	void			*lldd_handle;
+	size_t			cmnd_capsule_len;
+	u32			qnum;
+	u32			rqcnt;
+	u32			seqno;
+
+	u64			connection_id;
+	atomic_t		csn;
+
+	unsigned long		flags;
+} __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
+
+enum nvme_fcop_flags {
+	FCOP_FLAGS_TERMIO	= (1 << 0),
+	FCOP_FLAGS_AEN		= (1 << 1),
+};
+
+struct nvmefc_ls_req_op {
+	struct nvmefc_ls_req	ls_req;
+
+	struct nvme_fc_rport	*rport;
+	struct nvme_fc_queue	*queue;
+	struct request		*rq;
+	u32			flags;
+
+	int			ls_error;
+	struct completion	ls_done;
+	struct list_head	lsreq_list;	/* rport->ls_req_list */
+	bool			req_queued;
+};
+
+enum nvme_fcpop_state {
+	FCPOP_STATE_UNINIT	= 0,
+	FCPOP_STATE_IDLE	= 1,
+	FCPOP_STATE_ACTIVE	= 2,
+	FCPOP_STATE_ABORTED	= 3,
+	FCPOP_STATE_COMPLETE	= 4,
+};
+
+struct nvme_fc_fcp_op {
+	struct nvme_request	nreq;		/*
+						 * nvme/host/core.c
+						 * requires this to be
+						 * the 1st element in the
+						 * private structure
+						 * associated with the
+						 * request.
+						 */
+	struct nvmefc_fcp_req	fcp_req;
+
+	struct nvme_fc_ctrl	*ctrl;
+	struct nvme_fc_queue	*queue;
+	struct request		*rq;
+
+	atomic_t		state;
+	u32			flags;
+	u32			rqno;
+	u32			nents;
+
+	struct nvme_fc_cmd_iu	cmd_iu;
+	struct nvme_fc_ersp_iu	rsp_iu;
+};
+
+struct nvme_fc_lport {
+	struct nvme_fc_local_port	localport;
+
+	struct ida			endp_cnt;
+	struct list_head		port_list;	/* nvme_fc_port_list */
+	struct list_head		endp_list;
+	struct device			*dev;	/* physical device for dma */
+	struct nvme_fc_port_template	*ops;
+	struct kref			ref;
+	atomic_t                        act_rport_cnt;
+} __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
+
+struct nvme_fc_rport {
+	struct nvme_fc_remote_port	remoteport;
+
+	struct list_head		endp_list; /* for lport->endp_list */
+	struct list_head		ctrl_list;
+	struct list_head		ls_req_list;
+	struct device			*dev;	/* physical device for dma */
+	struct nvme_fc_lport		*lport;
+	spinlock_t			lock;
+	struct kref			ref;
+	atomic_t                        act_ctrl_cnt;
+	unsigned long			dev_loss_end;
+} __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
+
+enum nvme_fcctrl_flags {
+	FCCTRL_TERMIO		= (1 << 0),
+};
+
+struct nvme_fc_ctrl {
+	spinlock_t		lock;
+	struct nvme_fc_queue	*queues;
+	struct device		*dev;
+	struct nvme_fc_lport	*lport;
+	struct nvme_fc_rport	*rport;
+	u32			cnum;
+
+	bool			ioq_live;
+	bool			assoc_active;
+	atomic_t		err_work_active;
+	u64			association_id;
+
+	struct list_head	ctrl_list;	/* rport->ctrl_list */
+
+	struct blk_mq_tag_set	admin_tag_set;
+	struct blk_mq_tag_set	tag_set;
+
+	struct delayed_work	connect_work;
+	struct work_struct	err_work;
+
+	struct kref		ref;
+	u32			flags;
+	u32			iocnt;
+	wait_queue_head_t	ioabort_wait;
+
+	struct nvme_fc_fcp_op	aen_ops[NVME_NR_AEN_COMMANDS];
+
+	struct nvme_ctrl	ctrl;
+};
+
+static inline struct nvme_fc_ctrl *
+to_fc_ctrl(struct nvme_ctrl *ctrl)
+{
+	return container_of(ctrl, struct nvme_fc_ctrl, ctrl);
+}
+
+static inline struct nvme_fc_lport *
+localport_to_lport(struct nvme_fc_local_port *portptr)
+{
+	return container_of(portptr, struct nvme_fc_lport, localport);
+}
+
+static inline struct nvme_fc_rport *
+remoteport_to_rport(struct nvme_fc_remote_port *portptr)
+{
+	return container_of(portptr, struct nvme_fc_rport, remoteport);
+}
+
+static inline struct nvmefc_ls_req_op *
+ls_req_to_lsop(struct nvmefc_ls_req *lsreq)
+{
+	return container_of(lsreq, struct nvmefc_ls_req_op, ls_req);
+}
+
+static inline struct nvme_fc_fcp_op *
+fcp_req_to_fcp_op(struct nvmefc_fcp_req *fcpreq)
+{
+	return container_of(fcpreq, struct nvme_fc_fcp_op, fcp_req);
+}
+
+
+
+/* *************************** Globals **************************** */
+
+
+static DEFINE_SPINLOCK(nvme_fc_lock);
+
+static LIST_HEAD(nvme_fc_lport_list);
+static DEFINE_IDA(nvme_fc_local_port_cnt);
+static DEFINE_IDA(nvme_fc_ctrl_cnt);
+
+static struct workqueue_struct *nvme_fc_wq;
+
+/*
+ * These items are short-term. They will eventually be moved into
+ * a generic FC class. See comments in module init.
+ */
+static struct class *fc_class;
+static struct device *fc_udev_device;
+
+
+/* *********************** FC-NVME Port Management ************************ */
+
+static void __nvme_fc_delete_hw_queue(struct nvme_fc_ctrl *,
+			struct nvme_fc_queue *, unsigned int);
+
+static void
+nvme_fc_free_lport(struct kref *ref)
+{
+	struct nvme_fc_lport *lport =
+		container_of(ref, struct nvme_fc_lport, ref);
+	unsigned long flags;
+
+	WARN_ON(lport->localport.port_state != FC_OBJSTATE_DELETED);
+	WARN_ON(!list_empty(&lport->endp_list));
+
+	/* remove from transport list */
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	list_del(&lport->port_list);
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	ida_simple_remove(&nvme_fc_local_port_cnt, lport->localport.port_num);
+	ida_destroy(&lport->endp_cnt);
+
+	put_device(lport->dev);
+
+	kfree(lport);
+}
+
+static void
+nvme_fc_lport_put(struct nvme_fc_lport *lport)
+{
+	kref_put(&lport->ref, nvme_fc_free_lport);
+}
+
+static int
+nvme_fc_lport_get(struct nvme_fc_lport *lport)
+{
+	return kref_get_unless_zero(&lport->ref);
+}
+
+
+static struct nvme_fc_lport *
+nvme_fc_attach_to_unreg_lport(struct nvme_fc_port_info *pinfo,
+			struct nvme_fc_port_template *ops,
+			struct device *dev)
+{
+	struct nvme_fc_lport *lport;
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+
+	list_for_each_entry(lport, &nvme_fc_lport_list, port_list) {
+		if (lport->localport.node_name != pinfo->node_name ||
+		    lport->localport.port_name != pinfo->port_name)
+			continue;
+
+		if (lport->dev != dev) {
+			lport = ERR_PTR(-EXDEV);
+			goto out_done;
+		}
+
+		if (lport->localport.port_state != FC_OBJSTATE_DELETED) {
+			lport = ERR_PTR(-EEXIST);
+			goto out_done;
+		}
+
+		if (!nvme_fc_lport_get(lport)) {
+			/*
+			 * fails if ref cnt already 0. If so,
+			 * act as if lport already deleted
+			 */
+			lport = NULL;
+			goto out_done;
+		}
+
+		/* resume the lport */
+
+		lport->ops = ops;
+		lport->localport.port_role = pinfo->port_role;
+		lport->localport.port_id = pinfo->port_id;
+		lport->localport.port_state = FC_OBJSTATE_ONLINE;
+
+		spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+		return lport;
+	}
+
+	lport = NULL;
+
+out_done:
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	return lport;
+}
+
+/**
+ * nvme_fc_register_localport - transport entry point called by an
+ *                              LLDD to register the existence of a NVME
+ *                              host FC port.
+ * @pinfo:     pointer to information about the port to be registered
+ * @template:  LLDD entrypoints and operational parameters for the port
+ * @dev:       physical hardware device node port corresponds to. Will be
+ *             used for DMA mappings
+ * @lport_p:   pointer to a local port pointer. Upon success, the routine
+ *             will allocate a nvme_fc_local_port structure and place its
+ *             address in the local port pointer. Upon failure, local port
+ *             pointer will be set to 0.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvme_fc_register_localport(struct nvme_fc_port_info *pinfo,
+			struct nvme_fc_port_template *template,
+			struct device *dev,
+			struct nvme_fc_local_port **portptr)
+{
+	struct nvme_fc_lport *newrec;
+	unsigned long flags;
+	int ret, idx;
+
+	if (!template->localport_delete || !template->remoteport_delete ||
+	    !template->ls_req || !template->fcp_io ||
+	    !template->ls_abort || !template->fcp_abort ||
+	    !template->max_hw_queues || !template->max_sgl_segments ||
+	    !template->max_dif_sgl_segments || !template->dma_boundary) {
+		ret = -EINVAL;
+		goto out_reghost_failed;
+	}
+
+	/*
+	 * look to see if there is already a localport that had been
+	 * deregistered and in the process of waiting for all the
+	 * references to fully be removed.  If the references haven't
+	 * expired, we can simply re-enable the localport. Remoteports
+	 * and controller reconnections should resume naturally.
+	 */
+	newrec = nvme_fc_attach_to_unreg_lport(pinfo, template, dev);
+
+	/* found an lport, but something about its state is bad */
+	if (IS_ERR(newrec)) {
+		ret = PTR_ERR(newrec);
+		goto out_reghost_failed;
+
+	/* found existing lport, which was resumed */
+	} else if (newrec) {
+		*portptr = &newrec->localport;
+		return 0;
+	}
+
+	/* nothing found - allocate a new localport struct */
+
+	newrec = kmalloc((sizeof(*newrec) + template->local_priv_sz),
+			 GFP_KERNEL);
+	if (!newrec) {
+		ret = -ENOMEM;
+		goto out_reghost_failed;
+	}
+
+	idx = ida_simple_get(&nvme_fc_local_port_cnt, 0, 0, GFP_KERNEL);
+	if (idx < 0) {
+		ret = -ENOSPC;
+		goto out_fail_kfree;
+	}
+
+	if (!get_device(dev) && dev) {
+		ret = -ENODEV;
+		goto out_ida_put;
+	}
+
+	INIT_LIST_HEAD(&newrec->port_list);
+	INIT_LIST_HEAD(&newrec->endp_list);
+	kref_init(&newrec->ref);
+	atomic_set(&newrec->act_rport_cnt, 0);
+	newrec->ops = template;
+	newrec->dev = dev;
+	ida_init(&newrec->endp_cnt);
+	newrec->localport.private = &newrec[1];
+	newrec->localport.node_name = pinfo->node_name;
+	newrec->localport.port_name = pinfo->port_name;
+	newrec->localport.port_role = pinfo->port_role;
+	newrec->localport.port_id = pinfo->port_id;
+	newrec->localport.port_state = FC_OBJSTATE_ONLINE;
+	newrec->localport.port_num = idx;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	list_add_tail(&newrec->port_list, &nvme_fc_lport_list);
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	if (dev)
+		dma_set_seg_boundary(dev, template->dma_boundary);
+
+	*portptr = &newrec->localport;
+	return 0;
+
+out_ida_put:
+	ida_simple_remove(&nvme_fc_local_port_cnt, idx);
+out_fail_kfree:
+	kfree(newrec);
+out_reghost_failed:
+	*portptr = NULL;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_register_localport);
+
+/**
+ * nvme_fc_unregister_localport - transport entry point called by an
+ *                              LLDD to deregister/remove a previously
+ *                              registered a NVME host FC port.
+ * @localport: pointer to the (registered) local port that is to be
+ *             deregistered.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvme_fc_unregister_localport(struct nvme_fc_local_port *portptr)
+{
+	struct nvme_fc_lport *lport = localport_to_lport(portptr);
+	unsigned long flags;
+
+	if (!portptr)
+		return -EINVAL;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+
+	if (portptr->port_state != FC_OBJSTATE_ONLINE) {
+		spin_unlock_irqrestore(&nvme_fc_lock, flags);
+		return -EINVAL;
+	}
+	portptr->port_state = FC_OBJSTATE_DELETED;
+
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	if (atomic_read(&lport->act_rport_cnt) == 0)
+		lport->ops->localport_delete(&lport->localport);
+
+	nvme_fc_lport_put(lport);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_unregister_localport);
+
+/*
+ * TRADDR strings, per FC-NVME are fixed format:
+ *   "nn-0x<16hexdigits>:pn-0x<16hexdigits>" - 43 characters
+ * udev event will only differ by prefix of what field is
+ * being specified:
+ *    "NVMEFC_HOST_TRADDR=" or "NVMEFC_TRADDR=" - 19 max characters
+ *  19 + 43 + null_fudge = 64 characters
+ */
+#define FCNVME_TRADDR_LENGTH		64
+
+static void
+nvme_fc_signal_discovery_scan(struct nvme_fc_lport *lport,
+		struct nvme_fc_rport *rport)
+{
+	char hostaddr[FCNVME_TRADDR_LENGTH];	/* NVMEFC_HOST_TRADDR=...*/
+	char tgtaddr[FCNVME_TRADDR_LENGTH];	/* NVMEFC_TRADDR=...*/
+	char *envp[4] = { "FC_EVENT=nvmediscovery", hostaddr, tgtaddr, NULL };
+
+	if (!(rport->remoteport.port_role & FC_PORT_ROLE_NVME_DISCOVERY))
+		return;
+
+	snprintf(hostaddr, sizeof(hostaddr),
+		"NVMEFC_HOST_TRADDR=nn-0x%016llx:pn-0x%016llx",
+		lport->localport.node_name, lport->localport.port_name);
+	snprintf(tgtaddr, sizeof(tgtaddr),
+		"NVMEFC_TRADDR=nn-0x%016llx:pn-0x%016llx",
+		rport->remoteport.node_name, rport->remoteport.port_name);
+	kobject_uevent_env(&fc_udev_device->kobj, KOBJ_CHANGE, envp);
+}
+
+static void
+nvme_fc_free_rport(struct kref *ref)
+{
+	struct nvme_fc_rport *rport =
+		container_of(ref, struct nvme_fc_rport, ref);
+	struct nvme_fc_lport *lport =
+			localport_to_lport(rport->remoteport.localport);
+	unsigned long flags;
+
+	WARN_ON(rport->remoteport.port_state != FC_OBJSTATE_DELETED);
+	WARN_ON(!list_empty(&rport->ctrl_list));
+
+	/* remove from lport list */
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	list_del(&rport->endp_list);
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	ida_simple_remove(&lport->endp_cnt, rport->remoteport.port_num);
+
+	kfree(rport);
+
+	nvme_fc_lport_put(lport);
+}
+
+static void
+nvme_fc_rport_put(struct nvme_fc_rport *rport)
+{
+	kref_put(&rport->ref, nvme_fc_free_rport);
+}
+
+static int
+nvme_fc_rport_get(struct nvme_fc_rport *rport)
+{
+	return kref_get_unless_zero(&rport->ref);
+}
+
+static void
+nvme_fc_resume_controller(struct nvme_fc_ctrl *ctrl)
+{
+	switch (ctrl->ctrl.state) {
+	case NVME_CTRL_NEW:
+	case NVME_CTRL_CONNECTING:
+		/*
+		 * As all reconnects were suppressed, schedule a
+		 * connect.
+		 */
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: connectivity re-established. "
+			"Attempting reconnect\n", ctrl->cnum);
+
+		queue_delayed_work(nvme_wq, &ctrl->connect_work, 0);
+		break;
+
+	case NVME_CTRL_RESETTING:
+		/*
+		 * Controller is already in the process of terminating the
+		 * association. No need to do anything further. The reconnect
+		 * step will naturally occur after the reset completes.
+		 */
+		break;
+
+	default:
+		/* no action to take - let it delete */
+		break;
+	}
+}
+
+static struct nvme_fc_rport *
+nvme_fc_attach_to_suspended_rport(struct nvme_fc_lport *lport,
+				struct nvme_fc_port_info *pinfo)
+{
+	struct nvme_fc_rport *rport;
+	struct nvme_fc_ctrl *ctrl;
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+
+	list_for_each_entry(rport, &lport->endp_list, endp_list) {
+		if (rport->remoteport.node_name != pinfo->node_name ||
+		    rport->remoteport.port_name != pinfo->port_name)
+			continue;
+
+		if (!nvme_fc_rport_get(rport)) {
+			rport = ERR_PTR(-ENOLCK);
+			goto out_done;
+		}
+
+		spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+		spin_lock_irqsave(&rport->lock, flags);
+
+		/* has it been unregistered */
+		if (rport->remoteport.port_state != FC_OBJSTATE_DELETED) {
+			/* means lldd called us twice */
+			spin_unlock_irqrestore(&rport->lock, flags);
+			nvme_fc_rport_put(rport);
+			return ERR_PTR(-ESTALE);
+		}
+
+		rport->remoteport.port_role = pinfo->port_role;
+		rport->remoteport.port_id = pinfo->port_id;
+		rport->remoteport.port_state = FC_OBJSTATE_ONLINE;
+		rport->dev_loss_end = 0;
+
+		/*
+		 * kick off a reconnect attempt on all associations to the
+		 * remote port. A successful reconnects will resume i/o.
+		 */
+		list_for_each_entry(ctrl, &rport->ctrl_list, ctrl_list)
+			nvme_fc_resume_controller(ctrl);
+
+		spin_unlock_irqrestore(&rport->lock, flags);
+
+		return rport;
+	}
+
+	rport = NULL;
+
+out_done:
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	return rport;
+}
+
+static inline void
+__nvme_fc_set_dev_loss_tmo(struct nvme_fc_rport *rport,
+			struct nvme_fc_port_info *pinfo)
+{
+	if (pinfo->dev_loss_tmo)
+		rport->remoteport.dev_loss_tmo = pinfo->dev_loss_tmo;
+	else
+		rport->remoteport.dev_loss_tmo = NVME_FC_DEFAULT_DEV_LOSS_TMO;
+}
+
+/**
+ * nvme_fc_register_remoteport - transport entry point called by an
+ *                              LLDD to register the existence of a NVME
+ *                              subsystem FC port on its fabric.
+ * @localport: pointer to the (registered) local port that the remote
+ *             subsystem port is connected to.
+ * @pinfo:     pointer to information about the port to be registered
+ * @rport_p:   pointer to a remote port pointer. Upon success, the routine
+ *             will allocate a nvme_fc_remote_port structure and place its
+ *             address in the remote port pointer. Upon failure, remote port
+ *             pointer will be set to 0.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvme_fc_register_remoteport(struct nvme_fc_local_port *localport,
+				struct nvme_fc_port_info *pinfo,
+				struct nvme_fc_remote_port **portptr)
+{
+	struct nvme_fc_lport *lport = localport_to_lport(localport);
+	struct nvme_fc_rport *newrec;
+	unsigned long flags;
+	int ret, idx;
+
+	if (!nvme_fc_lport_get(lport)) {
+		ret = -ESHUTDOWN;
+		goto out_reghost_failed;
+	}
+
+	/*
+	 * look to see if there is already a remoteport that is waiting
+	 * for a reconnect (within dev_loss_tmo) with the same WWN's.
+	 * If so, transition to it and reconnect.
+	 */
+	newrec = nvme_fc_attach_to_suspended_rport(lport, pinfo);
+
+	/* found an rport, but something about its state is bad */
+	if (IS_ERR(newrec)) {
+		ret = PTR_ERR(newrec);
+		goto out_lport_put;
+
+	/* found existing rport, which was resumed */
+	} else if (newrec) {
+		nvme_fc_lport_put(lport);
+		__nvme_fc_set_dev_loss_tmo(newrec, pinfo);
+		nvme_fc_signal_discovery_scan(lport, newrec);
+		*portptr = &newrec->remoteport;
+		return 0;
+	}
+
+	/* nothing found - allocate a new remoteport struct */
+
+	newrec = kmalloc((sizeof(*newrec) + lport->ops->remote_priv_sz),
+			 GFP_KERNEL);
+	if (!newrec) {
+		ret = -ENOMEM;
+		goto out_lport_put;
+	}
+
+	idx = ida_simple_get(&lport->endp_cnt, 0, 0, GFP_KERNEL);
+	if (idx < 0) {
+		ret = -ENOSPC;
+		goto out_kfree_rport;
+	}
+
+	INIT_LIST_HEAD(&newrec->endp_list);
+	INIT_LIST_HEAD(&newrec->ctrl_list);
+	INIT_LIST_HEAD(&newrec->ls_req_list);
+	kref_init(&newrec->ref);
+	atomic_set(&newrec->act_ctrl_cnt, 0);
+	spin_lock_init(&newrec->lock);
+	newrec->remoteport.localport = &lport->localport;
+	newrec->dev = lport->dev;
+	newrec->lport = lport;
+	newrec->remoteport.private = &newrec[1];
+	newrec->remoteport.port_role = pinfo->port_role;
+	newrec->remoteport.node_name = pinfo->node_name;
+	newrec->remoteport.port_name = pinfo->port_name;
+	newrec->remoteport.port_id = pinfo->port_id;
+	newrec->remoteport.port_state = FC_OBJSTATE_ONLINE;
+	newrec->remoteport.port_num = idx;
+	__nvme_fc_set_dev_loss_tmo(newrec, pinfo);
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	list_add_tail(&newrec->endp_list, &lport->endp_list);
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	nvme_fc_signal_discovery_scan(lport, newrec);
+
+	*portptr = &newrec->remoteport;
+	return 0;
+
+out_kfree_rport:
+	kfree(newrec);
+out_lport_put:
+	nvme_fc_lport_put(lport);
+out_reghost_failed:
+	*portptr = NULL;
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_register_remoteport);
+
+static int
+nvme_fc_abort_lsops(struct nvme_fc_rport *rport)
+{
+	struct nvmefc_ls_req_op *lsop;
+	unsigned long flags;
+
+restart:
+	spin_lock_irqsave(&rport->lock, flags);
+
+	list_for_each_entry(lsop, &rport->ls_req_list, lsreq_list) {
+		if (!(lsop->flags & FCOP_FLAGS_TERMIO)) {
+			lsop->flags |= FCOP_FLAGS_TERMIO;
+			spin_unlock_irqrestore(&rport->lock, flags);
+			rport->lport->ops->ls_abort(&rport->lport->localport,
+						&rport->remoteport,
+						&lsop->ls_req);
+			goto restart;
+		}
+	}
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	return 0;
+}
+
+static void
+nvme_fc_ctrl_connectivity_loss(struct nvme_fc_ctrl *ctrl)
+{
+	dev_info(ctrl->ctrl.device,
+		"NVME-FC{%d}: controller connectivity lost. Awaiting "
+		"Reconnect", ctrl->cnum);
+
+	switch (ctrl->ctrl.state) {
+	case NVME_CTRL_NEW:
+	case NVME_CTRL_LIVE:
+		/*
+		 * Schedule a controller reset. The reset will terminate the
+		 * association and schedule the reconnect timer.  Reconnects
+		 * will be attempted until either the ctlr_loss_tmo
+		 * (max_retries * connect_delay) expires or the remoteport's
+		 * dev_loss_tmo expires.
+		 */
+		if (nvme_reset_ctrl(&ctrl->ctrl)) {
+			dev_warn(ctrl->ctrl.device,
+				"NVME-FC{%d}: Couldn't schedule reset.\n",
+				ctrl->cnum);
+			nvme_delete_ctrl(&ctrl->ctrl);
+		}
+		break;
+
+	case NVME_CTRL_CONNECTING:
+		/*
+		 * The association has already been terminated and the
+		 * controller is attempting reconnects.  No need to do anything
+		 * futher.  Reconnects will be attempted until either the
+		 * ctlr_loss_tmo (max_retries * connect_delay) expires or the
+		 * remoteport's dev_loss_tmo expires.
+		 */
+		break;
+
+	case NVME_CTRL_RESETTING:
+		/*
+		 * Controller is already in the process of terminating the
+		 * association.  No need to do anything further. The reconnect
+		 * step will kick in naturally after the association is
+		 * terminated.
+		 */
+		break;
+
+	case NVME_CTRL_DELETING:
+	default:
+		/* no action to take - let it delete */
+		break;
+	}
+}
+
+/**
+ * nvme_fc_unregister_remoteport - transport entry point called by an
+ *                              LLDD to deregister/remove a previously
+ *                              registered a NVME subsystem FC port.
+ * @remoteport: pointer to the (registered) remote port that is to be
+ *              deregistered.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *portptr)
+{
+	struct nvme_fc_rport *rport = remoteport_to_rport(portptr);
+	struct nvme_fc_ctrl *ctrl;
+	unsigned long flags;
+
+	if (!portptr)
+		return -EINVAL;
+
+	spin_lock_irqsave(&rport->lock, flags);
+
+	if (portptr->port_state != FC_OBJSTATE_ONLINE) {
+		spin_unlock_irqrestore(&rport->lock, flags);
+		return -EINVAL;
+	}
+	portptr->port_state = FC_OBJSTATE_DELETED;
+
+	rport->dev_loss_end = jiffies + (portptr->dev_loss_tmo * HZ);
+
+	list_for_each_entry(ctrl, &rport->ctrl_list, ctrl_list) {
+		/* if dev_loss_tmo==0, dev loss is immediate */
+		if (!portptr->dev_loss_tmo) {
+			dev_warn(ctrl->ctrl.device,
+				"NVME-FC{%d}: controller connectivity lost.\n",
+				ctrl->cnum);
+			nvme_delete_ctrl(&ctrl->ctrl);
+		} else
+			nvme_fc_ctrl_connectivity_loss(ctrl);
+	}
+
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	nvme_fc_abort_lsops(rport);
+
+	if (atomic_read(&rport->act_ctrl_cnt) == 0)
+		rport->lport->ops->remoteport_delete(portptr);
+
+	/*
+	 * release the reference, which will allow, if all controllers
+	 * go away, which should only occur after dev_loss_tmo occurs,
+	 * for the rport to be torn down.
+	 */
+	nvme_fc_rport_put(rport);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_unregister_remoteport);
+
+/**
+ * nvme_fc_rescan_remoteport - transport entry point called by an
+ *                              LLDD to request a nvme device rescan.
+ * @remoteport: pointer to the (registered) remote port that is to be
+ *              rescanned.
+ *
+ * Returns: N/A
+ */
+void
+nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport)
+{
+	struct nvme_fc_rport *rport = remoteport_to_rport(remoteport);
+
+	nvme_fc_signal_discovery_scan(rport->lport, rport);
+}
+EXPORT_SYMBOL_GPL(nvme_fc_rescan_remoteport);
+
+int
+nvme_fc_set_remoteport_devloss(struct nvme_fc_remote_port *portptr,
+			u32 dev_loss_tmo)
+{
+	struct nvme_fc_rport *rport = remoteport_to_rport(portptr);
+	unsigned long flags;
+
+	spin_lock_irqsave(&rport->lock, flags);
+
+	if (portptr->port_state != FC_OBJSTATE_ONLINE) {
+		spin_unlock_irqrestore(&rport->lock, flags);
+		return -EINVAL;
+	}
+
+	/* a dev_loss_tmo of 0 (immediate) is allowed to be set */
+	rport->remoteport.dev_loss_tmo = dev_loss_tmo;
+
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_set_remoteport_devloss);
+
+
+/* *********************** FC-NVME DMA Handling **************************** */
+
+/*
+ * The fcloop device passes in a NULL device pointer. Real LLD's will
+ * pass in a valid device pointer. If NULL is passed to the dma mapping
+ * routines, depending on the platform, it may or may not succeed, and
+ * may crash.
+ *
+ * As such:
+ * Wrapper all the dma routines and check the dev pointer.
+ *
+ * If simple mappings (return just a dma address, we'll noop them,
+ * returning a dma address of 0.
+ *
+ * On more complex mappings (dma_map_sg), a pseudo routine fills
+ * in the scatter list, setting all dma addresses to 0.
+ */
+
+static inline dma_addr_t
+fc_dma_map_single(struct device *dev, void *ptr, size_t size,
+		enum dma_data_direction dir)
+{
+	return dev ? dma_map_single(dev, ptr, size, dir) : (dma_addr_t)0L;
+}
+
+static inline int
+fc_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return dev ? dma_mapping_error(dev, dma_addr) : 0;
+}
+
+static inline void
+fc_dma_unmap_single(struct device *dev, dma_addr_t addr, size_t size,
+	enum dma_data_direction dir)
+{
+	if (dev)
+		dma_unmap_single(dev, addr, size, dir);
+}
+
+static inline void
+fc_dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
+		enum dma_data_direction dir)
+{
+	if (dev)
+		dma_sync_single_for_cpu(dev, addr, size, dir);
+}
+
+static inline void
+fc_dma_sync_single_for_device(struct device *dev, dma_addr_t addr, size_t size,
+		enum dma_data_direction dir)
+{
+	if (dev)
+		dma_sync_single_for_device(dev, addr, size, dir);
+}
+
+/* pseudo dma_map_sg call */
+static int
+fc_map_sg(struct scatterlist *sg, int nents)
+{
+	struct scatterlist *s;
+	int i;
+
+	WARN_ON(nents == 0 || sg[0].length == 0);
+
+	for_each_sg(sg, s, nents, i) {
+		s->dma_address = 0L;
+#ifdef CONFIG_NEED_SG_DMA_LENGTH
+		s->dma_length = s->length;
+#endif
+	}
+	return nents;
+}
+
+static inline int
+fc_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+		enum dma_data_direction dir)
+{
+	return dev ? dma_map_sg(dev, sg, nents, dir) : fc_map_sg(sg, nents);
+}
+
+static inline void
+fc_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+		enum dma_data_direction dir)
+{
+	if (dev)
+		dma_unmap_sg(dev, sg, nents, dir);
+}
+
+/* *********************** FC-NVME LS Handling **************************** */
+
+static void nvme_fc_ctrl_put(struct nvme_fc_ctrl *);
+static int nvme_fc_ctrl_get(struct nvme_fc_ctrl *);
+
+
+static void
+__nvme_fc_finish_ls_req(struct nvmefc_ls_req_op *lsop)
+{
+	struct nvme_fc_rport *rport = lsop->rport;
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rport->lock, flags);
+
+	if (!lsop->req_queued) {
+		spin_unlock_irqrestore(&rport->lock, flags);
+		return;
+	}
+
+	list_del(&lsop->lsreq_list);
+
+	lsop->req_queued = false;
+
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	fc_dma_unmap_single(rport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+
+	nvme_fc_rport_put(rport);
+}
+
+static int
+__nvme_fc_send_ls_req(struct nvme_fc_rport *rport,
+		struct nvmefc_ls_req_op *lsop,
+		void (*done)(struct nvmefc_ls_req *req, int status))
+{
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	unsigned long flags;
+	int ret = 0;
+
+	if (rport->remoteport.port_state != FC_OBJSTATE_ONLINE)
+		return -ECONNREFUSED;
+
+	if (!nvme_fc_rport_get(rport))
+		return -ESHUTDOWN;
+
+	lsreq->done = done;
+	lsop->rport = rport;
+	lsop->req_queued = false;
+	INIT_LIST_HEAD(&lsop->lsreq_list);
+	init_completion(&lsop->ls_done);
+
+	lsreq->rqstdma = fc_dma_map_single(rport->dev, lsreq->rqstaddr,
+				  lsreq->rqstlen + lsreq->rsplen,
+				  DMA_BIDIRECTIONAL);
+	if (fc_dma_mapping_error(rport->dev, lsreq->rqstdma)) {
+		ret = -EFAULT;
+		goto out_putrport;
+	}
+	lsreq->rspdma = lsreq->rqstdma + lsreq->rqstlen;
+
+	spin_lock_irqsave(&rport->lock, flags);
+
+	list_add_tail(&lsop->lsreq_list, &rport->ls_req_list);
+
+	lsop->req_queued = true;
+
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	ret = rport->lport->ops->ls_req(&rport->lport->localport,
+					&rport->remoteport, lsreq);
+	if (ret)
+		goto out_unlink;
+
+	return 0;
+
+out_unlink:
+	lsop->ls_error = ret;
+	spin_lock_irqsave(&rport->lock, flags);
+	lsop->req_queued = false;
+	list_del(&lsop->lsreq_list);
+	spin_unlock_irqrestore(&rport->lock, flags);
+	fc_dma_unmap_single(rport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+out_putrport:
+	nvme_fc_rport_put(rport);
+
+	return ret;
+}
+
+static void
+nvme_fc_send_ls_req_done(struct nvmefc_ls_req *lsreq, int status)
+{
+	struct nvmefc_ls_req_op *lsop = ls_req_to_lsop(lsreq);
+
+	lsop->ls_error = status;
+	complete(&lsop->ls_done);
+}
+
+static int
+nvme_fc_send_ls_req(struct nvme_fc_rport *rport, struct nvmefc_ls_req_op *lsop)
+{
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	struct fcnvme_ls_rjt *rjt = lsreq->rspaddr;
+	int ret;
+
+	ret = __nvme_fc_send_ls_req(rport, lsop, nvme_fc_send_ls_req_done);
+
+	if (!ret) {
+		/*
+		 * No timeout/not interruptible as we need the struct
+		 * to exist until the lldd calls us back. Thus mandate
+		 * wait until driver calls back. lldd responsible for
+		 * the timeout action
+		 */
+		wait_for_completion(&lsop->ls_done);
+
+		__nvme_fc_finish_ls_req(lsop);
+
+		ret = lsop->ls_error;
+	}
+
+	if (ret)
+		return ret;
+
+	/* ACC or RJT payload ? */
+	if (rjt->w0.ls_cmd == FCNVME_LS_RJT)
+		return -ENXIO;
+
+	return 0;
+}
+
+static int
+nvme_fc_send_ls_req_async(struct nvme_fc_rport *rport,
+		struct nvmefc_ls_req_op *lsop,
+		void (*done)(struct nvmefc_ls_req *req, int status))
+{
+	/* don't wait for completion */
+
+	return __nvme_fc_send_ls_req(rport, lsop, done);
+}
+
+/* Validation Error indexes into the string table below */
+enum {
+	VERR_NO_ERROR		= 0,
+	VERR_LSACC		= 1,
+	VERR_LSDESC_RQST	= 2,
+	VERR_LSDESC_RQST_LEN	= 3,
+	VERR_ASSOC_ID		= 4,
+	VERR_ASSOC_ID_LEN	= 5,
+	VERR_CONN_ID		= 6,
+	VERR_CONN_ID_LEN	= 7,
+	VERR_CR_ASSOC		= 8,
+	VERR_CR_ASSOC_ACC_LEN	= 9,
+	VERR_CR_CONN		= 10,
+	VERR_CR_CONN_ACC_LEN	= 11,
+	VERR_DISCONN		= 12,
+	VERR_DISCONN_ACC_LEN	= 13,
+};
+
+static char *validation_errors[] = {
+	"OK",
+	"Not LS_ACC",
+	"Not LSDESC_RQST",
+	"Bad LSDESC_RQST Length",
+	"Not Association ID",
+	"Bad Association ID Length",
+	"Not Connection ID",
+	"Bad Connection ID Length",
+	"Not CR_ASSOC Rqst",
+	"Bad CR_ASSOC ACC Length",
+	"Not CR_CONN Rqst",
+	"Bad CR_CONN ACC Length",
+	"Not Disconnect Rqst",
+	"Bad Disconnect ACC Length",
+};
+
+static int
+nvme_fc_connect_admin_queue(struct nvme_fc_ctrl *ctrl,
+	struct nvme_fc_queue *queue, u16 qsize, u16 ersp_ratio)
+{
+	struct nvmefc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	struct fcnvme_ls_cr_assoc_rqst *assoc_rqst;
+	struct fcnvme_ls_cr_assoc_acc *assoc_acc;
+	int ret, fcret = 0;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			 ctrl->lport->ops->lsrqst_priv_sz +
+			 sizeof(*assoc_rqst) + sizeof(*assoc_acc)), GFP_KERNEL);
+	if (!lsop) {
+		ret = -ENOMEM;
+		goto out_no_memory;
+	}
+	lsreq = &lsop->ls_req;
+
+	lsreq->private = (void *)&lsop[1];
+	assoc_rqst = (struct fcnvme_ls_cr_assoc_rqst *)
+			(lsreq->private + ctrl->lport->ops->lsrqst_priv_sz);
+	assoc_acc = (struct fcnvme_ls_cr_assoc_acc *)&assoc_rqst[1];
+
+	assoc_rqst->w0.ls_cmd = FCNVME_LS_CREATE_ASSOCIATION;
+	assoc_rqst->desc_list_len =
+			cpu_to_be32(sizeof(struct fcnvme_lsdesc_cr_assoc_cmd));
+
+	assoc_rqst->assoc_cmd.desc_tag =
+			cpu_to_be32(FCNVME_LSDESC_CREATE_ASSOC_CMD);
+	assoc_rqst->assoc_cmd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_cr_assoc_cmd));
+
+	assoc_rqst->assoc_cmd.ersp_ratio = cpu_to_be16(ersp_ratio);
+	assoc_rqst->assoc_cmd.sqsize = cpu_to_be16(qsize - 1);
+	/* Linux supports only Dynamic controllers */
+	assoc_rqst->assoc_cmd.cntlid = cpu_to_be16(0xffff);
+	uuid_copy(&assoc_rqst->assoc_cmd.hostid, &ctrl->ctrl.opts->host->id);
+	strncpy(assoc_rqst->assoc_cmd.hostnqn, ctrl->ctrl.opts->host->nqn,
+		min(FCNVME_ASSOC_HOSTNQN_LEN, NVMF_NQN_SIZE));
+	strncpy(assoc_rqst->assoc_cmd.subnqn, ctrl->ctrl.opts->subsysnqn,
+		min(FCNVME_ASSOC_SUBNQN_LEN, NVMF_NQN_SIZE));
+
+	lsop->queue = queue;
+	lsreq->rqstaddr = assoc_rqst;
+	lsreq->rqstlen = sizeof(*assoc_rqst);
+	lsreq->rspaddr = assoc_acc;
+	lsreq->rsplen = sizeof(*assoc_acc);
+	lsreq->timeout = NVME_FC_CONNECT_TIMEOUT_SEC;
+
+	ret = nvme_fc_send_ls_req(ctrl->rport, lsop);
+	if (ret)
+		goto out_free_buffer;
+
+	/* process connect LS completion */
+
+	/* validate the ACC response */
+	if (assoc_acc->hdr.w0.ls_cmd != FCNVME_LS_ACC)
+		fcret = VERR_LSACC;
+	else if (assoc_acc->hdr.desc_list_len !=
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_ls_cr_assoc_acc)))
+		fcret = VERR_CR_ASSOC_ACC_LEN;
+	else if (assoc_acc->hdr.rqst.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_RQST))
+		fcret = VERR_LSDESC_RQST;
+	else if (assoc_acc->hdr.rqst.desc_len !=
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_lsdesc_rqst)))
+		fcret = VERR_LSDESC_RQST_LEN;
+	else if (assoc_acc->hdr.rqst.w0.ls_cmd != FCNVME_LS_CREATE_ASSOCIATION)
+		fcret = VERR_CR_ASSOC;
+	else if (assoc_acc->associd.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_ASSOC_ID))
+		fcret = VERR_ASSOC_ID;
+	else if (assoc_acc->associd.desc_len !=
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_assoc_id)))
+		fcret = VERR_ASSOC_ID_LEN;
+	else if (assoc_acc->connectid.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_CONN_ID))
+		fcret = VERR_CONN_ID;
+	else if (assoc_acc->connectid.desc_len !=
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_lsdesc_conn_id)))
+		fcret = VERR_CONN_ID_LEN;
+
+	if (fcret) {
+		ret = -EBADF;
+		dev_err(ctrl->dev,
+			"q %d connect failed: %s\n",
+			queue->qnum, validation_errors[fcret]);
+	} else {
+		ctrl->association_id =
+			be64_to_cpu(assoc_acc->associd.association_id);
+		queue->connection_id =
+			be64_to_cpu(assoc_acc->connectid.connection_id);
+		set_bit(NVME_FC_Q_CONNECTED, &queue->flags);
+	}
+
+out_free_buffer:
+	kfree(lsop);
+out_no_memory:
+	if (ret)
+		dev_err(ctrl->dev,
+			"queue %d connect admin queue failed (%d).\n",
+			queue->qnum, ret);
+	return ret;
+}
+
+static int
+nvme_fc_connect_queue(struct nvme_fc_ctrl *ctrl, struct nvme_fc_queue *queue,
+			u16 qsize, u16 ersp_ratio)
+{
+	struct nvmefc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	struct fcnvme_ls_cr_conn_rqst *conn_rqst;
+	struct fcnvme_ls_cr_conn_acc *conn_acc;
+	int ret, fcret = 0;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			 ctrl->lport->ops->lsrqst_priv_sz +
+			 sizeof(*conn_rqst) + sizeof(*conn_acc)), GFP_KERNEL);
+	if (!lsop) {
+		ret = -ENOMEM;
+		goto out_no_memory;
+	}
+	lsreq = &lsop->ls_req;
+
+	lsreq->private = (void *)&lsop[1];
+	conn_rqst = (struct fcnvme_ls_cr_conn_rqst *)
+			(lsreq->private + ctrl->lport->ops->lsrqst_priv_sz);
+	conn_acc = (struct fcnvme_ls_cr_conn_acc *)&conn_rqst[1];
+
+	conn_rqst->w0.ls_cmd = FCNVME_LS_CREATE_CONNECTION;
+	conn_rqst->desc_list_len = cpu_to_be32(
+				sizeof(struct fcnvme_lsdesc_assoc_id) +
+				sizeof(struct fcnvme_lsdesc_cr_conn_cmd));
+
+	conn_rqst->associd.desc_tag = cpu_to_be32(FCNVME_LSDESC_ASSOC_ID);
+	conn_rqst->associd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_assoc_id));
+	conn_rqst->associd.association_id = cpu_to_be64(ctrl->association_id);
+	conn_rqst->connect_cmd.desc_tag =
+			cpu_to_be32(FCNVME_LSDESC_CREATE_CONN_CMD);
+	conn_rqst->connect_cmd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_cr_conn_cmd));
+	conn_rqst->connect_cmd.ersp_ratio = cpu_to_be16(ersp_ratio);
+	conn_rqst->connect_cmd.qid  = cpu_to_be16(queue->qnum);
+	conn_rqst->connect_cmd.sqsize = cpu_to_be16(qsize - 1);
+
+	lsop->queue = queue;
+	lsreq->rqstaddr = conn_rqst;
+	lsreq->rqstlen = sizeof(*conn_rqst);
+	lsreq->rspaddr = conn_acc;
+	lsreq->rsplen = sizeof(*conn_acc);
+	lsreq->timeout = NVME_FC_CONNECT_TIMEOUT_SEC;
+
+	ret = nvme_fc_send_ls_req(ctrl->rport, lsop);
+	if (ret)
+		goto out_free_buffer;
+
+	/* process connect LS completion */
+
+	/* validate the ACC response */
+	if (conn_acc->hdr.w0.ls_cmd != FCNVME_LS_ACC)
+		fcret = VERR_LSACC;
+	else if (conn_acc->hdr.desc_list_len !=
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_ls_cr_conn_acc)))
+		fcret = VERR_CR_CONN_ACC_LEN;
+	else if (conn_acc->hdr.rqst.desc_tag != cpu_to_be32(FCNVME_LSDESC_RQST))
+		fcret = VERR_LSDESC_RQST;
+	else if (conn_acc->hdr.rqst.desc_len !=
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_lsdesc_rqst)))
+		fcret = VERR_LSDESC_RQST_LEN;
+	else if (conn_acc->hdr.rqst.w0.ls_cmd != FCNVME_LS_CREATE_CONNECTION)
+		fcret = VERR_CR_CONN;
+	else if (conn_acc->connectid.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_CONN_ID))
+		fcret = VERR_CONN_ID;
+	else if (conn_acc->connectid.desc_len !=
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_lsdesc_conn_id)))
+		fcret = VERR_CONN_ID_LEN;
+
+	if (fcret) {
+		ret = -EBADF;
+		dev_err(ctrl->dev,
+			"q %d connect failed: %s\n",
+			queue->qnum, validation_errors[fcret]);
+	} else {
+		queue->connection_id =
+			be64_to_cpu(conn_acc->connectid.connection_id);
+		set_bit(NVME_FC_Q_CONNECTED, &queue->flags);
+	}
+
+out_free_buffer:
+	kfree(lsop);
+out_no_memory:
+	if (ret)
+		dev_err(ctrl->dev,
+			"queue %d connect command failed (%d).\n",
+			queue->qnum, ret);
+	return ret;
+}
+
+static void
+nvme_fc_disconnect_assoc_done(struct nvmefc_ls_req *lsreq, int status)
+{
+	struct nvmefc_ls_req_op *lsop = ls_req_to_lsop(lsreq);
+
+	__nvme_fc_finish_ls_req(lsop);
+
+	/* fc-nvme iniator doesn't care about success or failure of cmd */
+
+	kfree(lsop);
+}
+
+/*
+ * This routine sends a FC-NVME LS to disconnect (aka terminate)
+ * the FC-NVME Association.  Terminating the association also
+ * terminates the FC-NVME connections (per queue, both admin and io
+ * queues) that are part of the association. E.g. things are torn
+ * down, and the related FC-NVME Association ID and Connection IDs
+ * become invalid.
+ *
+ * The behavior of the fc-nvme initiator is such that it's
+ * understanding of the association and connections will implicitly
+ * be torn down. The action is implicit as it may be due to a loss of
+ * connectivity with the fc-nvme target, so you may never get a
+ * response even if you tried.  As such, the action of this routine
+ * is to asynchronously send the LS, ignore any results of the LS, and
+ * continue on with terminating the association. If the fc-nvme target
+ * is present and receives the LS, it too can tear down.
+ */
+static void
+nvme_fc_xmt_disconnect_assoc(struct nvme_fc_ctrl *ctrl)
+{
+	struct fcnvme_ls_disconnect_rqst *discon_rqst;
+	struct fcnvme_ls_disconnect_acc *discon_acc;
+	struct nvmefc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	int ret;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			 ctrl->lport->ops->lsrqst_priv_sz +
+			 sizeof(*discon_rqst) + sizeof(*discon_acc)),
+			GFP_KERNEL);
+	if (!lsop)
+		/* couldn't sent it... too bad */
+		return;
+
+	lsreq = &lsop->ls_req;
+
+	lsreq->private = (void *)&lsop[1];
+	discon_rqst = (struct fcnvme_ls_disconnect_rqst *)
+			(lsreq->private + ctrl->lport->ops->lsrqst_priv_sz);
+	discon_acc = (struct fcnvme_ls_disconnect_acc *)&discon_rqst[1];
+
+	discon_rqst->w0.ls_cmd = FCNVME_LS_DISCONNECT;
+	discon_rqst->desc_list_len = cpu_to_be32(
+				sizeof(struct fcnvme_lsdesc_assoc_id) +
+				sizeof(struct fcnvme_lsdesc_disconn_cmd));
+
+	discon_rqst->associd.desc_tag = cpu_to_be32(FCNVME_LSDESC_ASSOC_ID);
+	discon_rqst->associd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_assoc_id));
+
+	discon_rqst->associd.association_id = cpu_to_be64(ctrl->association_id);
+
+	discon_rqst->discon_cmd.desc_tag = cpu_to_be32(
+						FCNVME_LSDESC_DISCONN_CMD);
+	discon_rqst->discon_cmd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_disconn_cmd));
+	discon_rqst->discon_cmd.scope = FCNVME_DISCONN_ASSOCIATION;
+	discon_rqst->discon_cmd.id = cpu_to_be64(ctrl->association_id);
+
+	lsreq->rqstaddr = discon_rqst;
+	lsreq->rqstlen = sizeof(*discon_rqst);
+	lsreq->rspaddr = discon_acc;
+	lsreq->rsplen = sizeof(*discon_acc);
+	lsreq->timeout = NVME_FC_CONNECT_TIMEOUT_SEC;
+
+	ret = nvme_fc_send_ls_req_async(ctrl->rport, lsop,
+				nvme_fc_disconnect_assoc_done);
+	if (ret)
+		kfree(lsop);
+
+	/* only meaningful part to terminating the association */
+	ctrl->association_id = 0;
+}
+
+
+/* *********************** NVME Ctrl Routines **************************** */
+
+static void nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg);
+
+static void
+__nvme_fc_exit_request(struct nvme_fc_ctrl *ctrl,
+		struct nvme_fc_fcp_op *op)
+{
+	fc_dma_unmap_single(ctrl->lport->dev, op->fcp_req.rspdma,
+				sizeof(op->rsp_iu), DMA_FROM_DEVICE);
+	fc_dma_unmap_single(ctrl->lport->dev, op->fcp_req.cmddma,
+				sizeof(op->cmd_iu), DMA_TO_DEVICE);
+
+	atomic_set(&op->state, FCPOP_STATE_UNINIT);
+}
+
+static void
+nvme_fc_exit_request(struct blk_mq_tag_set *set, struct request *rq,
+		unsigned int hctx_idx)
+{
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+
+	return __nvme_fc_exit_request(set->driver_data, op);
+}
+
+static int
+__nvme_fc_abort_op(struct nvme_fc_ctrl *ctrl, struct nvme_fc_fcp_op *op)
+{
+	unsigned long flags;
+	int opstate;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	opstate = atomic_xchg(&op->state, FCPOP_STATE_ABORTED);
+	if (opstate != FCPOP_STATE_ACTIVE)
+		atomic_set(&op->state, opstate);
+	else if (ctrl->flags & FCCTRL_TERMIO)
+		ctrl->iocnt++;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+
+	if (opstate != FCPOP_STATE_ACTIVE)
+		return -ECANCELED;
+
+	ctrl->lport->ops->fcp_abort(&ctrl->lport->localport,
+					&ctrl->rport->remoteport,
+					op->queue->lldd_handle,
+					&op->fcp_req);
+
+	return 0;
+}
+
+static void
+nvme_fc_abort_aen_ops(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_fcp_op *aen_op = ctrl->aen_ops;
+	int i;
+
+	/* ensure we've initialized the ops once */
+	if (!(aen_op->flags & FCOP_FLAGS_AEN))
+		return;
+
+	for (i = 0; i < NVME_NR_AEN_COMMANDS; i++, aen_op++)
+		__nvme_fc_abort_op(ctrl, aen_op);
+}
+
+static inline void
+__nvme_fc_fcpop_chk_teardowns(struct nvme_fc_ctrl *ctrl,
+		struct nvme_fc_fcp_op *op, int opstate)
+{
+	unsigned long flags;
+
+	if (opstate == FCPOP_STATE_ABORTED) {
+		spin_lock_irqsave(&ctrl->lock, flags);
+		if (ctrl->flags & FCCTRL_TERMIO) {
+			if (!--ctrl->iocnt)
+				wake_up(&ctrl->ioabort_wait);
+		}
+		spin_unlock_irqrestore(&ctrl->lock, flags);
+	}
+}
+
+static void
+nvme_fc_fcpio_done(struct nvmefc_fcp_req *req)
+{
+	struct nvme_fc_fcp_op *op = fcp_req_to_fcp_op(req);
+	struct request *rq = op->rq;
+	struct nvmefc_fcp_req *freq = &op->fcp_req;
+	struct nvme_fc_ctrl *ctrl = op->ctrl;
+	struct nvme_fc_queue *queue = op->queue;
+	struct nvme_completion *cqe = &op->rsp_iu.cqe;
+	struct nvme_command *sqe = &op->cmd_iu.sqe;
+	__le16 status = cpu_to_le16(NVME_SC_SUCCESS << 1);
+	union nvme_result result;
+	bool terminate_assoc = true;
+	int opstate;
+
+	/*
+	 * WARNING:
+	 * The current linux implementation of a nvme controller
+	 * allocates a single tag set for all io queues and sizes
+	 * the io queues to fully hold all possible tags. Thus, the
+	 * implementation does not reference or care about the sqhd
+	 * value as it never needs to use the sqhd/sqtail pointers
+	 * for submission pacing.
+	 *
+	 * This affects the FC-NVME implementation in two ways:
+	 * 1) As the value doesn't matter, we don't need to waste
+	 *    cycles extracting it from ERSPs and stamping it in the
+	 *    cases where the transport fabricates CQEs on successful
+	 *    completions.
+	 * 2) The FC-NVME implementation requires that delivery of
+	 *    ERSP completions are to go back to the nvme layer in order
+	 *    relative to the rsn, such that the sqhd value will always
+	 *    be "in order" for the nvme layer. As the nvme layer in
+	 *    linux doesn't care about sqhd, there's no need to return
+	 *    them in order.
+	 *
+	 * Additionally:
+	 * As the core nvme layer in linux currently does not look at
+	 * every field in the cqe - in cases where the FC transport must
+	 * fabricate a CQE, the following fields will not be set as they
+	 * are not referenced:
+	 *      cqe.sqid,  cqe.sqhd,  cqe.command_id
+	 *
+	 * Failure or error of an individual i/o, in a transport
+	 * detected fashion unrelated to the nvme completion status,
+	 * potentially cause the initiator and target sides to get out
+	 * of sync on SQ head/tail (aka outstanding io count allowed).
+	 * Per FC-NVME spec, failure of an individual command requires
+	 * the connection to be terminated, which in turn requires the
+	 * association to be terminated.
+	 */
+
+	opstate = atomic_xchg(&op->state, FCPOP_STATE_COMPLETE);
+
+	fc_dma_sync_single_for_cpu(ctrl->lport->dev, op->fcp_req.rspdma,
+				sizeof(op->rsp_iu), DMA_FROM_DEVICE);
+
+	if (opstate == FCPOP_STATE_ABORTED)
+		status = cpu_to_le16(NVME_SC_ABORT_REQ << 1);
+	else if (freq->status)
+		status = cpu_to_le16(NVME_SC_INTERNAL << 1);
+
+	/*
+	 * For the linux implementation, if we have an unsuccesful
+	 * status, they blk-mq layer can typically be called with the
+	 * non-zero status and the content of the cqe isn't important.
+	 */
+	if (status)
+		goto done;
+
+	/*
+	 * command completed successfully relative to the wire
+	 * protocol. However, validate anything received and
+	 * extract the status and result from the cqe (create it
+	 * where necessary).
+	 */
+
+	switch (freq->rcv_rsplen) {
+
+	case 0:
+	case NVME_FC_SIZEOF_ZEROS_RSP:
+		/*
+		 * No response payload or 12 bytes of payload (which
+		 * should all be zeros) are considered successful and
+		 * no payload in the CQE by the transport.
+		 */
+		if (freq->transferred_length !=
+			be32_to_cpu(op->cmd_iu.data_len)) {
+			status = cpu_to_le16(NVME_SC_INTERNAL << 1);
+			goto done;
+		}
+		result.u64 = 0;
+		break;
+
+	case sizeof(struct nvme_fc_ersp_iu):
+		/*
+		 * The ERSP IU contains a full completion with CQE.
+		 * Validate ERSP IU and look at cqe.
+		 */
+		if (unlikely(be16_to_cpu(op->rsp_iu.iu_len) !=
+					(freq->rcv_rsplen / 4) ||
+			     be32_to_cpu(op->rsp_iu.xfrd_len) !=
+					freq->transferred_length ||
+			     op->rsp_iu.status_code ||
+			     sqe->common.command_id != cqe->command_id)) {
+			status = cpu_to_le16(NVME_SC_INTERNAL << 1);
+			goto done;
+		}
+		result = cqe->result;
+		status = cqe->status;
+		break;
+
+	default:
+		status = cpu_to_le16(NVME_SC_INTERNAL << 1);
+		goto done;
+	}
+
+	terminate_assoc = false;
+
+done:
+	if (op->flags & FCOP_FLAGS_AEN) {
+		nvme_complete_async_event(&queue->ctrl->ctrl, status, &result);
+		__nvme_fc_fcpop_chk_teardowns(ctrl, op, opstate);
+		atomic_set(&op->state, FCPOP_STATE_IDLE);
+		op->flags = FCOP_FLAGS_AEN;	/* clear other flags */
+		nvme_fc_ctrl_put(ctrl);
+		goto check_error;
+	}
+
+	__nvme_fc_fcpop_chk_teardowns(ctrl, op, opstate);
+	nvme_end_request(rq, status, result);
+
+check_error:
+	if (terminate_assoc)
+		nvme_fc_error_recovery(ctrl, "transport detected io error");
+}
+
+static int
+__nvme_fc_init_request(struct nvme_fc_ctrl *ctrl,
+		struct nvme_fc_queue *queue, struct nvme_fc_fcp_op *op,
+		struct request *rq, u32 rqno)
+{
+	struct nvme_fc_cmd_iu *cmdiu = &op->cmd_iu;
+	int ret = 0;
+
+	memset(op, 0, sizeof(*op));
+	op->fcp_req.cmdaddr = &op->cmd_iu;
+	op->fcp_req.cmdlen = sizeof(op->cmd_iu);
+	op->fcp_req.rspaddr = &op->rsp_iu;
+	op->fcp_req.rsplen = sizeof(op->rsp_iu);
+	op->fcp_req.done = nvme_fc_fcpio_done;
+	op->fcp_req.first_sgl = (struct scatterlist *)&op[1];
+	op->fcp_req.private = &op->fcp_req.first_sgl[SG_CHUNK_SIZE];
+	op->ctrl = ctrl;
+	op->queue = queue;
+	op->rq = rq;
+	op->rqno = rqno;
+
+	cmdiu->scsi_id = NVME_CMD_SCSI_ID;
+	cmdiu->fc_id = NVME_CMD_FC_ID;
+	cmdiu->iu_len = cpu_to_be16(sizeof(*cmdiu) / sizeof(u32));
+
+	op->fcp_req.cmddma = fc_dma_map_single(ctrl->lport->dev,
+				&op->cmd_iu, sizeof(op->cmd_iu), DMA_TO_DEVICE);
+	if (fc_dma_mapping_error(ctrl->lport->dev, op->fcp_req.cmddma)) {
+		dev_err(ctrl->dev,
+			"FCP Op failed - cmdiu dma mapping failed.\n");
+		ret = -EFAULT;
+		goto out_on_error;
+	}
+
+	op->fcp_req.rspdma = fc_dma_map_single(ctrl->lport->dev,
+				&op->rsp_iu, sizeof(op->rsp_iu),
+				DMA_FROM_DEVICE);
+	if (fc_dma_mapping_error(ctrl->lport->dev, op->fcp_req.rspdma)) {
+		dev_err(ctrl->dev,
+			"FCP Op failed - rspiu dma mapping failed.\n");
+		ret = -EFAULT;
+	}
+
+	atomic_set(&op->state, FCPOP_STATE_IDLE);
+out_on_error:
+	return ret;
+}
+
+static int
+nvme_fc_init_request(struct blk_mq_tag_set *set, struct request *rq,
+		unsigned int hctx_idx, unsigned int numa_node)
+{
+	struct nvme_fc_ctrl *ctrl = set->driver_data;
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+	int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
+	struct nvme_fc_queue *queue = &ctrl->queues[queue_idx];
+
+	nvme_req(rq)->ctrl = &ctrl->ctrl;
+	return __nvme_fc_init_request(ctrl, queue, op, rq, queue->rqcnt++);
+}
+
+static int
+nvme_fc_init_aen_ops(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_fcp_op *aen_op;
+	struct nvme_fc_cmd_iu *cmdiu;
+	struct nvme_command *sqe;
+	void *private;
+	int i, ret;
+
+	aen_op = ctrl->aen_ops;
+	for (i = 0; i < NVME_NR_AEN_COMMANDS; i++, aen_op++) {
+		private = kzalloc(ctrl->lport->ops->fcprqst_priv_sz,
+						GFP_KERNEL);
+		if (!private)
+			return -ENOMEM;
+
+		cmdiu = &aen_op->cmd_iu;
+		sqe = &cmdiu->sqe;
+		ret = __nvme_fc_init_request(ctrl, &ctrl->queues[0],
+				aen_op, (struct request *)NULL,
+				(NVME_AQ_BLK_MQ_DEPTH + i));
+		if (ret) {
+			kfree(private);
+			return ret;
+		}
+
+		aen_op->flags = FCOP_FLAGS_AEN;
+		aen_op->fcp_req.first_sgl = NULL; /* no sg list */
+		aen_op->fcp_req.private = private;
+
+		memset(sqe, 0, sizeof(*sqe));
+		sqe->common.opcode = nvme_admin_async_event;
+		/* Note: core layer may overwrite the sqe.command_id value */
+		sqe->common.command_id = NVME_AQ_BLK_MQ_DEPTH + i;
+	}
+	return 0;
+}
+
+static void
+nvme_fc_term_aen_ops(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_fcp_op *aen_op;
+	int i;
+
+	cancel_work_sync(&ctrl->ctrl.async_event_work);
+	aen_op = ctrl->aen_ops;
+	for (i = 0; i < NVME_NR_AEN_COMMANDS; i++, aen_op++) {
+		if (!aen_op->fcp_req.private)
+			continue;
+
+		__nvme_fc_exit_request(ctrl, aen_op);
+
+		kfree(aen_op->fcp_req.private);
+		aen_op->fcp_req.private = NULL;
+	}
+}
+
+static inline void
+__nvme_fc_init_hctx(struct blk_mq_hw_ctx *hctx, struct nvme_fc_ctrl *ctrl,
+		unsigned int qidx)
+{
+	struct nvme_fc_queue *queue = &ctrl->queues[qidx];
+
+	hctx->driver_data = queue;
+	queue->hctx = hctx;
+}
+
+static int
+nvme_fc_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_fc_ctrl *ctrl = data;
+
+	__nvme_fc_init_hctx(hctx, ctrl, hctx_idx + 1);
+
+	return 0;
+}
+
+static int
+nvme_fc_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_fc_ctrl *ctrl = data;
+
+	__nvme_fc_init_hctx(hctx, ctrl, hctx_idx);
+
+	return 0;
+}
+
+static void
+nvme_fc_init_queue(struct nvme_fc_ctrl *ctrl, int idx)
+{
+	struct nvme_fc_queue *queue;
+
+	queue = &ctrl->queues[idx];
+	memset(queue, 0, sizeof(*queue));
+	queue->ctrl = ctrl;
+	queue->qnum = idx;
+	atomic_set(&queue->csn, 0);
+	queue->dev = ctrl->dev;
+
+	if (idx > 0)
+		queue->cmnd_capsule_len = ctrl->ctrl.ioccsz * 16;
+	else
+		queue->cmnd_capsule_len = sizeof(struct nvme_command);
+
+	/*
+	 * Considered whether we should allocate buffers for all SQEs
+	 * and CQEs and dma map them - mapping their respective entries
+	 * into the request structures (kernel vm addr and dma address)
+	 * thus the driver could use the buffers/mappings directly.
+	 * It only makes sense if the LLDD would use them for its
+	 * messaging api. It's very unlikely most adapter api's would use
+	 * a native NVME sqe/cqe. More reasonable if FC-NVME IU payload
+	 * structures were used instead.
+	 */
+}
+
+/*
+ * This routine terminates a queue at the transport level.
+ * The transport has already ensured that all outstanding ios on
+ * the queue have been terminated.
+ * The transport will send a Disconnect LS request to terminate
+ * the queue's connection. Termination of the admin queue will also
+ * terminate the association at the target.
+ */
+static void
+nvme_fc_free_queue(struct nvme_fc_queue *queue)
+{
+	if (!test_and_clear_bit(NVME_FC_Q_CONNECTED, &queue->flags))
+		return;
+
+	clear_bit(NVME_FC_Q_LIVE, &queue->flags);
+	/*
+	 * Current implementation never disconnects a single queue.
+	 * It always terminates a whole association. So there is never
+	 * a disconnect(queue) LS sent to the target.
+	 */
+
+	queue->connection_id = 0;
+	atomic_set(&queue->csn, 0);
+}
+
+static void
+__nvme_fc_delete_hw_queue(struct nvme_fc_ctrl *ctrl,
+	struct nvme_fc_queue *queue, unsigned int qidx)
+{
+	if (ctrl->lport->ops->delete_queue)
+		ctrl->lport->ops->delete_queue(&ctrl->lport->localport, qidx,
+				queue->lldd_handle);
+	queue->lldd_handle = NULL;
+}
+
+static void
+nvme_fc_free_io_queues(struct nvme_fc_ctrl *ctrl)
+{
+	int i;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++)
+		nvme_fc_free_queue(&ctrl->queues[i]);
+}
+
+static int
+__nvme_fc_create_hw_queue(struct nvme_fc_ctrl *ctrl,
+	struct nvme_fc_queue *queue, unsigned int qidx, u16 qsize)
+{
+	int ret = 0;
+
+	queue->lldd_handle = NULL;
+	if (ctrl->lport->ops->create_queue)
+		ret = ctrl->lport->ops->create_queue(&ctrl->lport->localport,
+				qidx, qsize, &queue->lldd_handle);
+
+	return ret;
+}
+
+static void
+nvme_fc_delete_hw_io_queues(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_queue *queue = &ctrl->queues[ctrl->ctrl.queue_count - 1];
+	int i;
+
+	for (i = ctrl->ctrl.queue_count - 1; i >= 1; i--, queue--)
+		__nvme_fc_delete_hw_queue(ctrl, queue, i);
+}
+
+static int
+nvme_fc_create_hw_io_queues(struct nvme_fc_ctrl *ctrl, u16 qsize)
+{
+	struct nvme_fc_queue *queue = &ctrl->queues[1];
+	int i, ret;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++, queue++) {
+		ret = __nvme_fc_create_hw_queue(ctrl, queue, i, qsize);
+		if (ret)
+			goto delete_queues;
+	}
+
+	return 0;
+
+delete_queues:
+	for (; i >= 0; i--)
+		__nvme_fc_delete_hw_queue(ctrl, &ctrl->queues[i], i);
+	return ret;
+}
+
+static int
+nvme_fc_connect_io_queues(struct nvme_fc_ctrl *ctrl, u16 qsize)
+{
+	int i, ret = 0;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		ret = nvme_fc_connect_queue(ctrl, &ctrl->queues[i], qsize,
+					(qsize / 5));
+		if (ret)
+			break;
+		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
+		if (ret)
+			break;
+
+		set_bit(NVME_FC_Q_LIVE, &ctrl->queues[i].flags);
+	}
+
+	return ret;
+}
+
+static void
+nvme_fc_init_io_queues(struct nvme_fc_ctrl *ctrl)
+{
+	int i;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++)
+		nvme_fc_init_queue(ctrl, i);
+}
+
+static void
+nvme_fc_ctrl_free(struct kref *ref)
+{
+	struct nvme_fc_ctrl *ctrl =
+		container_of(ref, struct nvme_fc_ctrl, ref);
+	unsigned long flags;
+
+	if (ctrl->ctrl.tagset) {
+		blk_cleanup_queue(ctrl->ctrl.connect_q);
+		blk_mq_free_tag_set(&ctrl->tag_set);
+	}
+
+	/* remove from rport list */
+	spin_lock_irqsave(&ctrl->rport->lock, flags);
+	list_del(&ctrl->ctrl_list);
+	spin_unlock_irqrestore(&ctrl->rport->lock, flags);
+
+	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
+	blk_cleanup_queue(ctrl->ctrl.admin_q);
+	blk_mq_free_tag_set(&ctrl->admin_tag_set);
+
+	kfree(ctrl->queues);
+
+	put_device(ctrl->dev);
+	nvme_fc_rport_put(ctrl->rport);
+
+	ida_simple_remove(&nvme_fc_ctrl_cnt, ctrl->cnum);
+	if (ctrl->ctrl.opts)
+		nvmf_free_options(ctrl->ctrl.opts);
+	kfree(ctrl);
+}
+
+static void
+nvme_fc_ctrl_put(struct nvme_fc_ctrl *ctrl)
+{
+	kref_put(&ctrl->ref, nvme_fc_ctrl_free);
+}
+
+static int
+nvme_fc_ctrl_get(struct nvme_fc_ctrl *ctrl)
+{
+	return kref_get_unless_zero(&ctrl->ref);
+}
+
+/*
+ * All accesses from nvme core layer done - can now free the
+ * controller. Called after last nvme_put_ctrl() call
+ */
+static void
+nvme_fc_nvme_ctrl_freed(struct nvme_ctrl *nctrl)
+{
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(nctrl);
+
+	WARN_ON(nctrl != &ctrl->ctrl);
+
+	nvme_fc_ctrl_put(ctrl);
+}
+
+static void
+nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
+{
+	int active;
+
+	/*
+	 * if an error (io timeout, etc) while (re)connecting,
+	 * it's an error on creating the new association.
+	 * Start the error recovery thread if it hasn't already
+	 * been started. It is expected there could be multiple
+	 * ios hitting this path before things are cleaned up.
+	 */
+	if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {
+		active = atomic_xchg(&ctrl->err_work_active, 1);
+		if (!active && !queue_work(nvme_fc_wq, &ctrl->err_work)) {
+			atomic_set(&ctrl->err_work_active, 0);
+			WARN_ON(1);
+		}
+		return;
+	}
+
+	/* Otherwise, only proceed if in LIVE state - e.g. on first error */
+	if (ctrl->ctrl.state != NVME_CTRL_LIVE)
+		return;
+
+	dev_warn(ctrl->ctrl.device,
+		"NVME-FC{%d}: transport association error detected: %s\n",
+		ctrl->cnum, errmsg);
+	dev_warn(ctrl->ctrl.device,
+		"NVME-FC{%d}: resetting controller\n", ctrl->cnum);
+
+	nvme_reset_ctrl(&ctrl->ctrl);
+}
+
+static enum blk_eh_timer_return
+nvme_fc_timeout(struct request *rq, bool reserved)
+{
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+	struct nvme_fc_ctrl *ctrl = op->ctrl;
+
+	/*
+	 * we can't individually ABTS an io without affecting the queue,
+	 * thus killing the queue, and thus the association.
+	 * So resolve by performing a controller reset, which will stop
+	 * the host/io stack, terminate the association on the link,
+	 * and recreate an association on the link.
+	 */
+	nvme_fc_error_recovery(ctrl, "io timeout error");
+
+	/*
+	 * the io abort has been initiated. Have the reset timer
+	 * restarted and the abort completion will complete the io
+	 * shortly. Avoids a synchronous wait while the abort finishes.
+	 */
+	return BLK_EH_RESET_TIMER;
+}
+
+static int
+nvme_fc_map_data(struct nvme_fc_ctrl *ctrl, struct request *rq,
+		struct nvme_fc_fcp_op *op)
+{
+	struct nvmefc_fcp_req *freq = &op->fcp_req;
+	enum dma_data_direction dir;
+	int ret;
+
+	freq->sg_cnt = 0;
+
+	if (!blk_rq_payload_bytes(rq))
+		return 0;
+
+	freq->sg_table.sgl = freq->first_sgl;
+	ret = sg_alloc_table_chained(&freq->sg_table,
+			blk_rq_nr_phys_segments(rq), freq->sg_table.sgl);
+	if (ret)
+		return -ENOMEM;
+
+	op->nents = blk_rq_map_sg(rq->q, rq, freq->sg_table.sgl);
+	WARN_ON(op->nents > blk_rq_nr_phys_segments(rq));
+	dir = (rq_data_dir(rq) == WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+	freq->sg_cnt = fc_dma_map_sg(ctrl->lport->dev, freq->sg_table.sgl,
+				op->nents, dir);
+	if (unlikely(freq->sg_cnt <= 0)) {
+		sg_free_table_chained(&freq->sg_table, true);
+		freq->sg_cnt = 0;
+		return -EFAULT;
+	}
+
+	/*
+	 * TODO: blk_integrity_rq(rq)  for DIF
+	 */
+	return 0;
+}
+
+static void
+nvme_fc_unmap_data(struct nvme_fc_ctrl *ctrl, struct request *rq,
+		struct nvme_fc_fcp_op *op)
+{
+	struct nvmefc_fcp_req *freq = &op->fcp_req;
+
+	if (!freq->sg_cnt)
+		return;
+
+	fc_dma_unmap_sg(ctrl->lport->dev, freq->sg_table.sgl, op->nents,
+				((rq_data_dir(rq) == WRITE) ?
+					DMA_TO_DEVICE : DMA_FROM_DEVICE));
+
+	nvme_cleanup_cmd(rq);
+
+	sg_free_table_chained(&freq->sg_table, true);
+
+	freq->sg_cnt = 0;
+}
+
+/*
+ * In FC, the queue is a logical thing. At transport connect, the target
+ * creates its "queue" and returns a handle that is to be given to the
+ * target whenever it posts something to the corresponding SQ.  When an
+ * SQE is sent on a SQ, FC effectively considers the SQE, or rather the
+ * command contained within the SQE, an io, and assigns a FC exchange
+ * to it. The SQE and the associated SQ handle are sent in the initial
+ * CMD IU sents on the exchange. All transfers relative to the io occur
+ * as part of the exchange.  The CQE is the last thing for the io,
+ * which is transferred (explicitly or implicitly) with the RSP IU
+ * sent on the exchange. After the CQE is received, the FC exchange is
+ * terminaed and the Exchange may be used on a different io.
+ *
+ * The transport to LLDD api has the transport making a request for a
+ * new fcp io request to the LLDD. The LLDD then allocates a FC exchange
+ * resource and transfers the command. The LLDD will then process all
+ * steps to complete the io. Upon completion, the transport done routine
+ * is called.
+ *
+ * So - while the operation is outstanding to the LLDD, there is a link
+ * level FC exchange resource that is also outstanding. This must be
+ * considered in all cleanup operations.
+ */
+static blk_status_t
+nvme_fc_start_fcp_op(struct nvme_fc_ctrl *ctrl, struct nvme_fc_queue *queue,
+	struct nvme_fc_fcp_op *op, u32 data_len,
+	enum nvmefc_fcp_datadir	io_dir)
+{
+	struct nvme_fc_cmd_iu *cmdiu = &op->cmd_iu;
+	struct nvme_command *sqe = &cmdiu->sqe;
+	int ret, opstate;
+
+	/*
+	 * before attempting to send the io, check to see if we believe
+	 * the target device is present
+	 */
+	if (ctrl->rport->remoteport.port_state != FC_OBJSTATE_ONLINE)
+		return BLK_STS_RESOURCE;
+
+	if (!nvme_fc_ctrl_get(ctrl))
+		return BLK_STS_IOERR;
+
+	/* format the FC-NVME CMD IU and fcp_req */
+	cmdiu->connection_id = cpu_to_be64(queue->connection_id);
+	cmdiu->data_len = cpu_to_be32(data_len);
+	switch (io_dir) {
+	case NVMEFC_FCP_WRITE:
+		cmdiu->flags = FCNVME_CMD_FLAGS_WRITE;
+		break;
+	case NVMEFC_FCP_READ:
+		cmdiu->flags = FCNVME_CMD_FLAGS_READ;
+		break;
+	case NVMEFC_FCP_NODATA:
+		cmdiu->flags = 0;
+		break;
+	}
+	op->fcp_req.payload_length = data_len;
+	op->fcp_req.io_dir = io_dir;
+	op->fcp_req.transferred_length = 0;
+	op->fcp_req.rcv_rsplen = 0;
+	op->fcp_req.status = NVME_SC_SUCCESS;
+	op->fcp_req.sqid = cpu_to_le16(queue->qnum);
+
+	/*
+	 * validate per fabric rules, set fields mandated by fabric spec
+	 * as well as those by FC-NVME spec.
+	 */
+	WARN_ON_ONCE(sqe->common.metadata);
+	sqe->common.flags |= NVME_CMD_SGL_METABUF;
+
+	/*
+	 * format SQE DPTR field per FC-NVME rules:
+	 *    type=0x5     Transport SGL Data Block Descriptor
+	 *    subtype=0xA  Transport-specific value
+	 *    address=0
+	 *    length=length of the data series
+	 */
+	sqe->rw.dptr.sgl.type = (NVME_TRANSPORT_SGL_DATA_DESC << 4) |
+					NVME_SGL_FMT_TRANSPORT_A;
+	sqe->rw.dptr.sgl.length = cpu_to_le32(data_len);
+	sqe->rw.dptr.sgl.addr = 0;
+
+	if (!(op->flags & FCOP_FLAGS_AEN)) {
+		ret = nvme_fc_map_data(ctrl, op->rq, op);
+		if (ret < 0) {
+			nvme_cleanup_cmd(op->rq);
+			nvme_fc_ctrl_put(ctrl);
+			if (ret == -ENOMEM || ret == -EAGAIN)
+				return BLK_STS_RESOURCE;
+			return BLK_STS_IOERR;
+		}
+	}
+
+	fc_dma_sync_single_for_device(ctrl->lport->dev, op->fcp_req.cmddma,
+				  sizeof(op->cmd_iu), DMA_TO_DEVICE);
+
+	atomic_set(&op->state, FCPOP_STATE_ACTIVE);
+
+	if (!(op->flags & FCOP_FLAGS_AEN))
+		blk_mq_start_request(op->rq);
+
+	cmdiu->csn = cpu_to_be32(atomic_inc_return(&queue->csn));
+	ret = ctrl->lport->ops->fcp_io(&ctrl->lport->localport,
+					&ctrl->rport->remoteport,
+					queue->lldd_handle, &op->fcp_req);
+
+	if (ret) {
+		/*
+		 * If the lld fails to send the command is there an issue with
+		 * the csn value?  If the command that fails is the Connect,
+		 * no - as the connection won't be live.  If it is a command
+		 * post-connect, it's possible a gap in csn may be created.
+		 * Does this matter?  As Linux initiators don't send fused
+		 * commands, no.  The gap would exist, but as there's nothing
+		 * that depends on csn order to be delivered on the target
+		 * side, it shouldn't hurt.  It would be difficult for a
+		 * target to even detect the csn gap as it has no idea when the
+		 * cmd with the csn was supposed to arrive.
+		 */
+		opstate = atomic_xchg(&op->state, FCPOP_STATE_COMPLETE);
+		__nvme_fc_fcpop_chk_teardowns(ctrl, op, opstate);
+
+		if (!(op->flags & FCOP_FLAGS_AEN))
+			nvme_fc_unmap_data(ctrl, op->rq, op);
+
+		nvme_fc_ctrl_put(ctrl);
+
+		if (ctrl->rport->remoteport.port_state == FC_OBJSTATE_ONLINE &&
+				ret != -EBUSY)
+			return BLK_STS_IOERR;
+
+		return BLK_STS_RESOURCE;
+	}
+
+	return BLK_STS_OK;
+}
+
+static blk_status_t
+nvme_fc_queue_rq(struct blk_mq_hw_ctx *hctx,
+			const struct blk_mq_queue_data *bd)
+{
+	struct nvme_ns *ns = hctx->queue->queuedata;
+	struct nvme_fc_queue *queue = hctx->driver_data;
+	struct nvme_fc_ctrl *ctrl = queue->ctrl;
+	struct request *rq = bd->rq;
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+	struct nvme_fc_cmd_iu *cmdiu = &op->cmd_iu;
+	struct nvme_command *sqe = &cmdiu->sqe;
+	enum nvmefc_fcp_datadir	io_dir;
+	bool queue_ready = test_bit(NVME_FC_Q_LIVE, &queue->flags);
+	u32 data_len;
+	blk_status_t ret;
+
+	if (ctrl->rport->remoteport.port_state != FC_OBJSTATE_ONLINE ||
+	    !nvmf_check_ready(&queue->ctrl->ctrl, rq, queue_ready))
+		return nvmf_fail_nonready_command(&queue->ctrl->ctrl, rq);
+
+	ret = nvme_setup_cmd(ns, rq, sqe);
+	if (ret)
+		return ret;
+
+	data_len = blk_rq_payload_bytes(rq);
+	if (data_len)
+		io_dir = ((rq_data_dir(rq) == WRITE) ?
+					NVMEFC_FCP_WRITE : NVMEFC_FCP_READ);
+	else
+		io_dir = NVMEFC_FCP_NODATA;
+
+	return nvme_fc_start_fcp_op(ctrl, queue, op, data_len, io_dir);
+}
+
+static struct blk_mq_tags *
+nvme_fc_tagset(struct nvme_fc_queue *queue)
+{
+	if (queue->qnum == 0)
+		return queue->ctrl->admin_tag_set.tags[queue->qnum];
+
+	return queue->ctrl->tag_set.tags[queue->qnum - 1];
+}
+
+static int
+nvme_fc_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
+
+{
+	struct nvme_fc_queue *queue = hctx->driver_data;
+	struct nvme_fc_ctrl *ctrl = queue->ctrl;
+	struct request *req;
+	struct nvme_fc_fcp_op *op;
+
+	req = blk_mq_tag_to_rq(nvme_fc_tagset(queue), tag);
+	if (!req)
+		return 0;
+
+	op = blk_mq_rq_to_pdu(req);
+
+	if ((atomic_read(&op->state) == FCPOP_STATE_ACTIVE) &&
+		 (ctrl->lport->ops->poll_queue))
+		ctrl->lport->ops->poll_queue(&ctrl->lport->localport,
+						 queue->lldd_handle);
+
+	return ((atomic_read(&op->state) != FCPOP_STATE_ACTIVE));
+}
+
+static void
+nvme_fc_submit_async_event(struct nvme_ctrl *arg)
+{
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(arg);
+	struct nvme_fc_fcp_op *aen_op;
+	unsigned long flags;
+	bool terminating = false;
+	blk_status_t ret;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	if (ctrl->flags & FCCTRL_TERMIO)
+		terminating = true;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+
+	if (terminating)
+		return;
+
+	aen_op = &ctrl->aen_ops[0];
+
+	ret = nvme_fc_start_fcp_op(ctrl, aen_op->queue, aen_op, 0,
+					NVMEFC_FCP_NODATA);
+	if (ret)
+		dev_err(ctrl->ctrl.device,
+			"failed async event work\n");
+}
+
+static void
+nvme_fc_complete_rq(struct request *rq)
+{
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+	struct nvme_fc_ctrl *ctrl = op->ctrl;
+
+	atomic_set(&op->state, FCPOP_STATE_IDLE);
+
+	nvme_fc_unmap_data(ctrl, rq, op);
+	nvme_complete_rq(rq);
+	nvme_fc_ctrl_put(ctrl);
+}
+
+/*
+ * This routine is used by the transport when it needs to find active
+ * io on a queue that is to be terminated. The transport uses
+ * blk_mq_tagset_busy_itr() to find the busy requests, which then invoke
+ * this routine to kill them on a 1 by 1 basis.
+ *
+ * As FC allocates FC exchange for each io, the transport must contact
+ * the LLDD to terminate the exchange, thus releasing the FC exchange.
+ * After terminating the exchange the LLDD will call the transport's
+ * normal io done path for the request, but it will have an aborted
+ * status. The done path will return the io request back to the block
+ * layer with an error status.
+ */
+static void
+nvme_fc_terminate_exchange(struct request *req, void *data, bool reserved)
+{
+	struct nvme_ctrl *nctrl = data;
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(nctrl);
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(req);
+
+	__nvme_fc_abort_op(ctrl, op);
+}
+
+
+static const struct blk_mq_ops nvme_fc_mq_ops = {
+	.queue_rq	= nvme_fc_queue_rq,
+	.complete	= nvme_fc_complete_rq,
+	.init_request	= nvme_fc_init_request,
+	.exit_request	= nvme_fc_exit_request,
+	.init_hctx	= nvme_fc_init_hctx,
+	.poll		= nvme_fc_poll,
+	.timeout	= nvme_fc_timeout,
+};
+
+static int
+nvme_fc_create_io_queues(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
+	unsigned int nr_io_queues;
+	int ret;
+
+	nr_io_queues = min(min(opts->nr_io_queues, num_online_cpus()),
+				ctrl->lport->ops->max_hw_queues);
+	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
+	if (ret) {
+		dev_info(ctrl->ctrl.device,
+			"set_queue_count failed: %d\n", ret);
+		return ret;
+	}
+
+	ctrl->ctrl.queue_count = nr_io_queues + 1;
+	if (!nr_io_queues)
+		return 0;
+
+	nvme_fc_init_io_queues(ctrl);
+
+	memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set));
+	ctrl->tag_set.ops = &nvme_fc_mq_ops;
+	ctrl->tag_set.queue_depth = ctrl->ctrl.opts->queue_size;
+	ctrl->tag_set.reserved_tags = 1; /* fabric connect */
+	ctrl->tag_set.numa_node = NUMA_NO_NODE;
+	ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+	ctrl->tag_set.cmd_size = sizeof(struct nvme_fc_fcp_op) +
+					(SG_CHUNK_SIZE *
+						sizeof(struct scatterlist)) +
+					ctrl->lport->ops->fcprqst_priv_sz;
+	ctrl->tag_set.driver_data = ctrl;
+	ctrl->tag_set.nr_hw_queues = ctrl->ctrl.queue_count - 1;
+	ctrl->tag_set.timeout = NVME_IO_TIMEOUT;
+
+	ret = blk_mq_alloc_tag_set(&ctrl->tag_set);
+	if (ret)
+		return ret;
+
+	ctrl->ctrl.tagset = &ctrl->tag_set;
+
+	ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
+	if (IS_ERR(ctrl->ctrl.connect_q)) {
+		ret = PTR_ERR(ctrl->ctrl.connect_q);
+		goto out_free_tag_set;
+	}
+
+	ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
+	if (ret)
+		goto out_cleanup_blk_queue;
+
+	ret = nvme_fc_connect_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
+	if (ret)
+		goto out_delete_hw_queues;
+
+	ctrl->ioq_live = true;
+
+	return 0;
+
+out_delete_hw_queues:
+	nvme_fc_delete_hw_io_queues(ctrl);
+out_cleanup_blk_queue:
+	blk_cleanup_queue(ctrl->ctrl.connect_q);
+out_free_tag_set:
+	blk_mq_free_tag_set(&ctrl->tag_set);
+	nvme_fc_free_io_queues(ctrl);
+
+	/* force put free routine to ignore io queues */
+	ctrl->ctrl.tagset = NULL;
+
+	return ret;
+}
+
+static int
+nvme_fc_recreate_io_queues(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
+	unsigned int nr_io_queues;
+	int ret;
+
+	nr_io_queues = min(min(opts->nr_io_queues, num_online_cpus()),
+				ctrl->lport->ops->max_hw_queues);
+	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
+	if (ret) {
+		dev_info(ctrl->ctrl.device,
+			"set_queue_count failed: %d\n", ret);
+		return ret;
+	}
+
+	ctrl->ctrl.queue_count = nr_io_queues + 1;
+	/* check for io queues existing */
+	if (ctrl->ctrl.queue_count == 1)
+		return 0;
+
+	ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
+	if (ret)
+		goto out_free_io_queues;
+
+	ret = nvme_fc_connect_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
+	if (ret)
+		goto out_delete_hw_queues;
+
+	blk_mq_update_nr_hw_queues(&ctrl->tag_set, nr_io_queues);
+
+	return 0;
+
+out_delete_hw_queues:
+	nvme_fc_delete_hw_io_queues(ctrl);
+out_free_io_queues:
+	nvme_fc_free_io_queues(ctrl);
+	return ret;
+}
+
+static void
+nvme_fc_rport_active_on_lport(struct nvme_fc_rport *rport)
+{
+	struct nvme_fc_lport *lport = rport->lport;
+
+	atomic_inc(&lport->act_rport_cnt);
+}
+
+static void
+nvme_fc_rport_inactive_on_lport(struct nvme_fc_rport *rport)
+{
+	struct nvme_fc_lport *lport = rport->lport;
+	u32 cnt;
+
+	cnt = atomic_dec_return(&lport->act_rport_cnt);
+	if (cnt == 0 && lport->localport.port_state == FC_OBJSTATE_DELETED)
+		lport->ops->localport_delete(&lport->localport);
+}
+
+static int
+nvme_fc_ctlr_active_on_rport(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_rport *rport = ctrl->rport;
+	u32 cnt;
+
+	if (ctrl->assoc_active)
+		return 1;
+
+	ctrl->assoc_active = true;
+	cnt = atomic_inc_return(&rport->act_ctrl_cnt);
+	if (cnt == 1)
+		nvme_fc_rport_active_on_lport(rport);
+
+	return 0;
+}
+
+static int
+nvme_fc_ctlr_inactive_on_rport(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvme_fc_rport *rport = ctrl->rport;
+	struct nvme_fc_lport *lport = rport->lport;
+	u32 cnt;
+
+	/* ctrl->assoc_active=false will be set independently */
+
+	cnt = atomic_dec_return(&rport->act_ctrl_cnt);
+	if (cnt == 0) {
+		if (rport->remoteport.port_state == FC_OBJSTATE_DELETED)
+			lport->ops->remoteport_delete(&rport->remoteport);
+		nvme_fc_rport_inactive_on_lport(rport);
+	}
+
+	return 0;
+}
+
+/*
+ * This routine restarts the controller on the host side, and
+ * on the link side, recreates the controller association.
+ */
+static int
+nvme_fc_create_association(struct nvme_fc_ctrl *ctrl)
+{
+	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
+	int ret;
+	bool changed;
+
+	++ctrl->ctrl.nr_reconnects;
+
+	if (ctrl->rport->remoteport.port_state != FC_OBJSTATE_ONLINE)
+		return -ENODEV;
+
+	if (nvme_fc_ctlr_active_on_rport(ctrl))
+		return -ENOTUNIQ;
+
+	/*
+	 * Create the admin queue
+	 */
+
+	ret = __nvme_fc_create_hw_queue(ctrl, &ctrl->queues[0], 0,
+				NVME_AQ_DEPTH);
+	if (ret)
+		goto out_free_queue;
+
+	ret = nvme_fc_connect_admin_queue(ctrl, &ctrl->queues[0],
+				NVME_AQ_DEPTH, (NVME_AQ_DEPTH / 4));
+	if (ret)
+		goto out_delete_hw_queue;
+
+	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
+
+	ret = nvmf_connect_admin_queue(&ctrl->ctrl);
+	if (ret)
+		goto out_disconnect_admin_queue;
+
+	set_bit(NVME_FC_Q_LIVE, &ctrl->queues[0].flags);
+
+	/*
+	 * Check controller capabilities
+	 *
+	 * todo:- add code to check if ctrl attributes changed from
+	 * prior connection values
+	 */
+
+	ret = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->ctrl.cap);
+	if (ret) {
+		dev_err(ctrl->ctrl.device,
+			"prop_get NVME_REG_CAP failed\n");
+		goto out_disconnect_admin_queue;
+	}
+
+	ctrl->ctrl.sqsize =
+		min_t(int, NVME_CAP_MQES(ctrl->ctrl.cap), ctrl->ctrl.sqsize);
+
+	ret = nvme_enable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
+	if (ret)
+		goto out_disconnect_admin_queue;
+
+	ctrl->ctrl.max_hw_sectors =
+		(ctrl->lport->ops->max_sgl_segments - 1) << (PAGE_SHIFT - 9);
+
+	ret = nvme_init_identify(&ctrl->ctrl);
+	if (ret)
+		goto out_disconnect_admin_queue;
+
+	/* sanity checks */
+
+	/* FC-NVME does not have other data in the capsule */
+	if (ctrl->ctrl.icdoff) {
+		dev_err(ctrl->ctrl.device, "icdoff %d is not supported!\n",
+				ctrl->ctrl.icdoff);
+		goto out_disconnect_admin_queue;
+	}
+
+	/* FC-NVME supports normal SGL Data Block Descriptors */
+
+	if (opts->queue_size > ctrl->ctrl.maxcmd) {
+		/* warn if maxcmd is lower than queue_size */
+		dev_warn(ctrl->ctrl.device,
+			"queue_size %zu > ctrl maxcmd %u, reducing "
+			"to queue_size\n",
+			opts->queue_size, ctrl->ctrl.maxcmd);
+		opts->queue_size = ctrl->ctrl.maxcmd;
+	}
+
+	if (opts->queue_size > ctrl->ctrl.sqsize + 1) {
+		/* warn if sqsize is lower than queue_size */
+		dev_warn(ctrl->ctrl.device,
+			"queue_size %zu > ctrl sqsize %u, clamping down\n",
+			opts->queue_size, ctrl->ctrl.sqsize + 1);
+		opts->queue_size = ctrl->ctrl.sqsize + 1;
+	}
+
+	ret = nvme_fc_init_aen_ops(ctrl);
+	if (ret)
+		goto out_term_aen_ops;
+
+	/*
+	 * Create the io queues
+	 */
+
+	if (ctrl->ctrl.queue_count > 1) {
+		if (!ctrl->ioq_live)
+			ret = nvme_fc_create_io_queues(ctrl);
+		else
+			ret = nvme_fc_recreate_io_queues(ctrl);
+		if (ret)
+			goto out_term_aen_ops;
+	}
+
+	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
+
+	ctrl->ctrl.nr_reconnects = 0;
+
+	if (changed)
+		nvme_start_ctrl(&ctrl->ctrl);
+
+	return 0;	/* Success */
+
+out_term_aen_ops:
+	nvme_fc_term_aen_ops(ctrl);
+out_disconnect_admin_queue:
+	/* send a Disconnect(association) LS to fc-nvme target */
+	nvme_fc_xmt_disconnect_assoc(ctrl);
+out_delete_hw_queue:
+	__nvme_fc_delete_hw_queue(ctrl, &ctrl->queues[0], 0);
+out_free_queue:
+	nvme_fc_free_queue(&ctrl->queues[0]);
+	ctrl->assoc_active = false;
+	nvme_fc_ctlr_inactive_on_rport(ctrl);
+
+	return ret;
+}
+
+/*
+ * This routine stops operation of the controller on the host side.
+ * On the host os stack side: Admin and IO queues are stopped,
+ *   outstanding ios on them terminated via FC ABTS.
+ * On the link side: the association is terminated.
+ */
+static void
+nvme_fc_delete_association(struct nvme_fc_ctrl *ctrl)
+{
+	unsigned long flags;
+
+	if (!ctrl->assoc_active)
+		return;
+	ctrl->assoc_active = false;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	ctrl->flags |= FCCTRL_TERMIO;
+	ctrl->iocnt = 0;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+
+	/*
+	 * If io queues are present, stop them and terminate all outstanding
+	 * ios on them. As FC allocates FC exchange for each io, the
+	 * transport must contact the LLDD to terminate the exchange,
+	 * thus releasing the FC exchange. We use blk_mq_tagset_busy_itr()
+	 * to tell us what io's are busy and invoke a transport routine
+	 * to kill them with the LLDD.  After terminating the exchange
+	 * the LLDD will call the transport's normal io done path, but it
+	 * will have an aborted status. The done path will return the
+	 * io requests back to the block layer as part of normal completions
+	 * (but with error status).
+	 */
+	if (ctrl->ctrl.queue_count > 1) {
+		nvme_stop_queues(&ctrl->ctrl);
+		blk_mq_tagset_busy_iter(&ctrl->tag_set,
+				nvme_fc_terminate_exchange, &ctrl->ctrl);
+	}
+
+	/*
+	 * Other transports, which don't have link-level contexts bound
+	 * to sqe's, would try to gracefully shutdown the controller by
+	 * writing the registers for shutdown and polling (call
+	 * nvme_shutdown_ctrl()). Given a bunch of i/o was potentially
+	 * just aborted and we will wait on those contexts, and given
+	 * there was no indication of how live the controlelr is on the
+	 * link, don't send more io to create more contexts for the
+	 * shutdown. Let the controller fail via keepalive failure if
+	 * its still present.
+	 */
+
+	/*
+	 * clean up the admin queue. Same thing as above.
+	 * use blk_mq_tagset_busy_itr() and the transport routine to
+	 * terminate the exchanges.
+	 */
+	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
+	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
+				nvme_fc_terminate_exchange, &ctrl->ctrl);
+
+	/* kill the aens as they are a separate path */
+	nvme_fc_abort_aen_ops(ctrl);
+
+	/* wait for all io that had to be aborted */
+	spin_lock_irq(&ctrl->lock);
+	wait_event_lock_irq(ctrl->ioabort_wait, ctrl->iocnt == 0, ctrl->lock);
+	ctrl->flags &= ~FCCTRL_TERMIO;
+	spin_unlock_irq(&ctrl->lock);
+
+	nvme_fc_term_aen_ops(ctrl);
+
+	/*
+	 * send a Disconnect(association) LS to fc-nvme target
+	 * Note: could have been sent at top of process, but
+	 * cleaner on link traffic if after the aborts complete.
+	 * Note: if association doesn't exist, association_id will be 0
+	 */
+	if (ctrl->association_id)
+		nvme_fc_xmt_disconnect_assoc(ctrl);
+
+	if (ctrl->ctrl.tagset) {
+		nvme_fc_delete_hw_io_queues(ctrl);
+		nvme_fc_free_io_queues(ctrl);
+	}
+
+	__nvme_fc_delete_hw_queue(ctrl, &ctrl->queues[0], 0);
+	nvme_fc_free_queue(&ctrl->queues[0]);
+
+	/* re-enable the admin_q so anything new can fast fail */
+	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
+
+	/* resume the io queues so that things will fast fail */
+	nvme_start_queues(&ctrl->ctrl);
+
+	nvme_fc_ctlr_inactive_on_rport(ctrl);
+}
+
+static void
+nvme_fc_delete_ctrl(struct nvme_ctrl *nctrl)
+{
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(nctrl);
+
+	cancel_work_sync(&ctrl->err_work);
+	cancel_delayed_work_sync(&ctrl->connect_work);
+	/*
+	 * kill the association on the link side.  this will block
+	 * waiting for io to terminate
+	 */
+	nvme_fc_delete_association(ctrl);
+}
+
+static void
+nvme_fc_reconnect_or_delete(struct nvme_fc_ctrl *ctrl, int status)
+{
+	struct nvme_fc_rport *rport = ctrl->rport;
+	struct nvme_fc_remote_port *portptr = &rport->remoteport;
+	unsigned long recon_delay = ctrl->ctrl.opts->reconnect_delay * HZ;
+	bool recon = true;
+
+	if (ctrl->ctrl.state != NVME_CTRL_CONNECTING)
+		return;
+
+	if (portptr->port_state == FC_OBJSTATE_ONLINE)
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: reset: Reconnect attempt failed (%d)\n",
+			ctrl->cnum, status);
+	else if (time_after_eq(jiffies, rport->dev_loss_end))
+		recon = false;
+
+	if (recon && nvmf_should_reconnect(&ctrl->ctrl)) {
+		if (portptr->port_state == FC_OBJSTATE_ONLINE)
+			dev_info(ctrl->ctrl.device,
+				"NVME-FC{%d}: Reconnect attempt in %ld "
+				"seconds\n",
+				ctrl->cnum, recon_delay / HZ);
+		else if (time_after(jiffies + recon_delay, rport->dev_loss_end))
+			recon_delay = rport->dev_loss_end - jiffies;
+
+		queue_delayed_work(nvme_wq, &ctrl->connect_work, recon_delay);
+	} else {
+		if (portptr->port_state == FC_OBJSTATE_ONLINE)
+			dev_warn(ctrl->ctrl.device,
+				"NVME-FC{%d}: Max reconnect attempts (%d) "
+				"reached.\n",
+				ctrl->cnum, ctrl->ctrl.nr_reconnects);
+		else
+			dev_warn(ctrl->ctrl.device,
+				"NVME-FC{%d}: dev_loss_tmo (%d) expired "
+				"while waiting for remoteport connectivity.\n",
+				ctrl->cnum, portptr->dev_loss_tmo);
+		WARN_ON(nvme_delete_ctrl(&ctrl->ctrl));
+	}
+}
+
+static void
+__nvme_fc_terminate_io(struct nvme_fc_ctrl *ctrl)
+{
+	/*
+	 * if state is connecting - the error occurred as part of a
+	 * reconnect attempt. The create_association error paths will
+	 * clean up any outstanding io.
+	 *
+	 * if it's a different state - ensure all pending io is
+	 * terminated. Given this can delay while waiting for the
+	 * aborted io to return, we recheck adapter state below
+	 * before changing state.
+	 */
+	if (ctrl->ctrl.state != NVME_CTRL_CONNECTING) {
+		nvme_stop_keep_alive(&ctrl->ctrl);
+
+		/* will block will waiting for io to terminate */
+		nvme_fc_delete_association(ctrl);
+	}
+
+	if (ctrl->ctrl.state != NVME_CTRL_CONNECTING &&
+	    !nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
+		dev_err(ctrl->ctrl.device,
+			"NVME-FC{%d}: error_recovery: Couldn't change state "
+			"to CONNECTING\n", ctrl->cnum);
+}
+
+static void
+nvme_fc_reset_ctrl_work(struct work_struct *work)
+{
+	struct nvme_fc_ctrl *ctrl =
+		container_of(work, struct nvme_fc_ctrl, ctrl.reset_work);
+	int ret;
+
+	__nvme_fc_terminate_io(ctrl);
+
+	nvme_stop_ctrl(&ctrl->ctrl);
+
+	if (ctrl->rport->remoteport.port_state == FC_OBJSTATE_ONLINE)
+		ret = nvme_fc_create_association(ctrl);
+	else
+		ret = -ENOTCONN;
+
+	if (ret)
+		nvme_fc_reconnect_or_delete(ctrl, ret);
+	else
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: controller reset complete\n",
+			ctrl->cnum);
+}
+
+static void
+nvme_fc_connect_err_work(struct work_struct *work)
+{
+	struct nvme_fc_ctrl *ctrl =
+			container_of(work, struct nvme_fc_ctrl, err_work);
+
+	__nvme_fc_terminate_io(ctrl);
+
+	atomic_set(&ctrl->err_work_active, 0);
+
+	/*
+	 * Rescheduling the connection after recovering
+	 * from the io error is left to the reconnect work
+	 * item, which is what should have stalled waiting on
+	 * the io that had the error that scheduled this work.
+	 */
+}
+
+static const struct nvme_ctrl_ops nvme_fc_ctrl_ops = {
+	.name			= "fc",
+	.module			= THIS_MODULE,
+	.flags			= NVME_F_FABRICS,
+	.reg_read32		= nvmf_reg_read32,
+	.reg_read64		= nvmf_reg_read64,
+	.reg_write32		= nvmf_reg_write32,
+	.free_ctrl		= nvme_fc_nvme_ctrl_freed,
+	.submit_async_event	= nvme_fc_submit_async_event,
+	.delete_ctrl		= nvme_fc_delete_ctrl,
+	.get_address		= nvmf_get_address,
+};
+
+static void
+nvme_fc_connect_ctrl_work(struct work_struct *work)
+{
+	int ret;
+
+	struct nvme_fc_ctrl *ctrl =
+			container_of(to_delayed_work(work),
+				struct nvme_fc_ctrl, connect_work);
+
+	ret = nvme_fc_create_association(ctrl);
+	if (ret)
+		nvme_fc_reconnect_or_delete(ctrl, ret);
+	else
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: controller connect complete\n",
+			ctrl->cnum);
+}
+
+
+static const struct blk_mq_ops nvme_fc_admin_mq_ops = {
+	.queue_rq	= nvme_fc_queue_rq,
+	.complete	= nvme_fc_complete_rq,
+	.init_request	= nvme_fc_init_request,
+	.exit_request	= nvme_fc_exit_request,
+	.init_hctx	= nvme_fc_init_admin_hctx,
+	.timeout	= nvme_fc_timeout,
+};
+
+
+/*
+ * Fails a controller request if it matches an existing controller
+ * (association) with the same tuple:
+ * <Host NQN, Host ID, local FC port, remote FC port, SUBSYS NQN>
+ *
+ * The ports don't need to be compared as they are intrinsically
+ * already matched by the port pointers supplied.
+ */
+static bool
+nvme_fc_existing_controller(struct nvme_fc_rport *rport,
+		struct nvmf_ctrl_options *opts)
+{
+	struct nvme_fc_ctrl *ctrl;
+	unsigned long flags;
+	bool found = false;
+
+	spin_lock_irqsave(&rport->lock, flags);
+	list_for_each_entry(ctrl, &rport->ctrl_list, ctrl_list) {
+		found = nvmf_ctlr_matches_baseopts(&ctrl->ctrl, opts);
+		if (found)
+			break;
+	}
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	return found;
+}
+
+static struct nvme_ctrl *
+nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
+	struct nvme_fc_lport *lport, struct nvme_fc_rport *rport)
+{
+	struct nvme_fc_ctrl *ctrl;
+	unsigned long flags;
+	int ret, idx;
+
+	if (!(rport->remoteport.port_role &
+	    (FC_PORT_ROLE_NVME_DISCOVERY | FC_PORT_ROLE_NVME_TARGET))) {
+		ret = -EBADR;
+		goto out_fail;
+	}
+
+	if (!opts->duplicate_connect &&
+	    nvme_fc_existing_controller(rport, opts)) {
+		ret = -EALREADY;
+		goto out_fail;
+	}
+
+	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
+	if (!ctrl) {
+		ret = -ENOMEM;
+		goto out_fail;
+	}
+
+	idx = ida_simple_get(&nvme_fc_ctrl_cnt, 0, 0, GFP_KERNEL);
+	if (idx < 0) {
+		ret = -ENOSPC;
+		goto out_free_ctrl;
+	}
+
+	ctrl->ctrl.opts = opts;
+	ctrl->ctrl.nr_reconnects = 0;
+	INIT_LIST_HEAD(&ctrl->ctrl_list);
+	ctrl->lport = lport;
+	ctrl->rport = rport;
+	ctrl->dev = lport->dev;
+	ctrl->cnum = idx;
+	ctrl->ioq_live = false;
+	ctrl->assoc_active = false;
+	atomic_set(&ctrl->err_work_active, 0);
+	init_waitqueue_head(&ctrl->ioabort_wait);
+
+	get_device(ctrl->dev);
+	kref_init(&ctrl->ref);
+
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_fc_reset_ctrl_work);
+	INIT_DELAYED_WORK(&ctrl->connect_work, nvme_fc_connect_ctrl_work);
+	INIT_WORK(&ctrl->err_work, nvme_fc_connect_err_work);
+	spin_lock_init(&ctrl->lock);
+
+	/* io queue count */
+	ctrl->ctrl.queue_count = min_t(unsigned int,
+				opts->nr_io_queues,
+				lport->ops->max_hw_queues);
+	ctrl->ctrl.queue_count++;	/* +1 for admin queue */
+
+	ctrl->ctrl.sqsize = opts->queue_size - 1;
+	ctrl->ctrl.kato = opts->kato;
+	ctrl->ctrl.cntlid = 0xffff;
+
+	ret = -ENOMEM;
+	ctrl->queues = kcalloc(ctrl->ctrl.queue_count,
+				sizeof(struct nvme_fc_queue), GFP_KERNEL);
+	if (!ctrl->queues)
+		goto out_free_ida;
+
+	nvme_fc_init_queue(ctrl, 0);
+
+	memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set));
+	ctrl->admin_tag_set.ops = &nvme_fc_admin_mq_ops;
+	ctrl->admin_tag_set.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
+	ctrl->admin_tag_set.reserved_tags = 2; /* fabric connect + Keep-Alive */
+	ctrl->admin_tag_set.numa_node = NUMA_NO_NODE;
+	ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_fc_fcp_op) +
+					(SG_CHUNK_SIZE *
+						sizeof(struct scatterlist)) +
+					ctrl->lport->ops->fcprqst_priv_sz;
+	ctrl->admin_tag_set.driver_data = ctrl;
+	ctrl->admin_tag_set.nr_hw_queues = 1;
+	ctrl->admin_tag_set.timeout = ADMIN_TIMEOUT;
+	ctrl->admin_tag_set.flags = BLK_MQ_F_NO_SCHED;
+
+	ret = blk_mq_alloc_tag_set(&ctrl->admin_tag_set);
+	if (ret)
+		goto out_free_queues;
+	ctrl->ctrl.admin_tagset = &ctrl->admin_tag_set;
+
+	ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
+	if (IS_ERR(ctrl->ctrl.admin_q)) {
+		ret = PTR_ERR(ctrl->ctrl.admin_q);
+		goto out_free_admin_tag_set;
+	}
+
+	/*
+	 * Would have been nice to init io queues tag set as well.
+	 * However, we require interaction from the controller
+	 * for max io queue count before we can do so.
+	 * Defer this to the connect path.
+	 */
+
+	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_fc_ctrl_ops, 0);
+	if (ret)
+		goto out_cleanup_admin_q;
+
+	/* at this point, teardown path changes to ref counting on nvme ctrl */
+
+	spin_lock_irqsave(&rport->lock, flags);
+	list_add_tail(&ctrl->ctrl_list, &rport->ctrl_list);
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING) ||
+	    !nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
+		dev_err(ctrl->ctrl.device,
+			"NVME-FC{%d}: failed to init ctrl state\n", ctrl->cnum);
+		goto fail_ctrl;
+	}
+
+	nvme_get_ctrl(&ctrl->ctrl);
+
+	if (!queue_delayed_work(nvme_wq, &ctrl->connect_work, 0)) {
+		nvme_put_ctrl(&ctrl->ctrl);
+		dev_err(ctrl->ctrl.device,
+			"NVME-FC{%d}: failed to schedule initial connect\n",
+			ctrl->cnum);
+		goto fail_ctrl;
+	}
+
+	flush_delayed_work(&ctrl->connect_work);
+
+	dev_info(ctrl->ctrl.device,
+		"NVME-FC{%d}: new ctrl: NQN \"%s\"\n",
+		ctrl->cnum, ctrl->ctrl.opts->subsysnqn);
+
+	return &ctrl->ctrl;
+
+fail_ctrl:
+	nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING);
+	cancel_work_sync(&ctrl->ctrl.reset_work);
+	cancel_work_sync(&ctrl->err_work);
+	cancel_delayed_work_sync(&ctrl->connect_work);
+
+	ctrl->ctrl.opts = NULL;
+
+	/* initiate nvme ctrl ref counting teardown */
+	nvme_uninit_ctrl(&ctrl->ctrl);
+
+	/* Remove core ctrl ref. */
+	nvme_put_ctrl(&ctrl->ctrl);
+
+	/* as we're past the point where we transition to the ref
+	 * counting teardown path, if we return a bad pointer here,
+	 * the calling routine, thinking it's prior to the
+	 * transition, will do an rport put. Since the teardown
+	 * path also does a rport put, we do an extra get here to
+	 * so proper order/teardown happens.
+	 */
+	nvme_fc_rport_get(rport);
+
+	return ERR_PTR(-EIO);
+
+out_cleanup_admin_q:
+	blk_cleanup_queue(ctrl->ctrl.admin_q);
+out_free_admin_tag_set:
+	blk_mq_free_tag_set(&ctrl->admin_tag_set);
+out_free_queues:
+	kfree(ctrl->queues);
+out_free_ida:
+	put_device(ctrl->dev);
+	ida_simple_remove(&nvme_fc_ctrl_cnt, ctrl->cnum);
+out_free_ctrl:
+	kfree(ctrl);
+out_fail:
+	/* exit via here doesn't follow ctlr ref points */
+	return ERR_PTR(ret);
+}
+
+
+struct nvmet_fc_traddr {
+	u64	nn;
+	u64	pn;
+};
+
+static int
+__nvme_fc_parse_u64(substring_t *sstr, u64 *val)
+{
+	u64 token64;
+
+	if (match_u64(sstr, &token64))
+		return -EINVAL;
+	*val = token64;
+
+	return 0;
+}
+
+/*
+ * This routine validates and extracts the WWN's from the TRADDR string.
+ * As kernel parsers need the 0x to determine number base, universally
+ * build string to parse with 0x prefix before parsing name strings.
+ */
+static int
+nvme_fc_parse_traddr(struct nvmet_fc_traddr *traddr, char *buf, size_t blen)
+{
+	char name[2 + NVME_FC_TRADDR_HEXNAMELEN + 1];
+	substring_t wwn = { name, &name[sizeof(name)-1] };
+	int nnoffset, pnoffset;
+
+	/* validate it string one of the 2 allowed formats */
+	if (strnlen(buf, blen) == NVME_FC_TRADDR_MAXLENGTH &&
+			!strncmp(buf, "nn-0x", NVME_FC_TRADDR_OXNNLEN) &&
+			!strncmp(&buf[NVME_FC_TRADDR_MAX_PN_OFFSET],
+				"pn-0x", NVME_FC_TRADDR_OXNNLEN)) {
+		nnoffset = NVME_FC_TRADDR_OXNNLEN;
+		pnoffset = NVME_FC_TRADDR_MAX_PN_OFFSET +
+						NVME_FC_TRADDR_OXNNLEN;
+	} else if ((strnlen(buf, blen) == NVME_FC_TRADDR_MINLENGTH &&
+			!strncmp(buf, "nn-", NVME_FC_TRADDR_NNLEN) &&
+			!strncmp(&buf[NVME_FC_TRADDR_MIN_PN_OFFSET],
+				"pn-", NVME_FC_TRADDR_NNLEN))) {
+		nnoffset = NVME_FC_TRADDR_NNLEN;
+		pnoffset = NVME_FC_TRADDR_MIN_PN_OFFSET + NVME_FC_TRADDR_NNLEN;
+	} else
+		goto out_einval;
+
+	name[0] = '0';
+	name[1] = 'x';
+	name[2 + NVME_FC_TRADDR_HEXNAMELEN] = 0;
+
+	memcpy(&name[2], &buf[nnoffset], NVME_FC_TRADDR_HEXNAMELEN);
+	if (__nvme_fc_parse_u64(&wwn, &traddr->nn))
+		goto out_einval;
+
+	memcpy(&name[2], &buf[pnoffset], NVME_FC_TRADDR_HEXNAMELEN);
+	if (__nvme_fc_parse_u64(&wwn, &traddr->pn))
+		goto out_einval;
+
+	return 0;
+
+out_einval:
+	pr_warn("%s: bad traddr string\n", __func__);
+	return -EINVAL;
+}
+
+static struct nvme_ctrl *
+nvme_fc_create_ctrl(struct device *dev, struct nvmf_ctrl_options *opts)
+{
+	struct nvme_fc_lport *lport;
+	struct nvme_fc_rport *rport;
+	struct nvme_ctrl *ctrl;
+	struct nvmet_fc_traddr laddr = { 0L, 0L };
+	struct nvmet_fc_traddr raddr = { 0L, 0L };
+	unsigned long flags;
+	int ret;
+
+	ret = nvme_fc_parse_traddr(&raddr, opts->traddr, NVMF_TRADDR_SIZE);
+	if (ret || !raddr.nn || !raddr.pn)
+		return ERR_PTR(-EINVAL);
+
+	ret = nvme_fc_parse_traddr(&laddr, opts->host_traddr, NVMF_TRADDR_SIZE);
+	if (ret || !laddr.nn || !laddr.pn)
+		return ERR_PTR(-EINVAL);
+
+	/* find the host and remote ports to connect together */
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	list_for_each_entry(lport, &nvme_fc_lport_list, port_list) {
+		if (lport->localport.node_name != laddr.nn ||
+		    lport->localport.port_name != laddr.pn ||
+		    lport->localport.port_state != FC_OBJSTATE_ONLINE)
+			continue;
+
+		list_for_each_entry(rport, &lport->endp_list, endp_list) {
+			if (rport->remoteport.node_name != raddr.nn ||
+			    rport->remoteport.port_name != raddr.pn ||
+			    rport->remoteport.port_state != FC_OBJSTATE_ONLINE)
+				continue;
+
+			/* if fail to get reference fall through. Will error */
+			if (!nvme_fc_rport_get(rport))
+				break;
+
+			spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+			ctrl = nvme_fc_init_ctrl(dev, opts, lport, rport);
+			if (IS_ERR(ctrl))
+				nvme_fc_rport_put(rport);
+			return ctrl;
+		}
+	}
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	pr_warn("%s: %s - %s combination not found\n",
+		__func__, opts->traddr, opts->host_traddr);
+	return ERR_PTR(-ENOENT);
+}
+
+
+static struct nvmf_transport_ops nvme_fc_transport = {
+	.name		= "fc",
+	.module		= THIS_MODULE,
+	.required_opts	= NVMF_OPT_TRADDR | NVMF_OPT_HOST_TRADDR,
+	.allowed_opts	= NVMF_OPT_RECONNECT_DELAY | NVMF_OPT_CTRL_LOSS_TMO,
+	.create_ctrl	= nvme_fc_create_ctrl,
+};
+
+static int __init nvme_fc_init_module(void)
+{
+	int ret;
+
+	nvme_fc_wq = alloc_workqueue("nvme_fc_wq", WQ_MEM_RECLAIM, 0);
+	if (!nvme_fc_wq)
+		return -ENOMEM;
+
+	/*
+	 * NOTE:
+	 * It is expected that in the future the kernel will combine
+	 * the FC-isms that are currently under scsi and now being
+	 * added to by NVME into a new standalone FC class. The SCSI
+	 * and NVME protocols and their devices would be under this
+	 * new FC class.
+	 *
+	 * As we need something to post FC-specific udev events to,
+	 * specifically for nvme probe events, start by creating the
+	 * new device class.  When the new standalone FC class is
+	 * put in place, this code will move to a more generic
+	 * location for the class.
+	 */
+	fc_class = class_create(THIS_MODULE, "fc");
+	if (IS_ERR(fc_class)) {
+		pr_err("couldn't register class fc\n");
+		ret = PTR_ERR(fc_class);
+		goto out_destroy_wq;
+	}
+
+	/*
+	 * Create a device for the FC-centric udev events
+	 */
+	fc_udev_device = device_create(fc_class, NULL, MKDEV(0, 0), NULL,
+				"fc_udev_device");
+	if (IS_ERR(fc_udev_device)) {
+		pr_err("couldn't create fc_udev device!\n");
+		ret = PTR_ERR(fc_udev_device);
+		goto out_destroy_class;
+	}
+
+	ret = nvmf_register_transport(&nvme_fc_transport);
+	if (ret)
+		goto out_destroy_device;
+
+	return 0;
+
+out_destroy_device:
+	device_destroy(fc_class, MKDEV(0, 0));
+out_destroy_class:
+	class_destroy(fc_class);
+out_destroy_wq:
+	destroy_workqueue(nvme_fc_wq);
+
+	return ret;
+}
+
+static void __exit nvme_fc_exit_module(void)
+{
+	/* sanity check - all lports should be removed */
+	if (!list_empty(&nvme_fc_lport_list))
+		pr_warn("%s: localport list not empty\n", __func__);
+
+	nvmf_unregister_transport(&nvme_fc_transport);
+
+	ida_destroy(&nvme_fc_local_port_cnt);
+	ida_destroy(&nvme_fc_ctrl_cnt);
+
+	device_destroy(fc_class, MKDEV(0, 0));
+	class_destroy(fc_class);
+	destroy_workqueue(nvme_fc_wq);
+}
+
+module_init(nvme_fc_init_module);
+module_exit(nvme_fc_exit_module);
+
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
new file mode 100644
index 000000000..d10257b9c
--- /dev/null
+++ b/drivers/nvme/host/lightnvm.c
@@ -0,0 +1,1294 @@
+/*
+ * nvme-lightnvm.c - LightNVM NVMe device
+ *
+ * Copyright (C) 2014-2015 IT University of Copenhagen
+ * Initial release: Matias Bjorling <mb@lightnvm.io>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ * USA.
+ *
+ */
+
+#include "nvme.h"
+
+#include <linux/nvme.h>
+#include <linux/bitops.h>
+#include <linux/lightnvm.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/sysctl.h>
+#include <uapi/linux/lightnvm.h>
+
+enum nvme_nvm_admin_opcode {
+	nvme_nvm_admin_identity		= 0xe2,
+	nvme_nvm_admin_get_bb_tbl	= 0xf2,
+	nvme_nvm_admin_set_bb_tbl	= 0xf1,
+};
+
+enum nvme_nvm_log_page {
+	NVME_NVM_LOG_REPORT_CHUNK	= 0xca,
+};
+
+struct nvme_nvm_ph_rw {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2;
+	__le64			metadata;
+	__le64			prp1;
+	__le64			prp2;
+	__le64			spba;
+	__le16			length;
+	__le16			control;
+	__le32			dsmgmt;
+	__le64			resv;
+};
+
+struct nvme_nvm_erase_blk {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le64			spba;
+	__le16			length;
+	__le16			control;
+	__le32			dsmgmt;
+	__le64			resv;
+};
+
+struct nvme_nvm_identity {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd[2];
+	__le64			prp1;
+	__le64			prp2;
+	__u32			rsvd11[6];
+};
+
+struct nvme_nvm_getbbtbl {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le64			spba;
+	__u32			rsvd4[4];
+};
+
+struct nvme_nvm_setbbtbl {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__le64			rsvd[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le64			spba;
+	__le16			nlb;
+	__u8			value;
+	__u8			rsvd3;
+	__u32			rsvd4[3];
+};
+
+struct nvme_nvm_command {
+	union {
+		struct nvme_common_command common;
+		struct nvme_nvm_ph_rw ph_rw;
+		struct nvme_nvm_erase_blk erase;
+		struct nvme_nvm_identity identity;
+		struct nvme_nvm_getbbtbl get_bb;
+		struct nvme_nvm_setbbtbl set_bb;
+	};
+};
+
+struct nvme_nvm_id12_grp {
+	__u8			mtype;
+	__u8			fmtype;
+	__le16			res16;
+	__u8			num_ch;
+	__u8			num_lun;
+	__u8			num_pln;
+	__u8			rsvd1;
+	__le16			num_chk;
+	__le16			num_pg;
+	__le16			fpg_sz;
+	__le16			csecs;
+	__le16			sos;
+	__le16			rsvd2;
+	__le32			trdt;
+	__le32			trdm;
+	__le32			tprt;
+	__le32			tprm;
+	__le32			tbet;
+	__le32			tbem;
+	__le32			mpos;
+	__le32			mccap;
+	__le16			cpar;
+	__u8			reserved[906];
+} __packed;
+
+struct nvme_nvm_id12_addrf {
+	__u8			ch_offset;
+	__u8			ch_len;
+	__u8			lun_offset;
+	__u8			lun_len;
+	__u8			pln_offset;
+	__u8			pln_len;
+	__u8			blk_offset;
+	__u8			blk_len;
+	__u8			pg_offset;
+	__u8			pg_len;
+	__u8			sec_offset;
+	__u8			sec_len;
+	__u8			res[4];
+} __packed;
+
+struct nvme_nvm_id12 {
+	__u8			ver_id;
+	__u8			vmnt;
+	__u8			cgrps;
+	__u8			res;
+	__le32			cap;
+	__le32			dom;
+	struct nvme_nvm_id12_addrf ppaf;
+	__u8			resv[228];
+	struct nvme_nvm_id12_grp grp;
+	__u8			resv2[2880];
+} __packed;
+
+struct nvme_nvm_bb_tbl {
+	__u8	tblid[4];
+	__le16	verid;
+	__le16	revid;
+	__le32	rvsd1;
+	__le32	tblks;
+	__le32	tfact;
+	__le32	tgrown;
+	__le32	tdresv;
+	__le32	thresv;
+	__le32	rsvd2[8];
+	__u8	blk[0];
+};
+
+struct nvme_nvm_id20_addrf {
+	__u8			grp_len;
+	__u8			pu_len;
+	__u8			chk_len;
+	__u8			lba_len;
+	__u8			resv[4];
+};
+
+struct nvme_nvm_id20 {
+	__u8			mjr;
+	__u8			mnr;
+	__u8			resv[6];
+
+	struct nvme_nvm_id20_addrf lbaf;
+
+	__le32			mccap;
+	__u8			resv2[12];
+
+	__u8			wit;
+	__u8			resv3[31];
+
+	/* Geometry */
+	__le16			num_grp;
+	__le16			num_pu;
+	__le32			num_chk;
+	__le32			clba;
+	__u8			resv4[52];
+
+	/* Write data requirements */
+	__le32			ws_min;
+	__le32			ws_opt;
+	__le32			mw_cunits;
+	__le32			maxoc;
+	__le32			maxocpu;
+	__u8			resv5[44];
+
+	/* Performance related metrics */
+	__le32			trdt;
+	__le32			trdm;
+	__le32			twrt;
+	__le32			twrm;
+	__le32			tcrst;
+	__le32			tcrsm;
+	__u8			resv6[40];
+
+	/* Reserved area */
+	__u8			resv7[2816];
+
+	/* Vendor specific */
+	__u8			vs[1024];
+};
+
+struct nvme_nvm_chk_meta {
+	__u8	state;
+	__u8	type;
+	__u8	wi;
+	__u8	rsvd[5];
+	__le64	slba;
+	__le64	cnlb;
+	__le64	wp;
+};
+
+/*
+ * Check we didn't inadvertently grow the command struct
+ */
+static inline void _nvme_nvm_check_size(void)
+{
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_identity) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_ph_rw) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_erase_blk) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_getbbtbl) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_setbbtbl) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id12_grp) != 960);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id12_addrf) != 16);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id12) != NVME_IDENTIFY_DATA_SIZE);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_bb_tbl) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id20_addrf) != 8);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id20) != NVME_IDENTIFY_DATA_SIZE);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_chk_meta) != 32);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_chk_meta) !=
+						sizeof(struct nvm_chk_meta));
+}
+
+static void nvme_nvm_set_addr_12(struct nvm_addrf_12 *dst,
+				 struct nvme_nvm_id12_addrf *src)
+{
+	dst->ch_len = src->ch_len;
+	dst->lun_len = src->lun_len;
+	dst->blk_len = src->blk_len;
+	dst->pg_len = src->pg_len;
+	dst->pln_len = src->pln_len;
+	dst->sec_len = src->sec_len;
+
+	dst->ch_offset = src->ch_offset;
+	dst->lun_offset = src->lun_offset;
+	dst->blk_offset = src->blk_offset;
+	dst->pg_offset = src->pg_offset;
+	dst->pln_offset = src->pln_offset;
+	dst->sec_offset = src->sec_offset;
+
+	dst->ch_mask = ((1ULL << dst->ch_len) - 1) << dst->ch_offset;
+	dst->lun_mask = ((1ULL << dst->lun_len) - 1) << dst->lun_offset;
+	dst->blk_mask = ((1ULL << dst->blk_len) - 1) << dst->blk_offset;
+	dst->pg_mask = ((1ULL << dst->pg_len) - 1) << dst->pg_offset;
+	dst->pln_mask = ((1ULL << dst->pln_len) - 1) << dst->pln_offset;
+	dst->sec_mask = ((1ULL << dst->sec_len) - 1) << dst->sec_offset;
+}
+
+static int nvme_nvm_setup_12(struct nvme_nvm_id12 *id,
+			     struct nvm_geo *geo)
+{
+	struct nvme_nvm_id12_grp *src;
+	int sec_per_pg, sec_per_pl, pg_per_blk;
+
+	if (id->cgrps != 1)
+		return -EINVAL;
+
+	src = &id->grp;
+
+	if (src->mtype != 0) {
+		pr_err("nvm: memory type not supported\n");
+		return -EINVAL;
+	}
+
+	/* 1.2 spec. only reports a single version id - unfold */
+	geo->major_ver_id = id->ver_id;
+	geo->minor_ver_id = 2;
+
+	/* Set compacted version for upper layers */
+	geo->version = NVM_OCSSD_SPEC_12;
+
+	geo->num_ch = src->num_ch;
+	geo->num_lun = src->num_lun;
+	geo->all_luns = geo->num_ch * geo->num_lun;
+
+	geo->num_chk = le16_to_cpu(src->num_chk);
+
+	geo->csecs = le16_to_cpu(src->csecs);
+	geo->sos = le16_to_cpu(src->sos);
+
+	pg_per_blk = le16_to_cpu(src->num_pg);
+	sec_per_pg = le16_to_cpu(src->fpg_sz) / geo->csecs;
+	sec_per_pl = sec_per_pg * src->num_pln;
+	geo->clba = sec_per_pl * pg_per_blk;
+
+	geo->all_chunks = geo->all_luns * geo->num_chk;
+	geo->total_secs = geo->clba * geo->all_chunks;
+
+	geo->ws_min = sec_per_pg;
+	geo->ws_opt = sec_per_pg;
+	geo->mw_cunits = geo->ws_opt << 3;	/* default to MLC safe values */
+
+	/* Do not impose values for maximum number of open blocks as it is
+	 * unspecified in 1.2. Users of 1.2 must be aware of this and eventually
+	 * specify these values through a quirk if restrictions apply.
+	 */
+	geo->maxoc = geo->all_luns * geo->num_chk;
+	geo->maxocpu = geo->num_chk;
+
+	geo->mccap = le32_to_cpu(src->mccap);
+
+	geo->trdt = le32_to_cpu(src->trdt);
+	geo->trdm = le32_to_cpu(src->trdm);
+	geo->tprt = le32_to_cpu(src->tprt);
+	geo->tprm = le32_to_cpu(src->tprm);
+	geo->tbet = le32_to_cpu(src->tbet);
+	geo->tbem = le32_to_cpu(src->tbem);
+
+	/* 1.2 compatibility */
+	geo->vmnt = id->vmnt;
+	geo->cap = le32_to_cpu(id->cap);
+	geo->dom = le32_to_cpu(id->dom);
+
+	geo->mtype = src->mtype;
+	geo->fmtype = src->fmtype;
+
+	geo->cpar = le16_to_cpu(src->cpar);
+	geo->mpos = le32_to_cpu(src->mpos);
+
+	geo->pln_mode = NVM_PLANE_SINGLE;
+
+	if (geo->mpos & 0x020202) {
+		geo->pln_mode = NVM_PLANE_DOUBLE;
+		geo->ws_opt <<= 1;
+	} else if (geo->mpos & 0x040404) {
+		geo->pln_mode = NVM_PLANE_QUAD;
+		geo->ws_opt <<= 2;
+	}
+
+	geo->num_pln = src->num_pln;
+	geo->num_pg = le16_to_cpu(src->num_pg);
+	geo->fpg_sz = le16_to_cpu(src->fpg_sz);
+
+	nvme_nvm_set_addr_12((struct nvm_addrf_12 *)&geo->addrf, &id->ppaf);
+
+	return 0;
+}
+
+static void nvme_nvm_set_addr_20(struct nvm_addrf *dst,
+				 struct nvme_nvm_id20_addrf *src)
+{
+	dst->ch_len = src->grp_len;
+	dst->lun_len = src->pu_len;
+	dst->chk_len = src->chk_len;
+	dst->sec_len = src->lba_len;
+
+	dst->sec_offset = 0;
+	dst->chk_offset = dst->sec_len;
+	dst->lun_offset = dst->chk_offset + dst->chk_len;
+	dst->ch_offset = dst->lun_offset + dst->lun_len;
+
+	dst->ch_mask = ((1ULL << dst->ch_len) - 1) << dst->ch_offset;
+	dst->lun_mask = ((1ULL << dst->lun_len) - 1) << dst->lun_offset;
+	dst->chk_mask = ((1ULL << dst->chk_len) - 1) << dst->chk_offset;
+	dst->sec_mask = ((1ULL << dst->sec_len) - 1) << dst->sec_offset;
+}
+
+static int nvme_nvm_setup_20(struct nvme_nvm_id20 *id,
+			     struct nvm_geo *geo)
+{
+	geo->major_ver_id = id->mjr;
+	geo->minor_ver_id = id->mnr;
+
+	/* Set compacted version for upper layers */
+	geo->version = NVM_OCSSD_SPEC_20;
+
+	geo->num_ch = le16_to_cpu(id->num_grp);
+	geo->num_lun = le16_to_cpu(id->num_pu);
+	geo->all_luns = geo->num_ch * geo->num_lun;
+
+	geo->num_chk = le32_to_cpu(id->num_chk);
+	geo->clba = le32_to_cpu(id->clba);
+
+	geo->all_chunks = geo->all_luns * geo->num_chk;
+	geo->total_secs = geo->clba * geo->all_chunks;
+
+	geo->ws_min = le32_to_cpu(id->ws_min);
+	geo->ws_opt = le32_to_cpu(id->ws_opt);
+	geo->mw_cunits = le32_to_cpu(id->mw_cunits);
+	geo->maxoc = le32_to_cpu(id->maxoc);
+	geo->maxocpu = le32_to_cpu(id->maxocpu);
+
+	geo->trdt = le32_to_cpu(id->trdt);
+	geo->trdm = le32_to_cpu(id->trdm);
+	geo->tprt = le32_to_cpu(id->twrt);
+	geo->tprm = le32_to_cpu(id->twrm);
+	geo->tbet = le32_to_cpu(id->tcrst);
+	geo->tbem = le32_to_cpu(id->tcrsm);
+
+	nvme_nvm_set_addr_20(&geo->addrf, &id->lbaf);
+
+	return 0;
+}
+
+static int nvme_nvm_identity(struct nvm_dev *nvmdev)
+{
+	struct nvme_ns *ns = nvmdev->q->queuedata;
+	struct nvme_nvm_id12 *id;
+	struct nvme_nvm_command c = {};
+	int ret;
+
+	c.identity.opcode = nvme_nvm_admin_identity;
+	c.identity.nsid = cpu_to_le32(ns->head->ns_id);
+
+	id = kmalloc(sizeof(struct nvme_nvm_id12), GFP_KERNEL);
+	if (!id)
+		return -ENOMEM;
+
+	ret = nvme_submit_sync_cmd(ns->ctrl->admin_q, (struct nvme_command *)&c,
+				id, sizeof(struct nvme_nvm_id12));
+	if (ret) {
+		ret = -EIO;
+		goto out;
+	}
+
+	/*
+	 * The 1.2 and 2.0 specifications share the first byte in their geometry
+	 * command to make it possible to know what version a device implements.
+	 */
+	switch (id->ver_id) {
+	case 1:
+		ret = nvme_nvm_setup_12(id, &nvmdev->geo);
+		break;
+	case 2:
+		ret = nvme_nvm_setup_20((struct nvme_nvm_id20 *)id,
+							&nvmdev->geo);
+		break;
+	default:
+		dev_err(ns->ctrl->device, "OCSSD revision not supported (%d)\n",
+							id->ver_id);
+		ret = -EINVAL;
+	}
+
+out:
+	kfree(id);
+	return ret;
+}
+
+static int nvme_nvm_get_bb_tbl(struct nvm_dev *nvmdev, struct ppa_addr ppa,
+								u8 *blks)
+{
+	struct request_queue *q = nvmdev->q;
+	struct nvm_geo *geo = &nvmdev->geo;
+	struct nvme_ns *ns = q->queuedata;
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct nvme_nvm_command c = {};
+	struct nvme_nvm_bb_tbl *bb_tbl;
+	int nr_blks = geo->num_chk * geo->num_pln;
+	int tblsz = sizeof(struct nvme_nvm_bb_tbl) + nr_blks;
+	int ret = 0;
+
+	c.get_bb.opcode = nvme_nvm_admin_get_bb_tbl;
+	c.get_bb.nsid = cpu_to_le32(ns->head->ns_id);
+	c.get_bb.spba = cpu_to_le64(ppa.ppa);
+
+	bb_tbl = kzalloc(tblsz, GFP_KERNEL);
+	if (!bb_tbl)
+		return -ENOMEM;
+
+	ret = nvme_submit_sync_cmd(ctrl->admin_q, (struct nvme_command *)&c,
+								bb_tbl, tblsz);
+	if (ret) {
+		dev_err(ctrl->device, "get bad block table failed (%d)\n", ret);
+		ret = -EIO;
+		goto out;
+	}
+
+	if (bb_tbl->tblid[0] != 'B' || bb_tbl->tblid[1] != 'B' ||
+		bb_tbl->tblid[2] != 'L' || bb_tbl->tblid[3] != 'T') {
+		dev_err(ctrl->device, "bbt format mismatch\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (le16_to_cpu(bb_tbl->verid) != 1) {
+		ret = -EINVAL;
+		dev_err(ctrl->device, "bbt version not supported\n");
+		goto out;
+	}
+
+	if (le32_to_cpu(bb_tbl->tblks) != nr_blks) {
+		ret = -EINVAL;
+		dev_err(ctrl->device,
+				"bbt unsuspected blocks returned (%u!=%u)",
+				le32_to_cpu(bb_tbl->tblks), nr_blks);
+		goto out;
+	}
+
+	memcpy(blks, bb_tbl->blk, geo->num_chk * geo->num_pln);
+out:
+	kfree(bb_tbl);
+	return ret;
+}
+
+static int nvme_nvm_set_bb_tbl(struct nvm_dev *nvmdev, struct ppa_addr *ppas,
+							int nr_ppas, int type)
+{
+	struct nvme_ns *ns = nvmdev->q->queuedata;
+	struct nvme_nvm_command c = {};
+	int ret = 0;
+
+	c.set_bb.opcode = nvme_nvm_admin_set_bb_tbl;
+	c.set_bb.nsid = cpu_to_le32(ns->head->ns_id);
+	c.set_bb.spba = cpu_to_le64(ppas->ppa);
+	c.set_bb.nlb = cpu_to_le16(nr_ppas - 1);
+	c.set_bb.value = type;
+
+	ret = nvme_submit_sync_cmd(ns->ctrl->admin_q, (struct nvme_command *)&c,
+								NULL, 0);
+	if (ret)
+		dev_err(ns->ctrl->device, "set bad block table failed (%d)\n",
+									ret);
+	return ret;
+}
+
+/*
+ * Expect the lba in device format
+ */
+static int nvme_nvm_get_chk_meta(struct nvm_dev *ndev,
+				 struct nvm_chk_meta *meta,
+				 sector_t slba, int nchks)
+{
+	struct nvm_geo *geo = &ndev->geo;
+	struct nvme_ns *ns = ndev->q->queuedata;
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct nvme_nvm_chk_meta *dev_meta = (struct nvme_nvm_chk_meta *)meta;
+	struct ppa_addr ppa;
+	size_t left = nchks * sizeof(struct nvme_nvm_chk_meta);
+	size_t log_pos, offset, len;
+	int ret, i, max_len;
+
+	/*
+	 * limit requests to maximum 256K to avoid issuing arbitrary large
+	 * requests when the device does not specific a maximum transfer size.
+	 */
+	max_len = min_t(unsigned int, ctrl->max_hw_sectors << 9, 256 * 1024);
+
+	/* Normalize lba address space to obtain log offset */
+	ppa.ppa = slba;
+	ppa = dev_to_generic_addr(ndev, ppa);
+
+	log_pos = ppa.m.chk;
+	log_pos += ppa.m.pu * geo->num_chk;
+	log_pos += ppa.m.grp * geo->num_lun * geo->num_chk;
+
+	offset = log_pos * sizeof(struct nvme_nvm_chk_meta);
+
+	while (left) {
+		len = min_t(unsigned int, left, max_len);
+
+		ret = nvme_get_log(ctrl, ns->head->ns_id,
+				NVME_NVM_LOG_REPORT_CHUNK, 0, dev_meta, len,
+				offset);
+		if (ret) {
+			dev_err(ctrl->device, "Get REPORT CHUNK log error\n");
+			break;
+		}
+
+		for (i = 0; i < len; i += sizeof(struct nvme_nvm_chk_meta)) {
+			meta->state = dev_meta->state;
+			meta->type = dev_meta->type;
+			meta->wi = dev_meta->wi;
+			meta->slba = le64_to_cpu(dev_meta->slba);
+			meta->cnlb = le64_to_cpu(dev_meta->cnlb);
+			meta->wp = le64_to_cpu(dev_meta->wp);
+
+			meta++;
+			dev_meta++;
+		}
+
+		offset += len;
+		left -= len;
+	}
+
+	return ret;
+}
+
+static inline void nvme_nvm_rqtocmd(struct nvm_rq *rqd, struct nvme_ns *ns,
+				    struct nvme_nvm_command *c)
+{
+	c->ph_rw.opcode = rqd->opcode;
+	c->ph_rw.nsid = cpu_to_le32(ns->head->ns_id);
+	c->ph_rw.spba = cpu_to_le64(rqd->ppa_addr.ppa);
+	c->ph_rw.metadata = cpu_to_le64(rqd->dma_meta_list);
+	c->ph_rw.control = cpu_to_le16(rqd->flags);
+	c->ph_rw.length = cpu_to_le16(rqd->nr_ppas - 1);
+}
+
+static void nvme_nvm_end_io(struct request *rq, blk_status_t status)
+{
+	struct nvm_rq *rqd = rq->end_io_data;
+
+	rqd->ppa_status = le64_to_cpu(nvme_req(rq)->result.u64);
+	rqd->error = nvme_req(rq)->status;
+	nvm_end_io(rqd);
+
+	kfree(nvme_req(rq)->cmd);
+	blk_mq_free_request(rq);
+}
+
+static struct request *nvme_nvm_alloc_request(struct request_queue *q,
+					      struct nvm_rq *rqd,
+					      struct nvme_nvm_command *cmd)
+{
+	struct nvme_ns *ns = q->queuedata;
+	struct request *rq;
+
+	nvme_nvm_rqtocmd(rqd, ns, cmd);
+
+	rq = nvme_alloc_request(q, (struct nvme_command *)cmd, 0, NVME_QID_ANY);
+	if (IS_ERR(rq))
+		return rq;
+
+	rq->cmd_flags &= ~REQ_FAILFAST_DRIVER;
+
+	if (rqd->bio)
+		blk_init_request_from_bio(rq, rqd->bio);
+	else
+		rq->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
+
+	return rq;
+}
+
+static int nvme_nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
+{
+	struct request_queue *q = dev->q;
+	struct nvme_nvm_command *cmd;
+	struct request *rq;
+
+	cmd = kzalloc(sizeof(struct nvme_nvm_command), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	rq = nvme_nvm_alloc_request(q, rqd, cmd);
+	if (IS_ERR(rq)) {
+		kfree(cmd);
+		return PTR_ERR(rq);
+	}
+
+	rq->end_io_data = rqd;
+
+	blk_execute_rq_nowait(q, NULL, rq, 0, nvme_nvm_end_io);
+
+	return 0;
+}
+
+static int nvme_nvm_submit_io_sync(struct nvm_dev *dev, struct nvm_rq *rqd)
+{
+	struct request_queue *q = dev->q;
+	struct request *rq;
+	struct nvme_nvm_command cmd;
+	int ret = 0;
+
+	memset(&cmd, 0, sizeof(struct nvme_nvm_command));
+
+	rq = nvme_nvm_alloc_request(q, rqd, &cmd);
+	if (IS_ERR(rq))
+		return PTR_ERR(rq);
+
+	/* I/Os can fail and the error is signaled through rqd. Callers must
+	 * handle the error accordingly.
+	 */
+	blk_execute_rq(q, NULL, rq, 0);
+	if (nvme_req(rq)->flags & NVME_REQ_CANCELLED)
+		ret = -EINTR;
+
+	rqd->ppa_status = le64_to_cpu(nvme_req(rq)->result.u64);
+	rqd->error = nvme_req(rq)->status;
+
+	blk_mq_free_request(rq);
+
+	return ret;
+}
+
+static void *nvme_nvm_create_dma_pool(struct nvm_dev *nvmdev, char *name)
+{
+	struct nvme_ns *ns = nvmdev->q->queuedata;
+
+	return dma_pool_create(name, ns->ctrl->dev, PAGE_SIZE, PAGE_SIZE, 0);
+}
+
+static void nvme_nvm_destroy_dma_pool(void *pool)
+{
+	struct dma_pool *dma_pool = pool;
+
+	dma_pool_destroy(dma_pool);
+}
+
+static void *nvme_nvm_dev_dma_alloc(struct nvm_dev *dev, void *pool,
+				    gfp_t mem_flags, dma_addr_t *dma_handler)
+{
+	return dma_pool_alloc(pool, mem_flags, dma_handler);
+}
+
+static void nvme_nvm_dev_dma_free(void *pool, void *addr,
+							dma_addr_t dma_handler)
+{
+	dma_pool_free(pool, addr, dma_handler);
+}
+
+static struct nvm_dev_ops nvme_nvm_dev_ops = {
+	.identity		= nvme_nvm_identity,
+
+	.get_bb_tbl		= nvme_nvm_get_bb_tbl,
+	.set_bb_tbl		= nvme_nvm_set_bb_tbl,
+
+	.get_chk_meta		= nvme_nvm_get_chk_meta,
+
+	.submit_io		= nvme_nvm_submit_io,
+	.submit_io_sync		= nvme_nvm_submit_io_sync,
+
+	.create_dma_pool	= nvme_nvm_create_dma_pool,
+	.destroy_dma_pool	= nvme_nvm_destroy_dma_pool,
+	.dev_dma_alloc		= nvme_nvm_dev_dma_alloc,
+	.dev_dma_free		= nvme_nvm_dev_dma_free,
+};
+
+static int nvme_nvm_submit_user_cmd(struct request_queue *q,
+				struct nvme_ns *ns,
+				struct nvme_nvm_command *vcmd,
+				void __user *ubuf, unsigned int bufflen,
+				void __user *meta_buf, unsigned int meta_len,
+				void __user *ppa_buf, unsigned int ppa_len,
+				u32 *result, u64 *status, unsigned int timeout)
+{
+	bool write = nvme_is_write((struct nvme_command *)vcmd);
+	struct nvm_dev *dev = ns->ndev;
+	struct gendisk *disk = ns->disk;
+	struct request *rq;
+	struct bio *bio = NULL;
+	__le64 *ppa_list = NULL;
+	dma_addr_t ppa_dma;
+	__le64 *metadata = NULL;
+	dma_addr_t metadata_dma;
+	DECLARE_COMPLETION_ONSTACK(wait);
+	int ret = 0;
+
+	rq = nvme_alloc_request(q, (struct nvme_command *)vcmd, 0,
+			NVME_QID_ANY);
+	if (IS_ERR(rq)) {
+		ret = -ENOMEM;
+		goto err_cmd;
+	}
+
+	rq->timeout = timeout ? timeout : ADMIN_TIMEOUT;
+
+	if (ppa_buf && ppa_len) {
+		ppa_list = dma_pool_alloc(dev->dma_pool, GFP_KERNEL, &ppa_dma);
+		if (!ppa_list) {
+			ret = -ENOMEM;
+			goto err_rq;
+		}
+		if (copy_from_user(ppa_list, (void __user *)ppa_buf,
+						sizeof(u64) * (ppa_len + 1))) {
+			ret = -EFAULT;
+			goto err_ppa;
+		}
+		vcmd->ph_rw.spba = cpu_to_le64(ppa_dma);
+	} else {
+		vcmd->ph_rw.spba = cpu_to_le64((uintptr_t)ppa_buf);
+	}
+
+	if (ubuf && bufflen) {
+		ret = blk_rq_map_user(q, rq, NULL, ubuf, bufflen, GFP_KERNEL);
+		if (ret)
+			goto err_ppa;
+		bio = rq->bio;
+
+		if (meta_buf && meta_len) {
+			metadata = dma_pool_alloc(dev->dma_pool, GFP_KERNEL,
+								&metadata_dma);
+			if (!metadata) {
+				ret = -ENOMEM;
+				goto err_map;
+			}
+
+			if (write) {
+				if (copy_from_user(metadata,
+						(void __user *)meta_buf,
+						meta_len)) {
+					ret = -EFAULT;
+					goto err_meta;
+				}
+			}
+			vcmd->ph_rw.metadata = cpu_to_le64(metadata_dma);
+		}
+
+		bio->bi_disk = disk;
+	}
+
+	blk_execute_rq(q, NULL, rq, 0);
+
+	if (nvme_req(rq)->flags & NVME_REQ_CANCELLED)
+		ret = -EINTR;
+	else if (nvme_req(rq)->status & 0x7ff)
+		ret = -EIO;
+	if (result)
+		*result = nvme_req(rq)->status & 0x7ff;
+	if (status)
+		*status = le64_to_cpu(nvme_req(rq)->result.u64);
+
+	if (metadata && !ret && !write) {
+		if (copy_to_user(meta_buf, (void *)metadata, meta_len))
+			ret = -EFAULT;
+	}
+err_meta:
+	if (meta_buf && meta_len)
+		dma_pool_free(dev->dma_pool, metadata, metadata_dma);
+err_map:
+	if (bio)
+		blk_rq_unmap_user(bio);
+err_ppa:
+	if (ppa_buf && ppa_len)
+		dma_pool_free(dev->dma_pool, ppa_list, ppa_dma);
+err_rq:
+	blk_mq_free_request(rq);
+err_cmd:
+	return ret;
+}
+
+static int nvme_nvm_submit_vio(struct nvme_ns *ns,
+					struct nvm_user_vio __user *uvio)
+{
+	struct nvm_user_vio vio;
+	struct nvme_nvm_command c;
+	unsigned int length;
+	int ret;
+
+	if (copy_from_user(&vio, uvio, sizeof(vio)))
+		return -EFAULT;
+	if (vio.flags)
+		return -EINVAL;
+
+	memset(&c, 0, sizeof(c));
+	c.ph_rw.opcode = vio.opcode;
+	c.ph_rw.nsid = cpu_to_le32(ns->head->ns_id);
+	c.ph_rw.control = cpu_to_le16(vio.control);
+	c.ph_rw.length = cpu_to_le16(vio.nppas);
+
+	length = (vio.nppas + 1) << ns->lba_shift;
+
+	ret = nvme_nvm_submit_user_cmd(ns->queue, ns, &c,
+			(void __user *)(uintptr_t)vio.addr, length,
+			(void __user *)(uintptr_t)vio.metadata,
+							vio.metadata_len,
+			(void __user *)(uintptr_t)vio.ppa_list, vio.nppas,
+			&vio.result, &vio.status, 0);
+
+	if (ret && copy_to_user(uvio, &vio, sizeof(vio)))
+		return -EFAULT;
+
+	return ret;
+}
+
+static int nvme_nvm_user_vcmd(struct nvme_ns *ns, int admin,
+					struct nvm_passthru_vio __user *uvcmd)
+{
+	struct nvm_passthru_vio vcmd;
+	struct nvme_nvm_command c;
+	struct request_queue *q;
+	unsigned int timeout = 0;
+	int ret;
+
+	if (copy_from_user(&vcmd, uvcmd, sizeof(vcmd)))
+		return -EFAULT;
+	if ((vcmd.opcode != 0xF2) && (!capable(CAP_SYS_ADMIN)))
+		return -EACCES;
+	if (vcmd.flags)
+		return -EINVAL;
+
+	memset(&c, 0, sizeof(c));
+	c.common.opcode = vcmd.opcode;
+	c.common.nsid = cpu_to_le32(ns->head->ns_id);
+	c.common.cdw2[0] = cpu_to_le32(vcmd.cdw2);
+	c.common.cdw2[1] = cpu_to_le32(vcmd.cdw3);
+	/* cdw11-12 */
+	c.ph_rw.length = cpu_to_le16(vcmd.nppas);
+	c.ph_rw.control  = cpu_to_le16(vcmd.control);
+	c.common.cdw10[3] = cpu_to_le32(vcmd.cdw13);
+	c.common.cdw10[4] = cpu_to_le32(vcmd.cdw14);
+	c.common.cdw10[5] = cpu_to_le32(vcmd.cdw15);
+
+	if (vcmd.timeout_ms)
+		timeout = msecs_to_jiffies(vcmd.timeout_ms);
+
+	q = admin ? ns->ctrl->admin_q : ns->queue;
+
+	ret = nvme_nvm_submit_user_cmd(q, ns,
+			(struct nvme_nvm_command *)&c,
+			(void __user *)(uintptr_t)vcmd.addr, vcmd.data_len,
+			(void __user *)(uintptr_t)vcmd.metadata,
+							vcmd.metadata_len,
+			(void __user *)(uintptr_t)vcmd.ppa_list, vcmd.nppas,
+			&vcmd.result, &vcmd.status, timeout);
+
+	if (ret && copy_to_user(uvcmd, &vcmd, sizeof(vcmd)))
+		return -EFAULT;
+
+	return ret;
+}
+
+int nvme_nvm_ioctl(struct nvme_ns *ns, unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case NVME_NVM_IOCTL_ADMIN_VIO:
+		return nvme_nvm_user_vcmd(ns, 1, (void __user *)arg);
+	case NVME_NVM_IOCTL_IO_VIO:
+		return nvme_nvm_user_vcmd(ns, 0, (void __user *)arg);
+	case NVME_NVM_IOCTL_SUBMIT_VIO:
+		return nvme_nvm_submit_vio(ns, (void __user *)arg);
+	default:
+		return -ENOTTY;
+	}
+}
+
+void nvme_nvm_update_nvm_info(struct nvme_ns *ns)
+{
+	struct nvm_dev *ndev = ns->ndev;
+	struct nvm_geo *geo = &ndev->geo;
+
+	if (geo->version == NVM_OCSSD_SPEC_12)
+		return;
+
+	geo->csecs = 1 << ns->lba_shift;
+	geo->sos = ns->ms;
+}
+
+int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node)
+{
+	struct request_queue *q = ns->queue;
+	struct nvm_dev *dev;
+
+	_nvme_nvm_check_size();
+
+	dev = nvm_alloc_dev(node);
+	if (!dev)
+		return -ENOMEM;
+
+	dev->q = q;
+	memcpy(dev->name, disk_name, DISK_NAME_LEN);
+	dev->ops = &nvme_nvm_dev_ops;
+	dev->private_data = ns;
+	ns->ndev = dev;
+
+	return nvm_register(dev);
+}
+
+void nvme_nvm_unregister(struct nvme_ns *ns)
+{
+	nvm_unregister(ns->ndev);
+}
+
+static ssize_t nvm_dev_attr_show(struct device *dev,
+		struct device_attribute *dattr, char *page)
+{
+	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
+	struct nvm_dev *ndev = ns->ndev;
+	struct nvm_geo *geo = &ndev->geo;
+	struct attribute *attr;
+
+	if (!ndev)
+		return 0;
+
+	attr = &dattr->attr;
+
+	if (strcmp(attr->name, "version") == 0) {
+		if (geo->major_ver_id == 1)
+			return scnprintf(page, PAGE_SIZE, "%u\n",
+						geo->major_ver_id);
+		else
+			return scnprintf(page, PAGE_SIZE, "%u.%u\n",
+						geo->major_ver_id,
+						geo->minor_ver_id);
+	} else if (strcmp(attr->name, "capabilities") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->cap);
+	} else if (strcmp(attr->name, "read_typ") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->trdt);
+	} else if (strcmp(attr->name, "read_max") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->trdm);
+	} else {
+		return scnprintf(page,
+				 PAGE_SIZE,
+				 "Unhandled attr(%s) in `%s`\n",
+				 attr->name, __func__);
+	}
+}
+
+static ssize_t nvm_dev_attr_show_ppaf(struct nvm_addrf_12 *ppaf, char *page)
+{
+	return scnprintf(page, PAGE_SIZE,
+		"0x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+				ppaf->ch_offset, ppaf->ch_len,
+				ppaf->lun_offset, ppaf->lun_len,
+				ppaf->pln_offset, ppaf->pln_len,
+				ppaf->blk_offset, ppaf->blk_len,
+				ppaf->pg_offset, ppaf->pg_len,
+				ppaf->sec_offset, ppaf->sec_len);
+}
+
+static ssize_t nvm_dev_attr_show_12(struct device *dev,
+		struct device_attribute *dattr, char *page)
+{
+	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
+	struct nvm_dev *ndev = ns->ndev;
+	struct nvm_geo *geo = &ndev->geo;
+	struct attribute *attr;
+
+	if (!ndev)
+		return 0;
+
+	attr = &dattr->attr;
+
+	if (strcmp(attr->name, "vendor_opcode") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->vmnt);
+	} else if (strcmp(attr->name, "device_mode") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->dom);
+	/* kept for compatibility */
+	} else if (strcmp(attr->name, "media_manager") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%s\n", "gennvm");
+	} else if (strcmp(attr->name, "ppa_format") == 0) {
+		return nvm_dev_attr_show_ppaf((void *)&geo->addrf, page);
+	} else if (strcmp(attr->name, "media_type") == 0) {	/* u8 */
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->mtype);
+	} else if (strcmp(attr->name, "flash_media_type") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->fmtype);
+	} else if (strcmp(attr->name, "num_channels") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_ch);
+	} else if (strcmp(attr->name, "num_luns") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_lun);
+	} else if (strcmp(attr->name, "num_planes") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_pln);
+	} else if (strcmp(attr->name, "num_blocks") == 0) {	/* u16 */
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_chk);
+	} else if (strcmp(attr->name, "num_pages") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_pg);
+	} else if (strcmp(attr->name, "page_size") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->fpg_sz);
+	} else if (strcmp(attr->name, "hw_sector_size") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->csecs);
+	} else if (strcmp(attr->name, "oob_sector_size") == 0) {/* u32 */
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->sos);
+	} else if (strcmp(attr->name, "prog_typ") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tprt);
+	} else if (strcmp(attr->name, "prog_max") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tprm);
+	} else if (strcmp(attr->name, "erase_typ") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tbet);
+	} else if (strcmp(attr->name, "erase_max") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tbem);
+	} else if (strcmp(attr->name, "multiplane_modes") == 0) {
+		return scnprintf(page, PAGE_SIZE, "0x%08x\n", geo->mpos);
+	} else if (strcmp(attr->name, "media_capabilities") == 0) {
+		return scnprintf(page, PAGE_SIZE, "0x%08x\n", geo->mccap);
+	} else if (strcmp(attr->name, "max_phys_secs") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", NVM_MAX_VLBA);
+	} else {
+		return scnprintf(page, PAGE_SIZE,
+			"Unhandled attr(%s) in `%s`\n",
+			attr->name, __func__);
+	}
+}
+
+static ssize_t nvm_dev_attr_show_20(struct device *dev,
+		struct device_attribute *dattr, char *page)
+{
+	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
+	struct nvm_dev *ndev = ns->ndev;
+	struct nvm_geo *geo = &ndev->geo;
+	struct attribute *attr;
+
+	if (!ndev)
+		return 0;
+
+	attr = &dattr->attr;
+
+	if (strcmp(attr->name, "groups") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_ch);
+	} else if (strcmp(attr->name, "punits") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_lun);
+	} else if (strcmp(attr->name, "chunks") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->num_chk);
+	} else if (strcmp(attr->name, "clba") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->clba);
+	} else if (strcmp(attr->name, "ws_min") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->ws_min);
+	} else if (strcmp(attr->name, "ws_opt") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->ws_opt);
+	} else if (strcmp(attr->name, "maxoc") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->maxoc);
+	} else if (strcmp(attr->name, "maxocpu") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->maxocpu);
+	} else if (strcmp(attr->name, "mw_cunits") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->mw_cunits);
+	} else if (strcmp(attr->name, "write_typ") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tprt);
+	} else if (strcmp(attr->name, "write_max") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tprm);
+	} else if (strcmp(attr->name, "reset_typ") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tbet);
+	} else if (strcmp(attr->name, "reset_max") == 0) {
+		return scnprintf(page, PAGE_SIZE, "%u\n", geo->tbem);
+	} else {
+		return scnprintf(page, PAGE_SIZE,
+			"Unhandled attr(%s) in `%s`\n",
+			attr->name, __func__);
+	}
+}
+
+#define NVM_DEV_ATTR_RO(_name)					\
+	DEVICE_ATTR(_name, S_IRUGO, nvm_dev_attr_show, NULL)
+#define NVM_DEV_ATTR_12_RO(_name)					\
+	DEVICE_ATTR(_name, S_IRUGO, nvm_dev_attr_show_12, NULL)
+#define NVM_DEV_ATTR_20_RO(_name)					\
+	DEVICE_ATTR(_name, S_IRUGO, nvm_dev_attr_show_20, NULL)
+
+/* general attributes */
+static NVM_DEV_ATTR_RO(version);
+static NVM_DEV_ATTR_RO(capabilities);
+
+static NVM_DEV_ATTR_RO(read_typ);
+static NVM_DEV_ATTR_RO(read_max);
+
+/* 1.2 values */
+static NVM_DEV_ATTR_12_RO(vendor_opcode);
+static NVM_DEV_ATTR_12_RO(device_mode);
+static NVM_DEV_ATTR_12_RO(ppa_format);
+static NVM_DEV_ATTR_12_RO(media_manager);
+static NVM_DEV_ATTR_12_RO(media_type);
+static NVM_DEV_ATTR_12_RO(flash_media_type);
+static NVM_DEV_ATTR_12_RO(num_channels);
+static NVM_DEV_ATTR_12_RO(num_luns);
+static NVM_DEV_ATTR_12_RO(num_planes);
+static NVM_DEV_ATTR_12_RO(num_blocks);
+static NVM_DEV_ATTR_12_RO(num_pages);
+static NVM_DEV_ATTR_12_RO(page_size);
+static NVM_DEV_ATTR_12_RO(hw_sector_size);
+static NVM_DEV_ATTR_12_RO(oob_sector_size);
+static NVM_DEV_ATTR_12_RO(prog_typ);
+static NVM_DEV_ATTR_12_RO(prog_max);
+static NVM_DEV_ATTR_12_RO(erase_typ);
+static NVM_DEV_ATTR_12_RO(erase_max);
+static NVM_DEV_ATTR_12_RO(multiplane_modes);
+static NVM_DEV_ATTR_12_RO(media_capabilities);
+static NVM_DEV_ATTR_12_RO(max_phys_secs);
+
+/* 2.0 values */
+static NVM_DEV_ATTR_20_RO(groups);
+static NVM_DEV_ATTR_20_RO(punits);
+static NVM_DEV_ATTR_20_RO(chunks);
+static NVM_DEV_ATTR_20_RO(clba);
+static NVM_DEV_ATTR_20_RO(ws_min);
+static NVM_DEV_ATTR_20_RO(ws_opt);
+static NVM_DEV_ATTR_20_RO(maxoc);
+static NVM_DEV_ATTR_20_RO(maxocpu);
+static NVM_DEV_ATTR_20_RO(mw_cunits);
+static NVM_DEV_ATTR_20_RO(write_typ);
+static NVM_DEV_ATTR_20_RO(write_max);
+static NVM_DEV_ATTR_20_RO(reset_typ);
+static NVM_DEV_ATTR_20_RO(reset_max);
+
+static struct attribute *nvm_dev_attrs[] = {
+	/* version agnostic attrs */
+	&dev_attr_version.attr,
+	&dev_attr_capabilities.attr,
+	&dev_attr_read_typ.attr,
+	&dev_attr_read_max.attr,
+
+	/* 1.2 attrs */
+	&dev_attr_vendor_opcode.attr,
+	&dev_attr_device_mode.attr,
+	&dev_attr_media_manager.attr,
+	&dev_attr_ppa_format.attr,
+	&dev_attr_media_type.attr,
+	&dev_attr_flash_media_type.attr,
+	&dev_attr_num_channels.attr,
+	&dev_attr_num_luns.attr,
+	&dev_attr_num_planes.attr,
+	&dev_attr_num_blocks.attr,
+	&dev_attr_num_pages.attr,
+	&dev_attr_page_size.attr,
+	&dev_attr_hw_sector_size.attr,
+	&dev_attr_oob_sector_size.attr,
+	&dev_attr_prog_typ.attr,
+	&dev_attr_prog_max.attr,
+	&dev_attr_erase_typ.attr,
+	&dev_attr_erase_max.attr,
+	&dev_attr_multiplane_modes.attr,
+	&dev_attr_media_capabilities.attr,
+	&dev_attr_max_phys_secs.attr,
+
+	/* 2.0 attrs */
+	&dev_attr_groups.attr,
+	&dev_attr_punits.attr,
+	&dev_attr_chunks.attr,
+	&dev_attr_clba.attr,
+	&dev_attr_ws_min.attr,
+	&dev_attr_ws_opt.attr,
+	&dev_attr_maxoc.attr,
+	&dev_attr_maxocpu.attr,
+	&dev_attr_mw_cunits.attr,
+
+	&dev_attr_write_typ.attr,
+	&dev_attr_write_max.attr,
+	&dev_attr_reset_typ.attr,
+	&dev_attr_reset_max.attr,
+
+	NULL,
+};
+
+static umode_t nvm_dev_attrs_visible(struct kobject *kobj,
+				     struct attribute *attr, int index)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct gendisk *disk = dev_to_disk(dev);
+	struct nvme_ns *ns = disk->private_data;
+	struct nvm_dev *ndev = ns->ndev;
+	struct device_attribute *dev_attr =
+		container_of(attr, typeof(*dev_attr), attr);
+
+	if (!ndev)
+		return 0;
+
+	if (dev_attr->show == nvm_dev_attr_show)
+		return attr->mode;
+
+	switch (ndev->geo.major_ver_id) {
+	case 1:
+		if (dev_attr->show == nvm_dev_attr_show_12)
+			return attr->mode;
+		break;
+	case 2:
+		if (dev_attr->show == nvm_dev_attr_show_20)
+			return attr->mode;
+		break;
+	}
+
+	return 0;
+}
+
+const struct attribute_group nvme_nvm_attr_group = {
+	.name		= "lightnvm",
+	.attrs		= nvm_dev_attrs,
+	.is_visible	= nvm_dev_attrs_visible,
+};
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
new file mode 100644
index 000000000..022e03643
--- /dev/null
+++ b/drivers/nvme/host/multipath.c
@@ -0,0 +1,609 @@
+/*
+ * Copyright (c) 2017-2018 Christoph Hellwig.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/backing-dev.h>
+#include <linux/moduleparam.h>
+#include <trace/events/block.h>
+#include "nvme.h"
+
+static bool multipath = true;
+module_param(multipath, bool, 0444);
+MODULE_PARM_DESC(multipath,
+	"turn on native support for multiple controllers per subsystem");
+
+void nvme_mpath_unfreeze(struct nvme_subsystem *subsys)
+{
+	struct nvme_ns_head *h;
+
+	lockdep_assert_held(&subsys->lock);
+	list_for_each_entry(h, &subsys->nsheads, entry)
+		if (h->disk)
+			blk_mq_unfreeze_queue(h->disk->queue);
+}
+
+void nvme_mpath_wait_freeze(struct nvme_subsystem *subsys)
+{
+	struct nvme_ns_head *h;
+
+	lockdep_assert_held(&subsys->lock);
+	list_for_each_entry(h, &subsys->nsheads, entry)
+		if (h->disk)
+			blk_mq_freeze_queue_wait(h->disk->queue);
+}
+
+void nvme_mpath_start_freeze(struct nvme_subsystem *subsys)
+{
+	struct nvme_ns_head *h;
+
+	lockdep_assert_held(&subsys->lock);
+	list_for_each_entry(h, &subsys->nsheads, entry)
+		if (h->disk)
+			blk_freeze_queue_start(h->disk->queue);
+}
+
+/*
+ * If multipathing is enabled we need to always use the subsystem instance
+ * number for numbering our devices to avoid conflicts between subsystems that
+ * have multiple controllers and thus use the multipath-aware subsystem node
+ * and those that have a single controller and use the controller node
+ * directly.
+ */
+void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+			struct nvme_ctrl *ctrl, int *flags)
+{
+	if (!multipath) {
+		sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
+	} else if (ns->head->disk) {
+		sprintf(disk_name, "nvme%dc%dn%d", ctrl->subsys->instance,
+				ctrl->cntlid, ns->head->instance);
+		*flags = GENHD_FL_HIDDEN;
+	} else {
+		sprintf(disk_name, "nvme%dn%d", ctrl->subsys->instance,
+				ns->head->instance);
+	}
+}
+
+bool nvme_failover_req(struct request *req)
+{
+	struct nvme_ns *ns = req->q->queuedata;
+	u16 status = nvme_req(req)->status;
+	unsigned long flags;
+
+	switch (status & 0x7ff) {
+	case NVME_SC_ANA_TRANSITION:
+	case NVME_SC_ANA_INACCESSIBLE:
+	case NVME_SC_ANA_PERSISTENT_LOSS:
+		/*
+		 * If we got back an ANA error we know the controller is alive,
+		 * but not ready to serve this namespaces.  The spec suggests
+		 * we should update our general state here, but due to the fact
+		 * that the admin and I/O queues are not serialized that is
+		 * fundamentally racy.  So instead just clear the current path,
+		 * mark the the path as pending and kick of a re-read of the ANA
+		 * log page ASAP.
+		 */
+		nvme_mpath_clear_current_path(ns);
+		if (ns->ctrl->ana_log_buf) {
+			set_bit(NVME_NS_ANA_PENDING, &ns->flags);
+			queue_work(nvme_wq, &ns->ctrl->ana_work);
+		}
+		break;
+	case NVME_SC_HOST_PATH_ERROR:
+		/*
+		 * Temporary transport disruption in talking to the controller.
+		 * Try to send on a new path.
+		 */
+		nvme_mpath_clear_current_path(ns);
+		break;
+	default:
+		/* This was a non-ANA error so follow the normal error path. */
+		return false;
+	}
+
+	spin_lock_irqsave(&ns->head->requeue_lock, flags);
+	blk_steal_bios(&ns->head->requeue_list, req);
+	spin_unlock_irqrestore(&ns->head->requeue_lock, flags);
+	blk_mq_end_request(req, 0);
+
+	kblockd_schedule_work(&ns->head->requeue_work);
+	return true;
+}
+
+void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl)
+{
+	struct nvme_ns *ns;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list) {
+		if (ns->head->disk)
+			kblockd_schedule_work(&ns->head->requeue_work);
+	}
+	up_read(&ctrl->namespaces_rwsem);
+}
+
+static const char *nvme_ana_state_names[] = {
+	[0]				= "invalid state",
+	[NVME_ANA_OPTIMIZED]		= "optimized",
+	[NVME_ANA_NONOPTIMIZED]		= "non-optimized",
+	[NVME_ANA_INACCESSIBLE]		= "inaccessible",
+	[NVME_ANA_PERSISTENT_LOSS]	= "persistent-loss",
+	[NVME_ANA_CHANGE]		= "change",
+};
+
+static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head)
+{
+	struct nvme_ns *ns, *fallback = NULL;
+
+	list_for_each_entry_rcu(ns, &head->list, siblings) {
+		if (ns->ctrl->state != NVME_CTRL_LIVE ||
+		    test_bit(NVME_NS_ANA_PENDING, &ns->flags))
+			continue;
+		switch (ns->ana_state) {
+		case NVME_ANA_OPTIMIZED:
+			rcu_assign_pointer(head->current_path, ns);
+			return ns;
+		case NVME_ANA_NONOPTIMIZED:
+			fallback = ns;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (fallback)
+		rcu_assign_pointer(head->current_path, fallback);
+	return fallback;
+}
+
+static inline bool nvme_path_is_optimized(struct nvme_ns *ns)
+{
+	return ns->ctrl->state == NVME_CTRL_LIVE &&
+		ns->ana_state == NVME_ANA_OPTIMIZED;
+}
+
+inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head)
+{
+	struct nvme_ns *ns = srcu_dereference(head->current_path, &head->srcu);
+
+	if (unlikely(!ns || !nvme_path_is_optimized(ns)))
+		ns = __nvme_find_path(head);
+	return ns;
+}
+
+static blk_qc_t nvme_ns_head_make_request(struct request_queue *q,
+		struct bio *bio)
+{
+	struct nvme_ns_head *head = q->queuedata;
+	struct device *dev = disk_to_dev(head->disk);
+	struct nvme_ns *ns;
+	blk_qc_t ret = BLK_QC_T_NONE;
+	int srcu_idx;
+
+	srcu_idx = srcu_read_lock(&head->srcu);
+	ns = nvme_find_path(head);
+	if (likely(ns)) {
+		bio->bi_disk = ns->disk;
+		bio->bi_opf |= REQ_NVME_MPATH;
+		trace_block_bio_remap(bio->bi_disk->queue, bio,
+				      disk_devt(ns->head->disk),
+				      bio->bi_iter.bi_sector);
+		ret = direct_make_request(bio);
+	} else if (!list_empty_careful(&head->list)) {
+		dev_warn_ratelimited(dev, "no path available - requeuing I/O\n");
+
+		spin_lock_irq(&head->requeue_lock);
+		bio_list_add(&head->requeue_list, bio);
+		spin_unlock_irq(&head->requeue_lock);
+	} else {
+		dev_warn_ratelimited(dev, "no path - failing I/O\n");
+
+		bio->bi_status = BLK_STS_IOERR;
+		bio_endio(bio);
+	}
+
+	srcu_read_unlock(&head->srcu, srcu_idx);
+	return ret;
+}
+
+static bool nvme_ns_head_poll(struct request_queue *q, blk_qc_t qc)
+{
+	struct nvme_ns_head *head = q->queuedata;
+	struct nvme_ns *ns;
+	bool found = false;
+	int srcu_idx;
+
+	srcu_idx = srcu_read_lock(&head->srcu);
+	ns = srcu_dereference(head->current_path, &head->srcu);
+	if (likely(ns && nvme_path_is_optimized(ns)))
+		found = ns->queue->poll_fn(q, qc);
+	srcu_read_unlock(&head->srcu, srcu_idx);
+	return found;
+}
+
+static void nvme_requeue_work(struct work_struct *work)
+{
+	struct nvme_ns_head *head =
+		container_of(work, struct nvme_ns_head, requeue_work);
+	struct bio *bio, *next;
+
+	spin_lock_irq(&head->requeue_lock);
+	next = bio_list_get(&head->requeue_list);
+	spin_unlock_irq(&head->requeue_lock);
+
+	while ((bio = next) != NULL) {
+		next = bio->bi_next;
+		bio->bi_next = NULL;
+
+		/*
+		 * Reset disk to the mpath node and resubmit to select a new
+		 * path.
+		 */
+		bio->bi_disk = head->disk;
+		generic_make_request(bio);
+	}
+}
+
+int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head)
+{
+	struct request_queue *q;
+	bool vwc = false;
+
+	mutex_init(&head->lock);
+	bio_list_init(&head->requeue_list);
+	spin_lock_init(&head->requeue_lock);
+	INIT_WORK(&head->requeue_work, nvme_requeue_work);
+
+	/*
+	 * Add a multipath node if the subsystems supports multiple controllers.
+	 * We also do this for private namespaces as the namespace sharing data could
+	 * change after a rescan.
+	 */
+	if (!(ctrl->subsys->cmic & (1 << 1)) || !multipath)
+		return 0;
+
+	q = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE, NULL);
+	if (!q)
+		goto out;
+	q->queuedata = head;
+	blk_queue_make_request(q, nvme_ns_head_make_request);
+	q->poll_fn = nvme_ns_head_poll;
+	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
+	/* set to a default value for 512 until disk is validated */
+	blk_queue_logical_block_size(q, 512);
+	blk_set_stacking_limits(&q->limits);
+
+	/* we need to propagate up the VMC settings */
+	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
+		vwc = true;
+	blk_queue_write_cache(q, vwc, vwc);
+
+	head->disk = alloc_disk(0);
+	if (!head->disk)
+		goto out_cleanup_queue;
+	head->disk->fops = &nvme_ns_head_ops;
+	head->disk->private_data = head;
+	head->disk->queue = q;
+	head->disk->flags = GENHD_FL_EXT_DEVT;
+	sprintf(head->disk->disk_name, "nvme%dn%d",
+			ctrl->subsys->instance, head->instance);
+	return 0;
+
+out_cleanup_queue:
+	blk_cleanup_queue(q);
+out:
+	return -ENOMEM;
+}
+
+static void nvme_mpath_set_live(struct nvme_ns *ns)
+{
+	struct nvme_ns_head *head = ns->head;
+
+	lockdep_assert_held(&ns->head->lock);
+
+	if (!head->disk)
+		return;
+
+	if (!(head->disk->flags & GENHD_FL_UP))
+		device_add_disk(&head->subsys->dev, head->disk,
+				nvme_ns_id_attr_groups);
+
+	synchronize_srcu(&ns->head->srcu);
+	kblockd_schedule_work(&ns->head->requeue_work);
+}
+
+static int nvme_parse_ana_log(struct nvme_ctrl *ctrl, void *data,
+		int (*cb)(struct nvme_ctrl *ctrl, struct nvme_ana_group_desc *,
+			void *))
+{
+	void *base = ctrl->ana_log_buf;
+	size_t offset = sizeof(struct nvme_ana_rsp_hdr);
+	int error, i;
+
+	lockdep_assert_held(&ctrl->ana_lock);
+
+	for (i = 0; i < le16_to_cpu(ctrl->ana_log_buf->ngrps); i++) {
+		struct nvme_ana_group_desc *desc = base + offset;
+		u32 nr_nsids = le32_to_cpu(desc->nnsids);
+		size_t nsid_buf_size = nr_nsids * sizeof(__le32);
+
+		if (WARN_ON_ONCE(desc->grpid == 0))
+			return -EINVAL;
+		if (WARN_ON_ONCE(le32_to_cpu(desc->grpid) > ctrl->anagrpmax))
+			return -EINVAL;
+		if (WARN_ON_ONCE(desc->state == 0))
+			return -EINVAL;
+		if (WARN_ON_ONCE(desc->state > NVME_ANA_CHANGE))
+			return -EINVAL;
+
+		offset += sizeof(*desc);
+		if (WARN_ON_ONCE(offset > ctrl->ana_log_size - nsid_buf_size))
+			return -EINVAL;
+
+		error = cb(ctrl, desc, data);
+		if (error)
+			return error;
+
+		offset += nsid_buf_size;
+		if (WARN_ON_ONCE(offset > ctrl->ana_log_size - sizeof(*desc)))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static inline bool nvme_state_is_live(enum nvme_ana_state state)
+{
+	return state == NVME_ANA_OPTIMIZED || state == NVME_ANA_NONOPTIMIZED;
+}
+
+static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc,
+		struct nvme_ns *ns)
+{
+	mutex_lock(&ns->head->lock);
+	ns->ana_grpid = le32_to_cpu(desc->grpid);
+	ns->ana_state = desc->state;
+	clear_bit(NVME_NS_ANA_PENDING, &ns->flags);
+
+	if (nvme_state_is_live(ns->ana_state))
+		nvme_mpath_set_live(ns);
+	mutex_unlock(&ns->head->lock);
+}
+
+static int nvme_update_ana_state(struct nvme_ctrl *ctrl,
+		struct nvme_ana_group_desc *desc, void *data)
+{
+	u32 nr_nsids = le32_to_cpu(desc->nnsids), n = 0;
+	unsigned *nr_change_groups = data;
+	struct nvme_ns *ns;
+
+	dev_info(ctrl->device, "ANA group %d: %s.\n",
+			le32_to_cpu(desc->grpid),
+			nvme_ana_state_names[desc->state]);
+
+	if (desc->state == NVME_ANA_CHANGE)
+		(*nr_change_groups)++;
+
+	if (!nr_nsids)
+		return 0;
+
+	down_read(&ctrl->namespaces_rwsem);
+	list_for_each_entry(ns, &ctrl->namespaces, list) {
+		unsigned nsid;
+again:
+		nsid = le32_to_cpu(desc->nsids[n]);
+		if (ns->head->ns_id < nsid)
+			continue;
+		if (ns->head->ns_id == nsid)
+			nvme_update_ns_ana_state(desc, ns);
+		if (++n == nr_nsids)
+			break;
+		if (ns->head->ns_id > nsid)
+			goto again;
+	}
+	up_read(&ctrl->namespaces_rwsem);
+	return 0;
+}
+
+static int nvme_read_ana_log(struct nvme_ctrl *ctrl, bool groups_only)
+{
+	u32 nr_change_groups = 0;
+	int error;
+
+	mutex_lock(&ctrl->ana_lock);
+	error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_ANA,
+			groups_only ? NVME_ANA_LOG_RGO : 0,
+			ctrl->ana_log_buf, ctrl->ana_log_size, 0);
+	if (error) {
+		dev_warn(ctrl->device, "Failed to get ANA log: %d\n", error);
+		goto out_unlock;
+	}
+
+	error = nvme_parse_ana_log(ctrl, &nr_change_groups,
+			nvme_update_ana_state);
+	if (error)
+		goto out_unlock;
+
+	/*
+	 * In theory we should have an ANATT timer per group as they might enter
+	 * the change state at different times.  But that is a lot of overhead
+	 * just to protect against a target that keeps entering new changes
+	 * states while never finishing previous ones.  But we'll still
+	 * eventually time out once all groups are in change state, so this
+	 * isn't a big deal.
+	 *
+	 * We also double the ANATT value to provide some slack for transports
+	 * or AEN processing overhead.
+	 */
+	if (nr_change_groups)
+		mod_timer(&ctrl->anatt_timer, ctrl->anatt * HZ * 2 + jiffies);
+	else
+		del_timer_sync(&ctrl->anatt_timer);
+out_unlock:
+	mutex_unlock(&ctrl->ana_lock);
+	return error;
+}
+
+static void nvme_ana_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ana_work);
+
+	nvme_read_ana_log(ctrl, false);
+}
+
+static void nvme_anatt_timeout(struct timer_list *t)
+{
+	struct nvme_ctrl *ctrl = from_timer(ctrl, t, anatt_timer);
+
+	dev_info(ctrl->device, "ANATT timeout, resetting controller.\n");
+	nvme_reset_ctrl(ctrl);
+}
+
+void nvme_mpath_stop(struct nvme_ctrl *ctrl)
+{
+	if (!nvme_ctrl_use_ana(ctrl))
+		return;
+	del_timer_sync(&ctrl->anatt_timer);
+	cancel_work_sync(&ctrl->ana_work);
+}
+
+static ssize_t ana_grpid_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	return sprintf(buf, "%d\n", nvme_get_ns_from_dev(dev)->ana_grpid);
+}
+DEVICE_ATTR_RO(ana_grpid);
+
+static ssize_t ana_state_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
+
+	return sprintf(buf, "%s\n", nvme_ana_state_names[ns->ana_state]);
+}
+DEVICE_ATTR_RO(ana_state);
+
+static int nvme_lookup_ana_group_desc(struct nvme_ctrl *ctrl,
+		struct nvme_ana_group_desc *desc, void *data)
+{
+	struct nvme_ana_group_desc *dst = data;
+
+	if (desc->grpid != dst->grpid)
+		return 0;
+
+	*dst = *desc;
+	return -ENXIO; /* just break out of the loop */
+}
+
+void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id)
+{
+	if (nvme_ctrl_use_ana(ns->ctrl)) {
+		struct nvme_ana_group_desc desc = {
+			.grpid = id->anagrpid,
+			.state = 0,
+		};
+
+		mutex_lock(&ns->ctrl->ana_lock);
+		ns->ana_grpid = le32_to_cpu(id->anagrpid);
+		nvme_parse_ana_log(ns->ctrl, &desc, nvme_lookup_ana_group_desc);
+		mutex_unlock(&ns->ctrl->ana_lock);
+		if (desc.state) {
+			/* found the group desc: update */
+			nvme_update_ns_ana_state(&desc, ns);
+		} else {
+			/* group desc not found: trigger a re-read */
+			set_bit(NVME_NS_ANA_PENDING, &ns->flags);
+			queue_work(nvme_wq, &ns->ctrl->ana_work);
+		}
+	} else {
+		mutex_lock(&ns->head->lock);
+		ns->ana_state = NVME_ANA_OPTIMIZED; 
+		nvme_mpath_set_live(ns);
+		mutex_unlock(&ns->head->lock);
+	}
+
+	if (bdi_cap_stable_pages_required(ns->queue->backing_dev_info)) {
+		struct gendisk *disk = ns->head->disk;
+
+		if (disk)
+			disk->queue->backing_dev_info->capabilities |=
+					BDI_CAP_STABLE_WRITES;
+	}
+}
+
+void nvme_mpath_remove_disk(struct nvme_ns_head *head)
+{
+	if (!head->disk)
+		return;
+	if (head->disk->flags & GENHD_FL_UP)
+		del_gendisk(head->disk);
+	blk_set_queue_dying(head->disk->queue);
+	/* make sure all pending bios are cleaned up */
+	kblockd_schedule_work(&head->requeue_work);
+	flush_work(&head->requeue_work);
+	blk_cleanup_queue(head->disk->queue);
+	put_disk(head->disk);
+}
+
+int nvme_mpath_init(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
+{
+	int error;
+
+	/* check if multipath is enabled and we have the capability */
+	if (!multipath || !ctrl->subsys || !(ctrl->subsys->cmic & (1 << 3)))
+		return 0;
+
+	ctrl->anacap = id->anacap;
+	ctrl->anatt = id->anatt;
+	ctrl->nanagrpid = le32_to_cpu(id->nanagrpid);
+	ctrl->anagrpmax = le32_to_cpu(id->anagrpmax);
+
+	mutex_init(&ctrl->ana_lock);
+	timer_setup(&ctrl->anatt_timer, nvme_anatt_timeout, 0);
+	ctrl->ana_log_size = sizeof(struct nvme_ana_rsp_hdr) +
+		ctrl->nanagrpid * sizeof(struct nvme_ana_group_desc);
+	ctrl->ana_log_size += ctrl->max_namespaces * sizeof(__le32);
+
+	if (ctrl->ana_log_size > ctrl->max_hw_sectors << SECTOR_SHIFT) {
+		dev_err(ctrl->device,
+			"ANA log page size (%zd) larger than MDTS (%d).\n",
+			ctrl->ana_log_size,
+			ctrl->max_hw_sectors << SECTOR_SHIFT);
+		dev_err(ctrl->device, "disabling ANA support.\n");
+		return 0;
+	}
+
+	INIT_WORK(&ctrl->ana_work, nvme_ana_work);
+	kfree(ctrl->ana_log_buf);
+	ctrl->ana_log_buf = kmalloc(ctrl->ana_log_size, GFP_KERNEL);
+	if (!ctrl->ana_log_buf) {
+		error = -ENOMEM;
+		goto out;
+	}
+
+	error = nvme_read_ana_log(ctrl, false);
+	if (error)
+		goto out_free_ana_log_buf;
+	return 0;
+out_free_ana_log_buf:
+	kfree(ctrl->ana_log_buf);
+	ctrl->ana_log_buf = NULL;
+out:
+	return error;
+}
+
+void nvme_mpath_uninit(struct nvme_ctrl *ctrl)
+{
+	kfree(ctrl->ana_log_buf);
+	ctrl->ana_log_buf = NULL;
+}
+
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
new file mode 100644
index 000000000..276975506
--- /dev/null
+++ b/drivers/nvme/host/nvme.h
@@ -0,0 +1,618 @@
+/*
+ * Copyright (c) 2011-2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef _NVME_H
+#define _NVME_H
+
+#include <linux/nvme.h>
+#include <linux/cdev.h>
+#include <linux/pci.h>
+#include <linux/kref.h>
+#include <linux/blk-mq.h>
+#include <linux/lightnvm.h>
+#include <linux/sed-opal.h>
+#include <linux/fault-inject.h>
+#include <linux/rcupdate.h>
+
+extern unsigned int nvme_io_timeout;
+#define NVME_IO_TIMEOUT	(nvme_io_timeout * HZ)
+
+extern unsigned int admin_timeout;
+#define ADMIN_TIMEOUT	(admin_timeout * HZ)
+
+#define NVME_DEFAULT_KATO	5
+#define NVME_KATO_GRACE		10
+
+extern struct workqueue_struct *nvme_wq;
+extern struct workqueue_struct *nvme_reset_wq;
+extern struct workqueue_struct *nvme_delete_wq;
+
+enum {
+	NVME_NS_LBA		= 0,
+	NVME_NS_LIGHTNVM	= 1,
+};
+
+/*
+ * List of workarounds for devices that required behavior not specified in
+ * the standard.
+ */
+enum nvme_quirks {
+	/*
+	 * Prefers I/O aligned to a stripe size specified in a vendor
+	 * specific Identify field.
+	 */
+	NVME_QUIRK_STRIPE_SIZE			= (1 << 0),
+
+	/*
+	 * The controller doesn't handle Identify value others than 0 or 1
+	 * correctly.
+	 */
+	NVME_QUIRK_IDENTIFY_CNS			= (1 << 1),
+
+	/*
+	 * The controller deterministically returns O's on reads to
+	 * logical blocks that deallocate was called on.
+	 */
+	NVME_QUIRK_DEALLOCATE_ZEROES		= (1 << 2),
+
+	/*
+	 * The controller needs a delay before starts checking the device
+	 * readiness, which is done by reading the NVME_CSTS_RDY bit.
+	 */
+	NVME_QUIRK_DELAY_BEFORE_CHK_RDY		= (1 << 3),
+
+	/*
+	 * APST should not be used.
+	 */
+	NVME_QUIRK_NO_APST			= (1 << 4),
+
+	/*
+	 * The deepest sleep state should not be used.
+	 */
+	NVME_QUIRK_NO_DEEPEST_PS		= (1 << 5),
+
+	/*
+	 * Supports the LighNVM command set if indicated in vs[1].
+	 */
+	NVME_QUIRK_LIGHTNVM			= (1 << 6),
+
+	/*
+	 * Set MEDIUM priority on SQ creation
+	 */
+	NVME_QUIRK_MEDIUM_PRIO_SQ		= (1 << 7),
+};
+
+/*
+ * Common request structure for NVMe passthrough.  All drivers must have
+ * this structure as the first member of their request-private data.
+ */
+struct nvme_request {
+	struct nvme_command	*cmd;
+	union nvme_result	result;
+	u8			retries;
+	u8			flags;
+	u16			status;
+	struct nvme_ctrl	*ctrl;
+};
+
+/*
+ * Mark a bio as coming in through the mpath node.
+ */
+#define REQ_NVME_MPATH		REQ_DRV
+
+enum {
+	NVME_REQ_CANCELLED		= (1 << 0),
+	NVME_REQ_USERCMD		= (1 << 1),
+};
+
+static inline struct nvme_request *nvme_req(struct request *req)
+{
+	return blk_mq_rq_to_pdu(req);
+}
+
+static inline u16 nvme_req_qid(struct request *req)
+{
+	if (!req->rq_disk)
+		return 0;
+	return blk_mq_unique_tag_to_hwq(blk_mq_unique_tag(req)) + 1;
+}
+
+/* The below value is the specific amount of delay needed before checking
+ * readiness in case of the PCI_DEVICE(0x1c58, 0x0003), which needs the
+ * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
+ * found empirically.
+ */
+#define NVME_QUIRK_DELAY_AMOUNT		2300
+
+enum nvme_ctrl_state {
+	NVME_CTRL_NEW,
+	NVME_CTRL_LIVE,
+	NVME_CTRL_ADMIN_ONLY,    /* Only admin queue live */
+	NVME_CTRL_RESETTING,
+	NVME_CTRL_CONNECTING,
+	NVME_CTRL_DELETING,
+	NVME_CTRL_DEAD,
+};
+
+struct nvme_ctrl {
+	enum nvme_ctrl_state state;
+	bool identified;
+	spinlock_t lock;
+	struct mutex scan_lock;
+	const struct nvme_ctrl_ops *ops;
+	struct request_queue *admin_q;
+	struct request_queue *connect_q;
+	struct device *dev;
+	int instance;
+	struct blk_mq_tag_set *tagset;
+	struct blk_mq_tag_set *admin_tagset;
+	struct list_head namespaces;
+	struct rw_semaphore namespaces_rwsem;
+	struct device ctrl_device;
+	struct device *device;	/* char device */
+	struct cdev cdev;
+	struct work_struct reset_work;
+	struct work_struct delete_work;
+
+	struct nvme_subsystem *subsys;
+	struct list_head subsys_entry;
+
+	struct opal_dev *opal_dev;
+
+	char name[12];
+	u16 cntlid;
+
+	u32 ctrl_config;
+	u16 mtfa;
+	u32 queue_count;
+
+	u64 cap;
+	u32 page_size;
+	u32 max_hw_sectors;
+	u32 max_segments;
+	u16 oncs;
+	u16 oacs;
+	u16 nssa;
+	u16 nr_streams;
+	u32 max_namespaces;
+	atomic_t abort_limit;
+	u8 vwc;
+	u32 vs;
+	u32 sgls;
+	u16 kas;
+	u8 npss;
+	u8 apsta;
+	u32 oaes;
+	u32 aen_result;
+	unsigned int shutdown_timeout;
+	unsigned int kato;
+	bool subsystem;
+	unsigned long quirks;
+	struct nvme_id_power_state psd[32];
+	struct nvme_effects_log *effects;
+	struct work_struct scan_work;
+	struct work_struct async_event_work;
+	struct delayed_work ka_work;
+	struct nvme_command ka_cmd;
+	struct work_struct fw_act_work;
+	unsigned long events;
+	bool created;
+
+#ifdef CONFIG_NVME_MULTIPATH
+	/* asymmetric namespace access: */
+	u8 anacap;
+	u8 anatt;
+	u32 anagrpmax;
+	u32 nanagrpid;
+	struct mutex ana_lock;
+	struct nvme_ana_rsp_hdr *ana_log_buf;
+	size_t ana_log_size;
+	struct timer_list anatt_timer;
+	struct work_struct ana_work;
+#endif
+
+	/* Power saving configuration */
+	u64 ps_max_latency_us;
+	bool apst_enabled;
+
+	/* PCIe only: */
+	u32 hmpre;
+	u32 hmmin;
+	u32 hmminds;
+	u16 hmmaxd;
+
+	/* Fabrics only */
+	u16 sqsize;
+	u32 ioccsz;
+	u32 iorcsz;
+	u16 icdoff;
+	u16 maxcmd;
+	int nr_reconnects;
+	struct nvmf_ctrl_options *opts;
+
+	struct page *discard_page;
+	unsigned long discard_page_busy;
+};
+
+struct nvme_subsystem {
+	int			instance;
+	struct device		dev;
+	/*
+	 * Because we unregister the device on the last put we need
+	 * a separate refcount.
+	 */
+	struct kref		ref;
+	struct list_head	entry;
+	struct mutex		lock;
+	struct list_head	ctrls;
+	struct list_head	nsheads;
+	char			subnqn[NVMF_NQN_SIZE];
+	char			serial[20];
+	char			model[40];
+	char			firmware_rev[8];
+	u8			cmic;
+	u16			vendor_id;
+	struct ida		ns_ida;
+};
+
+/*
+ * Container structure for uniqueue namespace identifiers.
+ */
+struct nvme_ns_ids {
+	u8	eui64[8];
+	u8	nguid[16];
+	uuid_t	uuid;
+};
+
+/*
+ * Anchor structure for namespaces.  There is one for each namespace in a
+ * NVMe subsystem that any of our controllers can see, and the namespace
+ * structure for each controller is chained of it.  For private namespaces
+ * there is a 1:1 relation to our namespace structures, that is ->list
+ * only ever has a single entry for private namespaces.
+ */
+struct nvme_ns_head {
+#ifdef CONFIG_NVME_MULTIPATH
+	struct gendisk		*disk;
+	struct nvme_ns __rcu	*current_path;
+	struct bio_list		requeue_list;
+	spinlock_t		requeue_lock;
+	struct work_struct	requeue_work;
+	struct mutex		lock;
+#endif
+	struct list_head	list;
+	struct srcu_struct      srcu;
+	struct nvme_subsystem	*subsys;
+	unsigned		ns_id;
+	struct nvme_ns_ids	ids;
+	struct list_head	entry;
+	struct kref		ref;
+	int			instance;
+};
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+struct nvme_fault_inject {
+	struct fault_attr attr;
+	struct dentry *parent;
+	bool dont_retry;	/* DNR, do not retry */
+	u16 status;		/* status code */
+};
+#endif
+
+struct nvme_ns {
+	struct list_head list;
+
+	struct nvme_ctrl *ctrl;
+	struct request_queue *queue;
+	struct gendisk *disk;
+#ifdef CONFIG_NVME_MULTIPATH
+	enum nvme_ana_state ana_state;
+	u32 ana_grpid;
+#endif
+	struct list_head siblings;
+	struct nvm_dev *ndev;
+	struct kref kref;
+	struct nvme_ns_head *head;
+
+	int lba_shift;
+	u16 ms;
+	u16 sgs;
+	u32 sws;
+	bool ext;
+	u8 pi_type;
+	unsigned long flags;
+#define NVME_NS_REMOVING	0
+#define NVME_NS_DEAD     	1
+#define NVME_NS_ANA_PENDING	2
+	u16 noiob;
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+	struct nvme_fault_inject fault_inject;
+#endif
+
+};
+
+struct nvme_ctrl_ops {
+	const char *name;
+	struct module *module;
+	unsigned int flags;
+#define NVME_F_FABRICS			(1 << 0)
+#define NVME_F_METADATA_SUPPORTED	(1 << 1)
+	int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
+	int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
+	int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
+	void (*free_ctrl)(struct nvme_ctrl *ctrl);
+	void (*submit_async_event)(struct nvme_ctrl *ctrl);
+	void (*delete_ctrl)(struct nvme_ctrl *ctrl);
+	int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
+	void (*stop_ctrl)(struct nvme_ctrl *ctrl);
+};
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+void nvme_fault_inject_init(struct nvme_ns *ns);
+void nvme_fault_inject_fini(struct nvme_ns *ns);
+void nvme_should_fail(struct request *req);
+#else
+static inline void nvme_fault_inject_init(struct nvme_ns *ns) {}
+static inline void nvme_fault_inject_fini(struct nvme_ns *ns) {}
+static inline void nvme_should_fail(struct request *req) {}
+#endif
+
+static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
+{
+	u32 val = 0;
+
+	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
+		return false;
+	return val & NVME_CSTS_RDY;
+}
+
+static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
+{
+	if (!ctrl->subsystem)
+		return -ENOTTY;
+	return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
+}
+
+static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
+{
+	return (sector >> (ns->lba_shift - 9));
+}
+
+static inline void nvme_end_request(struct request *req, __le16 status,
+		union nvme_result result)
+{
+	struct nvme_request *rq = nvme_req(req);
+
+	rq->status = le16_to_cpu(status) >> 1;
+	rq->result = result;
+	/* inject error when permitted by fault injection framework */
+	nvme_should_fail(req);
+	blk_mq_complete_request(req);
+}
+
+static inline void nvme_get_ctrl(struct nvme_ctrl *ctrl)
+{
+	get_device(ctrl->device);
+}
+
+static inline void nvme_put_ctrl(struct nvme_ctrl *ctrl)
+{
+	put_device(ctrl->device);
+}
+
+void nvme_complete_rq(struct request *req);
+void nvme_cancel_request(struct request *req, void *data, bool reserved);
+bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
+		enum nvme_ctrl_state new_state);
+int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
+int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
+int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
+int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
+		const struct nvme_ctrl_ops *ops, unsigned long quirks);
+void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
+void nvme_start_ctrl(struct nvme_ctrl *ctrl);
+void nvme_stop_ctrl(struct nvme_ctrl *ctrl);
+void nvme_put_ctrl(struct nvme_ctrl *ctrl);
+int nvme_init_identify(struct nvme_ctrl *ctrl);
+
+void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
+
+int nvme_sec_submit(void *data, u16 spsp, u8 secp, void *buffer, size_t len,
+		bool send);
+
+void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
+		volatile union nvme_result *res);
+
+void nvme_stop_queues(struct nvme_ctrl *ctrl);
+void nvme_start_queues(struct nvme_ctrl *ctrl);
+void nvme_kill_queues(struct nvme_ctrl *ctrl);
+void nvme_unfreeze(struct nvme_ctrl *ctrl);
+void nvme_wait_freeze(struct nvme_ctrl *ctrl);
+void nvme_wait_freeze_timeout(struct nvme_ctrl *ctrl, long timeout);
+void nvme_start_freeze(struct nvme_ctrl *ctrl);
+
+#define NVME_QID_ANY -1
+struct request *nvme_alloc_request(struct request_queue *q,
+		struct nvme_command *cmd, blk_mq_req_flags_t flags, int qid);
+void nvme_cleanup_cmd(struct request *req);
+blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
+		struct nvme_command *cmd);
+int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
+		void *buf, unsigned bufflen);
+int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
+		union nvme_result *result, void *buffer, unsigned bufflen,
+		unsigned timeout, int qid, int at_head,
+		blk_mq_req_flags_t flags);
+int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
+void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
+int nvme_reset_ctrl(struct nvme_ctrl *ctrl);
+int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl);
+int nvme_delete_ctrl(struct nvme_ctrl *ctrl);
+int nvme_delete_ctrl_sync(struct nvme_ctrl *ctrl);
+
+int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp,
+		void *log, size_t size, u64 offset);
+
+extern const struct attribute_group *nvme_ns_id_attr_groups[];
+extern const struct block_device_operations nvme_ns_head_ops;
+
+#ifdef CONFIG_NVME_MULTIPATH
+static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl)
+{
+	return ctrl->ana_log_buf != NULL;
+}
+
+void nvme_mpath_unfreeze(struct nvme_subsystem *subsys);
+void nvme_mpath_wait_freeze(struct nvme_subsystem *subsys);
+void nvme_mpath_start_freeze(struct nvme_subsystem *subsys);
+void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+			struct nvme_ctrl *ctrl, int *flags);
+bool nvme_failover_req(struct request *req);
+void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl);
+int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl,struct nvme_ns_head *head);
+void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id);
+void nvme_mpath_remove_disk(struct nvme_ns_head *head);
+int nvme_mpath_init(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id);
+void nvme_mpath_uninit(struct nvme_ctrl *ctrl);
+void nvme_mpath_stop(struct nvme_ctrl *ctrl);
+
+static inline void nvme_mpath_clear_current_path(struct nvme_ns *ns)
+{
+	struct nvme_ns_head *head = ns->head;
+
+	if (head && ns == rcu_access_pointer(head->current_path))
+		rcu_assign_pointer(head->current_path, NULL);
+}
+struct nvme_ns *nvme_find_path(struct nvme_ns_head *head);
+
+static inline void nvme_mpath_check_last_path(struct nvme_ns *ns)
+{
+	struct nvme_ns_head *head = ns->head;
+
+	if (head->disk && list_empty(&head->list))
+		kblockd_schedule_work(&head->requeue_work);
+}
+
+static inline void nvme_mpath_update_disk_size(struct gendisk *disk)
+{
+	struct block_device *bdev = bdget_disk(disk, 0);
+
+	if (bdev) {
+		bd_set_size(bdev, get_capacity(disk) << SECTOR_SHIFT);
+		bdput(bdev);
+	}
+}
+
+extern struct device_attribute dev_attr_ana_grpid;
+extern struct device_attribute dev_attr_ana_state;
+
+#else
+static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl)
+{
+	return false;
+}
+/*
+ * Without the multipath code enabled, multiple controller per subsystems are
+ * visible as devices and thus we cannot use the subsystem instance.
+ */
+static inline void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+				      struct nvme_ctrl *ctrl, int *flags)
+{
+	sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
+}
+
+static inline bool nvme_failover_req(struct request *req)
+{
+	return false;
+}
+static inline void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl)
+{
+}
+static inline int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl,
+		struct nvme_ns_head *head)
+{
+	return 0;
+}
+static inline void nvme_mpath_add_disk(struct nvme_ns *ns,
+		struct nvme_id_ns *id)
+{
+}
+static inline void nvme_mpath_remove_disk(struct nvme_ns_head *head)
+{
+}
+static inline void nvme_mpath_clear_current_path(struct nvme_ns *ns)
+{
+}
+static inline void nvme_mpath_check_last_path(struct nvme_ns *ns)
+{
+}
+static inline int nvme_mpath_init(struct nvme_ctrl *ctrl,
+		struct nvme_id_ctrl *id)
+{
+	if (ctrl->subsys->cmic & (1 << 3))
+		dev_warn(ctrl->device,
+"Please enable CONFIG_NVME_MULTIPATH for full support of multi-port devices.\n");
+	return 0;
+}
+static inline void nvme_mpath_uninit(struct nvme_ctrl *ctrl)
+{
+}
+static inline void nvme_mpath_stop(struct nvme_ctrl *ctrl)
+{
+}
+static inline void nvme_mpath_unfreeze(struct nvme_subsystem *subsys)
+{
+}
+static inline void nvme_mpath_wait_freeze(struct nvme_subsystem *subsys)
+{
+}
+static inline void nvme_mpath_start_freeze(struct nvme_subsystem *subsys)
+{
+}
+static inline void nvme_mpath_update_disk_size(struct gendisk *disk)
+{
+}
+#endif /* CONFIG_NVME_MULTIPATH */
+
+#ifdef CONFIG_NVM
+void nvme_nvm_update_nvm_info(struct nvme_ns *ns);
+int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node);
+void nvme_nvm_unregister(struct nvme_ns *ns);
+extern const struct attribute_group nvme_nvm_attr_group;
+int nvme_nvm_ioctl(struct nvme_ns *ns, unsigned int cmd, unsigned long arg);
+#else
+static inline void nvme_nvm_update_nvm_info(struct nvme_ns *ns) {};
+static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
+				    int node)
+{
+	return 0;
+}
+
+static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
+static inline int nvme_nvm_ioctl(struct nvme_ns *ns, unsigned int cmd,
+							unsigned long arg)
+{
+	return -ENOTTY;
+}
+#endif /* CONFIG_NVM */
+
+static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
+{
+	return dev_to_disk(dev)->private_data;
+}
+
+int __init nvme_core_init(void);
+void nvme_core_exit(void);
+
+#endif /* _NVME_H */
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
new file mode 100644
index 000000000..b06d2b6bd
--- /dev/null
+++ b/drivers/nvme/host/pci.c
@@ -0,0 +1,2775 @@
+/*
+ * NVM Express device driver
+ * Copyright (c) 2011-2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/aer.h>
+#include <linux/async.h>
+#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
+#include <linux/blk-mq-pci.h>
+#include <linux/dmi.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/once.h>
+#include <linux/pci.h>
+#include <linux/t10-pi.h>
+#include <linux/types.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/sed-opal.h>
+
+#include "nvme.h"
+
+#define SQ_SIZE(depth)		(depth * sizeof(struct nvme_command))
+#define CQ_SIZE(depth)		(depth * sizeof(struct nvme_completion))
+
+#define SGES_PER_PAGE	(PAGE_SIZE / sizeof(struct nvme_sgl_desc))
+
+/*
+ * These can be higher, but we need to ensure that any command doesn't
+ * require an sg allocation that needs more than a page of data.
+ */
+#define NVME_MAX_KB_SZ	4096
+#define NVME_MAX_SEGS	127
+
+static int use_threaded_interrupts;
+module_param(use_threaded_interrupts, int, 0);
+
+static bool use_cmb_sqes = true;
+module_param(use_cmb_sqes, bool, 0444);
+MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
+
+static unsigned int max_host_mem_size_mb = 128;
+module_param(max_host_mem_size_mb, uint, 0444);
+MODULE_PARM_DESC(max_host_mem_size_mb,
+	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
+
+static unsigned int sgl_threshold = SZ_32K;
+module_param(sgl_threshold, uint, 0644);
+MODULE_PARM_DESC(sgl_threshold,
+		"Use SGLs when average request segment size is larger or equal to "
+		"this size. Use 0 to disable SGLs.");
+
+static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
+static const struct kernel_param_ops io_queue_depth_ops = {
+	.set = io_queue_depth_set,
+	.get = param_get_int,
+};
+
+static int io_queue_depth = 1024;
+module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
+MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
+
+struct nvme_dev;
+struct nvme_queue;
+
+static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
+
+/*
+ * Represents an NVM Express device.  Each nvme_dev is a PCI function.
+ */
+struct nvme_dev {
+	struct nvme_queue *queues;
+	struct blk_mq_tag_set tagset;
+	struct blk_mq_tag_set admin_tagset;
+	u32 __iomem *dbs;
+	struct device *dev;
+	struct dma_pool *prp_page_pool;
+	struct dma_pool *prp_small_pool;
+	unsigned online_queues;
+	unsigned max_qid;
+	unsigned int num_vecs;
+	int q_depth;
+	u32 db_stride;
+	void __iomem *bar;
+	unsigned long bar_mapped_size;
+	struct work_struct remove_work;
+	struct mutex shutdown_lock;
+	bool subsystem;
+	void __iomem *cmb;
+	pci_bus_addr_t cmb_bus_addr;
+	u64 cmb_size;
+	u32 cmbsz;
+	u32 cmbloc;
+	struct nvme_ctrl ctrl;
+	struct completion ioq_wait;
+
+	mempool_t *iod_mempool;
+
+	/* shadow doorbell buffer support: */
+	u32 *dbbuf_dbs;
+	dma_addr_t dbbuf_dbs_dma_addr;
+	u32 *dbbuf_eis;
+	dma_addr_t dbbuf_eis_dma_addr;
+
+	/* host memory buffer support: */
+	u64 host_mem_size;
+	u32 nr_host_mem_descs;
+	dma_addr_t host_mem_descs_dma;
+	struct nvme_host_mem_buf_desc *host_mem_descs;
+	void **host_mem_desc_bufs;
+};
+
+static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
+{
+	int n = 0, ret;
+
+	ret = kstrtoint(val, 10, &n);
+	if (ret != 0 || n < 2)
+		return -EINVAL;
+
+	return param_set_int(val, kp);
+}
+
+static inline unsigned int sq_idx(unsigned int qid, u32 stride)
+{
+	return qid * 2 * stride;
+}
+
+static inline unsigned int cq_idx(unsigned int qid, u32 stride)
+{
+	return (qid * 2 + 1) * stride;
+}
+
+static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
+{
+	return container_of(ctrl, struct nvme_dev, ctrl);
+}
+
+/*
+ * An NVM Express queue.  Each device has at least two (one for admin
+ * commands and one for I/O commands).
+ */
+struct nvme_queue {
+	struct device *q_dmadev;
+	struct nvme_dev *dev;
+	spinlock_t sq_lock;
+	struct nvme_command *sq_cmds;
+	struct nvme_command __iomem *sq_cmds_io;
+	spinlock_t cq_lock ____cacheline_aligned_in_smp;
+	volatile struct nvme_completion *cqes;
+	struct blk_mq_tags **tags;
+	dma_addr_t sq_dma_addr;
+	dma_addr_t cq_dma_addr;
+	u32 __iomem *q_db;
+	u16 q_depth;
+	s16 cq_vector;
+	u16 sq_tail;
+	u16 cq_head;
+	u16 last_cq_head;
+	u16 qid;
+	u8 cq_phase;
+	u32 *dbbuf_sq_db;
+	u32 *dbbuf_cq_db;
+	u32 *dbbuf_sq_ei;
+	u32 *dbbuf_cq_ei;
+};
+
+/*
+ * The nvme_iod describes the data in an I/O, including the list of PRP
+ * entries.  You can't see it in this data structure because C doesn't let
+ * me express that.  Use nvme_init_iod to ensure there's enough space
+ * allocated to store the PRP list.
+ */
+struct nvme_iod {
+	struct nvme_request req;
+	struct nvme_queue *nvmeq;
+	bool use_sgl;
+	int aborted;
+	int npages;		/* In the PRP list. 0 means small pool in use */
+	int nents;		/* Used in scatterlist */
+	int length;		/* Of data, in bytes */
+	dma_addr_t first_dma;
+	struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
+	struct scatterlist *sg;
+	struct scatterlist inline_sg[0];
+};
+
+/*
+ * Check we didin't inadvertently grow the command struct
+ */
+static inline void _nvme_check_size(void)
+{
+	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
+	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
+	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
+	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
+}
+
+static inline unsigned int nvme_dbbuf_size(u32 stride)
+{
+	return ((num_possible_cpus() + 1) * 8 * stride);
+}
+
+static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
+{
+	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
+
+	if (dev->dbbuf_dbs)
+		return 0;
+
+	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
+					    &dev->dbbuf_dbs_dma_addr,
+					    GFP_KERNEL);
+	if (!dev->dbbuf_dbs)
+		return -ENOMEM;
+	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
+					    &dev->dbbuf_eis_dma_addr,
+					    GFP_KERNEL);
+	if (!dev->dbbuf_eis) {
+		dma_free_coherent(dev->dev, mem_size,
+				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
+		dev->dbbuf_dbs = NULL;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
+{
+	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
+
+	if (dev->dbbuf_dbs) {
+		dma_free_coherent(dev->dev, mem_size,
+				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
+		dev->dbbuf_dbs = NULL;
+	}
+	if (dev->dbbuf_eis) {
+		dma_free_coherent(dev->dev, mem_size,
+				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
+		dev->dbbuf_eis = NULL;
+	}
+}
+
+static void nvme_dbbuf_init(struct nvme_dev *dev,
+			    struct nvme_queue *nvmeq, int qid)
+{
+	if (!dev->dbbuf_dbs || !qid)
+		return;
+
+	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
+	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
+	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
+	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
+}
+
+static void nvme_dbbuf_free(struct nvme_queue *nvmeq)
+{
+	if (!nvmeq->qid)
+		return;
+
+	nvmeq->dbbuf_sq_db = NULL;
+	nvmeq->dbbuf_cq_db = NULL;
+	nvmeq->dbbuf_sq_ei = NULL;
+	nvmeq->dbbuf_cq_ei = NULL;
+}
+
+static void nvme_dbbuf_set(struct nvme_dev *dev)
+{
+	struct nvme_command c;
+	unsigned int i;
+
+	if (!dev->dbbuf_dbs)
+		return;
+
+	memset(&c, 0, sizeof(c));
+	c.dbbuf.opcode = nvme_admin_dbbuf;
+	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
+	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
+
+	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
+		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
+		/* Free memory and continue on */
+		nvme_dbbuf_dma_free(dev);
+
+		for (i = 1; i <= dev->online_queues; i++)
+			nvme_dbbuf_free(&dev->queues[i]);
+	}
+}
+
+static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
+{
+	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
+}
+
+/* Update dbbuf and return true if an MMIO is required */
+static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
+					      volatile u32 *dbbuf_ei)
+{
+	if (dbbuf_db) {
+		u16 old_value;
+
+		/*
+		 * Ensure that the queue is written before updating
+		 * the doorbell in memory
+		 */
+		wmb();
+
+		old_value = *dbbuf_db;
+		*dbbuf_db = value;
+
+		/*
+		 * Ensure that the doorbell is updated before reading the event
+		 * index from memory.  The controller needs to provide similar
+		 * ordering to ensure the envent index is updated before reading
+		 * the doorbell.
+		 */
+		mb();
+
+		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
+			return false;
+	}
+
+	return true;
+}
+
+/*
+ * Max size of iod being embedded in the request payload
+ */
+#define NVME_INT_PAGES		2
+#define NVME_INT_BYTES(dev)	(NVME_INT_PAGES * (dev)->ctrl.page_size)
+
+/*
+ * Will slightly overestimate the number of pages needed.  This is OK
+ * as it only leads to a small amount of wasted memory for the lifetime of
+ * the I/O.
+ */
+static int nvme_npages(unsigned size, struct nvme_dev *dev)
+{
+	unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size,
+				      dev->ctrl.page_size);
+	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
+}
+
+/*
+ * Calculates the number of pages needed for the SGL segments. For example a 4k
+ * page can accommodate 256 SGL descriptors.
+ */
+static int nvme_pci_npages_sgl(unsigned int num_seg)
+{
+	return DIV_ROUND_UP(num_seg * sizeof(struct nvme_sgl_desc), PAGE_SIZE);
+}
+
+static unsigned int nvme_pci_iod_alloc_size(struct nvme_dev *dev,
+		unsigned int size, unsigned int nseg, bool use_sgl)
+{
+	size_t alloc_size;
+
+	if (use_sgl)
+		alloc_size = sizeof(__le64 *) * nvme_pci_npages_sgl(nseg);
+	else
+		alloc_size = sizeof(__le64 *) * nvme_npages(size, dev);
+
+	return alloc_size + sizeof(struct scatterlist) * nseg;
+}
+
+static unsigned int nvme_pci_cmd_size(struct nvme_dev *dev, bool use_sgl)
+{
+	unsigned int alloc_size = nvme_pci_iod_alloc_size(dev,
+				    NVME_INT_BYTES(dev), NVME_INT_PAGES,
+				    use_sgl);
+
+	return sizeof(struct nvme_iod) + alloc_size;
+}
+
+static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+				unsigned int hctx_idx)
+{
+	struct nvme_dev *dev = data;
+	struct nvme_queue *nvmeq = &dev->queues[0];
+
+	WARN_ON(hctx_idx != 0);
+	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
+	WARN_ON(nvmeq->tags);
+
+	hctx->driver_data = nvmeq;
+	nvmeq->tags = &dev->admin_tagset.tags[0];
+	return 0;
+}
+
+static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
+{
+	struct nvme_queue *nvmeq = hctx->driver_data;
+
+	nvmeq->tags = NULL;
+}
+
+static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+			  unsigned int hctx_idx)
+{
+	struct nvme_dev *dev = data;
+	struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1];
+
+	if (!nvmeq->tags)
+		nvmeq->tags = &dev->tagset.tags[hctx_idx];
+
+	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
+	hctx->driver_data = nvmeq;
+	return 0;
+}
+
+static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
+		unsigned int hctx_idx, unsigned int numa_node)
+{
+	struct nvme_dev *dev = set->driver_data;
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
+	struct nvme_queue *nvmeq = &dev->queues[queue_idx];
+
+	BUG_ON(!nvmeq);
+	iod->nvmeq = nvmeq;
+
+	nvme_req(req)->ctrl = &dev->ctrl;
+	return 0;
+}
+
+static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
+{
+	struct nvme_dev *dev = set->driver_data;
+
+	return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev),
+			dev->num_vecs > 1 ? 1 /* admin queue */ : 0);
+}
+
+/**
+ * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
+ * @nvmeq: The queue to use
+ * @cmd: The command to send
+ */
+static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
+{
+	spin_lock(&nvmeq->sq_lock);
+	if (nvmeq->sq_cmds_io)
+		memcpy_toio(&nvmeq->sq_cmds_io[nvmeq->sq_tail], cmd,
+				sizeof(*cmd));
+	else
+		memcpy(&nvmeq->sq_cmds[nvmeq->sq_tail], cmd, sizeof(*cmd));
+
+	if (++nvmeq->sq_tail == nvmeq->q_depth)
+		nvmeq->sq_tail = 0;
+	if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
+			nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
+		writel(nvmeq->sq_tail, nvmeq->q_db);
+	spin_unlock(&nvmeq->sq_lock);
+}
+
+static void **nvme_pci_iod_list(struct request *req)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	return (void **)(iod->sg + blk_rq_nr_phys_segments(req));
+}
+
+static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	int nseg = blk_rq_nr_phys_segments(req);
+	unsigned int avg_seg_size;
+
+	if (nseg == 0)
+		return false;
+
+	avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
+
+	if (!(dev->ctrl.sgls & ((1 << 0) | (1 << 1))))
+		return false;
+	if (!iod->nvmeq->qid)
+		return false;
+	if (!sgl_threshold || avg_seg_size < sgl_threshold)
+		return false;
+	return true;
+}
+
+static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
+	int nseg = blk_rq_nr_phys_segments(rq);
+	unsigned int size = blk_rq_payload_bytes(rq);
+
+	iod->use_sgl = nvme_pci_use_sgls(dev, rq);
+
+	if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
+		iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC);
+		if (!iod->sg)
+			return BLK_STS_RESOURCE;
+	} else {
+		iod->sg = iod->inline_sg;
+	}
+
+	iod->aborted = 0;
+	iod->npages = -1;
+	iod->nents = 0;
+	iod->length = size;
+
+	return BLK_STS_OK;
+}
+
+static void nvme_free_iod(struct nvme_dev *dev, struct request *req)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	const int last_prp = dev->ctrl.page_size / sizeof(__le64) - 1;
+	dma_addr_t dma_addr = iod->first_dma, next_dma_addr;
+
+	int i;
+
+	if (iod->npages == 0)
+		dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
+			dma_addr);
+
+	for (i = 0; i < iod->npages; i++) {
+		void *addr = nvme_pci_iod_list(req)[i];
+
+		if (iod->use_sgl) {
+			struct nvme_sgl_desc *sg_list = addr;
+
+			next_dma_addr =
+			    le64_to_cpu((sg_list[SGES_PER_PAGE - 1]).addr);
+		} else {
+			__le64 *prp_list = addr;
+
+			next_dma_addr = le64_to_cpu(prp_list[last_prp]);
+		}
+
+		dma_pool_free(dev->prp_page_pool, addr, dma_addr);
+		dma_addr = next_dma_addr;
+	}
+
+	if (iod->sg != iod->inline_sg)
+		mempool_free(iod->sg, dev->iod_mempool);
+}
+
+static void nvme_print_sgl(struct scatterlist *sgl, int nents)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sgl, sg, nents, i) {
+		dma_addr_t phys = sg_phys(sg);
+		pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
+			"dma_address:%pad dma_length:%d\n",
+			i, &phys, sg->offset, sg->length, &sg_dma_address(sg),
+			sg_dma_len(sg));
+	}
+}
+
+static blk_status_t nvme_pci_setup_prps(struct nvme_dev *dev,
+		struct request *req, struct nvme_rw_command *cmnd)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	struct dma_pool *pool;
+	int length = blk_rq_payload_bytes(req);
+	struct scatterlist *sg = iod->sg;
+	int dma_len = sg_dma_len(sg);
+	u64 dma_addr = sg_dma_address(sg);
+	u32 page_size = dev->ctrl.page_size;
+	int offset = dma_addr & (page_size - 1);
+	__le64 *prp_list;
+	void **list = nvme_pci_iod_list(req);
+	dma_addr_t prp_dma;
+	int nprps, i;
+
+	length -= (page_size - offset);
+	if (length <= 0) {
+		iod->first_dma = 0;
+		goto done;
+	}
+
+	dma_len -= (page_size - offset);
+	if (dma_len) {
+		dma_addr += (page_size - offset);
+	} else {
+		sg = sg_next(sg);
+		dma_addr = sg_dma_address(sg);
+		dma_len = sg_dma_len(sg);
+	}
+
+	if (length <= page_size) {
+		iod->first_dma = dma_addr;
+		goto done;
+	}
+
+	nprps = DIV_ROUND_UP(length, page_size);
+	if (nprps <= (256 / 8)) {
+		pool = dev->prp_small_pool;
+		iod->npages = 0;
+	} else {
+		pool = dev->prp_page_pool;
+		iod->npages = 1;
+	}
+
+	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
+	if (!prp_list) {
+		iod->first_dma = dma_addr;
+		iod->npages = -1;
+		return BLK_STS_RESOURCE;
+	}
+	list[0] = prp_list;
+	iod->first_dma = prp_dma;
+	i = 0;
+	for (;;) {
+		if (i == page_size >> 3) {
+			__le64 *old_prp_list = prp_list;
+			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
+			if (!prp_list)
+				return BLK_STS_RESOURCE;
+			list[iod->npages++] = prp_list;
+			prp_list[0] = old_prp_list[i - 1];
+			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
+			i = 1;
+		}
+		prp_list[i++] = cpu_to_le64(dma_addr);
+		dma_len -= page_size;
+		dma_addr += page_size;
+		length -= page_size;
+		if (length <= 0)
+			break;
+		if (dma_len > 0)
+			continue;
+		if (unlikely(dma_len < 0))
+			goto bad_sgl;
+		sg = sg_next(sg);
+		dma_addr = sg_dma_address(sg);
+		dma_len = sg_dma_len(sg);
+	}
+
+done:
+	cmnd->dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
+	cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma);
+
+	return BLK_STS_OK;
+
+ bad_sgl:
+	WARN(DO_ONCE(nvme_print_sgl, iod->sg, iod->nents),
+			"Invalid SGL for payload:%d nents:%d\n",
+			blk_rq_payload_bytes(req), iod->nents);
+	return BLK_STS_IOERR;
+}
+
+static void nvme_pci_sgl_set_data(struct nvme_sgl_desc *sge,
+		struct scatterlist *sg)
+{
+	sge->addr = cpu_to_le64(sg_dma_address(sg));
+	sge->length = cpu_to_le32(sg_dma_len(sg));
+	sge->type = NVME_SGL_FMT_DATA_DESC << 4;
+}
+
+static void nvme_pci_sgl_set_seg(struct nvme_sgl_desc *sge,
+		dma_addr_t dma_addr, int entries)
+{
+	sge->addr = cpu_to_le64(dma_addr);
+	if (entries < SGES_PER_PAGE) {
+		sge->length = cpu_to_le32(entries * sizeof(*sge));
+		sge->type = NVME_SGL_FMT_LAST_SEG_DESC << 4;
+	} else {
+		sge->length = cpu_to_le32(PAGE_SIZE);
+		sge->type = NVME_SGL_FMT_SEG_DESC << 4;
+	}
+}
+
+static blk_status_t nvme_pci_setup_sgls(struct nvme_dev *dev,
+		struct request *req, struct nvme_rw_command *cmd, int entries)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	struct dma_pool *pool;
+	struct nvme_sgl_desc *sg_list;
+	struct scatterlist *sg = iod->sg;
+	dma_addr_t sgl_dma;
+	int i = 0;
+
+	/* setting the transfer type as SGL */
+	cmd->flags = NVME_CMD_SGL_METABUF;
+
+	if (entries == 1) {
+		nvme_pci_sgl_set_data(&cmd->dptr.sgl, sg);
+		return BLK_STS_OK;
+	}
+
+	if (entries <= (256 / sizeof(struct nvme_sgl_desc))) {
+		pool = dev->prp_small_pool;
+		iod->npages = 0;
+	} else {
+		pool = dev->prp_page_pool;
+		iod->npages = 1;
+	}
+
+	sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
+	if (!sg_list) {
+		iod->npages = -1;
+		return BLK_STS_RESOURCE;
+	}
+
+	nvme_pci_iod_list(req)[0] = sg_list;
+	iod->first_dma = sgl_dma;
+
+	nvme_pci_sgl_set_seg(&cmd->dptr.sgl, sgl_dma, entries);
+
+	do {
+		if (i == SGES_PER_PAGE) {
+			struct nvme_sgl_desc *old_sg_desc = sg_list;
+			struct nvme_sgl_desc *link = &old_sg_desc[i - 1];
+
+			sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
+			if (!sg_list)
+				return BLK_STS_RESOURCE;
+
+			i = 0;
+			nvme_pci_iod_list(req)[iod->npages++] = sg_list;
+			sg_list[i++] = *link;
+			nvme_pci_sgl_set_seg(link, sgl_dma, entries);
+		}
+
+		nvme_pci_sgl_set_data(&sg_list[i++], sg);
+		sg = sg_next(sg);
+	} while (--entries > 0);
+
+	return BLK_STS_OK;
+}
+
+static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
+		struct nvme_command *cmnd)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	struct request_queue *q = req->q;
+	enum dma_data_direction dma_dir = rq_data_dir(req) ?
+			DMA_TO_DEVICE : DMA_FROM_DEVICE;
+	blk_status_t ret = BLK_STS_IOERR;
+	int nr_mapped;
+
+	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
+	iod->nents = blk_rq_map_sg(q, req, iod->sg);
+	if (!iod->nents)
+		goto out;
+
+	ret = BLK_STS_RESOURCE;
+	nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
+			DMA_ATTR_NO_WARN);
+	if (!nr_mapped)
+		goto out;
+
+	if (iod->use_sgl)
+		ret = nvme_pci_setup_sgls(dev, req, &cmnd->rw, nr_mapped);
+	else
+		ret = nvme_pci_setup_prps(dev, req, &cmnd->rw);
+
+	if (ret != BLK_STS_OK)
+		goto out_unmap;
+
+	ret = BLK_STS_IOERR;
+	if (blk_integrity_rq(req)) {
+		if (blk_rq_count_integrity_sg(q, req->bio) != 1)
+			goto out_unmap;
+
+		sg_init_table(&iod->meta_sg, 1);
+		if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
+			goto out_unmap;
+
+		if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
+			goto out_unmap;
+	}
+
+	if (blk_integrity_rq(req))
+		cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
+	return BLK_STS_OK;
+
+out_unmap:
+	dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
+out:
+	return ret;
+}
+
+static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	enum dma_data_direction dma_dir = rq_data_dir(req) ?
+			DMA_TO_DEVICE : DMA_FROM_DEVICE;
+
+	if (iod->nents) {
+		dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
+		if (blk_integrity_rq(req))
+			dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
+	}
+
+	nvme_cleanup_cmd(req);
+	nvme_free_iod(dev, req);
+}
+
+/*
+ * NOTE: ns is NULL when called on the admin queue.
+ */
+static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
+			 const struct blk_mq_queue_data *bd)
+{
+	struct nvme_ns *ns = hctx->queue->queuedata;
+	struct nvme_queue *nvmeq = hctx->driver_data;
+	struct nvme_dev *dev = nvmeq->dev;
+	struct request *req = bd->rq;
+	struct nvme_command cmnd;
+	blk_status_t ret;
+
+	/*
+	 * We should not need to do this, but we're still using this to
+	 * ensure we can drain requests on a dying queue.
+	 */
+	if (unlikely(nvmeq->cq_vector < 0))
+		return BLK_STS_IOERR;
+
+	ret = nvme_setup_cmd(ns, req, &cmnd);
+	if (ret)
+		return ret;
+
+	ret = nvme_init_iod(req, dev);
+	if (ret)
+		goto out_free_cmd;
+
+	if (blk_rq_nr_phys_segments(req)) {
+		ret = nvme_map_data(dev, req, &cmnd);
+		if (ret)
+			goto out_cleanup_iod;
+	}
+
+	blk_mq_start_request(req);
+	nvme_submit_cmd(nvmeq, &cmnd);
+	return BLK_STS_OK;
+out_cleanup_iod:
+	nvme_free_iod(dev, req);
+out_free_cmd:
+	nvme_cleanup_cmd(req);
+	return ret;
+}
+
+static void nvme_pci_complete_rq(struct request *req)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+
+	nvme_unmap_data(iod->nvmeq->dev, req);
+	nvme_complete_rq(req);
+}
+
+/* We read the CQE phase first to check if the rest of the entry is valid */
+static inline bool nvme_cqe_pending(struct nvme_queue *nvmeq)
+{
+	return (le16_to_cpu(nvmeq->cqes[nvmeq->cq_head].status) & 1) ==
+			nvmeq->cq_phase;
+}
+
+static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
+{
+	u16 head = nvmeq->cq_head;
+
+	if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
+					      nvmeq->dbbuf_cq_ei))
+		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
+}
+
+static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
+{
+	volatile struct nvme_completion *cqe = &nvmeq->cqes[idx];
+	struct request *req;
+
+	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
+		dev_warn(nvmeq->dev->ctrl.device,
+			"invalid id %d completed on queue %d\n",
+			cqe->command_id, le16_to_cpu(cqe->sq_id));
+		return;
+	}
+
+	/*
+	 * AEN requests are special as they don't time out and can
+	 * survive any kind of queue freeze and often don't respond to
+	 * aborts.  We don't even bother to allocate a struct request
+	 * for them but rather special case them here.
+	 */
+	if (unlikely(nvmeq->qid == 0 &&
+			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH)) {
+		nvme_complete_async_event(&nvmeq->dev->ctrl,
+				cqe->status, &cqe->result);
+		return;
+	}
+
+	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
+	nvme_end_request(req, cqe->status, cqe->result);
+}
+
+static void nvme_complete_cqes(struct nvme_queue *nvmeq, u16 start, u16 end)
+{
+	while (start != end) {
+		nvme_handle_cqe(nvmeq, start);
+		if (++start == nvmeq->q_depth)
+			start = 0;
+	}
+}
+
+static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
+{
+	if (nvmeq->cq_head == nvmeq->q_depth - 1) {
+		nvmeq->cq_head = 0;
+		nvmeq->cq_phase = !nvmeq->cq_phase;
+	} else {
+		nvmeq->cq_head++;
+	}
+}
+
+static inline bool nvme_process_cq(struct nvme_queue *nvmeq, u16 *start,
+		u16 *end, int tag)
+{
+	bool found = false;
+
+	*start = nvmeq->cq_head;
+	while (!found && nvme_cqe_pending(nvmeq)) {
+		if (nvmeq->cqes[nvmeq->cq_head].command_id == tag)
+			found = true;
+		nvme_update_cq_head(nvmeq);
+	}
+	*end = nvmeq->cq_head;
+
+	if (*start != *end)
+		nvme_ring_cq_doorbell(nvmeq);
+	return found;
+}
+
+static irqreturn_t nvme_irq(int irq, void *data)
+{
+	struct nvme_queue *nvmeq = data;
+	irqreturn_t ret = IRQ_NONE;
+	u16 start, end;
+
+	spin_lock(&nvmeq->cq_lock);
+	if (nvmeq->cq_head != nvmeq->last_cq_head)
+		ret = IRQ_HANDLED;
+	nvme_process_cq(nvmeq, &start, &end, -1);
+	nvmeq->last_cq_head = nvmeq->cq_head;
+	spin_unlock(&nvmeq->cq_lock);
+
+	if (start != end) {
+		nvme_complete_cqes(nvmeq, start, end);
+		return IRQ_HANDLED;
+	}
+
+	return ret;
+}
+
+static irqreturn_t nvme_irq_check(int irq, void *data)
+{
+	struct nvme_queue *nvmeq = data;
+	if (nvme_cqe_pending(nvmeq))
+		return IRQ_WAKE_THREAD;
+	return IRQ_NONE;
+}
+
+static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
+{
+	u16 start, end;
+	bool found;
+
+	if (!nvme_cqe_pending(nvmeq))
+		return 0;
+
+	spin_lock_irq(&nvmeq->cq_lock);
+	found = nvme_process_cq(nvmeq, &start, &end, tag);
+	spin_unlock_irq(&nvmeq->cq_lock);
+
+	nvme_complete_cqes(nvmeq, start, end);
+	return found;
+}
+
+static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
+{
+	struct nvme_queue *nvmeq = hctx->driver_data;
+
+	return __nvme_poll(nvmeq, tag);
+}
+
+static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
+{
+	struct nvme_dev *dev = to_nvme_dev(ctrl);
+	struct nvme_queue *nvmeq = &dev->queues[0];
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	c.common.opcode = nvme_admin_async_event;
+	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
+	nvme_submit_cmd(nvmeq, &c);
+}
+
+static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	c.delete_queue.opcode = opcode;
+	c.delete_queue.qid = cpu_to_le16(id);
+
+	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
+}
+
+static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
+		struct nvme_queue *nvmeq, s16 vector)
+{
+	struct nvme_command c;
+	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
+
+	/*
+	 * Note: we (ab)use the fact that the prp fields survive if no data
+	 * is attached to the request.
+	 */
+	memset(&c, 0, sizeof(c));
+	c.create_cq.opcode = nvme_admin_create_cq;
+	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
+	c.create_cq.cqid = cpu_to_le16(qid);
+	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
+	c.create_cq.cq_flags = cpu_to_le16(flags);
+	c.create_cq.irq_vector = cpu_to_le16(vector);
+
+	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
+}
+
+static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
+						struct nvme_queue *nvmeq)
+{
+	struct nvme_ctrl *ctrl = &dev->ctrl;
+	struct nvme_command c;
+	int flags = NVME_QUEUE_PHYS_CONTIG;
+
+	/*
+	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
+	 * set. Since URGENT priority is zeroes, it makes all queues
+	 * URGENT.
+	 */
+	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
+		flags |= NVME_SQ_PRIO_MEDIUM;
+
+	/*
+	 * Note: we (ab)use the fact that the prp fields survive if no data
+	 * is attached to the request.
+	 */
+	memset(&c, 0, sizeof(c));
+	c.create_sq.opcode = nvme_admin_create_sq;
+	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
+	c.create_sq.sqid = cpu_to_le16(qid);
+	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
+	c.create_sq.sq_flags = cpu_to_le16(flags);
+	c.create_sq.cqid = cpu_to_le16(qid);
+
+	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
+}
+
+static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
+{
+	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
+}
+
+static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
+{
+	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
+}
+
+static void abort_endio(struct request *req, blk_status_t error)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	struct nvme_queue *nvmeq = iod->nvmeq;
+
+	dev_warn(nvmeq->dev->ctrl.device,
+		 "Abort status: 0x%x", nvme_req(req)->status);
+	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
+	blk_mq_free_request(req);
+}
+
+static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
+{
+
+	/* If true, indicates loss of adapter communication, possibly by a
+	 * NVMe Subsystem reset.
+	 */
+	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
+
+	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
+	switch (dev->ctrl.state) {
+	case NVME_CTRL_RESETTING:
+	case NVME_CTRL_CONNECTING:
+		return false;
+	default:
+		break;
+	}
+
+	/* We shouldn't reset unless the controller is on fatal error state
+	 * _or_ if we lost the communication with it.
+	 */
+	if (!(csts & NVME_CSTS_CFS) && !nssro)
+		return false;
+
+	return true;
+}
+
+static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
+{
+	/* Read a config register to help see what died. */
+	u16 pci_status;
+	int result;
+
+	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
+				      &pci_status);
+	if (result == PCIBIOS_SUCCESSFUL)
+		dev_warn(dev->ctrl.device,
+			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
+			 csts, pci_status);
+	else
+		dev_warn(dev->ctrl.device,
+			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
+			 csts, result);
+}
+
+static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
+{
+	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+	struct nvme_queue *nvmeq = iod->nvmeq;
+	struct nvme_dev *dev = nvmeq->dev;
+	struct request *abort_req;
+	struct nvme_command cmd;
+	bool shutdown = false;
+	u32 csts = readl(dev->bar + NVME_REG_CSTS);
+
+	/* If PCI error recovery process is happening, we cannot reset or
+	 * the recovery mechanism will surely fail.
+	 */
+	mb();
+	if (pci_channel_offline(to_pci_dev(dev->dev)))
+		return BLK_EH_RESET_TIMER;
+
+	/*
+	 * Reset immediately if the controller is failed
+	 */
+	if (nvme_should_reset(dev, csts)) {
+		nvme_warn_reset(dev, csts);
+		nvme_dev_disable(dev, false);
+		nvme_reset_ctrl(&dev->ctrl);
+		return BLK_EH_DONE;
+	}
+
+	/*
+	 * Did we miss an interrupt?
+	 */
+	if (__nvme_poll(nvmeq, req->tag)) {
+		dev_warn(dev->ctrl.device,
+			 "I/O %d QID %d timeout, completion polled\n",
+			 req->tag, nvmeq->qid);
+		return BLK_EH_DONE;
+	}
+
+	/*
+	 * Shutdown immediately if controller times out while starting. The
+	 * reset work will see the pci device disabled when it gets the forced
+	 * cancellation error. All outstanding requests are completed on
+	 * shutdown, so we return BLK_EH_DONE.
+	 */
+	switch (dev->ctrl.state) {
+	case NVME_CTRL_DELETING:
+		shutdown = true;
+	case NVME_CTRL_CONNECTING:
+	case NVME_CTRL_RESETTING:
+		dev_warn_ratelimited(dev->ctrl.device,
+			 "I/O %d QID %d timeout, disable controller\n",
+			 req->tag, nvmeq->qid);
+		nvme_dev_disable(dev, shutdown);
+		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
+		return BLK_EH_DONE;
+	default:
+		break;
+	}
+
+	/*
+ 	 * Shutdown the controller immediately and schedule a reset if the
+ 	 * command was already aborted once before and still hasn't been
+ 	 * returned to the driver, or if this is the admin queue.
+	 */
+	if (!nvmeq->qid || iod->aborted) {
+		dev_warn(dev->ctrl.device,
+			 "I/O %d QID %d timeout, reset controller\n",
+			 req->tag, nvmeq->qid);
+		nvme_dev_disable(dev, false);
+		nvme_reset_ctrl(&dev->ctrl);
+
+		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
+		return BLK_EH_DONE;
+	}
+
+	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
+		atomic_inc(&dev->ctrl.abort_limit);
+		return BLK_EH_RESET_TIMER;
+	}
+	iod->aborted = 1;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.abort.opcode = nvme_admin_abort_cmd;
+	cmd.abort.cid = req->tag;
+	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
+
+	dev_warn(nvmeq->dev->ctrl.device,
+		"I/O %d QID %d timeout, aborting\n",
+		 req->tag, nvmeq->qid);
+
+	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
+			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
+	if (IS_ERR(abort_req)) {
+		atomic_inc(&dev->ctrl.abort_limit);
+		return BLK_EH_RESET_TIMER;
+	}
+
+	abort_req->timeout = ADMIN_TIMEOUT;
+	abort_req->end_io_data = NULL;
+	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
+
+	/*
+	 * The aborted req will be completed on receiving the abort req.
+	 * We enable the timer again. If hit twice, it'll cause a device reset,
+	 * as the device then is in a faulty state.
+	 */
+	return BLK_EH_RESET_TIMER;
+}
+
+static void nvme_free_queue(struct nvme_queue *nvmeq)
+{
+	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
+				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
+	if (nvmeq->sq_cmds)
+		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
+					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
+}
+
+static void nvme_free_queues(struct nvme_dev *dev, int lowest)
+{
+	int i;
+
+	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
+		dev->ctrl.queue_count--;
+		nvme_free_queue(&dev->queues[i]);
+	}
+}
+
+/**
+ * nvme_suspend_queue - put queue into suspended state
+ * @nvmeq - queue to suspend
+ */
+static int nvme_suspend_queue(struct nvme_queue *nvmeq)
+{
+	int vector;
+
+	spin_lock_irq(&nvmeq->cq_lock);
+	if (nvmeq->cq_vector == -1) {
+		spin_unlock_irq(&nvmeq->cq_lock);
+		return 1;
+	}
+	vector = nvmeq->cq_vector;
+	nvmeq->dev->online_queues--;
+	nvmeq->cq_vector = -1;
+	spin_unlock_irq(&nvmeq->cq_lock);
+
+	/*
+	 * Ensure that nvme_queue_rq() sees it ->cq_vector == -1 without
+	 * having to grab the lock.
+	 */
+	mb();
+
+	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
+		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
+
+	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
+
+	return 0;
+}
+
+static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
+{
+	struct nvme_queue *nvmeq = &dev->queues[0];
+	u16 start, end;
+
+	if (shutdown)
+		nvme_shutdown_ctrl(&dev->ctrl);
+	else
+		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
+
+	spin_lock_irq(&nvmeq->cq_lock);
+	nvme_process_cq(nvmeq, &start, &end, -1);
+	spin_unlock_irq(&nvmeq->cq_lock);
+
+	nvme_complete_cqes(nvmeq, start, end);
+}
+
+static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
+				int entry_size)
+{
+	int q_depth = dev->q_depth;
+	unsigned q_size_aligned = roundup(q_depth * entry_size,
+					  dev->ctrl.page_size);
+
+	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
+		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
+		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
+		q_depth = div_u64(mem_per_q, entry_size);
+
+		/*
+		 * Ensure the reduced q_depth is above some threshold where it
+		 * would be better to map queues in system memory with the
+		 * original depth
+		 */
+		if (q_depth < 64)
+			return -ENOMEM;
+	}
+
+	return q_depth;
+}
+
+static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
+				int qid, int depth)
+{
+	/* CMB SQEs will be mapped before creation */
+	if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS))
+		return 0;
+
+	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
+					    &nvmeq->sq_dma_addr, GFP_KERNEL);
+	if (!nvmeq->sq_cmds)
+		return -ENOMEM;
+	return 0;
+}
+
+static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
+{
+	struct nvme_queue *nvmeq = &dev->queues[qid];
+
+	if (dev->ctrl.queue_count > qid)
+		return 0;
+
+	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
+					  &nvmeq->cq_dma_addr, GFP_KERNEL);
+	if (!nvmeq->cqes)
+		goto free_nvmeq;
+
+	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
+		goto free_cqdma;
+
+	nvmeq->q_dmadev = dev->dev;
+	nvmeq->dev = dev;
+	spin_lock_init(&nvmeq->sq_lock);
+	spin_lock_init(&nvmeq->cq_lock);
+	nvmeq->cq_head = 0;
+	nvmeq->cq_phase = 1;
+	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
+	nvmeq->q_depth = depth;
+	nvmeq->qid = qid;
+	nvmeq->cq_vector = -1;
+	dev->ctrl.queue_count++;
+
+	return 0;
+
+ free_cqdma:
+	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
+							nvmeq->cq_dma_addr);
+ free_nvmeq:
+	return -ENOMEM;
+}
+
+static int queue_request_irq(struct nvme_queue *nvmeq)
+{
+	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
+	int nr = nvmeq->dev->ctrl.instance;
+
+	if (use_threaded_interrupts) {
+		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
+				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
+	} else {
+		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
+				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
+	}
+}
+
+static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
+{
+	struct nvme_dev *dev = nvmeq->dev;
+
+	spin_lock_irq(&nvmeq->cq_lock);
+	nvmeq->sq_tail = 0;
+	nvmeq->cq_head = 0;
+	nvmeq->cq_phase = 1;
+	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
+	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
+	nvme_dbbuf_init(dev, nvmeq, qid);
+	dev->online_queues++;
+	spin_unlock_irq(&nvmeq->cq_lock);
+}
+
+static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
+{
+	struct nvme_dev *dev = nvmeq->dev;
+	int result;
+	s16 vector;
+
+	if (dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
+		unsigned offset = (qid - 1) * roundup(SQ_SIZE(nvmeq->q_depth),
+						      dev->ctrl.page_size);
+		nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset;
+		nvmeq->sq_cmds_io = dev->cmb + offset;
+	}
+
+	/*
+	 * A queue's vector matches the queue identifier unless the controller
+	 * has only one vector available.
+	 */
+	vector = dev->num_vecs == 1 ? 0 : qid;
+	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
+	if (result)
+		return result;
+
+	result = adapter_alloc_sq(dev, qid, nvmeq);
+	if (result < 0)
+		return result;
+	else if (result)
+		goto release_cq;
+
+	/*
+	 * Set cq_vector after alloc cq/sq, otherwise nvme_suspend_queue will
+	 * invoke free_irq for it and cause a 'Trying to free already-free IRQ
+	 * xxx' warning if the create CQ/SQ command times out.
+	 */
+	nvmeq->cq_vector = vector;
+	nvme_init_queue(nvmeq, qid);
+	result = queue_request_irq(nvmeq);
+	if (result < 0)
+		goto release_sq;
+
+	return result;
+
+release_sq:
+	nvmeq->cq_vector = -1;
+	dev->online_queues--;
+	adapter_delete_sq(dev, qid);
+release_cq:
+	adapter_delete_cq(dev, qid);
+	return result;
+}
+
+static const struct blk_mq_ops nvme_mq_admin_ops = {
+	.queue_rq	= nvme_queue_rq,
+	.complete	= nvme_pci_complete_rq,
+	.init_hctx	= nvme_admin_init_hctx,
+	.exit_hctx      = nvme_admin_exit_hctx,
+	.init_request	= nvme_init_request,
+	.timeout	= nvme_timeout,
+};
+
+static const struct blk_mq_ops nvme_mq_ops = {
+	.queue_rq	= nvme_queue_rq,
+	.complete	= nvme_pci_complete_rq,
+	.init_hctx	= nvme_init_hctx,
+	.init_request	= nvme_init_request,
+	.map_queues	= nvme_pci_map_queues,
+	.timeout	= nvme_timeout,
+	.poll		= nvme_poll,
+};
+
+static void nvme_dev_remove_admin(struct nvme_dev *dev)
+{
+	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
+		/*
+		 * If the controller was reset during removal, it's possible
+		 * user requests may be waiting on a stopped queue. Start the
+		 * queue to flush these to completion.
+		 */
+		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
+		blk_cleanup_queue(dev->ctrl.admin_q);
+		blk_mq_free_tag_set(&dev->admin_tagset);
+	}
+}
+
+static int nvme_alloc_admin_tags(struct nvme_dev *dev)
+{
+	if (!dev->ctrl.admin_q) {
+		dev->admin_tagset.ops = &nvme_mq_admin_ops;
+		dev->admin_tagset.nr_hw_queues = 1;
+
+		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
+		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
+		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
+		dev->admin_tagset.cmd_size = nvme_pci_cmd_size(dev, false);
+		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
+		dev->admin_tagset.driver_data = dev;
+
+		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
+			return -ENOMEM;
+		dev->ctrl.admin_tagset = &dev->admin_tagset;
+
+		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
+		if (IS_ERR(dev->ctrl.admin_q)) {
+			blk_mq_free_tag_set(&dev->admin_tagset);
+			dev->ctrl.admin_q = NULL;
+			return -ENOMEM;
+		}
+		if (!blk_get_queue(dev->ctrl.admin_q)) {
+			nvme_dev_remove_admin(dev);
+			dev->ctrl.admin_q = NULL;
+			return -ENODEV;
+		}
+	} else
+		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
+
+	return 0;
+}
+
+static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
+{
+	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
+}
+
+static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	if (size <= dev->bar_mapped_size)
+		return 0;
+	if (size > pci_resource_len(pdev, 0))
+		return -ENOMEM;
+	if (dev->bar)
+		iounmap(dev->bar);
+	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
+	if (!dev->bar) {
+		dev->bar_mapped_size = 0;
+		return -ENOMEM;
+	}
+	dev->bar_mapped_size = size;
+	dev->dbs = dev->bar + NVME_REG_DBS;
+
+	return 0;
+}
+
+static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
+{
+	int result;
+	u32 aqa;
+	struct nvme_queue *nvmeq;
+
+	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
+	if (result < 0)
+		return result;
+
+	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
+				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
+
+	if (dev->subsystem &&
+	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
+		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
+
+	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
+	if (result < 0)
+		return result;
+
+	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
+	if (result)
+		return result;
+
+	nvmeq = &dev->queues[0];
+	aqa = nvmeq->q_depth - 1;
+	aqa |= aqa << 16;
+
+	writel(aqa, dev->bar + NVME_REG_AQA);
+	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
+	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
+
+	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
+	if (result)
+		return result;
+
+	nvmeq->cq_vector = 0;
+	nvme_init_queue(nvmeq, 0);
+	result = queue_request_irq(nvmeq);
+	if (result) {
+		nvmeq->cq_vector = -1;
+		return result;
+	}
+
+	return result;
+}
+
+static int nvme_create_io_queues(struct nvme_dev *dev)
+{
+	unsigned i, max;
+	int ret = 0;
+
+	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
+		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
+			ret = -ENOMEM;
+			break;
+		}
+	}
+
+	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
+	for (i = dev->online_queues; i <= max; i++) {
+		ret = nvme_create_queue(&dev->queues[i], i);
+		if (ret)
+			break;
+	}
+
+	/*
+	 * Ignore failing Create SQ/CQ commands, we can continue with less
+	 * than the desired amount of queues, and even a controller without
+	 * I/O queues can still be used to issue admin commands.  This might
+	 * be useful to upgrade a buggy firmware for example.
+	 */
+	return ret >= 0 ? 0 : ret;
+}
+
+static ssize_t nvme_cmb_show(struct device *dev,
+			     struct device_attribute *attr,
+			     char *buf)
+{
+	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
+
+	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
+		       ndev->cmbloc, ndev->cmbsz);
+}
+static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
+
+static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
+{
+	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
+
+	return 1ULL << (12 + 4 * szu);
+}
+
+static u32 nvme_cmb_size(struct nvme_dev *dev)
+{
+	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
+}
+
+static void nvme_map_cmb(struct nvme_dev *dev)
+{
+	u64 size, offset;
+	resource_size_t bar_size;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	int bar;
+
+	if (dev->cmb_size)
+		return;
+
+	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
+	if (!dev->cmbsz)
+		return;
+	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
+
+	if (!use_cmb_sqes)
+		return;
+
+	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
+	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
+	bar = NVME_CMB_BIR(dev->cmbloc);
+	bar_size = pci_resource_len(pdev, bar);
+
+	if (offset > bar_size)
+		return;
+
+	/*
+	 * Controllers may support a CMB size larger than their BAR,
+	 * for example, due to being behind a bridge. Reduce the CMB to
+	 * the reported size of the BAR
+	 */
+	if (size > bar_size - offset)
+		size = bar_size - offset;
+
+	dev->cmb = ioremap_wc(pci_resource_start(pdev, bar) + offset, size);
+	if (!dev->cmb)
+		return;
+	dev->cmb_bus_addr = pci_bus_address(pdev, bar) + offset;
+	dev->cmb_size = size;
+
+	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
+				    &dev_attr_cmb.attr, NULL))
+		dev_warn(dev->ctrl.device,
+			 "failed to add sysfs attribute for CMB\n");
+}
+
+static inline void nvme_release_cmb(struct nvme_dev *dev)
+{
+	if (dev->cmb) {
+		iounmap(dev->cmb);
+		dev->cmb = NULL;
+		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
+					     &dev_attr_cmb.attr, NULL);
+		dev->cmbsz = 0;
+	}
+}
+
+static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
+{
+	u64 dma_addr = dev->host_mem_descs_dma;
+	struct nvme_command c;
+	int ret;
+
+	memset(&c, 0, sizeof(c));
+	c.features.opcode	= nvme_admin_set_features;
+	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
+	c.features.dword11	= cpu_to_le32(bits);
+	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
+					      ilog2(dev->ctrl.page_size));
+	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
+	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
+	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
+
+	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
+	if (ret) {
+		dev_warn(dev->ctrl.device,
+			 "failed to set host mem (err %d, flags %#x).\n",
+			 ret, bits);
+	}
+	return ret;
+}
+
+static void nvme_free_host_mem(struct nvme_dev *dev)
+{
+	int i;
+
+	for (i = 0; i < dev->nr_host_mem_descs; i++) {
+		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
+		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
+
+		dma_free_attrs(dev->dev, size, dev->host_mem_desc_bufs[i],
+			       le64_to_cpu(desc->addr),
+			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
+	}
+
+	kfree(dev->host_mem_desc_bufs);
+	dev->host_mem_desc_bufs = NULL;
+	dma_free_coherent(dev->dev,
+			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
+			dev->host_mem_descs, dev->host_mem_descs_dma);
+	dev->host_mem_descs = NULL;
+	dev->nr_host_mem_descs = 0;
+}
+
+static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
+		u32 chunk_size)
+{
+	struct nvme_host_mem_buf_desc *descs;
+	u32 max_entries, len;
+	dma_addr_t descs_dma;
+	int i = 0;
+	void **bufs;
+	u64 size, tmp;
+
+	tmp = (preferred + chunk_size - 1);
+	do_div(tmp, chunk_size);
+	max_entries = tmp;
+
+	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
+		max_entries = dev->ctrl.hmmaxd;
+
+	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
+			&descs_dma, GFP_KERNEL);
+	if (!descs)
+		goto out;
+
+	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
+	if (!bufs)
+		goto out_free_descs;
+
+	for (size = 0; size < preferred && i < max_entries; size += len) {
+		dma_addr_t dma_addr;
+
+		len = min_t(u64, chunk_size, preferred - size);
+		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
+				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
+		if (!bufs[i])
+			break;
+
+		descs[i].addr = cpu_to_le64(dma_addr);
+		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
+		i++;
+	}
+
+	if (!size)
+		goto out_free_bufs;
+
+	dev->nr_host_mem_descs = i;
+	dev->host_mem_size = size;
+	dev->host_mem_descs = descs;
+	dev->host_mem_descs_dma = descs_dma;
+	dev->host_mem_desc_bufs = bufs;
+	return 0;
+
+out_free_bufs:
+	while (--i >= 0) {
+		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
+
+		dma_free_attrs(dev->dev, size, bufs[i],
+			       le64_to_cpu(descs[i].addr),
+			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
+	}
+
+	kfree(bufs);
+out_free_descs:
+	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
+			descs_dma);
+out:
+	dev->host_mem_descs = NULL;
+	return -ENOMEM;
+}
+
+static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
+{
+	u32 chunk_size;
+
+	/* start big and work our way down */
+	for (chunk_size = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
+	     chunk_size >= max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
+	     chunk_size /= 2) {
+		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
+			if (!min || dev->host_mem_size >= min)
+				return 0;
+			nvme_free_host_mem(dev);
+		}
+	}
+
+	return -ENOMEM;
+}
+
+static int nvme_setup_host_mem(struct nvme_dev *dev)
+{
+	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
+	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
+	u64 min = (u64)dev->ctrl.hmmin * 4096;
+	u32 enable_bits = NVME_HOST_MEM_ENABLE;
+	int ret;
+
+	preferred = min(preferred, max);
+	if (min > max) {
+		dev_warn(dev->ctrl.device,
+			"min host memory (%lld MiB) above limit (%d MiB).\n",
+			min >> ilog2(SZ_1M), max_host_mem_size_mb);
+		nvme_free_host_mem(dev);
+		return 0;
+	}
+
+	/*
+	 * If we already have a buffer allocated check if we can reuse it.
+	 */
+	if (dev->host_mem_descs) {
+		if (dev->host_mem_size >= min)
+			enable_bits |= NVME_HOST_MEM_RETURN;
+		else
+			nvme_free_host_mem(dev);
+	}
+
+	if (!dev->host_mem_descs) {
+		if (nvme_alloc_host_mem(dev, min, preferred)) {
+			dev_warn(dev->ctrl.device,
+				"failed to allocate host memory buffer.\n");
+			return 0; /* controller must work without HMB */
+		}
+
+		dev_info(dev->ctrl.device,
+			"allocated %lld MiB host memory buffer.\n",
+			dev->host_mem_size >> ilog2(SZ_1M));
+	}
+
+	ret = nvme_set_host_mem(dev, enable_bits);
+	if (ret)
+		nvme_free_host_mem(dev);
+	return ret;
+}
+
+static int nvme_setup_io_queues(struct nvme_dev *dev)
+{
+	struct nvme_queue *adminq = &dev->queues[0];
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	int result, nr_io_queues;
+	unsigned long size;
+
+	struct irq_affinity affd = {
+		.pre_vectors = 1
+	};
+
+	nr_io_queues = num_possible_cpus();
+	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
+	if (result < 0)
+		return result;
+
+	if (nr_io_queues == 0)
+		return 0;
+
+	if (dev->cmb && (dev->cmbsz & NVME_CMBSZ_SQS)) {
+		result = nvme_cmb_qdepth(dev, nr_io_queues,
+				sizeof(struct nvme_command));
+		if (result > 0)
+			dev->q_depth = result;
+		else
+			nvme_release_cmb(dev);
+	}
+
+	do {
+		size = db_bar_size(dev, nr_io_queues);
+		result = nvme_remap_bar(dev, size);
+		if (!result)
+			break;
+		if (!--nr_io_queues)
+			return -ENOMEM;
+	} while (1);
+	adminq->q_db = dev->dbs;
+
+	/* Deregister the admin queue's interrupt */
+	pci_free_irq(pdev, 0, adminq);
+
+	/*
+	 * If we enable msix early due to not intx, disable it again before
+	 * setting up the full range we need.
+	 */
+	pci_free_irq_vectors(pdev);
+	result = pci_alloc_irq_vectors_affinity(pdev, 1, nr_io_queues + 1,
+			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
+	if (result <= 0)
+		return -EIO;
+	dev->num_vecs = result;
+	dev->max_qid = max(result - 1, 1);
+
+	/*
+	 * Should investigate if there's a performance win from allocating
+	 * more queues than interrupt vectors; it might allow the submission
+	 * path to scale better, even if the receive path is limited by the
+	 * number of interrupts.
+	 */
+
+	result = queue_request_irq(adminq);
+	if (result) {
+		adminq->cq_vector = -1;
+		return result;
+	}
+	return nvme_create_io_queues(dev);
+}
+
+static void nvme_del_queue_end(struct request *req, blk_status_t error)
+{
+	struct nvme_queue *nvmeq = req->end_io_data;
+
+	blk_mq_free_request(req);
+	complete(&nvmeq->dev->ioq_wait);
+}
+
+static void nvme_del_cq_end(struct request *req, blk_status_t error)
+{
+	struct nvme_queue *nvmeq = req->end_io_data;
+	u16 start, end;
+
+	if (!error) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&nvmeq->cq_lock, flags);
+		nvme_process_cq(nvmeq, &start, &end, -1);
+		spin_unlock_irqrestore(&nvmeq->cq_lock, flags);
+
+		nvme_complete_cqes(nvmeq, start, end);
+	}
+
+	nvme_del_queue_end(req, error);
+}
+
+static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
+{
+	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
+	struct request *req;
+	struct nvme_command cmd;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.delete_queue.opcode = opcode;
+	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
+
+	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	req->timeout = ADMIN_TIMEOUT;
+	req->end_io_data = nvmeq;
+
+	blk_execute_rq_nowait(q, NULL, req, false,
+			opcode == nvme_admin_delete_cq ?
+				nvme_del_cq_end : nvme_del_queue_end);
+	return 0;
+}
+
+static void nvme_disable_io_queues(struct nvme_dev *dev)
+{
+	int pass, queues = dev->online_queues - 1;
+	unsigned long timeout;
+	u8 opcode = nvme_admin_delete_sq;
+
+	for (pass = 0; pass < 2; pass++) {
+		int sent = 0, i = queues;
+
+		reinit_completion(&dev->ioq_wait);
+ retry:
+		timeout = ADMIN_TIMEOUT;
+		for (; i > 0; i--, sent++)
+			if (nvme_delete_queue(&dev->queues[i], opcode))
+				break;
+
+		while (sent--) {
+			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
+			if (timeout == 0)
+				return;
+			if (i)
+				goto retry;
+		}
+		opcode = nvme_admin_delete_cq;
+	}
+}
+
+/*
+ * return error value only when tagset allocation failed
+ */
+static int nvme_dev_add(struct nvme_dev *dev)
+{
+	int ret;
+
+	if (!dev->ctrl.tagset) {
+		dev->tagset.ops = &nvme_mq_ops;
+		dev->tagset.nr_hw_queues = dev->online_queues - 1;
+		dev->tagset.timeout = NVME_IO_TIMEOUT;
+		dev->tagset.numa_node = dev_to_node(dev->dev);
+		dev->tagset.queue_depth =
+				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
+		dev->tagset.cmd_size = nvme_pci_cmd_size(dev, false);
+		if ((dev->ctrl.sgls & ((1 << 0) | (1 << 1))) && sgl_threshold) {
+			dev->tagset.cmd_size = max(dev->tagset.cmd_size,
+					nvme_pci_cmd_size(dev, true));
+		}
+		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
+		dev->tagset.driver_data = dev;
+
+		ret = blk_mq_alloc_tag_set(&dev->tagset);
+		if (ret) {
+			dev_warn(dev->ctrl.device,
+				"IO queues tagset allocation failed %d\n", ret);
+			return ret;
+		}
+		dev->ctrl.tagset = &dev->tagset;
+
+		nvme_dbbuf_set(dev);
+	} else {
+		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
+
+		/* Free previously allocated queues that are no longer usable */
+		nvme_free_queues(dev, dev->online_queues);
+	}
+
+	return 0;
+}
+
+static int nvme_pci_enable(struct nvme_dev *dev)
+{
+	int result = -ENOMEM;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	if (pci_enable_device_mem(pdev))
+		return result;
+
+	pci_set_master(pdev);
+
+	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
+	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
+		goto disable;
+
+	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
+		result = -ENODEV;
+		goto disable;
+	}
+
+	/*
+	 * Some devices and/or platforms don't advertise or work with INTx
+	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
+	 * adjust this later.
+	 */
+	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+	if (result < 0)
+		return result;
+
+	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
+
+	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
+				io_queue_depth);
+	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
+	dev->dbs = dev->bar + 4096;
+
+	/*
+	 * Temporary fix for the Apple controller found in the MacBook8,1 and
+	 * some MacBook7,1 to avoid controller resets and data loss.
+	 */
+	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
+		dev->q_depth = 2;
+		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
+			"set queue depth=%u to work around controller resets\n",
+			dev->q_depth);
+	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
+		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
+		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
+		dev->q_depth = 64;
+		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
+                        "set queue depth=%u\n", dev->q_depth);
+	}
+
+	nvme_map_cmb(dev);
+
+	pci_enable_pcie_error_reporting(pdev);
+	pci_save_state(pdev);
+	return 0;
+
+ disable:
+	pci_disable_device(pdev);
+	return result;
+}
+
+static void nvme_dev_unmap(struct nvme_dev *dev)
+{
+	if (dev->bar)
+		iounmap(dev->bar);
+	pci_release_mem_regions(to_pci_dev(dev->dev));
+}
+
+static void nvme_pci_disable(struct nvme_dev *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	pci_free_irq_vectors(pdev);
+
+	if (pci_is_enabled(pdev)) {
+		pci_disable_pcie_error_reporting(pdev);
+		pci_disable_device(pdev);
+	}
+}
+
+static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
+{
+	int i;
+	bool dead = true;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	mutex_lock(&dev->shutdown_lock);
+	if (pci_is_enabled(pdev)) {
+		u32 csts = readl(dev->bar + NVME_REG_CSTS);
+
+		if (dev->ctrl.state == NVME_CTRL_LIVE ||
+		    dev->ctrl.state == NVME_CTRL_RESETTING)
+			nvme_start_freeze(&dev->ctrl);
+		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
+			pdev->error_state  != pci_channel_io_normal);
+	}
+
+	/*
+	 * Give the controller a chance to complete all entered requests if
+	 * doing a safe shutdown.
+	 */
+	if (!dead) {
+		if (shutdown)
+			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
+	}
+
+	nvme_stop_queues(&dev->ctrl);
+
+	if (!dead && dev->ctrl.queue_count > 0) {
+		nvme_disable_io_queues(dev);
+		nvme_disable_admin_queue(dev, shutdown);
+	}
+	for (i = dev->ctrl.queue_count - 1; i >= 0; i--)
+		nvme_suspend_queue(&dev->queues[i]);
+
+	nvme_pci_disable(dev);
+
+	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
+	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
+
+	/*
+	 * The driver will not be starting up queues again if shutting down so
+	 * must flush all entered requests to their failed completion to avoid
+	 * deadlocking blk-mq hot-cpu notifier.
+	 */
+	if (shutdown) {
+		nvme_start_queues(&dev->ctrl);
+		if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q))
+			blk_mq_unquiesce_queue(dev->ctrl.admin_q);
+	}
+	mutex_unlock(&dev->shutdown_lock);
+}
+
+static int nvme_setup_prp_pools(struct nvme_dev *dev)
+{
+	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
+						PAGE_SIZE, PAGE_SIZE, 0);
+	if (!dev->prp_page_pool)
+		return -ENOMEM;
+
+	/* Optimisation for I/Os between 4k and 128k */
+	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
+						256, 256, 0);
+	if (!dev->prp_small_pool) {
+		dma_pool_destroy(dev->prp_page_pool);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static void nvme_release_prp_pools(struct nvme_dev *dev)
+{
+	dma_pool_destroy(dev->prp_page_pool);
+	dma_pool_destroy(dev->prp_small_pool);
+}
+
+static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
+{
+	struct nvme_dev *dev = to_nvme_dev(ctrl);
+
+	nvme_dbbuf_dma_free(dev);
+	put_device(dev->dev);
+	if (dev->tagset.tags)
+		blk_mq_free_tag_set(&dev->tagset);
+	if (dev->ctrl.admin_q)
+		blk_put_queue(dev->ctrl.admin_q);
+	kfree(dev->queues);
+	free_opal_dev(dev->ctrl.opal_dev);
+	mempool_destroy(dev->iod_mempool);
+	kfree(dev);
+}
+
+static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
+{
+	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
+
+	nvme_get_ctrl(&dev->ctrl);
+	nvme_dev_disable(dev, false);
+	nvme_kill_queues(&dev->ctrl);
+	if (!queue_work(nvme_wq, &dev->remove_work))
+		nvme_put_ctrl(&dev->ctrl);
+}
+
+static void nvme_reset_work(struct work_struct *work)
+{
+	struct nvme_dev *dev =
+		container_of(work, struct nvme_dev, ctrl.reset_work);
+	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
+	int result;
+	enum nvme_ctrl_state new_state = NVME_CTRL_LIVE;
+
+	if (dev->ctrl.state != NVME_CTRL_RESETTING) {
+		dev_warn(dev->ctrl.device, "ctrl state %d is not RESETTING\n",
+			 dev->ctrl.state);
+		result = -ENODEV;
+		goto out;
+	}
+
+	/*
+	 * If we're called to reset a live controller first shut it down before
+	 * moving on.
+	 */
+	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
+		nvme_dev_disable(dev, false);
+
+	mutex_lock(&dev->shutdown_lock);
+	result = nvme_pci_enable(dev);
+	if (result)
+		goto out_unlock;
+
+	result = nvme_pci_configure_admin_queue(dev);
+	if (result)
+		goto out_unlock;
+
+	result = nvme_alloc_admin_tags(dev);
+	if (result)
+		goto out_unlock;
+
+	/*
+	 * Limit the max command size to prevent iod->sg allocations going
+	 * over a single page.
+	 */
+	dev->ctrl.max_hw_sectors = NVME_MAX_KB_SZ << 1;
+	dev->ctrl.max_segments = NVME_MAX_SEGS;
+	mutex_unlock(&dev->shutdown_lock);
+
+	/*
+	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
+	 * initializing procedure here.
+	 */
+	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
+		dev_warn(dev->ctrl.device,
+			"failed to mark controller CONNECTING\n");
+		result = -EBUSY;
+		goto out;
+	}
+
+	result = nvme_init_identify(&dev->ctrl);
+	if (result)
+		goto out;
+
+	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
+		if (!dev->ctrl.opal_dev)
+			dev->ctrl.opal_dev =
+				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
+		else if (was_suspend)
+			opal_unlock_from_suspend(dev->ctrl.opal_dev);
+	} else {
+		free_opal_dev(dev->ctrl.opal_dev);
+		dev->ctrl.opal_dev = NULL;
+	}
+
+	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
+		result = nvme_dbbuf_dma_alloc(dev);
+		if (result)
+			dev_warn(dev->dev,
+				 "unable to allocate dma for dbbuf\n");
+	}
+
+	if (dev->ctrl.hmpre) {
+		result = nvme_setup_host_mem(dev);
+		if (result < 0)
+			goto out;
+	}
+
+	result = nvme_setup_io_queues(dev);
+	if (result)
+		goto out;
+
+	/*
+	 * Keep the controller around but remove all namespaces if we don't have
+	 * any working I/O queue.
+	 */
+	if (dev->online_queues < 2) {
+		dev_warn(dev->ctrl.device, "IO queues not created\n");
+		nvme_kill_queues(&dev->ctrl);
+		nvme_remove_namespaces(&dev->ctrl);
+		new_state = NVME_CTRL_ADMIN_ONLY;
+	} else {
+		nvme_start_queues(&dev->ctrl);
+		nvme_wait_freeze(&dev->ctrl);
+		/* hit this only when allocate tagset fails */
+		if (nvme_dev_add(dev))
+			new_state = NVME_CTRL_ADMIN_ONLY;
+		nvme_unfreeze(&dev->ctrl);
+	}
+
+	/*
+	 * If only admin queue live, keep it to do further investigation or
+	 * recovery.
+	 */
+	if (!nvme_change_ctrl_state(&dev->ctrl, new_state)) {
+		dev_warn(dev->ctrl.device,
+			"failed to mark controller state %d\n", new_state);
+		result = -ENODEV;
+		goto out;
+	}
+
+	nvme_start_ctrl(&dev->ctrl);
+	return;
+
+ out_unlock:
+	mutex_unlock(&dev->shutdown_lock);
+ out:
+	nvme_remove_dead_ctrl(dev, result);
+}
+
+static void nvme_remove_dead_ctrl_work(struct work_struct *work)
+{
+	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	if (pci_get_drvdata(pdev))
+		device_release_driver(&pdev->dev);
+	nvme_put_ctrl(&dev->ctrl);
+}
+
+static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
+{
+	*val = readl(to_nvme_dev(ctrl)->bar + off);
+	return 0;
+}
+
+static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
+{
+	writel(val, to_nvme_dev(ctrl)->bar + off);
+	return 0;
+}
+
+static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
+{
+	*val = lo_hi_readq(to_nvme_dev(ctrl)->bar + off);
+	return 0;
+}
+
+static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
+{
+	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
+
+	return snprintf(buf, size, "%s", dev_name(&pdev->dev));
+}
+
+static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
+	.name			= "pcie",
+	.module			= THIS_MODULE,
+	.flags			= NVME_F_METADATA_SUPPORTED,
+	.reg_read32		= nvme_pci_reg_read32,
+	.reg_write32		= nvme_pci_reg_write32,
+	.reg_read64		= nvme_pci_reg_read64,
+	.free_ctrl		= nvme_pci_free_ctrl,
+	.submit_async_event	= nvme_pci_submit_async_event,
+	.get_address		= nvme_pci_get_address,
+};
+
+static int nvme_dev_map(struct nvme_dev *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	if (pci_request_mem_regions(pdev, "nvme"))
+		return -ENODEV;
+
+	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
+		goto release;
+
+	return 0;
+  release:
+	pci_release_mem_regions(pdev);
+	return -ENODEV;
+}
+
+static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
+{
+	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
+		/*
+		 * Several Samsung devices seem to drop off the PCIe bus
+		 * randomly when APST is on and uses the deepest sleep state.
+		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
+		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
+		 * 950 PRO 256GB", but it seems to be restricted to two Dell
+		 * laptops.
+		 */
+		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
+		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
+		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
+			return NVME_QUIRK_NO_DEEPEST_PS;
+	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
+		/*
+		 * Samsung SSD 960 EVO drops off the PCIe bus after system
+		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
+		 * within few minutes after bootup on a Coffee Lake board -
+		 * ASUS PRIME Z370-A
+		 */
+		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
+		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
+		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
+			return NVME_QUIRK_NO_APST;
+	}
+
+	return 0;
+}
+
+static void nvme_async_probe(void *data, async_cookie_t cookie)
+{
+	struct nvme_dev *dev = data;
+
+	flush_work(&dev->ctrl.reset_work);
+	flush_work(&dev->ctrl.scan_work);
+	nvme_put_ctrl(&dev->ctrl);
+}
+
+static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	int node, result = -ENOMEM;
+	struct nvme_dev *dev;
+	unsigned long quirks = id->driver_data;
+	size_t alloc_size;
+
+	node = dev_to_node(&pdev->dev);
+	if (node == NUMA_NO_NODE)
+		set_dev_node(&pdev->dev, first_memory_node);
+
+	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
+	if (!dev)
+		return -ENOMEM;
+
+	dev->queues = kcalloc_node(num_possible_cpus() + 1,
+			sizeof(struct nvme_queue), GFP_KERNEL, node);
+	if (!dev->queues)
+		goto free;
+
+	dev->dev = get_device(&pdev->dev);
+	pci_set_drvdata(pdev, dev);
+
+	result = nvme_dev_map(dev);
+	if (result)
+		goto put_pci;
+
+	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
+	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
+	mutex_init(&dev->shutdown_lock);
+	init_completion(&dev->ioq_wait);
+
+	result = nvme_setup_prp_pools(dev);
+	if (result)
+		goto unmap;
+
+	quirks |= check_vendor_combination_bug(pdev);
+
+	/*
+	 * Double check that our mempool alloc size will cover the biggest
+	 * command we support.
+	 */
+	alloc_size = nvme_pci_iod_alloc_size(dev, NVME_MAX_KB_SZ,
+						NVME_MAX_SEGS, true);
+	WARN_ON_ONCE(alloc_size > PAGE_SIZE);
+
+	dev->iod_mempool = mempool_create_node(1, mempool_kmalloc,
+						mempool_kfree,
+						(void *) alloc_size,
+						GFP_KERNEL, node);
+	if (!dev->iod_mempool) {
+		result = -ENOMEM;
+		goto release_pools;
+	}
+
+	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
+			quirks);
+	if (result)
+		goto release_mempool;
+
+	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
+
+	nvme_reset_ctrl(&dev->ctrl);
+	nvme_get_ctrl(&dev->ctrl);
+	async_schedule(nvme_async_probe, dev);
+
+	return 0;
+
+ release_mempool:
+	mempool_destroy(dev->iod_mempool);
+ release_pools:
+	nvme_release_prp_pools(dev);
+ unmap:
+	nvme_dev_unmap(dev);
+ put_pci:
+	put_device(dev->dev);
+ free:
+	kfree(dev->queues);
+	kfree(dev);
+	return result;
+}
+
+static void nvme_reset_prepare(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+	nvme_dev_disable(dev, false);
+}
+
+static void nvme_reset_done(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+	nvme_reset_ctrl_sync(&dev->ctrl);
+}
+
+static void nvme_shutdown(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+	nvme_dev_disable(dev, true);
+}
+
+/*
+ * The driver's remove may be called on a device in a partially initialized
+ * state. This function must not have any dependencies on the device state in
+ * order to proceed.
+ */
+static void nvme_remove(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+
+	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
+	pci_set_drvdata(pdev, NULL);
+
+	if (!pci_device_is_present(pdev)) {
+		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
+		nvme_dev_disable(dev, true);
+	}
+
+	flush_work(&dev->ctrl.reset_work);
+	nvme_stop_ctrl(&dev->ctrl);
+	nvme_remove_namespaces(&dev->ctrl);
+	nvme_dev_disable(dev, true);
+	nvme_release_cmb(dev);
+	nvme_free_host_mem(dev);
+	nvme_dev_remove_admin(dev);
+	nvme_free_queues(dev, 0);
+	nvme_uninit_ctrl(&dev->ctrl);
+	nvme_release_prp_pools(dev);
+	nvme_dev_unmap(dev);
+	nvme_put_ctrl(&dev->ctrl);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int nvme_suspend(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct nvme_dev *ndev = pci_get_drvdata(pdev);
+
+	nvme_dev_disable(ndev, true);
+	return 0;
+}
+
+static int nvme_resume(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct nvme_dev *ndev = pci_get_drvdata(pdev);
+
+	nvme_reset_ctrl(&ndev->ctrl);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
+
+static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
+						pci_channel_state_t state)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+
+	/*
+	 * A frozen channel requires a reset. When detected, this method will
+	 * shutdown the controller to quiesce. The controller will be restarted
+	 * after the slot reset through driver's slot_reset callback.
+	 */
+	switch (state) {
+	case pci_channel_io_normal:
+		return PCI_ERS_RESULT_CAN_RECOVER;
+	case pci_channel_io_frozen:
+		dev_warn(dev->ctrl.device,
+			"frozen state error detected, reset controller\n");
+		nvme_dev_disable(dev, false);
+		return PCI_ERS_RESULT_NEED_RESET;
+	case pci_channel_io_perm_failure:
+		dev_warn(dev->ctrl.device,
+			"failure state error detected, request disconnect\n");
+		return PCI_ERS_RESULT_DISCONNECT;
+	}
+	return PCI_ERS_RESULT_NEED_RESET;
+}
+
+static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+
+	dev_info(dev->ctrl.device, "restart after slot reset\n");
+	pci_restore_state(pdev);
+	nvme_reset_ctrl(&dev->ctrl);
+	return PCI_ERS_RESULT_RECOVERED;
+}
+
+static void nvme_error_resume(struct pci_dev *pdev)
+{
+	struct nvme_dev *dev = pci_get_drvdata(pdev);
+
+	flush_work(&dev->ctrl.reset_work);
+	pci_cleanup_aer_uncorrect_error_status(pdev);
+}
+
+static const struct pci_error_handlers nvme_err_handler = {
+	.error_detected	= nvme_error_detected,
+	.slot_reset	= nvme_slot_reset,
+	.resume		= nvme_error_resume,
+	.reset_prepare	= nvme_reset_prepare,
+	.reset_done	= nvme_reset_done,
+};
+
+static const struct pci_device_id nvme_id_table[] = {
+	{ PCI_VDEVICE(INTEL, 0x0953),
+		.driver_data = NVME_QUIRK_STRIPE_SIZE |
+				NVME_QUIRK_DEALLOCATE_ZEROES, },
+	{ PCI_VDEVICE(INTEL, 0x0a53),
+		.driver_data = NVME_QUIRK_STRIPE_SIZE |
+				NVME_QUIRK_DEALLOCATE_ZEROES, },
+	{ PCI_VDEVICE(INTEL, 0x0a54),
+		.driver_data = NVME_QUIRK_STRIPE_SIZE |
+				NVME_QUIRK_DEALLOCATE_ZEROES, },
+	{ PCI_VDEVICE(INTEL, 0x0a55),
+		.driver_data = NVME_QUIRK_STRIPE_SIZE |
+				NVME_QUIRK_DEALLOCATE_ZEROES, },
+	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
+		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
+				NVME_QUIRK_MEDIUM_PRIO_SQ },
+	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
+		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
+	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
+		.driver_data = NVME_QUIRK_LIGHTNVM, },
+	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
+		.driver_data = NVME_QUIRK_LIGHTNVM, },
+	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
+		.driver_data = NVME_QUIRK_LIGHTNVM, },
+	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
+	{ PCI_DEVICE(0x2646, 0x2263),   /* KINGSTON A2000 NVMe SSD  */
+		.driver_data = NVME_QUIRK_NO_DEEPEST_PS, },
+	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, nvme_id_table);
+
+static struct pci_driver nvme_driver = {
+	.name		= "nvme",
+	.id_table	= nvme_id_table,
+	.probe		= nvme_probe,
+	.remove		= nvme_remove,
+	.shutdown	= nvme_shutdown,
+	.driver		= {
+		.pm	= &nvme_dev_pm_ops,
+	},
+	.sriov_configure = pci_sriov_configure_simple,
+	.err_handler	= &nvme_err_handler,
+};
+
+static int __init nvme_init(void)
+{
+	return pci_register_driver(&nvme_driver);
+}
+
+static void __exit nvme_exit(void)
+{
+	pci_unregister_driver(&nvme_driver);
+	flush_workqueue(nvme_wq);
+	_nvme_check_size();
+}
+
+MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0");
+module_init(nvme_init);
+module_exit(nvme_exit);
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
new file mode 100644
index 000000000..55f499952
--- /dev/null
+++ b/drivers/nvme/host/rdma.c
@@ -0,0 +1,2121 @@
+/*
+ * NVMe over Fabrics RDMA host code.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <rdma/mr_pool.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/atomic.h>
+#include <linux/blk-mq.h>
+#include <linux/blk-mq-rdma.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/scatterlist.h>
+#include <linux/nvme.h>
+#include <asm/unaligned.h>
+
+#include <rdma/ib_verbs.h>
+#include <rdma/rdma_cm.h>
+#include <linux/nvme-rdma.h>
+
+#include "nvme.h"
+#include "fabrics.h"
+
+
+#define NVME_RDMA_CONNECT_TIMEOUT_MS	3000		/* 3 second */
+
+#define NVME_RDMA_MAX_SEGMENTS		256
+
+#define NVME_RDMA_MAX_INLINE_SEGMENTS	4
+
+struct nvme_rdma_device {
+	struct ib_device	*dev;
+	struct ib_pd		*pd;
+	struct kref		ref;
+	struct list_head	entry;
+	unsigned int		num_inline_segments;
+};
+
+struct nvme_rdma_qe {
+	struct ib_cqe		cqe;
+	void			*data;
+	u64			dma;
+};
+
+struct nvme_rdma_queue;
+struct nvme_rdma_request {
+	struct nvme_request	req;
+	struct ib_mr		*mr;
+	struct nvme_rdma_qe	sqe;
+	union nvme_result	result;
+	__le16			status;
+	refcount_t		ref;
+	struct ib_sge		sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS];
+	u32			num_sge;
+	int			nents;
+	struct ib_reg_wr	reg_wr;
+	struct ib_cqe		reg_cqe;
+	struct nvme_rdma_queue  *queue;
+	struct sg_table		sg_table;
+	struct scatterlist	first_sgl[];
+};
+
+enum nvme_rdma_queue_flags {
+	NVME_RDMA_Q_ALLOCATED		= 0,
+	NVME_RDMA_Q_LIVE		= 1,
+	NVME_RDMA_Q_TR_READY		= 2,
+};
+
+struct nvme_rdma_queue {
+	struct nvme_rdma_qe	*rsp_ring;
+	int			queue_size;
+	size_t			cmnd_capsule_len;
+	struct nvme_rdma_ctrl	*ctrl;
+	struct nvme_rdma_device	*device;
+	struct ib_cq		*ib_cq;
+	struct ib_qp		*qp;
+
+	unsigned long		flags;
+	struct rdma_cm_id	*cm_id;
+	int			cm_error;
+	struct completion	cm_done;
+};
+
+struct nvme_rdma_ctrl {
+	/* read only in the hot path */
+	struct nvme_rdma_queue	*queues;
+
+	/* other member variables */
+	struct blk_mq_tag_set	tag_set;
+	struct work_struct	err_work;
+
+	struct nvme_rdma_qe	async_event_sqe;
+
+	struct delayed_work	reconnect_work;
+
+	struct list_head	list;
+
+	struct blk_mq_tag_set	admin_tag_set;
+	struct nvme_rdma_device	*device;
+
+	u32			max_fr_pages;
+
+	struct sockaddr_storage addr;
+	struct sockaddr_storage src_addr;
+
+	struct nvme_ctrl	ctrl;
+	struct mutex		teardown_lock;
+	bool			use_inline_data;
+};
+
+static inline struct nvme_rdma_ctrl *to_rdma_ctrl(struct nvme_ctrl *ctrl)
+{
+	return container_of(ctrl, struct nvme_rdma_ctrl, ctrl);
+}
+
+static LIST_HEAD(device_list);
+static DEFINE_MUTEX(device_list_mutex);
+
+static LIST_HEAD(nvme_rdma_ctrl_list);
+static DEFINE_MUTEX(nvme_rdma_ctrl_mutex);
+
+/*
+ * Disabling this option makes small I/O goes faster, but is fundamentally
+ * unsafe.  With it turned off we will have to register a global rkey that
+ * allows read and write access to all physical memory.
+ */
+static bool register_always = true;
+module_param(register_always, bool, 0444);
+MODULE_PARM_DESC(register_always,
+	 "Use memory registration even for contiguous memory regions");
+
+static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
+		struct rdma_cm_event *event);
+static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
+
+static const struct blk_mq_ops nvme_rdma_mq_ops;
+static const struct blk_mq_ops nvme_rdma_admin_mq_ops;
+
+/* XXX: really should move to a generic header sooner or later.. */
+static inline void put_unaligned_le24(u32 val, u8 *p)
+{
+	*p++ = val;
+	*p++ = val >> 8;
+	*p++ = val >> 16;
+}
+
+static inline int nvme_rdma_queue_idx(struct nvme_rdma_queue *queue)
+{
+	return queue - queue->ctrl->queues;
+}
+
+static inline size_t nvme_rdma_inline_data_size(struct nvme_rdma_queue *queue)
+{
+	return queue->cmnd_capsule_len - sizeof(struct nvme_command);
+}
+
+static void nvme_rdma_free_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
+		size_t capsule_size, enum dma_data_direction dir)
+{
+	ib_dma_unmap_single(ibdev, qe->dma, capsule_size, dir);
+	kfree(qe->data);
+}
+
+static int nvme_rdma_alloc_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
+		size_t capsule_size, enum dma_data_direction dir)
+{
+	qe->data = kzalloc(capsule_size, GFP_KERNEL);
+	if (!qe->data)
+		return -ENOMEM;
+
+	qe->dma = ib_dma_map_single(ibdev, qe->data, capsule_size, dir);
+	if (ib_dma_mapping_error(ibdev, qe->dma)) {
+		kfree(qe->data);
+		qe->data = NULL;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void nvme_rdma_free_ring(struct ib_device *ibdev,
+		struct nvme_rdma_qe *ring, size_t ib_queue_size,
+		size_t capsule_size, enum dma_data_direction dir)
+{
+	int i;
+
+	for (i = 0; i < ib_queue_size; i++)
+		nvme_rdma_free_qe(ibdev, &ring[i], capsule_size, dir);
+	kfree(ring);
+}
+
+static struct nvme_rdma_qe *nvme_rdma_alloc_ring(struct ib_device *ibdev,
+		size_t ib_queue_size, size_t capsule_size,
+		enum dma_data_direction dir)
+{
+	struct nvme_rdma_qe *ring;
+	int i;
+
+	ring = kcalloc(ib_queue_size, sizeof(struct nvme_rdma_qe), GFP_KERNEL);
+	if (!ring)
+		return NULL;
+
+	for (i = 0; i < ib_queue_size; i++) {
+		if (nvme_rdma_alloc_qe(ibdev, &ring[i], capsule_size, dir))
+			goto out_free_ring;
+	}
+
+	return ring;
+
+out_free_ring:
+	nvme_rdma_free_ring(ibdev, ring, i, capsule_size, dir);
+	return NULL;
+}
+
+static void nvme_rdma_qp_event(struct ib_event *event, void *context)
+{
+	pr_debug("QP event %s (%d)\n",
+		 ib_event_msg(event->event), event->event);
+
+}
+
+static int nvme_rdma_wait_for_cm(struct nvme_rdma_queue *queue)
+{
+	wait_for_completion_interruptible_timeout(&queue->cm_done,
+			msecs_to_jiffies(NVME_RDMA_CONNECT_TIMEOUT_MS) + 1);
+	return queue->cm_error;
+}
+
+static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor)
+{
+	struct nvme_rdma_device *dev = queue->device;
+	struct ib_qp_init_attr init_attr;
+	int ret;
+
+	memset(&init_attr, 0, sizeof(init_attr));
+	init_attr.event_handler = nvme_rdma_qp_event;
+	/* +1 for drain */
+	init_attr.cap.max_send_wr = factor * queue->queue_size + 1;
+	/* +1 for drain */
+	init_attr.cap.max_recv_wr = queue->queue_size + 1;
+	init_attr.cap.max_recv_sge = 1;
+	init_attr.cap.max_send_sge = 1 + dev->num_inline_segments;
+	init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+	init_attr.qp_type = IB_QPT_RC;
+	init_attr.send_cq = queue->ib_cq;
+	init_attr.recv_cq = queue->ib_cq;
+
+	ret = rdma_create_qp(queue->cm_id, dev->pd, &init_attr);
+
+	queue->qp = queue->cm_id->qp;
+	return ret;
+}
+
+static void nvme_rdma_exit_request(struct blk_mq_tag_set *set,
+		struct request *rq, unsigned int hctx_idx)
+{
+	struct nvme_rdma_ctrl *ctrl = set->driver_data;
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
+	struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
+	struct nvme_rdma_device *dev = queue->device;
+
+	nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
+			DMA_TO_DEVICE);
+}
+
+static int nvme_rdma_init_request(struct blk_mq_tag_set *set,
+		struct request *rq, unsigned int hctx_idx,
+		unsigned int numa_node)
+{
+	struct nvme_rdma_ctrl *ctrl = set->driver_data;
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
+	struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
+	struct nvme_rdma_device *dev = queue->device;
+	struct ib_device *ibdev = dev->dev;
+	int ret;
+
+	nvme_req(rq)->ctrl = &ctrl->ctrl;
+	ret = nvme_rdma_alloc_qe(ibdev, &req->sqe, sizeof(struct nvme_command),
+			DMA_TO_DEVICE);
+	if (ret)
+		return ret;
+
+	req->queue = queue;
+
+	return 0;
+}
+
+static int nvme_rdma_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_rdma_ctrl *ctrl = data;
+	struct nvme_rdma_queue *queue = &ctrl->queues[hctx_idx + 1];
+
+	BUG_ON(hctx_idx >= ctrl->ctrl.queue_count);
+
+	hctx->driver_data = queue;
+	return 0;
+}
+
+static int nvme_rdma_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_rdma_ctrl *ctrl = data;
+	struct nvme_rdma_queue *queue = &ctrl->queues[0];
+
+	BUG_ON(hctx_idx != 0);
+
+	hctx->driver_data = queue;
+	return 0;
+}
+
+static void nvme_rdma_free_dev(struct kref *ref)
+{
+	struct nvme_rdma_device *ndev =
+		container_of(ref, struct nvme_rdma_device, ref);
+
+	mutex_lock(&device_list_mutex);
+	list_del(&ndev->entry);
+	mutex_unlock(&device_list_mutex);
+
+	ib_dealloc_pd(ndev->pd);
+	kfree(ndev);
+}
+
+static void nvme_rdma_dev_put(struct nvme_rdma_device *dev)
+{
+	kref_put(&dev->ref, nvme_rdma_free_dev);
+}
+
+static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
+{
+	return kref_get_unless_zero(&dev->ref);
+}
+
+static struct nvme_rdma_device *
+nvme_rdma_find_get_device(struct rdma_cm_id *cm_id)
+{
+	struct nvme_rdma_device *ndev;
+
+	mutex_lock(&device_list_mutex);
+	list_for_each_entry(ndev, &device_list, entry) {
+		if (ndev->dev->node_guid == cm_id->device->node_guid &&
+		    nvme_rdma_dev_get(ndev))
+			goto out_unlock;
+	}
+
+	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
+	if (!ndev)
+		goto out_err;
+
+	ndev->dev = cm_id->device;
+	kref_init(&ndev->ref);
+
+	ndev->pd = ib_alloc_pd(ndev->dev,
+		register_always ? 0 : IB_PD_UNSAFE_GLOBAL_RKEY);
+	if (IS_ERR(ndev->pd))
+		goto out_free_dev;
+
+	if (!(ndev->dev->attrs.device_cap_flags &
+	      IB_DEVICE_MEM_MGT_EXTENSIONS)) {
+		dev_err(&ndev->dev->dev,
+			"Memory registrations not supported.\n");
+		goto out_free_pd;
+	}
+
+	ndev->num_inline_segments = min(NVME_RDMA_MAX_INLINE_SEGMENTS,
+					ndev->dev->attrs.max_send_sge - 1);
+	list_add(&ndev->entry, &device_list);
+out_unlock:
+	mutex_unlock(&device_list_mutex);
+	return ndev;
+
+out_free_pd:
+	ib_dealloc_pd(ndev->pd);
+out_free_dev:
+	kfree(ndev);
+out_err:
+	mutex_unlock(&device_list_mutex);
+	return NULL;
+}
+
+static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
+{
+	struct nvme_rdma_device *dev;
+	struct ib_device *ibdev;
+
+	if (!test_and_clear_bit(NVME_RDMA_Q_TR_READY, &queue->flags))
+		return;
+
+	dev = queue->device;
+	ibdev = dev->dev;
+
+	ib_mr_pool_destroy(queue->qp, &queue->qp->rdma_mrs);
+
+	/*
+	 * The cm_id object might have been destroyed during RDMA connection
+	 * establishment error flow to avoid getting other cma events, thus
+	 * the destruction of the QP shouldn't use rdma_cm API.
+	 */
+	ib_destroy_qp(queue->qp);
+	ib_free_cq(queue->ib_cq);
+
+	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
+			sizeof(struct nvme_completion), DMA_FROM_DEVICE);
+
+	nvme_rdma_dev_put(dev);
+}
+
+static int nvme_rdma_get_max_fr_pages(struct ib_device *ibdev)
+{
+	return min_t(u32, NVME_RDMA_MAX_SEGMENTS,
+		     ibdev->attrs.max_fast_reg_page_list_len);
+}
+
+static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
+{
+	struct ib_device *ibdev;
+	const int send_wr_factor = 3;			/* MR, SEND, INV */
+	const int cq_factor = send_wr_factor + 1;	/* + RECV */
+	int comp_vector, idx = nvme_rdma_queue_idx(queue);
+	int ret;
+
+	queue->device = nvme_rdma_find_get_device(queue->cm_id);
+	if (!queue->device) {
+		dev_err(queue->cm_id->device->dev.parent,
+			"no client data found!\n");
+		return -ECONNREFUSED;
+	}
+	ibdev = queue->device->dev;
+
+	/*
+	 * Spread I/O queues completion vectors according their queue index.
+	 * Admin queues can always go on completion vector 0.
+	 */
+	comp_vector = (idx == 0 ? idx : idx - 1) % ibdev->num_comp_vectors;
+
+	/* +1 for ib_stop_cq */
+	queue->ib_cq = ib_alloc_cq(ibdev, queue,
+				cq_factor * queue->queue_size + 1,
+				comp_vector, IB_POLL_SOFTIRQ);
+	if (IS_ERR(queue->ib_cq)) {
+		ret = PTR_ERR(queue->ib_cq);
+		goto out_put_dev;
+	}
+
+	ret = nvme_rdma_create_qp(queue, send_wr_factor);
+	if (ret)
+		goto out_destroy_ib_cq;
+
+	queue->rsp_ring = nvme_rdma_alloc_ring(ibdev, queue->queue_size,
+			sizeof(struct nvme_completion), DMA_FROM_DEVICE);
+	if (!queue->rsp_ring) {
+		ret = -ENOMEM;
+		goto out_destroy_qp;
+	}
+
+	ret = ib_mr_pool_init(queue->qp, &queue->qp->rdma_mrs,
+			      queue->queue_size,
+			      IB_MR_TYPE_MEM_REG,
+			      nvme_rdma_get_max_fr_pages(ibdev));
+	if (ret) {
+		dev_err(queue->ctrl->ctrl.device,
+			"failed to initialize MR pool sized %d for QID %d\n",
+			queue->queue_size, idx);
+		goto out_destroy_ring;
+	}
+
+	set_bit(NVME_RDMA_Q_TR_READY, &queue->flags);
+
+	return 0;
+
+out_destroy_ring:
+	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
+			    sizeof(struct nvme_completion), DMA_FROM_DEVICE);
+out_destroy_qp:
+	rdma_destroy_qp(queue->cm_id);
+out_destroy_ib_cq:
+	ib_free_cq(queue->ib_cq);
+out_put_dev:
+	nvme_rdma_dev_put(queue->device);
+	return ret;
+}
+
+static int nvme_rdma_alloc_queue(struct nvme_rdma_ctrl *ctrl,
+		int idx, size_t queue_size)
+{
+	struct nvme_rdma_queue *queue;
+	struct sockaddr *src_addr = NULL;
+	int ret;
+
+	queue = &ctrl->queues[idx];
+	queue->ctrl = ctrl;
+	init_completion(&queue->cm_done);
+
+	if (idx > 0)
+		queue->cmnd_capsule_len = ctrl->ctrl.ioccsz * 16;
+	else
+		queue->cmnd_capsule_len = sizeof(struct nvme_command);
+
+	queue->queue_size = queue_size;
+
+	queue->cm_id = rdma_create_id(&init_net, nvme_rdma_cm_handler, queue,
+			RDMA_PS_TCP, IB_QPT_RC);
+	if (IS_ERR(queue->cm_id)) {
+		dev_info(ctrl->ctrl.device,
+			"failed to create CM ID: %ld\n", PTR_ERR(queue->cm_id));
+		return PTR_ERR(queue->cm_id);
+	}
+
+	if (ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR)
+		src_addr = (struct sockaddr *)&ctrl->src_addr;
+
+	queue->cm_error = -ETIMEDOUT;
+	ret = rdma_resolve_addr(queue->cm_id, src_addr,
+			(struct sockaddr *)&ctrl->addr,
+			NVME_RDMA_CONNECT_TIMEOUT_MS);
+	if (ret) {
+		dev_info(ctrl->ctrl.device,
+			"rdma_resolve_addr failed (%d).\n", ret);
+		goto out_destroy_cm_id;
+	}
+
+	ret = nvme_rdma_wait_for_cm(queue);
+	if (ret) {
+		dev_info(ctrl->ctrl.device,
+			"rdma connection establishment failed (%d)\n", ret);
+		goto out_destroy_cm_id;
+	}
+
+	set_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags);
+
+	return 0;
+
+out_destroy_cm_id:
+	rdma_destroy_id(queue->cm_id);
+	nvme_rdma_destroy_queue_ib(queue);
+	return ret;
+}
+
+static void nvme_rdma_stop_queue(struct nvme_rdma_queue *queue)
+{
+	if (!test_and_clear_bit(NVME_RDMA_Q_LIVE, &queue->flags))
+		return;
+
+	rdma_disconnect(queue->cm_id);
+	ib_drain_qp(queue->qp);
+}
+
+static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue)
+{
+	if (!test_and_clear_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags))
+		return;
+
+	nvme_rdma_destroy_queue_ib(queue);
+	rdma_destroy_id(queue->cm_id);
+}
+
+static void nvme_rdma_free_io_queues(struct nvme_rdma_ctrl *ctrl)
+{
+	int i;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++)
+		nvme_rdma_free_queue(&ctrl->queues[i]);
+}
+
+static void nvme_rdma_stop_io_queues(struct nvme_rdma_ctrl *ctrl)
+{
+	int i;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++)
+		nvme_rdma_stop_queue(&ctrl->queues[i]);
+}
+
+static int nvme_rdma_start_queue(struct nvme_rdma_ctrl *ctrl, int idx)
+{
+	int ret;
+
+	if (idx)
+		ret = nvmf_connect_io_queue(&ctrl->ctrl, idx);
+	else
+		ret = nvmf_connect_admin_queue(&ctrl->ctrl);
+
+	if (!ret)
+		set_bit(NVME_RDMA_Q_LIVE, &ctrl->queues[idx].flags);
+	else
+		dev_info(ctrl->ctrl.device,
+			"failed to connect queue: %d ret=%d\n", idx, ret);
+	return ret;
+}
+
+static int nvme_rdma_start_io_queues(struct nvme_rdma_ctrl *ctrl)
+{
+	int i, ret = 0;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		ret = nvme_rdma_start_queue(ctrl, i);
+		if (ret)
+			goto out_stop_queues;
+	}
+
+	return 0;
+
+out_stop_queues:
+	for (i--; i >= 1; i--)
+		nvme_rdma_stop_queue(&ctrl->queues[i]);
+	return ret;
+}
+
+static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl)
+{
+	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
+	struct ib_device *ibdev = ctrl->device->dev;
+	unsigned int nr_io_queues;
+	int i, ret;
+
+	nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
+
+	/*
+	 * we map queues according to the device irq vectors for
+	 * optimal locality so we don't need more queues than
+	 * completion vectors.
+	 */
+	nr_io_queues = min_t(unsigned int, nr_io_queues,
+				ibdev->num_comp_vectors);
+
+	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
+	if (ret)
+		return ret;
+
+	if (nr_io_queues == 0) {
+		dev_err(ctrl->ctrl.device,
+			"unable to set any I/O queues\n");
+		return -ENOMEM;
+	}
+
+	ctrl->ctrl.queue_count = nr_io_queues + 1;
+	dev_info(ctrl->ctrl.device,
+		"creating %d I/O queues.\n", nr_io_queues);
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		ret = nvme_rdma_alloc_queue(ctrl, i,
+				ctrl->ctrl.sqsize + 1);
+		if (ret)
+			goto out_free_queues;
+	}
+
+	return 0;
+
+out_free_queues:
+	for (i--; i >= 1; i--)
+		nvme_rdma_free_queue(&ctrl->queues[i]);
+
+	return ret;
+}
+
+static void nvme_rdma_free_tagset(struct nvme_ctrl *nctrl,
+		struct blk_mq_tag_set *set)
+{
+	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
+
+	blk_mq_free_tag_set(set);
+	nvme_rdma_dev_put(ctrl->device);
+}
+
+static struct blk_mq_tag_set *nvme_rdma_alloc_tagset(struct nvme_ctrl *nctrl,
+		bool admin)
+{
+	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
+	struct blk_mq_tag_set *set;
+	int ret;
+
+	if (admin) {
+		set = &ctrl->admin_tag_set;
+		memset(set, 0, sizeof(*set));
+		set->ops = &nvme_rdma_admin_mq_ops;
+		set->queue_depth = NVME_AQ_MQ_TAG_DEPTH;
+		set->reserved_tags = 2; /* connect + keep-alive */
+		set->numa_node = NUMA_NO_NODE;
+		set->cmd_size = sizeof(struct nvme_rdma_request) +
+			SG_CHUNK_SIZE * sizeof(struct scatterlist);
+		set->driver_data = ctrl;
+		set->nr_hw_queues = 1;
+		set->timeout = ADMIN_TIMEOUT;
+		set->flags = BLK_MQ_F_NO_SCHED;
+	} else {
+		set = &ctrl->tag_set;
+		memset(set, 0, sizeof(*set));
+		set->ops = &nvme_rdma_mq_ops;
+		set->queue_depth = nctrl->sqsize + 1;
+		set->reserved_tags = 1; /* fabric connect */
+		set->numa_node = NUMA_NO_NODE;
+		set->flags = BLK_MQ_F_SHOULD_MERGE;
+		set->cmd_size = sizeof(struct nvme_rdma_request) +
+			SG_CHUNK_SIZE * sizeof(struct scatterlist);
+		set->driver_data = ctrl;
+		set->nr_hw_queues = nctrl->queue_count - 1;
+		set->timeout = NVME_IO_TIMEOUT;
+	}
+
+	ret = blk_mq_alloc_tag_set(set);
+	if (ret)
+		goto out;
+
+	/*
+	 * We need a reference on the device as long as the tag_set is alive,
+	 * as the MRs in the request structures need a valid ib_device.
+	 */
+	ret = nvme_rdma_dev_get(ctrl->device);
+	if (!ret) {
+		ret = -EINVAL;
+		goto out_free_tagset;
+	}
+
+	return set;
+
+out_free_tagset:
+	blk_mq_free_tag_set(set);
+out:
+	return ERR_PTR(ret);
+}
+
+static void nvme_rdma_destroy_admin_queue(struct nvme_rdma_ctrl *ctrl,
+		bool remove)
+{
+	if (remove) {
+		blk_cleanup_queue(ctrl->ctrl.admin_q);
+		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.admin_tagset);
+	}
+	if (ctrl->async_event_sqe.data) {
+		cancel_work_sync(&ctrl->ctrl.async_event_work);
+		nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe,
+				sizeof(struct nvme_command), DMA_TO_DEVICE);
+		ctrl->async_event_sqe.data = NULL;
+	}
+	nvme_rdma_free_queue(&ctrl->queues[0]);
+}
+
+static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl,
+		bool new)
+{
+	int error;
+
+	error = nvme_rdma_alloc_queue(ctrl, 0, NVME_AQ_DEPTH);
+	if (error)
+		return error;
+
+	ctrl->device = ctrl->queues[0].device;
+
+	ctrl->max_fr_pages = nvme_rdma_get_max_fr_pages(ctrl->device->dev);
+
+	error = nvme_rdma_alloc_qe(ctrl->device->dev, &ctrl->async_event_sqe,
+			sizeof(struct nvme_command), DMA_TO_DEVICE);
+	if (error)
+		goto out_free_queue;
+
+	if (new) {
+		ctrl->ctrl.admin_tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, true);
+		if (IS_ERR(ctrl->ctrl.admin_tagset)) {
+			error = PTR_ERR(ctrl->ctrl.admin_tagset);
+			goto out_free_async_qe;
+		}
+
+		ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
+		if (IS_ERR(ctrl->ctrl.admin_q)) {
+			error = PTR_ERR(ctrl->ctrl.admin_q);
+			goto out_free_tagset;
+		}
+	}
+
+	error = nvme_rdma_start_queue(ctrl, 0);
+	if (error)
+		goto out_cleanup_queue;
+
+	error = ctrl->ctrl.ops->reg_read64(&ctrl->ctrl, NVME_REG_CAP,
+			&ctrl->ctrl.cap);
+	if (error) {
+		dev_err(ctrl->ctrl.device,
+			"prop_get NVME_REG_CAP failed\n");
+		goto out_stop_queue;
+	}
+
+	ctrl->ctrl.sqsize =
+		min_t(int, NVME_CAP_MQES(ctrl->ctrl.cap), ctrl->ctrl.sqsize);
+
+	error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
+	if (error)
+		goto out_stop_queue;
+
+	ctrl->ctrl.max_hw_sectors =
+		(ctrl->max_fr_pages - 1) << (ilog2(SZ_4K) - 9);
+
+	error = nvme_init_identify(&ctrl->ctrl);
+	if (error)
+		goto out_stop_queue;
+
+	return 0;
+
+out_stop_queue:
+	nvme_rdma_stop_queue(&ctrl->queues[0]);
+out_cleanup_queue:
+	if (new)
+		blk_cleanup_queue(ctrl->ctrl.admin_q);
+out_free_tagset:
+	if (new)
+		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.admin_tagset);
+out_free_async_qe:
+	if (ctrl->async_event_sqe.data) {
+		nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe,
+			sizeof(struct nvme_command), DMA_TO_DEVICE);
+		ctrl->async_event_sqe.data = NULL;
+	}
+out_free_queue:
+	nvme_rdma_free_queue(&ctrl->queues[0]);
+	return error;
+}
+
+static void nvme_rdma_destroy_io_queues(struct nvme_rdma_ctrl *ctrl,
+		bool remove)
+{
+	if (remove) {
+		blk_cleanup_queue(ctrl->ctrl.connect_q);
+		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.tagset);
+	}
+	nvme_rdma_free_io_queues(ctrl);
+}
+
+static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new)
+{
+	int ret;
+
+	ret = nvme_rdma_alloc_io_queues(ctrl);
+	if (ret)
+		return ret;
+
+	if (new) {
+		ctrl->ctrl.tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, false);
+		if (IS_ERR(ctrl->ctrl.tagset)) {
+			ret = PTR_ERR(ctrl->ctrl.tagset);
+			goto out_free_io_queues;
+		}
+
+		ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
+		if (IS_ERR(ctrl->ctrl.connect_q)) {
+			ret = PTR_ERR(ctrl->ctrl.connect_q);
+			goto out_free_tag_set;
+		}
+	} else {
+		blk_mq_update_nr_hw_queues(&ctrl->tag_set,
+			ctrl->ctrl.queue_count - 1);
+	}
+
+	ret = nvme_rdma_start_io_queues(ctrl);
+	if (ret)
+		goto out_cleanup_connect_q;
+
+	return 0;
+
+out_cleanup_connect_q:
+	if (new)
+		blk_cleanup_queue(ctrl->ctrl.connect_q);
+out_free_tag_set:
+	if (new)
+		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.tagset);
+out_free_io_queues:
+	nvme_rdma_free_io_queues(ctrl);
+	return ret;
+}
+
+static void nvme_rdma_teardown_admin_queue(struct nvme_rdma_ctrl *ctrl,
+		bool remove)
+{
+	mutex_lock(&ctrl->teardown_lock);
+	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
+	nvme_rdma_stop_queue(&ctrl->queues[0]);
+	if (ctrl->ctrl.admin_tagset)
+		blk_mq_tagset_busy_iter(ctrl->ctrl.admin_tagset,
+			nvme_cancel_request, &ctrl->ctrl);
+	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
+	nvme_rdma_destroy_admin_queue(ctrl, remove);
+	mutex_unlock(&ctrl->teardown_lock);
+}
+
+static void nvme_rdma_teardown_io_queues(struct nvme_rdma_ctrl *ctrl,
+		bool remove)
+{
+	mutex_lock(&ctrl->teardown_lock);
+	if (ctrl->ctrl.queue_count > 1) {
+		nvme_stop_queues(&ctrl->ctrl);
+		nvme_rdma_stop_io_queues(ctrl);
+		if (ctrl->ctrl.tagset)
+			blk_mq_tagset_busy_iter(ctrl->ctrl.tagset,
+				nvme_cancel_request, &ctrl->ctrl);
+		if (remove)
+			nvme_start_queues(&ctrl->ctrl);
+		nvme_rdma_destroy_io_queues(ctrl, remove);
+	}
+	mutex_unlock(&ctrl->teardown_lock);
+}
+
+static void nvme_rdma_stop_ctrl(struct nvme_ctrl *nctrl)
+{
+	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
+
+	cancel_work_sync(&ctrl->err_work);
+	cancel_delayed_work_sync(&ctrl->reconnect_work);
+}
+
+static void nvme_rdma_free_ctrl(struct nvme_ctrl *nctrl)
+{
+	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
+
+	if (list_empty(&ctrl->list))
+		goto free_ctrl;
+
+	mutex_lock(&nvme_rdma_ctrl_mutex);
+	list_del(&ctrl->list);
+	mutex_unlock(&nvme_rdma_ctrl_mutex);
+
+	nvmf_free_options(nctrl->opts);
+free_ctrl:
+	kfree(ctrl->queues);
+	kfree(ctrl);
+}
+
+static void nvme_rdma_reconnect_or_remove(struct nvme_rdma_ctrl *ctrl)
+{
+	/* If we are resetting/deleting then do nothing */
+	if (ctrl->ctrl.state != NVME_CTRL_CONNECTING) {
+		WARN_ON_ONCE(ctrl->ctrl.state == NVME_CTRL_NEW ||
+			ctrl->ctrl.state == NVME_CTRL_LIVE);
+		return;
+	}
+
+	if (nvmf_should_reconnect(&ctrl->ctrl)) {
+		dev_info(ctrl->ctrl.device, "Reconnecting in %d seconds...\n",
+			ctrl->ctrl.opts->reconnect_delay);
+		queue_delayed_work(nvme_wq, &ctrl->reconnect_work,
+				ctrl->ctrl.opts->reconnect_delay * HZ);
+	} else {
+		nvme_delete_ctrl(&ctrl->ctrl);
+	}
+}
+
+static int nvme_rdma_setup_ctrl(struct nvme_rdma_ctrl *ctrl, bool new)
+{
+	int ret = -EINVAL;
+	bool changed;
+
+	ret = nvme_rdma_configure_admin_queue(ctrl, new);
+	if (ret)
+		return ret;
+
+	if (ctrl->ctrl.icdoff) {
+		ret = -EOPNOTSUPP;
+		dev_err(ctrl->ctrl.device, "icdoff is not supported!\n");
+		goto destroy_admin;
+	}
+
+	if (!(ctrl->ctrl.sgls & (1 << 2))) {
+		ret = -EOPNOTSUPP;
+		dev_err(ctrl->ctrl.device,
+			"Mandatory keyed sgls are not supported!\n");
+		goto destroy_admin;
+	}
+
+	if (ctrl->ctrl.opts->queue_size > ctrl->ctrl.sqsize + 1) {
+		dev_warn(ctrl->ctrl.device,
+			"queue_size %zu > ctrl sqsize %u, clamping down\n",
+			ctrl->ctrl.opts->queue_size, ctrl->ctrl.sqsize + 1);
+	}
+
+	if (ctrl->ctrl.sqsize + 1 > ctrl->ctrl.maxcmd) {
+		dev_warn(ctrl->ctrl.device,
+			"sqsize %u > ctrl maxcmd %u, clamping down\n",
+			ctrl->ctrl.sqsize + 1, ctrl->ctrl.maxcmd);
+		ctrl->ctrl.sqsize = ctrl->ctrl.maxcmd - 1;
+	}
+
+	if (ctrl->ctrl.sgls & (1 << 20))
+		ctrl->use_inline_data = true;
+
+	if (ctrl->ctrl.queue_count > 1) {
+		ret = nvme_rdma_configure_io_queues(ctrl, new);
+		if (ret)
+			goto destroy_admin;
+	}
+
+	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
+	if (!changed) {
+		/* state change failure is ok if we're in DELETING state */
+		WARN_ON_ONCE(ctrl->ctrl.state != NVME_CTRL_DELETING);
+		ret = -EINVAL;
+		goto destroy_io;
+	}
+
+	nvme_start_ctrl(&ctrl->ctrl);
+	return 0;
+
+destroy_io:
+	if (ctrl->ctrl.queue_count > 1)
+		nvme_rdma_destroy_io_queues(ctrl, new);
+destroy_admin:
+	nvme_rdma_stop_queue(&ctrl->queues[0]);
+	nvme_rdma_destroy_admin_queue(ctrl, new);
+	return ret;
+}
+
+static void nvme_rdma_reconnect_ctrl_work(struct work_struct *work)
+{
+	struct nvme_rdma_ctrl *ctrl = container_of(to_delayed_work(work),
+			struct nvme_rdma_ctrl, reconnect_work);
+
+	++ctrl->ctrl.nr_reconnects;
+
+	if (nvme_rdma_setup_ctrl(ctrl, false))
+		goto requeue;
+
+	dev_info(ctrl->ctrl.device, "Successfully reconnected (%d attempts)\n",
+			ctrl->ctrl.nr_reconnects);
+
+	ctrl->ctrl.nr_reconnects = 0;
+
+	return;
+
+requeue:
+	dev_info(ctrl->ctrl.device, "Failed reconnect attempt %d\n",
+			ctrl->ctrl.nr_reconnects);
+	nvme_rdma_reconnect_or_remove(ctrl);
+}
+
+static void nvme_rdma_error_recovery_work(struct work_struct *work)
+{
+	struct nvme_rdma_ctrl *ctrl = container_of(work,
+			struct nvme_rdma_ctrl, err_work);
+
+	nvme_stop_keep_alive(&ctrl->ctrl);
+	flush_work(&ctrl->ctrl.async_event_work);
+	nvme_rdma_teardown_io_queues(ctrl, false);
+	nvme_start_queues(&ctrl->ctrl);
+	nvme_rdma_teardown_admin_queue(ctrl, false);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
+		/* state change failure is ok if we're in DELETING state */
+		WARN_ON_ONCE(ctrl->ctrl.state != NVME_CTRL_DELETING);
+		return;
+	}
+
+	nvme_rdma_reconnect_or_remove(ctrl);
+}
+
+static void nvme_rdma_error_recovery(struct nvme_rdma_ctrl *ctrl)
+{
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING))
+		return;
+
+	queue_work(nvme_wq, &ctrl->err_work);
+}
+
+static void nvme_rdma_wr_error(struct ib_cq *cq, struct ib_wc *wc,
+		const char *op)
+{
+	struct nvme_rdma_queue *queue = cq->cq_context;
+	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
+
+	if (ctrl->ctrl.state == NVME_CTRL_LIVE)
+		dev_info(ctrl->ctrl.device,
+			     "%s for CQE 0x%p failed with status %s (%d)\n",
+			     op, wc->wr_cqe,
+			     ib_wc_status_msg(wc->status), wc->status);
+	nvme_rdma_error_recovery(ctrl);
+}
+
+static void nvme_rdma_memreg_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	if (unlikely(wc->status != IB_WC_SUCCESS))
+		nvme_rdma_wr_error(cq, wc, "MEMREG");
+}
+
+static void nvme_rdma_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	struct nvme_rdma_request *req =
+		container_of(wc->wr_cqe, struct nvme_rdma_request, reg_cqe);
+	struct request *rq = blk_mq_rq_from_pdu(req);
+
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
+		nvme_rdma_wr_error(cq, wc, "LOCAL_INV");
+		return;
+	}
+
+	if (refcount_dec_and_test(&req->ref))
+		nvme_end_request(rq, req->status, req->result);
+
+}
+
+static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_request *req)
+{
+	struct ib_send_wr wr = {
+		.opcode		    = IB_WR_LOCAL_INV,
+		.next		    = NULL,
+		.num_sge	    = 0,
+		.send_flags	    = IB_SEND_SIGNALED,
+		.ex.invalidate_rkey = req->mr->rkey,
+	};
+
+	req->reg_cqe.done = nvme_rdma_inv_rkey_done;
+	wr.wr_cqe = &req->reg_cqe;
+
+	return ib_post_send(queue->qp, &wr, NULL);
+}
+
+static void nvme_rdma_unmap_data(struct nvme_rdma_queue *queue,
+		struct request *rq)
+{
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	struct nvme_rdma_device *dev = queue->device;
+	struct ib_device *ibdev = dev->dev;
+
+	if (!blk_rq_payload_bytes(rq))
+		return;
+
+	if (req->mr) {
+		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
+		req->mr = NULL;
+	}
+
+	ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
+			req->nents, rq_data_dir(rq) ==
+				    WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+
+	nvme_cleanup_cmd(rq);
+	sg_free_table_chained(&req->sg_table, true);
+}
+
+static int nvme_rdma_set_sg_null(struct nvme_command *c)
+{
+	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
+
+	sg->addr = 0;
+	put_unaligned_le24(0, sg->length);
+	put_unaligned_le32(0, sg->key);
+	sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
+	return 0;
+}
+
+static int nvme_rdma_map_sg_inline(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_request *req, struct nvme_command *c,
+		int count)
+{
+	struct nvme_sgl_desc *sg = &c->common.dptr.sgl;
+	struct scatterlist *sgl = req->sg_table.sgl;
+	struct ib_sge *sge = &req->sge[1];
+	u32 len = 0;
+	int i;
+
+	for (i = 0; i < count; i++, sgl++, sge++) {
+		sge->addr = sg_dma_address(sgl);
+		sge->length = sg_dma_len(sgl);
+		sge->lkey = queue->device->pd->local_dma_lkey;
+		len += sge->length;
+	}
+
+	sg->addr = cpu_to_le64(queue->ctrl->ctrl.icdoff);
+	sg->length = cpu_to_le32(len);
+	sg->type = (NVME_SGL_FMT_DATA_DESC << 4) | NVME_SGL_FMT_OFFSET;
+
+	req->num_sge += count;
+	return 0;
+}
+
+static int nvme_rdma_map_sg_single(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_request *req, struct nvme_command *c)
+{
+	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
+
+	sg->addr = cpu_to_le64(sg_dma_address(req->sg_table.sgl));
+	put_unaligned_le24(sg_dma_len(req->sg_table.sgl), sg->length);
+	put_unaligned_le32(queue->device->pd->unsafe_global_rkey, sg->key);
+	sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
+	return 0;
+}
+
+static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_request *req, struct nvme_command *c,
+		int count)
+{
+	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
+	int nr;
+
+	req->mr = ib_mr_pool_get(queue->qp, &queue->qp->rdma_mrs);
+	if (WARN_ON_ONCE(!req->mr))
+		return -EAGAIN;
+
+	/*
+	 * Align the MR to a 4K page size to match the ctrl page size and
+	 * the block virtual boundary.
+	 */
+	nr = ib_map_mr_sg(req->mr, req->sg_table.sgl, count, NULL, SZ_4K);
+	if (unlikely(nr < count)) {
+		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
+		req->mr = NULL;
+		if (nr < 0)
+			return nr;
+		return -EINVAL;
+	}
+
+	ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey));
+
+	req->reg_cqe.done = nvme_rdma_memreg_done;
+	memset(&req->reg_wr, 0, sizeof(req->reg_wr));
+	req->reg_wr.wr.opcode = IB_WR_REG_MR;
+	req->reg_wr.wr.wr_cqe = &req->reg_cqe;
+	req->reg_wr.wr.num_sge = 0;
+	req->reg_wr.mr = req->mr;
+	req->reg_wr.key = req->mr->rkey;
+	req->reg_wr.access = IB_ACCESS_LOCAL_WRITE |
+			     IB_ACCESS_REMOTE_READ |
+			     IB_ACCESS_REMOTE_WRITE;
+
+	sg->addr = cpu_to_le64(req->mr->iova);
+	put_unaligned_le24(req->mr->length, sg->length);
+	put_unaligned_le32(req->mr->rkey, sg->key);
+	sg->type = (NVME_KEY_SGL_FMT_DATA_DESC << 4) |
+			NVME_SGL_FMT_INVALIDATE;
+
+	return 0;
+}
+
+static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
+		struct request *rq, struct nvme_command *c)
+{
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	struct nvme_rdma_device *dev = queue->device;
+	struct ib_device *ibdev = dev->dev;
+	int count, ret;
+
+	req->num_sge = 1;
+	refcount_set(&req->ref, 2); /* send and recv completions */
+
+	c->common.flags |= NVME_CMD_SGL_METABUF;
+
+	if (!blk_rq_payload_bytes(rq))
+		return nvme_rdma_set_sg_null(c);
+
+	req->sg_table.sgl = req->first_sgl;
+	ret = sg_alloc_table_chained(&req->sg_table,
+			blk_rq_nr_phys_segments(rq), req->sg_table.sgl);
+	if (ret)
+		return -ENOMEM;
+
+	req->nents = blk_rq_map_sg(rq->q, rq, req->sg_table.sgl);
+
+	count = ib_dma_map_sg(ibdev, req->sg_table.sgl, req->nents,
+		    rq_data_dir(rq) == WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+	if (unlikely(count <= 0)) {
+		ret = -EIO;
+		goto out_free_table;
+	}
+
+	if (count <= dev->num_inline_segments) {
+		if (rq_data_dir(rq) == WRITE && nvme_rdma_queue_idx(queue) &&
+		    queue->ctrl->use_inline_data &&
+		    blk_rq_payload_bytes(rq) <=
+				nvme_rdma_inline_data_size(queue)) {
+			ret = nvme_rdma_map_sg_inline(queue, req, c, count);
+			goto out;
+		}
+
+		if (count == 1 && dev->pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY) {
+			ret = nvme_rdma_map_sg_single(queue, req, c);
+			goto out;
+		}
+	}
+
+	ret = nvme_rdma_map_sg_fr(queue, req, c, count);
+out:
+	if (unlikely(ret))
+		goto out_unmap_sg;
+
+	return 0;
+
+out_unmap_sg:
+	ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
+			req->nents, rq_data_dir(rq) ==
+			WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+out_free_table:
+	sg_free_table_chained(&req->sg_table, true);
+	return ret;
+}
+
+static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	struct nvme_rdma_qe *qe =
+		container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
+	struct nvme_rdma_request *req =
+		container_of(qe, struct nvme_rdma_request, sqe);
+	struct request *rq = blk_mq_rq_from_pdu(req);
+
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
+		nvme_rdma_wr_error(cq, wc, "SEND");
+		return;
+	}
+
+	if (refcount_dec_and_test(&req->ref))
+		nvme_end_request(rq, req->status, req->result);
+}
+
+static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_qe *qe, struct ib_sge *sge, u32 num_sge,
+		struct ib_send_wr *first)
+{
+	struct ib_send_wr wr;
+	int ret;
+
+	sge->addr   = qe->dma;
+	sge->length = sizeof(struct nvme_command),
+	sge->lkey   = queue->device->pd->local_dma_lkey;
+
+	wr.next       = NULL;
+	wr.wr_cqe     = &qe->cqe;
+	wr.sg_list    = sge;
+	wr.num_sge    = num_sge;
+	wr.opcode     = IB_WR_SEND;
+	wr.send_flags = IB_SEND_SIGNALED;
+
+	if (first)
+		first->next = &wr;
+	else
+		first = &wr;
+
+	ret = ib_post_send(queue->qp, first, NULL);
+	if (unlikely(ret)) {
+		dev_err(queue->ctrl->ctrl.device,
+			     "%s failed with error code %d\n", __func__, ret);
+	}
+	return ret;
+}
+
+static int nvme_rdma_post_recv(struct nvme_rdma_queue *queue,
+		struct nvme_rdma_qe *qe)
+{
+	struct ib_recv_wr wr;
+	struct ib_sge list;
+	int ret;
+
+	list.addr   = qe->dma;
+	list.length = sizeof(struct nvme_completion);
+	list.lkey   = queue->device->pd->local_dma_lkey;
+
+	qe->cqe.done = nvme_rdma_recv_done;
+
+	wr.next     = NULL;
+	wr.wr_cqe   = &qe->cqe;
+	wr.sg_list  = &list;
+	wr.num_sge  = 1;
+
+	ret = ib_post_recv(queue->qp, &wr, NULL);
+	if (unlikely(ret)) {
+		dev_err(queue->ctrl->ctrl.device,
+			"%s failed with error code %d\n", __func__, ret);
+	}
+	return ret;
+}
+
+static struct blk_mq_tags *nvme_rdma_tagset(struct nvme_rdma_queue *queue)
+{
+	u32 queue_idx = nvme_rdma_queue_idx(queue);
+
+	if (queue_idx == 0)
+		return queue->ctrl->admin_tag_set.tags[queue_idx];
+	return queue->ctrl->tag_set.tags[queue_idx - 1];
+}
+
+static void nvme_rdma_async_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	if (unlikely(wc->status != IB_WC_SUCCESS))
+		nvme_rdma_wr_error(cq, wc, "ASYNC");
+}
+
+static void nvme_rdma_submit_async_event(struct nvme_ctrl *arg)
+{
+	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(arg);
+	struct nvme_rdma_queue *queue = &ctrl->queues[0];
+	struct ib_device *dev = queue->device->dev;
+	struct nvme_rdma_qe *sqe = &ctrl->async_event_sqe;
+	struct nvme_command *cmd = sqe->data;
+	struct ib_sge sge;
+	int ret;
+
+	ib_dma_sync_single_for_cpu(dev, sqe->dma, sizeof(*cmd), DMA_TO_DEVICE);
+
+	memset(cmd, 0, sizeof(*cmd));
+	cmd->common.opcode = nvme_admin_async_event;
+	cmd->common.command_id = NVME_AQ_BLK_MQ_DEPTH;
+	cmd->common.flags |= NVME_CMD_SGL_METABUF;
+	nvme_rdma_set_sg_null(cmd);
+
+	sqe->cqe.done = nvme_rdma_async_done;
+
+	ib_dma_sync_single_for_device(dev, sqe->dma, sizeof(*cmd),
+			DMA_TO_DEVICE);
+
+	ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL);
+	WARN_ON_ONCE(ret);
+}
+
+static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue,
+		struct nvme_completion *cqe, struct ib_wc *wc, int tag)
+{
+	struct request *rq;
+	struct nvme_rdma_request *req;
+	int ret = 0;
+
+	rq = blk_mq_tag_to_rq(nvme_rdma_tagset(queue), cqe->command_id);
+	if (!rq) {
+		dev_err(queue->ctrl->ctrl.device,
+			"tag 0x%x on QP %#x not found\n",
+			cqe->command_id, queue->qp->qp_num);
+		nvme_rdma_error_recovery(queue->ctrl);
+		return ret;
+	}
+	req = blk_mq_rq_to_pdu(rq);
+
+	req->status = cqe->status;
+	req->result = cqe->result;
+
+	if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
+		if (unlikely(wc->ex.invalidate_rkey != req->mr->rkey)) {
+			dev_err(queue->ctrl->ctrl.device,
+				"Bogus remote invalidation for rkey %#x\n",
+				req->mr->rkey);
+			nvme_rdma_error_recovery(queue->ctrl);
+		}
+	} else if (req->mr) {
+		ret = nvme_rdma_inv_rkey(queue, req);
+		if (unlikely(ret < 0)) {
+			dev_err(queue->ctrl->ctrl.device,
+				"Queueing INV WR for rkey %#x failed (%d)\n",
+				req->mr->rkey, ret);
+			nvme_rdma_error_recovery(queue->ctrl);
+		}
+		/* the local invalidation completion will end the request */
+		return 0;
+	}
+
+	if (refcount_dec_and_test(&req->ref)) {
+		if (rq->tag == tag)
+			ret = 1;
+		nvme_end_request(rq, req->status, req->result);
+	}
+
+	return ret;
+}
+
+static int __nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc, int tag)
+{
+	struct nvme_rdma_qe *qe =
+		container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
+	struct nvme_rdma_queue *queue = cq->cq_context;
+	struct ib_device *ibdev = queue->device->dev;
+	struct nvme_completion *cqe = qe->data;
+	const size_t len = sizeof(struct nvme_completion);
+	int ret = 0;
+
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
+		nvme_rdma_wr_error(cq, wc, "RECV");
+		return 0;
+	}
+
+	ib_dma_sync_single_for_cpu(ibdev, qe->dma, len, DMA_FROM_DEVICE);
+	/*
+	 * AEN requests are special as they don't time out and can
+	 * survive any kind of queue freeze and often don't respond to
+	 * aborts.  We don't even bother to allocate a struct request
+	 * for them but rather special case them here.
+	 */
+	if (unlikely(nvme_rdma_queue_idx(queue) == 0 &&
+			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH))
+		nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
+				&cqe->result);
+	else
+		ret = nvme_rdma_process_nvme_rsp(queue, cqe, wc, tag);
+	ib_dma_sync_single_for_device(ibdev, qe->dma, len, DMA_FROM_DEVICE);
+
+	nvme_rdma_post_recv(queue, qe);
+	return ret;
+}
+
+static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	__nvme_rdma_recv_done(cq, wc, -1);
+}
+
+static int nvme_rdma_conn_established(struct nvme_rdma_queue *queue)
+{
+	int ret, i;
+
+	for (i = 0; i < queue->queue_size; i++) {
+		ret = nvme_rdma_post_recv(queue, &queue->rsp_ring[i]);
+		if (ret)
+			goto out_destroy_queue_ib;
+	}
+
+	return 0;
+
+out_destroy_queue_ib:
+	nvme_rdma_destroy_queue_ib(queue);
+	return ret;
+}
+
+static int nvme_rdma_conn_rejected(struct nvme_rdma_queue *queue,
+		struct rdma_cm_event *ev)
+{
+	struct rdma_cm_id *cm_id = queue->cm_id;
+	int status = ev->status;
+	const char *rej_msg;
+	const struct nvme_rdma_cm_rej *rej_data;
+	u8 rej_data_len;
+
+	rej_msg = rdma_reject_msg(cm_id, status);
+	rej_data = rdma_consumer_reject_data(cm_id, ev, &rej_data_len);
+
+	if (rej_data && rej_data_len >= sizeof(u16)) {
+		u16 sts = le16_to_cpu(rej_data->sts);
+
+		dev_err(queue->ctrl->ctrl.device,
+		      "Connect rejected: status %d (%s) nvme status %d (%s).\n",
+		      status, rej_msg, sts, nvme_rdma_cm_msg(sts));
+	} else {
+		dev_err(queue->ctrl->ctrl.device,
+			"Connect rejected: status %d (%s).\n", status, rej_msg);
+	}
+
+	return -ECONNRESET;
+}
+
+static int nvme_rdma_addr_resolved(struct nvme_rdma_queue *queue)
+{
+	int ret;
+
+	ret = nvme_rdma_create_queue_ib(queue);
+	if (ret)
+		return ret;
+
+	ret = rdma_resolve_route(queue->cm_id, NVME_RDMA_CONNECT_TIMEOUT_MS);
+	if (ret) {
+		dev_err(queue->ctrl->ctrl.device,
+			"rdma_resolve_route failed (%d).\n",
+			queue->cm_error);
+		goto out_destroy_queue;
+	}
+
+	return 0;
+
+out_destroy_queue:
+	nvme_rdma_destroy_queue_ib(queue);
+	return ret;
+}
+
+static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
+{
+	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
+	struct rdma_conn_param param = { };
+	struct nvme_rdma_cm_req priv = { };
+	int ret;
+
+	param.qp_num = queue->qp->qp_num;
+	param.flow_control = 1;
+
+	param.responder_resources = queue->device->dev->attrs.max_qp_rd_atom;
+	/* maximum retry count */
+	param.retry_count = 7;
+	param.rnr_retry_count = 7;
+	param.private_data = &priv;
+	param.private_data_len = sizeof(priv);
+
+	priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
+	priv.qid = cpu_to_le16(nvme_rdma_queue_idx(queue));
+	/*
+	 * set the admin queue depth to the minimum size
+	 * specified by the Fabrics standard.
+	 */
+	if (priv.qid == 0) {
+		priv.hrqsize = cpu_to_le16(NVME_AQ_DEPTH);
+		priv.hsqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
+	} else {
+		/*
+		 * current interpretation of the fabrics spec
+		 * is at minimum you make hrqsize sqsize+1, or a
+		 * 1's based representation of sqsize.
+		 */
+		priv.hrqsize = cpu_to_le16(queue->queue_size);
+		priv.hsqsize = cpu_to_le16(queue->ctrl->ctrl.sqsize);
+	}
+
+	ret = rdma_connect(queue->cm_id, &param);
+	if (ret) {
+		dev_err(ctrl->ctrl.device,
+			"rdma_connect failed (%d).\n", ret);
+		goto out_destroy_queue_ib;
+	}
+
+	return 0;
+
+out_destroy_queue_ib:
+	nvme_rdma_destroy_queue_ib(queue);
+	return ret;
+}
+
+static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
+		struct rdma_cm_event *ev)
+{
+	struct nvme_rdma_queue *queue = cm_id->context;
+	int cm_error = 0;
+
+	dev_dbg(queue->ctrl->ctrl.device, "%s (%d): status %d id %p\n",
+		rdma_event_msg(ev->event), ev->event,
+		ev->status, cm_id);
+
+	switch (ev->event) {
+	case RDMA_CM_EVENT_ADDR_RESOLVED:
+		cm_error = nvme_rdma_addr_resolved(queue);
+		break;
+	case RDMA_CM_EVENT_ROUTE_RESOLVED:
+		cm_error = nvme_rdma_route_resolved(queue);
+		break;
+	case RDMA_CM_EVENT_ESTABLISHED:
+		queue->cm_error = nvme_rdma_conn_established(queue);
+		/* complete cm_done regardless of success/failure */
+		complete(&queue->cm_done);
+		return 0;
+	case RDMA_CM_EVENT_REJECTED:
+		cm_error = nvme_rdma_conn_rejected(queue, ev);
+		break;
+	case RDMA_CM_EVENT_ROUTE_ERROR:
+	case RDMA_CM_EVENT_CONNECT_ERROR:
+	case RDMA_CM_EVENT_UNREACHABLE:
+		nvme_rdma_destroy_queue_ib(queue);
+		/* fall through */
+	case RDMA_CM_EVENT_ADDR_ERROR:
+		dev_dbg(queue->ctrl->ctrl.device,
+			"CM error event %d\n", ev->event);
+		cm_error = -ECONNRESET;
+		break;
+	case RDMA_CM_EVENT_DISCONNECTED:
+	case RDMA_CM_EVENT_ADDR_CHANGE:
+	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
+		dev_dbg(queue->ctrl->ctrl.device,
+			"disconnect received - connection closed\n");
+		nvme_rdma_error_recovery(queue->ctrl);
+		break;
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+		/* device removal is handled via the ib_client API */
+		break;
+	default:
+		dev_err(queue->ctrl->ctrl.device,
+			"Unexpected RDMA CM event (%d)\n", ev->event);
+		nvme_rdma_error_recovery(queue->ctrl);
+		break;
+	}
+
+	if (cm_error) {
+		queue->cm_error = cm_error;
+		complete(&queue->cm_done);
+	}
+
+	return 0;
+}
+
+static enum blk_eh_timer_return
+nvme_rdma_timeout(struct request *rq, bool reserved)
+{
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	struct nvme_rdma_queue *queue = req->queue;
+	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
+
+	dev_warn(ctrl->ctrl.device, "I/O %d QID %d timeout\n",
+		 rq->tag, nvme_rdma_queue_idx(queue));
+
+	if (ctrl->ctrl.state != NVME_CTRL_LIVE) {
+		/*
+		 * Teardown immediately if controller times out while starting
+		 * or we are already started error recovery. all outstanding
+		 * requests are completed on shutdown, so we return BLK_EH_DONE.
+		 */
+		flush_work(&ctrl->err_work);
+		nvme_rdma_teardown_io_queues(ctrl, false);
+		nvme_rdma_teardown_admin_queue(ctrl, false);
+		return BLK_EH_DONE;
+	}
+
+	dev_warn(ctrl->ctrl.device, "starting error recovery\n");
+	nvme_rdma_error_recovery(ctrl);
+
+	return BLK_EH_RESET_TIMER;
+}
+
+static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
+		const struct blk_mq_queue_data *bd)
+{
+	struct nvme_ns *ns = hctx->queue->queuedata;
+	struct nvme_rdma_queue *queue = hctx->driver_data;
+	struct request *rq = bd->rq;
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+	struct nvme_rdma_qe *sqe = &req->sqe;
+	struct nvme_command *c = sqe->data;
+	struct ib_device *dev;
+	bool queue_ready = test_bit(NVME_RDMA_Q_LIVE, &queue->flags);
+	blk_status_t ret;
+	int err;
+
+	WARN_ON_ONCE(rq->tag < 0);
+
+	if (!nvmf_check_ready(&queue->ctrl->ctrl, rq, queue_ready))
+		return nvmf_fail_nonready_command(&queue->ctrl->ctrl, rq);
+
+	dev = queue->device->dev;
+	ib_dma_sync_single_for_cpu(dev, sqe->dma,
+			sizeof(struct nvme_command), DMA_TO_DEVICE);
+
+	ret = nvme_setup_cmd(ns, rq, c);
+	if (ret)
+		return ret;
+
+	blk_mq_start_request(rq);
+
+	err = nvme_rdma_map_data(queue, rq, c);
+	if (unlikely(err < 0)) {
+		dev_err(queue->ctrl->ctrl.device,
+			     "Failed to map data (%d)\n", err);
+		nvme_cleanup_cmd(rq);
+		goto err;
+	}
+
+	sqe->cqe.done = nvme_rdma_send_done;
+
+	ib_dma_sync_single_for_device(dev, sqe->dma,
+			sizeof(struct nvme_command), DMA_TO_DEVICE);
+
+	err = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
+			req->mr ? &req->reg_wr.wr : NULL);
+	if (unlikely(err)) {
+		nvme_rdma_unmap_data(queue, rq);
+		goto err;
+	}
+
+	return BLK_STS_OK;
+err:
+	if (err == -ENOMEM || err == -EAGAIN)
+		return BLK_STS_RESOURCE;
+	return BLK_STS_IOERR;
+}
+
+static int nvme_rdma_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
+{
+	struct nvme_rdma_queue *queue = hctx->driver_data;
+	struct ib_cq *cq = queue->ib_cq;
+	struct ib_wc wc;
+	int found = 0;
+
+	while (ib_poll_cq(cq, 1, &wc) > 0) {
+		struct ib_cqe *cqe = wc.wr_cqe;
+
+		if (cqe) {
+			if (cqe->done == nvme_rdma_recv_done)
+				found |= __nvme_rdma_recv_done(cq, &wc, tag);
+			else
+				cqe->done(cq, &wc);
+		}
+	}
+
+	return found;
+}
+
+static void nvme_rdma_complete_rq(struct request *rq)
+{
+	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
+
+	nvme_rdma_unmap_data(req->queue, rq);
+	nvme_complete_rq(rq);
+}
+
+static int nvme_rdma_map_queues(struct blk_mq_tag_set *set)
+{
+	struct nvme_rdma_ctrl *ctrl = set->driver_data;
+
+	return blk_mq_rdma_map_queues(set, ctrl->device->dev, 0);
+}
+
+static const struct blk_mq_ops nvme_rdma_mq_ops = {
+	.queue_rq	= nvme_rdma_queue_rq,
+	.complete	= nvme_rdma_complete_rq,
+	.init_request	= nvme_rdma_init_request,
+	.exit_request	= nvme_rdma_exit_request,
+	.init_hctx	= nvme_rdma_init_hctx,
+	.poll		= nvme_rdma_poll,
+	.timeout	= nvme_rdma_timeout,
+	.map_queues	= nvme_rdma_map_queues,
+};
+
+static const struct blk_mq_ops nvme_rdma_admin_mq_ops = {
+	.queue_rq	= nvme_rdma_queue_rq,
+	.complete	= nvme_rdma_complete_rq,
+	.init_request	= nvme_rdma_init_request,
+	.exit_request	= nvme_rdma_exit_request,
+	.init_hctx	= nvme_rdma_init_admin_hctx,
+	.timeout	= nvme_rdma_timeout,
+};
+
+static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl, bool shutdown)
+{
+	nvme_rdma_teardown_io_queues(ctrl, shutdown);
+	if (shutdown)
+		nvme_shutdown_ctrl(&ctrl->ctrl);
+	else
+		nvme_disable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
+	nvme_rdma_teardown_admin_queue(ctrl, shutdown);
+}
+
+static void nvme_rdma_delete_ctrl(struct nvme_ctrl *ctrl)
+{
+	nvme_rdma_shutdown_ctrl(to_rdma_ctrl(ctrl), true);
+}
+
+static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
+{
+	struct nvme_rdma_ctrl *ctrl =
+		container_of(work, struct nvme_rdma_ctrl, ctrl.reset_work);
+
+	nvme_stop_ctrl(&ctrl->ctrl);
+	nvme_rdma_shutdown_ctrl(ctrl, false);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
+		/* state change failure should never happen */
+		WARN_ON_ONCE(1);
+		return;
+	}
+
+	if (nvme_rdma_setup_ctrl(ctrl, false))
+		goto out_fail;
+
+	return;
+
+out_fail:
+	++ctrl->ctrl.nr_reconnects;
+	nvme_rdma_reconnect_or_remove(ctrl);
+}
+
+static const struct nvme_ctrl_ops nvme_rdma_ctrl_ops = {
+	.name			= "rdma",
+	.module			= THIS_MODULE,
+	.flags			= NVME_F_FABRICS,
+	.reg_read32		= nvmf_reg_read32,
+	.reg_read64		= nvmf_reg_read64,
+	.reg_write32		= nvmf_reg_write32,
+	.free_ctrl		= nvme_rdma_free_ctrl,
+	.submit_async_event	= nvme_rdma_submit_async_event,
+	.delete_ctrl		= nvme_rdma_delete_ctrl,
+	.get_address		= nvmf_get_address,
+	.stop_ctrl		= nvme_rdma_stop_ctrl,
+};
+
+static inline bool
+__nvme_rdma_options_match(struct nvme_rdma_ctrl *ctrl,
+	struct nvmf_ctrl_options *opts)
+{
+	char *stdport = __stringify(NVME_RDMA_IP_PORT);
+
+
+	if (!nvmf_ctlr_matches_baseopts(&ctrl->ctrl, opts) ||
+	    strcmp(opts->traddr, ctrl->ctrl.opts->traddr))
+		return false;
+
+	if (opts->mask & NVMF_OPT_TRSVCID &&
+	    ctrl->ctrl.opts->mask & NVMF_OPT_TRSVCID) {
+		if (strcmp(opts->trsvcid, ctrl->ctrl.opts->trsvcid))
+			return false;
+	} else if (opts->mask & NVMF_OPT_TRSVCID) {
+		if (strcmp(opts->trsvcid, stdport))
+			return false;
+	} else if (ctrl->ctrl.opts->mask & NVMF_OPT_TRSVCID) {
+		if (strcmp(stdport, ctrl->ctrl.opts->trsvcid))
+			return false;
+	}
+	/* else, it's a match as both have stdport. Fall to next checks */
+
+	/*
+	 * checking the local address is rough. In most cases, one
+	 * is not specified and the host port is selected by the stack.
+	 *
+	 * Assume no match if:
+	 *  local address is specified and address is not the same
+	 *  local address is not specified but remote is, or vice versa
+	 *    (admin using specific host_traddr when it matters).
+	 */
+	if (opts->mask & NVMF_OPT_HOST_TRADDR &&
+	    ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR) {
+		if (strcmp(opts->host_traddr, ctrl->ctrl.opts->host_traddr))
+			return false;
+	} else if (opts->mask & NVMF_OPT_HOST_TRADDR ||
+		   ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR)
+		return false;
+	/*
+	 * if neither controller had an host port specified, assume it's
+	 * a match as everything else matched.
+	 */
+
+	return true;
+}
+
+/*
+ * Fails a connection request if it matches an existing controller
+ * (association) with the same tuple:
+ * <Host NQN, Host ID, local address, remote address, remote port, SUBSYS NQN>
+ *
+ * if local address is not specified in the request, it will match an
+ * existing controller with all the other parameters the same and no
+ * local port address specified as well.
+ *
+ * The ports don't need to be compared as they are intrinsically
+ * already matched by the port pointers supplied.
+ */
+static bool
+nvme_rdma_existing_controller(struct nvmf_ctrl_options *opts)
+{
+	struct nvme_rdma_ctrl *ctrl;
+	bool found = false;
+
+	mutex_lock(&nvme_rdma_ctrl_mutex);
+	list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
+		found = __nvme_rdma_options_match(ctrl, opts);
+		if (found)
+			break;
+	}
+	mutex_unlock(&nvme_rdma_ctrl_mutex);
+
+	return found;
+}
+
+static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
+		struct nvmf_ctrl_options *opts)
+{
+	struct nvme_rdma_ctrl *ctrl;
+	int ret;
+	bool changed;
+	char *port;
+
+	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
+	if (!ctrl)
+		return ERR_PTR(-ENOMEM);
+	ctrl->ctrl.opts = opts;
+	INIT_LIST_HEAD(&ctrl->list);
+	mutex_init(&ctrl->teardown_lock);
+
+	if (opts->mask & NVMF_OPT_TRSVCID)
+		port = opts->trsvcid;
+	else
+		port = __stringify(NVME_RDMA_IP_PORT);
+
+	ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
+			opts->traddr, port, &ctrl->addr);
+	if (ret) {
+		pr_err("malformed address passed: %s:%s\n", opts->traddr, port);
+		goto out_free_ctrl;
+	}
+
+	if (opts->mask & NVMF_OPT_HOST_TRADDR) {
+		ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
+			opts->host_traddr, NULL, &ctrl->src_addr);
+		if (ret) {
+			pr_err("malformed src address passed: %s\n",
+			       opts->host_traddr);
+			goto out_free_ctrl;
+		}
+	}
+
+	if (!opts->duplicate_connect && nvme_rdma_existing_controller(opts)) {
+		ret = -EALREADY;
+		goto out_free_ctrl;
+	}
+
+	INIT_DELAYED_WORK(&ctrl->reconnect_work,
+			nvme_rdma_reconnect_ctrl_work);
+	INIT_WORK(&ctrl->err_work, nvme_rdma_error_recovery_work);
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_rdma_reset_ctrl_work);
+
+	ctrl->ctrl.queue_count = opts->nr_io_queues + 1; /* +1 for admin queue */
+	ctrl->ctrl.sqsize = opts->queue_size - 1;
+	ctrl->ctrl.kato = opts->kato;
+
+	ret = -ENOMEM;
+	ctrl->queues = kcalloc(ctrl->ctrl.queue_count, sizeof(*ctrl->queues),
+				GFP_KERNEL);
+	if (!ctrl->queues)
+		goto out_free_ctrl;
+
+	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_rdma_ctrl_ops,
+				0 /* no quirks, we're perfect! */);
+	if (ret)
+		goto out_kfree_queues;
+
+	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING);
+	WARN_ON_ONCE(!changed);
+
+	ret = nvme_rdma_setup_ctrl(ctrl, true);
+	if (ret)
+		goto out_uninit_ctrl;
+
+	dev_info(ctrl->ctrl.device, "new ctrl: NQN \"%s\", addr %pISpcs\n",
+		ctrl->ctrl.opts->subsysnqn, &ctrl->addr);
+
+	nvme_get_ctrl(&ctrl->ctrl);
+
+	mutex_lock(&nvme_rdma_ctrl_mutex);
+	list_add_tail(&ctrl->list, &nvme_rdma_ctrl_list);
+	mutex_unlock(&nvme_rdma_ctrl_mutex);
+
+	return &ctrl->ctrl;
+
+out_uninit_ctrl:
+	nvme_uninit_ctrl(&ctrl->ctrl);
+	nvme_put_ctrl(&ctrl->ctrl);
+	if (ret > 0)
+		ret = -EIO;
+	return ERR_PTR(ret);
+out_kfree_queues:
+	kfree(ctrl->queues);
+out_free_ctrl:
+	kfree(ctrl);
+	return ERR_PTR(ret);
+}
+
+static struct nvmf_transport_ops nvme_rdma_transport = {
+	.name		= "rdma",
+	.module		= THIS_MODULE,
+	.required_opts	= NVMF_OPT_TRADDR,
+	.allowed_opts	= NVMF_OPT_TRSVCID | NVMF_OPT_RECONNECT_DELAY |
+			  NVMF_OPT_HOST_TRADDR | NVMF_OPT_CTRL_LOSS_TMO,
+	.create_ctrl	= nvme_rdma_create_ctrl,
+};
+
+static void nvme_rdma_remove_one(struct ib_device *ib_device, void *client_data)
+{
+	struct nvme_rdma_ctrl *ctrl;
+	struct nvme_rdma_device *ndev;
+	bool found = false;
+
+	mutex_lock(&device_list_mutex);
+	list_for_each_entry(ndev, &device_list, entry) {
+		if (ndev->dev == ib_device) {
+			found = true;
+			break;
+		}
+	}
+	mutex_unlock(&device_list_mutex);
+
+	if (!found)
+		return;
+
+	/* Delete all controllers using this device */
+	mutex_lock(&nvme_rdma_ctrl_mutex);
+	list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
+		if (ctrl->device->dev != ib_device)
+			continue;
+		nvme_delete_ctrl(&ctrl->ctrl);
+	}
+	mutex_unlock(&nvme_rdma_ctrl_mutex);
+
+	flush_workqueue(nvme_delete_wq);
+}
+
+static struct ib_client nvme_rdma_ib_client = {
+	.name   = "nvme_rdma",
+	.remove = nvme_rdma_remove_one
+};
+
+static int __init nvme_rdma_init_module(void)
+{
+	int ret;
+
+	ret = ib_register_client(&nvme_rdma_ib_client);
+	if (ret)
+		return ret;
+
+	ret = nvmf_register_transport(&nvme_rdma_transport);
+	if (ret)
+		goto err_unreg_client;
+
+	return 0;
+
+err_unreg_client:
+	ib_unregister_client(&nvme_rdma_ib_client);
+	return ret;
+}
+
+static void __exit nvme_rdma_cleanup_module(void)
+{
+	nvmf_unregister_transport(&nvme_rdma_transport);
+	ib_unregister_client(&nvme_rdma_ib_client);
+}
+
+module_init(nvme_rdma_init_module);
+module_exit(nvme_rdma_cleanup_module);
+
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/nvme/host/trace.c b/drivers/nvme/host/trace.c
new file mode 100644
index 000000000..25b0e310f
--- /dev/null
+++ b/drivers/nvme/host/trace.c
@@ -0,0 +1,141 @@
+/*
+ * NVM Express device driver tracepoints
+ * Copyright (c) 2018 Johannes Thumshirn, SUSE Linux GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <asm/unaligned.h>
+#include "trace.h"
+
+static const char *nvme_trace_create_sq(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u16 sqid = get_unaligned_le16(cdw10);
+	u16 qsize = get_unaligned_le16(cdw10 + 2);
+	u16 sq_flags = get_unaligned_le16(cdw10 + 4);
+	u16 cqid = get_unaligned_le16(cdw10 + 6);
+
+
+	trace_seq_printf(p, "sqid=%u, qsize=%u, sq_flags=0x%x, cqid=%u",
+			 sqid, qsize, sq_flags, cqid);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_create_cq(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u16 cqid = get_unaligned_le16(cdw10);
+	u16 qsize = get_unaligned_le16(cdw10 + 2);
+	u16 cq_flags = get_unaligned_le16(cdw10 + 4);
+	u16 irq_vector = get_unaligned_le16(cdw10 + 6);
+
+	trace_seq_printf(p, "cqid=%u, qsize=%u, cq_flags=0x%x, irq_vector=%u",
+			 cqid, qsize, cq_flags, irq_vector);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_admin_identify(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u8 cns = cdw10[0];
+	u16 ctrlid = get_unaligned_le16(cdw10 + 2);
+
+	trace_seq_printf(p, "cns=%u, ctrlid=%u", cns, ctrlid);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+
+
+static const char *nvme_trace_read_write(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u64 slba = get_unaligned_le64(cdw10);
+	u16 length = get_unaligned_le16(cdw10 + 8);
+	u16 control = get_unaligned_le16(cdw10 + 10);
+	u32 dsmgmt = get_unaligned_le32(cdw10 + 12);
+	u32 reftag = get_unaligned_le32(cdw10 +  16);
+
+	trace_seq_printf(p,
+			 "slba=%llu, len=%u, ctrl=0x%x, dsmgmt=%u, reftag=%u",
+			 slba, length, control, dsmgmt, reftag);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_dsm(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "nr=%u, attributes=%u",
+			 get_unaligned_le32(cdw10),
+			 get_unaligned_le32(cdw10 + 4));
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_common(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "cdw10=%*ph", 24, cdw10);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *nvme_trace_parse_admin_cmd(struct trace_seq *p,
+				       u8 opcode, u8 *cdw10)
+{
+	switch (opcode) {
+	case nvme_admin_create_sq:
+		return nvme_trace_create_sq(p, cdw10);
+	case nvme_admin_create_cq:
+		return nvme_trace_create_cq(p, cdw10);
+	case nvme_admin_identify:
+		return nvme_trace_admin_identify(p, cdw10);
+	default:
+		return nvme_trace_common(p, cdw10);
+	}
+}
+
+const char *nvme_trace_parse_nvm_cmd(struct trace_seq *p,
+				     u8 opcode, u8 *cdw10)
+{
+	switch (opcode) {
+	case nvme_cmd_read:
+	case nvme_cmd_write:
+	case nvme_cmd_write_zeroes:
+		return nvme_trace_read_write(p, cdw10);
+	case nvme_cmd_dsm:
+		return nvme_trace_dsm(p, cdw10);
+	default:
+		return nvme_trace_common(p, cdw10);
+	}
+}
+
+const char *nvme_trace_disk_name(struct trace_seq *p, char *name)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	if (*name)
+		trace_seq_printf(p, "disk=%s, ", name);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
diff --git a/drivers/nvme/host/trace.h b/drivers/nvme/host/trace.h
new file mode 100644
index 000000000..a490790d6
--- /dev/null
+++ b/drivers/nvme/host/trace.h
@@ -0,0 +1,167 @@
+/*
+ * NVM Express device driver tracepoints
+ * Copyright (c) 2018 Johannes Thumshirn, SUSE Linux GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM nvme
+
+#if !defined(_TRACE_NVME_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_NVME_H
+
+#include <linux/nvme.h>
+#include <linux/tracepoint.h>
+#include <linux/trace_seq.h>
+
+#include "nvme.h"
+
+#define nvme_admin_opcode_name(opcode)	{ opcode, #opcode }
+#define show_admin_opcode_name(val)					\
+	__print_symbolic(val,						\
+		nvme_admin_opcode_name(nvme_admin_delete_sq),		\
+		nvme_admin_opcode_name(nvme_admin_create_sq),		\
+		nvme_admin_opcode_name(nvme_admin_get_log_page),	\
+		nvme_admin_opcode_name(nvme_admin_delete_cq),		\
+		nvme_admin_opcode_name(nvme_admin_create_cq),		\
+		nvme_admin_opcode_name(nvme_admin_identify),		\
+		nvme_admin_opcode_name(nvme_admin_abort_cmd),		\
+		nvme_admin_opcode_name(nvme_admin_set_features),	\
+		nvme_admin_opcode_name(nvme_admin_get_features),	\
+		nvme_admin_opcode_name(nvme_admin_async_event),		\
+		nvme_admin_opcode_name(nvme_admin_ns_mgmt),		\
+		nvme_admin_opcode_name(nvme_admin_activate_fw),		\
+		nvme_admin_opcode_name(nvme_admin_download_fw),		\
+		nvme_admin_opcode_name(nvme_admin_ns_attach),		\
+		nvme_admin_opcode_name(nvme_admin_keep_alive),		\
+		nvme_admin_opcode_name(nvme_admin_directive_send),	\
+		nvme_admin_opcode_name(nvme_admin_directive_recv),	\
+		nvme_admin_opcode_name(nvme_admin_dbbuf),		\
+		nvme_admin_opcode_name(nvme_admin_format_nvm),		\
+		nvme_admin_opcode_name(nvme_admin_security_send),	\
+		nvme_admin_opcode_name(nvme_admin_security_recv),	\
+		nvme_admin_opcode_name(nvme_admin_sanitize_nvm))
+
+#define nvme_opcode_name(opcode)	{ opcode, #opcode }
+#define show_nvm_opcode_name(val)				\
+	__print_symbolic(val,					\
+		nvme_opcode_name(nvme_cmd_flush),		\
+		nvme_opcode_name(nvme_cmd_write),		\
+		nvme_opcode_name(nvme_cmd_read),		\
+		nvme_opcode_name(nvme_cmd_write_uncor),		\
+		nvme_opcode_name(nvme_cmd_compare),		\
+		nvme_opcode_name(nvme_cmd_write_zeroes),	\
+		nvme_opcode_name(nvme_cmd_dsm),			\
+		nvme_opcode_name(nvme_cmd_resv_register),	\
+		nvme_opcode_name(nvme_cmd_resv_report),		\
+		nvme_opcode_name(nvme_cmd_resv_acquire),	\
+		nvme_opcode_name(nvme_cmd_resv_release))
+
+#define show_opcode_name(qid, opcode)					\
+	(qid ? show_nvm_opcode_name(opcode) : show_admin_opcode_name(opcode))
+
+const char *nvme_trace_parse_admin_cmd(struct trace_seq *p, u8 opcode,
+		u8 *cdw10);
+const char *nvme_trace_parse_nvm_cmd(struct trace_seq *p, u8 opcode,
+		u8 *cdw10);
+
+#define parse_nvme_cmd(qid, opcode, cdw10) 			\
+	(qid ?							\
+	 nvme_trace_parse_nvm_cmd(p, opcode, cdw10) : 		\
+	 nvme_trace_parse_admin_cmd(p, opcode, cdw10))
+
+const char *nvme_trace_disk_name(struct trace_seq *p, char *name);
+#define __print_disk_name(name)				\
+	nvme_trace_disk_name(p, name)
+
+#ifndef TRACE_HEADER_MULTI_READ
+static inline void __assign_disk_name(char *name, struct gendisk *disk)
+{
+	if (disk)
+		memcpy(name, disk->disk_name, DISK_NAME_LEN);
+	else
+		memset(name, 0, DISK_NAME_LEN);
+}
+#endif
+
+TRACE_EVENT(nvme_setup_cmd,
+	    TP_PROTO(struct request *req, struct nvme_command *cmd),
+	    TP_ARGS(req, cmd),
+	    TP_STRUCT__entry(
+		__array(char, disk, DISK_NAME_LEN)
+		__field(int, ctrl_id)
+		__field(int, qid)
+		__field(u8, opcode)
+		__field(u8, flags)
+		__field(u16, cid)
+		__field(u32, nsid)
+		__field(u64, metadata)
+		__array(u8, cdw10, 24)
+	    ),
+	    TP_fast_assign(
+		__entry->ctrl_id = nvme_req(req)->ctrl->instance;
+		__entry->qid = nvme_req_qid(req);
+		__entry->opcode = cmd->common.opcode;
+		__entry->flags = cmd->common.flags;
+		__entry->cid = cmd->common.command_id;
+		__entry->nsid = le32_to_cpu(cmd->common.nsid);
+		__entry->metadata = le64_to_cpu(cmd->common.metadata);
+		__assign_disk_name(__entry->disk, req->rq_disk);
+		memcpy(__entry->cdw10, cmd->common.cdw10,
+		       sizeof(__entry->cdw10));
+	    ),
+	    TP_printk("nvme%d: %sqid=%d, cmdid=%u, nsid=%u, flags=0x%x, meta=0x%llx, cmd=(%s %s)",
+		      __entry->ctrl_id, __print_disk_name(__entry->disk),
+		      __entry->qid, __entry->cid, __entry->nsid,
+		      __entry->flags, __entry->metadata,
+		      show_opcode_name(__entry->qid, __entry->opcode),
+		      parse_nvme_cmd(__entry->qid, __entry->opcode, __entry->cdw10))
+);
+
+TRACE_EVENT(nvme_complete_rq,
+	    TP_PROTO(struct request *req),
+	    TP_ARGS(req),
+	    TP_STRUCT__entry(
+		__array(char, disk, DISK_NAME_LEN)
+		__field(int, ctrl_id)
+		__field(int, qid)
+		__field(int, cid)
+		__field(u64, result)
+		__field(u8, retries)
+		__field(u8, flags)
+		__field(u16, status)
+	    ),
+	    TP_fast_assign(
+		__entry->ctrl_id = nvme_req(req)->ctrl->instance;
+		__entry->qid = nvme_req_qid(req);
+		__entry->cid = req->tag;
+		__entry->result = le64_to_cpu(nvme_req(req)->result.u64);
+		__entry->retries = nvme_req(req)->retries;
+		__entry->flags = nvme_req(req)->flags;
+		__entry->status = nvme_req(req)->status;
+		__assign_disk_name(__entry->disk, req->rq_disk);
+	    ),
+	    TP_printk("nvme%d: %sqid=%d, cmdid=%u, res=%llu, retries=%u, flags=0x%x, status=%u",
+		      __entry->ctrl_id, __print_disk_name(__entry->disk),
+		      __entry->qid, __entry->cid, __entry->result,
+		      __entry->retries, __entry->flags, __entry->status)
+
+);
+
+#endif /* _TRACE_NVME_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>