Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3982 insertions, 0 deletions

diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
new file mode 100644
index 000000000..177a365b8
--- /dev/null
+++ b/drivers/nvme/host/fc.c
@@ -0,0 +1,3982 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016 Avago Technologies.  All rights reserved.
+ */
+#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 <linux/overflow.h>
+#include <linux/blk-cgroup.h>
+#include "nvme.h"
+#include "fabrics.h"
+#include <linux/nvme-fc-driver.h>
+#include <linux/nvme-fc.h>
+#include "fc.h"
+#include <scsi/scsi_transport_fc.h>
+#include <linux/blk-mq-pci.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 */
+#define NVME_FC_DEFAULT_RECONNECT_TMO	2	/* delay between reconnects
+						 * when connected and a
+						 * connection failure.
+						 */
+
+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;
+};
+
+struct nvmefc_ls_rcv_op {
+	struct nvme_fc_rport		*rport;
+	struct nvmefc_ls_rsp		*lsrsp;
+	union nvmefc_ls_requests	*rqstbuf;
+	union nvmefc_ls_responses	*rspbuf;
+	u16				rqstdatalen;
+	bool				handled;
+	dma_addr_t			rspdma;
+	struct list_head		lsrcv_list;	/* rport->ls_rcv_list */
+} __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
+
+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_fcp_op_w_sgl {
+	struct nvme_fc_fcp_op	op;
+	struct scatterlist	sgl[NVME_INLINE_SG_CNT];
+	uint8_t			priv[];
+};
+
+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 list_head		ls_rcv_list;
+	struct list_head		disc_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;
+	struct work_struct		lsrcv_work;
+} __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
+
+/* fc_ctrl flags values - specified as bit positions */
+#define ASSOC_ACTIVE		0
+#define ASSOC_FAILED		1
+#define FCCTRL_TERMIO		2
+
+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;
+	u64			association_id;
+	struct nvmefc_ls_rcv_op	*rcv_disconn;
+
+	struct list_head	ctrl_list;	/* rport->ctrl_list */
+
+	struct blk_mq_tag_set	admin_tag_set;
+	struct blk_mq_tag_set	tag_set;
+
+	struct work_struct	ioerr_work;
+	struct delayed_work	connect_work;
+
+	struct kref		ref;
+	unsigned long		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;
+
+static bool nvme_fc_waiting_to_unload;
+static DECLARE_COMPLETION(nvme_fc_unload_proceed);
+
+/*
+ * These items are short-term. They will eventually be moved into
+ * a generic FC class. See comments in module init.
+ */
+static struct device *fc_udev_device;
+
+static void nvme_fc_complete_rq(struct request *rq);
+
+/* *********************** 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_handle_ls_rqst_work(struct work_struct *work);
+
+
+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);
+	if (nvme_fc_waiting_to_unload && list_empty(&nvme_fc_lport_list))
+		complete(&nvme_fc_unload_proceed);
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	ida_free(&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
+ * @portptr:   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_alloc(&nvme_fc_local_port_cnt, 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);
+	if (template->local_priv_sz)
+		newrec->localport.private = &newrec[1];
+	else
+		newrec->localport.private = NULL;
+	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_free(&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.
+ * @portptr: 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);
+
+	WARN_ON(!list_empty(&rport->disc_list));
+	ida_free(&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
+ * @portptr:   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_alloc(&lport->endp_cnt, 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);
+	INIT_LIST_HEAD(&newrec->disc_list);
+	kref_init(&newrec->ref);
+	atomic_set(&newrec->act_ctrl_cnt, 0);
+	spin_lock_init(&newrec->lock);
+	newrec->remoteport.localport = &lport->localport;
+	INIT_LIST_HEAD(&newrec->ls_rcv_list);
+	newrec->dev = lport->dev;
+	newrec->lport = lport;
+	if (lport->ops->remote_priv_sz)
+		newrec->remoteport.private = &newrec[1];
+	else
+		newrec->remoteport.private = NULL;
+	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);
+	INIT_WORK(&newrec->lsrcv_work, nvme_fc_handle_ls_rqst_work);
+
+	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:
+	case NVME_CTRL_DELETING_NOIO:
+	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.
+ * @portptr: 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_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg);
+
+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);
+}
+
+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;
+	unsigned long flags;
+	int ret, fcret = 0;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			 sizeof(*assoc_rqst) + sizeof(*assoc_acc) +
+			 ctrl->lport->ops->lsrqst_priv_sz), GFP_KERNEL);
+	if (!lsop) {
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: send Create Association failed: ENOMEM\n",
+			ctrl->cnum);
+		ret = -ENOMEM;
+		goto out_no_memory;
+	}
+
+	assoc_rqst = (struct fcnvme_ls_cr_assoc_rqst *)&lsop[1];
+	assoc_acc = (struct fcnvme_ls_cr_assoc_acc *)&assoc_rqst[1];
+	lsreq = &lsop->ls_req;
+	if (ctrl->lport->ops->lsrqst_priv_sz)
+		lsreq->private = &assoc_acc[1];
+	else
+		lsreq->private = NULL;
+
+	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_LS_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 Create Association LS failed: %s\n",
+			queue->qnum, validation_errors[fcret]);
+	} else {
+		spin_lock_irqsave(&ctrl->lock, flags);
+		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);
+		spin_unlock_irqrestore(&ctrl->lock, 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) +
+			 sizeof(*conn_rqst) + sizeof(*conn_acc) +
+			 ctrl->lport->ops->lsrqst_priv_sz), GFP_KERNEL);
+	if (!lsop) {
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: send Create Connection failed: ENOMEM\n",
+			ctrl->cnum);
+		ret = -ENOMEM;
+		goto out_no_memory;
+	}
+
+	conn_rqst = (struct fcnvme_ls_cr_conn_rqst *)&lsop[1];
+	conn_acc = (struct fcnvme_ls_cr_conn_acc *)&conn_rqst[1];
+	lsreq = &lsop->ls_req;
+	if (ctrl->lport->ops->lsrqst_priv_sz)
+		lsreq->private = (void *)&conn_acc[1];
+	else
+		lsreq->private = NULL;
+
+	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_LS_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 Create I/O Connection LS 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 I/O queue 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 initiator 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_assoc_rqst *discon_rqst;
+	struct fcnvme_ls_disconnect_assoc_acc *discon_acc;
+	struct nvmefc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	int ret;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			sizeof(*discon_rqst) + sizeof(*discon_acc) +
+			ctrl->lport->ops->lsrqst_priv_sz), GFP_KERNEL);
+	if (!lsop) {
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: send Disconnect Association "
+			"failed: ENOMEM\n",
+			ctrl->cnum);
+		return;
+	}
+
+	discon_rqst = (struct fcnvme_ls_disconnect_assoc_rqst *)&lsop[1];
+	discon_acc = (struct fcnvme_ls_disconnect_assoc_acc *)&discon_rqst[1];
+	lsreq = &lsop->ls_req;
+	if (ctrl->lport->ops->lsrqst_priv_sz)
+		lsreq->private = (void *)&discon_acc[1];
+	else
+		lsreq->private = NULL;
+
+	nvmefc_fmt_lsreq_discon_assoc(lsreq, discon_rqst, discon_acc,
+				ctrl->association_id);
+
+	ret = nvme_fc_send_ls_req_async(ctrl->rport, lsop,
+				nvme_fc_disconnect_assoc_done);
+	if (ret)
+		kfree(lsop);
+}
+
+static void
+nvme_fc_xmt_ls_rsp_done(struct nvmefc_ls_rsp *lsrsp)
+{
+	struct nvmefc_ls_rcv_op *lsop = lsrsp->nvme_fc_private;
+	struct nvme_fc_rport *rport = lsop->rport;
+	struct nvme_fc_lport *lport = rport->lport;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rport->lock, flags);
+	list_del(&lsop->lsrcv_list);
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	fc_dma_sync_single_for_cpu(lport->dev, lsop->rspdma,
+				sizeof(*lsop->rspbuf), DMA_TO_DEVICE);
+	fc_dma_unmap_single(lport->dev, lsop->rspdma,
+			sizeof(*lsop->rspbuf), DMA_TO_DEVICE);
+
+	kfree(lsop);
+
+	nvme_fc_rport_put(rport);
+}
+
+static void
+nvme_fc_xmt_ls_rsp(struct nvmefc_ls_rcv_op *lsop)
+{
+	struct nvme_fc_rport *rport = lsop->rport;
+	struct nvme_fc_lport *lport = rport->lport;
+	struct fcnvme_ls_rqst_w0 *w0 = &lsop->rqstbuf->w0;
+	int ret;
+
+	fc_dma_sync_single_for_device(lport->dev, lsop->rspdma,
+				  sizeof(*lsop->rspbuf), DMA_TO_DEVICE);
+
+	ret = lport->ops->xmt_ls_rsp(&lport->localport, &rport->remoteport,
+				     lsop->lsrsp);
+	if (ret) {
+		dev_warn(lport->dev,
+			"LLDD rejected LS RSP xmt: LS %d status %d\n",
+			w0->ls_cmd, ret);
+		nvme_fc_xmt_ls_rsp_done(lsop->lsrsp);
+		return;
+	}
+}
+
+static struct nvme_fc_ctrl *
+nvme_fc_match_disconn_ls(struct nvme_fc_rport *rport,
+		      struct nvmefc_ls_rcv_op *lsop)
+{
+	struct fcnvme_ls_disconnect_assoc_rqst *rqst =
+					&lsop->rqstbuf->rq_dis_assoc;
+	struct nvme_fc_ctrl *ctrl, *ret = NULL;
+	struct nvmefc_ls_rcv_op *oldls = NULL;
+	u64 association_id = be64_to_cpu(rqst->associd.association_id);
+	unsigned long flags;
+
+	spin_lock_irqsave(&rport->lock, flags);
+
+	list_for_each_entry(ctrl, &rport->ctrl_list, ctrl_list) {
+		if (!nvme_fc_ctrl_get(ctrl))
+			continue;
+		spin_lock(&ctrl->lock);
+		if (association_id == ctrl->association_id) {
+			oldls = ctrl->rcv_disconn;
+			ctrl->rcv_disconn = lsop;
+			ret = ctrl;
+		}
+		spin_unlock(&ctrl->lock);
+		if (ret)
+			/* leave the ctrl get reference */
+			break;
+		nvme_fc_ctrl_put(ctrl);
+	}
+
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	/* transmit a response for anything that was pending */
+	if (oldls) {
+		dev_info(rport->lport->dev,
+			"NVME-FC{%d}: Multiple Disconnect Association "
+			"LS's received\n", ctrl->cnum);
+		/* overwrite good response with bogus failure */
+		oldls->lsrsp->rsplen = nvme_fc_format_rjt(oldls->rspbuf,
+						sizeof(*oldls->rspbuf),
+						rqst->w0.ls_cmd,
+						FCNVME_RJT_RC_UNAB,
+						FCNVME_RJT_EXP_NONE, 0);
+		nvme_fc_xmt_ls_rsp(oldls);
+	}
+
+	return ret;
+}
+
+/*
+ * returns true to mean LS handled and ls_rsp can be sent
+ * returns false to defer ls_rsp xmt (will be done as part of
+ *     association termination)
+ */
+static bool
+nvme_fc_ls_disconnect_assoc(struct nvmefc_ls_rcv_op *lsop)
+{
+	struct nvme_fc_rport *rport = lsop->rport;
+	struct fcnvme_ls_disconnect_assoc_rqst *rqst =
+					&lsop->rqstbuf->rq_dis_assoc;
+	struct fcnvme_ls_disconnect_assoc_acc *acc =
+					&lsop->rspbuf->rsp_dis_assoc;
+	struct nvme_fc_ctrl *ctrl = NULL;
+	int ret = 0;
+
+	memset(acc, 0, sizeof(*acc));
+
+	ret = nvmefc_vldt_lsreq_discon_assoc(lsop->rqstdatalen, rqst);
+	if (!ret) {
+		/* match an active association */
+		ctrl = nvme_fc_match_disconn_ls(rport, lsop);
+		if (!ctrl)
+			ret = VERR_NO_ASSOC;
+	}
+
+	if (ret) {
+		dev_info(rport->lport->dev,
+			"Disconnect LS failed: %s\n",
+			validation_errors[ret]);
+		lsop->lsrsp->rsplen = nvme_fc_format_rjt(acc,
+					sizeof(*acc), rqst->w0.ls_cmd,
+					(ret == VERR_NO_ASSOC) ?
+						FCNVME_RJT_RC_INV_ASSOC :
+						FCNVME_RJT_RC_LOGIC,
+					FCNVME_RJT_EXP_NONE, 0);
+		return true;
+	}
+
+	/* format an ACCept response */
+
+	lsop->lsrsp->rsplen = sizeof(*acc);
+
+	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_ls_disconnect_assoc_acc)),
+			FCNVME_LS_DISCONNECT_ASSOC);
+
+	/*
+	 * the transmit of the response will occur after the exchanges
+	 * for the association have been ABTS'd by
+	 * nvme_fc_delete_association().
+	 */
+
+	/* fail the association */
+	nvme_fc_error_recovery(ctrl, "Disconnect Association LS received");
+
+	/* release the reference taken by nvme_fc_match_disconn_ls() */
+	nvme_fc_ctrl_put(ctrl);
+
+	return false;
+}
+
+/*
+ * Actual Processing routine for received FC-NVME LS Requests from the LLD
+ * returns true if a response should be sent afterward, false if rsp will
+ * be sent asynchronously.
+ */
+static bool
+nvme_fc_handle_ls_rqst(struct nvmefc_ls_rcv_op *lsop)
+{
+	struct fcnvme_ls_rqst_w0 *w0 = &lsop->rqstbuf->w0;
+	bool ret = true;
+
+	lsop->lsrsp->nvme_fc_private = lsop;
+	lsop->lsrsp->rspbuf = lsop->rspbuf;
+	lsop->lsrsp->rspdma = lsop->rspdma;
+	lsop->lsrsp->done = nvme_fc_xmt_ls_rsp_done;
+	/* Be preventative. handlers will later set to valid length */
+	lsop->lsrsp->rsplen = 0;
+
+	/*
+	 * handlers:
+	 *   parse request input, execute the request, and format the
+	 *   LS response
+	 */
+	switch (w0->ls_cmd) {
+	case FCNVME_LS_DISCONNECT_ASSOC:
+		ret = nvme_fc_ls_disconnect_assoc(lsop);
+		break;
+	case FCNVME_LS_DISCONNECT_CONN:
+		lsop->lsrsp->rsplen = nvme_fc_format_rjt(lsop->rspbuf,
+				sizeof(*lsop->rspbuf), w0->ls_cmd,
+				FCNVME_RJT_RC_UNSUP, FCNVME_RJT_EXP_NONE, 0);
+		break;
+	case FCNVME_LS_CREATE_ASSOCIATION:
+	case FCNVME_LS_CREATE_CONNECTION:
+		lsop->lsrsp->rsplen = nvme_fc_format_rjt(lsop->rspbuf,
+				sizeof(*lsop->rspbuf), w0->ls_cmd,
+				FCNVME_RJT_RC_LOGIC, FCNVME_RJT_EXP_NONE, 0);
+		break;
+	default:
+		lsop->lsrsp->rsplen = nvme_fc_format_rjt(lsop->rspbuf,
+				sizeof(*lsop->rspbuf), w0->ls_cmd,
+				FCNVME_RJT_RC_INVAL, FCNVME_RJT_EXP_NONE, 0);
+		break;
+	}
+
+	return(ret);
+}
+
+static void
+nvme_fc_handle_ls_rqst_work(struct work_struct *work)
+{
+	struct nvme_fc_rport *rport =
+		container_of(work, struct nvme_fc_rport, lsrcv_work);
+	struct fcnvme_ls_rqst_w0 *w0;
+	struct nvmefc_ls_rcv_op *lsop;
+	unsigned long flags;
+	bool sendrsp;
+
+restart:
+	sendrsp = true;
+	spin_lock_irqsave(&rport->lock, flags);
+	list_for_each_entry(lsop, &rport->ls_rcv_list, lsrcv_list) {
+		if (lsop->handled)
+			continue;
+
+		lsop->handled = true;
+		if (rport->remoteport.port_state == FC_OBJSTATE_ONLINE) {
+			spin_unlock_irqrestore(&rport->lock, flags);
+			sendrsp = nvme_fc_handle_ls_rqst(lsop);
+		} else {
+			spin_unlock_irqrestore(&rport->lock, flags);
+			w0 = &lsop->rqstbuf->w0;
+			lsop->lsrsp->rsplen = nvme_fc_format_rjt(
+						lsop->rspbuf,
+						sizeof(*lsop->rspbuf),
+						w0->ls_cmd,
+						FCNVME_RJT_RC_UNAB,
+						FCNVME_RJT_EXP_NONE, 0);
+		}
+		if (sendrsp)
+			nvme_fc_xmt_ls_rsp(lsop);
+		goto restart;
+	}
+	spin_unlock_irqrestore(&rport->lock, flags);
+}
+
+/**
+ * nvme_fc_rcv_ls_req - transport entry point called by an LLDD
+ *                       upon the reception of a NVME LS request.
+ *
+ * The nvme-fc layer will copy payload to an internal structure for
+ * processing.  As such, upon completion of the routine, the LLDD may
+ * immediately free/reuse the LS request buffer passed in the call.
+ *
+ * If this routine returns error, the LLDD should abort the exchange.
+ *
+ * @portptr:    pointer to the (registered) remote port that the LS
+ *              was received from. The remoteport is associated with
+ *              a specific localport.
+ * @lsrsp:      pointer to a nvmefc_ls_rsp response structure to be
+ *              used to reference the exchange corresponding to the LS
+ *              when issuing an ls response.
+ * @lsreqbuf:   pointer to the buffer containing the LS Request
+ * @lsreqbuf_len: length, in bytes, of the received LS request
+ */
+int
+nvme_fc_rcv_ls_req(struct nvme_fc_remote_port *portptr,
+			struct nvmefc_ls_rsp *lsrsp,
+			void *lsreqbuf, u32 lsreqbuf_len)
+{
+	struct nvme_fc_rport *rport = remoteport_to_rport(portptr);
+	struct nvme_fc_lport *lport = rport->lport;
+	struct fcnvme_ls_rqst_w0 *w0 = (struct fcnvme_ls_rqst_w0 *)lsreqbuf;
+	struct nvmefc_ls_rcv_op *lsop;
+	unsigned long flags;
+	int ret;
+
+	nvme_fc_rport_get(rport);
+
+	/* validate there's a routine to transmit a response */
+	if (!lport->ops->xmt_ls_rsp) {
+		dev_info(lport->dev,
+			"RCV %s LS failed: no LLDD xmt_ls_rsp\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		ret = -EINVAL;
+		goto out_put;
+	}
+
+	if (lsreqbuf_len > sizeof(union nvmefc_ls_requests)) {
+		dev_info(lport->dev,
+			"RCV %s LS failed: payload too large\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		ret = -E2BIG;
+		goto out_put;
+	}
+
+	lsop = kzalloc(sizeof(*lsop) +
+			sizeof(union nvmefc_ls_requests) +
+			sizeof(union nvmefc_ls_responses),
+			GFP_KERNEL);
+	if (!lsop) {
+		dev_info(lport->dev,
+			"RCV %s LS failed: No memory\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		ret = -ENOMEM;
+		goto out_put;
+	}
+	lsop->rqstbuf = (union nvmefc_ls_requests *)&lsop[1];
+	lsop->rspbuf = (union nvmefc_ls_responses *)&lsop->rqstbuf[1];
+
+	lsop->rspdma = fc_dma_map_single(lport->dev, lsop->rspbuf,
+					sizeof(*lsop->rspbuf),
+					DMA_TO_DEVICE);
+	if (fc_dma_mapping_error(lport->dev, lsop->rspdma)) {
+		dev_info(lport->dev,
+			"RCV %s LS failed: DMA mapping failure\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		ret = -EFAULT;
+		goto out_free;
+	}
+
+	lsop->rport = rport;
+	lsop->lsrsp = lsrsp;
+
+	memcpy(lsop->rqstbuf, lsreqbuf, lsreqbuf_len);
+	lsop->rqstdatalen = lsreqbuf_len;
+
+	spin_lock_irqsave(&rport->lock, flags);
+	if (rport->remoteport.port_state != FC_OBJSTATE_ONLINE) {
+		spin_unlock_irqrestore(&rport->lock, flags);
+		ret = -ENOTCONN;
+		goto out_unmap;
+	}
+	list_add_tail(&lsop->lsrcv_list, &rport->ls_rcv_list);
+	spin_unlock_irqrestore(&rport->lock, flags);
+
+	schedule_work(&rport->lsrcv_work);
+
+	return 0;
+
+out_unmap:
+	fc_dma_unmap_single(lport->dev, lsop->rspdma,
+			sizeof(*lsop->rspbuf), DMA_TO_DEVICE);
+out_free:
+	kfree(lsop);
+out_put:
+	nvme_fc_rport_put(rport);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_fc_rcv_ls_req);
+
+
+/* *********************** NVME Ctrl Routines **************************** */
+
+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(to_fc_ctrl(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 (test_bit(FCCTRL_TERMIO, &ctrl->flags)) {
+		op->flags |= FCOP_FLAGS_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 (test_bit(FCCTRL_TERMIO, &ctrl->flags) &&
+		    op->flags & FCOP_FLAGS_TERMIO) {
+			if (!--ctrl->iocnt)
+				wake_up(&ctrl->ioabort_wait);
+		}
+		spin_unlock_irqrestore(&ctrl->lock, flags);
+	}
+}
+
+static void
+nvme_fc_ctrl_ioerr_work(struct work_struct *work)
+{
+	struct nvme_fc_ctrl *ctrl =
+			container_of(work, struct nvme_fc_ctrl, ioerr_work);
+
+	nvme_fc_error_recovery(ctrl, "transport detected io error");
+}
+
+/*
+ * nvme_fc_io_getuuid - Routine called to get the appid field
+ * associated with request by the lldd
+ * @req:IO request from nvme fc to driver
+ * Returns: UUID if there is an appid associated with VM or
+ * NULL if the user/libvirt has not set the appid to VM
+ */
+char *nvme_fc_io_getuuid(struct nvmefc_fcp_req *req)
+{
+	struct nvme_fc_fcp_op *op = fcp_req_to_fcp_op(req);
+	struct request *rq = op->rq;
+
+	if (!IS_ENABLED(CONFIG_BLK_CGROUP_FC_APPID) || !rq || !rq->bio)
+		return NULL;
+	return blkcg_get_fc_appid(rq->bio);
+}
+EXPORT_SYMBOL_GPL(nvme_fc_io_getuuid);
+
+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_HOST_ABORTED_CMD << 1);
+	else if (freq->status) {
+		status = cpu_to_le16(NVME_SC_HOST_PATH_ERROR << 1);
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: io failed due to lldd error %d\n",
+			ctrl->cnum, freq->status);
+	}
+
+	/*
+	 * 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_HOST_PATH_ERROR << 1);
+			dev_info(ctrl->ctrl.device,
+				"NVME-FC{%d}: io failed due to bad transfer "
+				"length: %d vs expected %d\n",
+				ctrl->cnum, freq->transferred_length,
+				be32_to_cpu(op->cmd_iu.data_len));
+			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.ersp_result ||
+			     sqe->common.command_id != cqe->command_id)) {
+			status = cpu_to_le16(NVME_SC_HOST_PATH_ERROR << 1);
+			dev_info(ctrl->ctrl.device,
+				"NVME-FC{%d}: io failed due to bad NVMe_ERSP: "
+				"iu len %d, xfr len %d vs %d, status code "
+				"%d, cmdid %d vs %d\n",
+				ctrl->cnum, be16_to_cpu(op->rsp_iu.iu_len),
+				be32_to_cpu(op->rsp_iu.xfrd_len),
+				freq->transferred_length,
+				op->rsp_iu.ersp_result,
+				sqe->common.command_id,
+				cqe->command_id);
+			goto done;
+		}
+		result = cqe->result;
+		status = cqe->status;
+		break;
+
+	default:
+		status = cpu_to_le16(NVME_SC_HOST_PATH_ERROR << 1);
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: io failed due to odd NVMe_xRSP iu "
+			"len %d\n",
+			ctrl->cnum, freq->rcv_rsplen);
+		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);
+	if (!nvme_try_complete_req(rq, status, result))
+		nvme_fc_complete_rq(rq);
+
+check_error:
+	if (terminate_assoc && ctrl->ctrl.state != NVME_CTRL_RESETTING)
+		queue_work(nvme_reset_wq, &ctrl->ioerr_work);
+}
+
+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_fcp_op_w_sgl *op_w_sgl =
+		container_of(op, typeof(*op_w_sgl), op);
+	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->ctrl = ctrl;
+	op->queue = queue;
+	op->rq = rq;
+	op->rqno = rqno;
+
+	cmdiu->format_id = NVME_CMD_FORMAT_ID;
+	cmdiu->fc_id = NVME_CMD_FC_ID;
+	cmdiu->iu_len = cpu_to_be16(sizeof(*cmdiu) / sizeof(u32));
+	if (queue->qnum)
+		cmdiu->rsv_cat = fccmnd_set_cat_css(0,
+					(NVME_CC_CSS_NVM >> NVME_CC_CSS_SHIFT));
+	else
+		cmdiu->rsv_cat = fccmnd_set_cat_admin(0);
+
+	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 = to_fc_ctrl(set->driver_data);
+	struct nvme_fcp_op_w_sgl *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];
+	int res;
+
+	res = __nvme_fc_init_request(ctrl, queue, &op->op, rq, queue->rqcnt++);
+	if (res)
+		return res;
+	op->op.fcp_req.first_sgl = op->sgl;
+	op->op.fcp_req.private = &op->priv[0];
+	nvme_req(rq)->ctrl = &ctrl->ctrl;
+	nvme_req(rq)->cmd = &op->op.cmd_iu.sqe;
+	return res;
+}
+
+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 = NULL;
+	int i, ret;
+
+	aen_op = ctrl->aen_ops;
+	for (i = 0; i < NVME_NR_AEN_COMMANDS; i++, aen_op++) {
+		if (ctrl->lport->ops->fcprqst_priv_sz) {
+			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.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++) {
+		__nvme_fc_exit_request(ctrl, aen_op);
+
+		kfree(aen_op->fcp_req.private);
+		aen_op->fcp_req.private = NULL;
+	}
+}
+
+static inline int
+__nvme_fc_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, unsigned int qidx)
+{
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(data);
+	struct nvme_fc_queue *queue = &ctrl->queues[qidx];
+
+	hctx->driver_data = queue;
+	queue->hctx = hctx;
+	return 0;
+}
+
+static int
+nvme_fc_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, unsigned int hctx_idx)
+{
+	return __nvme_fc_init_hctx(hctx, data, hctx_idx + 1);
+}
+
+static int
+nvme_fc_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	return __nvme_fc_init_hctx(hctx, data, hctx_idx);
+}
+
+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)
+		nvme_remove_io_tag_set(&ctrl->ctrl);
+
+	/* remove from rport list */
+	spin_lock_irqsave(&ctrl->rport->lock, flags);
+	list_del(&ctrl->ctrl_list);
+	spin_unlock_irqrestore(&ctrl->rport->lock, flags);
+
+	nvme_start_admin_queue(&ctrl->ctrl);
+	nvme_remove_admin_tag_set(&ctrl->ctrl);
+
+	kfree(ctrl->queues);
+
+	put_device(ctrl->dev);
+	nvme_fc_rport_put(ctrl->rport);
+
+	ida_free(&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);
+}
+
+/*
+ * 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 bool nvme_fc_terminate_exchange(struct request *req, void *data)
+{
+	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);
+
+	op->nreq.flags |= NVME_REQ_CANCELLED;
+	__nvme_fc_abort_op(ctrl, op);
+	return true;
+}
+
+/*
+ * This routine runs through all outstanding commands on the association
+ * and aborts them.  This routine is typically be called by the
+ * delete_association routine. It is also called due to an error during
+ * reconnect. In that scenario, it is most likely a command that initializes
+ * the controller, including fabric Connect commands on io queues, that
+ * may have timed out or failed thus the io must be killed for the connect
+ * thread to see the error.
+ */
+static void
+__nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
+{
+	int q;
+
+	/*
+	 * if aborting io, the queues are no longer good, mark them
+	 * all as not live.
+	 */
+	if (ctrl->ctrl.queue_count > 1) {
+		for (q = 1; q < ctrl->ctrl.queue_count; q++)
+			clear_bit(NVME_FC_Q_LIVE, &ctrl->queues[q].flags);
+	}
+	clear_bit(NVME_FC_Q_LIVE, &ctrl->queues[0].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);
+		nvme_sync_io_queues(&ctrl->ctrl);
+		blk_mq_tagset_busy_iter(&ctrl->tag_set,
+				nvme_fc_terminate_exchange, &ctrl->ctrl);
+		blk_mq_tagset_wait_completed_request(&ctrl->tag_set);
+		if (start_queues)
+			nvme_start_queues(&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.
+	 */
+	nvme_stop_admin_queue(&ctrl->ctrl);
+	blk_sync_queue(ctrl->ctrl.admin_q);
+	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
+				nvme_fc_terminate_exchange, &ctrl->ctrl);
+	blk_mq_tagset_wait_completed_request(&ctrl->admin_tag_set);
+	if (start_queues)
+		nvme_start_admin_queue(&ctrl->ctrl);
+}
+
+static void
+nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
+{
+	/*
+	 * if an error (io timeout, etc) while (re)connecting, the remote
+	 * port requested terminating of the association (disconnect_ls)
+	 * or an error (timeout or abort) occurred on an io while creating
+	 * the controller.  Abort any ios on the association and let the
+	 * create_association error path resolve things.
+	 */
+	if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {
+		__nvme_fc_abort_outstanding_ios(ctrl, true);
+		set_bit(ASSOC_FAILED, &ctrl->flags);
+		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 event: %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)
+{
+	struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
+	struct nvme_fc_ctrl *ctrl = op->ctrl;
+	struct nvme_fc_cmd_iu *cmdiu = &op->cmd_iu;
+	struct nvme_command *sqe = &cmdiu->sqe;
+
+	/*
+	 * Attempt to abort the offending command. Command completion
+	 * will detect the aborted io and will fail the connection.
+	 */
+	dev_info(ctrl->ctrl.device,
+		"NVME-FC{%d.%d}: io timeout: opcode %d fctype %d w10/11: "
+		"x%08x/x%08x\n",
+		ctrl->cnum, op->queue->qnum, sqe->common.opcode,
+		sqe->connect.fctype, sqe->common.cdw10, sqe->common.cdw11);
+	if (__nvme_fc_abort_op(ctrl, op))
+		nvme_fc_error_recovery(ctrl, "io timeout abort failed");
+
+	/*
+	 * 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;
+	int ret;
+
+	freq->sg_cnt = 0;
+
+	if (!blk_rq_nr_phys_segments(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,
+			NVME_INLINE_SG_CNT);
+	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));
+	freq->sg_cnt = fc_dma_map_sg(ctrl->lport->dev, freq->sg_table.sgl,
+				op->nents, rq_dma_dir(rq));
+	if (unlikely(freq->sg_cnt <= 0)) {
+		sg_free_table_chained(&freq->sg_table, NVME_INLINE_SG_CNT);
+		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_dma_dir(rq));
+
+	sg_free_table_chained(&freq->sg_table, NVME_INLINE_SG_CNT);
+
+	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_cleanup_cmd(op->rq);
+		}
+
+		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);
+	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 ||
+	    !nvme_check_ready(&queue->ctrl->ctrl, rq, queue_ready))
+		return nvme_fail_nonready_command(&queue->ctrl->ctrl, rq);
+
+	ret = nvme_setup_cmd(ns, rq);
+	if (ret)
+		return ret;
+
+	/*
+	 * nvme core doesn't quite treat the rq opaquely. Commands such
+	 * as WRITE ZEROES will return a non-zero rq payload_bytes yet
+	 * there is no actual payload to be transferred.
+	 * To get it right, key data transmission on there being 1 or
+	 * more physical segments in the sg list. If there is no
+	 * physical segments, there is no payload.
+	 */
+	if (blk_rq_nr_phys_segments(rq)) {
+		data_len = blk_rq_payload_bytes(rq);
+		io_dir = ((rq_data_dir(rq) == WRITE) ?
+					NVMEFC_FCP_WRITE : NVMEFC_FCP_READ);
+	} else {
+		data_len = 0;
+		io_dir = NVMEFC_FCP_NODATA;
+	}
+
+
+	return nvme_fc_start_fcp_op(ctrl, queue, op, data_len, io_dir);
+}
+
+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;
+	blk_status_t ret;
+
+	if (test_bit(FCCTRL_TERMIO, &ctrl->flags))
+		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);
+	op->flags &= ~FCOP_FLAGS_TERMIO;
+
+	nvme_fc_unmap_data(ctrl, rq, op);
+	nvme_complete_rq(rq);
+	nvme_fc_ctrl_put(ctrl);
+}
+
+static void nvme_fc_map_queues(struct blk_mq_tag_set *set)
+{
+	struct nvme_fc_ctrl *ctrl = to_fc_ctrl(set->driver_data);
+	int i;
+
+	for (i = 0; i < set->nr_maps; i++) {
+		struct blk_mq_queue_map *map = &set->map[i];
+
+		if (!map->nr_queues) {
+			WARN_ON(i == HCTX_TYPE_DEFAULT);
+			continue;
+		}
+
+		/* Call LLDD map queue functionality if defined */
+		if (ctrl->lport->ops->map_queues)
+			ctrl->lport->ops->map_queues(&ctrl->lport->localport,
+						     map);
+		else
+			blk_mq_map_queues(map);
+	}
+}
+
+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,
+	.timeout	= nvme_fc_timeout,
+	.map_queues	= nvme_fc_map_queues,
+};
+
+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);
+
+	ret = nvme_alloc_io_tag_set(&ctrl->ctrl, &ctrl->tag_set,
+			&nvme_fc_mq_ops, 1,
+			struct_size((struct nvme_fcp_op_w_sgl *)NULL, priv,
+				    ctrl->lport->ops->fcprqst_priv_sz));
+	if (ret)
+		return ret;
+
+	ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
+	if (ret)
+		goto out_cleanup_tagset;
+
+	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_tagset:
+	nvme_remove_io_tag_set(&ctrl->ctrl);
+	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;
+	u32 prior_ioq_cnt = ctrl->ctrl.queue_count - 1;
+	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;
+	}
+
+	if (!nr_io_queues && prior_ioq_cnt) {
+		dev_info(ctrl->ctrl.device,
+			"Fail Reconnect: At least 1 io queue "
+			"required (was %d)\n", prior_ioq_cnt);
+		return -ENOSPC;
+	}
+
+	ctrl->ctrl.queue_count = nr_io_queues + 1;
+	/* check for io queues existing */
+	if (ctrl->ctrl.queue_count == 1)
+		return 0;
+
+	if (prior_ioq_cnt != nr_io_queues) {
+		dev_info(ctrl->ctrl.device,
+			"reconnect: revising io queue count from %d to %d\n",
+			prior_ioq_cnt, nr_io_queues);
+		blk_mq_update_nr_hw_queues(&ctrl->tag_set, nr_io_queues);
+	}
+
+	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;
+
+	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 (test_and_set_bit(ASSOC_ACTIVE, &ctrl->flags))
+		return 1;
+
+	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;
+
+	/* clearing of ctrl->flags ASSOC_ACTIVE bit is in association delete */
+
+	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;
+	struct nvmefc_ls_rcv_op *disls = NULL;
+	unsigned long flags;
+	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;
+
+	dev_info(ctrl->ctrl.device,
+		"NVME-FC{%d}: create association : host wwpn 0x%016llx "
+		" rport wwpn 0x%016llx: NQN \"%s\"\n",
+		ctrl->cnum, ctrl->lport->localport.port_name,
+		ctrl->rport->remoteport.port_name, ctrl->ctrl.opts->subsysnqn);
+
+	clear_bit(ASSOC_FAILED, &ctrl->flags);
+
+	/*
+	 * 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;
+
+	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 = nvme_enable_ctrl(&ctrl->ctrl);
+	if (ret || test_bit(ASSOC_FAILED, &ctrl->flags))
+		goto out_disconnect_admin_queue;
+
+	ctrl->ctrl.max_segments = ctrl->lport->ops->max_sgl_segments;
+	ctrl->ctrl.max_hw_sectors = ctrl->ctrl.max_segments <<
+						(ilog2(SZ_4K) - 9);
+
+	nvme_start_admin_queue(&ctrl->ctrl);
+
+	ret = nvme_init_ctrl_finish(&ctrl->ctrl);
+	if (ret || test_bit(ASSOC_FAILED, &ctrl->flags))
+		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);
+		ret = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
+		goto out_disconnect_admin_queue;
+	}
+
+	/* FC-NVME supports normal SGL Data Block Descriptors */
+	if (!nvme_ctrl_sgl_supported(&ctrl->ctrl)) {
+		dev_err(ctrl->ctrl.device,
+			"Mandatory sgls are not supported!\n");
+		ret = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
+		goto out_disconnect_admin_queue;
+	}
+
+	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 maxcmd\n",
+			opts->queue_size, ctrl->ctrl.maxcmd);
+		opts->queue_size = ctrl->ctrl.maxcmd;
+		ctrl->ctrl.sqsize = opts->queue_size - 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 || test_bit(ASSOC_FAILED, &ctrl->flags))
+		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);
+	spin_lock_irqsave(&ctrl->lock, flags);
+	ctrl->association_id = 0;
+	disls = ctrl->rcv_disconn;
+	ctrl->rcv_disconn = NULL;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+	if (disls)
+		nvme_fc_xmt_ls_rsp(disls);
+out_delete_hw_queue:
+	__nvme_fc_delete_hw_queue(ctrl, &ctrl->queues[0], 0);
+out_free_queue:
+	nvme_fc_free_queue(&ctrl->queues[0]);
+	clear_bit(ASSOC_ACTIVE, &ctrl->flags);
+	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)
+{
+	struct nvmefc_ls_rcv_op *disls = NULL;
+	unsigned long flags;
+
+	if (!test_and_clear_bit(ASSOC_ACTIVE, &ctrl->flags))
+		return;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	set_bit(FCCTRL_TERMIO, &ctrl->flags);
+	ctrl->iocnt = 0;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+
+	__nvme_fc_abort_outstanding_ios(ctrl, false);
+
+	/* 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);
+	clear_bit(FCCTRL_TERMIO, &ctrl->flags);
+	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);
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	ctrl->association_id = 0;
+	disls = ctrl->rcv_disconn;
+	ctrl->rcv_disconn = NULL;
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+	if (disls)
+		/*
+		 * if a Disconnect Request was waiting for a response, send
+		 * now that all ABTS's have been issued (and are complete).
+		 */
+		nvme_fc_xmt_ls_rsp(disls);
+
+	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 */
+	nvme_start_admin_queue(&ctrl->ctrl);
+
+	/* 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->ioerr_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);
+		if (status > 0 && (status & NVME_SC_DNR))
+			recon = false;
+	} 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) {
+			if (status > 0 && (status & NVME_SC_DNR))
+				dev_warn(ctrl->ctrl.device,
+					 "NVME-FC{%d}: reconnect failure\n",
+					 ctrl->cnum);
+			else
+				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, min_t(int, portptr->dev_loss_tmo,
+					(ctrl->ctrl.opts->max_reconnects *
+					 ctrl->ctrl.opts->reconnect_delay)));
+		WARN_ON(nvme_delete_ctrl(&ctrl->ctrl));
+	}
+}
+
+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);
+
+	nvme_stop_ctrl(&ctrl->ctrl);
+
+	/* will block will waiting for io to terminate */
+	nvme_fc_delete_association(ctrl);
+
+	if (!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);
+
+	if (ctrl->rport->remoteport.port_state == FC_OBJSTATE_ONLINE) {
+		if (!queue_delayed_work(nvme_wq, &ctrl->connect_work, 0)) {
+			dev_err(ctrl->ctrl.device,
+				"NVME-FC{%d}: failed to schedule connect "
+				"after reset\n", ctrl->cnum);
+		} else {
+			flush_delayed_work(&ctrl->connect_work);
+		}
+	} else {
+		nvme_fc_reconnect_or_delete(ctrl, -ENOTCONN);
+	}
+}
+
+
+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, ctrl_loss_tmo;
+
+	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_alloc(&nvme_fc_ctrl_cnt, GFP_KERNEL);
+	if (idx < 0) {
+		ret = -ENOSPC;
+		goto out_free_ctrl;
+	}
+
+	/*
+	 * if ctrl_loss_tmo is being enforced and the default reconnect delay
+	 * is being used, change to a shorter reconnect delay for FC.
+	 */
+	if (opts->max_reconnects != -1 &&
+	    opts->reconnect_delay == NVMF_DEF_RECONNECT_DELAY &&
+	    opts->reconnect_delay > NVME_FC_DEFAULT_RECONNECT_TMO) {
+		ctrl_loss_tmo = opts->max_reconnects * opts->reconnect_delay;
+		opts->reconnect_delay = NVME_FC_DEFAULT_RECONNECT_TMO;
+		opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
+						opts->reconnect_delay);
+	}
+
+	ctrl->ctrl.opts = opts;
+	ctrl->ctrl.nr_reconnects = 0;
+	if (lport->dev)
+		ctrl->ctrl.numa_node = dev_to_node(lport->dev);
+	else
+		ctrl->ctrl.numa_node = NUMA_NO_NODE;
+	INIT_LIST_HEAD(&ctrl->ctrl_list);
+	ctrl->lport = lport;
+	ctrl->rport = rport;
+	ctrl->dev = lport->dev;
+	ctrl->cnum = idx;
+	ctrl->ioq_live = false;
+	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->ioerr_work, nvme_fc_ctrl_ioerr_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);
+
+	/*
+	 * 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_free_queues;
+
+	/* at this point, teardown path changes to ref counting on nvme ctrl */
+
+	ret = nvme_alloc_admin_tag_set(&ctrl->ctrl, &ctrl->admin_tag_set,
+			&nvme_fc_admin_mq_ops,
+			struct_size((struct nvme_fcp_op_w_sgl *)NULL, priv,
+				    ctrl->lport->ops->fcprqst_priv_sz));
+	if (ret)
+		goto fail_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;
+	}
+
+	if (!queue_delayed_work(nvme_wq, &ctrl->connect_work, 0)) {
+		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, nvmf_ctrl_subsysnqn(&ctrl->ctrl));
+
+	return &ctrl->ctrl;
+
+fail_ctrl:
+	nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING);
+	cancel_work_sync(&ctrl->ioerr_work);
+	cancel_work_sync(&ctrl->ctrl.reset_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_free_queues:
+	kfree(ctrl->queues);
+out_free_ida:
+	put_device(ctrl->dev);
+	ida_free(&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 if string is 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,
+};
+
+/* Arbitrary successive failures max. With lots of subsystems could be high */
+#define DISCOVERY_MAX_FAIL	20
+
+static ssize_t nvme_fc_nvme_discovery_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	unsigned long flags;
+	LIST_HEAD(local_disc_list);
+	struct nvme_fc_lport *lport;
+	struct nvme_fc_rport *rport;
+	int failcnt = 0;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+restart:
+	list_for_each_entry(lport, &nvme_fc_lport_list, port_list) {
+		list_for_each_entry(rport, &lport->endp_list, endp_list) {
+			if (!nvme_fc_lport_get(lport))
+				continue;
+			if (!nvme_fc_rport_get(rport)) {
+				/*
+				 * This is a temporary condition. Upon restart
+				 * this rport will be gone from the list.
+				 *
+				 * Revert the lport put and retry.  Anything
+				 * added to the list already will be skipped (as
+				 * they are no longer list_empty).  Loops should
+				 * resume at rports that were not yet seen.
+				 */
+				nvme_fc_lport_put(lport);
+
+				if (failcnt++ < DISCOVERY_MAX_FAIL)
+					goto restart;
+
+				pr_err("nvme_discovery: too many reference "
+				       "failures\n");
+				goto process_local_list;
+			}
+			if (list_empty(&rport->disc_list))
+				list_add_tail(&rport->disc_list,
+					      &local_disc_list);
+		}
+	}
+
+process_local_list:
+	while (!list_empty(&local_disc_list)) {
+		rport = list_first_entry(&local_disc_list,
+					 struct nvme_fc_rport, disc_list);
+		list_del_init(&rport->disc_list);
+		spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+		lport = rport->lport;
+		/* signal discovery. Won't hurt if it repeats */
+		nvme_fc_signal_discovery_scan(lport, rport);
+		nvme_fc_rport_put(rport);
+		nvme_fc_lport_put(lport);
+
+		spin_lock_irqsave(&nvme_fc_lock, flags);
+	}
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+
+	return count;
+}
+
+static DEVICE_ATTR(nvme_discovery, 0200, NULL, nvme_fc_nvme_discovery_store);
+
+#ifdef CONFIG_BLK_CGROUP_FC_APPID
+/* Parse the cgroup id from a buf and return the length of cgrpid */
+static int fc_parse_cgrpid(const char *buf, u64 *id)
+{
+	char cgrp_id[16+1];
+	int cgrpid_len, j;
+
+	memset(cgrp_id, 0x0, sizeof(cgrp_id));
+	for (cgrpid_len = 0, j = 0; cgrpid_len < 17; cgrpid_len++) {
+		if (buf[cgrpid_len] != ':')
+			cgrp_id[cgrpid_len] = buf[cgrpid_len];
+		else {
+			j = 1;
+			break;
+		}
+	}
+	if (!j)
+		return -EINVAL;
+	if (kstrtou64(cgrp_id, 16, id) < 0)
+		return -EINVAL;
+	return cgrpid_len;
+}
+
+/*
+ * Parse and update the appid in the blkcg associated with the cgroupid.
+ */
+static ssize_t fc_appid_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	size_t orig_count = count;
+	u64 cgrp_id;
+	int appid_len = 0;
+	int cgrpid_len = 0;
+	char app_id[FC_APPID_LEN];
+	int ret = 0;
+
+	if (buf[count-1] == '\n')
+		count--;
+
+	if ((count > (16+1+FC_APPID_LEN)) || (!strchr(buf, ':')))
+		return -EINVAL;
+
+	cgrpid_len = fc_parse_cgrpid(buf, &cgrp_id);
+	if (cgrpid_len < 0)
+		return -EINVAL;
+	appid_len = count - cgrpid_len - 1;
+	if (appid_len > FC_APPID_LEN)
+		return -EINVAL;
+
+	memset(app_id, 0x0, sizeof(app_id));
+	memcpy(app_id, &buf[cgrpid_len+1], appid_len);
+	ret = blkcg_set_fc_appid(app_id, cgrp_id, sizeof(app_id));
+	if (ret < 0)
+		return ret;
+	return orig_count;
+}
+static DEVICE_ATTR(appid_store, 0200, NULL, fc_appid_store);
+#endif /* CONFIG_BLK_CGROUP_FC_APPID */
+
+static struct attribute *nvme_fc_attrs[] = {
+	&dev_attr_nvme_discovery.attr,
+#ifdef CONFIG_BLK_CGROUP_FC_APPID
+	&dev_attr_appid_store.attr,
+#endif
+	NULL
+};
+
+static const struct attribute_group nvme_fc_attr_group = {
+	.attrs = nvme_fc_attrs,
+};
+
+static const struct attribute_group *nvme_fc_attr_groups[] = {
+	&nvme_fc_attr_group,
+	NULL
+};
+
+static struct class fc_class = {
+	.name = "fc",
+	.dev_groups = nvme_fc_attr_groups,
+	.owner = THIS_MODULE,
+};
+
+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.
+	 */
+	ret = class_register(&fc_class);
+	if (ret) {
+		pr_err("couldn't register class fc\n");
+		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_unregister(&fc_class);
+out_destroy_wq:
+	destroy_workqueue(nvme_fc_wq);
+
+	return ret;
+}
+
+static void
+nvme_fc_delete_controllers(struct nvme_fc_rport *rport)
+{
+	struct nvme_fc_ctrl *ctrl;
+
+	spin_lock(&rport->lock);
+	list_for_each_entry(ctrl, &rport->ctrl_list, ctrl_list) {
+		dev_warn(ctrl->ctrl.device,
+			"NVME-FC{%d}: transport unloading: deleting ctrl\n",
+			ctrl->cnum);
+		nvme_delete_ctrl(&ctrl->ctrl);
+	}
+	spin_unlock(&rport->lock);
+}
+
+static void
+nvme_fc_cleanup_for_unload(void)
+{
+	struct nvme_fc_lport *lport;
+	struct nvme_fc_rport *rport;
+
+	list_for_each_entry(lport, &nvme_fc_lport_list, port_list) {
+		list_for_each_entry(rport, &lport->endp_list, endp_list) {
+			nvme_fc_delete_controllers(rport);
+		}
+	}
+}
+
+static void __exit nvme_fc_exit_module(void)
+{
+	unsigned long flags;
+	bool need_cleanup = false;
+
+	spin_lock_irqsave(&nvme_fc_lock, flags);
+	nvme_fc_waiting_to_unload = true;
+	if (!list_empty(&nvme_fc_lport_list)) {
+		need_cleanup = true;
+		nvme_fc_cleanup_for_unload();
+	}
+	spin_unlock_irqrestore(&nvme_fc_lock, flags);
+	if (need_cleanup) {
+		pr_info("%s: waiting for ctlr deletes\n", __func__);
+		wait_for_completion(&nvme_fc_unload_proceed);
+		pr_info("%s: ctrl deletes complete\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_unregister(&fc_class);
+	destroy_workqueue(nvme_fc_wq);
+}
+
+module_init(nvme_fc_init_module);
+module_exit(nvme_fc_exit_module);
+
+MODULE_LICENSE("GPL v2");