Adding upstream version 5.10.209.upstream/5.10.209

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

1 files changed, 2936 insertions, 0 deletions

diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
new file mode 100644
index 000000000..46fc44ce8
--- /dev/null
+++ b/drivers/nvme/target/fc.c
@@ -0,0 +1,2936 @@
+// 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/slab.h>
+#include <linux/blk-mq.h>
+#include <linux/parser.h>
+#include <linux/random.h>
+#include <uapi/scsi/fc/fc_fs.h>
+#include <uapi/scsi/fc/fc_els.h>
+
+#include "nvmet.h"
+#include <linux/nvme-fc-driver.h>
+#include <linux/nvme-fc.h>
+#include "../host/fc.h"
+
+
+/* *************************** Data Structures/Defines ****************** */
+
+
+#define NVMET_LS_CTX_COUNT		256
+
+struct nvmet_fc_tgtport;
+struct nvmet_fc_tgt_assoc;
+
+struct nvmet_fc_ls_iod {		/* for an LS RQST RCV */
+	struct nvmefc_ls_rsp		*lsrsp;
+	struct nvmefc_tgt_fcp_req	*fcpreq;	/* only if RS */
+
+	struct list_head		ls_rcv_list; /* tgtport->ls_rcv_list */
+
+	struct nvmet_fc_tgtport		*tgtport;
+	struct nvmet_fc_tgt_assoc	*assoc;
+	void				*hosthandle;
+
+	union nvmefc_ls_requests	*rqstbuf;
+	union nvmefc_ls_responses	*rspbuf;
+	u16				rqstdatalen;
+	dma_addr_t			rspdma;
+
+	struct scatterlist		sg[2];
+
+	struct work_struct		work;
+} __aligned(sizeof(unsigned long long));
+
+struct nvmet_fc_ls_req_op {		/* for an LS RQST XMT */
+	struct nvmefc_ls_req		ls_req;
+
+	struct nvmet_fc_tgtport		*tgtport;
+	void				*hosthandle;
+
+	int				ls_error;
+	struct list_head		lsreq_list; /* tgtport->ls_req_list */
+	bool				req_queued;
+};
+
+
+/* desired maximum for a single sequence - if sg list allows it */
+#define NVMET_FC_MAX_SEQ_LENGTH		(256 * 1024)
+
+enum nvmet_fcp_datadir {
+	NVMET_FCP_NODATA,
+	NVMET_FCP_WRITE,
+	NVMET_FCP_READ,
+	NVMET_FCP_ABORTED,
+};
+
+struct nvmet_fc_fcp_iod {
+	struct nvmefc_tgt_fcp_req	*fcpreq;
+
+	struct nvme_fc_cmd_iu		cmdiubuf;
+	struct nvme_fc_ersp_iu		rspiubuf;
+	dma_addr_t			rspdma;
+	struct scatterlist		*next_sg;
+	struct scatterlist		*data_sg;
+	int				data_sg_cnt;
+	u32				offset;
+	enum nvmet_fcp_datadir		io_dir;
+	bool				active;
+	bool				abort;
+	bool				aborted;
+	bool				writedataactive;
+	spinlock_t			flock;
+
+	struct nvmet_req		req;
+	struct work_struct		defer_work;
+
+	struct nvmet_fc_tgtport		*tgtport;
+	struct nvmet_fc_tgt_queue	*queue;
+
+	struct list_head		fcp_list;	/* tgtport->fcp_list */
+};
+
+struct nvmet_fc_tgtport {
+	struct nvmet_fc_target_port	fc_target_port;
+
+	struct list_head		tgt_list; /* nvmet_fc_target_list */
+	struct device			*dev;	/* dev for dma mapping */
+	struct nvmet_fc_target_template	*ops;
+
+	struct nvmet_fc_ls_iod		*iod;
+	spinlock_t			lock;
+	struct list_head		ls_rcv_list;
+	struct list_head		ls_req_list;
+	struct list_head		ls_busylist;
+	struct list_head		assoc_list;
+	struct list_head		host_list;
+	struct ida			assoc_cnt;
+	struct nvmet_fc_port_entry	*pe;
+	struct kref			ref;
+	u32				max_sg_cnt;
+};
+
+struct nvmet_fc_port_entry {
+	struct nvmet_fc_tgtport		*tgtport;
+	struct nvmet_port		*port;
+	u64				node_name;
+	u64				port_name;
+	struct list_head		pe_list;
+};
+
+struct nvmet_fc_defer_fcp_req {
+	struct list_head		req_list;
+	struct nvmefc_tgt_fcp_req	*fcp_req;
+};
+
+struct nvmet_fc_tgt_queue {
+	bool				ninetypercent;
+	u16				qid;
+	u16				sqsize;
+	u16				ersp_ratio;
+	__le16				sqhd;
+	atomic_t			connected;
+	atomic_t			sqtail;
+	atomic_t			zrspcnt;
+	atomic_t			rsn;
+	spinlock_t			qlock;
+	struct nvmet_cq			nvme_cq;
+	struct nvmet_sq			nvme_sq;
+	struct nvmet_fc_tgt_assoc	*assoc;
+	struct list_head		fod_list;
+	struct list_head		pending_cmd_list;
+	struct list_head		avail_defer_list;
+	struct workqueue_struct		*work_q;
+	struct kref			ref;
+	struct nvmet_fc_fcp_iod		fod[];		/* array of fcp_iods */
+} __aligned(sizeof(unsigned long long));
+
+struct nvmet_fc_hostport {
+	struct nvmet_fc_tgtport		*tgtport;
+	void				*hosthandle;
+	struct list_head		host_list;
+	struct kref			ref;
+	u8				invalid;
+};
+
+struct nvmet_fc_tgt_assoc {
+	u64				association_id;
+	u32				a_id;
+	atomic_t			terminating;
+	struct nvmet_fc_tgtport		*tgtport;
+	struct nvmet_fc_hostport	*hostport;
+	struct nvmet_fc_ls_iod		*rcv_disconn;
+	struct list_head		a_list;
+	struct nvmet_fc_tgt_queue	*queues[NVMET_NR_QUEUES + 1];
+	struct kref			ref;
+	struct work_struct		del_work;
+};
+
+
+static inline int
+nvmet_fc_iodnum(struct nvmet_fc_ls_iod *iodptr)
+{
+	return (iodptr - iodptr->tgtport->iod);
+}
+
+static inline int
+nvmet_fc_fodnum(struct nvmet_fc_fcp_iod *fodptr)
+{
+	return (fodptr - fodptr->queue->fod);
+}
+
+
+/*
+ * Association and Connection IDs:
+ *
+ * Association ID will have random number in upper 6 bytes and zero
+ *   in lower 2 bytes
+ *
+ * Connection IDs will be Association ID with QID or'd in lower 2 bytes
+ *
+ * note: Association ID = Connection ID for queue 0
+ */
+#define BYTES_FOR_QID			sizeof(u16)
+#define BYTES_FOR_QID_SHIFT		(BYTES_FOR_QID * 8)
+#define NVMET_FC_QUEUEID_MASK		((u64)((1 << BYTES_FOR_QID_SHIFT) - 1))
+
+static inline u64
+nvmet_fc_makeconnid(struct nvmet_fc_tgt_assoc *assoc, u16 qid)
+{
+	return (assoc->association_id | qid);
+}
+
+static inline u64
+nvmet_fc_getassociationid(u64 connectionid)
+{
+	return connectionid & ~NVMET_FC_QUEUEID_MASK;
+}
+
+static inline u16
+nvmet_fc_getqueueid(u64 connectionid)
+{
+	return (u16)(connectionid & NVMET_FC_QUEUEID_MASK);
+}
+
+static inline struct nvmet_fc_tgtport *
+targetport_to_tgtport(struct nvmet_fc_target_port *targetport)
+{
+	return container_of(targetport, struct nvmet_fc_tgtport,
+				 fc_target_port);
+}
+
+static inline struct nvmet_fc_fcp_iod *
+nvmet_req_to_fod(struct nvmet_req *nvme_req)
+{
+	return container_of(nvme_req, struct nvmet_fc_fcp_iod, req);
+}
+
+
+/* *************************** Globals **************************** */
+
+
+static DEFINE_SPINLOCK(nvmet_fc_tgtlock);
+
+static LIST_HEAD(nvmet_fc_target_list);
+static DEFINE_IDA(nvmet_fc_tgtport_cnt);
+static LIST_HEAD(nvmet_fc_portentry_list);
+
+
+static void nvmet_fc_handle_ls_rqst_work(struct work_struct *work);
+static void nvmet_fc_fcp_rqst_op_defer_work(struct work_struct *work);
+static void nvmet_fc_tgt_a_put(struct nvmet_fc_tgt_assoc *assoc);
+static int nvmet_fc_tgt_a_get(struct nvmet_fc_tgt_assoc *assoc);
+static void nvmet_fc_tgt_q_put(struct nvmet_fc_tgt_queue *queue);
+static int nvmet_fc_tgt_q_get(struct nvmet_fc_tgt_queue *queue);
+static void nvmet_fc_tgtport_put(struct nvmet_fc_tgtport *tgtport);
+static int nvmet_fc_tgtport_get(struct nvmet_fc_tgtport *tgtport);
+static void nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
+					struct nvmet_fc_fcp_iod *fod);
+static void nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc);
+static void nvmet_fc_xmt_ls_rsp(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_ls_iod *iod);
+
+
+/* *********************** 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 XMT Handling ************************* */
+
+
+static void
+__nvmet_fc_finish_ls_req(struct nvmet_fc_ls_req_op *lsop)
+{
+	struct nvmet_fc_tgtport *tgtport = lsop->tgtport;
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+
+	if (!lsop->req_queued) {
+		spin_unlock_irqrestore(&tgtport->lock, flags);
+		return;
+	}
+
+	list_del(&lsop->lsreq_list);
+
+	lsop->req_queued = false;
+
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+
+	nvmet_fc_tgtport_put(tgtport);
+}
+
+static int
+__nvmet_fc_send_ls_req(struct nvmet_fc_tgtport *tgtport,
+		struct nvmet_fc_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 (!tgtport->ops->ls_req)
+		return -EOPNOTSUPP;
+
+	if (!nvmet_fc_tgtport_get(tgtport))
+		return -ESHUTDOWN;
+
+	lsreq->done = done;
+	lsop->req_queued = false;
+	INIT_LIST_HEAD(&lsop->lsreq_list);
+
+	lsreq->rqstdma = fc_dma_map_single(tgtport->dev, lsreq->rqstaddr,
+				  lsreq->rqstlen + lsreq->rsplen,
+				  DMA_BIDIRECTIONAL);
+	if (fc_dma_mapping_error(tgtport->dev, lsreq->rqstdma)) {
+		ret = -EFAULT;
+		goto out_puttgtport;
+	}
+	lsreq->rspdma = lsreq->rqstdma + lsreq->rqstlen;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+
+	list_add_tail(&lsop->lsreq_list, &tgtport->ls_req_list);
+
+	lsop->req_queued = true;
+
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	ret = tgtport->ops->ls_req(&tgtport->fc_target_port, lsop->hosthandle,
+				   lsreq);
+	if (ret)
+		goto out_unlink;
+
+	return 0;
+
+out_unlink:
+	lsop->ls_error = ret;
+	spin_lock_irqsave(&tgtport->lock, flags);
+	lsop->req_queued = false;
+	list_del(&lsop->lsreq_list);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+out_puttgtport:
+	nvmet_fc_tgtport_put(tgtport);
+
+	return ret;
+}
+
+static int
+nvmet_fc_send_ls_req_async(struct nvmet_fc_tgtport *tgtport,
+		struct nvmet_fc_ls_req_op *lsop,
+		void (*done)(struct nvmefc_ls_req *req, int status))
+{
+	/* don't wait for completion */
+
+	return __nvmet_fc_send_ls_req(tgtport, lsop, done);
+}
+
+static void
+nvmet_fc_disconnect_assoc_done(struct nvmefc_ls_req *lsreq, int status)
+{
+	struct nvmet_fc_ls_req_op *lsop =
+		container_of(lsreq, struct nvmet_fc_ls_req_op, ls_req);
+
+	__nvmet_fc_finish_ls_req(lsop);
+
+	/* fc-nvme target 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 target 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 host, so the target may never get a
+ * response even if it 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 host
+ * is present and receives the LS, it too can tear down.
+ */
+static void
+nvmet_fc_xmt_disconnect_assoc(struct nvmet_fc_tgt_assoc *assoc)
+{
+	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
+	struct fcnvme_ls_disconnect_assoc_rqst *discon_rqst;
+	struct fcnvme_ls_disconnect_assoc_acc *discon_acc;
+	struct nvmet_fc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	int ret;
+
+	/*
+	 * If ls_req is NULL or no hosthandle, it's an older lldd and no
+	 * message is normal. Otherwise, send unless the hostport has
+	 * already been invalidated by the lldd.
+	 */
+	if (!tgtport->ops->ls_req || !assoc->hostport ||
+	    assoc->hostport->invalid)
+		return;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			sizeof(*discon_rqst) + sizeof(*discon_acc) +
+			tgtport->ops->lsrqst_priv_sz), GFP_KERNEL);
+	if (!lsop) {
+		dev_info(tgtport->dev,
+			"{%d:%d} send Disconnect Association failed: ENOMEM\n",
+			tgtport->fc_target_port.port_num, assoc->a_id);
+		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 (tgtport->ops->lsrqst_priv_sz)
+		lsreq->private = (void *)&discon_acc[1];
+	else
+		lsreq->private = NULL;
+
+	lsop->tgtport = tgtport;
+	lsop->hosthandle = assoc->hostport->hosthandle;
+
+	nvmefc_fmt_lsreq_discon_assoc(lsreq, discon_rqst, discon_acc,
+				assoc->association_id);
+
+	ret = nvmet_fc_send_ls_req_async(tgtport, lsop,
+				nvmet_fc_disconnect_assoc_done);
+	if (ret) {
+		dev_info(tgtport->dev,
+			"{%d:%d} XMT Disconnect Association failed: %d\n",
+			tgtport->fc_target_port.port_num, assoc->a_id, ret);
+		kfree(lsop);
+	}
+}
+
+
+/* *********************** FC-NVME Port Management ************************ */
+
+
+static int
+nvmet_fc_alloc_ls_iodlist(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_ls_iod *iod;
+	int i;
+
+	iod = kcalloc(NVMET_LS_CTX_COUNT, sizeof(struct nvmet_fc_ls_iod),
+			GFP_KERNEL);
+	if (!iod)
+		return -ENOMEM;
+
+	tgtport->iod = iod;
+
+	for (i = 0; i < NVMET_LS_CTX_COUNT; iod++, i++) {
+		INIT_WORK(&iod->work, nvmet_fc_handle_ls_rqst_work);
+		iod->tgtport = tgtport;
+		list_add_tail(&iod->ls_rcv_list, &tgtport->ls_rcv_list);
+
+		iod->rqstbuf = kzalloc(sizeof(union nvmefc_ls_requests) +
+				       sizeof(union nvmefc_ls_responses),
+				       GFP_KERNEL);
+		if (!iod->rqstbuf)
+			goto out_fail;
+
+		iod->rspbuf = (union nvmefc_ls_responses *)&iod->rqstbuf[1];
+
+		iod->rspdma = fc_dma_map_single(tgtport->dev, iod->rspbuf,
+						sizeof(*iod->rspbuf),
+						DMA_TO_DEVICE);
+		if (fc_dma_mapping_error(tgtport->dev, iod->rspdma))
+			goto out_fail;
+	}
+
+	return 0;
+
+out_fail:
+	kfree(iod->rqstbuf);
+	list_del(&iod->ls_rcv_list);
+	for (iod--, i--; i >= 0; iod--, i--) {
+		fc_dma_unmap_single(tgtport->dev, iod->rspdma,
+				sizeof(*iod->rspbuf), DMA_TO_DEVICE);
+		kfree(iod->rqstbuf);
+		list_del(&iod->ls_rcv_list);
+	}
+
+	kfree(iod);
+
+	return -EFAULT;
+}
+
+static void
+nvmet_fc_free_ls_iodlist(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_ls_iod *iod = tgtport->iod;
+	int i;
+
+	for (i = 0; i < NVMET_LS_CTX_COUNT; iod++, i++) {
+		fc_dma_unmap_single(tgtport->dev,
+				iod->rspdma, sizeof(*iod->rspbuf),
+				DMA_TO_DEVICE);
+		kfree(iod->rqstbuf);
+		list_del(&iod->ls_rcv_list);
+	}
+	kfree(tgtport->iod);
+}
+
+static struct nvmet_fc_ls_iod *
+nvmet_fc_alloc_ls_iod(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_ls_iod *iod;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	iod = list_first_entry_or_null(&tgtport->ls_rcv_list,
+					struct nvmet_fc_ls_iod, ls_rcv_list);
+	if (iod)
+		list_move_tail(&iod->ls_rcv_list, &tgtport->ls_busylist);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	return iod;
+}
+
+
+static void
+nvmet_fc_free_ls_iod(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_ls_iod *iod)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_move(&iod->ls_rcv_list, &tgtport->ls_rcv_list);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+}
+
+static void
+nvmet_fc_prep_fcp_iodlist(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_tgt_queue *queue)
+{
+	struct nvmet_fc_fcp_iod *fod = queue->fod;
+	int i;
+
+	for (i = 0; i < queue->sqsize; fod++, i++) {
+		INIT_WORK(&fod->defer_work, nvmet_fc_fcp_rqst_op_defer_work);
+		fod->tgtport = tgtport;
+		fod->queue = queue;
+		fod->active = false;
+		fod->abort = false;
+		fod->aborted = false;
+		fod->fcpreq = NULL;
+		list_add_tail(&fod->fcp_list, &queue->fod_list);
+		spin_lock_init(&fod->flock);
+
+		fod->rspdma = fc_dma_map_single(tgtport->dev, &fod->rspiubuf,
+					sizeof(fod->rspiubuf), DMA_TO_DEVICE);
+		if (fc_dma_mapping_error(tgtport->dev, fod->rspdma)) {
+			list_del(&fod->fcp_list);
+			for (fod--, i--; i >= 0; fod--, i--) {
+				fc_dma_unmap_single(tgtport->dev, fod->rspdma,
+						sizeof(fod->rspiubuf),
+						DMA_TO_DEVICE);
+				fod->rspdma = 0L;
+				list_del(&fod->fcp_list);
+			}
+
+			return;
+		}
+	}
+}
+
+static void
+nvmet_fc_destroy_fcp_iodlist(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_tgt_queue *queue)
+{
+	struct nvmet_fc_fcp_iod *fod = queue->fod;
+	int i;
+
+	for (i = 0; i < queue->sqsize; fod++, i++) {
+		if (fod->rspdma)
+			fc_dma_unmap_single(tgtport->dev, fod->rspdma,
+				sizeof(fod->rspiubuf), DMA_TO_DEVICE);
+	}
+}
+
+static struct nvmet_fc_fcp_iod *
+nvmet_fc_alloc_fcp_iod(struct nvmet_fc_tgt_queue *queue)
+{
+	struct nvmet_fc_fcp_iod *fod;
+
+	lockdep_assert_held(&queue->qlock);
+
+	fod = list_first_entry_or_null(&queue->fod_list,
+					struct nvmet_fc_fcp_iod, fcp_list);
+	if (fod) {
+		list_del(&fod->fcp_list);
+		fod->active = true;
+		/*
+		 * no queue reference is taken, as it was taken by the
+		 * queue lookup just prior to the allocation. The iod
+		 * will "inherit" that reference.
+		 */
+	}
+	return fod;
+}
+
+
+static void
+nvmet_fc_queue_fcp_req(struct nvmet_fc_tgtport *tgtport,
+		       struct nvmet_fc_tgt_queue *queue,
+		       struct nvmefc_tgt_fcp_req *fcpreq)
+{
+	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
+
+	/*
+	 * put all admin cmds on hw queue id 0. All io commands go to
+	 * the respective hw queue based on a modulo basis
+	 */
+	fcpreq->hwqid = queue->qid ?
+			((queue->qid - 1) % tgtport->ops->max_hw_queues) : 0;
+
+	nvmet_fc_handle_fcp_rqst(tgtport, fod);
+}
+
+static void
+nvmet_fc_fcp_rqst_op_defer_work(struct work_struct *work)
+{
+	struct nvmet_fc_fcp_iod *fod =
+		container_of(work, struct nvmet_fc_fcp_iod, defer_work);
+
+	/* Submit deferred IO for processing */
+	nvmet_fc_queue_fcp_req(fod->tgtport, fod->queue, fod->fcpreq);
+
+}
+
+static void
+nvmet_fc_free_fcp_iod(struct nvmet_fc_tgt_queue *queue,
+			struct nvmet_fc_fcp_iod *fod)
+{
+	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
+	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
+	struct nvmet_fc_defer_fcp_req *deferfcp;
+	unsigned long flags;
+
+	fc_dma_sync_single_for_cpu(tgtport->dev, fod->rspdma,
+				sizeof(fod->rspiubuf), DMA_TO_DEVICE);
+
+	fcpreq->nvmet_fc_private = NULL;
+
+	fod->active = false;
+	fod->abort = false;
+	fod->aborted = false;
+	fod->writedataactive = false;
+	fod->fcpreq = NULL;
+
+	tgtport->ops->fcp_req_release(&tgtport->fc_target_port, fcpreq);
+
+	/* release the queue lookup reference on the completed IO */
+	nvmet_fc_tgt_q_put(queue);
+
+	spin_lock_irqsave(&queue->qlock, flags);
+	deferfcp = list_first_entry_or_null(&queue->pending_cmd_list,
+				struct nvmet_fc_defer_fcp_req, req_list);
+	if (!deferfcp) {
+		list_add_tail(&fod->fcp_list, &fod->queue->fod_list);
+		spin_unlock_irqrestore(&queue->qlock, flags);
+		return;
+	}
+
+	/* Re-use the fod for the next pending cmd that was deferred */
+	list_del(&deferfcp->req_list);
+
+	fcpreq = deferfcp->fcp_req;
+
+	/* deferfcp can be reused for another IO at a later date */
+	list_add_tail(&deferfcp->req_list, &queue->avail_defer_list);
+
+	spin_unlock_irqrestore(&queue->qlock, flags);
+
+	/* Save NVME CMD IO in fod */
+	memcpy(&fod->cmdiubuf, fcpreq->rspaddr, fcpreq->rsplen);
+
+	/* Setup new fcpreq to be processed */
+	fcpreq->rspaddr = NULL;
+	fcpreq->rsplen  = 0;
+	fcpreq->nvmet_fc_private = fod;
+	fod->fcpreq = fcpreq;
+	fod->active = true;
+
+	/* inform LLDD IO is now being processed */
+	tgtport->ops->defer_rcv(&tgtport->fc_target_port, fcpreq);
+
+	/*
+	 * Leave the queue lookup get reference taken when
+	 * fod was originally allocated.
+	 */
+
+	queue_work(queue->work_q, &fod->defer_work);
+}
+
+static struct nvmet_fc_tgt_queue *
+nvmet_fc_alloc_target_queue(struct nvmet_fc_tgt_assoc *assoc,
+			u16 qid, u16 sqsize)
+{
+	struct nvmet_fc_tgt_queue *queue;
+	unsigned long flags;
+	int ret;
+
+	if (qid > NVMET_NR_QUEUES)
+		return NULL;
+
+	queue = kzalloc(struct_size(queue, fod, sqsize), GFP_KERNEL);
+	if (!queue)
+		return NULL;
+
+	if (!nvmet_fc_tgt_a_get(assoc))
+		goto out_free_queue;
+
+	queue->work_q = alloc_workqueue("ntfc%d.%d.%d", 0, 0,
+				assoc->tgtport->fc_target_port.port_num,
+				assoc->a_id, qid);
+	if (!queue->work_q)
+		goto out_a_put;
+
+	queue->qid = qid;
+	queue->sqsize = sqsize;
+	queue->assoc = assoc;
+	INIT_LIST_HEAD(&queue->fod_list);
+	INIT_LIST_HEAD(&queue->avail_defer_list);
+	INIT_LIST_HEAD(&queue->pending_cmd_list);
+	atomic_set(&queue->connected, 0);
+	atomic_set(&queue->sqtail, 0);
+	atomic_set(&queue->rsn, 1);
+	atomic_set(&queue->zrspcnt, 0);
+	spin_lock_init(&queue->qlock);
+	kref_init(&queue->ref);
+
+	nvmet_fc_prep_fcp_iodlist(assoc->tgtport, queue);
+
+	ret = nvmet_sq_init(&queue->nvme_sq);
+	if (ret)
+		goto out_fail_iodlist;
+
+	WARN_ON(assoc->queues[qid]);
+	spin_lock_irqsave(&assoc->tgtport->lock, flags);
+	assoc->queues[qid] = queue;
+	spin_unlock_irqrestore(&assoc->tgtport->lock, flags);
+
+	return queue;
+
+out_fail_iodlist:
+	nvmet_fc_destroy_fcp_iodlist(assoc->tgtport, queue);
+	destroy_workqueue(queue->work_q);
+out_a_put:
+	nvmet_fc_tgt_a_put(assoc);
+out_free_queue:
+	kfree(queue);
+	return NULL;
+}
+
+
+static void
+nvmet_fc_tgt_queue_free(struct kref *ref)
+{
+	struct nvmet_fc_tgt_queue *queue =
+		container_of(ref, struct nvmet_fc_tgt_queue, ref);
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->assoc->tgtport->lock, flags);
+	queue->assoc->queues[queue->qid] = NULL;
+	spin_unlock_irqrestore(&queue->assoc->tgtport->lock, flags);
+
+	nvmet_fc_destroy_fcp_iodlist(queue->assoc->tgtport, queue);
+
+	nvmet_fc_tgt_a_put(queue->assoc);
+
+	destroy_workqueue(queue->work_q);
+
+	kfree(queue);
+}
+
+static void
+nvmet_fc_tgt_q_put(struct nvmet_fc_tgt_queue *queue)
+{
+	kref_put(&queue->ref, nvmet_fc_tgt_queue_free);
+}
+
+static int
+nvmet_fc_tgt_q_get(struct nvmet_fc_tgt_queue *queue)
+{
+	return kref_get_unless_zero(&queue->ref);
+}
+
+
+static void
+nvmet_fc_delete_target_queue(struct nvmet_fc_tgt_queue *queue)
+{
+	struct nvmet_fc_tgtport *tgtport = queue->assoc->tgtport;
+	struct nvmet_fc_fcp_iod *fod = queue->fod;
+	struct nvmet_fc_defer_fcp_req *deferfcp, *tempptr;
+	unsigned long flags;
+	int i;
+	bool disconnect;
+
+	disconnect = atomic_xchg(&queue->connected, 0);
+
+	/* if not connected, nothing to do */
+	if (!disconnect)
+		return;
+
+	spin_lock_irqsave(&queue->qlock, flags);
+	/* abort outstanding io's */
+	for (i = 0; i < queue->sqsize; fod++, i++) {
+		if (fod->active) {
+			spin_lock(&fod->flock);
+			fod->abort = true;
+			/*
+			 * only call lldd abort routine if waiting for
+			 * writedata. other outstanding ops should finish
+			 * on their own.
+			 */
+			if (fod->writedataactive) {
+				fod->aborted = true;
+				spin_unlock(&fod->flock);
+				tgtport->ops->fcp_abort(
+					&tgtport->fc_target_port, fod->fcpreq);
+			} else
+				spin_unlock(&fod->flock);
+		}
+	}
+
+	/* Cleanup defer'ed IOs in queue */
+	list_for_each_entry_safe(deferfcp, tempptr, &queue->avail_defer_list,
+				req_list) {
+		list_del(&deferfcp->req_list);
+		kfree(deferfcp);
+	}
+
+	for (;;) {
+		deferfcp = list_first_entry_or_null(&queue->pending_cmd_list,
+				struct nvmet_fc_defer_fcp_req, req_list);
+		if (!deferfcp)
+			break;
+
+		list_del(&deferfcp->req_list);
+		spin_unlock_irqrestore(&queue->qlock, flags);
+
+		tgtport->ops->defer_rcv(&tgtport->fc_target_port,
+				deferfcp->fcp_req);
+
+		tgtport->ops->fcp_abort(&tgtport->fc_target_port,
+				deferfcp->fcp_req);
+
+		tgtport->ops->fcp_req_release(&tgtport->fc_target_port,
+				deferfcp->fcp_req);
+
+		/* release the queue lookup reference */
+		nvmet_fc_tgt_q_put(queue);
+
+		kfree(deferfcp);
+
+		spin_lock_irqsave(&queue->qlock, flags);
+	}
+	spin_unlock_irqrestore(&queue->qlock, flags);
+
+	flush_workqueue(queue->work_q);
+
+	nvmet_sq_destroy(&queue->nvme_sq);
+
+	nvmet_fc_tgt_q_put(queue);
+}
+
+static struct nvmet_fc_tgt_queue *
+nvmet_fc_find_target_queue(struct nvmet_fc_tgtport *tgtport,
+				u64 connection_id)
+{
+	struct nvmet_fc_tgt_assoc *assoc;
+	struct nvmet_fc_tgt_queue *queue;
+	u64 association_id = nvmet_fc_getassociationid(connection_id);
+	u16 qid = nvmet_fc_getqueueid(connection_id);
+	unsigned long flags;
+
+	if (qid > NVMET_NR_QUEUES)
+		return NULL;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_for_each_entry(assoc, &tgtport->assoc_list, a_list) {
+		if (association_id == assoc->association_id) {
+			queue = assoc->queues[qid];
+			if (queue &&
+			    (!atomic_read(&queue->connected) ||
+			     !nvmet_fc_tgt_q_get(queue)))
+				queue = NULL;
+			spin_unlock_irqrestore(&tgtport->lock, flags);
+			return queue;
+		}
+	}
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	return NULL;
+}
+
+static void
+nvmet_fc_hostport_free(struct kref *ref)
+{
+	struct nvmet_fc_hostport *hostport =
+		container_of(ref, struct nvmet_fc_hostport, ref);
+	struct nvmet_fc_tgtport *tgtport = hostport->tgtport;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_del(&hostport->host_list);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	if (tgtport->ops->host_release && hostport->invalid)
+		tgtport->ops->host_release(hostport->hosthandle);
+	kfree(hostport);
+	nvmet_fc_tgtport_put(tgtport);
+}
+
+static void
+nvmet_fc_hostport_put(struct nvmet_fc_hostport *hostport)
+{
+	kref_put(&hostport->ref, nvmet_fc_hostport_free);
+}
+
+static int
+nvmet_fc_hostport_get(struct nvmet_fc_hostport *hostport)
+{
+	return kref_get_unless_zero(&hostport->ref);
+}
+
+static void
+nvmet_fc_free_hostport(struct nvmet_fc_hostport *hostport)
+{
+	/* if LLDD not implemented, leave as NULL */
+	if (!hostport || !hostport->hosthandle)
+		return;
+
+	nvmet_fc_hostport_put(hostport);
+}
+
+static struct nvmet_fc_hostport *
+nvmet_fc_alloc_hostport(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
+{
+	struct nvmet_fc_hostport *newhost, *host, *match = NULL;
+	unsigned long flags;
+
+	/* if LLDD not implemented, leave as NULL */
+	if (!hosthandle)
+		return NULL;
+
+	/* take reference for what will be the newly allocated hostport */
+	if (!nvmet_fc_tgtport_get(tgtport))
+		return ERR_PTR(-EINVAL);
+
+	newhost = kzalloc(sizeof(*newhost), GFP_KERNEL);
+	if (!newhost) {
+		spin_lock_irqsave(&tgtport->lock, flags);
+		list_for_each_entry(host, &tgtport->host_list, host_list) {
+			if (host->hosthandle == hosthandle && !host->invalid) {
+				if (nvmet_fc_hostport_get(host)) {
+					match = host;
+					break;
+				}
+			}
+		}
+		spin_unlock_irqrestore(&tgtport->lock, flags);
+		/* no allocation - release reference */
+		nvmet_fc_tgtport_put(tgtport);
+		return (match) ? match : ERR_PTR(-ENOMEM);
+	}
+
+	newhost->tgtport = tgtport;
+	newhost->hosthandle = hosthandle;
+	INIT_LIST_HEAD(&newhost->host_list);
+	kref_init(&newhost->ref);
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_for_each_entry(host, &tgtport->host_list, host_list) {
+		if (host->hosthandle == hosthandle && !host->invalid) {
+			if (nvmet_fc_hostport_get(host)) {
+				match = host;
+				break;
+			}
+		}
+	}
+	if (match) {
+		kfree(newhost);
+		newhost = NULL;
+		/* releasing allocation - release reference */
+		nvmet_fc_tgtport_put(tgtport);
+	} else
+		list_add_tail(&newhost->host_list, &tgtport->host_list);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	return (match) ? match : newhost;
+}
+
+static void
+nvmet_fc_delete_assoc(struct work_struct *work)
+{
+	struct nvmet_fc_tgt_assoc *assoc =
+		container_of(work, struct nvmet_fc_tgt_assoc, del_work);
+
+	nvmet_fc_delete_target_assoc(assoc);
+	nvmet_fc_tgt_a_put(assoc);
+}
+
+static struct nvmet_fc_tgt_assoc *
+nvmet_fc_alloc_target_assoc(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
+{
+	struct nvmet_fc_tgt_assoc *assoc, *tmpassoc;
+	unsigned long flags;
+	u64 ran;
+	int idx;
+	bool needrandom = true;
+
+	assoc = kzalloc(sizeof(*assoc), GFP_KERNEL);
+	if (!assoc)
+		return NULL;
+
+	idx = ida_simple_get(&tgtport->assoc_cnt, 0, 0, GFP_KERNEL);
+	if (idx < 0)
+		goto out_free_assoc;
+
+	if (!nvmet_fc_tgtport_get(tgtport))
+		goto out_ida;
+
+	assoc->hostport = nvmet_fc_alloc_hostport(tgtport, hosthandle);
+	if (IS_ERR(assoc->hostport))
+		goto out_put;
+
+	assoc->tgtport = tgtport;
+	assoc->a_id = idx;
+	INIT_LIST_HEAD(&assoc->a_list);
+	kref_init(&assoc->ref);
+	INIT_WORK(&assoc->del_work, nvmet_fc_delete_assoc);
+	atomic_set(&assoc->terminating, 0);
+
+	while (needrandom) {
+		get_random_bytes(&ran, sizeof(ran) - BYTES_FOR_QID);
+		ran = ran << BYTES_FOR_QID_SHIFT;
+
+		spin_lock_irqsave(&tgtport->lock, flags);
+		needrandom = false;
+		list_for_each_entry(tmpassoc, &tgtport->assoc_list, a_list) {
+			if (ran == tmpassoc->association_id) {
+				needrandom = true;
+				break;
+			}
+		}
+		if (!needrandom) {
+			assoc->association_id = ran;
+			list_add_tail(&assoc->a_list, &tgtport->assoc_list);
+		}
+		spin_unlock_irqrestore(&tgtport->lock, flags);
+	}
+
+	return assoc;
+
+out_put:
+	nvmet_fc_tgtport_put(tgtport);
+out_ida:
+	ida_simple_remove(&tgtport->assoc_cnt, idx);
+out_free_assoc:
+	kfree(assoc);
+	return NULL;
+}
+
+static void
+nvmet_fc_target_assoc_free(struct kref *ref)
+{
+	struct nvmet_fc_tgt_assoc *assoc =
+		container_of(ref, struct nvmet_fc_tgt_assoc, ref);
+	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
+	struct nvmet_fc_ls_iod	*oldls;
+	unsigned long flags;
+
+	/* Send Disconnect now that all i/o has completed */
+	nvmet_fc_xmt_disconnect_assoc(assoc);
+
+	nvmet_fc_free_hostport(assoc->hostport);
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_del(&assoc->a_list);
+	oldls = assoc->rcv_disconn;
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	/* if pending Rcv Disconnect Association LS, send rsp now */
+	if (oldls)
+		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
+	ida_simple_remove(&tgtport->assoc_cnt, assoc->a_id);
+	dev_info(tgtport->dev,
+		"{%d:%d} Association freed\n",
+		tgtport->fc_target_port.port_num, assoc->a_id);
+	kfree(assoc);
+	nvmet_fc_tgtport_put(tgtport);
+}
+
+static void
+nvmet_fc_tgt_a_put(struct nvmet_fc_tgt_assoc *assoc)
+{
+	kref_put(&assoc->ref, nvmet_fc_target_assoc_free);
+}
+
+static int
+nvmet_fc_tgt_a_get(struct nvmet_fc_tgt_assoc *assoc)
+{
+	return kref_get_unless_zero(&assoc->ref);
+}
+
+static void
+nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc)
+{
+	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
+	struct nvmet_fc_tgt_queue *queue;
+	unsigned long flags;
+	int i, terminating;
+
+	terminating = atomic_xchg(&assoc->terminating, 1);
+
+	/* if already terminating, do nothing */
+	if (terminating)
+		return;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	for (i = NVMET_NR_QUEUES; i >= 0; i--) {
+		queue = assoc->queues[i];
+		if (queue) {
+			if (!nvmet_fc_tgt_q_get(queue))
+				continue;
+			spin_unlock_irqrestore(&tgtport->lock, flags);
+			nvmet_fc_delete_target_queue(queue);
+			nvmet_fc_tgt_q_put(queue);
+			spin_lock_irqsave(&tgtport->lock, flags);
+		}
+	}
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	dev_info(tgtport->dev,
+		"{%d:%d} Association deleted\n",
+		tgtport->fc_target_port.port_num, assoc->a_id);
+
+	nvmet_fc_tgt_a_put(assoc);
+}
+
+static struct nvmet_fc_tgt_assoc *
+nvmet_fc_find_target_assoc(struct nvmet_fc_tgtport *tgtport,
+				u64 association_id)
+{
+	struct nvmet_fc_tgt_assoc *assoc;
+	struct nvmet_fc_tgt_assoc *ret = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_for_each_entry(assoc, &tgtport->assoc_list, a_list) {
+		if (association_id == assoc->association_id) {
+			ret = assoc;
+			if (!nvmet_fc_tgt_a_get(assoc))
+				ret = NULL;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	return ret;
+}
+
+static void
+nvmet_fc_portentry_bind(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_port_entry *pe,
+			struct nvmet_port *port)
+{
+	lockdep_assert_held(&nvmet_fc_tgtlock);
+
+	pe->tgtport = tgtport;
+	tgtport->pe = pe;
+
+	pe->port = port;
+	port->priv = pe;
+
+	pe->node_name = tgtport->fc_target_port.node_name;
+	pe->port_name = tgtport->fc_target_port.port_name;
+	INIT_LIST_HEAD(&pe->pe_list);
+
+	list_add_tail(&pe->pe_list, &nvmet_fc_portentry_list);
+}
+
+static void
+nvmet_fc_portentry_unbind(struct nvmet_fc_port_entry *pe)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	if (pe->tgtport)
+		pe->tgtport->pe = NULL;
+	list_del(&pe->pe_list);
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+}
+
+/*
+ * called when a targetport deregisters. Breaks the relationship
+ * with the nvmet port, but leaves the port_entry in place so that
+ * re-registration can resume operation.
+ */
+static void
+nvmet_fc_portentry_unbind_tgt(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_port_entry *pe;
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	pe = tgtport->pe;
+	if (pe)
+		pe->tgtport = NULL;
+	tgtport->pe = NULL;
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+}
+
+/*
+ * called when a new targetport is registered. Looks in the
+ * existing nvmet port_entries to see if the nvmet layer is
+ * configured for the targetport's wwn's. (the targetport existed,
+ * nvmet configured, the lldd unregistered the tgtport, and is now
+ * reregistering the same targetport).  If so, set the nvmet port
+ * port entry on the targetport.
+ */
+static void
+nvmet_fc_portentry_rebind_tgt(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_port_entry *pe;
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	list_for_each_entry(pe, &nvmet_fc_portentry_list, pe_list) {
+		if (tgtport->fc_target_port.node_name == pe->node_name &&
+		    tgtport->fc_target_port.port_name == pe->port_name) {
+			WARN_ON(pe->tgtport);
+			tgtport->pe = pe;
+			pe->tgtport = tgtport;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+}
+
+/**
+ * nvme_fc_register_targetport - transport entry point called by an
+ *                              LLDD to register the existence of a local
+ *                              NVME subystem 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 NULL.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvmet_fc_register_targetport(struct nvmet_fc_port_info *pinfo,
+			struct nvmet_fc_target_template *template,
+			struct device *dev,
+			struct nvmet_fc_target_port **portptr)
+{
+	struct nvmet_fc_tgtport *newrec;
+	unsigned long flags;
+	int ret, idx;
+
+	if (!template->xmt_ls_rsp || !template->fcp_op ||
+	    !template->fcp_abort ||
+	    !template->fcp_req_release || !template->targetport_delete ||
+	    !template->max_hw_queues || !template->max_sgl_segments ||
+	    !template->max_dif_sgl_segments || !template->dma_boundary) {
+		ret = -EINVAL;
+		goto out_regtgt_failed;
+	}
+
+	newrec = kzalloc((sizeof(*newrec) + template->target_priv_sz),
+			 GFP_KERNEL);
+	if (!newrec) {
+		ret = -ENOMEM;
+		goto out_regtgt_failed;
+	}
+
+	idx = ida_simple_get(&nvmet_fc_tgtport_cnt, 0, 0, GFP_KERNEL);
+	if (idx < 0) {
+		ret = -ENOSPC;
+		goto out_fail_kfree;
+	}
+
+	if (!get_device(dev) && dev) {
+		ret = -ENODEV;
+		goto out_ida_put;
+	}
+
+	newrec->fc_target_port.node_name = pinfo->node_name;
+	newrec->fc_target_port.port_name = pinfo->port_name;
+	if (template->target_priv_sz)
+		newrec->fc_target_port.private = &newrec[1];
+	else
+		newrec->fc_target_port.private = NULL;
+	newrec->fc_target_port.port_id = pinfo->port_id;
+	newrec->fc_target_port.port_num = idx;
+	INIT_LIST_HEAD(&newrec->tgt_list);
+	newrec->dev = dev;
+	newrec->ops = template;
+	spin_lock_init(&newrec->lock);
+	INIT_LIST_HEAD(&newrec->ls_rcv_list);
+	INIT_LIST_HEAD(&newrec->ls_req_list);
+	INIT_LIST_HEAD(&newrec->ls_busylist);
+	INIT_LIST_HEAD(&newrec->assoc_list);
+	INIT_LIST_HEAD(&newrec->host_list);
+	kref_init(&newrec->ref);
+	ida_init(&newrec->assoc_cnt);
+	newrec->max_sg_cnt = template->max_sgl_segments;
+
+	ret = nvmet_fc_alloc_ls_iodlist(newrec);
+	if (ret) {
+		ret = -ENOMEM;
+		goto out_free_newrec;
+	}
+
+	nvmet_fc_portentry_rebind_tgt(newrec);
+
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	list_add_tail(&newrec->tgt_list, &nvmet_fc_target_list);
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+
+	*portptr = &newrec->fc_target_port;
+	return 0;
+
+out_free_newrec:
+	put_device(dev);
+out_ida_put:
+	ida_simple_remove(&nvmet_fc_tgtport_cnt, idx);
+out_fail_kfree:
+	kfree(newrec);
+out_regtgt_failed:
+	*portptr = NULL;
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_register_targetport);
+
+
+static void
+nvmet_fc_free_tgtport(struct kref *ref)
+{
+	struct nvmet_fc_tgtport *tgtport =
+		container_of(ref, struct nvmet_fc_tgtport, ref);
+	struct device *dev = tgtport->dev;
+	unsigned long flags;
+
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	list_del(&tgtport->tgt_list);
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+
+	nvmet_fc_free_ls_iodlist(tgtport);
+
+	/* let the LLDD know we've finished tearing it down */
+	tgtport->ops->targetport_delete(&tgtport->fc_target_port);
+
+	ida_simple_remove(&nvmet_fc_tgtport_cnt,
+			tgtport->fc_target_port.port_num);
+
+	ida_destroy(&tgtport->assoc_cnt);
+
+	kfree(tgtport);
+
+	put_device(dev);
+}
+
+static void
+nvmet_fc_tgtport_put(struct nvmet_fc_tgtport *tgtport)
+{
+	kref_put(&tgtport->ref, nvmet_fc_free_tgtport);
+}
+
+static int
+nvmet_fc_tgtport_get(struct nvmet_fc_tgtport *tgtport)
+{
+	return kref_get_unless_zero(&tgtport->ref);
+}
+
+static void
+__nvmet_fc_free_assocs(struct nvmet_fc_tgtport *tgtport)
+{
+	struct nvmet_fc_tgt_assoc *assoc, *next;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_for_each_entry_safe(assoc, next,
+				&tgtport->assoc_list, a_list) {
+		if (!nvmet_fc_tgt_a_get(assoc))
+			continue;
+		if (!schedule_work(&assoc->del_work))
+			/* already deleting - release local reference */
+			nvmet_fc_tgt_a_put(assoc);
+	}
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+}
+
+/**
+ * nvmet_fc_invalidate_host - transport entry point called by an LLDD
+ *                       to remove references to a hosthandle for LS's.
+ *
+ * The nvmet-fc layer ensures that any references to the hosthandle
+ * on the targetport are forgotten (set to NULL).  The LLDD will
+ * typically call this when a login with a remote host port has been
+ * lost, thus LS's for the remote host port are no longer possible.
+ *
+ * If an LS request is outstanding to the targetport/hosthandle (or
+ * issued concurrently with the call to invalidate the host), the
+ * LLDD is responsible for terminating/aborting the LS and completing
+ * the LS request. It is recommended that these terminations/aborts
+ * occur after calling to invalidate the host handle to avoid additional
+ * retries by the nvmet-fc transport. The nvmet-fc transport may
+ * continue to reference host handle while it cleans up outstanding
+ * NVME associations. The nvmet-fc transport will call the
+ * ops->host_release() callback to notify the LLDD that all references
+ * are complete and the related host handle can be recovered.
+ * Note: if there are no references, the callback may be called before
+ * the invalidate host call returns.
+ *
+ * @target_port: pointer to the (registered) target port that a prior
+ *              LS was received on and which supplied the transport the
+ *              hosthandle.
+ * @hosthandle: the handle (pointer) that represents the host port
+ *              that no longer has connectivity and that LS's should
+ *              no longer be directed to.
+ */
+void
+nvmet_fc_invalidate_host(struct nvmet_fc_target_port *target_port,
+			void *hosthandle)
+{
+	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
+	struct nvmet_fc_tgt_assoc *assoc, *next;
+	unsigned long flags;
+	bool noassoc = true;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+	list_for_each_entry_safe(assoc, next,
+				&tgtport->assoc_list, a_list) {
+		if (!assoc->hostport ||
+		    assoc->hostport->hosthandle != hosthandle)
+			continue;
+		if (!nvmet_fc_tgt_a_get(assoc))
+			continue;
+		assoc->hostport->invalid = 1;
+		noassoc = false;
+		if (!schedule_work(&assoc->del_work))
+			/* already deleting - release local reference */
+			nvmet_fc_tgt_a_put(assoc);
+	}
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	/* if there's nothing to wait for - call the callback */
+	if (noassoc && tgtport->ops->host_release)
+		tgtport->ops->host_release(hosthandle);
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_invalidate_host);
+
+/*
+ * nvmet layer has called to terminate an association
+ */
+static void
+nvmet_fc_delete_ctrl(struct nvmet_ctrl *ctrl)
+{
+	struct nvmet_fc_tgtport *tgtport, *next;
+	struct nvmet_fc_tgt_assoc *assoc;
+	struct nvmet_fc_tgt_queue *queue;
+	unsigned long flags;
+	bool found_ctrl = false;
+
+	/* this is a bit ugly, but don't want to make locks layered */
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	list_for_each_entry_safe(tgtport, next, &nvmet_fc_target_list,
+			tgt_list) {
+		if (!nvmet_fc_tgtport_get(tgtport))
+			continue;
+		spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+
+		spin_lock_irqsave(&tgtport->lock, flags);
+		list_for_each_entry(assoc, &tgtport->assoc_list, a_list) {
+			queue = assoc->queues[0];
+			if (queue && queue->nvme_sq.ctrl == ctrl) {
+				if (nvmet_fc_tgt_a_get(assoc))
+					found_ctrl = true;
+				break;
+			}
+		}
+		spin_unlock_irqrestore(&tgtport->lock, flags);
+
+		nvmet_fc_tgtport_put(tgtport);
+
+		if (found_ctrl) {
+			if (!schedule_work(&assoc->del_work))
+				/* already deleting - release local reference */
+				nvmet_fc_tgt_a_put(assoc);
+			return;
+		}
+
+		spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	}
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+}
+
+/**
+ * nvme_fc_unregister_targetport - transport entry point called by an
+ *                              LLDD to deregister/remove a previously
+ *                              registered a local NVME subsystem FC port.
+ * @target_port: pointer to the (registered) target port that is to be
+ *               deregistered.
+ *
+ * Returns:
+ * a completion status. Must be 0 upon success; a negative errno
+ * (ex: -ENXIO) upon failure.
+ */
+int
+nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *target_port)
+{
+	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
+
+	nvmet_fc_portentry_unbind_tgt(tgtport);
+
+	/* terminate any outstanding associations */
+	__nvmet_fc_free_assocs(tgtport);
+
+	/*
+	 * should terminate LS's as well. However, LS's will be generated
+	 * at the tail end of association termination, so they likely don't
+	 * exist yet. And even if they did, it's worthwhile to just let
+	 * them finish and targetport ref counting will clean things up.
+	 */
+
+	nvmet_fc_tgtport_put(tgtport);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_unregister_targetport);
+
+
+/* ********************** FC-NVME LS RCV Handling ************************* */
+
+
+static void
+nvmet_fc_ls_create_association(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_ls_iod *iod)
+{
+	struct fcnvme_ls_cr_assoc_rqst *rqst = &iod->rqstbuf->rq_cr_assoc;
+	struct fcnvme_ls_cr_assoc_acc *acc = &iod->rspbuf->rsp_cr_assoc;
+	struct nvmet_fc_tgt_queue *queue;
+	int ret = 0;
+
+	memset(acc, 0, sizeof(*acc));
+
+	/*
+	 * FC-NVME spec changes. There are initiators sending different
+	 * lengths as padding sizes for Create Association Cmd descriptor
+	 * was incorrect.
+	 * Accept anything of "minimum" length. Assume format per 1.15
+	 * spec (with HOSTID reduced to 16 bytes), ignore how long the
+	 * trailing pad length is.
+	 */
+	if (iod->rqstdatalen < FCNVME_LSDESC_CRA_RQST_MINLEN)
+		ret = VERR_CR_ASSOC_LEN;
+	else if (be32_to_cpu(rqst->desc_list_len) <
+			FCNVME_LSDESC_CRA_RQST_MIN_LISTLEN)
+		ret = VERR_CR_ASSOC_RQST_LEN;
+	else if (rqst->assoc_cmd.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_CREATE_ASSOC_CMD))
+		ret = VERR_CR_ASSOC_CMD;
+	else if (be32_to_cpu(rqst->assoc_cmd.desc_len) <
+			FCNVME_LSDESC_CRA_CMD_DESC_MIN_DESCLEN)
+		ret = VERR_CR_ASSOC_CMD_LEN;
+	else if (!rqst->assoc_cmd.ersp_ratio ||
+		 (be16_to_cpu(rqst->assoc_cmd.ersp_ratio) >=
+				be16_to_cpu(rqst->assoc_cmd.sqsize)))
+		ret = VERR_ERSP_RATIO;
+
+	else {
+		/* new association w/ admin queue */
+		iod->assoc = nvmet_fc_alloc_target_assoc(
+						tgtport, iod->hosthandle);
+		if (!iod->assoc)
+			ret = VERR_ASSOC_ALLOC_FAIL;
+		else {
+			queue = nvmet_fc_alloc_target_queue(iod->assoc, 0,
+					be16_to_cpu(rqst->assoc_cmd.sqsize));
+			if (!queue) {
+				ret = VERR_QUEUE_ALLOC_FAIL;
+				nvmet_fc_tgt_a_put(iod->assoc);
+			}
+		}
+	}
+
+	if (ret) {
+		dev_err(tgtport->dev,
+			"Create Association LS failed: %s\n",
+			validation_errors[ret]);
+		iod->lsrsp->rsplen = nvme_fc_format_rjt(acc,
+				sizeof(*acc), rqst->w0.ls_cmd,
+				FCNVME_RJT_RC_LOGIC,
+				FCNVME_RJT_EXP_NONE, 0);
+		return;
+	}
+
+	queue->ersp_ratio = be16_to_cpu(rqst->assoc_cmd.ersp_ratio);
+	atomic_set(&queue->connected, 1);
+	queue->sqhd = 0;	/* best place to init value */
+
+	dev_info(tgtport->dev,
+		"{%d:%d} Association created\n",
+		tgtport->fc_target_port.port_num, iod->assoc->a_id);
+
+	/* format a response */
+
+	iod->lsrsp->rsplen = sizeof(*acc);
+
+	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_ls_cr_assoc_acc)),
+			FCNVME_LS_CREATE_ASSOCIATION);
+	acc->associd.desc_tag = cpu_to_be32(FCNVME_LSDESC_ASSOC_ID);
+	acc->associd.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_assoc_id));
+	acc->associd.association_id =
+			cpu_to_be64(nvmet_fc_makeconnid(iod->assoc, 0));
+	acc->connectid.desc_tag = cpu_to_be32(FCNVME_LSDESC_CONN_ID);
+	acc->connectid.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_conn_id));
+	acc->connectid.connection_id = acc->associd.association_id;
+}
+
+static void
+nvmet_fc_ls_create_connection(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_ls_iod *iod)
+{
+	struct fcnvme_ls_cr_conn_rqst *rqst = &iod->rqstbuf->rq_cr_conn;
+	struct fcnvme_ls_cr_conn_acc *acc = &iod->rspbuf->rsp_cr_conn;
+	struct nvmet_fc_tgt_queue *queue;
+	int ret = 0;
+
+	memset(acc, 0, sizeof(*acc));
+
+	if (iod->rqstdatalen < sizeof(struct fcnvme_ls_cr_conn_rqst))
+		ret = VERR_CR_CONN_LEN;
+	else if (rqst->desc_list_len !=
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_ls_cr_conn_rqst)))
+		ret = VERR_CR_CONN_RQST_LEN;
+	else if (rqst->associd.desc_tag != cpu_to_be32(FCNVME_LSDESC_ASSOC_ID))
+		ret = VERR_ASSOC_ID;
+	else if (rqst->associd.desc_len !=
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_assoc_id)))
+		ret = VERR_ASSOC_ID_LEN;
+	else if (rqst->connect_cmd.desc_tag !=
+			cpu_to_be32(FCNVME_LSDESC_CREATE_CONN_CMD))
+		ret = VERR_CR_CONN_CMD;
+	else if (rqst->connect_cmd.desc_len !=
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_cr_conn_cmd)))
+		ret = VERR_CR_CONN_CMD_LEN;
+	else if (!rqst->connect_cmd.ersp_ratio ||
+		 (be16_to_cpu(rqst->connect_cmd.ersp_ratio) >=
+				be16_to_cpu(rqst->connect_cmd.sqsize)))
+		ret = VERR_ERSP_RATIO;
+
+	else {
+		/* new io queue */
+		iod->assoc = nvmet_fc_find_target_assoc(tgtport,
+				be64_to_cpu(rqst->associd.association_id));
+		if (!iod->assoc)
+			ret = VERR_NO_ASSOC;
+		else {
+			queue = nvmet_fc_alloc_target_queue(iod->assoc,
+					be16_to_cpu(rqst->connect_cmd.qid),
+					be16_to_cpu(rqst->connect_cmd.sqsize));
+			if (!queue)
+				ret = VERR_QUEUE_ALLOC_FAIL;
+
+			/* release get taken in nvmet_fc_find_target_assoc */
+			nvmet_fc_tgt_a_put(iod->assoc);
+		}
+	}
+
+	if (ret) {
+		dev_err(tgtport->dev,
+			"Create Connection LS failed: %s\n",
+			validation_errors[ret]);
+		iod->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;
+	}
+
+	queue->ersp_ratio = be16_to_cpu(rqst->connect_cmd.ersp_ratio);
+	atomic_set(&queue->connected, 1);
+	queue->sqhd = 0;	/* best place to init value */
+
+	/* format a response */
+
+	iod->lsrsp->rsplen = sizeof(*acc);
+
+	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
+			fcnvme_lsdesc_len(sizeof(struct fcnvme_ls_cr_conn_acc)),
+			FCNVME_LS_CREATE_CONNECTION);
+	acc->connectid.desc_tag = cpu_to_be32(FCNVME_LSDESC_CONN_ID);
+	acc->connectid.desc_len =
+			fcnvme_lsdesc_len(
+				sizeof(struct fcnvme_lsdesc_conn_id));
+	acc->connectid.connection_id =
+			cpu_to_be64(nvmet_fc_makeconnid(iod->assoc,
+				be16_to_cpu(rqst->connect_cmd.qid)));
+}
+
+/*
+ * Returns true if the LS response is to be transmit
+ * Returns false if the LS response is to be delayed
+ */
+static int
+nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_ls_iod *iod)
+{
+	struct fcnvme_ls_disconnect_assoc_rqst *rqst =
+						&iod->rqstbuf->rq_dis_assoc;
+	struct fcnvme_ls_disconnect_assoc_acc *acc =
+						&iod->rspbuf->rsp_dis_assoc;
+	struct nvmet_fc_tgt_assoc *assoc = NULL;
+	struct nvmet_fc_ls_iod *oldls = NULL;
+	unsigned long flags;
+	int ret = 0;
+
+	memset(acc, 0, sizeof(*acc));
+
+	ret = nvmefc_vldt_lsreq_discon_assoc(iod->rqstdatalen, rqst);
+	if (!ret) {
+		/* match an active association - takes an assoc ref if !NULL */
+		assoc = nvmet_fc_find_target_assoc(tgtport,
+				be64_to_cpu(rqst->associd.association_id));
+		iod->assoc = assoc;
+		if (!assoc)
+			ret = VERR_NO_ASSOC;
+	}
+
+	if (ret || !assoc) {
+		dev_err(tgtport->dev,
+			"Disconnect LS failed: %s\n",
+			validation_errors[ret]);
+		iod->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 a response */
+
+	iod->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);
+
+	/* release get taken in nvmet_fc_find_target_assoc */
+	nvmet_fc_tgt_a_put(assoc);
+
+	/*
+	 * The rules for LS response says the response cannot
+	 * go back until ABTS's have been sent for all outstanding
+	 * I/O and a Disconnect Association LS has been sent.
+	 * So... save off the Disconnect LS to send the response
+	 * later. If there was a prior LS already saved, replace
+	 * it with the newer one and send a can't perform reject
+	 * on the older one.
+	 */
+	spin_lock_irqsave(&tgtport->lock, flags);
+	oldls = assoc->rcv_disconn;
+	assoc->rcv_disconn = iod;
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	nvmet_fc_delete_target_assoc(assoc);
+
+	if (oldls) {
+		dev_info(tgtport->dev,
+			"{%d:%d} Multiple Disconnect Association LS's "
+			"received\n",
+			tgtport->fc_target_port.port_num, assoc->a_id);
+		/* overwrite good response with bogus failure */
+		oldls->lsrsp->rsplen = nvme_fc_format_rjt(oldls->rspbuf,
+						sizeof(*iod->rspbuf),
+						/* ok to use rqst, LS is same */
+						rqst->w0.ls_cmd,
+						FCNVME_RJT_RC_UNAB,
+						FCNVME_RJT_EXP_NONE, 0);
+		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
+	}
+
+	return false;
+}
+
+
+/* *********************** NVME Ctrl Routines **************************** */
+
+
+static void nvmet_fc_fcp_nvme_cmd_done(struct nvmet_req *nvme_req);
+
+static const struct nvmet_fabrics_ops nvmet_fc_tgt_fcp_ops;
+
+static void
+nvmet_fc_xmt_ls_rsp_done(struct nvmefc_ls_rsp *lsrsp)
+{
+	struct nvmet_fc_ls_iod *iod = lsrsp->nvme_fc_private;
+	struct nvmet_fc_tgtport *tgtport = iod->tgtport;
+
+	fc_dma_sync_single_for_cpu(tgtport->dev, iod->rspdma,
+				sizeof(*iod->rspbuf), DMA_TO_DEVICE);
+	nvmet_fc_free_ls_iod(tgtport, iod);
+	nvmet_fc_tgtport_put(tgtport);
+}
+
+static void
+nvmet_fc_xmt_ls_rsp(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_ls_iod *iod)
+{
+	int ret;
+
+	fc_dma_sync_single_for_device(tgtport->dev, iod->rspdma,
+				  sizeof(*iod->rspbuf), DMA_TO_DEVICE);
+
+	ret = tgtport->ops->xmt_ls_rsp(&tgtport->fc_target_port, iod->lsrsp);
+	if (ret)
+		nvmet_fc_xmt_ls_rsp_done(iod->lsrsp);
+}
+
+/*
+ * Actual processing routine for received FC-NVME LS Requests from the LLD
+ */
+static void
+nvmet_fc_handle_ls_rqst(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_ls_iod *iod)
+{
+	struct fcnvme_ls_rqst_w0 *w0 = &iod->rqstbuf->rq_cr_assoc.w0;
+	bool sendrsp = true;
+
+	iod->lsrsp->nvme_fc_private = iod;
+	iod->lsrsp->rspbuf = iod->rspbuf;
+	iod->lsrsp->rspdma = iod->rspdma;
+	iod->lsrsp->done = nvmet_fc_xmt_ls_rsp_done;
+	/* Be preventative. handlers will later set to valid length */
+	iod->lsrsp->rsplen = 0;
+
+	iod->assoc = NULL;
+
+	/*
+	 * handlers:
+	 *   parse request input, execute the request, and format the
+	 *   LS response
+	 */
+	switch (w0->ls_cmd) {
+	case FCNVME_LS_CREATE_ASSOCIATION:
+		/* Creates Association and initial Admin Queue/Connection */
+		nvmet_fc_ls_create_association(tgtport, iod);
+		break;
+	case FCNVME_LS_CREATE_CONNECTION:
+		/* Creates an IO Queue/Connection */
+		nvmet_fc_ls_create_connection(tgtport, iod);
+		break;
+	case FCNVME_LS_DISCONNECT_ASSOC:
+		/* Terminate a Queue/Connection or the Association */
+		sendrsp = nvmet_fc_ls_disconnect(tgtport, iod);
+		break;
+	default:
+		iod->lsrsp->rsplen = nvme_fc_format_rjt(iod->rspbuf,
+				sizeof(*iod->rspbuf), w0->ls_cmd,
+				FCNVME_RJT_RC_INVAL, FCNVME_RJT_EXP_NONE, 0);
+	}
+
+	if (sendrsp)
+		nvmet_fc_xmt_ls_rsp(tgtport, iod);
+}
+
+/*
+ * Actual processing routine for received FC-NVME LS Requests from the LLD
+ */
+static void
+nvmet_fc_handle_ls_rqst_work(struct work_struct *work)
+{
+	struct nvmet_fc_ls_iod *iod =
+		container_of(work, struct nvmet_fc_ls_iod, work);
+	struct nvmet_fc_tgtport *tgtport = iod->tgtport;
+
+	nvmet_fc_handle_ls_rqst(tgtport, iod);
+}
+
+
+/**
+ * nvmet_fc_rcv_ls_req - transport entry point called by an LLDD
+ *                       upon the reception of a NVME LS request.
+ *
+ * The nvmet-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.
+ *
+ * @target_port: pointer to the (registered) target port the LS was
+ *              received on.
+ * @lsrsp:      pointer to a lsrsp structure to be used to reference
+ *              the exchange corresponding to the LS.
+ * @lsreqbuf:   pointer to the buffer containing the LS Request
+ * @lsreqbuf_len: length, in bytes, of the received LS request
+ */
+int
+nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *target_port,
+			void *hosthandle,
+			struct nvmefc_ls_rsp *lsrsp,
+			void *lsreqbuf, u32 lsreqbuf_len)
+{
+	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
+	struct nvmet_fc_ls_iod *iod;
+	struct fcnvme_ls_rqst_w0 *w0 = (struct fcnvme_ls_rqst_w0 *)lsreqbuf;
+
+	if (lsreqbuf_len > sizeof(union nvmefc_ls_requests)) {
+		dev_info(tgtport->dev,
+			"RCV %s LS failed: payload too large (%d)\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "",
+			lsreqbuf_len);
+		return -E2BIG;
+	}
+
+	if (!nvmet_fc_tgtport_get(tgtport)) {
+		dev_info(tgtport->dev,
+			"RCV %s LS failed: target deleting\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		return -ESHUTDOWN;
+	}
+
+	iod = nvmet_fc_alloc_ls_iod(tgtport);
+	if (!iod) {
+		dev_info(tgtport->dev,
+			"RCV %s LS failed: context allocation failed\n",
+			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
+				nvmefc_ls_names[w0->ls_cmd] : "");
+		nvmet_fc_tgtport_put(tgtport);
+		return -ENOENT;
+	}
+
+	iod->lsrsp = lsrsp;
+	iod->fcpreq = NULL;
+	memcpy(iod->rqstbuf, lsreqbuf, lsreqbuf_len);
+	iod->rqstdatalen = lsreqbuf_len;
+	iod->hosthandle = hosthandle;
+
+	schedule_work(&iod->work);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_rcv_ls_req);
+
+
+/*
+ * **********************
+ * Start of FCP handling
+ * **********************
+ */
+
+static int
+nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
+{
+	struct scatterlist *sg;
+	unsigned int nent;
+
+	sg = sgl_alloc(fod->req.transfer_len, GFP_KERNEL, &nent);
+	if (!sg)
+		goto out;
+
+	fod->data_sg = sg;
+	fod->data_sg_cnt = nent;
+	fod->data_sg_cnt = fc_dma_map_sg(fod->tgtport->dev, sg, nent,
+				((fod->io_dir == NVMET_FCP_WRITE) ?
+					DMA_FROM_DEVICE : DMA_TO_DEVICE));
+				/* note: write from initiator perspective */
+	fod->next_sg = fod->data_sg;
+
+	return 0;
+
+out:
+	return NVME_SC_INTERNAL;
+}
+
+static void
+nvmet_fc_free_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
+{
+	if (!fod->data_sg || !fod->data_sg_cnt)
+		return;
+
+	fc_dma_unmap_sg(fod->tgtport->dev, fod->data_sg, fod->data_sg_cnt,
+				((fod->io_dir == NVMET_FCP_WRITE) ?
+					DMA_FROM_DEVICE : DMA_TO_DEVICE));
+	sgl_free(fod->data_sg);
+	fod->data_sg = NULL;
+	fod->data_sg_cnt = 0;
+}
+
+
+static bool
+queue_90percent_full(struct nvmet_fc_tgt_queue *q, u32 sqhd)
+{
+	u32 sqtail, used;
+
+	/* egad, this is ugly. And sqtail is just a best guess */
+	sqtail = atomic_read(&q->sqtail) % q->sqsize;
+
+	used = (sqtail < sqhd) ? (sqtail + q->sqsize - sqhd) : (sqtail - sqhd);
+	return ((used * 10) >= (((u32)(q->sqsize - 1) * 9)));
+}
+
+/*
+ * Prep RSP payload.
+ * May be a NVMET_FCOP_RSP or NVMET_FCOP_READDATA_RSP op
+ */
+static void
+nvmet_fc_prep_fcp_rsp(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_fcp_iod *fod)
+{
+	struct nvme_fc_ersp_iu *ersp = &fod->rspiubuf;
+	struct nvme_common_command *sqe = &fod->cmdiubuf.sqe.common;
+	struct nvme_completion *cqe = &ersp->cqe;
+	u32 *cqewd = (u32 *)cqe;
+	bool send_ersp = false;
+	u32 rsn, rspcnt, xfr_length;
+
+	if (fod->fcpreq->op == NVMET_FCOP_READDATA_RSP)
+		xfr_length = fod->req.transfer_len;
+	else
+		xfr_length = fod->offset;
+
+	/*
+	 * check to see if we can send a 0's rsp.
+	 *   Note: to send a 0's response, the NVME-FC host transport will
+	 *   recreate the CQE. The host transport knows: sq id, SQHD (last
+	 *   seen in an ersp), and command_id. Thus it will create a
+	 *   zero-filled CQE with those known fields filled in. Transport
+	 *   must send an ersp for any condition where the cqe won't match
+	 *   this.
+	 *
+	 * Here are the FC-NVME mandated cases where we must send an ersp:
+	 *  every N responses, where N=ersp_ratio
+	 *  force fabric commands to send ersp's (not in FC-NVME but good
+	 *    practice)
+	 *  normal cmds: any time status is non-zero, or status is zero
+	 *     but words 0 or 1 are non-zero.
+	 *  the SQ is 90% or more full
+	 *  the cmd is a fused command
+	 *  transferred data length not equal to cmd iu length
+	 */
+	rspcnt = atomic_inc_return(&fod->queue->zrspcnt);
+	if (!(rspcnt % fod->queue->ersp_ratio) ||
+	    nvme_is_fabrics((struct nvme_command *) sqe) ||
+	    xfr_length != fod->req.transfer_len ||
+	    (le16_to_cpu(cqe->status) & 0xFFFE) || cqewd[0] || cqewd[1] ||
+	    (sqe->flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND)) ||
+	    queue_90percent_full(fod->queue, le16_to_cpu(cqe->sq_head)))
+		send_ersp = true;
+
+	/* re-set the fields */
+	fod->fcpreq->rspaddr = ersp;
+	fod->fcpreq->rspdma = fod->rspdma;
+
+	if (!send_ersp) {
+		memset(ersp, 0, NVME_FC_SIZEOF_ZEROS_RSP);
+		fod->fcpreq->rsplen = NVME_FC_SIZEOF_ZEROS_RSP;
+	} else {
+		ersp->iu_len = cpu_to_be16(sizeof(*ersp)/sizeof(u32));
+		rsn = atomic_inc_return(&fod->queue->rsn);
+		ersp->rsn = cpu_to_be32(rsn);
+		ersp->xfrd_len = cpu_to_be32(xfr_length);
+		fod->fcpreq->rsplen = sizeof(*ersp);
+	}
+
+	fc_dma_sync_single_for_device(tgtport->dev, fod->rspdma,
+				  sizeof(fod->rspiubuf), DMA_TO_DEVICE);
+}
+
+static void nvmet_fc_xmt_fcp_op_done(struct nvmefc_tgt_fcp_req *fcpreq);
+
+static void
+nvmet_fc_abort_op(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_fcp_iod *fod)
+{
+	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
+
+	/* data no longer needed */
+	nvmet_fc_free_tgt_pgs(fod);
+
+	/*
+	 * if an ABTS was received or we issued the fcp_abort early
+	 * don't call abort routine again.
+	 */
+	/* no need to take lock - lock was taken earlier to get here */
+	if (!fod->aborted)
+		tgtport->ops->fcp_abort(&tgtport->fc_target_port, fcpreq);
+
+	nvmet_fc_free_fcp_iod(fod->queue, fod);
+}
+
+static void
+nvmet_fc_xmt_fcp_rsp(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_fcp_iod *fod)
+{
+	int ret;
+
+	fod->fcpreq->op = NVMET_FCOP_RSP;
+	fod->fcpreq->timeout = 0;
+
+	nvmet_fc_prep_fcp_rsp(tgtport, fod);
+
+	ret = tgtport->ops->fcp_op(&tgtport->fc_target_port, fod->fcpreq);
+	if (ret)
+		nvmet_fc_abort_op(tgtport, fod);
+}
+
+static void
+nvmet_fc_transfer_fcp_data(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_fcp_iod *fod, u8 op)
+{
+	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
+	struct scatterlist *sg = fod->next_sg;
+	unsigned long flags;
+	u32 remaininglen = fod->req.transfer_len - fod->offset;
+	u32 tlen = 0;
+	int ret;
+
+	fcpreq->op = op;
+	fcpreq->offset = fod->offset;
+	fcpreq->timeout = NVME_FC_TGTOP_TIMEOUT_SEC;
+
+	/*
+	 * for next sequence:
+	 *  break at a sg element boundary
+	 *  attempt to keep sequence length capped at
+	 *    NVMET_FC_MAX_SEQ_LENGTH but allow sequence to
+	 *    be longer if a single sg element is larger
+	 *    than that amount. This is done to avoid creating
+	 *    a new sg list to use for the tgtport api.
+	 */
+	fcpreq->sg = sg;
+	fcpreq->sg_cnt = 0;
+	while (tlen < remaininglen &&
+	       fcpreq->sg_cnt < tgtport->max_sg_cnt &&
+	       tlen + sg_dma_len(sg) < NVMET_FC_MAX_SEQ_LENGTH) {
+		fcpreq->sg_cnt++;
+		tlen += sg_dma_len(sg);
+		sg = sg_next(sg);
+	}
+	if (tlen < remaininglen && fcpreq->sg_cnt == 0) {
+		fcpreq->sg_cnt++;
+		tlen += min_t(u32, sg_dma_len(sg), remaininglen);
+		sg = sg_next(sg);
+	}
+	if (tlen < remaininglen)
+		fod->next_sg = sg;
+	else
+		fod->next_sg = NULL;
+
+	fcpreq->transfer_length = tlen;
+	fcpreq->transferred_length = 0;
+	fcpreq->fcp_error = 0;
+	fcpreq->rsplen = 0;
+
+	/*
+	 * If the last READDATA request: check if LLDD supports
+	 * combined xfr with response.
+	 */
+	if ((op == NVMET_FCOP_READDATA) &&
+	    ((fod->offset + fcpreq->transfer_length) == fod->req.transfer_len) &&
+	    (tgtport->ops->target_features & NVMET_FCTGTFEAT_READDATA_RSP)) {
+		fcpreq->op = NVMET_FCOP_READDATA_RSP;
+		nvmet_fc_prep_fcp_rsp(tgtport, fod);
+	}
+
+	ret = tgtport->ops->fcp_op(&tgtport->fc_target_port, fod->fcpreq);
+	if (ret) {
+		/*
+		 * should be ok to set w/o lock as its in the thread of
+		 * execution (not an async timer routine) and doesn't
+		 * contend with any clearing action
+		 */
+		fod->abort = true;
+
+		if (op == NVMET_FCOP_WRITEDATA) {
+			spin_lock_irqsave(&fod->flock, flags);
+			fod->writedataactive = false;
+			spin_unlock_irqrestore(&fod->flock, flags);
+			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
+		} else /* NVMET_FCOP_READDATA or NVMET_FCOP_READDATA_RSP */ {
+			fcpreq->fcp_error = ret;
+			fcpreq->transferred_length = 0;
+			nvmet_fc_xmt_fcp_op_done(fod->fcpreq);
+		}
+	}
+}
+
+static inline bool
+__nvmet_fc_fod_op_abort(struct nvmet_fc_fcp_iod *fod, bool abort)
+{
+	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
+	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
+
+	/* if in the middle of an io and we need to tear down */
+	if (abort) {
+		if (fcpreq->op == NVMET_FCOP_WRITEDATA) {
+			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
+			return true;
+		}
+
+		nvmet_fc_abort_op(tgtport, fod);
+		return true;
+	}
+
+	return false;
+}
+
+/*
+ * actual done handler for FCP operations when completed by the lldd
+ */
+static void
+nvmet_fc_fod_op_done(struct nvmet_fc_fcp_iod *fod)
+{
+	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
+	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
+	unsigned long flags;
+	bool abort;
+
+	spin_lock_irqsave(&fod->flock, flags);
+	abort = fod->abort;
+	fod->writedataactive = false;
+	spin_unlock_irqrestore(&fod->flock, flags);
+
+	switch (fcpreq->op) {
+
+	case NVMET_FCOP_WRITEDATA:
+		if (__nvmet_fc_fod_op_abort(fod, abort))
+			return;
+		if (fcpreq->fcp_error ||
+		    fcpreq->transferred_length != fcpreq->transfer_length) {
+			spin_lock_irqsave(&fod->flock, flags);
+			fod->abort = true;
+			spin_unlock_irqrestore(&fod->flock, flags);
+
+			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
+			return;
+		}
+
+		fod->offset += fcpreq->transferred_length;
+		if (fod->offset != fod->req.transfer_len) {
+			spin_lock_irqsave(&fod->flock, flags);
+			fod->writedataactive = true;
+			spin_unlock_irqrestore(&fod->flock, flags);
+
+			/* transfer the next chunk */
+			nvmet_fc_transfer_fcp_data(tgtport, fod,
+						NVMET_FCOP_WRITEDATA);
+			return;
+		}
+
+		/* data transfer complete, resume with nvmet layer */
+		fod->req.execute(&fod->req);
+		break;
+
+	case NVMET_FCOP_READDATA:
+	case NVMET_FCOP_READDATA_RSP:
+		if (__nvmet_fc_fod_op_abort(fod, abort))
+			return;
+		if (fcpreq->fcp_error ||
+		    fcpreq->transferred_length != fcpreq->transfer_length) {
+			nvmet_fc_abort_op(tgtport, fod);
+			return;
+		}
+
+		/* success */
+
+		if (fcpreq->op == NVMET_FCOP_READDATA_RSP) {
+			/* data no longer needed */
+			nvmet_fc_free_tgt_pgs(fod);
+			nvmet_fc_free_fcp_iod(fod->queue, fod);
+			return;
+		}
+
+		fod->offset += fcpreq->transferred_length;
+		if (fod->offset != fod->req.transfer_len) {
+			/* transfer the next chunk */
+			nvmet_fc_transfer_fcp_data(tgtport, fod,
+						NVMET_FCOP_READDATA);
+			return;
+		}
+
+		/* data transfer complete, send response */
+
+		/* data no longer needed */
+		nvmet_fc_free_tgt_pgs(fod);
+
+		nvmet_fc_xmt_fcp_rsp(tgtport, fod);
+
+		break;
+
+	case NVMET_FCOP_RSP:
+		if (__nvmet_fc_fod_op_abort(fod, abort))
+			return;
+		nvmet_fc_free_fcp_iod(fod->queue, fod);
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void
+nvmet_fc_xmt_fcp_op_done(struct nvmefc_tgt_fcp_req *fcpreq)
+{
+	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
+
+	nvmet_fc_fod_op_done(fod);
+}
+
+/*
+ * actual completion handler after execution by the nvmet layer
+ */
+static void
+__nvmet_fc_fcp_nvme_cmd_done(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_fcp_iod *fod, int status)
+{
+	struct nvme_common_command *sqe = &fod->cmdiubuf.sqe.common;
+	struct nvme_completion *cqe = &fod->rspiubuf.cqe;
+	unsigned long flags;
+	bool abort;
+
+	spin_lock_irqsave(&fod->flock, flags);
+	abort = fod->abort;
+	spin_unlock_irqrestore(&fod->flock, flags);
+
+	/* if we have a CQE, snoop the last sq_head value */
+	if (!status)
+		fod->queue->sqhd = cqe->sq_head;
+
+	if (abort) {
+		nvmet_fc_abort_op(tgtport, fod);
+		return;
+	}
+
+	/* if an error handling the cmd post initial parsing */
+	if (status) {
+		/* fudge up a failed CQE status for our transport error */
+		memset(cqe, 0, sizeof(*cqe));
+		cqe->sq_head = fod->queue->sqhd;	/* echo last cqe sqhd */
+		cqe->sq_id = cpu_to_le16(fod->queue->qid);
+		cqe->command_id = sqe->command_id;
+		cqe->status = cpu_to_le16(status);
+	} else {
+
+		/*
+		 * try to push the data even if the SQE status is non-zero.
+		 * There may be a status where data still was intended to
+		 * be moved
+		 */
+		if ((fod->io_dir == NVMET_FCP_READ) && (fod->data_sg_cnt)) {
+			/* push the data over before sending rsp */
+			nvmet_fc_transfer_fcp_data(tgtport, fod,
+						NVMET_FCOP_READDATA);
+			return;
+		}
+
+		/* writes & no data - fall thru */
+	}
+
+	/* data no longer needed */
+	nvmet_fc_free_tgt_pgs(fod);
+
+	nvmet_fc_xmt_fcp_rsp(tgtport, fod);
+}
+
+
+static void
+nvmet_fc_fcp_nvme_cmd_done(struct nvmet_req *nvme_req)
+{
+	struct nvmet_fc_fcp_iod *fod = nvmet_req_to_fod(nvme_req);
+	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
+
+	__nvmet_fc_fcp_nvme_cmd_done(tgtport, fod, 0);
+}
+
+
+/*
+ * Actual processing routine for received FC-NVME I/O Requests from the LLD
+ */
+static void
+nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
+			struct nvmet_fc_fcp_iod *fod)
+{
+	struct nvme_fc_cmd_iu *cmdiu = &fod->cmdiubuf;
+	u32 xfrlen = be32_to_cpu(cmdiu->data_len);
+	int ret;
+
+	/*
+	 * Fused commands are currently not supported in the linux
+	 * implementation.
+	 *
+	 * As such, the implementation of the FC transport does not
+	 * look at the fused commands and order delivery to the upper
+	 * layer until we have both based on csn.
+	 */
+
+	fod->fcpreq->done = nvmet_fc_xmt_fcp_op_done;
+
+	if (cmdiu->flags & FCNVME_CMD_FLAGS_WRITE) {
+		fod->io_dir = NVMET_FCP_WRITE;
+		if (!nvme_is_write(&cmdiu->sqe))
+			goto transport_error;
+	} else if (cmdiu->flags & FCNVME_CMD_FLAGS_READ) {
+		fod->io_dir = NVMET_FCP_READ;
+		if (nvme_is_write(&cmdiu->sqe))
+			goto transport_error;
+	} else {
+		fod->io_dir = NVMET_FCP_NODATA;
+		if (xfrlen)
+			goto transport_error;
+	}
+
+	fod->req.cmd = &fod->cmdiubuf.sqe;
+	fod->req.cqe = &fod->rspiubuf.cqe;
+	if (tgtport->pe)
+		fod->req.port = tgtport->pe->port;
+
+	/* clear any response payload */
+	memset(&fod->rspiubuf, 0, sizeof(fod->rspiubuf));
+
+	fod->data_sg = NULL;
+	fod->data_sg_cnt = 0;
+
+	ret = nvmet_req_init(&fod->req,
+				&fod->queue->nvme_cq,
+				&fod->queue->nvme_sq,
+				&nvmet_fc_tgt_fcp_ops);
+	if (!ret) {
+		/* bad SQE content or invalid ctrl state */
+		/* nvmet layer has already called op done to send rsp. */
+		return;
+	}
+
+	fod->req.transfer_len = xfrlen;
+
+	/* keep a running counter of tail position */
+	atomic_inc(&fod->queue->sqtail);
+
+	if (fod->req.transfer_len) {
+		ret = nvmet_fc_alloc_tgt_pgs(fod);
+		if (ret) {
+			nvmet_req_complete(&fod->req, ret);
+			return;
+		}
+	}
+	fod->req.sg = fod->data_sg;
+	fod->req.sg_cnt = fod->data_sg_cnt;
+	fod->offset = 0;
+
+	if (fod->io_dir == NVMET_FCP_WRITE) {
+		/* pull the data over before invoking nvmet layer */
+		nvmet_fc_transfer_fcp_data(tgtport, fod, NVMET_FCOP_WRITEDATA);
+		return;
+	}
+
+	/*
+	 * Reads or no data:
+	 *
+	 * can invoke the nvmet_layer now. If read data, cmd completion will
+	 * push the data
+	 */
+	fod->req.execute(&fod->req);
+	return;
+
+transport_error:
+	nvmet_fc_abort_op(tgtport, fod);
+}
+
+/**
+ * nvmet_fc_rcv_fcp_req - transport entry point called by an LLDD
+ *                       upon the reception of a NVME FCP CMD IU.
+ *
+ * Pass a FC-NVME FCP CMD IU received from the FC link to the nvmet-fc
+ * layer for processing.
+ *
+ * The nvmet_fc layer allocates a local job structure (struct
+ * nvmet_fc_fcp_iod) from the queue for the io and copies the
+ * CMD IU buffer to the job structure. As such, on a successful
+ * completion (returns 0), the LLDD may immediately free/reuse
+ * the CMD IU buffer passed in the call.
+ *
+ * However, in some circumstances, due to the packetized nature of FC
+ * and the api of the FC LLDD which may issue a hw command to send the
+ * response, but the LLDD may not get the hw completion for that command
+ * and upcall the nvmet_fc layer before a new command may be
+ * asynchronously received - its possible for a command to be received
+ * before the LLDD and nvmet_fc have recycled the job structure. It gives
+ * the appearance of more commands received than fits in the sq.
+ * To alleviate this scenario, a temporary queue is maintained in the
+ * transport for pending LLDD requests waiting for a queue job structure.
+ * In these "overrun" cases, a temporary queue element is allocated
+ * the LLDD request and CMD iu buffer information remembered, and the
+ * routine returns a -EOVERFLOW status. Subsequently, when a queue job
+ * structure is freed, it is immediately reallocated for anything on the
+ * pending request list. The LLDDs defer_rcv() callback is called,
+ * informing the LLDD that it may reuse the CMD IU buffer, and the io
+ * is then started normally with the transport.
+ *
+ * The LLDD, when receiving an -EOVERFLOW completion status, is to treat
+ * the completion as successful but must not reuse the CMD IU buffer
+ * until the LLDD's defer_rcv() callback has been called for the
+ * corresponding struct nvmefc_tgt_fcp_req pointer.
+ *
+ * If there is any other condition in which an error occurs, the
+ * transport will return a non-zero status indicating the error.
+ * In all cases other than -EOVERFLOW, the transport has not accepted the
+ * request and the LLDD should abort the exchange.
+ *
+ * @target_port: pointer to the (registered) target port the FCP CMD IU
+ *              was received on.
+ * @fcpreq:     pointer to a fcpreq request structure to be used to reference
+ *              the exchange corresponding to the FCP Exchange.
+ * @cmdiubuf:   pointer to the buffer containing the FCP CMD IU
+ * @cmdiubuf_len: length, in bytes, of the received FCP CMD IU
+ */
+int
+nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *target_port,
+			struct nvmefc_tgt_fcp_req *fcpreq,
+			void *cmdiubuf, u32 cmdiubuf_len)
+{
+	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
+	struct nvme_fc_cmd_iu *cmdiu = cmdiubuf;
+	struct nvmet_fc_tgt_queue *queue;
+	struct nvmet_fc_fcp_iod *fod;
+	struct nvmet_fc_defer_fcp_req *deferfcp;
+	unsigned long flags;
+
+	/* validate iu, so the connection id can be used to find the queue */
+	if ((cmdiubuf_len != sizeof(*cmdiu)) ||
+			(cmdiu->format_id != NVME_CMD_FORMAT_ID) ||
+			(cmdiu->fc_id != NVME_CMD_FC_ID) ||
+			(be16_to_cpu(cmdiu->iu_len) != (sizeof(*cmdiu)/4)))
+		return -EIO;
+
+	queue = nvmet_fc_find_target_queue(tgtport,
+				be64_to_cpu(cmdiu->connection_id));
+	if (!queue)
+		return -ENOTCONN;
+
+	/*
+	 * note: reference taken by find_target_queue
+	 * After successful fod allocation, the fod will inherit the
+	 * ownership of that reference and will remove the reference
+	 * when the fod is freed.
+	 */
+
+	spin_lock_irqsave(&queue->qlock, flags);
+
+	fod = nvmet_fc_alloc_fcp_iod(queue);
+	if (fod) {
+		spin_unlock_irqrestore(&queue->qlock, flags);
+
+		fcpreq->nvmet_fc_private = fod;
+		fod->fcpreq = fcpreq;
+
+		memcpy(&fod->cmdiubuf, cmdiubuf, cmdiubuf_len);
+
+		nvmet_fc_queue_fcp_req(tgtport, queue, fcpreq);
+
+		return 0;
+	}
+
+	if (!tgtport->ops->defer_rcv) {
+		spin_unlock_irqrestore(&queue->qlock, flags);
+		/* release the queue lookup reference */
+		nvmet_fc_tgt_q_put(queue);
+		return -ENOENT;
+	}
+
+	deferfcp = list_first_entry_or_null(&queue->avail_defer_list,
+			struct nvmet_fc_defer_fcp_req, req_list);
+	if (deferfcp) {
+		/* Just re-use one that was previously allocated */
+		list_del(&deferfcp->req_list);
+	} else {
+		spin_unlock_irqrestore(&queue->qlock, flags);
+
+		/* Now we need to dynamically allocate one */
+		deferfcp = kmalloc(sizeof(*deferfcp), GFP_KERNEL);
+		if (!deferfcp) {
+			/* release the queue lookup reference */
+			nvmet_fc_tgt_q_put(queue);
+			return -ENOMEM;
+		}
+		spin_lock_irqsave(&queue->qlock, flags);
+	}
+
+	/* For now, use rspaddr / rsplen to save payload information */
+	fcpreq->rspaddr = cmdiubuf;
+	fcpreq->rsplen  = cmdiubuf_len;
+	deferfcp->fcp_req = fcpreq;
+
+	/* defer processing till a fod becomes available */
+	list_add_tail(&deferfcp->req_list, &queue->pending_cmd_list);
+
+	/* NOTE: the queue lookup reference is still valid */
+
+	spin_unlock_irqrestore(&queue->qlock, flags);
+
+	return -EOVERFLOW;
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_rcv_fcp_req);
+
+/**
+ * nvmet_fc_rcv_fcp_abort - transport entry point called by an LLDD
+ *                       upon the reception of an ABTS for a FCP command
+ *
+ * Notify the transport that an ABTS has been received for a FCP command
+ * that had been given to the transport via nvmet_fc_rcv_fcp_req(). The
+ * LLDD believes the command is still being worked on
+ * (template_ops->fcp_req_release() has not been called).
+ *
+ * The transport will wait for any outstanding work (an op to the LLDD,
+ * which the lldd should complete with error due to the ABTS; or the
+ * completion from the nvmet layer of the nvme command), then will
+ * stop processing and call the nvmet_fc_rcv_fcp_req() callback to
+ * return the i/o context to the LLDD.  The LLDD may send the BA_ACC
+ * to the ABTS either after return from this function (assuming any
+ * outstanding op work has been terminated) or upon the callback being
+ * called.
+ *
+ * @target_port: pointer to the (registered) target port the FCP CMD IU
+ *              was received on.
+ * @fcpreq:     pointer to the fcpreq request structure that corresponds
+ *              to the exchange that received the ABTS.
+ */
+void
+nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *target_port,
+			struct nvmefc_tgt_fcp_req *fcpreq)
+{
+	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
+	struct nvmet_fc_tgt_queue *queue;
+	unsigned long flags;
+
+	if (!fod || fod->fcpreq != fcpreq)
+		/* job appears to have already completed, ignore abort */
+		return;
+
+	queue = fod->queue;
+
+	spin_lock_irqsave(&queue->qlock, flags);
+	if (fod->active) {
+		/*
+		 * mark as abort. The abort handler, invoked upon completion
+		 * of any work, will detect the aborted status and do the
+		 * callback.
+		 */
+		spin_lock(&fod->flock);
+		fod->abort = true;
+		fod->aborted = true;
+		spin_unlock(&fod->flock);
+	}
+	spin_unlock_irqrestore(&queue->qlock, flags);
+}
+EXPORT_SYMBOL_GPL(nvmet_fc_rcv_fcp_abort);
+
+
+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 int
+nvmet_fc_add_port(struct nvmet_port *port)
+{
+	struct nvmet_fc_tgtport *tgtport;
+	struct nvmet_fc_port_entry *pe;
+	struct nvmet_fc_traddr traddr = { 0L, 0L };
+	unsigned long flags;
+	int ret;
+
+	/* validate the address info */
+	if ((port->disc_addr.trtype != NVMF_TRTYPE_FC) ||
+	    (port->disc_addr.adrfam != NVMF_ADDR_FAMILY_FC))
+		return -EINVAL;
+
+	/* map the traddr address info to a target port */
+
+	ret = nvme_fc_parse_traddr(&traddr, port->disc_addr.traddr,
+			sizeof(port->disc_addr.traddr));
+	if (ret)
+		return ret;
+
+	pe = kzalloc(sizeof(*pe), GFP_KERNEL);
+	if (!pe)
+		return -ENOMEM;
+
+	ret = -ENXIO;
+	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
+	list_for_each_entry(tgtport, &nvmet_fc_target_list, tgt_list) {
+		if ((tgtport->fc_target_port.node_name == traddr.nn) &&
+		    (tgtport->fc_target_port.port_name == traddr.pn)) {
+			/* a FC port can only be 1 nvmet port id */
+			if (!tgtport->pe) {
+				nvmet_fc_portentry_bind(tgtport, pe, port);
+				ret = 0;
+			} else
+				ret = -EALREADY;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
+
+	if (ret)
+		kfree(pe);
+
+	return ret;
+}
+
+static void
+nvmet_fc_remove_port(struct nvmet_port *port)
+{
+	struct nvmet_fc_port_entry *pe = port->priv;
+
+	nvmet_fc_portentry_unbind(pe);
+
+	kfree(pe);
+}
+
+static void
+nvmet_fc_discovery_chg(struct nvmet_port *port)
+{
+	struct nvmet_fc_port_entry *pe = port->priv;
+	struct nvmet_fc_tgtport *tgtport = pe->tgtport;
+
+	if (tgtport && tgtport->ops->discovery_event)
+		tgtport->ops->discovery_event(&tgtport->fc_target_port);
+}
+
+static const struct nvmet_fabrics_ops nvmet_fc_tgt_fcp_ops = {
+	.owner			= THIS_MODULE,
+	.type			= NVMF_TRTYPE_FC,
+	.msdbd			= 1,
+	.add_port		= nvmet_fc_add_port,
+	.remove_port		= nvmet_fc_remove_port,
+	.queue_response		= nvmet_fc_fcp_nvme_cmd_done,
+	.delete_ctrl		= nvmet_fc_delete_ctrl,
+	.discovery_chg		= nvmet_fc_discovery_chg,
+};
+
+static int __init nvmet_fc_init_module(void)
+{
+	return nvmet_register_transport(&nvmet_fc_tgt_fcp_ops);
+}
+
+static void __exit nvmet_fc_exit_module(void)
+{
+	/* sanity check - all lports should be removed */
+	if (!list_empty(&nvmet_fc_target_list))
+		pr_warn("%s: targetport list not empty\n", __func__);
+
+	nvmet_unregister_transport(&nvmet_fc_tgt_fcp_ops);
+
+	ida_destroy(&nvmet_fc_tgtport_cnt);
+}
+
+module_init(nvmet_fc_init_module);
+module_exit(nvmet_fc_exit_module);
+
+MODULE_LICENSE("GPL v2");