Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A selection of fixes/changes that should make it into this series.
  This contains:

   - NVMe, two merges, containing:
        - pci-e, rdma, and fc fixes
        - Device quirks

   - Fix for a badblocks leak in null_blk

   - bcache fix from Rui Hua for a race condition regression where
     -EINTR was returned to upper layers that didn't expect it.

   - Regression fix for blktrace for a bug introduced in this series.

   - blktrace cleanup for cgroup id.

   - bdi registration error handling.

   - Small series with cleanups for blk-wbt.

   - Various little fixes for typos and the like.

  Nothing earth shattering, most important are the NVMe and bcache fixes"

* 'for-linus' of git://git.kernel.dk/linux-block: (34 commits)
  nvme-pci: fix NULL pointer dereference in nvme_free_host_mem()
  nvme-rdma: fix memory leak during queue allocation
  blktrace: fix trace mutex deadlock
  nvme-rdma: Use mr pool
  nvme-rdma: Check remotely invalidated rkey matches our expected rkey
  nvme-rdma: wait for local invalidation before completing a request
  nvme-rdma: don't complete requests before a send work request has completed
  nvme-rdma: don't suppress send completions
  bcache: check return value of register_shrinker
  bcache: recover data from backing when data is clean
  bcache: Fix building error on MIPS
  bcache: add a comment in journal bucket reading
  nvme-fc: don't use bit masks for set/test_bit() numbers
  blk-wbt: fix comments typo
  blk-wbt: move wbt_clear_stat to common place in wbt_done
  blk-sysfs: remove NULL pointer checking in queue_wb_lat_store
  blk-wbt: remove duplicated setting in wbt_init
  nvme-pci: add quirk for delay before CHK RDY for WDC SN200
  block: remove useless assignment in bio_split
  null_blk: fix dev->badblocks leak
  ...

15 files changed, 249 insertions, 176 deletions

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index c61960deb74a..ccb9975a97fa 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -471,7 +471,6 @@ static void nullb_device_release(struct config_item *item)
 {
 	struct nullb_device *dev = to_nullb_device(item);
 
-	badblocks_exit(&dev->badblocks);
 	null_free_device_storage(dev, false);
 	null_free_dev(dev);
 }
@@ -582,6 +581,10 @@ static struct nullb_device *null_alloc_dev(void)
 
 static void null_free_dev(struct nullb_device *dev)
 {
+	if (!dev)
+		return;
+
+	badblocks_exit(&dev->badblocks);
 	kfree(dev);
 }
 
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index a27d85232ce1..a0cc1bc6d884 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -490,7 +490,7 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned reserve,
 		if (b == -1)
 			goto err;
 
-		k->ptr[i] = PTR(ca->buckets[b].gen,
+		k->ptr[i] = MAKE_PTR(ca->buckets[b].gen,
 				bucket_to_sector(c, b),
 				ca->sb.nr_this_dev);
 
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 11c5503d31dc..81e8dc3dbe5e 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -807,7 +807,10 @@ int bch_btree_cache_alloc(struct cache_set *c)
 	c->shrink.scan_objects = bch_mca_scan;
 	c->shrink.seeks = 4;
 	c->shrink.batch = c->btree_pages * 2;
-	register_shrinker(&c->shrink);
+
+	if (register_shrinker(&c->shrink))
+		pr_warn("bcache: %s: could not register shrinker",
+				__func__);
 
 	return 0;
 }
diff --git a/drivers/md/bcache/extents.c b/drivers/md/bcache/extents.c
index 41c238fc3733..f9d391711595 100644
--- a/drivers/md/bcache/extents.c
+++ b/drivers/md/bcache/extents.c
@@ -585,7 +585,7 @@ static bool bch_extent_merge(struct btree_keys *bk, struct bkey *l, struct bkey
 		return false;
 
 	for (i = 0; i < KEY_PTRS(l); i++)
-		if (l->ptr[i] + PTR(0, KEY_SIZE(l), 0) != r->ptr[i] ||
+		if (l->ptr[i] + MAKE_PTR(0, KEY_SIZE(l), 0) != r->ptr[i] ||
 		    PTR_BUCKET_NR(b->c, l, i) != PTR_BUCKET_NR(b->c, r, i))
 			return false;
 
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 02a98ddb592d..a87165c1d8e5 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -170,6 +170,11 @@ int bch_journal_read(struct cache_set *c, struct list_head *list)
 		 * find a sequence of buckets with valid journal entries
 		 */
 		for (i = 0; i < ca->sb.njournal_buckets; i++) {
+			/*
+			 * We must try the index l with ZERO first for
+			 * correctness due to the scenario that the journal
+			 * bucket is circular buffer which might have wrapped
+			 */
 			l = (i * 2654435769U) % ca->sb.njournal_buckets;
 
 			if (test_bit(l, bitmap))
@@ -507,7 +512,7 @@ static void journal_reclaim(struct cache_set *c)
 			continue;
 
 		ja->cur_idx = next;
-		k->ptr[n++] = PTR(0,
+		k->ptr[n++] = MAKE_PTR(0,
 				  bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
 				  ca->sb.nr_this_dev);
 	}
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 3a7aed7282b2..643c3021624f 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -708,16 +708,15 @@ static void cached_dev_read_error(struct closure *cl)
 {
 	struct search *s = container_of(cl, struct search, cl);
 	struct bio *bio = &s->bio.bio;
-	struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
 
 	/*
-	 * If cache device is dirty (dc->has_dirty is non-zero), then
-	 * recovery a failed read request from cached device may get a
-	 * stale data back. So read failure recovery is only permitted
-	 * when cache device is clean.
+	 * If read request hit dirty data (s->read_dirty_data is true),
+	 * then recovery a failed read request from cached device may
+	 * get a stale data back. So read failure recovery is only
+	 * permitted when read request hit clean data in cache device,
+	 * or when cache read race happened.
 	 */
-	if (s->recoverable &&
-	    (dc && !atomic_read(&dc->has_dirty))) {
+	if (s->recoverable && !s->read_dirty_data) {
 		/* Retry from the backing device: */
 		trace_bcache_read_retry(s->orig_bio);
 
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 25da74d310d1..f837d666cbd4 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1449,19 +1449,19 @@ static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
 	int srcu_idx, ret;
 	u8 data[16] = { 0, };
 
+	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
+	if (unlikely(!ns))
+		return -EWOULDBLOCK;
+
 	put_unaligned_le64(key, &data[0]);
 	put_unaligned_le64(sa_key, &data[8]);
 
 	memset(&c, 0, sizeof(c));
 	c.common.opcode = op;
-	c.common.nsid = cpu_to_le32(head->ns_id);
+	c.common.nsid = cpu_to_le32(ns->head->ns_id);
 	c.common.cdw10[0] = cpu_to_le32(cdw10);
 
-	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
-	if (unlikely(!ns))
-		ret = -EWOULDBLOCK;
-	else
-		ret = nvme_submit_sync_cmd(ns->queue, &c, data, 16);
+	ret = nvme_submit_sync_cmd(ns->queue, &c, data, 16);
 	nvme_put_ns_from_disk(head, srcu_idx);
 	return ret;
 }
@@ -2961,8 +2961,6 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
 
 static void nvme_ns_remove(struct nvme_ns *ns)
 {
-	struct nvme_ns_head *head = ns->head;
-
 	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
 		return;
 
@@ -2980,15 +2978,14 @@ static void nvme_ns_remove(struct nvme_ns *ns)
 
 	mutex_lock(&ns->ctrl->subsys->lock);
 	nvme_mpath_clear_current_path(ns);
-	if (head)
-		list_del_rcu(&ns->siblings);
+	list_del_rcu(&ns->siblings);
 	mutex_unlock(&ns->ctrl->subsys->lock);
 
 	mutex_lock(&ns->ctrl->namespaces_mutex);
 	list_del_init(&ns->list);
 	mutex_unlock(&ns->ctrl->namespaces_mutex);
 
-	synchronize_srcu(&head->srcu);
+	synchronize_srcu(&ns->head->srcu);
 	nvme_put_ns(ns);
 }
 
diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
index 42232e731f19..9ba614953607 100644
--- a/drivers/nvme/host/fabrics.h
+++ b/drivers/nvme/host/fabrics.h
@@ -156,4 +156,34 @@ void nvmf_free_options(struct nvmf_ctrl_options *opts);
 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
 
+static inline blk_status_t nvmf_check_init_req(struct nvme_ctrl *ctrl,
+		struct request *rq)
+{
+	struct nvme_command *cmd = nvme_req(rq)->cmd;
+
+	/*
+	 * We cannot accept any other command until the connect command has
+	 * completed, so only allow connect to pass.
+	 */
+	if (!blk_rq_is_passthrough(rq) ||
+	    cmd->common.opcode != nvme_fabrics_command ||
+	    cmd->fabrics.fctype != nvme_fabrics_type_connect) {
+		/*
+		 * Reconnecting state means transport disruption, which can take
+		 * a long time and even might fail permanently, fail fast to
+		 * give upper layers a chance to failover.
+		 * Deleting state means that the ctrl will never accept commands
+		 * again, fail it permanently.
+		 */
+		if (ctrl->state == NVME_CTRL_RECONNECTING ||
+		    ctrl->state == NVME_CTRL_DELETING) {
+			nvme_req(rq)->status = NVME_SC_ABORT_REQ;
+			return BLK_STS_IOERR;
+		}
+		return BLK_STS_RESOURCE; /* try again later */
+	}
+
+	return BLK_STS_OK;
+}
+
 #endif /* _NVME_FABRICS_H */
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 7ab0be55c7d0..0a8af4daef89 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -31,7 +31,8 @@
 
 
 enum nvme_fc_queue_flags {
-	NVME_FC_Q_CONNECTED = (1 << 0),
+	NVME_FC_Q_CONNECTED = 0,
+	NVME_FC_Q_LIVE,
 };
 
 #define NVMEFC_QUEUE_DELAY	3		/* ms units */
@@ -1927,6 +1928,7 @@ 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
@@ -1934,7 +1936,6 @@ nvme_fc_free_queue(struct nvme_fc_queue *queue)
 	 */
 
 	queue->connection_id = 0;
-	clear_bit(NVME_FC_Q_CONNECTED, &queue->flags);
 }
 
 static void
@@ -2013,6 +2014,8 @@ nvme_fc_connect_io_queues(struct nvme_fc_ctrl *ctrl, u16 qsize)
 		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
 		if (ret)
 			break;
+
+		set_bit(NVME_FC_Q_LIVE, &ctrl->queues[i].flags);
 	}
 
 	return ret;
@@ -2320,6 +2323,14 @@ busy:
 	return BLK_STS_RESOURCE;
 }
 
+static inline blk_status_t nvme_fc_is_ready(struct nvme_fc_queue *queue,
+		struct request *rq)
+{
+	if (unlikely(!test_bit(NVME_FC_Q_LIVE, &queue->flags)))
+		return nvmf_check_init_req(&queue->ctrl->ctrl, rq);
+	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)
@@ -2335,6 +2346,10 @@ nvme_fc_queue_rq(struct blk_mq_hw_ctx *hctx,
 	u32 data_len;
 	blk_status_t ret;
 
+	ret = nvme_fc_is_ready(queue, rq);
+	if (unlikely(ret))
+		return ret;
+
 	ret = nvme_setup_cmd(ns, rq, sqe);
 	if (ret)
 		return ret;
@@ -2727,6 +2742,8 @@ nvme_fc_create_association(struct nvme_fc_ctrl *ctrl)
 	if (ret)
 		goto out_disconnect_admin_queue;
 
+	set_bit(NVME_FC_Q_LIVE, &ctrl->queues[0].flags);
+
 	/*
 	 * Check controller capabilities
 	 *
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 78d92151a904..1218a9fca846 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -131,7 +131,7 @@ static blk_qc_t nvme_ns_head_make_request(struct request_queue *q,
 		bio->bi_opf |= REQ_NVME_MPATH;
 		ret = direct_make_request(bio);
 	} else if (!list_empty_careful(&head->list)) {
-		dev_warn_ratelimited(dev, "no path available - requeing I/O\n");
+		dev_warn_ratelimited(dev, "no path available - requeuing I/O\n");
 
 		spin_lock_irq(&head->requeue_lock);
 		bio_list_add(&head->requeue_list, bio);
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index c0873a68872f..ea1aa5283e8e 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -114,7 +114,7 @@ static inline struct nvme_request *nvme_req(struct request *req)
  * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
  * found empirically.
  */
-#define NVME_QUIRK_DELAY_AMOUNT		2000
+#define NVME_QUIRK_DELAY_AMOUNT		2300
 
 enum nvme_ctrl_state {
 	NVME_CTRL_NEW,
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index a11cfd470089..f5800c3c9082 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1759,6 +1759,7 @@ static void nvme_free_host_mem(struct nvme_dev *dev)
 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
 			dev->host_mem_descs, dev->host_mem_descs_dma);
 	dev->host_mem_descs = NULL;
+	dev->nr_host_mem_descs = 0;
 }
 
 static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
@@ -1787,7 +1788,7 @@ static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
 	if (!bufs)
 		goto out_free_descs;
 
-	for (size = 0; size < preferred; size += len) {
+	for (size = 0; size < preferred && i < max_entries; size += len) {
 		dma_addr_t dma_addr;
 
 		len = min_t(u64, chunk_size, preferred - size);
@@ -2428,7 +2429,7 @@ static int nvme_dev_map(struct nvme_dev *dev)
 	return -ENODEV;
 }
 
-static unsigned long check_dell_samsung_bug(struct pci_dev *pdev)
+static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
 {
 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
 		/*
@@ -2443,6 +2444,14 @@ static unsigned long check_dell_samsung_bug(struct pci_dev *pdev)
 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
 			return NVME_QUIRK_NO_DEEPEST_PS;
+	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
+		/*
+		 * Samsung SSD 960 EVO drops off the PCIe bus after system
+		 * suspend on a Ryzen board, ASUS PRIME B350M-A.
+		 */
+		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
+		    dmi_match(DMI_BOARD_NAME, "PRIME B350M-A"))
+			return NVME_QUIRK_NO_APST;
 	}
 
 	return 0;
@@ -2482,7 +2491,7 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (result)
 		goto unmap;
 
-	quirks |= check_dell_samsung_bug(pdev);
+	quirks |= check_vendor_combination_bug(pdev);
 
 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
 			quirks);
@@ -2665,6 +2674,8 @@ static const struct pci_device_id nvme_id_table[] = {
 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
+	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
+		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 4f9bf2f815c3..37af56596be6 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <rdma/mr_pool.h>
 #include <linux/err.h>
 #include <linux/string.h>
 #include <linux/atomic.h>
@@ -59,6 +60,9 @@ struct nvme_rdma_request {
 	struct nvme_request	req;
 	struct ib_mr		*mr;
 	struct nvme_rdma_qe	sqe;
+	union nvme_result	result;
+	__le16			status;
+	refcount_t		ref;
 	struct ib_sge		sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS];
 	u32			num_sge;
 	int			nents;
@@ -73,11 +77,11 @@ struct nvme_rdma_request {
 enum nvme_rdma_queue_flags {
 	NVME_RDMA_Q_ALLOCATED		= 0,
 	NVME_RDMA_Q_LIVE		= 1,
+	NVME_RDMA_Q_TR_READY		= 2,
 };
 
 struct nvme_rdma_queue {
 	struct nvme_rdma_qe	*rsp_ring;
-	atomic_t		sig_count;
 	int			queue_size;
 	size_t			cmnd_capsule_len;
 	struct nvme_rdma_ctrl	*ctrl;
@@ -258,32 +262,6 @@ static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor)
 	return ret;
 }
 
-static int nvme_rdma_reinit_request(void *data, struct request *rq)
-{
-	struct nvme_rdma_ctrl *ctrl = data;
-	struct nvme_rdma_device *dev = ctrl->device;
-	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
-	int ret = 0;
-
-	if (WARN_ON_ONCE(!req->mr))
-		return 0;
-
-	ib_dereg_mr(req->mr);
-
-	req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
-			ctrl->max_fr_pages);
-	if (IS_ERR(req->mr)) {
-		ret = PTR_ERR(req->mr);
-		req->mr = NULL;
-		goto out;
-	}
-
-	req->mr->need_inval = false;
-
-out:
-	return ret;
-}
-
 static void nvme_rdma_exit_request(struct blk_mq_tag_set *set,
 		struct request *rq, unsigned int hctx_idx)
 {
@@ -293,9 +271,6 @@ static void nvme_rdma_exit_request(struct blk_mq_tag_set *set,
 	struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
 	struct nvme_rdma_device *dev = queue->device;
 
-	if (req->mr)
-		ib_dereg_mr(req->mr);
-
 	nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
 			DMA_TO_DEVICE);
 }
@@ -317,21 +292,9 @@ static int nvme_rdma_init_request(struct blk_mq_tag_set *set,
 	if (ret)
 		return ret;
 
-	req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
-			ctrl->max_fr_pages);
-	if (IS_ERR(req->mr)) {
-		ret = PTR_ERR(req->mr);
-		goto out_free_qe;
-	}
-
 	req->queue = queue;
 
 	return 0;
-
-out_free_qe:
-	nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
-			DMA_TO_DEVICE);
-	return -ENOMEM;
 }
 
 static int nvme_rdma_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
@@ -428,10 +391,23 @@ out_err:
 
 static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
 {
-	struct nvme_rdma_device *dev = queue->device;
-	struct ib_device *ibdev = dev->dev;
+	struct nvme_rdma_device *dev;
+	struct ib_device *ibdev;
 
-	rdma_destroy_qp(queue->cm_id);
+	if (!test_and_clear_bit(NVME_RDMA_Q_TR_READY, &queue->flags))
+		return;
+
+	dev = queue->device;
+	ibdev = dev->dev;
+
+	ib_mr_pool_destroy(queue->qp, &queue->qp->rdma_mrs);
+
+	/*
+	 * The cm_id object might have been destroyed during RDMA connection
+	 * establishment error flow to avoid getting other cma events, thus
+	 * the destruction of the QP shouldn't use rdma_cm API.
+	 */
+	ib_destroy_qp(queue->qp);
 	ib_free_cq(queue->ib_cq);
 
 	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
@@ -440,6 +416,12 @@ static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
 	nvme_rdma_dev_put(dev);
 }
 
+static int nvme_rdma_get_max_fr_pages(struct ib_device *ibdev)
+{
+	return min_t(u32, NVME_RDMA_MAX_SEGMENTS,
+		     ibdev->attrs.max_fast_reg_page_list_len);
+}
+
 static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
 {
 	struct ib_device *ibdev;
@@ -482,8 +464,24 @@ static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
 		goto out_destroy_qp;
 	}
 
+	ret = ib_mr_pool_init(queue->qp, &queue->qp->rdma_mrs,
+			      queue->queue_size,
+			      IB_MR_TYPE_MEM_REG,
+			      nvme_rdma_get_max_fr_pages(ibdev));
+	if (ret) {
+		dev_err(queue->ctrl->ctrl.device,
+			"failed to initialize MR pool sized %d for QID %d\n",
+			queue->queue_size, idx);
+		goto out_destroy_ring;
+	}
+
+	set_bit(NVME_RDMA_Q_TR_READY, &queue->flags);
+
 	return 0;
 
+out_destroy_ring:
+	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
+			    sizeof(struct nvme_completion), DMA_FROM_DEVICE);
 out_destroy_qp:
 	rdma_destroy_qp(queue->cm_id);
 out_destroy_ib_cq:
@@ -510,7 +508,6 @@ static int nvme_rdma_alloc_queue(struct nvme_rdma_ctrl *ctrl,
 		queue->cmnd_capsule_len = sizeof(struct nvme_command);
 
 	queue->queue_size = queue_size;
-	atomic_set(&queue->sig_count, 0);
 
 	queue->cm_id = rdma_create_id(&init_net, nvme_rdma_cm_handler, queue,
 			RDMA_PS_TCP, IB_QPT_RC);
@@ -546,6 +543,7 @@ static int nvme_rdma_alloc_queue(struct nvme_rdma_ctrl *ctrl,
 
 out_destroy_cm_id:
 	rdma_destroy_id(queue->cm_id);
+	nvme_rdma_destroy_queue_ib(queue);
 	return ret;
 }
 
@@ -756,8 +754,7 @@ static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl,
 
 	ctrl->device = ctrl->queues[0].device;
 
-	ctrl->max_fr_pages = min_t(u32, NVME_RDMA_MAX_SEGMENTS,
-		ctrl->device->dev->attrs.max_fast_reg_page_list_len);
+	ctrl->max_fr_pages = nvme_rdma_get_max_fr_pages(ctrl->device->dev);
 
 	if (new) {
 		ctrl->ctrl.admin_tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, true);
@@ -771,10 +768,6 @@ static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl,
 			error = PTR_ERR(ctrl->ctrl.admin_q);
 			goto out_free_tagset;
 		}
-	} else {
-		error = nvme_reinit_tagset(&ctrl->ctrl, ctrl->ctrl.admin_tagset);
-		if (error)
-			goto out_free_queue;
 	}
 
 	error = nvme_rdma_start_queue(ctrl, 0);
@@ -854,10 +847,6 @@ static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new)
 			goto out_free_tag_set;
 		}
 	} else {
-		ret = nvme_reinit_tagset(&ctrl->ctrl, ctrl->ctrl.tagset);
-		if (ret)
-			goto out_free_io_queues;
-
 		blk_mq_update_nr_hw_queues(&ctrl->tag_set,
 			ctrl->ctrl.queue_count - 1);
 	}
@@ -1018,8 +1007,18 @@ static void nvme_rdma_memreg_done(struct ib_cq *cq, struct ib_wc *wc)
 
 static void nvme_rdma_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-	if (unlikely(wc->status != IB_WC_SUCCESS))
+	struct nvme_rdma_request *req =
+		container_of(wc->wr_cqe, struct nvme_rdma_request, reg_cqe);
+	struct request *rq = blk_mq_rq_from_pdu(req);
+
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
 		nvme_rdma_wr_error(cq, wc, "LOCAL_INV");
+		return;
+	}
+
+	if (refcount_dec_and_test(&req->ref))
+		nvme_end_request(rq, req->status, req->result);
+
 }
 
 static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
@@ -1030,7 +1029,7 @@ static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
 		.opcode		    = IB_WR_LOCAL_INV,
 		.next		    = NULL,
 		.num_sge	    = 0,
-		.send_flags	    = 0,
+		.send_flags	    = IB_SEND_SIGNALED,
 		.ex.invalidate_rkey = req->mr->rkey,
 	};
 
@@ -1044,22 +1043,15 @@ static void nvme_rdma_unmap_data(struct nvme_rdma_queue *queue,
 		struct request *rq)
 {
 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
-	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
 	struct nvme_rdma_device *dev = queue->device;
 	struct ib_device *ibdev = dev->dev;
-	int res;
 
 	if (!blk_rq_bytes(rq))
 		return;
 
-	if (req->mr->need_inval && test_bit(NVME_RDMA_Q_LIVE, &req->queue->flags)) {
-		res = nvme_rdma_inv_rkey(queue, req);
-		if (unlikely(res < 0)) {
-			dev_err(ctrl->ctrl.device,
-				"Queueing INV WR for rkey %#x failed (%d)\n",
-				req->mr->rkey, res);
-			nvme_rdma_error_recovery(queue->ctrl);
-		}
+	if (req->mr) {
+		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
+		req->mr = NULL;
 	}
 
 	ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
@@ -1118,12 +1110,18 @@ static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
 	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
 	int nr;
 
+	req->mr = ib_mr_pool_get(queue->qp, &queue->qp->rdma_mrs);
+	if (WARN_ON_ONCE(!req->mr))
+		return -EAGAIN;
+
 	/*
 	 * Align the MR to a 4K page size to match the ctrl page size and
 	 * the block virtual boundary.
 	 */
 	nr = ib_map_mr_sg(req->mr, req->sg_table.sgl, count, NULL, SZ_4K);
 	if (unlikely(nr < count)) {
+		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
+		req->mr = NULL;
 		if (nr < 0)
 			return nr;
 		return -EINVAL;
@@ -1142,8 +1140,6 @@ static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
 			     IB_ACCESS_REMOTE_READ |
 			     IB_ACCESS_REMOTE_WRITE;
 
-	req->mr->need_inval = true;
-
 	sg->addr = cpu_to_le64(req->mr->iova);
 	put_unaligned_le24(req->mr->length, sg->length);
 	put_unaligned_le32(req->mr->rkey, sg->key);
@@ -1163,7 +1159,7 @@ static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
 
 	req->num_sge = 1;
 	req->inline_data = false;
-	req->mr->need_inval = false;
+	refcount_set(&req->ref, 2); /* send and recv completions */
 
 	c->common.flags |= NVME_CMD_SGL_METABUF;
 
@@ -1200,25 +1196,24 @@ static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
 
 static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-	if (unlikely(wc->status != IB_WC_SUCCESS))
-		nvme_rdma_wr_error(cq, wc, "SEND");
-}
+	struct nvme_rdma_qe *qe =
+		container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
+	struct nvme_rdma_request *req =
+		container_of(qe, struct nvme_rdma_request, sqe);
+	struct request *rq = blk_mq_rq_from_pdu(req);
 
-/*
- * We want to signal completion at least every queue depth/2.  This returns the
- * largest power of two that is not above half of (queue size + 1) to optimize
- * (avoid divisions).
- */
-static inline bool nvme_rdma_queue_sig_limit(struct nvme_rdma_queue *queue)
-{
-	int limit = 1 << ilog2((queue->queue_size + 1) / 2);
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
+		nvme_rdma_wr_error(cq, wc, "SEND");
+		return;
+	}
 
-	return (atomic_inc_return(&queue->sig_count) & (limit - 1)) == 0;
+	if (refcount_dec_and_test(&req->ref))
+		nvme_end_request(rq, req->status, req->result);
 }
 
 static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
 		struct nvme_rdma_qe *qe, struct ib_sge *sge, u32 num_sge,
-		struct ib_send_wr *first, bool flush)
+		struct ib_send_wr *first)
 {
 	struct ib_send_wr wr, *bad_wr;
 	int ret;
@@ -1227,31 +1222,12 @@ static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
 	sge->length = sizeof(struct nvme_command),
 	sge->lkey   = queue->device->pd->local_dma_lkey;
 
-	qe->cqe.done = nvme_rdma_send_done;
-
 	wr.next       = NULL;
 	wr.wr_cqe     = &qe->cqe;
 	wr.sg_list    = sge;
 	wr.num_sge    = num_sge;
 	wr.opcode     = IB_WR_SEND;
-	wr.send_flags = 0;
-
-	/*
-	 * Unsignalled send completions are another giant desaster in the
-	 * IB Verbs spec:  If we don't regularly post signalled sends
-	 * the send queue will fill up and only a QP reset will rescue us.
-	 * Would have been way to obvious to handle this in hardware or
-	 * at least the RDMA stack..
-	 *
-	 * Always signal the flushes. The magic request used for the flush
-	 * sequencer is not allocated in our driver's tagset and it's
-	 * triggered to be freed by blk_cleanup_queue(). So we need to
-	 * always mark it as signaled to ensure that the "wr_cqe", which is
-	 * embedded in request's payload, is not freed when __ib_process_cq()
-	 * calls wr_cqe->done().
-	 */
-	if (nvme_rdma_queue_sig_limit(queue) || flush)
-		wr.send_flags |= IB_SEND_SIGNALED;
+	wr.send_flags = IB_SEND_SIGNALED;
 
 	if (first)
 		first->next = &wr;
@@ -1301,6 +1277,12 @@ static struct blk_mq_tags *nvme_rdma_tagset(struct nvme_rdma_queue *queue)
 	return queue->ctrl->tag_set.tags[queue_idx - 1];
 }
 
+static void nvme_rdma_async_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	if (unlikely(wc->status != IB_WC_SUCCESS))
+		nvme_rdma_wr_error(cq, wc, "ASYNC");
+}
+
 static void nvme_rdma_submit_async_event(struct nvme_ctrl *arg)
 {
 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(arg);
@@ -1319,10 +1301,12 @@ static void nvme_rdma_submit_async_event(struct nvme_ctrl *arg)
 	cmd->common.flags |= NVME_CMD_SGL_METABUF;
 	nvme_rdma_set_sg_null(cmd);
 
+	sqe->cqe.done = nvme_rdma_async_done;
+
 	ib_dma_sync_single_for_device(dev, sqe->dma, sizeof(*cmd),
 			DMA_TO_DEVICE);
 
-	ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL, false);
+	ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL);
 	WARN_ON_ONCE(ret);
 }
 
@@ -1343,14 +1327,34 @@ static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue,
 	}
 	req = blk_mq_rq_to_pdu(rq);
 
-	if (rq->tag == tag)
-		ret = 1;
+	req->status = cqe->status;
+	req->result = cqe->result;
 
-	if ((wc->wc_flags & IB_WC_WITH_INVALIDATE) &&
-	    wc->ex.invalidate_rkey == req->mr->rkey)
-		req->mr->need_inval = false;
+	if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
+		if (unlikely(wc->ex.invalidate_rkey != req->mr->rkey)) {
+			dev_err(queue->ctrl->ctrl.device,
+				"Bogus remote invalidation for rkey %#x\n",
+				req->mr->rkey);
+			nvme_rdma_error_recovery(queue->ctrl);
+		}
+	} else if (req->mr) {
+		ret = nvme_rdma_inv_rkey(queue, req);
+		if (unlikely(ret < 0)) {
+			dev_err(queue->ctrl->ctrl.device,
+				"Queueing INV WR for rkey %#x failed (%d)\n",
+				req->mr->rkey, ret);
+			nvme_rdma_error_recovery(queue->ctrl);
+		}
+		/* the local invalidation completion will end the request */
+		return 0;
+	}
+
+	if (refcount_dec_and_test(&req->ref)) {
+		if (rq->tag == tag)
+			ret = 1;
+		nvme_end_request(rq, req->status, req->result);
+	}
 
-	nvme_end_request(rq, cqe->status, cqe->result);
 	return ret;
 }
 
@@ -1591,31 +1595,11 @@ nvme_rdma_timeout(struct request *rq, bool reserved)
  * We cannot accept any other command until the Connect command has completed.
  */
 static inline blk_status_t
-nvme_rdma_queue_is_ready(struct nvme_rdma_queue *queue, struct request *rq)
-{
-	if (unlikely(!test_bit(NVME_RDMA_Q_LIVE, &queue->flags))) {
-		struct nvme_command *cmd = nvme_req(rq)->cmd;
-
-		if (!blk_rq_is_passthrough(rq) ||
-		    cmd->common.opcode != nvme_fabrics_command ||
-		    cmd->fabrics.fctype != nvme_fabrics_type_connect) {
-			/*
-			 * reconnecting state means transport disruption, which
-			 * can take a long time and even might fail permanently,
-			 * fail fast to give upper layers a chance to failover.
-			 * deleting state means that the ctrl will never accept
-			 * commands again, fail it permanently.
-			 */
-			if (queue->ctrl->ctrl.state == NVME_CTRL_RECONNECTING ||
-			    queue->ctrl->ctrl.state == NVME_CTRL_DELETING) {
-				nvme_req(rq)->status = NVME_SC_ABORT_REQ;
-				return BLK_STS_IOERR;
-			}
-			return BLK_STS_RESOURCE; /* try again later */
-		}
-	}
-
-	return 0;
+nvme_rdma_is_ready(struct nvme_rdma_queue *queue, struct request *rq)
+{
+	if (unlikely(!test_bit(NVME_RDMA_Q_LIVE, &queue->flags)))
+		return nvmf_check_init_req(&queue->ctrl->ctrl, rq);
+	return BLK_STS_OK;
 }
 
 static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
@@ -1627,14 +1611,13 @@ static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 	struct nvme_rdma_qe *sqe = &req->sqe;
 	struct nvme_command *c = sqe->data;
-	bool flush = false;
 	struct ib_device *dev;
 	blk_status_t ret;
 	int err;
 
 	WARN_ON_ONCE(rq->tag < 0);
 
-	ret = nvme_rdma_queue_is_ready(queue, rq);
+	ret = nvme_rdma_is_ready(queue, rq);
 	if (unlikely(ret))
 		return ret;
 
@@ -1656,13 +1639,13 @@ static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
 		goto err;
 	}
 
+	sqe->cqe.done = nvme_rdma_send_done;
+
 	ib_dma_sync_single_for_device(dev, sqe->dma,
 			sizeof(struct nvme_command), DMA_TO_DEVICE);
 
-	if (req_op(rq) == REQ_OP_FLUSH)
-		flush = true;
 	err = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
-			req->mr->need_inval ? &req->reg_wr.wr : NULL, flush);
+			req->mr ? &req->reg_wr.wr : NULL);
 	if (unlikely(err)) {
 		nvme_rdma_unmap_data(queue, rq);
 		goto err;
@@ -1810,7 +1793,6 @@ static const struct nvme_ctrl_ops nvme_rdma_ctrl_ops = {
 	.submit_async_event	= nvme_rdma_submit_async_event,
 	.delete_ctrl		= nvme_rdma_delete_ctrl,
 	.get_address		= nvmf_get_address,
-	.reinit_request		= nvme_rdma_reinit_request,
 };
 
 static inline bool
diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
index 664d3013f68f..5fd86039e353 100644
--- a/drivers/nvme/target/fc.c
+++ b/drivers/nvme/target/fc.c
@@ -533,15 +533,15 @@ nvmet_fc_free_fcp_iod(struct nvmet_fc_tgt_queue *queue,
 
 	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);
-
-		/* Release reference taken at queue lookup and fod allocation */
-		nvmet_fc_tgt_q_put(queue);
 		return;
 	}
 
@@ -760,6 +760,9 @@ nvmet_fc_delete_target_queue(struct nvmet_fc_tgt_queue *queue)
 		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);
diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index 96d390416789..1e21b286f299 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -52,10 +52,15 @@ static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl)
 	return container_of(ctrl, struct nvme_loop_ctrl, ctrl);
 }
 
+enum nvme_loop_queue_flags {
+	NVME_LOOP_Q_LIVE	= 0,
+};
+
 struct nvme_loop_queue {
 	struct nvmet_cq		nvme_cq;
 	struct nvmet_sq		nvme_sq;
 	struct nvme_loop_ctrl	*ctrl;
+	unsigned long		flags;
 };
 
 static struct nvmet_port *nvmet_loop_port;
@@ -144,6 +149,14 @@ nvme_loop_timeout(struct request *rq, bool reserved)
 	return BLK_EH_HANDLED;
 }
 
+static inline blk_status_t nvme_loop_is_ready(struct nvme_loop_queue *queue,
+		struct request *rq)
+{
+	if (unlikely(!test_bit(NVME_LOOP_Q_LIVE, &queue->flags)))
+		return nvmf_check_init_req(&queue->ctrl->ctrl, rq);
+	return BLK_STS_OK;
+}
+
 static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx,
 		const struct blk_mq_queue_data *bd)
 {
@@ -153,6 +166,10 @@ static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx,
 	struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
 	blk_status_t ret;
 
+	ret = nvme_loop_is_ready(queue, req);
+	if (unlikely(ret))
+		return ret;
+
 	ret = nvme_setup_cmd(ns, req, &iod->cmd);
 	if (ret)
 		return ret;
@@ -267,6 +284,7 @@ static const struct blk_mq_ops nvme_loop_admin_mq_ops = {
 
 static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl)
 {
+	clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
 	nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
 	blk_cleanup_queue(ctrl->ctrl.admin_q);
 	blk_mq_free_tag_set(&ctrl->admin_tag_set);
@@ -297,8 +315,10 @@ static void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl)
 {
 	int i;
 
-	for (i = 1; i < ctrl->ctrl.queue_count; i++)
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
 		nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
+	}
 }
 
 static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl)
@@ -338,6 +358,7 @@ static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl)
 		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
 		if (ret)
 			return ret;
+		set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
 	}
 
 	return 0;
@@ -380,6 +401,8 @@ static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
 	if (error)
 		goto out_cleanup_queue;
 
+	set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
+
 	error = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->ctrl.cap);
 	if (error) {
 		dev_err(ctrl->ctrl.device,