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

Pull block fixes from Jens Axboe:

 - an NVMe fix from Gabriel, fixing a suspend/resume issue on some
   setups

 - addition of a few missing entries in the block queue sysfs
   documentation, from Joe

 - a fix for a sparse shadow warning for the bvec iterator, from
   Johannes

 - a writeback deadlock involving raid issuing barriers, and not
   flushing the plug when we wakeup the flusher threads.  From
   Konstantin

 - a set of patches for the NVMe target/loop/rdma code, from Roland and
   Sagi

* 'for-linus' of git://git.kernel.dk/linux-block:
  bvec: avoid variable shadowing warning
  doc: update block/queue-sysfs.txt entries
  nvme: Suspend all queues before deletion
  mm, writeback: flush plugged IO in wakeup_flusher_threads()
  nvme-rdma: Remove unused includes
  nvme-rdma: start async event handler after reconnecting to a controller
  nvmet: Fix controller serial number inconsistency
  nvmet-rdma: Don't use the inline buffer in order to avoid allocation for small reads
  nvmet-rdma: Correctly handle RDMA device hot removal
  nvme-rdma: Make sure to shutdown the controller if we can
  nvme-loop: Remove duplicate call to nvme_remove_namespaces
  nvme-rdma: Free the I/O tags when we delete the controller
  nvme-rdma: Remove duplicate call to nvme_remove_namespaces
  nvme-rdma: Fix device removal handling
  nvme-rdma: Queue ns scanning after a sucessful reconnection
  nvme-rdma: Don't leak uninitialized memory in connect request private data

7 files changed, 134 insertions, 84 deletions

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index d7c33f9361aa..8dcf5a960951 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1543,15 +1543,10 @@ static void nvme_disable_io_queues(struct nvme_dev *dev)
 		reinit_completion(&dev->ioq_wait);
  retry:
 		timeout = ADMIN_TIMEOUT;
-		for (; i > 0; i--) {
-			struct nvme_queue *nvmeq = dev->queues[i];
-
-			if (!pass)
-				nvme_suspend_queue(nvmeq);
-			if (nvme_delete_queue(nvmeq, opcode))
+		for (; i > 0; i--, sent++)
+			if (nvme_delete_queue(dev->queues[i], opcode))
 				break;
-			++sent;
-		}
+
 		while (sent--) {
 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
 			if (timeout == 0)
@@ -1693,11 +1688,12 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
 		nvme_stop_queues(&dev->ctrl);
 		csts = readl(dev->bar + NVME_REG_CSTS);
 	}
+
+	for (i = dev->queue_count - 1; i > 0; i--)
+		nvme_suspend_queue(dev->queues[i]);
+
 	if (csts & NVME_CSTS_CFS || !(csts & NVME_CSTS_RDY)) {
-		for (i = dev->queue_count - 1; i >= 0; i--) {
-			struct nvme_queue *nvmeq = dev->queues[i];
-			nvme_suspend_queue(nvmeq);
-		}
+		nvme_suspend_queue(dev->queues[0]);
 	} else {
 		nvme_disable_io_queues(dev);
 		nvme_disable_admin_queue(dev, shutdown);
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 3e3ce2b0424e..8d2875b4c56d 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -12,13 +12,11 @@
  * more details.
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/string.h>
-#include <linux/jiffies.h>
 #include <linux/atomic.h>
 #include <linux/blk-mq.h>
 #include <linux/types.h>
@@ -26,7 +24,6 @@
 #include <linux/mutex.h>
 #include <linux/scatterlist.h>
 #include <linux/nvme.h>
-#include <linux/t10-pi.h>
 #include <asm/unaligned.h>
 
 #include <rdma/ib_verbs.h>
@@ -169,7 +166,6 @@ MODULE_PARM_DESC(register_always,
 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
 		struct rdma_cm_event *event);
 static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
-static int __nvme_rdma_del_ctrl(struct nvme_rdma_ctrl *ctrl);
 
 /* XXX: really should move to a generic header sooner or later.. */
 static inline void put_unaligned_le24(u32 val, u8 *p)
@@ -687,11 +683,6 @@ static void nvme_rdma_free_ctrl(struct nvme_ctrl *nctrl)
 	list_del(&ctrl->list);
 	mutex_unlock(&nvme_rdma_ctrl_mutex);
 
-	if (ctrl->ctrl.tagset) {
-		blk_cleanup_queue(ctrl->ctrl.connect_q);
-		blk_mq_free_tag_set(&ctrl->tag_set);
-		nvme_rdma_dev_put(ctrl->device);
-	}
 	kfree(ctrl->queues);
 	nvmf_free_options(nctrl->opts);
 free_ctrl:
@@ -748,8 +739,11 @@ static void nvme_rdma_reconnect_ctrl_work(struct work_struct *work)
 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
 	WARN_ON_ONCE(!changed);
 
-	if (ctrl->queue_count > 1)
+	if (ctrl->queue_count > 1) {
 		nvme_start_queues(&ctrl->ctrl);
+		nvme_queue_scan(&ctrl->ctrl);
+		nvme_queue_async_events(&ctrl->ctrl);
+	}
 
 	dev_info(ctrl->ctrl.device, "Successfully reconnected\n");
 
@@ -1269,7 +1263,7 @@ static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
 {
 	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
 	struct rdma_conn_param param = { };
-	struct nvme_rdma_cm_req priv;
+	struct nvme_rdma_cm_req priv = { };
 	int ret;
 
 	param.qp_num = queue->qp->qp_num;
@@ -1318,37 +1312,39 @@ out_destroy_queue_ib:
  * that caught the event. Since we hold the callout until the controller
  * deletion is completed, we'll deadlock if the controller deletion will
  * call rdma_destroy_id on this queue's cm_id. Thus, we claim ownership
- * of destroying this queue before-hand, destroy the queue resources
- * after the controller deletion completed with the exception of destroying
- * the cm_id implicitely by returning a non-zero rc to the callout.
+ * of destroying this queue before-hand, destroy the queue resources,
+ * then queue the controller deletion which won't destroy this queue and
+ * we destroy the cm_id implicitely by returning a non-zero rc to the callout.
  */
 static int nvme_rdma_device_unplug(struct nvme_rdma_queue *queue)
 {
 	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
-	int ret, ctrl_deleted = 0;
+	int ret;
 
-	/* First disable the queue so ctrl delete won't free it */
-	if (!test_and_clear_bit(NVME_RDMA_Q_CONNECTED, &queue->flags))
-		goto out;
+	/* Own the controller deletion */
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
+		return 0;
 
-	/* delete the controller */
-	ret = __nvme_rdma_del_ctrl(ctrl);
-	if (!ret) {
-		dev_warn(ctrl->ctrl.device,
-			"Got rdma device removal event, deleting ctrl\n");
-		flush_work(&ctrl->delete_work);
+	dev_warn(ctrl->ctrl.device,
+		"Got rdma device removal event, deleting ctrl\n");
 
-		/* Return non-zero so the cm_id will destroy implicitly */
-		ctrl_deleted = 1;
+	/* Get rid of reconnect work if its running */
+	cancel_delayed_work_sync(&ctrl->reconnect_work);
 
+	/* Disable the queue so ctrl delete won't free it */
+	if (test_and_clear_bit(NVME_RDMA_Q_CONNECTED, &queue->flags)) {
 		/* Free this queue ourselves */
-		rdma_disconnect(queue->cm_id);
-		ib_drain_qp(queue->qp);
+		nvme_rdma_stop_queue(queue);
 		nvme_rdma_destroy_queue_ib(queue);
+
+		/* Return non-zero so the cm_id will destroy implicitly */
+		ret = 1;
 	}
 
-out:
-	return ctrl_deleted;
+	/* Queue controller deletion */
+	queue_work(nvme_rdma_wq, &ctrl->delete_work);
+	flush_work(&ctrl->delete_work);
+	return ret;
 }
 
 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
@@ -1648,7 +1644,7 @@ static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl)
 		nvme_rdma_free_io_queues(ctrl);
 	}
 
-	if (ctrl->ctrl.state == NVME_CTRL_LIVE)
+	if (test_bit(NVME_RDMA_Q_CONNECTED, &ctrl->queues[0].flags))
 		nvme_shutdown_ctrl(&ctrl->ctrl);
 
 	blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
@@ -1657,15 +1653,27 @@ static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl)
 	nvme_rdma_destroy_admin_queue(ctrl);
 }
 
+static void __nvme_rdma_remove_ctrl(struct nvme_rdma_ctrl *ctrl, bool shutdown)
+{
+	nvme_uninit_ctrl(&ctrl->ctrl);
+	if (shutdown)
+		nvme_rdma_shutdown_ctrl(ctrl);
+
+	if (ctrl->ctrl.tagset) {
+		blk_cleanup_queue(ctrl->ctrl.connect_q);
+		blk_mq_free_tag_set(&ctrl->tag_set);
+		nvme_rdma_dev_put(ctrl->device);
+	}
+
+	nvme_put_ctrl(&ctrl->ctrl);
+}
+
 static void nvme_rdma_del_ctrl_work(struct work_struct *work)
 {
 	struct nvme_rdma_ctrl *ctrl = container_of(work,
 				struct nvme_rdma_ctrl, delete_work);
 
-	nvme_remove_namespaces(&ctrl->ctrl);
-	nvme_rdma_shutdown_ctrl(ctrl);
-	nvme_uninit_ctrl(&ctrl->ctrl);
-	nvme_put_ctrl(&ctrl->ctrl);
+	__nvme_rdma_remove_ctrl(ctrl, true);
 }
 
 static int __nvme_rdma_del_ctrl(struct nvme_rdma_ctrl *ctrl)
@@ -1698,9 +1706,7 @@ static void nvme_rdma_remove_ctrl_work(struct work_struct *work)
 	struct nvme_rdma_ctrl *ctrl = container_of(work,
 				struct nvme_rdma_ctrl, delete_work);
 
-	nvme_remove_namespaces(&ctrl->ctrl);
-	nvme_uninit_ctrl(&ctrl->ctrl);
-	nvme_put_ctrl(&ctrl->ctrl);
+	__nvme_rdma_remove_ctrl(ctrl, false);
 }
 
 static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
@@ -1739,6 +1745,7 @@ static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
 	if (ctrl->queue_count > 1) {
 		nvme_start_queues(&ctrl->ctrl);
 		nvme_queue_scan(&ctrl->ctrl);
+		nvme_queue_async_events(&ctrl->ctrl);
 	}
 
 	return;
diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 2fac17a5ad53..47c564b5a289 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -13,7 +13,6 @@
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/module.h>
-#include <linux/random.h>
 #include <generated/utsrelease.h>
 #include "nvmet.h"
 
@@ -83,7 +82,6 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
 {
 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
 	struct nvme_id_ctrl *id;
-	u64 serial;
 	u16 status = 0;
 
 	id = kzalloc(sizeof(*id), GFP_KERNEL);
@@ -96,10 +94,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
 	id->vid = 0;
 	id->ssvid = 0;
 
-	/* generate a random serial number as our controllers are ephemeral: */
-	get_random_bytes(&serial, sizeof(serial));
 	memset(id->sn, ' ', sizeof(id->sn));
-	snprintf(id->sn, sizeof(id->sn), "%llx", serial);
+	snprintf(id->sn, sizeof(id->sn), "%llx", ctrl->serial);
 
 	memset(id->mn, ' ', sizeof(id->mn));
 	strncpy((char *)id->mn, "Linux", sizeof(id->mn));
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 8a891ca53367..6559d5afa7bf 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -13,6 +13,7 @@
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/module.h>
+#include <linux/random.h>
 #include "nvmet.h"
 
 static struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
@@ -728,6 +729,9 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
 	memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
 	memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
 
+	/* generate a random serial number as our controllers are ephemeral: */
+	get_random_bytes(&ctrl->serial, sizeof(ctrl->serial));
+
 	kref_init(&ctrl->ref);
 	ctrl->subsys = subsys;
 
diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index 94e782987cc9..7affd40a6b33 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -414,9 +414,8 @@ static void nvme_loop_del_ctrl_work(struct work_struct *work)
 	struct nvme_loop_ctrl *ctrl = container_of(work,
 				struct nvme_loop_ctrl, delete_work);
 
-	nvme_remove_namespaces(&ctrl->ctrl);
-	nvme_loop_shutdown_ctrl(ctrl);
 	nvme_uninit_ctrl(&ctrl->ctrl);
+	nvme_loop_shutdown_ctrl(ctrl);
 	nvme_put_ctrl(&ctrl->ctrl);
 }
 
@@ -501,7 +500,6 @@ out_free_queues:
 	nvme_loop_destroy_admin_queue(ctrl);
 out_disable:
 	dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
-	nvme_remove_namespaces(&ctrl->ctrl);
 	nvme_uninit_ctrl(&ctrl->ctrl);
 	nvme_put_ctrl(&ctrl->ctrl);
 }
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 57dd6d834c28..76b6eedccaf9 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -113,6 +113,7 @@ struct nvmet_ctrl {
 
 	struct mutex		lock;
 	u64			cap;
+	u64			serial;
 	u32			cc;
 	u32			csts;
 
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index e06d504bdf0c..b4d648536c3e 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -77,6 +77,7 @@ enum nvmet_rdma_queue_state {
 	NVMET_RDMA_Q_CONNECTING,
 	NVMET_RDMA_Q_LIVE,
 	NVMET_RDMA_Q_DISCONNECTING,
+	NVMET_RDMA_IN_DEVICE_REMOVAL,
 };
 
 struct nvmet_rdma_queue {
@@ -615,15 +616,10 @@ static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
 	if (!len)
 		return 0;
 
-	/* use the already allocated data buffer if possible */
-	if (len <= NVMET_RDMA_INLINE_DATA_SIZE && rsp->queue->host_qid) {
-		nvmet_rdma_use_inline_sg(rsp, len, 0);
-	} else {
-		status = nvmet_rdma_alloc_sgl(&rsp->req.sg, &rsp->req.sg_cnt,
-				len);
-		if (status)
-			return status;
-	}
+	status = nvmet_rdma_alloc_sgl(&rsp->req.sg, &rsp->req.sg_cnt,
+			len);
+	if (status)
+		return status;
 
 	ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num,
 			rsp->req.sg, rsp->req.sg_cnt, 0, addr, key,
@@ -984,7 +980,10 @@ static void nvmet_rdma_release_queue_work(struct work_struct *w)
 	struct nvmet_rdma_device *dev = queue->dev;
 
 	nvmet_rdma_free_queue(queue);
-	rdma_destroy_id(cm_id);
+
+	if (queue->state != NVMET_RDMA_IN_DEVICE_REMOVAL)
+		rdma_destroy_id(cm_id);
+
 	kref_put(&dev->ref, nvmet_rdma_free_dev);
 }
 
@@ -1233,8 +1232,9 @@ static void __nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
 	switch (queue->state) {
 	case NVMET_RDMA_Q_CONNECTING:
 	case NVMET_RDMA_Q_LIVE:
-		disconnect = true;
 		queue->state = NVMET_RDMA_Q_DISCONNECTING;
+	case NVMET_RDMA_IN_DEVICE_REMOVAL:
+		disconnect = true;
 		break;
 	case NVMET_RDMA_Q_DISCONNECTING:
 		break;
@@ -1272,6 +1272,62 @@ static void nvmet_rdma_queue_connect_fail(struct rdma_cm_id *cm_id,
 	schedule_work(&queue->release_work);
 }
 
+/**
+ * nvme_rdma_device_removal() - Handle RDMA device removal
+ * @queue:      nvmet rdma queue (cm id qp_context)
+ * @addr:	nvmet address (cm_id context)
+ *
+ * DEVICE_REMOVAL event notifies us that the RDMA device is about
+ * to unplug so we should take care of destroying our RDMA resources.
+ * This event will be generated for each allocated cm_id.
+ *
+ * Note that this event can be generated on a normal queue cm_id
+ * and/or a device bound listener cm_id (where in this case
+ * queue will be null).
+ *
+ * we claim ownership on destroying the cm_id. For queues we move
+ * the queue state to NVMET_RDMA_IN_DEVICE_REMOVAL and for port
+ * we nullify the priv to prevent double cm_id destruction and destroying
+ * the cm_id implicitely by returning a non-zero rc to the callout.
+ */
+static int nvmet_rdma_device_removal(struct rdma_cm_id *cm_id,
+		struct nvmet_rdma_queue *queue)
+{
+	unsigned long flags;
+
+	if (!queue) {
+		struct nvmet_port *port = cm_id->context;
+
+		/*
+		 * This is a listener cm_id. Make sure that
+		 * future remove_port won't invoke a double
+		 * cm_id destroy. use atomic xchg to make sure
+		 * we don't compete with remove_port.
+		 */
+		if (xchg(&port->priv, NULL) != cm_id)
+			return 0;
+	} else {
+		/*
+		 * This is a queue cm_id. Make sure that
+		 * release queue will not destroy the cm_id
+		 * and schedule all ctrl queues removal (only
+		 * if the queue is not disconnecting already).
+		 */
+		spin_lock_irqsave(&queue->state_lock, flags);
+		if (queue->state != NVMET_RDMA_Q_DISCONNECTING)
+			queue->state = NVMET_RDMA_IN_DEVICE_REMOVAL;
+		spin_unlock_irqrestore(&queue->state_lock, flags);
+		nvmet_rdma_queue_disconnect(queue);
+		flush_scheduled_work();
+	}
+
+	/*
+	 * We need to return 1 so that the core will destroy
+	 * it's own ID.  What a great API design..
+	 */
+	return 1;
+}
+
 static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id,
 		struct rdma_cm_event *event)
 {
@@ -1294,20 +1350,11 @@ static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id,
 		break;
 	case RDMA_CM_EVENT_ADDR_CHANGE:
 	case RDMA_CM_EVENT_DISCONNECTED:
-	case RDMA_CM_EVENT_DEVICE_REMOVAL:
 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
-		/*
-		 * We can get the device removal callback even for a
-		 * CM ID that we aren't actually using.  In that case
-		 * the context pointer is NULL, so we shouldn't try
-		 * to disconnect a non-existing queue.  But we also
-		 * need to return 1 so that the core will destroy
-		 * it's own ID.  What a great API design..
-		 */
-		if (queue)
-			nvmet_rdma_queue_disconnect(queue);
-		else
-			ret = 1;
+		nvmet_rdma_queue_disconnect(queue);
+		break;
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+		ret = nvmet_rdma_device_removal(cm_id, queue);
 		break;
 	case RDMA_CM_EVENT_REJECTED:
 	case RDMA_CM_EVENT_UNREACHABLE:
@@ -1396,9 +1443,10 @@ out_destroy_id:
 
 static void nvmet_rdma_remove_port(struct nvmet_port *port)
 {
-	struct rdma_cm_id *cm_id = port->priv;
+	struct rdma_cm_id *cm_id = xchg(&port->priv, NULL);
 
-	rdma_destroy_id(cm_id);
+	if (cm_id)
+		rdma_destroy_id(cm_id);
 }
 
 static struct nvmet_fabrics_ops nvmet_rdma_ops = {