1 files changed, 99 insertions, 44 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 2cca9cffc63f..c35b6de4ca64 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -86,10 +86,8 @@ scsi_set_blocked(struct scsi_cmnd *cmd, int reason)
 static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd)
 {
 	struct scsi_device *sdev = cmd->device;
-	struct request_queue *q = cmd->request->q;
 
-	blk_mq_requeue_request(cmd->request);
-	blk_mq_kick_requeue_list(q);
+	blk_mq_requeue_request(cmd->request, true);
 	put_device(&sdev->sdev_gendev);
 }
 
@@ -163,26 +161,11 @@ void scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
 {
 	__scsi_queue_insert(cmd, reason, 1);
 }
-/**
- * scsi_execute - insert request and wait for the result
- * @sdev:	scsi device
- * @cmd:	scsi command
- * @data_direction: data direction
- * @buffer:	data buffer
- * @bufflen:	len of buffer
- * @sense:	optional sense buffer
- * @timeout:	request timeout in seconds
- * @retries:	number of times to retry request
- * @flags:	or into request flags;
- * @resid:	optional residual length
- *
- * returns the req->errors value which is the scsi_cmnd result
- * field.
- */
-int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
+
+static int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 		 int data_direction, void *buffer, unsigned bufflen,
 		 unsigned char *sense, int timeout, int retries, u64 flags,
-		 int *resid)
+		 req_flags_t rq_flags, int *resid)
 {
 	struct request *req;
 	int write = (data_direction == DMA_TO_DEVICE);
@@ -203,7 +186,8 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 	req->sense_len = 0;
 	req->retries = retries;
 	req->timeout = timeout;
-	req->cmd_flags |= flags | REQ_QUIET | REQ_PREEMPT;
+	req->cmd_flags |= flags;
+	req->rq_flags |= rq_flags | RQF_QUIET | RQF_PREEMPT;
 
 	/*
 	 * head injection *required* here otherwise quiesce won't work
@@ -227,12 +211,37 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 
 	return ret;
 }
+
+/**
+ * scsi_execute - insert request and wait for the result
+ * @sdev:	scsi device
+ * @cmd:	scsi command
+ * @data_direction: data direction
+ * @buffer:	data buffer
+ * @bufflen:	len of buffer
+ * @sense:	optional sense buffer
+ * @timeout:	request timeout in seconds
+ * @retries:	number of times to retry request
+ * @flags:	or into request flags;
+ * @resid:	optional residual length
+ *
+ * returns the req->errors value which is the scsi_cmnd result
+ * field.
+ */
+int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
+		 int data_direction, void *buffer, unsigned bufflen,
+		 unsigned char *sense, int timeout, int retries, u64 flags,
+		 int *resid)
+{
+	return __scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense,
+			timeout, retries, flags, 0, resid);
+}
 EXPORT_SYMBOL(scsi_execute);
 
 int scsi_execute_req_flags(struct scsi_device *sdev, const unsigned char *cmd,
 		     int data_direction, void *buffer, unsigned bufflen,
 		     struct scsi_sense_hdr *sshdr, int timeout, int retries,
-		     int *resid, u64 flags)
+		     int *resid, u64 flags, req_flags_t rq_flags)
 {
 	char *sense = NULL;
 	int result;
@@ -242,8 +251,8 @@ int scsi_execute_req_flags(struct scsi_device *sdev, const unsigned char *cmd,
 		if (!sense)
 			return DRIVER_ERROR << 24;
 	}
-	result = scsi_execute(sdev, cmd, data_direction, buffer, bufflen,
-			      sense, timeout, retries, flags, resid);
+	result = __scsi_execute(sdev, cmd, data_direction, buffer, bufflen,
+			      sense, timeout, retries, flags, rq_flags, resid);
 	if (sshdr)
 		scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, sshdr);
 
@@ -813,7 +822,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 		 */
 		if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d))
 			;
-		else if (!(req->cmd_flags & REQ_QUIET))
+		else if (!(req->rq_flags & RQF_QUIET))
 			scsi_print_sense(cmd);
 		result = 0;
 		/* BLOCK_PC may have set error */
@@ -943,7 +952,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 	switch (action) {
 	case ACTION_FAIL:
 		/* Give up and fail the remainder of the request */
-		if (!(req->cmd_flags & REQ_QUIET)) {
+		if (!(req->rq_flags & RQF_QUIET)) {
 			static DEFINE_RATELIMIT_STATE(_rs,
 					DEFAULT_RATELIMIT_INTERVAL,
 					DEFAULT_RATELIMIT_BURST);
@@ -972,7 +981,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 		 * A new command will be prepared and issued.
 		 */
 		if (q->mq_ops) {
-			cmd->request->cmd_flags &= ~REQ_DONTPREP;
+			cmd->request->rq_flags &= ~RQF_DONTPREP;
 			scsi_mq_uninit_cmd(cmd);
 			scsi_mq_requeue_cmd(cmd);
 		} else {
@@ -998,8 +1007,8 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb)
 	/*
 	 * If sg table allocation fails, requeue request later.
 	 */
-	if (unlikely(sg_alloc_table_chained(&sdb->table, req->nr_phys_segments,
-					sdb->table.sgl)))
+	if (unlikely(sg_alloc_table_chained(&sdb->table,
+			blk_rq_nr_phys_segments(req), sdb->table.sgl)))
 		return BLKPREP_DEFER;
 
 	/* 
@@ -1031,7 +1040,7 @@ int scsi_init_io(struct scsi_cmnd *cmd)
 	bool is_mq = (rq->mq_ctx != NULL);
 	int error;
 
-	BUG_ON(!rq->nr_phys_segments);
+	BUG_ON(!blk_rq_nr_phys_segments(rq));
 
 	error = scsi_init_sgtable(rq, &cmd->sdb);
 	if (error)
@@ -1234,7 +1243,7 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 			/*
 			 * If the devices is blocked we defer normal commands.
 			 */
-			if (!(req->cmd_flags & REQ_PREEMPT))
+			if (!(req->rq_flags & RQF_PREEMPT))
 				ret = BLKPREP_DEFER;
 			break;
 		default:
@@ -1243,7 +1252,7 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 			 * special commands.  In particular any user initiated
 			 * command is not allowed.
 			 */
-			if (!(req->cmd_flags & REQ_PREEMPT))
+			if (!(req->rq_flags & RQF_PREEMPT))
 				ret = BLKPREP_KILL;
 			break;
 		}
@@ -1279,7 +1288,7 @@ scsi_prep_return(struct request_queue *q, struct request *req, int ret)
 			blk_delay_queue(q, SCSI_QUEUE_DELAY);
 		break;
 	default:
-		req->cmd_flags |= REQ_DONTPREP;
+		req->rq_flags |= RQF_DONTPREP;
 	}
 
 	return ret;
@@ -1736,7 +1745,7 @@ static void scsi_request_fn(struct request_queue *q)
 		 * we add the dev to the starved list so it eventually gets
 		 * a run when a tag is freed.
 		 */
-		if (blk_queue_tagged(q) && !(req->cmd_flags & REQ_QUEUED)) {
+		if (blk_queue_tagged(q) && !(req->rq_flags & RQF_QUEUED)) {
 			spin_lock_irq(shost->host_lock);
 			if (list_empty(&sdev->starved_entry))
 				list_add_tail(&sdev->starved_entry,
@@ -1801,7 +1810,7 @@ static inline int prep_to_mq(int ret)
 {
 	switch (ret) {
 	case BLKPREP_OK:
-		return 0;
+		return BLK_MQ_RQ_QUEUE_OK;
 	case BLKPREP_DEFER:
 		return BLK_MQ_RQ_QUEUE_BUSY;
 	default:
@@ -1888,7 +1897,7 @@ static int scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 	int reason;
 
 	ret = prep_to_mq(scsi_prep_state_check(sdev, req));
-	if (ret)
+	if (ret != BLK_MQ_RQ_QUEUE_OK)
 		goto out;
 
 	ret = BLK_MQ_RQ_QUEUE_BUSY;
@@ -1903,11 +1912,11 @@ static int scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 		goto out_dec_target_busy;
 
 
-	if (!(req->cmd_flags & REQ_DONTPREP)) {
+	if (!(req->rq_flags & RQF_DONTPREP)) {
 		ret = prep_to_mq(scsi_mq_prep_fn(req));
-		if (ret)
+		if (ret != BLK_MQ_RQ_QUEUE_OK)
 			goto out_dec_host_busy;
-		req->cmd_flags |= REQ_DONTPREP;
+		req->rq_flags |= RQF_DONTPREP;
 	} else {
 		blk_mq_start_request(req);
 	}
@@ -1941,7 +1950,6 @@ out_put_device:
 out:
 	switch (ret) {
 	case BLK_MQ_RQ_QUEUE_BUSY:
-		blk_mq_stop_hw_queue(hctx);
 		if (atomic_read(&sdev->device_busy) == 0 &&
 		    !scsi_device_blocked(sdev))
 			blk_mq_delay_queue(hctx, SCSI_QUEUE_DELAY);
@@ -1952,7 +1960,7 @@ out:
 		 * we hit an error, as we will never see this command
 		 * again.
 		 */
-		if (req->cmd_flags & REQ_DONTPREP)
+		if (req->rq_flags & RQF_DONTPREP)
 			scsi_mq_uninit_cmd(cmd);
 		break;
 	default:
@@ -1990,6 +1998,15 @@ static void scsi_exit_request(void *data, struct request *rq,
 	kfree(cmd->sense_buffer);
 }
 
+static int scsi_map_queues(struct blk_mq_tag_set *set)
+{
+	struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
+
+	if (shost->hostt->map_queues)
+		return shost->hostt->map_queues(shost);
+	return blk_mq_map_queues(set);
+}
+
 static u64 scsi_calculate_bounce_limit(struct Scsi_Host *shost)
 {
 	struct device *host_dev;
@@ -2082,6 +2099,7 @@ static struct blk_mq_ops scsi_mq_ops = {
 	.timeout	= scsi_timeout,
 	.init_request	= scsi_init_request,
 	.exit_request	= scsi_exit_request,
+	.map_queues	= scsi_map_queues,
 };
 
 struct request_queue *scsi_mq_alloc_queue(struct scsi_device *sdev)
@@ -2724,6 +2742,39 @@ void sdev_evt_send_simple(struct scsi_device *sdev,
 EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
 
 /**
+ * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn()
+ * @sdev: SCSI device to count the number of scsi_request_fn() callers for.
+ */
+static int scsi_request_fn_active(struct scsi_device *sdev)
+{
+	struct request_queue *q = sdev->request_queue;
+	int request_fn_active;
+
+	WARN_ON_ONCE(sdev->host->use_blk_mq);
+
+	spin_lock_irq(q->queue_lock);
+	request_fn_active = q->request_fn_active;
+	spin_unlock_irq(q->queue_lock);
+
+	return request_fn_active;
+}
+
+/**
+ * scsi_wait_for_queuecommand() - wait for ongoing queuecommand() calls
+ * @sdev: SCSI device pointer.
+ *
+ * Wait until the ongoing shost->hostt->queuecommand() calls that are
+ * invoked from scsi_request_fn() have finished.
+ */
+static void scsi_wait_for_queuecommand(struct scsi_device *sdev)
+{
+	WARN_ON_ONCE(sdev->host->use_blk_mq);
+
+	while (scsi_request_fn_active(sdev))
+		msleep(20);
+}
+
+/**
  *	scsi_device_quiesce - Block user issued commands.
  *	@sdev:	scsi device to quiesce.
  *
@@ -2807,8 +2858,7 @@ EXPORT_SYMBOL(scsi_target_resume);
  * @sdev:	device to block
  *
  * Block request made by scsi lld's to temporarily stop all
- * scsi commands on the specified device.  Called from interrupt
- * or normal process context.
+ * scsi commands on the specified device. May sleep.
  *
  * Returns zero if successful or error if not
  *
@@ -2817,6 +2867,10 @@ EXPORT_SYMBOL(scsi_target_resume);
  *	(which must be a legal transition).  When the device is in this
  *	state, all commands are deferred until the scsi lld reenables
  *	the device with scsi_device_unblock or device_block_tmo fires.
+ *
+ * To do: avoid that scsi_send_eh_cmnd() calls queuecommand() after
+ * scsi_internal_device_block() has blocked a SCSI device and also
+ * remove the rport mutex lock and unlock calls from srp_queuecommand().
  */
 int
 scsi_internal_device_block(struct scsi_device *sdev)
@@ -2844,6 +2898,7 @@ scsi_internal_device_block(struct scsi_device *sdev)
 		spin_lock_irqsave(q->queue_lock, flags);
 		blk_stop_queue(q);
 		spin_unlock_irqrestore(q->queue_lock, flags);
+		scsi_wait_for_queuecommand(sdev);
 	}
 
 	return 0;