1 files changed, 59 insertions, 39 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 610ee41fa54c..47835c4b4ee0 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -562,7 +562,6 @@ static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
 {
 	scsi_mq_free_sgtables(cmd);
 	scsi_uninit_cmd(cmd);
-	scsi_del_cmd_from_list(cmd);
 }
 
 /* Returns false when no more bytes to process, true if there are more */
@@ -1098,36 +1097,7 @@ static void scsi_cleanup_rq(struct request *rq)
 	}
 }
 
-/* Add a command to the list used by the aacraid and dpt_i2o drivers */
-void scsi_add_cmd_to_list(struct scsi_cmnd *cmd)
-{
-	struct scsi_device *sdev = cmd->device;
-	struct Scsi_Host *shost = sdev->host;
-	unsigned long flags;
-
-	if (shost->use_cmd_list) {
-		spin_lock_irqsave(&sdev->list_lock, flags);
-		list_add_tail(&cmd->list, &sdev->cmd_list);
-		spin_unlock_irqrestore(&sdev->list_lock, flags);
-	}
-}
-
-/* Remove a command from the list used by the aacraid and dpt_i2o drivers */
-void scsi_del_cmd_from_list(struct scsi_cmnd *cmd)
-{
-	struct scsi_device *sdev = cmd->device;
-	struct Scsi_Host *shost = sdev->host;
-	unsigned long flags;
-
-	if (shost->use_cmd_list) {
-		spin_lock_irqsave(&sdev->list_lock, flags);
-		BUG_ON(list_empty(&cmd->list));
-		list_del_init(&cmd->list);
-		spin_unlock_irqrestore(&sdev->list_lock, flags);
-	}
-}
-
-/* Called after a request has been started. */
+/* Called before a request is prepared. See also scsi_mq_prep_fn(). */
 void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
 {
 	void *buf = cmd->sense_buffer;
@@ -1135,7 +1105,7 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
 	struct request *rq = blk_mq_rq_from_pdu(cmd);
 	unsigned int flags = cmd->flags & SCMD_PRESERVED_FLAGS;
 	unsigned long jiffies_at_alloc;
-	int retries;
+	int retries, to_clear;
 	bool in_flight;
 
 	if (!blk_rq_is_scsi(rq) && !(flags & SCMD_INITIALIZED)) {
@@ -1146,9 +1116,15 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
 	jiffies_at_alloc = cmd->jiffies_at_alloc;
 	retries = cmd->retries;
 	in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
-	/* zero out the cmd, except for the embedded scsi_request */
-	memset((char *)cmd + sizeof(cmd->req), 0,
-		sizeof(*cmd) - sizeof(cmd->req) + dev->host->hostt->cmd_size);
+	/*
+	 * Zero out the cmd, except for the embedded scsi_request. Only clear
+	 * the driver-private command data if the LLD does not supply a
+	 * function to initialize that data.
+	 */
+	to_clear = sizeof(*cmd) - sizeof(cmd->req);
+	if (!dev->host->hostt->init_cmd_priv)
+		to_clear += dev->host->hostt->cmd_size;
+	memset((char *)cmd + sizeof(cmd->req), 0, to_clear);
 
 	cmd->device = dev;
 	cmd->sense_buffer = buf;
@@ -1160,7 +1136,6 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
 	if (in_flight)
 		__set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
 
-	scsi_add_cmd_to_list(cmd);
 }
 
 static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
@@ -1240,8 +1215,11 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 		 * commands.  The device must be brought online
 		 * before trying any recovery commands.
 		 */
-		sdev_printk(KERN_ERR, sdev,
-			    "rejecting I/O to offline device\n");
+		if (!sdev->offline_already) {
+			sdev->offline_already = true;
+			sdev_printk(KERN_ERR, sdev,
+				    "rejecting I/O to offline device\n");
+		}
 		return BLK_STS_IOERR;
 	case SDEV_DEL:
 		/*
@@ -1742,6 +1720,7 @@ static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
 	const bool unchecked_isa_dma = shost->unchecked_isa_dma;
 	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
 	struct scatterlist *sg;
+	int ret = 0;
 
 	if (unchecked_isa_dma)
 		cmd->flags |= SCMD_UNCHECKED_ISA_DMA;
@@ -1757,14 +1736,24 @@ static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
 		cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
 	}
 
-	return 0;
+	if (shost->hostt->init_cmd_priv) {
+		ret = shost->hostt->init_cmd_priv(shost, cmd);
+		if (ret < 0)
+			scsi_free_sense_buffer(unchecked_isa_dma,
+					       cmd->sense_buffer);
+	}
+
+	return ret;
 }
 
 static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
 				 unsigned int hctx_idx)
 {
+	struct Scsi_Host *shost = set->driver_data;
 	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
 
+	if (shost->hostt->exit_cmd_priv)
+		shost->hostt->exit_cmd_priv(shost, cmd);
 	scsi_free_sense_buffer(cmd->flags & SCMD_UNCHECKED_ISA_DMA,
 			       cmd->sense_buffer);
 }
@@ -2340,6 +2329,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 		break;
 
 	}
+	sdev->offline_already = false;
 	sdev->sdev_state = state;
 	return 0;
 
@@ -2845,6 +2835,36 @@ scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
 }
 EXPORT_SYMBOL_GPL(scsi_target_unblock);
 
+int
+scsi_host_block(struct Scsi_Host *shost)
+{
+	struct scsi_device *sdev;
+	int ret = 0;
+
+	shost_for_each_device(sdev, shost) {
+		ret = scsi_internal_device_block(sdev);
+		if (ret)
+			break;
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(scsi_host_block);
+
+int
+scsi_host_unblock(struct Scsi_Host *shost, int new_state)
+{
+	struct scsi_device *sdev;
+	int ret = 0;
+
+	shost_for_each_device(sdev, shost) {
+		ret = scsi_internal_device_unblock(sdev, new_state);
+		if (ret)
+			break;
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(scsi_host_unblock);
+
 /**
  * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt
  * @sgl:	scatter-gather list