1 files changed, 35 insertions, 73 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 97ff31ed2a44..ab676ce2d051 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -293,21 +293,6 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 }
 EXPORT_SYMBOL(__scsi_execute);
 
-/**
- * scsi_init_cmd_errh - Initialize cmd fields related to error handling.
- * @cmd:  command that is ready to be queued.
- *
- * This function has the job of initializing a number of fields related to error
- * handling. Typically this will be called once for each command, as required.
- */
-static void scsi_init_cmd_errh(struct scsi_cmnd *cmd)
-{
-	scsi_set_resid(cmd, 0);
-	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
-	if (cmd->cmd_len == 0)
-		cmd->cmd_len = scsi_command_size(cmd->cmnd);
-}
-
 /*
  * Wake up the error handler if necessary. Avoid as follows that the error
  * handler is not woken up if host in-flight requests number ==
@@ -530,7 +515,7 @@ static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
 	}
 }
 
-static void scsi_free_sgtables(struct scsi_cmnd *cmd)
+void scsi_free_sgtables(struct scsi_cmnd *cmd)
 {
 	if (cmd->sdb.table.nents)
 		sg_free_table_chained(&cmd->sdb.table,
@@ -539,6 +524,7 @@ static void scsi_free_sgtables(struct scsi_cmnd *cmd)
 		sg_free_table_chained(&cmd->prot_sdb->table,
 				SCSI_INLINE_PROT_SG_CNT);
 }
+EXPORT_SYMBOL_GPL(scsi_free_sgtables);
 
 static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
 {
@@ -998,7 +984,7 @@ static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
 }
 
 /**
- * scsi_init_io - SCSI I/O initialization function.
+ * scsi_alloc_sgtables - allocate S/G tables for a command
  * @cmd:  command descriptor we wish to initialize
  *
  * Returns:
@@ -1006,7 +992,7 @@ static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
  * * BLK_STS_RESOURCE - if the failure is retryable
  * * BLK_STS_IOERR    - if the failure is fatal
  */
-blk_status_t scsi_init_io(struct scsi_cmnd *cmd)
+blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd)
 {
 	struct scsi_device *sdev = cmd->device;
 	struct request *rq = cmd->request;
@@ -1098,7 +1084,7 @@ out_free_sgtables:
 	scsi_free_sgtables(cmd);
 	return ret;
 }
-EXPORT_SYMBOL(scsi_init_io);
+EXPORT_SYMBOL(scsi_alloc_sgtables);
 
 /**
  * scsi_initialize_rq - initialize struct scsi_cmnd partially
@@ -1186,7 +1172,7 @@ static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
 	 * submit a request without an attached bio.
 	 */
 	if (req->bio) {
-		blk_status_t ret = scsi_init_io(cmd);
+		blk_status_t ret = scsi_alloc_sgtables(cmd);
 		if (unlikely(ret != BLK_STS_OK))
 			return ret;
 	} else {
@@ -1196,58 +1182,16 @@ static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
 	}
 
 	cmd->cmd_len = scsi_req(req)->cmd_len;
+	if (cmd->cmd_len == 0)
+		cmd->cmd_len = scsi_command_size(cmd->cmnd);
 	cmd->cmnd = scsi_req(req)->cmd;
 	cmd->transfersize = blk_rq_bytes(req);
 	cmd->allowed = scsi_req(req)->retries;
 	return BLK_STS_OK;
 }
 
-/*
- * Setup a normal block command.  These are simple request from filesystems
- * that still need to be translated to SCSI CDBs from the ULD.
- */
-static blk_status_t scsi_setup_fs_cmnd(struct scsi_device *sdev,
-		struct request *req)
-{
-	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
-
-	if (unlikely(sdev->handler && sdev->handler->prep_fn)) {
-		blk_status_t ret = sdev->handler->prep_fn(sdev, req);
-		if (ret != BLK_STS_OK)
-			return ret;
-	}
-
-	cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd;
-	memset(cmd->cmnd, 0, BLK_MAX_CDB);
-	return scsi_cmd_to_driver(cmd)->init_command(cmd);
-}
-
-static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev,
-		struct request *req)
-{
-	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
-	blk_status_t ret;
-
-	if (!blk_rq_bytes(req))
-		cmd->sc_data_direction = DMA_NONE;
-	else if (rq_data_dir(req) == WRITE)
-		cmd->sc_data_direction = DMA_TO_DEVICE;
-	else
-		cmd->sc_data_direction = DMA_FROM_DEVICE;
-
-	if (blk_rq_is_scsi(req))
-		ret = scsi_setup_scsi_cmnd(sdev, req);
-	else
-		ret = scsi_setup_fs_cmnd(sdev, req);
-
-	if (ret != BLK_STS_OK)
-		scsi_free_sgtables(cmd);
-
-	return ret;
-}
-
 static blk_status_t
-scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
+scsi_device_state_check(struct scsi_device *sdev, struct request *req)
 {
 	switch (sdev->sdev_state) {
 	case SDEV_OFFLINE:
@@ -1589,7 +1533,7 @@ static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
 		sizeof(struct scatterlist);
 }
 
-static blk_status_t scsi_mq_prep_fn(struct request *req)
+static blk_status_t scsi_prepare_cmd(struct request *req)
 {
 	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
 	struct scsi_device *sdev = req->q->queuedata;
@@ -1601,6 +1545,10 @@ static blk_status_t scsi_mq_prep_fn(struct request *req)
 	cmd->request = req;
 	cmd->tag = req->tag;
 	cmd->prot_op = SCSI_PROT_NORMAL;
+	if (blk_rq_bytes(req))
+		cmd->sc_data_direction = rq_dma_dir(req);
+	else
+		cmd->sc_data_direction = DMA_NONE;
 
 	sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
 	cmd->sdb.table.sgl = sg;
@@ -1612,9 +1560,23 @@ static blk_status_t scsi_mq_prep_fn(struct request *req)
 			(struct scatterlist *)(cmd->prot_sdb + 1);
 	}
 
-	blk_mq_start_request(req);
+	/*
+	 * Special handling for passthrough commands, which don't go to the ULP
+	 * at all:
+	 */
+	if (blk_rq_is_scsi(req))
+		return scsi_setup_scsi_cmnd(sdev, req);
+
+	if (sdev->handler && sdev->handler->prep_fn) {
+		blk_status_t ret = sdev->handler->prep_fn(sdev, req);
 
-	return scsi_setup_cmnd(sdev, req);
+		if (ret != BLK_STS_OK)
+			return ret;
+	}
+
+	cmd->cmnd = scsi_req(req)->cmd = scsi_req(req)->__cmd;
+	memset(cmd->cmnd, 0, BLK_MAX_CDB);
+	return scsi_cmd_to_driver(cmd)->init_command(cmd);
 }
 
 static void scsi_mq_done(struct scsi_cmnd *cmd)
@@ -1680,7 +1642,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 	 * commands.
 	 */
 	if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
-		ret = scsi_prep_state_check(sdev, req);
+		ret = scsi_device_state_check(sdev, req);
 		if (ret != BLK_STS_OK)
 			goto out_put_budget;
 	}
@@ -1692,13 +1654,12 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 		goto out_dec_target_busy;
 
 	if (!(req->rq_flags & RQF_DONTPREP)) {
-		ret = scsi_mq_prep_fn(req);
+		ret = scsi_prepare_cmd(req);
 		if (ret != BLK_STS_OK)
 			goto out_dec_host_busy;
 		req->rq_flags |= RQF_DONTPREP;
 	} else {
 		clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
-		blk_mq_start_request(req);
 	}
 
 	cmd->flags &= SCMD_PRESERVED_FLAGS;
@@ -1707,9 +1668,11 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (bd->last)
 		cmd->flags |= SCMD_LAST;
 
-	scsi_init_cmd_errh(cmd);
+	scsi_set_resid(cmd, 0);
+	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
 	cmd->scsi_done = scsi_mq_done;
 
+	blk_mq_start_request(req);
 	reason = scsi_dispatch_cmd(cmd);
 	if (reason) {
 		scsi_set_blocked(cmd, reason);
@@ -1970,7 +1933,6 @@ struct scsi_device *scsi_device_from_queue(struct request_queue *q)
 
 	return sdev;
 }
-EXPORT_SYMBOL_GPL(scsi_device_from_queue);
 
 /**
  * scsi_block_requests - Utility function used by low-level drivers to prevent