[PATCH 3/5] add retries field to request for REQ_BLOCK_PC use

[PATCH 3/5] add retries field to request for REQ_BLOCK_PC use

[Mike Christie]

For tape we need to control the retries. This patch adds a retries
counter on the request for REQ_PC commands to use.

For block SG_IO commands we set the retries to 1. This is the same
as before for sd, but for sr this decreases the retries where it
used to be 3. If the latter behavior is not correct I can send a
patch over this one so that we only use the retries counter
for REQ_PC commands initiated from scsi-ml and the scsi ULDs.


Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>


diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 382dea7..fdfa064 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -303,6 +303,7 @@ static int sg_io(struct file *file, requ
 		rq->timeout = q->sg_timeout;
 	if (!rq->timeout)
 		rq->timeout = BLK_DEFAULT_TIMEOUT;
+	rq->retries = 1;
 
 	start_time = jiffies;
 
@@ -413,6 +414,7 @@ static int sg_scsi_ioctl(struct file *fi
 			rq->timeout = BLK_DEFAULT_TIMEOUT;
 			break;
 	}
+	rq->retries = 1;
 
 	memset(sense, 0, sizeof(sense));
 	rq->sense = sense;
@@ -571,6 +573,7 @@ int scsi_cmd_ioctl(struct file *file, st
 			rq->data = NULL;
 			rq->data_len = 0;
 			rq->timeout = BLK_DEFAULT_TIMEOUT;
+			rq->retries = 1;
 			memset(rq->cmd, 0, sizeof(rq->cmd));
 			rq->cmd[0] = GPCMD_START_STOP_UNIT;
 			rq->cmd[4] = 0x02 + (close != 0);
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 1abfc38..55e3faa 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -259,6 +259,7 @@ int scsi_execute(struct scsi_device *sde
 	memcpy(req->cmd, cmd, req->cmd_len);
 	req->sense = sense;
 	req->sense_len = 0;
+	req->retries = retries;
 	req->timeout = timeout;
 	req->flags |= flags | REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;
 
@@ -472,6 +473,7 @@ int scsi_execute_async(struct scsi_devic
 	req->sense = sioc->sense;
 	req->sense_len = 0;
 	req->timeout = timeout;
+	req->retries = retries;
 	req->flags |= REQ_BLOCK_PC | REQ_QUIET;
 	req->end_io_data = sioc;
 
@@ -1392,7 +1394,7 @@ static int scsi_prep_fn(struct request_q
 				cmd->sc_data_direction = DMA_NONE;
 			
 			cmd->transfersize = req->data_len;
-			cmd->allowed = 3;
+			cmd->allowed = req->retries;
 			cmd->timeout_per_command = req->timeout;
 			cmd->done = scsi_generic_done;
 		}
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8613a13..2efad67 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -86,7 +86,6 @@
  * Number of allowed retries
  */
 #define SD_MAX_RETRIES		5
-#define SD_PASSTHROUGH_RETRIES	1
 
 static void scsi_disk_release(struct kref *kref);
 
@@ -262,7 +261,7 @@ static int sd_init_command(struct scsi_c
 			timeout = rq->timeout;
 
 		SCpnt->transfersize = rq->data_len;
-		SCpnt->allowed = SD_PASSTHROUGH_RETRIES;
+		SCpnt->allowed = rq->retries;
 		goto queue;
 	}
 
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index d68cea7..bbcf428 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -338,6 +338,7 @@ static int sr_init_command(struct scsi_c
 		if (rq->timeout)
 			timeout = rq->timeout;
 
+		SCpnt->allowed = rq->retries;
 		SCpnt->transfersize = rq->data_len;
 		goto queue;
 	}
@@ -435,9 +436,8 @@ static int sr_init_command(struct scsi_c
 	 */
 	SCpnt->transfersize = cd->device->sector_size;
 	SCpnt->underflow = this_count << 9;
-
-queue:
 	SCpnt->allowed = MAX_RETRIES;
+queue:
 	SCpnt->timeout_per_command = timeout;
 
 	/*
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 770c432..8a99246 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -4213,6 +4213,7 @@ static int st_init_command(struct scsi_c
 	else
 		SCpnt->sc_data_direction = DMA_NONE;
 
+	SCpnt->allowed = rq->retries;
 	SCpnt->timeout_per_command = rq->timeout;
 	SCpnt->transfersize = rq->data_len;
 	SCpnt->done = st_intr;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 46e927b..ced54ea 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -184,6 +184,7 @@ struct request {
 	void *sense;
 
 	unsigned int timeout;
+	int retries;
 
 	/*
 	 * For Power Management requests