07_scsi_consolidate_prep_fn_error_handling.patch
When scsi_init_io() returns BLKPREP_DEFER or BLKPREP_KILL,
it's supposed to free resources itself. This patch
consolidates defer and kill handling into scsi_prep_fn().
This fixes a queue stall bug which occurred when sgtable
allocation failed and device_busy == 0.
Signed-off-by: Tejun Heo <[EMAIL PROTECTED]>
scsi_lib.c | 23 ++++++++++++-----------
1 files changed, 12 insertions(+), 11 deletions(-)
Index: scsi-export/drivers/scsi/scsi_lib.c
===================================================================
--- scsi-export.orig/drivers/scsi/scsi_lib.c 2005-03-31 18:06:21.000000000
+0900
+++ scsi-export/drivers/scsi/scsi_lib.c 2005-03-31 18:06:21.000000000 +0900
@@ -960,9 +960,6 @@ static int scsi_init_io(struct scsi_cmnd
printk(KERN_ERR "req nr_sec %lu, cur_nr_sec %u\n", req->nr_sectors,
req->current_nr_sectors);
- /* release the command and kill it */
- scsi_release_buffers(cmd);
- scsi_put_command(cmd);
return BLKPREP_KILL;
}
@@ -1130,18 +1127,17 @@ static int scsi_prep_fn(struct request_q
* required).
*/
ret = scsi_init_io(cmd);
- if (ret) /* BLKPREP_KILL return also releases the
command */
- return ret;
-
+ if (ret == BLKPREP_DEFER)
+ goto defer;
+ else if (ret == BLKPREP_KILL)
+ goto kill;
+
/*
* Initialize the actual SCSI command for this request.
*/
drv = *(struct scsi_driver **)req->rq_disk->private_data;
- if (unlikely(!drv->init_command(cmd))) {
- scsi_release_buffers(cmd);
- scsi_put_command(cmd);
- return BLKPREP_KILL;
- }
+ if (unlikely(!drv->init_command(cmd)))
+ goto kill;
}
/*
@@ -1157,6 +1153,11 @@ static int scsi_prep_fn(struct request_q
if (sdev->device_busy == 0)
blk_plug_device(q);
return BLKPREP_DEFER;
+
+ kill:
+ scsi_release_buffers(cmd);
+ scsi_put_command(cmd);
+ return BLKPREP_KILL;
}
/*
-
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