[PATCH 3.10 067/268] scsi: move the nr_phys_segments assert into scsi_init_io

Willy Tarreau
2017-06-19T19:25:57Z

From: Christoph Hellwig <hch@lst.de>

commit 635d98b1d0cfc2ba3426a701725d31a6102c059a upstream.

scsi_init_io should only be called for requests that transfer data,
so move the assert that a request has segments from the callers into
scsi_init_io.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/scsi/scsi_lib.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 60031e1..26e1afe 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1009,8 +1009,11 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb,
int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask)
{
struct request *rq = cmd->request;
+ int error;

- int error = scsi_init_sgtable(rq, &cmd->sdb, gfp_mask);
+ BUG_ON(!rq->nr_phys_segments);
+
+ error = scsi_init_sgtable(rq, &cmd->sdb, gfp_mask);
if (error)
goto err_exit;

@@ -1102,11 +1105,7 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
* submit a request without an attached bio.
*/
if (req->bio) {
- int ret;
-
- BUG_ON(!req->nr_phys_segments);
-
- ret = scsi_init_io(cmd, GFP_ATOMIC);
+ int ret = scsi_init_io(cmd, GFP_ATOMIC);
if (unlikely(ret))
return ret;
} else {
@@ -1150,11 +1149,6 @@ int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
return ret;
}

- /*
- * Filesystem requests must transfer data.
- */
- BUG_ON(!req->nr_phys_segments);
-
cmd = scsi_get_cmd_from_req(sdev, req);
if (unlikely(!cmd))
return BLKPREP_DEFER;
--
2.8.0.rc2.1.gbe9624a