scsi: move the nr_phys_segments assert into scsi_init_io

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>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 60031e15d562b4aa86c92a6003b488d9f49c60ee..26e1afec564057f49baebd67af597522f2efd2bc 100644 (file)
--- 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;