scsi: clean up error handling in scsi_init_io

There is no need to call scsi_mq_free_sgtables until we have actually
allocated sgtables.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index e665c25..1f84e2c 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1044,31 +1044,30 @@ int scsi_init_io(struct scsi_cmnd *cmd)
        int error = BLKPREP_KILL;
 
        if (WARN_ON_ONCE(!blk_rq_nr_phys_segments(rq)))
-               goto err_exit;
+               return BLKPREP_KILL;
 
        error = scsi_init_sgtable(rq, &cmd->sdb);
        if (error)
-               goto err_exit;
+               return error;
 
        if (blk_bidi_rq(rq)) {
                error = scsi_init_sgtable(rq->next_rq, rq->next_rq->special);
                if (error)
-                       goto err_exit;
+                       goto out_free_sgtables;
        }
 
        if (blk_integrity_rq(rq)) {
                struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
                int ivecs, count;
 
-               if (prot_sdb == NULL) {
+               if (WARN_ON_ONCE(!prot_sdb)) {
                        /*
                         * This can happen if someone (e.g. multipath)
                         * queues a command to a device on an adapter
                         * that does not support DIX.
                         */
-                       WARN_ON_ONCE(1);
                        error = BLKPREP_KILL;
-                       goto err_exit;
+                       goto out_free_sgtables;
                }
 
                ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
@@ -1076,7 +1075,7 @@ int scsi_init_io(struct scsi_cmnd *cmd)
                if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
                                prot_sdb->table.sgl)) {
                        error = BLKPREP_DEFER;
-                       goto err_exit;
+                       goto out_free_sgtables;
                }
 
                count = blk_rq_map_integrity_sg(rq->q, rq->bio,
@@ -1089,7 +1088,7 @@ int scsi_init_io(struct scsi_cmnd *cmd)
        }
 
        return BLKPREP_OK;
-err_exit:
+out_free_sgtables:
        scsi_mq_free_sgtables(cmd);
        return error;
 }