block: allow blk_rq_map_kern to append to requests
Use blk_rq_append_bio() internally instead of blk_rq_bio_prep()
so blk_rq_map_kern can be called multiple times, to map multiple
buffers.
This is in the effort to un-export blk_rq_append_bio()
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/blk-map.c b/block/blk-map.c
index 56082be..caa05a6 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -282,7 +282,8 @@
*
* Description:
* Data will be mapped directly if possible. Otherwise a bounce
- * buffer is used.
+ * buffer is used. Can be called multple times to append multple
+ * buffers.
*/
int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
unsigned int len, gfp_t gfp_mask)
@@ -290,6 +291,7 @@
int reading = rq_data_dir(rq) == READ;
int do_copy = 0;
struct bio *bio;
+ int ret;
if (len > (q->max_hw_sectors << 9))
return -EINVAL;
@@ -311,7 +313,13 @@
if (do_copy)
rq->cmd_flags |= REQ_COPY_USER;
- blk_rq_bio_prep(q, rq, bio);
+ ret = blk_rq_append_bio(q, rq, bio);
+ if (unlikely(ret)) {
+ /* request is too big */
+ bio_put(bio);
+ return ret;
+ }
+
blk_queue_bounce(q, &rq->bio);
rq->buffer = NULL;
return 0;