block: ensure bios return from blk_get_request are properly initialized
blk_get_request is used for BLOCK_PC and similar passthrough requests.
Currently we always need to call blk_rq_set_block_pc or an open coded
version of it to allow appending bios using the request mapping helpers
later on, which is a somewhat awkward API. Instead move the
initialization part of blk_rq_set_block_pc into blk_get_request, so that
we always have a safe to use request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index dd32563..4d87949 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1294,10 +1294,15 @@
spin_lock_irq(q->queue_lock);
rq = get_request(q, rw, 0, NULL, gfp_mask);
- if (IS_ERR(rq))
+ if (IS_ERR(rq)) {
spin_unlock_irq(q->queue_lock);
- /* q->queue_lock is unlocked at this point */
+ return rq;
+ }
+ /* q->queue_lock is unlocked at this point */
+ rq->__data_len = 0;
+ rq->__sector = (sector_t) -1;
+ rq->bio = rq->biotail = NULL;
return rq;
}
@@ -1377,9 +1382,6 @@
void blk_rq_set_block_pc(struct request *rq)
{
rq->cmd_type = REQ_TYPE_BLOCK_PC;
- rq->__data_len = 0;
- rq->__sector = (sector_t) -1;
- rq->bio = rq->biotail = NULL;
memset(rq->__cmd, 0, sizeof(rq->__cmd));
}
EXPORT_SYMBOL(blk_rq_set_block_pc);