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>
This commit is contained in:
Christoph Hellwig 2016-07-19 11:31:50 +02:00 committed by Jens Axboe
parent f9596695be
commit 0c4de0f33b
4 changed files with 11 additions and 10 deletions

View File

@ -1294,10 +1294,15 @@ static struct request *blk_old_get_request(struct request_queue *q, int rw,
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 @@ EXPORT_SYMBOL(blk_make_request);
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);

View File

@ -263,6 +263,10 @@ struct request *blk_mq_alloc_request(struct request_queue *q, int rw,
blk_queue_exit(q);
return ERR_PTR(-EWOULDBLOCK);
}
rq->__data_len = 0;
rq->__sector = (sector_t) -1;
rq->bio = rq->biotail = NULL;
return rq;
}
EXPORT_SYMBOL(blk_mq_alloc_request);

View File

@ -243,7 +243,6 @@ static int virtblk_get_id(struct gendisk *disk, char *id_str)
req = blk_get_request(q, READ, GFP_KERNEL);
if (IS_ERR(req))
return PTR_ERR(req);
blk_rq_set_block_pc(req);
req->cmd_type = REQ_TYPE_DRV_PRIV;
err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL);

View File

@ -222,10 +222,6 @@ struct request *nvme_alloc_request(struct request_queue *q,
req->cmd_type = REQ_TYPE_DRV_PRIV;
req->cmd_flags |= REQ_FAILFAST_DRIVER;
req->__data_len = 0;
req->__sector = (sector_t) -1;
req->bio = req->biotail = NULL;
req->cmd = (unsigned char *)cmd;
req->cmd_len = sizeof(struct nvme_command);