diff options
author | Jens Axboe <axboe@kernel.dk> | 2017-12-18 15:40:44 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2017-12-18 13:55:43 -0700 |
commit | 0abc2a10389f0c9070f76ca906c7382788036b93 (patch) | |
tree | 9d1f1b48a3acbff7ed8b1549ebb1cffe3b407b81 /block | |
parent | 14cb0dc6479dc5ebc63b3a459a5d89a2f1b39fed (diff) | |
download | linux-0abc2a10389f0c9070f76ca906c7382788036b93.tar.bz2 |
block: fix blk_rq_append_bio
Commit caa4b02476e3(blk-map: call blk_queue_bounce from blk_rq_append_bio)
moves blk_queue_bounce() into blk_rq_append_bio(), but don't consider
the fact that the bounced bio becomes invisible to caller since the
parameter type is 'struct bio *'. Make it a pointer to a pointer to
a bio, so the caller sees the right bio also after a bounce.
Fixes: caa4b02476e3 ("blk-map: call blk_queue_bounce from blk_rq_append_bio")
Cc: Christoph Hellwig <hch@lst.de>
Reported-by: Michele Ballabio <barra_cuda@katamail.com>
(handling failure of blk_rq_append_bio(), only call bio_get() after
blk_rq_append_bio() returns OK)
Tested-by: Michele Ballabio <barra_cuda@katamail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r-- | block/blk-map.c | 38 |
1 files changed, 22 insertions, 16 deletions
diff --git a/block/blk-map.c b/block/blk-map.c index b21f8e86f120..d3a94719f03f 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -12,22 +12,29 @@ #include "blk.h" /* - * Append a bio to a passthrough request. Only works can be merged into - * the request based on the driver constraints. + * Append a bio to a passthrough request. Only works if the bio can be merged + * into the request based on the driver constraints. */ -int blk_rq_append_bio(struct request *rq, struct bio *bio) +int blk_rq_append_bio(struct request *rq, struct bio **bio) { - blk_queue_bounce(rq->q, &bio); + struct bio *orig_bio = *bio; + + blk_queue_bounce(rq->q, bio); if (!rq->bio) { - blk_rq_bio_prep(rq->q, rq, bio); + blk_rq_bio_prep(rq->q, rq, *bio); } else { - if (!ll_back_merge_fn(rq->q, rq, bio)) + if (!ll_back_merge_fn(rq->q, rq, *bio)) { + if (orig_bio != *bio) { + bio_put(*bio); + *bio = orig_bio; + } return -EINVAL; + } - rq->biotail->bi_next = bio; - rq->biotail = bio; - rq->__data_len += bio->bi_iter.bi_size; + rq->biotail->bi_next = *bio; + rq->biotail = *bio; + rq->__data_len += (*bio)->bi_iter.bi_size; } return 0; @@ -73,14 +80,12 @@ static int __blk_rq_map_user_iov(struct request *rq, * We link the bounce buffer in and could have to traverse it * later so we have to get a ref to prevent it from being freed */ - ret = blk_rq_append_bio(rq, bio); - bio_get(bio); + ret = blk_rq_append_bio(rq, &bio); if (ret) { - bio_endio(bio); __blk_rq_unmap_user(orig_bio); - bio_put(bio); return ret; } + bio_get(bio); return 0; } @@ -213,7 +218,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, int reading = rq_data_dir(rq) == READ; unsigned long addr = (unsigned long) kbuf; int do_copy = 0; - struct bio *bio; + struct bio *bio, *orig_bio; int ret; if (len > (queue_max_hw_sectors(q) << 9)) @@ -236,10 +241,11 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, if (do_copy) rq->rq_flags |= RQF_COPY_USER; - ret = blk_rq_append_bio(rq, bio); + orig_bio = bio; + ret = blk_rq_append_bio(rq, &bio); if (unlikely(ret)) { /* request is too big */ - bio_put(bio); + bio_put(orig_bio); return ret; } |