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| author | Ming Lei <ming.lei@redhat.com> | 2017-12-18 10:40:43 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2017-12-18 23:55:43 +0300 |
| commit | 14cb0dc6479dc5ebc63b3a459a5d89a2f1b39fed (patch) | |
| tree | db336ec3ba6267370615b5bc60c104f03f924bef /block | |
| parent | a9fa99146ab4fc029ba5551a1a3a0102fae7fddf (diff) | |
| download | linux-14cb0dc6479dc5ebc63b3a459a5d89a2f1b39fed.tar.xz | |
block: don't let passthrough IO go into .make_request_fn()
Commit a8821f3f3("block: Improvements to bounce-buffer handling") tries
to make sure that the bio to .make_request_fn won't exceed BIO_MAX_PAGES,
but ignores that passthrough I/O can use blk_queue_bounce() too.
Especially, passthrough IO may not be sector-aligned, and the check
of 'sectors < bio_sectors(*bio_orig)' inside __blk_queue_bounce() may
become true even though the max bvec number doesn't exceed BIO_MAX_PAGES,
then cause the bio splitted, and the original passthrough bio is submited
to generic_make_request().
This patch fixes this issue by checking if the bio is passthrough IO,
and use bio_kmalloc() to allocate the cloned passthrough bio.
Cc: NeilBrown <neilb@suse.com>
Fixes: a8821f3f3("block: Improvements to bounce-buffer handling")
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/bounce.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/block/bounce.c b/block/bounce.c index fceb1a96480b..1d05c422c932 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -200,6 +200,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, unsigned i = 0; bool bounce = false; int sectors = 0; + bool passthrough = bio_is_passthrough(*bio_orig); bio_for_each_segment(from, *bio_orig, iter) { if (i++ < BIO_MAX_PAGES) @@ -210,13 +211,14 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, if (!bounce) return; - if (sectors < bio_sectors(*bio_orig)) { + if (!passthrough && sectors < bio_sectors(*bio_orig)) { bio = bio_split(*bio_orig, sectors, GFP_NOIO, bounce_bio_split); bio_chain(bio, *bio_orig); generic_make_request(*bio_orig); *bio_orig = bio; } - bio = bio_clone_bioset(*bio_orig, GFP_NOIO, bounce_bio_set); + bio = bio_clone_bioset(*bio_orig, GFP_NOIO, passthrough ? NULL : + bounce_bio_set); bio_for_each_segment_all(to, bio, i) { struct page *page = to->bv_page; |