diff options
| author | Christoph Hellwig <hch@lst.de> | 2019-04-11 08:23:29 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-04-12 09:06:39 -0600 |
| commit | 14eacf12dbc75352fa746dfd9e24de3170ba5ff5 (patch) | |
| tree | 9a567a65a6a3582ec92a93955f6e7a713448e038 /block/bio.c | |
| parent | a10584c3cda9cbb1a1ccd072783bfd625f99e40d (diff) | |
| download | lwn-14eacf12dbc75352fa746dfd9e24de3170ba5ff5.tar.gz lwn-14eacf12dbc75352fa746dfd9e24de3170ba5ff5.zip | |
block: don't allow multiple bio_iov_iter_get_pages calls per bio
No caller uses bio_iov_iter_get_pages multiple times on a given bio,
and that funtionality isn't all that useful. Removing it will make
some future changes a little easier and also simplifies the function
a bit.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/bio.c')
| -rw-r--r-- | block/bio.c | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/block/bio.c b/block/bio.c index ad346082a971..c2a389b1509a 100644 --- a/block/bio.c +++ b/block/bio.c @@ -958,7 +958,10 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) { const bool is_bvec = iov_iter_is_bvec(iter); - unsigned short orig_vcnt = bio->bi_vcnt; + int ret; + + if (WARN_ON_ONCE(bio->bi_vcnt)) + return -EINVAL; /* * If this is a BVEC iter, then the pages are kernel pages. Don't @@ -968,19 +971,13 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) bio_set_flag(bio, BIO_NO_PAGE_REF); do { - int ret; - if (is_bvec) ret = __bio_iov_bvec_add_pages(bio, iter); else ret = __bio_iov_iter_get_pages(bio, iter); + } while (!ret && iov_iter_count(iter) && !bio_full(bio)); - if (unlikely(ret)) - return bio->bi_vcnt > orig_vcnt ? 0 : ret; - - } while (iov_iter_count(iter) && !bio_full(bio)); - - return 0; + return bio->bi_vcnt ? 0 : ret; } static void submit_bio_wait_endio(struct bio *bio) |