From 14eacf12dbc75352fa746dfd9e24de3170ba5ff5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 11 Apr 2019 08:23:29 +0200 Subject: [PATCH] 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 Reviewed-by: Bart Van Assche Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/bio.c | 15 ++++++--------- 1 file 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) -- 2.30.2