Commit 939e1a37 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: move the BIO_CLONED checks out of __bio_try_merge_page 



__bio_try_merge_page is a way too low-level helper to assert that the
bio is not cloned.  Move the check into bio_add_page and
bio_iov_iter_get_pages instead, which are the high level entry points
that should enforce this variant.  bio_add_hw_page already this
check, coverig the third (indirect) caller of __bio_try_merge_page.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJinyoung Choi <j-young.choi@samsung.com>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20230724165433.117645-4-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 6850b2dd

block/bio.c

+6 −3
Original line number Diff line number Diff line
@@ -945,9 +945,6 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, 
static bool __bio_try_merge_page(struct bio *bio, struct page *page,

		unsigned int len, unsigned int off, bool *same_page)

{

	if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))

		return false;



	if (bio->bi_vcnt > 0) {

		struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
@@ -1127,6 +1124,9 @@ int bio_add_page(struct bio *bio, struct page *page, 
{

	bool same_page = false;



	if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))

		return 0;



	if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) {

		if (bio_full(bio, len))

			return 0;
@@ -1335,6 +1335,9 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) 
{

	int ret = 0;



	if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))

		return -EIO;



	if (iov_iter_is_bvec(iter)) {

		bio_iov_bvec_set(bio, iter);

		iov_iter_advance(iter, bio->bi_iter.bi_size);