__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: Christoph Hellwig <hch@xxxxxx>
---
block/bio.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index d020065e613cc8..c7bf20a779ebed 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -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;
@@ -1328,6 +1328,9 @@ 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);
--
2.39.2
