diff options
| -rw-r--r-- | block/bio.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/block/bio.c b/block/bio.c index 5959141d4e46..c81ed2dfee53 100644 --- a/block/bio.c +++ b/block/bio.c @@ -667,6 +667,8 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return false; } + WARN_ON_ONCE(same_page && (len + off) > PAGE_SIZE); + return true; } @@ -786,9 +788,9 @@ EXPORT_SYMBOL(bio_add_pc_page); /** * __bio_try_merge_page - try appending data to an existing bvec. * @bio: destination bio - * @page: page to add + * @page: start page to add * @len: length of the data to add - * @off: offset of the data in @page + * @off: offset of the data relative to @page * @same_page: if %true only merge if the new data is in the same physical * page as the last segment of the bio. * @@ -796,6 +798,8 @@ EXPORT_SYMBOL(bio_add_pc_page); * a useful optimisation for file systems with a block size smaller than the * page size. * + * Warn if (@len, @off) crosses pages in case that @same_page is true. + * * Return %true on success or %false on failure. */ bool __bio_try_merge_page(struct bio *bio, struct page *page, @@ -818,11 +822,11 @@ bool __bio_try_merge_page(struct bio *bio, struct page *page, EXPORT_SYMBOL_GPL(__bio_try_merge_page); /** - * __bio_add_page - add page to a bio in a new segment + * __bio_add_page - add page(s) to a bio in a new segment * @bio: destination bio - * @page: page to add - * @len: length of the data to add - * @off: offset of the data in @page + * @page: start page to add + * @len: length of the data to add, may cross pages + * @off: offset of the data relative to @page, may cross pages * * Add the data at @page + @off to @bio as a new bvec. The caller must ensure * that @bio has space for another bvec. @@ -845,13 +849,13 @@ void __bio_add_page(struct bio *bio, struct page *page, EXPORT_SYMBOL_GPL(__bio_add_page); /** - * bio_add_page - attempt to add page to bio + * bio_add_page - attempt to add page(s) to bio * @bio: destination bio - * @page: page to add - * @len: vec entry length - * @offset: vec entry offset + * @page: start page to add + * @len: vec entry length, may cross pages + * @offset: vec entry offset relative to @page, may cross pages * - * Attempt to add a page to the bio_vec maplist. This will only fail + * Attempt to add page(s) to the bio_vec maplist. This will only fail * if either bio->bi_vcnt == bio->bi_max_vecs or it's a cloned bio. */ int bio_add_page(struct bio *bio, struct page *page, |