6.5-stable review patch. If anyone has any objections, please let me know.
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From: Christoph Hellwig hch@lst.de
[ Upstream commit 858c708d9efb7e8e5c6320793b778cc17cf8368a ]
The update of bi_size is the only thing in __bio_try_merge_page that needs a bio. Move it to the callers, and merge __bio_try_merge_page and page_is_mergeable into a single bvec_try_merge_page that only takes the current bvec instead of a full bio. This will allow reusing this function for supporting multi-page integrity payload bvecs.
Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Jinyoung Choi j-young.choi@samsung.com Link: https://lore.kernel.org/r/20230724165433.117645-8-hch@lst.de Signed-off-by: Jens Axboe axboe@kernel.dk Stable-dep-of: 0ece1d649b6d ("bio-integrity: create multi-page bvecs in bio_integrity_add_page()") Signed-off-by: Sasha Levin sashal@kernel.org --- block/bio.c | 57 +++++++++++++++++++---------------------------------- 1 file changed, 20 insertions(+), 37 deletions(-)
diff --git a/block/bio.c b/block/bio.c index b9b8328d1bc82..c30f7489e4482 100644 --- a/block/bio.c +++ b/block/bio.c @@ -903,9 +903,8 @@ static inline bool bio_full(struct bio *bio, unsigned len) return false; }
-static inline bool page_is_mergeable(const struct bio_vec *bv, - struct page *page, unsigned int len, unsigned int off, - bool *same_page) +static bool bvec_try_merge_page(struct bio_vec *bv, struct page *page, + unsigned int len, unsigned int off, bool *same_page) { size_t bv_end = bv->bv_offset + bv->bv_len; phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + bv_end - 1; @@ -919,38 +918,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return false;
*same_page = ((vec_end_addr & PAGE_MASK) == page_addr); - if (*same_page) - return true; - else if (IS_ENABLED(CONFIG_KMSAN)) - return false; - return (bv->bv_page + bv_end / PAGE_SIZE) == (page + off / PAGE_SIZE); -} - -/** - * __bio_try_merge_page - try appending data to an existing bvec. - * @bio: destination bio - * @page: start page to add - * @len: length of the data to add - * @off: offset of the data relative to @page - * @same_page: return if the segment has been merged inside the same page - * - * Try to add the data at @page + @off to the last bvec of @bio. This is 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. - */ -static bool __bio_try_merge_page(struct bio *bio, struct page *page, - unsigned int len, unsigned int off, bool *same_page) -{ - struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; + if (!*same_page) { + if (IS_ENABLED(CONFIG_KMSAN)) + return false; + if (bv->bv_page + bv_end / PAGE_SIZE != page + off / PAGE_SIZE) + return false; + }
- if (!page_is_mergeable(bv, page, len, off, same_page)) - return false; bv->bv_len += len; - bio->bi_iter.bi_size += len; return true; }
@@ -972,7 +947,7 @@ static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio, return false; if (bv->bv_len + len > queue_max_segment_size(q)) return false; - return __bio_try_merge_page(bio, page, len, offset, same_page); + return bvec_try_merge_page(bv, page, len, offset, same_page); }
/** @@ -1001,8 +976,11 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio, return 0;
if (bio->bi_vcnt > 0) { - if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page)) + if (bio_try_merge_hw_seg(q, bio, page, len, offset, + same_page)) { + bio->bi_iter.bi_size += len; return len; + }
/* * If the queue doesn't support SG gaps and adding this segment @@ -1125,8 +1103,11 @@ int bio_add_page(struct bio *bio, struct page *page, return 0;
if (bio->bi_vcnt > 0 && - __bio_try_merge_page(bio, page, len, offset, &same_page)) + bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1], + page, len, offset, &same_page)) { + bio->bi_iter.bi_size += len; return len; + }
if (bio_full(bio, len)) return 0; @@ -1208,7 +1189,9 @@ static int bio_iov_add_page(struct bio *bio, struct page *page, return -EIO;
if (bio->bi_vcnt > 0 && - __bio_try_merge_page(bio, page, len, offset, &same_page)) { + bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1], + page, len, offset, &same_page)) { + bio->bi_iter.bi_size += len; if (same_page) bio_release_page(bio, page); return 0;