From 07173c3ec276cbb18dc0e0687d37d310e98a1480 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 15 Feb 2019 19:13:20 +0800 Subject: block: enable multipage bvecs This patch pulls the trigger for multi-page bvecs. Reviewed-by: Omar Sandoval Signed-off-by: Ming Lei Signed-off-by: Jens Axboe --- block/bio.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) (limited to 'block/bio.c') diff --git a/block/bio.c b/block/bio.c index 968b12fea564..83a2dfa417ca 100644 --- a/block/bio.c +++ b/block/bio.c @@ -753,6 +753,8 @@ EXPORT_SYMBOL(bio_add_pc_page); * @page: page to add * @len: length of the data to add * @off: offset of the data in @page + * @same_page: if %true only merge if the new data is in the same physical + * page as the last segment of the bio. * * Try to add the data at @page + @off to the last bvec of @bio. This is a * a useful optimisation for file systems with a block size smaller than the @@ -761,19 +763,25 @@ EXPORT_SYMBOL(bio_add_pc_page); * Return %true on success or %false on failure. */ bool __bio_try_merge_page(struct bio *bio, struct page *page, - unsigned int len, unsigned int off) + 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]; + phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + + bv->bv_offset + bv->bv_len - 1; + phys_addr_t page_addr = page_to_phys(page); - if (page == bv->bv_page && off == bv->bv_offset + bv->bv_len) { - bv->bv_len += len; - bio->bi_iter.bi_size += len; - return true; - } + if (vec_end_addr + 1 != page_addr + off) + return false; + if (same_page && (vec_end_addr & PAGE_MASK) != page_addr) + return false; + + bv->bv_len += len; + bio->bi_iter.bi_size += len; + return true; } return false; } @@ -819,7 +827,7 @@ EXPORT_SYMBOL_GPL(__bio_add_page); int bio_add_page(struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { - if (!__bio_try_merge_page(bio, page, len, offset)) { + if (!__bio_try_merge_page(bio, page, len, offset, false)) { if (bio_full(bio)) return 0; __bio_add_page(bio, page, len, offset); -- cgit v1.2.3