From 9411b96bd71341d0c9fd08516562559fe76170fc Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Tue, 12 Jul 2022 08:32:54 -0700 Subject: [PATCH] block: ensure iov_iter advances for added pages [ Upstream commit 1b3ebd46b03907fa04e3723cafb6ae85c7e2889b ] There are cases where a bio may not accept additional pages, and the iov needs to advance to the last data length that was accepted. The zone append used to handle this correctly, but was inadvertently broken when the setup was made common with the normal r/w case. Fixes: 956b6e8353966 ("block: use bio_add_page in bio_iov_iter_get_pages") Fixes: 6f5a0eb93d937 ("block/bio: remove duplicate append pages code") Signed-off-by: Keith Busch Link: https://lore.kernel.org/r/20220712153256.2202024-1-kbusch@fb.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/bio.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/block/bio.c b/block/bio.c index 0dd7aa1797f61..ba9120d4fe499 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1123,6 +1123,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) ssize_t size, left; unsigned len, i; size_t offset; + int ret = 0; /* * Move page array up in the allocated memory for the bio vecs as far as @@ -1138,7 +1139,6 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) for (left = size, i = 0; left > 0; left -= len, i++) { struct page *page = pages[i]; - int ret; len = min_t(size_t, PAGE_SIZE - offset, left); if (bio_op(bio) == REQ_OP_ZONE_APPEND) @@ -1149,13 +1149,13 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) if (ret) { bio_put_pages(pages + i, left, offset); - return ret; + break; } offset = 0; } - iov_iter_advance(iter, size); - return 0; + iov_iter_advance(iter, size - left); + return ret; } /** -- 2.39.5