>From 8e0ae2a449f996e0ea5ad865d3147ee6758743aa Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 29 Mar 2013 18:05:01 +0100 Subject: [PATCH] direct-io: Submit bio after boundary buffer is added to it Currently, dio_send_cur_page() submits bio before current page and cached sdio->cur_page is added to the bio if sdio->boundary is set. This is actually wrong because sdio->boundary means the current buffer is the last one before metadata needs to be read. So we should rather submit the bio after the current page is added to it. Reported-by: Kazuya Mio Signed-off-by: Jan Kara --- fs/direct-io.c | 28 +++++++++++----------------- 1 files changed, 11 insertions(+), 17 deletions(-) diff --git a/fs/direct-io.c b/fs/direct-io.c index e666854..c57add7 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -672,12 +672,6 @@ static inline int dio_send_cur_page(struct dio *dio, struct dio_submit *sdio, if (sdio->final_block_in_bio != sdio->cur_page_block || cur_offset != bio_next_offset) dio_bio_submit(dio, sdio); - /* - * Submit now if the underlying fs is about to perform a - * metadata read - */ - else if (sdio->boundary) - dio_bio_submit(dio, sdio); } if (sdio->bio == NULL) { @@ -737,16 +731,6 @@ submit_page_section(struct dio *dio, struct dio_submit *sdio, struct page *page, sdio->cur_page_block + (sdio->cur_page_len >> sdio->blkbits) == blocknr) { sdio->cur_page_len += len; - - /* - * If sdio->boundary then we want to schedule the IO now to - * avoid metadata seeks. - */ - if (sdio->boundary) { - ret = dio_send_cur_page(dio, sdio, map_bh); - page_cache_release(sdio->cur_page); - sdio->cur_page = NULL; - } goto out; } @@ -758,7 +742,7 @@ submit_page_section(struct dio *dio, struct dio_submit *sdio, struct page *page, page_cache_release(sdio->cur_page); sdio->cur_page = NULL; if (ret) - goto out; + return ret; } page_cache_get(page); /* It is in dio */ @@ -768,6 +752,16 @@ submit_page_section(struct dio *dio, struct dio_submit *sdio, struct page *page, sdio->cur_page_block = blocknr; sdio->cur_page_fs_offset = sdio->block_in_file << sdio->blkbits; out: + /* + * If sdio->boundary then we want to schedule the IO now to + * avoid metadata seeks. + */ + if (sdio->boundary) { + ret = dio_send_cur_page(dio, sdio, map_bh); + dio_bio_submit(dio, sdio); + page_cache_release(sdio->cur_page); + sdio->cur_page = NULL; + } return ret; } -- 1.7.1