When data integrity operation happens (sync, fsync, fdatasync calls) writeback control is set to WB_SYNC_ALL. In that case all write requests are marked with WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE) indicating that caller is waiting for completion and block layer or block device should prioritize the IO avoiding any possible delays.
But mpage writeback path ignores marking requests as WRITE_SYNC. This patch fixes this. Signed-off-by: Roman Pen <r.peni...@gmail.com> Reviewed-by: Jan Kara <j...@suse.cz> Cc: Jens Axboe <ax...@kernel.dk> Cc: Tejun Heo <t...@kernel.org> Cc: Andrew Morton <a...@linux-foundation.org> Cc: linux-fsde...@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- fs/mpage.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/fs/mpage.c b/fs/mpage.c index 4979ffa..4e0af5a 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -462,6 +462,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc, struct buffer_head map_bh; loff_t i_size = i_size_read(inode); int ret = 0; + int wr = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); if (page_has_buffers(page)) { struct buffer_head *head = page_buffers(page); @@ -570,7 +571,7 @@ page_is_mapped: * This page will go to BIO. Do we need to send this BIO off first? */ if (bio && mpd->last_block_in_bio != blocks[0] - 1) - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); alloc_new: if (bio == NULL) { @@ -587,7 +588,7 @@ alloc_new: */ length = first_unmapped << blkbits; if (bio_add_page(bio, page, length, 0) < length) { - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); goto alloc_new; } @@ -620,7 +621,7 @@ alloc_new: set_page_writeback(page); unlock_page(page); if (boundary || (first_unmapped != blocks_per_page)) { - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); if (boundary_block) { write_boundary_block(boundary_bdev, boundary_block, 1 << blkbits); @@ -632,7 +633,7 @@ alloc_new: confused: if (bio) - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); if (mpd->use_writepage) { ret = mapping->a_ops->writepage(page, wbc); @@ -688,8 +689,11 @@ mpage_writepages(struct address_space *mapping, }; ret = write_cache_pages(mapping, wbc, __mpage_writepage, &mpd); - if (mpd.bio) - mpage_bio_submit(WRITE, mpd.bio); + if (mpd.bio) { + int wr = (wbc->sync_mode == WB_SYNC_ALL ? + WRITE_SYNC : WRITE); + mpage_bio_submit(wr, mpd.bio); + } } blk_finish_plug(&plug); return ret; @@ -706,8 +710,11 @@ int mpage_writepage(struct page *page, get_block_t get_block, .use_writepage = 0, }; int ret = __mpage_writepage(page, wbc, &mpd); - if (mpd.bio) - mpage_bio_submit(WRITE, mpd.bio); + if (mpd.bio) { + int wr = (wbc->sync_mode == WB_SYNC_ALL ? + WRITE_SYNC : WRITE); + mpage_bio_submit(wr, mpd.bio); + } return ret; } EXPORT_SYMBOL(mpage_writepage); -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/