diff options
| author | Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> | 2008-09-02 14:35:40 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-09-02 19:21:37 -0700 |
| commit | 6ccfa806a9cfbbf1cd43d5b6aa47ef2c0eb518fd (patch) | |
| tree | dd3f17e1aebc802b147627a4151add363f39b77c /mm/truncate.c | |
| parent | 344c790e3821dac37eb742ddd0b611a300f78b9a (diff) | |
VFS: fix dio write returning EIO when try_to_release_page fails
Dio write returns EIO when try_to_release_page fails because bh is
still referenced.
The patch
commit 3f31fddfa26b7594b44ff2b34f9a04ba409e0f91
Author: Mingming Cao <cmm@us.ibm.com>
Date: Fri Jul 25 01:46:22 2008 -0700
jbd: fix race between free buffer and commit transaction
was merged into 2.6.27-rc1, but I noticed that this patch is not enough
to fix the race.
I did fsstress test heavily to 2.6.27-rc1, and found that dio write still
sometimes got EIO through this test.
The patch above fixed race between freeing buffer(dio) and committing
transaction(jbd) but I discovered that there is another race, freeing
buffer(dio) and ext3/4_ordered_writepage.
: background_writeout()
->write_cache_pages()
->ext3_ordered_writepage()
walk_page_buffers() -> take a bh ref
block_write_full_page() -> unlock_page
: <- end_page_writeback
: <- race! (dio write->try_to_release_page fails)
walk_page_buffers() ->release a bh ref
ext3_ordered_writepage holds bh ref and does unlock_page remaining
taking a bh ref, so this causes the race and failure of
try_to_release_page.
To fix this race, I used the approach of falling back to buffered
writes if try_to_release_page() fails on a page.
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/truncate.c')
| -rw-r--r-- | mm/truncate.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/truncate.c b/mm/truncate.c index 250505091d37..6650c1d878b4 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -380,7 +380,7 @@ static int do_launder_page(struct address_space *mapping, struct page *page) * Any pages which are found to be mapped into pagetables are unmapped prior to * invalidation. * - * Returns -EIO if any pages could not be invalidated. + * Returns -EBUSY if any pages could not be invalidated. */ int invalidate_inode_pages2_range(struct address_space *mapping, pgoff_t start, pgoff_t end) @@ -440,7 +440,7 @@ int invalidate_inode_pages2_range(struct address_space *mapping, ret2 = do_launder_page(mapping, page); if (ret2 == 0) { if (!invalidate_complete_page2(mapping, page)) - ret2 = -EIO; + ret2 = -EBUSY; } if (ret2 < 0) ret = ret2; |