diff options
| author | Qiuyang Sun <sunqiuyang@huawei.com> | 2017-05-18 11:06:45 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2017-07-04 02:11:35 -0700 |
| commit | 5a3a2d83cda82df7f8c306df85647d2c368e829a (patch) | |
| tree | 788e4bf15eb8ea3dd011e3202c8e2b9bd9aa59f9 /fs/f2fs/data.c | |
| parent | 72fdbe2efe3e42a54e268d2ee2a8c0828d3996e7 (diff) | |
| download | linux-5a3a2d83cda82df7f8c306df85647d2c368e829a.tar.bz2 | |
f2fs: dax: fix races between page faults and truncating pages
Currently in F2FS, page faults and operations that truncate the pagecahe
or data blocks, are completely unsynchronized. This can result in page
fault faulting in a page into a range that we are changing after
truncating, and thus we can end up with a page mapped to disk blocks that
will be shortly freed. Filesystem corruption will shortly follow.
This patch fixes the problem by creating new rw semaphore i_mmap_sem in
f2fs_inode_info and grab it for functions removing blocks from extent tree
and for read over page faults. The mechanism is similar to that in ext4.
Signed-off-by: Qiuyang Sun <sunqiuyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/data.c')
| -rw-r--r-- | fs/f2fs/data.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 2ed90f5db832..7d3af48d34a9 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1801,8 +1801,10 @@ static void f2fs_write_failed(struct address_space *mapping, loff_t to) loff_t i_size = i_size_read(inode); if (to > i_size) { + down_write(&F2FS_I(inode)->i_mmap_sem); truncate_pagecache(inode, i_size); truncate_blocks(inode, i_size, true); + up_write(&F2FS_I(inode)->i_mmap_sem); } } |