shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 12:17:12 +09:00
Code Issues Packages Projects Releases Wiki Activity

f2fs: fix race in between GC and atomic open

Browse Source 
Thread					GC thread
- f2fs_ioc_start_atomic_write
 - get_dirty_pages
 - filemap_write_and_wait_range
					- f2fs_gc
					 - do_garbage_collect
					  - gc_data_segment
					   - move_data_page
					    - f2fs_is_atomic_file
					    - set_page_dirty
 - set_inode_flag(, FI_ATOMIC_FILE)

Dirty data page can still be generated by GC in race condition as
above call stack.

This patch adds fi->dio_rwsem[WRITE] in f2fs_ioc_start_atomic_write
to avoid such race.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu
2018-04-17 17:51:28 +08:00
committed by Jaegeuk Kim
parent 0d17eb90b5
commit 9d77ded0a7
1 changed files with 3 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
fs/f2fs/file.c
View File

@@ -1676,6 +1676,8 @@ static int f2fs_ioc_start_atomic_write(struct file *filp)
inode_lock(inode); inode_lock(inode);
down_write(&F2FS_I(inode)->dio_rwsem[WRITE]);
if (f2fs_is_atomic_file(inode)) if (f2fs_is_atomic_file(inode))
goto out; goto out;
@@ -1705,6 +1707,7 @@ inc_stat:
stat_inc_atomic_write(inode); stat_inc_atomic_write(inode);
stat_update_max_atomic_write(inode); stat_update_max_atomic_write(inode);
out: out:
up_write(&F2FS_I(inode)->dio_rwsem[WRITE]);
inode_unlock(inode); inode_unlock(inode);
mnt_drop_write_file(filp); mnt_drop_write_file(filp);
return ret; return ret;