038d06984f
Atomic write needs page cache to cache data of transaction, direct IO should never be allowed in atomic write, detect and deny it when open atomic write file. Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>