ext4: Use bitops to read/modify i_flags in struct ext4_inode_info

At several places we modify EXT4_I(inode)->i_flags without holding
i_mutex (ext4_do_update_inode, ...). These modifications are racy and
we can lose updates to i_flags. So convert handling of i_flags to use
bitops which are atomic.

https://bugzilla.kernel.org/show_bug.cgi?id=15792

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index d0776e410f34..5313ae4cda2d 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -66,7 +66,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
          * is smaller than s_maxbytes, which is for extent-mapped files.
          */
 
-        if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) {
+        if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
                 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
                 size_t length = iov_length(iov, nr_segs);