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, 2 insertions, 2 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 52618d5a1773..7f6b5826d5a6 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -492,7 +492,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent,
 
         if (S_ISDIR(mode) &&
             ((parent == sb->s_root->d_inode) ||
-             (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL))) {
+             (ext4_test_inode_flag(parent, EXT4_INODE_TOPDIR)))) {
                 int best_ndir = inodes_per_group;
                 int ret = -1;
 
@@ -1038,7 +1038,7 @@ got:
         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
                 /* set extent flag only for directory, file and normal symlink*/
                 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
-                        EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
+                        ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
                         ext4_ext_tree_init(handle, inode);
                 }
         }