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/move_extent.c b/fs/ext4/move_extent.c
index b8b8ea1ceda8..3a6c92ac131c 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -977,11 +977,11 @@ mext_check_arguments(struct inode *orig_inode,
         }
 
         /* Ext4 move extent supports only extent based file */
-        if (!(EXT4_I(orig_inode)->i_flags & EXT4_EXTENTS_FL)) {
+        if (!(ext4_test_inode_flag(orig_inode, EXT4_INODE_EXTENTS))) {
                 ext4_debug("ext4 move extent: orig file is not extents "
                         "based file [ino:orig %lu]\n", orig_inode->i_ino);
                 return -EOPNOTSUPP;
-        } else if (!(EXT4_I(donor_inode)->i_flags & EXT4_EXTENTS_FL)) {
+        } else if (!(ext4_test_inode_flag(donor_inode, EXT4_INODE_EXTENTS))) {
                 ext4_debug("ext4 move extent: donor file is not extents "
                         "based file [ino:donor %lu]\n", donor_inode->i_ino);
                 return -EOPNOTSUPP;