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/mballoc.c b/fs/ext4/mballoc.c
index e5dcdc9bd56b..0bdc0188e5e2 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2006,7 +2006,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
         sbi = EXT4_SB(sb);
         ngroups = ext4_get_groups_count(sb);
         /* non-extent files are limited to low blocks/groups */
-        if (!(EXT4_I(ac->ac_inode)->i_flags & EXT4_EXTENTS_FL))
+        if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)))
                 ngroups = sbi->s_blockfile_groups;
 
         BUG_ON(ac->ac_status == AC_STATUS_FOUND);
@@ -3171,7 +3171,7 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac)
                         continue;
 
                 /* non-extent files can't have physical blocks past 2^32 */
-                if (!(EXT4_I(ac->ac_inode)->i_flags & EXT4_EXTENTS_FL) &&
+                if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)) &&
                         pa->pa_pstart + pa->pa_len > EXT4_MAX_BLOCK_FILE_PHYS)
                         continue;