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>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 91c3873..42d8ce9 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3498,7 +3498,7 @@
map->m_flags |= EXT4_MAP_UNINIT;
}
- if (unlikely(EXT4_I(inode)->i_flags & EXT4_EOFBLOCKS_FL)) {
+ if (unlikely(ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))) {
if (unlikely(!eh->eh_entries)) {
EXT4_ERROR_INODE(inode,
"eh->eh_entries == 0 ee_block %d",
@@ -3509,7 +3509,7 @@
last_ex = EXT_LAST_EXTENT(eh);
if (map->m_lblk + ar.len > le32_to_cpu(last_ex->ee_block)
+ ext4_ext_get_actual_len(last_ex))
- EXT4_I(inode)->i_flags &= ~EXT4_EOFBLOCKS_FL;
+ ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
}
err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
if (err) {
@@ -3650,7 +3650,7 @@
* can proceed even if the new size is the same as i_size.
*/
if (new_size > i_size_read(inode))
- EXT4_I(inode)->i_flags |= EXT4_EOFBLOCKS_FL;
+ ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
}
}
@@ -3677,7 +3677,7 @@
* currently supporting (pre)allocate mode for extent-based
* files _only_
*/
- if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+ if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
return -EOPNOTSUPP;
/* preallocation to directories is currently not supported */
@@ -3922,7 +3922,7 @@
int error = 0;
/* fallback to generic here if not in extents fmt */
- if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+ if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
return generic_block_fiemap(inode, fieinfo, start, len,
ext4_get_block);