ext4: Use bitops to read/modify EXT4_I(inode)->i_state

At several places we modify EXT4_I(inode)->i_state without holding
i_mutex (ext4_release_file, ext4_bmap, ext4_journalled_writepage,
ext4_do_update_inode, ...). These modifications are racy and we can
lose updates to i_state. So convert handling of i_state to use bitops
which are atomic.

Cc: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index 81415814b00b..46a4101e0aec 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -365,12 +365,12 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
          * happened after we started the migrate. We need to
          * fail the migrate
          */
-        if (!(EXT4_I(inode)->i_state & EXT4_STATE_EXT_MIGRATE)) {
+        if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
                 retval = -EAGAIN;
                 up_write(&EXT4_I(inode)->i_data_sem);
                 goto err_out;
         } else
-                EXT4_I(inode)->i_state &= ~EXT4_STATE_EXT_MIGRATE;
+                ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
         /*
          * We have the extent map build with the tmp inode.
          * Now copy the i_data across
@@ -533,7 +533,7 @@ int ext4_ext_migrate(struct inode *inode)
          * allocation.
          */
         down_read((&EXT4_I(inode)->i_data_sem));
-        EXT4_I(inode)->i_state |= EXT4_STATE_EXT_MIGRATE;
+        ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
         up_read((&EXT4_I(inode)->i_data_sem));
 
         handle = ext4_journal_start(inode, 1);