ext4: fix data integrity for ext4_sync_fs
Inode's data or non journaled quota may be written w/o jounral so we
_must_ send a barrier at the end of ext4_sync_fs. But it can be
skipped if journal commit will do it for us.
Also fix data integrity for nojournal mode.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 7c8e171..0f77c2e 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -69,6 +69,7 @@
static void ext4_clear_journal_err(struct super_block *sb,
struct ext4_super_block *es);
static int ext4_sync_fs(struct super_block *sb, int wait);
+static int ext4_sync_fs_nojournal(struct super_block *sb, int wait);
static int ext4_remount(struct super_block *sb, int *flags, char *data);
static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
static int ext4_unfreeze(struct super_block *sb);
@@ -1097,6 +1098,7 @@
.dirty_inode = ext4_dirty_inode,
.drop_inode = ext4_drop_inode,
.evict_inode = ext4_evict_inode,
+ .sync_fs = ext4_sync_fs_nojournal,
.put_super = ext4_put_super,
.statfs = ext4_statfs,
.remount_fs = ext4_remount,
@@ -4553,6 +4555,7 @@
{
int ret = 0;
tid_t target;
+ bool needs_barrier = false;
struct ext4_sb_info *sbi = EXT4_SB(sb);
trace_ext4_sync_fs(sb, wait);
@@ -4563,10 +4566,41 @@
* no dirty dquots
*/
dquot_writeback_dquots(sb, -1);
+ /*
+ * Data writeback is possible w/o journal transaction, so barrier must
+ * being sent at the end of the function. But we can skip it if
+ * transaction_commit will do it for us.
+ */
+ target = jbd2_get_latest_transaction(sbi->s_journal);
+ if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
+ !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
+ needs_barrier = true;
+
if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
if (wait)
- jbd2_log_wait_commit(sbi->s_journal, target);
+ ret = jbd2_log_wait_commit(sbi->s_journal, target);
}
+ if (needs_barrier) {
+ int err;
+ err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
+ if (!ret)
+ ret = err;
+ }
+
+ return ret;
+}
+
+static int ext4_sync_fs_nojournal(struct super_block *sb, int wait)
+{
+ int ret = 0;
+
+ trace_ext4_sync_fs(sb, wait);
+ flush_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
+ flush_workqueue(EXT4_SB(sb)->unrsv_conversion_wq);
+ dquot_writeback_dquots(sb, -1);
+ if (wait && test_opt(sb, BARRIER))
+ ret = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
+
return ret;
}