ext3: Check return value of blkdev_issue_flush()

blkdev_issue_flush() can fail. Make sure the error gets properly propagated.
Signed-off-by: NJan Kara <jack@suse.cz>

fs/ext3/fsync.c

@@ -92,8 +92,13 @@ int ext3_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	 * disk caches manually so that data really is on persistent
 	 * storage
 	 */
-	if (needs_barrier)
-		blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
+	if (needs_barrier) {
+		int err;
+
+		err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
+		if (!ret)
+			ret = err;
+	}
 out:
 	trace_ext3_sync_file_exit(inode, ret);
 	return ret;