1 files changed, 30 insertions, 2 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index bf0345577672..9721d100caf1 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -474,10 +474,35 @@ static int do_bio_filebacked(struct loop_device *lo, struct bio *bio)
         int ret;
 
         pos = ((loff_t) bio->bi_sector << 9) + lo->lo_offset;
-        if (bio_rw(bio) == WRITE)
+
+        if (bio_rw(bio) == WRITE) {
+                int barrier = bio_barrier(bio);
+                struct file *file = lo->lo_backing_file;
+
+                if (barrier) {
+                        if (unlikely(!file->f_op->fsync)) {
+                                ret = -EOPNOTSUPP;
+                                goto out;
+                        }
+
+                        ret = vfs_fsync(file, file->f_path.dentry, 0);
+                        if (unlikely(ret)) {
+                                ret = -EIO;
+                                goto out;
+                        }
+                }
+
                 ret = lo_send(lo, bio, pos);
-        else
+
+                if (barrier && !ret) {
+                        ret = vfs_fsync(file, file->f_path.dentry, 0);
+                        if (unlikely(ret))
+                                ret = -EIO;
+                }
+        } else
                 ret = lo_receive(lo, bio, lo->lo_blocksize, pos);
+
+out:
         return ret;
 }
 
@@ -826,6 +851,9 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
         lo->lo_queue->queuedata = lo;
         lo->lo_queue->unplug_fn = loop_unplug;
 
+        if (!(lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync)
+                blk_queue_ordered(lo->lo_queue, QUEUE_ORDERED_DRAIN, NULL);
+
         set_capacity(lo->lo_disk, size);
         bd_set_size(bdev, size << 9);