4 files changed, 22 insertions, 4 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2775e270881e..0079b60b18f3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -610,6 +610,7 @@ struct btrfs_fs_info {
         struct list_head dead_roots;
 
         atomic_t nr_async_submits;
+        atomic_t async_submit_draining;
         atomic_t nr_async_bios;
         atomic_t tree_log_writers;
         atomic_t tree_log_commit;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 45bc3132b054..45b4f7285275 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -460,6 +460,13 @@ int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
         async->submit_bio_hook = submit_bio_hook;
         async->work.func = run_one_async_submit;
         async->work.flags = 0;
+
+        while(atomic_read(&fs_info->async_submit_draining) &&
+              atomic_read(&fs_info->nr_async_submits)) {
+                wait_event(fs_info->async_submit_wait,
+                           (atomic_read(&fs_info->nr_async_submits) == 0));
+        }
+
         atomic_inc(&fs_info->nr_async_submits);
         btrfs_queue_worker(&fs_info->workers, &async->work);
 
@@ -495,11 +502,8 @@ static int __btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
                                  int mirror_num)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
-        u64 offset;
         int ret;
 
-        offset = bio->bi_sector << 9;
-
         /*
          * when we're called for a write, we're already in the async
          * submission context.  Just jump into btrfs_map_bio
@@ -1360,6 +1364,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         INIT_LIST_HEAD(&fs_info->space_info);
         btrfs_mapping_init(&fs_info->mapping_tree);
         atomic_set(&fs_info->nr_async_submits, 0);
+        atomic_set(&fs_info->async_submit_draining, 0);
         atomic_set(&fs_info->nr_async_bios, 0);
         atomic_set(&fs_info->throttles, 0);
         atomic_set(&fs_info->throttle_gen, 0);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4516fbf01671..404704d26822 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3440,13 +3440,24 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root)
                         list_del_init(&binode->delalloc_inodes);
                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
                 if (inode) {
-                        filemap_write_and_wait(inode->i_mapping);
+                        filemap_flush(inode->i_mapping);
                         iput(inode);
                 }
                 cond_resched();
                 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
         }
         spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
+
+        /* the filemap_flush will queue IO into the worker threads, but
+         * we have to make sure the IO is actually started and that
+         * ordered extents get created before we return
+         */
+        atomic_inc(&root->fs_info->async_submit_draining);
+        while(atomic_read(&root->fs_info->nr_async_submits)) {
+                wait_event(root->fs_info->async_submit_wait,
+                   (atomic_read(&root->fs_info->nr_async_submits) == 0));
+        }
+        atomic_dec(&root->fs_info->async_submit_draining);
         return 0;
 }
 
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 51f113119b25..f63cf7621a01 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1038,6 +1038,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
                 return -EIO;
         }
 
+        filemap_write_and_wait(bdev->bd_inode->i_mapping);
         mutex_lock(&root->fs_info->volume_mutex);
 
         trans = btrfs_start_transaction(root, 1);