1 files changed, 22 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f2fb974ed8f0..9f08136b10c4 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6681,7 +6681,8 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
         return 0;
 }
 
-int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput)
+int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput,
+                                   int sync)
 {
         struct btrfs_inode *binode;
         struct inode *inode = NULL;
@@ -6703,7 +6704,26 @@ int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput)
         spin_unlock(&root->fs_info->delalloc_lock);
 
         if (inode) {
-                write_inode_now(inode, 0);
+                if (sync) {
+                        filemap_write_and_wait(inode->i_mapping);
+                        /*
+                         * We have to do this because compression doesn't
+                         * actually set PG_writeback until it submits the pages
+                         * for IO, which happens in an async thread, so we could
+                         * race and not actually wait for any writeback pages
+                         * because they've not been submitted yet.  Technically
+                         * this could still be the case for the ordered stuff
+                         * since the async thread may not have started to do its
+                         * work yet.  If this becomes the case then we need to
+                         * figure out a way to make sure that in writepage we
+                         * wait for any async pages to be submitted before
+                         * returning so that fdatawait does what its supposed to
+                         * do.
+                         */
+                        btrfs_wait_ordered_range(inode, 0, (u64)-1);
+                } else {
+                        filemap_flush(inode->i_mapping);
+                }
                 if (delay_iput)
                         btrfs_add_delayed_iput(inode);
                 else