Btrfs: add helper btrfs_fdatawrite_range

To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 2 insertions, 22 deletions

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index ac734ec4cc20..1401b1af4f06 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -725,30 +725,10 @@ int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 	/* start IO across the range first to instantiate any delalloc
 	 * extents
 	 */
-	ret = filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+	ret = btrfs_fdatawrite_range(inode, start, orig_end);
 	if (ret)
 		return ret;
-	/*
-	 * So with compression we will find and lock a dirty page and clear the
-	 * first one as dirty, setup an async extent, and immediately return
-	 * with the entire range locked but with nobody actually marked with
-	 * writeback.  So we can't just filemap_write_and_wait_range() and
-	 * expect it to work since it will just kick off a thread to do the
-	 * actual work.  So we need to call filemap_fdatawrite_range _again_
-	 * since it will wait on the page lock, which won't be unlocked until
-	 * after the pages have been marked as writeback and so we're good to go
-	 * from there.  We have to do this otherwise we'll miss the ordered
-	 * extents and that results in badness.  Please Josef, do not think you
-	 * know better and pull this out at some point in the future, it is
-	 * right and you are wrong.
-	 */
-	if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
-		     &BTRFS_I(inode)->runtime_flags)) {
-		ret = filemap_fdatawrite_range(inode->i_mapping, start,
-					       orig_end);
-		if (ret)
-			return ret;
-	}
+
 	ret = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 	if (ret)
 		return ret;