Btrfs: deal with DIO bios that span more than one ordered extent

The new DIO bio splitting code has problems when the bio
spans more than one ordered extent.  This will happen as the
generic DIO code merges our get_blocks calls together into
a bigger single bio.

This fixes things by walking forward in the ordered extent
code finding all the overlapping ordered extents and completing them
all at once.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 19 insertions, 4 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 6df921f..0f34cae 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5602,15 +5602,18 @@ static void btrfs_endio_direct_write(struct bio *bio, int err)
 	struct btrfs_trans_handle *trans;
 	struct btrfs_ordered_extent *ordered = NULL;
 	struct extent_state *cached_state = NULL;
+	u64 ordered_offset = dip->logical_offset;
+	u64 ordered_bytes = dip->bytes;
 	int ret;
 
 	if (err)
 		goto out_done;
-
-	ret = btrfs_dec_test_ordered_pending(inode, &ordered,
-					     dip->logical_offset, dip->bytes);
+again:
+	ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
+						   &ordered_offset,
+						   ordered_bytes);
 	if (!ret)
-		goto out_done;
+		goto out_test;
 
 	BUG_ON(!ordered);
 
@@ -5670,8 +5673,20 @@ out_unlock:
 out:
 	btrfs_delalloc_release_metadata(inode, ordered->len);
 	btrfs_end_transaction(trans, root);
+	ordered_offset = ordered->file_offset + ordered->len;
 	btrfs_put_ordered_extent(ordered);
 	btrfs_put_ordered_extent(ordered);
+
+out_test:
+	/*
+	 * our bio might span multiple ordered extents.  If we haven't
+	 * completed the accounting for the whole dio, go back and try again
+	 */
+	if (ordered_offset < dip->logical_offset + dip->bytes) {
+		ordered_bytes = dip->logical_offset + dip->bytes -
+			ordered_offset;
+		goto again;
+	}
 out_done:
 	bio->bi_private = dip->private;