xfs: fix double ijoin in xfs_reflink_clear_inode_flag()

xfs_reflink_clear_inode_flag double-joins an inode to a transaction,
which is not allowed.  Fix that and document that the caller must have
already joined it.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
[darrick: edit out trace for nonexistent ASSERT]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index bce2b53..12d441a 100644 (file)
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1553,7 +1553,12 @@ next:
        return 0;
 }
 
-/* Clear the inode reflink flag if there are no shared extents. */
+/*
+ * Clear the inode reflink flag if there are no shared extents.
+ *
+ * The caller is responsible for joining the inode to the transaction passed in.
+ * The inode will be joined to the transaction that is returned to the caller.
+ */
 int
 xfs_reflink_clear_inode_flag(
        struct xfs_inode        *ip,
@@ -1572,7 +1577,6 @@ xfs_reflink_clear_inode_flag(
         * We didn't find any shared blocks so turn off the reflink flag.
         * First, get rid of any leftover CoW mappings.
         */
-       xfs_trans_ijoin(*tpp, ip, 0);
        error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF, true);
        if (error)
                return error;