xfs: use ->t_dfops in cancel cow blocks operation

Use ->t_dfops of the transaction from the caller. Reset it before we
return to avoid leaks of local stack memory.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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 90457c2a7569e887d2870b6925c8835e8ad5deff..8ea4ba0e45d8bd36d89d86717b08cb5a21bb20b9 100644 (file)
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -490,6 +490,7 @@ xfs_reflink_cancel_cow_blocks(
        struct xfs_iext_cursor          icur;
        xfs_fsblock_t                   firstfsb;
        struct xfs_defer_ops            dfops;
+       struct xfs_defer_ops            *odfops = (*tpp)->t_dfops;
        int                             error = 0;
 
        if (!xfs_is_reflink_inode(ip))
@@ -517,23 +518,24 @@ xfs_reflink_cancel_cow_blocks(
                                break;
                } else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) {
                        xfs_defer_init(&dfops, &firstfsb);
+                       (*tpp)->t_dfops = &dfops;
 
                        /* Free the CoW orphan record. */
                        error = xfs_refcount_free_cow_extent(ip->i_mount,
-                                       &dfops, del.br_startblock,
+                                       (*tpp)->t_dfops, del.br_startblock,
                                        del.br_blockcount);
                        if (error)
                                break;
 
-                       xfs_bmap_add_free(ip->i_mount, &dfops,
+                       xfs_bmap_add_free(ip->i_mount, (*tpp)->t_dfops,
                                        del.br_startblock, del.br_blockcount,
                                        NULL);
 
                        /* Roll the transaction */
-                       xfs_defer_ijoin(&dfops, ip);
-                       error = xfs_defer_finish(tpp, &dfops);
+                       xfs_defer_ijoin((*tpp)->t_dfops, ip);
+                       error = xfs_defer_finish(tpp, (*tpp)->t_dfops);
                        if (error) {
-                               xfs_defer_cancel(&dfops);
+                               xfs_defer_cancel((*tpp)->t_dfops);
                                break;
                        }
 
@@ -558,7 +560,7 @@ next_extent:
        /* clear tag if cow fork is emptied */
        if (!ifp->if_bytes)
                xfs_inode_clear_cowblocks_tag(ip);
-
+       (*tpp)->t_dfops = odfops;
        return error;
 }