[XFS] implement semi-generic xfs_btree_new_root

From: Dave Chinner <dgc@sgi.com>

Add a xfs_btree_new_root helper for the alloc and ialloc btrees. The bmap
btree needs it's own version and is not converted.

[hch: split out from bigger patch and minor adaptions]

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32200a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index 354a6656fad5..18015392feb0 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -187,6 +187,10 @@ struct xfs_btree_ops {
         /* cursor operations */
         struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
 
+        /* update btree root pointer */
+        void    (*set_root)(struct xfs_btree_cur *cur,
+                                union xfs_btree_ptr *nptr, int level_change);
+
         /* block allocation / freeing */
         int     (*alloc_block)(struct xfs_btree_cur *cur,
                                union xfs_btree_ptr *start_bno,
@@ -543,6 +547,7 @@ int xfs_btree_lshift(struct xfs_btree_cur *, int, int *);
 int xfs_btree_rshift(struct xfs_btree_cur *, int, int *);
 int xfs_btree_split(struct xfs_btree_cur *, int, union xfs_btree_ptr *,
                 union xfs_btree_key *, struct xfs_btree_cur **, int *);
+int xfs_btree_new_root(struct xfs_btree_cur *, int *);
 
 /*
  * Helpers.