[XFS] implement generic xfs_btree_split

Make the btree split code generic. Based on a patch from David Chinner
with lots of changes to follow the original btree implementations more
closely. While this loses some of the generic helper routines for
inserting/moving/removing records it also solves some of the one off bugs
in the original code and makes it easier to verify.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32198a

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, 8 insertions, 0 deletions

diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index 7cde287b5c9c..354a6656fad5 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -187,6 +187,12 @@ struct xfs_btree_ops {
         /* cursor operations */
         struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
 
+        /* block allocation / freeing */
+        int     (*alloc_block)(struct xfs_btree_cur *cur,
+                               union xfs_btree_ptr *start_bno,
+                               union xfs_btree_ptr *new_bno,
+                               int length, int *stat);
+
         /* update last record information */
         void    (*update_lastrec)(struct xfs_btree_cur *cur,
                                   struct xfs_btree_block *block,
@@ -535,6 +541,8 @@ int xfs_btree_updkey(struct xfs_btree_cur *, union xfs_btree_key *, int);
 int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
 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 *);
 
 /*
  * Helpers.