[XFS] implement generic xfs_btree_rshift

Make the btree right shift 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:32196a

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, 7 insertions, 0 deletions

diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index c3bfa5556c19..04311dbeff19 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -533,6 +533,7 @@ int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
 int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
 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_rshift(struct xfs_btree_cur *, int, int *);
 
 /*
  * Helpers.
@@ -542,6 +543,12 @@ static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block)
         return be16_to_cpu(block->bb_numrecs);
 }
 
+static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
+                __uint16_t numrecs)
+{
+        block->bb_numrecs = cpu_to_be16(numrecs);
+}
+
 static inline int xfs_btree_get_level(struct xfs_btree_block *block)
 {
         return be16_to_cpu(block->bb_level);