[XFS] add generic btree types
Add generic union types for btree pointers, keys and records. The generic
btree pointer contains either a 32 and 64bit big endian scalar for short
and long form btrees, and the key and record contain the relevant type for
each possible btree.
Split out from a bigger patch from Dave Chinner and simplified a little
further.
SGI-PV: 985583
SGI-Modid: xfs-linux-melb:xfs-kern:32178a
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>
diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index d30ee74..428e81f 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -80,6 +80,31 @@
} xfs_btree_block_t;
/*
+ * Generic key, ptr and record wrapper structures.
+ *
+ * These are disk format structures, and are converted where necessary
+ * by the btree specific code that needs to interpret them.
+ */
+union xfs_btree_ptr {
+ __be32 s; /* short form ptr */
+ __be64 l; /* long form ptr */
+};
+
+union xfs_btree_key {
+ xfs_bmbt_key_t bmbt;
+ xfs_bmdr_key_t bmbr; /* bmbt root block */
+ xfs_alloc_key_t alloc;
+ xfs_inobt_key_t inobt;
+};
+
+union xfs_btree_rec {
+ xfs_bmbt_rec_t bmbt;
+ xfs_bmdr_rec_t bmbr; /* bmbt root block */
+ xfs_alloc_rec_t alloc;
+ xfs_inobt_rec_t inobt;
+};
+
+/*
* For logging record fields.
*/
#define XFS_BB_MAGIC 0x01