[XFS] cleanup defintions of BMBT_*BITLEN macros

The BMBT_*BITLEN are currently defined in a complicated way depending on
XFS_NATIVE_HOST. But if all the macros are expanded they (obviously)
expand to the same value for both cases.

This patch defines the macros in the most simple way and updates the
comment describing them to remove outdated bits.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29320a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

fs/xfs/xfs_bmap_btree.h

@@ -35,45 +35,16 @@ typedef struct xfs_bmdr_block {
 
 /*
  * Bmap btree record and extent descriptor.
- * For 32-bit kernels,
- *  l0:31 is an extent flag (value 1 indicates non-normal).
- *  l0:0-30 and l1:9-31 are startoff.
- *  l1:0-8, l2:0-31, and l3:21-31 are startblock.
- *  l3:0-20 are blockcount.
- * For 64-bit kernels,
  *  l0:63 is an extent flag (value 1 indicates non-normal).
  *  l0:9-62 are startoff.
  *  l0:0-8 and l1:21-63 are startblock.
  *  l1:0-20 are blockcount.
  */
-
-#ifndef XFS_NATIVE_HOST
-
-#define BMBT_TOTAL_BITLEN	128	/* 128 bits, 16 bytes */
-#define BMBT_EXNTFLAG_BITOFF	0
 #define BMBT_EXNTFLAG_BITLEN	1
-#define BMBT_STARTOFF_BITOFF	(BMBT_EXNTFLAG_BITOFF + BMBT_EXNTFLAG_BITLEN)
 #define BMBT_STARTOFF_BITLEN	54
-#define BMBT_STARTBLOCK_BITOFF	(BMBT_STARTOFF_BITOFF + BMBT_STARTOFF_BITLEN)
 #define BMBT_STARTBLOCK_BITLEN	52
-#define BMBT_BLOCKCOUNT_BITOFF	\
-	(BMBT_STARTBLOCK_BITOFF + BMBT_STARTBLOCK_BITLEN)
-#define BMBT_BLOCKCOUNT_BITLEN	(BMBT_TOTAL_BITLEN - BMBT_BLOCKCOUNT_BITOFF)
-
-#else
-
-#define BMBT_TOTAL_BITLEN	128	/* 128 bits, 16 bytes */
-#define BMBT_EXNTFLAG_BITOFF	63
-#define BMBT_EXNTFLAG_BITLEN	1
-#define BMBT_STARTOFF_BITOFF	(BMBT_EXNTFLAG_BITOFF - BMBT_STARTOFF_BITLEN)
-#define BMBT_STARTOFF_BITLEN	54
-#define BMBT_STARTBLOCK_BITOFF	85 /* 128 - 43 (other 9 is in first word) */
-#define BMBT_STARTBLOCK_BITLEN	52
-#define BMBT_BLOCKCOUNT_BITOFF	64 /* Start of second 64 bit container */
 #define BMBT_BLOCKCOUNT_BITLEN	21
 
-#endif /* XFS_NATIVE_HOST */
-
 
 #define BMBT_USE_64	1