[XFS] Remove the BPCSHIFT and NB* based macros from XFS.

The BPCSHIFT based macros, btoc*, ctob*, offtoc* and ctooff are either not
used or don't need to be used. The NDPP, NDPP, NBBY macros don't need to
be used but instead are replaced directly by PAGE_SIZE and PAGE_CACHE_SIZE
where appropriate. Initial patch and motivation from Nicolas Kaiser.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30096a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

2 files changed, 5 insertions, 32 deletions

diff --git a/fs/xfs/linux-2.6/xfs_linux.h b/fs/xfs/linux-2.6/xfs_linux.h
index 9bf4f7e965c7..3ca39c4e5d2a 100644
--- a/fs/xfs/linux-2.6/xfs_linux.h
+++ b/fs/xfs/linux-2.6/xfs_linux.h
@@ -138,43 +138,17 @@
 
 #define spinlock_destroy(lock)
 
-#define NBPP            PAGE_SIZE
-#define NDPP            (1 << (PAGE_SHIFT - 9))
-
 #define NBBY            8               /* number of bits per byte */
-#define NBPC            PAGE_SIZE       /* Number of bytes per click */
-#define BPCSHIFT        PAGE_SHIFT      /* LOG2(NBPC) if exact */
 
 /*
  * Size of block device i/o is parameterized here.
  * Currently the system supports page-sized i/o.
  */
-#define BLKDEV_IOSHIFT          BPCSHIFT
+#define BLKDEV_IOSHIFT          PAGE_CACHE_SHIFT
 #define BLKDEV_IOSIZE           (1<<BLKDEV_IOSHIFT)
 /* number of BB's per block device block */
 #define BLKDEV_BB               BTOBB(BLKDEV_IOSIZE)
 
-/* bytes to clicks */
-#define btoc(x)         (((__psunsigned_t)(x)+(NBPC-1))>>BPCSHIFT)
-#define btoct(x)        ((__psunsigned_t)(x)>>BPCSHIFT)
-#define btoc64(x)       (((__uint64_t)(x)+(NBPC-1))>>BPCSHIFT)
-#define btoct64(x)      ((__uint64_t)(x)>>BPCSHIFT)
-
-/* off_t bytes to clicks */
-#define offtoc(x)       (((__uint64_t)(x)+(NBPC-1))>>BPCSHIFT)
-#define offtoct(x)      ((xfs_off_t)(x)>>BPCSHIFT)
-
-/* clicks to off_t bytes */
-#define ctooff(x)       ((xfs_off_t)(x)<<BPCSHIFT)
-
-/* clicks to bytes */
-#define ctob(x)         ((__psunsigned_t)(x)<<BPCSHIFT)
-#define btoct(x)        ((__psunsigned_t)(x)>>BPCSHIFT)
-#define ctob64(x)       ((__uint64_t)(x)<<BPCSHIFT)
-
-/* bytes to clicks */
-#define btoc(x)         (((__psunsigned_t)(x)+(NBPC-1))>>BPCSHIFT)
-
 #define ENOATTR         ENODATA         /* Attribute not found */
 #define EWRONGFS        EINVAL          /* Mount with wrong filesystem type */
 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 19a1f077dbd6..6c3a846a5267 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -243,9 +243,8 @@ xfs_read(
 
         if (unlikely(ioflags & IO_ISDIRECT)) {
                 if (VN_CACHED(vp))
-                        ret = xfs_flushinval_pages(ip,
-                                        ctooff(offtoct(*offset)),
-                                        -1, FI_REMAPF_LOCKED);
+                        ret = xfs_flushinval_pages(ip, (*offset & PAGE_CACHE_MASK),
+                                                    -1, FI_REMAPF_LOCKED);
                 mutex_unlock(&inode->i_mutex);
                 if (ret) {
                         xfs_iunlock(ip, XFS_IOLOCK_SHARED);
@@ -731,9 +730,9 @@ retry:
                 if (VN_CACHED(vp)) {
                         WARN_ON(need_i_mutex == 0);
                         xfs_inval_cached_trace(xip, pos, -1,
-                                        ctooff(offtoct(pos)), -1);
+                                        (pos & PAGE_CACHE_MASK), -1);
                         error = xfs_flushinval_pages(xip,
-                                        ctooff(offtoct(pos)),
+                                        (pos & PAGE_CACHE_MASK),
                                         -1, FI_REMAPF_LOCKED);
                         if (error)
                                 goto out_unlock_internal;