[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>
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index d9ca3c0..a451baa 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -399,7 +399,7 @@
 		(XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog);
 	nimask = ~(nicluster - 1);
 	nbcluster = nicluster >> mp->m_sb.sb_inopblog;
-	irbuf = kmem_zalloc_greedy(&irbsize, NBPC, NBPC * 4,
+	irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4,
 				   KM_SLEEP | KM_MAYFAIL | KM_LARGE);
 	nirbuf = irbsize / sizeof(*irbuf);
 
@@ -830,7 +830,7 @@
 	agino = XFS_INO_TO_AGINO(mp, ino);
 	left = *count;
 	*count = 0;
-	bcount = MIN(left, (int)(NBPP / sizeof(*buffer)));
+	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
 	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
 	error = bufidx = 0;
 	cur = NULL;