[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_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index 5322d9f..7f380e8 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -4164,15 +4164,12 @@
 		vn_iowait(ip);	/* wait for the completion of any pending DIOs */
 	}
 
-	rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, NBPP);
+	rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
 	ioffset = offset & ~(rounding - 1);
 
 	if (VN_CACHED(vp) != 0) {
-		xfs_inval_cached_trace(ip, ioffset, -1,
-				ctooff(offtoct(ioffset)), -1);
-		error = xfs_flushinval_pages(ip,
-				ctooff(offtoct(ioffset)),
-				-1, FI_REMAPF_LOCKED);
+		xfs_inval_cached_trace(ip, ioffset, -1, ioffset, -1);
+		error = xfs_flushinval_pages(ip, ioffset, -1, FI_REMAPF_LOCKED);
 		if (error)
 			goto out_unlock_iolock;
 	}