[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/linux-2.6/xfs_linux.h b/fs/xfs/linux-2.6/xfs_linux.h
index 9bf4f7e..3ca39c4 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 19a1f07..6c3a846 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -243,9 +243,8 @@
 
 	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 @@
 		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;
diff --git a/fs/xfs/quota/xfs_qm.h b/fs/xfs/quota/xfs_qm.h
index 023400a..baf537c 100644
--- a/fs/xfs/quota/xfs_qm.h
+++ b/fs/xfs/quota/xfs_qm.h
@@ -52,8 +52,8 @@
 /*
  * Dquot hashtable constants/threshold values.
  */
-#define XFS_QM_HASHSIZE_LOW		(NBPP / sizeof(xfs_dqhash_t))
-#define XFS_QM_HASHSIZE_HIGH		((NBPP * 4) / sizeof(xfs_dqhash_t))
+#define XFS_QM_HASHSIZE_LOW		(PAGE_SIZE / sizeof(xfs_dqhash_t))
+#define XFS_QM_HASHSIZE_HIGH		((PAGE_SIZE * 4) / sizeof(xfs_dqhash_t))
 
 /*
  * This defines the unit of allocation of dquots.
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index aca51e7..1c0a5a5 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -2830,11 +2830,11 @@
 		args.prod = align;
 		if ((args.mod = (xfs_extlen_t)do_mod(ap->off, args.prod)))
 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
-	} else if (mp->m_sb.sb_blocksize >= NBPP) {
+	} else if (mp->m_sb.sb_blocksize >= PAGE_CACHE_SIZE) {
 		args.prod = 1;
 		args.mod = 0;
 	} else {
-		args.prod = NBPP >> mp->m_sb.sb_blocklog;
+		args.prod = PAGE_CACHE_SIZE >> mp->m_sb.sb_blocklog;
 		if ((args.mod = (xfs_extlen_t)(do_mod(ap->off, args.prod))))
 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
 	}
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;
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 7ed15bd..4c86a26 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -1552,7 +1552,7 @@
 		tic = log->l_unmount_free;
 		while (tic) {
 			next_tic = tic->t_next;
-			kmem_free(tic, NBPP);
+			kmem_free(tic, PAGE_SIZE);
 			tic = next_tic;
 		}
 	}
@@ -3161,13 +3161,13 @@
 	xlog_ticket_t	*t_list;
 	xlog_ticket_t	*next;
 	xfs_caddr_t	buf;
-	uint		i = (NBPP / sizeof(xlog_ticket_t)) - 2;
+	uint		i = (PAGE_SIZE / sizeof(xlog_ticket_t)) - 2;
 
 	/*
 	 * The kmem_zalloc may sleep, so we shouldn't be holding the
 	 * global lock.  XXXmiken: may want to use zone allocator.
 	 */
-	buf = (xfs_caddr_t) kmem_zalloc(NBPP, KM_SLEEP);
+	buf = (xfs_caddr_t) kmem_zalloc(PAGE_SIZE, KM_SLEEP);
 
 	spin_lock(&log->l_icloglock);
 
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;
 	}