[PATCH] remove BPCSHIFT and NB?P? macros - was fs/xfs: remove duplicated

[Timothy Shimmin <tes@sgi.com>]

David Chinner wrote:
>> While here, looking at a few others...
>> #define NBPP            PAGE_SIZE
>> #define NDPP            (1 << (PAGE_SHIFT - 9)) <--- not used - another to nuke
>> #define NBPC            PAGE_SIZE <----- used once
>>
>> grep -Ir 'NBPC' . | egrep -v 'tag|anot|diff'
>> ./linux-2.6/xfs_linux.h:#define NBPC            PAGE_SIZE       /* Number of bytes per click */
>> ./xfs_itable.c: irbuf = kmem_zalloc_greedy(&irbsize, NBPC, NBPC * 4,
>>
>>  > grep -Ir 'NBPP' . | egrep -v 'tag|anot|diff|NBPPR'
>> ./linux-2.6/xfs_linux.h:#define NBPP            PAGE_SIZE
>> ./quota/xfs_qm.h:#define XFS_QM_HASHSIZE_LOW            (NBPP / sizeof(xfs_dqhash_t))
>> ./quota/xfs_qm.h:#define XFS_QM_HASHSIZE_HIGH           ((NBPP * 4) / sizeof(xfs_dqhash_t))
> 
> PAGE_SIZE
> 
>> ./xfs_bmap.c:   } else if (mp->m_sb.sb_blocksize >= NBPP) {
>> ./xfs_bmap.c:           args.prod = NBPP >> mp->m_sb.sb_blocklog;
> 
> PAGE_CACHE_SIZE
> 
>> ./xfs_itable.c: bcount = MIN(left, (int)(NBPP / sizeof(*buffer)));
> 
> PAGE_SIZE
> 
>> ./xfs_log.c:                    kmem_free(tic, NBPP);
>> ./xfs_log.c:    uint            i = (NBPP / sizeof(xlog_ticket_t)) - 2;
>> ./xfs_log.c:    buf = (xfs_caddr_t) kmem_zalloc(NBPP, KM_SLEEP);
> 
> We should replace that hand rolled ticket allocator with a slab cache.
> 
In another patch though.

>> ./xfs_vnodeops.c:       rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, NBPP);
> 
> PAGE_CACHE_SIZE. (as suggested ;)
> 
>> Might as well get rid of NBPC and replace by NBPP.
>>
>> Is it just worth s/NBPC/PAGE_SIZE/g ?
> 
> yup.
> 
Thanks.

Patch:
-------------

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.

Signed-Off-By: Tim Shimmin <tes@sgi.com>
---
  b/fs/xfs/linux-2.6/xfs_linux.h |   28 +---------------------------
  b/fs/xfs/linux-2.6/xfs_lrw.c   |    9 ++++-----
  b/fs/xfs/quota/xfs_qm.h        |    4 ++--
  b/fs/xfs/xfs_bmap.c            |    4 ++--
  b/fs/xfs/xfs_itable.c          |    4 ++--
  b/fs/xfs/xfs_log.c             |    6 +++---
  b/fs/xfs/xfs_vnodeops.c        |    9 +++------
  7 files changed, 17 insertions(+), 47 deletions(-)

=====================================Index: fs/xfs/linux-2.6/xfs_linux.h
=====================================
--- a/fs/xfs/linux-2.6/xfs_linux.h	2007-11-16 16:22:40.000000000 +1100
+++ b/fs/xfs/linux-2.6/xfs_linux.h	2007-11-16 15:59:22.299466117 +1100
@@ -143,43 +143,17 @@

  #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 */

=====================================Index: fs/xfs/linux-2.6/xfs_lrw.c
=====================================
--- a/fs/xfs/linux-2.6/xfs_lrw.c	2007-11-16 16:22:40.000000000 +1100
+++ b/fs/xfs/linux-2.6/xfs_lrw.c	2007-11-15 11:32:12.451249159 +1100
@@ -254,9 +254,8 @@ 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);
@@ -742,9 +741,9 @@ 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;

=====================================Index: fs/xfs/quota/xfs_qm.h
=====================================
--- a/fs/xfs/quota/xfs_qm.h	2007-11-16 16:22:40.000000000 +1100
+++ b/fs/xfs/quota/xfs_qm.h	2007-11-16 15:39:53.373375739 +1100
@@ -52,8 +52,8 @@ extern kmem_zone_t	*qm_dqtrxzone;
  /*
   * 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.

=====================================Index: fs/xfs/xfs_bmap.c
=====================================
--- a/fs/xfs/xfs_bmap.c	2007-11-16 16:22:41.000000000 +1100
+++ b/fs/xfs/xfs_bmap.c	2007-11-16 15:40:27.017050666 +1100
@@ -2830,11 +2830,11 @@ xfs_bmap_btalloc(
  		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);
  	}

=====================================Index: fs/xfs/xfs_itable.c
=====================================
--- a/fs/xfs/xfs_itable.c	2007-11-16 16:22:40.000000000 +1100
+++ b/fs/xfs/xfs_itable.c	2007-11-16 16:05:51.381600461 +1100
@@ -393,7 +393,7 @@ xfs_bulkstat(
  		(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);

@@ -815,7 +815,7 @@ xfs_inumbers(
  	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;

=====================================Index: fs/xfs/xfs_log.c
=====================================
--- a/fs/xfs/xfs_log.c	2007-11-16 16:22:40.000000000 +1100
+++ b/fs/xfs/xfs_log.c	2007-11-16 15:56:42.615917720 +1100
@@ -1552,7 +1552,7 @@ xlog_dealloc_log(xlog_t *log)
  		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_state_ticket_alloc(xlog_t *log)
  	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);


=====================================Index: fs/xfs/xfs_vnodeops.c
=====================================
--- a/fs/xfs/xfs_vnodeops.c	2007-11-16 16:22:41.000000000 +1100
+++ b/fs/xfs/xfs_vnodeops.c	2007-11-16 15:57:01.449505791 +1100
@@ -4164,15 +4164,12 @@ xfs_free_file_space(
  		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;
  	}