/*
- * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of version 2 of the GNU General Public License as
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
- * This program is distributed in the hope that it would be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
*
- * Further, this software is distributed without any warranty that it is
- * free of the rightful claim of any third person regarding infringement
- * or the like. Any license provided herein, whether implied or
- * otherwise, applies only to this software file. Patent licenses, if
- * any, provided herein do not apply to combinations of this program with
- * other software, or any other product whatsoever.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write the Free Software Foundation, Inc., 59
- * Temple Place - Suite 330, Boston MA 02111-1307, USA.
- *
- * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
- * Mountain View, CA 94043, or:
- *
- * http://www.sgi.com
- *
- * For further information regarding this notice, see:
- *
- * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
- */
-
-/*
- * XFS bit manipulation routines, used in non-realtime code.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
-
#include "xfs.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
+/*
+ * XFS bit manipulation routines, used in non-realtime code.
+ */
#ifndef HAVE_ARCH_HIGHBIT
/*
* Index of high bit number in byte, -1 for none set, 0..7 otherwise.
*/
-STATIC const char xfs_highbit[256] = {
+static const char xfs_highbit[256] = {
-1, 0, 1, 1, 2, 2, 2, 2, /* 00 .. 07 */
3, 3, 3, 3, 3, 3, 3, 3, /* 08 .. 0f */
4, 4, 4, 4, 4, 4, 4, 4, /* 10 .. 17 */
};
#endif
-/*
- * Count of bits set in byte, 0..8.
- */
-static const char xfs_countbit[256] = {
- 0, 1, 1, 2, 1, 2, 2, 3, /* 00 .. 07 */
- 1, 2, 2, 3, 2, 3, 3, 4, /* 08 .. 0f */
- 1, 2, 2, 3, 2, 3, 3, 4, /* 10 .. 17 */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 18 .. 1f */
- 1, 2, 2, 3, 2, 3, 3, 4, /* 20 .. 27 */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 28 .. 2f */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 30 .. 37 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* 38 .. 3f */
- 1, 2, 2, 3, 2, 3, 3, 4, /* 40 .. 47 */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 48 .. 4f */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 50 .. 57 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* 58 .. 5f */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 60 .. 67 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* 68 .. 6f */
- 3, 4, 4, 5, 4, 5, 5, 6, /* 70 .. 77 */
- 4, 5, 5, 6, 5, 6, 6, 7, /* 78 .. 7f */
- 1, 2, 2, 3, 2, 3, 3, 4, /* 80 .. 87 */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 88 .. 8f */
- 2, 3, 3, 4, 3, 4, 4, 5, /* 90 .. 97 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* 98 .. 9f */
- 2, 3, 3, 4, 3, 4, 4, 5, /* a0 .. a7 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* a8 .. af */
- 3, 4, 4, 5, 4, 5, 5, 6, /* b0 .. b7 */
- 4, 5, 5, 6, 5, 6, 6, 7, /* b8 .. bf */
- 2, 3, 3, 4, 3, 4, 4, 5, /* c0 .. c7 */
- 3, 4, 4, 5, 4, 5, 5, 6, /* c8 .. cf */
- 3, 4, 4, 5, 4, 5, 5, 6, /* d0 .. d7 */
- 4, 5, 5, 6, 5, 6, 6, 7, /* d8 .. df */
- 3, 4, 4, 5, 4, 5, 5, 6, /* e0 .. e7 */
- 4, 5, 5, 6, 5, 6, 6, 7, /* e8 .. ef */
- 4, 5, 5, 6, 5, 6, 6, 7, /* f0 .. f7 */
- 5, 6, 6, 7, 6, 7, 7, 8, /* f8 .. ff */
-};
-
/*
* xfs_highbit32: get high bit set out of 32-bit argument, -1 if none set.
*/
/*
- * Count the number of bits set in the bitmap starting with bit
- * start_bit. Size is the size of the bitmap in words.
- *
- * Do the counting by mapping a byte value to the number of set
- * bits for that value using the xfs_countbit array, i.e.
- * xfs_countbit[0] == 0, xfs_countbit[1] == 1, xfs_countbit[2] == 1,
- * xfs_countbit[3] == 2, etc.
+ * Return whether bitmap is empty.
+ * Size is number of words in the bitmap, which is padded to word boundary
+ * Returns 1 for empty, 0 for non-empty.
*/
int
-xfs_count_bits(uint *map, uint size, uint start_bit)
+xfs_bitmap_empty(uint *map, uint size)
{
- register int bits;
- register unsigned char *bytep;
- register unsigned char *end_map;
- int byte_bit;
-
- bits = 0;
- end_map = (char*)(map + size);
- bytep = (char*)(map + (start_bit & ~0x7));
- byte_bit = start_bit & 0x7;
-
- /*
- * If the caller fell off the end of the map, return 0.
- */
- if (bytep >= end_map) {
- return (0);
- }
-
- /*
- * If start_bit is not byte aligned, then process the
- * first byte separately.
- */
- if (byte_bit != 0) {
- /*
- * Shift off the bits we don't want to look at,
- * before indexing into xfs_countbit.
- */
- bits += xfs_countbit[(*bytep >> byte_bit)];
- bytep++;
- }
+ uint i;
+ uint ret = 0;
- /*
- * Count the bits in each byte until the end of the bitmap.
- */
- while (bytep < end_map) {
- bits += xfs_countbit[*bytep];
- bytep++;
+ for (i = 0; i < size; i++) {
+ ret |= map[i];
}
- return (bits);
+ return (ret == 0);
}
/*
projects / linux-2.6-omap-h63xx.git / blobdiff