NetBSD/sys/ufs/ffs/ffs_tables.c

144 lines
5.8 KiB
C

/* $NetBSD: ffs_tables.c,v 1.6 2003/08/07 16:34:31 agc Exp $ */
/*
* Copyright (c) 1982, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ffs_tables.c 8.1 (Berkeley) 6/11/93
*/
#include <sys/cdefs.h>
#if defined(__KERNEL_RCSID)
__KERNEL_RCSID(0, "$NetBSD: ffs_tables.c,v 1.6 2003/08/07 16:34:31 agc Exp $");
#endif
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/param.h>
/*
* Bit patterns for identifying fragments in the block map
* used as ((map & around) == inside)
*/
const int around[9] = {
0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
};
const int inside[9] = {
0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
};
/*
* Given a block map bit pattern, the frag tables tell whether a
* particular size fragment is available.
*
* used as:
* if ((1 << (size - 1)) & fragtbl[fs->fs_frag][map] {
* at least one fragment of the indicated size is available
* }
*
* These tables are used by the scanc instruction on the VAX to
* quickly find an appropriate fragment.
*/
const u_char fragtbl124[256] = {
0x00, 0x16, 0x16, 0x2a, 0x16, 0x16, 0x26, 0x4e,
0x16, 0x16, 0x16, 0x3e, 0x2a, 0x3e, 0x4e, 0x8a,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x26, 0x36, 0x36, 0x2e, 0x36, 0x36, 0x26, 0x6e,
0x36, 0x36, 0x36, 0x3e, 0x2e, 0x3e, 0x6e, 0xae,
0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
0x8a, 0x9e, 0x9e, 0xaa, 0x9e, 0x9e, 0xae, 0xce,
0x9e, 0x9e, 0x9e, 0xbe, 0xaa, 0xbe, 0xce, 0x8a,
};
const u_char fragtbl8[256] = {
0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04,
0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
0x08, 0x09, 0x09, 0x0a, 0x10, 0x11, 0x20, 0x40,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0a, 0x12,
0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0c,
0x08, 0x09, 0x09, 0x0a, 0x09, 0x09, 0x0a, 0x0c,
0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
};
/*
* The actual fragtbl array.
*/
const u_char * const fragtbl[MAXFRAG + 1] = {
0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8,
};