1 /* $NetBSD: ffs_subr.c,v 1.32 2003/12/30 12:33:24 pk Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 1982, 1986, 1989, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ffs_subr.c 8.5 (Berkeley) 3/21/95 34 */ 35 36 #include <sys/cdefs.h> 37 #include <sys/param.h> 38 #include <sys/types.h> 39 40 #include <ufs/ufs/dinode.h> 41 #include <ufs/ffs/fs.h> 42 #include "ffs/ffs_extern.h" 43 #include "ffs/ufs_bswap.h" 44 45 /* 46 * Update the frsum fields to reflect addition or deletion 47 * of some frags. 48 */ 49 void 50 ffs_fragacct_swap(struct fs *fs, int fragmap, uint32_t fraglist[], int cnt, int needswap) 51 { 52 int inblk; 53 int field, subfield; 54 int siz, pos; 55 56 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 57 fragmap <<= 1; 58 for (siz = 1; siz < fs->fs_frag; siz++) { 59 if ((inblk & (1 << (siz + (fs->fs_frag & (NBBY - 1))))) == 0) 60 continue; 61 field = around[siz]; 62 subfield = inside[siz]; 63 for (pos = siz; pos <= fs->fs_frag; pos++) { 64 if ((fragmap & field) == subfield) { 65 fraglist[siz] = ufs_rw32( 66 ufs_rw32(fraglist[siz], needswap) + cnt, 67 needswap); 68 pos += siz; 69 field <<= siz; 70 subfield <<= siz; 71 } 72 field <<= 1; 73 subfield <<= 1; 74 } 75 } 76 } 77 78 /* 79 * block operations 80 * 81 * check if a block is available 82 * returns true if all the corresponding bits in the free map are 1 83 * returns false if any corresponding bit in the free map is 0 84 */ 85 int 86 ffs_isblock(struct fs *fs, u_char *cp, int32_t h) 87 { 88 u_char mask; 89 90 switch ((int)fs->fs_fragshift) { 91 case 3: 92 return (cp[h] == 0xff); 93 case 2: 94 mask = 0x0f << ((h & 0x1) << 2); 95 return ((cp[h >> 1] & mask) == mask); 96 case 1: 97 mask = 0x03 << ((h & 0x3) << 1); 98 return ((cp[h >> 2] & mask) == mask); 99 case 0: 100 mask = 0x01 << (h & 0x7); 101 return ((cp[h >> 3] & mask) == mask); 102 default: 103 panic("ffs_isblock: unknown fs_fragshift %d", 104 (int)fs->fs_fragshift); 105 } 106 } 107 108 /* 109 * check if a block is completely allocated 110 * returns true if all the corresponding bits in the free map are 0 111 * returns false if any corresponding bit in the free map is 1 112 */ 113 int 114 ffs_isfreeblock(struct fs *fs, u_char *cp, int32_t h) 115 { 116 117 switch ((int)fs->fs_fragshift) { 118 case 3: 119 return (cp[h] == 0); 120 case 2: 121 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 122 case 1: 123 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 124 case 0: 125 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 126 default: 127 panic("ffs_isfreeblock: unknown fs_fragshift %d", 128 (int)fs->fs_fragshift); 129 } 130 } 131 132 /* 133 * take a block out of the map 134 */ 135 void 136 ffs_clrblock(struct fs *fs, u_char *cp, int32_t h) 137 { 138 139 switch ((int)fs->fs_fragshift) { 140 case 3: 141 cp[h] = 0; 142 return; 143 case 2: 144 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 145 return; 146 case 1: 147 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 148 return; 149 case 0: 150 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 151 return; 152 default: 153 panic("ffs_clrblock: unknown fs_fragshift %d", 154 (int)fs->fs_fragshift); 155 } 156 } 157 158 /* 159 * put a block into the map 160 */ 161 void 162 ffs_setblock(struct fs *fs, u_char *cp, int32_t h) 163 { 164 165 switch ((int)fs->fs_fragshift) { 166 case 3: 167 cp[h] = 0xff; 168 return; 169 case 2: 170 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 171 return; 172 case 1: 173 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 174 return; 175 case 0: 176 cp[h >> 3] |= (0x01 << (h & 0x7)); 177 return; 178 default: 179 panic("ffs_setblock: unknown fs_fragshift %d", 180 (int)fs->fs_fragshift); 181 } 182 } 183