1 /* $NetBSD: ffs_subr.c,v 1.32 2003/12/30 12:33:24 pk Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)ffs_subr.c 8.5 (Berkeley) 3/21/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 39 #include <ufs/ufs/dinode.h> 40 #include <ufs/ffs/fs.h> 41 #include "ffs/ffs_extern.h" 42 #include "ffs/ufs_bswap.h" 43 44 /* 45 * Update the frsum fields to reflect addition or deletion 46 * of some frags. 47 */ 48 void 49 ffs_fragacct_swap(struct fs *fs, int fragmap, int32_t fraglist[], int cnt, int needswap) 50 { 51 int inblk; 52 int field, subfield; 53 int siz, pos; 54 55 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 56 fragmap <<= 1; 57 for (siz = 1; siz < fs->fs_frag; siz++) { 58 if ((inblk & (1 << (siz + (fs->fs_frag & (NBBY - 1))))) == 0) 59 continue; 60 field = around[siz]; 61 subfield = inside[siz]; 62 for (pos = siz; pos <= fs->fs_frag; pos++) { 63 if ((fragmap & field) == subfield) { 64 fraglist[siz] = ufs_rw32( 65 ufs_rw32(fraglist[siz], needswap) + cnt, 66 needswap); 67 pos += siz; 68 field <<= siz; 69 subfield <<= siz; 70 } 71 field <<= 1; 72 subfield <<= 1; 73 } 74 } 75 } 76 77 /* 78 * block operations 79 * 80 * check if a block is available 81 * returns true if all the corresponding bits in the free map are 1 82 * returns false if any corresponding bit in the free map is 0 83 */ 84 int 85 ffs_isblock(fs, cp, h) 86 struct fs *fs; 87 u_char *cp; 88 int32_t h; 89 { 90 u_char mask; 91 92 switch ((int)fs->fs_fragshift) { 93 case 3: 94 return (cp[h] == 0xff); 95 case 2: 96 mask = 0x0f << ((h & 0x1) << 2); 97 return ((cp[h >> 1] & mask) == mask); 98 case 1: 99 mask = 0x03 << ((h & 0x3) << 1); 100 return ((cp[h >> 2] & mask) == mask); 101 case 0: 102 mask = 0x01 << (h & 0x7); 103 return ((cp[h >> 3] & mask) == mask); 104 default: 105 panic("ffs_isblock: unknown fs_fragshift %d", 106 (int)fs->fs_fragshift); 107 } 108 } 109 110 /* 111 * check if a block is completely allocated 112 * returns true if all the corresponding bits in the free map are 0 113 * returns false if any corresponding bit in the free map is 1 114 */ 115 int 116 ffs_isfreeblock(fs, cp, h) 117 struct fs *fs; 118 u_char *cp; 119 int32_t h; 120 { 121 122 switch ((int)fs->fs_fragshift) { 123 case 3: 124 return (cp[h] == 0); 125 case 2: 126 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 127 case 1: 128 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 129 case 0: 130 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 131 default: 132 panic("ffs_isfreeblock: unknown fs_fragshift %d", 133 (int)fs->fs_fragshift); 134 } 135 } 136 137 /* 138 * take a block out of the map 139 */ 140 void 141 ffs_clrblock(fs, cp, h) 142 struct fs *fs; 143 u_char *cp; 144 int32_t h; 145 { 146 147 switch ((int)fs->fs_fragshift) { 148 case 3: 149 cp[h] = 0; 150 return; 151 case 2: 152 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 153 return; 154 case 1: 155 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 156 return; 157 case 0: 158 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 159 return; 160 default: 161 panic("ffs_clrblock: unknown fs_fragshift %d", 162 (int)fs->fs_fragshift); 163 } 164 } 165 166 /* 167 * put a block into the map 168 */ 169 void 170 ffs_setblock(fs, cp, h) 171 struct fs *fs; 172 u_char *cp; 173 int32_t h; 174 { 175 176 switch ((int)fs->fs_fragshift) { 177 case 3: 178 cp[h] = 0xff; 179 return; 180 case 2: 181 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 182 return; 183 case 1: 184 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 185 return; 186 case 0: 187 cp[h >> 3] |= (0x01 << (h & 0x7)); 188 return; 189 default: 190 panic("ffs_setblock: unknown fs_fragshift %d", 191 (int)fs->fs_fragshift); 192 } 193 } 194