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 #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, int32_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(fs, cp, h) 87 struct fs *fs; 88 u_char *cp; 89 int32_t h; 90 { 91 u_char mask; 92 93 switch ((int)fs->fs_fragshift) { 94 case 3: 95 return (cp[h] == 0xff); 96 case 2: 97 mask = 0x0f << ((h & 0x1) << 2); 98 return ((cp[h >> 1] & mask) == mask); 99 case 1: 100 mask = 0x03 << ((h & 0x3) << 1); 101 return ((cp[h >> 2] & mask) == mask); 102 case 0: 103 mask = 0x01 << (h & 0x7); 104 return ((cp[h >> 3] & mask) == mask); 105 default: 106 panic("ffs_isblock: unknown fs_fragshift %d", 107 (int)fs->fs_fragshift); 108 } 109 } 110 111 /* 112 * check if a block is completely allocated 113 * returns true if all the corresponding bits in the free map are 0 114 * returns false if any corresponding bit in the free map is 1 115 */ 116 int 117 ffs_isfreeblock(fs, cp, h) 118 struct fs *fs; 119 u_char *cp; 120 int32_t h; 121 { 122 123 switch ((int)fs->fs_fragshift) { 124 case 3: 125 return (cp[h] == 0); 126 case 2: 127 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 128 case 1: 129 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 130 case 0: 131 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 132 default: 133 panic("ffs_isfreeblock: unknown fs_fragshift %d", 134 (int)fs->fs_fragshift); 135 } 136 } 137 138 /* 139 * take a block out of the map 140 */ 141 void 142 ffs_clrblock(fs, cp, h) 143 struct fs *fs; 144 u_char *cp; 145 int32_t h; 146 { 147 148 switch ((int)fs->fs_fragshift) { 149 case 3: 150 cp[h] = 0; 151 return; 152 case 2: 153 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 154 return; 155 case 1: 156 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 157 return; 158 case 0: 159 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 160 return; 161 default: 162 panic("ffs_clrblock: unknown fs_fragshift %d", 163 (int)fs->fs_fragshift); 164 } 165 } 166 167 /* 168 * put a block into the map 169 */ 170 void 171 ffs_setblock(fs, cp, h) 172 struct fs *fs; 173 u_char *cp; 174 int32_t h; 175 { 176 177 switch ((int)fs->fs_fragshift) { 178 case 3: 179 cp[h] = 0xff; 180 return; 181 case 2: 182 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 183 return; 184 case 1: 185 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 186 return; 187 case 0: 188 cp[h >> 3] |= (0x01 << (h & 0x7)); 189 return; 190 default: 191 panic("ffs_setblock: unknown fs_fragshift %d", 192 (int)fs->fs_fragshift); 193 } 194 } 195