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 34 #include <sys/param.h> 35 #include <sys/types.h> 36 37 #include <ufs/ufs/dinode.h> 38 #include <ufs/ffs/fs.h> 39 #include "ffs/ffs_extern.h" 40 #include "ffs/ufs_bswap.h" 41 42 /* 43 * Update the frsum fields to reflect addition or deletion 44 * of some frags. 45 */ 46 void 47 ffs_fragacct_swap(struct fs *fs, int fragmap, uint32_t fraglist[], int cnt, int needswap) 48 { 49 int inblk; 50 int field, subfield; 51 int siz, pos; 52 53 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 54 fragmap <<= 1; 55 for (siz = 1; siz < fs->fs_frag; siz++) { 56 if ((inblk & (1 << (siz + (fs->fs_frag & (NBBY - 1))))) == 0) 57 continue; 58 field = around[siz]; 59 subfield = inside[siz]; 60 for (pos = siz; pos <= fs->fs_frag; pos++) { 61 if ((fragmap & field) == subfield) { 62 fraglist[siz] = ufs_rw32( 63 ufs_rw32(fraglist[siz], needswap) + cnt, 64 needswap); 65 pos += siz; 66 field <<= siz; 67 subfield <<= siz; 68 } 69 field <<= 1; 70 subfield <<= 1; 71 } 72 } 73 } 74 75 /* 76 * block operations 77 * 78 * check if a block is available 79 * returns true if all the corresponding bits in the free map are 1 80 * returns false if any corresponding bit in the free map is 0 81 */ 82 int 83 ffs_isblock(struct fs *fs, u_char *cp, int32_t h) 84 { 85 u_char mask; 86 87 switch ((int)fs->fs_fragshift) { 88 case 3: 89 return (cp[h] == 0xff); 90 case 2: 91 mask = 0x0f << ((h & 0x1) << 2); 92 return ((cp[h >> 1] & mask) == mask); 93 case 1: 94 mask = 0x03 << ((h & 0x3) << 1); 95 return ((cp[h >> 2] & mask) == mask); 96 case 0: 97 mask = 0x01 << (h & 0x7); 98 return ((cp[h >> 3] & mask) == mask); 99 default: 100 panic("ffs_isblock: unknown fs_fragshift %d", 101 (int)fs->fs_fragshift); 102 } 103 } 104 105 /* 106 * check if a block is completely allocated 107 * returns true if all the corresponding bits in the free map are 0 108 * returns false if any corresponding bit in the free map is 1 109 */ 110 int 111 ffs_isfreeblock(struct fs *fs, u_char *cp, int32_t h) 112 { 113 114 switch ((int)fs->fs_fragshift) { 115 case 3: 116 return (cp[h] == 0); 117 case 2: 118 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 119 case 1: 120 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 121 case 0: 122 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 123 default: 124 panic("ffs_isfreeblock: unknown fs_fragshift %d", 125 (int)fs->fs_fragshift); 126 } 127 } 128 129 /* 130 * take a block out of the map 131 */ 132 void 133 ffs_clrblock(struct fs *fs, u_char *cp, int32_t h) 134 { 135 136 switch ((int)fs->fs_fragshift) { 137 case 3: 138 cp[h] = 0; 139 return; 140 case 2: 141 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 142 return; 143 case 1: 144 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 145 return; 146 case 0: 147 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 148 return; 149 default: 150 panic("ffs_clrblock: unknown fs_fragshift %d", 151 (int)fs->fs_fragshift); 152 } 153 } 154 155 /* 156 * put a block into the map 157 */ 158 void 159 ffs_setblock(struct fs *fs, u_char *cp, int32_t h) 160 { 161 162 switch ((int)fs->fs_fragshift) { 163 case 3: 164 cp[h] = 0xff; 165 return; 166 case 2: 167 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 168 return; 169 case 1: 170 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 171 return; 172 case 0: 173 cp[h >> 3] |= (0x01 << (h & 0x7)); 174 return; 175 default: 176 panic("ffs_setblock: unknown fs_fragshift %d", 177 (int)fs->fs_fragshift); 178 } 179 } 180