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
ffs_fragacct_swap(struct fs * fs,int fragmap,uint32_t fraglist[],int cnt,int needswap)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
ffs_isblock(struct fs * fs,u_char * cp,int32_t h)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
ffs_isfreeblock(struct fs * fs,u_char * cp,int32_t h)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
ffs_clrblock(struct fs * fs,u_char * cp,int32_t h)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
ffs_setblock(struct fs * fs,u_char * cp,int32_t h)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