xref: /386bsd/usr/src/kernel/ufs/ufs_subr.c (revision dc8b130e)
1 /*
2  * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. 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  *	$Id: ufs_subr.c,v 1.1 94/10/20 10:56:44 root Exp $
34  */
35 
36 #include <sys/param.h>
37 
38 #include "ufs.h"
39 #ifdef KERNEL
40 #include "sys/errno.h"
41 #include "prototypes.h"
42 #endif
43 
44 
45 extern	int around[9];
46 extern	int inside[9];
47 extern	u_char *fragtbl[];
48 
49 /*
50  * Update the frsum fields to reflect addition or deletion
51  * of some frags.
52  */
53 fragacct(fs, fragmap, fraglist, cnt)
54 	struct fs *fs;
55 	int fragmap;
56 	long fraglist[];
57 	int cnt;
58 {
59 	int inblk;
60 	register int field, subfield;
61 	register int siz, pos;
62 
63 	inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
64 	fragmap <<= 1;
65 	for (siz = 1; siz < fs->fs_frag; siz++) {
66 		if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
67 			continue;
68 		field = around[siz];
69 		subfield = inside[siz];
70 		for (pos = siz; pos <= fs->fs_frag; pos++) {
71 			if ((fragmap & field) == subfield) {
72 				fraglist[siz] += cnt;
73 				pos += siz;
74 				field <<= siz;
75 				subfield <<= siz;
76 			}
77 			field <<= 1;
78 			subfield <<= 1;
79 		}
80 	}
81 }
82 
83 /*
84  * block operations
85  *
86  * check if a block is available
87  */
88 isblock(fs, cp, h)
89 	struct fs *fs;
90 	unsigned char *cp;
91 	daddr_t h;
92 {
93 	unsigned char mask;
94 
95 	switch ((int)fs->fs_frag) {
96 	case 8:
97 		return (cp[h] == 0xff);
98 	case 4:
99 		mask = 0x0f << ((h & 0x1) << 2);
100 		return ((cp[h >> 1] & mask) == mask);
101 	case 2:
102 		mask = 0x03 << ((h & 0x3) << 1);
103 		return ((cp[h >> 2] & mask) == mask);
104 	case 1:
105 		mask = 0x01 << (h & 0x7);
106 		return ((cp[h >> 3] & mask) == mask);
107 	default:
108 		panic("isblock");
109 		return (NULL);
110 	}
111 }
112 
113 /*
114  * take a block out of the map
115  */
116 clrblock(fs, cp, h)
117 	struct fs *fs;
118 	u_char *cp;
119 	daddr_t h;
120 {
121 
122 	switch ((int)fs->fs_frag) {
123 	case 8:
124 		cp[h] = 0;
125 		return;
126 	case 4:
127 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
128 		return;
129 	case 2:
130 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
131 		return;
132 	case 1:
133 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
134 		return;
135 	default:
136 		panic("clrblock");
137 	}
138 }
139 
140 /*
141  * put a block into the map
142  */
143 setblock(fs, cp, h)
144 	struct fs *fs;
145 	unsigned char *cp;
146 	daddr_t h;
147 {
148 
149 	switch ((int)fs->fs_frag) {
150 
151 	case 8:
152 		cp[h] = 0xff;
153 		return;
154 	case 4:
155 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
156 		return;
157 	case 2:
158 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
159 		return;
160 	case 1:
161 		cp[h >> 3] |= (0x01 << (h & 0x7));
162 		return;
163 	default:
164 		panic("setblock");
165 	}
166 }
167 
168 #ifdef nope
169 #if (!defined(vax) && !defined(tahoe) && !defined(hp300)) \
170 	|| defined(VAX630) || defined(VAX650)
171 /*
172  * C definitions of special instructions.
173  * Normally expanded with inline.
174  */
scanc(size,cp,table,mask)175 scanc(size, cp, table, mask)
176 	u_int size;
177 	register u_char *cp, table[];
178 	register u_char mask;
179 {
180 	register u_char *end = &cp[size];
181 
182 	while (cp < end && (table[*cp] & mask) == 0)
183 		cp++;
184 	return (end - cp);
185 }
186 #endif
187 
188 #if !defined(vax) && !defined(tahoe) && !defined(hp300)
skpc(mask,size,cp)189 skpc(mask, size, cp)
190 	register u_char mask;
191 	u_int size;
192 	register u_char *cp;
193 {
194 	register u_char *end = &cp[size];
195 
196 	while (cp < end && *cp == mask)
197 		cp++;
198 	return (end - cp);
199 }
200 
locc(mask,size,cp)201 locc(mask, size, cp)
202 	register u_char mask;
203 	u_int size;
204 	register u_char *cp;
205 {
206 	register u_char *end = &cp[size];
207 
208 	while (cp < end && *cp != mask)
209 		cp++;
210 	return (end - cp);
211 }
212 #endif
213 #endif
214