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 */
46void
47ffs_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 */
82int
83ffs_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 */
110int
111ffs_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 */
132void
133ffs_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 */
158void
159ffs_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