xref: /dragonfly/sbin/gpt/map.c (revision cae2835b)
1 /*-
2  * Copyright (c) 2002 Marcel Moolenaar
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  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD: src/sbin/gpt/map.c,v 1.6 2005/08/31 01:47:19 marcel Exp $
27  * $DragonFly: src/sbin/gpt/map.c,v 1.2 2007/06/17 08:34:59 dillon Exp $
28  */
29 
30 #include <sys/types.h>
31 #include <err.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 
35 #include "map.h"
36 
37 #define ROUNDTO 2048	// must be a power of two
38 #define ROUNDDOWN(x) ((x-1) & ~(ROUNDTO-1))
39 #define ROUNDUP(x) (ROUNDDOWN(x) + ROUNDTO)
40 
41 int lbawidth;
42 
43 static map_t *mediamap;
44 
45 static map_t *
46 mkmap(off_t start, off_t size, int type)
47 {
48 	map_t *m;
49 
50 	m = malloc(sizeof(*m));
51 	if (m == NULL)
52 		return (NULL);
53 	m->map_start = start;
54 	m->map_size = size;
55 	m->map_next = m->map_prev = NULL;
56 	m->map_type = type;
57 	m->map_index = NOENTRY;
58 	m->map_data = NULL;
59 	return (m);
60 }
61 
62 map_t *
63 map_add(off_t start, off_t size, int type, void *data)
64 {
65 	map_t *m, *n, *p;
66 
67 	n = mediamap;
68 	while (n != NULL && n->map_start + n->map_size <= start)
69 		n = n->map_next;
70 	if (n == NULL)
71 		return (NULL);
72 
73 	if (n->map_start + n->map_size < start + size) {
74 		warnx("error: bogus map");
75 		return (0);
76 	}
77 
78 	if (n->map_start == start && n->map_size == size) {
79 		if (n->map_type != MAP_TYPE_UNUSED) {
80 			if (n->map_type != MAP_TYPE_MBR_PART ||
81 			    type != MAP_TYPE_GPT_PART) {
82 				warnx("warning: partition(%llu,%llu) mirrored",
83 				    (long long)start, (long long)size);
84 			}
85 		}
86 		n->map_type = type;
87 		n->map_data = data;
88 		return (n);
89 	}
90 
91 	if (n->map_type != MAP_TYPE_UNUSED) {
92 		if (n->map_type != MAP_TYPE_MBR_PART ||
93 		    type != MAP_TYPE_GPT_PART) {
94 			warnx("error: bogus map");
95 			return (0);
96 		}
97 		n->map_type = MAP_TYPE_UNUSED;
98 	}
99 
100 	m = mkmap(start, size, type);
101 	if (m == NULL)
102 		return (NULL);
103 
104 	m->map_data = data;
105 
106 	if (start == n->map_start) {
107 		m->map_prev = n->map_prev;
108 		m->map_next = n;
109 		if (m->map_prev != NULL)
110 			m->map_prev->map_next = m;
111 		else
112 			mediamap = m;
113 		n->map_prev = m;
114 		n->map_start += size;
115 		n->map_size -= size;
116 	} else if (start + size == n->map_start + n->map_size) {
117 		p = n;
118 		m->map_next = p->map_next;
119 		m->map_prev = p;
120 		if (m->map_next != NULL)
121 			m->map_next->map_prev = m;
122 		p->map_next = m;
123 		p->map_size -= size;
124 	} else {
125 		p = mkmap(n->map_start, start - n->map_start, n->map_type);
126 		n->map_start += p->map_size + m->map_size;
127 		n->map_size -= (p->map_size + m->map_size);
128 		p->map_prev = n->map_prev;
129 		m->map_prev = p;
130 		n->map_prev = m;
131 		m->map_next = n;
132 		p->map_next = m;
133 		if (p->map_prev != NULL)
134 			p->map_prev->map_next = p;
135 		else
136 			mediamap = p;
137 	}
138 
139 	return (m);
140 }
141 
142 map_t *
143 map_alloc(off_t start, off_t size)
144 {
145 	off_t delta;
146 	map_t *m;
147 
148 	if (start == 0 && size != 0)
149 		size = ROUNDUP(size);
150 	for (m = mediamap; m != NULL; m = m->map_next) {
151 		if (m->map_type != MAP_TYPE_UNUSED || m->map_start < 2)
152 			continue;
153 		if (start != 0 && m->map_start > start)
154 			return (NULL);
155 		delta = (start != 0) ? start - m->map_start : ROUNDUP(m->map_start) - m->map_start;
156 		if (size == 0 || m->map_size - delta >= size) {
157 			if (m->map_size - delta <= 0)
158 				continue;
159 			if (size == 0) {
160 				size = m->map_size - delta;
161 				if (start == 0)
162 					size = ROUNDDOWN(size);
163 			}
164 			return (map_add(m->map_start + delta, size,
165 				    MAP_TYPE_GPT_PART, NULL));
166 		}
167 	}
168 
169 	return (NULL);
170 }
171 
172 map_t *
173 map_find(int type)
174 {
175 	map_t *m;
176 
177 	m = mediamap;
178 	while (m != NULL && m->map_type != type)
179 		m = m->map_next;
180 	return (m);
181 }
182 
183 map_t *
184 map_first(void)
185 {
186 	return mediamap;
187 }
188 
189 map_t *
190 map_last(void)
191 {
192 	map_t *m;
193 
194 	m = mediamap;
195 	while (m != NULL && m->map_next != NULL)
196 		m = m->map_next;
197 	return (m);
198 }
199 
200 off_t
201 map_free(off_t start, off_t size)
202 {
203 	map_t *m;
204 
205 	m = mediamap;
206 
207 	while (m != NULL && m->map_start + m->map_size <= start)
208 		m = m->map_next;
209 	if (m == NULL || m->map_type != MAP_TYPE_UNUSED)
210 		return (0LL);
211 	if (size)
212 		return ((m->map_start + m->map_size >= start + size) ? 1 : 0);
213 	return (m->map_size - (start - m->map_start));
214 }
215 
216 void
217 map_init(off_t size)
218 {
219 	char buf[32];
220 
221 	mediamap = mkmap(0LL, size, MAP_TYPE_UNUSED);
222 	lbawidth = sprintf(buf, "%llu", (long long)size);
223 	if (lbawidth < 5)
224 		lbawidth = 5;
225 }
226