xref: /dragonfly/sbin/gpt/map.c (revision 35a9ab8af19377d7d13017c9cefc41eb33a342ec)
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  */
28 
29 #include <sys/param.h>
30 #include <err.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 
34 #include "map.h"
35 
36 #define ROUNDTO 2048          // must be a power of two
37 #define ROUNDDOWN(x) rounddown2(x - 1, ROUNDTO)
38 #define ROUNDUP(x) (ROUNDDOWN(x) + ROUNDTO)
39 
40 int lbawidth;
41 
42 static map_t *mediamap;
43 
44 map_t *
mkmap(off_t start,off_t size,int type)45 mkmap(off_t start, off_t size, int type)
46 {
47           map_t *m;
48 
49           m = malloc(sizeof(*m));
50           if (m == NULL)
51                     return (NULL);
52           m->map_start = start;
53           m->map_size = size;
54           m->map_next = m->map_prev = NULL;
55           m->map_type = type;
56           m->map_index = NOENTRY;
57           m->map_data = NULL;
58           return (m);
59 }
60 
61 map_t *
map_add(off_t start,off_t size,int type,void * data)62 map_add(off_t start, off_t size, int type, void *data)
63 {
64           map_t *m, *n, *p;
65 
66           n = mediamap;
67           while (n != NULL && n->map_start + n->map_size <= start)
68                     n = n->map_next;
69           if (n == NULL)
70                     return (NULL);
71 
72           if (n->map_start + n->map_size < start + size) {
73                     warnx("error: bogus map");
74                     return (0);
75           }
76 
77           if (n->map_start == start && n->map_size == size) {
78                     if (n->map_type != MAP_TYPE_UNUSED) {
79                               if (n->map_type != MAP_TYPE_MBR_PART ||
80                                   type != MAP_TYPE_GPT_PART) {
81                                         warnx("warning: partition(%llu,%llu) mirrored",
82                                             (long long)start, (long long)size);
83                               }
84                     }
85                     n->map_type = type;
86                     n->map_data = data;
87                     return (n);
88           }
89 
90           if (n->map_type != MAP_TYPE_UNUSED) {
91                     if (n->map_type != MAP_TYPE_MBR_PART ||
92                         type != MAP_TYPE_GPT_PART) {
93                               warnx("error: bogus map");
94                               return (0);
95                     }
96                     n->map_type = MAP_TYPE_UNUSED;
97           }
98 
99           m = mkmap(start, size, type);
100           if (m == NULL)
101                     return (NULL);
102 
103           m->map_data = data;
104 
105           if (start == n->map_start) {
106                     m->map_prev = n->map_prev;
107                     m->map_next = n;
108                     if (m->map_prev != NULL)
109                               m->map_prev->map_next = m;
110                     else
111                               mediamap = m;
112                     n->map_prev = m;
113                     n->map_start += size;
114                     n->map_size -= size;
115           } else if (start + size == n->map_start + n->map_size) {
116                     p = n;
117                     m->map_next = p->map_next;
118                     m->map_prev = p;
119                     if (m->map_next != NULL)
120                               m->map_next->map_prev = m;
121                     p->map_next = m;
122                     p->map_size -= size;
123           } else {
124                     p = mkmap(n->map_start, start - n->map_start, n->map_type);
125                     n->map_start += p->map_size + m->map_size;
126                     n->map_size -= (p->map_size + m->map_size);
127                     p->map_prev = n->map_prev;
128                     m->map_prev = p;
129                     n->map_prev = m;
130                     m->map_next = n;
131                     p->map_next = m;
132                     if (p->map_prev != NULL)
133                               p->map_prev->map_next = p;
134                     else
135                               mediamap = p;
136           }
137 
138           return (m);
139 }
140 
141 map_t *
map_alloc(off_t start,off_t size)142 map_alloc(off_t start, off_t size)
143 {
144           off_t delta;
145           map_t *m;
146 
147           if (start == 0 && size != 0)
148                     size = ROUNDUP(size);
149           for (m = mediamap; m != NULL; m = m->map_next) {
150                     if (m->map_type != MAP_TYPE_UNUSED || m->map_start < 2)
151                               continue;
152                     if (start != 0 && m->map_start > start)
153                               return (NULL);
154                     delta = (start != 0) ? start - m->map_start : ROUNDUP(m->map_start) - m->map_start;
155                     if (size == 0 || m->map_size - delta >= size) {
156                               if (m->map_size - delta <= 0)
157                                         continue;
158                               if (size == 0) {
159                                         size = m->map_size - delta;
160                                         if (start == 0)
161                                                   size = ROUNDDOWN(size);
162                               }
163                               return (map_add(m->map_start + delta, size,
164                                             MAP_TYPE_GPT_PART, NULL));
165                     }
166           }
167 
168           return (NULL);
169 }
170 
171 map_t *
map_find(int type)172 map_find(int type)
173 {
174           map_t *m;
175 
176           m = mediamap;
177           while (m != NULL && m->map_type != type)
178                     m = m->map_next;
179           return (m);
180 }
181 
182 map_t *
map_first(void)183 map_first(void)
184 {
185           return mediamap;
186 }
187 
188 map_t *
map_last(void)189 map_last(void)
190 {
191           map_t *m;
192 
193           m = mediamap;
194           while (m != NULL && m->map_next != NULL)
195                     m = m->map_next;
196           return (m);
197 }
198 
199 off_t
map_free(off_t start,off_t size)200 map_free(off_t start, off_t size)
201 {
202           map_t *m;
203 
204           m = mediamap;
205 
206           while (m != NULL && m->map_start + m->map_size <= start)
207                     m = m->map_next;
208           if (m == NULL || m->map_type != MAP_TYPE_UNUSED)
209                     return (0LL);
210           if (size)
211                     return ((m->map_start + m->map_size >= start + size) ? 1 : 0);
212           return (m->map_size - (start - m->map_start));
213 }
214 
215 void
map_init(off_t size)216 map_init(off_t size)
217 {
218           char buf[32];
219 
220           mediamap = mkmap(0LL, size, MAP_TYPE_UNUSED);
221           lbawidth = sprintf(buf, "%llu", (long long)size);
222           if (lbawidth < 5)
223                     lbawidth = 5;
224 }
225