1 /* $NetBSD: partitions.c,v 1.13 2021/09/11 20:28:06 andvar Exp $ */
2
3 /*
4 * Copyright (c) 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "defs.h"
30 #include "mbr.h"
31 #include <assert.h>
32
33 /*
34 * A list of partitioning schemes, so we can iterate over everything
35 * supported (e.g. when partitioning a new disk). NULL terminated.
36 */
37 const struct disk_partitioning_scheme **available_part_schemes;
38 /*
39 * The number of valid entries on above list
40 */
41 size_t num_available_part_schemes;
42
43 extern const struct disk_partitioning_scheme disklabel_parts;
44
45 /*
46 * Generic reader - query a disk device and read all partitions from it.
47 * disk_size is in units of physical sector size, which is passe as
48 * bytes_per_sec.
49 */
50 struct disk_partitions *
partitions_read_disk(const char * dev,daddr_t disk_size,size_t bytes_per_sec,bool no_mbr)51 partitions_read_disk(const char *dev, daddr_t disk_size, size_t bytes_per_sec,
52 bool no_mbr)
53 {
54 const struct disk_partitioning_scheme **ps;
55 #ifdef HAVE_MBR
56 bool mbr_done = false, disklabel_done = false;
57 #endif
58
59 if (!available_part_schemes)
60 return NULL;
61
62 for (ps = available_part_schemes; *ps; ps++) {
63 #ifdef HAVE_MBR
64 if (!no_mbr && (*ps) == &disklabel_parts && !mbr_done)
65 continue;
66 if (no_mbr && (*ps)->name == MSG_parttype_mbr)
67 continue;
68 if ((*ps)->name == MSG_parttype_mbr)
69 mbr_done = true;
70 if ((*ps)->read_from_disk == disklabel_parts.read_from_disk)
71 disklabel_done = true;
72 #endif
73 struct disk_partitions *parts =
74 (*ps)->read_from_disk(dev, 0, disk_size, bytes_per_sec,
75 *ps);
76 if (parts)
77 return parts;
78 }
79 #ifdef HAVE_MBR
80 if (!disklabel_done)
81 return disklabel_parts.read_from_disk(dev, 0, disk_size,
82 bytes_per_sec, &disklabel_parts);
83 #endif
84 return NULL;
85 }
86
87 bool
generic_adapt_foreign_part_info(const struct disk_partitions * myself,struct disk_part_info * dest,const struct disk_partitioning_scheme * src_scheme,const struct disk_part_info * src)88 generic_adapt_foreign_part_info(const struct disk_partitions *myself,
89 struct disk_part_info *dest,
90 const struct disk_partitioning_scheme *src_scheme,
91 const struct disk_part_info *src)
92 {
93 *dest = *src;
94 if (myself->pscheme == src_scheme)
95 return true; /* no conversion needed */
96
97 if (src->nat_type == NULL)
98 return false;
99
100 /* slightly simplistic, enhance when needed */
101 dest->nat_type = myself->pscheme->get_fs_part_type(
102 dest->nat_type ? dest->nat_type->generic_ptype : PT_root,
103 dest->fs_type,
104 dest->fs_sub_type);
105 if (dest->nat_type == NULL)
106 dest->nat_type = myself->pscheme->get_generic_part_type(
107 src->nat_type->generic_ptype);
108 if (dest->nat_type == NULL)
109 dest->nat_type = myself->pscheme->create_unknown_part_type();
110 if (dest->nat_type == NULL)
111 dest->nat_type = myself->pscheme->get_generic_part_type(
112 PT_unknown);
113
114 return true;
115 }
116
117 /*************** global init ****************************************/
118 /*
119 * Helper structure to fill our global list of available partitioning
120 * schemes.
121 */
122 struct part_scheme_desc {
123 bool (*is_available)(void);
124 const struct disk_partitioning_scheme *ps;
125 };
126
127 #ifdef HAVE_GPT
128 bool gpt_parts_check(void);
129 extern const struct disk_partitioning_scheme gpt_parts;
130 #endif
131 #ifdef HAVE_MBR
132 extern const struct disk_partitioning_scheme mbr_parts;
133 #endif
134
135 #if RAW_PART == 3
136 static struct disk_partitioning_scheme only_disklabel_parts;
137
138 /*
139 * If not overridden by MD code, we can not boot from plain
140 * disklabel disks (w/o MBR).
141 */
have_only_disklabel_boot_support(const char * disk)142 static bool have_only_disklabel_boot_support(const char *disk)
143 {
144 #ifdef HAVE_PLAIN_DISKLABEL_BOOT
145 return HAVE_PLAIN_DISKLABEL_BOOT(disk);
146 #else
147 return false;
148 #endif
149 }
150 #endif
151
152 /*
153 * One time initialization
154 */
155 void
partitions_init(void)156 partitions_init(void)
157 {
158 /*
159 * List of partitioning schemes.
160 * Order is important, the selection menu is created from start
161 * to end. Keep good defaults early. Most architectures will
162 * only offer very few entries.
163 */
164 static const struct part_scheme_desc all_descs[] = {
165 #if RAW_PART != 3 /* only available as primary on some architectures */
166 { NULL, &disklabel_parts },
167 #endif
168 #ifdef HAVE_GPT
169 { gpt_parts_check, &gpt_parts },
170 #endif
171 #ifdef HAVE_MBR
172 { NULL, &mbr_parts },
173 #endif
174 #if RAW_PART == 3 /* "whole disk NetBSD" disklabel variant */
175 { NULL, &only_disklabel_parts },
176 #endif
177 };
178
179 size_t i, avail;
180 const struct disk_partitioning_scheme **out;
181 bool *is_available;
182 static const size_t all_cnt = __arraycount(all_descs);
183
184 check_available_binaries();
185
186 #if RAW_PART == 3
187 /* generate a variant of disklabel w/o parent scheme */
188 only_disklabel_parts = disklabel_parts;
189 only_disklabel_parts.name = MSG_parttype_only_disklabel;
190 only_disklabel_parts.have_boot_support =
191 have_only_disklabel_boot_support;
192 #endif
193
194
195 is_available = malloc(all_cnt);
196
197 for (avail = i = 0; i < all_cnt; i++) {
198 is_available[i] = all_descs[i].is_available == NULL
199 || all_descs[i].is_available();
200 if (is_available[i])
201 avail++;
202 }
203
204 if (avail == 0)
205 return;
206
207 num_available_part_schemes = avail;
208 available_part_schemes = malloc(sizeof(*available_part_schemes)
209 * (avail+1));
210 if (available_part_schemes == NULL)
211 return;
212
213 for (out = available_part_schemes, i = 0; i < all_cnt; i++) {
214 if (!is_available[i])
215 continue;
216 *out++ = all_descs[i].ps;
217 }
218 *out = NULL;
219
220 free(is_available);
221 }
222
223 /*
224 * Final cleanup
225 */
226 void
partitions_cleanup(void)227 partitions_cleanup(void)
228 {
229 for (size_t i = 0; i < num_available_part_schemes; i++)
230 if (available_part_schemes[i]->cleanup != NULL)
231 available_part_schemes[i]->cleanup();
232 free(available_part_schemes);
233 }
234