xref: /netbsd-src/sbin/gpt/create.c (revision f89f6560d453f5e37386cc7938c072d2f528b9fa)
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 
27 #if HAVE_NBTOOL_CONFIG_H
28 #include "nbtool_config.h"
29 #endif
30 
31 #include <sys/cdefs.h>
32 #ifdef __FBSDID
33 __FBSDID("$FreeBSD: src/sbin/gpt/create.c,v 1.11 2005/08/31 01:47:19 marcel Exp $");
34 #endif
35 #ifdef __RCSID
36 __RCSID("$NetBSD: create.c,v 1.12 2014/10/03 20:30:06 christos Exp $");
37 #endif
38 
39 #include <sys/types.h>
40 #include <sys/bootblock.h>
41 
42 #include <err.h>
43 #include <stddef.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "map.h"
50 #include "gpt.h"
51 
52 static int force;
53 static int primary_only;
54 
55 const char createmsg[] = "create [-fp] device ...";
56 
57 __dead static void
58 usage_create(void)
59 {
60 
61 	fprintf(stderr,
62 	    "usage: %s %s\n", getprogname(), createmsg);
63 	exit(1);
64 }
65 
66 static void
67 create(int fd)
68 {
69 	off_t blocks, last;
70 	map_t *gpt, *tpg;
71 	map_t *tbl, *lbt;
72 	map_t *map;
73 	struct mbr *mbr;
74 	struct gpt_hdr *hdr;
75 	struct gpt_ent *ent;
76 	unsigned int i;
77 
78 	last = mediasz / secsz - 1LL;
79 
80 	if (map_find(MAP_TYPE_PRI_GPT_HDR) != NULL ||
81 	    map_find(MAP_TYPE_SEC_GPT_HDR) != NULL) {
82 		warnx("%s: error: device already contains a GPT", device_name);
83 		return;
84 	}
85 	map = map_find(MAP_TYPE_MBR);
86 	if (map != NULL) {
87 		if (!force) {
88 			warnx("%s: error: device contains a MBR", device_name);
89 			return;
90 		}
91 
92 		/* Nuke the MBR in our internal map. */
93 		map->map_type = MAP_TYPE_UNUSED;
94 	}
95 
96 	/*
97 	 * Create PMBR.
98 	 */
99 	if (map_find(MAP_TYPE_PMBR) == NULL) {
100 		if (map_free(0LL, 1LL) == 0) {
101 			warnx("%s: error: no room for the PMBR", device_name);
102 			return;
103 		}
104 		mbr = gpt_read(fd, 0LL, 1);
105 		memset(mbr, 0, sizeof(*mbr));
106 		mbr->mbr_sig = htole16(MBR_SIG);
107 		mbr->mbr_part[0].part_shd = 0x00;
108 		mbr->mbr_part[0].part_ssect = 0x02;
109 		mbr->mbr_part[0].part_scyl = 0x00;
110 		mbr->mbr_part[0].part_typ = MBR_PTYPE_PMBR;
111 		mbr->mbr_part[0].part_ehd = 0xfe;
112 		mbr->mbr_part[0].part_esect = 0xff;
113 		mbr->mbr_part[0].part_ecyl = 0xff;
114 		mbr->mbr_part[0].part_start_lo = htole16(1);
115 		if (last > 0xffffffff) {
116 			mbr->mbr_part[0].part_size_lo = htole16(0xffff);
117 			mbr->mbr_part[0].part_size_hi = htole16(0xffff);
118 		} else {
119 			mbr->mbr_part[0].part_size_lo = htole16(last);
120 			mbr->mbr_part[0].part_size_hi = htole16(last >> 16);
121 		}
122 		map = map_add(0LL, 1LL, MAP_TYPE_PMBR, mbr);
123 		gpt_write(fd, map);
124 	}
125 
126 	/* Get the amount of free space after the MBR */
127 	blocks = map_free(1LL, 0LL);
128 	if (blocks == 0LL) {
129 		warnx("%s: error: no room for the GPT header", device_name);
130 		return;
131 	}
132 
133 	/* Don't create more than parts entries. */
134 	if ((uint64_t)(blocks - 1) * secsz > parts * sizeof(struct gpt_ent)) {
135 		blocks = (parts * sizeof(struct gpt_ent)) / secsz;
136 		if ((parts * sizeof(struct gpt_ent)) % secsz)
137 			blocks++;
138 		blocks++;		/* Don't forget the header itself */
139 	}
140 
141 	/* Never cross the median of the device. */
142 	if ((blocks + 1LL) > ((last + 1LL) >> 1))
143 		blocks = ((last + 1LL) >> 1) - 1LL;
144 
145 	/*
146 	 * Get the amount of free space at the end of the device and
147 	 * calculate the size for the GPT structures.
148 	 */
149 	map = map_last();
150 	if (map->map_type != MAP_TYPE_UNUSED) {
151 		warnx("%s: error: no room for the backup header", device_name);
152 		return;
153 	}
154 
155 	if (map->map_size < blocks)
156 		blocks = map->map_size;
157 	if (blocks == 1LL) {
158 		warnx("%s: error: no room for the GPT table", device_name);
159 		return;
160 	}
161 
162 	blocks--;		/* Number of blocks in the GPT table. */
163 	gpt = map_add(1LL, 1LL, MAP_TYPE_PRI_GPT_HDR, calloc(1, secsz));
164 	tbl = map_add(2LL, blocks, MAP_TYPE_PRI_GPT_TBL,
165 	    calloc(blocks, secsz));
166 	if (gpt == NULL || tbl == NULL)
167 		return;
168 
169 	hdr = gpt->map_data;
170 	memcpy(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig));
171 	hdr->hdr_revision = htole32(GPT_HDR_REVISION);
172 	hdr->hdr_size = htole32(GPT_HDR_SIZE);
173 	hdr->hdr_lba_self = htole64(gpt->map_start);
174 	hdr->hdr_lba_alt = htole64(last);
175 	hdr->hdr_lba_start = htole64(tbl->map_start + blocks);
176 	hdr->hdr_lba_end = htole64(last - blocks - 1LL);
177 	gpt_uuid_generate(hdr->hdr_guid);
178 	hdr->hdr_lba_table = htole64(tbl->map_start);
179 	hdr->hdr_entries = htole32((blocks * secsz) / sizeof(struct gpt_ent));
180 	if (le32toh(hdr->hdr_entries) > parts)
181 		hdr->hdr_entries = htole32(parts);
182 	hdr->hdr_entsz = htole32(sizeof(struct gpt_ent));
183 
184 	ent = tbl->map_data;
185 	for (i = 0; i < le32toh(hdr->hdr_entries); i++) {
186 		gpt_uuid_generate(ent[i].ent_guid);
187 	}
188 
189 	hdr->hdr_crc_table = htole32(crc32(ent, le32toh(hdr->hdr_entries) *
190 	    le32toh(hdr->hdr_entsz)));
191 	hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
192 
193 	gpt_write(fd, gpt);
194 	gpt_write(fd, tbl);
195 
196 	/*
197 	 * Create backup GPT if the user didn't suppress it.
198 	 */
199 	if (!primary_only) {
200 		tpg = map_add(last, 1LL, MAP_TYPE_SEC_GPT_HDR,
201 		    calloc(1, secsz));
202 		lbt = map_add(last - blocks, blocks, MAP_TYPE_SEC_GPT_TBL,
203 		    tbl->map_data);
204 		memcpy(tpg->map_data, gpt->map_data, secsz);
205 		hdr = tpg->map_data;
206 		hdr->hdr_lba_self = htole64(tpg->map_start);
207 		hdr->hdr_lba_alt = htole64(gpt->map_start);
208 		hdr->hdr_lba_table = htole64(lbt->map_start);
209 		hdr->hdr_crc_self = 0;		/* Don't ever forget this! */
210 		hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
211 		gpt_write(fd, lbt);
212 		gpt_write(fd, tpg);
213 	}
214 }
215 
216 int
217 cmd_create(int argc, char *argv[])
218 {
219 	int ch, fd;
220 
221 	while ((ch = getopt(argc, argv, "fp")) != -1) {
222 		switch(ch) {
223 		case 'f':
224 			force = 1;
225 			break;
226 		case 'p':
227 			primary_only = 1;
228 			break;
229 		default:
230 			usage_create();
231 		}
232 	}
233 
234 	if (argc == optind)
235 		usage_create();
236 
237 	while (optind < argc) {
238 		fd = gpt_open(argv[optind++]);
239 		if (fd == -1) {
240 			warn("unable to open device '%s'", device_name);
241 			continue;
242 		}
243 
244 		create(fd);
245 
246 		gpt_close(fd);
247 	}
248 
249 	return (0);
250 }
251