xref: /dragonfly/sbin/gpt/create.c (revision 9f7604d7)
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/create.c,v 1.11 2005/08/31 01:47:19 marcel Exp $
27  * $DragonFly: src/sbin/gpt/create.c,v 1.1 2007/06/16 22:29:27 dillon Exp $
28  */
29 
30 #include <sys/types.h>
31 
32 #include <err.h>
33 #include <stddef.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <unistd.h>
38 
39 #include "map.h"
40 #include "gpt.h"
41 
42 static int force;
43 static int primary_only;
44 
45 static void
46 usage_create(void)
47 {
48 
49 	fprintf(stderr,
50 	    "usage: %s [-fp] device ...\n", getprogname());
51 	exit(1);
52 }
53 
54 static void
55 create(int fd)
56 {
57 	uuid_t uuid;
58 	off_t blocks, last;
59 	map_t *gpt, *tpg;
60 	map_t *tbl, *lbt;
61 	map_t *map;
62 	struct mbr *mbr;
63 	struct gpt_hdr *hdr;
64 	struct gpt_ent *ent;
65 	unsigned int i;
66 
67 	last = mediasz / secsz - 1LL;
68 
69 	if (map_find(MAP_TYPE_PRI_GPT_HDR) != NULL ||
70 	    map_find(MAP_TYPE_SEC_GPT_HDR) != NULL) {
71 		warnx("%s: error: device already contains a GPT", device_name);
72 		return;
73 	}
74 	map = map_find(MAP_TYPE_MBR);
75 	if (map != NULL) {
76 		if (!force) {
77 			warnx("%s: error: device contains a MBR", device_name);
78 			return;
79 		}
80 
81 		/* Nuke the MBR in our internal map. */
82 		map->map_type = MAP_TYPE_UNUSED;
83 	}
84 
85 	/*
86 	 * Create PMBR.
87 	 */
88 	if (map_find(MAP_TYPE_PMBR) == NULL) {
89 		if (map_free(0LL, 1LL) == 0) {
90 			warnx("%s: error: no room for the PMBR", device_name);
91 			return;
92 		}
93 		mbr = gpt_read(fd, 0LL, 1);
94 		bzero(mbr, sizeof(*mbr));
95 		mbr->mbr_sig = htole16(MBR_SIG);
96 		mbr->mbr_part[0].part_shd = 0xff;
97 		mbr->mbr_part[0].part_ssect = 0xff;
98 		mbr->mbr_part[0].part_scyl = 0xff;
99 		mbr->mbr_part[0].part_typ = 0xee;
100 		mbr->mbr_part[0].part_ehd = 0xff;
101 		mbr->mbr_part[0].part_esect = 0xff;
102 		mbr->mbr_part[0].part_ecyl = 0xff;
103 		mbr->mbr_part[0].part_start_lo = htole16(1);
104 		if (last > 0xffffffff) {
105 			mbr->mbr_part[0].part_size_lo = htole16(0xffff);
106 			mbr->mbr_part[0].part_size_hi = htole16(0xffff);
107 		} else {
108 			mbr->mbr_part[0].part_size_lo = htole16(last);
109 			mbr->mbr_part[0].part_size_hi = htole16(last >> 16);
110 		}
111 		map = map_add(0LL, 1LL, MAP_TYPE_PMBR, mbr);
112 		gpt_write(fd, map);
113 	}
114 
115 	/* Get the amount of free space after the MBR */
116 	blocks = map_free(1LL, 0LL);
117 	if (blocks == 0LL) {
118 		warnx("%s: error: no room for the GPT header", device_name);
119 		return;
120 	}
121 
122 	/* Don't create more than parts entries. */
123 	if ((uint64_t)(blocks - 1) * secsz > parts * sizeof(struct gpt_ent)) {
124 		blocks = (parts * sizeof(struct gpt_ent)) / secsz;
125 		if ((parts * sizeof(struct gpt_ent)) % secsz)
126 			blocks++;
127 		blocks++;		/* Don't forget the header itself */
128 	}
129 
130 	/* Never cross the median of the device. */
131 	if ((blocks + 1LL) > ((last + 1LL) >> 1))
132 		blocks = ((last + 1LL) >> 1) - 1LL;
133 
134 	/*
135 	 * Get the amount of free space at the end of the device and
136 	 * calculate the size for the GPT structures.
137 	 */
138 	map = map_last();
139 	if (map->map_type != MAP_TYPE_UNUSED) {
140 		warnx("%s: error: no room for the backup header", device_name);
141 		return;
142 	}
143 
144 	if (map->map_size < blocks)
145 		blocks = map->map_size;
146 	if (blocks == 1LL) {
147 		warnx("%s: error: no room for the GPT table", device_name);
148 		return;
149 	}
150 
151 	blocks--;		/* Number of blocks in the GPT table. */
152 	gpt = map_add(1LL, 1LL, MAP_TYPE_PRI_GPT_HDR, calloc(1, secsz));
153 	tbl = map_add(2LL, blocks, MAP_TYPE_PRI_GPT_TBL,
154 	    calloc(blocks, secsz));
155 	if (gpt == NULL || tbl == NULL)
156 		return;
157 
158 	hdr = gpt->map_data;
159 	memcpy(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig));
160 	hdr->hdr_revision = htole32(GPT_HDR_REVISION);
161 	/*
162 	 * XXX struct gpt_hdr is not a multiple of 8 bytes in size and thus
163 	 * contains padding we must not include in the size.
164 	 */
165 	hdr->hdr_size = htole32(offsetof(struct gpt_hdr, padding));
166 	hdr->hdr_lba_self = htole64(gpt->map_start);
167 	hdr->hdr_lba_alt = htole64(last);
168 	hdr->hdr_lba_start = htole64(tbl->map_start + blocks);
169 	hdr->hdr_lba_end = htole64(last - blocks - 1LL);
170 	uuid_create(&uuid, NULL);
171 	le_uuid_enc(&hdr->hdr_uuid, &uuid);
172 	hdr->hdr_lba_table = htole64(tbl->map_start);
173 	hdr->hdr_entries = htole32((blocks * secsz) / sizeof(struct gpt_ent));
174 	if (le32toh(hdr->hdr_entries) > parts)
175 		hdr->hdr_entries = htole32(parts);
176 	hdr->hdr_entsz = htole32(sizeof(struct gpt_ent));
177 
178 	ent = tbl->map_data;
179 	for (i = 0; i < le32toh(hdr->hdr_entries); i++) {
180 		uuid_create(&uuid, NULL);
181 		le_uuid_enc(&ent[i].ent_uuid, &uuid);
182 	}
183 
184 	hdr->hdr_crc_table = htole32(crc32(ent, le32toh(hdr->hdr_entries) *
185 	    le32toh(hdr->hdr_entsz)));
186 	hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
187 
188 	gpt_write(fd, gpt);
189 	gpt_write(fd, tbl);
190 
191 	/*
192 	 * Create backup GPT if the user didn't suppress it.
193 	 */
194 	if (!primary_only) {
195 		tpg = map_add(last, 1LL, MAP_TYPE_SEC_GPT_HDR,
196 		    calloc(1, secsz));
197 		lbt = map_add(last - blocks, blocks, MAP_TYPE_SEC_GPT_TBL,
198 		    tbl->map_data);
199 		memcpy(tpg->map_data, gpt->map_data, secsz);
200 		hdr = tpg->map_data;
201 		hdr->hdr_lba_self = htole64(tpg->map_start);
202 		hdr->hdr_lba_alt = htole64(gpt->map_start);
203 		hdr->hdr_lba_table = htole64(lbt->map_start);
204 		hdr->hdr_crc_self = 0;		/* Don't ever forget this! */
205 		hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
206 		gpt_write(fd, lbt);
207 		gpt_write(fd, tpg);
208 	}
209 }
210 
211 int
212 cmd_create(int argc, char *argv[])
213 {
214 	int ch, fd;
215 
216 	while ((ch = getopt(argc, argv, "fp")) != -1) {
217 		switch(ch) {
218 		case 'f':
219 			force = 1;
220 			break;
221 		case 'p':
222 			primary_only = 1;
223 			break;
224 		default:
225 			usage_create();
226 		}
227 	}
228 
229 	if (argc == optind)
230 		usage_create();
231 
232 	while (optind < argc) {
233 		fd = gpt_open(argv[optind++]);
234 		if (fd == -1) {
235 			warn("unable to open device '%s'", device_name);
236 			continue;
237 		}
238 
239 		create(fd);
240 
241 		gpt_close(fd);
242 	}
243 
244 	return (0);
245 }
246