2 * volume_id - reads filesystem label and uuid
4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 //kbuild:### lib-$(CONFIG_FEATURE_VOLUMEID_MSDOS) += msdos.o
23 //config:### config FEATURE_VOLUMEID_MSDOS
24 //config:### bool "msdos filesystem"
25 //config:### default y
26 //config:### depends on VOLUMEID
28 #include "volume_id_internal.h"
30 struct msdos_partition_entry {
43 #define MSDOS_PARTTABLE_OFFSET 0x1be
44 #define MSDOS_SIG_OFF 0x1fe
46 #define DOS_EXTENDED_PARTITION 0x05
47 #define LINUX_EXTENDED_PARTITION 0x85
48 #define WIN98_EXTENDED_PARTITION 0x0f
49 #define LINUX_RAID_PARTITION 0xfd
50 #define is_extended(type) \
51 (type == DOS_EXTENDED_PARTITION || \
52 type == WIN98_EXTENDED_PARTITION || \
53 type == LINUX_EXTENDED_PARTITION)
54 #define is_raid(type) \
55 (type == LINUX_RAID_PARTITION)
57 int FAST_FUNC volume_id_probe_msdos_part_table(struct volume_id *id, uint64_t off)
63 uint64_t extended = 0;
68 struct msdos_partition_entry *part;
69 struct volume_id_partition *p;
71 dbg("probing at offset 0x%llx", (unsigned long long) off);
73 buf = volume_id_get_buffer(id, off, 0x200);
77 if (buf[MSDOS_SIG_OFF] != 0x55 || buf[MSDOS_SIG_OFF + 1] != 0xaa)
80 /* check flags on all entries for a valid partition table */
81 part = (struct msdos_partition_entry*) &buf[MSDOS_PARTTABLE_OFFSET];
82 for (i = 0; i < 4; i++) {
83 if (part[i].boot_ind != 0
84 && part[i].boot_ind != 0x80
89 if (part[i].nr_sects != 0)
95 if (id->partitions != NULL)
97 id->partitions = xzalloc(VOLUME_ID_PARTITIONS_MAX *
98 sizeof(struct volume_id_partition));
100 for (i = 0; i < 4; i++) {
101 poff = (uint64_t) le32_to_cpu(part[i].start_sect) * BSIZE;
102 plen = (uint64_t) le32_to_cpu(part[i].nr_sects) * BSIZE;
107 p = &id->partitions[i];
109 // p->pt_type_raw = part[i].sys_ind;
111 if (is_extended(part[i].sys_ind)) {
112 dbg("found extended partition at 0x%llx", (unsigned long long) poff);
113 // volume_id_set_usage_part(p, VOLUME_ID_PARTITIONTABLE);
114 // p->type = "msdos_extended_partition";
116 extended = off + poff;
118 dbg("found 0x%x data partition at 0x%llx, len 0x%llx",
119 part[i].sys_ind, (unsigned long long) poff, (unsigned long long) plen);
121 // if (is_raid(part[i].sys_ind))
122 // volume_id_set_usage_part(p, VOLUME_ID_RAID);
124 // volume_id_set_usage_part(p, VOLUME_ID_UNPROBED);
127 // p->pt_off = off + poff;
129 id->partition_count = i+1;
136 /* follow extended partition chain and add data partitions */
139 dbg("extended chain limit reached");
143 buf = volume_id_get_buffer(id, current, 0x200);
147 part = (struct msdos_partition_entry*) &buf[MSDOS_PARTTABLE_OFFSET];
149 if (buf[MSDOS_SIG_OFF] != 0x55 || buf[MSDOS_SIG_OFF + 1] != 0xaa)
154 for (i = 0; i < 4; i++) {
155 poff = (uint64_t) le32_to_cpu(part[i].start_sect) * BSIZE;
156 plen = (uint64_t) le32_to_cpu(part[i].nr_sects) * BSIZE;
161 if (is_extended(part[i].sys_ind)) {
162 dbg("found extended partition at 0x%llx", (unsigned long long) poff);
164 next = extended + poff;
166 dbg("found 0x%x data partition at 0x%llx, len 0x%llx",
167 part[i].sys_ind, (unsigned long long) poff, (unsigned long long) plen);
169 /* we always start at the 5th entry */
170 // while (id->partition_count < 4)
171 // volume_id_set_usage_part(&id->partitions[id->partition_count++], VOLUME_ID_UNUSED);
172 if (id->partition_count < 4)
173 id->partition_count = 4;
175 // p = &id->partitions[id->partition_count];
177 // if (is_raid(part[i].sys_ind))
178 // volume_id_set_usage_part(p, VOLUME_ID_RAID);
180 // volume_id_set_usage_part(p, VOLUME_ID_UNPROBED);
182 // p->pt_off = current + poff;
184 id->partition_count++;
186 // p->pt_type_raw = part[i].sys_ind;
188 if (id->partition_count >= VOLUME_ID_PARTITIONS_MAX) {
189 dbg("too many partitions");
198 // volume_id_set_usage(id, VOLUME_ID_PARTITIONTABLE);
199 // id->type = "msdos_partition_table";