1
/* pc.c - Read PC style partition tables. */
3
* GRUB -- GRand Unified Bootloader
4
* Copyright (C) 2002,2004,2005 Free Software Foundation, Inc.
6
* GRUB is free software; you can redistribute it and/or modify
7
* it under the terms of the GNU General Public License as published by
8
* the Free Software Foundation; either version 2 of the License, or
9
* (at your option) any later version.
11
* This program 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
14
* GNU General Public License for more details.
16
* You should have received a copy of the GNU General Public License
17
* along with GRUB; if not, write to the Free Software
18
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21
#include <grub/partition.h>
22
#include <grub/pc_partition.h>
23
#include <grub/disk.h>
25
#include <grub/misc.h>
28
static struct grub_partition_map grub_pc_partition_map;
31
static grub_dl_t my_mod;
35
/* Parse the partition representation in STR and return a partition. */
36
static grub_partition_t
37
grub_partition_parse (const char *str)
40
struct grub_pc_partition *pcdata;
42
char *s = (char *) str;
44
p = (grub_partition_t) grub_malloc (sizeof (*p));
48
pcdata = (struct grub_pc_partition *) grub_malloc (sizeof (*pcdata));
53
p->partmap = &grub_pc_partition_map;
55
/* Initialize some of the fields with invalid values. */
56
pcdata->bsd_part = pcdata->dos_type = pcdata->bsd_type = p->index = -1;
58
/* Get the DOS partition number. */
59
pcdata->dos_part = grub_strtoul (s, &s, 0);
63
/* Not found. Maybe only a BSD label is specified. */
64
pcdata->dos_part = -1;
65
grub_errno = GRUB_ERR_NONE;
72
if (*s >= 'a' && *s <= 'h')
74
pcdata->bsd_part = *s - 'a';
82
if (pcdata->dos_part == -1 && pcdata->bsd_part == -1)
90
grub_error (GRUB_ERR_BAD_FILENAME, "invalid partition");
95
pc_partition_map_iterate (grub_disk_t disk,
96
int (*hook) (grub_disk_t disk,
97
const grub_partition_t partition))
99
struct grub_partition p;
100
struct grub_pc_partition pcdata;
101
struct grub_pc_partition_mbr mbr;
102
struct grub_pc_partition_disk_label label;
103
struct grub_disk raw;
105
/* Enforce raw disk access. */
110
pcdata.ext_offset = 0;
111
pcdata.dos_part = -1;
113
p.partmap = &grub_pc_partition_map;
118
struct grub_pc_partition_entry *e;
121
if (grub_disk_read (&raw, p.offset, 0, sizeof (mbr), (char *) &mbr))
124
/* Check if it is valid. */
125
if (mbr.signature != grub_cpu_to_le16 (GRUB_PC_PARTITION_SIGNATURE))
126
return grub_error (GRUB_ERR_BAD_PART_TABLE, "no signature");
128
/* Analyze DOS partitions. */
129
for (p.index = 0; p.index < 4; p.index++)
131
e = mbr.entries + p.index;
133
p.start = p.offset + grub_le_to_cpu32 (e->start);
134
p.len = grub_le_to_cpu32 (e->length);
135
pcdata.bsd_part = -1;
136
pcdata.dos_type = e->type;
137
pcdata.bsd_type = -1;
139
grub_dprintf ("partition",
140
"partition %d: flag 0x%x, type 0x%x, start 0x%lx, len 0x%lx\n",
141
p.index, e->flag, pcdata.dos_type, p.start, p.len);
143
/* If this is a GPT partition, this MBR is just a dummy. */
144
if (e->type == GRUB_PC_PARTITION_TYPE_GPT_DISK && p.index == 0)
145
return grub_error (GRUB_ERR_BAD_PART_TABLE, "dummy mbr");
147
/* If this partition is a normal one, call the hook. */
148
if (! grub_pc_partition_is_empty (e->type)
149
&& ! grub_pc_partition_is_extended (e->type))
156
/* Check if this is a BSD partition. */
157
if (grub_pc_partition_is_bsd (e->type))
159
/* Check if the BSD label is within the DOS partition. */
160
if (p.len <= GRUB_PC_PARTITION_BSD_LABEL_SECTOR)
161
return grub_error (GRUB_ERR_BAD_PART_TABLE,
162
"no space for disk label");
164
/* Read the BSD label. */
165
if (grub_disk_read (&raw,
167
+ GRUB_PC_PARTITION_BSD_LABEL_SECTOR),
173
/* Check if it is valid. */
175
!= grub_cpu_to_le32 (GRUB_PC_PARTITION_BSD_LABEL_MAGIC))
176
return grub_error (GRUB_ERR_BAD_PART_TABLE,
177
"invalid disk label magic 0x%x",
180
for (pcdata.bsd_part = 0;
181
pcdata.bsd_part < grub_cpu_to_le16 (label.num_partitions);
184
struct grub_pc_partition_bsd_entry *be
185
= label.entries + pcdata.bsd_part;
187
p.start = grub_le_to_cpu32 (be->offset);
188
p.len = grub_le_to_cpu32 (be->size);
189
pcdata.bsd_type = be->fs_type;
191
if (be->fs_type != GRUB_PC_PARTITION_BSD_TYPE_UNUSED)
197
else if (pcdata.dos_part < 4)
198
/* If this partition is a logical one, shouldn't increase the
203
/* Find an extended partition. */
204
for (i = 0; i < 4; i++)
208
if (grub_pc_partition_is_extended (e->type))
210
p.offset = pcdata.ext_offset + grub_le_to_cpu32 (e->start);
211
if (! pcdata.ext_offset)
212
pcdata.ext_offset = p.offset;
218
/* If no extended partition, the end. */
228
static grub_partition_t
229
pc_partition_map_probe (grub_disk_t disk, const char *str)
232
struct grub_pc_partition *pcdata;
234
auto int find_func (grub_disk_t d, const grub_partition_t partition);
236
int find_func (grub_disk_t d __attribute__ ((unused)),
237
const grub_partition_t partition)
239
struct grub_pc_partition *partdata = partition->data;
240
if ((pcdata->dos_part == partdata->dos_part || pcdata->dos_part == -1)
241
&& pcdata->bsd_part == partdata->bsd_part)
243
grub_memcpy (p, partition, sizeof (*p));
245
grub_memcpy (pcdata, partdata, sizeof (*pcdata));
252
p = grub_partition_parse (str);
257
if (pc_partition_map_iterate (disk, find_func))
262
grub_error (GRUB_ERR_BAD_DEVICE, "no such partition");
276
pc_partition_map_get_name (const grub_partition_t p)
279
struct grub_pc_partition *pcdata = p->data;
281
name = grub_malloc (13);
285
if (pcdata->bsd_part < 0)
286
grub_sprintf (name, "%d", pcdata->dos_part);
288
grub_sprintf (name, "%d,%c", pcdata->dos_part, pcdata->bsd_part + 'a');
294
/* Partition map type. */
295
static struct grub_partition_map grub_pc_partition_map =
297
.name = "pc_partition_map",
298
.iterate = pc_partition_map_iterate,
299
.probe = pc_partition_map_probe,
300
.get_name = pc_partition_map_get_name
303
GRUB_MOD_INIT(pc_partition_map)
305
grub_partition_map_register (&grub_pc_partition_map);
311
GRUB_MOD_FINI(pc_partition_map)
313
grub_partition_map_unregister (&grub_pc_partition_map);