1 /* gptsync.c - fill the mbr based on gpt entries */
2 /* XXX: I don't know what to do if sector size isn't 512 bytes */
4 * GRUB -- GRand Unified Bootloader
5 * Copyright (C) 2009 Free Software Foundation, Inc.
7 * GRUB is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
12 * GRUB is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
21 #include <grub/command.h>
23 #include <grub/device.h>
24 #include <grub/disk.h>
25 #include <grub/msdos_partition.h>
26 #include <grub/partition.h>
27 #include <grub/misc.h>
30 #include <grub/i18n.h>
32 /* Convert a LBA address to a CHS address in the INT 13 format. */
33 /* Taken from grub1. */
34 /* XXX: use hardcoded geometry of C = 1024, H = 255, S = 63.
38 lba_to_chs (int lba
, grub_uint8_t
*cl
, grub_uint8_t
*ch
,
41 int cylinder
, head
, sector
;
42 int sectors
= 63, heads
= 255, cylinders
= 1024;
44 sector
= lba
% sectors
+ 1;
45 head
= (lba
/ sectors
) % heads
;
46 cylinder
= lba
/ (sectors
* heads
);
48 if (cylinder
>= cylinders
)
50 *cl
= *ch
= *dh
= 0xff;
54 *cl
= sector
| ((cylinder
& 0x300) >> 2);
55 *ch
= cylinder
& 0xFF;
60 grub_cmd_gptsync (grub_command_t cmd
__attribute__ ((unused
)),
61 int argc
, char **args
)
64 struct grub_msdos_partition_mbr mbr
;
65 struct grub_partition
*partition
;
66 grub_disk_addr_t first_sector
;
70 return grub_error (GRUB_ERR_BAD_ARGUMENT
, "device name required");
72 return grub_error (GRUB_ERR_BAD_ARGUMENT
, "only 3 partitions can be "
75 if (args
[0][0] == '(' && args
[0][grub_strlen (args
[0]) - 1] == ')')
77 args
[0][grub_strlen (args
[0]) - 1] = 0;
78 dev
= grub_device_open (args
[0] + 1);
79 args
[0][grub_strlen (args
[0])] = ')';
82 dev
= grub_device_open (args
[0]);
89 grub_device_close (dev
);
90 return grub_error (GRUB_ERR_BAD_ARGUMENT
, "not a disk");
93 /* Read the protective MBR. */
94 if (grub_disk_read (dev
->disk
, 0, 0, sizeof (mbr
), &mbr
))
96 grub_device_close (dev
);
100 /* Check if it is valid. */
101 if (mbr
.signature
!= grub_cpu_to_le16 (GRUB_PC_PARTITION_SIGNATURE
))
103 grub_device_close (dev
);
104 return grub_error (GRUB_ERR_BAD_PART_TABLE
, "no signature");
107 /* Make sure the MBR is a protective MBR and not a normal MBR. */
108 if (mbr
.entries
[0].type
!= GRUB_PC_PARTITION_TYPE_GPT_DISK
)
110 grub_device_close (dev
);
111 return grub_error (GRUB_ERR_BAD_PART_TABLE
, "no GPT partition map found");
115 first_sector
= dev
->disk
->total_sectors
;
116 for (i
= 1; i
< argc
; i
++)
118 char *separator
, csep
= 0;
120 separator
= grub_strchr (args
[i
], '+');
122 separator
= grub_strchr (args
[i
], '-');
128 partition
= grub_partition_probe (dev
->disk
, args
[i
]);
133 grub_device_close (dev
);
134 return grub_error (GRUB_ERR_UNKNOWN_DEVICE
, "no such partition");
137 if (partition
->start
+ partition
->len
> 0xffffffff)
139 grub_device_close (dev
);
140 return grub_error (GRUB_ERR_OUT_OF_RANGE
,
141 "only partitions residing in the first 2TB "
142 "can be present in hybrid MBR");
146 if (first_sector
> partition
->start
)
147 first_sector
= partition
->start
;
149 if (separator
&& *(separator
+ 1))
150 type
= grub_strtoul (separator
+ 1, 0, 0);
154 dev
->disk
->partition
= partition
;
155 fs
= grub_fs_probe (dev
);
157 /* Unknown filesystem isn't fatal. */
158 if (grub_errno
== GRUB_ERR_UNKNOWN_FS
)
161 grub_errno
= GRUB_ERR_NONE
;
164 if (fs
&& grub_strcmp (fs
->name
, "ntfs") == 0)
165 type
= GRUB_PC_PARTITION_TYPE_NTFS
;
166 else if (fs
&& grub_strcmp (fs
->name
, "fat") == 0)
167 /* FIXME: detect FAT16. */
168 type
= GRUB_PC_PARTITION_TYPE_FAT32_LBA
;
169 else if (fs
&& (grub_strcmp (fs
->name
, "hfsplus") == 0
170 || grub_strcmp (fs
->name
, "hfs") == 0))
171 type
= GRUB_PC_PARTITION_TYPE_HFS
;
173 /* FIXME: detect more types. */
174 type
= GRUB_PC_PARTITION_TYPE_EXT2FS
;
176 dev
->disk
->partition
= 0;
179 mbr
.entries
[i
].flag
= (csep
== '+') ? 0x80 : 0;
185 grub_device_close (dev
);
186 return grub_error (GRUB_ERR_BAD_ARGUMENT
,
187 "only one partition can be active");
190 mbr
.entries
[i
].type
= type
;
191 mbr
.entries
[i
].start
= grub_cpu_to_le32 (partition
->start
);
192 lba_to_chs (partition
->start
,
193 &(mbr
.entries
[i
].start_sector
),
194 &(mbr
.entries
[i
].start_cylinder
),
195 &(mbr
.entries
[i
].start_head
));
196 lba_to_chs (partition
->start
+ partition
->len
- 1,
197 &(mbr
.entries
[i
].end_sector
),
198 &(mbr
.entries
[i
].end_cylinder
),
199 &(mbr
.entries
[i
].end_head
));
200 mbr
.entries
[i
].length
= grub_cpu_to_le32 (partition
->len
);
201 grub_free (partition
);
204 grub_memset (&(mbr
.entries
[i
]), 0, sizeof (mbr
.entries
[i
]));
206 /* The protective partition. */
207 if (first_sector
> 0xffffffff)
208 first_sector
= 0xffffffff;
211 mbr
.entries
[0].flag
= 0;
212 mbr
.entries
[0].type
= GRUB_PC_PARTITION_TYPE_GPT_DISK
;
213 mbr
.entries
[0].start
= grub_cpu_to_le32 (1);
215 &(mbr
.entries
[0].start_sector
),
216 &(mbr
.entries
[0].start_cylinder
),
217 &(mbr
.entries
[0].start_head
));
218 lba_to_chs (first_sector
,
219 &(mbr
.entries
[0].end_sector
),
220 &(mbr
.entries
[0].end_cylinder
),
221 &(mbr
.entries
[0].end_head
));
222 mbr
.entries
[0].length
= grub_cpu_to_le32 (first_sector
);
224 mbr
.signature
= grub_cpu_to_le16 (GRUB_PC_PARTITION_SIGNATURE
);
226 if (grub_disk_write (dev
->disk
, 0, 0, sizeof (mbr
), &mbr
))
228 grub_device_close (dev
);
232 grub_printf ("New MBR is written to '%s'\n", args
[0]);
234 return GRUB_ERR_NONE
;
238 static grub_command_t cmd
;
240 GRUB_MOD_INIT(gptsync
)
242 (void) mod
; /* To stop warning. */
243 cmd
= grub_register_command ("gptsync", grub_cmd_gptsync
,
244 N_("DEVICE [PARTITION[+/-[TYPE]]] ..."),
245 N_("Fill hybrid MBR of GPT drive DEVICE. "
246 "Specified partitions will be a part "
247 "of hybrid MBR. Up to 3 partitions are "
248 "allowed. TYPE is an MBR type. "
249 "+ means that partition is active. "
250 "Only one partition can be active."));
253 GRUB_MOD_FINI(gptsync
)
255 grub_unregister_command (cmd
);