diff options
Diffstat (limited to 'grub-core/partmap/acorn.c')
| -rw-r--r-- | grub-core/partmap/acorn.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/grub-core/partmap/acorn.c b/grub-core/partmap/acorn.c new file mode 100644 index 0000000..c022c61 --- /dev/null +++ b/grub-core/partmap/acorn.c @@ -0,0 +1,154 @@ +/* acorn.c - Read Linux/ADFS partition tables. */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2005,2007 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/disk.h> +#include <grub/misc.h> +#include <grub/mm.h> +#include <grub/partition.h> +#include <grub/acorn_filecore.h> + +GRUB_MOD_LICENSE ("GPLv3+"); + +#define LINUX_NATIVE_MAGIC grub_cpu_to_le32_compile_time (0xdeafa1de) +#define LINUX_SWAP_MAGIC grub_cpu_to_le32_compile_time (0xdeafab1e) +#define LINUX_MAP_ENTRIES (512 / 12) + +#define NONADFS_PARTITION_TYPE_LINUX 9 +#define NONADFS_PARTITION_TYPE_MASK 15 + +struct grub_acorn_boot_block +{ + union + { + struct + { + grub_uint8_t misc[0x1C0]; + struct grub_filecore_disc_record disc_record; + grub_uint8_t flags; + grub_uint16_t start_cylinder; + grub_uint8_t checksum; + } GRUB_PACKED; + grub_uint8_t bin[0x200]; + }; +} GRUB_PACKED; + +struct linux_part +{ + grub_uint32_t magic; + grub_uint32_t start; + grub_uint32_t size; +}; + +static struct grub_partition_map grub_acorn_partition_map; + +static grub_err_t +acorn_partition_map_find (grub_disk_t disk, struct linux_part *m, + grub_disk_addr_t *sector) +{ + struct grub_acorn_boot_block boot; + grub_err_t err; + unsigned int checksum = 0; + unsigned int heads; + unsigned int sectors_per_cylinder; + int i; + + err = grub_disk_read (disk, 0xC00 / GRUB_DISK_SECTOR_SIZE, 0, + sizeof (struct grub_acorn_boot_block), + &boot); + if (err) + return err; + + if ((boot.flags & NONADFS_PARTITION_TYPE_MASK) != NONADFS_PARTITION_TYPE_LINUX) + goto fail; + + for (i = 0; i != 0x1ff; ++i) + checksum = ((checksum & 0xff) + (checksum >> 8) + boot.bin[i]); + + if ((grub_uint8_t) checksum != boot.checksum) + goto fail; + + heads = (boot.disc_record.heads + + ((boot.disc_record.lowsector >> 6) & 1)); + sectors_per_cylinder = boot.disc_record.secspertrack * heads; + *sector = grub_le_to_cpu16 (boot.start_cylinder) * sectors_per_cylinder; + + return grub_disk_read (disk, *sector, 0, + sizeof (struct linux_part) * LINUX_MAP_ENTRIES, + m); + +fail: + return grub_error (GRUB_ERR_BAD_PART_TABLE, + "Linux/ADFS partition map not found"); + +} + + +static grub_err_t +acorn_partition_map_iterate (grub_disk_t disk, + grub_partition_iterate_hook_t hook, + void *hook_data) +{ + struct grub_partition part; + struct linux_part map[LINUX_MAP_ENTRIES]; + int i; + grub_disk_addr_t sector = 0; + grub_err_t err; + + err = acorn_partition_map_find (disk, map, §or); + if (err) + return err; + + part.partmap = &grub_acorn_partition_map; + + for (i = 0; i != LINUX_MAP_ENTRIES; ++i) + { + if (map[i].magic != LINUX_NATIVE_MAGIC + && map[i].magic != LINUX_SWAP_MAGIC) + return GRUB_ERR_NONE; + + part.start = sector + map[i].start; + part.len = map[i].size; + part.offset = 6; + part.number = part.index = i; + + if (hook (disk, &part, hook_data)) + return grub_errno; + } + + return GRUB_ERR_NONE; +} + + + +/* Partition map type. */ +static struct grub_partition_map grub_acorn_partition_map = +{ + .name = "acorn", + .iterate = acorn_partition_map_iterate, +}; + +GRUB_MOD_INIT(part_acorn) +{ + grub_partition_map_register (&grub_acorn_partition_map); +} + +GRUB_MOD_FINI(part_acorn) +{ + grub_partition_map_unregister (&grub_acorn_partition_map); +} |