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/* acorn.c - Read Linux/ADFS partition tables. */
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* GRUB -- GRand Unified Bootloader
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* Copyright (C) 2005,2007 Free Software Foundation, Inc.
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* GRUB is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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* GRUB is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
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#include <grub/disk.h>
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#include <grub/misc.h>
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#include <grub/partition.h>
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#include <grub/acorn_filecore.h>
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#define LINUX_NATIVE_MAGIC grub_cpu_to_le32 (0xdeafa1de)
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#define LINUX_SWAP_MAGIC grub_cpu_to_le32 (0xdeafab1e)
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#define LINUX_MAP_ENTRIES (512 / 12)
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#define NONADFS_PARTITION_TYPE_LINUX 9
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#define NONADFS_PARTITION_TYPE_MASK 15
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struct grub_acorn_boot_block
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grub_uint8_t misc[0x1C0];
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struct grub_filecore_disc_record disc_record;
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grub_uint16_t start_cylinder;
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grub_uint8_t checksum;
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} __attribute__ ((packed, aligned));
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static struct grub_partition_map grub_acorn_partition_map;
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acorn_partition_map_find (grub_disk_t disk, struct linux_part *m,
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grub_disk_addr_t *sector)
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struct grub_acorn_boot_block boot;
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unsigned int checksum = 0;
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unsigned int sectors_per_cylinder;
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err = grub_disk_read (disk, 0xC00 / GRUB_DISK_SECTOR_SIZE, 0,
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sizeof (struct grub_acorn_boot_block),
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if ((boot.flags & NONADFS_PARTITION_TYPE_MASK) != NONADFS_PARTITION_TYPE_LINUX)
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for (i = 0; i != 0x1ff; ++i)
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checksum = (checksum & 0xff) + (checksum >> 8) + boot.misc[i];
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if ((grub_uint8_t) checksum != boot.checksum)
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heads = (boot.disc_record.heads
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+ ((boot.disc_record.lowsector >> 6) & 1));
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sectors_per_cylinder = boot.disc_record.secspertrack * heads;
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*sector = grub_le_to_cpu16 (boot.start_cylinder) * sectors_per_cylinder;
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return grub_disk_read (disk, *sector, 0,
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sizeof (struct linux_part) * LINUX_MAP_ENTRIES,
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return grub_error (GRUB_ERR_BAD_PART_TABLE,
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"Linux/ADFS partition map not found");
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acorn_partition_map_iterate (grub_disk_t disk,
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int (*hook) (grub_disk_t disk,
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const grub_partition_t partition))
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struct grub_partition part;
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struct linux_part map[LINUX_MAP_ENTRIES];
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grub_disk_addr_t sector = 0;
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err = acorn_partition_map_find (disk, map, §or);
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part.partmap = &grub_acorn_partition_map;
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for (i = 0; i != LINUX_MAP_ENTRIES; ++i)
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if (map[i].magic != LINUX_NATIVE_MAGIC
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&& map[i].magic != LINUX_SWAP_MAGIC)
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return GRUB_ERR_NONE;
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part.start = sector + map[i].start;
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part.len = map[i].size;
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part.number = part.index = i;
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if (hook (disk, &part))
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return GRUB_ERR_NONE;
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/* Partition map type. */
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static struct grub_partition_map grub_acorn_partition_map =
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.iterate = acorn_partition_map_iterate,
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GRUB_MOD_INIT(part_acorn)
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grub_partition_map_register (&grub_acorn_partition_map);
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GRUB_MOD_FINI(part_acorn)
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grub_partition_map_unregister (&grub_acorn_partition_map);