1/* 2 * fs/partitions/amiga.c 3 * 4 * Code extracted from drivers/block/genhd.c 5 * 6 * Copyright (C) 1991-1998 Linus Torvalds 7 * Re-organised Feb 1998 Russell King 8 */ 9 10#include <linux/types.h> 11#include <linux/affs_hardblocks.h> 12 13#include "check.h" 14#include "amiga.h" 15 16static __inline__ u32 17checksum_block(__be32 *m, int size) 18{ 19 u32 sum = 0; 20 21 while (size--) 22 sum += be32_to_cpu(*m++); 23 return sum; 24} 25 26int 27amiga_partition(struct parsed_partitions *state, struct block_device *bdev) 28{ 29 Sector sect; 30 unsigned char *data; 31 struct RigidDiskBlock *rdb; 32 struct PartitionBlock *pb; 33 int start_sect, nr_sects, blk, part, res = 0; 34 int blksize = 1; /* Multiplier for disk block size */ 35 int slot = 1; 36 char b[BDEVNAME_SIZE]; 37 38 for (blk = 0; ; blk++, put_dev_sector(sect)) { 39 if (blk == RDB_ALLOCATION_LIMIT) 40 goto rdb_done; 41 data = read_dev_sector(bdev, blk, §); 42 if (!data) { 43 if (warn_no_part) 44 printk("Dev %s: unable to read RDB block %d\n", 45 bdevname(bdev, b), blk); 46 res = -1; 47 goto rdb_done; 48 } 49 if (*(__be32 *)data != cpu_to_be32(IDNAME_RIGIDDISK)) 50 continue; 51 52 rdb = (struct RigidDiskBlock *)data; 53 if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F) == 0) 54 break; 55 /* Try again with 0xdc..0xdf zeroed, Windows might have 56 * trashed it. 57 */ 58 *(__be32 *)(data+0xdc) = 0; 59 if (checksum_block((__be32 *)data, 60 be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) { 61 printk("Warning: Trashed word at 0xd0 in block %d " 62 "ignored in checksum calculation\n",blk); 63 break; 64 } 65 66 printk("Dev %s: RDB in block %d has bad checksum\n", 67 bdevname(bdev, b), blk); 68 } 69 70 /* blksize is blocks per 512 byte standard block */ 71 blksize = be32_to_cpu( rdb->rdb_BlockBytes ) / 512; 72 73 printk(" RDSK (%d)", blksize * 512); /* Be more informative */ 74 blk = be32_to_cpu(rdb->rdb_PartitionList); 75 put_dev_sector(sect); 76 for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) { 77 blk *= blksize; /* Read in terms partition table understands */ 78 data = read_dev_sector(bdev, blk, §); 79 if (!data) { 80 if (warn_no_part) 81 printk("Dev %s: unable to read partition block %d\n", 82 bdevname(bdev, b), blk); 83 res = -1; 84 goto rdb_done; 85 } 86 pb = (struct PartitionBlock *)data; 87 blk = be32_to_cpu(pb->pb_Next); 88 if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION)) 89 continue; 90 if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 ) 91 continue; 92 93 /* Tell Kernel about it */ 94 95 nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 - 96 be32_to_cpu(pb->pb_Environment[9])) * 97 be32_to_cpu(pb->pb_Environment[3]) * 98 be32_to_cpu(pb->pb_Environment[5]) * 99 blksize; 100 if (!nr_sects) 101 continue; 102 start_sect = be32_to_cpu(pb->pb_Environment[9]) * 103 be32_to_cpu(pb->pb_Environment[3]) * 104 be32_to_cpu(pb->pb_Environment[5]) * 105 blksize; 106 put_partition(state,slot++,start_sect,nr_sects); 107 { 108 /* Be even more informative to aid mounting */ 109 char dostype[4]; 110 __be32 *dt = (__be32 *)dostype; 111 *dt = pb->pb_Environment[16]; 112 if (dostype[3] < ' ') 113 printk(" (%c%c%c^%c)", 114 dostype[0], dostype[1], 115 dostype[2], dostype[3] + '@' ); 116 else 117 printk(" (%c%c%c%c)", 118 dostype[0], dostype[1], 119 dostype[2], dostype[3]); 120 printk("(res %d spb %d)", 121 be32_to_cpu(pb->pb_Environment[6]), 122 be32_to_cpu(pb->pb_Environment[4])); 123 } 124 res = 1; 125 } 126 printk("\n"); 127 128rdb_done: 129 return res; 130} 131