1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * fs/partitions/amiga.c 4 * 5 * Code extracted from drivers/block/genhd.c 6 * 7 * Copyright (C) 1991-1998 Linus Torvalds 8 * Re-organised Feb 1998 Russell King 9 */ 10 11 #define pr_fmt(fmt) fmt 12 13 #include <linux/types.h> 14 #include <linux/affs_hardblocks.h> 15 16 #include "check.h" 17 #include "amiga.h" 18 19 static __inline__ u32 20 checksum_block(__be32 *m, int size) 21 { 22 u32 sum = 0; 23 24 while (size--) 25 sum += be32_to_cpu(*m++); 26 return sum; 27 } 28 29 int amiga_partition(struct parsed_partitions *state) 30 { 31 Sector sect; 32 unsigned char *data; 33 struct RigidDiskBlock *rdb; 34 struct PartitionBlock *pb; 35 int start_sect, nr_sects, blk, part, res = 0; 36 int blksize = 1; /* Multiplier for disk block size */ 37 int slot = 1; 38 char b[BDEVNAME_SIZE]; 39 40 for (blk = 0; ; blk++, put_dev_sector(sect)) { 41 if (blk == RDB_ALLOCATION_LIMIT) 42 goto rdb_done; 43 data = read_part_sector(state, blk, §); 44 if (!data) { 45 if (warn_no_part) 46 pr_err("Dev %s: unable to read RDB block %d\n", 47 bdevname(state->bdev, b), blk); 48 res = -1; 49 goto rdb_done; 50 } 51 if (*(__be32 *)data != cpu_to_be32(IDNAME_RIGIDDISK)) 52 continue; 53 54 rdb = (struct RigidDiskBlock *)data; 55 if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F) == 0) 56 break; 57 /* Try again with 0xdc..0xdf zeroed, Windows might have 58 * trashed it. 59 */ 60 *(__be32 *)(data+0xdc) = 0; 61 if (checksum_block((__be32 *)data, 62 be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) { 63 pr_err("Trashed word at 0xd0 in block %d ignored in checksum calculation\n", 64 blk); 65 break; 66 } 67 68 pr_err("Dev %s: RDB in block %d has bad checksum\n", 69 bdevname(state->bdev, b), blk); 70 } 71 72 /* blksize is blocks per 512 byte standard block */ 73 blksize = be32_to_cpu( rdb->rdb_BlockBytes ) / 512; 74 75 { 76 char tmp[7 + 10 + 1 + 1]; 77 78 /* Be more informative */ 79 snprintf(tmp, sizeof(tmp), " RDSK (%d)", blksize * 512); 80 strlcat(state->pp_buf, tmp, PAGE_SIZE); 81 } 82 blk = be32_to_cpu(rdb->rdb_PartitionList); 83 put_dev_sector(sect); 84 for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) { 85 blk *= blksize; /* Read in terms partition table understands */ 86 data = read_part_sector(state, blk, §); 87 if (!data) { 88 if (warn_no_part) 89 pr_err("Dev %s: unable to read partition block %d\n", 90 bdevname(state->bdev, b), blk); 91 res = -1; 92 goto rdb_done; 93 } 94 pb = (struct PartitionBlock *)data; 95 blk = be32_to_cpu(pb->pb_Next); 96 if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION)) 97 continue; 98 if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 ) 99 continue; 100 101 /* Tell Kernel about it */ 102 103 nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 - 104 be32_to_cpu(pb->pb_Environment[9])) * 105 be32_to_cpu(pb->pb_Environment[3]) * 106 be32_to_cpu(pb->pb_Environment[5]) * 107 blksize; 108 if (!nr_sects) 109 continue; 110 start_sect = be32_to_cpu(pb->pb_Environment[9]) * 111 be32_to_cpu(pb->pb_Environment[3]) * 112 be32_to_cpu(pb->pb_Environment[5]) * 113 blksize; 114 put_partition(state,slot++,start_sect,nr_sects); 115 { 116 /* Be even more informative to aid mounting */ 117 char dostype[4]; 118 char tmp[42]; 119 120 __be32 *dt = (__be32 *)dostype; 121 *dt = pb->pb_Environment[16]; 122 if (dostype[3] < ' ') 123 snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)", 124 dostype[0], dostype[1], 125 dostype[2], dostype[3] + '@' ); 126 else 127 snprintf(tmp, sizeof(tmp), " (%c%c%c%c)", 128 dostype[0], dostype[1], 129 dostype[2], dostype[3]); 130 strlcat(state->pp_buf, tmp, PAGE_SIZE); 131 snprintf(tmp, sizeof(tmp), "(res %d spb %d)", 132 be32_to_cpu(pb->pb_Environment[6]), 133 be32_to_cpu(pb->pb_Environment[4])); 134 strlcat(state->pp_buf, tmp, PAGE_SIZE); 135 } 136 res = 1; 137 } 138 strlcat(state->pp_buf, "\n", PAGE_SIZE); 139 140 rdb_done: 141 return res; 142 } 143