block/partitions/amiga.c

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