LXR linux/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
  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 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
 137rdb_done:
 138        return res;
 139}
 140