LXR linux/block/partitions/amiga.c

   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
  18static __inline__ u32
  19checksum_block(__be32 *m, int size)
  20{
  21        u32 sum = 0;
  22
  23        while (size--)
  24                sum += be32_to_cpu(*m++);
  25        return sum;
  26}
  27
  28int amiga_partition(struct parsed_partitions *state)
  29{
  30        Sector sect;
  31        unsigned char *data;
  32        struct RigidDiskBlock *rdb;
  33        struct PartitionBlock *pb;
  34        int start_sect, nr_sects, blk, part, res = 0;
  35        int blksize = 1;        /* Multiplier for disk block size */
  36        int slot = 1;
  37
  38        for (blk = 0; ; blk++, put_dev_sector(sect)) {
  39                if (blk == RDB_ALLOCATION_LIMIT)
  40                        goto rdb_done;
  41                data = read_part_sector(state, blk, &sect);
  42                if (!data) {
  43                        pr_err("Dev %s: unable to read RDB block %d\n",
  44                               state->disk->disk_name, 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                        pr_err("Trashed word at 0xd0 in block %d ignored in checksum calculation\n",
  61                               blk);
  62                        break;
  63                }
  64
  65                pr_err("Dev %s: RDB in block %d has bad checksum\n",
  66                       state->disk->disk_name, 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                        pr_err("Dev %s: unable to read partition block %d\n",
  86                               state->disk->disk_name, blk);
  87                        res = -1;
  88                        goto rdb_done;
  89                }
  90                pb  = (struct PartitionBlock *)data;
  91                blk = be32_to_cpu(pb->pb_Next);
  92                if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION))
  93                        continue;
  94                if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 )
  95                        continue;
  96
  97                /* Tell Kernel about it */
  98
  99                nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
 100                            be32_to_cpu(pb->pb_Environment[9])) *
 101                           be32_to_cpu(pb->pb_Environment[3]) *
 102                           be32_to_cpu(pb->pb_Environment[5]) *
 103                           blksize;
 104                if (!nr_sects)
 105                        continue;
 106                start_sect = be32_to_cpu(pb->pb_Environment[9]) *
 107                             be32_to_cpu(pb->pb_Environment[3]) *
 108                             be32_to_cpu(pb->pb_Environment[5]) *
 109                             blksize;
 110                put_partition(state,slot++,start_sect,nr_sects);
 111                {
 112                        /* Be even more informative to aid mounting */
 113                        char dostype[4];
 114                        char tmp[42];
 115
 116                        __be32 *dt = (__be32 *)dostype;
 117                        *dt = pb->pb_Environment[16];
 118                        if (dostype[3] < ' ')
 119                                snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)",
 120                                        dostype[0], dostype[1],
 121                                        dostype[2], dostype[3] + '@' );
 122                        else
 123                                snprintf(tmp, sizeof(tmp), " (%c%c%c%c)",
 124                                        dostype[0], dostype[1],
 125                                        dostype[2], dostype[3]);
 126                        strlcat(state->pp_buf, tmp, PAGE_SIZE);
 127                        snprintf(tmp, sizeof(tmp), "(res %d spb %d)",
 128                                be32_to_cpu(pb->pb_Environment[6]),
 129                                be32_to_cpu(pb->pb_Environment[4]));
 130                        strlcat(state->pp_buf, tmp, PAGE_SIZE);
 131                }
 132                res = 1;
 133        }
 134        strlcat(state->pp_buf, "\n", PAGE_SIZE);
 135
 136rdb_done:
 137        return res;
 138}
 139