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#include "amiga.h"
  18
  19static __inline__ u32
  20checksum_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
  29int 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, &sect);
  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, &sect);
  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
 140rdb_done:
 141        return res;
 142}
 143