LXR linux/fs/partitions/atari.c

   1/*
   2 *  fs/partitions/atari.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/ctype.h>
  11#include "check.h"
  12#include "atari.h"
  13
  14/* ++guenther: this should be settable by the user ("make config")?.
  15 */
  16#define ICD_PARTS
  17
  18/* check if a partition entry looks valid -- Atari format is assumed if at
  19   least one of the primary entries is ok this way */
  20#define VALID_PARTITION(pi,hdsiz)                                            \
  21    (((pi)->flg & 1) &&                                                      \
  22     isalnum((pi)->id[0]) && isalnum((pi)->id[1]) && isalnum((pi)->id[2]) && \
  23     be32_to_cpu((pi)->st) <= (hdsiz) &&                                     \
  24     be32_to_cpu((pi)->st) + be32_to_cpu((pi)->siz) <= (hdsiz))
  25
  26static inline int OK_id(char *s)
  27{
  28        return  memcmp (s, "GEM", 3) == 0 || memcmp (s, "BGM", 3) == 0 ||
  29                memcmp (s, "LNX", 3) == 0 || memcmp (s, "SWP", 3) == 0 ||
  30                memcmp (s, "RAW", 3) == 0 ;
  31}
  32
  33int atari_partition(struct parsed_partitions *state)
  34{
  35        Sector sect;
  36        struct rootsector *rs;
  37        struct partition_info *pi;
  38        u32 extensect;
  39        u32 hd_size;
  40        int slot;
  41#ifdef ICD_PARTS
  42        int part_fmt = 0; /* 0:unknown, 1:AHDI, 2:ICD/Supra */
  43#endif
  44
  45        rs = read_part_sector(state, 0, &sect);
  46        if (!rs)
  47                return -1;
  48
  49        /* Verify this is an Atari rootsector: */
  50        hd_size = state->bdev->bd_inode->i_size >> 9;
  51        if (!VALID_PARTITION(&rs->part[0], hd_size) &&
  52            !VALID_PARTITION(&rs->part[1], hd_size) &&
  53            !VALID_PARTITION(&rs->part[2], hd_size) &&
  54            !VALID_PARTITION(&rs->part[3], hd_size)) {
  55                /*
  56                 * if there's no valid primary partition, assume that no Atari
  57                 * format partition table (there's no reliable magic or the like
  58                 * :-()
  59                 */
  60                put_dev_sector(sect);
  61                return 0;
  62        }
  63
  64        pi = &rs->part[0];
  65        strlcat(state->pp_buf, " AHDI", PAGE_SIZE);
  66        for (slot = 1; pi < &rs->part[4] && slot < state->limit; slot++, pi++) {
  67                struct rootsector *xrs;
  68                Sector sect2;
  69                ulong partsect;
  70
  71                if ( !(pi->flg & 1) )
  72                        continue;
  73                /* active partition */
  74                if (memcmp (pi->id, "XGM", 3) != 0) {
  75                        /* we don't care about other id's */
  76                        put_partition (state, slot, be32_to_cpu(pi->st),
  77                                        be32_to_cpu(pi->siz));
  78                        continue;
  79                }
  80                /* extension partition */
  81#ifdef ICD_PARTS
  82                part_fmt = 1;
  83#endif
  84                strlcat(state->pp_buf, " XGM<", PAGE_SIZE);
  85                partsect = extensect = be32_to_cpu(pi->st);
  86                while (1) {
  87                        xrs = read_part_sector(state, partsect, &sect2);
  88                        if (!xrs) {
  89                                printk (" block %ld read failed\n", partsect);
  90                                put_dev_sector(sect);
  91                                return -1;
  92                        }
  93
  94                        /* ++roman: sanity check: bit 0 of flg field must be set */
  95                        if (!(xrs->part[0].flg & 1)) {
  96                                printk( "\nFirst sub-partition in extended partition is not valid!\n" );
  97                                put_dev_sector(sect2);
  98                                break;
  99                        }
 100
 101                        put_partition(state, slot,
 102                                   partsect + be32_to_cpu(xrs->part[0].st),
 103                                   be32_to_cpu(xrs->part[0].siz));
 104
 105                        if (!(xrs->part[1].flg & 1)) {
 106                                /* end of linked partition list */
 107                                put_dev_sector(sect2);
 108                                break;
 109                        }
 110                        if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
 111                                printk("\nID of extended partition is not XGM!\n");
 112                                put_dev_sector(sect2);
 113                                break;
 114                        }
 115
 116                        partsect = be32_to_cpu(xrs->part[1].st) + extensect;
 117                        put_dev_sector(sect2);
 118                        if (++slot == state->limit) {
 119                                printk( "\nMaximum number of partitions reached!\n" );
 120                                break;
 121                        }
 122                }
 123                strlcat(state->pp_buf, " >", PAGE_SIZE);
 124        }
 125#ifdef ICD_PARTS
 126        if ( part_fmt!=1 ) { /* no extended partitions -> test ICD-format */
 127                pi = &rs->icdpart[0];
 128                /* sanity check: no ICD format if first partition invalid */
 129                if (OK_id(pi->id)) {
 130                        strlcat(state->pp_buf, " ICD<", PAGE_SIZE);
 131                        for (; pi < &rs->icdpart[8] && slot < state->limit; slot++, pi++) {
 132                                /* accept only GEM,BGM,RAW,LNX,SWP partitions */
 133                                if (!((pi->flg & 1) && OK_id(pi->id)))
 134                                        continue;
 135                                part_fmt = 2;
 136                                put_partition (state, slot,
 137                                                be32_to_cpu(pi->st),
 138                                                be32_to_cpu(pi->siz));
 139                        }
 140                        strlcat(state->pp_buf, " >", PAGE_SIZE);
 141                }
 142        }
 143#endif
 144        put_dev_sector(sect);
 145
 146        strlcat(state->pp_buf, "\n", PAGE_SIZE);
 147
 148        return 1;
 149}
 150