LXR linux/block/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        /*
  46         * ATARI partition scheme supports 512 lba only.  If this is not
  47         * the case, bail early to avoid miscalculating hd_size.
  48         */
  49        if (bdev_logical_block_size(state->bdev) != 512)
  50                return 0;
  51
  52        rs = read_part_sector(state, 0, &sect);
  53        if (!rs)
  54                return -1;
  55
  56        /* Verify this is an Atari rootsector: */
  57        hd_size = state->bdev->bd_inode->i_size >> 9;
  58        if (!VALID_PARTITION(&rs->part[0], hd_size) &&
  59            !VALID_PARTITION(&rs->part[1], hd_size) &&
  60            !VALID_PARTITION(&rs->part[2], hd_size) &&
  61            !VALID_PARTITION(&rs->part[3], hd_size)) {
  62                /*
  63                 * if there's no valid primary partition, assume that no Atari
  64                 * format partition table (there's no reliable magic or the like
  65                 * :-()
  66                 */
  67                put_dev_sector(sect);
  68                return 0;
  69        }
  70
  71        pi = &rs->part[0];
  72        strlcat(state->pp_buf, " AHDI", PAGE_SIZE);
  73        for (slot = 1; pi < &rs->part[4] && slot < state->limit; slot++, pi++) {
  74                struct rootsector *xrs;
  75                Sector sect2;
  76                ulong partsect;
  77
  78                if ( !(pi->flg & 1) )
  79                        continue;
  80                /* active partition */
  81                if (memcmp (pi->id, "XGM", 3) != 0) {
  82                        /* we don't care about other id's */
  83                        put_partition (state, slot, be32_to_cpu(pi->st),
  84                                        be32_to_cpu(pi->siz));
  85                        continue;
  86                }
  87                /* extension partition */
  88#ifdef ICD_PARTS
  89                part_fmt = 1;
  90#endif
  91                strlcat(state->pp_buf, " XGM<", PAGE_SIZE);
  92                partsect = extensect = be32_to_cpu(pi->st);
  93                while (1) {
  94                        xrs = read_part_sector(state, partsect, &sect2);
  95                        if (!xrs) {
  96                                printk (" block %ld read failed\n", partsect);
  97                                put_dev_sector(sect);
  98                                return -1;
  99                        }
 100
 101                        /* ++roman: sanity check: bit 0 of flg field must be set */
 102                        if (!(xrs->part[0].flg & 1)) {
 103                                printk( "\nFirst sub-partition in extended partition is not valid!\n" );
 104                                put_dev_sector(sect2);
 105                                break;
 106                        }
 107
 108                        put_partition(state, slot,
 109                                   partsect + be32_to_cpu(xrs->part[0].st),
 110                                   be32_to_cpu(xrs->part[0].siz));
 111
 112                        if (!(xrs->part[1].flg & 1)) {
 113                                /* end of linked partition list */
 114                                put_dev_sector(sect2);
 115                                break;
 116                        }
 117                        if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
 118                                printk("\nID of extended partition is not XGM!\n");
 119                                put_dev_sector(sect2);
 120                                break;
 121                        }
 122
 123                        partsect = be32_to_cpu(xrs->part[1].st) + extensect;
 124                        put_dev_sector(sect2);
 125                        if (++slot == state->limit) {
 126                                printk( "\nMaximum number of partitions reached!\n" );
 127                                break;
 128                        }
 129                }
 130                strlcat(state->pp_buf, " >", PAGE_SIZE);
 131        }
 132#ifdef ICD_PARTS
 133        if ( part_fmt!=1 ) { /* no extended partitions -> test ICD-format */
 134                pi = &rs->icdpart[0];
 135                /* sanity check: no ICD format if first partition invalid */
 136                if (OK_id(pi->id)) {
 137                        strlcat(state->pp_buf, " ICD<", PAGE_SIZE);
 138                        for (; pi < &rs->icdpart[8] && slot < state->limit; slot++, pi++) {
 139                                /* accept only GEM,BGM,RAW,LNX,SWP partitions */
 140                                if (!((pi->flg & 1) && OK_id(pi->id)))
 141                                        continue;
 142                                part_fmt = 2;
 143                                put_partition (state, slot,
 144                                                be32_to_cpu(pi->st),
 145                                                be32_to_cpu(pi->siz));
 146                        }
 147                        strlcat(state->pp_buf, " >", PAGE_SIZE);
 148                }
 149        }
 150#endif
 151        put_dev_sector(sect);
 152
 153        strlcat(state->pp_buf, "\n", PAGE_SIZE);
 154
 155        return 1;
 156}
 157