git.oblomov.eu Git - linux-2.6/blob - 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
  26 static 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
  33 int atari_partition(struct parsed_partitions *state, struct block_device *bdev)
  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 = (struct rootsector *) read_dev_sector(bdev, 0, &sect);
  46         if (!rs)
  47                 return -1;
  48
  49         /* Verify this is an Atari rootsector: */
  50         hd_size = 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         printk (" AHDI");
  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                 printk(" XGM<");
  85                 partsect = extensect = be32_to_cpu(pi->st);
  86                 while (1) {
  87                         xrs = (struct rootsector *)read_dev_sector(bdev, partsect, &sect2);
  88                         if (!xrs) {
  89                                 printk (" block %ld read failed\n", partsect);
  90                                 put_dev_sector(sect);
  91                                 return 0;
  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                 printk(" >");
 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                         printk(" ICD<");
 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                         printk(" >");
 141                 }
 142         }
 143 #endif
 144         put_dev_sector(sect);
 145
 146         printk ("\n");
 147
 148         return 1;
 149 }