fs/partitions/ultrix.c

   1 /*
   2  *  fs/partitions/ultrix.c
   3  *
   4  *  Code extracted from drivers/block/genhd.c
   5  *
   6  *  Re-organised Jul 1999 Russell King
   7  */
   8
   9 #include "check.h"
  10 #include "ultrix.h"
  11
  12 int ultrix_partition(struct parsed_partitions *state, struct block_device *bdev)
  13 {
  14         int i;
  15         Sector sect;
  16         unsigned char *data;
  17         struct ultrix_disklabel {
  18                 s32     pt_magic;       /* magic no. indicating part. info exits */
  19                 s32     pt_valid;       /* set by driver if pt is current */
  20                 struct  pt_info {
  21                         s32             pi_nblocks; /* no. of sectors */
  22                         u32             pi_blkoff;  /* block offset for start */
  23                 } pt_part[8];
  24         } *label;
  25
  26 #define PT_MAGIC        0x032957        /* Partition magic number */
  27 #define PT_VALID        1               /* Indicates if struct is valid */
  28
  29         data = read_dev_sector(bdev, (16384 - sizeof(*label))/512, &sect);
  30         if (!data)
  31                 return -1;
  32
  33         label = (struct ultrix_disklabel *)(data + 512 - sizeof(*label));
  34
  35         if (label->pt_magic == PT_MAGIC && label->pt_valid == PT_VALID) {
  36                 for (i=0; i<8; i++)
  37                         if (label->pt_part[i].pi_nblocks)
  38                                 put_partition(state, i+1,
  39                                               label->pt_part[i].pi_blkoff,
  40                                               label->pt_part[i].pi_nblocks);
  41                 put_dev_sector(sect);
  42                 printk ("\n");
  43                 return 1;
  44         } else {
  45                 put_dev_sector(sect);
  46                 return 0;
  47         }
  48 }