i386/linux-2.3.21/fs/partitions/osf.c

   1 /*
   2  *  fs/partitions/osf.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/fs.h>
  11 #include <linux/genhd.h>
  12 #include <linux/kernel.h>
  13 #include <linux/major.h>
  14 #include <linux/string.h>
  15 #include <linux/blk.h>
  16
  17 #include "check.h"
  18 #include "osf.h"
  19
  20 int osf_partition(struct gendisk *hd, kdev_t dev, unsigned long first_sector,
  21                   int current_minor)
  22 {
  23         int i;
  24         int mask = (1 << hd->minor_shift) - 1;
  25         struct buffer_head *bh;
  26         struct disklabel {
  27                 u32 d_magic;
  28                 u16 d_type,d_subtype;
  29                 u8 d_typename[16];
  30                 u8 d_packname[16];
  31                 u32 d_secsize;
  32                 u32 d_nsectors;
  33                 u32 d_ntracks;
  34                 u32 d_ncylinders;
  35                 u32 d_secpercyl;
  36                 u32 d_secprtunit;
  37                 u16 d_sparespertrack;
  38                 u16 d_sparespercyl;
  39                 u32 d_acylinders;
  40                 u16 d_rpm, d_interleave, d_trackskew, d_cylskew;
  41                 u32 d_headswitch, d_trkseek, d_flags;
  42                 u32 d_drivedata[5];
  43                 u32 d_spare[5];
  44                 u32 d_magic2;
  45                 u16 d_checksum;
  46                 u16 d_npartitions;
  47                 u32 d_bbsize, d_sbsize;
  48                 struct d_partition {
  49                         u32 p_size;
  50                         u32 p_offset;
  51                         u32 p_fsize;
  52                         u8  p_fstype;
  53                         u8  p_frag;
  54                         u16 p_cpg;
  55                 } d_partitions[8];
  56         } * label;
  57         struct d_partition * partition;
  58
  59         if (!(bh = bread(dev,0,get_ptable_blocksize(dev)))) {
  60                 printk("unable to read partition table\n");
  61                 return -1;
  62         }
  63         label = (struct disklabel *) (bh->b_data+64);
  64         partition = label->d_partitions;
  65         if (label->d_magic != DISKLABELMAGIC) {
  66                 brelse(bh);
  67                 return 0;
  68         }
  69         if (label->d_magic2 != DISKLABELMAGIC) {
  70                 brelse(bh);
  71                 return 0;
  72         }
  73         for (i = 0 ; i < label->d_npartitions; i++, partition++) {
  74                 if ((current_minor & mask) == 0)
  75                         break;
  76                 if (partition->p_size)
  77                         add_gd_partition(hd, current_minor,
  78                                 first_sector+partition->p_offset,
  79                                 partition->p_size);
  80                 current_minor++;
  81         }
  82         printk("\n");
  83         brelse(bh);
  84         return 1;
  85 }
  86