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/*
* fs/partitions/sun.c
*
* Code extracted from drivers/block/genhd.c
*
* Copyright (C) 1991-1998 Linus Torvalds
* Re-organised Feb 1998 Russell King
*/
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/blk.h>
#include <asm/system.h>
#include "check.h"
#include "sun.h"
int sun_partition(struct gendisk *hd, struct block_device *bdev, unsigned long first_sector, int first_part_minor)
{
int i, csum;
unsigned short *ush;
Sector sect;
kdev_t dev = to_kdev_t(bdev->bd_dev);
struct sun_disklabel {
unsigned char info[128]; /* Informative text string */
unsigned char spare[292]; /* Boot information etc. */
unsigned short rspeed; /* Disk rotational speed */
unsigned short pcylcount; /* Physical cylinder count */
unsigned short sparecyl; /* extra sects per cylinder */
unsigned char spare2[4]; /* More magic... */
unsigned short ilfact; /* Interleave factor */
unsigned short ncyl; /* Data cylinder count */
unsigned short nacyl; /* Alt. cylinder count */
unsigned short ntrks; /* Tracks per cylinder */
unsigned short nsect; /* Sectors per track */
unsigned char spare3[4]; /* Even more magic... */
struct sun_partition {
__u32 start_cylinder;
__u32 num_sectors;
} partitions[8];
unsigned short magic; /* Magic number */
unsigned short csum; /* Label xor'd checksum */
} * label;
struct sun_partition *p;
unsigned long spc;
label = (struct sun_disklabel *)read_dev_sector(bdev, 0, §);
if (!label)
return -1;
p = label->partitions;
if (be16_to_cpu(label->magic) != SUN_LABEL_MAGIC) {
/* printk(KERN_INFO "Dev %s Sun disklabel: bad magic %04x\n",
bdevname(dev), be16_to_cpu(label->magic)); */
put_dev_sector(sect);
return 0;
}
/* Look at the checksum */
ush = ((unsigned short *) (label+1)) - 1;
for (csum = 0; ush >= ((unsigned short *) label);)
csum ^= *ush--;
if(csum) {
printk("Dev %s Sun disklabel: Csum bad, label corrupted\n",
bdevname(dev));
put_dev_sector(sect);
return 0;
}
/* All Sun disks have 8 partition entries */
spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
for(i=0; i < 8; i++, p++) {
unsigned long st_sector;
int num_sectors;
st_sector = first_sector + be32_to_cpu(p->start_cylinder) * spc;
num_sectors = be32_to_cpu(p->num_sectors);
if (num_sectors)
add_gd_partition(hd, first_part_minor, st_sector, num_sectors);
first_part_minor++;
}
printk("\n");
put_dev_sector(sect);
return 1;
}
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