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/*
* fs/partitions/sgi.c
*
* Code extracted from drivers/block/genhd.c
*/
#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/byteorder.h>
#include <asm/system.h>
#include "check.h"
#include "sgi.h"
int sgi_partition(struct gendisk *hd, struct block_device *bdev, unsigned long first_sector, int current_minor)
{
int i, csum, magic;
unsigned int *ui, start, blocks, cs;
Sector sect;
kdev_t dev = to_kdev_t(bdev->bd_dev);
struct sgi_disklabel {
int magic_mushroom; /* Big fat spliff... */
short root_part_num; /* Root partition number */
short swap_part_num; /* Swap partition number */
char boot_file[16]; /* Name of boot file for ARCS */
unsigned char _unused0[48]; /* Device parameter useless crapola.. */
struct sgi_volume {
char name[8]; /* Name of volume */
int block_num; /* Logical block number */
int num_bytes; /* How big, in bytes */
} volume[15];
struct sgi_partition {
int num_blocks; /* Size in logical blocks */
int first_block; /* First logical block */
int type; /* Type of this partition */
} partitions[16];
int csum; /* Disk label checksum */
int _unused1; /* Padding */
} *label;
struct sgi_partition *p;
label = (struct sgi_disklabel *) read_dev_sector(bdev, 0, §);
if (!label)
return -1;
p = &label->partitions[0];
magic = label->magic_mushroom;
if(be32_to_cpu(magic) != SGI_LABEL_MAGIC) {
/*printk("Dev %s SGI disklabel: bad magic %08x\n",
bdevname(dev), magic);*/
put_dev_sector(sect);
return 0;
}
ui = ((unsigned int *) (label + 1)) - 1;
for(csum = 0; ui >= ((unsigned int *) label);) {
cs = *ui--;
csum += be32_to_cpu(cs);
}
if(csum) {
printk(KERN_WARNING "Dev %s SGI disklabel: csum bad, label corrupted\n",
bdevname(dev));
put_dev_sector(sect);
return 0;
}
/* All SGI disk labels have 16 partitions, disks under Linux only
* have 15 minor's. Luckily there are always a few zero length
* partitions which we don't care about so we never overflow the
* current_minor.
*/
for(i = 0; i < 16; i++, p++) {
blocks = be32_to_cpu(p->num_blocks);
start = be32_to_cpu(p->first_block);
if(!blocks)
continue;
add_gd_partition(hd, current_minor, start, blocks);
current_minor++;
}
printk("\n");
put_dev_sector(sect);
return 1;
}
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