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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/config.h>

#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"

#ifdef CONFIG_BLK_DEV_MD

extern void md_autodetect_dev(kdev_t dev);

#endif

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 spare0[14];

                struct sun_info {

                        unsigned char spare1;

                        unsigned char id;

                        unsigned char spare2;

                        unsigned char flags;

                } infos[8];

                unsigned char spare[246];  /* 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, &sect);

        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);

#ifdef CONFIG_BLK_DEV_MD

                        if (label->infos[i].id == LINUX_RAID_PARTITION)

                                md_autodetect_dev(MKDEV(hd->major,

                                                        first_part_minor));

#endif

                }

                first_part_minor++;

        }

        printk("\n");

        put_dev_sector(sect);

        return 1;

}