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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, kdev_t dev, unsigned long first_sector, int first_part_minor) { int i, csum; unsigned short *ush; struct buffer_head *bh; 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; if(!(bh = bread(dev, 0, get_ptable_blocksize(dev)))) { if (warn_no_part) printk(KERN_WARNING "Dev %s: unable to read partition table\n", kdevname(dev)); return -1; } label = (struct sun_disklabel *) bh->b_data; p = label->partitions; if (be16_to_cpu(label->magic) != SUN_LABEL_MAGIC) { /* printk(KERN_INFO "Dev %s Sun disklabel: bad magic %04x\n", kdevname(dev), be16_to_cpu(label->magic)); */ brelse(bh); 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", kdevname(dev)); brelse(bh); 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"); brelse(bh); return 1; } |