xref: /linux/block/partitions/ultrix.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  *  fs/partitions/ultrix.c
3  *
4  *  Code extracted from drivers/block/genhd.c
5  *
6  *  Re-organised Jul 1999 Russell King
7  */
8 
9 #include "check.h"
10 #include "ultrix.h"
11 
12 int ultrix_partition(struct parsed_partitions *state)
13 {
14 	int i;
15 	Sector sect;
16 	unsigned char *data;
17 	struct ultrix_disklabel {
18 		s32	pt_magic;	/* magic no. indicating part. info exits */
19 		s32	pt_valid;	/* set by driver if pt is current */
20 		struct  pt_info {
21 			s32		pi_nblocks; /* no. of sectors */
22 			u32		pi_blkoff;  /* block offset for start */
23 		} pt_part[8];
24 	} *label;
25 
26 #define PT_MAGIC	0x032957	/* Partition magic number */
27 #define PT_VALID	1		/* Indicates if struct is valid */
28 
29 	data = read_part_sector(state, (16384 - sizeof(*label))/512, &sect);
30 	if (!data)
31 		return -1;
32 
33 	label = (struct ultrix_disklabel *)(data + 512 - sizeof(*label));
34 
35 	if (label->pt_magic == PT_MAGIC && label->pt_valid == PT_VALID) {
36 		for (i=0; i<8; i++)
37 			if (label->pt_part[i].pi_nblocks)
38 				put_partition(state, i+1,
39 					      label->pt_part[i].pi_blkoff,
40 					      label->pt_part[i].pi_nblocks);
41 		put_dev_sector(sect);
42 		strlcat(state->pp_buf, "\n", PAGE_SIZE);
43 		return 1;
44 	} else {
45 		put_dev_sector(sect);
46 		return 0;
47 	}
48 }
49