xref: /openbmc/linux/block/partitions/sysv68.c (revision 550987be)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  fs/partitions/sysv68.c
4  *
5  *  Copyright (C) 2007 Philippe De Muyter <phdm@macqel.be>
6  */
7 
8 #include "check.h"
9 #include "sysv68.h"
10 
11 /*
12  *	Volume ID structure: on first 256-bytes sector of disk
13  */
14 
15 struct volumeid {
16 	u8	vid_unused[248];
17 	u8	vid_mac[8];	/* ASCII string "MOTOROLA" */
18 };
19 
20 /*
21  *	config block: second 256-bytes sector on disk
22  */
23 
24 struct dkconfig {
25 	u8	ios_unused0[128];
26 	__be32	ios_slcblk;	/* Slice table block number */
27 	__be16	ios_slccnt;	/* Number of entries in slice table */
28 	u8	ios_unused1[122];
29 };
30 
31 /*
32  *	combined volumeid and dkconfig block
33  */
34 
35 struct dkblk0 {
36 	struct volumeid dk_vid;
37 	struct dkconfig dk_ios;
38 };
39 
40 /*
41  *	Slice Table Structure
42  */
43 
44 struct slice {
45 	__be32	nblocks;		/* slice size (in blocks) */
46 	__be32	blkoff;			/* block offset of slice */
47 };
48 
49 
50 int sysv68_partition(struct parsed_partitions *state)
51 {
52 	int i, slices;
53 	int slot = 1;
54 	Sector sect;
55 	unsigned char *data;
56 	struct dkblk0 *b;
57 	struct slice *slice;
58 	char tmp[64];
59 
60 	data = read_part_sector(state, 0, &sect);
61 	if (!data)
62 		return -1;
63 
64 	b = (struct dkblk0 *)data;
65 	if (memcmp(b->dk_vid.vid_mac, "MOTOROLA", sizeof(b->dk_vid.vid_mac))) {
66 		put_dev_sector(sect);
67 		return 0;
68 	}
69 	slices = be16_to_cpu(b->dk_ios.ios_slccnt);
70 	i = be32_to_cpu(b->dk_ios.ios_slcblk);
71 	put_dev_sector(sect);
72 
73 	data = read_part_sector(state, i, &sect);
74 	if (!data)
75 		return -1;
76 
77 	slices -= 1; /* last slice is the whole disk */
78 	snprintf(tmp, sizeof(tmp), "sysV68: %s(s%u)", state->name, slices);
79 	strlcat(state->pp_buf, tmp, PAGE_SIZE);
80 	slice = (struct slice *)data;
81 	for (i = 0; i < slices; i++, slice++) {
82 		if (slot == state->limit)
83 			break;
84 		if (be32_to_cpu(slice->nblocks)) {
85 			put_partition(state, slot,
86 				be32_to_cpu(slice->blkoff),
87 				be32_to_cpu(slice->nblocks));
88 			snprintf(tmp, sizeof(tmp), "(s%u)", i);
89 			strlcat(state->pp_buf, tmp, PAGE_SIZE);
90 		}
91 		slot++;
92 	}
93 	strlcat(state->pp_buf, "\n", PAGE_SIZE);
94 	put_dev_sector(sect);
95 	return 1;
96 }
97