1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * fs/partitions/sgi.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Code extracted from drivers/block/genhd.c
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include "check.h"
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #define SGI_LABEL_MAGIC 0x0be5a941
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun enum {
13*4882a593Smuzhiyun LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
14*4882a593Smuzhiyun };
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun struct sgi_disklabel {
17*4882a593Smuzhiyun __be32 magic_mushroom; /* Big fat spliff... */
18*4882a593Smuzhiyun __be16 root_part_num; /* Root partition number */
19*4882a593Smuzhiyun __be16 swap_part_num; /* Swap partition number */
20*4882a593Smuzhiyun s8 boot_file[16]; /* Name of boot file for ARCS */
21*4882a593Smuzhiyun u8 _unused0[48]; /* Device parameter useless crapola.. */
22*4882a593Smuzhiyun struct sgi_volume {
23*4882a593Smuzhiyun s8 name[8]; /* Name of volume */
24*4882a593Smuzhiyun __be32 block_num; /* Logical block number */
25*4882a593Smuzhiyun __be32 num_bytes; /* How big, in bytes */
26*4882a593Smuzhiyun } volume[15];
27*4882a593Smuzhiyun struct sgi_partition {
28*4882a593Smuzhiyun __be32 num_blocks; /* Size in logical blocks */
29*4882a593Smuzhiyun __be32 first_block; /* First logical block */
30*4882a593Smuzhiyun __be32 type; /* Type of this partition */
31*4882a593Smuzhiyun } partitions[16];
32*4882a593Smuzhiyun __be32 csum; /* Disk label checksum */
33*4882a593Smuzhiyun __be32 _unused1; /* Padding */
34*4882a593Smuzhiyun };
35*4882a593Smuzhiyun
sgi_partition(struct parsed_partitions * state)36*4882a593Smuzhiyun int sgi_partition(struct parsed_partitions *state)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun int i, csum;
39*4882a593Smuzhiyun __be32 magic;
40*4882a593Smuzhiyun int slot = 1;
41*4882a593Smuzhiyun unsigned int start, blocks;
42*4882a593Smuzhiyun __be32 *ui, cs;
43*4882a593Smuzhiyun Sector sect;
44*4882a593Smuzhiyun struct sgi_disklabel *label;
45*4882a593Smuzhiyun struct sgi_partition *p;
46*4882a593Smuzhiyun char b[BDEVNAME_SIZE];
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun label = read_part_sector(state, 0, §);
49*4882a593Smuzhiyun if (!label)
50*4882a593Smuzhiyun return -1;
51*4882a593Smuzhiyun p = &label->partitions[0];
52*4882a593Smuzhiyun magic = label->magic_mushroom;
53*4882a593Smuzhiyun if(be32_to_cpu(magic) != SGI_LABEL_MAGIC) {
54*4882a593Smuzhiyun /*printk("Dev %s SGI disklabel: bad magic %08x\n",
55*4882a593Smuzhiyun bdevname(bdev, b), be32_to_cpu(magic));*/
56*4882a593Smuzhiyun put_dev_sector(sect);
57*4882a593Smuzhiyun return 0;
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun ui = ((__be32 *) (label + 1)) - 1;
60*4882a593Smuzhiyun for(csum = 0; ui >= ((__be32 *) label);) {
61*4882a593Smuzhiyun cs = *ui--;
62*4882a593Smuzhiyun csum += be32_to_cpu(cs);
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun if(csum) {
65*4882a593Smuzhiyun printk(KERN_WARNING "Dev %s SGI disklabel: csum bad, label corrupted\n",
66*4882a593Smuzhiyun bdevname(state->bdev, b));
67*4882a593Smuzhiyun put_dev_sector(sect);
68*4882a593Smuzhiyun return 0;
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun /* All SGI disk labels have 16 partitions, disks under Linux only
71*4882a593Smuzhiyun * have 15 minor's. Luckily there are always a few zero length
72*4882a593Smuzhiyun * partitions which we don't care about so we never overflow the
73*4882a593Smuzhiyun * current_minor.
74*4882a593Smuzhiyun */
75*4882a593Smuzhiyun for(i = 0; i < 16; i++, p++) {
76*4882a593Smuzhiyun blocks = be32_to_cpu(p->num_blocks);
77*4882a593Smuzhiyun start = be32_to_cpu(p->first_block);
78*4882a593Smuzhiyun if (blocks) {
79*4882a593Smuzhiyun put_partition(state, slot, start, blocks);
80*4882a593Smuzhiyun if (be32_to_cpu(p->type) == LINUX_RAID_PARTITION)
81*4882a593Smuzhiyun state->parts[slot].flags = ADDPART_FLAG_RAID;
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun slot++;
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun strlcat(state->pp_buf, "\n", PAGE_SIZE);
86*4882a593Smuzhiyun put_dev_sector(sect);
87*4882a593Smuzhiyun return 1;
88*4882a593Smuzhiyun }
89