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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * fs/partitions/sun.c
4 *
5 * Code extracted from drivers/block/genhd.c
6 *
7 * Copyright (C) 1991-1998 Linus Torvalds
8 * Re-organised Feb 1998 Russell King
9 */
10
11#include "check.h"
12
13#define SUN_LABEL_MAGIC 0xDABE
14#define SUN_VTOC_SANITY 0x600DDEEE
15
16enum {
17 SUN_WHOLE_DISK = 5,
18 LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
19};
20
21int sun_partition(struct parsed_partitions *state)
22{
23 int i;
24 __be16 csum;
25 int slot = 1;
26 __be16 *ush;
27 Sector sect;
28 struct sun_disklabel {
29 unsigned char info[128]; /* Informative text string */
30 struct sun_vtoc {
31 __be32 version; /* Layout version */
32 char volume[8]; /* Volume name */
33 __be16 nparts; /* Number of partitions */
34 struct sun_info { /* Partition hdrs, sec 2 */
35 __be16 id;
36 __be16 flags;
37 } infos[8];
38 __be16 padding; /* Alignment padding */
39 __be32 bootinfo[3]; /* Info needed by mboot */
40 __be32 sanity; /* To verify vtoc sanity */
41 __be32 reserved[10]; /* Free space */
42 __be32 timestamp[8]; /* Partition timestamp */
43 } vtoc;
44 __be32 write_reinstruct; /* sectors to skip, writes */
45 __be32 read_reinstruct; /* sectors to skip, reads */
46 unsigned char spare[148]; /* Padding */
47 __be16 rspeed; /* Disk rotational speed */
48 __be16 pcylcount; /* Physical cylinder count */
49 __be16 sparecyl; /* extra sects per cylinder */
50 __be16 obs1; /* gap1 */
51 __be16 obs2; /* gap2 */
52 __be16 ilfact; /* Interleave factor */
53 __be16 ncyl; /* Data cylinder count */
54 __be16 nacyl; /* Alt. cylinder count */
55 __be16 ntrks; /* Tracks per cylinder */
56 __be16 nsect; /* Sectors per track */
57 __be16 obs3; /* bhead - Label head offset */
58 __be16 obs4; /* ppart - Physical Partition */
59 struct sun_partition {
60 __be32 start_cylinder;
61 __be32 num_sectors;
62 } partitions[8];
63 __be16 magic; /* Magic number */
64 __be16 csum; /* Label xor'd checksum */
65 } * label;
66 struct sun_partition *p;
67 unsigned long spc;
68 int use_vtoc;
69 int nparts;
70
71 label = read_part_sector(state, 0, &sect);
72 if (!label)
73 return -1;
74
75 p = label->partitions;
76 if (be16_to_cpu(label->magic) != SUN_LABEL_MAGIC) {
77 put_dev_sector(sect);
78 return 0;
79 }
80 /* Look at the checksum */
81 ush = ((__be16 *) (label+1)) - 1;
82 for (csum = 0; ush >= ((__be16 *) label);)
83 csum ^= *ush--;
84 if (csum) {
85 printk("Dev %s Sun disklabel: Csum bad, label corrupted\n",
86 state->disk->disk_name);
87 put_dev_sector(sect);
88 return 0;
89 }
90
91 /* Check to see if we can use the VTOC table */
92 use_vtoc = ((be32_to_cpu(label->vtoc.sanity) == SUN_VTOC_SANITY) &&
93 (be32_to_cpu(label->vtoc.version) == 1) &&
94 (be16_to_cpu(label->vtoc.nparts) <= 8));
95
96 /* Use 8 partition entries if not specified in validated VTOC */
97 nparts = (use_vtoc) ? be16_to_cpu(label->vtoc.nparts) : 8;
98
99 /*
100 * So that old Linux-Sun partitions continue to work,
101 * alow the VTOC to be used under the additional condition ...
102 */
103 use_vtoc = use_vtoc || !(label->vtoc.sanity ||
104 label->vtoc.version || label->vtoc.nparts);
105 spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
106 for (i = 0; i < nparts; i++, p++) {
107 unsigned long st_sector;
108 unsigned int num_sectors;
109
110 st_sector = be32_to_cpu(p->start_cylinder) * spc;
111 num_sectors = be32_to_cpu(p->num_sectors);
112 if (num_sectors) {
113 put_partition(state, slot, st_sector, num_sectors);
114 state->parts[slot].flags = 0;
115 if (use_vtoc) {
116 if (be16_to_cpu(label->vtoc.infos[i].id) == LINUX_RAID_PARTITION)
117 state->parts[slot].flags |= ADDPART_FLAG_RAID;
118 else if (be16_to_cpu(label->vtoc.infos[i].id) == SUN_WHOLE_DISK)
119 state->parts[slot].flags |= ADDPART_FLAG_WHOLEDISK;
120 }
121 }
122 slot++;
123 }
124 seq_buf_puts(&state->pp_buf, "\n");
125 put_dev_sector(sect);
126 return 1;
127}