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/*		printk(KERN_INFO "Dev %s Sun disklabel: bad magic %04x\n",
78		       state->disk->disk_name, be16_to_cpu(label->magic)); */
79		put_dev_sector(sect);
80		return 0;
81	}
82	/* Look at the checksum */
83	ush = ((__be16 *) (label+1)) - 1;
84	for (csum = 0; ush >= ((__be16 *) label);)
85		csum ^= *ush--;
86	if (csum) {
87		printk("Dev %s Sun disklabel: Csum bad, label corrupted\n",
88		       state->disk->disk_name);
89		put_dev_sector(sect);
90		return 0;
91	}
92
93	/* Check to see if we can use the VTOC table */
94	use_vtoc = ((be32_to_cpu(label->vtoc.sanity) == SUN_VTOC_SANITY) &&
95		    (be32_to_cpu(label->vtoc.version) == 1) &&
96		    (be16_to_cpu(label->vtoc.nparts) <= 8));
97
98	/* Use 8 partition entries if not specified in validated VTOC */
99	nparts = (use_vtoc) ? be16_to_cpu(label->vtoc.nparts) : 8;
100
101	/*
102	 * So that old Linux-Sun partitions continue to work,
103	 * alow the VTOC to be used under the additional condition ...
104	 */
105	use_vtoc = use_vtoc || !(label->vtoc.sanity ||
106				 label->vtoc.version || label->vtoc.nparts);
107	spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
108	for (i = 0; i < nparts; i++, p++) {
109		unsigned long st_sector;
110		unsigned int num_sectors;
111
112		st_sector = be32_to_cpu(p->start_cylinder) * spc;
113		num_sectors = be32_to_cpu(p->num_sectors);
114		if (num_sectors) {
115			put_partition(state, slot, st_sector, num_sectors);
116			state->parts[slot].flags = 0;
117			if (use_vtoc) {
118				if (be16_to_cpu(label->vtoc.infos[i].id) == LINUX_RAID_PARTITION)
119					state->parts[slot].flags |= ADDPART_FLAG_RAID;
120				else if (be16_to_cpu(label->vtoc.infos[i].id) == SUN_WHOLE_DISK)
121					state->parts[slot].flags |= ADDPART_FLAG_WHOLEDISK;
122			}
123		}
124		slot++;
125	}
126	strlcat(state->pp_buf, "\n", PAGE_SIZE);
127	put_dev_sector(sect);
128	return 1;
129}
130