xref: /openbmc/linux/block/partitions/sun.c (revision 9cfc5c90)
1 /*
2  *  fs/partitions/sun.c
3  *
4  *  Code extracted from drivers/block/genhd.c
5  *
6  *  Copyright (C) 1991-1998  Linus Torvalds
7  *  Re-organised Feb 1998 Russell King
8  */
9 
10 #include "check.h"
11 #include "sun.h"
12 
13 int sun_partition(struct parsed_partitions *state)
14 {
15 	int i;
16 	__be16 csum;
17 	int slot = 1;
18 	__be16 *ush;
19 	Sector sect;
20 	struct sun_disklabel {
21 		unsigned char info[128];   /* Informative text string */
22 		struct sun_vtoc {
23 		    __be32 version;     /* Layout version */
24 		    char   volume[8];   /* Volume name */
25 		    __be16 nparts;      /* Number of partitions */
26 		    struct sun_info {           /* Partition hdrs, sec 2 */
27 			__be16 id;
28 			__be16 flags;
29 		    } infos[8];
30 		    __be16 padding;     /* Alignment padding */
31 		    __be32 bootinfo[3];  /* Info needed by mboot */
32 		    __be32 sanity;       /* To verify vtoc sanity */
33 		    __be32 reserved[10]; /* Free space */
34 		    __be32 timestamp[8]; /* Partition timestamp */
35 		} vtoc;
36 		__be32 write_reinstruct; /* sectors to skip, writes */
37 		__be32 read_reinstruct;  /* sectors to skip, reads */
38 		unsigned char spare[148]; /* Padding */
39 		__be16 rspeed;     /* Disk rotational speed */
40 		__be16 pcylcount;  /* Physical cylinder count */
41 		__be16 sparecyl;   /* extra sects per cylinder */
42 		__be16 obs1;       /* gap1 */
43 		__be16 obs2;       /* gap2 */
44 		__be16 ilfact;     /* Interleave factor */
45 		__be16 ncyl;       /* Data cylinder count */
46 		__be16 nacyl;      /* Alt. cylinder count */
47 		__be16 ntrks;      /* Tracks per cylinder */
48 		__be16 nsect;      /* Sectors per track */
49 		__be16 obs3;       /* bhead - Label head offset */
50 		__be16 obs4;       /* ppart - Physical Partition */
51 		struct sun_partition {
52 			__be32 start_cylinder;
53 			__be32 num_sectors;
54 		} partitions[8];
55 		__be16 magic;      /* Magic number */
56 		__be16 csum;       /* Label xor'd checksum */
57 	} * label;
58 	struct sun_partition *p;
59 	unsigned long spc;
60 	char b[BDEVNAME_SIZE];
61 	int use_vtoc;
62 	int nparts;
63 
64 	label = read_part_sector(state, 0, &sect);
65 	if (!label)
66 		return -1;
67 
68 	p = label->partitions;
69 	if (be16_to_cpu(label->magic) != SUN_LABEL_MAGIC) {
70 /*		printk(KERN_INFO "Dev %s Sun disklabel: bad magic %04x\n",
71 		       bdevname(bdev, b), be16_to_cpu(label->magic)); */
72 		put_dev_sector(sect);
73 		return 0;
74 	}
75 	/* Look at the checksum */
76 	ush = ((__be16 *) (label+1)) - 1;
77 	for (csum = 0; ush >= ((__be16 *) label);)
78 		csum ^= *ush--;
79 	if (csum) {
80 		printk("Dev %s Sun disklabel: Csum bad, label corrupted\n",
81 		       bdevname(state->bdev, b));
82 		put_dev_sector(sect);
83 		return 0;
84 	}
85 
86 	/* Check to see if we can use the VTOC table */
87 	use_vtoc = ((be32_to_cpu(label->vtoc.sanity) == SUN_VTOC_SANITY) &&
88 		    (be32_to_cpu(label->vtoc.version) == 1) &&
89 		    (be16_to_cpu(label->vtoc.nparts) <= 8));
90 
91 	/* Use 8 partition entries if not specified in validated VTOC */
92 	nparts = (use_vtoc) ? be16_to_cpu(label->vtoc.nparts) : 8;
93 
94 	/*
95 	 * So that old Linux-Sun partitions continue to work,
96 	 * alow the VTOC to be used under the additional condition ...
97 	 */
98 	use_vtoc = use_vtoc || !(label->vtoc.sanity ||
99 				 label->vtoc.version || label->vtoc.nparts);
100 	spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
101 	for (i = 0; i < nparts; i++, p++) {
102 		unsigned long st_sector;
103 		unsigned int num_sectors;
104 
105 		st_sector = be32_to_cpu(p->start_cylinder) * spc;
106 		num_sectors = be32_to_cpu(p->num_sectors);
107 		if (num_sectors) {
108 			put_partition(state, slot, st_sector, num_sectors);
109 			state->parts[slot].flags = 0;
110 			if (use_vtoc) {
111 				if (be16_to_cpu(label->vtoc.infos[i].id) == LINUX_RAID_PARTITION)
112 					state->parts[slot].flags |= ADDPART_FLAG_RAID;
113 				else if (be16_to_cpu(label->vtoc.infos[i].id) == SUN_WHOLE_DISK)
114 					state->parts[slot].flags |= ADDPART_FLAG_WHOLEDISK;
115 			}
116 		}
117 		slot++;
118 	}
119 	strlcat(state->pp_buf, "\n", PAGE_SIZE);
120 	put_dev_sector(sect);
121 	return 1;
122 }
123