LXR linux/block/partitions/sun.c

   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        char b[BDEVNAME_SIZE];
  69        int use_vtoc;
  70        int nparts;
  71
  72        label = read_part_sector(state, 0, &sect);
  73        if (!label)
  74                return -1;
  75
  76        p = label->partitions;
  77        if (be16_to_cpu(label->magic) != SUN_LABEL_MAGIC) {
  78/*              printk(KERN_INFO "Dev %s Sun disklabel: bad magic %04x\n",
  79                       bdevname(bdev, b), be16_to_cpu(label->magic)); */
  80                put_dev_sector(sect);
  81                return 0;
  82        }
  83        /* Look at the checksum */
  84        ush = ((__be16 *) (label+1)) - 1;
  85        for (csum = 0; ush >= ((__be16 *) label);)
  86                csum ^= *ush--;
  87        if (csum) {
  88                printk("Dev %s Sun disklabel: Csum bad, label corrupted\n",
  89                       bdevname(state->bdev, b));
  90                put_dev_sector(sect);
  91                return 0;
  92        }
  93
  94        /* Check to see if we can use the VTOC table */
  95        use_vtoc = ((be32_to_cpu(label->vtoc.sanity) == SUN_VTOC_SANITY) &&
  96                    (be32_to_cpu(label->vtoc.version) == 1) &&
  97                    (be16_to_cpu(label->vtoc.nparts) <= 8));
  98
  99        /* Use 8 partition entries if not specified in validated VTOC */
 100        nparts = (use_vtoc) ? be16_to_cpu(label->vtoc.nparts) : 8;
 101
 102        /*
 103         * So that old Linux-Sun partitions continue to work,
 104         * alow the VTOC to be used under the additional condition ...
 105         */
 106        use_vtoc = use_vtoc || !(label->vtoc.sanity ||
 107                                 label->vtoc.version || label->vtoc.nparts);
 108        spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
 109        for (i = 0; i < nparts; i++, p++) {
 110                unsigned long st_sector;
 111                unsigned int num_sectors;
 112
 113                st_sector = be32_to_cpu(p->start_cylinder) * spc;
 114                num_sectors = be32_to_cpu(p->num_sectors);
 115                if (num_sectors) {
 116                        put_partition(state, slot, st_sector, num_sectors);
 117                        state->parts[slot].flags = 0;
 118                        if (use_vtoc) {
 119                                if (be16_to_cpu(label->vtoc.infos[i].id) == LINUX_RAID_PARTITION)
 120                                        state->parts[slot].flags |= ADDPART_FLAG_RAID;
 121                                else if (be16_to_cpu(label->vtoc.infos[i].id) == SUN_WHOLE_DISK)
 122                                        state->parts[slot].flags |= ADDPART_FLAG_WHOLEDISK;
 123                        }
 124                }
 125                slot++;
 126        }
 127        strlcat(state->pp_buf, "\n", PAGE_SIZE);
 128        put_dev_sector(sect);
 129        return 1;
 130}
 131