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        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