LXR linux/block/partitions/mac.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  fs/partitions/mac.c
   4 *
   5 *  Code extracted from drivers/block/genhd.c
   6 *  Copyright (C) 1991-1998  Linus Torvalds
   7 *  Re-organised Feb 1998 Russell King
   8 */
   9
  10#include <linux/ctype.h>
  11#include "check.h"
  12#include "mac.h"
  13
  14#ifdef CONFIG_PPC_PMAC
  15#include <asm/machdep.h>
  16extern void note_bootable_part(dev_t dev, int part, int goodness);
  17#endif
  18
  19/*
  20 * Code to understand MacOS partition tables.
  21 */
  22
  23static inline void mac_fix_string(char *stg, int len)
  24{
  25        int i;
  26
  27        for (i = len - 1; i >= 0 && stg[i] == ' '; i--)
  28                stg[i] = 0;
  29}
  30
  31int mac_partition(struct parsed_partitions *state)
  32{
  33        Sector sect;
  34        unsigned char *data;
  35        int slot, blocks_in_map;
  36        unsigned secsize, datasize, partoffset;
  37#ifdef CONFIG_PPC_PMAC
  38        int found_root = 0;
  39        int found_root_goodness = 0;
  40#endif
  41        struct mac_partition *part;
  42        struct mac_driver_desc *md;
  43
  44        /* Get 0th block and look at the first partition map entry. */
  45        md = read_part_sector(state, 0, &sect);
  46        if (!md)
  47                return -1;
  48        if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) {
  49                put_dev_sector(sect);
  50                return 0;
  51        }
  52        secsize = be16_to_cpu(md->block_size);
  53        put_dev_sector(sect);
  54        datasize = round_down(secsize, 512);
  55        data = read_part_sector(state, datasize / 512, &sect);
  56        if (!data)
  57                return -1;
  58        partoffset = secsize % 512;
  59        if (partoffset + sizeof(*part) > datasize)
  60                return -1;
  61        part = (struct mac_partition *) (data + partoffset);
  62        if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) {
  63                put_dev_sector(sect);
  64                return 0;               /* not a MacOS disk */
  65        }
  66        blocks_in_map = be32_to_cpu(part->map_count);
  67        if (blocks_in_map < 0 || blocks_in_map >= DISK_MAX_PARTS) {
  68                put_dev_sector(sect);
  69                return 0;
  70        }
  71
  72        if (blocks_in_map >= state->limit)
  73                blocks_in_map = state->limit - 1;
  74
  75        strlcat(state->pp_buf, " [mac]", PAGE_SIZE);
  76        for (slot = 1; slot <= blocks_in_map; ++slot) {
  77                int pos = slot * secsize;
  78                put_dev_sector(sect);
  79                data = read_part_sector(state, pos/512, &sect);
  80                if (!data)
  81                        return -1;
  82                part = (struct mac_partition *) (data + pos%512);
  83                if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC)
  84                        break;
  85                put_partition(state, slot,
  86                        be32_to_cpu(part->start_block) * (secsize/512),
  87                        be32_to_cpu(part->block_count) * (secsize/512));
  88
  89                if (!strncasecmp(part->type, "Linux_RAID", 10))
  90                        state->parts[slot].flags = ADDPART_FLAG_RAID;
  91#ifdef CONFIG_PPC_PMAC
  92                /*
  93                 * If this is the first bootable partition, tell the
  94                 * setup code, in case it wants to make this the root.
  95                 */
  96                if (machine_is(powermac)) {
  97                        int goodness = 0;
  98
  99                        mac_fix_string(part->processor, 16);
 100                        mac_fix_string(part->name, 32);
 101                        mac_fix_string(part->type, 32);                                 
 102                    
 103                        if ((be32_to_cpu(part->status) & MAC_STATUS_BOOTABLE)
 104                            && strcasecmp(part->processor, "powerpc") == 0)
 105                                goodness++;
 106
 107                        if (strcasecmp(part->type, "Apple_UNIX_SVR2") == 0
 108                            || (strncasecmp(part->type, "Linux", 5) == 0
 109                                && strcasecmp(part->type, "Linux_swap") != 0)) {
 110                                int i, l;
 111
 112                                goodness++;
 113                                l = strlen(part->name);
 114                                if (strcmp(part->name, "/") == 0)
 115                                        goodness++;
 116                                for (i = 0; i <= l - 4; ++i) {
 117                                        if (strncasecmp(part->name + i, "root",
 118                                                     4) == 0) {
 119                                                goodness += 2;
 120                                                break;
 121                                        }
 122                                }
 123                                if (strncasecmp(part->name, "swap", 4) == 0)
 124                                        goodness--;
 125                        }
 126
 127                        if (goodness > found_root_goodness) {
 128                                found_root = slot;
 129                                found_root_goodness = goodness;
 130                        }
 131                }
 132#endif /* CONFIG_PPC_PMAC */
 133        }
 134#ifdef CONFIG_PPC_PMAC
 135        if (found_root_goodness)
 136                note_bootable_part(state->bdev->bd_dev, found_root,
 137                                   found_root_goodness);
 138#endif
 139
 140        put_dev_sector(sect);
 141        strlcat(state->pp_buf, "\n", PAGE_SIZE);
 142        return 1;
 143}
 144