block/partitions/check.c

   1 /*
   2  *  fs/partitions/check.c
   3  *
   4  *  Code extracted from drivers/block/genhd.c
   5  *  Copyright (C) 1991-1998  Linus Torvalds
   6  *  Re-organised Feb 1998 Russell King
   7  *
   8  *  We now have independent partition support from the
   9  *  block drivers, which allows all the partition code to
  10  *  be grouped in one location, and it to be mostly self
  11  *  contained.
  12  *
  13  *  Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
  14  */
  15
  16 #include <linux/slab.h>
  17 #include <linux/vmalloc.h>
  18 #include <linux/ctype.h>
  19 #include <linux/genhd.h>
  20
  21 #include "check.h"
  22
  23 #include "acorn.h"
  24 #include "amiga.h"
  25 #include "atari.h"
  26 #include "ldm.h"
  27 #include "mac.h"
  28 #include "msdos.h"
  29 #include "osf.h"
  30 #include "sgi.h"
  31 #include "sun.h"
  32 #include "ibm.h"
  33 #include "ultrix.h"
  34 #include "efi.h"
  35 #include "karma.h"
  36 #include "sysv68.h"
  37
  38 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
  39
  40 static int (*check_part[])(struct parsed_partitions *) = {
  41         /*
  42          * Probe partition formats with tables at disk address 0
  43          * that also have an ADFS boot block at 0xdc0.
  44          */
  45 #ifdef CONFIG_ACORN_PARTITION_ICS
  46         adfspart_check_ICS,
  47 #endif
  48 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
  49         adfspart_check_POWERTEC,
  50 #endif
  51 #ifdef CONFIG_ACORN_PARTITION_EESOX
  52         adfspart_check_EESOX,
  53 #endif
  54
  55         /*
  56          * Now move on to formats that only have partition info at
  57          * disk address 0xdc0.  Since these may also have stale
  58          * PC/BIOS partition tables, they need to come before
  59          * the msdos entry.
  60          */
  61 #ifdef CONFIG_ACORN_PARTITION_CUMANA
  62         adfspart_check_CUMANA,
  63 #endif
  64 #ifdef CONFIG_ACORN_PARTITION_ADFS
  65         adfspart_check_ADFS,
  66 #endif
  67
  68 #ifdef CONFIG_EFI_PARTITION
  69         efi_partition,          /* this must come before msdos */
  70 #endif
  71 #ifdef CONFIG_SGI_PARTITION
  72         sgi_partition,
  73 #endif
  74 #ifdef CONFIG_LDM_PARTITION
  75         ldm_partition,          /* this must come before msdos */
  76 #endif
  77 #ifdef CONFIG_MSDOS_PARTITION
  78         msdos_partition,
  79 #endif
  80 #ifdef CONFIG_OSF_PARTITION
  81         osf_partition,
  82 #endif
  83 #ifdef CONFIG_SUN_PARTITION
  84         sun_partition,
  85 #endif
  86 #ifdef CONFIG_AMIGA_PARTITION
  87         amiga_partition,
  88 #endif
  89 #ifdef CONFIG_ATARI_PARTITION
  90         atari_partition,
  91 #endif
  92 #ifdef CONFIG_MAC_PARTITION
  93         mac_partition,
  94 #endif
  95 #ifdef CONFIG_ULTRIX_PARTITION
  96         ultrix_partition,
  97 #endif
  98 #ifdef CONFIG_IBM_PARTITION
  99         ibm_partition,
 100 #endif
 101 #ifdef CONFIG_KARMA_PARTITION
 102         karma_partition,
 103 #endif
 104 #ifdef CONFIG_SYSV68_PARTITION
 105         sysv68_partition,
 106 #endif
 107         NULL
 108 };
 109
 110 static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
 111 {
 112         struct parsed_partitions *state;
 113         int nr;
 114
 115         state = kzalloc(sizeof(*state), GFP_KERNEL);
 116         if (!state)
 117                 return NULL;
 118
 119         nr = disk_max_parts(hd);
 120         state->parts = vzalloc(nr * sizeof(state->parts[0]));
 121         if (!state->parts) {
 122                 kfree(state);
 123                 return NULL;
 124         }
 125
 126         state->limit = nr;
 127
 128         return state;
 129 }
 130
 131 void free_partitions(struct parsed_partitions *state)
 132 {
 133         vfree(state->parts);
 134         kfree(state);
 135 }
 136
 137 struct parsed_partitions *
 138 check_partition(struct gendisk *hd, struct block_device *bdev)
 139 {
 140         struct parsed_partitions *state;
 141         int i, res, err;
 142
 143         state = allocate_partitions(hd);
 144         if (!state)
 145                 return NULL;
 146         state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
 147         if (!state->pp_buf) {
 148                 free_partitions(state);
 149                 return NULL;
 150         }
 151         state->pp_buf[0] = '\0';
 152
 153         state->bdev = bdev;
 154         disk_name(hd, 0, state->name);
 155         snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
 156         if (isdigit(state->name[strlen(state->name)-1]))
 157                 sprintf(state->name, "p");
 158
 159         i = res = err = 0;
 160         while (!res && check_part[i]) {
 161                 memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
 162                 res = check_part[i++](state);
 163                 if (res < 0) {
 164                         /* We have hit an I/O error which we don't report now.
 165                         * But record it, and let the others do their job.
 166                         */
 167                         err = res;
 168                         res = 0;
 169                 }
 170
 171         }
 172         if (res > 0) {
 173                 printk(KERN_INFO "%s", state->pp_buf);
 174
 175                 free_page((unsigned long)state->pp_buf);
 176                 return state;
 177         }
 178         if (state->access_beyond_eod)
 179                 err = -ENOSPC;
 180         if (err)
 181         /* The partition is unrecognized. So report I/O errors if there were any */
 182                 res = err;
 183         if (!res)
 184                 strlcat(state->pp_buf, " unknown partition table\n", PAGE_SIZE);
 185         else if (warn_no_part)
 186                 strlcat(state->pp_buf, " unable to read partition table\n", PAGE_SIZE);
 187
 188         printk(KERN_INFO "%s", state->pp_buf);
 189
 190         free_page((unsigned long)state->pp_buf);
 191         free_partitions(state);
 192         return ERR_PTR(res);
 193 }