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 "rk.h"
  24 #include "acorn.h"
  25 #include "amiga.h"
  26 #include "atari.h"
  27 #include "ldm.h"
  28 #include "mac.h"
  29 #include "msdos.h"
  30 #include "osf.h"
  31 #include "sgi.h"
  32 #include "sun.h"
  33 #include "ibm.h"
  34 #include "ultrix.h"
  35 #include "efi.h"
  36 #include "karma.h"
  37 #include "sysv68.h"
  38 #include "cmdline.h"
  39
  40 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
  41
  42 static int (*check_part[])(struct parsed_partitions *) = {
  43         /*
  44          * Probe partition formats with tables at disk address 0
  45          * that also have an ADFS boot block at 0xdc0.
  46          */
  47 #ifdef CONFIG_ACORN_PARTITION_ICS
  48         adfspart_check_ICS,
  49 #endif
  50 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
  51         adfspart_check_POWERTEC,
  52 #endif
  53 #ifdef CONFIG_ACORN_PARTITION_EESOX
  54         adfspart_check_EESOX,
  55 #endif
  56
  57         /*
  58          * Now move on to formats that only have partition info at
  59          * disk address 0xdc0.  Since these may also have stale
  60          * PC/BIOS partition tables, they need to come before
  61          * the msdos entry.
  62          */
  63 #ifdef CONFIG_ACORN_PARTITION_CUMANA
  64         adfspart_check_CUMANA,
  65 #endif
  66 #ifdef CONFIG_ACORN_PARTITION_ADFS
  67         adfspart_check_ADFS,
  68 #endif
  69
  70 #ifdef CONFIG_RK_PARTITION
  71         rkpart_partition,
  72 #endif
  73 #ifdef CONFIG_CMDLINE_PARTITION
  74         cmdline_partition,
  75 #endif
  76 #ifdef CONFIG_EFI_PARTITION
  77         efi_partition,          /* this must come before msdos */
  78 #endif
  79 #ifdef CONFIG_SGI_PARTITION
  80         sgi_partition,
  81 #endif
  82 #ifdef CONFIG_LDM_PARTITION
  83         ldm_partition,          /* this must come before msdos */
  84 #endif
  85 #ifdef CONFIG_MSDOS_PARTITION
  86         msdos_partition,
  87 #endif
  88 #ifdef CONFIG_OSF_PARTITION
  89         osf_partition,
  90 #endif
  91 #ifdef CONFIG_SUN_PARTITION
  92         sun_partition,
  93 #endif
  94 #ifdef CONFIG_AMIGA_PARTITION
  95         amiga_partition,
  96 #endif
  97 #ifdef CONFIG_ATARI_PARTITION
  98         atari_partition,
  99 #endif
 100 #ifdef CONFIG_MAC_PARTITION
 101         mac_partition,
 102 #endif
 103 #ifdef CONFIG_ULTRIX_PARTITION
 104         ultrix_partition,
 105 #endif
 106 #ifdef CONFIG_IBM_PARTITION
 107         ibm_partition,
 108 #endif
 109 #ifdef CONFIG_KARMA_PARTITION
 110         karma_partition,
 111 #endif
 112 #ifdef CONFIG_SYSV68_PARTITION
 113         sysv68_partition,
 114 #endif
 115         NULL
 116 };
 117
 118 static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
 119 {
 120         struct parsed_partitions *state;
 121         int nr;
 122
 123         state = kzalloc(sizeof(*state), GFP_KERNEL);
 124         if (!state)
 125                 return NULL;
 126
 127         nr = disk_max_parts(hd);
 128         state->parts = vzalloc(nr * sizeof(state->parts[0]));
 129         if (!state->parts) {
 130                 kfree(state);
 131                 return NULL;
 132         }
 133
 134         state->limit = nr;
 135
 136         return state;
 137 }
 138
 139 void free_partitions(struct parsed_partitions *state)
 140 {
 141         vfree(state->parts);
 142         kfree(state);
 143 }
 144
 145 struct parsed_partitions *
 146 check_partition(struct gendisk *hd, struct block_device *bdev)
 147 {
 148         struct parsed_partitions *state;
 149         int i, res, err;
 150
 151         state = allocate_partitions(hd);
 152         if (!state)
 153                 return NULL;
 154         state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
 155         if (!state->pp_buf) {
 156                 free_partitions(state);
 157                 return NULL;
 158         }
 159         state->pp_buf[0] = '\0';
 160
 161         state->bdev = bdev;
 162         disk_name(hd, 0, state->name);
 163         snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
 164         if (isdigit(state->name[strlen(state->name)-1]))
 165                 sprintf(state->name, "p");
 166
 167         i = res = err = 0;
 168         while (!res && check_part[i]) {
 169                 memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
 170                 res = check_part[i++](state);
 171                 if (res < 0) {
 172                         /* We have hit an I/O error which we don't report now.
 173                         * But record it, and let the others do their job.
 174                         */
 175                         err = res;
 176                         res = 0;
 177                 }
 178
 179         }
 180         if (res > 0) {
 181                 printk(KERN_INFO "%s", state->pp_buf);
 182
 183                 free_page((unsigned long)state->pp_buf);
 184                 return state;
 185         }
 186         if (state->access_beyond_eod)
 187                 err = -ENOSPC;
 188         if (err)
 189         /* The partition is unrecognized. So report I/O errors if there were any */
 190                 res = err;
 191         if (res) {
 192                 if (warn_no_part)
 193                         strlcat(state->pp_buf,
 194                                 " unable to read partition table\n", PAGE_SIZE);
 195                 printk(KERN_INFO "%s", state->pp_buf);
 196         }
 197
 198         free_page((unsigned long)state->pp_buf);
 199         free_partitions(state);
 200         return ERR_PTR(res);
 201 }