fs/udf/partition.c

   1 /*
   2  * partition.c
   3  *
   4  * PURPOSE
   5  *      Partition handling routines for the OSTA-UDF(tm) filesystem.
   6  *
   7  * CONTACTS
   8  *      E-mail regarding any portion of the Linux UDF file system should be
   9  *      directed to the development team mailing list (run by majordomo):
  10  *              linux_udf@hpesjro.fc.hp.com
  11  *
  12  * COPYRIGHT
  13  *      This file is distributed under the terms of the GNU General Public
  14  *      License (GPL). Copies of the GPL can be obtained from:
  15  *              ftp://prep.ai.mit.edu/pub/gnu/GPL
  16  *      Each contributing author retains all rights to their own work.
  17  *
  18  *  (C) 1998-2001 Ben Fennema
  19  *
  20  * HISTORY
  21  *
  22  * 12/06/98 blf  Created file.
  23  *
  24  */
  25
  26 #include "udfdecl.h"
  27 #include "udf_sb.h"
  28 #include "udf_i.h"
  29
  30 #include <linux/fs.h>
  31 #include <linux/string.h>
  32 #include <linux/udf_fs.h>
  33 #include <linux/slab.h>
  34 #include <linux/buffer_head.h>
  35
  36 inline uint32_t udf_get_pblock(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
  37 {
  38         if (partition >= UDF_SB_NUMPARTS(sb))
  39         {
  40                 udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
  41                         block, partition, offset);
  42                 return 0xFFFFFFFF;
  43         }
  44         if (UDF_SB_PARTFUNC(sb, partition))
  45                 return UDF_SB_PARTFUNC(sb, partition)(sb, block, partition, offset);
  46         else
  47                 return UDF_SB_PARTROOT(sb, partition) + block + offset;
  48 }
  49
  50 uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
  51 {
  52         struct buffer_head *bh = NULL;
  53         uint32_t newblock;
  54         uint32_t index;
  55         uint32_t loc;
  56
  57         index = (sb->s_blocksize - UDF_SB_TYPEVIRT(sb,partition).s_start_offset) / sizeof(uint32_t);
  58
  59         if (block > UDF_SB_TYPEVIRT(sb,partition).s_num_entries)
  60         {
  61                 udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
  62                         block, UDF_SB_TYPEVIRT(sb,partition).s_num_entries);
  63                 return 0xFFFFFFFF;
  64         }
  65
  66         if (block >= index)
  67         {
  68                 block -= index;
  69                 newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
  70                 index = block % (sb->s_blocksize / sizeof(uint32_t));
  71         }
  72         else
  73         {
  74                 newblock = 0;
  75                 index = UDF_SB_TYPEVIRT(sb,partition).s_start_offset / sizeof(uint32_t) + block;
  76         }
  77
  78         loc = udf_block_map(UDF_SB_VAT(sb), newblock);
  79
  80         if (!(bh = sb_bread(sb, loc)))
  81         {
  82                 udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]\n",
  83                         sb, block, partition, loc, index);
  84                 return 0xFFFFFFFF;
  85         }
  86
  87         loc = le32_to_cpu(((uint32_t *)bh->b_data)[index]);
  88
  89         udf_release_data(bh);
  90
  91         if (UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum == partition)
  92         {
  93                 udf_debug("recursive call to udf_get_pblock!\n");
  94                 return 0xFFFFFFFF;
  95         }
  96
  97         return udf_get_pblock(sb, loc, UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum, offset);
  98 }
  99
 100 inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
 101 {
 102         return udf_get_pblock_virt15(sb, block, partition, offset);
 103 }
 104
 105 uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
 106 {
 107         int i;
 108         struct sparingTable *st = NULL;
 109         uint32_t packet = (block + offset) & ~(UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1);
 110
 111         for (i=0; i<4; i++)
 112         {
 113                 if (UDF_SB_TYPESPAR(sb,partition).s_spar_map[i] != NULL)
 114                 {
 115                         st = (struct sparingTable *)UDF_SB_TYPESPAR(sb,partition).s_spar_map[i]->b_data;
 116                         break;
 117                 }
 118         }
 119
 120         if (st)
 121         {
 122                 for (i=0; i<st->reallocationTableLen; i++)
 123                 {
 124                         if (le32_to_cpu(st->mapEntry[i].origLocation) >= 0xFFFFFFF0)
 125                                 break;
 126                         else if (le32_to_cpu(st->mapEntry[i].origLocation) == packet)
 127                         {
 128                                 return le32_to_cpu(st->mapEntry[i].mappedLocation) +
 129                                         ((block + offset) & (UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1));
 130                         }
 131                         else if (le32_to_cpu(st->mapEntry[i].origLocation) > packet)
 132                                 break;
 133                 }
 134         }
 135         return UDF_SB_PARTROOT(sb,partition) + block + offset;
 136 }
 137
 138 int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
 139 {
 140         struct udf_sparing_data *sdata;
 141         struct sparingTable *st = NULL;
 142         struct sparingEntry mapEntry;
 143         uint32_t packet;
 144         int i, j, k, l;
 145
 146         for (i=0; i<UDF_SB_NUMPARTS(sb); i++)
 147         {
 148                 if (old_block > UDF_SB_PARTROOT(sb,i) &&
 149                     old_block < UDF_SB_PARTROOT(sb,i) + UDF_SB_PARTLEN(sb,i))
 150                 {
 151                         sdata = &UDF_SB_TYPESPAR(sb,i);
 152                         packet = (old_block - UDF_SB_PARTROOT(sb,i)) & ~(sdata->s_packet_len - 1);
 153
 154                         for (j=0; j<4; j++)
 155                         {
 156                                 if (UDF_SB_TYPESPAR(sb,i).s_spar_map[j] != NULL)
 157                                 {
 158                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 159                                         break;
 160                                 }
 161                         }
 162
 163                         if (!st)
 164                                 return 1;
 165
 166                         for (k=0; k<st->reallocationTableLen; k++)
 167                         {
 168                                 if (le32_to_cpu(st->mapEntry[k].origLocation) == 0xFFFFFFFF)
 169                                 {
 170                                         for (; j<4; j++)
 171                                         {
 172                                                 if (sdata->s_spar_map[j])
 173                                                 {
 174                                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 175                                                         st->mapEntry[k].origLocation = cpu_to_le32(packet);
 176                                                         udf_update_tag((char *)st, sizeof(struct sparingTable) + st->reallocationTableLen * sizeof(struct sparingEntry));
 177                                                         mark_buffer_dirty(sdata->s_spar_map[j]);
 178                                                 }
 179                                         }
 180                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 181                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 182                                         return 0;
 183                                 }
 184                                 else if (le32_to_cpu(st->mapEntry[k].origLocation) == packet)
 185                                 {
 186                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 187                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 188                                         return 0;
 189                                 }
 190                                 else if (le32_to_cpu(st->mapEntry[k].origLocation) > packet)
 191                                         break;
 192                         }
 193                         for (l=k; l<st->reallocationTableLen; l++)
 194                         {
 195                                 if (le32_to_cpu(st->mapEntry[l].origLocation) == 0xFFFFFFFF)
 196                                 {
 197                                         for (; j<4; j++)
 198                                         {
 199                                                 if (sdata->s_spar_map[j])
 200                                                 {
 201                                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 202                                                         mapEntry = st->mapEntry[l];
 203                                                         mapEntry.origLocation = cpu_to_le32(packet);
 204                                                         memmove(&st->mapEntry[k+1], &st->mapEntry[k], (l-k)*sizeof(struct sparingEntry));
 205                                                         st->mapEntry[k] = mapEntry;
 206                                                         udf_update_tag((char *)st, sizeof(struct sparingTable) + st->reallocationTableLen * sizeof(struct sparingEntry));
 207                                                         mark_buffer_dirty(sdata->s_spar_map[j]);
 208                                                 }
 209                                         }
 210                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 211                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 212                                         return 0;
 213                                 }
 214                         }
 215                         return 1;
 216                 }
 217         }
 218         if (i == UDF_SB_NUMPARTS(sb))
 219         {
 220                 /* outside of partitions */
 221                 /* for now, fail =) */
 222                 return 1;
 223         }
 224
 225         return 0;
 226 }