fs/udf/partition.c

   1 /*
   2  * partition.c
   3  *
   4  * PURPOSE
   5  *      Partition handling routines for the OSTA-UDF(tm) filesystem.
   6  *
   7  * COPYRIGHT
   8  *      This file is distributed under the terms of the GNU General Public
   9  *      License (GPL). Copies of the GPL can be obtained from:
  10  *              ftp://prep.ai.mit.edu/pub/gnu/GPL
  11  *      Each contributing author retains all rights to their own work.
  12  *
  13  *  (C) 1998-2001 Ben Fennema
  14  *
  15  * HISTORY
  16  *
  17  * 12/06/98 blf  Created file.
  18  *
  19  */
  20
  21 #include "udfdecl.h"
  22 #include "udf_sb.h"
  23 #include "udf_i.h"
  24
  25 #include <linux/fs.h>
  26 #include <linux/string.h>
  27 #include <linux/mutex.h>
  28
  29 uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
  30                         uint16_t partition, uint32_t offset)
  31 {
  32         struct udf_sb_info *sbi = UDF_SB(sb);
  33         struct udf_part_map *map;
  34         if (partition >= sbi->s_partitions) {
  35                 udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
  36                           block, partition, offset);
  37                 return 0xFFFFFFFF;
  38         }
  39         map = &sbi->s_partmaps[partition];
  40         if (map->s_partition_func)
  41                 return map->s_partition_func(sb, block, partition, offset);
  42         else
  43                 return map->s_partition_root + block + offset;
  44 }
  45
  46 uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block,
  47                                uint16_t partition, uint32_t offset)
  48 {
  49         struct buffer_head *bh = NULL;
  50         uint32_t newblock;
  51         uint32_t index;
  52         uint32_t loc;
  53         struct udf_sb_info *sbi = UDF_SB(sb);
  54         struct udf_part_map *map;
  55         struct udf_virtual_data *vdata;
  56         struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode);
  57
  58         map = &sbi->s_partmaps[partition];
  59         vdata = &map->s_type_specific.s_virtual;
  60
  61         if (block > vdata->s_num_entries) {
  62                 udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
  63                           block, vdata->s_num_entries);
  64                 return 0xFFFFFFFF;
  65         }
  66
  67         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
  68                 loc = le32_to_cpu(((__le32 *)(iinfo->i_ext.i_data +
  69                         vdata->s_start_offset))[block]);
  70                 goto translate;
  71         }
  72         index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t);
  73         if (block >= index) {
  74                 block -= index;
  75                 newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
  76                 index = block % (sb->s_blocksize / sizeof(uint32_t));
  77         } else {
  78                 newblock = 0;
  79                 index = vdata->s_start_offset / sizeof(uint32_t) + block;
  80         }
  81
  82         loc = udf_block_map(sbi->s_vat_inode, newblock);
  83
  84         bh = sb_bread(sb, loc);
  85         if (!bh) {
  86                 udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]\n",
  87                           sb, block, partition, loc, index);
  88                 return 0xFFFFFFFF;
  89         }
  90
  91         loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);
  92
  93         brelse(bh);
  94
  95 translate:
  96         if (iinfo->i_location.partitionReferenceNum == partition) {
  97                 udf_debug("recursive call to udf_get_pblock!\n");
  98                 return 0xFFFFFFFF;
  99         }
 100
 101         return udf_get_pblock(sb, loc,
 102                               iinfo->i_location.partitionReferenceNum,
 103                               offset);
 104 }
 105
 106 inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block,
 107                                       uint16_t partition, uint32_t offset)
 108 {
 109         return udf_get_pblock_virt15(sb, block, partition, offset);
 110 }
 111
 112 uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block,
 113                                uint16_t partition, uint32_t offset)
 114 {
 115         int i;
 116         struct sparingTable *st = NULL;
 117         struct udf_sb_info *sbi = UDF_SB(sb);
 118         struct udf_part_map *map;
 119         uint32_t packet;
 120         struct udf_sparing_data *sdata;
 121
 122         map = &sbi->s_partmaps[partition];
 123         sdata = &map->s_type_specific.s_sparing;
 124         packet = (block + offset) & ~(sdata->s_packet_len - 1);
 125
 126         for (i = 0; i < 4; i++) {
 127                 if (sdata->s_spar_map[i] != NULL) {
 128                         st = (struct sparingTable *)
 129                                         sdata->s_spar_map[i]->b_data;
 130                         break;
 131                 }
 132         }
 133
 134         if (st) {
 135                 for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
 136                         struct sparingEntry *entry = &st->mapEntry[i];
 137                         u32 origLoc = le32_to_cpu(entry->origLocation);
 138                         if (origLoc >= 0xFFFFFFF0)
 139                                 break;
 140                         else if (origLoc == packet)
 141                                 return le32_to_cpu(entry->mappedLocation) +
 142                                         ((block + offset) &
 143                                                 (sdata->s_packet_len - 1));
 144                         else if (origLoc > packet)
 145                                 break;
 146                 }
 147         }
 148
 149         return map->s_partition_root + block + offset;
 150 }
 151
 152 int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
 153 {
 154         struct udf_sparing_data *sdata;
 155         struct sparingTable *st = NULL;
 156         struct sparingEntry mapEntry;
 157         uint32_t packet;
 158         int i, j, k, l;
 159         struct udf_sb_info *sbi = UDF_SB(sb);
 160         u16 reallocationTableLen;
 161         struct buffer_head *bh;
 162         int ret = 0;
 163
 164         mutex_lock(&sbi->s_alloc_mutex);
 165         for (i = 0; i < sbi->s_partitions; i++) {
 166                 struct udf_part_map *map = &sbi->s_partmaps[i];
 167                 if (old_block > map->s_partition_root &&
 168                     old_block < map->s_partition_root + map->s_partition_len) {
 169                         sdata = &map->s_type_specific.s_sparing;
 170                         packet = (old_block - map->s_partition_root) &
 171                                                 ~(sdata->s_packet_len - 1);
 172
 173                         for (j = 0; j < 4; j++)
 174                                 if (sdata->s_spar_map[j] != NULL) {
 175                                         st = (struct sparingTable *)
 176                                                 sdata->s_spar_map[j]->b_data;
 177                                         break;
 178                                 }
 179
 180                         if (!st) {
 181                                 ret = 1;
 182                                 goto out;
 183                         }
 184
 185                         reallocationTableLen =
 186                                         le16_to_cpu(st->reallocationTableLen);
 187                         for (k = 0; k < reallocationTableLen; k++) {
 188                                 struct sparingEntry *entry = &st->mapEntry[k];
 189                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 190
 191                                 if (origLoc == 0xFFFFFFFF) {
 192                                         for (; j < 4; j++) {
 193                                                 int len;
 194                                                 bh = sdata->s_spar_map[j];
 195                                                 if (!bh)
 196                                                         continue;
 197
 198                                                 st = (struct sparingTable *)
 199                                                                 bh->b_data;
 200                                                 entry->origLocation =
 201                                                         cpu_to_le32(packet);
 202                                                 len =
 203                                                   sizeof(struct sparingTable) +
 204                                                   reallocationTableLen *
 205                                                   sizeof(struct sparingEntry);
 206                                                 udf_update_tag((char *)st, len);
 207                                                 mark_buffer_dirty(bh);
 208                                         }
 209                                         *new_block = le32_to_cpu(
 210                                                         entry->mappedLocation) +
 211                                                      ((old_block -
 212                                                         map->s_partition_root) &
 213                                                      (sdata->s_packet_len - 1));
 214                                         ret = 0;
 215                                         goto out;
 216                                 } else if (origLoc == packet) {
 217                                         *new_block = le32_to_cpu(
 218                                                         entry->mappedLocation) +
 219                                                      ((old_block -
 220                                                         map->s_partition_root) &
 221                                                      (sdata->s_packet_len - 1));
 222                                         ret = 0;
 223                                         goto out;
 224                                 } else if (origLoc > packet)
 225                                         break;
 226                         }
 227
 228                         for (l = k; l < reallocationTableLen; l++) {
 229                                 struct sparingEntry *entry = &st->mapEntry[l];
 230                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 231
 232                                 if (origLoc != 0xFFFFFFFF)
 233                                         continue;
 234
 235                                 for (; j < 4; j++) {
 236                                         bh = sdata->s_spar_map[j];
 237                                         if (!bh)
 238                                                 continue;
 239
 240                                         st = (struct sparingTable *)bh->b_data;
 241                                         mapEntry = st->mapEntry[l];
 242                                         mapEntry.origLocation =
 243                                                         cpu_to_le32(packet);
 244                                         memmove(&st->mapEntry[k + 1],
 245                                                 &st->mapEntry[k],
 246                                                 (l - k) *
 247                                                 sizeof(struct sparingEntry));
 248                                         st->mapEntry[k] = mapEntry;
 249                                         udf_update_tag((char *)st,
 250                                                 sizeof(struct sparingTable) +
 251                                                 reallocationTableLen *
 252                                                 sizeof(struct sparingEntry));
 253                                         mark_buffer_dirty(bh);
 254                                 }
 255                                 *new_block =
 256                                         le32_to_cpu(
 257                                               st->mapEntry[k].mappedLocation) +
 258                                         ((old_block - map->s_partition_root) &
 259                                          (sdata->s_packet_len - 1));
 260                                 ret = 0;
 261                                 goto out;
 262                         }
 263
 264                         ret = 1;
 265                         goto out;
 266                 } /* if old_block */
 267         }
 268
 269         if (i == sbi->s_partitions) {
 270                 /* outside of partitions */
 271                 /* for now, fail =) */
 272                 ret = 1;
 273         }
 274
 275 out:
 276         mutex_unlock(&sbi->s_alloc_mutex);
 277         return ret;
 278 }
 279
 280 static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
 281                                         uint16_t partition, uint32_t offset)
 282 {
 283         struct super_block *sb = inode->i_sb;
 284         struct udf_part_map *map;
 285         struct kernel_lb_addr eloc;
 286         uint32_t elen;
 287         sector_t ext_offset;
 288         struct extent_position epos = {};
 289         uint32_t phyblock;
 290
 291         if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
 292                                                 (EXT_RECORDED_ALLOCATED >> 30))
 293                 phyblock = 0xFFFFFFFF;
 294         else {
 295                 map = &UDF_SB(sb)->s_partmaps[partition];
 296                 /* map to sparable/physical partition desc */
 297                 phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
 298                         map->s_partition_num, ext_offset + offset);
 299         }
 300
 301         brelse(epos.bh);
 302         return phyblock;
 303 }
 304
 305 uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
 306                                 uint16_t partition, uint32_t offset)
 307 {
 308         struct udf_sb_info *sbi = UDF_SB(sb);
 309         struct udf_part_map *map;
 310         struct udf_meta_data *mdata;
 311         uint32_t retblk;
 312         struct inode *inode;
 313
 314         udf_debug("READING from METADATA\n");
 315
 316         map = &sbi->s_partmaps[partition];
 317         mdata = &map->s_type_specific.s_metadata;
 318         inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
 319
 320         /* We shouldn't mount such media... */
 321         BUG_ON(!inode);
 322         retblk = udf_try_read_meta(inode, block, partition, offset);
 323         if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) {
 324                 udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
 325                 if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) {
 326                         mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
 327                                 mdata->s_mirror_file_loc, map->s_partition_num);
 328                         mdata->s_flags |= MF_MIRROR_FE_LOADED;
 329                 }
 330
 331                 inode = mdata->s_mirror_fe;
 332                 if (!inode)
 333                         return 0xFFFFFFFF;
 334                 retblk = udf_try_read_meta(inode, block, partition, offset);
 335         }
 336
 337         return retblk;
 338 }