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=%u, partition=%u, offset=%u: 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         int err;
  58
  59         map = &sbi->s_partmaps[partition];
  60         vdata = &map->s_type_specific.s_virtual;
  61
  62         if (block > vdata->s_num_entries) {
  63                 udf_debug("Trying to access block beyond end of VAT (%u max %u)\n",
  64                           block, vdata->s_num_entries);
  65                 return 0xFFFFFFFF;
  66         }
  67
  68         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
  69                 loc = le32_to_cpu(((__le32 *)(iinfo->i_data +
  70                         vdata->s_start_offset))[block]);
  71                 goto translate;
  72         }
  73         index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t);
  74         if (block >= index) {
  75                 block -= index;
  76                 newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
  77                 index = block % (sb->s_blocksize / sizeof(uint32_t));
  78         } else {
  79                 newblock = 0;
  80                 index = vdata->s_start_offset / sizeof(uint32_t) + block;
  81         }
  82
  83         bh = udf_bread(sbi->s_vat_inode, newblock, 0, &err);
  84         if (!bh) {
  85                 udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%u,%u)\n",
  86                           sb, block, partition);
  87                 return 0xFFFFFFFF;
  88         }
  89
  90         loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);
  91
  92         brelse(bh);
  93
  94 translate:
  95         if (iinfo->i_location.partitionReferenceNum == partition) {
  96                 udf_debug("recursive call to udf_get_pblock!\n");
  97                 return 0xFFFFFFFF;
  98         }
  99
 100         return udf_get_pblock(sb, loc,
 101                               iinfo->i_location.partitionReferenceNum,
 102                               offset);
 103 }
 104
 105 inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block,
 106                                       uint16_t partition, uint32_t offset)
 107 {
 108         return udf_get_pblock_virt15(sb, block, partition, offset);
 109 }
 110
 111 uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block,
 112                                uint16_t partition, uint32_t offset)
 113 {
 114         int i;
 115         struct sparingTable *st = NULL;
 116         struct udf_sb_info *sbi = UDF_SB(sb);
 117         struct udf_part_map *map;
 118         uint32_t packet;
 119         struct udf_sparing_data *sdata;
 120
 121         map = &sbi->s_partmaps[partition];
 122         sdata = &map->s_type_specific.s_sparing;
 123         packet = (block + offset) & ~(sdata->s_packet_len - 1);
 124
 125         for (i = 0; i < 4; i++) {
 126                 if (sdata->s_spar_map[i] != NULL) {
 127                         st = (struct sparingTable *)
 128                                         sdata->s_spar_map[i]->b_data;
 129                         break;
 130                 }
 131         }
 132
 133         if (st) {
 134                 for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
 135                         struct sparingEntry *entry = &st->mapEntry[i];
 136                         u32 origLoc = le32_to_cpu(entry->origLocation);
 137                         if (origLoc >= 0xFFFFFFF0)
 138                                 break;
 139                         else if (origLoc == packet)
 140                                 return le32_to_cpu(entry->mappedLocation) +
 141                                         ((block + offset) &
 142                                                 (sdata->s_packet_len - 1));
 143                         else if (origLoc > packet)
 144                                 break;
 145                 }
 146         }
 147
 148         return map->s_partition_root + block + offset;
 149 }
 150
 151 int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
 152 {
 153         struct udf_sparing_data *sdata;
 154         struct sparingTable *st = NULL;
 155         struct sparingEntry mapEntry;
 156         uint32_t packet;
 157         int i, j, k, l;
 158         struct udf_sb_info *sbi = UDF_SB(sb);
 159         u16 reallocationTableLen;
 160         struct buffer_head *bh;
 161         int ret = 0;
 162
 163         mutex_lock(&sbi->s_alloc_mutex);
 164         for (i = 0; i < sbi->s_partitions; i++) {
 165                 struct udf_part_map *map = &sbi->s_partmaps[i];
 166                 if (old_block > map->s_partition_root &&
 167                     old_block < map->s_partition_root + map->s_partition_len) {
 168                         sdata = &map->s_type_specific.s_sparing;
 169                         packet = (old_block - map->s_partition_root) &
 170                                                 ~(sdata->s_packet_len - 1);
 171
 172                         for (j = 0; j < 4; j++)
 173                                 if (sdata->s_spar_map[j] != NULL) {
 174                                         st = (struct sparingTable *)
 175                                                 sdata->s_spar_map[j]->b_data;
 176                                         break;
 177                                 }
 178
 179                         if (!st) {
 180                                 ret = 1;
 181                                 goto out;
 182                         }
 183
 184                         reallocationTableLen =
 185                                         le16_to_cpu(st->reallocationTableLen);
 186                         for (k = 0; k < reallocationTableLen; k++) {
 187                                 struct sparingEntry *entry = &st->mapEntry[k];
 188                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 189
 190                                 if (origLoc == 0xFFFFFFFF) {
 191                                         for (; j < 4; j++) {
 192                                                 int len;
 193                                                 bh = sdata->s_spar_map[j];
 194                                                 if (!bh)
 195                                                         continue;
 196
 197                                                 st = (struct sparingTable *)
 198                                                                 bh->b_data;
 199                                                 entry->origLocation =
 200                                                         cpu_to_le32(packet);
 201                                                 len =
 202                                                   sizeof(struct sparingTable) +
 203                                                   reallocationTableLen *
 204                                                   sizeof(struct sparingEntry);
 205                                                 udf_update_tag((char *)st, len);
 206                                                 mark_buffer_dirty(bh);
 207                                         }
 208                                         *new_block = le32_to_cpu(
 209                                                         entry->mappedLocation) +
 210                                                      ((old_block -
 211                                                         map->s_partition_root) &
 212                                                      (sdata->s_packet_len - 1));
 213                                         ret = 0;
 214                                         goto out;
 215                                 } else if (origLoc == packet) {
 216                                         *new_block = le32_to_cpu(
 217                                                         entry->mappedLocation) +
 218                                                      ((old_block -
 219                                                         map->s_partition_root) &
 220                                                      (sdata->s_packet_len - 1));
 221                                         ret = 0;
 222                                         goto out;
 223                                 } else if (origLoc > packet)
 224                                         break;
 225                         }
 226
 227                         for (l = k; l < reallocationTableLen; l++) {
 228                                 struct sparingEntry *entry = &st->mapEntry[l];
 229                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 230
 231                                 if (origLoc != 0xFFFFFFFF)
 232                                         continue;
 233
 234                                 for (; j < 4; j++) {
 235                                         bh = sdata->s_spar_map[j];
 236                                         if (!bh)
 237                                                 continue;
 238
 239                                         st = (struct sparingTable *)bh->b_data;
 240                                         mapEntry = st->mapEntry[l];
 241                                         mapEntry.origLocation =
 242                                                         cpu_to_le32(packet);
 243                                         memmove(&st->mapEntry[k + 1],
 244                                                 &st->mapEntry[k],
 245                                                 (l - k) *
 246                                                 sizeof(struct sparingEntry));
 247                                         st->mapEntry[k] = mapEntry;
 248                                         udf_update_tag((char *)st,
 249                                                 sizeof(struct sparingTable) +
 250                                                 reallocationTableLen *
 251                                                 sizeof(struct sparingEntry));
 252                                         mark_buffer_dirty(bh);
 253                                 }
 254                                 *new_block =
 255                                         le32_to_cpu(
 256                                               st->mapEntry[k].mappedLocation) +
 257                                         ((old_block - map->s_partition_root) &
 258                                          (sdata->s_packet_len - 1));
 259                                 ret = 0;
 260                                 goto out;
 261                         }
 262
 263                         ret = 1;
 264                         goto out;
 265                 } /* if old_block */
 266         }
 267
 268         if (i == sbi->s_partitions) {
 269                 /* outside of partitions */
 270                 /* for now, fail =) */
 271                 ret = 1;
 272         }
 273
 274 out:
 275         mutex_unlock(&sbi->s_alloc_mutex);
 276         return ret;
 277 }
 278
 279 static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
 280                                         uint16_t partition, uint32_t offset)
 281 {
 282         struct super_block *sb = inode->i_sb;
 283         struct udf_part_map *map;
 284         struct kernel_lb_addr eloc;
 285         uint32_t elen;
 286         sector_t ext_offset;
 287         struct extent_position epos = {};
 288         uint32_t phyblock;
 289
 290         if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
 291                                                 (EXT_RECORDED_ALLOCATED >> 30))
 292                 phyblock = 0xFFFFFFFF;
 293         else {
 294                 map = &UDF_SB(sb)->s_partmaps[partition];
 295                 /* map to sparable/physical partition desc */
 296                 phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
 297                         map->s_type_specific.s_metadata.s_phys_partition_ref,
 298                         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         if (!inode)
 321                 return 0xFFFFFFFF;
 322
 323         retblk = udf_try_read_meta(inode, block, partition, offset);
 324         if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) {
 325                 udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
 326                 if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) {
 327                         mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
 328                                 mdata->s_mirror_file_loc,
 329                                 mdata->s_phys_partition_ref);
 330                         if (IS_ERR(mdata->s_mirror_fe))
 331                                 mdata->s_mirror_fe = NULL;
 332                         mdata->s_flags |= MF_MIRROR_FE_LOADED;
 333                 }
 334
 335                 inode = mdata->s_mirror_fe;
 336                 if (!inode)
 337                         return 0xFFFFFFFF;
 338                 retblk = udf_try_read_meta(inode, block, partition, offset);
 339         }
 340
 341         return retblk;
 342 }