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   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/slab.h>
  28 #include <linux/buffer_head.h>
  29
  30 inline uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
  31                                uint16_t partition, uint32_t offset)
  32 {
  33         struct udf_sb_info *sbi = UDF_SB(sb);
  34         struct udf_part_map *map;
  35         if (partition >= sbi->s_partitions) {
  36                 udf_debug("block=%d, partition=%d, offset=%d: "
  37                           "invalid partition\n", block, partition, offset);
  38                 return 0xFFFFFFFF;
  39         }
  40         map = &sbi->s_partmaps[partition];
  41         if (map->s_partition_func)
  42                 return map->s_partition_func(sb, block, partition, offset);
  43         else
  44                 return map->s_partition_root + block + offset;
  45 }
  46
  47 uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block,
  48                                uint16_t partition, uint32_t offset)
  49 {
  50         struct buffer_head *bh = NULL;
  51         uint32_t newblock;
  52         uint32_t index;
  53         uint32_t loc;
  54         struct udf_sb_info *sbi = UDF_SB(sb);
  55         struct udf_part_map *map;
  56         struct udf_virtual_data *vdata;
  57         struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode);
  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 "
  64                           "(%d max %d)\n", 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_ext.i_data)[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
 163         for (i = 0; i < sbi->s_partitions; i++) {
 164                 struct udf_part_map *map = &sbi->s_partmaps[i];
 165                 if (old_block > map->s_partition_root &&
 166                     old_block < map->s_partition_root + map->s_partition_len) {
 167                         sdata = &map->s_type_specific.s_sparing;
 168                         packet = (old_block - map->s_partition_root) &
 169                                                 ~(sdata->s_packet_len - 1);
 170
 171                         for (j = 0; j < 4; j++)
 172                                 if (sdata->s_spar_map[j] != NULL) {
 173                                         st = (struct sparingTable *)
 174                                                 sdata->s_spar_map[j]->b_data;
 175                                         break;
 176                                 }
 177
 178                         if (!st)
 179                                 return 1;
 180
 181                         reallocationTableLen =
 182                                         le16_to_cpu(st->reallocationTableLen);
 183                         for (k = 0; k < reallocationTableLen; k++) {
 184                                 struct sparingEntry *entry = &st->mapEntry[k];
 185                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 186
 187                                 if (origLoc == 0xFFFFFFFF) {
 188                                         for (; j < 4; j++) {
 189                                                 int len;
 190                                                 bh = sdata->s_spar_map[j];
 191                                                 if (!bh)
 192                                                         continue;
 193
 194                                                 st = (struct sparingTable *)
 195                                                                 bh->b_data;
 196                                                 entry->origLocation =
 197                                                         cpu_to_le32(packet);
 198                                                 len =
 199                                                   sizeof(struct sparingTable) +
 200                                                   reallocationTableLen *
 201                                                   sizeof(struct sparingEntry);
 202                                                 udf_update_tag((char *)st, len);
 203                                                 mark_buffer_dirty(bh);
 204                                         }
 205                                         *new_block = le32_to_cpu(
 206                                                         entry->mappedLocation) +
 207                                                      ((old_block -
 208                                                         map->s_partition_root) &
 209                                                      (sdata->s_packet_len - 1));
 210                                         return 0;
 211                                 } else if (origLoc == packet) {
 212                                         *new_block = le32_to_cpu(
 213                                                         entry->mappedLocation) +
 214                                                      ((old_block -
 215                                                         map->s_partition_root) &
 216                                                      (sdata->s_packet_len - 1));
 217                                         return 0;
 218                                 } else if (origLoc > packet)
 219                                         break;
 220                         }
 221
 222                         for (l = k; l < reallocationTableLen; l++) {
 223                                 struct sparingEntry *entry = &st->mapEntry[l];
 224                                 u32 origLoc = le32_to_cpu(entry->origLocation);
 225
 226                                 if (origLoc != 0xFFFFFFFF)
 227                                         continue;
 228
 229                                 for (; j < 4; j++) {
 230                                         bh = sdata->s_spar_map[j];
 231                                         if (!bh)
 232                                                 continue;
 233
 234                                         st = (struct sparingTable *)bh->b_data;
 235                                         mapEntry = st->mapEntry[l];
 236                                         mapEntry.origLocation =
 237                                                         cpu_to_le32(packet);
 238                                         memmove(&st->mapEntry[k + 1],
 239                                                 &st->mapEntry[k],
 240                                                 (l - k) *
 241                                                 sizeof(struct sparingEntry));
 242                                         st->mapEntry[k] = mapEntry;
 243                                         udf_update_tag((char *)st,
 244                                                 sizeof(struct sparingTable) +
 245                                                 reallocationTableLen *
 246                                                 sizeof(struct sparingEntry));
 247                                         mark_buffer_dirty(bh);
 248                                 }
 249                                 *new_block =
 250                                         le32_to_cpu(
 251                                               st->mapEntry[k].mappedLocation) +
 252                                         ((old_block - map->s_partition_root) &
 253                                          (sdata->s_packet_len - 1));
 254                                 return 0;
 255                         }
 256
 257                         return 1;
 258                 } /* if old_block */
 259         }
 260
 261         if (i == sbi->s_partitions) {
 262                 /* outside of partitions */
 263                 /* for now, fail =) */
 264                 return 1;
 265         }
 266
 267         return 0;
 268 }
 269
 270 static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
 271                                         uint16_t partition, uint32_t offset)
 272 {
 273         struct super_block *sb = inode->i_sb;
 274         struct udf_part_map *map;
 275         kernel_lb_addr eloc;
 276         uint32_t elen;
 277         sector_t ext_offset;
 278         struct extent_position epos = {};
 279         uint32_t phyblock;
 280
 281         if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
 282                                                 (EXT_RECORDED_ALLOCATED >> 30))
 283                 phyblock = 0xFFFFFFFF;
 284         else {
 285                 map = &UDF_SB(sb)->s_partmaps[partition];
 286                 /* map to sparable/physical partition desc */
 287                 phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
 288                         map->s_partition_num, ext_offset + offset);
 289         }
 290
 291         brelse(epos.bh);
 292         return phyblock;
 293 }
 294
 295 uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
 296                                 uint16_t partition, uint32_t offset)
 297 {
 298         struct udf_sb_info *sbi = UDF_SB(sb);
 299         struct udf_part_map *map;
 300         struct udf_meta_data *mdata;
 301         uint32_t retblk;
 302         struct inode *inode;
 303
 304         udf_debug("READING from METADATA\n");
 305
 306         map = &sbi->s_partmaps[partition];
 307         mdata = &map->s_type_specific.s_metadata;
 308         inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
 309
 310         /* We shouldn't mount such media... */
 311         BUG_ON(!inode);
 312         retblk = udf_try_read_meta(inode, block, partition, offset);
 313         if (retblk == 0xFFFFFFFF) {
 314                 udf_warning(sb, __func__, "error reading from METADATA, "
 315                         "trying to read from MIRROR");
 316                 inode = mdata->s_mirror_fe;
 317                 if (!inode)
 318                         return 0xFFFFFFFF;
 319                 retblk = udf_try_read_meta(inode, block, partition, offset);
 320         }
 321
 322         return retblk;
 323 }