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/udf_fs.h>
  28 #include <linux/slab.h>
  29 #include <linux/buffer_head.h>
  30
  31 inline uint32_t udf_get_pblock(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
  32 {
  33         if (partition >= UDF_SB_NUMPARTS(sb))
  34         {
  35                 udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
  36                         block, partition, offset);
  37                 return 0xFFFFFFFF;
  38         }
  39         if (UDF_SB_PARTFUNC(sb, partition))
  40                 return UDF_SB_PARTFUNC(sb, partition)(sb, block, partition, offset);
  41         else
  42                 return UDF_SB_PARTROOT(sb, partition) + block + offset;
  43 }
  44
  45 uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
  46 {
  47         struct buffer_head *bh = NULL;
  48         uint32_t newblock;
  49         uint32_t index;
  50         uint32_t loc;
  51
  52         index = (sb->s_blocksize - UDF_SB_TYPEVIRT(sb,partition).s_start_offset) / sizeof(uint32_t);
  53
  54         if (block > UDF_SB_TYPEVIRT(sb,partition).s_num_entries)
  55         {
  56                 udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
  57                         block, UDF_SB_TYPEVIRT(sb,partition).s_num_entries);
  58                 return 0xFFFFFFFF;
  59         }
  60
  61         if (block >= index)
  62         {
  63                 block -= index;
  64                 newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
  65                 index = block % (sb->s_blocksize / sizeof(uint32_t));
  66         }
  67         else
  68         {
  69                 newblock = 0;
  70                 index = UDF_SB_TYPEVIRT(sb,partition).s_start_offset / sizeof(uint32_t) + block;
  71         }
  72
  73         loc = udf_block_map(UDF_SB_VAT(sb), newblock);
  74
  75         if (!(bh = sb_bread(sb, loc)))
  76         {
  77                 udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]\n",
  78                         sb, block, partition, loc, index);
  79                 return 0xFFFFFFFF;
  80         }
  81
  82         loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);
  83
  84         udf_release_data(bh);
  85
  86         if (UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum == partition)
  87         {
  88                 udf_debug("recursive call to udf_get_pblock!\n");
  89                 return 0xFFFFFFFF;
  90         }
  91
  92         return udf_get_pblock(sb, loc, UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum, offset);
  93 }
  94
  95 inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
  96 {
  97         return udf_get_pblock_virt15(sb, block, partition, offset);
  98 }
  99
 100 uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset)
 101 {
 102         int i;
 103         struct sparingTable *st = NULL;
 104         uint32_t packet = (block + offset) & ~(UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1);
 105
 106         for (i=0; i<4; i++)
 107         {
 108                 if (UDF_SB_TYPESPAR(sb,partition).s_spar_map[i] != NULL)
 109                 {
 110                         st = (struct sparingTable *)UDF_SB_TYPESPAR(sb,partition).s_spar_map[i]->b_data;
 111                         break;
 112                 }
 113         }
 114
 115         if (st)
 116         {
 117                 for (i=0; i<le16_to_cpu(st->reallocationTableLen); i++)
 118                 {
 119                         if (le32_to_cpu(st->mapEntry[i].origLocation) >= 0xFFFFFFF0)
 120                                 break;
 121                         else if (le32_to_cpu(st->mapEntry[i].origLocation) == packet)
 122                         {
 123                                 return le32_to_cpu(st->mapEntry[i].mappedLocation) +
 124                                         ((block + offset) & (UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1));
 125                         }
 126                         else if (le32_to_cpu(st->mapEntry[i].origLocation) > packet)
 127                                 break;
 128                 }
 129         }
 130         return UDF_SB_PARTROOT(sb,partition) + block + offset;
 131 }
 132
 133 int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
 134 {
 135         struct udf_sparing_data *sdata;
 136         struct sparingTable *st = NULL;
 137         struct sparingEntry mapEntry;
 138         uint32_t packet;
 139         int i, j, k, l;
 140
 141         for (i=0; i<UDF_SB_NUMPARTS(sb); i++)
 142         {
 143                 if (old_block > UDF_SB_PARTROOT(sb,i) &&
 144                     old_block < UDF_SB_PARTROOT(sb,i) + UDF_SB_PARTLEN(sb,i))
 145                 {
 146                         sdata = &UDF_SB_TYPESPAR(sb,i);
 147                         packet = (old_block - UDF_SB_PARTROOT(sb,i)) & ~(sdata->s_packet_len - 1);
 148
 149                         for (j=0; j<4; j++)
 150                         {
 151                                 if (UDF_SB_TYPESPAR(sb,i).s_spar_map[j] != NULL)
 152                                 {
 153                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 154                                         break;
 155                                 }
 156                         }
 157
 158                         if (!st)
 159                                 return 1;
 160
 161                         for (k=0; k<le16_to_cpu(st->reallocationTableLen); k++)
 162                         {
 163                                 if (le32_to_cpu(st->mapEntry[k].origLocation) == 0xFFFFFFFF)
 164                                 {
 165                                         for (; j<4; j++)
 166                                         {
 167                                                 if (sdata->s_spar_map[j])
 168                                                 {
 169                                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 170                                                         st->mapEntry[k].origLocation = cpu_to_le32(packet);
 171                                                         udf_update_tag((char *)st, sizeof(struct sparingTable) + le16_to_cpu(st->reallocationTableLen) * sizeof(struct sparingEntry));
 172                                                         mark_buffer_dirty(sdata->s_spar_map[j]);
 173                                                 }
 174                                         }
 175                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 176                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 177                                         return 0;
 178                                 }
 179                                 else if (le32_to_cpu(st->mapEntry[k].origLocation) == packet)
 180                                 {
 181                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 182                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 183                                         return 0;
 184                                 }
 185                                 else if (le32_to_cpu(st->mapEntry[k].origLocation) > packet)
 186                                         break;
 187                         }
 188                         for (l=k; l<le16_to_cpu(st->reallocationTableLen); l++)
 189                         {
 190                                 if (le32_to_cpu(st->mapEntry[l].origLocation) == 0xFFFFFFFF)
 191                                 {
 192                                         for (; j<4; j++)
 193                                         {
 194                                                 if (sdata->s_spar_map[j])
 195                                                 {
 196                                                         st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
 197                                                         mapEntry = st->mapEntry[l];
 198                                                         mapEntry.origLocation = cpu_to_le32(packet);
 199                                                         memmove(&st->mapEntry[k+1], &st->mapEntry[k], (l-k)*sizeof(struct sparingEntry));
 200                                                         st->mapEntry[k] = mapEntry;
 201                                                         udf_update_tag((char *)st, sizeof(struct sparingTable) + le16_to_cpu(st->reallocationTableLen) * sizeof(struct sparingEntry));
 202                                                         mark_buffer_dirty(sdata->s_spar_map[j]);
 203                                                 }
 204                                         }
 205                                         *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
 206                                                 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
 207                                         return 0;
 208                                 }
 209                         }
 210                         return 1;
 211                 }
 212         }
 213         if (i == UDF_SB_NUMPARTS(sb))
 214         {
 215                 /* outside of partitions */
 216                 /* for now, fail =) */
 217                 return 1;
 218         }
 219
 220         return 0;
 221 }