fs/udf/directory.c

   1 /*
   2  * directory.c
   3  *
   4  * PURPOSE
   5  *      Directory related functions
   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
  19 #include "udfdecl.h"
  20 #include "udf_i.h"
  21
  22 #include <linux/fs.h>
  23 #include <linux/string.h>
  24 #include <linux/buffer_head.h>
  25
  26 #if 0
  27 static uint8_t *
  28 udf_filead_read(struct inode *dir, uint8_t *tmpad, uint8_t ad_size,
  29                 kernel_lb_addr fe_loc, int *pos, int *offset,
  30                 struct buffer_head **bh, int *error)
  31 {
  32         int loffset = *offset;
  33         int block;
  34         uint8_t *ad;
  35         int remainder;
  36
  37         *error = 0;
  38
  39         ad = (uint8_t *)(*bh)->b_data + *offset;
  40         *offset += ad_size;
  41
  42         if (!ad)
  43         {
  44                 udf_release_data(*bh);
  45                 *error = 1;
  46                 return NULL;
  47         }
  48
  49         if (*offset == dir->i_sb->s_blocksize)
  50         {
  51                 udf_release_data(*bh);
  52                 block = udf_get_lb_pblock(dir->i_sb, fe_loc, ++*pos);
  53                 if (!block)
  54                         return NULL;
  55                 if (!(*bh = udf_tread(dir->i_sb, block)))
  56                         return NULL;
  57         }
  58         else if (*offset > dir->i_sb->s_blocksize)
  59         {
  60                 ad = tmpad;
  61
  62                 remainder = dir->i_sb->s_blocksize - loffset;
  63                 memcpy((uint8_t *)ad, (*bh)->b_data + loffset, remainder);
  64
  65                 udf_release_data(*bh);
  66                 block = udf_get_lb_pblock(dir->i_sb, fe_loc, ++*pos);
  67                 if (!block)
  68                         return NULL;
  69                 if (!((*bh) = udf_tread(dir->i_sb, block)))
  70                         return NULL;
  71
  72                 memcpy((uint8_t *)ad + remainder, (*bh)->b_data, ad_size - remainder);
  73                 *offset = ad_size - remainder;
  74         }
  75         return ad;
  76 }
  77 #endif
  78
  79 struct fileIdentDesc *
  80 udf_fileident_read(struct inode *dir, loff_t *nf_pos,
  81         struct udf_fileident_bh *fibh,
  82         struct fileIdentDesc *cfi,
  83         kernel_lb_addr *bloc, uint32_t *extoffset,
  84         kernel_lb_addr *eloc, uint32_t *elen,
  85         uint32_t *offset, struct buffer_head **bh)
  86 {
  87         struct fileIdentDesc *fi;
  88         int i, num, block;
  89         struct buffer_head * tmp, * bha[16];
  90
  91         fibh->soffset = fibh->eoffset;
  92
  93         if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_IN_ICB)
  94         {
  95                 fi = udf_get_fileident(UDF_I_DATA(dir) -
  96                         (UDF_I_EFE(dir) ?
  97                                 sizeof(struct extendedFileEntry) :
  98                                 sizeof(struct fileEntry)),
  99                         dir->i_sb->s_blocksize, &(fibh->eoffset));
 100
 101                 if (!fi)
 102                         return NULL;
 103
 104                 *nf_pos += ((fibh->eoffset - fibh->soffset) >> 2);
 105
 106                 memcpy((uint8_t *)cfi, (uint8_t *)fi, sizeof(struct fileIdentDesc));
 107
 108                 return fi;
 109         }
 110
 111         if (fibh->eoffset == dir->i_sb->s_blocksize)
 112         {
 113                 int lextoffset = *extoffset;
 114
 115                 if (udf_next_aext(dir, bloc, extoffset, eloc, elen, bh, 1) !=
 116                         (EXT_RECORDED_ALLOCATED >> 30))
 117                 {
 118                         return NULL;
 119                 }
 120
 121                 block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset);
 122
 123                 (*offset) ++;
 124
 125                 if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen)
 126                         *offset = 0;
 127                 else
 128                         *extoffset = lextoffset;
 129
 130                 udf_release_data(fibh->sbh);
 131                 if (!(fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block)))
 132                         return NULL;
 133                 fibh->soffset = fibh->eoffset = 0;
 134
 135                 if (!(*offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9))-1)))
 136                 {
 137                         i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
 138                         if (i+*offset > (*elen >> dir->i_sb->s_blocksize_bits))
 139                                 i = (*elen >> dir->i_sb->s_blocksize_bits)-*offset;
 140                         for (num=0; i>0; i--)
 141                         {
 142                                 block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset+i);
 143                                 tmp = udf_tgetblk(dir->i_sb, block);
 144                                 if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
 145                                         bha[num++] = tmp;
 146                                 else
 147                                         brelse(tmp);
 148                         }
 149                         if (num)
 150                         {
 151                                 ll_rw_block(READA, num, bha);
 152                                 for (i=0; i<num; i++)
 153                                         brelse(bha[i]);
 154                         }
 155                 }
 156         }
 157         else if (fibh->sbh != fibh->ebh)
 158         {
 159                 udf_release_data(fibh->sbh);
 160                 fibh->sbh = fibh->ebh;
 161         }
 162
 163         fi = udf_get_fileident(fibh->sbh->b_data, dir->i_sb->s_blocksize,
 164                 &(fibh->eoffset));
 165
 166         if (!fi)
 167                 return NULL;
 168
 169         *nf_pos += ((fibh->eoffset - fibh->soffset) >> 2);
 170
 171         if (fibh->eoffset <= dir->i_sb->s_blocksize)
 172         {
 173                 memcpy((uint8_t *)cfi, (uint8_t *)fi, sizeof(struct fileIdentDesc));
 174         }
 175         else if (fibh->eoffset > dir->i_sb->s_blocksize)
 176         {
 177                 int lextoffset = *extoffset;
 178
 179                 if (udf_next_aext(dir, bloc, extoffset, eloc, elen, bh, 1) !=
 180                         (EXT_RECORDED_ALLOCATED >> 30))
 181                 {
 182                         return NULL;
 183                 }
 184
 185                 block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset);
 186
 187                 (*offset) ++;
 188
 189                 if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen)
 190                         *offset = 0;
 191                 else
 192                         *extoffset = lextoffset;
 193
 194                 fibh->soffset -= dir->i_sb->s_blocksize;
 195                 fibh->eoffset -= dir->i_sb->s_blocksize;
 196
 197                 if (!(fibh->ebh = udf_tread(dir->i_sb, block)))
 198                         return NULL;
 199
 200                 if (sizeof(struct fileIdentDesc) > - fibh->soffset)
 201                 {
 202                         int fi_len;
 203
 204                         memcpy((uint8_t *)cfi, (uint8_t *)fi, - fibh->soffset);
 205                         memcpy((uint8_t *)cfi - fibh->soffset, fibh->ebh->b_data,
 206                                 sizeof(struct fileIdentDesc) + fibh->soffset);
 207
 208                         fi_len = (sizeof(struct fileIdentDesc) + cfi->lengthFileIdent +
 209                                 le16_to_cpu(cfi->lengthOfImpUse) + 3) & ~3;
 210
 211                         *nf_pos += ((fi_len - (fibh->eoffset - fibh->soffset)) >> 2);
 212                         fibh->eoffset = fibh->soffset + fi_len;
 213                 }
 214                 else
 215                 {
 216                         memcpy((uint8_t *)cfi, (uint8_t *)fi, sizeof(struct fileIdentDesc));
 217                 }
 218         }
 219         return fi;
 220 }
 221
 222 struct fileIdentDesc *
 223 udf_get_fileident(void * buffer, int bufsize, int * offset)
 224 {
 225         struct fileIdentDesc *fi;
 226         int lengthThisIdent;
 227         uint8_t * ptr;
 228         int padlen;
 229
 230         if ( (!buffer) || (!offset) ) {
 231                 udf_debug("invalidparms\n, buffer=%p, offset=%p\n", buffer, offset);
 232                 return NULL;
 233         }
 234
 235         ptr = buffer;
 236
 237         if ( (*offset > 0) && (*offset < bufsize) ) {
 238                 ptr += *offset;
 239         }
 240         fi=(struct fileIdentDesc *)ptr;
 241         if (le16_to_cpu(fi->descTag.tagIdent) != TAG_IDENT_FID)
 242         {
 243                 udf_debug("0x%x != TAG_IDENT_FID\n",
 244                         le16_to_cpu(fi->descTag.tagIdent));
 245                 udf_debug("offset: %u sizeof: %lu bufsize: %u\n",
 246                         *offset, (unsigned long)sizeof(struct fileIdentDesc), bufsize);
 247                 return NULL;
 248         }
 249         if ( (*offset + sizeof(struct fileIdentDesc)) > bufsize )
 250         {
 251                 lengthThisIdent = sizeof(struct fileIdentDesc);
 252         }
 253         else
 254                 lengthThisIdent = sizeof(struct fileIdentDesc) +
 255                         fi->lengthFileIdent + le16_to_cpu(fi->lengthOfImpUse);
 256
 257         /* we need to figure padding, too! */
 258         padlen = lengthThisIdent % UDF_NAME_PAD;
 259         if (padlen)
 260                 lengthThisIdent += (UDF_NAME_PAD - padlen);
 261         *offset = *offset + lengthThisIdent;
 262
 263         return fi;
 264 }
 265
 266 #if 0
 267 static extent_ad *
 268 udf_get_fileextent(void * buffer, int bufsize, int * offset)
 269 {
 270         extent_ad * ext;
 271         struct fileEntry *fe;
 272         uint8_t * ptr;
 273
 274         if ( (!buffer) || (!offset) )
 275         {
 276                 printk(KERN_ERR "udf: udf_get_fileextent() invalidparms\n");
 277                 return NULL;
 278         }
 279
 280         fe = (struct fileEntry *)buffer;
 281
 282         if ( le16_to_cpu(fe->descTag.tagIdent) != TAG_IDENT_FE )
 283         {
 284                 udf_debug("0x%x != TAG_IDENT_FE\n",
 285                         le16_to_cpu(fe->descTag.tagIdent));
 286                 return NULL;
 287         }
 288
 289         ptr=(uint8_t *)(fe->extendedAttr) + le32_to_cpu(fe->lengthExtendedAttr);
 290
 291         if ( (*offset > 0) && (*offset < le32_to_cpu(fe->lengthAllocDescs)) )
 292         {
 293                 ptr += *offset;
 294         }
 295
 296         ext = (extent_ad *)ptr;
 297
 298         *offset = *offset + sizeof(extent_ad);
 299         return ext;
 300 }
 301 #endif
 302
 303 short_ad *
 304 udf_get_fileshortad(uint8_t *ptr, int maxoffset, int *offset, int inc)
 305 {
 306         short_ad *sa;
 307
 308         if ( (!ptr) || (!offset) )
 309         {
 310                 printk(KERN_ERR "udf: udf_get_fileshortad() invalidparms\n");
 311                 return NULL;
 312         }
 313
 314         if ( (*offset < 0) || ((*offset + sizeof(short_ad)) > maxoffset) )
 315                 return NULL;
 316         else if ((sa = (short_ad *)ptr)->extLength == 0)
 317                 return NULL;
 318
 319         if (inc)
 320                 *offset += sizeof(short_ad);
 321         return sa;
 322 }
 323
 324 long_ad *
 325 udf_get_filelongad(uint8_t *ptr, int maxoffset, int * offset, int inc)
 326 {
 327         long_ad *la;
 328
 329         if ( (!ptr) || (!offset) )
 330         {
 331                 printk(KERN_ERR "udf: udf_get_filelongad() invalidparms\n");
 332                 return NULL;
 333         }
 334
 335         if ( (*offset < 0) || ((*offset + sizeof(long_ad)) > maxoffset) )
 336                 return NULL;
 337         else if ((la = (long_ad *)ptr)->extLength == 0)
 338                 return NULL;
 339
 340         if (inc)
 341                 *offset += sizeof(long_ad);
 342         return la;
 343 }