fs/udf/directory.c

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