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