fs/hfsplus/dir.c

   1 /*
   2  *  linux/fs/hfsplus/dir.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer (flar@allandria.com)
   6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   7  *
   8  * Handling of directories
   9  */
  10
  11 #include <linux/errno.h>
  12 #include <linux/fs.h>
  13 #include <linux/slab.h>
  14 #include <linux/random.h>
  15
  16 #include "hfsplus_fs.h"
  17 #include "hfsplus_raw.h"
  18
  19 static inline void hfsplus_instantiate(struct dentry *dentry,
  20                                        struct inode *inode, u32 cnid)
  21 {
  22         dentry->d_fsdata = (void *)(unsigned long)cnid;
  23         d_instantiate(dentry, inode);
  24 }
  25
  26 /* Find the entry inside dir named dentry->d_name */
  27 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
  28                                      unsigned int flags)
  29 {
  30         struct inode *inode = NULL;
  31         struct hfs_find_data fd;
  32         struct super_block *sb;
  33         hfsplus_cat_entry entry;
  34         int err;
  35         u32 cnid, linkid = 0;
  36         u16 type;
  37
  38         sb = dir->i_sb;
  39
  40         dentry->d_fsdata = NULL;
  41         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
  42         if (err)
  43                 return ERR_PTR(err);
  44         hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
  45 again:
  46         err = hfs_brec_read(&fd, &entry, sizeof(entry));
  47         if (err) {
  48                 if (err == -ENOENT) {
  49                         hfs_find_exit(&fd);
  50                         /* No such entry */
  51                         inode = NULL;
  52                         goto out;
  53                 }
  54                 goto fail;
  55         }
  56         type = be16_to_cpu(entry.type);
  57         if (type == HFSPLUS_FOLDER) {
  58                 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
  59                         err = -EIO;
  60                         goto fail;
  61                 }
  62                 cnid = be32_to_cpu(entry.folder.id);
  63                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  64         } else if (type == HFSPLUS_FILE) {
  65                 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
  66                         err = -EIO;
  67                         goto fail;
  68                 }
  69                 cnid = be32_to_cpu(entry.file.id);
  70                 if (entry.file.user_info.fdType ==
  71                                 cpu_to_be32(HFSP_HARDLINK_TYPE) &&
  72                                 entry.file.user_info.fdCreator ==
  73                                 cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
  74                                 (entry.file.create_date ==
  75                                         HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
  76                                                 create_date ||
  77                                 entry.file.create_date ==
  78                                         HFSPLUS_I(sb->s_root->d_inode)->
  79                                                 create_date) &&
  80                                 HFSPLUS_SB(sb)->hidden_dir) {
  81                         struct qstr str;
  82                         char name[32];
  83
  84                         if (dentry->d_fsdata) {
  85                                 /*
  86                                  * We found a link pointing to another link,
  87                                  * so ignore it and treat it as regular file.
  88                                  */
  89                                 cnid = (unsigned long)dentry->d_fsdata;
  90                                 linkid = 0;
  91                         } else {
  92                                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  93                                 linkid =
  94                                         be32_to_cpu(entry.file.permissions.dev);
  95                                 str.len = sprintf(name, "iNode%d", linkid);
  96                                 str.name = name;
  97                                 hfsplus_cat_build_key(sb, fd.search_key,
  98                                         HFSPLUS_SB(sb)->hidden_dir->i_ino,
  99                                         &str);
 100                                 goto again;
 101                         }
 102                 } else if (!dentry->d_fsdata)
 103                         dentry->d_fsdata = (void *)(unsigned long)cnid;
 104         } else {
 105                 printk(KERN_ERR "hfs: invalid catalog entry type in lookup\n");
 106                 err = -EIO;
 107                 goto fail;
 108         }
 109         hfs_find_exit(&fd);
 110         inode = hfsplus_iget(dir->i_sb, cnid);
 111         if (IS_ERR(inode))
 112                 return ERR_CAST(inode);
 113         if (S_ISREG(inode->i_mode))
 114                 HFSPLUS_I(inode)->linkid = linkid;
 115 out:
 116         d_add(dentry, inode);
 117         return NULL;
 118 fail:
 119         hfs_find_exit(&fd);
 120         return ERR_PTR(err);
 121 }
 122
 123 static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
 124 {
 125         struct inode *inode = filp->f_path.dentry->d_inode;
 126         struct super_block *sb = inode->i_sb;
 127         int len, err;
 128         char strbuf[HFSPLUS_MAX_STRLEN + 1];
 129         hfsplus_cat_entry entry;
 130         struct hfs_find_data fd;
 131         struct hfsplus_readdir_data *rd;
 132         u16 type;
 133
 134         if (filp->f_pos >= inode->i_size)
 135                 return 0;
 136
 137         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
 138         if (err)
 139                 return err;
 140         hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
 141         err = hfs_brec_find(&fd);
 142         if (err)
 143                 goto out;
 144
 145         switch ((u32)filp->f_pos) {
 146         case 0:
 147                 /* This is completely artificial... */
 148                 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
 149                         goto out;
 150                 filp->f_pos++;
 151                 /* fall through */
 152         case 1:
 153                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 154                         err = -EIO;
 155                         goto out;
 156                 }
 157
 158                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 159                         fd.entrylength);
 160                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 161                         printk(KERN_ERR "hfs: bad catalog folder thread\n");
 162                         err = -EIO;
 163                         goto out;
 164                 }
 165                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 166                         printk(KERN_ERR "hfs: truncated catalog thread\n");
 167                         err = -EIO;
 168                         goto out;
 169                 }
 170                 if (filldir(dirent, "..", 2, 1,
 171                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 172                         goto out;
 173                 filp->f_pos++;
 174                 /* fall through */
 175         default:
 176                 if (filp->f_pos >= inode->i_size)
 177                         goto out;
 178                 err = hfs_brec_goto(&fd, filp->f_pos - 1);
 179                 if (err)
 180                         goto out;
 181         }
 182
 183         for (;;) {
 184                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 185                         printk(KERN_ERR "hfs: walked past end of dir\n");
 186                         err = -EIO;
 187                         goto out;
 188                 }
 189
 190                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 191                         err = -EIO;
 192                         goto out;
 193                 }
 194
 195                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 196                         fd.entrylength);
 197                 type = be16_to_cpu(entry.type);
 198                 len = HFSPLUS_MAX_STRLEN;
 199                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 200                 if (err)
 201                         goto out;
 202                 if (type == HFSPLUS_FOLDER) {
 203                         if (fd.entrylength <
 204                                         sizeof(struct hfsplus_cat_folder)) {
 205                                 printk(KERN_ERR "hfs: small dir entry\n");
 206                                 err = -EIO;
 207                                 goto out;
 208                         }
 209                         if (HFSPLUS_SB(sb)->hidden_dir &&
 210                             HFSPLUS_SB(sb)->hidden_dir->i_ino ==
 211                                         be32_to_cpu(entry.folder.id))
 212                                 goto next;
 213                         if (filldir(dirent, strbuf, len, filp->f_pos,
 214                                     be32_to_cpu(entry.folder.id), DT_DIR))
 215                                 break;
 216                 } else if (type == HFSPLUS_FILE) {
 217                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 218                                 printk(KERN_ERR "hfs: small file entry\n");
 219                                 err = -EIO;
 220                                 goto out;
 221                         }
 222                         if (filldir(dirent, strbuf, len, filp->f_pos,
 223                                     be32_to_cpu(entry.file.id), DT_REG))
 224                                 break;
 225                 } else {
 226                         printk(KERN_ERR "hfs: bad catalog entry type\n");
 227                         err = -EIO;
 228                         goto out;
 229                 }
 230 next:
 231                 filp->f_pos++;
 232                 if (filp->f_pos >= inode->i_size)
 233                         goto out;
 234                 err = hfs_brec_goto(&fd, 1);
 235                 if (err)
 236                         goto out;
 237         }
 238         rd = filp->private_data;
 239         if (!rd) {
 240                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 241                 if (!rd) {
 242                         err = -ENOMEM;
 243                         goto out;
 244                 }
 245                 filp->private_data = rd;
 246                 rd->file = filp;
 247                 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
 248         }
 249         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 250 out:
 251         hfs_find_exit(&fd);
 252         return err;
 253 }
 254
 255 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 256 {
 257         struct hfsplus_readdir_data *rd = file->private_data;
 258         if (rd) {
 259                 mutex_lock(&inode->i_mutex);
 260                 list_del(&rd->list);
 261                 mutex_unlock(&inode->i_mutex);
 262                 kfree(rd);
 263         }
 264         return 0;
 265 }
 266
 267 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 268                         struct dentry *dst_dentry)
 269 {
 270         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 271         struct inode *inode = src_dentry->d_inode;
 272         struct inode *src_dir = src_dentry->d_parent->d_inode;
 273         struct qstr str;
 274         char name[32];
 275         u32 cnid, id;
 276         int res;
 277
 278         if (HFSPLUS_IS_RSRC(inode))
 279                 return -EPERM;
 280         if (!S_ISREG(inode->i_mode))
 281                 return -EPERM;
 282
 283         mutex_lock(&sbi->vh_mutex);
 284         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 285                 for (;;) {
 286                         get_random_bytes(&id, sizeof(cnid));
 287                         id &= 0x3fffffff;
 288                         str.name = name;
 289                         str.len = sprintf(name, "iNode%d", id);
 290                         res = hfsplus_rename_cat(inode->i_ino,
 291                                                  src_dir, &src_dentry->d_name,
 292                                                  sbi->hidden_dir, &str);
 293                         if (!res)
 294                                 break;
 295                         if (res != -EEXIST)
 296                                 goto out;
 297                 }
 298                 HFSPLUS_I(inode)->linkid = id;
 299                 cnid = sbi->next_cnid++;
 300                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 301                 res = hfsplus_create_cat(cnid, src_dir,
 302                         &src_dentry->d_name, inode);
 303                 if (res)
 304                         /* panic? */
 305                         goto out;
 306                 sbi->file_count++;
 307         }
 308         cnid = sbi->next_cnid++;
 309         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 310         if (res)
 311                 goto out;
 312
 313         inc_nlink(inode);
 314         hfsplus_instantiate(dst_dentry, inode, cnid);
 315         ihold(inode);
 316         inode->i_ctime = CURRENT_TIME_SEC;
 317         mark_inode_dirty(inode);
 318         sbi->file_count++;
 319         hfsplus_mark_mdb_dirty(dst_dir->i_sb);
 320 out:
 321         mutex_unlock(&sbi->vh_mutex);
 322         return res;
 323 }
 324
 325 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 326 {
 327         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 328         struct inode *inode = dentry->d_inode;
 329         struct qstr str;
 330         char name[32];
 331         u32 cnid;
 332         int res;
 333
 334         if (HFSPLUS_IS_RSRC(inode))
 335                 return -EPERM;
 336
 337         mutex_lock(&sbi->vh_mutex);
 338         cnid = (u32)(unsigned long)dentry->d_fsdata;
 339         if (inode->i_ino == cnid &&
 340             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 341                 str.name = name;
 342                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 343                 res = hfsplus_rename_cat(inode->i_ino,
 344                                          dir, &dentry->d_name,
 345                                          sbi->hidden_dir, &str);
 346                 if (!res) {
 347                         inode->i_flags |= S_DEAD;
 348                         drop_nlink(inode);
 349                 }
 350                 goto out;
 351         }
 352         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 353         if (res)
 354                 goto out;
 355
 356         if (inode->i_nlink > 0)
 357                 drop_nlink(inode);
 358         if (inode->i_ino == cnid)
 359                 clear_nlink(inode);
 360         if (!inode->i_nlink) {
 361                 if (inode->i_ino != cnid) {
 362                         sbi->file_count--;
 363                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 364                                 res = hfsplus_delete_cat(inode->i_ino,
 365                                                          sbi->hidden_dir,
 366                                                          NULL);
 367                                 if (!res)
 368                                         hfsplus_delete_inode(inode);
 369                         } else
 370                                 inode->i_flags |= S_DEAD;
 371                 } else
 372                         hfsplus_delete_inode(inode);
 373         } else
 374                 sbi->file_count--;
 375         inode->i_ctime = CURRENT_TIME_SEC;
 376         mark_inode_dirty(inode);
 377 out:
 378         mutex_unlock(&sbi->vh_mutex);
 379         return res;
 380 }
 381
 382 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 383 {
 384         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 385         struct inode *inode = dentry->d_inode;
 386         int res;
 387
 388         if (inode->i_size != 2)
 389                 return -ENOTEMPTY;
 390
 391         mutex_lock(&sbi->vh_mutex);
 392         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 393         if (res)
 394                 goto out;
 395         clear_nlink(inode);
 396         inode->i_ctime = CURRENT_TIME_SEC;
 397         hfsplus_delete_inode(inode);
 398         mark_inode_dirty(inode);
 399 out:
 400         mutex_unlock(&sbi->vh_mutex);
 401         return res;
 402 }
 403
 404 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 405                            const char *symname)
 406 {
 407         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 408         struct inode *inode;
 409         int res = -ENOSPC;
 410
 411         mutex_lock(&sbi->vh_mutex);
 412         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 413         if (!inode)
 414                 goto out;
 415
 416         res = page_symlink(inode, symname, strlen(symname) + 1);
 417         if (res)
 418                 goto out_err;
 419
 420         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 421         if (res)
 422                 goto out_err;
 423
 424         hfsplus_instantiate(dentry, inode, inode->i_ino);
 425         mark_inode_dirty(inode);
 426         goto out;
 427
 428 out_err:
 429         clear_nlink(inode);
 430         hfsplus_delete_inode(inode);
 431         iput(inode);
 432 out:
 433         mutex_unlock(&sbi->vh_mutex);
 434         return res;
 435 }
 436
 437 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 438                          umode_t mode, dev_t rdev)
 439 {
 440         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 441         struct inode *inode;
 442         int res = -ENOSPC;
 443
 444         mutex_lock(&sbi->vh_mutex);
 445         inode = hfsplus_new_inode(dir->i_sb, mode);
 446         if (!inode)
 447                 goto out;
 448
 449         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 450                 init_special_inode(inode, mode, rdev);
 451
 452         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 453         if (res) {
 454                 clear_nlink(inode);
 455                 hfsplus_delete_inode(inode);
 456                 iput(inode);
 457                 goto out;
 458         }
 459
 460         hfsplus_instantiate(dentry, inode, inode->i_ino);
 461         mark_inode_dirty(inode);
 462 out:
 463         mutex_unlock(&sbi->vh_mutex);
 464         return res;
 465 }
 466
 467 static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 468                           bool excl)
 469 {
 470         return hfsplus_mknod(dir, dentry, mode, 0);
 471 }
 472
 473 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 474 {
 475         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 476 }
 477
 478 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 479                           struct inode *new_dir, struct dentry *new_dentry)
 480 {
 481         int res;
 482
 483         /* Unlink destination if it already exists */
 484         if (new_dentry->d_inode) {
 485                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 486                         res = hfsplus_rmdir(new_dir, new_dentry);
 487                 else
 488                         res = hfsplus_unlink(new_dir, new_dentry);
 489                 if (res)
 490                         return res;
 491         }
 492
 493         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 494                                  old_dir, &old_dentry->d_name,
 495                                  new_dir, &new_dentry->d_name);
 496         if (!res)
 497                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 498         return res;
 499 }
 500
 501 const struct inode_operations hfsplus_dir_inode_operations = {
 502         .lookup         = hfsplus_lookup,
 503         .create         = hfsplus_create,
 504         .link           = hfsplus_link,
 505         .unlink         = hfsplus_unlink,
 506         .mkdir          = hfsplus_mkdir,
 507         .rmdir          = hfsplus_rmdir,
 508         .symlink        = hfsplus_symlink,
 509         .mknod          = hfsplus_mknod,
 510         .rename         = hfsplus_rename,
 511 };
 512
 513 const struct file_operations hfsplus_dir_operations = {
 514         .fsync          = hfsplus_file_fsync,
 515         .read           = generic_read_dir,
 516         .readdir        = hfsplus_readdir,
 517         .unlocked_ioctl = hfsplus_ioctl,
 518         .llseek         = generic_file_llseek,
 519         .release        = hfsplus_dir_release,
 520 };