fs/hfsplus/dir.c

   1 /*
   2  *  linux/fs/hfsplus/dir.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer ([email protected])
   6  * (C) 2003 Ardis Technologies <[email protected]>
   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                                      struct nameidata *nd)
  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                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 154                         fd.entrylength);
 155                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 156                         printk(KERN_ERR "hfs: bad catalog folder thread\n");
 157                         err = -EIO;
 158                         goto out;
 159                 }
 160                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 161                         printk(KERN_ERR "hfs: truncated catalog thread\n");
 162                         err = -EIO;
 163                         goto out;
 164                 }
 165                 if (filldir(dirent, "..", 2, 1,
 166                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 167                         goto out;
 168                 filp->f_pos++;
 169                 /* fall through */
 170         default:
 171                 if (filp->f_pos >= inode->i_size)
 172                         goto out;
 173                 err = hfs_brec_goto(&fd, filp->f_pos - 1);
 174                 if (err)
 175                         goto out;
 176         }
 177
 178         for (;;) {
 179                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 180                         printk(KERN_ERR "hfs: walked past end of dir\n");
 181                         err = -EIO;
 182                         goto out;
 183                 }
 184                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 185                         fd.entrylength);
 186                 type = be16_to_cpu(entry.type);
 187                 len = HFSPLUS_MAX_STRLEN;
 188                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 189                 if (err)
 190                         goto out;
 191                 if (type == HFSPLUS_FOLDER) {
 192                         if (fd.entrylength <
 193                                         sizeof(struct hfsplus_cat_folder)) {
 194                                 printk(KERN_ERR "hfs: small dir entry\n");
 195                                 err = -EIO;
 196                                 goto out;
 197                         }
 198                         if (HFSPLUS_SB(sb)->hidden_dir &&
 199                             HFSPLUS_SB(sb)->hidden_dir->i_ino ==
 200                                         be32_to_cpu(entry.folder.id))
 201                                 goto next;
 202                         if (filldir(dirent, strbuf, len, filp->f_pos,
 203                                     be32_to_cpu(entry.folder.id), DT_DIR))
 204                                 break;
 205                 } else if (type == HFSPLUS_FILE) {
 206                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 207                                 printk(KERN_ERR "hfs: small file entry\n");
 208                                 err = -EIO;
 209                                 goto out;
 210                         }
 211                         if (filldir(dirent, strbuf, len, filp->f_pos,
 212                                     be32_to_cpu(entry.file.id), DT_REG))
 213                                 break;
 214                 } else {
 215                         printk(KERN_ERR "hfs: bad catalog entry type\n");
 216                         err = -EIO;
 217                         goto out;
 218                 }
 219 next:
 220                 filp->f_pos++;
 221                 if (filp->f_pos >= inode->i_size)
 222                         goto out;
 223                 err = hfs_brec_goto(&fd, 1);
 224                 if (err)
 225                         goto out;
 226         }
 227         rd = filp->private_data;
 228         if (!rd) {
 229                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 230                 if (!rd) {
 231                         err = -ENOMEM;
 232                         goto out;
 233                 }
 234                 filp->private_data = rd;
 235                 rd->file = filp;
 236                 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
 237         }
 238         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 239 out:
 240         hfs_find_exit(&fd);
 241         return err;
 242 }
 243
 244 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 245 {
 246         struct hfsplus_readdir_data *rd = file->private_data;
 247         if (rd) {
 248                 mutex_lock(&inode->i_mutex);
 249                 list_del(&rd->list);
 250                 mutex_unlock(&inode->i_mutex);
 251                 kfree(rd);
 252         }
 253         return 0;
 254 }
 255
 256 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 257                         struct dentry *dst_dentry)
 258 {
 259         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 260         struct inode *inode = src_dentry->d_inode;
 261         struct inode *src_dir = src_dentry->d_parent->d_inode;
 262         struct qstr str;
 263         char name[32];
 264         u32 cnid, id;
 265         int res;
 266
 267         if (HFSPLUS_IS_RSRC(inode))
 268                 return -EPERM;
 269         if (!S_ISREG(inode->i_mode))
 270                 return -EPERM;
 271
 272         mutex_lock(&sbi->vh_mutex);
 273         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 274                 for (;;) {
 275                         get_random_bytes(&id, sizeof(cnid));
 276                         id &= 0x3fffffff;
 277                         str.name = name;
 278                         str.len = sprintf(name, "iNode%d", id);
 279                         res = hfsplus_rename_cat(inode->i_ino,
 280                                                  src_dir, &src_dentry->d_name,
 281                                                  sbi->hidden_dir, &str);
 282                         if (!res)
 283                                 break;
 284                         if (res != -EEXIST)
 285                                 goto out;
 286                 }
 287                 HFSPLUS_I(inode)->linkid = id;
 288                 cnid = sbi->next_cnid++;
 289                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 290                 res = hfsplus_create_cat(cnid, src_dir,
 291                         &src_dentry->d_name, inode);
 292                 if (res)
 293                         /* panic? */
 294                         goto out;
 295                 sbi->file_count++;
 296         }
 297         cnid = sbi->next_cnid++;
 298         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 299         if (res)
 300                 goto out;
 301
 302         inc_nlink(inode);
 303         hfsplus_instantiate(dst_dentry, inode, cnid);
 304         ihold(inode);
 305         inode->i_ctime = CURRENT_TIME_SEC;
 306         mark_inode_dirty(inode);
 307         sbi->file_count++;
 308         dst_dir->i_sb->s_dirt = 1;
 309 out:
 310         mutex_unlock(&sbi->vh_mutex);
 311         return res;
 312 }
 313
 314 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 315 {
 316         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 317         struct inode *inode = dentry->d_inode;
 318         struct qstr str;
 319         char name[32];
 320         u32 cnid;
 321         int res;
 322
 323         if (HFSPLUS_IS_RSRC(inode))
 324                 return -EPERM;
 325
 326         mutex_lock(&sbi->vh_mutex);
 327         cnid = (u32)(unsigned long)dentry->d_fsdata;
 328         if (inode->i_ino == cnid &&
 329             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 330                 str.name = name;
 331                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 332                 res = hfsplus_rename_cat(inode->i_ino,
 333                                          dir, &dentry->d_name,
 334                                          sbi->hidden_dir, &str);
 335                 if (!res) {
 336                         inode->i_flags |= S_DEAD;
 337                         drop_nlink(inode);
 338                 }
 339                 goto out;
 340         }
 341         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 342         if (res)
 343                 goto out;
 344
 345         if (inode->i_nlink > 0)
 346                 drop_nlink(inode);
 347         if (inode->i_ino == cnid)
 348                 clear_nlink(inode);
 349         if (!inode->i_nlink) {
 350                 if (inode->i_ino != cnid) {
 351                         sbi->file_count--;
 352                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 353                                 res = hfsplus_delete_cat(inode->i_ino,
 354                                                          sbi->hidden_dir,
 355                                                          NULL);
 356                                 if (!res)
 357                                         hfsplus_delete_inode(inode);
 358                         } else
 359                                 inode->i_flags |= S_DEAD;
 360                 } else
 361                         hfsplus_delete_inode(inode);
 362         } else
 363                 sbi->file_count--;
 364         inode->i_ctime = CURRENT_TIME_SEC;
 365         mark_inode_dirty(inode);
 366 out:
 367         mutex_unlock(&sbi->vh_mutex);
 368         return res;
 369 }
 370
 371 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 372 {
 373         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 374         struct inode *inode = dentry->d_inode;
 375         int res;
 376
 377         if (inode->i_size != 2)
 378                 return -ENOTEMPTY;
 379
 380         mutex_lock(&sbi->vh_mutex);
 381         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 382         if (res)
 383                 goto out;
 384         clear_nlink(inode);
 385         inode->i_ctime = CURRENT_TIME_SEC;
 386         hfsplus_delete_inode(inode);
 387         mark_inode_dirty(inode);
 388 out:
 389         mutex_unlock(&sbi->vh_mutex);
 390         return res;
 391 }
 392
 393 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 394                            const char *symname)
 395 {
 396         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 397         struct inode *inode;
 398         int res = -ENOSPC;
 399
 400         mutex_lock(&sbi->vh_mutex);
 401         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 402         if (!inode)
 403                 goto out;
 404
 405         res = page_symlink(inode, symname, strlen(symname) + 1);
 406         if (res)
 407                 goto out_err;
 408
 409         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 410         if (res)
 411                 goto out_err;
 412
 413         hfsplus_instantiate(dentry, inode, inode->i_ino);
 414         mark_inode_dirty(inode);
 415         goto out;
 416
 417 out_err:
 418         inode->i_nlink = 0;
 419         hfsplus_delete_inode(inode);
 420         iput(inode);
 421 out:
 422         mutex_unlock(&sbi->vh_mutex);
 423         return res;
 424 }
 425
 426 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 427                          int mode, dev_t rdev)
 428 {
 429         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 430         struct inode *inode;
 431         int res = -ENOSPC;
 432
 433         mutex_lock(&sbi->vh_mutex);
 434         inode = hfsplus_new_inode(dir->i_sb, mode);
 435         if (!inode)
 436                 goto out;
 437
 438         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 439                 init_special_inode(inode, mode, rdev);
 440
 441         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 442         if (res) {
 443                 inode->i_nlink = 0;
 444                 hfsplus_delete_inode(inode);
 445                 iput(inode);
 446                 goto out;
 447         }
 448
 449         hfsplus_instantiate(dentry, inode, inode->i_ino);
 450         mark_inode_dirty(inode);
 451 out:
 452         mutex_unlock(&sbi->vh_mutex);
 453         return res;
 454 }
 455
 456 static int hfsplus_create(struct inode *dir, struct dentry *dentry, int mode,
 457                           struct nameidata *nd)
 458 {
 459         return hfsplus_mknod(dir, dentry, mode, 0);
 460 }
 461
 462 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 463 {
 464         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 465 }
 466
 467 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 468                           struct inode *new_dir, struct dentry *new_dentry)
 469 {
 470         int res;
 471
 472         /* Unlink destination if it already exists */
 473         if (new_dentry->d_inode) {
 474                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 475                         res = hfsplus_rmdir(new_dir, new_dentry);
 476                 else
 477                         res = hfsplus_unlink(new_dir, new_dentry);
 478                 if (res)
 479                         return res;
 480         }
 481
 482         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 483                                  old_dir, &old_dentry->d_name,
 484                                  new_dir, &new_dentry->d_name);
 485         if (!res)
 486                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 487         return res;
 488 }
 489
 490 const struct inode_operations hfsplus_dir_inode_operations = {
 491         .lookup         = hfsplus_lookup,
 492         .create         = hfsplus_create,
 493         .link           = hfsplus_link,
 494         .unlink         = hfsplus_unlink,
 495         .mkdir          = hfsplus_mkdir,
 496         .rmdir          = hfsplus_rmdir,
 497         .symlink        = hfsplus_symlink,
 498         .mknod          = hfsplus_mknod,
 499         .rename         = hfsplus_rename,
 500 };
 501
 502 const struct file_operations hfsplus_dir_operations = {
 503         .fsync          = hfsplus_file_fsync,
 504         .read           = generic_read_dir,
 505         .readdir        = hfsplus_readdir,
 506         .unlocked_ioctl = hfsplus_ioctl,
 507         .llseek         = generic_file_llseek,
 508         .release        = hfsplus_dir_release,
 509 };