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