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