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