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