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)->dev = 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
 256         mutex_lock(&sbi->vh_mutex);
 257         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 258                 for (;;) {
 259                         get_random_bytes(&id, sizeof(cnid));
 260                         id &= 0x3fffffff;
 261                         str.name = name;
 262                         str.len = sprintf(name, "iNode%d", id);
 263                         res = hfsplus_rename_cat(inode->i_ino,
 264                                                  src_dir, &src_dentry->d_name,
 265                                                  sbi->hidden_dir, &str);
 266                         if (!res)
 267                                 break;
 268                         if (res != -EEXIST)
 269                                 goto out;
 270                 }
 271                 HFSPLUS_I(inode)->dev = id;
 272                 cnid = sbi->next_cnid++;
 273                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 274                 res = hfsplus_create_cat(cnid, src_dir, &src_dentry->d_name, inode);
 275                 if (res)
 276                         /* panic? */
 277                         goto out;
 278                 sbi->file_count++;
 279         }
 280         cnid = sbi->next_cnid++;
 281         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 282         if (res)
 283                 goto out;
 284
 285         inc_nlink(inode);
 286         hfsplus_instantiate(dst_dentry, inode, cnid);
 287         atomic_inc(&inode->i_count);
 288         inode->i_ctime = CURRENT_TIME_SEC;
 289         mark_inode_dirty(inode);
 290         sbi->file_count++;
 291         dst_dir->i_sb->s_dirt = 1;
 292 out:
 293         mutex_unlock(&sbi->vh_mutex);
 294         return res;
 295 }
 296
 297 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 298 {
 299         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 300         struct inode *inode = dentry->d_inode;
 301         struct qstr str;
 302         char name[32];
 303         u32 cnid;
 304         int res;
 305
 306         if (HFSPLUS_IS_RSRC(inode))
 307                 return -EPERM;
 308
 309         mutex_lock(&sbi->vh_mutex);
 310         cnid = (u32)(unsigned long)dentry->d_fsdata;
 311         if (inode->i_ino == cnid &&
 312             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 313                 str.name = name;
 314                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 315                 res = hfsplus_rename_cat(inode->i_ino,
 316                                          dir, &dentry->d_name,
 317                                          sbi->hidden_dir, &str);
 318                 if (!res)
 319                         inode->i_flags |= S_DEAD;
 320                 goto out;
 321         }
 322         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 323         if (res)
 324                 goto out;
 325
 326         if (inode->i_nlink > 0)
 327                 drop_nlink(inode);
 328         if (inode->i_ino == cnid)
 329                 clear_nlink(inode);
 330         if (!inode->i_nlink) {
 331                 if (inode->i_ino != cnid) {
 332                         sbi->file_count--;
 333                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 334                                 res = hfsplus_delete_cat(inode->i_ino,
 335                                                          sbi->hidden_dir,
 336                                                          NULL);
 337                                 if (!res)
 338                                         hfsplus_delete_inode(inode);
 339                         } else
 340                                 inode->i_flags |= S_DEAD;
 341                 } else
 342                         hfsplus_delete_inode(inode);
 343         } else
 344                 sbi->file_count--;
 345         inode->i_ctime = CURRENT_TIME_SEC;
 346         mark_inode_dirty(inode);
 347 out:
 348         mutex_unlock(&sbi->vh_mutex);
 349         return res;
 350 }
 351
 352 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 353 {
 354         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 355         struct inode *inode = dentry->d_inode;
 356         int res;
 357
 358         if (inode->i_size != 2)
 359                 return -ENOTEMPTY;
 360
 361         mutex_lock(&sbi->vh_mutex);
 362         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 363         if (res)
 364                 goto out;
 365         clear_nlink(inode);
 366         inode->i_ctime = CURRENT_TIME_SEC;
 367         hfsplus_delete_inode(inode);
 368         mark_inode_dirty(inode);
 369 out:
 370         mutex_unlock(&sbi->vh_mutex);
 371         return res;
 372 }
 373
 374 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 375                            const char *symname)
 376 {
 377         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 378         struct inode *inode;
 379         int res = -ENOSPC;
 380
 381         mutex_lock(&sbi->vh_mutex);
 382         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 383         if (!inode)
 384                 goto out;
 385
 386         res = page_symlink(inode, symname, strlen(symname) + 1);
 387         if (res)
 388                 goto out_err;
 389
 390         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 391         if (res)
 392                 goto out_err;
 393
 394         hfsplus_instantiate(dentry, inode, inode->i_ino);
 395         mark_inode_dirty(inode);
 396         goto out;
 397
 398 out_err:
 399         inode->i_nlink = 0;
 400         hfsplus_delete_inode(inode);
 401         iput(inode);
 402 out:
 403         mutex_unlock(&sbi->vh_mutex);
 404         return res;
 405 }
 406
 407 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 408                          int mode, dev_t rdev)
 409 {
 410         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 411         struct inode *inode;
 412         int res = -ENOSPC;
 413
 414         mutex_lock(&sbi->vh_mutex);
 415         inode = hfsplus_new_inode(dir->i_sb, mode);
 416         if (!inode)
 417                 goto out;
 418
 419         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 420         if (res) {
 421                 inode->i_nlink = 0;
 422                 hfsplus_delete_inode(inode);
 423                 iput(inode);
 424                 goto out;
 425         }
 426
 427         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 428                 init_special_inode(inode, mode, rdev);
 429
 430         hfsplus_instantiate(dentry, inode, inode->i_ino);
 431         mark_inode_dirty(inode);
 432 out:
 433         mutex_unlock(&sbi->vh_mutex);
 434         return res;
 435 }
 436
 437 static int hfsplus_create(struct inode *dir, struct dentry *dentry, int mode,
 438                           struct nameidata *nd)
 439 {
 440         return hfsplus_mknod(dir, dentry, mode, 0);
 441 }
 442
 443 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 444 {
 445         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 446 }
 447
 448 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 449                           struct inode *new_dir, struct dentry *new_dentry)
 450 {
 451         int res;
 452
 453         /* Unlink destination if it already exists */
 454         if (new_dentry->d_inode) {
 455                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 456                         res = hfsplus_rmdir(new_dir, new_dentry);
 457                 else
 458                         res = hfsplus_unlink(new_dir, new_dentry);
 459                 if (res)
 460                         return res;
 461         }
 462
 463         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 464                                  old_dir, &old_dentry->d_name,
 465                                  new_dir, &new_dentry->d_name);
 466         if (!res)
 467                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 468         return res;
 469 }
 470
 471 const struct inode_operations hfsplus_dir_inode_operations = {
 472         .lookup         = hfsplus_lookup,
 473         .create         = hfsplus_create,
 474         .link           = hfsplus_link,
 475         .unlink         = hfsplus_unlink,
 476         .mkdir          = hfsplus_mkdir,
 477         .rmdir          = hfsplus_rmdir,
 478         .symlink        = hfsplus_symlink,
 479         .mknod          = hfsplus_mknod,
 480         .rename         = hfsplus_rename,
 481 };
 482
 483 const struct file_operations hfsplus_dir_operations = {
 484         .read           = generic_read_dir,
 485         .readdir        = hfsplus_readdir,
 486         .unlocked_ioctl = hfsplus_ioctl,
 487         .llseek         = generic_file_llseek,
 488         .release        = hfsplus_dir_release,
 489 };