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