fs/hfsplus/dir.c

   1 /*
   2  *  linux/fs/hfsplus/dir.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer ([email protected])
   6  * (C) 2003 Ardis Technologies <[email protected]>
   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 #include <linux/nls.h>
  16
  17 #include "hfsplus_fs.h"
  18 #include "hfsplus_raw.h"
  19 #include "xattr.h"
  20 #include "acl.h"
  21
  22 static inline void hfsplus_instantiate(struct dentry *dentry,
  23                                        struct inode *inode, u32 cnid)
  24 {
  25         dentry->d_fsdata = (void *)(unsigned long)cnid;
  26         d_instantiate(dentry, inode);
  27 }
  28
  29 /* Find the entry inside dir named dentry->d_name */
  30 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
  31                                      unsigned int flags)
  32 {
  33         struct inode *inode = NULL;
  34         struct hfs_find_data fd;
  35         struct super_block *sb;
  36         hfsplus_cat_entry entry;
  37         int err;
  38         u32 cnid, linkid = 0;
  39         u16 type;
  40
  41         sb = dir->i_sb;
  42
  43         dentry->d_fsdata = NULL;
  44         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
  45         if (err)
  46                 return ERR_PTR(err);
  47         err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino,
  48                         &dentry->d_name);
  49         if (unlikely(err < 0))
  50                 goto fail;
  51 again:
  52         err = hfs_brec_read(&fd, &entry, sizeof(entry));
  53         if (err) {
  54                 if (err == -ENOENT) {
  55                         hfs_find_exit(&fd);
  56                         /* No such entry */
  57                         inode = NULL;
  58                         goto out;
  59                 }
  60                 goto fail;
  61         }
  62         type = be16_to_cpu(entry.type);
  63         if (type == HFSPLUS_FOLDER) {
  64                 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
  65                         err = -EIO;
  66                         goto fail;
  67                 }
  68                 cnid = be32_to_cpu(entry.folder.id);
  69                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  70         } else if (type == HFSPLUS_FILE) {
  71                 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
  72                         err = -EIO;
  73                         goto fail;
  74                 }
  75                 cnid = be32_to_cpu(entry.file.id);
  76                 if (entry.file.user_info.fdType ==
  77                                 cpu_to_be32(HFSP_HARDLINK_TYPE) &&
  78                                 entry.file.user_info.fdCreator ==
  79                                 cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
  80                                 (entry.file.create_date ==
  81                                         HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
  82                                                 create_date ||
  83                                 entry.file.create_date ==
  84                                         HFSPLUS_I(d_inode(sb->s_root))->
  85                                                 create_date) &&
  86                                 HFSPLUS_SB(sb)->hidden_dir) {
  87                         struct qstr str;
  88                         char name[32];
  89
  90                         if (dentry->d_fsdata) {
  91                                 /*
  92                                  * We found a link pointing to another link,
  93                                  * so ignore it and treat it as regular file.
  94                                  */
  95                                 cnid = (unsigned long)dentry->d_fsdata;
  96                                 linkid = 0;
  97                         } else {
  98                                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  99                                 linkid =
 100                                         be32_to_cpu(entry.file.permissions.dev);
 101                                 str.len = sprintf(name, "iNode%d", linkid);
 102                                 str.name = name;
 103                                 err = hfsplus_cat_build_key(sb, fd.search_key,
 104                                         HFSPLUS_SB(sb)->hidden_dir->i_ino,
 105                                         &str);
 106                                 if (unlikely(err < 0))
 107                                         goto fail;
 108                                 goto again;
 109                         }
 110                 } else if (!dentry->d_fsdata)
 111                         dentry->d_fsdata = (void *)(unsigned long)cnid;
 112         } else {
 113                 pr_err("invalid catalog entry type in lookup\n");
 114                 err = -EIO;
 115                 goto fail;
 116         }
 117         hfs_find_exit(&fd);
 118         inode = hfsplus_iget(dir->i_sb, cnid);
 119         if (IS_ERR(inode))
 120                 return ERR_CAST(inode);
 121         if (S_ISREG(inode->i_mode))
 122                 HFSPLUS_I(inode)->linkid = linkid;
 123 out:
 124         d_add(dentry, inode);
 125         return NULL;
 126 fail:
 127         hfs_find_exit(&fd);
 128         return ERR_PTR(err);
 129 }
 130
 131 static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
 132 {
 133         struct inode *inode = file_inode(file);
 134         struct super_block *sb = inode->i_sb;
 135         int len, err;
 136         char *strbuf;
 137         hfsplus_cat_entry entry;
 138         struct hfs_find_data fd;
 139         struct hfsplus_readdir_data *rd;
 140         u16 type;
 141
 142         if (file->f_pos >= inode->i_size)
 143                 return 0;
 144
 145         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
 146         if (err)
 147                 return err;
 148         strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN + 1, GFP_KERNEL);
 149         if (!strbuf) {
 150                 err = -ENOMEM;
 151                 goto out;
 152         }
 153         hfsplus_cat_build_key_with_cnid(sb, fd.search_key, inode->i_ino);
 154         err = hfs_brec_find(&fd, hfs_find_rec_by_key);
 155         if (err)
 156                 goto out;
 157
 158         if (ctx->pos == 0) {
 159                 /* This is completely artificial... */
 160                 if (!dir_emit_dot(file, ctx))
 161                         goto out;
 162                 ctx->pos = 1;
 163         }
 164         if (ctx->pos == 1) {
 165                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 166                         err = -EIO;
 167                         goto out;
 168                 }
 169
 170                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 171                         fd.entrylength);
 172                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 173                         pr_err("bad catalog folder thread\n");
 174                         err = -EIO;
 175                         goto out;
 176                 }
 177                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 178                         pr_err("truncated catalog thread\n");
 179                         err = -EIO;
 180                         goto out;
 181                 }
 182                 if (!dir_emit(ctx, "..", 2,
 183                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 184                         goto out;
 185                 ctx->pos = 2;
 186         }
 187         if (ctx->pos >= inode->i_size)
 188                 goto out;
 189         err = hfs_brec_goto(&fd, ctx->pos - 1);
 190         if (err)
 191                 goto out;
 192         for (;;) {
 193                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 194                         pr_err("walked past end of dir\n");
 195                         err = -EIO;
 196                         goto out;
 197                 }
 198
 199                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 200                         err = -EIO;
 201                         goto out;
 202                 }
 203
 204                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 205                         fd.entrylength);
 206                 type = be16_to_cpu(entry.type);
 207                 len = NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN;
 208                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 209                 if (err)
 210                         goto out;
 211                 if (type == HFSPLUS_FOLDER) {
 212                         if (fd.entrylength <
 213                                         sizeof(struct hfsplus_cat_folder)) {
 214                                 pr_err("small dir entry\n");
 215                                 err = -EIO;
 216                                 goto out;
 217                         }
 218                         if (HFSPLUS_SB(sb)->hidden_dir &&
 219                             HFSPLUS_SB(sb)->hidden_dir->i_ino ==
 220                                         be32_to_cpu(entry.folder.id))
 221                                 goto next;
 222                         if (!dir_emit(ctx, strbuf, len,
 223                                     be32_to_cpu(entry.folder.id), DT_DIR))
 224                                 break;
 225                 } else if (type == HFSPLUS_FILE) {
 226                         u16 mode;
 227                         unsigned type = DT_UNKNOWN;
 228
 229                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 230                                 pr_err("small file entry\n");
 231                                 err = -EIO;
 232                                 goto out;
 233                         }
 234
 235                         mode = be16_to_cpu(entry.file.permissions.mode);
 236                         if (S_ISREG(mode))
 237                                 type = DT_REG;
 238                         else if (S_ISLNK(mode))
 239                                 type = DT_LNK;
 240                         else if (S_ISFIFO(mode))
 241                                 type = DT_FIFO;
 242                         else if (S_ISCHR(mode))
 243                                 type = DT_CHR;
 244                         else if (S_ISBLK(mode))
 245                                 type = DT_BLK;
 246                         else if (S_ISSOCK(mode))
 247                                 type = DT_SOCK;
 248
 249                         if (!dir_emit(ctx, strbuf, len,
 250                                       be32_to_cpu(entry.file.id), type))
 251                                 break;
 252                 } else {
 253                         pr_err("bad catalog entry type\n");
 254                         err = -EIO;
 255                         goto out;
 256                 }
 257 next:
 258                 ctx->pos++;
 259                 if (ctx->pos >= inode->i_size)
 260                         goto out;
 261                 err = hfs_brec_goto(&fd, 1);
 262                 if (err)
 263                         goto out;
 264         }
 265         rd = file->private_data;
 266         if (!rd) {
 267                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 268                 if (!rd) {
 269                         err = -ENOMEM;
 270                         goto out;
 271                 }
 272                 file->private_data = rd;
 273                 rd->file = file;
 274                 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
 275         }
 276         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 277 out:
 278         kfree(strbuf);
 279         hfs_find_exit(&fd);
 280         return err;
 281 }
 282
 283 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 284 {
 285         struct hfsplus_readdir_data *rd = file->private_data;
 286         if (rd) {
 287                 inode_lock(inode);
 288                 list_del(&rd->list);
 289                 inode_unlock(inode);
 290                 kfree(rd);
 291         }
 292         return 0;
 293 }
 294
 295 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 296                         struct dentry *dst_dentry)
 297 {
 298         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 299         struct inode *inode = d_inode(src_dentry);
 300         struct inode *src_dir = d_inode(src_dentry->d_parent);
 301         struct qstr str;
 302         char name[32];
 303         u32 cnid, id;
 304         int res;
 305
 306         if (HFSPLUS_IS_RSRC(inode))
 307                 return -EPERM;
 308         if (!S_ISREG(inode->i_mode))
 309                 return -EPERM;
 310
 311         mutex_lock(&sbi->vh_mutex);
 312         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 313                 for (;;) {
 314                         get_random_bytes(&id, sizeof(cnid));
 315                         id &= 0x3fffffff;
 316                         str.name = name;
 317                         str.len = sprintf(name, "iNode%d", id);
 318                         res = hfsplus_rename_cat(inode->i_ino,
 319                                                  src_dir, &src_dentry->d_name,
 320                                                  sbi->hidden_dir, &str);
 321                         if (!res)
 322                                 break;
 323                         if (res != -EEXIST)
 324                                 goto out;
 325                 }
 326                 HFSPLUS_I(inode)->linkid = id;
 327                 cnid = sbi->next_cnid++;
 328                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 329                 res = hfsplus_create_cat(cnid, src_dir,
 330                         &src_dentry->d_name, inode);
 331                 if (res)
 332                         /* panic? */
 333                         goto out;
 334                 sbi->file_count++;
 335         }
 336         cnid = sbi->next_cnid++;
 337         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 338         if (res)
 339                 goto out;
 340
 341         inc_nlink(inode);
 342         hfsplus_instantiate(dst_dentry, inode, cnid);
 343         ihold(inode);
 344         inode->i_ctime = CURRENT_TIME_SEC;
 345         mark_inode_dirty(inode);
 346         sbi->file_count++;
 347         hfsplus_mark_mdb_dirty(dst_dir->i_sb);
 348 out:
 349         mutex_unlock(&sbi->vh_mutex);
 350         return res;
 351 }
 352
 353 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 354 {
 355         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 356         struct inode *inode = d_inode(dentry);
 357         struct qstr str;
 358         char name[32];
 359         u32 cnid;
 360         int res;
 361
 362         if (HFSPLUS_IS_RSRC(inode))
 363                 return -EPERM;
 364
 365         mutex_lock(&sbi->vh_mutex);
 366         cnid = (u32)(unsigned long)dentry->d_fsdata;
 367         if (inode->i_ino == cnid &&
 368             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 369                 str.name = name;
 370                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 371                 res = hfsplus_rename_cat(inode->i_ino,
 372                                          dir, &dentry->d_name,
 373                                          sbi->hidden_dir, &str);
 374                 if (!res) {
 375                         inode->i_flags |= S_DEAD;
 376                         drop_nlink(inode);
 377                 }
 378                 goto out;
 379         }
 380         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 381         if (res)
 382                 goto out;
 383
 384         if (inode->i_nlink > 0)
 385                 drop_nlink(inode);
 386         if (inode->i_ino == cnid)
 387                 clear_nlink(inode);
 388         if (!inode->i_nlink) {
 389                 if (inode->i_ino != cnid) {
 390                         sbi->file_count--;
 391                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 392                                 res = hfsplus_delete_cat(inode->i_ino,
 393                                                          sbi->hidden_dir,
 394                                                          NULL);
 395                                 if (!res)
 396                                         hfsplus_delete_inode(inode);
 397                         } else
 398                                 inode->i_flags |= S_DEAD;
 399                 } else
 400                         hfsplus_delete_inode(inode);
 401         } else
 402                 sbi->file_count--;
 403         inode->i_ctime = CURRENT_TIME_SEC;
 404         mark_inode_dirty(inode);
 405 out:
 406         mutex_unlock(&sbi->vh_mutex);
 407         return res;
 408 }
 409
 410 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 411 {
 412         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 413         struct inode *inode = d_inode(dentry);
 414         int res;
 415
 416         if (inode->i_size != 2)
 417                 return -ENOTEMPTY;
 418
 419         mutex_lock(&sbi->vh_mutex);
 420         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 421         if (res)
 422                 goto out;
 423         clear_nlink(inode);
 424         inode->i_ctime = CURRENT_TIME_SEC;
 425         hfsplus_delete_inode(inode);
 426         mark_inode_dirty(inode);
 427 out:
 428         mutex_unlock(&sbi->vh_mutex);
 429         return res;
 430 }
 431
 432 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 433                            const char *symname)
 434 {
 435         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 436         struct inode *inode;
 437         int res = -ENOMEM;
 438
 439         mutex_lock(&sbi->vh_mutex);
 440         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 441         if (!inode)
 442                 goto out;
 443
 444         res = page_symlink(inode, symname, strlen(symname) + 1);
 445         if (res)
 446                 goto out_err;
 447
 448         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 449         if (res)
 450                 goto out_err;
 451
 452         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 453         if (res == -EOPNOTSUPP)
 454                 res = 0; /* Operation is not supported. */
 455         else if (res) {
 456                 /* Try to delete anyway without error analysis. */
 457                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 458                 goto out_err;
 459         }
 460
 461         hfsplus_instantiate(dentry, inode, inode->i_ino);
 462         mark_inode_dirty(inode);
 463         goto out;
 464
 465 out_err:
 466         clear_nlink(inode);
 467         hfsplus_delete_inode(inode);
 468         iput(inode);
 469 out:
 470         mutex_unlock(&sbi->vh_mutex);
 471         return res;
 472 }
 473
 474 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 475                          umode_t mode, dev_t rdev)
 476 {
 477         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 478         struct inode *inode;
 479         int res = -ENOMEM;
 480
 481         mutex_lock(&sbi->vh_mutex);
 482         inode = hfsplus_new_inode(dir->i_sb, mode);
 483         if (!inode)
 484                 goto out;
 485
 486         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 487                 init_special_inode(inode, mode, rdev);
 488
 489         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 490         if (res)
 491                 goto failed_mknod;
 492
 493         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 494         if (res == -EOPNOTSUPP)
 495                 res = 0; /* Operation is not supported. */
 496         else if (res) {
 497                 /* Try to delete anyway without error analysis. */
 498                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 499                 goto failed_mknod;
 500         }
 501
 502         hfsplus_instantiate(dentry, inode, inode->i_ino);
 503         mark_inode_dirty(inode);
 504         goto out;
 505
 506 failed_mknod:
 507         clear_nlink(inode);
 508         hfsplus_delete_inode(inode);
 509         iput(inode);
 510 out:
 511         mutex_unlock(&sbi->vh_mutex);
 512         return res;
 513 }
 514
 515 static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 516                           bool excl)
 517 {
 518         return hfsplus_mknod(dir, dentry, mode, 0);
 519 }
 520
 521 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 522 {
 523         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 524 }
 525
 526 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 527                           struct inode *new_dir, struct dentry *new_dentry)
 528 {
 529         int res;
 530
 531         /* Unlink destination if it already exists */
 532         if (d_really_is_positive(new_dentry)) {
 533                 if (d_is_dir(new_dentry))
 534                         res = hfsplus_rmdir(new_dir, new_dentry);
 535                 else
 536                         res = hfsplus_unlink(new_dir, new_dentry);
 537                 if (res)
 538                         return res;
 539         }
 540
 541         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 542                                  old_dir, &old_dentry->d_name,
 543                                  new_dir, &new_dentry->d_name);
 544         if (!res)
 545                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 546         return res;
 547 }
 548
 549 const struct inode_operations hfsplus_dir_inode_operations = {
 550         .lookup                 = hfsplus_lookup,
 551         .create                 = hfsplus_create,
 552         .link                   = hfsplus_link,
 553         .unlink                 = hfsplus_unlink,
 554         .mkdir                  = hfsplus_mkdir,
 555         .rmdir                  = hfsplus_rmdir,
 556         .symlink                = hfsplus_symlink,
 557         .mknod                  = hfsplus_mknod,
 558         .rename                 = hfsplus_rename,
 559         .setxattr               = generic_setxattr,
 560         .getxattr               = generic_getxattr,
 561         .listxattr              = hfsplus_listxattr,
 562         .removexattr            = generic_removexattr,
 563 #ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
 564         .get_acl                = hfsplus_get_posix_acl,
 565         .set_acl                = hfsplus_set_posix_acl,
 566 #endif
 567 };
 568
 569 const struct file_operations hfsplus_dir_operations = {
 570         .fsync          = hfsplus_file_fsync,
 571         .read           = generic_read_dir,
 572         .iterate        = hfsplus_readdir,
 573         .unlocked_ioctl = hfsplus_ioctl,
 574         .llseek         = generic_file_llseek,
 575         .release        = hfsplus_dir_release,
 576 };