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                 list_del(&rd->list);
 235                 kfree(rd);
 236         }
 237         return 0;
 238 }
 239
 240 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 241                         struct dentry *dst_dentry)
 242 {
 243         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 244         struct inode *inode = src_dentry->d_inode;
 245         struct inode *src_dir = src_dentry->d_parent->d_inode;
 246         struct qstr str;
 247         char name[32];
 248         u32 cnid, id;
 249         int res;
 250
 251         if (HFSPLUS_IS_RSRC(inode))
 252                 return -EPERM;
 253
 254         mutex_lock(&sbi->vh_mutex);
 255         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 256                 for (;;) {
 257                         get_random_bytes(&id, sizeof(cnid));
 258                         id &= 0x3fffffff;
 259                         str.name = name;
 260                         str.len = sprintf(name, "iNode%d", id);
 261                         res = hfsplus_rename_cat(inode->i_ino,
 262                                                  src_dir, &src_dentry->d_name,
 263                                                  sbi->hidden_dir, &str);
 264                         if (!res)
 265                                 break;
 266                         if (res != -EEXIST)
 267                                 goto out;
 268                 }
 269                 HFSPLUS_I(inode)->dev = id;
 270                 cnid = sbi->next_cnid++;
 271                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 272                 res = hfsplus_create_cat(cnid, src_dir, &src_dentry->d_name, inode);
 273                 if (res)
 274                         /* panic? */
 275                         goto out;
 276                 sbi->file_count++;
 277         }
 278         cnid = sbi->next_cnid++;
 279         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 280         if (res)
 281                 goto out;
 282
 283         inc_nlink(inode);
 284         hfsplus_instantiate(dst_dentry, inode, cnid);
 285         atomic_inc(&inode->i_count);
 286         inode->i_ctime = CURRENT_TIME_SEC;
 287         mark_inode_dirty(inode);
 288         sbi->file_count++;
 289         dst_dir->i_sb->s_dirt = 1;
 290 out:
 291         mutex_unlock(&sbi->vh_mutex);
 292         return res;
 293 }
 294
 295 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 296 {
 297         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 298         struct inode *inode = dentry->d_inode;
 299         struct qstr str;
 300         char name[32];
 301         u32 cnid;
 302         int res;
 303
 304         if (HFSPLUS_IS_RSRC(inode))
 305                 return -EPERM;
 306
 307         mutex_lock(&sbi->vh_mutex);
 308         cnid = (u32)(unsigned long)dentry->d_fsdata;
 309         if (inode->i_ino == cnid &&
 310             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 311                 str.name = name;
 312                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 313                 res = hfsplus_rename_cat(inode->i_ino,
 314                                          dir, &dentry->d_name,
 315                                          sbi->hidden_dir, &str);
 316                 if (!res)
 317                         inode->i_flags |= S_DEAD;
 318                 goto out;
 319         }
 320         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 321         if (res)
 322                 goto out;
 323
 324         if (inode->i_nlink > 0)
 325                 drop_nlink(inode);
 326         if (inode->i_ino == cnid)
 327                 clear_nlink(inode);
 328         if (!inode->i_nlink) {
 329                 if (inode->i_ino != cnid) {
 330                         sbi->file_count--;
 331                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 332                                 res = hfsplus_delete_cat(inode->i_ino,
 333                                                          sbi->hidden_dir,
 334                                                          NULL);
 335                                 if (!res)
 336                                         hfsplus_delete_inode(inode);
 337                         } else
 338                                 inode->i_flags |= S_DEAD;
 339                 } else
 340                         hfsplus_delete_inode(inode);
 341         } else
 342                 sbi->file_count--;
 343         inode->i_ctime = CURRENT_TIME_SEC;
 344         mark_inode_dirty(inode);
 345 out:
 346         mutex_unlock(&sbi->vh_mutex);
 347         return res;
 348 }
 349
 350 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 351 {
 352         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 353         struct inode *inode = dentry->d_inode;
 354         int res;
 355
 356         if (inode->i_size != 2)
 357                 return -ENOTEMPTY;
 358
 359         mutex_lock(&sbi->vh_mutex);
 360         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 361         if (res)
 362                 goto out;
 363         clear_nlink(inode);
 364         inode->i_ctime = CURRENT_TIME_SEC;
 365         hfsplus_delete_inode(inode);
 366         mark_inode_dirty(inode);
 367 out:
 368         mutex_unlock(&sbi->vh_mutex);
 369         return res;
 370 }
 371
 372 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 373                            const char *symname)
 374 {
 375         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 376         struct inode *inode;
 377         int res = -ENOSPC;
 378
 379         mutex_lock(&sbi->vh_mutex);
 380         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 381         if (!inode)
 382                 goto out;
 383
 384         res = page_symlink(inode, symname, strlen(symname) + 1);
 385         if (res)
 386                 goto out_err;
 387
 388         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 389         if (res)
 390                 goto out_err;
 391
 392         hfsplus_instantiate(dentry, inode, inode->i_ino);
 393         mark_inode_dirty(inode);
 394         goto out;
 395
 396 out_err:
 397         inode->i_nlink = 0;
 398         hfsplus_delete_inode(inode);
 399         iput(inode);
 400 out:
 401         mutex_unlock(&sbi->vh_mutex);
 402         return res;
 403 }
 404
 405 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 406                          int mode, dev_t rdev)
 407 {
 408         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 409         struct inode *inode;
 410         int res = -ENOSPC;
 411
 412         mutex_lock(&sbi->vh_mutex);
 413         inode = hfsplus_new_inode(dir->i_sb, mode);
 414         if (!inode)
 415                 goto out;
 416
 417         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 418         if (res) {
 419                 inode->i_nlink = 0;
 420                 hfsplus_delete_inode(inode);
 421                 iput(inode);
 422                 goto out;
 423         }
 424
 425         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 426                 init_special_inode(inode, mode, rdev);
 427
 428         hfsplus_instantiate(dentry, inode, inode->i_ino);
 429         mark_inode_dirty(inode);
 430 out:
 431         mutex_unlock(&sbi->vh_mutex);
 432         return res;
 433 }
 434
 435 static int hfsplus_create(struct inode *dir, struct dentry *dentry, int mode,
 436                           struct nameidata *nd)
 437 {
 438         return hfsplus_mknod(dir, dentry, mode, 0);
 439 }
 440
 441 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 442 {
 443         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 444 }
 445
 446 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 447                           struct inode *new_dir, struct dentry *new_dentry)
 448 {
 449         int res;
 450
 451         /* Unlink destination if it already exists */
 452         if (new_dentry->d_inode) {
 453                 res = hfsplus_unlink(new_dir, new_dentry);
 454                 if (res)
 455                         return res;
 456         }
 457
 458         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 459                                  old_dir, &old_dentry->d_name,
 460                                  new_dir, &new_dentry->d_name);
 461         if (!res)
 462                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 463         return res;
 464 }
 465
 466 const struct inode_operations hfsplus_dir_inode_operations = {
 467         .lookup         = hfsplus_lookup,
 468         .create         = hfsplus_create,
 469         .link           = hfsplus_link,
 470         .unlink         = hfsplus_unlink,
 471         .mkdir          = hfsplus_mkdir,
 472         .rmdir          = hfsplus_rmdir,
 473         .symlink        = hfsplus_symlink,
 474         .mknod          = hfsplus_mknod,
 475         .rename         = hfsplus_rename,
 476 };
 477
 478 const struct file_operations hfsplus_dir_operations = {
 479         .read           = generic_read_dir,
 480         .readdir        = hfsplus_readdir,
 481         .unlocked_ioctl = hfsplus_ioctl,
 482         .llseek         = generic_file_llseek,
 483         .release        = hfsplus_dir_release,
 484 };