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/sched.h>
  14 #include <linux/slab.h>
  15 #include <linux/random.h>
  16
  17 #include "hfsplus_fs.h"
  18 #include "hfsplus_raw.h"
  19
  20 static inline void hfsplus_instantiate(struct dentry *dentry,
  21                                        struct inode *inode, u32 cnid)
  22 {
  23         dentry->d_fsdata = (void *)(unsigned long)cnid;
  24         d_instantiate(dentry, inode);
  25 }
  26
  27 /* Find the entry inside dir named dentry->d_name */
  28 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
  29                                      struct nameidata *nd)
  30 {
  31         struct inode *inode = NULL;
  32         struct hfs_find_data fd;
  33         struct super_block *sb;
  34         hfsplus_cat_entry entry;
  35         int err;
  36         u32 cnid, linkid = 0;
  37         u16 type;
  38
  39         sb = dir->i_sb;
  40         dentry->d_fsdata = NULL;
  41         hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
  42         hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
  43 again:
  44         err = hfs_brec_read(&fd, &entry, sizeof(entry));
  45         if (err) {
  46                 if (err == -ENOENT) {
  47                         hfs_find_exit(&fd);
  48                         /* No such entry */
  49                         inode = NULL;
  50                         goto out;
  51                 }
  52                 goto fail;
  53         }
  54         type = be16_to_cpu(entry.type);
  55         if (type == HFSPLUS_FOLDER) {
  56                 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
  57                         err = -EIO;
  58                         goto fail;
  59                 }
  60                 cnid = be32_to_cpu(entry.folder.id);
  61                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  62         } else if (type == HFSPLUS_FILE) {
  63                 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
  64                         err = -EIO;
  65                         goto fail;
  66                 }
  67                 cnid = be32_to_cpu(entry.file.id);
  68                 if (entry.file.user_info.fdType == cpu_to_be32(HFSP_HARDLINK_TYPE) &&
  69                     entry.file.user_info.fdCreator == cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
  70                     (entry.file.create_date == HFSPLUS_I(HFSPLUS_SB(sb).hidden_dir).create_date ||
  71                      entry.file.create_date == HFSPLUS_I(sb->s_root->d_inode).create_date) &&
  72                     HFSPLUS_SB(sb).hidden_dir) {
  73                         struct qstr str;
  74                         char name[32];
  75
  76                         if (dentry->d_fsdata) {
  77                                 /*
  78                                  * We found a link pointing to another link,
  79                                  * so ignore it and treat it as regular file.
  80                                  */
  81                                 cnid = (unsigned long)dentry->d_fsdata;
  82                                 linkid = 0;
  83                         } else {
  84                                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  85                                 linkid = be32_to_cpu(entry.file.permissions.dev);
  86                                 str.len = sprintf(name, "iNode%d", linkid);
  87                                 str.name = name;
  88                                 hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_SB(sb).hidden_dir->i_ino, &str);
  89                                 goto again;
  90                         }
  91                 } else if (!dentry->d_fsdata)
  92                         dentry->d_fsdata = (void *)(unsigned long)cnid;
  93         } else {
  94                 printk(KERN_ERR "hfs: invalid catalog entry type in lookup\n");
  95                 err = -EIO;
  96                 goto fail;
  97         }
  98         hfs_find_exit(&fd);
  99         inode = iget(dir->i_sb, cnid);
 100         if (!inode)
 101                 return ERR_PTR(-EACCES);
 102         if (S_ISREG(inode->i_mode))
 103                 HFSPLUS_I(inode).dev = linkid;
 104 out:
 105         d_add(dentry, inode);
 106         return NULL;
 107 fail:
 108         hfs_find_exit(&fd);
 109         return ERR_PTR(err);
 110 }
 111
 112 static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
 113 {
 114         struct inode *inode = filp->f_dentry->d_inode;
 115         struct super_block *sb = inode->i_sb;
 116         int len, err;
 117         char strbuf[HFSPLUS_MAX_STRLEN + 1];
 118         hfsplus_cat_entry entry;
 119         struct hfs_find_data fd;
 120         struct hfsplus_readdir_data *rd;
 121         u16 type;
 122
 123         if (filp->f_pos >= inode->i_size)
 124                 return 0;
 125
 126         hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
 127         hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
 128         err = hfs_brec_find(&fd);
 129         if (err)
 130                 goto out;
 131
 132         switch ((u32)filp->f_pos) {
 133         case 0:
 134                 /* This is completely artificial... */
 135                 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
 136                         goto out;
 137                 filp->f_pos++;
 138                 /* fall through */
 139         case 1:
 140                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
 141                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 142                         printk(KERN_ERR "hfs: bad catalog folder thread\n");
 143                         err = -EIO;
 144                         goto out;
 145                 }
 146                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 147                         printk(KERN_ERR "hfs: truncated catalog thread\n");
 148                         err = -EIO;
 149                         goto out;
 150                 }
 151                 if (filldir(dirent, "..", 2, 1,
 152                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 153                         goto out;
 154                 filp->f_pos++;
 155                 /* fall through */
 156         default:
 157                 if (filp->f_pos >= inode->i_size)
 158                         goto out;
 159                 err = hfs_brec_goto(&fd, filp->f_pos - 1);
 160                 if (err)
 161                         goto out;
 162         }
 163
 164         for (;;) {
 165                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 166                         printk(KERN_ERR "hfs: walked past end of dir\n");
 167                         err = -EIO;
 168                         goto out;
 169                 }
 170                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
 171                 type = be16_to_cpu(entry.type);
 172                 len = HFSPLUS_MAX_STRLEN;
 173                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 174                 if (err)
 175                         goto out;
 176                 if (type == HFSPLUS_FOLDER) {
 177                         if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
 178                                 printk(KERN_ERR "hfs: small dir entry\n");
 179                                 err = -EIO;
 180                                 goto out;
 181                         }
 182                         if (HFSPLUS_SB(sb).hidden_dir &&
 183                             HFSPLUS_SB(sb).hidden_dir->i_ino == be32_to_cpu(entry.folder.id))
 184                                 goto next;
 185                         if (filldir(dirent, strbuf, len, filp->f_pos,
 186                                     be32_to_cpu(entry.folder.id), DT_DIR))
 187                                 break;
 188                 } else if (type == HFSPLUS_FILE) {
 189                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 190                                 printk(KERN_ERR "hfs: small file entry\n");
 191                                 err = -EIO;
 192                                 goto out;
 193                         }
 194                         if (filldir(dirent, strbuf, len, filp->f_pos,
 195                                     be32_to_cpu(entry.file.id), DT_REG))
 196                                 break;
 197                 } else {
 198                         printk(KERN_ERR "hfs: bad catalog entry type\n");
 199                         err = -EIO;
 200                         goto out;
 201                 }
 202         next:
 203                 filp->f_pos++;
 204                 if (filp->f_pos >= inode->i_size)
 205                         goto out;
 206                 err = hfs_brec_goto(&fd, 1);
 207                 if (err)
 208                         goto out;
 209         }
 210         rd = filp->private_data;
 211         if (!rd) {
 212                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 213                 if (!rd) {
 214                         err = -ENOMEM;
 215                         goto out;
 216                 }
 217                 filp->private_data = rd;
 218                 rd->file = filp;
 219                 list_add(&rd->list, &HFSPLUS_I(inode).open_dir_list);
 220         }
 221         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 222 out:
 223         hfs_find_exit(&fd);
 224         return err;
 225 }
 226
 227 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 228 {
 229         struct hfsplus_readdir_data *rd = file->private_data;
 230         if (rd) {
 231                 list_del(&rd->list);
 232                 kfree(rd);
 233         }
 234         return 0;
 235 }
 236
 237 static int hfsplus_create(struct inode *dir, struct dentry *dentry, int mode,
 238                           struct nameidata *nd)
 239 {
 240         struct inode *inode;
 241         int res;
 242
 243         inode = hfsplus_new_inode(dir->i_sb, mode);
 244         if (!inode)
 245                 return -ENOSPC;
 246
 247         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 248         if (res) {
 249                 inode->i_nlink = 0;
 250                 hfsplus_delete_inode(inode);
 251                 iput(inode);
 252                 return res;
 253         }
 254         hfsplus_instantiate(dentry, inode, inode->i_ino);
 255         mark_inode_dirty(inode);
 256         return 0;
 257 }
 258
 259 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 260                         struct dentry *dst_dentry)
 261 {
 262         struct super_block *sb = dst_dir->i_sb;
 263         struct inode *inode = src_dentry->d_inode;
 264         struct inode *src_dir = src_dentry->d_parent->d_inode;
 265         struct qstr str;
 266         char name[32];
 267         u32 cnid, id;
 268         int res;
 269
 270         if (HFSPLUS_IS_RSRC(inode))
 271                 return -EPERM;
 272
 273         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 274                 for (;;) {
 275                         get_random_bytes(&id, sizeof(cnid));
 276                         id &= 0x3fffffff;
 277                         str.name = name;
 278                         str.len = sprintf(name, "iNode%d", id);
 279                         res = hfsplus_rename_cat(inode->i_ino,
 280                                                  src_dir, &src_dentry->d_name,
 281                                                  HFSPLUS_SB(sb).hidden_dir, &str);
 282                         if (!res)
 283                                 break;
 284                         if (res != -EEXIST)
 285                                 return res;
 286                 }
 287                 HFSPLUS_I(inode).dev = id;
 288                 cnid = HFSPLUS_SB(sb).next_cnid++;
 289                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 290                 res = hfsplus_create_cat(cnid, src_dir, &src_dentry->d_name, inode);
 291                 if (res)
 292                         /* panic? */
 293                         return res;
 294                 HFSPLUS_SB(sb).file_count++;
 295         }
 296         cnid = HFSPLUS_SB(sb).next_cnid++;
 297         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 298         if (res)
 299                 return res;
 300
 301         inc_nlink(inode);
 302         hfsplus_instantiate(dst_dentry, inode, cnid);
 303         atomic_inc(&inode->i_count);
 304         inode->i_ctime = CURRENT_TIME_SEC;
 305         mark_inode_dirty(inode);
 306         HFSPLUS_SB(sb).file_count++;
 307         sb->s_dirt = 1;
 308
 309         return 0;
 310 }
 311
 312 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 313 {
 314         struct super_block *sb = dir->i_sb;
 315         struct inode *inode = dentry->d_inode;
 316         struct qstr str;
 317         char name[32];
 318         u32 cnid;
 319         int res;
 320
 321         if (HFSPLUS_IS_RSRC(inode))
 322                 return -EPERM;
 323
 324         cnid = (u32)(unsigned long)dentry->d_fsdata;
 325         if (inode->i_ino == cnid &&
 326             atomic_read(&HFSPLUS_I(inode).opencnt)) {
 327                 str.name = name;
 328                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 329                 res = hfsplus_rename_cat(inode->i_ino,
 330                                          dir, &dentry->d_name,
 331                                          HFSPLUS_SB(sb).hidden_dir, &str);
 332                 if (!res)
 333                         inode->i_flags |= S_DEAD;
 334                 return res;
 335         }
 336         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 337         if (res)
 338                 return res;
 339
 340         if (inode->i_nlink > 0)
 341                 drop_nlink(inode);
 342         hfsplus_delete_inode(inode);
 343         if (inode->i_ino != cnid && !inode->i_nlink) {
 344                 if (!atomic_read(&HFSPLUS_I(inode).opencnt)) {
 345                         res = hfsplus_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
 346                         if (!res)
 347                                 hfsplus_delete_inode(inode);
 348                 } else
 349                         inode->i_flags |= S_DEAD;
 350         } else
 351                 inode->i_nlink = 0;
 352         inode->i_ctime = CURRENT_TIME_SEC;
 353         mark_inode_dirty(inode);
 354
 355         return res;
 356 }
 357
 358 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 359 {
 360         struct inode *inode;
 361         int res;
 362
 363         inode = hfsplus_new_inode(dir->i_sb, S_IFDIR | mode);
 364         if (!inode)
 365                 return -ENOSPC;
 366
 367         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 368         if (res) {
 369                 inode->i_nlink = 0;
 370                 hfsplus_delete_inode(inode);
 371                 iput(inode);
 372                 return res;
 373         }
 374         hfsplus_instantiate(dentry, inode, inode->i_ino);
 375         mark_inode_dirty(inode);
 376         return 0;
 377 }
 378
 379 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 380 {
 381         struct inode *inode;
 382         int res;
 383
 384         inode = dentry->d_inode;
 385         if (inode->i_size != 2)
 386                 return -ENOTEMPTY;
 387         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 388         if (res)
 389                 return res;
 390         inode->i_nlink = 0;
 391         inode->i_ctime = CURRENT_TIME_SEC;
 392         hfsplus_delete_inode(inode);
 393         mark_inode_dirty(inode);
 394         return 0;
 395 }
 396
 397 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 398                            const char *symname)
 399 {
 400         struct super_block *sb;
 401         struct inode *inode;
 402         int res;
 403
 404         sb = dir->i_sb;
 405         inode = hfsplus_new_inode(sb, S_IFLNK | S_IRWXUGO);
 406         if (!inode)
 407                 return -ENOSPC;
 408
 409         res = page_symlink(inode, symname, strlen(symname) + 1);
 410         if (res) {
 411                 inode->i_nlink = 0;
 412                 hfsplus_delete_inode(inode);
 413                 iput(inode);
 414                 return res;
 415         }
 416
 417         mark_inode_dirty(inode);
 418         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 419
 420         if (!res) {
 421                 hfsplus_instantiate(dentry, inode, inode->i_ino);
 422                 mark_inode_dirty(inode);
 423         }
 424
 425         return res;
 426 }
 427
 428 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 429                          int mode, dev_t rdev)
 430 {
 431         struct super_block *sb;
 432         struct inode *inode;
 433         int res;
 434
 435         sb = dir->i_sb;
 436         inode = hfsplus_new_inode(sb, mode);
 437         if (!inode)
 438                 return -ENOSPC;
 439
 440         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 441         if (res) {
 442                 inode->i_nlink = 0;
 443                 hfsplus_delete_inode(inode);
 444                 iput(inode);
 445                 return res;
 446         }
 447         init_special_inode(inode, mode, rdev);
 448         hfsplus_instantiate(dentry, inode, inode->i_ino);
 449         mark_inode_dirty(inode);
 450
 451         return 0;
 452 }
 453
 454 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 455                           struct inode *new_dir, struct dentry *new_dentry)
 456 {
 457         int res;
 458
 459         /* Unlink destination if it already exists */
 460         if (new_dentry->d_inode) {
 461                 res = hfsplus_unlink(new_dir, new_dentry);
 462                 if (res)
 463                         return res;
 464         }
 465
 466         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 467                                  old_dir, &old_dentry->d_name,
 468                                  new_dir, &new_dentry->d_name);
 469         if (!res)
 470                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 471         return res;
 472 }
 473
 474 struct inode_operations hfsplus_dir_inode_operations = {
 475         .lookup         = hfsplus_lookup,
 476         .create         = hfsplus_create,
 477         .link           = hfsplus_link,
 478         .unlink         = hfsplus_unlink,
 479         .mkdir          = hfsplus_mkdir,
 480         .rmdir          = hfsplus_rmdir,
 481         .symlink        = hfsplus_symlink,
 482         .mknod          = hfsplus_mknod,
 483         .rename         = hfsplus_rename,
 484 };
 485
 486 const struct file_operations hfsplus_dir_operations = {
 487         .read           = generic_read_dir,
 488         .readdir        = hfsplus_readdir,
 489         .ioctl          = hfsplus_ioctl,
 490         .llseek         = generic_file_llseek,
 491         .release        = hfsplus_dir_release,
 492 };