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