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