lustre/obdfs/namei.c

   1 /*
   2  *  linux/fs/ext2/namei.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/namei.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  *  Directory entry file type support and forward compatibility hooks
  18  *      for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
  19  *
  20  *  Changes for use in OBDFS
  21  *  Copyright (c) 1999, Seagate Technology Inc.
  22  *
  23  */
  24
  25 #include <asm/uaccess.h>
  26
  27 #include <linux/errno.h>
  28 #include <linux/fs.h>
  29 #include <linux/ext2_fs.h>
  30 #include <linux/fcntl.h>
  31 #include <linux/sched.h>
  32 #include <linux/stat.h>
  33 #include <linux/string.h>
  34 #include <linux/locks.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/iobuf.h>
  37
  38 #include <linux/obd_support.h>
  39 #include "obdfs.h"
  40
  41 /*
  42  * define how far ahead to read directories while searching them.
  43  */
  44 #define NAMEI_RA_CHUNKS  2
  45 #define NAMEI_RA_BLOCKS  4
  46 #define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
  47 #define NAMEI_RA_INDEX(c,b)  (((c) * NAMEI_RA_BLOCKS) + (b))
  48
  49 /*
  50  * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
  51  *
  52  * `len <= EXT2_NAME_LEN' is guaranteed by caller.
  53  * `de != NULL' is guaranteed by caller.
  54  */
  55 static inline int ext2_match (int len, const char * const name,
  56                        struct ext2_dir_entry_2 * de)
  57 {
  58         if (len != de->name_len)
  59                 return 0;
  60         if (!de->inode)
  61                 return 0;
  62         return !memcmp(name, de->name, len);
  63 }
  64
  65 /*
  66  *      ext2_find_entry()
  67  *
  68  * finds an entry in the specified directory with the wanted name. It
  69  * returns the cache buffer in which the entry was found, and the entry
  70  * itself (as a parameter - res_dir). It does NOT read the inode of the
  71  * entry - you'll have to do that yourself if you want to.
  72  */
  73 struct page * obdfs_find_entry (struct inode * dir,
  74                                              const char * const name, int namelen,
  75                                              struct ext2_dir_entry_2 ** res_dir)
  76 {
  77         struct super_block * sb;
  78         unsigned long offset;
  79         struct page * page;
  80
  81         *res_dir = NULL;
  82         sb = dir->i_sb;
  83
  84         if (namelen > EXT2_NAME_LEN)
  85                 return NULL;
  86
  87         for (page = 0, offset = 0; offset < dir->i_size; page++) {
  88                 struct ext2_dir_entry_2 * de;
  89                 char * dlimit;
  90
  91                 page = obdfs_getpage(dir, offset, 0, NOLOCK);
  92                 if ( !page )
  93                         return NULL;
  94
  95                 de = (struct ext2_dir_entry_2 *) page_address(page);
  96                 dlimit = (char *)page_address(page) + PAGE_SIZE;
  97                 while ((char *) de < dlimit) {
  98                         /* this code is executed quadratically often */
  99                         /* do minimal checking `by hand' */
 100                         int de_len;
 101
 102                         if ((char *) de + namelen <= dlimit &&
 103                             ext2_match (namelen, name, de)) {
 104                                 /* found a match -
 105                                    just to be sure, do a full check */
 106 #if 0
 107                                 if (!ext2_check_dir_entry("ext2_find_entry",
 108                                                           dir, de, bh, offset))
 109                                         goto failure;
 110 #endif
 111                                 *res_dir = de;
 112                                 return page;
 113                         }
 114                         /* prevent looping on a bad block */
 115                         de_len = le16_to_cpu(de->rec_len);
 116                         if (de_len <= 0)
 117                                 goto failure;
 118                         offset += de_len;
 119                         de = (struct ext2_dir_entry_2 *)
 120                                 ((char *) de + de_len);
 121                 }
 122                 page_cache_release(page);
 123         }
 124
 125 failure:
 126         page_cache_release(page);
 127         return NULL;
 128 }
 129
 130 struct dentry *obdfs_lookup(struct inode * dir, struct dentry *dentry)
 131 {
 132         struct inode * inode;
 133         struct ext2_dir_entry_2 * de;
 134         struct page * page;
 135
 136         if (dentry->d_name.len > EXT2_NAME_LEN)
 137                 return ERR_PTR(-ENAMETOOLONG);
 138
 139         page = obdfs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
 140         inode = NULL;
 141         if (page) {
 142                 unsigned long ino = le32_to_cpu(de->inode);
 143                 page_cache_release(page);
 144                 inode = iget(dir->i_sb, ino);
 145
 146                 if (!inode)
 147                         return ERR_PTR(-EACCES);
 148         }
 149         d_add(dentry, inode);
 150         return NULL;
 151 }
 152
 153
 154 /*
 155  *      ext2_add_entry()
 156  *
 157  * adds a file entry to the specified directory, using the same
 158  * semantics as ext2_find_entry(). It returns NULL if it failed.
 159  *
 160  * NOTE!! The inode part of 'de' is left at 0 - which means you
 161  * may not sleep between calling this and putting something into
 162  * the entry, as someone else might have used it while you slept.
 163
 164  * returns a locked page
 165  */
 166 static struct page *obdfs_add_entry (struct inode * dir,
 167                                      const char * name, int namelen,
 168                                      struct ext2_dir_entry_2 ** res_dir,
 169                                      int *err)
 170 {
 171         unsigned long offset;
 172         unsigned short rec_len;
 173         struct page *page;
 174         struct ext2_dir_entry_2 * de, * de1;
 175         struct super_block * sb;
 176
 177         *err = -EINVAL;
 178         *res_dir = NULL;
 179         if (!dir || !dir->i_nlink)
 180                 return NULL;
 181         sb = dir->i_sb;
 182
 183         if (!namelen)
 184                 return NULL;
 185         /*
 186          * Is this a busy deleted directory?  Can't create new files if so
 187          */
 188         if (dir->i_size == 0)
 189         {
 190                 *err = -ENOENT;
 191                 return NULL;
 192         }
 193         page = obdfs_getpage(dir, 0, 0, LOCKED);
 194         if (!page)
 195                 return NULL;
 196         rec_len = EXT2_DIR_REC_LEN(namelen);
 197         offset = 0;
 198         de = (struct ext2_dir_entry_2 *) page_address(page);
 199         *err = -ENOSPC;
 200         while (1) {
 201                 if ((char *)de >= PAGE_SIZE + (char *)page_address(page)) {
 202                         UnlockPage(page);
 203                         page_cache_release(page);
 204                         page = obdfs_getpage(dir, offset, 1, LOCKED);
 205                         if (page)
 206                                 return NULL;
 207                         if (dir->i_size <= offset) {
 208                                 if (dir->i_size == 0) {
 209                                         *err = -ENOENT;
 210                                         return NULL;
 211                                 }
 212
 213                                 ext2_debug ("creating next block\n");
 214
 215                                 de = (struct ext2_dir_entry_2 *) page_address(page);
 216                                 de->inode = 0;
 217                                 de->rec_len = le16_to_cpu(sb->s_blocksize);
 218                                 dir->i_size = offset + PAGE_SIZE;
 219                                 dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 220                                 mark_inode_dirty(dir);
 221                         } else {
 222
 223                                 ext2_debug ("skipping to next block\n");
 224
 225                                 de = (struct ext2_dir_entry_2 *) page_address(page);
 226                         }
 227                 }
 228 #if 0
 229                 if (!ext2_check_dir_entry ("ext2_add_entry", dir, de, bh,
 230                                            offset)) {
 231                         *err = -ENOENT;
 232                         brelse (bh);
 233                         return NULL;
 234                 }
 235 #endif
 236                 if (ext2_match (namelen, name, de)) {
 237                                 *err = -EEXIST;
 238                                 UnlockPage(page);
 239                                 page_cache_release(page);
 240                                 return NULL;
 241                 }
 242                 if ((le32_to_cpu(de->inode) == 0 && le16_to_cpu(de->rec_len) >= rec_len) ||
 243                     (le16_to_cpu(de->rec_len) >= EXT2_DIR_REC_LEN(de->name_len) + rec_len)) {
 244                         offset += le16_to_cpu(de->rec_len);
 245                         if (le32_to_cpu(de->inode)) {
 246                                 de1 = (struct ext2_dir_entry_2 *) ((char *) de +
 247                                         EXT2_DIR_REC_LEN(de->name_len));
 248                                 de1->rec_len = cpu_to_le16(le16_to_cpu(de->rec_len) -
 249                                         EXT2_DIR_REC_LEN(de->name_len));
 250                                 de->rec_len = cpu_to_le16(EXT2_DIR_REC_LEN(de->name_len));
 251                                 de = de1;
 252                         }
 253                         de->inode = 0;
 254                         de->name_len = namelen;
 255                         de->file_type = 0;
 256                         memcpy (de->name, name, namelen);
 257                         /*
 258                          * XXX shouldn't update any times until successful
 259                          * completion of syscall, but too many callers depend
 260                          * on this.
 261                          *
 262                          * XXX similarly, too many callers depend on
 263                          * ext2_new_inode() setting the times, but error
 264                          * recovery deletes the inode, so the worst that can
 265                          * happen is that the times are slightly out of date
 266                          * and/or different from the directory change time.
 267                          */
 268                         dir->i_mtime = dir->i_ctime = CURRENT_TIME;
 269                         dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 270                         mark_inode_dirty(dir);
 271                         dir->i_version = ++event;
 272                         *res_dir = de;
 273                         *err = 0;
 274                         PDEBUG(page, "addentry");
 275                         return page;
 276                 }
 277                 offset += le16_to_cpu(de->rec_len);
 278                 de = (struct ext2_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
 279         }
 280
 281         UnlockPage(page);
 282         page_cache_release(page);
 283         PDEBUG(page, "addentry");
 284         EXIT;
 285         return NULL;
 286 }
 287
 288 /*
 289  * ext2_delete_entry deletes a directory entry by merging it with the
 290  * previous entry
 291  */
 292 static int obdfs_delete_entry (struct ext2_dir_entry_2 * dir,
 293                               struct page * page)
 294 {
 295         struct ext2_dir_entry_2 * de, * pde;
 296         int i;
 297
 298         i = 0;
 299         pde = NULL;
 300         de = (struct ext2_dir_entry_2 *) page_address(page);
 301         while (i < PAGE_SIZE) {
 302 #if 0
 303                 if (!ext2_check_dir_entry ("ext2_delete_entry", NULL,
 304                                            de, bh, i))
 305                         return -EIO;
 306 #endif
 307                 if (de == dir)  {
 308                         if (pde)
 309                                 pde->rec_len =
 310                                         cpu_to_le16(le16_to_cpu(pde->rec_len) +
 311                                                     le16_to_cpu(dir->rec_len));
 312                         else
 313                                 dir->inode = 0;
 314                         return 0;
 315                 }
 316                 i += le16_to_cpu(de->rec_len);
 317                 pde = de;
 318                 de = (struct ext2_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
 319         }
 320         return -ENOENT;
 321 }
 322
 323
 324 static inline void ext2_set_de_type(struct super_block *sb,
 325                                 struct ext2_dir_entry_2 *de,
 326                                 umode_t mode) {
 327         if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
 328                 return;
 329         if (S_ISCHR(mode))
 330                 de->file_type = EXT2_FT_CHRDEV;
 331         else if (S_ISBLK(mode))
 332                 de->file_type = EXT2_FT_BLKDEV;
 333         else if (S_ISFIFO(mode))
 334                 de->file_type = EXT2_FT_FIFO;
 335         else if (S_ISLNK(mode))
 336                 de->file_type = EXT2_FT_SYMLINK;
 337         else if (S_ISREG(mode))
 338                 de->file_type = EXT2_FT_REG_FILE;
 339         else if (S_ISDIR(mode))
 340                 de->file_type = EXT2_FT_DIR;
 341 }
 342
 343 /*
 344  * By the time this is called, we already have created
 345  * the directory cache entry for the new file, but it
 346  * is so far negative - it has no inode.
 347  *
 348  * If the create succeeds, we fill in the inode information
 349  * with d_instantiate().
 350  */
 351 int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
 352 {
 353         struct inode * inode;
 354         struct page *page;
 355         struct ext2_dir_entry_2 * de;
 356         int err = -EIO;
 357         struct obdfs_sb_info *sbi;
 358         ino_t ino;
 359
 360         ENTRY;
 361
 362         sbi = dir->i_sb->u.generic_sbp;
 363         /*
 364          * N.B. Several error exits in ext2_new_inode don't set err.
 365          */
 366         ino = sbi->osi_ops->o_create(sbi->osi_obd, 0, &err);
 367         if ( ino == -1 )
 368                 return -1;
 369         inode =  iget(dir->i_sb, ino);
 370         if (!inode)
 371                 return err;
 372
 373         inode->i_op = &obdfs_inode_ops;
 374         inode->i_mode = mode;
 375         mark_inode_dirty(inode);
 376         page = obdfs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
 377         if (!page) {
 378                 inode->i_nlink--;
 379                 mark_inode_dirty(inode);
 380                 iput (inode);
 381                 return err;
 382         }
 383         de->inode = cpu_to_le32(inode->i_ino);
 384         ext2_set_de_type(dir->i_sb, de, S_IFREG);
 385         dir->i_version = ++event;
 386         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 387                             dir->i_ino, page, 0);
 388         UnlockPage(page);
 389 #if 0
 390         if (IS_SYNC(dir)) {
 391                 ll_rw_block (WRITE, 1, &bh);
 392                 wait_on_buffer (bh);
 393         }
 394 #endif
 395         page_cache_release(page);
 396         d_instantiate(dentry, inode);
 397         return 0;
 398 }
 399
 400 int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
 401 {
 402         struct inode * inode;
 403         struct page *page;
 404         struct ext2_dir_entry_2 * de;
 405         int err = -EIO;
 406         struct obdfs_sb_info *sbi;
 407
 408         ino_t ino;
 409
 410         ENTRY;
 411
 412         sbi = dir->i_sb->u.generic_sbp;
 413         /*
 414          * N.B. Several error exits in ext2_new_inode don't set err.
 415          */
 416         ino = sbi->osi_ops->o_create(sbi->osi_obd, 0, &err);
 417         if ( ino == -1 )
 418                 return -1;
 419         inode =  iget(dir->i_sb, ino);
 420         if (!inode)
 421                 return err;
 422
 423         inode->i_uid = current->fsuid;
 424         init_special_inode(inode, mode, rdev);
 425         page = obdfs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
 426         if (!page)
 427                 goto out_no_entry;
 428         de->inode = cpu_to_le32(inode->i_ino);
 429         dir->i_version = ++event;
 430         ext2_set_de_type(dir->i_sb, de, inode->i_mode);
 431         mark_inode_dirty(inode);
 432         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 433                             dir->i_ino, page, 0);
 434         UnlockPage(page);
 435
 436 #if 0
 437         if (IS_SYNC(dir)) {
 438                 ll_rw_block (WRITE, 1, &bh);
 439                 wait_on_buffer (bh);
 440         }
 441 #endif
 442         d_instantiate(dentry, inode);
 443         page_cache_release(page);
 444         err = 0;
 445 out:
 446         return err;
 447
 448 out_no_entry:
 449         inode->i_nlink--;
 450         mark_inode_dirty(inode);
 451         iput(inode);
 452         goto out;
 453 }
 454
 455 int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
 456 {
 457         struct inode * child;
 458         struct page *page, *child_page;
 459         struct ext2_dir_entry_2 * de;
 460         struct obdfs_sb_info *sbi;
 461         int err;
 462         ino_t ino;
 463
 464         ENTRY;
 465         sbi = dir->i_sb->u.generic_sbp;
 466
 467         err = -EMLINK;
 468         if (dir->i_nlink >= EXT2_LINK_MAX)
 469                 goto out;
 470
 471         err = -EIO;
 472         ino = iops(dir)->o_create(sbi->osi_obd, 0, &err);
 473         if ( ino == -1 )
 474                 return -1;
 475         child =  iget(dir->i_sb, ino);
 476         if (!child)
 477                 return err;
 478
 479
 480         child->i_op = &obdfs_inode_ops;
 481         child->i_size = PAGE_SIZE;
 482         child->i_blocks = 0;
 483         child_page = obdfs_getpage(child, 0, 1, LOCKED);
 484         if (!child_page) {
 485                 child->i_nlink--; /* is this nlink == 0? */
 486                 mark_inode_dirty(child);
 487                 iput (child);
 488                 return err;
 489         }
 490         child->i_blocks = PAGE_SIZE/child->i_sb->s_blocksize;
 491
 492         /* create . and .. */
 493         de = (struct ext2_dir_entry_2 *) page_address(child_page);
 494         de->inode = cpu_to_le32(child->i_ino);
 495         de->name_len = 1;
 496         de->rec_len = cpu_to_le16(EXT2_DIR_REC_LEN(de->name_len));
 497         strcpy (de->name, ".");
 498         ext2_set_de_type(dir->i_sb, de, S_IFDIR);
 499
 500         de = (struct ext2_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
 501         de->inode = cpu_to_le32(dir->i_ino);
 502         de->rec_len = cpu_to_le16(child->i_sb->s_blocksize - EXT2_DIR_REC_LEN(1));
 503         de->name_len = 2;
 504         strcpy (de->name, "..");
 505         ext2_set_de_type(dir->i_sb, de, S_IFDIR);
 506
 507         iops(dir)->o_brw(WRITE, sbi->osi_conn_info.conn_id, child->i_ino, child_page, 1);
 508         UnlockPage(child_page);
 509         page_cache_release(child_page);
 510
 511         child->i_nlink = 2;
 512         child->i_mode = S_IFDIR | mode;
 513         if (dir->i_mode & S_ISGID)
 514                 child->i_mode |= S_ISGID;
 515         mark_inode_dirty(child);
 516
 517         /* now deal with the parent */
 518         page = obdfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
 519         if (!page) {
 520                 goto out_no_entry;
 521         }
 522
 523         de->inode = cpu_to_le32(child->i_ino);
 524         ext2_set_de_type(dir->i_sb, de, S_IFDIR);
 525         dir->i_version = ++event;
 526
 527 #if 0
 528         if (IS_SYNC(dir)) {
 529                 ll_rw_block (WRITE, 1, &bh);
 530                 wait_on_buffer (bh);
 531         }
 532 #endif
 533         dir->i_nlink++;
 534         dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 535         mark_inode_dirty(dir);
 536         iops(dir)->o_brw(WRITE, sbi->osi_conn_info.conn_id, dir->i_ino, page, 1);
 537         UnlockPage(page);
 538         page_cache_release(page);
 539         d_instantiate(dentry, child);
 540         err = 0;
 541 out:
 542         EXIT;
 543         return err;
 544
 545 out_no_entry:
 546         child->i_nlink = 0;
 547         mark_inode_dirty(child);
 548         iput (child);
 549         goto out;
 550 }
 551
 552
 553 /*
 554  * routine to check that the specified directory is empty (for rmdir)
 555  */
 556 static int empty_dir (struct inode * inode)
 557 {
 558         unsigned long offset;
 559         struct page *page;
 560         struct ext2_dir_entry_2 * de, * de1;
 561         struct super_block * sb;
 562
 563         sb = inode->i_sb;
 564         if (inode->i_size < EXT2_DIR_REC_LEN(1) + EXT2_DIR_REC_LEN(2) ||
 565             !(page = obdfs_getpage (inode, 0, 0, NOLOCK))) {
 566                 ext2_warning (inode->i_sb, "empty_dir",
 567                               "bad directory (dir #%lu) - no data block",
 568                               inode->i_ino);
 569                 return 1;
 570         }
 571         de = (struct ext2_dir_entry_2 *) page_address(page);
 572         de1 = (struct ext2_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
 573         if (le32_to_cpu(de->inode) != inode->i_ino || !le32_to_cpu(de1->inode) ||
 574             strcmp (".", de->name) || strcmp ("..", de1->name)) {
 575                 ext2_warning (inode->i_sb, "empty_dir",
 576                               "bad directory (dir #%lu) - no `.' or `..'",
 577                               inode->i_ino);
 578                 page_cache_release(page);
 579                 return 1;
 580         }
 581         offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
 582         de = (struct ext2_dir_entry_2 *) ((char *) de1 + le16_to_cpu(de1->rec_len));
 583         while (offset < inode->i_size ) {
 584                 if (!page || (void *) de >= (void *) (page_address(page) + PAGE_SIZE)) {
 585                         if (page)
 586                                 page_cache_release(page);
 587                         page = obdfs_getpage(inode, offset, 0, NOLOCK);
 588                         if (!page) {
 589 #if 0
 590                                 ext2_error (sb, "empty_dir",
 591                                             "directory #%lu contains a hole at offset %lu",
 592                                             inode->i_ino, offset);
 593 #endif
 594                                 offset += sb->s_blocksize;
 595                                 continue;
 596                         }
 597                         de = (struct ext2_dir_entry_2 *) page_address(page);
 598                 }
 599 #if 0
 600                 if (!ext2_check_dir_entry ("empty_dir", inode, de, bh,
 601                                            offset)) {
 602                         brelse (bh);
 603                         return 1;
 604                 }
 605 #endif
 606                 if (le32_to_cpu(de->inode)) {
 607                         page_cache_release(page);
 608                         return 0;
 609                 }
 610                 offset += le16_to_cpu(de->rec_len);
 611                 de = (struct ext2_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
 612         }
 613         page_cache_release(page);
 614         return 1;
 615 }
 616
 617 int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
 618 {
 619         int retval;
 620         struct inode * inode;
 621         struct page *page;
 622         struct ext2_dir_entry_2 * de;
 623         struct obdfs_sb_info *sbi;
 624
 625         ENTRY;
 626         sbi = dir->i_sb->u.generic_sbp;
 627
 628         retval = -ENOENT;
 629         page = obdfs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
 630         if (!page)
 631                 goto end_rmdir;
 632
 633         inode = dentry->d_inode;
 634         DQUOT_INIT(inode);
 635
 636         retval = -EIO;
 637         if (le32_to_cpu(de->inode) != inode->i_ino)
 638                 goto end_rmdir;
 639
 640         retval = -ENOTEMPTY;
 641         if (!empty_dir (inode))
 642                 goto end_rmdir;
 643
 644         retval = obdfs_delete_entry (de, page);
 645         dir->i_version = ++event;
 646         if (retval)
 647                 goto end_rmdir;
 648         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 649                             dir->i_ino, page, 0);
 650         UnlockPage(page);
 651 #if 0
 652         if (IS_SYNC(dir)) {
 653                 ll_rw_block (WRITE, 1, &bh);
 654                 wait_on_buffer (bh);
 655         }
 656 #endif
 657         if (inode->i_nlink != 2)
 658                 ext2_warning (inode->i_sb, "ext2_rmdir",
 659                               "empty directory has nlink!=2 (%d)",
 660                               inode->i_nlink);
 661         inode->i_version = ++event;
 662         inode->i_nlink = 0;
 663         inode->i_size = 0;
 664         mark_inode_dirty(inode);
 665         dir->i_nlink--;
 666         inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
 667         dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 668         mark_inode_dirty(dir);
 669         d_delete(dentry);
 670
 671 end_rmdir:
 672         if ( page )
 673                 page_cache_release(page);
 674         return retval;
 675 }
 676
 677 int obdfs_unlink(struct inode * dir, struct dentry *dentry)
 678 {
 679         int retval;
 680         struct inode * inode;
 681         struct page *page;
 682         struct ext2_dir_entry_2 * de;
 683         struct obdfs_sb_info *sbi;
 684
 685         ENTRY;
 686         sbi = dir->i_sb->u.generic_sbp;
 687
 688         retval = -ENOENT;
 689         page = obdfs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
 690         if (!page)
 691                 goto end_unlink;
 692
 693         inode = dentry->d_inode;
 694         DQUOT_INIT(inode);
 695
 696         retval = -EIO;
 697         if (le32_to_cpu(de->inode) != inode->i_ino)
 698                 goto end_unlink;
 699
 700         if (!inode->i_nlink) {
 701                 ext2_warning (inode->i_sb, "ext2_unlink",
 702                               "Deleting nonexistent file (%lu), %d",
 703                               inode->i_ino, inode->i_nlink);
 704                 inode->i_nlink = 1;
 705         }
 706         retval = obdfs_delete_entry (de, page);
 707         if (retval)
 708                 goto end_unlink;
 709         dir->i_version = ++event;
 710         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 711                             dir->i_ino, page, 0);
 712         UnlockPage(page);
 713 #if 0
 714         if (IS_SYNC(dir)) {
 715                 ll_rw_block (WRITE, 1, &bh);
 716                 wait_on_buffer (bh);
 717         }
 718 #endif
 719         dir->i_ctime = dir->i_mtime = CURRENT_TIME;
 720         dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 721         mark_inode_dirty(dir);
 722         inode->i_nlink--;
 723         mark_inode_dirty(inode);
 724         inode->i_ctime = dir->i_ctime;
 725         retval = 0;
 726         d_delete(dentry);       /* This also frees the inode */
 727
 728 end_unlink:
 729         if (page)
 730                 page_cache_release(page);
 731         return retval;
 732 }
 733
 734 int obdfs_symlink (struct inode * dir, struct dentry *dentry, const char * symname)
 735 {
 736         struct ext2_dir_entry_2 * de;
 737         struct inode * inode;
 738         struct page* page = NULL, * name_page = NULL;
 739         char * link;
 740         int i, l, err = -EIO;
 741         char c;
 742         struct obdfs_sb_info *sbi;
 743         ino_t ino;
 744
 745         ENTRY;
 746
 747         sbi = dir->i_sb->u.generic_sbp;
 748         /*
 749          * N.B. Several error exits in ext2_new_inode don't set err.
 750          */
 751         ino = sbi->osi_ops->o_create(sbi->osi_obd, 0, &err);
 752         if ( ino == -1 )
 753                 return -1;
 754         inode =  iget(dir->i_sb, ino);
 755         if (!inode)
 756                 return err;
 757
 758         inode->i_mode = S_IFLNK | S_IRWXUGO;
 759         inode->i_op = &obdfs_inode_ops;
 760         for (l = 0; l < inode->i_sb->s_blocksize - 1 &&
 761              symname [l]; l++)
 762                 ;
 763         if (l >= sizeof (inode->u.ext2_i.i_data)) {
 764
 765                 ext2_debug ("l=%d, normal symlink\n", l);
 766
 767                 name_page = obdfs_getpage(inode, 0, 1, LOCKED);
 768                 if (!name_page) {
 769                         inode->i_nlink--;
 770                         mark_inode_dirty(inode);
 771                         iput (inode);
 772                         return err;
 773                 }
 774                 link = (char *)page_address(name_page);
 775         } else {
 776                 link = (char *) inode->u.ext2_i.i_data;
 777
 778                 ext2_debug ("l=%d, fast symlink\n", l);
 779
 780         }
 781         i = 0;
 782         while (i < inode->i_sb->s_blocksize - 1 && (c = *(symname++)))
 783                 link[i++] = c;
 784         link[i] = 0;
 785         if (name_page) {
 786                 sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 787                                     inode->i_ino, name_page, 1);
 788                 PDEBUG(name_page, "symlink");
 789                 UnlockPage(name_page);
 790                 page_cache_release(name_page);
 791         }
 792         inode->i_size = i;
 793         mark_inode_dirty(inode);
 794
 795         page = obdfs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
 796         if (!page)
 797                 goto out_no_entry;
 798         de->inode = cpu_to_le32(inode->i_ino);
 799         ext2_set_de_type(dir->i_sb, de, S_IFLNK);
 800         dir->i_version = ++event;
 801         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 802                             dir->i_ino, page, 1);
 803         UnlockPage(page);
 804 #if 0
 805         if (IS_SYNC(dir)) {
 806                 ll_rw_block (WRITE, 1, &bh);
 807                 wait_on_buffer (bh);
 808         }
 809 #endif
 810         d_instantiate(dentry, inode);
 811         err = 0;
 812 out:
 813         return err;
 814
 815 out_no_entry:
 816         inode->i_nlink--;
 817         mark_inode_dirty(inode);
 818         iput (inode);
 819         goto out;
 820 }
 821
 822 int obdfs_link (struct dentry * old_dentry,
 823                 struct inode * dir, struct dentry *dentry)
 824 {
 825         struct inode *inode = old_dentry->d_inode;
 826         struct ext2_dir_entry_2 * de;
 827         struct page *page;
 828         int err;
 829         struct obdfs_sb_info *sbi;
 830
 831         ENTRY;
 832         sbi = dir->i_sb->u.generic_sbp;
 833
 834         if (S_ISDIR(inode->i_mode))
 835                 return -EPERM;
 836
 837         if (inode->i_nlink >= EXT2_LINK_MAX)
 838                 return -EMLINK;
 839
 840         page = obdfs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
 841         if (!page)
 842                 return err;
 843
 844         de->inode = cpu_to_le32(inode->i_ino);
 845         ext2_set_de_type(dir->i_sb, de, inode->i_mode);
 846         dir->i_version = ++event;
 847         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 848                             dir->i_ino, page, 0);
 849         UnlockPage(page);
 850
 851 #if 0
 852         if (IS_SYNC(dir)) {
 853                 ll_rw_block (WRITE, 1, &bh);
 854                 wait_on_buffer (bh);
 855         }
 856 #endif
 857         page_cache_release(page);
 858         inode->i_nlink++;
 859         inode->i_ctime = CURRENT_TIME;
 860         mark_inode_dirty(inode);
 861         inode->i_count++;
 862         d_instantiate(dentry, inode);
 863         return 0;
 864 }
 865
 866 #define PARENT_INO(buffer) \
 867         ((struct ext2_dir_entry_2 *) ((char *) buffer + \
 868         le16_to_cpu(((struct ext2_dir_entry_2 *) buffer)->rec_len)))->inode
 869
 870 /*
 871  * Anybody can rename anything with this: the permission checks are left to the
 872  * higher-level routines.
 873  */
 874 int obdfs_rename (struct inode * old_dir, struct dentry *old_dentry,
 875                            struct inode * new_dir,struct dentry *new_dentry)
 876 {
 877         struct inode * old_inode, * new_inode;
 878         struct page * old_page, * new_page, * dir_page;
 879         struct ext2_dir_entry_2 * old_de, * new_de;
 880         int retval;
 881         struct obdfs_sb_info *sbi;
 882
 883         ENTRY;
 884         sbi = old_dir->i_sb->u.generic_sbp;
 885
 886         new_page = dir_page = NULL;
 887
 888         old_page = obdfs_find_entry (old_dir, old_dentry->d_name.name, old_dentry->d_name.len, &old_de);
 889         /*
 890          *  Check for inode number is _not_ due to possible IO errors.
 891          *  We might rmdir the source, keep it as pwd of some process
 892          *  and merrily kill the link to whatever was created under the
 893          *  same name. Goodbye sticky bit ;-<
 894          */
 895         old_inode = old_dentry->d_inode;
 896         retval = -ENOENT;
 897         if (!old_page || le32_to_cpu(old_de->inode) != old_inode->i_ino)
 898                 goto end_rename;
 899
 900         new_inode = new_dentry->d_inode;
 901         new_page = obdfs_find_entry (new_dir, new_dentry->d_name.name,
 902                                 new_dentry->d_name.len, &new_de);
 903         if (new_page) {
 904                 if (!new_inode) {
 905                         page_cache_release(new_page);
 906                         new_page = NULL;
 907                 } else {
 908                         DQUOT_INIT(new_inode);
 909                 }
 910         }
 911         if (S_ISDIR(old_inode->i_mode)) {
 912                 if (new_inode) {
 913                         retval = -ENOTEMPTY;
 914                         if (!empty_dir (new_inode))
 915                                 goto end_rename;
 916                 }
 917                 retval = -EIO;
 918                 dir_page= obdfs_getpage (old_inode, 0, 0, LOCKED);
 919                 if (!dir_page)
 920                         goto end_rename;
 921                 if (le32_to_cpu(PARENT_INO(page_address(dir_page))) != old_dir->i_ino)
 922                         goto end_rename;
 923                 retval = -EMLINK;
 924                 if (!new_inode && new_dir!=old_dir &&
 925                                 new_dir->i_nlink >= EXT2_LINK_MAX)
 926                         goto end_rename;
 927         }
 928         if (!new_page) {
 929                 new_page = obdfs_add_entry (new_dir, new_dentry->d_name.name,
 930                                         new_dentry->d_name.len, &new_de,
 931                                         &retval);
 932                 if (!new_page)
 933                         goto end_rename;
 934         }
 935         new_dir->i_version = ++event;
 936
 937         /*
 938          * ok, that's it
 939          */
 940         new_de->inode = le32_to_cpu(old_inode->i_ino);
 941         if (EXT2_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
 942                                       EXT2_FEATURE_INCOMPAT_FILETYPE))
 943                 new_de->file_type = old_de->file_type;
 944
 945         obdfs_delete_entry (old_de, old_page);
 946
 947         old_dir->i_version = ++event;
 948         if (new_inode) {
 949                 new_inode->i_nlink--;
 950                 new_inode->i_ctime = CURRENT_TIME;
 951                 mark_inode_dirty(new_inode);
 952         }
 953         old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
 954         old_dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 955         mark_inode_dirty(old_dir);
 956         if (dir_page) {
 957                 PARENT_INO(page_address(dir_page)) = le32_to_cpu(new_dir->i_ino);
 958                 sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 959                             new_dir->i_ino, dir_page, 0);
 960                 old_dir->i_nlink--;
 961                 mark_inode_dirty(old_dir);
 962                 if (new_inode) {
 963                         new_inode->i_nlink--;
 964                         mark_inode_dirty(new_inode);
 965                 } else {
 966                         new_dir->i_nlink++;
 967                         new_dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
 968                         mark_inode_dirty(new_dir);
 969                 }
 970         }
 971         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 972                             old_inode->i_ino, old_page, 0);
 973 #if 0
 974         if (IS_SYNC(old_dir)) {
 975                 ll_rw_block (WRITE, 1, &old_bh);
 976                 wait_on_buffer (old_bh);
 977         }
 978 #endif
 979         sbi->osi_ops->o_brw(WRITE, sbi->osi_conn_info.conn_id,
 980                             new_inode->i_ino, new_page, 0);
 981 #if 0
 982         if (IS_SYNC(new_dir)) {
 983                 ll_rw_block (WRITE, 1, &new_bh);
 984                 wait_on_buffer (new_bh);
 985         }
 986 #endif
 987
 988         retval = 0;
 989
 990 end_rename:
 991         if (old_page)
 992                 page_cache_release(old_page);
 993         if (new_page)
 994                 page_cache_release(new_page);
 995         if (dir_page)
 996                 page_cache_release(dir_page);
 997         return retval;
 998 }