lustre/kernel_patches/patches/vfs_intent-2.4.20-rh.patch

   1  fs/dcache.c               |   19 ++
   2  fs/exec.c                 |   17 +-
   3  fs/namei.c                |  333 ++++++++++++++++++++++++++++++++++++++--------
   4  fs/namespace.c            |   28 ++-
   5  fs/open.c                 |  176 +++++++++++++++++-------
   6  fs/proc/base.c            |    3
   7  fs/stat.c                 |   28 ++-
   8  include/linux/dcache.h    |   60 ++++++++
   9  include/linux/fs.h        |   32 ++++
  10  include/linux/fs_struct.h |    4
  11  kernel/exit.c             |    3
  12  kernel/fork.c             |    3
  13  kernel/ksyms.c            |    1
  14  13 files changed, 578 insertions(+), 129 deletions(-)
  15
  16 Index: linux-2.4.20/fs/dcache.c
  17 ===================================================================
  18 --- linux-2.4.20.orig/fs/dcache.c       Wed Mar 17 13:57:05 2004
  19 +++ linux-2.4.20/fs/dcache.c    Wed Mar 17 13:57:11 2004
  20 @@ -186,6 +186,13 @@
  21                 spin_unlock(&dcache_lock);
  22                 return 0;
  23         }
  24 +
  25 +       /* network invalidation by Lustre */
  26 +       if (dentry->d_flags & DCACHE_LUSTRE_INVALID) {
  27 +               spin_unlock(&dcache_lock);
  28 +               return 0;
  29 +       }
  30 +
  31         /*
  32          * Check whether to do a partial shrink_dcache
  33          * to get rid of unused child entries.
  34 @@ -841,13 +848,19 @@
  35   * Adds a dentry to the hash according to its name.
  36   */
  37
  38 -void d_rehash(struct dentry * entry)
  39 +void __d_rehash(struct dentry * entry, int lock)
  40  {
  41         struct list_head *list = d_hash(entry->d_parent, entry->d_name.hash);
  42         if (!list_empty(&entry->d_hash)) BUG();
  43 -       spin_lock(&dcache_lock);
  44 +       if (lock) spin_lock(&dcache_lock);
  45         list_add(&entry->d_hash, list);
  46 -       spin_unlock(&dcache_lock);
  47 +       if (lock) spin_unlock(&dcache_lock);
  48 +}
  49 +EXPORT_SYMBOL(__d_rehash);
  50 +
  51 +void d_rehash(struct dentry * entry)
  52 +{
  53 +       __d_rehash(entry, 1);
  54  }
  55
  56  #define do_switch(x,y) do { \
  57 Index: linux-2.4.20/fs/exec.c
  58 ===================================================================
  59 --- linux-2.4.20.orig/fs/exec.c Wed Mar 17 13:57:05 2004
  60 +++ linux-2.4.20/fs/exec.c      Wed Mar 17 13:57:11 2004
  61 @@ -114,8 +114,10 @@
  62         struct file * file;
  63         struct nameidata nd;
  64         int error;
  65 +       struct lookup_intent it = { .it_op = IT_OPEN,
  66 +                                   .it_flags = FMODE_READ|FMODE_EXEC };
  67
  68 -       error = user_path_walk(library, &nd);
  69 +       error = user_path_walk_it(library, &nd, &it);
  70         if (error)
  71                 goto out;
  72
  73 @@ -127,7 +129,8 @@
  74         if (error)
  75                 goto exit;
  76
  77 -       file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
  78 +       file = dentry_open_it(nd.dentry, nd.mnt, O_RDONLY, &it);
  79 +       intent_release(&it);
  80         error = PTR_ERR(file);
  81         if (IS_ERR(file))
  82                 goto out;
  83 @@ -382,8 +385,10 @@
  84         struct inode *inode;
  85         struct file *file;
  86         int err = 0;
  87 +       struct lookup_intent it = { .it_op = IT_OPEN,
  88 +                                   .it_flags = FMODE_READ|FMODE_EXEC };
  89
  90 -       err = path_lookup(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd);
  91 +       err = path_lookup_it(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd, &it);
  92         file = ERR_PTR(err);
  93         if (!err) {
  94                 inode = nd.dentry->d_inode;
  95 @@ -395,7 +400,8 @@
  96                                 err = -EACCES;
  97                         file = ERR_PTR(err);
  98                         if (!err) {
  99 -                               file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
 100 +                               file = dentry_open_it(nd.dentry, nd.mnt, O_RDONLY, &it);
 101 +                               intent_release(&it);
 102                                 if (!IS_ERR(file)) {
 103                                         err = deny_write_access(file);
 104                                         if (err) {
 105 @@ -407,6 +413,7 @@
 106                                 return file;
 107                         }
 108                 }
 109 +               intent_release(&it);
 110                 path_release(&nd);
 111         }
 112         goto out;
 113 @@ -1296,7 +1303,7 @@
 114                 goto close_fail;
 115         if (!file->f_op->write)
 116                 goto close_fail;
 117 -       if (do_truncate(file->f_dentry, 0) != 0)
 118 +       if (do_truncate(file->f_dentry, 0, 0) != 0)
 119                 goto close_fail;
 120
 121         retval = binfmt->core_dump(signr, regs, file);
 122 Index: linux-2.4.20/fs/namei.c
 123 ===================================================================
 124 --- linux-2.4.20.orig/fs/namei.c        Wed Mar 17 13:57:03 2004
 125 +++ linux-2.4.20/fs/namei.c     Wed Mar 17 13:58:01 2004
 126 @@ -94,6 +94,13 @@
 127   * XEmacs seems to be relying on it...
 128   */
 129
 130 +void intent_release(struct lookup_intent *it)
 131 +{
 132 +       if (it && it->it_op_release)
 133 +               it->it_op_release(it);
 134 +
 135 +}
 136 +
 137  /* In order to reduce some races, while at the same time doing additional
 138   * checking and hopefully speeding things up, we copy filenames to the
 139   * kernel data space before using them..
 140 @@ -260,10 +267,19 @@
 141   * Internal lookup() using the new generic dcache.
 142   * SMP-safe
 143   */
 144 -static struct dentry * cached_lookup(struct dentry * parent, struct qstr * name, int flags)
 145 +static struct dentry *cached_lookup(struct dentry *parent, struct qstr *name,
 146 +                                   int flags, struct lookup_intent *it)
 147  {
 148         struct dentry * dentry = d_lookup(parent, name);
 149
 150 +       if (dentry && dentry->d_op && dentry->d_op->d_revalidate_it) {
 151 +               if (!dentry->d_op->d_revalidate_it(dentry, flags, it) &&
 152 +                   !d_invalidate(dentry)) {
 153 +                       dput(dentry);
 154 +                       dentry = NULL;
 155 +               }
 156 +               return dentry;
 157 +       } else
 158         if (dentry && dentry->d_op && dentry->d_op->d_revalidate) {
 159                 if (!dentry->d_op->d_revalidate(dentry, flags) && !d_invalidate(dentry)) {
 160                         dput(dentry);
 161 @@ -281,11 +297,15 @@
 162   * make sure that nobody added the entry to the dcache in the meantime..
 163   * SMP-safe
 164   */
 165 -static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, int flags)
 166 +static struct dentry *real_lookup(struct dentry *parent, struct qstr *name,
 167 +                                 int flags, struct lookup_intent *it)
 168  {
 169         struct dentry * result;
 170         struct inode *dir = parent->d_inode;
 171 +       int counter = 0;
 172
 173 +again:
 174 +       counter++;
 175         down(&dir->i_sem);
 176         /*
 177          * First re-do the cached lookup just in case it was created
 178 @@ -300,6 +320,9 @@
 179                 result = ERR_PTR(-ENOMEM);
 180                 if (dentry) {
 181                         lock_kernel();
 182 +                       if (dir->i_op->lookup_it)
 183 +                               result = dir->i_op->lookup_it(dir, dentry, it, flags);
 184 +                       else
 185                         result = dir->i_op->lookup(dir, dentry);
 186                         unlock_kernel();
 187                         if (result)
 188 @@ -321,6 +344,15 @@
 189                         dput(result);
 190                         result = ERR_PTR(-ENOENT);
 191                 }
 192 +       } else if (result->d_op && result->d_op->d_revalidate_it) {
 193 +               if (!result->d_op->d_revalidate_it(result, flags, it) &&
 194 +                   !d_invalidate(result)) {
 195 +                       dput(result);
 196 +                       if (counter > 10)
 197 +                               result = ERR_PTR(-ESTALE);
 198 +                       if (!IS_ERR(result))
 199 +                               goto again;
 200 +               }
 201         }
 202         return result;
 203  }
 204 @@ -334,7 +366,8 @@
 205   * Without that kind of total limit, nasty chains of consecutive
 206   * symlinks can cause almost arbitrarily long lookups.
 207   */
 208 -static inline int do_follow_link(struct dentry *dentry, struct nameidata *nd)
 209 +static inline int do_follow_link(struct dentry *dentry, struct nameidata *nd,
 210 +                                struct lookup_intent *it)
 211  {
 212         int err;
 213         if (current->link_count >= max_recursive_link)
 214 @@ -348,10 +381,18 @@
 215         current->link_count++;
 216         current->total_link_count++;
 217         UPDATE_ATIME(dentry->d_inode);
 218 +       nd->intent = it;
 219         err = dentry->d_inode->i_op->follow_link(dentry, nd);
 220 +       if (!err && it != NULL && !(it->d.lustre.it_int_flags & IT_FL_FOLLOWED)) {
 221 +               /* vfs_follow_link was never called */
 222 +               intent_release(it);
 223 +               path_release(nd);
 224 +               err = -ENOLINK;
 225 +       }
 226         current->link_count--;
 227         return err;
 228  loop:
 229 +       intent_release(it);
 230         path_release(nd);
 231         return -ELOOP;
 232  }
 233 @@ -381,15 +422,26 @@
 234         return __follow_up(mnt, dentry);
 235  }
 236
 237 -static inline int __follow_down(struct vfsmount **mnt, struct dentry **dentry)
 238 +static inline int __follow_down(struct vfsmount **mnt, struct dentry **dentry,
 239 +                               struct lookup_intent *it)
 240  {
 241         struct vfsmount *mounted;
 242
 243         spin_lock(&dcache_lock);
 244         mounted = lookup_mnt(*mnt, *dentry);
 245         if (mounted) {
 246 +               int opc = 0, mode = 0;
 247                 *mnt = mntget(mounted);
 248                 spin_unlock(&dcache_lock);
 249 +               if (it) {
 250 +                       opc = it->it_op;
 251 +                       mode = it->it_create_mode;
 252 +               }
 253 +               intent_release(it);
 254 +               if (it) {
 255 +                       it->it_op = opc;
 256 +                       it->it_create_mode = mode;
 257 +               }
 258                 dput(*dentry);
 259                 mntput(mounted->mnt_parent);
 260                 *dentry = dget(mounted->mnt_root);
 261 @@ -401,7 +453,7 @@
 262
 263  int follow_down(struct vfsmount **mnt, struct dentry **dentry)
 264  {
 265 -       return __follow_down(mnt,dentry);
 266 +       return __follow_down(mnt, dentry, NULL);
 267  }
 268
 269  static inline void follow_dotdot(struct nameidata *nd)
 270 @@ -437,7 +489,7 @@
 271                 mntput(nd->mnt);
 272                 nd->mnt = parent;
 273         }
 274 -       while (d_mountpoint(nd->dentry) && __follow_down(&nd->mnt, &nd->dentry))
 275 +       while (d_mountpoint(nd->dentry) && __follow_down(&nd->mnt, &nd->dentry, NULL))
 276                 ;
 277  }
 278
 279 @@ -449,7 +501,8 @@
 280   *
 281   * We expect 'base' to be positive and a directory.
 282   */
 283 -int link_path_walk(const char * name, struct nameidata *nd)
 284 +int link_path_walk_it(const char *name, struct nameidata *nd,
 285 +                     struct lookup_intent *it)
 286  {
 287         struct dentry *dentry;
 288         struct inode *inode;
 289 @@ -526,18 +579,18 @@
 290                                 break;
 291                 }
 292                 /* This does the actual lookups.. */
 293 -               dentry = cached_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
 294 +               dentry = cached_lookup(nd->dentry, &this, LOOKUP_CONTINUE, NULL);
 295                 if (!dentry) {
 296                         err = -EWOULDBLOCKIO;
 297                         if (atomic)
 298                                 break;
 299 -                       dentry = real_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
 300 +                       dentry = real_lookup(nd->dentry, &this, LOOKUP_CONTINUE, NULL);
 301                         err = PTR_ERR(dentry);
 302                         if (IS_ERR(dentry))
 303                                 break;
 304                 }
 305                 /* Check mountpoints.. */
 306 -               while (d_mountpoint(dentry) && __follow_down(&nd->mnt, &dentry))
 307 +               while (d_mountpoint(dentry) && __follow_down(&nd->mnt, &dentry, NULL))
 308                         ;
 309
 310                 err = -ENOENT;
 311 @@ -549,7 +601,7 @@
 312                         goto out_dput;
 313
 314                 if (inode->i_op->follow_link) {
 315 -                       err = do_follow_link(dentry, nd);
 316 +                       err = do_follow_link(dentry, nd, NULL);
 317                         dput(dentry);
 318                         if (err)
 319                                 goto return_err;
 320 @@ -565,7 +617,7 @@
 321                         nd->dentry = dentry;
 322                 }
 323                 err = -ENOTDIR;
 324 -               if (!inode->i_op->lookup)
 325 +               if (!inode->i_op->lookup && !inode->i_op->lookup_it)
 326                         break;
 327                 continue;
 328                 /* here ends the main loop */
 329 @@ -592,22 +644,22 @@
 330                         if (err < 0)
 331                                 break;
 332                 }
 333 -               dentry = cached_lookup(nd->dentry, &this, 0);
 334 +               dentry = cached_lookup(nd->dentry, &this, 0, it);
 335                 if (!dentry) {
 336                         err = -EWOULDBLOCKIO;
 337                         if (atomic)
 338                                 break;
 339 -                       dentry = real_lookup(nd->dentry, &this, 0);
 340 +                       dentry = real_lookup(nd->dentry, &this, 0, it);
 341                         err = PTR_ERR(dentry);
 342                         if (IS_ERR(dentry))
 343                                 break;
 344                 }
 345 -               while (d_mountpoint(dentry) && __follow_down(&nd->mnt, &dentry))
 346 +               while (d_mountpoint(dentry) && __follow_down(&nd->mnt, &dentry, it))
 347                         ;
 348                 inode = dentry->d_inode;
 349                 if ((lookup_flags & LOOKUP_FOLLOW)
 350                     && inode && inode->i_op && inode->i_op->follow_link) {
 351 -                       err = do_follow_link(dentry, nd);
 352 +                       err = do_follow_link(dentry, nd, it);
 353                         dput(dentry);
 354                         if (err)
 355                                 goto return_err;
 356 @@ -621,7 +673,8 @@
 357                         goto no_inode;
 358                 if (lookup_flags & LOOKUP_DIRECTORY) {
 359                         err = -ENOTDIR;
 360 -                       if (!inode->i_op || !inode->i_op->lookup)
 361 +                       if (!inode->i_op ||
 362 +                           (!inode->i_op->lookup && !inode->i_op->lookup_it))
 363                                 break;
 364                 }
 365                 goto return_base;
 366 @@ -645,6 +698,34 @@
 367                  * Check the cached dentry for staleness.
 368                  */
 369                 dentry = nd->dentry;
 370 +               if (dentry && dentry->d_op && dentry->d_op->d_revalidate_it) {
 371 +                       err = -ESTALE;
 372 +                       if (!dentry->d_op->d_revalidate_it(dentry, 0, it)) {
 373 +                               struct dentry *new;
 374 +                               err = permission(dentry->d_parent->d_inode,
 375 +                                                MAY_EXEC);
 376 +                               if (err)
 377 +                                       break;
 378 +                               new = real_lookup(dentry->d_parent,
 379 +                                                 &dentry->d_name, 0, it);
 380 +                               if (IS_ERR(new)) {
 381 +                                       err = PTR_ERR(new);
 382 +                                       break;
 383 +                               }
 384 +                               d_invalidate(dentry);
 385 +                               dput(dentry);
 386 +                               nd->dentry = new;
 387 +                       }
 388 +                       if (!nd->dentry->d_inode)
 389 +                               goto no_inode;
 390 +                       if (lookup_flags & LOOKUP_DIRECTORY) {
 391 +                               err = -ENOTDIR;
 392 +                               if (!nd->dentry->d_inode->i_op ||
 393 +                                   (!nd->dentry->d_inode->i_op->lookup &&
 394 +                                    !nd->dentry->d_inode->i_op->lookup_it))
 395 +                                       break;
 396 +                       }
 397 +               } else
 398                 if (dentry && dentry->d_op && dentry->d_op->d_revalidate) {
 399                         err = -ESTALE;
 400                         if (!dentry->d_op->d_revalidate(dentry, 0)) {
 401 @@ -658,15 +732,28 @@
 402                 dput(dentry);
 403                 break;
 404         }
 405 +       if (err)
 406 +               intent_release(it);
 407         path_release(nd);
 408  return_err:
 409         return err;
 410  }
 411
 412 +int link_path_walk(const char * name, struct nameidata *nd)
 413 +{
 414 +       return link_path_walk_it(name, nd, NULL);
 415 +}
 416 +
 417 +int path_walk_it(const char * name, struct nameidata *nd, struct lookup_intent *it)
 418 +{
 419 +       current->total_link_count = 0;
 420 +       return link_path_walk_it(name, nd, it);
 421 +}
 422 +
 423  int path_walk(const char * name, struct nameidata *nd)
 424  {
 425         current->total_link_count = 0;
 426 -       return link_path_walk(name, nd);
 427 +       return link_path_walk_it(name, nd, NULL);
 428  }
 429
 430  /* SMP-safe */
 431 @@ -751,6 +838,17 @@
 432  }
 433
 434  /* SMP-safe */
 435 +int path_lookup_it(const char *path, unsigned flags, struct nameidata *nd,
 436 +                  struct lookup_intent *it)
 437 +{
 438 +       int error = 0;
 439 +       if (path_init(path, flags, nd))
 440 +               error = path_walk_it(path, nd, it);
 441 +       return error;
 442 +}
 443 +
 444 +
 445 +/* SMP-safe */
 446  int path_lookup(const char *path, unsigned flags, struct nameidata *nd)
 447  {
 448         int error = 0;
 449 @@ -765,6 +863,7 @@
 450  {
 451         nd->last_type = LAST_ROOT; /* if there are only slashes... */
 452         nd->flags = flags;
 453 +       nd->intent = NULL;
 454         if (*name=='/')
 455                 return walk_init_root(name,nd);
 456         read_lock(&current->fs->lock);
 457 @@ -779,7 +878,8 @@
 458   * needs parent already locked. Doesn't follow mounts.
 459   * SMP-safe.
 460   */
 461 -struct dentry * lookup_hash(struct qstr *name, struct dentry * base)
 462 +struct dentry * lookup_hash_it(struct qstr *name, struct dentry * base,
 463 +                              struct lookup_intent *it)
 464  {
 465         struct dentry * dentry;
 466         struct inode *inode;
 467 @@ -802,13 +902,16 @@
 468                         goto out;
 469         }
 470
 471 -       dentry = cached_lookup(base, name, 0);
 472 +       dentry = cached_lookup(base, name, 0, it);
 473         if (!dentry) {
 474                 struct dentry *new = d_alloc(base, name);
 475                 dentry = ERR_PTR(-ENOMEM);
 476                 if (!new)
 477                         goto out;
 478                 lock_kernel();
 479 +               if (inode->i_op->lookup_it)
 480 +                       dentry = inode->i_op->lookup_it(inode, new, it, 0);
 481 +               else
 482                 dentry = inode->i_op->lookup(inode, new);
 483                 unlock_kernel();
 484                 if (!dentry)
 485 @@ -820,6 +923,12 @@
 486         return dentry;
 487  }
 488
 489 +struct dentry * lookup_hash(struct qstr *name, struct dentry * base)
 490 +{
 491 +       return lookup_hash_it(name, base, NULL);
 492 +}
 493 +
 494 +
 495  /* SMP-safe */
 496  struct dentry * lookup_one_len(const char * name, struct dentry * base, int len)
 497  {
 498 @@ -841,7 +950,7 @@
 499         }
 500         this.hash = end_name_hash(hash);
 501
 502 -       return lookup_hash(&this, base);
 503 +       return lookup_hash_it(&this, base, NULL);
 504  access:
 505         return ERR_PTR(-EACCES);
 506  }
 507 @@ -872,6 +981,23 @@
 508         return err;
 509  }
 510
 511 +int __user_walk_it(const char *name, unsigned flags, struct nameidata *nd,
 512 +                  struct lookup_intent *it)
 513 +{
 514 +       char *tmp;
 515 +       int err;
 516 +
 517 +       tmp = getname(name);
 518 +       err = PTR_ERR(tmp);
 519 +       if (!IS_ERR(tmp)) {
 520 +               err = 0;
 521 +               if (path_init(tmp, flags, nd))
 522 +                       err = path_walk_it(tmp, nd, it);
 523 +               putname(tmp);
 524 +       }
 525 +       return err;
 526 +}
 527 +
 528  /*
 529   * It's inline, so penalty for filesystems that don't use sticky bit is
 530   * minimal.
 531 @@ -969,7 +1095,8 @@
 532         return retval;
 533  }
 534
 535 -int vfs_create(struct inode *dir, struct dentry *dentry, int mode)
 536 +static int vfs_create_it(struct inode *dir, struct dentry *dentry, int mode,
 537 +                        struct lookup_intent *it)
 538  {
 539         int error;
 540
 541 @@ -982,12 +1109,15 @@
 542                 goto exit_lock;
 543
 544         error = -EACCES;        /* shouldn't it be ENOSYS? */
 545 -       if (!dir->i_op || !dir->i_op->create)
 546 +       if (!dir->i_op || (!dir->i_op->create && !dir->i_op->create_it))
 547                 goto exit_lock;
 548
 549         DQUOT_INIT(dir);
 550         lock_kernel();
 551 -       error = dir->i_op->create(dir, dentry, mode);
 552 +       if (dir->i_op->create_it)
 553 +               error = dir->i_op->create_it(dir, dentry, mode, it);
 554 +       else
 555 +               error = dir->i_op->create(dir, dentry, mode);
 556         unlock_kernel();
 557  exit_lock:
 558         up(&dir->i_zombie);
 559 @@ -996,6 +1126,11 @@
 560         return error;
 561  }
 562
 563 +int vfs_create(struct inode *dir, struct dentry *dentry, int mode)
 564 +{
 565 +       return vfs_create_it(dir, dentry, mode, NULL);
 566 +}
 567 +
 568  /*
 569   *     open_namei()
 570   *
 571 @@ -1010,7 +1145,8 @@
 572   * for symlinks (where the permissions are checked later).
 573   * SMP-safe
 574   */
 575 -int open_namei(const char * pathname, int flag, int mode, struct nameidata *nd)
 576 +int open_namei_it(const char *pathname, int flag, int mode,
 577 +                 struct nameidata *nd, struct lookup_intent *it)
 578  {
 579         int acc_mode, error = 0;
 580         struct inode *inode;
 581 @@ -1020,11 +1156,14 @@
 582
 583         acc_mode = ACC_MODE(flag);
 584
 585 +       if (it)
 586 +               it->it_flags = flag;
 587 +
 588         /*
 589          * The simplest case - just a plain lookup.
 590          */
 591         if (!(flag & O_CREAT)) {
 592 -               error = path_lookup(pathname, lookup_flags(flag), nd);
 593 +               error = path_lookup_it(pathname, lookup_flags(flag), nd, it);
 594                 if (error)
 595                         return error;
 596                 dentry = nd->dentry;
 597 @@ -1034,6 +1173,10 @@
 598         /*
 599          * Create - we need to know the parent.
 600          */
 601 +       if (it) {
 602 +               it->it_create_mode = mode;
 603 +               it->it_op |= IT_CREAT;
 604 +       }
 605         error = path_lookup(pathname, LOOKUP_PARENT, nd);
 606         if (error)
 607                 return error;
 608 @@ -1049,7 +1192,7 @@
 609
 610         dir = nd->dentry;
 611         down(&dir->d_inode->i_sem);
 612 -       dentry = lookup_hash(&nd->last, nd->dentry);
 613 +       dentry = lookup_hash_it(&nd->last, nd->dentry, it);
 614
 615  do_last:
 616         error = PTR_ERR(dentry);
 617 @@ -1058,10 +1201,11 @@
 618                 goto exit;
 619         }
 620
 621 +       it->it_create_mode = mode;
 622         /* Negative dentry, just create the file */
 623         if (!dentry->d_inode) {
 624 -               error = vfs_create(dir->d_inode, dentry,
 625 -                                  mode & ~current->fs->umask);
 626 +               error = vfs_create_it(dir->d_inode, dentry,
 627 +                                  mode & ~current->fs->umask, it);
 628                 up(&dir->d_inode->i_sem);
 629                 dput(nd->dentry);
 630                 nd->dentry = dentry;
 631 @@ -1086,7 +1230,7 @@
 632                 error = -ELOOP;
 633                 if (flag & O_NOFOLLOW)
 634                         goto exit_dput;
 635 -               while (__follow_down(&nd->mnt,&dentry) && d_mountpoint(dentry));
 636 +               while (__follow_down(&nd->mnt,&dentry,it) && d_mountpoint(dentry));
 637         }
 638         error = -ENOENT;
 639         if (!dentry->d_inode)
 640 @@ -1165,7 +1309,7 @@
 641                 if (!error) {
 642                         DQUOT_INIT(inode);
 643
 644 -                       error = do_truncate(dentry, 0);
 645 +                       error = do_truncate(dentry, 0, 1);
 646                 }
 647                 put_write_access(inode);
 648                 if (error)
 649 @@ -1177,8 +1321,10 @@
 650         return 0;
 651
 652  exit_dput:
 653 +       intent_release(it);
 654         dput(dentry);
 655  exit:
 656 +       intent_release(it);
 657         path_release(nd);
 658         return error;
 659
 660 @@ -1197,7 +1343,16 @@
 661          * are done. Procfs-like symlinks just set LAST_BIND.
 662          */
 663         UPDATE_ATIME(dentry->d_inode);
 664 +       nd->intent = it;
 665         error = dentry->d_inode->i_op->follow_link(dentry, nd);
 666 +       if (error) {
 667 +               intent_release(it);
 668 +       } else if (it != NULL && !(it->d.lustre.it_int_flags & IT_FL_FOLLOWED)) {
 669 +               /* vfs_follow_link was never called */
 670 +               intent_release(it);
 671 +               path_release(nd);
 672 +               error = -ENOLINK;
 673 +       }
 674         dput(dentry);
 675         if (error)
 676                 return error;
 677 @@ -1219,13 +1374,20 @@
 678         }
 679         dir = nd->dentry;
 680         down(&dir->d_inode->i_sem);
 681 -       dentry = lookup_hash(&nd->last, nd->dentry);
 682 +       dentry = lookup_hash_it(&nd->last, nd->dentry, it);
 683         putname(nd->last.name);
 684         goto do_last;
 685  }
 686
 687 +int open_namei(const char *pathname, int flag, int mode, struct nameidata *nd)
 688 +{
 689 +       return open_namei_it(pathname, flag, mode, nd, NULL);
 690 +}
 691 +
 692 +
 693  /* SMP-safe */
 694 -static struct dentry *lookup_create(struct nameidata *nd, int is_dir)
 695 +static struct dentry *lookup_create(struct nameidata *nd, int is_dir,
 696 +                                   struct lookup_intent *it)
 697  {
 698         struct dentry *dentry;
 699
 700 @@ -1233,7 +1395,7 @@
 701         dentry = ERR_PTR(-EEXIST);
 702         if (nd->last_type != LAST_NORM)
 703                 goto fail;
 704 -       dentry = lookup_hash(&nd->last, nd->dentry);
 705 +       dentry = lookup_hash_it(&nd->last, nd->dentry, it);
 706         if (IS_ERR(dentry))
 707                 goto fail;
 708         if (!is_dir && nd->last.name[nd->last.len] && !dentry->d_inode)
 709 @@ -1289,7 +1451,20 @@
 710         error = path_lookup(tmp, LOOKUP_PARENT, &nd);
 711         if (error)
 712                 goto out;
 713 -       dentry = lookup_create(&nd, 0);
 714 +
 715 +       if (nd.last_type != LAST_NORM) {
 716 +               error = -EEXIST;
 717 +               goto out2;
 718 +       }
 719 +       if (nd.dentry->d_inode->i_op->mknod_raw) {
 720 +               struct inode_operations *op = nd.dentry->d_inode->i_op;
 721 +               error = op->mknod_raw(&nd, mode, dev);
 722 +               /* the file system wants to use normal vfs path now */
 723 +               if (error != -EOPNOTSUPP)
 724 +                       goto out2;
 725 +       }
 726 +
 727 +       dentry = lookup_create(&nd, 0, NULL);
 728         error = PTR_ERR(dentry);
 729
 730         mode &= ~current->fs->umask;
 731 @@ -1310,6 +1485,7 @@
 732                 dput(dentry);
 733         }
 734         up(&nd.dentry->d_inode->i_sem);
 735 +out2:
 736         path_release(&nd);
 737  out:
 738         putname(tmp);
 739 @@ -1357,7 +1533,18 @@
 740                 error = path_lookup(tmp, LOOKUP_PARENT, &nd);
 741                 if (error)
 742                         goto out;
 743 -               dentry = lookup_create(&nd, 1);
 744 +               if (nd.last_type != LAST_NORM) {
 745 +                       error = -EEXIST;
 746 +                       goto out2;
 747 +               }
 748 +               if (nd.dentry->d_inode->i_op->mkdir_raw) {
 749 +                       struct inode_operations *op = nd.dentry->d_inode->i_op;
 750 +                       error = op->mkdir_raw(&nd, mode);
 751 +                       /* the file system wants to use normal vfs path now */
 752 +                       if (error != -EOPNOTSUPP)
 753 +                               goto out2;
 754 +               }
 755 +               dentry = lookup_create(&nd, 1, NULL);
 756                 error = PTR_ERR(dentry);
 757                 if (!IS_ERR(dentry)) {
 758                         error = vfs_mkdir(nd.dentry->d_inode, dentry,
 759 @@ -1365,6 +1552,7 @@
 760                         dput(dentry);
 761                 }
 762                 up(&nd.dentry->d_inode->i_sem);
 763 +out2:
 764                 path_release(&nd);
 765  out:
 766                 putname(tmp);
 767 @@ -1465,8 +1653,16 @@
 768                         error = -EBUSY;
 769                         goto exit1;
 770         }
 771 +       if (nd.dentry->d_inode->i_op->rmdir_raw) {
 772 +               struct inode_operations *op = nd.dentry->d_inode->i_op;
 773 +
 774 +               error = op->rmdir_raw(&nd);
 775 +               /* the file system wants to use normal vfs path now */
 776 +               if (error != -EOPNOTSUPP)
 777 +                       goto exit1;
 778 +       }
 779         down(&nd.dentry->d_inode->i_sem);
 780 -       dentry = lookup_hash(&nd.last, nd.dentry);
 781 +       dentry = lookup_hash_it(&nd.last, nd.dentry, NULL);
 782         error = PTR_ERR(dentry);
 783         if (!IS_ERR(dentry)) {
 784                 error = vfs_rmdir(nd.dentry->d_inode, dentry);
 785 @@ -1524,8 +1720,15 @@
 786         error = -EISDIR;
 787         if (nd.last_type != LAST_NORM)
 788                 goto exit1;
 789 +       if (nd.dentry->d_inode->i_op->unlink_raw) {
 790 +               struct inode_operations *op = nd.dentry->d_inode->i_op;
 791 +               error = op->unlink_raw(&nd);
 792 +               /* the file system wants to use normal vfs path now */
 793 +               if (error != -EOPNOTSUPP)
 794 +                       goto exit1;
 795 +       }
 796         down(&nd.dentry->d_inode->i_sem);
 797 -       dentry = lookup_hash(&nd.last, nd.dentry);
 798 +       dentry = lookup_hash_it(&nd.last, nd.dentry, NULL);
 799         error = PTR_ERR(dentry);
 800         if (!IS_ERR(dentry)) {
 801                 /* Why not before? Because we want correct error value */
 802 @@ -1592,15 +1795,27 @@
 803                 error = path_lookup(to, LOOKUP_PARENT, &nd);
 804                 if (error)
 805                         goto out;
 806 -               dentry = lookup_create(&nd, 0);
 807 +               if (nd.last_type != LAST_NORM) {
 808 +                       error = -EEXIST;
 809 +                       goto out2;
 810 +               }
 811 +               if (nd.dentry->d_inode->i_op->symlink_raw) {
 812 +                       struct inode_operations *op = nd.dentry->d_inode->i_op;
 813 +                       error = op->symlink_raw(&nd, from);
 814 +                       /* the file system wants to use normal vfs path now */
 815 +                       if (error != -EOPNOTSUPP)
 816 +                               goto out2;
 817 +               }
 818 +               dentry = lookup_create(&nd, 0, NULL);
 819                 error = PTR_ERR(dentry);
 820                 if (!IS_ERR(dentry)) {
 821                         error = vfs_symlink(nd.dentry->d_inode, dentry, from);
 822                         dput(dentry);
 823                 }
 824                 up(&nd.dentry->d_inode->i_sem);
 825 +       out2:
 826                 path_release(&nd);
 827 -out:
 828 +       out:
 829                 putname(to);
 830         }
 831         putname(from);
 832 @@ -1676,7 +1891,18 @@
 833                 error = -EXDEV;
 834                 if (old_nd.mnt != nd.mnt)
 835                         goto out_release;
 836 -               new_dentry = lookup_create(&nd, 0);
 837 +               if (nd.last_type != LAST_NORM) {
 838 +                       error = -EEXIST;
 839 +                       goto out_release;
 840 +               }
 841 +               if (nd.dentry->d_inode->i_op->link_raw) {
 842 +                       struct inode_operations *op = nd.dentry->d_inode->i_op;
 843 +                       error = op->link_raw(&old_nd, &nd);
 844 +                       /* the file system wants to use normal vfs path now */
 845 +                       if (error != -EOPNOTSUPP)
 846 +                               goto out_release;
 847 +               }
 848 +               new_dentry = lookup_create(&nd, 0, NULL);
 849                 error = PTR_ERR(new_dentry);
 850                 if (!IS_ERR(new_dentry)) {
 851                         error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
 852 @@ -1720,7 +1946,7 @@
 853   *        locking].
 854   */
 855  int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
 856 -              struct inode *new_dir, struct dentry *new_dentry)
 857 +                  struct inode *new_dir, struct dentry *new_dentry)
 858  {
 859         int error;
 860         struct inode *target;
 861 @@ -1799,7 +2025,7 @@
 862  }
 863
 864  int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
 865 -              struct inode *new_dir, struct dentry *new_dentry)
 866 +                    struct inode *new_dir, struct dentry *new_dentry)
 867  {
 868         int error;
 869
 870 @@ -1887,9 +2113,18 @@
 871         if (newnd.last_type != LAST_NORM)
 872                 goto exit2;
 873
 874 +       if (old_dir->d_inode->i_op->rename_raw) {
 875 +               lock_kernel();
 876 +               error = old_dir->d_inode->i_op->rename_raw(&oldnd, &newnd);
 877 +               unlock_kernel();
 878 +               /* the file system wants to use normal vfs path now */
 879 +               if (error != -EOPNOTSUPP)
 880 +                       goto exit2;
 881 +       }
 882 +
 883         double_lock(new_dir, old_dir);
 884
 885 -       old_dentry = lookup_hash(&oldnd.last, old_dir);
 886 +       old_dentry = lookup_hash_it(&oldnd.last, old_dir, NULL);
 887         error = PTR_ERR(old_dentry);
 888         if (IS_ERR(old_dentry))
 889                 goto exit3;
 890 @@ -1905,16 +2140,16 @@
 891                 if (newnd.last.name[newnd.last.len])
 892                         goto exit4;
 893         }
 894 -       new_dentry = lookup_hash(&newnd.last, new_dir);
 895 +       new_dentry = lookup_hash_it(&newnd.last, new_dir, NULL);
 896         error = PTR_ERR(new_dentry);
 897         if (IS_ERR(new_dentry))
 898                 goto exit4;
 899
 900 +
 901         lock_kernel();
 902         error = vfs_rename(old_dir->d_inode, old_dentry,
 903                                    new_dir->d_inode, new_dentry);
 904         unlock_kernel();
 905 -
 906         dput(new_dentry);
 907  exit4:
 908         dput(old_dentry);
 909 @@ -1965,20 +2200,28 @@
 910  }
 911
 912  static inline int
 913 -__vfs_follow_link(struct nameidata *nd, const char *link)
 914 +__vfs_follow_link(struct nameidata *nd, const char *link,
 915 +                 struct lookup_intent *it)
 916  {
 917         int res = 0;
 918         char *name;
 919         if (IS_ERR(link))
 920                 goto fail;
 921
 922 +       if (it == NULL)
 923 +               it = nd->intent;
 924 +       else if (it != nd->intent)
 925 +               printk("it != nd->intent: tell phil@clusterfs.com\n");
 926 +       if (it != NULL)
 927 +               it->d.lustre.it_int_flags |= IT_FL_FOLLOWED;
 928 +
 929         if (*link == '/') {
 930                 path_release(nd);
 931                 if (!walk_init_root(link, nd))
 932                         /* weird __emul_prefix() stuff did it */
 933                         goto out;
 934         }
 935 -       res = link_path_walk(link, nd);
 936 +       res = link_path_walk_it(link, nd, it);
 937  out:
 938         if (current->link_count || res || nd->last_type!=LAST_NORM)
 939                 return res;
 940 @@ -2002,7 +2245,13 @@
 941
 942  int vfs_follow_link(struct nameidata *nd, const char *link)
 943  {
 944 -       return __vfs_follow_link(nd, link);
 945 +       return __vfs_follow_link(nd, link, NULL);
 946 +}
 947 +
 948 +int vfs_follow_link_it(struct nameidata *nd, const char *link,
 949 +                      struct lookup_intent *it)
 950 +{
 951 +       return __vfs_follow_link(nd, link, it);
 952  }
 953
 954  /* get the link contents into pagecache */
 955 @@ -2044,7 +2293,7 @@
 956  {
 957         struct page *page = NULL;
 958         char *s = page_getlink(dentry, &page);
 959 -       int res = __vfs_follow_link(nd, s);
 960 +       int res = __vfs_follow_link(nd, s, NULL);
 961         if (page) {
 962                 kunmap(page);
 963                 page_cache_release(page);
 964 Index: linux-2.4.20/fs/namespace.c
 965 ===================================================================
 966 --- linux-2.4.20.orig/fs/namespace.c    Wed Mar 17 13:57:05 2004
 967 +++ linux-2.4.20/fs/namespace.c Wed Mar 17 13:57:11 2004
 968 @@ -99,6 +99,7 @@
 969  {
 970         old_nd->dentry = mnt->mnt_mountpoint;
 971         old_nd->mnt = mnt->mnt_parent;
 972 +       UNPIN(old_nd->dentry, old_nd->mnt, 1);
 973         mnt->mnt_parent = mnt;
 974         mnt->mnt_mountpoint = mnt->mnt_root;
 975         list_del_init(&mnt->mnt_child);
 976 @@ -110,6 +111,7 @@
 977  {
 978         mnt->mnt_parent = mntget(nd->mnt);
 979         mnt->mnt_mountpoint = dget(nd->dentry);
 980 +       PIN(nd->dentry, nd->mnt, 1);
 981         list_add(&mnt->mnt_hash, mount_hashtable+hash(nd->mnt, nd->dentry));
 982         list_add(&mnt->mnt_child, &nd->mnt->mnt_mounts);
 983         nd->dentry->d_mounted++;
 984 @@ -485,14 +487,17 @@
 985  {
 986         struct nameidata old_nd;
 987         struct vfsmount *mnt = NULL;
 988 +       struct lookup_intent it = { .it_op = IT_GETATTR };
 989         int err = mount_is_safe(nd);
 990         if (err)
 991                 return err;
 992         if (!old_name || !*old_name)
 993                 return -EINVAL;
 994 -       err = path_lookup(old_name, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &old_nd);
 995 -       if (err)
 996 +       err = path_lookup_it(old_name, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &old_nd, &it);
 997 +       if (err) {
 998 +               intent_release(&it);
 999                 return err;
1000 +       }
1001
1002         down_write(&current->namespace->sem);
1003         err = -EINVAL;
1004 @@ -515,6 +520,7 @@
1005         }
1006
1007         up_write(&current->namespace->sem);
1008 +       intent_release(&it);
1009         path_release(&old_nd);
1010         return err;
1011  }
1012 @@ -698,6 +704,7 @@
1013                   unsigned long flags, void *data_page)
1014  {
1015         struct nameidata nd;
1016 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1017         int retval = 0;
1018         int mnt_flags = 0;
1019
1020 @@ -722,10 +729,11 @@
1021         flags &= ~(MS_NOSUID|MS_NOEXEC|MS_NODEV);
1022
1023         /* ... and get the mountpoint */
1024 -       retval = path_lookup(dir_name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd);
1025 -       if (retval)
1026 +       retval = path_lookup_it(dir_name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd, &it);
1027 +       if (retval) {
1028 +               intent_release(&it);
1029                 return retval;
1030 -
1031 +       }
1032         if (flags & MS_REMOUNT)
1033                 retval = do_remount(&nd, flags & ~MS_REMOUNT, mnt_flags,
1034                                     data_page);
1035 @@ -736,6 +744,8 @@
1036         else
1037                 retval = do_add_mount(&nd, type_page, flags, mnt_flags,
1038                                       dev_name, data_page);
1039 +
1040 +       intent_release(&it);
1041         path_release(&nd);
1042         return retval;
1043  }
1044 @@ -901,6 +911,8 @@
1045  {
1046         struct vfsmount *tmp;
1047         struct nameidata new_nd, old_nd, parent_nd, root_parent, user_nd;
1048 +       struct lookup_intent new_it = { .it_op = IT_GETATTR };
1049 +       struct lookup_intent old_it = { .it_op = IT_GETATTR };
1050         int error;
1051
1052         if (!capable(CAP_SYS_ADMIN))
1053 @@ -908,14 +920,14 @@
1054
1055         lock_kernel();
1056
1057 -       error = __user_walk(new_root, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &new_nd);
1058 +       error = __user_walk_it(new_root, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &new_nd, &new_it);
1059         if (error)
1060                 goto out0;
1061         error = -EINVAL;
1062         if (!check_mnt(new_nd.mnt))
1063                 goto out1;
1064
1065 -       error = __user_walk(put_old, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &old_nd);
1066 +       error = __user_walk_it(put_old, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &old_nd, &old_it);
1067         if (error)
1068                 goto out1;
1069
1070 @@ -970,8 +982,10 @@
1071         up(&old_nd.dentry->d_inode->i_zombie);
1072         up_write(&current->namespace->sem);
1073         path_release(&user_nd);
1074 +       intent_release(&old_it);
1075         path_release(&old_nd);
1076  out1:
1077 +       intent_release(&new_it);
1078         path_release(&new_nd);
1079  out0:
1080         unlock_kernel();
1081 Index: linux-2.4.20/fs/open.c
1082 ===================================================================
1083 --- linux-2.4.20.orig/fs/open.c Wed Mar 17 13:57:03 2004
1084 +++ linux-2.4.20/fs/open.c      Wed Mar 17 13:57:11 2004
1085 @@ -19,6 +19,8 @@
1086  #include <asm/uaccess.h>
1087
1088  #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
1089 +extern int path_walk_it(const char *name, struct nameidata *nd,
1090 +                       struct lookup_intent *it);
1091
1092  int vfs_statfs(struct super_block *sb, struct statfs *buf)
1093  {
1094 @@ -95,9 +97,10 @@
1095         write_unlock(&files->file_lock);
1096  }
1097
1098 -int do_truncate(struct dentry *dentry, loff_t length)
1099 +int do_truncate(struct dentry *dentry, loff_t length, int called_from_open)
1100  {
1101         struct inode *inode = dentry->d_inode;
1102 +       struct inode_operations *op = dentry->d_inode->i_op;
1103         int error;
1104         struct iattr newattrs;
1105
1106 @@ -108,7 +111,13 @@
1107         down(&inode->i_sem);
1108         newattrs.ia_size = length;
1109         newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
1110 -       error = notify_change(dentry, &newattrs);
1111 +       if (called_from_open)
1112 +               newattrs.ia_valid |= ATTR_FROM_OPEN;
1113 +       if (op->setattr_raw) {
1114 +               newattrs.ia_valid |= ATTR_RAW;
1115 +               error = op->setattr_raw(inode, &newattrs);
1116 +       } else
1117 +               error = notify_change(dentry, &newattrs);
1118         up(&inode->i_sem);
1119         return error;
1120  }
1121 @@ -118,12 +127,13 @@
1122         struct nameidata nd;
1123         struct inode * inode;
1124         int error;
1125 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1126
1127         error = -EINVAL;
1128         if (length < 0) /* sorry, but loff_t says... */
1129                 goto out;
1130
1131 -       error = user_path_walk(path, &nd);
1132 +       error = user_path_walk_it(path, &nd, &it);
1133         if (error)
1134                 goto out;
1135         inode = nd.dentry->d_inode;
1136 @@ -163,11 +173,13 @@
1137         error = locks_verify_truncate(inode, NULL, length);
1138         if (!error) {
1139                 DQUOT_INIT(inode);
1140 -               error = do_truncate(nd.dentry, length);
1141 +               intent_release(&it);
1142 +               error = do_truncate(nd.dentry, length, 0);
1143         }
1144         put_write_access(inode);
1145
1146  dput_and_out:
1147 +       intent_release(&it);
1148         path_release(&nd);
1149  out:
1150         return error;
1151 @@ -215,7 +227,7 @@
1152
1153         error = locks_verify_truncate(inode, file, length);
1154         if (!error)
1155 -               error = do_truncate(dentry, length);
1156 +               error = do_truncate(dentry, length, 0);
1157  out_putf:
1158         fput(file);
1159  out:
1160 @@ -260,11 +272,13 @@
1161         struct inode * inode;
1162         struct iattr newattrs;
1163
1164 -       error = user_path_walk(filename, &nd);
1165 +       error = user_path_walk_it(filename, &nd, NULL);
1166         if (error)
1167                 goto out;
1168         inode = nd.dentry->d_inode;
1169
1170 +       /* this is safe without a Lustre lock because it only depends
1171 +          on the super block */
1172         error = -EROFS;
1173         if (IS_RDONLY(inode))
1174                 goto dput_and_out;
1175 @@ -279,11 +293,25 @@
1176                         goto dput_and_out;
1177
1178                 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
1179 -       } else {
1180 +       }
1181 +
1182 +       if (inode->i_op->setattr_raw) {
1183 +               struct inode_operations *op = nd.dentry->d_inode->i_op;
1184 +
1185 +               newattrs.ia_valid |= ATTR_RAW;
1186 +               error = op->setattr_raw(inode, &newattrs);
1187 +               /* the file system wants to use normal vfs path now */
1188 +               if (error != -EOPNOTSUPP)
1189 +                       goto dput_and_out;
1190 +       }
1191 +
1192 +       error = -EPERM;
1193 +       if (!times) {
1194                 if (current->fsuid != inode->i_uid &&
1195                     (error = permission(inode,MAY_WRITE)) != 0)
1196                         goto dput_and_out;
1197         }
1198 +
1199         error = notify_change(nd.dentry, &newattrs);
1200  dput_and_out:
1201         path_release(&nd);
1202 @@ -304,12 +332,14 @@
1203         struct inode * inode;
1204         struct iattr newattrs;
1205
1206 -       error = user_path_walk(filename, &nd);
1207 +       error = user_path_walk_it(filename, &nd, NULL);
1208
1209         if (error)
1210                 goto out;
1211         inode = nd.dentry->d_inode;
1212
1213 +       /* this is safe without a Lustre lock because it only depends
1214 +          on the super block */
1215         error = -EROFS;
1216         if (IS_RDONLY(inode))
1217                 goto dput_and_out;
1218 @@ -324,7 +354,20 @@
1219                 newattrs.ia_atime = times[0].tv_sec;
1220                 newattrs.ia_mtime = times[1].tv_sec;
1221                 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
1222 -       } else {
1223 +       }
1224 +
1225 +       if (inode->i_op->setattr_raw) {
1226 +               struct inode_operations *op = nd.dentry->d_inode->i_op;
1227 +
1228 +               newattrs.ia_valid |= ATTR_RAW;
1229 +               error = op->setattr_raw(inode, &newattrs);
1230 +               /* the file system wants to use normal vfs path now */
1231 +               if (error != -EOPNOTSUPP)
1232 +                       goto dput_and_out;
1233 +       }
1234 +
1235 +       error = -EPERM;
1236 +       if (!utimes) {
1237                 if (current->fsuid != inode->i_uid &&
1238                     (error = permission(inode,MAY_WRITE)) != 0)
1239                         goto dput_and_out;
1240 @@ -347,6 +390,7 @@
1241         int old_fsuid, old_fsgid;
1242         kernel_cap_t old_cap;
1243         int res;
1244 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1245
1246         if (mode & ~S_IRWXO)    /* where's F_OK, X_OK, W_OK, R_OK? */
1247                 return -EINVAL;
1248 @@ -364,13 +408,14 @@
1249         else
1250                 current->cap_effective = current->cap_permitted;
1251
1252 -       res = user_path_walk(filename, &nd);
1253 +       res = user_path_walk_it(filename, &nd, &it);
1254         if (!res) {
1255                 res = permission(nd.dentry->d_inode, mode);
1256                 /* SuS v2 requires we report a read only fs too */
1257                 if(!res && (mode & S_IWOTH) && IS_RDONLY(nd.dentry->d_inode)
1258                    && !special_file(nd.dentry->d_inode->i_mode))
1259                         res = -EROFS;
1260 +               intent_release(&it);
1261                 path_release(&nd);
1262         }
1263
1264 @@ -385,8 +430,9 @@
1265  {
1266         int error;
1267         struct nameidata nd;
1268 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1269
1270 -       error = __user_walk(filename,LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY,&nd);
1271 +       error = __user_walk_it(filename,LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY,&nd, &it);
1272         if (error)
1273                 goto out;
1274
1275 @@ -397,6 +443,7 @@
1276         set_fs_pwd(current->fs, nd.mnt, nd.dentry);
1277
1278  dput_and_out:
1279 +       intent_release(&it);
1280         path_release(&nd);
1281  out:
1282         return error;
1283 @@ -436,9 +483,10 @@
1284  {
1285         int error;
1286         struct nameidata nd;
1287 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1288
1289 -       error = __user_walk(filename, LOOKUP_POSITIVE | LOOKUP_FOLLOW |
1290 -                     LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd);
1291 +       error = __user_walk_it(filename, LOOKUP_POSITIVE | LOOKUP_FOLLOW |
1292 +                              LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd, &it);
1293         if (error)
1294                 goto out;
1295
1296 @@ -454,39 +502,56 @@
1297         set_fs_altroot();
1298         error = 0;
1299  dput_and_out:
1300 +       intent_release(&it);
1301         path_release(&nd);
1302  out:
1303         return error;
1304  }
1305
1306 -asmlinkage long sys_fchmod(unsigned int fd, mode_t mode)
1307 +int chmod_common(struct dentry *dentry, mode_t mode)
1308  {
1309 -       struct inode * inode;
1310 -       struct dentry * dentry;
1311 -       struct file * file;
1312 -       int err = -EBADF;
1313 +       struct inode *inode = dentry->d_inode;
1314         struct iattr newattrs;
1315 +       int err = -EROFS;
1316
1317 -       file = fget(fd);
1318 -       if (!file)
1319 +       if (IS_RDONLY(inode))
1320                 goto out;
1321
1322 -       dentry = file->f_dentry;
1323 -       inode = dentry->d_inode;
1324 +       if (inode->i_op->setattr_raw) {
1325 +               newattrs.ia_mode = mode;
1326 +               newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
1327 +               newattrs.ia_valid |= ATTR_RAW;
1328 +               err = inode->i_op->setattr_raw(inode, &newattrs);
1329 +               /* the file system wants to use normal vfs path now */
1330 +               if (err != -EOPNOTSUPP)
1331 +                       goto out;
1332 +       }
1333
1334 -       err = -EROFS;
1335 -       if (IS_RDONLY(inode))
1336 -               goto out_putf;
1337         err = -EPERM;
1338         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1339 -               goto out_putf;
1340 +               goto out;
1341 +
1342         if (mode == (mode_t) -1)
1343                 mode = inode->i_mode;
1344         newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
1345         newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
1346         err = notify_change(dentry, &newattrs);
1347
1348 -out_putf:
1349 +out:
1350 +       return err;
1351 +}
1352 +
1353 +asmlinkage long sys_fchmod(unsigned int fd, mode_t mode)
1354 +{
1355 +       struct file * file;
1356 +       int err = -EBADF;
1357 +
1358 +       file = fget(fd);
1359 +       if (!file)
1360 +               goto out;
1361 +
1362 +       err = chmod_common(file->f_dentry, mode);
1363 +
1364         fput(file);
1365  out:
1366         return err;
1367 @@ -495,30 +560,14 @@
1368  asmlinkage long sys_chmod(const char * filename, mode_t mode)
1369  {
1370         struct nameidata nd;
1371 -       struct inode * inode;
1372         int error;
1373 -       struct iattr newattrs;
1374
1375         error = user_path_walk(filename, &nd);
1376         if (error)
1377                 goto out;
1378 -       inode = nd.dentry->d_inode;
1379 -
1380 -       error = -EROFS;
1381 -       if (IS_RDONLY(inode))
1382 -               goto dput_and_out;
1383 -
1384 -       error = -EPERM;
1385 -       if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1386 -               goto dput_and_out;
1387
1388 -       if (mode == (mode_t) -1)
1389 -               mode = inode->i_mode;
1390 -       newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
1391 -       newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
1392 -       error = notify_change(nd.dentry, &newattrs);
1393 +       error = chmod_common(nd.dentry, mode);
1394
1395 -dput_and_out:
1396         path_release(&nd);
1397  out:
1398         return error;
1399 @@ -538,6 +587,20 @@
1400         error = -EROFS;
1401         if (IS_RDONLY(inode))
1402                 goto out;
1403 +
1404 +       if (inode->i_op->setattr_raw) {
1405 +               struct inode_operations *op = dentry->d_inode->i_op;
1406 +
1407 +               newattrs.ia_uid = user;
1408 +               newattrs.ia_gid = group;
1409 +               newattrs.ia_valid = ATTR_UID | ATTR_GID | ATTR_CTIME;
1410 +               newattrs.ia_valid |= ATTR_RAW;
1411 +               error = op->setattr_raw(inode, &newattrs);
1412 +               /* the file system wants to use normal vfs path now */
1413 +               if (error != -EOPNOTSUPP)
1414 +                       return error;
1415 +       }
1416 +
1417         error = -EPERM;
1418         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1419                 goto out;
1420 @@ -642,8 +705,9 @@
1421  {
1422         int namei_flags, error;
1423         struct nameidata nd;
1424 -
1425 -       flags &= ~O_DIRECT;
1426 +       struct lookup_intent it = { .it_op = IT_OPEN };
1427 +
1428 +       //flags &= ~O_DIRECT;
1429
1430         namei_flags = flags;
1431         if ((namei_flags+1) & O_ACCMODE)
1432 @@ -651,14 +715,15 @@
1433         if (namei_flags & O_TRUNC)
1434                 namei_flags |= 2;
1435
1436 -       error = open_namei(filename, namei_flags, mode, &nd);
1437 -       if (!error)
1438 -               return dentry_open(nd.dentry, nd.mnt, flags);
1439 +       error = open_namei_it(filename, namei_flags, mode, &nd, &it);
1440 +       if (error)
1441 +               return ERR_PTR(error);
1442
1443 -       return ERR_PTR(error);
1444 +       return dentry_open_it(nd.dentry, nd.mnt, flags, &it);
1445  }
1446
1447 -struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
1448 +struct file *dentry_open_it(struct dentry *dentry, struct vfsmount *mnt,
1449 +                           int flags, struct lookup_intent *it)
1450  {
1451         struct file * f;
1452         struct inode *inode;
1453 @@ -695,12 +760,15 @@
1454         }
1455
1456         if (f->f_op && f->f_op->open) {
1457 +               f->f_it = it;
1458                 error = f->f_op->open(inode,f);
1459 +               f->f_it = NULL;
1460                 if (error)
1461                         goto cleanup_all;
1462         }
1463         f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
1464
1465 +       intent_release(it);
1466         return f;
1467
1468  cleanup_all:
1469 @@ -715,11 +783,17 @@
1470  cleanup_file:
1471         put_filp(f);
1472  cleanup_dentry:
1473 +       intent_release(it);
1474         dput(dentry);
1475         mntput(mnt);
1476         return ERR_PTR(error);
1477  }
1478
1479 +struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
1480 +{
1481 +       return dentry_open_it(dentry, mnt, flags, NULL);
1482 +}
1483 +
1484  /*
1485   * Find an empty file descriptor entry, and mark it busy.
1486   */
1487 Index: linux-2.4.20/fs/proc/base.c
1488 ===================================================================
1489 --- linux-2.4.20.orig/fs/proc/base.c    Wed Mar 17 13:57:05 2004
1490 +++ linux-2.4.20/fs/proc/base.c Wed Mar 17 13:57:11 2004
1491 @@ -494,6 +494,9 @@
1492
1493         error = inode->u.proc_i.op.proc_get_link(inode, &nd->dentry, &nd->mnt);
1494         nd->last_type = LAST_BIND;
1495 +
1496 +       if (nd->intent != NULL)
1497 +               nd->intent->d.lustre.it_int_flags |= IT_FL_FOLLOWED;
1498  out:
1499         return error;
1500  }
1501 Index: linux-2.4.20/fs/stat.c
1502 ===================================================================
1503 --- linux-2.4.20.orig/fs/stat.c Wed Mar 17 13:57:05 2004
1504 +++ linux-2.4.20/fs/stat.c      Wed Mar 17 13:58:01 2004
1505 @@ -17,10 +17,12 @@
1506   * Revalidate the inode. This is required for proper NFS attribute caching.
1507   */
1508  static __inline__ int
1509 -do_revalidate(struct dentry *dentry)
1510 +do_revalidate(struct dentry *dentry, struct lookup_intent *it)
1511  {
1512         struct inode * inode = dentry->d_inode;
1513 -       if (inode->i_op && inode->i_op->revalidate)
1514 +       if (inode->i_op && inode->i_op->revalidate_it)
1515 +               return inode->i_op->revalidate_it(dentry, it);
1516 +       else if (inode->i_op && inode->i_op->revalidate)
1517                 return inode->i_op->revalidate(dentry);
1518         return 0;
1519  }
1520 @@ -32,13 +34,13 @@
1521         return inode->i_nlink;
1522  }
1523
1524 -static int do_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1525 +static int do_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat, struct lookup_intent *it)
1526  {
1527         int res = 0;
1528         unsigned int blocks, indirect;
1529         struct inode *inode = dentry->d_inode;
1530
1531 -       res = do_revalidate(dentry);
1532 +       res = do_revalidate(dentry, it);
1533         if (res)
1534                 return res;
1535
1536 @@ -111,10 +113,12 @@
1537  {
1538         struct nameidata nd;
1539         int error;
1540 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1541
1542 -       error = user_path_walk(name, &nd);
1543 +       error = user_path_walk_it(name, &nd, &it);
1544         if (!error) {
1545 -               error = do_getattr(nd.mnt, nd.dentry, stat);
1546 +               error = do_getattr(nd.mnt, nd.dentry, stat, &it);
1547 +               intent_release(&it);
1548                 path_release(&nd);
1549         }
1550         return error;
1551 @@ -124,10 +128,12 @@
1552  {
1553         struct nameidata nd;
1554         int error;
1555 +       struct lookup_intent it = { .it_op = IT_GETATTR };
1556
1557 -       error = user_path_walk_link(name, &nd);
1558 +       error = user_path_walk_link_it(name, &nd, &it);
1559         if (!error) {
1560 -               error = do_getattr(nd.mnt, nd.dentry, stat);
1561 +               error = do_getattr(nd.mnt, nd.dentry, stat, &it);
1562 +               intent_release(&it);
1563                 path_release(&nd);
1564         }
1565         return error;
1566 @@ -139,7 +145,7 @@
1567         int error = -EBADF;
1568
1569         if (f) {
1570 -               error = do_getattr(f->f_vfsmnt, f->f_dentry, stat);
1571 +               error = do_getattr(f->f_vfsmnt, f->f_dentry, stat, NULL);
1572                 fput(f);
1573         }
1574         return error;
1575 @@ -286,7 +292,7 @@
1576
1577                 error = -EINVAL;
1578                 if (inode->i_op && inode->i_op->readlink &&
1579 -                   !(error = do_revalidate(nd.dentry))) {
1580 +                   !(error = do_revalidate(nd.dentry, NULL))) {
1581                         UPDATE_ATIME(inode);
1582                         error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
1583                 }
1584 Index: linux-2.4.20/include/linux/dcache.h
1585 ===================================================================
1586 --- linux-2.4.20.orig/include/linux/dcache.h    Wed Mar 17 13:57:04 2004
1587 +++ linux-2.4.20/include/linux/dcache.h Wed Mar 17 13:57:11 2004
1588 @@ -6,6 +6,51 @@
1589  #include <asm/atomic.h>
1590  #include <linux/mount.h>
1591  #include <linux/kernel.h>
1592 +#include <linux/string.h>
1593 +
1594 +#define IT_OPEN     0x0001
1595 +#define IT_CREAT    0x0002
1596 +#define IT_READDIR  0x0004
1597 +#define IT_GETATTR  0x0008
1598 +#define IT_LOOKUP   0x0010
1599 +#define IT_UNLINK   0x0020
1600 +#define IT_GETXATTR 0x0040
1601 +#define IT_EXEC     0x0080
1602 +#define IT_PIN      0x0100
1603 +
1604 +#define IT_FL_LOCKED   0x0001
1605 +#define IT_FL_FOLLOWED 0x0002 /* set by vfs_follow_link */
1606 +
1607 +#define INTENT_MAGIC 0x19620323
1608 +
1609 +
1610 +struct lustre_intent_data {
1611 +       int       it_disposition;
1612 +       int       it_status;
1613 +       __u64     it_lock_handle;
1614 +       void     *it_data;
1615 +       int       it_lock_mode;
1616 +       int it_int_flags;
1617 +};
1618 +struct lookup_intent {
1619 +       int     it_magic;
1620 +       void    (*it_op_release)(struct lookup_intent *);
1621 +       int     it_op;
1622 +       int     it_flags;
1623 +       int     it_create_mode;
1624 +       union {
1625 +               struct lustre_intent_data lustre;
1626 +       } d;
1627 +};
1628 +
1629 +static inline void intent_init(struct lookup_intent *it, int op, int flags)
1630 +{
1631 +       memset(it, 0, sizeof(*it));
1632 +       it->it_magic = INTENT_MAGIC;
1633 +       it->it_op = op;
1634 +       it->it_flags = flags;
1635 +}
1636 +
1637
1638  /*
1639   * linux/include/linux/dcache.h
1640 @@ -96,8 +141,22 @@
1641         int (*d_delete)(struct dentry *);
1642         void (*d_release)(struct dentry *);
1643         void (*d_iput)(struct dentry *, struct inode *);
1644 +       int (*d_revalidate_it)(struct dentry *, int, struct lookup_intent *);
1645 +       void (*d_pin)(struct dentry *, struct vfsmount * , int);
1646 +       void (*d_unpin)(struct dentry *, struct vfsmount *, int);
1647  };
1648
1649 +#define PIN(de,mnt,flag)  if (de && de->d_op && de->d_op->d_pin) \
1650 +                               de->d_op->d_pin(de, mnt, flag);
1651 +#define UNPIN(de,mnt,flag)  if (de && de->d_op && de->d_op->d_unpin) \
1652 +                               de->d_op->d_unpin(de, mnt, flag);
1653 +
1654 +
1655 +/* defined in fs/namei.c */
1656 +extern void intent_release(struct lookup_intent *it);
1657 +/* defined in fs/dcache.c */
1658 +extern void __d_rehash(struct dentry * entry, int lock);
1659 +
1660  /* the dentry parameter passed to d_hash and d_compare is the parent
1661   * directory of the entries to be compared. It is used in case these
1662   * functions need any directory specific information for determining
1663 @@ -129,6 +188,7 @@
1664                                          * s_nfsd_free_path semaphore will be down
1665                                          */
1666  #define DCACHE_REFERENCED      0x0008  /* Recently used, don't discard. */
1667 +#define DCACHE_LUSTRE_INVALID  0x0010  /* Lustre invalidated */
1668
1669  extern spinlock_t dcache_lock;
1670
1671 Index: linux-2.4.20/include/linux/fs.h
1672 ===================================================================
1673 --- linux-2.4.20.orig/include/linux/fs.h        Wed Mar 17 13:57:11 2004
1674 +++ linux-2.4.20/include/linux/fs.h     Wed Mar 17 13:57:11 2004
1675 @@ -73,6 +73,7 @@
1676
1677  #define FMODE_READ 1
1678  #define FMODE_WRITE 2
1679 +#define FMODE_EXEC 4
1680
1681  #define READ 0
1682  #define WRITE 1
1683 @@ -338,6 +339,9 @@
1684  #define ATTR_MTIME_SET 256
1685  #define ATTR_FORCE     512     /* Not a change, but a change it */
1686  #define ATTR_ATTR_FLAG 1024
1687 +#define ATTR_RAW       0x0800  /* file system, not vfs will massage attrs */
1688 +#define ATTR_FROM_OPEN 0x1000  /* called from open path, ie O_TRUNC */
1689 +#define ATTR_CTIME_SET 0x2000
1690
1691  /*
1692   * This is the Inode Attributes structure, used for notify_change().  It
1693 @@ -473,6 +477,7 @@
1694         struct pipe_inode_info  *i_pipe;
1695         struct block_device     *i_bdev;
1696         struct char_device      *i_cdev;
1697 +       void                    *i_filterdata;
1698
1699         unsigned long           i_dnotify_mask; /* Directory notify events */
1700         struct dnotify_struct   *i_dnotify; /* for directory notifications */
1701 @@ -575,6 +580,7 @@
1702
1703         /* needed for tty driver, and maybe others */
1704         void                    *private_data;
1705 +       struct lookup_intent    *f_it;
1706
1707         /* preallocated helper kiobuf to speedup O_DIRECT */
1708         struct kiobuf           *f_iobuf;
1709 @@ -702,6 +708,7 @@
1710         struct qstr last;
1711         unsigned int flags;
1712         int last_type;
1713 +       struct lookup_intent *intent;
1714  };
1715
1716  /*
1717 @@ -822,7 +829,8 @@
1718  extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
1719  extern int vfs_rmdir(struct inode *, struct dentry *);
1720  extern int vfs_unlink(struct inode *, struct dentry *);
1721 -extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1722 +int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1723 +              struct inode *new_dir, struct dentry *new_dentry);
1724
1725  /*
1726   * File types
1727 @@ -882,21 +890,32 @@
1728
1729  struct inode_operations {
1730         int (*create) (struct inode *,struct dentry *,int);
1731 +       int (*create_it) (struct inode *,struct dentry *,int, struct lookup_intent *);
1732         struct dentry * (*lookup) (struct inode *,struct dentry *);
1733 +       struct dentry * (*lookup_it) (struct inode *,struct dentry *, struct lookup_intent *, int flags);
1734         int (*link) (struct dentry *,struct inode *,struct dentry *);
1735 +       int (*link_raw) (struct nameidata *,struct nameidata *);
1736         int (*unlink) (struct inode *,struct dentry *);
1737 +       int (*unlink_raw) (struct nameidata *);
1738         int (*symlink) (struct inode *,struct dentry *,const char *);
1739 +       int (*symlink_raw) (struct nameidata *,const char *);
1740         int (*mkdir) (struct inode *,struct dentry *,int);
1741 +       int (*mkdir_raw) (struct nameidata *,int);
1742         int (*rmdir) (struct inode *,struct dentry *);
1743 +       int (*rmdir_raw) (struct nameidata *);
1744         int (*mknod) (struct inode *,struct dentry *,int,int);
1745 +       int (*mknod_raw) (struct nameidata *,int,dev_t);
1746         int (*rename) (struct inode *, struct dentry *,
1747                         struct inode *, struct dentry *);
1748 +       int (*rename_raw) (struct nameidata *, struct nameidata *);
1749         int (*readlink) (struct dentry *, char *,int);
1750         int (*follow_link) (struct dentry *, struct nameidata *);
1751         void (*truncate) (struct inode *);
1752         int (*permission) (struct inode *, int);
1753         int (*revalidate) (struct dentry *);
1754 +       int (*revalidate_it) (struct dentry *, struct lookup_intent *);
1755         int (*setattr) (struct dentry *, struct iattr *);
1756 +       int (*setattr_raw) (struct inode *, struct iattr *);
1757         int (*getattr) (struct dentry *, struct iattr *);
1758         int (*setxattr) (struct dentry *, const char *, void *, size_t, int);
1759         ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1760 @@ -1092,10 +1111,14 @@
1761
1762  asmlinkage long sys_open(const char *, int, int);
1763  asmlinkage long sys_close(unsigned int);       /* yes, it's really unsigned */
1764 -extern int do_truncate(struct dentry *, loff_t start);
1765 +extern int do_truncate(struct dentry *, loff_t start, int called_from_open);
1766
1767  extern struct file *filp_open(const char *, int, int);
1768  extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1769 +extern int open_namei_it(const char *filename, int namei_flags, int mode,
1770 +                        struct nameidata *nd, struct lookup_intent *it);
1771 +extern struct file *dentry_open_it(struct dentry *dentry, struct vfsmount *mnt,
1772 +                           int flags, struct lookup_intent *it);
1773  extern int filp_close(struct file *, fl_owner_t id);
1774  extern char * getname(const char *);
1775
1776 @@ -1386,6 +1409,7 @@
1777  extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1778
1779  extern int FASTCALL(__user_walk(const char *, unsigned, struct nameidata *));
1780 +extern int FASTCALL(__user_walk_it(const char *, unsigned, struct nameidata *, struct lookup_intent *it));
1781  extern int FASTCALL(path_init(const char *, unsigned, struct nameidata *));
1782  extern int FASTCALL(path_walk(const char *, struct nameidata *));
1783  extern int FASTCALL(path_lookup(const char *, unsigned, struct nameidata *));
1784 @@ -1397,6 +1421,8 @@
1785  extern struct dentry * lookup_hash(struct qstr *, struct dentry *);
1786  #define user_path_walk(name,nd)         __user_walk(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, nd)
1787  #define user_path_walk_link(name,nd) __user_walk(name, LOOKUP_POSITIVE, nd)
1788 +#define user_path_walk_it(name,nd,it)  __user_walk_it(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, nd, it)
1789 +#define user_path_walk_link_it(name,nd,it) __user_walk_it(name, LOOKUP_POSITIVE, nd, it)
1790
1791  extern void inode_init_once(struct inode *);
1792  extern void iput(struct inode *);
1793 @@ -1504,6 +1530,8 @@
1794
1795  extern int vfs_readlink(struct dentry *, char *, int, const char *);
1796  extern int vfs_follow_link(struct nameidata *, const char *);
1797 +extern int vfs_follow_link_it(struct nameidata *, const char *,
1798 +                             struct lookup_intent *it);
1799  extern int page_readlink(struct dentry *, char *, int);
1800  extern int page_follow_link(struct dentry *, struct nameidata *);
1801  extern struct inode_operations page_symlink_inode_operations;
1802 Index: linux-2.4.20/include/linux/fs_struct.h
1803 ===================================================================
1804 --- linux-2.4.20.orig/include/linux/fs_struct.h Wed Mar 17 13:57:02 2004
1805 +++ linux-2.4.20/include/linux/fs_struct.h      Wed Mar 17 13:57:11 2004
1806 @@ -37,10 +37,12 @@
1807         write_lock(&fs->lock);
1808         old_root = fs->root;
1809         old_rootmnt = fs->rootmnt;
1810 +       PIN(dentry, mnt, 1);
1811         fs->rootmnt = mntget(mnt);
1812         fs->root = dget(dentry);
1813         write_unlock(&fs->lock);
1814         if (old_root) {
1815 +               UNPIN(old_root, old_rootmnt, 1);
1816                 dput(old_root);
1817                 mntput(old_rootmnt);
1818         }
1819 @@ -60,10 +62,12 @@
1820         write_lock(&fs->lock);
1821         old_pwd = fs->pwd;
1822         old_pwdmnt = fs->pwdmnt;
1823 +       PIN(dentry, mnt, 0);
1824         fs->pwdmnt = mntget(mnt);
1825         fs->pwd = dget(dentry);
1826         write_unlock(&fs->lock);
1827         if (old_pwd) {
1828 +               UNPIN(old_pwd, old_pwdmnt, 0);
1829                 dput(old_pwd);
1830                 mntput(old_pwdmnt);
1831         }
1832 Index: linux-2.4.20/kernel/ksyms.c
1833 ===================================================================
1834 --- linux-2.4.20.orig/kernel/ksyms.c    Wed Mar 17 13:57:11 2004
1835 +++ linux-2.4.20/kernel/ksyms.c Wed Mar 17 13:57:11 2004
1836 @@ -297,6 +297,7 @@
1837  EXPORT_SYMBOL(set_page_dirty);
1838  EXPORT_SYMBOL(vfs_readlink);
1839  EXPORT_SYMBOL(vfs_follow_link);
1840 +EXPORT_SYMBOL(vfs_follow_link_it);
1841  EXPORT_SYMBOL(page_readlink);
1842  EXPORT_SYMBOL(page_follow_link);
1843  EXPORT_SYMBOL(page_symlink_inode_operations);
1844 Index: linux-2.4.20/kernel/fork.c
1845 ===================================================================
1846 --- linux-2.4.20.orig/kernel/fork.c     Wed Mar 17 13:57:05 2004
1847 +++ linux-2.4.20/kernel/fork.c  Wed Mar 17 13:57:11 2004
1848 @@ -440,10 +440,13 @@
1849                 fs->umask = old->umask;
1850                 read_lock(&old->lock);
1851                 fs->rootmnt = mntget(old->rootmnt);
1852 +               PIN(old->pwd, old->pwdmnt, 0);
1853 +               PIN(old->root, old->rootmnt, 1);
1854                 fs->root = dget(old->root);
1855                 fs->pwdmnt = mntget(old->pwdmnt);
1856                 fs->pwd = dget(old->pwd);
1857                 if (old->altroot) {
1858 +                       PIN(old->altroot, old->altrootmnt, 1);
1859                         fs->altrootmnt = mntget(old->altrootmnt);
1860                         fs->altroot = dget(old->altroot);
1861                 } else {
1862 Index: linux-2.4.20/kernel/exit.c
1863 ===================================================================
1864 --- linux-2.4.20.orig/kernel/exit.c     Wed Mar 17 13:57:05 2004
1865 +++ linux-2.4.20/kernel/exit.c  Wed Mar 17 13:57:11 2004
1866 @@ -345,11 +345,14 @@
1867  {
1868         /* No need to hold fs->lock if we are killing it */
1869         if (atomic_dec_and_test(&fs->count)) {
1870 +               UNPIN(fs->pwd, fs->pwdmnt, 0);
1871 +               UNPIN(fs->root, fs->rootmnt, 1);
1872                 dput(fs->root);
1873                 mntput(fs->rootmnt);
1874                 dput(fs->pwd);
1875                 mntput(fs->pwdmnt);
1876                 if (fs->altroot) {
1877 +                       UNPIN(fs->altroot, fs->altrootmnt, 1);
1878                         dput(fs->altroot);
1879                         mntput(fs->altrootmnt);
1880                 }