lustre/smfs/dir.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2004 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_SM
  24
  25 #include <linux/module.h>
  26 #include <linux/kernel.h>
  27 #include <linux/string.h>
  28 #include <linux/slab.h>
  29 #include <linux/stat.h>
  30 #include <linux/unistd.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/obd_class.h>
  33 #include <linux/obd_support.h>
  34 #include <linux/lustre_lib.h>
  35 #include <linux/lustre_idl.h>
  36 #include <linux/lustre_fsfilt.h>
  37 #include <linux/lustre_smfs.h>
  38 #include <linux/lustre_snap.h>
  39
  40 #include "smfs_internal.h"
  41
  42 #define NAME_ALLOC_LEN(len)     ((len+16) & ~15)
  43
  44 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  45 static int smfs_create(struct inode *dir, struct dentry *dentry,
  46                        int mode)
  47 #else
  48 static int smfs_create(struct inode *dir, struct dentry *dentry,
  49                        int mode, struct nameidata *nd)
  50 #endif
  51 {
  52         struct inode  *inode = NULL;
  53         struct inode  *cache_dir = NULL;
  54         struct dentry *cache_dentry = NULL;
  55         struct dentry *cache_parent = NULL;
  56         void *handle = NULL;
  57         int rc = 0;
  58
  59         ENTRY;
  60
  61         cache_dir = I2CI(dir);
  62         if (!cache_dir)
  63                 RETURN(-ENOENT);
  64
  65         handle = smfs_trans_start(dir, FSFILT_OP_CREATE, NULL);
  66         if (IS_ERR(handle))
  67                        RETURN(-ENOSPC);
  68
  69         lock_kernel();
  70         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_CREATE, handle,
  71                   PRE_HOOK, rc, exit);
  72
  73         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
  74         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
  75
  76         if (!cache_dentry || !cache_parent)
  77                 GOTO(exit, rc = -ENOMEM);
  78
  79         pre_smfs_inode(dir, cache_dir);
  80
  81 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  82         if (cache_dir && cache_dir->i_op->create)
  83                 rc = cache_dir->i_op->create(cache_dir, cache_dentry,
  84                                              mode);
  85 #else
  86         if (cache_dir && cache_dir->i_op->create)
  87                 rc = cache_dir->i_op->create(cache_dir, cache_dentry,
  88                                              mode, nd);
  89 #endif
  90         if (rc)
  91                 GOTO(exit, rc);
  92
  93         SMFS_GET_INODE(dir->i_sb, cache_dentry->d_inode, dir, inode,
  94                        rc, exit);
  95
  96         d_instantiate(dentry, inode);
  97         post_smfs_inode(dir, cache_dir);
  98
  99         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_CREATE, handle,
 100                   POST_HOOK, rc,  exit);
 101 exit:
 102         unlock_kernel();
 103         post_smfs_dentry(cache_dentry);
 104         post_smfs_dentry(cache_parent);
 105         smfs_trans_commit(dir, handle, 0);
 106         RETURN(rc);
 107 }
 108
 109 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 110 static struct dentry *smfs_lookup(struct inode *dir, struct dentry *dentry)
 111 #else
 112 static struct dentry *smfs_lookup(struct inode *dir, struct dentry *dentry,
 113                                   struct nameidata *nd)
 114 #endif
 115 {
 116         struct inode *cache_dir;
 117         struct inode *cache_inode;
 118         struct inode *inode = NULL;
 119         struct dentry *cache_dentry = NULL;
 120         struct dentry *cache_parent = NULL;
 121         struct dentry *rc = NULL;
 122         void *handle = NULL;
 123         int rc2 = 0;
 124
 125         ENTRY;
 126
 127         if (!(cache_dir = I2CI(dir)))
 128                 RETURN(ERR_PTR(-ENOENT));
 129
 130         /* preparing artificial backing fs dentries. */
 131         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry->d_parent);
 132         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
 133
 134         if (!cache_dentry || !cache_parent)
 135                 GOTO(exit, rc = ERR_PTR(-ENOMEM));
 136
 137         if (!cache_dir && cache_dir->i_op->lookup)
 138                 GOTO(exit, rc = ERR_PTR(-ENOENT));
 139
 140         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_LOOKUP, handle,
 141                   PRE_HOOK, rc2, exit);
 142
 143         /* perform lookup in backing fs. */
 144 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 145         rc = cache_dir->i_op->lookup(cache_dir, cache_dentry);
 146 #else
 147         rc = cache_dir->i_op->lookup(cache_dir, cache_dentry, nd);
 148 #endif
 149         if (rc && IS_ERR(rc))
 150                 GOTO(exit, rc);
 151
 152         if ((cache_inode = rc ? rc->d_inode : cache_dentry->d_inode)) {
 153                 if (IS_ERR(cache_inode)) {
 154                         dentry->d_inode = cache_inode;
 155                         GOTO(exit, rc = NULL);
 156                 }
 157                 SMFS_GET_INODE(dir->i_sb, cache_inode, dir, inode, rc2, exit);
 158         }
 159
 160         d_add(dentry, inode);
 161         rc = NULL;
 162
 163         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_LOOKUP, handle, POST_HOOK, rc2,
 164                   exit);
 165 exit:
 166         if (rc2 < 0)
 167                 rc = ERR_PTR(rc2);
 168         post_smfs_dentry(cache_dentry);
 169         post_smfs_dentry(cache_parent);
 170         smfs_trans_commit(dir, handle, 0);
 171         RETURN(rc);
 172 }
 173
 174 static int smfs_link(struct dentry *old_dentry,
 175                      struct inode *dir, struct dentry *dentry)
 176 {
 177         struct inode *cache_old_inode = NULL;
 178         struct inode *cache_dir = I2CI(dir);
 179         struct inode *inode = NULL;
 180         struct dentry *cache_dentry = NULL;
 181         struct dentry *cache_old_dentry = NULL;
 182         struct dentry *cache_parent = NULL;
 183         void *handle = NULL;
 184         int rc = 0;
 185
 186         inode = old_dentry->d_inode;
 187         cache_old_inode = I2CI(inode);
 188
 189         handle = smfs_trans_start(dir, FSFILT_OP_LINK, NULL);
 190         if (IS_ERR(handle))
 191                  RETURN(-ENOSPC);
 192
 193         lock_kernel();
 194         SMFS_HOOK(dir, old_dentry, NULL, NULL, HOOK_LINK, handle,
 195                   PRE_HOOK, rc, exit);
 196
 197         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
 198         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
 199
 200         if (!cache_parent || !cache_dentry)
 201                 GOTO(exit, rc = -ENOMEM);
 202
 203         cache_old_dentry = pre_smfs_dentry(NULL, cache_old_inode,
 204                                            old_dentry);
 205         if (!cache_old_dentry)
 206                 GOTO(exit, rc = -ENOMEM);
 207
 208         pre_smfs_inode(dir, cache_dir);
 209         pre_smfs_inode(inode, cache_old_dentry->d_inode);
 210
 211         if (cache_dir->i_op->link)
 212                 rc = cache_dir->i_op->link(cache_old_dentry, cache_dir,
 213                                            cache_dentry);
 214         if (rc)
 215                 GOTO(exit, rc);
 216
 217         atomic_inc(&inode->i_count);
 218         post_smfs_inode(inode, cache_old_dentry->d_inode);
 219         d_instantiate(dentry, inode);
 220         post_smfs_inode(dir, cache_dir);
 221
 222         SMFS_HOOK(dir, old_dentry, dentry, NULL, HOOK_LINK, handle,
 223                   POST_HOOK, rc, exit);
 224 exit:
 225         unlock_kernel();
 226         post_smfs_dentry(cache_dentry);
 227         post_smfs_dentry(cache_parent);
 228         post_smfs_dentry(cache_old_dentry);
 229         smfs_trans_commit(dir, handle, 0);
 230         RETURN(rc);
 231 }
 232
 233 static int smfs_unlink(struct inode * dir,
 234                        struct dentry *dentry)
 235 {
 236         struct inode *cache_dir = I2CI(dir);
 237         struct inode *cache_inode = I2CI(dentry->d_inode);
 238         struct dentry *cache_dentry;
 239         struct dentry *cache_parent;
 240         void   *handle = NULL;
 241         int    rc = 0;
 242         int    mode = 0;
 243
 244         if (!cache_dir || !cache_inode)
 245                 RETURN(-ENOENT);
 246
 247         handle = smfs_trans_start(dir, FSFILT_OP_UNLINK, NULL);
 248         if (IS_ERR(handle))
 249                 RETURN(-ENOSPC);
 250
 251         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_UNLINK, handle, PRE_HOOK, rc,
 252                   exit);
 253
 254         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
 255         cache_dentry = pre_smfs_dentry(cache_parent, cache_inode, dentry);
 256
 257         if (!cache_parent || !cache_dentry)
 258                 GOTO(exit, rc = -ENOMEM);
 259
 260         lock_kernel();
 261         pre_smfs_inode(dir, cache_dir);
 262         pre_smfs_inode(dentry->d_inode, cache_inode);
 263         if (cache_dir->i_op->unlink)
 264                 rc = cache_dir->i_op->unlink(cache_dir, cache_dentry);
 265         post_smfs_inode(dentry->d_inode, cache_dentry->d_inode);
 266         post_smfs_inode(dir, cache_dir);
 267         unlock_kernel();
 268
 269         SMFS_HOOK(dir, dentry, &mode, NULL, HOOK_UNLINK, handle, POST_HOOK,
 270                   rc, exit);
 271 exit:
 272         post_smfs_dentry(cache_dentry);
 273         post_smfs_dentry(cache_parent);
 274         smfs_trans_commit(dir, handle, 0);
 275         RETURN(rc);
 276 }
 277
 278 static int smfs_symlink(struct inode *dir, struct dentry *dentry,
 279                         const char *symname)
 280 {
 281         struct inode *cache_dir = I2CI(dir);
 282         struct inode *inode = NULL;
 283         struct dentry *cache_dentry;
 284         struct dentry *cache_parent;
 285         void   *handle = NULL;
 286         int    rc = 0, tgt_len;
 287
 288         if (!cache_dir)
 289                 RETURN(-ENOENT);
 290
 291         handle = smfs_trans_start(dir, FSFILT_OP_SYMLINK, NULL);
 292         if (IS_ERR(handle))
 293                 RETURN(-ENOSPC);
 294
 295         lock_kernel();
 296         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_SYMLINK, handle, PRE_HOOK, rc,
 297                   exit);
 298
 299         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
 300         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
 301
 302         if (!cache_parent || !cache_dentry)
 303                 GOTO(exit, rc = -ENOMEM);
 304
 305         pre_smfs_inode(dir, cache_dir);
 306         if (cache_dir->i_op->symlink)
 307                 rc = cache_dir->i_op->symlink(cache_dir, cache_dentry, symname);
 308
 309         post_smfs_inode(dir, cache_dir);
 310
 311         SMFS_GET_INODE(dir->i_sb, cache_dentry->d_inode, dir, inode, rc, exit);
 312         if (inode)
 313                 d_instantiate(dentry, inode);
 314         else
 315                 rc = -ENOENT;
 316
 317         tgt_len = strlen(symname) + 1;
 318
 319         SMFS_HOOK(dir, dentry, (char *)symname, &tgt_len, HOOK_SYMLINK, handle,
 320                   POST_HOOK, rc, exit);
 321 exit:
 322         unlock_kernel();
 323         post_smfs_dentry(cache_dentry);
 324         post_smfs_dentry(cache_parent);
 325         smfs_trans_commit(dir, handle, 0);
 326         RETURN(rc);
 327 }
 328
 329 static int smfs_mkdir(struct inode *dir, struct dentry *dentry,
 330                       int mode)
 331 {
 332         struct inode *cache_dir = I2CI(dir);
 333         struct inode *inode = NULL;
 334         struct dentry *cache_dentry;
 335         struct dentry *cache_parent;
 336         void   *handle = NULL;
 337         int    rc = 0;
 338
 339         if (!cache_dir)
 340                 RETURN(-ENOENT);
 341
 342         handle = smfs_trans_start(dir, FSFILT_OP_MKDIR, NULL);
 343         if (IS_ERR(handle))
 344                 RETURN(-ENOSPC);
 345
 346         lock_kernel();
 347
 348         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_MKDIR, handle, PRE_HOOK, rc,
 349                   exit);
 350
 351         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
 352         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
 353
 354         if (!cache_parent || !cache_dentry)
 355                 GOTO(exit, rc = -ENOMEM);
 356
 357         pre_smfs_inode(dir, cache_dir);
 358
 359         if (cache_dir->i_op->mkdir)
 360                 rc = cache_dir->i_op->mkdir(cache_dir, cache_dentry, mode);
 361
 362         if (rc)
 363                 GOTO(exit, rc);
 364
 365         SMFS_GET_INODE(dir->i_sb, cache_dentry->d_inode, dir, inode, rc, exit);
 366         d_instantiate(dentry, inode);
 367         post_smfs_inode(dir, cache_dir);
 368
 369         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_MKDIR, handle, POST_HOOK, rc,
 370                   exit);
 371 exit:
 372         unlock_kernel();
 373         post_smfs_dentry(cache_dentry);
 374         post_smfs_dentry(cache_parent);
 375         smfs_trans_commit(dir, handle, 0);
 376         RETURN(rc);
 377 }
 378
 379 static int smfs_rmdir(struct inode *dir, struct dentry *dentry)
 380 {
 381         struct inode *cache_dir = I2CI(dir);
 382         struct inode *cache_inode = I2CI(dentry->d_inode);
 383         struct dentry *cache_dentry = NULL;
 384         struct dentry *cache_parent = NULL;
 385         void *handle = NULL;
 386         int    rc = 0, mode = S_IFDIR;
 387
 388         if (!cache_dir)
 389                 RETURN(-ENOENT);
 390
 391         handle = smfs_trans_start(dir, FSFILT_OP_RMDIR, NULL);
 392         if (IS_ERR(handle) ) {
 393                 CERROR("smfs_do_mkdir: no space for transaction\n");
 394                 RETURN(-ENOSPC);
 395         }
 396
 397         lock_kernel();
 398
 399         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_RMDIR, handle, PRE_HOOK, rc,
 400                   exit);
 401
 402         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry);
 403         cache_dentry = pre_smfs_dentry(cache_parent, cache_inode, dentry);
 404
 405         if (!cache_parent || !cache_dentry)
 406                 GOTO(exit, rc = -ENOMEM);
 407
 408         pre_smfs_inode(dir, cache_dir);
 409         pre_smfs_inode(dentry->d_inode, cache_dentry->d_inode);
 410         if (cache_dir->i_op->rmdir)
 411                 rc = cache_dir->i_op->rmdir(cache_dir, cache_dentry);
 412
 413         post_smfs_inode(dir, cache_dir);
 414         post_smfs_inode(dentry->d_inode, cache_dentry->d_inode);
 415         unlock_kernel();
 416
 417         SMFS_HOOK(dir, dentry, &mode, NULL, HOOK_RMDIR, handle, POST_HOOK,
 418                   rc, exit);
 419 exit:
 420         post_smfs_dentry(cache_dentry);
 421         post_smfs_dentry(cache_parent);
 422         smfs_trans_commit(dir, handle, 0);
 423         RETURN(rc);
 424 }
 425
 426 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 427 static int smfs_mknod(struct inode *dir, struct dentry *dentry,
 428                       int mode, int rdev)
 429 #else
 430 static int smfs_mknod(struct inode *dir, struct dentry *dentry,
 431                       int mode, dev_t rdev)
 432 #endif
 433 {
 434         struct inode *cache_dir = I2CI(dir);
 435         struct inode *inode = NULL;
 436         struct dentry *cache_dentry = NULL;
 437         struct dentry *cache_parent = NULL;
 438         void *handle = NULL;
 439         int rc = 0;
 440
 441         if (!cache_dir)
 442                 RETURN(-ENOENT);
 443
 444         handle = smfs_trans_start(dir, FSFILT_OP_MKNOD, NULL);
 445         if (IS_ERR(handle)) {
 446                 CERROR("smfs_do_mkdir: no space for transaction\n");
 447                 RETURN(-ENOSPC);
 448         }
 449
 450         lock_kernel();
 451         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_MKNOD, handle, PRE_HOOK, rc,
 452                   exit);
 453
 454         cache_parent = pre_smfs_dentry(NULL, cache_dir, dentry->d_parent);
 455         cache_dentry = pre_smfs_dentry(cache_parent, NULL, dentry);
 456         if (!cache_parent || !cache_dentry)
 457                 GOTO(exit, rc = -ENOMEM);
 458
 459         pre_smfs_inode(dir, cache_dir);
 460         pre_smfs_inode(dentry->d_inode, cache_dentry->d_inode);
 461
 462         if (!cache_dir->i_op->mknod)
 463                 RETURN(-ENOENT);
 464
 465         if ((rc = cache_dir->i_op->mknod(cache_dir, cache_dentry,
 466                                          mode, rdev)))
 467                 GOTO(exit, rc);
 468
 469         SMFS_GET_INODE(dir->i_sb, cache_dentry->d_inode, dir, inode, rc, exit);
 470
 471         d_instantiate(dentry, inode);
 472
 473         pre_smfs_inode(dir, cache_dir);
 474         pre_smfs_inode(dentry->d_inode, cache_dentry->d_inode);
 475
 476         SMFS_HOOK(dir, dentry, NULL, NULL, HOOK_MKNOD, handle, POST_HOOK, rc,
 477                   exit);
 478
 479 exit:
 480         unlock_kernel();
 481         post_smfs_dentry(cache_dentry);
 482         post_smfs_dentry(cache_parent);
 483         smfs_trans_commit(dir, handle, 0);
 484         RETURN(rc);
 485 }
 486
 487 static int smfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 488                        struct inode *new_dir,struct dentry *new_dentry)
 489 {
 490         struct inode *cache_old_dir = I2CI(old_dir);
 491         struct inode *cache_new_dir = I2CI(new_dir);
 492         struct inode *cache_old_inode = I2CI(old_dentry->d_inode);
 493
 494         struct inode *cache_new_inode = new_dentry->d_inode ?
 495             I2CI(new_dentry->d_inode) : NULL;
 496
 497         struct dentry *cache_old_dentry = NULL;
 498         struct dentry *cache_new_dentry = NULL;
 499         struct dentry *cache_new_parent = NULL;
 500         struct dentry *cache_old_parent = NULL;
 501         void *handle = NULL;
 502         int    rc = 0;
 503
 504         if (!cache_old_dir || !cache_new_dir || !cache_old_inode)
 505                 RETURN(-ENOENT);
 506
 507         handle = smfs_trans_start(old_dir, FSFILT_OP_RENAME, NULL);
 508         if (IS_ERR(handle)) {
 509                 CERROR("smfs_do_mkdir: no space for transaction\n");
 510                 RETURN(-ENOSPC);
 511         }
 512         lock_kernel();
 513
 514
 515         SMFS_HOOK(old_dir, old_dentry, new_dir, new_dentry, HOOK_RENAME,
 516                   handle, PRE_HOOK, rc, exit);
 517
 518         cache_old_parent = pre_smfs_dentry(NULL, cache_old_dir, old_dentry);
 519
 520         cache_old_dentry = pre_smfs_dentry(cache_old_parent, cache_old_inode,
 521                                            old_dentry);
 522
 523         if (!cache_old_parent || !cache_old_dentry)
 524                 GOTO(exit, rc = -ENOMEM);
 525
 526         cache_new_parent = pre_smfs_dentry(NULL, cache_new_dir, new_dentry);
 527
 528         cache_new_dentry = pre_smfs_dentry(cache_new_parent, cache_new_inode,
 529                                            new_dentry);
 530
 531         if (!cache_new_parent || !cache_new_dentry)
 532                 GOTO(exit, rc = -ENOMEM);
 533
 534         pre_smfs_inode(old_dir, cache_old_dir);
 535         pre_smfs_inode(new_dir, cache_new_dir);
 536
 537         if (cache_old_dir->i_op->rename)
 538                 rc = cache_old_dir->i_op->rename(cache_old_dir, cache_old_dentry,
 539                                                  cache_new_dir, cache_new_dentry);
 540
 541         post_smfs_inode(old_dir, cache_old_dir);
 542         post_smfs_inode(new_dir, cache_new_dir);
 543
 544         SMFS_HOOK(old_dir, old_dentry, new_dir, new_dentry, HOOK_RENAME, handle,
 545                   POST_HOOK, rc, exit);
 546
 547         if (new_dentry->d_inode)
 548                 post_smfs_inode(new_dentry->d_inode, cache_new_dentry->d_inode);
 549 exit:
 550         unlock_kernel();
 551         post_smfs_dentry(cache_old_dentry);
 552         post_smfs_dentry(cache_old_parent);
 553         post_smfs_dentry(cache_new_dentry);
 554         post_smfs_dentry(cache_new_parent);
 555         smfs_trans_commit(old_dir, handle, 0);
 556         RETURN(rc);
 557 }
 558
 559 struct inode_operations smfs_dir_iops = {
 560         create:         smfs_create,
 561         lookup:         smfs_lookup,
 562         link:           smfs_link,              /* BKL held */
 563         unlink:         smfs_unlink,            /* BKL held */
 564         symlink:        smfs_symlink,           /* BKL held */
 565         mkdir:          smfs_mkdir,             /* BKL held */
 566         rmdir:          smfs_rmdir,             /* BKL held */
 567         mknod:          smfs_mknod,             /* BKL held */
 568         rename:         smfs_rename,            /* BKL held */
 569         setxattr:       smfs_setxattr,          /* BKL held */
 570         getxattr:       smfs_getxattr,          /* BKL held */
 571         listxattr:      smfs_listxattr,         /* BKL held */
 572         removexattr:    smfs_removexattr,       /* BKL held */
 573 };
 574
 575 static ssize_t smfs_read_dir(struct file *filp, char *buf,
 576                              size_t size, loff_t *ppos)
 577 {
 578         struct dentry *dentry = filp->f_dentry;
 579         struct inode *cache_inode = NULL;
 580         struct smfs_file_info *sfi = NULL;
 581         loff_t tmp_ppos;
 582         loff_t *cache_ppos;
 583         int    rc = 0;
 584
 585         cache_inode = I2CI(dentry->d_inode);
 586
 587         if (!cache_inode)
 588                 RETURN(-EINVAL);
 589
 590         sfi = F2SMFI(filp);
 591         if (sfi->magic != SMFS_FILE_MAGIC) BUG();
 592
 593         if (ppos != &(filp->f_pos))
 594                 cache_ppos = &tmp_ppos;
 595         else
 596                 cache_ppos = &sfi->c_file->f_pos;
 597         *cache_ppos = *ppos;
 598
 599         if (cache_inode->i_fop->read)
 600                 rc = cache_inode->i_fop->read(sfi->c_file, buf, size,
 601                                               cache_ppos);
 602         *ppos = *cache_ppos;
 603         duplicate_file(filp, sfi->c_file);
 604         RETURN(rc);
 605 }
 606
 607 static int smfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 608 {
 609         struct dentry *dentry = filp->f_dentry;
 610         struct inode *cache_inode = NULL;
 611         struct smfs_file_info *sfi = NULL;
 612         int    rc = 0;
 613
 614         cache_inode = I2CI(dentry->d_inode);
 615         if (!cache_inode)
 616                 RETURN(-EINVAL);
 617
 618         sfi = F2SMFI(filp);
 619         if (sfi->magic != SMFS_FILE_MAGIC) BUG();
 620
 621         SMFS_HOOK(dentry->d_inode, filp, dirent, filldir, HOOK_READDIR, NULL,
 622                   PRE_HOOK, rc, exit);
 623
 624         if (cache_inode->i_fop->readdir)
 625                 rc = cache_inode->i_fop->readdir(sfi->c_file, dirent, filldir);
 626
 627         SMFS_HOOK(dentry->d_inode, filp, dirent, filldir, HOOK_READDIR, NULL,
 628                   POST_HOOK, rc, exit);
 629
 630         duplicate_file(filp, sfi->c_file);
 631 exit:
 632         if (rc > 0)
 633                 rc = 0;
 634         RETURN(rc);
 635 }
 636
 637 struct file_operations smfs_dir_fops = {
 638         .read           = smfs_read_dir,
 639         .readdir        = smfs_readdir,       /* BKL held */
 640         .ioctl          = smfs_ioctl,         /* BKL held */
 641         .fsync          = smfs_fsync,         /* BKL held */
 642         .open           = smfs_open,
 643         .release        = smfs_release,
 644 };