lustre/llite/super.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Lustre Light Super operations
   5  *
   6  * This code is issued under the GNU General Public License.
   7  * See the file COPYING in this distribution
   8  *
   9  * Copryright (C) 2002 Cluster File Systems, Inc.
  10  */
  11
  12 #define DEBUG_SUBSYSTEM S_LLITE
  13
  14 #include <linux/module.h>
  15 #include <linux/random.h>
  16 #include <linux/version.h>
  17 #include <linux/lustre_lite.h>
  18 #include <linux/lustre_ha.h>
  19 #include <linux/lustre_dlm.h>
  20 #include <linux/init.h>
  21 #include <linux/fs.h>
  22 #include <linux/lprocfs_status.h>
  23
  24 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  25 kmem_cache_t *ll_file_data_slab;
  26 extern struct address_space_operations ll_aops;
  27 extern struct address_space_operations ll_dir_aops;
  28 struct super_operations ll_super_operations;
  29
  30 extern int ll_recover(struct recovd_data *, int);
  31 extern int ll_commitcbd_setup(struct ll_sb_info *);
  32 extern int ll_commitcbd_cleanup(struct ll_sb_info *);
  33
  34 extern void ll_proc_namespace(struct super_block* sb, char* osc, char* mdc);
  35
  36 static char *ll_read_opt(const char *opt, char *data)
  37 {
  38         char *value;
  39         char *retval;
  40         ENTRY;
  41
  42         CDEBUG(D_SUPER, "option: %s, data %s\n", opt, data);
  43         if ( strncmp(opt, data, strlen(opt)) )
  44                 RETURN(NULL);
  45         if ( (value = strchr(data, '=')) == NULL )
  46                 RETURN(NULL);
  47
  48         value++;
  49         OBD_ALLOC(retval, strlen(value) + 1);
  50         if ( !retval ) {
  51                 CERROR("out of memory!\n");
  52                 RETURN(NULL);
  53         }
  54
  55         memcpy(retval, value, strlen(value)+1);
  56         CDEBUG(D_SUPER, "Assigned option: %s, value %s\n", opt, retval);
  57         RETURN(retval);
  58 }
  59
  60 static int ll_set_opt(const char *opt, char *data, int fl)
  61 {
  62         ENTRY;
  63
  64         CDEBUG(D_SUPER, "option: %s, data %s\n", opt, data);
  65         if ( strncmp(opt, data, strlen(opt)) )
  66                 RETURN(0);
  67         else
  68                 RETURN(fl);
  69 }
  70
  71 static void ll_options(char *options, char **ost, char **mds, int *flags)
  72 {
  73         char *this_char;
  74         ENTRY;
  75
  76         if (!options) {
  77                 EXIT;
  78                 return;
  79         }
  80
  81         for (this_char = strtok (options, ",");
  82              this_char != NULL;
  83              this_char = strtok (NULL, ",")) {
  84                 CDEBUG(D_SUPER, "this_char %s\n", this_char);
  85                 if ( (!*ost && (*ost = ll_read_opt("osc", this_char)))||
  86                      (!*mds && (*mds = ll_read_opt("mdc", this_char)))||
  87                      (!(*flags & LL_SBI_NOLCK) && ((*flags) = (*flags) |
  88                       ll_set_opt("nolock", this_char, LL_SBI_NOLCK))) )
  89                         continue;
  90         }
  91         EXIT;
  92 }
  93
  94 #ifndef log2
  95 #define log2(n) ffz(~(n))
  96 #endif
  97
  98 static struct super_block *ll_read_super(struct super_block *sb,
  99                                          void *data, int silent)
 100 {
 101         struct inode *root = 0;
 102         struct obd_device *obd;
 103         struct ll_sb_info *sbi;
 104         char *osc = NULL;
 105         char *mdc = NULL;
 106         int err;
 107         struct ll_fid rootfid;
 108         struct obd_statfs osfs;
 109         struct ptlrpc_request *request = NULL;
 110         struct ptlrpc_connection *mdc_conn;
 111         struct ll_read_inode2_cookie lic;
 112         class_uuid_t uuid;
 113
 114         ENTRY;
 115
 116         OBD_ALLOC(sbi, sizeof(*sbi));
 117         if (!sbi)
 118                 RETURN(NULL);
 119
 120         INIT_LIST_HEAD(&sbi->ll_conn_chain);
 121         INIT_LIST_HEAD(&sbi->ll_orphan_dentry_list);
 122         generate_random_uuid(uuid);
 123         class_uuid_unparse(uuid, sbi->ll_sb_uuid);
 124
 125         sb->u.generic_sbp = sbi;
 126
 127         ll_options(data, &osc, &mdc, &sbi->ll_flags);
 128
 129         if (!osc) {
 130                 CERROR("no osc\n");
 131                 GOTO(out_free, sb = NULL);
 132         }
 133
 134         if (!mdc) {
 135                 CERROR("no mdc\n");
 136                 GOTO(out_free, sb = NULL);
 137         }
 138
 139         obd = class_uuid2obd(mdc);
 140         if (!obd) {
 141                 CERROR("MDC %s: not setup or attached\n", mdc);
 142                 GOTO(out_free, sb = NULL);
 143         }
 144
 145         err = obd_connect(&sbi->ll_mdc_conn, obd, sbi->ll_sb_uuid,
 146                           ptlrpc_recovd, ll_recover);
 147         if (err) {
 148                 CERROR("cannot connect to %s: rc = %d\n", mdc, err);
 149                 GOTO(out_free, sb = NULL);
 150         }
 151
 152         mdc_conn = sbi2mdc(sbi)->cl_import.imp_connection;
 153         list_add(&mdc_conn->c_sb_chain, &sbi->ll_conn_chain);
 154
 155         obd = class_uuid2obd(osc);
 156         if (!obd) {
 157                 CERROR("OSC %s: not setup or attached\n", osc);
 158                 GOTO(out_mdc, sb = NULL);
 159         }
 160
 161         err = obd_connect(&sbi->ll_osc_conn, obd, sbi->ll_sb_uuid,
 162                           ptlrpc_recovd, ll_recover);
 163         if (err) {
 164                 CERROR("cannot connect to %s: rc = %d\n", osc, err);
 165                 GOTO(out_mdc, sb = NULL);
 166         }
 167
 168         err = mdc_getstatus(&sbi->ll_mdc_conn, &rootfid);
 169         if (err) {
 170                 CERROR("cannot mds_connect: rc = %d\n", err);
 171                 GOTO(out_mdc, sb = NULL);
 172         }
 173         CDEBUG(D_SUPER, "rootfid "LPU64"\n", rootfid.id);
 174         sbi->ll_rootino = rootfid.id;
 175
 176         memset(&osfs, 0, sizeof(osfs));
 177         err = obd_statfs(&sbi->ll_mdc_conn, &osfs);
 178         sb->s_blocksize = osfs.os_bsize;
 179         sb->s_blocksize_bits = log2(osfs.os_bsize);
 180         sb->s_magic = LL_SUPER_MAGIC;
 181         sb->s_maxbytes = (1ULL << (32 + 9)) - osfs.os_bsize;
 182
 183         sb->s_op = &ll_super_operations;
 184
 185         /* make root inode */
 186         err = mdc_getattr(&sbi->ll_mdc_conn, sbi->ll_rootino, S_IFDIR,
 187                           OBD_MD_FLNOTOBD|OBD_MD_FLBLOCKS, 0, &request);
 188         if (err) {
 189                 CERROR("mdc_getattr failed for root: rc = %d\n", err);
 190                 GOTO(out_request, sb = NULL);
 191         }
 192
 193         /* initialize committed transaction callback daemon */
 194         spin_lock_init(&sbi->ll_commitcbd_lock);
 195         init_waitqueue_head(&sbi->ll_commitcbd_waitq);
 196         init_waitqueue_head(&sbi->ll_commitcbd_ctl_waitq);
 197         sbi->ll_commitcbd_flags = 0;
 198         err = ll_commitcbd_setup(sbi);
 199         if (err) {
 200                 CERROR("failed to start commit callback daemon: rc = %d\n",err);
 201                 GOTO(out_request, sb = NULL);
 202         }
 203
 204         lic.lic_body = lustre_msg_buf(request->rq_repmsg, 0);
 205         lic.lic_lmm = NULL;
 206         LASSERT(sbi->ll_rootino != 0);
 207         root = iget4(sb, sbi->ll_rootino, NULL, &lic);
 208
 209         if (root) {
 210                 sb->s_root = d_alloc_root(root);
 211         } else {
 212                 CERROR("lustre_lite: bad iget4 for root\n");
 213                 GOTO(out_cdb, sb = NULL);
 214         }
 215
 216         ptlrpc_req_finished(request);
 217         request = NULL;
 218         ll_proc_namespace(sb, osc, mdc);
 219
 220 out_dev:
 221         if (mdc)
 222                 OBD_FREE(mdc, strlen(mdc) + 1);
 223         if (osc)
 224                 OBD_FREE(osc, strlen(osc) + 1);
 225
 226         RETURN(sb);
 227
 228 out_cdb:
 229         ll_commitcbd_cleanup(sbi);
 230 out_request:
 231         ptlrpc_req_finished(request);
 232         obd_disconnect(&sbi->ll_osc_conn);
 233 out_mdc:
 234         obd_disconnect(&sbi->ll_mdc_conn);
 235 out_free:
 236         OBD_FREE(sbi, sizeof(*sbi));
 237
 238         goto out_dev;
 239 } /* ll_read_super */
 240
 241 static void ll_put_super(struct super_block *sb)
 242 {
 243         struct ll_sb_info *sbi = ll_s2sbi(sb);
 244         struct list_head *tmp, *next;
 245         struct ll_fid rootfid;
 246         ENTRY;
 247
 248         list_del(&sbi->ll_conn_chain);
 249         ll_commitcbd_cleanup(sbi);
 250         obd_disconnect(&sbi->ll_osc_conn);
 251
 252         /* NULL request to force sync on the MDS, and get the last_committed
 253          * value to flush remaining RPCs from the sending queue on client.
 254          *
 255          * XXX This should be an mdc_sync() call to sync the whole MDS fs,
 256          *     which we can call for other reasons as well.
 257          */
 258         mdc_getstatus(&sbi->ll_mdc_conn, &rootfid);
 259
 260         lprocfs_dereg_mnt(sbi->ll_proc_root);
 261         sbi->ll_proc_root = NULL;
 262
 263         obd_disconnect(&sbi->ll_mdc_conn);
 264
 265         spin_lock(&dcache_lock);
 266         list_for_each_safe(tmp, next, &sbi->ll_orphan_dentry_list) {
 267                 struct dentry *dentry = list_entry(tmp, struct dentry, d_hash);
 268                 shrink_dcache_parent(dentry);
 269         }
 270         spin_unlock(&dcache_lock);
 271
 272         OBD_FREE(sbi, sizeof(*sbi));
 273
 274         EXIT;
 275 } /* ll_put_super */
 276
 277 static void ll_clear_inode(struct inode *inode)
 278 {
 279         struct ll_sb_info *sbi = ll_i2sbi(inode);
 280         struct ll_inode_info *lli = ll_i2info(inode);
 281         int rc;
 282         ENTRY;
 283
 284         rc = mdc_cancel_unused(&sbi->ll_mdc_conn, inode, LDLM_FL_NO_CALLBACK);
 285         if (rc < 0) {
 286                 CERROR("mdc_cancel_unused: %d\n", rc);
 287                 /* XXX FIXME do something dramatic */
 288         }
 289
 290         if (lli->lli_smd) {
 291                 rc = obd_cancel_unused(&sbi->ll_osc_conn, lli->lli_smd, 0);
 292                 if (rc < 0) {
 293                         CERROR("obd_cancel_unused: %d\n", rc);
 294                         /* XXX FIXME do something dramatic */
 295                 }
 296         }
 297
 298         if (atomic_read(&inode->i_count) != 0)
 299                 CERROR("clearing in-use inode %lu: count = %d\n",
 300                        inode->i_ino, atomic_read(&inode->i_count));
 301
 302         if (lli->lli_smd)
 303                 obd_free_memmd(&sbi->ll_osc_conn, &lli->lli_smd);
 304
 305         if (lli->lli_symlink_name) {
 306                 OBD_FREE(lli->lli_symlink_name,strlen(lli->lli_symlink_name)+1);
 307                 lli->lli_symlink_name = NULL;
 308         }
 309
 310         EXIT;
 311 }
 312
 313 static void ll_delete_inode(struct inode *inode)
 314 {
 315         ENTRY;
 316         if (S_ISREG(inode->i_mode)) {
 317                 int err;
 318                 struct obdo *oa;
 319                 struct lov_stripe_md *lsm = ll_i2info(inode)->lli_smd;
 320
 321                 /* mcreate with no open */
 322                 if (!lsm)
 323                         GOTO(out, 0);
 324
 325                 if (lsm->lsm_object_id == 0) {
 326                         CERROR("This really happens\n");
 327                         /* No obdo was ever created */
 328                         GOTO(out, 0);
 329                 }
 330
 331                 oa = obdo_alloc();
 332                 if (oa == NULL)
 333                         GOTO(out, -ENOMEM);
 334
 335                 oa->o_id = lsm->lsm_object_id;
 336                 obdo_from_inode(oa, inode, OBD_MD_FLID | OBD_MD_FLTYPE);
 337
 338                 err = obd_destroy(ll_i2obdconn(inode), oa, lsm);
 339                 obdo_free(oa);
 340                 if (err)
 341                         CDEBUG(D_SUPER, "obd destroy objid "LPX64" error %d\n",
 342                                lsm->lsm_object_id, err);
 343         }
 344 out:
 345         clear_inode(inode);
 346         EXIT;
 347 }
 348
 349 /* like inode_setattr, but doesn't mark the inode dirty */
 350 static int ll_attr2inode(struct inode * inode, struct iattr * attr, int trunc)
 351 {
 352         unsigned int ia_valid = attr->ia_valid;
 353         int error = 0;
 354
 355         if ((ia_valid & ATTR_SIZE) && trunc) {
 356                 error = vmtruncate(inode, attr->ia_size);
 357                 if (error)
 358                         goto out;
 359         } else if (ia_valid & ATTR_SIZE)
 360                 inode->i_size = attr->ia_size;
 361
 362         if (ia_valid & ATTR_UID)
 363                 inode->i_uid = attr->ia_uid;
 364         if (ia_valid & ATTR_GID)
 365                 inode->i_gid = attr->ia_gid;
 366         if (ia_valid & ATTR_ATIME)
 367                 inode->i_atime = attr->ia_atime;
 368         if (ia_valid & ATTR_MTIME)
 369                 inode->i_mtime = attr->ia_mtime;
 370         if (ia_valid & ATTR_CTIME)
 371                 inode->i_ctime = attr->ia_ctime;
 372         if (ia_valid & ATTR_MODE) {
 373                 inode->i_mode = attr->ia_mode;
 374                 if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
 375                         inode->i_mode &= ~S_ISGID;
 376         }
 377 out:
 378         return error;
 379 }
 380
 381 int ll_inode_setattr(struct inode *inode, struct iattr *attr, int do_trunc)
 382 {
 383         struct ptlrpc_request *request = NULL;
 384         struct ll_sb_info *sbi = ll_i2sbi(inode);
 385         int err = 0;
 386         ENTRY;
 387
 388         /* change incore inode */
 389         ll_attr2inode(inode, attr, do_trunc);
 390
 391         /* Don't send size changes to MDS to avoid "fast EA" problems, and
 392          * also avoid a pointless RPC (we get file size from OST anyways).
 393          */
 394         attr->ia_valid &= ~ATTR_SIZE;
 395         if (attr->ia_valid) {
 396                 err = mdc_setattr(&sbi->ll_mdc_conn, inode, attr, &request);
 397                 if (err)
 398                         CERROR("mdc_setattr fails (%d)\n", err);
 399
 400                 ptlrpc_req_finished(request);
 401         }
 402
 403         RETURN(err);
 404 }
 405
 406 int ll_setattr(struct dentry *de, struct iattr *attr)
 407 {
 408         int rc = inode_change_ok(de->d_inode, attr);
 409
 410         if (rc)
 411                 return rc;
 412
 413         return ll_inode_setattr(de->d_inode, attr, 1);
 414 }
 415
 416 static int ll_statfs(struct super_block *sb, struct statfs *sfs)
 417 {
 418         struct ll_sb_info *sbi = ll_s2sbi(sb);
 419         struct obd_statfs osfs;
 420         int rc;
 421         ENTRY;
 422
 423         memset(sfs, 0, sizeof(*sfs));
 424         rc = obd_statfs(&sbi->ll_mdc_conn, &osfs);
 425         statfs_unpack(sfs, &osfs);
 426         if (rc)
 427                 CERROR("mdc_statfs fails: rc = %d\n", rc);
 428         else
 429                 CDEBUG(D_SUPER, "mdc_statfs shows blocks "LPU64"/"LPU64
 430                        " objects "LPU64"/"LPU64"\n",
 431                        osfs.os_bavail, osfs.os_blocks,
 432                        osfs.os_ffree, osfs.os_files);
 433
 434         /* temporary until mds_statfs returns statfs info for all OSTs */
 435         if (!rc) {
 436                 rc = obd_statfs(&sbi->ll_osc_conn, &osfs);
 437                 if (rc) {
 438                         CERROR("obd_statfs fails: rc = %d\n", rc);
 439                         GOTO(out, rc);
 440                 }
 441                 CDEBUG(D_SUPER, "obd_statfs shows blocks "LPU64"/"LPU64
 442                        " objects "LPU64"/"LPU64"\n",
 443                        osfs.os_bavail, osfs.os_blocks,
 444                        osfs.os_ffree, osfs.os_files);
 445
 446                 while (osfs.os_blocks > ~0UL) {
 447                         sfs->f_bsize <<= 1;
 448
 449                         osfs.os_blocks >>= 1;
 450                         osfs.os_bfree >>= 1;
 451                         osfs.os_bavail >>= 1;
 452                 }
 453                 sfs->f_blocks = osfs.os_blocks;
 454                 sfs->f_bfree = osfs.os_bfree;
 455                 sfs->f_bavail = osfs.os_bavail;
 456                 if (osfs.os_ffree < (__u64)sfs->f_ffree)
 457                         sfs->f_ffree = osfs.os_ffree;
 458         }
 459
 460 out:
 461         RETURN(rc);
 462 }
 463
 464 void ll_update_inode(struct inode *inode, struct mds_body *body)
 465 {
 466         if (body->valid & OBD_MD_FLID)
 467                 inode->i_ino = body->ino;
 468         if (body->valid & OBD_MD_FLATIME)
 469                 inode->i_atime = body->atime;
 470         if (body->valid & OBD_MD_FLMTIME)
 471                 inode->i_mtime = body->mtime;
 472         if (body->valid & OBD_MD_FLCTIME)
 473                 inode->i_ctime = body->ctime;
 474         if (body->valid & OBD_MD_FLMODE)
 475                 inode->i_mode = (inode->i_mode & S_IFMT)|(body->mode & ~S_IFMT);
 476         if (body->valid & OBD_MD_FLTYPE)
 477                 inode->i_mode = (inode->i_mode & ~S_IFMT)|(body->mode & S_IFMT);
 478         if (body->valid & OBD_MD_FLUID)
 479                 inode->i_uid = body->uid;
 480         if (body->valid & OBD_MD_FLGID)
 481                 inode->i_gid = body->gid;
 482         if (body->valid & OBD_MD_FLFLAGS)
 483                 inode->i_flags = body->flags;
 484         if (body->valid & OBD_MD_FLNLINK)
 485                 inode->i_nlink = body->nlink;
 486         if (body->valid & OBD_MD_FLGENER)
 487                 inode->i_generation = body->generation;
 488         if (body->valid & OBD_MD_FLRDEV)
 489                 inode->i_rdev = body->rdev;
 490         if (body->valid & OBD_MD_FLSIZE)
 491                 inode->i_size = body->size;
 492 }
 493
 494 static void ll_read_inode2(struct inode *inode, void *opaque)
 495 {
 496         struct ll_read_inode2_cookie *lic = opaque;
 497         struct mds_body *body = lic->lic_body;
 498         struct ll_inode_info *lli = ll_i2info(inode);
 499         ENTRY;
 500
 501         sema_init(&lli->lli_open_sem, 1);
 502         atomic_set(&lli->lli_open_count, 0);
 503
 504         /* core attributes first */
 505         ll_update_inode(inode, body);
 506
 507         LASSERT(!lli->lli_smd);
 508         if (lic && lic->lic_lmm)
 509                 obd_unpackmd(ll_i2obdconn(inode), &lli->lli_smd, lic->lic_lmm);
 510
 511         /* Get the authoritative file size */
 512         if (lli->lli_smd && (inode->i_mode & S_IFREG)) {
 513                 int rc;
 514                 LASSERT(lli->lli_smd->lsm_object_id != 0);
 515                 rc = ll_file_size(inode, lli->lli_smd);
 516                 if (rc) {
 517                         CERROR("ll_file_size: %d\n", rc);
 518                         ll_clear_inode(inode);
 519                         make_bad_inode(inode);
 520                 }
 521         }
 522
 523         /* OIDEBUG(inode); */
 524
 525         if (S_ISREG(inode->i_mode)) {
 526                 inode->i_op = &ll_file_inode_operations;
 527                 inode->i_fop = &ll_file_operations;
 528                 inode->i_mapping->a_ops = &ll_aops;
 529                 EXIT;
 530         } else if (S_ISDIR(inode->i_mode)) {
 531                 inode->i_op = &ll_dir_inode_operations;
 532                 inode->i_fop = &ll_dir_operations;
 533                 inode->i_mapping->a_ops = &ll_dir_aops;
 534                 EXIT;
 535         } else if (S_ISLNK(inode->i_mode)) {
 536                 inode->i_op = &ll_fast_symlink_inode_operations;
 537                 EXIT;
 538         } else {
 539                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 540                 EXIT;
 541         }
 542 }
 543
 544 static inline void invalidate_request_list(struct list_head *req_list)
 545 {
 546         struct list_head *tmp, *n;
 547         list_for_each_safe(tmp, n, req_list) {
 548                 struct ptlrpc_request *req =
 549                         list_entry(tmp, struct ptlrpc_request, rq_list);
 550                 CERROR("invalidating req xid "LPU64" op %d to %s:%d\n",
 551                        req->rq_xid, req->rq_reqmsg->opc,
 552                        req->rq_connection->c_remote_uuid,
 553                        req->rq_import->imp_client->cli_request_portal);
 554                 req->rq_flags |= PTL_RPC_FL_ERR;
 555                 wake_up(&req->rq_wait_for_rep);
 556         }
 557 }
 558
 559 void ll_umount_begin(struct super_block *sb)
 560 {
 561         struct ll_sb_info *sbi = ll_s2sbi(sb);
 562         struct list_head *ctmp;
 563
 564         ENTRY;
 565
 566         list_for_each(ctmp, &sbi->ll_conn_chain) {
 567                 struct ptlrpc_connection *conn;
 568                 conn = list_entry(ctmp, struct ptlrpc_connection, c_sb_chain);
 569
 570                 spin_lock(&conn->c_lock);
 571                 /* XXX should just be dealing with imports, probably through
 572                  * XXX iocontrol, need next-gen recovery! */
 573                 conn->c_flags |= CONN_INVALID;
 574                 /* invalidate_request_list(&conn->c_sending_head); */
 575                 invalidate_request_list(&conn->c_delayed_head);
 576                 spin_unlock(&conn->c_lock);
 577         }
 578
 579         EXIT;
 580 }
 581
 582 /* exported operations */
 583 struct super_operations ll_super_operations =
 584 {
 585         read_inode2: ll_read_inode2,
 586         clear_inode: ll_clear_inode,
 587         delete_inode: ll_delete_inode,
 588         put_super: ll_put_super,
 589         statfs: ll_statfs,
 590         umount_begin: ll_umount_begin
 591 };
 592
 593 static struct file_system_type lustre_lite_fs_type = {
 594         name:           "lustre_lite",
 595         fs_flags:       0,
 596         read_super:     ll_read_super,
 597         owner:          THIS_MODULE,
 598 };
 599
 600 static int __init init_lustre_lite(void)
 601 {
 602         printk(KERN_INFO "Lustre Lite 0.5.14, info@clusterfs.com\n");
 603         ll_file_data_slab = kmem_cache_create("ll_file_data",
 604                                               sizeof(struct ll_file_data), 0,
 605                                               SLAB_HWCACHE_ALIGN, NULL, NULL);
 606         if (ll_file_data_slab == NULL)
 607                 return -ENOMEM;
 608         return register_filesystem(&lustre_lite_fs_type);
 609 }
 610
 611 static void __exit exit_lustre_lite(void)
 612 {
 613         unregister_filesystem(&lustre_lite_fs_type);
 614         kmem_cache_destroy(ll_file_data_slab);
 615 }
 616
 617 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
 618 MODULE_DESCRIPTION("Lustre Lite Client File System v1.0");
 619 MODULE_LICENSE("GPL");
 620
 621 module_init(init_lustre_lite);
 622 module_exit(exit_lustre_lite);
 623 #endif