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/lustre_lite.h>
  17 #include <linux/lustre_ha.h>
  18 #include <linux/obd_lov.h>
  19 #include <linux/lustre_dlm.h>
  20 #include <linux/init.h>
  21 #include <linux/fs.h>
  22
  23 kmem_cache_t *ll_file_data_slab;
  24 extern struct address_space_operations ll_aops;
  25 extern struct address_space_operations ll_dir_aops;
  26 struct super_operations ll_super_operations;
  27
  28 extern int ll_recover(struct recovd_data *, int);
  29 extern int ll_commitcbd_setup(struct ll_sb_info *);
  30 extern int ll_commitcbd_cleanup(struct ll_sb_info *);
  31
  32 static char *ll_read_opt(const char *opt, char *data)
  33 {
  34         char *value;
  35         char *retval;
  36         ENTRY;
  37
  38         CDEBUG(D_SUPER, "option: %s, data %s\n", opt, data);
  39         if ( strncmp(opt, data, strlen(opt)) )
  40                 RETURN(NULL);
  41         if ( (value = strchr(data, '=')) == NULL )
  42                 RETURN(NULL);
  43
  44         value++;
  45         OBD_ALLOC(retval, strlen(value) + 1);
  46         if ( !retval ) {
  47                 CERROR("out of memory!\n");
  48                 RETURN(NULL);
  49         }
  50
  51         memcpy(retval, value, strlen(value)+1);
  52         CDEBUG(D_SUPER, "Assigned option: %s, value %s\n", opt, retval);
  53         RETURN(retval);
  54 }
  55
  56 static int ll_set_opt(const char *opt, char *data, int fl)
  57 {
  58         ENTRY;
  59
  60         CDEBUG(D_SUPER, "option: %s, data %s\n", opt, data);
  61         if ( strncmp(opt, data, strlen(opt)) )
  62                 RETURN(0);
  63         else
  64                 RETURN(fl);
  65 }
  66
  67 static void ll_options(char *options, char **ost, char **mds, int *flags)
  68 {
  69         char *this_char;
  70         ENTRY;
  71
  72         if (!options) {
  73                 EXIT;
  74                 return;
  75         }
  76
  77         for (this_char = strtok (options, ",");
  78              this_char != NULL;
  79              this_char = strtok (NULL, ",")) {
  80                 CDEBUG(D_SUPER, "this_char %s\n", this_char);
  81                 if ( (!*ost && (*ost = ll_read_opt("osc", this_char)))||
  82                      (!*mds && (*mds = ll_read_opt("mdc", this_char)))||
  83                      (!(*flags & LL_SBI_NOLCK) && ((*flags) = (*flags) |
  84                       ll_set_opt("nolock", this_char, LL_SBI_NOLCK))) )
  85                         continue;
  86         }
  87         EXIT;
  88 }
  89
  90 #ifndef log2
  91 #define log2(n) ffz(~(n))
  92 #endif
  93
  94 static struct super_block * ll_read_super(struct super_block *sb,
  95                                           void *data, int silent)
  96 {
  97         struct inode *root = 0;
  98         struct obd_device *obd;
  99         struct ll_sb_info *sbi;
 100         char *osc = NULL;
 101         char *mdc = NULL;
 102         int err;
 103         struct ll_fid rootfid;
 104         struct obd_statfs osfs;
 105         __u64 last_committed;
 106         __u64 last_xid;
 107         struct ptlrpc_request *request = NULL;
 108         struct ptlrpc_connection *mdc_conn;
 109         struct ll_read_inode2_cookie lic;
 110         class_uuid_t uuid;
 111
 112         ENTRY;
 113         MOD_INC_USE_COUNT;
 114
 115         OBD_ALLOC(sbi, sizeof(*sbi));
 116         if (!sbi) {
 117                 MOD_DEC_USE_COUNT;
 118                 RETURN(NULL);
 119         }
 120
 121         INIT_LIST_HEAD(&sbi->ll_conn_chain);
 122         sbi->ll_mount_epoch = 0;
 123         generate_random_uuid(uuid);
 124         class_uuid_unparse(uuid, sbi->ll_sb_uuid);
 125
 126         sb->u.generic_sbp = sbi;
 127
 128         ll_options(data, &osc, &mdc, &sbi->ll_flags);
 129
 130         if (!osc) {
 131                 CERROR("no osc\n");
 132                 GOTO(out_free, sb = NULL);
 133         }
 134
 135         if (!mdc) {
 136                 CERROR("no mdc\n");
 137                 GOTO(out_free, sb = NULL);
 138         }
 139
 140         obd = class_uuid2obd(mdc);
 141         if (!obd) {
 142                 CERROR("MDC %s: not setup or attached\n", mdc);
 143                 GOTO(out_free, sb = NULL);
 144         }
 145
 146         err = obd_connect(&sbi->ll_mdc_conn, obd, sbi->ll_sb_uuid);
 147         if (err) {
 148                 CERROR("cannot connect to %s: rc = %d\n", mdc, err);
 149                 GOTO(out_free, sb = NULL);
 150         }
 151
 152 #warning Peter: is this the right place to raise the connection level?
 153         mdc_conn = sbi2mdc(sbi)->cl_import.imp_connection;
 154         mdc_conn->c_level = LUSTRE_CONN_FULL;
 155         list_add(&mdc_conn->c_sb_chain, &sbi->ll_conn_chain);
 156         spin_lock(&ptlrpc_recovd->recovd_lock);
 157         recovd_conn_manage(class_conn2export(&sbi->ll_mdc_conn)->exp_connection,
 158                            ptlrpc_recovd, ll_recover);
 159         spin_unlock(&ptlrpc_recovd->recovd_lock);
 160
 161         obd = class_uuid2obd(osc);
 162         if (!obd) {
 163                 CERROR("OSC %s: not setup or attached\n", osc);
 164                 GOTO(out_mdc, sb = NULL);
 165         }
 166
 167         err = obd_connect(&sbi->ll_osc_conn, obd, sbi->ll_sb_uuid);
 168         if (err) {
 169                 CERROR("cannot connect to %s: rc = %d\n", osc, err);
 170                 GOTO(out_mdc, sb = NULL);
 171         }
 172         spin_lock(&ptlrpc_recovd->recovd_lock);
 173         recovd_conn_manage(class_conn2export(&sbi->ll_osc_conn)->exp_connection,
 174                            ptlrpc_recovd, ll_recover);
 175         spin_unlock(&ptlrpc_recovd->recovd_lock);
 176
 177         /* XXX: need to store the last_* values somewhere */
 178         err = mdc_getstatus(&sbi->ll_mdc_conn, &rootfid, &last_committed,
 179                             &last_xid, &request);
 180         ptlrpc_req_finished(request);
 181         if (err) {
 182                 CERROR("cannot mds_connect: rc = %d\n", err);
 183                 GOTO(out_mdc, sb = NULL);
 184         }
 185         CDEBUG(D_SUPER, "rootfid %Ld\n", (unsigned long long)rootfid.id);
 186         sbi->ll_rootino = rootfid.id;
 187
 188         memset(&osfs, 0, sizeof(osfs));
 189         request = NULL;
 190         err = mdc_statfs(&sbi->ll_mdc_conn, &osfs, &request);
 191         ptlrpc_req_finished(request);
 192         sb->s_blocksize = osfs.os_bsize;
 193         sb->s_blocksize_bits = log2(osfs.os_bsize);
 194         sb->s_magic = LL_SUPER_MAGIC;
 195         sb->s_maxbytes = (1ULL << (32 + 9)) - osfs.os_bsize;
 196
 197         sb->s_op = &ll_super_operations;
 198
 199         /* make root inode */
 200         request = NULL;
 201         err = mdc_getattr(&sbi->ll_mdc_conn, sbi->ll_rootino, S_IFDIR,
 202                           OBD_MD_FLNOTOBD|OBD_MD_FLBLOCKS, 0, &request);
 203         if (err) {
 204                 CERROR("mdc_getattr failed for root: rc = %d\n", err);
 205                 GOTO(out_request, sb = NULL);
 206         }
 207
 208         /* initialize committed transaction callback daemon */
 209         spin_lock_init(&sbi->ll_commitcbd_lock);
 210         init_waitqueue_head(&sbi->ll_commitcbd_waitq);
 211         init_waitqueue_head(&sbi->ll_commitcbd_ctl_waitq);
 212         sbi->ll_commitcbd_flags = 0;
 213         err = ll_commitcbd_setup(sbi);
 214         if (err) {
 215                 CERROR("failed to start commit callback daemon: rc = %d\n",err);
 216                 GOTO(out_request, sb = NULL);
 217         }
 218
 219         lic.lic_body = lustre_msg_buf(request->rq_repmsg, 0);
 220         lic.lic_lmm = NULL;
 221         root = iget4(sb, sbi->ll_rootino, NULL, &lic);
 222
 223         if (root) {
 224                 sb->s_root = d_alloc_root(root);
 225         } else {
 226                 CERROR("lustre_lite: bad iget4 for root\n");
 227                 GOTO(out_cdb, sb = NULL);
 228         }
 229
 230         ptlrpc_req_finished(request);
 231
 232 out_dev:
 233         if (mdc)
 234                 OBD_FREE(mdc, strlen(mdc) + 1);
 235         if (osc)
 236                 OBD_FREE(osc, strlen(osc) + 1);
 237
 238         RETURN(sb);
 239
 240 out_cdb:
 241         ll_commitcbd_cleanup(sbi);
 242 out_request:
 243         ptlrpc_req_finished(request);
 244         obd_disconnect(&sbi->ll_osc_conn);
 245 out_mdc:
 246         obd_disconnect(&sbi->ll_mdc_conn);
 247 out_free:
 248         OBD_FREE(sbi, sizeof(*sbi));
 249
 250         MOD_DEC_USE_COUNT;
 251         goto out_dev;
 252 } /* ll_read_super */
 253
 254 static void ll_put_super(struct super_block *sb)
 255 {
 256         struct ll_sb_info *sbi = ll_s2sbi(sb);
 257
 258         ENTRY;
 259         list_del(&sbi->ll_conn_chain);
 260         ll_commitcbd_cleanup(sbi);
 261         obd_disconnect(&sbi->ll_osc_conn);
 262         obd_disconnect(&sbi->ll_mdc_conn);
 263         OBD_FREE(sbi, sizeof(*sbi));
 264
 265         MOD_DEC_USE_COUNT;
 266         EXIT;
 267 } /* ll_put_super */
 268
 269 static void ll_clear_inode(struct inode *inode)
 270 {
 271         ENTRY;
 272
 273         if (atomic_read(&inode->i_count) == 0) {
 274                 struct ll_inode_info *lli = ll_i2info(inode);
 275                 struct lov_stripe_md *lsm = lli->lli_smd;
 276                 char *symlink_name = lli->lli_symlink_name;
 277
 278                 if (lsm) {
 279                         OBD_FREE(lsm, ll_ost_easize(inode->i_sb));
 280                         lli->lli_smd = NULL;
 281                 }
 282                 if (symlink_name) {
 283                         OBD_FREE(symlink_name, strlen(symlink_name) + 1);
 284                         lli->lli_symlink_name = NULL;
 285                 }
 286         }
 287         EXIT;
 288 }
 289
 290 static void ll_delete_inode(struct inode *inode)
 291 {
 292         ENTRY;
 293         if (S_ISREG(inode->i_mode)) {
 294                 int err;
 295                 struct obdo *oa;
 296                 struct lov_stripe_md *lsm = ll_i2info(inode)->lli_smd;
 297
 298                 if (!lsm)
 299                         GOTO(out, -EINVAL);
 300
 301                 if (lsm->lsm_object_id == 0) {
 302                         CERROR("This really happens\n");
 303                         /* No obdo was ever created */
 304                         GOTO(out, 0);
 305                 }
 306
 307                 oa = obdo_alloc();
 308                 if (oa == NULL)
 309                         GOTO(out, -ENOMEM);
 310
 311                 oa->o_id = lsm->lsm_object_id;
 312                 oa->o_easize = ll_mds_easize(inode->i_sb);
 313                 oa->o_mode = inode->i_mode;
 314                 oa->o_valid = OBD_MD_FLID | OBD_MD_FLEASIZE | OBD_MD_FLTYPE;
 315
 316                 err = obd_destroy(ll_i2obdconn(inode), oa, lsm);
 317                 obdo_free(oa);
 318                 CDEBUG(D_SUPER, "obd destroy of objid "LPX64" error %d\n",
 319                        lsm->lsm_object_id, err);
 320         }
 321 out:
 322         clear_inode(inode);
 323         EXIT;
 324 }
 325
 326 /* like inode_setattr, but doesn't mark the inode dirty */
 327 static int ll_attr2inode(struct inode * inode, struct iattr * attr, int trunc)
 328 {
 329         unsigned int ia_valid = attr->ia_valid;
 330         int error = 0;
 331
 332         if ((ia_valid & ATTR_SIZE) && trunc) {
 333                 error = vmtruncate(inode, attr->ia_size);
 334                 if (error)
 335                         goto out;
 336         } else if (ia_valid & ATTR_SIZE)
 337                 inode->i_size = attr->ia_size;
 338
 339         if (ia_valid & ATTR_UID)
 340                 inode->i_uid = attr->ia_uid;
 341         if (ia_valid & ATTR_GID)
 342                 inode->i_gid = attr->ia_gid;
 343         if (ia_valid & ATTR_ATIME)
 344                 inode->i_atime = attr->ia_atime;
 345         if (ia_valid & ATTR_MTIME)
 346                 inode->i_mtime = attr->ia_mtime;
 347         if (ia_valid & ATTR_CTIME)
 348                 inode->i_ctime = attr->ia_ctime;
 349         if (ia_valid & ATTR_MODE) {
 350                 inode->i_mode = attr->ia_mode;
 351                 if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
 352                         inode->i_mode &= ~S_ISGID;
 353         }
 354 out:
 355         return error;
 356 }
 357
 358 int ll_inode_setattr(struct inode *inode, struct iattr *attr, int do_trunc)
 359 {
 360         struct ptlrpc_request *request = NULL;
 361         struct ll_sb_info *sbi = ll_i2sbi(inode);
 362         int err;
 363
 364         ENTRY;
 365
 366         /* change incore inode */
 367         ll_attr2inode(inode, attr, do_trunc);
 368
 369         err = mdc_setattr(&sbi->ll_mdc_conn, inode, attr, &request);
 370         if (err)
 371                 CERROR("mdc_setattr fails (%d)\n", err);
 372
 373         ptlrpc_req_finished(request);
 374
 375         RETURN(err);
 376 }
 377
 378 int ll_setattr(struct dentry *de, struct iattr *attr)
 379 {
 380         int rc = inode_change_ok(de->d_inode, attr);
 381
 382         if (rc)
 383                 return rc;
 384
 385         return ll_inode_setattr(de->d_inode, attr, 1);
 386 }
 387
 388 static int ll_statfs(struct super_block *sb, struct statfs *sfs)
 389 {
 390         struct ptlrpc_request *request = NULL;
 391         struct ll_sb_info *sbi = ll_s2sbi(sb);
 392         struct obd_statfs osfs;
 393         int rc;
 394         ENTRY;
 395
 396         memset(sfs, 0, sizeof(*sfs));
 397         rc = mdc_statfs(&sbi->ll_mdc_conn, &osfs, &request);
 398         statfs_unpack(sfs, &osfs);
 399         ptlrpc_req_finished(request);
 400         if (rc)
 401                 CERROR("mdc_statfs fails: rc = %d\n", rc);
 402         else
 403                 CDEBUG(D_SUPER, "mdc_statfs shows blocks "LPU64"/"LPU64
 404                        " objects "LPU64"/"LPU64"\n",
 405                        osfs.os_bavail, osfs.os_blocks,
 406                        osfs.os_ffree, osfs.os_files);
 407
 408         /* temporary until mds_statfs returns statfs info for all OSTs */
 409         if (!rc) {
 410                 rc = obd_statfs(&sbi->ll_osc_conn, &osfs);
 411                 if (rc) {
 412                         CERROR("obd_statfs fails: rc = %d\n", rc);
 413                         GOTO(out, rc);
 414                 }
 415                 CDEBUG(D_SUPER, "obd_statfs shows blocks "LPU64"/"LPU64
 416                        " objects "LPU64"/"LPU64"\n",
 417                        osfs.os_bavail, osfs.os_blocks,
 418                        osfs.os_ffree, osfs.os_files);
 419
 420                 while (osfs.os_blocks > ~0UL) {
 421                         sfs->f_bsize <<= 1;
 422
 423                         osfs.os_blocks >>= 1;
 424                         osfs.os_bfree >>= 1;
 425                         osfs.os_bavail >>= 1;
 426                 }
 427                 sfs->f_blocks = osfs.os_blocks;
 428                 sfs->f_bfree = osfs.os_bfree;
 429                 sfs->f_bavail = osfs.os_bavail;
 430                 if (osfs.os_ffree < (__u64)sfs->f_ffree)
 431                         sfs->f_ffree = osfs.os_ffree;
 432         }
 433
 434 out:
 435         RETURN(rc);
 436 }
 437
 438 void ll_update_inode(struct inode *inode, struct mds_body *body)
 439 {
 440         if (body->valid & OBD_MD_FLID)
 441                 inode->i_ino = body->ino;
 442         if (body->valid & OBD_MD_FLATIME)
 443                 inode->i_atime = body->atime;
 444         if (body->valid & OBD_MD_FLMTIME)
 445                 inode->i_mtime = body->mtime;
 446         if (body->valid & OBD_MD_FLCTIME)
 447                 inode->i_ctime = body->ctime;
 448         if (body->valid & OBD_MD_FLMODE)
 449                 inode->i_mode = (inode->i_mode & S_IFMT)|(body->mode & ~S_IFMT);
 450         if (body->valid & OBD_MD_FLTYPE)
 451                 inode->i_mode = (inode->i_mode & ~S_IFMT)|(body->mode & S_IFMT);
 452         if (body->valid & OBD_MD_FLUID)
 453                 inode->i_uid = body->uid;
 454         if (body->valid & OBD_MD_FLGID)
 455                 inode->i_gid = body->gid;
 456         if (body->valid & OBD_MD_FLFLAGS)
 457                 inode->i_flags = body->flags;
 458         if (body->valid & OBD_MD_FLNLINK)
 459                 inode->i_nlink = body->nlink;
 460         if (body->valid & OBD_MD_FLGENER)
 461                 inode->i_generation = body->generation;
 462         if (body->valid & OBD_MD_FLRDEV)
 463                 inode->i_rdev = body->rdev;
 464         if (body->valid & OBD_MD_FLSIZE)
 465                 inode->i_size = body->size;
 466 }
 467
 468 static void ll_read_inode2(struct inode *inode, void *opaque)
 469 {
 470         struct ll_read_inode2_cookie *lic = opaque;
 471         struct mds_body *body = lic->lic_body;
 472         struct ll_inode_info *lli = ll_i2info(inode);
 473         ENTRY;
 474
 475         sema_init(&lli->lli_open_sem, 1);
 476         lli->lli_mount_epoch = ll_i2sbi(inode)->ll_mount_epoch;
 477
 478         /* core attributes first */
 479         ll_update_inode(inode, body);
 480
 481         //if (body->valid & OBD_MD_FLEASIZE)
 482         if (lic && lic->lic_lmm) {
 483                 struct lov_mds_md *lmm = lic->lic_lmm;
 484                 int size;
 485
 486                 if (lmm->lmm_easize != ll_mds_easize(inode->i_sb)) {
 487                         CERROR("Striping metadata size error %ld\n",
 488                                inode->i_ino);
 489                         LBUG();
 490                 }
 491                 size = ll_ost_easize(inode->i_sb);
 492                 OBD_ALLOC(lli->lli_smd, size);
 493                 if (!lli->lli_smd) {
 494                         CERROR("No memory for %d\n", size);
 495                         LBUG();
 496                 }
 497                 lov_unpackmd(lli->lli_smd, lmm);
 498         } else {
 499                 lli->lli_smd = NULL;
 500         }
 501
 502         /* Get the authoritative file size */
 503         if (lli->lli_smd && (inode->i_mode & S_IFREG)) {
 504                 int rc;
 505
 506                 rc = ll_file_size(inode, lli->lli_smd);
 507                 if (rc) {
 508                         CERROR("ll_file_size: %d\n", rc);
 509                         /* FIXME: need to somehow prevent inode creation */
 510                         LBUG();
 511                 }
 512         }
 513
 514         /* OIDEBUG(inode); */
 515
 516         if (S_ISREG(inode->i_mode)) {
 517                 inode->i_op = &ll_file_inode_operations;
 518                 inode->i_fop = &ll_file_operations;
 519                 inode->i_mapping->a_ops = &ll_aops;
 520                 EXIT;
 521         } else if (S_ISDIR(inode->i_mode)) {
 522                 inode->i_op = &ll_dir_inode_operations;
 523                 inode->i_fop = &ll_dir_operations;
 524                 inode->i_mapping->a_ops = &ll_dir_aops;
 525                 EXIT;
 526         } else if (S_ISLNK(inode->i_mode)) {
 527                 inode->i_op = &ll_fast_symlink_inode_operations;
 528                 EXIT;
 529         } else {
 530                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 531                 EXIT;
 532         }
 533 }
 534
 535 static inline void invalidate_request_list(struct list_head *req_list)
 536 {
 537         struct list_head *tmp, *n;
 538         list_for_each_safe(tmp, n, req_list) {
 539                 struct ptlrpc_request *req =
 540                         list_entry(tmp, struct ptlrpc_request, rq_list);
 541                 CERROR("invalidating req xid %d op %d to %s:%d\n",
 542                        (unsigned long long)req->rq_xid, req->rq_reqmsg->opc,
 543                        req->rq_connection->c_remote_uuid,
 544                        req->rq_import->imp_client->cli_request_portal);
 545                 req->rq_flags |= PTL_RPC_FL_ERR;
 546                 wake_up(&req->rq_wait_for_rep);
 547         }
 548 }
 549
 550 void ll_umount_begin(struct super_block *sb)
 551 {
 552         struct ll_sb_info *sbi = ll_s2sbi(sb);
 553         struct list_head *ctmp;
 554
 555         ENTRY;
 556
 557         list_for_each(ctmp, &sbi->ll_conn_chain) {
 558                 struct ptlrpc_connection *conn;
 559                 conn = list_entry(ctmp, struct ptlrpc_connection, c_sb_chain);
 560
 561                 spin_lock(&conn->c_lock);
 562                 conn->c_flags |= CONN_INVALID;
 563                 invalidate_request_list(&conn->c_sending_head);
 564                 invalidate_request_list(&conn->c_delayed_head);
 565                 spin_unlock(&conn->c_lock);
 566         }
 567
 568         EXIT;
 569 }
 570
 571 /* exported operations */
 572 struct super_operations ll_super_operations =
 573 {
 574         read_inode2: ll_read_inode2,
 575         clear_inode: ll_clear_inode,
 576         delete_inode: ll_delete_inode,
 577         put_super: ll_put_super,
 578         statfs: ll_statfs,
 579         umount_begin: ll_umount_begin
 580 };
 581
 582 struct file_system_type lustre_lite_fs_type = {
 583         "lustre_lite", 0, ll_read_super, NULL
 584 };
 585
 586 static int __init init_lustre_lite(void)
 587 {
 588         printk(KERN_INFO "Lustre Lite 0.5.14, info@clusterfs.com\n");
 589         ll_file_data_slab = kmem_cache_create("ll_file_data",
 590                                               sizeof(struct ll_file_data), 0,
 591                                               SLAB_HWCACHE_ALIGN, NULL, NULL);
 592         if (ll_file_data_slab == NULL)
 593                 return -ENOMEM;
 594         return register_filesystem(&lustre_lite_fs_type);
 595 }
 596
 597 static void __exit exit_lustre_lite(void)
 598 {
 599         unregister_filesystem(&lustre_lite_fs_type);
 600         kmem_cache_destroy(ll_file_data_slab);
 601 }
 602
 603 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
 604 MODULE_DESCRIPTION("Lustre Lite Client File System v1.0");
 605 MODULE_LICENSE("GPL");
 606
 607 module_init(init_lustre_lite);
 608 module_exit(exit_lustre_lite);