lustre/mgc/mgc_request.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2013, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/mgc/mgc_request.c
  37  *
  38  * Author: Nathan Rutman <nathan@clusterfs.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_MGC
  42 #define D_MGC D_CONFIG /*|D_WARNING*/
  43
  44 #include <linux/module.h>
  45 #include <obd_class.h>
  46 #include <lustre_dlm.h>
  47 #include <lprocfs_status.h>
  48 #include <lustre_log.h>
  49 #include <lustre_disk.h>
  50 #include <dt_object.h>
  51
  52 #include "mgc_internal.h"
  53
  54 static int mgc_name2resid(char *name, int len, struct ldlm_res_id *res_id,
  55                           int type)
  56 {
  57         __u64 resname = 0;
  58
  59         if (len > sizeof(resname)) {
  60                 CERROR("name too long: %s\n", name);
  61                 return -EINVAL;
  62         }
  63         if (len <= 0) {
  64                 CERROR("missing name: %s\n", name);
  65                 return -EINVAL;
  66         }
  67         memcpy(&resname, name, len);
  68
  69         /* Always use the same endianness for the resid */
  70         memset(res_id, 0, sizeof(*res_id));
  71         res_id->name[0] = cpu_to_le64(resname);
  72         /* XXX: unfortunately, sptlprc and config llog share one lock */
  73         switch(type) {
  74         case CONFIG_T_CONFIG:
  75         case CONFIG_T_SPTLRPC:
  76                 resname = 0;
  77                 break;
  78         case CONFIG_T_RECOVER:
  79         case CONFIG_T_PARAMS:
  80                 resname = type;
  81                 break;
  82         default:
  83                 LBUG();
  84         }
  85         res_id->name[1] = cpu_to_le64(resname);
  86         CDEBUG(D_MGC, "log %s to resid "LPX64"/"LPX64" (%.8s)\n", name,
  87                res_id->name[0], res_id->name[1], (char *)&res_id->name[0]);
  88         return 0;
  89 }
  90
  91 int mgc_fsname2resid(char *fsname, struct ldlm_res_id *res_id, int type)
  92 {
  93         /* fsname is at most 8 chars long, maybe contain "-".
  94          * e.g. "lustre", "SUN-000" */
  95         return mgc_name2resid(fsname, strlen(fsname), res_id, type);
  96 }
  97 EXPORT_SYMBOL(mgc_fsname2resid);
  98
  99 int mgc_logname2resid(char *logname, struct ldlm_res_id *res_id, int type)
 100 {
 101         char *name_end;
 102         int len;
 103
 104         /* logname consists of "fsname-nodetype".
 105          * e.g. "lustre-MDT0001", "SUN-000-client"
 106          * there is an exception: llog "params" */
 107         name_end = strrchr(logname, '-');
 108         if (!name_end)
 109                 len = strlen(logname);
 110         else
 111                 len = name_end - logname;
 112         return mgc_name2resid(logname, len, res_id, type);
 113 }
 114
 115 /********************** config llog list **********************/
 116 static CFS_LIST_HEAD(config_llog_list);
 117 static DEFINE_SPINLOCK(config_list_lock);
 118
 119 /* Take a reference to a config log */
 120 static int config_log_get(struct config_llog_data *cld)
 121 {
 122         ENTRY;
 123         atomic_inc(&cld->cld_refcount);
 124         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 125                 atomic_read(&cld->cld_refcount));
 126         RETURN(0);
 127 }
 128
 129 /* Drop a reference to a config log.  When no longer referenced,
 130    we can free the config log data */
 131 static void config_log_put(struct config_llog_data *cld)
 132 {
 133         ENTRY;
 134
 135         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 136                 atomic_read(&cld->cld_refcount));
 137         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 138
 139         /* spinlock to make sure no item with 0 refcount in the list */
 140         if (atomic_dec_and_lock(&cld->cld_refcount, &config_list_lock)) {
 141                 cfs_list_del(&cld->cld_list_chain);
 142                 spin_unlock(&config_list_lock);
 143
 144                 CDEBUG(D_MGC, "dropping config log %s\n", cld->cld_logname);
 145
 146                 if (cld->cld_recover)
 147                         config_log_put(cld->cld_recover);
 148                 if (cld->cld_sptlrpc)
 149                         config_log_put(cld->cld_sptlrpc);
 150                 if (cld->cld_params)
 151                         config_log_put(cld->cld_params);
 152                 if (cld_is_sptlrpc(cld))
 153                         sptlrpc_conf_log_stop(cld->cld_logname);
 154
 155                 class_export_put(cld->cld_mgcexp);
 156                 OBD_FREE(cld, sizeof(*cld) + strlen(cld->cld_logname) + 1);
 157         }
 158
 159         EXIT;
 160 }
 161
 162 /* Find a config log by name */
 163 static
 164 struct config_llog_data *config_log_find(char *logname,
 165                                          struct config_llog_instance *cfg)
 166 {
 167         struct config_llog_data *cld;
 168         struct config_llog_data *found = NULL;
 169         void *                   instance;
 170         ENTRY;
 171
 172         LASSERT(logname != NULL);
 173
 174         instance = cfg ? cfg->cfg_instance : NULL;
 175         spin_lock(&config_list_lock);
 176         cfs_list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 177                 /* check if instance equals */
 178                 if (instance != cld->cld_cfg.cfg_instance)
 179                         continue;
 180
 181                 /* instance may be NULL, should check name */
 182                 if (strcmp(logname, cld->cld_logname) == 0) {
 183                         found = cld;
 184                         break;
 185                 }
 186         }
 187         if (found) {
 188                 atomic_inc(&found->cld_refcount);
 189                 LASSERT(found->cld_stopping == 0 || cld_is_sptlrpc(found) == 0);
 190         }
 191         spin_unlock(&config_list_lock);
 192         RETURN(found);
 193 }
 194
 195 static
 196 struct config_llog_data *do_config_log_add(struct obd_device *obd,
 197                                            char *logname,
 198                                            int type,
 199                                            struct config_llog_instance *cfg,
 200                                            struct super_block *sb)
 201 {
 202         struct config_llog_data *cld;
 203         int                      rc;
 204         ENTRY;
 205
 206         CDEBUG(D_MGC, "do adding config log %s:%p\n", logname,
 207                cfg ? cfg->cfg_instance : 0);
 208
 209         OBD_ALLOC(cld, sizeof(*cld) + strlen(logname) + 1);
 210         if (!cld)
 211                 RETURN(ERR_PTR(-ENOMEM));
 212
 213         strcpy(cld->cld_logname, logname);
 214         if (cfg)
 215                 cld->cld_cfg = *cfg;
 216         else
 217                 cld->cld_cfg.cfg_callback = class_config_llog_handler;
 218         mutex_init(&cld->cld_lock);
 219         cld->cld_cfg.cfg_last_idx = 0;
 220         cld->cld_cfg.cfg_flags = 0;
 221         cld->cld_cfg.cfg_sb = sb;
 222         cld->cld_type = type;
 223         atomic_set(&cld->cld_refcount, 1);
 224
 225         /* Keep the mgc around until we are done */
 226         cld->cld_mgcexp = class_export_get(obd->obd_self_export);
 227
 228         if (cld_is_sptlrpc(cld)) {
 229                 sptlrpc_conf_log_start(logname);
 230                 cld->cld_cfg.cfg_obdname = obd->obd_name;
 231         }
 232
 233         rc = mgc_logname2resid(logname, &cld->cld_resid, type);
 234
 235         spin_lock(&config_list_lock);
 236         cfs_list_add(&cld->cld_list_chain, &config_llog_list);
 237         spin_unlock(&config_list_lock);
 238
 239         if (rc) {
 240                 config_log_put(cld);
 241                 RETURN(ERR_PTR(rc));
 242         }
 243
 244         if (cld_is_sptlrpc(cld)) {
 245                 rc = mgc_process_log(obd, cld);
 246                 if (rc && rc != -ENOENT)
 247                         CERROR("failed processing sptlrpc log: %d\n", rc);
 248         }
 249
 250         RETURN(cld);
 251 }
 252
 253 static struct config_llog_data *config_recover_log_add(struct obd_device *obd,
 254         char *fsname,
 255         struct config_llog_instance *cfg,
 256         struct super_block *sb)
 257 {
 258         struct config_llog_instance lcfg = *cfg;
 259         struct lustre_sb_info *lsi = s2lsi(sb);
 260         struct config_llog_data *cld;
 261         char logname[32];
 262
 263         if (IS_OST(lsi))
 264                 return NULL;
 265
 266         /* for osp-on-ost, see lustre_start_osp() */
 267         if (IS_MDT(lsi) && lcfg.cfg_instance)
 268                 return NULL;
 269
 270         /* we have to use different llog for clients and mdts for cmd
 271          * where only clients are notified if one of cmd server restarts */
 272         LASSERT(strlen(fsname) < sizeof(logname) / 2);
 273         strcpy(logname, fsname);
 274         if (IS_SERVER(lsi)) { /* mdt */
 275                 LASSERT(lcfg.cfg_instance == NULL);
 276                 lcfg.cfg_instance = sb;
 277                 strcat(logname, "-mdtir");
 278         } else {
 279                 LASSERT(lcfg.cfg_instance != NULL);
 280                 strcat(logname, "-cliir");
 281         }
 282
 283         cld = do_config_log_add(obd, logname, CONFIG_T_RECOVER, &lcfg, sb);
 284         return cld;
 285 }
 286
 287 static struct config_llog_data *config_params_log_add(struct obd_device *obd,
 288         struct config_llog_instance *cfg, struct super_block *sb)
 289 {
 290         struct config_llog_instance     lcfg = *cfg;
 291         struct config_llog_data         *cld;
 292
 293         lcfg.cfg_instance = sb;
 294
 295         cld = do_config_log_add(obd, PARAMS_FILENAME, CONFIG_T_PARAMS,
 296                                 &lcfg, sb);
 297
 298         return cld;
 299 }
 300
 301 /** Add this log to the list of active logs watched by an MGC.
 302  * Active means we're watching for updates.
 303  * We have one active log per "mount" - client instance or servername.
 304  * Each instance may be at a different point in the log.
 305  */
 306 static int config_log_add(struct obd_device *obd, char *logname,
 307                           struct config_llog_instance *cfg,
 308                           struct super_block *sb)
 309 {
 310         struct lustre_sb_info   *lsi = s2lsi(sb);
 311         struct config_llog_data *cld;
 312         struct config_llog_data *sptlrpc_cld;
 313         struct config_llog_data *params_cld;
 314         char                    seclogname[32];
 315         char                    *ptr;
 316         int                     rc;
 317         ENTRY;
 318
 319         CDEBUG(D_MGC, "adding config log %s:%p\n", logname, cfg->cfg_instance);
 320
 321         /*
 322          * for each regular log, the depended sptlrpc log name is
 323          * <fsname>-sptlrpc. multiple regular logs may share one sptlrpc log.
 324          */
 325         ptr = strrchr(logname, '-');
 326         if (ptr == NULL || ptr - logname > 8) {
 327                 CERROR("logname %s is too long\n", logname);
 328                 RETURN(-EINVAL);
 329         }
 330
 331         memcpy(seclogname, logname, ptr - logname);
 332         strcpy(seclogname + (ptr - logname), "-sptlrpc");
 333
 334         sptlrpc_cld = config_log_find(seclogname, NULL);
 335         if (sptlrpc_cld == NULL) {
 336                 sptlrpc_cld = do_config_log_add(obd, seclogname,
 337                                                 CONFIG_T_SPTLRPC, NULL, NULL);
 338                 if (IS_ERR(sptlrpc_cld)) {
 339                         CERROR("can't create sptlrpc log: %s\n", seclogname);
 340                         GOTO(out_err, rc = PTR_ERR(sptlrpc_cld));
 341                 }
 342         }
 343         params_cld = config_params_log_add(obd, cfg, sb);
 344         if (IS_ERR(params_cld)) {
 345                 rc = PTR_ERR(params_cld);
 346                 CERROR("%s: can't create params log: rc = %d\n",
 347                        obd->obd_name, rc);
 348                 GOTO(out_err1, rc);
 349         }
 350
 351         cld = do_config_log_add(obd, logname, CONFIG_T_CONFIG, cfg, sb);
 352         if (IS_ERR(cld)) {
 353                 CERROR("can't create log: %s\n", logname);
 354                 GOTO(out_err2, rc = PTR_ERR(cld));
 355         }
 356
 357         cld->cld_sptlrpc = sptlrpc_cld;
 358         cld->cld_params = params_cld;
 359
 360         LASSERT(lsi->lsi_lmd);
 361         if (!(lsi->lsi_lmd->lmd_flags & LMD_FLG_NOIR)) {
 362                 struct config_llog_data *recover_cld;
 363                 ptr = strrchr(seclogname, '-');
 364                 if (ptr != NULL) {
 365                         *ptr = 0;
 366                 }
 367                 else {
 368                         CERROR("sptlrpc log name not correct: %s", seclogname);
 369                         config_log_put(cld);
 370                         RETURN(-EINVAL);
 371                 }
 372                 recover_cld = config_recover_log_add(obd, seclogname, cfg, sb);
 373                 if (IS_ERR(recover_cld))
 374                         GOTO(out_err3, rc = PTR_ERR(recover_cld));
 375                 cld->cld_recover = recover_cld;
 376         }
 377
 378         RETURN(0);
 379
 380 out_err3:
 381         config_log_put(cld);
 382
 383 out_err2:
 384         config_log_put(params_cld);
 385
 386 out_err1:
 387         config_log_put(sptlrpc_cld);
 388
 389 out_err:
 390         RETURN(rc);
 391 }
 392
 393 DEFINE_MUTEX(llog_process_lock);
 394
 395 /** Stop watching for updates on this log.
 396  */
 397 static int config_log_end(char *logname, struct config_llog_instance *cfg)
 398 {
 399         struct config_llog_data *cld;
 400         struct config_llog_data *cld_sptlrpc = NULL;
 401         struct config_llog_data *cld_params = NULL;
 402         struct config_llog_data *cld_recover = NULL;
 403         int rc = 0;
 404         ENTRY;
 405
 406         cld = config_log_find(logname, cfg);
 407         if (cld == NULL)
 408                 RETURN(-ENOENT);
 409
 410         mutex_lock(&cld->cld_lock);
 411         /*
 412          * if cld_stopping is set, it means we didn't start the log thus
 413          * not owning the start ref. this can happen after previous umount:
 414          * the cld still hanging there waiting for lock cancel, and we
 415          * remount again but failed in the middle and call log_end without
 416          * calling start_log.
 417          */
 418         if (unlikely(cld->cld_stopping)) {
 419                 mutex_unlock(&cld->cld_lock);
 420                 /* drop the ref from the find */
 421                 config_log_put(cld);
 422                 RETURN(rc);
 423         }
 424
 425         cld->cld_stopping = 1;
 426
 427         cld_recover = cld->cld_recover;
 428         cld->cld_recover = NULL;
 429         mutex_unlock(&cld->cld_lock);
 430
 431         if (cld_recover) {
 432                 mutex_lock(&cld_recover->cld_lock);
 433                 cld_recover->cld_stopping = 1;
 434                 mutex_unlock(&cld_recover->cld_lock);
 435                 config_log_put(cld_recover);
 436         }
 437
 438         spin_lock(&config_list_lock);
 439         cld_sptlrpc = cld->cld_sptlrpc;
 440         cld->cld_sptlrpc = NULL;
 441         cld_params = cld->cld_params;
 442         cld->cld_params = NULL;
 443         spin_unlock(&config_list_lock);
 444
 445         if (cld_sptlrpc)
 446                 config_log_put(cld_sptlrpc);
 447
 448         if (cld_params) {
 449                 mutex_lock(&cld_params->cld_lock);
 450                 cld_params->cld_stopping = 1;
 451                 mutex_unlock(&cld_params->cld_lock);
 452                 config_log_put(cld_params);
 453         }
 454
 455         /* drop the ref from the find */
 456         config_log_put(cld);
 457         /* drop the start ref */
 458         config_log_put(cld);
 459
 460         CDEBUG(D_MGC, "end config log %s (%d)\n", logname ? logname : "client",
 461                rc);
 462         RETURN(rc);
 463 }
 464
 465 #ifdef LPROCFS
 466 int lprocfs_mgc_rd_ir_state(struct seq_file *m, void *data)
 467 {
 468         struct obd_device       *obd = data;
 469         struct obd_import       *imp = obd->u.cli.cl_import;
 470         struct obd_connect_data *ocd = &imp->imp_connect_data;
 471         struct config_llog_data *cld;
 472         ENTRY;
 473
 474         seq_printf(m, "imperative_recovery: %s\n",
 475                    OCD_HAS_FLAG(ocd, IMP_RECOV) ? "ENABLED" : "DISABLED");
 476         seq_printf(m, "client_state:\n");
 477
 478         spin_lock(&config_list_lock);
 479         cfs_list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 480                 if (cld->cld_recover == NULL)
 481                         continue;
 482                 seq_printf(m,  "    - { client: %s, nidtbl_version: %u }\n",
 483                                cld->cld_logname,
 484                                cld->cld_recover->cld_cfg.cfg_last_idx);
 485         }
 486         spin_unlock(&config_list_lock);
 487
 488         RETURN(0);
 489 }
 490 #endif
 491
 492 /* reenqueue any lost locks */
 493 #define RQ_RUNNING 0x1
 494 #define RQ_NOW     0x2
 495 #define RQ_LATER   0x4
 496 #define RQ_STOP    0x8
 497 static int                    rq_state = 0;
 498 static wait_queue_head_t      rq_waitq;
 499 static DECLARE_COMPLETION(rq_exit);
 500
 501 static void do_requeue(struct config_llog_data *cld)
 502 {
 503         int rc = 0;
 504         ENTRY;
 505
 506         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 507
 508         /* Do not run mgc_process_log on a disconnected export or an
 509          * export which is being disconnected. Take the client
 510          * semaphore to make the check non-racy. */
 511         down_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 512         if (cld->cld_mgcexp->exp_obd->u.cli.cl_conn_count != 0) {
 513                 CDEBUG(D_MGC, "updating log %s\n", cld->cld_logname);
 514                 rc = mgc_process_log(cld->cld_mgcexp->exp_obd, cld);
 515                 if (rc && rc != -ENOENT)
 516                         CERROR("failed processing log: %d\n", rc);
 517         } else {
 518                 CDEBUG(D_MGC, "disconnecting, won't update log %s\n",
 519                        cld->cld_logname);
 520         }
 521         up_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 522
 523         EXIT;
 524 }
 525
 526 /* this timeout represents how many seconds MGC should wait before
 527  * requeue config and recover lock to the MGS. We need to randomize this
 528  * in order to not flood the MGS.
 529  */
 530 #define MGC_TIMEOUT_MIN_SECONDS   5
 531 #define MGC_TIMEOUT_RAND_CENTISEC 0x1ff /* ~500 */
 532
 533 static int mgc_requeue_thread(void *data)
 534 {
 535         int rc = 0;
 536         ENTRY;
 537
 538         CDEBUG(D_MGC, "Starting requeue thread\n");
 539
 540         /* Keep trying failed locks periodically */
 541         spin_lock(&config_list_lock);
 542         rq_state |= RQ_RUNNING;
 543         while (1) {
 544                 struct l_wait_info lwi;
 545                 struct config_llog_data *cld, *cld_prev;
 546                 int rand = cfs_rand() & MGC_TIMEOUT_RAND_CENTISEC;
 547                 int stopped = !!(rq_state & RQ_STOP);
 548                 int to;
 549
 550                 /* Any new or requeued lostlocks will change the state */
 551                 rq_state &= ~(RQ_NOW | RQ_LATER);
 552                 spin_unlock(&config_list_lock);
 553
 554                 /* Always wait a few seconds to allow the server who
 555                    caused the lock revocation to finish its setup, plus some
 556                    random so everyone doesn't try to reconnect at once. */
 557                 to = MGC_TIMEOUT_MIN_SECONDS * HZ;
 558                 to += rand * HZ / 100; /* rand is centi-seconds */
 559                 lwi = LWI_TIMEOUT(to, NULL, NULL);
 560                 l_wait_event(rq_waitq, rq_state & RQ_STOP, &lwi);
 561
 562                 /*
 563                  * iterate & processing through the list. for each cld, process
 564                  * its depending sptlrpc cld firstly (if any) and then itself.
 565                  *
 566                  * it's guaranteed any item in the list must have
 567                  * reference > 0; and if cld_lostlock is set, at
 568                  * least one reference is taken by the previous enqueue.
 569                  */
 570                 cld_prev = NULL;
 571
 572                 spin_lock(&config_list_lock);
 573                 cfs_list_for_each_entry(cld, &config_llog_list,
 574                                         cld_list_chain) {
 575                         if (!cld->cld_lostlock)
 576                                 continue;
 577
 578                         spin_unlock(&config_list_lock);
 579
 580                         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 581
 582                         /* Whether we enqueued again or not in mgc_process_log,
 583                          * we're done with the ref from the old enqueue */
 584                         if (cld_prev)
 585                                 config_log_put(cld_prev);
 586                         cld_prev = cld;
 587
 588                         cld->cld_lostlock = 0;
 589                         if (likely(!stopped))
 590                                 do_requeue(cld);
 591
 592                         spin_lock(&config_list_lock);
 593                 }
 594                 spin_unlock(&config_list_lock);
 595                 if (cld_prev)
 596                         config_log_put(cld_prev);
 597
 598                 /* break after scanning the list so that we can drop
 599                  * refcount to losing lock clds */
 600                 if (unlikely(stopped)) {
 601                         spin_lock(&config_list_lock);
 602                         break;
 603                 }
 604
 605                 /* Wait a bit to see if anyone else needs a requeue */
 606                 lwi = (struct l_wait_info) { 0 };
 607                 l_wait_event(rq_waitq, rq_state & (RQ_NOW | RQ_STOP),
 608                              &lwi);
 609                 spin_lock(&config_list_lock);
 610         }
 611         /* spinlock and while guarantee RQ_NOW and RQ_LATER are not set */
 612         rq_state &= ~RQ_RUNNING;
 613         spin_unlock(&config_list_lock);
 614
 615         complete(&rq_exit);
 616
 617         CDEBUG(D_MGC, "Ending requeue thread\n");
 618         RETURN(rc);
 619 }
 620
 621 /* Add a cld to the list to requeue.  Start the requeue thread if needed.
 622    We are responsible for dropping the config log reference from here on out. */
 623 static void mgc_requeue_add(struct config_llog_data *cld)
 624 {
 625         ENTRY;
 626
 627         CDEBUG(D_INFO, "log %s: requeue (r=%d sp=%d st=%x)\n",
 628                 cld->cld_logname, atomic_read(&cld->cld_refcount),
 629                 cld->cld_stopping, rq_state);
 630         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 631
 632         mutex_lock(&cld->cld_lock);
 633         if (cld->cld_stopping || cld->cld_lostlock) {
 634                 mutex_unlock(&cld->cld_lock);
 635                 RETURN_EXIT;
 636         }
 637         /* this refcount will be released in mgc_requeue_thread. */
 638         config_log_get(cld);
 639         cld->cld_lostlock = 1;
 640         mutex_unlock(&cld->cld_lock);
 641
 642         /* Hold lock for rq_state */
 643         spin_lock(&config_list_lock);
 644         if (rq_state & RQ_STOP) {
 645                 spin_unlock(&config_list_lock);
 646                 cld->cld_lostlock = 0;
 647                 config_log_put(cld);
 648         } else {
 649                 rq_state |= RQ_NOW;
 650                 spin_unlock(&config_list_lock);
 651                 wake_up(&rq_waitq);
 652         }
 653         EXIT;
 654 }
 655
 656 /********************** class fns **********************/
 657 static int mgc_local_llog_init(const struct lu_env *env,
 658                                struct obd_device *obd,
 659                                struct obd_device *disk)
 660 {
 661         struct llog_ctxt        *ctxt;
 662         int                      rc;
 663
 664         ENTRY;
 665
 666         rc = llog_setup(env, obd, &obd->obd_olg, LLOG_CONFIG_ORIG_CTXT, disk,
 667                         &llog_osd_ops);
 668         if (rc)
 669                 RETURN(rc);
 670
 671         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
 672         LASSERT(ctxt);
 673         ctxt->loc_dir = obd->u.cli.cl_mgc_configs_dir;
 674         llog_ctxt_put(ctxt);
 675
 676         RETURN(0);
 677 }
 678
 679 static int mgc_local_llog_fini(const struct lu_env *env,
 680                                struct obd_device *obd)
 681 {
 682         struct llog_ctxt *ctxt;
 683
 684         ENTRY;
 685
 686         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
 687         llog_cleanup(env, ctxt);
 688
 689         RETURN(0);
 690 }
 691
 692 static int mgc_fs_setup(struct obd_device *obd, struct super_block *sb)
 693 {
 694         struct lustre_sb_info   *lsi = s2lsi(sb);
 695         struct client_obd       *cli = &obd->u.cli;
 696         struct lu_fid            rfid, fid;
 697         struct dt_object        *root, *dto;
 698         struct lu_env           *env;
 699         int                      rc = 0;
 700
 701         ENTRY;
 702
 703         LASSERT(lsi);
 704         LASSERT(lsi->lsi_dt_dev);
 705
 706         OBD_ALLOC_PTR(env);
 707         if (env == NULL)
 708                 RETURN(-ENOMEM);
 709
 710         /* The mgc fs exclusion sem. Only one fs can be setup at a time. */
 711         down(&cli->cl_mgc_sem);
 712
 713         cfs_cleanup_group_info();
 714
 715         /* Setup the configs dir */
 716         rc = lu_env_init(env, LCT_MG_THREAD);
 717         if (rc)
 718                 GOTO(out_err, rc);
 719
 720         fid.f_seq = FID_SEQ_LOCAL_NAME;
 721         fid.f_oid = 1;
 722         fid.f_ver = 0;
 723         rc = local_oid_storage_init(env, lsi->lsi_dt_dev, &fid,
 724                                     &cli->cl_mgc_los);
 725         if (rc)
 726                 GOTO(out_env, rc);
 727
 728         rc = dt_root_get(env, lsi->lsi_dt_dev, &rfid);
 729         if (rc)
 730                 GOTO(out_env, rc);
 731
 732         root = dt_locate_at(env, lsi->lsi_dt_dev, &rfid,
 733                             &cli->cl_mgc_los->los_dev->dd_lu_dev, NULL);
 734         if (unlikely(IS_ERR(root)))
 735                 GOTO(out_los, rc = PTR_ERR(root));
 736
 737         dto = local_file_find_or_create(env, cli->cl_mgc_los, root,
 738                                         MOUNT_CONFIGS_DIR,
 739                                         S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
 740         lu_object_put_nocache(env, &root->do_lu);
 741         if (IS_ERR(dto))
 742                 GOTO(out_los, rc = PTR_ERR(dto));
 743
 744         cli->cl_mgc_configs_dir = dto;
 745
 746         LASSERT(lsi->lsi_osd_exp->exp_obd->obd_lvfs_ctxt.dt);
 747         rc = mgc_local_llog_init(env, obd, lsi->lsi_osd_exp->exp_obd);
 748         if (rc)
 749                 GOTO(out_llog, rc);
 750
 751         /* We take an obd ref to insure that we can't get to mgc_cleanup
 752          * without calling mgc_fs_cleanup first. */
 753         class_incref(obd, "mgc_fs", obd);
 754
 755         /* We keep the cl_mgc_sem until mgc_fs_cleanup */
 756         EXIT;
 757 out_llog:
 758         if (rc) {
 759                 lu_object_put(env, &cli->cl_mgc_configs_dir->do_lu);
 760                 cli->cl_mgc_configs_dir = NULL;
 761         }
 762 out_los:
 763         if (rc < 0) {
 764                 local_oid_storage_fini(env, cli->cl_mgc_los);
 765                 cli->cl_mgc_los = NULL;
 766                 up(&cli->cl_mgc_sem);
 767         }
 768 out_env:
 769         lu_env_fini(env);
 770 out_err:
 771         OBD_FREE_PTR(env);
 772         return rc;
 773 }
 774
 775 static int mgc_fs_cleanup(struct obd_device *obd)
 776 {
 777         struct lu_env            env;
 778         struct client_obd       *cli = &obd->u.cli;
 779         int                      rc;
 780
 781         ENTRY;
 782
 783         LASSERT(cli->cl_mgc_los != NULL);
 784
 785         rc = lu_env_init(&env, LCT_MG_THREAD);
 786         if (rc)
 787                 GOTO(unlock, rc);
 788
 789         mgc_local_llog_fini(&env, obd);
 790
 791         lu_object_put_nocache(&env, &cli->cl_mgc_configs_dir->do_lu);
 792         cli->cl_mgc_configs_dir = NULL;
 793
 794         local_oid_storage_fini(&env, cli->cl_mgc_los);
 795         cli->cl_mgc_los = NULL;
 796         lu_env_fini(&env);
 797
 798 unlock:
 799         class_decref(obd, "mgc_fs", obd);
 800         up(&cli->cl_mgc_sem);
 801
 802         RETURN(0);
 803 }
 804
 805 static int mgc_llog_init(const struct lu_env *env, struct obd_device *obd)
 806 {
 807         struct llog_ctxt        *ctxt;
 808         int                      rc;
 809
 810         ENTRY;
 811
 812         /* setup only remote ctxt, the local disk context is switched per each
 813          * filesystem during mgc_fs_setup() */
 814         rc = llog_setup(env, obd, &obd->obd_olg, LLOG_CONFIG_REPL_CTXT, obd,
 815                         &llog_client_ops);
 816         if (rc)
 817                 RETURN(rc);
 818
 819         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
 820         LASSERT(ctxt);
 821
 822         llog_initiator_connect(ctxt);
 823         llog_ctxt_put(ctxt);
 824
 825         RETURN(0);
 826 }
 827
 828 static int mgc_llog_fini(const struct lu_env *env, struct obd_device *obd)
 829 {
 830         struct llog_ctxt *ctxt;
 831
 832         ENTRY;
 833
 834         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
 835         if (ctxt)
 836                 llog_cleanup(env, ctxt);
 837
 838         RETURN(0);
 839 }
 840
 841
 842 static atomic_t mgc_count = ATOMIC_INIT(0);
 843 static int mgc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 844 {
 845         int rc = 0;
 846         ENTRY;
 847
 848         switch (stage) {
 849         case OBD_CLEANUP_EARLY:
 850                 break;
 851         case OBD_CLEANUP_EXPORTS:
 852                 if (atomic_dec_and_test(&mgc_count)) {
 853                         int running;
 854                         /* stop requeue thread */
 855                         spin_lock(&config_list_lock);
 856                         running = rq_state & RQ_RUNNING;
 857                         if (running)
 858                                 rq_state |= RQ_STOP;
 859                         spin_unlock(&config_list_lock);
 860                         if (running) {
 861                                 wake_up(&rq_waitq);
 862                                 wait_for_completion(&rq_exit);
 863                         }
 864                 }
 865                 obd_cleanup_client_import(obd);
 866                 rc = mgc_llog_fini(NULL, obd);
 867                 if (rc != 0)
 868                         CERROR("failed to cleanup llogging subsystems\n");
 869                 break;
 870         }
 871         RETURN(rc);
 872 }
 873
 874 static int mgc_cleanup(struct obd_device *obd)
 875 {
 876         int rc;
 877         ENTRY;
 878
 879         /* COMPAT_146 - old config logs may have added profiles we don't
 880            know about */
 881         if (obd->obd_type->typ_refcnt <= 1)
 882                 /* Only for the last mgc */
 883                 class_del_profiles();
 884
 885         lprocfs_obd_cleanup(obd);
 886         ptlrpcd_decref();
 887
 888         rc = client_obd_cleanup(obd);
 889         RETURN(rc);
 890 }
 891
 892 static int mgc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 893 {
 894         int                             rc;
 895         ENTRY;
 896
 897         rc = ptlrpcd_addref();
 898         if (rc < 0)
 899                 RETURN(rc);
 900
 901         rc = client_obd_setup(obd, lcfg);
 902         if (rc)
 903                 GOTO(err_decref, rc);
 904
 905         rc = mgc_llog_init(NULL, obd);
 906         if (rc) {
 907                 CERROR("failed to setup llogging subsystems\n");
 908                 GOTO(err_cleanup, rc);
 909         }
 910
 911 #ifdef LPROCFS
 912         obd->obd_vars = lprocfs_mgc_obd_vars;
 913         lprocfs_seq_obd_setup(obd);
 914 #endif
 915         sptlrpc_lprocfs_cliobd_attach(obd);
 916
 917         if (atomic_inc_return(&mgc_count) == 1) {
 918                 rq_state = 0;
 919                 init_waitqueue_head(&rq_waitq);
 920
 921                 /* start requeue thread */
 922                 rc = PTR_ERR(kthread_run(mgc_requeue_thread, NULL,
 923                                              "ll_cfg_requeue"));
 924                 if (IS_ERR_VALUE(rc)) {
 925                         CERROR("%s: Cannot start requeue thread (%d),"
 926                                "no more log updates!\n",
 927                                obd->obd_name, rc);
 928                         GOTO(err_cleanup, rc);
 929                 }
 930                 /* rc is the task_struct pointer of mgc_requeue_thread. */
 931                 rc = 0;
 932         }
 933
 934         RETURN(rc);
 935
 936 err_cleanup:
 937         client_obd_cleanup(obd);
 938 err_decref:
 939         ptlrpcd_decref();
 940         RETURN(rc);
 941 }
 942
 943 /* based on ll_mdc_blocking_ast */
 944 static int mgc_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 945                             void *data, int flag)
 946 {
 947         struct lustre_handle lockh;
 948         struct config_llog_data *cld = (struct config_llog_data *)data;
 949         int rc = 0;
 950         ENTRY;
 951
 952         switch (flag) {
 953         case LDLM_CB_BLOCKING:
 954                 /* mgs wants the lock, give it up... */
 955                 LDLM_DEBUG(lock, "MGC blocking CB");
 956                 ldlm_lock2handle(lock, &lockh);
 957                 rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
 958                 break;
 959         case LDLM_CB_CANCELING:
 960                 /* We've given up the lock, prepare ourselves to update. */
 961                 LDLM_DEBUG(lock, "MGC cancel CB");
 962
 963                 CDEBUG(D_MGC, "Lock res "DLDLMRES" (%.8s)\n",
 964                        PLDLMRES(lock->l_resource),
 965                        (char *)&lock->l_resource->lr_name.name[0]);
 966
 967                 if (!cld) {
 968                         CDEBUG(D_INFO, "missing data, won't requeue\n");
 969                         break;
 970                 }
 971
 972                 /* held at mgc_process_log(). */
 973                 LASSERT(atomic_read(&cld->cld_refcount) > 0);
 974                 /* Are we done with this log? */
 975                 if (cld->cld_stopping) {
 976                         CDEBUG(D_MGC, "log %s: stopping, won't requeue\n",
 977                                 cld->cld_logname);
 978                         config_log_put(cld);
 979                         break;
 980                 }
 981                 /* Make sure not to re-enqueue when the mgc is stopping
 982                    (we get called from client_disconnect_export) */
 983                 if (!lock->l_conn_export ||
 984                     !lock->l_conn_export->exp_obd->u.cli.cl_conn_count) {
 985                         CDEBUG(D_MGC, "log %.8s: disconnecting, won't requeue\n",
 986                                 cld->cld_logname);
 987                         config_log_put(cld);
 988                         break;
 989                 }
 990
 991                 /* Re-enqueue now */
 992                 mgc_requeue_add(cld);
 993                 config_log_put(cld);
 994                 break;
 995         default:
 996                 LBUG();
 997         }
 998
 999         RETURN(rc);
1000 }
1001
1002 /* Not sure where this should go... */
1003 #define  MGC_ENQUEUE_LIMIT 50
1004 #define  MGC_TARGET_REG_LIMIT 10
1005 #define  MGC_SEND_PARAM_LIMIT 10
1006
1007 /* Send parameter to MGS*/
1008 static int mgc_set_mgs_param(struct obd_export *exp,
1009                              struct mgs_send_param *msp)
1010 {
1011         struct ptlrpc_request *req;
1012         struct mgs_send_param *req_msp, *rep_msp;
1013         int rc;
1014         ENTRY;
1015
1016         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1017                                         &RQF_MGS_SET_INFO, LUSTRE_MGS_VERSION,
1018                                         MGS_SET_INFO);
1019         if (!req)
1020                 RETURN(-ENOMEM);
1021
1022         req_msp = req_capsule_client_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
1023         if (!req_msp) {
1024                 ptlrpc_req_finished(req);
1025                 RETURN(-ENOMEM);
1026         }
1027
1028         memcpy(req_msp, msp, sizeof(*req_msp));
1029         ptlrpc_request_set_replen(req);
1030
1031         /* Limit how long we will wait for the enqueue to complete */
1032         req->rq_delay_limit = MGC_SEND_PARAM_LIMIT;
1033         rc = ptlrpc_queue_wait(req);
1034         if (!rc) {
1035                 rep_msp = req_capsule_server_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
1036                 memcpy(msp, rep_msp, sizeof(*rep_msp));
1037         }
1038
1039         ptlrpc_req_finished(req);
1040
1041         RETURN(rc);
1042 }
1043
1044 /* Take a config lock so we can get cancel notifications */
1045 static int mgc_enqueue(struct obd_export *exp, struct lov_stripe_md *lsm,
1046                        __u32 type, ldlm_policy_data_t *policy, __u32 mode,
1047                        __u64 *flags, void *bl_cb, void *cp_cb, void *gl_cb,
1048                        void *data, __u32 lvb_len, void *lvb_swabber,
1049                        struct lustre_handle *lockh)
1050 {
1051         struct config_llog_data *cld = (struct config_llog_data *)data;
1052         struct ldlm_enqueue_info einfo = {
1053                 .ei_type        = type,
1054                 .ei_mode        = mode,
1055                 .ei_cb_bl       = mgc_blocking_ast,
1056                 .ei_cb_cp       = ldlm_completion_ast,
1057         };
1058         struct ptlrpc_request *req;
1059         int short_limit = cld_is_sptlrpc(cld);
1060         int rc;
1061         ENTRY;
1062
1063         CDEBUG(D_MGC, "Enqueue for %s (res "LPX64")\n", cld->cld_logname,
1064                cld->cld_resid.name[0]);
1065
1066         /* We need a callback for every lockholder, so don't try to
1067            ldlm_lock_match (see rev 1.1.2.11.2.47) */
1068         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1069                                         &RQF_LDLM_ENQUEUE, LUSTRE_DLM_VERSION,
1070                                         LDLM_ENQUEUE);
1071         if (req == NULL)
1072                 RETURN(-ENOMEM);
1073
1074         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER, 0);
1075         ptlrpc_request_set_replen(req);
1076
1077         /* check if this is server or client */
1078         if (cld->cld_cfg.cfg_sb) {
1079                 struct lustre_sb_info *lsi = s2lsi(cld->cld_cfg.cfg_sb);
1080                 if (lsi && IS_SERVER(lsi))
1081                         short_limit = 1;
1082         }
1083         /* Limit how long we will wait for the enqueue to complete */
1084         req->rq_delay_limit = short_limit ? 5 : MGC_ENQUEUE_LIMIT;
1085         rc = ldlm_cli_enqueue(exp, &req, &einfo, &cld->cld_resid, NULL, flags,
1086                               NULL, 0, LVB_T_NONE, lockh, 0);
1087         /* A failed enqueue should still call the mgc_blocking_ast,
1088            where it will be requeued if needed ("grant failed"). */
1089         ptlrpc_req_finished(req);
1090         RETURN(rc);
1091 }
1092
1093 static int mgc_cancel(struct obd_export *exp, struct lov_stripe_md *md,
1094                       __u32 mode, struct lustre_handle *lockh)
1095 {
1096         ENTRY;
1097
1098         ldlm_lock_decref(lockh, mode);
1099
1100         RETURN(0);
1101 }
1102
1103 static void mgc_notify_active(struct obd_device *unused)
1104 {
1105         /* wakeup mgc_requeue_thread to requeue mgc lock */
1106         spin_lock(&config_list_lock);
1107         rq_state |= RQ_NOW;
1108         spin_unlock(&config_list_lock);
1109         wake_up(&rq_waitq);
1110
1111         /* TODO: Help the MGS rebuild nidtbl. -jay */
1112 }
1113
1114 /* Send target_reg message to MGS */
1115 static int mgc_target_register(struct obd_export *exp,
1116                                struct mgs_target_info *mti)
1117 {
1118         struct ptlrpc_request  *req;
1119         struct mgs_target_info *req_mti, *rep_mti;
1120         int                     rc;
1121         ENTRY;
1122
1123         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1124                                         &RQF_MGS_TARGET_REG, LUSTRE_MGS_VERSION,
1125                                         MGS_TARGET_REG);
1126         if (req == NULL)
1127                 RETURN(-ENOMEM);
1128
1129         req_mti = req_capsule_client_get(&req->rq_pill, &RMF_MGS_TARGET_INFO);
1130         if (!req_mti) {
1131                 ptlrpc_req_finished(req);
1132                 RETURN(-ENOMEM);
1133         }
1134
1135         memcpy(req_mti, mti, sizeof(*req_mti));
1136         ptlrpc_request_set_replen(req);
1137         CDEBUG(D_MGC, "register %s\n", mti->mti_svname);
1138         /* Limit how long we will wait for the enqueue to complete */
1139         req->rq_delay_limit = MGC_TARGET_REG_LIMIT;
1140
1141         rc = ptlrpc_queue_wait(req);
1142         if (!rc) {
1143                 rep_mti = req_capsule_server_get(&req->rq_pill,
1144                                                  &RMF_MGS_TARGET_INFO);
1145                 memcpy(mti, rep_mti, sizeof(*rep_mti));
1146                 CDEBUG(D_MGC, "register %s got index = %d\n",
1147                        mti->mti_svname, mti->mti_stripe_index);
1148         }
1149         ptlrpc_req_finished(req);
1150
1151         RETURN(rc);
1152 }
1153
1154 int mgc_set_info_async(const struct lu_env *env, struct obd_export *exp,
1155                        obd_count keylen, void *key, obd_count vallen,
1156                        void *val, struct ptlrpc_request_set *set)
1157 {
1158         int rc = -EINVAL;
1159         ENTRY;
1160
1161         /* Turn off initial_recov after we try all backup servers once */
1162         if (KEY_IS(KEY_INIT_RECOV_BACKUP)) {
1163                 struct obd_import *imp = class_exp2cliimp(exp);
1164                 int value;
1165                 if (vallen != sizeof(int))
1166                         RETURN(-EINVAL);
1167                 value = *(int *)val;
1168                 CDEBUG(D_MGC, "InitRecov %s %d/d%d:i%d:r%d:or%d:%s\n",
1169                        imp->imp_obd->obd_name, value,
1170                        imp->imp_deactive, imp->imp_invalid,
1171                        imp->imp_replayable, imp->imp_obd->obd_replayable,
1172                        ptlrpc_import_state_name(imp->imp_state));
1173                 /* Resurrect if we previously died */
1174                 if ((imp->imp_state != LUSTRE_IMP_FULL &&
1175                      imp->imp_state != LUSTRE_IMP_NEW) || value > 1)
1176                         ptlrpc_reconnect_import(imp);
1177                 RETURN(0);
1178         }
1179         /* FIXME move this to mgc_process_config */
1180         if (KEY_IS(KEY_REGISTER_TARGET)) {
1181                 struct mgs_target_info *mti;
1182                 if (vallen != sizeof(struct mgs_target_info))
1183                         RETURN(-EINVAL);
1184                 mti = (struct mgs_target_info *)val;
1185                 CDEBUG(D_MGC, "register_target %s %#x\n",
1186                        mti->mti_svname, mti->mti_flags);
1187                 rc =  mgc_target_register(exp, mti);
1188                 RETURN(rc);
1189         }
1190         if (KEY_IS(KEY_SET_FS)) {
1191                 struct super_block *sb = (struct super_block *)val;
1192
1193                 if (vallen != sizeof(struct super_block))
1194                         RETURN(-EINVAL);
1195
1196                 rc = mgc_fs_setup(exp->exp_obd, sb);
1197                 RETURN(rc);
1198         }
1199         if (KEY_IS(KEY_CLEAR_FS)) {
1200                 if (vallen != 0)
1201                         RETURN(-EINVAL);
1202                 rc = mgc_fs_cleanup(exp->exp_obd);
1203                 RETURN(rc);
1204         }
1205         if (KEY_IS(KEY_SET_INFO)) {
1206                 struct mgs_send_param *msp;
1207
1208                 msp = (struct mgs_send_param *)val;
1209                 rc =  mgc_set_mgs_param(exp, msp);
1210                 RETURN(rc);
1211         }
1212         if (KEY_IS(KEY_MGSSEC)) {
1213                 struct client_obd     *cli = &exp->exp_obd->u.cli;
1214                 struct sptlrpc_flavor  flvr;
1215
1216                 /*
1217                  * empty string means using current flavor, if which haven't
1218                  * been set yet, set it as null.
1219                  *
1220                  * if flavor has been set previously, check the asking flavor
1221                  * must match the existing one.
1222                  */
1223                 if (vallen == 0) {
1224                         if (cli->cl_flvr_mgc.sf_rpc != SPTLRPC_FLVR_INVALID)
1225                                 RETURN(0);
1226                         val = "null";
1227                         vallen = 4;
1228                 }
1229
1230                 rc = sptlrpc_parse_flavor(val, &flvr);
1231                 if (rc) {
1232                         CERROR("invalid sptlrpc flavor %s to MGS\n",
1233                                (char *) val);
1234                         RETURN(rc);
1235                 }
1236
1237                 /*
1238                  * caller already hold a mutex
1239                  */
1240                 if (cli->cl_flvr_mgc.sf_rpc == SPTLRPC_FLVR_INVALID) {
1241                         cli->cl_flvr_mgc = flvr;
1242                 } else if (memcmp(&cli->cl_flvr_mgc, &flvr,
1243                                   sizeof(flvr)) != 0) {
1244                         char    str[20];
1245
1246                         sptlrpc_flavor2name(&cli->cl_flvr_mgc,
1247                                             str, sizeof(str));
1248                         LCONSOLE_ERROR("asking sptlrpc flavor %s to MGS but "
1249                                        "currently %s is in use\n",
1250                                        (char *) val, str);
1251                         rc = -EPERM;
1252                 }
1253                 RETURN(rc);
1254         }
1255
1256         RETURN(rc);
1257 }
1258
1259 static int mgc_get_info(const struct lu_env *env, struct obd_export *exp,
1260                         __u32 keylen, void *key, __u32 *vallen, void *val,
1261                         struct lov_stripe_md *unused)
1262 {
1263         int rc = -EINVAL;
1264
1265         if (KEY_IS(KEY_CONN_DATA)) {
1266                 struct obd_import *imp = class_exp2cliimp(exp);
1267                 struct obd_connect_data *data = val;
1268
1269                 if (*vallen == sizeof(*data)) {
1270                         *data = imp->imp_connect_data;
1271                         rc = 0;
1272                 }
1273         }
1274
1275         return rc;
1276 }
1277
1278 static int mgc_import_event(struct obd_device *obd,
1279                             struct obd_import *imp,
1280                             enum obd_import_event event)
1281 {
1282         int rc = 0;
1283
1284         LASSERT(imp->imp_obd == obd);
1285         CDEBUG(D_MGC, "import event %#x\n", event);
1286
1287         switch (event) {
1288         case IMP_EVENT_DISCON:
1289                 /* MGC imports should not wait for recovery */
1290                 if (OCD_HAS_FLAG(&imp->imp_connect_data, IMP_RECOV))
1291                         ptlrpc_pinger_ir_down();
1292                 break;
1293         case IMP_EVENT_INACTIVE:
1294                 break;
1295         case IMP_EVENT_INVALIDATE: {
1296                 struct ldlm_namespace *ns = obd->obd_namespace;
1297                 ldlm_namespace_cleanup(ns, LDLM_FL_LOCAL_ONLY);
1298                 break;
1299         }
1300         case IMP_EVENT_ACTIVE:
1301                 CDEBUG(D_INFO, "%s: Reactivating import\n", obd->obd_name);
1302                 /* Clearing obd_no_recov allows us to continue pinging */
1303                 obd->obd_no_recov = 0;
1304                 mgc_notify_active(obd);
1305                 if (OCD_HAS_FLAG(&imp->imp_connect_data, IMP_RECOV))
1306                         ptlrpc_pinger_ir_up();
1307                 break;
1308         case IMP_EVENT_OCD:
1309                 break;
1310         case IMP_EVENT_DEACTIVATE:
1311         case IMP_EVENT_ACTIVATE:
1312                 break;
1313         default:
1314                 CERROR("Unknown import event %#x\n", event);
1315                 LBUG();
1316         }
1317         RETURN(rc);
1318 }
1319
1320 enum {
1321         CONFIG_READ_NRPAGES_INIT = 1 << (20 - PAGE_CACHE_SHIFT),
1322         CONFIG_READ_NRPAGES      = 4
1323 };
1324
1325 static int mgc_apply_recover_logs(struct obd_device *mgc,
1326                                   struct config_llog_data *cld,
1327                                   __u64 max_version,
1328                                   void *data, int datalen, bool mne_swab)
1329 {
1330         struct config_llog_instance *cfg = &cld->cld_cfg;
1331         struct lustre_sb_info       *lsi = s2lsi(cfg->cfg_sb);
1332         struct mgs_nidtbl_entry *entry;
1333         struct lustre_cfg       *lcfg;
1334         struct lustre_cfg_bufs   bufs;
1335         u64   prev_version = 0;
1336         char *inst;
1337         char *buf;
1338         int   bufsz;
1339         int   pos;
1340         int   rc  = 0;
1341         int   off = 0;
1342         ENTRY;
1343
1344         LASSERT(cfg->cfg_instance != NULL);
1345         LASSERT(cfg->cfg_sb == cfg->cfg_instance);
1346
1347         OBD_ALLOC(inst, PAGE_CACHE_SIZE);
1348         if (inst == NULL)
1349                 RETURN(-ENOMEM);
1350
1351         if (!IS_SERVER(lsi)) {
1352                 pos = snprintf(inst, PAGE_CACHE_SIZE, "%p", cfg->cfg_instance);
1353                 if (pos >= PAGE_CACHE_SIZE) {
1354                         OBD_FREE(inst, PAGE_CACHE_SIZE);
1355                         return -E2BIG;
1356                 }
1357         } else {
1358                 LASSERT(IS_MDT(lsi));
1359                 rc = server_name2svname(lsi->lsi_svname, inst, NULL,
1360                                         PAGE_CACHE_SIZE);
1361                 if (rc) {
1362                         OBD_FREE(inst, PAGE_CACHE_SIZE);
1363                         RETURN(-EINVAL);
1364                 }
1365                 pos = strlen(inst);
1366         }
1367
1368         ++pos;
1369         buf   = inst + pos;
1370         bufsz = PAGE_CACHE_SIZE - pos;
1371
1372         while (datalen > 0) {
1373                 int   entry_len = sizeof(*entry);
1374                 int   is_ost;
1375                 struct obd_device *obd;
1376                 char *obdname;
1377                 char *cname;
1378                 char *params;
1379                 char *uuid;
1380
1381                 rc = -EINVAL;
1382                 if (datalen < sizeof(*entry))
1383                         break;
1384
1385                 entry = (typeof(entry))(data + off);
1386
1387                 /* sanity check */
1388                 if (entry->mne_nid_type != 0) /* only support type 0 for ipv4 */
1389                         break;
1390                 if (entry->mne_nid_count == 0) /* at least one nid entry */
1391                         break;
1392                 if (entry->mne_nid_size != sizeof(lnet_nid_t))
1393                         break;
1394
1395                 entry_len += entry->mne_nid_count * entry->mne_nid_size;
1396                 if (datalen < entry_len) /* must have entry_len at least */
1397                         break;
1398
1399                 /* Keep this swab for normal mixed endian handling. LU-1644 */
1400                 if (mne_swab)
1401                         lustre_swab_mgs_nidtbl_entry(entry);
1402                 if (entry->mne_length > PAGE_CACHE_SIZE) {
1403                         CERROR("MNE too large (%u)\n", entry->mne_length);
1404                         break;
1405                 }
1406
1407                 if (entry->mne_length < entry_len)
1408                         break;
1409
1410                 off     += entry->mne_length;
1411                 datalen -= entry->mne_length;
1412                 if (datalen < 0)
1413                         break;
1414
1415                 if (entry->mne_version > max_version) {
1416                         CERROR("entry index(%lld) is over max_index(%lld)\n",
1417                                entry->mne_version, max_version);
1418                         break;
1419                 }
1420
1421                 if (prev_version >= entry->mne_version) {
1422                         CERROR("index unsorted, prev %lld, now %lld\n",
1423                                prev_version, entry->mne_version);
1424                         break;
1425                 }
1426                 prev_version = entry->mne_version;
1427
1428                 /*
1429                  * Write a string with format "nid::instance" to
1430                  * lustre/<osc|mdc>/<target>-<osc|mdc>-<instance>/import.
1431                  */
1432
1433                 is_ost = entry->mne_type == LDD_F_SV_TYPE_OST;
1434                 memset(buf, 0, bufsz);
1435                 obdname = buf;
1436                 pos = 0;
1437
1438                 /* lustre-OST0001-osc-<instance #> */
1439                 strcpy(obdname, cld->cld_logname);
1440                 cname = strrchr(obdname, '-');
1441                 if (cname == NULL) {
1442                         CERROR("mgc %s: invalid logname %s\n",
1443                                mgc->obd_name, obdname);
1444                         break;
1445                 }
1446
1447                 pos = cname - obdname;
1448                 obdname[pos] = 0;
1449                 pos += sprintf(obdname + pos, "-%s%04x",
1450                                   is_ost ? "OST" : "MDT", entry->mne_index);
1451
1452                 cname = is_ost ? "osc" : "mdc",
1453                 pos += sprintf(obdname + pos, "-%s-%s", cname, inst);
1454                 lustre_cfg_bufs_reset(&bufs, obdname);
1455
1456                 /* find the obd by obdname */
1457                 obd = class_name2obd(obdname);
1458                 if (obd == NULL) {
1459                         CDEBUG(D_INFO, "mgc %s: cannot find obdname %s\n",
1460                                mgc->obd_name, obdname);
1461                         rc = 0;
1462                         /* this is a safe race, when the ost is starting up...*/
1463                         continue;
1464                 }
1465
1466                 /* osc.import = "connection=<Conn UUID>::<target instance>" */
1467                 ++pos;
1468                 params = buf + pos;
1469                 pos += sprintf(params, "%s.import=%s", cname, "connection=");
1470                 uuid = buf + pos;
1471
1472                 down_read(&obd->u.cli.cl_sem);
1473                 if (obd->u.cli.cl_import == NULL) {
1474                         /* client does not connect to the OST yet */
1475                         up_read(&obd->u.cli.cl_sem);
1476                         rc = 0;
1477                         continue;
1478                 }
1479
1480                 /* TODO: iterate all nids to find one */
1481                 /* find uuid by nid */
1482                 rc = client_import_find_conn(obd->u.cli.cl_import,
1483                                              entry->u.nids[0],
1484                                              (struct obd_uuid *)uuid);
1485                 up_read(&obd->u.cli.cl_sem);
1486                 if (rc < 0) {
1487                         CERROR("mgc: cannot find uuid by nid %s\n",
1488                                libcfs_nid2str(entry->u.nids[0]));
1489                         break;
1490                 }
1491
1492                 CDEBUG(D_INFO, "Find uuid %s by nid %s\n",
1493                        uuid, libcfs_nid2str(entry->u.nids[0]));
1494
1495                 pos += strlen(uuid);
1496                 pos += sprintf(buf + pos, "::%u", entry->mne_instance);
1497                 LASSERT(pos < bufsz);
1498
1499                 lustre_cfg_bufs_set_string(&bufs, 1, params);
1500
1501                 rc = -ENOMEM;
1502                 lcfg = lustre_cfg_new(LCFG_PARAM, &bufs);
1503                 if (lcfg == NULL) {
1504                         CERROR("mgc: cannot allocate memory\n");
1505                         break;
1506                 }
1507
1508                 CDEBUG(D_INFO, "ir apply logs "LPD64"/"LPD64" for %s -> %s\n",
1509                        prev_version, max_version, obdname, params);
1510
1511                 rc = class_process_config(lcfg);
1512                 lustre_cfg_free(lcfg);
1513                 if (rc)
1514                         CDEBUG(D_INFO, "process config for %s error %d\n",
1515                                obdname, rc);
1516
1517                 /* continue, even one with error */
1518         }
1519
1520         OBD_FREE(inst, PAGE_CACHE_SIZE);
1521         RETURN(rc);
1522 }
1523
1524 /**
1525  * This function is called if this client was notified for target restarting
1526  * by the MGS. A CONFIG_READ RPC is going to send to fetch recovery logs.
1527  */
1528 static int mgc_process_recover_log(struct obd_device *obd,
1529                                    struct config_llog_data *cld)
1530 {
1531         struct ptlrpc_request *req = NULL;
1532         struct config_llog_instance *cfg = &cld->cld_cfg;
1533         struct mgs_config_body *body;
1534         struct mgs_config_res  *res;
1535         struct ptlrpc_bulk_desc *desc;
1536         struct page **pages;
1537         int nrpages;
1538         bool eof = true;
1539         bool mne_swab = false;
1540         int i;
1541         int ealen;
1542         int rc;
1543         ENTRY;
1544
1545         /* allocate buffer for bulk transfer.
1546          * if this is the first time for this mgs to read logs,
1547          * CONFIG_READ_NRPAGES_INIT will be used since it will read all logs
1548          * once; otherwise, it only reads increment of logs, this should be
1549          * small and CONFIG_READ_NRPAGES will be used.
1550          */
1551         nrpages = CONFIG_READ_NRPAGES;
1552         if (cfg->cfg_last_idx == 0) /* the first time */
1553                 nrpages = CONFIG_READ_NRPAGES_INIT;
1554
1555         OBD_ALLOC(pages, sizeof(*pages) * nrpages);
1556         if (pages == NULL)
1557                 GOTO(out, rc = -ENOMEM);
1558
1559         for (i = 0; i < nrpages; i++) {
1560                 pages[i] = alloc_page(GFP_IOFS);
1561                 if (pages[i] == NULL)
1562                         GOTO(out, rc = -ENOMEM);
1563         }
1564
1565 again:
1566         LASSERT(cld_is_recover(cld));
1567         LASSERT(mutex_is_locked(&cld->cld_lock));
1568         req = ptlrpc_request_alloc(class_exp2cliimp(cld->cld_mgcexp),
1569                                    &RQF_MGS_CONFIG_READ);
1570         if (req == NULL)
1571                 GOTO(out, rc = -ENOMEM);
1572
1573         rc = ptlrpc_request_pack(req, LUSTRE_MGS_VERSION, MGS_CONFIG_READ);
1574         if (rc)
1575                 GOTO(out, rc);
1576
1577         /* pack request */
1578         body = req_capsule_client_get(&req->rq_pill, &RMF_MGS_CONFIG_BODY);
1579         LASSERT(body != NULL);
1580         LASSERT(sizeof(body->mcb_name) > strlen(cld->cld_logname));
1581         if (strlcpy(body->mcb_name, cld->cld_logname, sizeof(body->mcb_name))
1582             >= sizeof(body->mcb_name))
1583                 GOTO(out, rc = -E2BIG);
1584         body->mcb_offset = cfg->cfg_last_idx + 1;
1585         body->mcb_type   = cld->cld_type;
1586         body->mcb_bits   = PAGE_CACHE_SHIFT;
1587         body->mcb_units  = nrpages;
1588
1589         /* allocate bulk transfer descriptor */
1590         desc = ptlrpc_prep_bulk_imp(req, nrpages, 1, BULK_PUT_SINK,
1591                                     MGS_BULK_PORTAL);
1592         if (desc == NULL)
1593                 GOTO(out, rc = -ENOMEM);
1594
1595         for (i = 0; i < nrpages; i++)
1596                 ptlrpc_prep_bulk_page_pin(desc, pages[i], 0, PAGE_CACHE_SIZE);
1597
1598         ptlrpc_request_set_replen(req);
1599         rc = ptlrpc_queue_wait(req);
1600         if (rc)
1601                 GOTO(out, rc);
1602
1603         res = req_capsule_server_get(&req->rq_pill, &RMF_MGS_CONFIG_RES);
1604         if (res->mcr_size < res->mcr_offset)
1605                 GOTO(out, rc = -EINVAL);
1606
1607         /* always update the index even though it might have errors with
1608          * handling the recover logs */
1609         cfg->cfg_last_idx = res->mcr_offset;
1610         eof = res->mcr_offset == res->mcr_size;
1611
1612         CDEBUG(D_INFO, "Latest version "LPD64", more %d.\n",
1613                res->mcr_offset, eof == false);
1614
1615         ealen = sptlrpc_cli_unwrap_bulk_read(req, req->rq_bulk, 0);
1616         if (ealen < 0)
1617                 GOTO(out, rc = ealen);
1618
1619         if (ealen > nrpages << PAGE_CACHE_SHIFT)
1620                 GOTO(out, rc = -EINVAL);
1621
1622         if (ealen == 0) { /* no logs transferred */
1623                 if (!eof)
1624                         rc = -EINVAL;
1625                 GOTO(out, rc);
1626         }
1627
1628         mne_swab = !!ptlrpc_rep_need_swab(req);
1629 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 2, 50, 0)
1630         /* This import flag means the server did an extra swab of IR MNE
1631          * records (fixed in LU-1252), reverse it here if needed. LU-1644 */
1632         if (unlikely(req->rq_import->imp_need_mne_swab))
1633                 mne_swab = !mne_swab;
1634 #else
1635 #warning "LU-1644: Remove old OBD_CONNECT_MNE_SWAB fixup and imp_need_mne_swab"
1636 #endif
1637
1638         for (i = 0; i < nrpages && ealen > 0; i++) {
1639                 int rc2;
1640                 void *ptr;
1641
1642                 ptr = kmap(pages[i]);
1643                 rc2 = mgc_apply_recover_logs(obd, cld, res->mcr_offset, ptr,
1644                                              min_t(int, ealen, PAGE_CACHE_SIZE),
1645                                              mne_swab);
1646                 kunmap(pages[i]);
1647                 if (rc2 < 0) {
1648                         CWARN("Process recover log %s error %d\n",
1649                               cld->cld_logname, rc2);
1650                         break;
1651                 }
1652
1653                 ealen -= PAGE_CACHE_SIZE;
1654         }
1655
1656 out:
1657         if (req)
1658                 ptlrpc_req_finished(req);
1659
1660         if (rc == 0 && !eof)
1661                 goto again;
1662
1663         if (pages) {
1664                 for (i = 0; i < nrpages; i++) {
1665                         if (pages[i] == NULL)
1666                                 break;
1667                         __free_page(pages[i]);
1668                 }
1669                 OBD_FREE(pages, sizeof(*pages) * nrpages);
1670         }
1671         return rc;
1672 }
1673
1674 /* Copy a remote log locally */
1675 static int mgc_llog_local_copy(const struct lu_env *env,
1676                                struct obd_device *obd,
1677                                struct llog_ctxt *rctxt,
1678                                struct llog_ctxt *lctxt, char *logname)
1679 {
1680         char    *temp_log;
1681         int      rc;
1682
1683         ENTRY;
1684
1685         /*
1686          * - copy it to backup using llog_backup()
1687          * - copy remote llog to logname using llog_backup()
1688          * - if failed then move bakup to logname again
1689          */
1690
1691         OBD_ALLOC(temp_log, strlen(logname) + 1);
1692         if (!temp_log)
1693                 RETURN(-ENOMEM);
1694         sprintf(temp_log, "%sT", logname);
1695
1696         /* make a copy of local llog at first */
1697         rc = llog_backup(env, obd, lctxt, lctxt, logname, temp_log);
1698         if (rc < 0 && rc != -ENOENT)
1699                 GOTO(out, rc);
1700         /* copy remote llog to the local copy */
1701         rc = llog_backup(env, obd, rctxt, lctxt, logname, logname);
1702         if (rc == -ENOENT) {
1703                 /* no remote llog, delete local one too */
1704                 llog_erase(env, lctxt, NULL, logname);
1705         } else if (rc < 0) {
1706                 /* error during backup, get local one back from the copy */
1707                 llog_backup(env, obd, lctxt, lctxt, temp_log, logname);
1708 out:
1709                 CERROR("%s: failed to copy remote log %s: rc = %d\n",
1710                        obd->obd_name, logname, rc);
1711         }
1712         llog_erase(env, lctxt, NULL, temp_log);
1713         OBD_FREE(temp_log, strlen(logname) + 1);
1714         return rc;
1715 }
1716
1717 /* local_only means it cannot get remote llogs */
1718 static int mgc_process_cfg_log(struct obd_device *mgc,
1719                                struct config_llog_data *cld, int local_only)
1720 {
1721         struct llog_ctxt        *ctxt, *lctxt = NULL;
1722         struct client_obd       *cli = &mgc->u.cli;
1723         struct lustre_sb_info   *lsi = NULL;
1724         int                      rc = 0;
1725         bool                     sptlrpc_started = false;
1726         struct lu_env           *env;
1727
1728         ENTRY;
1729
1730         LASSERT(cld);
1731         LASSERT(mutex_is_locked(&cld->cld_lock));
1732
1733         /*
1734          * local copy of sptlrpc log is controlled elsewhere, don't try to
1735          * read it up here.
1736          */
1737         if (cld_is_sptlrpc(cld) && local_only)
1738                 RETURN(0);
1739
1740         if (cld->cld_cfg.cfg_sb)
1741                 lsi = s2lsi(cld->cld_cfg.cfg_sb);
1742
1743         OBD_ALLOC_PTR(env);
1744         if (env == NULL)
1745                 RETURN(-ENOMEM);
1746
1747         rc = lu_env_init(env, LCT_MG_THREAD);
1748         if (rc)
1749                 GOTO(out_free, rc);
1750
1751         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
1752         LASSERT(ctxt);
1753
1754         lctxt = llog_get_context(mgc, LLOG_CONFIG_ORIG_CTXT);
1755
1756         /* Copy the setup log locally if we can. Don't mess around if we're
1757          * running an MGS though (logs are already local). */
1758         if (lctxt && lsi && IS_SERVER(lsi) && !IS_MGS(lsi) &&
1759             cli->cl_mgc_configs_dir != NULL &&
1760             lu2dt_dev(cli->cl_mgc_configs_dir->do_lu.lo_dev) ==
1761             lsi->lsi_dt_dev) {
1762                 if (!local_only)
1763                         /* Only try to copy log if we have the lock. */
1764                         rc = mgc_llog_local_copy(env, mgc, ctxt, lctxt,
1765                                                  cld->cld_logname);
1766                 if (local_only || rc) {
1767                         if (llog_is_empty(env, lctxt, cld->cld_logname)) {
1768                                 LCONSOLE_ERROR_MSG(0x13a, "Failed to get MGS "
1769                                                    "log %s and no local copy."
1770                                                    "\n", cld->cld_logname);
1771                                 GOTO(out_pop, rc = -ENOENT);
1772                         }
1773                         CDEBUG(D_MGC, "Failed to get MGS log %s, using local "
1774                                "copy for now, will try to update later.\n",
1775                                cld->cld_logname);
1776                 }
1777                 /* Now, whether we copied or not, start using the local llog.
1778                  * If we failed to copy, we'll start using whatever the old
1779                  * log has. */
1780                 llog_ctxt_put(ctxt);
1781                 ctxt = lctxt;
1782                 lctxt = NULL;
1783         } else {
1784                 if (local_only) /* no local log at client side */
1785                         GOTO(out_pop, rc = -EIO);
1786         }
1787
1788         if (cld_is_sptlrpc(cld)) {
1789                 sptlrpc_conf_log_update_begin(cld->cld_logname);
1790                 sptlrpc_started = true;
1791         }
1792
1793         /* logname and instance info should be the same, so use our
1794          * copy of the instance for the update.  The cfg_last_idx will
1795          * be updated here. */
1796         rc = class_config_parse_llog(env, ctxt, cld->cld_logname,
1797                                      &cld->cld_cfg);
1798         EXIT;
1799
1800 out_pop:
1801         __llog_ctxt_put(env, ctxt);
1802         if (lctxt)
1803                 __llog_ctxt_put(env, lctxt);
1804
1805         /*
1806          * update settings on existing OBDs. doing it inside
1807          * of llog_process_lock so no device is attaching/detaching
1808          * in parallel.
1809          * the logname must be <fsname>-sptlrpc
1810          */
1811         if (sptlrpc_started) {
1812                 LASSERT(cld_is_sptlrpc(cld));
1813                 sptlrpc_conf_log_update_end(cld->cld_logname);
1814                 class_notify_sptlrpc_conf(cld->cld_logname,
1815                                           strlen(cld->cld_logname) -
1816                                           strlen("-sptlrpc"));
1817         }
1818
1819         lu_env_fini(env);
1820 out_free:
1821         OBD_FREE_PTR(env);
1822         return rc;
1823 }
1824
1825 /** Get a config log from the MGS and process it.
1826  * This func is called for both clients and servers.
1827  * Copy the log locally before parsing it if appropriate (non-MGS server)
1828  */
1829 int mgc_process_log(struct obd_device *mgc, struct config_llog_data *cld)
1830 {
1831         struct lustre_handle lockh = { 0 };
1832         __u64 flags = LDLM_FL_NO_LRU;
1833         int rc = 0, rcl;
1834         ENTRY;
1835
1836         LASSERT(cld);
1837
1838         /* I don't want multiple processes running process_log at once --
1839            sounds like badness.  It actually might be fine, as long as
1840            we're not trying to update from the same log
1841            simultaneously (in which case we should use a per-log sem.) */
1842         mutex_lock(&cld->cld_lock);
1843         if (cld->cld_stopping) {
1844                 mutex_unlock(&cld->cld_lock);
1845                 RETURN(0);
1846         }
1847
1848         OBD_FAIL_TIMEOUT(OBD_FAIL_MGC_PAUSE_PROCESS_LOG, 20);
1849
1850         CDEBUG(D_MGC, "Process log %s:%p from %d\n", cld->cld_logname,
1851                cld->cld_cfg.cfg_instance, cld->cld_cfg.cfg_last_idx + 1);
1852
1853         /* Get the cfg lock on the llog */
1854         rcl = mgc_enqueue(mgc->u.cli.cl_mgc_mgsexp, NULL, LDLM_PLAIN, NULL,
1855                           LCK_CR, &flags, NULL, NULL, NULL,
1856                           cld, 0, NULL, &lockh);
1857         if (rcl == 0) {
1858                 /* Get the cld, it will be released in mgc_blocking_ast. */
1859                 config_log_get(cld);
1860                 rc = ldlm_lock_set_data(&lockh, (void *)cld);
1861                 LASSERT(rc == 0);
1862         } else {
1863                 CDEBUG(D_MGC, "Can't get cfg lock: %d\n", rcl);
1864
1865                 /* mark cld_lostlock so that it will requeue
1866                  * after MGC becomes available. */
1867                 cld->cld_lostlock = 1;
1868                 /* Get extra reference, it will be put in requeue thread */
1869                 config_log_get(cld);
1870         }
1871
1872
1873         if (cld_is_recover(cld)) {
1874                 rc = 0; /* this is not a fatal error for recover log */
1875                 if (rcl == 0)
1876                         rc = mgc_process_recover_log(mgc, cld);
1877         } else {
1878                 rc = mgc_process_cfg_log(mgc, cld, rcl != 0);
1879         }
1880
1881         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
1882                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
1883
1884         mutex_unlock(&cld->cld_lock);
1885
1886         /* Now drop the lock so MGS can revoke it */
1887         if (!rcl) {
1888                 rcl = mgc_cancel(mgc->u.cli.cl_mgc_mgsexp, NULL,
1889                                  LCK_CR, &lockh);
1890                 if (rcl)
1891                         CERROR("Can't drop cfg lock: %d\n", rcl);
1892         }
1893
1894         RETURN(rc);
1895 }
1896
1897
1898 /** Called from lustre_process_log.
1899  * LCFG_LOG_START gets the config log from the MGS, processes it to start
1900  * any services, and adds it to the list logs to watch (follow).
1901  */
1902 static int mgc_process_config(struct obd_device *obd, obd_count len, void *buf)
1903 {
1904         struct lustre_cfg *lcfg = buf;
1905         struct config_llog_instance *cfg = NULL;
1906         char *logname;
1907         int rc = 0;
1908         ENTRY;
1909
1910         switch(lcfg->lcfg_command) {
1911         case LCFG_LOV_ADD_OBD: {
1912                 /* Overloading this cfg command: register a new target */
1913                 struct mgs_target_info *mti;
1914
1915                 if (LUSTRE_CFG_BUFLEN(lcfg, 1) !=
1916                     sizeof(struct mgs_target_info))
1917                         GOTO(out, rc = -EINVAL);
1918
1919                 mti = (struct mgs_target_info *)lustre_cfg_buf(lcfg, 1);
1920                 CDEBUG(D_MGC, "add_target %s %#x\n",
1921                        mti->mti_svname, mti->mti_flags);
1922                 rc = mgc_target_register(obd->u.cli.cl_mgc_mgsexp, mti);
1923                 break;
1924         }
1925         case LCFG_LOV_DEL_OBD:
1926                 /* Unregister has no meaning at the moment. */
1927                 CERROR("lov_del_obd unimplemented\n");
1928                 rc = -ENOSYS;
1929                 break;
1930         case LCFG_SPTLRPC_CONF: {
1931                 rc = sptlrpc_process_config(lcfg);
1932                 break;
1933         }
1934         case LCFG_LOG_START: {
1935                 struct config_llog_data *cld;
1936                 struct super_block *sb;
1937
1938                 logname = lustre_cfg_string(lcfg, 1);
1939                 cfg = (struct config_llog_instance *)lustre_cfg_buf(lcfg, 2);
1940                 sb = *(struct super_block **)lustre_cfg_buf(lcfg, 3);
1941
1942                 CDEBUG(D_MGC, "parse_log %s from %d\n", logname,
1943                        cfg->cfg_last_idx);
1944
1945                 /* We're only called through here on the initial mount */
1946                 rc = config_log_add(obd, logname, cfg, sb);
1947                 if (rc)
1948                         break;
1949                 cld = config_log_find(logname, cfg);
1950                 if (cld == NULL) {
1951                         rc = -ENOENT;
1952                         break;
1953                 }
1954
1955                 /* COMPAT_146 */
1956                 /* FIXME only set this for old logs!  Right now this forces
1957                    us to always skip the "inside markers" check */
1958                 cld->cld_cfg.cfg_flags |= CFG_F_COMPAT146;
1959
1960                 rc = mgc_process_log(obd, cld);
1961                 if (rc == 0 && cld->cld_recover != NULL) {
1962                         if (OCD_HAS_FLAG(&obd->u.cli.cl_import->
1963                                          imp_connect_data, IMP_RECOV)) {
1964                                 rc = mgc_process_log(obd, cld->cld_recover);
1965                         } else {
1966                                 struct config_llog_data *cir = cld->cld_recover;
1967                                 cld->cld_recover = NULL;
1968                                 config_log_put(cir);
1969                         }
1970                         if (rc)
1971                                 CERROR("Cannot process recover llog %d\n", rc);
1972                 }
1973
1974                 if (rc == 0 && cld->cld_params != NULL) {
1975                         rc = mgc_process_log(obd, cld->cld_params);
1976                         if (rc == -ENOENT) {
1977                                 CDEBUG(D_MGC, "There is no params"
1978                                               "config file yet\n");
1979                                 rc = 0;
1980                         }
1981                         /* params log is optional */
1982                         if (rc)
1983                                 CERROR("%s: can't process params llog: rc = %d\n",
1984                                        obd->obd_name, rc);
1985                 }
1986                 config_log_put(cld);
1987
1988                 break;
1989         }
1990         case LCFG_LOG_END: {
1991                 logname = lustre_cfg_string(lcfg, 1);
1992
1993                 if (lcfg->lcfg_bufcount >= 2)
1994                         cfg = (struct config_llog_instance *)lustre_cfg_buf(
1995                                 lcfg, 2);
1996                 rc = config_log_end(logname, cfg);
1997                 break;
1998         }
1999         default: {
2000                 CERROR("Unknown command: %d\n", lcfg->lcfg_command);
2001                 GOTO(out, rc = -EINVAL);
2002
2003         }
2004         }
2005 out:
2006         RETURN(rc);
2007 }
2008
2009 struct obd_ops mgc_obd_ops = {
2010         .o_owner        = THIS_MODULE,
2011         .o_setup        = mgc_setup,
2012         .o_precleanup   = mgc_precleanup,
2013         .o_cleanup      = mgc_cleanup,
2014         .o_add_conn     = client_import_add_conn,
2015         .o_del_conn     = client_import_del_conn,
2016         .o_connect      = client_connect_import,
2017         .o_disconnect   = client_disconnect_export,
2018         //.o_enqueue      = mgc_enqueue,
2019         .o_cancel       = mgc_cancel,
2020         //.o_iocontrol    = mgc_iocontrol,
2021         .o_set_info_async = mgc_set_info_async,
2022         .o_get_info       = mgc_get_info,
2023         .o_import_event = mgc_import_event,
2024         .o_process_config = mgc_process_config,
2025 };
2026
2027 int __init mgc_init(void)
2028 {
2029         return class_register_type(&mgc_obd_ops, NULL, NULL,
2030 #ifndef HAVE_ONLY_PROCFS_SEQ
2031                                         NULL,
2032 #endif
2033                                         LUSTRE_MGC_NAME, NULL);
2034 }
2035
2036 #ifdef __KERNEL__
2037 static void /*__exit*/ mgc_exit(void)
2038 {
2039         class_unregister_type(LUSTRE_MGC_NAME);
2040 }
2041
2042 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
2043 MODULE_DESCRIPTION("Lustre Management Client");
2044 MODULE_LICENSE("GPL");
2045
2046 module_init(mgc_init);
2047 module_exit(mgc_exit);
2048 #endif