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 struct list_head config_llog_list = LIST_HEAD_INIT(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                 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         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         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("%s: sptlrpc log name not correct, %s: "
 369                                "rc = %d\n", obd->obd_name, seclogname, -EINVAL);
 370                         config_log_put(cld);
 371                         RETURN(-EINVAL);
 372                 }
 373                 recover_cld = config_recover_log_add(obd, seclogname, cfg, sb);
 374                 if (IS_ERR(recover_cld))
 375                         GOTO(out_err3, rc = PTR_ERR(recover_cld));
 376                 cld->cld_recover = recover_cld;
 377         }
 378
 379         RETURN(0);
 380
 381 out_err3:
 382         config_log_put(cld);
 383
 384 out_err2:
 385         config_log_put(params_cld);
 386
 387 out_err1:
 388         config_log_put(sptlrpc_cld);
 389
 390 out_err:
 391         RETURN(rc);
 392 }
 393
 394 DEFINE_MUTEX(llog_process_lock);
 395
 396 /** Stop watching for updates on this log.
 397  */
 398 static int config_log_end(char *logname, struct config_llog_instance *cfg)
 399 {
 400         struct config_llog_data *cld;
 401         struct config_llog_data *cld_sptlrpc = NULL;
 402         struct config_llog_data *cld_params = NULL;
 403         struct config_llog_data *cld_recover = NULL;
 404         int rc = 0;
 405         ENTRY;
 406
 407         cld = config_log_find(logname, cfg);
 408         if (cld == NULL)
 409                 RETURN(-ENOENT);
 410
 411         mutex_lock(&cld->cld_lock);
 412         /*
 413          * if cld_stopping is set, it means we didn't start the log thus
 414          * not owning the start ref. this can happen after previous umount:
 415          * the cld still hanging there waiting for lock cancel, and we
 416          * remount again but failed in the middle and call log_end without
 417          * calling start_log.
 418          */
 419         if (unlikely(cld->cld_stopping)) {
 420                 mutex_unlock(&cld->cld_lock);
 421                 /* drop the ref from the find */
 422                 config_log_put(cld);
 423                 RETURN(rc);
 424         }
 425
 426         cld->cld_stopping = 1;
 427
 428         cld_recover = cld->cld_recover;
 429         cld->cld_recover = NULL;
 430         mutex_unlock(&cld->cld_lock);
 431
 432         if (cld_recover) {
 433                 mutex_lock(&cld_recover->cld_lock);
 434                 cld_recover->cld_stopping = 1;
 435                 mutex_unlock(&cld_recover->cld_lock);
 436                 config_log_put(cld_recover);
 437         }
 438
 439         spin_lock(&config_list_lock);
 440         cld_sptlrpc = cld->cld_sptlrpc;
 441         cld->cld_sptlrpc = NULL;
 442         cld_params = cld->cld_params;
 443         cld->cld_params = NULL;
 444         spin_unlock(&config_list_lock);
 445
 446         if (cld_sptlrpc)
 447                 config_log_put(cld_sptlrpc);
 448
 449         if (cld_params) {
 450                 mutex_lock(&cld_params->cld_lock);
 451                 cld_params->cld_stopping = 1;
 452                 mutex_unlock(&cld_params->cld_lock);
 453                 config_log_put(cld_params);
 454         }
 455
 456         /* drop the ref from the find */
 457         config_log_put(cld);
 458         /* drop the start ref */
 459         config_log_put(cld);
 460
 461         CDEBUG(D_MGC, "end config log %s (%d)\n", logname ? logname : "client",
 462                rc);
 463         RETURN(rc);
 464 }
 465
 466 #ifdef LPROCFS
 467 int lprocfs_mgc_rd_ir_state(struct seq_file *m, void *data)
 468 {
 469         struct obd_device       *obd = data;
 470         struct obd_import       *imp = obd->u.cli.cl_import;
 471         struct obd_connect_data *ocd = &imp->imp_connect_data;
 472         struct config_llog_data *cld;
 473         ENTRY;
 474
 475         seq_printf(m, "imperative_recovery: %s\n",
 476                    OCD_HAS_FLAG(ocd, IMP_RECOV) ? "ENABLED" : "DISABLED");
 477         seq_printf(m, "client_state:\n");
 478
 479         spin_lock(&config_list_lock);
 480         list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 481                 if (cld->cld_recover == NULL)
 482                         continue;
 483                 seq_printf(m,  "    - { client: %s, nidtbl_version: %u }\n",
 484                                cld->cld_logname,
 485                                cld->cld_recover->cld_cfg.cfg_last_idx);
 486         }
 487         spin_unlock(&config_list_lock);
 488
 489         RETURN(0);
 490 }
 491 #endif
 492
 493 /* reenqueue any lost locks */
 494 #define RQ_RUNNING      0x1
 495 #define RQ_NOW          0x2
 496 #define RQ_LATER        0x4
 497 #define RQ_STOP         0x8
 498 #define RQ_PRECLEANUP   0x10
 499 static int                    rq_state = 0;
 500 static wait_queue_head_t      rq_waitq;
 501 static DECLARE_COMPLETION(rq_exit);
 502 static DECLARE_COMPLETION(rq_start);
 503
 504 static void do_requeue(struct config_llog_data *cld)
 505 {
 506         int rc = 0;
 507         ENTRY;
 508
 509         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 510
 511         /* Do not run mgc_process_log on a disconnected export or an
 512          * export which is being disconnected. Take the client
 513          * semaphore to make the check non-racy. */
 514         down_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 515         if (cld->cld_mgcexp->exp_obd->u.cli.cl_conn_count != 0) {
 516                 CDEBUG(D_MGC, "updating log %s\n", cld->cld_logname);
 517                 rc = mgc_process_log(cld->cld_mgcexp->exp_obd, cld);
 518                 if (rc && rc != -ENOENT)
 519                         CERROR("failed processing log: %d\n", rc);
 520         } else {
 521                 CDEBUG(D_MGC, "disconnecting, won't update log %s\n",
 522                        cld->cld_logname);
 523         }
 524         up_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 525
 526         EXIT;
 527 }
 528
 529 /* this timeout represents how many seconds MGC should wait before
 530  * requeue config and recover lock to the MGS. We need to randomize this
 531  * in order to not flood the MGS.
 532  */
 533 #define MGC_TIMEOUT_MIN_SECONDS   5
 534 #define MGC_TIMEOUT_RAND_CENTISEC 0x1ff /* ~500 */
 535
 536 static int mgc_requeue_thread(void *data)
 537 {
 538         int rc = 0;
 539         bool first = true;
 540         ENTRY;
 541
 542         CDEBUG(D_MGC, "Starting requeue thread\n");
 543
 544         /* Keep trying failed locks periodically */
 545         spin_lock(&config_list_lock);
 546         rq_state |= RQ_RUNNING;
 547         while (1) {
 548                 struct l_wait_info lwi;
 549                 struct config_llog_data *cld, *cld_prev;
 550                 int rand = cfs_rand() & MGC_TIMEOUT_RAND_CENTISEC;
 551                 int stopped = !!(rq_state & RQ_STOP);
 552                 int to;
 553
 554                 /* Any new or requeued lostlocks will change the state */
 555                 rq_state &= ~(RQ_NOW | RQ_LATER);
 556                 spin_unlock(&config_list_lock);
 557
 558                 if (first) {
 559                         first = false;
 560                         complete(&rq_start);
 561                 }
 562
 563                 /* Always wait a few seconds to allow the server who
 564                    caused the lock revocation to finish its setup, plus some
 565                    random so everyone doesn't try to reconnect at once. */
 566                 to = msecs_to_jiffies(MGC_TIMEOUT_MIN_SECONDS * MSEC_PER_SEC);
 567                 /* rand is centi-seconds */
 568                 to += msecs_to_jiffies(rand * MSEC_PER_SEC / 100);
 569                 lwi = LWI_TIMEOUT(to, NULL, NULL);
 570                 l_wait_event(rq_waitq, rq_state & (RQ_STOP | RQ_PRECLEANUP),
 571                              &lwi);
 572
 573                 /*
 574                  * iterate & processing through the list. for each cld, process
 575                  * its depending sptlrpc cld firstly (if any) and then itself.
 576                  *
 577                  * it's guaranteed any item in the list must have
 578                  * reference > 0; and if cld_lostlock is set, at
 579                  * least one reference is taken by the previous enqueue.
 580                  */
 581                 cld_prev = NULL;
 582
 583                 spin_lock(&config_list_lock);
 584                 rq_state &= ~RQ_PRECLEANUP;
 585                 list_for_each_entry(cld, &config_llog_list,
 586                                         cld_list_chain) {
 587                         if (!cld->cld_lostlock)
 588                                 continue;
 589
 590                         spin_unlock(&config_list_lock);
 591
 592                         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 593
 594                         /* Whether we enqueued again or not in mgc_process_log,
 595                          * we're done with the ref from the old enqueue */
 596                         if (cld_prev)
 597                                 config_log_put(cld_prev);
 598                         cld_prev = cld;
 599
 600                         cld->cld_lostlock = 0;
 601                         if (likely(!stopped))
 602                                 do_requeue(cld);
 603
 604                         spin_lock(&config_list_lock);
 605                 }
 606                 spin_unlock(&config_list_lock);
 607                 if (cld_prev)
 608                         config_log_put(cld_prev);
 609
 610                 /* break after scanning the list so that we can drop
 611                  * refcount to losing lock clds */
 612                 if (unlikely(stopped)) {
 613                         spin_lock(&config_list_lock);
 614                         break;
 615                 }
 616
 617                 /* Wait a bit to see if anyone else needs a requeue */
 618                 lwi = (struct l_wait_info) { 0 };
 619                 l_wait_event(rq_waitq, rq_state & (RQ_NOW | RQ_STOP),
 620                              &lwi);
 621                 spin_lock(&config_list_lock);
 622         }
 623         /* spinlock and while guarantee RQ_NOW and RQ_LATER are not set */
 624         rq_state &= ~RQ_RUNNING;
 625         spin_unlock(&config_list_lock);
 626
 627         complete(&rq_exit);
 628
 629         CDEBUG(D_MGC, "Ending requeue thread\n");
 630         RETURN(rc);
 631 }
 632
 633 /* Add a cld to the list to requeue.  Start the requeue thread if needed.
 634    We are responsible for dropping the config log reference from here on out. */
 635 static void mgc_requeue_add(struct config_llog_data *cld)
 636 {
 637         ENTRY;
 638
 639         CDEBUG(D_INFO, "log %s: requeue (r=%d sp=%d st=%x)\n",
 640                 cld->cld_logname, atomic_read(&cld->cld_refcount),
 641                 cld->cld_stopping, rq_state);
 642         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 643
 644         mutex_lock(&cld->cld_lock);
 645         if (cld->cld_stopping || cld->cld_lostlock) {
 646                 mutex_unlock(&cld->cld_lock);
 647                 RETURN_EXIT;
 648         }
 649         /* this refcount will be released in mgc_requeue_thread. */
 650         config_log_get(cld);
 651         cld->cld_lostlock = 1;
 652         mutex_unlock(&cld->cld_lock);
 653
 654         /* Hold lock for rq_state */
 655         spin_lock(&config_list_lock);
 656         if (rq_state & RQ_STOP) {
 657                 spin_unlock(&config_list_lock);
 658                 cld->cld_lostlock = 0;
 659                 config_log_put(cld);
 660         } else {
 661                 rq_state |= RQ_NOW;
 662                 spin_unlock(&config_list_lock);
 663                 wake_up(&rq_waitq);
 664         }
 665         EXIT;
 666 }
 667
 668 /********************** class fns **********************/
 669 static int mgc_local_llog_init(const struct lu_env *env,
 670                                struct obd_device *obd,
 671                                struct obd_device *disk)
 672 {
 673         struct llog_ctxt        *ctxt;
 674         int                      rc;
 675
 676         ENTRY;
 677
 678         rc = llog_setup(env, obd, &obd->obd_olg, LLOG_CONFIG_ORIG_CTXT, disk,
 679                         &llog_osd_ops);
 680         if (rc)
 681                 RETURN(rc);
 682
 683         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
 684         LASSERT(ctxt);
 685         ctxt->loc_dir = obd->u.cli.cl_mgc_configs_dir;
 686         llog_ctxt_put(ctxt);
 687
 688         RETURN(0);
 689 }
 690
 691 static int mgc_local_llog_fini(const struct lu_env *env,
 692                                struct obd_device *obd)
 693 {
 694         struct llog_ctxt *ctxt;
 695
 696         ENTRY;
 697
 698         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
 699         llog_cleanup(env, ctxt);
 700
 701         RETURN(0);
 702 }
 703
 704 static int mgc_fs_setup(struct obd_device *obd, struct super_block *sb)
 705 {
 706         struct lustre_sb_info   *lsi = s2lsi(sb);
 707         struct client_obd       *cli = &obd->u.cli;
 708         struct lu_fid            rfid, fid;
 709         struct dt_object        *root, *dto;
 710         struct lu_env           *env;
 711         int                      rc = 0;
 712
 713         ENTRY;
 714
 715         LASSERT(lsi);
 716         LASSERT(lsi->lsi_dt_dev);
 717
 718         OBD_ALLOC_PTR(env);
 719         if (env == NULL)
 720                 RETURN(-ENOMEM);
 721
 722         /* The mgc fs exclusion mutex. Only one fs can be setup at a time. */
 723         mutex_lock(&cli->cl_mgc_mutex);
 724
 725         /* Setup the configs dir */
 726         rc = lu_env_init(env, LCT_MG_THREAD);
 727         if (rc)
 728                 GOTO(out_err, rc);
 729
 730         fid.f_seq = FID_SEQ_LOCAL_NAME;
 731         fid.f_oid = 1;
 732         fid.f_ver = 0;
 733         rc = local_oid_storage_init(env, lsi->lsi_dt_dev, &fid,
 734                                     &cli->cl_mgc_los);
 735         if (rc)
 736                 GOTO(out_env, rc);
 737
 738         rc = dt_root_get(env, lsi->lsi_dt_dev, &rfid);
 739         if (rc)
 740                 GOTO(out_env, rc);
 741
 742         root = dt_locate_at(env, lsi->lsi_dt_dev, &rfid,
 743                             &cli->cl_mgc_los->los_dev->dd_lu_dev, NULL);
 744         if (unlikely(IS_ERR(root)))
 745                 GOTO(out_los, rc = PTR_ERR(root));
 746
 747         dto = local_file_find_or_create(env, cli->cl_mgc_los, root,
 748                                         MOUNT_CONFIGS_DIR,
 749                                         S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
 750         lu_object_put_nocache(env, &root->do_lu);
 751         if (IS_ERR(dto))
 752                 GOTO(out_los, rc = PTR_ERR(dto));
 753
 754         cli->cl_mgc_configs_dir = dto;
 755
 756         LASSERT(lsi->lsi_osd_exp->exp_obd->obd_lvfs_ctxt.dt);
 757         rc = mgc_local_llog_init(env, obd, lsi->lsi_osd_exp->exp_obd);
 758         if (rc)
 759                 GOTO(out_llog, rc);
 760
 761         /* We take an obd ref to insure that we can't get to mgc_cleanup
 762          * without calling mgc_fs_cleanup first. */
 763         class_incref(obd, "mgc_fs", obd);
 764
 765         /* We keep the cl_mgc_sem until mgc_fs_cleanup */
 766         EXIT;
 767 out_llog:
 768         if (rc) {
 769                 lu_object_put(env, &cli->cl_mgc_configs_dir->do_lu);
 770                 cli->cl_mgc_configs_dir = NULL;
 771         }
 772 out_los:
 773         if (rc < 0) {
 774                 local_oid_storage_fini(env, cli->cl_mgc_los);
 775                 cli->cl_mgc_los = NULL;
 776                 mutex_unlock(&cli->cl_mgc_mutex);
 777         }
 778 out_env:
 779         lu_env_fini(env);
 780 out_err:
 781         OBD_FREE_PTR(env);
 782         return rc;
 783 }
 784
 785 static int mgc_fs_cleanup(struct obd_device *obd)
 786 {
 787         struct lu_env            env;
 788         struct client_obd       *cli = &obd->u.cli;
 789         int                      rc;
 790
 791         ENTRY;
 792
 793         LASSERT(cli->cl_mgc_los != NULL);
 794
 795         rc = lu_env_init(&env, LCT_MG_THREAD);
 796         if (rc)
 797                 GOTO(unlock, rc);
 798
 799         mgc_local_llog_fini(&env, obd);
 800
 801         lu_object_put_nocache(&env, &cli->cl_mgc_configs_dir->do_lu);
 802         cli->cl_mgc_configs_dir = NULL;
 803
 804         local_oid_storage_fini(&env, cli->cl_mgc_los);
 805         cli->cl_mgc_los = NULL;
 806         lu_env_fini(&env);
 807
 808 unlock:
 809         class_decref(obd, "mgc_fs", obd);
 810         mutex_unlock(&cli->cl_mgc_mutex);
 811
 812         RETURN(0);
 813 }
 814
 815 static int mgc_llog_init(const struct lu_env *env, struct obd_device *obd)
 816 {
 817         struct llog_ctxt        *ctxt;
 818         int                      rc;
 819
 820         ENTRY;
 821
 822         /* setup only remote ctxt, the local disk context is switched per each
 823          * filesystem during mgc_fs_setup() */
 824         rc = llog_setup(env, obd, &obd->obd_olg, LLOG_CONFIG_REPL_CTXT, obd,
 825                         &llog_client_ops);
 826         if (rc)
 827                 RETURN(rc);
 828
 829         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
 830         LASSERT(ctxt);
 831
 832         llog_initiator_connect(ctxt);
 833         llog_ctxt_put(ctxt);
 834
 835         RETURN(0);
 836 }
 837
 838 static int mgc_llog_fini(const struct lu_env *env, struct obd_device *obd)
 839 {
 840         struct llog_ctxt *ctxt;
 841
 842         ENTRY;
 843
 844         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
 845         if (ctxt)
 846                 llog_cleanup(env, ctxt);
 847
 848         RETURN(0);
 849 }
 850
 851
 852 static atomic_t mgc_count = ATOMIC_INIT(0);
 853 static int mgc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 854 {
 855         int rc = 0;
 856         int temp;
 857         ENTRY;
 858
 859         switch (stage) {
 860         case OBD_CLEANUP_EARLY:
 861                 break;
 862         case OBD_CLEANUP_EXPORTS:
 863                 if (atomic_dec_and_test(&mgc_count)) {
 864                         LASSERT(rq_state & RQ_RUNNING);
 865                         /* stop requeue thread */
 866                         temp = RQ_STOP;
 867                 } else {
 868                         /* wakeup requeue thread to clean our cld */
 869                         temp = RQ_NOW | RQ_PRECLEANUP;
 870                 }
 871                 spin_lock(&config_list_lock);
 872                 rq_state |= temp;
 873                 spin_unlock(&config_list_lock);
 874                 wake_up(&rq_waitq);
 875                 if (temp & RQ_STOP)
 876                         wait_for_completion(&rq_exit);
 877                 obd_cleanup_client_import(obd);
 878                 rc = mgc_llog_fini(NULL, obd);
 879                 if (rc != 0)
 880                         CERROR("failed to cleanup llogging subsystems\n");
 881                 break;
 882         }
 883         RETURN(rc);
 884 }
 885
 886 static int mgc_cleanup(struct obd_device *obd)
 887 {
 888         int rc;
 889         ENTRY;
 890
 891         /* COMPAT_146 - old config logs may have added profiles we don't
 892            know about */
 893         if (obd->obd_type->typ_refcnt <= 1)
 894                 /* Only for the last mgc */
 895                 class_del_profiles();
 896
 897         lprocfs_obd_cleanup(obd);
 898         ptlrpcd_decref();
 899
 900         rc = client_obd_cleanup(obd);
 901         RETURN(rc);
 902 }
 903
 904 static int mgc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 905 {
 906         struct task_struct      *task;
 907         int                      rc;
 908         ENTRY;
 909
 910         rc = ptlrpcd_addref();
 911         if (rc < 0)
 912                 RETURN(rc);
 913
 914         rc = client_obd_setup(obd, lcfg);
 915         if (rc)
 916                 GOTO(err_decref, rc);
 917
 918         rc = mgc_llog_init(NULL, obd);
 919         if (rc) {
 920                 CERROR("failed to setup llogging subsystems\n");
 921                 GOTO(err_cleanup, rc);
 922         }
 923
 924 #ifdef LPROCFS
 925         obd->obd_vars = lprocfs_mgc_obd_vars;
 926         lprocfs_obd_setup(obd);
 927 #endif
 928         sptlrpc_lprocfs_cliobd_attach(obd);
 929
 930         if (atomic_inc_return(&mgc_count) == 1) {
 931                 rq_state = 0;
 932                 init_waitqueue_head(&rq_waitq);
 933
 934                 /* start requeue thread */
 935                 task = kthread_run(mgc_requeue_thread, NULL, "ll_cfg_requeue");
 936                 if (IS_ERR(task)) {
 937                         rc = PTR_ERR(task);
 938                         CERROR("%s: cannot start requeue thread: rc = %d; "
 939                                "no more log updates\n",
 940                                obd->obd_name, rc);
 941                         GOTO(err_cleanup, rc);
 942                 }
 943                 /* rc is the task_struct pointer of mgc_requeue_thread. */
 944                 rc = 0;
 945                 wait_for_completion(&rq_start);
 946         }
 947
 948         RETURN(rc);
 949
 950 err_cleanup:
 951         client_obd_cleanup(obd);
 952 err_decref:
 953         ptlrpcd_decref();
 954         RETURN(rc);
 955 }
 956
 957 /* based on ll_mdc_blocking_ast */
 958 static int mgc_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 959                             void *data, int flag)
 960 {
 961         struct lustre_handle lockh;
 962         struct config_llog_data *cld = (struct config_llog_data *)data;
 963         int rc = 0;
 964         ENTRY;
 965
 966         switch (flag) {
 967         case LDLM_CB_BLOCKING:
 968                 /* mgs wants the lock, give it up... */
 969                 LDLM_DEBUG(lock, "MGC blocking CB");
 970                 ldlm_lock2handle(lock, &lockh);
 971                 rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
 972                 break;
 973         case LDLM_CB_CANCELING:
 974                 /* We've given up the lock, prepare ourselves to update. */
 975                 LDLM_DEBUG(lock, "MGC cancel CB");
 976
 977                 CDEBUG(D_MGC, "Lock res "DLDLMRES" (%.8s)\n",
 978                        PLDLMRES(lock->l_resource),
 979                        (char *)&lock->l_resource->lr_name.name[0]);
 980
 981                 if (!cld) {
 982                         CDEBUG(D_INFO, "missing data, won't requeue\n");
 983                         break;
 984                 }
 985
 986                 /* held at mgc_process_log(). */
 987                 LASSERT(atomic_read(&cld->cld_refcount) > 0);
 988                 /* Are we done with this log? */
 989                 if (cld->cld_stopping) {
 990                         CDEBUG(D_MGC, "log %s: stopping, won't requeue\n",
 991                                 cld->cld_logname);
 992                         config_log_put(cld);
 993                         break;
 994                 }
 995                 /* Make sure not to re-enqueue when the mgc is stopping
 996                    (we get called from client_disconnect_export) */
 997                 if (!lock->l_conn_export ||
 998                     !lock->l_conn_export->exp_obd->u.cli.cl_conn_count) {
 999                         CDEBUG(D_MGC, "log %.8s: disconnecting, won't requeue\n",
1000                                 cld->cld_logname);
1001                         config_log_put(cld);
1002                         break;
1003                 }
1004
1005                 /* Re-enqueue now */
1006                 mgc_requeue_add(cld);
1007                 config_log_put(cld);
1008                 break;
1009         default:
1010                 LBUG();
1011         }
1012
1013         RETURN(rc);
1014 }
1015
1016 /* Not sure where this should go... */
1017 /* This is the timeout value for MGS_CONNECT request plus a ping interval, such
1018  * that we can have a chance to try the secondary MGS if any. */
1019 #define  MGC_ENQUEUE_LIMIT (INITIAL_CONNECT_TIMEOUT + (AT_OFF ? 0 : at_min) \
1020                                 + PING_INTERVAL)
1021 #define  MGC_TARGET_REG_LIMIT 10
1022 #define  MGC_SEND_PARAM_LIMIT 10
1023
1024 /* Send parameter to MGS*/
1025 static int mgc_set_mgs_param(struct obd_export *exp,
1026                              struct mgs_send_param *msp)
1027 {
1028         struct ptlrpc_request *req;
1029         struct mgs_send_param *req_msp, *rep_msp;
1030         int rc;
1031         ENTRY;
1032
1033         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1034                                         &RQF_MGS_SET_INFO, LUSTRE_MGS_VERSION,
1035                                         MGS_SET_INFO);
1036         if (!req)
1037                 RETURN(-ENOMEM);
1038
1039         req_msp = req_capsule_client_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
1040         if (!req_msp) {
1041                 ptlrpc_req_finished(req);
1042                 RETURN(-ENOMEM);
1043         }
1044
1045         memcpy(req_msp, msp, sizeof(*req_msp));
1046         ptlrpc_request_set_replen(req);
1047
1048         /* Limit how long we will wait for the enqueue to complete */
1049         req->rq_delay_limit = MGC_SEND_PARAM_LIMIT;
1050         rc = ptlrpc_queue_wait(req);
1051         if (!rc) {
1052                 rep_msp = req_capsule_server_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
1053                 memcpy(msp, rep_msp, sizeof(*rep_msp));
1054         }
1055
1056         ptlrpc_req_finished(req);
1057
1058         RETURN(rc);
1059 }
1060
1061 /* Take a config lock so we can get cancel notifications */
1062 static int mgc_enqueue(struct obd_export *exp, struct lov_stripe_md *lsm,
1063                        __u32 type, ldlm_policy_data_t *policy, __u32 mode,
1064                        __u64 *flags, void *bl_cb, void *cp_cb, void *gl_cb,
1065                        void *data, __u32 lvb_len, void *lvb_swabber,
1066                        struct lustre_handle *lockh)
1067 {
1068         struct config_llog_data *cld = (struct config_llog_data *)data;
1069         struct ldlm_enqueue_info einfo = {
1070                 .ei_type        = type,
1071                 .ei_mode        = mode,
1072                 .ei_cb_bl       = mgc_blocking_ast,
1073                 .ei_cb_cp       = ldlm_completion_ast,
1074         };
1075         struct ptlrpc_request *req;
1076         int short_limit = cld_is_sptlrpc(cld);
1077         int rc;
1078         ENTRY;
1079
1080         CDEBUG(D_MGC, "Enqueue for %s (res "LPX64")\n", cld->cld_logname,
1081                cld->cld_resid.name[0]);
1082
1083         /* We need a callback for every lockholder, so don't try to
1084            ldlm_lock_match (see rev 1.1.2.11.2.47) */
1085         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1086                                         &RQF_LDLM_ENQUEUE, LUSTRE_DLM_VERSION,
1087                                         LDLM_ENQUEUE);
1088         if (req == NULL)
1089                 RETURN(-ENOMEM);
1090
1091         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER, 0);
1092         ptlrpc_request_set_replen(req);
1093
1094         /* check if this is server or client */
1095         if (cld->cld_cfg.cfg_sb) {
1096                 struct lustre_sb_info *lsi = s2lsi(cld->cld_cfg.cfg_sb);
1097                 if (lsi && IS_SERVER(lsi))
1098                         short_limit = 1;
1099         }
1100         /* Limit how long we will wait for the enqueue to complete */
1101         req->rq_delay_limit = short_limit ? 5 : MGC_ENQUEUE_LIMIT;
1102         rc = ldlm_cli_enqueue(exp, &req, &einfo, &cld->cld_resid, NULL, flags,
1103                               NULL, 0, LVB_T_NONE, lockh, 0);
1104         /* A failed enqueue should still call the mgc_blocking_ast,
1105            where it will be requeued if needed ("grant failed"). */
1106         ptlrpc_req_finished(req);
1107         RETURN(rc);
1108 }
1109
1110 static int mgc_cancel(struct obd_export *exp, ldlm_mode_t mode,
1111                       struct lustre_handle *lockh)
1112 {
1113         ENTRY;
1114
1115         ldlm_lock_decref(lockh, mode);
1116
1117         RETURN(0);
1118 }
1119
1120 static void mgc_notify_active(struct obd_device *unused)
1121 {
1122         /* wakeup mgc_requeue_thread to requeue mgc lock */
1123         spin_lock(&config_list_lock);
1124         rq_state |= RQ_NOW;
1125         spin_unlock(&config_list_lock);
1126         wake_up(&rq_waitq);
1127
1128         /* TODO: Help the MGS rebuild nidtbl. -jay */
1129 }
1130
1131 /* Send target_reg message to MGS */
1132 static int mgc_target_register(struct obd_export *exp,
1133                                struct mgs_target_info *mti)
1134 {
1135         struct ptlrpc_request  *req;
1136         struct mgs_target_info *req_mti, *rep_mti;
1137         int                     rc;
1138         ENTRY;
1139
1140         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
1141                                         &RQF_MGS_TARGET_REG, LUSTRE_MGS_VERSION,
1142                                         MGS_TARGET_REG);
1143         if (req == NULL)
1144                 RETURN(-ENOMEM);
1145
1146         req_mti = req_capsule_client_get(&req->rq_pill, &RMF_MGS_TARGET_INFO);
1147         if (!req_mti) {
1148                 ptlrpc_req_finished(req);
1149                 RETURN(-ENOMEM);
1150         }
1151
1152         memcpy(req_mti, mti, sizeof(*req_mti));
1153         ptlrpc_request_set_replen(req);
1154         CDEBUG(D_MGC, "register %s\n", mti->mti_svname);
1155         /* Limit how long we will wait for the enqueue to complete */
1156         req->rq_delay_limit = MGC_TARGET_REG_LIMIT;
1157
1158         rc = ptlrpc_queue_wait(req);
1159         if (!rc) {
1160                 rep_mti = req_capsule_server_get(&req->rq_pill,
1161                                                  &RMF_MGS_TARGET_INFO);
1162                 memcpy(mti, rep_mti, sizeof(*rep_mti));
1163                 CDEBUG(D_MGC, "register %s got index = %d\n",
1164                        mti->mti_svname, mti->mti_stripe_index);
1165         }
1166         ptlrpc_req_finished(req);
1167
1168         RETURN(rc);
1169 }
1170
1171 int mgc_set_info_async(const struct lu_env *env, struct obd_export *exp,
1172                        obd_count keylen, void *key, obd_count vallen,
1173                        void *val, struct ptlrpc_request_set *set)
1174 {
1175         int rc = -EINVAL;
1176         ENTRY;
1177
1178         /* Turn off initial_recov after we try all backup servers once */
1179         if (KEY_IS(KEY_INIT_RECOV_BACKUP)) {
1180                 struct obd_import *imp = class_exp2cliimp(exp);
1181                 int value;
1182                 if (vallen != sizeof(int))
1183                         RETURN(-EINVAL);
1184                 value = *(int *)val;
1185                 CDEBUG(D_MGC, "InitRecov %s %d/d%d:i%d:r%d:or%d:%s\n",
1186                        imp->imp_obd->obd_name, value,
1187                        imp->imp_deactive, imp->imp_invalid,
1188                        imp->imp_replayable, imp->imp_obd->obd_replayable,
1189                        ptlrpc_import_state_name(imp->imp_state));
1190                 /* Resurrect if we previously died */
1191                 if ((imp->imp_state != LUSTRE_IMP_FULL &&
1192                      imp->imp_state != LUSTRE_IMP_NEW) || value > 1)
1193                         ptlrpc_reconnect_import(imp);
1194                 RETURN(0);
1195         }
1196         /* FIXME move this to mgc_process_config */
1197         if (KEY_IS(KEY_REGISTER_TARGET)) {
1198                 struct mgs_target_info *mti;
1199                 if (vallen != sizeof(struct mgs_target_info))
1200                         RETURN(-EINVAL);
1201                 mti = (struct mgs_target_info *)val;
1202                 CDEBUG(D_MGC, "register_target %s %#x\n",
1203                        mti->mti_svname, mti->mti_flags);
1204                 rc =  mgc_target_register(exp, mti);
1205                 RETURN(rc);
1206         }
1207         if (KEY_IS(KEY_SET_FS)) {
1208                 struct super_block *sb = (struct super_block *)val;
1209
1210                 if (vallen != sizeof(struct super_block))
1211                         RETURN(-EINVAL);
1212
1213                 rc = mgc_fs_setup(exp->exp_obd, sb);
1214                 RETURN(rc);
1215         }
1216         if (KEY_IS(KEY_CLEAR_FS)) {
1217                 if (vallen != 0)
1218                         RETURN(-EINVAL);
1219                 rc = mgc_fs_cleanup(exp->exp_obd);
1220                 RETURN(rc);
1221         }
1222         if (KEY_IS(KEY_SET_INFO)) {
1223                 struct mgs_send_param *msp;
1224
1225                 msp = (struct mgs_send_param *)val;
1226                 rc =  mgc_set_mgs_param(exp, msp);
1227                 RETURN(rc);
1228         }
1229         if (KEY_IS(KEY_MGSSEC)) {
1230                 struct client_obd     *cli = &exp->exp_obd->u.cli;
1231                 struct sptlrpc_flavor  flvr;
1232
1233                 /*
1234                  * empty string means using current flavor, if which haven't
1235                  * been set yet, set it as null.
1236                  *
1237                  * if flavor has been set previously, check the asking flavor
1238                  * must match the existing one.
1239                  */
1240                 if (vallen == 0) {
1241                         if (cli->cl_flvr_mgc.sf_rpc != SPTLRPC_FLVR_INVALID)
1242                                 RETURN(0);
1243                         val = "null";
1244                         vallen = 4;
1245                 }
1246
1247                 rc = sptlrpc_parse_flavor(val, &flvr);
1248                 if (rc) {
1249                         CERROR("invalid sptlrpc flavor %s to MGS\n",
1250                                (char *) val);
1251                         RETURN(rc);
1252                 }
1253
1254                 /*
1255                  * caller already hold a mutex
1256                  */
1257                 if (cli->cl_flvr_mgc.sf_rpc == SPTLRPC_FLVR_INVALID) {
1258                         cli->cl_flvr_mgc = flvr;
1259                 } else if (memcmp(&cli->cl_flvr_mgc, &flvr,
1260                                   sizeof(flvr)) != 0) {
1261                         char    str[20];
1262
1263                         sptlrpc_flavor2name(&cli->cl_flvr_mgc,
1264                                             str, sizeof(str));
1265                         LCONSOLE_ERROR("asking sptlrpc flavor %s to MGS but "
1266                                        "currently %s is in use\n",
1267                                        (char *) val, str);
1268                         rc = -EPERM;
1269                 }
1270                 RETURN(rc);
1271         }
1272
1273         RETURN(rc);
1274 }
1275
1276 static int mgc_get_info(const struct lu_env *env, struct obd_export *exp,
1277                         __u32 keylen, void *key, __u32 *vallen, void *val,
1278                         struct lov_stripe_md *unused)
1279 {
1280         int rc = -EINVAL;
1281
1282         if (KEY_IS(KEY_CONN_DATA)) {
1283                 struct obd_import *imp = class_exp2cliimp(exp);
1284                 struct obd_connect_data *data = val;
1285
1286                 if (*vallen == sizeof(*data)) {
1287                         *data = imp->imp_connect_data;
1288                         rc = 0;
1289                 }
1290         }
1291
1292         return rc;
1293 }
1294
1295 static int mgc_import_event(struct obd_device *obd,
1296                             struct obd_import *imp,
1297                             enum obd_import_event event)
1298 {
1299         int rc = 0;
1300
1301         LASSERT(imp->imp_obd == obd);
1302         CDEBUG(D_MGC, "import event %#x\n", event);
1303
1304         switch (event) {
1305         case IMP_EVENT_DISCON:
1306                 /* MGC imports should not wait for recovery */
1307                 if (OCD_HAS_FLAG(&imp->imp_connect_data, IMP_RECOV))
1308                         ptlrpc_pinger_ir_down();
1309                 break;
1310         case IMP_EVENT_INACTIVE:
1311                 break;
1312         case IMP_EVENT_INVALIDATE: {
1313                 struct ldlm_namespace *ns = obd->obd_namespace;
1314                 ldlm_namespace_cleanup(ns, LDLM_FL_LOCAL_ONLY);
1315                 break;
1316         }
1317         case IMP_EVENT_ACTIVE:
1318                 CDEBUG(D_INFO, "%s: Reactivating import\n", obd->obd_name);
1319                 /* Clearing obd_no_recov allows us to continue pinging */
1320                 obd->obd_no_recov = 0;
1321                 mgc_notify_active(obd);
1322                 if (OCD_HAS_FLAG(&imp->imp_connect_data, IMP_RECOV))
1323                         ptlrpc_pinger_ir_up();
1324                 break;
1325         case IMP_EVENT_OCD:
1326                 break;
1327         case IMP_EVENT_DEACTIVATE:
1328         case IMP_EVENT_ACTIVATE:
1329                 break;
1330         default:
1331                 CERROR("Unknown import event %#x\n", event);
1332                 LBUG();
1333         }
1334         RETURN(rc);
1335 }
1336
1337 enum {
1338         CONFIG_READ_NRPAGES_INIT = 1 << (20 - PAGE_CACHE_SHIFT),
1339         CONFIG_READ_NRPAGES      = 4
1340 };
1341
1342 static int mgc_apply_recover_logs(struct obd_device *mgc,
1343                                   struct config_llog_data *cld,
1344                                   __u64 max_version,
1345                                   void *data, int datalen, bool mne_swab)
1346 {
1347         struct config_llog_instance *cfg = &cld->cld_cfg;
1348         struct lustre_sb_info       *lsi = s2lsi(cfg->cfg_sb);
1349         struct mgs_nidtbl_entry *entry;
1350         struct lustre_cfg       *lcfg;
1351         struct lustre_cfg_bufs   bufs;
1352         u64   prev_version = 0;
1353         char *inst;
1354         char *buf;
1355         int   bufsz;
1356         int   pos;
1357         int   rc  = 0;
1358         int   off = 0;
1359         ENTRY;
1360
1361         LASSERT(cfg->cfg_instance != NULL);
1362         LASSERT(cfg->cfg_sb == cfg->cfg_instance);
1363
1364         OBD_ALLOC(inst, PAGE_CACHE_SIZE);
1365         if (inst == NULL)
1366                 RETURN(-ENOMEM);
1367
1368         if (!IS_SERVER(lsi)) {
1369                 pos = snprintf(inst, PAGE_CACHE_SIZE, "%p", cfg->cfg_instance);
1370                 if (pos >= PAGE_CACHE_SIZE) {
1371                         OBD_FREE(inst, PAGE_CACHE_SIZE);
1372                         return -E2BIG;
1373                 }
1374         } else {
1375                 LASSERT(IS_MDT(lsi));
1376                 rc = server_name2svname(lsi->lsi_svname, inst, NULL,
1377                                         PAGE_CACHE_SIZE);
1378                 if (rc) {
1379                         OBD_FREE(inst, PAGE_CACHE_SIZE);
1380                         RETURN(-EINVAL);
1381                 }
1382                 pos = strlen(inst);
1383         }
1384
1385         ++pos;
1386         buf   = inst + pos;
1387         bufsz = PAGE_CACHE_SIZE - pos;
1388
1389         while (datalen > 0) {
1390                 int   entry_len = sizeof(*entry);
1391                 int   is_ost;
1392                 struct obd_device *obd;
1393                 char *obdname;
1394                 char *cname;
1395                 char *params;
1396                 char *uuid;
1397
1398                 rc = -EINVAL;
1399                 if (datalen < sizeof(*entry))
1400                         break;
1401
1402                 entry = (typeof(entry))(data + off);
1403
1404                 /* sanity check */
1405                 if (entry->mne_nid_type != 0) /* only support type 0 for ipv4 */
1406                         break;
1407                 if (entry->mne_nid_count == 0) /* at least one nid entry */
1408                         break;
1409                 if (entry->mne_nid_size != sizeof(lnet_nid_t))
1410                         break;
1411
1412                 entry_len += entry->mne_nid_count * entry->mne_nid_size;
1413                 if (datalen < entry_len) /* must have entry_len at least */
1414                         break;
1415
1416                 /* Keep this swab for normal mixed endian handling. LU-1644 */
1417                 if (mne_swab)
1418                         lustre_swab_mgs_nidtbl_entry(entry);
1419                 if (entry->mne_length > PAGE_CACHE_SIZE) {
1420                         CERROR("MNE too large (%u)\n", entry->mne_length);
1421                         break;
1422                 }
1423
1424                 if (entry->mne_length < entry_len)
1425                         break;
1426
1427                 off     += entry->mne_length;
1428                 datalen -= entry->mne_length;
1429                 if (datalen < 0)
1430                         break;
1431
1432                 if (entry->mne_version > max_version) {
1433                         CERROR("entry index(%lld) is over max_index(%lld)\n",
1434                                entry->mne_version, max_version);
1435                         break;
1436                 }
1437
1438                 if (prev_version >= entry->mne_version) {
1439                         CERROR("index unsorted, prev %lld, now %lld\n",
1440                                prev_version, entry->mne_version);
1441                         break;
1442                 }
1443                 prev_version = entry->mne_version;
1444
1445                 /*
1446                  * Write a string with format "nid::instance" to
1447                  * lustre/<osc|mdc>/<target>-<osc|mdc>-<instance>/import.
1448                  */
1449
1450                 is_ost = entry->mne_type == LDD_F_SV_TYPE_OST;
1451                 memset(buf, 0, bufsz);
1452                 obdname = buf;
1453                 pos = 0;
1454
1455                 /* lustre-OST0001-osc-<instance #> */
1456                 strcpy(obdname, cld->cld_logname);
1457                 cname = strrchr(obdname, '-');
1458                 if (cname == NULL) {
1459                         CERROR("mgc %s: invalid logname %s\n",
1460                                mgc->obd_name, obdname);
1461                         break;
1462                 }
1463
1464                 pos = cname - obdname;
1465                 obdname[pos] = 0;
1466                 pos += sprintf(obdname + pos, "-%s%04x",
1467                                   is_ost ? "OST" : "MDT", entry->mne_index);
1468
1469                 cname = is_ost ? "osc" : "mdc",
1470                 pos += sprintf(obdname + pos, "-%s-%s", cname, inst);
1471                 lustre_cfg_bufs_reset(&bufs, obdname);
1472
1473                 /* find the obd by obdname */
1474                 obd = class_name2obd(obdname);
1475                 if (obd == NULL) {
1476                         CDEBUG(D_INFO, "mgc %s: cannot find obdname %s\n",
1477                                mgc->obd_name, obdname);
1478                         rc = 0;
1479                         /* this is a safe race, when the ost is starting up...*/
1480                         continue;
1481                 }
1482
1483                 /* osc.import = "connection=<Conn UUID>::<target instance>" */
1484                 ++pos;
1485                 params = buf + pos;
1486                 pos += sprintf(params, "%s.import=%s", cname, "connection=");
1487                 uuid = buf + pos;
1488
1489                 down_read(&obd->u.cli.cl_sem);
1490                 if (obd->u.cli.cl_import == NULL) {
1491                         /* client does not connect to the OST yet */
1492                         up_read(&obd->u.cli.cl_sem);
1493                         rc = 0;
1494                         continue;
1495                 }
1496
1497                 /* TODO: iterate all nids to find one */
1498                 /* find uuid by nid */
1499                 rc = client_import_find_conn(obd->u.cli.cl_import,
1500                                              entry->u.nids[0],
1501                                              (struct obd_uuid *)uuid);
1502                 up_read(&obd->u.cli.cl_sem);
1503                 if (rc < 0) {
1504                         CERROR("mgc: cannot find uuid by nid %s\n",
1505                                libcfs_nid2str(entry->u.nids[0]));
1506                         break;
1507                 }
1508
1509                 CDEBUG(D_INFO, "Find uuid %s by nid %s\n",
1510                        uuid, libcfs_nid2str(entry->u.nids[0]));
1511
1512                 pos += strlen(uuid);
1513                 pos += sprintf(buf + pos, "::%u", entry->mne_instance);
1514                 LASSERT(pos < bufsz);
1515
1516                 lustre_cfg_bufs_set_string(&bufs, 1, params);
1517
1518                 rc = -ENOMEM;
1519                 lcfg = lustre_cfg_new(LCFG_PARAM, &bufs);
1520                 if (lcfg == NULL) {
1521                         CERROR("mgc: cannot allocate memory\n");
1522                         break;
1523                 }
1524
1525                 CDEBUG(D_INFO, "ir apply logs "LPD64"/"LPD64" for %s -> %s\n",
1526                        prev_version, max_version, obdname, params);
1527
1528                 rc = class_process_config(lcfg);
1529                 lustre_cfg_free(lcfg);
1530                 if (rc)
1531                         CDEBUG(D_INFO, "process config for %s error %d\n",
1532                                obdname, rc);
1533
1534                 /* continue, even one with error */
1535         }
1536
1537         OBD_FREE(inst, PAGE_CACHE_SIZE);
1538         RETURN(rc);
1539 }
1540
1541 /**
1542  * This function is called if this client was notified for target restarting
1543  * by the MGS. A CONFIG_READ RPC is going to send to fetch recovery logs.
1544  */
1545 static int mgc_process_recover_log(struct obd_device *obd,
1546                                    struct config_llog_data *cld)
1547 {
1548         struct ptlrpc_request *req = NULL;
1549         struct config_llog_instance *cfg = &cld->cld_cfg;
1550         struct mgs_config_body *body;
1551         struct mgs_config_res  *res;
1552         struct ptlrpc_bulk_desc *desc;
1553         struct page **pages;
1554         int nrpages;
1555         bool eof = true;
1556         bool mne_swab = false;
1557         int i;
1558         int ealen;
1559         int rc;
1560         ENTRY;
1561
1562         /* allocate buffer for bulk transfer.
1563          * if this is the first time for this mgs to read logs,
1564          * CONFIG_READ_NRPAGES_INIT will be used since it will read all logs
1565          * once; otherwise, it only reads increment of logs, this should be
1566          * small and CONFIG_READ_NRPAGES will be used.
1567          */
1568         nrpages = CONFIG_READ_NRPAGES;
1569         if (cfg->cfg_last_idx == 0) /* the first time */
1570                 nrpages = CONFIG_READ_NRPAGES_INIT;
1571
1572         OBD_ALLOC(pages, sizeof(*pages) * nrpages);
1573         if (pages == NULL)
1574                 GOTO(out, rc = -ENOMEM);
1575
1576         for (i = 0; i < nrpages; i++) {
1577                 pages[i] = alloc_page(GFP_IOFS);
1578                 if (pages[i] == NULL)
1579                         GOTO(out, rc = -ENOMEM);
1580         }
1581
1582 again:
1583         LASSERT(cld_is_recover(cld));
1584         LASSERT(mutex_is_locked(&cld->cld_lock));
1585         req = ptlrpc_request_alloc(class_exp2cliimp(cld->cld_mgcexp),
1586                                    &RQF_MGS_CONFIG_READ);
1587         if (req == NULL)
1588                 GOTO(out, rc = -ENOMEM);
1589
1590         rc = ptlrpc_request_pack(req, LUSTRE_MGS_VERSION, MGS_CONFIG_READ);
1591         if (rc)
1592                 GOTO(out, rc);
1593
1594         /* pack request */
1595         body = req_capsule_client_get(&req->rq_pill, &RMF_MGS_CONFIG_BODY);
1596         LASSERT(body != NULL);
1597         LASSERT(sizeof(body->mcb_name) > strlen(cld->cld_logname));
1598         if (strlcpy(body->mcb_name, cld->cld_logname, sizeof(body->mcb_name))
1599             >= sizeof(body->mcb_name))
1600                 GOTO(out, rc = -E2BIG);
1601         body->mcb_offset = cfg->cfg_last_idx + 1;
1602         body->mcb_type   = cld->cld_type;
1603         body->mcb_bits   = PAGE_CACHE_SHIFT;
1604         body->mcb_units  = nrpages;
1605
1606         /* allocate bulk transfer descriptor */
1607         desc = ptlrpc_prep_bulk_imp(req, nrpages, 1, BULK_PUT_SINK,
1608                                     MGS_BULK_PORTAL);
1609         if (desc == NULL)
1610                 GOTO(out, rc = -ENOMEM);
1611
1612         for (i = 0; i < nrpages; i++)
1613                 ptlrpc_prep_bulk_page_pin(desc, pages[i], 0, PAGE_CACHE_SIZE);
1614
1615         ptlrpc_request_set_replen(req);
1616         rc = ptlrpc_queue_wait(req);
1617         if (rc)
1618                 GOTO(out, rc);
1619
1620         res = req_capsule_server_get(&req->rq_pill, &RMF_MGS_CONFIG_RES);
1621         if (res->mcr_size < res->mcr_offset)
1622                 GOTO(out, rc = -EINVAL);
1623
1624         /* always update the index even though it might have errors with
1625          * handling the recover logs */
1626         cfg->cfg_last_idx = res->mcr_offset;
1627         eof = res->mcr_offset == res->mcr_size;
1628
1629         CDEBUG(D_INFO, "Latest version "LPD64", more %d.\n",
1630                res->mcr_offset, eof == false);
1631
1632         ealen = sptlrpc_cli_unwrap_bulk_read(req, req->rq_bulk, 0);
1633         if (ealen < 0)
1634                 GOTO(out, rc = ealen);
1635
1636         if (ealen > nrpages << PAGE_CACHE_SHIFT)
1637                 GOTO(out, rc = -EINVAL);
1638
1639         if (ealen == 0) { /* no logs transferred */
1640                 if (!eof)
1641                         rc = -EINVAL;
1642                 GOTO(out, rc);
1643         }
1644
1645         mne_swab = !!ptlrpc_rep_need_swab(req);
1646 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 0, 53, 0)
1647         /* This import flag means the server did an extra swab of IR MNE
1648          * records (fixed in LU-1252), reverse it here if needed. LU-1644 */
1649         if (unlikely(req->rq_import->imp_need_mne_swab))
1650                 mne_swab = !mne_swab;
1651 #endif
1652
1653         for (i = 0; i < nrpages && ealen > 0; i++) {
1654                 int rc2;
1655                 void *ptr;
1656
1657                 ptr = kmap(pages[i]);
1658                 rc2 = mgc_apply_recover_logs(obd, cld, res->mcr_offset, ptr,
1659                                              min_t(int, ealen, PAGE_CACHE_SIZE),
1660                                              mne_swab);
1661                 kunmap(pages[i]);
1662                 if (rc2 < 0) {
1663                         CWARN("Process recover log %s error %d\n",
1664                               cld->cld_logname, rc2);
1665                         break;
1666                 }
1667
1668                 ealen -= PAGE_CACHE_SIZE;
1669         }
1670
1671 out:
1672         if (req)
1673                 ptlrpc_req_finished(req);
1674
1675         if (rc == 0 && !eof)
1676                 goto again;
1677
1678         if (pages) {
1679                 for (i = 0; i < nrpages; i++) {
1680                         if (pages[i] == NULL)
1681                                 break;
1682                         __free_page(pages[i]);
1683                 }
1684                 OBD_FREE(pages, sizeof(*pages) * nrpages);
1685         }
1686         return rc;
1687 }
1688
1689 /* Copy a remote log locally */
1690 static int mgc_llog_local_copy(const struct lu_env *env,
1691                                struct obd_device *obd,
1692                                struct llog_ctxt *rctxt,
1693                                struct llog_ctxt *lctxt, char *logname)
1694 {
1695         char    *temp_log;
1696         int      rc;
1697
1698         ENTRY;
1699
1700         /*
1701          * - copy it to backup using llog_backup()
1702          * - copy remote llog to logname using llog_backup()
1703          * - if failed then move bakup to logname again
1704          */
1705
1706         OBD_ALLOC(temp_log, strlen(logname) + 1);
1707         if (!temp_log)
1708                 RETURN(-ENOMEM);
1709         sprintf(temp_log, "%sT", logname);
1710
1711         /* make a copy of local llog at first */
1712         rc = llog_backup(env, obd, lctxt, lctxt, logname, temp_log);
1713         if (rc < 0 && rc != -ENOENT)
1714                 GOTO(out, rc);
1715         /* copy remote llog to the local copy */
1716         rc = llog_backup(env, obd, rctxt, lctxt, logname, logname);
1717         if (rc == -ENOENT) {
1718                 /* no remote llog, delete local one too */
1719                 llog_erase(env, lctxt, NULL, logname);
1720         } else if (rc < 0) {
1721                 /* error during backup, get local one back from the copy */
1722                 llog_backup(env, obd, lctxt, lctxt, temp_log, logname);
1723 out:
1724                 CERROR("%s: failed to copy remote log %s: rc = %d\n",
1725                        obd->obd_name, logname, rc);
1726         }
1727         llog_erase(env, lctxt, NULL, temp_log);
1728         OBD_FREE(temp_log, strlen(logname) + 1);
1729         return rc;
1730 }
1731
1732 /* local_only means it cannot get remote llogs */
1733 static int mgc_process_cfg_log(struct obd_device *mgc,
1734                                struct config_llog_data *cld, int local_only)
1735 {
1736         struct llog_ctxt        *ctxt, *lctxt = NULL;
1737         struct client_obd       *cli = &mgc->u.cli;
1738         struct lustre_sb_info   *lsi = NULL;
1739         int                      rc = 0;
1740         bool                     sptlrpc_started = false;
1741         struct lu_env           *env;
1742
1743         ENTRY;
1744
1745         LASSERT(cld);
1746         LASSERT(mutex_is_locked(&cld->cld_lock));
1747
1748         /*
1749          * local copy of sptlrpc log is controlled elsewhere, don't try to
1750          * read it up here.
1751          */
1752         if (cld_is_sptlrpc(cld) && local_only)
1753                 RETURN(0);
1754
1755         if (cld->cld_cfg.cfg_sb)
1756                 lsi = s2lsi(cld->cld_cfg.cfg_sb);
1757
1758         OBD_ALLOC_PTR(env);
1759         if (env == NULL)
1760                 RETURN(-ENOMEM);
1761
1762         rc = lu_env_init(env, LCT_MG_THREAD);
1763         if (rc)
1764                 GOTO(out_free, rc);
1765
1766         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
1767         LASSERT(ctxt);
1768
1769         lctxt = llog_get_context(mgc, LLOG_CONFIG_ORIG_CTXT);
1770
1771         /* Copy the setup log locally if we can. Don't mess around if we're
1772          * running an MGS though (logs are already local). */
1773         if (lctxt && lsi && IS_SERVER(lsi) && !IS_MGS(lsi) &&
1774             cli->cl_mgc_configs_dir != NULL &&
1775             lu2dt_dev(cli->cl_mgc_configs_dir->do_lu.lo_dev) ==
1776             lsi->lsi_dt_dev) {
1777                 if (!local_only)
1778                         /* Only try to copy log if we have the lock. */
1779                         rc = mgc_llog_local_copy(env, mgc, ctxt, lctxt,
1780                                                  cld->cld_logname);
1781                 if (local_only || rc) {
1782                         if (strcmp(cld->cld_logname, PARAMS_FILENAME) != 0 &&
1783                             llog_is_empty(env, lctxt, cld->cld_logname)) {
1784                                 LCONSOLE_ERROR_MSG(0x13a, "Failed to get MGS "
1785                                                    "log %s and no local copy."
1786                                                    "\n", cld->cld_logname);
1787                                 GOTO(out_pop, rc = -ENOENT);
1788                         }
1789                         CDEBUG(D_MGC, "Failed to get MGS log %s, using local "
1790                                "copy for now, will try to update later.\n",
1791                                cld->cld_logname);
1792                         rc = 0;
1793                 }
1794                 /* Now, whether we copied or not, start using the local llog.
1795                  * If we failed to copy, we'll start using whatever the old
1796                  * log has. */
1797                 llog_ctxt_put(ctxt);
1798                 ctxt = lctxt;
1799                 lctxt = NULL;
1800         } else {
1801                 if (local_only) /* no local log at client side */
1802                         GOTO(out_pop, rc = -EIO);
1803         }
1804
1805         if (cld_is_sptlrpc(cld)) {
1806                 sptlrpc_conf_log_update_begin(cld->cld_logname);
1807                 sptlrpc_started = true;
1808         }
1809
1810         /* logname and instance info should be the same, so use our
1811          * copy of the instance for the update.  The cfg_last_idx will
1812          * be updated here. */
1813         rc = class_config_parse_llog(env, ctxt, cld->cld_logname,
1814                                      &cld->cld_cfg);
1815         EXIT;
1816
1817 out_pop:
1818         __llog_ctxt_put(env, ctxt);
1819         if (lctxt)
1820                 __llog_ctxt_put(env, lctxt);
1821
1822         /*
1823          * update settings on existing OBDs. doing it inside
1824          * of llog_process_lock so no device is attaching/detaching
1825          * in parallel.
1826          * the logname must be <fsname>-sptlrpc
1827          */
1828         if (sptlrpc_started) {
1829                 LASSERT(cld_is_sptlrpc(cld));
1830                 sptlrpc_conf_log_update_end(cld->cld_logname);
1831                 class_notify_sptlrpc_conf(cld->cld_logname,
1832                                           strlen(cld->cld_logname) -
1833                                           strlen("-sptlrpc"));
1834         }
1835
1836         lu_env_fini(env);
1837 out_free:
1838         OBD_FREE_PTR(env);
1839         return rc;
1840 }
1841
1842 /** Get a config log from the MGS and process it.
1843  * This func is called for both clients and servers.
1844  * Copy the log locally before parsing it if appropriate (non-MGS server)
1845  */
1846 int mgc_process_log(struct obd_device *mgc, struct config_llog_data *cld)
1847 {
1848         struct lustre_handle lockh = { 0 };
1849         __u64 flags = LDLM_FL_NO_LRU;
1850         int rc = 0, rcl;
1851         ENTRY;
1852
1853         LASSERT(cld);
1854
1855         /* I don't want multiple processes running process_log at once --
1856            sounds like badness.  It actually might be fine, as long as
1857            we're not trying to update from the same log
1858            simultaneously (in which case we should use a per-log sem.) */
1859         mutex_lock(&cld->cld_lock);
1860         if (cld->cld_stopping) {
1861                 mutex_unlock(&cld->cld_lock);
1862                 RETURN(0);
1863         }
1864
1865         OBD_FAIL_TIMEOUT(OBD_FAIL_MGC_PAUSE_PROCESS_LOG, 20);
1866
1867         CDEBUG(D_MGC, "Process log %s:%p from %d\n", cld->cld_logname,
1868                cld->cld_cfg.cfg_instance, cld->cld_cfg.cfg_last_idx + 1);
1869
1870         /* Get the cfg lock on the llog */
1871         rcl = mgc_enqueue(mgc->u.cli.cl_mgc_mgsexp, NULL, LDLM_PLAIN, NULL,
1872                           LCK_CR, &flags, NULL, NULL, NULL,
1873                           cld, 0, NULL, &lockh);
1874         if (rcl == 0) {
1875                 /* Get the cld, it will be released in mgc_blocking_ast. */
1876                 config_log_get(cld);
1877                 rc = ldlm_lock_set_data(&lockh, (void *)cld);
1878                 LASSERT(rc == 0);
1879         } else {
1880                 CDEBUG(D_MGC, "Can't get cfg lock: %d\n", rcl);
1881
1882                 /* mark cld_lostlock so that it will requeue
1883                  * after MGC becomes available. */
1884                 cld->cld_lostlock = 1;
1885                 /* Get extra reference, it will be put in requeue thread */
1886                 config_log_get(cld);
1887         }
1888
1889
1890         if (cld_is_recover(cld)) {
1891                 rc = 0; /* this is not a fatal error for recover log */
1892                 if (rcl == 0)
1893                         rc = mgc_process_recover_log(mgc, cld);
1894         } else {
1895                 rc = mgc_process_cfg_log(mgc, cld, rcl != 0);
1896         }
1897
1898         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
1899                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
1900
1901         mutex_unlock(&cld->cld_lock);
1902
1903         /* Now drop the lock so MGS can revoke it */
1904         if (!rcl) {
1905                 rcl = mgc_cancel(mgc->u.cli.cl_mgc_mgsexp, LCK_CR, &lockh);
1906                 if (rcl)
1907                         CERROR("Can't drop cfg lock: %d\n", rcl);
1908         }
1909
1910         RETURN(rc);
1911 }
1912
1913
1914 /** Called from lustre_process_log.
1915  * LCFG_LOG_START gets the config log from the MGS, processes it to start
1916  * any services, and adds it to the list logs to watch (follow).
1917  */
1918 static int mgc_process_config(struct obd_device *obd, obd_count len, void *buf)
1919 {
1920         struct lustre_cfg *lcfg = buf;
1921         struct config_llog_instance *cfg = NULL;
1922         char *logname;
1923         int rc = 0;
1924         ENTRY;
1925
1926         switch(lcfg->lcfg_command) {
1927         case LCFG_LOV_ADD_OBD: {
1928                 /* Overloading this cfg command: register a new target */
1929                 struct mgs_target_info *mti;
1930
1931                 if (LUSTRE_CFG_BUFLEN(lcfg, 1) !=
1932                     sizeof(struct mgs_target_info))
1933                         GOTO(out, rc = -EINVAL);
1934
1935                 mti = (struct mgs_target_info *)lustre_cfg_buf(lcfg, 1);
1936                 CDEBUG(D_MGC, "add_target %s %#x\n",
1937                        mti->mti_svname, mti->mti_flags);
1938                 rc = mgc_target_register(obd->u.cli.cl_mgc_mgsexp, mti);
1939                 break;
1940         }
1941         case LCFG_LOV_DEL_OBD:
1942                 /* Unregister has no meaning at the moment. */
1943                 CERROR("lov_del_obd unimplemented\n");
1944                 rc = -ENOSYS;
1945                 break;
1946         case LCFG_SPTLRPC_CONF: {
1947                 rc = sptlrpc_process_config(lcfg);
1948                 break;
1949         }
1950         case LCFG_LOG_START: {
1951                 struct config_llog_data *cld;
1952                 struct super_block *sb;
1953
1954                 logname = lustre_cfg_string(lcfg, 1);
1955                 cfg = (struct config_llog_instance *)lustre_cfg_buf(lcfg, 2);
1956                 sb = *(struct super_block **)lustre_cfg_buf(lcfg, 3);
1957
1958                 CDEBUG(D_MGC, "parse_log %s from %d\n", logname,
1959                        cfg->cfg_last_idx);
1960
1961                 /* We're only called through here on the initial mount */
1962                 rc = config_log_add(obd, logname, cfg, sb);
1963                 if (rc)
1964                         break;
1965                 cld = config_log_find(logname, cfg);
1966                 if (cld == NULL) {
1967                         rc = -ENOENT;
1968                         break;
1969                 }
1970
1971                 /* COMPAT_146 */
1972                 /* FIXME only set this for old logs!  Right now this forces
1973                    us to always skip the "inside markers" check */
1974                 cld->cld_cfg.cfg_flags |= CFG_F_COMPAT146;
1975
1976                 rc = mgc_process_log(obd, cld);
1977                 if (rc == 0 && cld->cld_recover != NULL) {
1978                         if (OCD_HAS_FLAG(&obd->u.cli.cl_import->
1979                                          imp_connect_data, IMP_RECOV)) {
1980                                 rc = mgc_process_log(obd, cld->cld_recover);
1981                         } else {
1982                                 struct config_llog_data *cir = cld->cld_recover;
1983                                 cld->cld_recover = NULL;
1984                                 config_log_put(cir);
1985                         }
1986                         if (rc)
1987                                 CERROR("Cannot process recover llog %d\n", rc);
1988                 }
1989
1990                 if (rc == 0 && cld->cld_params != NULL) {
1991                         rc = mgc_process_log(obd, cld->cld_params);
1992                         if (rc == -ENOENT) {
1993                                 CDEBUG(D_MGC, "There is no params "
1994                                               "config file yet\n");
1995                                 rc = 0;
1996                         }
1997                         /* params log is optional */
1998                         if (rc)
1999                                 CERROR("%s: can't process params llog: rc = %d\n",
2000                                        obd->obd_name, rc);
2001                 }
2002                 config_log_put(cld);
2003
2004                 break;
2005         }
2006         case LCFG_LOG_END: {
2007                 logname = lustre_cfg_string(lcfg, 1);
2008
2009                 if (lcfg->lcfg_bufcount >= 2)
2010                         cfg = (struct config_llog_instance *)lustre_cfg_buf(
2011                                 lcfg, 2);
2012                 rc = config_log_end(logname, cfg);
2013                 break;
2014         }
2015         default: {
2016                 CERROR("Unknown command: %d\n", lcfg->lcfg_command);
2017                 GOTO(out, rc = -EINVAL);
2018
2019         }
2020         }
2021 out:
2022         RETURN(rc);
2023 }
2024
2025 struct obd_ops mgc_obd_ops = {
2026         .o_owner        = THIS_MODULE,
2027         .o_setup        = mgc_setup,
2028         .o_precleanup   = mgc_precleanup,
2029         .o_cleanup      = mgc_cleanup,
2030         .o_add_conn     = client_import_add_conn,
2031         .o_del_conn     = client_import_del_conn,
2032         .o_connect      = client_connect_import,
2033         .o_disconnect   = client_disconnect_export,
2034         .o_set_info_async = mgc_set_info_async,
2035         .o_get_info       = mgc_get_info,
2036         .o_import_event = mgc_import_event,
2037         .o_process_config = mgc_process_config,
2038 };
2039
2040 int __init mgc_init(void)
2041 {
2042         return class_register_type(&mgc_obd_ops, NULL, true, NULL,
2043                                    LUSTRE_MGC_NAME, NULL);
2044 }
2045
2046 static void /*__exit*/ mgc_exit(void)
2047 {
2048         class_unregister_type(LUSTRE_MGC_NAME);
2049 }
2050
2051 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
2052 MODULE_DESCRIPTION("Lustre Management Client");
2053 MODULE_LICENSE("GPL");
2054
2055 module_init(mgc_init);
2056 module_exit(mgc_exit);