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, 2012, 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 #ifdef __KERNEL__
  45 # include <linux/module.h>
  46 # include <linux/pagemap.h>
  47 # include <linux/miscdevice.h>
  48 # include <linux/init.h>
  49 #else
  50 # include <liblustre.h>
  51 #endif
  52
  53 #include <obd_class.h>
  54 #include <lustre_dlm.h>
  55 #include <lprocfs_status.h>
  56 #include <lustre_log.h>
  57 #include <lustre_fsfilt.h>
  58 #include <lustre_disk.h>
  59 #include "mgc_internal.h"
  60
  61 static int mgc_name2resid(char *name, int len, struct ldlm_res_id *res_id,
  62                           int type)
  63 {
  64         __u64 resname = 0;
  65
  66         if (len > 8) {
  67                 CERROR("name too long: %s\n", name);
  68                 return -EINVAL;
  69         }
  70         if (len <= 0) {
  71                 CERROR("missing name: %s\n", name);
  72                 return -EINVAL;
  73         }
  74         memcpy(&resname, name, len);
  75
  76         /* Always use the same endianness for the resid */
  77         memset(res_id, 0, sizeof(*res_id));
  78         res_id->name[0] = cpu_to_le64(resname);
  79         /* XXX: unfortunately, sptlprc and config llog share one lock */
  80         switch(type) {
  81         case CONFIG_T_CONFIG:
  82         case CONFIG_T_SPTLRPC:
  83                 resname = 0;
  84                 break;
  85         case CONFIG_T_RECOVER:
  86                 resname = type;
  87                 break;
  88         default:
  89                 LBUG();
  90         }
  91         res_id->name[1] = cpu_to_le64(resname);
  92         CDEBUG(D_MGC, "log %s to resid "LPX64"/"LPX64" (%.8s)\n", name,
  93                res_id->name[0], res_id->name[1], (char *)&res_id->name[0]);
  94         return 0;
  95 }
  96
  97 int mgc_fsname2resid(char *fsname, struct ldlm_res_id *res_id, int type)
  98 {
  99         /* fsname is at most 8 chars long, maybe contain "-".
 100          * e.g. "lustre", "SUN-000" */
 101         return mgc_name2resid(fsname, strlen(fsname), res_id, type);
 102 }
 103 EXPORT_SYMBOL(mgc_fsname2resid);
 104
 105 int mgc_logname2resid(char *logname, struct ldlm_res_id *res_id, int type)
 106 {
 107         char *name_end;
 108         int len;
 109
 110         /* logname consists of "fsname-nodetype".
 111          * e.g. "lustre-MDT0001", "SUN-000-client" */
 112         name_end = strrchr(logname, '-');
 113         LASSERT(name_end);
 114         len = name_end - logname;
 115         return mgc_name2resid(logname, len, res_id, type);
 116 }
 117
 118 /********************** config llog list **********************/
 119 static CFS_LIST_HEAD(config_llog_list);
 120 static DEFINE_SPINLOCK(config_list_lock);
 121
 122 /* Take a reference to a config log */
 123 static int config_log_get(struct config_llog_data *cld)
 124 {
 125         ENTRY;
 126         cfs_atomic_inc(&cld->cld_refcount);
 127         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 128                cfs_atomic_read(&cld->cld_refcount));
 129         RETURN(0);
 130 }
 131
 132 /* Drop a reference to a config log.  When no longer referenced,
 133    we can free the config log data */
 134 static void config_log_put(struct config_llog_data *cld)
 135 {
 136         ENTRY;
 137
 138         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 139                cfs_atomic_read(&cld->cld_refcount));
 140         LASSERT(cfs_atomic_read(&cld->cld_refcount) > 0);
 141
 142         /* spinlock to make sure no item with 0 refcount in the list */
 143         if (cfs_atomic_dec_and_lock(&cld->cld_refcount, &config_list_lock)) {
 144                 cfs_list_del(&cld->cld_list_chain);
 145                 spin_unlock(&config_list_lock);
 146
 147                 CDEBUG(D_MGC, "dropping config log %s\n", cld->cld_logname);
 148
 149                 if (cld->cld_recover)
 150                         config_log_put(cld->cld_recover);
 151                 if (cld->cld_sptlrpc)
 152                         config_log_put(cld->cld_sptlrpc);
 153                 if (cld_is_sptlrpc(cld))
 154                         sptlrpc_conf_log_stop(cld->cld_logname);
 155
 156                 class_export_put(cld->cld_mgcexp);
 157                 OBD_FREE(cld, sizeof(*cld) + strlen(cld->cld_logname) + 1);
 158         }
 159
 160         EXIT;
 161 }
 162
 163 /* Find a config log by name */
 164 static
 165 struct config_llog_data *config_log_find(char *logname,
 166                                          struct config_llog_instance *cfg)
 167 {
 168         struct config_llog_data *cld;
 169         struct config_llog_data *found = NULL;
 170         void *                   instance;
 171         ENTRY;
 172
 173         LASSERT(logname != NULL);
 174
 175         instance = cfg ? cfg->cfg_instance : NULL;
 176         spin_lock(&config_list_lock);
 177         cfs_list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 178                 /* check if instance equals */
 179                 if (instance != cld->cld_cfg.cfg_instance)
 180                         continue;
 181
 182                 /* instance may be NULL, should check name */
 183                 if (strcmp(logname, cld->cld_logname) == 0) {
 184                         found = cld;
 185                         break;
 186                 }
 187         }
 188         if (found) {
 189                 cfs_atomic_inc(&found->cld_refcount);
 190                 LASSERT(found->cld_stopping == 0 || cld_is_sptlrpc(found) == 0);
 191         }
 192         spin_unlock(&config_list_lock);
 193         RETURN(found);
 194 }
 195
 196 static
 197 struct config_llog_data *do_config_log_add(struct obd_device *obd,
 198                                            char *logname,
 199                                            int type,
 200                                            struct config_llog_instance *cfg,
 201                                            struct super_block *sb)
 202 {
 203         struct config_llog_data *cld;
 204         int                      rc;
 205         ENTRY;
 206
 207         CDEBUG(D_MGC, "do adding config log %s:%p\n", logname,
 208                cfg ? cfg->cfg_instance : 0);
 209
 210         OBD_ALLOC(cld, sizeof(*cld) + strlen(logname) + 1);
 211         if (!cld)
 212                 RETURN(ERR_PTR(-ENOMEM));
 213
 214         strcpy(cld->cld_logname, logname);
 215         if (cfg)
 216                 cld->cld_cfg = *cfg;
 217         else
 218                 cld->cld_cfg.cfg_callback = class_config_llog_handler;
 219         mutex_init(&cld->cld_lock);
 220         cld->cld_cfg.cfg_last_idx = 0;
 221         cld->cld_cfg.cfg_flags = 0;
 222         cld->cld_cfg.cfg_sb = sb;
 223         cld->cld_type = type;
 224         cfs_atomic_set(&cld->cld_refcount, 1);
 225
 226         /* Keep the mgc around until we are done */
 227         cld->cld_mgcexp = class_export_get(obd->obd_self_export);
 228
 229         if (cld_is_sptlrpc(cld)) {
 230                 sptlrpc_conf_log_start(logname);
 231                 cld->cld_cfg.cfg_obdname = obd->obd_name;
 232         }
 233
 234         rc = mgc_logname2resid(logname, &cld->cld_resid, type);
 235
 236         spin_lock(&config_list_lock);
 237         cfs_list_add(&cld->cld_list_chain, &config_llog_list);
 238         spin_unlock(&config_list_lock);
 239
 240         if (rc) {
 241                 config_log_put(cld);
 242                 RETURN(ERR_PTR(rc));
 243         }
 244
 245         if (cld_is_sptlrpc(cld)) {
 246                 rc = mgc_process_log(obd, cld);
 247                 if (rc && rc != -ENOENT)
 248                         CERROR("failed processing sptlrpc log: %d\n", rc);
 249         }
 250
 251         RETURN(cld);
 252 }
 253
 254 static struct config_llog_data *config_recover_log_add(struct obd_device *obd,
 255         char *fsname,
 256         struct config_llog_instance *cfg,
 257         struct super_block *sb)
 258 {
 259         struct config_llog_instance lcfg = *cfg;
 260         struct lustre_sb_info *lsi = s2lsi(sb);
 261         struct config_llog_data *cld;
 262         char logname[32];
 263
 264         if (IS_OST(lsi))
 265                 return NULL;
 266
 267         /* for osp-on-ost, see lustre_start_osp() */
 268         if (IS_MDT(lsi) && lcfg.cfg_instance)
 269                 return NULL;
 270
 271         /* we have to use different llog for clients and mdts for cmd
 272          * where only clients are notified if one of cmd server restarts */
 273         LASSERT(strlen(fsname) < sizeof(logname) / 2);
 274         strcpy(logname, fsname);
 275         if (IS_SERVER(lsi)) { /* mdt */
 276                 LASSERT(lcfg.cfg_instance == NULL);
 277                 lcfg.cfg_instance = sb;
 278                 strcat(logname, "-mdtir");
 279         } else {
 280                 LASSERT(lcfg.cfg_instance != NULL);
 281                 strcat(logname, "-cliir");
 282         }
 283
 284         cld = do_config_log_add(obd, logname, CONFIG_T_RECOVER, &lcfg, sb);
 285         return cld;
 286 }
 287
 288
 289 /** Add this log to the list of active logs watched by an MGC.
 290  * Active means we're watching for updates.
 291  * We have one active log per "mount" - client instance or servername.
 292  * Each instance may be at a different point in the log.
 293  */
 294 static int config_log_add(struct obd_device *obd, char *logname,
 295                           struct config_llog_instance *cfg,
 296                           struct super_block *sb)
 297 {
 298         struct lustre_sb_info *lsi = s2lsi(sb);
 299         struct config_llog_data *cld;
 300         struct config_llog_data *sptlrpc_cld;
 301         char                     seclogname[32];
 302         char                    *ptr;
 303         ENTRY;
 304
 305         CDEBUG(D_MGC, "adding config log %s:%p\n", logname, cfg->cfg_instance);
 306
 307         /*
 308          * for each regular log, the depended sptlrpc log name is
 309          * <fsname>-sptlrpc. multiple regular logs may share one sptlrpc log.
 310          */
 311         ptr = strrchr(logname, '-');
 312         if (ptr == NULL || ptr - logname > 8) {
 313                 CERROR("logname %s is too long\n", logname);
 314                 RETURN(-EINVAL);
 315         }
 316
 317         memcpy(seclogname, logname, ptr - logname);
 318         strcpy(seclogname + (ptr - logname), "-sptlrpc");
 319
 320         sptlrpc_cld = config_log_find(seclogname, NULL);
 321         if (sptlrpc_cld == NULL) {
 322                 sptlrpc_cld = do_config_log_add(obd, seclogname,
 323                                                 CONFIG_T_SPTLRPC, NULL, NULL);
 324                 if (IS_ERR(sptlrpc_cld)) {
 325                         CERROR("can't create sptlrpc log: %s\n", seclogname);
 326                         RETURN(PTR_ERR(sptlrpc_cld));
 327                 }
 328         }
 329
 330         cld = do_config_log_add(obd, logname, CONFIG_T_CONFIG, cfg, sb);
 331         if (IS_ERR(cld)) {
 332                 CERROR("can't create log: %s\n", logname);
 333                 config_log_put(sptlrpc_cld);
 334                 RETURN(PTR_ERR(cld));
 335         }
 336
 337         cld->cld_sptlrpc = sptlrpc_cld;
 338
 339         LASSERT(lsi->lsi_lmd);
 340         if (!(lsi->lsi_lmd->lmd_flags & LMD_FLG_NOIR)) {
 341                 struct config_llog_data *recover_cld;
 342                 *strrchr(seclogname, '-') = 0;
 343                 recover_cld = config_recover_log_add(obd, seclogname, cfg, sb);
 344                 if (IS_ERR(recover_cld)) {
 345                         config_log_put(cld);
 346                         RETURN(PTR_ERR(recover_cld));
 347                 }
 348                 cld->cld_recover = recover_cld;
 349         }
 350
 351         RETURN(0);
 352 }
 353
 354 DEFINE_MUTEX(llog_process_lock);
 355
 356 /** Stop watching for updates on this log.
 357  */
 358 static int config_log_end(char *logname, struct config_llog_instance *cfg)
 359 {
 360         struct config_llog_data *cld;
 361         struct config_llog_data *cld_sptlrpc = NULL;
 362         struct config_llog_data *cld_recover = NULL;
 363         int rc = 0;
 364         ENTRY;
 365
 366         cld = config_log_find(logname, cfg);
 367         if (cld == NULL)
 368                 RETURN(-ENOENT);
 369
 370         mutex_lock(&cld->cld_lock);
 371         /*
 372          * if cld_stopping is set, it means we didn't start the log thus
 373          * not owning the start ref. this can happen after previous umount:
 374          * the cld still hanging there waiting for lock cancel, and we
 375          * remount again but failed in the middle and call log_end without
 376          * calling start_log.
 377          */
 378         if (unlikely(cld->cld_stopping)) {
 379                 mutex_unlock(&cld->cld_lock);
 380                 /* drop the ref from the find */
 381                 config_log_put(cld);
 382                 RETURN(rc);
 383         }
 384
 385         cld->cld_stopping = 1;
 386
 387         cld_recover = cld->cld_recover;
 388         cld->cld_recover = NULL;
 389         mutex_unlock(&cld->cld_lock);
 390
 391         if (cld_recover) {
 392                 mutex_lock(&cld_recover->cld_lock);
 393                 cld_recover->cld_stopping = 1;
 394                 mutex_unlock(&cld_recover->cld_lock);
 395                 config_log_put(cld_recover);
 396         }
 397
 398         spin_lock(&config_list_lock);
 399         cld_sptlrpc = cld->cld_sptlrpc;
 400         cld->cld_sptlrpc = NULL;
 401         spin_unlock(&config_list_lock);
 402
 403         if (cld_sptlrpc)
 404                 config_log_put(cld_sptlrpc);
 405
 406         /* drop the ref from the find */
 407         config_log_put(cld);
 408         /* drop the start ref */
 409         config_log_put(cld);
 410
 411         CDEBUG(D_MGC, "end config log %s (%d)\n", logname ? logname : "client",
 412                rc);
 413         RETURN(rc);
 414 }
 415
 416 int lprocfs_mgc_rd_ir_state(char *page, char **start, off_t off,
 417                             int count, int *eof, void *data)
 418 {
 419         struct obd_device       *obd = data;
 420         struct obd_import       *imp = obd->u.cli.cl_import;
 421         struct obd_connect_data *ocd = &imp->imp_connect_data;
 422         struct config_llog_data *cld;
 423         int rc = 0;
 424         ENTRY;
 425
 426         rc = snprintf(page, count, "imperative_recovery: %s\n",
 427                       OCD_HAS_FLAG(ocd, IMP_RECOV) ? "ENABLED" : "DISABLED");
 428         rc += snprintf(page + rc, count - rc, "client_state:\n");
 429
 430         spin_lock(&config_list_lock);
 431         cfs_list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 432                 if (cld->cld_recover == NULL)
 433                         continue;
 434                 rc += snprintf(page + rc, count - rc,
 435                                "    - { client: %s, nidtbl_version: %u }\n",
 436                                cld->cld_logname,
 437                                cld->cld_recover->cld_cfg.cfg_last_idx);
 438         }
 439         spin_unlock(&config_list_lock);
 440
 441         RETURN(rc);
 442 }
 443
 444 /* reenqueue any lost locks */
 445 #define RQ_RUNNING 0x1
 446 #define RQ_NOW     0x2
 447 #define RQ_LATER   0x4
 448 #define RQ_STOP    0x8
 449 static int                    rq_state = 0;
 450 static cfs_waitq_t            rq_waitq;
 451 static DECLARE_COMPLETION(rq_exit);
 452
 453 static void do_requeue(struct config_llog_data *cld)
 454 {
 455         ENTRY;
 456         LASSERT(cfs_atomic_read(&cld->cld_refcount) > 0);
 457
 458         /* Do not run mgc_process_log on a disconnected export or an
 459            export which is being disconnected. Take the client
 460            semaphore to make the check non-racy. */
 461         down_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 462         if (cld->cld_mgcexp->exp_obd->u.cli.cl_conn_count != 0) {
 463                 CDEBUG(D_MGC, "updating log %s\n", cld->cld_logname);
 464                 mgc_process_log(cld->cld_mgcexp->exp_obd, cld);
 465         } else {
 466                 CDEBUG(D_MGC, "disconnecting, won't update log %s\n",
 467                        cld->cld_logname);
 468         }
 469         up_read(&cld->cld_mgcexp->exp_obd->u.cli.cl_sem);
 470
 471         EXIT;
 472 }
 473
 474 /* this timeout represents how many seconds MGC should wait before
 475  * requeue config and recover lock to the MGS. We need to randomize this
 476  * in order to not flood the MGS.
 477  */
 478 #define MGC_TIMEOUT_MIN_SECONDS   5
 479 #define MGC_TIMEOUT_RAND_CENTISEC 0x1ff /* ~500 */
 480
 481 static int mgc_requeue_thread(void *data)
 482 {
 483         char name[] = "ll_cfg_requeue";
 484         int rc = 0;
 485         ENTRY;
 486
 487         cfs_daemonize(name);
 488
 489         CDEBUG(D_MGC, "Starting requeue thread\n");
 490
 491         /* Keep trying failed locks periodically */
 492         spin_lock(&config_list_lock);
 493         rq_state |= RQ_RUNNING;
 494         while (1) {
 495                 struct l_wait_info lwi;
 496                 struct config_llog_data *cld, *cld_prev;
 497                 int rand = cfs_rand() & MGC_TIMEOUT_RAND_CENTISEC;
 498                 int stopped = !!(rq_state & RQ_STOP);
 499                 int to;
 500
 501                 /* Any new or requeued lostlocks will change the state */
 502                 rq_state &= ~(RQ_NOW | RQ_LATER);
 503                 spin_unlock(&config_list_lock);
 504
 505                 /* Always wait a few seconds to allow the server who
 506                    caused the lock revocation to finish its setup, plus some
 507                    random so everyone doesn't try to reconnect at once. */
 508                 to = MGC_TIMEOUT_MIN_SECONDS * CFS_HZ;
 509                 to += rand * CFS_HZ / 100; /* rand is centi-seconds */
 510                 lwi = LWI_TIMEOUT(to, NULL, NULL);
 511                 l_wait_event(rq_waitq, rq_state & RQ_STOP, &lwi);
 512
 513                 /*
 514                  * iterate & processing through the list. for each cld, process
 515                  * its depending sptlrpc cld firstly (if any) and then itself.
 516                  *
 517                  * it's guaranteed any item in the list must have
 518                  * reference > 0; and if cld_lostlock is set, at
 519                  * least one reference is taken by the previous enqueue.
 520                  */
 521                 cld_prev = NULL;
 522
 523                 spin_lock(&config_list_lock);
 524                 cfs_list_for_each_entry(cld, &config_llog_list,
 525                                         cld_list_chain) {
 526                         if (!cld->cld_lostlock)
 527                                 continue;
 528
 529                         spin_unlock(&config_list_lock);
 530
 531                         LASSERT(cfs_atomic_read(&cld->cld_refcount) > 0);
 532
 533                         /* Whether we enqueued again or not in mgc_process_log,
 534                          * we're done with the ref from the old enqueue */
 535                         if (cld_prev)
 536                                 config_log_put(cld_prev);
 537                         cld_prev = cld;
 538
 539                         cld->cld_lostlock = 0;
 540                         if (likely(!stopped))
 541                                 do_requeue(cld);
 542
 543                         spin_lock(&config_list_lock);
 544                 }
 545                 spin_unlock(&config_list_lock);
 546                 if (cld_prev)
 547                         config_log_put(cld_prev);
 548
 549                 /* break after scanning the list so that we can drop
 550                  * refcount to losing lock clds */
 551                 if (unlikely(stopped)) {
 552                         spin_lock(&config_list_lock);
 553                         break;
 554                 }
 555
 556                 /* Wait a bit to see if anyone else needs a requeue */
 557                 lwi = (struct l_wait_info) { 0 };
 558                 l_wait_event(rq_waitq, rq_state & (RQ_NOW | RQ_STOP),
 559                              &lwi);
 560                 spin_lock(&config_list_lock);
 561         }
 562         /* spinlock and while guarantee RQ_NOW and RQ_LATER are not set */
 563         rq_state &= ~RQ_RUNNING;
 564         spin_unlock(&config_list_lock);
 565
 566         complete(&rq_exit);
 567
 568         CDEBUG(D_MGC, "Ending requeue thread\n");
 569         RETURN(rc);
 570 }
 571
 572 /* Add a cld to the list to requeue.  Start the requeue thread if needed.
 573    We are responsible for dropping the config log reference from here on out. */
 574 static void mgc_requeue_add(struct config_llog_data *cld)
 575 {
 576         ENTRY;
 577
 578         CDEBUG(D_INFO, "log %s: requeue (r=%d sp=%d st=%x)\n",
 579                cld->cld_logname, cfs_atomic_read(&cld->cld_refcount),
 580                cld->cld_stopping, rq_state);
 581         LASSERT(cfs_atomic_read(&cld->cld_refcount) > 0);
 582
 583         mutex_lock(&cld->cld_lock);
 584         if (cld->cld_stopping || cld->cld_lostlock) {
 585                 mutex_unlock(&cld->cld_lock);
 586                 RETURN_EXIT;
 587         }
 588         /* this refcount will be released in mgc_requeue_thread. */
 589         config_log_get(cld);
 590         cld->cld_lostlock = 1;
 591         mutex_unlock(&cld->cld_lock);
 592
 593         /* Hold lock for rq_state */
 594         spin_lock(&config_list_lock);
 595         if (rq_state & RQ_STOP) {
 596                 spin_unlock(&config_list_lock);
 597                 cld->cld_lostlock = 0;
 598                 config_log_put(cld);
 599         } else {
 600                 rq_state |= RQ_NOW;
 601                 spin_unlock(&config_list_lock);
 602                 cfs_waitq_signal(&rq_waitq);
 603         }
 604         EXIT;
 605 }
 606
 607 /********************** class fns **********************/
 608
 609 static int mgc_fs_setup(struct obd_device *obd, struct super_block *sb,
 610                         struct vfsmount *mnt)
 611 {
 612         struct lvfs_run_ctxt saved;
 613         struct lustre_sb_info *lsi = s2lsi(sb);
 614         struct client_obd *cli = &obd->u.cli;
 615         struct dentry *dentry;
 616         char *label;
 617         int err = 0;
 618         ENTRY;
 619
 620         LASSERT(lsi);
 621         LASSERT(lsi->lsi_srv_mnt == mnt);
 622
 623         /* The mgc fs exclusion sem. Only one fs can be setup at a time. */
 624         down(&cli->cl_mgc_sem);
 625
 626         cfs_cleanup_group_info();
 627
 628         obd->obd_fsops = fsfilt_get_ops(lsi->lsi_fstype);
 629         if (IS_ERR(obd->obd_fsops)) {
 630                 up(&cli->cl_mgc_sem);
 631                 CERROR("%s: No fstype %s: rc = %ld\n", lsi->lsi_fstype,
 632                        obd->obd_name, PTR_ERR(obd->obd_fsops));
 633                 RETURN(PTR_ERR(obd->obd_fsops));
 634         }
 635
 636         cli->cl_mgc_vfsmnt = mnt;
 637         err = fsfilt_setup(obd, mnt->mnt_sb);
 638         if (err)
 639                 GOTO(err_ops, err);
 640
 641         OBD_SET_CTXT_MAGIC(&obd->obd_lvfs_ctxt);
 642         obd->obd_lvfs_ctxt.pwdmnt = mnt;
 643         obd->obd_lvfs_ctxt.pwd = mnt->mnt_root;
 644         obd->obd_lvfs_ctxt.fs = get_ds();
 645
 646         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 647         dentry = ll_lookup_one_len(MOUNT_CONFIGS_DIR, cfs_fs_pwd(current->fs),
 648                                    strlen(MOUNT_CONFIGS_DIR));
 649         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 650         if (IS_ERR(dentry)) {
 651                 err = PTR_ERR(dentry);
 652                 CERROR("cannot lookup %s directory: rc = %d\n",
 653                        MOUNT_CONFIGS_DIR, err);
 654                 GOTO(err_ops, err);
 655         }
 656         cli->cl_mgc_configs_dir = dentry;
 657
 658         /* We take an obd ref to insure that we can't get to mgc_cleanup
 659            without calling mgc_fs_cleanup first. */
 660         class_incref(obd, "mgc_fs", obd);
 661
 662         label = fsfilt_get_label(obd, mnt->mnt_sb);
 663         if (label)
 664                 CDEBUG(D_MGC, "MGC using disk labelled=%s\n", label);
 665
 666         /* We keep the cl_mgc_sem until mgc_fs_cleanup */
 667         RETURN(0);
 668
 669 err_ops:
 670         fsfilt_put_ops(obd->obd_fsops);
 671         obd->obd_fsops = NULL;
 672         cli->cl_mgc_vfsmnt = NULL;
 673         up(&cli->cl_mgc_sem);
 674         RETURN(err);
 675 }
 676
 677 static int mgc_fs_cleanup(struct obd_device *obd)
 678 {
 679         struct client_obd *cli = &obd->u.cli;
 680         int rc = 0;
 681         ENTRY;
 682
 683         LASSERT(cli->cl_mgc_vfsmnt != NULL);
 684
 685         if (cli->cl_mgc_configs_dir != NULL) {
 686                 struct lvfs_run_ctxt saved;
 687                 push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 688                 l_dput(cli->cl_mgc_configs_dir);
 689                 cli->cl_mgc_configs_dir = NULL;
 690                 pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 691                 class_decref(obd, "mgc_fs", obd);
 692         }
 693
 694         cli->cl_mgc_vfsmnt = NULL;
 695         if (obd->obd_fsops)
 696                 fsfilt_put_ops(obd->obd_fsops);
 697
 698         up(&cli->cl_mgc_sem);
 699
 700         RETURN(rc);
 701 }
 702
 703 static cfs_atomic_t mgc_count = CFS_ATOMIC_INIT(0);
 704 static int mgc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 705 {
 706         int rc = 0;
 707         ENTRY;
 708
 709         switch (stage) {
 710         case OBD_CLEANUP_EARLY:
 711                 break;
 712         case OBD_CLEANUP_EXPORTS:
 713                 if (cfs_atomic_dec_and_test(&mgc_count)) {
 714                         int running;
 715                         /* stop requeue thread */
 716                         spin_lock(&config_list_lock);
 717                         running = rq_state & RQ_RUNNING;
 718                         if (running)
 719                                 rq_state |= RQ_STOP;
 720                         spin_unlock(&config_list_lock);
 721                         if (running) {
 722                                 cfs_waitq_signal(&rq_waitq);
 723                                 wait_for_completion(&rq_exit);
 724                         }
 725                 }
 726                 obd_cleanup_client_import(obd);
 727                 rc = obd_llog_finish(obd, 0);
 728                 if (rc != 0)
 729                         CERROR("failed to cleanup llogging subsystems\n");
 730                 break;
 731         }
 732         RETURN(rc);
 733 }
 734
 735 static int mgc_cleanup(struct obd_device *obd)
 736 {
 737         struct client_obd *cli = &obd->u.cli;
 738         int rc;
 739         ENTRY;
 740
 741         LASSERT(cli->cl_mgc_vfsmnt == NULL);
 742
 743         /* COMPAT_146 - old config logs may have added profiles we don't
 744            know about */
 745         if (obd->obd_type->typ_refcnt <= 1)
 746                 /* Only for the last mgc */
 747                 class_del_profiles();
 748
 749         lprocfs_obd_cleanup(obd);
 750         ptlrpcd_decref();
 751
 752         rc = client_obd_cleanup(obd);
 753         RETURN(rc);
 754 }
 755
 756 static int mgc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 757 {
 758         struct lprocfs_static_vars lvars;
 759         int rc;
 760         ENTRY;
 761
 762         ptlrpcd_addref();
 763
 764         rc = client_obd_setup(obd, lcfg);
 765         if (rc)
 766                 GOTO(err_decref, rc);
 767
 768         rc = obd_llog_init(obd, &obd->obd_olg, obd, NULL);
 769         if (rc) {
 770                 CERROR("failed to setup llogging subsystems\n");
 771                 GOTO(err_cleanup, rc);
 772         }
 773
 774         lprocfs_mgc_init_vars(&lvars);
 775         lprocfs_obd_setup(obd, lvars.obd_vars);
 776         sptlrpc_lprocfs_cliobd_attach(obd);
 777
 778         if (cfs_atomic_inc_return(&mgc_count) == 1) {
 779                 rq_state = 0;
 780                 cfs_waitq_init(&rq_waitq);
 781
 782                 /* start requeue thread */
 783                 rc = cfs_create_thread(mgc_requeue_thread, NULL,
 784                                        CFS_DAEMON_FLAGS);
 785                 if (rc < 0) {
 786                         CERROR("%s: Cannot start requeue thread (%d),"
 787                                "no more log updates!\n",
 788                                obd->obd_name, rc);
 789                         GOTO(err_cleanup, rc);
 790                 }
 791                 /* rc is the pid of mgc_requeue_thread. */
 792                 rc = 0;
 793         }
 794
 795         RETURN(rc);
 796
 797 err_cleanup:
 798         client_obd_cleanup(obd);
 799 err_decref:
 800         ptlrpcd_decref();
 801         RETURN(rc);
 802 }
 803
 804 /* based on ll_mdc_blocking_ast */
 805 static int mgc_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 806                             void *data, int flag)
 807 {
 808         struct lustre_handle lockh;
 809         struct config_llog_data *cld = (struct config_llog_data *)data;
 810         int rc = 0;
 811         ENTRY;
 812
 813         switch (flag) {
 814         case LDLM_CB_BLOCKING:
 815                 /* mgs wants the lock, give it up... */
 816                 LDLM_DEBUG(lock, "MGC blocking CB");
 817                 ldlm_lock2handle(lock, &lockh);
 818                 rc = ldlm_cli_cancel(&lockh);
 819                 break;
 820         case LDLM_CB_CANCELING:
 821                 /* We've given up the lock, prepare ourselves to update. */
 822                 LDLM_DEBUG(lock, "MGC cancel CB");
 823
 824                 CDEBUG(D_MGC, "Lock res "LPX64" (%.8s)\n",
 825                        lock->l_resource->lr_name.name[0],
 826                        (char *)&lock->l_resource->lr_name.name[0]);
 827
 828                 if (!cld) {
 829                         CDEBUG(D_INFO, "missing data, won't requeue\n");
 830                         break;
 831                 }
 832
 833                 /* held at mgc_process_log(). */
 834                 LASSERT(cfs_atomic_read(&cld->cld_refcount) > 0);
 835                 /* Are we done with this log? */
 836                 if (cld->cld_stopping) {
 837                         CDEBUG(D_MGC, "log %s: stopping, won't requeue\n",
 838                                cld->cld_logname);
 839                         config_log_put(cld);
 840                         break;
 841                 }
 842                 /* Make sure not to re-enqueue when the mgc is stopping
 843                    (we get called from client_disconnect_export) */
 844                 if (!lock->l_conn_export ||
 845                     !lock->l_conn_export->exp_obd->u.cli.cl_conn_count) {
 846                         CDEBUG(D_MGC, "log %.8s: disconnecting, won't requeue\n",
 847                                cld->cld_logname);
 848                         config_log_put(cld);
 849                         break;
 850                 }
 851
 852                 /* Re-enqueue now */
 853                 mgc_requeue_add(cld);
 854                 config_log_put(cld);
 855                 break;
 856         default:
 857                 LBUG();
 858         }
 859
 860         RETURN(rc);
 861 }
 862
 863 /* Not sure where this should go... */
 864 #define  MGC_ENQUEUE_LIMIT 50
 865 #define  MGC_TARGET_REG_LIMIT 10
 866 #define  MGC_SEND_PARAM_LIMIT 10
 867
 868 /* Send parameter to MGS*/
 869 static int mgc_set_mgs_param(struct obd_export *exp,
 870                              struct mgs_send_param *msp)
 871 {
 872         struct ptlrpc_request *req;
 873         struct mgs_send_param *req_msp, *rep_msp;
 874         int rc;
 875         ENTRY;
 876
 877         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
 878                                         &RQF_MGS_SET_INFO, LUSTRE_MGS_VERSION,
 879                                         MGS_SET_INFO);
 880         if (!req)
 881                 RETURN(-ENOMEM);
 882
 883         req_msp = req_capsule_client_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
 884         if (!req_msp) {
 885                 ptlrpc_req_finished(req);
 886                 RETURN(-ENOMEM);
 887         }
 888
 889         memcpy(req_msp, msp, sizeof(*req_msp));
 890         ptlrpc_request_set_replen(req);
 891
 892         /* Limit how long we will wait for the enqueue to complete */
 893         req->rq_delay_limit = MGC_SEND_PARAM_LIMIT;
 894         rc = ptlrpc_queue_wait(req);
 895         if (!rc) {
 896                 rep_msp = req_capsule_server_get(&req->rq_pill, &RMF_MGS_SEND_PARAM);
 897                 memcpy(msp, rep_msp, sizeof(*rep_msp));
 898         }
 899
 900         ptlrpc_req_finished(req);
 901
 902         RETURN(rc);
 903 }
 904
 905 /* Take a config lock so we can get cancel notifications */
 906 static int mgc_enqueue(struct obd_export *exp, struct lov_stripe_md *lsm,
 907                        __u32 type, ldlm_policy_data_t *policy, __u32 mode,
 908                        __u64 *flags, void *bl_cb, void *cp_cb, void *gl_cb,
 909                        void *data, __u32 lvb_len, void *lvb_swabber,
 910                        struct lustre_handle *lockh)
 911 {
 912         struct config_llog_data *cld = (struct config_llog_data *)data;
 913         struct ldlm_enqueue_info einfo = { type, mode, mgc_blocking_ast,
 914                          ldlm_completion_ast, NULL, NULL, NULL };
 915         struct ptlrpc_request *req;
 916         int short_limit = cld_is_sptlrpc(cld);
 917         int rc;
 918         ENTRY;
 919
 920         CDEBUG(D_MGC, "Enqueue for %s (res "LPX64")\n", cld->cld_logname,
 921                cld->cld_resid.name[0]);
 922
 923         /* We need a callback for every lockholder, so don't try to
 924            ldlm_lock_match (see rev 1.1.2.11.2.47) */
 925         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
 926                                         &RQF_LDLM_ENQUEUE, LUSTRE_DLM_VERSION,
 927                                         LDLM_ENQUEUE);
 928         if (req == NULL)
 929                 RETURN(-ENOMEM);
 930
 931         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER, 0);
 932         ptlrpc_request_set_replen(req);
 933
 934         /* check if this is server or client */
 935         if (cld->cld_cfg.cfg_sb) {
 936                 struct lustre_sb_info *lsi = s2lsi(cld->cld_cfg.cfg_sb);
 937                 if (lsi && IS_SERVER(lsi))
 938                         short_limit = 1;
 939         }
 940         /* Limit how long we will wait for the enqueue to complete */
 941         req->rq_delay_limit = short_limit ? 5 : MGC_ENQUEUE_LIMIT;
 942         rc = ldlm_cli_enqueue(exp, &req, &einfo, &cld->cld_resid, NULL, flags,
 943                               NULL, 0, LVB_T_NONE, lockh, 0);
 944         /* A failed enqueue should still call the mgc_blocking_ast,
 945            where it will be requeued if needed ("grant failed"). */
 946         ptlrpc_req_finished(req);
 947         RETURN(rc);
 948 }
 949
 950 static int mgc_cancel(struct obd_export *exp, struct lov_stripe_md *md,
 951                       __u32 mode, struct lustre_handle *lockh)
 952 {
 953         ENTRY;
 954
 955         ldlm_lock_decref(lockh, mode);
 956
 957         RETURN(0);
 958 }
 959
 960 static void mgc_notify_active(struct obd_device *unused)
 961 {
 962         /* wakeup mgc_requeue_thread to requeue mgc lock */
 963         spin_lock(&config_list_lock);
 964         rq_state |= RQ_NOW;
 965         spin_unlock(&config_list_lock);
 966         cfs_waitq_signal(&rq_waitq);
 967
 968         /* TODO: Help the MGS rebuild nidtbl. -jay */
 969 }
 970
 971 /* Send target_reg message to MGS */
 972 static int mgc_target_register(struct obd_export *exp,
 973                                struct mgs_target_info *mti)
 974 {
 975         struct ptlrpc_request  *req;
 976         struct mgs_target_info *req_mti, *rep_mti;
 977         int                     rc;
 978         ENTRY;
 979
 980         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
 981                                         &RQF_MGS_TARGET_REG, LUSTRE_MGS_VERSION,
 982                                         MGS_TARGET_REG);
 983         if (req == NULL)
 984                 RETURN(-ENOMEM);
 985
 986         req_mti = req_capsule_client_get(&req->rq_pill, &RMF_MGS_TARGET_INFO);
 987         if (!req_mti) {
 988                 ptlrpc_req_finished(req);
 989                 RETURN(-ENOMEM);
 990         }
 991
 992         memcpy(req_mti, mti, sizeof(*req_mti));
 993         ptlrpc_request_set_replen(req);
 994         CDEBUG(D_MGC, "register %s\n", mti->mti_svname);
 995         /* Limit how long we will wait for the enqueue to complete */
 996         req->rq_delay_limit = MGC_TARGET_REG_LIMIT;
 997
 998         rc = ptlrpc_queue_wait(req);
 999         if (!rc) {
1000                 rep_mti = req_capsule_server_get(&req->rq_pill,
1001                                                  &RMF_MGS_TARGET_INFO);
1002                 memcpy(mti, rep_mti, sizeof(*rep_mti));
1003                 CDEBUG(D_MGC, "register %s got index = %d\n",
1004                        mti->mti_svname, mti->mti_stripe_index);
1005         }
1006         ptlrpc_req_finished(req);
1007
1008         RETURN(rc);
1009 }
1010
1011 int mgc_set_info_async(const struct lu_env *env, struct obd_export *exp,
1012                        obd_count keylen, void *key, obd_count vallen,
1013                        void *val, struct ptlrpc_request_set *set)
1014 {
1015         int rc = -EINVAL;
1016         ENTRY;
1017
1018         /* Turn off initial_recov after we try all backup servers once */
1019         if (KEY_IS(KEY_INIT_RECOV_BACKUP)) {
1020                 struct obd_import *imp = class_exp2cliimp(exp);
1021                 int value;
1022                 if (vallen != sizeof(int))
1023                         RETURN(-EINVAL);
1024                 value = *(int *)val;
1025                 CDEBUG(D_MGC, "InitRecov %s %d/d%d:i%d:r%d:or%d:%s\n",
1026                        imp->imp_obd->obd_name, value,
1027                        imp->imp_deactive, imp->imp_invalid,
1028                        imp->imp_replayable, imp->imp_obd->obd_replayable,
1029                        ptlrpc_import_state_name(imp->imp_state));
1030                 /* Resurrect if we previously died */
1031                 if ((imp->imp_state != LUSTRE_IMP_FULL &&
1032                      imp->imp_state != LUSTRE_IMP_NEW) || value > 1)
1033                         ptlrpc_reconnect_import(imp);
1034                 RETURN(0);
1035         }
1036         /* FIXME move this to mgc_process_config */
1037         if (KEY_IS(KEY_REGISTER_TARGET)) {
1038                 struct mgs_target_info *mti;
1039                 if (vallen != sizeof(struct mgs_target_info))
1040                         RETURN(-EINVAL);
1041                 mti = (struct mgs_target_info *)val;
1042                 CDEBUG(D_MGC, "register_target %s %#x\n",
1043                        mti->mti_svname, mti->mti_flags);
1044                 rc =  mgc_target_register(exp, mti);
1045                 RETURN(rc);
1046         }
1047         if (KEY_IS(KEY_SET_FS)) {
1048                 struct super_block *sb = (struct super_block *)val;
1049                 struct lustre_sb_info *lsi;
1050                 if (vallen != sizeof(struct super_block))
1051                         RETURN(-EINVAL);
1052                 lsi = s2lsi(sb);
1053                 rc = mgc_fs_setup(exp->exp_obd, sb, lsi->lsi_srv_mnt);
1054                 if (rc) {
1055                         CERROR("set_fs got %d\n", rc);
1056                 }
1057                 RETURN(rc);
1058         }
1059         if (KEY_IS(KEY_CLEAR_FS)) {
1060                 if (vallen != 0)
1061                         RETURN(-EINVAL);
1062                 rc = mgc_fs_cleanup(exp->exp_obd);
1063                 if (rc) {
1064                         CERROR("clear_fs got %d\n", rc);
1065                 }
1066                 RETURN(rc);
1067         }
1068         if (KEY_IS(KEY_SET_INFO)) {
1069                 struct mgs_send_param *msp;
1070
1071                 msp = (struct mgs_send_param *)val;
1072                 rc =  mgc_set_mgs_param(exp, msp);
1073                 RETURN(rc);
1074         }
1075         if (KEY_IS(KEY_MGSSEC)) {
1076                 struct client_obd     *cli = &exp->exp_obd->u.cli;
1077                 struct sptlrpc_flavor  flvr;
1078
1079                 /*
1080                  * empty string means using current flavor, if which haven't
1081                  * been set yet, set it as null.
1082                  *
1083                  * if flavor has been set previously, check the asking flavor
1084                  * must match the existing one.
1085                  */
1086                 if (vallen == 0) {
1087                         if (cli->cl_flvr_mgc.sf_rpc != SPTLRPC_FLVR_INVALID)
1088                                 RETURN(0);
1089                         val = "null";
1090                         vallen = 4;
1091                 }
1092
1093                 rc = sptlrpc_parse_flavor(val, &flvr);
1094                 if (rc) {
1095                         CERROR("invalid sptlrpc flavor %s to MGS\n",
1096                                (char *) val);
1097                         RETURN(rc);
1098                 }
1099
1100                 /*
1101                  * caller already hold a mutex
1102                  */
1103                 if (cli->cl_flvr_mgc.sf_rpc == SPTLRPC_FLVR_INVALID) {
1104                         cli->cl_flvr_mgc = flvr;
1105                 } else if (memcmp(&cli->cl_flvr_mgc, &flvr,
1106                                   sizeof(flvr)) != 0) {
1107                         char    str[20];
1108
1109                         sptlrpc_flavor2name(&cli->cl_flvr_mgc,
1110                                             str, sizeof(str));
1111                         LCONSOLE_ERROR("asking sptlrpc flavor %s to MGS but "
1112                                        "currently %s is in use\n",
1113                                        (char *) val, str);
1114                         rc = -EPERM;
1115                 }
1116                 RETURN(rc);
1117         }
1118
1119         RETURN(rc);
1120 }
1121
1122 static int mgc_get_info(const struct lu_env *env, struct obd_export *exp,
1123                         __u32 keylen, void *key, __u32 *vallen, void *val,
1124                         struct lov_stripe_md *unused)
1125 {
1126         int rc = -EINVAL;
1127
1128         if (KEY_IS(KEY_CONN_DATA)) {
1129                 struct obd_import *imp = class_exp2cliimp(exp);
1130                 struct obd_connect_data *data = val;
1131
1132                 if (*vallen == sizeof(*data)) {
1133                         *data = imp->imp_connect_data;
1134                         rc = 0;
1135                 }
1136         }
1137
1138         return rc;
1139 }
1140
1141 static int mgc_import_event(struct obd_device *obd,
1142                             struct obd_import *imp,
1143                             enum obd_import_event event)
1144 {
1145         int rc = 0;
1146
1147         LASSERT(imp->imp_obd == obd);
1148         CDEBUG(D_MGC, "import event %#x\n", event);
1149
1150         switch (event) {
1151         case IMP_EVENT_DISCON:
1152                 /* MGC imports should not wait for recovery */
1153                 break;
1154         case IMP_EVENT_INACTIVE:
1155                 break;
1156         case IMP_EVENT_INVALIDATE: {
1157                 struct ldlm_namespace *ns = obd->obd_namespace;
1158                 ldlm_namespace_cleanup(ns, LDLM_FL_LOCAL_ONLY);
1159                 break;
1160         }
1161         case IMP_EVENT_ACTIVE:
1162                 CDEBUG(D_INFO, "%s: Reactivating import\n", obd->obd_name);
1163                 /* Clearing obd_no_recov allows us to continue pinging */
1164                 obd->obd_no_recov = 0;
1165                 mgc_notify_active(obd);
1166                 break;
1167         case IMP_EVENT_OCD:
1168                 break;
1169         case IMP_EVENT_DEACTIVATE:
1170         case IMP_EVENT_ACTIVATE:
1171                 break;
1172         default:
1173                 CERROR("Unknown import event %#x\n", event);
1174                 LBUG();
1175         }
1176         RETURN(rc);
1177 }
1178
1179 static int mgc_llog_init(struct obd_device *obd, struct obd_llog_group *olg,
1180                          struct obd_device *tgt, int *index)
1181 {
1182         struct llog_ctxt *ctxt;
1183         int rc;
1184         ENTRY;
1185
1186         LASSERT(olg == &obd->obd_olg);
1187
1188 #ifdef HAVE_LDISKFS_OSD
1189         rc = llog_setup(NULL, obd, olg, LLOG_CONFIG_ORIG_CTXT, tgt,
1190                         &llog_lvfs_ops);
1191         if (rc)
1192                 RETURN(rc);
1193 #endif
1194
1195         rc = llog_setup(NULL, obd, olg, LLOG_CONFIG_REPL_CTXT, tgt,
1196                         &llog_client_ops);
1197         if (rc)
1198                 GOTO(out, rc);
1199
1200         ctxt = llog_group_get_ctxt(olg, LLOG_CONFIG_REPL_CTXT);
1201         if (!ctxt)
1202                 GOTO(out, rc = -ENODEV);
1203
1204         llog_initiator_connect(ctxt);
1205         llog_ctxt_put(ctxt);
1206
1207         RETURN(0);
1208 out:
1209         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
1210         if (ctxt)
1211                 llog_cleanup(NULL, ctxt);
1212         RETURN(rc);
1213 }
1214
1215 static int mgc_llog_finish(struct obd_device *obd, int count)
1216 {
1217         struct llog_ctxt *ctxt;
1218
1219         ENTRY;
1220
1221         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
1222         if (ctxt)
1223                 llog_cleanup(NULL, ctxt);
1224
1225         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
1226         if (ctxt)
1227                 llog_cleanup(NULL, ctxt);
1228         RETURN(0);
1229 }
1230
1231 enum {
1232         CONFIG_READ_NRPAGES_INIT = 1 << (20 - CFS_PAGE_SHIFT),
1233         CONFIG_READ_NRPAGES      = 4
1234 };
1235
1236 static int mgc_apply_recover_logs(struct obd_device *mgc,
1237                                   struct config_llog_data *cld,
1238                                   __u64 max_version,
1239                                   void *data, int datalen, bool mne_swab)
1240 {
1241         struct config_llog_instance *cfg = &cld->cld_cfg;
1242         struct lustre_sb_info       *lsi = s2lsi(cfg->cfg_sb);
1243         struct mgs_nidtbl_entry *entry;
1244         struct lustre_cfg       *lcfg;
1245         struct lustre_cfg_bufs   bufs;
1246         u64   prev_version = 0;
1247         char *inst;
1248         char *buf;
1249         int   bufsz;
1250         int   pos;
1251         int   rc  = 0;
1252         int   off = 0;
1253         ENTRY;
1254
1255         LASSERT(cfg->cfg_instance != NULL);
1256         LASSERT(cfg->cfg_sb == cfg->cfg_instance);
1257
1258         OBD_ALLOC(inst, CFS_PAGE_SIZE);
1259         if (inst == NULL)
1260                 RETURN(-ENOMEM);
1261
1262         if (!IS_SERVER(lsi)) {
1263                 pos = snprintf(inst, CFS_PAGE_SIZE, "%p", cfg->cfg_instance);
1264                 if (pos >= CFS_PAGE_SIZE) {
1265                         OBD_FREE(inst, CFS_PAGE_SIZE);
1266                         return -E2BIG;
1267                 }
1268         } else {
1269                 LASSERT(IS_MDT(lsi));
1270                 rc = server_name2svname(lsi->lsi_svname, inst, NULL,
1271                                         CFS_PAGE_SIZE);
1272                 if (rc) {
1273                         OBD_FREE(inst, CFS_PAGE_SIZE);
1274                         RETURN(-EINVAL);
1275                 }
1276                 pos = strlen(inst);
1277         }
1278
1279         ++pos;
1280         buf   = inst + pos;
1281         bufsz = CFS_PAGE_SIZE - pos;
1282
1283         while (datalen > 0) {
1284                 int   entry_len = sizeof(*entry);
1285                 int   is_ost;
1286                 struct obd_device *obd;
1287                 char *obdname;
1288                 char *cname;
1289                 char *params;
1290                 char *uuid;
1291
1292                 rc = -EINVAL;
1293                 if (datalen < sizeof(*entry))
1294                         break;
1295
1296                 entry = (typeof(entry))(data + off);
1297
1298                 /* sanity check */
1299                 if (entry->mne_nid_type != 0) /* only support type 0 for ipv4 */
1300                         break;
1301                 if (entry->mne_nid_count == 0) /* at least one nid entry */
1302                         break;
1303                 if (entry->mne_nid_size != sizeof(lnet_nid_t))
1304                         break;
1305
1306                 entry_len += entry->mne_nid_count * entry->mne_nid_size;
1307                 if (datalen < entry_len) /* must have entry_len at least */
1308                         break;
1309
1310                 /* Keep this swab for normal mixed endian handling. LU-1644 */
1311                 if (mne_swab)
1312                         lustre_swab_mgs_nidtbl_entry(entry);
1313                 if (entry->mne_length > CFS_PAGE_SIZE) {
1314                         CERROR("MNE too large (%u)\n", entry->mne_length);
1315                         break;
1316                 }
1317
1318                 if (entry->mne_length < entry_len)
1319                         break;
1320
1321                 off     += entry->mne_length;
1322                 datalen -= entry->mne_length;
1323                 if (datalen < 0)
1324                         break;
1325
1326                 if (entry->mne_version > max_version) {
1327                         CERROR("entry index(%lld) is over max_index(%lld)\n",
1328                                entry->mne_version, max_version);
1329                         break;
1330                 }
1331
1332                 if (prev_version >= entry->mne_version) {
1333                         CERROR("index unsorted, prev %lld, now %lld\n",
1334                                prev_version, entry->mne_version);
1335                         break;
1336                 }
1337                 prev_version = entry->mne_version;
1338
1339                 /*
1340                  * Write a string with format "nid::instance" to
1341                  * lustre/<osc|mdc>/<target>-<osc|mdc>-<instance>/import.
1342                  */
1343
1344                 is_ost = entry->mne_type == LDD_F_SV_TYPE_OST;
1345                 memset(buf, 0, bufsz);
1346                 obdname = buf;
1347                 pos = 0;
1348
1349                 /* lustre-OST0001-osc-<instance #> */
1350                 strcpy(obdname, cld->cld_logname);
1351                 cname = strrchr(obdname, '-');
1352                 if (cname == NULL) {
1353                         CERROR("mgc %s: invalid logname %s\n",
1354                                mgc->obd_name, obdname);
1355                         break;
1356                 }
1357
1358                 pos = cname - obdname;
1359                 obdname[pos] = 0;
1360                 pos += sprintf(obdname + pos, "-%s%04x",
1361                                   is_ost ? "OST" : "MDT", entry->mne_index);
1362
1363                 cname = is_ost ? "osc" : "mdc",
1364                 pos += sprintf(obdname + pos, "-%s-%s", cname, inst);
1365                 lustre_cfg_bufs_reset(&bufs, obdname);
1366
1367                 /* find the obd by obdname */
1368                 obd = class_name2obd(obdname);
1369                 if (obd == NULL) {
1370                         CDEBUG(D_INFO, "mgc %s: cannot find obdname %s\n",
1371                                mgc->obd_name, obdname);
1372                         rc = 0;
1373                         /* this is a safe race, when the ost is starting up...*/
1374                         continue;
1375                 }
1376
1377                 /* osc.import = "connection=<Conn UUID>::<target instance>" */
1378                 ++pos;
1379                 params = buf + pos;
1380                 pos += sprintf(params, "%s.import=%s", cname, "connection=");
1381                 uuid = buf + pos;
1382
1383                 down_read(&obd->u.cli.cl_sem);
1384                 if (obd->u.cli.cl_import == NULL) {
1385                         /* client does not connect to the OST yet */
1386                         up_read(&obd->u.cli.cl_sem);
1387                         rc = 0;
1388                         continue;
1389                 }
1390
1391                 /* TODO: iterate all nids to find one */
1392                 /* find uuid by nid */
1393                 rc = client_import_find_conn(obd->u.cli.cl_import,
1394                                              entry->u.nids[0],
1395                                              (struct obd_uuid *)uuid);
1396                 up_read(&obd->u.cli.cl_sem);
1397                 if (rc < 0) {
1398                         CERROR("mgc: cannot find uuid by nid %s\n",
1399                                libcfs_nid2str(entry->u.nids[0]));
1400                         break;
1401                 }
1402
1403                 CDEBUG(D_INFO, "Find uuid %s by nid %s\n",
1404                        uuid, libcfs_nid2str(entry->u.nids[0]));
1405
1406                 pos += strlen(uuid);
1407                 pos += sprintf(buf + pos, "::%u", entry->mne_instance);
1408                 LASSERT(pos < bufsz);
1409
1410                 lustre_cfg_bufs_set_string(&bufs, 1, params);
1411
1412                 rc = -ENOMEM;
1413                 lcfg = lustre_cfg_new(LCFG_PARAM, &bufs);
1414                 if (lcfg == NULL) {
1415                         CERROR("mgc: cannot allocate memory\n");
1416                         break;
1417                 }
1418
1419                 CDEBUG(D_INFO, "ir apply logs "LPD64"/"LPD64" for %s -> %s\n",
1420                        prev_version, max_version, obdname, params);
1421
1422                 rc = class_process_config(lcfg);
1423                 lustre_cfg_free(lcfg);
1424                 if (rc)
1425                         CDEBUG(D_INFO, "process config for %s error %d\n",
1426                                obdname, rc);
1427
1428                 /* continue, even one with error */
1429         }
1430
1431         OBD_FREE(inst, CFS_PAGE_SIZE);
1432         RETURN(rc);
1433 }
1434
1435 /**
1436  * This function is called if this client was notified for target restarting
1437  * by the MGS. A CONFIG_READ RPC is going to send to fetch recovery logs.
1438  */
1439 static int mgc_process_recover_log(struct obd_device *obd,
1440                                    struct config_llog_data *cld)
1441 {
1442         struct ptlrpc_request *req = NULL;
1443         struct config_llog_instance *cfg = &cld->cld_cfg;
1444         struct mgs_config_body *body;
1445         struct mgs_config_res  *res;
1446         struct ptlrpc_bulk_desc *desc;
1447         cfs_page_t **pages;
1448         int nrpages;
1449         bool eof = true;
1450         bool mne_swab = false;
1451         int i;
1452         int ealen;
1453         int rc;
1454         ENTRY;
1455
1456         /* allocate buffer for bulk transfer.
1457          * if this is the first time for this mgs to read logs,
1458          * CONFIG_READ_NRPAGES_INIT will be used since it will read all logs
1459          * once; otherwise, it only reads increment of logs, this should be
1460          * small and CONFIG_READ_NRPAGES will be used.
1461          */
1462         nrpages = CONFIG_READ_NRPAGES;
1463         if (cfg->cfg_last_idx == 0) /* the first time */
1464                 nrpages = CONFIG_READ_NRPAGES_INIT;
1465
1466         OBD_ALLOC(pages, sizeof(*pages) * nrpages);
1467         if (pages == NULL)
1468                 GOTO(out, rc = -ENOMEM);
1469
1470         for (i = 0; i < nrpages; i++) {
1471                 pages[i] = cfs_alloc_page(CFS_ALLOC_STD);
1472                 if (pages[i] == NULL)
1473                         GOTO(out, rc = -ENOMEM);
1474         }
1475
1476 again:
1477         LASSERT(cld_is_recover(cld));
1478         LASSERT(mutex_is_locked(&cld->cld_lock));
1479         req = ptlrpc_request_alloc(class_exp2cliimp(cld->cld_mgcexp),
1480                                    &RQF_MGS_CONFIG_READ);
1481         if (req == NULL)
1482                 GOTO(out, rc = -ENOMEM);
1483
1484         rc = ptlrpc_request_pack(req, LUSTRE_MGS_VERSION, MGS_CONFIG_READ);
1485         if (rc)
1486                 GOTO(out, rc);
1487
1488         /* pack request */
1489         body = req_capsule_client_get(&req->rq_pill, &RMF_MGS_CONFIG_BODY);
1490         LASSERT(body != NULL);
1491         LASSERT(sizeof(body->mcb_name) > strlen(cld->cld_logname));
1492         if (strlcpy(body->mcb_name, cld->cld_logname, sizeof(body->mcb_name))
1493             >= sizeof(body->mcb_name))
1494                 GOTO(out, rc = -E2BIG);
1495         body->mcb_offset = cfg->cfg_last_idx + 1;
1496         body->mcb_type   = cld->cld_type;
1497         body->mcb_bits   = CFS_PAGE_SHIFT;
1498         body->mcb_units  = nrpages;
1499
1500         /* allocate bulk transfer descriptor */
1501         desc = ptlrpc_prep_bulk_imp(req, nrpages, 1, BULK_PUT_SINK,
1502                                     MGS_BULK_PORTAL);
1503         if (desc == NULL)
1504                 GOTO(out, rc = -ENOMEM);
1505
1506         for (i = 0; i < nrpages; i++)
1507                 ptlrpc_prep_bulk_page_pin(desc, pages[i], 0, CFS_PAGE_SIZE);
1508
1509         ptlrpc_request_set_replen(req);
1510         rc = ptlrpc_queue_wait(req);
1511         if (rc)
1512                 GOTO(out, rc);
1513
1514         res = req_capsule_server_get(&req->rq_pill, &RMF_MGS_CONFIG_RES);
1515         if (res->mcr_size < res->mcr_offset)
1516                 GOTO(out, rc = -EINVAL);
1517
1518         /* always update the index even though it might have errors with
1519          * handling the recover logs */
1520         cfg->cfg_last_idx = res->mcr_offset;
1521         eof = res->mcr_offset == res->mcr_size;
1522
1523         CDEBUG(D_INFO, "Latest version "LPD64", more %d.\n",
1524                res->mcr_offset, eof == false);
1525
1526         ealen = sptlrpc_cli_unwrap_bulk_read(req, req->rq_bulk, 0);
1527         if (ealen < 0)
1528                 GOTO(out, rc = ealen);
1529
1530         if (ealen > nrpages << CFS_PAGE_SHIFT)
1531                 GOTO(out, rc = -EINVAL);
1532
1533         if (ealen == 0) { /* no logs transferred */
1534                 if (!eof)
1535                         rc = -EINVAL;
1536                 GOTO(out, rc);
1537         }
1538
1539         mne_swab = !!ptlrpc_rep_need_swab(req);
1540 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 2, 50, 0)
1541         /* This import flag means the server did an extra swab of IR MNE
1542          * records (fixed in LU-1252), reverse it here if needed. LU-1644 */
1543         if (unlikely(req->rq_import->imp_need_mne_swab))
1544                 mne_swab = !mne_swab;
1545 #else
1546 #warning "LU-1644: Remove old OBD_CONNECT_MNE_SWAB fixup and imp_need_mne_swab"
1547 #endif
1548
1549         for (i = 0; i < nrpages && ealen > 0; i++) {
1550                 int rc2;
1551                 void *ptr;
1552
1553                 ptr = cfs_kmap(pages[i]);
1554                 rc2 = mgc_apply_recover_logs(obd, cld, res->mcr_offset, ptr,
1555                                              min_t(int, ealen, CFS_PAGE_SIZE),
1556                                              mne_swab);
1557                 cfs_kunmap(pages[i]);
1558                 if (rc2 < 0) {
1559                         CWARN("Process recover log %s error %d\n",
1560                               cld->cld_logname, rc2);
1561                         break;
1562                 }
1563
1564                 ealen -= CFS_PAGE_SIZE;
1565         }
1566
1567 out:
1568         if (req)
1569                 ptlrpc_req_finished(req);
1570
1571         if (rc == 0 && !eof)
1572                 goto again;
1573
1574         if (pages) {
1575                 for (i = 0; i < nrpages; i++) {
1576                         if (pages[i] == NULL)
1577                                 break;
1578                         cfs_free_page(pages[i]);
1579                 }
1580                 OBD_FREE(pages, sizeof(*pages) * nrpages);
1581         }
1582         return rc;
1583 }
1584
1585 #ifdef HAVE_LDISKFS_OSD
1586
1587 /*
1588  * XXX: mgc_copy_llog() does not support osd-based llogs yet
1589  */
1590
1591 /* identical to mgs_log_is_empty */
1592 static int mgc_llog_is_empty(struct obd_device *obd, struct llog_ctxt *ctxt,
1593                              char *name)
1594 {
1595         struct lvfs_run_ctxt     saved;
1596         struct llog_handle      *llh;
1597         int                      rc = 0;
1598
1599         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1600         rc = llog_open(NULL, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
1601         if (rc == 0) {
1602                 rc = llog_init_handle(NULL, llh, LLOG_F_IS_PLAIN, NULL);
1603                 if (rc == 0)
1604                         rc = llog_get_size(llh);
1605                 llog_close(NULL, llh);
1606         } else if (rc == -ENOENT) {
1607                 rc = 0;
1608         }
1609         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1610         /* header is record 1 */
1611         return (rc <= 1);
1612 }
1613
1614 /* Copy a remote log locally */
1615 static int mgc_copy_llog(struct obd_device *obd, struct llog_ctxt *rctxt,
1616                          struct llog_ctxt *lctxt, char *logname)
1617 {
1618         struct llog_handle *local_llh, *remote_llh;
1619         struct obd_uuid *uuid;
1620         char *temp_log;
1621         int rc, rc2;
1622         ENTRY;
1623
1624         /* Write new log to a temp name, then vfs_rename over logname
1625            upon successful completion. */
1626
1627         OBD_ALLOC(temp_log, strlen(logname) + 1);
1628         if (!temp_log)
1629                 RETURN(-ENOMEM);
1630         sprintf(temp_log, "%sT", logname);
1631
1632         /* Make sure there's no old temp log */
1633         rc = llog_erase(NULL, lctxt, NULL, temp_log);
1634         if (rc < 0 && rc != -ENOENT)
1635                 GOTO(out, rc);
1636
1637         /* open local log */
1638         rc = llog_open_create(NULL, lctxt, &local_llh, NULL, temp_log);
1639         if (rc)
1640                 GOTO(out, rc);
1641
1642         /* set the log header uuid for fun */
1643         OBD_ALLOC_PTR(uuid);
1644         obd_str2uuid(uuid, logname);
1645         rc = llog_init_handle(NULL, local_llh, LLOG_F_IS_PLAIN, uuid);
1646         OBD_FREE_PTR(uuid);
1647         if (rc)
1648                 GOTO(out_closel, rc);
1649
1650         /* open remote log */
1651         rc = llog_open(NULL, rctxt, &remote_llh, NULL, logname,
1652                        LLOG_OPEN_EXISTS);
1653         if (rc < 0) {
1654                 if (rc == -ENOENT)
1655                         rc = 0;
1656                 GOTO(out_closel, rc);
1657         }
1658
1659         rc = llog_init_handle(NULL, remote_llh, LLOG_F_IS_PLAIN, NULL);
1660         if (rc)
1661                 GOTO(out_closer, rc);
1662
1663         /* Copy remote log */
1664         rc = llog_process(NULL, remote_llh, llog_copy_handler,
1665                           (void *)local_llh, NULL);
1666
1667 out_closer:
1668         rc2 = llog_close(NULL, remote_llh);
1669         if (!rc)
1670                 rc = rc2;
1671 out_closel:
1672         rc2 = llog_close(NULL, local_llh);
1673         if (!rc)
1674                 rc = rc2;
1675
1676         /* We've copied the remote log to the local temp log, now
1677            replace the old local log with the temp log. */
1678         if (rc == 0) {
1679                 struct client_obd *cli = &obd->u.cli;
1680
1681                 LASSERT(cli);
1682                 LASSERT(cli->cl_mgc_configs_dir);
1683                 rc = lustre_rename(cli->cl_mgc_configs_dir, cli->cl_mgc_vfsmnt,
1684                                    temp_log, logname);
1685         }
1686         CDEBUG(D_MGC, "Copied remote log %s (%d)\n", logname, rc);
1687 out:
1688         if (rc)
1689                 CERROR("Failed to copy remote log %s (%d)\n", logname, rc);
1690         OBD_FREE(temp_log, strlen(logname) + 1);
1691         RETURN(rc);
1692 }
1693 #endif
1694
1695 /* local_only means it cannot get remote llogs */
1696 static int mgc_process_cfg_log(struct obd_device *mgc,
1697                                struct config_llog_data *cld,
1698                                int local_only)
1699 {
1700         struct llog_ctxt *ctxt, *lctxt = NULL;
1701 #ifdef HAVE_LDISKFS_OSD
1702         struct client_obd *cli = &mgc->u.cli;
1703 #endif
1704         struct lvfs_run_ctxt *saved_ctxt;
1705         struct lustre_sb_info *lsi = NULL;
1706         int rc = 0, must_pop = 0;
1707         bool sptlrpc_started = false;
1708
1709         ENTRY;
1710
1711         LASSERT(cld);
1712         LASSERT(mutex_is_locked(&cld->cld_lock));
1713
1714         /*
1715          * local copy of sptlrpc log is controlled elsewhere, don't try to
1716          * read it up here.
1717          */
1718         if (cld_is_sptlrpc(cld) && local_only)
1719                 RETURN(0);
1720
1721         if (cld->cld_cfg.cfg_sb)
1722                 lsi = s2lsi(cld->cld_cfg.cfg_sb);
1723
1724         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
1725         if (!ctxt) {
1726                 CERROR("missing llog context\n");
1727                 RETURN(-EINVAL);
1728         }
1729
1730         OBD_ALLOC_PTR(saved_ctxt);
1731         if (saved_ctxt == NULL)
1732                 RETURN(-ENOMEM);
1733
1734         lctxt = llog_get_context(mgc, LLOG_CONFIG_ORIG_CTXT);
1735
1736 #ifdef HAVE_LDISKFS_OSD
1737         /*
1738          * XXX: at the moment mgc_copy_llog() works with lvfs-based llogs
1739          */
1740         /* Copy the setup log locally if we can. Don't mess around if we're
1741            running an MGS though (logs are already local). */
1742         if (lctxt && lsi && IS_SERVER(lsi) &&
1743             (lsi->lsi_srv_mnt == cli->cl_mgc_vfsmnt) &&
1744             !IS_MGS(lsi) && lsi->lsi_srv_mnt) {
1745                 push_ctxt(saved_ctxt, &mgc->obd_lvfs_ctxt, NULL);
1746                 must_pop++;
1747                 if (!local_only)
1748                         /* Only try to copy log if we have the lock. */
1749                         rc = mgc_copy_llog(mgc, ctxt, lctxt, cld->cld_logname);
1750                 if (local_only || rc) {
1751                         if (mgc_llog_is_empty(mgc, lctxt, cld->cld_logname)) {
1752                                 LCONSOLE_ERROR_MSG(0x13a, "Failed to get MGS "
1753                                                    "log %s and no local copy."
1754                                                    "\n", cld->cld_logname);
1755                                 GOTO(out_pop, rc = -ENOTCONN);
1756                         }
1757                         CDEBUG(D_MGC, "Failed to get MGS log %s, using local "
1758                                "copy for now, will try to update later.\n",
1759                                cld->cld_logname);
1760                 }
1761                 /* Now, whether we copied or not, start using the local llog.
1762                    If we failed to copy, we'll start using whatever the old
1763                    log has. */
1764                 llog_ctxt_put(ctxt);
1765                 ctxt = lctxt;
1766                 lctxt = NULL;
1767         } else
1768 #endif
1769                 if (local_only) { /* no local log at client side */
1770                 GOTO(out_pop, rc = -EIO);
1771         }
1772
1773         if (cld_is_sptlrpc(cld)) {
1774                 sptlrpc_conf_log_update_begin(cld->cld_logname);
1775                 sptlrpc_started = true;
1776         }
1777
1778         /* logname and instance info should be the same, so use our
1779            copy of the instance for the update.  The cfg_last_idx will
1780            be updated here. */
1781         rc = class_config_parse_llog(NULL, ctxt, cld->cld_logname,
1782                                      &cld->cld_cfg);
1783         EXIT;
1784
1785 out_pop:
1786         llog_ctxt_put(ctxt);
1787         if (lctxt)
1788                 llog_ctxt_put(lctxt);
1789         if (must_pop)
1790                 pop_ctxt(saved_ctxt, &mgc->obd_lvfs_ctxt, NULL);
1791
1792         OBD_FREE_PTR(saved_ctxt);
1793         /*
1794          * update settings on existing OBDs. doing it inside
1795          * of llog_process_lock so no device is attaching/detaching
1796          * in parallel.
1797          * the logname must be <fsname>-sptlrpc
1798          */
1799         if (sptlrpc_started) {
1800                 LASSERT(cld_is_sptlrpc(cld));
1801                 sptlrpc_conf_log_update_end(cld->cld_logname);
1802                 class_notify_sptlrpc_conf(cld->cld_logname,
1803                                           strlen(cld->cld_logname) -
1804                                           strlen("-sptlrpc"));
1805         }
1806
1807         RETURN(rc);
1808 }
1809
1810 /** Get a config log from the MGS and process it.
1811  * This func is called for both clients and servers.
1812  * Copy the log locally before parsing it if appropriate (non-MGS server)
1813  */
1814 int mgc_process_log(struct obd_device *mgc, struct config_llog_data *cld)
1815 {
1816         struct lustre_handle lockh = { 0 };
1817         __u64 flags = LDLM_FL_NO_LRU;
1818         int rc = 0, rcl;
1819         ENTRY;
1820
1821         LASSERT(cld);
1822
1823         /* I don't want multiple processes running process_log at once --
1824            sounds like badness.  It actually might be fine, as long as
1825            we're not trying to update from the same log
1826            simultaneously (in which case we should use a per-log sem.) */
1827         mutex_lock(&cld->cld_lock);
1828         if (cld->cld_stopping) {
1829                 mutex_unlock(&cld->cld_lock);
1830                 RETURN(0);
1831         }
1832
1833         OBD_FAIL_TIMEOUT(OBD_FAIL_MGC_PAUSE_PROCESS_LOG, 20);
1834
1835         CDEBUG(D_MGC, "Process log %s:%p from %d\n", cld->cld_logname,
1836                cld->cld_cfg.cfg_instance, cld->cld_cfg.cfg_last_idx + 1);
1837
1838         /* Get the cfg lock on the llog */
1839         rcl = mgc_enqueue(mgc->u.cli.cl_mgc_mgsexp, NULL, LDLM_PLAIN, NULL,
1840                           LCK_CR, &flags, NULL, NULL, NULL,
1841                           cld, 0, NULL, &lockh);
1842         if (rcl == 0) {
1843                 /* Get the cld, it will be released in mgc_blocking_ast. */
1844                 config_log_get(cld);
1845                 rc = ldlm_lock_set_data(&lockh, (void *)cld);
1846                 LASSERT(rc == 0);
1847         } else {
1848                 CDEBUG(D_MGC, "Can't get cfg lock: %d\n", rcl);
1849
1850                 /* mark cld_lostlock so that it will requeue
1851                  * after MGC becomes available. */
1852                 cld->cld_lostlock = 1;
1853                 /* Get extra reference, it will be put in requeue thread */
1854                 config_log_get(cld);
1855         }
1856
1857
1858         if (cld_is_recover(cld)) {
1859                 rc = 0; /* this is not a fatal error for recover log */
1860                 if (rcl == 0)
1861                         rc = mgc_process_recover_log(mgc, cld);
1862         } else {
1863                 rc = mgc_process_cfg_log(mgc, cld, rcl != 0);
1864         }
1865
1866         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
1867                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
1868
1869         mutex_unlock(&cld->cld_lock);
1870
1871         /* Now drop the lock so MGS can revoke it */
1872         if (!rcl) {
1873                 rcl = mgc_cancel(mgc->u.cli.cl_mgc_mgsexp, NULL,
1874                                  LCK_CR, &lockh);
1875                 if (rcl)
1876                         CERROR("Can't drop cfg lock: %d\n", rcl);
1877         }
1878
1879         RETURN(rc);
1880 }
1881
1882
1883 /** Called from lustre_process_log.
1884  * LCFG_LOG_START gets the config log from the MGS, processes it to start
1885  * any services, and adds it to the list logs to watch (follow).
1886  */
1887 static int mgc_process_config(struct obd_device *obd, obd_count len, void *buf)
1888 {
1889         struct lustre_cfg *lcfg = buf;
1890         struct config_llog_instance *cfg = NULL;
1891         char *logname;
1892         int rc = 0;
1893         ENTRY;
1894
1895         switch(lcfg->lcfg_command) {
1896         case LCFG_LOV_ADD_OBD: {
1897                 /* Overloading this cfg command: register a new target */
1898                 struct mgs_target_info *mti;
1899
1900                 if (LUSTRE_CFG_BUFLEN(lcfg, 1) !=
1901                     sizeof(struct mgs_target_info))
1902                         GOTO(out, rc = -EINVAL);
1903
1904                 mti = (struct mgs_target_info *)lustre_cfg_buf(lcfg, 1);
1905                 CDEBUG(D_MGC, "add_target %s %#x\n",
1906                        mti->mti_svname, mti->mti_flags);
1907                 rc = mgc_target_register(obd->u.cli.cl_mgc_mgsexp, mti);
1908                 break;
1909         }
1910         case LCFG_LOV_DEL_OBD:
1911                 /* Unregister has no meaning at the moment. */
1912                 CERROR("lov_del_obd unimplemented\n");
1913                 rc = -ENOSYS;
1914                 break;
1915         case LCFG_SPTLRPC_CONF: {
1916                 rc = sptlrpc_process_config(lcfg);
1917                 break;
1918         }
1919         case LCFG_LOG_START: {
1920                 struct config_llog_data *cld;
1921                 struct super_block *sb;
1922
1923                 logname = lustre_cfg_string(lcfg, 1);
1924                 cfg = (struct config_llog_instance *)lustre_cfg_buf(lcfg, 2);
1925                 sb = *(struct super_block **)lustre_cfg_buf(lcfg, 3);
1926
1927                 CDEBUG(D_MGC, "parse_log %s from %d\n", logname,
1928                        cfg->cfg_last_idx);
1929
1930                 /* We're only called through here on the initial mount */
1931                 rc = config_log_add(obd, logname, cfg, sb);
1932                 if (rc)
1933                         break;
1934                 cld = config_log_find(logname, cfg);
1935                 if (cld == NULL) {
1936                         rc = -ENOENT;
1937                         break;
1938                 }
1939
1940                 /* COMPAT_146 */
1941                 /* FIXME only set this for old logs!  Right now this forces
1942                    us to always skip the "inside markers" check */
1943                 cld->cld_cfg.cfg_flags |= CFG_F_COMPAT146;
1944
1945                 rc = mgc_process_log(obd, cld);
1946                 if (rc == 0 && cld->cld_recover != NULL) {
1947                         if (OCD_HAS_FLAG(&obd->u.cli.cl_import->
1948                                          imp_connect_data, IMP_RECOV)) {
1949                                 rc = mgc_process_log(obd, cld->cld_recover);
1950                         } else {
1951                                 struct config_llog_data *cir = cld->cld_recover;
1952                                 cld->cld_recover = NULL;
1953                                 config_log_put(cir);
1954                         }
1955                         if (rc)
1956                                 CERROR("Cannot process recover llog %d\n", rc);
1957                 }
1958                 config_log_put(cld);
1959
1960                 break;
1961         }
1962         case LCFG_LOG_END: {
1963                 logname = lustre_cfg_string(lcfg, 1);
1964
1965                 if (lcfg->lcfg_bufcount >= 2)
1966                         cfg = (struct config_llog_instance *)lustre_cfg_buf(
1967                                 lcfg, 2);
1968                 rc = config_log_end(logname, cfg);
1969                 break;
1970         }
1971         default: {
1972                 CERROR("Unknown command: %d\n", lcfg->lcfg_command);
1973                 GOTO(out, rc = -EINVAL);
1974
1975         }
1976         }
1977 out:
1978         RETURN(rc);
1979 }
1980
1981 struct obd_ops mgc_obd_ops = {
1982         .o_owner        = THIS_MODULE,
1983         .o_setup        = mgc_setup,
1984         .o_precleanup   = mgc_precleanup,
1985         .o_cleanup      = mgc_cleanup,
1986         .o_add_conn     = client_import_add_conn,
1987         .o_del_conn     = client_import_del_conn,
1988         .o_connect      = client_connect_import,
1989         .o_disconnect   = client_disconnect_export,
1990         //.o_enqueue      = mgc_enqueue,
1991         .o_cancel       = mgc_cancel,
1992         //.o_iocontrol    = mgc_iocontrol,
1993         .o_set_info_async = mgc_set_info_async,
1994         .o_get_info       = mgc_get_info,
1995         .o_import_event = mgc_import_event,
1996         .o_llog_init    = mgc_llog_init,
1997         .o_llog_finish  = mgc_llog_finish,
1998         .o_process_config = mgc_process_config,
1999 };
2000
2001 int __init mgc_init(void)
2002 {
2003         return class_register_type(&mgc_obd_ops, NULL, NULL,
2004                                    LUSTRE_MGC_NAME, NULL);
2005 }
2006
2007 #ifdef __KERNEL__
2008 static void /*__exit*/ mgc_exit(void)
2009 {
2010         class_unregister_type(LUSTRE_MGC_NAME);
2011 }
2012
2013 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
2014 MODULE_DESCRIPTION("Lustre Management Client");
2015 MODULE_LICENSE("GPL");
2016
2017 module_init(mgc_init);
2018 module_exit(mgc_exit);
2019 #endif