lustre/mgc/mgc_request.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  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 #ifndef EXPORT_SYMTAB
  42 # define EXPORT_SYMTAB
  43 #endif
  44 #define DEBUG_SUBSYSTEM S_MGC
  45 #define D_MGC D_CONFIG /*|D_WARNING*/
  46
  47 #ifdef __KERNEL__
  48 # include <linux/module.h>
  49 # include <linux/pagemap.h>
  50 # include <linux/miscdevice.h>
  51 # include <linux/init.h>
  52 #else
  53 # include <liblustre.h>
  54 #endif
  55
  56 #include <obd_class.h>
  57 #include <lustre_dlm.h>
  58 #include <lprocfs_status.h>
  59 #include <lustre_log.h>
  60 #include <lustre_fsfilt.h>
  61 #include <lustre_disk.h>
  62 #include "mgc_internal.h"
  63
  64 static int mgc_name2resid(char *name, int len, struct ldlm_res_id *res_id)
  65 {
  66         __u64 resname = 0;
  67
  68         if (len > 8) {
  69                 CERROR("name too long: %s\n", name);
  70                 return -EINVAL;
  71         }
  72         if (len <= 0) {
  73                 CERROR("missing name: %s\n", name);
  74                 return -EINVAL;
  75         }
  76         memcpy(&resname, name, len);
  77
  78         memset(res_id, 0, sizeof(*res_id));
  79
  80         /* Always use the same endianness for the resid */
  81         res_id->name[0] = cpu_to_le64(resname);
  82         CDEBUG(D_MGC, "log %s to resid "LPX64"/"LPX64" (%.8s)\n", name,
  83                res_id->name[0], res_id->name[1], (char *)&res_id->name[0]);
  84         return 0;
  85 }
  86
  87 int mgc_fsname2resid(char *fsname, struct ldlm_res_id *res_id)
  88 {
  89         /* fsname is at most 8 chars long, maybe contain "-".
  90          * e.g. "lustre", "SUN-000" */
  91         return mgc_name2resid(fsname, strlen(fsname), res_id);
  92 }
  93 EXPORT_SYMBOL(mgc_fsname2resid);
  94
  95 int mgc_logname2resid(char *logname, struct ldlm_res_id *res_id)
  96 {
  97         char *name_end;
  98         int len;
  99
 100         /* logname consists of "fsname-nodetype".
 101          * e.g. "lustre-MDT0001", "SUN-000-client" */
 102         name_end = strrchr(logname, '-');
 103         LASSERT(name_end);
 104         len = name_end - logname;
 105         return mgc_name2resid(logname, len, res_id);
 106 }
 107
 108 /********************** config llog list **********************/
 109 static CFS_LIST_HEAD(config_llog_list);
 110 static spinlock_t       config_list_lock = SPIN_LOCK_UNLOCKED;
 111
 112 /* Take a reference to a config log */
 113 static int config_log_get(struct config_llog_data *cld)
 114 {
 115         ENTRY;
 116         if (cld->cld_stopping)
 117                 RETURN(1);
 118         atomic_inc(&cld->cld_refcount);
 119         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 120                atomic_read(&cld->cld_refcount));
 121         RETURN(0);
 122 }
 123
 124 /* Drop a reference to a config log.  When no longer referenced,
 125    we can free the config log data */
 126 static void config_log_put(struct config_llog_data *cld)
 127 {
 128         ENTRY;
 129
 130         CDEBUG(D_INFO, "log %s refs %d\n", cld->cld_logname,
 131                atomic_read(&cld->cld_refcount));
 132         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 133
 134         /* spinlock to make sure no item with 0 refcount in the list */
 135         spin_lock(&config_list_lock);
 136         if (unlikely(atomic_dec_and_test(&cld->cld_refcount))) {
 137                 list_del(&cld->cld_list_chain);
 138                 spin_unlock(&config_list_lock);
 139
 140                 CDEBUG(D_MGC, "dropping config log %s\n", cld->cld_logname);
 141
 142                 if (cld->cld_sptlrpc)
 143                         config_log_put(cld->cld_sptlrpc);
 144                 if (cld->cld_is_sptlrpc)
 145                         sptlrpc_conf_log_stop(cld->cld_logname);
 146
 147                 class_export_put(cld->cld_mgcexp);
 148                 OBD_FREE(cld->cld_logname, strlen(cld->cld_logname) + 1);
 149                 if (cld->cld_cfg.cfg_instance != NULL)
 150                         OBD_FREE(cld->cld_cfg.cfg_instance,
 151                                  strlen(cld->cld_cfg.cfg_instance) + 1);
 152                 OBD_FREE(cld, sizeof(*cld));
 153         } else {
 154                 spin_unlock(&config_list_lock);
 155         }
 156
 157         EXIT;
 158 }
 159
 160 /* Find a config log by name */
 161 static
 162 struct config_llog_data *config_log_find(char *logname,
 163                                          struct config_llog_instance *cfg)
 164 {
 165         struct config_llog_data *cld;
 166         char *logid = logname;
 167         int match_instance = 0;
 168         ENTRY;
 169
 170         if (cfg && cfg->cfg_instance) {
 171                 match_instance++;
 172                 logid = cfg->cfg_instance;
 173         }
 174         if (!logid) {
 175                 CERROR("No log specified\n");
 176                 RETURN(ERR_PTR(-EINVAL));
 177         }
 178
 179         spin_lock(&config_list_lock);
 180         list_for_each_entry(cld, &config_llog_list, cld_list_chain) {
 181                 if (match_instance && cld->cld_cfg.cfg_instance &&
 182                     strcmp(logid, cld->cld_cfg.cfg_instance) == 0)
 183                         goto out_found;
 184                 if (!match_instance &&
 185                     strcmp(logid, cld->cld_logname) == 0)
 186                         goto out_found;
 187         }
 188         spin_unlock(&config_list_lock);
 189
 190         CDEBUG(D_CONFIG, "can't get log %s\n", logid);
 191         RETURN(ERR_PTR(-ENOENT));
 192 out_found:
 193         atomic_inc(&cld->cld_refcount);
 194         spin_unlock(&config_list_lock);
 195         LASSERT(cld->cld_stopping == 0 || cld->cld_is_sptlrpc == 0);
 196         RETURN(cld);
 197 }
 198
 199 static
 200 struct config_llog_data *do_config_log_add(struct obd_device *obd,
 201                                            char *logname,
 202                                            unsigned int is_sptlrpc,
 203                                            struct config_llog_instance *cfg,
 204                                            struct super_block *sb)
 205 {
 206         struct config_llog_data *cld;
 207         int                      rc;
 208         ENTRY;
 209
 210         CDEBUG(D_MGC, "do adding config log %s:%s\n", logname,
 211                cfg ? cfg->cfg_instance : "NULL");
 212
 213         OBD_ALLOC(cld, sizeof(*cld));
 214         if (!cld)
 215                 RETURN(ERR_PTR(-ENOMEM));
 216         OBD_ALLOC(cld->cld_logname, strlen(logname) + 1);
 217         if (!cld->cld_logname) {
 218                 OBD_FREE(cld, sizeof(*cld));
 219                 RETURN(ERR_PTR(-ENOMEM));
 220         }
 221         strcpy(cld->cld_logname, logname);
 222         if (cfg)
 223                 cld->cld_cfg = *cfg;
 224         cld->cld_cfg.cfg_last_idx = 0;
 225         cld->cld_cfg.cfg_flags = 0;
 226         cld->cld_cfg.cfg_sb = sb;
 227         cld->cld_is_sptlrpc = is_sptlrpc;
 228         atomic_set(&cld->cld_refcount, 1);
 229
 230         /* Keep the mgc around until we are done */
 231         cld->cld_mgcexp = class_export_get(obd->obd_self_export);
 232
 233         if (cfg && cfg->cfg_instance != NULL) {
 234                 OBD_ALLOC(cld->cld_cfg.cfg_instance,
 235                           strlen(cfg->cfg_instance) + 1);
 236                 strcpy(cld->cld_cfg.cfg_instance, cfg->cfg_instance);
 237         }
 238
 239         if (is_sptlrpc) {
 240                 sptlrpc_conf_log_start(logname);
 241                 cld->cld_cfg.cfg_obdname = obd->obd_name;
 242         }
 243
 244         rc = mgc_logname2resid(logname, &cld->cld_resid);
 245
 246         spin_lock(&config_list_lock);
 247         list_add(&cld->cld_list_chain, &config_llog_list);
 248         spin_unlock(&config_list_lock);
 249
 250         if (rc) {
 251                 config_log_put(cld);
 252                 RETURN(ERR_PTR(rc));
 253         }
 254
 255         if (is_sptlrpc) {
 256                 rc = mgc_process_log(obd, cld);
 257                 if (rc)
 258                         CERROR("failed processing sptlrpc log: %d\n", rc);
 259         }
 260
 261         RETURN(cld);
 262 }
 263
 264 /**
 265  * Add this log to our list of active logs.
 266  * We have one active log per "mount" - client instance or servername.
 267  * Each instance may be at a different point in the log.
 268  */
 269 static int config_log_add(struct obd_device *obd, char *logname,
 270                           struct config_llog_instance *cfg,
 271                           struct super_block *sb)
 272 {
 273         struct config_llog_data *cld, *sptlrpc_cld;
 274         char                     seclogname[20];
 275         char                    *ptr;
 276         ENTRY;
 277
 278         CDEBUG(D_MGC, "adding config log %s:%s\n", logname, cfg->cfg_instance);
 279
 280         /*
 281          * for each regular log, the depended sptlrpc log name is
 282          * <fsname>-sptlrpc. multiple regular logs may share one sptlrpc log.
 283          */
 284         ptr = strrchr(logname, '-');
 285         if (ptr == NULL || ptr - logname > 8) {
 286                 CERROR("logname %s is too long\n", logname);
 287                 RETURN(-EINVAL);
 288         }
 289
 290         memcpy(seclogname, logname, ptr - logname);
 291         strcpy(seclogname + (ptr - logname), "-sptlrpc");
 292
 293         sptlrpc_cld = config_log_find(seclogname, NULL);
 294         if (IS_ERR(sptlrpc_cld)) {
 295                 sptlrpc_cld = do_config_log_add(obd, seclogname, 1, NULL, NULL);
 296                 if (IS_ERR(sptlrpc_cld)) {
 297                         CERROR("can't create sptlrpc log: %s\n", seclogname);
 298                         RETURN(PTR_ERR(sptlrpc_cld));
 299                 }
 300         }
 301
 302         cld = do_config_log_add(obd, logname, 0, cfg, sb);
 303         if (IS_ERR(cld)) {
 304                 CERROR("can't create log: %s\n", logname);
 305                 config_log_put(sptlrpc_cld);
 306                 RETURN(PTR_ERR(cld));
 307         }
 308
 309         cld->cld_sptlrpc = sptlrpc_cld;
 310
 311         RETURN(0);
 312 }
 313
 314 DECLARE_MUTEX(llog_process_lock);
 315
 316 /* Stop watching for updates on this log. */
 317 static int config_log_end(char *logname, struct config_llog_instance *cfg)
 318 {
 319         struct config_llog_data *cld, *cld_sptlrpc = NULL;
 320         int rc = 0;
 321         ENTRY;
 322
 323         cld = config_log_find(logname, cfg);
 324         if (IS_ERR(cld))
 325                 RETURN(PTR_ERR(cld));
 326
 327         down(&llog_process_lock);
 328         /*
 329          * if cld_stopping is set, it means we didn't start the log thus
 330          * not owning the start ref. this can happen after previous umount:
 331          * the cld still hanging there waiting for lock cancel, and we
 332          * remount again but failed in the middle and call log_end without
 333          * calling start_log.
 334          */
 335         if (unlikely(cld->cld_stopping)) {
 336                 up(&llog_process_lock);
 337                 /* drop the ref from the find */
 338                 config_log_put(cld);
 339                 RETURN(rc);
 340         }
 341
 342         cld->cld_stopping = 1;
 343         up(&llog_process_lock);
 344
 345         spin_lock(&config_list_lock);
 346         cld_sptlrpc = cld->cld_sptlrpc;
 347         cld->cld_sptlrpc = NULL;
 348         spin_unlock(&config_list_lock);
 349
 350         if (cld_sptlrpc)
 351                 config_log_put(cld_sptlrpc);
 352
 353         /* drop the ref from the find */
 354         config_log_put(cld);
 355         /* drop the start ref */
 356         config_log_put(cld);
 357
 358         CDEBUG(D_MGC, "end config log %s (%d)\n", logname ? logname : "client",
 359                rc);
 360         RETURN(rc);
 361 }
 362
 363 /* reenqueue any lost locks */
 364 #define RQ_RUNNING 0x1
 365 #define RQ_NOW     0x2
 366 #define RQ_LATER   0x4
 367 #define RQ_STOP    0x8
 368 static int rq_state = 0;
 369 static cfs_waitq_t rq_waitq;
 370
 371 static int mgc_requeue_add(struct config_llog_data *cld, int later);
 372
 373 static void do_requeue(struct config_llog_data *cld)
 374 {
 375         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 376
 377         if (cld->cld_mgcexp->exp_obd->u.cli.cl_conn_count != 0) {
 378                 CDEBUG(D_MGC, "updating log %s\n", cld->cld_logname);
 379                 mgc_process_log(cld->cld_mgcexp->exp_obd, cld);
 380         } else {
 381                 CDEBUG(D_MGC, "disconnecting, won't update log %s\n",
 382                        cld->cld_logname);
 383         }
 384
 385         /* Whether we enqueued again or not in mgc_process_log, we're done
 386          * with the ref from the old enqueue */
 387         config_log_put(cld);
 388 }
 389
 390 static int mgc_requeue_thread(void *data)
 391 {
 392         struct l_wait_info lwi_now, lwi_later;
 393         struct config_llog_data *cld, *cld_next, *cld_prev;
 394         char name[] = "ll_cfg_requeue";
 395         int rc = 0;
 396         ENTRY;
 397
 398         ptlrpc_daemonize(name);
 399
 400         CDEBUG(D_MGC, "Starting requeue thread\n");
 401
 402         lwi_later = LWI_TIMEOUT(60 * HZ, NULL, NULL);
 403         l_wait_event(rq_waitq, rq_state & (RQ_NOW | RQ_STOP), &lwi_later);
 404
 405         /* Keep trying failed locks periodically */
 406         spin_lock(&config_list_lock);
 407         while (rq_state & (RQ_NOW | RQ_LATER)) {
 408                 /* Any new or requeued lostlocks will change the state */
 409                 rq_state &= ~(RQ_NOW | RQ_LATER);
 410                 spin_unlock(&config_list_lock);
 411
 412                 /* Always wait a few seconds to allow the server who
 413                    caused the lock revocation to finish its setup, plus some
 414                    random so everyone doesn't try to reconnect at once. */
 415                 lwi_now = LWI_TIMEOUT(3 * HZ + (ll_rand() & 0xff) * (HZ / 100),
 416                                       NULL, NULL);
 417                 l_wait_event(rq_waitq, rq_state & RQ_STOP, &lwi_now);
 418
 419                 /*
 420                  * iterate & processing through the list. for each cld, process
 421                  * its depending sptlrpc cld firstly (if any) and then itself.
 422                  *
 423                  * it's guaranteed any item in the list must have
 424                  * reference > 0; and if cld_lostlock is set, at
 425                  * least one reference is taken by the previous enqueue.
 426                  *
 427                  * Note: releasing a cld might lead to itself and its depended
 428                  * sptlrpc cld be unlinked from the list. to safely iterate
 429                  * we need to take a reference on next cld before processing.
 430                  */
 431                 cld_prev = NULL;
 432
 433                 spin_lock(&config_list_lock);
 434                 list_for_each_entry_safe(cld, cld_next, &config_llog_list,
 435                                          cld_list_chain) {
 436                         if (cld->cld_list_chain.next != &config_llog_list)
 437                                 atomic_inc(&cld_next->cld_refcount);
 438
 439                         if (cld->cld_lostlock) {
 440                                 if (cld->cld_sptlrpc &&
 441                                     cld->cld_sptlrpc->cld_lostlock) {
 442                                         cld->cld_sptlrpc->cld_lostlock = 0;
 443
 444                                         spin_unlock(&config_list_lock);
 445                                         do_requeue(cld->cld_sptlrpc);
 446                                         spin_lock(&config_list_lock);
 447                                         LASSERT(cld->cld_lostlock);
 448                                 }
 449
 450                                 cld->cld_lostlock = 0;
 451
 452                                 spin_unlock(&config_list_lock);
 453                                 do_requeue(cld);
 454                                 spin_lock(&config_list_lock);
 455                         }
 456
 457
 458                         if (cld_prev) {
 459                                 spin_unlock(&config_list_lock);
 460                                 config_log_put(cld_prev);
 461                                 spin_lock(&config_list_lock);
 462                         }
 463
 464                         cld_prev = cld_next;
 465                 }
 466                 spin_unlock(&config_list_lock);
 467
 468                 /* Wait a bit to see if anyone else needs a requeue */
 469                 l_wait_event(rq_waitq, rq_state & (RQ_NOW | RQ_STOP),
 470                              &lwi_later);
 471                 spin_lock(&config_list_lock);
 472         }
 473         /* spinlock and while guarantee RQ_NOW and RQ_LATER are not set */
 474         rq_state &= ~RQ_RUNNING;
 475         spin_unlock(&config_list_lock);
 476
 477         CDEBUG(D_MGC, "Ending requeue thread\n");
 478         RETURN(rc);
 479 }
 480
 481 /* Add a cld to the list to requeue.  Start the requeue thread if needed.
 482    We are responsible for dropping the config log reference from here on out. */
 483 static int mgc_requeue_add(struct config_llog_data *cld, int later)
 484 {
 485         int rc = 0;
 486
 487         CDEBUG(D_INFO, "log %s: requeue (l=%d r=%d sp=%d st=%x)\n",
 488                cld->cld_logname, later, atomic_read(&cld->cld_refcount),
 489                cld->cld_stopping, rq_state);
 490         LASSERT(atomic_read(&cld->cld_refcount) > 0);
 491
 492         /* Hold lock for rq_state */
 493         spin_lock(&config_list_lock);
 494
 495         if (cld->cld_stopping || (rq_state & RQ_STOP)) {
 496                 cld->cld_lostlock = 0;
 497                 spin_unlock(&config_list_lock);
 498                 config_log_put(cld);
 499                 RETURN(0);
 500         }
 501
 502         cld->cld_lostlock = 1;
 503
 504         if (!(rq_state & RQ_RUNNING)) {
 505                 LASSERT(rq_state == 0);
 506                 rq_state = RQ_RUNNING | (later ? RQ_LATER : RQ_NOW);
 507                 spin_unlock(&config_list_lock);
 508                 rc = cfs_kernel_thread(mgc_requeue_thread, 0,
 509                                        CLONE_VM | CLONE_FILES);
 510                 if (rc < 0) {
 511                         CERROR("log %s: cannot start requeue thread (%d),"
 512                                "no more log updates!\n", cld->cld_logname, rc);
 513                         /* Drop the ref, since the rq thread won't */
 514                         cld->cld_lostlock = 0;
 515                         config_log_put(cld);
 516                         rq_state = 0;
 517                         RETURN(rc);
 518                 }
 519         } else {
 520                 rq_state |= later ? RQ_LATER : RQ_NOW;
 521                 spin_unlock(&config_list_lock);
 522                 cfs_waitq_signal(&rq_waitq);
 523         }
 524
 525         RETURN(0);
 526 }
 527
 528 /********************** class fns **********************/
 529
 530 static int mgc_fs_setup(struct obd_device *obd, struct super_block *sb,
 531                         struct vfsmount *mnt)
 532 {
 533         struct lvfs_run_ctxt saved;
 534         struct lustre_sb_info *lsi = s2lsi(sb);
 535         struct client_obd *cli = &obd->u.cli;
 536         struct dentry *dentry;
 537         char *label;
 538         int err = 0;
 539         ENTRY;
 540
 541         LASSERT(lsi);
 542         LASSERT(lsi->lsi_srv_mnt == mnt);
 543
 544         /* The mgc fs exclusion sem. Only one fs can be setup at a time. */
 545         down(&cli->cl_mgc_sem);
 546
 547         cleanup_group_info();
 548
 549         obd->obd_fsops = fsfilt_get_ops(MT_STR(lsi->lsi_ldd));
 550         if (IS_ERR(obd->obd_fsops)) {
 551                 up(&cli->cl_mgc_sem);
 552                 CERROR("No fstype %s rc=%ld\n", MT_STR(lsi->lsi_ldd),
 553                        PTR_ERR(obd->obd_fsops));
 554                 RETURN(PTR_ERR(obd->obd_fsops));
 555         }
 556
 557         cli->cl_mgc_vfsmnt = mnt;
 558         fsfilt_setup(obd, mnt->mnt_sb);
 559
 560         OBD_SET_CTXT_MAGIC(&obd->obd_lvfs_ctxt);
 561         obd->obd_lvfs_ctxt.pwdmnt = mnt;
 562         obd->obd_lvfs_ctxt.pwd = mnt->mnt_root;
 563         obd->obd_lvfs_ctxt.fs = get_ds();
 564
 565         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 566         dentry = lookup_one_len(MOUNT_CONFIGS_DIR, current->fs->pwd,
 567                                 strlen(MOUNT_CONFIGS_DIR));
 568         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 569         if (IS_ERR(dentry)) {
 570                 err = PTR_ERR(dentry);
 571                 CERROR("cannot lookup %s directory: rc = %d\n",
 572                        MOUNT_CONFIGS_DIR, err);
 573                 GOTO(err_ops, err);
 574         }
 575         cli->cl_mgc_configs_dir = dentry;
 576
 577         /* We take an obd ref to insure that we can't get to mgc_cleanup
 578            without calling mgc_fs_cleanup first. */
 579         class_incref(obd, "mgc_fs", obd);
 580
 581         label = fsfilt_get_label(obd, mnt->mnt_sb);
 582         if (label)
 583                 CDEBUG(D_MGC, "MGC using disk labelled=%s\n", label);
 584
 585         /* We keep the cl_mgc_sem until mgc_fs_cleanup */
 586         RETURN(0);
 587
 588 err_ops:
 589         fsfilt_put_ops(obd->obd_fsops);
 590         obd->obd_fsops = NULL;
 591         cli->cl_mgc_vfsmnt = NULL;
 592         up(&cli->cl_mgc_sem);
 593         RETURN(err);
 594 }
 595
 596 static int mgc_fs_cleanup(struct obd_device *obd)
 597 {
 598         struct client_obd *cli = &obd->u.cli;
 599         int rc = 0;
 600         ENTRY;
 601
 602         LASSERT(cli->cl_mgc_vfsmnt != NULL);
 603
 604         if (cli->cl_mgc_configs_dir != NULL) {
 605                 struct lvfs_run_ctxt saved;
 606                 push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 607                 l_dput(cli->cl_mgc_configs_dir);
 608                 cli->cl_mgc_configs_dir = NULL;
 609                 pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 610                 class_decref(obd, "mgc_fs", obd);
 611         }
 612
 613         cli->cl_mgc_vfsmnt = NULL;
 614         if (obd->obd_fsops)
 615                 fsfilt_put_ops(obd->obd_fsops);
 616
 617         up(&cli->cl_mgc_sem);
 618
 619         RETURN(rc);
 620 }
 621
 622 static atomic_t mgc_count = ATOMIC_INIT(0);
 623 static int mgc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 624 {
 625         int rc = 0;
 626         ENTRY;
 627
 628         switch (stage) {
 629         case OBD_CLEANUP_EARLY:
 630                 break;
 631         case OBD_CLEANUP_EXPORTS:
 632                 if (atomic_dec_and_test(&mgc_count)) {
 633                         /* Kick the requeue waitq - cld's should all be
 634                            stopping */
 635                         spin_lock(&config_list_lock);
 636                         rq_state |= RQ_STOP;
 637                         spin_unlock(&config_list_lock);
 638                         cfs_waitq_signal(&rq_waitq);
 639                 }
 640                 rc = obd_llog_finish(obd, 0);
 641                 if (rc != 0)
 642                         CERROR("failed to cleanup llogging subsystems\n");
 643                 break;
 644         }
 645         RETURN(rc);
 646 }
 647
 648 static int mgc_cleanup(struct obd_device *obd)
 649 {
 650         struct client_obd *cli = &obd->u.cli;
 651         int rc;
 652         ENTRY;
 653
 654         LASSERT(cli->cl_mgc_vfsmnt == NULL);
 655
 656         /* COMPAT_146 - old config logs may have added profiles we don't
 657            know about */
 658         if (obd->obd_type->typ_refcnt <= 1)
 659                 /* Only for the last mgc */
 660                 class_del_profiles();
 661
 662         lprocfs_obd_cleanup(obd);
 663         ptlrpcd_decref();
 664
 665         rc = client_obd_cleanup(obd);
 666         RETURN(rc);
 667 }
 668
 669 static int mgc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 670 {
 671         struct lprocfs_static_vars lvars;
 672         int rc;
 673         ENTRY;
 674
 675         ptlrpcd_addref();
 676
 677         rc = client_obd_setup(obd, lcfg);
 678         if (rc)
 679                 GOTO(err_decref, rc);
 680
 681         rc = obd_llog_init(obd, &obd->obd_olg, obd, 0, NULL, NULL);
 682         if (rc) {
 683                 CERROR("failed to setup llogging subsystems\n");
 684                 GOTO(err_cleanup, rc);
 685         }
 686
 687         lprocfs_mgc_init_vars(&lvars);
 688         lprocfs_obd_setup(obd, lvars.obd_vars);
 689         sptlrpc_lprocfs_cliobd_attach(obd);
 690
 691         spin_lock(&config_list_lock);
 692         atomic_inc(&mgc_count);
 693         if (atomic_read(&mgc_count) == 1) {
 694                 rq_state &= ~RQ_STOP;
 695                 cfs_waitq_init(&rq_waitq);
 696         }
 697         spin_unlock(&config_list_lock);
 698
 699         RETURN(rc);
 700
 701 err_cleanup:
 702         client_obd_cleanup(obd);
 703 err_decref:
 704         ptlrpcd_decref();
 705         RETURN(rc);
 706 }
 707
 708 /* based on ll_mdc_blocking_ast */
 709 static int mgc_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 710                             void *data, int flag)
 711 {
 712         struct lustre_handle lockh;
 713         struct config_llog_data *cld = (struct config_llog_data *)data;
 714         int rc = 0;
 715         ENTRY;
 716
 717         switch (flag) {
 718         case LDLM_CB_BLOCKING:
 719                 /* mgs wants the lock, give it up... */
 720                 LDLM_DEBUG(lock, "MGC blocking CB");
 721                 ldlm_lock2handle(lock, &lockh);
 722                 rc = ldlm_cli_cancel(&lockh);
 723                 break;
 724         case LDLM_CB_CANCELING: {
 725                 /* We've given up the lock, prepare ourselves to update. */
 726                 LDLM_DEBUG(lock, "MGC cancel CB");
 727
 728                 CDEBUG(D_MGC, "Lock res "LPX64" (%.8s)\n",
 729                        lock->l_resource->lr_name.name[0],
 730                        (char *)&lock->l_resource->lr_name.name[0]);
 731
 732                 if (!cld) {
 733                         CERROR("missing data, won't requeue\n");
 734                         break;
 735                 }
 736                 /* Are we done with this log? */
 737                 if (cld->cld_stopping) {
 738                         CDEBUG(D_MGC, "log %s: stopping, won't requeue\n",
 739                                cld->cld_logname);
 740                         config_log_put(cld);
 741                         break;
 742                 }
 743                 /* Make sure not to re-enqueue when the mgc is stopping
 744                    (we get called from client_disconnect_export) */
 745                 if (!lock->l_conn_export ||
 746                     !lock->l_conn_export->exp_obd->u.cli.cl_conn_count) {
 747                         CDEBUG(D_MGC, "log %s: disconnecting, won't requeue\n",
 748                                cld->cld_logname);
 749                         config_log_put(cld);
 750                         break;
 751                 }
 752                 /* Did we fail to get the lock? */
 753                 if (lock->l_req_mode != lock->l_granted_mode &&
 754                     !cld->cld_is_sptlrpc) {
 755                         CDEBUG(D_MGC, "log %s: original grant failed, will "
 756                                "requeue later\n", cld->cld_logname);
 757                         /* Try to re-enqueue later */
 758                         rc = mgc_requeue_add(cld, 1);
 759                         break;
 760                 }
 761                 /* Re-enqueue now */
 762                 rc = mgc_requeue_add(cld, 0);
 763                 break;
 764         }
 765         default:
 766                 LBUG();
 767         }
 768
 769
 770         if (rc) {
 771                 CERROR("%s CB failed %d:\n", flag == LDLM_CB_BLOCKING ?
 772                        "blocking" : "cancel", rc);
 773                 LDLM_ERROR(lock, "MGC ast");
 774         }
 775         RETURN(rc);
 776 }
 777
 778 /* Send parameter to MGS*/
 779 static int mgc_set_mgs_param(struct obd_export *exp,
 780                              struct mgs_send_param *msp)
 781 {
 782         struct ptlrpc_request *req;
 783         struct mgs_send_param *req_msp, *rep_msp;
 784         int size[] = { sizeof(struct ptlrpc_body), sizeof(*req_msp) };
 785         __u32 rep_size[] = { sizeof(struct ptlrpc_body), sizeof(*msp) };
 786         int rc;
 787         ENTRY;
 788
 789         req = ptlrpc_prep_req(class_exp2cliimp(exp), LUSTRE_MGS_VERSION,
 790                               MGS_SET_INFO, 2, size, NULL);
 791         if (!req)
 792                 RETURN(-ENOMEM);
 793
 794         req_msp = lustre_msg_buf(req->rq_reqmsg, REQ_REC_OFF, sizeof(*req_msp));
 795         if (!req_msp)
 796                 RETURN(-ENOMEM);
 797
 798         memcpy(req_msp, msp, sizeof(*req_msp));
 799         ptlrpc_req_set_repsize(req, 2, rep_size);
 800         rc = ptlrpc_queue_wait(req);
 801         if (!rc) {
 802                 rep_msp = lustre_swab_repbuf(req, REPLY_REC_OFF,
 803                                              sizeof(*rep_msp), NULL);
 804                 memcpy(msp, rep_msp, sizeof(*rep_msp));
 805         }
 806
 807         ptlrpc_req_finished(req);
 808
 809         RETURN(rc);
 810 }
 811
 812 /* Take a config lock so we can get cancel notifications */
 813 static int mgc_enqueue(struct obd_export *exp, struct lov_stripe_md *lsm,
 814                        __u32 type, ldlm_policy_data_t *policy, __u32 mode,
 815                        int *flags, void *bl_cb, void *cp_cb, void *gl_cb,
 816                        void *data, __u32 lvb_len, void *lvb_swabber,
 817                        struct lustre_handle *lockh)
 818 {
 819         struct config_llog_data *cld = (struct config_llog_data *)data;
 820         struct ldlm_enqueue_info einfo = { type, mode, mgc_blocking_ast,
 821                          ldlm_completion_ast, NULL, NULL, data};
 822
 823         int rc;
 824         ENTRY;
 825
 826         CDEBUG(D_MGC, "Enqueue for %s (res "LPX64")\n", cld->cld_logname,
 827                cld->cld_resid.name[0]);
 828
 829         /* We can only drop this config log ref when we drop the lock */
 830         if (config_log_get(cld))
 831                 RETURN(ELDLM_LOCK_ABORTED);
 832
 833         /* We need a callback for every lockholder, so don't try to
 834            ldlm_lock_match (see rev 1.1.2.11.2.47) */
 835
 836         rc = ldlm_cli_enqueue(exp, NULL, &einfo, &cld->cld_resid,
 837                               NULL, flags, NULL, 0, NULL, lockh, 0);
 838         /* A failed enqueue should still call the mgc_blocking_ast,
 839            where it will be requeued if needed ("grant failed"). */
 840
 841         RETURN(rc);
 842 }
 843
 844 static int mgc_cancel(struct obd_export *exp, struct lov_stripe_md *md,
 845                       __u32 mode, struct lustre_handle *lockh)
 846 {
 847         ENTRY;
 848
 849         ldlm_lock_decref(lockh, mode);
 850
 851         RETURN(0);
 852 }
 853
 854 #if 0
 855 static int mgc_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
 856                          void *karg, void *uarg)
 857 {
 858         struct obd_device *obd = exp->exp_obd;
 859         struct obd_ioctl_data *data = karg;
 860         struct llog_ctxt *ctxt;
 861         struct lvfs_run_ctxt saved;
 862         int rc;
 863         ENTRY;
 864
 865         if (!try_module_get(THIS_MODULE)) {
 866                 CERROR("Can't get module. Is it alive?");
 867                 return -EINVAL;
 868         }
 869         switch (cmd) {
 870         /* REPLicator context */
 871         case OBD_IOC_PARSE: {
 872                 CERROR("MGC parsing llog %s\n", data->ioc_inlbuf1);
 873                 ctxt = llog_get_context(exp->exp_obd, LLOG_CONFIG_REPL_CTXT);
 874                 rc = class_config_parse_llog(ctxt, data->ioc_inlbuf1, NULL);
 875                 GOTO(out, rc);
 876         }
 877 #ifdef __KERNEL__
 878         case OBD_IOC_LLOG_INFO:
 879         case OBD_IOC_LLOG_PRINT: {
 880                 ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
 881                 rc = llog_ioctl(ctxt, cmd, data);
 882
 883                 GOTO(out, rc);
 884         }
 885 #endif
 886         /* ORIGinator context */
 887         case OBD_IOC_DUMP_LOG: {
 888                 ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
 889                 push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 890                 rc = class_config_dump_llog(ctxt, data->ioc_inlbuf1, NULL);
 891                 pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
 892                 if (rc)
 893                         RETURN(rc);
 894
 895                 GOTO(out, rc);
 896         }
 897         default:
 898                 CERROR("mgc_ioctl(): unrecognised ioctl %#x\n", cmd);
 899                 GOTO(out, rc = -ENOTTY);
 900         }
 901 out:
 902         module_put(THIS_MODULE);
 903
 904         return rc;
 905 }
 906 #endif
 907
 908 /* Send target_reg message to MGS */
 909 static int mgc_target_register(struct obd_export *exp,
 910                                struct mgs_target_info *mti)
 911 {
 912         struct ptlrpc_request  *req;
 913         struct mgs_target_info *req_mti, *rep_mti;
 914         int                     rc;
 915         ENTRY;
 916
 917         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
 918                                         &RQF_MGS_TARGET_REG, LUSTRE_MGS_VERSION,
 919                                         MGS_TARGET_REG);
 920         if (req == NULL)
 921                 RETURN(-ENOMEM);
 922
 923         req_mti = req_capsule_client_get(&req->rq_pill, &RMF_MGS_TARGET_INFO);
 924         memcpy(req_mti, mti, sizeof(*req_mti));
 925
 926         ptlrpc_request_set_replen(req);
 927
 928         CDEBUG(D_MGC, "register %s\n", mti->mti_svname);
 929
 930         rc = ptlrpc_queue_wait(req);
 931         if (!rc) {
 932                 rep_mti = req_capsule_server_get(&req->rq_pill,
 933                                                  &RMF_MGS_TARGET_INFO);
 934                 memcpy(mti, rep_mti, sizeof(*rep_mti));
 935                 CDEBUG(D_MGC, "register %s got index = %d\n",
 936                        mti->mti_svname, mti->mti_stripe_index);
 937         }
 938         ptlrpc_req_finished(req);
 939
 940         RETURN(rc);
 941 }
 942
 943 int mgc_set_info_async(struct obd_export *exp, obd_count keylen,
 944                        void *key, obd_count vallen, void *val,
 945                        struct ptlrpc_request_set *set)
 946 {
 947         struct obd_import *imp = class_exp2cliimp(exp);
 948         int rc = -EINVAL;
 949         ENTRY;
 950
 951         /* Try to "recover" the initial connection; i.e. retry */
 952         if (KEY_IS(KEY_INIT_RECOV)) {
 953                 if (vallen != sizeof(int))
 954                         RETURN(-EINVAL);
 955                 spin_lock(&imp->imp_lock);
 956                 imp->imp_initial_recov = *(int *)val;
 957                 spin_unlock(&imp->imp_lock);
 958                 CDEBUG(D_HA, "%s: set imp_initial_recov = %d\n",
 959                        exp->exp_obd->obd_name, imp->imp_initial_recov);
 960                 RETURN(0);
 961         }
 962         /* Turn off initial_recov after we try all backup servers once */
 963         if (KEY_IS(KEY_INIT_RECOV_BACKUP)) {
 964                 int value;
 965                 if (vallen != sizeof(int))
 966                         RETURN(-EINVAL);
 967                 value = *(int *)val;
 968                 spin_lock(&imp->imp_lock);
 969                 imp->imp_initial_recov_bk = value > 0;
 970                 /* Even after the initial connection, give up all comms if
 971                    nobody answers the first time. */
 972                 imp->imp_recon_bk = 1;
 973                 spin_unlock(&imp->imp_lock);
 974                 CDEBUG(D_MGC, "InitRecov %s %d/%d:d%d:i%d:r%d:or%d:%s\n",
 975                        imp->imp_obd->obd_name, value, imp->imp_initial_recov,
 976                        imp->imp_deactive, imp->imp_invalid,
 977                        imp->imp_replayable, imp->imp_obd->obd_replayable,
 978                        ptlrpc_import_state_name(imp->imp_state));
 979                 /* Resurrect if we previously died */
 980                 if (imp->imp_invalid || value > 1)
 981                         ptlrpc_reconnect_import(imp);
 982                 RETURN(0);
 983         }
 984         /* FIXME move this to mgc_process_config */
 985         if (KEY_IS(KEY_REGISTER_TARGET)) {
 986                 struct mgs_target_info *mti;
 987                 if (vallen != sizeof(struct mgs_target_info))
 988                         RETURN(-EINVAL);
 989                 mti = (struct mgs_target_info *)val;
 990                 CDEBUG(D_MGC, "register_target %s %#x\n",
 991                        mti->mti_svname, mti->mti_flags);
 992                 rc =  mgc_target_register(exp, mti);
 993                 RETURN(rc);
 994         }
 995         if (KEY_IS(KEY_SET_FS)) {
 996                 struct super_block *sb = (struct super_block *)val;
 997                 struct lustre_sb_info *lsi;
 998                 if (vallen != sizeof(struct super_block))
 999                         RETURN(-EINVAL);
1000                 lsi = s2lsi(sb);
1001                 rc = mgc_fs_setup(exp->exp_obd, sb, lsi->lsi_srv_mnt);
1002                 if (rc) {
1003                         CERROR("set_fs got %d\n", rc);
1004                 }
1005                 RETURN(rc);
1006         }
1007         if (KEY_IS(KEY_CLEAR_FS)) {
1008                 if (vallen != 0)
1009                         RETURN(-EINVAL);
1010                 rc = mgc_fs_cleanup(exp->exp_obd);
1011                 if (rc) {
1012                         CERROR("clear_fs got %d\n", rc);
1013                 }
1014                 RETURN(rc);
1015         }
1016         if (KEY_IS(KEY_SET_INFO)) {
1017                 struct mgs_send_param *msp;
1018
1019                 msp = (struct mgs_send_param *)val;
1020                 rc =  mgc_set_mgs_param(exp, msp);
1021                 RETURN(rc);
1022         }
1023         if (KEY_IS(KEY_MGSSEC)) {
1024                 struct client_obd     *cli = &exp->exp_obd->u.cli;
1025                 struct sptlrpc_flavor  flvr;
1026
1027                 /*
1028                  * empty string means using current flavor, if which haven't
1029                  * been set yet, set it as null.
1030                  *
1031                  * if flavor has been set previously, check the asking flavor
1032                  * must match the existing one.
1033                  */
1034                 if (vallen == 0) {
1035                         if (cli->cl_flvr_mgc.sf_rpc != SPTLRPC_FLVR_INVALID)
1036                                 RETURN(0);
1037                         val = "null";
1038                         vallen = 4;
1039                 }
1040
1041                 rc = sptlrpc_parse_flavor(val, &flvr);
1042                 if (rc) {
1043                         CERROR("invalid sptlrpc flavor %s to MGS\n",
1044                                (char *) val);
1045                         RETURN(rc);
1046                 }
1047
1048                 /*
1049                  * caller already hold a mutex
1050                  */
1051                 if (cli->cl_flvr_mgc.sf_rpc == SPTLRPC_FLVR_INVALID) {
1052                         cli->cl_flvr_mgc = flvr;
1053                 } else if (memcmp(&cli->cl_flvr_mgc, &flvr,
1054                                   sizeof(flvr)) != 0) {
1055                         char    str[20];
1056
1057                         sptlrpc_flavor2name(&cli->cl_flvr_mgc,
1058                                             str, sizeof(str));
1059                         LCONSOLE_ERROR("asking sptlrpc flavor %s to MGS but "
1060                                        "currently %s is in use\n",
1061                                        (char *) val, str);
1062                         rc = -EPERM;
1063                 }
1064                 RETURN(rc);
1065         }
1066
1067         RETURN(rc);
1068 }
1069
1070 static int mgc_import_event(struct obd_device *obd,
1071                             struct obd_import *imp,
1072                             enum obd_import_event event)
1073 {
1074         int rc = 0;
1075
1076         LASSERT(imp->imp_obd == obd);
1077         CDEBUG(D_MGC, "import event %#x\n", event);
1078
1079         switch (event) {
1080         case IMP_EVENT_DISCON:
1081                 /* MGC imports should not wait for recovery */
1082                 break;
1083         case IMP_EVENT_INACTIVE:
1084                 break;
1085         case IMP_EVENT_INVALIDATE: {
1086                 struct ldlm_namespace *ns = obd->obd_namespace;
1087                 ldlm_namespace_cleanup(ns, LDLM_FL_LOCAL_ONLY);
1088                 break;
1089         }
1090         case IMP_EVENT_ACTIVE:
1091                 LCONSOLE_WARN("%s: Reactivating import\n", obd->obd_name);
1092                 /* Clearing obd_no_recov allows us to continue pinging */
1093                 obd->obd_no_recov = 0;
1094                 break;
1095         case IMP_EVENT_OCD:
1096                 break;
1097         default:
1098                 CERROR("Unknown import event %#x\n", event);
1099                 LBUG();
1100         }
1101         RETURN(rc);
1102 }
1103
1104 static int mgc_llog_init(struct obd_device *obd, struct obd_llog_group *olg,
1105                          struct obd_device *tgt, int count,
1106                          struct llog_catid *logid, struct obd_uuid *uuid)
1107 {
1108         struct llog_ctxt *ctxt;
1109         int rc;
1110         ENTRY;
1111
1112         LASSERT(olg == &obd->obd_olg);
1113
1114         rc = llog_setup(obd, olg, LLOG_CONFIG_ORIG_CTXT, tgt, 0, NULL,
1115                         &llog_lvfs_ops);
1116         if (rc)
1117                 RETURN(rc);
1118
1119         rc = llog_setup(obd, olg, LLOG_CONFIG_REPL_CTXT, tgt, 0, NULL,
1120                         &llog_client_ops);
1121         if (rc == 0) {
1122                 ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
1123                 if (!ctxt) {
1124                         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
1125                         if (ctxt)
1126                                 llog_cleanup(ctxt);
1127                         RETURN(-ENODEV);
1128                 }
1129                 llog_initiator_connect(ctxt);
1130                 llog_ctxt_put(ctxt);
1131         } else {
1132                 ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
1133                 if (ctxt)
1134                         llog_cleanup(ctxt);
1135         }
1136
1137         RETURN(rc);
1138 }
1139
1140 static int mgc_llog_finish(struct obd_device *obd, int count)
1141 {
1142         struct llog_ctxt *ctxt;
1143         int rc = 0, rc2 = 0;
1144         ENTRY;
1145
1146         ctxt = llog_get_context(obd, LLOG_CONFIG_REPL_CTXT);
1147         if (ctxt)
1148                 rc = llog_cleanup(ctxt);
1149
1150         ctxt = llog_get_context(obd, LLOG_CONFIG_ORIG_CTXT);
1151         if (ctxt)
1152                 rc2 = llog_cleanup(ctxt);
1153
1154         if (!rc)
1155                 rc = rc2;
1156
1157         RETURN(rc);
1158 }
1159
1160 /* identical to mgs_log_is_empty */
1161 static int mgc_llog_is_empty(struct obd_device *obd, struct llog_ctxt *ctxt,
1162                             char *name)
1163 {
1164         struct lvfs_run_ctxt saved;
1165         struct llog_handle *llh;
1166         int rc = 0;
1167
1168         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1169         rc = llog_create(ctxt, &llh, NULL, name);
1170         if (rc == 0) {
1171                 llog_init_handle(llh, LLOG_F_IS_PLAIN, NULL);
1172                 rc = llog_get_size(llh);
1173                 llog_close(llh);
1174         }
1175         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1176         /* header is record 1 */
1177         return(rc <= 1);
1178 }
1179
1180 static int mgc_copy_handler(struct llog_handle *llh, struct llog_rec_hdr *rec,
1181                             void *data)
1182 {
1183         struct llog_rec_hdr local_rec = *rec;
1184         struct llog_handle *local_llh = (struct llog_handle *)data;
1185         char *cfg_buf = (char*) (rec + 1);
1186         struct lustre_cfg *lcfg;
1187         int rc = 0;
1188         ENTRY;
1189
1190         /* Append all records */
1191         local_rec.lrh_len -= sizeof(*rec) + sizeof(struct llog_rec_tail);
1192         rc = llog_write_rec(local_llh, &local_rec, NULL, 0,
1193                             (void *)cfg_buf, -1);
1194
1195         lcfg = (struct lustre_cfg *)cfg_buf;
1196         CDEBUG(D_INFO, "idx=%d, rc=%d, len=%d, cmd %x %s %s\n",
1197                rec->lrh_index, rc, rec->lrh_len, lcfg->lcfg_command,
1198                lustre_cfg_string(lcfg, 0), lustre_cfg_string(lcfg, 1));
1199
1200         RETURN(rc);
1201 }
1202
1203 /* Copy a remote log locally */
1204 static int mgc_copy_llog(struct obd_device *obd, struct llog_ctxt *rctxt,
1205                          struct llog_ctxt *lctxt, char *logname)
1206 {
1207         struct llog_handle *local_llh, *remote_llh;
1208         struct obd_uuid *uuid;
1209         char *temp_log;
1210         int rc, rc2;
1211         ENTRY;
1212
1213         /* Write new log to a temp name, then vfs_rename over logname
1214            upon successful completion. */
1215
1216         OBD_ALLOC(temp_log, strlen(logname) + 1);
1217         if (!temp_log)
1218                 RETURN(-ENOMEM);
1219         sprintf(temp_log, "%sT", logname);
1220
1221         /* Make sure there's no old temp log */
1222         rc = llog_create(lctxt, &local_llh, NULL, temp_log);
1223         if (rc)
1224                 GOTO(out, rc);
1225         rc = llog_init_handle(local_llh, LLOG_F_IS_PLAIN, NULL);
1226         if (rc)
1227                 GOTO(out, rc);
1228         rc = llog_destroy(local_llh);
1229         llog_free_handle(local_llh);
1230         if (rc)
1231                 GOTO(out, rc);
1232
1233         /* open local log */
1234         rc = llog_create(lctxt, &local_llh, NULL, temp_log);
1235         if (rc)
1236                 GOTO(out, rc);
1237
1238         /* set the log header uuid for fun */
1239         OBD_ALLOC_PTR(uuid);
1240         obd_str2uuid(uuid, logname);
1241         rc = llog_init_handle(local_llh, LLOG_F_IS_PLAIN, uuid);
1242         OBD_FREE_PTR(uuid);
1243         if (rc)
1244                 GOTO(out_closel, rc);
1245
1246         /* open remote log */
1247         rc = llog_create(rctxt, &remote_llh, NULL, logname);
1248         if (rc)
1249                 GOTO(out_closel, rc);
1250         rc = llog_init_handle(remote_llh, LLOG_F_IS_PLAIN, NULL);
1251         if (rc)
1252                 GOTO(out_closer, rc);
1253
1254         /* Copy remote log */
1255         rc = llog_process(remote_llh, mgc_copy_handler,(void *)local_llh, NULL);
1256
1257 out_closer:
1258         rc2 = llog_close(remote_llh);
1259         if (!rc)
1260                 rc = rc2;
1261 out_closel:
1262         rc2 = llog_close(local_llh);
1263         if (!rc)
1264                 rc = rc2;
1265
1266         /* We've copied the remote log to the local temp log, now
1267            replace the old local log with the temp log. */
1268         if (!rc) {
1269                 struct client_obd *cli = &obd->u.cli;
1270                 LASSERT(cli);
1271                 LASSERT(cli->cl_mgc_configs_dir);
1272                 rc = lustre_rename(cli->cl_mgc_configs_dir, cli->cl_mgc_vfsmnt,
1273                                    temp_log, logname);
1274         }
1275         CDEBUG(D_MGC, "Copied remote log %s (%d)\n", logname, rc);
1276 out:
1277         if (rc)
1278                 CERROR("Failed to copy remote log %s (%d)\n", logname, rc);
1279         OBD_FREE(temp_log, strlen(logname) + 1);
1280         RETURN(rc);
1281 }
1282
1283 /* Get a config log from the MGS and process it.
1284    This func is called for both clients and servers. */
1285 int mgc_process_log(struct obd_device *mgc,
1286                     struct config_llog_data *cld)
1287 {
1288         struct llog_ctxt *ctxt, *lctxt;
1289         struct lustre_handle lockh;
1290         struct client_obd *cli = &mgc->u.cli;
1291         struct lvfs_run_ctxt saved;
1292         struct lustre_sb_info *lsi = NULL;
1293         int rc = 0, rcl, flags = 0, must_pop = 0;
1294         ENTRY;
1295
1296         LASSERT(cld);
1297
1298         /* I don't want mutliple processes running process_log at once --
1299            sounds like badness.  It actually might be fine, as long as
1300            we're not trying to update from the same log
1301            simultaneously (in which case we should use a per-log sem.) */
1302         down(&llog_process_lock);
1303
1304         if (cld->cld_stopping) {
1305                 up(&llog_process_lock);
1306                 RETURN(0);
1307         }
1308
1309         OBD_FAIL_TIMEOUT(OBD_FAIL_MGC_PAUSE_PROCESS_LOG, 20);
1310
1311         if (cld->cld_cfg.cfg_sb)
1312                 lsi = s2lsi(cld->cld_cfg.cfg_sb);
1313
1314         CDEBUG(D_MGC, "Process log %s:%s from %d\n", cld->cld_logname,
1315                cld->cld_cfg.cfg_instance, cld->cld_cfg.cfg_last_idx + 1);
1316
1317         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
1318         if (!ctxt) {
1319                 CERROR("missing llog context\n");
1320                 up(&llog_process_lock);
1321                 RETURN(-EINVAL);
1322         }
1323
1324         /* Get the cfg lock on the llog */
1325         rcl = mgc_enqueue(mgc->u.cli.cl_mgc_mgsexp, NULL, LDLM_PLAIN, NULL,
1326                           LCK_CR, &flags, NULL, NULL, NULL,
1327                           cld, 0, NULL, &lockh);
1328         if (rcl)
1329                 CDEBUG(D_MGC, "Can't get cfg lock: %d\n", rcl);
1330
1331         lctxt = llog_get_context(mgc, LLOG_CONFIG_ORIG_CTXT);
1332
1333         /*
1334          * local copy of sptlrpc log is controlled elsewhere, don't try to
1335          * read it up here.
1336          */
1337         if (rcl && cld->cld_is_sptlrpc)
1338                 goto out_pop;
1339
1340         /* Copy the setup log locally if we can. Don't mess around if we're
1341            running an MGS though (logs are already local). */
1342         if (lctxt && lsi && (lsi->lsi_flags & LSI_SERVER) &&
1343             (lsi->lsi_srv_mnt == cli->cl_mgc_vfsmnt) &&
1344             !IS_MGS(lsi->lsi_ldd)) {
1345                 push_ctxt(&saved, &mgc->obd_lvfs_ctxt, NULL);
1346                 must_pop++;
1347                 if (rcl == 0)
1348                         /* Only try to copy log if we have the lock. */
1349                         rc = mgc_copy_llog(mgc, ctxt, lctxt, cld->cld_logname);
1350                 if (rcl || rc) {
1351                         if (mgc_llog_is_empty(mgc, lctxt, cld->cld_logname)) {
1352                                 LCONSOLE_ERROR_MSG(0x13a, "Failed to get MGS "
1353                                                    "log %s and no local copy."
1354                                                    "\n", cld->cld_logname);
1355                                 GOTO(out_pop, rc = -ENOTCONN);
1356                         }
1357                         CDEBUG(D_MGC, "Failed to get MGS log %s, using local "
1358                                "copy for now, will try to update later.\n",
1359                                cld->cld_logname);
1360                 }
1361                 /* Now, whether we copied or not, start using the local llog.
1362                    If we failed to copy, we'll start using whatever the old
1363                    log has. */
1364                 llog_ctxt_put(ctxt);
1365                 ctxt = lctxt;
1366         }
1367
1368         if (cld->cld_is_sptlrpc)
1369                 sptlrpc_conf_log_update_begin(cld->cld_logname);
1370
1371         /* logname and instance info should be the same, so use our
1372            copy of the instance for the update.  The cfg_last_idx will
1373            be updated here. */
1374         rc = class_config_parse_llog(ctxt, cld->cld_logname, &cld->cld_cfg);
1375 out_pop:
1376         llog_ctxt_put(ctxt);
1377         if (ctxt != lctxt)
1378                 llog_ctxt_put(lctxt);
1379         if (must_pop)
1380                 pop_ctxt(&saved, &mgc->obd_lvfs_ctxt, NULL);
1381
1382         /*
1383          * update settings on existing OBDs. doing it inside
1384          * of llog_process_lock so no device is attaching/detaching
1385          * in parallel.
1386          * the logname must be <fsname>-sptlrpc
1387          */
1388         if (cld->cld_is_sptlrpc && rcl == 0) {
1389                 sptlrpc_conf_log_update_end(cld->cld_logname);
1390                 class_notify_sptlrpc_conf(cld->cld_logname,
1391                                           strlen(cld->cld_logname) -
1392                                           strlen("-sptlrpc"));
1393         }
1394
1395         /* Now drop the lock so MGS can revoke it */
1396         if (!rcl) {
1397                 rcl = mgc_cancel(mgc->u.cli.cl_mgc_mgsexp, NULL,
1398                                  LCK_CR, &lockh);
1399                 if (rcl)
1400                         CERROR("Can't drop cfg lock: %d\n", rcl);
1401         }
1402
1403         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
1404                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
1405
1406         up(&llog_process_lock);
1407
1408         RETURN(rc);
1409 }
1410
1411 static int mgc_process_config(struct obd_device *obd, obd_count len, void *buf)
1412 {
1413         struct lustre_cfg *lcfg = buf;
1414         int cmd;
1415         int rc = 0;
1416         ENTRY;
1417
1418         switch(cmd = lcfg->lcfg_command) {
1419         case LCFG_LOV_ADD_OBD: {
1420                 /* Add any new target, not just osts */
1421                 struct mgs_target_info *mti;
1422
1423                 if (LUSTRE_CFG_BUFLEN(lcfg, 1) !=
1424                     sizeof(struct mgs_target_info))
1425                         GOTO(out, rc = -EINVAL);
1426
1427                 mti = (struct mgs_target_info *)lustre_cfg_buf(lcfg, 1);
1428                 CDEBUG(D_MGC, "add_target %s %#x\n",
1429                        mti->mti_svname, mti->mti_flags);
1430                 rc = mgc_target_register(obd->u.cli.cl_mgc_mgsexp, mti);
1431                 break;
1432         }
1433         case LCFG_LOV_DEL_OBD:
1434                 /* Remove target from the fs? */
1435                 /* FIXME */
1436                 CERROR("lov_del_obd unimplemented\n");
1437                 rc = -ENOSYS;
1438                 break;
1439         case LCFG_SPTLRPC_CONF: {
1440                 rc = sptlrpc_process_config(lcfg);
1441                 break;
1442         }
1443         case LCFG_LOG_START: {
1444                 struct config_llog_data *cld;
1445                 struct config_llog_instance *cfg;
1446                 struct super_block *sb;
1447                 char *logname = lustre_cfg_string(lcfg, 1);
1448                 cfg = (struct config_llog_instance *)lustre_cfg_buf(lcfg, 2);
1449                 sb = *(struct super_block **)lustre_cfg_buf(lcfg, 3);
1450
1451                 CDEBUG(D_MGC, "parse_log %s from %d\n", logname,
1452                        cfg->cfg_last_idx);
1453
1454                 /* We're only called through here on the initial mount */
1455                 rc = config_log_add(obd, logname, cfg, sb);
1456                 if (rc)
1457                         break;
1458                 cld = config_log_find(logname, cfg);
1459                 if (IS_ERR(cld)) {
1460                         rc = PTR_ERR(cld);
1461                         break;
1462                 }
1463
1464                 /* COMPAT_146 */
1465                 /* FIXME only set this for old logs!  Right now this forces
1466                    us to always skip the "inside markers" check */
1467                 cld->cld_cfg.cfg_flags |= CFG_F_COMPAT146;
1468
1469                 rc = mgc_process_log(obd, cld);
1470                 config_log_put(cld);
1471
1472                 break;
1473         }
1474         case LCFG_LOG_END: {
1475                 struct config_llog_instance *cfg = NULL;
1476                 char *logname = lustre_cfg_string(lcfg, 1);
1477                 if (lcfg->lcfg_bufcount >= 2)
1478                         cfg = (struct config_llog_instance *)lustre_cfg_buf(
1479                                 lcfg, 2);
1480                 rc = config_log_end(logname, cfg);
1481                 break;
1482         }
1483         default: {
1484                 CERROR("Unknown command: %d\n", lcfg->lcfg_command);
1485                 GOTO(out, rc = -EINVAL);
1486
1487         }
1488         }
1489 out:
1490         RETURN(rc);
1491 }
1492
1493 struct obd_ops mgc_obd_ops = {
1494         .o_owner        = THIS_MODULE,
1495         .o_setup        = mgc_setup,
1496         .o_precleanup   = mgc_precleanup,
1497         .o_cleanup      = mgc_cleanup,
1498         .o_add_conn     = client_import_add_conn,
1499         .o_del_conn     = client_import_del_conn,
1500         .o_connect      = client_connect_import,
1501         .o_disconnect   = client_disconnect_export,
1502         //.o_enqueue      = mgc_enqueue,
1503         .o_cancel       = mgc_cancel,
1504         //.o_iocontrol    = mgc_iocontrol,
1505         .o_set_info_async = mgc_set_info_async,
1506         .o_import_event = mgc_import_event,
1507         .o_llog_init    = mgc_llog_init,
1508         .o_llog_finish  = mgc_llog_finish,
1509         .o_process_config = mgc_process_config,
1510 };
1511
1512 int __init mgc_init(void)
1513 {
1514         return class_register_type(&mgc_obd_ops, NULL, NULL,
1515                                    LUSTRE_MGC_NAME, NULL);
1516 }
1517
1518 #ifdef __KERNEL__
1519 static void /*__exit*/ mgc_exit(void)
1520 {
1521         class_unregister_type(LUSTRE_MGC_NAME);
1522 }
1523
1524 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
1525 MODULE_DESCRIPTION("Lustre Management Client");
1526 MODULE_LICENSE("GPL");
1527
1528 module_init(mgc_init);
1529 module_exit(mgc_exit);
1530 #endif