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[fs/lustre-release.git] / 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 = sprintf(inst, "%p", cfg->cfg_instance);
1264         } else {
1265                 LASSERT(IS_MDT(lsi));
1266                 rc = server_name2svname(lsi->lsi_svname, inst, NULL);
1267                 if (rc) {
1268                         OBD_FREE(inst, CFS_PAGE_SIZE);
1269                         RETURN(-EINVAL);
1270                 }
1271                 pos = strlen(inst);
1272         }
1273
1274         ++pos;
1275         buf   = inst + pos;
1276         bufsz = CFS_PAGE_SIZE - pos;
1277
1278         while (datalen > 0) {
1279                 int   entry_len = sizeof(*entry);
1280                 int   is_ost;
1281                 struct obd_device *obd;
1282                 char *obdname;
1283                 char *cname;
1284                 char *params;
1285                 char *uuid;
1286
1287                 rc = -EINVAL;
1288                 if (datalen < sizeof(*entry))
1289                         break;
1290
1291                 entry = (typeof(entry))(data + off);
1292
1293                 /* sanity check */
1294                 if (entry->mne_nid_type != 0) /* only support type 0 for ipv4 */
1295                         break;
1296                 if (entry->mne_nid_count == 0) /* at least one nid entry */
1297                         break;
1298                 if (entry->mne_nid_size != sizeof(lnet_nid_t))
1299                         break;
1300
1301                 entry_len += entry->mne_nid_count * entry->mne_nid_size;
1302                 if (datalen < entry_len) /* must have entry_len at least */
1303                         break;
1304
1305                 /* Keep this swab for normal mixed endian handling. LU-1644 */
1306                 if (mne_swab)
1307                         lustre_swab_mgs_nidtbl_entry(entry);
1308                 if (entry->mne_length > CFS_PAGE_SIZE) {
1309                         CERROR("MNE too large (%u)\n", entry->mne_length);
1310                         break;
1311                 }
1312
1313                 if (entry->mne_length < entry_len)
1314                         break;
1315
1316                 off     += entry->mne_length;
1317                 datalen -= entry->mne_length;
1318                 if (datalen < 0)
1319                         break;
1320
1321                 if (entry->mne_version > max_version) {
1322                         CERROR("entry index(%lld) is over max_index(%lld)\n",
1323                                entry->mne_version, max_version);
1324                         break;
1325                 }
1326
1327                 if (prev_version >= entry->mne_version) {
1328                         CERROR("index unsorted, prev %lld, now %lld\n",
1329                                prev_version, entry->mne_version);
1330                         break;
1331                 }
1332                 prev_version = entry->mne_version;
1333
1334                 /*
1335                  * Write a string with format "nid::instance" to
1336                  * lustre/<osc|mdc>/<target>-<osc|mdc>-<instance>/import.
1337                  */
1338
1339                 is_ost = entry->mne_type == LDD_F_SV_TYPE_OST;
1340                 memset(buf, 0, bufsz);
1341                 obdname = buf;
1342                 pos = 0;
1343
1344                 /* lustre-OST0001-osc-<instance #> */
1345                 strcpy(obdname, cld->cld_logname);
1346                 cname = strrchr(obdname, '-');
1347                 if (cname == NULL) {
1348                         CERROR("mgc %s: invalid logname %s\n",
1349                                mgc->obd_name, obdname);
1350                         break;
1351                 }
1352
1353                 pos = cname - obdname;
1354                 obdname[pos] = 0;
1355                 pos += sprintf(obdname + pos, "-%s%04x",
1356                                   is_ost ? "OST" : "MDT", entry->mne_index);
1357
1358                 cname = is_ost ? "osc" : "mdc",
1359                 pos += sprintf(obdname + pos, "-%s-%s", cname, inst);
1360                 lustre_cfg_bufs_reset(&bufs, obdname);
1361
1362                 /* find the obd by obdname */
1363                 obd = class_name2obd(obdname);
1364                 if (obd == NULL) {
1365                         CDEBUG(D_INFO, "mgc %s: cannot find obdname %s\n",
1366                                mgc->obd_name, obdname);
1367                         rc = 0;
1368                         /* this is a safe race, when the ost is starting up...*/
1369                         continue;
1370                 }
1371
1372                 /* osc.import = "connection=<Conn UUID>::<target instance>" */
1373                 ++pos;
1374                 params = buf + pos;
1375                 pos += sprintf(params, "%s.import=%s", cname, "connection=");
1376                 uuid = buf + pos;
1377
1378                 down_read(&obd->u.cli.cl_sem);
1379                 if (obd->u.cli.cl_import == NULL) {
1380                         /* client does not connect to the OST yet */
1381                         up_read(&obd->u.cli.cl_sem);
1382                         rc = 0;
1383                         continue;
1384                 }
1385
1386                 /* TODO: iterate all nids to find one */
1387                 /* find uuid by nid */
1388                 rc = client_import_find_conn(obd->u.cli.cl_import,
1389                                              entry->u.nids[0],
1390                                              (struct obd_uuid *)uuid);
1391                 up_read(&obd->u.cli.cl_sem);
1392                 if (rc < 0) {
1393                         CERROR("mgc: cannot find uuid by nid %s\n",
1394                                libcfs_nid2str(entry->u.nids[0]));
1395                         break;
1396                 }
1397
1398                 CDEBUG(D_INFO, "Find uuid %s by nid %s\n",
1399                        uuid, libcfs_nid2str(entry->u.nids[0]));
1400
1401                 pos += strlen(uuid);
1402                 pos += sprintf(buf + pos, "::%u", entry->mne_instance);
1403                 LASSERT(pos < bufsz);
1404
1405                 lustre_cfg_bufs_set_string(&bufs, 1, params);
1406
1407                 rc = -ENOMEM;
1408                 lcfg = lustre_cfg_new(LCFG_PARAM, &bufs);
1409                 if (lcfg == NULL) {
1410                         CERROR("mgc: cannot allocate memory\n");
1411                         break;
1412                 }
1413
1414                 CDEBUG(D_INFO, "ir apply logs "LPD64"/"LPD64" for %s -> %s\n",
1415                        prev_version, max_version, obdname, params);
1416
1417                 rc = class_process_config(lcfg);
1418                 lustre_cfg_free(lcfg);
1419                 if (rc)
1420                         CDEBUG(D_INFO, "process config for %s error %d\n",
1421                                obdname, rc);
1422
1423                 /* continue, even one with error */
1424         }
1425
1426         OBD_FREE(inst, CFS_PAGE_SIZE);
1427         RETURN(rc);
1428 }
1429
1430 /**
1431  * This function is called if this client was notified for target restarting
1432  * by the MGS. A CONFIG_READ RPC is going to send to fetch recovery logs.
1433  */
1434 static int mgc_process_recover_log(struct obd_device *obd,
1435                                    struct config_llog_data *cld)
1436 {
1437         struct ptlrpc_request *req = NULL;
1438         struct config_llog_instance *cfg = &cld->cld_cfg;
1439         struct mgs_config_body *body;
1440         struct mgs_config_res  *res;
1441         struct ptlrpc_bulk_desc *desc;
1442         cfs_page_t **pages;
1443         int nrpages;
1444         bool eof = true;
1445         bool mne_swab = false;
1446         int i;
1447         int ealen;
1448         int rc;
1449         ENTRY;
1450
1451         /* allocate buffer for bulk transfer.
1452          * if this is the first time for this mgs to read logs,
1453          * CONFIG_READ_NRPAGES_INIT will be used since it will read all logs
1454          * once; otherwise, it only reads increment of logs, this should be
1455          * small and CONFIG_READ_NRPAGES will be used.
1456          */
1457         nrpages = CONFIG_READ_NRPAGES;
1458         if (cfg->cfg_last_idx == 0) /* the first time */
1459                 nrpages = CONFIG_READ_NRPAGES_INIT;
1460
1461         OBD_ALLOC(pages, sizeof(*pages) * nrpages);
1462         if (pages == NULL)
1463                 GOTO(out, rc = -ENOMEM);
1464
1465         for (i = 0; i < nrpages; i++) {
1466                 pages[i] = cfs_alloc_page(CFS_ALLOC_STD);
1467                 if (pages[i] == NULL)
1468                         GOTO(out, rc = -ENOMEM);
1469         }
1470
1471 again:
1472         LASSERT(cld_is_recover(cld));
1473         LASSERT(mutex_is_locked(&cld->cld_lock));
1474         req = ptlrpc_request_alloc(class_exp2cliimp(cld->cld_mgcexp),
1475                                    &RQF_MGS_CONFIG_READ);
1476         if (req == NULL)
1477                 GOTO(out, rc = -ENOMEM);
1478
1479         rc = ptlrpc_request_pack(req, LUSTRE_MGS_VERSION, MGS_CONFIG_READ);
1480         if (rc)
1481                 GOTO(out, rc);
1482
1483         /* pack request */
1484         body = req_capsule_client_get(&req->rq_pill, &RMF_MGS_CONFIG_BODY);
1485         LASSERT(body != NULL);
1486         LASSERT(sizeof(body->mcb_name) > strlen(cld->cld_logname));
1487         strncpy(body->mcb_name, cld->cld_logname, sizeof(body->mcb_name));
1488         body->mcb_offset = cfg->cfg_last_idx + 1;
1489         body->mcb_type   = cld->cld_type;
1490         body->mcb_bits   = CFS_PAGE_SHIFT;
1491         body->mcb_units  = nrpages;
1492
1493         /* allocate bulk transfer descriptor */
1494         desc = ptlrpc_prep_bulk_imp(req, nrpages, BULK_PUT_SINK,
1495                                     MGS_BULK_PORTAL);
1496         if (desc == NULL)
1497                 GOTO(out, rc = -ENOMEM);
1498
1499         for (i = 0; i < nrpages; i++)
1500                 ptlrpc_prep_bulk_page_pin(desc, pages[i], 0, CFS_PAGE_SIZE);
1501
1502         ptlrpc_request_set_replen(req);
1503         rc = ptlrpc_queue_wait(req);
1504         if (rc)
1505                 GOTO(out, rc);
1506
1507         res = req_capsule_server_get(&req->rq_pill, &RMF_MGS_CONFIG_RES);
1508         if (res->mcr_size < res->mcr_offset)
1509                 GOTO(out, rc = -EINVAL);
1510
1511         /* always update the index even though it might have errors with
1512          * handling the recover logs */
1513         cfg->cfg_last_idx = res->mcr_offset;
1514         eof = res->mcr_offset == res->mcr_size;
1515
1516         CDEBUG(D_INFO, "Latest version "LPD64", more %d.\n",
1517                res->mcr_offset, eof == false);
1518
1519         ealen = sptlrpc_cli_unwrap_bulk_read(req, req->rq_bulk, 0);
1520         if (ealen < 0)
1521                 GOTO(out, rc = ealen);
1522
1523         if (ealen > nrpages << CFS_PAGE_SHIFT)
1524                 GOTO(out, rc = -EINVAL);
1525
1526         if (ealen == 0) { /* no logs transferred */
1527                 if (!eof)
1528                         rc = -EINVAL;
1529                 GOTO(out, rc);
1530         }
1531
1532         mne_swab = !!ptlrpc_rep_need_swab(req);
1533 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 2, 50, 0)
1534         /* This import flag means the server did an extra swab of IR MNE
1535          * records (fixed in LU-1252), reverse it here if needed. LU-1644 */
1536         if (unlikely(req->rq_import->imp_need_mne_swab))
1537                 mne_swab = !mne_swab;
1538 #else
1539 #warning "LU-1644: Remove old OBD_CONNECT_MNE_SWAB fixup and imp_need_mne_swab"
1540 #endif
1541
1542         for (i = 0; i < nrpages && ealen > 0; i++) {
1543                 int rc2;
1544                 void *ptr;
1545
1546                 ptr = cfs_kmap(pages[i]);
1547                 rc2 = mgc_apply_recover_logs(obd, cld, res->mcr_offset, ptr,
1548                                              min_t(int, ealen, CFS_PAGE_SIZE),
1549                                              mne_swab);
1550                 cfs_kunmap(pages[i]);
1551                 if (rc2 < 0) {
1552                         CWARN("Process recover log %s error %d\n",
1553                               cld->cld_logname, rc2);
1554                         break;
1555                 }
1556
1557                 ealen -= CFS_PAGE_SIZE;
1558         }
1559
1560 out:
1561         if (req)
1562                 ptlrpc_req_finished(req);
1563
1564         if (rc == 0 && !eof)
1565                 goto again;
1566
1567         if (pages) {
1568                 for (i = 0; i < nrpages; i++) {
1569                         if (pages[i] == NULL)
1570                                 break;
1571                         cfs_free_page(pages[i]);
1572                 }
1573                 OBD_FREE(pages, sizeof(*pages) * nrpages);
1574         }
1575         return rc;
1576 }
1577
1578 #ifdef HAVE_LDISKFS_OSD
1579
1580 /*
1581  * XXX: mgc_copy_llog() does not support osd-based llogs yet
1582  */
1583
1584 /* identical to mgs_log_is_empty */
1585 static int mgc_llog_is_empty(struct obd_device *obd, struct llog_ctxt *ctxt,
1586                              char *name)
1587 {
1588         struct lvfs_run_ctxt     saved;
1589         struct llog_handle      *llh;
1590         int                      rc = 0;
1591
1592         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1593         rc = llog_open(NULL, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
1594         if (rc == 0) {
1595                 llog_init_handle(NULL, llh, LLOG_F_IS_PLAIN, NULL);
1596                 rc = llog_get_size(llh);
1597                 llog_close(NULL, llh);
1598         } else if (rc == -ENOENT) {
1599                 rc = 0;
1600         }
1601         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
1602         /* header is record 1 */
1603         return (rc <= 1);
1604 }
1605
1606 /* Copy a remote log locally */
1607 static int mgc_copy_llog(struct obd_device *obd, struct llog_ctxt *rctxt,
1608                          struct llog_ctxt *lctxt, char *logname)
1609 {
1610         struct llog_handle *local_llh, *remote_llh;
1611         struct obd_uuid *uuid;
1612         char *temp_log;
1613         int rc, rc2;
1614         ENTRY;
1615
1616         /* Write new log to a temp name, then vfs_rename over logname
1617            upon successful completion. */
1618
1619         OBD_ALLOC(temp_log, strlen(logname) + 1);
1620         if (!temp_log)
1621                 RETURN(-ENOMEM);
1622         sprintf(temp_log, "%sT", logname);
1623
1624         /* Make sure there's no old temp log */
1625         rc = llog_erase(NULL, lctxt, NULL, temp_log);
1626         if (rc < 0 && rc != -ENOENT)
1627                 GOTO(out, rc);
1628
1629         /* open local log */
1630         rc = llog_open_create(NULL, lctxt, &local_llh, NULL, temp_log);
1631         if (rc)
1632                 GOTO(out, rc);
1633
1634         /* set the log header uuid for fun */
1635         OBD_ALLOC_PTR(uuid);
1636         obd_str2uuid(uuid, logname);
1637         rc = llog_init_handle(NULL, local_llh, LLOG_F_IS_PLAIN, uuid);
1638         OBD_FREE_PTR(uuid);
1639         if (rc)
1640                 GOTO(out_closel, rc);
1641
1642         /* open remote log */
1643         rc = llog_open(NULL, rctxt, &remote_llh, NULL, logname,
1644                        LLOG_OPEN_EXISTS);
1645         if (rc < 0) {
1646                 if (rc == -ENOENT)
1647                         rc = 0;
1648                 GOTO(out_closel, rc);
1649         }
1650
1651         rc = llog_init_handle(NULL, remote_llh, LLOG_F_IS_PLAIN, NULL);
1652         if (rc)
1653                 GOTO(out_closer, rc);
1654
1655         /* Copy remote log */
1656         rc = llog_process(NULL, remote_llh, llog_copy_handler,
1657                           (void *)local_llh, NULL);
1658
1659 out_closer:
1660         rc2 = llog_close(NULL, remote_llh);
1661         if (!rc)
1662                 rc = rc2;
1663 out_closel:
1664         rc2 = llog_close(NULL, local_llh);
1665         if (!rc)
1666                 rc = rc2;
1667
1668         /* We've copied the remote log to the local temp log, now
1669            replace the old local log with the temp log. */
1670         if (rc == 0) {
1671                 struct client_obd *cli = &obd->u.cli;
1672
1673                 LASSERT(cli);
1674                 LASSERT(cli->cl_mgc_configs_dir);
1675                 rc = lustre_rename(cli->cl_mgc_configs_dir, cli->cl_mgc_vfsmnt,
1676                                    temp_log, logname);
1677         }
1678         CDEBUG(D_MGC, "Copied remote log %s (%d)\n", logname, rc);
1679 out:
1680         if (rc)
1681                 CERROR("Failed to copy remote log %s (%d)\n", logname, rc);
1682         OBD_FREE(temp_log, strlen(logname) + 1);
1683         RETURN(rc);
1684 }
1685 #endif
1686
1687 /* local_only means it cannot get remote llogs */
1688 static int mgc_process_cfg_log(struct obd_device *mgc,
1689                                struct config_llog_data *cld,
1690                                int local_only)
1691 {
1692         struct llog_ctxt *ctxt, *lctxt = NULL;
1693 #ifdef HAVE_LDISKFS_OSD
1694         struct client_obd *cli = &mgc->u.cli;
1695 #endif
1696         struct lvfs_run_ctxt *saved_ctxt;
1697         struct lustre_sb_info *lsi = NULL;
1698         int rc = 0, must_pop = 0;
1699         bool sptlrpc_started = false;
1700
1701         ENTRY;
1702
1703         LASSERT(cld);
1704         LASSERT(mutex_is_locked(&cld->cld_lock));
1705
1706         /*
1707          * local copy of sptlrpc log is controlled elsewhere, don't try to
1708          * read it up here.
1709          */
1710         if (cld_is_sptlrpc(cld) && local_only)
1711                 RETURN(0);
1712
1713         if (cld->cld_cfg.cfg_sb)
1714                 lsi = s2lsi(cld->cld_cfg.cfg_sb);
1715
1716         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
1717         if (!ctxt) {
1718                 CERROR("missing llog context\n");
1719                 RETURN(-EINVAL);
1720         }
1721
1722         OBD_ALLOC_PTR(saved_ctxt);
1723         if (saved_ctxt == NULL)
1724                 RETURN(-ENOMEM);
1725
1726         lctxt = llog_get_context(mgc, LLOG_CONFIG_ORIG_CTXT);
1727
1728 #ifdef HAVE_LDISKFS_OSD
1729         /*
1730          * XXX: at the moment mgc_copy_llog() works with lvfs-based llogs
1731          */
1732         /* Copy the setup log locally if we can. Don't mess around if we're
1733            running an MGS though (logs are already local). */
1734         if (lctxt && lsi && IS_SERVER(lsi) &&
1735             (lsi->lsi_srv_mnt == cli->cl_mgc_vfsmnt) &&
1736             !IS_MGS(lsi) && lsi->lsi_srv_mnt) {
1737                 push_ctxt(saved_ctxt, &mgc->obd_lvfs_ctxt, NULL);
1738                 must_pop++;
1739                 if (!local_only)
1740                         /* Only try to copy log if we have the lock. */
1741                         rc = mgc_copy_llog(mgc, ctxt, lctxt, cld->cld_logname);
1742                 if (local_only || rc) {
1743                         if (mgc_llog_is_empty(mgc, lctxt, cld->cld_logname)) {
1744                                 LCONSOLE_ERROR_MSG(0x13a, "Failed to get MGS "
1745                                                    "log %s and no local copy."
1746                                                    "\n", cld->cld_logname);
1747                                 GOTO(out_pop, rc = -ENOTCONN);
1748                         }
1749                         CDEBUG(D_MGC, "Failed to get MGS log %s, using local "
1750                                "copy for now, will try to update later.\n",
1751                                cld->cld_logname);
1752                 }
1753                 /* Now, whether we copied or not, start using the local llog.
1754                    If we failed to copy, we'll start using whatever the old
1755                    log has. */
1756                 llog_ctxt_put(ctxt);
1757                 ctxt = lctxt;
1758                 lctxt = NULL;
1759         } else
1760 #endif
1761                 if (local_only) { /* no local log at client side */
1762                 GOTO(out_pop, rc = -EIO);
1763         }
1764
1765         if (cld_is_sptlrpc(cld)) {
1766                 sptlrpc_conf_log_update_begin(cld->cld_logname);
1767                 sptlrpc_started = true;
1768         }
1769
1770         /* logname and instance info should be the same, so use our
1771            copy of the instance for the update.  The cfg_last_idx will
1772            be updated here. */
1773         rc = class_config_parse_llog(NULL, ctxt, cld->cld_logname,
1774                                      &cld->cld_cfg);
1775         EXIT;
1776
1777 out_pop:
1778         llog_ctxt_put(ctxt);
1779         if (lctxt)
1780                 llog_ctxt_put(lctxt);
1781         if (must_pop)
1782                 pop_ctxt(saved_ctxt, &mgc->obd_lvfs_ctxt, NULL);
1783
1784         OBD_FREE_PTR(saved_ctxt);
1785         /*
1786          * update settings on existing OBDs. doing it inside
1787          * of llog_process_lock so no device is attaching/detaching
1788          * in parallel.
1789          * the logname must be <fsname>-sptlrpc
1790          */
1791         if (sptlrpc_started) {
1792                 LASSERT(cld_is_sptlrpc(cld));
1793                 sptlrpc_conf_log_update_end(cld->cld_logname);
1794                 class_notify_sptlrpc_conf(cld->cld_logname,
1795                                           strlen(cld->cld_logname) -
1796                                           strlen("-sptlrpc"));
1797         }
1798
1799         RETURN(rc);
1800 }
1801
1802 /** Get a config log from the MGS and process it.
1803  * This func is called for both clients and servers.
1804  * Copy the log locally before parsing it if appropriate (non-MGS server)
1805  */
1806 int mgc_process_log(struct obd_device *mgc, struct config_llog_data *cld)
1807 {
1808         struct lustre_handle lockh = { 0 };
1809         __u64 flags = LDLM_FL_NO_LRU;
1810         int rc = 0, rcl;
1811         ENTRY;
1812
1813         LASSERT(cld);
1814
1815         /* I don't want multiple processes running process_log at once --
1816            sounds like badness.  It actually might be fine, as long as
1817            we're not trying to update from the same log
1818            simultaneously (in which case we should use a per-log sem.) */
1819         mutex_lock(&cld->cld_lock);
1820         if (cld->cld_stopping) {
1821                 mutex_unlock(&cld->cld_lock);
1822                 RETURN(0);
1823         }
1824
1825         OBD_FAIL_TIMEOUT(OBD_FAIL_MGC_PAUSE_PROCESS_LOG, 20);
1826
1827         CDEBUG(D_MGC, "Process log %s:%p from %d\n", cld->cld_logname,
1828                cld->cld_cfg.cfg_instance, cld->cld_cfg.cfg_last_idx + 1);
1829
1830         /* Get the cfg lock on the llog */
1831         rcl = mgc_enqueue(mgc->u.cli.cl_mgc_mgsexp, NULL, LDLM_PLAIN, NULL,
1832                           LCK_CR, &flags, NULL, NULL, NULL,
1833                           cld, 0, NULL, &lockh);
1834         if (rcl == 0) {
1835                 /* Get the cld, it will be released in mgc_blocking_ast. */
1836                 config_log_get(cld);
1837                 rc = ldlm_lock_set_data(&lockh, (void *)cld);
1838                 LASSERT(rc == 0);
1839         } else {
1840                 CDEBUG(D_MGC, "Can't get cfg lock: %d\n", rcl);
1841
1842                 /* mark cld_lostlock so that it will requeue
1843                  * after MGC becomes available. */
1844                 cld->cld_lostlock = 1;
1845                 /* Get extra reference, it will be put in requeue thread */
1846                 config_log_get(cld);
1847         }
1848
1849
1850         if (cld_is_recover(cld)) {
1851                 rc = 0; /* this is not a fatal error for recover log */
1852                 if (rcl == 0)
1853                         rc = mgc_process_recover_log(mgc, cld);
1854         } else {
1855                 rc = mgc_process_cfg_log(mgc, cld, rcl != 0);
1856         }
1857
1858         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
1859                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
1860
1861         mutex_unlock(&cld->cld_lock);
1862
1863         /* Now drop the lock so MGS can revoke it */
1864         if (!rcl) {
1865                 rcl = mgc_cancel(mgc->u.cli.cl_mgc_mgsexp, NULL,
1866                                  LCK_CR, &lockh);
1867                 if (rcl)
1868                         CERROR("Can't drop cfg lock: %d\n", rcl);
1869         }
1870
1871         RETURN(rc);
1872 }
1873
1874
1875 /** Called from lustre_process_log.
1876  * LCFG_LOG_START gets the config log from the MGS, processes it to start
1877  * any services, and adds it to the list logs to watch (follow).
1878  */
1879 static int mgc_process_config(struct obd_device *obd, obd_count len, void *buf)
1880 {
1881         struct lustre_cfg *lcfg = buf;
1882         struct config_llog_instance *cfg = NULL;
1883         char *logname;
1884         int rc = 0;
1885         ENTRY;
1886
1887         switch(lcfg->lcfg_command) {
1888         case LCFG_LOV_ADD_OBD: {
1889                 /* Overloading this cfg command: register a new target */
1890                 struct mgs_target_info *mti;
1891
1892                 if (LUSTRE_CFG_BUFLEN(lcfg, 1) !=
1893                     sizeof(struct mgs_target_info))
1894                         GOTO(out, rc = -EINVAL);
1895
1896                 mti = (struct mgs_target_info *)lustre_cfg_buf(lcfg, 1);
1897                 CDEBUG(D_MGC, "add_target %s %#x\n",
1898                        mti->mti_svname, mti->mti_flags);
1899                 rc = mgc_target_register(obd->u.cli.cl_mgc_mgsexp, mti);
1900                 break;
1901         }
1902         case LCFG_LOV_DEL_OBD:
1903                 /* Unregister has no meaning at the moment. */
1904                 CERROR("lov_del_obd unimplemented\n");
1905                 rc = -ENOSYS;
1906                 break;
1907         case LCFG_SPTLRPC_CONF: {
1908                 rc = sptlrpc_process_config(lcfg);
1909                 break;
1910         }
1911         case LCFG_LOG_START: {
1912                 struct config_llog_data *cld;
1913                 struct super_block *sb;
1914
1915                 logname = lustre_cfg_string(lcfg, 1);
1916                 cfg = (struct config_llog_instance *)lustre_cfg_buf(lcfg, 2);
1917                 sb = *(struct super_block **)lustre_cfg_buf(lcfg, 3);
1918
1919                 CDEBUG(D_MGC, "parse_log %s from %d\n", logname,
1920                        cfg->cfg_last_idx);
1921
1922                 /* We're only called through here on the initial mount */
1923                 rc = config_log_add(obd, logname, cfg, sb);
1924                 if (rc)
1925                         break;
1926                 cld = config_log_find(logname, cfg);
1927                 if (cld == NULL) {
1928                         rc = -ENOENT;
1929                         break;
1930                 }
1931
1932                 /* COMPAT_146 */
1933                 /* FIXME only set this for old logs!  Right now this forces
1934                    us to always skip the "inside markers" check */
1935                 cld->cld_cfg.cfg_flags |= CFG_F_COMPAT146;
1936
1937                 rc = mgc_process_log(obd, cld);
1938                 if (rc == 0 && cld->cld_recover != NULL) {
1939                         if (OCD_HAS_FLAG(&obd->u.cli.cl_import->
1940                                          imp_connect_data, IMP_RECOV)) {
1941                                 rc = mgc_process_log(obd, cld->cld_recover);
1942                         } else {
1943                                 struct config_llog_data *cir = cld->cld_recover;
1944                                 cld->cld_recover = NULL;
1945                                 config_log_put(cir);
1946                         }
1947                         if (rc)
1948                                 CERROR("Cannot process recover llog %d\n", rc);
1949                 }
1950                 config_log_put(cld);
1951
1952                 break;
1953         }
1954         case LCFG_LOG_END: {
1955                 logname = lustre_cfg_string(lcfg, 1);
1956
1957                 if (lcfg->lcfg_bufcount >= 2)
1958                         cfg = (struct config_llog_instance *)lustre_cfg_buf(
1959                                 lcfg, 2);
1960                 rc = config_log_end(logname, cfg);
1961                 break;
1962         }
1963         default: {
1964                 CERROR("Unknown command: %d\n", lcfg->lcfg_command);
1965                 GOTO(out, rc = -EINVAL);
1966
1967         }
1968         }
1969 out:
1970         RETURN(rc);
1971 }
1972
1973 struct obd_ops mgc_obd_ops = {
1974         .o_owner        = THIS_MODULE,
1975         .o_setup        = mgc_setup,
1976         .o_precleanup   = mgc_precleanup,
1977         .o_cleanup      = mgc_cleanup,
1978         .o_add_conn     = client_import_add_conn,
1979         .o_del_conn     = client_import_del_conn,
1980         .o_connect      = client_connect_import,
1981         .o_disconnect   = client_disconnect_export,
1982         //.o_enqueue      = mgc_enqueue,
1983         .o_cancel       = mgc_cancel,
1984         //.o_iocontrol    = mgc_iocontrol,
1985         .o_set_info_async = mgc_set_info_async,
1986         .o_get_info       = mgc_get_info,
1987         .o_import_event = mgc_import_event,
1988         .o_llog_init    = mgc_llog_init,
1989         .o_llog_finish  = mgc_llog_finish,
1990         .o_process_config = mgc_process_config,
1991 };
1992
1993 int __init mgc_init(void)
1994 {
1995         return class_register_type(&mgc_obd_ops, NULL, NULL,
1996                                    LUSTRE_MGC_NAME, NULL);
1997 }
1998
1999 #ifdef __KERNEL__
2000 static void /*__exit*/ mgc_exit(void)
2001 {
2002         class_unregister_type(LUSTRE_MGC_NAME);
2003 }
2004
2005 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
2006 MODULE_DESCRIPTION("Lustre Management Client");
2007 MODULE_LICENSE("GPL");
2008
2009 module_init(mgc_init);
2010 module_exit(mgc_exit);
2011 #endif