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1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  *  Copyright (c) 2002, 2003 Cluster File Systems, Inc.
5  *   Author: Mike Shaver <shaver@clusterfs.com>
6  *
7  *   This file is part of the Lustre file system, http://www.lustre.org
8  *   Lustre is a trademark of Cluster File Systems, Inc.
9  *
10  *   You may have signed or agreed to another license before downloading
11  *   this software.  If so, you are bound by the terms and conditions
12  *   of that agreement, and the following does not apply to you.  See the
13  *   LICENSE file included with this distribution for more information.
14  *
15  *   If you did not agree to a different license, then this copy of Lustre
16  *   is open source software; you can redistribute it and/or modify it
17  *   under the terms of version 2 of the GNU General Public License as
18  *   published by the Free Software Foundation.
19  *
20  *   In either case, Lustre is distributed in the hope that it will be
21  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
22  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  *   license text for more details.
24  */
25
26 #define DEBUG_SUBSYSTEM S_RPC
27 #ifndef __KERNEL__
28 # include <liblustre.h>
29 #endif
30
31 #include <obd_support.h>
32 #include <lustre_ha.h>
33 #include <lustre_net.h>
34 #include <lustre_import.h>
35 #include <lustre_export.h>
36 #include <obd.h>
37 #include <obd_class.h>
38
39 #include "ptlrpc_internal.h"
40
41 struct ptlrpc_connect_async_args {
42          __u64 pcaa_peer_committed;
43         int pcaa_initial_connect;
44 };
45
46 /* A CLOSED import should remain so. */
47 #define IMPORT_SET_STATE_NOLOCK(imp, state)                                    \
48 do {                                                                           \
49         if (imp->imp_state != LUSTRE_IMP_CLOSED) {                             \
50                CDEBUG(D_HA, "%p %s: changing import state from %s to %s\n",    \
51                       imp, obd2cli_tgt(imp->imp_obd),                          \
52                       ptlrpc_import_state_name(imp->imp_state),                \
53                       ptlrpc_import_state_name(state));                        \
54                imp->imp_state = state;                                         \
55         }                                                                      \
56 } while(0)
57
58 #define IMPORT_SET_STATE(imp, state)            \
59 do {                                            \
60         spin_lock(&imp->imp_lock);              \
61         IMPORT_SET_STATE_NOLOCK(imp, state);    \
62         spin_unlock(&imp->imp_lock);            \
63 } while(0)
64
65
66 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
67                                     void * data, int rc);
68 int ptlrpc_import_recovery_state_machine(struct obd_import *imp);
69
70 /* Only this function is allowed to change the import state when it is
71  * CLOSED. I would rather refcount the import and free it after
72  * disconnection like we do with exports. To do that, the client_obd
73  * will need to save the peer info somewhere other than in the import,
74  * though. */
75 int ptlrpc_init_import(struct obd_import *imp)
76 {
77         spin_lock(&imp->imp_lock);
78
79         imp->imp_generation++;
80         imp->imp_state =  LUSTRE_IMP_NEW;
81
82         spin_unlock(&imp->imp_lock);
83
84         return 0;
85 }
86 EXPORT_SYMBOL(ptlrpc_init_import);
87
88 #define UUID_STR "_UUID"
89 static void deuuidify(char *uuid, const char *prefix, char **uuid_start,
90                       int *uuid_len)
91 {
92         *uuid_start = !prefix || strncmp(uuid, prefix, strlen(prefix))
93                 ? uuid : uuid + strlen(prefix);
94
95         *uuid_len = strlen(*uuid_start);
96
97         if (*uuid_len < strlen(UUID_STR))
98                 return;
99
100         if (!strncmp(*uuid_start + *uuid_len - strlen(UUID_STR),
101                     UUID_STR, strlen(UUID_STR)))
102                 *uuid_len -= strlen(UUID_STR);
103 }
104
105 /* Returns true if import was FULL, false if import was already not
106  * connected.
107  * @imp - import to be disconnected
108  * @conn_cnt - connection count (epoch) of the request that timed out
109  *             and caused the disconnection.  In some cases, multiple
110  *             inflight requests can fail to a single target (e.g. OST
111  *             bulk requests) and if one has already caused a reconnection
112  *             (increasing the import->conn_cnt) the older failure should
113  *             not also cause a reconnection.  If zero it forces a reconnect.
114  */
115 int ptlrpc_set_import_discon(struct obd_import *imp, __u32 conn_cnt)
116 {
117         int rc = 0;
118
119         spin_lock(&imp->imp_lock);
120
121         if (imp->imp_state == LUSTRE_IMP_FULL &&
122             (conn_cnt == 0 || conn_cnt == imp->imp_conn_cnt)) {
123                 char *target_start;
124                 int   target_len;
125
126                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
127                           &target_start, &target_len);
128
129                 if (imp->imp_replayable) {
130                         LCONSOLE_WARN("%s: Connection to service %.*s via nid "
131                                "%s was lost; in progress operations using this "
132                                "service will wait for recovery to complete.\n",
133                                imp->imp_obd->obd_name, target_len, target_start,
134                                libcfs_nid2str(imp->imp_connection->c_peer.nid));
135                 } else {
136                         LCONSOLE_ERROR_MSG(0x166, "%s: Connection to service "
137                                            "%.*s via nid %s was lost; in progress"
138                                            "operations using this service will"
139                                            "fail.\n",
140                                            imp->imp_obd->obd_name,
141                                            target_len, target_start,
142                                  libcfs_nid2str(imp->imp_connection->c_peer.nid));
143                 }
144                 ptlrpc_deactivate_timeouts(imp);
145                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
146                 spin_unlock(&imp->imp_lock);
147     
148                 if (obd_dump_on_timeout)
149                         libcfs_debug_dumplog();
150
151                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_DISCON);
152                 rc = 1;
153         } else {
154                 spin_unlock(&imp->imp_lock);
155                 CDEBUG(D_HA, "%s: import %p already %s (conn %u, was %u): %s\n",
156                        imp->imp_client->cli_name, imp,
157                        (imp->imp_state == LUSTRE_IMP_FULL &&
158                         imp->imp_conn_cnt > conn_cnt) ?
159                        "reconnected" : "not connected", imp->imp_conn_cnt,
160                        conn_cnt, ptlrpc_import_state_name(imp->imp_state));
161         }
162
163         return rc;
164 }
165
166 /*
167  * This acts as a barrier; all existing requests are rejected, and
168  * no new requests will be accepted until the import is valid again.
169  */
170 void ptlrpc_deactivate_import(struct obd_import *imp)
171 {
172         ENTRY;
173
174         spin_lock(&imp->imp_lock);
175         if (imp->imp_invalid) {
176                 spin_unlock(&imp->imp_lock);
177                 EXIT;
178                 return;
179         }
180
181         CDEBUG(D_HA, "setting import %s INVALID\n", obd2cli_tgt(imp->imp_obd));
182         imp->imp_invalid = 1;
183         imp->imp_generation++;
184         spin_unlock(&imp->imp_lock);
185
186         ptlrpc_abort_inflight(imp);
187         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
188
189         EXIT;
190 }
191
192 /*
193  * This function will invalidate the import, if necessary, then block
194  * for all the RPC completions, and finally notify the obd to
195  * invalidate its state (ie cancel locks, clear pending requests,
196  * etc).
197  */
198 void ptlrpc_invalidate_import(struct obd_import *imp)
199 {
200         struct l_wait_info lwi;
201         int rc;
202
203         atomic_inc(&imp->imp_inval_count);
204
205         ptlrpc_deactivate_import(imp);
206
207         LASSERT(imp->imp_invalid);
208
209         /* wait for all requests to error out and call completion callbacks */
210         lwi = LWI_TIMEOUT_INTERVAL(cfs_timeout_cap(cfs_time_seconds(obd_timeout)), 
211                                    HZ, NULL, NULL);
212         rc = l_wait_event(imp->imp_recovery_waitq,
213                           (atomic_read(&imp->imp_inflight) == 0), &lwi);
214
215         if (rc)
216                 CDEBUG(D_HA, "%s: rc = %d waiting for callback (%d != 0)\n",
217                        obd2cli_tgt(imp->imp_obd), rc,
218                        atomic_read(&imp->imp_inflight));
219
220         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
221         sptlrpc_import_flush_all_ctx(imp);
222
223         atomic_dec(&imp->imp_inval_count);
224         cfs_waitq_signal(&imp->imp_recovery_waitq);
225 }
226
227 /* unset imp_invalid */
228 void ptlrpc_activate_import(struct obd_import *imp)
229 {
230         struct obd_device *obd = imp->imp_obd;
231
232         spin_lock(&imp->imp_lock);
233         imp->imp_invalid = 0;
234         ptlrpc_activate_timeouts(imp);
235         spin_unlock(&imp->imp_lock);
236         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
237 }
238
239 void ptlrpc_fail_import(struct obd_import *imp, __u32 conn_cnt)
240 {
241         ENTRY;
242
243         LASSERT(!imp->imp_dlm_fake);
244
245         if (ptlrpc_set_import_discon(imp, conn_cnt)) {
246                 if (!imp->imp_replayable) {
247                         CDEBUG(D_HA, "import %s@%s for %s not replayable, "
248                                "auto-deactivating\n",
249                                obd2cli_tgt(imp->imp_obd),
250                                imp->imp_connection->c_remote_uuid.uuid,
251                                imp->imp_obd->obd_name);
252                         ptlrpc_deactivate_import(imp);
253                 }
254
255                 CDEBUG(D_HA, "%s: waking up pinger\n",
256                        obd2cli_tgt(imp->imp_obd));
257
258                 spin_lock(&imp->imp_lock);
259                 imp->imp_force_verify = 1;
260                 spin_unlock(&imp->imp_lock);
261
262                 ptlrpc_pinger_wake_up();
263         }
264         EXIT;
265 }
266
267 static int import_select_connection(struct obd_import *imp)
268 {
269         struct obd_import_conn *imp_conn = NULL, *conn;
270         struct obd_export *dlmexp;
271         ENTRY;
272
273         spin_lock(&imp->imp_lock);
274
275         if (list_empty(&imp->imp_conn_list)) {
276                 CERROR("%s: no connections available\n",
277                         imp->imp_obd->obd_name);
278                 spin_unlock(&imp->imp_lock);
279                 RETURN(-EINVAL);
280         }
281
282         list_for_each_entry(conn, &imp->imp_conn_list, oic_item) {
283                 CDEBUG(D_HA, "%s: connect to NID %s last attempt "LPU64"\n",
284                        imp->imp_obd->obd_name,
285                        libcfs_nid2str(conn->oic_conn->c_peer.nid),
286                        conn->oic_last_attempt);
287                 /* Throttle the reconnect rate to once per RECONNECT_INTERVAL */
288                 if (cfs_time_before_64(conn->oic_last_attempt + 
289                                        RECONNECT_INTERVAL * HZ,
290                                        cfs_time_current_64())) {
291                         /* If we have never tried this connection since the
292                            the last successful attempt, go with this one */
293                         if (cfs_time_beforeq_64(conn->oic_last_attempt,
294                                                imp->imp_last_success_conn)) {
295                                 imp_conn = conn;
296                                 break;
297                         }
298
299                         /* Both of these connections have already been tried
300                            since the last successful connection; just choose the
301                            least recently used */
302                         if (!imp_conn)
303                                 imp_conn = conn;
304                         else if (cfs_time_before_64(conn->oic_last_attempt,
305                                                     imp_conn->oic_last_attempt))
306                                 imp_conn = conn;
307                 }
308         }
309
310         /* if not found, simply choose the current one */
311         if (!imp_conn) {
312                 LASSERT(imp->imp_conn_current);
313                 imp_conn = imp->imp_conn_current;
314         }
315         LASSERT(imp_conn->oic_conn);
316
317         imp_conn->oic_last_attempt = cfs_time_current_64();
318
319         /* switch connection, don't mind if it's same as the current one */
320         if (imp->imp_connection)
321                 ptlrpc_put_connection(imp->imp_connection);
322         imp->imp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
323
324         dlmexp =  class_conn2export(&imp->imp_dlm_handle);
325         LASSERT(dlmexp != NULL);
326         if (dlmexp->exp_connection)
327                 ptlrpc_put_connection(dlmexp->exp_connection);
328         dlmexp->exp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
329         class_export_put(dlmexp);
330
331         if (imp->imp_conn_current != imp_conn) {
332                 if (imp->imp_conn_current)
333                         LCONSOLE_INFO("Changing connection for %s to %s/%s\n",
334                                       imp->imp_obd->obd_name,
335                                       imp_conn->oic_uuid.uuid,
336                                       libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
337                 imp->imp_conn_current = imp_conn;
338         }
339
340         CDEBUG(D_HA, "%s: import %p using connection %s/%s\n",
341                imp->imp_obd->obd_name, imp, imp_conn->oic_uuid.uuid,
342                libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
343
344         spin_unlock(&imp->imp_lock);
345
346         RETURN(0);
347 }
348
349 /*
350  * must be called under imp_lock
351  */
352 int ptlrpc_first_transno(struct obd_import *imp, __u64 *transno)
353 {
354         struct ptlrpc_request *req;
355         struct list_head *tmp;
356         
357         if (list_empty(&imp->imp_replay_list))
358                 return 0;
359         tmp = imp->imp_replay_list.next;
360         req = list_entry(tmp, struct ptlrpc_request, rq_replay_list);
361         *transno = req->rq_transno;
362         return 1;
363 }
364
365 int ptlrpc_connect_import(struct obd_import *imp, char *new_uuid)
366 {
367         struct obd_device *obd = imp->imp_obd;
368         int initial_connect = 0;
369         int set_transno = 0;
370         int rc;
371         __u64 committed_before_reconnect = 0;
372         struct ptlrpc_request *request;
373         int size[] = { sizeof(struct ptlrpc_body),
374                        sizeof(imp->imp_obd->u.cli.cl_target_uuid),
375                        sizeof(obd->obd_uuid),
376                        sizeof(imp->imp_dlm_handle),
377                        sizeof(imp->imp_connect_data) };
378         char *tmp[] = { NULL,
379                         obd2cli_tgt(imp->imp_obd),
380                         obd->obd_uuid.uuid,
381                         (char *)&imp->imp_dlm_handle,
382                         (char *)&imp->imp_connect_data };
383         struct ptlrpc_connect_async_args *aa;
384         ENTRY;
385
386         spin_lock(&imp->imp_lock);
387         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
388                 spin_unlock(&imp->imp_lock);
389                 CERROR("can't connect to a closed import\n");
390                 RETURN(-EINVAL);
391         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
392                 spin_unlock(&imp->imp_lock);
393                 CERROR("already connected\n");
394                 RETURN(0);
395         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING) {
396                 spin_unlock(&imp->imp_lock);
397                 CERROR("already connecting\n");
398                 RETURN(-EALREADY);
399         }
400
401         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CONNECTING);
402
403         imp->imp_conn_cnt++;
404         imp->imp_resend_replay = 0;
405
406         if (!lustre_handle_is_used(&imp->imp_remote_handle))
407                 initial_connect = 1;
408         else
409                 committed_before_reconnect = imp->imp_peer_committed_transno;
410
411         set_transno = ptlrpc_first_transno(imp, &imp->imp_connect_data.ocd_transno);
412         spin_unlock(&imp->imp_lock);
413
414         if (new_uuid) {
415                 struct obd_uuid uuid;
416
417                 obd_str2uuid(&uuid, new_uuid);
418                 rc = import_set_conn_priority(imp, &uuid);
419                 if (rc)
420                         GOTO(out, rc);
421         }
422
423         rc = import_select_connection(imp);
424         if (rc)
425                 GOTO(out, rc);
426
427         /* last in connection list */
428         if (imp->imp_conn_current->oic_item.next == &imp->imp_conn_list) {
429                 if (imp->imp_initial_recov_bk && initial_connect) {
430                         CDEBUG(D_HA, "Last connection attempt (%d) for %s\n",
431                                imp->imp_conn_cnt, obd2cli_tgt(imp->imp_obd));
432                         /* Don't retry if connect fails */
433                         rc = 0;
434                         obd_set_info_async(obd->obd_self_export,
435                                            strlen(KEY_INIT_RECOV),
436                                            KEY_INIT_RECOV,
437                                            sizeof(rc), &rc, NULL);
438                 }
439                 if (imp->imp_recon_bk) {
440                         CDEBUG(D_HA, "Last reconnection attempt (%d) for %s\n",
441                                imp->imp_conn_cnt, obd2cli_tgt(imp->imp_obd));
442                         spin_lock(&imp->imp_lock);
443                         imp->imp_last_recon = 1;
444                         spin_unlock(&imp->imp_lock);
445                 }
446         }
447
448         rc = sptlrpc_import_sec_adapt(imp, NULL, 0);
449         if (rc)
450                 GOTO(out, rc);
451
452         /* Reset connect flags to the originally requested flags, in case
453          * the server is updated on-the-fly we will get the new features. */
454         imp->imp_connect_data.ocd_connect_flags = imp->imp_connect_flags_orig;
455         rc = obd_reconnect(NULL, imp->imp_obd->obd_self_export, obd,
456                            &obd->obd_uuid, &imp->imp_connect_data);
457         if (rc)
458                 GOTO(out, rc);
459
460         request = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, imp->imp_connect_op,
461                                   5, size, tmp);
462         if (!request)
463                 GOTO(out, rc = -ENOMEM);
464
465 #ifndef __KERNEL__
466         lustre_msg_add_op_flags(request->rq_reqmsg, MSG_CONNECT_LIBCLIENT);
467 #endif
468         lustre_msg_add_op_flags(request->rq_reqmsg, MSG_CONNECT_NEXT_VER);
469
470         request->rq_send_state = LUSTRE_IMP_CONNECTING;
471         /* Allow a slightly larger reply for future growth compatibility */
472         size[REPLY_REC_OFF] = sizeof(struct obd_connect_data) +
473                               16 * sizeof(__u64);
474         ptlrpc_req_set_repsize(request, 2, size);
475         request->rq_interpret_reply = ptlrpc_connect_interpret;
476
477         CLASSERT(sizeof (*aa) <= sizeof (request->rq_async_args));
478         aa = (struct ptlrpc_connect_async_args *)&request->rq_async_args;
479         memset(aa, 0, sizeof *aa);
480
481         aa->pcaa_peer_committed = committed_before_reconnect;
482         aa->pcaa_initial_connect = initial_connect;
483
484         if (aa->pcaa_initial_connect) {
485                 spin_lock(&imp->imp_lock);
486                 imp->imp_replayable = 1;
487                 spin_unlock(&imp->imp_lock);
488                 /* On an initial connect, we don't know which one of a
489                    failover server pair is up.  Don't wait long. */
490 #ifdef CRAY_XT3
491                 request->rq_timeout = max((int)(obd_timeout / 2), 5);
492 #else
493                 request->rq_timeout = max((int)(obd_timeout / 20), 5);
494 #endif
495                 lustre_msg_add_op_flags(request->rq_reqmsg, 
496                                         MSG_CONNECT_INITIAL);
497         }
498
499         if (set_transno)
500                 lustre_msg_add_op_flags(request->rq_reqmsg, 
501                                         MSG_CONNECT_TRANSNO);
502
503         DEBUG_REQ(D_RPCTRACE, request, "(re)connect request");
504         ptlrpcd_add_req(request);
505         rc = 0;
506 out:
507         if (rc != 0) {
508                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
509         }
510
511         RETURN(rc);
512 }
513 EXPORT_SYMBOL(ptlrpc_connect_import);
514
515 static void ptlrpc_maybe_ping_import_soon(struct obd_import *imp)
516 {
517 #ifdef __KERNEL__
518         struct obd_import_conn *imp_conn;
519 #endif
520         int wake_pinger = 0;
521
522         ENTRY;
523
524         spin_lock(&imp->imp_lock);
525         if (list_empty(&imp->imp_conn_list))
526                 GOTO(unlock, 0);
527
528 #ifdef __KERNEL__
529         imp_conn = list_entry(imp->imp_conn_list.prev,
530                               struct obd_import_conn,
531                               oic_item);
532
533         if (imp->imp_conn_current != imp_conn) {
534                 ptlrpc_ping_import_soon(imp);
535                 wake_pinger = 1;
536         }
537 #else
538         /* liblustre has no pinger thead, so we wakup pinger anyway */
539         wake_pinger = 1;
540 #endif 
541
542  unlock:
543         spin_unlock(&imp->imp_lock);
544
545         if (wake_pinger)
546                 ptlrpc_pinger_wake_up();
547
548         EXIT;
549 }
550
551 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
552                                     void * data, int rc)
553 {
554         struct ptlrpc_connect_async_args *aa = data;
555         struct obd_import *imp = request->rq_import;
556         struct client_obd *cli = &imp->imp_obd->u.cli;
557         struct lustre_handle old_hdl;
558         int msg_flags;
559         ENTRY;
560
561         spin_lock(&imp->imp_lock);
562         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
563                 spin_unlock(&imp->imp_lock);
564                 RETURN(0);
565         }
566         spin_unlock(&imp->imp_lock);
567
568         if (rc)
569                 GOTO(out, rc);
570
571         LASSERT(imp->imp_conn_current);
572
573         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
574
575         /* All imports are pingable */
576         spin_lock(&imp->imp_lock);
577         imp->imp_pingable = 1;
578
579         if (aa->pcaa_initial_connect) {
580                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
581                         imp->imp_replayable = 1;
582                         spin_unlock(&imp->imp_lock);
583                         CDEBUG(D_HA, "connected to replayable target: %s\n",
584                                obd2cli_tgt(imp->imp_obd));
585                 } else {
586                         imp->imp_replayable = 0;
587                         spin_unlock(&imp->imp_lock);
588                 }
589
590                 if (msg_flags & MSG_CONNECT_NEXT_VER) {
591                         imp->imp_msg_magic = LUSTRE_MSG_MAGIC_V2;
592                         CDEBUG(D_RPCTRACE, "connect to %s with lustre_msg_v2\n",
593                                obd2cli_tgt(imp->imp_obd));
594                 } else {
595                         CDEBUG(D_RPCTRACE, "connect to %s with lustre_msg_v1\n",
596                                obd2cli_tgt(imp->imp_obd));
597                 }
598
599                 imp->imp_remote_handle =
600                                 *lustre_msg_get_handle(request->rq_repmsg);
601
602                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
603                 ptlrpc_activate_import(imp);
604                 GOTO(finish, rc = 0);
605         } else {
606                 spin_unlock(&imp->imp_lock);
607         }
608
609         /* Determine what recovery state to move the import to. */
610         if (MSG_CONNECT_RECONNECT & msg_flags) {
611                 memset(&old_hdl, 0, sizeof(old_hdl));
612                 if (!memcmp(&old_hdl, lustre_msg_get_handle(request->rq_repmsg),
613                             sizeof (old_hdl))) {
614                         CERROR("%s@%s didn't like our handle "LPX64
615                                ", failed\n", obd2cli_tgt(imp->imp_obd),
616                                imp->imp_connection->c_remote_uuid.uuid,
617                                imp->imp_dlm_handle.cookie);
618                         GOTO(out, rc = -ENOTCONN);
619                 }
620
621                 if (memcmp(&imp->imp_remote_handle,
622                            lustre_msg_get_handle(request->rq_repmsg),
623                            sizeof(imp->imp_remote_handle))) {
624                         int level = D_ERROR;
625                         /* Old MGC can reconnect to a restarted MGS */
626                         if (strcmp(imp->imp_obd->obd_type->typ_name,
627                                    LUSTRE_MGC_NAME) == 0) {
628                                 level = D_CONFIG;
629                         }
630                         CDEBUG(level, 
631                                "%s@%s changed handle from "LPX64" to "LPX64
632                                "; copying, but this may foreshadow disaster\n",
633                                obd2cli_tgt(imp->imp_obd),
634                                imp->imp_connection->c_remote_uuid.uuid,
635                                imp->imp_remote_handle.cookie,
636                                lustre_msg_get_handle(request->rq_repmsg)->
637                                         cookie);
638                         imp->imp_remote_handle =
639                                      *lustre_msg_get_handle(request->rq_repmsg);
640                 } else {
641                         CDEBUG(D_HA, "reconnected to %s@%s after partition\n",
642                                obd2cli_tgt(imp->imp_obd),
643                                imp->imp_connection->c_remote_uuid.uuid);
644                 }
645
646                 if (imp->imp_invalid) {
647                         IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
648                 } else if (MSG_CONNECT_RECOVERING & msg_flags) {
649                         CDEBUG(D_HA, "%s: reconnected to %s during replay\n",
650                                imp->imp_obd->obd_name,
651                                obd2cli_tgt(imp->imp_obd));
652
653                         spin_lock(&imp->imp_lock);
654                         imp->imp_resend_replay = 1;
655                         spin_unlock(&imp->imp_lock);
656
657                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
658                 } else {
659                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
660                 }
661         } else if ((MSG_CONNECT_RECOVERING & msg_flags) && !imp->imp_invalid) {
662                 LASSERT(imp->imp_replayable);
663                 imp->imp_remote_handle =
664                                 *lustre_msg_get_handle(request->rq_repmsg);
665                 imp->imp_last_replay_transno = 0;
666                 IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
667         } else {
668                 imp->imp_remote_handle =
669                                 *lustre_msg_get_handle(request->rq_repmsg);
670                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
671         }
672
673         /* Sanity checks for a reconnected import. */
674         if (!(imp->imp_replayable) != !(msg_flags & MSG_CONNECT_REPLAYABLE)) {
675                 CERROR("imp_replayable flag does not match server "
676                        "after reconnect. We should LBUG right here.\n");
677         }
678
679         if (lustre_msg_get_last_committed(request->rq_repmsg) <
680             aa->pcaa_peer_committed) {
681                 CERROR("%s went back in time (transno "LPD64
682                        " was previously committed, server now claims "LPD64
683                        ")!  See https://bugzilla.clusterfs.com/"
684                        "long_list.cgi?buglist=9646\n",
685                        obd2cli_tgt(imp->imp_obd), aa->pcaa_peer_committed,
686                        lustre_msg_get_last_committed(request->rq_repmsg));
687         }
688
689 finish:
690         rc = ptlrpc_import_recovery_state_machine(imp);
691         if (rc != 0) {
692                 if (rc == -ENOTCONN) {
693                         CDEBUG(D_HA, "evicted/aborted by %s@%s during recovery;"
694                                "invalidating and reconnecting\n",
695                                obd2cli_tgt(imp->imp_obd),
696                                imp->imp_connection->c_remote_uuid.uuid);
697                         ptlrpc_connect_import(imp, NULL);
698                         RETURN(0);
699                 }
700         } else {
701                 struct obd_connect_data *ocd;
702                 struct obd_export *exp;
703
704                 ocd = lustre_swab_repbuf(request, REPLY_REC_OFF, sizeof(*ocd),
705                                          lustre_swab_connect);
706
707                 spin_lock(&imp->imp_lock);
708                 list_del(&imp->imp_conn_current->oic_item);
709                 list_add(&imp->imp_conn_current->oic_item, &imp->imp_conn_list);
710                 imp->imp_last_success_conn =
711                         imp->imp_conn_current->oic_last_attempt;
712
713                 if (ocd == NULL) {
714                         spin_unlock(&imp->imp_lock);
715                         CERROR("Wrong connect data from server\n");
716                         rc = -EPROTO;
717                         GOTO(out, rc);
718                 }
719
720                 imp->imp_connect_data = *ocd;
721
722                 exp = class_conn2export(&imp->imp_dlm_handle);
723                 spin_unlock(&imp->imp_lock);
724
725                 /* check that server granted subset of flags we asked for. */
726                 LASSERTF((ocd->ocd_connect_flags &
727                           imp->imp_connect_flags_orig) ==
728                          ocd->ocd_connect_flags, LPX64" != "LPX64,
729                          imp->imp_connect_flags_orig, ocd->ocd_connect_flags);
730
731                 if (!exp) {
732                         /* This could happen if export is cleaned during the 
733                            connect attempt */
734                         CERROR("Missing export for %s\n", 
735                                imp->imp_obd->obd_name);
736                         GOTO(out, rc = -ENODEV);
737                 }
738                 exp->exp_connect_flags = ocd->ocd_connect_flags;
739                 imp->imp_obd->obd_self_export->exp_connect_flags = 
740                                                         ocd->ocd_connect_flags;
741                 class_export_put(exp);
742
743                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_OCD);
744
745                 if (!ocd->ocd_ibits_known &&
746                     ocd->ocd_connect_flags & OBD_CONNECT_IBITS)
747                         CERROR("Inodebits aware server returned zero compatible"
748                                " bits?\n");
749
750                 if ((ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
751                     (ocd->ocd_version > LUSTRE_VERSION_CODE +
752                                         LUSTRE_VERSION_OFFSET_WARN ||
753                      ocd->ocd_version < LUSTRE_VERSION_CODE -
754                                         LUSTRE_VERSION_OFFSET_WARN)) {
755                         /* Sigh, some compilers do not like #ifdef in the middle
756                            of macro arguments */
757 #ifdef __KERNEL__
758                         const char *older =
759                                 "older. Consider upgrading this client";
760 #else
761                         const char *older =
762                                 "older. Consider recompiling this application";
763 #endif
764                         const char *newer = "newer than client version";
765
766                         LCONSOLE_WARN("Server %s version (%d.%d.%d.%d) "
767                                       "is much %s (%s)\n",
768                                       obd2cli_tgt(imp->imp_obd),
769                                       OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
770                                       OBD_OCD_VERSION_MINOR(ocd->ocd_version),
771                                       OBD_OCD_VERSION_PATCH(ocd->ocd_version),
772                                       OBD_OCD_VERSION_FIX(ocd->ocd_version),
773                                       ocd->ocd_version > LUSTRE_VERSION_CODE ?
774                                       newer : older, LUSTRE_VERSION_STRING);
775                 }
776
777                 if (ocd->ocd_connect_flags & OBD_CONNECT_BRW_SIZE) {
778                         cli->cl_max_pages_per_rpc = 
779                                 ocd->ocd_brw_size >> CFS_PAGE_SHIFT;
780                 }
781
782                 imp->imp_obd->obd_namespace->ns_connect_flags = 
783                                                         ocd->ocd_connect_flags;
784                 imp->imp_obd->obd_namespace->ns_orig_connect_flags = 
785                                                         ocd->ocd_connect_flags;
786
787                 LASSERT((cli->cl_max_pages_per_rpc <= PTLRPC_MAX_BRW_PAGES) &&
788                         (cli->cl_max_pages_per_rpc > 0));
789         }
790
791 out:
792         if (rc != 0) {
793                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
794                 if (aa->pcaa_initial_connect && !imp->imp_initial_recov &&
795                     (request->rq_import_generation == imp->imp_generation))
796                         ptlrpc_deactivate_import(imp);
797
798                 if ((imp->imp_recon_bk && imp->imp_last_recon) ||
799                     (rc == -EACCES)) {
800                         /*
801                          * Give up trying to reconnect
802                          * EACCES means client has no permission for connection
803                          */
804                         imp->imp_obd->obd_no_recov = 1;
805                         ptlrpc_deactivate_import(imp);
806                 }
807
808                 if (rc == -EPROTO) {
809                         struct obd_connect_data *ocd;
810
811                         /* reply message might not be ready */
812                         if (request->rq_repmsg == NULL)
813                                 RETURN(-EPROTO);
814
815                         ocd = lustre_swab_repbuf(request, REPLY_REC_OFF,
816                                                  sizeof *ocd,
817                                                  lustre_swab_connect);
818                         if (ocd &&
819                             (ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
820                             (ocd->ocd_version != LUSTRE_VERSION_CODE)) {
821                            /* Actually servers are only supposed to refuse
822                               connection from liblustre clients, so we should
823                               never see this from VFS context */
824                                 LCONSOLE_ERROR_MSG(0x16a, "Server %s version "
825                                         "(%d.%d.%d.%d)"
826                                         " refused connection from this client "
827                                         "with an incompatible version (%s).  "
828                                         "Client must be recompiled\n",
829                                         obd2cli_tgt(imp->imp_obd),
830                                         OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
831                                         OBD_OCD_VERSION_MINOR(ocd->ocd_version),
832                                         OBD_OCD_VERSION_PATCH(ocd->ocd_version),
833                                         OBD_OCD_VERSION_FIX(ocd->ocd_version),
834                                         LUSTRE_VERSION_STRING);
835                                 ptlrpc_deactivate_import(imp);
836                                 IMPORT_SET_STATE(imp, LUSTRE_IMP_CLOSED);
837                         }
838                         RETURN(-EPROTO);
839                 }
840
841                 ptlrpc_maybe_ping_import_soon(imp);
842
843                 CDEBUG(D_HA, "recovery of %s on %s failed (%d)\n",
844                        obd2cli_tgt(imp->imp_obd),
845                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
846         }
847         
848         spin_lock(&imp->imp_lock);
849         imp->imp_last_recon = 0;
850         spin_unlock(&imp->imp_lock);
851
852         cfs_waitq_signal(&imp->imp_recovery_waitq);
853         RETURN(rc);
854 }
855
856 static int completed_replay_interpret(struct ptlrpc_request *req,
857                                     void * data, int rc)
858 {
859         ENTRY;
860         atomic_dec(&req->rq_import->imp_replay_inflight);
861         if (req->rq_status == 0) {
862                 ptlrpc_import_recovery_state_machine(req->rq_import);
863         } else {
864                 CDEBUG(D_HA, "%s: LAST_REPLAY message error: %d, "
865                        "reconnecting\n",
866                        req->rq_import->imp_obd->obd_name, req->rq_status);
867                 ptlrpc_connect_import(req->rq_import, NULL);
868         }
869
870         RETURN(0);
871 }
872
873 static int signal_completed_replay(struct obd_import *imp)
874 {
875         struct ptlrpc_request *req;
876         ENTRY;
877
878         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
879         atomic_inc(&imp->imp_replay_inflight);
880
881         req = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, OBD_PING, 1, NULL, NULL);
882         if (!req) {
883                 atomic_dec(&imp->imp_replay_inflight);
884                 RETURN(-ENOMEM);
885         }
886
887         ptlrpc_req_set_repsize(req, 1, NULL);
888         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
889         lustre_msg_add_flags(req->rq_reqmsg, 
890                              MSG_LOCK_REPLAY_DONE | MSG_REQ_REPLAY_DONE);
891         req->rq_timeout *= 3;
892         req->rq_interpret_reply = completed_replay_interpret;
893
894         ptlrpcd_add_req(req);
895         RETURN(0);
896 }
897
898 #ifdef __KERNEL__
899 static int ptlrpc_invalidate_import_thread(void *data)
900 {
901         struct obd_import *imp = data;
902
903         ENTRY;
904
905         ptlrpc_daemonize("ll_imp_inval");
906         
907         CDEBUG(D_HA, "thread invalidate import %s to %s@%s\n",
908                imp->imp_obd->obd_name, obd2cli_tgt(imp->imp_obd),
909                imp->imp_connection->c_remote_uuid.uuid);
910
911         ptlrpc_invalidate_import(imp);
912
913         if (obd_dump_on_eviction) {
914                 CERROR("dump the log upon eviction\n");
915                 libcfs_debug_dumplog();
916         }
917
918         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
919         ptlrpc_import_recovery_state_machine(imp);
920
921         RETURN(0);
922 }
923 #endif
924
925 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
926 {
927         int rc = 0;
928         int inflight;
929         char *target_start;
930         int target_len;
931
932         ENTRY;
933         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
934                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
935                           &target_start, &target_len);
936                 /* Don't care about MGC eviction */
937                 if (strcmp(imp->imp_obd->obd_type->typ_name,
938                            LUSTRE_MGC_NAME) != 0) {
939                         LCONSOLE_ERROR_MSG(0x167, "This client was evicted by "
940                                            "%.*s; in progress operations using "
941                                            "this service will fail.\n",
942                                            target_len, target_start);
943                 }
944                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
945                        obd2cli_tgt(imp->imp_obd),
946                        imp->imp_connection->c_remote_uuid.uuid);
947
948 #ifdef __KERNEL__
949                 rc = cfs_kernel_thread(ptlrpc_invalidate_import_thread, imp,
950                                        CLONE_VM | CLONE_FILES);
951                 if (rc < 0)
952                         CERROR("error starting invalidate thread: %d\n", rc);
953                 else
954                         rc = 0;
955                 RETURN(rc);
956 #else
957                 ptlrpc_invalidate_import(imp);
958
959                 IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
960 #endif
961         }
962
963         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
964                 CDEBUG(D_HA, "replay requested by %s\n",
965                        obd2cli_tgt(imp->imp_obd));
966                 rc = ptlrpc_replay_next(imp, &inflight);
967                 if (inflight == 0 &&
968                     atomic_read(&imp->imp_replay_inflight) == 0) {
969                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
970                         rc = ldlm_replay_locks(imp);
971                         if (rc)
972                                 GOTO(out, rc);
973                 }
974                 rc = 0;
975         }
976
977         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS) {
978                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
979                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_WAIT);
980                         rc = signal_completed_replay(imp);
981                         if (rc)
982                                 GOTO(out, rc);
983                 }
984
985         }
986
987         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT) {
988                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
989                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
990                 }
991         }
992
993         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
994                 CDEBUG(D_HA, "reconnected to %s@%s\n",
995                        obd2cli_tgt(imp->imp_obd),
996                        imp->imp_connection->c_remote_uuid.uuid);
997
998                 rc = ptlrpc_resend(imp);
999                 if (rc)
1000                         GOTO(out, rc);
1001                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
1002                 ptlrpc_activate_import(imp);
1003
1004                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
1005                           &target_start, &target_len);
1006                 LCONSOLE_INFO("%s: Connection restored to service %.*s "
1007                               "using nid %s.\n", imp->imp_obd->obd_name,
1008                               target_len, target_start,
1009                               libcfs_nid2str(imp->imp_connection->c_peer.nid));
1010         }
1011
1012         if (imp->imp_state == LUSTRE_IMP_FULL) {
1013                 cfs_waitq_signal(&imp->imp_recovery_waitq);
1014                 ptlrpc_wake_delayed(imp);
1015         }
1016
1017 out:
1018         RETURN(rc);
1019 }
1020
1021 static int back_to_sleep(void *unused)
1022 {
1023         return 0;
1024 }
1025
1026 int ptlrpc_disconnect_import(struct obd_import *imp, int noclose)
1027 {
1028         struct ptlrpc_request *req;
1029         int rq_opc, rc = 0;
1030         int nowait = imp->imp_obd->obd_force;
1031         ENTRY;
1032
1033         if (nowait)
1034                 GOTO(set_state, rc);
1035
1036         switch (imp->imp_connect_op) {
1037         case OST_CONNECT: rq_opc = OST_DISCONNECT; break;
1038         case MDS_CONNECT: rq_opc = MDS_DISCONNECT; break;
1039         case MGS_CONNECT: rq_opc = MGS_DISCONNECT; break;
1040         default:
1041                 CERROR("don't know how to disconnect from %s (connect_op %d)\n",
1042                        obd2cli_tgt(imp->imp_obd), imp->imp_connect_op);
1043                 RETURN(-EINVAL);
1044         }
1045
1046         if (ptlrpc_import_in_recovery(imp)) {
1047                 struct l_wait_info lwi;
1048                 cfs_duration_t timeout;
1049                 if (imp->imp_server_timeout)
1050                         timeout = cfs_time_seconds(obd_timeout / 2);
1051                 else
1052                         timeout = cfs_time_seconds(obd_timeout);
1053                 
1054                 timeout = MAX(timeout * HZ, 1);
1055                 
1056                 lwi = LWI_TIMEOUT_INTR(cfs_timeout_cap(timeout), 
1057                                        back_to_sleep, LWI_ON_SIGNAL_NOOP, NULL);
1058                 rc = l_wait_event(imp->imp_recovery_waitq,
1059                                   !ptlrpc_import_in_recovery(imp), &lwi);
1060
1061         }
1062
1063         spin_lock(&imp->imp_lock);
1064         if (imp->imp_state != LUSTRE_IMP_FULL)
1065                 GOTO(out, 0);
1066
1067         spin_unlock(&imp->imp_lock);
1068
1069         req = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, rq_opc, 1, NULL, NULL);
1070         if (req) {
1071                 /* We are disconnecting, do not retry a failed DISCONNECT rpc if
1072                  * it fails.  We can get through the above with a down server
1073                  * if the client doesn't know the server is gone yet. */
1074                 req->rq_no_resend = 1;
1075 #ifdef CRAY_XT3
1076                 req->rq_timeout = obd_timeout / 3;
1077 #else
1078                 req->rq_timeout = 5;
1079 #endif
1080                 IMPORT_SET_STATE(imp, LUSTRE_IMP_CONNECTING);
1081                 req->rq_send_state =  LUSTRE_IMP_CONNECTING;
1082                 ptlrpc_req_set_repsize(req, 1, NULL);
1083                 rc = ptlrpc_queue_wait(req);
1084                 ptlrpc_req_finished(req);
1085         }
1086
1087 set_state:
1088         spin_lock(&imp->imp_lock);
1089 out:
1090         if (noclose) 
1091                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
1092         else
1093                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CLOSED);
1094         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
1095         imp->imp_conn_cnt = 0;
1096         imp->imp_last_recon = 0;
1097         spin_unlock(&imp->imp_lock);
1098
1099         RETURN(rc);
1100 }
1101