lustre/ptlrpc/import.c

   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 Lustre, http://www.lustre.org.
   8  *
   9  *   Lustre is free software; you can redistribute it and/or
  10  *   modify it under the terms of version 2 of the GNU General Public
  11  *   License as published by the Free Software Foundation.
  12  *
  13  *   Lustre is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with Lustre; if not, write to the Free Software
  20  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_RPC
  24 #ifdef __KERNEL__
  25 # include <linux/config.h>
  26 # include <linux/module.h>
  27 # include <linux/kmod.h>
  28 #else
  29 # include <liblustre.h>
  30 #endif
  31
  32 #include <linux/obd_support.h>
  33 #include <linux/lustre_ha.h>
  34 #include <linux/lustre_net.h>
  35 #include <linux/lustre_import.h>
  36 #include <linux/lustre_export.h>
  37 #include <linux/obd.h>
  38 #include <linux/obd_class.h>
  39
  40 #include "ptlrpc_internal.h"
  41
  42 struct ptlrpc_connect_async_args {
  43          __u64 pcaa_peer_committed;
  44         int pcaa_initial_connect;
  45 };
  46
  47 /* A CLOSED import should remain so. */
  48 #define IMPORT_SET_STATE_NOLOCK(imp, state)                                    \
  49 do {                                                                           \
  50         if (imp->imp_state != LUSTRE_IMP_CLOSED) {                             \
  51                CDEBUG(D_HA, "%p %s: changing import state from %s to %s\n",    \
  52                       imp, imp->imp_target_uuid.uuid,                          \
  53                       ptlrpc_import_state_name(imp->imp_state),                \
  54                       ptlrpc_import_state_name(state));                        \
  55                imp->imp_state = state;                                         \
  56         }                                                                      \
  57 } while(0)
  58
  59 #define IMPORT_SET_STATE(imp, state)                    \
  60 do {                                                    \
  61         unsigned long flags;                            \
  62                                                         \
  63         spin_lock_irqsave(&imp->imp_lock, flags);       \
  64         IMPORT_SET_STATE_NOLOCK(imp, state);            \
  65         spin_unlock_irqrestore(&imp->imp_lock, flags);  \
  66 } while(0)
  67
  68
  69 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
  70                                     void * data, int rc);
  71 int ptlrpc_import_recovery_state_machine(struct obd_import *imp);
  72
  73 /* Only this function is allowed to change the import state when it is
  74  * CLOSED. I would rather refcount the import and free it after
  75  * disconnection like we do with exports. To do that, the client_obd
  76  * will need to save the peer info somewhere other than in the import,
  77  * though. */
  78 int ptlrpc_init_import(struct obd_import *imp)
  79 {
  80         unsigned long flags;
  81
  82         spin_lock_irqsave(&imp->imp_lock, flags);
  83
  84         imp->imp_generation++;
  85         imp->imp_state =  LUSTRE_IMP_NEW;
  86
  87         spin_unlock_irqrestore(&imp->imp_lock, flags);
  88
  89         return 0;
  90 }
  91
  92 /* Returns true if import was FULL, false if import was already not
  93  * connected.
  94  */
  95 int ptlrpc_set_import_discon(struct obd_import *imp)
  96 {
  97         unsigned long flags;
  98         int rc = 0;
  99
 100         spin_lock_irqsave(&imp->imp_lock, flags);
 101
 102         if (imp->imp_state == LUSTRE_IMP_FULL) {
 103                 CERROR("%s: connection lost to %s@%s\n",
 104                        imp->imp_obd->obd_name,
 105                        imp->imp_target_uuid.uuid,
 106                        imp->imp_connection->c_remote_uuid.uuid);
 107                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
 108                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 109                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_DISCON);
 110                 rc = 1;
 111         } else {
 112                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 113                 CDEBUG(D_HA, "%p %s: import already not connected: %s\n",
 114                        imp,imp->imp_client->cli_name,
 115                        ptlrpc_import_state_name(imp->imp_state));
 116         }
 117
 118         return rc;
 119 }
 120
 121 /*
 122  * This acts as a barrier; all existing requests are rejected, and
 123  * no new requests will be accepted until the import is valid again.
 124  */
 125 void ptlrpc_deactivate_import(struct obd_import *imp)
 126 {
 127         unsigned long flags;
 128         ENTRY;
 129
 130         spin_lock_irqsave(&imp->imp_lock, flags);
 131         CDEBUG(D_HA, "setting import %s INVALID\n",
 132                imp->imp_target_uuid.uuid);
 133         imp->imp_invalid = 1;
 134         imp->imp_generation++;
 135         spin_unlock_irqrestore(&imp->imp_lock, flags);
 136
 137         ptlrpc_abort_inflight(imp);
 138         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
 139 }
 140
 141 /*
 142  * This function will invalidate the import, if necessary, then block
 143  * for all the RPC completions, and finally notify the obd to
 144  * invalidate its state (ie cancel locks, clear pending requests,
 145  * etc).
 146  *
 147  * in_rpc: true if this is called while processing an rpc, like
 148  *    CONNECT. It will allow for one RPC to be inflight while
 149  *    waiting for requests to complete. Ugly, yes, but I don't see an
 150  *    cleaner way right now.
 151  */
 152 void ptlrpc_invalidate_import(struct obd_import *imp, int in_rpc)
 153 {
 154         struct l_wait_info lwi;
 155         unsigned long timeout;
 156         int inflight = 0;
 157         int rc;
 158
 159         if (!imp->imp_invalid)
 160                 ptlrpc_deactivate_import(imp);
 161
 162         LASSERT(imp->imp_invalid);
 163
 164         if (in_rpc)
 165                 inflight = 1;
 166
 167         /* wait for all requests to error out and call completion
 168            callbacks */
 169         if (imp->imp_server_timeout)
 170                 timeout = obd_timeout / 2;
 171         else
 172                 timeout = obd_timeout;
 173         timeout = MAX(timeout * HZ, 1);
 174         lwi = LWI_TIMEOUT_INTR(timeout, NULL, NULL, NULL);
 175         rc = l_wait_event(imp->imp_recovery_waitq,
 176                           (atomic_read(&imp->imp_inflight) == inflight),
 177                           &lwi);
 178
 179         if (rc)
 180                 CERROR("%s: rc = %d waiting for callback (%d != %d)\n",
 181                        imp->imp_target_uuid.uuid, rc,
 182                        atomic_read(&imp->imp_inflight), inflight);
 183
 184         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
 185 }
 186
 187 void ptlrpc_activate_import(struct obd_import *imp)
 188 {
 189         struct obd_device *obd = imp->imp_obd;
 190         unsigned long flags;
 191
 192         spin_lock_irqsave(&imp->imp_lock, flags);
 193         imp->imp_invalid = 0;
 194         spin_unlock_irqrestore(&imp->imp_lock, flags);
 195
 196         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
 197 }
 198
 199 void ptlrpc_fail_import(struct obd_import *imp, int generation)
 200 {
 201         ENTRY;
 202
 203         LASSERT (!imp->imp_dlm_fake);
 204
 205         if (ptlrpc_set_import_discon(imp)) {
 206                 unsigned long flags;
 207
 208                 if (!imp->imp_replayable) {
 209                         CDEBUG(D_HA, "import %s@%s for %s not replayable, "
 210                                "auto-deactivating\n",
 211                                imp->imp_target_uuid.uuid,
 212                                imp->imp_connection->c_remote_uuid.uuid,
 213                                imp->imp_obd->obd_name);
 214                         ptlrpc_deactivate_import(imp);
 215                 }
 216
 217                 CDEBUG(D_HA, "%s: waking up pinger\n",
 218                        imp->imp_target_uuid.uuid);
 219
 220                 spin_lock_irqsave(&imp->imp_lock, flags);
 221                 imp->imp_force_verify = 1;
 222                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 223
 224                 ptlrpc_pinger_wake_up();
 225         }
 226         EXIT;
 227 }
 228
 229 #define ATTEMPT_TOO_SOON(last)  \
 230         ((last) && ((long)(jiffies - (last)) <= (long)(obd_timeout * 2 * HZ)))
 231
 232 static int import_select_connection(struct obd_import *imp)
 233 {
 234         struct obd_import_conn *imp_conn, *tmp;
 235         struct obd_export *dlmexp;
 236         int found = 0;
 237         ENTRY;
 238
 239         spin_lock(&imp->imp_lock);
 240
 241         if (list_empty(&imp->imp_conn_list)) {
 242                 CERROR("no available connections on imp %p@%s\n",
 243                         imp, imp->imp_obd->obd_name);
 244                 spin_unlock(&imp->imp_lock);
 245                 RETURN(-EINVAL);
 246         }
 247
 248         list_for_each_entry(imp_conn, &imp->imp_conn_list, oic_item) {
 249                 if (!ATTEMPT_TOO_SOON(imp_conn->oic_last_attempt)) {
 250                         found = 1;
 251                         break;
 252                 }
 253         }
 254
 255         /* if not found, simply choose the current one */
 256         if (!found) {
 257                 CWARN("obd %s imp 0x%p: all connections have been "
 258                       "tried recently\n", imp->imp_obd->obd_name, imp);
 259                 LASSERT(imp->imp_conn_current);
 260                 imp_conn = imp->imp_conn_current;
 261         }
 262         LASSERT(imp_conn->oic_conn);
 263
 264         imp_conn->oic_last_attempt = jiffies;
 265
 266         /* move the items ahead of the selected one to list tail */
 267         while (1) {
 268                 tmp= list_entry(imp->imp_conn_list.next,
 269                                 struct obd_import_conn, oic_item);
 270                 if (tmp == imp_conn)
 271                         break;
 272                 list_del(&tmp->oic_item);
 273                 list_add_tail(&tmp->oic_item, &imp->imp_conn_list);
 274         }
 275
 276         /* switch connection, don't mind if it's same as the current one */
 277         if (imp->imp_connection)
 278                 ptlrpc_put_connection(imp->imp_connection);
 279         imp->imp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 280
 281         dlmexp =  class_conn2export(&imp->imp_dlm_handle);
 282         LASSERT(dlmexp != NULL);
 283         if (dlmexp->exp_connection)
 284                 ptlrpc_put_connection(imp->imp_connection);
 285         dlmexp->exp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 286         class_export_put(dlmexp);
 287
 288         imp->imp_conn_current = imp_conn;
 289         CWARN("obd %s imp 0x%p: select conn %s\n",
 290                imp->imp_obd->obd_name, imp,
 291                imp_conn->oic_uuid.uuid);
 292         spin_unlock(&imp->imp_lock);
 293
 294         RETURN(0);
 295 }
 296
 297
 298
 299 int ptlrpc_connect_import(struct obd_import *imp, char * new_uuid)
 300 {
 301         struct obd_device *obd = imp->imp_obd;
 302         int initial_connect = 0;
 303         int rc;
 304         __u64 committed_before_reconnect = 0;
 305         struct ptlrpc_request *request;
 306         int size[] = {sizeof(imp->imp_target_uuid),
 307                                  sizeof(obd->obd_uuid),
 308                                  sizeof(imp->imp_dlm_handle),
 309                                  sizeof(unsigned long)};
 310         char *tmp[] = {imp->imp_target_uuid.uuid,
 311                        obd->obd_uuid.uuid,
 312                        (char *)&imp->imp_dlm_handle,
 313                        (char *)&imp->imp_connect_flags}; /* XXX: make this portable! */
 314         struct ptlrpc_connect_async_args *aa;
 315         unsigned long flags;
 316
 317         spin_lock_irqsave(&imp->imp_lock, flags);
 318         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 319                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 320                 CERROR("can't connect to a closed import\n");
 321                 RETURN(-EINVAL);
 322         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
 323                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 324                 CERROR("already connected\n");
 325                 RETURN(0);
 326         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING) {
 327                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 328                 CERROR("already connecting\n");
 329                 RETURN(-EALREADY);
 330         }
 331
 332         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CONNECTING);
 333
 334         imp->imp_resend_replay = 0;
 335
 336         if (imp->imp_remote_handle.cookie == 0) {
 337                 initial_connect = 1;
 338         } else {
 339                 committed_before_reconnect = imp->imp_peer_committed_transno;;
 340                 imp->imp_conn_cnt++;
 341         }
 342
 343
 344         spin_unlock_irqrestore(&imp->imp_lock, flags);
 345
 346         if (new_uuid) {
 347                 struct obd_uuid uuid;
 348
 349                 obd_str2uuid(&uuid, new_uuid);
 350
 351                 rc = import_set_conn_priority(imp, &uuid);
 352                 if (rc)
 353                         GOTO(out, rc);
 354         }
 355         rc = import_select_connection(imp);
 356         if (rc)
 357                 GOTO(out, rc);
 358
 359         request = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION,
 360                                   imp->imp_connect_op, 4, size, tmp);
 361         if (!request)
 362                 GOTO(out, rc = -ENOMEM);
 363
 364 #ifndef __KERNEL__
 365         lustre_msg_add_op_flags(request->rq_reqmsg, MSG_CONNECT_LIBCLIENT);
 366 #endif
 367
 368         request->rq_send_state = LUSTRE_IMP_CONNECTING;
 369         request->rq_replen = lustre_msg_size(0, NULL);
 370         request->rq_interpret_reply = ptlrpc_connect_interpret;
 371
 372         LASSERT (sizeof (*aa) <= sizeof (request->rq_async_args));
 373         aa = (struct ptlrpc_connect_async_args *)&request->rq_async_args;
 374         memset(aa, 0, sizeof *aa);
 375
 376         aa->pcaa_peer_committed = committed_before_reconnect;
 377         aa->pcaa_initial_connect = initial_connect;
 378
 379         if (aa->pcaa_initial_connect) {
 380                 lustre_msg_add_op_flags(request->rq_reqmsg,
 381                                         MSG_CONNECT_INITIAL);
 382                 imp->imp_replayable = 1;
 383         }
 384
 385         ptlrpcd_add_req(request);
 386         rc = 0;
 387         imp->imp_connect_start = jiffies;
 388 out:
 389         if (rc != 0) {
 390                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 391         }
 392
 393         RETURN(rc);
 394 }
 395
 396 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
 397                                     void *data, int rc)
 398 {
 399         struct ptlrpc_connect_async_args *aa = data;
 400         struct obd_import *imp = request->rq_import;
 401         struct lustre_handle old_hdl;
 402         unsigned long flags;
 403         int msg_flags;
 404         ENTRY;
 405
 406         spin_lock_irqsave(&imp->imp_lock, flags);
 407         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 408                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 409                 RETURN(0);
 410         }
 411         spin_unlock_irqrestore(&imp->imp_lock, flags);
 412
 413         if (rc)
 414                 GOTO(out, rc);
 415         LASSERT(imp->imp_conn_current);
 416         imp->imp_conn_current->oic_last_attempt = 0;
 417
 418         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
 419
 420         if (aa->pcaa_initial_connect) {
 421                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
 422                         CDEBUG(D_HA, "connected to replayable target: %s\n",
 423                                imp->imp_target_uuid.uuid);
 424                         imp->imp_pingable = imp->imp_replayable = 1;
 425                 } else {
 426                         imp->imp_replayable = 0;
 427                 }
 428                 LASSERTF(imp->imp_conn_cnt < request->rq_repmsg->conn_cnt,
 429                          "imp conn_cnt %d req conn_cnt %d",
 430                          imp->imp_conn_cnt, request->rq_repmsg->conn_cnt);
 431                 imp->imp_conn_cnt = request->rq_repmsg->conn_cnt;
 432                 imp->imp_remote_handle = request->rq_repmsg->handle;
 433                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 434                 GOTO(finish, rc = 0);
 435         }
 436
 437         /* Determine what recovery state to move the import to. */
 438         if (MSG_CONNECT_RECONNECT & msg_flags) {
 439                 memset(&old_hdl, 0, sizeof(old_hdl));
 440                 if (!memcmp(&old_hdl, &request->rq_repmsg->handle,
 441                             sizeof (old_hdl))) {
 442                         CERROR("%s@%s didn't like our handle "LPX64
 443                                ", failed\n", imp->imp_target_uuid.uuid,
 444                                imp->imp_connection->c_remote_uuid.uuid,
 445                                imp->imp_dlm_handle.cookie);
 446                         GOTO(out, rc = -ENOTCONN);
 447                 }
 448
 449                 if (memcmp(&imp->imp_remote_handle, &request->rq_repmsg->handle,
 450                            sizeof(imp->imp_remote_handle))) {
 451                         CERROR("%s@%s changed handle from "LPX64" to "LPX64
 452                                "; copying, but this may foreshadow disaster\n",
 453                                imp->imp_target_uuid.uuid,
 454                                imp->imp_connection->c_remote_uuid.uuid,
 455                                imp->imp_remote_handle.cookie,
 456                                request->rq_repmsg->handle.cookie);
 457                         imp->imp_remote_handle = request->rq_repmsg->handle;
 458                 } else {
 459                         CDEBUG(D_HA, "reconnected to %s@%s after partition\n",
 460                                imp->imp_target_uuid.uuid,
 461                                imp->imp_connection->c_remote_uuid.uuid);
 462                 }
 463
 464                 if (imp->imp_invalid) {
 465                         IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 466                 } else if (MSG_CONNECT_RECOVERING & msg_flags) {
 467                         CDEBUG(D_HA, "%s: reconnected to %s during replay\n",
 468                                imp->imp_obd->obd_name,
 469                                imp->imp_target_uuid.uuid);
 470                         imp->imp_resend_replay = 1;
 471                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
 472                 } else {
 473                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 474                 }
 475         } else if ((MSG_CONNECT_RECOVERING & msg_flags) && !imp->imp_invalid) {
 476                 LASSERT(imp->imp_replayable);
 477                 imp->imp_remote_handle = request->rq_repmsg->handle;
 478                 imp->imp_last_replay_transno = 0;
 479                 IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
 480         } else {
 481                 CDEBUG(D_HA, "oops! we get evicted from %s\n", imp->imp_target_uuid.uuid);
 482                 imp->imp_remote_handle = request->rq_repmsg->handle;
 483                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 484         }
 485
 486         /* Sanity checks for a reconnected import. */
 487         if (!(imp->imp_replayable) != !(msg_flags & MSG_CONNECT_REPLAYABLE)) {
 488                 CERROR("imp_replayable flag does not match server "
 489                        "after reconnect. We should LBUG right here.\n");
 490         }
 491
 492         if (request->rq_repmsg->last_committed < aa->pcaa_peer_committed) {
 493                 CERROR("%s went back in time (transno "LPD64
 494                        " was previously committed, server now claims "LPD64
 495                        ")! is shared storage not coherent?\n",
 496                        imp->imp_target_uuid.uuid,
 497                        aa->pcaa_peer_committed,
 498                        request->rq_repmsg->last_committed);
 499         }
 500
 501 finish:
 502         rc = ptlrpc_import_recovery_state_machine(imp);
 503         if (rc != 0) {
 504                 if (rc == -ENOTCONN) {
 505                         CDEBUG(D_HA, "evicted/aborted by %s@%s during recovery;"
 506                                "invalidating and reconnecting\n",
 507                                imp->imp_target_uuid.uuid,
 508                                imp->imp_connection->c_remote_uuid.uuid);
 509                         ptlrpc_connect_import(imp, NULL);
 510                         RETURN(0);
 511                 }
 512         }
 513  out:
 514         if (rc != 0) {
 515                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 516                 if (aa->pcaa_initial_connect && !imp->imp_initial_recov)
 517                         ptlrpc_deactivate_import(imp);
 518                 CDEBUG(D_HA, "recovery of %s on %s failed (%d)\n",
 519                        imp->imp_target_uuid.uuid,
 520                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
 521         }
 522
 523         wake_up(&imp->imp_recovery_waitq);
 524         RETURN(rc);
 525 }
 526
 527 static int completed_replay_interpret(struct ptlrpc_request *req,
 528                                       void *data, int rc)
 529 {
 530         atomic_dec(&req->rq_import->imp_replay_inflight);
 531         if (req->rq_status == 0) {
 532                 ptlrpc_import_recovery_state_machine(req->rq_import);
 533         } else {
 534                 CDEBUG(D_HA, "%s: LAST_REPLAY message error: %d, "
 535                        "reconnecting\n",
 536                        req->rq_import->imp_obd->obd_name, req->rq_status);
 537                 ptlrpc_connect_import(req->rq_import, NULL);
 538         }
 539
 540         RETURN(0);
 541 }
 542
 543 static int signal_completed_replay(struct obd_import *imp)
 544  {
 545         struct ptlrpc_request *req;
 546         ENTRY;
 547
 548         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
 549         atomic_inc(&imp->imp_replay_inflight);
 550
 551         req = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, OBD_PING, 0, NULL, NULL);
 552         if (!req)
 553                 RETURN(-ENOMEM);
 554
 555         req->rq_replen = lustre_msg_size(0, NULL);
 556         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
 557         req->rq_reqmsg->flags |= MSG_LAST_REPLAY;
 558         req->rq_timeout *= 3;
 559         req->rq_interpret_reply = completed_replay_interpret;
 560
 561         ptlrpcd_add_req(req);
 562         RETURN(0);
 563 }
 564
 565 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
 566 {
 567         int rc = 0;
 568         int inflight;
 569
 570         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
 571                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
 572                        imp->imp_target_uuid.uuid,
 573                        imp->imp_connection->c_remote_uuid.uuid);
 574
 575                 ptlrpc_invalidate_import(imp, 1);
 576
 577                 IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 578         }
 579
 580         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
 581                 CDEBUG(D_HA, "replay requested by %s\n",
 582                        imp->imp_target_uuid.uuid);
 583                 rc = ptlrpc_replay_next(imp, &inflight);
 584                 if (inflight == 0 &&
 585                     atomic_read(&imp->imp_replay_inflight) == 0) {
 586                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
 587                         rc = ldlm_replay_locks(imp);
 588                         if (rc)
 589                                 GOTO(out, rc);
 590                 }
 591                 rc = 0;
 592         }
 593
 594         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS) {
 595                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 596                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_WAIT);
 597                         rc = signal_completed_replay(imp);
 598                         if (rc)
 599                                 GOTO(out, rc);
 600                 }
 601
 602         }
 603
 604         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT) {
 605                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 606                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 607                 }
 608         }
 609
 610         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
 611                 CDEBUG(D_HA, "reconnected to %s@%s\n",
 612                        imp->imp_target_uuid.uuid,
 613                        imp->imp_connection->c_remote_uuid.uuid);
 614
 615                 rc = ptlrpc_resend(imp);
 616                 if (rc)
 617                         GOTO(out, rc);
 618                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 619                 ptlrpc_activate_import(imp);
 620                 CERROR("%s: connection restored to %s@%s\n",
 621                        imp->imp_obd->obd_name,
 622                        imp->imp_target_uuid.uuid,
 623                        imp->imp_connection->c_remote_uuid.uuid);
 624         }
 625
 626         if (imp->imp_state == LUSTRE_IMP_FULL) {
 627                 wake_up(&imp->imp_recovery_waitq);
 628                 ptlrpc_wake_delayed(imp);
 629         }
 630
 631  out:
 632         RETURN(rc);
 633 }
 634
 635 static int back_to_sleep(void *unused)
 636 {
 637         return 0;
 638 }
 639
 640 int ptlrpc_disconnect_import(struct obd_import *imp)
 641 {
 642         struct ptlrpc_request *request;
 643         int rq_opc;
 644         int rc = 0;
 645         unsigned long flags;
 646         ENTRY;
 647
 648         switch (imp->imp_connect_op) {
 649         case OST_CONNECT: rq_opc = OST_DISCONNECT; break;
 650         case MDS_CONNECT: rq_opc = MDS_DISCONNECT; break;
 651         case MGMT_CONNECT: rq_opc = MGMT_DISCONNECT; break;
 652         default:
 653                 CERROR("don't know how to disconnect from %s (connect_op %d)\n",
 654                        imp->imp_target_uuid.uuid, imp->imp_connect_op);
 655                 RETURN(-EINVAL);
 656         }
 657
 658
 659         if (ptlrpc_import_in_recovery(imp)) {
 660                 struct l_wait_info lwi;
 661                 unsigned long timeout;
 662                 if (imp->imp_server_timeout)
 663                         timeout = obd_timeout / 2;
 664                 else
 665                         timeout = obd_timeout;
 666                 timeout = MAX(timeout * HZ, 1);
 667                 lwi = LWI_TIMEOUT_INTR(obd_timeout, back_to_sleep, NULL, NULL);
 668                 rc = l_wait_event(imp->imp_recovery_waitq,
 669                                   !ptlrpc_import_in_recovery(imp), &lwi);
 670
 671         }
 672
 673         spin_lock_irqsave(&imp->imp_lock, flags);
 674         if (imp->imp_state != LUSTRE_IMP_FULL) {
 675                 GOTO(out, 0);
 676         }
 677         spin_unlock_irqrestore(&imp->imp_lock, flags);
 678
 679         request = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, rq_opc,
 680                                   0, NULL, NULL);
 681         if (request) {
 682                 /* For non-replayable connections, don't attempt
 683                    reconnect if this fails */
 684                 if (!imp->imp_replayable) {
 685                         request->rq_no_resend = 1;
 686                         IMPORT_SET_STATE(imp, LUSTRE_IMP_CONNECTING);
 687                         request->rq_send_state =  LUSTRE_IMP_CONNECTING;
 688                 }
 689                 request->rq_replen = lustre_msg_size(0, NULL);
 690                 rc = ptlrpc_queue_wait(request);
 691                 ptlrpc_req_finished(request);
 692         }
 693
 694         spin_lock_irqsave(&imp->imp_lock, flags);
 695 out:
 696         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CLOSED);
 697         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
 698         imp->imp_conn_cnt = 0;
 699         spin_unlock_irqrestore(&imp->imp_lock, flags);
 700
 701         RETURN(rc);
 702 }
 703