drivers/staging/lustre/lustre/ptlrpc/import.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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2015, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lustre/ptlrpc/import.c
  33  *
  34  * Author: Mike Shaver <shaver@clusterfs.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_RPC
  38
  39 #include <obd_support.h>
  40 #include <lustre_ha.h>
  41 #include <lustre_net.h>
  42 #include <lustre_import.h>
  43 #include <lustre_export.h>
  44 #include <obd.h>
  45 #include <obd_cksum.h>
  46 #include <obd_class.h>
  47
  48 #include "ptlrpc_internal.h"
  49
  50 struct ptlrpc_connect_async_args {
  51          __u64 pcaa_peer_committed;
  52         int pcaa_initial_connect;
  53 };
  54
  55 /**
  56  * Updates import \a imp current state to provided \a state value
  57  * Helper function. Must be called under imp_lock.
  58  */
  59 static void __import_set_state(struct obd_import *imp,
  60                                enum lustre_imp_state state)
  61 {
  62         switch (state) {
  63         case LUSTRE_IMP_CLOSED:
  64         case LUSTRE_IMP_NEW:
  65         case LUSTRE_IMP_DISCON:
  66         case LUSTRE_IMP_CONNECTING:
  67                 break;
  68         case LUSTRE_IMP_REPLAY_WAIT:
  69                 imp->imp_replay_state = LUSTRE_IMP_REPLAY_LOCKS;
  70                 break;
  71         default:
  72                 imp->imp_replay_state = LUSTRE_IMP_REPLAY;
  73         }
  74
  75         imp->imp_state = state;
  76         imp->imp_state_hist[imp->imp_state_hist_idx].ish_state = state;
  77         imp->imp_state_hist[imp->imp_state_hist_idx].ish_time =
  78                 ktime_get_real_seconds();
  79         imp->imp_state_hist_idx = (imp->imp_state_hist_idx + 1) %
  80                 IMP_STATE_HIST_LEN;
  81 }
  82
  83 /* A CLOSED import should remain so. */
  84 #define IMPORT_SET_STATE_NOLOCK(imp, state)                                    \
  85 do {                                                                           \
  86         if (imp->imp_state != LUSTRE_IMP_CLOSED) {                             \
  87                 CDEBUG(D_HA, "%p %s: changing import state from %s to %s\n",   \
  88                        imp, obd2cli_tgt(imp->imp_obd),                         \
  89                        ptlrpc_import_state_name(imp->imp_state),               \
  90                        ptlrpc_import_state_name(state));                       \
  91                 __import_set_state(imp, state);                                \
  92         }                                                                      \
  93 } while (0)
  94
  95 #define IMPORT_SET_STATE(imp, state)                                    \
  96 do {                                                                    \
  97         spin_lock(&imp->imp_lock);                                      \
  98         IMPORT_SET_STATE_NOLOCK(imp, state);                            \
  99         spin_unlock(&imp->imp_lock);                                    \
 100 } while (0)
 101
 102 static int ptlrpc_connect_interpret(const struct lu_env *env,
 103                                     struct ptlrpc_request *request,
 104                                     void *data, int rc);
 105 int ptlrpc_import_recovery_state_machine(struct obd_import *imp);
 106
 107 /* Only this function is allowed to change the import state when it is
 108  * CLOSED. I would rather refcount the import and free it after
 109  * disconnection like we do with exports. To do that, the client_obd
 110  * will need to save the peer info somewhere other than in the import,
 111  * though.
 112  */
 113 int ptlrpc_init_import(struct obd_import *imp)
 114 {
 115         spin_lock(&imp->imp_lock);
 116
 117         imp->imp_generation++;
 118         imp->imp_state = LUSTRE_IMP_NEW;
 119
 120         spin_unlock(&imp->imp_lock);
 121
 122         return 0;
 123 }
 124 EXPORT_SYMBOL(ptlrpc_init_import);
 125
 126 #define UUID_STR "_UUID"
 127 static void deuuidify(char *uuid, const char *prefix, char **uuid_start,
 128                       int *uuid_len)
 129 {
 130         *uuid_start = !prefix || strncmp(uuid, prefix, strlen(prefix))
 131                 ? uuid : uuid + strlen(prefix);
 132
 133         *uuid_len = strlen(*uuid_start);
 134
 135         if (*uuid_len < strlen(UUID_STR))
 136                 return;
 137
 138         if (!strncmp(*uuid_start + *uuid_len - strlen(UUID_STR),
 139                      UUID_STR, strlen(UUID_STR)))
 140                 *uuid_len -= strlen(UUID_STR);
 141 }
 142
 143 /**
 144  * Returns true if import was FULL, false if import was already not
 145  * connected.
 146  * @imp - import to be disconnected
 147  * @conn_cnt - connection count (epoch) of the request that timed out
 148  *           and caused the disconnection.  In some cases, multiple
 149  *           inflight requests can fail to a single target (e.g. OST
 150  *           bulk requests) and if one has already caused a reconnection
 151  *           (increasing the import->conn_cnt) the older failure should
 152  *           not also cause a reconnection.  If zero it forces a reconnect.
 153  */
 154 int ptlrpc_set_import_discon(struct obd_import *imp, __u32 conn_cnt)
 155 {
 156         int rc = 0;
 157
 158         spin_lock(&imp->imp_lock);
 159
 160         if (imp->imp_state == LUSTRE_IMP_FULL &&
 161             (conn_cnt == 0 || conn_cnt == imp->imp_conn_cnt)) {
 162                 char *target_start;
 163                 int   target_len;
 164
 165                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
 166                           &target_start, &target_len);
 167
 168                 if (imp->imp_replayable) {
 169                         LCONSOLE_WARN("%s: Connection to %.*s (at %s) was lost; in progress operations using this service will wait for recovery to complete\n",
 170                                       imp->imp_obd->obd_name, target_len, target_start,
 171                                       libcfs_nid2str(imp->imp_connection->c_peer.nid));
 172                 } else {
 173                         LCONSOLE_ERROR_MSG(0x166, "%s: Connection to %.*s (at %s) was lost; in progress operations using this service will fail\n",
 174                                            imp->imp_obd->obd_name,
 175                                            target_len, target_start,
 176                                            libcfs_nid2str(imp->imp_connection->c_peer.nid));
 177                 }
 178                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
 179                 spin_unlock(&imp->imp_lock);
 180
 181                 if (obd_dump_on_timeout)
 182                         libcfs_debug_dumplog();
 183
 184                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_DISCON);
 185                 rc = 1;
 186         } else {
 187                 spin_unlock(&imp->imp_lock);
 188                 CDEBUG(D_HA, "%s: import %p already %s (conn %u, was %u): %s\n",
 189                        imp->imp_client->cli_name, imp,
 190                        (imp->imp_state == LUSTRE_IMP_FULL &&
 191                         imp->imp_conn_cnt > conn_cnt) ?
 192                        "reconnected" : "not connected", imp->imp_conn_cnt,
 193                        conn_cnt, ptlrpc_import_state_name(imp->imp_state));
 194         }
 195
 196         return rc;
 197 }
 198
 199 /*
 200  * This acts as a barrier; all existing requests are rejected, and
 201  * no new requests will be accepted until the import is valid again.
 202  */
 203 void ptlrpc_deactivate_import(struct obd_import *imp)
 204 {
 205         CDEBUG(D_HA, "setting import %s INVALID\n", obd2cli_tgt(imp->imp_obd));
 206
 207         spin_lock(&imp->imp_lock);
 208         imp->imp_invalid = 1;
 209         imp->imp_generation++;
 210         spin_unlock(&imp->imp_lock);
 211
 212         ptlrpc_abort_inflight(imp);
 213         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
 214 }
 215 EXPORT_SYMBOL(ptlrpc_deactivate_import);
 216
 217 static unsigned int
 218 ptlrpc_inflight_deadline(struct ptlrpc_request *req, time64_t now)
 219 {
 220         long dl;
 221
 222         if (!(((req->rq_phase == RQ_PHASE_RPC) && !req->rq_waiting) ||
 223               (req->rq_phase == RQ_PHASE_BULK) ||
 224               (req->rq_phase == RQ_PHASE_NEW)))
 225                 return 0;
 226
 227         if (req->rq_timedout)
 228                 return 0;
 229
 230         if (req->rq_phase == RQ_PHASE_NEW)
 231                 dl = req->rq_sent;
 232         else
 233                 dl = req->rq_deadline;
 234
 235         if (dl <= now)
 236                 return 0;
 237
 238         return dl - now;
 239 }
 240
 241 static unsigned int ptlrpc_inflight_timeout(struct obd_import *imp)
 242 {
 243         time64_t now = ktime_get_real_seconds();
 244         struct list_head *tmp, *n;
 245         struct ptlrpc_request *req;
 246         unsigned int timeout = 0;
 247
 248         spin_lock(&imp->imp_lock);
 249         list_for_each_safe(tmp, n, &imp->imp_sending_list) {
 250                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 251                 timeout = max(ptlrpc_inflight_deadline(req, now), timeout);
 252         }
 253         spin_unlock(&imp->imp_lock);
 254         return timeout;
 255 }
 256
 257 /**
 258  * This function will invalidate the import, if necessary, then block
 259  * for all the RPC completions, and finally notify the obd to
 260  * invalidate its state (ie cancel locks, clear pending requests,
 261  * etc).
 262  */
 263 void ptlrpc_invalidate_import(struct obd_import *imp)
 264 {
 265         struct list_head *tmp, *n;
 266         struct ptlrpc_request *req;
 267         struct l_wait_info lwi;
 268         unsigned int timeout;
 269         int rc;
 270
 271         atomic_inc(&imp->imp_inval_count);
 272
 273         if (!imp->imp_invalid || imp->imp_obd->obd_no_recov)
 274                 ptlrpc_deactivate_import(imp);
 275
 276         CFS_FAIL_TIMEOUT(OBD_FAIL_MGS_CONNECT_NET, 3 * cfs_fail_val / 2);
 277         LASSERT(imp->imp_invalid);
 278
 279         /* Wait forever until inflight == 0. We really can't do it another
 280          * way because in some cases we need to wait for very long reply
 281          * unlink. We can't do anything before that because there is really
 282          * no guarantee that some rdma transfer is not in progress right now.
 283          */
 284         do {
 285                 /* Calculate max timeout for waiting on rpcs to error
 286                  * out. Use obd_timeout if calculated value is smaller
 287                  * than it.
 288                  */
 289                 if (!OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_REPL_UNLINK)) {
 290                         timeout = ptlrpc_inflight_timeout(imp);
 291                         timeout += timeout / 3;
 292
 293                         if (timeout == 0)
 294                                 timeout = obd_timeout;
 295                 } else {
 296                         /* decrease the interval to increase race condition */
 297                         timeout = 1;
 298                 }
 299
 300                 CDEBUG(D_RPCTRACE,
 301                        "Sleeping %d sec for inflight to error out\n",
 302                        timeout);
 303
 304                 /* Wait for all requests to error out and call completion
 305                  * callbacks. Cap it at obd_timeout -- these should all
 306                  * have been locally cancelled by ptlrpc_abort_inflight.
 307                  */
 308                 lwi = LWI_TIMEOUT_INTERVAL(
 309                         cfs_timeout_cap(cfs_time_seconds(timeout)),
 310                         (timeout > 1) ? cfs_time_seconds(1) :
 311                         cfs_time_seconds(1) / 2,
 312                         NULL, NULL);
 313                 rc = l_wait_event(imp->imp_recovery_waitq,
 314                                   (atomic_read(&imp->imp_inflight) == 0),
 315                                   &lwi);
 316                 if (rc) {
 317                         const char *cli_tgt = obd2cli_tgt(imp->imp_obd);
 318
 319                         CERROR("%s: rc = %d waiting for callback (%d != 0)\n",
 320                                cli_tgt, rc,
 321                                atomic_read(&imp->imp_inflight));
 322
 323                         spin_lock(&imp->imp_lock);
 324                         if (atomic_read(&imp->imp_inflight) == 0) {
 325                                 int count = atomic_read(&imp->imp_unregistering);
 326
 327                                 /* We know that "unregistering" rpcs only can
 328                                  * survive in sending or delaying lists (they
 329                                  * maybe waiting for long reply unlink in
 330                                  * sluggish nets). Let's check this. If there
 331                                  * is no inflight and unregistering != 0, this
 332                                  * is bug.
 333                                  */
 334                                 LASSERTF(count == 0, "Some RPCs are still unregistering: %d\n",
 335                                          count);
 336
 337                                 /* Let's save one loop as soon as inflight have
 338                                  * dropped to zero. No new inflights possible at
 339                                  * this point.
 340                                  */
 341                                 rc = 0;
 342                         } else {
 343                                 list_for_each_safe(tmp, n,
 344                                                    &imp->imp_sending_list) {
 345                                         req = list_entry(tmp,
 346                                                          struct ptlrpc_request,
 347                                                          rq_list);
 348                                         DEBUG_REQ(D_ERROR, req,
 349                                                   "still on sending list");
 350                                 }
 351                                 list_for_each_safe(tmp, n,
 352                                                    &imp->imp_delayed_list) {
 353                                         req = list_entry(tmp,
 354                                                          struct ptlrpc_request,
 355                                                          rq_list);
 356                                         DEBUG_REQ(D_ERROR, req,
 357                                                   "still on delayed list");
 358                                 }
 359
 360                                 CERROR("%s: Unregistering RPCs found (%d). Network is sluggish? Waiting them to error out.\n",
 361                                        cli_tgt,
 362                                        atomic_read(&imp->
 363                                                    imp_unregistering));
 364                         }
 365                         spin_unlock(&imp->imp_lock);
 366                 }
 367         } while (rc != 0);
 368
 369         /*
 370          * Let's additionally check that no new rpcs added to import in
 371          * "invalidate" state.
 372          */
 373         LASSERT(atomic_read(&imp->imp_inflight) == 0);
 374         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
 375         sptlrpc_import_flush_all_ctx(imp);
 376
 377         atomic_dec(&imp->imp_inval_count);
 378         wake_up_all(&imp->imp_recovery_waitq);
 379 }
 380 EXPORT_SYMBOL(ptlrpc_invalidate_import);
 381
 382 /* unset imp_invalid */
 383 void ptlrpc_activate_import(struct obd_import *imp)
 384 {
 385         struct obd_device *obd = imp->imp_obd;
 386
 387         spin_lock(&imp->imp_lock);
 388         if (imp->imp_deactive != 0) {
 389                 spin_unlock(&imp->imp_lock);
 390                 return;
 391         }
 392
 393         imp->imp_invalid = 0;
 394         spin_unlock(&imp->imp_lock);
 395         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
 396 }
 397 EXPORT_SYMBOL(ptlrpc_activate_import);
 398
 399 void ptlrpc_pinger_force(struct obd_import *imp)
 400 {
 401         CDEBUG(D_HA, "%s: waking up pinger s:%s\n", obd2cli_tgt(imp->imp_obd),
 402                ptlrpc_import_state_name(imp->imp_state));
 403
 404         spin_lock(&imp->imp_lock);
 405         imp->imp_force_verify = 1;
 406         spin_unlock(&imp->imp_lock);
 407
 408         if (imp->imp_state != LUSTRE_IMP_CONNECTING)
 409                 ptlrpc_pinger_wake_up();
 410 }
 411 EXPORT_SYMBOL(ptlrpc_pinger_force);
 412
 413 void ptlrpc_fail_import(struct obd_import *imp, __u32 conn_cnt)
 414 {
 415         LASSERT(!imp->imp_dlm_fake);
 416
 417         if (ptlrpc_set_import_discon(imp, conn_cnt)) {
 418                 if (!imp->imp_replayable) {
 419                         CDEBUG(D_HA, "import %s@%s for %s not replayable, auto-deactivating\n",
 420                                obd2cli_tgt(imp->imp_obd),
 421                                imp->imp_connection->c_remote_uuid.uuid,
 422                                imp->imp_obd->obd_name);
 423                         ptlrpc_deactivate_import(imp);
 424                 }
 425
 426                 ptlrpc_pinger_force(imp);
 427         }
 428 }
 429
 430 int ptlrpc_reconnect_import(struct obd_import *imp)
 431 {
 432         struct l_wait_info lwi;
 433         int secs = cfs_time_seconds(obd_timeout);
 434         int rc;
 435
 436         ptlrpc_pinger_force(imp);
 437
 438         CDEBUG(D_HA, "%s: recovery started, waiting %u seconds\n",
 439                obd2cli_tgt(imp->imp_obd), secs);
 440
 441         lwi = LWI_TIMEOUT(secs, NULL, NULL);
 442         rc = l_wait_event(imp->imp_recovery_waitq,
 443                           !ptlrpc_import_in_recovery(imp), &lwi);
 444         CDEBUG(D_HA, "%s: recovery finished s:%s\n", obd2cli_tgt(imp->imp_obd),
 445                ptlrpc_import_state_name(imp->imp_state));
 446         return rc;
 447 }
 448 EXPORT_SYMBOL(ptlrpc_reconnect_import);
 449
 450 /**
 451  * Connection on import \a imp is changed to another one (if more than one is
 452  * present). We typically chose connection that we have not tried to connect to
 453  * the longest
 454  */
 455 static int import_select_connection(struct obd_import *imp)
 456 {
 457         struct obd_import_conn *imp_conn = NULL, *conn;
 458         struct obd_export *dlmexp;
 459         char *target_start;
 460         int target_len, tried_all = 1;
 461
 462         spin_lock(&imp->imp_lock);
 463
 464         if (list_empty(&imp->imp_conn_list)) {
 465                 CERROR("%s: no connections available\n",
 466                        imp->imp_obd->obd_name);
 467                 spin_unlock(&imp->imp_lock);
 468                 return -EINVAL;
 469         }
 470
 471         list_for_each_entry(conn, &imp->imp_conn_list, oic_item) {
 472                 CDEBUG(D_HA, "%s: connect to NID %s last attempt %llu\n",
 473                        imp->imp_obd->obd_name,
 474                        libcfs_nid2str(conn->oic_conn->c_peer.nid),
 475                        conn->oic_last_attempt);
 476
 477                 /* If we have not tried this connection since
 478                  * the last successful attempt, go with this one
 479                  */
 480                 if ((conn->oic_last_attempt == 0) ||
 481                     cfs_time_beforeq_64(conn->oic_last_attempt,
 482                                         imp->imp_last_success_conn)) {
 483                         imp_conn = conn;
 484                         tried_all = 0;
 485                         break;
 486                 }
 487
 488                 /* If all of the connections have already been tried
 489                  * since the last successful connection; just choose the
 490                  * least recently used
 491                  */
 492                 if (!imp_conn)
 493                         imp_conn = conn;
 494                 else if (cfs_time_before_64(conn->oic_last_attempt,
 495                                             imp_conn->oic_last_attempt))
 496                         imp_conn = conn;
 497         }
 498
 499         /* if not found, simply choose the current one */
 500         if (!imp_conn || imp->imp_force_reconnect) {
 501                 LASSERT(imp->imp_conn_current);
 502                 imp_conn = imp->imp_conn_current;
 503                 tried_all = 0;
 504         }
 505         LASSERT(imp_conn->oic_conn);
 506
 507         /* If we've tried everything, and we're back to the beginning of the
 508          * list, increase our timeout and try again. It will be reset when
 509          * we do finally connect. (FIXME: really we should wait for all network
 510          * state associated with the last connection attempt to drain before
 511          * trying to reconnect on it.)
 512          */
 513         if (tried_all && (imp->imp_conn_list.next == &imp_conn->oic_item)) {
 514                 struct adaptive_timeout *at = &imp->imp_at.iat_net_latency;
 515
 516                 if (at_get(at) < CONNECTION_SWITCH_MAX) {
 517                         at_measured(at, at_get(at) + CONNECTION_SWITCH_INC);
 518                         if (at_get(at) > CONNECTION_SWITCH_MAX)
 519                                 at_reset(at, CONNECTION_SWITCH_MAX);
 520                 }
 521                 LASSERT(imp_conn->oic_last_attempt);
 522                 CDEBUG(D_HA, "%s: tried all connections, increasing latency to %ds\n",
 523                        imp->imp_obd->obd_name, at_get(at));
 524         }
 525
 526         imp_conn->oic_last_attempt = cfs_time_current_64();
 527
 528         /* switch connection, don't mind if it's same as the current one */
 529         ptlrpc_connection_put(imp->imp_connection);
 530         imp->imp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 531
 532         dlmexp = class_conn2export(&imp->imp_dlm_handle);
 533         ptlrpc_connection_put(dlmexp->exp_connection);
 534         dlmexp->exp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 535         class_export_put(dlmexp);
 536
 537         if (imp->imp_conn_current != imp_conn) {
 538                 if (imp->imp_conn_current) {
 539                         deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
 540                                   &target_start, &target_len);
 541
 542                         CDEBUG(D_HA, "%s: Connection changing to %.*s (at %s)\n",
 543                                imp->imp_obd->obd_name,
 544                                target_len, target_start,
 545                                libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
 546                 }
 547
 548                 imp->imp_conn_current = imp_conn;
 549         }
 550
 551         CDEBUG(D_HA, "%s: import %p using connection %s/%s\n",
 552                imp->imp_obd->obd_name, imp, imp_conn->oic_uuid.uuid,
 553                libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
 554
 555         spin_unlock(&imp->imp_lock);
 556
 557         return 0;
 558 }
 559
 560 /*
 561  * must be called under imp_lock
 562  */
 563 static int ptlrpc_first_transno(struct obd_import *imp, __u64 *transno)
 564 {
 565         struct ptlrpc_request *req;
 566         struct list_head *tmp;
 567
 568         /* The requests in committed_list always have smaller transnos than
 569          * the requests in replay_list
 570          */
 571         if (!list_empty(&imp->imp_committed_list)) {
 572                 tmp = imp->imp_committed_list.next;
 573                 req = list_entry(tmp, struct ptlrpc_request, rq_replay_list);
 574                 *transno = req->rq_transno;
 575                 if (req->rq_transno == 0) {
 576                         DEBUG_REQ(D_ERROR, req,
 577                                   "zero transno in committed_list");
 578                         LBUG();
 579                 }
 580                 return 1;
 581         }
 582         if (!list_empty(&imp->imp_replay_list)) {
 583                 tmp = imp->imp_replay_list.next;
 584                 req = list_entry(tmp, struct ptlrpc_request, rq_replay_list);
 585                 *transno = req->rq_transno;
 586                 if (req->rq_transno == 0) {
 587                         DEBUG_REQ(D_ERROR, req, "zero transno in replay_list");
 588                         LBUG();
 589                 }
 590                 return 1;
 591         }
 592         return 0;
 593 }
 594
 595 /**
 596  * Attempt to (re)connect import \a imp. This includes all preparations,
 597  * initializing CONNECT RPC request and passing it to ptlrpcd for
 598  * actual sending.
 599  * Returns 0 on success or error code.
 600  */
 601 int ptlrpc_connect_import(struct obd_import *imp)
 602 {
 603         struct obd_device *obd = imp->imp_obd;
 604         int initial_connect = 0;
 605         int set_transno = 0;
 606         __u64 committed_before_reconnect = 0;
 607         struct ptlrpc_request *request;
 608         char *bufs[] = { NULL,
 609                          obd2cli_tgt(imp->imp_obd),
 610                          obd->obd_uuid.uuid,
 611                          (char *)&imp->imp_dlm_handle,
 612                          (char *)&imp->imp_connect_data };
 613         struct ptlrpc_connect_async_args *aa;
 614         int rc;
 615
 616         spin_lock(&imp->imp_lock);
 617         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 618                 spin_unlock(&imp->imp_lock);
 619                 CERROR("can't connect to a closed import\n");
 620                 return -EINVAL;
 621         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
 622                 spin_unlock(&imp->imp_lock);
 623                 CERROR("already connected\n");
 624                 return 0;
 625         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING ||
 626                    imp->imp_connected) {
 627                 spin_unlock(&imp->imp_lock);
 628                 CERROR("already connecting\n");
 629                 return -EALREADY;
 630         }
 631
 632         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CONNECTING);
 633
 634         imp->imp_conn_cnt++;
 635         imp->imp_resend_replay = 0;
 636
 637         if (!lustre_handle_is_used(&imp->imp_remote_handle))
 638                 initial_connect = 1;
 639         else
 640                 committed_before_reconnect = imp->imp_peer_committed_transno;
 641
 642         set_transno = ptlrpc_first_transno(imp,
 643                                            &imp->imp_connect_data.ocd_transno);
 644         spin_unlock(&imp->imp_lock);
 645
 646         rc = import_select_connection(imp);
 647         if (rc)
 648                 goto out;
 649
 650         rc = sptlrpc_import_sec_adapt(imp, NULL, NULL);
 651         if (rc)
 652                 goto out;
 653
 654         /* Reset connect flags to the originally requested flags, in case
 655          * the server is updated on-the-fly we will get the new features.
 656          */
 657         imp->imp_connect_data.ocd_connect_flags = imp->imp_connect_flags_orig;
 658         /* Reset ocd_version each time so the server knows the exact versions */
 659         imp->imp_connect_data.ocd_version = LUSTRE_VERSION_CODE;
 660         imp->imp_msghdr_flags &= ~MSGHDR_AT_SUPPORT;
 661         imp->imp_msghdr_flags &= ~MSGHDR_CKSUM_INCOMPAT18;
 662
 663         rc = obd_reconnect(NULL, imp->imp_obd->obd_self_export, obd,
 664                            &obd->obd_uuid, &imp->imp_connect_data, NULL);
 665         if (rc)
 666                 goto out;
 667
 668         request = ptlrpc_request_alloc(imp, &RQF_MDS_CONNECT);
 669         if (!request) {
 670                 rc = -ENOMEM;
 671                 goto out;
 672         }
 673
 674         rc = ptlrpc_request_bufs_pack(request, LUSTRE_OBD_VERSION,
 675                                       imp->imp_connect_op, bufs, NULL);
 676         if (rc) {
 677                 ptlrpc_request_free(request);
 678                 goto out;
 679         }
 680
 681         /* Report the rpc service time to the server so that it knows how long
 682          * to wait for clients to join recovery
 683          */
 684         lustre_msg_set_service_time(request->rq_reqmsg,
 685                                     at_timeout2est(request->rq_timeout));
 686
 687         /* The amount of time we give the server to process the connect req.
 688          * import_select_connection will increase the net latency on
 689          * repeated reconnect attempts to cover slow networks.
 690          * We override/ignore the server rpc completion estimate here,
 691          * which may be large if this is a reconnect attempt
 692          */
 693         request->rq_timeout = INITIAL_CONNECT_TIMEOUT;
 694         lustre_msg_set_timeout(request->rq_reqmsg, request->rq_timeout);
 695
 696         request->rq_no_resend = 1;
 697         request->rq_no_delay = 1;
 698         request->rq_send_state = LUSTRE_IMP_CONNECTING;
 699         /* Allow a slightly larger reply for future growth compatibility */
 700         req_capsule_set_size(&request->rq_pill, &RMF_CONNECT_DATA, RCL_SERVER,
 701                              sizeof(struct obd_connect_data) +
 702                              16 * sizeof(__u64));
 703         ptlrpc_request_set_replen(request);
 704         request->rq_interpret_reply = ptlrpc_connect_interpret;
 705
 706         BUILD_BUG_ON(sizeof(*aa) > sizeof(request->rq_async_args));
 707         aa = ptlrpc_req_async_args(request);
 708         memset(aa, 0, sizeof(*aa));
 709
 710         aa->pcaa_peer_committed = committed_before_reconnect;
 711         aa->pcaa_initial_connect = initial_connect;
 712
 713         if (aa->pcaa_initial_connect) {
 714                 spin_lock(&imp->imp_lock);
 715                 imp->imp_replayable = 1;
 716                 spin_unlock(&imp->imp_lock);
 717                 lustre_msg_add_op_flags(request->rq_reqmsg,
 718                                         MSG_CONNECT_INITIAL);
 719         }
 720
 721         if (set_transno)
 722                 lustre_msg_add_op_flags(request->rq_reqmsg,
 723                                         MSG_CONNECT_TRANSNO);
 724
 725         DEBUG_REQ(D_RPCTRACE, request, "(re)connect request (timeout %d)",
 726                   request->rq_timeout);
 727         ptlrpcd_add_req(request);
 728         rc = 0;
 729 out:
 730         if (rc != 0)
 731                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 732
 733         return rc;
 734 }
 735 EXPORT_SYMBOL(ptlrpc_connect_import);
 736
 737 static void ptlrpc_maybe_ping_import_soon(struct obd_import *imp)
 738 {
 739         int force_verify;
 740
 741         spin_lock(&imp->imp_lock);
 742         force_verify = imp->imp_force_verify != 0;
 743         spin_unlock(&imp->imp_lock);
 744
 745         if (force_verify)
 746                 ptlrpc_pinger_wake_up();
 747 }
 748
 749 static int ptlrpc_busy_reconnect(int rc)
 750 {
 751         return (rc == -EBUSY) || (rc == -EAGAIN);
 752 }
 753
 754 static int ptlrpc_connect_set_flags(struct obd_import *imp,
 755                                     struct obd_connect_data *ocd,
 756                                     u64 old_connect_flags,
 757                                     struct obd_export *exp, int init_connect)
 758 {
 759         struct client_obd *cli = &imp->imp_obd->u.cli;
 760         static bool warned;
 761
 762         if ((imp->imp_connect_flags_orig & OBD_CONNECT_IBITS) &&
 763             !(ocd->ocd_connect_flags & OBD_CONNECT_IBITS)) {
 764                 LCONSOLE_WARN("%s: MDS %s does not support ibits lock, either very old or invalid: requested %#llx, replied %#llx\n",
 765                               imp->imp_obd->obd_name,
 766                               imp->imp_connection->c_remote_uuid.uuid,
 767                               imp->imp_connect_flags_orig,
 768                               ocd->ocd_connect_flags);
 769                 return -EPROTO;
 770         }
 771
 772         spin_lock(&imp->imp_lock);
 773         list_del(&imp->imp_conn_current->oic_item);
 774         list_add(&imp->imp_conn_current->oic_item, &imp->imp_conn_list);
 775         imp->imp_last_success_conn = imp->imp_conn_current->oic_last_attempt;
 776
 777         spin_unlock(&imp->imp_lock);
 778
 779         if (!warned && (ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
 780             (ocd->ocd_version > LUSTRE_VERSION_CODE +
 781                                 LUSTRE_VERSION_OFFSET_WARN ||
 782              ocd->ocd_version < LUSTRE_VERSION_CODE -
 783                                 LUSTRE_VERSION_OFFSET_WARN)) {
 784                 /*
 785                  * Sigh, some compilers do not like #ifdef in the middle
 786                  * of macro arguments
 787                  */
 788                 const char *older = "older than client. Consider upgrading server";
 789                 const char *newer = "newer than client. Consider recompiling application";
 790
 791                 LCONSOLE_WARN("Server %s version (%d.%d.%d.%d) is much %s (%s)\n",
 792                               obd2cli_tgt(imp->imp_obd),
 793                               OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
 794                               OBD_OCD_VERSION_MINOR(ocd->ocd_version),
 795                               OBD_OCD_VERSION_PATCH(ocd->ocd_version),
 796                               OBD_OCD_VERSION_FIX(ocd->ocd_version),
 797                               ocd->ocd_version > LUSTRE_VERSION_CODE ?
 798                               newer : older, LUSTRE_VERSION_STRING);
 799                 warned = true;
 800         }
 801
 802 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 0, 53, 0)
 803         /*
 804          * Check if server has LU-1252 fix applied to not always swab
 805          * the IR MNE entries. Do this only once per connection.  This
 806          * fixup is version-limited, because we don't want to carry the
 807          * OBD_CONNECT_MNE_SWAB flag around forever, just so long as we
 808          * need interop with unpatched 2.2 servers.  For newer servers,
 809          * the client will do MNE swabbing only as needed.  LU-1644
 810          */
 811         if (unlikely((ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
 812                      !(ocd->ocd_connect_flags & OBD_CONNECT_MNE_SWAB) &&
 813                      OBD_OCD_VERSION_MAJOR(ocd->ocd_version) == 2 &&
 814                      OBD_OCD_VERSION_MINOR(ocd->ocd_version) == 2 &&
 815                      OBD_OCD_VERSION_PATCH(ocd->ocd_version) < 55 &&
 816                      !strcmp(imp->imp_obd->obd_type->typ_name,
 817                              LUSTRE_MGC_NAME)))
 818                 imp->imp_need_mne_swab = 1;
 819         else /* clear if server was upgraded since last connect */
 820                 imp->imp_need_mne_swab = 0;
 821 #endif
 822
 823         if (ocd->ocd_connect_flags & OBD_CONNECT_CKSUM) {
 824                 /*
 825                  * We sent to the server ocd_cksum_types with bits set
 826                  * for algorithms we understand. The server masked off
 827                  * the checksum types it doesn't support
 828                  */
 829                 if (!(ocd->ocd_cksum_types & cksum_types_supported_client())) {
 830                         LCONSOLE_WARN("The negotiation of the checksum algorithm to use with server %s failed (%x/%x), disabling checksums\n",
 831                                       obd2cli_tgt(imp->imp_obd),
 832                                       ocd->ocd_cksum_types,
 833                                       cksum_types_supported_client());
 834                         cli->cl_checksum = 0;
 835                         cli->cl_supp_cksum_types = OBD_CKSUM_ADLER;
 836                 } else {
 837                         cli->cl_supp_cksum_types = ocd->ocd_cksum_types;
 838                 }
 839         } else {
 840                 /*
 841                  * The server does not support OBD_CONNECT_CKSUM.
 842                  * Enforce ADLER for backward compatibility
 843                  */
 844                 cli->cl_supp_cksum_types = OBD_CKSUM_ADLER;
 845         }
 846         cli->cl_cksum_type = cksum_type_select(cli->cl_supp_cksum_types);
 847
 848         if (ocd->ocd_connect_flags & OBD_CONNECT_BRW_SIZE)
 849                 cli->cl_max_pages_per_rpc =
 850                         min(ocd->ocd_brw_size >> PAGE_SHIFT,
 851                             cli->cl_max_pages_per_rpc);
 852         else if (imp->imp_connect_op == MDS_CONNECT ||
 853                  imp->imp_connect_op == MGS_CONNECT)
 854                 cli->cl_max_pages_per_rpc = 1;
 855
 856         LASSERT((cli->cl_max_pages_per_rpc <= PTLRPC_MAX_BRW_PAGES) &&
 857                 (cli->cl_max_pages_per_rpc > 0));
 858
 859         client_adjust_max_dirty(cli);
 860
 861         /*
 862          * Update client max modify RPCs in flight with value returned
 863          * by the server
 864          */
 865         if (ocd->ocd_connect_flags & OBD_CONNECT_MULTIMODRPCS)
 866                 cli->cl_max_mod_rpcs_in_flight = min(
 867                                         cli->cl_max_mod_rpcs_in_flight,
 868                                         ocd->ocd_maxmodrpcs);
 869         else
 870                 cli->cl_max_mod_rpcs_in_flight = 1;
 871
 872         /*
 873          * Reset ns_connect_flags only for initial connect. It might be
 874          * changed in while using FS and if we reset it in reconnect
 875          * this leads to losing user settings done before such as
 876          * disable lru_resize, etc.
 877          */
 878         if (old_connect_flags != exp_connect_flags(exp) || init_connect) {
 879                 CDEBUG(D_HA, "%s: Resetting ns_connect_flags to server flags: %#llx\n",
 880                        imp->imp_obd->obd_name, ocd->ocd_connect_flags);
 881                 imp->imp_obd->obd_namespace->ns_connect_flags =
 882                         ocd->ocd_connect_flags;
 883                 imp->imp_obd->obd_namespace->ns_orig_connect_flags =
 884                         ocd->ocd_connect_flags;
 885         }
 886
 887         if (ocd->ocd_connect_flags & OBD_CONNECT_AT)
 888                 /*
 889                  * We need a per-message support flag, because
 890                  * a. we don't know if the incoming connect reply
 891                  *    supports AT or not (in reply_in_callback)
 892                  *    until we unpack it.
 893                  * b. failovered server means export and flags are gone
 894                  *    (in ptlrpc_send_reply).
 895                  *    Can only be set when we know AT is supported at
 896                  *    both ends
 897                  */
 898                 imp->imp_msghdr_flags |= MSGHDR_AT_SUPPORT;
 899         else
 900                 imp->imp_msghdr_flags &= ~MSGHDR_AT_SUPPORT;
 901
 902         imp->imp_msghdr_flags |= MSGHDR_CKSUM_INCOMPAT18;
 903
 904         return 0;
 905 }
 906
 907 /**
 908  * Add all replay requests back to unreplied list before start replay,
 909  * so that we can make sure the known replied XID is always increased
 910  * only even if when replaying requests.
 911  */
 912 static void ptlrpc_prepare_replay(struct obd_import *imp)
 913 {
 914         struct ptlrpc_request *req;
 915
 916         if (imp->imp_state != LUSTRE_IMP_REPLAY ||
 917             imp->imp_resend_replay)
 918                 return;
 919
 920         /*
 921          * If the server was restart during repaly, the requests may
 922          * have been added to the unreplied list in former replay.
 923          */
 924         spin_lock(&imp->imp_lock);
 925
 926         list_for_each_entry(req, &imp->imp_committed_list, rq_replay_list) {
 927                 if (list_empty(&req->rq_unreplied_list))
 928                         ptlrpc_add_unreplied(req);
 929         }
 930
 931         list_for_each_entry(req, &imp->imp_replay_list, rq_replay_list) {
 932                 if (list_empty(&req->rq_unreplied_list))
 933                         ptlrpc_add_unreplied(req);
 934         }
 935
 936         imp->imp_known_replied_xid = ptlrpc_known_replied_xid(imp);
 937         spin_unlock(&imp->imp_lock);
 938 }
 939
 940 /**
 941  * interpret_reply callback for connect RPCs.
 942  * Looks into returned status of connect operation and decides
 943  * what to do with the import - i.e enter recovery, promote it to
 944  * full state for normal operations of disconnect it due to an error.
 945  */
 946 static int ptlrpc_connect_interpret(const struct lu_env *env,
 947                                     struct ptlrpc_request *request,
 948                                     void *data, int rc)
 949 {
 950         struct ptlrpc_connect_async_args *aa = data;
 951         struct obd_import *imp = request->rq_import;
 952         struct lustre_handle old_hdl;
 953         __u64 old_connect_flags;
 954         int msg_flags;
 955         struct obd_connect_data *ocd;
 956         struct obd_export *exp;
 957         int ret;
 958
 959         spin_lock(&imp->imp_lock);
 960         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 961                 imp->imp_connect_tried = 1;
 962                 spin_unlock(&imp->imp_lock);
 963                 return 0;
 964         }
 965
 966         if (rc) {
 967                 /* if this reconnect to busy export - not need select new target
 968                  * for connecting
 969                  */
 970                 imp->imp_force_reconnect = ptlrpc_busy_reconnect(rc);
 971                 spin_unlock(&imp->imp_lock);
 972                 ptlrpc_maybe_ping_import_soon(imp);
 973                 goto out;
 974         }
 975
 976         /*
 977          * LU-7558: indicate that we are interpretting connect reply,
 978          * pltrpc_connect_import() will not try to reconnect until
 979          * interpret will finish.
 980          */
 981         imp->imp_connected = 1;
 982         spin_unlock(&imp->imp_lock);
 983
 984         LASSERT(imp->imp_conn_current);
 985
 986         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
 987
 988         ret = req_capsule_get_size(&request->rq_pill, &RMF_CONNECT_DATA,
 989                                    RCL_SERVER);
 990         /* server replied obd_connect_data is always bigger */
 991         ocd = req_capsule_server_sized_get(&request->rq_pill,
 992                                            &RMF_CONNECT_DATA, ret);
 993
 994         if (!ocd) {
 995                 CERROR("%s: no connect data from server\n",
 996                        imp->imp_obd->obd_name);
 997                 rc = -EPROTO;
 998                 goto out;
 999         }
1000
1001         spin_lock(&imp->imp_lock);
1002
1003         /* All imports are pingable */
1004         imp->imp_pingable = 1;
1005         imp->imp_force_reconnect = 0;
1006         imp->imp_force_verify = 0;
1007
1008         imp->imp_connect_data = *ocd;
1009
1010         CDEBUG(D_HA, "%s: connect to target with instance %u\n",
1011                imp->imp_obd->obd_name, ocd->ocd_instance);
1012         exp = class_conn2export(&imp->imp_dlm_handle);
1013
1014         spin_unlock(&imp->imp_lock);
1015
1016         if (!exp) {
1017                 /* This could happen if export is cleaned during the
1018                  * connect attempt
1019                  */
1020                 CERROR("%s: missing export after connect\n",
1021                        imp->imp_obd->obd_name);
1022                 rc = -ENODEV;
1023                 goto out;
1024         }
1025
1026         /* check that server granted subset of flags we asked for. */
1027         if ((ocd->ocd_connect_flags & imp->imp_connect_flags_orig) !=
1028             ocd->ocd_connect_flags) {
1029                 CERROR("%s: Server didn't grant the asked for subset of flags: asked=%#llx granted=%#llx\n",
1030                        imp->imp_obd->obd_name, imp->imp_connect_flags_orig,
1031                        ocd->ocd_connect_flags);
1032                 rc = -EPROTO;
1033                 goto out;
1034         }
1035
1036         old_connect_flags = exp_connect_flags(exp);
1037         exp->exp_connect_data = *ocd;
1038         imp->imp_obd->obd_self_export->exp_connect_data = *ocd;
1039
1040         /*
1041          * The net statistics after (re-)connect is not valid anymore,
1042          * because may reflect other routing, etc.
1043          */
1044         at_init(&imp->imp_at.iat_net_latency, 0, 0);
1045         ptlrpc_at_adj_net_latency(request,
1046                                   lustre_msg_get_service_time(request->rq_repmsg));
1047
1048         /* Import flags should be updated before waking import at FULL state */
1049         rc = ptlrpc_connect_set_flags(imp, ocd, old_connect_flags, exp,
1050                                       aa->pcaa_initial_connect);
1051         class_export_put(exp);
1052         if (rc)
1053                 goto out;
1054
1055         obd_import_event(imp->imp_obd, imp, IMP_EVENT_OCD);
1056
1057         if (aa->pcaa_initial_connect) {
1058                 spin_lock(&imp->imp_lock);
1059                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
1060                         imp->imp_replayable = 1;
1061                         spin_unlock(&imp->imp_lock);
1062                         CDEBUG(D_HA, "connected to replayable target: %s\n",
1063                                obd2cli_tgt(imp->imp_obd));
1064                 } else {
1065                         imp->imp_replayable = 0;
1066                         spin_unlock(&imp->imp_lock);
1067                 }
1068
1069                 /* if applies, adjust the imp->imp_msg_magic here
1070                  * according to reply flags
1071                  */
1072
1073                 imp->imp_remote_handle =
1074                                 *lustre_msg_get_handle(request->rq_repmsg);
1075
1076                 /* Initial connects are allowed for clients with non-random
1077                  * uuids when servers are in recovery.  Simply signal the
1078                  * servers replay is complete and wait in REPLAY_WAIT.
1079                  */
1080                 if (msg_flags & MSG_CONNECT_RECOVERING) {
1081                         CDEBUG(D_HA, "connect to %s during recovery\n",
1082                                obd2cli_tgt(imp->imp_obd));
1083                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
1084                 } else {
1085                         IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
1086                         ptlrpc_activate_import(imp);
1087                 }
1088
1089                 rc = 0;
1090                 goto finish;
1091         }
1092
1093         /* Determine what recovery state to move the import to. */
1094         if (msg_flags & MSG_CONNECT_RECONNECT) {
1095                 memset(&old_hdl, 0, sizeof(old_hdl));
1096                 if (!memcmp(&old_hdl, lustre_msg_get_handle(request->rq_repmsg),
1097                             sizeof(old_hdl))) {
1098                         LCONSOLE_WARN("Reconnect to %s (at @%s) failed due bad handle %#llx\n",
1099                                       obd2cli_tgt(imp->imp_obd),
1100                                       imp->imp_connection->c_remote_uuid.uuid,
1101                                       imp->imp_dlm_handle.cookie);
1102                         rc = -ENOTCONN;
1103                         goto out;
1104                 }
1105
1106                 if (memcmp(&imp->imp_remote_handle,
1107                            lustre_msg_get_handle(request->rq_repmsg),
1108                            sizeof(imp->imp_remote_handle))) {
1109                         int level = msg_flags & MSG_CONNECT_RECOVERING ?
1110                                 D_HA : D_WARNING;
1111
1112                         /* Bug 16611/14775: if server handle have changed,
1113                          * that means some sort of disconnection happened.
1114                          * If the server is not in recovery, that also means it
1115                          * already erased all of our state because of previous
1116                          * eviction. If it is in recovery - we are safe to
1117                          * participate since we can reestablish all of our state
1118                          * with server again
1119                          */
1120                         if ((msg_flags & MSG_CONNECT_RECOVERING)) {
1121                                 CDEBUG(level, "%s@%s changed server handle from %#llx to %#llx but is still in recovery\n",
1122                                        obd2cli_tgt(imp->imp_obd),
1123                                        imp->imp_connection->c_remote_uuid.uuid,
1124                                        imp->imp_remote_handle.cookie,
1125                                        lustre_msg_get_handle(
1126                                        request->rq_repmsg)->cookie);
1127                         } else {
1128                                 LCONSOLE_WARN("Evicted from %s (at %s) after server handle changed from %#llx to %#llx\n",
1129                                               obd2cli_tgt(imp->imp_obd),
1130                                               imp->imp_connection-> \
1131                                               c_remote_uuid.uuid,
1132                                               imp->imp_remote_handle.cookie,
1133                                               lustre_msg_get_handle(
1134                                                       request->rq_repmsg)->cookie);
1135                         }
1136
1137                         imp->imp_remote_handle =
1138                                      *lustre_msg_get_handle(request->rq_repmsg);
1139
1140                         if (!(msg_flags & MSG_CONNECT_RECOVERING)) {
1141                                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
1142                                 rc = 0;
1143                                 goto finish;
1144                         }
1145
1146                 } else {
1147                         CDEBUG(D_HA, "reconnected to %s@%s after partition\n",
1148                                obd2cli_tgt(imp->imp_obd),
1149                                imp->imp_connection->c_remote_uuid.uuid);
1150                 }
1151
1152                 if (imp->imp_invalid) {
1153                         CDEBUG(D_HA, "%s: reconnected but import is invalid; marking evicted\n",
1154                                imp->imp_obd->obd_name);
1155                         IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
1156                 } else if (msg_flags & MSG_CONNECT_RECOVERING) {
1157                         CDEBUG(D_HA, "%s: reconnected to %s during replay\n",
1158                                imp->imp_obd->obd_name,
1159                                obd2cli_tgt(imp->imp_obd));
1160
1161                         spin_lock(&imp->imp_lock);
1162                         imp->imp_resend_replay = 1;
1163                         spin_unlock(&imp->imp_lock);
1164
1165                         IMPORT_SET_STATE(imp, imp->imp_replay_state);
1166                 } else {
1167                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
1168                 }
1169         } else if ((msg_flags & MSG_CONNECT_RECOVERING) && !imp->imp_invalid) {
1170                 LASSERT(imp->imp_replayable);
1171                 imp->imp_remote_handle =
1172                                 *lustre_msg_get_handle(request->rq_repmsg);
1173                 imp->imp_last_replay_transno = 0;
1174                 imp->imp_replay_cursor = &imp->imp_committed_list;
1175                 IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
1176         } else {
1177                 DEBUG_REQ(D_HA, request, "%s: evicting (reconnect/recover flags not set: %x)",
1178                           imp->imp_obd->obd_name, msg_flags);
1179                 imp->imp_remote_handle =
1180                                 *lustre_msg_get_handle(request->rq_repmsg);
1181                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
1182         }
1183
1184         /* Sanity checks for a reconnected import. */
1185         if (!(imp->imp_replayable) != !(msg_flags & MSG_CONNECT_REPLAYABLE))
1186                 CERROR("imp_replayable flag does not match server after reconnect. We should LBUG right here.\n");
1187
1188         if (lustre_msg_get_last_committed(request->rq_repmsg) > 0 &&
1189             lustre_msg_get_last_committed(request->rq_repmsg) <
1190             aa->pcaa_peer_committed)
1191                 CERROR("%s went back in time (transno %lld was previously committed, server now claims %lld)!  See https://bugzilla.lustre.org/show_bug.cgi?id=9646\n",
1192                        obd2cli_tgt(imp->imp_obd), aa->pcaa_peer_committed,
1193                        lustre_msg_get_last_committed(request->rq_repmsg));
1194
1195 finish:
1196         ptlrpc_prepare_replay(imp);
1197         rc = ptlrpc_import_recovery_state_machine(imp);
1198         if (rc == -ENOTCONN) {
1199                 CDEBUG(D_HA, "evicted/aborted by %s@%s during recovery; invalidating and reconnecting\n",
1200                        obd2cli_tgt(imp->imp_obd),
1201                        imp->imp_connection->c_remote_uuid.uuid);
1202                 ptlrpc_connect_import(imp);
1203                 spin_lock(&imp->imp_lock);
1204                 imp->imp_connected = 0;
1205                 imp->imp_connect_tried = 1;
1206                 spin_unlock(&imp->imp_lock);
1207                 return 0;
1208         }
1209
1210 out:
1211         spin_lock(&imp->imp_lock);
1212         imp->imp_connected = 0;
1213         imp->imp_connect_tried = 1;
1214         spin_unlock(&imp->imp_lock);
1215
1216         if (rc != 0) {
1217                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
1218                 if (rc == -EACCES) {
1219                         /*
1220                          * Give up trying to reconnect
1221                          * EACCES means client has no permission for connection
1222                          */
1223                         imp->imp_obd->obd_no_recov = 1;
1224                         ptlrpc_deactivate_import(imp);
1225                 }
1226
1227                 if (rc == -EPROTO) {
1228                         struct obd_connect_data *ocd;
1229
1230                         /* reply message might not be ready */
1231                         if (!request->rq_repmsg)
1232                                 return -EPROTO;
1233
1234                         ocd = req_capsule_server_get(&request->rq_pill,
1235                                                      &RMF_CONNECT_DATA);
1236                         if (ocd &&
1237                             (ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
1238                             (ocd->ocd_version != LUSTRE_VERSION_CODE)) {
1239                                 /*
1240                                  * Actually servers are only supposed to refuse
1241                                  * connection from liblustre clients, so we
1242                                  * should never see this from VFS context
1243                                  */
1244                                 LCONSOLE_ERROR_MSG(0x16a, "Server %s version (%d.%d.%d.%d) refused connection from this client with an incompatible version (%s).  Client must be recompiled\n",
1245                                                    obd2cli_tgt(imp->imp_obd),
1246                                                    OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
1247                                                    OBD_OCD_VERSION_MINOR(ocd->ocd_version),
1248                                                    OBD_OCD_VERSION_PATCH(ocd->ocd_version),
1249                                                    OBD_OCD_VERSION_FIX(ocd->ocd_version),
1250                                                    LUSTRE_VERSION_STRING);
1251                                 ptlrpc_deactivate_import(imp);
1252                                 IMPORT_SET_STATE(imp, LUSTRE_IMP_CLOSED);
1253                         }
1254                         return -EPROTO;
1255                 }
1256
1257                 ptlrpc_maybe_ping_import_soon(imp);
1258
1259                 CDEBUG(D_HA, "recovery of %s on %s failed (%d)\n",
1260                        obd2cli_tgt(imp->imp_obd),
1261                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
1262         }
1263
1264         wake_up_all(&imp->imp_recovery_waitq);
1265         return rc;
1266 }
1267
1268 /**
1269  * interpret callback for "completed replay" RPCs.
1270  * \see signal_completed_replay
1271  */
1272 static int completed_replay_interpret(const struct lu_env *env,
1273                                       struct ptlrpc_request *req,
1274                                       void *data, int rc)
1275 {
1276         atomic_dec(&req->rq_import->imp_replay_inflight);
1277         if (req->rq_status == 0 &&
1278             !req->rq_import->imp_vbr_failed) {
1279                 ptlrpc_import_recovery_state_machine(req->rq_import);
1280         } else {
1281                 if (req->rq_import->imp_vbr_failed) {
1282                         CDEBUG(D_WARNING,
1283                                "%s: version recovery fails, reconnecting\n",
1284                                req->rq_import->imp_obd->obd_name);
1285                 } else {
1286                         CDEBUG(D_HA, "%s: LAST_REPLAY message error: %d, reconnecting\n",
1287                                req->rq_import->imp_obd->obd_name,
1288                                req->rq_status);
1289                 }
1290                 ptlrpc_connect_import(req->rq_import);
1291         }
1292
1293         return 0;
1294 }
1295
1296 /**
1297  * Let server know that we have no requests to replay anymore.
1298  * Achieved by just sending a PING request
1299  */
1300 static int signal_completed_replay(struct obd_import *imp)
1301 {
1302         struct ptlrpc_request *req;
1303
1304         if (unlikely(OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_FINISH_REPLAY)))
1305                 return 0;
1306
1307         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
1308         atomic_inc(&imp->imp_replay_inflight);
1309
1310         req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING, LUSTRE_OBD_VERSION,
1311                                         OBD_PING);
1312         if (!req) {
1313                 atomic_dec(&imp->imp_replay_inflight);
1314                 return -ENOMEM;
1315         }
1316
1317         ptlrpc_request_set_replen(req);
1318         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
1319         lustre_msg_add_flags(req->rq_reqmsg,
1320                              MSG_LOCK_REPLAY_DONE | MSG_REQ_REPLAY_DONE);
1321         if (AT_OFF)
1322                 req->rq_timeout *= 3;
1323         req->rq_interpret_reply = completed_replay_interpret;
1324
1325         ptlrpcd_add_req(req);
1326         return 0;
1327 }
1328
1329 /**
1330  * In kernel code all import invalidation happens in its own
1331  * separate thread, so that whatever application happened to encounter
1332  * a problem could still be killed or otherwise continue
1333  */
1334 static int ptlrpc_invalidate_import_thread(void *data)
1335 {
1336         struct obd_import *imp = data;
1337
1338         unshare_fs_struct();
1339
1340         CDEBUG(D_HA, "thread invalidate import %s to %s@%s\n",
1341                imp->imp_obd->obd_name, obd2cli_tgt(imp->imp_obd),
1342                imp->imp_connection->c_remote_uuid.uuid);
1343
1344         ptlrpc_invalidate_import(imp);
1345
1346         if (obd_dump_on_eviction) {
1347                 CERROR("dump the log upon eviction\n");
1348                 libcfs_debug_dumplog();
1349         }
1350
1351         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
1352         ptlrpc_import_recovery_state_machine(imp);
1353
1354         class_import_put(imp);
1355         return 0;
1356 }
1357
1358 /**
1359  * This is the state machine for client-side recovery on import.
1360  *
1361  * Typically we have two possibly paths. If we came to server and it is not
1362  * in recovery, we just enter IMP_EVICTED state, invalidate our import
1363  * state and reconnect from scratch.
1364  * If we came to server that is in recovery, we enter IMP_REPLAY import state.
1365  * We go through our list of requests to replay and send them to server one by
1366  * one.
1367  * After sending all request from the list we change import state to
1368  * IMP_REPLAY_LOCKS and re-request all the locks we believe we have from server
1369  * and also all the locks we don't yet have and wait for server to grant us.
1370  * After that we send a special "replay completed" request and change import
1371  * state to IMP_REPLAY_WAIT.
1372  * Upon receiving reply to that "replay completed" RPC we enter IMP_RECOVER
1373  * state and resend all requests from sending list.
1374  * After that we promote import to FULL state and send all delayed requests
1375  * and import is fully operational after that.
1376  *
1377  */
1378 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
1379 {
1380         int rc = 0;
1381         int inflight;
1382         char *target_start;
1383         int target_len;
1384
1385         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
1386                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
1387                           &target_start, &target_len);
1388                 /* Don't care about MGC eviction */
1389                 if (strcmp(imp->imp_obd->obd_type->typ_name,
1390                            LUSTRE_MGC_NAME) != 0) {
1391                         LCONSOLE_ERROR_MSG(0x167, "%s: This client was evicted by %.*s; in progress operations using this service will fail.\n",
1392                                            imp->imp_obd->obd_name, target_len,
1393                                            target_start);
1394                 }
1395                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
1396                        obd2cli_tgt(imp->imp_obd),
1397                        imp->imp_connection->c_remote_uuid.uuid);
1398                 /* reset vbr_failed flag upon eviction */
1399                 spin_lock(&imp->imp_lock);
1400                 imp->imp_vbr_failed = 0;
1401                 spin_unlock(&imp->imp_lock);
1402
1403                 {
1404                 struct task_struct *task;
1405                 /* bug 17802:  XXX client_disconnect_export vs connect request
1406                  * race. if client is evicted at this time, we start
1407                  * invalidate thread without reference to import and import can
1408                  * be freed at same time.
1409                  */
1410                 class_import_get(imp);
1411                 task = kthread_run(ptlrpc_invalidate_import_thread, imp,
1412                                    "ll_imp_inval");
1413                 if (IS_ERR(task)) {
1414                         class_import_put(imp);
1415                         CERROR("error starting invalidate thread: %d\n", rc);
1416                         rc = PTR_ERR(task);
1417                 } else {
1418                         rc = 0;
1419                 }
1420                 return rc;
1421                 }
1422         }
1423
1424         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
1425                 CDEBUG(D_HA, "replay requested by %s\n",
1426                        obd2cli_tgt(imp->imp_obd));
1427                 rc = ptlrpc_replay_next(imp, &inflight);
1428                 if (inflight == 0 &&
1429                     atomic_read(&imp->imp_replay_inflight) == 0) {
1430                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
1431                         rc = ldlm_replay_locks(imp);
1432                         if (rc)
1433                                 goto out;
1434                 }
1435                 rc = 0;
1436         }
1437
1438         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS)
1439                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
1440                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_WAIT);
1441                         rc = signal_completed_replay(imp);
1442                         if (rc)
1443                                 goto out;
1444                 }
1445
1446         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT)
1447                 if (atomic_read(&imp->imp_replay_inflight) == 0)
1448                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
1449
1450         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
1451                 CDEBUG(D_HA, "reconnected to %s@%s\n",
1452                        obd2cli_tgt(imp->imp_obd),
1453                        imp->imp_connection->c_remote_uuid.uuid);
1454
1455                 rc = ptlrpc_resend(imp);
1456                 if (rc)
1457                         goto out;
1458                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
1459                 ptlrpc_activate_import(imp);
1460
1461                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
1462                           &target_start, &target_len);
1463                 LCONSOLE_INFO("%s: Connection restored to %.*s (at %s)\n",
1464                               imp->imp_obd->obd_name,
1465                               target_len, target_start,
1466                               libcfs_nid2str(imp->imp_connection->c_peer.nid));
1467         }
1468
1469         if (imp->imp_state == LUSTRE_IMP_FULL) {
1470                 wake_up_all(&imp->imp_recovery_waitq);
1471                 ptlrpc_wake_delayed(imp);
1472         }
1473
1474 out:
1475         return rc;
1476 }
1477
1478 int ptlrpc_disconnect_import(struct obd_import *imp, int noclose)
1479 {
1480         struct ptlrpc_request *req;
1481         int rq_opc, rc = 0;
1482
1483         if (imp->imp_obd->obd_force)
1484                 goto set_state;
1485
1486         switch (imp->imp_connect_op) {
1487         case OST_CONNECT:
1488                 rq_opc = OST_DISCONNECT;
1489                 break;
1490         case MDS_CONNECT:
1491                 rq_opc = MDS_DISCONNECT;
1492                 break;
1493         case MGS_CONNECT:
1494                 rq_opc = MGS_DISCONNECT;
1495                 break;
1496         default:
1497                 rc = -EINVAL;
1498                 CERROR("%s: don't know how to disconnect from %s (connect_op %d): rc = %d\n",
1499                        imp->imp_obd->obd_name, obd2cli_tgt(imp->imp_obd),
1500                        imp->imp_connect_op, rc);
1501                 return rc;
1502         }
1503
1504         if (ptlrpc_import_in_recovery(imp)) {
1505                 struct l_wait_info lwi;
1506                 long timeout;
1507
1508                 if (AT_OFF) {
1509                         if (imp->imp_server_timeout)
1510                                 timeout = cfs_time_seconds(obd_timeout / 2);
1511                         else
1512                                 timeout = cfs_time_seconds(obd_timeout);
1513                 } else {
1514                         int idx = import_at_get_index(imp,
1515                                 imp->imp_client->cli_request_portal);
1516                         timeout = cfs_time_seconds(
1517                                 at_get(&imp->imp_at.iat_service_estimate[idx]));
1518                 }
1519
1520                 lwi = LWI_TIMEOUT_INTR(cfs_timeout_cap(timeout),
1521                                        back_to_sleep, LWI_ON_SIGNAL_NOOP, NULL);
1522                 rc = l_wait_event(imp->imp_recovery_waitq,
1523                                   !ptlrpc_import_in_recovery(imp), &lwi);
1524         }
1525
1526         spin_lock(&imp->imp_lock);
1527         if (imp->imp_state != LUSTRE_IMP_FULL)
1528                 goto out;
1529         spin_unlock(&imp->imp_lock);
1530
1531         req = ptlrpc_request_alloc_pack(imp, &RQF_MDS_DISCONNECT,
1532                                         LUSTRE_OBD_VERSION, rq_opc);
1533         if (req) {
1534                 /* We are disconnecting, do not retry a failed DISCONNECT rpc if
1535                  * it fails.  We can get through the above with a down server
1536                  * if the client doesn't know the server is gone yet.
1537                  */
1538                 req->rq_no_resend = 1;
1539
1540                 /* We want client umounts to happen quickly, no matter the
1541                  * server state...
1542                  */
1543                 req->rq_timeout = min_t(int, req->rq_timeout,
1544                                         INITIAL_CONNECT_TIMEOUT);
1545
1546                 IMPORT_SET_STATE(imp, LUSTRE_IMP_CONNECTING);
1547                 req->rq_send_state = LUSTRE_IMP_CONNECTING;
1548                 ptlrpc_request_set_replen(req);
1549                 rc = ptlrpc_queue_wait(req);
1550                 ptlrpc_req_finished(req);
1551         }
1552
1553 set_state:
1554         spin_lock(&imp->imp_lock);
1555 out:
1556         if (noclose)
1557                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
1558         else
1559                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CLOSED);
1560         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
1561         spin_unlock(&imp->imp_lock);
1562
1563         if (rc == -ETIMEDOUT || rc == -ENOTCONN || rc == -ESHUTDOWN)
1564                 rc = 0;
1565
1566         return rc;
1567 }
1568 EXPORT_SYMBOL(ptlrpc_disconnect_import);
1569
1570 /* Adaptive Timeout utils */
1571 extern unsigned int at_min, at_max, at_history;
1572
1573 /*
1574  *Update at_current with the specified value (bounded by at_min and at_max),
1575  * as well as the AT history "bins".
1576  *  - Bin into timeslices using AT_BINS bins.
1577  *  - This gives us a max of the last at_history seconds without the storage,
1578  *    but still smoothing out a return to normalcy from a slow response.
1579  *  - (E.g. remember the maximum latency in each minute of the last 4 minutes.)
1580  */
1581 int at_measured(struct adaptive_timeout *at, unsigned int val)
1582 {
1583         unsigned int old = at->at_current;
1584         time64_t now = ktime_get_real_seconds();
1585         long binlimit = max_t(long, at_history / AT_BINS, 1);
1586
1587         LASSERT(at);
1588         CDEBUG(D_OTHER, "add %u to %p time=%lu v=%u (%u %u %u %u)\n",
1589                val, at, (long)(now - at->at_binstart), at->at_current,
1590                at->at_hist[0], at->at_hist[1], at->at_hist[2], at->at_hist[3]);
1591
1592         if (val == 0)
1593                 /* 0's don't count, because we never want our timeout to
1594                  * drop to 0, and because 0 could mean an error
1595                  */
1596                 return 0;
1597
1598         spin_lock(&at->at_lock);
1599
1600         if (unlikely(at->at_binstart == 0)) {
1601                 /* Special case to remove default from history */
1602                 at->at_current = val;
1603                 at->at_worst_ever = val;
1604                 at->at_worst_time = now;
1605                 at->at_hist[0] = val;
1606                 at->at_binstart = now;
1607         } else if (now - at->at_binstart < binlimit) {
1608                 /* in bin 0 */
1609                 at->at_hist[0] = max(val, at->at_hist[0]);
1610                 at->at_current = max(val, at->at_current);
1611         } else {
1612                 int i, shift;
1613                 unsigned int maxv = val;
1614                 /* move bins over */
1615                 shift = (u32)(now - at->at_binstart) / binlimit;
1616                 LASSERT(shift > 0);
1617                 for (i = AT_BINS - 1; i >= 0; i--) {
1618                         if (i >= shift) {
1619                                 at->at_hist[i] = at->at_hist[i - shift];
1620                                 maxv = max(maxv, at->at_hist[i]);
1621                         } else {
1622                                 at->at_hist[i] = 0;
1623                         }
1624                 }
1625                 at->at_hist[0] = val;
1626                 at->at_current = maxv;
1627                 at->at_binstart += shift * binlimit;
1628         }
1629
1630         if (at->at_current > at->at_worst_ever) {
1631                 at->at_worst_ever = at->at_current;
1632                 at->at_worst_time = now;
1633         }
1634
1635         if (at->at_flags & AT_FLG_NOHIST)
1636                 /* Only keep last reported val; keeping the rest of the history
1637                  * for debugfs only
1638                  */
1639                 at->at_current = val;
1640
1641         if (at_max > 0)
1642                 at->at_current =  min(at->at_current, at_max);
1643         at->at_current =  max(at->at_current, at_min);
1644
1645         if (at->at_current != old)
1646                 CDEBUG(D_OTHER, "AT %p change: old=%u new=%u delta=%d (val=%u) hist %u %u %u %u\n",
1647                        at,
1648                        old, at->at_current, at->at_current - old, val,
1649                        at->at_hist[0], at->at_hist[1], at->at_hist[2],
1650                        at->at_hist[3]);
1651
1652         /* if we changed, report the old value */
1653         old = (at->at_current != old) ? old : 0;
1654
1655         spin_unlock(&at->at_lock);
1656         return old;
1657 }
1658
1659 /* Find the imp_at index for a given portal; assign if space available */
1660 int import_at_get_index(struct obd_import *imp, int portal)
1661 {
1662         struct imp_at *at = &imp->imp_at;
1663         int i;
1664
1665         for (i = 0; i < IMP_AT_MAX_PORTALS; i++) {
1666                 if (at->iat_portal[i] == portal)
1667                         return i;
1668                 if (at->iat_portal[i] == 0)
1669                         /* unused */
1670                         break;
1671         }
1672
1673         /* Not found in list, add it under a lock */
1674         spin_lock(&imp->imp_lock);
1675
1676         /* Check unused under lock */
1677         for (; i < IMP_AT_MAX_PORTALS; i++) {
1678                 if (at->iat_portal[i] == portal)
1679                         goto out;
1680                 if (at->iat_portal[i] == 0)
1681                         /* unused */
1682                         break;
1683         }
1684
1685         /* Not enough portals? */
1686         LASSERT(i < IMP_AT_MAX_PORTALS);
1687
1688         at->iat_portal[i] = portal;
1689 out:
1690         spin_unlock(&imp->imp_lock);
1691         return i;
1692 }