lustre/ldlm/ldlm_lib.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #ifndef EXPORT_SYMTAB
  23 # define EXPORT_SYMTAB
  24 #endif
  25 #define DEBUG_SUBSYSTEM S_LDLM
  26
  27 #ifdef __KERNEL__
  28 # include <linux/module.h>
  29 #else
  30 # include <liblustre.h>
  31 #endif
  32 #include <linux/obd.h>
  33 #include <linux/obd_ost.h> /* for LUSTRE_OSC_NAME */
  34 #include <linux/lustre_mds.h> /* for LUSTRE_MDC_NAME */
  35 #include <linux/lustre_mgmt.h>
  36 #include <linux/lustre_dlm.h>
  37 #include <linux/lustre_net.h>
  38
  39 int client_obd_setup(struct obd_device *obddev, obd_count len, void *buf)
  40 {
  41         struct ptlrpc_connection *conn;
  42         struct lustre_cfg* lcfg = buf;
  43         struct client_obd *cli = &obddev->u.cli;
  44         struct obd_import *imp;
  45         struct obd_uuid server_uuid;
  46         int rq_portal, rp_portal, connect_op;
  47         char *name = obddev->obd_type->typ_name;
  48         char *mgmt_name = NULL;
  49         int rc;
  50         struct obd_device *mgmt_obd;
  51         mgmtcli_register_for_events_t register_f;
  52         ENTRY;
  53
  54         /* In a more perfect world, we would hang a ptlrpc_client off of
  55          * obd_type and just use the values from there. */
  56         if (!strcmp(name, LUSTRE_OSC_NAME)) {
  57                 rq_portal = OST_REQUEST_PORTAL;
  58                 rp_portal = OSC_REPLY_PORTAL;
  59                 connect_op = OST_CONNECT;
  60         } else if (!strcmp(name, LUSTRE_MDC_NAME)) {
  61                 rq_portal = MDS_REQUEST_PORTAL;
  62                 rp_portal = MDC_REPLY_PORTAL;
  63                 connect_op = MDS_CONNECT;
  64         } else if (!strcmp(name, LUSTRE_MGMTCLI_NAME)) {
  65                 rq_portal = MGMT_REQUEST_PORTAL;
  66                 rp_portal = MGMT_REPLY_PORTAL;
  67                 connect_op = MGMT_CONNECT;
  68         } else {
  69                 CERROR("unknown client OBD type \"%s\", can't setup\n",
  70                        name);
  71                 RETURN(-EINVAL);
  72         }
  73
  74         if (lcfg->lcfg_inllen1 < 1) {
  75                 CERROR("requires a TARGET UUID\n");
  76                 RETURN(-EINVAL);
  77         }
  78
  79         if (lcfg->lcfg_inllen1 > 37) {
  80                 CERROR("client UUID must be less than 38 characters\n");
  81                 RETURN(-EINVAL);
  82         }
  83
  84         if (lcfg->lcfg_inllen2 < 1) {
  85                 CERROR("setup requires a SERVER UUID\n");
  86                 RETURN(-EINVAL);
  87         }
  88
  89         if (lcfg->lcfg_inllen2 > 37) {
  90                 CERROR("target UUID must be less than 38 characters\n");
  91                 RETURN(-EINVAL);
  92         }
  93
  94         sema_init(&cli->cl_sem, 1);
  95         cli->cl_conn_count = 0;
  96         memcpy(server_uuid.uuid, lcfg->lcfg_inlbuf2,
  97                min_t(unsigned int, lcfg->lcfg_inllen2, sizeof(server_uuid)));
  98
  99         cli->cl_dirty = 0;
 100         cli->cl_avail_grant = 0;
 101         cli->cl_dirty_max = OSC_MAX_DIRTY_DEFAULT * 1024 * 1024;
 102         INIT_LIST_HEAD(&cli->cl_cache_waiters);
 103         INIT_LIST_HEAD(&cli->cl_loi_ready_list);
 104         INIT_LIST_HEAD(&cli->cl_loi_write_list);
 105         INIT_LIST_HEAD(&cli->cl_loi_read_list);
 106         spin_lock_init(&cli->cl_loi_list_lock);
 107         cli->cl_brw_in_flight = 0;
 108         spin_lock_init(&cli->cl_read_rpc_hist.oh_lock);
 109         spin_lock_init(&cli->cl_write_rpc_hist.oh_lock);
 110         spin_lock_init(&cli->cl_read_page_hist.oh_lock);
 111         spin_lock_init(&cli->cl_write_page_hist.oh_lock);
 112         cli->cl_max_pages_per_rpc = PTLRPC_MAX_BRW_PAGES;
 113         cli->cl_max_rpcs_in_flight = OSC_MAX_RIF_DEFAULT;
 114
 115         rc = ldlm_get_ref();
 116         if (rc) {
 117                 CERROR("ldlm_get_ref failed: %d\n", rc);
 118                 GOTO(err, rc);
 119         }
 120
 121         conn = ptlrpc_uuid_to_connection(&server_uuid);
 122         if (conn == NULL)
 123                 GOTO(err_ldlm, rc = -ENOENT);
 124
 125         ptlrpc_init_client(rq_portal, rp_portal, name,
 126                            &obddev->obd_ldlm_client);
 127
 128         imp = class_new_import();
 129         if (imp == NULL) {
 130                 ptlrpc_put_connection(conn);
 131                 GOTO(err_ldlm, rc = -ENOENT);
 132         }
 133         imp->imp_connection = conn;
 134         imp->imp_client = &obddev->obd_ldlm_client;
 135         imp->imp_obd = obddev;
 136         imp->imp_connect_op = connect_op;
 137         imp->imp_generation = 0;
 138         imp->imp_initial_recov = 1;
 139         INIT_LIST_HEAD(&imp->imp_pinger_chain);
 140         memcpy(imp->imp_target_uuid.uuid, lcfg->lcfg_inlbuf1,
 141               lcfg->lcfg_inllen1);
 142         class_import_put(imp);
 143
 144         cli->cl_import = imp;
 145         cli->cl_max_mds_easize = sizeof(struct lov_mds_md);
 146         cli->cl_max_mds_cookiesize = sizeof(struct llog_cookie);
 147         cli->cl_sandev = to_kdev_t(0);
 148
 149         if (lcfg->lcfg_inllen3 != 0) {
 150                 if (!strcmp(lcfg->lcfg_inlbuf3, "inactive")) {
 151                         CDEBUG(D_HA, "marking %s %s->%s as inactive\n",
 152                                name, obddev->obd_name,
 153                                imp->imp_target_uuid.uuid);
 154                         imp->imp_invalid = 1;
 155
 156                         if (lcfg->lcfg_inllen4 != 0)
 157                                 mgmt_name = lcfg->lcfg_inlbuf4;
 158                 } else {
 159                         mgmt_name = lcfg->lcfg_inlbuf3;
 160                 }
 161         }
 162
 163         if (mgmt_name != NULL) {
 164                 /* Register with management client if we need to. */
 165                 CDEBUG(D_HA, "%s registering with %s for events about %s\n",
 166                        obddev->obd_name, mgmt_name, server_uuid.uuid);
 167
 168                 mgmt_obd = class_name2obd(mgmt_name);
 169                 if (!mgmt_obd) {
 170                         CERROR("can't find mgmtcli %s to register\n",
 171                                mgmt_name);
 172                         GOTO(err_import, rc = -ENOSYS);
 173                 }
 174
 175                 register_f = inter_module_get("mgmtcli_register_for_events");
 176                 if (!register_f) {
 177                         CERROR("can't i_m_g mgmtcli_register_for_events\n");
 178                         GOTO(err_import, rc = -ENOSYS);
 179                 }
 180
 181                 rc = register_f(mgmt_obd, obddev, &imp->imp_target_uuid);
 182                 inter_module_put("mgmtcli_register_for_events");
 183
 184                 if (!rc)
 185                         cli->cl_mgmtcli_obd = mgmt_obd;
 186         }
 187
 188         RETURN(rc);
 189
 190 err_import:
 191         class_destroy_import(imp);
 192 err_ldlm:
 193         ldlm_put_ref(0);
 194 err:
 195         RETURN(rc);
 196
 197 }
 198
 199 int client_obd_cleanup(struct obd_device *obddev, int flags)
 200 {
 201         struct client_obd *cli = &obddev->u.cli;
 202
 203         if (!cli->cl_import)
 204                 RETURN(-EINVAL);
 205         if (cli->cl_mgmtcli_obd) {
 206                 mgmtcli_deregister_for_events_t dereg_f;
 207
 208                 dereg_f = inter_module_get("mgmtcli_deregister_for_events");
 209                 dereg_f(cli->cl_mgmtcli_obd, obddev);
 210                 inter_module_put("mgmtcli_deregister_for_events");
 211         }
 212         class_destroy_import(cli->cl_import);
 213         cli->cl_import = NULL;
 214
 215         ldlm_put_ref(flags & OBD_OPT_FORCE);
 216
 217         RETURN(0);
 218 }
 219
 220 int client_connect_import(struct lustre_handle *dlm_handle,
 221                           struct obd_device *obd,
 222                           struct obd_uuid *cluuid)
 223 {
 224         struct client_obd *cli = &obd->u.cli;
 225         struct obd_import *imp = cli->cl_import;
 226         struct obd_export *exp;
 227         int rc;
 228         ENTRY;
 229
 230         down(&cli->cl_sem);
 231         rc = class_connect(dlm_handle, obd, cluuid);
 232         if (rc)
 233                 GOTO(out_sem, rc);
 234
 235         cli->cl_conn_count++;
 236         if (cli->cl_conn_count > 1)
 237                 GOTO(out_sem, rc);
 238         exp = class_conn2export(dlm_handle);
 239
 240         if (obd->obd_namespace != NULL)
 241                 CERROR("already have namespace!\n");
 242         obd->obd_namespace = ldlm_namespace_new(obd->obd_name,
 243                                                 LDLM_NAMESPACE_CLIENT);
 244         if (obd->obd_namespace == NULL)
 245                 GOTO(out_disco, rc = -ENOMEM);
 246
 247         imp->imp_dlm_handle = *dlm_handle;
 248         rc = ptlrpc_init_import(imp);
 249         if (rc != 0)
 250                 GOTO(out_ldlm, rc);
 251
 252         exp->exp_connection = ptlrpc_connection_addref(imp->imp_connection);
 253         rc = ptlrpc_connect_import(imp, NULL);
 254         if (rc != 0) {
 255                 LASSERT (imp->imp_state == LUSTRE_IMP_DISCON);
 256                 GOTO(out_ldlm, rc);
 257         }
 258
 259         ptlrpc_pinger_add_import(imp);
 260         EXIT;
 261
 262         if (rc) {
 263 out_ldlm:
 264                 ldlm_namespace_free(obd->obd_namespace, 0);
 265                 obd->obd_namespace = NULL;
 266 out_disco:
 267                 cli->cl_conn_count--;
 268                 class_disconnect(exp, 0);
 269         } else {
 270                 class_export_put(exp);
 271         }
 272 out_sem:
 273         up(&cli->cl_sem);
 274         return rc;
 275 }
 276
 277 int client_disconnect_export(struct obd_export *exp, int failover)
 278 {
 279         struct obd_device *obd = class_exp2obd(exp);
 280         struct client_obd *cli = &obd->u.cli;
 281         struct obd_import *imp = cli->cl_import;
 282         int rc = 0, err;
 283         ENTRY;
 284
 285         if (!obd) {
 286                 CERROR("invalid export for disconnect: exp %p cookie "LPX64"\n",
 287                        exp, exp ? exp->exp_handle.h_cookie : -1);
 288                 RETURN(-EINVAL);
 289         }
 290
 291         down(&cli->cl_sem);
 292         if (!cli->cl_conn_count) {
 293                 CERROR("disconnecting disconnected device (%s)\n",
 294                        obd->obd_name);
 295                 GOTO(out_sem, rc = -EINVAL);
 296         }
 297
 298         cli->cl_conn_count--;
 299         if (cli->cl_conn_count)
 300                 GOTO(out_no_disconnect, rc = 0);
 301
 302         /* Some non-replayable imports (MDS's OSCs) are pinged, so just
 303          * delete it regardless.  (It's safe to delete an import that was
 304          * never added.) */
 305         (void)ptlrpc_pinger_del_import(imp);
 306
 307         if (obd->obd_namespace != NULL) {
 308                 /* obd_no_recov == local only */
 309                 ldlm_cli_cancel_unused(obd->obd_namespace, NULL,
 310                                        obd->obd_no_recov, NULL);
 311                 ldlm_namespace_free(obd->obd_namespace, obd->obd_no_recov);
 312                 obd->obd_namespace = NULL;
 313         }
 314
 315         /* Yeah, obd_no_recov also (mainly) means "forced shutdown". */
 316         if (obd->obd_no_recov)
 317                 ptlrpc_invalidate_import(imp, 0);
 318         else
 319                 rc = ptlrpc_disconnect_import(imp);
 320
 321         EXIT;
 322  out_no_disconnect:
 323         err = class_disconnect(exp, 0);
 324         if (!rc && err)
 325                 rc = err;
 326  out_sem:
 327         up(&cli->cl_sem);
 328         RETURN(rc);
 329 }
 330
 331 /* --------------------------------------------------------------------------
 332  * from old lib/target.c
 333  * -------------------------------------------------------------------------- */
 334
 335 int target_handle_reconnect(struct lustre_handle *conn, struct obd_export *exp,
 336                             struct obd_uuid *cluuid, int initial_conn)
 337 {
 338         if (exp->exp_connection && !initial_conn) {
 339                 struct lustre_handle *hdl;
 340                 hdl = &exp->exp_imp_reverse->imp_remote_handle;
 341                 /* Might be a re-connect after a partition. */
 342                 if (!memcmp(&conn->cookie, &hdl->cookie, sizeof conn->cookie)) {
 343                         CERROR("%s reconnecting\n", cluuid->uuid);
 344                         conn->cookie = exp->exp_handle.h_cookie;
 345                         RETURN(EALREADY);
 346                 } else {
 347                         CERROR("%s reconnecting from %s, "
 348                                "handle mismatch (ours "LPX64", theirs "
 349                                LPX64")\n", cluuid->uuid,
 350                                exp->exp_connection->c_remote_uuid.uuid,
 351                                hdl->cookie, conn->cookie);
 352                         memset(conn, 0, sizeof *conn);
 353                         RETURN(-EALREADY);
 354                 }
 355         }
 356
 357         conn->cookie = exp->exp_handle.h_cookie;
 358         CDEBUG(D_INFO, "existing export for UUID '%s' at %p\n",
 359                cluuid->uuid, exp);
 360         CDEBUG(D_IOCTL,"connect: cookie "LPX64"\n", conn->cookie);
 361         RETURN(0);
 362 }
 363
 364 int target_handle_connect(struct ptlrpc_request *req, svc_handler_t handler)
 365 {
 366         struct obd_device *target;
 367         struct obd_export *export = NULL;
 368         struct obd_import *revimp;
 369         struct lustre_handle conn;
 370         struct obd_uuid tgtuuid;
 371         struct obd_uuid cluuid;
 372         struct obd_uuid remote_uuid;
 373         struct list_head *p;
 374         char *str, *tmp;
 375         int rc = 0, abort_recovery;
 376         unsigned long flags;
 377         int initial_conn = 0;
 378         char peer_str[PTL_NALFMT_SIZE];
 379         ENTRY;
 380
 381         OBD_RACE(OBD_FAIL_TGT_CONN_RACE);
 382
 383         LASSERT_REQSWAB (req, 0);
 384         str = lustre_msg_string(req->rq_reqmsg, 0, sizeof(tgtuuid) - 1);
 385         if (str == NULL) {
 386                 CERROR("bad target UUID for connect\n");
 387                 GOTO(out, rc = -EINVAL);
 388         }
 389
 390         obd_str2uuid (&tgtuuid, str);
 391         target = class_uuid2obd(&tgtuuid);
 392         if (!target) {
 393                 target = class_name2obd(str);
 394         }
 395
 396         if (!target || target->obd_stopping || !target->obd_set_up) {
 397                 CERROR("UUID '%s' is not available for connect\n", str);
 398
 399                 GOTO(out, rc = -ENODEV);
 400         }
 401
 402         LASSERT_REQSWAB (req, 1);
 403         str = lustre_msg_string(req->rq_reqmsg, 1, sizeof(cluuid) - 1);
 404         if (str == NULL) {
 405                 CERROR("bad client UUID for connect\n");
 406                 GOTO(out, rc = -EINVAL);
 407         }
 408
 409         obd_str2uuid (&cluuid, str);
 410
 411         /* XXX extract a nettype and format accordingly */
 412         switch (sizeof(ptl_nid_t)) {
 413                 /* NB the casts only avoid compiler warnings */
 414         case 8:
 415                 snprintf(remote_uuid.uuid, sizeof remote_uuid,
 416                          "NET_"LPX64"_UUID", (__u64)req->rq_peer.peer_nid);
 417                 break;
 418         case 4:
 419                 snprintf(remote_uuid.uuid, sizeof remote_uuid,
 420                          "NET_%x_UUID", (__u32)req->rq_peer.peer_nid);
 421                 break;
 422         default:
 423                 LBUG();
 424         }
 425
 426         spin_lock_bh(&target->obd_processing_task_lock);
 427         abort_recovery = target->obd_abort_recovery;
 428         spin_unlock_bh(&target->obd_processing_task_lock);
 429         if (abort_recovery)
 430                 target_abort_recovery(target);
 431
 432         tmp = lustre_msg_buf(req->rq_reqmsg, 2, sizeof conn);
 433         if (tmp == NULL)
 434                 GOTO(out, rc = -EPROTO);
 435
 436         memcpy(&conn, tmp, sizeof conn);
 437
 438         rc = lustre_pack_reply(req, 0, NULL, NULL);
 439         if (rc)
 440                 GOTO(out, rc);
 441
 442         if (lustre_msg_get_op_flags(req->rq_reqmsg) & MSG_CONNECT_INITIAL)
 443                 initial_conn = 1;
 444
 445         /* lctl gets a backstage, all-access pass. */
 446         if (obd_uuid_equals(&cluuid, &target->obd_uuid))
 447                 goto dont_check_exports;
 448
 449         spin_lock(&target->obd_dev_lock);
 450         list_for_each(p, &target->obd_exports) {
 451                 export = list_entry(p, struct obd_export, exp_obd_chain);
 452                 if (obd_uuid_equals(&cluuid, &export->exp_client_uuid)) {
 453                         spin_unlock(&target->obd_dev_lock);
 454                         LASSERT(export->exp_obd == target);
 455
 456                         rc = target_handle_reconnect(&conn, export, &cluuid,
 457                                                      initial_conn);
 458                         break;
 459                 }
 460                 export = NULL;
 461         }
 462         /* If we found an export, we already unlocked. */
 463         if (!export) {
 464                 spin_unlock(&target->obd_dev_lock);
 465         } else if (req->rq_export == NULL &&
 466                    atomic_read(&export->exp_rpc_count) > 0) {
 467                 CWARN("%s: refuse connection from %s/%s to 0x%p/%d\n",
 468                       target->obd_name, cluuid.uuid,
 469                       ptlrpc_peernid2str(&req->rq_peer, peer_str),
 470                       export, atomic_read(&export->exp_refcount));
 471                 GOTO(out, rc = -EBUSY);
 472         } else if (req->rq_export != NULL &&
 473                    atomic_read(&export->exp_rpc_count) > 1) {
 474                 CWARN("%s: refuse reconnection from %s@%s to 0x%p/%d\n",
 475                       target->obd_name, cluuid.uuid,
 476                       ptlrpc_peernid2str(&req->rq_peer, peer_str),
 477                       export, atomic_read(&export->exp_rpc_count));
 478                 GOTO(out, rc = -EBUSY);
 479         }
 480         else if (req->rq_reqmsg->conn_cnt == 1 && !initial_conn) {
 481                 CERROR("%s reconnected with 1 conn_cnt; cookies not random?\n",
 482                        cluuid.uuid);
 483                 GOTO(out, rc = -EALREADY);
 484         }
 485
 486         /* Tell the client if we're in recovery. */
 487         /* If this is the first client, start the recovery timer */
 488         CWARN("%s: connection from %s@%s %s\n", target->obd_name, cluuid.uuid,
 489               ptlrpc_peernid2str(&req->rq_peer, peer_str),
 490               target->obd_recovering ? "(recovering)" : "");
 491         if (target->obd_recovering) {
 492                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_RECOVERING);
 493                 target_start_recovery_timer(target, handler);
 494         }
 495 #if 0
 496         /* Tell the client if we support replayable requests */
 497         if (target->obd_replayable)
 498                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_REPLAYABLE);
 499 #endif
 500         if (export == NULL) {
 501                 if (target->obd_recovering) {
 502                         CERROR("denying connection for new client %s@%s: "
 503                                "%d clients in recovery for %lds\n", cluuid.uuid,
 504                                ptlrpc_peernid2str(&req->rq_peer, peer_str),
 505                                target->obd_recoverable_clients,
 506                                (target->obd_recovery_timer.expires-jiffies)/HZ);
 507                         rc = -EBUSY;
 508                 } else {
 509  dont_check_exports:
 510                         rc = obd_connect(&conn, target, &cluuid);
 511                 }
 512         }
 513         /* Tell the client if we support replayable requests */
 514         if (target->obd_replayable)
 515                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_REPLAYABLE);
 516
 517         /* If all else goes well, this is our RPC return code. */
 518         req->rq_status = 0;
 519
 520         if (rc && rc != EALREADY)
 521                 GOTO(out, rc);
 522
 523         req->rq_repmsg->handle = conn;
 524
 525         /* If the client and the server are the same node, we will already
 526          * have an export that really points to the client's DLM export,
 527          * because we have a shared handles table.
 528          *
 529          * XXX this will go away when shaver stops sending the "connect" handle
 530          * in the real "remote handle" field of the request --phik 24 Apr 2003
 531          */
 532         if (req->rq_export != NULL)
 533                 class_export_put(req->rq_export);
 534
 535         /* ownership of this export ref transfers to the request */
 536         export = req->rq_export = class_conn2export(&conn);
 537         LASSERT(export != NULL);
 538
 539         spin_lock_irqsave(&export->exp_lock, flags);
 540         if (initial_conn) {
 541                 req->rq_repmsg->conn_cnt = export->exp_conn_cnt + 1;
 542         } else if (export->exp_conn_cnt >= req->rq_reqmsg->conn_cnt) {
 543                 CERROR("%s@%s: already connected at a higher conn_cnt: %d > %d\n",
 544                        cluuid.uuid, ptlrpc_peernid2str(&req->rq_peer, peer_str),
 545                        export->exp_conn_cnt,
 546                        req->rq_reqmsg->conn_cnt);
 547                 spin_unlock_irqrestore(&export->exp_lock, flags);
 548                 GOTO(out, rc = -EALREADY);
 549         }
 550         export->exp_conn_cnt = req->rq_reqmsg->conn_cnt;
 551         spin_unlock_irqrestore(&export->exp_lock, flags);
 552
 553         /* request from liblustre? */
 554         if (lustre_msg_get_op_flags(req->rq_reqmsg) & MSG_CONNECT_LIBCLIENT)
 555                 export->exp_libclient = 1;
 556
 557         if (export->exp_connection != NULL)
 558                 ptlrpc_put_connection(export->exp_connection);
 559         export->exp_connection = ptlrpc_get_connection(&req->rq_peer,
 560                                                        &remote_uuid);
 561
 562         if (rc == EALREADY) {
 563                 /* We indicate the reconnection in a flag, not an error code. */
 564                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_RECONNECT);
 565                 GOTO(out, rc = 0);
 566         }
 567
 568         if (target->obd_recovering) {
 569                 target->obd_connected_clients++;
 570         }
 571
 572         memcpy(&conn, lustre_msg_buf(req->rq_reqmsg, 2, sizeof conn),
 573                sizeof conn);
 574
 575         if (export->exp_imp_reverse != NULL)
 576                 class_destroy_import(export->exp_imp_reverse);
 577         revimp = export->exp_imp_reverse = class_new_import();
 578         revimp->imp_connection = ptlrpc_connection_addref(export->exp_connection);
 579         revimp->imp_client = &export->exp_obd->obd_ldlm_client;
 580         revimp->imp_remote_handle = conn;
 581         revimp->imp_obd = target;
 582         revimp->imp_dlm_fake = 1;
 583         revimp->imp_state = LUSTRE_IMP_FULL;
 584         class_import_put(revimp);
 585 out:
 586         if (rc)
 587                 req->rq_status = rc;
 588         RETURN(rc);
 589 }
 590
 591 int target_handle_disconnect(struct ptlrpc_request *req)
 592 {
 593         struct obd_export *exp;
 594         int rc;
 595         ENTRY;
 596
 597         rc = lustre_pack_reply(req, 0, NULL, NULL);
 598         if (rc)
 599                 RETURN(rc);
 600
 601         /* keep the rq_export around so we can send the reply */
 602         exp = class_export_get(req->rq_export);
 603         req->rq_status = obd_disconnect(exp, 0);
 604         RETURN(0);
 605 }
 606
 607 void target_destroy_export(struct obd_export *exp)
 608 {
 609         /* exports created from last_rcvd data, and "fake"
 610            exports created by lctl don't have an import */
 611         if (exp->exp_imp_reverse != NULL)
 612                 class_destroy_import(exp->exp_imp_reverse);
 613
 614         /* We cancel locks at disconnect time, but this will catch any locks
 615          * granted in a race with recovery-induced disconnect. */
 616         if (exp->exp_obd->obd_namespace != NULL)
 617                 ldlm_cancel_locks_for_export(exp);
 618 }
 619
 620 /*
 621  * Recovery functions
 622  */
 623
 624 static void abort_delayed_replies(struct obd_device *obd)
 625 {
 626         struct ptlrpc_request *req;
 627         struct list_head *tmp, *n;
 628         list_for_each_safe(tmp, n, &obd->obd_delayed_reply_queue) {
 629                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 630                 DEBUG_REQ(D_ERROR, req, "aborted:");
 631                 req->rq_status = -ENOTCONN;
 632                 req->rq_type = PTL_RPC_MSG_ERR;
 633                 ptlrpc_reply(req);
 634                 class_export_put(req->rq_export);
 635                 list_del(&req->rq_list);
 636                 OBD_FREE(req->rq_reqmsg, req->rq_reqlen);
 637                 OBD_FREE(req, sizeof *req);
 638         }
 639 }
 640
 641 static void abort_recovery_queue(struct obd_device *obd)
 642 {
 643         struct ptlrpc_request *req;
 644         struct list_head *tmp, *n;
 645         int rc;
 646
 647         list_for_each_safe(tmp, n, &obd->obd_recovery_queue) {
 648                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 649                 DEBUG_REQ(D_ERROR, req, "aborted:");
 650                 req->rq_status = -ENOTCONN;
 651                 req->rq_type = PTL_RPC_MSG_ERR;
 652                 rc = lustre_pack_reply(req, 0, NULL, NULL);
 653                 if (rc == 0) {
 654                         ptlrpc_reply(req);
 655                 } else {
 656                         DEBUG_REQ(D_ERROR, req,
 657                                   "packing failed for abort-reply; skipping");
 658                 }
 659                 list_del(&req->rq_list);
 660                 class_export_put(req->rq_export);
 661                 OBD_FREE(req->rq_reqmsg, req->rq_reqlen);
 662                 OBD_FREE(req, sizeof *req);
 663         }
 664 }
 665
 666 void target_abort_recovery(void *data)
 667 {
 668         struct obd_device *obd = data;
 669         int rc;
 670
 671         CERROR("disconnecting clients and aborting recovery\n");
 672         spin_lock_bh(&obd->obd_processing_task_lock);
 673         if (!obd->obd_recovering) {
 674                 spin_unlock_bh(&obd->obd_processing_task_lock);
 675                 EXIT;
 676                 return;
 677         }
 678
 679         obd->obd_recovering = obd->obd_abort_recovery = 0;
 680
 681         wake_up(&obd->obd_next_transno_waitq);
 682         target_cancel_recovery_timer(obd);
 683         spin_unlock_bh(&obd->obd_processing_task_lock);
 684
 685         class_disconnect_exports(obd, 0);
 686
 687         /* when recovery was aborted, cleanup orphans on mds and ost */
 688         if (OBT(obd) && OBP(obd, postrecov)) {
 689                 rc = OBP(obd, postrecov)(obd);
 690                 if (rc >= 0)
 691                         CWARN("Cleanup %d orphans after recovery was aborted\n", rc);
 692                 else
 693                         CERROR("postrecov failed %d\n", rc);
 694         }
 695
 696         abort_delayed_replies(obd);
 697         abort_recovery_queue(obd);
 698         ptlrpc_run_recovery_over_upcall(obd);
 699 }
 700
 701 static void target_recovery_expired(unsigned long castmeharder)
 702 {
 703         struct obd_device *obd = (struct obd_device *)castmeharder;
 704         CERROR("recovery timed out, aborting\n");
 705         spin_lock_bh(&obd->obd_processing_task_lock);
 706         obd->obd_abort_recovery = 1;
 707         wake_up(&obd->obd_next_transno_waitq);
 708         spin_unlock_bh(&obd->obd_processing_task_lock);
 709 }
 710
 711
 712 /* obd_processing_task_lock should be held */
 713 void target_cancel_recovery_timer(struct obd_device *obd)
 714 {
 715         CDEBUG(D_HA, "%s: cancel recovery timer\n", obd->obd_name);
 716         del_timer(&obd->obd_recovery_timer);
 717 }
 718
 719 static void reset_recovery_timer(struct obd_device *obd)
 720 {
 721         spin_lock_bh(&obd->obd_processing_task_lock);
 722         if (!obd->obd_recovering) {
 723                 spin_unlock_bh(&obd->obd_processing_task_lock);
 724                 return;
 725         }
 726         CDEBUG(D_HA, "timer will expire in %u seconds\n",
 727                OBD_RECOVERY_TIMEOUT / HZ);
 728         mod_timer(&obd->obd_recovery_timer, jiffies + OBD_RECOVERY_TIMEOUT);
 729         spin_unlock_bh(&obd->obd_processing_task_lock);
 730 }
 731
 732
 733 /* Only start it the first time called */
 734 void target_start_recovery_timer(struct obd_device *obd, svc_handler_t handler)
 735 {
 736         spin_lock_bh(&obd->obd_processing_task_lock);
 737         if (obd->obd_recovery_handler) {
 738                 spin_unlock_bh(&obd->obd_processing_task_lock);
 739                 return;
 740         }
 741         CWARN("%s: starting recovery timer (%us)\n", obd->obd_name,
 742                OBD_RECOVERY_TIMEOUT / HZ);
 743         obd->obd_recovery_handler = handler;
 744         obd->obd_recovery_timer.function = target_recovery_expired;
 745         obd->obd_recovery_timer.data = (unsigned long)obd;
 746         spin_unlock_bh(&obd->obd_processing_task_lock);
 747
 748         reset_recovery_timer(obd);
 749 }
 750
 751 static int check_for_next_transno(struct obd_device *obd)
 752 {
 753         struct ptlrpc_request *req;
 754         int wake_up = 0, connected, completed, queue_len, max;
 755         __u64 next_transno, req_transno;
 756
 757         spin_lock_bh(&obd->obd_processing_task_lock);
 758         req = list_entry(obd->obd_recovery_queue.next,
 759                          struct ptlrpc_request, rq_list);
 760         max = obd->obd_max_recoverable_clients;
 761         req_transno = req->rq_reqmsg->transno;
 762         connected = obd->obd_connected_clients;
 763         completed = max - obd->obd_recoverable_clients;
 764         queue_len = obd->obd_requests_queued_for_recovery;
 765         next_transno = obd->obd_next_recovery_transno;
 766
 767         CDEBUG(D_HA,"max: %d, connected: %d, completed: %d, queue_len: %d, "
 768                "req_transno: "LPU64", next_transno: "LPU64"\n",
 769                max, connected, completed, queue_len, req_transno, next_transno);
 770         if (obd->obd_abort_recovery) {
 771                 CDEBUG(D_HA, "waking for aborted recovery\n");
 772                 wake_up = 1;
 773         } else if (!obd->obd_recovering) {
 774                 CDEBUG(D_HA, "waking for completed recovery (?)\n");
 775                 wake_up = 1;
 776         } else if (req_transno == next_transno) {
 777                 CDEBUG(D_HA, "waking for next ("LPD64")\n", next_transno);
 778                 wake_up = 1;
 779         } else if (queue_len + completed == max) {
 780                 CDEBUG(D_ERROR,
 781                        "waking for skipped transno (skip: "LPD64
 782                        ", ql: %d, comp: %d, conn: %d, next: "LPD64")\n",
 783                        next_transno, queue_len, completed, max, req_transno);
 784                 obd->obd_next_recovery_transno = req_transno;
 785                 wake_up = 1;
 786         }
 787         spin_unlock_bh(&obd->obd_processing_task_lock);
 788         LASSERT(req->rq_reqmsg->transno >= next_transno);
 789         return wake_up;
 790 }
 791
 792 static void process_recovery_queue(struct obd_device *obd)
 793 {
 794         struct ptlrpc_request *req;
 795         int abort_recovery = 0;
 796         struct l_wait_info lwi = { 0 };
 797         ENTRY;
 798
 799         for (;;) {
 800                 spin_lock_bh(&obd->obd_processing_task_lock);
 801                 LASSERT(obd->obd_processing_task == current->pid);
 802                 req = list_entry(obd->obd_recovery_queue.next,
 803                                  struct ptlrpc_request, rq_list);
 804
 805                 if (req->rq_reqmsg->transno != obd->obd_next_recovery_transno) {
 806                         spin_unlock_bh(&obd->obd_processing_task_lock);
 807                         CDEBUG(D_HA, "Waiting for transno "LPD64" (1st is "
 808                                LPD64")\n",
 809                                obd->obd_next_recovery_transno,
 810                                req->rq_reqmsg->transno);
 811                         l_wait_event(obd->obd_next_transno_waitq,
 812                                      check_for_next_transno(obd), &lwi);
 813                         spin_lock_bh(&obd->obd_processing_task_lock);
 814                         abort_recovery = obd->obd_abort_recovery;
 815                         spin_unlock_bh(&obd->obd_processing_task_lock);
 816                         if (abort_recovery) {
 817                                 target_abort_recovery(obd);
 818                                 return;
 819                         }
 820                         continue;
 821                 }
 822                 list_del_init(&req->rq_list);
 823                 obd->obd_requests_queued_for_recovery--;
 824                 spin_unlock_bh(&obd->obd_processing_task_lock);
 825
 826                 DEBUG_REQ(D_HA, req, "processing: ");
 827                 (void)obd->obd_recovery_handler(req);
 828                 obd->obd_replayed_requests++;
 829                 reset_recovery_timer(obd);
 830                 /* bug 1580: decide how to properly sync() in recovery */
 831                 //mds_fsync_super(mds->mds_sb);
 832                 class_export_put(req->rq_export);
 833                 OBD_FREE(req->rq_reqmsg, req->rq_reqlen);
 834                 OBD_FREE(req, sizeof *req);
 835                 spin_lock_bh(&obd->obd_processing_task_lock);
 836                 obd->obd_next_recovery_transno++;
 837                 if (list_empty(&obd->obd_recovery_queue)) {
 838                         obd->obd_processing_task = 0;
 839                         spin_unlock_bh(&obd->obd_processing_task_lock);
 840                         break;
 841                 }
 842                 spin_unlock_bh(&obd->obd_processing_task_lock);
 843         }
 844         EXIT;
 845 }
 846
 847 int target_queue_recovery_request(struct ptlrpc_request *req,
 848                                   struct obd_device *obd)
 849 {
 850         struct list_head *tmp;
 851         int inserted = 0;
 852         __u64 transno = req->rq_reqmsg->transno;
 853         struct ptlrpc_request *saved_req;
 854         struct lustre_msg *reqmsg;
 855
 856         /* CAVEAT EMPTOR: The incoming request message has been swabbed
 857          * (i.e. buflens etc are in my own byte order), but type-dependent
 858          * buffers (eg mds_body, ost_body etc) have NOT been swabbed. */
 859
 860         if (!transno) {
 861                 INIT_LIST_HEAD(&req->rq_list);
 862                 DEBUG_REQ(D_HA, req, "not queueing");
 863                 return 1;
 864         }
 865
 866         /* XXX If I were a real man, these LBUGs would be sane cleanups. */
 867         /* XXX just like the request-dup code in queue_final_reply */
 868         OBD_ALLOC(saved_req, sizeof *saved_req);
 869         if (!saved_req)
 870                 LBUG();
 871         OBD_ALLOC(reqmsg, req->rq_reqlen);
 872         if (!reqmsg)
 873                 LBUG();
 874
 875         spin_lock_bh(&obd->obd_processing_task_lock);
 876
 877         /* If we're processing the queue, we want don't want to queue this
 878          * message.
 879          *
 880          * Also, if this request has a transno less than the one we're waiting
 881          * for, we should process it now.  It could (and currently always will)
 882          * be an open request for a descriptor that was opened some time ago.
 883          *
 884          * Also, a resent, replayed request that has already been
 885          * handled will pass through here and be processed immediately.
 886          */
 887         if (obd->obd_processing_task == current->pid ||
 888             transno < obd->obd_next_recovery_transno) {
 889                 /* Processing the queue right now, don't re-add. */
 890                 LASSERT(list_empty(&req->rq_list));
 891                 spin_unlock_bh(&obd->obd_processing_task_lock);
 892                 OBD_FREE(reqmsg, req->rq_reqlen);
 893                 OBD_FREE(saved_req, sizeof *saved_req);
 894                 return 1;
 895         }
 896
 897         /* A resent, replayed request that is still on the queue; just drop it.
 898            The queued request will handle this. */
 899         if ((lustre_msg_get_flags(req->rq_reqmsg) & (MSG_RESENT | MSG_REPLAY)) ==
 900             (MSG_RESENT | MSG_REPLAY)) {
 901                 DEBUG_REQ(D_ERROR, req, "dropping resent queued req");
 902                 spin_unlock_bh(&obd->obd_processing_task_lock);
 903                 OBD_FREE(reqmsg, req->rq_reqlen);
 904                 OBD_FREE(saved_req, sizeof *saved_req);
 905                 return 0;
 906         }
 907
 908         memcpy(saved_req, req, sizeof *req);
 909         memcpy(reqmsg, req->rq_reqmsg, req->rq_reqlen);
 910         req = saved_req;
 911         req->rq_reqmsg = reqmsg;
 912         class_export_get(req->rq_export);
 913         INIT_LIST_HEAD(&req->rq_list);
 914
 915         /* XXX O(n^2) */
 916         list_for_each(tmp, &obd->obd_recovery_queue) {
 917                 struct ptlrpc_request *reqiter =
 918                         list_entry(tmp, struct ptlrpc_request, rq_list);
 919
 920                 if (reqiter->rq_reqmsg->transno > transno) {
 921                         list_add_tail(&req->rq_list, &reqiter->rq_list);
 922                         inserted = 1;
 923                         break;
 924                 }
 925         }
 926
 927         if (!inserted) {
 928                 list_add_tail(&req->rq_list, &obd->obd_recovery_queue);
 929         }
 930
 931         obd->obd_requests_queued_for_recovery++;
 932
 933         if (obd->obd_processing_task != 0) {
 934                 /* Someone else is processing this queue, we'll leave it to
 935                  * them.
 936                  */
 937                 wake_up(&obd->obd_next_transno_waitq);
 938                 spin_unlock_bh(&obd->obd_processing_task_lock);
 939                 return 0;
 940         }
 941
 942         /* Nobody is processing, and we know there's (at least) one to process
 943          * now, so we'll do the honours.
 944          */
 945         obd->obd_processing_task = current->pid;
 946         spin_unlock_bh(&obd->obd_processing_task_lock);
 947
 948         process_recovery_queue(obd);
 949         return 0;
 950 }
 951
 952 struct obd_device * target_req2obd(struct ptlrpc_request *req)
 953 {
 954         return req->rq_export->exp_obd;
 955 }
 956
 957 int target_queue_final_reply(struct ptlrpc_request *req, int rc)
 958 {
 959         struct obd_device *obd = target_req2obd(req);
 960         struct ptlrpc_request *saved_req;
 961         struct lustre_msg *reqmsg;
 962         int recovery_done = 0;
 963         int rc2;
 964
 965         LASSERT ((rc == 0) == (req->rq_reply_state != NULL));
 966
 967         if (rc) {
 968                 /* Just like ptlrpc_error, but without the sending. */
 969                 rc = lustre_pack_reply(req, 0, NULL, NULL);
 970                 LASSERT(rc == 0); /* XXX handle this */
 971                 req->rq_type = PTL_RPC_MSG_ERR;
 972         }
 973
 974         LASSERT (!req->rq_reply_state->rs_difficult);
 975         LASSERT(list_empty(&req->rq_list));
 976         /* XXX a bit like the request-dup code in queue_recovery_request */
 977         OBD_ALLOC(saved_req, sizeof *saved_req);
 978         if (!saved_req)
 979                 LBUG();
 980         OBD_ALLOC(reqmsg, req->rq_reqlen);
 981         if (!reqmsg)
 982                 LBUG();
 983         memcpy(saved_req, req, sizeof *saved_req);
 984         memcpy(reqmsg, req->rq_reqmsg, req->rq_reqlen);
 985         /* the copied req takes over the reply state */
 986         req->rq_reply_state = NULL;
 987         req = saved_req;
 988         req->rq_reqmsg = reqmsg;
 989         class_export_get(req->rq_export);
 990         list_add(&req->rq_list, &obd->obd_delayed_reply_queue);
 991
 992         spin_lock_bh(&obd->obd_processing_task_lock);
 993         --obd->obd_recoverable_clients;
 994         recovery_done = (obd->obd_recoverable_clients == 0);
 995         spin_unlock_bh(&obd->obd_processing_task_lock);
 996
 997         if (recovery_done) {
 998                 struct list_head *tmp, *n;
 999                 ldlm_reprocess_all_ns(req->rq_export->exp_obd->obd_namespace);
1000                 CWARN("%s: all clients recovered, sending delayed replies\n",
1001                        obd->obd_name);
1002                 spin_lock_bh(&obd->obd_processing_task_lock);
1003                 obd->obd_recovering = 0;
1004                 target_cancel_recovery_timer(obd);
1005                 spin_unlock_bh(&obd->obd_processing_task_lock);
1006
1007                 /* when recovery finished, cleanup orphans on mds and ost */
1008                 if (OBT(obd) && OBP(obd, postrecov)) {
1009                         rc2 = OBP(obd, postrecov)(obd);
1010                         if (rc2 >= 0)
1011                                 CWARN("%s: all clients recovered, %d MDS "
1012                                       "orphans deleted\n", obd->obd_name, rc2);
1013                         else
1014                                 CERROR("postrecov failed %d\n", rc2);
1015                 }
1016
1017                 list_for_each_safe(tmp, n, &obd->obd_delayed_reply_queue) {
1018                         req = list_entry(tmp, struct ptlrpc_request, rq_list);
1019                         DEBUG_REQ(D_ERROR, req, "delayed:");
1020                         ptlrpc_reply(req);
1021                         class_export_put(req->rq_export);
1022                         list_del(&req->rq_list);
1023                         OBD_FREE(req->rq_reqmsg, req->rq_reqlen);
1024                         OBD_FREE(req, sizeof *req);
1025                 }
1026                 ptlrpc_run_recovery_over_upcall(obd);
1027         } else {
1028                 CWARN("%s: %d recoverable clients remain\n",
1029                        obd->obd_name, obd->obd_recoverable_clients);
1030                 wake_up(&obd->obd_next_transno_waitq);
1031         }
1032
1033         return 1;
1034 }
1035
1036 int
1037 target_send_reply_msg (struct ptlrpc_request *req, int rc, int fail_id)
1038 {
1039         if (OBD_FAIL_CHECK(fail_id | OBD_FAIL_ONCE)) {
1040                 obd_fail_loc |= OBD_FAIL_ONCE | OBD_FAILED;
1041                 DEBUG_REQ(D_ERROR, req, "dropping reply");
1042                 /* NB this does _not_ send with ACK disabled, to simulate
1043                  * sending OK, but timing out for the ACK */
1044                 if (req->rq_reply_state != NULL) {
1045                         if (!req->rq_reply_state->rs_difficult) {
1046                                 lustre_free_reply_state (req->rq_reply_state);
1047                                 req->rq_reply_state = NULL;
1048                         } else {
1049                                 struct ptlrpc_service *svc =
1050                                         req->rq_rqbd->rqbd_srv_ni->sni_service;
1051                                 atomic_inc(&svc->srv_outstanding_replies);
1052                         }
1053                 }
1054                 return (-ECOMM);
1055         }
1056
1057         if (rc) {
1058                 DEBUG_REQ(D_ERROR, req, "processing error (%d)", rc);
1059                 if (req->rq_reply_state == NULL) {
1060                         rc = lustre_pack_reply (req, 0, NULL, NULL);
1061                         if (rc != 0) {
1062                                 CERROR ("can't allocate reply\n");
1063                                 return (rc);
1064                         }
1065                 }
1066                 req->rq_type = PTL_RPC_MSG_ERR;
1067         } else {
1068                 DEBUG_REQ(D_NET, req, "sending reply");
1069         }
1070
1071         return (ptlrpc_send_reply(req, 1));
1072 }
1073
1074 void
1075 target_send_reply(struct ptlrpc_request *req, int rc, int fail_id)
1076 {
1077         int                        netrc;
1078         unsigned long              flags;
1079         struct ptlrpc_reply_state *rs;
1080         struct obd_device         *obd;
1081         struct obd_export         *exp;
1082         struct ptlrpc_srv_ni      *sni;
1083         struct ptlrpc_service     *svc;
1084
1085         sni = req->rq_rqbd->rqbd_srv_ni;
1086         svc = sni->sni_service;
1087
1088         rs = req->rq_reply_state;
1089         if (rs == NULL || !rs->rs_difficult) {
1090                 /* The easy case; no notifiers and reply_out_callback()
1091                  * cleans up (i.e. we can't look inside rs after a
1092                  * successful send) */
1093                 netrc = target_send_reply_msg (req, rc, fail_id);
1094
1095                 LASSERT (netrc == 0 || req->rq_reply_state == NULL);
1096                 return;
1097         }
1098
1099         /* must be an export if locks saved */
1100         LASSERT (req->rq_export != NULL);
1101         /* req/reply consistent */
1102         LASSERT (rs->rs_srv_ni == sni);
1103
1104         /* "fresh" reply */
1105         LASSERT (!rs->rs_scheduled);
1106         LASSERT (!rs->rs_scheduled_ever);
1107         LASSERT (!rs->rs_handled);
1108         LASSERT (!rs->rs_on_net);
1109         LASSERT (rs->rs_export == NULL);
1110         LASSERT (list_empty(&rs->rs_obd_list));
1111         LASSERT (list_empty(&rs->rs_exp_list));
1112
1113         exp = class_export_get (req->rq_export);
1114         obd = exp->exp_obd;
1115
1116         /* disable reply scheduling onto srv_reply_queue while I'm setting up */
1117         rs->rs_scheduled = 1;
1118         rs->rs_on_net    = 1;
1119         rs->rs_xid       = req->rq_xid;
1120         rs->rs_transno   = req->rq_transno;
1121         rs->rs_export    = exp;
1122
1123         spin_lock_irqsave (&obd->obd_uncommitted_replies_lock, flags);
1124
1125         if (rs->rs_transno > obd->obd_last_committed) {
1126                 /* not committed already */
1127                 list_add_tail (&rs->rs_obd_list,
1128                                &obd->obd_uncommitted_replies);
1129         }
1130
1131         spin_unlock (&obd->obd_uncommitted_replies_lock);
1132         spin_lock (&exp->exp_lock);
1133
1134         list_add_tail (&rs->rs_exp_list, &exp->exp_outstanding_replies);
1135
1136         spin_unlock_irqrestore (&exp->exp_lock, flags);
1137
1138         netrc = target_send_reply_msg (req, rc, fail_id);
1139
1140         spin_lock_irqsave (&svc->srv_lock, flags);
1141
1142         svc->srv_n_difficult_replies++;
1143
1144         if (netrc != 0) /* error sending: reply is off the net */
1145                 rs->rs_on_net = 0;
1146
1147         if (!rs->rs_on_net ||                   /* some notifier */
1148             list_empty(&rs->rs_exp_list) ||     /* completed already */
1149             list_empty(&rs->rs_obd_list)) {
1150                 list_add_tail (&rs->rs_list, &svc->srv_reply_queue);
1151                 wake_up (&svc->srv_waitq);
1152         } else {
1153                 list_add (&rs->rs_list, &sni->sni_active_replies);
1154                 rs->rs_scheduled = 0;           /* allow notifier to schedule */
1155         }
1156
1157         spin_unlock_irqrestore (&svc->srv_lock, flags);
1158 }
1159
1160 int target_handle_ping(struct ptlrpc_request *req)
1161 {
1162         return lustre_pack_reply(req, 0, NULL, NULL);
1163 }