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LU-12072 lov: remove KEY_CACHE_SET to simplify the code
[fs/lustre-release.git] / lustre / ldlm / ldlm_lib.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) 2010, 2017, 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
33 /**
34  * This file deals with various client/target related logic including recovery.
35  *
36  * TODO: This code more logically belongs in the ptlrpc module than in ldlm and
37  * should be moved.
38  */
39
40 #define DEBUG_SUBSYSTEM S_LDLM
41
42 #include <cl_object.h>
43 #include <linux/jiffies.h>
44 #include <linux/kthread.h>
45 #include <libcfs/libcfs.h>
46 #include <obd.h>
47 #include <obd_class.h>
48 #include <lustre_dlm.h>
49 #include <lustre_net.h>
50 #include <lustre_sec.h>
51 #include "ldlm_internal.h"
52
53 /* @priority: If non-zero, move the selected connection to the list head.
54  * @create: If zero, only search in existing connections.
55  */
56 static int import_set_conn(struct obd_import *imp, struct obd_uuid *uuid,
57                            int priority, int create)
58 {
59         struct ptlrpc_connection *ptlrpc_conn;
60         struct obd_import_conn *imp_conn = NULL, *item;
61         lnet_nid_t nid4refnet = LNET_NID_ANY;
62         int rc = 0;
63         ENTRY;
64
65         if (!create && !priority) {
66                 CDEBUG(D_HA, "Nothing to do\n");
67                 RETURN(-EINVAL);
68         }
69
70         if (imp->imp_connection &&
71             imp->imp_connection->c_remote_uuid.uuid[0] == 0)
72                 /* nid4refnet is used to restrict network connections */
73                 nid4refnet = imp->imp_connection->c_self;
74         ptlrpc_conn = ptlrpc_uuid_to_connection(uuid, nid4refnet);
75         if (!ptlrpc_conn) {
76                 CDEBUG(D_HA, "can't find connection %s\n", uuid->uuid);
77                 RETURN(-ENOENT);
78         }
79
80         if (create) {
81                 OBD_ALLOC(imp_conn, sizeof(*imp_conn));
82                 if (!imp_conn)
83                         GOTO(out_put, rc = -ENOMEM);
84         }
85
86         spin_lock(&imp->imp_lock);
87         list_for_each_entry(item, &imp->imp_conn_list, oic_item) {
88                 if (obd_uuid_equals(uuid, &item->oic_uuid)) {
89                         if (priority) {
90                                 list_del(&item->oic_item);
91                                 list_add(&item->oic_item,
92                                          &imp->imp_conn_list);
93                                 item->oic_last_attempt = 0;
94                         }
95                         CDEBUG(D_HA, "imp %p@%s: found existing conn %s%s\n",
96                                imp, imp->imp_obd->obd_name, uuid->uuid,
97                                (priority ? ", moved to head" : ""));
98                         spin_unlock(&imp->imp_lock);
99                         GOTO(out_free, rc = 0);
100                 }
101         }
102         /* No existing import connection found for \a uuid. */
103         if (create) {
104                 imp_conn->oic_conn = ptlrpc_conn;
105                 imp_conn->oic_uuid = *uuid;
106                 imp_conn->oic_last_attempt = 0;
107                 if (priority)
108                         list_add(&imp_conn->oic_item, &imp->imp_conn_list);
109                 else
110                         list_add_tail(&imp_conn->oic_item,
111                                       &imp->imp_conn_list);
112                 CDEBUG(D_HA, "imp %p@%s: add connection %s at %s\n",
113                        imp, imp->imp_obd->obd_name, uuid->uuid,
114                        (priority ? "head" : "tail"));
115         } else {
116                 spin_unlock(&imp->imp_lock);
117                 GOTO(out_free, rc = -ENOENT);
118         }
119
120         spin_unlock(&imp->imp_lock);
121         RETURN(0);
122 out_free:
123         if (imp_conn)
124                 OBD_FREE(imp_conn, sizeof(*imp_conn));
125 out_put:
126         ptlrpc_connection_put(ptlrpc_conn);
127         RETURN(rc);
128 }
129
130 int import_set_conn_priority(struct obd_import *imp, struct obd_uuid *uuid)
131 {
132         return import_set_conn(imp, uuid, 1, 0);
133 }
134
135 int client_import_add_conn(struct obd_import *imp, struct obd_uuid *uuid,
136                            int priority)
137 {
138         return import_set_conn(imp, uuid, priority, 1);
139 }
140 EXPORT_SYMBOL(client_import_add_conn);
141
142 int client_import_del_conn(struct obd_import *imp, struct obd_uuid *uuid)
143 {
144         struct obd_import_conn *imp_conn;
145         struct obd_export *dlmexp;
146         int rc = -ENOENT;
147         ENTRY;
148
149         spin_lock(&imp->imp_lock);
150         if (list_empty(&imp->imp_conn_list)) {
151                 LASSERT(!imp->imp_connection);
152                 GOTO(out, rc);
153         }
154
155         list_for_each_entry(imp_conn, &imp->imp_conn_list, oic_item) {
156                 if (!obd_uuid_equals(uuid, &imp_conn->oic_uuid))
157                         continue;
158                 LASSERT(imp_conn->oic_conn);
159
160                 if (imp_conn == imp->imp_conn_current) {
161                         LASSERT(imp_conn->oic_conn == imp->imp_connection);
162
163                         if (imp->imp_state != LUSTRE_IMP_CLOSED &&
164                             imp->imp_state != LUSTRE_IMP_DISCON) {
165                                 CERROR("can't remove current connection\n");
166                                 GOTO(out, rc = -EBUSY);
167                         }
168
169                         ptlrpc_connection_put(imp->imp_connection);
170                         imp->imp_connection = NULL;
171
172                         dlmexp = class_conn2export(&imp->imp_dlm_handle);
173                         if (dlmexp && dlmexp->exp_connection) {
174                                 LASSERT(dlmexp->exp_connection ==
175                                         imp_conn->oic_conn);
176                                 ptlrpc_connection_put(dlmexp->exp_connection);
177                                 dlmexp->exp_connection = NULL;
178                         }
179
180                         if (dlmexp != NULL)
181                                 class_export_put(dlmexp);
182                 }
183
184                 list_del(&imp_conn->oic_item);
185                 ptlrpc_connection_put(imp_conn->oic_conn);
186                 OBD_FREE(imp_conn, sizeof(*imp_conn));
187                 CDEBUG(D_HA, "imp %p@%s: remove connection %s\n",
188                        imp, imp->imp_obd->obd_name, uuid->uuid);
189                 rc = 0;
190                 break;
191         }
192 out:
193         spin_unlock(&imp->imp_lock);
194         if (rc == -ENOENT)
195                 CERROR("connection %s not found\n", uuid->uuid);
196         RETURN(rc);
197 }
198 EXPORT_SYMBOL(client_import_del_conn);
199
200 /**
201  * Find conn UUID by peer NID. \a peer is a server NID. This function is used
202  * to find a conn uuid of \a imp which can reach \a peer.
203  */
204 int client_import_find_conn(struct obd_import *imp, lnet_nid_t peer,
205                             struct obd_uuid *uuid)
206 {
207         struct obd_import_conn *conn;
208         int rc = -ENOENT;
209         ENTRY;
210
211         spin_lock(&imp->imp_lock);
212         list_for_each_entry(conn, &imp->imp_conn_list, oic_item) {
213                 /* Check if conn UUID does have this peer NID. */
214                 if (class_check_uuid(&conn->oic_uuid, peer)) {
215                         *uuid = conn->oic_uuid;
216                         rc = 0;
217                         break;
218                 }
219         }
220         spin_unlock(&imp->imp_lock);
221         RETURN(rc);
222 }
223 EXPORT_SYMBOL(client_import_find_conn);
224
225 void client_destroy_import(struct obd_import *imp)
226 {
227         /* Drop security policy instance after all RPCs have finished/aborted
228          * to let all busy contexts be released. */
229         class_import_get(imp);
230         class_destroy_import(imp);
231         sptlrpc_import_sec_put(imp);
232         class_import_put(imp);
233 }
234 EXPORT_SYMBOL(client_destroy_import);
235
236 /**
237  * Check whether or not the OSC is on MDT.
238  * In the config log,
239  * osc on MDT
240  *      setup 0:{fsname}-OSTxxxx-osc[-MDTxxxx] 1:lustre-OST0000_UUID 2:NID
241  * osc on client
242  *      setup 0:{fsname}-OSTxxxx-osc 1:lustre-OST0000_UUID 2:NID
243  *
244  **/
245 static int osc_on_mdt(char *obdname)
246 {
247         char *ptr;
248
249         ptr = strrchr(obdname, '-');
250         if (ptr == NULL)
251                 return 0;
252
253         if (strncmp(ptr + 1, "MDT", 3) == 0)
254                 return 1;
255
256         return 0;
257 }
258
259 /* Configure an RPC client OBD device.
260  *
261  * lcfg parameters:
262  * 1 - client UUID
263  * 2 - server UUID
264  * 3 - inactive-on-startup
265  * 4 - restrictive net
266  */
267 int client_obd_setup(struct obd_device *obddev, struct lustre_cfg *lcfg)
268 {
269         struct client_obd *cli = &obddev->u.cli;
270         struct obd_import *imp;
271         struct obd_uuid server_uuid;
272         int rq_portal, rp_portal, connect_op;
273         char *name = obddev->obd_type->typ_name;
274         enum ldlm_ns_type ns_type = LDLM_NS_TYPE_UNKNOWN;
275         char *cli_name = lustre_cfg_buf(lcfg, 0);
276         struct ptlrpc_connection fake_conn = { .c_self = 0,
277                                                .c_remote_uuid.uuid[0] = 0 };
278         int rc;
279         ENTRY;
280
281         /* In a more perfect world, we would hang a ptlrpc_client off of
282          * obd_type and just use the values from there. */
283         if (!strcmp(name, LUSTRE_OSC_NAME)) {
284                 rq_portal = OST_REQUEST_PORTAL;
285                 rp_portal = OSC_REPLY_PORTAL;
286                 connect_op = OST_CONNECT;
287                 cli->cl_sp_me = LUSTRE_SP_CLI;
288                 cli->cl_sp_to = LUSTRE_SP_OST;
289                 ns_type = LDLM_NS_TYPE_OSC;
290         } else if (!strcmp(name, LUSTRE_MDC_NAME) ||
291                    !strcmp(name, LUSTRE_LWP_NAME)) {
292                 rq_portal = MDS_REQUEST_PORTAL;
293                 rp_portal = MDC_REPLY_PORTAL;
294                 connect_op = MDS_CONNECT;
295                 if (is_lwp_on_ost(cli_name))
296                         cli->cl_sp_me = LUSTRE_SP_OST;
297                 else if (is_lwp_on_mdt(cli_name))
298                         cli->cl_sp_me = LUSTRE_SP_MDT;
299                 else
300                         cli->cl_sp_me = LUSTRE_SP_CLI;
301                 cli->cl_sp_to = LUSTRE_SP_MDT;
302                 ns_type = LDLM_NS_TYPE_MDC;
303         } else if (!strcmp(name, LUSTRE_OSP_NAME)) {
304                 if (strstr(lustre_cfg_buf(lcfg, 1), "OST") == NULL) {
305                         /* OSP_on_MDT for other MDTs */
306                         connect_op = MDS_CONNECT;
307                         cli->cl_sp_to = LUSTRE_SP_MDT;
308                         ns_type = LDLM_NS_TYPE_MDC;
309                         rq_portal = OUT_PORTAL;
310                 } else {
311                         /* OSP on MDT for OST */
312                         connect_op = OST_CONNECT;
313                         cli->cl_sp_to = LUSTRE_SP_OST;
314                         ns_type = LDLM_NS_TYPE_OSC;
315                         rq_portal = OST_REQUEST_PORTAL;
316                 }
317                 rp_portal = OSC_REPLY_PORTAL;
318                 cli->cl_sp_me = LUSTRE_SP_MDT;
319         } else if (!strcmp(name, LUSTRE_MGC_NAME)) {
320                 rq_portal = MGS_REQUEST_PORTAL;
321                 rp_portal = MGC_REPLY_PORTAL;
322                 connect_op = MGS_CONNECT;
323                 cli->cl_sp_me = LUSTRE_SP_MGC;
324                 cli->cl_sp_to = LUSTRE_SP_MGS;
325                 cli->cl_flvr_mgc.sf_rpc = SPTLRPC_FLVR_INVALID;
326                 ns_type = LDLM_NS_TYPE_MGC;
327         } else {
328                 CERROR("unknown client OBD type \"%s\", can't setup\n",
329                        name);
330                 RETURN(-EINVAL);
331         }
332
333         if (LUSTRE_CFG_BUFLEN(lcfg, 1) < 1) {
334                 CERROR("requires a TARGET UUID\n");
335                 RETURN(-EINVAL);
336         }
337
338         if (LUSTRE_CFG_BUFLEN(lcfg, 1) > 37) {
339                 CERROR("client UUID must be less than 38 characters\n");
340                 RETURN(-EINVAL);
341         }
342
343         if (LUSTRE_CFG_BUFLEN(lcfg, 2) < 1) {
344                 CERROR("setup requires a SERVER UUID\n");
345                 RETURN(-EINVAL);
346         }
347
348         if (LUSTRE_CFG_BUFLEN(lcfg, 2) > 37) {
349                 CERROR("target UUID must be less than 38 characters\n");
350                 RETURN(-EINVAL);
351         }
352
353         init_rwsem(&cli->cl_sem);
354         mutex_init(&cli->cl_mgc_mutex);
355         cli->cl_seq = NULL;
356         init_rwsem(&cli->cl_seq_rwsem);
357         cli->cl_conn_count = 0;
358         memcpy(server_uuid.uuid, lustre_cfg_buf(lcfg, 2),
359                min_t(unsigned int, LUSTRE_CFG_BUFLEN(lcfg, 2),
360                      sizeof(server_uuid)));
361
362         cli->cl_dirty_pages = 0;
363         cli->cl_dirty_max_pages = 0;
364         cli->cl_avail_grant = 0;
365         /* FIXME: Should limit this for the sum of all cl_dirty_max_pages. */
366         /* cl_dirty_max_pages may be changed at connect time in
367          * ptlrpc_connect_interpret(). */
368         client_adjust_max_dirty(cli);
369         INIT_LIST_HEAD(&cli->cl_cache_waiters);
370         INIT_LIST_HEAD(&cli->cl_loi_ready_list);
371         INIT_LIST_HEAD(&cli->cl_loi_hp_ready_list);
372         INIT_LIST_HEAD(&cli->cl_loi_write_list);
373         INIT_LIST_HEAD(&cli->cl_loi_read_list);
374         spin_lock_init(&cli->cl_loi_list_lock);
375         atomic_set(&cli->cl_pending_w_pages, 0);
376         atomic_set(&cli->cl_pending_r_pages, 0);
377         cli->cl_r_in_flight = 0;
378         cli->cl_w_in_flight = 0;
379
380         spin_lock_init(&cli->cl_read_rpc_hist.oh_lock);
381         spin_lock_init(&cli->cl_write_rpc_hist.oh_lock);
382         spin_lock_init(&cli->cl_read_page_hist.oh_lock);
383         spin_lock_init(&cli->cl_write_page_hist.oh_lock);
384         spin_lock_init(&cli->cl_read_offset_hist.oh_lock);
385         spin_lock_init(&cli->cl_write_offset_hist.oh_lock);
386
387         /* lru for osc. */
388         INIT_LIST_HEAD(&cli->cl_lru_osc);
389         atomic_set(&cli->cl_lru_shrinkers, 0);
390         atomic_long_set(&cli->cl_lru_busy, 0);
391         atomic_long_set(&cli->cl_lru_in_list, 0);
392         INIT_LIST_HEAD(&cli->cl_lru_list);
393         spin_lock_init(&cli->cl_lru_list_lock);
394         atomic_long_set(&cli->cl_unstable_count, 0);
395         INIT_LIST_HEAD(&cli->cl_shrink_list);
396         INIT_LIST_HEAD(&cli->cl_grant_chain);
397
398         INIT_LIST_HEAD(&cli->cl_flight_waiters);
399         cli->cl_rpcs_in_flight = 0;
400
401         init_waitqueue_head(&cli->cl_destroy_waitq);
402         atomic_set(&cli->cl_destroy_in_flight, 0);
403
404         cli->cl_supp_cksum_types = OBD_CKSUM_CRC32;
405 #ifdef ENABLE_CHECKSUM
406         /* Turn on checksumming by default. */
407         cli->cl_checksum = 1;
408         /*
409          * The supported checksum types will be worked out at connect time
410          * Set cl_chksum* to CRC32 for now to avoid returning screwed info
411          * through procfs.
412          */
413         cli->cl_cksum_type = cli->cl_supp_cksum_types;
414 #endif
415         atomic_set(&cli->cl_resends, OSC_DEFAULT_RESENDS);
416
417         /* Set it to possible maximum size. It may be reduced by ocd_brw_size
418          * from OFD after connecting. */
419         cli->cl_max_pages_per_rpc = PTLRPC_MAX_BRW_PAGES;
420
421         cli->cl_max_short_io_bytes = OBD_MAX_SHORT_IO_BYTES;
422
423         /* set cl_chunkbits default value to PAGE_SHIFT,
424          * it will be updated at OSC connection time. */
425         cli->cl_chunkbits = PAGE_SHIFT;
426
427         if (!strcmp(name, LUSTRE_MDC_NAME)) {
428                 cli->cl_max_rpcs_in_flight = OBD_MAX_RIF_DEFAULT;
429         } else if (totalram_pages >> (20 - PAGE_SHIFT) <= 128 /* MB */) {
430                 cli->cl_max_rpcs_in_flight = 2;
431         } else if (totalram_pages >> (20 - PAGE_SHIFT) <= 256 /* MB */) {
432                 cli->cl_max_rpcs_in_flight = 3;
433         } else if (totalram_pages >> (20 - PAGE_SHIFT) <= 512 /* MB */) {
434                 cli->cl_max_rpcs_in_flight = 4;
435         } else {
436                 if (osc_on_mdt(obddev->obd_name))
437                         cli->cl_max_rpcs_in_flight = OBD_MAX_RIF_MAX;
438                 else
439                         cli->cl_max_rpcs_in_flight = OBD_MAX_RIF_DEFAULT;
440         }
441
442         spin_lock_init(&cli->cl_mod_rpcs_lock);
443         spin_lock_init(&cli->cl_mod_rpcs_hist.oh_lock);
444         cli->cl_max_mod_rpcs_in_flight = 0;
445         cli->cl_mod_rpcs_in_flight = 0;
446         cli->cl_close_rpcs_in_flight = 0;
447         init_waitqueue_head(&cli->cl_mod_rpcs_waitq);
448         cli->cl_mod_tag_bitmap = NULL;
449
450         INIT_LIST_HEAD(&cli->cl_chg_dev_linkage);
451
452         if (connect_op == MDS_CONNECT) {
453                 cli->cl_max_mod_rpcs_in_flight = cli->cl_max_rpcs_in_flight - 1;
454                 OBD_ALLOC(cli->cl_mod_tag_bitmap,
455                           BITS_TO_LONGS(OBD_MAX_RIF_MAX) * sizeof(long));
456                 if (cli->cl_mod_tag_bitmap == NULL)
457                         GOTO(err, rc = -ENOMEM);
458         }
459
460         rc = ldlm_get_ref();
461         if (rc) {
462                 CERROR("ldlm_get_ref failed: %d\n", rc);
463                 GOTO(err, rc);
464         }
465
466         ptlrpc_init_client(rq_portal, rp_portal, name,
467                            &obddev->obd_ldlm_client);
468
469         imp = class_new_import(obddev);
470         if (imp == NULL)
471                 GOTO(err_ldlm, rc = -ENOENT);
472         imp->imp_client = &obddev->obd_ldlm_client;
473         imp->imp_connect_op = connect_op;
474         memcpy(cli->cl_target_uuid.uuid, lustre_cfg_buf(lcfg, 1),
475                LUSTRE_CFG_BUFLEN(lcfg, 1));
476         class_import_put(imp);
477
478         if (lustre_cfg_buf(lcfg, 4)) {
479                 __u32 refnet = libcfs_str2net(lustre_cfg_string(lcfg, 4));
480
481                 if (refnet == LNET_NIDNET(LNET_NID_ANY)) {
482                         rc = -EINVAL;
483                         CERROR("%s: bad mount option 'network=%s': rc = %d\n",
484                                obddev->obd_name, lustre_cfg_string(lcfg, 4),
485                                rc);
486                         GOTO(err_import, rc);
487                 }
488                 fake_conn.c_self = LNET_MKNID(refnet, 0);
489                 imp->imp_connection = &fake_conn;
490         }
491
492         rc = client_import_add_conn(imp, &server_uuid, 1);
493         if (rc) {
494                 CERROR("can't add initial connection\n");
495                 GOTO(err_import, rc);
496         }
497         imp->imp_connection = NULL;
498
499         cli->cl_import = imp;
500         /* cli->cl_max_mds_easize updated by mdc_init_ea_size() */
501         cli->cl_max_mds_easize = sizeof(struct lov_mds_md_v3);
502
503         if (LUSTRE_CFG_BUFLEN(lcfg, 3) > 0) {
504                 if (!strcmp(lustre_cfg_string(lcfg, 3), "inactive")) {
505                         CDEBUG(D_HA, "marking %s %s->%s as inactive\n",
506                                name, obddev->obd_name,
507                                cli->cl_target_uuid.uuid);
508                         spin_lock(&imp->imp_lock);
509                         imp->imp_deactive = 1;
510                         spin_unlock(&imp->imp_lock);
511                 }
512         }
513
514         obddev->obd_namespace = ldlm_namespace_new(obddev, obddev->obd_name,
515                                                    LDLM_NAMESPACE_CLIENT,
516                                                    LDLM_NAMESPACE_GREEDY,
517                                                    ns_type);
518         if (obddev->obd_namespace == NULL) {
519                 CERROR("Unable to create client namespace - %s\n",
520                        obddev->obd_name);
521                 GOTO(err_import, rc = -ENOMEM);
522         }
523
524         RETURN(rc);
525
526 err_import:
527         class_destroy_import(imp);
528 err_ldlm:
529         ldlm_put_ref();
530 err:
531         if (cli->cl_mod_tag_bitmap != NULL)
532                 OBD_FREE(cli->cl_mod_tag_bitmap,
533                          BITS_TO_LONGS(OBD_MAX_RIF_MAX) * sizeof(long));
534         cli->cl_mod_tag_bitmap = NULL;
535         RETURN(rc);
536
537 }
538 EXPORT_SYMBOL(client_obd_setup);
539
540 int client_obd_cleanup(struct obd_device *obddev)
541 {
542         struct client_obd *cli = &obddev->u.cli;
543         ENTRY;
544
545         ldlm_namespace_free_post(obddev->obd_namespace);
546         obddev->obd_namespace = NULL;
547
548         obd_cleanup_client_import(obddev);
549         LASSERT(obddev->u.cli.cl_import == NULL);
550
551         ldlm_put_ref();
552
553         if (cli->cl_mod_tag_bitmap != NULL)
554                 OBD_FREE(cli->cl_mod_tag_bitmap,
555                          BITS_TO_LONGS(OBD_MAX_RIF_MAX) * sizeof(long));
556         cli->cl_mod_tag_bitmap = NULL;
557
558         RETURN(0);
559 }
560 EXPORT_SYMBOL(client_obd_cleanup);
561
562 /* ->o_connect() method for client side (OSC and MDC and MGC) */
563 int client_connect_import(const struct lu_env *env,
564                           struct obd_export **exp,
565                           struct obd_device *obd, struct obd_uuid *cluuid,
566                           struct obd_connect_data *data, void *localdata)
567 {
568         struct client_obd       *cli    = &obd->u.cli;
569         struct obd_import       *imp    = cli->cl_import;
570         struct obd_connect_data *ocd;
571         struct lustre_handle    conn    = { 0 };
572         int                     rc;
573         ENTRY;
574
575         *exp = NULL;
576         down_write(&cli->cl_sem);
577         if (cli->cl_conn_count > 0)
578                 GOTO(out_sem, rc = -EALREADY);
579
580         rc = class_connect(&conn, obd, cluuid);
581         if (rc)
582                 GOTO(out_sem, rc);
583
584         cli->cl_conn_count++;
585         *exp = class_conn2export(&conn);
586
587         LASSERT(obd->obd_namespace);
588
589         imp->imp_dlm_handle = conn;
590         rc = ptlrpc_init_import(imp);
591         if (rc != 0)
592                 GOTO(out_ldlm, rc);
593
594         ocd = &imp->imp_connect_data;
595         if (data) {
596                 *ocd = *data;
597                 imp->imp_connect_flags_orig = data->ocd_connect_flags;
598                 imp->imp_connect_flags2_orig = data->ocd_connect_flags2;
599         }
600
601         rc = ptlrpc_connect_import(imp);
602         if (rc != 0) {
603                 LASSERT(imp->imp_state == LUSTRE_IMP_DISCON);
604                 GOTO(out_ldlm, rc);
605         }
606         LASSERT(*exp != NULL && (*exp)->exp_connection);
607
608         if (data) {
609                 LASSERTF((ocd->ocd_connect_flags & data->ocd_connect_flags) ==
610                          ocd->ocd_connect_flags, "old %#llx, new %#llx\n",
611                          data->ocd_connect_flags, ocd->ocd_connect_flags);
612                 data->ocd_connect_flags = ocd->ocd_connect_flags;
613                 data->ocd_connect_flags2 = ocd->ocd_connect_flags2;
614         }
615
616         ptlrpc_pinger_add_import(imp);
617
618         EXIT;
619
620         if (rc) {
621 out_ldlm:
622                 cli->cl_conn_count--;
623                 class_disconnect(*exp);
624                 *exp = NULL;
625         }
626 out_sem:
627         up_write(&cli->cl_sem);
628
629         if (!rc && localdata) {
630                 LASSERT(cli->cl_cache == NULL); /* only once */
631                 cli->cl_cache = (struct cl_client_cache *)localdata;
632                 cl_cache_incref(cli->cl_cache);
633                 cli->cl_lru_left = &cli->cl_cache->ccc_lru_left;
634
635                 /* add this osc into entity list */
636                 LASSERT(list_empty(&cli->cl_lru_osc));
637                 spin_lock(&cli->cl_cache->ccc_lru_lock);
638                 list_add(&cli->cl_lru_osc, &cli->cl_cache->ccc_lru);
639                 spin_unlock(&cli->cl_cache->ccc_lru_lock);
640         }
641
642         return rc;
643 }
644 EXPORT_SYMBOL(client_connect_import);
645
646 int client_disconnect_export(struct obd_export *exp)
647 {
648         struct obd_device *obd = class_exp2obd(exp);
649         struct client_obd *cli;
650         struct obd_import *imp;
651         int rc = 0, err;
652         ENTRY;
653
654         if (!obd) {
655                 CERROR("invalid export for disconnect: exp %p cookie %#llx\n",
656                        exp, exp ? exp->exp_handle.h_cookie : -1);
657                 RETURN(-EINVAL);
658         }
659
660         cli = &obd->u.cli;
661         imp = cli->cl_import;
662
663         down_write(&cli->cl_sem);
664         CDEBUG(D_INFO, "disconnect %s - %zu\n", obd->obd_name,
665                 cli->cl_conn_count);
666
667         if (cli->cl_conn_count == 0) {
668                 CERROR("disconnecting disconnected device (%s)\n",
669                        obd->obd_name);
670                 GOTO(out_disconnect, rc = -EINVAL);
671         }
672
673         cli->cl_conn_count--;
674         if (cli->cl_conn_count != 0)
675                 GOTO(out_disconnect, rc = 0);
676
677         /* Mark import deactivated now, so we don't try to reconnect if any
678          * of the cleanup RPCs fails (e.g. LDLM cancel, etc).  We don't
679          * fully deactivate the import, or that would drop all requests. */
680         spin_lock(&imp->imp_lock);
681         imp->imp_deactive = 1;
682         spin_unlock(&imp->imp_lock);
683
684         /* Some non-replayable imports (MDS's OSCs) are pinged, so just
685          * delete it regardless.  (It's safe to delete an import that was
686          * never added.) */
687         (void)ptlrpc_pinger_del_import(imp);
688
689         if (obd->obd_namespace != NULL) {
690                 /* obd_force == local only */
691                 ldlm_cli_cancel_unused(obd->obd_namespace, NULL,
692                                        obd->obd_force ? LCF_LOCAL : 0, NULL);
693                 ldlm_namespace_free_prior(obd->obd_namespace, imp, obd->obd_force);
694         }
695
696         /* There's no need to hold sem while disconnecting an import,
697          * and it may actually cause deadlock in GSS. */
698         up_write(&cli->cl_sem);
699         rc = ptlrpc_disconnect_import(imp, 0);
700         down_write(&cli->cl_sem);
701
702         ptlrpc_invalidate_import(imp);
703
704         EXIT;
705
706 out_disconnect:
707         /* Use server style - class_disconnect should be always called for
708          * o_disconnect. */
709         err = class_disconnect(exp);
710         if (!rc && err)
711                 rc = err;
712
713         up_write(&cli->cl_sem);
714
715         RETURN(rc);
716 }
717 EXPORT_SYMBOL(client_disconnect_export);
718
719 #ifdef HAVE_SERVER_SUPPORT
720 int server_disconnect_export(struct obd_export *exp)
721 {
722         int rc;
723         ENTRY;
724
725         /* Disconnect early so that clients can't keep using export. */
726         rc = class_disconnect(exp);
727         /* Close import to avoid sending any requests. */
728         if (exp->exp_imp_reverse)
729                 ptlrpc_cleanup_imp(exp->exp_imp_reverse);
730
731         ldlm_bl_thread_wakeup();
732
733         /* complete all outstanding replies */
734         spin_lock(&exp->exp_lock);
735         while (!list_empty(&exp->exp_outstanding_replies)) {
736                 struct ptlrpc_reply_state *rs =
737                         list_entry(exp->exp_outstanding_replies.next,
738                                        struct ptlrpc_reply_state, rs_exp_list);
739                 struct ptlrpc_service_part *svcpt = rs->rs_svcpt;
740
741                 spin_lock(&svcpt->scp_rep_lock);
742
743                 list_del_init(&rs->rs_exp_list);
744
745                 spin_lock(&rs->rs_lock);
746                 /* clear rs_convert_lock to make sure rs is handled and put */
747                 rs->rs_convert_lock = 0;
748                 ptlrpc_schedule_difficult_reply(rs);
749                 spin_unlock(&rs->rs_lock);
750
751                 spin_unlock(&svcpt->scp_rep_lock);
752         }
753         spin_unlock(&exp->exp_lock);
754
755         RETURN(rc);
756 }
757 EXPORT_SYMBOL(server_disconnect_export);
758
759 /* --------------------------------------------------------------------------
760  * from old lib/target.c
761  * -------------------------------------------------------------------------- */
762
763 static int target_handle_reconnect(struct lustre_handle *conn,
764                                    struct obd_export *exp,
765                                    struct obd_uuid *cluuid)
766 {
767         struct obd_device *target;
768         struct lustre_handle *hdl;
769         ktime_t remaining;
770         s64 timeout;
771         int rc = 0;
772
773         ENTRY;
774         hdl = &exp->exp_imp_reverse->imp_remote_handle;
775         if (!exp->exp_connection || !lustre_handle_is_used(hdl)) {
776                 conn->cookie = exp->exp_handle.h_cookie;
777                 CDEBUG(D_HA, "connect export for UUID '%s' at %p,"
778                        " cookie %#llx\n", cluuid->uuid, exp, conn->cookie);
779                 RETURN(0);
780         }
781
782         target = exp->exp_obd;
783
784         /* Might be a re-connect after a partition. */
785         if (memcmp(&conn->cookie, &hdl->cookie, sizeof conn->cookie)) {
786                 LCONSOLE_WARN("%s: already connected client %s (at %s) "
787                               "with handle %#llx. Rejecting client "
788                               "with the same UUID trying to reconnect "
789                               "with handle %#llx\n", target->obd_name,
790                               obd_uuid2str(&exp->exp_client_uuid),
791                               obd_export_nid2str(exp),
792                               hdl->cookie, conn->cookie);
793                 memset(conn, 0, sizeof *conn);
794                 /* target_handle_connect() treats EALREADY and
795                  * -EALREADY differently.  -EALREADY is an error
796                  * (same UUID, different handle). */
797                 RETURN(-EALREADY);
798         }
799
800         if (!target->obd_recovering) {
801                 LCONSOLE_WARN("%s: Client %s (at %s) reconnecting\n",
802                         target->obd_name, obd_uuid2str(&exp->exp_client_uuid),
803                         obd_export_nid2str(exp));
804                 GOTO(out_already, rc);
805         }
806
807         remaining = hrtimer_expires_remaining(&target->obd_recovery_timer);
808         timeout = ktime_divns(remaining, NSEC_PER_SEC);
809         if (timeout > 0) {
810                 LCONSOLE_WARN("%s: Client %s (at %s) reconnected, waiting for %d clients in recovery for %lld:%.02lld\n",
811                               target->obd_name,
812                               obd_uuid2str(&exp->exp_client_uuid),
813                               obd_export_nid2str(exp),
814                               target->obd_max_recoverable_clients,
815                               timeout / 60, timeout % 60);
816         } else {
817                 struct target_distribute_txn_data *tdtd;
818                 int size = 0;
819                 int count = 0;
820                 char *buf = NULL;
821
822                 tdtd = class_exp2tgt(exp)->lut_tdtd;
823                 if (tdtd && tdtd->tdtd_show_update_logs_retrievers)
824                         buf = tdtd->tdtd_show_update_logs_retrievers(
825                                 tdtd->tdtd_show_retrievers_cbdata,
826                                 &size, &count);
827
828                 if (count > 0)
829                         LCONSOLE_WARN("%s: Client %s (at %s) reconnecting, waiting for %d MDTs (%s) in recovery for %lld:%.02lld. Please wait until all MDTs recovered or you may force MDT evicition via 'lctl --device %s abort_recovery.\n",
830                                       target->obd_name,
831                                       obd_uuid2str(&exp->exp_client_uuid),
832                                       obd_export_nid2str(exp), count,
833                                       buf ? buf : "unknown (not enough RAM)",
834                                       (abs(timeout) + target->obd_recovery_timeout) / 60,
835                                       (abs(timeout) + target->obd_recovery_timeout) % 60,
836                                       target->obd_name);
837                 else
838                         LCONSOLE_WARN("%s: Recovery already passed deadline %lld:%.02lld. If you do not want to wait more, you may force taget eviction via 'lctl --device %s abort_recovery.\n",
839                                       target->obd_name, abs(timeout) / 60,
840                                       abs(timeout) % 60, target->obd_name);
841
842                 if (buf != NULL)
843                         OBD_FREE(buf, size);
844         }
845
846 out_already:
847         conn->cookie = exp->exp_handle.h_cookie;
848         /* target_handle_connect() treats EALREADY and
849          * -EALREADY differently.  EALREADY means we are
850          * doing a valid reconnect from the same client. */
851         RETURN(EALREADY);
852 }
853
854 static void
855 check_and_start_recovery_timer(struct obd_device *obd,
856                                struct ptlrpc_request *req, int new_client);
857
858 /**
859  * update flags for import during reconnect process
860  */
861 static int rev_import_flags_update(struct obd_import *revimp,
862                                    struct ptlrpc_request *req)
863 {
864         int rc;
865         struct obd_connect_data *data;
866
867         data = req_capsule_client_get(&req->rq_pill, &RMF_CONNECT_DATA);
868
869         if (data->ocd_connect_flags & OBD_CONNECT_AT)
870                 revimp->imp_msghdr_flags |= MSGHDR_AT_SUPPORT;
871         else
872                 revimp->imp_msghdr_flags &= ~MSGHDR_AT_SUPPORT;
873
874         revimp->imp_msghdr_flags |= MSGHDR_CKSUM_INCOMPAT18;
875
876         rc = sptlrpc_import_sec_adapt(revimp, req->rq_svc_ctx, &req->rq_flvr);
877         if (rc) {
878                 CERROR("%s: cannot get reverse import %s security: rc = %d\n",
879                         revimp->imp_client->cli_name,
880                         libcfs_id2str(req->rq_peer), rc);
881                 return rc;
882         }
883
884         return 0;
885 }
886
887 /**
888  * Allocate a new reverse import for an export.
889  *
890  * \retval -errno in case error hit
891  * \retval 0 if reverse import correctly init
892  **/
893 int rev_import_init(struct obd_export *export)
894 {
895         struct obd_device *obd = export->exp_obd;
896         struct obd_import *revimp;
897
898         LASSERT(export->exp_imp_reverse == NULL);
899
900         revimp = class_new_import(obd);
901         if (revimp == NULL)
902                 return -ENOMEM;
903
904         revimp->imp_remote_handle.cookie = 0ULL;
905         revimp->imp_client = &obd->obd_ldlm_client;
906         revimp->imp_dlm_fake = 1;
907
908         /* it is safe to connect import in new state as no sends possible */
909         spin_lock(&export->exp_lock);
910         export->exp_imp_reverse = revimp;
911         spin_unlock(&export->exp_lock);
912         class_import_put(revimp);
913
914         return 0;
915 }
916 EXPORT_SYMBOL(rev_import_init);
917
918 /**
919  * Handle reconnect for an export.
920  *
921  * \param exp export to handle reconnect process
922  * \param req client reconnect request
923  *
924  * \retval -rc in case securitfy flavor can't be changed
925  * \retval 0 in case none problems
926  */
927 static int rev_import_reconnect(struct obd_export *exp,
928                                 struct ptlrpc_request *req)
929 {
930         struct obd_import *revimp = exp->exp_imp_reverse;
931         struct lustre_handle *lh;
932         int rc;
933
934         /* avoid sending a request until import flags are changed */
935         ptlrpc_import_enter_resend(revimp);
936
937         if (revimp->imp_connection != NULL)
938                 ptlrpc_connection_put(revimp->imp_connection);
939
940         /*
941          * client from recovery don't have a handle so we need to take from
942          * request. it may produce situation when wrong client connected
943          * to recovery as we trust a client uuid
944          */
945         lh = req_capsule_client_get(&req->rq_pill, &RMF_CONN);
946         revimp->imp_remote_handle = *lh;
947
948         /* unknown versions will be caught in
949          * ptlrpc_handle_server_req_in->lustre_unpack_msg() */
950         revimp->imp_msg_magic = req->rq_reqmsg->lm_magic;
951
952         revimp->imp_connection = ptlrpc_connection_addref(exp->exp_connection);
953
954         rc = rev_import_flags_update(revimp, req);
955         if (rc != 0) {
956                 /* it is safe to still be in RECOVERY phase as we are not able
957                  * to setup correct security flavor so requests are not able to
958                  * be delivered correctly */
959                 return rc;
960         }
961
962         /* resend all rpc's via new connection */
963         return ptlrpc_import_recovery_state_machine(revimp);
964 }
965
966 int target_handle_connect(struct ptlrpc_request *req)
967 {
968         struct obd_device *target = NULL;
969         struct obd_export *export = NULL;
970         /* connect handle - filled from target_handle_reconnect in
971          * reconnect case */
972         struct lustre_handle conn;
973         struct lustre_handle *tmp;
974         struct obd_uuid cluuid;
975         char *str;
976         int rc = 0;
977         char *target_start;
978         int target_len;
979         bool     mds_conn = false, lw_client = false, initial_conn = false;
980         bool     mds_mds_conn = false;
981         bool     new_mds_mds_conn = false;
982         struct obd_connect_data *data, *tmpdata;
983         int size, tmpsize;
984         lnet_nid_t *client_nid = NULL;
985         ENTRY;
986
987         OBD_RACE(OBD_FAIL_TGT_CONN_RACE);
988
989         str = req_capsule_client_get(&req->rq_pill, &RMF_TGTUUID);
990         if (str == NULL) {
991                 DEBUG_REQ(D_ERROR, req, "bad target UUID for connect");
992                 GOTO(out, rc = -EINVAL);
993         }
994
995         target = class_dev_by_str(str);
996         if (!target) {
997                 deuuidify(str, NULL, &target_start, &target_len);
998                 LCONSOLE_ERROR_MSG(0x137, "%s: not available for connect "
999                                    "from %s (no target). If you are running "
1000                                    "an HA pair check that the target is "
1001                                    "mounted on the other server.\n", str,
1002                                    libcfs_nid2str(req->rq_peer.nid));
1003                 GOTO(out, rc = -ENODEV);
1004         }
1005
1006         spin_lock(&target->obd_dev_lock);
1007
1008         target->obd_conn_inprogress++;
1009
1010         if (target->obd_stopping || !target->obd_set_up) {
1011                 spin_unlock(&target->obd_dev_lock);
1012
1013                 deuuidify(str, NULL, &target_start, &target_len);
1014                 LCONSOLE_INFO("%.*s: Not available for connect from %s (%s)\n",
1015                               target_len, target_start,
1016                               libcfs_nid2str(req->rq_peer.nid),
1017                               (target->obd_stopping ?
1018                                "stopping" : "not set up"));
1019                 GOTO(out, rc = -ENODEV);
1020         }
1021
1022         if (target->obd_no_conn) {
1023                 spin_unlock(&target->obd_dev_lock);
1024
1025                 CDEBUG(D_INFO, "%s: Temporarily refusing client connection "
1026                                "from %s\n", target->obd_name,
1027                                libcfs_nid2str(req->rq_peer.nid));
1028                 GOTO(out, rc = -EAGAIN);
1029         }
1030
1031         spin_unlock(&target->obd_dev_lock);
1032
1033         str = req_capsule_client_get(&req->rq_pill, &RMF_CLUUID);
1034         if (str == NULL) {
1035                 DEBUG_REQ(D_ERROR, req, "bad client UUID for connect");
1036                 GOTO(out, rc = -EINVAL);
1037         }
1038
1039         obd_str2uuid(&cluuid, str);
1040
1041         tmp = req_capsule_client_get(&req->rq_pill, &RMF_CONN);
1042         if (tmp == NULL)
1043                 GOTO(out, rc = -EPROTO);
1044
1045         conn = *tmp;
1046
1047         size = req_capsule_get_size(&req->rq_pill, &RMF_CONNECT_DATA,
1048                                     RCL_CLIENT);
1049         data = req_capsule_client_get(&req->rq_pill, &RMF_CONNECT_DATA);
1050         if (!data)
1051                 GOTO(out, rc = -EPROTO);
1052
1053         rc = req_capsule_server_pack(&req->rq_pill);
1054         if (rc)
1055                 GOTO(out, rc);
1056
1057 #if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 0, 53, 0)
1058         /* Don't allow clients to connect that are using old 1.8 format
1059          * protocol conventions (LUSTRE_MSG_MAGIC_v1, !MSGHDR_CKSUM_INCOMPAT18,
1060          * ldlm_flock_policy_wire format, MDT_ATTR_xTIME_SET, etc).  The
1061          * FULL20 flag should be set on all connections since 2.0, but no
1062          * longer affects behaviour.
1063          *
1064          * Later this check will be disabled and the flag can be retired
1065          * completely once interop with 3.0 is no longer needed.
1066          */
1067         if (!(data->ocd_connect_flags & OBD_CONNECT_FULL20))
1068                 GOTO(out, rc = -EPROTO);
1069
1070         /* Don't allow liblustre clients to connect.
1071          * - testing was disabled in v2_2_50_0-61-g6a75d65
1072          * - building was disabled in v2_5_58_0-28-g7277179
1073          * - client code was deleted in v2_6_50_0-101-gcdfbc72,
1074          * - clients were refused connect for version difference > 0.0.1.32  */
1075         if (lustre_msg_get_op_flags(req->rq_reqmsg) & MSG_CONNECT_LIBCLIENT) {
1076                 DEBUG_REQ(D_WARNING, req, "Refusing libclient connection");
1077                 GOTO(out, rc = -EPROTO);
1078         }
1079 #endif
1080
1081         /* Note: lw_client is needed in MDS-MDS failover during update log
1082          * processing, so we needs to allow lw_client to be connected at
1083          * anytime, instead of only the initial connection */
1084         lw_client = (data->ocd_connect_flags & OBD_CONNECT_LIGHTWEIGHT) != 0;
1085
1086         if (lustre_msg_get_op_flags(req->rq_reqmsg) & MSG_CONNECT_INITIAL) {
1087                 initial_conn = true;
1088                 mds_conn = (data->ocd_connect_flags & OBD_CONNECT_MDS) != 0;
1089                 mds_mds_conn = (data->ocd_connect_flags &
1090                                 OBD_CONNECT_MDS_MDS) != 0;
1091
1092                 /* OBD_CONNECT_MNE_SWAB is defined as OBD_CONNECT_MDS_MDS
1093                  * for Imperative Recovery connection from MGC to MGS.
1094                  *
1095                  * Via check OBD_CONNECT_FID, we can distinguish whether
1096                  * the OBD_CONNECT_MDS_MDS/OBD_CONNECT_MNE_SWAB is from
1097                  * MGC or MDT, since MGC does not use OBD_CONNECT_FID.
1098                  */
1099                 if (!lw_client &&
1100                     (data->ocd_connect_flags & OBD_CONNECT_MDS_MDS) &&
1101                     (data->ocd_connect_flags & OBD_CONNECT_FID) &&
1102                     (data->ocd_connect_flags & OBD_CONNECT_VERSION)) {
1103                         __u32 major = OBD_OCD_VERSION_MAJOR(data->ocd_version);
1104                         __u32 minor = OBD_OCD_VERSION_MINOR(data->ocd_version);
1105                         __u32 patch = OBD_OCD_VERSION_PATCH(data->ocd_version);
1106
1107                         /* We do not support the MDT-MDT interoperations with
1108                          * different version MDT because of protocol changes. */
1109                         if (unlikely(major != LUSTRE_MAJOR ||
1110                                      minor != LUSTRE_MINOR ||
1111                                      abs(patch - LUSTRE_PATCH) > 3)) {
1112                                 LCONSOLE_WARN("%s (%u.%u.%u.%u) refused the "
1113                                         "connection from different version MDT "
1114                                         "(%d.%d.%d.%d) %s %s\n",
1115                                         target->obd_name, LUSTRE_MAJOR,
1116                                         LUSTRE_MINOR, LUSTRE_PATCH, LUSTRE_FIX,
1117                                         major, minor, patch,
1118                                         OBD_OCD_VERSION_FIX(data->ocd_version),
1119                                         libcfs_nid2str(req->rq_peer.nid), str);
1120
1121                                 GOTO(out, rc = -EPROTO);
1122                         }
1123                 }
1124         }
1125
1126         /* lctl gets a backstage, all-access pass. */
1127         if (obd_uuid_equals(&cluuid, &target->obd_uuid))
1128                 goto dont_check_exports;
1129
1130         export = cfs_hash_lookup(target->obd_uuid_hash, &cluuid);
1131         if (!export)
1132                 goto no_export;
1133
1134         /* We've found an export in the hash. */
1135
1136         spin_lock(&export->exp_lock);
1137
1138         if (export->exp_connecting) { /* bug 9635, et. al. */
1139                 spin_unlock(&export->exp_lock);
1140                 LCONSOLE_WARN("%s: Export %p already connecting from %s\n",
1141                               export->exp_obd->obd_name, export,
1142                               libcfs_nid2str(req->rq_peer.nid));
1143                 class_export_put(export);
1144                 export = NULL;
1145                 rc = -EALREADY;
1146         } else if ((mds_conn || (lw_client && initial_conn) ||
1147                    data->ocd_connect_flags & OBD_CONNECT_MDS_MDS) &&
1148                    export->exp_connection != NULL) {
1149                 spin_unlock(&export->exp_lock);
1150                 if (req->rq_peer.nid != export->exp_connection->c_peer.nid) {
1151                         /* MDS or LWP reconnected after failover. */
1152                         LCONSOLE_WARN("%s: Received %s connection from "
1153                             "%s, removing former export from %s\n",
1154                             target->obd_name, mds_conn ? "MDS" : "LWP",
1155                             libcfs_nid2str(req->rq_peer.nid),
1156                             libcfs_nid2str(export->exp_connection->c_peer.nid));
1157                 } else {
1158                         /* New MDS connection from the same NID. */
1159                         LCONSOLE_WARN("%s: Received new %s connection from "
1160                                 "%s, removing former export from same NID\n",
1161                                 target->obd_name, mds_conn ? "MDS" : "LWP",
1162                                 libcfs_nid2str(req->rq_peer.nid));
1163                 }
1164
1165                 if (req->rq_peer.nid == export->exp_connection->c_peer.nid &&
1166                     data->ocd_connect_flags & OBD_CONNECT_MDS_MDS) {
1167                         /* Because exports between MDTs will always be
1168                          * kept, let's do not fail such export if they
1169                          * come from the same NID, otherwise it might
1170                          * cause eviction between MDTs, which might
1171                          * cause namespace inconsistency */
1172                         spin_lock(&export->exp_lock);
1173                         export->exp_connecting = 1;
1174                         export->exp_conn_cnt = 0;
1175                         spin_unlock(&export->exp_lock);
1176                         conn.cookie = export->exp_handle.h_cookie;
1177                         rc = EALREADY;
1178                 } else {
1179                         class_fail_export(export);
1180                         class_export_put(export);
1181                         export = NULL;
1182                         rc = 0;
1183                 }
1184         } else if (export->exp_connection != NULL && initial_conn &&
1185                    req->rq_peer.nid != export->exp_connection->c_peer.nid) {
1186                 spin_unlock(&export->exp_lock);
1187                 /* In MDS failover we have static UUID but NID can change. */
1188                 LCONSOLE_WARN("%s: Client %s seen on new nid %s when "
1189                               "existing nid %s is already connected\n",
1190                               target->obd_name, cluuid.uuid,
1191                               libcfs_nid2str(req->rq_peer.nid),
1192                               libcfs_nid2str(
1193                                       export->exp_connection->c_peer.nid));
1194                 rc = -EALREADY;
1195                 class_export_put(export);
1196                 export = NULL;
1197         } else {
1198                 export->exp_connecting = 1;
1199                 spin_unlock(&export->exp_lock);
1200                 LASSERT(export->exp_obd == target);
1201
1202                 rc = target_handle_reconnect(&conn, export, &cluuid);
1203         }
1204
1205         /* If we found an export, we already unlocked. */
1206         if (!export) {
1207 no_export:
1208                 OBD_FAIL_TIMEOUT(OBD_FAIL_TGT_DELAY_CONNECT, 2 * obd_timeout);
1209         } else if (req->rq_export == NULL &&
1210                    atomic_read(&export->exp_rpc_count) > 0) {
1211                 LCONSOLE_WARN("%s: Client %s (at %s) refused connection, "
1212                               "still busy with %d references\n",
1213                               target->obd_name, cluuid.uuid,
1214                               libcfs_nid2str(req->rq_peer.nid),
1215                               atomic_read(&export->exp_refcount));
1216                         GOTO(out, rc = -EBUSY);
1217         } else if (lustre_msg_get_conn_cnt(req->rq_reqmsg) == 1 &&
1218                    rc != EALREADY) {
1219                 if (!strstr(cluuid.uuid, "mdt"))
1220                         LCONSOLE_WARN("%s: Rejecting reconnect from the "
1221                                       "known client %s (at %s) because it "
1222                                       "is indicating it is a new client",
1223                                       target->obd_name, cluuid.uuid,
1224                                       libcfs_nid2str(req->rq_peer.nid));
1225                 GOTO(out, rc = -EALREADY);
1226         } else {
1227                 OBD_FAIL_TIMEOUT(OBD_FAIL_TGT_DELAY_RECONNECT, 2 * obd_timeout);
1228         }
1229
1230         if (rc < 0) {
1231                 GOTO(out, rc);
1232         }
1233
1234         CDEBUG(D_HA, "%s: connection from %s@%s %st%llu exp %p cur %lld last %lld\n",
1235                target->obd_name, cluuid.uuid, libcfs_nid2str(req->rq_peer.nid),
1236                target->obd_recovering ? "recovering/" : "", data->ocd_transno,
1237                export, ktime_get_real_seconds(),
1238                export ? export->exp_last_request_time : 0);
1239
1240         /* If this is the first time a client connects, reset the recovery
1241          * timer. Discard lightweight connections which might be local. */
1242         if (!lw_client && rc == 0 && target->obd_recovering)
1243                 check_and_start_recovery_timer(target, req, export == NULL);
1244
1245         /* We want to handle EALREADY but *not* -EALREADY from
1246          * target_handle_reconnect(), return reconnection state in a flag. */
1247         if (rc == EALREADY) {
1248                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_RECONNECT);
1249                 rc = 0;
1250         } else {
1251                 LASSERT(rc == 0);
1252         }
1253
1254         /* Tell the client if we support replayable requests. */
1255         if (target->obd_replayable)
1256                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_REPLAYABLE);
1257         client_nid = &req->rq_peer.nid;
1258
1259         if (export == NULL) {
1260                 /* allow lightweight connections during recovery */
1261                 /* allow "new" MDT to be connected during recovery, since we
1262                  * need retrieve recovery update records from it */
1263                 if (target->obd_recovering && !lw_client && !mds_mds_conn) {
1264                         struct hrtimer *timer = &target->obd_recovery_timer;
1265                         ktime_t remaining;
1266                         s64 timeout, left;
1267                         int in_progress;
1268                         int connected;
1269                         int known;
1270                         int stale;
1271                         char *msg;
1272
1273                         connected = atomic_read(&target->obd_connected_clients);
1274                         in_progress = atomic_read(&target->obd_lock_replay_clients);
1275                         known = target->obd_max_recoverable_clients;
1276                         stale = target->obd_stale_clients;
1277                         remaining = hrtimer_expires_remaining(timer);
1278                         left = ktime_divns(remaining, NSEC_PER_SEC);
1279                         if (ktime_to_ns(remaining) > 0) {
1280                                 msg = "to recover in";
1281                                 timeout = left;
1282                         } else {
1283                                 msg = "already passed deadline";
1284                                 timeout = -left;
1285                         }
1286
1287                         LCONSOLE_WARN("%s: Denying connection for new client %s (at %s), waiting for %d known clients (%d recovered, %d in progress, and %d evicted) %s %lld:%.02lld\n",
1288                                       target->obd_name, cluuid.uuid,
1289                                       libcfs_nid2str(req->rq_peer.nid), known,
1290                                       connected - in_progress, in_progress,
1291                                       stale, msg, timeout / 60, timeout % 60);
1292                         rc = -EBUSY;
1293                 } else {
1294 dont_check_exports:
1295                         rc = obd_connect(req->rq_svc_thread->t_env,
1296                                          &export, target, &cluuid, data,
1297                                          client_nid);
1298                         if (mds_conn && OBD_FAIL_CHECK(OBD_FAIL_TGT_RCVG_FLAG))
1299                                 lustre_msg_add_op_flags(req->rq_repmsg,
1300                                                         MSG_CONNECT_RECOVERING);
1301                         if (rc == 0) {
1302                                 conn.cookie = export->exp_handle.h_cookie;
1303                                 rc = rev_import_init(export);
1304                         }
1305
1306                         if (mds_mds_conn)
1307                                 new_mds_mds_conn = true;
1308                 }
1309         } else {
1310                 rc = obd_reconnect(req->rq_svc_thread->t_env,
1311                                    export, target, &cluuid, data, client_nid);
1312         }
1313         if (rc)
1314                 GOTO(out, rc);
1315
1316         LASSERT(target->u.obt.obt_magic == OBT_MAGIC);
1317         data->ocd_instance = target->u.obt.obt_instance;
1318
1319         /* Return only the parts of obd_connect_data that we understand, so the
1320          * client knows that we don't understand the rest. */
1321         if (data) {
1322                 tmpsize = req_capsule_get_size(&req->rq_pill, &RMF_CONNECT_DATA,
1323                                                RCL_SERVER);
1324                 tmpdata = req_capsule_server_get(&req->rq_pill,
1325                                                  &RMF_CONNECT_DATA);
1326                 /* Don't use struct assignment here, because the client reply
1327                  * buffer may be smaller/larger than the local struct
1328                  * obd_connect_data. */
1329                 memcpy(tmpdata, data, min(tmpsize, size));
1330         }
1331
1332         /* If the client and the server are the same node, we will already
1333          * have an export that really points to the client's DLM export,
1334          * because we have a shared handles table.
1335          *
1336          * XXX this will go away when shaver stops sending the "connect" handle
1337          * in the real "remote handle" field of the request --phik 24 Apr 2003
1338          */
1339         ptlrpc_request_change_export(req, export);
1340
1341         spin_lock(&export->exp_lock);
1342         if (export->exp_conn_cnt >= lustre_msg_get_conn_cnt(req->rq_reqmsg)) {
1343                 spin_unlock(&export->exp_lock);
1344                 CDEBUG(D_RPCTRACE, "%s: %s already connected at greater "
1345                        "or equal conn_cnt: %d >= %d\n",
1346                        cluuid.uuid, libcfs_nid2str(req->rq_peer.nid),
1347                        export->exp_conn_cnt,
1348                        lustre_msg_get_conn_cnt(req->rq_reqmsg));
1349
1350                 GOTO(out, rc = -EALREADY);
1351         }
1352         LASSERT(lustre_msg_get_conn_cnt(req->rq_reqmsg) > 0);
1353         export->exp_conn_cnt = lustre_msg_get_conn_cnt(req->rq_reqmsg);
1354         spin_unlock(&export->exp_lock);
1355
1356         if (export->exp_connection != NULL) {
1357                 /* Check to see if connection came from another NID. */
1358                 if ((export->exp_connection->c_peer.nid != req->rq_peer.nid) &&
1359                     !hlist_unhashed(&export->exp_nid_hash))
1360                         cfs_hash_del(export->exp_obd->obd_nid_hash,
1361                                      &export->exp_connection->c_peer.nid,
1362                                      &export->exp_nid_hash);
1363
1364                 ptlrpc_connection_put(export->exp_connection);
1365         }
1366
1367         export->exp_connection = ptlrpc_connection_get(req->rq_peer,
1368                                                        req->rq_self,
1369                                                        &cluuid);
1370         if (hlist_unhashed(&export->exp_nid_hash))
1371                 cfs_hash_add(export->exp_obd->obd_nid_hash,
1372                              &export->exp_connection->c_peer.nid,
1373                              &export->exp_nid_hash);
1374
1375         lustre_msg_set_handle(req->rq_repmsg, &conn);
1376
1377         rc = rev_import_reconnect(export, req);
1378         if (rc != 0)
1379                 GOTO(out, rc);
1380
1381         if (target->obd_recovering && !export->exp_in_recovery && !lw_client) {
1382                 int has_transno;
1383                 __u64 transno = data->ocd_transno;
1384
1385                 spin_lock(&export->exp_lock);
1386                 /* possible race with class_disconnect_stale_exports,
1387                  * export may be already in the eviction process */
1388                 if (export->exp_failed) {
1389                         spin_unlock(&export->exp_lock);
1390                         GOTO(out, rc = -ENODEV);
1391                 }
1392                 export->exp_in_recovery = 1;
1393                 export->exp_req_replay_needed = 1;
1394                 export->exp_lock_replay_needed = 1;
1395                 spin_unlock(&export->exp_lock);
1396
1397                 has_transno = !!(lustre_msg_get_op_flags(req->rq_reqmsg) &
1398                                  MSG_CONNECT_TRANSNO);
1399                 if (has_transno && transno == 0)
1400                         CWARN("Connect with zero transno!\n");
1401
1402                 if (has_transno && transno > 0 &&
1403                     transno < target->obd_next_recovery_transno &&
1404                     transno > target->obd_last_committed) {
1405                         /* Another way is to use cmpxchg() to be lock-free. */
1406                         spin_lock(&target->obd_recovery_task_lock);
1407                         if (transno < target->obd_next_recovery_transno)
1408                                 target->obd_next_recovery_transno = transno;
1409                         spin_unlock(&target->obd_recovery_task_lock);
1410                 }
1411
1412                 atomic_inc(&target->obd_req_replay_clients);
1413                 atomic_inc(&target->obd_lock_replay_clients);
1414                 /* Note: MDS-MDS connection is allowed to be connected during
1415                  * recovery, no matter if the exports needs to be recoveried.
1416                  * Because we need retrieve updates logs from all other MDTs.
1417                  * So if the MDS-MDS export is new, obd_max_recoverable_clients
1418                  * also needs to be increased to match other recovery checking
1419                  * condition. */
1420                 if (new_mds_mds_conn)
1421                         target->obd_max_recoverable_clients++;
1422                 if (atomic_inc_return(&target->obd_connected_clients) ==
1423                     target->obd_max_recoverable_clients)
1424                         wake_up(&target->obd_next_transno_waitq);
1425         }
1426
1427         /* Tell the client we're in recovery, when client is involved in it. */
1428         if (target->obd_recovering && !lw_client)
1429                 lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_RECOVERING);
1430
1431 out:
1432         if (export) {
1433                 spin_lock(&export->exp_lock);
1434                 export->exp_connecting = 0;
1435                 spin_unlock(&export->exp_lock);
1436
1437                 class_export_put(export);
1438         }
1439         if (target != NULL) {
1440                 spin_lock(&target->obd_dev_lock);
1441                 target->obd_conn_inprogress--;
1442                 spin_unlock(&target->obd_dev_lock);
1443                 class_decref(target, "find", current);
1444         }
1445         req->rq_status = rc;
1446         RETURN(rc);
1447 }
1448
1449 int target_handle_disconnect(struct ptlrpc_request *req)
1450 {
1451         int rc;
1452         ENTRY;
1453
1454         rc = req_capsule_server_pack(&req->rq_pill);
1455         if (rc)
1456                 RETURN(rc);
1457
1458         /* Keep the rq_export around so we can send the reply. */
1459         req->rq_status = obd_disconnect(class_export_get(req->rq_export));
1460
1461         RETURN(0);
1462 }
1463
1464 void target_destroy_export(struct obd_export *exp)
1465 {
1466         struct obd_import       *imp = NULL;
1467         /* exports created from last_rcvd data, and "fake"
1468            exports created by lctl don't have an import */
1469         spin_lock(&exp->exp_lock);
1470         if (exp->exp_imp_reverse != NULL) {
1471                 imp = exp->exp_imp_reverse;
1472                 exp->exp_imp_reverse = NULL;
1473         }
1474         spin_unlock(&exp->exp_lock);
1475         if (imp != NULL)
1476                 client_destroy_import(imp);
1477
1478         LASSERT_ATOMIC_ZERO(&exp->exp_locks_count);
1479         LASSERT_ATOMIC_ZERO(&exp->exp_rpc_count);
1480         LASSERT_ATOMIC_ZERO(&exp->exp_cb_count);
1481         LASSERT_ATOMIC_ZERO(&exp->exp_replay_count);
1482 }
1483 EXPORT_SYMBOL(target_destroy_export);
1484
1485 /*
1486  * Recovery functions
1487  */
1488 static void target_request_copy_get(struct ptlrpc_request *req)
1489 {
1490         class_export_rpc_inc(req->rq_export);
1491         LASSERT(list_empty(&req->rq_list));
1492         INIT_LIST_HEAD(&req->rq_replay_list);
1493
1494         /* Increase refcount to keep request in queue. */
1495         atomic_inc(&req->rq_refcount);
1496         /* Let export know it has replays to be handled. */
1497         atomic_inc(&req->rq_export->exp_replay_count);
1498 }
1499
1500 static void target_request_copy_put(struct ptlrpc_request *req)
1501 {
1502         LASSERT(list_empty(&req->rq_replay_list));
1503         LASSERT_ATOMIC_POS(&req->rq_export->exp_replay_count);
1504
1505         atomic_dec(&req->rq_export->exp_replay_count);
1506         class_export_rpc_dec(req->rq_export);
1507         ptlrpc_server_drop_request(req);
1508 }
1509
1510 static int target_exp_enqueue_req_replay(struct ptlrpc_request *req)
1511 {
1512         __u64                  transno = lustre_msg_get_transno(req->rq_reqmsg);
1513         struct obd_export     *exp = req->rq_export;
1514         struct ptlrpc_request *reqiter;
1515         struct ptlrpc_request *dup_req = NULL;
1516         int                    dup = 0;
1517
1518         LASSERT(exp);
1519
1520         spin_lock(&exp->exp_lock);
1521         list_for_each_entry(reqiter, &exp->exp_req_replay_queue,
1522                                 rq_replay_list) {
1523                 if (lustre_msg_get_transno(reqiter->rq_reqmsg) == transno) {
1524                         dup_req = reqiter;
1525                         dup = 1;
1526                         break;
1527                 }
1528         }
1529
1530         if (dup) {
1531                 /* We expect it with RESENT and REPLAY flags. */
1532                 if ((lustre_msg_get_flags(req->rq_reqmsg) &
1533                      (MSG_RESENT | MSG_REPLAY)) != (MSG_RESENT | MSG_REPLAY))
1534                         CERROR("invalid flags %x of resent replay\n",
1535                                lustre_msg_get_flags(req->rq_reqmsg));
1536
1537                 if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY) {
1538                         __u32 new_conn;
1539
1540                         new_conn = lustre_msg_get_conn_cnt(req->rq_reqmsg);
1541                         if (new_conn >
1542                             lustre_msg_get_conn_cnt(dup_req->rq_reqmsg))
1543                                 lustre_msg_set_conn_cnt(dup_req->rq_reqmsg,
1544                                                         new_conn);
1545                 }
1546         } else {
1547                 list_add_tail(&req->rq_replay_list,
1548                                   &exp->exp_req_replay_queue);
1549         }
1550
1551         spin_unlock(&exp->exp_lock);
1552         return dup;
1553 }
1554
1555 static void target_exp_dequeue_req_replay(struct ptlrpc_request *req)
1556 {
1557         LASSERT(!list_empty(&req->rq_replay_list));
1558         LASSERT(req->rq_export);
1559
1560         spin_lock(&req->rq_export->exp_lock);
1561         list_del_init(&req->rq_replay_list);
1562         spin_unlock(&req->rq_export->exp_lock);
1563 }
1564
1565 static void target_finish_recovery(struct lu_target *lut)
1566 {
1567         struct obd_device *obd = lut->lut_obd;
1568         ENTRY;
1569
1570         /* Only log a recovery message when recovery has occurred. */
1571         if (obd->obd_recovery_start) {
1572                 time64_t now = ktime_get_real_seconds();
1573                 time64_t elapsed_time;
1574
1575                 elapsed_time = max_t(time64_t, now - obd->obd_recovery_start, 1);
1576                 LCONSOLE_INFO("%s: Recovery over after %lld:%.02lld, of %d clients "
1577                         "%d recovered and %d %s evicted.\n", obd->obd_name,
1578                         (s64)elapsed_time / 60, (s64)elapsed_time % 60,
1579                         obd->obd_max_recoverable_clients,
1580                         atomic_read(&obd->obd_connected_clients),
1581                         obd->obd_stale_clients,
1582                         obd->obd_stale_clients == 1 ? "was" : "were");
1583         }
1584
1585         ldlm_reprocess_recovery_done(obd->obd_namespace);
1586         spin_lock(&obd->obd_recovery_task_lock);
1587         if (!list_empty(&obd->obd_req_replay_queue) ||
1588             !list_empty(&obd->obd_lock_replay_queue) ||
1589             !list_empty(&obd->obd_final_req_queue)) {
1590                 CERROR("%s: Recovery queues ( %s%s%s) are not empty\n",
1591                        obd->obd_name,
1592                        list_empty(&obd->obd_req_replay_queue) ? "" : "req ",
1593                        list_empty(&obd->obd_lock_replay_queue) ? \
1594                                "" : "lock ",
1595                        list_empty(&obd->obd_final_req_queue) ? \
1596                                "" : "final ");
1597                 spin_unlock(&obd->obd_recovery_task_lock);
1598                 LBUG();
1599         }
1600         spin_unlock(&obd->obd_recovery_task_lock);
1601
1602         obd->obd_recovery_end = ktime_get_real_seconds();
1603
1604         /* When recovery finished, cleanup orphans on MDS and OST. */
1605         if (obd->obd_type && OBP(obd, postrecov)) {
1606                 int rc = OBP(obd, postrecov)(obd);
1607
1608                 if (rc < 0)
1609                         LCONSOLE_WARN("%s: Post recovery failed, rc %d\n",
1610                                       obd->obd_name, rc);
1611         }
1612         EXIT;
1613 }
1614
1615 static void abort_req_replay_queue(struct obd_device *obd)
1616 {
1617         struct ptlrpc_request *req, *n;
1618         struct list_head abort_list;
1619
1620         INIT_LIST_HEAD(&abort_list);
1621         spin_lock(&obd->obd_recovery_task_lock);
1622         list_splice_init(&obd->obd_req_replay_queue, &abort_list);
1623         spin_unlock(&obd->obd_recovery_task_lock);
1624         list_for_each_entry_safe(req, n, &abort_list, rq_list) {
1625                 DEBUG_REQ(D_WARNING, req, "aborted:");
1626                 req->rq_status = -ENOTCONN;
1627                 if (ptlrpc_error(req)) {
1628                         DEBUG_REQ(D_ERROR, req,
1629                                   "failed abort_req_reply; skipping");
1630                 }
1631                 target_exp_dequeue_req_replay(req);
1632                 target_request_copy_put(req);
1633         }
1634 }
1635
1636 static void abort_lock_replay_queue(struct obd_device *obd)
1637 {
1638         struct ptlrpc_request *req, *n;
1639         struct list_head abort_list;
1640
1641         INIT_LIST_HEAD(&abort_list);
1642         spin_lock(&obd->obd_recovery_task_lock);
1643         list_splice_init(&obd->obd_lock_replay_queue, &abort_list);
1644         spin_unlock(&obd->obd_recovery_task_lock);
1645         list_for_each_entry_safe(req, n, &abort_list, rq_list) {
1646                 DEBUG_REQ(D_ERROR, req, "aborted:");
1647                 req->rq_status = -ENOTCONN;
1648                 if (ptlrpc_error(req)) {
1649                         DEBUG_REQ(D_ERROR, req,
1650                                   "failed abort_lock_reply; skipping");
1651                 }
1652                 target_request_copy_put(req);
1653         }
1654 }
1655
1656 /* Called from a cleanup function if the device is being cleaned up
1657    forcefully.  The exports should all have been disconnected already,
1658    the only thing left to do is
1659      - clear the recovery flags
1660      - cancel the timer
1661      - free queued requests and replies, but don't send replies
1662    Because the obd_stopping flag is set, no new requests should be received.
1663
1664 */
1665 void target_cleanup_recovery(struct obd_device *obd)
1666 {
1667         struct ptlrpc_request *req, *n;
1668         struct list_head clean_list;
1669
1670         INIT_LIST_HEAD(&clean_list);
1671         spin_lock(&obd->obd_dev_lock);
1672         if (!obd->obd_recovering) {
1673                 spin_unlock(&obd->obd_dev_lock);
1674                 EXIT;
1675                 return;
1676         }
1677         obd->obd_recovering = obd->obd_abort_recovery = 0;
1678         spin_unlock(&obd->obd_dev_lock);
1679
1680         spin_lock(&obd->obd_recovery_task_lock);
1681         target_cancel_recovery_timer(obd);
1682         list_splice_init(&obd->obd_req_replay_queue, &clean_list);
1683         spin_unlock(&obd->obd_recovery_task_lock);
1684
1685         list_for_each_entry_safe(req, n, &clean_list, rq_list) {
1686                 LASSERT(req->rq_reply_state == NULL);
1687                 target_exp_dequeue_req_replay(req);
1688                 target_request_copy_put(req);
1689         }
1690
1691         spin_lock(&obd->obd_recovery_task_lock);
1692         list_splice_init(&obd->obd_lock_replay_queue, &clean_list);
1693         list_splice_init(&obd->obd_final_req_queue, &clean_list);
1694         spin_unlock(&obd->obd_recovery_task_lock);
1695
1696         list_for_each_entry_safe(req, n, &clean_list, rq_list) {
1697                 LASSERT(req->rq_reply_state == NULL);
1698                 target_request_copy_put(req);
1699         }
1700
1701         EXIT;
1702 }
1703 EXPORT_SYMBOL(target_cleanup_recovery);
1704
1705 /* obd_recovery_task_lock should be held */
1706 void target_cancel_recovery_timer(struct obd_device *obd)
1707 {
1708         CDEBUG(D_HA, "%s: cancel recovery timer\n", obd->obd_name);
1709         hrtimer_cancel(&obd->obd_recovery_timer);
1710 }
1711
1712 static void target_start_recovery_timer(struct obd_device *obd)
1713 {
1714         ktime_t delay;
1715
1716         if (obd->obd_recovery_start != 0)
1717                 return;
1718
1719         spin_lock(&obd->obd_dev_lock);
1720         if (!obd->obd_recovering || obd->obd_abort_recovery) {
1721                 spin_unlock(&obd->obd_dev_lock);
1722                 return;
1723         }
1724
1725         LASSERT(obd->obd_recovery_timeout != 0);
1726
1727         if (obd->obd_recovery_start != 0) {
1728                 spin_unlock(&obd->obd_dev_lock);
1729                 return;
1730         }
1731
1732         delay = ktime_set(obd->obd_recovery_timeout, 0);
1733         hrtimer_start(&obd->obd_recovery_timer, delay, HRTIMER_MODE_REL);
1734         obd->obd_recovery_start = ktime_get_real_seconds();
1735         spin_unlock(&obd->obd_dev_lock);
1736
1737         LCONSOLE_WARN("%s: Will be in recovery for at least %llu:%02llu, or until %d client%s reconnect%s\n",
1738                       obd->obd_name,
1739                       obd->obd_recovery_timeout / 60,
1740                       obd->obd_recovery_timeout % 60,
1741                       obd->obd_max_recoverable_clients,
1742                       (obd->obd_max_recoverable_clients == 1) ? "" : "s",
1743                       (obd->obd_max_recoverable_clients == 1) ? "s": "");
1744 }
1745
1746 /**
1747  * extend recovery window.
1748  *
1749  * if @extend is true, extend recovery window to have @drt remaining at least;
1750  * otherwise, make sure the recovery timeout value is not less than @drt.
1751  */
1752 static void extend_recovery_timer(struct obd_device *obd, time_t drt,
1753                                   bool extend)
1754 {
1755         ktime_t left_ns;
1756         time_t left;
1757         time_t to;
1758
1759         spin_lock(&obd->obd_dev_lock);
1760         if (!obd->obd_recovering || obd->obd_abort_recovery) {
1761                 spin_unlock(&obd->obd_dev_lock);
1762                 return;
1763         }
1764         LASSERT(obd->obd_recovery_start != 0);
1765
1766         to = obd->obd_recovery_timeout;
1767         left_ns = hrtimer_expires_remaining(&obd->obd_recovery_timer);
1768         left = ktime_divns(left_ns, NSEC_PER_SEC);
1769         if (extend && (drt > left))
1770                 to += drt - left;
1771         else if (!extend && (drt > to))
1772                 to = drt;
1773
1774         if (to > obd->obd_recovery_time_hard) {
1775                 to = obd->obd_recovery_time_hard;
1776                 CWARN("%s: extended recovery timer reaching hard limit: %ld, extend: %d\n",
1777                       obd->obd_name, to, extend);
1778         }
1779
1780         if (obd->obd_recovery_timeout < to) {
1781                 ktime_t now = ktime_get_real();
1782                 ktime_t end;
1783
1784                 obd->obd_recovery_timeout = to;
1785                 end = ktime_set(obd->obd_recovery_start + to, 0);
1786                 left_ns = ktime_sub(end, now);
1787                 hrtimer_forward_now(&obd->obd_recovery_timer, left_ns);
1788                 left = ktime_divns(left_ns, NSEC_PER_MSEC);
1789         }
1790         spin_unlock(&obd->obd_dev_lock);
1791
1792         CDEBUG(D_HA, "%s: recovery timer will expire in %ld seconds\n",
1793                 obd->obd_name, left);
1794 }
1795
1796 /* Reset the timer with each new client connection */
1797 /*
1798  * This timer is actually reconnect_timer, which is for making sure
1799  * the total recovery window is at least as big as my reconnect
1800  * attempt timing. So the initial recovery time_out will be set to
1801  * OBD_RECOVERY_FACTOR * obd_timeout. If the timeout coming
1802  * from client is bigger than this, then the recovery time_out will
1803  * be extended to make sure the client could be reconnected, in the
1804  * process, the timeout from the new client should be ignored.
1805  */
1806 static void
1807 check_and_start_recovery_timer(struct obd_device *obd,
1808                                struct ptlrpc_request *req,
1809                                int new_client)
1810 {
1811         time_t service_time = lustre_msg_get_service_time(req->rq_reqmsg);
1812         struct obd_device_target *obt = &obd->u.obt;
1813
1814         if (!new_client && service_time)
1815                 /* Teach server about old server's estimates, as first guess
1816                  * at how long new requests will take.
1817                  */
1818                 at_measured(&req->rq_rqbd->rqbd_svcpt->scp_at_estimate,
1819                             service_time);
1820
1821         target_start_recovery_timer(obd);
1822
1823         /* Convert the service time to RPC timeout,
1824          * and reuse service_time to limit stack usage.
1825          */
1826         service_time = at_est2timeout(service_time);
1827
1828         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_SLUGGISH_NET) &&
1829             service_time < at_extra)
1830                 service_time = at_extra;
1831
1832         /* We expect other clients to timeout within service_time, then try
1833          * to reconnect, then try the failover server.  The max delay between
1834          * connect attempts is SWITCH_MAX + SWITCH_INC + INITIAL. */
1835         service_time += 2 * INITIAL_CONNECT_TIMEOUT;
1836
1837         LASSERT(obt->obt_magic == OBT_MAGIC);
1838         service_time += 2 * (CONNECTION_SWITCH_MAX + CONNECTION_SWITCH_INC);
1839         if (service_time > obd->obd_recovery_timeout && !new_client)
1840                 extend_recovery_timer(obd, service_time, false);
1841 }
1842
1843 /** Health checking routines */
1844 static inline int exp_connect_healthy(struct obd_export *exp)
1845 {
1846         return (exp->exp_in_recovery);
1847 }
1848
1849 /** if export done req_replay or has replay in queue */
1850 static inline int exp_req_replay_healthy(struct obd_export *exp)
1851 {
1852         return (!exp->exp_req_replay_needed ||
1853                 atomic_read(&exp->exp_replay_count) > 0);
1854 }
1855
1856
1857 static inline int exp_req_replay_healthy_or_from_mdt(struct obd_export *exp)
1858 {
1859         return (exp_connect_flags(exp) & OBD_CONNECT_MDS_MDS) ||
1860                exp_req_replay_healthy(exp);
1861 }
1862
1863 /** if export done lock_replay or has replay in queue */
1864 static inline int exp_lock_replay_healthy(struct obd_export *exp)
1865 {
1866         return (!exp->exp_lock_replay_needed ||
1867                 atomic_read(&exp->exp_replay_count) > 0);
1868 }
1869
1870 static inline int exp_vbr_healthy(struct obd_export *exp)
1871 {
1872         return (!exp->exp_vbr_failed);
1873 }
1874
1875 static inline int exp_finished(struct obd_export *exp)
1876 {
1877         return (exp->exp_in_recovery && !exp->exp_lock_replay_needed);
1878 }
1879
1880 static inline int exp_finished_or_from_mdt(struct obd_export *exp)
1881 {
1882         return (exp_connect_flags(exp) & OBD_CONNECT_MDS_MDS) ||
1883                 exp_finished(exp);
1884 }
1885
1886 static int check_for_next_transno(struct lu_target *lut)
1887 {
1888         struct ptlrpc_request *req = NULL;
1889         struct obd_device *obd = lut->lut_obd;
1890         struct target_distribute_txn_data *tdtd = lut->lut_tdtd;
1891         int wake_up = 0, connected, completed, queue_len;
1892         __u64 req_transno = 0;
1893         __u64 update_transno = 0;
1894         __u64 next_transno = 0;
1895         ENTRY;
1896
1897         spin_lock(&obd->obd_recovery_task_lock);
1898         if (!list_empty(&obd->obd_req_replay_queue)) {
1899                 req = list_entry(obd->obd_req_replay_queue.next,
1900                                      struct ptlrpc_request, rq_list);
1901                 req_transno = lustre_msg_get_transno(req->rq_reqmsg);
1902         }
1903
1904         if (tdtd != NULL)
1905                 update_transno = distribute_txn_get_next_transno(tdtd);
1906
1907         connected = atomic_read(&obd->obd_connected_clients);
1908         completed = connected - atomic_read(&obd->obd_req_replay_clients);
1909         queue_len = obd->obd_requests_queued_for_recovery;
1910         next_transno = obd->obd_next_recovery_transno;
1911
1912         CDEBUG(D_HA, "max: %d, connected: %d, completed: %d, queue_len: %d, "
1913                "req_transno: %llu, next_transno: %llu\n",
1914                obd->obd_max_recoverable_clients, connected, completed,
1915                queue_len, req_transno, next_transno);
1916
1917         if (obd->obd_abort_recovery) {
1918                 CDEBUG(D_HA, "waking for aborted recovery\n");
1919                 wake_up = 1;
1920         } else if (obd->obd_recovery_expired) {
1921                 CDEBUG(D_HA, "waking for expired recovery\n");
1922                 wake_up = 1;
1923         } else if (tdtd != NULL && req != NULL &&
1924                    is_req_replayed_by_update(req)) {
1925                 LASSERTF(req_transno < next_transno, "req_transno %llu"
1926                          "next_transno%llu\n", req_transno, next_transno);
1927                 CDEBUG(D_HA, "waking for duplicate req (%llu)\n",
1928                        req_transno);
1929                 wake_up = 1;
1930         } else if (req_transno == next_transno ||
1931                    (update_transno != 0 && update_transno <= next_transno)) {
1932                 CDEBUG(D_HA, "waking for next (%lld)\n", next_transno);
1933                 wake_up = 1;
1934         } else if (queue_len > 0 &&
1935                    queue_len == atomic_read(&obd->obd_req_replay_clients)) {
1936                 /** handle gaps occured due to lost reply or VBR */
1937                 LASSERTF(req_transno >= next_transno,
1938                          "req_transno: %llu, next_transno: %llu\n",
1939                          req_transno, next_transno);
1940                 CDEBUG(D_HA,
1941                        "%s: waking for gap in transno, VBR is %s (skip: "
1942                        "%lld, ql: %d, comp: %d, conn: %d, next: %lld"
1943                        ", next_update %lld last_committed: %lld)\n",
1944                        obd->obd_name, obd->obd_version_recov ? "ON" : "OFF",
1945                        next_transno, queue_len, completed, connected,
1946                        req_transno, update_transno, obd->obd_last_committed);
1947                 obd->obd_next_recovery_transno = req_transno;
1948                 wake_up = 1;
1949         } else if (atomic_read(&obd->obd_req_replay_clients) == 0) {
1950                 CDEBUG(D_HA, "waking for completed recovery\n");
1951                 wake_up = 1;
1952         } else if (OBD_FAIL_CHECK(OBD_FAIL_MDS_RECOVERY_ACCEPTS_GAPS)) {
1953                 CDEBUG(D_HA, "accepting transno gaps is explicitly allowed"
1954                        " by fail_lock, waking up (%lld)\n", next_transno);
1955                 obd->obd_next_recovery_transno = req_transno;
1956                 wake_up = 1;
1957         }
1958         spin_unlock(&obd->obd_recovery_task_lock);
1959         return wake_up;
1960 }
1961
1962 static int check_for_next_lock(struct lu_target *lut)
1963 {
1964         struct obd_device *obd = lut->lut_obd;
1965         int wake_up = 0;
1966
1967         spin_lock(&obd->obd_recovery_task_lock);
1968         if (!list_empty(&obd->obd_lock_replay_queue)) {
1969                 CDEBUG(D_HA, "waking for next lock\n");
1970                 wake_up = 1;
1971         } else if (atomic_read(&obd->obd_lock_replay_clients) == 0) {
1972                 CDEBUG(D_HA, "waking for completed lock replay\n");
1973                 wake_up = 1;
1974         } else if (obd->obd_abort_recovery) {
1975                 CDEBUG(D_HA, "waking for aborted recovery\n");
1976                 wake_up = 1;
1977         } else if (obd->obd_recovery_expired) {
1978                 CDEBUG(D_HA, "waking for expired recovery\n");
1979                 wake_up = 1;
1980         }
1981         spin_unlock(&obd->obd_recovery_task_lock);
1982
1983         return wake_up;
1984 }
1985
1986 /**
1987  * wait for recovery events,
1988  * check its status with help of check_routine
1989  * evict dead clients via health_check
1990  */
1991 static int target_recovery_overseer(struct lu_target *lut,
1992                                     int (*check_routine)(struct lu_target *),
1993                                     int (*health_check)(struct obd_export *))
1994 {
1995         struct obd_device       *obd = lut->lut_obd;
1996         struct target_distribute_txn_data *tdtd;
1997         time64_t last = 0;
1998         time64_t now;
1999 repeat:
2000         if (obd->obd_recovering && obd->obd_recovery_start == 0) {
2001                 now = ktime_get_seconds();
2002                 if (now - last > 600) {
2003                         LCONSOLE_INFO("%s: in recovery but waiting for "
2004                                       "the first client to connect\n",
2005                                       obd->obd_name);
2006                         last = now;
2007                 }
2008         }
2009         if (obd->obd_recovery_start != 0 && ktime_get_real_seconds() >=
2010               (obd->obd_recovery_start + obd->obd_recovery_time_hard)) {
2011                 __u64 next_update_transno = 0;
2012
2013                 /* Only abort the recovery if there are no update recovery
2014                  * left in the queue */
2015                 spin_lock(&obd->obd_recovery_task_lock);
2016                 if (lut->lut_tdtd != NULL) {
2017                         next_update_transno =
2018                                 distribute_txn_get_next_transno(lut->lut_tdtd);
2019
2020                         tdtd = lut->lut_tdtd;
2021                         /* If next_update_transno == 0, it probably because
2022                          * updatelog retrieve threads did not get any records
2023                          * yet, let's wait those threads stopped */
2024                         if (next_update_transno == 0) {
2025                                 struct l_wait_info lwi = { 0 };
2026
2027                                 l_wait_event(tdtd->tdtd_recovery_threads_waitq,
2028                                        atomic_read(
2029                                        &tdtd->tdtd_recovery_threads_count) == 0,
2030                                        &lwi);
2031
2032                                 next_update_transno =
2033                                         distribute_txn_get_next_transno(
2034                                                                 lut->lut_tdtd);
2035                         }
2036                 }
2037
2038                 if (next_update_transno != 0 && !obd->obd_abort_recovery) {
2039                         obd->obd_next_recovery_transno = next_update_transno;
2040                         spin_unlock(&obd->obd_recovery_task_lock);
2041                         /* Disconnect unfinished exports from clients, and
2042                          * keep connection from MDT to make sure the update
2043                          * recovery will still keep trying until some one
2044                          * manually abort the recovery */
2045                         class_disconnect_stale_exports(obd,
2046                                                 exp_finished_or_from_mdt);
2047                         /* Abort all of replay and replay lock req from
2048                          * clients */
2049                         abort_req_replay_queue(obd);
2050                         abort_lock_replay_queue(obd);
2051                         CDEBUG(D_HA, "%s: there are still update replay (%#llx"
2052                                ")in the queue.\n", obd->obd_name,
2053                                next_update_transno);
2054                 } else {
2055                         obd->obd_abort_recovery = 1;
2056                         spin_unlock(&obd->obd_recovery_task_lock);
2057                         CWARN("%s recovery is aborted by hard timeout\n",
2058                               obd->obd_name);
2059                 }
2060         }
2061
2062         while (wait_event_timeout(obd->obd_next_transno_waitq,
2063                                   check_routine(lut),
2064                                   msecs_to_jiffies(60 * MSEC_PER_SEC)) == 0)
2065                 /* wait indefinitely for event, but don't trigger watchdog */;
2066
2067         if (obd->obd_abort_recovery) {
2068                 CWARN("recovery is aborted, evict exports in recovery\n");
2069                 if (lut->lut_tdtd != NULL) {
2070                         struct l_wait_info lwi = { 0 };
2071
2072                         tdtd = lut->lut_tdtd;
2073                         /* Let's wait all of the update log recovery thread
2074                          * finished */
2075                         l_wait_event(tdtd->tdtd_recovery_threads_waitq,
2076                          atomic_read(&tdtd->tdtd_recovery_threads_count) == 0,
2077                              &lwi);
2078                         /* Then abort the update recovery list */
2079                         dtrq_list_destroy(lut->lut_tdtd);
2080                 }
2081
2082                 /** evict exports which didn't finish recovery yet */
2083                 class_disconnect_stale_exports(obd, exp_finished);
2084                 return 1;
2085         } else if (obd->obd_recovery_expired) {
2086                 obd->obd_recovery_expired = 0;
2087                 /** If some clients died being recovered, evict them */
2088                 LCONSOLE_WARN("%s: recovery is timed out, "
2089                               "evict stale exports\n", obd->obd_name);
2090                 /** evict cexports with no replay in queue, they are stalled */
2091                 class_disconnect_stale_exports(obd, health_check);
2092
2093                 /** continue with VBR */
2094                 spin_lock(&obd->obd_dev_lock);
2095                 obd->obd_version_recov = 1;
2096                 spin_unlock(&obd->obd_dev_lock);
2097                 /**
2098                  * reset timer, recovery will proceed with versions now,
2099                  * timeout is set just to handle reconnection delays
2100                  */
2101                 extend_recovery_timer(obd, RECONNECT_DELAY_MAX, true);
2102                 /** Wait for recovery events again, after evicting bad clients */
2103                 goto repeat;
2104         }
2105         return 0;
2106 }
2107
2108 static struct ptlrpc_request *target_next_replay_lock(struct lu_target *lut)
2109 {
2110         struct obd_device       *obd = lut->lut_obd;
2111         struct ptlrpc_request *req = NULL;
2112
2113         CDEBUG(D_HA, "Waiting for lock\n");
2114         if (target_recovery_overseer(lut, check_for_next_lock,
2115                                      exp_lock_replay_healthy))
2116                 abort_lock_replay_queue(obd);
2117
2118         spin_lock(&obd->obd_recovery_task_lock);
2119         if (!list_empty(&obd->obd_lock_replay_queue)) {
2120                 req = list_entry(obd->obd_lock_replay_queue.next,
2121                                      struct ptlrpc_request, rq_list);
2122                 list_del_init(&req->rq_list);
2123                 spin_unlock(&obd->obd_recovery_task_lock);
2124         } else {
2125                 spin_unlock(&obd->obd_recovery_task_lock);
2126                 LASSERT(list_empty(&obd->obd_lock_replay_queue));
2127                 LASSERT(atomic_read(&obd->obd_lock_replay_clients) == 0);
2128                 /** evict exports failed VBR */
2129                 class_disconnect_stale_exports(obd, exp_vbr_healthy);
2130         }
2131         return req;
2132 }
2133
2134 static struct ptlrpc_request *target_next_final_ping(struct obd_device *obd)
2135 {
2136         struct ptlrpc_request *req = NULL;
2137
2138         spin_lock(&obd->obd_recovery_task_lock);
2139         if (!list_empty(&obd->obd_final_req_queue)) {
2140                 req = list_entry(obd->obd_final_req_queue.next,
2141                                      struct ptlrpc_request, rq_list);
2142                 list_del_init(&req->rq_list);
2143                 spin_unlock(&obd->obd_recovery_task_lock);
2144                 if (req->rq_export->exp_in_recovery) {
2145                         spin_lock(&req->rq_export->exp_lock);
2146                         req->rq_export->exp_in_recovery = 0;
2147                         spin_unlock(&req->rq_export->exp_lock);
2148                 }
2149         } else {
2150                 spin_unlock(&obd->obd_recovery_task_lock);
2151         }
2152         return req;
2153 }
2154
2155 static void handle_recovery_req(struct ptlrpc_thread *thread,
2156                                 struct ptlrpc_request *req,
2157                                 svc_handler_t handler)
2158 {
2159         ENTRY;
2160
2161         /**
2162          * export can be evicted during recovery, no need to handle replays for
2163          * it after that, discard such request silently
2164          */
2165         if (req->rq_export->exp_disconnected)
2166                 RETURN_EXIT;
2167
2168         req->rq_session.lc_thread = thread;
2169         req->rq_svc_thread = thread;
2170         req->rq_svc_thread->t_env->le_ses = &req->rq_session;
2171
2172         /* thread context */
2173         lu_context_enter(&thread->t_env->le_ctx);
2174         (void)handler(req);
2175         lu_context_exit(&thread->t_env->le_ctx);
2176
2177         /* don't reset timer for final stage */
2178         if (!exp_finished(req->rq_export)) {
2179                 time_t to = obd_timeout;
2180
2181                 /**
2182                  * Add request timeout to the recovery time so next request from
2183                  * this client may come in recovery time
2184                  */
2185                 if (!AT_OFF) {
2186                         struct ptlrpc_service_part *svcpt;
2187
2188                         svcpt = req->rq_rqbd->rqbd_svcpt;
2189                         /* If the server sent early reply for this request,
2190                          * the client will recalculate the timeout according to
2191                          * current server estimate service time, so we will
2192                          * use the maxium timeout here for waiting the client
2193                          * sending the next req
2194                          */
2195                         to = max_t(time_t, at_est2timeout(at_get(&svcpt->scp_at_estimate)),
2196                                    lustre_msg_get_timeout(req->rq_reqmsg));
2197                         /* Add 2 net_latency, one for balance rq_deadline
2198                          * (see ptl_send_rpc), one for resend the req to server,
2199                          * Note: client will pack net_latency in replay req
2200                          * (see ptlrpc_replay_req) */
2201                         to += 2 * lustre_msg_get_service_time(req->rq_reqmsg);
2202                 }
2203                 extend_recovery_timer(class_exp2obd(req->rq_export), to, true);
2204         }
2205         EXIT;
2206 }
2207
2208 /** Checking routines for recovery */
2209 static int check_for_recovery_ready(struct lu_target *lut)
2210 {
2211         struct obd_device *obd = lut->lut_obd;
2212         unsigned int clnts = atomic_read(&obd->obd_connected_clients);
2213
2214         CDEBUG(D_HA, "connected %d stale %d max_recoverable_clients %d"
2215                " abort %d expired %d\n", clnts, obd->obd_stale_clients,
2216                obd->obd_max_recoverable_clients, obd->obd_abort_recovery,
2217                obd->obd_recovery_expired);
2218
2219         if (!obd->obd_abort_recovery && !obd->obd_recovery_expired) {
2220                 LASSERT(clnts <= obd->obd_max_recoverable_clients);
2221                 if (clnts + obd->obd_stale_clients <
2222                     obd->obd_max_recoverable_clients)
2223                         return 0;
2224         }
2225
2226         if (lut->lut_tdtd != NULL) {
2227                 if (!lut->lut_tdtd->tdtd_replay_ready &&
2228                     !obd->obd_abort_recovery) {
2229                         /* Let's extend recovery timer, in case the recovery
2230                          * timer expired, and some clients got evicted */
2231                         extend_recovery_timer(obd, obd->obd_recovery_timeout,
2232                                               true);
2233                         CDEBUG(D_HA, "%s update recovery is not ready, extend recovery %llu\n",
2234                                obd->obd_name, obd->obd_recovery_timeout);
2235                         return 0;
2236                 }
2237         }
2238
2239         return 1;
2240 }
2241
2242 enum {
2243         REQUEST_RECOVERY = 1,
2244         UPDATE_RECOVERY = 2,
2245 };
2246
2247 static __u64 get_next_replay_req_transno(struct obd_device *obd)
2248 {
2249         __u64 transno = 0;
2250
2251         if (!list_empty(&obd->obd_req_replay_queue)) {
2252                 struct ptlrpc_request *req;
2253
2254                 req = list_entry(obd->obd_req_replay_queue.next,
2255                                  struct ptlrpc_request, rq_list);
2256                 transno = lustre_msg_get_transno(req->rq_reqmsg);
2257         }
2258
2259         return transno;
2260 }
2261
2262 static __u64 get_next_transno(struct lu_target *lut, int *type)
2263 {
2264         struct obd_device *obd = lut->lut_obd;
2265         struct target_distribute_txn_data *tdtd = lut->lut_tdtd;
2266         __u64 transno = 0;
2267         __u64 update_transno;
2268         ENTRY;
2269
2270         transno = get_next_replay_req_transno(obd);
2271         if (type != NULL)
2272                 *type = REQUEST_RECOVERY;
2273
2274         if (tdtd == NULL)
2275                 RETURN(transno);
2276
2277         update_transno = distribute_txn_get_next_transno(tdtd);
2278         if (transno == 0 || (transno >= update_transno &&
2279                              update_transno != 0)) {
2280                 transno = update_transno;
2281                 if (type != NULL)
2282                         *type = UPDATE_RECOVERY;
2283         }
2284
2285         RETURN(transno);
2286 }
2287
2288 /**
2289  * drop duplicate replay request
2290  *
2291  * Because the operation has been replayed by update recovery, the request
2292  * with the same transno will be dropped and also notify the client to send
2293  * next replay request.
2294  *
2295  * \param[in] env       execution environment
2296  * \param[in] obd       failover obd device
2297  * \param[in] req       request to be dropped
2298  */
2299 static void drop_duplicate_replay_req(struct lu_env *env,
2300                                       struct obd_device *obd,
2301                                       struct ptlrpc_request *req)
2302 {
2303         DEBUG_REQ(D_HA, req, "remove t%lld from %s because of duplicate"
2304                   " update records are found.\n",
2305                   lustre_msg_get_transno(req->rq_reqmsg),
2306                   libcfs_nid2str(req->rq_peer.nid));
2307
2308         /* Right now, only for MDS reint operation update replay and
2309          * normal request replay can have the same transno */
2310         if (lustre_msg_get_opc(req->rq_reqmsg) == MDS_REINT) {
2311                 req_capsule_set(&req->rq_pill, &RQF_MDS_REINT);
2312                 req->rq_status = req_capsule_server_pack(&req->rq_pill);
2313                 if (likely(req->rq_export))
2314                         target_committed_to_req(req);
2315                 lustre_msg_set_transno(req->rq_repmsg, req->rq_transno);
2316                 target_send_reply(req, req->rq_status, 0);
2317         } else {
2318                 DEBUG_REQ(D_ERROR, req, "wrong opc" "from %s\n",
2319                 libcfs_nid2str(req->rq_peer.nid));
2320         }
2321         target_exp_dequeue_req_replay(req);
2322         target_request_copy_put(req);
2323         obd->obd_replayed_requests++;
2324 }
2325
2326 static void replay_request_or_update(struct lu_env *env,
2327                                      struct lu_target *lut,
2328                                      struct target_recovery_data *trd,
2329                                      struct ptlrpc_thread *thread)
2330 {
2331         struct obd_device *obd = lut->lut_obd;
2332         struct ptlrpc_request *req = NULL;
2333         int                     type;
2334         __u64                   transno;
2335         ENTRY;
2336
2337         CDEBUG(D_HA, "Waiting for transno %lld\n",
2338                obd->obd_next_recovery_transno);
2339
2340         /* Replay all of request and update by transno */
2341         do {
2342                 struct target_distribute_txn_data *tdtd = lut->lut_tdtd;
2343
2344                 CFS_FAIL_TIMEOUT(OBD_FAIL_TGT_REPLAY_DELAY2, cfs_fail_val);
2345
2346                 /** It is needed to extend recovery window above
2347                  *  recovery_time_soft. Extending is possible only in the
2348                  *  end of recovery window (see more details in
2349                  *  handle_recovery_req()).
2350                  */
2351                 CFS_FAIL_TIMEOUT_MS(OBD_FAIL_TGT_REPLAY_DELAY, 300);
2352
2353                 if (target_recovery_overseer(lut, check_for_next_transno,
2354                                         exp_req_replay_healthy_or_from_mdt)) {
2355                         abort_req_replay_queue(obd);
2356                         abort_lock_replay_queue(obd);
2357                         goto abort;
2358                 }
2359
2360                 spin_lock(&obd->obd_recovery_task_lock);
2361                 transno = get_next_transno(lut, &type);
2362                 if (type == REQUEST_RECOVERY && transno != 0) {
2363                         /* Drop replay request from client side, if the
2364                          * replay has been executed by update with the
2365                          * same transno */
2366                         req = list_entry(obd->obd_req_replay_queue.next,
2367                                         struct ptlrpc_request, rq_list);
2368
2369                         list_del_init(&req->rq_list);
2370                         obd->obd_requests_queued_for_recovery--;
2371                         spin_unlock(&obd->obd_recovery_task_lock);
2372
2373                         /* Let's check if the request has been redone by
2374                          * update replay */
2375                         if (is_req_replayed_by_update(req)) {
2376                                 struct distribute_txn_replay_req *dtrq;
2377
2378                                 dtrq = distribute_txn_lookup_finish_list(tdtd,
2379                                                                    req->rq_xid);
2380                                 LASSERT(dtrq != NULL);
2381                                 spin_lock(&tdtd->tdtd_replay_list_lock);
2382                                 list_del_init(&dtrq->dtrq_list);
2383                                 spin_unlock(&tdtd->tdtd_replay_list_lock);
2384                                 dtrq_destroy(dtrq);
2385
2386                                 drop_duplicate_replay_req(env, obd, req);
2387
2388                                 continue;
2389                         }
2390
2391                         LASSERT(trd->trd_processing_task == current_pid());
2392                         DEBUG_REQ(D_HA, req, "processing t%lld from %s",
2393                                   lustre_msg_get_transno(req->rq_reqmsg),
2394                                   libcfs_nid2str(req->rq_peer.nid));
2395
2396                         handle_recovery_req(thread, req,
2397                                             trd->trd_recovery_handler);
2398                         /**
2399                          * bz18031: increase next_recovery_transno before
2400                          * target_request_copy_put() will drop exp_rpc reference
2401                          */
2402                         spin_lock(&obd->obd_recovery_task_lock);
2403                         obd->obd_next_recovery_transno++;
2404                         spin_unlock(&obd->obd_recovery_task_lock);
2405                         target_exp_dequeue_req_replay(req);
2406                         target_request_copy_put(req);
2407                         obd->obd_replayed_requests++;
2408                 } else if (type == UPDATE_RECOVERY && transno != 0) {
2409                         struct distribute_txn_replay_req *dtrq;
2410                         int rc;
2411
2412                         spin_unlock(&obd->obd_recovery_task_lock);
2413
2414                         LASSERT(tdtd != NULL);
2415                         dtrq = distribute_txn_get_next_req(tdtd);
2416                         lu_context_enter(&thread->t_env->le_ctx);
2417                         rc = tdtd->tdtd_replay_handler(env, tdtd, dtrq);
2418                         lu_context_exit(&thread->t_env->le_ctx);
2419                         extend_recovery_timer(obd, obd_timeout, true);
2420
2421                         if (rc == 0 && dtrq->dtrq_xid != 0) {
2422                                 CDEBUG(D_HA, "Move x%llu t%llu"
2423                                        " to finish list\n", dtrq->dtrq_xid,
2424                                        dtrq->dtrq_master_transno);
2425
2426                                 /* Add it to the replay finish list */
2427                                 spin_lock(&tdtd->tdtd_replay_list_lock);
2428                                 list_add(&dtrq->dtrq_list,
2429                                          &tdtd->tdtd_replay_finish_list);
2430                                 spin_unlock(&tdtd->tdtd_replay_list_lock);
2431
2432                                 spin_lock(&obd->obd_recovery_task_lock);
2433                                 if (transno == obd->obd_next_recovery_transno)
2434                                         obd->obd_next_recovery_transno++;
2435                                 else if (transno >
2436                                          obd->obd_next_recovery_transno)
2437                                         obd->obd_next_recovery_transno =
2438                                                                 transno + 1;
2439                                 spin_unlock(&obd->obd_recovery_task_lock);
2440                         } else {
2441                                 dtrq_destroy(dtrq);
2442                         }
2443                 } else {
2444                         spin_unlock(&obd->obd_recovery_task_lock);
2445 abort:
2446                         LASSERT(list_empty(&obd->obd_req_replay_queue));
2447                         LASSERT(atomic_read(&obd->obd_req_replay_clients) == 0);
2448                         /** evict exports failed VBR */
2449                         class_disconnect_stale_exports(obd, exp_vbr_healthy);
2450                         break;
2451                 }
2452         } while (1);
2453 }
2454
2455 static int target_recovery_thread(void *arg)
2456 {
2457         struct lu_target *lut = arg;
2458         struct obd_device *obd = lut->lut_obd;
2459         struct ptlrpc_request *req;
2460         struct target_recovery_data *trd = &obd->obd_recovery_data;
2461         unsigned long delta;
2462         struct lu_env *env;
2463         struct ptlrpc_thread *thread = NULL;
2464         int rc = 0;
2465         ENTRY;
2466
2467         unshare_fs_struct();
2468         OBD_ALLOC_PTR(thread);
2469         if (thread == NULL)
2470                 RETURN(-ENOMEM);
2471
2472         OBD_ALLOC_PTR(env);
2473         if (env == NULL) {
2474                 OBD_FREE_PTR(thread);
2475                 RETURN(-ENOMEM);
2476         }
2477
2478         rc = lu_context_init(&env->le_ctx, LCT_MD_THREAD | LCT_DT_THREAD);
2479         if (rc) {
2480                 OBD_FREE_PTR(thread);
2481                 OBD_FREE_PTR(env);
2482                 RETURN(rc);
2483         }
2484
2485         thread->t_env = env;
2486         thread->t_id = -1; /* force filter_iobuf_get/put to use local buffers */
2487         env->le_ctx.lc_thread = thread;
2488         tgt_io_thread_init(thread); /* init thread_big_cache for IO requests */
2489
2490         CDEBUG(D_HA, "%s: started recovery thread pid %d\n", obd->obd_name,
2491                current_pid());
2492         trd->trd_processing_task = current_pid();
2493
2494         spin_lock(&obd->obd_dev_lock);
2495         obd->obd_recovering = 1;
2496         spin_unlock(&obd->obd_dev_lock);
2497         complete(&trd->trd_starting);
2498
2499         /* first of all, we have to know the first transno to replay */
2500         if (target_recovery_overseer(lut, check_for_recovery_ready,
2501                                      exp_connect_healthy)) {
2502                 abort_req_replay_queue(obd);
2503                 abort_lock_replay_queue(obd);
2504                 if (lut->lut_tdtd != NULL)
2505                         dtrq_list_destroy(lut->lut_tdtd);
2506         }
2507
2508         /* next stage: replay requests or update */
2509         delta = jiffies;
2510         CDEBUG(D_INFO, "1: request replay stage - %d clients from t%llu\n",
2511                atomic_read(&obd->obd_req_replay_clients),
2512                obd->obd_next_recovery_transno);
2513         replay_request_or_update(env, lut, trd, thread);
2514
2515         /**
2516          * The second stage: replay locks
2517          */
2518         CDEBUG(D_INFO, "2: lock replay stage - %d clients\n",
2519                atomic_read(&obd->obd_lock_replay_clients));
2520         while ((req = target_next_replay_lock(lut))) {
2521                 LASSERT(trd->trd_processing_task == current_pid());
2522                 DEBUG_REQ(D_HA, req, "processing lock from %s: ",
2523                           libcfs_nid2str(req->rq_peer.nid));
2524                 handle_recovery_req(thread, req,
2525                                     trd->trd_recovery_handler);
2526                 target_request_copy_put(req);
2527                 obd->obd_replayed_locks++;
2528         }
2529
2530         /**
2531          * The third stage: reply on final pings, at this moment all clients
2532          * must have request in final queue
2533          */
2534         CFS_FAIL_TIMEOUT(OBD_FAIL_TGT_REPLAY_RECONNECT, cfs_fail_val);
2535         CDEBUG(D_INFO, "3: final stage - process recovery completion pings\n");
2536         /** Update server last boot epoch */
2537         tgt_boot_epoch_update(lut);
2538         /* We drop recoverying flag to forward all new requests
2539          * to regular mds_handle() since now */
2540         spin_lock(&obd->obd_dev_lock);
2541         obd->obd_recovering = obd->obd_abort_recovery = 0;
2542         spin_unlock(&obd->obd_dev_lock);
2543         spin_lock(&obd->obd_recovery_task_lock);
2544         target_cancel_recovery_timer(obd);
2545         spin_unlock(&obd->obd_recovery_task_lock);
2546         while ((req = target_next_final_ping(obd))) {
2547                 LASSERT(trd->trd_processing_task == current_pid());
2548                 DEBUG_REQ(D_HA, req, "processing final ping from %s: ",
2549                           libcfs_nid2str(req->rq_peer.nid));
2550                 handle_recovery_req(thread, req,
2551                                     trd->trd_recovery_handler);
2552                 /* Because the waiting client can not send ping to server,
2553                  * so we need refresh the last_request_time, to avoid the
2554                  * export is being evicted */
2555                 ptlrpc_update_export_timer(req->rq_export, 0);
2556                 target_request_copy_put(req);
2557         }
2558
2559         delta = jiffies_to_msecs(jiffies - delta) / MSEC_PER_SEC;
2560         CDEBUG(D_INFO,"4: recovery completed in %lus - %d/%d reqs/locks\n",
2561               delta, obd->obd_replayed_requests, obd->obd_replayed_locks);
2562         if (delta > OBD_RECOVERY_TIME_SOFT) {
2563                 CWARN("too long recovery - read logs\n");
2564                 libcfs_debug_dumplog();
2565         }
2566
2567         target_finish_recovery(lut);
2568
2569         lu_context_fini(&env->le_ctx);
2570         trd->trd_processing_task = 0;
2571         complete(&trd->trd_finishing);
2572
2573         tgt_io_thread_done(thread);
2574         OBD_FREE_PTR(thread);
2575         OBD_FREE_PTR(env);
2576         RETURN(rc);
2577 }
2578
2579 static int target_start_recovery_thread(struct lu_target *lut,
2580                                         svc_handler_t handler)
2581 {
2582         struct obd_device *obd = lut->lut_obd;
2583         int rc = 0;
2584         struct target_recovery_data *trd = &obd->obd_recovery_data;
2585         int index;
2586
2587         memset(trd, 0, sizeof(*trd));
2588         init_completion(&trd->trd_starting);
2589         init_completion(&trd->trd_finishing);
2590         trd->trd_recovery_handler = handler;
2591
2592         rc = server_name2index(obd->obd_name, &index, NULL);
2593         if (rc < 0)
2594                 return rc;
2595
2596         if (!IS_ERR(kthread_run(target_recovery_thread,
2597                                 lut, "tgt_recover_%d", index))) {
2598                 wait_for_completion(&trd->trd_starting);
2599                 LASSERT(obd->obd_recovering != 0);
2600         } else {
2601                 rc = -ECHILD;
2602         }
2603
2604         return rc;
2605 }
2606
2607 void target_stop_recovery_thread(struct obd_device *obd)
2608 {
2609         if (obd->obd_recovery_data.trd_processing_task > 0) {
2610                 struct target_recovery_data *trd = &obd->obd_recovery_data;
2611                 /** recovery can be done but postrecovery is not yet */
2612                 spin_lock(&obd->obd_dev_lock);
2613                 if (obd->obd_recovering) {
2614                         CERROR("%s: Aborting recovery\n", obd->obd_name);
2615                         obd->obd_abort_recovery = 1;
2616                         wake_up(&obd->obd_next_transno_waitq);
2617                 }
2618                 spin_unlock(&obd->obd_dev_lock);
2619                 wait_for_completion(&trd->trd_finishing);
2620         }
2621 }
2622 EXPORT_SYMBOL(target_stop_recovery_thread);
2623
2624 void target_recovery_fini(struct obd_device *obd)
2625 {
2626         class_disconnect_exports(obd);
2627         target_stop_recovery_thread(obd);
2628         target_cleanup_recovery(obd);
2629 }
2630 EXPORT_SYMBOL(target_recovery_fini);
2631
2632 static enum hrtimer_restart target_recovery_expired(struct hrtimer *timer)
2633 {
2634         struct obd_device *obd = container_of(timer, struct obd_device,
2635                                               obd_recovery_timer);
2636
2637         CDEBUG(D_HA,
2638                "%s: recovery timed out; %d clients are still in recovery after %llu seconds (%d clients connected)\n",
2639                obd->obd_name, atomic_read(&obd->obd_lock_replay_clients),
2640                ktime_get_real_seconds() - obd->obd_recovery_start,
2641                atomic_read(&obd->obd_connected_clients));
2642
2643         obd->obd_recovery_expired = 1;
2644         wake_up(&obd->obd_next_transno_waitq);
2645         return HRTIMER_NORESTART;
2646 }
2647
2648 void target_recovery_init(struct lu_target *lut, svc_handler_t handler)
2649 {
2650         struct obd_device *obd = lut->lut_obd;
2651
2652         if (lut->lut_bottom->dd_rdonly)
2653                 return;
2654
2655         if (obd->obd_max_recoverable_clients == 0) {
2656                 /** Update server last boot epoch */
2657                 tgt_boot_epoch_update(lut);
2658                 return;
2659         }
2660
2661         CDEBUG(D_HA, "RECOVERY: service %s, %d recoverable clients, "
2662                "last_transno %llu\n", obd->obd_name,
2663                obd->obd_max_recoverable_clients, obd->obd_last_committed);
2664         LASSERT(obd->obd_stopping == 0);
2665         obd->obd_next_recovery_transno = obd->obd_last_committed + 1;
2666         obd->obd_recovery_start = 0;
2667         obd->obd_recovery_end = 0;
2668
2669         hrtimer_init(&obd->obd_recovery_timer, CLOCK_REALTIME,
2670                      HRTIMER_MODE_REL);
2671         obd->obd_recovery_timer.function = &target_recovery_expired;
2672         target_start_recovery_thread(lut, handler);
2673 }
2674 EXPORT_SYMBOL(target_recovery_init);
2675
2676 static int target_process_req_flags(struct obd_device *obd,
2677                                     struct ptlrpc_request *req)
2678 {
2679         struct obd_export *exp = req->rq_export;
2680         LASSERT(exp != NULL);
2681         if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_REQ_REPLAY_DONE) {
2682                 /* client declares he's ready to replay locks */
2683                 spin_lock(&exp->exp_lock);
2684                 if (exp->exp_req_replay_needed) {
2685                         exp->exp_req_replay_needed = 0;
2686                         spin_unlock(&exp->exp_lock);
2687
2688                         LASSERT_ATOMIC_POS(&obd->obd_req_replay_clients);
2689                         atomic_dec(&obd->obd_req_replay_clients);
2690                 } else {
2691                         spin_unlock(&exp->exp_lock);
2692                 }
2693         }
2694         if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_LOCK_REPLAY_DONE) {
2695                 /* client declares he's ready to complete recovery
2696                  * so, we put the request on th final queue */
2697                 spin_lock(&exp->exp_lock);
2698                 if (exp->exp_lock_replay_needed) {
2699                         exp->exp_lock_replay_needed = 0;
2700                         spin_unlock(&exp->exp_lock);
2701
2702                         LASSERT_ATOMIC_POS(&obd->obd_lock_replay_clients);
2703                         atomic_dec(&obd->obd_lock_replay_clients);
2704                 } else {
2705                         spin_unlock(&exp->exp_lock);
2706                 }
2707         }
2708         return 0;
2709 }
2710
2711 int target_queue_recovery_request(struct ptlrpc_request *req,
2712                                   struct obd_device *obd)
2713 {
2714         __u64 transno = lustre_msg_get_transno(req->rq_reqmsg);
2715         struct ptlrpc_request *reqiter;
2716         int inserted = 0;
2717         ENTRY;
2718
2719         if (obd->obd_recovery_data.trd_processing_task == current_pid()) {
2720                 /* Processing the queue right now, don't re-add. */
2721                 RETURN(1);
2722         }
2723
2724         target_process_req_flags(obd, req);
2725
2726         if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_LOCK_REPLAY_DONE) {
2727                 if (unlikely(OBD_FAIL_CHECK(OBD_FAIL_TGT_RECOVERY_REQ_RACE))) {
2728                         if (cfs_fail_val == 1) {
2729                                 cfs_race_state = 1;
2730                                 cfs_fail_val = 0;
2731                                 wake_up(&cfs_race_waitq);
2732
2733                                 set_current_state(TASK_INTERRUPTIBLE);
2734                                 schedule_timeout(cfs_time_seconds(1));
2735                         }
2736                 }
2737
2738                 /* client declares he's ready to complete recovery
2739                  * so, we put the request on th final queue */
2740                 target_request_copy_get(req);
2741                 DEBUG_REQ(D_HA, req, "queue final req");
2742                 wake_up(&obd->obd_next_transno_waitq);
2743                 spin_lock(&obd->obd_recovery_task_lock);
2744                 if (obd->obd_recovering) {
2745                         struct ptlrpc_request *tmp;
2746                         struct ptlrpc_request *duplicate = NULL;
2747
2748                         if (likely(!req->rq_export->exp_replay_done)) {
2749                                 req->rq_export->exp_replay_done = 1;
2750                                 list_add_tail(&req->rq_list,
2751                                               &obd->obd_final_req_queue);
2752                                 spin_unlock(&obd->obd_recovery_task_lock);
2753                                 RETURN(0);
2754                         }
2755
2756                         /* XXX O(n), but only happens if final ping is
2757                          * timed out, probably reorganize the list as
2758                          * a hash list later */
2759                         list_for_each_entry_safe(reqiter, tmp,
2760                                                  &obd->obd_final_req_queue,
2761                                                  rq_list) {
2762                                 if (reqiter->rq_export == req->rq_export) {
2763                                         list_del_init(&reqiter->rq_list);
2764                                         duplicate = reqiter;
2765                                         break;
2766                                 }
2767                         }
2768
2769                         list_add_tail(&req->rq_list,
2770                                       &obd->obd_final_req_queue);
2771                         req->rq_export->exp_replay_done = 1;
2772                         spin_unlock(&obd->obd_recovery_task_lock);
2773
2774                         if (duplicate != NULL) {
2775                                 DEBUG_REQ(D_HA, duplicate,
2776                                           "put prev final req\n");
2777                                 target_request_copy_put(duplicate);
2778                         }
2779                         RETURN(0);
2780                 } else {
2781                         spin_unlock(&obd->obd_recovery_task_lock);
2782                         target_request_copy_put(req);
2783                         RETURN(obd->obd_stopping ? -ENOTCONN : 1);
2784                 }
2785         }
2786         if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_REQ_REPLAY_DONE) {
2787                 /* client declares he's ready to replay locks */
2788                 target_request_copy_get(req);
2789                 DEBUG_REQ(D_HA, req, "queue lock replay req");
2790                 wake_up(&obd->obd_next_transno_waitq);
2791                 spin_lock(&obd->obd_recovery_task_lock);
2792                 LASSERT(obd->obd_recovering);
2793                 /* usually due to recovery abort */
2794                 if (!req->rq_export->exp_in_recovery) {
2795                         spin_unlock(&obd->obd_recovery_task_lock);
2796                         target_request_copy_put(req);
2797                         RETURN(-ENOTCONN);
2798                 }
2799                 LASSERT(req->rq_export->exp_lock_replay_needed);
2800                 list_add_tail(&req->rq_list, &obd->obd_lock_replay_queue);
2801                 spin_unlock(&obd->obd_recovery_task_lock);
2802                 RETURN(0);
2803         }
2804
2805         /* CAVEAT EMPTOR: The incoming request message has been swabbed
2806          * (i.e. buflens etc are in my own byte order), but type-dependent
2807          * buffers (eg mdt_body, ost_body etc) have NOT been swabbed. */
2808
2809         if (!transno) {
2810                 INIT_LIST_HEAD(&req->rq_list);
2811                 DEBUG_REQ(D_HA, req, "not queueing");
2812                 RETURN(1);
2813         }
2814
2815         /* If we're processing the queue, we want don't want to queue this
2816          * message.
2817          *
2818          * Also, if this request has a transno less than the one we're waiting
2819          * for, we should process it now.  It could (and currently always will)
2820          * be an open request for a descriptor that was opened some time ago.
2821          *
2822          * Also, a resent, replayed request that has already been
2823          * handled will pass through here and be processed immediately.
2824          */
2825         CDEBUG(D_HA, "Next recovery transno: %llu"
2826                ", current: %llu, replaying\n",
2827                obd->obd_next_recovery_transno, transno);
2828
2829         /* If the request has been replayed by update replay, then sends this
2830          * request to the recovery thread (replay_request_or_update()), where
2831          * it will be handled */
2832         spin_lock(&obd->obd_recovery_task_lock);
2833         if (transno < obd->obd_next_recovery_transno &&
2834             !is_req_replayed_by_update(req)) {
2835                 /* Processing the queue right now, don't re-add. */
2836                 LASSERT(list_empty(&req->rq_list));
2837                 spin_unlock(&obd->obd_recovery_task_lock);
2838                 RETURN(1);
2839         }
2840         spin_unlock(&obd->obd_recovery_task_lock);
2841
2842         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_REPLAY_DROP))
2843                 RETURN(0);
2844
2845         target_request_copy_get(req);
2846         if (!req->rq_export->exp_in_recovery) {
2847                 target_request_copy_put(req);
2848                 RETURN(-ENOTCONN);
2849         }
2850         LASSERT(req->rq_export->exp_req_replay_needed);
2851
2852         if (target_exp_enqueue_req_replay(req)) {
2853                 DEBUG_REQ(D_ERROR, req, "dropping resent queued req");
2854                 target_request_copy_put(req);
2855                 RETURN(0);
2856         }
2857
2858         /* XXX O(n^2) */
2859         spin_lock(&obd->obd_recovery_task_lock);
2860         LASSERT(obd->obd_recovering);
2861         list_for_each_entry(reqiter, &obd->obd_req_replay_queue, rq_list) {
2862                 if (lustre_msg_get_transno(reqiter->rq_reqmsg) > transno) {
2863                         list_add_tail(&req->rq_list, &reqiter->rq_list);
2864                         inserted = 1;
2865                         goto added;
2866                 }
2867
2868                 if (unlikely(lustre_msg_get_transno(reqiter->rq_reqmsg) ==
2869                              transno)) {
2870                         DEBUG_REQ(D_ERROR, req, "dropping replay: transno "
2871                                   "has been claimed by another client");
2872                         spin_unlock(&obd->obd_recovery_task_lock);
2873                         target_exp_dequeue_req_replay(req);
2874                         target_request_copy_put(req);
2875                         RETURN(0);
2876                 }
2877         }
2878 added:
2879         if (!inserted)
2880                 list_add_tail(&req->rq_list, &obd->obd_req_replay_queue);
2881
2882         obd->obd_requests_queued_for_recovery++;
2883         spin_unlock(&obd->obd_recovery_task_lock);
2884         wake_up(&obd->obd_next_transno_waitq);
2885         RETURN(0);
2886 }
2887
2888 void target_committed_to_req(struct ptlrpc_request *req)
2889 {
2890         struct obd_export *exp = req->rq_export;
2891
2892         if (!exp->exp_obd->obd_no_transno && req->rq_repmsg != NULL)
2893                 lustre_msg_set_last_committed(req->rq_repmsg,
2894                                               exp->exp_last_committed);
2895         else
2896                 DEBUG_REQ(D_IOCTL, req, "not sending last_committed update (%d/"
2897                           "%d)", exp->exp_obd->obd_no_transno,
2898                           req->rq_repmsg == NULL);
2899
2900         CDEBUG(D_INFO, "last_committed %llu, transno %llu, xid %llu\n",
2901                exp->exp_last_committed, req->rq_transno, req->rq_xid);
2902 }
2903
2904 #endif /* HAVE_SERVER_SUPPORT */
2905
2906 /**
2907  * Packs current SLV and Limit into \a req.
2908  */
2909 int target_pack_pool_reply(struct ptlrpc_request *req)
2910 {
2911         struct obd_device *obd;
2912         ENTRY;
2913
2914         /* Check that we still have all structures alive as this may
2915          * be some late RPC at shutdown time. */
2916         if (unlikely(!req->rq_export || !req->rq_export->exp_obd ||
2917                      !exp_connect_lru_resize(req->rq_export))) {
2918                 lustre_msg_set_slv(req->rq_repmsg, 0);
2919                 lustre_msg_set_limit(req->rq_repmsg, 0);
2920                 RETURN(0);
2921         }
2922
2923         /* OBD is alive here as export is alive, which we checked above. */
2924         obd = req->rq_export->exp_obd;
2925
2926         read_lock(&obd->obd_pool_lock);
2927         lustre_msg_set_slv(req->rq_repmsg, obd->obd_pool_slv);
2928         lustre_msg_set_limit(req->rq_repmsg, obd->obd_pool_limit);
2929         read_unlock(&obd->obd_pool_lock);
2930
2931         RETURN(0);
2932 }
2933
2934 static int target_send_reply_msg(struct ptlrpc_request *req,
2935                                  int rc, int fail_id)
2936 {
2937         if (OBD_FAIL_CHECK_ORSET(fail_id & ~OBD_FAIL_ONCE, OBD_FAIL_ONCE)) {
2938                 DEBUG_REQ(D_ERROR, req, "dropping reply");
2939                 return -ECOMM;
2940         }
2941         /* We can have a null rq_reqmsg in the event of bad signature or
2942          * no context when unwrapping */
2943         if (req->rq_reqmsg &&
2944             unlikely(lustre_msg_get_opc(req->rq_reqmsg) == MDS_REINT &&
2945             OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_MULTI_NET_REP)))
2946                 return -ECOMM;
2947
2948         if (unlikely(rc)) {
2949                 DEBUG_REQ(D_NET, req, "processing error (%d)", rc);
2950                 req->rq_status = rc;
2951                 return ptlrpc_send_error(req, 1);
2952         } else {
2953                 DEBUG_REQ(D_NET, req, "sending reply");
2954         }
2955
2956         return ptlrpc_send_reply(req, PTLRPC_REPLY_MAYBE_DIFFICULT);
2957 }
2958
2959 void target_send_reply(struct ptlrpc_request *req, int rc, int fail_id)
2960 {
2961         struct ptlrpc_service_part *svcpt;
2962         int                        netrc;
2963         struct ptlrpc_reply_state *rs;
2964         struct obd_export         *exp;
2965         ENTRY;
2966
2967         if (req->rq_no_reply) {
2968                 EXIT;
2969                 return;
2970         }
2971
2972         svcpt = req->rq_rqbd->rqbd_svcpt;
2973         rs = req->rq_reply_state;
2974         if (rs == NULL || !rs->rs_difficult) {
2975                 /* no notifiers */
2976                 target_send_reply_msg (req, rc, fail_id);
2977                 EXIT;
2978                 return;
2979         }
2980
2981         /* must be an export if locks saved */
2982         LASSERT(req->rq_export != NULL);
2983         /* req/reply consistent */
2984         LASSERT(rs->rs_svcpt == svcpt);
2985
2986         /* "fresh" reply */
2987         LASSERT(!rs->rs_scheduled);
2988         LASSERT(!rs->rs_scheduled_ever);
2989         LASSERT(!rs->rs_handled);
2990         LASSERT(!rs->rs_on_net);
2991         LASSERT(rs->rs_export == NULL);
2992         LASSERT(list_empty(&rs->rs_obd_list));
2993         LASSERT(list_empty(&rs->rs_exp_list));
2994
2995         exp = class_export_get(req->rq_export);
2996
2997         /* disable reply scheduling while I'm setting up */
2998         rs->rs_scheduled = 1;
2999         rs->rs_on_net    = 1;
3000         rs->rs_xid       = req->rq_xid;
3001         rs->rs_transno   = req->rq_transno;
3002         rs->rs_export    = exp;
3003         rs->rs_opc       = lustre_msg_get_opc(req->rq_reqmsg);
3004
3005         spin_lock(&exp->exp_uncommitted_replies_lock);
3006         CDEBUG(D_NET, "rs transno = %llu, last committed = %llu\n",
3007                rs->rs_transno, exp->exp_last_committed);
3008         if (rs->rs_transno > exp->exp_last_committed) {
3009                 /* not committed already */
3010                 list_add_tail(&rs->rs_obd_list,
3011                                   &exp->exp_uncommitted_replies);
3012         }
3013         spin_unlock(&exp->exp_uncommitted_replies_lock);
3014
3015         spin_lock(&exp->exp_lock);
3016         list_add_tail(&rs->rs_exp_list, &exp->exp_outstanding_replies);
3017         spin_unlock(&exp->exp_lock);
3018
3019         netrc = target_send_reply_msg(req, rc, fail_id);
3020
3021         spin_lock(&svcpt->scp_rep_lock);
3022
3023         atomic_inc(&svcpt->scp_nreps_difficult);
3024
3025         if (netrc != 0) {
3026                 /* error sending: reply is off the net.  Also we need +1
3027                  * reply ref until ptlrpc_handle_rs() is done
3028                  * with the reply state (if the send was successful, there
3029                  * would have been +1 ref for the net, which
3030                  * reply_out_callback leaves alone) */
3031                 rs->rs_on_net = 0;
3032                 ptlrpc_rs_addref(rs);
3033         }
3034
3035         spin_lock(&rs->rs_lock);
3036         if (rs->rs_transno <= exp->exp_last_committed ||
3037             (!rs->rs_on_net && !rs->rs_no_ack) ||
3038             list_empty(&rs->rs_exp_list) ||     /* completed already */
3039             list_empty(&rs->rs_obd_list)) {
3040                 CDEBUG(D_HA, "Schedule reply immediately\n");
3041                 ptlrpc_dispatch_difficult_reply(rs);
3042         } else {
3043                 list_add(&rs->rs_list, &svcpt->scp_rep_active);
3044                 rs->rs_scheduled = 0;   /* allow notifier to schedule */
3045         }
3046         spin_unlock(&rs->rs_lock);
3047         spin_unlock(&svcpt->scp_rep_lock);
3048         EXIT;
3049 }
3050
3051 enum ldlm_mode lck_compat_array[] = {
3052         [LCK_EX]    = LCK_COMPAT_EX,
3053         [LCK_PW]    = LCK_COMPAT_PW,
3054         [LCK_PR]    = LCK_COMPAT_PR,
3055         [LCK_CW]    = LCK_COMPAT_CW,
3056         [LCK_CR]    = LCK_COMPAT_CR,
3057         [LCK_NL]    = LCK_COMPAT_NL,
3058         [LCK_GROUP] = LCK_COMPAT_GROUP,
3059         [LCK_COS]   = LCK_COMPAT_COS,
3060 };
3061
3062 /**
3063  * Rather arbitrary mapping from LDLM error codes to errno values. This should
3064  * not escape to the user level.
3065  */
3066 int ldlm_error2errno(enum ldlm_error error)
3067 {
3068         int result;
3069
3070         switch (error) {
3071         case ELDLM_OK:
3072         case ELDLM_LOCK_MATCHED:
3073                 result = 0;
3074                 break;
3075         case ELDLM_LOCK_CHANGED:
3076                 result = -ESTALE;
3077                 break;
3078         case ELDLM_LOCK_ABORTED:
3079                 result = -ENAVAIL;
3080                 break;
3081         case ELDLM_LOCK_REPLACED:
3082                 result = -ESRCH;
3083                 break;
3084         case ELDLM_NO_LOCK_DATA:
3085                 result = -ENOENT;
3086                 break;
3087         case ELDLM_NAMESPACE_EXISTS:
3088                 result = -EEXIST;
3089                 break;
3090         case ELDLM_BAD_NAMESPACE:
3091                 result = -EBADF;
3092                 break;
3093         default:
3094                 if (((int)error) < 0) { /* cast to signed type */
3095                         result = error; /* as ldlm_error can be unsigned */
3096                 } else {
3097                         CERROR("Invalid DLM result code: %d\n", error);
3098                         result = -EPROTO;
3099                 }
3100         }
3101         return result;
3102 }
3103 EXPORT_SYMBOL(ldlm_error2errno);
3104
3105 /**
3106  * Dual to ldlm_error2errno(): maps errno values back to enum ldlm_error.
3107  */
3108 enum ldlm_error ldlm_errno2error(int err_no)
3109 {
3110         int error;
3111
3112         switch (err_no) {
3113         case 0:
3114                 error = ELDLM_OK;
3115                 break;
3116         case -ESTALE:
3117                 error = ELDLM_LOCK_CHANGED;
3118                 break;
3119         case -ENAVAIL:
3120                 error = ELDLM_LOCK_ABORTED;
3121                 break;
3122         case -ESRCH:
3123                 error = ELDLM_LOCK_REPLACED;
3124                 break;
3125         case -ENOENT:
3126                 error = ELDLM_NO_LOCK_DATA;
3127                 break;
3128         case -EEXIST:
3129                 error = ELDLM_NAMESPACE_EXISTS;
3130                 break;
3131         case -EBADF:
3132                 error = ELDLM_BAD_NAMESPACE;
3133                 break;
3134         default:
3135                 error = err_no;
3136         }
3137         return error;
3138 }
3139
3140 #if LUSTRE_TRACKS_LOCK_EXP_REFS
3141 void ldlm_dump_export_locks(struct obd_export *exp)
3142 {
3143         spin_lock(&exp->exp_locks_list_guard);
3144         if (!list_empty(&exp->exp_locks_list)) {
3145                 struct ldlm_lock *lock;
3146
3147                 CERROR("dumping locks for export %p,"
3148                        "ignore if the unmount doesn't hang\n", exp);
3149                 list_for_each_entry(lock, &exp->exp_locks_list,
3150                                         l_exp_refs_link)
3151                         LDLM_ERROR(lock, "lock:");
3152         }
3153         spin_unlock(&exp->exp_locks_list_guard);
3154 }
3155 #endif
3156
3157 #ifdef HAVE_SERVER_SUPPORT
3158 static int target_bulk_timeout(void *data)
3159 {
3160         ENTRY;
3161         /* We don't fail the connection here, because having the export
3162          * killed makes the (vital) call to commitrw very sad.
3163          */
3164         RETURN(1);
3165 }
3166
3167 static inline const char *bulk2type(struct ptlrpc_request *req)
3168 {