1/******************************************************************************
2*******************************************************************************
3**
4**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
6**
7**  This copyrighted material is made available to anyone wishing to use,
8**  modify, copy, or redistribute it subject to the terms and conditions
9**  of the GNU General Public License v.2.
10**
11*******************************************************************************
12******************************************************************************/
13
14#include "dlm_internal.h"
15#include "lockspace.h"
16#include "member.h"
17#include "lowcomms.h"
18#include "midcomms.h"
19#include "rcom.h"
20#include "recover.h"
21#include "dir.h"
22#include "config.h"
23#include "memory.h"
24#include "lock.h"
25#include "util.h"
26
27static int rcom_response(struct dlm_ls *ls)
28{
29	return test_bit(LSFL_RCOM_READY, &ls->ls_flags);
30}
31
32static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len,
33		       struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret)
34{
35	struct dlm_rcom *rc;
36	struct dlm_mhandle *mh;
37	char *mb;
38	int mb_len = sizeof(struct dlm_rcom) + len;
39
40	mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
41	if (!mh) {
42		log_print("create_rcom to %d type %d len %d ENOBUFS",
43			  to_nodeid, type, len);
44		return -ENOBUFS;
45	}
46	memset(mb, 0, mb_len);
47
48	rc = (struct dlm_rcom *) mb;
49
50	rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
51	rc->rc_header.h_lockspace = ls->ls_global_id;
52	rc->rc_header.h_nodeid = dlm_our_nodeid();
53	rc->rc_header.h_length = mb_len;
54	rc->rc_header.h_cmd = DLM_RCOM;
55
56	rc->rc_type = type;
57
58	spin_lock(&ls->ls_recover_lock);
59	rc->rc_seq = ls->ls_recover_seq;
60	spin_unlock(&ls->ls_recover_lock);
61
62	*mh_ret = mh;
63	*rc_ret = rc;
64	return 0;
65}
66
67static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh,
68		      struct dlm_rcom *rc)
69{
70	dlm_rcom_out(rc);
71	dlm_lowcomms_commit_buffer(mh);
72}
73
74static void set_rcom_status(struct dlm_ls *ls, struct rcom_status *rs,
75			    uint32_t flags)
76{
77	rs->rs_flags = cpu_to_le32(flags);
78}
79
80/* When replying to a status request, a node also sends back its
81   configuration values.  The requesting node then checks that the remote
82   node is configured the same way as itself. */
83
84static void set_rcom_config(struct dlm_ls *ls, struct rcom_config *rf,
85			    uint32_t num_slots)
86{
87	rf->rf_lvblen = cpu_to_le32(ls->ls_lvblen);
88	rf->rf_lsflags = cpu_to_le32(ls->ls_exflags);
89
90	rf->rf_our_slot = cpu_to_le16(ls->ls_slot);
91	rf->rf_num_slots = cpu_to_le16(num_slots);
92	rf->rf_generation =  cpu_to_le32(ls->ls_generation);
93}
94
95static int check_rcom_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
96{
97	struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;
98
99	if ((rc->rc_header.h_version & 0xFFFF0000) != DLM_HEADER_MAJOR) {
100		log_error(ls, "version mismatch: %x nodeid %d: %x",
101			  DLM_HEADER_MAJOR | DLM_HEADER_MINOR, nodeid,
102			  rc->rc_header.h_version);
103		return -EPROTO;
104	}
105
106	if (le32_to_cpu(rf->rf_lvblen) != ls->ls_lvblen ||
107	    le32_to_cpu(rf->rf_lsflags) != ls->ls_exflags) {
108		log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
109			  ls->ls_lvblen, ls->ls_exflags, nodeid,
110			  le32_to_cpu(rf->rf_lvblen),
111			  le32_to_cpu(rf->rf_lsflags));
112		return -EPROTO;
113	}
114	return 0;
115}
116
117static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
118{
119	spin_lock(&ls->ls_rcom_spin);
120	*new_seq = ++ls->ls_rcom_seq;
121	set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
122	spin_unlock(&ls->ls_rcom_spin);
123}
124
125static void disallow_sync_reply(struct dlm_ls *ls)
126{
127	spin_lock(&ls->ls_rcom_spin);
128	clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
129	clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
130	spin_unlock(&ls->ls_rcom_spin);
131}
132
133/*
134 * low nodeid gathers one slot value at a time from each node.
135 * it sets need_slots=0, and saves rf_our_slot returned from each
136 * rcom_config.
137 *
138 * other nodes gather all slot values at once from the low nodeid.
139 * they set need_slots=1, and ignore the rf_our_slot returned from each
140 * rcom_config.  they use the rf_num_slots returned from the low
141 * node's rcom_config.
142 */
143
144int dlm_rcom_status(struct dlm_ls *ls, int nodeid, uint32_t status_flags)
145{
146	struct dlm_rcom *rc;
147	struct dlm_mhandle *mh;
148	int error = 0;
149
150	ls->ls_recover_nodeid = nodeid;
151
152	if (nodeid == dlm_our_nodeid()) {
153		rc = ls->ls_recover_buf;
154		rc->rc_result = dlm_recover_status(ls);
155		goto out;
156	}
157
158	error = create_rcom(ls, nodeid, DLM_RCOM_STATUS,
159			    sizeof(struct rcom_status), &rc, &mh);
160	if (error)
161		goto out;
162
163	set_rcom_status(ls, (struct rcom_status *)rc->rc_buf, status_flags);
164
165	allow_sync_reply(ls, &rc->rc_id);
166	memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
167
168	send_rcom(ls, mh, rc);
169
170	error = dlm_wait_function(ls, &rcom_response);
171	disallow_sync_reply(ls);
172	if (error)
173		goto out;
174
175	rc = ls->ls_recover_buf;
176
177	if (rc->rc_result == -ESRCH) {
178		/* we pretend the remote lockspace exists with 0 status */
179		log_debug(ls, "remote node %d not ready", nodeid);
180		rc->rc_result = 0;
181		error = 0;
182	} else {
183		error = check_rcom_config(ls, rc, nodeid);
184	}
185
186	/* the caller looks at rc_result for the remote recovery status */
187 out:
188	return error;
189}
190
191static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
192{
193	struct dlm_rcom *rc;
194	struct dlm_mhandle *mh;
195	struct rcom_status *rs;
196	uint32_t status;
197	int nodeid = rc_in->rc_header.h_nodeid;
198	int len = sizeof(struct rcom_config);
199	int num_slots = 0;
200	int error;
201
202	if (!dlm_slots_version(&rc_in->rc_header)) {
203		status = dlm_recover_status(ls);
204		goto do_create;
205	}
206
207	rs = (struct rcom_status *)rc_in->rc_buf;
208
209	if (!(le32_to_cpu(rs->rs_flags) & DLM_RSF_NEED_SLOTS)) {
210		status = dlm_recover_status(ls);
211		goto do_create;
212	}
213
214	spin_lock(&ls->ls_recover_lock);
215	status = ls->ls_recover_status;
216	num_slots = ls->ls_num_slots;
217	spin_unlock(&ls->ls_recover_lock);
218	len += num_slots * sizeof(struct rcom_slot);
219
220 do_create:
221	error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
222			    len, &rc, &mh);
223	if (error)
224		return;
225
226	rc->rc_id = rc_in->rc_id;
227	rc->rc_seq_reply = rc_in->rc_seq;
228	rc->rc_result = status;
229
230	set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, num_slots);
231
232	if (!num_slots)
233		goto do_send;
234
235	spin_lock(&ls->ls_recover_lock);
236	if (ls->ls_num_slots != num_slots) {
237		spin_unlock(&ls->ls_recover_lock);
238		log_debug(ls, "receive_rcom_status num_slots %d to %d",
239			  num_slots, ls->ls_num_slots);
240		rc->rc_result = 0;
241		set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, 0);
242		goto do_send;
243	}
244
245	dlm_slots_copy_out(ls, rc);
246	spin_unlock(&ls->ls_recover_lock);
247
248 do_send:
249	send_rcom(ls, mh, rc);
250}
251
252static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
253{
254	spin_lock(&ls->ls_rcom_spin);
255	if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
256	    rc_in->rc_id != ls->ls_rcom_seq) {
257		log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
258			  rc_in->rc_type, rc_in->rc_header.h_nodeid,
259			  (unsigned long long)rc_in->rc_id,
260			  (unsigned long long)ls->ls_rcom_seq);
261		goto out;
262	}
263	memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
264	set_bit(LSFL_RCOM_READY, &ls->ls_flags);
265	clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
266	wake_up(&ls->ls_wait_general);
267 out:
268	spin_unlock(&ls->ls_rcom_spin);
269}
270
271int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
272{
273	struct dlm_rcom *rc;
274	struct dlm_mhandle *mh;
275	int error = 0;
276
277	ls->ls_recover_nodeid = nodeid;
278
279	error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
280	if (error)
281		goto out;
282	memcpy(rc->rc_buf, last_name, last_len);
283
284	allow_sync_reply(ls, &rc->rc_id);
285	memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
286
287	send_rcom(ls, mh, rc);
288
289	error = dlm_wait_function(ls, &rcom_response);
290	disallow_sync_reply(ls);
291 out:
292	return error;
293}
294
295static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
296{
297	struct dlm_rcom *rc;
298	struct dlm_mhandle *mh;
299	int error, inlen, outlen, nodeid;
300
301	nodeid = rc_in->rc_header.h_nodeid;
302	inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
303	outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
304
305	error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
306	if (error)
307		return;
308	rc->rc_id = rc_in->rc_id;
309	rc->rc_seq_reply = rc_in->rc_seq;
310
311	dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
312			      nodeid);
313	send_rcom(ls, mh, rc);
314}
315
316int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
317{
318	struct dlm_rcom *rc;
319	struct dlm_mhandle *mh;
320	struct dlm_ls *ls = r->res_ls;
321	int error;
322
323	error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
324			    &rc, &mh);
325	if (error)
326		goto out;
327	memcpy(rc->rc_buf, r->res_name, r->res_length);
328	rc->rc_id = (unsigned long) r->res_id;
329
330	send_rcom(ls, mh, rc);
331 out:
332	return error;
333}
334
335int dlm_send_rcom_lookup_dump(struct dlm_rsb *r, int to_nodeid)
336{
337	struct dlm_rcom *rc;
338	struct dlm_mhandle *mh;
339	struct dlm_ls *ls = r->res_ls;
340	int error;
341
342	error = create_rcom(ls, to_nodeid, DLM_RCOM_LOOKUP, r->res_length,
343			    &rc, &mh);
344	if (error)
345		goto out;
346	memcpy(rc->rc_buf, r->res_name, r->res_length);
347	rc->rc_id = 0xFFFFFFFF;
348
349	send_rcom(ls, mh, rc);
350 out:
351	return error;
352}
353
354static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
355{
356	struct dlm_rcom *rc;
357	struct dlm_mhandle *mh;
358	int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
359	int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
360
361	error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
362	if (error)
363		return;
364
365	if (rc_in->rc_id == 0xFFFFFFFF) {
366		log_error(ls, "receive_rcom_lookup dump from %d", nodeid);
367		dlm_dump_rsb_name(ls, rc_in->rc_buf, len);
368		return;
369	}
370
371	error = dlm_master_lookup(ls, nodeid, rc_in->rc_buf, len,
372				  DLM_LU_RECOVER_MASTER, &ret_nodeid, NULL);
373	if (error)
374		ret_nodeid = error;
375	rc->rc_result = ret_nodeid;
376	rc->rc_id = rc_in->rc_id;
377	rc->rc_seq_reply = rc_in->rc_seq;
378
379	send_rcom(ls, mh, rc);
380}
381
382static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
383{
384	dlm_recover_master_reply(ls, rc_in);
385}
386
387static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
388			   struct rcom_lock *rl)
389{
390	memset(rl, 0, sizeof(*rl));
391
392	rl->rl_ownpid = cpu_to_le32(lkb->lkb_ownpid);
393	rl->rl_lkid = cpu_to_le32(lkb->lkb_id);
394	rl->rl_exflags = cpu_to_le32(lkb->lkb_exflags);
395	rl->rl_flags = cpu_to_le32(lkb->lkb_flags);
396	rl->rl_lvbseq = cpu_to_le32(lkb->lkb_lvbseq);
397	rl->rl_rqmode = lkb->lkb_rqmode;
398	rl->rl_grmode = lkb->lkb_grmode;
399	rl->rl_status = lkb->lkb_status;
400	rl->rl_wait_type = cpu_to_le16(lkb->lkb_wait_type);
401
402	if (lkb->lkb_bastfn)
403		rl->rl_asts |= DLM_CB_BAST;
404	if (lkb->lkb_astfn)
405		rl->rl_asts |= DLM_CB_CAST;
406
407	rl->rl_namelen = cpu_to_le16(r->res_length);
408	memcpy(rl->rl_name, r->res_name, r->res_length);
409
410	/* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
411	   If so, receive_rcom_lock_args() won't take this copy. */
412
413	if (lkb->lkb_lvbptr)
414		memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
415}
416
417int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
418{
419	struct dlm_ls *ls = r->res_ls;
420	struct dlm_rcom *rc;
421	struct dlm_mhandle *mh;
422	struct rcom_lock *rl;
423	int error, len = sizeof(struct rcom_lock);
424
425	if (lkb->lkb_lvbptr)
426		len += ls->ls_lvblen;
427
428	error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
429	if (error)
430		goto out;
431
432	rl = (struct rcom_lock *) rc->rc_buf;
433	pack_rcom_lock(r, lkb, rl);
434	rc->rc_id = (unsigned long) r;
435
436	send_rcom(ls, mh, rc);
437 out:
438	return error;
439}
440
441/* needs at least dlm_rcom + rcom_lock */
442static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
443{
444	struct dlm_rcom *rc;
445	struct dlm_mhandle *mh;
446	int error, nodeid = rc_in->rc_header.h_nodeid;
447
448	dlm_recover_master_copy(ls, rc_in);
449
450	error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
451			    sizeof(struct rcom_lock), &rc, &mh);
452	if (error)
453		return;
454
455	/* We send back the same rcom_lock struct we received, but
456	   dlm_recover_master_copy() has filled in rl_remid and rl_result */
457
458	memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
459	rc->rc_id = rc_in->rc_id;
460	rc->rc_seq_reply = rc_in->rc_seq;
461
462	send_rcom(ls, mh, rc);
463}
464
465/* If the lockspace doesn't exist then still send a status message
466   back; it's possible that it just doesn't have its global_id yet. */
467
468int dlm_send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
469{
470	struct dlm_rcom *rc;
471	struct rcom_config *rf;
472	struct dlm_mhandle *mh;
473	char *mb;
474	int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
475
476	mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_NOFS, &mb);
477	if (!mh)
478		return -ENOBUFS;
479	memset(mb, 0, mb_len);
480
481	rc = (struct dlm_rcom *) mb;
482
483	rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
484	rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
485	rc->rc_header.h_nodeid = dlm_our_nodeid();
486	rc->rc_header.h_length = mb_len;
487	rc->rc_header.h_cmd = DLM_RCOM;
488
489	rc->rc_type = DLM_RCOM_STATUS_REPLY;
490	rc->rc_id = rc_in->rc_id;
491	rc->rc_seq_reply = rc_in->rc_seq;
492	rc->rc_result = -ESRCH;
493
494	rf = (struct rcom_config *) rc->rc_buf;
495	rf->rf_lvblen = cpu_to_le32(~0U);
496
497	dlm_rcom_out(rc);
498	dlm_lowcomms_commit_buffer(mh);
499
500	return 0;
501}
502
503/*
504 * Ignore messages for stage Y before we set
505 * recover_status bit for stage X:
506 *
507 * recover_status = 0
508 *
509 * dlm_recover_members()
510 * - send nothing
511 * - recv nothing
512 * - ignore NAMES, NAMES_REPLY
513 * - ignore LOOKUP, LOOKUP_REPLY
514 * - ignore LOCK, LOCK_REPLY
515 *
516 * recover_status |= NODES
517 *
518 * dlm_recover_members_wait()
519 *
520 * dlm_recover_directory()
521 * - send NAMES
522 * - recv NAMES_REPLY
523 * - ignore LOOKUP, LOOKUP_REPLY
524 * - ignore LOCK, LOCK_REPLY
525 *
526 * recover_status |= DIR
527 *
528 * dlm_recover_directory_wait()
529 *
530 * dlm_recover_masters()
531 * - send LOOKUP
532 * - recv LOOKUP_REPLY
533 *
534 * dlm_recover_locks()
535 * - send LOCKS
536 * - recv LOCKS_REPLY
537 *
538 * recover_status |= LOCKS
539 *
540 * dlm_recover_locks_wait()
541 *
542 * recover_status |= DONE
543 */
544
545/* Called by dlm_recv; corresponds to dlm_receive_message() but special
546   recovery-only comms are sent through here. */
547
548void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
549{
550	int lock_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_lock);
551	int stop, reply = 0, names = 0, lookup = 0, lock = 0;
552	uint32_t status;
553	uint64_t seq;
554
555	switch (rc->rc_type) {
556	case DLM_RCOM_STATUS_REPLY:
557		reply = 1;
558		break;
559	case DLM_RCOM_NAMES:
560		names = 1;
561		break;
562	case DLM_RCOM_NAMES_REPLY:
563		names = 1;
564		reply = 1;
565		break;
566	case DLM_RCOM_LOOKUP:
567		lookup = 1;
568		break;
569	case DLM_RCOM_LOOKUP_REPLY:
570		lookup = 1;
571		reply = 1;
572		break;
573	case DLM_RCOM_LOCK:
574		lock = 1;
575		break;
576	case DLM_RCOM_LOCK_REPLY:
577		lock = 1;
578		reply = 1;
579		break;
580	};
581
582	spin_lock(&ls->ls_recover_lock);
583	status = ls->ls_recover_status;
584	stop = test_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
585	seq = ls->ls_recover_seq;
586	spin_unlock(&ls->ls_recover_lock);
587
588	if (stop && (rc->rc_type != DLM_RCOM_STATUS))
589		goto ignore;
590
591	if (reply && (rc->rc_seq_reply != seq))
592		goto ignore;
593
594	if (!(status & DLM_RS_NODES) && (names || lookup || lock))
595		goto ignore;
596
597	if (!(status & DLM_RS_DIR) && (lookup || lock))
598		goto ignore;
599
600	switch (rc->rc_type) {
601	case DLM_RCOM_STATUS:
602		receive_rcom_status(ls, rc);
603		break;
604
605	case DLM_RCOM_NAMES:
606		receive_rcom_names(ls, rc);
607		break;
608
609	case DLM_RCOM_LOOKUP:
610		receive_rcom_lookup(ls, rc);
611		break;
612
613	case DLM_RCOM_LOCK:
614		if (rc->rc_header.h_length < lock_size)
615			goto Eshort;
616		receive_rcom_lock(ls, rc);
617		break;
618
619	case DLM_RCOM_STATUS_REPLY:
620		receive_sync_reply(ls, rc);
621		break;
622
623	case DLM_RCOM_NAMES_REPLY:
624		receive_sync_reply(ls, rc);
625		break;
626
627	case DLM_RCOM_LOOKUP_REPLY:
628		receive_rcom_lookup_reply(ls, rc);
629		break;
630
631	case DLM_RCOM_LOCK_REPLY:
632		if (rc->rc_header.h_length < lock_size)
633			goto Eshort;
634		dlm_recover_process_copy(ls, rc);
635		break;
636
637	default:
638		log_error(ls, "receive_rcom bad type %d", rc->rc_type);
639	}
640	return;
641
642ignore:
643	log_limit(ls, "dlm_receive_rcom ignore msg %d "
644		  "from %d %llu %llu recover seq %llu sts %x gen %u",
645		   rc->rc_type,
646		   nodeid,
647		   (unsigned long long)rc->rc_seq,
648		   (unsigned long long)rc->rc_seq_reply,
649		   (unsigned long long)seq,
650		   status, ls->ls_generation);
651	return;
652Eshort:
653	log_error(ls, "recovery message %d from %d is too short",
654		  rc->rc_type, nodeid);
655}
656
657