summaryrefslogtreecommitdiff
path: root/fs/dlm/rcom.c
blob: 2e246af4a62c26dcf814744d385db837a214f86f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
/******************************************************************************
*******************************************************************************
**
**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
**  Copyright (C) 2005 Red Hat, Inc.  All rights reserved.
**
**  This copyrighted material is made available to anyone wishing to use,
**  modify, copy, or redistribute it subject to the terms and conditions
**  of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/

#include "dlm_internal.h"
#include "lockspace.h"
#include "member.h"
#include "lowcomms.h"
#include "midcomms.h"
#include "rcom.h"
#include "recover.h"
#include "dir.h"
#include "config.h"
#include "memory.h"
#include "lock.h"
#include "util.h"


static int rcom_response(struct dlm_ls *ls)
{
	return test_bit(LSFL_RCOM_READY, &ls->ls_flags);
}

static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len,
		       struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	char *mb;
	int mb_len = sizeof(struct dlm_rcom) + len;

	mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb);
	if (!mh) {
		log_print("create_rcom to %d type %d len %d ENOBUFS",
			  to_nodeid, type, len);
		return -ENOBUFS;
	}
	memset(mb, 0, mb_len);

	rc = (struct dlm_rcom *) mb;

	rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
	rc->rc_header.h_lockspace = ls->ls_global_id;
	rc->rc_header.h_nodeid = dlm_our_nodeid();
	rc->rc_header.h_length = mb_len;
	rc->rc_header.h_cmd = DLM_RCOM;

	rc->rc_type = type;

	spin_lock(&ls->ls_recover_lock);
	rc->rc_seq = ls->ls_recover_seq;
	spin_unlock(&ls->ls_recover_lock);

	*mh_ret = mh;
	*rc_ret = rc;
	return 0;
}

static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh,
		      struct dlm_rcom *rc)
{
	dlm_rcom_out(rc);
	dlm_lowcomms_commit_buffer(mh);
}

/* When replying to a status request, a node also sends back its
   configuration values.  The requesting node then checks that the remote
   node is configured the same way as itself. */

static void make_config(struct dlm_ls *ls, struct rcom_config *rf)
{
	rf->rf_lvblen = ls->ls_lvblen;
	rf->rf_lsflags = ls->ls_exflags;
}

static int check_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
{
	struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;

	if ((rc->rc_header.h_version & 0xFFFF0000) != DLM_HEADER_MAJOR) {
		log_error(ls, "version mismatch: %x nodeid %d: %x",
			  DLM_HEADER_MAJOR | DLM_HEADER_MINOR, nodeid,
			  rc->rc_header.h_version);
		return -EINVAL;
	}

	if (rf->rf_lvblen != ls->ls_lvblen ||
	    rf->rf_lsflags != ls->ls_exflags) {
		log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
			  ls->ls_lvblen, ls->ls_exflags,
			  nodeid, rf->rf_lvblen, rf->rf_lsflags);
		return -EINVAL;
	}
	return 0;
}

static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
{
	spin_lock(&ls->ls_rcom_spin);
	*new_seq = ++ls->ls_rcom_seq;
	set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
	spin_unlock(&ls->ls_rcom_spin);
}

static void disallow_sync_reply(struct dlm_ls *ls)
{
	spin_lock(&ls->ls_rcom_spin);
	clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
	clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
	spin_unlock(&ls->ls_rcom_spin);
}

int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error = 0;

	ls->ls_recover_nodeid = nodeid;

	if (nodeid == dlm_our_nodeid()) {
		rc = (struct dlm_rcom *) ls->ls_recover_buf;
		rc->rc_result = dlm_recover_status(ls);
		goto out;
	}

	error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
	if (error)
		goto out;

	allow_sync_reply(ls, &rc->rc_id);
	memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);

	send_rcom(ls, mh, rc);

	error = dlm_wait_function(ls, &rcom_response);
	disallow_sync_reply(ls);
	if (error)
		goto out;

	rc = (struct dlm_rcom *) ls->ls_recover_buf;

	if (rc->rc_result == -ESRCH) {
		/* we pretend the remote lockspace exists with 0 status */
		log_debug(ls, "remote node %d not ready", nodeid);
		rc->rc_result = 0;
	} else
		error = check_config(ls, rc, nodeid);
	/* the caller looks at rc_result for the remote recovery status */
 out:
	return error;
}

static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error, nodeid = rc_in->rc_header.h_nodeid;

	error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
			    sizeof(struct rcom_config), &rc, &mh);
	if (error)
		return;
	rc->rc_id = rc_in->rc_id;
	rc->rc_seq_reply = rc_in->rc_seq;
	rc->rc_result = dlm_recover_status(ls);
	make_config(ls, (struct rcom_config *) rc->rc_buf);

	send_rcom(ls, mh, rc);
}

static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	spin_lock(&ls->ls_rcom_spin);
	if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
	    rc_in->rc_id != ls->ls_rcom_seq) {
		log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
			  rc_in->rc_type, rc_in->rc_header.h_nodeid,
			  (unsigned long long)rc_in->rc_id,
			  (unsigned long long)ls->ls_rcom_seq);
		goto out;
	}
	memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
	set_bit(LSFL_RCOM_READY, &ls->ls_flags);
	clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
	wake_up(&ls->ls_wait_general);
 out:
	spin_unlock(&ls->ls_rcom_spin);
}

static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	receive_sync_reply(ls, rc_in);
}

int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error = 0, len = sizeof(struct dlm_rcom);

	ls->ls_recover_nodeid = nodeid;

	if (nodeid == dlm_our_nodeid()) {
		dlm_copy_master_names(ls, last_name, last_len,
		                      ls->ls_recover_buf + len,
		                      dlm_config.buffer_size - len, nodeid);
		goto out;
	}

	error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
	if (error)
		goto out;
	memcpy(rc->rc_buf, last_name, last_len);

	allow_sync_reply(ls, &rc->rc_id);
	memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);

	send_rcom(ls, mh, rc);

	error = dlm_wait_function(ls, &rcom_response);
	disallow_sync_reply(ls);
 out:
	return error;
}

static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error, inlen, outlen, nodeid;

	nodeid = rc_in->rc_header.h_nodeid;
	inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
	outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom);

	error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
	if (error)
		return;
	rc->rc_id = rc_in->rc_id;
	rc->rc_seq_reply = rc_in->rc_seq;

	dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
			      nodeid);
	send_rcom(ls, mh, rc);
}

static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	receive_sync_reply(ls, rc_in);
}

int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	struct dlm_ls *ls = r->res_ls;
	int error;

	error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
			    &rc, &mh);
	if (error)
		goto out;
	memcpy(rc->rc_buf, r->res_name, r->res_length);
	rc->rc_id = (unsigned long) r;

	send_rcom(ls, mh, rc);
 out:
	return error;
}

static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
	int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);

	error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
	if (error)
		return;

	error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
	if (error)
		ret_nodeid = error;
	rc->rc_result = ret_nodeid;
	rc->rc_id = rc_in->rc_id;
	rc->rc_seq_reply = rc_in->rc_seq;

	send_rcom(ls, mh, rc);
}

static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	dlm_recover_master_reply(ls, rc_in);
}

static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
			   struct rcom_lock *rl)
{
	memset(rl, 0, sizeof(*rl));

	rl->rl_ownpid = lkb->lkb_ownpid;
	rl->rl_lkid = lkb->lkb_id;
	rl->rl_exflags = lkb->lkb_exflags;
	rl->rl_flags = lkb->lkb_flags;
	rl->rl_lvbseq = lkb->lkb_lvbseq;
	rl->rl_rqmode = lkb->lkb_rqmode;
	rl->rl_grmode = lkb->lkb_grmode;
	rl->rl_status = lkb->lkb_status;
	rl->rl_wait_type = lkb->lkb_wait_type;

	if (lkb->lkb_bastaddr)
		rl->rl_asts |= AST_BAST;
	if (lkb->lkb_astaddr)
		rl->rl_asts |= AST_COMP;

	rl->rl_namelen = r->res_length;
	memcpy(rl->rl_name, r->res_name, r->res_length);

	/* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
	   If so, receive_rcom_lock_args() won't take this copy. */

	if (lkb->lkb_lvbptr)
		memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
}

int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
{
	struct dlm_ls *ls = r->res_ls;
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	struct rcom_lock *rl;
	int error, len = sizeof(struct rcom_lock);

	if (lkb->lkb_lvbptr)
		len += ls->ls_lvblen;

	error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
	if (error)
		goto out;

	rl = (struct rcom_lock *) rc->rc_buf;
	pack_rcom_lock(r, lkb, rl);
	rc->rc_id = (unsigned long) r;

	send_rcom(ls, mh, rc);
 out:
	return error;
}

static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	struct dlm_rcom *rc;
	struct dlm_mhandle *mh;
	int error, nodeid = rc_in->rc_header.h_nodeid;

	dlm_recover_master_copy(ls, rc_in);

	error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
			    sizeof(struct rcom_lock), &rc, &mh);
	if (error)
		return;

	/* We send back the same rcom_lock struct we received, but
	   dlm_recover_master_copy() has filled in rl_remid and rl_result */

	memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
	rc->rc_id = rc_in->rc_id;
	rc->rc_seq_reply = rc_in->rc_seq;

	send_rcom(ls, mh, rc);
}

static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
	dlm_recover_process_copy(ls, rc_in);
}

static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
{
	struct dlm_rcom *rc;
	struct rcom_config *rf;
	struct dlm_mhandle *mh;
	char *mb;
	int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);

	mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
	if (!mh)
		return -ENOBUFS;
	memset(mb, 0, mb_len);

	rc = (struct dlm_rcom *) mb;

	rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
	rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
	rc->rc_header.h_nodeid = dlm_our_nodeid();
	rc->rc_header.h_length = mb_len;
	rc->rc_header.h_cmd = DLM_RCOM;

	rc->rc_type = DLM_RCOM_STATUS_REPLY;
	rc->rc_id = rc_in->rc_id;
	rc->rc_seq_reply = rc_in->rc_seq;
	rc->rc_result = -ESRCH;

	rf = (struct rcom_config *) rc->rc_buf;
	rf->rf_lvblen = -1;

	dlm_rcom_out(rc);
	dlm_lowcomms_commit_buffer(mh);

	return 0;
}

static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
{
	uint64_t seq;
	int rv = 0;

	switch (rc->rc_type) {
	case DLM_RCOM_STATUS_REPLY:
	case DLM_RCOM_NAMES_REPLY:
	case DLM_RCOM_LOOKUP_REPLY:
	case DLM_RCOM_LOCK_REPLY:
		spin_lock(&ls->ls_recover_lock);
		seq = ls->ls_recover_seq;
		spin_unlock(&ls->ls_recover_lock);
		if (rc->rc_seq_reply != seq) {
			log_debug(ls, "ignoring old reply %x from %d "
				      "seq_reply %llx expect %llx",
				      rc->rc_type, rc->rc_header.h_nodeid,
				      (unsigned long long)rc->rc_seq_reply,
				      (unsigned long long)seq);
			rv = 1;
		}
	}
	return rv;
}

/* Called by dlm_recvd; corresponds to dlm_receive_message() but special
   recovery-only comms are sent through here. */

void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
{
	struct dlm_rcom *rc = (struct dlm_rcom *) hd;
	struct dlm_ls *ls;

	dlm_rcom_in(rc);

	/* If the lockspace doesn't exist then still send a status message
	   back; it's possible that it just doesn't have its global_id yet. */

	ls = dlm_find_lockspace_global(hd->h_lockspace);
	if (!ls) {
		log_print("lockspace %x from %d type %x not found",
			  hd->h_lockspace, nodeid, rc->rc_type);
		if (rc->rc_type == DLM_RCOM_STATUS)
			send_ls_not_ready(nodeid, rc);
		return;
	}

	if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
		log_debug(ls, "ignoring recovery message %x from %d",
			  rc->rc_type, nodeid);
		goto out;
	}

	if (is_old_reply(ls, rc))
		goto out;

	if (nodeid != rc->rc_header.h_nodeid) {
		log_error(ls, "bad rcom nodeid %d from %d",
			  rc->rc_header.h_nodeid, nodeid);
		goto out;
	}

	switch (rc->rc_type) {
	case DLM_RCOM_STATUS:
		receive_rcom_status(ls, rc);
		break;

	case DLM_RCOM_NAMES:
		receive_rcom_names(ls, rc);
		break;

	case DLM_RCOM_LOOKUP:
		receive_rcom_lookup(ls, rc);
		break;

	case DLM_RCOM_LOCK:
		receive_rcom_lock(ls, rc);
		break;

	case DLM_RCOM_STATUS_REPLY:
		receive_rcom_status_reply(ls, rc);
		break;

	case DLM_RCOM_NAMES_REPLY:
		receive_rcom_names_reply(ls, rc);
		break;

	case DLM_RCOM_LOOKUP_REPLY:
		receive_rcom_lookup_reply(ls, rc);
		break;

	case DLM_RCOM_LOCK_REPLY:
		receive_rcom_lock_reply(ls, rc);
		break;

	default:
		DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
	}
 out:
	dlm_put_lockspace(ls);
}