GNU Linux-libre 4.19.245-gnu1
[releases.git] / fs / dlm / rcom.c
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
27 static int rcom_response(struct dlm_ls *ls)
28 {
29         return test_bit(LSFL_RCOM_READY, &ls->ls_flags);
30 }
31
32 static 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
67 static 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
74 static 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
84 static 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
95 static 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
117 static 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
125 static 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
144 int 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 retry:
159         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS,
160                             sizeof(struct rcom_status), &rc, &mh);
161         if (error)
162                 goto out;
163
164         set_rcom_status(ls, (struct rcom_status *)rc->rc_buf, status_flags);
165
166         allow_sync_reply(ls, &rc->rc_id);
167         memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
168
169         send_rcom(ls, mh, rc);
170
171         error = dlm_wait_function(ls, &rcom_response);
172         disallow_sync_reply(ls);
173         if (error == -ETIMEDOUT)
174                 goto retry;
175         if (error)
176                 goto out;
177
178         rc = ls->ls_recover_buf;
179
180         if (rc->rc_result == -ESRCH) {
181                 /* we pretend the remote lockspace exists with 0 status */
182                 log_debug(ls, "remote node %d not ready", nodeid);
183                 rc->rc_result = 0;
184                 error = 0;
185         } else {
186                 error = check_rcom_config(ls, rc, nodeid);
187         }
188
189         /* the caller looks at rc_result for the remote recovery status */
190  out:
191         return error;
192 }
193
194 static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
195 {
196         struct dlm_rcom *rc;
197         struct dlm_mhandle *mh;
198         struct rcom_status *rs;
199         uint32_t status;
200         int nodeid = rc_in->rc_header.h_nodeid;
201         int len = sizeof(struct rcom_config);
202         int num_slots = 0;
203         int error;
204
205         if (!dlm_slots_version(&rc_in->rc_header)) {
206                 status = dlm_recover_status(ls);
207                 goto do_create;
208         }
209
210         rs = (struct rcom_status *)rc_in->rc_buf;
211
212         if (!(le32_to_cpu(rs->rs_flags) & DLM_RSF_NEED_SLOTS)) {
213                 status = dlm_recover_status(ls);
214                 goto do_create;
215         }
216
217         spin_lock(&ls->ls_recover_lock);
218         status = ls->ls_recover_status;
219         num_slots = ls->ls_num_slots;
220         spin_unlock(&ls->ls_recover_lock);
221         len += num_slots * sizeof(struct rcom_slot);
222
223  do_create:
224         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
225                             len, &rc, &mh);
226         if (error)
227                 return;
228
229         rc->rc_id = rc_in->rc_id;
230         rc->rc_seq_reply = rc_in->rc_seq;
231         rc->rc_result = status;
232
233         set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, num_slots);
234
235         if (!num_slots)
236                 goto do_send;
237
238         spin_lock(&ls->ls_recover_lock);
239         if (ls->ls_num_slots != num_slots) {
240                 spin_unlock(&ls->ls_recover_lock);
241                 log_debug(ls, "receive_rcom_status num_slots %d to %d",
242                           num_slots, ls->ls_num_slots);
243                 rc->rc_result = 0;
244                 set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, 0);
245                 goto do_send;
246         }
247
248         dlm_slots_copy_out(ls, rc);
249         spin_unlock(&ls->ls_recover_lock);
250
251  do_send:
252         send_rcom(ls, mh, rc);
253 }
254
255 static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
256 {
257         spin_lock(&ls->ls_rcom_spin);
258         if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
259             rc_in->rc_id != ls->ls_rcom_seq) {
260                 log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
261                           rc_in->rc_type, rc_in->rc_header.h_nodeid,
262                           (unsigned long long)rc_in->rc_id,
263                           (unsigned long long)ls->ls_rcom_seq);
264                 goto out;
265         }
266         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
267         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
268         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
269         wake_up(&ls->ls_wait_general);
270  out:
271         spin_unlock(&ls->ls_rcom_spin);
272 }
273
274 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
275 {
276         struct dlm_rcom *rc;
277         struct dlm_mhandle *mh;
278         int error = 0;
279
280         ls->ls_recover_nodeid = nodeid;
281
282 retry:
283         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
284         if (error)
285                 goto out;
286         memcpy(rc->rc_buf, last_name, last_len);
287
288         allow_sync_reply(ls, &rc->rc_id);
289         memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
290
291         send_rcom(ls, mh, rc);
292
293         error = dlm_wait_function(ls, &rcom_response);
294         disallow_sync_reply(ls);
295         if (error == -ETIMEDOUT)
296                 goto retry;
297  out:
298         return error;
299 }
300
301 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
302 {
303         struct dlm_rcom *rc;
304         struct dlm_mhandle *mh;
305         int error, inlen, outlen, nodeid;
306
307         nodeid = rc_in->rc_header.h_nodeid;
308         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
309         outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
310
311         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
312         if (error)
313                 return;
314         rc->rc_id = rc_in->rc_id;
315         rc->rc_seq_reply = rc_in->rc_seq;
316
317         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
318                               nodeid);
319         send_rcom(ls, mh, rc);
320 }
321
322 int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
323 {
324         struct dlm_rcom *rc;
325         struct dlm_mhandle *mh;
326         struct dlm_ls *ls = r->res_ls;
327         int error;
328
329         error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
330                             &rc, &mh);
331         if (error)
332                 goto out;
333         memcpy(rc->rc_buf, r->res_name, r->res_length);
334         rc->rc_id = (unsigned long) r->res_id;
335
336         send_rcom(ls, mh, rc);
337  out:
338         return error;
339 }
340
341 static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
342 {
343         struct dlm_rcom *rc;
344         struct dlm_mhandle *mh;
345         int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
346         int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
347
348         error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
349         if (error)
350                 return;
351
352         /* Old code would send this special id to trigger a debug dump. */
353         if (rc_in->rc_id == 0xFFFFFFFF) {
354                 log_error(ls, "receive_rcom_lookup dump from %d", nodeid);
355                 dlm_dump_rsb_name(ls, rc_in->rc_buf, len);
356                 return;
357         }
358
359         error = dlm_master_lookup(ls, nodeid, rc_in->rc_buf, len,
360                                   DLM_LU_RECOVER_MASTER, &ret_nodeid, NULL);
361         if (error)
362                 ret_nodeid = error;
363         rc->rc_result = ret_nodeid;
364         rc->rc_id = rc_in->rc_id;
365         rc->rc_seq_reply = rc_in->rc_seq;
366
367         send_rcom(ls, mh, rc);
368 }
369
370 static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
371 {
372         dlm_recover_master_reply(ls, rc_in);
373 }
374
375 static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
376                            struct rcom_lock *rl)
377 {
378         memset(rl, 0, sizeof(*rl));
379
380         rl->rl_ownpid = cpu_to_le32(lkb->lkb_ownpid);
381         rl->rl_lkid = cpu_to_le32(lkb->lkb_id);
382         rl->rl_exflags = cpu_to_le32(lkb->lkb_exflags);
383         rl->rl_flags = cpu_to_le32(lkb->lkb_flags);
384         rl->rl_lvbseq = cpu_to_le32(lkb->lkb_lvbseq);
385         rl->rl_rqmode = lkb->lkb_rqmode;
386         rl->rl_grmode = lkb->lkb_grmode;
387         rl->rl_status = lkb->lkb_status;
388         rl->rl_wait_type = cpu_to_le16(lkb->lkb_wait_type);
389
390         if (lkb->lkb_bastfn)
391                 rl->rl_asts |= DLM_CB_BAST;
392         if (lkb->lkb_astfn)
393                 rl->rl_asts |= DLM_CB_CAST;
394
395         rl->rl_namelen = cpu_to_le16(r->res_length);
396         memcpy(rl->rl_name, r->res_name, r->res_length);
397
398         /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
399            If so, receive_rcom_lock_args() won't take this copy. */
400
401         if (lkb->lkb_lvbptr)
402                 memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
403 }
404
405 int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
406 {
407         struct dlm_ls *ls = r->res_ls;
408         struct dlm_rcom *rc;
409         struct dlm_mhandle *mh;
410         struct rcom_lock *rl;
411         int error, len = sizeof(struct rcom_lock);
412
413         if (lkb->lkb_lvbptr)
414                 len += ls->ls_lvblen;
415
416         error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
417         if (error)
418                 goto out;
419
420         rl = (struct rcom_lock *) rc->rc_buf;
421         pack_rcom_lock(r, lkb, rl);
422         rc->rc_id = (unsigned long) r;
423
424         send_rcom(ls, mh, rc);
425  out:
426         return error;
427 }
428
429 /* needs at least dlm_rcom + rcom_lock */
430 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
431 {
432         struct dlm_rcom *rc;
433         struct dlm_mhandle *mh;
434         int error, nodeid = rc_in->rc_header.h_nodeid;
435
436         dlm_recover_master_copy(ls, rc_in);
437
438         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
439                             sizeof(struct rcom_lock), &rc, &mh);
440         if (error)
441                 return;
442
443         /* We send back the same rcom_lock struct we received, but
444            dlm_recover_master_copy() has filled in rl_remid and rl_result */
445
446         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
447         rc->rc_id = rc_in->rc_id;
448         rc->rc_seq_reply = rc_in->rc_seq;
449
450         send_rcom(ls, mh, rc);
451 }
452
453 /* If the lockspace doesn't exist then still send a status message
454    back; it's possible that it just doesn't have its global_id yet. */
455
456 int dlm_send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
457 {
458         struct dlm_rcom *rc;
459         struct rcom_config *rf;
460         struct dlm_mhandle *mh;
461         char *mb;
462         int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
463
464         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_NOFS, &mb);
465         if (!mh)
466                 return -ENOBUFS;
467         memset(mb, 0, mb_len);
468
469         rc = (struct dlm_rcom *) mb;
470
471         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
472         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
473         rc->rc_header.h_nodeid = dlm_our_nodeid();
474         rc->rc_header.h_length = mb_len;
475         rc->rc_header.h_cmd = DLM_RCOM;
476
477         rc->rc_type = DLM_RCOM_STATUS_REPLY;
478         rc->rc_id = rc_in->rc_id;
479         rc->rc_seq_reply = rc_in->rc_seq;
480         rc->rc_result = -ESRCH;
481
482         rf = (struct rcom_config *) rc->rc_buf;
483         rf->rf_lvblen = cpu_to_le32(~0U);
484
485         dlm_rcom_out(rc);
486         dlm_lowcomms_commit_buffer(mh);
487
488         return 0;
489 }
490
491 /*
492  * Ignore messages for stage Y before we set
493  * recover_status bit for stage X:
494  *
495  * recover_status = 0
496  *
497  * dlm_recover_members()
498  * - send nothing
499  * - recv nothing
500  * - ignore NAMES, NAMES_REPLY
501  * - ignore LOOKUP, LOOKUP_REPLY
502  * - ignore LOCK, LOCK_REPLY
503  *
504  * recover_status |= NODES
505  *
506  * dlm_recover_members_wait()
507  *
508  * dlm_recover_directory()
509  * - send NAMES
510  * - recv NAMES_REPLY
511  * - ignore LOOKUP, LOOKUP_REPLY
512  * - ignore LOCK, LOCK_REPLY
513  *
514  * recover_status |= DIR
515  *
516  * dlm_recover_directory_wait()
517  *
518  * dlm_recover_masters()
519  * - send LOOKUP
520  * - recv LOOKUP_REPLY
521  *
522  * dlm_recover_locks()
523  * - send LOCKS
524  * - recv LOCKS_REPLY
525  *
526  * recover_status |= LOCKS
527  *
528  * dlm_recover_locks_wait()
529  *
530  * recover_status |= DONE
531  */
532
533 /* Called by dlm_recv; corresponds to dlm_receive_message() but special
534    recovery-only comms are sent through here. */
535
536 void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
537 {
538         int lock_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_lock);
539         int stop, reply = 0, names = 0, lookup = 0, lock = 0;
540         uint32_t status;
541         uint64_t seq;
542
543         switch (rc->rc_type) {
544         case DLM_RCOM_STATUS_REPLY:
545                 reply = 1;
546                 break;
547         case DLM_RCOM_NAMES:
548                 names = 1;
549                 break;
550         case DLM_RCOM_NAMES_REPLY:
551                 names = 1;
552                 reply = 1;
553                 break;
554         case DLM_RCOM_LOOKUP:
555                 lookup = 1;
556                 break;
557         case DLM_RCOM_LOOKUP_REPLY:
558                 lookup = 1;
559                 reply = 1;
560                 break;
561         case DLM_RCOM_LOCK:
562                 lock = 1;
563                 break;
564         case DLM_RCOM_LOCK_REPLY:
565                 lock = 1;
566                 reply = 1;
567                 break;
568         };
569
570         spin_lock(&ls->ls_recover_lock);
571         status = ls->ls_recover_status;
572         stop = test_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
573         seq = ls->ls_recover_seq;
574         spin_unlock(&ls->ls_recover_lock);
575
576         if (stop && (rc->rc_type != DLM_RCOM_STATUS))
577                 goto ignore;
578
579         if (reply && (rc->rc_seq_reply != seq))
580                 goto ignore;
581
582         if (!(status & DLM_RS_NODES) && (names || lookup || lock))
583                 goto ignore;
584
585         if (!(status & DLM_RS_DIR) && (lookup || lock))
586                 goto ignore;
587
588         switch (rc->rc_type) {
589         case DLM_RCOM_STATUS:
590                 receive_rcom_status(ls, rc);
591                 break;
592
593         case DLM_RCOM_NAMES:
594                 receive_rcom_names(ls, rc);
595                 break;
596
597         case DLM_RCOM_LOOKUP:
598                 receive_rcom_lookup(ls, rc);
599                 break;
600
601         case DLM_RCOM_LOCK:
602                 if (rc->rc_header.h_length < lock_size)
603                         goto Eshort;
604                 receive_rcom_lock(ls, rc);
605                 break;
606
607         case DLM_RCOM_STATUS_REPLY:
608                 receive_sync_reply(ls, rc);
609                 break;
610
611         case DLM_RCOM_NAMES_REPLY:
612                 receive_sync_reply(ls, rc);
613                 break;
614
615         case DLM_RCOM_LOOKUP_REPLY:
616                 receive_rcom_lookup_reply(ls, rc);
617                 break;
618
619         case DLM_RCOM_LOCK_REPLY:
620                 if (rc->rc_header.h_length < lock_size)
621                         goto Eshort;
622                 dlm_recover_process_copy(ls, rc);
623                 break;
624
625         default:
626                 log_error(ls, "receive_rcom bad type %d", rc->rc_type);
627         }
628         return;
629
630 ignore:
631         log_limit(ls, "dlm_receive_rcom ignore msg %d "
632                   "from %d %llu %llu recover seq %llu sts %x gen %u",
633                    rc->rc_type,
634                    nodeid,
635                    (unsigned long long)rc->rc_seq,
636                    (unsigned long long)rc->rc_seq_reply,
637                    (unsigned long long)seq,
638                    status, ls->ls_generation);
639         return;
640 Eshort:
641         log_error(ls, "recovery message %d from %d is too short",
642                   rc->rc_type, nodeid);
643 }
644