1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmconvert.c
5 *
6 * underlying calls for lock conversion
7 *
8 * Copyright (C) 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 *
25 */
26
27
28 #include <linux/module.h>
29 #include <linux/fs.h>
30 #include <linux/types.h>
31 #include <linux/highmem.h>
32 #include <linux/init.h>
33 #include <linux/sysctl.h>
34 #include <linux/random.h>
35 #include <linux/blkdev.h>
36 #include <linux/socket.h>
37 #include <linux/inet.h>
38 #include <linux/spinlock.h>
39
40
41 #include "cluster/heartbeat.h"
42 #include "cluster/nodemanager.h"
43 #include "cluster/tcp.h"
44
45 #include "dlmapi.h"
46 #include "dlmcommon.h"
47
48 #include "dlmconvert.h"
49
50 #define MLOG_MASK_PREFIX ML_DLM
51 #include "cluster/masklog.h"
52
53 /* NOTE: __dlmconvert_master is the only function in here that
54 * needs a spinlock held on entry (res->spinlock) and it is the
55 * only one that holds a lock on exit (res->spinlock).
56 * All other functions in here need no locks and drop all of
57 * the locks that they acquire. */
58 static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
59 struct dlm_lock_resource *res,
60 struct dlm_lock *lock, int flags,
61 int type, int *call_ast,
62 int *kick_thread);
63 static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
64 struct dlm_lock_resource *res,
65 struct dlm_lock *lock, int flags, int type);
66
67 /*
68 * this is only called directly by dlmlock(), and only when the
69 * local node is the owner of the lockres
70 * locking:
71 * caller needs: none
72 * taken: takes and drops res->spinlock
73 * held on exit: none
74 * returns: see __dlmconvert_master
75 */
dlmconvert_master(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type)76 enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm,
77 struct dlm_lock_resource *res,
78 struct dlm_lock *lock, int flags, int type)
79 {
80 int call_ast = 0, kick_thread = 0;
81 enum dlm_status status;
82
83 spin_lock(&res->spinlock);
84 /* we are not in a network handler, this is fine */
85 __dlm_wait_on_lockres(res);
86 __dlm_lockres_reserve_ast(res);
87 res->state |= DLM_LOCK_RES_IN_PROGRESS;
88
89 status = __dlmconvert_master(dlm, res, lock, flags, type,
90 &call_ast, &kick_thread);
91
92 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
93 spin_unlock(&res->spinlock);
94 wake_up(&res->wq);
95 if (status != DLM_NORMAL && status != DLM_NOTQUEUED)
96 dlm_error(status);
97
98 /* either queue the ast or release it */
99 if (call_ast)
100 dlm_queue_ast(dlm, lock);
101 else
102 dlm_lockres_release_ast(dlm, res);
103
104 if (kick_thread)
105 dlm_kick_thread(dlm, res);
106
107 return status;
108 }
109
110 /* performs lock conversion at the lockres master site
111 * locking:
112 * caller needs: res->spinlock
113 * taken: takes and drops lock->spinlock
114 * held on exit: res->spinlock
115 * returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED
116 * call_ast: whether ast should be called for this lock
117 * kick_thread: whether dlm_kick_thread should be called
118 */
__dlmconvert_master(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type,int * call_ast,int * kick_thread)119 static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
120 struct dlm_lock_resource *res,
121 struct dlm_lock *lock, int flags,
122 int type, int *call_ast,
123 int *kick_thread)
124 {
125 enum dlm_status status = DLM_NORMAL;
126 struct dlm_lock *tmplock=NULL;
127
128 assert_spin_locked(&res->spinlock);
129
130 mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
131 lock->ml.type, lock->ml.convert_type, type);
132
133 spin_lock(&lock->spinlock);
134
135 /* already converting? */
136 if (lock->ml.convert_type != LKM_IVMODE) {
137 mlog(ML_ERROR, "attempted to convert a lock with a lock "
138 "conversion pending\n");
139 status = DLM_DENIED;
140 goto unlock_exit;
141 }
142
143 /* must be on grant queue to convert */
144 if (!dlm_lock_on_list(&res->granted, lock)) {
145 mlog(ML_ERROR, "attempted to convert a lock not on grant "
146 "queue\n");
147 status = DLM_DENIED;
148 goto unlock_exit;
149 }
150
151 if (flags & LKM_VALBLK) {
152 switch (lock->ml.type) {
153 case LKM_EXMODE:
154 /* EX + LKM_VALBLK + convert == set lvb */
155 mlog(0, "will set lvb: converting %s->%s\n",
156 dlm_lock_mode_name(lock->ml.type),
157 dlm_lock_mode_name(type));
158 lock->lksb->flags |= DLM_LKSB_PUT_LVB;
159 break;
160 case LKM_PRMODE:
161 case LKM_NLMODE:
162 /* refetch if new level is not NL */
163 if (type > LKM_NLMODE) {
164 mlog(0, "will fetch new value into "
165 "lvb: converting %s->%s\n",
166 dlm_lock_mode_name(lock->ml.type),
167 dlm_lock_mode_name(type));
168 lock->lksb->flags |= DLM_LKSB_GET_LVB;
169 } else {
170 mlog(0, "will NOT fetch new value "
171 "into lvb: converting %s->%s\n",
172 dlm_lock_mode_name(lock->ml.type),
173 dlm_lock_mode_name(type));
174 flags &= ~(LKM_VALBLK);
175 }
176 break;
177 }
178 }
179
180
181 /* in-place downconvert? */
182 if (type <= lock->ml.type)
183 goto grant;
184
185 /* upconvert from here on */
186 status = DLM_NORMAL;
187 list_for_each_entry(tmplock, &res->granted, list) {
188 if (tmplock == lock)
189 continue;
190 if (!dlm_lock_compatible(tmplock->ml.type, type))
191 goto switch_queues;
192 }
193
194 list_for_each_entry(tmplock, &res->converting, list) {
195 if (!dlm_lock_compatible(tmplock->ml.type, type))
196 goto switch_queues;
197 /* existing conversion requests take precedence */
198 if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
199 goto switch_queues;
200 }
201
202 /* fall thru to grant */
203
204 grant:
205 mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
206 res->lockname.name, dlm_lock_mode_name(type));
207 /* immediately grant the new lock type */
208 lock->lksb->status = DLM_NORMAL;
209 if (lock->ml.node == dlm->node_num)
210 mlog(0, "doing in-place convert for nonlocal lock\n");
211 lock->ml.type = type;
212 if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
213 memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);
214
215 status = DLM_NORMAL;
216 *call_ast = 1;
217 goto unlock_exit;
218
219 switch_queues:
220 if (flags & LKM_NOQUEUE) {
221 mlog(0, "failed to convert NOQUEUE lock %.*s from "
222 "%d to %d...\n", res->lockname.len, res->lockname.name,
223 lock->ml.type, type);
224 status = DLM_NOTQUEUED;
225 goto unlock_exit;
226 }
227 mlog(0, "res %.*s, queueing...\n", res->lockname.len,
228 res->lockname.name);
229
230 lock->ml.convert_type = type;
231 /* do not alter lock refcount. switching lists. */
232 list_move_tail(&lock->list, &res->converting);
233
234 unlock_exit:
235 spin_unlock(&lock->spinlock);
236 if (status == DLM_DENIED) {
237 __dlm_print_one_lock_resource(res);
238 }
239 if (status == DLM_NORMAL)
240 *kick_thread = 1;
241 return status;
242 }
243
dlm_revert_pending_convert(struct dlm_lock_resource * res,struct dlm_lock * lock)244 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
245 struct dlm_lock *lock)
246 {
247 /* do not alter lock refcount. switching lists. */
248 list_move_tail(&lock->list, &res->granted);
249 lock->ml.convert_type = LKM_IVMODE;
250 lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
251 }
252
253 /* messages the master site to do lock conversion
254 * locking:
255 * caller needs: none
256 * taken: takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
257 * held on exit: none
258 * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
259 */
dlmconvert_remote(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type)260 enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
261 struct dlm_lock_resource *res,
262 struct dlm_lock *lock, int flags, int type)
263 {
264 enum dlm_status status;
265
266 mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
267 lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
268
269 spin_lock(&res->spinlock);
270 if (res->state & DLM_LOCK_RES_RECOVERING) {
271 mlog(0, "bailing out early since res is RECOVERING "
272 "on secondary queue\n");
273 /* __dlm_print_one_lock_resource(res); */
274 status = DLM_RECOVERING;
275 goto bail;
276 }
277 /* will exit this call with spinlock held */
278 __dlm_wait_on_lockres(res);
279
280 if (lock->ml.convert_type != LKM_IVMODE) {
281 __dlm_print_one_lock_resource(res);
282 mlog(ML_ERROR, "converting a remote lock that is already "
283 "converting! (cookie=%u:%llu, conv=%d)\n",
284 dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
285 dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
286 lock->ml.convert_type);
287 status = DLM_DENIED;
288 goto bail;
289 }
290
291 if (lock->ml.type == type && lock->ml.convert_type == LKM_IVMODE) {
292 mlog(0, "last convert request returned DLM_RECOVERING, but "
293 "owner has already queued and sent ast to me. res %.*s, "
294 "(cookie=%u:%llu, type=%d, conv=%d)\n",
295 res->lockname.len, res->lockname.name,
296 dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
297 dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
298 lock->ml.type, lock->ml.convert_type);
299 status = DLM_NORMAL;
300 goto bail;
301 }
302
303 res->state |= DLM_LOCK_RES_IN_PROGRESS;
304 /* move lock to local convert queue */
305 /* do not alter lock refcount. switching lists. */
306 list_move_tail(&lock->list, &res->converting);
307 lock->convert_pending = 1;
308 lock->ml.convert_type = type;
309
310 if (flags & LKM_VALBLK) {
311 if (lock->ml.type == LKM_EXMODE) {
312 flags |= LKM_PUT_LVB;
313 lock->lksb->flags |= DLM_LKSB_PUT_LVB;
314 } else {
315 if (lock->ml.convert_type == LKM_NLMODE)
316 flags &= ~LKM_VALBLK;
317 else {
318 flags |= LKM_GET_LVB;
319 lock->lksb->flags |= DLM_LKSB_GET_LVB;
320 }
321 }
322 }
323 spin_unlock(&res->spinlock);
324
325 /* no locks held here.
326 * need to wait for a reply as to whether it got queued or not. */
327 status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);
328
329 spin_lock(&res->spinlock);
330 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
331 /* if it failed, move it back to granted queue.
332 * if master returns DLM_NORMAL and then down before sending ast,
333 * it may have already been moved to granted queue, reset to
334 * DLM_RECOVERING and retry convert */
335 if (status != DLM_NORMAL) {
336 if (status != DLM_NOTQUEUED)
337 dlm_error(status);
338 dlm_revert_pending_convert(res, lock);
339 } else if (!lock->convert_pending) {
340 mlog(0, "%s: res %.*s, owner died and lock has been moved back "
341 "to granted list, retry convert.\n",
342 dlm->name, res->lockname.len, res->lockname.name);
343 status = DLM_RECOVERING;
344 }
345
346 lock->convert_pending = 0;
347 bail:
348 spin_unlock(&res->spinlock);
349
350 /* TODO: should this be a wake_one? */
351 /* wake up any IN_PROGRESS waiters */
352 wake_up(&res->wq);
353
354 return status;
355 }
356
357 /* sends DLM_CONVERT_LOCK_MSG to master site
358 * locking:
359 * caller needs: none
360 * taken: none
361 * held on exit: none
362 * returns: DLM_NOLOCKMGR, status from remote node
363 */
dlm_send_remote_convert_request(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type)364 static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
365 struct dlm_lock_resource *res,
366 struct dlm_lock *lock, int flags, int type)
367 {
368 struct dlm_convert_lock convert;
369 int tmpret;
370 enum dlm_status ret;
371 int status = 0;
372 struct kvec vec[2];
373 size_t veclen = 1;
374
375 mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
376
377 memset(&convert, 0, sizeof(struct dlm_convert_lock));
378 convert.node_idx = dlm->node_num;
379 convert.requested_type = type;
380 convert.cookie = lock->ml.cookie;
381 convert.namelen = res->lockname.len;
382 convert.flags = cpu_to_be32(flags);
383 memcpy(convert.name, res->lockname.name, convert.namelen);
384
385 vec[0].iov_len = sizeof(struct dlm_convert_lock);
386 vec[0].iov_base = &convert;
387
388 if (flags & LKM_PUT_LVB) {
389 /* extra data to send if we are updating lvb */
390 vec[1].iov_len = DLM_LVB_LEN;
391 vec[1].iov_base = lock->lksb->lvb;
392 veclen++;
393 }
394
395 tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
396 vec, veclen, res->owner, &status);
397 if (tmpret >= 0) {
398 // successfully sent and received
399 ret = status; // this is already a dlm_status
400 if (ret == DLM_RECOVERING) {
401 mlog(0, "node %u returned DLM_RECOVERING from convert "
402 "message!\n", res->owner);
403 } else if (ret == DLM_MIGRATING) {
404 mlog(0, "node %u returned DLM_MIGRATING from convert "
405 "message!\n", res->owner);
406 } else if (ret == DLM_FORWARD) {
407 mlog(0, "node %u returned DLM_FORWARD from convert "
408 "message!\n", res->owner);
409 } else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
410 dlm_error(ret);
411 } else {
412 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
413 "node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
414 res->owner);
415 if (dlm_is_host_down(tmpret)) {
416 /* instead of logging the same network error over
417 * and over, sleep here and wait for the heartbeat
418 * to notice the node is dead. times out after 5s. */
419 dlm_wait_for_node_death(dlm, res->owner,
420 DLM_NODE_DEATH_WAIT_MAX);
421 ret = DLM_RECOVERING;
422 mlog(0, "node %u died so returning DLM_RECOVERING "
423 "from convert message!\n", res->owner);
424 } else {
425 ret = dlm_err_to_dlm_status(tmpret);
426 }
427 }
428
429 return ret;
430 }
431
432 /* handler for DLM_CONVERT_LOCK_MSG on master site
433 * locking:
434 * caller needs: none
435 * taken: takes and drop res->spinlock
436 * held on exit: none
437 * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
438 * status from __dlmconvert_master
439 */
dlm_convert_lock_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)440 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
441 void **ret_data)
442 {
443 struct dlm_ctxt *dlm = data;
444 struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf;
445 struct dlm_lock_resource *res = NULL;
446 struct dlm_lock *lock = NULL;
447 struct dlm_lock *tmp_lock;
448 struct dlm_lockstatus *lksb;
449 enum dlm_status status = DLM_NORMAL;
450 u32 flags;
451 int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;
452
453 if (!dlm_grab(dlm)) {
454 dlm_error(DLM_REJECTED);
455 return DLM_REJECTED;
456 }
457
458 mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
459 "Domain %s not fully joined!\n", dlm->name);
460
461 if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
462 status = DLM_IVBUFLEN;
463 dlm_error(status);
464 goto leave;
465 }
466
467 flags = be32_to_cpu(cnv->flags);
468
469 if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) ==
470 (LKM_PUT_LVB|LKM_GET_LVB)) {
471 mlog(ML_ERROR, "both PUT and GET lvb specified\n");
472 status = DLM_BADARGS;
473 goto leave;
474 }
475
476 mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
477 (flags & LKM_GET_LVB ? "get lvb" : "none"));
478
479 status = DLM_IVLOCKID;
480 res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
481 if (!res) {
482 dlm_error(status);
483 goto leave;
484 }
485
486 spin_lock(&res->spinlock);
487 status = __dlm_lockres_state_to_status(res);
488 if (status != DLM_NORMAL) {
489 spin_unlock(&res->spinlock);
490 dlm_error(status);
491 goto leave;
492 }
493 list_for_each_entry(tmp_lock, &res->granted, list) {
494 if (tmp_lock->ml.cookie == cnv->cookie &&
495 tmp_lock->ml.node == cnv->node_idx) {
496 lock = tmp_lock;
497 dlm_lock_get(lock);
498 break;
499 }
500 }
501 spin_unlock(&res->spinlock);
502 if (!lock) {
503 status = DLM_IVLOCKID;
504 mlog(ML_ERROR, "did not find lock to convert on grant queue! "
505 "cookie=%u:%llu\n",
506 dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
507 dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
508 dlm_print_one_lock_resource(res);
509 goto leave;
510 }
511
512 /* found the lock */
513 lksb = lock->lksb;
514
515 /* see if caller needed to get/put lvb */
516 if (flags & LKM_PUT_LVB) {
517 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
518 lksb->flags |= DLM_LKSB_PUT_LVB;
519 memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
520 } else if (flags & LKM_GET_LVB) {
521 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
522 lksb->flags |= DLM_LKSB_GET_LVB;
523 }
524
525 spin_lock(&res->spinlock);
526 status = __dlm_lockres_state_to_status(res);
527 if (status == DLM_NORMAL) {
528 __dlm_lockres_reserve_ast(res);
529 ast_reserved = 1;
530 res->state |= DLM_LOCK_RES_IN_PROGRESS;
531 status = __dlmconvert_master(dlm, res, lock, flags,
532 cnv->requested_type,
533 &call_ast, &kick_thread);
534 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
535 wake = 1;
536 }
537 spin_unlock(&res->spinlock);
538 if (wake)
539 wake_up(&res->wq);
540
541 if (status != DLM_NORMAL) {
542 if (status != DLM_NOTQUEUED)
543 dlm_error(status);
544 lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
545 }
546
547 leave:
548 if (lock)
549 dlm_lock_put(lock);
550
551 /* either queue the ast or release it, if reserved */
552 if (call_ast)
553 dlm_queue_ast(dlm, lock);
554 else if (ast_reserved)
555 dlm_lockres_release_ast(dlm, res);
556
557 if (kick_thread)
558 dlm_kick_thread(dlm, res);
559
560 if (res)
561 dlm_lockres_put(res);
562
563 dlm_put(dlm);
564
565 return status;
566 }
567