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 list_head *iter;
127 struct dlm_lock *tmplock=NULL;
128
129 assert_spin_locked(&res->spinlock);
130
131 mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
132 lock->ml.type, lock->ml.convert_type, type);
133
134 spin_lock(&lock->spinlock);
135
136 /* already converting? */
137 if (lock->ml.convert_type != LKM_IVMODE) {
138 mlog(ML_ERROR, "attempted to convert a lock with a lock "
139 "conversion pending\n");
140 status = DLM_DENIED;
141 goto unlock_exit;
142 }
143
144 /* must be on grant queue to convert */
145 if (!dlm_lock_on_list(&res->granted, lock)) {
146 mlog(ML_ERROR, "attempted to convert a lock not on grant "
147 "queue\n");
148 status = DLM_DENIED;
149 goto unlock_exit;
150 }
151
152 if (flags & LKM_VALBLK) {
153 switch (lock->ml.type) {
154 case LKM_EXMODE:
155 /* EX + LKM_VALBLK + convert == set lvb */
156 mlog(0, "will set lvb: converting %s->%s\n",
157 dlm_lock_mode_name(lock->ml.type),
158 dlm_lock_mode_name(type));
159 lock->lksb->flags |= DLM_LKSB_PUT_LVB;
160 break;
161 case LKM_PRMODE:
162 case LKM_NLMODE:
163 /* refetch if new level is not NL */
164 if (type > LKM_NLMODE) {
165 mlog(0, "will fetch new value into "
166 "lvb: converting %s->%s\n",
167 dlm_lock_mode_name(lock->ml.type),
168 dlm_lock_mode_name(type));
169 lock->lksb->flags |= DLM_LKSB_GET_LVB;
170 } else {
171 mlog(0, "will NOT fetch new value "
172 "into lvb: converting %s->%s\n",
173 dlm_lock_mode_name(lock->ml.type),
174 dlm_lock_mode_name(type));
175 flags &= ~(LKM_VALBLK);
176 }
177 break;
178 }
179 }
180
181
182 /* in-place downconvert? */
183 if (type <= lock->ml.type)
184 goto grant;
185
186 /* upconvert from here on */
187 status = DLM_NORMAL;
188 list_for_each(iter, &res->granted) {
189 tmplock = list_entry(iter, struct dlm_lock, list);
190 if (tmplock == lock)
191 continue;
192 if (!dlm_lock_compatible(tmplock->ml.type, type))
193 goto switch_queues;
194 }
195
196 list_for_each(iter, &res->converting) {
197 tmplock = list_entry(iter, struct dlm_lock, list);
198 if (!dlm_lock_compatible(tmplock->ml.type, type))
199 goto switch_queues;
200 /* existing conversion requests take precedence */
201 if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
202 goto switch_queues;
203 }
204
205 /* fall thru to grant */
206
207 grant:
208 mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
209 res->lockname.name, dlm_lock_mode_name(type));
210 /* immediately grant the new lock type */
211 lock->lksb->status = DLM_NORMAL;
212 if (lock->ml.node == dlm->node_num)
213 mlog(0, "doing in-place convert for nonlocal lock\n");
214 lock->ml.type = type;
215 if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
216 memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);
217
218 status = DLM_NORMAL;
219 *call_ast = 1;
220 goto unlock_exit;
221
222 switch_queues:
223 if (flags & LKM_NOQUEUE) {
224 mlog(0, "failed to convert NOQUEUE lock %.*s from "
225 "%d to %d...\n", res->lockname.len, res->lockname.name,
226 lock->ml.type, type);
227 status = DLM_NOTQUEUED;
228 goto unlock_exit;
229 }
230 mlog(0, "res %.*s, queueing...\n", res->lockname.len,
231 res->lockname.name);
232
233 lock->ml.convert_type = type;
234 /* do not alter lock refcount. switching lists. */
235 list_move_tail(&lock->list, &res->converting);
236
237 unlock_exit:
238 spin_unlock(&lock->spinlock);
239 if (status == DLM_DENIED) {
240 __dlm_print_one_lock_resource(res);
241 }
242 if (status == DLM_NORMAL)
243 *kick_thread = 1;
244 return status;
245 }
246
dlm_revert_pending_convert(struct dlm_lock_resource * res,struct dlm_lock * lock)247 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
248 struct dlm_lock *lock)
249 {
250 /* do not alter lock refcount. switching lists. */
251 list_move_tail(&lock->list, &res->granted);
252 lock->ml.convert_type = LKM_IVMODE;
253 lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
254 }
255
256 /* messages the master site to do lock conversion
257 * locking:
258 * caller needs: none
259 * taken: takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
260 * held on exit: none
261 * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
262 */
dlmconvert_remote(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type)263 enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
264 struct dlm_lock_resource *res,
265 struct dlm_lock *lock, int flags, int type)
266 {
267 enum dlm_status status;
268
269 mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
270 lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
271
272 spin_lock(&res->spinlock);
273 if (res->state & DLM_LOCK_RES_RECOVERING) {
274 mlog(0, "bailing out early since res is RECOVERING "
275 "on secondary queue\n");
276 /* __dlm_print_one_lock_resource(res); */
277 status = DLM_RECOVERING;
278 goto bail;
279 }
280 /* will exit this call with spinlock held */
281 __dlm_wait_on_lockres(res);
282
283 if (lock->ml.convert_type != LKM_IVMODE) {
284 __dlm_print_one_lock_resource(res);
285 mlog(ML_ERROR, "converting a remote lock that is already "
286 "converting! (cookie=%u:%llu, conv=%d)\n",
287 dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
288 dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
289 lock->ml.convert_type);
290 status = DLM_DENIED;
291 goto bail;
292 }
293 res->state |= DLM_LOCK_RES_IN_PROGRESS;
294 /* move lock to local convert queue */
295 /* do not alter lock refcount. switching lists. */
296 list_move_tail(&lock->list, &res->converting);
297 lock->convert_pending = 1;
298 lock->ml.convert_type = type;
299
300 if (flags & LKM_VALBLK) {
301 if (lock->ml.type == LKM_EXMODE) {
302 flags |= LKM_PUT_LVB;
303 lock->lksb->flags |= DLM_LKSB_PUT_LVB;
304 } else {
305 if (lock->ml.convert_type == LKM_NLMODE)
306 flags &= ~LKM_VALBLK;
307 else {
308 flags |= LKM_GET_LVB;
309 lock->lksb->flags |= DLM_LKSB_GET_LVB;
310 }
311 }
312 }
313 spin_unlock(&res->spinlock);
314
315 /* no locks held here.
316 * need to wait for a reply as to whether it got queued or not. */
317 status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);
318
319 spin_lock(&res->spinlock);
320 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
321 lock->convert_pending = 0;
322 /* if it failed, move it back to granted queue */
323 if (status != DLM_NORMAL) {
324 if (status != DLM_NOTQUEUED)
325 dlm_error(status);
326 dlm_revert_pending_convert(res, lock);
327 }
328 bail:
329 spin_unlock(&res->spinlock);
330
331 /* TODO: should this be a wake_one? */
332 /* wake up any IN_PROGRESS waiters */
333 wake_up(&res->wq);
334
335 return status;
336 }
337
338 /* sends DLM_CONVERT_LOCK_MSG to master site
339 * locking:
340 * caller needs: none
341 * taken: none
342 * held on exit: none
343 * returns: DLM_NOLOCKMGR, status from remote node
344 */
dlm_send_remote_convert_request(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags,int type)345 static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
346 struct dlm_lock_resource *res,
347 struct dlm_lock *lock, int flags, int type)
348 {
349 struct dlm_convert_lock convert;
350 int tmpret;
351 enum dlm_status ret;
352 int status = 0;
353 struct kvec vec[2];
354 size_t veclen = 1;
355
356 mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
357
358 memset(&convert, 0, sizeof(struct dlm_convert_lock));
359 convert.node_idx = dlm->node_num;
360 convert.requested_type = type;
361 convert.cookie = lock->ml.cookie;
362 convert.namelen = res->lockname.len;
363 convert.flags = cpu_to_be32(flags);
364 memcpy(convert.name, res->lockname.name, convert.namelen);
365
366 vec[0].iov_len = sizeof(struct dlm_convert_lock);
367 vec[0].iov_base = &convert;
368
369 if (flags & LKM_PUT_LVB) {
370 /* extra data to send if we are updating lvb */
371 vec[1].iov_len = DLM_LVB_LEN;
372 vec[1].iov_base = lock->lksb->lvb;
373 veclen++;
374 }
375
376 tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
377 vec, veclen, res->owner, &status);
378 if (tmpret >= 0) {
379 // successfully sent and received
380 ret = status; // this is already a dlm_status
381 if (ret == DLM_RECOVERING) {
382 mlog(0, "node %u returned DLM_RECOVERING from convert "
383 "message!\n", res->owner);
384 } else if (ret == DLM_MIGRATING) {
385 mlog(0, "node %u returned DLM_MIGRATING from convert "
386 "message!\n", res->owner);
387 } else if (ret == DLM_FORWARD) {
388 mlog(0, "node %u returned DLM_FORWARD from convert "
389 "message!\n", res->owner);
390 } else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
391 dlm_error(ret);
392 } else {
393 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
394 "node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
395 res->owner);
396 if (dlm_is_host_down(tmpret)) {
397 /* instead of logging the same network error over
398 * and over, sleep here and wait for the heartbeat
399 * to notice the node is dead. times out after 5s. */
400 dlm_wait_for_node_death(dlm, res->owner,
401 DLM_NODE_DEATH_WAIT_MAX);
402 ret = DLM_RECOVERING;
403 mlog(0, "node %u died so returning DLM_RECOVERING "
404 "from convert message!\n", res->owner);
405 } else {
406 ret = dlm_err_to_dlm_status(tmpret);
407 }
408 }
409
410 return ret;
411 }
412
413 /* handler for DLM_CONVERT_LOCK_MSG on master site
414 * locking:
415 * caller needs: none
416 * taken: takes and drop res->spinlock
417 * held on exit: none
418 * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
419 * status from __dlmconvert_master
420 */
dlm_convert_lock_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)421 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
422 void **ret_data)
423 {
424 struct dlm_ctxt *dlm = data;
425 struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf;
426 struct dlm_lock_resource *res = NULL;
427 struct list_head *iter;
428 struct dlm_lock *lock = NULL;
429 struct dlm_lockstatus *lksb;
430 enum dlm_status status = DLM_NORMAL;
431 u32 flags;
432 int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;
433
434 if (!dlm_grab(dlm)) {
435 dlm_error(DLM_REJECTED);
436 return DLM_REJECTED;
437 }
438
439 mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
440 "Domain %s not fully joined!\n", dlm->name);
441
442 if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
443 status = DLM_IVBUFLEN;
444 dlm_error(status);
445 goto leave;
446 }
447
448 flags = be32_to_cpu(cnv->flags);
449
450 if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) ==
451 (LKM_PUT_LVB|LKM_GET_LVB)) {
452 mlog(ML_ERROR, "both PUT and GET lvb specified\n");
453 status = DLM_BADARGS;
454 goto leave;
455 }
456
457 mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
458 (flags & LKM_GET_LVB ? "get lvb" : "none"));
459
460 status = DLM_IVLOCKID;
461 res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
462 if (!res) {
463 dlm_error(status);
464 goto leave;
465 }
466
467 spin_lock(&res->spinlock);
468 status = __dlm_lockres_state_to_status(res);
469 if (status != DLM_NORMAL) {
470 spin_unlock(&res->spinlock);
471 dlm_error(status);
472 goto leave;
473 }
474 list_for_each(iter, &res->granted) {
475 lock = list_entry(iter, struct dlm_lock, list);
476 if (lock->ml.cookie == cnv->cookie &&
477 lock->ml.node == cnv->node_idx) {
478 dlm_lock_get(lock);
479 break;
480 }
481 lock = NULL;
482 }
483 spin_unlock(&res->spinlock);
484 if (!lock) {
485 status = DLM_IVLOCKID;
486 mlog(ML_ERROR, "did not find lock to convert on grant queue! "
487 "cookie=%u:%llu\n",
488 dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
489 dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
490 dlm_print_one_lock_resource(res);
491 goto leave;
492 }
493
494 /* found the lock */
495 lksb = lock->lksb;
496
497 /* see if caller needed to get/put lvb */
498 if (flags & LKM_PUT_LVB) {
499 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
500 lksb->flags |= DLM_LKSB_PUT_LVB;
501 memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
502 } else if (flags & LKM_GET_LVB) {
503 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
504 lksb->flags |= DLM_LKSB_GET_LVB;
505 }
506
507 spin_lock(&res->spinlock);
508 status = __dlm_lockres_state_to_status(res);
509 if (status == DLM_NORMAL) {
510 __dlm_lockres_reserve_ast(res);
511 ast_reserved = 1;
512 res->state |= DLM_LOCK_RES_IN_PROGRESS;
513 status = __dlmconvert_master(dlm, res, lock, flags,
514 cnv->requested_type,
515 &call_ast, &kick_thread);
516 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
517 wake = 1;
518 }
519 spin_unlock(&res->spinlock);
520 if (wake)
521 wake_up(&res->wq);
522
523 if (status != DLM_NORMAL) {
524 if (status != DLM_NOTQUEUED)
525 dlm_error(status);
526 lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
527 }
528
529 leave:
530 if (lock)
531 dlm_lock_put(lock);
532
533 /* either queue the ast or release it, if reserved */
534 if (call_ast)
535 dlm_queue_ast(dlm, lock);
536 else if (ast_reserved)
537 dlm_lockres_release_ast(dlm, res);
538
539 if (kick_thread)
540 dlm_kick_thread(dlm, res);
541
542 if (res)
543 dlm_lockres_put(res);
544
545 dlm_put(dlm);
546
547 return status;
548 }
549