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1/******************************************************************************
2*******************************************************************************
3**
4** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
5**
6** This copyrighted material is made available to anyone wishing to use,
7** modify, copy, or redistribute it subject to the terms and conditions
8** of the GNU General Public License v.2.
9**
10*******************************************************************************
11******************************************************************************/
12
13/* Central locking logic has four stages:
14
15 dlm_lock()
16 dlm_unlock()
17
18 request_lock(ls, lkb)
19 convert_lock(ls, lkb)
20 unlock_lock(ls, lkb)
21 cancel_lock(ls, lkb)
22
23 _request_lock(r, lkb)
24 _convert_lock(r, lkb)
25 _unlock_lock(r, lkb)
26 _cancel_lock(r, lkb)
27
28 do_request(r, lkb)
29 do_convert(r, lkb)
30 do_unlock(r, lkb)
31 do_cancel(r, lkb)
32
33 Stage 1 (lock, unlock) is mainly about checking input args and
34 splitting into one of the four main operations:
35
36 dlm_lock = request_lock
37 dlm_lock+CONVERT = convert_lock
38 dlm_unlock = unlock_lock
39 dlm_unlock+CANCEL = cancel_lock
40
41 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
42 provided to the next stage.
43
44 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
45 When remote, it calls send_xxxx(), when local it calls do_xxxx().
46
47 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
48 given rsb and lkb and queues callbacks.
49
50 For remote operations, send_xxxx() results in the corresponding do_xxxx()
51 function being executed on the remote node. The connecting send/receive
52 calls on local (L) and remote (R) nodes:
53
54 L: send_xxxx() -> R: receive_xxxx()
55 R: do_xxxx()
56 L: receive_xxxx_reply() <- R: send_xxxx_reply()
57*/
58#include <linux/types.h>
59#include <linux/slab.h>
60#include "dlm_internal.h"
61#include <linux/dlm_device.h>
62#include "memory.h"
63#include "lowcomms.h"
64#include "requestqueue.h"
65#include "util.h"
66#include "dir.h"
67#include "member.h"
68#include "lockspace.h"
69#include "ast.h"
70#include "lock.h"
71#include "rcom.h"
72#include "recover.h"
73#include "lvb_table.h"
74#include "user.h"
75#include "config.h"
76
77static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
78static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
82static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
83static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
84static int send_remove(struct dlm_rsb *r);
85static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
86static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
87static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
88 struct dlm_message *ms);
89static int receive_extralen(struct dlm_message *ms);
90static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
91static void del_timeout(struct dlm_lkb *lkb);
92
93/*
94 * Lock compatibilty matrix - thanks Steve
95 * UN = Unlocked state. Not really a state, used as a flag
96 * PD = Padding. Used to make the matrix a nice power of two in size
97 * Other states are the same as the VMS DLM.
98 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
99 */
100
101static const int __dlm_compat_matrix[8][8] = {
102 /* UN NL CR CW PR PW EX PD */
103 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
104 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
105 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
106 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
107 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
108 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
109 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
110 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
111};
112
113/*
114 * This defines the direction of transfer of LVB data.
115 * Granted mode is the row; requested mode is the column.
116 * Usage: matrix[grmode+1][rqmode+1]
117 * 1 = LVB is returned to the caller
118 * 0 = LVB is written to the resource
119 * -1 = nothing happens to the LVB
120 */
121
122const int dlm_lvb_operations[8][8] = {
123 /* UN NL CR CW PR PW EX PD*/
124 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
125 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
126 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
127 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
128 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
129 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
130 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
131 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
132};
133
134#define modes_compat(gr, rq) \
135 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
136
137int dlm_modes_compat(int mode1, int mode2)
138{
139 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
140}
141
142/*
143 * Compatibility matrix for conversions with QUECVT set.
144 * Granted mode is the row; requested mode is the column.
145 * Usage: matrix[grmode+1][rqmode+1]
146 */
147
148static const int __quecvt_compat_matrix[8][8] = {
149 /* UN NL CR CW PR PW EX PD */
150 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
151 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
152 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
153 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
154 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
155 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
156 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
157 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
158};
159
160void dlm_print_lkb(struct dlm_lkb *lkb)
161{
162 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n"
163 " status %d rqmode %d grmode %d wait_type %d\n",
164 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
165 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
166 lkb->lkb_grmode, lkb->lkb_wait_type);
167}
168
169static void dlm_print_rsb(struct dlm_rsb *r)
170{
171 printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n",
172 r->res_nodeid, r->res_flags, r->res_first_lkid,
173 r->res_recover_locks_count, r->res_name);
174}
175
176void dlm_dump_rsb(struct dlm_rsb *r)
177{
178 struct dlm_lkb *lkb;
179
180 dlm_print_rsb(r);
181
182 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
183 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
184 printk(KERN_ERR "rsb lookup list\n");
185 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
186 dlm_print_lkb(lkb);
187 printk(KERN_ERR "rsb grant queue:\n");
188 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
189 dlm_print_lkb(lkb);
190 printk(KERN_ERR "rsb convert queue:\n");
191 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
192 dlm_print_lkb(lkb);
193 printk(KERN_ERR "rsb wait queue:\n");
194 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
195 dlm_print_lkb(lkb);
196}
197
198/* Threads cannot use the lockspace while it's being recovered */
199
200static inline void dlm_lock_recovery(struct dlm_ls *ls)
201{
202 down_read(&ls->ls_in_recovery);
203}
204
205void dlm_unlock_recovery(struct dlm_ls *ls)
206{
207 up_read(&ls->ls_in_recovery);
208}
209
210int dlm_lock_recovery_try(struct dlm_ls *ls)
211{
212 return down_read_trylock(&ls->ls_in_recovery);
213}
214
215static inline int can_be_queued(struct dlm_lkb *lkb)
216{
217 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
218}
219
220static inline int force_blocking_asts(struct dlm_lkb *lkb)
221{
222 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
223}
224
225static inline int is_demoted(struct dlm_lkb *lkb)
226{
227 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
228}
229
230static inline int is_altmode(struct dlm_lkb *lkb)
231{
232 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
233}
234
235static inline int is_granted(struct dlm_lkb *lkb)
236{
237 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
238}
239
240static inline int is_remote(struct dlm_rsb *r)
241{
242 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
243 return !!r->res_nodeid;
244}
245
246static inline int is_process_copy(struct dlm_lkb *lkb)
247{
248 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
249}
250
251static inline int is_master_copy(struct dlm_lkb *lkb)
252{
253 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
254 DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb););
255 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
256}
257
258static inline int middle_conversion(struct dlm_lkb *lkb)
259{
260 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
261 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
262 return 1;
263 return 0;
264}
265
266static inline int down_conversion(struct dlm_lkb *lkb)
267{
268 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
269}
270
271static inline int is_overlap_unlock(struct dlm_lkb *lkb)
272{
273 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
274}
275
276static inline int is_overlap_cancel(struct dlm_lkb *lkb)
277{
278 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
279}
280
281static inline int is_overlap(struct dlm_lkb *lkb)
282{
283 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
284 DLM_IFL_OVERLAP_CANCEL));
285}
286
287static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
288{
289 if (is_master_copy(lkb))
290 return;
291
292 del_timeout(lkb);
293
294 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
295
296 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
297 timeout caused the cancel then return -ETIMEDOUT */
298 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
299 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
300 rv = -ETIMEDOUT;
301 }
302
303 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
304 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
305 rv = -EDEADLK;
306 }
307
308 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
309}
310
311static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
312{
313 queue_cast(r, lkb,
314 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
315}
316
317static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
318{
319 if (is_master_copy(lkb)) {
320 send_bast(r, lkb, rqmode);
321 } else {
322 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
323 }
324}
325
326/*
327 * Basic operations on rsb's and lkb's
328 */
329
330static int pre_rsb_struct(struct dlm_ls *ls)
331{
332 struct dlm_rsb *r1, *r2;
333 int count = 0;
334
335 spin_lock(&ls->ls_new_rsb_spin);
336 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
337 spin_unlock(&ls->ls_new_rsb_spin);
338 return 0;
339 }
340 spin_unlock(&ls->ls_new_rsb_spin);
341
342 r1 = dlm_allocate_rsb(ls);
343 r2 = dlm_allocate_rsb(ls);
344
345 spin_lock(&ls->ls_new_rsb_spin);
346 if (r1) {
347 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
348 ls->ls_new_rsb_count++;
349 }
350 if (r2) {
351 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
352 ls->ls_new_rsb_count++;
353 }
354 count = ls->ls_new_rsb_count;
355 spin_unlock(&ls->ls_new_rsb_spin);
356
357 if (!count)
358 return -ENOMEM;
359 return 0;
360}
361
362/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
363 unlock any spinlocks, go back and call pre_rsb_struct again.
364 Otherwise, take an rsb off the list and return it. */
365
366static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
367 struct dlm_rsb **r_ret)
368{
369 struct dlm_rsb *r;
370 int count;
371
372 spin_lock(&ls->ls_new_rsb_spin);
373 if (list_empty(&ls->ls_new_rsb)) {
374 count = ls->ls_new_rsb_count;
375 spin_unlock(&ls->ls_new_rsb_spin);
376 log_debug(ls, "find_rsb retry %d %d %s",
377 count, dlm_config.ci_new_rsb_count, name);
378 return -EAGAIN;
379 }
380
381 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
382 list_del(&r->res_hashchain);
383 ls->ls_new_rsb_count--;
384 spin_unlock(&ls->ls_new_rsb_spin);
385
386 r->res_ls = ls;
387 r->res_length = len;
388 memcpy(r->res_name, name, len);
389 mutex_init(&r->res_mutex);
390
391 INIT_LIST_HEAD(&r->res_hashchain);
392 INIT_LIST_HEAD(&r->res_lookup);
393 INIT_LIST_HEAD(&r->res_grantqueue);
394 INIT_LIST_HEAD(&r->res_convertqueue);
395 INIT_LIST_HEAD(&r->res_waitqueue);
396 INIT_LIST_HEAD(&r->res_root_list);
397 INIT_LIST_HEAD(&r->res_recover_list);
398
399 *r_ret = r;
400 return 0;
401}
402
403static int search_rsb_list(struct list_head *head, char *name, int len,
404 unsigned int flags, struct dlm_rsb **r_ret)
405{
406 struct dlm_rsb *r;
407 int error = 0;
408
409 list_for_each_entry(r, head, res_hashchain) {
410 if (len == r->res_length && !memcmp(name, r->res_name, len))
411 goto found;
412 }
413 *r_ret = NULL;
414 return -EBADR;
415
416 found:
417 if (r->res_nodeid && (flags & R_MASTER))
418 error = -ENOTBLK;
419 *r_ret = r;
420 return error;
421}
422
423static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b,
424 unsigned int flags, struct dlm_rsb **r_ret)
425{
426 struct dlm_rsb *r;
427 int error;
428
429 error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r);
430 if (!error) {
431 kref_get(&r->res_ref);
432 goto out;
433 }
434 error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
435 if (error)
436 goto out;
437
438 list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list);
439
440 if (dlm_no_directory(ls))
441 goto out;
442
443 if (r->res_nodeid == -1) {
444 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
445 r->res_first_lkid = 0;
446 } else if (r->res_nodeid > 0) {
447 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
448 r->res_first_lkid = 0;
449 } else {
450 DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r););
451 DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),);
452 }
453 out:
454 *r_ret = r;
455 return error;
456}
457
458/*
459 * Find rsb in rsbtbl and potentially create/add one
460 *
461 * Delaying the release of rsb's has a similar benefit to applications keeping
462 * NL locks on an rsb, but without the guarantee that the cached master value
463 * will still be valid when the rsb is reused. Apps aren't always smart enough
464 * to keep NL locks on an rsb that they may lock again shortly; this can lead
465 * to excessive master lookups and removals if we don't delay the release.
466 *
467 * Searching for an rsb means looking through both the normal list and toss
468 * list. When found on the toss list the rsb is moved to the normal list with
469 * ref count of 1; when found on normal list the ref count is incremented.
470 */
471
472static int find_rsb(struct dlm_ls *ls, char *name, int namelen,
473 unsigned int flags, struct dlm_rsb **r_ret)
474{
475 struct dlm_rsb *r = NULL;
476 uint32_t hash, bucket;
477 int error;
478
479 if (namelen > DLM_RESNAME_MAXLEN) {
480 error = -EINVAL;
481 goto out;
482 }
483
484 if (dlm_no_directory(ls))
485 flags |= R_CREATE;
486
487 hash = jhash(name, namelen, 0);
488 bucket = hash & (ls->ls_rsbtbl_size - 1);
489
490 retry:
491 if (flags & R_CREATE) {
492 error = pre_rsb_struct(ls);
493 if (error < 0)
494 goto out;
495 }
496
497 spin_lock(&ls->ls_rsbtbl[bucket].lock);
498
499 error = _search_rsb(ls, name, namelen, bucket, flags, &r);
500 if (!error)
501 goto out_unlock;
502
503 if (error == -EBADR && !(flags & R_CREATE))
504 goto out_unlock;
505
506 /* the rsb was found but wasn't a master copy */
507 if (error == -ENOTBLK)
508 goto out_unlock;
509
510 error = get_rsb_struct(ls, name, namelen, &r);
511 if (error == -EAGAIN) {
512 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
513 goto retry;
514 }
515 if (error)
516 goto out_unlock;
517
518 r->res_hash = hash;
519 r->res_bucket = bucket;
520 r->res_nodeid = -1;
521 kref_init(&r->res_ref);
522
523 /* With no directory, the master can be set immediately */
524 if (dlm_no_directory(ls)) {
525 int nodeid = dlm_dir_nodeid(r);
526 if (nodeid == dlm_our_nodeid())
527 nodeid = 0;
528 r->res_nodeid = nodeid;
529 }
530 list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list);
531 error = 0;
532 out_unlock:
533 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
534 out:
535 *r_ret = r;
536 return error;
537}
538
539/* This is only called to add a reference when the code already holds
540 a valid reference to the rsb, so there's no need for locking. */
541
542static inline void hold_rsb(struct dlm_rsb *r)
543{
544 kref_get(&r->res_ref);
545}
546
547void dlm_hold_rsb(struct dlm_rsb *r)
548{
549 hold_rsb(r);
550}
551
552static void toss_rsb(struct kref *kref)
553{
554 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
555 struct dlm_ls *ls = r->res_ls;
556
557 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
558 kref_init(&r->res_ref);
559 list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss);
560 r->res_toss_time = jiffies;
561 if (r->res_lvbptr) {
562 dlm_free_lvb(r->res_lvbptr);
563 r->res_lvbptr = NULL;
564 }
565}
566
567/* When all references to the rsb are gone it's transferred to
568 the tossed list for later disposal. */
569
570static void put_rsb(struct dlm_rsb *r)
571{
572 struct dlm_ls *ls = r->res_ls;
573 uint32_t bucket = r->res_bucket;
574
575 spin_lock(&ls->ls_rsbtbl[bucket].lock);
576 kref_put(&r->res_ref, toss_rsb);
577 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
578}
579
580void dlm_put_rsb(struct dlm_rsb *r)
581{
582 put_rsb(r);
583}
584
585/* See comment for unhold_lkb */
586
587static void unhold_rsb(struct dlm_rsb *r)
588{
589 int rv;
590 rv = kref_put(&r->res_ref, toss_rsb);
591 DLM_ASSERT(!rv, dlm_dump_rsb(r););
592}
593
594static void kill_rsb(struct kref *kref)
595{
596 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
597
598 /* All work is done after the return from kref_put() so we
599 can release the write_lock before the remove and free. */
600
601 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
602 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
603 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
604 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
605 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
606 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
607}
608
609/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
610 The rsb must exist as long as any lkb's for it do. */
611
612static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
613{
614 hold_rsb(r);
615 lkb->lkb_resource = r;
616}
617
618static void detach_lkb(struct dlm_lkb *lkb)
619{
620 if (lkb->lkb_resource) {
621 put_rsb(lkb->lkb_resource);
622 lkb->lkb_resource = NULL;
623 }
624}
625
626static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
627{
628 struct dlm_lkb *lkb;
629 int rv, id;
630
631 lkb = dlm_allocate_lkb(ls);
632 if (!lkb)
633 return -ENOMEM;
634
635 lkb->lkb_nodeid = -1;
636 lkb->lkb_grmode = DLM_LOCK_IV;
637 kref_init(&lkb->lkb_ref);
638 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
639 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
640 INIT_LIST_HEAD(&lkb->lkb_time_list);
641 INIT_LIST_HEAD(&lkb->lkb_cb_list);
642 mutex_init(&lkb->lkb_cb_mutex);
643 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
644
645 retry:
646 rv = idr_pre_get(&ls->ls_lkbidr, GFP_NOFS);
647 if (!rv)
648 return -ENOMEM;
649
650 spin_lock(&ls->ls_lkbidr_spin);
651 rv = idr_get_new_above(&ls->ls_lkbidr, lkb, 1, &id);
652 if (!rv)
653 lkb->lkb_id = id;
654 spin_unlock(&ls->ls_lkbidr_spin);
655
656 if (rv == -EAGAIN)
657 goto retry;
658
659 if (rv < 0) {
660 log_error(ls, "create_lkb idr error %d", rv);
661 return rv;
662 }
663
664 *lkb_ret = lkb;
665 return 0;
666}
667
668static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
669{
670 struct dlm_lkb *lkb;
671
672 spin_lock(&ls->ls_lkbidr_spin);
673 lkb = idr_find(&ls->ls_lkbidr, lkid);
674 if (lkb)
675 kref_get(&lkb->lkb_ref);
676 spin_unlock(&ls->ls_lkbidr_spin);
677
678 *lkb_ret = lkb;
679 return lkb ? 0 : -ENOENT;
680}
681
682static void kill_lkb(struct kref *kref)
683{
684 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
685
686 /* All work is done after the return from kref_put() so we
687 can release the write_lock before the detach_lkb */
688
689 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
690}
691
692/* __put_lkb() is used when an lkb may not have an rsb attached to
693 it so we need to provide the lockspace explicitly */
694
695static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
696{
697 uint32_t lkid = lkb->lkb_id;
698
699 spin_lock(&ls->ls_lkbidr_spin);
700 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
701 idr_remove(&ls->ls_lkbidr, lkid);
702 spin_unlock(&ls->ls_lkbidr_spin);
703
704 detach_lkb(lkb);
705
706 /* for local/process lkbs, lvbptr points to caller's lksb */
707 if (lkb->lkb_lvbptr && is_master_copy(lkb))
708 dlm_free_lvb(lkb->lkb_lvbptr);
709 dlm_free_lkb(lkb);
710 return 1;
711 } else {
712 spin_unlock(&ls->ls_lkbidr_spin);
713 return 0;
714 }
715}
716
717int dlm_put_lkb(struct dlm_lkb *lkb)
718{
719 struct dlm_ls *ls;
720
721 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
722 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
723
724 ls = lkb->lkb_resource->res_ls;
725 return __put_lkb(ls, lkb);
726}
727
728/* This is only called to add a reference when the code already holds
729 a valid reference to the lkb, so there's no need for locking. */
730
731static inline void hold_lkb(struct dlm_lkb *lkb)
732{
733 kref_get(&lkb->lkb_ref);
734}
735
736/* This is called when we need to remove a reference and are certain
737 it's not the last ref. e.g. del_lkb is always called between a
738 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
739 put_lkb would work fine, but would involve unnecessary locking */
740
741static inline void unhold_lkb(struct dlm_lkb *lkb)
742{
743 int rv;
744 rv = kref_put(&lkb->lkb_ref, kill_lkb);
745 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
746}
747
748static void lkb_add_ordered(struct list_head *new, struct list_head *head,
749 int mode)
750{
751 struct dlm_lkb *lkb = NULL;
752
753 list_for_each_entry(lkb, head, lkb_statequeue)
754 if (lkb->lkb_rqmode < mode)
755 break;
756
757 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
758}
759
760/* add/remove lkb to rsb's grant/convert/wait queue */
761
762static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
763{
764 kref_get(&lkb->lkb_ref);
765
766 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
767
768 lkb->lkb_timestamp = ktime_get();
769
770 lkb->lkb_status = status;
771
772 switch (status) {
773 case DLM_LKSTS_WAITING:
774 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
775 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
776 else
777 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
778 break;
779 case DLM_LKSTS_GRANTED:
780 /* convention says granted locks kept in order of grmode */
781 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
782 lkb->lkb_grmode);
783 break;
784 case DLM_LKSTS_CONVERT:
785 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
786 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
787 else
788 list_add_tail(&lkb->lkb_statequeue,
789 &r->res_convertqueue);
790 break;
791 default:
792 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
793 }
794}
795
796static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
797{
798 lkb->lkb_status = 0;
799 list_del(&lkb->lkb_statequeue);
800 unhold_lkb(lkb);
801}
802
803static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
804{
805 hold_lkb(lkb);
806 del_lkb(r, lkb);
807 add_lkb(r, lkb, sts);
808 unhold_lkb(lkb);
809}
810
811static int msg_reply_type(int mstype)
812{
813 switch (mstype) {
814 case DLM_MSG_REQUEST:
815 return DLM_MSG_REQUEST_REPLY;
816 case DLM_MSG_CONVERT:
817 return DLM_MSG_CONVERT_REPLY;
818 case DLM_MSG_UNLOCK:
819 return DLM_MSG_UNLOCK_REPLY;
820 case DLM_MSG_CANCEL:
821 return DLM_MSG_CANCEL_REPLY;
822 case DLM_MSG_LOOKUP:
823 return DLM_MSG_LOOKUP_REPLY;
824 }
825 return -1;
826}
827
828static int nodeid_warned(int nodeid, int num_nodes, int *warned)
829{
830 int i;
831
832 for (i = 0; i < num_nodes; i++) {
833 if (!warned[i]) {
834 warned[i] = nodeid;
835 return 0;
836 }
837 if (warned[i] == nodeid)
838 return 1;
839 }
840 return 0;
841}
842
843void dlm_scan_waiters(struct dlm_ls *ls)
844{
845 struct dlm_lkb *lkb;
846 ktime_t zero = ktime_set(0, 0);
847 s64 us;
848 s64 debug_maxus = 0;
849 u32 debug_scanned = 0;
850 u32 debug_expired = 0;
851 int num_nodes = 0;
852 int *warned = NULL;
853
854 if (!dlm_config.ci_waitwarn_us)
855 return;
856
857 mutex_lock(&ls->ls_waiters_mutex);
858
859 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
860 if (ktime_equal(lkb->lkb_wait_time, zero))
861 continue;
862
863 debug_scanned++;
864
865 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
866
867 if (us < dlm_config.ci_waitwarn_us)
868 continue;
869
870 lkb->lkb_wait_time = zero;
871
872 debug_expired++;
873 if (us > debug_maxus)
874 debug_maxus = us;
875
876 if (!num_nodes) {
877 num_nodes = ls->ls_num_nodes;
878 warned = kzalloc(num_nodes * sizeof(int), GFP_KERNEL);
879 }
880 if (!warned)
881 continue;
882 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
883 continue;
884
885 log_error(ls, "waitwarn %x %lld %d us check connection to "
886 "node %d", lkb->lkb_id, (long long)us,
887 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
888 }
889 mutex_unlock(&ls->ls_waiters_mutex);
890 kfree(warned);
891
892 if (debug_expired)
893 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
894 debug_scanned, debug_expired,
895 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
896}
897
898/* add/remove lkb from global waiters list of lkb's waiting for
899 a reply from a remote node */
900
901static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
902{
903 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
904 int error = 0;
905
906 mutex_lock(&ls->ls_waiters_mutex);
907
908 if (is_overlap_unlock(lkb) ||
909 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
910 error = -EINVAL;
911 goto out;
912 }
913
914 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
915 switch (mstype) {
916 case DLM_MSG_UNLOCK:
917 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
918 break;
919 case DLM_MSG_CANCEL:
920 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
921 break;
922 default:
923 error = -EBUSY;
924 goto out;
925 }
926 lkb->lkb_wait_count++;
927 hold_lkb(lkb);
928
929 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
930 lkb->lkb_id, lkb->lkb_wait_type, mstype,
931 lkb->lkb_wait_count, lkb->lkb_flags);
932 goto out;
933 }
934
935 DLM_ASSERT(!lkb->lkb_wait_count,
936 dlm_print_lkb(lkb);
937 printk("wait_count %d\n", lkb->lkb_wait_count););
938
939 lkb->lkb_wait_count++;
940 lkb->lkb_wait_type = mstype;
941 lkb->lkb_wait_time = ktime_get();
942 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
943 hold_lkb(lkb);
944 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
945 out:
946 if (error)
947 log_error(ls, "addwait error %x %d flags %x %d %d %s",
948 lkb->lkb_id, error, lkb->lkb_flags, mstype,
949 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
950 mutex_unlock(&ls->ls_waiters_mutex);
951 return error;
952}
953
954/* We clear the RESEND flag because we might be taking an lkb off the waiters
955 list as part of process_requestqueue (e.g. a lookup that has an optimized
956 request reply on the requestqueue) between dlm_recover_waiters_pre() which
957 set RESEND and dlm_recover_waiters_post() */
958
959static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
960 struct dlm_message *ms)
961{
962 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
963 int overlap_done = 0;
964
965 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
966 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
967 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
968 overlap_done = 1;
969 goto out_del;
970 }
971
972 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
973 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
974 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
975 overlap_done = 1;
976 goto out_del;
977 }
978
979 /* Cancel state was preemptively cleared by a successful convert,
980 see next comment, nothing to do. */
981
982 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
983 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
984 log_debug(ls, "remwait %x cancel_reply wait_type %d",
985 lkb->lkb_id, lkb->lkb_wait_type);
986 return -1;
987 }
988
989 /* Remove for the convert reply, and premptively remove for the
990 cancel reply. A convert has been granted while there's still
991 an outstanding cancel on it (the cancel is moot and the result
992 in the cancel reply should be 0). We preempt the cancel reply
993 because the app gets the convert result and then can follow up
994 with another op, like convert. This subsequent op would see the
995 lingering state of the cancel and fail with -EBUSY. */
996
997 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
998 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
999 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1000 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1001 lkb->lkb_id);
1002 lkb->lkb_wait_type = 0;
1003 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1004 lkb->lkb_wait_count--;
1005 goto out_del;
1006 }
1007
1008 /* N.B. type of reply may not always correspond to type of original
1009 msg due to lookup->request optimization, verify others? */
1010
1011 if (lkb->lkb_wait_type) {
1012 lkb->lkb_wait_type = 0;
1013 goto out_del;
1014 }
1015
1016 log_error(ls, "remwait error %x reply %d flags %x no wait_type",
1017 lkb->lkb_id, mstype, lkb->lkb_flags);
1018 return -1;
1019
1020 out_del:
1021 /* the force-unlock/cancel has completed and we haven't recvd a reply
1022 to the op that was in progress prior to the unlock/cancel; we
1023 give up on any reply to the earlier op. FIXME: not sure when/how
1024 this would happen */
1025
1026 if (overlap_done && lkb->lkb_wait_type) {
1027 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
1028 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1029 lkb->lkb_wait_count--;
1030 lkb->lkb_wait_type = 0;
1031 }
1032
1033 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1034
1035 lkb->lkb_flags &= ~DLM_IFL_RESEND;
1036 lkb->lkb_wait_count--;
1037 if (!lkb->lkb_wait_count)
1038 list_del_init(&lkb->lkb_wait_reply);
1039 unhold_lkb(lkb);
1040 return 0;
1041}
1042
1043static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
1044{
1045 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1046 int error;
1047
1048 mutex_lock(&ls->ls_waiters_mutex);
1049 error = _remove_from_waiters(lkb, mstype, NULL);
1050 mutex_unlock(&ls->ls_waiters_mutex);
1051 return error;
1052}
1053
1054/* Handles situations where we might be processing a "fake" or "stub" reply in
1055 which we can't try to take waiters_mutex again. */
1056
1057static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1058{
1059 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1060 int error;
1061
1062 if (ms->m_flags != DLM_IFL_STUB_MS)
1063 mutex_lock(&ls->ls_waiters_mutex);
1064 error = _remove_from_waiters(lkb, ms->m_type, ms);
1065 if (ms->m_flags != DLM_IFL_STUB_MS)
1066 mutex_unlock(&ls->ls_waiters_mutex);
1067 return error;
1068}
1069
1070static void dir_remove(struct dlm_rsb *r)
1071{
1072 int to_nodeid;
1073
1074 if (dlm_no_directory(r->res_ls))
1075 return;
1076
1077 to_nodeid = dlm_dir_nodeid(r);
1078 if (to_nodeid != dlm_our_nodeid())
1079 send_remove(r);
1080 else
1081 dlm_dir_remove_entry(r->res_ls, to_nodeid,
1082 r->res_name, r->res_length);
1083}
1084
1085/* FIXME: shouldn't this be able to exit as soon as one non-due rsb is
1086 found since they are in order of newest to oldest? */
1087
1088static int shrink_bucket(struct dlm_ls *ls, int b)
1089{
1090 struct dlm_rsb *r;
1091 int count = 0, found;
1092
1093 for (;;) {
1094 found = 0;
1095 spin_lock(&ls->ls_rsbtbl[b].lock);
1096 list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss,
1097 res_hashchain) {
1098 if (!time_after_eq(jiffies, r->res_toss_time +
1099 dlm_config.ci_toss_secs * HZ))
1100 continue;
1101 found = 1;
1102 break;
1103 }
1104
1105 if (!found) {
1106 spin_unlock(&ls->ls_rsbtbl[b].lock);
1107 break;
1108 }
1109
1110 if (kref_put(&r->res_ref, kill_rsb)) {
1111 list_del(&r->res_hashchain);
1112 spin_unlock(&ls->ls_rsbtbl[b].lock);
1113
1114 if (is_master(r))
1115 dir_remove(r);
1116 dlm_free_rsb(r);
1117 count++;
1118 } else {
1119 spin_unlock(&ls->ls_rsbtbl[b].lock);
1120 log_error(ls, "tossed rsb in use %s", r->res_name);
1121 }
1122 }
1123
1124 return count;
1125}
1126
1127void dlm_scan_rsbs(struct dlm_ls *ls)
1128{
1129 int i;
1130
1131 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1132 shrink_bucket(ls, i);
1133 if (dlm_locking_stopped(ls))
1134 break;
1135 cond_resched();
1136 }
1137}
1138
1139static void add_timeout(struct dlm_lkb *lkb)
1140{
1141 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1142
1143 if (is_master_copy(lkb))
1144 return;
1145
1146 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1147 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1148 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1149 goto add_it;
1150 }
1151 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1152 goto add_it;
1153 return;
1154
1155 add_it:
1156 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1157 mutex_lock(&ls->ls_timeout_mutex);
1158 hold_lkb(lkb);
1159 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1160 mutex_unlock(&ls->ls_timeout_mutex);
1161}
1162
1163static void del_timeout(struct dlm_lkb *lkb)
1164{
1165 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1166
1167 mutex_lock(&ls->ls_timeout_mutex);
1168 if (!list_empty(&lkb->lkb_time_list)) {
1169 list_del_init(&lkb->lkb_time_list);
1170 unhold_lkb(lkb);
1171 }
1172 mutex_unlock(&ls->ls_timeout_mutex);
1173}
1174
1175/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1176 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1177 and then lock rsb because of lock ordering in add_timeout. We may need
1178 to specify some special timeout-related bits in the lkb that are just to
1179 be accessed under the timeout_mutex. */
1180
1181void dlm_scan_timeout(struct dlm_ls *ls)
1182{
1183 struct dlm_rsb *r;
1184 struct dlm_lkb *lkb;
1185 int do_cancel, do_warn;
1186 s64 wait_us;
1187
1188 for (;;) {
1189 if (dlm_locking_stopped(ls))
1190 break;
1191
1192 do_cancel = 0;
1193 do_warn = 0;
1194 mutex_lock(&ls->ls_timeout_mutex);
1195 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1196
1197 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1198 lkb->lkb_timestamp));
1199
1200 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
1201 wait_us >= (lkb->lkb_timeout_cs * 10000))
1202 do_cancel = 1;
1203
1204 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
1205 wait_us >= dlm_config.ci_timewarn_cs * 10000)
1206 do_warn = 1;
1207
1208 if (!do_cancel && !do_warn)
1209 continue;
1210 hold_lkb(lkb);
1211 break;
1212 }
1213 mutex_unlock(&ls->ls_timeout_mutex);
1214
1215 if (!do_cancel && !do_warn)
1216 break;
1217
1218 r = lkb->lkb_resource;
1219 hold_rsb(r);
1220 lock_rsb(r);
1221
1222 if (do_warn) {
1223 /* clear flag so we only warn once */
1224 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1225 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1226 del_timeout(lkb);
1227 dlm_timeout_warn(lkb);
1228 }
1229
1230 if (do_cancel) {
1231 log_debug(ls, "timeout cancel %x node %d %s",
1232 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1233 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1234 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1235 del_timeout(lkb);
1236 _cancel_lock(r, lkb);
1237 }
1238
1239 unlock_rsb(r);
1240 unhold_rsb(r);
1241 dlm_put_lkb(lkb);
1242 }
1243}
1244
1245/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1246 dlm_recoverd before checking/setting ls_recover_begin. */
1247
1248void dlm_adjust_timeouts(struct dlm_ls *ls)
1249{
1250 struct dlm_lkb *lkb;
1251 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
1252
1253 ls->ls_recover_begin = 0;
1254 mutex_lock(&ls->ls_timeout_mutex);
1255 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
1256 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
1257 mutex_unlock(&ls->ls_timeout_mutex);
1258
1259 if (!dlm_config.ci_waitwarn_us)
1260 return;
1261
1262 mutex_lock(&ls->ls_waiters_mutex);
1263 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1264 if (ktime_to_us(lkb->lkb_wait_time))
1265 lkb->lkb_wait_time = ktime_get();
1266 }
1267 mutex_unlock(&ls->ls_waiters_mutex);
1268}
1269
1270/* lkb is master or local copy */
1271
1272static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1273{
1274 int b, len = r->res_ls->ls_lvblen;
1275
1276 /* b=1 lvb returned to caller
1277 b=0 lvb written to rsb or invalidated
1278 b=-1 do nothing */
1279
1280 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1281
1282 if (b == 1) {
1283 if (!lkb->lkb_lvbptr)
1284 return;
1285
1286 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1287 return;
1288
1289 if (!r->res_lvbptr)
1290 return;
1291
1292 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1293 lkb->lkb_lvbseq = r->res_lvbseq;
1294
1295 } else if (b == 0) {
1296 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1297 rsb_set_flag(r, RSB_VALNOTVALID);
1298 return;
1299 }
1300
1301 if (!lkb->lkb_lvbptr)
1302 return;
1303
1304 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1305 return;
1306
1307 if (!r->res_lvbptr)
1308 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1309
1310 if (!r->res_lvbptr)
1311 return;
1312
1313 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1314 r->res_lvbseq++;
1315 lkb->lkb_lvbseq = r->res_lvbseq;
1316 rsb_clear_flag(r, RSB_VALNOTVALID);
1317 }
1318
1319 if (rsb_flag(r, RSB_VALNOTVALID))
1320 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1321}
1322
1323static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1324{
1325 if (lkb->lkb_grmode < DLM_LOCK_PW)
1326 return;
1327
1328 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1329 rsb_set_flag(r, RSB_VALNOTVALID);
1330 return;
1331 }
1332
1333 if (!lkb->lkb_lvbptr)
1334 return;
1335
1336 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1337 return;
1338
1339 if (!r->res_lvbptr)
1340 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1341
1342 if (!r->res_lvbptr)
1343 return;
1344
1345 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
1346 r->res_lvbseq++;
1347 rsb_clear_flag(r, RSB_VALNOTVALID);
1348}
1349
1350/* lkb is process copy (pc) */
1351
1352static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1353 struct dlm_message *ms)
1354{
1355 int b;
1356
1357 if (!lkb->lkb_lvbptr)
1358 return;
1359
1360 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1361 return;
1362
1363 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1364 if (b == 1) {
1365 int len = receive_extralen(ms);
1366 if (len > DLM_RESNAME_MAXLEN)
1367 len = DLM_RESNAME_MAXLEN;
1368 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
1369 lkb->lkb_lvbseq = ms->m_lvbseq;
1370 }
1371}
1372
1373/* Manipulate lkb's on rsb's convert/granted/waiting queues
1374 remove_lock -- used for unlock, removes lkb from granted
1375 revert_lock -- used for cancel, moves lkb from convert to granted
1376 grant_lock -- used for request and convert, adds lkb to granted or
1377 moves lkb from convert or waiting to granted
1378
1379 Each of these is used for master or local copy lkb's. There is
1380 also a _pc() variation used to make the corresponding change on
1381 a process copy (pc) lkb. */
1382
1383static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1384{
1385 del_lkb(r, lkb);
1386 lkb->lkb_grmode = DLM_LOCK_IV;
1387 /* this unhold undoes the original ref from create_lkb()
1388 so this leads to the lkb being freed */
1389 unhold_lkb(lkb);
1390}
1391
1392static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1393{
1394 set_lvb_unlock(r, lkb);
1395 _remove_lock(r, lkb);
1396}
1397
1398static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1399{
1400 _remove_lock(r, lkb);
1401}
1402
1403/* returns: 0 did nothing
1404 1 moved lock to granted
1405 -1 removed lock */
1406
1407static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1408{
1409 int rv = 0;
1410
1411 lkb->lkb_rqmode = DLM_LOCK_IV;
1412
1413 switch (lkb->lkb_status) {
1414 case DLM_LKSTS_GRANTED:
1415 break;
1416 case DLM_LKSTS_CONVERT:
1417 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1418 rv = 1;
1419 break;
1420 case DLM_LKSTS_WAITING:
1421 del_lkb(r, lkb);
1422 lkb->lkb_grmode = DLM_LOCK_IV;
1423 /* this unhold undoes the original ref from create_lkb()
1424 so this leads to the lkb being freed */
1425 unhold_lkb(lkb);
1426 rv = -1;
1427 break;
1428 default:
1429 log_print("invalid status for revert %d", lkb->lkb_status);
1430 }
1431 return rv;
1432}
1433
1434static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1435{
1436 return revert_lock(r, lkb);
1437}
1438
1439static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1440{
1441 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
1442 lkb->lkb_grmode = lkb->lkb_rqmode;
1443 if (lkb->lkb_status)
1444 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1445 else
1446 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
1447 }
1448
1449 lkb->lkb_rqmode = DLM_LOCK_IV;
1450}
1451
1452static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1453{
1454 set_lvb_lock(r, lkb);
1455 _grant_lock(r, lkb);
1456 lkb->lkb_highbast = 0;
1457}
1458
1459static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1460 struct dlm_message *ms)
1461{
1462 set_lvb_lock_pc(r, lkb, ms);
1463 _grant_lock(r, lkb);
1464}
1465
1466/* called by grant_pending_locks() which means an async grant message must
1467 be sent to the requesting node in addition to granting the lock if the
1468 lkb belongs to a remote node. */
1469
1470static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
1471{
1472 grant_lock(r, lkb);
1473 if (is_master_copy(lkb))
1474 send_grant(r, lkb);
1475 else
1476 queue_cast(r, lkb, 0);
1477}
1478
1479/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
1480 change the granted/requested modes. We're munging things accordingly in
1481 the process copy.
1482 CONVDEADLK: our grmode may have been forced down to NL to resolve a
1483 conversion deadlock
1484 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
1485 compatible with other granted locks */
1486
1487static void munge_demoted(struct dlm_lkb *lkb)
1488{
1489 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
1490 log_print("munge_demoted %x invalid modes gr %d rq %d",
1491 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
1492 return;
1493 }
1494
1495 lkb->lkb_grmode = DLM_LOCK_NL;
1496}
1497
1498static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
1499{
1500 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
1501 ms->m_type != DLM_MSG_GRANT) {
1502 log_print("munge_altmode %x invalid reply type %d",
1503 lkb->lkb_id, ms->m_type);
1504 return;
1505 }
1506
1507 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
1508 lkb->lkb_rqmode = DLM_LOCK_PR;
1509 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
1510 lkb->lkb_rqmode = DLM_LOCK_CW;
1511 else {
1512 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
1513 dlm_print_lkb(lkb);
1514 }
1515}
1516
1517static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
1518{
1519 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
1520 lkb_statequeue);
1521 if (lkb->lkb_id == first->lkb_id)
1522 return 1;
1523
1524 return 0;
1525}
1526
1527/* Check if the given lkb conflicts with another lkb on the queue. */
1528
1529static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
1530{
1531 struct dlm_lkb *this;
1532
1533 list_for_each_entry(this, head, lkb_statequeue) {
1534 if (this == lkb)
1535 continue;
1536 if (!modes_compat(this, lkb))
1537 return 1;
1538 }
1539 return 0;
1540}
1541
1542/*
1543 * "A conversion deadlock arises with a pair of lock requests in the converting
1544 * queue for one resource. The granted mode of each lock blocks the requested
1545 * mode of the other lock."
1546 *
1547 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
1548 * convert queue from being granted, then deadlk/demote lkb.
1549 *
1550 * Example:
1551 * Granted Queue: empty
1552 * Convert Queue: NL->EX (first lock)
1553 * PR->EX (second lock)
1554 *
1555 * The first lock can't be granted because of the granted mode of the second
1556 * lock and the second lock can't be granted because it's not first in the
1557 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
1558 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
1559 * flag set and return DEMOTED in the lksb flags.
1560 *
1561 * Originally, this function detected conv-deadlk in a more limited scope:
1562 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
1563 * - if lkb1 was the first entry in the queue (not just earlier), and was
1564 * blocked by the granted mode of lkb2, and there was nothing on the
1565 * granted queue preventing lkb1 from being granted immediately, i.e.
1566 * lkb2 was the only thing preventing lkb1 from being granted.
1567 *
1568 * That second condition meant we'd only say there was conv-deadlk if
1569 * resolving it (by demotion) would lead to the first lock on the convert
1570 * queue being granted right away. It allowed conversion deadlocks to exist
1571 * between locks on the convert queue while they couldn't be granted anyway.
1572 *
1573 * Now, we detect and take action on conversion deadlocks immediately when
1574 * they're created, even if they may not be immediately consequential. If
1575 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
1576 * mode that would prevent lkb1's conversion from being granted, we do a
1577 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
1578 * I think this means that the lkb_is_ahead condition below should always
1579 * be zero, i.e. there will never be conv-deadlk between two locks that are
1580 * both already on the convert queue.
1581 */
1582
1583static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
1584{
1585 struct dlm_lkb *lkb1;
1586 int lkb_is_ahead = 0;
1587
1588 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
1589 if (lkb1 == lkb2) {
1590 lkb_is_ahead = 1;
1591 continue;
1592 }
1593
1594 if (!lkb_is_ahead) {
1595 if (!modes_compat(lkb2, lkb1))
1596 return 1;
1597 } else {
1598 if (!modes_compat(lkb2, lkb1) &&
1599 !modes_compat(lkb1, lkb2))
1600 return 1;
1601 }
1602 }
1603 return 0;
1604}
1605
1606/*
1607 * Return 1 if the lock can be granted, 0 otherwise.
1608 * Also detect and resolve conversion deadlocks.
1609 *
1610 * lkb is the lock to be granted
1611 *
1612 * now is 1 if the function is being called in the context of the
1613 * immediate request, it is 0 if called later, after the lock has been
1614 * queued.
1615 *
1616 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
1617 */
1618
1619static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now)
1620{
1621 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
1622
1623 /*
1624 * 6-10: Version 5.4 introduced an option to address the phenomenon of
1625 * a new request for a NL mode lock being blocked.
1626 *
1627 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
1628 * request, then it would be granted. In essence, the use of this flag
1629 * tells the Lock Manager to expedite theis request by not considering
1630 * what may be in the CONVERTING or WAITING queues... As of this
1631 * writing, the EXPEDITE flag can be used only with new requests for NL
1632 * mode locks. This flag is not valid for conversion requests.
1633 *
1634 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
1635 * conversion or used with a non-NL requested mode. We also know an
1636 * EXPEDITE request is always granted immediately, so now must always
1637 * be 1. The full condition to grant an expedite request: (now &&
1638 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
1639 * therefore be shortened to just checking the flag.
1640 */
1641
1642 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
1643 return 1;
1644
1645 /*
1646 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
1647 * added to the remaining conditions.
1648 */
1649
1650 if (queue_conflict(&r->res_grantqueue, lkb))
1651 goto out;
1652
1653 /*
1654 * 6-3: By default, a conversion request is immediately granted if the
1655 * requested mode is compatible with the modes of all other granted
1656 * locks
1657 */
1658
1659 if (queue_conflict(&r->res_convertqueue, lkb))
1660 goto out;
1661
1662 /*
1663 * 6-5: But the default algorithm for deciding whether to grant or
1664 * queue conversion requests does not by itself guarantee that such
1665 * requests are serviced on a "first come first serve" basis. This, in
1666 * turn, can lead to a phenomenon known as "indefinate postponement".
1667 *
1668 * 6-7: This issue is dealt with by using the optional QUECVT flag with
1669 * the system service employed to request a lock conversion. This flag
1670 * forces certain conversion requests to be queued, even if they are
1671 * compatible with the granted modes of other locks on the same
1672 * resource. Thus, the use of this flag results in conversion requests
1673 * being ordered on a "first come first servce" basis.
1674 *
1675 * DCT: This condition is all about new conversions being able to occur
1676 * "in place" while the lock remains on the granted queue (assuming
1677 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
1678 * doesn't _have_ to go onto the convert queue where it's processed in
1679 * order. The "now" variable is necessary to distinguish converts
1680 * being received and processed for the first time now, because once a
1681 * convert is moved to the conversion queue the condition below applies
1682 * requiring fifo granting.
1683 */
1684
1685 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
1686 return 1;
1687
1688 /*
1689 * The NOORDER flag is set to avoid the standard vms rules on grant
1690 * order.
1691 */
1692
1693 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
1694 return 1;
1695
1696 /*
1697 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
1698 * granted until all other conversion requests ahead of it are granted
1699 * and/or canceled.
1700 */
1701
1702 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
1703 return 1;
1704
1705 /*
1706 * 6-4: By default, a new request is immediately granted only if all
1707 * three of the following conditions are satisfied when the request is
1708 * issued:
1709 * - The queue of ungranted conversion requests for the resource is
1710 * empty.
1711 * - The queue of ungranted new requests for the resource is empty.
1712 * - The mode of the new request is compatible with the most
1713 * restrictive mode of all granted locks on the resource.
1714 */
1715
1716 if (now && !conv && list_empty(&r->res_convertqueue) &&
1717 list_empty(&r->res_waitqueue))
1718 return 1;
1719
1720 /*
1721 * 6-4: Once a lock request is in the queue of ungranted new requests,
1722 * it cannot be granted until the queue of ungranted conversion
1723 * requests is empty, all ungranted new requests ahead of it are
1724 * granted and/or canceled, and it is compatible with the granted mode
1725 * of the most restrictive lock granted on the resource.
1726 */
1727
1728 if (!now && !conv && list_empty(&r->res_convertqueue) &&
1729 first_in_list(lkb, &r->res_waitqueue))
1730 return 1;
1731 out:
1732 return 0;
1733}
1734
1735static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
1736 int *err)
1737{
1738 int rv;
1739 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
1740 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
1741
1742 if (err)
1743 *err = 0;
1744
1745 rv = _can_be_granted(r, lkb, now);
1746 if (rv)
1747 goto out;
1748
1749 /*
1750 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
1751 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
1752 * cancels one of the locks.
1753 */
1754
1755 if (is_convert && can_be_queued(lkb) &&
1756 conversion_deadlock_detect(r, lkb)) {
1757 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
1758 lkb->lkb_grmode = DLM_LOCK_NL;
1759 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
1760 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1761 if (err)
1762 *err = -EDEADLK;
1763 else {
1764 log_print("can_be_granted deadlock %x now %d",
1765 lkb->lkb_id, now);
1766 dlm_dump_rsb(r);
1767 }
1768 }
1769 goto out;
1770 }
1771
1772 /*
1773 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
1774 * to grant a request in a mode other than the normal rqmode. It's a
1775 * simple way to provide a big optimization to applications that can
1776 * use them.
1777 */
1778
1779 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
1780 alt = DLM_LOCK_PR;
1781 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
1782 alt = DLM_LOCK_CW;
1783
1784 if (alt) {
1785 lkb->lkb_rqmode = alt;
1786 rv = _can_be_granted(r, lkb, now);
1787 if (rv)
1788 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
1789 else
1790 lkb->lkb_rqmode = rqmode;
1791 }
1792 out:
1793 return rv;
1794}
1795
1796/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
1797 for locks pending on the convert list. Once verified (watch for these
1798 log_prints), we should be able to just call _can_be_granted() and not
1799 bother with the demote/deadlk cases here (and there's no easy way to deal
1800 with a deadlk here, we'd have to generate something like grant_lock with
1801 the deadlk error.) */
1802
1803/* Returns the highest requested mode of all blocked conversions; sets
1804 cw if there's a blocked conversion to DLM_LOCK_CW. */
1805
1806static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw)
1807{
1808 struct dlm_lkb *lkb, *s;
1809 int hi, demoted, quit, grant_restart, demote_restart;
1810 int deadlk;
1811
1812 quit = 0;
1813 restart:
1814 grant_restart = 0;
1815 demote_restart = 0;
1816 hi = DLM_LOCK_IV;
1817
1818 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
1819 demoted = is_demoted(lkb);
1820 deadlk = 0;
1821
1822 if (can_be_granted(r, lkb, 0, &deadlk)) {
1823 grant_lock_pending(r, lkb);
1824 grant_restart = 1;
1825 continue;
1826 }
1827
1828 if (!demoted && is_demoted(lkb)) {
1829 log_print("WARN: pending demoted %x node %d %s",
1830 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1831 demote_restart = 1;
1832 continue;
1833 }
1834
1835 if (deadlk) {
1836 log_print("WARN: pending deadlock %x node %d %s",
1837 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1838 dlm_dump_rsb(r);
1839 continue;
1840 }
1841
1842 hi = max_t(int, lkb->lkb_rqmode, hi);
1843
1844 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
1845 *cw = 1;
1846 }
1847
1848 if (grant_restart)
1849 goto restart;
1850 if (demote_restart && !quit) {
1851 quit = 1;
1852 goto restart;
1853 }
1854
1855 return max_t(int, high, hi);
1856}
1857
1858static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw)
1859{
1860 struct dlm_lkb *lkb, *s;
1861
1862 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
1863 if (can_be_granted(r, lkb, 0, NULL))
1864 grant_lock_pending(r, lkb);
1865 else {
1866 high = max_t(int, lkb->lkb_rqmode, high);
1867 if (lkb->lkb_rqmode == DLM_LOCK_CW)
1868 *cw = 1;
1869 }
1870 }
1871
1872 return high;
1873}
1874
1875/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
1876 on either the convert or waiting queue.
1877 high is the largest rqmode of all locks blocked on the convert or
1878 waiting queue. */
1879
1880static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
1881{
1882 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
1883 if (gr->lkb_highbast < DLM_LOCK_EX)
1884 return 1;
1885 return 0;
1886 }
1887
1888 if (gr->lkb_highbast < high &&
1889 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
1890 return 1;
1891 return 0;
1892}
1893
1894static void grant_pending_locks(struct dlm_rsb *r)
1895{
1896 struct dlm_lkb *lkb, *s;
1897 int high = DLM_LOCK_IV;
1898 int cw = 0;
1899
1900 DLM_ASSERT(is_master(r), dlm_dump_rsb(r););
1901
1902 high = grant_pending_convert(r, high, &cw);
1903 high = grant_pending_wait(r, high, &cw);
1904
1905 if (high == DLM_LOCK_IV)
1906 return;
1907
1908 /*
1909 * If there are locks left on the wait/convert queue then send blocking
1910 * ASTs to granted locks based on the largest requested mode (high)
1911 * found above.
1912 */
1913
1914 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
1915 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
1916 if (cw && high == DLM_LOCK_PR &&
1917 lkb->lkb_grmode == DLM_LOCK_PR)
1918 queue_bast(r, lkb, DLM_LOCK_CW);
1919 else
1920 queue_bast(r, lkb, high);
1921 lkb->lkb_highbast = high;
1922 }
1923 }
1924}
1925
1926static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
1927{
1928 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
1929 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
1930 if (gr->lkb_highbast < DLM_LOCK_EX)
1931 return 1;
1932 return 0;
1933 }
1934
1935 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
1936 return 1;
1937 return 0;
1938}
1939
1940static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
1941 struct dlm_lkb *lkb)
1942{
1943 struct dlm_lkb *gr;
1944
1945 list_for_each_entry(gr, head, lkb_statequeue) {
1946 /* skip self when sending basts to convertqueue */
1947 if (gr == lkb)
1948 continue;
1949 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
1950 queue_bast(r, gr, lkb->lkb_rqmode);
1951 gr->lkb_highbast = lkb->lkb_rqmode;
1952 }
1953 }
1954}
1955
1956static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
1957{
1958 send_bast_queue(r, &r->res_grantqueue, lkb);
1959}
1960
1961static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
1962{
1963 send_bast_queue(r, &r->res_grantqueue, lkb);
1964 send_bast_queue(r, &r->res_convertqueue, lkb);
1965}
1966
1967/* set_master(r, lkb) -- set the master nodeid of a resource
1968
1969 The purpose of this function is to set the nodeid field in the given
1970 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
1971 known, it can just be copied to the lkb and the function will return
1972 0. If the rsb's nodeid is _not_ known, it needs to be looked up
1973 before it can be copied to the lkb.
1974
1975 When the rsb nodeid is being looked up remotely, the initial lkb
1976 causing the lookup is kept on the ls_waiters list waiting for the
1977 lookup reply. Other lkb's waiting for the same rsb lookup are kept
1978 on the rsb's res_lookup list until the master is verified.
1979
1980 Return values:
1981 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
1982 1: the rsb master is not available and the lkb has been placed on
1983 a wait queue
1984*/
1985
1986static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
1987{
1988 struct dlm_ls *ls = r->res_ls;
1989 int i, error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
1990
1991 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
1992 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
1993 r->res_first_lkid = lkb->lkb_id;
1994 lkb->lkb_nodeid = r->res_nodeid;
1995 return 0;
1996 }
1997
1998 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
1999 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2000 return 1;
2001 }
2002
2003 if (r->res_nodeid == 0) {
2004 lkb->lkb_nodeid = 0;
2005 return 0;
2006 }
2007
2008 if (r->res_nodeid > 0) {
2009 lkb->lkb_nodeid = r->res_nodeid;
2010 return 0;
2011 }
2012
2013 DLM_ASSERT(r->res_nodeid == -1, dlm_dump_rsb(r););
2014
2015 dir_nodeid = dlm_dir_nodeid(r);
2016
2017 if (dir_nodeid != our_nodeid) {
2018 r->res_first_lkid = lkb->lkb_id;
2019 send_lookup(r, lkb);
2020 return 1;
2021 }
2022
2023 for (i = 0; i < 2; i++) {
2024 /* It's possible for dlm_scand to remove an old rsb for
2025 this same resource from the toss list, us to create
2026 a new one, look up the master locally, and find it
2027 already exists just before dlm_scand does the
2028 dir_remove() on the previous rsb. */
2029
2030 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
2031 r->res_length, &ret_nodeid);
2032 if (!error)
2033 break;
2034 log_debug(ls, "dir_lookup error %d %s", error, r->res_name);
2035 schedule();
2036 }
2037 if (error && error != -EEXIST)
2038 return error;
2039
2040 if (ret_nodeid == our_nodeid) {
2041 r->res_first_lkid = 0;
2042 r->res_nodeid = 0;
2043 lkb->lkb_nodeid = 0;
2044 } else {
2045 r->res_first_lkid = lkb->lkb_id;
2046 r->res_nodeid = ret_nodeid;
2047 lkb->lkb_nodeid = ret_nodeid;
2048 }
2049 return 0;
2050}
2051
2052static void process_lookup_list(struct dlm_rsb *r)
2053{
2054 struct dlm_lkb *lkb, *safe;
2055
2056 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
2057 list_del_init(&lkb->lkb_rsb_lookup);
2058 _request_lock(r, lkb);
2059 schedule();
2060 }
2061}
2062
2063/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2064
2065static void confirm_master(struct dlm_rsb *r, int error)
2066{
2067 struct dlm_lkb *lkb;
2068
2069 if (!r->res_first_lkid)
2070 return;
2071
2072 switch (error) {
2073 case 0:
2074 case -EINPROGRESS:
2075 r->res_first_lkid = 0;
2076 process_lookup_list(r);
2077 break;
2078
2079 case -EAGAIN:
2080 case -EBADR:
2081 case -ENOTBLK:
2082 /* the remote request failed and won't be retried (it was
2083 a NOQUEUE, or has been canceled/unlocked); make a waiting
2084 lkb the first_lkid */
2085
2086 r->res_first_lkid = 0;
2087
2088 if (!list_empty(&r->res_lookup)) {
2089 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2090 lkb_rsb_lookup);
2091 list_del_init(&lkb->lkb_rsb_lookup);
2092 r->res_first_lkid = lkb->lkb_id;
2093 _request_lock(r, lkb);
2094 }
2095 break;
2096
2097 default:
2098 log_error(r->res_ls, "confirm_master unknown error %d", error);
2099 }
2100}
2101
2102static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
2103 int namelen, unsigned long timeout_cs,
2104 void (*ast) (void *astparam),
2105 void *astparam,
2106 void (*bast) (void *astparam, int mode),
2107 struct dlm_args *args)
2108{
2109 int rv = -EINVAL;
2110
2111 /* check for invalid arg usage */
2112
2113 if (mode < 0 || mode > DLM_LOCK_EX)
2114 goto out;
2115
2116 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2117 goto out;
2118
2119 if (flags & DLM_LKF_CANCEL)
2120 goto out;
2121
2122 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2123 goto out;
2124
2125 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2126 goto out;
2127
2128 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2129 goto out;
2130
2131 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2132 goto out;
2133
2134 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2135 goto out;
2136
2137 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2138 goto out;
2139
2140 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2141 goto out;
2142
2143 if (!ast || !lksb)
2144 goto out;
2145
2146 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2147 goto out;
2148
2149 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2150 goto out;
2151
2152 /* these args will be copied to the lkb in validate_lock_args,
2153 it cannot be done now because when converting locks, fields in
2154 an active lkb cannot be modified before locking the rsb */
2155
2156 args->flags = flags;
2157 args->astfn = ast;
2158 args->astparam = astparam;
2159 args->bastfn = bast;
2160 args->timeout = timeout_cs;
2161 args->mode = mode;
2162 args->lksb = lksb;
2163 rv = 0;
2164 out:
2165 return rv;
2166}
2167
2168static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2169{
2170 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2171 DLM_LKF_FORCEUNLOCK))
2172 return -EINVAL;
2173
2174 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2175 return -EINVAL;
2176
2177 args->flags = flags;
2178 args->astparam = astarg;
2179 return 0;
2180}
2181
2182static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2183 struct dlm_args *args)
2184{
2185 int rv = -EINVAL;
2186
2187 if (args->flags & DLM_LKF_CONVERT) {
2188 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2189 goto out;
2190
2191 if (args->flags & DLM_LKF_QUECVT &&
2192 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2193 goto out;
2194
2195 rv = -EBUSY;
2196 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2197 goto out;
2198
2199 if (lkb->lkb_wait_type)
2200 goto out;
2201
2202 if (is_overlap(lkb))
2203 goto out;
2204 }
2205
2206 lkb->lkb_exflags = args->flags;
2207 lkb->lkb_sbflags = 0;
2208 lkb->lkb_astfn = args->astfn;
2209 lkb->lkb_astparam = args->astparam;
2210 lkb->lkb_bastfn = args->bastfn;
2211 lkb->lkb_rqmode = args->mode;
2212 lkb->lkb_lksb = args->lksb;
2213 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2214 lkb->lkb_ownpid = (int) current->pid;
2215 lkb->lkb_timeout_cs = args->timeout;
2216 rv = 0;
2217 out:
2218 if (rv)
2219 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2220 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2221 lkb->lkb_status, lkb->lkb_wait_type,
2222 lkb->lkb_resource->res_name);
2223 return rv;
2224}
2225
2226/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2227 for success */
2228
2229/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2230 because there may be a lookup in progress and it's valid to do
2231 cancel/unlockf on it */
2232
2233static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2234{
2235 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
2236 int rv = -EINVAL;
2237
2238 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2239 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2240 dlm_print_lkb(lkb);
2241 goto out;
2242 }
2243
2244 /* an lkb may still exist even though the lock is EOL'ed due to a
2245 cancel, unlock or failed noqueue request; an app can't use these
2246 locks; return same error as if the lkid had not been found at all */
2247
2248 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2249 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2250 rv = -ENOENT;
2251 goto out;
2252 }
2253
2254 /* an lkb may be waiting for an rsb lookup to complete where the
2255 lookup was initiated by another lock */
2256
2257 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2258 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
2259 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2260 list_del_init(&lkb->lkb_rsb_lookup);
2261 queue_cast(lkb->lkb_resource, lkb,
2262 args->flags & DLM_LKF_CANCEL ?
2263 -DLM_ECANCEL : -DLM_EUNLOCK);
2264 unhold_lkb(lkb); /* undoes create_lkb() */
2265 }
2266 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2267 rv = -EBUSY;
2268 goto out;
2269 }
2270
2271 /* cancel not allowed with another cancel/unlock in progress */
2272
2273 if (args->flags & DLM_LKF_CANCEL) {
2274 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2275 goto out;
2276
2277 if (is_overlap(lkb))
2278 goto out;
2279
2280 /* don't let scand try to do a cancel */
2281 del_timeout(lkb);
2282
2283 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2284 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2285 rv = -EBUSY;
2286 goto out;
2287 }
2288
2289 /* there's nothing to cancel */
2290 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2291 !lkb->lkb_wait_type) {
2292 rv = -EBUSY;
2293 goto out;
2294 }
2295
2296 switch (lkb->lkb_wait_type) {
2297 case DLM_MSG_LOOKUP:
2298 case DLM_MSG_REQUEST:
2299 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2300 rv = -EBUSY;
2301 goto out;
2302 case DLM_MSG_UNLOCK:
2303 case DLM_MSG_CANCEL:
2304 goto out;
2305 }
2306 /* add_to_waiters() will set OVERLAP_CANCEL */
2307 goto out_ok;
2308 }
2309
2310 /* do we need to allow a force-unlock if there's a normal unlock
2311 already in progress? in what conditions could the normal unlock
2312 fail such that we'd want to send a force-unlock to be sure? */
2313
2314 if (args->flags & DLM_LKF_FORCEUNLOCK) {
2315 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
2316 goto out;
2317
2318 if (is_overlap_unlock(lkb))
2319 goto out;
2320
2321 /* don't let scand try to do a cancel */
2322 del_timeout(lkb);
2323
2324 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2325 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2326 rv = -EBUSY;
2327 goto out;
2328 }
2329
2330 switch (lkb->lkb_wait_type) {
2331 case DLM_MSG_LOOKUP:
2332 case DLM_MSG_REQUEST:
2333 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2334 rv = -EBUSY;
2335 goto out;
2336 case DLM_MSG_UNLOCK:
2337 goto out;
2338 }
2339 /* add_to_waiters() will set OVERLAP_UNLOCK */
2340 goto out_ok;
2341 }
2342
2343 /* normal unlock not allowed if there's any op in progress */
2344 rv = -EBUSY;
2345 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
2346 goto out;
2347
2348 out_ok:
2349 /* an overlapping op shouldn't blow away exflags from other op */
2350 lkb->lkb_exflags |= args->flags;
2351 lkb->lkb_sbflags = 0;
2352 lkb->lkb_astparam = args->astparam;
2353 rv = 0;
2354 out:
2355 if (rv)
2356 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
2357 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
2358 args->flags, lkb->lkb_wait_type,
2359 lkb->lkb_resource->res_name);
2360 return rv;
2361}
2362
2363/*
2364 * Four stage 4 varieties:
2365 * do_request(), do_convert(), do_unlock(), do_cancel()
2366 * These are called on the master node for the given lock and
2367 * from the central locking logic.
2368 */
2369
2370static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2371{
2372 int error = 0;
2373
2374 if (can_be_granted(r, lkb, 1, NULL)) {
2375 grant_lock(r, lkb);
2376 queue_cast(r, lkb, 0);
2377 goto out;
2378 }
2379
2380 if (can_be_queued(lkb)) {
2381 error = -EINPROGRESS;
2382 add_lkb(r, lkb, DLM_LKSTS_WAITING);
2383 add_timeout(lkb);
2384 goto out;
2385 }
2386
2387 error = -EAGAIN;
2388 queue_cast(r, lkb, -EAGAIN);
2389 out:
2390 return error;
2391}
2392
2393static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2394 int error)
2395{
2396 switch (error) {
2397 case -EAGAIN:
2398 if (force_blocking_asts(lkb))
2399 send_blocking_asts_all(r, lkb);
2400 break;
2401 case -EINPROGRESS:
2402 send_blocking_asts(r, lkb);
2403 break;
2404 }
2405}
2406
2407static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2408{
2409 int error = 0;
2410 int deadlk = 0;
2411
2412 /* changing an existing lock may allow others to be granted */
2413
2414 if (can_be_granted(r, lkb, 1, &deadlk)) {
2415 grant_lock(r, lkb);
2416 queue_cast(r, lkb, 0);
2417 goto out;
2418 }
2419
2420 /* can_be_granted() detected that this lock would block in a conversion
2421 deadlock, so we leave it on the granted queue and return EDEADLK in
2422 the ast for the convert. */
2423
2424 if (deadlk) {
2425 /* it's left on the granted queue */
2426 revert_lock(r, lkb);
2427 queue_cast(r, lkb, -EDEADLK);
2428 error = -EDEADLK;
2429 goto out;
2430 }
2431
2432 /* is_demoted() means the can_be_granted() above set the grmode
2433 to NL, and left us on the granted queue. This auto-demotion
2434 (due to CONVDEADLK) might mean other locks, and/or this lock, are
2435 now grantable. We have to try to grant other converting locks
2436 before we try again to grant this one. */
2437
2438 if (is_demoted(lkb)) {
2439 grant_pending_convert(r, DLM_LOCK_IV, NULL);
2440 if (_can_be_granted(r, lkb, 1)) {
2441 grant_lock(r, lkb);
2442 queue_cast(r, lkb, 0);
2443 goto out;
2444 }
2445 /* else fall through and move to convert queue */
2446 }
2447
2448 if (can_be_queued(lkb)) {
2449 error = -EINPROGRESS;
2450 del_lkb(r, lkb);
2451 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
2452 add_timeout(lkb);
2453 goto out;
2454 }
2455
2456 error = -EAGAIN;
2457 queue_cast(r, lkb, -EAGAIN);
2458 out:
2459 return error;
2460}
2461
2462static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2463 int error)
2464{
2465 switch (error) {
2466 case 0:
2467 grant_pending_locks(r);
2468 /* grant_pending_locks also sends basts */
2469 break;
2470 case -EAGAIN:
2471 if (force_blocking_asts(lkb))
2472 send_blocking_asts_all(r, lkb);
2473 break;
2474 case -EINPROGRESS:
2475 send_blocking_asts(r, lkb);
2476 break;
2477 }
2478}
2479
2480static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2481{
2482 remove_lock(r, lkb);
2483 queue_cast(r, lkb, -DLM_EUNLOCK);
2484 return -DLM_EUNLOCK;
2485}
2486
2487static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2488 int error)
2489{
2490 grant_pending_locks(r);
2491}
2492
2493/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
2494
2495static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2496{
2497 int error;
2498
2499 error = revert_lock(r, lkb);
2500 if (error) {
2501 queue_cast(r, lkb, -DLM_ECANCEL);
2502 return -DLM_ECANCEL;
2503 }
2504 return 0;
2505}
2506
2507static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2508 int error)
2509{
2510 if (error)
2511 grant_pending_locks(r);
2512}
2513
2514/*
2515 * Four stage 3 varieties:
2516 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
2517 */
2518
2519/* add a new lkb to a possibly new rsb, called by requesting process */
2520
2521static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2522{
2523 int error;
2524
2525 /* set_master: sets lkb nodeid from r */
2526
2527 error = set_master(r, lkb);
2528 if (error < 0)
2529 goto out;
2530 if (error) {
2531 error = 0;
2532 goto out;
2533 }
2534
2535 if (is_remote(r)) {
2536 /* receive_request() calls do_request() on remote node */
2537 error = send_request(r, lkb);
2538 } else {
2539 error = do_request(r, lkb);
2540 /* for remote locks the request_reply is sent
2541 between do_request and do_request_effects */
2542 do_request_effects(r, lkb, error);
2543 }
2544 out:
2545 return error;
2546}
2547
2548/* change some property of an existing lkb, e.g. mode */
2549
2550static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2551{
2552 int error;
2553
2554 if (is_remote(r)) {
2555 /* receive_convert() calls do_convert() on remote node */
2556 error = send_convert(r, lkb);
2557 } else {
2558 error = do_convert(r, lkb);
2559 /* for remote locks the convert_reply is sent
2560 between do_convert and do_convert_effects */
2561 do_convert_effects(r, lkb, error);
2562 }
2563
2564 return error;
2565}
2566
2567/* remove an existing lkb from the granted queue */
2568
2569static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2570{
2571 int error;
2572
2573 if (is_remote(r)) {
2574 /* receive_unlock() calls do_unlock() on remote node */
2575 error = send_unlock(r, lkb);
2576 } else {
2577 error = do_unlock(r, lkb);
2578 /* for remote locks the unlock_reply is sent
2579 between do_unlock and do_unlock_effects */
2580 do_unlock_effects(r, lkb, error);
2581 }
2582
2583 return error;
2584}
2585
2586/* remove an existing lkb from the convert or wait queue */
2587
2588static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2589{
2590 int error;
2591
2592 if (is_remote(r)) {
2593 /* receive_cancel() calls do_cancel() on remote node */
2594 error = send_cancel(r, lkb);
2595 } else {
2596 error = do_cancel(r, lkb);
2597 /* for remote locks the cancel_reply is sent
2598 between do_cancel and do_cancel_effects */
2599 do_cancel_effects(r, lkb, error);
2600 }
2601
2602 return error;
2603}
2604
2605/*
2606 * Four stage 2 varieties:
2607 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
2608 */
2609
2610static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
2611 int len, struct dlm_args *args)
2612{
2613 struct dlm_rsb *r;
2614 int error;
2615
2616 error = validate_lock_args(ls, lkb, args);
2617 if (error)
2618 goto out;
2619
2620 error = find_rsb(ls, name, len, R_CREATE, &r);
2621 if (error)
2622 goto out;
2623
2624 lock_rsb(r);
2625
2626 attach_lkb(r, lkb);
2627 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
2628
2629 error = _request_lock(r, lkb);
2630
2631 unlock_rsb(r);
2632 put_rsb(r);
2633
2634 out:
2635 return error;
2636}
2637
2638static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2639 struct dlm_args *args)
2640{
2641 struct dlm_rsb *r;
2642 int error;
2643
2644 r = lkb->lkb_resource;
2645
2646 hold_rsb(r);
2647 lock_rsb(r);
2648
2649 error = validate_lock_args(ls, lkb, args);
2650 if (error)
2651 goto out;
2652
2653 error = _convert_lock(r, lkb);
2654 out:
2655 unlock_rsb(r);
2656 put_rsb(r);
2657 return error;
2658}
2659
2660static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2661 struct dlm_args *args)
2662{
2663 struct dlm_rsb *r;
2664 int error;
2665
2666 r = lkb->lkb_resource;
2667
2668 hold_rsb(r);
2669 lock_rsb(r);
2670
2671 error = validate_unlock_args(lkb, args);
2672 if (error)
2673 goto out;
2674
2675 error = _unlock_lock(r, lkb);
2676 out:
2677 unlock_rsb(r);
2678 put_rsb(r);
2679 return error;
2680}
2681
2682static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2683 struct dlm_args *args)
2684{
2685 struct dlm_rsb *r;
2686 int error;
2687
2688 r = lkb->lkb_resource;
2689
2690 hold_rsb(r);
2691 lock_rsb(r);
2692
2693 error = validate_unlock_args(lkb, args);
2694 if (error)
2695 goto out;
2696
2697 error = _cancel_lock(r, lkb);
2698 out:
2699 unlock_rsb(r);
2700 put_rsb(r);
2701 return error;
2702}
2703
2704/*
2705 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
2706 */
2707
2708int dlm_lock(dlm_lockspace_t *lockspace,
2709 int mode,
2710 struct dlm_lksb *lksb,
2711 uint32_t flags,
2712 void *name,
2713 unsigned int namelen,
2714 uint32_t parent_lkid,
2715 void (*ast) (void *astarg),
2716 void *astarg,
2717 void (*bast) (void *astarg, int mode))
2718{
2719 struct dlm_ls *ls;
2720 struct dlm_lkb *lkb;
2721 struct dlm_args args;
2722 int error, convert = flags & DLM_LKF_CONVERT;
2723
2724 ls = dlm_find_lockspace_local(lockspace);
2725 if (!ls)
2726 return -EINVAL;
2727
2728 dlm_lock_recovery(ls);
2729
2730 if (convert)
2731 error = find_lkb(ls, lksb->sb_lkid, &lkb);
2732 else
2733 error = create_lkb(ls, &lkb);
2734
2735 if (error)
2736 goto out;
2737
2738 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
2739 astarg, bast, &args);
2740 if (error)
2741 goto out_put;
2742
2743 if (convert)
2744 error = convert_lock(ls, lkb, &args);
2745 else
2746 error = request_lock(ls, lkb, name, namelen, &args);
2747
2748 if (error == -EINPROGRESS)
2749 error = 0;
2750 out_put:
2751 if (convert || error)
2752 __put_lkb(ls, lkb);
2753 if (error == -EAGAIN || error == -EDEADLK)
2754 error = 0;
2755 out:
2756 dlm_unlock_recovery(ls);
2757 dlm_put_lockspace(ls);
2758 return error;
2759}
2760
2761int dlm_unlock(dlm_lockspace_t *lockspace,
2762 uint32_t lkid,
2763 uint32_t flags,
2764 struct dlm_lksb *lksb,
2765 void *astarg)
2766{
2767 struct dlm_ls *ls;
2768 struct dlm_lkb *lkb;
2769 struct dlm_args args;
2770 int error;
2771
2772 ls = dlm_find_lockspace_local(lockspace);
2773 if (!ls)
2774 return -EINVAL;
2775
2776 dlm_lock_recovery(ls);
2777
2778 error = find_lkb(ls, lkid, &lkb);
2779 if (error)
2780 goto out;
2781
2782 error = set_unlock_args(flags, astarg, &args);
2783 if (error)
2784 goto out_put;
2785
2786 if (flags & DLM_LKF_CANCEL)
2787 error = cancel_lock(ls, lkb, &args);
2788 else
2789 error = unlock_lock(ls, lkb, &args);
2790
2791 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
2792 error = 0;
2793 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
2794 error = 0;
2795 out_put:
2796 dlm_put_lkb(lkb);
2797 out:
2798 dlm_unlock_recovery(ls);
2799 dlm_put_lockspace(ls);
2800 return error;
2801}
2802
2803/*
2804 * send/receive routines for remote operations and replies
2805 *
2806 * send_args
2807 * send_common
2808 * send_request receive_request
2809 * send_convert receive_convert
2810 * send_unlock receive_unlock
2811 * send_cancel receive_cancel
2812 * send_grant receive_grant
2813 * send_bast receive_bast
2814 * send_lookup receive_lookup
2815 * send_remove receive_remove
2816 *
2817 * send_common_reply
2818 * receive_request_reply send_request_reply
2819 * receive_convert_reply send_convert_reply
2820 * receive_unlock_reply send_unlock_reply
2821 * receive_cancel_reply send_cancel_reply
2822 * receive_lookup_reply send_lookup_reply
2823 */
2824
2825static int _create_message(struct dlm_ls *ls, int mb_len,
2826 int to_nodeid, int mstype,
2827 struct dlm_message **ms_ret,
2828 struct dlm_mhandle **mh_ret)
2829{
2830 struct dlm_message *ms;
2831 struct dlm_mhandle *mh;
2832 char *mb;
2833
2834 /* get_buffer gives us a message handle (mh) that we need to
2835 pass into lowcomms_commit and a message buffer (mb) that we
2836 write our data into */
2837
2838 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
2839 if (!mh)
2840 return -ENOBUFS;
2841
2842 memset(mb, 0, mb_len);
2843
2844 ms = (struct dlm_message *) mb;
2845
2846 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
2847 ms->m_header.h_lockspace = ls->ls_global_id;
2848 ms->m_header.h_nodeid = dlm_our_nodeid();
2849 ms->m_header.h_length = mb_len;
2850 ms->m_header.h_cmd = DLM_MSG;
2851
2852 ms->m_type = mstype;
2853
2854 *mh_ret = mh;
2855 *ms_ret = ms;
2856 return 0;
2857}
2858
2859static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
2860 int to_nodeid, int mstype,
2861 struct dlm_message **ms_ret,
2862 struct dlm_mhandle **mh_ret)
2863{
2864 int mb_len = sizeof(struct dlm_message);
2865
2866 switch (mstype) {
2867 case DLM_MSG_REQUEST:
2868 case DLM_MSG_LOOKUP:
2869 case DLM_MSG_REMOVE:
2870 mb_len += r->res_length;
2871 break;
2872 case DLM_MSG_CONVERT:
2873 case DLM_MSG_UNLOCK:
2874 case DLM_MSG_REQUEST_REPLY:
2875 case DLM_MSG_CONVERT_REPLY:
2876 case DLM_MSG_GRANT:
2877 if (lkb && lkb->lkb_lvbptr)
2878 mb_len += r->res_ls->ls_lvblen;
2879 break;
2880 }
2881
2882 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
2883 ms_ret, mh_ret);
2884}
2885
2886/* further lowcomms enhancements or alternate implementations may make
2887 the return value from this function useful at some point */
2888
2889static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
2890{
2891 dlm_message_out(ms);
2892 dlm_lowcomms_commit_buffer(mh);
2893 return 0;
2894}
2895
2896static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
2897 struct dlm_message *ms)
2898{
2899 ms->m_nodeid = lkb->lkb_nodeid;
2900 ms->m_pid = lkb->lkb_ownpid;
2901 ms->m_lkid = lkb->lkb_id;
2902 ms->m_remid = lkb->lkb_remid;
2903 ms->m_exflags = lkb->lkb_exflags;
2904 ms->m_sbflags = lkb->lkb_sbflags;
2905 ms->m_flags = lkb->lkb_flags;
2906 ms->m_lvbseq = lkb->lkb_lvbseq;
2907 ms->m_status = lkb->lkb_status;
2908 ms->m_grmode = lkb->lkb_grmode;
2909 ms->m_rqmode = lkb->lkb_rqmode;
2910 ms->m_hash = r->res_hash;
2911
2912 /* m_result and m_bastmode are set from function args,
2913 not from lkb fields */
2914
2915 if (lkb->lkb_bastfn)
2916 ms->m_asts |= DLM_CB_BAST;
2917 if (lkb->lkb_astfn)
2918 ms->m_asts |= DLM_CB_CAST;
2919
2920 /* compare with switch in create_message; send_remove() doesn't
2921 use send_args() */
2922
2923 switch (ms->m_type) {
2924 case DLM_MSG_REQUEST:
2925 case DLM_MSG_LOOKUP:
2926 memcpy(ms->m_extra, r->res_name, r->res_length);
2927 break;
2928 case DLM_MSG_CONVERT:
2929 case DLM_MSG_UNLOCK:
2930 case DLM_MSG_REQUEST_REPLY:
2931 case DLM_MSG_CONVERT_REPLY:
2932 case DLM_MSG_GRANT:
2933 if (!lkb->lkb_lvbptr)
2934 break;
2935 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2936 break;
2937 }
2938}
2939
2940static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
2941{
2942 struct dlm_message *ms;
2943 struct dlm_mhandle *mh;
2944 int to_nodeid, error;
2945
2946 to_nodeid = r->res_nodeid;
2947
2948 error = add_to_waiters(lkb, mstype, to_nodeid);
2949 if (error)
2950 return error;
2951
2952 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
2953 if (error)
2954 goto fail;
2955
2956 send_args(r, lkb, ms);
2957
2958 error = send_message(mh, ms);
2959 if (error)
2960 goto fail;
2961 return 0;
2962
2963 fail:
2964 remove_from_waiters(lkb, msg_reply_type(mstype));
2965 return error;
2966}
2967
2968static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2969{
2970 return send_common(r, lkb, DLM_MSG_REQUEST);
2971}
2972
2973static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2974{
2975 int error;
2976
2977 error = send_common(r, lkb, DLM_MSG_CONVERT);
2978
2979 /* down conversions go without a reply from the master */
2980 if (!error && down_conversion(lkb)) {
2981 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2982 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
2983 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
2984 r->res_ls->ls_stub_ms.m_result = 0;
2985 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
2986 }
2987
2988 return error;
2989}
2990
2991/* FIXME: if this lkb is the only lock we hold on the rsb, then set
2992 MASTER_UNCERTAIN to force the next request on the rsb to confirm
2993 that the master is still correct. */
2994
2995static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2996{
2997 return send_common(r, lkb, DLM_MSG_UNLOCK);
2998}
2999
3000static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3001{
3002 return send_common(r, lkb, DLM_MSG_CANCEL);
3003}
3004
3005static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3006{
3007 struct dlm_message *ms;
3008 struct dlm_mhandle *mh;
3009 int to_nodeid, error;
3010
3011 to_nodeid = lkb->lkb_nodeid;
3012
3013 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3014 if (error)
3015 goto out;
3016
3017 send_args(r, lkb, ms);
3018
3019 ms->m_result = 0;
3020
3021 error = send_message(mh, ms);
3022 out:
3023 return error;
3024}
3025
3026static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3027{
3028 struct dlm_message *ms;
3029 struct dlm_mhandle *mh;
3030 int to_nodeid, error;
3031
3032 to_nodeid = lkb->lkb_nodeid;
3033
3034 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3035 if (error)
3036 goto out;
3037
3038 send_args(r, lkb, ms);
3039
3040 ms->m_bastmode = mode;
3041
3042 error = send_message(mh, ms);
3043 out:
3044 return error;
3045}
3046
3047static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3048{
3049 struct dlm_message *ms;
3050 struct dlm_mhandle *mh;
3051 int to_nodeid, error;
3052
3053 to_nodeid = dlm_dir_nodeid(r);
3054
3055 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
3056 if (error)
3057 return error;
3058
3059 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3060 if (error)
3061 goto fail;
3062
3063 send_args(r, lkb, ms);
3064
3065 error = send_message(mh, ms);
3066 if (error)
3067 goto fail;
3068 return 0;
3069
3070 fail:
3071 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3072 return error;
3073}
3074
3075static int send_remove(struct dlm_rsb *r)
3076{
3077 struct dlm_message *ms;
3078 struct dlm_mhandle *mh;
3079 int to_nodeid, error;
3080
3081 to_nodeid = dlm_dir_nodeid(r);
3082
3083 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3084 if (error)
3085 goto out;
3086
3087 memcpy(ms->m_extra, r->res_name, r->res_length);
3088 ms->m_hash = r->res_hash;
3089
3090 error = send_message(mh, ms);
3091 out:
3092 return error;
3093}
3094
3095static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3096 int mstype, int rv)
3097{
3098 struct dlm_message *ms;
3099 struct dlm_mhandle *mh;
3100 int to_nodeid, error;
3101
3102 to_nodeid = lkb->lkb_nodeid;
3103
3104 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3105 if (error)
3106 goto out;
3107
3108 send_args(r, lkb, ms);
3109
3110 ms->m_result = rv;
3111
3112 error = send_message(mh, ms);
3113 out:
3114 return error;
3115}
3116
3117static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3118{
3119 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3120}
3121
3122static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3123{
3124 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3125}
3126
3127static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3128{
3129 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3130}
3131
3132static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3133{
3134 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3135}
3136
3137static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3138 int ret_nodeid, int rv)
3139{
3140 struct dlm_rsb *r = &ls->ls_stub_rsb;
3141 struct dlm_message *ms;
3142 struct dlm_mhandle *mh;
3143 int error, nodeid = ms_in->m_header.h_nodeid;
3144
3145 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3146 if (error)
3147 goto out;
3148
3149 ms->m_lkid = ms_in->m_lkid;
3150 ms->m_result = rv;
3151 ms->m_nodeid = ret_nodeid;
3152
3153 error = send_message(mh, ms);
3154 out:
3155 return error;
3156}
3157
3158/* which args we save from a received message depends heavily on the type
3159 of message, unlike the send side where we can safely send everything about
3160 the lkb for any type of message */
3161
3162static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3163{
3164 lkb->lkb_exflags = ms->m_exflags;
3165 lkb->lkb_sbflags = ms->m_sbflags;
3166 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3167 (ms->m_flags & 0x0000FFFF);
3168}
3169
3170static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3171{
3172 if (ms->m_flags == DLM_IFL_STUB_MS)
3173 return;
3174
3175 lkb->lkb_sbflags = ms->m_sbflags;
3176 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3177 (ms->m_flags & 0x0000FFFF);
3178}
3179
3180static int receive_extralen(struct dlm_message *ms)
3181{
3182 return (ms->m_header.h_length - sizeof(struct dlm_message));
3183}
3184
3185static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3186 struct dlm_message *ms)
3187{
3188 int len;
3189
3190 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3191 if (!lkb->lkb_lvbptr)
3192 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3193 if (!lkb->lkb_lvbptr)
3194 return -ENOMEM;
3195 len = receive_extralen(ms);
3196 if (len > DLM_RESNAME_MAXLEN)
3197 len = DLM_RESNAME_MAXLEN;
3198 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3199 }
3200 return 0;
3201}
3202
3203static void fake_bastfn(void *astparam, int mode)
3204{
3205 log_print("fake_bastfn should not be called");
3206}
3207
3208static void fake_astfn(void *astparam)
3209{
3210 log_print("fake_astfn should not be called");
3211}
3212
3213static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3214 struct dlm_message *ms)
3215{
3216 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3217 lkb->lkb_ownpid = ms->m_pid;
3218 lkb->lkb_remid = ms->m_lkid;
3219 lkb->lkb_grmode = DLM_LOCK_IV;
3220 lkb->lkb_rqmode = ms->m_rqmode;
3221
3222 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3223 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
3224
3225 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3226 /* lkb was just created so there won't be an lvb yet */
3227 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3228 if (!lkb->lkb_lvbptr)
3229 return -ENOMEM;
3230 }
3231
3232 return 0;
3233}
3234
3235static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3236 struct dlm_message *ms)
3237{
3238 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3239 return -EBUSY;
3240
3241 if (receive_lvb(ls, lkb, ms))
3242 return -ENOMEM;
3243
3244 lkb->lkb_rqmode = ms->m_rqmode;
3245 lkb->lkb_lvbseq = ms->m_lvbseq;
3246
3247 return 0;
3248}
3249
3250static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3251 struct dlm_message *ms)
3252{
3253 if (receive_lvb(ls, lkb, ms))
3254 return -ENOMEM;
3255 return 0;
3256}
3257
3258/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3259 uses to send a reply and that the remote end uses to process the reply. */
3260
3261static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3262{
3263 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3264 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3265 lkb->lkb_remid = ms->m_lkid;
3266}
3267
3268/* This is called after the rsb is locked so that we can safely inspect
3269 fields in the lkb. */
3270
3271static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3272{
3273 int from = ms->m_header.h_nodeid;
3274 int error = 0;
3275
3276 switch (ms->m_type) {
3277 case DLM_MSG_CONVERT:
3278 case DLM_MSG_UNLOCK:
3279 case DLM_MSG_CANCEL:
3280 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3281 error = -EINVAL;
3282 break;
3283
3284 case DLM_MSG_CONVERT_REPLY:
3285 case DLM_MSG_UNLOCK_REPLY:
3286 case DLM_MSG_CANCEL_REPLY:
3287 case DLM_MSG_GRANT:
3288 case DLM_MSG_BAST:
3289 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3290 error = -EINVAL;
3291 break;
3292
3293 case DLM_MSG_REQUEST_REPLY:
3294 if (!is_process_copy(lkb))
3295 error = -EINVAL;
3296 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3297 error = -EINVAL;
3298 break;
3299
3300 default:
3301 error = -EINVAL;
3302 }
3303
3304 if (error)
3305 log_error(lkb->lkb_resource->res_ls,
3306 "ignore invalid message %d from %d %x %x %x %d",
3307 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
3308 lkb->lkb_flags, lkb->lkb_nodeid);
3309 return error;
3310}
3311
3312static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
3313{
3314 struct dlm_lkb *lkb;
3315 struct dlm_rsb *r;
3316 int error, namelen;
3317
3318 error = create_lkb(ls, &lkb);
3319 if (error)
3320 goto fail;
3321
3322 receive_flags(lkb, ms);
3323 lkb->lkb_flags |= DLM_IFL_MSTCPY;
3324 error = receive_request_args(ls, lkb, ms);
3325 if (error) {
3326 __put_lkb(ls, lkb);
3327 goto fail;
3328 }
3329
3330 namelen = receive_extralen(ms);
3331
3332 error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r);
3333 if (error) {
3334 __put_lkb(ls, lkb);
3335 goto fail;
3336 }
3337
3338 lock_rsb(r);
3339
3340 attach_lkb(r, lkb);
3341 error = do_request(r, lkb);
3342 send_request_reply(r, lkb, error);
3343 do_request_effects(r, lkb, error);
3344
3345 unlock_rsb(r);
3346 put_rsb(r);
3347
3348 if (error == -EINPROGRESS)
3349 error = 0;
3350 if (error)
3351 dlm_put_lkb(lkb);
3352 return;
3353
3354 fail:
3355 setup_stub_lkb(ls, ms);
3356 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3357}
3358
3359static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
3360{
3361 struct dlm_lkb *lkb;
3362 struct dlm_rsb *r;
3363 int error, reply = 1;
3364
3365 error = find_lkb(ls, ms->m_remid, &lkb);
3366 if (error)
3367 goto fail;
3368
3369 r = lkb->lkb_resource;
3370
3371 hold_rsb(r);
3372 lock_rsb(r);
3373
3374 error = validate_message(lkb, ms);
3375 if (error)
3376 goto out;
3377
3378 receive_flags(lkb, ms);
3379
3380 error = receive_convert_args(ls, lkb, ms);
3381 if (error) {
3382 send_convert_reply(r, lkb, error);
3383 goto out;
3384 }
3385
3386 reply = !down_conversion(lkb);
3387
3388 error = do_convert(r, lkb);
3389 if (reply)
3390 send_convert_reply(r, lkb, error);
3391 do_convert_effects(r, lkb, error);
3392 out:
3393 unlock_rsb(r);
3394 put_rsb(r);
3395 dlm_put_lkb(lkb);
3396 return;
3397
3398 fail:
3399 setup_stub_lkb(ls, ms);
3400 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3401}
3402
3403static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
3404{
3405 struct dlm_lkb *lkb;
3406 struct dlm_rsb *r;
3407 int error;
3408
3409 error = find_lkb(ls, ms->m_remid, &lkb);
3410 if (error)
3411 goto fail;
3412
3413 r = lkb->lkb_resource;
3414
3415 hold_rsb(r);
3416 lock_rsb(r);
3417
3418 error = validate_message(lkb, ms);
3419 if (error)
3420 goto out;
3421
3422 receive_flags(lkb, ms);
3423
3424 error = receive_unlock_args(ls, lkb, ms);
3425 if (error) {
3426 send_unlock_reply(r, lkb, error);
3427 goto out;
3428 }
3429
3430 error = do_unlock(r, lkb);
3431 send_unlock_reply(r, lkb, error);
3432 do_unlock_effects(r, lkb, error);
3433 out:
3434 unlock_rsb(r);
3435 put_rsb(r);
3436 dlm_put_lkb(lkb);
3437 return;
3438
3439 fail:
3440 setup_stub_lkb(ls, ms);
3441 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3442}
3443
3444static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
3445{
3446 struct dlm_lkb *lkb;
3447 struct dlm_rsb *r;
3448 int error;
3449
3450 error = find_lkb(ls, ms->m_remid, &lkb);
3451 if (error)
3452 goto fail;
3453
3454 receive_flags(lkb, ms);
3455
3456 r = lkb->lkb_resource;
3457
3458 hold_rsb(r);
3459 lock_rsb(r);
3460
3461 error = validate_message(lkb, ms);
3462 if (error)
3463 goto out;
3464
3465 error = do_cancel(r, lkb);
3466 send_cancel_reply(r, lkb, error);
3467 do_cancel_effects(r, lkb, error);
3468 out:
3469 unlock_rsb(r);
3470 put_rsb(r);
3471 dlm_put_lkb(lkb);
3472 return;
3473
3474 fail:
3475 setup_stub_lkb(ls, ms);
3476 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3477}
3478
3479static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
3480{
3481 struct dlm_lkb *lkb;
3482 struct dlm_rsb *r;
3483 int error;
3484
3485 error = find_lkb(ls, ms->m_remid, &lkb);
3486 if (error) {
3487 log_debug(ls, "receive_grant from %d no lkb %x",
3488 ms->m_header.h_nodeid, ms->m_remid);
3489 return;
3490 }
3491
3492 r = lkb->lkb_resource;
3493
3494 hold_rsb(r);
3495 lock_rsb(r);
3496
3497 error = validate_message(lkb, ms);
3498 if (error)
3499 goto out;
3500
3501 receive_flags_reply(lkb, ms);
3502 if (is_altmode(lkb))
3503 munge_altmode(lkb, ms);
3504 grant_lock_pc(r, lkb, ms);
3505 queue_cast(r, lkb, 0);
3506 out:
3507 unlock_rsb(r);
3508 put_rsb(r);
3509 dlm_put_lkb(lkb);
3510}
3511
3512static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
3513{
3514 struct dlm_lkb *lkb;
3515 struct dlm_rsb *r;
3516 int error;
3517
3518 error = find_lkb(ls, ms->m_remid, &lkb);
3519 if (error) {
3520 log_debug(ls, "receive_bast from %d no lkb %x",
3521 ms->m_header.h_nodeid, ms->m_remid);
3522 return;
3523 }
3524
3525 r = lkb->lkb_resource;
3526
3527 hold_rsb(r);
3528 lock_rsb(r);
3529
3530 error = validate_message(lkb, ms);
3531 if (error)
3532 goto out;
3533
3534 queue_bast(r, lkb, ms->m_bastmode);
3535 out:
3536 unlock_rsb(r);
3537 put_rsb(r);
3538 dlm_put_lkb(lkb);
3539}
3540
3541static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
3542{
3543 int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid;
3544
3545 from_nodeid = ms->m_header.h_nodeid;
3546 our_nodeid = dlm_our_nodeid();
3547
3548 len = receive_extralen(ms);
3549
3550 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3551 if (dir_nodeid != our_nodeid) {
3552 log_error(ls, "lookup dir_nodeid %d from %d",
3553 dir_nodeid, from_nodeid);
3554 error = -EINVAL;
3555 ret_nodeid = -1;
3556 goto out;
3557 }
3558
3559 error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid);
3560
3561 /* Optimization: we're master so treat lookup as a request */
3562 if (!error && ret_nodeid == our_nodeid) {
3563 receive_request(ls, ms);
3564 return;
3565 }
3566 out:
3567 send_lookup_reply(ls, ms, ret_nodeid, error);
3568}
3569
3570static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
3571{
3572 int len, dir_nodeid, from_nodeid;
3573
3574 from_nodeid = ms->m_header.h_nodeid;
3575
3576 len = receive_extralen(ms);
3577
3578 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3579 if (dir_nodeid != dlm_our_nodeid()) {
3580 log_error(ls, "remove dir entry dir_nodeid %d from %d",
3581 dir_nodeid, from_nodeid);
3582 return;
3583 }
3584
3585 dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len);
3586}
3587
3588static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
3589{
3590 do_purge(ls, ms->m_nodeid, ms->m_pid);
3591}
3592
3593static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
3594{
3595 struct dlm_lkb *lkb;
3596 struct dlm_rsb *r;
3597 int error, mstype, result;
3598
3599 error = find_lkb(ls, ms->m_remid, &lkb);
3600 if (error) {
3601 log_debug(ls, "receive_request_reply from %d no lkb %x",
3602 ms->m_header.h_nodeid, ms->m_remid);
3603 return;
3604 }
3605
3606 r = lkb->lkb_resource;
3607 hold_rsb(r);
3608 lock_rsb(r);
3609
3610 error = validate_message(lkb, ms);
3611 if (error)
3612 goto out;
3613
3614 mstype = lkb->lkb_wait_type;
3615 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
3616 if (error)
3617 goto out;
3618
3619 /* Optimization: the dir node was also the master, so it took our
3620 lookup as a request and sent request reply instead of lookup reply */
3621 if (mstype == DLM_MSG_LOOKUP) {
3622 r->res_nodeid = ms->m_header.h_nodeid;
3623 lkb->lkb_nodeid = r->res_nodeid;
3624 }
3625
3626 /* this is the value returned from do_request() on the master */
3627 result = ms->m_result;
3628
3629 switch (result) {
3630 case -EAGAIN:
3631 /* request would block (be queued) on remote master */
3632 queue_cast(r, lkb, -EAGAIN);
3633 confirm_master(r, -EAGAIN);
3634 unhold_lkb(lkb); /* undoes create_lkb() */
3635 break;
3636
3637 case -EINPROGRESS:
3638 case 0:
3639 /* request was queued or granted on remote master */
3640 receive_flags_reply(lkb, ms);
3641 lkb->lkb_remid = ms->m_lkid;
3642 if (is_altmode(lkb))
3643 munge_altmode(lkb, ms);
3644 if (result) {
3645 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3646 add_timeout(lkb);
3647 } else {
3648 grant_lock_pc(r, lkb, ms);
3649 queue_cast(r, lkb, 0);
3650 }
3651 confirm_master(r, result);
3652 break;
3653
3654 case -EBADR:
3655 case -ENOTBLK:
3656 /* find_rsb failed to find rsb or rsb wasn't master */
3657 log_debug(ls, "receive_request_reply %x %x master diff %d %d",
3658 lkb->lkb_id, lkb->lkb_flags, r->res_nodeid, result);
3659 r->res_nodeid = -1;
3660 lkb->lkb_nodeid = -1;
3661
3662 if (is_overlap(lkb)) {
3663 /* we'll ignore error in cancel/unlock reply */
3664 queue_cast_overlap(r, lkb);
3665 confirm_master(r, result);
3666 unhold_lkb(lkb); /* undoes create_lkb() */
3667 } else
3668 _request_lock(r, lkb);
3669 break;
3670
3671 default:
3672 log_error(ls, "receive_request_reply %x error %d",
3673 lkb->lkb_id, result);
3674 }
3675
3676 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
3677 log_debug(ls, "receive_request_reply %x result %d unlock",
3678 lkb->lkb_id, result);
3679 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3680 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3681 send_unlock(r, lkb);
3682 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
3683 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
3684 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3685 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3686 send_cancel(r, lkb);
3687 } else {
3688 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3689 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3690 }
3691 out:
3692 unlock_rsb(r);
3693 put_rsb(r);
3694 dlm_put_lkb(lkb);
3695}
3696
3697static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3698 struct dlm_message *ms)
3699{
3700 /* this is the value returned from do_convert() on the master */
3701 switch (ms->m_result) {
3702 case -EAGAIN:
3703 /* convert would block (be queued) on remote master */
3704 queue_cast(r, lkb, -EAGAIN);
3705 break;
3706
3707 case -EDEADLK:
3708 receive_flags_reply(lkb, ms);
3709 revert_lock_pc(r, lkb);
3710 queue_cast(r, lkb, -EDEADLK);
3711 break;
3712
3713 case -EINPROGRESS:
3714 /* convert was queued on remote master */
3715 receive_flags_reply(lkb, ms);
3716 if (is_demoted(lkb))
3717 munge_demoted(lkb);
3718 del_lkb(r, lkb);
3719 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3720 add_timeout(lkb);
3721 break;
3722
3723 case 0:
3724 /* convert was granted on remote master */
3725 receive_flags_reply(lkb, ms);
3726 if (is_demoted(lkb))
3727 munge_demoted(lkb);
3728 grant_lock_pc(r, lkb, ms);
3729 queue_cast(r, lkb, 0);
3730 break;
3731
3732 default:
3733 log_error(r->res_ls, "receive_convert_reply %x error %d",
3734 lkb->lkb_id, ms->m_result);
3735 }
3736}
3737
3738static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3739{
3740 struct dlm_rsb *r = lkb->lkb_resource;
3741 int error;
3742
3743 hold_rsb(r);
3744 lock_rsb(r);
3745
3746 error = validate_message(lkb, ms);
3747 if (error)
3748 goto out;
3749
3750 /* stub reply can happen with waiters_mutex held */
3751 error = remove_from_waiters_ms(lkb, ms);
3752 if (error)
3753 goto out;
3754
3755 __receive_convert_reply(r, lkb, ms);
3756 out:
3757 unlock_rsb(r);
3758 put_rsb(r);
3759}
3760
3761static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
3762{
3763 struct dlm_lkb *lkb;
3764 int error;
3765
3766 error = find_lkb(ls, ms->m_remid, &lkb);
3767 if (error) {
3768 log_debug(ls, "receive_convert_reply from %d no lkb %x",
3769 ms->m_header.h_nodeid, ms->m_remid);
3770 return;
3771 }
3772
3773 _receive_convert_reply(lkb, ms);
3774 dlm_put_lkb(lkb);
3775}
3776
3777static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3778{
3779 struct dlm_rsb *r = lkb->lkb_resource;
3780 int error;
3781
3782 hold_rsb(r);
3783 lock_rsb(r);
3784
3785 error = validate_message(lkb, ms);
3786 if (error)
3787 goto out;
3788
3789 /* stub reply can happen with waiters_mutex held */
3790 error = remove_from_waiters_ms(lkb, ms);
3791 if (error)
3792 goto out;
3793
3794 /* this is the value returned from do_unlock() on the master */
3795
3796 switch (ms->m_result) {
3797 case -DLM_EUNLOCK:
3798 receive_flags_reply(lkb, ms);
3799 remove_lock_pc(r, lkb);
3800 queue_cast(r, lkb, -DLM_EUNLOCK);
3801 break;
3802 case -ENOENT:
3803 break;
3804 default:
3805 log_error(r->res_ls, "receive_unlock_reply %x error %d",
3806 lkb->lkb_id, ms->m_result);
3807 }
3808 out:
3809 unlock_rsb(r);
3810 put_rsb(r);
3811}
3812
3813static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
3814{
3815 struct dlm_lkb *lkb;
3816 int error;
3817
3818 error = find_lkb(ls, ms->m_remid, &lkb);
3819 if (error) {
3820 log_debug(ls, "receive_unlock_reply from %d no lkb %x",
3821 ms->m_header.h_nodeid, ms->m_remid);
3822 return;
3823 }
3824
3825 _receive_unlock_reply(lkb, ms);
3826 dlm_put_lkb(lkb);
3827}
3828
3829static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3830{
3831 struct dlm_rsb *r = lkb->lkb_resource;
3832 int error;
3833
3834 hold_rsb(r);
3835 lock_rsb(r);
3836
3837 error = validate_message(lkb, ms);
3838 if (error)
3839 goto out;
3840
3841 /* stub reply can happen with waiters_mutex held */
3842 error = remove_from_waiters_ms(lkb, ms);
3843 if (error)
3844 goto out;
3845
3846 /* this is the value returned from do_cancel() on the master */
3847
3848 switch (ms->m_result) {
3849 case -DLM_ECANCEL:
3850 receive_flags_reply(lkb, ms);
3851 revert_lock_pc(r, lkb);
3852 queue_cast(r, lkb, -DLM_ECANCEL);
3853 break;
3854 case 0:
3855 break;
3856 default:
3857 log_error(r->res_ls, "receive_cancel_reply %x error %d",
3858 lkb->lkb_id, ms->m_result);
3859 }
3860 out:
3861 unlock_rsb(r);
3862 put_rsb(r);
3863}
3864
3865static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
3866{
3867 struct dlm_lkb *lkb;
3868 int error;
3869
3870 error = find_lkb(ls, ms->m_remid, &lkb);
3871 if (error) {
3872 log_debug(ls, "receive_cancel_reply from %d no lkb %x",
3873 ms->m_header.h_nodeid, ms->m_remid);
3874 return;
3875 }
3876
3877 _receive_cancel_reply(lkb, ms);
3878 dlm_put_lkb(lkb);
3879}
3880
3881static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
3882{
3883 struct dlm_lkb *lkb;
3884 struct dlm_rsb *r;
3885 int error, ret_nodeid;
3886
3887 error = find_lkb(ls, ms->m_lkid, &lkb);
3888 if (error) {
3889 log_error(ls, "receive_lookup_reply no lkb");
3890 return;
3891 }
3892
3893 /* ms->m_result is the value returned by dlm_dir_lookup on dir node
3894 FIXME: will a non-zero error ever be returned? */
3895
3896 r = lkb->lkb_resource;
3897 hold_rsb(r);
3898 lock_rsb(r);
3899
3900 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3901 if (error)
3902 goto out;
3903
3904 ret_nodeid = ms->m_nodeid;
3905 if (ret_nodeid == dlm_our_nodeid()) {
3906 r->res_nodeid = 0;
3907 ret_nodeid = 0;
3908 r->res_first_lkid = 0;
3909 } else {
3910 /* set_master() will copy res_nodeid to lkb_nodeid */
3911 r->res_nodeid = ret_nodeid;
3912 }
3913
3914 if (is_overlap(lkb)) {
3915 log_debug(ls, "receive_lookup_reply %x unlock %x",
3916 lkb->lkb_id, lkb->lkb_flags);
3917 queue_cast_overlap(r, lkb);
3918 unhold_lkb(lkb); /* undoes create_lkb() */
3919 goto out_list;
3920 }
3921
3922 _request_lock(r, lkb);
3923
3924 out_list:
3925 if (!ret_nodeid)
3926 process_lookup_list(r);
3927 out:
3928 unlock_rsb(r);
3929 put_rsb(r);
3930 dlm_put_lkb(lkb);
3931}
3932
3933static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
3934{
3935 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
3936 log_debug(ls, "ignore non-member message %d from %d %x %x %d",
3937 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
3938 ms->m_remid, ms->m_result);
3939 return;
3940 }
3941
3942 switch (ms->m_type) {
3943
3944 /* messages sent to a master node */
3945
3946 case DLM_MSG_REQUEST:
3947 receive_request(ls, ms);
3948 break;
3949
3950 case DLM_MSG_CONVERT:
3951 receive_convert(ls, ms);
3952 break;
3953
3954 case DLM_MSG_UNLOCK:
3955 receive_unlock(ls, ms);
3956 break;
3957
3958 case DLM_MSG_CANCEL:
3959 receive_cancel(ls, ms);
3960 break;
3961
3962 /* messages sent from a master node (replies to above) */
3963
3964 case DLM_MSG_REQUEST_REPLY:
3965 receive_request_reply(ls, ms);
3966 break;
3967
3968 case DLM_MSG_CONVERT_REPLY:
3969 receive_convert_reply(ls, ms);
3970 break;
3971
3972 case DLM_MSG_UNLOCK_REPLY:
3973 receive_unlock_reply(ls, ms);
3974 break;
3975
3976 case DLM_MSG_CANCEL_REPLY:
3977 receive_cancel_reply(ls, ms);
3978 break;
3979
3980 /* messages sent from a master node (only two types of async msg) */
3981
3982 case DLM_MSG_GRANT:
3983 receive_grant(ls, ms);
3984 break;
3985
3986 case DLM_MSG_BAST:
3987 receive_bast(ls, ms);
3988 break;
3989
3990 /* messages sent to a dir node */
3991
3992 case DLM_MSG_LOOKUP:
3993 receive_lookup(ls, ms);
3994 break;
3995
3996 case DLM_MSG_REMOVE:
3997 receive_remove(ls, ms);
3998 break;
3999
4000 /* messages sent from a dir node (remove has no reply) */
4001
4002 case DLM_MSG_LOOKUP_REPLY:
4003 receive_lookup_reply(ls, ms);
4004 break;
4005
4006 /* other messages */
4007
4008 case DLM_MSG_PURGE:
4009 receive_purge(ls, ms);
4010 break;
4011
4012 default:
4013 log_error(ls, "unknown message type %d", ms->m_type);
4014 }
4015}
4016
4017/* If the lockspace is in recovery mode (locking stopped), then normal
4018 messages are saved on the requestqueue for processing after recovery is
4019 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4020 messages off the requestqueue before we process new ones. This occurs right
4021 after recovery completes when we transition from saving all messages on
4022 requestqueue, to processing all the saved messages, to processing new
4023 messages as they arrive. */
4024
4025static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4026 int nodeid)
4027{
4028 if (dlm_locking_stopped(ls)) {
4029 dlm_add_requestqueue(ls, nodeid, ms);
4030 } else {
4031 dlm_wait_requestqueue(ls);
4032 _receive_message(ls, ms);
4033 }
4034}
4035
4036/* This is called by dlm_recoverd to process messages that were saved on
4037 the requestqueue. */
4038
4039void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms)
4040{
4041 _receive_message(ls, ms);
4042}
4043
4044/* This is called by the midcomms layer when something is received for
4045 the lockspace. It could be either a MSG (normal message sent as part of
4046 standard locking activity) or an RCOM (recovery message sent as part of
4047 lockspace recovery). */
4048
4049void dlm_receive_buffer(union dlm_packet *p, int nodeid)
4050{
4051 struct dlm_header *hd = &p->header;
4052 struct dlm_ls *ls;
4053 int type = 0;
4054
4055 switch (hd->h_cmd) {
4056 case DLM_MSG:
4057 dlm_message_in(&p->message);
4058 type = p->message.m_type;
4059 break;
4060 case DLM_RCOM:
4061 dlm_rcom_in(&p->rcom);
4062 type = p->rcom.rc_type;
4063 break;
4064 default:
4065 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
4066 return;
4067 }
4068
4069 if (hd->h_nodeid != nodeid) {
4070 log_print("invalid h_nodeid %d from %d lockspace %x",
4071 hd->h_nodeid, nodeid, hd->h_lockspace);
4072 return;
4073 }
4074
4075 ls = dlm_find_lockspace_global(hd->h_lockspace);
4076 if (!ls) {
4077 if (dlm_config.ci_log_debug)
4078 log_print("invalid lockspace %x from %d cmd %d type %d",
4079 hd->h_lockspace, nodeid, hd->h_cmd, type);
4080
4081 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
4082 dlm_send_ls_not_ready(nodeid, &p->rcom);
4083 return;
4084 }
4085
4086 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
4087 be inactive (in this ls) before transitioning to recovery mode */
4088
4089 down_read(&ls->ls_recv_active);
4090 if (hd->h_cmd == DLM_MSG)
4091 dlm_receive_message(ls, &p->message, nodeid);
4092 else
4093 dlm_receive_rcom(ls, &p->rcom, nodeid);
4094 up_read(&ls->ls_recv_active);
4095
4096 dlm_put_lockspace(ls);
4097}
4098
4099static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
4100 struct dlm_message *ms_stub)
4101{
4102 if (middle_conversion(lkb)) {
4103 hold_lkb(lkb);
4104 memset(ms_stub, 0, sizeof(struct dlm_message));
4105 ms_stub->m_flags = DLM_IFL_STUB_MS;
4106 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
4107 ms_stub->m_result = -EINPROGRESS;
4108 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4109 _receive_convert_reply(lkb, ms_stub);
4110
4111 /* Same special case as in receive_rcom_lock_args() */
4112 lkb->lkb_grmode = DLM_LOCK_IV;
4113 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
4114 unhold_lkb(lkb);
4115
4116 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
4117 lkb->lkb_flags |= DLM_IFL_RESEND;
4118 }
4119
4120 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
4121 conversions are async; there's no reply from the remote master */
4122}
4123
4124/* A waiting lkb needs recovery if the master node has failed, or
4125 the master node is changing (only when no directory is used) */
4126
4127static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb)
4128{
4129 if (dlm_is_removed(ls, lkb->lkb_nodeid))
4130 return 1;
4131
4132 if (!dlm_no_directory(ls))
4133 return 0;
4134
4135 if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid)
4136 return 1;
4137
4138 return 0;
4139}
4140
4141/* Recovery for locks that are waiting for replies from nodes that are now
4142 gone. We can just complete unlocks and cancels by faking a reply from the
4143 dead node. Requests and up-conversions we flag to be resent after
4144 recovery. Down-conversions can just be completed with a fake reply like
4145 unlocks. Conversions between PR and CW need special attention. */
4146
4147void dlm_recover_waiters_pre(struct dlm_ls *ls)
4148{
4149 struct dlm_lkb *lkb, *safe;
4150 struct dlm_message *ms_stub;
4151 int wait_type, stub_unlock_result, stub_cancel_result;
4152
4153 ms_stub = kmalloc(sizeof(struct dlm_message), GFP_KERNEL);
4154 if (!ms_stub) {
4155 log_error(ls, "dlm_recover_waiters_pre no mem");
4156 return;
4157 }
4158
4159 mutex_lock(&ls->ls_waiters_mutex);
4160
4161 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
4162
4163 /* exclude debug messages about unlocks because there can be so
4164 many and they aren't very interesting */
4165
4166 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
4167 log_debug(ls, "recover_waiter %x nodeid %d "
4168 "msg %d to %d", lkb->lkb_id, lkb->lkb_nodeid,
4169 lkb->lkb_wait_type, lkb->lkb_wait_nodeid);
4170 }
4171
4172 /* all outstanding lookups, regardless of destination will be
4173 resent after recovery is done */
4174
4175 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
4176 lkb->lkb_flags |= DLM_IFL_RESEND;
4177 continue;
4178 }
4179
4180 if (!waiter_needs_recovery(ls, lkb))
4181 continue;
4182
4183 wait_type = lkb->lkb_wait_type;
4184 stub_unlock_result = -DLM_EUNLOCK;
4185 stub_cancel_result = -DLM_ECANCEL;
4186
4187 /* Main reply may have been received leaving a zero wait_type,
4188 but a reply for the overlapping op may not have been
4189 received. In that case we need to fake the appropriate
4190 reply for the overlap op. */
4191
4192 if (!wait_type) {
4193 if (is_overlap_cancel(lkb)) {
4194 wait_type = DLM_MSG_CANCEL;
4195 if (lkb->lkb_grmode == DLM_LOCK_IV)
4196 stub_cancel_result = 0;
4197 }
4198 if (is_overlap_unlock(lkb)) {
4199 wait_type = DLM_MSG_UNLOCK;
4200 if (lkb->lkb_grmode == DLM_LOCK_IV)
4201 stub_unlock_result = -ENOENT;
4202 }
4203
4204 log_debug(ls, "rwpre overlap %x %x %d %d %d",
4205 lkb->lkb_id, lkb->lkb_flags, wait_type,
4206 stub_cancel_result, stub_unlock_result);
4207 }
4208
4209 switch (wait_type) {
4210
4211 case DLM_MSG_REQUEST:
4212 lkb->lkb_flags |= DLM_IFL_RESEND;
4213 break;
4214
4215 case DLM_MSG_CONVERT:
4216 recover_convert_waiter(ls, lkb, ms_stub);
4217 break;
4218
4219 case DLM_MSG_UNLOCK:
4220 hold_lkb(lkb);
4221 memset(ms_stub, 0, sizeof(struct dlm_message));
4222 ms_stub->m_flags = DLM_IFL_STUB_MS;
4223 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
4224 ms_stub->m_result = stub_unlock_result;
4225 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4226 _receive_unlock_reply(lkb, ms_stub);
4227 dlm_put_lkb(lkb);
4228 break;
4229
4230 case DLM_MSG_CANCEL:
4231 hold_lkb(lkb);
4232 memset(ms_stub, 0, sizeof(struct dlm_message));
4233 ms_stub->m_flags = DLM_IFL_STUB_MS;
4234 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
4235 ms_stub->m_result = stub_cancel_result;
4236 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4237 _receive_cancel_reply(lkb, ms_stub);
4238 dlm_put_lkb(lkb);
4239 break;
4240
4241 default:
4242 log_error(ls, "invalid lkb wait_type %d %d",
4243 lkb->lkb_wait_type, wait_type);
4244 }
4245 schedule();
4246 }
4247 mutex_unlock(&ls->ls_waiters_mutex);
4248 kfree(ms_stub);
4249}
4250
4251static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
4252{
4253 struct dlm_lkb *lkb;
4254 int found = 0;
4255
4256 mutex_lock(&ls->ls_waiters_mutex);
4257 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
4258 if (lkb->lkb_flags & DLM_IFL_RESEND) {
4259 hold_lkb(lkb);
4260 found = 1;
4261 break;
4262 }
4263 }
4264 mutex_unlock(&ls->ls_waiters_mutex);
4265
4266 if (!found)
4267 lkb = NULL;
4268 return lkb;
4269}
4270
4271/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
4272 master or dir-node for r. Processing the lkb may result in it being placed
4273 back on waiters. */
4274
4275/* We do this after normal locking has been enabled and any saved messages
4276 (in requestqueue) have been processed. We should be confident that at
4277 this point we won't get or process a reply to any of these waiting
4278 operations. But, new ops may be coming in on the rsbs/locks here from
4279 userspace or remotely. */
4280
4281/* there may have been an overlap unlock/cancel prior to recovery or after
4282 recovery. if before, the lkb may still have a pos wait_count; if after, the
4283 overlap flag would just have been set and nothing new sent. we can be
4284 confident here than any replies to either the initial op or overlap ops
4285 prior to recovery have been received. */
4286
4287int dlm_recover_waiters_post(struct dlm_ls *ls)
4288{
4289 struct dlm_lkb *lkb;
4290 struct dlm_rsb *r;
4291 int error = 0, mstype, err, oc, ou;
4292
4293 while (1) {
4294 if (dlm_locking_stopped(ls)) {
4295 log_debug(ls, "recover_waiters_post aborted");
4296 error = -EINTR;
4297 break;
4298 }
4299
4300 lkb = find_resend_waiter(ls);
4301 if (!lkb)
4302 break;
4303
4304 r = lkb->lkb_resource;
4305 hold_rsb(r);
4306 lock_rsb(r);
4307
4308 mstype = lkb->lkb_wait_type;
4309 oc = is_overlap_cancel(lkb);
4310 ou = is_overlap_unlock(lkb);
4311 err = 0;
4312
4313 log_debug(ls, "recover_waiter %x nodeid %d msg %d r_nodeid %d",
4314 lkb->lkb_id, lkb->lkb_nodeid, mstype, r->res_nodeid);
4315
4316 /* At this point we assume that we won't get a reply to any
4317 previous op or overlap op on this lock. First, do a big
4318 remove_from_waiters() for all previous ops. */
4319
4320 lkb->lkb_flags &= ~DLM_IFL_RESEND;
4321 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4322 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4323 lkb->lkb_wait_type = 0;
4324 lkb->lkb_wait_count = 0;
4325 mutex_lock(&ls->ls_waiters_mutex);
4326 list_del_init(&lkb->lkb_wait_reply);
4327 mutex_unlock(&ls->ls_waiters_mutex);
4328 unhold_lkb(lkb); /* for waiters list */
4329
4330 if (oc || ou) {
4331 /* do an unlock or cancel instead of resending */
4332 switch (mstype) {
4333 case DLM_MSG_LOOKUP:
4334 case DLM_MSG_REQUEST:
4335 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
4336 -DLM_ECANCEL);
4337 unhold_lkb(lkb); /* undoes create_lkb() */
4338 break;
4339 case DLM_MSG_CONVERT:
4340 if (oc) {
4341 queue_cast(r, lkb, -DLM_ECANCEL);
4342 } else {
4343 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
4344 _unlock_lock(r, lkb);
4345 }
4346 break;
4347 default:
4348 err = 1;
4349 }
4350 } else {
4351 switch (mstype) {
4352 case DLM_MSG_LOOKUP:
4353 case DLM_MSG_REQUEST:
4354 _request_lock(r, lkb);
4355 if (is_master(r))
4356 confirm_master(r, 0);
4357 break;
4358 case DLM_MSG_CONVERT:
4359 _convert_lock(r, lkb);
4360 break;
4361 default:
4362 err = 1;
4363 }
4364 }
4365
4366 if (err)
4367 log_error(ls, "recover_waiters_post %x %d %x %d %d",
4368 lkb->lkb_id, mstype, lkb->lkb_flags, oc, ou);
4369 unlock_rsb(r);
4370 put_rsb(r);
4371 dlm_put_lkb(lkb);
4372 }
4373
4374 return error;
4375}
4376
4377static void purge_queue(struct dlm_rsb *r, struct list_head *queue,
4378 int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb))
4379{
4380 struct dlm_ls *ls = r->res_ls;
4381 struct dlm_lkb *lkb, *safe;
4382
4383 list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) {
4384 if (test(ls, lkb)) {
4385 rsb_set_flag(r, RSB_LOCKS_PURGED);
4386 del_lkb(r, lkb);
4387 /* this put should free the lkb */
4388 if (!dlm_put_lkb(lkb))
4389 log_error(ls, "purged lkb not released");
4390 }
4391 }
4392}
4393
4394static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4395{
4396 return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid));
4397}
4398
4399static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4400{
4401 return is_master_copy(lkb);
4402}
4403
4404static void purge_dead_locks(struct dlm_rsb *r)
4405{
4406 purge_queue(r, &r->res_grantqueue, &purge_dead_test);
4407 purge_queue(r, &r->res_convertqueue, &purge_dead_test);
4408 purge_queue(r, &r->res_waitqueue, &purge_dead_test);
4409}
4410
4411void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
4412{
4413 purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test);
4414 purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test);
4415 purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test);
4416}
4417
4418/* Get rid of locks held by nodes that are gone. */
4419
4420int dlm_purge_locks(struct dlm_ls *ls)
4421{
4422 struct dlm_rsb *r;
4423
4424 log_debug(ls, "dlm_purge_locks");
4425
4426 down_write(&ls->ls_root_sem);
4427 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
4428 hold_rsb(r);
4429 lock_rsb(r);
4430 if (is_master(r))
4431 purge_dead_locks(r);
4432 unlock_rsb(r);
4433 unhold_rsb(r);
4434
4435 schedule();
4436 }
4437 up_write(&ls->ls_root_sem);
4438
4439 return 0;
4440}
4441
4442static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
4443{
4444 struct dlm_rsb *r, *r_ret = NULL;
4445
4446 spin_lock(&ls->ls_rsbtbl[bucket].lock);
4447 list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list, res_hashchain) {
4448 if (!rsb_flag(r, RSB_LOCKS_PURGED))
4449 continue;
4450 hold_rsb(r);
4451 rsb_clear_flag(r, RSB_LOCKS_PURGED);
4452 r_ret = r;
4453 break;
4454 }
4455 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
4456 return r_ret;
4457}
4458
4459void dlm_grant_after_purge(struct dlm_ls *ls)
4460{
4461 struct dlm_rsb *r;
4462 int bucket = 0;
4463
4464 while (1) {
4465 r = find_purged_rsb(ls, bucket);
4466 if (!r) {
4467 if (bucket == ls->ls_rsbtbl_size - 1)
4468 break;
4469 bucket++;
4470 continue;
4471 }
4472 lock_rsb(r);
4473 if (is_master(r)) {
4474 grant_pending_locks(r);
4475 confirm_master(r, 0);
4476 }
4477 unlock_rsb(r);
4478 put_rsb(r);
4479 schedule();
4480 }
4481}
4482
4483static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
4484 uint32_t remid)
4485{
4486 struct dlm_lkb *lkb;
4487
4488 list_for_each_entry(lkb, head, lkb_statequeue) {
4489 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
4490 return lkb;
4491 }
4492 return NULL;
4493}
4494
4495static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
4496 uint32_t remid)
4497{
4498 struct dlm_lkb *lkb;
4499
4500 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
4501 if (lkb)
4502 return lkb;
4503 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
4504 if (lkb)
4505 return lkb;
4506 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
4507 if (lkb)
4508 return lkb;
4509 return NULL;
4510}
4511
4512/* needs at least dlm_rcom + rcom_lock */
4513static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
4514 struct dlm_rsb *r, struct dlm_rcom *rc)
4515{
4516 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4517
4518 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
4519 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
4520 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
4521 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
4522 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
4523 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4524 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
4525 lkb->lkb_rqmode = rl->rl_rqmode;
4526 lkb->lkb_grmode = rl->rl_grmode;
4527 /* don't set lkb_status because add_lkb wants to itself */
4528
4529 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
4530 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
4531
4532 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
4533 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
4534 sizeof(struct rcom_lock);
4535 if (lvblen > ls->ls_lvblen)
4536 return -EINVAL;
4537 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
4538 if (!lkb->lkb_lvbptr)
4539 return -ENOMEM;
4540 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
4541 }
4542
4543 /* Conversions between PR and CW (middle modes) need special handling.
4544 The real granted mode of these converting locks cannot be determined
4545 until all locks have been rebuilt on the rsb (recover_conversion) */
4546
4547 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
4548 middle_conversion(lkb)) {
4549 rl->rl_status = DLM_LKSTS_CONVERT;
4550 lkb->lkb_grmode = DLM_LOCK_IV;
4551 rsb_set_flag(r, RSB_RECOVER_CONVERT);
4552 }
4553
4554 return 0;
4555}
4556
4557/* This lkb may have been recovered in a previous aborted recovery so we need
4558 to check if the rsb already has an lkb with the given remote nodeid/lkid.
4559 If so we just send back a standard reply. If not, we create a new lkb with
4560 the given values and send back our lkid. We send back our lkid by sending
4561 back the rcom_lock struct we got but with the remid field filled in. */
4562
4563/* needs at least dlm_rcom + rcom_lock */
4564int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4565{
4566 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4567 struct dlm_rsb *r;
4568 struct dlm_lkb *lkb;
4569 int error;
4570
4571 if (rl->rl_parent_lkid) {
4572 error = -EOPNOTSUPP;
4573 goto out;
4574 }
4575
4576 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
4577 R_MASTER, &r);
4578 if (error)
4579 goto out;
4580
4581 lock_rsb(r);
4582
4583 lkb = search_remid(r, rc->rc_header.h_nodeid, le32_to_cpu(rl->rl_lkid));
4584 if (lkb) {
4585 error = -EEXIST;
4586 goto out_remid;
4587 }
4588
4589 error = create_lkb(ls, &lkb);
4590 if (error)
4591 goto out_unlock;
4592
4593 error = receive_rcom_lock_args(ls, lkb, r, rc);
4594 if (error) {
4595 __put_lkb(ls, lkb);
4596 goto out_unlock;
4597 }
4598
4599 attach_lkb(r, lkb);
4600 add_lkb(r, lkb, rl->rl_status);
4601 error = 0;
4602
4603 out_remid:
4604 /* this is the new value returned to the lock holder for
4605 saving in its process-copy lkb */
4606 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
4607
4608 out_unlock:
4609 unlock_rsb(r);
4610 put_rsb(r);
4611 out:
4612 if (error)
4613 log_debug(ls, "recover_master_copy %d %x", error,
4614 le32_to_cpu(rl->rl_lkid));
4615 rl->rl_result = cpu_to_le32(error);
4616 return error;
4617}
4618
4619/* needs at least dlm_rcom + rcom_lock */
4620int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4621{
4622 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4623 struct dlm_rsb *r;
4624 struct dlm_lkb *lkb;
4625 int error;
4626
4627 error = find_lkb(ls, le32_to_cpu(rl->rl_lkid), &lkb);
4628 if (error) {
4629 log_error(ls, "recover_process_copy no lkid %x",
4630 le32_to_cpu(rl->rl_lkid));
4631 return error;
4632 }
4633
4634 DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
4635
4636 error = le32_to_cpu(rl->rl_result);
4637
4638 r = lkb->lkb_resource;
4639 hold_rsb(r);
4640 lock_rsb(r);
4641
4642 switch (error) {
4643 case -EBADR:
4644 /* There's a chance the new master received our lock before
4645 dlm_recover_master_reply(), this wouldn't happen if we did
4646 a barrier between recover_masters and recover_locks. */
4647 log_debug(ls, "master copy not ready %x r %lx %s", lkb->lkb_id,
4648 (unsigned long)r, r->res_name);
4649 dlm_send_rcom_lock(r, lkb);
4650 goto out;
4651 case -EEXIST:
4652 log_debug(ls, "master copy exists %x", lkb->lkb_id);
4653 /* fall through */
4654 case 0:
4655 lkb->lkb_remid = le32_to_cpu(rl->rl_remid);
4656 break;
4657 default:
4658 log_error(ls, "dlm_recover_process_copy unknown error %d %x",
4659 error, lkb->lkb_id);
4660 }
4661
4662 /* an ack for dlm_recover_locks() which waits for replies from
4663 all the locks it sends to new masters */
4664 dlm_recovered_lock(r);
4665 out:
4666 unlock_rsb(r);
4667 put_rsb(r);
4668 dlm_put_lkb(lkb);
4669
4670 return 0;
4671}
4672
4673int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
4674 int mode, uint32_t flags, void *name, unsigned int namelen,
4675 unsigned long timeout_cs)
4676{
4677 struct dlm_lkb *lkb;
4678 struct dlm_args args;
4679 int error;
4680
4681 dlm_lock_recovery(ls);
4682
4683 error = create_lkb(ls, &lkb);
4684 if (error) {
4685 kfree(ua);
4686 goto out;
4687 }
4688
4689 if (flags & DLM_LKF_VALBLK) {
4690 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
4691 if (!ua->lksb.sb_lvbptr) {
4692 kfree(ua);
4693 __put_lkb(ls, lkb);
4694 error = -ENOMEM;
4695 goto out;
4696 }
4697 }
4698
4699 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
4700 When DLM_IFL_USER is set, the dlm knows that this is a userspace
4701 lock and that lkb_astparam is the dlm_user_args structure. */
4702
4703 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
4704 fake_astfn, ua, fake_bastfn, &args);
4705 lkb->lkb_flags |= DLM_IFL_USER;
4706
4707 if (error) {
4708 __put_lkb(ls, lkb);
4709 goto out;
4710 }
4711
4712 error = request_lock(ls, lkb, name, namelen, &args);
4713
4714 switch (error) {
4715 case 0:
4716 break;
4717 case -EINPROGRESS:
4718 error = 0;
4719 break;
4720 case -EAGAIN:
4721 error = 0;
4722 /* fall through */
4723 default:
4724 __put_lkb(ls, lkb);
4725 goto out;
4726 }
4727
4728 /* add this new lkb to the per-process list of locks */
4729 spin_lock(&ua->proc->locks_spin);
4730 hold_lkb(lkb);
4731 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
4732 spin_unlock(&ua->proc->locks_spin);
4733 out:
4734 dlm_unlock_recovery(ls);
4735 return error;
4736}
4737
4738int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4739 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
4740 unsigned long timeout_cs)
4741{
4742 struct dlm_lkb *lkb;
4743 struct dlm_args args;
4744 struct dlm_user_args *ua;
4745 int error;
4746
4747 dlm_lock_recovery(ls);
4748
4749 error = find_lkb(ls, lkid, &lkb);
4750 if (error)
4751 goto out;
4752
4753 /* user can change the params on its lock when it converts it, or
4754 add an lvb that didn't exist before */
4755
4756 ua = lkb->lkb_ua;
4757
4758 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
4759 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
4760 if (!ua->lksb.sb_lvbptr) {
4761 error = -ENOMEM;
4762 goto out_put;
4763 }
4764 }
4765 if (lvb_in && ua->lksb.sb_lvbptr)
4766 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
4767
4768 ua->xid = ua_tmp->xid;
4769 ua->castparam = ua_tmp->castparam;
4770 ua->castaddr = ua_tmp->castaddr;
4771 ua->bastparam = ua_tmp->bastparam;
4772 ua->bastaddr = ua_tmp->bastaddr;
4773 ua->user_lksb = ua_tmp->user_lksb;
4774
4775 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
4776 fake_astfn, ua, fake_bastfn, &args);
4777 if (error)
4778 goto out_put;
4779
4780 error = convert_lock(ls, lkb, &args);
4781
4782 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
4783 error = 0;
4784 out_put:
4785 dlm_put_lkb(lkb);
4786 out:
4787 dlm_unlock_recovery(ls);
4788 kfree(ua_tmp);
4789 return error;
4790}
4791
4792int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4793 uint32_t flags, uint32_t lkid, char *lvb_in)
4794{
4795 struct dlm_lkb *lkb;
4796 struct dlm_args args;
4797 struct dlm_user_args *ua;
4798 int error;
4799
4800 dlm_lock_recovery(ls);
4801
4802 error = find_lkb(ls, lkid, &lkb);
4803 if (error)
4804 goto out;
4805
4806 ua = lkb->lkb_ua;
4807
4808 if (lvb_in && ua->lksb.sb_lvbptr)
4809 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
4810 if (ua_tmp->castparam)
4811 ua->castparam = ua_tmp->castparam;
4812 ua->user_lksb = ua_tmp->user_lksb;
4813
4814 error = set_unlock_args(flags, ua, &args);
4815 if (error)
4816 goto out_put;
4817
4818 error = unlock_lock(ls, lkb, &args);
4819
4820 if (error == -DLM_EUNLOCK)
4821 error = 0;
4822 /* from validate_unlock_args() */
4823 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
4824 error = 0;
4825 if (error)
4826 goto out_put;
4827
4828 spin_lock(&ua->proc->locks_spin);
4829 /* dlm_user_add_cb() may have already taken lkb off the proc list */
4830 if (!list_empty(&lkb->lkb_ownqueue))
4831 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
4832 spin_unlock(&ua->proc->locks_spin);
4833 out_put:
4834 dlm_put_lkb(lkb);
4835 out:
4836 dlm_unlock_recovery(ls);
4837 kfree(ua_tmp);
4838 return error;
4839}
4840
4841int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4842 uint32_t flags, uint32_t lkid)
4843{
4844 struct dlm_lkb *lkb;
4845 struct dlm_args args;
4846 struct dlm_user_args *ua;
4847 int error;
4848
4849 dlm_lock_recovery(ls);
4850
4851 error = find_lkb(ls, lkid, &lkb);
4852 if (error)
4853 goto out;
4854
4855 ua = lkb->lkb_ua;
4856 if (ua_tmp->castparam)
4857 ua->castparam = ua_tmp->castparam;
4858 ua->user_lksb = ua_tmp->user_lksb;
4859
4860 error = set_unlock_args(flags, ua, &args);
4861 if (error)
4862 goto out_put;
4863
4864 error = cancel_lock(ls, lkb, &args);
4865
4866 if (error == -DLM_ECANCEL)
4867 error = 0;
4868 /* from validate_unlock_args() */
4869 if (error == -EBUSY)
4870 error = 0;
4871 out_put:
4872 dlm_put_lkb(lkb);
4873 out:
4874 dlm_unlock_recovery(ls);
4875 kfree(ua_tmp);
4876 return error;
4877}
4878
4879int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
4880{
4881 struct dlm_lkb *lkb;
4882 struct dlm_args args;
4883 struct dlm_user_args *ua;
4884 struct dlm_rsb *r;
4885 int error;
4886
4887 dlm_lock_recovery(ls);
4888
4889 error = find_lkb(ls, lkid, &lkb);
4890 if (error)
4891 goto out;
4892
4893 ua = lkb->lkb_ua;
4894
4895 error = set_unlock_args(flags, ua, &args);
4896 if (error)
4897 goto out_put;
4898
4899 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
4900
4901 r = lkb->lkb_resource;
4902 hold_rsb(r);
4903 lock_rsb(r);
4904
4905 error = validate_unlock_args(lkb, &args);
4906 if (error)
4907 goto out_r;
4908 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
4909
4910 error = _cancel_lock(r, lkb);
4911 out_r:
4912 unlock_rsb(r);
4913 put_rsb(r);
4914
4915 if (error == -DLM_ECANCEL)
4916 error = 0;
4917 /* from validate_unlock_args() */
4918 if (error == -EBUSY)
4919 error = 0;
4920 out_put:
4921 dlm_put_lkb(lkb);
4922 out:
4923 dlm_unlock_recovery(ls);
4924 return error;
4925}
4926
4927/* lkb's that are removed from the waiters list by revert are just left on the
4928 orphans list with the granted orphan locks, to be freed by purge */
4929
4930static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4931{
4932 struct dlm_args args;
4933 int error;
4934
4935 hold_lkb(lkb);
4936 mutex_lock(&ls->ls_orphans_mutex);
4937 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
4938 mutex_unlock(&ls->ls_orphans_mutex);
4939
4940 set_unlock_args(0, lkb->lkb_ua, &args);
4941
4942 error = cancel_lock(ls, lkb, &args);
4943 if (error == -DLM_ECANCEL)
4944 error = 0;
4945 return error;
4946}
4947
4948/* The force flag allows the unlock to go ahead even if the lkb isn't granted.
4949 Regardless of what rsb queue the lock is on, it's removed and freed. */
4950
4951static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4952{
4953 struct dlm_args args;
4954 int error;
4955
4956 set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
4957
4958 error = unlock_lock(ls, lkb, &args);
4959 if (error == -DLM_EUNLOCK)
4960 error = 0;
4961 return error;
4962}
4963
4964/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
4965 (which does lock_rsb) due to deadlock with receiving a message that does
4966 lock_rsb followed by dlm_user_add_cb() */
4967
4968static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
4969 struct dlm_user_proc *proc)
4970{
4971 struct dlm_lkb *lkb = NULL;
4972
4973 mutex_lock(&ls->ls_clear_proc_locks);
4974 if (list_empty(&proc->locks))
4975 goto out;
4976
4977 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
4978 list_del_init(&lkb->lkb_ownqueue);
4979
4980 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
4981 lkb->lkb_flags |= DLM_IFL_ORPHAN;
4982 else
4983 lkb->lkb_flags |= DLM_IFL_DEAD;
4984 out:
4985 mutex_unlock(&ls->ls_clear_proc_locks);
4986 return lkb;
4987}
4988
4989/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
4990 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
4991 which we clear here. */
4992
4993/* proc CLOSING flag is set so no more device_reads should look at proc->asts
4994 list, and no more device_writes should add lkb's to proc->locks list; so we
4995 shouldn't need to take asts_spin or locks_spin here. this assumes that
4996 device reads/writes/closes are serialized -- FIXME: we may need to serialize
4997 them ourself. */
4998
4999void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
5000{
5001 struct dlm_lkb *lkb, *safe;
5002
5003 dlm_lock_recovery(ls);
5004
5005 while (1) {
5006 lkb = del_proc_lock(ls, proc);
5007 if (!lkb)
5008 break;
5009 del_timeout(lkb);
5010 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
5011 orphan_proc_lock(ls, lkb);
5012 else
5013 unlock_proc_lock(ls, lkb);
5014
5015 /* this removes the reference for the proc->locks list
5016 added by dlm_user_request, it may result in the lkb
5017 being freed */
5018
5019 dlm_put_lkb(lkb);
5020 }
5021
5022 mutex_lock(&ls->ls_clear_proc_locks);
5023
5024 /* in-progress unlocks */
5025 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
5026 list_del_init(&lkb->lkb_ownqueue);
5027 lkb->lkb_flags |= DLM_IFL_DEAD;
5028 dlm_put_lkb(lkb);
5029 }
5030
5031 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
5032 memset(&lkb->lkb_callbacks, 0,
5033 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
5034 list_del_init(&lkb->lkb_cb_list);
5035 dlm_put_lkb(lkb);
5036 }
5037
5038 mutex_unlock(&ls->ls_clear_proc_locks);
5039 dlm_unlock_recovery(ls);
5040}
5041
5042static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
5043{
5044 struct dlm_lkb *lkb, *safe;
5045
5046 while (1) {
5047 lkb = NULL;
5048 spin_lock(&proc->locks_spin);
5049 if (!list_empty(&proc->locks)) {
5050 lkb = list_entry(proc->locks.next, struct dlm_lkb,
5051 lkb_ownqueue);
5052 list_del_init(&lkb->lkb_ownqueue);
5053 }
5054 spin_unlock(&proc->locks_spin);
5055
5056 if (!lkb)
5057 break;
5058
5059 lkb->lkb_flags |= DLM_IFL_DEAD;
5060 unlock_proc_lock(ls, lkb);
5061 dlm_put_lkb(lkb); /* ref from proc->locks list */
5062 }
5063
5064 spin_lock(&proc->locks_spin);
5065 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
5066 list_del_init(&lkb->lkb_ownqueue);
5067 lkb->lkb_flags |= DLM_IFL_DEAD;
5068 dlm_put_lkb(lkb);
5069 }
5070 spin_unlock(&proc->locks_spin);
5071
5072 spin_lock(&proc->asts_spin);
5073 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
5074 memset(&lkb->lkb_callbacks, 0,
5075 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
5076 list_del_init(&lkb->lkb_cb_list);
5077 dlm_put_lkb(lkb);
5078 }
5079 spin_unlock(&proc->asts_spin);
5080}
5081
5082/* pid of 0 means purge all orphans */
5083
5084static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
5085{
5086 struct dlm_lkb *lkb, *safe;
5087
5088 mutex_lock(&ls->ls_orphans_mutex);
5089 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
5090 if (pid && lkb->lkb_ownpid != pid)
5091 continue;
5092 unlock_proc_lock(ls, lkb);
5093 list_del_init(&lkb->lkb_ownqueue);
5094 dlm_put_lkb(lkb);
5095 }
5096 mutex_unlock(&ls->ls_orphans_mutex);
5097}
5098
5099static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
5100{
5101 struct dlm_message *ms;
5102 struct dlm_mhandle *mh;
5103 int error;
5104
5105 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
5106 DLM_MSG_PURGE, &ms, &mh);
5107 if (error)
5108 return error;
5109 ms->m_nodeid = nodeid;
5110 ms->m_pid = pid;
5111
5112 return send_message(mh, ms);
5113}
5114
5115int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
5116 int nodeid, int pid)
5117{
5118 int error = 0;
5119
5120 if (nodeid != dlm_our_nodeid()) {
5121 error = send_purge(ls, nodeid, pid);
5122 } else {
5123 dlm_lock_recovery(ls);
5124 if (pid == current->pid)
5125 purge_proc_locks(ls, proc);
5126 else
5127 do_purge(ls, nodeid, pid);
5128 dlm_unlock_recovery(ls);
5129 }
5130 return error;
5131}
5132
1// SPDX-License-Identifier: GPL-2.0-only
2/******************************************************************************
3*******************************************************************************
4**
5** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
6**
7**
8*******************************************************************************
9******************************************************************************/
10
11/* Central locking logic has four stages:
12
13 dlm_lock()
14 dlm_unlock()
15
16 request_lock(ls, lkb)
17 convert_lock(ls, lkb)
18 unlock_lock(ls, lkb)
19 cancel_lock(ls, lkb)
20
21 _request_lock(r, lkb)
22 _convert_lock(r, lkb)
23 _unlock_lock(r, lkb)
24 _cancel_lock(r, lkb)
25
26 do_request(r, lkb)
27 do_convert(r, lkb)
28 do_unlock(r, lkb)
29 do_cancel(r, lkb)
30
31 Stage 1 (lock, unlock) is mainly about checking input args and
32 splitting into one of the four main operations:
33
34 dlm_lock = request_lock
35 dlm_lock+CONVERT = convert_lock
36 dlm_unlock = unlock_lock
37 dlm_unlock+CANCEL = cancel_lock
38
39 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
40 provided to the next stage.
41
42 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
43 When remote, it calls send_xxxx(), when local it calls do_xxxx().
44
45 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
46 given rsb and lkb and queues callbacks.
47
48 For remote operations, send_xxxx() results in the corresponding do_xxxx()
49 function being executed on the remote node. The connecting send/receive
50 calls on local (L) and remote (R) nodes:
51
52 L: send_xxxx() -> R: receive_xxxx()
53 R: do_xxxx()
54 L: receive_xxxx_reply() <- R: send_xxxx_reply()
55*/
56#include <trace/events/dlm.h>
57
58#include <linux/types.h>
59#include <linux/rbtree.h>
60#include <linux/slab.h>
61#include "dlm_internal.h"
62#include <linux/dlm_device.h>
63#include "memory.h"
64#include "midcomms.h"
65#include "requestqueue.h"
66#include "util.h"
67#include "dir.h"
68#include "member.h"
69#include "lockspace.h"
70#include "ast.h"
71#include "lock.h"
72#include "rcom.h"
73#include "recover.h"
74#include "lvb_table.h"
75#include "user.h"
76#include "config.h"
77
78static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
82static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
83static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
84static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
85static int send_remove(struct dlm_rsb *r);
86static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
87static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
88static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
89 const struct dlm_message *ms, bool local);
90static int receive_extralen(const struct dlm_message *ms);
91static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
92static void toss_rsb(struct kref *kref);
93
94/*
95 * Lock compatibilty matrix - thanks Steve
96 * UN = Unlocked state. Not really a state, used as a flag
97 * PD = Padding. Used to make the matrix a nice power of two in size
98 * Other states are the same as the VMS DLM.
99 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
100 */
101
102static const int __dlm_compat_matrix[8][8] = {
103 /* UN NL CR CW PR PW EX PD */
104 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
105 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
106 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
107 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
108 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
109 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
110 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
111 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
112};
113
114/*
115 * This defines the direction of transfer of LVB data.
116 * Granted mode is the row; requested mode is the column.
117 * Usage: matrix[grmode+1][rqmode+1]
118 * 1 = LVB is returned to the caller
119 * 0 = LVB is written to the resource
120 * -1 = nothing happens to the LVB
121 */
122
123const int dlm_lvb_operations[8][8] = {
124 /* UN NL CR CW PR PW EX PD*/
125 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
126 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
127 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
128 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
129 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
130 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
131 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
132 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
133};
134
135#define modes_compat(gr, rq) \
136 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
137
138int dlm_modes_compat(int mode1, int mode2)
139{
140 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
141}
142
143/*
144 * Compatibility matrix for conversions with QUECVT set.
145 * Granted mode is the row; requested mode is the column.
146 * Usage: matrix[grmode+1][rqmode+1]
147 */
148
149static const int __quecvt_compat_matrix[8][8] = {
150 /* UN NL CR CW PR PW EX PD */
151 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
152 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
153 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
154 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
155 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
156 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
157 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
158 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
159};
160
161void dlm_print_lkb(struct dlm_lkb *lkb)
162{
163 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
164 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
165 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
166 dlm_iflags_val(lkb), lkb->lkb_status, lkb->lkb_rqmode,
167 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
168 (unsigned long long)lkb->lkb_recover_seq);
169}
170
171static void dlm_print_rsb(struct dlm_rsb *r)
172{
173 printk(KERN_ERR "rsb: nodeid %d master %d dir %d flags %lx first %x "
174 "rlc %d name %s\n",
175 r->res_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
176 r->res_flags, r->res_first_lkid, r->res_recover_locks_count,
177 r->res_name);
178}
179
180void dlm_dump_rsb(struct dlm_rsb *r)
181{
182 struct dlm_lkb *lkb;
183
184 dlm_print_rsb(r);
185
186 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
187 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
188 printk(KERN_ERR "rsb lookup list\n");
189 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
190 dlm_print_lkb(lkb);
191 printk(KERN_ERR "rsb grant queue:\n");
192 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
193 dlm_print_lkb(lkb);
194 printk(KERN_ERR "rsb convert queue:\n");
195 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
196 dlm_print_lkb(lkb);
197 printk(KERN_ERR "rsb wait queue:\n");
198 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
199 dlm_print_lkb(lkb);
200}
201
202/* Threads cannot use the lockspace while it's being recovered */
203
204static inline void dlm_lock_recovery(struct dlm_ls *ls)
205{
206 down_read(&ls->ls_in_recovery);
207}
208
209void dlm_unlock_recovery(struct dlm_ls *ls)
210{
211 up_read(&ls->ls_in_recovery);
212}
213
214int dlm_lock_recovery_try(struct dlm_ls *ls)
215{
216 return down_read_trylock(&ls->ls_in_recovery);
217}
218
219static inline int can_be_queued(struct dlm_lkb *lkb)
220{
221 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
222}
223
224static inline int force_blocking_asts(struct dlm_lkb *lkb)
225{
226 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
227}
228
229static inline int is_demoted(struct dlm_lkb *lkb)
230{
231 return test_bit(DLM_SBF_DEMOTED_BIT, &lkb->lkb_sbflags);
232}
233
234static inline int is_altmode(struct dlm_lkb *lkb)
235{
236 return test_bit(DLM_SBF_ALTMODE_BIT, &lkb->lkb_sbflags);
237}
238
239static inline int is_granted(struct dlm_lkb *lkb)
240{
241 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
242}
243
244static inline int is_remote(struct dlm_rsb *r)
245{
246 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
247 return !!r->res_nodeid;
248}
249
250static inline int is_process_copy(struct dlm_lkb *lkb)
251{
252 return lkb->lkb_nodeid &&
253 !test_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags);
254}
255
256static inline int is_master_copy(struct dlm_lkb *lkb)
257{
258 return test_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags);
259}
260
261static inline int middle_conversion(struct dlm_lkb *lkb)
262{
263 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
264 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
265 return 1;
266 return 0;
267}
268
269static inline int down_conversion(struct dlm_lkb *lkb)
270{
271 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
272}
273
274static inline int is_overlap_unlock(struct dlm_lkb *lkb)
275{
276 return test_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
277}
278
279static inline int is_overlap_cancel(struct dlm_lkb *lkb)
280{
281 return test_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
282}
283
284static inline int is_overlap(struct dlm_lkb *lkb)
285{
286 return test_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags) ||
287 test_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
288}
289
290static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
291{
292 if (is_master_copy(lkb))
293 return;
294
295 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
296
297 if (rv == -DLM_ECANCEL &&
298 test_and_clear_bit(DLM_IFL_DEADLOCK_CANCEL_BIT, &lkb->lkb_iflags))
299 rv = -EDEADLK;
300
301 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, dlm_sbflags_val(lkb));
302}
303
304static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
305{
306 queue_cast(r, lkb,
307 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
308}
309
310static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
311{
312 if (is_master_copy(lkb)) {
313 send_bast(r, lkb, rqmode);
314 } else {
315 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
316 }
317}
318
319/*
320 * Basic operations on rsb's and lkb's
321 */
322
323/* This is only called to add a reference when the code already holds
324 a valid reference to the rsb, so there's no need for locking. */
325
326static inline void hold_rsb(struct dlm_rsb *r)
327{
328 kref_get(&r->res_ref);
329}
330
331void dlm_hold_rsb(struct dlm_rsb *r)
332{
333 hold_rsb(r);
334}
335
336/* When all references to the rsb are gone it's transferred to
337 the tossed list for later disposal. */
338
339static void put_rsb(struct dlm_rsb *r)
340{
341 struct dlm_ls *ls = r->res_ls;
342 uint32_t bucket = r->res_bucket;
343 int rv;
344
345 rv = kref_put_lock(&r->res_ref, toss_rsb,
346 &ls->ls_rsbtbl[bucket].lock);
347 if (rv)
348 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
349}
350
351void dlm_put_rsb(struct dlm_rsb *r)
352{
353 put_rsb(r);
354}
355
356static int pre_rsb_struct(struct dlm_ls *ls)
357{
358 struct dlm_rsb *r1, *r2;
359 int count = 0;
360
361 spin_lock(&ls->ls_new_rsb_spin);
362 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
363 spin_unlock(&ls->ls_new_rsb_spin);
364 return 0;
365 }
366 spin_unlock(&ls->ls_new_rsb_spin);
367
368 r1 = dlm_allocate_rsb(ls);
369 r2 = dlm_allocate_rsb(ls);
370
371 spin_lock(&ls->ls_new_rsb_spin);
372 if (r1) {
373 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
374 ls->ls_new_rsb_count++;
375 }
376 if (r2) {
377 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
378 ls->ls_new_rsb_count++;
379 }
380 count = ls->ls_new_rsb_count;
381 spin_unlock(&ls->ls_new_rsb_spin);
382
383 if (!count)
384 return -ENOMEM;
385 return 0;
386}
387
388/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
389 unlock any spinlocks, go back and call pre_rsb_struct again.
390 Otherwise, take an rsb off the list and return it. */
391
392static int get_rsb_struct(struct dlm_ls *ls, const void *name, int len,
393 struct dlm_rsb **r_ret)
394{
395 struct dlm_rsb *r;
396 int count;
397
398 spin_lock(&ls->ls_new_rsb_spin);
399 if (list_empty(&ls->ls_new_rsb)) {
400 count = ls->ls_new_rsb_count;
401 spin_unlock(&ls->ls_new_rsb_spin);
402 log_debug(ls, "find_rsb retry %d %d %s",
403 count, dlm_config.ci_new_rsb_count,
404 (const char *)name);
405 return -EAGAIN;
406 }
407
408 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
409 list_del(&r->res_hashchain);
410 /* Convert the empty list_head to a NULL rb_node for tree usage: */
411 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
412 ls->ls_new_rsb_count--;
413 spin_unlock(&ls->ls_new_rsb_spin);
414
415 r->res_ls = ls;
416 r->res_length = len;
417 memcpy(r->res_name, name, len);
418 mutex_init(&r->res_mutex);
419
420 INIT_LIST_HEAD(&r->res_lookup);
421 INIT_LIST_HEAD(&r->res_grantqueue);
422 INIT_LIST_HEAD(&r->res_convertqueue);
423 INIT_LIST_HEAD(&r->res_waitqueue);
424 INIT_LIST_HEAD(&r->res_root_list);
425 INIT_LIST_HEAD(&r->res_recover_list);
426
427 *r_ret = r;
428 return 0;
429}
430
431static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
432{
433 char maxname[DLM_RESNAME_MAXLEN];
434
435 memset(maxname, 0, DLM_RESNAME_MAXLEN);
436 memcpy(maxname, name, nlen);
437 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
438}
439
440int dlm_search_rsb_tree(struct rb_root *tree, const void *name, int len,
441 struct dlm_rsb **r_ret)
442{
443 struct rb_node *node = tree->rb_node;
444 struct dlm_rsb *r;
445 int rc;
446
447 while (node) {
448 r = rb_entry(node, struct dlm_rsb, res_hashnode);
449 rc = rsb_cmp(r, name, len);
450 if (rc < 0)
451 node = node->rb_left;
452 else if (rc > 0)
453 node = node->rb_right;
454 else
455 goto found;
456 }
457 *r_ret = NULL;
458 return -EBADR;
459
460 found:
461 *r_ret = r;
462 return 0;
463}
464
465static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
466{
467 struct rb_node **newn = &tree->rb_node;
468 struct rb_node *parent = NULL;
469 int rc;
470
471 while (*newn) {
472 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
473 res_hashnode);
474
475 parent = *newn;
476 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
477 if (rc < 0)
478 newn = &parent->rb_left;
479 else if (rc > 0)
480 newn = &parent->rb_right;
481 else {
482 log_print("rsb_insert match");
483 dlm_dump_rsb(rsb);
484 dlm_dump_rsb(cur);
485 return -EEXIST;
486 }
487 }
488
489 rb_link_node(&rsb->res_hashnode, parent, newn);
490 rb_insert_color(&rsb->res_hashnode, tree);
491 return 0;
492}
493
494/*
495 * Find rsb in rsbtbl and potentially create/add one
496 *
497 * Delaying the release of rsb's has a similar benefit to applications keeping
498 * NL locks on an rsb, but without the guarantee that the cached master value
499 * will still be valid when the rsb is reused. Apps aren't always smart enough
500 * to keep NL locks on an rsb that they may lock again shortly; this can lead
501 * to excessive master lookups and removals if we don't delay the release.
502 *
503 * Searching for an rsb means looking through both the normal list and toss
504 * list. When found on the toss list the rsb is moved to the normal list with
505 * ref count of 1; when found on normal list the ref count is incremented.
506 *
507 * rsb's on the keep list are being used locally and refcounted.
508 * rsb's on the toss list are not being used locally, and are not refcounted.
509 *
510 * The toss list rsb's were either
511 * - previously used locally but not any more (were on keep list, then
512 * moved to toss list when last refcount dropped)
513 * - created and put on toss list as a directory record for a lookup
514 * (we are the dir node for the res, but are not using the res right now,
515 * but some other node is)
516 *
517 * The purpose of find_rsb() is to return a refcounted rsb for local use.
518 * So, if the given rsb is on the toss list, it is moved to the keep list
519 * before being returned.
520 *
521 * toss_rsb() happens when all local usage of the rsb is done, i.e. no
522 * more refcounts exist, so the rsb is moved from the keep list to the
523 * toss list.
524 *
525 * rsb's on both keep and toss lists are used for doing a name to master
526 * lookups. rsb's that are in use locally (and being refcounted) are on
527 * the keep list, rsb's that are not in use locally (not refcounted) and
528 * only exist for name/master lookups are on the toss list.
529 *
530 * rsb's on the toss list who's dir_nodeid is not local can have stale
531 * name/master mappings. So, remote requests on such rsb's can potentially
532 * return with an error, which means the mapping is stale and needs to
533 * be updated with a new lookup. (The idea behind MASTER UNCERTAIN and
534 * first_lkid is to keep only a single outstanding request on an rsb
535 * while that rsb has a potentially stale master.)
536 */
537
538static int find_rsb_dir(struct dlm_ls *ls, const void *name, int len,
539 uint32_t hash, uint32_t b,
540 int dir_nodeid, int from_nodeid,
541 unsigned int flags, struct dlm_rsb **r_ret)
542{
543 struct dlm_rsb *r = NULL;
544 int our_nodeid = dlm_our_nodeid();
545 int from_local = 0;
546 int from_other = 0;
547 int from_dir = 0;
548 int create = 0;
549 int error;
550
551 if (flags & R_RECEIVE_REQUEST) {
552 if (from_nodeid == dir_nodeid)
553 from_dir = 1;
554 else
555 from_other = 1;
556 } else if (flags & R_REQUEST) {
557 from_local = 1;
558 }
559
560 /*
561 * flags & R_RECEIVE_RECOVER is from dlm_recover_master_copy, so
562 * from_nodeid has sent us a lock in dlm_recover_locks, believing
563 * we're the new master. Our local recovery may not have set
564 * res_master_nodeid to our_nodeid yet, so allow either. Don't
565 * create the rsb; dlm_recover_process_copy() will handle EBADR
566 * by resending.
567 *
568 * If someone sends us a request, we are the dir node, and we do
569 * not find the rsb anywhere, then recreate it. This happens if
570 * someone sends us a request after we have removed/freed an rsb
571 * from our toss list. (They sent a request instead of lookup
572 * because they are using an rsb from their toss list.)
573 */
574
575 if (from_local || from_dir ||
576 (from_other && (dir_nodeid == our_nodeid))) {
577 create = 1;
578 }
579
580 retry:
581 if (create) {
582 error = pre_rsb_struct(ls);
583 if (error < 0)
584 goto out;
585 }
586
587 spin_lock(&ls->ls_rsbtbl[b].lock);
588
589 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
590 if (error)
591 goto do_toss;
592
593 /*
594 * rsb is active, so we can't check master_nodeid without lock_rsb.
595 */
596
597 kref_get(&r->res_ref);
598 goto out_unlock;
599
600
601 do_toss:
602 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
603 if (error)
604 goto do_new;
605
606 /*
607 * rsb found inactive (master_nodeid may be out of date unless
608 * we are the dir_nodeid or were the master) No other thread
609 * is using this rsb because it's on the toss list, so we can
610 * look at or update res_master_nodeid without lock_rsb.
611 */
612
613 if ((r->res_master_nodeid != our_nodeid) && from_other) {
614 /* our rsb was not master, and another node (not the dir node)
615 has sent us a request */
616 log_debug(ls, "find_rsb toss from_other %d master %d dir %d %s",
617 from_nodeid, r->res_master_nodeid, dir_nodeid,
618 r->res_name);
619 error = -ENOTBLK;
620 goto out_unlock;
621 }
622
623 if ((r->res_master_nodeid != our_nodeid) && from_dir) {
624 /* don't think this should ever happen */
625 log_error(ls, "find_rsb toss from_dir %d master %d",
626 from_nodeid, r->res_master_nodeid);
627 dlm_print_rsb(r);
628 /* fix it and go on */
629 r->res_master_nodeid = our_nodeid;
630 r->res_nodeid = 0;
631 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
632 r->res_first_lkid = 0;
633 }
634
635 if (from_local && (r->res_master_nodeid != our_nodeid)) {
636 /* Because we have held no locks on this rsb,
637 res_master_nodeid could have become stale. */
638 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
639 r->res_first_lkid = 0;
640 }
641
642 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
643 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
644 goto out_unlock;
645
646
647 do_new:
648 /*
649 * rsb not found
650 */
651
652 if (error == -EBADR && !create)
653 goto out_unlock;
654
655 error = get_rsb_struct(ls, name, len, &r);
656 if (error == -EAGAIN) {
657 spin_unlock(&ls->ls_rsbtbl[b].lock);
658 goto retry;
659 }
660 if (error)
661 goto out_unlock;
662
663 r->res_hash = hash;
664 r->res_bucket = b;
665 r->res_dir_nodeid = dir_nodeid;
666 kref_init(&r->res_ref);
667
668 if (from_dir) {
669 /* want to see how often this happens */
670 log_debug(ls, "find_rsb new from_dir %d recreate %s",
671 from_nodeid, r->res_name);
672 r->res_master_nodeid = our_nodeid;
673 r->res_nodeid = 0;
674 goto out_add;
675 }
676
677 if (from_other && (dir_nodeid != our_nodeid)) {
678 /* should never happen */
679 log_error(ls, "find_rsb new from_other %d dir %d our %d %s",
680 from_nodeid, dir_nodeid, our_nodeid, r->res_name);
681 dlm_free_rsb(r);
682 r = NULL;
683 error = -ENOTBLK;
684 goto out_unlock;
685 }
686
687 if (from_other) {
688 log_debug(ls, "find_rsb new from_other %d dir %d %s",
689 from_nodeid, dir_nodeid, r->res_name);
690 }
691
692 if (dir_nodeid == our_nodeid) {
693 /* When we are the dir nodeid, we can set the master
694 node immediately */
695 r->res_master_nodeid = our_nodeid;
696 r->res_nodeid = 0;
697 } else {
698 /* set_master will send_lookup to dir_nodeid */
699 r->res_master_nodeid = 0;
700 r->res_nodeid = -1;
701 }
702
703 out_add:
704 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
705 out_unlock:
706 spin_unlock(&ls->ls_rsbtbl[b].lock);
707 out:
708 *r_ret = r;
709 return error;
710}
711
712/* During recovery, other nodes can send us new MSTCPY locks (from
713 dlm_recover_locks) before we've made ourself master (in
714 dlm_recover_masters). */
715
716static int find_rsb_nodir(struct dlm_ls *ls, const void *name, int len,
717 uint32_t hash, uint32_t b,
718 int dir_nodeid, int from_nodeid,
719 unsigned int flags, struct dlm_rsb **r_ret)
720{
721 struct dlm_rsb *r = NULL;
722 int our_nodeid = dlm_our_nodeid();
723 int recover = (flags & R_RECEIVE_RECOVER);
724 int error;
725
726 retry:
727 error = pre_rsb_struct(ls);
728 if (error < 0)
729 goto out;
730
731 spin_lock(&ls->ls_rsbtbl[b].lock);
732
733 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
734 if (error)
735 goto do_toss;
736
737 /*
738 * rsb is active, so we can't check master_nodeid without lock_rsb.
739 */
740
741 kref_get(&r->res_ref);
742 goto out_unlock;
743
744
745 do_toss:
746 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
747 if (error)
748 goto do_new;
749
750 /*
751 * rsb found inactive. No other thread is using this rsb because
752 * it's on the toss list, so we can look at or update
753 * res_master_nodeid without lock_rsb.
754 */
755
756 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
757 /* our rsb is not master, and another node has sent us a
758 request; this should never happen */
759 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
760 from_nodeid, r->res_master_nodeid, dir_nodeid);
761 dlm_print_rsb(r);
762 error = -ENOTBLK;
763 goto out_unlock;
764 }
765
766 if (!recover && (r->res_master_nodeid != our_nodeid) &&
767 (dir_nodeid == our_nodeid)) {
768 /* our rsb is not master, and we are dir; may as well fix it;
769 this should never happen */
770 log_error(ls, "find_rsb toss our %d master %d dir %d",
771 our_nodeid, r->res_master_nodeid, dir_nodeid);
772 dlm_print_rsb(r);
773 r->res_master_nodeid = our_nodeid;
774 r->res_nodeid = 0;
775 }
776
777 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
778 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
779 goto out_unlock;
780
781
782 do_new:
783 /*
784 * rsb not found
785 */
786
787 error = get_rsb_struct(ls, name, len, &r);
788 if (error == -EAGAIN) {
789 spin_unlock(&ls->ls_rsbtbl[b].lock);
790 goto retry;
791 }
792 if (error)
793 goto out_unlock;
794
795 r->res_hash = hash;
796 r->res_bucket = b;
797 r->res_dir_nodeid = dir_nodeid;
798 r->res_master_nodeid = dir_nodeid;
799 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
800 kref_init(&r->res_ref);
801
802 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
803 out_unlock:
804 spin_unlock(&ls->ls_rsbtbl[b].lock);
805 out:
806 *r_ret = r;
807 return error;
808}
809
810static int find_rsb(struct dlm_ls *ls, const void *name, int len,
811 int from_nodeid, unsigned int flags,
812 struct dlm_rsb **r_ret)
813{
814 uint32_t hash, b;
815 int dir_nodeid;
816
817 if (len > DLM_RESNAME_MAXLEN)
818 return -EINVAL;
819
820 hash = jhash(name, len, 0);
821 b = hash & (ls->ls_rsbtbl_size - 1);
822
823 dir_nodeid = dlm_hash2nodeid(ls, hash);
824
825 if (dlm_no_directory(ls))
826 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
827 from_nodeid, flags, r_ret);
828 else
829 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
830 from_nodeid, flags, r_ret);
831}
832
833/* we have received a request and found that res_master_nodeid != our_nodeid,
834 so we need to return an error or make ourself the master */
835
836static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
837 int from_nodeid)
838{
839 if (dlm_no_directory(ls)) {
840 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
841 from_nodeid, r->res_master_nodeid,
842 r->res_dir_nodeid);
843 dlm_print_rsb(r);
844 return -ENOTBLK;
845 }
846
847 if (from_nodeid != r->res_dir_nodeid) {
848 /* our rsb is not master, and another node (not the dir node)
849 has sent us a request. this is much more common when our
850 master_nodeid is zero, so limit debug to non-zero. */
851
852 if (r->res_master_nodeid) {
853 log_debug(ls, "validate master from_other %d master %d "
854 "dir %d first %x %s", from_nodeid,
855 r->res_master_nodeid, r->res_dir_nodeid,
856 r->res_first_lkid, r->res_name);
857 }
858 return -ENOTBLK;
859 } else {
860 /* our rsb is not master, but the dir nodeid has sent us a
861 request; this could happen with master 0 / res_nodeid -1 */
862
863 if (r->res_master_nodeid) {
864 log_error(ls, "validate master from_dir %d master %d "
865 "first %x %s",
866 from_nodeid, r->res_master_nodeid,
867 r->res_first_lkid, r->res_name);
868 }
869
870 r->res_master_nodeid = dlm_our_nodeid();
871 r->res_nodeid = 0;
872 return 0;
873 }
874}
875
876static void __dlm_master_lookup(struct dlm_ls *ls, struct dlm_rsb *r, int our_nodeid,
877 int from_nodeid, bool toss_list, unsigned int flags,
878 int *r_nodeid, int *result)
879{
880 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
881 int from_master = (flags & DLM_LU_RECOVER_DIR);
882
883 if (r->res_dir_nodeid != our_nodeid) {
884 /* should not happen, but may as well fix it and carry on */
885 log_error(ls, "%s res_dir %d our %d %s", __func__,
886 r->res_dir_nodeid, our_nodeid, r->res_name);
887 r->res_dir_nodeid = our_nodeid;
888 }
889
890 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
891 /* Recovery uses this function to set a new master when
892 * the previous master failed. Setting NEW_MASTER will
893 * force dlm_recover_masters to call recover_master on this
894 * rsb even though the res_nodeid is no longer removed.
895 */
896
897 r->res_master_nodeid = from_nodeid;
898 r->res_nodeid = from_nodeid;
899 rsb_set_flag(r, RSB_NEW_MASTER);
900
901 if (toss_list) {
902 /* I don't think we should ever find it on toss list. */
903 log_error(ls, "%s fix_master on toss", __func__);
904 dlm_dump_rsb(r);
905 }
906 }
907
908 if (from_master && (r->res_master_nodeid != from_nodeid)) {
909 /* this will happen if from_nodeid became master during
910 * a previous recovery cycle, and we aborted the previous
911 * cycle before recovering this master value
912 */
913
914 log_limit(ls, "%s from_master %d master_nodeid %d res_nodeid %d first %x %s",
915 __func__, from_nodeid, r->res_master_nodeid,
916 r->res_nodeid, r->res_first_lkid, r->res_name);
917
918 if (r->res_master_nodeid == our_nodeid) {
919 log_error(ls, "from_master %d our_master", from_nodeid);
920 dlm_dump_rsb(r);
921 goto ret_assign;
922 }
923
924 r->res_master_nodeid = from_nodeid;
925 r->res_nodeid = from_nodeid;
926 rsb_set_flag(r, RSB_NEW_MASTER);
927 }
928
929 if (!r->res_master_nodeid) {
930 /* this will happen if recovery happens while we're looking
931 * up the master for this rsb
932 */
933
934 log_debug(ls, "%s master 0 to %d first %x %s", __func__,
935 from_nodeid, r->res_first_lkid, r->res_name);
936 r->res_master_nodeid = from_nodeid;
937 r->res_nodeid = from_nodeid;
938 }
939
940 if (!from_master && !fix_master &&
941 (r->res_master_nodeid == from_nodeid)) {
942 /* this can happen when the master sends remove, the dir node
943 * finds the rsb on the keep list and ignores the remove,
944 * and the former master sends a lookup
945 */
946
947 log_limit(ls, "%s from master %d flags %x first %x %s",
948 __func__, from_nodeid, flags, r->res_first_lkid,
949 r->res_name);
950 }
951
952 ret_assign:
953 *r_nodeid = r->res_master_nodeid;
954 if (result)
955 *result = DLM_LU_MATCH;
956}
957
958/*
959 * We're the dir node for this res and another node wants to know the
960 * master nodeid. During normal operation (non recovery) this is only
961 * called from receive_lookup(); master lookups when the local node is
962 * the dir node are done by find_rsb().
963 *
964 * normal operation, we are the dir node for a resource
965 * . _request_lock
966 * . set_master
967 * . send_lookup
968 * . receive_lookup
969 * . dlm_master_lookup flags 0
970 *
971 * recover directory, we are rebuilding dir for all resources
972 * . dlm_recover_directory
973 * . dlm_rcom_names
974 * remote node sends back the rsb names it is master of and we are dir of
975 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
976 * we either create new rsb setting remote node as master, or find existing
977 * rsb and set master to be the remote node.
978 *
979 * recover masters, we are finding the new master for resources
980 * . dlm_recover_masters
981 * . recover_master
982 * . dlm_send_rcom_lookup
983 * . receive_rcom_lookup
984 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
985 */
986
987int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, const char *name,
988 int len, unsigned int flags, int *r_nodeid, int *result)
989{
990 struct dlm_rsb *r = NULL;
991 uint32_t hash, b;
992 int our_nodeid = dlm_our_nodeid();
993 int dir_nodeid, error;
994
995 if (len > DLM_RESNAME_MAXLEN)
996 return -EINVAL;
997
998 if (from_nodeid == our_nodeid) {
999 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
1000 our_nodeid, flags);
1001 return -EINVAL;
1002 }
1003
1004 hash = jhash(name, len, 0);
1005 b = hash & (ls->ls_rsbtbl_size - 1);
1006
1007 dir_nodeid = dlm_hash2nodeid(ls, hash);
1008 if (dir_nodeid != our_nodeid) {
1009 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
1010 from_nodeid, dir_nodeid, our_nodeid, hash,
1011 ls->ls_num_nodes);
1012 *r_nodeid = -1;
1013 return -EINVAL;
1014 }
1015
1016 retry:
1017 error = pre_rsb_struct(ls);
1018 if (error < 0)
1019 return error;
1020
1021 spin_lock(&ls->ls_rsbtbl[b].lock);
1022 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1023 if (!error) {
1024 /* because the rsb is active, we need to lock_rsb before
1025 * checking/changing re_master_nodeid
1026 */
1027
1028 hold_rsb(r);
1029 spin_unlock(&ls->ls_rsbtbl[b].lock);
1030 lock_rsb(r);
1031
1032 __dlm_master_lookup(ls, r, our_nodeid, from_nodeid, false,
1033 flags, r_nodeid, result);
1034
1035 /* the rsb was active */
1036 unlock_rsb(r);
1037 put_rsb(r);
1038
1039 return 0;
1040 }
1041
1042 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1043 if (error)
1044 goto not_found;
1045
1046 /* because the rsb is inactive (on toss list), it's not refcounted
1047 * and lock_rsb is not used, but is protected by the rsbtbl lock
1048 */
1049
1050 __dlm_master_lookup(ls, r, our_nodeid, from_nodeid, true, flags,
1051 r_nodeid, result);
1052
1053 r->res_toss_time = jiffies;
1054 /* the rsb was inactive (on toss list) */
1055 spin_unlock(&ls->ls_rsbtbl[b].lock);
1056
1057 return 0;
1058
1059 not_found:
1060 error = get_rsb_struct(ls, name, len, &r);
1061 if (error == -EAGAIN) {
1062 spin_unlock(&ls->ls_rsbtbl[b].lock);
1063 goto retry;
1064 }
1065 if (error)
1066 goto out_unlock;
1067
1068 r->res_hash = hash;
1069 r->res_bucket = b;
1070 r->res_dir_nodeid = our_nodeid;
1071 r->res_master_nodeid = from_nodeid;
1072 r->res_nodeid = from_nodeid;
1073 kref_init(&r->res_ref);
1074 r->res_toss_time = jiffies;
1075
1076 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1077 if (error) {
1078 /* should never happen */
1079 dlm_free_rsb(r);
1080 spin_unlock(&ls->ls_rsbtbl[b].lock);
1081 goto retry;
1082 }
1083
1084 if (result)
1085 *result = DLM_LU_ADD;
1086 *r_nodeid = from_nodeid;
1087 out_unlock:
1088 spin_unlock(&ls->ls_rsbtbl[b].lock);
1089 return error;
1090}
1091
1092static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1093{
1094 struct rb_node *n;
1095 struct dlm_rsb *r;
1096 int i;
1097
1098 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1099 spin_lock(&ls->ls_rsbtbl[i].lock);
1100 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1101 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1102 if (r->res_hash == hash)
1103 dlm_dump_rsb(r);
1104 }
1105 spin_unlock(&ls->ls_rsbtbl[i].lock);
1106 }
1107}
1108
1109void dlm_dump_rsb_name(struct dlm_ls *ls, const char *name, int len)
1110{
1111 struct dlm_rsb *r = NULL;
1112 uint32_t hash, b;
1113 int error;
1114
1115 hash = jhash(name, len, 0);
1116 b = hash & (ls->ls_rsbtbl_size - 1);
1117
1118 spin_lock(&ls->ls_rsbtbl[b].lock);
1119 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1120 if (!error)
1121 goto out_dump;
1122
1123 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1124 if (error)
1125 goto out;
1126 out_dump:
1127 dlm_dump_rsb(r);
1128 out:
1129 spin_unlock(&ls->ls_rsbtbl[b].lock);
1130}
1131
1132static void toss_rsb(struct kref *kref)
1133{
1134 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1135 struct dlm_ls *ls = r->res_ls;
1136
1137 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1138 kref_init(&r->res_ref);
1139 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1140 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
1141 r->res_toss_time = jiffies;
1142 set_bit(DLM_RTF_SHRINK_BIT, &ls->ls_rsbtbl[r->res_bucket].flags);
1143 if (r->res_lvbptr) {
1144 dlm_free_lvb(r->res_lvbptr);
1145 r->res_lvbptr = NULL;
1146 }
1147}
1148
1149/* See comment for unhold_lkb */
1150
1151static void unhold_rsb(struct dlm_rsb *r)
1152{
1153 int rv;
1154 rv = kref_put(&r->res_ref, toss_rsb);
1155 DLM_ASSERT(!rv, dlm_dump_rsb(r););
1156}
1157
1158static void kill_rsb(struct kref *kref)
1159{
1160 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1161
1162 /* All work is done after the return from kref_put() so we
1163 can release the write_lock before the remove and free. */
1164
1165 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1166 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1167 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1168 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1169 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1170 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
1171}
1172
1173/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1174 The rsb must exist as long as any lkb's for it do. */
1175
1176static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1177{
1178 hold_rsb(r);
1179 lkb->lkb_resource = r;
1180}
1181
1182static void detach_lkb(struct dlm_lkb *lkb)
1183{
1184 if (lkb->lkb_resource) {
1185 put_rsb(lkb->lkb_resource);
1186 lkb->lkb_resource = NULL;
1187 }
1188}
1189
1190static int _create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret,
1191 int start, int end)
1192{
1193 struct dlm_lkb *lkb;
1194 int rv;
1195
1196 lkb = dlm_allocate_lkb(ls);
1197 if (!lkb)
1198 return -ENOMEM;
1199
1200 lkb->lkb_last_bast_mode = -1;
1201 lkb->lkb_nodeid = -1;
1202 lkb->lkb_grmode = DLM_LOCK_IV;
1203 kref_init(&lkb->lkb_ref);
1204 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
1205 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
1206 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1207 INIT_LIST_HEAD(&lkb->lkb_callbacks);
1208 spin_lock_init(&lkb->lkb_cb_lock);
1209 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
1210
1211 idr_preload(GFP_NOFS);
1212 spin_lock(&ls->ls_lkbidr_spin);
1213 rv = idr_alloc(&ls->ls_lkbidr, lkb, start, end, GFP_NOWAIT);
1214 if (rv >= 0)
1215 lkb->lkb_id = rv;
1216 spin_unlock(&ls->ls_lkbidr_spin);
1217 idr_preload_end();
1218
1219 if (rv < 0) {
1220 log_error(ls, "create_lkb idr error %d", rv);
1221 dlm_free_lkb(lkb);
1222 return rv;
1223 }
1224
1225 *lkb_ret = lkb;
1226 return 0;
1227}
1228
1229static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1230{
1231 return _create_lkb(ls, lkb_ret, 1, 0);
1232}
1233
1234static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1235{
1236 struct dlm_lkb *lkb;
1237
1238 spin_lock(&ls->ls_lkbidr_spin);
1239 lkb = idr_find(&ls->ls_lkbidr, lkid);
1240 if (lkb)
1241 kref_get(&lkb->lkb_ref);
1242 spin_unlock(&ls->ls_lkbidr_spin);
1243
1244 *lkb_ret = lkb;
1245 return lkb ? 0 : -ENOENT;
1246}
1247
1248static void kill_lkb(struct kref *kref)
1249{
1250 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1251
1252 /* All work is done after the return from kref_put() so we
1253 can release the write_lock before the detach_lkb */
1254
1255 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1256}
1257
1258/* __put_lkb() is used when an lkb may not have an rsb attached to
1259 it so we need to provide the lockspace explicitly */
1260
1261static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
1262{
1263 uint32_t lkid = lkb->lkb_id;
1264 int rv;
1265
1266 rv = kref_put_lock(&lkb->lkb_ref, kill_lkb,
1267 &ls->ls_lkbidr_spin);
1268 if (rv) {
1269 idr_remove(&ls->ls_lkbidr, lkid);
1270 spin_unlock(&ls->ls_lkbidr_spin);
1271
1272 detach_lkb(lkb);
1273
1274 /* for local/process lkbs, lvbptr points to caller's lksb */
1275 if (lkb->lkb_lvbptr && is_master_copy(lkb))
1276 dlm_free_lvb(lkb->lkb_lvbptr);
1277 dlm_free_lkb(lkb);
1278 }
1279
1280 return rv;
1281}
1282
1283int dlm_put_lkb(struct dlm_lkb *lkb)
1284{
1285 struct dlm_ls *ls;
1286
1287 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1288 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1289
1290 ls = lkb->lkb_resource->res_ls;
1291 return __put_lkb(ls, lkb);
1292}
1293
1294/* This is only called to add a reference when the code already holds
1295 a valid reference to the lkb, so there's no need for locking. */
1296
1297static inline void hold_lkb(struct dlm_lkb *lkb)
1298{
1299 kref_get(&lkb->lkb_ref);
1300}
1301
1302static void unhold_lkb_assert(struct kref *kref)
1303{
1304 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1305
1306 DLM_ASSERT(false, dlm_print_lkb(lkb););
1307}
1308
1309/* This is called when we need to remove a reference and are certain
1310 it's not the last ref. e.g. del_lkb is always called between a
1311 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1312 put_lkb would work fine, but would involve unnecessary locking */
1313
1314static inline void unhold_lkb(struct dlm_lkb *lkb)
1315{
1316 kref_put(&lkb->lkb_ref, unhold_lkb_assert);
1317}
1318
1319static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1320 int mode)
1321{
1322 struct dlm_lkb *lkb = NULL, *iter;
1323
1324 list_for_each_entry(iter, head, lkb_statequeue)
1325 if (iter->lkb_rqmode < mode) {
1326 lkb = iter;
1327 list_add_tail(new, &iter->lkb_statequeue);
1328 break;
1329 }
1330
1331 if (!lkb)
1332 list_add_tail(new, head);
1333}
1334
1335/* add/remove lkb to rsb's grant/convert/wait queue */
1336
1337static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1338{
1339 kref_get(&lkb->lkb_ref);
1340
1341 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1342
1343 lkb->lkb_timestamp = ktime_get();
1344
1345 lkb->lkb_status = status;
1346
1347 switch (status) {
1348 case DLM_LKSTS_WAITING:
1349 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1350 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1351 else
1352 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1353 break;
1354 case DLM_LKSTS_GRANTED:
1355 /* convention says granted locks kept in order of grmode */
1356 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1357 lkb->lkb_grmode);
1358 break;
1359 case DLM_LKSTS_CONVERT:
1360 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1361 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1362 else
1363 list_add_tail(&lkb->lkb_statequeue,
1364 &r->res_convertqueue);
1365 break;
1366 default:
1367 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1368 }
1369}
1370
1371static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1372{
1373 lkb->lkb_status = 0;
1374 list_del(&lkb->lkb_statequeue);
1375 unhold_lkb(lkb);
1376}
1377
1378static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1379{
1380 hold_lkb(lkb);
1381 del_lkb(r, lkb);
1382 add_lkb(r, lkb, sts);
1383 unhold_lkb(lkb);
1384}
1385
1386static int msg_reply_type(int mstype)
1387{
1388 switch (mstype) {
1389 case DLM_MSG_REQUEST:
1390 return DLM_MSG_REQUEST_REPLY;
1391 case DLM_MSG_CONVERT:
1392 return DLM_MSG_CONVERT_REPLY;
1393 case DLM_MSG_UNLOCK:
1394 return DLM_MSG_UNLOCK_REPLY;
1395 case DLM_MSG_CANCEL:
1396 return DLM_MSG_CANCEL_REPLY;
1397 case DLM_MSG_LOOKUP:
1398 return DLM_MSG_LOOKUP_REPLY;
1399 }
1400 return -1;
1401}
1402
1403/* add/remove lkb from global waiters list of lkb's waiting for
1404 a reply from a remote node */
1405
1406static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
1407{
1408 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1409 int error = 0;
1410 int wc;
1411
1412 mutex_lock(&ls->ls_waiters_mutex);
1413
1414 if (is_overlap_unlock(lkb) ||
1415 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1416 error = -EINVAL;
1417 goto out;
1418 }
1419
1420 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1421 switch (mstype) {
1422 case DLM_MSG_UNLOCK:
1423 set_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
1424 break;
1425 case DLM_MSG_CANCEL:
1426 set_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
1427 break;
1428 default:
1429 error = -EBUSY;
1430 goto out;
1431 }
1432 wc = atomic_inc_return(&lkb->lkb_wait_count);
1433 hold_lkb(lkb);
1434
1435 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
1436 lkb->lkb_id, lkb->lkb_wait_type, mstype, wc,
1437 dlm_iflags_val(lkb));
1438 goto out;
1439 }
1440
1441 wc = atomic_fetch_inc(&lkb->lkb_wait_count);
1442 DLM_ASSERT(!wc, dlm_print_lkb(lkb); printk("wait_count %d\n", wc););
1443 lkb->lkb_wait_type = mstype;
1444 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
1445 hold_lkb(lkb);
1446 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1447 out:
1448 if (error)
1449 log_error(ls, "addwait error %x %d flags %x %d %d %s",
1450 lkb->lkb_id, error, dlm_iflags_val(lkb), mstype,
1451 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
1452 mutex_unlock(&ls->ls_waiters_mutex);
1453 return error;
1454}
1455
1456/* We clear the RESEND flag because we might be taking an lkb off the waiters
1457 list as part of process_requestqueue (e.g. a lookup that has an optimized
1458 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1459 set RESEND and dlm_recover_waiters_post() */
1460
1461static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1462 const struct dlm_message *ms)
1463{
1464 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1465 int overlap_done = 0;
1466
1467 if (mstype == DLM_MSG_UNLOCK_REPLY &&
1468 test_and_clear_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags)) {
1469 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
1470 overlap_done = 1;
1471 goto out_del;
1472 }
1473
1474 if (mstype == DLM_MSG_CANCEL_REPLY &&
1475 test_and_clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags)) {
1476 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
1477 overlap_done = 1;
1478 goto out_del;
1479 }
1480
1481 /* Cancel state was preemptively cleared by a successful convert,
1482 see next comment, nothing to do. */
1483
1484 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1485 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1486 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1487 lkb->lkb_id, lkb->lkb_wait_type);
1488 return -1;
1489 }
1490
1491 /* Remove for the convert reply, and premptively remove for the
1492 cancel reply. A convert has been granted while there's still
1493 an outstanding cancel on it (the cancel is moot and the result
1494 in the cancel reply should be 0). We preempt the cancel reply
1495 because the app gets the convert result and then can follow up
1496 with another op, like convert. This subsequent op would see the
1497 lingering state of the cancel and fail with -EBUSY. */
1498
1499 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1500 (lkb->lkb_wait_type == DLM_MSG_CONVERT) && ms && !ms->m_result &&
1501 test_and_clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags)) {
1502 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1503 lkb->lkb_id);
1504 lkb->lkb_wait_type = 0;
1505 atomic_dec(&lkb->lkb_wait_count);
1506 unhold_lkb(lkb);
1507 goto out_del;
1508 }
1509
1510 /* N.B. type of reply may not always correspond to type of original
1511 msg due to lookup->request optimization, verify others? */
1512
1513 if (lkb->lkb_wait_type) {
1514 lkb->lkb_wait_type = 0;
1515 goto out_del;
1516 }
1517
1518 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1519 lkb->lkb_id, ms ? le32_to_cpu(ms->m_header.h_nodeid) : 0,
1520 lkb->lkb_remid, mstype, dlm_iflags_val(lkb));
1521 return -1;
1522
1523 out_del:
1524 /* the force-unlock/cancel has completed and we haven't recvd a reply
1525 to the op that was in progress prior to the unlock/cancel; we
1526 give up on any reply to the earlier op. FIXME: not sure when/how
1527 this would happen */
1528
1529 if (overlap_done && lkb->lkb_wait_type) {
1530 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
1531 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1532 atomic_dec(&lkb->lkb_wait_count);
1533 unhold_lkb(lkb);
1534 lkb->lkb_wait_type = 0;
1535 }
1536
1537 DLM_ASSERT(atomic_read(&lkb->lkb_wait_count), dlm_print_lkb(lkb););
1538
1539 clear_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags);
1540 if (atomic_dec_and_test(&lkb->lkb_wait_count))
1541 list_del_init(&lkb->lkb_wait_reply);
1542 unhold_lkb(lkb);
1543 return 0;
1544}
1545
1546static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
1547{
1548 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1549 int error;
1550
1551 mutex_lock(&ls->ls_waiters_mutex);
1552 error = _remove_from_waiters(lkb, mstype, NULL);
1553 mutex_unlock(&ls->ls_waiters_mutex);
1554 return error;
1555}
1556
1557/* Handles situations where we might be processing a "fake" or "local" reply in
1558 which we can't try to take waiters_mutex again. */
1559
1560static int remove_from_waiters_ms(struct dlm_lkb *lkb,
1561 const struct dlm_message *ms, bool local)
1562{
1563 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1564 int error;
1565
1566 if (!local)
1567 mutex_lock(&ls->ls_waiters_mutex);
1568 error = _remove_from_waiters(lkb, le32_to_cpu(ms->m_type), ms);
1569 if (!local)
1570 mutex_unlock(&ls->ls_waiters_mutex);
1571 return error;
1572}
1573
1574static void shrink_bucket(struct dlm_ls *ls, int b)
1575{
1576 struct rb_node *n, *next;
1577 struct dlm_rsb *r;
1578 char *name;
1579 int our_nodeid = dlm_our_nodeid();
1580 int remote_count = 0;
1581 int need_shrink = 0;
1582 int i, len, rv;
1583
1584 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
1585
1586 spin_lock(&ls->ls_rsbtbl[b].lock);
1587
1588 if (!test_bit(DLM_RTF_SHRINK_BIT, &ls->ls_rsbtbl[b].flags)) {
1589 spin_unlock(&ls->ls_rsbtbl[b].lock);
1590 return;
1591 }
1592
1593 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) {
1594 next = rb_next(n);
1595 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1596
1597 /* If we're the directory record for this rsb, and
1598 we're not the master of it, then we need to wait
1599 for the master node to send us a dir remove for
1600 before removing the dir record. */
1601
1602 if (!dlm_no_directory(ls) &&
1603 (r->res_master_nodeid != our_nodeid) &&
1604 (dlm_dir_nodeid(r) == our_nodeid)) {
1605 continue;
1606 }
1607
1608 need_shrink = 1;
1609
1610 if (!time_after_eq(jiffies, r->res_toss_time +
1611 dlm_config.ci_toss_secs * HZ)) {
1612 continue;
1613 }
1614
1615 if (!dlm_no_directory(ls) &&
1616 (r->res_master_nodeid == our_nodeid) &&
1617 (dlm_dir_nodeid(r) != our_nodeid)) {
1618
1619 /* We're the master of this rsb but we're not
1620 the directory record, so we need to tell the
1621 dir node to remove the dir record. */
1622
1623 ls->ls_remove_lens[remote_count] = r->res_length;
1624 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1625 DLM_RESNAME_MAXLEN);
1626 remote_count++;
1627
1628 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1629 break;
1630 continue;
1631 }
1632
1633 if (!kref_put(&r->res_ref, kill_rsb)) {
1634 log_error(ls, "tossed rsb in use %s", r->res_name);
1635 continue;
1636 }
1637
1638 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1639 dlm_free_rsb(r);
1640 }
1641
1642 if (need_shrink)
1643 set_bit(DLM_RTF_SHRINK_BIT, &ls->ls_rsbtbl[b].flags);
1644 else
1645 clear_bit(DLM_RTF_SHRINK_BIT, &ls->ls_rsbtbl[b].flags);
1646 spin_unlock(&ls->ls_rsbtbl[b].lock);
1647
1648 /*
1649 * While searching for rsb's to free, we found some that require
1650 * remote removal. We leave them in place and find them again here
1651 * so there is a very small gap between removing them from the toss
1652 * list and sending the removal. Keeping this gap small is
1653 * important to keep us (the master node) from being out of sync
1654 * with the remote dir node for very long.
1655 */
1656
1657 for (i = 0; i < remote_count; i++) {
1658 name = ls->ls_remove_names[i];
1659 len = ls->ls_remove_lens[i];
1660
1661 spin_lock(&ls->ls_rsbtbl[b].lock);
1662 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1663 if (rv) {
1664 spin_unlock(&ls->ls_rsbtbl[b].lock);
1665 log_debug(ls, "remove_name not toss %s", name);
1666 continue;
1667 }
1668
1669 if (r->res_master_nodeid != our_nodeid) {
1670 spin_unlock(&ls->ls_rsbtbl[b].lock);
1671 log_debug(ls, "remove_name master %d dir %d our %d %s",
1672 r->res_master_nodeid, r->res_dir_nodeid,
1673 our_nodeid, name);
1674 continue;
1675 }
1676
1677 if (r->res_dir_nodeid == our_nodeid) {
1678 /* should never happen */
1679 spin_unlock(&ls->ls_rsbtbl[b].lock);
1680 log_error(ls, "remove_name dir %d master %d our %d %s",
1681 r->res_dir_nodeid, r->res_master_nodeid,
1682 our_nodeid, name);
1683 continue;
1684 }
1685
1686 if (!time_after_eq(jiffies, r->res_toss_time +
1687 dlm_config.ci_toss_secs * HZ)) {
1688 spin_unlock(&ls->ls_rsbtbl[b].lock);
1689 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1690 r->res_toss_time, jiffies, name);
1691 continue;
1692 }
1693
1694 if (!kref_put(&r->res_ref, kill_rsb)) {
1695 spin_unlock(&ls->ls_rsbtbl[b].lock);
1696 log_error(ls, "remove_name in use %s", name);
1697 continue;
1698 }
1699
1700 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1701 send_remove(r);
1702 spin_unlock(&ls->ls_rsbtbl[b].lock);
1703
1704 dlm_free_rsb(r);
1705 }
1706}
1707
1708void dlm_scan_rsbs(struct dlm_ls *ls)
1709{
1710 int i;
1711
1712 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1713 shrink_bucket(ls, i);
1714 if (dlm_locking_stopped(ls))
1715 break;
1716 cond_resched();
1717 }
1718}
1719
1720/* lkb is master or local copy */
1721
1722static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1723{
1724 int b, len = r->res_ls->ls_lvblen;
1725
1726 /* b=1 lvb returned to caller
1727 b=0 lvb written to rsb or invalidated
1728 b=-1 do nothing */
1729
1730 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1731
1732 if (b == 1) {
1733 if (!lkb->lkb_lvbptr)
1734 return;
1735
1736 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1737 return;
1738
1739 if (!r->res_lvbptr)
1740 return;
1741
1742 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1743 lkb->lkb_lvbseq = r->res_lvbseq;
1744
1745 } else if (b == 0) {
1746 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1747 rsb_set_flag(r, RSB_VALNOTVALID);
1748 return;
1749 }
1750
1751 if (!lkb->lkb_lvbptr)
1752 return;
1753
1754 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1755 return;
1756
1757 if (!r->res_lvbptr)
1758 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1759
1760 if (!r->res_lvbptr)
1761 return;
1762
1763 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1764 r->res_lvbseq++;
1765 lkb->lkb_lvbseq = r->res_lvbseq;
1766 rsb_clear_flag(r, RSB_VALNOTVALID);
1767 }
1768
1769 if (rsb_flag(r, RSB_VALNOTVALID))
1770 set_bit(DLM_SBF_VALNOTVALID_BIT, &lkb->lkb_sbflags);
1771}
1772
1773static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1774{
1775 if (lkb->lkb_grmode < DLM_LOCK_PW)
1776 return;
1777
1778 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1779 rsb_set_flag(r, RSB_VALNOTVALID);
1780 return;
1781 }
1782
1783 if (!lkb->lkb_lvbptr)
1784 return;
1785
1786 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1787 return;
1788
1789 if (!r->res_lvbptr)
1790 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1791
1792 if (!r->res_lvbptr)
1793 return;
1794
1795 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
1796 r->res_lvbseq++;
1797 rsb_clear_flag(r, RSB_VALNOTVALID);
1798}
1799
1800/* lkb is process copy (pc) */
1801
1802static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1803 const struct dlm_message *ms)
1804{
1805 int b;
1806
1807 if (!lkb->lkb_lvbptr)
1808 return;
1809
1810 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1811 return;
1812
1813 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1814 if (b == 1) {
1815 int len = receive_extralen(ms);
1816 if (len > r->res_ls->ls_lvblen)
1817 len = r->res_ls->ls_lvblen;
1818 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
1819 lkb->lkb_lvbseq = le32_to_cpu(ms->m_lvbseq);
1820 }
1821}
1822
1823/* Manipulate lkb's on rsb's convert/granted/waiting queues
1824 remove_lock -- used for unlock, removes lkb from granted
1825 revert_lock -- used for cancel, moves lkb from convert to granted
1826 grant_lock -- used for request and convert, adds lkb to granted or
1827 moves lkb from convert or waiting to granted
1828
1829 Each of these is used for master or local copy lkb's. There is
1830 also a _pc() variation used to make the corresponding change on
1831 a process copy (pc) lkb. */
1832
1833static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1834{
1835 del_lkb(r, lkb);
1836 lkb->lkb_grmode = DLM_LOCK_IV;
1837 /* this unhold undoes the original ref from create_lkb()
1838 so this leads to the lkb being freed */
1839 unhold_lkb(lkb);
1840}
1841
1842static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1843{
1844 set_lvb_unlock(r, lkb);
1845 _remove_lock(r, lkb);
1846}
1847
1848static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1849{
1850 _remove_lock(r, lkb);
1851}
1852
1853/* returns: 0 did nothing
1854 1 moved lock to granted
1855 -1 removed lock */
1856
1857static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1858{
1859 int rv = 0;
1860
1861 lkb->lkb_rqmode = DLM_LOCK_IV;
1862
1863 switch (lkb->lkb_status) {
1864 case DLM_LKSTS_GRANTED:
1865 break;
1866 case DLM_LKSTS_CONVERT:
1867 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1868 rv = 1;
1869 break;
1870 case DLM_LKSTS_WAITING:
1871 del_lkb(r, lkb);
1872 lkb->lkb_grmode = DLM_LOCK_IV;
1873 /* this unhold undoes the original ref from create_lkb()
1874 so this leads to the lkb being freed */
1875 unhold_lkb(lkb);
1876 rv = -1;
1877 break;
1878 default:
1879 log_print("invalid status for revert %d", lkb->lkb_status);
1880 }
1881 return rv;
1882}
1883
1884static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1885{
1886 return revert_lock(r, lkb);
1887}
1888
1889static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1890{
1891 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
1892 lkb->lkb_grmode = lkb->lkb_rqmode;
1893 if (lkb->lkb_status)
1894 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1895 else
1896 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
1897 }
1898
1899 lkb->lkb_rqmode = DLM_LOCK_IV;
1900 lkb->lkb_highbast = 0;
1901}
1902
1903static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1904{
1905 set_lvb_lock(r, lkb);
1906 _grant_lock(r, lkb);
1907}
1908
1909static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1910 const struct dlm_message *ms)
1911{
1912 set_lvb_lock_pc(r, lkb, ms);
1913 _grant_lock(r, lkb);
1914}
1915
1916/* called by grant_pending_locks() which means an async grant message must
1917 be sent to the requesting node in addition to granting the lock if the
1918 lkb belongs to a remote node. */
1919
1920static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
1921{
1922 grant_lock(r, lkb);
1923 if (is_master_copy(lkb))
1924 send_grant(r, lkb);
1925 else
1926 queue_cast(r, lkb, 0);
1927}
1928
1929/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
1930 change the granted/requested modes. We're munging things accordingly in
1931 the process copy.
1932 CONVDEADLK: our grmode may have been forced down to NL to resolve a
1933 conversion deadlock
1934 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
1935 compatible with other granted locks */
1936
1937static void munge_demoted(struct dlm_lkb *lkb)
1938{
1939 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
1940 log_print("munge_demoted %x invalid modes gr %d rq %d",
1941 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
1942 return;
1943 }
1944
1945 lkb->lkb_grmode = DLM_LOCK_NL;
1946}
1947
1948static void munge_altmode(struct dlm_lkb *lkb, const struct dlm_message *ms)
1949{
1950 if (ms->m_type != cpu_to_le32(DLM_MSG_REQUEST_REPLY) &&
1951 ms->m_type != cpu_to_le32(DLM_MSG_GRANT)) {
1952 log_print("munge_altmode %x invalid reply type %d",
1953 lkb->lkb_id, le32_to_cpu(ms->m_type));
1954 return;
1955 }
1956
1957 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
1958 lkb->lkb_rqmode = DLM_LOCK_PR;
1959 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
1960 lkb->lkb_rqmode = DLM_LOCK_CW;
1961 else {
1962 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
1963 dlm_print_lkb(lkb);
1964 }
1965}
1966
1967static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
1968{
1969 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
1970 lkb_statequeue);
1971 if (lkb->lkb_id == first->lkb_id)
1972 return 1;
1973
1974 return 0;
1975}
1976
1977/* Check if the given lkb conflicts with another lkb on the queue. */
1978
1979static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
1980{
1981 struct dlm_lkb *this;
1982
1983 list_for_each_entry(this, head, lkb_statequeue) {
1984 if (this == lkb)
1985 continue;
1986 if (!modes_compat(this, lkb))
1987 return 1;
1988 }
1989 return 0;
1990}
1991
1992/*
1993 * "A conversion deadlock arises with a pair of lock requests in the converting
1994 * queue for one resource. The granted mode of each lock blocks the requested
1995 * mode of the other lock."
1996 *
1997 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
1998 * convert queue from being granted, then deadlk/demote lkb.
1999 *
2000 * Example:
2001 * Granted Queue: empty
2002 * Convert Queue: NL->EX (first lock)
2003 * PR->EX (second lock)
2004 *
2005 * The first lock can't be granted because of the granted mode of the second
2006 * lock and the second lock can't be granted because it's not first in the
2007 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2008 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2009 * flag set and return DEMOTED in the lksb flags.
2010 *
2011 * Originally, this function detected conv-deadlk in a more limited scope:
2012 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2013 * - if lkb1 was the first entry in the queue (not just earlier), and was
2014 * blocked by the granted mode of lkb2, and there was nothing on the
2015 * granted queue preventing lkb1 from being granted immediately, i.e.
2016 * lkb2 was the only thing preventing lkb1 from being granted.
2017 *
2018 * That second condition meant we'd only say there was conv-deadlk if
2019 * resolving it (by demotion) would lead to the first lock on the convert
2020 * queue being granted right away. It allowed conversion deadlocks to exist
2021 * between locks on the convert queue while they couldn't be granted anyway.
2022 *
2023 * Now, we detect and take action on conversion deadlocks immediately when
2024 * they're created, even if they may not be immediately consequential. If
2025 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2026 * mode that would prevent lkb1's conversion from being granted, we do a
2027 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2028 * I think this means that the lkb_is_ahead condition below should always
2029 * be zero, i.e. there will never be conv-deadlk between two locks that are
2030 * both already on the convert queue.
2031 */
2032
2033static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
2034{
2035 struct dlm_lkb *lkb1;
2036 int lkb_is_ahead = 0;
2037
2038 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2039 if (lkb1 == lkb2) {
2040 lkb_is_ahead = 1;
2041 continue;
2042 }
2043
2044 if (!lkb_is_ahead) {
2045 if (!modes_compat(lkb2, lkb1))
2046 return 1;
2047 } else {
2048 if (!modes_compat(lkb2, lkb1) &&
2049 !modes_compat(lkb1, lkb2))
2050 return 1;
2051 }
2052 }
2053 return 0;
2054}
2055
2056/*
2057 * Return 1 if the lock can be granted, 0 otherwise.
2058 * Also detect and resolve conversion deadlocks.
2059 *
2060 * lkb is the lock to be granted
2061 *
2062 * now is 1 if the function is being called in the context of the
2063 * immediate request, it is 0 if called later, after the lock has been
2064 * queued.
2065 *
2066 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2067 * after recovery.
2068 *
2069 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2070 */
2071
2072static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2073 int recover)
2074{
2075 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2076
2077 /*
2078 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2079 * a new request for a NL mode lock being blocked.
2080 *
2081 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2082 * request, then it would be granted. In essence, the use of this flag
2083 * tells the Lock Manager to expedite theis request by not considering
2084 * what may be in the CONVERTING or WAITING queues... As of this
2085 * writing, the EXPEDITE flag can be used only with new requests for NL
2086 * mode locks. This flag is not valid for conversion requests.
2087 *
2088 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2089 * conversion or used with a non-NL requested mode. We also know an
2090 * EXPEDITE request is always granted immediately, so now must always
2091 * be 1. The full condition to grant an expedite request: (now &&
2092 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2093 * therefore be shortened to just checking the flag.
2094 */
2095
2096 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
2097 return 1;
2098
2099 /*
2100 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2101 * added to the remaining conditions.
2102 */
2103
2104 if (queue_conflict(&r->res_grantqueue, lkb))
2105 return 0;
2106
2107 /*
2108 * 6-3: By default, a conversion request is immediately granted if the
2109 * requested mode is compatible with the modes of all other granted
2110 * locks
2111 */
2112
2113 if (queue_conflict(&r->res_convertqueue, lkb))
2114 return 0;
2115
2116 /*
2117 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2118 * locks for a recovered rsb, on which lkb's have been rebuilt.
2119 * The lkb's may have been rebuilt on the queues in a different
2120 * order than they were in on the previous master. So, granting
2121 * queued conversions in order after recovery doesn't make sense
2122 * since the order hasn't been preserved anyway. The new order
2123 * could also have created a new "in place" conversion deadlock.
2124 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2125 * After recovery, there would be no granted locks, and possibly
2126 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2127 * recovery, grant conversions without considering order.
2128 */
2129
2130 if (conv && recover)
2131 return 1;
2132
2133 /*
2134 * 6-5: But the default algorithm for deciding whether to grant or
2135 * queue conversion requests does not by itself guarantee that such
2136 * requests are serviced on a "first come first serve" basis. This, in
2137 * turn, can lead to a phenomenon known as "indefinate postponement".
2138 *
2139 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2140 * the system service employed to request a lock conversion. This flag
2141 * forces certain conversion requests to be queued, even if they are
2142 * compatible with the granted modes of other locks on the same
2143 * resource. Thus, the use of this flag results in conversion requests
2144 * being ordered on a "first come first servce" basis.
2145 *
2146 * DCT: This condition is all about new conversions being able to occur
2147 * "in place" while the lock remains on the granted queue (assuming
2148 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2149 * doesn't _have_ to go onto the convert queue where it's processed in
2150 * order. The "now" variable is necessary to distinguish converts
2151 * being received and processed for the first time now, because once a
2152 * convert is moved to the conversion queue the condition below applies
2153 * requiring fifo granting.
2154 */
2155
2156 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
2157 return 1;
2158
2159 /*
2160 * Even if the convert is compat with all granted locks,
2161 * QUECVT forces it behind other locks on the convert queue.
2162 */
2163
2164 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2165 if (list_empty(&r->res_convertqueue))
2166 return 1;
2167 else
2168 return 0;
2169 }
2170
2171 /*
2172 * The NOORDER flag is set to avoid the standard vms rules on grant
2173 * order.
2174 */
2175
2176 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
2177 return 1;
2178
2179 /*
2180 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2181 * granted until all other conversion requests ahead of it are granted
2182 * and/or canceled.
2183 */
2184
2185 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
2186 return 1;
2187
2188 /*
2189 * 6-4: By default, a new request is immediately granted only if all
2190 * three of the following conditions are satisfied when the request is
2191 * issued:
2192 * - The queue of ungranted conversion requests for the resource is
2193 * empty.
2194 * - The queue of ungranted new requests for the resource is empty.
2195 * - The mode of the new request is compatible with the most
2196 * restrictive mode of all granted locks on the resource.
2197 */
2198
2199 if (now && !conv && list_empty(&r->res_convertqueue) &&
2200 list_empty(&r->res_waitqueue))
2201 return 1;
2202
2203 /*
2204 * 6-4: Once a lock request is in the queue of ungranted new requests,
2205 * it cannot be granted until the queue of ungranted conversion
2206 * requests is empty, all ungranted new requests ahead of it are
2207 * granted and/or canceled, and it is compatible with the granted mode
2208 * of the most restrictive lock granted on the resource.
2209 */
2210
2211 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2212 first_in_list(lkb, &r->res_waitqueue))
2213 return 1;
2214
2215 return 0;
2216}
2217
2218static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2219 int recover, int *err)
2220{
2221 int rv;
2222 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
2223 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2224
2225 if (err)
2226 *err = 0;
2227
2228 rv = _can_be_granted(r, lkb, now, recover);
2229 if (rv)
2230 goto out;
2231
2232 /*
2233 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2234 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2235 * cancels one of the locks.
2236 */
2237
2238 if (is_convert && can_be_queued(lkb) &&
2239 conversion_deadlock_detect(r, lkb)) {
2240 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2241 lkb->lkb_grmode = DLM_LOCK_NL;
2242 set_bit(DLM_SBF_DEMOTED_BIT, &lkb->lkb_sbflags);
2243 } else if (err) {
2244 *err = -EDEADLK;
2245 } else {
2246 log_print("can_be_granted deadlock %x now %d",
2247 lkb->lkb_id, now);
2248 dlm_dump_rsb(r);
2249 }
2250 goto out;
2251 }
2252
2253 /*
2254 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2255 * to grant a request in a mode other than the normal rqmode. It's a
2256 * simple way to provide a big optimization to applications that can
2257 * use them.
2258 */
2259
2260 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
2261 alt = DLM_LOCK_PR;
2262 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
2263 alt = DLM_LOCK_CW;
2264
2265 if (alt) {
2266 lkb->lkb_rqmode = alt;
2267 rv = _can_be_granted(r, lkb, now, 0);
2268 if (rv)
2269 set_bit(DLM_SBF_ALTMODE_BIT, &lkb->lkb_sbflags);
2270 else
2271 lkb->lkb_rqmode = rqmode;
2272 }
2273 out:
2274 return rv;
2275}
2276
2277/* Returns the highest requested mode of all blocked conversions; sets
2278 cw if there's a blocked conversion to DLM_LOCK_CW. */
2279
2280static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2281 unsigned int *count)
2282{
2283 struct dlm_lkb *lkb, *s;
2284 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
2285 int hi, demoted, quit, grant_restart, demote_restart;
2286 int deadlk;
2287
2288 quit = 0;
2289 restart:
2290 grant_restart = 0;
2291 demote_restart = 0;
2292 hi = DLM_LOCK_IV;
2293
2294 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2295 demoted = is_demoted(lkb);
2296 deadlk = 0;
2297
2298 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
2299 grant_lock_pending(r, lkb);
2300 grant_restart = 1;
2301 if (count)
2302 (*count)++;
2303 continue;
2304 }
2305
2306 if (!demoted && is_demoted(lkb)) {
2307 log_print("WARN: pending demoted %x node %d %s",
2308 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2309 demote_restart = 1;
2310 continue;
2311 }
2312
2313 if (deadlk) {
2314 /*
2315 * If DLM_LKB_NODLKWT flag is set and conversion
2316 * deadlock is detected, we request blocking AST and
2317 * down (or cancel) conversion.
2318 */
2319 if (lkb->lkb_exflags & DLM_LKF_NODLCKWT) {
2320 if (lkb->lkb_highbast < lkb->lkb_rqmode) {
2321 queue_bast(r, lkb, lkb->lkb_rqmode);
2322 lkb->lkb_highbast = lkb->lkb_rqmode;
2323 }
2324 } else {
2325 log_print("WARN: pending deadlock %x node %d %s",
2326 lkb->lkb_id, lkb->lkb_nodeid,
2327 r->res_name);
2328 dlm_dump_rsb(r);
2329 }
2330 continue;
2331 }
2332
2333 hi = max_t(int, lkb->lkb_rqmode, hi);
2334
2335 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2336 *cw = 1;
2337 }
2338
2339 if (grant_restart)
2340 goto restart;
2341 if (demote_restart && !quit) {
2342 quit = 1;
2343 goto restart;
2344 }
2345
2346 return max_t(int, high, hi);
2347}
2348
2349static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2350 unsigned int *count)
2351{
2352 struct dlm_lkb *lkb, *s;
2353
2354 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
2355 if (can_be_granted(r, lkb, 0, 0, NULL)) {
2356 grant_lock_pending(r, lkb);
2357 if (count)
2358 (*count)++;
2359 } else {
2360 high = max_t(int, lkb->lkb_rqmode, high);
2361 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2362 *cw = 1;
2363 }
2364 }
2365
2366 return high;
2367}
2368
2369/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2370 on either the convert or waiting queue.
2371 high is the largest rqmode of all locks blocked on the convert or
2372 waiting queue. */
2373
2374static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2375{
2376 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2377 if (gr->lkb_highbast < DLM_LOCK_EX)
2378 return 1;
2379 return 0;
2380 }
2381
2382 if (gr->lkb_highbast < high &&
2383 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2384 return 1;
2385 return 0;
2386}
2387
2388static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
2389{
2390 struct dlm_lkb *lkb, *s;
2391 int high = DLM_LOCK_IV;
2392 int cw = 0;
2393
2394 if (!is_master(r)) {
2395 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2396 dlm_dump_rsb(r);
2397 return;
2398 }
2399
2400 high = grant_pending_convert(r, high, &cw, count);
2401 high = grant_pending_wait(r, high, &cw, count);
2402
2403 if (high == DLM_LOCK_IV)
2404 return;
2405
2406 /*
2407 * If there are locks left on the wait/convert queue then send blocking
2408 * ASTs to granted locks based on the largest requested mode (high)
2409 * found above.
2410 */
2411
2412 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
2413 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
2414 if (cw && high == DLM_LOCK_PR &&
2415 lkb->lkb_grmode == DLM_LOCK_PR)
2416 queue_bast(r, lkb, DLM_LOCK_CW);
2417 else
2418 queue_bast(r, lkb, high);
2419 lkb->lkb_highbast = high;
2420 }
2421 }
2422}
2423
2424static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2425{
2426 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2427 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2428 if (gr->lkb_highbast < DLM_LOCK_EX)
2429 return 1;
2430 return 0;
2431 }
2432
2433 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2434 return 1;
2435 return 0;
2436}
2437
2438static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2439 struct dlm_lkb *lkb)
2440{
2441 struct dlm_lkb *gr;
2442
2443 list_for_each_entry(gr, head, lkb_statequeue) {
2444 /* skip self when sending basts to convertqueue */
2445 if (gr == lkb)
2446 continue;
2447 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
2448 queue_bast(r, gr, lkb->lkb_rqmode);
2449 gr->lkb_highbast = lkb->lkb_rqmode;
2450 }
2451 }
2452}
2453
2454static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2455{
2456 send_bast_queue(r, &r->res_grantqueue, lkb);
2457}
2458
2459static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2460{
2461 send_bast_queue(r, &r->res_grantqueue, lkb);
2462 send_bast_queue(r, &r->res_convertqueue, lkb);
2463}
2464
2465/* set_master(r, lkb) -- set the master nodeid of a resource
2466
2467 The purpose of this function is to set the nodeid field in the given
2468 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2469 known, it can just be copied to the lkb and the function will return
2470 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2471 before it can be copied to the lkb.
2472
2473 When the rsb nodeid is being looked up remotely, the initial lkb
2474 causing the lookup is kept on the ls_waiters list waiting for the
2475 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2476 on the rsb's res_lookup list until the master is verified.
2477
2478 Return values:
2479 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2480 1: the rsb master is not available and the lkb has been placed on
2481 a wait queue
2482*/
2483
2484static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2485{
2486 int our_nodeid = dlm_our_nodeid();
2487
2488 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2489 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2490 r->res_first_lkid = lkb->lkb_id;
2491 lkb->lkb_nodeid = r->res_nodeid;
2492 return 0;
2493 }
2494
2495 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2496 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2497 return 1;
2498 }
2499
2500 if (r->res_master_nodeid == our_nodeid) {
2501 lkb->lkb_nodeid = 0;
2502 return 0;
2503 }
2504
2505 if (r->res_master_nodeid) {
2506 lkb->lkb_nodeid = r->res_master_nodeid;
2507 return 0;
2508 }
2509
2510 if (dlm_dir_nodeid(r) == our_nodeid) {
2511 /* This is a somewhat unusual case; find_rsb will usually
2512 have set res_master_nodeid when dir nodeid is local, but
2513 there are cases where we become the dir node after we've
2514 past find_rsb and go through _request_lock again.
2515 confirm_master() or process_lookup_list() needs to be
2516 called after this. */
2517 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2518 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2519 r->res_name);
2520 r->res_master_nodeid = our_nodeid;
2521 r->res_nodeid = 0;
2522 lkb->lkb_nodeid = 0;
2523 return 0;
2524 }
2525
2526 r->res_first_lkid = lkb->lkb_id;
2527 send_lookup(r, lkb);
2528 return 1;
2529}
2530
2531static void process_lookup_list(struct dlm_rsb *r)
2532{
2533 struct dlm_lkb *lkb, *safe;
2534
2535 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
2536 list_del_init(&lkb->lkb_rsb_lookup);
2537 _request_lock(r, lkb);
2538 schedule();
2539 }
2540}
2541
2542/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2543
2544static void confirm_master(struct dlm_rsb *r, int error)
2545{
2546 struct dlm_lkb *lkb;
2547
2548 if (!r->res_first_lkid)
2549 return;
2550
2551 switch (error) {
2552 case 0:
2553 case -EINPROGRESS:
2554 r->res_first_lkid = 0;
2555 process_lookup_list(r);
2556 break;
2557
2558 case -EAGAIN:
2559 case -EBADR:
2560 case -ENOTBLK:
2561 /* the remote request failed and won't be retried (it was
2562 a NOQUEUE, or has been canceled/unlocked); make a waiting
2563 lkb the first_lkid */
2564
2565 r->res_first_lkid = 0;
2566
2567 if (!list_empty(&r->res_lookup)) {
2568 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2569 lkb_rsb_lookup);
2570 list_del_init(&lkb->lkb_rsb_lookup);
2571 r->res_first_lkid = lkb->lkb_id;
2572 _request_lock(r, lkb);
2573 }
2574 break;
2575
2576 default:
2577 log_error(r->res_ls, "confirm_master unknown error %d", error);
2578 }
2579}
2580
2581static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
2582 int namelen, void (*ast)(void *astparam),
2583 void *astparam,
2584 void (*bast)(void *astparam, int mode),
2585 struct dlm_args *args)
2586{
2587 int rv = -EINVAL;
2588
2589 /* check for invalid arg usage */
2590
2591 if (mode < 0 || mode > DLM_LOCK_EX)
2592 goto out;
2593
2594 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2595 goto out;
2596
2597 if (flags & DLM_LKF_CANCEL)
2598 goto out;
2599
2600 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2601 goto out;
2602
2603 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2604 goto out;
2605
2606 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2607 goto out;
2608
2609 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2610 goto out;
2611
2612 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2613 goto out;
2614
2615 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2616 goto out;
2617
2618 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2619 goto out;
2620
2621 if (!ast || !lksb)
2622 goto out;
2623
2624 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2625 goto out;
2626
2627 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2628 goto out;
2629
2630 /* these args will be copied to the lkb in validate_lock_args,
2631 it cannot be done now because when converting locks, fields in
2632 an active lkb cannot be modified before locking the rsb */
2633
2634 args->flags = flags;
2635 args->astfn = ast;
2636 args->astparam = astparam;
2637 args->bastfn = bast;
2638 args->mode = mode;
2639 args->lksb = lksb;
2640 rv = 0;
2641 out:
2642 return rv;
2643}
2644
2645static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2646{
2647 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2648 DLM_LKF_FORCEUNLOCK))
2649 return -EINVAL;
2650
2651 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2652 return -EINVAL;
2653
2654 args->flags = flags;
2655 args->astparam = astarg;
2656 return 0;
2657}
2658
2659static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2660 struct dlm_args *args)
2661{
2662 int rv = -EBUSY;
2663
2664 if (args->flags & DLM_LKF_CONVERT) {
2665 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2666 goto out;
2667
2668 /* lock not allowed if there's any op in progress */
2669 if (lkb->lkb_wait_type || atomic_read(&lkb->lkb_wait_count))
2670 goto out;
2671
2672 if (is_overlap(lkb))
2673 goto out;
2674
2675 rv = -EINVAL;
2676 if (test_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags))
2677 goto out;
2678
2679 if (args->flags & DLM_LKF_QUECVT &&
2680 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2681 goto out;
2682 }
2683
2684 lkb->lkb_exflags = args->flags;
2685 dlm_set_sbflags_val(lkb, 0);
2686 lkb->lkb_astfn = args->astfn;
2687 lkb->lkb_astparam = args->astparam;
2688 lkb->lkb_bastfn = args->bastfn;
2689 lkb->lkb_rqmode = args->mode;
2690 lkb->lkb_lksb = args->lksb;
2691 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2692 lkb->lkb_ownpid = (int) current->pid;
2693 rv = 0;
2694 out:
2695 switch (rv) {
2696 case 0:
2697 break;
2698 case -EINVAL:
2699 /* annoy the user because dlm usage is wrong */
2700 WARN_ON(1);
2701 log_error(ls, "%s %d %x %x %x %d %d %s", __func__,
2702 rv, lkb->lkb_id, dlm_iflags_val(lkb), args->flags,
2703 lkb->lkb_status, lkb->lkb_wait_type,
2704 lkb->lkb_resource->res_name);
2705 break;
2706 default:
2707 log_debug(ls, "%s %d %x %x %x %d %d %s", __func__,
2708 rv, lkb->lkb_id, dlm_iflags_val(lkb), args->flags,
2709 lkb->lkb_status, lkb->lkb_wait_type,
2710 lkb->lkb_resource->res_name);
2711 break;
2712 }
2713
2714 return rv;
2715}
2716
2717/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2718 for success */
2719
2720/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2721 because there may be a lookup in progress and it's valid to do
2722 cancel/unlockf on it */
2723
2724static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2725{
2726 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
2727 int rv = -EBUSY;
2728
2729 /* normal unlock not allowed if there's any op in progress */
2730 if (!(args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) &&
2731 (lkb->lkb_wait_type || atomic_read(&lkb->lkb_wait_count)))
2732 goto out;
2733
2734 /* an lkb may be waiting for an rsb lookup to complete where the
2735 lookup was initiated by another lock */
2736
2737 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2738 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
2739 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2740 list_del_init(&lkb->lkb_rsb_lookup);
2741 queue_cast(lkb->lkb_resource, lkb,
2742 args->flags & DLM_LKF_CANCEL ?
2743 -DLM_ECANCEL : -DLM_EUNLOCK);
2744 unhold_lkb(lkb); /* undoes create_lkb() */
2745 }
2746 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2747 goto out;
2748 }
2749
2750 rv = -EINVAL;
2751 if (test_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags)) {
2752 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2753 dlm_print_lkb(lkb);
2754 goto out;
2755 }
2756
2757 /* an lkb may still exist even though the lock is EOL'ed due to a
2758 * cancel, unlock or failed noqueue request; an app can't use these
2759 * locks; return same error as if the lkid had not been found at all
2760 */
2761
2762 if (test_bit(DLM_IFL_ENDOFLIFE_BIT, &lkb->lkb_iflags)) {
2763 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2764 rv = -ENOENT;
2765 goto out;
2766 }
2767
2768 /* cancel not allowed with another cancel/unlock in progress */
2769
2770 if (args->flags & DLM_LKF_CANCEL) {
2771 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2772 goto out;
2773
2774 if (is_overlap(lkb))
2775 goto out;
2776
2777 if (test_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags)) {
2778 set_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
2779 rv = -EBUSY;
2780 goto out;
2781 }
2782
2783 /* there's nothing to cancel */
2784 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2785 !lkb->lkb_wait_type) {
2786 rv = -EBUSY;
2787 goto out;
2788 }
2789
2790 switch (lkb->lkb_wait_type) {
2791 case DLM_MSG_LOOKUP:
2792 case DLM_MSG_REQUEST:
2793 set_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
2794 rv = -EBUSY;
2795 goto out;
2796 case DLM_MSG_UNLOCK:
2797 case DLM_MSG_CANCEL:
2798 goto out;
2799 }
2800 /* add_to_waiters() will set OVERLAP_CANCEL */
2801 goto out_ok;
2802 }
2803
2804 /* do we need to allow a force-unlock if there's a normal unlock
2805 already in progress? in what conditions could the normal unlock
2806 fail such that we'd want to send a force-unlock to be sure? */
2807
2808 if (args->flags & DLM_LKF_FORCEUNLOCK) {
2809 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
2810 goto out;
2811
2812 if (is_overlap_unlock(lkb))
2813 goto out;
2814
2815 if (test_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags)) {
2816 set_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
2817 rv = -EBUSY;
2818 goto out;
2819 }
2820
2821 switch (lkb->lkb_wait_type) {
2822 case DLM_MSG_LOOKUP:
2823 case DLM_MSG_REQUEST:
2824 set_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
2825 rv = -EBUSY;
2826 goto out;
2827 case DLM_MSG_UNLOCK:
2828 goto out;
2829 }
2830 /* add_to_waiters() will set OVERLAP_UNLOCK */
2831 }
2832
2833 out_ok:
2834 /* an overlapping op shouldn't blow away exflags from other op */
2835 lkb->lkb_exflags |= args->flags;
2836 dlm_set_sbflags_val(lkb, 0);
2837 lkb->lkb_astparam = args->astparam;
2838 rv = 0;
2839 out:
2840 switch (rv) {
2841 case 0:
2842 break;
2843 case -EINVAL:
2844 /* annoy the user because dlm usage is wrong */
2845 WARN_ON(1);
2846 log_error(ls, "%s %d %x %x %x %x %d %s", __func__, rv,
2847 lkb->lkb_id, dlm_iflags_val(lkb), lkb->lkb_exflags,
2848 args->flags, lkb->lkb_wait_type,
2849 lkb->lkb_resource->res_name);
2850 break;
2851 default:
2852 log_debug(ls, "%s %d %x %x %x %x %d %s", __func__, rv,
2853 lkb->lkb_id, dlm_iflags_val(lkb), lkb->lkb_exflags,
2854 args->flags, lkb->lkb_wait_type,
2855 lkb->lkb_resource->res_name);
2856 break;
2857 }
2858
2859 return rv;
2860}
2861
2862/*
2863 * Four stage 4 varieties:
2864 * do_request(), do_convert(), do_unlock(), do_cancel()
2865 * These are called on the master node for the given lock and
2866 * from the central locking logic.
2867 */
2868
2869static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2870{
2871 int error = 0;
2872
2873 if (can_be_granted(r, lkb, 1, 0, NULL)) {
2874 grant_lock(r, lkb);
2875 queue_cast(r, lkb, 0);
2876 goto out;
2877 }
2878
2879 if (can_be_queued(lkb)) {
2880 error = -EINPROGRESS;
2881 add_lkb(r, lkb, DLM_LKSTS_WAITING);
2882 goto out;
2883 }
2884
2885 error = -EAGAIN;
2886 queue_cast(r, lkb, -EAGAIN);
2887 out:
2888 return error;
2889}
2890
2891static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2892 int error)
2893{
2894 switch (error) {
2895 case -EAGAIN:
2896 if (force_blocking_asts(lkb))
2897 send_blocking_asts_all(r, lkb);
2898 break;
2899 case -EINPROGRESS:
2900 send_blocking_asts(r, lkb);
2901 break;
2902 }
2903}
2904
2905static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2906{
2907 int error = 0;
2908 int deadlk = 0;
2909
2910 /* changing an existing lock may allow others to be granted */
2911
2912 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
2913 grant_lock(r, lkb);
2914 queue_cast(r, lkb, 0);
2915 goto out;
2916 }
2917
2918 /* can_be_granted() detected that this lock would block in a conversion
2919 deadlock, so we leave it on the granted queue and return EDEADLK in
2920 the ast for the convert. */
2921
2922 if (deadlk && !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
2923 /* it's left on the granted queue */
2924 revert_lock(r, lkb);
2925 queue_cast(r, lkb, -EDEADLK);
2926 error = -EDEADLK;
2927 goto out;
2928 }
2929
2930 /* is_demoted() means the can_be_granted() above set the grmode
2931 to NL, and left us on the granted queue. This auto-demotion
2932 (due to CONVDEADLK) might mean other locks, and/or this lock, are
2933 now grantable. We have to try to grant other converting locks
2934 before we try again to grant this one. */
2935
2936 if (is_demoted(lkb)) {
2937 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
2938 if (_can_be_granted(r, lkb, 1, 0)) {
2939 grant_lock(r, lkb);
2940 queue_cast(r, lkb, 0);
2941 goto out;
2942 }
2943 /* else fall through and move to convert queue */
2944 }
2945
2946 if (can_be_queued(lkb)) {
2947 error = -EINPROGRESS;
2948 del_lkb(r, lkb);
2949 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
2950 goto out;
2951 }
2952
2953 error = -EAGAIN;
2954 queue_cast(r, lkb, -EAGAIN);
2955 out:
2956 return error;
2957}
2958
2959static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2960 int error)
2961{
2962 switch (error) {
2963 case 0:
2964 grant_pending_locks(r, NULL);
2965 /* grant_pending_locks also sends basts */
2966 break;
2967 case -EAGAIN:
2968 if (force_blocking_asts(lkb))
2969 send_blocking_asts_all(r, lkb);
2970 break;
2971 case -EINPROGRESS:
2972 send_blocking_asts(r, lkb);
2973 break;
2974 }
2975}
2976
2977static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2978{
2979 remove_lock(r, lkb);
2980 queue_cast(r, lkb, -DLM_EUNLOCK);
2981 return -DLM_EUNLOCK;
2982}
2983
2984static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2985 int error)
2986{
2987 grant_pending_locks(r, NULL);
2988}
2989
2990/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
2991
2992static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2993{
2994 int error;
2995
2996 error = revert_lock(r, lkb);
2997 if (error) {
2998 queue_cast(r, lkb, -DLM_ECANCEL);
2999 return -DLM_ECANCEL;
3000 }
3001 return 0;
3002}
3003
3004static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3005 int error)
3006{
3007 if (error)
3008 grant_pending_locks(r, NULL);
3009}
3010
3011/*
3012 * Four stage 3 varieties:
3013 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3014 */
3015
3016/* add a new lkb to a possibly new rsb, called by requesting process */
3017
3018static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3019{
3020 int error;
3021
3022 /* set_master: sets lkb nodeid from r */
3023
3024 error = set_master(r, lkb);
3025 if (error < 0)
3026 goto out;
3027 if (error) {
3028 error = 0;
3029 goto out;
3030 }
3031
3032 if (is_remote(r)) {
3033 /* receive_request() calls do_request() on remote node */
3034 error = send_request(r, lkb);
3035 } else {
3036 error = do_request(r, lkb);
3037 /* for remote locks the request_reply is sent
3038 between do_request and do_request_effects */
3039 do_request_effects(r, lkb, error);
3040 }
3041 out:
3042 return error;
3043}
3044
3045/* change some property of an existing lkb, e.g. mode */
3046
3047static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3048{
3049 int error;
3050
3051 if (is_remote(r)) {
3052 /* receive_convert() calls do_convert() on remote node */
3053 error = send_convert(r, lkb);
3054 } else {
3055 error = do_convert(r, lkb);
3056 /* for remote locks the convert_reply is sent
3057 between do_convert and do_convert_effects */
3058 do_convert_effects(r, lkb, error);
3059 }
3060
3061 return error;
3062}
3063
3064/* remove an existing lkb from the granted queue */
3065
3066static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3067{
3068 int error;
3069
3070 if (is_remote(r)) {
3071 /* receive_unlock() calls do_unlock() on remote node */
3072 error = send_unlock(r, lkb);
3073 } else {
3074 error = do_unlock(r, lkb);
3075 /* for remote locks the unlock_reply is sent
3076 between do_unlock and do_unlock_effects */
3077 do_unlock_effects(r, lkb, error);
3078 }
3079
3080 return error;
3081}
3082
3083/* remove an existing lkb from the convert or wait queue */
3084
3085static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3086{
3087 int error;
3088
3089 if (is_remote(r)) {
3090 /* receive_cancel() calls do_cancel() on remote node */
3091 error = send_cancel(r, lkb);
3092 } else {
3093 error = do_cancel(r, lkb);
3094 /* for remote locks the cancel_reply is sent
3095 between do_cancel and do_cancel_effects */
3096 do_cancel_effects(r, lkb, error);
3097 }
3098
3099 return error;
3100}
3101
3102/*
3103 * Four stage 2 varieties:
3104 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3105 */
3106
3107static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3108 const void *name, int len,
3109 struct dlm_args *args)
3110{
3111 struct dlm_rsb *r;
3112 int error;
3113
3114 error = validate_lock_args(ls, lkb, args);
3115 if (error)
3116 return error;
3117
3118 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
3119 if (error)
3120 return error;
3121
3122 lock_rsb(r);
3123
3124 attach_lkb(r, lkb);
3125 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3126
3127 error = _request_lock(r, lkb);
3128
3129 unlock_rsb(r);
3130 put_rsb(r);
3131 return error;
3132}
3133
3134static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3135 struct dlm_args *args)
3136{
3137 struct dlm_rsb *r;
3138 int error;
3139
3140 r = lkb->lkb_resource;
3141
3142 hold_rsb(r);
3143 lock_rsb(r);
3144
3145 error = validate_lock_args(ls, lkb, args);
3146 if (error)
3147 goto out;
3148
3149 error = _convert_lock(r, lkb);
3150 out:
3151 unlock_rsb(r);
3152 put_rsb(r);
3153 return error;
3154}
3155
3156static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3157 struct dlm_args *args)
3158{
3159 struct dlm_rsb *r;
3160 int error;
3161
3162 r = lkb->lkb_resource;
3163
3164 hold_rsb(r);
3165 lock_rsb(r);
3166
3167 error = validate_unlock_args(lkb, args);
3168 if (error)
3169 goto out;
3170
3171 error = _unlock_lock(r, lkb);
3172 out:
3173 unlock_rsb(r);
3174 put_rsb(r);
3175 return error;
3176}
3177
3178static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3179 struct dlm_args *args)
3180{
3181 struct dlm_rsb *r;
3182 int error;
3183
3184 r = lkb->lkb_resource;
3185
3186 hold_rsb(r);
3187 lock_rsb(r);
3188
3189 error = validate_unlock_args(lkb, args);
3190 if (error)
3191 goto out;
3192
3193 error = _cancel_lock(r, lkb);
3194 out:
3195 unlock_rsb(r);
3196 put_rsb(r);
3197 return error;
3198}
3199
3200/*
3201 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3202 */
3203
3204int dlm_lock(dlm_lockspace_t *lockspace,
3205 int mode,
3206 struct dlm_lksb *lksb,
3207 uint32_t flags,
3208 const void *name,
3209 unsigned int namelen,
3210 uint32_t parent_lkid,
3211 void (*ast) (void *astarg),
3212 void *astarg,
3213 void (*bast) (void *astarg, int mode))
3214{
3215 struct dlm_ls *ls;
3216 struct dlm_lkb *lkb;
3217 struct dlm_args args;
3218 int error, convert = flags & DLM_LKF_CONVERT;
3219
3220 ls = dlm_find_lockspace_local(lockspace);
3221 if (!ls)
3222 return -EINVAL;
3223
3224 dlm_lock_recovery(ls);
3225
3226 if (convert)
3227 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3228 else
3229 error = create_lkb(ls, &lkb);
3230
3231 if (error)
3232 goto out;
3233
3234 trace_dlm_lock_start(ls, lkb, name, namelen, mode, flags);
3235
3236 error = set_lock_args(mode, lksb, flags, namelen, ast, astarg, bast,
3237 &args);
3238 if (error)
3239 goto out_put;
3240
3241 if (convert)
3242 error = convert_lock(ls, lkb, &args);
3243 else
3244 error = request_lock(ls, lkb, name, namelen, &args);
3245
3246 if (error == -EINPROGRESS)
3247 error = 0;
3248 out_put:
3249 trace_dlm_lock_end(ls, lkb, name, namelen, mode, flags, error, true);
3250
3251 if (convert || error)
3252 __put_lkb(ls, lkb);
3253 if (error == -EAGAIN || error == -EDEADLK)
3254 error = 0;
3255 out:
3256 dlm_unlock_recovery(ls);
3257 dlm_put_lockspace(ls);
3258 return error;
3259}
3260
3261int dlm_unlock(dlm_lockspace_t *lockspace,
3262 uint32_t lkid,
3263 uint32_t flags,
3264 struct dlm_lksb *lksb,
3265 void *astarg)
3266{
3267 struct dlm_ls *ls;
3268 struct dlm_lkb *lkb;
3269 struct dlm_args args;
3270 int error;
3271
3272 ls = dlm_find_lockspace_local(lockspace);
3273 if (!ls)
3274 return -EINVAL;
3275
3276 dlm_lock_recovery(ls);
3277
3278 error = find_lkb(ls, lkid, &lkb);
3279 if (error)
3280 goto out;
3281
3282 trace_dlm_unlock_start(ls, lkb, flags);
3283
3284 error = set_unlock_args(flags, astarg, &args);
3285 if (error)
3286 goto out_put;
3287
3288 if (flags & DLM_LKF_CANCEL)
3289 error = cancel_lock(ls, lkb, &args);
3290 else
3291 error = unlock_lock(ls, lkb, &args);
3292
3293 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3294 error = 0;
3295 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3296 error = 0;
3297 out_put:
3298 trace_dlm_unlock_end(ls, lkb, flags, error);
3299
3300 dlm_put_lkb(lkb);
3301 out:
3302 dlm_unlock_recovery(ls);
3303 dlm_put_lockspace(ls);
3304 return error;
3305}
3306
3307/*
3308 * send/receive routines for remote operations and replies
3309 *
3310 * send_args
3311 * send_common
3312 * send_request receive_request
3313 * send_convert receive_convert
3314 * send_unlock receive_unlock
3315 * send_cancel receive_cancel
3316 * send_grant receive_grant
3317 * send_bast receive_bast
3318 * send_lookup receive_lookup
3319 * send_remove receive_remove
3320 *
3321 * send_common_reply
3322 * receive_request_reply send_request_reply
3323 * receive_convert_reply send_convert_reply
3324 * receive_unlock_reply send_unlock_reply
3325 * receive_cancel_reply send_cancel_reply
3326 * receive_lookup_reply send_lookup_reply
3327 */
3328
3329static int _create_message(struct dlm_ls *ls, int mb_len,
3330 int to_nodeid, int mstype,
3331 struct dlm_message **ms_ret,
3332 struct dlm_mhandle **mh_ret,
3333 gfp_t allocation)
3334{
3335 struct dlm_message *ms;
3336 struct dlm_mhandle *mh;
3337 char *mb;
3338
3339 /* get_buffer gives us a message handle (mh) that we need to
3340 pass into midcomms_commit and a message buffer (mb) that we
3341 write our data into */
3342
3343 mh = dlm_midcomms_get_mhandle(to_nodeid, mb_len, allocation, &mb);
3344 if (!mh)
3345 return -ENOBUFS;
3346
3347 ms = (struct dlm_message *) mb;
3348
3349 ms->m_header.h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
3350 ms->m_header.u.h_lockspace = cpu_to_le32(ls->ls_global_id);
3351 ms->m_header.h_nodeid = cpu_to_le32(dlm_our_nodeid());
3352 ms->m_header.h_length = cpu_to_le16(mb_len);
3353 ms->m_header.h_cmd = DLM_MSG;
3354
3355 ms->m_type = cpu_to_le32(mstype);
3356
3357 *mh_ret = mh;
3358 *ms_ret = ms;
3359 return 0;
3360}
3361
3362static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3363 int to_nodeid, int mstype,
3364 struct dlm_message **ms_ret,
3365 struct dlm_mhandle **mh_ret,
3366 gfp_t allocation)
3367{
3368 int mb_len = sizeof(struct dlm_message);
3369
3370 switch (mstype) {
3371 case DLM_MSG_REQUEST:
3372 case DLM_MSG_LOOKUP:
3373 case DLM_MSG_REMOVE:
3374 mb_len += r->res_length;
3375 break;
3376 case DLM_MSG_CONVERT:
3377 case DLM_MSG_UNLOCK:
3378 case DLM_MSG_REQUEST_REPLY:
3379 case DLM_MSG_CONVERT_REPLY:
3380 case DLM_MSG_GRANT:
3381 if (lkb && lkb->lkb_lvbptr && (lkb->lkb_exflags & DLM_LKF_VALBLK))
3382 mb_len += r->res_ls->ls_lvblen;
3383 break;
3384 }
3385
3386 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3387 ms_ret, mh_ret, allocation);
3388}
3389
3390/* further lowcomms enhancements or alternate implementations may make
3391 the return value from this function useful at some point */
3392
3393static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms,
3394 const void *name, int namelen)
3395{
3396 dlm_midcomms_commit_mhandle(mh, name, namelen);
3397 return 0;
3398}
3399
3400static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3401 struct dlm_message *ms)
3402{
3403 ms->m_nodeid = cpu_to_le32(lkb->lkb_nodeid);
3404 ms->m_pid = cpu_to_le32(lkb->lkb_ownpid);
3405 ms->m_lkid = cpu_to_le32(lkb->lkb_id);
3406 ms->m_remid = cpu_to_le32(lkb->lkb_remid);
3407 ms->m_exflags = cpu_to_le32(lkb->lkb_exflags);
3408 ms->m_sbflags = cpu_to_le32(dlm_sbflags_val(lkb));
3409 ms->m_flags = cpu_to_le32(dlm_dflags_val(lkb));
3410 ms->m_lvbseq = cpu_to_le32(lkb->lkb_lvbseq);
3411 ms->m_status = cpu_to_le32(lkb->lkb_status);
3412 ms->m_grmode = cpu_to_le32(lkb->lkb_grmode);
3413 ms->m_rqmode = cpu_to_le32(lkb->lkb_rqmode);
3414 ms->m_hash = cpu_to_le32(r->res_hash);
3415
3416 /* m_result and m_bastmode are set from function args,
3417 not from lkb fields */
3418
3419 if (lkb->lkb_bastfn)
3420 ms->m_asts |= cpu_to_le32(DLM_CB_BAST);
3421 if (lkb->lkb_astfn)
3422 ms->m_asts |= cpu_to_le32(DLM_CB_CAST);
3423
3424 /* compare with switch in create_message; send_remove() doesn't
3425 use send_args() */
3426
3427 switch (ms->m_type) {
3428 case cpu_to_le32(DLM_MSG_REQUEST):
3429 case cpu_to_le32(DLM_MSG_LOOKUP):
3430 memcpy(ms->m_extra, r->res_name, r->res_length);
3431 break;
3432 case cpu_to_le32(DLM_MSG_CONVERT):
3433 case cpu_to_le32(DLM_MSG_UNLOCK):
3434 case cpu_to_le32(DLM_MSG_REQUEST_REPLY):
3435 case cpu_to_le32(DLM_MSG_CONVERT_REPLY):
3436 case cpu_to_le32(DLM_MSG_GRANT):
3437 if (!lkb->lkb_lvbptr || !(lkb->lkb_exflags & DLM_LKF_VALBLK))
3438 break;
3439 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
3440 break;
3441 }
3442}
3443
3444static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3445{
3446 struct dlm_message *ms;
3447 struct dlm_mhandle *mh;
3448 int to_nodeid, error;
3449
3450 to_nodeid = r->res_nodeid;
3451
3452 error = add_to_waiters(lkb, mstype, to_nodeid);
3453 if (error)
3454 return error;
3455
3456 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh, GFP_NOFS);
3457 if (error)
3458 goto fail;
3459
3460 send_args(r, lkb, ms);
3461
3462 error = send_message(mh, ms, r->res_name, r->res_length);
3463 if (error)
3464 goto fail;
3465 return 0;
3466
3467 fail:
3468 remove_from_waiters(lkb, msg_reply_type(mstype));
3469 return error;
3470}
3471
3472static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3473{
3474 return send_common(r, lkb, DLM_MSG_REQUEST);
3475}
3476
3477static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3478{
3479 int error;
3480
3481 error = send_common(r, lkb, DLM_MSG_CONVERT);
3482
3483 /* down conversions go without a reply from the master */
3484 if (!error && down_conversion(lkb)) {
3485 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
3486 r->res_ls->ls_local_ms.m_type = cpu_to_le32(DLM_MSG_CONVERT_REPLY);
3487 r->res_ls->ls_local_ms.m_result = 0;
3488 __receive_convert_reply(r, lkb, &r->res_ls->ls_local_ms, true);
3489 }
3490
3491 return error;
3492}
3493
3494/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3495 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3496 that the master is still correct. */
3497
3498static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3499{
3500 return send_common(r, lkb, DLM_MSG_UNLOCK);
3501}
3502
3503static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3504{
3505 return send_common(r, lkb, DLM_MSG_CANCEL);
3506}
3507
3508static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3509{
3510 struct dlm_message *ms;
3511 struct dlm_mhandle *mh;
3512 int to_nodeid, error;
3513
3514 to_nodeid = lkb->lkb_nodeid;
3515
3516 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh,
3517 GFP_NOFS);
3518 if (error)
3519 goto out;
3520
3521 send_args(r, lkb, ms);
3522
3523 ms->m_result = 0;
3524
3525 error = send_message(mh, ms, r->res_name, r->res_length);
3526 out:
3527 return error;
3528}
3529
3530static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3531{
3532 struct dlm_message *ms;
3533 struct dlm_mhandle *mh;
3534 int to_nodeid, error;
3535
3536 to_nodeid = lkb->lkb_nodeid;
3537
3538 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh,
3539 GFP_NOFS);
3540 if (error)
3541 goto out;
3542
3543 send_args(r, lkb, ms);
3544
3545 ms->m_bastmode = cpu_to_le32(mode);
3546
3547 error = send_message(mh, ms, r->res_name, r->res_length);
3548 out:
3549 return error;
3550}
3551
3552static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3553{
3554 struct dlm_message *ms;
3555 struct dlm_mhandle *mh;
3556 int to_nodeid, error;
3557
3558 to_nodeid = dlm_dir_nodeid(r);
3559
3560 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
3561 if (error)
3562 return error;
3563
3564 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh,
3565 GFP_NOFS);
3566 if (error)
3567 goto fail;
3568
3569 send_args(r, lkb, ms);
3570
3571 error = send_message(mh, ms, r->res_name, r->res_length);
3572 if (error)
3573 goto fail;
3574 return 0;
3575
3576 fail:
3577 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3578 return error;
3579}
3580
3581static int send_remove(struct dlm_rsb *r)
3582{
3583 struct dlm_message *ms;
3584 struct dlm_mhandle *mh;
3585 int to_nodeid, error;
3586
3587 to_nodeid = dlm_dir_nodeid(r);
3588
3589 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh,
3590 GFP_ATOMIC);
3591 if (error)
3592 goto out;
3593
3594 memcpy(ms->m_extra, r->res_name, r->res_length);
3595 ms->m_hash = cpu_to_le32(r->res_hash);
3596
3597 error = send_message(mh, ms, r->res_name, r->res_length);
3598 out:
3599 return error;
3600}
3601
3602static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3603 int mstype, int rv)
3604{
3605 struct dlm_message *ms;
3606 struct dlm_mhandle *mh;
3607 int to_nodeid, error;
3608
3609 to_nodeid = lkb->lkb_nodeid;
3610
3611 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh, GFP_NOFS);
3612 if (error)
3613 goto out;
3614
3615 send_args(r, lkb, ms);
3616
3617 ms->m_result = cpu_to_le32(to_dlm_errno(rv));
3618
3619 error = send_message(mh, ms, r->res_name, r->res_length);
3620 out:
3621 return error;
3622}
3623
3624static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3625{
3626 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3627}
3628
3629static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3630{
3631 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3632}
3633
3634static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3635{
3636 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3637}
3638
3639static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3640{
3641 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3642}
3643
3644static int send_lookup_reply(struct dlm_ls *ls,
3645 const struct dlm_message *ms_in, int ret_nodeid,
3646 int rv)
3647{
3648 struct dlm_rsb *r = &ls->ls_local_rsb;
3649 struct dlm_message *ms;
3650 struct dlm_mhandle *mh;
3651 int error, nodeid = le32_to_cpu(ms_in->m_header.h_nodeid);
3652
3653 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh,
3654 GFP_NOFS);
3655 if (error)
3656 goto out;
3657
3658 ms->m_lkid = ms_in->m_lkid;
3659 ms->m_result = cpu_to_le32(to_dlm_errno(rv));
3660 ms->m_nodeid = cpu_to_le32(ret_nodeid);
3661
3662 error = send_message(mh, ms, ms_in->m_extra, receive_extralen(ms_in));
3663 out:
3664 return error;
3665}
3666
3667/* which args we save from a received message depends heavily on the type
3668 of message, unlike the send side where we can safely send everything about
3669 the lkb for any type of message */
3670
3671static void receive_flags(struct dlm_lkb *lkb, const struct dlm_message *ms)
3672{
3673 lkb->lkb_exflags = le32_to_cpu(ms->m_exflags);
3674 dlm_set_sbflags_val(lkb, le32_to_cpu(ms->m_sbflags));
3675 dlm_set_dflags_val(lkb, le32_to_cpu(ms->m_flags));
3676}
3677
3678static void receive_flags_reply(struct dlm_lkb *lkb,
3679 const struct dlm_message *ms,
3680 bool local)
3681{
3682 if (local)
3683 return;
3684
3685 dlm_set_sbflags_val(lkb, le32_to_cpu(ms->m_sbflags));
3686 dlm_set_dflags_val(lkb, le32_to_cpu(ms->m_flags));
3687}
3688
3689static int receive_extralen(const struct dlm_message *ms)
3690{
3691 return (le16_to_cpu(ms->m_header.h_length) -
3692 sizeof(struct dlm_message));
3693}
3694
3695static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3696 const struct dlm_message *ms)
3697{
3698 int len;
3699
3700 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3701 if (!lkb->lkb_lvbptr)
3702 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3703 if (!lkb->lkb_lvbptr)
3704 return -ENOMEM;
3705 len = receive_extralen(ms);
3706 if (len > ls->ls_lvblen)
3707 len = ls->ls_lvblen;
3708 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3709 }
3710 return 0;
3711}
3712
3713static void fake_bastfn(void *astparam, int mode)
3714{
3715 log_print("fake_bastfn should not be called");
3716}
3717
3718static void fake_astfn(void *astparam)
3719{
3720 log_print("fake_astfn should not be called");
3721}
3722
3723static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3724 const struct dlm_message *ms)
3725{
3726 lkb->lkb_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
3727 lkb->lkb_ownpid = le32_to_cpu(ms->m_pid);
3728 lkb->lkb_remid = le32_to_cpu(ms->m_lkid);
3729 lkb->lkb_grmode = DLM_LOCK_IV;
3730 lkb->lkb_rqmode = le32_to_cpu(ms->m_rqmode);
3731
3732 lkb->lkb_bastfn = (ms->m_asts & cpu_to_le32(DLM_CB_BAST)) ? &fake_bastfn : NULL;
3733 lkb->lkb_astfn = (ms->m_asts & cpu_to_le32(DLM_CB_CAST)) ? &fake_astfn : NULL;
3734
3735 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3736 /* lkb was just created so there won't be an lvb yet */
3737 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3738 if (!lkb->lkb_lvbptr)
3739 return -ENOMEM;
3740 }
3741
3742 return 0;
3743}
3744
3745static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3746 const struct dlm_message *ms)
3747{
3748 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3749 return -EBUSY;
3750
3751 if (receive_lvb(ls, lkb, ms))
3752 return -ENOMEM;
3753
3754 lkb->lkb_rqmode = le32_to_cpu(ms->m_rqmode);
3755 lkb->lkb_lvbseq = le32_to_cpu(ms->m_lvbseq);
3756
3757 return 0;
3758}
3759
3760static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3761 const struct dlm_message *ms)
3762{
3763 if (receive_lvb(ls, lkb, ms))
3764 return -ENOMEM;
3765 return 0;
3766}
3767
3768/* We fill in the local-lkb fields with the info that send_xxxx_reply()
3769 uses to send a reply and that the remote end uses to process the reply. */
3770
3771static void setup_local_lkb(struct dlm_ls *ls, const struct dlm_message *ms)
3772{
3773 struct dlm_lkb *lkb = &ls->ls_local_lkb;
3774 lkb->lkb_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
3775 lkb->lkb_remid = le32_to_cpu(ms->m_lkid);
3776}
3777
3778/* This is called after the rsb is locked so that we can safely inspect
3779 fields in the lkb. */
3780
3781static int validate_message(struct dlm_lkb *lkb, const struct dlm_message *ms)
3782{
3783 int from = le32_to_cpu(ms->m_header.h_nodeid);
3784 int error = 0;
3785
3786 /* currently mixing of user/kernel locks are not supported */
3787 if (ms->m_flags & cpu_to_le32(BIT(DLM_DFL_USER_BIT)) &&
3788 !test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
3789 log_error(lkb->lkb_resource->res_ls,
3790 "got user dlm message for a kernel lock");
3791 error = -EINVAL;
3792 goto out;
3793 }
3794
3795 switch (ms->m_type) {
3796 case cpu_to_le32(DLM_MSG_CONVERT):
3797 case cpu_to_le32(DLM_MSG_UNLOCK):
3798 case cpu_to_le32(DLM_MSG_CANCEL):
3799 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3800 error = -EINVAL;
3801 break;
3802
3803 case cpu_to_le32(DLM_MSG_CONVERT_REPLY):
3804 case cpu_to_le32(DLM_MSG_UNLOCK_REPLY):
3805 case cpu_to_le32(DLM_MSG_CANCEL_REPLY):
3806 case cpu_to_le32(DLM_MSG_GRANT):
3807 case cpu_to_le32(DLM_MSG_BAST):
3808 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3809 error = -EINVAL;
3810 break;
3811
3812 case cpu_to_le32(DLM_MSG_REQUEST_REPLY):
3813 if (!is_process_copy(lkb))
3814 error = -EINVAL;
3815 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3816 error = -EINVAL;
3817 break;
3818
3819 default:
3820 error = -EINVAL;
3821 }
3822
3823out:
3824 if (error)
3825 log_error(lkb->lkb_resource->res_ls,
3826 "ignore invalid message %d from %d %x %x %x %d",
3827 le32_to_cpu(ms->m_type), from, lkb->lkb_id,
3828 lkb->lkb_remid, dlm_iflags_val(lkb),
3829 lkb->lkb_nodeid);
3830 return error;
3831}
3832
3833static int receive_request(struct dlm_ls *ls, const struct dlm_message *ms)
3834{
3835 struct dlm_lkb *lkb;
3836 struct dlm_rsb *r;
3837 int from_nodeid;
3838 int error, namelen = 0;
3839
3840 from_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
3841
3842 error = create_lkb(ls, &lkb);
3843 if (error)
3844 goto fail;
3845
3846 receive_flags(lkb, ms);
3847 set_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags);
3848 error = receive_request_args(ls, lkb, ms);
3849 if (error) {
3850 __put_lkb(ls, lkb);
3851 goto fail;
3852 }
3853
3854 /* The dir node is the authority on whether we are the master
3855 for this rsb or not, so if the master sends us a request, we should
3856 recreate the rsb if we've destroyed it. This race happens when we
3857 send a remove message to the dir node at the same time that the dir
3858 node sends us a request for the rsb. */
3859
3860 namelen = receive_extralen(ms);
3861
3862 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
3863 R_RECEIVE_REQUEST, &r);
3864 if (error) {
3865 __put_lkb(ls, lkb);
3866 goto fail;
3867 }
3868
3869 lock_rsb(r);
3870
3871 if (r->res_master_nodeid != dlm_our_nodeid()) {
3872 error = validate_master_nodeid(ls, r, from_nodeid);
3873 if (error) {
3874 unlock_rsb(r);
3875 put_rsb(r);
3876 __put_lkb(ls, lkb);
3877 goto fail;
3878 }
3879 }
3880
3881 attach_lkb(r, lkb);
3882 error = do_request(r, lkb);
3883 send_request_reply(r, lkb, error);
3884 do_request_effects(r, lkb, error);
3885
3886 unlock_rsb(r);
3887 put_rsb(r);
3888
3889 if (error == -EINPROGRESS)
3890 error = 0;
3891 if (error)
3892 dlm_put_lkb(lkb);
3893 return 0;
3894
3895 fail:
3896 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
3897 and do this receive_request again from process_lookup_list once
3898 we get the lookup reply. This would avoid a many repeated
3899 ENOTBLK request failures when the lookup reply designating us
3900 as master is delayed. */
3901
3902 if (error != -ENOTBLK) {
3903 log_limit(ls, "receive_request %x from %d %d",
3904 le32_to_cpu(ms->m_lkid), from_nodeid, error);
3905 }
3906
3907 setup_local_lkb(ls, ms);
3908 send_request_reply(&ls->ls_local_rsb, &ls->ls_local_lkb, error);
3909 return error;
3910}
3911
3912static int receive_convert(struct dlm_ls *ls, const struct dlm_message *ms)
3913{
3914 struct dlm_lkb *lkb;
3915 struct dlm_rsb *r;
3916 int error, reply = 1;
3917
3918 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
3919 if (error)
3920 goto fail;
3921
3922 if (lkb->lkb_remid != le32_to_cpu(ms->m_lkid)) {
3923 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
3924 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
3925 (unsigned long long)lkb->lkb_recover_seq,
3926 le32_to_cpu(ms->m_header.h_nodeid),
3927 le32_to_cpu(ms->m_lkid));
3928 error = -ENOENT;
3929 dlm_put_lkb(lkb);
3930 goto fail;
3931 }
3932
3933 r = lkb->lkb_resource;
3934
3935 hold_rsb(r);
3936 lock_rsb(r);
3937
3938 error = validate_message(lkb, ms);
3939 if (error)
3940 goto out;
3941
3942 receive_flags(lkb, ms);
3943
3944 error = receive_convert_args(ls, lkb, ms);
3945 if (error) {
3946 send_convert_reply(r, lkb, error);
3947 goto out;
3948 }
3949
3950 reply = !down_conversion(lkb);
3951
3952 error = do_convert(r, lkb);
3953 if (reply)
3954 send_convert_reply(r, lkb, error);
3955 do_convert_effects(r, lkb, error);
3956 out:
3957 unlock_rsb(r);
3958 put_rsb(r);
3959 dlm_put_lkb(lkb);
3960 return 0;
3961
3962 fail:
3963 setup_local_lkb(ls, ms);
3964 send_convert_reply(&ls->ls_local_rsb, &ls->ls_local_lkb, error);
3965 return error;
3966}
3967
3968static int receive_unlock(struct dlm_ls *ls, const struct dlm_message *ms)
3969{
3970 struct dlm_lkb *lkb;
3971 struct dlm_rsb *r;
3972 int error;
3973
3974 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
3975 if (error)
3976 goto fail;
3977
3978 if (lkb->lkb_remid != le32_to_cpu(ms->m_lkid)) {
3979 log_error(ls, "receive_unlock %x remid %x remote %d %x",
3980 lkb->lkb_id, lkb->lkb_remid,
3981 le32_to_cpu(ms->m_header.h_nodeid),
3982 le32_to_cpu(ms->m_lkid));
3983 error = -ENOENT;
3984 dlm_put_lkb(lkb);
3985 goto fail;
3986 }
3987
3988 r = lkb->lkb_resource;
3989
3990 hold_rsb(r);
3991 lock_rsb(r);
3992
3993 error = validate_message(lkb, ms);
3994 if (error)
3995 goto out;
3996
3997 receive_flags(lkb, ms);
3998
3999 error = receive_unlock_args(ls, lkb, ms);
4000 if (error) {
4001 send_unlock_reply(r, lkb, error);
4002 goto out;
4003 }
4004
4005 error = do_unlock(r, lkb);
4006 send_unlock_reply(r, lkb, error);
4007 do_unlock_effects(r, lkb, error);
4008 out:
4009 unlock_rsb(r);
4010 put_rsb(r);
4011 dlm_put_lkb(lkb);
4012 return 0;
4013
4014 fail:
4015 setup_local_lkb(ls, ms);
4016 send_unlock_reply(&ls->ls_local_rsb, &ls->ls_local_lkb, error);
4017 return error;
4018}
4019
4020static int receive_cancel(struct dlm_ls *ls, const struct dlm_message *ms)
4021{
4022 struct dlm_lkb *lkb;
4023 struct dlm_rsb *r;
4024 int error;
4025
4026 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4027 if (error)
4028 goto fail;
4029
4030 receive_flags(lkb, ms);
4031
4032 r = lkb->lkb_resource;
4033
4034 hold_rsb(r);
4035 lock_rsb(r);
4036
4037 error = validate_message(lkb, ms);
4038 if (error)
4039 goto out;
4040
4041 error = do_cancel(r, lkb);
4042 send_cancel_reply(r, lkb, error);
4043 do_cancel_effects(r, lkb, error);
4044 out:
4045 unlock_rsb(r);
4046 put_rsb(r);
4047 dlm_put_lkb(lkb);
4048 return 0;
4049
4050 fail:
4051 setup_local_lkb(ls, ms);
4052 send_cancel_reply(&ls->ls_local_rsb, &ls->ls_local_lkb, error);
4053 return error;
4054}
4055
4056static int receive_grant(struct dlm_ls *ls, const struct dlm_message *ms)
4057{
4058 struct dlm_lkb *lkb;
4059 struct dlm_rsb *r;
4060 int error;
4061
4062 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4063 if (error)
4064 return error;
4065
4066 r = lkb->lkb_resource;
4067
4068 hold_rsb(r);
4069 lock_rsb(r);
4070
4071 error = validate_message(lkb, ms);
4072 if (error)
4073 goto out;
4074
4075 receive_flags_reply(lkb, ms, false);
4076 if (is_altmode(lkb))
4077 munge_altmode(lkb, ms);
4078 grant_lock_pc(r, lkb, ms);
4079 queue_cast(r, lkb, 0);
4080 out:
4081 unlock_rsb(r);
4082 put_rsb(r);
4083 dlm_put_lkb(lkb);
4084 return 0;
4085}
4086
4087static int receive_bast(struct dlm_ls *ls, const struct dlm_message *ms)
4088{
4089 struct dlm_lkb *lkb;
4090 struct dlm_rsb *r;
4091 int error;
4092
4093 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4094 if (error)
4095 return error;
4096
4097 r = lkb->lkb_resource;
4098
4099 hold_rsb(r);
4100 lock_rsb(r);
4101
4102 error = validate_message(lkb, ms);
4103 if (error)
4104 goto out;
4105
4106 queue_bast(r, lkb, le32_to_cpu(ms->m_bastmode));
4107 lkb->lkb_highbast = le32_to_cpu(ms->m_bastmode);
4108 out:
4109 unlock_rsb(r);
4110 put_rsb(r);
4111 dlm_put_lkb(lkb);
4112 return 0;
4113}
4114
4115static void receive_lookup(struct dlm_ls *ls, const struct dlm_message *ms)
4116{
4117 int len, error, ret_nodeid, from_nodeid, our_nodeid;
4118
4119 from_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
4120 our_nodeid = dlm_our_nodeid();
4121
4122 len = receive_extralen(ms);
4123
4124 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4125 &ret_nodeid, NULL);
4126
4127 /* Optimization: we're master so treat lookup as a request */
4128 if (!error && ret_nodeid == our_nodeid) {
4129 receive_request(ls, ms);
4130 return;
4131 }
4132 send_lookup_reply(ls, ms, ret_nodeid, error);
4133}
4134
4135static void receive_remove(struct dlm_ls *ls, const struct dlm_message *ms)
4136{
4137 char name[DLM_RESNAME_MAXLEN+1];
4138 struct dlm_rsb *r;
4139 uint32_t hash, b;
4140 int rv, len, dir_nodeid, from_nodeid;
4141
4142 from_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
4143
4144 len = receive_extralen(ms);
4145
4146 if (len > DLM_RESNAME_MAXLEN) {
4147 log_error(ls, "receive_remove from %d bad len %d",
4148 from_nodeid, len);
4149 return;
4150 }
4151
4152 dir_nodeid = dlm_hash2nodeid(ls, le32_to_cpu(ms->m_hash));
4153 if (dir_nodeid != dlm_our_nodeid()) {
4154 log_error(ls, "receive_remove from %d bad nodeid %d",
4155 from_nodeid, dir_nodeid);
4156 return;
4157 }
4158
4159 /* Look for name on rsbtbl.toss, if it's there, kill it.
4160 If it's on rsbtbl.keep, it's being used, and we should ignore this
4161 message. This is an expected race between the dir node sending a
4162 request to the master node at the same time as the master node sends
4163 a remove to the dir node. The resolution to that race is for the
4164 dir node to ignore the remove message, and the master node to
4165 recreate the master rsb when it gets a request from the dir node for
4166 an rsb it doesn't have. */
4167
4168 memset(name, 0, sizeof(name));
4169 memcpy(name, ms->m_extra, len);
4170
4171 hash = jhash(name, len, 0);
4172 b = hash & (ls->ls_rsbtbl_size - 1);
4173
4174 spin_lock(&ls->ls_rsbtbl[b].lock);
4175
4176 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4177 if (rv) {
4178 /* verify the rsb is on keep list per comment above */
4179 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4180 if (rv) {
4181 /* should not happen */
4182 log_error(ls, "receive_remove from %d not found %s",
4183 from_nodeid, name);
4184 spin_unlock(&ls->ls_rsbtbl[b].lock);
4185 return;
4186 }
4187 if (r->res_master_nodeid != from_nodeid) {
4188 /* should not happen */
4189 log_error(ls, "receive_remove keep from %d master %d",
4190 from_nodeid, r->res_master_nodeid);
4191 dlm_print_rsb(r);
4192 spin_unlock(&ls->ls_rsbtbl[b].lock);
4193 return;
4194 }
4195
4196 log_debug(ls, "receive_remove from %d master %d first %x %s",
4197 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4198 name);
4199 spin_unlock(&ls->ls_rsbtbl[b].lock);
4200 return;
4201 }
4202
4203 if (r->res_master_nodeid != from_nodeid) {
4204 log_error(ls, "receive_remove toss from %d master %d",
4205 from_nodeid, r->res_master_nodeid);
4206 dlm_print_rsb(r);
4207 spin_unlock(&ls->ls_rsbtbl[b].lock);
4208 return;
4209 }
4210
4211 if (kref_put(&r->res_ref, kill_rsb)) {
4212 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4213 spin_unlock(&ls->ls_rsbtbl[b].lock);
4214 dlm_free_rsb(r);
4215 } else {
4216 log_error(ls, "receive_remove from %d rsb ref error",
4217 from_nodeid);
4218 dlm_print_rsb(r);
4219 spin_unlock(&ls->ls_rsbtbl[b].lock);
4220 }
4221}
4222
4223static void receive_purge(struct dlm_ls *ls, const struct dlm_message *ms)
4224{
4225 do_purge(ls, le32_to_cpu(ms->m_nodeid), le32_to_cpu(ms->m_pid));
4226}
4227
4228static int receive_request_reply(struct dlm_ls *ls,
4229 const struct dlm_message *ms)
4230{
4231 struct dlm_lkb *lkb;
4232 struct dlm_rsb *r;
4233 int error, mstype, result;
4234 int from_nodeid = le32_to_cpu(ms->m_header.h_nodeid);
4235
4236 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4237 if (error)
4238 return error;
4239
4240 r = lkb->lkb_resource;
4241 hold_rsb(r);
4242 lock_rsb(r);
4243
4244 error = validate_message(lkb, ms);
4245 if (error)
4246 goto out;
4247
4248 mstype = lkb->lkb_wait_type;
4249 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4250 if (error) {
4251 log_error(ls, "receive_request_reply %x remote %d %x result %d",
4252 lkb->lkb_id, from_nodeid, le32_to_cpu(ms->m_lkid),
4253 from_dlm_errno(le32_to_cpu(ms->m_result)));
4254 dlm_dump_rsb(r);
4255 goto out;
4256 }
4257
4258 /* Optimization: the dir node was also the master, so it took our
4259 lookup as a request and sent request reply instead of lookup reply */
4260 if (mstype == DLM_MSG_LOOKUP) {
4261 r->res_master_nodeid = from_nodeid;
4262 r->res_nodeid = from_nodeid;
4263 lkb->lkb_nodeid = from_nodeid;
4264 }
4265
4266 /* this is the value returned from do_request() on the master */
4267 result = from_dlm_errno(le32_to_cpu(ms->m_result));
4268
4269 switch (result) {
4270 case -EAGAIN:
4271 /* request would block (be queued) on remote master */
4272 queue_cast(r, lkb, -EAGAIN);
4273 confirm_master(r, -EAGAIN);
4274 unhold_lkb(lkb); /* undoes create_lkb() */
4275 break;
4276
4277 case -EINPROGRESS:
4278 case 0:
4279 /* request was queued or granted on remote master */
4280 receive_flags_reply(lkb, ms, false);
4281 lkb->lkb_remid = le32_to_cpu(ms->m_lkid);
4282 if (is_altmode(lkb))
4283 munge_altmode(lkb, ms);
4284 if (result) {
4285 add_lkb(r, lkb, DLM_LKSTS_WAITING);
4286 } else {
4287 grant_lock_pc(r, lkb, ms);
4288 queue_cast(r, lkb, 0);
4289 }
4290 confirm_master(r, result);
4291 break;
4292
4293 case -EBADR:
4294 case -ENOTBLK:
4295 /* find_rsb failed to find rsb or rsb wasn't master */
4296 log_limit(ls, "receive_request_reply %x from %d %d "
4297 "master %d dir %d first %x %s", lkb->lkb_id,
4298 from_nodeid, result, r->res_master_nodeid,
4299 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4300
4301 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4302 r->res_master_nodeid != dlm_our_nodeid()) {
4303 /* cause _request_lock->set_master->send_lookup */
4304 r->res_master_nodeid = 0;
4305 r->res_nodeid = -1;
4306 lkb->lkb_nodeid = -1;
4307 }
4308
4309 if (is_overlap(lkb)) {
4310 /* we'll ignore error in cancel/unlock reply */
4311 queue_cast_overlap(r, lkb);
4312 confirm_master(r, result);
4313 unhold_lkb(lkb); /* undoes create_lkb() */
4314 } else {
4315 _request_lock(r, lkb);
4316
4317 if (r->res_master_nodeid == dlm_our_nodeid())
4318 confirm_master(r, 0);
4319 }
4320 break;
4321
4322 default:
4323 log_error(ls, "receive_request_reply %x error %d",
4324 lkb->lkb_id, result);
4325 }
4326
4327 if ((result == 0 || result == -EINPROGRESS) &&
4328 test_and_clear_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags)) {
4329 log_debug(ls, "receive_request_reply %x result %d unlock",
4330 lkb->lkb_id, result);
4331 clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
4332 send_unlock(r, lkb);
4333 } else if ((result == -EINPROGRESS) &&
4334 test_and_clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT,
4335 &lkb->lkb_iflags)) {
4336 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4337 clear_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
4338 send_cancel(r, lkb);
4339 } else {
4340 clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT, &lkb->lkb_iflags);
4341 clear_bit(DLM_IFL_OVERLAP_UNLOCK_BIT, &lkb->lkb_iflags);
4342 }
4343 out:
4344 unlock_rsb(r);
4345 put_rsb(r);
4346 dlm_put_lkb(lkb);
4347 return 0;
4348}
4349
4350static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4351 const struct dlm_message *ms, bool local)
4352{
4353 /* this is the value returned from do_convert() on the master */
4354 switch (from_dlm_errno(le32_to_cpu(ms->m_result))) {
4355 case -EAGAIN:
4356 /* convert would block (be queued) on remote master */
4357 queue_cast(r, lkb, -EAGAIN);
4358 break;
4359
4360 case -EDEADLK:
4361 receive_flags_reply(lkb, ms, local);
4362 revert_lock_pc(r, lkb);
4363 queue_cast(r, lkb, -EDEADLK);
4364 break;
4365
4366 case -EINPROGRESS:
4367 /* convert was queued on remote master */
4368 receive_flags_reply(lkb, ms, local);
4369 if (is_demoted(lkb))
4370 munge_demoted(lkb);
4371 del_lkb(r, lkb);
4372 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
4373 break;
4374
4375 case 0:
4376 /* convert was granted on remote master */
4377 receive_flags_reply(lkb, ms, local);
4378 if (is_demoted(lkb))
4379 munge_demoted(lkb);
4380 grant_lock_pc(r, lkb, ms);
4381 queue_cast(r, lkb, 0);
4382 break;
4383
4384 default:
4385 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4386 lkb->lkb_id, le32_to_cpu(ms->m_header.h_nodeid),
4387 le32_to_cpu(ms->m_lkid),
4388 from_dlm_errno(le32_to_cpu(ms->m_result)));
4389 dlm_print_rsb(r);
4390 dlm_print_lkb(lkb);
4391 }
4392}
4393
4394static void _receive_convert_reply(struct dlm_lkb *lkb,
4395 const struct dlm_message *ms, bool local)
4396{
4397 struct dlm_rsb *r = lkb->lkb_resource;
4398 int error;
4399
4400 hold_rsb(r);
4401 lock_rsb(r);
4402
4403 error = validate_message(lkb, ms);
4404 if (error)
4405 goto out;
4406
4407 /* local reply can happen with waiters_mutex held */
4408 error = remove_from_waiters_ms(lkb, ms, local);
4409 if (error)
4410 goto out;
4411
4412 __receive_convert_reply(r, lkb, ms, local);
4413 out:
4414 unlock_rsb(r);
4415 put_rsb(r);
4416}
4417
4418static int receive_convert_reply(struct dlm_ls *ls,
4419 const struct dlm_message *ms)
4420{
4421 struct dlm_lkb *lkb;
4422 int error;
4423
4424 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4425 if (error)
4426 return error;
4427
4428 _receive_convert_reply(lkb, ms, false);
4429 dlm_put_lkb(lkb);
4430 return 0;
4431}
4432
4433static void _receive_unlock_reply(struct dlm_lkb *lkb,
4434 const struct dlm_message *ms, bool local)
4435{
4436 struct dlm_rsb *r = lkb->lkb_resource;
4437 int error;
4438
4439 hold_rsb(r);
4440 lock_rsb(r);
4441
4442 error = validate_message(lkb, ms);
4443 if (error)
4444 goto out;
4445
4446 /* local reply can happen with waiters_mutex held */
4447 error = remove_from_waiters_ms(lkb, ms, local);
4448 if (error)
4449 goto out;
4450
4451 /* this is the value returned from do_unlock() on the master */
4452
4453 switch (from_dlm_errno(le32_to_cpu(ms->m_result))) {
4454 case -DLM_EUNLOCK:
4455 receive_flags_reply(lkb, ms, local);
4456 remove_lock_pc(r, lkb);
4457 queue_cast(r, lkb, -DLM_EUNLOCK);
4458 break;
4459 case -ENOENT:
4460 break;
4461 default:
4462 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4463 lkb->lkb_id, from_dlm_errno(le32_to_cpu(ms->m_result)));
4464 }
4465 out:
4466 unlock_rsb(r);
4467 put_rsb(r);
4468}
4469
4470static int receive_unlock_reply(struct dlm_ls *ls,
4471 const struct dlm_message *ms)
4472{
4473 struct dlm_lkb *lkb;
4474 int error;
4475
4476 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4477 if (error)
4478 return error;
4479
4480 _receive_unlock_reply(lkb, ms, false);
4481 dlm_put_lkb(lkb);
4482 return 0;
4483}
4484
4485static void _receive_cancel_reply(struct dlm_lkb *lkb,
4486 const struct dlm_message *ms, bool local)
4487{
4488 struct dlm_rsb *r = lkb->lkb_resource;
4489 int error;
4490
4491 hold_rsb(r);
4492 lock_rsb(r);
4493
4494 error = validate_message(lkb, ms);
4495 if (error)
4496 goto out;
4497
4498 /* local reply can happen with waiters_mutex held */
4499 error = remove_from_waiters_ms(lkb, ms, local);
4500 if (error)
4501 goto out;
4502
4503 /* this is the value returned from do_cancel() on the master */
4504
4505 switch (from_dlm_errno(le32_to_cpu(ms->m_result))) {
4506 case -DLM_ECANCEL:
4507 receive_flags_reply(lkb, ms, local);
4508 revert_lock_pc(r, lkb);
4509 queue_cast(r, lkb, -DLM_ECANCEL);
4510 break;
4511 case 0:
4512 break;
4513 default:
4514 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4515 lkb->lkb_id,
4516 from_dlm_errno(le32_to_cpu(ms->m_result)));
4517 }
4518 out:
4519 unlock_rsb(r);
4520 put_rsb(r);
4521}
4522
4523static int receive_cancel_reply(struct dlm_ls *ls,
4524 const struct dlm_message *ms)
4525{
4526 struct dlm_lkb *lkb;
4527 int error;
4528
4529 error = find_lkb(ls, le32_to_cpu(ms->m_remid), &lkb);
4530 if (error)
4531 return error;
4532
4533 _receive_cancel_reply(lkb, ms, false);
4534 dlm_put_lkb(lkb);
4535 return 0;
4536}
4537
4538static void receive_lookup_reply(struct dlm_ls *ls,
4539 const struct dlm_message *ms)
4540{
4541 struct dlm_lkb *lkb;
4542 struct dlm_rsb *r;
4543 int error, ret_nodeid;
4544 int do_lookup_list = 0;
4545
4546 error = find_lkb(ls, le32_to_cpu(ms->m_lkid), &lkb);
4547 if (error) {
4548 log_error(ls, "%s no lkid %x", __func__,
4549 le32_to_cpu(ms->m_lkid));
4550 return;
4551 }
4552
4553 /* ms->m_result is the value returned by dlm_master_lookup on dir node
4554 FIXME: will a non-zero error ever be returned? */
4555
4556 r = lkb->lkb_resource;
4557 hold_rsb(r);
4558 lock_rsb(r);
4559
4560 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4561 if (error)
4562 goto out;
4563
4564 ret_nodeid = le32_to_cpu(ms->m_nodeid);
4565
4566 /* We sometimes receive a request from the dir node for this
4567 rsb before we've received the dir node's loookup_reply for it.
4568 The request from the dir node implies we're the master, so we set
4569 ourself as master in receive_request_reply, and verify here that
4570 we are indeed the master. */
4571
4572 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4573 /* This should never happen */
4574 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4575 "master %d dir %d our %d first %x %s",
4576 lkb->lkb_id, le32_to_cpu(ms->m_header.h_nodeid),
4577 ret_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
4578 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4579 }
4580
4581 if (ret_nodeid == dlm_our_nodeid()) {
4582 r->res_master_nodeid = ret_nodeid;
4583 r->res_nodeid = 0;
4584 do_lookup_list = 1;
4585 r->res_first_lkid = 0;
4586 } else if (ret_nodeid == -1) {
4587 /* the remote node doesn't believe it's the dir node */
4588 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4589 lkb->lkb_id, le32_to_cpu(ms->m_header.h_nodeid));
4590 r->res_master_nodeid = 0;
4591 r->res_nodeid = -1;
4592 lkb->lkb_nodeid = -1;
4593 } else {
4594 /* set_master() will set lkb_nodeid from r */
4595 r->res_master_nodeid = ret_nodeid;
4596 r->res_nodeid = ret_nodeid;
4597 }
4598
4599 if (is_overlap(lkb)) {
4600 log_debug(ls, "receive_lookup_reply %x unlock %x",
4601 lkb->lkb_id, dlm_iflags_val(lkb));
4602 queue_cast_overlap(r, lkb);
4603 unhold_lkb(lkb); /* undoes create_lkb() */
4604 goto out_list;
4605 }
4606
4607 _request_lock(r, lkb);
4608
4609 out_list:
4610 if (do_lookup_list)
4611 process_lookup_list(r);
4612 out:
4613 unlock_rsb(r);
4614 put_rsb(r);
4615 dlm_put_lkb(lkb);
4616}
4617
4618static void _receive_message(struct dlm_ls *ls, const struct dlm_message *ms,
4619 uint32_t saved_seq)
4620{
4621 int error = 0, noent = 0;
4622
4623 if (WARN_ON_ONCE(!dlm_is_member(ls, le32_to_cpu(ms->m_header.h_nodeid)))) {
4624 log_limit(ls, "receive %d from non-member %d %x %x %d",
4625 le32_to_cpu(ms->m_type),
4626 le32_to_cpu(ms->m_header.h_nodeid),
4627 le32_to_cpu(ms->m_lkid), le32_to_cpu(ms->m_remid),
4628 from_dlm_errno(le32_to_cpu(ms->m_result)));
4629 return;
4630 }
4631
4632 switch (ms->m_type) {
4633
4634 /* messages sent to a master node */
4635
4636 case cpu_to_le32(DLM_MSG_REQUEST):
4637 error = receive_request(ls, ms);
4638 break;
4639
4640 case cpu_to_le32(DLM_MSG_CONVERT):
4641 error = receive_convert(ls, ms);
4642 break;
4643
4644 case cpu_to_le32(DLM_MSG_UNLOCK):
4645 error = receive_unlock(ls, ms);
4646 break;
4647
4648 case cpu_to_le32(DLM_MSG_CANCEL):
4649 noent = 1;
4650 error = receive_cancel(ls, ms);
4651 break;
4652
4653 /* messages sent from a master node (replies to above) */
4654
4655 case cpu_to_le32(DLM_MSG_REQUEST_REPLY):
4656 error = receive_request_reply(ls, ms);
4657 break;
4658
4659 case cpu_to_le32(DLM_MSG_CONVERT_REPLY):
4660 error = receive_convert_reply(ls, ms);
4661 break;
4662
4663 case cpu_to_le32(DLM_MSG_UNLOCK_REPLY):
4664 error = receive_unlock_reply(ls, ms);
4665 break;
4666
4667 case cpu_to_le32(DLM_MSG_CANCEL_REPLY):
4668 error = receive_cancel_reply(ls, ms);
4669 break;
4670
4671 /* messages sent from a master node (only two types of async msg) */
4672
4673 case cpu_to_le32(DLM_MSG_GRANT):
4674 noent = 1;
4675 error = receive_grant(ls, ms);
4676 break;
4677
4678 case cpu_to_le32(DLM_MSG_BAST):
4679 noent = 1;
4680 error = receive_bast(ls, ms);
4681 break;
4682
4683 /* messages sent to a dir node */
4684
4685 case cpu_to_le32(DLM_MSG_LOOKUP):
4686 receive_lookup(ls, ms);
4687 break;
4688
4689 case cpu_to_le32(DLM_MSG_REMOVE):
4690 receive_remove(ls, ms);
4691 break;
4692
4693 /* messages sent from a dir node (remove has no reply) */
4694
4695 case cpu_to_le32(DLM_MSG_LOOKUP_REPLY):
4696 receive_lookup_reply(ls, ms);
4697 break;
4698
4699 /* other messages */
4700
4701 case cpu_to_le32(DLM_MSG_PURGE):
4702 receive_purge(ls, ms);
4703 break;
4704
4705 default:
4706 log_error(ls, "unknown message type %d",
4707 le32_to_cpu(ms->m_type));
4708 }
4709
4710 /*
4711 * When checking for ENOENT, we're checking the result of
4712 * find_lkb(m_remid):
4713 *
4714 * The lock id referenced in the message wasn't found. This may
4715 * happen in normal usage for the async messages and cancel, so
4716 * only use log_debug for them.
4717 *
4718 * Some errors are expected and normal.
4719 */
4720
4721 if (error == -ENOENT && noent) {
4722 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
4723 le32_to_cpu(ms->m_type), le32_to_cpu(ms->m_remid),
4724 le32_to_cpu(ms->m_header.h_nodeid),
4725 le32_to_cpu(ms->m_lkid), saved_seq);
4726 } else if (error == -ENOENT) {
4727 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
4728 le32_to_cpu(ms->m_type), le32_to_cpu(ms->m_remid),
4729 le32_to_cpu(ms->m_header.h_nodeid),
4730 le32_to_cpu(ms->m_lkid), saved_seq);
4731
4732 if (ms->m_type == cpu_to_le32(DLM_MSG_CONVERT))
4733 dlm_dump_rsb_hash(ls, le32_to_cpu(ms->m_hash));
4734 }
4735
4736 if (error == -EINVAL) {
4737 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4738 "saved_seq %u",
4739 le32_to_cpu(ms->m_type),
4740 le32_to_cpu(ms->m_header.h_nodeid),
4741 le32_to_cpu(ms->m_lkid), le32_to_cpu(ms->m_remid),
4742 saved_seq);
4743 }
4744}
4745
4746/* If the lockspace is in recovery mode (locking stopped), then normal
4747 messages are saved on the requestqueue for processing after recovery is
4748 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4749 messages off the requestqueue before we process new ones. This occurs right
4750 after recovery completes when we transition from saving all messages on
4751 requestqueue, to processing all the saved messages, to processing new
4752 messages as they arrive. */
4753
4754static void dlm_receive_message(struct dlm_ls *ls, const struct dlm_message *ms,
4755 int nodeid)
4756{
4757 if (dlm_locking_stopped(ls)) {
4758 /* If we were a member of this lockspace, left, and rejoined,
4759 other nodes may still be sending us messages from the
4760 lockspace generation before we left. */
4761 if (WARN_ON_ONCE(!ls->ls_generation)) {
4762 log_limit(ls, "receive %d from %d ignore old gen",
4763 le32_to_cpu(ms->m_type), nodeid);
4764 return;
4765 }
4766
4767 dlm_add_requestqueue(ls, nodeid, ms);
4768 } else {
4769 dlm_wait_requestqueue(ls);
4770 _receive_message(ls, ms, 0);
4771 }
4772}
4773
4774/* This is called by dlm_recoverd to process messages that were saved on
4775 the requestqueue. */
4776
4777void dlm_receive_message_saved(struct dlm_ls *ls, const struct dlm_message *ms,
4778 uint32_t saved_seq)
4779{
4780 _receive_message(ls, ms, saved_seq);
4781}
4782
4783/* This is called by the midcomms layer when something is received for
4784 the lockspace. It could be either a MSG (normal message sent as part of
4785 standard locking activity) or an RCOM (recovery message sent as part of
4786 lockspace recovery). */
4787
4788void dlm_receive_buffer(const union dlm_packet *p, int nodeid)
4789{
4790 const struct dlm_header *hd = &p->header;
4791 struct dlm_ls *ls;
4792 int type = 0;
4793
4794 switch (hd->h_cmd) {
4795 case DLM_MSG:
4796 type = le32_to_cpu(p->message.m_type);
4797 break;
4798 case DLM_RCOM:
4799 type = le32_to_cpu(p->rcom.rc_type);
4800 break;
4801 default:
4802 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
4803 return;
4804 }
4805
4806 if (le32_to_cpu(hd->h_nodeid) != nodeid) {
4807 log_print("invalid h_nodeid %d from %d lockspace %x",
4808 le32_to_cpu(hd->h_nodeid), nodeid,
4809 le32_to_cpu(hd->u.h_lockspace));
4810 return;
4811 }
4812
4813 ls = dlm_find_lockspace_global(le32_to_cpu(hd->u.h_lockspace));
4814 if (!ls) {
4815 if (dlm_config.ci_log_debug) {
4816 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
4817 "%u from %d cmd %d type %d\n",
4818 le32_to_cpu(hd->u.h_lockspace), nodeid,
4819 hd->h_cmd, type);
4820 }
4821
4822 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
4823 dlm_send_ls_not_ready(nodeid, &p->rcom);
4824 return;
4825 }
4826
4827 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
4828 be inactive (in this ls) before transitioning to recovery mode */
4829
4830 down_read(&ls->ls_recv_active);
4831 if (hd->h_cmd == DLM_MSG)
4832 dlm_receive_message(ls, &p->message, nodeid);
4833 else if (hd->h_cmd == DLM_RCOM)
4834 dlm_receive_rcom(ls, &p->rcom, nodeid);
4835 else
4836 log_error(ls, "invalid h_cmd %d from %d lockspace %x",
4837 hd->h_cmd, nodeid, le32_to_cpu(hd->u.h_lockspace));
4838 up_read(&ls->ls_recv_active);
4839
4840 dlm_put_lockspace(ls);
4841}
4842
4843static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
4844 struct dlm_message *ms_local)
4845{
4846 if (middle_conversion(lkb)) {
4847 hold_lkb(lkb);
4848 memset(ms_local, 0, sizeof(struct dlm_message));
4849 ms_local->m_type = cpu_to_le32(DLM_MSG_CONVERT_REPLY);
4850 ms_local->m_result = cpu_to_le32(to_dlm_errno(-EINPROGRESS));
4851 ms_local->m_header.h_nodeid = cpu_to_le32(lkb->lkb_nodeid);
4852 _receive_convert_reply(lkb, ms_local, true);
4853
4854 /* Same special case as in receive_rcom_lock_args() */
4855 lkb->lkb_grmode = DLM_LOCK_IV;
4856 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
4857 unhold_lkb(lkb);
4858
4859 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
4860 set_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags);
4861 }
4862
4863 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
4864 conversions are async; there's no reply from the remote master */
4865}
4866
4867/* A waiting lkb needs recovery if the master node has failed, or
4868 the master node is changing (only when no directory is used) */
4869
4870static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
4871 int dir_nodeid)
4872{
4873 if (dlm_no_directory(ls))
4874 return 1;
4875
4876 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
4877 return 1;
4878
4879 return 0;
4880}
4881
4882/* Recovery for locks that are waiting for replies from nodes that are now
4883 gone. We can just complete unlocks and cancels by faking a reply from the
4884 dead node. Requests and up-conversions we flag to be resent after
4885 recovery. Down-conversions can just be completed with a fake reply like
4886 unlocks. Conversions between PR and CW need special attention. */
4887
4888void dlm_recover_waiters_pre(struct dlm_ls *ls)
4889{
4890 struct dlm_lkb *lkb, *safe;
4891 struct dlm_message *ms_local;
4892 int wait_type, local_unlock_result, local_cancel_result;
4893 int dir_nodeid;
4894
4895 ms_local = kmalloc(sizeof(*ms_local), GFP_KERNEL);
4896 if (!ms_local)
4897 return;
4898
4899 mutex_lock(&ls->ls_waiters_mutex);
4900
4901 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
4902
4903 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
4904
4905 /* exclude debug messages about unlocks because there can be so
4906 many and they aren't very interesting */
4907
4908 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
4909 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
4910 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
4911 lkb->lkb_id,
4912 lkb->lkb_remid,
4913 lkb->lkb_wait_type,
4914 lkb->lkb_resource->res_nodeid,
4915 lkb->lkb_nodeid,
4916 lkb->lkb_wait_nodeid,
4917 dir_nodeid);
4918 }
4919
4920 /* all outstanding lookups, regardless of destination will be
4921 resent after recovery is done */
4922
4923 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
4924 set_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags);
4925 continue;
4926 }
4927
4928 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
4929 continue;
4930
4931 wait_type = lkb->lkb_wait_type;
4932 local_unlock_result = -DLM_EUNLOCK;
4933 local_cancel_result = -DLM_ECANCEL;
4934
4935 /* Main reply may have been received leaving a zero wait_type,
4936 but a reply for the overlapping op may not have been
4937 received. In that case we need to fake the appropriate
4938 reply for the overlap op. */
4939
4940 if (!wait_type) {
4941 if (is_overlap_cancel(lkb)) {
4942 wait_type = DLM_MSG_CANCEL;
4943 if (lkb->lkb_grmode == DLM_LOCK_IV)
4944 local_cancel_result = 0;
4945 }
4946 if (is_overlap_unlock(lkb)) {
4947 wait_type = DLM_MSG_UNLOCK;
4948 if (lkb->lkb_grmode == DLM_LOCK_IV)
4949 local_unlock_result = -ENOENT;
4950 }
4951
4952 log_debug(ls, "rwpre overlap %x %x %d %d %d",
4953 lkb->lkb_id, dlm_iflags_val(lkb), wait_type,
4954 local_cancel_result, local_unlock_result);
4955 }
4956
4957 switch (wait_type) {
4958
4959 case DLM_MSG_REQUEST:
4960 set_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags);
4961 break;
4962
4963 case DLM_MSG_CONVERT:
4964 recover_convert_waiter(ls, lkb, ms_local);
4965 break;
4966
4967 case DLM_MSG_UNLOCK:
4968 hold_lkb(lkb);
4969 memset(ms_local, 0, sizeof(struct dlm_message));
4970 ms_local->m_type = cpu_to_le32(DLM_MSG_UNLOCK_REPLY);
4971 ms_local->m_result = cpu_to_le32(to_dlm_errno(local_unlock_result));
4972 ms_local->m_header.h_nodeid = cpu_to_le32(lkb->lkb_nodeid);
4973 _receive_unlock_reply(lkb, ms_local, true);
4974 dlm_put_lkb(lkb);
4975 break;
4976
4977 case DLM_MSG_CANCEL:
4978 hold_lkb(lkb);
4979 memset(ms_local, 0, sizeof(struct dlm_message));
4980 ms_local->m_type = cpu_to_le32(DLM_MSG_CANCEL_REPLY);
4981 ms_local->m_result = cpu_to_le32(to_dlm_errno(local_cancel_result));
4982 ms_local->m_header.h_nodeid = cpu_to_le32(lkb->lkb_nodeid);
4983 _receive_cancel_reply(lkb, ms_local, true);
4984 dlm_put_lkb(lkb);
4985 break;
4986
4987 default:
4988 log_error(ls, "invalid lkb wait_type %d %d",
4989 lkb->lkb_wait_type, wait_type);
4990 }
4991 schedule();
4992 }
4993 mutex_unlock(&ls->ls_waiters_mutex);
4994 kfree(ms_local);
4995}
4996
4997static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
4998{
4999 struct dlm_lkb *lkb = NULL, *iter;
5000
5001 mutex_lock(&ls->ls_waiters_mutex);
5002 list_for_each_entry(iter, &ls->ls_waiters, lkb_wait_reply) {
5003 if (test_bit(DLM_IFL_RESEND_BIT, &iter->lkb_iflags)) {
5004 hold_lkb(iter);
5005 lkb = iter;
5006 break;
5007 }
5008 }
5009 mutex_unlock(&ls->ls_waiters_mutex);
5010
5011 return lkb;
5012}
5013
5014/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5015 master or dir-node for r. Processing the lkb may result in it being placed
5016 back on waiters. */
5017
5018/* We do this after normal locking has been enabled and any saved messages
5019 (in requestqueue) have been processed. We should be confident that at
5020 this point we won't get or process a reply to any of these waiting
5021 operations. But, new ops may be coming in on the rsbs/locks here from
5022 userspace or remotely. */
5023
5024/* there may have been an overlap unlock/cancel prior to recovery or after
5025 recovery. if before, the lkb may still have a pos wait_count; if after, the
5026 overlap flag would just have been set and nothing new sent. we can be
5027 confident here than any replies to either the initial op or overlap ops
5028 prior to recovery have been received. */
5029
5030int dlm_recover_waiters_post(struct dlm_ls *ls)
5031{
5032 struct dlm_lkb *lkb;
5033 struct dlm_rsb *r;
5034 int error = 0, mstype, err, oc, ou;
5035
5036 while (1) {
5037 if (dlm_locking_stopped(ls)) {
5038 log_debug(ls, "recover_waiters_post aborted");
5039 error = -EINTR;
5040 break;
5041 }
5042
5043 lkb = find_resend_waiter(ls);
5044 if (!lkb)
5045 break;
5046
5047 r = lkb->lkb_resource;
5048 hold_rsb(r);
5049 lock_rsb(r);
5050
5051 mstype = lkb->lkb_wait_type;
5052 oc = test_and_clear_bit(DLM_IFL_OVERLAP_CANCEL_BIT,
5053 &lkb->lkb_iflags);
5054 ou = test_and_clear_bit(DLM_IFL_OVERLAP_UNLOCK_BIT,
5055 &lkb->lkb_iflags);
5056 err = 0;
5057
5058 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5059 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5060 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5061 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5062 dlm_dir_nodeid(r), oc, ou);
5063
5064 /* At this point we assume that we won't get a reply to any
5065 previous op or overlap op on this lock. First, do a big
5066 remove_from_waiters() for all previous ops. */
5067
5068 clear_bit(DLM_IFL_RESEND_BIT, &lkb->lkb_iflags);
5069 lkb->lkb_wait_type = 0;
5070 /* drop all wait_count references we still
5071 * hold a reference for this iteration.
5072 */
5073 while (!atomic_dec_and_test(&lkb->lkb_wait_count))
5074 unhold_lkb(lkb);
5075
5076 mutex_lock(&ls->ls_waiters_mutex);
5077 list_del_init(&lkb->lkb_wait_reply);
5078 mutex_unlock(&ls->ls_waiters_mutex);
5079
5080 if (oc || ou) {
5081 /* do an unlock or cancel instead of resending */
5082 switch (mstype) {
5083 case DLM_MSG_LOOKUP:
5084 case DLM_MSG_REQUEST:
5085 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5086 -DLM_ECANCEL);
5087 unhold_lkb(lkb); /* undoes create_lkb() */
5088 break;
5089 case DLM_MSG_CONVERT:
5090 if (oc) {
5091 queue_cast(r, lkb, -DLM_ECANCEL);
5092 } else {
5093 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5094 _unlock_lock(r, lkb);
5095 }
5096 break;
5097 default:
5098 err = 1;
5099 }
5100 } else {
5101 switch (mstype) {
5102 case DLM_MSG_LOOKUP:
5103 case DLM_MSG_REQUEST:
5104 _request_lock(r, lkb);
5105 if (is_master(r))
5106 confirm_master(r, 0);
5107 break;
5108 case DLM_MSG_CONVERT:
5109 _convert_lock(r, lkb);
5110 break;
5111 default:
5112 err = 1;
5113 }
5114 }
5115
5116 if (err) {
5117 log_error(ls, "waiter %x msg %d r_nodeid %d "
5118 "dir_nodeid %d overlap %d %d",
5119 lkb->lkb_id, mstype, r->res_nodeid,
5120 dlm_dir_nodeid(r), oc, ou);
5121 }
5122 unlock_rsb(r);
5123 put_rsb(r);
5124 dlm_put_lkb(lkb);
5125 }
5126
5127 return error;
5128}
5129
5130static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5131 struct list_head *list)
5132{
5133 struct dlm_lkb *lkb, *safe;
5134
5135 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5136 if (!is_master_copy(lkb))
5137 continue;
5138
5139 /* don't purge lkbs we've added in recover_master_copy for
5140 the current recovery seq */
5141
5142 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5143 continue;
5144
5145 del_lkb(r, lkb);
5146
5147 /* this put should free the lkb */
5148 if (!dlm_put_lkb(lkb))
5149 log_error(ls, "purged mstcpy lkb not released");
5150 }
5151}
5152
5153void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
5154{
5155 struct dlm_ls *ls = r->res_ls;
5156
5157 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5158 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5159 purge_mstcpy_list(ls, r, &r->res_waitqueue);
5160}
5161
5162static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5163 struct list_head *list,
5164 int nodeid_gone, unsigned int *count)
5165{
5166 struct dlm_lkb *lkb, *safe;
5167
5168 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5169 if (!is_master_copy(lkb))
5170 continue;
5171
5172 if ((lkb->lkb_nodeid == nodeid_gone) ||
5173 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5174
5175 /* tell recover_lvb to invalidate the lvb
5176 because a node holding EX/PW failed */
5177 if ((lkb->lkb_exflags & DLM_LKF_VALBLK) &&
5178 (lkb->lkb_grmode >= DLM_LOCK_PW)) {
5179 rsb_set_flag(r, RSB_RECOVER_LVB_INVAL);
5180 }
5181
5182 del_lkb(r, lkb);
5183
5184 /* this put should free the lkb */
5185 if (!dlm_put_lkb(lkb))
5186 log_error(ls, "purged dead lkb not released");
5187
5188 rsb_set_flag(r, RSB_RECOVER_GRANT);
5189
5190 (*count)++;
5191 }
5192 }
5193}
5194
5195/* Get rid of locks held by nodes that are gone. */
5196
5197void dlm_recover_purge(struct dlm_ls *ls)
5198{
5199 struct dlm_rsb *r;
5200 struct dlm_member *memb;
5201 int nodes_count = 0;
5202 int nodeid_gone = 0;
5203 unsigned int lkb_count = 0;
5204
5205 /* cache one removed nodeid to optimize the common
5206 case of a single node removed */
5207
5208 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5209 nodes_count++;
5210 nodeid_gone = memb->nodeid;
5211 }
5212
5213 if (!nodes_count)
5214 return;
5215
5216 down_write(&ls->ls_root_sem);
5217 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5218 hold_rsb(r);
5219 lock_rsb(r);
5220 if (is_master(r)) {
5221 purge_dead_list(ls, r, &r->res_grantqueue,
5222 nodeid_gone, &lkb_count);
5223 purge_dead_list(ls, r, &r->res_convertqueue,
5224 nodeid_gone, &lkb_count);
5225 purge_dead_list(ls, r, &r->res_waitqueue,
5226 nodeid_gone, &lkb_count);
5227 }
5228 unlock_rsb(r);
5229 unhold_rsb(r);
5230 cond_resched();
5231 }
5232 up_write(&ls->ls_root_sem);
5233
5234 if (lkb_count)
5235 log_rinfo(ls, "dlm_recover_purge %u locks for %u nodes",
5236 lkb_count, nodes_count);
5237}
5238
5239static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
5240{
5241 struct rb_node *n;
5242 struct dlm_rsb *r;
5243
5244 spin_lock(&ls->ls_rsbtbl[bucket].lock);
5245 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5246 r = rb_entry(n, struct dlm_rsb, res_hashnode);
5247
5248 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5249 continue;
5250 if (!is_master(r)) {
5251 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5252 continue;
5253 }
5254 hold_rsb(r);
5255 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5256 return r;
5257 }
5258 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5259 return NULL;
5260}
5261
5262/*
5263 * Attempt to grant locks on resources that we are the master of.
5264 * Locks may have become grantable during recovery because locks
5265 * from departed nodes have been purged (or not rebuilt), allowing
5266 * previously blocked locks to now be granted. The subset of rsb's
5267 * we are interested in are those with lkb's on either the convert or
5268 * waiting queues.
5269 *
5270 * Simplest would be to go through each master rsb and check for non-empty
5271 * convert or waiting queues, and attempt to grant on those rsbs.
5272 * Checking the queues requires lock_rsb, though, for which we'd need
5273 * to release the rsbtbl lock. This would make iterating through all
5274 * rsb's very inefficient. So, we rely on earlier recovery routines
5275 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5276 * locks for.
5277 */
5278
5279void dlm_recover_grant(struct dlm_ls *ls)
5280{
5281 struct dlm_rsb *r;
5282 int bucket = 0;
5283 unsigned int count = 0;
5284 unsigned int rsb_count = 0;
5285 unsigned int lkb_count = 0;
5286
5287 while (1) {
5288 r = find_grant_rsb(ls, bucket);
5289 if (!r) {
5290 if (bucket == ls->ls_rsbtbl_size - 1)
5291 break;
5292 bucket++;
5293 continue;
5294 }
5295 rsb_count++;
5296 count = 0;
5297 lock_rsb(r);
5298 /* the RECOVER_GRANT flag is checked in the grant path */
5299 grant_pending_locks(r, &count);
5300 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5301 lkb_count += count;
5302 confirm_master(r, 0);
5303 unlock_rsb(r);
5304 put_rsb(r);
5305 cond_resched();
5306 }
5307
5308 if (lkb_count)
5309 log_rinfo(ls, "dlm_recover_grant %u locks on %u resources",
5310 lkb_count, rsb_count);
5311}
5312
5313static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5314 uint32_t remid)
5315{
5316 struct dlm_lkb *lkb;
5317
5318 list_for_each_entry(lkb, head, lkb_statequeue) {
5319 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5320 return lkb;
5321 }
5322 return NULL;
5323}
5324
5325static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5326 uint32_t remid)
5327{
5328 struct dlm_lkb *lkb;
5329
5330 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5331 if (lkb)
5332 return lkb;
5333 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5334 if (lkb)
5335 return lkb;
5336 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5337 if (lkb)
5338 return lkb;
5339 return NULL;
5340}
5341
5342/* needs at least dlm_rcom + rcom_lock */
5343static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5344 struct dlm_rsb *r, const struct dlm_rcom *rc)
5345{
5346 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5347
5348 lkb->lkb_nodeid = le32_to_cpu(rc->rc_header.h_nodeid);
5349 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5350 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5351 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5352 dlm_set_dflags_val(lkb, le32_to_cpu(rl->rl_flags));
5353 set_bit(DLM_IFL_MSTCPY_BIT, &lkb->lkb_iflags);
5354 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
5355 lkb->lkb_rqmode = rl->rl_rqmode;
5356 lkb->lkb_grmode = rl->rl_grmode;
5357 /* don't set lkb_status because add_lkb wants to itself */
5358
5359 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5360 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
5361
5362 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
5363 int lvblen = le16_to_cpu(rc->rc_header.h_length) -
5364 sizeof(struct dlm_rcom) - sizeof(struct rcom_lock);
5365 if (lvblen > ls->ls_lvblen)
5366 return -EINVAL;
5367 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
5368 if (!lkb->lkb_lvbptr)
5369 return -ENOMEM;
5370 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5371 }
5372
5373 /* Conversions between PR and CW (middle modes) need special handling.
5374 The real granted mode of these converting locks cannot be determined
5375 until all locks have been rebuilt on the rsb (recover_conversion) */
5376
5377 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5378 middle_conversion(lkb)) {
5379 rl->rl_status = DLM_LKSTS_CONVERT;
5380 lkb->lkb_grmode = DLM_LOCK_IV;
5381 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5382 }
5383
5384 return 0;
5385}
5386
5387/* This lkb may have been recovered in a previous aborted recovery so we need
5388 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5389 If so we just send back a standard reply. If not, we create a new lkb with
5390 the given values and send back our lkid. We send back our lkid by sending
5391 back the rcom_lock struct we got but with the remid field filled in. */
5392
5393/* needs at least dlm_rcom + rcom_lock */
5394int dlm_recover_master_copy(struct dlm_ls *ls, const struct dlm_rcom *rc,
5395 __le32 *rl_remid, __le32 *rl_result)
5396{
5397 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5398 struct dlm_rsb *r;
5399 struct dlm_lkb *lkb;
5400 uint32_t remid = 0;
5401 int from_nodeid = le32_to_cpu(rc->rc_header.h_nodeid);
5402 int error;
5403
5404 /* init rl_remid with rcom lock rl_remid */
5405 *rl_remid = rl->rl_remid;
5406
5407 if (rl->rl_parent_lkid) {
5408 error = -EOPNOTSUPP;
5409 goto out;
5410 }
5411
5412 remid = le32_to_cpu(rl->rl_lkid);
5413
5414 /* In general we expect the rsb returned to be R_MASTER, but we don't
5415 have to require it. Recovery of masters on one node can overlap
5416 recovery of locks on another node, so one node can send us MSTCPY
5417 locks before we've made ourselves master of this rsb. We can still
5418 add new MSTCPY locks that we receive here without any harm; when
5419 we make ourselves master, dlm_recover_masters() won't touch the
5420 MSTCPY locks we've received early. */
5421
5422 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5423 from_nodeid, R_RECEIVE_RECOVER, &r);
5424 if (error)
5425 goto out;
5426
5427 lock_rsb(r);
5428
5429 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5430 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
5431 from_nodeid, remid);
5432 error = -EBADR;
5433 goto out_unlock;
5434 }
5435
5436 lkb = search_remid(r, from_nodeid, remid);
5437 if (lkb) {
5438 error = -EEXIST;
5439 goto out_remid;
5440 }
5441
5442 error = create_lkb(ls, &lkb);
5443 if (error)
5444 goto out_unlock;
5445
5446 error = receive_rcom_lock_args(ls, lkb, r, rc);
5447 if (error) {
5448 __put_lkb(ls, lkb);
5449 goto out_unlock;
5450 }
5451
5452 attach_lkb(r, lkb);
5453 add_lkb(r, lkb, rl->rl_status);
5454 ls->ls_recover_locks_in++;
5455
5456 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5457 rsb_set_flag(r, RSB_RECOVER_GRANT);
5458
5459 out_remid:
5460 /* this is the new value returned to the lock holder for
5461 saving in its process-copy lkb */
5462 *rl_remid = cpu_to_le32(lkb->lkb_id);
5463
5464 lkb->lkb_recover_seq = ls->ls_recover_seq;
5465
5466 out_unlock:
5467 unlock_rsb(r);
5468 put_rsb(r);
5469 out:
5470 if (error && error != -EEXIST)
5471 log_rinfo(ls, "dlm_recover_master_copy remote %d %x error %d",
5472 from_nodeid, remid, error);
5473 *rl_result = cpu_to_le32(error);
5474 return error;
5475}
5476
5477/* needs at least dlm_rcom + rcom_lock */
5478int dlm_recover_process_copy(struct dlm_ls *ls, const struct dlm_rcom *rc,
5479 uint64_t seq)
5480{
5481 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5482 struct dlm_rsb *r;
5483 struct dlm_lkb *lkb;
5484 uint32_t lkid, remid;
5485 int error, result;
5486
5487 lkid = le32_to_cpu(rl->rl_lkid);
5488 remid = le32_to_cpu(rl->rl_remid);
5489 result = le32_to_cpu(rl->rl_result);
5490
5491 error = find_lkb(ls, lkid, &lkb);
5492 if (error) {
5493 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5494 lkid, le32_to_cpu(rc->rc_header.h_nodeid), remid,
5495 result);
5496 return error;
5497 }
5498
5499 r = lkb->lkb_resource;
5500 hold_rsb(r);
5501 lock_rsb(r);
5502
5503 if (!is_process_copy(lkb)) {
5504 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5505 lkid, le32_to_cpu(rc->rc_header.h_nodeid), remid,
5506 result);
5507 dlm_dump_rsb(r);
5508 unlock_rsb(r);
5509 put_rsb(r);
5510 dlm_put_lkb(lkb);
5511 return -EINVAL;
5512 }
5513
5514 switch (result) {
5515 case -EBADR:
5516 /* There's a chance the new master received our lock before
5517 dlm_recover_master_reply(), this wouldn't happen if we did
5518 a barrier between recover_masters and recover_locks. */
5519
5520 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5521 lkid, le32_to_cpu(rc->rc_header.h_nodeid), remid,
5522 result);
5523
5524 dlm_send_rcom_lock(r, lkb, seq);
5525 goto out;
5526 case -EEXIST:
5527 case 0:
5528 lkb->lkb_remid = remid;
5529 break;
5530 default:
5531 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5532 lkid, le32_to_cpu(rc->rc_header.h_nodeid), remid,
5533 result);
5534 }
5535
5536 /* an ack for dlm_recover_locks() which waits for replies from
5537 all the locks it sends to new masters */
5538 dlm_recovered_lock(r);
5539 out:
5540 unlock_rsb(r);
5541 put_rsb(r);
5542 dlm_put_lkb(lkb);
5543
5544 return 0;
5545}
5546
5547int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5548 int mode, uint32_t flags, void *name, unsigned int namelen)
5549{
5550 struct dlm_lkb *lkb;
5551 struct dlm_args args;
5552 bool do_put = true;
5553 int error;
5554
5555 dlm_lock_recovery(ls);
5556
5557 error = create_lkb(ls, &lkb);
5558 if (error) {
5559 kfree(ua);
5560 goto out;
5561 }
5562
5563 trace_dlm_lock_start(ls, lkb, name, namelen, mode, flags);
5564
5565 if (flags & DLM_LKF_VALBLK) {
5566 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5567 if (!ua->lksb.sb_lvbptr) {
5568 kfree(ua);
5569 error = -ENOMEM;
5570 goto out_put;
5571 }
5572 }
5573 error = set_lock_args(mode, &ua->lksb, flags, namelen, fake_astfn, ua,
5574 fake_bastfn, &args);
5575 if (error) {
5576 kfree(ua->lksb.sb_lvbptr);
5577 ua->lksb.sb_lvbptr = NULL;
5578 kfree(ua);
5579 goto out_put;
5580 }
5581
5582 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
5583 When DLM_DFL_USER_BIT is set, the dlm knows that this is a userspace
5584 lock and that lkb_astparam is the dlm_user_args structure. */
5585 set_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags);
5586 error = request_lock(ls, lkb, name, namelen, &args);
5587
5588 switch (error) {
5589 case 0:
5590 break;
5591 case -EINPROGRESS:
5592 error = 0;
5593 break;
5594 case -EAGAIN:
5595 error = 0;
5596 fallthrough;
5597 default:
5598 goto out_put;
5599 }
5600
5601 /* add this new lkb to the per-process list of locks */
5602 spin_lock(&ua->proc->locks_spin);
5603 hold_lkb(lkb);
5604 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5605 spin_unlock(&ua->proc->locks_spin);
5606 do_put = false;
5607 out_put:
5608 trace_dlm_lock_end(ls, lkb, name, namelen, mode, flags, error, false);
5609 if (do_put)
5610 __put_lkb(ls, lkb);
5611 out:
5612 dlm_unlock_recovery(ls);
5613 return error;
5614}
5615
5616int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5617 int mode, uint32_t flags, uint32_t lkid, char *lvb_in)
5618{
5619 struct dlm_lkb *lkb;
5620 struct dlm_args args;
5621 struct dlm_user_args *ua;
5622 int error;
5623
5624 dlm_lock_recovery(ls);
5625
5626 error = find_lkb(ls, lkid, &lkb);
5627 if (error)
5628 goto out;
5629
5630 trace_dlm_lock_start(ls, lkb, NULL, 0, mode, flags);
5631
5632 /* user can change the params on its lock when it converts it, or
5633 add an lvb that didn't exist before */
5634
5635 ua = lkb->lkb_ua;
5636
5637 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
5638 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5639 if (!ua->lksb.sb_lvbptr) {
5640 error = -ENOMEM;
5641 goto out_put;
5642 }
5643 }
5644 if (lvb_in && ua->lksb.sb_lvbptr)
5645 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5646
5647 ua->xid = ua_tmp->xid;
5648 ua->castparam = ua_tmp->castparam;
5649 ua->castaddr = ua_tmp->castaddr;
5650 ua->bastparam = ua_tmp->bastparam;
5651 ua->bastaddr = ua_tmp->bastaddr;
5652 ua->user_lksb = ua_tmp->user_lksb;
5653
5654 error = set_lock_args(mode, &ua->lksb, flags, 0, fake_astfn, ua,
5655 fake_bastfn, &args);
5656 if (error)
5657 goto out_put;
5658
5659 error = convert_lock(ls, lkb, &args);
5660
5661 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
5662 error = 0;
5663 out_put:
5664 trace_dlm_lock_end(ls, lkb, NULL, 0, mode, flags, error, false);
5665 dlm_put_lkb(lkb);
5666 out:
5667 dlm_unlock_recovery(ls);
5668 kfree(ua_tmp);
5669 return error;
5670}
5671
5672/*
5673 * The caller asks for an orphan lock on a given resource with a given mode.
5674 * If a matching lock exists, it's moved to the owner's list of locks and
5675 * the lkid is returned.
5676 */
5677
5678int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5679 int mode, uint32_t flags, void *name, unsigned int namelen,
5680 uint32_t *lkid)
5681{
5682 struct dlm_lkb *lkb = NULL, *iter;
5683 struct dlm_user_args *ua;
5684 int found_other_mode = 0;
5685 int rv = 0;
5686
5687 mutex_lock(&ls->ls_orphans_mutex);
5688 list_for_each_entry(iter, &ls->ls_orphans, lkb_ownqueue) {
5689 if (iter->lkb_resource->res_length != namelen)
5690 continue;
5691 if (memcmp(iter->lkb_resource->res_name, name, namelen))
5692 continue;
5693 if (iter->lkb_grmode != mode) {
5694 found_other_mode = 1;
5695 continue;
5696 }
5697
5698 lkb = iter;
5699 list_del_init(&iter->lkb_ownqueue);
5700 clear_bit(DLM_DFL_ORPHAN_BIT, &iter->lkb_dflags);
5701 *lkid = iter->lkb_id;
5702 break;
5703 }
5704 mutex_unlock(&ls->ls_orphans_mutex);
5705
5706 if (!lkb && found_other_mode) {
5707 rv = -EAGAIN;
5708 goto out;
5709 }
5710
5711 if (!lkb) {
5712 rv = -ENOENT;
5713 goto out;
5714 }
5715
5716 lkb->lkb_exflags = flags;
5717 lkb->lkb_ownpid = (int) current->pid;
5718
5719 ua = lkb->lkb_ua;
5720
5721 ua->proc = ua_tmp->proc;
5722 ua->xid = ua_tmp->xid;
5723 ua->castparam = ua_tmp->castparam;
5724 ua->castaddr = ua_tmp->castaddr;
5725 ua->bastparam = ua_tmp->bastparam;
5726 ua->bastaddr = ua_tmp->bastaddr;
5727 ua->user_lksb = ua_tmp->user_lksb;
5728
5729 /*
5730 * The lkb reference from the ls_orphans list was not
5731 * removed above, and is now considered the reference
5732 * for the proc locks list.
5733 */
5734
5735 spin_lock(&ua->proc->locks_spin);
5736 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5737 spin_unlock(&ua->proc->locks_spin);
5738 out:
5739 kfree(ua_tmp);
5740 return rv;
5741}
5742
5743int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5744 uint32_t flags, uint32_t lkid, char *lvb_in)
5745{
5746 struct dlm_lkb *lkb;
5747 struct dlm_args args;
5748 struct dlm_user_args *ua;
5749 int error;
5750
5751 dlm_lock_recovery(ls);
5752
5753 error = find_lkb(ls, lkid, &lkb);
5754 if (error)
5755 goto out;
5756
5757 trace_dlm_unlock_start(ls, lkb, flags);
5758
5759 ua = lkb->lkb_ua;
5760
5761 if (lvb_in && ua->lksb.sb_lvbptr)
5762 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5763 if (ua_tmp->castparam)
5764 ua->castparam = ua_tmp->castparam;
5765 ua->user_lksb = ua_tmp->user_lksb;
5766
5767 error = set_unlock_args(flags, ua, &args);
5768 if (error)
5769 goto out_put;
5770
5771 error = unlock_lock(ls, lkb, &args);
5772
5773 if (error == -DLM_EUNLOCK)
5774 error = 0;
5775 /* from validate_unlock_args() */
5776 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5777 error = 0;
5778 if (error)
5779 goto out_put;
5780
5781 spin_lock(&ua->proc->locks_spin);
5782 /* dlm_user_add_cb() may have already taken lkb off the proc list */
5783 if (!list_empty(&lkb->lkb_ownqueue))
5784 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
5785 spin_unlock(&ua->proc->locks_spin);
5786 out_put:
5787 trace_dlm_unlock_end(ls, lkb, flags, error);
5788 dlm_put_lkb(lkb);
5789 out:
5790 dlm_unlock_recovery(ls);
5791 kfree(ua_tmp);
5792 return error;
5793}
5794
5795int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5796 uint32_t flags, uint32_t lkid)
5797{
5798 struct dlm_lkb *lkb;
5799 struct dlm_args args;
5800 struct dlm_user_args *ua;
5801 int error;
5802
5803 dlm_lock_recovery(ls);
5804
5805 error = find_lkb(ls, lkid, &lkb);
5806 if (error)
5807 goto out;
5808
5809 trace_dlm_unlock_start(ls, lkb, flags);
5810
5811 ua = lkb->lkb_ua;
5812 if (ua_tmp->castparam)
5813 ua->castparam = ua_tmp->castparam;
5814 ua->user_lksb = ua_tmp->user_lksb;
5815
5816 error = set_unlock_args(flags, ua, &args);
5817 if (error)
5818 goto out_put;
5819
5820 error = cancel_lock(ls, lkb, &args);
5821
5822 if (error == -DLM_ECANCEL)
5823 error = 0;
5824 /* from validate_unlock_args() */
5825 if (error == -EBUSY)
5826 error = 0;
5827 out_put:
5828 trace_dlm_unlock_end(ls, lkb, flags, error);
5829 dlm_put_lkb(lkb);
5830 out:
5831 dlm_unlock_recovery(ls);
5832 kfree(ua_tmp);
5833 return error;
5834}
5835
5836int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
5837{
5838 struct dlm_lkb *lkb;
5839 struct dlm_args args;
5840 struct dlm_user_args *ua;
5841 struct dlm_rsb *r;
5842 int error;
5843
5844 dlm_lock_recovery(ls);
5845
5846 error = find_lkb(ls, lkid, &lkb);
5847 if (error)
5848 goto out;
5849
5850 trace_dlm_unlock_start(ls, lkb, flags);
5851
5852 ua = lkb->lkb_ua;
5853
5854 error = set_unlock_args(flags, ua, &args);
5855 if (error)
5856 goto out_put;
5857
5858 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
5859
5860 r = lkb->lkb_resource;
5861 hold_rsb(r);
5862 lock_rsb(r);
5863
5864 error = validate_unlock_args(lkb, &args);
5865 if (error)
5866 goto out_r;
5867 set_bit(DLM_IFL_DEADLOCK_CANCEL_BIT, &lkb->lkb_iflags);
5868
5869 error = _cancel_lock(r, lkb);
5870 out_r:
5871 unlock_rsb(r);
5872 put_rsb(r);
5873
5874 if (error == -DLM_ECANCEL)
5875 error = 0;
5876 /* from validate_unlock_args() */
5877 if (error == -EBUSY)
5878 error = 0;
5879 out_put:
5880 trace_dlm_unlock_end(ls, lkb, flags, error);
5881 dlm_put_lkb(lkb);
5882 out:
5883 dlm_unlock_recovery(ls);
5884 return error;
5885}
5886
5887/* lkb's that are removed from the waiters list by revert are just left on the
5888 orphans list with the granted orphan locks, to be freed by purge */
5889
5890static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
5891{
5892 struct dlm_args args;
5893 int error;
5894
5895 hold_lkb(lkb); /* reference for the ls_orphans list */
5896 mutex_lock(&ls->ls_orphans_mutex);
5897 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
5898 mutex_unlock(&ls->ls_orphans_mutex);
5899
5900 set_unlock_args(0, lkb->lkb_ua, &args);
5901
5902 error = cancel_lock(ls, lkb, &args);
5903 if (error == -DLM_ECANCEL)
5904 error = 0;
5905 return error;
5906}
5907
5908/* The FORCEUNLOCK flag allows the unlock to go ahead even if the lkb isn't
5909 granted. Regardless of what rsb queue the lock is on, it's removed and
5910 freed. The IVVALBLK flag causes the lvb on the resource to be invalidated
5911 if our lock is PW/EX (it's ignored if our granted mode is smaller.) */
5912
5913static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
5914{
5915 struct dlm_args args;
5916 int error;
5917
5918 set_unlock_args(DLM_LKF_FORCEUNLOCK | DLM_LKF_IVVALBLK,
5919 lkb->lkb_ua, &args);
5920
5921 error = unlock_lock(ls, lkb, &args);
5922 if (error == -DLM_EUNLOCK)
5923 error = 0;
5924 return error;
5925}
5926
5927/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
5928 (which does lock_rsb) due to deadlock with receiving a message that does
5929 lock_rsb followed by dlm_user_add_cb() */
5930
5931static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
5932 struct dlm_user_proc *proc)
5933{
5934 struct dlm_lkb *lkb = NULL;
5935
5936 spin_lock(&ls->ls_clear_proc_locks);
5937 if (list_empty(&proc->locks))
5938 goto out;
5939
5940 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
5941 list_del_init(&lkb->lkb_ownqueue);
5942
5943 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
5944 set_bit(DLM_DFL_ORPHAN_BIT, &lkb->lkb_dflags);
5945 else
5946 set_bit(DLM_IFL_DEAD_BIT, &lkb->lkb_iflags);
5947 out:
5948 spin_unlock(&ls->ls_clear_proc_locks);
5949 return lkb;
5950}
5951
5952/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
5953 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
5954 which we clear here. */
5955
5956/* proc CLOSING flag is set so no more device_reads should look at proc->asts
5957 list, and no more device_writes should add lkb's to proc->locks list; so we
5958 shouldn't need to take asts_spin or locks_spin here. this assumes that
5959 device reads/writes/closes are serialized -- FIXME: we may need to serialize
5960 them ourself. */
5961
5962void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
5963{
5964 struct dlm_lkb *lkb, *safe;
5965
5966 dlm_lock_recovery(ls);
5967
5968 while (1) {
5969 lkb = del_proc_lock(ls, proc);
5970 if (!lkb)
5971 break;
5972 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
5973 orphan_proc_lock(ls, lkb);
5974 else
5975 unlock_proc_lock(ls, lkb);
5976
5977 /* this removes the reference for the proc->locks list
5978 added by dlm_user_request, it may result in the lkb
5979 being freed */
5980
5981 dlm_put_lkb(lkb);
5982 }
5983
5984 spin_lock(&ls->ls_clear_proc_locks);
5985
5986 /* in-progress unlocks */
5987 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
5988 list_del_init(&lkb->lkb_ownqueue);
5989 set_bit(DLM_IFL_DEAD_BIT, &lkb->lkb_iflags);
5990 dlm_put_lkb(lkb);
5991 }
5992
5993 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
5994 dlm_purge_lkb_callbacks(lkb);
5995 list_del_init(&lkb->lkb_cb_list);
5996 dlm_put_lkb(lkb);
5997 }
5998
5999 spin_unlock(&ls->ls_clear_proc_locks);
6000 dlm_unlock_recovery(ls);
6001}
6002
6003static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6004{
6005 struct dlm_lkb *lkb, *safe;
6006
6007 while (1) {
6008 lkb = NULL;
6009 spin_lock(&proc->locks_spin);
6010 if (!list_empty(&proc->locks)) {
6011 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6012 lkb_ownqueue);
6013 list_del_init(&lkb->lkb_ownqueue);
6014 }
6015 spin_unlock(&proc->locks_spin);
6016
6017 if (!lkb)
6018 break;
6019
6020 set_bit(DLM_IFL_DEAD_BIT, &lkb->lkb_iflags);
6021 unlock_proc_lock(ls, lkb);
6022 dlm_put_lkb(lkb); /* ref from proc->locks list */
6023 }
6024
6025 spin_lock(&proc->locks_spin);
6026 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6027 list_del_init(&lkb->lkb_ownqueue);
6028 set_bit(DLM_IFL_DEAD_BIT, &lkb->lkb_iflags);
6029 dlm_put_lkb(lkb);
6030 }
6031 spin_unlock(&proc->locks_spin);
6032
6033 spin_lock(&proc->asts_spin);
6034 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
6035 dlm_purge_lkb_callbacks(lkb);
6036 list_del_init(&lkb->lkb_cb_list);
6037 dlm_put_lkb(lkb);
6038 }
6039 spin_unlock(&proc->asts_spin);
6040}
6041
6042/* pid of 0 means purge all orphans */
6043
6044static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6045{
6046 struct dlm_lkb *lkb, *safe;
6047
6048 mutex_lock(&ls->ls_orphans_mutex);
6049 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6050 if (pid && lkb->lkb_ownpid != pid)
6051 continue;
6052 unlock_proc_lock(ls, lkb);
6053 list_del_init(&lkb->lkb_ownqueue);
6054 dlm_put_lkb(lkb);
6055 }
6056 mutex_unlock(&ls->ls_orphans_mutex);
6057}
6058
6059static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6060{
6061 struct dlm_message *ms;
6062 struct dlm_mhandle *mh;
6063 int error;
6064
6065 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6066 DLM_MSG_PURGE, &ms, &mh, GFP_NOFS);
6067 if (error)
6068 return error;
6069 ms->m_nodeid = cpu_to_le32(nodeid);
6070 ms->m_pid = cpu_to_le32(pid);
6071
6072 return send_message(mh, ms, NULL, 0);
6073}
6074
6075int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6076 int nodeid, int pid)
6077{
6078 int error = 0;
6079
6080 if (nodeid && (nodeid != dlm_our_nodeid())) {
6081 error = send_purge(ls, nodeid, pid);
6082 } else {
6083 dlm_lock_recovery(ls);
6084 if (pid == current->pid)
6085 purge_proc_locks(ls, proc);
6086 else
6087 do_purge(ls, nodeid, pid);
6088 dlm_unlock_recovery(ls);
6089 }
6090 return error;
6091}
6092
6093/* debug functionality */
6094int dlm_debug_add_lkb(struct dlm_ls *ls, uint32_t lkb_id, char *name, int len,
6095 int lkb_nodeid, unsigned int lkb_dflags, int lkb_status)
6096{
6097 struct dlm_lksb *lksb;
6098 struct dlm_lkb *lkb;
6099 struct dlm_rsb *r;
6100 int error;
6101
6102 /* we currently can't set a valid user lock */
6103 if (lkb_dflags & BIT(DLM_DFL_USER_BIT))
6104 return -EOPNOTSUPP;
6105
6106 lksb = kzalloc(sizeof(*lksb), GFP_NOFS);
6107 if (!lksb)
6108 return -ENOMEM;
6109
6110 error = _create_lkb(ls, &lkb, lkb_id, lkb_id + 1);
6111 if (error) {
6112 kfree(lksb);
6113 return error;
6114 }
6115
6116 dlm_set_dflags_val(lkb, lkb_dflags);
6117 lkb->lkb_nodeid = lkb_nodeid;
6118 lkb->lkb_lksb = lksb;
6119 /* user specific pointer, just don't have it NULL for kernel locks */
6120 if (~lkb_dflags & BIT(DLM_DFL_USER_BIT))
6121 lkb->lkb_astparam = (void *)0xDEADBEEF;
6122
6123 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
6124 if (error) {
6125 kfree(lksb);
6126 __put_lkb(ls, lkb);
6127 return error;
6128 }
6129
6130 lock_rsb(r);
6131 attach_lkb(r, lkb);
6132 add_lkb(r, lkb, lkb_status);
6133 unlock_rsb(r);
6134 put_rsb(r);
6135
6136 return 0;
6137}
6138
6139int dlm_debug_add_lkb_to_waiters(struct dlm_ls *ls, uint32_t lkb_id,
6140 int mstype, int to_nodeid)
6141{
6142 struct dlm_lkb *lkb;
6143 int error;
6144
6145 error = find_lkb(ls, lkb_id, &lkb);
6146 if (error)
6147 return error;
6148
6149 error = add_to_waiters(lkb, mstype, to_nodeid);
6150 dlm_put_lkb(lkb);
6151 return error;
6152}
6153