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Merge branch 'linus' into x86/paravirt-spinlocks
[linux.git] / fs / dlm / lock.c
CommitLineData
e7fd4179
DT		 1/******************************************************************************
2*******************************************************************************
3**
46b43eed 4** Copyright (C) 2005-2008 Red Hat, Inc. All rights reserved.
e7fd4179
DT		 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*/
597d0cae 58#include <linux/types.h>
e7fd4179 59#include "dlm_internal.h"
597d0cae 60#include <linux/dlm_device.h>
e7fd4179
DT		 61#include "memory.h"
62#include "lowcomms.h"
63#include "requestqueue.h"
64#include "util.h"
65#include "dir.h"
66#include "member.h"
67#include "lockspace.h"
68#include "ast.h"
69#include "lock.h"
70#include "rcom.h"
71#include "recover.h"
72#include "lvb_table.h"
597d0cae 73#include "user.h"
e7fd4179
DT		 74#include "config.h"
75
76static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
77static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
78static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
82static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
83static int send_remove(struct dlm_rsb *r);
84static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
3ae1acf9 85static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
e7fd4179
DT		 86static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
87 struct dlm_message *ms);
88static int receive_extralen(struct dlm_message *ms);
8499137d 89static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
3ae1acf9 90static void del_timeout(struct dlm_lkb *lkb);
e7fd4179
DT		 91
92/*
93 * Lock compatibilty matrix - thanks Steve
94 * UN = Unlocked state. Not really a state, used as a flag
95 * PD = Padding. Used to make the matrix a nice power of two in size
96 * Other states are the same as the VMS DLM.
97 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
98 */
99
100static const int __dlm_compat_matrix[8][8] = {
101 /* UN NL CR CW PR PW EX PD */
102 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
103 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
104 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
105 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
106 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
107 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
108 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
109 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
110};
111
112/*
113 * This defines the direction of transfer of LVB data.
114 * Granted mode is the row; requested mode is the column.
115 * Usage: matrix[grmode+1][rqmode+1]
116 * 1 = LVB is returned to the caller
117 * 0 = LVB is written to the resource
118 * -1 = nothing happens to the LVB
119 */
120
121const int dlm_lvb_operations[8][8] = {
122 /* UN NL CR CW PR PW EX PD*/
123 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
124 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
125 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
126 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
127 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
128 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
129 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
130 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
131};
e7fd4179
DT		 132
133#define modes_compat(gr, rq) \
134 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
135
136int dlm_modes_compat(int mode1, int mode2)
137{
138 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
139}
140
141/*
142 * Compatibility matrix for conversions with QUECVT set.
143 * Granted mode is the row; requested mode is the column.
144 * Usage: matrix[grmode+1][rqmode+1]
145 */
146
147static const int __quecvt_compat_matrix[8][8] = {
148 /* UN NL CR CW PR PW EX PD */
149 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
150 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
151 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
152 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
153 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
154 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
155 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
156 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
157};
158
597d0cae 159void dlm_print_lkb(struct dlm_lkb *lkb)
e7fd4179
DT		 160{
161 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n"
162 " status %d rqmode %d grmode %d wait_type %d ast_type %d\n",
163 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
164 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
165 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_ast_type);
166}
167
170e19ab 168static void dlm_print_rsb(struct dlm_rsb *r)
e7fd4179
DT		 169{
170 printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n",
171 r->res_nodeid, r->res_flags, r->res_first_lkid,
172 r->res_recover_locks_count, r->res_name);
173}
174
a345da3e
DT		 175void dlm_dump_rsb(struct dlm_rsb *r)
176{
177 struct dlm_lkb *lkb;
178
179 dlm_print_rsb(r);
180
181 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
182 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
183 printk(KERN_ERR "rsb lookup list\n");
184 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
185 dlm_print_lkb(lkb);
186 printk(KERN_ERR "rsb grant queue:\n");
187 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
188 dlm_print_lkb(lkb);
189 printk(KERN_ERR "rsb convert queue:\n");
190 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
191 dlm_print_lkb(lkb);
192 printk(KERN_ERR "rsb wait queue:\n");
193 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
194 dlm_print_lkb(lkb);
195}
196
e7fd4179
DT		 197/* Threads cannot use the lockspace while it's being recovered */
198
85e86edf 199static inline void dlm_lock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 200{
201 down_read(&ls->ls_in_recovery);
202}
203
85e86edf 204void dlm_unlock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 205{
206 up_read(&ls->ls_in_recovery);
207}
208
85e86edf 209int dlm_lock_recovery_try(struct dlm_ls *ls)
e7fd4179
DT		 210{
211 return down_read_trylock(&ls->ls_in_recovery);
212}
213
214static inline int can_be_queued(struct dlm_lkb *lkb)
215{
216 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
217}
218
219static inline int force_blocking_asts(struct dlm_lkb *lkb)
220{
221 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
222}
223
224static inline int is_demoted(struct dlm_lkb *lkb)
225{
226 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
227}
228
7d3c1feb
DT		 229static inline int is_altmode(struct dlm_lkb *lkb)
230{
231 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
232}
233
234static inline int is_granted(struct dlm_lkb *lkb)
235{
236 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
237}
238
e7fd4179
DT		 239static inline int is_remote(struct dlm_rsb *r)
240{
241 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
242 return !!r->res_nodeid;
243}
244
245static inline int is_process_copy(struct dlm_lkb *lkb)
246{
247 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
248}
249
250static inline int is_master_copy(struct dlm_lkb *lkb)
251{
252 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
253 DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb););
90135925 254 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
e7fd4179
DT		 255}
256
257static inline int middle_conversion(struct dlm_lkb *lkb)
258{
259 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
260 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
90135925
DT		 261 return 1;
262 return 0;
e7fd4179
DT		 263}
264
265static inline int down_conversion(struct dlm_lkb *lkb)
266{
267 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
268}
269
ef0c2bb0
DT		 270static inline int is_overlap_unlock(struct dlm_lkb *lkb)
271{
272 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
273}
274
275static inline int is_overlap_cancel(struct dlm_lkb *lkb)
276{
277 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
278}
279
280static inline int is_overlap(struct dlm_lkb *lkb)
281{
282 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
283 DLM_IFL_OVERLAP_CANCEL));
284}
285
e7fd4179
DT		 286static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
287{
288 if (is_master_copy(lkb))
289 return;
290
3ae1acf9
DT		 291 del_timeout(lkb);
292
e7fd4179
DT		 293 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
294
3ae1acf9
DT		 295 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
296 timeout caused the cancel then return -ETIMEDOUT */
297 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
298 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
299 rv = -ETIMEDOUT;
300 }
301
8b4021fa
DT		 302 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
303 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
304 rv = -EDEADLK;
305 }
306
e7fd4179
DT		 307 lkb->lkb_lksb->sb_status = rv;
308 lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags;
309
310 dlm_add_ast(lkb, AST_COMP);
311}
312
ef0c2bb0
DT		 313static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
314{
315 queue_cast(r, lkb,
316 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
317}
318
e7fd4179
DT		 319static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
320{
321 if (is_master_copy(lkb))
322 send_bast(r, lkb, rqmode);
323 else {
324 lkb->lkb_bastmode = rqmode;
325 dlm_add_ast(lkb, AST_BAST);
326 }
327}
328
329/*
330 * Basic operations on rsb's and lkb's
331 */
332
333static struct dlm_rsb *create_rsb(struct dlm_ls *ls, char *name, int len)
334{
335 struct dlm_rsb *r;
336
52bda2b5 337 r = dlm_allocate_rsb(ls, len);
e7fd4179
DT		 338 if (!r)
339 return NULL;
340
341 r->res_ls = ls;
342 r->res_length = len;
343 memcpy(r->res_name, name, len);
90135925 344 mutex_init(&r->res_mutex);
e7fd4179
DT		 345
346 INIT_LIST_HEAD(&r->res_lookup);
347 INIT_LIST_HEAD(&r->res_grantqueue);
348 INIT_LIST_HEAD(&r->res_convertqueue);
349 INIT_LIST_HEAD(&r->res_waitqueue);
350 INIT_LIST_HEAD(&r->res_root_list);
351 INIT_LIST_HEAD(&r->res_recover_list);
352
353 return r;
354}
355
356static int search_rsb_list(struct list_head *head, char *name, int len,
357 unsigned int flags, struct dlm_rsb **r_ret)
358{
359 struct dlm_rsb *r;
360 int error = 0;
361
362 list_for_each_entry(r, head, res_hashchain) {
363 if (len == r->res_length && !memcmp(name, r->res_name, len))
364 goto found;
365 }
597d0cae 366 return -EBADR;
e7fd4179
DT		 367
368 found:
369 if (r->res_nodeid && (flags & R_MASTER))
370 error = -ENOTBLK;
371 *r_ret = r;
372 return error;
373}
374
375static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b,
376 unsigned int flags, struct dlm_rsb **r_ret)
377{
378 struct dlm_rsb *r;
379 int error;
380
381 error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r);
382 if (!error) {
383 kref_get(&r->res_ref);
384 goto out;
385 }
386 error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
387 if (error)
388 goto out;
389
390 list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list);
391
392 if (dlm_no_directory(ls))
393 goto out;
394
395 if (r->res_nodeid == -1) {
396 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
397 r->res_first_lkid = 0;
398 } else if (r->res_nodeid > 0) {
399 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
400 r->res_first_lkid = 0;
401 } else {
402 DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r););
403 DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),);
404 }
405 out:
406 *r_ret = r;
407 return error;
408}
409
410static int search_rsb(struct dlm_ls *ls, char *name, int len, int b,
411 unsigned int flags, struct dlm_rsb **r_ret)
412{
413 int error;
414 write_lock(&ls->ls_rsbtbl[b].lock);
415 error = _search_rsb(ls, name, len, b, flags, r_ret);
416 write_unlock(&ls->ls_rsbtbl[b].lock);
417 return error;
418}
419
420/*
421 * Find rsb in rsbtbl and potentially create/add one
422 *
423 * Delaying the release of rsb's has a similar benefit to applications keeping
424 * NL locks on an rsb, but without the guarantee that the cached master value
425 * will still be valid when the rsb is reused. Apps aren't always smart enough
426 * to keep NL locks on an rsb that they may lock again shortly; this can lead
427 * to excessive master lookups and removals if we don't delay the release.
428 *
429 * Searching for an rsb means looking through both the normal list and toss
430 * list. When found on the toss list the rsb is moved to the normal list with
431 * ref count of 1; when found on normal list the ref count is incremented.
432 */
433
434static int find_rsb(struct dlm_ls *ls, char *name, int namelen,
435 unsigned int flags, struct dlm_rsb **r_ret)
436{
437 struct dlm_rsb *r, *tmp;
438 uint32_t hash, bucket;
ef58bcca
AV		 439 int error = -EINVAL;
440
441 if (namelen > DLM_RESNAME_MAXLEN)
442 goto out;
e7fd4179
DT		 443
444 if (dlm_no_directory(ls))
445 flags |= R_CREATE;
446
ef58bcca 447 error = 0;
e7fd4179
DT		 448 hash = jhash(name, namelen, 0);
449 bucket = hash & (ls->ls_rsbtbl_size - 1);
450
451 error = search_rsb(ls, name, namelen, bucket, flags, &r);
452 if (!error)
453 goto out;
454
597d0cae 455 if (error == -EBADR && !(flags & R_CREATE))
e7fd4179
DT		 456 goto out;
457
458 /* the rsb was found but wasn't a master copy */
459 if (error == -ENOTBLK)
460 goto out;
461
462 error = -ENOMEM;
463 r = create_rsb(ls, name, namelen);
464 if (!r)
465 goto out;
466
467 r->res_hash = hash;
468 r->res_bucket = bucket;
469 r->res_nodeid = -1;
470 kref_init(&r->res_ref);
471
472 /* With no directory, the master can be set immediately */
473 if (dlm_no_directory(ls)) {
474 int nodeid = dlm_dir_nodeid(r);
475 if (nodeid == dlm_our_nodeid())
476 nodeid = 0;
477 r->res_nodeid = nodeid;
478 }
479
480 write_lock(&ls->ls_rsbtbl[bucket].lock);
481 error = _search_rsb(ls, name, namelen, bucket, 0, &tmp);
482 if (!error) {
483 write_unlock(&ls->ls_rsbtbl[bucket].lock);
52bda2b5 484 dlm_free_rsb(r);
e7fd4179
DT		 485 r = tmp;
486 goto out;
487 }
488 list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list);
489 write_unlock(&ls->ls_rsbtbl[bucket].lock);
490 error = 0;
491 out:
492 *r_ret = r;
493 return error;
494}
495
e7fd4179
DT		 496/* This is only called to add a reference when the code already holds
497 a valid reference to the rsb, so there's no need for locking. */
498
499static inline void hold_rsb(struct dlm_rsb *r)
500{
501 kref_get(&r->res_ref);
502}
503
504void dlm_hold_rsb(struct dlm_rsb *r)
505{
506 hold_rsb(r);
507}
508
509static void toss_rsb(struct kref *kref)
510{
511 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
512 struct dlm_ls *ls = r->res_ls;
513
514 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
515 kref_init(&r->res_ref);
516 list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss);
517 r->res_toss_time = jiffies;
518 if (r->res_lvbptr) {
52bda2b5 519 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 520 r->res_lvbptr = NULL;
521 }
522}
523
524/* When all references to the rsb are gone it's transfered to
525 the tossed list for later disposal. */
526
527static void put_rsb(struct dlm_rsb *r)
528{
529 struct dlm_ls *ls = r->res_ls;
530 uint32_t bucket = r->res_bucket;
531
532 write_lock(&ls->ls_rsbtbl[bucket].lock);
533 kref_put(&r->res_ref, toss_rsb);
534 write_unlock(&ls->ls_rsbtbl[bucket].lock);
535}
536
537void dlm_put_rsb(struct dlm_rsb *r)
538{
539 put_rsb(r);
540}
541
542/* See comment for unhold_lkb */
543
544static void unhold_rsb(struct dlm_rsb *r)
545{
546 int rv;
547 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 548 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 549}
550
551static void kill_rsb(struct kref *kref)
552{
553 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
554
555 /* All work is done after the return from kref_put() so we
556 can release the write_lock before the remove and free. */
557
a345da3e
DT		 558 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
559 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
560 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
561 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
562 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
563 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 564}
565
566/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
567 The rsb must exist as long as any lkb's for it do. */
568
569static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
570{
571 hold_rsb(r);
572 lkb->lkb_resource = r;
573}
574
575static void detach_lkb(struct dlm_lkb *lkb)
576{
577 if (lkb->lkb_resource) {
578 put_rsb(lkb->lkb_resource);
579 lkb->lkb_resource = NULL;
580 }
581}
582
583static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
584{
585 struct dlm_lkb *lkb, *tmp;
586 uint32_t lkid = 0;
587 uint16_t bucket;
588
52bda2b5 589 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 590 if (!lkb)
591 return -ENOMEM;
592
593 lkb->lkb_nodeid = -1;
594 lkb->lkb_grmode = DLM_LOCK_IV;
595 kref_init(&lkb->lkb_ref);
34e22bed 596 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 597 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 598 INIT_LIST_HEAD(&lkb->lkb_time_list);
e7fd4179
DT		 599
600 get_random_bytes(&bucket, sizeof(bucket));
601 bucket &= (ls->ls_lkbtbl_size - 1);
602
603 write_lock(&ls->ls_lkbtbl[bucket].lock);
604
605 /* counter can roll over so we must verify lkid is not in use */
606
607 while (lkid == 0) {
ce03f12b 608 lkid = (bucket << 16) | ls->ls_lkbtbl[bucket].counter++;
e7fd4179
DT		 609
610 list_for_each_entry(tmp, &ls->ls_lkbtbl[bucket].list,
611 lkb_idtbl_list) {
612 if (tmp->lkb_id != lkid)
613 continue;
614 lkid = 0;
615 break;
616 }
617 }
618
619 lkb->lkb_id = lkid;
620 list_add(&lkb->lkb_idtbl_list, &ls->ls_lkbtbl[bucket].list);
621 write_unlock(&ls->ls_lkbtbl[bucket].lock);
622
623 *lkb_ret = lkb;
624 return 0;
625}
626
627static struct dlm_lkb *__find_lkb(struct dlm_ls *ls, uint32_t lkid)
628{
e7fd4179 629 struct dlm_lkb *lkb;
ce03f12b 630 uint16_t bucket = (lkid >> 16);
e7fd4179
DT		 631
632 list_for_each_entry(lkb, &ls->ls_lkbtbl[bucket].list, lkb_idtbl_list) {
633 if (lkb->lkb_id == lkid)
634 return lkb;
635 }
636 return NULL;
637}
638
639static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
640{
641 struct dlm_lkb *lkb;
ce03f12b 642 uint16_t bucket = (lkid >> 16);
e7fd4179
DT		 643
644 if (bucket >= ls->ls_lkbtbl_size)
645 return -EBADSLT;
646
647 read_lock(&ls->ls_lkbtbl[bucket].lock);
648 lkb = __find_lkb(ls, lkid);
649 if (lkb)
650 kref_get(&lkb->lkb_ref);
651 read_unlock(&ls->ls_lkbtbl[bucket].lock);
652
653 *lkb_ret = lkb;
654 return lkb ? 0 : -ENOENT;
655}
656
657static void kill_lkb(struct kref *kref)
658{
659 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
660
661 /* All work is done after the return from kref_put() so we
662 can release the write_lock before the detach_lkb */
663
664 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
665}
666
b3f58d8f
DT		 667/* __put_lkb() is used when an lkb may not have an rsb attached to
668 it so we need to provide the lockspace explicitly */
669
670static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 671{
ce03f12b 672 uint16_t bucket = (lkb->lkb_id >> 16);
e7fd4179
DT		 673
674 write_lock(&ls->ls_lkbtbl[bucket].lock);
675 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
676 list_del(&lkb->lkb_idtbl_list);
677 write_unlock(&ls->ls_lkbtbl[bucket].lock);
678
679 detach_lkb(lkb);
680
681 /* for local/process lkbs, lvbptr points to caller's lksb */
682 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 683 dlm_free_lvb(lkb->lkb_lvbptr);
684 dlm_free_lkb(lkb);
e7fd4179
DT		 685 return 1;
686 } else {
687 write_unlock(&ls->ls_lkbtbl[bucket].lock);
688 return 0;
689 }
690}
691
692int dlm_put_lkb(struct dlm_lkb *lkb)
693{
b3f58d8f
DT		 694 struct dlm_ls *ls;
695
696 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
697 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
698
699 ls = lkb->lkb_resource->res_ls;
700 return __put_lkb(ls, lkb);
e7fd4179
DT		 701}
702
703/* This is only called to add a reference when the code already holds
704 a valid reference to the lkb, so there's no need for locking. */
705
706static inline void hold_lkb(struct dlm_lkb *lkb)
707{
708 kref_get(&lkb->lkb_ref);
709}
710
711/* This is called when we need to remove a reference and are certain
712 it's not the last ref. e.g. del_lkb is always called between a
713 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
714 put_lkb would work fine, but would involve unnecessary locking */
715
716static inline void unhold_lkb(struct dlm_lkb *lkb)
717{
718 int rv;
719 rv = kref_put(&lkb->lkb_ref, kill_lkb);
720 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
721}
722
723static void lkb_add_ordered(struct list_head *new, struct list_head *head,
724 int mode)
725{
726 struct dlm_lkb *lkb = NULL;
727
728 list_for_each_entry(lkb, head, lkb_statequeue)
729 if (lkb->lkb_rqmode < mode)
730 break;
731
732 if (!lkb)
733 list_add_tail(new, head);
734 else
735 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
736}
737
738/* add/remove lkb to rsb's grant/convert/wait queue */
739
740static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
741{
742 kref_get(&lkb->lkb_ref);
743
744 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
745
746 lkb->lkb_status = status;
747
748 switch (status) {
749 case DLM_LKSTS_WAITING:
750 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
751 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
752 else
753 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
754 break;
755 case DLM_LKSTS_GRANTED:
756 /* convention says granted locks kept in order of grmode */
757 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
758 lkb->lkb_grmode);
759 break;
760 case DLM_LKSTS_CONVERT:
761 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
762 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
763 else
764 list_add_tail(&lkb->lkb_statequeue,
765 &r->res_convertqueue);
766 break;
767 default:
768 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
769 }
770}
771
772static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
773{
774 lkb->lkb_status = 0;
775 list_del(&lkb->lkb_statequeue);
776 unhold_lkb(lkb);
777}
778
779static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
780{
781 hold_lkb(lkb);
782 del_lkb(r, lkb);
783 add_lkb(r, lkb, sts);
784 unhold_lkb(lkb);
785}
786
ef0c2bb0
DT		 787static int msg_reply_type(int mstype)
788{
789 switch (mstype) {
790 case DLM_MSG_REQUEST:
791 return DLM_MSG_REQUEST_REPLY;
792 case DLM_MSG_CONVERT:
793 return DLM_MSG_CONVERT_REPLY;
794 case DLM_MSG_UNLOCK:
795 return DLM_MSG_UNLOCK_REPLY;
796 case DLM_MSG_CANCEL:
797 return DLM_MSG_CANCEL_REPLY;
798 case DLM_MSG_LOOKUP:
799 return DLM_MSG_LOOKUP_REPLY;
800 }
801 return -1;
802}
803
e7fd4179
DT		 804/* add/remove lkb from global waiters list of lkb's waiting for
805 a reply from a remote node */
806
ef0c2bb0 807static int add_to_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 808{
809 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 810 int error = 0;
e7fd4179 811
90135925 812 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 813
814 if (is_overlap_unlock(lkb) ||
815 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
816 error = -EINVAL;
817 goto out;
818 }
819
820 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
821 switch (mstype) {
822 case DLM_MSG_UNLOCK:
823 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
824 break;
825 case DLM_MSG_CANCEL:
826 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
827 break;
828 default:
829 error = -EBUSY;
830 goto out;
831 }
832 lkb->lkb_wait_count++;
833 hold_lkb(lkb);
834
835 log_debug(ls, "add overlap %x cur %d new %d count %d flags %x",
836 lkb->lkb_id, lkb->lkb_wait_type, mstype,
837 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 838 goto out;
839 }
ef0c2bb0
DT		 840
841 DLM_ASSERT(!lkb->lkb_wait_count,
842 dlm_print_lkb(lkb);
843 printk("wait_count %d\n", lkb->lkb_wait_count););
844
845 lkb->lkb_wait_count++;
e7fd4179 846 lkb->lkb_wait_type = mstype;
ef0c2bb0 847 hold_lkb(lkb);
e7fd4179
DT		 848 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
849 out:
ef0c2bb0
DT		 850 if (error)
851 log_error(ls, "add_to_waiters %x error %d flags %x %d %d %s",
852 lkb->lkb_id, error, lkb->lkb_flags, mstype,
853 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 854 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 855 return error;
e7fd4179
DT		 856}
857
b790c3b7
DT		 858/* We clear the RESEND flag because we might be taking an lkb off the waiters
859 list as part of process_requestqueue (e.g. a lookup that has an optimized
860 request reply on the requestqueue) between dlm_recover_waiters_pre() which
861 set RESEND and dlm_recover_waiters_post() */
862
ef0c2bb0 863static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179 864{
ef0c2bb0
DT		 865 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
866 int overlap_done = 0;
e7fd4179 867
ef0c2bb0
DT		 868 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
869 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
870 overlap_done = 1;
871 goto out_del;
e7fd4179 872 }
ef0c2bb0
DT		 873
874 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
875 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
876 overlap_done = 1;
877 goto out_del;
878 }
879
880 /* N.B. type of reply may not always correspond to type of original
881 msg due to lookup->request optimization, verify others? */
882
883 if (lkb->lkb_wait_type) {
884 lkb->lkb_wait_type = 0;
885 goto out_del;
886 }
887
888 log_error(ls, "remove_from_waiters lkid %x flags %x types %d %d",
889 lkb->lkb_id, lkb->lkb_flags, mstype, lkb->lkb_wait_type);
890 return -1;
891
892 out_del:
893 /* the force-unlock/cancel has completed and we haven't recvd a reply
894 to the op that was in progress prior to the unlock/cancel; we
895 give up on any reply to the earlier op. FIXME: not sure when/how
896 this would happen */
897
898 if (overlap_done && lkb->lkb_wait_type) {
899 log_error(ls, "remove_from_waiters %x reply %d give up on %d",
900 lkb->lkb_id, mstype, lkb->lkb_wait_type);
901 lkb->lkb_wait_count--;
902 lkb->lkb_wait_type = 0;
903 }
904
905 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
906
b790c3b7 907 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 908 lkb->lkb_wait_count--;
909 if (!lkb->lkb_wait_count)
910 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 911 unhold_lkb(lkb);
ef0c2bb0 912 return 0;
e7fd4179
DT		 913}
914
ef0c2bb0 915static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 916{
917 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
918 int error;
919
90135925 920 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0 921 error = _remove_from_waiters(lkb, mstype);
90135925 922 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 923 return error;
924}
925
ef0c2bb0
DT		 926/* Handles situations where we might be processing a "fake" or "stub" reply in
927 which we can't try to take waiters_mutex again. */
928
929static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
930{
931 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
932 int error;
933
934 if (ms != &ls->ls_stub_ms)
935 mutex_lock(&ls->ls_waiters_mutex);
936 error = _remove_from_waiters(lkb, ms->m_type);
937 if (ms != &ls->ls_stub_ms)
938 mutex_unlock(&ls->ls_waiters_mutex);
939 return error;
940}
941
e7fd4179
DT		 942static void dir_remove(struct dlm_rsb *r)
943{
944 int to_nodeid;
945
946 if (dlm_no_directory(r->res_ls))
947 return;
948
949 to_nodeid = dlm_dir_nodeid(r);
950 if (to_nodeid != dlm_our_nodeid())
951 send_remove(r);
952 else
953 dlm_dir_remove_entry(r->res_ls, to_nodeid,
954 r->res_name, r->res_length);
955}
956
957/* FIXME: shouldn't this be able to exit as soon as one non-due rsb is
958 found since they are in order of newest to oldest? */
959
960static int shrink_bucket(struct dlm_ls *ls, int b)
961{
962 struct dlm_rsb *r;
963 int count = 0, found;
964
965 for (;;) {
90135925 966 found = 0;
e7fd4179
DT		 967 write_lock(&ls->ls_rsbtbl[b].lock);
968 list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss,
969 res_hashchain) {
970 if (!time_after_eq(jiffies, r->res_toss_time +
68c817a1 971 dlm_config.ci_toss_secs * HZ))
e7fd4179 972 continue;
90135925 973 found = 1;
e7fd4179
DT		 974 break;
975 }
976
977 if (!found) {
978 write_unlock(&ls->ls_rsbtbl[b].lock);
979 break;
980 }
981
982 if (kref_put(&r->res_ref, kill_rsb)) {
983 list_del(&r->res_hashchain);
984 write_unlock(&ls->ls_rsbtbl[b].lock);
985
986 if (is_master(r))
987 dir_remove(r);
52bda2b5 988 dlm_free_rsb(r);
e7fd4179
DT		 989 count++;
990 } else {
991 write_unlock(&ls->ls_rsbtbl[b].lock);
992 log_error(ls, "tossed rsb in use %s", r->res_name);
993 }
994 }
995
996 return count;
997}
998
999void dlm_scan_rsbs(struct dlm_ls *ls)
1000{
1001 int i;
1002
e7fd4179
DT		 1003 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1004 shrink_bucket(ls, i);
85e86edf
DT		 1005 if (dlm_locking_stopped(ls))
1006 break;
e7fd4179
DT		 1007 cond_resched();
1008 }
1009}
1010
3ae1acf9
DT		 1011static void add_timeout(struct dlm_lkb *lkb)
1012{
1013 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1014
84d8cd69
DT		 1015 if (is_master_copy(lkb)) {
1016 lkb->lkb_timestamp = jiffies;
3ae1acf9 1017 return;
84d8cd69 1018 }
3ae1acf9
DT		 1019
1020 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1021 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1022 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1023 goto add_it;
1024 }
84d8cd69
DT		 1025 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1026 goto add_it;
3ae1acf9
DT		 1027 return;
1028
1029 add_it:
1030 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1031 mutex_lock(&ls->ls_timeout_mutex);
1032 hold_lkb(lkb);
1033 lkb->lkb_timestamp = jiffies;
1034 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1035 mutex_unlock(&ls->ls_timeout_mutex);
1036}
1037
1038static void del_timeout(struct dlm_lkb *lkb)
1039{
1040 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1041
1042 mutex_lock(&ls->ls_timeout_mutex);
1043 if (!list_empty(&lkb->lkb_time_list)) {
1044 list_del_init(&lkb->lkb_time_list);
1045 unhold_lkb(lkb);
1046 }
1047 mutex_unlock(&ls->ls_timeout_mutex);
1048}
1049
1050/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1051 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1052 and then lock rsb because of lock ordering in add_timeout. We may need
1053 to specify some special timeout-related bits in the lkb that are just to
1054 be accessed under the timeout_mutex. */
1055
1056void dlm_scan_timeout(struct dlm_ls *ls)
1057{
1058 struct dlm_rsb *r;
1059 struct dlm_lkb *lkb;
1060 int do_cancel, do_warn;
1061
1062 for (;;) {
1063 if (dlm_locking_stopped(ls))
1064 break;
1065
1066 do_cancel = 0;
1067 do_warn = 0;
1068 mutex_lock(&ls->ls_timeout_mutex);
1069 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1070
1071 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
1072 time_after_eq(jiffies, lkb->lkb_timestamp +
1073 lkb->lkb_timeout_cs * HZ/100))
1074 do_cancel = 1;
1075
1076 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
1077 time_after_eq(jiffies, lkb->lkb_timestamp +
1078 dlm_config.ci_timewarn_cs * HZ/100))
1079 do_warn = 1;
1080
1081 if (!do_cancel && !do_warn)
1082 continue;
1083 hold_lkb(lkb);
1084 break;
1085 }
1086 mutex_unlock(&ls->ls_timeout_mutex);
1087
1088 if (!do_cancel && !do_warn)
1089 break;
1090
1091 r = lkb->lkb_resource;
1092 hold_rsb(r);
1093 lock_rsb(r);
1094
1095 if (do_warn) {
1096 /* clear flag so we only warn once */
1097 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1098 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1099 del_timeout(lkb);
1100 dlm_timeout_warn(lkb);
1101 }
1102
1103 if (do_cancel) {
b3cab7b9 1104 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1105 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1106 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1107 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1108 del_timeout(lkb);
1109 _cancel_lock(r, lkb);
1110 }
1111
1112 unlock_rsb(r);
1113 unhold_rsb(r);
1114 dlm_put_lkb(lkb);
1115 }
1116}
1117
1118/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1119 dlm_recoverd before checking/setting ls_recover_begin. */
1120
1121void dlm_adjust_timeouts(struct dlm_ls *ls)
1122{
1123 struct dlm_lkb *lkb;
1124 long adj = jiffies - ls->ls_recover_begin;
1125
1126 ls->ls_recover_begin = 0;
1127 mutex_lock(&ls->ls_timeout_mutex);
1128 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
1129 lkb->lkb_timestamp += adj;
1130 mutex_unlock(&ls->ls_timeout_mutex);
1131}
1132
e7fd4179
DT		 1133/* lkb is master or local copy */
1134
1135static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1136{
1137 int b, len = r->res_ls->ls_lvblen;
1138
1139 /* b=1 lvb returned to caller
1140 b=0 lvb written to rsb or invalidated
1141 b=-1 do nothing */
1142
1143 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1144
1145 if (b == 1) {
1146 if (!lkb->lkb_lvbptr)
1147 return;
1148
1149 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1150 return;
1151
1152 if (!r->res_lvbptr)
1153 return;
1154
1155 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1156 lkb->lkb_lvbseq = r->res_lvbseq;
1157
1158 } else if (b == 0) {
1159 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1160 rsb_set_flag(r, RSB_VALNOTVALID);
1161 return;
1162 }
1163
1164 if (!lkb->lkb_lvbptr)
1165 return;
1166
1167 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1168 return;
1169
1170 if (!r->res_lvbptr)
52bda2b5 1171 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1172
1173 if (!r->res_lvbptr)
1174 return;
1175
1176 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1177 r->res_lvbseq++;
1178 lkb->lkb_lvbseq = r->res_lvbseq;
1179 rsb_clear_flag(r, RSB_VALNOTVALID);
1180 }
1181
1182 if (rsb_flag(r, RSB_VALNOTVALID))
1183 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1184}
1185
1186static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1187{
1188 if (lkb->lkb_grmode < DLM_LOCK_PW)
1189 return;
1190
1191 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1192 rsb_set_flag(r, RSB_VALNOTVALID);
1193 return;
1194 }
1195
1196 if (!lkb->lkb_lvbptr)
1197 return;
1198
1199 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1200 return;
1201
1202 if (!r->res_lvbptr)
52bda2b5 1203 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1204
1205 if (!r->res_lvbptr)
1206 return;
1207
1208 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
1209 r->res_lvbseq++;
1210 rsb_clear_flag(r, RSB_VALNOTVALID);
1211}
1212
1213/* lkb is process copy (pc) */
1214
1215static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1216 struct dlm_message *ms)
1217{
1218 int b;
1219
1220 if (!lkb->lkb_lvbptr)
1221 return;
1222
1223 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1224 return;
1225
597d0cae 1226 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 1227 if (b == 1) {
1228 int len = receive_extralen(ms);
a9cc9159
AV		 1229 if (len > DLM_RESNAME_MAXLEN)
1230 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 1231 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
1232 lkb->lkb_lvbseq = ms->m_lvbseq;
1233 }
1234}
1235
1236/* Manipulate lkb's on rsb's convert/granted/waiting queues
1237 remove_lock -- used for unlock, removes lkb from granted
1238 revert_lock -- used for cancel, moves lkb from convert to granted
1239 grant_lock -- used for request and convert, adds lkb to granted or
1240 moves lkb from convert or waiting to granted
1241
1242 Each of these is used for master or local copy lkb's. There is
1243 also a _pc() variation used to make the corresponding change on
1244 a process copy (pc) lkb. */
1245
1246static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1247{
1248 del_lkb(r, lkb);
1249 lkb->lkb_grmode = DLM_LOCK_IV;
1250 /* this unhold undoes the original ref from create_lkb()
1251 so this leads to the lkb being freed */
1252 unhold_lkb(lkb);
1253}
1254
1255static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1256{
1257 set_lvb_unlock(r, lkb);
1258 _remove_lock(r, lkb);
1259}
1260
1261static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1262{
1263 _remove_lock(r, lkb);
1264}
1265
ef0c2bb0
DT		 1266/* returns: 0 did nothing
1267 1 moved lock to granted
1268 -1 removed lock */
1269
1270static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1271{
ef0c2bb0
DT		 1272 int rv = 0;
1273
e7fd4179
DT		 1274 lkb->lkb_rqmode = DLM_LOCK_IV;
1275
1276 switch (lkb->lkb_status) {
597d0cae
DT		 1277 case DLM_LKSTS_GRANTED:
1278 break;
e7fd4179
DT		 1279 case DLM_LKSTS_CONVERT:
1280 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 1281 rv = 1;
e7fd4179
DT		 1282 break;
1283 case DLM_LKSTS_WAITING:
1284 del_lkb(r, lkb);
1285 lkb->lkb_grmode = DLM_LOCK_IV;
1286 /* this unhold undoes the original ref from create_lkb()
1287 so this leads to the lkb being freed */
1288 unhold_lkb(lkb);
ef0c2bb0 1289 rv = -1;
e7fd4179
DT		 1290 break;
1291 default:
1292 log_print("invalid status for revert %d", lkb->lkb_status);
1293 }
ef0c2bb0 1294 return rv;
e7fd4179
DT		 1295}
1296
ef0c2bb0 1297static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1298{
ef0c2bb0 1299 return revert_lock(r, lkb);
e7fd4179
DT		 1300}
1301
1302static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1303{
1304 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
1305 lkb->lkb_grmode = lkb->lkb_rqmode;
1306 if (lkb->lkb_status)
1307 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1308 else
1309 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
1310 }
1311
1312 lkb->lkb_rqmode = DLM_LOCK_IV;
e7fd4179
DT		 1313}
1314
1315static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1316{
1317 set_lvb_lock(r, lkb);
1318 _grant_lock(r, lkb);
1319 lkb->lkb_highbast = 0;
1320}
1321
1322static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1323 struct dlm_message *ms)
1324{
1325 set_lvb_lock_pc(r, lkb, ms);
1326 _grant_lock(r, lkb);
1327}
1328
1329/* called by grant_pending_locks() which means an async grant message must
1330 be sent to the requesting node in addition to granting the lock if the
1331 lkb belongs to a remote node. */
1332
1333static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
1334{
1335 grant_lock(r, lkb);
1336 if (is_master_copy(lkb))
1337 send_grant(r, lkb);
1338 else
1339 queue_cast(r, lkb, 0);
1340}
1341
7d3c1feb
DT		 1342/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
1343 change the granted/requested modes. We're munging things accordingly in
1344 the process copy.
1345 CONVDEADLK: our grmode may have been forced down to NL to resolve a
1346 conversion deadlock
1347 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
1348 compatible with other granted locks */
1349
1350static void munge_demoted(struct dlm_lkb *lkb, struct dlm_message *ms)
1351{
1352 if (ms->m_type != DLM_MSG_CONVERT_REPLY) {
1353 log_print("munge_demoted %x invalid reply type %d",
1354 lkb->lkb_id, ms->m_type);
1355 return;
1356 }
1357
1358 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
1359 log_print("munge_demoted %x invalid modes gr %d rq %d",
1360 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
1361 return;
1362 }
1363
1364 lkb->lkb_grmode = DLM_LOCK_NL;
1365}
1366
1367static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
1368{
1369 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
1370 ms->m_type != DLM_MSG_GRANT) {
1371 log_print("munge_altmode %x invalid reply type %d",
1372 lkb->lkb_id, ms->m_type);
1373 return;
1374 }
1375
1376 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
1377 lkb->lkb_rqmode = DLM_LOCK_PR;
1378 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
1379 lkb->lkb_rqmode = DLM_LOCK_CW;
1380 else {
1381 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
1382 dlm_print_lkb(lkb);
1383 }
1384}
1385
e7fd4179
DT		 1386static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
1387{
1388 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
1389 lkb_statequeue);
1390 if (lkb->lkb_id == first->lkb_id)
90135925 1391 return 1;
e7fd4179 1392
90135925 1393 return 0;
e7fd4179
DT		 1394}
1395
e7fd4179
DT		 1396/* Check if the given lkb conflicts with another lkb on the queue. */
1397
1398static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
1399{
1400 struct dlm_lkb *this;
1401
1402 list_for_each_entry(this, head, lkb_statequeue) {
1403 if (this == lkb)
1404 continue;
3bcd3687 1405 if (!modes_compat(this, lkb))
90135925 1406 return 1;
e7fd4179 1407 }
90135925 1408 return 0;
e7fd4179
DT		 1409}
1410
1411/*
1412 * "A conversion deadlock arises with a pair of lock requests in the converting
1413 * queue for one resource. The granted mode of each lock blocks the requested
1414 * mode of the other lock."
1415 *
c85d65e9
DT		 1416 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
1417 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 1418 *
1419 * Example:
1420 * Granted Queue: empty
1421 * Convert Queue: NL->EX (first lock)
1422 * PR->EX (second lock)
1423 *
1424 * The first lock can't be granted because of the granted mode of the second
1425 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 1426 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
1427 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
1428 * flag set and return DEMOTED in the lksb flags.
e7fd4179 1429 *
c85d65e9
DT		 1430 * Originally, this function detected conv-deadlk in a more limited scope:
1431 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
1432 * - if lkb1 was the first entry in the queue (not just earlier), and was
1433 * blocked by the granted mode of lkb2, and there was nothing on the
1434 * granted queue preventing lkb1 from being granted immediately, i.e.
1435 * lkb2 was the only thing preventing lkb1 from being granted.
1436 *
1437 * That second condition meant we'd only say there was conv-deadlk if
1438 * resolving it (by demotion) would lead to the first lock on the convert
1439 * queue being granted right away. It allowed conversion deadlocks to exist
1440 * between locks on the convert queue while they couldn't be granted anyway.
1441 *
1442 * Now, we detect and take action on conversion deadlocks immediately when
1443 * they're created, even if they may not be immediately consequential. If
1444 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
1445 * mode that would prevent lkb1's conversion from being granted, we do a
1446 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
1447 * I think this means that the lkb_is_ahead condition below should always
1448 * be zero, i.e. there will never be conv-deadlk between two locks that are
1449 * both already on the convert queue.
e7fd4179
DT		 1450 */
1451
c85d65e9 1452static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 1453{
c85d65e9
DT		 1454 struct dlm_lkb *lkb1;
1455 int lkb_is_ahead = 0;
e7fd4179 1456
c85d65e9
DT		 1457 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
1458 if (lkb1 == lkb2) {
1459 lkb_is_ahead = 1;
e7fd4179
DT		 1460 continue;
1461 }
1462
c85d65e9
DT		 1463 if (!lkb_is_ahead) {
1464 if (!modes_compat(lkb2, lkb1))
1465 return 1;
1466 } else {
1467 if (!modes_compat(lkb2, lkb1) &&
1468 !modes_compat(lkb1, lkb2))
1469 return 1;
1470 }
e7fd4179 1471 }
90135925 1472 return 0;
e7fd4179
DT		 1473}
1474
1475/*
1476 * Return 1 if the lock can be granted, 0 otherwise.
1477 * Also detect and resolve conversion deadlocks.
1478 *
1479 * lkb is the lock to be granted
1480 *
1481 * now is 1 if the function is being called in the context of the
1482 * immediate request, it is 0 if called later, after the lock has been
1483 * queued.
1484 *
1485 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
1486 */
1487
1488static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now)
1489{
1490 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
1491
1492 /*
1493 * 6-10: Version 5.4 introduced an option to address the phenomenon of
1494 * a new request for a NL mode lock being blocked.
1495 *
1496 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
1497 * request, then it would be granted. In essence, the use of this flag
1498 * tells the Lock Manager to expedite theis request by not considering
1499 * what may be in the CONVERTING or WAITING queues... As of this
1500 * writing, the EXPEDITE flag can be used only with new requests for NL
1501 * mode locks. This flag is not valid for conversion requests.
1502 *
1503 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
1504 * conversion or used with a non-NL requested mode. We also know an
1505 * EXPEDITE request is always granted immediately, so now must always
1506 * be 1. The full condition to grant an expedite request: (now &&
1507 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
1508 * therefore be shortened to just checking the flag.
1509 */
1510
1511 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 1512 return 1;
e7fd4179
DT		 1513
1514 /*
1515 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
1516 * added to the remaining conditions.
1517 */
1518
1519 if (queue_conflict(&r->res_grantqueue, lkb))
1520 goto out;
1521
1522 /*
1523 * 6-3: By default, a conversion request is immediately granted if the
1524 * requested mode is compatible with the modes of all other granted
1525 * locks
1526 */
1527
1528 if (queue_conflict(&r->res_convertqueue, lkb))
1529 goto out;
1530
1531 /*
1532 * 6-5: But the default algorithm for deciding whether to grant or
1533 * queue conversion requests does not by itself guarantee that such
1534 * requests are serviced on a "first come first serve" basis. This, in
1535 * turn, can lead to a phenomenon known as "indefinate postponement".
1536 *
1537 * 6-7: This issue is dealt with by using the optional QUECVT flag with
1538 * the system service employed to request a lock conversion. This flag
1539 * forces certain conversion requests to be queued, even if they are
1540 * compatible with the granted modes of other locks on the same
1541 * resource. Thus, the use of this flag results in conversion requests
1542 * being ordered on a "first come first servce" basis.
1543 *
1544 * DCT: This condition is all about new conversions being able to occur
1545 * "in place" while the lock remains on the granted queue (assuming
1546 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
1547 * doesn't _have_ to go onto the convert queue where it's processed in
1548 * order. The "now" variable is necessary to distinguish converts
1549 * being received and processed for the first time now, because once a
1550 * convert is moved to the conversion queue the condition below applies
1551 * requiring fifo granting.
1552 */
1553
1554 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 1555 return 1;
e7fd4179
DT		 1556
1557 /*
3bcd3687
DT		 1558 * The NOORDER flag is set to avoid the standard vms rules on grant
1559 * order.
e7fd4179
DT		 1560 */
1561
1562 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 1563 return 1;
e7fd4179
DT		 1564
1565 /*
1566 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
1567 * granted until all other conversion requests ahead of it are granted
1568 * and/or canceled.
1569 */
1570
1571 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 1572 return 1;
e7fd4179
DT		 1573
1574 /*
1575 * 6-4: By default, a new request is immediately granted only if all
1576 * three of the following conditions are satisfied when the request is
1577 * issued:
1578 * - The queue of ungranted conversion requests for the resource is
1579 * empty.
1580 * - The queue of ungranted new requests for the resource is empty.
1581 * - The mode of the new request is compatible with the most
1582 * restrictive mode of all granted locks on the resource.
1583 */
1584
1585 if (now && !conv && list_empty(&r->res_convertqueue) &&
1586 list_empty(&r->res_waitqueue))
90135925 1587 return 1;
e7fd4179
DT		 1588
1589 /*
1590 * 6-4: Once a lock request is in the queue of ungranted new requests,
1591 * it cannot be granted until the queue of ungranted conversion
1592 * requests is empty, all ungranted new requests ahead of it are
1593 * granted and/or canceled, and it is compatible with the granted mode
1594 * of the most restrictive lock granted on the resource.
1595 */
1596
1597 if (!now && !conv && list_empty(&r->res_convertqueue) &&
1598 first_in_list(lkb, &r->res_waitqueue))
90135925 1599 return 1;
e7fd4179 1600 out:
90135925 1601 return 0;
e7fd4179
DT		 1602}
1603
c85d65e9
DT		 1604static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
1605 int *err)
e7fd4179 1606{
e7fd4179
DT		 1607 int rv;
1608 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 1609 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
1610
1611 if (err)
1612 *err = 0;
e7fd4179
DT		 1613
1614 rv = _can_be_granted(r, lkb, now);
1615 if (rv)
1616 goto out;
1617
c85d65e9
DT		 1618 /*
1619 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
1620 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
1621 * cancels one of the locks.
1622 */
1623
1624 if (is_convert && can_be_queued(lkb) &&
1625 conversion_deadlock_detect(r, lkb)) {
1626 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
1627 lkb->lkb_grmode = DLM_LOCK_NL;
1628 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
1629 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1630 if (err)
1631 *err = -EDEADLK;
1632 else {
1633 log_print("can_be_granted deadlock %x now %d",
1634 lkb->lkb_id, now);
1635 dlm_dump_rsb(r);
1636 }
1637 }
e7fd4179 1638 goto out;
c85d65e9 1639 }
e7fd4179 1640
c85d65e9
DT		 1641 /*
1642 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
1643 * to grant a request in a mode other than the normal rqmode. It's a
1644 * simple way to provide a big optimization to applications that can
1645 * use them.
1646 */
1647
1648 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 1649 alt = DLM_LOCK_PR;
c85d65e9 1650 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 1651 alt = DLM_LOCK_CW;
1652
1653 if (alt) {
1654 lkb->lkb_rqmode = alt;
1655 rv = _can_be_granted(r, lkb, now);
1656 if (rv)
1657 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
1658 else
1659 lkb->lkb_rqmode = rqmode;
1660 }
1661 out:
1662 return rv;
1663}
1664
c85d65e9
DT		 1665/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
1666 for locks pending on the convert list. Once verified (watch for these
1667 log_prints), we should be able to just call _can_be_granted() and not
1668 bother with the demote/deadlk cases here (and there's no easy way to deal
1669 with a deadlk here, we'd have to generate something like grant_lock with
1670 the deadlk error.) */
1671
36509258
DT		 1672/* Returns the highest requested mode of all blocked conversions; sets
1673 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 1674
36509258 1675static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1676{
1677 struct dlm_lkb *lkb, *s;
1678 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 1679 int deadlk;
e7fd4179
DT		 1680
1681 quit = 0;
1682 restart:
1683 grant_restart = 0;
1684 demote_restart = 0;
1685 hi = DLM_LOCK_IV;
1686
1687 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
1688 demoted = is_demoted(lkb);
c85d65e9
DT		 1689 deadlk = 0;
1690
1691 if (can_be_granted(r, lkb, 0, &deadlk)) {
e7fd4179
DT		 1692 grant_lock_pending(r, lkb);
1693 grant_restart = 1;
c85d65e9 1694 continue;
e7fd4179 1695 }
c85d65e9
DT		 1696
1697 if (!demoted && is_demoted(lkb)) {
1698 log_print("WARN: pending demoted %x node %d %s",
1699 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1700 demote_restart = 1;
1701 continue;
1702 }
1703
1704 if (deadlk) {
1705 log_print("WARN: pending deadlock %x node %d %s",
1706 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1707 dlm_dump_rsb(r);
1708 continue;
1709 }
1710
1711 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 1712
1713 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
1714 *cw = 1;
e7fd4179
DT		 1715 }
1716
1717 if (grant_restart)
1718 goto restart;
1719 if (demote_restart && !quit) {
1720 quit = 1;
1721 goto restart;
1722 }
1723
1724 return max_t(int, high, hi);
1725}
1726
36509258 1727static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1728{
1729 struct dlm_lkb *lkb, *s;
1730
1731 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c85d65e9 1732 if (can_be_granted(r, lkb, 0, NULL))
e7fd4179 1733 grant_lock_pending(r, lkb);
36509258 1734 else {
e7fd4179 1735 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 1736 if (lkb->lkb_rqmode == DLM_LOCK_CW)
1737 *cw = 1;
1738 }
e7fd4179
DT		 1739 }
1740
1741 return high;
1742}
1743
36509258
DT		 1744/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
1745 on either the convert or waiting queue.
1746 high is the largest rqmode of all locks blocked on the convert or
1747 waiting queue. */
1748
1749static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
1750{
1751 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
1752 if (gr->lkb_highbast < DLM_LOCK_EX)
1753 return 1;
1754 return 0;
1755 }
1756
1757 if (gr->lkb_highbast < high &&
1758 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
1759 return 1;
1760 return 0;
1761}
1762
e7fd4179
DT		 1763static void grant_pending_locks(struct dlm_rsb *r)
1764{
1765 struct dlm_lkb *lkb, *s;
1766 int high = DLM_LOCK_IV;
36509258 1767 int cw = 0;
e7fd4179 1768
a345da3e 1769 DLM_ASSERT(is_master(r), dlm_dump_rsb(r););
e7fd4179 1770
36509258
DT		 1771 high = grant_pending_convert(r, high, &cw);
1772 high = grant_pending_wait(r, high, &cw);
e7fd4179
DT		 1773
1774 if (high == DLM_LOCK_IV)
1775 return;
1776
1777 /*
1778 * If there are locks left on the wait/convert queue then send blocking
1779 * ASTs to granted locks based on the largest requested mode (high)
36509258 1780 * found above.
e7fd4179
DT		 1781 */
1782
1783 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 1784 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
36509258
DT		 1785 if (cw && high == DLM_LOCK_PR)
1786 queue_bast(r, lkb, DLM_LOCK_CW);
1787 else
1788 queue_bast(r, lkb, high);
e7fd4179
DT		 1789 lkb->lkb_highbast = high;
1790 }
1791 }
1792}
1793
36509258
DT		 1794static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
1795{
1796 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
1797 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
1798 if (gr->lkb_highbast < DLM_LOCK_EX)
1799 return 1;
1800 return 0;
1801 }
1802
1803 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
1804 return 1;
1805 return 0;
1806}
1807
e7fd4179
DT		 1808static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
1809 struct dlm_lkb *lkb)
1810{
1811 struct dlm_lkb *gr;
1812
1813 list_for_each_entry(gr, head, lkb_statequeue) {
e5dae548 1814 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 1815 queue_bast(r, gr, lkb->lkb_rqmode);
1816 gr->lkb_highbast = lkb->lkb_rqmode;
1817 }
1818 }
1819}
1820
1821static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
1822{
1823 send_bast_queue(r, &r->res_grantqueue, lkb);
1824}
1825
1826static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
1827{
1828 send_bast_queue(r, &r->res_grantqueue, lkb);
1829 send_bast_queue(r, &r->res_convertqueue, lkb);
1830}
1831
1832/* set_master(r, lkb) -- set the master nodeid of a resource
1833
1834 The purpose of this function is to set the nodeid field in the given
1835 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
1836 known, it can just be copied to the lkb and the function will return
1837 0. If the rsb's nodeid is _not_ known, it needs to be looked up
1838 before it can be copied to the lkb.
1839
1840 When the rsb nodeid is being looked up remotely, the initial lkb
1841 causing the lookup is kept on the ls_waiters list waiting for the
1842 lookup reply. Other lkb's waiting for the same rsb lookup are kept
1843 on the rsb's res_lookup list until the master is verified.
1844
1845 Return values:
1846 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
1847 1: the rsb master is not available and the lkb has been placed on
1848 a wait queue
1849*/
1850
1851static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
1852{
1853 struct dlm_ls *ls = r->res_ls;
755b5eb8 1854 int i, error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 1855
1856 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
1857 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
1858 r->res_first_lkid = lkb->lkb_id;
1859 lkb->lkb_nodeid = r->res_nodeid;
1860 return 0;
1861 }
1862
1863 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
1864 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
1865 return 1;
1866 }
1867
1868 if (r->res_nodeid == 0) {
1869 lkb->lkb_nodeid = 0;
1870 return 0;
1871 }
1872
1873 if (r->res_nodeid > 0) {
1874 lkb->lkb_nodeid = r->res_nodeid;
1875 return 0;
1876 }
1877
a345da3e 1878 DLM_ASSERT(r->res_nodeid == -1, dlm_dump_rsb(r););
e7fd4179
DT		 1879
1880 dir_nodeid = dlm_dir_nodeid(r);
1881
1882 if (dir_nodeid != our_nodeid) {
1883 r->res_first_lkid = lkb->lkb_id;
1884 send_lookup(r, lkb);
1885 return 1;
1886 }
1887
755b5eb8 1888 for (i = 0; i < 2; i++) {
e7fd4179
DT		 1889 /* It's possible for dlm_scand to remove an old rsb for
1890 this same resource from the toss list, us to create
1891 a new one, look up the master locally, and find it
1892 already exists just before dlm_scand does the
1893 dir_remove() on the previous rsb. */
1894
1895 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
1896 r->res_length, &ret_nodeid);
1897 if (!error)
1898 break;
1899 log_debug(ls, "dir_lookup error %d %s", error, r->res_name);
1900 schedule();
1901 }
755b5eb8
DT		 1902 if (error && error != -EEXIST)
1903 return error;
e7fd4179
DT		 1904
1905 if (ret_nodeid == our_nodeid) {
1906 r->res_first_lkid = 0;
1907 r->res_nodeid = 0;
1908 lkb->lkb_nodeid = 0;
1909 } else {
1910 r->res_first_lkid = lkb->lkb_id;
1911 r->res_nodeid = ret_nodeid;
1912 lkb->lkb_nodeid = ret_nodeid;
1913 }
1914 return 0;
1915}
1916
1917static void process_lookup_list(struct dlm_rsb *r)
1918{
1919 struct dlm_lkb *lkb, *safe;
1920
1921 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 1922 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 1923 _request_lock(r, lkb);
1924 schedule();
1925 }
1926}
1927
1928/* confirm_master -- confirm (or deny) an rsb's master nodeid */
1929
1930static void confirm_master(struct dlm_rsb *r, int error)
1931{
1932 struct dlm_lkb *lkb;
1933
1934 if (!r->res_first_lkid)
1935 return;
1936
1937 switch (error) {
1938 case 0:
1939 case -EINPROGRESS:
1940 r->res_first_lkid = 0;
1941 process_lookup_list(r);
1942 break;
1943
1944 case -EAGAIN:
aec64e1b
DT		 1945 case -EBADR:
1946 case -ENOTBLK:
1947 /* the remote request failed and won't be retried (it was
1948 a NOQUEUE, or has been canceled/unlocked); make a waiting
1949 lkb the first_lkid */
e7fd4179
DT		 1950
1951 r->res_first_lkid = 0;
1952
1953 if (!list_empty(&r->res_lookup)) {
1954 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
1955 lkb_rsb_lookup);
ef0c2bb0 1956 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 1957 r->res_first_lkid = lkb->lkb_id;
1958 _request_lock(r, lkb);
761b9d3f 1959 }
e7fd4179
DT		 1960 break;
1961
1962 default:
1963 log_error(r->res_ls, "confirm_master unknown error %d", error);
1964 }
1965}
1966
1967static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 1968 int namelen, unsigned long timeout_cs,
1969 void (*ast) (void *astparam),
1970 void *astparam,
1971 void (*bast) (void *astparam, int mode),
1972 struct dlm_args *args)
e7fd4179
DT		 1973{
1974 int rv = -EINVAL;
1975
1976 /* check for invalid arg usage */
1977
1978 if (mode < 0 || mode > DLM_LOCK_EX)
1979 goto out;
1980
1981 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
1982 goto out;
1983
1984 if (flags & DLM_LKF_CANCEL)
1985 goto out;
1986
1987 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
1988 goto out;
1989
1990 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
1991 goto out;
1992
1993 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
1994 goto out;
1995
1996 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
1997 goto out;
1998
1999 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2000 goto out;
2001
2002 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2003 goto out;
2004
2005 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2006 goto out;
2007
2008 if (!ast || !lksb)
2009 goto out;
2010
2011 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2012 goto out;
2013
e7fd4179
DT		 2014 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2015 goto out;
2016
2017 /* these args will be copied to the lkb in validate_lock_args,
2018 it cannot be done now because when converting locks, fields in
2019 an active lkb cannot be modified before locking the rsb */
2020
2021 args->flags = flags;
e5dae548
DT		 2022 args->astfn = ast;
2023 args->astparam = astparam;
2024 args->bastfn = bast;
d7db923e 2025 args->timeout = timeout_cs;
e7fd4179
DT		 2026 args->mode = mode;
2027 args->lksb = lksb;
e7fd4179
DT		 2028 rv = 0;
2029 out:
2030 return rv;
2031}
2032
2033static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2034{
2035 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2036 DLM_LKF_FORCEUNLOCK))
2037 return -EINVAL;
2038
ef0c2bb0
DT		 2039 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2040 return -EINVAL;
2041
e7fd4179 2042 args->flags = flags;
e5dae548 2043 args->astparam = astarg;
e7fd4179
DT		 2044 return 0;
2045}
2046
2047static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2048 struct dlm_args *args)
2049{
2050 int rv = -EINVAL;
2051
2052 if (args->flags & DLM_LKF_CONVERT) {
2053 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2054 goto out;
2055
2056 if (args->flags & DLM_LKF_QUECVT &&
2057 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2058 goto out;
2059
2060 rv = -EBUSY;
2061 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2062 goto out;
2063
2064 if (lkb->lkb_wait_type)
2065 goto out;
ef0c2bb0
DT		 2066
2067 if (is_overlap(lkb))
2068 goto out;
e7fd4179
DT		 2069 }
2070
2071 lkb->lkb_exflags = args->flags;
2072 lkb->lkb_sbflags = 0;
e5dae548 2073 lkb->lkb_astfn = args->astfn;
e7fd4179 2074 lkb->lkb_astparam = args->astparam;
e5dae548 2075 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2076 lkb->lkb_rqmode = args->mode;
2077 lkb->lkb_lksb = args->lksb;
2078 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2079 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2080 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2081 rv = 0;
2082 out:
2083 return rv;
2084}
2085
ef0c2bb0
DT		 2086/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2087 for success */
2088
2089/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2090 because there may be a lookup in progress and it's valid to do
2091 cancel/unlockf on it */
2092
e7fd4179
DT		 2093static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2094{
ef0c2bb0 2095 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2096 int rv = -EINVAL;
2097
ef0c2bb0
DT		 2098 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2099 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2100 dlm_print_lkb(lkb);
e7fd4179 2101 goto out;
ef0c2bb0 2102 }
e7fd4179 2103
ef0c2bb0
DT		 2104 /* an lkb may still exist even though the lock is EOL'ed due to a
2105 cancel, unlock or failed noqueue request; an app can't use these
2106 locks; return same error as if the lkid had not been found at all */
e7fd4179 2107
ef0c2bb0
DT		 2108 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2109 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2110 rv = -ENOENT;
e7fd4179 2111 goto out;
ef0c2bb0 2112 }
e7fd4179 2113
ef0c2bb0
DT		 2114 /* an lkb may be waiting for an rsb lookup to complete where the
2115 lookup was initiated by another lock */
2116
42dc1601
DT		 2117 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2118 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2119 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2120 list_del_init(&lkb->lkb_rsb_lookup);
2121 queue_cast(lkb->lkb_resource, lkb,
2122 args->flags & DLM_LKF_CANCEL ?
2123 -DLM_ECANCEL : -DLM_EUNLOCK);
2124 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2125 }
42dc1601
DT		 2126 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2127 rv = -EBUSY;
2128 goto out;
ef0c2bb0
DT		 2129 }
2130
2131 /* cancel not allowed with another cancel/unlock in progress */
2132
2133 if (args->flags & DLM_LKF_CANCEL) {
2134 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2135 goto out;
2136
2137 if (is_overlap(lkb))
2138 goto out;
2139
3ae1acf9
DT		 2140 /* don't let scand try to do a cancel */
2141 del_timeout(lkb);
2142
ef0c2bb0
DT		 2143 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2144 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2145 rv = -EBUSY;
2146 goto out;
2147 }
2148
2149 switch (lkb->lkb_wait_type) {
2150 case DLM_MSG_LOOKUP:
2151 case DLM_MSG_REQUEST:
2152 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2153 rv = -EBUSY;
2154 goto out;
2155 case DLM_MSG_UNLOCK:
2156 case DLM_MSG_CANCEL:
2157 goto out;
2158 }
2159 /* add_to_waiters() will set OVERLAP_CANCEL */
2160 goto out_ok;
2161 }
2162
2163 /* do we need to allow a force-unlock if there's a normal unlock
2164 already in progress? in what conditions could the normal unlock
2165 fail such that we'd want to send a force-unlock to be sure? */
2166
2167 if (args->flags & DLM_LKF_FORCEUNLOCK) {
2168 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
2169 goto out;
2170
2171 if (is_overlap_unlock(lkb))
2172 goto out;
e7fd4179 2173
3ae1acf9
DT		 2174 /* don't let scand try to do a cancel */
2175 del_timeout(lkb);
2176
ef0c2bb0
DT		 2177 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2178 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2179 rv = -EBUSY;
2180 goto out;
2181 }
2182
2183 switch (lkb->lkb_wait_type) {
2184 case DLM_MSG_LOOKUP:
2185 case DLM_MSG_REQUEST:
2186 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2187 rv = -EBUSY;
2188 goto out;
2189 case DLM_MSG_UNLOCK:
2190 goto out;
2191 }
2192 /* add_to_waiters() will set OVERLAP_UNLOCK */
2193 goto out_ok;
2194 }
2195
2196 /* normal unlock not allowed if there's any op in progress */
e7fd4179 2197 rv = -EBUSY;
ef0c2bb0 2198 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 2199 goto out;
2200
2201 out_ok:
ef0c2bb0
DT		 2202 /* an overlapping op shouldn't blow away exflags from other op */
2203 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 2204 lkb->lkb_sbflags = 0;
2205 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 2206 rv = 0;
2207 out:
ef0c2bb0
DT		 2208 if (rv)
2209 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
2210 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
2211 args->flags, lkb->lkb_wait_type,
2212 lkb->lkb_resource->res_name);
e7fd4179
DT		 2213 return rv;
2214}
2215
2216/*
2217 * Four stage 4 varieties:
2218 * do_request(), do_convert(), do_unlock(), do_cancel()
2219 * These are called on the master node for the given lock and
2220 * from the central locking logic.
2221 */
2222
2223static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2224{
2225 int error = 0;
2226
c85d65e9 2227 if (can_be_granted(r, lkb, 1, NULL)) {
e7fd4179
DT		 2228 grant_lock(r, lkb);
2229 queue_cast(r, lkb, 0);
2230 goto out;
2231 }
2232
2233 if (can_be_queued(lkb)) {
2234 error = -EINPROGRESS;
2235 add_lkb(r, lkb, DLM_LKSTS_WAITING);
2236 send_blocking_asts(r, lkb);
3ae1acf9 2237 add_timeout(lkb);
e7fd4179
DT		 2238 goto out;
2239 }
2240
2241 error = -EAGAIN;
2242 if (force_blocking_asts(lkb))
2243 send_blocking_asts_all(r, lkb);
2244 queue_cast(r, lkb, -EAGAIN);
2245
2246 out:
2247 return error;
2248}
2249
2250static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2251{
2252 int error = 0;
c85d65e9 2253 int deadlk = 0;
e7fd4179
DT		 2254
2255 /* changing an existing lock may allow others to be granted */
2256
c85d65e9 2257 if (can_be_granted(r, lkb, 1, &deadlk)) {
e7fd4179
DT		 2258 grant_lock(r, lkb);
2259 queue_cast(r, lkb, 0);
2260 grant_pending_locks(r);
2261 goto out;
2262 }
2263
c85d65e9
DT		 2264 /* can_be_granted() detected that this lock would block in a conversion
2265 deadlock, so we leave it on the granted queue and return EDEADLK in
2266 the ast for the convert. */
2267
2268 if (deadlk) {
2269 /* it's left on the granted queue */
2270 log_debug(r->res_ls, "deadlock %x node %d sts%d g%d r%d %s",
2271 lkb->lkb_id, lkb->lkb_nodeid, lkb->lkb_status,
2272 lkb->lkb_grmode, lkb->lkb_rqmode, r->res_name);
2273 revert_lock(r, lkb);
2274 queue_cast(r, lkb, -EDEADLK);
2275 error = -EDEADLK;
2276 goto out;
2277 }
2278
7d3c1feb
DT		 2279 /* is_demoted() means the can_be_granted() above set the grmode
2280 to NL, and left us on the granted queue. This auto-demotion
2281 (due to CONVDEADLK) might mean other locks, and/or this lock, are
2282 now grantable. We have to try to grant other converting locks
2283 before we try again to grant this one. */
2284
2285 if (is_demoted(lkb)) {
36509258 2286 grant_pending_convert(r, DLM_LOCK_IV, NULL);
7d3c1feb
DT		 2287 if (_can_be_granted(r, lkb, 1)) {
2288 grant_lock(r, lkb);
2289 queue_cast(r, lkb, 0);
e7fd4179 2290 grant_pending_locks(r);
7d3c1feb
DT		 2291 goto out;
2292 }
2293 /* else fall through and move to convert queue */
2294 }
2295
2296 if (can_be_queued(lkb)) {
e7fd4179
DT		 2297 error = -EINPROGRESS;
2298 del_lkb(r, lkb);
2299 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
2300 send_blocking_asts(r, lkb);
3ae1acf9 2301 add_timeout(lkb);
e7fd4179
DT		 2302 goto out;
2303 }
2304
2305 error = -EAGAIN;
2306 if (force_blocking_asts(lkb))
2307 send_blocking_asts_all(r, lkb);
2308 queue_cast(r, lkb, -EAGAIN);
2309
2310 out:
2311 return error;
2312}
2313
2314static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2315{
2316 remove_lock(r, lkb);
2317 queue_cast(r, lkb, -DLM_EUNLOCK);
2318 grant_pending_locks(r);
2319 return -DLM_EUNLOCK;
2320}
2321
ef0c2bb0 2322/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
907b9bce 2323
e7fd4179
DT		 2324static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2325{
ef0c2bb0
DT		 2326 int error;
2327
2328 error = revert_lock(r, lkb);
2329 if (error) {
2330 queue_cast(r, lkb, -DLM_ECANCEL);
2331 grant_pending_locks(r);
2332 return -DLM_ECANCEL;
2333 }
2334 return 0;
e7fd4179
DT		 2335}
2336
2337/*
2338 * Four stage 3 varieties:
2339 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
2340 */
2341
2342/* add a new lkb to a possibly new rsb, called by requesting process */
2343
2344static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2345{
2346 int error;
2347
2348 /* set_master: sets lkb nodeid from r */
2349
2350 error = set_master(r, lkb);
2351 if (error < 0)
2352 goto out;
2353 if (error) {
2354 error = 0;
2355 goto out;
2356 }
2357
2358 if (is_remote(r))
2359 /* receive_request() calls do_request() on remote node */
2360 error = send_request(r, lkb);
2361 else
2362 error = do_request(r, lkb);
2363 out:
2364 return error;
2365}
2366
3bcd3687 2367/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 2368
2369static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2370{
2371 int error;
2372
2373 if (is_remote(r))
2374 /* receive_convert() calls do_convert() on remote node */
2375 error = send_convert(r, lkb);
2376 else
2377 error = do_convert(r, lkb);
2378
2379 return error;
2380}
2381
2382/* remove an existing lkb from the granted queue */
2383
2384static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2385{
2386 int error;
2387
2388 if (is_remote(r))
2389 /* receive_unlock() calls do_unlock() on remote node */
2390 error = send_unlock(r, lkb);
2391 else
2392 error = do_unlock(r, lkb);
2393
2394 return error;
2395}
2396
2397/* remove an existing lkb from the convert or wait queue */
2398
2399static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2400{
2401 int error;
2402
2403 if (is_remote(r))
2404 /* receive_cancel() calls do_cancel() on remote node */
2405 error = send_cancel(r, lkb);
2406 else
2407 error = do_cancel(r, lkb);
2408
2409 return error;
2410}
2411
2412/*
2413 * Four stage 2 varieties:
2414 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
2415 */
2416
2417static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
2418 int len, struct dlm_args *args)
2419{
2420 struct dlm_rsb *r;
2421 int error;
2422
2423 error = validate_lock_args(ls, lkb, args);
2424 if (error)
2425 goto out;
2426
2427 error = find_rsb(ls, name, len, R_CREATE, &r);
2428 if (error)
2429 goto out;
2430
2431 lock_rsb(r);
2432
2433 attach_lkb(r, lkb);
2434 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
2435
2436 error = _request_lock(r, lkb);
2437
2438 unlock_rsb(r);
2439 put_rsb(r);
2440
2441 out:
2442 return error;
2443}
2444
2445static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2446 struct dlm_args *args)
2447{
2448 struct dlm_rsb *r;
2449 int error;
2450
2451 r = lkb->lkb_resource;
2452
2453 hold_rsb(r);
2454 lock_rsb(r);
2455
2456 error = validate_lock_args(ls, lkb, args);
2457 if (error)
2458 goto out;
2459
2460 error = _convert_lock(r, lkb);
2461 out:
2462 unlock_rsb(r);
2463 put_rsb(r);
2464 return error;
2465}
2466
2467static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2468 struct dlm_args *args)
2469{
2470 struct dlm_rsb *r;
2471 int error;
2472
2473 r = lkb->lkb_resource;
2474
2475 hold_rsb(r);
2476 lock_rsb(r);
2477
2478 error = validate_unlock_args(lkb, args);
2479 if (error)
2480 goto out;
2481
2482 error = _unlock_lock(r, lkb);
2483 out:
2484 unlock_rsb(r);
2485 put_rsb(r);
2486 return error;
2487}
2488
2489static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2490 struct dlm_args *args)
2491{
2492 struct dlm_rsb *r;
2493 int error;
2494
2495 r = lkb->lkb_resource;
2496
2497 hold_rsb(r);
2498 lock_rsb(r);
2499
2500 error = validate_unlock_args(lkb, args);
2501 if (error)
2502 goto out;
2503
2504 error = _cancel_lock(r, lkb);
2505 out:
2506 unlock_rsb(r);
2507 put_rsb(r);
2508 return error;
2509}
2510
2511/*
2512 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
2513 */
2514
2515int dlm_lock(dlm_lockspace_t *lockspace,
2516 int mode,
2517 struct dlm_lksb *lksb,
2518 uint32_t flags,
2519 void *name,
2520 unsigned int namelen,
2521 uint32_t parent_lkid,
2522 void (*ast) (void *astarg),
2523 void *astarg,
3bcd3687 2524 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 2525{
2526 struct dlm_ls *ls;
2527 struct dlm_lkb *lkb;
2528 struct dlm_args args;
2529 int error, convert = flags & DLM_LKF_CONVERT;
2530
2531 ls = dlm_find_lockspace_local(lockspace);
2532 if (!ls)
2533 return -EINVAL;
2534
85e86edf 2535 dlm_lock_recovery(ls);
e7fd4179
DT		 2536
2537 if (convert)
2538 error = find_lkb(ls, lksb->sb_lkid, &lkb);
2539 else
2540 error = create_lkb(ls, &lkb);
2541
2542 if (error)
2543 goto out;
2544
d7db923e 2545 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 2546 astarg, bast, &args);
e7fd4179
DT		 2547 if (error)
2548 goto out_put;
2549
2550 if (convert)
2551 error = convert_lock(ls, lkb, &args);
2552 else
2553 error = request_lock(ls, lkb, name, namelen, &args);
2554
2555 if (error == -EINPROGRESS)
2556 error = 0;
2557 out_put:
2558 if (convert || error)
b3f58d8f 2559 __put_lkb(ls, lkb);
c85d65e9 2560 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 2561 error = 0;
2562 out:
85e86edf 2563 dlm_unlock_recovery(ls);
e7fd4179
DT		 2564 dlm_put_lockspace(ls);
2565 return error;
2566}
2567
2568int dlm_unlock(dlm_lockspace_t *lockspace,
2569 uint32_t lkid,
2570 uint32_t flags,
2571 struct dlm_lksb *lksb,
2572 void *astarg)
2573{
2574 struct dlm_ls *ls;
2575 struct dlm_lkb *lkb;
2576 struct dlm_args args;
2577 int error;
2578
2579 ls = dlm_find_lockspace_local(lockspace);
2580 if (!ls)
2581 return -EINVAL;
2582
85e86edf 2583 dlm_lock_recovery(ls);
e7fd4179
DT		 2584
2585 error = find_lkb(ls, lkid, &lkb);
2586 if (error)
2587 goto out;
2588
2589 error = set_unlock_args(flags, astarg, &args);
2590 if (error)
2591 goto out_put;
2592
2593 if (flags & DLM_LKF_CANCEL)
2594 error = cancel_lock(ls, lkb, &args);
2595 else
2596 error = unlock_lock(ls, lkb, &args);
2597
2598 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
2599 error = 0;
ef0c2bb0
DT		 2600 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
2601 error = 0;
e7fd4179 2602 out_put:
b3f58d8f 2603 dlm_put_lkb(lkb);
e7fd4179 2604 out:
85e86edf 2605 dlm_unlock_recovery(ls);
e7fd4179
DT		 2606 dlm_put_lockspace(ls);
2607 return error;
2608}
2609
2610/*
2611 * send/receive routines for remote operations and replies
2612 *
2613 * send_args
2614 * send_common
2615 * send_request receive_request
2616 * send_convert receive_convert
2617 * send_unlock receive_unlock
2618 * send_cancel receive_cancel
2619 * send_grant receive_grant
2620 * send_bast receive_bast
2621 * send_lookup receive_lookup
2622 * send_remove receive_remove
2623 *
2624 * send_common_reply
2625 * receive_request_reply send_request_reply
2626 * receive_convert_reply send_convert_reply
2627 * receive_unlock_reply send_unlock_reply
2628 * receive_cancel_reply send_cancel_reply
2629 * receive_lookup_reply send_lookup_reply
2630 */
2631
7e4dac33
DT		 2632static int _create_message(struct dlm_ls *ls, int mb_len,
2633 int to_nodeid, int mstype,
2634 struct dlm_message **ms_ret,
2635 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 2636{
2637 struct dlm_message *ms;
2638 struct dlm_mhandle *mh;
2639 char *mb;
e7fd4179
DT		 2640
2641 /* get_buffer gives us a message handle (mh) that we need to
2642 pass into lowcomms_commit and a message buffer (mb) that we
2643 write our data into */
2644
44f487a5 2645 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, ls->ls_allocation, &mb);
e7fd4179
DT		 2646 if (!mh)
2647 return -ENOBUFS;
2648
2649 memset(mb, 0, mb_len);
2650
2651 ms = (struct dlm_message *) mb;
2652
2653 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 2654 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 2655 ms->m_header.h_nodeid = dlm_our_nodeid();
2656 ms->m_header.h_length = mb_len;
2657 ms->m_header.h_cmd = DLM_MSG;
2658
2659 ms->m_type = mstype;
2660
2661 *mh_ret = mh;
2662 *ms_ret = ms;
2663 return 0;
2664}
2665
7e4dac33
DT		 2666static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
2667 int to_nodeid, int mstype,
2668 struct dlm_message **ms_ret,
2669 struct dlm_mhandle **mh_ret)
2670{
2671 int mb_len = sizeof(struct dlm_message);
2672
2673 switch (mstype) {
2674 case DLM_MSG_REQUEST:
2675 case DLM_MSG_LOOKUP:
2676 case DLM_MSG_REMOVE:
2677 mb_len += r->res_length;
2678 break;
2679 case DLM_MSG_CONVERT:
2680 case DLM_MSG_UNLOCK:
2681 case DLM_MSG_REQUEST_REPLY:
2682 case DLM_MSG_CONVERT_REPLY:
2683 case DLM_MSG_GRANT:
2684 if (lkb && lkb->lkb_lvbptr)
2685 mb_len += r->res_ls->ls_lvblen;
2686 break;
2687 }
2688
2689 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
2690 ms_ret, mh_ret);
2691}
2692
e7fd4179
DT		 2693/* further lowcomms enhancements or alternate implementations may make
2694 the return value from this function useful at some point */
2695
2696static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
2697{
2698 dlm_message_out(ms);
2699 dlm_lowcomms_commit_buffer(mh);
2700 return 0;
2701}
2702
2703static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
2704 struct dlm_message *ms)
2705{
2706 ms->m_nodeid = lkb->lkb_nodeid;
2707 ms->m_pid = lkb->lkb_ownpid;
2708 ms->m_lkid = lkb->lkb_id;
2709 ms->m_remid = lkb->lkb_remid;
2710 ms->m_exflags = lkb->lkb_exflags;
2711 ms->m_sbflags = lkb->lkb_sbflags;
2712 ms->m_flags = lkb->lkb_flags;
2713 ms->m_lvbseq = lkb->lkb_lvbseq;
2714 ms->m_status = lkb->lkb_status;
2715 ms->m_grmode = lkb->lkb_grmode;
2716 ms->m_rqmode = lkb->lkb_rqmode;
2717 ms->m_hash = r->res_hash;
2718
2719 /* m_result and m_bastmode are set from function args,
2720 not from lkb fields */
2721
e5dae548 2722 if (lkb->lkb_bastfn)
e7fd4179 2723 ms->m_asts |= AST_BAST;
e5dae548 2724 if (lkb->lkb_astfn)
e7fd4179
DT		 2725 ms->m_asts |= AST_COMP;
2726
da49f36f
DT		 2727 /* compare with switch in create_message; send_remove() doesn't
2728 use send_args() */
e7fd4179 2729
da49f36f
DT		 2730 switch (ms->m_type) {
2731 case DLM_MSG_REQUEST:
2732 case DLM_MSG_LOOKUP:
2733 memcpy(ms->m_extra, r->res_name, r->res_length);
2734 break;
2735 case DLM_MSG_CONVERT:
2736 case DLM_MSG_UNLOCK:
2737 case DLM_MSG_REQUEST_REPLY:
2738 case DLM_MSG_CONVERT_REPLY:
2739 case DLM_MSG_GRANT:
2740 if (!lkb->lkb_lvbptr)
2741 break;
e7fd4179 2742 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 2743 break;
2744 }
e7fd4179
DT		 2745}
2746
2747static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
2748{
2749 struct dlm_message *ms;
2750 struct dlm_mhandle *mh;
2751 int to_nodeid, error;
2752
ef0c2bb0
DT		 2753 error = add_to_waiters(lkb, mstype);
2754 if (error)
2755 return error;
e7fd4179
DT		 2756
2757 to_nodeid = r->res_nodeid;
2758
2759 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
2760 if (error)
2761 goto fail;
2762
2763 send_args(r, lkb, ms);
2764
2765 error = send_message(mh, ms);
2766 if (error)
2767 goto fail;
2768 return 0;
2769
2770 fail:
ef0c2bb0 2771 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 2772 return error;
2773}
2774
2775static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2776{
2777 return send_common(r, lkb, DLM_MSG_REQUEST);
2778}
2779
2780static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2781{
2782 int error;
2783
2784 error = send_common(r, lkb, DLM_MSG_CONVERT);
2785
2786 /* down conversions go without a reply from the master */
2787 if (!error && down_conversion(lkb)) {
ef0c2bb0
DT		 2788 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2789 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179 2790 r->res_ls->ls_stub_ms.m_result = 0;
32f105a1 2791 r->res_ls->ls_stub_ms.m_flags = lkb->lkb_flags;
e7fd4179
DT		 2792 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
2793 }
2794
2795 return error;
2796}
2797
2798/* FIXME: if this lkb is the only lock we hold on the rsb, then set
2799 MASTER_UNCERTAIN to force the next request on the rsb to confirm
2800 that the master is still correct. */
2801
2802static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2803{
2804 return send_common(r, lkb, DLM_MSG_UNLOCK);
2805}
2806
2807static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2808{
2809 return send_common(r, lkb, DLM_MSG_CANCEL);
2810}
2811
2812static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
2813{
2814 struct dlm_message *ms;
2815 struct dlm_mhandle *mh;
2816 int to_nodeid, error;
2817
2818 to_nodeid = lkb->lkb_nodeid;
2819
2820 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
2821 if (error)
2822 goto out;
2823
2824 send_args(r, lkb, ms);
2825
2826 ms->m_result = 0;
2827
2828 error = send_message(mh, ms);
2829 out:
2830 return error;
2831}
2832
2833static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
2834{
2835 struct dlm_message *ms;
2836 struct dlm_mhandle *mh;
2837 int to_nodeid, error;
2838
2839 to_nodeid = lkb->lkb_nodeid;
2840
2841 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
2842 if (error)
2843 goto out;
2844
2845 send_args(r, lkb, ms);
2846
2847 ms->m_bastmode = mode;
2848
2849 error = send_message(mh, ms);
2850 out:
2851 return error;
2852}
2853
2854static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
2855{
2856 struct dlm_message *ms;
2857 struct dlm_mhandle *mh;
2858 int to_nodeid, error;
2859
ef0c2bb0
DT		 2860 error = add_to_waiters(lkb, DLM_MSG_LOOKUP);
2861 if (error)
2862 return error;
e7fd4179
DT		 2863
2864 to_nodeid = dlm_dir_nodeid(r);
2865
2866 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
2867 if (error)
2868 goto fail;
2869
2870 send_args(r, lkb, ms);
2871
2872 error = send_message(mh, ms);
2873 if (error)
2874 goto fail;
2875 return 0;
2876
2877 fail:
ef0c2bb0 2878 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 2879 return error;
2880}
2881
2882static int send_remove(struct dlm_rsb *r)
2883{
2884 struct dlm_message *ms;
2885 struct dlm_mhandle *mh;
2886 int to_nodeid, error;
2887
2888 to_nodeid = dlm_dir_nodeid(r);
2889
2890 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
2891 if (error)
2892 goto out;
2893
2894 memcpy(ms->m_extra, r->res_name, r->res_length);
2895 ms->m_hash = r->res_hash;
2896
2897 error = send_message(mh, ms);
2898 out:
2899 return error;
2900}
2901
2902static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
2903 int mstype, int rv)
2904{
2905 struct dlm_message *ms;
2906 struct dlm_mhandle *mh;
2907 int to_nodeid, error;
2908
2909 to_nodeid = lkb->lkb_nodeid;
2910
2911 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
2912 if (error)
2913 goto out;
2914
2915 send_args(r, lkb, ms);
2916
2917 ms->m_result = rv;
2918
2919 error = send_message(mh, ms);
2920 out:
2921 return error;
2922}
2923
2924static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2925{
2926 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
2927}
2928
2929static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2930{
2931 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
2932}
2933
2934static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2935{
2936 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
2937}
2938
2939static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2940{
2941 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
2942}
2943
2944static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
2945 int ret_nodeid, int rv)
2946{
2947 struct dlm_rsb *r = &ls->ls_stub_rsb;
2948 struct dlm_message *ms;
2949 struct dlm_mhandle *mh;
2950 int error, nodeid = ms_in->m_header.h_nodeid;
2951
2952 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
2953 if (error)
2954 goto out;
2955
2956 ms->m_lkid = ms_in->m_lkid;
2957 ms->m_result = rv;
2958 ms->m_nodeid = ret_nodeid;
2959
2960 error = send_message(mh, ms);
2961 out:
2962 return error;
2963}
2964
2965/* which args we save from a received message depends heavily on the type
2966 of message, unlike the send side where we can safely send everything about
2967 the lkb for any type of message */
2968
2969static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
2970{
2971 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 2972 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 2973 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
2974 (ms->m_flags & 0x0000FFFF);
2975}
2976
2977static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
2978{
2979 lkb->lkb_sbflags = ms->m_sbflags;
2980 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
2981 (ms->m_flags & 0x0000FFFF);
2982}
2983
2984static int receive_extralen(struct dlm_message *ms)
2985{
2986 return (ms->m_header.h_length - sizeof(struct dlm_message));
2987}
2988
e7fd4179
DT		 2989static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
2990 struct dlm_message *ms)
2991{
2992 int len;
2993
2994 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
2995 if (!lkb->lkb_lvbptr)
52bda2b5 2996 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 2997 if (!lkb->lkb_lvbptr)
2998 return -ENOMEM;
2999 len = receive_extralen(ms);
a9cc9159
AV		 3000 if (len > DLM_RESNAME_MAXLEN)
3001 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 3002 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3003 }
3004 return 0;
3005}
3006
e5dae548
DT		 3007static void fake_bastfn(void *astparam, int mode)
3008{
3009 log_print("fake_bastfn should not be called");
3010}
3011
3012static void fake_astfn(void *astparam)
3013{
3014 log_print("fake_astfn should not be called");
3015}
3016
e7fd4179
DT		 3017static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3018 struct dlm_message *ms)
3019{
3020 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3021 lkb->lkb_ownpid = ms->m_pid;
3022 lkb->lkb_remid = ms->m_lkid;
3023 lkb->lkb_grmode = DLM_LOCK_IV;
3024 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548
DT		 3025
3026 lkb->lkb_bastfn = (ms->m_asts & AST_BAST) ? &fake_bastfn : NULL;
3027 lkb->lkb_astfn = (ms->m_asts & AST_COMP) ? &fake_astfn : NULL;
e7fd4179 3028
8d07fd50
DT		 3029 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3030 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3031 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3032 if (!lkb->lkb_lvbptr)
3033 return -ENOMEM;
3034 }
e7fd4179
DT		 3035
3036 return 0;
3037}
3038
3039static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3040 struct dlm_message *ms)
3041{
e7fd4179
DT		 3042 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3043 return -EBUSY;
3044
e7fd4179
DT		 3045 if (receive_lvb(ls, lkb, ms))
3046 return -ENOMEM;
3047
3048 lkb->lkb_rqmode = ms->m_rqmode;
3049 lkb->lkb_lvbseq = ms->m_lvbseq;
3050
3051 return 0;
3052}
3053
3054static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3055 struct dlm_message *ms)
3056{
e7fd4179
DT		 3057 if (receive_lvb(ls, lkb, ms))
3058 return -ENOMEM;
3059 return 0;
3060}
3061
3062/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3063 uses to send a reply and that the remote end uses to process the reply. */
3064
3065static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3066{
3067 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3068 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3069 lkb->lkb_remid = ms->m_lkid;
3070}
3071
c54e04b0
DT		 3072/* This is called after the rsb is locked so that we can safely inspect
3073 fields in the lkb. */
3074
3075static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3076{
3077 int from = ms->m_header.h_nodeid;
3078 int error = 0;
3079
3080 switch (ms->m_type) {
3081 case DLM_MSG_CONVERT:
3082 case DLM_MSG_UNLOCK:
3083 case DLM_MSG_CANCEL:
3084 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3085 error = -EINVAL;
3086 break;
3087
3088 case DLM_MSG_CONVERT_REPLY:
3089 case DLM_MSG_UNLOCK_REPLY:
3090 case DLM_MSG_CANCEL_REPLY:
3091 case DLM_MSG_GRANT:
3092 case DLM_MSG_BAST:
3093 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3094 error = -EINVAL;
3095 break;
3096
3097 case DLM_MSG_REQUEST_REPLY:
3098 if (!is_process_copy(lkb))
3099 error = -EINVAL;
3100 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3101 error = -EINVAL;
3102 break;
3103
3104 default:
3105 error = -EINVAL;
3106 }
3107
3108 if (error)
3109 log_error(lkb->lkb_resource->res_ls,
3110 "ignore invalid message %d from %d %x %x %x %d",
3111 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
3112 lkb->lkb_flags, lkb->lkb_nodeid);
3113 return error;
3114}
3115
e7fd4179
DT		 3116static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
3117{
3118 struct dlm_lkb *lkb;
3119 struct dlm_rsb *r;
3120 int error, namelen;
3121
3122 error = create_lkb(ls, &lkb);
3123 if (error)
3124 goto fail;
3125
3126 receive_flags(lkb, ms);
3127 lkb->lkb_flags |= DLM_IFL_MSTCPY;
3128 error = receive_request_args(ls, lkb, ms);
3129 if (error) {
b3f58d8f 3130 __put_lkb(ls, lkb);
e7fd4179
DT		 3131 goto fail;
3132 }
3133
3134 namelen = receive_extralen(ms);
3135
3136 error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r);
3137 if (error) {
b3f58d8f 3138 __put_lkb(ls, lkb);
e7fd4179
DT		 3139 goto fail;
3140 }
3141
3142 lock_rsb(r);
3143
3144 attach_lkb(r, lkb);
3145 error = do_request(r, lkb);
3146 send_request_reply(r, lkb, error);
3147
3148 unlock_rsb(r);
3149 put_rsb(r);
3150
3151 if (error == -EINPROGRESS)
3152 error = 0;
3153 if (error)
b3f58d8f 3154 dlm_put_lkb(lkb);
e7fd4179
DT		 3155 return;
3156
3157 fail:
3158 setup_stub_lkb(ls, ms);
3159 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3160}
3161
3162static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
3163{
3164 struct dlm_lkb *lkb;
3165 struct dlm_rsb *r;
90135925 3166 int error, reply = 1;
e7fd4179
DT		 3167
3168 error = find_lkb(ls, ms->m_remid, &lkb);
3169 if (error)
3170 goto fail;
3171
3172 r = lkb->lkb_resource;
3173
3174 hold_rsb(r);
3175 lock_rsb(r);
3176
c54e04b0
DT		 3177 error = validate_message(lkb, ms);
3178 if (error)
3179 goto out;
3180
e7fd4179
DT		 3181 receive_flags(lkb, ms);
3182 error = receive_convert_args(ls, lkb, ms);
3183 if (error)
c54e04b0 3184 goto out_reply;
e7fd4179
DT		 3185 reply = !down_conversion(lkb);
3186
3187 error = do_convert(r, lkb);
c54e04b0 3188 out_reply:
e7fd4179
DT		 3189 if (reply)
3190 send_convert_reply(r, lkb, error);
c54e04b0 3191 out:
e7fd4179
DT		 3192 unlock_rsb(r);
3193 put_rsb(r);
b3f58d8f 3194 dlm_put_lkb(lkb);
e7fd4179
DT		 3195 return;
3196
3197 fail:
3198 setup_stub_lkb(ls, ms);
3199 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3200}
3201
3202static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
3203{
3204 struct dlm_lkb *lkb;
3205 struct dlm_rsb *r;
3206 int error;
3207
3208 error = find_lkb(ls, ms->m_remid, &lkb);
3209 if (error)
3210 goto fail;
3211
3212 r = lkb->lkb_resource;
3213
3214 hold_rsb(r);
3215 lock_rsb(r);
3216
c54e04b0
DT		 3217 error = validate_message(lkb, ms);
3218 if (error)
3219 goto out;
3220
e7fd4179
DT		 3221 receive_flags(lkb, ms);
3222 error = receive_unlock_args(ls, lkb, ms);
3223 if (error)
c54e04b0 3224 goto out_reply;
e7fd4179
DT		 3225
3226 error = do_unlock(r, lkb);
c54e04b0 3227 out_reply:
e7fd4179 3228 send_unlock_reply(r, lkb, error);
c54e04b0 3229 out:
e7fd4179
DT		 3230 unlock_rsb(r);
3231 put_rsb(r);
b3f58d8f 3232 dlm_put_lkb(lkb);
e7fd4179
DT		 3233 return;
3234
3235 fail:
3236 setup_stub_lkb(ls, ms);
3237 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3238}
3239
3240static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
3241{
3242 struct dlm_lkb *lkb;
3243 struct dlm_rsb *r;
3244 int error;
3245
3246 error = find_lkb(ls, ms->m_remid, &lkb);
3247 if (error)
3248 goto fail;
3249
3250 receive_flags(lkb, ms);
3251
3252 r = lkb->lkb_resource;
3253
3254 hold_rsb(r);
3255 lock_rsb(r);
3256
c54e04b0
DT		 3257 error = validate_message(lkb, ms);
3258 if (error)
3259 goto out;
3260
e7fd4179
DT		 3261 error = do_cancel(r, lkb);
3262 send_cancel_reply(r, lkb, error);
c54e04b0 3263 out:
e7fd4179
DT		 3264 unlock_rsb(r);
3265 put_rsb(r);
b3f58d8f 3266 dlm_put_lkb(lkb);
e7fd4179
DT		 3267 return;
3268
3269 fail:
3270 setup_stub_lkb(ls, ms);
3271 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3272}
3273
3274static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
3275{
3276 struct dlm_lkb *lkb;
3277 struct dlm_rsb *r;
3278 int error;
3279
3280 error = find_lkb(ls, ms->m_remid, &lkb);
3281 if (error) {
c54e04b0
DT		 3282 log_debug(ls, "receive_grant from %d no lkb %x",
3283 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3284 return;
3285 }
e7fd4179
DT		 3286
3287 r = lkb->lkb_resource;
3288
3289 hold_rsb(r);
3290 lock_rsb(r);
3291
c54e04b0
DT		 3292 error = validate_message(lkb, ms);
3293 if (error)
3294 goto out;
3295
e7fd4179 3296 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 3297 if (is_altmode(lkb))
3298 munge_altmode(lkb, ms);
e7fd4179
DT		 3299 grant_lock_pc(r, lkb, ms);
3300 queue_cast(r, lkb, 0);
c54e04b0 3301 out:
e7fd4179
DT		 3302 unlock_rsb(r);
3303 put_rsb(r);
b3f58d8f 3304 dlm_put_lkb(lkb);
e7fd4179
DT		 3305}
3306
3307static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
3308{
3309 struct dlm_lkb *lkb;
3310 struct dlm_rsb *r;
3311 int error;
3312
3313 error = find_lkb(ls, ms->m_remid, &lkb);
3314 if (error) {
c54e04b0
DT		 3315 log_debug(ls, "receive_bast from %d no lkb %x",
3316 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3317 return;
3318 }
e7fd4179
DT		 3319
3320 r = lkb->lkb_resource;
3321
3322 hold_rsb(r);
3323 lock_rsb(r);
3324
c54e04b0
DT		 3325 error = validate_message(lkb, ms);
3326 if (error)
3327 goto out;
e7fd4179 3328
c54e04b0
DT		 3329 queue_bast(r, lkb, ms->m_bastmode);
3330 out:
e7fd4179
DT		 3331 unlock_rsb(r);
3332 put_rsb(r);
b3f58d8f 3333 dlm_put_lkb(lkb);
e7fd4179
DT		 3334}
3335
3336static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
3337{
3338 int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid;
3339
3340 from_nodeid = ms->m_header.h_nodeid;
3341 our_nodeid = dlm_our_nodeid();
3342
3343 len = receive_extralen(ms);
3344
3345 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3346 if (dir_nodeid != our_nodeid) {
3347 log_error(ls, "lookup dir_nodeid %d from %d",
3348 dir_nodeid, from_nodeid);
3349 error = -EINVAL;
3350 ret_nodeid = -1;
3351 goto out;
3352 }
3353
3354 error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid);
3355
3356 /* Optimization: we're master so treat lookup as a request */
3357 if (!error && ret_nodeid == our_nodeid) {
3358 receive_request(ls, ms);
3359 return;
3360 }
3361 out:
3362 send_lookup_reply(ls, ms, ret_nodeid, error);
3363}
3364
3365static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
3366{
3367 int len, dir_nodeid, from_nodeid;
3368
3369 from_nodeid = ms->m_header.h_nodeid;
3370
3371 len = receive_extralen(ms);
3372
3373 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3374 if (dir_nodeid != dlm_our_nodeid()) {
3375 log_error(ls, "remove dir entry dir_nodeid %d from %d",
3376 dir_nodeid, from_nodeid);
3377 return;
3378 }
3379
3380 dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len);
3381}
3382
8499137d
DT		 3383static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
3384{
3385 do_purge(ls, ms->m_nodeid, ms->m_pid);
3386}
3387
e7fd4179
DT		 3388static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
3389{
3390 struct dlm_lkb *lkb;
3391 struct dlm_rsb *r;
ef0c2bb0 3392 int error, mstype, result;
e7fd4179
DT		 3393
3394 error = find_lkb(ls, ms->m_remid, &lkb);
3395 if (error) {
c54e04b0
DT		 3396 log_debug(ls, "receive_request_reply from %d no lkb %x",
3397 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3398 return;
3399 }
e7fd4179 3400
e7fd4179
DT		 3401 r = lkb->lkb_resource;
3402 hold_rsb(r);
3403 lock_rsb(r);
3404
c54e04b0
DT		 3405 error = validate_message(lkb, ms);
3406 if (error)
3407 goto out;
3408
ef0c2bb0
DT		 3409 mstype = lkb->lkb_wait_type;
3410 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
3411 if (error)
3412 goto out;
3413
e7fd4179
DT		 3414 /* Optimization: the dir node was also the master, so it took our
3415 lookup as a request and sent request reply instead of lookup reply */
3416 if (mstype == DLM_MSG_LOOKUP) {
3417 r->res_nodeid = ms->m_header.h_nodeid;
3418 lkb->lkb_nodeid = r->res_nodeid;
3419 }
3420
ef0c2bb0
DT		 3421 /* this is the value returned from do_request() on the master */
3422 result = ms->m_result;
3423
3424 switch (result) {
e7fd4179 3425 case -EAGAIN:
ef0c2bb0 3426 /* request would block (be queued) on remote master */
e7fd4179
DT		 3427 queue_cast(r, lkb, -EAGAIN);
3428 confirm_master(r, -EAGAIN);
ef0c2bb0 3429 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 3430 break;
3431
3432 case -EINPROGRESS:
3433 case 0:
3434 /* request was queued or granted on remote master */
3435 receive_flags_reply(lkb, ms);
3436 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 3437 if (is_altmode(lkb))
3438 munge_altmode(lkb, ms);
3ae1acf9 3439 if (result) {
e7fd4179 3440 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 3441 add_timeout(lkb);
3442 } else {
e7fd4179
DT		 3443 grant_lock_pc(r, lkb, ms);
3444 queue_cast(r, lkb, 0);
3445 }
ef0c2bb0 3446 confirm_master(r, result);
e7fd4179
DT		 3447 break;
3448
597d0cae 3449 case -EBADR:
e7fd4179
DT		 3450 case -ENOTBLK:
3451 /* find_rsb failed to find rsb or rsb wasn't master */
ef0c2bb0
DT		 3452 log_debug(ls, "receive_request_reply %x %x master diff %d %d",
3453 lkb->lkb_id, lkb->lkb_flags, r->res_nodeid, result);
e7fd4179
DT		 3454 r->res_nodeid = -1;
3455 lkb->lkb_nodeid = -1;
ef0c2bb0
DT		 3456
3457 if (is_overlap(lkb)) {
3458 /* we'll ignore error in cancel/unlock reply */
3459 queue_cast_overlap(r, lkb);
aec64e1b 3460 confirm_master(r, result);
ef0c2bb0
DT		 3461 unhold_lkb(lkb); /* undoes create_lkb() */
3462 } else
3463 _request_lock(r, lkb);
e7fd4179
DT		 3464 break;
3465
3466 default:
ef0c2bb0
DT		 3467 log_error(ls, "receive_request_reply %x error %d",
3468 lkb->lkb_id, result);
e7fd4179
DT		 3469 }
3470
ef0c2bb0
DT		 3471 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
3472 log_debug(ls, "receive_request_reply %x result %d unlock",
3473 lkb->lkb_id, result);
3474 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3475 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3476 send_unlock(r, lkb);
3477 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
3478 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
3479 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3480 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3481 send_cancel(r, lkb);
3482 } else {
3483 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3484 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3485 }
3486 out:
e7fd4179
DT		 3487 unlock_rsb(r);
3488 put_rsb(r);
b3f58d8f 3489 dlm_put_lkb(lkb);
e7fd4179
DT		 3490}
3491
3492static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3493 struct dlm_message *ms)
3494{
e7fd4179 3495 /* this is the value returned from do_convert() on the master */
ef0c2bb0 3496 switch (ms->m_result) {
e7fd4179
DT		 3497 case -EAGAIN:
3498 /* convert would block (be queued) on remote master */
3499 queue_cast(r, lkb, -EAGAIN);
3500 break;
3501
c85d65e9
DT		 3502 case -EDEADLK:
3503 receive_flags_reply(lkb, ms);
3504 revert_lock_pc(r, lkb);
3505 queue_cast(r, lkb, -EDEADLK);
3506 break;
3507
e7fd4179
DT		 3508 case -EINPROGRESS:
3509 /* convert was queued on remote master */
7d3c1feb
DT		 3510 receive_flags_reply(lkb, ms);
3511 if (is_demoted(lkb))
3512 munge_demoted(lkb, ms);
e7fd4179
DT		 3513 del_lkb(r, lkb);
3514 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3515 add_timeout(lkb);
e7fd4179
DT		 3516 break;
3517
3518 case 0:
3519 /* convert was granted on remote master */
3520 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 3521 if (is_demoted(lkb))
3522 munge_demoted(lkb, ms);
e7fd4179
DT		 3523 grant_lock_pc(r, lkb, ms);
3524 queue_cast(r, lkb, 0);
3525 break;
3526
3527 default:
ef0c2bb0
DT		 3528 log_error(r->res_ls, "receive_convert_reply %x error %d",
3529 lkb->lkb_id, ms->m_result);
e7fd4179
DT		 3530 }
3531}
3532
3533static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3534{
3535 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3536 int error;
e7fd4179
DT		 3537
3538 hold_rsb(r);
3539 lock_rsb(r);
3540
c54e04b0
DT		 3541 error = validate_message(lkb, ms);
3542 if (error)
3543 goto out;
3544
ef0c2bb0
DT		 3545 /* stub reply can happen with waiters_mutex held */
3546 error = remove_from_waiters_ms(lkb, ms);
3547 if (error)
3548 goto out;
e7fd4179 3549
ef0c2bb0
DT		 3550 __receive_convert_reply(r, lkb, ms);
3551 out:
e7fd4179
DT		 3552 unlock_rsb(r);
3553 put_rsb(r);
3554}
3555
3556static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
3557{
3558 struct dlm_lkb *lkb;
3559 int error;
3560
3561 error = find_lkb(ls, ms->m_remid, &lkb);
3562 if (error) {
c54e04b0
DT		 3563 log_debug(ls, "receive_convert_reply from %d no lkb %x",
3564 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3565 return;
3566 }
e7fd4179 3567
e7fd4179 3568 _receive_convert_reply(lkb, ms);
b3f58d8f 3569 dlm_put_lkb(lkb);
e7fd4179
DT		 3570}
3571
3572static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3573{
3574 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3575 int error;
e7fd4179
DT		 3576
3577 hold_rsb(r);
3578 lock_rsb(r);
3579
c54e04b0
DT		 3580 error = validate_message(lkb, ms);
3581 if (error)
3582 goto out;
3583
ef0c2bb0
DT		 3584 /* stub reply can happen with waiters_mutex held */
3585 error = remove_from_waiters_ms(lkb, ms);
3586 if (error)
3587 goto out;
3588
e7fd4179
DT		 3589 /* this is the value returned from do_unlock() on the master */
3590
ef0c2bb0 3591 switch (ms->m_result) {
e7fd4179
DT		 3592 case -DLM_EUNLOCK:
3593 receive_flags_reply(lkb, ms);
3594 remove_lock_pc(r, lkb);
3595 queue_cast(r, lkb, -DLM_EUNLOCK);
3596 break;
ef0c2bb0
DT		 3597 case -ENOENT:
3598 break;
e7fd4179 3599 default:
ef0c2bb0
DT		 3600 log_error(r->res_ls, "receive_unlock_reply %x error %d",
3601 lkb->lkb_id, ms->m_result);
e7fd4179 3602 }
ef0c2bb0 3603 out:
e7fd4179
DT		 3604 unlock_rsb(r);
3605 put_rsb(r);
3606}
3607
3608static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
3609{
3610 struct dlm_lkb *lkb;
3611 int error;
3612
3613 error = find_lkb(ls, ms->m_remid, &lkb);
3614 if (error) {
c54e04b0
DT		 3615 log_debug(ls, "receive_unlock_reply from %d no lkb %x",
3616 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3617 return;
3618 }
e7fd4179 3619
e7fd4179 3620 _receive_unlock_reply(lkb, ms);
b3f58d8f 3621 dlm_put_lkb(lkb);
e7fd4179
DT		 3622}
3623
3624static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3625{
3626 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3627 int error;
e7fd4179
DT		 3628
3629 hold_rsb(r);
3630 lock_rsb(r);
3631
c54e04b0
DT		 3632 error = validate_message(lkb, ms);
3633 if (error)
3634 goto out;
3635
ef0c2bb0
DT		 3636 /* stub reply can happen with waiters_mutex held */
3637 error = remove_from_waiters_ms(lkb, ms);
3638 if (error)
3639 goto out;
3640
e7fd4179
DT		 3641 /* this is the value returned from do_cancel() on the master */
3642
ef0c2bb0 3643 switch (ms->m_result) {
e7fd4179
DT		 3644 case -DLM_ECANCEL:
3645 receive_flags_reply(lkb, ms);
3646 revert_lock_pc(r, lkb);
84d8cd69 3647 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3648 break;
3649 case 0:
e7fd4179
DT		 3650 break;
3651 default:
ef0c2bb0
DT		 3652 log_error(r->res_ls, "receive_cancel_reply %x error %d",
3653 lkb->lkb_id, ms->m_result);
e7fd4179 3654 }
ef0c2bb0 3655 out:
e7fd4179
DT		 3656 unlock_rsb(r);
3657 put_rsb(r);
3658}
3659
3660static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
3661{
3662 struct dlm_lkb *lkb;
3663 int error;
3664
3665 error = find_lkb(ls, ms->m_remid, &lkb);
3666 if (error) {
c54e04b0
DT		 3667 log_debug(ls, "receive_cancel_reply from %d no lkb %x",
3668 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3669 return;
3670 }
e7fd4179 3671
e7fd4179 3672 _receive_cancel_reply(lkb, ms);
b3f58d8f 3673 dlm_put_lkb(lkb);
e7fd4179
DT		 3674}
3675
3676static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
3677{
3678 struct dlm_lkb *lkb;
3679 struct dlm_rsb *r;
3680 int error, ret_nodeid;
3681
3682 error = find_lkb(ls, ms->m_lkid, &lkb);
3683 if (error) {
3684 log_error(ls, "receive_lookup_reply no lkb");
3685 return;
3686 }
3687
ef0c2bb0 3688 /* ms->m_result is the value returned by dlm_dir_lookup on dir node
e7fd4179 3689 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 3690
3691 r = lkb->lkb_resource;
3692 hold_rsb(r);
3693 lock_rsb(r);
3694
ef0c2bb0
DT		 3695 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3696 if (error)
3697 goto out;
3698
e7fd4179
DT		 3699 ret_nodeid = ms->m_nodeid;
3700 if (ret_nodeid == dlm_our_nodeid()) {
3701 r->res_nodeid = 0;
3702 ret_nodeid = 0;
3703 r->res_first_lkid = 0;
3704 } else {
3705 /* set_master() will copy res_nodeid to lkb_nodeid */
3706 r->res_nodeid = ret_nodeid;
3707 }
3708
ef0c2bb0
DT		 3709 if (is_overlap(lkb)) {
3710 log_debug(ls, "receive_lookup_reply %x unlock %x",
3711 lkb->lkb_id, lkb->lkb_flags);
3712 queue_cast_overlap(r, lkb);
3713 unhold_lkb(lkb); /* undoes create_lkb() */
3714 goto out_list;
3715 }
3716
e7fd4179
DT		 3717 _request_lock(r, lkb);
3718
ef0c2bb0 3719 out_list:
e7fd4179
DT		 3720 if (!ret_nodeid)
3721 process_lookup_list(r);
ef0c2bb0 3722 out:
e7fd4179
DT		 3723 unlock_rsb(r);
3724 put_rsb(r);
b3f58d8f 3725 dlm_put_lkb(lkb);
e7fd4179
DT		 3726}
3727
c36258b5 3728static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179 3729{
46b43eed
DT		 3730 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
3731 log_debug(ls, "ignore non-member message %d from %d %x %x %d",
3732 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
3733 ms->m_remid, ms->m_result);
3734 return;
3735 }
3736
e7fd4179
DT		 3737 switch (ms->m_type) {
3738
3739 /* messages sent to a master node */
3740
3741 case DLM_MSG_REQUEST:
3742 receive_request(ls, ms);
3743 break;
3744
3745 case DLM_MSG_CONVERT:
3746 receive_convert(ls, ms);
3747 break;
3748
3749 case DLM_MSG_UNLOCK:
3750 receive_unlock(ls, ms);
3751 break;
3752
3753 case DLM_MSG_CANCEL:
3754 receive_cancel(ls, ms);
3755 break;
3756
3757 /* messages sent from a master node (replies to above) */
3758
3759 case DLM_MSG_REQUEST_REPLY:
3760 receive_request_reply(ls, ms);
3761 break;
3762
3763 case DLM_MSG_CONVERT_REPLY:
3764 receive_convert_reply(ls, ms);
3765 break;
3766
3767 case DLM_MSG_UNLOCK_REPLY:
3768 receive_unlock_reply(ls, ms);
3769 break;
3770
3771 case DLM_MSG_CANCEL_REPLY:
3772 receive_cancel_reply(ls, ms);
3773 break;
3774
3775 /* messages sent from a master node (only two types of async msg) */
3776
3777 case DLM_MSG_GRANT:
3778 receive_grant(ls, ms);
3779 break;
3780
3781 case DLM_MSG_BAST:
3782 receive_bast(ls, ms);
3783 break;
3784
3785 /* messages sent to a dir node */
3786
3787 case DLM_MSG_LOOKUP:
3788 receive_lookup(ls, ms);
3789 break;
3790
3791 case DLM_MSG_REMOVE:
3792 receive_remove(ls, ms);
3793 break;
3794
3795 /* messages sent from a dir node (remove has no reply) */
3796
3797 case DLM_MSG_LOOKUP_REPLY:
3798 receive_lookup_reply(ls, ms);
3799 break;
3800
8499137d
DT		 3801 /* other messages */
3802
3803 case DLM_MSG_PURGE:
3804 receive_purge(ls, ms);
3805 break;
3806
e7fd4179
DT		 3807 default:
3808 log_error(ls, "unknown message type %d", ms->m_type);
3809 }
3810
e7fd4179 3811 dlm_astd_wake();
e7fd4179
DT		 3812}
3813
c36258b5
DT		 3814/* If the lockspace is in recovery mode (locking stopped), then normal
3815 messages are saved on the requestqueue for processing after recovery is
3816 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
3817 messages off the requestqueue before we process new ones. This occurs right
3818 after recovery completes when we transition from saving all messages on
3819 requestqueue, to processing all the saved messages, to processing new
3820 messages as they arrive. */
e7fd4179 3821
c36258b5
DT		 3822static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
3823 int nodeid)
3824{
3825 if (dlm_locking_stopped(ls)) {
8b0d8e03 3826 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 3827 } else {
3828 dlm_wait_requestqueue(ls);
3829 _receive_message(ls, ms);
3830 }
3831}
3832
3833/* This is called by dlm_recoverd to process messages that were saved on
3834 the requestqueue. */
3835
3836void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms)
3837{
3838 _receive_message(ls, ms);
3839}
3840
3841/* This is called by the midcomms layer when something is received for
3842 the lockspace. It could be either a MSG (normal message sent as part of
3843 standard locking activity) or an RCOM (recovery message sent as part of
3844 lockspace recovery). */
3845
eef7d739 3846void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 3847{
eef7d739 3848 struct dlm_header *hd = &p->header;
c36258b5
DT		 3849 struct dlm_ls *ls;
3850 int type = 0;
3851
3852 switch (hd->h_cmd) {
3853 case DLM_MSG:
eef7d739
AV		 3854 dlm_message_in(&p->message);
3855 type = p->message.m_type;
c36258b5
DT		 3856 break;
3857 case DLM_RCOM:
eef7d739
AV		 3858 dlm_rcom_in(&p->rcom);
3859 type = p->rcom.rc_type;
c36258b5
DT		 3860 break;
3861 default:
3862 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
3863 return;
3864 }
3865
3866 if (hd->h_nodeid != nodeid) {
3867 log_print("invalid h_nodeid %d from %d lockspace %x",
3868 hd->h_nodeid, nodeid, hd->h_lockspace);
3869 return;
3870 }
3871
3872 ls = dlm_find_lockspace_global(hd->h_lockspace);
3873 if (!ls) {
594199eb
DT		 3874 if (dlm_config.ci_log_debug)
3875 log_print("invalid lockspace %x from %d cmd %d type %d",
3876 hd->h_lockspace, nodeid, hd->h_cmd, type);
c36258b5
DT		 3877
3878 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 3879 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 3880 return;
3881 }
3882
3883 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
3884 be inactive (in this ls) before transitioning to recovery mode */
3885
3886 down_read(&ls->ls_recv_active);
3887 if (hd->h_cmd == DLM_MSG)
eef7d739 3888 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 3889 else
eef7d739 3890 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 3891 up_read(&ls->ls_recv_active);
3892
3893 dlm_put_lockspace(ls);
3894}
e7fd4179
DT		 3895
3896static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb)
3897{
3898 if (middle_conversion(lkb)) {
3899 hold_lkb(lkb);
ef0c2bb0 3900 ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179 3901 ls->ls_stub_ms.m_result = -EINPROGRESS;
075529b5 3902 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 3903 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179
DT		 3904 _receive_convert_reply(lkb, &ls->ls_stub_ms);
3905
3906 /* Same special case as in receive_rcom_lock_args() */
3907 lkb->lkb_grmode = DLM_LOCK_IV;
3908 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
3909 unhold_lkb(lkb);
3910
3911 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
3912 lkb->lkb_flags |= DLM_IFL_RESEND;
3913 }
3914
3915 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
3916 conversions are async; there's no reply from the remote master */
3917}
3918
3919/* A waiting lkb needs recovery if the master node has failed, or
3920 the master node is changing (only when no directory is used) */
3921
3922static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb)
3923{
3924 if (dlm_is_removed(ls, lkb->lkb_nodeid))
3925 return 1;
3926
3927 if (!dlm_no_directory(ls))
3928 return 0;
3929
3930 if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid)
3931 return 1;
3932
3933 return 0;
3934}
3935
3936/* Recovery for locks that are waiting for replies from nodes that are now
3937 gone. We can just complete unlocks and cancels by faking a reply from the
3938 dead node. Requests and up-conversions we flag to be resent after
3939 recovery. Down-conversions can just be completed with a fake reply like
3940 unlocks. Conversions between PR and CW need special attention. */
3941
3942void dlm_recover_waiters_pre(struct dlm_ls *ls)
3943{
3944 struct dlm_lkb *lkb, *safe;
601342ce 3945 int wait_type, stub_unlock_result, stub_cancel_result;
e7fd4179 3946
90135925 3947 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 3948
3949 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
3950 log_debug(ls, "pre recover waiter lkid %x type %d flags %x",
3951 lkb->lkb_id, lkb->lkb_wait_type, lkb->lkb_flags);
3952
3953 /* all outstanding lookups, regardless of destination will be
3954 resent after recovery is done */
3955
3956 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
3957 lkb->lkb_flags |= DLM_IFL_RESEND;
3958 continue;
3959 }
3960
3961 if (!waiter_needs_recovery(ls, lkb))
3962 continue;
3963
601342ce
DT		 3964 wait_type = lkb->lkb_wait_type;
3965 stub_unlock_result = -DLM_EUNLOCK;
3966 stub_cancel_result = -DLM_ECANCEL;
3967
3968 /* Main reply may have been received leaving a zero wait_type,
3969 but a reply for the overlapping op may not have been
3970 received. In that case we need to fake the appropriate
3971 reply for the overlap op. */
3972
3973 if (!wait_type) {
3974 if (is_overlap_cancel(lkb)) {
3975 wait_type = DLM_MSG_CANCEL;
3976 if (lkb->lkb_grmode == DLM_LOCK_IV)
3977 stub_cancel_result = 0;
3978 }
3979 if (is_overlap_unlock(lkb)) {
3980 wait_type = DLM_MSG_UNLOCK;
3981 if (lkb->lkb_grmode == DLM_LOCK_IV)
3982 stub_unlock_result = -ENOENT;
3983 }
3984
3985 log_debug(ls, "rwpre overlap %x %x %d %d %d",
3986 lkb->lkb_id, lkb->lkb_flags, wait_type,
3987 stub_cancel_result, stub_unlock_result);
3988 }
3989
3990 switch (wait_type) {
e7fd4179
DT		 3991
3992 case DLM_MSG_REQUEST:
3993 lkb->lkb_flags |= DLM_IFL_RESEND;
3994 break;
3995
3996 case DLM_MSG_CONVERT:
3997 recover_convert_waiter(ls, lkb);
3998 break;
3999
4000 case DLM_MSG_UNLOCK:
4001 hold_lkb(lkb);
ef0c2bb0 4002 ls->ls_stub_ms.m_type = DLM_MSG_UNLOCK_REPLY;
601342ce 4003 ls->ls_stub_ms.m_result = stub_unlock_result;
075529b5 4004 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 4005 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179 4006 _receive_unlock_reply(lkb, &ls->ls_stub_ms);
b3f58d8f 4007 dlm_put_lkb(lkb);
e7fd4179
DT		 4008 break;
4009
4010 case DLM_MSG_CANCEL:
4011 hold_lkb(lkb);
ef0c2bb0 4012 ls->ls_stub_ms.m_type = DLM_MSG_CANCEL_REPLY;
601342ce 4013 ls->ls_stub_ms.m_result = stub_cancel_result;
075529b5 4014 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 4015 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179 4016 _receive_cancel_reply(lkb, &ls->ls_stub_ms);
b3f58d8f 4017 dlm_put_lkb(lkb);
e7fd4179
DT		 4018 break;
4019
4020 default:
601342ce
DT		 4021 log_error(ls, "invalid lkb wait_type %d %d",
4022 lkb->lkb_wait_type, wait_type);
e7fd4179 4023 }
81456807 4024 schedule();
e7fd4179 4025 }
90135925 4026 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4027}
4028
ef0c2bb0 4029static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 4030{
4031 struct dlm_lkb *lkb;
ef0c2bb0 4032 int found = 0;
e7fd4179 4033
90135925 4034 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4035 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
4036 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 4037 hold_lkb(lkb);
4038 found = 1;
e7fd4179
DT		 4039 break;
4040 }
4041 }
90135925 4042 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 4043
ef0c2bb0 4044 if (!found)
e7fd4179 4045 lkb = NULL;
ef0c2bb0 4046 return lkb;
e7fd4179
DT		 4047}
4048
4049/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
4050 master or dir-node for r. Processing the lkb may result in it being placed
4051 back on waiters. */
4052
ef0c2bb0
DT		 4053/* We do this after normal locking has been enabled and any saved messages
4054 (in requestqueue) have been processed. We should be confident that at
4055 this point we won't get or process a reply to any of these waiting
4056 operations. But, new ops may be coming in on the rsbs/locks here from
4057 userspace or remotely. */
4058
4059/* there may have been an overlap unlock/cancel prior to recovery or after
4060 recovery. if before, the lkb may still have a pos wait_count; if after, the
4061 overlap flag would just have been set and nothing new sent. we can be
4062 confident here than any replies to either the initial op or overlap ops
4063 prior to recovery have been received. */
4064
e7fd4179
DT		 4065int dlm_recover_waiters_post(struct dlm_ls *ls)
4066{
4067 struct dlm_lkb *lkb;
4068 struct dlm_rsb *r;
ef0c2bb0 4069 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 4070
4071 while (1) {
4072 if (dlm_locking_stopped(ls)) {
4073 log_debug(ls, "recover_waiters_post aborted");
4074 error = -EINTR;
4075 break;
4076 }
4077
ef0c2bb0
DT		 4078 lkb = find_resend_waiter(ls);
4079 if (!lkb)
e7fd4179
DT		 4080 break;
4081
4082 r = lkb->lkb_resource;
ef0c2bb0
DT		 4083 hold_rsb(r);
4084 lock_rsb(r);
4085
4086 mstype = lkb->lkb_wait_type;
4087 oc = is_overlap_cancel(lkb);
4088 ou = is_overlap_unlock(lkb);
4089 err = 0;
e7fd4179
DT		 4090
4091 log_debug(ls, "recover_waiters_post %x type %d flags %x %s",
4092 lkb->lkb_id, mstype, lkb->lkb_flags, r->res_name);
4093
ef0c2bb0
DT		 4094 /* At this point we assume that we won't get a reply to any
4095 previous op or overlap op on this lock. First, do a big
4096 remove_from_waiters() for all previous ops. */
4097
4098 lkb->lkb_flags &= ~DLM_IFL_RESEND;
4099 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4100 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4101 lkb->lkb_wait_type = 0;
4102 lkb->lkb_wait_count = 0;
4103 mutex_lock(&ls->ls_waiters_mutex);
4104 list_del_init(&lkb->lkb_wait_reply);
4105 mutex_unlock(&ls->ls_waiters_mutex);
4106 unhold_lkb(lkb); /* for waiters list */
4107
4108 if (oc || ou) {
4109 /* do an unlock or cancel instead of resending */
4110 switch (mstype) {
4111 case DLM_MSG_LOOKUP:
4112 case DLM_MSG_REQUEST:
4113 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
4114 -DLM_ECANCEL);
4115 unhold_lkb(lkb); /* undoes create_lkb() */
4116 break;
4117 case DLM_MSG_CONVERT:
4118 if (oc) {
4119 queue_cast(r, lkb, -DLM_ECANCEL);
4120 } else {
4121 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
4122 _unlock_lock(r, lkb);
4123 }
4124 break;
4125 default:
4126 err = 1;
4127 }
4128 } else {
4129 switch (mstype) {
4130 case DLM_MSG_LOOKUP:
4131 case DLM_MSG_REQUEST:
4132 _request_lock(r, lkb);
4133 if (is_master(r))
4134 confirm_master(r, 0);
4135 break;
4136 case DLM_MSG_CONVERT:
4137 _convert_lock(r, lkb);
4138 break;
4139 default:
4140 err = 1;
4141 }
e7fd4179 4142 }
ef0c2bb0
DT		 4143
4144 if (err)
4145 log_error(ls, "recover_waiters_post %x %d %x %d %d",
4146 lkb->lkb_id, mstype, lkb->lkb_flags, oc, ou);
4147 unlock_rsb(r);
4148 put_rsb(r);
4149 dlm_put_lkb(lkb);
e7fd4179
DT		 4150 }
4151
4152 return error;
4153}
4154
4155static void purge_queue(struct dlm_rsb *r, struct list_head *queue,
4156 int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb))
4157{
4158 struct dlm_ls *ls = r->res_ls;
4159 struct dlm_lkb *lkb, *safe;
4160
4161 list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) {
4162 if (test(ls, lkb)) {
97a35d1e 4163 rsb_set_flag(r, RSB_LOCKS_PURGED);
e7fd4179
DT		 4164 del_lkb(r, lkb);
4165 /* this put should free the lkb */
b3f58d8f 4166 if (!dlm_put_lkb(lkb))
e7fd4179
DT		 4167 log_error(ls, "purged lkb not released");
4168 }
4169 }
4170}
4171
4172static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4173{
4174 return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid));
4175}
4176
4177static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4178{
4179 return is_master_copy(lkb);
4180}
4181
4182static void purge_dead_locks(struct dlm_rsb *r)
4183{
4184 purge_queue(r, &r->res_grantqueue, &purge_dead_test);
4185 purge_queue(r, &r->res_convertqueue, &purge_dead_test);
4186 purge_queue(r, &r->res_waitqueue, &purge_dead_test);
4187}
4188
4189void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
4190{
4191 purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test);
4192 purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test);
4193 purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test);
4194}
4195
4196/* Get rid of locks held by nodes that are gone. */
4197
4198int dlm_purge_locks(struct dlm_ls *ls)
4199{
4200 struct dlm_rsb *r;
4201
4202 log_debug(ls, "dlm_purge_locks");
4203
4204 down_write(&ls->ls_root_sem);
4205 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
4206 hold_rsb(r);
4207 lock_rsb(r);
4208 if (is_master(r))
4209 purge_dead_locks(r);
4210 unlock_rsb(r);
4211 unhold_rsb(r);
4212
4213 schedule();
4214 }
4215 up_write(&ls->ls_root_sem);
4216
4217 return 0;
4218}
4219
97a35d1e
DT		 4220static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
4221{
4222 struct dlm_rsb *r, *r_ret = NULL;
4223
4224 read_lock(&ls->ls_rsbtbl[bucket].lock);
4225 list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list, res_hashchain) {
4226 if (!rsb_flag(r, RSB_LOCKS_PURGED))
4227 continue;
4228 hold_rsb(r);
4229 rsb_clear_flag(r, RSB_LOCKS_PURGED);
4230 r_ret = r;
4231 break;
4232 }
4233 read_unlock(&ls->ls_rsbtbl[bucket].lock);
4234 return r_ret;
4235}
4236
4237void dlm_grant_after_purge(struct dlm_ls *ls)
e7fd4179
DT		 4238{
4239 struct dlm_rsb *r;
2b4e926a 4240 int bucket = 0;
e7fd4179 4241
2b4e926a
DT		 4242 while (1) {
4243 r = find_purged_rsb(ls, bucket);
4244 if (!r) {
4245 if (bucket == ls->ls_rsbtbl_size - 1)
4246 break;
4247 bucket++;
97a35d1e 4248 continue;
2b4e926a 4249 }
97a35d1e
DT		 4250 lock_rsb(r);
4251 if (is_master(r)) {
4252 grant_pending_locks(r);
4253 confirm_master(r, 0);
e7fd4179 4254 }
97a35d1e
DT		 4255 unlock_rsb(r);
4256 put_rsb(r);
2b4e926a 4257 schedule();
e7fd4179 4258 }
e7fd4179
DT		 4259}
4260
4261static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
4262 uint32_t remid)
4263{
4264 struct dlm_lkb *lkb;
4265
4266 list_for_each_entry(lkb, head, lkb_statequeue) {
4267 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
4268 return lkb;
4269 }
4270 return NULL;
4271}
4272
4273static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
4274 uint32_t remid)
4275{
4276 struct dlm_lkb *lkb;
4277
4278 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
4279 if (lkb)
4280 return lkb;
4281 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
4282 if (lkb)
4283 return lkb;
4284 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
4285 if (lkb)
4286 return lkb;
4287 return NULL;
4288}
4289
ae773d0b 4290/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4291static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
4292 struct dlm_rsb *r, struct dlm_rcom *rc)
4293{
4294 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 4295
4296 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 4297 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
4298 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
4299 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
4300 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 4301 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 4302 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 4303 lkb->lkb_rqmode = rl->rl_rqmode;
4304 lkb->lkb_grmode = rl->rl_grmode;
4305 /* don't set lkb_status because add_lkb wants to itself */
4306
e5dae548
DT		 4307 lkb->lkb_bastfn = (rl->rl_asts & AST_BAST) ? &fake_bastfn : NULL;
4308 lkb->lkb_astfn = (rl->rl_asts & AST_COMP) ? &fake_astfn : NULL;
e7fd4179 4309
e7fd4179 4310 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 4311 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
4312 sizeof(struct rcom_lock);
4313 if (lvblen > ls->ls_lvblen)
4314 return -EINVAL;
52bda2b5 4315 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 4316 if (!lkb->lkb_lvbptr)
4317 return -ENOMEM;
e7fd4179
DT		 4318 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
4319 }
4320
4321 /* Conversions between PR and CW (middle modes) need special handling.
4322 The real granted mode of these converting locks cannot be determined
4323 until all locks have been rebuilt on the rsb (recover_conversion) */
4324
163a1859
AV		 4325 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
4326 middle_conversion(lkb)) {
e7fd4179
DT		 4327 rl->rl_status = DLM_LKSTS_CONVERT;
4328 lkb->lkb_grmode = DLM_LOCK_IV;
4329 rsb_set_flag(r, RSB_RECOVER_CONVERT);
4330 }
4331
4332 return 0;
4333}
4334
4335/* This lkb may have been recovered in a previous aborted recovery so we need
4336 to check if the rsb already has an lkb with the given remote nodeid/lkid.
4337 If so we just send back a standard reply. If not, we create a new lkb with
4338 the given values and send back our lkid. We send back our lkid by sending
4339 back the rcom_lock struct we got but with the remid field filled in. */
4340
ae773d0b 4341/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4342int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4343{
4344 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4345 struct dlm_rsb *r;
4346 struct dlm_lkb *lkb;
4347 int error;
4348
4349 if (rl->rl_parent_lkid) {
4350 error = -EOPNOTSUPP;
4351 goto out;
4352 }
4353
163a1859
AV		 4354 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
4355 R_MASTER, &r);
e7fd4179
DT		 4356 if (error)
4357 goto out;
4358
4359 lock_rsb(r);
4360
163a1859 4361 lkb = search_remid(r, rc->rc_header.h_nodeid, le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4362 if (lkb) {
4363 error = -EEXIST;
4364 goto out_remid;
4365 }
4366
4367 error = create_lkb(ls, &lkb);
4368 if (error)
4369 goto out_unlock;
4370
4371 error = receive_rcom_lock_args(ls, lkb, r, rc);
4372 if (error) {
b3f58d8f 4373 __put_lkb(ls, lkb);
e7fd4179
DT		 4374 goto out_unlock;
4375 }
4376
4377 attach_lkb(r, lkb);
4378 add_lkb(r, lkb, rl->rl_status);
4379 error = 0;
4380
4381 out_remid:
4382 /* this is the new value returned to the lock holder for
4383 saving in its process-copy lkb */
163a1859 4384 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179
DT		 4385
4386 out_unlock:
4387 unlock_rsb(r);
4388 put_rsb(r);
4389 out:
4390 if (error)
163a1859
AV		 4391 log_debug(ls, "recover_master_copy %d %x", error,
4392 le32_to_cpu(rl->rl_lkid));
4393 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 4394 return error;
4395}
4396
ae773d0b 4397/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4398int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4399{
4400 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4401 struct dlm_rsb *r;
4402 struct dlm_lkb *lkb;
4403 int error;
4404
163a1859 4405 error = find_lkb(ls, le32_to_cpu(rl->rl_lkid), &lkb);
e7fd4179 4406 if (error) {
163a1859
AV		 4407 log_error(ls, "recover_process_copy no lkid %x",
4408 le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4409 return error;
4410 }
4411
4412 DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
4413
163a1859 4414 error = le32_to_cpu(rl->rl_result);
e7fd4179
DT		 4415
4416 r = lkb->lkb_resource;
4417 hold_rsb(r);
4418 lock_rsb(r);
4419
4420 switch (error) {
dc200a88
DT		 4421 case -EBADR:
4422 /* There's a chance the new master received our lock before
4423 dlm_recover_master_reply(), this wouldn't happen if we did
4424 a barrier between recover_masters and recover_locks. */
4425 log_debug(ls, "master copy not ready %x r %lx %s", lkb->lkb_id,
4426 (unsigned long)r, r->res_name);
4427 dlm_send_rcom_lock(r, lkb);
4428 goto out;
e7fd4179
DT		 4429 case -EEXIST:
4430 log_debug(ls, "master copy exists %x", lkb->lkb_id);
4431 /* fall through */
4432 case 0:
163a1859 4433 lkb->lkb_remid = le32_to_cpu(rl->rl_remid);
e7fd4179
DT		 4434 break;
4435 default:
4436 log_error(ls, "dlm_recover_process_copy unknown error %d %x",
4437 error, lkb->lkb_id);
4438 }
4439
4440 /* an ack for dlm_recover_locks() which waits for replies from
4441 all the locks it sends to new masters */
4442 dlm_recovered_lock(r);
dc200a88 4443 out:
e7fd4179
DT		 4444 unlock_rsb(r);
4445 put_rsb(r);
b3f58d8f 4446 dlm_put_lkb(lkb);
e7fd4179
DT		 4447
4448 return 0;
4449}
4450
597d0cae
DT		 4451int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
4452 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 4453 unsigned long timeout_cs)
597d0cae
DT		 4454{
4455 struct dlm_lkb *lkb;
4456 struct dlm_args args;
4457 int error;
4458
85e86edf 4459 dlm_lock_recovery(ls);
597d0cae
DT		 4460
4461 error = create_lkb(ls, &lkb);
4462 if (error) {
4463 kfree(ua);
4464 goto out;
4465 }
4466
4467 if (flags & DLM_LKF_VALBLK) {
62a0f623 4468 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_KERNEL);
597d0cae
DT		 4469 if (!ua->lksb.sb_lvbptr) {
4470 kfree(ua);
4471 __put_lkb(ls, lkb);
4472 error = -ENOMEM;
4473 goto out;
4474 }
4475 }
4476
52bda2b5 4477 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 4478 When DLM_IFL_USER is set, the dlm knows that this is a userspace
4479 lock and that lkb_astparam is the dlm_user_args structure. */
4480
d7db923e 4481 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 4482 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 4483 lkb->lkb_flags |= DLM_IFL_USER;
4484 ua->old_mode = DLM_LOCK_IV;
4485
4486 if (error) {
4487 __put_lkb(ls, lkb);
4488 goto out;
4489 }
4490
4491 error = request_lock(ls, lkb, name, namelen, &args);
4492
4493 switch (error) {
4494 case 0:
4495 break;
4496 case -EINPROGRESS:
4497 error = 0;
4498 break;
4499 case -EAGAIN:
4500 error = 0;
4501 /* fall through */
4502 default:
4503 __put_lkb(ls, lkb);
4504 goto out;
4505 }
4506
4507 /* add this new lkb to the per-process list of locks */
4508 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 4509 hold_lkb(lkb);
597d0cae
DT		 4510 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
4511 spin_unlock(&ua->proc->locks_spin);
4512 out:
85e86edf 4513 dlm_unlock_recovery(ls);
597d0cae
DT		 4514 return error;
4515}
4516
4517int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 4518 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
4519 unsigned long timeout_cs)
597d0cae
DT		 4520{
4521 struct dlm_lkb *lkb;
4522 struct dlm_args args;
4523 struct dlm_user_args *ua;
4524 int error;
4525
85e86edf 4526 dlm_lock_recovery(ls);
597d0cae
DT		 4527
4528 error = find_lkb(ls, lkid, &lkb);
4529 if (error)
4530 goto out;
4531
4532 /* user can change the params on its lock when it converts it, or
4533 add an lvb that didn't exist before */
4534
d292c0cc 4535 ua = lkb->lkb_ua;
597d0cae
DT		 4536
4537 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
62a0f623 4538 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_KERNEL);
597d0cae
DT		 4539 if (!ua->lksb.sb_lvbptr) {
4540 error = -ENOMEM;
4541 goto out_put;
4542 }
4543 }
4544 if (lvb_in && ua->lksb.sb_lvbptr)
4545 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
4546
d7db923e 4547 ua->xid = ua_tmp->xid;
597d0cae
DT		 4548 ua->castparam = ua_tmp->castparam;
4549 ua->castaddr = ua_tmp->castaddr;
4550 ua->bastparam = ua_tmp->bastparam;
4551 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 4552 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4553 ua->old_mode = lkb->lkb_grmode;
4554
d7db923e 4555 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 4556 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 4557 if (error)
4558 goto out_put;
4559
4560 error = convert_lock(ls, lkb, &args);
4561
c85d65e9 4562 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 4563 error = 0;
4564 out_put:
4565 dlm_put_lkb(lkb);
4566 out:
85e86edf 4567 dlm_unlock_recovery(ls);
597d0cae
DT		 4568 kfree(ua_tmp);
4569 return error;
4570}
4571
4572int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4573 uint32_t flags, uint32_t lkid, char *lvb_in)
4574{
4575 struct dlm_lkb *lkb;
4576 struct dlm_args args;
4577 struct dlm_user_args *ua;
4578 int error;
4579
85e86edf 4580 dlm_lock_recovery(ls);
597d0cae
DT		 4581
4582 error = find_lkb(ls, lkid, &lkb);
4583 if (error)
4584 goto out;
4585
d292c0cc 4586 ua = lkb->lkb_ua;
597d0cae
DT		 4587
4588 if (lvb_in && ua->lksb.sb_lvbptr)
4589 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 4590 if (ua_tmp->castparam)
4591 ua->castparam = ua_tmp->castparam;
cc346d55 4592 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4593
4594 error = set_unlock_args(flags, ua, &args);
4595 if (error)
4596 goto out_put;
4597
4598 error = unlock_lock(ls, lkb, &args);
4599
4600 if (error == -DLM_EUNLOCK)
4601 error = 0;
ef0c2bb0
DT		 4602 /* from validate_unlock_args() */
4603 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
4604 error = 0;
597d0cae
DT		 4605 if (error)
4606 goto out_put;
4607
4608 spin_lock(&ua->proc->locks_spin);
a1bc86e6
DT		 4609 /* dlm_user_add_ast() may have already taken lkb off the proc list */
4610 if (!list_empty(&lkb->lkb_ownqueue))
4611 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 4612 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 4613 out_put:
4614 dlm_put_lkb(lkb);
4615 out:
85e86edf 4616 dlm_unlock_recovery(ls);
ef0c2bb0 4617 kfree(ua_tmp);
597d0cae
DT		 4618 return error;
4619}
4620
4621int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4622 uint32_t flags, uint32_t lkid)
4623{
4624 struct dlm_lkb *lkb;
4625 struct dlm_args args;
4626 struct dlm_user_args *ua;
4627 int error;
4628
85e86edf 4629 dlm_lock_recovery(ls);
597d0cae
DT		 4630
4631 error = find_lkb(ls, lkid, &lkb);
4632 if (error)
4633 goto out;
4634
d292c0cc 4635 ua = lkb->lkb_ua;
b434eda6
PC		 4636 if (ua_tmp->castparam)
4637 ua->castparam = ua_tmp->castparam;
c059f70e 4638 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4639
4640 error = set_unlock_args(flags, ua, &args);
4641 if (error)
4642 goto out_put;
4643
4644 error = cancel_lock(ls, lkb, &args);
4645
4646 if (error == -DLM_ECANCEL)
4647 error = 0;
ef0c2bb0
DT		 4648 /* from validate_unlock_args() */
4649 if (error == -EBUSY)
4650 error = 0;
597d0cae
DT		 4651 out_put:
4652 dlm_put_lkb(lkb);
4653 out:
85e86edf 4654 dlm_unlock_recovery(ls);
ef0c2bb0 4655 kfree(ua_tmp);
597d0cae
DT		 4656 return error;
4657}
4658
8b4021fa
DT		 4659int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
4660{
4661 struct dlm_lkb *lkb;
4662 struct dlm_args args;
4663 struct dlm_user_args *ua;
4664 struct dlm_rsb *r;
4665 int error;
4666
4667 dlm_lock_recovery(ls);
4668
4669 error = find_lkb(ls, lkid, &lkb);
4670 if (error)
4671 goto out;
4672
d292c0cc 4673 ua = lkb->lkb_ua;
8b4021fa
DT		 4674
4675 error = set_unlock_args(flags, ua, &args);
4676 if (error)
4677 goto out_put;
4678
4679 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
4680
4681 r = lkb->lkb_resource;
4682 hold_rsb(r);
4683 lock_rsb(r);
4684
4685 error = validate_unlock_args(lkb, &args);
4686 if (error)
4687 goto out_r;
4688 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
4689
4690 error = _cancel_lock(r, lkb);
4691 out_r:
4692 unlock_rsb(r);
4693 put_rsb(r);
4694
4695 if (error == -DLM_ECANCEL)
4696 error = 0;
4697 /* from validate_unlock_args() */
4698 if (error == -EBUSY)
4699 error = 0;
4700 out_put:
4701 dlm_put_lkb(lkb);
4702 out:
4703 dlm_unlock_recovery(ls);
4704 return error;
4705}
4706
ef0c2bb0
DT		 4707/* lkb's that are removed from the waiters list by revert are just left on the
4708 orphans list with the granted orphan locks, to be freed by purge */
4709
597d0cae
DT		 4710static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4711{
ef0c2bb0
DT		 4712 struct dlm_args args;
4713 int error;
597d0cae 4714
ef0c2bb0
DT		 4715 hold_lkb(lkb);
4716 mutex_lock(&ls->ls_orphans_mutex);
4717 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
4718 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 4719
d292c0cc 4720 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 4721
4722 error = cancel_lock(ls, lkb, &args);
4723 if (error == -DLM_ECANCEL)
4724 error = 0;
4725 return error;
597d0cae
DT		 4726}
4727
4728/* The force flag allows the unlock to go ahead even if the lkb isn't granted.
4729 Regardless of what rsb queue the lock is on, it's removed and freed. */
4730
4731static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4732{
597d0cae
DT		 4733 struct dlm_args args;
4734 int error;
4735
d292c0cc 4736 set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
597d0cae
DT		 4737
4738 error = unlock_lock(ls, lkb, &args);
4739 if (error == -DLM_EUNLOCK)
4740 error = 0;
4741 return error;
4742}
4743
ef0c2bb0
DT		 4744/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
4745 (which does lock_rsb) due to deadlock with receiving a message that does
4746 lock_rsb followed by dlm_user_add_ast() */
4747
4748static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
4749 struct dlm_user_proc *proc)
4750{
4751 struct dlm_lkb *lkb = NULL;
4752
4753 mutex_lock(&ls->ls_clear_proc_locks);
4754 if (list_empty(&proc->locks))
4755 goto out;
4756
4757 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
4758 list_del_init(&lkb->lkb_ownqueue);
4759
4760 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
4761 lkb->lkb_flags |= DLM_IFL_ORPHAN;
4762 else
4763 lkb->lkb_flags |= DLM_IFL_DEAD;
4764 out:
4765 mutex_unlock(&ls->ls_clear_proc_locks);
4766 return lkb;
4767}
4768
597d0cae
DT		 4769/* The ls_clear_proc_locks mutex protects against dlm_user_add_asts() which
4770 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
4771 which we clear here. */
4772
4773/* proc CLOSING flag is set so no more device_reads should look at proc->asts
4774 list, and no more device_writes should add lkb's to proc->locks list; so we
4775 shouldn't need to take asts_spin or locks_spin here. this assumes that
4776 device reads/writes/closes are serialized -- FIXME: we may need to serialize
4777 them ourself. */
4778
4779void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
4780{
4781 struct dlm_lkb *lkb, *safe;
4782
85e86edf 4783 dlm_lock_recovery(ls);
597d0cae 4784
ef0c2bb0
DT		 4785 while (1) {
4786 lkb = del_proc_lock(ls, proc);
4787 if (!lkb)
4788 break;
84d8cd69 4789 del_timeout(lkb);
ef0c2bb0 4790 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 4791 orphan_proc_lock(ls, lkb);
ef0c2bb0 4792 else
597d0cae 4793 unlock_proc_lock(ls, lkb);
597d0cae
DT		 4794
4795 /* this removes the reference for the proc->locks list
4796 added by dlm_user_request, it may result in the lkb
4797 being freed */
4798
4799 dlm_put_lkb(lkb);
4800 }
a1bc86e6 4801
ef0c2bb0
DT		 4802 mutex_lock(&ls->ls_clear_proc_locks);
4803
a1bc86e6
DT		 4804 /* in-progress unlocks */
4805 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
4806 list_del_init(&lkb->lkb_ownqueue);
4807 lkb->lkb_flags |= DLM_IFL_DEAD;
4808 dlm_put_lkb(lkb);
4809 }
4810
4811 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
8a358ca8 4812 lkb->lkb_ast_type = 0;
a1bc86e6
DT		 4813 list_del(&lkb->lkb_astqueue);
4814 dlm_put_lkb(lkb);
4815 }
4816
597d0cae 4817 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 4818 dlm_unlock_recovery(ls);
597d0cae 4819}
a1bc86e6 4820
8499137d
DT		 4821static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
4822{
4823 struct dlm_lkb *lkb, *safe;
4824
4825 while (1) {
4826 lkb = NULL;
4827 spin_lock(&proc->locks_spin);
4828 if (!list_empty(&proc->locks)) {
4829 lkb = list_entry(proc->locks.next, struct dlm_lkb,
4830 lkb_ownqueue);
4831 list_del_init(&lkb->lkb_ownqueue);
4832 }
4833 spin_unlock(&proc->locks_spin);
4834
4835 if (!lkb)
4836 break;
4837
4838 lkb->lkb_flags |= DLM_IFL_DEAD;
4839 unlock_proc_lock(ls, lkb);
4840 dlm_put_lkb(lkb); /* ref from proc->locks list */
4841 }
4842
4843 spin_lock(&proc->locks_spin);
4844 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
4845 list_del_init(&lkb->lkb_ownqueue);
4846 lkb->lkb_flags |= DLM_IFL_DEAD;
4847 dlm_put_lkb(lkb);
4848 }
4849 spin_unlock(&proc->locks_spin);
4850
4851 spin_lock(&proc->asts_spin);
4852 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
4853 list_del(&lkb->lkb_astqueue);
4854 dlm_put_lkb(lkb);
4855 }
4856 spin_unlock(&proc->asts_spin);
4857}
4858
4859/* pid of 0 means purge all orphans */
4860
4861static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
4862{
4863 struct dlm_lkb *lkb, *safe;
4864
4865 mutex_lock(&ls->ls_orphans_mutex);
4866 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
4867 if (pid && lkb->lkb_ownpid != pid)
4868 continue;
4869 unlock_proc_lock(ls, lkb);
4870 list_del_init(&lkb->lkb_ownqueue);
4871 dlm_put_lkb(lkb);
4872 }
4873 mutex_unlock(&ls->ls_orphans_mutex);
4874}
4875
4876static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
4877{
4878 struct dlm_message *ms;
4879 struct dlm_mhandle *mh;
4880 int error;
4881
4882 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
4883 DLM_MSG_PURGE, &ms, &mh);
4884 if (error)
4885 return error;
4886 ms->m_nodeid = nodeid;
4887 ms->m_pid = pid;
4888
4889 return send_message(mh, ms);
4890}
4891
4892int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
4893 int nodeid, int pid)
4894{
4895 int error = 0;
4896
4897 if (nodeid != dlm_our_nodeid()) {
4898 error = send_purge(ls, nodeid, pid);
4899 } else {
85e86edf 4900 dlm_lock_recovery(ls);
8499137d
DT		 4901 if (pid == current->pid)
4902 purge_proc_locks(ls, proc);
4903 else
4904 do_purge(ls, nodeid, pid);
85e86edf 4905 dlm_unlock_recovery(ls);
8499137d
DT		 4906 }
4907 return error;
4908}
4909
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