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[net-next-2.6.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
fd22a51b 310 dlm_add_ast(lkb, AST_COMP, 0);
e7fd4179
DT		 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{
e3a84ad4
DT		 321 lkb->lkb_time_bast = ktime_get();
322
e7fd4179
DT		 323 if (is_master_copy(lkb))
324 send_bast(r, lkb, rqmode);
fd22a51b
DT		 325 else
326 dlm_add_ast(lkb, AST_BAST, rqmode);
e7fd4179
DT		 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 }
18c60c0a 366 *r_ret = NULL;
597d0cae 367 return -EBADR;
e7fd4179
DT		 368
369 found:
370 if (r->res_nodeid && (flags & R_MASTER))
371 error = -ENOTBLK;
372 *r_ret = r;
373 return error;
374}
375
376static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b,
377 unsigned int flags, struct dlm_rsb **r_ret)
378{
379 struct dlm_rsb *r;
380 int error;
381
382 error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r);
383 if (!error) {
384 kref_get(&r->res_ref);
385 goto out;
386 }
387 error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
388 if (error)
389 goto out;
390
391 list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list);
392
393 if (dlm_no_directory(ls))
394 goto out;
395
396 if (r->res_nodeid == -1) {
397 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
398 r->res_first_lkid = 0;
399 } else if (r->res_nodeid > 0) {
400 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
401 r->res_first_lkid = 0;
402 } else {
403 DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r););
404 DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),);
405 }
406 out:
407 *r_ret = r;
408 return error;
409}
410
411static int search_rsb(struct dlm_ls *ls, char *name, int len, int b,
412 unsigned int flags, struct dlm_rsb **r_ret)
413{
414 int error;
c7be761a 415 spin_lock(&ls->ls_rsbtbl[b].lock);
e7fd4179 416 error = _search_rsb(ls, name, len, b, flags, r_ret);
c7be761a 417 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 418 return error;
419}
420
421/*
422 * Find rsb in rsbtbl and potentially create/add one
423 *
424 * Delaying the release of rsb's has a similar benefit to applications keeping
425 * NL locks on an rsb, but without the guarantee that the cached master value
426 * will still be valid when the rsb is reused. Apps aren't always smart enough
427 * to keep NL locks on an rsb that they may lock again shortly; this can lead
428 * to excessive master lookups and removals if we don't delay the release.
429 *
430 * Searching for an rsb means looking through both the normal list and toss
431 * list. When found on the toss list the rsb is moved to the normal list with
432 * ref count of 1; when found on normal list the ref count is incremented.
433 */
434
435static int find_rsb(struct dlm_ls *ls, char *name, int namelen,
436 unsigned int flags, struct dlm_rsb **r_ret)
437{
a566a6b1 438 struct dlm_rsb *r = NULL, *tmp;
e7fd4179 439 uint32_t hash, bucket;
ef58bcca
AV		 440 int error = -EINVAL;
441
442 if (namelen > DLM_RESNAME_MAXLEN)
443 goto out;
e7fd4179
DT		 444
445 if (dlm_no_directory(ls))
446 flags |= R_CREATE;
447
ef58bcca 448 error = 0;
e7fd4179
DT		 449 hash = jhash(name, namelen, 0);
450 bucket = hash & (ls->ls_rsbtbl_size - 1);
451
452 error = search_rsb(ls, name, namelen, bucket, flags, &r);
453 if (!error)
454 goto out;
455
597d0cae 456 if (error == -EBADR && !(flags & R_CREATE))
e7fd4179
DT		 457 goto out;
458
459 /* the rsb was found but wasn't a master copy */
460 if (error == -ENOTBLK)
461 goto out;
462
463 error = -ENOMEM;
464 r = create_rsb(ls, name, namelen);
465 if (!r)
466 goto out;
467
468 r->res_hash = hash;
469 r->res_bucket = bucket;
470 r->res_nodeid = -1;
471 kref_init(&r->res_ref);
472
473 /* With no directory, the master can be set immediately */
474 if (dlm_no_directory(ls)) {
475 int nodeid = dlm_dir_nodeid(r);
476 if (nodeid == dlm_our_nodeid())
477 nodeid = 0;
478 r->res_nodeid = nodeid;
479 }
480
c7be761a 481 spin_lock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179
DT		 482 error = _search_rsb(ls, name, namelen, bucket, 0, &tmp);
483 if (!error) {
c7be761a 484 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
52bda2b5 485 dlm_free_rsb(r);
e7fd4179
DT		 486 r = tmp;
487 goto out;
488 }
489 list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list);
c7be761a 490 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179
DT		 491 error = 0;
492 out:
493 *r_ret = r;
494 return error;
495}
496
e7fd4179
DT		 497/* This is only called to add a reference when the code already holds
498 a valid reference to the rsb, so there's no need for locking. */
499
500static inline void hold_rsb(struct dlm_rsb *r)
501{
502 kref_get(&r->res_ref);
503}
504
505void dlm_hold_rsb(struct dlm_rsb *r)
506{
507 hold_rsb(r);
508}
509
510static void toss_rsb(struct kref *kref)
511{
512 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
513 struct dlm_ls *ls = r->res_ls;
514
515 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
516 kref_init(&r->res_ref);
517 list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss);
518 r->res_toss_time = jiffies;
519 if (r->res_lvbptr) {
52bda2b5 520 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 521 r->res_lvbptr = NULL;
522 }
523}
524
525/* When all references to the rsb are gone it's transfered to
526 the tossed list for later disposal. */
527
528static void put_rsb(struct dlm_rsb *r)
529{
530 struct dlm_ls *ls = r->res_ls;
531 uint32_t bucket = r->res_bucket;
532
c7be761a 533 spin_lock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179 534 kref_put(&r->res_ref, toss_rsb);
c7be761a 535 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179
DT		 536}
537
538void dlm_put_rsb(struct dlm_rsb *r)
539{
540 put_rsb(r);
541}
542
543/* See comment for unhold_lkb */
544
545static void unhold_rsb(struct dlm_rsb *r)
546{
547 int rv;
548 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 549 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 550}
551
552static void kill_rsb(struct kref *kref)
553{
554 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
555
556 /* All work is done after the return from kref_put() so we
557 can release the write_lock before the remove and free. */
558
a345da3e
DT		 559 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
560 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
561 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
562 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
563 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
564 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 565}
566
567/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
568 The rsb must exist as long as any lkb's for it do. */
569
570static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
571{
572 hold_rsb(r);
573 lkb->lkb_resource = r;
574}
575
576static void detach_lkb(struct dlm_lkb *lkb)
577{
578 if (lkb->lkb_resource) {
579 put_rsb(lkb->lkb_resource);
580 lkb->lkb_resource = NULL;
581 }
582}
583
584static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
585{
586 struct dlm_lkb *lkb, *tmp;
587 uint32_t lkid = 0;
588 uint16_t bucket;
589
52bda2b5 590 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 591 if (!lkb)
592 return -ENOMEM;
593
594 lkb->lkb_nodeid = -1;
595 lkb->lkb_grmode = DLM_LOCK_IV;
596 kref_init(&lkb->lkb_ref);
34e22bed 597 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 598 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 599 INIT_LIST_HEAD(&lkb->lkb_time_list);
e7fd4179
DT		 600
601 get_random_bytes(&bucket, sizeof(bucket));
602 bucket &= (ls->ls_lkbtbl_size - 1);
603
604 write_lock(&ls->ls_lkbtbl[bucket].lock);
605
606 /* counter can roll over so we must verify lkid is not in use */
607
608 while (lkid == 0) {
ce03f12b 609 lkid = (bucket << 16) | ls->ls_lkbtbl[bucket].counter++;
e7fd4179
DT		 610
611 list_for_each_entry(tmp, &ls->ls_lkbtbl[bucket].list,
612 lkb_idtbl_list) {
613 if (tmp->lkb_id != lkid)
614 continue;
615 lkid = 0;
616 break;
617 }
618 }
619
620 lkb->lkb_id = lkid;
621 list_add(&lkb->lkb_idtbl_list, &ls->ls_lkbtbl[bucket].list);
622 write_unlock(&ls->ls_lkbtbl[bucket].lock);
623
624 *lkb_ret = lkb;
625 return 0;
626}
627
628static struct dlm_lkb *__find_lkb(struct dlm_ls *ls, uint32_t lkid)
629{
e7fd4179 630 struct dlm_lkb *lkb;
ce03f12b 631 uint16_t bucket = (lkid >> 16);
e7fd4179
DT		 632
633 list_for_each_entry(lkb, &ls->ls_lkbtbl[bucket].list, lkb_idtbl_list) {
634 if (lkb->lkb_id == lkid)
635 return lkb;
636 }
637 return NULL;
638}
639
640static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
641{
642 struct dlm_lkb *lkb;
ce03f12b 643 uint16_t bucket = (lkid >> 16);
e7fd4179
DT		 644
645 if (bucket >= ls->ls_lkbtbl_size)
646 return -EBADSLT;
647
648 read_lock(&ls->ls_lkbtbl[bucket].lock);
649 lkb = __find_lkb(ls, lkid);
650 if (lkb)
651 kref_get(&lkb->lkb_ref);
652 read_unlock(&ls->ls_lkbtbl[bucket].lock);
653
654 *lkb_ret = lkb;
655 return lkb ? 0 : -ENOENT;
656}
657
658static void kill_lkb(struct kref *kref)
659{
660 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
661
662 /* All work is done after the return from kref_put() so we
663 can release the write_lock before the detach_lkb */
664
665 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
666}
667
b3f58d8f
DT		 668/* __put_lkb() is used when an lkb may not have an rsb attached to
669 it so we need to provide the lockspace explicitly */
670
671static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 672{
ce03f12b 673 uint16_t bucket = (lkb->lkb_id >> 16);
e7fd4179
DT		 674
675 write_lock(&ls->ls_lkbtbl[bucket].lock);
676 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
677 list_del(&lkb->lkb_idtbl_list);
678 write_unlock(&ls->ls_lkbtbl[bucket].lock);
679
680 detach_lkb(lkb);
681
682 /* for local/process lkbs, lvbptr points to caller's lksb */
683 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 684 dlm_free_lvb(lkb->lkb_lvbptr);
685 dlm_free_lkb(lkb);
e7fd4179
DT		 686 return 1;
687 } else {
688 write_unlock(&ls->ls_lkbtbl[bucket].lock);
689 return 0;
690 }
691}
692
693int dlm_put_lkb(struct dlm_lkb *lkb)
694{
b3f58d8f
DT		 695 struct dlm_ls *ls;
696
697 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
698 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
699
700 ls = lkb->lkb_resource->res_ls;
701 return __put_lkb(ls, lkb);
e7fd4179
DT		 702}
703
704/* This is only called to add a reference when the code already holds
705 a valid reference to the lkb, so there's no need for locking. */
706
707static inline void hold_lkb(struct dlm_lkb *lkb)
708{
709 kref_get(&lkb->lkb_ref);
710}
711
712/* This is called when we need to remove a reference and are certain
713 it's not the last ref. e.g. del_lkb is always called between a
714 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
715 put_lkb would work fine, but would involve unnecessary locking */
716
717static inline void unhold_lkb(struct dlm_lkb *lkb)
718{
719 int rv;
720 rv = kref_put(&lkb->lkb_ref, kill_lkb);
721 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
722}
723
724static void lkb_add_ordered(struct list_head *new, struct list_head *head,
725 int mode)
726{
727 struct dlm_lkb *lkb = NULL;
728
729 list_for_each_entry(lkb, head, lkb_statequeue)
730 if (lkb->lkb_rqmode < mode)
731 break;
732
733 if (!lkb)
734 list_add_tail(new, head);
735 else
736 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
737}
738
739/* add/remove lkb to rsb's grant/convert/wait queue */
740
741static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
742{
743 kref_get(&lkb->lkb_ref);
744
745 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
746
eeda418d
DT		 747 lkb->lkb_timestamp = ktime_get();
748
e7fd4179
DT		 749 lkb->lkb_status = status;
750
751 switch (status) {
752 case DLM_LKSTS_WAITING:
753 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
754 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
755 else
756 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
757 break;
758 case DLM_LKSTS_GRANTED:
759 /* convention says granted locks kept in order of grmode */
760 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
761 lkb->lkb_grmode);
762 break;
763 case DLM_LKSTS_CONVERT:
764 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
765 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
766 else
767 list_add_tail(&lkb->lkb_statequeue,
768 &r->res_convertqueue);
769 break;
770 default:
771 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
772 }
773}
774
775static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
776{
777 lkb->lkb_status = 0;
778 list_del(&lkb->lkb_statequeue);
779 unhold_lkb(lkb);
780}
781
782static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
783{
784 hold_lkb(lkb);
785 del_lkb(r, lkb);
786 add_lkb(r, lkb, sts);
787 unhold_lkb(lkb);
788}
789
ef0c2bb0
DT		 790static int msg_reply_type(int mstype)
791{
792 switch (mstype) {
793 case DLM_MSG_REQUEST:
794 return DLM_MSG_REQUEST_REPLY;
795 case DLM_MSG_CONVERT:
796 return DLM_MSG_CONVERT_REPLY;
797 case DLM_MSG_UNLOCK:
798 return DLM_MSG_UNLOCK_REPLY;
799 case DLM_MSG_CANCEL:
800 return DLM_MSG_CANCEL_REPLY;
801 case DLM_MSG_LOOKUP:
802 return DLM_MSG_LOOKUP_REPLY;
803 }
804 return -1;
805}
806
e7fd4179
DT		 807/* add/remove lkb from global waiters list of lkb's waiting for
808 a reply from a remote node */
809
ef0c2bb0 810static int add_to_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 811{
812 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 813 int error = 0;
e7fd4179 814
90135925 815 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 816
817 if (is_overlap_unlock(lkb) ||
818 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
819 error = -EINVAL;
820 goto out;
821 }
822
823 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
824 switch (mstype) {
825 case DLM_MSG_UNLOCK:
826 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
827 break;
828 case DLM_MSG_CANCEL:
829 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
830 break;
831 default:
832 error = -EBUSY;
833 goto out;
834 }
835 lkb->lkb_wait_count++;
836 hold_lkb(lkb);
837
43279e53 838 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
ef0c2bb0
DT		 839 lkb->lkb_id, lkb->lkb_wait_type, mstype,
840 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 841 goto out;
842 }
ef0c2bb0
DT		 843
844 DLM_ASSERT(!lkb->lkb_wait_count,
845 dlm_print_lkb(lkb);
846 printk("wait_count %d\n", lkb->lkb_wait_count););
847
848 lkb->lkb_wait_count++;
e7fd4179 849 lkb->lkb_wait_type = mstype;
ef0c2bb0 850 hold_lkb(lkb);
e7fd4179
DT		 851 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
852 out:
ef0c2bb0 853 if (error)
43279e53 854 log_error(ls, "addwait error %x %d flags %x %d %d %s",
ef0c2bb0
DT		 855 lkb->lkb_id, error, lkb->lkb_flags, mstype,
856 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 857 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 858 return error;
e7fd4179
DT		 859}
860
b790c3b7
DT		 861/* We clear the RESEND flag because we might be taking an lkb off the waiters
862 list as part of process_requestqueue (e.g. a lookup that has an optimized
863 request reply on the requestqueue) between dlm_recover_waiters_pre() which
864 set RESEND and dlm_recover_waiters_post() */
865
43279e53
DT		 866static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
867 struct dlm_message *ms)
e7fd4179 868{
ef0c2bb0
DT		 869 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
870 int overlap_done = 0;
e7fd4179 871
ef0c2bb0 872 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
43279e53 873 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 874 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
875 overlap_done = 1;
876 goto out_del;
e7fd4179 877 }
ef0c2bb0
DT		 878
879 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
43279e53 880 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 881 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
882 overlap_done = 1;
883 goto out_del;
884 }
885
43279e53
DT		 886 /* Cancel state was preemptively cleared by a successful convert,
887 see next comment, nothing to do. */
888
889 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
890 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
891 log_debug(ls, "remwait %x cancel_reply wait_type %d",
892 lkb->lkb_id, lkb->lkb_wait_type);
893 return -1;
894 }
895
896 /* Remove for the convert reply, and premptively remove for the
897 cancel reply. A convert has been granted while there's still
898 an outstanding cancel on it (the cancel is moot and the result
899 in the cancel reply should be 0). We preempt the cancel reply
900 because the app gets the convert result and then can follow up
901 with another op, like convert. This subsequent op would see the
902 lingering state of the cancel and fail with -EBUSY. */
903
904 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
905 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
906 is_overlap_cancel(lkb) && ms && !ms->m_result) {
907 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
908 lkb->lkb_id);
909 lkb->lkb_wait_type = 0;
910 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
911 lkb->lkb_wait_count--;
912 goto out_del;
913 }
914
ef0c2bb0
DT		 915 /* N.B. type of reply may not always correspond to type of original
916 msg due to lookup->request optimization, verify others? */
917
918 if (lkb->lkb_wait_type) {
919 lkb->lkb_wait_type = 0;
920 goto out_del;
921 }
922
43279e53
DT		 923 log_error(ls, "remwait error %x reply %d flags %x no wait_type",
924 lkb->lkb_id, mstype, lkb->lkb_flags);
ef0c2bb0
DT		 925 return -1;
926
927 out_del:
928 /* the force-unlock/cancel has completed and we haven't recvd a reply
929 to the op that was in progress prior to the unlock/cancel; we
930 give up on any reply to the earlier op. FIXME: not sure when/how
931 this would happen */
932
933 if (overlap_done && lkb->lkb_wait_type) {
43279e53 934 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
ef0c2bb0
DT		 935 lkb->lkb_id, mstype, lkb->lkb_wait_type);
936 lkb->lkb_wait_count--;
937 lkb->lkb_wait_type = 0;
938 }
939
940 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
941
b790c3b7 942 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 943 lkb->lkb_wait_count--;
944 if (!lkb->lkb_wait_count)
945 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 946 unhold_lkb(lkb);
ef0c2bb0 947 return 0;
e7fd4179
DT		 948}
949
ef0c2bb0 950static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 951{
952 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
953 int error;
954
90135925 955 mutex_lock(&ls->ls_waiters_mutex);
43279e53 956 error = _remove_from_waiters(lkb, mstype, NULL);
90135925 957 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 958 return error;
959}
960
ef0c2bb0
DT		 961/* Handles situations where we might be processing a "fake" or "stub" reply in
962 which we can't try to take waiters_mutex again. */
963
964static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
965{
966 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
967 int error;
968
969 if (ms != &ls->ls_stub_ms)
970 mutex_lock(&ls->ls_waiters_mutex);
43279e53 971 error = _remove_from_waiters(lkb, ms->m_type, ms);
ef0c2bb0
DT		 972 if (ms != &ls->ls_stub_ms)
973 mutex_unlock(&ls->ls_waiters_mutex);
974 return error;
975}
976
e7fd4179
DT		 977static void dir_remove(struct dlm_rsb *r)
978{
979 int to_nodeid;
980
981 if (dlm_no_directory(r->res_ls))
982 return;
983
984 to_nodeid = dlm_dir_nodeid(r);
985 if (to_nodeid != dlm_our_nodeid())
986 send_remove(r);
987 else
988 dlm_dir_remove_entry(r->res_ls, to_nodeid,
989 r->res_name, r->res_length);
990}
991
992/* FIXME: shouldn't this be able to exit as soon as one non-due rsb is
993 found since they are in order of newest to oldest? */
994
995static int shrink_bucket(struct dlm_ls *ls, int b)
996{
997 struct dlm_rsb *r;
998 int count = 0, found;
999
1000 for (;;) {
90135925 1001 found = 0;
c7be761a 1002 spin_lock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1003 list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss,
1004 res_hashchain) {
1005 if (!time_after_eq(jiffies, r->res_toss_time +
68c817a1 1006 dlm_config.ci_toss_secs * HZ))
e7fd4179 1007 continue;
90135925 1008 found = 1;
e7fd4179
DT		 1009 break;
1010 }
1011
1012 if (!found) {
c7be761a 1013 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1014 break;
1015 }
1016
1017 if (kref_put(&r->res_ref, kill_rsb)) {
1018 list_del(&r->res_hashchain);
c7be761a 1019 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1020
1021 if (is_master(r))
1022 dir_remove(r);
52bda2b5 1023 dlm_free_rsb(r);
e7fd4179
DT		 1024 count++;
1025 } else {
c7be761a 1026 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1027 log_error(ls, "tossed rsb in use %s", r->res_name);
1028 }
1029 }
1030
1031 return count;
1032}
1033
1034void dlm_scan_rsbs(struct dlm_ls *ls)
1035{
1036 int i;
1037
e7fd4179
DT		 1038 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1039 shrink_bucket(ls, i);
85e86edf
DT		 1040 if (dlm_locking_stopped(ls))
1041 break;
e7fd4179
DT		 1042 cond_resched();
1043 }
1044}
1045
3ae1acf9
DT		 1046static void add_timeout(struct dlm_lkb *lkb)
1047{
1048 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1049
eeda418d 1050 if (is_master_copy(lkb))
3ae1acf9 1051 return;
3ae1acf9
DT		 1052
1053 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1054 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1055 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1056 goto add_it;
1057 }
84d8cd69
DT		 1058 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1059 goto add_it;
3ae1acf9
DT		 1060 return;
1061
1062 add_it:
1063 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1064 mutex_lock(&ls->ls_timeout_mutex);
1065 hold_lkb(lkb);
3ae1acf9
DT		 1066 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1067 mutex_unlock(&ls->ls_timeout_mutex);
1068}
1069
1070static void del_timeout(struct dlm_lkb *lkb)
1071{
1072 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1073
1074 mutex_lock(&ls->ls_timeout_mutex);
1075 if (!list_empty(&lkb->lkb_time_list)) {
1076 list_del_init(&lkb->lkb_time_list);
1077 unhold_lkb(lkb);
1078 }
1079 mutex_unlock(&ls->ls_timeout_mutex);
1080}
1081
1082/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1083 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1084 and then lock rsb because of lock ordering in add_timeout. We may need
1085 to specify some special timeout-related bits in the lkb that are just to
1086 be accessed under the timeout_mutex. */
1087
1088void dlm_scan_timeout(struct dlm_ls *ls)
1089{
1090 struct dlm_rsb *r;
1091 struct dlm_lkb *lkb;
1092 int do_cancel, do_warn;
eeda418d 1093 s64 wait_us;
3ae1acf9
DT		 1094
1095 for (;;) {
1096 if (dlm_locking_stopped(ls))
1097 break;
1098
1099 do_cancel = 0;
1100 do_warn = 0;
1101 mutex_lock(&ls->ls_timeout_mutex);
1102 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1103
eeda418d
DT		 1104 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1105 lkb->lkb_timestamp));
1106
3ae1acf9 1107 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
eeda418d 1108 wait_us >= (lkb->lkb_timeout_cs * 10000))
3ae1acf9
DT		 1109 do_cancel = 1;
1110
1111 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
eeda418d 1112 wait_us >= dlm_config.ci_timewarn_cs * 10000)
3ae1acf9
DT		 1113 do_warn = 1;
1114
1115 if (!do_cancel && !do_warn)
1116 continue;
1117 hold_lkb(lkb);
1118 break;
1119 }
1120 mutex_unlock(&ls->ls_timeout_mutex);
1121
1122 if (!do_cancel && !do_warn)
1123 break;
1124
1125 r = lkb->lkb_resource;
1126 hold_rsb(r);
1127 lock_rsb(r);
1128
1129 if (do_warn) {
1130 /* clear flag so we only warn once */
1131 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1132 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1133 del_timeout(lkb);
1134 dlm_timeout_warn(lkb);
1135 }
1136
1137 if (do_cancel) {
b3cab7b9 1138 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1139 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1140 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1141 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1142 del_timeout(lkb);
1143 _cancel_lock(r, lkb);
1144 }
1145
1146 unlock_rsb(r);
1147 unhold_rsb(r);
1148 dlm_put_lkb(lkb);
1149 }
1150}
1151
1152/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1153 dlm_recoverd before checking/setting ls_recover_begin. */
1154
1155void dlm_adjust_timeouts(struct dlm_ls *ls)
1156{
1157 struct dlm_lkb *lkb;
eeda418d 1158 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
3ae1acf9
DT		 1159
1160 ls->ls_recover_begin = 0;
1161 mutex_lock(&ls->ls_timeout_mutex);
1162 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
eeda418d 1163 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
3ae1acf9
DT		 1164 mutex_unlock(&ls->ls_timeout_mutex);
1165}
1166
e7fd4179
DT		 1167/* lkb is master or local copy */
1168
1169static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1170{
1171 int b, len = r->res_ls->ls_lvblen;
1172
1173 /* b=1 lvb returned to caller
1174 b=0 lvb written to rsb or invalidated
1175 b=-1 do nothing */
1176
1177 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1178
1179 if (b == 1) {
1180 if (!lkb->lkb_lvbptr)
1181 return;
1182
1183 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1184 return;
1185
1186 if (!r->res_lvbptr)
1187 return;
1188
1189 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1190 lkb->lkb_lvbseq = r->res_lvbseq;
1191
1192 } else if (b == 0) {
1193 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1194 rsb_set_flag(r, RSB_VALNOTVALID);
1195 return;
1196 }
1197
1198 if (!lkb->lkb_lvbptr)
1199 return;
1200
1201 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1202 return;
1203
1204 if (!r->res_lvbptr)
52bda2b5 1205 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1206
1207 if (!r->res_lvbptr)
1208 return;
1209
1210 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1211 r->res_lvbseq++;
1212 lkb->lkb_lvbseq = r->res_lvbseq;
1213 rsb_clear_flag(r, RSB_VALNOTVALID);
1214 }
1215
1216 if (rsb_flag(r, RSB_VALNOTVALID))
1217 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1218}
1219
1220static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1221{
1222 if (lkb->lkb_grmode < DLM_LOCK_PW)
1223 return;
1224
1225 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1226 rsb_set_flag(r, RSB_VALNOTVALID);
1227 return;
1228 }
1229
1230 if (!lkb->lkb_lvbptr)
1231 return;
1232
1233 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1234 return;
1235
1236 if (!r->res_lvbptr)
52bda2b5 1237 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1238
1239 if (!r->res_lvbptr)
1240 return;
1241
1242 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
1243 r->res_lvbseq++;
1244 rsb_clear_flag(r, RSB_VALNOTVALID);
1245}
1246
1247/* lkb is process copy (pc) */
1248
1249static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1250 struct dlm_message *ms)
1251{
1252 int b;
1253
1254 if (!lkb->lkb_lvbptr)
1255 return;
1256
1257 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1258 return;
1259
597d0cae 1260 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 1261 if (b == 1) {
1262 int len = receive_extralen(ms);
a9cc9159
AV		 1263 if (len > DLM_RESNAME_MAXLEN)
1264 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 1265 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
1266 lkb->lkb_lvbseq = ms->m_lvbseq;
1267 }
1268}
1269
1270/* Manipulate lkb's on rsb's convert/granted/waiting queues
1271 remove_lock -- used for unlock, removes lkb from granted
1272 revert_lock -- used for cancel, moves lkb from convert to granted
1273 grant_lock -- used for request and convert, adds lkb to granted or
1274 moves lkb from convert or waiting to granted
1275
1276 Each of these is used for master or local copy lkb's. There is
1277 also a _pc() variation used to make the corresponding change on
1278 a process copy (pc) lkb. */
1279
1280static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1281{
1282 del_lkb(r, lkb);
1283 lkb->lkb_grmode = DLM_LOCK_IV;
1284 /* this unhold undoes the original ref from create_lkb()
1285 so this leads to the lkb being freed */
1286 unhold_lkb(lkb);
1287}
1288
1289static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1290{
1291 set_lvb_unlock(r, lkb);
1292 _remove_lock(r, lkb);
1293}
1294
1295static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1296{
1297 _remove_lock(r, lkb);
1298}
1299
ef0c2bb0
DT		 1300/* returns: 0 did nothing
1301 1 moved lock to granted
1302 -1 removed lock */
1303
1304static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1305{
ef0c2bb0
DT		 1306 int rv = 0;
1307
e7fd4179
DT		 1308 lkb->lkb_rqmode = DLM_LOCK_IV;
1309
1310 switch (lkb->lkb_status) {
597d0cae
DT		 1311 case DLM_LKSTS_GRANTED:
1312 break;
e7fd4179
DT		 1313 case DLM_LKSTS_CONVERT:
1314 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 1315 rv = 1;
e7fd4179
DT		 1316 break;
1317 case DLM_LKSTS_WAITING:
1318 del_lkb(r, lkb);
1319 lkb->lkb_grmode = DLM_LOCK_IV;
1320 /* this unhold undoes the original ref from create_lkb()
1321 so this leads to the lkb being freed */
1322 unhold_lkb(lkb);
ef0c2bb0 1323 rv = -1;
e7fd4179
DT		 1324 break;
1325 default:
1326 log_print("invalid status for revert %d", lkb->lkb_status);
1327 }
ef0c2bb0 1328 return rv;
e7fd4179
DT		 1329}
1330
ef0c2bb0 1331static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1332{
ef0c2bb0 1333 return revert_lock(r, lkb);
e7fd4179
DT		 1334}
1335
1336static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1337{
1338 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
1339 lkb->lkb_grmode = lkb->lkb_rqmode;
1340 if (lkb->lkb_status)
1341 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1342 else
1343 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
1344 }
1345
1346 lkb->lkb_rqmode = DLM_LOCK_IV;
e7fd4179
DT		 1347}
1348
1349static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1350{
1351 set_lvb_lock(r, lkb);
1352 _grant_lock(r, lkb);
1353 lkb->lkb_highbast = 0;
1354}
1355
1356static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1357 struct dlm_message *ms)
1358{
1359 set_lvb_lock_pc(r, lkb, ms);
1360 _grant_lock(r, lkb);
1361}
1362
1363/* called by grant_pending_locks() which means an async grant message must
1364 be sent to the requesting node in addition to granting the lock if the
1365 lkb belongs to a remote node. */
1366
1367static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
1368{
1369 grant_lock(r, lkb);
1370 if (is_master_copy(lkb))
1371 send_grant(r, lkb);
1372 else
1373 queue_cast(r, lkb, 0);
1374}
1375
7d3c1feb
DT		 1376/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
1377 change the granted/requested modes. We're munging things accordingly in
1378 the process copy.
1379 CONVDEADLK: our grmode may have been forced down to NL to resolve a
1380 conversion deadlock
1381 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
1382 compatible with other granted locks */
1383
1384static void munge_demoted(struct dlm_lkb *lkb, struct dlm_message *ms)
1385{
1386 if (ms->m_type != DLM_MSG_CONVERT_REPLY) {
1387 log_print("munge_demoted %x invalid reply type %d",
1388 lkb->lkb_id, ms->m_type);
1389 return;
1390 }
1391
1392 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
1393 log_print("munge_demoted %x invalid modes gr %d rq %d",
1394 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
1395 return;
1396 }
1397
1398 lkb->lkb_grmode = DLM_LOCK_NL;
1399}
1400
1401static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
1402{
1403 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
1404 ms->m_type != DLM_MSG_GRANT) {
1405 log_print("munge_altmode %x invalid reply type %d",
1406 lkb->lkb_id, ms->m_type);
1407 return;
1408 }
1409
1410 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
1411 lkb->lkb_rqmode = DLM_LOCK_PR;
1412 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
1413 lkb->lkb_rqmode = DLM_LOCK_CW;
1414 else {
1415 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
1416 dlm_print_lkb(lkb);
1417 }
1418}
1419
e7fd4179
DT		 1420static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
1421{
1422 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
1423 lkb_statequeue);
1424 if (lkb->lkb_id == first->lkb_id)
90135925 1425 return 1;
e7fd4179 1426
90135925 1427 return 0;
e7fd4179
DT		 1428}
1429
e7fd4179
DT		 1430/* Check if the given lkb conflicts with another lkb on the queue. */
1431
1432static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
1433{
1434 struct dlm_lkb *this;
1435
1436 list_for_each_entry(this, head, lkb_statequeue) {
1437 if (this == lkb)
1438 continue;
3bcd3687 1439 if (!modes_compat(this, lkb))
90135925 1440 return 1;
e7fd4179 1441 }
90135925 1442 return 0;
e7fd4179
DT		 1443}
1444
1445/*
1446 * "A conversion deadlock arises with a pair of lock requests in the converting
1447 * queue for one resource. The granted mode of each lock blocks the requested
1448 * mode of the other lock."
1449 *
c85d65e9
DT		 1450 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
1451 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 1452 *
1453 * Example:
1454 * Granted Queue: empty
1455 * Convert Queue: NL->EX (first lock)
1456 * PR->EX (second lock)
1457 *
1458 * The first lock can't be granted because of the granted mode of the second
1459 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 1460 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
1461 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
1462 * flag set and return DEMOTED in the lksb flags.
e7fd4179 1463 *
c85d65e9
DT		 1464 * Originally, this function detected conv-deadlk in a more limited scope:
1465 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
1466 * - if lkb1 was the first entry in the queue (not just earlier), and was
1467 * blocked by the granted mode of lkb2, and there was nothing on the
1468 * granted queue preventing lkb1 from being granted immediately, i.e.
1469 * lkb2 was the only thing preventing lkb1 from being granted.
1470 *
1471 * That second condition meant we'd only say there was conv-deadlk if
1472 * resolving it (by demotion) would lead to the first lock on the convert
1473 * queue being granted right away. It allowed conversion deadlocks to exist
1474 * between locks on the convert queue while they couldn't be granted anyway.
1475 *
1476 * Now, we detect and take action on conversion deadlocks immediately when
1477 * they're created, even if they may not be immediately consequential. If
1478 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
1479 * mode that would prevent lkb1's conversion from being granted, we do a
1480 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
1481 * I think this means that the lkb_is_ahead condition below should always
1482 * be zero, i.e. there will never be conv-deadlk between two locks that are
1483 * both already on the convert queue.
e7fd4179
DT		 1484 */
1485
c85d65e9 1486static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 1487{
c85d65e9
DT		 1488 struct dlm_lkb *lkb1;
1489 int lkb_is_ahead = 0;
e7fd4179 1490
c85d65e9
DT		 1491 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
1492 if (lkb1 == lkb2) {
1493 lkb_is_ahead = 1;
e7fd4179
DT		 1494 continue;
1495 }
1496
c85d65e9
DT		 1497 if (!lkb_is_ahead) {
1498 if (!modes_compat(lkb2, lkb1))
1499 return 1;
1500 } else {
1501 if (!modes_compat(lkb2, lkb1) &&
1502 !modes_compat(lkb1, lkb2))
1503 return 1;
1504 }
e7fd4179 1505 }
90135925 1506 return 0;
e7fd4179
DT		 1507}
1508
1509/*
1510 * Return 1 if the lock can be granted, 0 otherwise.
1511 * Also detect and resolve conversion deadlocks.
1512 *
1513 * lkb is the lock to be granted
1514 *
1515 * now is 1 if the function is being called in the context of the
1516 * immediate request, it is 0 if called later, after the lock has been
1517 * queued.
1518 *
1519 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
1520 */
1521
1522static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now)
1523{
1524 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
1525
1526 /*
1527 * 6-10: Version 5.4 introduced an option to address the phenomenon of
1528 * a new request for a NL mode lock being blocked.
1529 *
1530 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
1531 * request, then it would be granted. In essence, the use of this flag
1532 * tells the Lock Manager to expedite theis request by not considering
1533 * what may be in the CONVERTING or WAITING queues... As of this
1534 * writing, the EXPEDITE flag can be used only with new requests for NL
1535 * mode locks. This flag is not valid for conversion requests.
1536 *
1537 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
1538 * conversion or used with a non-NL requested mode. We also know an
1539 * EXPEDITE request is always granted immediately, so now must always
1540 * be 1. The full condition to grant an expedite request: (now &&
1541 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
1542 * therefore be shortened to just checking the flag.
1543 */
1544
1545 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 1546 return 1;
e7fd4179
DT		 1547
1548 /*
1549 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
1550 * added to the remaining conditions.
1551 */
1552
1553 if (queue_conflict(&r->res_grantqueue, lkb))
1554 goto out;
1555
1556 /*
1557 * 6-3: By default, a conversion request is immediately granted if the
1558 * requested mode is compatible with the modes of all other granted
1559 * locks
1560 */
1561
1562 if (queue_conflict(&r->res_convertqueue, lkb))
1563 goto out;
1564
1565 /*
1566 * 6-5: But the default algorithm for deciding whether to grant or
1567 * queue conversion requests does not by itself guarantee that such
1568 * requests are serviced on a "first come first serve" basis. This, in
1569 * turn, can lead to a phenomenon known as "indefinate postponement".
1570 *
1571 * 6-7: This issue is dealt with by using the optional QUECVT flag with
1572 * the system service employed to request a lock conversion. This flag
1573 * forces certain conversion requests to be queued, even if they are
1574 * compatible with the granted modes of other locks on the same
1575 * resource. Thus, the use of this flag results in conversion requests
1576 * being ordered on a "first come first servce" basis.
1577 *
1578 * DCT: This condition is all about new conversions being able to occur
1579 * "in place" while the lock remains on the granted queue (assuming
1580 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
1581 * doesn't _have_ to go onto the convert queue where it's processed in
1582 * order. The "now" variable is necessary to distinguish converts
1583 * being received and processed for the first time now, because once a
1584 * convert is moved to the conversion queue the condition below applies
1585 * requiring fifo granting.
1586 */
1587
1588 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 1589 return 1;
e7fd4179
DT		 1590
1591 /*
3bcd3687
DT		 1592 * The NOORDER flag is set to avoid the standard vms rules on grant
1593 * order.
e7fd4179
DT		 1594 */
1595
1596 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 1597 return 1;
e7fd4179
DT		 1598
1599 /*
1600 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
1601 * granted until all other conversion requests ahead of it are granted
1602 * and/or canceled.
1603 */
1604
1605 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 1606 return 1;
e7fd4179
DT		 1607
1608 /*
1609 * 6-4: By default, a new request is immediately granted only if all
1610 * three of the following conditions are satisfied when the request is
1611 * issued:
1612 * - The queue of ungranted conversion requests for the resource is
1613 * empty.
1614 * - The queue of ungranted new requests for the resource is empty.
1615 * - The mode of the new request is compatible with the most
1616 * restrictive mode of all granted locks on the resource.
1617 */
1618
1619 if (now && !conv && list_empty(&r->res_convertqueue) &&
1620 list_empty(&r->res_waitqueue))
90135925 1621 return 1;
e7fd4179
DT		 1622
1623 /*
1624 * 6-4: Once a lock request is in the queue of ungranted new requests,
1625 * it cannot be granted until the queue of ungranted conversion
1626 * requests is empty, all ungranted new requests ahead of it are
1627 * granted and/or canceled, and it is compatible with the granted mode
1628 * of the most restrictive lock granted on the resource.
1629 */
1630
1631 if (!now && !conv && list_empty(&r->res_convertqueue) &&
1632 first_in_list(lkb, &r->res_waitqueue))
90135925 1633 return 1;
e7fd4179 1634 out:
90135925 1635 return 0;
e7fd4179
DT		 1636}
1637
c85d65e9
DT		 1638static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
1639 int *err)
e7fd4179 1640{
e7fd4179
DT		 1641 int rv;
1642 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 1643 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
1644
1645 if (err)
1646 *err = 0;
e7fd4179
DT		 1647
1648 rv = _can_be_granted(r, lkb, now);
1649 if (rv)
1650 goto out;
1651
c85d65e9
DT		 1652 /*
1653 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
1654 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
1655 * cancels one of the locks.
1656 */
1657
1658 if (is_convert && can_be_queued(lkb) &&
1659 conversion_deadlock_detect(r, lkb)) {
1660 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
1661 lkb->lkb_grmode = DLM_LOCK_NL;
1662 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
1663 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1664 if (err)
1665 *err = -EDEADLK;
1666 else {
1667 log_print("can_be_granted deadlock %x now %d",
1668 lkb->lkb_id, now);
1669 dlm_dump_rsb(r);
1670 }
1671 }
e7fd4179 1672 goto out;
c85d65e9 1673 }
e7fd4179 1674
c85d65e9
DT		 1675 /*
1676 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
1677 * to grant a request in a mode other than the normal rqmode. It's a
1678 * simple way to provide a big optimization to applications that can
1679 * use them.
1680 */
1681
1682 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 1683 alt = DLM_LOCK_PR;
c85d65e9 1684 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 1685 alt = DLM_LOCK_CW;
1686
1687 if (alt) {
1688 lkb->lkb_rqmode = alt;
1689 rv = _can_be_granted(r, lkb, now);
1690 if (rv)
1691 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
1692 else
1693 lkb->lkb_rqmode = rqmode;
1694 }
1695 out:
1696 return rv;
1697}
1698
c85d65e9
DT		 1699/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
1700 for locks pending on the convert list. Once verified (watch for these
1701 log_prints), we should be able to just call _can_be_granted() and not
1702 bother with the demote/deadlk cases here (and there's no easy way to deal
1703 with a deadlk here, we'd have to generate something like grant_lock with
1704 the deadlk error.) */
1705
36509258
DT		 1706/* Returns the highest requested mode of all blocked conversions; sets
1707 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 1708
36509258 1709static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1710{
1711 struct dlm_lkb *lkb, *s;
1712 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 1713 int deadlk;
e7fd4179
DT		 1714
1715 quit = 0;
1716 restart:
1717 grant_restart = 0;
1718 demote_restart = 0;
1719 hi = DLM_LOCK_IV;
1720
1721 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
1722 demoted = is_demoted(lkb);
c85d65e9
DT		 1723 deadlk = 0;
1724
1725 if (can_be_granted(r, lkb, 0, &deadlk)) {
e7fd4179
DT		 1726 grant_lock_pending(r, lkb);
1727 grant_restart = 1;
c85d65e9 1728 continue;
e7fd4179 1729 }
c85d65e9
DT		 1730
1731 if (!demoted && is_demoted(lkb)) {
1732 log_print("WARN: pending demoted %x node %d %s",
1733 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1734 demote_restart = 1;
1735 continue;
1736 }
1737
1738 if (deadlk) {
1739 log_print("WARN: pending deadlock %x node %d %s",
1740 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1741 dlm_dump_rsb(r);
1742 continue;
1743 }
1744
1745 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 1746
1747 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
1748 *cw = 1;
e7fd4179
DT		 1749 }
1750
1751 if (grant_restart)
1752 goto restart;
1753 if (demote_restart && !quit) {
1754 quit = 1;
1755 goto restart;
1756 }
1757
1758 return max_t(int, high, hi);
1759}
1760
36509258 1761static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1762{
1763 struct dlm_lkb *lkb, *s;
1764
1765 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c85d65e9 1766 if (can_be_granted(r, lkb, 0, NULL))
e7fd4179 1767 grant_lock_pending(r, lkb);
36509258 1768 else {
e7fd4179 1769 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 1770 if (lkb->lkb_rqmode == DLM_LOCK_CW)
1771 *cw = 1;
1772 }
e7fd4179
DT		 1773 }
1774
1775 return high;
1776}
1777
36509258
DT		 1778/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
1779 on either the convert or waiting queue.
1780 high is the largest rqmode of all locks blocked on the convert or
1781 waiting queue. */
1782
1783static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
1784{
1785 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
1786 if (gr->lkb_highbast < DLM_LOCK_EX)
1787 return 1;
1788 return 0;
1789 }
1790
1791 if (gr->lkb_highbast < high &&
1792 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
1793 return 1;
1794 return 0;
1795}
1796
e7fd4179
DT		 1797static void grant_pending_locks(struct dlm_rsb *r)
1798{
1799 struct dlm_lkb *lkb, *s;
1800 int high = DLM_LOCK_IV;
36509258 1801 int cw = 0;
e7fd4179 1802
a345da3e 1803 DLM_ASSERT(is_master(r), dlm_dump_rsb(r););
e7fd4179 1804
36509258
DT		 1805 high = grant_pending_convert(r, high, &cw);
1806 high = grant_pending_wait(r, high, &cw);
e7fd4179
DT		 1807
1808 if (high == DLM_LOCK_IV)
1809 return;
1810
1811 /*
1812 * If there are locks left on the wait/convert queue then send blocking
1813 * ASTs to granted locks based on the largest requested mode (high)
36509258 1814 * found above.
e7fd4179
DT		 1815 */
1816
1817 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 1818 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
329fc4c3
DT		 1819 if (cw && high == DLM_LOCK_PR &&
1820 lkb->lkb_grmode == DLM_LOCK_PR)
36509258
DT		 1821 queue_bast(r, lkb, DLM_LOCK_CW);
1822 else
1823 queue_bast(r, lkb, high);
e7fd4179
DT		 1824 lkb->lkb_highbast = high;
1825 }
1826 }
1827}
1828
36509258
DT		 1829static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
1830{
1831 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
1832 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
1833 if (gr->lkb_highbast < DLM_LOCK_EX)
1834 return 1;
1835 return 0;
1836 }
1837
1838 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
1839 return 1;
1840 return 0;
1841}
1842
e7fd4179
DT		 1843static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
1844 struct dlm_lkb *lkb)
1845{
1846 struct dlm_lkb *gr;
1847
1848 list_for_each_entry(gr, head, lkb_statequeue) {
e5dae548 1849 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 1850 queue_bast(r, gr, lkb->lkb_rqmode);
1851 gr->lkb_highbast = lkb->lkb_rqmode;
1852 }
1853 }
1854}
1855
1856static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
1857{
1858 send_bast_queue(r, &r->res_grantqueue, lkb);
1859}
1860
1861static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
1862{
1863 send_bast_queue(r, &r->res_grantqueue, lkb);
1864 send_bast_queue(r, &r->res_convertqueue, lkb);
1865}
1866
1867/* set_master(r, lkb) -- set the master nodeid of a resource
1868
1869 The purpose of this function is to set the nodeid field in the given
1870 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
1871 known, it can just be copied to the lkb and the function will return
1872 0. If the rsb's nodeid is _not_ known, it needs to be looked up
1873 before it can be copied to the lkb.
1874
1875 When the rsb nodeid is being looked up remotely, the initial lkb
1876 causing the lookup is kept on the ls_waiters list waiting for the
1877 lookup reply. Other lkb's waiting for the same rsb lookup are kept
1878 on the rsb's res_lookup list until the master is verified.
1879
1880 Return values:
1881 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
1882 1: the rsb master is not available and the lkb has been placed on
1883 a wait queue
1884*/
1885
1886static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
1887{
1888 struct dlm_ls *ls = r->res_ls;
755b5eb8 1889 int i, error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 1890
1891 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
1892 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
1893 r->res_first_lkid = lkb->lkb_id;
1894 lkb->lkb_nodeid = r->res_nodeid;
1895 return 0;
1896 }
1897
1898 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
1899 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
1900 return 1;
1901 }
1902
1903 if (r->res_nodeid == 0) {
1904 lkb->lkb_nodeid = 0;
1905 return 0;
1906 }
1907
1908 if (r->res_nodeid > 0) {
1909 lkb->lkb_nodeid = r->res_nodeid;
1910 return 0;
1911 }
1912
a345da3e 1913 DLM_ASSERT(r->res_nodeid == -1, dlm_dump_rsb(r););
e7fd4179
DT		 1914
1915 dir_nodeid = dlm_dir_nodeid(r);
1916
1917 if (dir_nodeid != our_nodeid) {
1918 r->res_first_lkid = lkb->lkb_id;
1919 send_lookup(r, lkb);
1920 return 1;
1921 }
1922
755b5eb8 1923 for (i = 0; i < 2; i++) {
e7fd4179
DT		 1924 /* It's possible for dlm_scand to remove an old rsb for
1925 this same resource from the toss list, us to create
1926 a new one, look up the master locally, and find it
1927 already exists just before dlm_scand does the
1928 dir_remove() on the previous rsb. */
1929
1930 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
1931 r->res_length, &ret_nodeid);
1932 if (!error)
1933 break;
1934 log_debug(ls, "dir_lookup error %d %s", error, r->res_name);
1935 schedule();
1936 }
755b5eb8
DT		 1937 if (error && error != -EEXIST)
1938 return error;
e7fd4179
DT		 1939
1940 if (ret_nodeid == our_nodeid) {
1941 r->res_first_lkid = 0;
1942 r->res_nodeid = 0;
1943 lkb->lkb_nodeid = 0;
1944 } else {
1945 r->res_first_lkid = lkb->lkb_id;
1946 r->res_nodeid = ret_nodeid;
1947 lkb->lkb_nodeid = ret_nodeid;
1948 }
1949 return 0;
1950}
1951
1952static void process_lookup_list(struct dlm_rsb *r)
1953{
1954 struct dlm_lkb *lkb, *safe;
1955
1956 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 1957 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 1958 _request_lock(r, lkb);
1959 schedule();
1960 }
1961}
1962
1963/* confirm_master -- confirm (or deny) an rsb's master nodeid */
1964
1965static void confirm_master(struct dlm_rsb *r, int error)
1966{
1967 struct dlm_lkb *lkb;
1968
1969 if (!r->res_first_lkid)
1970 return;
1971
1972 switch (error) {
1973 case 0:
1974 case -EINPROGRESS:
1975 r->res_first_lkid = 0;
1976 process_lookup_list(r);
1977 break;
1978
1979 case -EAGAIN:
aec64e1b
DT		 1980 case -EBADR:
1981 case -ENOTBLK:
1982 /* the remote request failed and won't be retried (it was
1983 a NOQUEUE, or has been canceled/unlocked); make a waiting
1984 lkb the first_lkid */
e7fd4179
DT		 1985
1986 r->res_first_lkid = 0;
1987
1988 if (!list_empty(&r->res_lookup)) {
1989 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
1990 lkb_rsb_lookup);
ef0c2bb0 1991 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 1992 r->res_first_lkid = lkb->lkb_id;
1993 _request_lock(r, lkb);
761b9d3f 1994 }
e7fd4179
DT		 1995 break;
1996
1997 default:
1998 log_error(r->res_ls, "confirm_master unknown error %d", error);
1999 }
2000}
2001
2002static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 2003 int namelen, unsigned long timeout_cs,
2004 void (*ast) (void *astparam),
2005 void *astparam,
2006 void (*bast) (void *astparam, int mode),
2007 struct dlm_args *args)
e7fd4179
DT		 2008{
2009 int rv = -EINVAL;
2010
2011 /* check for invalid arg usage */
2012
2013 if (mode < 0 || mode > DLM_LOCK_EX)
2014 goto out;
2015
2016 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2017 goto out;
2018
2019 if (flags & DLM_LKF_CANCEL)
2020 goto out;
2021
2022 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2023 goto out;
2024
2025 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2026 goto out;
2027
2028 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2029 goto out;
2030
2031 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2032 goto out;
2033
2034 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2035 goto out;
2036
2037 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2038 goto out;
2039
2040 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2041 goto out;
2042
2043 if (!ast || !lksb)
2044 goto out;
2045
2046 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2047 goto out;
2048
e7fd4179
DT		 2049 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2050 goto out;
2051
2052 /* these args will be copied to the lkb in validate_lock_args,
2053 it cannot be done now because when converting locks, fields in
2054 an active lkb cannot be modified before locking the rsb */
2055
2056 args->flags = flags;
e5dae548
DT		 2057 args->astfn = ast;
2058 args->astparam = astparam;
2059 args->bastfn = bast;
d7db923e 2060 args->timeout = timeout_cs;
e7fd4179
DT		 2061 args->mode = mode;
2062 args->lksb = lksb;
e7fd4179
DT		 2063 rv = 0;
2064 out:
2065 return rv;
2066}
2067
2068static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2069{
2070 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2071 DLM_LKF_FORCEUNLOCK))
2072 return -EINVAL;
2073
ef0c2bb0
DT		 2074 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2075 return -EINVAL;
2076
e7fd4179 2077 args->flags = flags;
e5dae548 2078 args->astparam = astarg;
e7fd4179
DT		 2079 return 0;
2080}
2081
2082static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2083 struct dlm_args *args)
2084{
2085 int rv = -EINVAL;
2086
2087 if (args->flags & DLM_LKF_CONVERT) {
2088 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2089 goto out;
2090
2091 if (args->flags & DLM_LKF_QUECVT &&
2092 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2093 goto out;
2094
2095 rv = -EBUSY;
2096 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2097 goto out;
2098
2099 if (lkb->lkb_wait_type)
2100 goto out;
ef0c2bb0
DT		 2101
2102 if (is_overlap(lkb))
2103 goto out;
e7fd4179
DT		 2104 }
2105
2106 lkb->lkb_exflags = args->flags;
2107 lkb->lkb_sbflags = 0;
e5dae548 2108 lkb->lkb_astfn = args->astfn;
e7fd4179 2109 lkb->lkb_astparam = args->astparam;
e5dae548 2110 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2111 lkb->lkb_rqmode = args->mode;
2112 lkb->lkb_lksb = args->lksb;
2113 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2114 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2115 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2116 rv = 0;
2117 out:
43279e53
DT		 2118 if (rv)
2119 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2120 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2121 lkb->lkb_status, lkb->lkb_wait_type,
2122 lkb->lkb_resource->res_name);
e7fd4179
DT		 2123 return rv;
2124}
2125
ef0c2bb0
DT		 2126/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2127 for success */
2128
2129/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2130 because there may be a lookup in progress and it's valid to do
2131 cancel/unlockf on it */
2132
e7fd4179
DT		 2133static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2134{
ef0c2bb0 2135 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2136 int rv = -EINVAL;
2137
ef0c2bb0
DT		 2138 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2139 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2140 dlm_print_lkb(lkb);
e7fd4179 2141 goto out;
ef0c2bb0 2142 }
e7fd4179 2143
ef0c2bb0
DT		 2144 /* an lkb may still exist even though the lock is EOL'ed due to a
2145 cancel, unlock or failed noqueue request; an app can't use these
2146 locks; return same error as if the lkid had not been found at all */
e7fd4179 2147
ef0c2bb0
DT		 2148 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2149 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2150 rv = -ENOENT;
e7fd4179 2151 goto out;
ef0c2bb0 2152 }
e7fd4179 2153
ef0c2bb0
DT		 2154 /* an lkb may be waiting for an rsb lookup to complete where the
2155 lookup was initiated by another lock */
2156
42dc1601
DT		 2157 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2158 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2159 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2160 list_del_init(&lkb->lkb_rsb_lookup);
2161 queue_cast(lkb->lkb_resource, lkb,
2162 args->flags & DLM_LKF_CANCEL ?
2163 -DLM_ECANCEL : -DLM_EUNLOCK);
2164 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2165 }
42dc1601
DT		 2166 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2167 rv = -EBUSY;
2168 goto out;
ef0c2bb0
DT		 2169 }
2170
2171 /* cancel not allowed with another cancel/unlock in progress */
2172
2173 if (args->flags & DLM_LKF_CANCEL) {
2174 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2175 goto out;
2176
2177 if (is_overlap(lkb))
2178 goto out;
2179
3ae1acf9
DT		 2180 /* don't let scand try to do a cancel */
2181 del_timeout(lkb);
2182
ef0c2bb0
DT		 2183 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2184 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2185 rv = -EBUSY;
2186 goto out;
2187 }
2188
a536e381
DT		 2189 /* there's nothing to cancel */
2190 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2191 !lkb->lkb_wait_type) {
2192 rv = -EBUSY;
2193 goto out;
2194 }
2195
ef0c2bb0
DT		 2196 switch (lkb->lkb_wait_type) {
2197 case DLM_MSG_LOOKUP:
2198 case DLM_MSG_REQUEST:
2199 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2200 rv = -EBUSY;
2201 goto out;
2202 case DLM_MSG_UNLOCK:
2203 case DLM_MSG_CANCEL:
2204 goto out;
2205 }
2206 /* add_to_waiters() will set OVERLAP_CANCEL */
2207 goto out_ok;
2208 }
2209
2210 /* do we need to allow a force-unlock if there's a normal unlock
2211 already in progress? in what conditions could the normal unlock
2212 fail such that we'd want to send a force-unlock to be sure? */
2213
2214 if (args->flags & DLM_LKF_FORCEUNLOCK) {
2215 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
2216 goto out;
2217
2218 if (is_overlap_unlock(lkb))
2219 goto out;
e7fd4179 2220
3ae1acf9
DT		 2221 /* don't let scand try to do a cancel */
2222 del_timeout(lkb);
2223
ef0c2bb0
DT		 2224 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2225 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2226 rv = -EBUSY;
2227 goto out;
2228 }
2229
2230 switch (lkb->lkb_wait_type) {
2231 case DLM_MSG_LOOKUP:
2232 case DLM_MSG_REQUEST:
2233 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2234 rv = -EBUSY;
2235 goto out;
2236 case DLM_MSG_UNLOCK:
2237 goto out;
2238 }
2239 /* add_to_waiters() will set OVERLAP_UNLOCK */
2240 goto out_ok;
2241 }
2242
2243 /* normal unlock not allowed if there's any op in progress */
e7fd4179 2244 rv = -EBUSY;
ef0c2bb0 2245 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 2246 goto out;
2247
2248 out_ok:
ef0c2bb0
DT		 2249 /* an overlapping op shouldn't blow away exflags from other op */
2250 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 2251 lkb->lkb_sbflags = 0;
2252 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 2253 rv = 0;
2254 out:
ef0c2bb0
DT		 2255 if (rv)
2256 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
2257 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
2258 args->flags, lkb->lkb_wait_type,
2259 lkb->lkb_resource->res_name);
e7fd4179
DT		 2260 return rv;
2261}
2262
2263/*
2264 * Four stage 4 varieties:
2265 * do_request(), do_convert(), do_unlock(), do_cancel()
2266 * These are called on the master node for the given lock and
2267 * from the central locking logic.
2268 */
2269
2270static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2271{
2272 int error = 0;
2273
c85d65e9 2274 if (can_be_granted(r, lkb, 1, NULL)) {
e7fd4179
DT		 2275 grant_lock(r, lkb);
2276 queue_cast(r, lkb, 0);
2277 goto out;
2278 }
2279
2280 if (can_be_queued(lkb)) {
2281 error = -EINPROGRESS;
2282 add_lkb(r, lkb, DLM_LKSTS_WAITING);
2283 send_blocking_asts(r, lkb);
3ae1acf9 2284 add_timeout(lkb);
e7fd4179
DT		 2285 goto out;
2286 }
2287
2288 error = -EAGAIN;
2289 if (force_blocking_asts(lkb))
2290 send_blocking_asts_all(r, lkb);
2291 queue_cast(r, lkb, -EAGAIN);
2292
2293 out:
2294 return error;
2295}
2296
2297static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2298{
2299 int error = 0;
c85d65e9 2300 int deadlk = 0;
e7fd4179
DT		 2301
2302 /* changing an existing lock may allow others to be granted */
2303
c85d65e9 2304 if (can_be_granted(r, lkb, 1, &deadlk)) {
e7fd4179
DT		 2305 grant_lock(r, lkb);
2306 queue_cast(r, lkb, 0);
2307 grant_pending_locks(r);
2308 goto out;
2309 }
2310
c85d65e9
DT		 2311 /* can_be_granted() detected that this lock would block in a conversion
2312 deadlock, so we leave it on the granted queue and return EDEADLK in
2313 the ast for the convert. */
2314
2315 if (deadlk) {
2316 /* it's left on the granted queue */
2317 log_debug(r->res_ls, "deadlock %x node %d sts%d g%d r%d %s",
2318 lkb->lkb_id, lkb->lkb_nodeid, lkb->lkb_status,
2319 lkb->lkb_grmode, lkb->lkb_rqmode, r->res_name);
2320 revert_lock(r, lkb);
2321 queue_cast(r, lkb, -EDEADLK);
2322 error = -EDEADLK;
2323 goto out;
2324 }
2325
7d3c1feb
DT		 2326 /* is_demoted() means the can_be_granted() above set the grmode
2327 to NL, and left us on the granted queue. This auto-demotion
2328 (due to CONVDEADLK) might mean other locks, and/or this lock, are
2329 now grantable. We have to try to grant other converting locks
2330 before we try again to grant this one. */
2331
2332 if (is_demoted(lkb)) {
36509258 2333 grant_pending_convert(r, DLM_LOCK_IV, NULL);
7d3c1feb
DT		 2334 if (_can_be_granted(r, lkb, 1)) {
2335 grant_lock(r, lkb);
2336 queue_cast(r, lkb, 0);
e7fd4179 2337 grant_pending_locks(r);
7d3c1feb
DT		 2338 goto out;
2339 }
2340 /* else fall through and move to convert queue */
2341 }
2342
2343 if (can_be_queued(lkb)) {
e7fd4179
DT		 2344 error = -EINPROGRESS;
2345 del_lkb(r, lkb);
2346 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
2347 send_blocking_asts(r, lkb);
3ae1acf9 2348 add_timeout(lkb);
e7fd4179
DT		 2349 goto out;
2350 }
2351
2352 error = -EAGAIN;
2353 if (force_blocking_asts(lkb))
2354 send_blocking_asts_all(r, lkb);
2355 queue_cast(r, lkb, -EAGAIN);
2356
2357 out:
2358 return error;
2359}
2360
2361static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2362{
2363 remove_lock(r, lkb);
2364 queue_cast(r, lkb, -DLM_EUNLOCK);
2365 grant_pending_locks(r);
2366 return -DLM_EUNLOCK;
2367}
2368
ef0c2bb0 2369/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
907b9bce 2370
e7fd4179
DT		 2371static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2372{
ef0c2bb0
DT		 2373 int error;
2374
2375 error = revert_lock(r, lkb);
2376 if (error) {
2377 queue_cast(r, lkb, -DLM_ECANCEL);
2378 grant_pending_locks(r);
2379 return -DLM_ECANCEL;
2380 }
2381 return 0;
e7fd4179
DT		 2382}
2383
2384/*
2385 * Four stage 3 varieties:
2386 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
2387 */
2388
2389/* add a new lkb to a possibly new rsb, called by requesting process */
2390
2391static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2392{
2393 int error;
2394
2395 /* set_master: sets lkb nodeid from r */
2396
2397 error = set_master(r, lkb);
2398 if (error < 0)
2399 goto out;
2400 if (error) {
2401 error = 0;
2402 goto out;
2403 }
2404
2405 if (is_remote(r))
2406 /* receive_request() calls do_request() on remote node */
2407 error = send_request(r, lkb);
2408 else
2409 error = do_request(r, lkb);
2410 out:
2411 return error;
2412}
2413
3bcd3687 2414/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 2415
2416static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2417{
2418 int error;
2419
2420 if (is_remote(r))
2421 /* receive_convert() calls do_convert() on remote node */
2422 error = send_convert(r, lkb);
2423 else
2424 error = do_convert(r, lkb);
2425
2426 return error;
2427}
2428
2429/* remove an existing lkb from the granted queue */
2430
2431static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2432{
2433 int error;
2434
2435 if (is_remote(r))
2436 /* receive_unlock() calls do_unlock() on remote node */
2437 error = send_unlock(r, lkb);
2438 else
2439 error = do_unlock(r, lkb);
2440
2441 return error;
2442}
2443
2444/* remove an existing lkb from the convert or wait queue */
2445
2446static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2447{
2448 int error;
2449
2450 if (is_remote(r))
2451 /* receive_cancel() calls do_cancel() on remote node */
2452 error = send_cancel(r, lkb);
2453 else
2454 error = do_cancel(r, lkb);
2455
2456 return error;
2457}
2458
2459/*
2460 * Four stage 2 varieties:
2461 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
2462 */
2463
2464static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
2465 int len, struct dlm_args *args)
2466{
2467 struct dlm_rsb *r;
2468 int error;
2469
2470 error = validate_lock_args(ls, lkb, args);
2471 if (error)
2472 goto out;
2473
2474 error = find_rsb(ls, name, len, R_CREATE, &r);
2475 if (error)
2476 goto out;
2477
2478 lock_rsb(r);
2479
2480 attach_lkb(r, lkb);
2481 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
2482
2483 error = _request_lock(r, lkb);
2484
2485 unlock_rsb(r);
2486 put_rsb(r);
2487
2488 out:
2489 return error;
2490}
2491
2492static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2493 struct dlm_args *args)
2494{
2495 struct dlm_rsb *r;
2496 int error;
2497
2498 r = lkb->lkb_resource;
2499
2500 hold_rsb(r);
2501 lock_rsb(r);
2502
2503 error = validate_lock_args(ls, lkb, args);
2504 if (error)
2505 goto out;
2506
2507 error = _convert_lock(r, lkb);
2508 out:
2509 unlock_rsb(r);
2510 put_rsb(r);
2511 return error;
2512}
2513
2514static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2515 struct dlm_args *args)
2516{
2517 struct dlm_rsb *r;
2518 int error;
2519
2520 r = lkb->lkb_resource;
2521
2522 hold_rsb(r);
2523 lock_rsb(r);
2524
2525 error = validate_unlock_args(lkb, args);
2526 if (error)
2527 goto out;
2528
2529 error = _unlock_lock(r, lkb);
2530 out:
2531 unlock_rsb(r);
2532 put_rsb(r);
2533 return error;
2534}
2535
2536static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2537 struct dlm_args *args)
2538{
2539 struct dlm_rsb *r;
2540 int error;
2541
2542 r = lkb->lkb_resource;
2543
2544 hold_rsb(r);
2545 lock_rsb(r);
2546
2547 error = validate_unlock_args(lkb, args);
2548 if (error)
2549 goto out;
2550
2551 error = _cancel_lock(r, lkb);
2552 out:
2553 unlock_rsb(r);
2554 put_rsb(r);
2555 return error;
2556}
2557
2558/*
2559 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
2560 */
2561
2562int dlm_lock(dlm_lockspace_t *lockspace,
2563 int mode,
2564 struct dlm_lksb *lksb,
2565 uint32_t flags,
2566 void *name,
2567 unsigned int namelen,
2568 uint32_t parent_lkid,
2569 void (*ast) (void *astarg),
2570 void *astarg,
3bcd3687 2571 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 2572{
2573 struct dlm_ls *ls;
2574 struct dlm_lkb *lkb;
2575 struct dlm_args args;
2576 int error, convert = flags & DLM_LKF_CONVERT;
2577
2578 ls = dlm_find_lockspace_local(lockspace);
2579 if (!ls)
2580 return -EINVAL;
2581
85e86edf 2582 dlm_lock_recovery(ls);
e7fd4179
DT		 2583
2584 if (convert)
2585 error = find_lkb(ls, lksb->sb_lkid, &lkb);
2586 else
2587 error = create_lkb(ls, &lkb);
2588
2589 if (error)
2590 goto out;
2591
d7db923e 2592 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 2593 astarg, bast, &args);
e7fd4179
DT		 2594 if (error)
2595 goto out_put;
2596
2597 if (convert)
2598 error = convert_lock(ls, lkb, &args);
2599 else
2600 error = request_lock(ls, lkb, name, namelen, &args);
2601
2602 if (error == -EINPROGRESS)
2603 error = 0;
2604 out_put:
2605 if (convert || error)
b3f58d8f 2606 __put_lkb(ls, lkb);
c85d65e9 2607 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 2608 error = 0;
2609 out:
85e86edf 2610 dlm_unlock_recovery(ls);
e7fd4179
DT		 2611 dlm_put_lockspace(ls);
2612 return error;
2613}
2614
2615int dlm_unlock(dlm_lockspace_t *lockspace,
2616 uint32_t lkid,
2617 uint32_t flags,
2618 struct dlm_lksb *lksb,
2619 void *astarg)
2620{
2621 struct dlm_ls *ls;
2622 struct dlm_lkb *lkb;
2623 struct dlm_args args;
2624 int error;
2625
2626 ls = dlm_find_lockspace_local(lockspace);
2627 if (!ls)
2628 return -EINVAL;
2629
85e86edf 2630 dlm_lock_recovery(ls);
e7fd4179
DT		 2631
2632 error = find_lkb(ls, lkid, &lkb);
2633 if (error)
2634 goto out;
2635
2636 error = set_unlock_args(flags, astarg, &args);
2637 if (error)
2638 goto out_put;
2639
2640 if (flags & DLM_LKF_CANCEL)
2641 error = cancel_lock(ls, lkb, &args);
2642 else
2643 error = unlock_lock(ls, lkb, &args);
2644
2645 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
2646 error = 0;
ef0c2bb0
DT		 2647 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
2648 error = 0;
e7fd4179 2649 out_put:
b3f58d8f 2650 dlm_put_lkb(lkb);
e7fd4179 2651 out:
85e86edf 2652 dlm_unlock_recovery(ls);
e7fd4179
DT		 2653 dlm_put_lockspace(ls);
2654 return error;
2655}
2656
2657/*
2658 * send/receive routines for remote operations and replies
2659 *
2660 * send_args
2661 * send_common
2662 * send_request receive_request
2663 * send_convert receive_convert
2664 * send_unlock receive_unlock
2665 * send_cancel receive_cancel
2666 * send_grant receive_grant
2667 * send_bast receive_bast
2668 * send_lookup receive_lookup
2669 * send_remove receive_remove
2670 *
2671 * send_common_reply
2672 * receive_request_reply send_request_reply
2673 * receive_convert_reply send_convert_reply
2674 * receive_unlock_reply send_unlock_reply
2675 * receive_cancel_reply send_cancel_reply
2676 * receive_lookup_reply send_lookup_reply
2677 */
2678
7e4dac33
DT		 2679static int _create_message(struct dlm_ls *ls, int mb_len,
2680 int to_nodeid, int mstype,
2681 struct dlm_message **ms_ret,
2682 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 2683{
2684 struct dlm_message *ms;
2685 struct dlm_mhandle *mh;
2686 char *mb;
e7fd4179
DT		 2687
2688 /* get_buffer gives us a message handle (mh) that we need to
2689 pass into lowcomms_commit and a message buffer (mb) that we
2690 write our data into */
2691
44f487a5 2692 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, ls->ls_allocation, &mb);
e7fd4179
DT		 2693 if (!mh)
2694 return -ENOBUFS;
2695
2696 memset(mb, 0, mb_len);
2697
2698 ms = (struct dlm_message *) mb;
2699
2700 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 2701 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 2702 ms->m_header.h_nodeid = dlm_our_nodeid();
2703 ms->m_header.h_length = mb_len;
2704 ms->m_header.h_cmd = DLM_MSG;
2705
2706 ms->m_type = mstype;
2707
2708 *mh_ret = mh;
2709 *ms_ret = ms;
2710 return 0;
2711}
2712
7e4dac33
DT		 2713static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
2714 int to_nodeid, int mstype,
2715 struct dlm_message **ms_ret,
2716 struct dlm_mhandle **mh_ret)
2717{
2718 int mb_len = sizeof(struct dlm_message);
2719
2720 switch (mstype) {
2721 case DLM_MSG_REQUEST:
2722 case DLM_MSG_LOOKUP:
2723 case DLM_MSG_REMOVE:
2724 mb_len += r->res_length;
2725 break;
2726 case DLM_MSG_CONVERT:
2727 case DLM_MSG_UNLOCK:
2728 case DLM_MSG_REQUEST_REPLY:
2729 case DLM_MSG_CONVERT_REPLY:
2730 case DLM_MSG_GRANT:
2731 if (lkb && lkb->lkb_lvbptr)
2732 mb_len += r->res_ls->ls_lvblen;
2733 break;
2734 }
2735
2736 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
2737 ms_ret, mh_ret);
2738}
2739
e7fd4179
DT		 2740/* further lowcomms enhancements or alternate implementations may make
2741 the return value from this function useful at some point */
2742
2743static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
2744{
2745 dlm_message_out(ms);
2746 dlm_lowcomms_commit_buffer(mh);
2747 return 0;
2748}
2749
2750static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
2751 struct dlm_message *ms)
2752{
2753 ms->m_nodeid = lkb->lkb_nodeid;
2754 ms->m_pid = lkb->lkb_ownpid;
2755 ms->m_lkid = lkb->lkb_id;
2756 ms->m_remid = lkb->lkb_remid;
2757 ms->m_exflags = lkb->lkb_exflags;
2758 ms->m_sbflags = lkb->lkb_sbflags;
2759 ms->m_flags = lkb->lkb_flags;
2760 ms->m_lvbseq = lkb->lkb_lvbseq;
2761 ms->m_status = lkb->lkb_status;
2762 ms->m_grmode = lkb->lkb_grmode;
2763 ms->m_rqmode = lkb->lkb_rqmode;
2764 ms->m_hash = r->res_hash;
2765
2766 /* m_result and m_bastmode are set from function args,
2767 not from lkb fields */
2768
e5dae548 2769 if (lkb->lkb_bastfn)
e7fd4179 2770 ms->m_asts |= AST_BAST;
e5dae548 2771 if (lkb->lkb_astfn)
e7fd4179
DT		 2772 ms->m_asts |= AST_COMP;
2773
da49f36f
DT		 2774 /* compare with switch in create_message; send_remove() doesn't
2775 use send_args() */
e7fd4179 2776
da49f36f
DT		 2777 switch (ms->m_type) {
2778 case DLM_MSG_REQUEST:
2779 case DLM_MSG_LOOKUP:
2780 memcpy(ms->m_extra, r->res_name, r->res_length);
2781 break;
2782 case DLM_MSG_CONVERT:
2783 case DLM_MSG_UNLOCK:
2784 case DLM_MSG_REQUEST_REPLY:
2785 case DLM_MSG_CONVERT_REPLY:
2786 case DLM_MSG_GRANT:
2787 if (!lkb->lkb_lvbptr)
2788 break;
e7fd4179 2789 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 2790 break;
2791 }
e7fd4179
DT		 2792}
2793
2794static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
2795{
2796 struct dlm_message *ms;
2797 struct dlm_mhandle *mh;
2798 int to_nodeid, error;
2799
ef0c2bb0
DT		 2800 error = add_to_waiters(lkb, mstype);
2801 if (error)
2802 return error;
e7fd4179
DT		 2803
2804 to_nodeid = r->res_nodeid;
2805
2806 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
2807 if (error)
2808 goto fail;
2809
2810 send_args(r, lkb, ms);
2811
2812 error = send_message(mh, ms);
2813 if (error)
2814 goto fail;
2815 return 0;
2816
2817 fail:
ef0c2bb0 2818 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 2819 return error;
2820}
2821
2822static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2823{
2824 return send_common(r, lkb, DLM_MSG_REQUEST);
2825}
2826
2827static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2828{
2829 int error;
2830
2831 error = send_common(r, lkb, DLM_MSG_CONVERT);
2832
2833 /* down conversions go without a reply from the master */
2834 if (!error && down_conversion(lkb)) {
ef0c2bb0
DT		 2835 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2836 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179 2837 r->res_ls->ls_stub_ms.m_result = 0;
32f105a1 2838 r->res_ls->ls_stub_ms.m_flags = lkb->lkb_flags;
e7fd4179
DT		 2839 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
2840 }
2841
2842 return error;
2843}
2844
2845/* FIXME: if this lkb is the only lock we hold on the rsb, then set
2846 MASTER_UNCERTAIN to force the next request on the rsb to confirm
2847 that the master is still correct. */
2848
2849static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2850{
2851 return send_common(r, lkb, DLM_MSG_UNLOCK);
2852}
2853
2854static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2855{
2856 return send_common(r, lkb, DLM_MSG_CANCEL);
2857}
2858
2859static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
2860{
2861 struct dlm_message *ms;
2862 struct dlm_mhandle *mh;
2863 int to_nodeid, error;
2864
2865 to_nodeid = lkb->lkb_nodeid;
2866
2867 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
2868 if (error)
2869 goto out;
2870
2871 send_args(r, lkb, ms);
2872
2873 ms->m_result = 0;
2874
2875 error = send_message(mh, ms);
2876 out:
2877 return error;
2878}
2879
2880static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
2881{
2882 struct dlm_message *ms;
2883 struct dlm_mhandle *mh;
2884 int to_nodeid, error;
2885
2886 to_nodeid = lkb->lkb_nodeid;
2887
2888 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
2889 if (error)
2890 goto out;
2891
2892 send_args(r, lkb, ms);
2893
2894 ms->m_bastmode = mode;
2895
2896 error = send_message(mh, ms);
2897 out:
2898 return error;
2899}
2900
2901static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
2902{
2903 struct dlm_message *ms;
2904 struct dlm_mhandle *mh;
2905 int to_nodeid, error;
2906
ef0c2bb0
DT		 2907 error = add_to_waiters(lkb, DLM_MSG_LOOKUP);
2908 if (error)
2909 return error;
e7fd4179
DT		 2910
2911 to_nodeid = dlm_dir_nodeid(r);
2912
2913 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
2914 if (error)
2915 goto fail;
2916
2917 send_args(r, lkb, ms);
2918
2919 error = send_message(mh, ms);
2920 if (error)
2921 goto fail;
2922 return 0;
2923
2924 fail:
ef0c2bb0 2925 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 2926 return error;
2927}
2928
2929static int send_remove(struct dlm_rsb *r)
2930{
2931 struct dlm_message *ms;
2932 struct dlm_mhandle *mh;
2933 int to_nodeid, error;
2934
2935 to_nodeid = dlm_dir_nodeid(r);
2936
2937 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
2938 if (error)
2939 goto out;
2940
2941 memcpy(ms->m_extra, r->res_name, r->res_length);
2942 ms->m_hash = r->res_hash;
2943
2944 error = send_message(mh, ms);
2945 out:
2946 return error;
2947}
2948
2949static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
2950 int mstype, int rv)
2951{
2952 struct dlm_message *ms;
2953 struct dlm_mhandle *mh;
2954 int to_nodeid, error;
2955
2956 to_nodeid = lkb->lkb_nodeid;
2957
2958 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
2959 if (error)
2960 goto out;
2961
2962 send_args(r, lkb, ms);
2963
2964 ms->m_result = rv;
2965
2966 error = send_message(mh, ms);
2967 out:
2968 return error;
2969}
2970
2971static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2972{
2973 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
2974}
2975
2976static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2977{
2978 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
2979}
2980
2981static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2982{
2983 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
2984}
2985
2986static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
2987{
2988 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
2989}
2990
2991static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
2992 int ret_nodeid, int rv)
2993{
2994 struct dlm_rsb *r = &ls->ls_stub_rsb;
2995 struct dlm_message *ms;
2996 struct dlm_mhandle *mh;
2997 int error, nodeid = ms_in->m_header.h_nodeid;
2998
2999 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3000 if (error)
3001 goto out;
3002
3003 ms->m_lkid = ms_in->m_lkid;
3004 ms->m_result = rv;
3005 ms->m_nodeid = ret_nodeid;
3006
3007 error = send_message(mh, ms);
3008 out:
3009 return error;
3010}
3011
3012/* which args we save from a received message depends heavily on the type
3013 of message, unlike the send side where we can safely send everything about
3014 the lkb for any type of message */
3015
3016static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3017{
3018 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 3019 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 3020 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3021 (ms->m_flags & 0x0000FFFF);
3022}
3023
3024static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3025{
3026 lkb->lkb_sbflags = ms->m_sbflags;
3027 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3028 (ms->m_flags & 0x0000FFFF);
3029}
3030
3031static int receive_extralen(struct dlm_message *ms)
3032{
3033 return (ms->m_header.h_length - sizeof(struct dlm_message));
3034}
3035
e7fd4179
DT		 3036static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3037 struct dlm_message *ms)
3038{
3039 int len;
3040
3041 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3042 if (!lkb->lkb_lvbptr)
52bda2b5 3043 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 3044 if (!lkb->lkb_lvbptr)
3045 return -ENOMEM;
3046 len = receive_extralen(ms);
a9cc9159
AV		 3047 if (len > DLM_RESNAME_MAXLEN)
3048 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 3049 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3050 }
3051 return 0;
3052}
3053
e5dae548
DT		 3054static void fake_bastfn(void *astparam, int mode)
3055{
3056 log_print("fake_bastfn should not be called");
3057}
3058
3059static void fake_astfn(void *astparam)
3060{
3061 log_print("fake_astfn should not be called");
3062}
3063
e7fd4179
DT		 3064static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3065 struct dlm_message *ms)
3066{
3067 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3068 lkb->lkb_ownpid = ms->m_pid;
3069 lkb->lkb_remid = ms->m_lkid;
3070 lkb->lkb_grmode = DLM_LOCK_IV;
3071 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548
DT		 3072
3073 lkb->lkb_bastfn = (ms->m_asts & AST_BAST) ? &fake_bastfn : NULL;
3074 lkb->lkb_astfn = (ms->m_asts & AST_COMP) ? &fake_astfn : NULL;
e7fd4179 3075
8d07fd50
DT		 3076 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3077 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3078 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3079 if (!lkb->lkb_lvbptr)
3080 return -ENOMEM;
3081 }
e7fd4179
DT		 3082
3083 return 0;
3084}
3085
3086static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3087 struct dlm_message *ms)
3088{
e7fd4179
DT		 3089 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3090 return -EBUSY;
3091
e7fd4179
DT		 3092 if (receive_lvb(ls, lkb, ms))
3093 return -ENOMEM;
3094
3095 lkb->lkb_rqmode = ms->m_rqmode;
3096 lkb->lkb_lvbseq = ms->m_lvbseq;
3097
3098 return 0;
3099}
3100
3101static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3102 struct dlm_message *ms)
3103{
e7fd4179
DT		 3104 if (receive_lvb(ls, lkb, ms))
3105 return -ENOMEM;
3106 return 0;
3107}
3108
3109/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3110 uses to send a reply and that the remote end uses to process the reply. */
3111
3112static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3113{
3114 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3115 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3116 lkb->lkb_remid = ms->m_lkid;
3117}
3118
c54e04b0
DT		 3119/* This is called after the rsb is locked so that we can safely inspect
3120 fields in the lkb. */
3121
3122static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3123{
3124 int from = ms->m_header.h_nodeid;
3125 int error = 0;
3126
3127 switch (ms->m_type) {
3128 case DLM_MSG_CONVERT:
3129 case DLM_MSG_UNLOCK:
3130 case DLM_MSG_CANCEL:
3131 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3132 error = -EINVAL;
3133 break;
3134
3135 case DLM_MSG_CONVERT_REPLY:
3136 case DLM_MSG_UNLOCK_REPLY:
3137 case DLM_MSG_CANCEL_REPLY:
3138 case DLM_MSG_GRANT:
3139 case DLM_MSG_BAST:
3140 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3141 error = -EINVAL;
3142 break;
3143
3144 case DLM_MSG_REQUEST_REPLY:
3145 if (!is_process_copy(lkb))
3146 error = -EINVAL;
3147 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3148 error = -EINVAL;
3149 break;
3150
3151 default:
3152 error = -EINVAL;
3153 }
3154
3155 if (error)
3156 log_error(lkb->lkb_resource->res_ls,
3157 "ignore invalid message %d from %d %x %x %x %d",
3158 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
3159 lkb->lkb_flags, lkb->lkb_nodeid);
3160 return error;
3161}
3162
e7fd4179
DT		 3163static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
3164{
3165 struct dlm_lkb *lkb;
3166 struct dlm_rsb *r;
3167 int error, namelen;
3168
3169 error = create_lkb(ls, &lkb);
3170 if (error)
3171 goto fail;
3172
3173 receive_flags(lkb, ms);
3174 lkb->lkb_flags |= DLM_IFL_MSTCPY;
3175 error = receive_request_args(ls, lkb, ms);
3176 if (error) {
b3f58d8f 3177 __put_lkb(ls, lkb);
e7fd4179
DT		 3178 goto fail;
3179 }
3180
3181 namelen = receive_extralen(ms);
3182
3183 error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r);
3184 if (error) {
b3f58d8f 3185 __put_lkb(ls, lkb);
e7fd4179
DT		 3186 goto fail;
3187 }
3188
3189 lock_rsb(r);
3190
3191 attach_lkb(r, lkb);
3192 error = do_request(r, lkb);
3193 send_request_reply(r, lkb, error);
3194
3195 unlock_rsb(r);
3196 put_rsb(r);
3197
3198 if (error == -EINPROGRESS)
3199 error = 0;
3200 if (error)
b3f58d8f 3201 dlm_put_lkb(lkb);
e7fd4179
DT		 3202 return;
3203
3204 fail:
3205 setup_stub_lkb(ls, ms);
3206 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3207}
3208
3209static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
3210{
3211 struct dlm_lkb *lkb;
3212 struct dlm_rsb *r;
90135925 3213 int error, reply = 1;
e7fd4179
DT		 3214
3215 error = find_lkb(ls, ms->m_remid, &lkb);
3216 if (error)
3217 goto fail;
3218
3219 r = lkb->lkb_resource;
3220
3221 hold_rsb(r);
3222 lock_rsb(r);
3223
c54e04b0
DT		 3224 error = validate_message(lkb, ms);
3225 if (error)
3226 goto out;
3227
e7fd4179
DT		 3228 receive_flags(lkb, ms);
3229 error = receive_convert_args(ls, lkb, ms);
3230 if (error)
c54e04b0 3231 goto out_reply;
e7fd4179
DT		 3232 reply = !down_conversion(lkb);
3233
3234 error = do_convert(r, lkb);
c54e04b0 3235 out_reply:
e7fd4179
DT		 3236 if (reply)
3237 send_convert_reply(r, lkb, error);
c54e04b0 3238 out:
e7fd4179
DT		 3239 unlock_rsb(r);
3240 put_rsb(r);
b3f58d8f 3241 dlm_put_lkb(lkb);
e7fd4179
DT		 3242 return;
3243
3244 fail:
3245 setup_stub_lkb(ls, ms);
3246 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3247}
3248
3249static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
3250{
3251 struct dlm_lkb *lkb;
3252 struct dlm_rsb *r;
3253 int error;
3254
3255 error = find_lkb(ls, ms->m_remid, &lkb);
3256 if (error)
3257 goto fail;
3258
3259 r = lkb->lkb_resource;
3260
3261 hold_rsb(r);
3262 lock_rsb(r);
3263
c54e04b0
DT		 3264 error = validate_message(lkb, ms);
3265 if (error)
3266 goto out;
3267
e7fd4179
DT		 3268 receive_flags(lkb, ms);
3269 error = receive_unlock_args(ls, lkb, ms);
3270 if (error)
c54e04b0 3271 goto out_reply;
e7fd4179
DT		 3272
3273 error = do_unlock(r, lkb);
c54e04b0 3274 out_reply:
e7fd4179 3275 send_unlock_reply(r, lkb, error);
c54e04b0 3276 out:
e7fd4179
DT		 3277 unlock_rsb(r);
3278 put_rsb(r);
b3f58d8f 3279 dlm_put_lkb(lkb);
e7fd4179
DT		 3280 return;
3281
3282 fail:
3283 setup_stub_lkb(ls, ms);
3284 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3285}
3286
3287static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
3288{
3289 struct dlm_lkb *lkb;
3290 struct dlm_rsb *r;
3291 int error;
3292
3293 error = find_lkb(ls, ms->m_remid, &lkb);
3294 if (error)
3295 goto fail;
3296
3297 receive_flags(lkb, ms);
3298
3299 r = lkb->lkb_resource;
3300
3301 hold_rsb(r);
3302 lock_rsb(r);
3303
c54e04b0
DT		 3304 error = validate_message(lkb, ms);
3305 if (error)
3306 goto out;
3307
e7fd4179
DT		 3308 error = do_cancel(r, lkb);
3309 send_cancel_reply(r, lkb, error);
c54e04b0 3310 out:
e7fd4179
DT		 3311 unlock_rsb(r);
3312 put_rsb(r);
b3f58d8f 3313 dlm_put_lkb(lkb);
e7fd4179
DT		 3314 return;
3315
3316 fail:
3317 setup_stub_lkb(ls, ms);
3318 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3319}
3320
3321static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
3322{
3323 struct dlm_lkb *lkb;
3324 struct dlm_rsb *r;
3325 int error;
3326
3327 error = find_lkb(ls, ms->m_remid, &lkb);
3328 if (error) {
c54e04b0
DT		 3329 log_debug(ls, "receive_grant from %d no lkb %x",
3330 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3331 return;
3332 }
e7fd4179
DT		 3333
3334 r = lkb->lkb_resource;
3335
3336 hold_rsb(r);
3337 lock_rsb(r);
3338
c54e04b0
DT		 3339 error = validate_message(lkb, ms);
3340 if (error)
3341 goto out;
3342
e7fd4179 3343 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 3344 if (is_altmode(lkb))
3345 munge_altmode(lkb, ms);
e7fd4179
DT		 3346 grant_lock_pc(r, lkb, ms);
3347 queue_cast(r, lkb, 0);
c54e04b0 3348 out:
e7fd4179
DT		 3349 unlock_rsb(r);
3350 put_rsb(r);
b3f58d8f 3351 dlm_put_lkb(lkb);
e7fd4179
DT		 3352}
3353
3354static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
3355{
3356 struct dlm_lkb *lkb;
3357 struct dlm_rsb *r;
3358 int error;
3359
3360 error = find_lkb(ls, ms->m_remid, &lkb);
3361 if (error) {
c54e04b0
DT		 3362 log_debug(ls, "receive_bast from %d no lkb %x",
3363 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3364 return;
3365 }
e7fd4179
DT		 3366
3367 r = lkb->lkb_resource;
3368
3369 hold_rsb(r);
3370 lock_rsb(r);
3371
c54e04b0
DT		 3372 error = validate_message(lkb, ms);
3373 if (error)
3374 goto out;
e7fd4179 3375
c54e04b0
DT		 3376 queue_bast(r, lkb, ms->m_bastmode);
3377 out:
e7fd4179
DT		 3378 unlock_rsb(r);
3379 put_rsb(r);
b3f58d8f 3380 dlm_put_lkb(lkb);
e7fd4179
DT		 3381}
3382
3383static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
3384{
3385 int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid;
3386
3387 from_nodeid = ms->m_header.h_nodeid;
3388 our_nodeid = dlm_our_nodeid();
3389
3390 len = receive_extralen(ms);
3391
3392 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3393 if (dir_nodeid != our_nodeid) {
3394 log_error(ls, "lookup dir_nodeid %d from %d",
3395 dir_nodeid, from_nodeid);
3396 error = -EINVAL;
3397 ret_nodeid = -1;
3398 goto out;
3399 }
3400
3401 error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid);
3402
3403 /* Optimization: we're master so treat lookup as a request */
3404 if (!error && ret_nodeid == our_nodeid) {
3405 receive_request(ls, ms);
3406 return;
3407 }
3408 out:
3409 send_lookup_reply(ls, ms, ret_nodeid, error);
3410}
3411
3412static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
3413{
3414 int len, dir_nodeid, from_nodeid;
3415
3416 from_nodeid = ms->m_header.h_nodeid;
3417
3418 len = receive_extralen(ms);
3419
3420 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3421 if (dir_nodeid != dlm_our_nodeid()) {
3422 log_error(ls, "remove dir entry dir_nodeid %d from %d",
3423 dir_nodeid, from_nodeid);
3424 return;
3425 }
3426
3427 dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len);
3428}
3429
8499137d
DT		 3430static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
3431{
3432 do_purge(ls, ms->m_nodeid, ms->m_pid);
3433}
3434
e7fd4179
DT		 3435static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
3436{
3437 struct dlm_lkb *lkb;
3438 struct dlm_rsb *r;
ef0c2bb0 3439 int error, mstype, result;
e7fd4179
DT		 3440
3441 error = find_lkb(ls, ms->m_remid, &lkb);
3442 if (error) {
c54e04b0
DT		 3443 log_debug(ls, "receive_request_reply from %d no lkb %x",
3444 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3445 return;
3446 }
e7fd4179 3447
e7fd4179
DT		 3448 r = lkb->lkb_resource;
3449 hold_rsb(r);
3450 lock_rsb(r);
3451
c54e04b0
DT		 3452 error = validate_message(lkb, ms);
3453 if (error)
3454 goto out;
3455
ef0c2bb0
DT		 3456 mstype = lkb->lkb_wait_type;
3457 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
3458 if (error)
3459 goto out;
3460
e7fd4179
DT		 3461 /* Optimization: the dir node was also the master, so it took our
3462 lookup as a request and sent request reply instead of lookup reply */
3463 if (mstype == DLM_MSG_LOOKUP) {
3464 r->res_nodeid = ms->m_header.h_nodeid;
3465 lkb->lkb_nodeid = r->res_nodeid;
3466 }
3467
ef0c2bb0
DT		 3468 /* this is the value returned from do_request() on the master */
3469 result = ms->m_result;
3470
3471 switch (result) {
e7fd4179 3472 case -EAGAIN:
ef0c2bb0 3473 /* request would block (be queued) on remote master */
e7fd4179
DT		 3474 queue_cast(r, lkb, -EAGAIN);
3475 confirm_master(r, -EAGAIN);
ef0c2bb0 3476 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 3477 break;
3478
3479 case -EINPROGRESS:
3480 case 0:
3481 /* request was queued or granted on remote master */
3482 receive_flags_reply(lkb, ms);
3483 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 3484 if (is_altmode(lkb))
3485 munge_altmode(lkb, ms);
3ae1acf9 3486 if (result) {
e7fd4179 3487 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 3488 add_timeout(lkb);
3489 } else {
e7fd4179
DT		 3490 grant_lock_pc(r, lkb, ms);
3491 queue_cast(r, lkb, 0);
3492 }
ef0c2bb0 3493 confirm_master(r, result);
e7fd4179
DT		 3494 break;
3495
597d0cae 3496 case -EBADR:
e7fd4179
DT		 3497 case -ENOTBLK:
3498 /* find_rsb failed to find rsb or rsb wasn't master */
ef0c2bb0
DT		 3499 log_debug(ls, "receive_request_reply %x %x master diff %d %d",
3500 lkb->lkb_id, lkb->lkb_flags, r->res_nodeid, result);
e7fd4179
DT		 3501 r->res_nodeid = -1;
3502 lkb->lkb_nodeid = -1;
ef0c2bb0
DT		 3503
3504 if (is_overlap(lkb)) {
3505 /* we'll ignore error in cancel/unlock reply */
3506 queue_cast_overlap(r, lkb);
aec64e1b 3507 confirm_master(r, result);
ef0c2bb0
DT		 3508 unhold_lkb(lkb); /* undoes create_lkb() */
3509 } else
3510 _request_lock(r, lkb);
e7fd4179
DT		 3511 break;
3512
3513 default:
ef0c2bb0
DT		 3514 log_error(ls, "receive_request_reply %x error %d",
3515 lkb->lkb_id, result);
e7fd4179
DT		 3516 }
3517
ef0c2bb0
DT		 3518 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
3519 log_debug(ls, "receive_request_reply %x result %d unlock",
3520 lkb->lkb_id, result);
3521 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3522 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3523 send_unlock(r, lkb);
3524 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
3525 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
3526 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3527 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3528 send_cancel(r, lkb);
3529 } else {
3530 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3531 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3532 }
3533 out:
e7fd4179
DT		 3534 unlock_rsb(r);
3535 put_rsb(r);
b3f58d8f 3536 dlm_put_lkb(lkb);
e7fd4179
DT		 3537}
3538
3539static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3540 struct dlm_message *ms)
3541{
e7fd4179 3542 /* this is the value returned from do_convert() on the master */
ef0c2bb0 3543 switch (ms->m_result) {
e7fd4179
DT		 3544 case -EAGAIN:
3545 /* convert would block (be queued) on remote master */
3546 queue_cast(r, lkb, -EAGAIN);
3547 break;
3548
c85d65e9
DT		 3549 case -EDEADLK:
3550 receive_flags_reply(lkb, ms);
3551 revert_lock_pc(r, lkb);
3552 queue_cast(r, lkb, -EDEADLK);
3553 break;
3554
e7fd4179
DT		 3555 case -EINPROGRESS:
3556 /* convert was queued on remote master */
7d3c1feb
DT		 3557 receive_flags_reply(lkb, ms);
3558 if (is_demoted(lkb))
3559 munge_demoted(lkb, ms);
e7fd4179
DT		 3560 del_lkb(r, lkb);
3561 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3562 add_timeout(lkb);
e7fd4179
DT		 3563 break;
3564
3565 case 0:
3566 /* convert was granted on remote master */
3567 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 3568 if (is_demoted(lkb))
3569 munge_demoted(lkb, ms);
e7fd4179
DT		 3570 grant_lock_pc(r, lkb, ms);
3571 queue_cast(r, lkb, 0);
3572 break;
3573
3574 default:
ef0c2bb0
DT		 3575 log_error(r->res_ls, "receive_convert_reply %x error %d",
3576 lkb->lkb_id, ms->m_result);
e7fd4179
DT		 3577 }
3578}
3579
3580static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3581{
3582 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3583 int error;
e7fd4179
DT		 3584
3585 hold_rsb(r);
3586 lock_rsb(r);
3587
c54e04b0
DT		 3588 error = validate_message(lkb, ms);
3589 if (error)
3590 goto out;
3591
ef0c2bb0
DT		 3592 /* stub reply can happen with waiters_mutex held */
3593 error = remove_from_waiters_ms(lkb, ms);
3594 if (error)
3595 goto out;
e7fd4179 3596
ef0c2bb0
DT		 3597 __receive_convert_reply(r, lkb, ms);
3598 out:
e7fd4179
DT		 3599 unlock_rsb(r);
3600 put_rsb(r);
3601}
3602
3603static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
3604{
3605 struct dlm_lkb *lkb;
3606 int error;
3607
3608 error = find_lkb(ls, ms->m_remid, &lkb);
3609 if (error) {
c54e04b0
DT		 3610 log_debug(ls, "receive_convert_reply from %d no lkb %x",
3611 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3612 return;
3613 }
e7fd4179 3614
e7fd4179 3615 _receive_convert_reply(lkb, ms);
b3f58d8f 3616 dlm_put_lkb(lkb);
e7fd4179
DT		 3617}
3618
3619static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3620{
3621 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3622 int error;
e7fd4179
DT		 3623
3624 hold_rsb(r);
3625 lock_rsb(r);
3626
c54e04b0
DT		 3627 error = validate_message(lkb, ms);
3628 if (error)
3629 goto out;
3630
ef0c2bb0
DT		 3631 /* stub reply can happen with waiters_mutex held */
3632 error = remove_from_waiters_ms(lkb, ms);
3633 if (error)
3634 goto out;
3635
e7fd4179
DT		 3636 /* this is the value returned from do_unlock() on the master */
3637
ef0c2bb0 3638 switch (ms->m_result) {
e7fd4179
DT		 3639 case -DLM_EUNLOCK:
3640 receive_flags_reply(lkb, ms);
3641 remove_lock_pc(r, lkb);
3642 queue_cast(r, lkb, -DLM_EUNLOCK);
3643 break;
ef0c2bb0
DT		 3644 case -ENOENT:
3645 break;
e7fd4179 3646 default:
ef0c2bb0
DT		 3647 log_error(r->res_ls, "receive_unlock_reply %x error %d",
3648 lkb->lkb_id, ms->m_result);
e7fd4179 3649 }
ef0c2bb0 3650 out:
e7fd4179
DT		 3651 unlock_rsb(r);
3652 put_rsb(r);
3653}
3654
3655static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
3656{
3657 struct dlm_lkb *lkb;
3658 int error;
3659
3660 error = find_lkb(ls, ms->m_remid, &lkb);
3661 if (error) {
c54e04b0
DT		 3662 log_debug(ls, "receive_unlock_reply from %d no lkb %x",
3663 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3664 return;
3665 }
e7fd4179 3666
e7fd4179 3667 _receive_unlock_reply(lkb, ms);
b3f58d8f 3668 dlm_put_lkb(lkb);
e7fd4179
DT		 3669}
3670
3671static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3672{
3673 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3674 int error;
e7fd4179
DT		 3675
3676 hold_rsb(r);
3677 lock_rsb(r);
3678
c54e04b0
DT		 3679 error = validate_message(lkb, ms);
3680 if (error)
3681 goto out;
3682
ef0c2bb0
DT		 3683 /* stub reply can happen with waiters_mutex held */
3684 error = remove_from_waiters_ms(lkb, ms);
3685 if (error)
3686 goto out;
3687
e7fd4179
DT		 3688 /* this is the value returned from do_cancel() on the master */
3689
ef0c2bb0 3690 switch (ms->m_result) {
e7fd4179
DT		 3691 case -DLM_ECANCEL:
3692 receive_flags_reply(lkb, ms);
3693 revert_lock_pc(r, lkb);
84d8cd69 3694 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3695 break;
3696 case 0:
e7fd4179
DT		 3697 break;
3698 default:
ef0c2bb0
DT		 3699 log_error(r->res_ls, "receive_cancel_reply %x error %d",
3700 lkb->lkb_id, ms->m_result);
e7fd4179 3701 }
ef0c2bb0 3702 out:
e7fd4179
DT		 3703 unlock_rsb(r);
3704 put_rsb(r);
3705}
3706
3707static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
3708{
3709 struct dlm_lkb *lkb;
3710 int error;
3711
3712 error = find_lkb(ls, ms->m_remid, &lkb);
3713 if (error) {
c54e04b0
DT		 3714 log_debug(ls, "receive_cancel_reply from %d no lkb %x",
3715 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3716 return;
3717 }
e7fd4179 3718
e7fd4179 3719 _receive_cancel_reply(lkb, ms);
b3f58d8f 3720 dlm_put_lkb(lkb);
e7fd4179
DT		 3721}
3722
3723static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
3724{
3725 struct dlm_lkb *lkb;
3726 struct dlm_rsb *r;
3727 int error, ret_nodeid;
3728
3729 error = find_lkb(ls, ms->m_lkid, &lkb);
3730 if (error) {
3731 log_error(ls, "receive_lookup_reply no lkb");
3732 return;
3733 }
3734
ef0c2bb0 3735 /* ms->m_result is the value returned by dlm_dir_lookup on dir node
e7fd4179 3736 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 3737
3738 r = lkb->lkb_resource;
3739 hold_rsb(r);
3740 lock_rsb(r);
3741
ef0c2bb0
DT		 3742 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3743 if (error)
3744 goto out;
3745
e7fd4179
DT		 3746 ret_nodeid = ms->m_nodeid;
3747 if (ret_nodeid == dlm_our_nodeid()) {
3748 r->res_nodeid = 0;
3749 ret_nodeid = 0;
3750 r->res_first_lkid = 0;
3751 } else {
3752 /* set_master() will copy res_nodeid to lkb_nodeid */
3753 r->res_nodeid = ret_nodeid;
3754 }
3755
ef0c2bb0
DT		 3756 if (is_overlap(lkb)) {
3757 log_debug(ls, "receive_lookup_reply %x unlock %x",
3758 lkb->lkb_id, lkb->lkb_flags);
3759 queue_cast_overlap(r, lkb);
3760 unhold_lkb(lkb); /* undoes create_lkb() */
3761 goto out_list;
3762 }
3763
e7fd4179
DT		 3764 _request_lock(r, lkb);
3765
ef0c2bb0 3766 out_list:
e7fd4179
DT		 3767 if (!ret_nodeid)
3768 process_lookup_list(r);
ef0c2bb0 3769 out:
e7fd4179
DT		 3770 unlock_rsb(r);
3771 put_rsb(r);
b3f58d8f 3772 dlm_put_lkb(lkb);
e7fd4179
DT		 3773}
3774
c36258b5 3775static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179 3776{
46b43eed
DT		 3777 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
3778 log_debug(ls, "ignore non-member message %d from %d %x %x %d",
3779 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
3780 ms->m_remid, ms->m_result);
3781 return;
3782 }
3783
e7fd4179
DT		 3784 switch (ms->m_type) {
3785
3786 /* messages sent to a master node */
3787
3788 case DLM_MSG_REQUEST:
3789 receive_request(ls, ms);
3790 break;
3791
3792 case DLM_MSG_CONVERT:
3793 receive_convert(ls, ms);
3794 break;
3795
3796 case DLM_MSG_UNLOCK:
3797 receive_unlock(ls, ms);
3798 break;
3799
3800 case DLM_MSG_CANCEL:
3801 receive_cancel(ls, ms);
3802 break;
3803
3804 /* messages sent from a master node (replies to above) */
3805
3806 case DLM_MSG_REQUEST_REPLY:
3807 receive_request_reply(ls, ms);
3808 break;
3809
3810 case DLM_MSG_CONVERT_REPLY:
3811 receive_convert_reply(ls, ms);
3812 break;
3813
3814 case DLM_MSG_UNLOCK_REPLY:
3815 receive_unlock_reply(ls, ms);
3816 break;
3817
3818 case DLM_MSG_CANCEL_REPLY:
3819 receive_cancel_reply(ls, ms);
3820 break;
3821
3822 /* messages sent from a master node (only two types of async msg) */
3823
3824 case DLM_MSG_GRANT:
3825 receive_grant(ls, ms);
3826 break;
3827
3828 case DLM_MSG_BAST:
3829 receive_bast(ls, ms);
3830 break;
3831
3832 /* messages sent to a dir node */
3833
3834 case DLM_MSG_LOOKUP:
3835 receive_lookup(ls, ms);
3836 break;
3837
3838 case DLM_MSG_REMOVE:
3839 receive_remove(ls, ms);
3840 break;
3841
3842 /* messages sent from a dir node (remove has no reply) */
3843
3844 case DLM_MSG_LOOKUP_REPLY:
3845 receive_lookup_reply(ls, ms);
3846 break;
3847
8499137d
DT		 3848 /* other messages */
3849
3850 case DLM_MSG_PURGE:
3851 receive_purge(ls, ms);
3852 break;
3853
e7fd4179
DT		 3854 default:
3855 log_error(ls, "unknown message type %d", ms->m_type);
3856 }
3857
e7fd4179 3858 dlm_astd_wake();
e7fd4179
DT		 3859}
3860
c36258b5
DT		 3861/* If the lockspace is in recovery mode (locking stopped), then normal
3862 messages are saved on the requestqueue for processing after recovery is
3863 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
3864 messages off the requestqueue before we process new ones. This occurs right
3865 after recovery completes when we transition from saving all messages on
3866 requestqueue, to processing all the saved messages, to processing new
3867 messages as they arrive. */
e7fd4179 3868
c36258b5
DT		 3869static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
3870 int nodeid)
3871{
3872 if (dlm_locking_stopped(ls)) {
8b0d8e03 3873 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 3874 } else {
3875 dlm_wait_requestqueue(ls);
3876 _receive_message(ls, ms);
3877 }
3878}
3879
3880/* This is called by dlm_recoverd to process messages that were saved on
3881 the requestqueue. */
3882
3883void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms)
3884{
3885 _receive_message(ls, ms);
3886}
3887
3888/* This is called by the midcomms layer when something is received for
3889 the lockspace. It could be either a MSG (normal message sent as part of
3890 standard locking activity) or an RCOM (recovery message sent as part of
3891 lockspace recovery). */
3892
eef7d739 3893void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 3894{
eef7d739 3895 struct dlm_header *hd = &p->header;
c36258b5
DT		 3896 struct dlm_ls *ls;
3897 int type = 0;
3898
3899 switch (hd->h_cmd) {
3900 case DLM_MSG:
eef7d739
AV		 3901 dlm_message_in(&p->message);
3902 type = p->message.m_type;
c36258b5
DT		 3903 break;
3904 case DLM_RCOM:
eef7d739
AV		 3905 dlm_rcom_in(&p->rcom);
3906 type = p->rcom.rc_type;
c36258b5
DT		 3907 break;
3908 default:
3909 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
3910 return;
3911 }
3912
3913 if (hd->h_nodeid != nodeid) {
3914 log_print("invalid h_nodeid %d from %d lockspace %x",
3915 hd->h_nodeid, nodeid, hd->h_lockspace);
3916 return;
3917 }
3918
3919 ls = dlm_find_lockspace_global(hd->h_lockspace);
3920 if (!ls) {
594199eb
DT		 3921 if (dlm_config.ci_log_debug)
3922 log_print("invalid lockspace %x from %d cmd %d type %d",
3923 hd->h_lockspace, nodeid, hd->h_cmd, type);
c36258b5
DT		 3924
3925 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 3926 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 3927 return;
3928 }
3929
3930 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
3931 be inactive (in this ls) before transitioning to recovery mode */
3932
3933 down_read(&ls->ls_recv_active);
3934 if (hd->h_cmd == DLM_MSG)
eef7d739 3935 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 3936 else
eef7d739 3937 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 3938 up_read(&ls->ls_recv_active);
3939
3940 dlm_put_lockspace(ls);
3941}
e7fd4179
DT		 3942
3943static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb)
3944{
3945 if (middle_conversion(lkb)) {
3946 hold_lkb(lkb);
ef0c2bb0 3947 ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179 3948 ls->ls_stub_ms.m_result = -EINPROGRESS;
075529b5 3949 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 3950 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179
DT		 3951 _receive_convert_reply(lkb, &ls->ls_stub_ms);
3952
3953 /* Same special case as in receive_rcom_lock_args() */
3954 lkb->lkb_grmode = DLM_LOCK_IV;
3955 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
3956 unhold_lkb(lkb);
3957
3958 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
3959 lkb->lkb_flags |= DLM_IFL_RESEND;
3960 }
3961
3962 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
3963 conversions are async; there's no reply from the remote master */
3964}
3965
3966/* A waiting lkb needs recovery if the master node has failed, or
3967 the master node is changing (only when no directory is used) */
3968
3969static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb)
3970{
3971 if (dlm_is_removed(ls, lkb->lkb_nodeid))
3972 return 1;
3973
3974 if (!dlm_no_directory(ls))
3975 return 0;
3976
3977 if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid)
3978 return 1;
3979
3980 return 0;
3981}
3982
3983/* Recovery for locks that are waiting for replies from nodes that are now
3984 gone. We can just complete unlocks and cancels by faking a reply from the
3985 dead node. Requests and up-conversions we flag to be resent after
3986 recovery. Down-conversions can just be completed with a fake reply like
3987 unlocks. Conversions between PR and CW need special attention. */
3988
3989void dlm_recover_waiters_pre(struct dlm_ls *ls)
3990{
3991 struct dlm_lkb *lkb, *safe;
601342ce 3992 int wait_type, stub_unlock_result, stub_cancel_result;
e7fd4179 3993
90135925 3994 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 3995
3996 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
3997 log_debug(ls, "pre recover waiter lkid %x type %d flags %x",
3998 lkb->lkb_id, lkb->lkb_wait_type, lkb->lkb_flags);
3999
4000 /* all outstanding lookups, regardless of destination will be
4001 resent after recovery is done */
4002
4003 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
4004 lkb->lkb_flags |= DLM_IFL_RESEND;
4005 continue;
4006 }
4007
4008 if (!waiter_needs_recovery(ls, lkb))
4009 continue;
4010
601342ce
DT		 4011 wait_type = lkb->lkb_wait_type;
4012 stub_unlock_result = -DLM_EUNLOCK;
4013 stub_cancel_result = -DLM_ECANCEL;
4014
4015 /* Main reply may have been received leaving a zero wait_type,
4016 but a reply for the overlapping op may not have been
4017 received. In that case we need to fake the appropriate
4018 reply for the overlap op. */
4019
4020 if (!wait_type) {
4021 if (is_overlap_cancel(lkb)) {
4022 wait_type = DLM_MSG_CANCEL;
4023 if (lkb->lkb_grmode == DLM_LOCK_IV)
4024 stub_cancel_result = 0;
4025 }
4026 if (is_overlap_unlock(lkb)) {
4027 wait_type = DLM_MSG_UNLOCK;
4028 if (lkb->lkb_grmode == DLM_LOCK_IV)
4029 stub_unlock_result = -ENOENT;
4030 }
4031
4032 log_debug(ls, "rwpre overlap %x %x %d %d %d",
4033 lkb->lkb_id, lkb->lkb_flags, wait_type,
4034 stub_cancel_result, stub_unlock_result);
4035 }
4036
4037 switch (wait_type) {
e7fd4179
DT		 4038
4039 case DLM_MSG_REQUEST:
4040 lkb->lkb_flags |= DLM_IFL_RESEND;
4041 break;
4042
4043 case DLM_MSG_CONVERT:
4044 recover_convert_waiter(ls, lkb);
4045 break;
4046
4047 case DLM_MSG_UNLOCK:
4048 hold_lkb(lkb);
ef0c2bb0 4049 ls->ls_stub_ms.m_type = DLM_MSG_UNLOCK_REPLY;
601342ce 4050 ls->ls_stub_ms.m_result = stub_unlock_result;
075529b5 4051 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 4052 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179 4053 _receive_unlock_reply(lkb, &ls->ls_stub_ms);
b3f58d8f 4054 dlm_put_lkb(lkb);
e7fd4179
DT		 4055 break;
4056
4057 case DLM_MSG_CANCEL:
4058 hold_lkb(lkb);
ef0c2bb0 4059 ls->ls_stub_ms.m_type = DLM_MSG_CANCEL_REPLY;
601342ce 4060 ls->ls_stub_ms.m_result = stub_cancel_result;
075529b5 4061 ls->ls_stub_ms.m_flags = lkb->lkb_flags;
c54e04b0 4062 ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
e7fd4179 4063 _receive_cancel_reply(lkb, &ls->ls_stub_ms);
b3f58d8f 4064 dlm_put_lkb(lkb);
e7fd4179
DT		 4065 break;
4066
4067 default:
601342ce
DT		 4068 log_error(ls, "invalid lkb wait_type %d %d",
4069 lkb->lkb_wait_type, wait_type);
e7fd4179 4070 }
81456807 4071 schedule();
e7fd4179 4072 }
90135925 4073 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4074}
4075
ef0c2bb0 4076static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 4077{
4078 struct dlm_lkb *lkb;
ef0c2bb0 4079 int found = 0;
e7fd4179 4080
90135925 4081 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4082 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
4083 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 4084 hold_lkb(lkb);
4085 found = 1;
e7fd4179
DT		 4086 break;
4087 }
4088 }
90135925 4089 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 4090
ef0c2bb0 4091 if (!found)
e7fd4179 4092 lkb = NULL;
ef0c2bb0 4093 return lkb;
e7fd4179
DT		 4094}
4095
4096/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
4097 master or dir-node for r. Processing the lkb may result in it being placed
4098 back on waiters. */
4099
ef0c2bb0
DT		 4100/* We do this after normal locking has been enabled and any saved messages
4101 (in requestqueue) have been processed. We should be confident that at
4102 this point we won't get or process a reply to any of these waiting
4103 operations. But, new ops may be coming in on the rsbs/locks here from
4104 userspace or remotely. */
4105
4106/* there may have been an overlap unlock/cancel prior to recovery or after
4107 recovery. if before, the lkb may still have a pos wait_count; if after, the
4108 overlap flag would just have been set and nothing new sent. we can be
4109 confident here than any replies to either the initial op or overlap ops
4110 prior to recovery have been received. */
4111
e7fd4179
DT		 4112int dlm_recover_waiters_post(struct dlm_ls *ls)
4113{
4114 struct dlm_lkb *lkb;
4115 struct dlm_rsb *r;
ef0c2bb0 4116 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 4117
4118 while (1) {
4119 if (dlm_locking_stopped(ls)) {
4120 log_debug(ls, "recover_waiters_post aborted");
4121 error = -EINTR;
4122 break;
4123 }
4124
ef0c2bb0
DT		 4125 lkb = find_resend_waiter(ls);
4126 if (!lkb)
e7fd4179
DT		 4127 break;
4128
4129 r = lkb->lkb_resource;
ef0c2bb0
DT		 4130 hold_rsb(r);
4131 lock_rsb(r);
4132
4133 mstype = lkb->lkb_wait_type;
4134 oc = is_overlap_cancel(lkb);
4135 ou = is_overlap_unlock(lkb);
4136 err = 0;
e7fd4179
DT		 4137
4138 log_debug(ls, "recover_waiters_post %x type %d flags %x %s",
4139 lkb->lkb_id, mstype, lkb->lkb_flags, r->res_name);
4140
ef0c2bb0
DT		 4141 /* At this point we assume that we won't get a reply to any
4142 previous op or overlap op on this lock. First, do a big
4143 remove_from_waiters() for all previous ops. */
4144
4145 lkb->lkb_flags &= ~DLM_IFL_RESEND;
4146 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4147 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4148 lkb->lkb_wait_type = 0;
4149 lkb->lkb_wait_count = 0;
4150 mutex_lock(&ls->ls_waiters_mutex);
4151 list_del_init(&lkb->lkb_wait_reply);
4152 mutex_unlock(&ls->ls_waiters_mutex);
4153 unhold_lkb(lkb); /* for waiters list */
4154
4155 if (oc || ou) {
4156 /* do an unlock or cancel instead of resending */
4157 switch (mstype) {
4158 case DLM_MSG_LOOKUP:
4159 case DLM_MSG_REQUEST:
4160 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
4161 -DLM_ECANCEL);
4162 unhold_lkb(lkb); /* undoes create_lkb() */
4163 break;
4164 case DLM_MSG_CONVERT:
4165 if (oc) {
4166 queue_cast(r, lkb, -DLM_ECANCEL);
4167 } else {
4168 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
4169 _unlock_lock(r, lkb);
4170 }
4171 break;
4172 default:
4173 err = 1;
4174 }
4175 } else {
4176 switch (mstype) {
4177 case DLM_MSG_LOOKUP:
4178 case DLM_MSG_REQUEST:
4179 _request_lock(r, lkb);
4180 if (is_master(r))
4181 confirm_master(r, 0);
4182 break;
4183 case DLM_MSG_CONVERT:
4184 _convert_lock(r, lkb);
4185 break;
4186 default:
4187 err = 1;
4188 }
e7fd4179 4189 }
ef0c2bb0
DT		 4190
4191 if (err)
4192 log_error(ls, "recover_waiters_post %x %d %x %d %d",
4193 lkb->lkb_id, mstype, lkb->lkb_flags, oc, ou);
4194 unlock_rsb(r);
4195 put_rsb(r);
4196 dlm_put_lkb(lkb);
e7fd4179
DT		 4197 }
4198
4199 return error;
4200}
4201
4202static void purge_queue(struct dlm_rsb *r, struct list_head *queue,
4203 int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb))
4204{
4205 struct dlm_ls *ls = r->res_ls;
4206 struct dlm_lkb *lkb, *safe;
4207
4208 list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) {
4209 if (test(ls, lkb)) {
97a35d1e 4210 rsb_set_flag(r, RSB_LOCKS_PURGED);
e7fd4179
DT		 4211 del_lkb(r, lkb);
4212 /* this put should free the lkb */
b3f58d8f 4213 if (!dlm_put_lkb(lkb))
e7fd4179
DT		 4214 log_error(ls, "purged lkb not released");
4215 }
4216 }
4217}
4218
4219static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4220{
4221 return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid));
4222}
4223
4224static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4225{
4226 return is_master_copy(lkb);
4227}
4228
4229static void purge_dead_locks(struct dlm_rsb *r)
4230{
4231 purge_queue(r, &r->res_grantqueue, &purge_dead_test);
4232 purge_queue(r, &r->res_convertqueue, &purge_dead_test);
4233 purge_queue(r, &r->res_waitqueue, &purge_dead_test);
4234}
4235
4236void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
4237{
4238 purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test);
4239 purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test);
4240 purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test);
4241}
4242
4243/* Get rid of locks held by nodes that are gone. */
4244
4245int dlm_purge_locks(struct dlm_ls *ls)
4246{
4247 struct dlm_rsb *r;
4248
4249 log_debug(ls, "dlm_purge_locks");
4250
4251 down_write(&ls->ls_root_sem);
4252 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
4253 hold_rsb(r);
4254 lock_rsb(r);
4255 if (is_master(r))
4256 purge_dead_locks(r);
4257 unlock_rsb(r);
4258 unhold_rsb(r);
4259
4260 schedule();
4261 }
4262 up_write(&ls->ls_root_sem);
4263
4264 return 0;
4265}
4266
97a35d1e
DT		 4267static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
4268{
4269 struct dlm_rsb *r, *r_ret = NULL;
4270
c7be761a 4271 spin_lock(&ls->ls_rsbtbl[bucket].lock);
97a35d1e
DT		 4272 list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list, res_hashchain) {
4273 if (!rsb_flag(r, RSB_LOCKS_PURGED))
4274 continue;
4275 hold_rsb(r);
4276 rsb_clear_flag(r, RSB_LOCKS_PURGED);
4277 r_ret = r;
4278 break;
4279 }
c7be761a 4280 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
97a35d1e
DT		 4281 return r_ret;
4282}
4283
4284void dlm_grant_after_purge(struct dlm_ls *ls)
e7fd4179
DT		 4285{
4286 struct dlm_rsb *r;
2b4e926a 4287 int bucket = 0;
e7fd4179 4288
2b4e926a
DT		 4289 while (1) {
4290 r = find_purged_rsb(ls, bucket);
4291 if (!r) {
4292 if (bucket == ls->ls_rsbtbl_size - 1)
4293 break;
4294 bucket++;
97a35d1e 4295 continue;
2b4e926a 4296 }
97a35d1e
DT		 4297 lock_rsb(r);
4298 if (is_master(r)) {
4299 grant_pending_locks(r);
4300 confirm_master(r, 0);
e7fd4179 4301 }
97a35d1e
DT		 4302 unlock_rsb(r);
4303 put_rsb(r);
2b4e926a 4304 schedule();
e7fd4179 4305 }
e7fd4179
DT		 4306}
4307
4308static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
4309 uint32_t remid)
4310{
4311 struct dlm_lkb *lkb;
4312
4313 list_for_each_entry(lkb, head, lkb_statequeue) {
4314 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
4315 return lkb;
4316 }
4317 return NULL;
4318}
4319
4320static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
4321 uint32_t remid)
4322{
4323 struct dlm_lkb *lkb;
4324
4325 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
4326 if (lkb)
4327 return lkb;
4328 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
4329 if (lkb)
4330 return lkb;
4331 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
4332 if (lkb)
4333 return lkb;
4334 return NULL;
4335}
4336
ae773d0b 4337/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4338static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
4339 struct dlm_rsb *r, struct dlm_rcom *rc)
4340{
4341 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 4342
4343 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 4344 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
4345 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
4346 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
4347 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 4348 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 4349 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 4350 lkb->lkb_rqmode = rl->rl_rqmode;
4351 lkb->lkb_grmode = rl->rl_grmode;
4352 /* don't set lkb_status because add_lkb wants to itself */
4353
e5dae548
DT		 4354 lkb->lkb_bastfn = (rl->rl_asts & AST_BAST) ? &fake_bastfn : NULL;
4355 lkb->lkb_astfn = (rl->rl_asts & AST_COMP) ? &fake_astfn : NULL;
e7fd4179 4356
e7fd4179 4357 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 4358 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
4359 sizeof(struct rcom_lock);
4360 if (lvblen > ls->ls_lvblen)
4361 return -EINVAL;
52bda2b5 4362 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 4363 if (!lkb->lkb_lvbptr)
4364 return -ENOMEM;
e7fd4179
DT		 4365 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
4366 }
4367
4368 /* Conversions between PR and CW (middle modes) need special handling.
4369 The real granted mode of these converting locks cannot be determined
4370 until all locks have been rebuilt on the rsb (recover_conversion) */
4371
163a1859
AV		 4372 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
4373 middle_conversion(lkb)) {
e7fd4179
DT		 4374 rl->rl_status = DLM_LKSTS_CONVERT;
4375 lkb->lkb_grmode = DLM_LOCK_IV;
4376 rsb_set_flag(r, RSB_RECOVER_CONVERT);
4377 }
4378
4379 return 0;
4380}
4381
4382/* This lkb may have been recovered in a previous aborted recovery so we need
4383 to check if the rsb already has an lkb with the given remote nodeid/lkid.
4384 If so we just send back a standard reply. If not, we create a new lkb with
4385 the given values and send back our lkid. We send back our lkid by sending
4386 back the rcom_lock struct we got but with the remid field filled in. */
4387
ae773d0b 4388/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4389int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4390{
4391 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4392 struct dlm_rsb *r;
4393 struct dlm_lkb *lkb;
4394 int error;
4395
4396 if (rl->rl_parent_lkid) {
4397 error = -EOPNOTSUPP;
4398 goto out;
4399 }
4400
163a1859
AV		 4401 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
4402 R_MASTER, &r);
e7fd4179
DT		 4403 if (error)
4404 goto out;
4405
4406 lock_rsb(r);
4407
163a1859 4408 lkb = search_remid(r, rc->rc_header.h_nodeid, le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4409 if (lkb) {
4410 error = -EEXIST;
4411 goto out_remid;
4412 }
4413
4414 error = create_lkb(ls, &lkb);
4415 if (error)
4416 goto out_unlock;
4417
4418 error = receive_rcom_lock_args(ls, lkb, r, rc);
4419 if (error) {
b3f58d8f 4420 __put_lkb(ls, lkb);
e7fd4179
DT		 4421 goto out_unlock;
4422 }
4423
4424 attach_lkb(r, lkb);
4425 add_lkb(r, lkb, rl->rl_status);
4426 error = 0;
4427
4428 out_remid:
4429 /* this is the new value returned to the lock holder for
4430 saving in its process-copy lkb */
163a1859 4431 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179
DT		 4432
4433 out_unlock:
4434 unlock_rsb(r);
4435 put_rsb(r);
4436 out:
4437 if (error)
163a1859
AV		 4438 log_debug(ls, "recover_master_copy %d %x", error,
4439 le32_to_cpu(rl->rl_lkid));
4440 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 4441 return error;
4442}
4443
ae773d0b 4444/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4445int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4446{
4447 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4448 struct dlm_rsb *r;
4449 struct dlm_lkb *lkb;
4450 int error;
4451
163a1859 4452 error = find_lkb(ls, le32_to_cpu(rl->rl_lkid), &lkb);
e7fd4179 4453 if (error) {
163a1859
AV		 4454 log_error(ls, "recover_process_copy no lkid %x",
4455 le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4456 return error;
4457 }
4458
4459 DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
4460
163a1859 4461 error = le32_to_cpu(rl->rl_result);
e7fd4179
DT		 4462
4463 r = lkb->lkb_resource;
4464 hold_rsb(r);
4465 lock_rsb(r);
4466
4467 switch (error) {
dc200a88
DT		 4468 case -EBADR:
4469 /* There's a chance the new master received our lock before
4470 dlm_recover_master_reply(), this wouldn't happen if we did
4471 a barrier between recover_masters and recover_locks. */
4472 log_debug(ls, "master copy not ready %x r %lx %s", lkb->lkb_id,
4473 (unsigned long)r, r->res_name);
4474 dlm_send_rcom_lock(r, lkb);
4475 goto out;
e7fd4179
DT		 4476 case -EEXIST:
4477 log_debug(ls, "master copy exists %x", lkb->lkb_id);
4478 /* fall through */
4479 case 0:
163a1859 4480 lkb->lkb_remid = le32_to_cpu(rl->rl_remid);
e7fd4179
DT		 4481 break;
4482 default:
4483 log_error(ls, "dlm_recover_process_copy unknown error %d %x",
4484 error, lkb->lkb_id);
4485 }
4486
4487 /* an ack for dlm_recover_locks() which waits for replies from
4488 all the locks it sends to new masters */
4489 dlm_recovered_lock(r);
dc200a88 4490 out:
e7fd4179
DT		 4491 unlock_rsb(r);
4492 put_rsb(r);
b3f58d8f 4493 dlm_put_lkb(lkb);
e7fd4179
DT		 4494
4495 return 0;
4496}
4497
597d0cae
DT		 4498int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
4499 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 4500 unsigned long timeout_cs)
597d0cae
DT		 4501{
4502 struct dlm_lkb *lkb;
4503 struct dlm_args args;
4504 int error;
4505
85e86edf 4506 dlm_lock_recovery(ls);
597d0cae
DT		 4507
4508 error = create_lkb(ls, &lkb);
4509 if (error) {
4510 kfree(ua);
4511 goto out;
4512 }
4513
4514 if (flags & DLM_LKF_VALBLK) {
62a0f623 4515 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_KERNEL);
597d0cae
DT		 4516 if (!ua->lksb.sb_lvbptr) {
4517 kfree(ua);
4518 __put_lkb(ls, lkb);
4519 error = -ENOMEM;
4520 goto out;
4521 }
4522 }
4523
52bda2b5 4524 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 4525 When DLM_IFL_USER is set, the dlm knows that this is a userspace
4526 lock and that lkb_astparam is the dlm_user_args structure. */
4527
d7db923e 4528 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 4529 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 4530 lkb->lkb_flags |= DLM_IFL_USER;
4531 ua->old_mode = DLM_LOCK_IV;
4532
4533 if (error) {
4534 __put_lkb(ls, lkb);
4535 goto out;
4536 }
4537
4538 error = request_lock(ls, lkb, name, namelen, &args);
4539
4540 switch (error) {
4541 case 0:
4542 break;
4543 case -EINPROGRESS:
4544 error = 0;
4545 break;
4546 case -EAGAIN:
4547 error = 0;
4548 /* fall through */
4549 default:
4550 __put_lkb(ls, lkb);
4551 goto out;
4552 }
4553
4554 /* add this new lkb to the per-process list of locks */
4555 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 4556 hold_lkb(lkb);
597d0cae
DT		 4557 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
4558 spin_unlock(&ua->proc->locks_spin);
4559 out:
85e86edf 4560 dlm_unlock_recovery(ls);
597d0cae
DT		 4561 return error;
4562}
4563
4564int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 4565 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
4566 unsigned long timeout_cs)
597d0cae
DT		 4567{
4568 struct dlm_lkb *lkb;
4569 struct dlm_args args;
4570 struct dlm_user_args *ua;
4571 int error;
4572
85e86edf 4573 dlm_lock_recovery(ls);
597d0cae
DT		 4574
4575 error = find_lkb(ls, lkid, &lkb);
4576 if (error)
4577 goto out;
4578
4579 /* user can change the params on its lock when it converts it, or
4580 add an lvb that didn't exist before */
4581
d292c0cc 4582 ua = lkb->lkb_ua;
597d0cae
DT		 4583
4584 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
62a0f623 4585 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_KERNEL);
597d0cae
DT		 4586 if (!ua->lksb.sb_lvbptr) {
4587 error = -ENOMEM;
4588 goto out_put;
4589 }
4590 }
4591 if (lvb_in && ua->lksb.sb_lvbptr)
4592 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
4593
d7db923e 4594 ua->xid = ua_tmp->xid;
597d0cae
DT		 4595 ua->castparam = ua_tmp->castparam;
4596 ua->castaddr = ua_tmp->castaddr;
4597 ua->bastparam = ua_tmp->bastparam;
4598 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 4599 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4600 ua->old_mode = lkb->lkb_grmode;
4601
d7db923e 4602 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 4603 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 4604 if (error)
4605 goto out_put;
4606
4607 error = convert_lock(ls, lkb, &args);
4608
c85d65e9 4609 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 4610 error = 0;
4611 out_put:
4612 dlm_put_lkb(lkb);
4613 out:
85e86edf 4614 dlm_unlock_recovery(ls);
597d0cae
DT		 4615 kfree(ua_tmp);
4616 return error;
4617}
4618
4619int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4620 uint32_t flags, uint32_t lkid, char *lvb_in)
4621{
4622 struct dlm_lkb *lkb;
4623 struct dlm_args args;
4624 struct dlm_user_args *ua;
4625 int error;
4626
85e86edf 4627 dlm_lock_recovery(ls);
597d0cae
DT		 4628
4629 error = find_lkb(ls, lkid, &lkb);
4630 if (error)
4631 goto out;
4632
d292c0cc 4633 ua = lkb->lkb_ua;
597d0cae
DT		 4634
4635 if (lvb_in && ua->lksb.sb_lvbptr)
4636 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 4637 if (ua_tmp->castparam)
4638 ua->castparam = ua_tmp->castparam;
cc346d55 4639 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4640
4641 error = set_unlock_args(flags, ua, &args);
4642 if (error)
4643 goto out_put;
4644
4645 error = unlock_lock(ls, lkb, &args);
4646
4647 if (error == -DLM_EUNLOCK)
4648 error = 0;
ef0c2bb0
DT		 4649 /* from validate_unlock_args() */
4650 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
4651 error = 0;
597d0cae
DT		 4652 if (error)
4653 goto out_put;
4654
4655 spin_lock(&ua->proc->locks_spin);
a1bc86e6
DT		 4656 /* dlm_user_add_ast() may have already taken lkb off the proc list */
4657 if (!list_empty(&lkb->lkb_ownqueue))
4658 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 4659 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 4660 out_put:
4661 dlm_put_lkb(lkb);
4662 out:
85e86edf 4663 dlm_unlock_recovery(ls);
ef0c2bb0 4664 kfree(ua_tmp);
597d0cae
DT		 4665 return error;
4666}
4667
4668int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4669 uint32_t flags, uint32_t lkid)
4670{
4671 struct dlm_lkb *lkb;
4672 struct dlm_args args;
4673 struct dlm_user_args *ua;
4674 int error;
4675
85e86edf 4676 dlm_lock_recovery(ls);
597d0cae
DT		 4677
4678 error = find_lkb(ls, lkid, &lkb);
4679 if (error)
4680 goto out;
4681
d292c0cc 4682 ua = lkb->lkb_ua;
b434eda6
PC		 4683 if (ua_tmp->castparam)
4684 ua->castparam = ua_tmp->castparam;
c059f70e 4685 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4686
4687 error = set_unlock_args(flags, ua, &args);
4688 if (error)
4689 goto out_put;
4690
4691 error = cancel_lock(ls, lkb, &args);
4692
4693 if (error == -DLM_ECANCEL)
4694 error = 0;
ef0c2bb0
DT		 4695 /* from validate_unlock_args() */
4696 if (error == -EBUSY)
4697 error = 0;
597d0cae
DT		 4698 out_put:
4699 dlm_put_lkb(lkb);
4700 out:
85e86edf 4701 dlm_unlock_recovery(ls);
ef0c2bb0 4702 kfree(ua_tmp);
597d0cae
DT		 4703 return error;
4704}
4705
8b4021fa
DT		 4706int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
4707{
4708 struct dlm_lkb *lkb;
4709 struct dlm_args args;
4710 struct dlm_user_args *ua;
4711 struct dlm_rsb *r;
4712 int error;
4713
4714 dlm_lock_recovery(ls);
4715
4716 error = find_lkb(ls, lkid, &lkb);
4717 if (error)
4718 goto out;
4719
d292c0cc 4720 ua = lkb->lkb_ua;
8b4021fa
DT		 4721
4722 error = set_unlock_args(flags, ua, &args);
4723 if (error)
4724 goto out_put;
4725
4726 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
4727
4728 r = lkb->lkb_resource;
4729 hold_rsb(r);
4730 lock_rsb(r);
4731
4732 error = validate_unlock_args(lkb, &args);
4733 if (error)
4734 goto out_r;
4735 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
4736
4737 error = _cancel_lock(r, lkb);
4738 out_r:
4739 unlock_rsb(r);
4740 put_rsb(r);
4741
4742 if (error == -DLM_ECANCEL)
4743 error = 0;
4744 /* from validate_unlock_args() */
4745 if (error == -EBUSY)
4746 error = 0;
4747 out_put:
4748 dlm_put_lkb(lkb);
4749 out:
4750 dlm_unlock_recovery(ls);
4751 return error;
4752}
4753
ef0c2bb0
DT		 4754/* lkb's that are removed from the waiters list by revert are just left on the
4755 orphans list with the granted orphan locks, to be freed by purge */
4756
597d0cae
DT		 4757static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4758{
ef0c2bb0
DT		 4759 struct dlm_args args;
4760 int error;
597d0cae 4761
ef0c2bb0
DT		 4762 hold_lkb(lkb);
4763 mutex_lock(&ls->ls_orphans_mutex);
4764 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
4765 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 4766
d292c0cc 4767 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 4768
4769 error = cancel_lock(ls, lkb, &args);
4770 if (error == -DLM_ECANCEL)
4771 error = 0;
4772 return error;
597d0cae
DT		 4773}
4774
4775/* The force flag allows the unlock to go ahead even if the lkb isn't granted.
4776 Regardless of what rsb queue the lock is on, it's removed and freed. */
4777
4778static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4779{
597d0cae
DT		 4780 struct dlm_args args;
4781 int error;
4782
d292c0cc 4783 set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
597d0cae
DT		 4784
4785 error = unlock_lock(ls, lkb, &args);
4786 if (error == -DLM_EUNLOCK)
4787 error = 0;
4788 return error;
4789}
4790
ef0c2bb0
DT		 4791/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
4792 (which does lock_rsb) due to deadlock with receiving a message that does
4793 lock_rsb followed by dlm_user_add_ast() */
4794
4795static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
4796 struct dlm_user_proc *proc)
4797{
4798 struct dlm_lkb *lkb = NULL;
4799
4800 mutex_lock(&ls->ls_clear_proc_locks);
4801 if (list_empty(&proc->locks))
4802 goto out;
4803
4804 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
4805 list_del_init(&lkb->lkb_ownqueue);
4806
4807 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
4808 lkb->lkb_flags |= DLM_IFL_ORPHAN;
4809 else
4810 lkb->lkb_flags |= DLM_IFL_DEAD;
4811 out:
4812 mutex_unlock(&ls->ls_clear_proc_locks);
4813 return lkb;
4814}
4815
597d0cae
DT		 4816/* The ls_clear_proc_locks mutex protects against dlm_user_add_asts() which
4817 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
4818 which we clear here. */
4819
4820/* proc CLOSING flag is set so no more device_reads should look at proc->asts
4821 list, and no more device_writes should add lkb's to proc->locks list; so we
4822 shouldn't need to take asts_spin or locks_spin here. this assumes that
4823 device reads/writes/closes are serialized -- FIXME: we may need to serialize
4824 them ourself. */
4825
4826void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
4827{
4828 struct dlm_lkb *lkb, *safe;
4829
85e86edf 4830 dlm_lock_recovery(ls);
597d0cae 4831
ef0c2bb0
DT		 4832 while (1) {
4833 lkb = del_proc_lock(ls, proc);
4834 if (!lkb)
4835 break;
84d8cd69 4836 del_timeout(lkb);
ef0c2bb0 4837 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 4838 orphan_proc_lock(ls, lkb);
ef0c2bb0 4839 else
597d0cae 4840 unlock_proc_lock(ls, lkb);
597d0cae
DT		 4841
4842 /* this removes the reference for the proc->locks list
4843 added by dlm_user_request, it may result in the lkb
4844 being freed */
4845
4846 dlm_put_lkb(lkb);
4847 }
a1bc86e6 4848
ef0c2bb0
DT		 4849 mutex_lock(&ls->ls_clear_proc_locks);
4850
a1bc86e6
DT		 4851 /* in-progress unlocks */
4852 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
4853 list_del_init(&lkb->lkb_ownqueue);
4854 lkb->lkb_flags |= DLM_IFL_DEAD;
4855 dlm_put_lkb(lkb);
4856 }
4857
4858 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
8a358ca8 4859 lkb->lkb_ast_type = 0;
a1bc86e6
DT		 4860 list_del(&lkb->lkb_astqueue);
4861 dlm_put_lkb(lkb);
4862 }
4863
597d0cae 4864 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 4865 dlm_unlock_recovery(ls);
597d0cae 4866}
a1bc86e6 4867
8499137d
DT		 4868static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
4869{
4870 struct dlm_lkb *lkb, *safe;
4871
4872 while (1) {
4873 lkb = NULL;
4874 spin_lock(&proc->locks_spin);
4875 if (!list_empty(&proc->locks)) {
4876 lkb = list_entry(proc->locks.next, struct dlm_lkb,
4877 lkb_ownqueue);
4878 list_del_init(&lkb->lkb_ownqueue);
4879 }
4880 spin_unlock(&proc->locks_spin);
4881
4882 if (!lkb)
4883 break;
4884
4885 lkb->lkb_flags |= DLM_IFL_DEAD;
4886 unlock_proc_lock(ls, lkb);
4887 dlm_put_lkb(lkb); /* ref from proc->locks list */
4888 }
4889
4890 spin_lock(&proc->locks_spin);
4891 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
4892 list_del_init(&lkb->lkb_ownqueue);
4893 lkb->lkb_flags |= DLM_IFL_DEAD;
4894 dlm_put_lkb(lkb);
4895 }
4896 spin_unlock(&proc->locks_spin);
4897
4898 spin_lock(&proc->asts_spin);
4899 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
4900 list_del(&lkb->lkb_astqueue);
4901 dlm_put_lkb(lkb);
4902 }
4903 spin_unlock(&proc->asts_spin);
4904}
4905
4906/* pid of 0 means purge all orphans */
4907
4908static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
4909{
4910 struct dlm_lkb *lkb, *safe;
4911
4912 mutex_lock(&ls->ls_orphans_mutex);
4913 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
4914 if (pid && lkb->lkb_ownpid != pid)
4915 continue;
4916 unlock_proc_lock(ls, lkb);
4917 list_del_init(&lkb->lkb_ownqueue);
4918 dlm_put_lkb(lkb);
4919 }
4920 mutex_unlock(&ls->ls_orphans_mutex);
4921}
4922
4923static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
4924{
4925 struct dlm_message *ms;
4926 struct dlm_mhandle *mh;
4927 int error;
4928
4929 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
4930 DLM_MSG_PURGE, &ms, &mh);
4931 if (error)
4932 return error;
4933 ms->m_nodeid = nodeid;
4934 ms->m_pid = pid;
4935
4936 return send_message(mh, ms);
4937}
4938
4939int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
4940 int nodeid, int pid)
4941{
4942 int error = 0;
4943
4944 if (nodeid != dlm_our_nodeid()) {
4945 error = send_purge(ls, nodeid, pid);
4946 } else {
85e86edf 4947 dlm_lock_recovery(ls);
8499137d
DT		 4948 if (pid == current->pid)
4949 purge_proc_locks(ls, proc);
4950 else
4951 do_purge(ls, nodeid, pid);
85e86edf 4952 dlm_unlock_recovery(ls);
8499137d
DT		 4953 }
4954 return error;
4955}
4956
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