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1/******************************************************************************
2*******************************************************************************
3**
4** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
5**
6** This copyrighted material is made available to anyone wishing to use,
7** modify, copy, or redistribute it subject to the terms and conditions
8** of the GNU General Public License v.2.
9**
10*******************************************************************************
11******************************************************************************/
12
13/* Central locking logic has four stages:
14
15 dlm_lock()
16 dlm_unlock()
17
18 request_lock(ls, lkb)
19 convert_lock(ls, lkb)
20 unlock_lock(ls, lkb)
21 cancel_lock(ls, lkb)
22
23 _request_lock(r, lkb)
24 _convert_lock(r, lkb)
25 _unlock_lock(r, lkb)
26 _cancel_lock(r, lkb)
27
28 do_request(r, lkb)
29 do_convert(r, lkb)
30 do_unlock(r, lkb)
31 do_cancel(r, lkb)
32
33 Stage 1 (lock, unlock) is mainly about checking input args and
34 splitting into one of the four main operations:
35
36 dlm_lock = request_lock
37 dlm_lock+CONVERT = convert_lock
38 dlm_unlock = unlock_lock
39 dlm_unlock+CANCEL = cancel_lock
40
41 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
42 provided to the next stage.
43
44 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
45 When remote, it calls send_xxxx(), when local it calls do_xxxx().
46
47 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
48 given rsb and lkb and queues callbacks.
49
50 For remote operations, send_xxxx() results in the corresponding do_xxxx()
51 function being executed on the remote node. The connecting send/receive
52 calls on local (L) and remote (R) nodes:
53
54 L: send_xxxx() -> R: receive_xxxx()
55 R: do_xxxx()
56 L: receive_xxxx_reply() <- R: send_xxxx_reply()
57*/
58#include <linux/types.h>
59#include <linux/rbtree.h>
60#include <linux/slab.h>
61#include "dlm_internal.h"
62#include <linux/dlm_device.h>
63#include "memory.h"
64#include "lowcomms.h"
65#include "requestqueue.h"
66#include "util.h"
67#include "dir.h"
68#include "member.h"
69#include "lockspace.h"
70#include "ast.h"
71#include "lock.h"
72#include "rcom.h"
73#include "recover.h"
74#include "lvb_table.h"
75#include "user.h"
76#include "config.h"
77
78static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
82static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
83static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
84static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
85static int send_remove(struct dlm_rsb *r);
86static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
87static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
88static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
89 struct dlm_message *ms);
90static int receive_extralen(struct dlm_message *ms);
91static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
92static void del_timeout(struct dlm_lkb *lkb);
93static void toss_rsb(struct kref *kref);
94
95/*
96 * Lock compatibilty matrix - thanks Steve
97 * UN = Unlocked state. Not really a state, used as a flag
98 * PD = Padding. Used to make the matrix a nice power of two in size
99 * Other states are the same as the VMS DLM.
100 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
101 */
102
103static const int __dlm_compat_matrix[8][8] = {
104 /* UN NL CR CW PR PW EX PD */
105 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
106 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
107 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
108 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
109 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
110 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
111 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
112 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
113};
114
115/*
116 * This defines the direction of transfer of LVB data.
117 * Granted mode is the row; requested mode is the column.
118 * Usage: matrix[grmode+1][rqmode+1]
119 * 1 = LVB is returned to the caller
120 * 0 = LVB is written to the resource
121 * -1 = nothing happens to the LVB
122 */
123
124const int dlm_lvb_operations[8][8] = {
125 /* UN NL CR CW PR PW EX PD*/
126 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
127 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
128 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
129 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
130 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
131 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
132 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
133 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
134};
135
136#define modes_compat(gr, rq) \
137 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
138
139int dlm_modes_compat(int mode1, int mode2)
140{
141 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
142}
143
144/*
145 * Compatibility matrix for conversions with QUECVT set.
146 * Granted mode is the row; requested mode is the column.
147 * Usage: matrix[grmode+1][rqmode+1]
148 */
149
150static const int __quecvt_compat_matrix[8][8] = {
151 /* UN NL CR CW PR PW EX PD */
152 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
153 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
154 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
155 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
156 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
157 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
158 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
159 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
160};
161
162void dlm_print_lkb(struct dlm_lkb *lkb)
163{
164 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
165 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
166 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
167 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
168 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
169 (unsigned long long)lkb->lkb_recover_seq);
170}
171
172static void dlm_print_rsb(struct dlm_rsb *r)
173{
174 printk(KERN_ERR "rsb: nodeid %d master %d dir %d flags %lx first %x "
175 "rlc %d name %s\n",
176 r->res_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
177 r->res_flags, r->res_first_lkid, r->res_recover_locks_count,
178 r->res_name);
179}
180
181void dlm_dump_rsb(struct dlm_rsb *r)
182{
183 struct dlm_lkb *lkb;
184
185 dlm_print_rsb(r);
186
187 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
188 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
189 printk(KERN_ERR "rsb lookup list\n");
190 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
191 dlm_print_lkb(lkb);
192 printk(KERN_ERR "rsb grant queue:\n");
193 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
194 dlm_print_lkb(lkb);
195 printk(KERN_ERR "rsb convert queue:\n");
196 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
197 dlm_print_lkb(lkb);
198 printk(KERN_ERR "rsb wait queue:\n");
199 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
200 dlm_print_lkb(lkb);
201}
202
203/* Threads cannot use the lockspace while it's being recovered */
204
205static inline void dlm_lock_recovery(struct dlm_ls *ls)
206{
207 down_read(&ls->ls_in_recovery);
208}
209
210void dlm_unlock_recovery(struct dlm_ls *ls)
211{
212 up_read(&ls->ls_in_recovery);
213}
214
215int dlm_lock_recovery_try(struct dlm_ls *ls)
216{
217 return down_read_trylock(&ls->ls_in_recovery);
218}
219
220static inline int can_be_queued(struct dlm_lkb *lkb)
221{
222 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
223}
224
225static inline int force_blocking_asts(struct dlm_lkb *lkb)
226{
227 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
228}
229
230static inline int is_demoted(struct dlm_lkb *lkb)
231{
232 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
233}
234
235static inline int is_altmode(struct dlm_lkb *lkb)
236{
237 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
238}
239
240static inline int is_granted(struct dlm_lkb *lkb)
241{
242 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
243}
244
245static inline int is_remote(struct dlm_rsb *r)
246{
247 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
248 return !!r->res_nodeid;
249}
250
251static inline int is_process_copy(struct dlm_lkb *lkb)
252{
253 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
254}
255
256static inline int is_master_copy(struct dlm_lkb *lkb)
257{
258 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
259}
260
261static inline int middle_conversion(struct dlm_lkb *lkb)
262{
263 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
264 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
265 return 1;
266 return 0;
267}
268
269static inline int down_conversion(struct dlm_lkb *lkb)
270{
271 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
272}
273
274static inline int is_overlap_unlock(struct dlm_lkb *lkb)
275{
276 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
277}
278
279static inline int is_overlap_cancel(struct dlm_lkb *lkb)
280{
281 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
282}
283
284static inline int is_overlap(struct dlm_lkb *lkb)
285{
286 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
287 DLM_IFL_OVERLAP_CANCEL));
288}
289
290static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
291{
292 if (is_master_copy(lkb))
293 return;
294
295 del_timeout(lkb);
296
297 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
298
299 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
300 timeout caused the cancel then return -ETIMEDOUT */
301 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
302 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
303 rv = -ETIMEDOUT;
304 }
305
306 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
307 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
308 rv = -EDEADLK;
309 }
310
311 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
312}
313
314static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
315{
316 queue_cast(r, lkb,
317 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
318}
319
320static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
321{
322 if (is_master_copy(lkb)) {
323 send_bast(r, lkb, rqmode);
324 } else {
325 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
326 }
327}
328
329/*
330 * Basic operations on rsb's and lkb's
331 */
332
333/* This is only called to add a reference when the code already holds
334 a valid reference to the rsb, so there's no need for locking. */
335
336static inline void hold_rsb(struct dlm_rsb *r)
337{
338 kref_get(&r->res_ref);
339}
340
341void dlm_hold_rsb(struct dlm_rsb *r)
342{
343 hold_rsb(r);
344}
345
346/* When all references to the rsb are gone it's transferred to
347 the tossed list for later disposal. */
348
349static void put_rsb(struct dlm_rsb *r)
350{
351 struct dlm_ls *ls = r->res_ls;
352 uint32_t bucket = r->res_bucket;
353
354 spin_lock(&ls->ls_rsbtbl[bucket].lock);
355 kref_put(&r->res_ref, toss_rsb);
356 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
357}
358
359void dlm_put_rsb(struct dlm_rsb *r)
360{
361 put_rsb(r);
362}
363
364static int pre_rsb_struct(struct dlm_ls *ls)
365{
366 struct dlm_rsb *r1, *r2;
367 int count = 0;
368
369 spin_lock(&ls->ls_new_rsb_spin);
370 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
371 spin_unlock(&ls->ls_new_rsb_spin);
372 return 0;
373 }
374 spin_unlock(&ls->ls_new_rsb_spin);
375
376 r1 = dlm_allocate_rsb(ls);
377 r2 = dlm_allocate_rsb(ls);
378
379 spin_lock(&ls->ls_new_rsb_spin);
380 if (r1) {
381 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
382 ls->ls_new_rsb_count++;
383 }
384 if (r2) {
385 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
386 ls->ls_new_rsb_count++;
387 }
388 count = ls->ls_new_rsb_count;
389 spin_unlock(&ls->ls_new_rsb_spin);
390
391 if (!count)
392 return -ENOMEM;
393 return 0;
394}
395
396/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
397 unlock any spinlocks, go back and call pre_rsb_struct again.
398 Otherwise, take an rsb off the list and return it. */
399
400static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
401 struct dlm_rsb **r_ret)
402{
403 struct dlm_rsb *r;
404 int count;
405
406 spin_lock(&ls->ls_new_rsb_spin);
407 if (list_empty(&ls->ls_new_rsb)) {
408 count = ls->ls_new_rsb_count;
409 spin_unlock(&ls->ls_new_rsb_spin);
410 log_debug(ls, "find_rsb retry %d %d %s",
411 count, dlm_config.ci_new_rsb_count, name);
412 return -EAGAIN;
413 }
414
415 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
416 list_del(&r->res_hashchain);
417 /* Convert the empty list_head to a NULL rb_node for tree usage: */
418 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
419 ls->ls_new_rsb_count--;
420 spin_unlock(&ls->ls_new_rsb_spin);
421
422 r->res_ls = ls;
423 r->res_length = len;
424 memcpy(r->res_name, name, len);
425 mutex_init(&r->res_mutex);
426
427 INIT_LIST_HEAD(&r->res_lookup);
428 INIT_LIST_HEAD(&r->res_grantqueue);
429 INIT_LIST_HEAD(&r->res_convertqueue);
430 INIT_LIST_HEAD(&r->res_waitqueue);
431 INIT_LIST_HEAD(&r->res_root_list);
432 INIT_LIST_HEAD(&r->res_recover_list);
433
434 *r_ret = r;
435 return 0;
436}
437
438static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
439{
440 char maxname[DLM_RESNAME_MAXLEN];
441
442 memset(maxname, 0, DLM_RESNAME_MAXLEN);
443 memcpy(maxname, name, nlen);
444 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
445}
446
447int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
448 struct dlm_rsb **r_ret)
449{
450 struct rb_node *node = tree->rb_node;
451 struct dlm_rsb *r;
452 int rc;
453
454 while (node) {
455 r = rb_entry(node, struct dlm_rsb, res_hashnode);
456 rc = rsb_cmp(r, name, len);
457 if (rc < 0)
458 node = node->rb_left;
459 else if (rc > 0)
460 node = node->rb_right;
461 else
462 goto found;
463 }
464 *r_ret = NULL;
465 return -EBADR;
466
467 found:
468 *r_ret = r;
469 return 0;
470}
471
472static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
473{
474 struct rb_node **newn = &tree->rb_node;
475 struct rb_node *parent = NULL;
476 int rc;
477
478 while (*newn) {
479 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
480 res_hashnode);
481
482 parent = *newn;
483 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
484 if (rc < 0)
485 newn = &parent->rb_left;
486 else if (rc > 0)
487 newn = &parent->rb_right;
488 else {
489 log_print("rsb_insert match");
490 dlm_dump_rsb(rsb);
491 dlm_dump_rsb(cur);
492 return -EEXIST;
493 }
494 }
495
496 rb_link_node(&rsb->res_hashnode, parent, newn);
497 rb_insert_color(&rsb->res_hashnode, tree);
498 return 0;
499}
500
501/*
502 * Find rsb in rsbtbl and potentially create/add one
503 *
504 * Delaying the release of rsb's has a similar benefit to applications keeping
505 * NL locks on an rsb, but without the guarantee that the cached master value
506 * will still be valid when the rsb is reused. Apps aren't always smart enough
507 * to keep NL locks on an rsb that they may lock again shortly; this can lead
508 * to excessive master lookups and removals if we don't delay the release.
509 *
510 * Searching for an rsb means looking through both the normal list and toss
511 * list. When found on the toss list the rsb is moved to the normal list with
512 * ref count of 1; when found on normal list the ref count is incremented.
513 *
514 * rsb's on the keep list are being used locally and refcounted.
515 * rsb's on the toss list are not being used locally, and are not refcounted.
516 *
517 * The toss list rsb's were either
518 * - previously used locally but not any more (were on keep list, then
519 * moved to toss list when last refcount dropped)
520 * - created and put on toss list as a directory record for a lookup
521 * (we are the dir node for the res, but are not using the res right now,
522 * but some other node is)
523 *
524 * The purpose of find_rsb() is to return a refcounted rsb for local use.
525 * So, if the given rsb is on the toss list, it is moved to the keep list
526 * before being returned.
527 *
528 * toss_rsb() happens when all local usage of the rsb is done, i.e. no
529 * more refcounts exist, so the rsb is moved from the keep list to the
530 * toss list.
531 *
532 * rsb's on both keep and toss lists are used for doing a name to master
533 * lookups. rsb's that are in use locally (and being refcounted) are on
534 * the keep list, rsb's that are not in use locally (not refcounted) and
535 * only exist for name/master lookups are on the toss list.
536 *
537 * rsb's on the toss list who's dir_nodeid is not local can have stale
538 * name/master mappings. So, remote requests on such rsb's can potentially
539 * return with an error, which means the mapping is stale and needs to
540 * be updated with a new lookup. (The idea behind MASTER UNCERTAIN and
541 * first_lkid is to keep only a single outstanding request on an rsb
542 * while that rsb has a potentially stale master.)
543 */
544
545static int find_rsb_dir(struct dlm_ls *ls, char *name, int len,
546 uint32_t hash, uint32_t b,
547 int dir_nodeid, int from_nodeid,
548 unsigned int flags, struct dlm_rsb **r_ret)
549{
550 struct dlm_rsb *r = NULL;
551 int our_nodeid = dlm_our_nodeid();
552 int from_local = 0;
553 int from_other = 0;
554 int from_dir = 0;
555 int create = 0;
556 int error;
557
558 if (flags & R_RECEIVE_REQUEST) {
559 if (from_nodeid == dir_nodeid)
560 from_dir = 1;
561 else
562 from_other = 1;
563 } else if (flags & R_REQUEST) {
564 from_local = 1;
565 }
566
567 /*
568 * flags & R_RECEIVE_RECOVER is from dlm_recover_master_copy, so
569 * from_nodeid has sent us a lock in dlm_recover_locks, believing
570 * we're the new master. Our local recovery may not have set
571 * res_master_nodeid to our_nodeid yet, so allow either. Don't
572 * create the rsb; dlm_recover_process_copy() will handle EBADR
573 * by resending.
574 *
575 * If someone sends us a request, we are the dir node, and we do
576 * not find the rsb anywhere, then recreate it. This happens if
577 * someone sends us a request after we have removed/freed an rsb
578 * from our toss list. (They sent a request instead of lookup
579 * because they are using an rsb from their toss list.)
580 */
581
582 if (from_local || from_dir ||
583 (from_other && (dir_nodeid == our_nodeid))) {
584 create = 1;
585 }
586
587 retry:
588 if (create) {
589 error = pre_rsb_struct(ls);
590 if (error < 0)
591 goto out;
592 }
593
594 spin_lock(&ls->ls_rsbtbl[b].lock);
595
596 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
597 if (error)
598 goto do_toss;
599
600 /*
601 * rsb is active, so we can't check master_nodeid without lock_rsb.
602 */
603
604 kref_get(&r->res_ref);
605 error = 0;
606 goto out_unlock;
607
608
609 do_toss:
610 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
611 if (error)
612 goto do_new;
613
614 /*
615 * rsb found inactive (master_nodeid may be out of date unless
616 * we are the dir_nodeid or were the master) No other thread
617 * is using this rsb because it's on the toss list, so we can
618 * look at or update res_master_nodeid without lock_rsb.
619 */
620
621 if ((r->res_master_nodeid != our_nodeid) && from_other) {
622 /* our rsb was not master, and another node (not the dir node)
623 has sent us a request */
624 log_debug(ls, "find_rsb toss from_other %d master %d dir %d %s",
625 from_nodeid, r->res_master_nodeid, dir_nodeid,
626 r->res_name);
627 error = -ENOTBLK;
628 goto out_unlock;
629 }
630
631 if ((r->res_master_nodeid != our_nodeid) && from_dir) {
632 /* don't think this should ever happen */
633 log_error(ls, "find_rsb toss from_dir %d master %d",
634 from_nodeid, r->res_master_nodeid);
635 dlm_print_rsb(r);
636 /* fix it and go on */
637 r->res_master_nodeid = our_nodeid;
638 r->res_nodeid = 0;
639 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
640 r->res_first_lkid = 0;
641 }
642
643 if (from_local && (r->res_master_nodeid != our_nodeid)) {
644 /* Because we have held no locks on this rsb,
645 res_master_nodeid could have become stale. */
646 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
647 r->res_first_lkid = 0;
648 }
649
650 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
651 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
652 goto out_unlock;
653
654
655 do_new:
656 /*
657 * rsb not found
658 */
659
660 if (error == -EBADR && !create)
661 goto out_unlock;
662
663 error = get_rsb_struct(ls, name, len, &r);
664 if (error == -EAGAIN) {
665 spin_unlock(&ls->ls_rsbtbl[b].lock);
666 goto retry;
667 }
668 if (error)
669 goto out_unlock;
670
671 r->res_hash = hash;
672 r->res_bucket = b;
673 r->res_dir_nodeid = dir_nodeid;
674 kref_init(&r->res_ref);
675
676 if (from_dir) {
677 /* want to see how often this happens */
678 log_debug(ls, "find_rsb new from_dir %d recreate %s",
679 from_nodeid, r->res_name);
680 r->res_master_nodeid = our_nodeid;
681 r->res_nodeid = 0;
682 goto out_add;
683 }
684
685 if (from_other && (dir_nodeid != our_nodeid)) {
686 /* should never happen */
687 log_error(ls, "find_rsb new from_other %d dir %d our %d %s",
688 from_nodeid, dir_nodeid, our_nodeid, r->res_name);
689 dlm_free_rsb(r);
690 r = NULL;
691 error = -ENOTBLK;
692 goto out_unlock;
693 }
694
695 if (from_other) {
696 log_debug(ls, "find_rsb new from_other %d dir %d %s",
697 from_nodeid, dir_nodeid, r->res_name);
698 }
699
700 if (dir_nodeid == our_nodeid) {
701 /* When we are the dir nodeid, we can set the master
702 node immediately */
703 r->res_master_nodeid = our_nodeid;
704 r->res_nodeid = 0;
705 } else {
706 /* set_master will send_lookup to dir_nodeid */
707 r->res_master_nodeid = 0;
708 r->res_nodeid = -1;
709 }
710
711 out_add:
712 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
713 out_unlock:
714 spin_unlock(&ls->ls_rsbtbl[b].lock);
715 out:
716 *r_ret = r;
717 return error;
718}
719
720/* During recovery, other nodes can send us new MSTCPY locks (from
721 dlm_recover_locks) before we've made ourself master (in
722 dlm_recover_masters). */
723
724static int find_rsb_nodir(struct dlm_ls *ls, char *name, int len,
725 uint32_t hash, uint32_t b,
726 int dir_nodeid, int from_nodeid,
727 unsigned int flags, struct dlm_rsb **r_ret)
728{
729 struct dlm_rsb *r = NULL;
730 int our_nodeid = dlm_our_nodeid();
731 int recover = (flags & R_RECEIVE_RECOVER);
732 int error;
733
734 retry:
735 error = pre_rsb_struct(ls);
736 if (error < 0)
737 goto out;
738
739 spin_lock(&ls->ls_rsbtbl[b].lock);
740
741 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
742 if (error)
743 goto do_toss;
744
745 /*
746 * rsb is active, so we can't check master_nodeid without lock_rsb.
747 */
748
749 kref_get(&r->res_ref);
750 goto out_unlock;
751
752
753 do_toss:
754 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
755 if (error)
756 goto do_new;
757
758 /*
759 * rsb found inactive. No other thread is using this rsb because
760 * it's on the toss list, so we can look at or update
761 * res_master_nodeid without lock_rsb.
762 */
763
764 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
765 /* our rsb is not master, and another node has sent us a
766 request; this should never happen */
767 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
768 from_nodeid, r->res_master_nodeid, dir_nodeid);
769 dlm_print_rsb(r);
770 error = -ENOTBLK;
771 goto out_unlock;
772 }
773
774 if (!recover && (r->res_master_nodeid != our_nodeid) &&
775 (dir_nodeid == our_nodeid)) {
776 /* our rsb is not master, and we are dir; may as well fix it;
777 this should never happen */
778 log_error(ls, "find_rsb toss our %d master %d dir %d",
779 our_nodeid, r->res_master_nodeid, dir_nodeid);
780 dlm_print_rsb(r);
781 r->res_master_nodeid = our_nodeid;
782 r->res_nodeid = 0;
783 }
784
785 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
786 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
787 goto out_unlock;
788
789
790 do_new:
791 /*
792 * rsb not found
793 */
794
795 error = get_rsb_struct(ls, name, len, &r);
796 if (error == -EAGAIN) {
797 spin_unlock(&ls->ls_rsbtbl[b].lock);
798 goto retry;
799 }
800 if (error)
801 goto out_unlock;
802
803 r->res_hash = hash;
804 r->res_bucket = b;
805 r->res_dir_nodeid = dir_nodeid;
806 r->res_master_nodeid = dir_nodeid;
807 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
808 kref_init(&r->res_ref);
809
810 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
811 out_unlock:
812 spin_unlock(&ls->ls_rsbtbl[b].lock);
813 out:
814 *r_ret = r;
815 return error;
816}
817
818static int find_rsb(struct dlm_ls *ls, char *name, int len, int from_nodeid,
819 unsigned int flags, struct dlm_rsb **r_ret)
820{
821 uint32_t hash, b;
822 int dir_nodeid;
823
824 if (len > DLM_RESNAME_MAXLEN)
825 return -EINVAL;
826
827 hash = jhash(name, len, 0);
828 b = hash & (ls->ls_rsbtbl_size - 1);
829
830 dir_nodeid = dlm_hash2nodeid(ls, hash);
831
832 if (dlm_no_directory(ls))
833 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
834 from_nodeid, flags, r_ret);
835 else
836 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
837 from_nodeid, flags, r_ret);
838}
839
840/* we have received a request and found that res_master_nodeid != our_nodeid,
841 so we need to return an error or make ourself the master */
842
843static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
844 int from_nodeid)
845{
846 if (dlm_no_directory(ls)) {
847 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
848 from_nodeid, r->res_master_nodeid,
849 r->res_dir_nodeid);
850 dlm_print_rsb(r);
851 return -ENOTBLK;
852 }
853
854 if (from_nodeid != r->res_dir_nodeid) {
855 /* our rsb is not master, and another node (not the dir node)
856 has sent us a request. this is much more common when our
857 master_nodeid is zero, so limit debug to non-zero. */
858
859 if (r->res_master_nodeid) {
860 log_debug(ls, "validate master from_other %d master %d "
861 "dir %d first %x %s", from_nodeid,
862 r->res_master_nodeid, r->res_dir_nodeid,
863 r->res_first_lkid, r->res_name);
864 }
865 return -ENOTBLK;
866 } else {
867 /* our rsb is not master, but the dir nodeid has sent us a
868 request; this could happen with master 0 / res_nodeid -1 */
869
870 if (r->res_master_nodeid) {
871 log_error(ls, "validate master from_dir %d master %d "
872 "first %x %s",
873 from_nodeid, r->res_master_nodeid,
874 r->res_first_lkid, r->res_name);
875 }
876
877 r->res_master_nodeid = dlm_our_nodeid();
878 r->res_nodeid = 0;
879 return 0;
880 }
881}
882
883/*
884 * We're the dir node for this res and another node wants to know the
885 * master nodeid. During normal operation (non recovery) this is only
886 * called from receive_lookup(); master lookups when the local node is
887 * the dir node are done by find_rsb().
888 *
889 * normal operation, we are the dir node for a resource
890 * . _request_lock
891 * . set_master
892 * . send_lookup
893 * . receive_lookup
894 * . dlm_master_lookup flags 0
895 *
896 * recover directory, we are rebuilding dir for all resources
897 * . dlm_recover_directory
898 * . dlm_rcom_names
899 * remote node sends back the rsb names it is master of and we are dir of
900 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
901 * we either create new rsb setting remote node as master, or find existing
902 * rsb and set master to be the remote node.
903 *
904 * recover masters, we are finding the new master for resources
905 * . dlm_recover_masters
906 * . recover_master
907 * . dlm_send_rcom_lookup
908 * . receive_rcom_lookup
909 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
910 */
911
912int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, char *name, int len,
913 unsigned int flags, int *r_nodeid, int *result)
914{
915 struct dlm_rsb *r = NULL;
916 uint32_t hash, b;
917 int from_master = (flags & DLM_LU_RECOVER_DIR);
918 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
919 int our_nodeid = dlm_our_nodeid();
920 int dir_nodeid, error, toss_list = 0;
921
922 if (len > DLM_RESNAME_MAXLEN)
923 return -EINVAL;
924
925 if (from_nodeid == our_nodeid) {
926 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
927 our_nodeid, flags);
928 return -EINVAL;
929 }
930
931 hash = jhash(name, len, 0);
932 b = hash & (ls->ls_rsbtbl_size - 1);
933
934 dir_nodeid = dlm_hash2nodeid(ls, hash);
935 if (dir_nodeid != our_nodeid) {
936 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
937 from_nodeid, dir_nodeid, our_nodeid, hash,
938 ls->ls_num_nodes);
939 *r_nodeid = -1;
940 return -EINVAL;
941 }
942
943 retry:
944 error = pre_rsb_struct(ls);
945 if (error < 0)
946 return error;
947
948 spin_lock(&ls->ls_rsbtbl[b].lock);
949 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
950 if (!error) {
951 /* because the rsb is active, we need to lock_rsb before
952 checking/changing re_master_nodeid */
953
954 hold_rsb(r);
955 spin_unlock(&ls->ls_rsbtbl[b].lock);
956 lock_rsb(r);
957 goto found;
958 }
959
960 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
961 if (error)
962 goto not_found;
963
964 /* because the rsb is inactive (on toss list), it's not refcounted
965 and lock_rsb is not used, but is protected by the rsbtbl lock */
966
967 toss_list = 1;
968 found:
969 if (r->res_dir_nodeid != our_nodeid) {
970 /* should not happen, but may as well fix it and carry on */
971 log_error(ls, "dlm_master_lookup res_dir %d our %d %s",
972 r->res_dir_nodeid, our_nodeid, r->res_name);
973 r->res_dir_nodeid = our_nodeid;
974 }
975
976 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
977 /* Recovery uses this function to set a new master when
978 the previous master failed. Setting NEW_MASTER will
979 force dlm_recover_masters to call recover_master on this
980 rsb even though the res_nodeid is no longer removed. */
981
982 r->res_master_nodeid = from_nodeid;
983 r->res_nodeid = from_nodeid;
984 rsb_set_flag(r, RSB_NEW_MASTER);
985
986 if (toss_list) {
987 /* I don't think we should ever find it on toss list. */
988 log_error(ls, "dlm_master_lookup fix_master on toss");
989 dlm_dump_rsb(r);
990 }
991 }
992
993 if (from_master && (r->res_master_nodeid != from_nodeid)) {
994 /* this will happen if from_nodeid became master during
995 a previous recovery cycle, and we aborted the previous
996 cycle before recovering this master value */
997
998 log_limit(ls, "dlm_master_lookup from_master %d "
999 "master_nodeid %d res_nodeid %d first %x %s",
1000 from_nodeid, r->res_master_nodeid, r->res_nodeid,
1001 r->res_first_lkid, r->res_name);
1002
1003 if (r->res_master_nodeid == our_nodeid) {
1004 log_error(ls, "from_master %d our_master", from_nodeid);
1005 dlm_dump_rsb(r);
1006 dlm_send_rcom_lookup_dump(r, from_nodeid);
1007 goto out_found;
1008 }
1009
1010 r->res_master_nodeid = from_nodeid;
1011 r->res_nodeid = from_nodeid;
1012 rsb_set_flag(r, RSB_NEW_MASTER);
1013 }
1014
1015 if (!r->res_master_nodeid) {
1016 /* this will happen if recovery happens while we're looking
1017 up the master for this rsb */
1018
1019 log_debug(ls, "dlm_master_lookup master 0 to %d first %x %s",
1020 from_nodeid, r->res_first_lkid, r->res_name);
1021 r->res_master_nodeid = from_nodeid;
1022 r->res_nodeid = from_nodeid;
1023 }
1024
1025 if (!from_master && !fix_master &&
1026 (r->res_master_nodeid == from_nodeid)) {
1027 /* this can happen when the master sends remove, the dir node
1028 finds the rsb on the keep list and ignores the remove,
1029 and the former master sends a lookup */
1030
1031 log_limit(ls, "dlm_master_lookup from master %d flags %x "
1032 "first %x %s", from_nodeid, flags,
1033 r->res_first_lkid, r->res_name);
1034 }
1035
1036 out_found:
1037 *r_nodeid = r->res_master_nodeid;
1038 if (result)
1039 *result = DLM_LU_MATCH;
1040
1041 if (toss_list) {
1042 r->res_toss_time = jiffies;
1043 /* the rsb was inactive (on toss list) */
1044 spin_unlock(&ls->ls_rsbtbl[b].lock);
1045 } else {
1046 /* the rsb was active */
1047 unlock_rsb(r);
1048 put_rsb(r);
1049 }
1050 return 0;
1051
1052 not_found:
1053 error = get_rsb_struct(ls, name, len, &r);
1054 if (error == -EAGAIN) {
1055 spin_unlock(&ls->ls_rsbtbl[b].lock);
1056 goto retry;
1057 }
1058 if (error)
1059 goto out_unlock;
1060
1061 r->res_hash = hash;
1062 r->res_bucket = b;
1063 r->res_dir_nodeid = our_nodeid;
1064 r->res_master_nodeid = from_nodeid;
1065 r->res_nodeid = from_nodeid;
1066 kref_init(&r->res_ref);
1067 r->res_toss_time = jiffies;
1068
1069 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1070 if (error) {
1071 /* should never happen */
1072 dlm_free_rsb(r);
1073 spin_unlock(&ls->ls_rsbtbl[b].lock);
1074 goto retry;
1075 }
1076
1077 if (result)
1078 *result = DLM_LU_ADD;
1079 *r_nodeid = from_nodeid;
1080 error = 0;
1081 out_unlock:
1082 spin_unlock(&ls->ls_rsbtbl[b].lock);
1083 return error;
1084}
1085
1086static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1087{
1088 struct rb_node *n;
1089 struct dlm_rsb *r;
1090 int i;
1091
1092 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1093 spin_lock(&ls->ls_rsbtbl[i].lock);
1094 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1095 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1096 if (r->res_hash == hash)
1097 dlm_dump_rsb(r);
1098 }
1099 spin_unlock(&ls->ls_rsbtbl[i].lock);
1100 }
1101}
1102
1103void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len)
1104{
1105 struct dlm_rsb *r = NULL;
1106 uint32_t hash, b;
1107 int error;
1108
1109 hash = jhash(name, len, 0);
1110 b = hash & (ls->ls_rsbtbl_size - 1);
1111
1112 spin_lock(&ls->ls_rsbtbl[b].lock);
1113 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1114 if (!error)
1115 goto out_dump;
1116
1117 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1118 if (error)
1119 goto out;
1120 out_dump:
1121 dlm_dump_rsb(r);
1122 out:
1123 spin_unlock(&ls->ls_rsbtbl[b].lock);
1124}
1125
1126static void toss_rsb(struct kref *kref)
1127{
1128 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1129 struct dlm_ls *ls = r->res_ls;
1130
1131 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1132 kref_init(&r->res_ref);
1133 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1134 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
1135 r->res_toss_time = jiffies;
1136 ls->ls_rsbtbl[r->res_bucket].flags |= DLM_RTF_SHRINK;
1137 if (r->res_lvbptr) {
1138 dlm_free_lvb(r->res_lvbptr);
1139 r->res_lvbptr = NULL;
1140 }
1141}
1142
1143/* See comment for unhold_lkb */
1144
1145static void unhold_rsb(struct dlm_rsb *r)
1146{
1147 int rv;
1148 rv = kref_put(&r->res_ref, toss_rsb);
1149 DLM_ASSERT(!rv, dlm_dump_rsb(r););
1150}
1151
1152static void kill_rsb(struct kref *kref)
1153{
1154 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1155
1156 /* All work is done after the return from kref_put() so we
1157 can release the write_lock before the remove and free. */
1158
1159 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1160 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1161 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1162 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1163 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1164 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
1165}
1166
1167/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1168 The rsb must exist as long as any lkb's for it do. */
1169
1170static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1171{
1172 hold_rsb(r);
1173 lkb->lkb_resource = r;
1174}
1175
1176static void detach_lkb(struct dlm_lkb *lkb)
1177{
1178 if (lkb->lkb_resource) {
1179 put_rsb(lkb->lkb_resource);
1180 lkb->lkb_resource = NULL;
1181 }
1182}
1183
1184static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1185{
1186 struct dlm_lkb *lkb;
1187 int rv;
1188
1189 lkb = dlm_allocate_lkb(ls);
1190 if (!lkb)
1191 return -ENOMEM;
1192
1193 lkb->lkb_nodeid = -1;
1194 lkb->lkb_grmode = DLM_LOCK_IV;
1195 kref_init(&lkb->lkb_ref);
1196 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
1197 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
1198 INIT_LIST_HEAD(&lkb->lkb_time_list);
1199 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1200 mutex_init(&lkb->lkb_cb_mutex);
1201 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
1202
1203 idr_preload(GFP_NOFS);
1204 spin_lock(&ls->ls_lkbidr_spin);
1205 rv = idr_alloc(&ls->ls_lkbidr, lkb, 1, 0, GFP_NOWAIT);
1206 if (rv >= 0)
1207 lkb->lkb_id = rv;
1208 spin_unlock(&ls->ls_lkbidr_spin);
1209 idr_preload_end();
1210
1211 if (rv < 0) {
1212 log_error(ls, "create_lkb idr error %d", rv);
1213 return rv;
1214 }
1215
1216 *lkb_ret = lkb;
1217 return 0;
1218}
1219
1220static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1221{
1222 struct dlm_lkb *lkb;
1223
1224 spin_lock(&ls->ls_lkbidr_spin);
1225 lkb = idr_find(&ls->ls_lkbidr, lkid);
1226 if (lkb)
1227 kref_get(&lkb->lkb_ref);
1228 spin_unlock(&ls->ls_lkbidr_spin);
1229
1230 *lkb_ret = lkb;
1231 return lkb ? 0 : -ENOENT;
1232}
1233
1234static void kill_lkb(struct kref *kref)
1235{
1236 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1237
1238 /* All work is done after the return from kref_put() so we
1239 can release the write_lock before the detach_lkb */
1240
1241 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1242}
1243
1244/* __put_lkb() is used when an lkb may not have an rsb attached to
1245 it so we need to provide the lockspace explicitly */
1246
1247static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
1248{
1249 uint32_t lkid = lkb->lkb_id;
1250
1251 spin_lock(&ls->ls_lkbidr_spin);
1252 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
1253 idr_remove(&ls->ls_lkbidr, lkid);
1254 spin_unlock(&ls->ls_lkbidr_spin);
1255
1256 detach_lkb(lkb);
1257
1258 /* for local/process lkbs, lvbptr points to caller's lksb */
1259 if (lkb->lkb_lvbptr && is_master_copy(lkb))
1260 dlm_free_lvb(lkb->lkb_lvbptr);
1261 dlm_free_lkb(lkb);
1262 return 1;
1263 } else {
1264 spin_unlock(&ls->ls_lkbidr_spin);
1265 return 0;
1266 }
1267}
1268
1269int dlm_put_lkb(struct dlm_lkb *lkb)
1270{
1271 struct dlm_ls *ls;
1272
1273 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1274 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1275
1276 ls = lkb->lkb_resource->res_ls;
1277 return __put_lkb(ls, lkb);
1278}
1279
1280/* This is only called to add a reference when the code already holds
1281 a valid reference to the lkb, so there's no need for locking. */
1282
1283static inline void hold_lkb(struct dlm_lkb *lkb)
1284{
1285 kref_get(&lkb->lkb_ref);
1286}
1287
1288/* This is called when we need to remove a reference and are certain
1289 it's not the last ref. e.g. del_lkb is always called between a
1290 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1291 put_lkb would work fine, but would involve unnecessary locking */
1292
1293static inline void unhold_lkb(struct dlm_lkb *lkb)
1294{
1295 int rv;
1296 rv = kref_put(&lkb->lkb_ref, kill_lkb);
1297 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
1298}
1299
1300static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1301 int mode)
1302{
1303 struct dlm_lkb *lkb = NULL;
1304
1305 list_for_each_entry(lkb, head, lkb_statequeue)
1306 if (lkb->lkb_rqmode < mode)
1307 break;
1308
1309 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
1310}
1311
1312/* add/remove lkb to rsb's grant/convert/wait queue */
1313
1314static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1315{
1316 kref_get(&lkb->lkb_ref);
1317
1318 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1319
1320 lkb->lkb_timestamp = ktime_get();
1321
1322 lkb->lkb_status = status;
1323
1324 switch (status) {
1325 case DLM_LKSTS_WAITING:
1326 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1327 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1328 else
1329 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1330 break;
1331 case DLM_LKSTS_GRANTED:
1332 /* convention says granted locks kept in order of grmode */
1333 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1334 lkb->lkb_grmode);
1335 break;
1336 case DLM_LKSTS_CONVERT:
1337 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1338 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1339 else
1340 list_add_tail(&lkb->lkb_statequeue,
1341 &r->res_convertqueue);
1342 break;
1343 default:
1344 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1345 }
1346}
1347
1348static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1349{
1350 lkb->lkb_status = 0;
1351 list_del(&lkb->lkb_statequeue);
1352 unhold_lkb(lkb);
1353}
1354
1355static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1356{
1357 hold_lkb(lkb);
1358 del_lkb(r, lkb);
1359 add_lkb(r, lkb, sts);
1360 unhold_lkb(lkb);
1361}
1362
1363static int msg_reply_type(int mstype)
1364{
1365 switch (mstype) {
1366 case DLM_MSG_REQUEST:
1367 return DLM_MSG_REQUEST_REPLY;
1368 case DLM_MSG_CONVERT:
1369 return DLM_MSG_CONVERT_REPLY;
1370 case DLM_MSG_UNLOCK:
1371 return DLM_MSG_UNLOCK_REPLY;
1372 case DLM_MSG_CANCEL:
1373 return DLM_MSG_CANCEL_REPLY;
1374 case DLM_MSG_LOOKUP:
1375 return DLM_MSG_LOOKUP_REPLY;
1376 }
1377 return -1;
1378}
1379
1380static int nodeid_warned(int nodeid, int num_nodes, int *warned)
1381{
1382 int i;
1383
1384 for (i = 0; i < num_nodes; i++) {
1385 if (!warned[i]) {
1386 warned[i] = nodeid;
1387 return 0;
1388 }
1389 if (warned[i] == nodeid)
1390 return 1;
1391 }
1392 return 0;
1393}
1394
1395void dlm_scan_waiters(struct dlm_ls *ls)
1396{
1397 struct dlm_lkb *lkb;
1398 ktime_t zero = ktime_set(0, 0);
1399 s64 us;
1400 s64 debug_maxus = 0;
1401 u32 debug_scanned = 0;
1402 u32 debug_expired = 0;
1403 int num_nodes = 0;
1404 int *warned = NULL;
1405
1406 if (!dlm_config.ci_waitwarn_us)
1407 return;
1408
1409 mutex_lock(&ls->ls_waiters_mutex);
1410
1411 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1412 if (ktime_equal(lkb->lkb_wait_time, zero))
1413 continue;
1414
1415 debug_scanned++;
1416
1417 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
1418
1419 if (us < dlm_config.ci_waitwarn_us)
1420 continue;
1421
1422 lkb->lkb_wait_time = zero;
1423
1424 debug_expired++;
1425 if (us > debug_maxus)
1426 debug_maxus = us;
1427
1428 if (!num_nodes) {
1429 num_nodes = ls->ls_num_nodes;
1430 warned = kzalloc(num_nodes * sizeof(int), GFP_KERNEL);
1431 }
1432 if (!warned)
1433 continue;
1434 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
1435 continue;
1436
1437 log_error(ls, "waitwarn %x %lld %d us check connection to "
1438 "node %d", lkb->lkb_id, (long long)us,
1439 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
1440 }
1441 mutex_unlock(&ls->ls_waiters_mutex);
1442 kfree(warned);
1443
1444 if (debug_expired)
1445 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
1446 debug_scanned, debug_expired,
1447 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
1448}
1449
1450/* add/remove lkb from global waiters list of lkb's waiting for
1451 a reply from a remote node */
1452
1453static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
1454{
1455 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1456 int error = 0;
1457
1458 mutex_lock(&ls->ls_waiters_mutex);
1459
1460 if (is_overlap_unlock(lkb) ||
1461 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1462 error = -EINVAL;
1463 goto out;
1464 }
1465
1466 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1467 switch (mstype) {
1468 case DLM_MSG_UNLOCK:
1469 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
1470 break;
1471 case DLM_MSG_CANCEL:
1472 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
1473 break;
1474 default:
1475 error = -EBUSY;
1476 goto out;
1477 }
1478 lkb->lkb_wait_count++;
1479 hold_lkb(lkb);
1480
1481 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
1482 lkb->lkb_id, lkb->lkb_wait_type, mstype,
1483 lkb->lkb_wait_count, lkb->lkb_flags);
1484 goto out;
1485 }
1486
1487 DLM_ASSERT(!lkb->lkb_wait_count,
1488 dlm_print_lkb(lkb);
1489 printk("wait_count %d\n", lkb->lkb_wait_count););
1490
1491 lkb->lkb_wait_count++;
1492 lkb->lkb_wait_type = mstype;
1493 lkb->lkb_wait_time = ktime_get();
1494 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
1495 hold_lkb(lkb);
1496 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1497 out:
1498 if (error)
1499 log_error(ls, "addwait error %x %d flags %x %d %d %s",
1500 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1501 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
1502 mutex_unlock(&ls->ls_waiters_mutex);
1503 return error;
1504}
1505
1506/* We clear the RESEND flag because we might be taking an lkb off the waiters
1507 list as part of process_requestqueue (e.g. a lookup that has an optimized
1508 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1509 set RESEND and dlm_recover_waiters_post() */
1510
1511static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1512 struct dlm_message *ms)
1513{
1514 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1515 int overlap_done = 0;
1516
1517 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
1518 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
1519 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1520 overlap_done = 1;
1521 goto out_del;
1522 }
1523
1524 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
1525 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
1526 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1527 overlap_done = 1;
1528 goto out_del;
1529 }
1530
1531 /* Cancel state was preemptively cleared by a successful convert,
1532 see next comment, nothing to do. */
1533
1534 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1535 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1536 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1537 lkb->lkb_id, lkb->lkb_wait_type);
1538 return -1;
1539 }
1540
1541 /* Remove for the convert reply, and premptively remove for the
1542 cancel reply. A convert has been granted while there's still
1543 an outstanding cancel on it (the cancel is moot and the result
1544 in the cancel reply should be 0). We preempt the cancel reply
1545 because the app gets the convert result and then can follow up
1546 with another op, like convert. This subsequent op would see the
1547 lingering state of the cancel and fail with -EBUSY. */
1548
1549 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1550 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1551 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1552 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1553 lkb->lkb_id);
1554 lkb->lkb_wait_type = 0;
1555 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1556 lkb->lkb_wait_count--;
1557 goto out_del;
1558 }
1559
1560 /* N.B. type of reply may not always correspond to type of original
1561 msg due to lookup->request optimization, verify others? */
1562
1563 if (lkb->lkb_wait_type) {
1564 lkb->lkb_wait_type = 0;
1565 goto out_del;
1566 }
1567
1568 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1569 lkb->lkb_id, ms ? ms->m_header.h_nodeid : 0, lkb->lkb_remid,
1570 mstype, lkb->lkb_flags);
1571 return -1;
1572
1573 out_del:
1574 /* the force-unlock/cancel has completed and we haven't recvd a reply
1575 to the op that was in progress prior to the unlock/cancel; we
1576 give up on any reply to the earlier op. FIXME: not sure when/how
1577 this would happen */
1578
1579 if (overlap_done && lkb->lkb_wait_type) {
1580 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
1581 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1582 lkb->lkb_wait_count--;
1583 lkb->lkb_wait_type = 0;
1584 }
1585
1586 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1587
1588 lkb->lkb_flags &= ~DLM_IFL_RESEND;
1589 lkb->lkb_wait_count--;
1590 if (!lkb->lkb_wait_count)
1591 list_del_init(&lkb->lkb_wait_reply);
1592 unhold_lkb(lkb);
1593 return 0;
1594}
1595
1596static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
1597{
1598 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1599 int error;
1600
1601 mutex_lock(&ls->ls_waiters_mutex);
1602 error = _remove_from_waiters(lkb, mstype, NULL);
1603 mutex_unlock(&ls->ls_waiters_mutex);
1604 return error;
1605}
1606
1607/* Handles situations where we might be processing a "fake" or "stub" reply in
1608 which we can't try to take waiters_mutex again. */
1609
1610static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1611{
1612 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1613 int error;
1614
1615 if (ms->m_flags != DLM_IFL_STUB_MS)
1616 mutex_lock(&ls->ls_waiters_mutex);
1617 error = _remove_from_waiters(lkb, ms->m_type, ms);
1618 if (ms->m_flags != DLM_IFL_STUB_MS)
1619 mutex_unlock(&ls->ls_waiters_mutex);
1620 return error;
1621}
1622
1623/* If there's an rsb for the same resource being removed, ensure
1624 that the remove message is sent before the new lookup message.
1625 It should be rare to need a delay here, but if not, then it may
1626 be worthwhile to add a proper wait mechanism rather than a delay. */
1627
1628static void wait_pending_remove(struct dlm_rsb *r)
1629{
1630 struct dlm_ls *ls = r->res_ls;
1631 restart:
1632 spin_lock(&ls->ls_remove_spin);
1633 if (ls->ls_remove_len &&
1634 !rsb_cmp(r, ls->ls_remove_name, ls->ls_remove_len)) {
1635 log_debug(ls, "delay lookup for remove dir %d %s",
1636 r->res_dir_nodeid, r->res_name);
1637 spin_unlock(&ls->ls_remove_spin);
1638 msleep(1);
1639 goto restart;
1640 }
1641 spin_unlock(&ls->ls_remove_spin);
1642}
1643
1644/*
1645 * ls_remove_spin protects ls_remove_name and ls_remove_len which are
1646 * read by other threads in wait_pending_remove. ls_remove_names
1647 * and ls_remove_lens are only used by the scan thread, so they do
1648 * not need protection.
1649 */
1650
1651static void shrink_bucket(struct dlm_ls *ls, int b)
1652{
1653 struct rb_node *n, *next;
1654 struct dlm_rsb *r;
1655 char *name;
1656 int our_nodeid = dlm_our_nodeid();
1657 int remote_count = 0;
1658 int need_shrink = 0;
1659 int i, len, rv;
1660
1661 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
1662
1663 spin_lock(&ls->ls_rsbtbl[b].lock);
1664
1665 if (!(ls->ls_rsbtbl[b].flags & DLM_RTF_SHRINK)) {
1666 spin_unlock(&ls->ls_rsbtbl[b].lock);
1667 return;
1668 }
1669
1670 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) {
1671 next = rb_next(n);
1672 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1673
1674 /* If we're the directory record for this rsb, and
1675 we're not the master of it, then we need to wait
1676 for the master node to send us a dir remove for
1677 before removing the dir record. */
1678
1679 if (!dlm_no_directory(ls) &&
1680 (r->res_master_nodeid != our_nodeid) &&
1681 (dlm_dir_nodeid(r) == our_nodeid)) {
1682 continue;
1683 }
1684
1685 need_shrink = 1;
1686
1687 if (!time_after_eq(jiffies, r->res_toss_time +
1688 dlm_config.ci_toss_secs * HZ)) {
1689 continue;
1690 }
1691
1692 if (!dlm_no_directory(ls) &&
1693 (r->res_master_nodeid == our_nodeid) &&
1694 (dlm_dir_nodeid(r) != our_nodeid)) {
1695
1696 /* We're the master of this rsb but we're not
1697 the directory record, so we need to tell the
1698 dir node to remove the dir record. */
1699
1700 ls->ls_remove_lens[remote_count] = r->res_length;
1701 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1702 DLM_RESNAME_MAXLEN);
1703 remote_count++;
1704
1705 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1706 break;
1707 continue;
1708 }
1709
1710 if (!kref_put(&r->res_ref, kill_rsb)) {
1711 log_error(ls, "tossed rsb in use %s", r->res_name);
1712 continue;
1713 }
1714
1715 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1716 dlm_free_rsb(r);
1717 }
1718
1719 if (need_shrink)
1720 ls->ls_rsbtbl[b].flags |= DLM_RTF_SHRINK;
1721 else
1722 ls->ls_rsbtbl[b].flags &= ~DLM_RTF_SHRINK;
1723 spin_unlock(&ls->ls_rsbtbl[b].lock);
1724
1725 /*
1726 * While searching for rsb's to free, we found some that require
1727 * remote removal. We leave them in place and find them again here
1728 * so there is a very small gap between removing them from the toss
1729 * list and sending the removal. Keeping this gap small is
1730 * important to keep us (the master node) from being out of sync
1731 * with the remote dir node for very long.
1732 *
1733 * From the time the rsb is removed from toss until just after
1734 * send_remove, the rsb name is saved in ls_remove_name. A new
1735 * lookup checks this to ensure that a new lookup message for the
1736 * same resource name is not sent just before the remove message.
1737 */
1738
1739 for (i = 0; i < remote_count; i++) {
1740 name = ls->ls_remove_names[i];
1741 len = ls->ls_remove_lens[i];
1742
1743 spin_lock(&ls->ls_rsbtbl[b].lock);
1744 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1745 if (rv) {
1746 spin_unlock(&ls->ls_rsbtbl[b].lock);
1747 log_debug(ls, "remove_name not toss %s", name);
1748 continue;
1749 }
1750
1751 if (r->res_master_nodeid != our_nodeid) {
1752 spin_unlock(&ls->ls_rsbtbl[b].lock);
1753 log_debug(ls, "remove_name master %d dir %d our %d %s",
1754 r->res_master_nodeid, r->res_dir_nodeid,
1755 our_nodeid, name);
1756 continue;
1757 }
1758
1759 if (r->res_dir_nodeid == our_nodeid) {
1760 /* should never happen */
1761 spin_unlock(&ls->ls_rsbtbl[b].lock);
1762 log_error(ls, "remove_name dir %d master %d our %d %s",
1763 r->res_dir_nodeid, r->res_master_nodeid,
1764 our_nodeid, name);
1765 continue;
1766 }
1767
1768 if (!time_after_eq(jiffies, r->res_toss_time +
1769 dlm_config.ci_toss_secs * HZ)) {
1770 spin_unlock(&ls->ls_rsbtbl[b].lock);
1771 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1772 r->res_toss_time, jiffies, name);
1773 continue;
1774 }
1775
1776 if (!kref_put(&r->res_ref, kill_rsb)) {
1777 spin_unlock(&ls->ls_rsbtbl[b].lock);
1778 log_error(ls, "remove_name in use %s", name);
1779 continue;
1780 }
1781
1782 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1783
1784 /* block lookup of same name until we've sent remove */
1785 spin_lock(&ls->ls_remove_spin);
1786 ls->ls_remove_len = len;
1787 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
1788 spin_unlock(&ls->ls_remove_spin);
1789 spin_unlock(&ls->ls_rsbtbl[b].lock);
1790
1791 send_remove(r);
1792
1793 /* allow lookup of name again */
1794 spin_lock(&ls->ls_remove_spin);
1795 ls->ls_remove_len = 0;
1796 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
1797 spin_unlock(&ls->ls_remove_spin);
1798
1799 dlm_free_rsb(r);
1800 }
1801}
1802
1803void dlm_scan_rsbs(struct dlm_ls *ls)
1804{
1805 int i;
1806
1807 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1808 shrink_bucket(ls, i);
1809 if (dlm_locking_stopped(ls))
1810 break;
1811 cond_resched();
1812 }
1813}
1814
1815static void add_timeout(struct dlm_lkb *lkb)
1816{
1817 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1818
1819 if (is_master_copy(lkb))
1820 return;
1821
1822 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1823 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1824 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1825 goto add_it;
1826 }
1827 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1828 goto add_it;
1829 return;
1830
1831 add_it:
1832 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1833 mutex_lock(&ls->ls_timeout_mutex);
1834 hold_lkb(lkb);
1835 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1836 mutex_unlock(&ls->ls_timeout_mutex);
1837}
1838
1839static void del_timeout(struct dlm_lkb *lkb)
1840{
1841 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1842
1843 mutex_lock(&ls->ls_timeout_mutex);
1844 if (!list_empty(&lkb->lkb_time_list)) {
1845 list_del_init(&lkb->lkb_time_list);
1846 unhold_lkb(lkb);
1847 }
1848 mutex_unlock(&ls->ls_timeout_mutex);
1849}
1850
1851/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1852 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1853 and then lock rsb because of lock ordering in add_timeout. We may need
1854 to specify some special timeout-related bits in the lkb that are just to
1855 be accessed under the timeout_mutex. */
1856
1857void dlm_scan_timeout(struct dlm_ls *ls)
1858{
1859 struct dlm_rsb *r;
1860 struct dlm_lkb *lkb;
1861 int do_cancel, do_warn;
1862 s64 wait_us;
1863
1864 for (;;) {
1865 if (dlm_locking_stopped(ls))
1866 break;
1867
1868 do_cancel = 0;
1869 do_warn = 0;
1870 mutex_lock(&ls->ls_timeout_mutex);
1871 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1872
1873 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1874 lkb->lkb_timestamp));
1875
1876 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
1877 wait_us >= (lkb->lkb_timeout_cs * 10000))
1878 do_cancel = 1;
1879
1880 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
1881 wait_us >= dlm_config.ci_timewarn_cs * 10000)
1882 do_warn = 1;
1883
1884 if (!do_cancel && !do_warn)
1885 continue;
1886 hold_lkb(lkb);
1887 break;
1888 }
1889 mutex_unlock(&ls->ls_timeout_mutex);
1890
1891 if (!do_cancel && !do_warn)
1892 break;
1893
1894 r = lkb->lkb_resource;
1895 hold_rsb(r);
1896 lock_rsb(r);
1897
1898 if (do_warn) {
1899 /* clear flag so we only warn once */
1900 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1901 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1902 del_timeout(lkb);
1903 dlm_timeout_warn(lkb);
1904 }
1905
1906 if (do_cancel) {
1907 log_debug(ls, "timeout cancel %x node %d %s",
1908 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1909 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1910 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1911 del_timeout(lkb);
1912 _cancel_lock(r, lkb);
1913 }
1914
1915 unlock_rsb(r);
1916 unhold_rsb(r);
1917 dlm_put_lkb(lkb);
1918 }
1919}
1920
1921/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1922 dlm_recoverd before checking/setting ls_recover_begin. */
1923
1924void dlm_adjust_timeouts(struct dlm_ls *ls)
1925{
1926 struct dlm_lkb *lkb;
1927 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
1928
1929 ls->ls_recover_begin = 0;
1930 mutex_lock(&ls->ls_timeout_mutex);
1931 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
1932 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
1933 mutex_unlock(&ls->ls_timeout_mutex);
1934
1935 if (!dlm_config.ci_waitwarn_us)
1936 return;
1937
1938 mutex_lock(&ls->ls_waiters_mutex);
1939 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1940 if (ktime_to_us(lkb->lkb_wait_time))
1941 lkb->lkb_wait_time = ktime_get();
1942 }
1943 mutex_unlock(&ls->ls_waiters_mutex);
1944}
1945
1946/* lkb is master or local copy */
1947
1948static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1949{
1950 int b, len = r->res_ls->ls_lvblen;
1951
1952 /* b=1 lvb returned to caller
1953 b=0 lvb written to rsb or invalidated
1954 b=-1 do nothing */
1955
1956 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1957
1958 if (b == 1) {
1959 if (!lkb->lkb_lvbptr)
1960 return;
1961
1962 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1963 return;
1964
1965 if (!r->res_lvbptr)
1966 return;
1967
1968 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1969 lkb->lkb_lvbseq = r->res_lvbseq;
1970
1971 } else if (b == 0) {
1972 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1973 rsb_set_flag(r, RSB_VALNOTVALID);
1974 return;
1975 }
1976
1977 if (!lkb->lkb_lvbptr)
1978 return;
1979
1980 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1981 return;
1982
1983 if (!r->res_lvbptr)
1984 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1985
1986 if (!r->res_lvbptr)
1987 return;
1988
1989 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1990 r->res_lvbseq++;
1991 lkb->lkb_lvbseq = r->res_lvbseq;
1992 rsb_clear_flag(r, RSB_VALNOTVALID);
1993 }
1994
1995 if (rsb_flag(r, RSB_VALNOTVALID))
1996 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1997}
1998
1999static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2000{
2001 if (lkb->lkb_grmode < DLM_LOCK_PW)
2002 return;
2003
2004 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
2005 rsb_set_flag(r, RSB_VALNOTVALID);
2006 return;
2007 }
2008
2009 if (!lkb->lkb_lvbptr)
2010 return;
2011
2012 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2013 return;
2014
2015 if (!r->res_lvbptr)
2016 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
2017
2018 if (!r->res_lvbptr)
2019 return;
2020
2021 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2022 r->res_lvbseq++;
2023 rsb_clear_flag(r, RSB_VALNOTVALID);
2024}
2025
2026/* lkb is process copy (pc) */
2027
2028static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2029 struct dlm_message *ms)
2030{
2031 int b;
2032
2033 if (!lkb->lkb_lvbptr)
2034 return;
2035
2036 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2037 return;
2038
2039 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
2040 if (b == 1) {
2041 int len = receive_extralen(ms);
2042 if (len > r->res_ls->ls_lvblen)
2043 len = r->res_ls->ls_lvblen;
2044 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
2045 lkb->lkb_lvbseq = ms->m_lvbseq;
2046 }
2047}
2048
2049/* Manipulate lkb's on rsb's convert/granted/waiting queues
2050 remove_lock -- used for unlock, removes lkb from granted
2051 revert_lock -- used for cancel, moves lkb from convert to granted
2052 grant_lock -- used for request and convert, adds lkb to granted or
2053 moves lkb from convert or waiting to granted
2054
2055 Each of these is used for master or local copy lkb's. There is
2056 also a _pc() variation used to make the corresponding change on
2057 a process copy (pc) lkb. */
2058
2059static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2060{
2061 del_lkb(r, lkb);
2062 lkb->lkb_grmode = DLM_LOCK_IV;
2063 /* this unhold undoes the original ref from create_lkb()
2064 so this leads to the lkb being freed */
2065 unhold_lkb(lkb);
2066}
2067
2068static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2069{
2070 set_lvb_unlock(r, lkb);
2071 _remove_lock(r, lkb);
2072}
2073
2074static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2075{
2076 _remove_lock(r, lkb);
2077}
2078
2079/* returns: 0 did nothing
2080 1 moved lock to granted
2081 -1 removed lock */
2082
2083static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2084{
2085 int rv = 0;
2086
2087 lkb->lkb_rqmode = DLM_LOCK_IV;
2088
2089 switch (lkb->lkb_status) {
2090 case DLM_LKSTS_GRANTED:
2091 break;
2092 case DLM_LKSTS_CONVERT:
2093 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2094 rv = 1;
2095 break;
2096 case DLM_LKSTS_WAITING:
2097 del_lkb(r, lkb);
2098 lkb->lkb_grmode = DLM_LOCK_IV;
2099 /* this unhold undoes the original ref from create_lkb()
2100 so this leads to the lkb being freed */
2101 unhold_lkb(lkb);
2102 rv = -1;
2103 break;
2104 default:
2105 log_print("invalid status for revert %d", lkb->lkb_status);
2106 }
2107 return rv;
2108}
2109
2110static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2111{
2112 return revert_lock(r, lkb);
2113}
2114
2115static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2116{
2117 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
2118 lkb->lkb_grmode = lkb->lkb_rqmode;
2119 if (lkb->lkb_status)
2120 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2121 else
2122 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
2123 }
2124
2125 lkb->lkb_rqmode = DLM_LOCK_IV;
2126 lkb->lkb_highbast = 0;
2127}
2128
2129static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2130{
2131 set_lvb_lock(r, lkb);
2132 _grant_lock(r, lkb);
2133}
2134
2135static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2136 struct dlm_message *ms)
2137{
2138 set_lvb_lock_pc(r, lkb, ms);
2139 _grant_lock(r, lkb);
2140}
2141
2142/* called by grant_pending_locks() which means an async grant message must
2143 be sent to the requesting node in addition to granting the lock if the
2144 lkb belongs to a remote node. */
2145
2146static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
2147{
2148 grant_lock(r, lkb);
2149 if (is_master_copy(lkb))
2150 send_grant(r, lkb);
2151 else
2152 queue_cast(r, lkb, 0);
2153}
2154
2155/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
2156 change the granted/requested modes. We're munging things accordingly in
2157 the process copy.
2158 CONVDEADLK: our grmode may have been forced down to NL to resolve a
2159 conversion deadlock
2160 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
2161 compatible with other granted locks */
2162
2163static void munge_demoted(struct dlm_lkb *lkb)
2164{
2165 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
2166 log_print("munge_demoted %x invalid modes gr %d rq %d",
2167 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
2168 return;
2169 }
2170
2171 lkb->lkb_grmode = DLM_LOCK_NL;
2172}
2173
2174static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
2175{
2176 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
2177 ms->m_type != DLM_MSG_GRANT) {
2178 log_print("munge_altmode %x invalid reply type %d",
2179 lkb->lkb_id, ms->m_type);
2180 return;
2181 }
2182
2183 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
2184 lkb->lkb_rqmode = DLM_LOCK_PR;
2185 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
2186 lkb->lkb_rqmode = DLM_LOCK_CW;
2187 else {
2188 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
2189 dlm_print_lkb(lkb);
2190 }
2191}
2192
2193static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
2194{
2195 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
2196 lkb_statequeue);
2197 if (lkb->lkb_id == first->lkb_id)
2198 return 1;
2199
2200 return 0;
2201}
2202
2203/* Check if the given lkb conflicts with another lkb on the queue. */
2204
2205static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
2206{
2207 struct dlm_lkb *this;
2208
2209 list_for_each_entry(this, head, lkb_statequeue) {
2210 if (this == lkb)
2211 continue;
2212 if (!modes_compat(this, lkb))
2213 return 1;
2214 }
2215 return 0;
2216}
2217
2218/*
2219 * "A conversion deadlock arises with a pair of lock requests in the converting
2220 * queue for one resource. The granted mode of each lock blocks the requested
2221 * mode of the other lock."
2222 *
2223 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
2224 * convert queue from being granted, then deadlk/demote lkb.
2225 *
2226 * Example:
2227 * Granted Queue: empty
2228 * Convert Queue: NL->EX (first lock)
2229 * PR->EX (second lock)
2230 *
2231 * The first lock can't be granted because of the granted mode of the second
2232 * lock and the second lock can't be granted because it's not first in the
2233 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2234 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2235 * flag set and return DEMOTED in the lksb flags.
2236 *
2237 * Originally, this function detected conv-deadlk in a more limited scope:
2238 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2239 * - if lkb1 was the first entry in the queue (not just earlier), and was
2240 * blocked by the granted mode of lkb2, and there was nothing on the
2241 * granted queue preventing lkb1 from being granted immediately, i.e.
2242 * lkb2 was the only thing preventing lkb1 from being granted.
2243 *
2244 * That second condition meant we'd only say there was conv-deadlk if
2245 * resolving it (by demotion) would lead to the first lock on the convert
2246 * queue being granted right away. It allowed conversion deadlocks to exist
2247 * between locks on the convert queue while they couldn't be granted anyway.
2248 *
2249 * Now, we detect and take action on conversion deadlocks immediately when
2250 * they're created, even if they may not be immediately consequential. If
2251 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2252 * mode that would prevent lkb1's conversion from being granted, we do a
2253 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2254 * I think this means that the lkb_is_ahead condition below should always
2255 * be zero, i.e. there will never be conv-deadlk between two locks that are
2256 * both already on the convert queue.
2257 */
2258
2259static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
2260{
2261 struct dlm_lkb *lkb1;
2262 int lkb_is_ahead = 0;
2263
2264 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2265 if (lkb1 == lkb2) {
2266 lkb_is_ahead = 1;
2267 continue;
2268 }
2269
2270 if (!lkb_is_ahead) {
2271 if (!modes_compat(lkb2, lkb1))
2272 return 1;
2273 } else {
2274 if (!modes_compat(lkb2, lkb1) &&
2275 !modes_compat(lkb1, lkb2))
2276 return 1;
2277 }
2278 }
2279 return 0;
2280}
2281
2282/*
2283 * Return 1 if the lock can be granted, 0 otherwise.
2284 * Also detect and resolve conversion deadlocks.
2285 *
2286 * lkb is the lock to be granted
2287 *
2288 * now is 1 if the function is being called in the context of the
2289 * immediate request, it is 0 if called later, after the lock has been
2290 * queued.
2291 *
2292 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2293 * after recovery.
2294 *
2295 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2296 */
2297
2298static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2299 int recover)
2300{
2301 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2302
2303 /*
2304 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2305 * a new request for a NL mode lock being blocked.
2306 *
2307 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2308 * request, then it would be granted. In essence, the use of this flag
2309 * tells the Lock Manager to expedite theis request by not considering
2310 * what may be in the CONVERTING or WAITING queues... As of this
2311 * writing, the EXPEDITE flag can be used only with new requests for NL
2312 * mode locks. This flag is not valid for conversion requests.
2313 *
2314 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2315 * conversion or used with a non-NL requested mode. We also know an
2316 * EXPEDITE request is always granted immediately, so now must always
2317 * be 1. The full condition to grant an expedite request: (now &&
2318 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2319 * therefore be shortened to just checking the flag.
2320 */
2321
2322 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
2323 return 1;
2324
2325 /*
2326 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2327 * added to the remaining conditions.
2328 */
2329
2330 if (queue_conflict(&r->res_grantqueue, lkb))
2331 return 0;
2332
2333 /*
2334 * 6-3: By default, a conversion request is immediately granted if the
2335 * requested mode is compatible with the modes of all other granted
2336 * locks
2337 */
2338
2339 if (queue_conflict(&r->res_convertqueue, lkb))
2340 return 0;
2341
2342 /*
2343 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2344 * locks for a recovered rsb, on which lkb's have been rebuilt.
2345 * The lkb's may have been rebuilt on the queues in a different
2346 * order than they were in on the previous master. So, granting
2347 * queued conversions in order after recovery doesn't make sense
2348 * since the order hasn't been preserved anyway. The new order
2349 * could also have created a new "in place" conversion deadlock.
2350 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2351 * After recovery, there would be no granted locks, and possibly
2352 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2353 * recovery, grant conversions without considering order.
2354 */
2355
2356 if (conv && recover)
2357 return 1;
2358
2359 /*
2360 * 6-5: But the default algorithm for deciding whether to grant or
2361 * queue conversion requests does not by itself guarantee that such
2362 * requests are serviced on a "first come first serve" basis. This, in
2363 * turn, can lead to a phenomenon known as "indefinate postponement".
2364 *
2365 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2366 * the system service employed to request a lock conversion. This flag
2367 * forces certain conversion requests to be queued, even if they are
2368 * compatible with the granted modes of other locks on the same
2369 * resource. Thus, the use of this flag results in conversion requests
2370 * being ordered on a "first come first servce" basis.
2371 *
2372 * DCT: This condition is all about new conversions being able to occur
2373 * "in place" while the lock remains on the granted queue (assuming
2374 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2375 * doesn't _have_ to go onto the convert queue where it's processed in
2376 * order. The "now" variable is necessary to distinguish converts
2377 * being received and processed for the first time now, because once a
2378 * convert is moved to the conversion queue the condition below applies
2379 * requiring fifo granting.
2380 */
2381
2382 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
2383 return 1;
2384
2385 /*
2386 * Even if the convert is compat with all granted locks,
2387 * QUECVT forces it behind other locks on the convert queue.
2388 */
2389
2390 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2391 if (list_empty(&r->res_convertqueue))
2392 return 1;
2393 else
2394 return 0;
2395 }
2396
2397 /*
2398 * The NOORDER flag is set to avoid the standard vms rules on grant
2399 * order.
2400 */
2401
2402 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
2403 return 1;
2404
2405 /*
2406 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2407 * granted until all other conversion requests ahead of it are granted
2408 * and/or canceled.
2409 */
2410
2411 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
2412 return 1;
2413
2414 /*
2415 * 6-4: By default, a new request is immediately granted only if all
2416 * three of the following conditions are satisfied when the request is
2417 * issued:
2418 * - The queue of ungranted conversion requests for the resource is
2419 * empty.
2420 * - The queue of ungranted new requests for the resource is empty.
2421 * - The mode of the new request is compatible with the most
2422 * restrictive mode of all granted locks on the resource.
2423 */
2424
2425 if (now && !conv && list_empty(&r->res_convertqueue) &&
2426 list_empty(&r->res_waitqueue))
2427 return 1;
2428
2429 /*
2430 * 6-4: Once a lock request is in the queue of ungranted new requests,
2431 * it cannot be granted until the queue of ungranted conversion
2432 * requests is empty, all ungranted new requests ahead of it are
2433 * granted and/or canceled, and it is compatible with the granted mode
2434 * of the most restrictive lock granted on the resource.
2435 */
2436
2437 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2438 first_in_list(lkb, &r->res_waitqueue))
2439 return 1;
2440
2441 return 0;
2442}
2443
2444static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2445 int recover, int *err)
2446{
2447 int rv;
2448 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
2449 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2450
2451 if (err)
2452 *err = 0;
2453
2454 rv = _can_be_granted(r, lkb, now, recover);
2455 if (rv)
2456 goto out;
2457
2458 /*
2459 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2460 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2461 * cancels one of the locks.
2462 */
2463
2464 if (is_convert && can_be_queued(lkb) &&
2465 conversion_deadlock_detect(r, lkb)) {
2466 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2467 lkb->lkb_grmode = DLM_LOCK_NL;
2468 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
2469 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
2470 if (err)
2471 *err = -EDEADLK;
2472 else {
2473 log_print("can_be_granted deadlock %x now %d",
2474 lkb->lkb_id, now);
2475 dlm_dump_rsb(r);
2476 }
2477 }
2478 goto out;
2479 }
2480
2481 /*
2482 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2483 * to grant a request in a mode other than the normal rqmode. It's a
2484 * simple way to provide a big optimization to applications that can
2485 * use them.
2486 */
2487
2488 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
2489 alt = DLM_LOCK_PR;
2490 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
2491 alt = DLM_LOCK_CW;
2492
2493 if (alt) {
2494 lkb->lkb_rqmode = alt;
2495 rv = _can_be_granted(r, lkb, now, 0);
2496 if (rv)
2497 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
2498 else
2499 lkb->lkb_rqmode = rqmode;
2500 }
2501 out:
2502 return rv;
2503}
2504
2505/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
2506 for locks pending on the convert list. Once verified (watch for these
2507 log_prints), we should be able to just call _can_be_granted() and not
2508 bother with the demote/deadlk cases here (and there's no easy way to deal
2509 with a deadlk here, we'd have to generate something like grant_lock with
2510 the deadlk error.) */
2511
2512/* Returns the highest requested mode of all blocked conversions; sets
2513 cw if there's a blocked conversion to DLM_LOCK_CW. */
2514
2515static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2516 unsigned int *count)
2517{
2518 struct dlm_lkb *lkb, *s;
2519 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
2520 int hi, demoted, quit, grant_restart, demote_restart;
2521 int deadlk;
2522
2523 quit = 0;
2524 restart:
2525 grant_restart = 0;
2526 demote_restart = 0;
2527 hi = DLM_LOCK_IV;
2528
2529 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2530 demoted = is_demoted(lkb);
2531 deadlk = 0;
2532
2533 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
2534 grant_lock_pending(r, lkb);
2535 grant_restart = 1;
2536 if (count)
2537 (*count)++;
2538 continue;
2539 }
2540
2541 if (!demoted && is_demoted(lkb)) {
2542 log_print("WARN: pending demoted %x node %d %s",
2543 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2544 demote_restart = 1;
2545 continue;
2546 }
2547
2548 if (deadlk) {
2549 log_print("WARN: pending deadlock %x node %d %s",
2550 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2551 dlm_dump_rsb(r);
2552 continue;
2553 }
2554
2555 hi = max_t(int, lkb->lkb_rqmode, hi);
2556
2557 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2558 *cw = 1;
2559 }
2560
2561 if (grant_restart)
2562 goto restart;
2563 if (demote_restart && !quit) {
2564 quit = 1;
2565 goto restart;
2566 }
2567
2568 return max_t(int, high, hi);
2569}
2570
2571static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2572 unsigned int *count)
2573{
2574 struct dlm_lkb *lkb, *s;
2575
2576 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
2577 if (can_be_granted(r, lkb, 0, 0, NULL)) {
2578 grant_lock_pending(r, lkb);
2579 if (count)
2580 (*count)++;
2581 } else {
2582 high = max_t(int, lkb->lkb_rqmode, high);
2583 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2584 *cw = 1;
2585 }
2586 }
2587
2588 return high;
2589}
2590
2591/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2592 on either the convert or waiting queue.
2593 high is the largest rqmode of all locks blocked on the convert or
2594 waiting queue. */
2595
2596static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2597{
2598 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2599 if (gr->lkb_highbast < DLM_LOCK_EX)
2600 return 1;
2601 return 0;
2602 }
2603
2604 if (gr->lkb_highbast < high &&
2605 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2606 return 1;
2607 return 0;
2608}
2609
2610static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
2611{
2612 struct dlm_lkb *lkb, *s;
2613 int high = DLM_LOCK_IV;
2614 int cw = 0;
2615
2616 if (!is_master(r)) {
2617 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2618 dlm_dump_rsb(r);
2619 return;
2620 }
2621
2622 high = grant_pending_convert(r, high, &cw, count);
2623 high = grant_pending_wait(r, high, &cw, count);
2624
2625 if (high == DLM_LOCK_IV)
2626 return;
2627
2628 /*
2629 * If there are locks left on the wait/convert queue then send blocking
2630 * ASTs to granted locks based on the largest requested mode (high)
2631 * found above.
2632 */
2633
2634 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
2635 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
2636 if (cw && high == DLM_LOCK_PR &&
2637 lkb->lkb_grmode == DLM_LOCK_PR)
2638 queue_bast(r, lkb, DLM_LOCK_CW);
2639 else
2640 queue_bast(r, lkb, high);
2641 lkb->lkb_highbast = high;
2642 }
2643 }
2644}
2645
2646static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2647{
2648 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2649 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2650 if (gr->lkb_highbast < DLM_LOCK_EX)
2651 return 1;
2652 return 0;
2653 }
2654
2655 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2656 return 1;
2657 return 0;
2658}
2659
2660static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2661 struct dlm_lkb *lkb)
2662{
2663 struct dlm_lkb *gr;
2664
2665 list_for_each_entry(gr, head, lkb_statequeue) {
2666 /* skip self when sending basts to convertqueue */
2667 if (gr == lkb)
2668 continue;
2669 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
2670 queue_bast(r, gr, lkb->lkb_rqmode);
2671 gr->lkb_highbast = lkb->lkb_rqmode;
2672 }
2673 }
2674}
2675
2676static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2677{
2678 send_bast_queue(r, &r->res_grantqueue, lkb);
2679}
2680
2681static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2682{
2683 send_bast_queue(r, &r->res_grantqueue, lkb);
2684 send_bast_queue(r, &r->res_convertqueue, lkb);
2685}
2686
2687/* set_master(r, lkb) -- set the master nodeid of a resource
2688
2689 The purpose of this function is to set the nodeid field in the given
2690 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2691 known, it can just be copied to the lkb and the function will return
2692 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2693 before it can be copied to the lkb.
2694
2695 When the rsb nodeid is being looked up remotely, the initial lkb
2696 causing the lookup is kept on the ls_waiters list waiting for the
2697 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2698 on the rsb's res_lookup list until the master is verified.
2699
2700 Return values:
2701 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2702 1: the rsb master is not available and the lkb has been placed on
2703 a wait queue
2704*/
2705
2706static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2707{
2708 int our_nodeid = dlm_our_nodeid();
2709
2710 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2711 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2712 r->res_first_lkid = lkb->lkb_id;
2713 lkb->lkb_nodeid = r->res_nodeid;
2714 return 0;
2715 }
2716
2717 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2718 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2719 return 1;
2720 }
2721
2722 if (r->res_master_nodeid == our_nodeid) {
2723 lkb->lkb_nodeid = 0;
2724 return 0;
2725 }
2726
2727 if (r->res_master_nodeid) {
2728 lkb->lkb_nodeid = r->res_master_nodeid;
2729 return 0;
2730 }
2731
2732 if (dlm_dir_nodeid(r) == our_nodeid) {
2733 /* This is a somewhat unusual case; find_rsb will usually
2734 have set res_master_nodeid when dir nodeid is local, but
2735 there are cases where we become the dir node after we've
2736 past find_rsb and go through _request_lock again.
2737 confirm_master() or process_lookup_list() needs to be
2738 called after this. */
2739 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2740 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2741 r->res_name);
2742 r->res_master_nodeid = our_nodeid;
2743 r->res_nodeid = 0;
2744 lkb->lkb_nodeid = 0;
2745 return 0;
2746 }
2747
2748 wait_pending_remove(r);
2749
2750 r->res_first_lkid = lkb->lkb_id;
2751 send_lookup(r, lkb);
2752 return 1;
2753}
2754
2755static void process_lookup_list(struct dlm_rsb *r)
2756{
2757 struct dlm_lkb *lkb, *safe;
2758
2759 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
2760 list_del_init(&lkb->lkb_rsb_lookup);
2761 _request_lock(r, lkb);
2762 schedule();
2763 }
2764}
2765
2766/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2767
2768static void confirm_master(struct dlm_rsb *r, int error)
2769{
2770 struct dlm_lkb *lkb;
2771
2772 if (!r->res_first_lkid)
2773 return;
2774
2775 switch (error) {
2776 case 0:
2777 case -EINPROGRESS:
2778 r->res_first_lkid = 0;
2779 process_lookup_list(r);
2780 break;
2781
2782 case -EAGAIN:
2783 case -EBADR:
2784 case -ENOTBLK:
2785 /* the remote request failed and won't be retried (it was
2786 a NOQUEUE, or has been canceled/unlocked); make a waiting
2787 lkb the first_lkid */
2788
2789 r->res_first_lkid = 0;
2790
2791 if (!list_empty(&r->res_lookup)) {
2792 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2793 lkb_rsb_lookup);
2794 list_del_init(&lkb->lkb_rsb_lookup);
2795 r->res_first_lkid = lkb->lkb_id;
2796 _request_lock(r, lkb);
2797 }
2798 break;
2799
2800 default:
2801 log_error(r->res_ls, "confirm_master unknown error %d", error);
2802 }
2803}
2804
2805static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
2806 int namelen, unsigned long timeout_cs,
2807 void (*ast) (void *astparam),
2808 void *astparam,
2809 void (*bast) (void *astparam, int mode),
2810 struct dlm_args *args)
2811{
2812 int rv = -EINVAL;
2813
2814 /* check for invalid arg usage */
2815
2816 if (mode < 0 || mode > DLM_LOCK_EX)
2817 goto out;
2818
2819 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2820 goto out;
2821
2822 if (flags & DLM_LKF_CANCEL)
2823 goto out;
2824
2825 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2826 goto out;
2827
2828 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2829 goto out;
2830
2831 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2832 goto out;
2833
2834 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2835 goto out;
2836
2837 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2838 goto out;
2839
2840 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2841 goto out;
2842
2843 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2844 goto out;
2845
2846 if (!ast || !lksb)
2847 goto out;
2848
2849 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2850 goto out;
2851
2852 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2853 goto out;
2854
2855 /* these args will be copied to the lkb in validate_lock_args,
2856 it cannot be done now because when converting locks, fields in
2857 an active lkb cannot be modified before locking the rsb */
2858
2859 args->flags = flags;
2860 args->astfn = ast;
2861 args->astparam = astparam;
2862 args->bastfn = bast;
2863 args->timeout = timeout_cs;
2864 args->mode = mode;
2865 args->lksb = lksb;
2866 rv = 0;
2867 out:
2868 return rv;
2869}
2870
2871static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2872{
2873 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2874 DLM_LKF_FORCEUNLOCK))
2875 return -EINVAL;
2876
2877 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2878 return -EINVAL;
2879
2880 args->flags = flags;
2881 args->astparam = astarg;
2882 return 0;
2883}
2884
2885static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2886 struct dlm_args *args)
2887{
2888 int rv = -EINVAL;
2889
2890 if (args->flags & DLM_LKF_CONVERT) {
2891 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2892 goto out;
2893
2894 if (args->flags & DLM_LKF_QUECVT &&
2895 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2896 goto out;
2897
2898 rv = -EBUSY;
2899 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2900 goto out;
2901
2902 if (lkb->lkb_wait_type)
2903 goto out;
2904
2905 if (is_overlap(lkb))
2906 goto out;
2907 }
2908
2909 lkb->lkb_exflags = args->flags;
2910 lkb->lkb_sbflags = 0;
2911 lkb->lkb_astfn = args->astfn;
2912 lkb->lkb_astparam = args->astparam;
2913 lkb->lkb_bastfn = args->bastfn;
2914 lkb->lkb_rqmode = args->mode;
2915 lkb->lkb_lksb = args->lksb;
2916 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2917 lkb->lkb_ownpid = (int) current->pid;
2918 lkb->lkb_timeout_cs = args->timeout;
2919 rv = 0;
2920 out:
2921 if (rv)
2922 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2923 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2924 lkb->lkb_status, lkb->lkb_wait_type,
2925 lkb->lkb_resource->res_name);
2926 return rv;
2927}
2928
2929/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2930 for success */
2931
2932/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2933 because there may be a lookup in progress and it's valid to do
2934 cancel/unlockf on it */
2935
2936static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2937{
2938 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
2939 int rv = -EINVAL;
2940
2941 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2942 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2943 dlm_print_lkb(lkb);
2944 goto out;
2945 }
2946
2947 /* an lkb may still exist even though the lock is EOL'ed due to a
2948 cancel, unlock or failed noqueue request; an app can't use these
2949 locks; return same error as if the lkid had not been found at all */
2950
2951 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2952 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2953 rv = -ENOENT;
2954 goto out;
2955 }
2956
2957 /* an lkb may be waiting for an rsb lookup to complete where the
2958 lookup was initiated by another lock */
2959
2960 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2961 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
2962 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2963 list_del_init(&lkb->lkb_rsb_lookup);
2964 queue_cast(lkb->lkb_resource, lkb,
2965 args->flags & DLM_LKF_CANCEL ?
2966 -DLM_ECANCEL : -DLM_EUNLOCK);
2967 unhold_lkb(lkb); /* undoes create_lkb() */
2968 }
2969 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2970 rv = -EBUSY;
2971 goto out;
2972 }
2973
2974 /* cancel not allowed with another cancel/unlock in progress */
2975
2976 if (args->flags & DLM_LKF_CANCEL) {
2977 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2978 goto out;
2979
2980 if (is_overlap(lkb))
2981 goto out;
2982
2983 /* don't let scand try to do a cancel */
2984 del_timeout(lkb);
2985
2986 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2987 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2988 rv = -EBUSY;
2989 goto out;
2990 }
2991
2992 /* there's nothing to cancel */
2993 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2994 !lkb->lkb_wait_type) {
2995 rv = -EBUSY;
2996 goto out;
2997 }
2998
2999 switch (lkb->lkb_wait_type) {
3000 case DLM_MSG_LOOKUP:
3001 case DLM_MSG_REQUEST:
3002 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
3003 rv = -EBUSY;
3004 goto out;
3005 case DLM_MSG_UNLOCK:
3006 case DLM_MSG_CANCEL:
3007 goto out;
3008 }
3009 /* add_to_waiters() will set OVERLAP_CANCEL */
3010 goto out_ok;
3011 }
3012
3013 /* do we need to allow a force-unlock if there's a normal unlock
3014 already in progress? in what conditions could the normal unlock
3015 fail such that we'd want to send a force-unlock to be sure? */
3016
3017 if (args->flags & DLM_LKF_FORCEUNLOCK) {
3018 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
3019 goto out;
3020
3021 if (is_overlap_unlock(lkb))
3022 goto out;
3023
3024 /* don't let scand try to do a cancel */
3025 del_timeout(lkb);
3026
3027 if (lkb->lkb_flags & DLM_IFL_RESEND) {
3028 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3029 rv = -EBUSY;
3030 goto out;
3031 }
3032
3033 switch (lkb->lkb_wait_type) {
3034 case DLM_MSG_LOOKUP:
3035 case DLM_MSG_REQUEST:
3036 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3037 rv = -EBUSY;
3038 goto out;
3039 case DLM_MSG_UNLOCK:
3040 goto out;
3041 }
3042 /* add_to_waiters() will set OVERLAP_UNLOCK */
3043 goto out_ok;
3044 }
3045
3046 /* normal unlock not allowed if there's any op in progress */
3047 rv = -EBUSY;
3048 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
3049 goto out;
3050
3051 out_ok:
3052 /* an overlapping op shouldn't blow away exflags from other op */
3053 lkb->lkb_exflags |= args->flags;
3054 lkb->lkb_sbflags = 0;
3055 lkb->lkb_astparam = args->astparam;
3056 rv = 0;
3057 out:
3058 if (rv)
3059 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
3060 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
3061 args->flags, lkb->lkb_wait_type,
3062 lkb->lkb_resource->res_name);
3063 return rv;
3064}
3065
3066/*
3067 * Four stage 4 varieties:
3068 * do_request(), do_convert(), do_unlock(), do_cancel()
3069 * These are called on the master node for the given lock and
3070 * from the central locking logic.
3071 */
3072
3073static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3074{
3075 int error = 0;
3076
3077 if (can_be_granted(r, lkb, 1, 0, NULL)) {
3078 grant_lock(r, lkb);
3079 queue_cast(r, lkb, 0);
3080 goto out;
3081 }
3082
3083 if (can_be_queued(lkb)) {
3084 error = -EINPROGRESS;
3085 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3086 add_timeout(lkb);
3087 goto out;
3088 }
3089
3090 error = -EAGAIN;
3091 queue_cast(r, lkb, -EAGAIN);
3092 out:
3093 return error;
3094}
3095
3096static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3097 int error)
3098{
3099 switch (error) {
3100 case -EAGAIN:
3101 if (force_blocking_asts(lkb))
3102 send_blocking_asts_all(r, lkb);
3103 break;
3104 case -EINPROGRESS:
3105 send_blocking_asts(r, lkb);
3106 break;
3107 }
3108}
3109
3110static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3111{
3112 int error = 0;
3113 int deadlk = 0;
3114
3115 /* changing an existing lock may allow others to be granted */
3116
3117 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
3118 grant_lock(r, lkb);
3119 queue_cast(r, lkb, 0);
3120 goto out;
3121 }
3122
3123 /* can_be_granted() detected that this lock would block in a conversion
3124 deadlock, so we leave it on the granted queue and return EDEADLK in
3125 the ast for the convert. */
3126
3127 if (deadlk) {
3128 /* it's left on the granted queue */
3129 revert_lock(r, lkb);
3130 queue_cast(r, lkb, -EDEADLK);
3131 error = -EDEADLK;
3132 goto out;
3133 }
3134
3135 /* is_demoted() means the can_be_granted() above set the grmode
3136 to NL, and left us on the granted queue. This auto-demotion
3137 (due to CONVDEADLK) might mean other locks, and/or this lock, are
3138 now grantable. We have to try to grant other converting locks
3139 before we try again to grant this one. */
3140
3141 if (is_demoted(lkb)) {
3142 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
3143 if (_can_be_granted(r, lkb, 1, 0)) {
3144 grant_lock(r, lkb);
3145 queue_cast(r, lkb, 0);
3146 goto out;
3147 }
3148 /* else fall through and move to convert queue */
3149 }
3150
3151 if (can_be_queued(lkb)) {
3152 error = -EINPROGRESS;
3153 del_lkb(r, lkb);
3154 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3155 add_timeout(lkb);
3156 goto out;
3157 }
3158
3159 error = -EAGAIN;
3160 queue_cast(r, lkb, -EAGAIN);
3161 out:
3162 return error;
3163}
3164
3165static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3166 int error)
3167{
3168 switch (error) {
3169 case 0:
3170 grant_pending_locks(r, NULL);
3171 /* grant_pending_locks also sends basts */
3172 break;
3173 case -EAGAIN:
3174 if (force_blocking_asts(lkb))
3175 send_blocking_asts_all(r, lkb);
3176 break;
3177 case -EINPROGRESS:
3178 send_blocking_asts(r, lkb);
3179 break;
3180 }
3181}
3182
3183static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3184{
3185 remove_lock(r, lkb);
3186 queue_cast(r, lkb, -DLM_EUNLOCK);
3187 return -DLM_EUNLOCK;
3188}
3189
3190static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3191 int error)
3192{
3193 grant_pending_locks(r, NULL);
3194}
3195
3196/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
3197
3198static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3199{
3200 int error;
3201
3202 error = revert_lock(r, lkb);
3203 if (error) {
3204 queue_cast(r, lkb, -DLM_ECANCEL);
3205 return -DLM_ECANCEL;
3206 }
3207 return 0;
3208}
3209
3210static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3211 int error)
3212{
3213 if (error)
3214 grant_pending_locks(r, NULL);
3215}
3216
3217/*
3218 * Four stage 3 varieties:
3219 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3220 */
3221
3222/* add a new lkb to a possibly new rsb, called by requesting process */
3223
3224static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3225{
3226 int error;
3227
3228 /* set_master: sets lkb nodeid from r */
3229
3230 error = set_master(r, lkb);
3231 if (error < 0)
3232 goto out;
3233 if (error) {
3234 error = 0;
3235 goto out;
3236 }
3237
3238 if (is_remote(r)) {
3239 /* receive_request() calls do_request() on remote node */
3240 error = send_request(r, lkb);
3241 } else {
3242 error = do_request(r, lkb);
3243 /* for remote locks the request_reply is sent
3244 between do_request and do_request_effects */
3245 do_request_effects(r, lkb, error);
3246 }
3247 out:
3248 return error;
3249}
3250
3251/* change some property of an existing lkb, e.g. mode */
3252
3253static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3254{
3255 int error;
3256
3257 if (is_remote(r)) {
3258 /* receive_convert() calls do_convert() on remote node */
3259 error = send_convert(r, lkb);
3260 } else {
3261 error = do_convert(r, lkb);
3262 /* for remote locks the convert_reply is sent
3263 between do_convert and do_convert_effects */
3264 do_convert_effects(r, lkb, error);
3265 }
3266
3267 return error;
3268}
3269
3270/* remove an existing lkb from the granted queue */
3271
3272static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3273{
3274 int error;
3275
3276 if (is_remote(r)) {
3277 /* receive_unlock() calls do_unlock() on remote node */
3278 error = send_unlock(r, lkb);
3279 } else {
3280 error = do_unlock(r, lkb);
3281 /* for remote locks the unlock_reply is sent
3282 between do_unlock and do_unlock_effects */
3283 do_unlock_effects(r, lkb, error);
3284 }
3285
3286 return error;
3287}
3288
3289/* remove an existing lkb from the convert or wait queue */
3290
3291static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3292{
3293 int error;
3294
3295 if (is_remote(r)) {
3296 /* receive_cancel() calls do_cancel() on remote node */
3297 error = send_cancel(r, lkb);
3298 } else {
3299 error = do_cancel(r, lkb);
3300 /* for remote locks the cancel_reply is sent
3301 between do_cancel and do_cancel_effects */
3302 do_cancel_effects(r, lkb, error);
3303 }
3304
3305 return error;
3306}
3307
3308/*
3309 * Four stage 2 varieties:
3310 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3311 */
3312
3313static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
3314 int len, struct dlm_args *args)
3315{
3316 struct dlm_rsb *r;
3317 int error;
3318
3319 error = validate_lock_args(ls, lkb, args);
3320 if (error)
3321 return error;
3322
3323 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
3324 if (error)
3325 return error;
3326
3327 lock_rsb(r);
3328
3329 attach_lkb(r, lkb);
3330 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3331
3332 error = _request_lock(r, lkb);
3333
3334 unlock_rsb(r);
3335 put_rsb(r);
3336 return error;
3337}
3338
3339static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3340 struct dlm_args *args)
3341{
3342 struct dlm_rsb *r;
3343 int error;
3344
3345 r = lkb->lkb_resource;
3346
3347 hold_rsb(r);
3348 lock_rsb(r);
3349
3350 error = validate_lock_args(ls, lkb, args);
3351 if (error)
3352 goto out;
3353
3354 error = _convert_lock(r, lkb);
3355 out:
3356 unlock_rsb(r);
3357 put_rsb(r);
3358 return error;
3359}
3360
3361static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3362 struct dlm_args *args)
3363{
3364 struct dlm_rsb *r;
3365 int error;
3366
3367 r = lkb->lkb_resource;
3368
3369 hold_rsb(r);
3370 lock_rsb(r);
3371
3372 error = validate_unlock_args(lkb, args);
3373 if (error)
3374 goto out;
3375
3376 error = _unlock_lock(r, lkb);
3377 out:
3378 unlock_rsb(r);
3379 put_rsb(r);
3380 return error;
3381}
3382
3383static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3384 struct dlm_args *args)
3385{
3386 struct dlm_rsb *r;
3387 int error;
3388
3389 r = lkb->lkb_resource;
3390
3391 hold_rsb(r);
3392 lock_rsb(r);
3393
3394 error = validate_unlock_args(lkb, args);
3395 if (error)
3396 goto out;
3397
3398 error = _cancel_lock(r, lkb);
3399 out:
3400 unlock_rsb(r);
3401 put_rsb(r);
3402 return error;
3403}
3404
3405/*
3406 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3407 */
3408
3409int dlm_lock(dlm_lockspace_t *lockspace,
3410 int mode,
3411 struct dlm_lksb *lksb,
3412 uint32_t flags,
3413 void *name,
3414 unsigned int namelen,
3415 uint32_t parent_lkid,
3416 void (*ast) (void *astarg),
3417 void *astarg,
3418 void (*bast) (void *astarg, int mode))
3419{
3420 struct dlm_ls *ls;
3421 struct dlm_lkb *lkb;
3422 struct dlm_args args;
3423 int error, convert = flags & DLM_LKF_CONVERT;
3424
3425 ls = dlm_find_lockspace_local(lockspace);
3426 if (!ls)
3427 return -EINVAL;
3428
3429 dlm_lock_recovery(ls);
3430
3431 if (convert)
3432 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3433 else
3434 error = create_lkb(ls, &lkb);
3435
3436 if (error)
3437 goto out;
3438
3439 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3440 astarg, bast, &args);
3441 if (error)
3442 goto out_put;
3443
3444 if (convert)
3445 error = convert_lock(ls, lkb, &args);
3446 else
3447 error = request_lock(ls, lkb, name, namelen, &args);
3448
3449 if (error == -EINPROGRESS)
3450 error = 0;
3451 out_put:
3452 if (convert || error)
3453 __put_lkb(ls, lkb);
3454 if (error == -EAGAIN || error == -EDEADLK)
3455 error = 0;
3456 out:
3457 dlm_unlock_recovery(ls);
3458 dlm_put_lockspace(ls);
3459 return error;
3460}
3461
3462int dlm_unlock(dlm_lockspace_t *lockspace,
3463 uint32_t lkid,
3464 uint32_t flags,
3465 struct dlm_lksb *lksb,
3466 void *astarg)
3467{
3468 struct dlm_ls *ls;
3469 struct dlm_lkb *lkb;
3470 struct dlm_args args;
3471 int error;
3472
3473 ls = dlm_find_lockspace_local(lockspace);
3474 if (!ls)
3475 return -EINVAL;
3476
3477 dlm_lock_recovery(ls);
3478
3479 error = find_lkb(ls, lkid, &lkb);
3480 if (error)
3481 goto out;
3482
3483 error = set_unlock_args(flags, astarg, &args);
3484 if (error)
3485 goto out_put;
3486
3487 if (flags & DLM_LKF_CANCEL)
3488 error = cancel_lock(ls, lkb, &args);
3489 else
3490 error = unlock_lock(ls, lkb, &args);
3491
3492 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3493 error = 0;
3494 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3495 error = 0;
3496 out_put:
3497 dlm_put_lkb(lkb);
3498 out:
3499 dlm_unlock_recovery(ls);
3500 dlm_put_lockspace(ls);
3501 return error;
3502}
3503
3504/*
3505 * send/receive routines for remote operations and replies
3506 *
3507 * send_args
3508 * send_common
3509 * send_request receive_request
3510 * send_convert receive_convert
3511 * send_unlock receive_unlock
3512 * send_cancel receive_cancel
3513 * send_grant receive_grant
3514 * send_bast receive_bast
3515 * send_lookup receive_lookup
3516 * send_remove receive_remove
3517 *
3518 * send_common_reply
3519 * receive_request_reply send_request_reply
3520 * receive_convert_reply send_convert_reply
3521 * receive_unlock_reply send_unlock_reply
3522 * receive_cancel_reply send_cancel_reply
3523 * receive_lookup_reply send_lookup_reply
3524 */
3525
3526static int _create_message(struct dlm_ls *ls, int mb_len,
3527 int to_nodeid, int mstype,
3528 struct dlm_message **ms_ret,
3529 struct dlm_mhandle **mh_ret)
3530{
3531 struct dlm_message *ms;
3532 struct dlm_mhandle *mh;
3533 char *mb;
3534
3535 /* get_buffer gives us a message handle (mh) that we need to
3536 pass into lowcomms_commit and a message buffer (mb) that we
3537 write our data into */
3538
3539 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
3540 if (!mh)
3541 return -ENOBUFS;
3542
3543 memset(mb, 0, mb_len);
3544
3545 ms = (struct dlm_message *) mb;
3546
3547 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
3548 ms->m_header.h_lockspace = ls->ls_global_id;
3549 ms->m_header.h_nodeid = dlm_our_nodeid();
3550 ms->m_header.h_length = mb_len;
3551 ms->m_header.h_cmd = DLM_MSG;
3552
3553 ms->m_type = mstype;
3554
3555 *mh_ret = mh;
3556 *ms_ret = ms;
3557 return 0;
3558}
3559
3560static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3561 int to_nodeid, int mstype,
3562 struct dlm_message **ms_ret,
3563 struct dlm_mhandle **mh_ret)
3564{
3565 int mb_len = sizeof(struct dlm_message);
3566
3567 switch (mstype) {
3568 case DLM_MSG_REQUEST:
3569 case DLM_MSG_LOOKUP:
3570 case DLM_MSG_REMOVE:
3571 mb_len += r->res_length;
3572 break;
3573 case DLM_MSG_CONVERT:
3574 case DLM_MSG_UNLOCK:
3575 case DLM_MSG_REQUEST_REPLY:
3576 case DLM_MSG_CONVERT_REPLY:
3577 case DLM_MSG_GRANT:
3578 if (lkb && lkb->lkb_lvbptr)
3579 mb_len += r->res_ls->ls_lvblen;
3580 break;
3581 }
3582
3583 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3584 ms_ret, mh_ret);
3585}
3586
3587/* further lowcomms enhancements or alternate implementations may make
3588 the return value from this function useful at some point */
3589
3590static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
3591{
3592 dlm_message_out(ms);
3593 dlm_lowcomms_commit_buffer(mh);
3594 return 0;
3595}
3596
3597static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3598 struct dlm_message *ms)
3599{
3600 ms->m_nodeid = lkb->lkb_nodeid;
3601 ms->m_pid = lkb->lkb_ownpid;
3602 ms->m_lkid = lkb->lkb_id;
3603 ms->m_remid = lkb->lkb_remid;
3604 ms->m_exflags = lkb->lkb_exflags;
3605 ms->m_sbflags = lkb->lkb_sbflags;
3606 ms->m_flags = lkb->lkb_flags;
3607 ms->m_lvbseq = lkb->lkb_lvbseq;
3608 ms->m_status = lkb->lkb_status;
3609 ms->m_grmode = lkb->lkb_grmode;
3610 ms->m_rqmode = lkb->lkb_rqmode;
3611 ms->m_hash = r->res_hash;
3612
3613 /* m_result and m_bastmode are set from function args,
3614 not from lkb fields */
3615
3616 if (lkb->lkb_bastfn)
3617 ms->m_asts |= DLM_CB_BAST;
3618 if (lkb->lkb_astfn)
3619 ms->m_asts |= DLM_CB_CAST;
3620
3621 /* compare with switch in create_message; send_remove() doesn't
3622 use send_args() */
3623
3624 switch (ms->m_type) {
3625 case DLM_MSG_REQUEST:
3626 case DLM_MSG_LOOKUP:
3627 memcpy(ms->m_extra, r->res_name, r->res_length);
3628 break;
3629 case DLM_MSG_CONVERT:
3630 case DLM_MSG_UNLOCK:
3631 case DLM_MSG_REQUEST_REPLY:
3632 case DLM_MSG_CONVERT_REPLY:
3633 case DLM_MSG_GRANT:
3634 if (!lkb->lkb_lvbptr)
3635 break;
3636 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
3637 break;
3638 }
3639}
3640
3641static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3642{
3643 struct dlm_message *ms;
3644 struct dlm_mhandle *mh;
3645 int to_nodeid, error;
3646
3647 to_nodeid = r->res_nodeid;
3648
3649 error = add_to_waiters(lkb, mstype, to_nodeid);
3650 if (error)
3651 return error;
3652
3653 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3654 if (error)
3655 goto fail;
3656
3657 send_args(r, lkb, ms);
3658
3659 error = send_message(mh, ms);
3660 if (error)
3661 goto fail;
3662 return 0;
3663
3664 fail:
3665 remove_from_waiters(lkb, msg_reply_type(mstype));
3666 return error;
3667}
3668
3669static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3670{
3671 return send_common(r, lkb, DLM_MSG_REQUEST);
3672}
3673
3674static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3675{
3676 int error;
3677
3678 error = send_common(r, lkb, DLM_MSG_CONVERT);
3679
3680 /* down conversions go without a reply from the master */
3681 if (!error && down_conversion(lkb)) {
3682 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
3683 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
3684 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
3685 r->res_ls->ls_stub_ms.m_result = 0;
3686 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3687 }
3688
3689 return error;
3690}
3691
3692/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3693 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3694 that the master is still correct. */
3695
3696static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3697{
3698 return send_common(r, lkb, DLM_MSG_UNLOCK);
3699}
3700
3701static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3702{
3703 return send_common(r, lkb, DLM_MSG_CANCEL);
3704}
3705
3706static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3707{
3708 struct dlm_message *ms;
3709 struct dlm_mhandle *mh;
3710 int to_nodeid, error;
3711
3712 to_nodeid = lkb->lkb_nodeid;
3713
3714 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3715 if (error)
3716 goto out;
3717
3718 send_args(r, lkb, ms);
3719
3720 ms->m_result = 0;
3721
3722 error = send_message(mh, ms);
3723 out:
3724 return error;
3725}
3726
3727static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3728{
3729 struct dlm_message *ms;
3730 struct dlm_mhandle *mh;
3731 int to_nodeid, error;
3732
3733 to_nodeid = lkb->lkb_nodeid;
3734
3735 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3736 if (error)
3737 goto out;
3738
3739 send_args(r, lkb, ms);
3740
3741 ms->m_bastmode = mode;
3742
3743 error = send_message(mh, ms);
3744 out:
3745 return error;
3746}
3747
3748static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3749{
3750 struct dlm_message *ms;
3751 struct dlm_mhandle *mh;
3752 int to_nodeid, error;
3753
3754 to_nodeid = dlm_dir_nodeid(r);
3755
3756 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
3757 if (error)
3758 return error;
3759
3760 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3761 if (error)
3762 goto fail;
3763
3764 send_args(r, lkb, ms);
3765
3766 error = send_message(mh, ms);
3767 if (error)
3768 goto fail;
3769 return 0;
3770
3771 fail:
3772 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3773 return error;
3774}
3775
3776static int send_remove(struct dlm_rsb *r)
3777{
3778 struct dlm_message *ms;
3779 struct dlm_mhandle *mh;
3780 int to_nodeid, error;
3781
3782 to_nodeid = dlm_dir_nodeid(r);
3783
3784 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3785 if (error)
3786 goto out;
3787
3788 memcpy(ms->m_extra, r->res_name, r->res_length);
3789 ms->m_hash = r->res_hash;
3790
3791 error = send_message(mh, ms);
3792 out:
3793 return error;
3794}
3795
3796static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3797 int mstype, int rv)
3798{
3799 struct dlm_message *ms;
3800 struct dlm_mhandle *mh;
3801 int to_nodeid, error;
3802
3803 to_nodeid = lkb->lkb_nodeid;
3804
3805 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3806 if (error)
3807 goto out;
3808
3809 send_args(r, lkb, ms);
3810
3811 ms->m_result = rv;
3812
3813 error = send_message(mh, ms);
3814 out:
3815 return error;
3816}
3817
3818static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3819{
3820 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3821}
3822
3823static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3824{
3825 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3826}
3827
3828static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3829{
3830 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3831}
3832
3833static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3834{
3835 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3836}
3837
3838static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3839 int ret_nodeid, int rv)
3840{
3841 struct dlm_rsb *r = &ls->ls_stub_rsb;
3842 struct dlm_message *ms;
3843 struct dlm_mhandle *mh;
3844 int error, nodeid = ms_in->m_header.h_nodeid;
3845
3846 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3847 if (error)
3848 goto out;
3849
3850 ms->m_lkid = ms_in->m_lkid;
3851 ms->m_result = rv;
3852 ms->m_nodeid = ret_nodeid;
3853
3854 error = send_message(mh, ms);
3855 out:
3856 return error;
3857}
3858
3859/* which args we save from a received message depends heavily on the type
3860 of message, unlike the send side where we can safely send everything about
3861 the lkb for any type of message */
3862
3863static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3864{
3865 lkb->lkb_exflags = ms->m_exflags;
3866 lkb->lkb_sbflags = ms->m_sbflags;
3867 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3868 (ms->m_flags & 0x0000FFFF);
3869}
3870
3871static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3872{
3873 if (ms->m_flags == DLM_IFL_STUB_MS)
3874 return;
3875
3876 lkb->lkb_sbflags = ms->m_sbflags;
3877 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3878 (ms->m_flags & 0x0000FFFF);
3879}
3880
3881static int receive_extralen(struct dlm_message *ms)
3882{
3883 return (ms->m_header.h_length - sizeof(struct dlm_message));
3884}
3885
3886static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3887 struct dlm_message *ms)
3888{
3889 int len;
3890
3891 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3892 if (!lkb->lkb_lvbptr)
3893 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3894 if (!lkb->lkb_lvbptr)
3895 return -ENOMEM;
3896 len = receive_extralen(ms);
3897 if (len > ls->ls_lvblen)
3898 len = ls->ls_lvblen;
3899 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3900 }
3901 return 0;
3902}
3903
3904static void fake_bastfn(void *astparam, int mode)
3905{
3906 log_print("fake_bastfn should not be called");
3907}
3908
3909static void fake_astfn(void *astparam)
3910{
3911 log_print("fake_astfn should not be called");
3912}
3913
3914static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3915 struct dlm_message *ms)
3916{
3917 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3918 lkb->lkb_ownpid = ms->m_pid;
3919 lkb->lkb_remid = ms->m_lkid;
3920 lkb->lkb_grmode = DLM_LOCK_IV;
3921 lkb->lkb_rqmode = ms->m_rqmode;
3922
3923 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3924 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
3925
3926 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3927 /* lkb was just created so there won't be an lvb yet */
3928 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3929 if (!lkb->lkb_lvbptr)
3930 return -ENOMEM;
3931 }
3932
3933 return 0;
3934}
3935
3936static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3937 struct dlm_message *ms)
3938{
3939 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3940 return -EBUSY;
3941
3942 if (receive_lvb(ls, lkb, ms))
3943 return -ENOMEM;
3944
3945 lkb->lkb_rqmode = ms->m_rqmode;
3946 lkb->lkb_lvbseq = ms->m_lvbseq;
3947
3948 return 0;
3949}
3950
3951static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3952 struct dlm_message *ms)
3953{
3954 if (receive_lvb(ls, lkb, ms))
3955 return -ENOMEM;
3956 return 0;
3957}
3958
3959/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3960 uses to send a reply and that the remote end uses to process the reply. */
3961
3962static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3963{
3964 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3965 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3966 lkb->lkb_remid = ms->m_lkid;
3967}
3968
3969/* This is called after the rsb is locked so that we can safely inspect
3970 fields in the lkb. */
3971
3972static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3973{
3974 int from = ms->m_header.h_nodeid;
3975 int error = 0;
3976
3977 switch (ms->m_type) {
3978 case DLM_MSG_CONVERT:
3979 case DLM_MSG_UNLOCK:
3980 case DLM_MSG_CANCEL:
3981 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3982 error = -EINVAL;
3983 break;
3984
3985 case DLM_MSG_CONVERT_REPLY:
3986 case DLM_MSG_UNLOCK_REPLY:
3987 case DLM_MSG_CANCEL_REPLY:
3988 case DLM_MSG_GRANT:
3989 case DLM_MSG_BAST:
3990 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3991 error = -EINVAL;
3992 break;
3993
3994 case DLM_MSG_REQUEST_REPLY:
3995 if (!is_process_copy(lkb))
3996 error = -EINVAL;
3997 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3998 error = -EINVAL;
3999 break;
4000
4001 default:
4002 error = -EINVAL;
4003 }
4004
4005 if (error)
4006 log_error(lkb->lkb_resource->res_ls,
4007 "ignore invalid message %d from %d %x %x %x %d",
4008 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
4009 lkb->lkb_flags, lkb->lkb_nodeid);
4010 return error;
4011}
4012
4013static void send_repeat_remove(struct dlm_ls *ls, char *ms_name, int len)
4014{
4015 char name[DLM_RESNAME_MAXLEN + 1];
4016 struct dlm_message *ms;
4017 struct dlm_mhandle *mh;
4018 struct dlm_rsb *r;
4019 uint32_t hash, b;
4020 int rv, dir_nodeid;
4021
4022 memset(name, 0, sizeof(name));
4023 memcpy(name, ms_name, len);
4024
4025 hash = jhash(name, len, 0);
4026 b = hash & (ls->ls_rsbtbl_size - 1);
4027
4028 dir_nodeid = dlm_hash2nodeid(ls, hash);
4029
4030 log_error(ls, "send_repeat_remove dir %d %s", dir_nodeid, name);
4031
4032 spin_lock(&ls->ls_rsbtbl[b].lock);
4033 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4034 if (!rv) {
4035 spin_unlock(&ls->ls_rsbtbl[b].lock);
4036 log_error(ls, "repeat_remove on keep %s", name);
4037 return;
4038 }
4039
4040 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4041 if (!rv) {
4042 spin_unlock(&ls->ls_rsbtbl[b].lock);
4043 log_error(ls, "repeat_remove on toss %s", name);
4044 return;
4045 }
4046
4047 /* use ls->remove_name2 to avoid conflict with shrink? */
4048
4049 spin_lock(&ls->ls_remove_spin);
4050 ls->ls_remove_len = len;
4051 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
4052 spin_unlock(&ls->ls_remove_spin);
4053 spin_unlock(&ls->ls_rsbtbl[b].lock);
4054
4055 rv = _create_message(ls, sizeof(struct dlm_message) + len,
4056 dir_nodeid, DLM_MSG_REMOVE, &ms, &mh);
4057 if (rv)
4058 return;
4059
4060 memcpy(ms->m_extra, name, len);
4061 ms->m_hash = hash;
4062
4063 send_message(mh, ms);
4064
4065 spin_lock(&ls->ls_remove_spin);
4066 ls->ls_remove_len = 0;
4067 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
4068 spin_unlock(&ls->ls_remove_spin);
4069}
4070
4071static int receive_request(struct dlm_ls *ls, struct dlm_message *ms)
4072{
4073 struct dlm_lkb *lkb;
4074 struct dlm_rsb *r;
4075 int from_nodeid;
4076 int error, namelen = 0;
4077
4078 from_nodeid = ms->m_header.h_nodeid;
4079
4080 error = create_lkb(ls, &lkb);
4081 if (error)
4082 goto fail;
4083
4084 receive_flags(lkb, ms);
4085 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4086 error = receive_request_args(ls, lkb, ms);
4087 if (error) {
4088 __put_lkb(ls, lkb);
4089 goto fail;
4090 }
4091
4092 /* The dir node is the authority on whether we are the master
4093 for this rsb or not, so if the master sends us a request, we should
4094 recreate the rsb if we've destroyed it. This race happens when we
4095 send a remove message to the dir node at the same time that the dir
4096 node sends us a request for the rsb. */
4097
4098 namelen = receive_extralen(ms);
4099
4100 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
4101 R_RECEIVE_REQUEST, &r);
4102 if (error) {
4103 __put_lkb(ls, lkb);
4104 goto fail;
4105 }
4106
4107 lock_rsb(r);
4108
4109 if (r->res_master_nodeid != dlm_our_nodeid()) {
4110 error = validate_master_nodeid(ls, r, from_nodeid);
4111 if (error) {
4112 unlock_rsb(r);
4113 put_rsb(r);
4114 __put_lkb(ls, lkb);
4115 goto fail;
4116 }
4117 }
4118
4119 attach_lkb(r, lkb);
4120 error = do_request(r, lkb);
4121 send_request_reply(r, lkb, error);
4122 do_request_effects(r, lkb, error);
4123
4124 unlock_rsb(r);
4125 put_rsb(r);
4126
4127 if (error == -EINPROGRESS)
4128 error = 0;
4129 if (error)
4130 dlm_put_lkb(lkb);
4131 return 0;
4132
4133 fail:
4134 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
4135 and do this receive_request again from process_lookup_list once
4136 we get the lookup reply. This would avoid a many repeated
4137 ENOTBLK request failures when the lookup reply designating us
4138 as master is delayed. */
4139
4140 /* We could repeatedly return -EBADR here if our send_remove() is
4141 delayed in being sent/arriving/being processed on the dir node.
4142 Another node would repeatedly lookup up the master, and the dir
4143 node would continue returning our nodeid until our send_remove
4144 took effect.
4145
4146 We send another remove message in case our previous send_remove
4147 was lost/ignored/missed somehow. */
4148
4149 if (error != -ENOTBLK) {
4150 log_limit(ls, "receive_request %x from %d %d",
4151 ms->m_lkid, from_nodeid, error);
4152 }
4153
4154 if (namelen && error == -EBADR) {
4155 send_repeat_remove(ls, ms->m_extra, namelen);
4156 msleep(1000);
4157 }
4158
4159 setup_stub_lkb(ls, ms);
4160 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4161 return error;
4162}
4163
4164static int receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
4165{
4166 struct dlm_lkb *lkb;
4167 struct dlm_rsb *r;
4168 int error, reply = 1;
4169
4170 error = find_lkb(ls, ms->m_remid, &lkb);
4171 if (error)
4172 goto fail;
4173
4174 if (lkb->lkb_remid != ms->m_lkid) {
4175 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
4176 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
4177 (unsigned long long)lkb->lkb_recover_seq,
4178 ms->m_header.h_nodeid, ms->m_lkid);
4179 error = -ENOENT;
4180 goto fail;
4181 }
4182
4183 r = lkb->lkb_resource;
4184
4185 hold_rsb(r);
4186 lock_rsb(r);
4187
4188 error = validate_message(lkb, ms);
4189 if (error)
4190 goto out;
4191
4192 receive_flags(lkb, ms);
4193
4194 error = receive_convert_args(ls, lkb, ms);
4195 if (error) {
4196 send_convert_reply(r, lkb, error);
4197 goto out;
4198 }
4199
4200 reply = !down_conversion(lkb);
4201
4202 error = do_convert(r, lkb);
4203 if (reply)
4204 send_convert_reply(r, lkb, error);
4205 do_convert_effects(r, lkb, error);
4206 out:
4207 unlock_rsb(r);
4208 put_rsb(r);
4209 dlm_put_lkb(lkb);
4210 return 0;
4211
4212 fail:
4213 setup_stub_lkb(ls, ms);
4214 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4215 return error;
4216}
4217
4218static int receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
4219{
4220 struct dlm_lkb *lkb;
4221 struct dlm_rsb *r;
4222 int error;
4223
4224 error = find_lkb(ls, ms->m_remid, &lkb);
4225 if (error)
4226 goto fail;
4227
4228 if (lkb->lkb_remid != ms->m_lkid) {
4229 log_error(ls, "receive_unlock %x remid %x remote %d %x",
4230 lkb->lkb_id, lkb->lkb_remid,
4231 ms->m_header.h_nodeid, ms->m_lkid);
4232 error = -ENOENT;
4233 goto fail;
4234 }
4235
4236 r = lkb->lkb_resource;
4237
4238 hold_rsb(r);
4239 lock_rsb(r);
4240
4241 error = validate_message(lkb, ms);
4242 if (error)
4243 goto out;
4244
4245 receive_flags(lkb, ms);
4246
4247 error = receive_unlock_args(ls, lkb, ms);
4248 if (error) {
4249 send_unlock_reply(r, lkb, error);
4250 goto out;
4251 }
4252
4253 error = do_unlock(r, lkb);
4254 send_unlock_reply(r, lkb, error);
4255 do_unlock_effects(r, lkb, error);
4256 out:
4257 unlock_rsb(r);
4258 put_rsb(r);
4259 dlm_put_lkb(lkb);
4260 return 0;
4261
4262 fail:
4263 setup_stub_lkb(ls, ms);
4264 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4265 return error;
4266}
4267
4268static int receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
4269{
4270 struct dlm_lkb *lkb;
4271 struct dlm_rsb *r;
4272 int error;
4273
4274 error = find_lkb(ls, ms->m_remid, &lkb);
4275 if (error)
4276 goto fail;
4277
4278 receive_flags(lkb, ms);
4279
4280 r = lkb->lkb_resource;
4281
4282 hold_rsb(r);
4283 lock_rsb(r);
4284
4285 error = validate_message(lkb, ms);
4286 if (error)
4287 goto out;
4288
4289 error = do_cancel(r, lkb);
4290 send_cancel_reply(r, lkb, error);
4291 do_cancel_effects(r, lkb, error);
4292 out:
4293 unlock_rsb(r);
4294 put_rsb(r);
4295 dlm_put_lkb(lkb);
4296 return 0;
4297
4298 fail:
4299 setup_stub_lkb(ls, ms);
4300 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4301 return error;
4302}
4303
4304static int receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
4305{
4306 struct dlm_lkb *lkb;
4307 struct dlm_rsb *r;
4308 int error;
4309
4310 error = find_lkb(ls, ms->m_remid, &lkb);
4311 if (error)
4312 return error;
4313
4314 r = lkb->lkb_resource;
4315
4316 hold_rsb(r);
4317 lock_rsb(r);
4318
4319 error = validate_message(lkb, ms);
4320 if (error)
4321 goto out;
4322
4323 receive_flags_reply(lkb, ms);
4324 if (is_altmode(lkb))
4325 munge_altmode(lkb, ms);
4326 grant_lock_pc(r, lkb, ms);
4327 queue_cast(r, lkb, 0);
4328 out:
4329 unlock_rsb(r);
4330 put_rsb(r);
4331 dlm_put_lkb(lkb);
4332 return 0;
4333}
4334
4335static int receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
4336{
4337 struct dlm_lkb *lkb;
4338 struct dlm_rsb *r;
4339 int error;
4340
4341 error = find_lkb(ls, ms->m_remid, &lkb);
4342 if (error)
4343 return error;
4344
4345 r = lkb->lkb_resource;
4346
4347 hold_rsb(r);
4348 lock_rsb(r);
4349
4350 error = validate_message(lkb, ms);
4351 if (error)
4352 goto out;
4353
4354 queue_bast(r, lkb, ms->m_bastmode);
4355 lkb->lkb_highbast = ms->m_bastmode;
4356 out:
4357 unlock_rsb(r);
4358 put_rsb(r);
4359 dlm_put_lkb(lkb);
4360 return 0;
4361}
4362
4363static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
4364{
4365 int len, error, ret_nodeid, from_nodeid, our_nodeid;
4366
4367 from_nodeid = ms->m_header.h_nodeid;
4368 our_nodeid = dlm_our_nodeid();
4369
4370 len = receive_extralen(ms);
4371
4372 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4373 &ret_nodeid, NULL);
4374
4375 /* Optimization: we're master so treat lookup as a request */
4376 if (!error && ret_nodeid == our_nodeid) {
4377 receive_request(ls, ms);
4378 return;
4379 }
4380 send_lookup_reply(ls, ms, ret_nodeid, error);
4381}
4382
4383static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
4384{
4385 char name[DLM_RESNAME_MAXLEN+1];
4386 struct dlm_rsb *r;
4387 uint32_t hash, b;
4388 int rv, len, dir_nodeid, from_nodeid;
4389
4390 from_nodeid = ms->m_header.h_nodeid;
4391
4392 len = receive_extralen(ms);
4393
4394 if (len > DLM_RESNAME_MAXLEN) {
4395 log_error(ls, "receive_remove from %d bad len %d",
4396 from_nodeid, len);
4397 return;
4398 }
4399
4400 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
4401 if (dir_nodeid != dlm_our_nodeid()) {
4402 log_error(ls, "receive_remove from %d bad nodeid %d",
4403 from_nodeid, dir_nodeid);
4404 return;
4405 }
4406
4407 /* Look for name on rsbtbl.toss, if it's there, kill it.
4408 If it's on rsbtbl.keep, it's being used, and we should ignore this
4409 message. This is an expected race between the dir node sending a
4410 request to the master node at the same time as the master node sends
4411 a remove to the dir node. The resolution to that race is for the
4412 dir node to ignore the remove message, and the master node to
4413 recreate the master rsb when it gets a request from the dir node for
4414 an rsb it doesn't have. */
4415
4416 memset(name, 0, sizeof(name));
4417 memcpy(name, ms->m_extra, len);
4418
4419 hash = jhash(name, len, 0);
4420 b = hash & (ls->ls_rsbtbl_size - 1);
4421
4422 spin_lock(&ls->ls_rsbtbl[b].lock);
4423
4424 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4425 if (rv) {
4426 /* verify the rsb is on keep list per comment above */
4427 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4428 if (rv) {
4429 /* should not happen */
4430 log_error(ls, "receive_remove from %d not found %s",
4431 from_nodeid, name);
4432 spin_unlock(&ls->ls_rsbtbl[b].lock);
4433 return;
4434 }
4435 if (r->res_master_nodeid != from_nodeid) {
4436 /* should not happen */
4437 log_error(ls, "receive_remove keep from %d master %d",
4438 from_nodeid, r->res_master_nodeid);
4439 dlm_print_rsb(r);
4440 spin_unlock(&ls->ls_rsbtbl[b].lock);
4441 return;
4442 }
4443
4444 log_debug(ls, "receive_remove from %d master %d first %x %s",
4445 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4446 name);
4447 spin_unlock(&ls->ls_rsbtbl[b].lock);
4448 return;
4449 }
4450
4451 if (r->res_master_nodeid != from_nodeid) {
4452 log_error(ls, "receive_remove toss from %d master %d",
4453 from_nodeid, r->res_master_nodeid);
4454 dlm_print_rsb(r);
4455 spin_unlock(&ls->ls_rsbtbl[b].lock);
4456 return;
4457 }
4458
4459 if (kref_put(&r->res_ref, kill_rsb)) {
4460 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4461 spin_unlock(&ls->ls_rsbtbl[b].lock);
4462 dlm_free_rsb(r);
4463 } else {
4464 log_error(ls, "receive_remove from %d rsb ref error",
4465 from_nodeid);
4466 dlm_print_rsb(r);
4467 spin_unlock(&ls->ls_rsbtbl[b].lock);
4468 }
4469}
4470
4471static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
4472{
4473 do_purge(ls, ms->m_nodeid, ms->m_pid);
4474}
4475
4476static int receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
4477{
4478 struct dlm_lkb *lkb;
4479 struct dlm_rsb *r;
4480 int error, mstype, result;
4481 int from_nodeid = ms->m_header.h_nodeid;
4482
4483 error = find_lkb(ls, ms->m_remid, &lkb);
4484 if (error)
4485 return error;
4486
4487 r = lkb->lkb_resource;
4488 hold_rsb(r);
4489 lock_rsb(r);
4490
4491 error = validate_message(lkb, ms);
4492 if (error)
4493 goto out;
4494
4495 mstype = lkb->lkb_wait_type;
4496 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4497 if (error) {
4498 log_error(ls, "receive_request_reply %x remote %d %x result %d",
4499 lkb->lkb_id, from_nodeid, ms->m_lkid, ms->m_result);
4500 dlm_dump_rsb(r);
4501 goto out;
4502 }
4503
4504 /* Optimization: the dir node was also the master, so it took our
4505 lookup as a request and sent request reply instead of lookup reply */
4506 if (mstype == DLM_MSG_LOOKUP) {
4507 r->res_master_nodeid = from_nodeid;
4508 r->res_nodeid = from_nodeid;
4509 lkb->lkb_nodeid = from_nodeid;
4510 }
4511
4512 /* this is the value returned from do_request() on the master */
4513 result = ms->m_result;
4514
4515 switch (result) {
4516 case -EAGAIN:
4517 /* request would block (be queued) on remote master */
4518 queue_cast(r, lkb, -EAGAIN);
4519 confirm_master(r, -EAGAIN);
4520 unhold_lkb(lkb); /* undoes create_lkb() */
4521 break;
4522
4523 case -EINPROGRESS:
4524 case 0:
4525 /* request was queued or granted on remote master */
4526 receive_flags_reply(lkb, ms);
4527 lkb->lkb_remid = ms->m_lkid;
4528 if (is_altmode(lkb))
4529 munge_altmode(lkb, ms);
4530 if (result) {
4531 add_lkb(r, lkb, DLM_LKSTS_WAITING);
4532 add_timeout(lkb);
4533 } else {
4534 grant_lock_pc(r, lkb, ms);
4535 queue_cast(r, lkb, 0);
4536 }
4537 confirm_master(r, result);
4538 break;
4539
4540 case -EBADR:
4541 case -ENOTBLK:
4542 /* find_rsb failed to find rsb or rsb wasn't master */
4543 log_limit(ls, "receive_request_reply %x from %d %d "
4544 "master %d dir %d first %x %s", lkb->lkb_id,
4545 from_nodeid, result, r->res_master_nodeid,
4546 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4547
4548 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4549 r->res_master_nodeid != dlm_our_nodeid()) {
4550 /* cause _request_lock->set_master->send_lookup */
4551 r->res_master_nodeid = 0;
4552 r->res_nodeid = -1;
4553 lkb->lkb_nodeid = -1;
4554 }
4555
4556 if (is_overlap(lkb)) {
4557 /* we'll ignore error in cancel/unlock reply */
4558 queue_cast_overlap(r, lkb);
4559 confirm_master(r, result);
4560 unhold_lkb(lkb); /* undoes create_lkb() */
4561 } else {
4562 _request_lock(r, lkb);
4563
4564 if (r->res_master_nodeid == dlm_our_nodeid())
4565 confirm_master(r, 0);
4566 }
4567 break;
4568
4569 default:
4570 log_error(ls, "receive_request_reply %x error %d",
4571 lkb->lkb_id, result);
4572 }
4573
4574 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
4575 log_debug(ls, "receive_request_reply %x result %d unlock",
4576 lkb->lkb_id, result);
4577 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4578 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4579 send_unlock(r, lkb);
4580 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
4581 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4582 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4583 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4584 send_cancel(r, lkb);
4585 } else {
4586 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4587 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4588 }
4589 out:
4590 unlock_rsb(r);
4591 put_rsb(r);
4592 dlm_put_lkb(lkb);
4593 return 0;
4594}
4595
4596static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4597 struct dlm_message *ms)
4598{
4599 /* this is the value returned from do_convert() on the master */
4600 switch (ms->m_result) {
4601 case -EAGAIN:
4602 /* convert would block (be queued) on remote master */
4603 queue_cast(r, lkb, -EAGAIN);
4604 break;
4605
4606 case -EDEADLK:
4607 receive_flags_reply(lkb, ms);
4608 revert_lock_pc(r, lkb);
4609 queue_cast(r, lkb, -EDEADLK);
4610 break;
4611
4612 case -EINPROGRESS:
4613 /* convert was queued on remote master */
4614 receive_flags_reply(lkb, ms);
4615 if (is_demoted(lkb))
4616 munge_demoted(lkb);
4617 del_lkb(r, lkb);
4618 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
4619 add_timeout(lkb);
4620 break;
4621
4622 case 0:
4623 /* convert was granted on remote master */
4624 receive_flags_reply(lkb, ms);
4625 if (is_demoted(lkb))
4626 munge_demoted(lkb);
4627 grant_lock_pc(r, lkb, ms);
4628 queue_cast(r, lkb, 0);
4629 break;
4630
4631 default:
4632 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4633 lkb->lkb_id, ms->m_header.h_nodeid, ms->m_lkid,
4634 ms->m_result);
4635 dlm_print_rsb(r);
4636 dlm_print_lkb(lkb);
4637 }
4638}
4639
4640static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4641{
4642 struct dlm_rsb *r = lkb->lkb_resource;
4643 int error;
4644
4645 hold_rsb(r);
4646 lock_rsb(r);
4647
4648 error = validate_message(lkb, ms);
4649 if (error)
4650 goto out;
4651
4652 /* stub reply can happen with waiters_mutex held */
4653 error = remove_from_waiters_ms(lkb, ms);
4654 if (error)
4655 goto out;
4656
4657 __receive_convert_reply(r, lkb, ms);
4658 out:
4659 unlock_rsb(r);
4660 put_rsb(r);
4661}
4662
4663static int receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
4664{
4665 struct dlm_lkb *lkb;
4666 int error;
4667
4668 error = find_lkb(ls, ms->m_remid, &lkb);
4669 if (error)
4670 return error;
4671
4672 _receive_convert_reply(lkb, ms);
4673 dlm_put_lkb(lkb);
4674 return 0;
4675}
4676
4677static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4678{
4679 struct dlm_rsb *r = lkb->lkb_resource;
4680 int error;
4681
4682 hold_rsb(r);
4683 lock_rsb(r);
4684
4685 error = validate_message(lkb, ms);
4686 if (error)
4687 goto out;
4688
4689 /* stub reply can happen with waiters_mutex held */
4690 error = remove_from_waiters_ms(lkb, ms);
4691 if (error)
4692 goto out;
4693
4694 /* this is the value returned from do_unlock() on the master */
4695
4696 switch (ms->m_result) {
4697 case -DLM_EUNLOCK:
4698 receive_flags_reply(lkb, ms);
4699 remove_lock_pc(r, lkb);
4700 queue_cast(r, lkb, -DLM_EUNLOCK);
4701 break;
4702 case -ENOENT:
4703 break;
4704 default:
4705 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4706 lkb->lkb_id, ms->m_result);
4707 }
4708 out:
4709 unlock_rsb(r);
4710 put_rsb(r);
4711}
4712
4713static int receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
4714{
4715 struct dlm_lkb *lkb;
4716 int error;
4717
4718 error = find_lkb(ls, ms->m_remid, &lkb);
4719 if (error)
4720 return error;
4721
4722 _receive_unlock_reply(lkb, ms);
4723 dlm_put_lkb(lkb);
4724 return 0;
4725}
4726
4727static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4728{
4729 struct dlm_rsb *r = lkb->lkb_resource;
4730 int error;
4731
4732 hold_rsb(r);
4733 lock_rsb(r);
4734
4735 error = validate_message(lkb, ms);
4736 if (error)
4737 goto out;
4738
4739 /* stub reply can happen with waiters_mutex held */
4740 error = remove_from_waiters_ms(lkb, ms);
4741 if (error)
4742 goto out;
4743
4744 /* this is the value returned from do_cancel() on the master */
4745
4746 switch (ms->m_result) {
4747 case -DLM_ECANCEL:
4748 receive_flags_reply(lkb, ms);
4749 revert_lock_pc(r, lkb);
4750 queue_cast(r, lkb, -DLM_ECANCEL);
4751 break;
4752 case 0:
4753 break;
4754 default:
4755 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4756 lkb->lkb_id, ms->m_result);
4757 }
4758 out:
4759 unlock_rsb(r);
4760 put_rsb(r);
4761}
4762
4763static int receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
4764{
4765 struct dlm_lkb *lkb;
4766 int error;
4767
4768 error = find_lkb(ls, ms->m_remid, &lkb);
4769 if (error)
4770 return error;
4771
4772 _receive_cancel_reply(lkb, ms);
4773 dlm_put_lkb(lkb);
4774 return 0;
4775}
4776
4777static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
4778{
4779 struct dlm_lkb *lkb;
4780 struct dlm_rsb *r;
4781 int error, ret_nodeid;
4782 int do_lookup_list = 0;
4783
4784 error = find_lkb(ls, ms->m_lkid, &lkb);
4785 if (error) {
4786 log_error(ls, "receive_lookup_reply no lkid %x", ms->m_lkid);
4787 return;
4788 }
4789
4790 /* ms->m_result is the value returned by dlm_master_lookup on dir node
4791 FIXME: will a non-zero error ever be returned? */
4792
4793 r = lkb->lkb_resource;
4794 hold_rsb(r);
4795 lock_rsb(r);
4796
4797 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4798 if (error)
4799 goto out;
4800
4801 ret_nodeid = ms->m_nodeid;
4802
4803 /* We sometimes receive a request from the dir node for this
4804 rsb before we've received the dir node's loookup_reply for it.
4805 The request from the dir node implies we're the master, so we set
4806 ourself as master in receive_request_reply, and verify here that
4807 we are indeed the master. */
4808
4809 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4810 /* This should never happen */
4811 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4812 "master %d dir %d our %d first %x %s",
4813 lkb->lkb_id, ms->m_header.h_nodeid, ret_nodeid,
4814 r->res_master_nodeid, r->res_dir_nodeid,
4815 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4816 }
4817
4818 if (ret_nodeid == dlm_our_nodeid()) {
4819 r->res_master_nodeid = ret_nodeid;
4820 r->res_nodeid = 0;
4821 do_lookup_list = 1;
4822 r->res_first_lkid = 0;
4823 } else if (ret_nodeid == -1) {
4824 /* the remote node doesn't believe it's the dir node */
4825 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4826 lkb->lkb_id, ms->m_header.h_nodeid);
4827 r->res_master_nodeid = 0;
4828 r->res_nodeid = -1;
4829 lkb->lkb_nodeid = -1;
4830 } else {
4831 /* set_master() will set lkb_nodeid from r */
4832 r->res_master_nodeid = ret_nodeid;
4833 r->res_nodeid = ret_nodeid;
4834 }
4835
4836 if (is_overlap(lkb)) {
4837 log_debug(ls, "receive_lookup_reply %x unlock %x",
4838 lkb->lkb_id, lkb->lkb_flags);
4839 queue_cast_overlap(r, lkb);
4840 unhold_lkb(lkb); /* undoes create_lkb() */
4841 goto out_list;
4842 }
4843
4844 _request_lock(r, lkb);
4845
4846 out_list:
4847 if (do_lookup_list)
4848 process_lookup_list(r);
4849 out:
4850 unlock_rsb(r);
4851 put_rsb(r);
4852 dlm_put_lkb(lkb);
4853}
4854
4855static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4856 uint32_t saved_seq)
4857{
4858 int error = 0, noent = 0;
4859
4860 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
4861 log_limit(ls, "receive %d from non-member %d %x %x %d",
4862 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4863 ms->m_remid, ms->m_result);
4864 return;
4865 }
4866
4867 switch (ms->m_type) {
4868
4869 /* messages sent to a master node */
4870
4871 case DLM_MSG_REQUEST:
4872 error = receive_request(ls, ms);
4873 break;
4874
4875 case DLM_MSG_CONVERT:
4876 error = receive_convert(ls, ms);
4877 break;
4878
4879 case DLM_MSG_UNLOCK:
4880 error = receive_unlock(ls, ms);
4881 break;
4882
4883 case DLM_MSG_CANCEL:
4884 noent = 1;
4885 error = receive_cancel(ls, ms);
4886 break;
4887
4888 /* messages sent from a master node (replies to above) */
4889
4890 case DLM_MSG_REQUEST_REPLY:
4891 error = receive_request_reply(ls, ms);
4892 break;
4893
4894 case DLM_MSG_CONVERT_REPLY:
4895 error = receive_convert_reply(ls, ms);
4896 break;
4897
4898 case DLM_MSG_UNLOCK_REPLY:
4899 error = receive_unlock_reply(ls, ms);
4900 break;
4901
4902 case DLM_MSG_CANCEL_REPLY:
4903 error = receive_cancel_reply(ls, ms);
4904 break;
4905
4906 /* messages sent from a master node (only two types of async msg) */
4907
4908 case DLM_MSG_GRANT:
4909 noent = 1;
4910 error = receive_grant(ls, ms);
4911 break;
4912
4913 case DLM_MSG_BAST:
4914 noent = 1;
4915 error = receive_bast(ls, ms);
4916 break;
4917
4918 /* messages sent to a dir node */
4919
4920 case DLM_MSG_LOOKUP:
4921 receive_lookup(ls, ms);
4922 break;
4923
4924 case DLM_MSG_REMOVE:
4925 receive_remove(ls, ms);
4926 break;
4927
4928 /* messages sent from a dir node (remove has no reply) */
4929
4930 case DLM_MSG_LOOKUP_REPLY:
4931 receive_lookup_reply(ls, ms);
4932 break;
4933
4934 /* other messages */
4935
4936 case DLM_MSG_PURGE:
4937 receive_purge(ls, ms);
4938 break;
4939
4940 default:
4941 log_error(ls, "unknown message type %d", ms->m_type);
4942 }
4943
4944 /*
4945 * When checking for ENOENT, we're checking the result of
4946 * find_lkb(m_remid):
4947 *
4948 * The lock id referenced in the message wasn't found. This may
4949 * happen in normal usage for the async messages and cancel, so
4950 * only use log_debug for them.
4951 *
4952 * Some errors are expected and normal.
4953 */
4954
4955 if (error == -ENOENT && noent) {
4956 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
4957 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4958 ms->m_lkid, saved_seq);
4959 } else if (error == -ENOENT) {
4960 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
4961 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4962 ms->m_lkid, saved_seq);
4963
4964 if (ms->m_type == DLM_MSG_CONVERT)
4965 dlm_dump_rsb_hash(ls, ms->m_hash);
4966 }
4967
4968 if (error == -EINVAL) {
4969 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4970 "saved_seq %u",
4971 ms->m_type, ms->m_header.h_nodeid,
4972 ms->m_lkid, ms->m_remid, saved_seq);
4973 }
4974}
4975
4976/* If the lockspace is in recovery mode (locking stopped), then normal
4977 messages are saved on the requestqueue for processing after recovery is
4978 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4979 messages off the requestqueue before we process new ones. This occurs right
4980 after recovery completes when we transition from saving all messages on
4981 requestqueue, to processing all the saved messages, to processing new
4982 messages as they arrive. */
4983
4984static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4985 int nodeid)
4986{
4987 if (dlm_locking_stopped(ls)) {
4988 /* If we were a member of this lockspace, left, and rejoined,
4989 other nodes may still be sending us messages from the
4990 lockspace generation before we left. */
4991 if (!ls->ls_generation) {
4992 log_limit(ls, "receive %d from %d ignore old gen",
4993 ms->m_type, nodeid);
4994 return;
4995 }
4996
4997 dlm_add_requestqueue(ls, nodeid, ms);
4998 } else {
4999 dlm_wait_requestqueue(ls);
5000 _receive_message(ls, ms, 0);
5001 }
5002}
5003
5004/* This is called by dlm_recoverd to process messages that were saved on
5005 the requestqueue. */
5006
5007void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
5008 uint32_t saved_seq)
5009{
5010 _receive_message(ls, ms, saved_seq);
5011}
5012
5013/* This is called by the midcomms layer when something is received for
5014 the lockspace. It could be either a MSG (normal message sent as part of
5015 standard locking activity) or an RCOM (recovery message sent as part of
5016 lockspace recovery). */
5017
5018void dlm_receive_buffer(union dlm_packet *p, int nodeid)
5019{
5020 struct dlm_header *hd = &p->header;
5021 struct dlm_ls *ls;
5022 int type = 0;
5023
5024 switch (hd->h_cmd) {
5025 case DLM_MSG:
5026 dlm_message_in(&p->message);
5027 type = p->message.m_type;
5028 break;
5029 case DLM_RCOM:
5030 dlm_rcom_in(&p->rcom);
5031 type = p->rcom.rc_type;
5032 break;
5033 default:
5034 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
5035 return;
5036 }
5037
5038 if (hd->h_nodeid != nodeid) {
5039 log_print("invalid h_nodeid %d from %d lockspace %x",
5040 hd->h_nodeid, nodeid, hd->h_lockspace);
5041 return;
5042 }
5043
5044 ls = dlm_find_lockspace_global(hd->h_lockspace);
5045 if (!ls) {
5046 if (dlm_config.ci_log_debug) {
5047 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
5048 "%u from %d cmd %d type %d\n",
5049 hd->h_lockspace, nodeid, hd->h_cmd, type);
5050 }
5051
5052 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
5053 dlm_send_ls_not_ready(nodeid, &p->rcom);
5054 return;
5055 }
5056
5057 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
5058 be inactive (in this ls) before transitioning to recovery mode */
5059
5060 down_read(&ls->ls_recv_active);
5061 if (hd->h_cmd == DLM_MSG)
5062 dlm_receive_message(ls, &p->message, nodeid);
5063 else
5064 dlm_receive_rcom(ls, &p->rcom, nodeid);
5065 up_read(&ls->ls_recv_active);
5066
5067 dlm_put_lockspace(ls);
5068}
5069
5070static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
5071 struct dlm_message *ms_stub)
5072{
5073 if (middle_conversion(lkb)) {
5074 hold_lkb(lkb);
5075 memset(ms_stub, 0, sizeof(struct dlm_message));
5076 ms_stub->m_flags = DLM_IFL_STUB_MS;
5077 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
5078 ms_stub->m_result = -EINPROGRESS;
5079 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5080 _receive_convert_reply(lkb, ms_stub);
5081
5082 /* Same special case as in receive_rcom_lock_args() */
5083 lkb->lkb_grmode = DLM_LOCK_IV;
5084 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
5085 unhold_lkb(lkb);
5086
5087 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
5088 lkb->lkb_flags |= DLM_IFL_RESEND;
5089 }
5090
5091 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
5092 conversions are async; there's no reply from the remote master */
5093}
5094
5095/* A waiting lkb needs recovery if the master node has failed, or
5096 the master node is changing (only when no directory is used) */
5097
5098static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
5099 int dir_nodeid)
5100{
5101 if (dlm_no_directory(ls))
5102 return 1;
5103
5104 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
5105 return 1;
5106
5107 return 0;
5108}
5109
5110/* Recovery for locks that are waiting for replies from nodes that are now
5111 gone. We can just complete unlocks and cancels by faking a reply from the
5112 dead node. Requests and up-conversions we flag to be resent after
5113 recovery. Down-conversions can just be completed with a fake reply like
5114 unlocks. Conversions between PR and CW need special attention. */
5115
5116void dlm_recover_waiters_pre(struct dlm_ls *ls)
5117{
5118 struct dlm_lkb *lkb, *safe;
5119 struct dlm_message *ms_stub;
5120 int wait_type, stub_unlock_result, stub_cancel_result;
5121 int dir_nodeid;
5122
5123 ms_stub = kmalloc(sizeof(struct dlm_message), GFP_KERNEL);
5124 if (!ms_stub) {
5125 log_error(ls, "dlm_recover_waiters_pre no mem");
5126 return;
5127 }
5128
5129 mutex_lock(&ls->ls_waiters_mutex);
5130
5131 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
5132
5133 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
5134
5135 /* exclude debug messages about unlocks because there can be so
5136 many and they aren't very interesting */
5137
5138 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
5139 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5140 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
5141 lkb->lkb_id,
5142 lkb->lkb_remid,
5143 lkb->lkb_wait_type,
5144 lkb->lkb_resource->res_nodeid,
5145 lkb->lkb_nodeid,
5146 lkb->lkb_wait_nodeid,
5147 dir_nodeid);
5148 }
5149
5150 /* all outstanding lookups, regardless of destination will be
5151 resent after recovery is done */
5152
5153 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
5154 lkb->lkb_flags |= DLM_IFL_RESEND;
5155 continue;
5156 }
5157
5158 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
5159 continue;
5160
5161 wait_type = lkb->lkb_wait_type;
5162 stub_unlock_result = -DLM_EUNLOCK;
5163 stub_cancel_result = -DLM_ECANCEL;
5164
5165 /* Main reply may have been received leaving a zero wait_type,
5166 but a reply for the overlapping op may not have been
5167 received. In that case we need to fake the appropriate
5168 reply for the overlap op. */
5169
5170 if (!wait_type) {
5171 if (is_overlap_cancel(lkb)) {
5172 wait_type = DLM_MSG_CANCEL;
5173 if (lkb->lkb_grmode == DLM_LOCK_IV)
5174 stub_cancel_result = 0;
5175 }
5176 if (is_overlap_unlock(lkb)) {
5177 wait_type = DLM_MSG_UNLOCK;
5178 if (lkb->lkb_grmode == DLM_LOCK_IV)
5179 stub_unlock_result = -ENOENT;
5180 }
5181
5182 log_debug(ls, "rwpre overlap %x %x %d %d %d",
5183 lkb->lkb_id, lkb->lkb_flags, wait_type,
5184 stub_cancel_result, stub_unlock_result);
5185 }
5186
5187 switch (wait_type) {
5188
5189 case DLM_MSG_REQUEST:
5190 lkb->lkb_flags |= DLM_IFL_RESEND;
5191 break;
5192
5193 case DLM_MSG_CONVERT:
5194 recover_convert_waiter(ls, lkb, ms_stub);
5195 break;
5196
5197 case DLM_MSG_UNLOCK:
5198 hold_lkb(lkb);
5199 memset(ms_stub, 0, sizeof(struct dlm_message));
5200 ms_stub->m_flags = DLM_IFL_STUB_MS;
5201 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
5202 ms_stub->m_result = stub_unlock_result;
5203 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5204 _receive_unlock_reply(lkb, ms_stub);
5205 dlm_put_lkb(lkb);
5206 break;
5207
5208 case DLM_MSG_CANCEL:
5209 hold_lkb(lkb);
5210 memset(ms_stub, 0, sizeof(struct dlm_message));
5211 ms_stub->m_flags = DLM_IFL_STUB_MS;
5212 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
5213 ms_stub->m_result = stub_cancel_result;
5214 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5215 _receive_cancel_reply(lkb, ms_stub);
5216 dlm_put_lkb(lkb);
5217 break;
5218
5219 default:
5220 log_error(ls, "invalid lkb wait_type %d %d",
5221 lkb->lkb_wait_type, wait_type);
5222 }
5223 schedule();
5224 }
5225 mutex_unlock(&ls->ls_waiters_mutex);
5226 kfree(ms_stub);
5227}
5228
5229static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
5230{
5231 struct dlm_lkb *lkb;
5232 int found = 0;
5233
5234 mutex_lock(&ls->ls_waiters_mutex);
5235 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
5236 if (lkb->lkb_flags & DLM_IFL_RESEND) {
5237 hold_lkb(lkb);
5238 found = 1;
5239 break;
5240 }
5241 }
5242 mutex_unlock(&ls->ls_waiters_mutex);
5243
5244 if (!found)
5245 lkb = NULL;
5246 return lkb;
5247}
5248
5249/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5250 master or dir-node for r. Processing the lkb may result in it being placed
5251 back on waiters. */
5252
5253/* We do this after normal locking has been enabled and any saved messages
5254 (in requestqueue) have been processed. We should be confident that at
5255 this point we won't get or process a reply to any of these waiting
5256 operations. But, new ops may be coming in on the rsbs/locks here from
5257 userspace or remotely. */
5258
5259/* there may have been an overlap unlock/cancel prior to recovery or after
5260 recovery. if before, the lkb may still have a pos wait_count; if after, the
5261 overlap flag would just have been set and nothing new sent. we can be
5262 confident here than any replies to either the initial op or overlap ops
5263 prior to recovery have been received. */
5264
5265int dlm_recover_waiters_post(struct dlm_ls *ls)
5266{
5267 struct dlm_lkb *lkb;
5268 struct dlm_rsb *r;
5269 int error = 0, mstype, err, oc, ou;
5270
5271 while (1) {
5272 if (dlm_locking_stopped(ls)) {
5273 log_debug(ls, "recover_waiters_post aborted");
5274 error = -EINTR;
5275 break;
5276 }
5277
5278 lkb = find_resend_waiter(ls);
5279 if (!lkb)
5280 break;
5281
5282 r = lkb->lkb_resource;
5283 hold_rsb(r);
5284 lock_rsb(r);
5285
5286 mstype = lkb->lkb_wait_type;
5287 oc = is_overlap_cancel(lkb);
5288 ou = is_overlap_unlock(lkb);
5289 err = 0;
5290
5291 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5292 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5293 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5294 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5295 dlm_dir_nodeid(r), oc, ou);
5296
5297 /* At this point we assume that we won't get a reply to any
5298 previous op or overlap op on this lock. First, do a big
5299 remove_from_waiters() for all previous ops. */
5300
5301 lkb->lkb_flags &= ~DLM_IFL_RESEND;
5302 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
5303 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
5304 lkb->lkb_wait_type = 0;
5305 lkb->lkb_wait_count = 0;
5306 mutex_lock(&ls->ls_waiters_mutex);
5307 list_del_init(&lkb->lkb_wait_reply);
5308 mutex_unlock(&ls->ls_waiters_mutex);
5309 unhold_lkb(lkb); /* for waiters list */
5310
5311 if (oc || ou) {
5312 /* do an unlock or cancel instead of resending */
5313 switch (mstype) {
5314 case DLM_MSG_LOOKUP:
5315 case DLM_MSG_REQUEST:
5316 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5317 -DLM_ECANCEL);
5318 unhold_lkb(lkb); /* undoes create_lkb() */
5319 break;
5320 case DLM_MSG_CONVERT:
5321 if (oc) {
5322 queue_cast(r, lkb, -DLM_ECANCEL);
5323 } else {
5324 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5325 _unlock_lock(r, lkb);
5326 }
5327 break;
5328 default:
5329 err = 1;
5330 }
5331 } else {
5332 switch (mstype) {
5333 case DLM_MSG_LOOKUP:
5334 case DLM_MSG_REQUEST:
5335 _request_lock(r, lkb);
5336 if (is_master(r))
5337 confirm_master(r, 0);
5338 break;
5339 case DLM_MSG_CONVERT:
5340 _convert_lock(r, lkb);
5341 break;
5342 default:
5343 err = 1;
5344 }
5345 }
5346
5347 if (err) {
5348 log_error(ls, "waiter %x msg %d r_nodeid %d "
5349 "dir_nodeid %d overlap %d %d",
5350 lkb->lkb_id, mstype, r->res_nodeid,
5351 dlm_dir_nodeid(r), oc, ou);
5352 }
5353 unlock_rsb(r);
5354 put_rsb(r);
5355 dlm_put_lkb(lkb);
5356 }
5357
5358 return error;
5359}
5360
5361static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5362 struct list_head *list)
5363{
5364 struct dlm_lkb *lkb, *safe;
5365
5366 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5367 if (!is_master_copy(lkb))
5368 continue;
5369
5370 /* don't purge lkbs we've added in recover_master_copy for
5371 the current recovery seq */
5372
5373 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5374 continue;
5375
5376 del_lkb(r, lkb);
5377
5378 /* this put should free the lkb */
5379 if (!dlm_put_lkb(lkb))
5380 log_error(ls, "purged mstcpy lkb not released");
5381 }
5382}
5383
5384void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
5385{
5386 struct dlm_ls *ls = r->res_ls;
5387
5388 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5389 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5390 purge_mstcpy_list(ls, r, &r->res_waitqueue);
5391}
5392
5393static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5394 struct list_head *list,
5395 int nodeid_gone, unsigned int *count)
5396{
5397 struct dlm_lkb *lkb, *safe;
5398
5399 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5400 if (!is_master_copy(lkb))
5401 continue;
5402
5403 if ((lkb->lkb_nodeid == nodeid_gone) ||
5404 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5405
5406 /* tell recover_lvb to invalidate the lvb
5407 because a node holding EX/PW failed */
5408 if ((lkb->lkb_exflags & DLM_LKF_VALBLK) &&
5409 (lkb->lkb_grmode >= DLM_LOCK_PW)) {
5410 rsb_set_flag(r, RSB_RECOVER_LVB_INVAL);
5411 }
5412
5413 del_lkb(r, lkb);
5414
5415 /* this put should free the lkb */
5416 if (!dlm_put_lkb(lkb))
5417 log_error(ls, "purged dead lkb not released");
5418
5419 rsb_set_flag(r, RSB_RECOVER_GRANT);
5420
5421 (*count)++;
5422 }
5423 }
5424}
5425
5426/* Get rid of locks held by nodes that are gone. */
5427
5428void dlm_recover_purge(struct dlm_ls *ls)
5429{
5430 struct dlm_rsb *r;
5431 struct dlm_member *memb;
5432 int nodes_count = 0;
5433 int nodeid_gone = 0;
5434 unsigned int lkb_count = 0;
5435
5436 /* cache one removed nodeid to optimize the common
5437 case of a single node removed */
5438
5439 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5440 nodes_count++;
5441 nodeid_gone = memb->nodeid;
5442 }
5443
5444 if (!nodes_count)
5445 return;
5446
5447 down_write(&ls->ls_root_sem);
5448 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5449 hold_rsb(r);
5450 lock_rsb(r);
5451 if (is_master(r)) {
5452 purge_dead_list(ls, r, &r->res_grantqueue,
5453 nodeid_gone, &lkb_count);
5454 purge_dead_list(ls, r, &r->res_convertqueue,
5455 nodeid_gone, &lkb_count);
5456 purge_dead_list(ls, r, &r->res_waitqueue,
5457 nodeid_gone, &lkb_count);
5458 }
5459 unlock_rsb(r);
5460 unhold_rsb(r);
5461 cond_resched();
5462 }
5463 up_write(&ls->ls_root_sem);
5464
5465 if (lkb_count)
5466 log_rinfo(ls, "dlm_recover_purge %u locks for %u nodes",
5467 lkb_count, nodes_count);
5468}
5469
5470static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
5471{
5472 struct rb_node *n;
5473 struct dlm_rsb *r;
5474
5475 spin_lock(&ls->ls_rsbtbl[bucket].lock);
5476 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5477 r = rb_entry(n, struct dlm_rsb, res_hashnode);
5478
5479 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5480 continue;
5481 if (!is_master(r)) {
5482 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5483 continue;
5484 }
5485 hold_rsb(r);
5486 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5487 return r;
5488 }
5489 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5490 return NULL;
5491}
5492
5493/*
5494 * Attempt to grant locks on resources that we are the master of.
5495 * Locks may have become grantable during recovery because locks
5496 * from departed nodes have been purged (or not rebuilt), allowing
5497 * previously blocked locks to now be granted. The subset of rsb's
5498 * we are interested in are those with lkb's on either the convert or
5499 * waiting queues.
5500 *
5501 * Simplest would be to go through each master rsb and check for non-empty
5502 * convert or waiting queues, and attempt to grant on those rsbs.
5503 * Checking the queues requires lock_rsb, though, for which we'd need
5504 * to release the rsbtbl lock. This would make iterating through all
5505 * rsb's very inefficient. So, we rely on earlier recovery routines
5506 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5507 * locks for.
5508 */
5509
5510void dlm_recover_grant(struct dlm_ls *ls)
5511{
5512 struct dlm_rsb *r;
5513 int bucket = 0;
5514 unsigned int count = 0;
5515 unsigned int rsb_count = 0;
5516 unsigned int lkb_count = 0;
5517
5518 while (1) {
5519 r = find_grant_rsb(ls, bucket);
5520 if (!r) {
5521 if (bucket == ls->ls_rsbtbl_size - 1)
5522 break;
5523 bucket++;
5524 continue;
5525 }
5526 rsb_count++;
5527 count = 0;
5528 lock_rsb(r);
5529 /* the RECOVER_GRANT flag is checked in the grant path */
5530 grant_pending_locks(r, &count);
5531 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5532 lkb_count += count;
5533 confirm_master(r, 0);
5534 unlock_rsb(r);
5535 put_rsb(r);
5536 cond_resched();
5537 }
5538
5539 if (lkb_count)
5540 log_rinfo(ls, "dlm_recover_grant %u locks on %u resources",
5541 lkb_count, rsb_count);
5542}
5543
5544static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5545 uint32_t remid)
5546{
5547 struct dlm_lkb *lkb;
5548
5549 list_for_each_entry(lkb, head, lkb_statequeue) {
5550 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5551 return lkb;
5552 }
5553 return NULL;
5554}
5555
5556static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5557 uint32_t remid)
5558{
5559 struct dlm_lkb *lkb;
5560
5561 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5562 if (lkb)
5563 return lkb;
5564 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5565 if (lkb)
5566 return lkb;
5567 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5568 if (lkb)
5569 return lkb;
5570 return NULL;
5571}
5572
5573/* needs at least dlm_rcom + rcom_lock */
5574static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5575 struct dlm_rsb *r, struct dlm_rcom *rc)
5576{
5577 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5578
5579 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
5580 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5581 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5582 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5583 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
5584 lkb->lkb_flags |= DLM_IFL_MSTCPY;
5585 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
5586 lkb->lkb_rqmode = rl->rl_rqmode;
5587 lkb->lkb_grmode = rl->rl_grmode;
5588 /* don't set lkb_status because add_lkb wants to itself */
5589
5590 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5591 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
5592
5593 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
5594 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
5595 sizeof(struct rcom_lock);
5596 if (lvblen > ls->ls_lvblen)
5597 return -EINVAL;
5598 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
5599 if (!lkb->lkb_lvbptr)
5600 return -ENOMEM;
5601 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5602 }
5603
5604 /* Conversions between PR and CW (middle modes) need special handling.
5605 The real granted mode of these converting locks cannot be determined
5606 until all locks have been rebuilt on the rsb (recover_conversion) */
5607
5608 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5609 middle_conversion(lkb)) {
5610 rl->rl_status = DLM_LKSTS_CONVERT;
5611 lkb->lkb_grmode = DLM_LOCK_IV;
5612 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5613 }
5614
5615 return 0;
5616}
5617
5618/* This lkb may have been recovered in a previous aborted recovery so we need
5619 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5620 If so we just send back a standard reply. If not, we create a new lkb with
5621 the given values and send back our lkid. We send back our lkid by sending
5622 back the rcom_lock struct we got but with the remid field filled in. */
5623
5624/* needs at least dlm_rcom + rcom_lock */
5625int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5626{
5627 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5628 struct dlm_rsb *r;
5629 struct dlm_lkb *lkb;
5630 uint32_t remid = 0;
5631 int from_nodeid = rc->rc_header.h_nodeid;
5632 int error;
5633
5634 if (rl->rl_parent_lkid) {
5635 error = -EOPNOTSUPP;
5636 goto out;
5637 }
5638
5639 remid = le32_to_cpu(rl->rl_lkid);
5640
5641 /* In general we expect the rsb returned to be R_MASTER, but we don't
5642 have to require it. Recovery of masters on one node can overlap
5643 recovery of locks on another node, so one node can send us MSTCPY
5644 locks before we've made ourselves master of this rsb. We can still
5645 add new MSTCPY locks that we receive here without any harm; when
5646 we make ourselves master, dlm_recover_masters() won't touch the
5647 MSTCPY locks we've received early. */
5648
5649 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5650 from_nodeid, R_RECEIVE_RECOVER, &r);
5651 if (error)
5652 goto out;
5653
5654 lock_rsb(r);
5655
5656 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5657 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
5658 from_nodeid, remid);
5659 error = -EBADR;
5660 goto out_unlock;
5661 }
5662
5663 lkb = search_remid(r, from_nodeid, remid);
5664 if (lkb) {
5665 error = -EEXIST;
5666 goto out_remid;
5667 }
5668
5669 error = create_lkb(ls, &lkb);
5670 if (error)
5671 goto out_unlock;
5672
5673 error = receive_rcom_lock_args(ls, lkb, r, rc);
5674 if (error) {
5675 __put_lkb(ls, lkb);
5676 goto out_unlock;
5677 }
5678
5679 attach_lkb(r, lkb);
5680 add_lkb(r, lkb, rl->rl_status);
5681 error = 0;
5682 ls->ls_recover_locks_in++;
5683
5684 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5685 rsb_set_flag(r, RSB_RECOVER_GRANT);
5686
5687 out_remid:
5688 /* this is the new value returned to the lock holder for
5689 saving in its process-copy lkb */
5690 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
5691
5692 lkb->lkb_recover_seq = ls->ls_recover_seq;
5693
5694 out_unlock:
5695 unlock_rsb(r);
5696 put_rsb(r);
5697 out:
5698 if (error && error != -EEXIST)
5699 log_rinfo(ls, "dlm_recover_master_copy remote %d %x error %d",
5700 from_nodeid, remid, error);
5701 rl->rl_result = cpu_to_le32(error);
5702 return error;
5703}
5704
5705/* needs at least dlm_rcom + rcom_lock */
5706int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5707{
5708 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5709 struct dlm_rsb *r;
5710 struct dlm_lkb *lkb;
5711 uint32_t lkid, remid;
5712 int error, result;
5713
5714 lkid = le32_to_cpu(rl->rl_lkid);
5715 remid = le32_to_cpu(rl->rl_remid);
5716 result = le32_to_cpu(rl->rl_result);
5717
5718 error = find_lkb(ls, lkid, &lkb);
5719 if (error) {
5720 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5721 lkid, rc->rc_header.h_nodeid, remid, result);
5722 return error;
5723 }
5724
5725 r = lkb->lkb_resource;
5726 hold_rsb(r);
5727 lock_rsb(r);
5728
5729 if (!is_process_copy(lkb)) {
5730 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5731 lkid, rc->rc_header.h_nodeid, remid, result);
5732 dlm_dump_rsb(r);
5733 unlock_rsb(r);
5734 put_rsb(r);
5735 dlm_put_lkb(lkb);
5736 return -EINVAL;
5737 }
5738
5739 switch (result) {
5740 case -EBADR:
5741 /* There's a chance the new master received our lock before
5742 dlm_recover_master_reply(), this wouldn't happen if we did
5743 a barrier between recover_masters and recover_locks. */
5744
5745 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5746 lkid, rc->rc_header.h_nodeid, remid, result);
5747
5748 dlm_send_rcom_lock(r, lkb);
5749 goto out;
5750 case -EEXIST:
5751 case 0:
5752 lkb->lkb_remid = remid;
5753 break;
5754 default:
5755 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5756 lkid, rc->rc_header.h_nodeid, remid, result);
5757 }
5758
5759 /* an ack for dlm_recover_locks() which waits for replies from
5760 all the locks it sends to new masters */
5761 dlm_recovered_lock(r);
5762 out:
5763 unlock_rsb(r);
5764 put_rsb(r);
5765 dlm_put_lkb(lkb);
5766
5767 return 0;
5768}
5769
5770int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5771 int mode, uint32_t flags, void *name, unsigned int namelen,
5772 unsigned long timeout_cs)
5773{
5774 struct dlm_lkb *lkb;
5775 struct dlm_args args;
5776 int error;
5777
5778 dlm_lock_recovery(ls);
5779
5780 error = create_lkb(ls, &lkb);
5781 if (error) {
5782 kfree(ua);
5783 goto out;
5784 }
5785
5786 if (flags & DLM_LKF_VALBLK) {
5787 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5788 if (!ua->lksb.sb_lvbptr) {
5789 kfree(ua);
5790 __put_lkb(ls, lkb);
5791 error = -ENOMEM;
5792 goto out;
5793 }
5794 }
5795
5796 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
5797 When DLM_IFL_USER is set, the dlm knows that this is a userspace
5798 lock and that lkb_astparam is the dlm_user_args structure. */
5799
5800 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
5801 fake_astfn, ua, fake_bastfn, &args);
5802 lkb->lkb_flags |= DLM_IFL_USER;
5803
5804 if (error) {
5805 __put_lkb(ls, lkb);
5806 goto out;
5807 }
5808
5809 error = request_lock(ls, lkb, name, namelen, &args);
5810
5811 switch (error) {
5812 case 0:
5813 break;
5814 case -EINPROGRESS:
5815 error = 0;
5816 break;
5817 case -EAGAIN:
5818 error = 0;
5819 /* fall through */
5820 default:
5821 __put_lkb(ls, lkb);
5822 goto out;
5823 }
5824
5825 /* add this new lkb to the per-process list of locks */
5826 spin_lock(&ua->proc->locks_spin);
5827 hold_lkb(lkb);
5828 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5829 spin_unlock(&ua->proc->locks_spin);
5830 out:
5831 dlm_unlock_recovery(ls);
5832 return error;
5833}
5834
5835int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5836 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
5837 unsigned long timeout_cs)
5838{
5839 struct dlm_lkb *lkb;
5840 struct dlm_args args;
5841 struct dlm_user_args *ua;
5842 int error;
5843
5844 dlm_lock_recovery(ls);
5845
5846 error = find_lkb(ls, lkid, &lkb);
5847 if (error)
5848 goto out;
5849
5850 /* user can change the params on its lock when it converts it, or
5851 add an lvb that didn't exist before */
5852
5853 ua = lkb->lkb_ua;
5854
5855 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
5856 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5857 if (!ua->lksb.sb_lvbptr) {
5858 error = -ENOMEM;
5859 goto out_put;
5860 }
5861 }
5862 if (lvb_in && ua->lksb.sb_lvbptr)
5863 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5864
5865 ua->xid = ua_tmp->xid;
5866 ua->castparam = ua_tmp->castparam;
5867 ua->castaddr = ua_tmp->castaddr;
5868 ua->bastparam = ua_tmp->bastparam;
5869 ua->bastaddr = ua_tmp->bastaddr;
5870 ua->user_lksb = ua_tmp->user_lksb;
5871
5872 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
5873 fake_astfn, ua, fake_bastfn, &args);
5874 if (error)
5875 goto out_put;
5876
5877 error = convert_lock(ls, lkb, &args);
5878
5879 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
5880 error = 0;
5881 out_put:
5882 dlm_put_lkb(lkb);
5883 out:
5884 dlm_unlock_recovery(ls);
5885 kfree(ua_tmp);
5886 return error;
5887}
5888
5889/*
5890 * The caller asks for an orphan lock on a given resource with a given mode.
5891 * If a matching lock exists, it's moved to the owner's list of locks and
5892 * the lkid is returned.
5893 */
5894
5895int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5896 int mode, uint32_t flags, void *name, unsigned int namelen,
5897 unsigned long timeout_cs, uint32_t *lkid)
5898{
5899 struct dlm_lkb *lkb;
5900 struct dlm_user_args *ua;
5901 int found_other_mode = 0;
5902 int found = 0;
5903 int rv = 0;
5904
5905 mutex_lock(&ls->ls_orphans_mutex);
5906 list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) {
5907 if (lkb->lkb_resource->res_length != namelen)
5908 continue;
5909 if (memcmp(lkb->lkb_resource->res_name, name, namelen))
5910 continue;
5911 if (lkb->lkb_grmode != mode) {
5912 found_other_mode = 1;
5913 continue;
5914 }
5915
5916 found = 1;
5917 list_del_init(&lkb->lkb_ownqueue);
5918 lkb->lkb_flags &= ~DLM_IFL_ORPHAN;
5919 *lkid = lkb->lkb_id;
5920 break;
5921 }
5922 mutex_unlock(&ls->ls_orphans_mutex);
5923
5924 if (!found && found_other_mode) {
5925 rv = -EAGAIN;
5926 goto out;
5927 }
5928
5929 if (!found) {
5930 rv = -ENOENT;
5931 goto out;
5932 }
5933
5934 lkb->lkb_exflags = flags;
5935 lkb->lkb_ownpid = (int) current->pid;
5936
5937 ua = lkb->lkb_ua;
5938
5939 ua->proc = ua_tmp->proc;
5940 ua->xid = ua_tmp->xid;
5941 ua->castparam = ua_tmp->castparam;
5942 ua->castaddr = ua_tmp->castaddr;
5943 ua->bastparam = ua_tmp->bastparam;
5944 ua->bastaddr = ua_tmp->bastaddr;
5945 ua->user_lksb = ua_tmp->user_lksb;
5946
5947 /*
5948 * The lkb reference from the ls_orphans list was not
5949 * removed above, and is now considered the reference
5950 * for the proc locks list.
5951 */
5952
5953 spin_lock(&ua->proc->locks_spin);
5954 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5955 spin_unlock(&ua->proc->locks_spin);
5956 out:
5957 kfree(ua_tmp);
5958 return rv;
5959}
5960
5961int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5962 uint32_t flags, uint32_t lkid, char *lvb_in)
5963{
5964 struct dlm_lkb *lkb;
5965 struct dlm_args args;
5966 struct dlm_user_args *ua;
5967 int error;
5968
5969 dlm_lock_recovery(ls);
5970
5971 error = find_lkb(ls, lkid, &lkb);
5972 if (error)
5973 goto out;
5974
5975 ua = lkb->lkb_ua;
5976
5977 if (lvb_in && ua->lksb.sb_lvbptr)
5978 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5979 if (ua_tmp->castparam)
5980 ua->castparam = ua_tmp->castparam;
5981 ua->user_lksb = ua_tmp->user_lksb;
5982
5983 error = set_unlock_args(flags, ua, &args);
5984 if (error)
5985 goto out_put;
5986
5987 error = unlock_lock(ls, lkb, &args);
5988
5989 if (error == -DLM_EUNLOCK)
5990 error = 0;
5991 /* from validate_unlock_args() */
5992 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5993 error = 0;
5994 if (error)
5995 goto out_put;
5996
5997 spin_lock(&ua->proc->locks_spin);
5998 /* dlm_user_add_cb() may have already taken lkb off the proc list */
5999 if (!list_empty(&lkb->lkb_ownqueue))
6000 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
6001 spin_unlock(&ua->proc->locks_spin);
6002 out_put:
6003 dlm_put_lkb(lkb);
6004 out:
6005 dlm_unlock_recovery(ls);
6006 kfree(ua_tmp);
6007 return error;
6008}
6009
6010int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
6011 uint32_t flags, uint32_t lkid)
6012{
6013 struct dlm_lkb *lkb;
6014 struct dlm_args args;
6015 struct dlm_user_args *ua;
6016 int error;
6017
6018 dlm_lock_recovery(ls);
6019
6020 error = find_lkb(ls, lkid, &lkb);
6021 if (error)
6022 goto out;
6023
6024 ua = lkb->lkb_ua;
6025 if (ua_tmp->castparam)
6026 ua->castparam = ua_tmp->castparam;
6027 ua->user_lksb = ua_tmp->user_lksb;
6028
6029 error = set_unlock_args(flags, ua, &args);
6030 if (error)
6031 goto out_put;
6032
6033 error = cancel_lock(ls, lkb, &args);
6034
6035 if (error == -DLM_ECANCEL)
6036 error = 0;
6037 /* from validate_unlock_args() */
6038 if (error == -EBUSY)
6039 error = 0;
6040 out_put:
6041 dlm_put_lkb(lkb);
6042 out:
6043 dlm_unlock_recovery(ls);
6044 kfree(ua_tmp);
6045 return error;
6046}
6047
6048int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
6049{
6050 struct dlm_lkb *lkb;
6051 struct dlm_args args;
6052 struct dlm_user_args *ua;
6053 struct dlm_rsb *r;
6054 int error;
6055
6056 dlm_lock_recovery(ls);
6057
6058 error = find_lkb(ls, lkid, &lkb);
6059 if (error)
6060 goto out;
6061
6062 ua = lkb->lkb_ua;
6063
6064 error = set_unlock_args(flags, ua, &args);
6065 if (error)
6066 goto out_put;
6067
6068 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
6069
6070 r = lkb->lkb_resource;
6071 hold_rsb(r);
6072 lock_rsb(r);
6073
6074 error = validate_unlock_args(lkb, &args);
6075 if (error)
6076 goto out_r;
6077 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
6078
6079 error = _cancel_lock(r, lkb);
6080 out_r:
6081 unlock_rsb(r);
6082 put_rsb(r);
6083
6084 if (error == -DLM_ECANCEL)
6085 error = 0;
6086 /* from validate_unlock_args() */
6087 if (error == -EBUSY)
6088 error = 0;
6089 out_put:
6090 dlm_put_lkb(lkb);
6091 out:
6092 dlm_unlock_recovery(ls);
6093 return error;
6094}
6095
6096/* lkb's that are removed from the waiters list by revert are just left on the
6097 orphans list with the granted orphan locks, to be freed by purge */
6098
6099static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6100{
6101 struct dlm_args args;
6102 int error;
6103
6104 hold_lkb(lkb); /* reference for the ls_orphans list */
6105 mutex_lock(&ls->ls_orphans_mutex);
6106 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
6107 mutex_unlock(&ls->ls_orphans_mutex);
6108
6109 set_unlock_args(0, lkb->lkb_ua, &args);
6110
6111 error = cancel_lock(ls, lkb, &args);
6112 if (error == -DLM_ECANCEL)
6113 error = 0;
6114 return error;
6115}
6116
6117/* The FORCEUNLOCK flag allows the unlock to go ahead even if the lkb isn't
6118 granted. Regardless of what rsb queue the lock is on, it's removed and
6119 freed. The IVVALBLK flag causes the lvb on the resource to be invalidated
6120 if our lock is PW/EX (it's ignored if our granted mode is smaller.) */
6121
6122static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6123{
6124 struct dlm_args args;
6125 int error;
6126
6127 set_unlock_args(DLM_LKF_FORCEUNLOCK | DLM_LKF_IVVALBLK,
6128 lkb->lkb_ua, &args);
6129
6130 error = unlock_lock(ls, lkb, &args);
6131 if (error == -DLM_EUNLOCK)
6132 error = 0;
6133 return error;
6134}
6135
6136/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
6137 (which does lock_rsb) due to deadlock with receiving a message that does
6138 lock_rsb followed by dlm_user_add_cb() */
6139
6140static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
6141 struct dlm_user_proc *proc)
6142{
6143 struct dlm_lkb *lkb = NULL;
6144
6145 mutex_lock(&ls->ls_clear_proc_locks);
6146 if (list_empty(&proc->locks))
6147 goto out;
6148
6149 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
6150 list_del_init(&lkb->lkb_ownqueue);
6151
6152 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6153 lkb->lkb_flags |= DLM_IFL_ORPHAN;
6154 else
6155 lkb->lkb_flags |= DLM_IFL_DEAD;
6156 out:
6157 mutex_unlock(&ls->ls_clear_proc_locks);
6158 return lkb;
6159}
6160
6161/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
6162 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
6163 which we clear here. */
6164
6165/* proc CLOSING flag is set so no more device_reads should look at proc->asts
6166 list, and no more device_writes should add lkb's to proc->locks list; so we
6167 shouldn't need to take asts_spin or locks_spin here. this assumes that
6168 device reads/writes/closes are serialized -- FIXME: we may need to serialize
6169 them ourself. */
6170
6171void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6172{
6173 struct dlm_lkb *lkb, *safe;
6174
6175 dlm_lock_recovery(ls);
6176
6177 while (1) {
6178 lkb = del_proc_lock(ls, proc);
6179 if (!lkb)
6180 break;
6181 del_timeout(lkb);
6182 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6183 orphan_proc_lock(ls, lkb);
6184 else
6185 unlock_proc_lock(ls, lkb);
6186
6187 /* this removes the reference for the proc->locks list
6188 added by dlm_user_request, it may result in the lkb
6189 being freed */
6190
6191 dlm_put_lkb(lkb);
6192 }
6193
6194 mutex_lock(&ls->ls_clear_proc_locks);
6195
6196 /* in-progress unlocks */
6197 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6198 list_del_init(&lkb->lkb_ownqueue);
6199 lkb->lkb_flags |= DLM_IFL_DEAD;
6200 dlm_put_lkb(lkb);
6201 }
6202
6203 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
6204 memset(&lkb->lkb_callbacks, 0,
6205 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
6206 list_del_init(&lkb->lkb_cb_list);
6207 dlm_put_lkb(lkb);
6208 }
6209
6210 mutex_unlock(&ls->ls_clear_proc_locks);
6211 dlm_unlock_recovery(ls);
6212}
6213
6214static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6215{
6216 struct dlm_lkb *lkb, *safe;
6217
6218 while (1) {
6219 lkb = NULL;
6220 spin_lock(&proc->locks_spin);
6221 if (!list_empty(&proc->locks)) {
6222 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6223 lkb_ownqueue);
6224 list_del_init(&lkb->lkb_ownqueue);
6225 }
6226 spin_unlock(&proc->locks_spin);
6227
6228 if (!lkb)
6229 break;
6230
6231 lkb->lkb_flags |= DLM_IFL_DEAD;
6232 unlock_proc_lock(ls, lkb);
6233 dlm_put_lkb(lkb); /* ref from proc->locks list */
6234 }
6235
6236 spin_lock(&proc->locks_spin);
6237 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6238 list_del_init(&lkb->lkb_ownqueue);
6239 lkb->lkb_flags |= DLM_IFL_DEAD;
6240 dlm_put_lkb(lkb);
6241 }
6242 spin_unlock(&proc->locks_spin);
6243
6244 spin_lock(&proc->asts_spin);
6245 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
6246 memset(&lkb->lkb_callbacks, 0,
6247 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
6248 list_del_init(&lkb->lkb_cb_list);
6249 dlm_put_lkb(lkb);
6250 }
6251 spin_unlock(&proc->asts_spin);
6252}
6253
6254/* pid of 0 means purge all orphans */
6255
6256static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6257{
6258 struct dlm_lkb *lkb, *safe;
6259
6260 mutex_lock(&ls->ls_orphans_mutex);
6261 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6262 if (pid && lkb->lkb_ownpid != pid)
6263 continue;
6264 unlock_proc_lock(ls, lkb);
6265 list_del_init(&lkb->lkb_ownqueue);
6266 dlm_put_lkb(lkb);
6267 }
6268 mutex_unlock(&ls->ls_orphans_mutex);
6269}
6270
6271static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6272{
6273 struct dlm_message *ms;
6274 struct dlm_mhandle *mh;
6275 int error;
6276
6277 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6278 DLM_MSG_PURGE, &ms, &mh);
6279 if (error)
6280 return error;
6281 ms->m_nodeid = nodeid;
6282 ms->m_pid = pid;
6283
6284 return send_message(mh, ms);
6285}
6286
6287int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6288 int nodeid, int pid)
6289{
6290 int error = 0;
6291
6292 if (nodeid && (nodeid != dlm_our_nodeid())) {
6293 error = send_purge(ls, nodeid, pid);
6294 } else {
6295 dlm_lock_recovery(ls);
6296 if (pid == current->pid)
6297 purge_proc_locks(ls, proc);
6298 else
6299 do_purge(ls, nodeid, pid);
6300 dlm_unlock_recovery(ls);
6301 }
6302 return error;
6303}
6304
1// SPDX-License-Identifier: GPL-2.0-only
2/******************************************************************************
3*******************************************************************************
4**
5** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
6**
7**
8*******************************************************************************
9******************************************************************************/
10
11/* Central locking logic has four stages:
12
13 dlm_lock()
14 dlm_unlock()
15
16 request_lock(ls, lkb)
17 convert_lock(ls, lkb)
18 unlock_lock(ls, lkb)
19 cancel_lock(ls, lkb)
20
21 _request_lock(r, lkb)
22 _convert_lock(r, lkb)
23 _unlock_lock(r, lkb)
24 _cancel_lock(r, lkb)
25
26 do_request(r, lkb)
27 do_convert(r, lkb)
28 do_unlock(r, lkb)
29 do_cancel(r, lkb)
30
31 Stage 1 (lock, unlock) is mainly about checking input args and
32 splitting into one of the four main operations:
33
34 dlm_lock = request_lock
35 dlm_lock+CONVERT = convert_lock
36 dlm_unlock = unlock_lock
37 dlm_unlock+CANCEL = cancel_lock
38
39 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
40 provided to the next stage.
41
42 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
43 When remote, it calls send_xxxx(), when local it calls do_xxxx().
44
45 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
46 given rsb and lkb and queues callbacks.
47
48 For remote operations, send_xxxx() results in the corresponding do_xxxx()
49 function being executed on the remote node. The connecting send/receive
50 calls on local (L) and remote (R) nodes:
51
52 L: send_xxxx() -> R: receive_xxxx()
53 R: do_xxxx()
54 L: receive_xxxx_reply() <- R: send_xxxx_reply()
55*/
56#include <linux/types.h>
57#include <linux/rbtree.h>
58#include <linux/slab.h>
59#include "dlm_internal.h"
60#include <linux/dlm_device.h>
61#include "memory.h"
62#include "midcomms.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"
73#include "user.h"
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);
85static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
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);
89static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
90static void del_timeout(struct dlm_lkb *lkb);
91static void toss_rsb(struct kref *kref);
92
93/*
94 * Lock compatibilty matrix - thanks Steve
95 * UN = Unlocked state. Not really a state, used as a flag
96 * PD = Padding. Used to make the matrix a nice power of two in size
97 * Other states are the same as the VMS DLM.
98 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
99 */
100
101static const int __dlm_compat_matrix[8][8] = {
102 /* UN NL CR CW PR PW EX PD */
103 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
104 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
105 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
106 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
107 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
108 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
109 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
110 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
111};
112
113/*
114 * This defines the direction of transfer of LVB data.
115 * Granted mode is the row; requested mode is the column.
116 * Usage: matrix[grmode+1][rqmode+1]
117 * 1 = LVB is returned to the caller
118 * 0 = LVB is written to the resource
119 * -1 = nothing happens to the LVB
120 */
121
122const int dlm_lvb_operations[8][8] = {
123 /* UN NL CR CW PR PW EX PD*/
124 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
125 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
126 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
127 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
128 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
129 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
130 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
131 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
132};
133
134#define modes_compat(gr, rq) \
135 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
136
137int dlm_modes_compat(int mode1, int mode2)
138{
139 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
140}
141
142/*
143 * Compatibility matrix for conversions with QUECVT set.
144 * Granted mode is the row; requested mode is the column.
145 * Usage: matrix[grmode+1][rqmode+1]
146 */
147
148static const int __quecvt_compat_matrix[8][8] = {
149 /* UN NL CR CW PR PW EX PD */
150 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
151 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
152 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
153 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
154 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
155 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
156 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
157 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
158};
159
160void dlm_print_lkb(struct dlm_lkb *lkb)
161{
162 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
163 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
164 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
165 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
166 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
167 (unsigned long long)lkb->lkb_recover_seq);
168}
169
170static void dlm_print_rsb(struct dlm_rsb *r)
171{
172 printk(KERN_ERR "rsb: nodeid %d master %d dir %d flags %lx first %x "
173 "rlc %d name %s\n",
174 r->res_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
175 r->res_flags, r->res_first_lkid, r->res_recover_locks_count,
176 r->res_name);
177}
178
179void dlm_dump_rsb(struct dlm_rsb *r)
180{
181 struct dlm_lkb *lkb;
182
183 dlm_print_rsb(r);
184
185 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
186 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
187 printk(KERN_ERR "rsb lookup list\n");
188 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
189 dlm_print_lkb(lkb);
190 printk(KERN_ERR "rsb grant queue:\n");
191 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
192 dlm_print_lkb(lkb);
193 printk(KERN_ERR "rsb convert queue:\n");
194 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
195 dlm_print_lkb(lkb);
196 printk(KERN_ERR "rsb wait queue:\n");
197 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
198 dlm_print_lkb(lkb);
199}
200
201/* Threads cannot use the lockspace while it's being recovered */
202
203static inline void dlm_lock_recovery(struct dlm_ls *ls)
204{
205 down_read(&ls->ls_in_recovery);
206}
207
208void dlm_unlock_recovery(struct dlm_ls *ls)
209{
210 up_read(&ls->ls_in_recovery);
211}
212
213int dlm_lock_recovery_try(struct dlm_ls *ls)
214{
215 return down_read_trylock(&ls->ls_in_recovery);
216}
217
218static inline int can_be_queued(struct dlm_lkb *lkb)
219{
220 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
221}
222
223static inline int force_blocking_asts(struct dlm_lkb *lkb)
224{
225 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
226}
227
228static inline int is_demoted(struct dlm_lkb *lkb)
229{
230 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
231}
232
233static inline int is_altmode(struct dlm_lkb *lkb)
234{
235 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
236}
237
238static inline int is_granted(struct dlm_lkb *lkb)
239{
240 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
241}
242
243static inline int is_remote(struct dlm_rsb *r)
244{
245 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
246 return !!r->res_nodeid;
247}
248
249static inline int is_process_copy(struct dlm_lkb *lkb)
250{
251 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
252}
253
254static inline int is_master_copy(struct dlm_lkb *lkb)
255{
256 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
257}
258
259static inline int middle_conversion(struct dlm_lkb *lkb)
260{
261 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
262 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
263 return 1;
264 return 0;
265}
266
267static inline int down_conversion(struct dlm_lkb *lkb)
268{
269 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
270}
271
272static inline int is_overlap_unlock(struct dlm_lkb *lkb)
273{
274 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
275}
276
277static inline int is_overlap_cancel(struct dlm_lkb *lkb)
278{
279 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
280}
281
282static inline int is_overlap(struct dlm_lkb *lkb)
283{
284 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
285 DLM_IFL_OVERLAP_CANCEL));
286}
287
288static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
289{
290 if (is_master_copy(lkb))
291 return;
292
293 del_timeout(lkb);
294
295 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
296
297 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
298 timeout caused the cancel then return -ETIMEDOUT */
299 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
300 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
301 rv = -ETIMEDOUT;
302 }
303
304 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
305 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
306 rv = -EDEADLK;
307 }
308
309 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
310}
311
312static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
313{
314 queue_cast(r, lkb,
315 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
316}
317
318static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
319{
320 if (is_master_copy(lkb)) {
321 send_bast(r, lkb, rqmode);
322 } else {
323 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
324 }
325}
326
327/*
328 * Basic operations on rsb's and lkb's
329 */
330
331/* This is only called to add a reference when the code already holds
332 a valid reference to the rsb, so there's no need for locking. */
333
334static inline void hold_rsb(struct dlm_rsb *r)
335{
336 kref_get(&r->res_ref);
337}
338
339void dlm_hold_rsb(struct dlm_rsb *r)
340{
341 hold_rsb(r);
342}
343
344/* When all references to the rsb are gone it's transferred to
345 the tossed list for later disposal. */
346
347static void put_rsb(struct dlm_rsb *r)
348{
349 struct dlm_ls *ls = r->res_ls;
350 uint32_t bucket = r->res_bucket;
351
352 spin_lock(&ls->ls_rsbtbl[bucket].lock);
353 kref_put(&r->res_ref, toss_rsb);
354 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
355}
356
357void dlm_put_rsb(struct dlm_rsb *r)
358{
359 put_rsb(r);
360}
361
362static int pre_rsb_struct(struct dlm_ls *ls)
363{
364 struct dlm_rsb *r1, *r2;
365 int count = 0;
366
367 spin_lock(&ls->ls_new_rsb_spin);
368 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
369 spin_unlock(&ls->ls_new_rsb_spin);
370 return 0;
371 }
372 spin_unlock(&ls->ls_new_rsb_spin);
373
374 r1 = dlm_allocate_rsb(ls);
375 r2 = dlm_allocate_rsb(ls);
376
377 spin_lock(&ls->ls_new_rsb_spin);
378 if (r1) {
379 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
380 ls->ls_new_rsb_count++;
381 }
382 if (r2) {
383 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
384 ls->ls_new_rsb_count++;
385 }
386 count = ls->ls_new_rsb_count;
387 spin_unlock(&ls->ls_new_rsb_spin);
388
389 if (!count)
390 return -ENOMEM;
391 return 0;
392}
393
394/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
395 unlock any spinlocks, go back and call pre_rsb_struct again.
396 Otherwise, take an rsb off the list and return it. */
397
398static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
399 struct dlm_rsb **r_ret)
400{
401 struct dlm_rsb *r;
402 int count;
403
404 spin_lock(&ls->ls_new_rsb_spin);
405 if (list_empty(&ls->ls_new_rsb)) {
406 count = ls->ls_new_rsb_count;
407 spin_unlock(&ls->ls_new_rsb_spin);
408 log_debug(ls, "find_rsb retry %d %d %s",
409 count, dlm_config.ci_new_rsb_count, name);
410 return -EAGAIN;
411 }
412
413 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
414 list_del(&r->res_hashchain);
415 /* Convert the empty list_head to a NULL rb_node for tree usage: */
416 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
417 ls->ls_new_rsb_count--;
418 spin_unlock(&ls->ls_new_rsb_spin);
419
420 r->res_ls = ls;
421 r->res_length = len;
422 memcpy(r->res_name, name, len);
423 mutex_init(&r->res_mutex);
424
425 INIT_LIST_HEAD(&r->res_lookup);
426 INIT_LIST_HEAD(&r->res_grantqueue);
427 INIT_LIST_HEAD(&r->res_convertqueue);
428 INIT_LIST_HEAD(&r->res_waitqueue);
429 INIT_LIST_HEAD(&r->res_root_list);
430 INIT_LIST_HEAD(&r->res_recover_list);
431
432 *r_ret = r;
433 return 0;
434}
435
436static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
437{
438 char maxname[DLM_RESNAME_MAXLEN];
439
440 memset(maxname, 0, DLM_RESNAME_MAXLEN);
441 memcpy(maxname, name, nlen);
442 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
443}
444
445int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
446 struct dlm_rsb **r_ret)
447{
448 struct rb_node *node = tree->rb_node;
449 struct dlm_rsb *r;
450 int rc;
451
452 while (node) {
453 r = rb_entry(node, struct dlm_rsb, res_hashnode);
454 rc = rsb_cmp(r, name, len);
455 if (rc < 0)
456 node = node->rb_left;
457 else if (rc > 0)
458 node = node->rb_right;
459 else
460 goto found;
461 }
462 *r_ret = NULL;
463 return -EBADR;
464
465 found:
466 *r_ret = r;
467 return 0;
468}
469
470static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
471{
472 struct rb_node **newn = &tree->rb_node;
473 struct rb_node *parent = NULL;
474 int rc;
475
476 while (*newn) {
477 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
478 res_hashnode);
479
480 parent = *newn;
481 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
482 if (rc < 0)
483 newn = &parent->rb_left;
484 else if (rc > 0)
485 newn = &parent->rb_right;
486 else {
487 log_print("rsb_insert match");
488 dlm_dump_rsb(rsb);
489 dlm_dump_rsb(cur);
490 return -EEXIST;
491 }
492 }
493
494 rb_link_node(&rsb->res_hashnode, parent, newn);
495 rb_insert_color(&rsb->res_hashnode, tree);
496 return 0;
497}
498
499/*
500 * Find rsb in rsbtbl and potentially create/add one
501 *
502 * Delaying the release of rsb's has a similar benefit to applications keeping
503 * NL locks on an rsb, but without the guarantee that the cached master value
504 * will still be valid when the rsb is reused. Apps aren't always smart enough
505 * to keep NL locks on an rsb that they may lock again shortly; this can lead
506 * to excessive master lookups and removals if we don't delay the release.
507 *
508 * Searching for an rsb means looking through both the normal list and toss
509 * list. When found on the toss list the rsb is moved to the normal list with
510 * ref count of 1; when found on normal list the ref count is incremented.
511 *
512 * rsb's on the keep list are being used locally and refcounted.
513 * rsb's on the toss list are not being used locally, and are not refcounted.
514 *
515 * The toss list rsb's were either
516 * - previously used locally but not any more (were on keep list, then
517 * moved to toss list when last refcount dropped)
518 * - created and put on toss list as a directory record for a lookup
519 * (we are the dir node for the res, but are not using the res right now,
520 * but some other node is)
521 *
522 * The purpose of find_rsb() is to return a refcounted rsb for local use.
523 * So, if the given rsb is on the toss list, it is moved to the keep list
524 * before being returned.
525 *
526 * toss_rsb() happens when all local usage of the rsb is done, i.e. no
527 * more refcounts exist, so the rsb is moved from the keep list to the
528 * toss list.
529 *
530 * rsb's on both keep and toss lists are used for doing a name to master
531 * lookups. rsb's that are in use locally (and being refcounted) are on
532 * the keep list, rsb's that are not in use locally (not refcounted) and
533 * only exist for name/master lookups are on the toss list.
534 *
535 * rsb's on the toss list who's dir_nodeid is not local can have stale
536 * name/master mappings. So, remote requests on such rsb's can potentially
537 * return with an error, which means the mapping is stale and needs to
538 * be updated with a new lookup. (The idea behind MASTER UNCERTAIN and
539 * first_lkid is to keep only a single outstanding request on an rsb
540 * while that rsb has a potentially stale master.)
541 */
542
543static int find_rsb_dir(struct dlm_ls *ls, char *name, int len,
544 uint32_t hash, uint32_t b,
545 int dir_nodeid, int from_nodeid,
546 unsigned int flags, struct dlm_rsb **r_ret)
547{
548 struct dlm_rsb *r = NULL;
549 int our_nodeid = dlm_our_nodeid();
550 int from_local = 0;
551 int from_other = 0;
552 int from_dir = 0;
553 int create = 0;
554 int error;
555
556 if (flags & R_RECEIVE_REQUEST) {
557 if (from_nodeid == dir_nodeid)
558 from_dir = 1;
559 else
560 from_other = 1;
561 } else if (flags & R_REQUEST) {
562 from_local = 1;
563 }
564
565 /*
566 * flags & R_RECEIVE_RECOVER is from dlm_recover_master_copy, so
567 * from_nodeid has sent us a lock in dlm_recover_locks, believing
568 * we're the new master. Our local recovery may not have set
569 * res_master_nodeid to our_nodeid yet, so allow either. Don't
570 * create the rsb; dlm_recover_process_copy() will handle EBADR
571 * by resending.
572 *
573 * If someone sends us a request, we are the dir node, and we do
574 * not find the rsb anywhere, then recreate it. This happens if
575 * someone sends us a request after we have removed/freed an rsb
576 * from our toss list. (They sent a request instead of lookup
577 * because they are using an rsb from their toss list.)
578 */
579
580 if (from_local || from_dir ||
581 (from_other && (dir_nodeid == our_nodeid))) {
582 create = 1;
583 }
584
585 retry:
586 if (create) {
587 error = pre_rsb_struct(ls);
588 if (error < 0)
589 goto out;
590 }
591
592 spin_lock(&ls->ls_rsbtbl[b].lock);
593
594 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
595 if (error)
596 goto do_toss;
597
598 /*
599 * rsb is active, so we can't check master_nodeid without lock_rsb.
600 */
601
602 kref_get(&r->res_ref);
603 error = 0;
604 goto out_unlock;
605
606
607 do_toss:
608 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
609 if (error)
610 goto do_new;
611
612 /*
613 * rsb found inactive (master_nodeid may be out of date unless
614 * we are the dir_nodeid or were the master) No other thread
615 * is using this rsb because it's on the toss list, so we can
616 * look at or update res_master_nodeid without lock_rsb.
617 */
618
619 if ((r->res_master_nodeid != our_nodeid) && from_other) {
620 /* our rsb was not master, and another node (not the dir node)
621 has sent us a request */
622 log_debug(ls, "find_rsb toss from_other %d master %d dir %d %s",
623 from_nodeid, r->res_master_nodeid, dir_nodeid,
624 r->res_name);
625 error = -ENOTBLK;
626 goto out_unlock;
627 }
628
629 if ((r->res_master_nodeid != our_nodeid) && from_dir) {
630 /* don't think this should ever happen */
631 log_error(ls, "find_rsb toss from_dir %d master %d",
632 from_nodeid, r->res_master_nodeid);
633 dlm_print_rsb(r);
634 /* fix it and go on */
635 r->res_master_nodeid = our_nodeid;
636 r->res_nodeid = 0;
637 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
638 r->res_first_lkid = 0;
639 }
640
641 if (from_local && (r->res_master_nodeid != our_nodeid)) {
642 /* Because we have held no locks on this rsb,
643 res_master_nodeid could have become stale. */
644 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
645 r->res_first_lkid = 0;
646 }
647
648 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
649 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
650 goto out_unlock;
651
652
653 do_new:
654 /*
655 * rsb not found
656 */
657
658 if (error == -EBADR && !create)
659 goto out_unlock;
660
661 error = get_rsb_struct(ls, name, len, &r);
662 if (error == -EAGAIN) {
663 spin_unlock(&ls->ls_rsbtbl[b].lock);
664 goto retry;
665 }
666 if (error)
667 goto out_unlock;
668
669 r->res_hash = hash;
670 r->res_bucket = b;
671 r->res_dir_nodeid = dir_nodeid;
672 kref_init(&r->res_ref);
673
674 if (from_dir) {
675 /* want to see how often this happens */
676 log_debug(ls, "find_rsb new from_dir %d recreate %s",
677 from_nodeid, r->res_name);
678 r->res_master_nodeid = our_nodeid;
679 r->res_nodeid = 0;
680 goto out_add;
681 }
682
683 if (from_other && (dir_nodeid != our_nodeid)) {
684 /* should never happen */
685 log_error(ls, "find_rsb new from_other %d dir %d our %d %s",
686 from_nodeid, dir_nodeid, our_nodeid, r->res_name);
687 dlm_free_rsb(r);
688 r = NULL;
689 error = -ENOTBLK;
690 goto out_unlock;
691 }
692
693 if (from_other) {
694 log_debug(ls, "find_rsb new from_other %d dir %d %s",
695 from_nodeid, dir_nodeid, r->res_name);
696 }
697
698 if (dir_nodeid == our_nodeid) {
699 /* When we are the dir nodeid, we can set the master
700 node immediately */
701 r->res_master_nodeid = our_nodeid;
702 r->res_nodeid = 0;
703 } else {
704 /* set_master will send_lookup to dir_nodeid */
705 r->res_master_nodeid = 0;
706 r->res_nodeid = -1;
707 }
708
709 out_add:
710 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
711 out_unlock:
712 spin_unlock(&ls->ls_rsbtbl[b].lock);
713 out:
714 *r_ret = r;
715 return error;
716}
717
718/* During recovery, other nodes can send us new MSTCPY locks (from
719 dlm_recover_locks) before we've made ourself master (in
720 dlm_recover_masters). */
721
722static int find_rsb_nodir(struct dlm_ls *ls, char *name, int len,
723 uint32_t hash, uint32_t b,
724 int dir_nodeid, int from_nodeid,
725 unsigned int flags, struct dlm_rsb **r_ret)
726{
727 struct dlm_rsb *r = NULL;
728 int our_nodeid = dlm_our_nodeid();
729 int recover = (flags & R_RECEIVE_RECOVER);
730 int error;
731
732 retry:
733 error = pre_rsb_struct(ls);
734 if (error < 0)
735 goto out;
736
737 spin_lock(&ls->ls_rsbtbl[b].lock);
738
739 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
740 if (error)
741 goto do_toss;
742
743 /*
744 * rsb is active, so we can't check master_nodeid without lock_rsb.
745 */
746
747 kref_get(&r->res_ref);
748 goto out_unlock;
749
750
751 do_toss:
752 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
753 if (error)
754 goto do_new;
755
756 /*
757 * rsb found inactive. No other thread is using this rsb because
758 * it's on the toss list, so we can look at or update
759 * res_master_nodeid without lock_rsb.
760 */
761
762 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
763 /* our rsb is not master, and another node has sent us a
764 request; this should never happen */
765 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
766 from_nodeid, r->res_master_nodeid, dir_nodeid);
767 dlm_print_rsb(r);
768 error = -ENOTBLK;
769 goto out_unlock;
770 }
771
772 if (!recover && (r->res_master_nodeid != our_nodeid) &&
773 (dir_nodeid == our_nodeid)) {
774 /* our rsb is not master, and we are dir; may as well fix it;
775 this should never happen */
776 log_error(ls, "find_rsb toss our %d master %d dir %d",
777 our_nodeid, r->res_master_nodeid, dir_nodeid);
778 dlm_print_rsb(r);
779 r->res_master_nodeid = our_nodeid;
780 r->res_nodeid = 0;
781 }
782
783 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
784 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
785 goto out_unlock;
786
787
788 do_new:
789 /*
790 * rsb not found
791 */
792
793 error = get_rsb_struct(ls, name, len, &r);
794 if (error == -EAGAIN) {
795 spin_unlock(&ls->ls_rsbtbl[b].lock);
796 goto retry;
797 }
798 if (error)
799 goto out_unlock;
800
801 r->res_hash = hash;
802 r->res_bucket = b;
803 r->res_dir_nodeid = dir_nodeid;
804 r->res_master_nodeid = dir_nodeid;
805 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
806 kref_init(&r->res_ref);
807
808 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
809 out_unlock:
810 spin_unlock(&ls->ls_rsbtbl[b].lock);
811 out:
812 *r_ret = r;
813 return error;
814}
815
816static int find_rsb(struct dlm_ls *ls, char *name, int len, int from_nodeid,
817 unsigned int flags, struct dlm_rsb **r_ret)
818{
819 uint32_t hash, b;
820 int dir_nodeid;
821
822 if (len > DLM_RESNAME_MAXLEN)
823 return -EINVAL;
824
825 hash = jhash(name, len, 0);
826 b = hash & (ls->ls_rsbtbl_size - 1);
827
828 dir_nodeid = dlm_hash2nodeid(ls, hash);
829
830 if (dlm_no_directory(ls))
831 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
832 from_nodeid, flags, r_ret);
833 else
834 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
835 from_nodeid, flags, r_ret);
836}
837
838/* we have received a request and found that res_master_nodeid != our_nodeid,
839 so we need to return an error or make ourself the master */
840
841static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
842 int from_nodeid)
843{
844 if (dlm_no_directory(ls)) {
845 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
846 from_nodeid, r->res_master_nodeid,
847 r->res_dir_nodeid);
848 dlm_print_rsb(r);
849 return -ENOTBLK;
850 }
851
852 if (from_nodeid != r->res_dir_nodeid) {
853 /* our rsb is not master, and another node (not the dir node)
854 has sent us a request. this is much more common when our
855 master_nodeid is zero, so limit debug to non-zero. */
856
857 if (r->res_master_nodeid) {
858 log_debug(ls, "validate master from_other %d master %d "
859 "dir %d first %x %s", from_nodeid,
860 r->res_master_nodeid, r->res_dir_nodeid,
861 r->res_first_lkid, r->res_name);
862 }
863 return -ENOTBLK;
864 } else {
865 /* our rsb is not master, but the dir nodeid has sent us a
866 request; this could happen with master 0 / res_nodeid -1 */
867
868 if (r->res_master_nodeid) {
869 log_error(ls, "validate master from_dir %d master %d "
870 "first %x %s",
871 from_nodeid, r->res_master_nodeid,
872 r->res_first_lkid, r->res_name);
873 }
874
875 r->res_master_nodeid = dlm_our_nodeid();
876 r->res_nodeid = 0;
877 return 0;
878 }
879}
880
881/*
882 * We're the dir node for this res and another node wants to know the
883 * master nodeid. During normal operation (non recovery) this is only
884 * called from receive_lookup(); master lookups when the local node is
885 * the dir node are done by find_rsb().
886 *
887 * normal operation, we are the dir node for a resource
888 * . _request_lock
889 * . set_master
890 * . send_lookup
891 * . receive_lookup
892 * . dlm_master_lookup flags 0
893 *
894 * recover directory, we are rebuilding dir for all resources
895 * . dlm_recover_directory
896 * . dlm_rcom_names
897 * remote node sends back the rsb names it is master of and we are dir of
898 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
899 * we either create new rsb setting remote node as master, or find existing
900 * rsb and set master to be the remote node.
901 *
902 * recover masters, we are finding the new master for resources
903 * . dlm_recover_masters
904 * . recover_master
905 * . dlm_send_rcom_lookup
906 * . receive_rcom_lookup
907 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
908 */
909
910int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, char *name, int len,
911 unsigned int flags, int *r_nodeid, int *result)
912{
913 struct dlm_rsb *r = NULL;
914 uint32_t hash, b;
915 int from_master = (flags & DLM_LU_RECOVER_DIR);
916 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
917 int our_nodeid = dlm_our_nodeid();
918 int dir_nodeid, error, toss_list = 0;
919
920 if (len > DLM_RESNAME_MAXLEN)
921 return -EINVAL;
922
923 if (from_nodeid == our_nodeid) {
924 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
925 our_nodeid, flags);
926 return -EINVAL;
927 }
928
929 hash = jhash(name, len, 0);
930 b = hash & (ls->ls_rsbtbl_size - 1);
931
932 dir_nodeid = dlm_hash2nodeid(ls, hash);
933 if (dir_nodeid != our_nodeid) {
934 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
935 from_nodeid, dir_nodeid, our_nodeid, hash,
936 ls->ls_num_nodes);
937 *r_nodeid = -1;
938 return -EINVAL;
939 }
940
941 retry:
942 error = pre_rsb_struct(ls);
943 if (error < 0)
944 return error;
945
946 spin_lock(&ls->ls_rsbtbl[b].lock);
947 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
948 if (!error) {
949 /* because the rsb is active, we need to lock_rsb before
950 checking/changing re_master_nodeid */
951
952 hold_rsb(r);
953 spin_unlock(&ls->ls_rsbtbl[b].lock);
954 lock_rsb(r);
955 goto found;
956 }
957
958 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
959 if (error)
960 goto not_found;
961
962 /* because the rsb is inactive (on toss list), it's not refcounted
963 and lock_rsb is not used, but is protected by the rsbtbl lock */
964
965 toss_list = 1;
966 found:
967 if (r->res_dir_nodeid != our_nodeid) {
968 /* should not happen, but may as well fix it and carry on */
969 log_error(ls, "dlm_master_lookup res_dir %d our %d %s",
970 r->res_dir_nodeid, our_nodeid, r->res_name);
971 r->res_dir_nodeid = our_nodeid;
972 }
973
974 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
975 /* Recovery uses this function to set a new master when
976 the previous master failed. Setting NEW_MASTER will
977 force dlm_recover_masters to call recover_master on this
978 rsb even though the res_nodeid is no longer removed. */
979
980 r->res_master_nodeid = from_nodeid;
981 r->res_nodeid = from_nodeid;
982 rsb_set_flag(r, RSB_NEW_MASTER);
983
984 if (toss_list) {
985 /* I don't think we should ever find it on toss list. */
986 log_error(ls, "dlm_master_lookup fix_master on toss");
987 dlm_dump_rsb(r);
988 }
989 }
990
991 if (from_master && (r->res_master_nodeid != from_nodeid)) {
992 /* this will happen if from_nodeid became master during
993 a previous recovery cycle, and we aborted the previous
994 cycle before recovering this master value */
995
996 log_limit(ls, "dlm_master_lookup from_master %d "
997 "master_nodeid %d res_nodeid %d first %x %s",
998 from_nodeid, r->res_master_nodeid, r->res_nodeid,
999 r->res_first_lkid, r->res_name);
1000
1001 if (r->res_master_nodeid == our_nodeid) {
1002 log_error(ls, "from_master %d our_master", from_nodeid);
1003 dlm_dump_rsb(r);
1004 goto out_found;
1005 }
1006
1007 r->res_master_nodeid = from_nodeid;
1008 r->res_nodeid = from_nodeid;
1009 rsb_set_flag(r, RSB_NEW_MASTER);
1010 }
1011
1012 if (!r->res_master_nodeid) {
1013 /* this will happen if recovery happens while we're looking
1014 up the master for this rsb */
1015
1016 log_debug(ls, "dlm_master_lookup master 0 to %d first %x %s",
1017 from_nodeid, r->res_first_lkid, r->res_name);
1018 r->res_master_nodeid = from_nodeid;
1019 r->res_nodeid = from_nodeid;
1020 }
1021
1022 if (!from_master && !fix_master &&
1023 (r->res_master_nodeid == from_nodeid)) {
1024 /* this can happen when the master sends remove, the dir node
1025 finds the rsb on the keep list and ignores the remove,
1026 and the former master sends a lookup */
1027
1028 log_limit(ls, "dlm_master_lookup from master %d flags %x "
1029 "first %x %s", from_nodeid, flags,
1030 r->res_first_lkid, r->res_name);
1031 }
1032
1033 out_found:
1034 *r_nodeid = r->res_master_nodeid;
1035 if (result)
1036 *result = DLM_LU_MATCH;
1037
1038 if (toss_list) {
1039 r->res_toss_time = jiffies;
1040 /* the rsb was inactive (on toss list) */
1041 spin_unlock(&ls->ls_rsbtbl[b].lock);
1042 } else {
1043 /* the rsb was active */
1044 unlock_rsb(r);
1045 put_rsb(r);
1046 }
1047 return 0;
1048
1049 not_found:
1050 error = get_rsb_struct(ls, name, len, &r);
1051 if (error == -EAGAIN) {
1052 spin_unlock(&ls->ls_rsbtbl[b].lock);
1053 goto retry;
1054 }
1055 if (error)
1056 goto out_unlock;
1057
1058 r->res_hash = hash;
1059 r->res_bucket = b;
1060 r->res_dir_nodeid = our_nodeid;
1061 r->res_master_nodeid = from_nodeid;
1062 r->res_nodeid = from_nodeid;
1063 kref_init(&r->res_ref);
1064 r->res_toss_time = jiffies;
1065
1066 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1067 if (error) {
1068 /* should never happen */
1069 dlm_free_rsb(r);
1070 spin_unlock(&ls->ls_rsbtbl[b].lock);
1071 goto retry;
1072 }
1073
1074 if (result)
1075 *result = DLM_LU_ADD;
1076 *r_nodeid = from_nodeid;
1077 error = 0;
1078 out_unlock:
1079 spin_unlock(&ls->ls_rsbtbl[b].lock);
1080 return error;
1081}
1082
1083static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1084{
1085 struct rb_node *n;
1086 struct dlm_rsb *r;
1087 int i;
1088
1089 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1090 spin_lock(&ls->ls_rsbtbl[i].lock);
1091 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1092 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1093 if (r->res_hash == hash)
1094 dlm_dump_rsb(r);
1095 }
1096 spin_unlock(&ls->ls_rsbtbl[i].lock);
1097 }
1098}
1099
1100void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len)
1101{
1102 struct dlm_rsb *r = NULL;
1103 uint32_t hash, b;
1104 int error;
1105
1106 hash = jhash(name, len, 0);
1107 b = hash & (ls->ls_rsbtbl_size - 1);
1108
1109 spin_lock(&ls->ls_rsbtbl[b].lock);
1110 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1111 if (!error)
1112 goto out_dump;
1113
1114 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1115 if (error)
1116 goto out;
1117 out_dump:
1118 dlm_dump_rsb(r);
1119 out:
1120 spin_unlock(&ls->ls_rsbtbl[b].lock);
1121}
1122
1123static void toss_rsb(struct kref *kref)
1124{
1125 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1126 struct dlm_ls *ls = r->res_ls;
1127
1128 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1129 kref_init(&r->res_ref);
1130 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1131 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
1132 r->res_toss_time = jiffies;
1133 ls->ls_rsbtbl[r->res_bucket].flags |= DLM_RTF_SHRINK;
1134 if (r->res_lvbptr) {
1135 dlm_free_lvb(r->res_lvbptr);
1136 r->res_lvbptr = NULL;
1137 }
1138}
1139
1140/* See comment for unhold_lkb */
1141
1142static void unhold_rsb(struct dlm_rsb *r)
1143{
1144 int rv;
1145 rv = kref_put(&r->res_ref, toss_rsb);
1146 DLM_ASSERT(!rv, dlm_dump_rsb(r););
1147}
1148
1149static void kill_rsb(struct kref *kref)
1150{
1151 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1152
1153 /* All work is done after the return from kref_put() so we
1154 can release the write_lock before the remove and free. */
1155
1156 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1157 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1158 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1159 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1160 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1161 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
1162}
1163
1164/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1165 The rsb must exist as long as any lkb's for it do. */
1166
1167static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1168{
1169 hold_rsb(r);
1170 lkb->lkb_resource = r;
1171}
1172
1173static void detach_lkb(struct dlm_lkb *lkb)
1174{
1175 if (lkb->lkb_resource) {
1176 put_rsb(lkb->lkb_resource);
1177 lkb->lkb_resource = NULL;
1178 }
1179}
1180
1181static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1182{
1183 struct dlm_lkb *lkb;
1184 int rv;
1185
1186 lkb = dlm_allocate_lkb(ls);
1187 if (!lkb)
1188 return -ENOMEM;
1189
1190 lkb->lkb_nodeid = -1;
1191 lkb->lkb_grmode = DLM_LOCK_IV;
1192 kref_init(&lkb->lkb_ref);
1193 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
1194 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
1195 INIT_LIST_HEAD(&lkb->lkb_time_list);
1196 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1197 mutex_init(&lkb->lkb_cb_mutex);
1198 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
1199
1200 idr_preload(GFP_NOFS);
1201 spin_lock(&ls->ls_lkbidr_spin);
1202 rv = idr_alloc(&ls->ls_lkbidr, lkb, 1, 0, GFP_NOWAIT);
1203 if (rv >= 0)
1204 lkb->lkb_id = rv;
1205 spin_unlock(&ls->ls_lkbidr_spin);
1206 idr_preload_end();
1207
1208 if (rv < 0) {
1209 log_error(ls, "create_lkb idr error %d", rv);
1210 dlm_free_lkb(lkb);
1211 return rv;
1212 }
1213
1214 *lkb_ret = lkb;
1215 return 0;
1216}
1217
1218static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1219{
1220 struct dlm_lkb *lkb;
1221
1222 spin_lock(&ls->ls_lkbidr_spin);
1223 lkb = idr_find(&ls->ls_lkbidr, lkid);
1224 if (lkb)
1225 kref_get(&lkb->lkb_ref);
1226 spin_unlock(&ls->ls_lkbidr_spin);
1227
1228 *lkb_ret = lkb;
1229 return lkb ? 0 : -ENOENT;
1230}
1231
1232static void kill_lkb(struct kref *kref)
1233{
1234 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1235
1236 /* All work is done after the return from kref_put() so we
1237 can release the write_lock before the detach_lkb */
1238
1239 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1240}
1241
1242/* __put_lkb() is used when an lkb may not have an rsb attached to
1243 it so we need to provide the lockspace explicitly */
1244
1245static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
1246{
1247 uint32_t lkid = lkb->lkb_id;
1248
1249 spin_lock(&ls->ls_lkbidr_spin);
1250 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
1251 idr_remove(&ls->ls_lkbidr, lkid);
1252 spin_unlock(&ls->ls_lkbidr_spin);
1253
1254 detach_lkb(lkb);
1255
1256 /* for local/process lkbs, lvbptr points to caller's lksb */
1257 if (lkb->lkb_lvbptr && is_master_copy(lkb))
1258 dlm_free_lvb(lkb->lkb_lvbptr);
1259 dlm_free_lkb(lkb);
1260 return 1;
1261 } else {
1262 spin_unlock(&ls->ls_lkbidr_spin);
1263 return 0;
1264 }
1265}
1266
1267int dlm_put_lkb(struct dlm_lkb *lkb)
1268{
1269 struct dlm_ls *ls;
1270
1271 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1272 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1273
1274 ls = lkb->lkb_resource->res_ls;
1275 return __put_lkb(ls, lkb);
1276}
1277
1278/* This is only called to add a reference when the code already holds
1279 a valid reference to the lkb, so there's no need for locking. */
1280
1281static inline void hold_lkb(struct dlm_lkb *lkb)
1282{
1283 kref_get(&lkb->lkb_ref);
1284}
1285
1286/* This is called when we need to remove a reference and are certain
1287 it's not the last ref. e.g. del_lkb is always called between a
1288 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1289 put_lkb would work fine, but would involve unnecessary locking */
1290
1291static inline void unhold_lkb(struct dlm_lkb *lkb)
1292{
1293 int rv;
1294 rv = kref_put(&lkb->lkb_ref, kill_lkb);
1295 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
1296}
1297
1298static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1299 int mode)
1300{
1301 struct dlm_lkb *lkb = NULL;
1302
1303 list_for_each_entry(lkb, head, lkb_statequeue)
1304 if (lkb->lkb_rqmode < mode)
1305 break;
1306
1307 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
1308}
1309
1310/* add/remove lkb to rsb's grant/convert/wait queue */
1311
1312static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1313{
1314 kref_get(&lkb->lkb_ref);
1315
1316 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1317
1318 lkb->lkb_timestamp = ktime_get();
1319
1320 lkb->lkb_status = status;
1321
1322 switch (status) {
1323 case DLM_LKSTS_WAITING:
1324 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1325 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1326 else
1327 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1328 break;
1329 case DLM_LKSTS_GRANTED:
1330 /* convention says granted locks kept in order of grmode */
1331 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1332 lkb->lkb_grmode);
1333 break;
1334 case DLM_LKSTS_CONVERT:
1335 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1336 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1337 else
1338 list_add_tail(&lkb->lkb_statequeue,
1339 &r->res_convertqueue);
1340 break;
1341 default:
1342 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1343 }
1344}
1345
1346static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1347{
1348 lkb->lkb_status = 0;
1349 list_del(&lkb->lkb_statequeue);
1350 unhold_lkb(lkb);
1351}
1352
1353static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1354{
1355 hold_lkb(lkb);
1356 del_lkb(r, lkb);
1357 add_lkb(r, lkb, sts);
1358 unhold_lkb(lkb);
1359}
1360
1361static int msg_reply_type(int mstype)
1362{
1363 switch (mstype) {
1364 case DLM_MSG_REQUEST:
1365 return DLM_MSG_REQUEST_REPLY;
1366 case DLM_MSG_CONVERT:
1367 return DLM_MSG_CONVERT_REPLY;
1368 case DLM_MSG_UNLOCK:
1369 return DLM_MSG_UNLOCK_REPLY;
1370 case DLM_MSG_CANCEL:
1371 return DLM_MSG_CANCEL_REPLY;
1372 case DLM_MSG_LOOKUP:
1373 return DLM_MSG_LOOKUP_REPLY;
1374 }
1375 return -1;
1376}
1377
1378static int nodeid_warned(int nodeid, int num_nodes, int *warned)
1379{
1380 int i;
1381
1382 for (i = 0; i < num_nodes; i++) {
1383 if (!warned[i]) {
1384 warned[i] = nodeid;
1385 return 0;
1386 }
1387 if (warned[i] == nodeid)
1388 return 1;
1389 }
1390 return 0;
1391}
1392
1393void dlm_scan_waiters(struct dlm_ls *ls)
1394{
1395 struct dlm_lkb *lkb;
1396 s64 us;
1397 s64 debug_maxus = 0;
1398 u32 debug_scanned = 0;
1399 u32 debug_expired = 0;
1400 int num_nodes = 0;
1401 int *warned = NULL;
1402
1403 if (!dlm_config.ci_waitwarn_us)
1404 return;
1405
1406 mutex_lock(&ls->ls_waiters_mutex);
1407
1408 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1409 if (!lkb->lkb_wait_time)
1410 continue;
1411
1412 debug_scanned++;
1413
1414 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
1415
1416 if (us < dlm_config.ci_waitwarn_us)
1417 continue;
1418
1419 lkb->lkb_wait_time = 0;
1420
1421 debug_expired++;
1422 if (us > debug_maxus)
1423 debug_maxus = us;
1424
1425 if (!num_nodes) {
1426 num_nodes = ls->ls_num_nodes;
1427 warned = kcalloc(num_nodes, sizeof(int), GFP_KERNEL);
1428 }
1429 if (!warned)
1430 continue;
1431 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
1432 continue;
1433
1434 log_error(ls, "waitwarn %x %lld %d us check connection to "
1435 "node %d", lkb->lkb_id, (long long)us,
1436 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
1437 }
1438 mutex_unlock(&ls->ls_waiters_mutex);
1439 kfree(warned);
1440
1441 if (debug_expired)
1442 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
1443 debug_scanned, debug_expired,
1444 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
1445}
1446
1447/* add/remove lkb from global waiters list of lkb's waiting for
1448 a reply from a remote node */
1449
1450static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
1451{
1452 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1453 int error = 0;
1454
1455 mutex_lock(&ls->ls_waiters_mutex);
1456
1457 if (is_overlap_unlock(lkb) ||
1458 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1459 error = -EINVAL;
1460 goto out;
1461 }
1462
1463 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1464 switch (mstype) {
1465 case DLM_MSG_UNLOCK:
1466 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
1467 break;
1468 case DLM_MSG_CANCEL:
1469 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
1470 break;
1471 default:
1472 error = -EBUSY;
1473 goto out;
1474 }
1475 lkb->lkb_wait_count++;
1476 hold_lkb(lkb);
1477
1478 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
1479 lkb->lkb_id, lkb->lkb_wait_type, mstype,
1480 lkb->lkb_wait_count, lkb->lkb_flags);
1481 goto out;
1482 }
1483
1484 DLM_ASSERT(!lkb->lkb_wait_count,
1485 dlm_print_lkb(lkb);
1486 printk("wait_count %d\n", lkb->lkb_wait_count););
1487
1488 lkb->lkb_wait_count++;
1489 lkb->lkb_wait_type = mstype;
1490 lkb->lkb_wait_time = ktime_get();
1491 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
1492 hold_lkb(lkb);
1493 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1494 out:
1495 if (error)
1496 log_error(ls, "addwait error %x %d flags %x %d %d %s",
1497 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1498 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
1499 mutex_unlock(&ls->ls_waiters_mutex);
1500 return error;
1501}
1502
1503/* We clear the RESEND flag because we might be taking an lkb off the waiters
1504 list as part of process_requestqueue (e.g. a lookup that has an optimized
1505 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1506 set RESEND and dlm_recover_waiters_post() */
1507
1508static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1509 struct dlm_message *ms)
1510{
1511 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1512 int overlap_done = 0;
1513
1514 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
1515 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
1516 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1517 overlap_done = 1;
1518 goto out_del;
1519 }
1520
1521 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
1522 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
1523 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1524 overlap_done = 1;
1525 goto out_del;
1526 }
1527
1528 /* Cancel state was preemptively cleared by a successful convert,
1529 see next comment, nothing to do. */
1530
1531 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1532 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1533 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1534 lkb->lkb_id, lkb->lkb_wait_type);
1535 return -1;
1536 }
1537
1538 /* Remove for the convert reply, and premptively remove for the
1539 cancel reply. A convert has been granted while there's still
1540 an outstanding cancel on it (the cancel is moot and the result
1541 in the cancel reply should be 0). We preempt the cancel reply
1542 because the app gets the convert result and then can follow up
1543 with another op, like convert. This subsequent op would see the
1544 lingering state of the cancel and fail with -EBUSY. */
1545
1546 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1547 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1548 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1549 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1550 lkb->lkb_id);
1551 lkb->lkb_wait_type = 0;
1552 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1553 lkb->lkb_wait_count--;
1554 goto out_del;
1555 }
1556
1557 /* N.B. type of reply may not always correspond to type of original
1558 msg due to lookup->request optimization, verify others? */
1559
1560 if (lkb->lkb_wait_type) {
1561 lkb->lkb_wait_type = 0;
1562 goto out_del;
1563 }
1564
1565 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1566 lkb->lkb_id, ms ? ms->m_header.h_nodeid : 0, lkb->lkb_remid,
1567 mstype, lkb->lkb_flags);
1568 return -1;
1569
1570 out_del:
1571 /* the force-unlock/cancel has completed and we haven't recvd a reply
1572 to the op that was in progress prior to the unlock/cancel; we
1573 give up on any reply to the earlier op. FIXME: not sure when/how
1574 this would happen */
1575
1576 if (overlap_done && lkb->lkb_wait_type) {
1577 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
1578 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1579 lkb->lkb_wait_count--;
1580 lkb->lkb_wait_type = 0;
1581 }
1582
1583 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1584
1585 lkb->lkb_flags &= ~DLM_IFL_RESEND;
1586 lkb->lkb_wait_count--;
1587 if (!lkb->lkb_wait_count)
1588 list_del_init(&lkb->lkb_wait_reply);
1589 unhold_lkb(lkb);
1590 return 0;
1591}
1592
1593static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
1594{
1595 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1596 int error;
1597
1598 mutex_lock(&ls->ls_waiters_mutex);
1599 error = _remove_from_waiters(lkb, mstype, NULL);
1600 mutex_unlock(&ls->ls_waiters_mutex);
1601 return error;
1602}
1603
1604/* Handles situations where we might be processing a "fake" or "stub" reply in
1605 which we can't try to take waiters_mutex again. */
1606
1607static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1608{
1609 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1610 int error;
1611
1612 if (ms->m_flags != DLM_IFL_STUB_MS)
1613 mutex_lock(&ls->ls_waiters_mutex);
1614 error = _remove_from_waiters(lkb, ms->m_type, ms);
1615 if (ms->m_flags != DLM_IFL_STUB_MS)
1616 mutex_unlock(&ls->ls_waiters_mutex);
1617 return error;
1618}
1619
1620/* If there's an rsb for the same resource being removed, ensure
1621 that the remove message is sent before the new lookup message.
1622 It should be rare to need a delay here, but if not, then it may
1623 be worthwhile to add a proper wait mechanism rather than a delay. */
1624
1625static void wait_pending_remove(struct dlm_rsb *r)
1626{
1627 struct dlm_ls *ls = r->res_ls;
1628 restart:
1629 spin_lock(&ls->ls_remove_spin);
1630 if (ls->ls_remove_len &&
1631 !rsb_cmp(r, ls->ls_remove_name, ls->ls_remove_len)) {
1632 log_debug(ls, "delay lookup for remove dir %d %s",
1633 r->res_dir_nodeid, r->res_name);
1634 spin_unlock(&ls->ls_remove_spin);
1635 msleep(1);
1636 goto restart;
1637 }
1638 spin_unlock(&ls->ls_remove_spin);
1639}
1640
1641/*
1642 * ls_remove_spin protects ls_remove_name and ls_remove_len which are
1643 * read by other threads in wait_pending_remove. ls_remove_names
1644 * and ls_remove_lens are only used by the scan thread, so they do
1645 * not need protection.
1646 */
1647
1648static void shrink_bucket(struct dlm_ls *ls, int b)
1649{
1650 struct rb_node *n, *next;
1651 struct dlm_rsb *r;
1652 char *name;
1653 int our_nodeid = dlm_our_nodeid();
1654 int remote_count = 0;
1655 int need_shrink = 0;
1656 int i, len, rv;
1657
1658 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
1659
1660 spin_lock(&ls->ls_rsbtbl[b].lock);
1661
1662 if (!(ls->ls_rsbtbl[b].flags & DLM_RTF_SHRINK)) {
1663 spin_unlock(&ls->ls_rsbtbl[b].lock);
1664 return;
1665 }
1666
1667 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) {
1668 next = rb_next(n);
1669 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1670
1671 /* If we're the directory record for this rsb, and
1672 we're not the master of it, then we need to wait
1673 for the master node to send us a dir remove for
1674 before removing the dir record. */
1675
1676 if (!dlm_no_directory(ls) &&
1677 (r->res_master_nodeid != our_nodeid) &&
1678 (dlm_dir_nodeid(r) == our_nodeid)) {
1679 continue;
1680 }
1681
1682 need_shrink = 1;
1683
1684 if (!time_after_eq(jiffies, r->res_toss_time +
1685 dlm_config.ci_toss_secs * HZ)) {
1686 continue;
1687 }
1688
1689 if (!dlm_no_directory(ls) &&
1690 (r->res_master_nodeid == our_nodeid) &&
1691 (dlm_dir_nodeid(r) != our_nodeid)) {
1692
1693 /* We're the master of this rsb but we're not
1694 the directory record, so we need to tell the
1695 dir node to remove the dir record. */
1696
1697 ls->ls_remove_lens[remote_count] = r->res_length;
1698 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1699 DLM_RESNAME_MAXLEN);
1700 remote_count++;
1701
1702 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1703 break;
1704 continue;
1705 }
1706
1707 if (!kref_put(&r->res_ref, kill_rsb)) {
1708 log_error(ls, "tossed rsb in use %s", r->res_name);
1709 continue;
1710 }
1711
1712 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1713 dlm_free_rsb(r);
1714 }
1715
1716 if (need_shrink)
1717 ls->ls_rsbtbl[b].flags |= DLM_RTF_SHRINK;
1718 else
1719 ls->ls_rsbtbl[b].flags &= ~DLM_RTF_SHRINK;
1720 spin_unlock(&ls->ls_rsbtbl[b].lock);
1721
1722 /*
1723 * While searching for rsb's to free, we found some that require
1724 * remote removal. We leave them in place and find them again here
1725 * so there is a very small gap between removing them from the toss
1726 * list and sending the removal. Keeping this gap small is
1727 * important to keep us (the master node) from being out of sync
1728 * with the remote dir node for very long.
1729 *
1730 * From the time the rsb is removed from toss until just after
1731 * send_remove, the rsb name is saved in ls_remove_name. A new
1732 * lookup checks this to ensure that a new lookup message for the
1733 * same resource name is not sent just before the remove message.
1734 */
1735
1736 for (i = 0; i < remote_count; i++) {
1737 name = ls->ls_remove_names[i];
1738 len = ls->ls_remove_lens[i];
1739
1740 spin_lock(&ls->ls_rsbtbl[b].lock);
1741 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1742 if (rv) {
1743 spin_unlock(&ls->ls_rsbtbl[b].lock);
1744 log_debug(ls, "remove_name not toss %s", name);
1745 continue;
1746 }
1747
1748 if (r->res_master_nodeid != our_nodeid) {
1749 spin_unlock(&ls->ls_rsbtbl[b].lock);
1750 log_debug(ls, "remove_name master %d dir %d our %d %s",
1751 r->res_master_nodeid, r->res_dir_nodeid,
1752 our_nodeid, name);
1753 continue;
1754 }
1755
1756 if (r->res_dir_nodeid == our_nodeid) {
1757 /* should never happen */
1758 spin_unlock(&ls->ls_rsbtbl[b].lock);
1759 log_error(ls, "remove_name dir %d master %d our %d %s",
1760 r->res_dir_nodeid, r->res_master_nodeid,
1761 our_nodeid, name);
1762 continue;
1763 }
1764
1765 if (!time_after_eq(jiffies, r->res_toss_time +
1766 dlm_config.ci_toss_secs * HZ)) {
1767 spin_unlock(&ls->ls_rsbtbl[b].lock);
1768 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1769 r->res_toss_time, jiffies, name);
1770 continue;
1771 }
1772
1773 if (!kref_put(&r->res_ref, kill_rsb)) {
1774 spin_unlock(&ls->ls_rsbtbl[b].lock);
1775 log_error(ls, "remove_name in use %s", name);
1776 continue;
1777 }
1778
1779 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1780
1781 /* block lookup of same name until we've sent remove */
1782 spin_lock(&ls->ls_remove_spin);
1783 ls->ls_remove_len = len;
1784 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
1785 spin_unlock(&ls->ls_remove_spin);
1786 spin_unlock(&ls->ls_rsbtbl[b].lock);
1787
1788 send_remove(r);
1789
1790 /* allow lookup of name again */
1791 spin_lock(&ls->ls_remove_spin);
1792 ls->ls_remove_len = 0;
1793 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
1794 spin_unlock(&ls->ls_remove_spin);
1795
1796 dlm_free_rsb(r);
1797 }
1798}
1799
1800void dlm_scan_rsbs(struct dlm_ls *ls)
1801{
1802 int i;
1803
1804 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1805 shrink_bucket(ls, i);
1806 if (dlm_locking_stopped(ls))
1807 break;
1808 cond_resched();
1809 }
1810}
1811
1812static void add_timeout(struct dlm_lkb *lkb)
1813{
1814 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1815
1816 if (is_master_copy(lkb))
1817 return;
1818
1819 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1820 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1821 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1822 goto add_it;
1823 }
1824 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1825 goto add_it;
1826 return;
1827
1828 add_it:
1829 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1830 mutex_lock(&ls->ls_timeout_mutex);
1831 hold_lkb(lkb);
1832 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1833 mutex_unlock(&ls->ls_timeout_mutex);
1834}
1835
1836static void del_timeout(struct dlm_lkb *lkb)
1837{
1838 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1839
1840 mutex_lock(&ls->ls_timeout_mutex);
1841 if (!list_empty(&lkb->lkb_time_list)) {
1842 list_del_init(&lkb->lkb_time_list);
1843 unhold_lkb(lkb);
1844 }
1845 mutex_unlock(&ls->ls_timeout_mutex);
1846}
1847
1848/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1849 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1850 and then lock rsb because of lock ordering in add_timeout. We may need
1851 to specify some special timeout-related bits in the lkb that are just to
1852 be accessed under the timeout_mutex. */
1853
1854void dlm_scan_timeout(struct dlm_ls *ls)
1855{
1856 struct dlm_rsb *r;
1857 struct dlm_lkb *lkb;
1858 int do_cancel, do_warn;
1859 s64 wait_us;
1860
1861 for (;;) {
1862 if (dlm_locking_stopped(ls))
1863 break;
1864
1865 do_cancel = 0;
1866 do_warn = 0;
1867 mutex_lock(&ls->ls_timeout_mutex);
1868 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1869
1870 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1871 lkb->lkb_timestamp));
1872
1873 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
1874 wait_us >= (lkb->lkb_timeout_cs * 10000))
1875 do_cancel = 1;
1876
1877 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
1878 wait_us >= dlm_config.ci_timewarn_cs * 10000)
1879 do_warn = 1;
1880
1881 if (!do_cancel && !do_warn)
1882 continue;
1883 hold_lkb(lkb);
1884 break;
1885 }
1886 mutex_unlock(&ls->ls_timeout_mutex);
1887
1888 if (!do_cancel && !do_warn)
1889 break;
1890
1891 r = lkb->lkb_resource;
1892 hold_rsb(r);
1893 lock_rsb(r);
1894
1895 if (do_warn) {
1896 /* clear flag so we only warn once */
1897 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1898 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1899 del_timeout(lkb);
1900 dlm_timeout_warn(lkb);
1901 }
1902
1903 if (do_cancel) {
1904 log_debug(ls, "timeout cancel %x node %d %s",
1905 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1906 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1907 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1908 del_timeout(lkb);
1909 _cancel_lock(r, lkb);
1910 }
1911
1912 unlock_rsb(r);
1913 unhold_rsb(r);
1914 dlm_put_lkb(lkb);
1915 }
1916}
1917
1918/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1919 dlm_recoverd before checking/setting ls_recover_begin. */
1920
1921void dlm_adjust_timeouts(struct dlm_ls *ls)
1922{
1923 struct dlm_lkb *lkb;
1924 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
1925
1926 ls->ls_recover_begin = 0;
1927 mutex_lock(&ls->ls_timeout_mutex);
1928 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
1929 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
1930 mutex_unlock(&ls->ls_timeout_mutex);
1931
1932 if (!dlm_config.ci_waitwarn_us)
1933 return;
1934
1935 mutex_lock(&ls->ls_waiters_mutex);
1936 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1937 if (ktime_to_us(lkb->lkb_wait_time))
1938 lkb->lkb_wait_time = ktime_get();
1939 }
1940 mutex_unlock(&ls->ls_waiters_mutex);
1941}
1942
1943/* lkb is master or local copy */
1944
1945static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1946{
1947 int b, len = r->res_ls->ls_lvblen;
1948
1949 /* b=1 lvb returned to caller
1950 b=0 lvb written to rsb or invalidated
1951 b=-1 do nothing */
1952
1953 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1954
1955 if (b == 1) {
1956 if (!lkb->lkb_lvbptr)
1957 return;
1958
1959 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1960 return;
1961
1962 if (!r->res_lvbptr)
1963 return;
1964
1965 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1966 lkb->lkb_lvbseq = r->res_lvbseq;
1967
1968 } else if (b == 0) {
1969 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1970 rsb_set_flag(r, RSB_VALNOTVALID);
1971 return;
1972 }
1973
1974 if (!lkb->lkb_lvbptr)
1975 return;
1976
1977 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1978 return;
1979
1980 if (!r->res_lvbptr)
1981 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
1982
1983 if (!r->res_lvbptr)
1984 return;
1985
1986 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1987 r->res_lvbseq++;
1988 lkb->lkb_lvbseq = r->res_lvbseq;
1989 rsb_clear_flag(r, RSB_VALNOTVALID);
1990 }
1991
1992 if (rsb_flag(r, RSB_VALNOTVALID))
1993 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1994}
1995
1996static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1997{
1998 if (lkb->lkb_grmode < DLM_LOCK_PW)
1999 return;
2000
2001 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
2002 rsb_set_flag(r, RSB_VALNOTVALID);
2003 return;
2004 }
2005
2006 if (!lkb->lkb_lvbptr)
2007 return;
2008
2009 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2010 return;
2011
2012 if (!r->res_lvbptr)
2013 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
2014
2015 if (!r->res_lvbptr)
2016 return;
2017
2018 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2019 r->res_lvbseq++;
2020 rsb_clear_flag(r, RSB_VALNOTVALID);
2021}
2022
2023/* lkb is process copy (pc) */
2024
2025static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2026 struct dlm_message *ms)
2027{
2028 int b;
2029
2030 if (!lkb->lkb_lvbptr)
2031 return;
2032
2033 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2034 return;
2035
2036 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
2037 if (b == 1) {
2038 int len = receive_extralen(ms);
2039 if (len > r->res_ls->ls_lvblen)
2040 len = r->res_ls->ls_lvblen;
2041 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
2042 lkb->lkb_lvbseq = ms->m_lvbseq;
2043 }
2044}
2045
2046/* Manipulate lkb's on rsb's convert/granted/waiting queues
2047 remove_lock -- used for unlock, removes lkb from granted
2048 revert_lock -- used for cancel, moves lkb from convert to granted
2049 grant_lock -- used for request and convert, adds lkb to granted or
2050 moves lkb from convert or waiting to granted
2051
2052 Each of these is used for master or local copy lkb's. There is
2053 also a _pc() variation used to make the corresponding change on
2054 a process copy (pc) lkb. */
2055
2056static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2057{
2058 del_lkb(r, lkb);
2059 lkb->lkb_grmode = DLM_LOCK_IV;
2060 /* this unhold undoes the original ref from create_lkb()
2061 so this leads to the lkb being freed */
2062 unhold_lkb(lkb);
2063}
2064
2065static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2066{
2067 set_lvb_unlock(r, lkb);
2068 _remove_lock(r, lkb);
2069}
2070
2071static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2072{
2073 _remove_lock(r, lkb);
2074}
2075
2076/* returns: 0 did nothing
2077 1 moved lock to granted
2078 -1 removed lock */
2079
2080static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2081{
2082 int rv = 0;
2083
2084 lkb->lkb_rqmode = DLM_LOCK_IV;
2085
2086 switch (lkb->lkb_status) {
2087 case DLM_LKSTS_GRANTED:
2088 break;
2089 case DLM_LKSTS_CONVERT:
2090 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2091 rv = 1;
2092 break;
2093 case DLM_LKSTS_WAITING:
2094 del_lkb(r, lkb);
2095 lkb->lkb_grmode = DLM_LOCK_IV;
2096 /* this unhold undoes the original ref from create_lkb()
2097 so this leads to the lkb being freed */
2098 unhold_lkb(lkb);
2099 rv = -1;
2100 break;
2101 default:
2102 log_print("invalid status for revert %d", lkb->lkb_status);
2103 }
2104 return rv;
2105}
2106
2107static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2108{
2109 return revert_lock(r, lkb);
2110}
2111
2112static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2113{
2114 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
2115 lkb->lkb_grmode = lkb->lkb_rqmode;
2116 if (lkb->lkb_status)
2117 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2118 else
2119 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
2120 }
2121
2122 lkb->lkb_rqmode = DLM_LOCK_IV;
2123 lkb->lkb_highbast = 0;
2124}
2125
2126static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2127{
2128 set_lvb_lock(r, lkb);
2129 _grant_lock(r, lkb);
2130}
2131
2132static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2133 struct dlm_message *ms)
2134{
2135 set_lvb_lock_pc(r, lkb, ms);
2136 _grant_lock(r, lkb);
2137}
2138
2139/* called by grant_pending_locks() which means an async grant message must
2140 be sent to the requesting node in addition to granting the lock if the
2141 lkb belongs to a remote node. */
2142
2143static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
2144{
2145 grant_lock(r, lkb);
2146 if (is_master_copy(lkb))
2147 send_grant(r, lkb);
2148 else
2149 queue_cast(r, lkb, 0);
2150}
2151
2152/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
2153 change the granted/requested modes. We're munging things accordingly in
2154 the process copy.
2155 CONVDEADLK: our grmode may have been forced down to NL to resolve a
2156 conversion deadlock
2157 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
2158 compatible with other granted locks */
2159
2160static void munge_demoted(struct dlm_lkb *lkb)
2161{
2162 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
2163 log_print("munge_demoted %x invalid modes gr %d rq %d",
2164 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
2165 return;
2166 }
2167
2168 lkb->lkb_grmode = DLM_LOCK_NL;
2169}
2170
2171static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
2172{
2173 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
2174 ms->m_type != DLM_MSG_GRANT) {
2175 log_print("munge_altmode %x invalid reply type %d",
2176 lkb->lkb_id, ms->m_type);
2177 return;
2178 }
2179
2180 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
2181 lkb->lkb_rqmode = DLM_LOCK_PR;
2182 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
2183 lkb->lkb_rqmode = DLM_LOCK_CW;
2184 else {
2185 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
2186 dlm_print_lkb(lkb);
2187 }
2188}
2189
2190static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
2191{
2192 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
2193 lkb_statequeue);
2194 if (lkb->lkb_id == first->lkb_id)
2195 return 1;
2196
2197 return 0;
2198}
2199
2200/* Check if the given lkb conflicts with another lkb on the queue. */
2201
2202static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
2203{
2204 struct dlm_lkb *this;
2205
2206 list_for_each_entry(this, head, lkb_statequeue) {
2207 if (this == lkb)
2208 continue;
2209 if (!modes_compat(this, lkb))
2210 return 1;
2211 }
2212 return 0;
2213}
2214
2215/*
2216 * "A conversion deadlock arises with a pair of lock requests in the converting
2217 * queue for one resource. The granted mode of each lock blocks the requested
2218 * mode of the other lock."
2219 *
2220 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
2221 * convert queue from being granted, then deadlk/demote lkb.
2222 *
2223 * Example:
2224 * Granted Queue: empty
2225 * Convert Queue: NL->EX (first lock)
2226 * PR->EX (second lock)
2227 *
2228 * The first lock can't be granted because of the granted mode of the second
2229 * lock and the second lock can't be granted because it's not first in the
2230 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2231 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2232 * flag set and return DEMOTED in the lksb flags.
2233 *
2234 * Originally, this function detected conv-deadlk in a more limited scope:
2235 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2236 * - if lkb1 was the first entry in the queue (not just earlier), and was
2237 * blocked by the granted mode of lkb2, and there was nothing on the
2238 * granted queue preventing lkb1 from being granted immediately, i.e.
2239 * lkb2 was the only thing preventing lkb1 from being granted.
2240 *
2241 * That second condition meant we'd only say there was conv-deadlk if
2242 * resolving it (by demotion) would lead to the first lock on the convert
2243 * queue being granted right away. It allowed conversion deadlocks to exist
2244 * between locks on the convert queue while they couldn't be granted anyway.
2245 *
2246 * Now, we detect and take action on conversion deadlocks immediately when
2247 * they're created, even if they may not be immediately consequential. If
2248 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2249 * mode that would prevent lkb1's conversion from being granted, we do a
2250 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2251 * I think this means that the lkb_is_ahead condition below should always
2252 * be zero, i.e. there will never be conv-deadlk between two locks that are
2253 * both already on the convert queue.
2254 */
2255
2256static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
2257{
2258 struct dlm_lkb *lkb1;
2259 int lkb_is_ahead = 0;
2260
2261 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2262 if (lkb1 == lkb2) {
2263 lkb_is_ahead = 1;
2264 continue;
2265 }
2266
2267 if (!lkb_is_ahead) {
2268 if (!modes_compat(lkb2, lkb1))
2269 return 1;
2270 } else {
2271 if (!modes_compat(lkb2, lkb1) &&
2272 !modes_compat(lkb1, lkb2))
2273 return 1;
2274 }
2275 }
2276 return 0;
2277}
2278
2279/*
2280 * Return 1 if the lock can be granted, 0 otherwise.
2281 * Also detect and resolve conversion deadlocks.
2282 *
2283 * lkb is the lock to be granted
2284 *
2285 * now is 1 if the function is being called in the context of the
2286 * immediate request, it is 0 if called later, after the lock has been
2287 * queued.
2288 *
2289 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2290 * after recovery.
2291 *
2292 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2293 */
2294
2295static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2296 int recover)
2297{
2298 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2299
2300 /*
2301 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2302 * a new request for a NL mode lock being blocked.
2303 *
2304 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2305 * request, then it would be granted. In essence, the use of this flag
2306 * tells the Lock Manager to expedite theis request by not considering
2307 * what may be in the CONVERTING or WAITING queues... As of this
2308 * writing, the EXPEDITE flag can be used only with new requests for NL
2309 * mode locks. This flag is not valid for conversion requests.
2310 *
2311 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2312 * conversion or used with a non-NL requested mode. We also know an
2313 * EXPEDITE request is always granted immediately, so now must always
2314 * be 1. The full condition to grant an expedite request: (now &&
2315 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2316 * therefore be shortened to just checking the flag.
2317 */
2318
2319 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
2320 return 1;
2321
2322 /*
2323 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2324 * added to the remaining conditions.
2325 */
2326
2327 if (queue_conflict(&r->res_grantqueue, lkb))
2328 return 0;
2329
2330 /*
2331 * 6-3: By default, a conversion request is immediately granted if the
2332 * requested mode is compatible with the modes of all other granted
2333 * locks
2334 */
2335
2336 if (queue_conflict(&r->res_convertqueue, lkb))
2337 return 0;
2338
2339 /*
2340 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2341 * locks for a recovered rsb, on which lkb's have been rebuilt.
2342 * The lkb's may have been rebuilt on the queues in a different
2343 * order than they were in on the previous master. So, granting
2344 * queued conversions in order after recovery doesn't make sense
2345 * since the order hasn't been preserved anyway. The new order
2346 * could also have created a new "in place" conversion deadlock.
2347 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2348 * After recovery, there would be no granted locks, and possibly
2349 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2350 * recovery, grant conversions without considering order.
2351 */
2352
2353 if (conv && recover)
2354 return 1;
2355
2356 /*
2357 * 6-5: But the default algorithm for deciding whether to grant or
2358 * queue conversion requests does not by itself guarantee that such
2359 * requests are serviced on a "first come first serve" basis. This, in
2360 * turn, can lead to a phenomenon known as "indefinate postponement".
2361 *
2362 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2363 * the system service employed to request a lock conversion. This flag
2364 * forces certain conversion requests to be queued, even if they are
2365 * compatible with the granted modes of other locks on the same
2366 * resource. Thus, the use of this flag results in conversion requests
2367 * being ordered on a "first come first servce" basis.
2368 *
2369 * DCT: This condition is all about new conversions being able to occur
2370 * "in place" while the lock remains on the granted queue (assuming
2371 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2372 * doesn't _have_ to go onto the convert queue where it's processed in
2373 * order. The "now" variable is necessary to distinguish converts
2374 * being received and processed for the first time now, because once a
2375 * convert is moved to the conversion queue the condition below applies
2376 * requiring fifo granting.
2377 */
2378
2379 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
2380 return 1;
2381
2382 /*
2383 * Even if the convert is compat with all granted locks,
2384 * QUECVT forces it behind other locks on the convert queue.
2385 */
2386
2387 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2388 if (list_empty(&r->res_convertqueue))
2389 return 1;
2390 else
2391 return 0;
2392 }
2393
2394 /*
2395 * The NOORDER flag is set to avoid the standard vms rules on grant
2396 * order.
2397 */
2398
2399 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
2400 return 1;
2401
2402 /*
2403 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2404 * granted until all other conversion requests ahead of it are granted
2405 * and/or canceled.
2406 */
2407
2408 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
2409 return 1;
2410
2411 /*
2412 * 6-4: By default, a new request is immediately granted only if all
2413 * three of the following conditions are satisfied when the request is
2414 * issued:
2415 * - The queue of ungranted conversion requests for the resource is
2416 * empty.
2417 * - The queue of ungranted new requests for the resource is empty.
2418 * - The mode of the new request is compatible with the most
2419 * restrictive mode of all granted locks on the resource.
2420 */
2421
2422 if (now && !conv && list_empty(&r->res_convertqueue) &&
2423 list_empty(&r->res_waitqueue))
2424 return 1;
2425
2426 /*
2427 * 6-4: Once a lock request is in the queue of ungranted new requests,
2428 * it cannot be granted until the queue of ungranted conversion
2429 * requests is empty, all ungranted new requests ahead of it are
2430 * granted and/or canceled, and it is compatible with the granted mode
2431 * of the most restrictive lock granted on the resource.
2432 */
2433
2434 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2435 first_in_list(lkb, &r->res_waitqueue))
2436 return 1;
2437
2438 return 0;
2439}
2440
2441static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2442 int recover, int *err)
2443{
2444 int rv;
2445 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
2446 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2447
2448 if (err)
2449 *err = 0;
2450
2451 rv = _can_be_granted(r, lkb, now, recover);
2452 if (rv)
2453 goto out;
2454
2455 /*
2456 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2457 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2458 * cancels one of the locks.
2459 */
2460
2461 if (is_convert && can_be_queued(lkb) &&
2462 conversion_deadlock_detect(r, lkb)) {
2463 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2464 lkb->lkb_grmode = DLM_LOCK_NL;
2465 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
2466 } else if (err) {
2467 *err = -EDEADLK;
2468 } else {
2469 log_print("can_be_granted deadlock %x now %d",
2470 lkb->lkb_id, now);
2471 dlm_dump_rsb(r);
2472 }
2473 goto out;
2474 }
2475
2476 /*
2477 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2478 * to grant a request in a mode other than the normal rqmode. It's a
2479 * simple way to provide a big optimization to applications that can
2480 * use them.
2481 */
2482
2483 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
2484 alt = DLM_LOCK_PR;
2485 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
2486 alt = DLM_LOCK_CW;
2487
2488 if (alt) {
2489 lkb->lkb_rqmode = alt;
2490 rv = _can_be_granted(r, lkb, now, 0);
2491 if (rv)
2492 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
2493 else
2494 lkb->lkb_rqmode = rqmode;
2495 }
2496 out:
2497 return rv;
2498}
2499
2500/* Returns the highest requested mode of all blocked conversions; sets
2501 cw if there's a blocked conversion to DLM_LOCK_CW. */
2502
2503static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2504 unsigned int *count)
2505{
2506 struct dlm_lkb *lkb, *s;
2507 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
2508 int hi, demoted, quit, grant_restart, demote_restart;
2509 int deadlk;
2510
2511 quit = 0;
2512 restart:
2513 grant_restart = 0;
2514 demote_restart = 0;
2515 hi = DLM_LOCK_IV;
2516
2517 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2518 demoted = is_demoted(lkb);
2519 deadlk = 0;
2520
2521 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
2522 grant_lock_pending(r, lkb);
2523 grant_restart = 1;
2524 if (count)
2525 (*count)++;
2526 continue;
2527 }
2528
2529 if (!demoted && is_demoted(lkb)) {
2530 log_print("WARN: pending demoted %x node %d %s",
2531 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2532 demote_restart = 1;
2533 continue;
2534 }
2535
2536 if (deadlk) {
2537 /*
2538 * If DLM_LKB_NODLKWT flag is set and conversion
2539 * deadlock is detected, we request blocking AST and
2540 * down (or cancel) conversion.
2541 */
2542 if (lkb->lkb_exflags & DLM_LKF_NODLCKWT) {
2543 if (lkb->lkb_highbast < lkb->lkb_rqmode) {
2544 queue_bast(r, lkb, lkb->lkb_rqmode);
2545 lkb->lkb_highbast = lkb->lkb_rqmode;
2546 }
2547 } else {
2548 log_print("WARN: pending deadlock %x node %d %s",
2549 lkb->lkb_id, lkb->lkb_nodeid,
2550 r->res_name);
2551 dlm_dump_rsb(r);
2552 }
2553 continue;
2554 }
2555
2556 hi = max_t(int, lkb->lkb_rqmode, hi);
2557
2558 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2559 *cw = 1;
2560 }
2561
2562 if (grant_restart)
2563 goto restart;
2564 if (demote_restart && !quit) {
2565 quit = 1;
2566 goto restart;
2567 }
2568
2569 return max_t(int, high, hi);
2570}
2571
2572static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2573 unsigned int *count)
2574{
2575 struct dlm_lkb *lkb, *s;
2576
2577 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
2578 if (can_be_granted(r, lkb, 0, 0, NULL)) {
2579 grant_lock_pending(r, lkb);
2580 if (count)
2581 (*count)++;
2582 } else {
2583 high = max_t(int, lkb->lkb_rqmode, high);
2584 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2585 *cw = 1;
2586 }
2587 }
2588
2589 return high;
2590}
2591
2592/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2593 on either the convert or waiting queue.
2594 high is the largest rqmode of all locks blocked on the convert or
2595 waiting queue. */
2596
2597static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2598{
2599 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2600 if (gr->lkb_highbast < DLM_LOCK_EX)
2601 return 1;
2602 return 0;
2603 }
2604
2605 if (gr->lkb_highbast < high &&
2606 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2607 return 1;
2608 return 0;
2609}
2610
2611static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
2612{
2613 struct dlm_lkb *lkb, *s;
2614 int high = DLM_LOCK_IV;
2615 int cw = 0;
2616
2617 if (!is_master(r)) {
2618 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2619 dlm_dump_rsb(r);
2620 return;
2621 }
2622
2623 high = grant_pending_convert(r, high, &cw, count);
2624 high = grant_pending_wait(r, high, &cw, count);
2625
2626 if (high == DLM_LOCK_IV)
2627 return;
2628
2629 /*
2630 * If there are locks left on the wait/convert queue then send blocking
2631 * ASTs to granted locks based on the largest requested mode (high)
2632 * found above.
2633 */
2634
2635 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
2636 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
2637 if (cw && high == DLM_LOCK_PR &&
2638 lkb->lkb_grmode == DLM_LOCK_PR)
2639 queue_bast(r, lkb, DLM_LOCK_CW);
2640 else
2641 queue_bast(r, lkb, high);
2642 lkb->lkb_highbast = high;
2643 }
2644 }
2645}
2646
2647static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2648{
2649 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2650 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2651 if (gr->lkb_highbast < DLM_LOCK_EX)
2652 return 1;
2653 return 0;
2654 }
2655
2656 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2657 return 1;
2658 return 0;
2659}
2660
2661static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2662 struct dlm_lkb *lkb)
2663{
2664 struct dlm_lkb *gr;
2665
2666 list_for_each_entry(gr, head, lkb_statequeue) {
2667 /* skip self when sending basts to convertqueue */
2668 if (gr == lkb)
2669 continue;
2670 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
2671 queue_bast(r, gr, lkb->lkb_rqmode);
2672 gr->lkb_highbast = lkb->lkb_rqmode;
2673 }
2674 }
2675}
2676
2677static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2678{
2679 send_bast_queue(r, &r->res_grantqueue, lkb);
2680}
2681
2682static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2683{
2684 send_bast_queue(r, &r->res_grantqueue, lkb);
2685 send_bast_queue(r, &r->res_convertqueue, lkb);
2686}
2687
2688/* set_master(r, lkb) -- set the master nodeid of a resource
2689
2690 The purpose of this function is to set the nodeid field in the given
2691 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2692 known, it can just be copied to the lkb and the function will return
2693 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2694 before it can be copied to the lkb.
2695
2696 When the rsb nodeid is being looked up remotely, the initial lkb
2697 causing the lookup is kept on the ls_waiters list waiting for the
2698 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2699 on the rsb's res_lookup list until the master is verified.
2700
2701 Return values:
2702 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2703 1: the rsb master is not available and the lkb has been placed on
2704 a wait queue
2705*/
2706
2707static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2708{
2709 int our_nodeid = dlm_our_nodeid();
2710
2711 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2712 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2713 r->res_first_lkid = lkb->lkb_id;
2714 lkb->lkb_nodeid = r->res_nodeid;
2715 return 0;
2716 }
2717
2718 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2719 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2720 return 1;
2721 }
2722
2723 if (r->res_master_nodeid == our_nodeid) {
2724 lkb->lkb_nodeid = 0;
2725 return 0;
2726 }
2727
2728 if (r->res_master_nodeid) {
2729 lkb->lkb_nodeid = r->res_master_nodeid;
2730 return 0;
2731 }
2732
2733 if (dlm_dir_nodeid(r) == our_nodeid) {
2734 /* This is a somewhat unusual case; find_rsb will usually
2735 have set res_master_nodeid when dir nodeid is local, but
2736 there are cases where we become the dir node after we've
2737 past find_rsb and go through _request_lock again.
2738 confirm_master() or process_lookup_list() needs to be
2739 called after this. */
2740 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2741 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2742 r->res_name);
2743 r->res_master_nodeid = our_nodeid;
2744 r->res_nodeid = 0;
2745 lkb->lkb_nodeid = 0;
2746 return 0;
2747 }
2748
2749 wait_pending_remove(r);
2750
2751 r->res_first_lkid = lkb->lkb_id;
2752 send_lookup(r, lkb);
2753 return 1;
2754}
2755
2756static void process_lookup_list(struct dlm_rsb *r)
2757{
2758 struct dlm_lkb *lkb, *safe;
2759
2760 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
2761 list_del_init(&lkb->lkb_rsb_lookup);
2762 _request_lock(r, lkb);
2763 schedule();
2764 }
2765}
2766
2767/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2768
2769static void confirm_master(struct dlm_rsb *r, int error)
2770{
2771 struct dlm_lkb *lkb;
2772
2773 if (!r->res_first_lkid)
2774 return;
2775
2776 switch (error) {
2777 case 0:
2778 case -EINPROGRESS:
2779 r->res_first_lkid = 0;
2780 process_lookup_list(r);
2781 break;
2782
2783 case -EAGAIN:
2784 case -EBADR:
2785 case -ENOTBLK:
2786 /* the remote request failed and won't be retried (it was
2787 a NOQUEUE, or has been canceled/unlocked); make a waiting
2788 lkb the first_lkid */
2789
2790 r->res_first_lkid = 0;
2791
2792 if (!list_empty(&r->res_lookup)) {
2793 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2794 lkb_rsb_lookup);
2795 list_del_init(&lkb->lkb_rsb_lookup);
2796 r->res_first_lkid = lkb->lkb_id;
2797 _request_lock(r, lkb);
2798 }
2799 break;
2800
2801 default:
2802 log_error(r->res_ls, "confirm_master unknown error %d", error);
2803 }
2804}
2805
2806static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
2807 int namelen, unsigned long timeout_cs,
2808 void (*ast) (void *astparam),
2809 void *astparam,
2810 void (*bast) (void *astparam, int mode),
2811 struct dlm_args *args)
2812{
2813 int rv = -EINVAL;
2814
2815 /* check for invalid arg usage */
2816
2817 if (mode < 0 || mode > DLM_LOCK_EX)
2818 goto out;
2819
2820 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2821 goto out;
2822
2823 if (flags & DLM_LKF_CANCEL)
2824 goto out;
2825
2826 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2827 goto out;
2828
2829 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2830 goto out;
2831
2832 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2833 goto out;
2834
2835 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2836 goto out;
2837
2838 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2839 goto out;
2840
2841 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2842 goto out;
2843
2844 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2845 goto out;
2846
2847 if (!ast || !lksb)
2848 goto out;
2849
2850 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2851 goto out;
2852
2853 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2854 goto out;
2855
2856 /* these args will be copied to the lkb in validate_lock_args,
2857 it cannot be done now because when converting locks, fields in
2858 an active lkb cannot be modified before locking the rsb */
2859
2860 args->flags = flags;
2861 args->astfn = ast;
2862 args->astparam = astparam;
2863 args->bastfn = bast;
2864 args->timeout = timeout_cs;
2865 args->mode = mode;
2866 args->lksb = lksb;
2867 rv = 0;
2868 out:
2869 return rv;
2870}
2871
2872static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2873{
2874 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2875 DLM_LKF_FORCEUNLOCK))
2876 return -EINVAL;
2877
2878 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2879 return -EINVAL;
2880
2881 args->flags = flags;
2882 args->astparam = astarg;
2883 return 0;
2884}
2885
2886static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2887 struct dlm_args *args)
2888{
2889 int rv = -EINVAL;
2890
2891 if (args->flags & DLM_LKF_CONVERT) {
2892 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2893 goto out;
2894
2895 if (args->flags & DLM_LKF_QUECVT &&
2896 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2897 goto out;
2898
2899 rv = -EBUSY;
2900 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2901 goto out;
2902
2903 if (lkb->lkb_wait_type)
2904 goto out;
2905
2906 if (is_overlap(lkb))
2907 goto out;
2908 }
2909
2910 lkb->lkb_exflags = args->flags;
2911 lkb->lkb_sbflags = 0;
2912 lkb->lkb_astfn = args->astfn;
2913 lkb->lkb_astparam = args->astparam;
2914 lkb->lkb_bastfn = args->bastfn;
2915 lkb->lkb_rqmode = args->mode;
2916 lkb->lkb_lksb = args->lksb;
2917 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2918 lkb->lkb_ownpid = (int) current->pid;
2919 lkb->lkb_timeout_cs = args->timeout;
2920 rv = 0;
2921 out:
2922 if (rv)
2923 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2924 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2925 lkb->lkb_status, lkb->lkb_wait_type,
2926 lkb->lkb_resource->res_name);
2927 return rv;
2928}
2929
2930/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2931 for success */
2932
2933/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2934 because there may be a lookup in progress and it's valid to do
2935 cancel/unlockf on it */
2936
2937static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2938{
2939 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
2940 int rv = -EINVAL;
2941
2942 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2943 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2944 dlm_print_lkb(lkb);
2945 goto out;
2946 }
2947
2948 /* an lkb may still exist even though the lock is EOL'ed due to a
2949 cancel, unlock or failed noqueue request; an app can't use these
2950 locks; return same error as if the lkid had not been found at all */
2951
2952 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2953 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2954 rv = -ENOENT;
2955 goto out;
2956 }
2957
2958 /* an lkb may be waiting for an rsb lookup to complete where the
2959 lookup was initiated by another lock */
2960
2961 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2962 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
2963 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2964 list_del_init(&lkb->lkb_rsb_lookup);
2965 queue_cast(lkb->lkb_resource, lkb,
2966 args->flags & DLM_LKF_CANCEL ?
2967 -DLM_ECANCEL : -DLM_EUNLOCK);
2968 unhold_lkb(lkb); /* undoes create_lkb() */
2969 }
2970 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2971 rv = -EBUSY;
2972 goto out;
2973 }
2974
2975 /* cancel not allowed with another cancel/unlock in progress */
2976
2977 if (args->flags & DLM_LKF_CANCEL) {
2978 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2979 goto out;
2980
2981 if (is_overlap(lkb))
2982 goto out;
2983
2984 /* don't let scand try to do a cancel */
2985 del_timeout(lkb);
2986
2987 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2988 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2989 rv = -EBUSY;
2990 goto out;
2991 }
2992
2993 /* there's nothing to cancel */
2994 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2995 !lkb->lkb_wait_type) {
2996 rv = -EBUSY;
2997 goto out;
2998 }
2999
3000 switch (lkb->lkb_wait_type) {
3001 case DLM_MSG_LOOKUP:
3002 case DLM_MSG_REQUEST:
3003 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
3004 rv = -EBUSY;
3005 goto out;
3006 case DLM_MSG_UNLOCK:
3007 case DLM_MSG_CANCEL:
3008 goto out;
3009 }
3010 /* add_to_waiters() will set OVERLAP_CANCEL */
3011 goto out_ok;
3012 }
3013
3014 /* do we need to allow a force-unlock if there's a normal unlock
3015 already in progress? in what conditions could the normal unlock
3016 fail such that we'd want to send a force-unlock to be sure? */
3017
3018 if (args->flags & DLM_LKF_FORCEUNLOCK) {
3019 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
3020 goto out;
3021
3022 if (is_overlap_unlock(lkb))
3023 goto out;
3024
3025 /* don't let scand try to do a cancel */
3026 del_timeout(lkb);
3027
3028 if (lkb->lkb_flags & DLM_IFL_RESEND) {
3029 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3030 rv = -EBUSY;
3031 goto out;
3032 }
3033
3034 switch (lkb->lkb_wait_type) {
3035 case DLM_MSG_LOOKUP:
3036 case DLM_MSG_REQUEST:
3037 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3038 rv = -EBUSY;
3039 goto out;
3040 case DLM_MSG_UNLOCK:
3041 goto out;
3042 }
3043 /* add_to_waiters() will set OVERLAP_UNLOCK */
3044 goto out_ok;
3045 }
3046
3047 /* normal unlock not allowed if there's any op in progress */
3048 rv = -EBUSY;
3049 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
3050 goto out;
3051
3052 out_ok:
3053 /* an overlapping op shouldn't blow away exflags from other op */
3054 lkb->lkb_exflags |= args->flags;
3055 lkb->lkb_sbflags = 0;
3056 lkb->lkb_astparam = args->astparam;
3057 rv = 0;
3058 out:
3059 if (rv)
3060 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
3061 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
3062 args->flags, lkb->lkb_wait_type,
3063 lkb->lkb_resource->res_name);
3064 return rv;
3065}
3066
3067/*
3068 * Four stage 4 varieties:
3069 * do_request(), do_convert(), do_unlock(), do_cancel()
3070 * These are called on the master node for the given lock and
3071 * from the central locking logic.
3072 */
3073
3074static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3075{
3076 int error = 0;
3077
3078 if (can_be_granted(r, lkb, 1, 0, NULL)) {
3079 grant_lock(r, lkb);
3080 queue_cast(r, lkb, 0);
3081 goto out;
3082 }
3083
3084 if (can_be_queued(lkb)) {
3085 error = -EINPROGRESS;
3086 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3087 add_timeout(lkb);
3088 goto out;
3089 }
3090
3091 error = -EAGAIN;
3092 queue_cast(r, lkb, -EAGAIN);
3093 out:
3094 return error;
3095}
3096
3097static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3098 int error)
3099{
3100 switch (error) {
3101 case -EAGAIN:
3102 if (force_blocking_asts(lkb))
3103 send_blocking_asts_all(r, lkb);
3104 break;
3105 case -EINPROGRESS:
3106 send_blocking_asts(r, lkb);
3107 break;
3108 }
3109}
3110
3111static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3112{
3113 int error = 0;
3114 int deadlk = 0;
3115
3116 /* changing an existing lock may allow others to be granted */
3117
3118 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
3119 grant_lock(r, lkb);
3120 queue_cast(r, lkb, 0);
3121 goto out;
3122 }
3123
3124 /* can_be_granted() detected that this lock would block in a conversion
3125 deadlock, so we leave it on the granted queue and return EDEADLK in
3126 the ast for the convert. */
3127
3128 if (deadlk && !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
3129 /* it's left on the granted queue */
3130 revert_lock(r, lkb);
3131 queue_cast(r, lkb, -EDEADLK);
3132 error = -EDEADLK;
3133 goto out;
3134 }
3135
3136 /* is_demoted() means the can_be_granted() above set the grmode
3137 to NL, and left us on the granted queue. This auto-demotion
3138 (due to CONVDEADLK) might mean other locks, and/or this lock, are
3139 now grantable. We have to try to grant other converting locks
3140 before we try again to grant this one. */
3141
3142 if (is_demoted(lkb)) {
3143 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
3144 if (_can_be_granted(r, lkb, 1, 0)) {
3145 grant_lock(r, lkb);
3146 queue_cast(r, lkb, 0);
3147 goto out;
3148 }
3149 /* else fall through and move to convert queue */
3150 }
3151
3152 if (can_be_queued(lkb)) {
3153 error = -EINPROGRESS;
3154 del_lkb(r, lkb);
3155 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3156 add_timeout(lkb);
3157 goto out;
3158 }
3159
3160 error = -EAGAIN;
3161 queue_cast(r, lkb, -EAGAIN);
3162 out:
3163 return error;
3164}
3165
3166static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3167 int error)
3168{
3169 switch (error) {
3170 case 0:
3171 grant_pending_locks(r, NULL);
3172 /* grant_pending_locks also sends basts */
3173 break;
3174 case -EAGAIN:
3175 if (force_blocking_asts(lkb))
3176 send_blocking_asts_all(r, lkb);
3177 break;
3178 case -EINPROGRESS:
3179 send_blocking_asts(r, lkb);
3180 break;
3181 }
3182}
3183
3184static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3185{
3186 remove_lock(r, lkb);
3187 queue_cast(r, lkb, -DLM_EUNLOCK);
3188 return -DLM_EUNLOCK;
3189}
3190
3191static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3192 int error)
3193{
3194 grant_pending_locks(r, NULL);
3195}
3196
3197/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
3198
3199static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3200{
3201 int error;
3202
3203 error = revert_lock(r, lkb);
3204 if (error) {
3205 queue_cast(r, lkb, -DLM_ECANCEL);
3206 return -DLM_ECANCEL;
3207 }
3208 return 0;
3209}
3210
3211static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3212 int error)
3213{
3214 if (error)
3215 grant_pending_locks(r, NULL);
3216}
3217
3218/*
3219 * Four stage 3 varieties:
3220 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3221 */
3222
3223/* add a new lkb to a possibly new rsb, called by requesting process */
3224
3225static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3226{
3227 int error;
3228
3229 /* set_master: sets lkb nodeid from r */
3230
3231 error = set_master(r, lkb);
3232 if (error < 0)
3233 goto out;
3234 if (error) {
3235 error = 0;
3236 goto out;
3237 }
3238
3239 if (is_remote(r)) {
3240 /* receive_request() calls do_request() on remote node */
3241 error = send_request(r, lkb);
3242 } else {
3243 error = do_request(r, lkb);
3244 /* for remote locks the request_reply is sent
3245 between do_request and do_request_effects */
3246 do_request_effects(r, lkb, error);
3247 }
3248 out:
3249 return error;
3250}
3251
3252/* change some property of an existing lkb, e.g. mode */
3253
3254static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3255{
3256 int error;
3257
3258 if (is_remote(r)) {
3259 /* receive_convert() calls do_convert() on remote node */
3260 error = send_convert(r, lkb);
3261 } else {
3262 error = do_convert(r, lkb);
3263 /* for remote locks the convert_reply is sent
3264 between do_convert and do_convert_effects */
3265 do_convert_effects(r, lkb, error);
3266 }
3267
3268 return error;
3269}
3270
3271/* remove an existing lkb from the granted queue */
3272
3273static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3274{
3275 int error;
3276
3277 if (is_remote(r)) {
3278 /* receive_unlock() calls do_unlock() on remote node */
3279 error = send_unlock(r, lkb);
3280 } else {
3281 error = do_unlock(r, lkb);
3282 /* for remote locks the unlock_reply is sent
3283 between do_unlock and do_unlock_effects */
3284 do_unlock_effects(r, lkb, error);
3285 }
3286
3287 return error;
3288}
3289
3290/* remove an existing lkb from the convert or wait queue */
3291
3292static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3293{
3294 int error;
3295
3296 if (is_remote(r)) {
3297 /* receive_cancel() calls do_cancel() on remote node */
3298 error = send_cancel(r, lkb);
3299 } else {
3300 error = do_cancel(r, lkb);
3301 /* for remote locks the cancel_reply is sent
3302 between do_cancel and do_cancel_effects */
3303 do_cancel_effects(r, lkb, error);
3304 }
3305
3306 return error;
3307}
3308
3309/*
3310 * Four stage 2 varieties:
3311 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3312 */
3313
3314static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
3315 int len, struct dlm_args *args)
3316{
3317 struct dlm_rsb *r;
3318 int error;
3319
3320 error = validate_lock_args(ls, lkb, args);
3321 if (error)
3322 return error;
3323
3324 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
3325 if (error)
3326 return error;
3327
3328 lock_rsb(r);
3329
3330 attach_lkb(r, lkb);
3331 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3332
3333 error = _request_lock(r, lkb);
3334
3335 unlock_rsb(r);
3336 put_rsb(r);
3337 return error;
3338}
3339
3340static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3341 struct dlm_args *args)
3342{
3343 struct dlm_rsb *r;
3344 int error;
3345
3346 r = lkb->lkb_resource;
3347
3348 hold_rsb(r);
3349 lock_rsb(r);
3350
3351 error = validate_lock_args(ls, lkb, args);
3352 if (error)
3353 goto out;
3354
3355 error = _convert_lock(r, lkb);
3356 out:
3357 unlock_rsb(r);
3358 put_rsb(r);
3359 return error;
3360}
3361
3362static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3363 struct dlm_args *args)
3364{
3365 struct dlm_rsb *r;
3366 int error;
3367
3368 r = lkb->lkb_resource;
3369
3370 hold_rsb(r);
3371 lock_rsb(r);
3372
3373 error = validate_unlock_args(lkb, args);
3374 if (error)
3375 goto out;
3376
3377 error = _unlock_lock(r, lkb);
3378 out:
3379 unlock_rsb(r);
3380 put_rsb(r);
3381 return error;
3382}
3383
3384static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3385 struct dlm_args *args)
3386{
3387 struct dlm_rsb *r;
3388 int error;
3389
3390 r = lkb->lkb_resource;
3391
3392 hold_rsb(r);
3393 lock_rsb(r);
3394
3395 error = validate_unlock_args(lkb, args);
3396 if (error)
3397 goto out;
3398
3399 error = _cancel_lock(r, lkb);
3400 out:
3401 unlock_rsb(r);
3402 put_rsb(r);
3403 return error;
3404}
3405
3406/*
3407 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3408 */
3409
3410int dlm_lock(dlm_lockspace_t *lockspace,
3411 int mode,
3412 struct dlm_lksb *lksb,
3413 uint32_t flags,
3414 void *name,
3415 unsigned int namelen,
3416 uint32_t parent_lkid,
3417 void (*ast) (void *astarg),
3418 void *astarg,
3419 void (*bast) (void *astarg, int mode))
3420{
3421 struct dlm_ls *ls;
3422 struct dlm_lkb *lkb;
3423 struct dlm_args args;
3424 int error, convert = flags & DLM_LKF_CONVERT;
3425
3426 ls = dlm_find_lockspace_local(lockspace);
3427 if (!ls)
3428 return -EINVAL;
3429
3430 dlm_lock_recovery(ls);
3431
3432 if (convert)
3433 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3434 else
3435 error = create_lkb(ls, &lkb);
3436
3437 if (error)
3438 goto out;
3439
3440 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3441 astarg, bast, &args);
3442 if (error)
3443 goto out_put;
3444
3445 if (convert)
3446 error = convert_lock(ls, lkb, &args);
3447 else
3448 error = request_lock(ls, lkb, name, namelen, &args);
3449
3450 if (error == -EINPROGRESS)
3451 error = 0;
3452 out_put:
3453 if (convert || error)
3454 __put_lkb(ls, lkb);
3455 if (error == -EAGAIN || error == -EDEADLK)
3456 error = 0;
3457 out:
3458 dlm_unlock_recovery(ls);
3459 dlm_put_lockspace(ls);
3460 return error;
3461}
3462
3463int dlm_unlock(dlm_lockspace_t *lockspace,
3464 uint32_t lkid,
3465 uint32_t flags,
3466 struct dlm_lksb *lksb,
3467 void *astarg)
3468{
3469 struct dlm_ls *ls;
3470 struct dlm_lkb *lkb;
3471 struct dlm_args args;
3472 int error;
3473
3474 ls = dlm_find_lockspace_local(lockspace);
3475 if (!ls)
3476 return -EINVAL;
3477
3478 dlm_lock_recovery(ls);
3479
3480 error = find_lkb(ls, lkid, &lkb);
3481 if (error)
3482 goto out;
3483
3484 error = set_unlock_args(flags, astarg, &args);
3485 if (error)
3486 goto out_put;
3487
3488 if (flags & DLM_LKF_CANCEL)
3489 error = cancel_lock(ls, lkb, &args);
3490 else
3491 error = unlock_lock(ls, lkb, &args);
3492
3493 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3494 error = 0;
3495 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3496 error = 0;
3497 out_put:
3498 dlm_put_lkb(lkb);
3499 out:
3500 dlm_unlock_recovery(ls);
3501 dlm_put_lockspace(ls);
3502 return error;
3503}
3504
3505/*
3506 * send/receive routines for remote operations and replies
3507 *
3508 * send_args
3509 * send_common
3510 * send_request receive_request
3511 * send_convert receive_convert
3512 * send_unlock receive_unlock
3513 * send_cancel receive_cancel
3514 * send_grant receive_grant
3515 * send_bast receive_bast
3516 * send_lookup receive_lookup
3517 * send_remove receive_remove
3518 *
3519 * send_common_reply
3520 * receive_request_reply send_request_reply
3521 * receive_convert_reply send_convert_reply
3522 * receive_unlock_reply send_unlock_reply
3523 * receive_cancel_reply send_cancel_reply
3524 * receive_lookup_reply send_lookup_reply
3525 */
3526
3527static int _create_message(struct dlm_ls *ls, int mb_len,
3528 int to_nodeid, int mstype,
3529 struct dlm_message **ms_ret,
3530 struct dlm_mhandle **mh_ret)
3531{
3532 struct dlm_message *ms;
3533 struct dlm_mhandle *mh;
3534 char *mb;
3535
3536 /* get_buffer gives us a message handle (mh) that we need to
3537 pass into midcomms_commit and a message buffer (mb) that we
3538 write our data into */
3539
3540 mh = dlm_midcomms_get_mhandle(to_nodeid, mb_len, GFP_NOFS, &mb);
3541 if (!mh)
3542 return -ENOBUFS;
3543
3544 ms = (struct dlm_message *) mb;
3545
3546 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
3547 ms->m_header.u.h_lockspace = ls->ls_global_id;
3548 ms->m_header.h_nodeid = dlm_our_nodeid();
3549 ms->m_header.h_length = mb_len;
3550 ms->m_header.h_cmd = DLM_MSG;
3551
3552 ms->m_type = mstype;
3553
3554 *mh_ret = mh;
3555 *ms_ret = ms;
3556 return 0;
3557}
3558
3559static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3560 int to_nodeid, int mstype,
3561 struct dlm_message **ms_ret,
3562 struct dlm_mhandle **mh_ret)
3563{
3564 int mb_len = sizeof(struct dlm_message);
3565
3566 switch (mstype) {
3567 case DLM_MSG_REQUEST:
3568 case DLM_MSG_LOOKUP:
3569 case DLM_MSG_REMOVE:
3570 mb_len += r->res_length;
3571 break;
3572 case DLM_MSG_CONVERT:
3573 case DLM_MSG_UNLOCK:
3574 case DLM_MSG_REQUEST_REPLY:
3575 case DLM_MSG_CONVERT_REPLY:
3576 case DLM_MSG_GRANT:
3577 if (lkb && lkb->lkb_lvbptr)
3578 mb_len += r->res_ls->ls_lvblen;
3579 break;
3580 }
3581
3582 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3583 ms_ret, mh_ret);
3584}
3585
3586/* further lowcomms enhancements or alternate implementations may make
3587 the return value from this function useful at some point */
3588
3589static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
3590{
3591 dlm_message_out(ms);
3592 dlm_midcomms_commit_mhandle(mh);
3593 return 0;
3594}
3595
3596static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3597 struct dlm_message *ms)
3598{
3599 ms->m_nodeid = lkb->lkb_nodeid;
3600 ms->m_pid = lkb->lkb_ownpid;
3601 ms->m_lkid = lkb->lkb_id;
3602 ms->m_remid = lkb->lkb_remid;
3603 ms->m_exflags = lkb->lkb_exflags;
3604 ms->m_sbflags = lkb->lkb_sbflags;
3605 ms->m_flags = lkb->lkb_flags;
3606 ms->m_lvbseq = lkb->lkb_lvbseq;
3607 ms->m_status = lkb->lkb_status;
3608 ms->m_grmode = lkb->lkb_grmode;
3609 ms->m_rqmode = lkb->lkb_rqmode;
3610 ms->m_hash = r->res_hash;
3611
3612 /* m_result and m_bastmode are set from function args,
3613 not from lkb fields */
3614
3615 if (lkb->lkb_bastfn)
3616 ms->m_asts |= DLM_CB_BAST;
3617 if (lkb->lkb_astfn)
3618 ms->m_asts |= DLM_CB_CAST;
3619
3620 /* compare with switch in create_message; send_remove() doesn't
3621 use send_args() */
3622
3623 switch (ms->m_type) {
3624 case DLM_MSG_REQUEST:
3625 case DLM_MSG_LOOKUP:
3626 memcpy(ms->m_extra, r->res_name, r->res_length);
3627 break;
3628 case DLM_MSG_CONVERT:
3629 case DLM_MSG_UNLOCK:
3630 case DLM_MSG_REQUEST_REPLY:
3631 case DLM_MSG_CONVERT_REPLY:
3632 case DLM_MSG_GRANT:
3633 if (!lkb->lkb_lvbptr)
3634 break;
3635 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
3636 break;
3637 }
3638}
3639
3640static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3641{
3642 struct dlm_message *ms;
3643 struct dlm_mhandle *mh;
3644 int to_nodeid, error;
3645
3646 to_nodeid = r->res_nodeid;
3647
3648 error = add_to_waiters(lkb, mstype, to_nodeid);
3649 if (error)
3650 return error;
3651
3652 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3653 if (error)
3654 goto fail;
3655
3656 send_args(r, lkb, ms);
3657
3658 error = send_message(mh, ms);
3659 if (error)
3660 goto fail;
3661 return 0;
3662
3663 fail:
3664 remove_from_waiters(lkb, msg_reply_type(mstype));
3665 return error;
3666}
3667
3668static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3669{
3670 return send_common(r, lkb, DLM_MSG_REQUEST);
3671}
3672
3673static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3674{
3675 int error;
3676
3677 error = send_common(r, lkb, DLM_MSG_CONVERT);
3678
3679 /* down conversions go without a reply from the master */
3680 if (!error && down_conversion(lkb)) {
3681 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
3682 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
3683 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
3684 r->res_ls->ls_stub_ms.m_result = 0;
3685 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3686 }
3687
3688 return error;
3689}
3690
3691/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3692 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3693 that the master is still correct. */
3694
3695static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3696{
3697 return send_common(r, lkb, DLM_MSG_UNLOCK);
3698}
3699
3700static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3701{
3702 return send_common(r, lkb, DLM_MSG_CANCEL);
3703}
3704
3705static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3706{
3707 struct dlm_message *ms;
3708 struct dlm_mhandle *mh;
3709 int to_nodeid, error;
3710
3711 to_nodeid = lkb->lkb_nodeid;
3712
3713 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3714 if (error)
3715 goto out;
3716
3717 send_args(r, lkb, ms);
3718
3719 ms->m_result = 0;
3720
3721 error = send_message(mh, ms);
3722 out:
3723 return error;
3724}
3725
3726static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3727{
3728 struct dlm_message *ms;
3729 struct dlm_mhandle *mh;
3730 int to_nodeid, error;
3731
3732 to_nodeid = lkb->lkb_nodeid;
3733
3734 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3735 if (error)
3736 goto out;
3737
3738 send_args(r, lkb, ms);
3739
3740 ms->m_bastmode = mode;
3741
3742 error = send_message(mh, ms);
3743 out:
3744 return error;
3745}
3746
3747static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3748{
3749 struct dlm_message *ms;
3750 struct dlm_mhandle *mh;
3751 int to_nodeid, error;
3752
3753 to_nodeid = dlm_dir_nodeid(r);
3754
3755 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
3756 if (error)
3757 return error;
3758
3759 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3760 if (error)
3761 goto fail;
3762
3763 send_args(r, lkb, ms);
3764
3765 error = send_message(mh, ms);
3766 if (error)
3767 goto fail;
3768 return 0;
3769
3770 fail:
3771 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3772 return error;
3773}
3774
3775static int send_remove(struct dlm_rsb *r)
3776{
3777 struct dlm_message *ms;
3778 struct dlm_mhandle *mh;
3779 int to_nodeid, error;
3780
3781 to_nodeid = dlm_dir_nodeid(r);
3782
3783 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3784 if (error)
3785 goto out;
3786
3787 memcpy(ms->m_extra, r->res_name, r->res_length);
3788 ms->m_hash = r->res_hash;
3789
3790 error = send_message(mh, ms);
3791 out:
3792 return error;
3793}
3794
3795static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3796 int mstype, int rv)
3797{
3798 struct dlm_message *ms;
3799 struct dlm_mhandle *mh;
3800 int to_nodeid, error;
3801
3802 to_nodeid = lkb->lkb_nodeid;
3803
3804 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3805 if (error)
3806 goto out;
3807
3808 send_args(r, lkb, ms);
3809
3810 ms->m_result = rv;
3811
3812 error = send_message(mh, ms);
3813 out:
3814 return error;
3815}
3816
3817static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3818{
3819 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3820}
3821
3822static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3823{
3824 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3825}
3826
3827static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3828{
3829 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3830}
3831
3832static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3833{
3834 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3835}
3836
3837static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3838 int ret_nodeid, int rv)
3839{
3840 struct dlm_rsb *r = &ls->ls_stub_rsb;
3841 struct dlm_message *ms;
3842 struct dlm_mhandle *mh;
3843 int error, nodeid = ms_in->m_header.h_nodeid;
3844
3845 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3846 if (error)
3847 goto out;
3848
3849 ms->m_lkid = ms_in->m_lkid;
3850 ms->m_result = rv;
3851 ms->m_nodeid = ret_nodeid;
3852
3853 error = send_message(mh, ms);
3854 out:
3855 return error;
3856}
3857
3858/* which args we save from a received message depends heavily on the type
3859 of message, unlike the send side where we can safely send everything about
3860 the lkb for any type of message */
3861
3862static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3863{
3864 lkb->lkb_exflags = ms->m_exflags;
3865 lkb->lkb_sbflags = ms->m_sbflags;
3866 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3867 (ms->m_flags & 0x0000FFFF);
3868}
3869
3870static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3871{
3872 if (ms->m_flags == DLM_IFL_STUB_MS)
3873 return;
3874
3875 lkb->lkb_sbflags = ms->m_sbflags;
3876 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3877 (ms->m_flags & 0x0000FFFF);
3878}
3879
3880static int receive_extralen(struct dlm_message *ms)
3881{
3882 return (ms->m_header.h_length - sizeof(struct dlm_message));
3883}
3884
3885static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3886 struct dlm_message *ms)
3887{
3888 int len;
3889
3890 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3891 if (!lkb->lkb_lvbptr)
3892 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3893 if (!lkb->lkb_lvbptr)
3894 return -ENOMEM;
3895 len = receive_extralen(ms);
3896 if (len > ls->ls_lvblen)
3897 len = ls->ls_lvblen;
3898 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3899 }
3900 return 0;
3901}
3902
3903static void fake_bastfn(void *astparam, int mode)
3904{
3905 log_print("fake_bastfn should not be called");
3906}
3907
3908static void fake_astfn(void *astparam)
3909{
3910 log_print("fake_astfn should not be called");
3911}
3912
3913static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3914 struct dlm_message *ms)
3915{
3916 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3917 lkb->lkb_ownpid = ms->m_pid;
3918 lkb->lkb_remid = ms->m_lkid;
3919 lkb->lkb_grmode = DLM_LOCK_IV;
3920 lkb->lkb_rqmode = ms->m_rqmode;
3921
3922 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3923 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
3924
3925 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3926 /* lkb was just created so there won't be an lvb yet */
3927 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
3928 if (!lkb->lkb_lvbptr)
3929 return -ENOMEM;
3930 }
3931
3932 return 0;
3933}
3934
3935static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3936 struct dlm_message *ms)
3937{
3938 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3939 return -EBUSY;
3940
3941 if (receive_lvb(ls, lkb, ms))
3942 return -ENOMEM;
3943
3944 lkb->lkb_rqmode = ms->m_rqmode;
3945 lkb->lkb_lvbseq = ms->m_lvbseq;
3946
3947 return 0;
3948}
3949
3950static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3951 struct dlm_message *ms)
3952{
3953 if (receive_lvb(ls, lkb, ms))
3954 return -ENOMEM;
3955 return 0;
3956}
3957
3958/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3959 uses to send a reply and that the remote end uses to process the reply. */
3960
3961static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3962{
3963 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3964 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3965 lkb->lkb_remid = ms->m_lkid;
3966}
3967
3968/* This is called after the rsb is locked so that we can safely inspect
3969 fields in the lkb. */
3970
3971static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3972{
3973 int from = ms->m_header.h_nodeid;
3974 int error = 0;
3975
3976 switch (ms->m_type) {
3977 case DLM_MSG_CONVERT:
3978 case DLM_MSG_UNLOCK:
3979 case DLM_MSG_CANCEL:
3980 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3981 error = -EINVAL;
3982 break;
3983
3984 case DLM_MSG_CONVERT_REPLY:
3985 case DLM_MSG_UNLOCK_REPLY:
3986 case DLM_MSG_CANCEL_REPLY:
3987 case DLM_MSG_GRANT:
3988 case DLM_MSG_BAST:
3989 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3990 error = -EINVAL;
3991 break;
3992
3993 case DLM_MSG_REQUEST_REPLY:
3994 if (!is_process_copy(lkb))
3995 error = -EINVAL;
3996 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3997 error = -EINVAL;
3998 break;
3999
4000 default:
4001 error = -EINVAL;
4002 }
4003
4004 if (error)
4005 log_error(lkb->lkb_resource->res_ls,
4006 "ignore invalid message %d from %d %x %x %x %d",
4007 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
4008 lkb->lkb_flags, lkb->lkb_nodeid);
4009 return error;
4010}
4011
4012static void send_repeat_remove(struct dlm_ls *ls, char *ms_name, int len)
4013{
4014 char name[DLM_RESNAME_MAXLEN + 1];
4015 struct dlm_message *ms;
4016 struct dlm_mhandle *mh;
4017 struct dlm_rsb *r;
4018 uint32_t hash, b;
4019 int rv, dir_nodeid;
4020
4021 memset(name, 0, sizeof(name));
4022 memcpy(name, ms_name, len);
4023
4024 hash = jhash(name, len, 0);
4025 b = hash & (ls->ls_rsbtbl_size - 1);
4026
4027 dir_nodeid = dlm_hash2nodeid(ls, hash);
4028
4029 log_error(ls, "send_repeat_remove dir %d %s", dir_nodeid, name);
4030
4031 spin_lock(&ls->ls_rsbtbl[b].lock);
4032 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4033 if (!rv) {
4034 spin_unlock(&ls->ls_rsbtbl[b].lock);
4035 log_error(ls, "repeat_remove on keep %s", name);
4036 return;
4037 }
4038
4039 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4040 if (!rv) {
4041 spin_unlock(&ls->ls_rsbtbl[b].lock);
4042 log_error(ls, "repeat_remove on toss %s", name);
4043 return;
4044 }
4045
4046 /* use ls->remove_name2 to avoid conflict with shrink? */
4047
4048 spin_lock(&ls->ls_remove_spin);
4049 ls->ls_remove_len = len;
4050 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
4051 spin_unlock(&ls->ls_remove_spin);
4052 spin_unlock(&ls->ls_rsbtbl[b].lock);
4053
4054 rv = _create_message(ls, sizeof(struct dlm_message) + len,
4055 dir_nodeid, DLM_MSG_REMOVE, &ms, &mh);
4056 if (rv)
4057 return;
4058
4059 memcpy(ms->m_extra, name, len);
4060 ms->m_hash = hash;
4061
4062 send_message(mh, ms);
4063
4064 spin_lock(&ls->ls_remove_spin);
4065 ls->ls_remove_len = 0;
4066 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
4067 spin_unlock(&ls->ls_remove_spin);
4068}
4069
4070static int receive_request(struct dlm_ls *ls, struct dlm_message *ms)
4071{
4072 struct dlm_lkb *lkb;
4073 struct dlm_rsb *r;
4074 int from_nodeid;
4075 int error, namelen = 0;
4076
4077 from_nodeid = ms->m_header.h_nodeid;
4078
4079 error = create_lkb(ls, &lkb);
4080 if (error)
4081 goto fail;
4082
4083 receive_flags(lkb, ms);
4084 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4085 error = receive_request_args(ls, lkb, ms);
4086 if (error) {
4087 __put_lkb(ls, lkb);
4088 goto fail;
4089 }
4090
4091 /* The dir node is the authority on whether we are the master
4092 for this rsb or not, so if the master sends us a request, we should
4093 recreate the rsb if we've destroyed it. This race happens when we
4094 send a remove message to the dir node at the same time that the dir
4095 node sends us a request for the rsb. */
4096
4097 namelen = receive_extralen(ms);
4098
4099 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
4100 R_RECEIVE_REQUEST, &r);
4101 if (error) {
4102 __put_lkb(ls, lkb);
4103 goto fail;
4104 }
4105
4106 lock_rsb(r);
4107
4108 if (r->res_master_nodeid != dlm_our_nodeid()) {
4109 error = validate_master_nodeid(ls, r, from_nodeid);
4110 if (error) {
4111 unlock_rsb(r);
4112 put_rsb(r);
4113 __put_lkb(ls, lkb);
4114 goto fail;
4115 }
4116 }
4117
4118 attach_lkb(r, lkb);
4119 error = do_request(r, lkb);
4120 send_request_reply(r, lkb, error);
4121 do_request_effects(r, lkb, error);
4122
4123 unlock_rsb(r);
4124 put_rsb(r);
4125
4126 if (error == -EINPROGRESS)
4127 error = 0;
4128 if (error)
4129 dlm_put_lkb(lkb);
4130 return 0;
4131
4132 fail:
4133 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
4134 and do this receive_request again from process_lookup_list once
4135 we get the lookup reply. This would avoid a many repeated
4136 ENOTBLK request failures when the lookup reply designating us
4137 as master is delayed. */
4138
4139 /* We could repeatedly return -EBADR here if our send_remove() is
4140 delayed in being sent/arriving/being processed on the dir node.
4141 Another node would repeatedly lookup up the master, and the dir
4142 node would continue returning our nodeid until our send_remove
4143 took effect.
4144
4145 We send another remove message in case our previous send_remove
4146 was lost/ignored/missed somehow. */
4147
4148 if (error != -ENOTBLK) {
4149 log_limit(ls, "receive_request %x from %d %d",
4150 ms->m_lkid, from_nodeid, error);
4151 }
4152
4153 if (namelen && error == -EBADR) {
4154 send_repeat_remove(ls, ms->m_extra, namelen);
4155 msleep(1000);
4156 }
4157
4158 setup_stub_lkb(ls, ms);
4159 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4160 return error;
4161}
4162
4163static int receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
4164{
4165 struct dlm_lkb *lkb;
4166 struct dlm_rsb *r;
4167 int error, reply = 1;
4168
4169 error = find_lkb(ls, ms->m_remid, &lkb);
4170 if (error)
4171 goto fail;
4172
4173 if (lkb->lkb_remid != ms->m_lkid) {
4174 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
4175 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
4176 (unsigned long long)lkb->lkb_recover_seq,
4177 ms->m_header.h_nodeid, ms->m_lkid);
4178 error = -ENOENT;
4179 dlm_put_lkb(lkb);
4180 goto fail;
4181 }
4182
4183 r = lkb->lkb_resource;
4184
4185 hold_rsb(r);
4186 lock_rsb(r);
4187
4188 error = validate_message(lkb, ms);
4189 if (error)
4190 goto out;
4191
4192 receive_flags(lkb, ms);
4193
4194 error = receive_convert_args(ls, lkb, ms);
4195 if (error) {
4196 send_convert_reply(r, lkb, error);
4197 goto out;
4198 }
4199
4200 reply = !down_conversion(lkb);
4201
4202 error = do_convert(r, lkb);
4203 if (reply)
4204 send_convert_reply(r, lkb, error);
4205 do_convert_effects(r, lkb, error);
4206 out:
4207 unlock_rsb(r);
4208 put_rsb(r);
4209 dlm_put_lkb(lkb);
4210 return 0;
4211
4212 fail:
4213 setup_stub_lkb(ls, ms);
4214 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4215 return error;
4216}
4217
4218static int receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
4219{
4220 struct dlm_lkb *lkb;
4221 struct dlm_rsb *r;
4222 int error;
4223
4224 error = find_lkb(ls, ms->m_remid, &lkb);
4225 if (error)
4226 goto fail;
4227
4228 if (lkb->lkb_remid != ms->m_lkid) {
4229 log_error(ls, "receive_unlock %x remid %x remote %d %x",
4230 lkb->lkb_id, lkb->lkb_remid,
4231 ms->m_header.h_nodeid, ms->m_lkid);
4232 error = -ENOENT;
4233 dlm_put_lkb(lkb);
4234 goto fail;
4235 }
4236
4237 r = lkb->lkb_resource;
4238
4239 hold_rsb(r);
4240 lock_rsb(r);
4241
4242 error = validate_message(lkb, ms);
4243 if (error)
4244 goto out;
4245
4246 receive_flags(lkb, ms);
4247
4248 error = receive_unlock_args(ls, lkb, ms);
4249 if (error) {
4250 send_unlock_reply(r, lkb, error);
4251 goto out;
4252 }
4253
4254 error = do_unlock(r, lkb);
4255 send_unlock_reply(r, lkb, error);
4256 do_unlock_effects(r, lkb, error);
4257 out:
4258 unlock_rsb(r);
4259 put_rsb(r);
4260 dlm_put_lkb(lkb);
4261 return 0;
4262
4263 fail:
4264 setup_stub_lkb(ls, ms);
4265 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4266 return error;
4267}
4268
4269static int receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
4270{
4271 struct dlm_lkb *lkb;
4272 struct dlm_rsb *r;
4273 int error;
4274
4275 error = find_lkb(ls, ms->m_remid, &lkb);
4276 if (error)
4277 goto fail;
4278
4279 receive_flags(lkb, ms);
4280
4281 r = lkb->lkb_resource;
4282
4283 hold_rsb(r);
4284 lock_rsb(r);
4285
4286 error = validate_message(lkb, ms);
4287 if (error)
4288 goto out;
4289
4290 error = do_cancel(r, lkb);
4291 send_cancel_reply(r, lkb, error);
4292 do_cancel_effects(r, lkb, error);
4293 out:
4294 unlock_rsb(r);
4295 put_rsb(r);
4296 dlm_put_lkb(lkb);
4297 return 0;
4298
4299 fail:
4300 setup_stub_lkb(ls, ms);
4301 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
4302 return error;
4303}
4304
4305static int receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
4306{
4307 struct dlm_lkb *lkb;
4308 struct dlm_rsb *r;
4309 int error;
4310
4311 error = find_lkb(ls, ms->m_remid, &lkb);
4312 if (error)
4313 return error;
4314
4315 r = lkb->lkb_resource;
4316
4317 hold_rsb(r);
4318 lock_rsb(r);
4319
4320 error = validate_message(lkb, ms);
4321 if (error)
4322 goto out;
4323
4324 receive_flags_reply(lkb, ms);
4325 if (is_altmode(lkb))
4326 munge_altmode(lkb, ms);
4327 grant_lock_pc(r, lkb, ms);
4328 queue_cast(r, lkb, 0);
4329 out:
4330 unlock_rsb(r);
4331 put_rsb(r);
4332 dlm_put_lkb(lkb);
4333 return 0;
4334}
4335
4336static int receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
4337{
4338 struct dlm_lkb *lkb;
4339 struct dlm_rsb *r;
4340 int error;
4341
4342 error = find_lkb(ls, ms->m_remid, &lkb);
4343 if (error)
4344 return error;
4345
4346 r = lkb->lkb_resource;
4347
4348 hold_rsb(r);
4349 lock_rsb(r);
4350
4351 error = validate_message(lkb, ms);
4352 if (error)
4353 goto out;
4354
4355 queue_bast(r, lkb, ms->m_bastmode);
4356 lkb->lkb_highbast = ms->m_bastmode;
4357 out:
4358 unlock_rsb(r);
4359 put_rsb(r);
4360 dlm_put_lkb(lkb);
4361 return 0;
4362}
4363
4364static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
4365{
4366 int len, error, ret_nodeid, from_nodeid, our_nodeid;
4367
4368 from_nodeid = ms->m_header.h_nodeid;
4369 our_nodeid = dlm_our_nodeid();
4370
4371 len = receive_extralen(ms);
4372
4373 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4374 &ret_nodeid, NULL);
4375
4376 /* Optimization: we're master so treat lookup as a request */
4377 if (!error && ret_nodeid == our_nodeid) {
4378 receive_request(ls, ms);
4379 return;
4380 }
4381 send_lookup_reply(ls, ms, ret_nodeid, error);
4382}
4383
4384static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
4385{
4386 char name[DLM_RESNAME_MAXLEN+1];
4387 struct dlm_rsb *r;
4388 uint32_t hash, b;
4389 int rv, len, dir_nodeid, from_nodeid;
4390
4391 from_nodeid = ms->m_header.h_nodeid;
4392
4393 len = receive_extralen(ms);
4394
4395 if (len > DLM_RESNAME_MAXLEN) {
4396 log_error(ls, "receive_remove from %d bad len %d",
4397 from_nodeid, len);
4398 return;
4399 }
4400
4401 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
4402 if (dir_nodeid != dlm_our_nodeid()) {
4403 log_error(ls, "receive_remove from %d bad nodeid %d",
4404 from_nodeid, dir_nodeid);
4405 return;
4406 }
4407
4408 /* Look for name on rsbtbl.toss, if it's there, kill it.
4409 If it's on rsbtbl.keep, it's being used, and we should ignore this
4410 message. This is an expected race between the dir node sending a
4411 request to the master node at the same time as the master node sends
4412 a remove to the dir node. The resolution to that race is for the
4413 dir node to ignore the remove message, and the master node to
4414 recreate the master rsb when it gets a request from the dir node for
4415 an rsb it doesn't have. */
4416
4417 memset(name, 0, sizeof(name));
4418 memcpy(name, ms->m_extra, len);
4419
4420 hash = jhash(name, len, 0);
4421 b = hash & (ls->ls_rsbtbl_size - 1);
4422
4423 spin_lock(&ls->ls_rsbtbl[b].lock);
4424
4425 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4426 if (rv) {
4427 /* verify the rsb is on keep list per comment above */
4428 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4429 if (rv) {
4430 /* should not happen */
4431 log_error(ls, "receive_remove from %d not found %s",
4432 from_nodeid, name);
4433 spin_unlock(&ls->ls_rsbtbl[b].lock);
4434 return;
4435 }
4436 if (r->res_master_nodeid != from_nodeid) {
4437 /* should not happen */
4438 log_error(ls, "receive_remove keep from %d master %d",
4439 from_nodeid, r->res_master_nodeid);
4440 dlm_print_rsb(r);
4441 spin_unlock(&ls->ls_rsbtbl[b].lock);
4442 return;
4443 }
4444
4445 log_debug(ls, "receive_remove from %d master %d first %x %s",
4446 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4447 name);
4448 spin_unlock(&ls->ls_rsbtbl[b].lock);
4449 return;
4450 }
4451
4452 if (r->res_master_nodeid != from_nodeid) {
4453 log_error(ls, "receive_remove toss from %d master %d",
4454 from_nodeid, r->res_master_nodeid);
4455 dlm_print_rsb(r);
4456 spin_unlock(&ls->ls_rsbtbl[b].lock);
4457 return;
4458 }
4459
4460 if (kref_put(&r->res_ref, kill_rsb)) {
4461 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4462 spin_unlock(&ls->ls_rsbtbl[b].lock);
4463 dlm_free_rsb(r);
4464 } else {
4465 log_error(ls, "receive_remove from %d rsb ref error",
4466 from_nodeid);
4467 dlm_print_rsb(r);
4468 spin_unlock(&ls->ls_rsbtbl[b].lock);
4469 }
4470}
4471
4472static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
4473{
4474 do_purge(ls, ms->m_nodeid, ms->m_pid);
4475}
4476
4477static int receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
4478{
4479 struct dlm_lkb *lkb;
4480 struct dlm_rsb *r;
4481 int error, mstype, result;
4482 int from_nodeid = ms->m_header.h_nodeid;
4483
4484 error = find_lkb(ls, ms->m_remid, &lkb);
4485 if (error)
4486 return error;
4487
4488 r = lkb->lkb_resource;
4489 hold_rsb(r);
4490 lock_rsb(r);
4491
4492 error = validate_message(lkb, ms);
4493 if (error)
4494 goto out;
4495
4496 mstype = lkb->lkb_wait_type;
4497 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4498 if (error) {
4499 log_error(ls, "receive_request_reply %x remote %d %x result %d",
4500 lkb->lkb_id, from_nodeid, ms->m_lkid, ms->m_result);
4501 dlm_dump_rsb(r);
4502 goto out;
4503 }
4504
4505 /* Optimization: the dir node was also the master, so it took our
4506 lookup as a request and sent request reply instead of lookup reply */
4507 if (mstype == DLM_MSG_LOOKUP) {
4508 r->res_master_nodeid = from_nodeid;
4509 r->res_nodeid = from_nodeid;
4510 lkb->lkb_nodeid = from_nodeid;
4511 }
4512
4513 /* this is the value returned from do_request() on the master */
4514 result = ms->m_result;
4515
4516 switch (result) {
4517 case -EAGAIN:
4518 /* request would block (be queued) on remote master */
4519 queue_cast(r, lkb, -EAGAIN);
4520 confirm_master(r, -EAGAIN);
4521 unhold_lkb(lkb); /* undoes create_lkb() */
4522 break;
4523
4524 case -EINPROGRESS:
4525 case 0:
4526 /* request was queued or granted on remote master */
4527 receive_flags_reply(lkb, ms);
4528 lkb->lkb_remid = ms->m_lkid;
4529 if (is_altmode(lkb))
4530 munge_altmode(lkb, ms);
4531 if (result) {
4532 add_lkb(r, lkb, DLM_LKSTS_WAITING);
4533 add_timeout(lkb);
4534 } else {
4535 grant_lock_pc(r, lkb, ms);
4536 queue_cast(r, lkb, 0);
4537 }
4538 confirm_master(r, result);
4539 break;
4540
4541 case -EBADR:
4542 case -ENOTBLK:
4543 /* find_rsb failed to find rsb or rsb wasn't master */
4544 log_limit(ls, "receive_request_reply %x from %d %d "
4545 "master %d dir %d first %x %s", lkb->lkb_id,
4546 from_nodeid, result, r->res_master_nodeid,
4547 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4548
4549 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4550 r->res_master_nodeid != dlm_our_nodeid()) {
4551 /* cause _request_lock->set_master->send_lookup */
4552 r->res_master_nodeid = 0;
4553 r->res_nodeid = -1;
4554 lkb->lkb_nodeid = -1;
4555 }
4556
4557 if (is_overlap(lkb)) {
4558 /* we'll ignore error in cancel/unlock reply */
4559 queue_cast_overlap(r, lkb);
4560 confirm_master(r, result);
4561 unhold_lkb(lkb); /* undoes create_lkb() */
4562 } else {
4563 _request_lock(r, lkb);
4564
4565 if (r->res_master_nodeid == dlm_our_nodeid())
4566 confirm_master(r, 0);
4567 }
4568 break;
4569
4570 default:
4571 log_error(ls, "receive_request_reply %x error %d",
4572 lkb->lkb_id, result);
4573 }
4574
4575 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
4576 log_debug(ls, "receive_request_reply %x result %d unlock",
4577 lkb->lkb_id, result);
4578 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4579 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4580 send_unlock(r, lkb);
4581 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
4582 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4583 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4584 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4585 send_cancel(r, lkb);
4586 } else {
4587 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4588 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4589 }
4590 out:
4591 unlock_rsb(r);
4592 put_rsb(r);
4593 dlm_put_lkb(lkb);
4594 return 0;
4595}
4596
4597static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4598 struct dlm_message *ms)
4599{
4600 /* this is the value returned from do_convert() on the master */
4601 switch (ms->m_result) {
4602 case -EAGAIN:
4603 /* convert would block (be queued) on remote master */
4604 queue_cast(r, lkb, -EAGAIN);
4605 break;
4606
4607 case -EDEADLK:
4608 receive_flags_reply(lkb, ms);
4609 revert_lock_pc(r, lkb);
4610 queue_cast(r, lkb, -EDEADLK);
4611 break;
4612
4613 case -EINPROGRESS:
4614 /* convert was queued on remote master */
4615 receive_flags_reply(lkb, ms);
4616 if (is_demoted(lkb))
4617 munge_demoted(lkb);
4618 del_lkb(r, lkb);
4619 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
4620 add_timeout(lkb);
4621 break;
4622
4623 case 0:
4624 /* convert was granted on remote master */
4625 receive_flags_reply(lkb, ms);
4626 if (is_demoted(lkb))
4627 munge_demoted(lkb);
4628 grant_lock_pc(r, lkb, ms);
4629 queue_cast(r, lkb, 0);
4630 break;
4631
4632 default:
4633 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4634 lkb->lkb_id, ms->m_header.h_nodeid, ms->m_lkid,
4635 ms->m_result);
4636 dlm_print_rsb(r);
4637 dlm_print_lkb(lkb);
4638 }
4639}
4640
4641static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4642{
4643 struct dlm_rsb *r = lkb->lkb_resource;
4644 int error;
4645
4646 hold_rsb(r);
4647 lock_rsb(r);
4648
4649 error = validate_message(lkb, ms);
4650 if (error)
4651 goto out;
4652
4653 /* stub reply can happen with waiters_mutex held */
4654 error = remove_from_waiters_ms(lkb, ms);
4655 if (error)
4656 goto out;
4657
4658 __receive_convert_reply(r, lkb, ms);
4659 out:
4660 unlock_rsb(r);
4661 put_rsb(r);
4662}
4663
4664static int receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
4665{
4666 struct dlm_lkb *lkb;
4667 int error;
4668
4669 error = find_lkb(ls, ms->m_remid, &lkb);
4670 if (error)
4671 return error;
4672
4673 _receive_convert_reply(lkb, ms);
4674 dlm_put_lkb(lkb);
4675 return 0;
4676}
4677
4678static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4679{
4680 struct dlm_rsb *r = lkb->lkb_resource;
4681 int error;
4682
4683 hold_rsb(r);
4684 lock_rsb(r);
4685
4686 error = validate_message(lkb, ms);
4687 if (error)
4688 goto out;
4689
4690 /* stub reply can happen with waiters_mutex held */
4691 error = remove_from_waiters_ms(lkb, ms);
4692 if (error)
4693 goto out;
4694
4695 /* this is the value returned from do_unlock() on the master */
4696
4697 switch (ms->m_result) {
4698 case -DLM_EUNLOCK:
4699 receive_flags_reply(lkb, ms);
4700 remove_lock_pc(r, lkb);
4701 queue_cast(r, lkb, -DLM_EUNLOCK);
4702 break;
4703 case -ENOENT:
4704 break;
4705 default:
4706 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4707 lkb->lkb_id, ms->m_result);
4708 }
4709 out:
4710 unlock_rsb(r);
4711 put_rsb(r);
4712}
4713
4714static int receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
4715{
4716 struct dlm_lkb *lkb;
4717 int error;
4718
4719 error = find_lkb(ls, ms->m_remid, &lkb);
4720 if (error)
4721 return error;
4722
4723 _receive_unlock_reply(lkb, ms);
4724 dlm_put_lkb(lkb);
4725 return 0;
4726}
4727
4728static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4729{
4730 struct dlm_rsb *r = lkb->lkb_resource;
4731 int error;
4732
4733 hold_rsb(r);
4734 lock_rsb(r);
4735
4736 error = validate_message(lkb, ms);
4737 if (error)
4738 goto out;
4739
4740 /* stub reply can happen with waiters_mutex held */
4741 error = remove_from_waiters_ms(lkb, ms);
4742 if (error)
4743 goto out;
4744
4745 /* this is the value returned from do_cancel() on the master */
4746
4747 switch (ms->m_result) {
4748 case -DLM_ECANCEL:
4749 receive_flags_reply(lkb, ms);
4750 revert_lock_pc(r, lkb);
4751 queue_cast(r, lkb, -DLM_ECANCEL);
4752 break;
4753 case 0:
4754 break;
4755 default:
4756 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4757 lkb->lkb_id, ms->m_result);
4758 }
4759 out:
4760 unlock_rsb(r);
4761 put_rsb(r);
4762}
4763
4764static int receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
4765{
4766 struct dlm_lkb *lkb;
4767 int error;
4768
4769 error = find_lkb(ls, ms->m_remid, &lkb);
4770 if (error)
4771 return error;
4772
4773 _receive_cancel_reply(lkb, ms);
4774 dlm_put_lkb(lkb);
4775 return 0;
4776}
4777
4778static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
4779{
4780 struct dlm_lkb *lkb;
4781 struct dlm_rsb *r;
4782 int error, ret_nodeid;
4783 int do_lookup_list = 0;
4784
4785 error = find_lkb(ls, ms->m_lkid, &lkb);
4786 if (error) {
4787 log_error(ls, "receive_lookup_reply no lkid %x", ms->m_lkid);
4788 return;
4789 }
4790
4791 /* ms->m_result is the value returned by dlm_master_lookup on dir node
4792 FIXME: will a non-zero error ever be returned? */
4793
4794 r = lkb->lkb_resource;
4795 hold_rsb(r);
4796 lock_rsb(r);
4797
4798 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4799 if (error)
4800 goto out;
4801
4802 ret_nodeid = ms->m_nodeid;
4803
4804 /* We sometimes receive a request from the dir node for this
4805 rsb before we've received the dir node's loookup_reply for it.
4806 The request from the dir node implies we're the master, so we set
4807 ourself as master in receive_request_reply, and verify here that
4808 we are indeed the master. */
4809
4810 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4811 /* This should never happen */
4812 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4813 "master %d dir %d our %d first %x %s",
4814 lkb->lkb_id, ms->m_header.h_nodeid, ret_nodeid,
4815 r->res_master_nodeid, r->res_dir_nodeid,
4816 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4817 }
4818
4819 if (ret_nodeid == dlm_our_nodeid()) {
4820 r->res_master_nodeid = ret_nodeid;
4821 r->res_nodeid = 0;
4822 do_lookup_list = 1;
4823 r->res_first_lkid = 0;
4824 } else if (ret_nodeid == -1) {
4825 /* the remote node doesn't believe it's the dir node */
4826 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4827 lkb->lkb_id, ms->m_header.h_nodeid);
4828 r->res_master_nodeid = 0;
4829 r->res_nodeid = -1;
4830 lkb->lkb_nodeid = -1;
4831 } else {
4832 /* set_master() will set lkb_nodeid from r */
4833 r->res_master_nodeid = ret_nodeid;
4834 r->res_nodeid = ret_nodeid;
4835 }
4836
4837 if (is_overlap(lkb)) {
4838 log_debug(ls, "receive_lookup_reply %x unlock %x",
4839 lkb->lkb_id, lkb->lkb_flags);
4840 queue_cast_overlap(r, lkb);
4841 unhold_lkb(lkb); /* undoes create_lkb() */
4842 goto out_list;
4843 }
4844
4845 _request_lock(r, lkb);
4846
4847 out_list:
4848 if (do_lookup_list)
4849 process_lookup_list(r);
4850 out:
4851 unlock_rsb(r);
4852 put_rsb(r);
4853 dlm_put_lkb(lkb);
4854}
4855
4856static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4857 uint32_t saved_seq)
4858{
4859 int error = 0, noent = 0;
4860
4861 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
4862 log_limit(ls, "receive %d from non-member %d %x %x %d",
4863 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4864 ms->m_remid, ms->m_result);
4865 return;
4866 }
4867
4868 switch (ms->m_type) {
4869
4870 /* messages sent to a master node */
4871
4872 case DLM_MSG_REQUEST:
4873 error = receive_request(ls, ms);
4874 break;
4875
4876 case DLM_MSG_CONVERT:
4877 error = receive_convert(ls, ms);
4878 break;
4879
4880 case DLM_MSG_UNLOCK:
4881 error = receive_unlock(ls, ms);
4882 break;
4883
4884 case DLM_MSG_CANCEL:
4885 noent = 1;
4886 error = receive_cancel(ls, ms);
4887 break;
4888
4889 /* messages sent from a master node (replies to above) */
4890
4891 case DLM_MSG_REQUEST_REPLY:
4892 error = receive_request_reply(ls, ms);
4893 break;
4894
4895 case DLM_MSG_CONVERT_REPLY:
4896 error = receive_convert_reply(ls, ms);
4897 break;
4898
4899 case DLM_MSG_UNLOCK_REPLY:
4900 error = receive_unlock_reply(ls, ms);
4901 break;
4902
4903 case DLM_MSG_CANCEL_REPLY:
4904 error = receive_cancel_reply(ls, ms);
4905 break;
4906
4907 /* messages sent from a master node (only two types of async msg) */
4908
4909 case DLM_MSG_GRANT:
4910 noent = 1;
4911 error = receive_grant(ls, ms);
4912 break;
4913
4914 case DLM_MSG_BAST:
4915 noent = 1;
4916 error = receive_bast(ls, ms);
4917 break;
4918
4919 /* messages sent to a dir node */
4920
4921 case DLM_MSG_LOOKUP:
4922 receive_lookup(ls, ms);
4923 break;
4924
4925 case DLM_MSG_REMOVE:
4926 receive_remove(ls, ms);
4927 break;
4928
4929 /* messages sent from a dir node (remove has no reply) */
4930
4931 case DLM_MSG_LOOKUP_REPLY:
4932 receive_lookup_reply(ls, ms);
4933 break;
4934
4935 /* other messages */
4936
4937 case DLM_MSG_PURGE:
4938 receive_purge(ls, ms);
4939 break;
4940
4941 default:
4942 log_error(ls, "unknown message type %d", ms->m_type);
4943 }
4944
4945 /*
4946 * When checking for ENOENT, we're checking the result of
4947 * find_lkb(m_remid):
4948 *
4949 * The lock id referenced in the message wasn't found. This may
4950 * happen in normal usage for the async messages and cancel, so
4951 * only use log_debug for them.
4952 *
4953 * Some errors are expected and normal.
4954 */
4955
4956 if (error == -ENOENT && noent) {
4957 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
4958 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4959 ms->m_lkid, saved_seq);
4960 } else if (error == -ENOENT) {
4961 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
4962 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4963 ms->m_lkid, saved_seq);
4964
4965 if (ms->m_type == DLM_MSG_CONVERT)
4966 dlm_dump_rsb_hash(ls, ms->m_hash);
4967 }
4968
4969 if (error == -EINVAL) {
4970 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4971 "saved_seq %u",
4972 ms->m_type, ms->m_header.h_nodeid,
4973 ms->m_lkid, ms->m_remid, saved_seq);
4974 }
4975}
4976
4977/* If the lockspace is in recovery mode (locking stopped), then normal
4978 messages are saved on the requestqueue for processing after recovery is
4979 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4980 messages off the requestqueue before we process new ones. This occurs right
4981 after recovery completes when we transition from saving all messages on
4982 requestqueue, to processing all the saved messages, to processing new
4983 messages as they arrive. */
4984
4985static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4986 int nodeid)
4987{
4988 if (dlm_locking_stopped(ls)) {
4989 /* If we were a member of this lockspace, left, and rejoined,
4990 other nodes may still be sending us messages from the
4991 lockspace generation before we left. */
4992 if (!ls->ls_generation) {
4993 log_limit(ls, "receive %d from %d ignore old gen",
4994 ms->m_type, nodeid);
4995 return;
4996 }
4997
4998 dlm_add_requestqueue(ls, nodeid, ms);
4999 } else {
5000 dlm_wait_requestqueue(ls);
5001 _receive_message(ls, ms, 0);
5002 }
5003}
5004
5005/* This is called by dlm_recoverd to process messages that were saved on
5006 the requestqueue. */
5007
5008void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
5009 uint32_t saved_seq)
5010{
5011 _receive_message(ls, ms, saved_seq);
5012}
5013
5014/* This is called by the midcomms layer when something is received for
5015 the lockspace. It could be either a MSG (normal message sent as part of
5016 standard locking activity) or an RCOM (recovery message sent as part of
5017 lockspace recovery). */
5018
5019void dlm_receive_buffer(union dlm_packet *p, int nodeid)
5020{
5021 struct dlm_header *hd = &p->header;
5022 struct dlm_ls *ls;
5023 int type = 0;
5024
5025 switch (hd->h_cmd) {
5026 case DLM_MSG:
5027 dlm_message_in(&p->message);
5028 type = p->message.m_type;
5029 break;
5030 case DLM_RCOM:
5031 dlm_rcom_in(&p->rcom);
5032 type = p->rcom.rc_type;
5033 break;
5034 default:
5035 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
5036 return;
5037 }
5038
5039 if (hd->h_nodeid != nodeid) {
5040 log_print("invalid h_nodeid %d from %d lockspace %x",
5041 hd->h_nodeid, nodeid, hd->u.h_lockspace);
5042 return;
5043 }
5044
5045 ls = dlm_find_lockspace_global(hd->u.h_lockspace);
5046 if (!ls) {
5047 if (dlm_config.ci_log_debug) {
5048 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
5049 "%u from %d cmd %d type %d\n",
5050 hd->u.h_lockspace, nodeid, hd->h_cmd, type);
5051 }
5052
5053 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
5054 dlm_send_ls_not_ready(nodeid, &p->rcom);
5055 return;
5056 }
5057
5058 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
5059 be inactive (in this ls) before transitioning to recovery mode */
5060
5061 down_read(&ls->ls_recv_active);
5062 if (hd->h_cmd == DLM_MSG)
5063 dlm_receive_message(ls, &p->message, nodeid);
5064 else
5065 dlm_receive_rcom(ls, &p->rcom, nodeid);
5066 up_read(&ls->ls_recv_active);
5067
5068 dlm_put_lockspace(ls);
5069}
5070
5071static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
5072 struct dlm_message *ms_stub)
5073{
5074 if (middle_conversion(lkb)) {
5075 hold_lkb(lkb);
5076 memset(ms_stub, 0, sizeof(struct dlm_message));
5077 ms_stub->m_flags = DLM_IFL_STUB_MS;
5078 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
5079 ms_stub->m_result = -EINPROGRESS;
5080 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5081 _receive_convert_reply(lkb, ms_stub);
5082
5083 /* Same special case as in receive_rcom_lock_args() */
5084 lkb->lkb_grmode = DLM_LOCK_IV;
5085 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
5086 unhold_lkb(lkb);
5087
5088 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
5089 lkb->lkb_flags |= DLM_IFL_RESEND;
5090 }
5091
5092 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
5093 conversions are async; there's no reply from the remote master */
5094}
5095
5096/* A waiting lkb needs recovery if the master node has failed, or
5097 the master node is changing (only when no directory is used) */
5098
5099static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
5100 int dir_nodeid)
5101{
5102 if (dlm_no_directory(ls))
5103 return 1;
5104
5105 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
5106 return 1;
5107
5108 return 0;
5109}
5110
5111/* Recovery for locks that are waiting for replies from nodes that are now
5112 gone. We can just complete unlocks and cancels by faking a reply from the
5113 dead node. Requests and up-conversions we flag to be resent after
5114 recovery. Down-conversions can just be completed with a fake reply like
5115 unlocks. Conversions between PR and CW need special attention. */
5116
5117void dlm_recover_waiters_pre(struct dlm_ls *ls)
5118{
5119 struct dlm_lkb *lkb, *safe;
5120 struct dlm_message *ms_stub;
5121 int wait_type, stub_unlock_result, stub_cancel_result;
5122 int dir_nodeid;
5123
5124 ms_stub = kmalloc(sizeof(*ms_stub), GFP_KERNEL);
5125 if (!ms_stub)
5126 return;
5127
5128 mutex_lock(&ls->ls_waiters_mutex);
5129
5130 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
5131
5132 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
5133
5134 /* exclude debug messages about unlocks because there can be so
5135 many and they aren't very interesting */
5136
5137 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
5138 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5139 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
5140 lkb->lkb_id,
5141 lkb->lkb_remid,
5142 lkb->lkb_wait_type,
5143 lkb->lkb_resource->res_nodeid,
5144 lkb->lkb_nodeid,
5145 lkb->lkb_wait_nodeid,
5146 dir_nodeid);
5147 }
5148
5149 /* all outstanding lookups, regardless of destination will be
5150 resent after recovery is done */
5151
5152 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
5153 lkb->lkb_flags |= DLM_IFL_RESEND;
5154 continue;
5155 }
5156
5157 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
5158 continue;
5159
5160 wait_type = lkb->lkb_wait_type;
5161 stub_unlock_result = -DLM_EUNLOCK;
5162 stub_cancel_result = -DLM_ECANCEL;
5163
5164 /* Main reply may have been received leaving a zero wait_type,
5165 but a reply for the overlapping op may not have been
5166 received. In that case we need to fake the appropriate
5167 reply for the overlap op. */
5168
5169 if (!wait_type) {
5170 if (is_overlap_cancel(lkb)) {
5171 wait_type = DLM_MSG_CANCEL;
5172 if (lkb->lkb_grmode == DLM_LOCK_IV)
5173 stub_cancel_result = 0;
5174 }
5175 if (is_overlap_unlock(lkb)) {
5176 wait_type = DLM_MSG_UNLOCK;
5177 if (lkb->lkb_grmode == DLM_LOCK_IV)
5178 stub_unlock_result = -ENOENT;
5179 }
5180
5181 log_debug(ls, "rwpre overlap %x %x %d %d %d",
5182 lkb->lkb_id, lkb->lkb_flags, wait_type,
5183 stub_cancel_result, stub_unlock_result);
5184 }
5185
5186 switch (wait_type) {
5187
5188 case DLM_MSG_REQUEST:
5189 lkb->lkb_flags |= DLM_IFL_RESEND;
5190 break;
5191
5192 case DLM_MSG_CONVERT:
5193 recover_convert_waiter(ls, lkb, ms_stub);
5194 break;
5195
5196 case DLM_MSG_UNLOCK:
5197 hold_lkb(lkb);
5198 memset(ms_stub, 0, sizeof(struct dlm_message));
5199 ms_stub->m_flags = DLM_IFL_STUB_MS;
5200 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
5201 ms_stub->m_result = stub_unlock_result;
5202 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5203 _receive_unlock_reply(lkb, ms_stub);
5204 dlm_put_lkb(lkb);
5205 break;
5206
5207 case DLM_MSG_CANCEL:
5208 hold_lkb(lkb);
5209 memset(ms_stub, 0, sizeof(struct dlm_message));
5210 ms_stub->m_flags = DLM_IFL_STUB_MS;
5211 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
5212 ms_stub->m_result = stub_cancel_result;
5213 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5214 _receive_cancel_reply(lkb, ms_stub);
5215 dlm_put_lkb(lkb);
5216 break;
5217
5218 default:
5219 log_error(ls, "invalid lkb wait_type %d %d",
5220 lkb->lkb_wait_type, wait_type);
5221 }
5222 schedule();
5223 }
5224 mutex_unlock(&ls->ls_waiters_mutex);
5225 kfree(ms_stub);
5226}
5227
5228static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
5229{
5230 struct dlm_lkb *lkb;
5231 int found = 0;
5232
5233 mutex_lock(&ls->ls_waiters_mutex);
5234 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
5235 if (lkb->lkb_flags & DLM_IFL_RESEND) {
5236 hold_lkb(lkb);
5237 found = 1;
5238 break;
5239 }
5240 }
5241 mutex_unlock(&ls->ls_waiters_mutex);
5242
5243 if (!found)
5244 lkb = NULL;
5245 return lkb;
5246}
5247
5248/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5249 master or dir-node for r. Processing the lkb may result in it being placed
5250 back on waiters. */
5251
5252/* We do this after normal locking has been enabled and any saved messages
5253 (in requestqueue) have been processed. We should be confident that at
5254 this point we won't get or process a reply to any of these waiting
5255 operations. But, new ops may be coming in on the rsbs/locks here from
5256 userspace or remotely. */
5257
5258/* there may have been an overlap unlock/cancel prior to recovery or after
5259 recovery. if before, the lkb may still have a pos wait_count; if after, the
5260 overlap flag would just have been set and nothing new sent. we can be
5261 confident here than any replies to either the initial op or overlap ops
5262 prior to recovery have been received. */
5263
5264int dlm_recover_waiters_post(struct dlm_ls *ls)
5265{
5266 struct dlm_lkb *lkb;
5267 struct dlm_rsb *r;
5268 int error = 0, mstype, err, oc, ou;
5269
5270 while (1) {
5271 if (dlm_locking_stopped(ls)) {
5272 log_debug(ls, "recover_waiters_post aborted");
5273 error = -EINTR;
5274 break;
5275 }
5276
5277 lkb = find_resend_waiter(ls);
5278 if (!lkb)
5279 break;
5280
5281 r = lkb->lkb_resource;
5282 hold_rsb(r);
5283 lock_rsb(r);
5284
5285 mstype = lkb->lkb_wait_type;
5286 oc = is_overlap_cancel(lkb);
5287 ou = is_overlap_unlock(lkb);
5288 err = 0;
5289
5290 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5291 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5292 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5293 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5294 dlm_dir_nodeid(r), oc, ou);
5295
5296 /* At this point we assume that we won't get a reply to any
5297 previous op or overlap op on this lock. First, do a big
5298 remove_from_waiters() for all previous ops. */
5299
5300 lkb->lkb_flags &= ~DLM_IFL_RESEND;
5301 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
5302 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
5303 lkb->lkb_wait_type = 0;
5304 lkb->lkb_wait_count = 0;
5305 mutex_lock(&ls->ls_waiters_mutex);
5306 list_del_init(&lkb->lkb_wait_reply);
5307 mutex_unlock(&ls->ls_waiters_mutex);
5308 unhold_lkb(lkb); /* for waiters list */
5309
5310 if (oc || ou) {
5311 /* do an unlock or cancel instead of resending */
5312 switch (mstype) {
5313 case DLM_MSG_LOOKUP:
5314 case DLM_MSG_REQUEST:
5315 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5316 -DLM_ECANCEL);
5317 unhold_lkb(lkb); /* undoes create_lkb() */
5318 break;
5319 case DLM_MSG_CONVERT:
5320 if (oc) {
5321 queue_cast(r, lkb, -DLM_ECANCEL);
5322 } else {
5323 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5324 _unlock_lock(r, lkb);
5325 }
5326 break;
5327 default:
5328 err = 1;
5329 }
5330 } else {
5331 switch (mstype) {
5332 case DLM_MSG_LOOKUP:
5333 case DLM_MSG_REQUEST:
5334 _request_lock(r, lkb);
5335 if (is_master(r))
5336 confirm_master(r, 0);
5337 break;
5338 case DLM_MSG_CONVERT:
5339 _convert_lock(r, lkb);
5340 break;
5341 default:
5342 err = 1;
5343 }
5344 }
5345
5346 if (err) {
5347 log_error(ls, "waiter %x msg %d r_nodeid %d "
5348 "dir_nodeid %d overlap %d %d",
5349 lkb->lkb_id, mstype, r->res_nodeid,
5350 dlm_dir_nodeid(r), oc, ou);
5351 }
5352 unlock_rsb(r);
5353 put_rsb(r);
5354 dlm_put_lkb(lkb);
5355 }
5356
5357 return error;
5358}
5359
5360static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5361 struct list_head *list)
5362{
5363 struct dlm_lkb *lkb, *safe;
5364
5365 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5366 if (!is_master_copy(lkb))
5367 continue;
5368
5369 /* don't purge lkbs we've added in recover_master_copy for
5370 the current recovery seq */
5371
5372 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5373 continue;
5374
5375 del_lkb(r, lkb);
5376
5377 /* this put should free the lkb */
5378 if (!dlm_put_lkb(lkb))
5379 log_error(ls, "purged mstcpy lkb not released");
5380 }
5381}
5382
5383void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
5384{
5385 struct dlm_ls *ls = r->res_ls;
5386
5387 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5388 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5389 purge_mstcpy_list(ls, r, &r->res_waitqueue);
5390}
5391
5392static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5393 struct list_head *list,
5394 int nodeid_gone, unsigned int *count)
5395{
5396 struct dlm_lkb *lkb, *safe;
5397
5398 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5399 if (!is_master_copy(lkb))
5400 continue;
5401
5402 if ((lkb->lkb_nodeid == nodeid_gone) ||
5403 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5404
5405 /* tell recover_lvb to invalidate the lvb
5406 because a node holding EX/PW failed */
5407 if ((lkb->lkb_exflags & DLM_LKF_VALBLK) &&
5408 (lkb->lkb_grmode >= DLM_LOCK_PW)) {
5409 rsb_set_flag(r, RSB_RECOVER_LVB_INVAL);
5410 }
5411
5412 del_lkb(r, lkb);
5413
5414 /* this put should free the lkb */
5415 if (!dlm_put_lkb(lkb))
5416 log_error(ls, "purged dead lkb not released");
5417
5418 rsb_set_flag(r, RSB_RECOVER_GRANT);
5419
5420 (*count)++;
5421 }
5422 }
5423}
5424
5425/* Get rid of locks held by nodes that are gone. */
5426
5427void dlm_recover_purge(struct dlm_ls *ls)
5428{
5429 struct dlm_rsb *r;
5430 struct dlm_member *memb;
5431 int nodes_count = 0;
5432 int nodeid_gone = 0;
5433 unsigned int lkb_count = 0;
5434
5435 /* cache one removed nodeid to optimize the common
5436 case of a single node removed */
5437
5438 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5439 nodes_count++;
5440 nodeid_gone = memb->nodeid;
5441 }
5442
5443 if (!nodes_count)
5444 return;
5445
5446 down_write(&ls->ls_root_sem);
5447 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5448 hold_rsb(r);
5449 lock_rsb(r);
5450 if (is_master(r)) {
5451 purge_dead_list(ls, r, &r->res_grantqueue,
5452 nodeid_gone, &lkb_count);
5453 purge_dead_list(ls, r, &r->res_convertqueue,
5454 nodeid_gone, &lkb_count);
5455 purge_dead_list(ls, r, &r->res_waitqueue,
5456 nodeid_gone, &lkb_count);
5457 }
5458 unlock_rsb(r);
5459 unhold_rsb(r);
5460 cond_resched();
5461 }
5462 up_write(&ls->ls_root_sem);
5463
5464 if (lkb_count)
5465 log_rinfo(ls, "dlm_recover_purge %u locks for %u nodes",
5466 lkb_count, nodes_count);
5467}
5468
5469static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
5470{
5471 struct rb_node *n;
5472 struct dlm_rsb *r;
5473
5474 spin_lock(&ls->ls_rsbtbl[bucket].lock);
5475 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5476 r = rb_entry(n, struct dlm_rsb, res_hashnode);
5477
5478 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5479 continue;
5480 if (!is_master(r)) {
5481 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5482 continue;
5483 }
5484 hold_rsb(r);
5485 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5486 return r;
5487 }
5488 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5489 return NULL;
5490}
5491
5492/*
5493 * Attempt to grant locks on resources that we are the master of.
5494 * Locks may have become grantable during recovery because locks
5495 * from departed nodes have been purged (or not rebuilt), allowing
5496 * previously blocked locks to now be granted. The subset of rsb's
5497 * we are interested in are those with lkb's on either the convert or
5498 * waiting queues.
5499 *
5500 * Simplest would be to go through each master rsb and check for non-empty
5501 * convert or waiting queues, and attempt to grant on those rsbs.
5502 * Checking the queues requires lock_rsb, though, for which we'd need
5503 * to release the rsbtbl lock. This would make iterating through all
5504 * rsb's very inefficient. So, we rely on earlier recovery routines
5505 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5506 * locks for.
5507 */
5508
5509void dlm_recover_grant(struct dlm_ls *ls)
5510{
5511 struct dlm_rsb *r;
5512 int bucket = 0;
5513 unsigned int count = 0;
5514 unsigned int rsb_count = 0;
5515 unsigned int lkb_count = 0;
5516
5517 while (1) {
5518 r = find_grant_rsb(ls, bucket);
5519 if (!r) {
5520 if (bucket == ls->ls_rsbtbl_size - 1)
5521 break;
5522 bucket++;
5523 continue;
5524 }
5525 rsb_count++;
5526 count = 0;
5527 lock_rsb(r);
5528 /* the RECOVER_GRANT flag is checked in the grant path */
5529 grant_pending_locks(r, &count);
5530 rsb_clear_flag(r, RSB_RECOVER_GRANT);
5531 lkb_count += count;
5532 confirm_master(r, 0);
5533 unlock_rsb(r);
5534 put_rsb(r);
5535 cond_resched();
5536 }
5537
5538 if (lkb_count)
5539 log_rinfo(ls, "dlm_recover_grant %u locks on %u resources",
5540 lkb_count, rsb_count);
5541}
5542
5543static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5544 uint32_t remid)
5545{
5546 struct dlm_lkb *lkb;
5547
5548 list_for_each_entry(lkb, head, lkb_statequeue) {
5549 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5550 return lkb;
5551 }
5552 return NULL;
5553}
5554
5555static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5556 uint32_t remid)
5557{
5558 struct dlm_lkb *lkb;
5559
5560 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5561 if (lkb)
5562 return lkb;
5563 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5564 if (lkb)
5565 return lkb;
5566 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5567 if (lkb)
5568 return lkb;
5569 return NULL;
5570}
5571
5572/* needs at least dlm_rcom + rcom_lock */
5573static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5574 struct dlm_rsb *r, struct dlm_rcom *rc)
5575{
5576 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5577
5578 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
5579 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5580 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5581 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5582 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
5583 lkb->lkb_flags |= DLM_IFL_MSTCPY;
5584 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
5585 lkb->lkb_rqmode = rl->rl_rqmode;
5586 lkb->lkb_grmode = rl->rl_grmode;
5587 /* don't set lkb_status because add_lkb wants to itself */
5588
5589 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5590 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
5591
5592 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
5593 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
5594 sizeof(struct rcom_lock);
5595 if (lvblen > ls->ls_lvblen)
5596 return -EINVAL;
5597 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
5598 if (!lkb->lkb_lvbptr)
5599 return -ENOMEM;
5600 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5601 }
5602
5603 /* Conversions between PR and CW (middle modes) need special handling.
5604 The real granted mode of these converting locks cannot be determined
5605 until all locks have been rebuilt on the rsb (recover_conversion) */
5606
5607 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5608 middle_conversion(lkb)) {
5609 rl->rl_status = DLM_LKSTS_CONVERT;
5610 lkb->lkb_grmode = DLM_LOCK_IV;
5611 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5612 }
5613
5614 return 0;
5615}
5616
5617/* This lkb may have been recovered in a previous aborted recovery so we need
5618 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5619 If so we just send back a standard reply. If not, we create a new lkb with
5620 the given values and send back our lkid. We send back our lkid by sending
5621 back the rcom_lock struct we got but with the remid field filled in. */
5622
5623/* needs at least dlm_rcom + rcom_lock */
5624int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5625{
5626 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5627 struct dlm_rsb *r;
5628 struct dlm_lkb *lkb;
5629 uint32_t remid = 0;
5630 int from_nodeid = rc->rc_header.h_nodeid;
5631 int error;
5632
5633 if (rl->rl_parent_lkid) {
5634 error = -EOPNOTSUPP;
5635 goto out;
5636 }
5637
5638 remid = le32_to_cpu(rl->rl_lkid);
5639
5640 /* In general we expect the rsb returned to be R_MASTER, but we don't
5641 have to require it. Recovery of masters on one node can overlap
5642 recovery of locks on another node, so one node can send us MSTCPY
5643 locks before we've made ourselves master of this rsb. We can still
5644 add new MSTCPY locks that we receive here without any harm; when
5645 we make ourselves master, dlm_recover_masters() won't touch the
5646 MSTCPY locks we've received early. */
5647
5648 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5649 from_nodeid, R_RECEIVE_RECOVER, &r);
5650 if (error)
5651 goto out;
5652
5653 lock_rsb(r);
5654
5655 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5656 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
5657 from_nodeid, remid);
5658 error = -EBADR;
5659 goto out_unlock;
5660 }
5661
5662 lkb = search_remid(r, from_nodeid, remid);
5663 if (lkb) {
5664 error = -EEXIST;
5665 goto out_remid;
5666 }
5667
5668 error = create_lkb(ls, &lkb);
5669 if (error)
5670 goto out_unlock;
5671
5672 error = receive_rcom_lock_args(ls, lkb, r, rc);
5673 if (error) {
5674 __put_lkb(ls, lkb);
5675 goto out_unlock;
5676 }
5677
5678 attach_lkb(r, lkb);
5679 add_lkb(r, lkb, rl->rl_status);
5680 error = 0;
5681 ls->ls_recover_locks_in++;
5682
5683 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5684 rsb_set_flag(r, RSB_RECOVER_GRANT);
5685
5686 out_remid:
5687 /* this is the new value returned to the lock holder for
5688 saving in its process-copy lkb */
5689 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
5690
5691 lkb->lkb_recover_seq = ls->ls_recover_seq;
5692
5693 out_unlock:
5694 unlock_rsb(r);
5695 put_rsb(r);
5696 out:
5697 if (error && error != -EEXIST)
5698 log_rinfo(ls, "dlm_recover_master_copy remote %d %x error %d",
5699 from_nodeid, remid, error);
5700 rl->rl_result = cpu_to_le32(error);
5701 return error;
5702}
5703
5704/* needs at least dlm_rcom + rcom_lock */
5705int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5706{
5707 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5708 struct dlm_rsb *r;
5709 struct dlm_lkb *lkb;
5710 uint32_t lkid, remid;
5711 int error, result;
5712
5713 lkid = le32_to_cpu(rl->rl_lkid);
5714 remid = le32_to_cpu(rl->rl_remid);
5715 result = le32_to_cpu(rl->rl_result);
5716
5717 error = find_lkb(ls, lkid, &lkb);
5718 if (error) {
5719 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5720 lkid, rc->rc_header.h_nodeid, remid, result);
5721 return error;
5722 }
5723
5724 r = lkb->lkb_resource;
5725 hold_rsb(r);
5726 lock_rsb(r);
5727
5728 if (!is_process_copy(lkb)) {
5729 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5730 lkid, rc->rc_header.h_nodeid, remid, result);
5731 dlm_dump_rsb(r);
5732 unlock_rsb(r);
5733 put_rsb(r);
5734 dlm_put_lkb(lkb);
5735 return -EINVAL;
5736 }
5737
5738 switch (result) {
5739 case -EBADR:
5740 /* There's a chance the new master received our lock before
5741 dlm_recover_master_reply(), this wouldn't happen if we did
5742 a barrier between recover_masters and recover_locks. */
5743
5744 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5745 lkid, rc->rc_header.h_nodeid, remid, result);
5746
5747 dlm_send_rcom_lock(r, lkb);
5748 goto out;
5749 case -EEXIST:
5750 case 0:
5751 lkb->lkb_remid = remid;
5752 break;
5753 default:
5754 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5755 lkid, rc->rc_header.h_nodeid, remid, result);
5756 }
5757
5758 /* an ack for dlm_recover_locks() which waits for replies from
5759 all the locks it sends to new masters */
5760 dlm_recovered_lock(r);
5761 out:
5762 unlock_rsb(r);
5763 put_rsb(r);
5764 dlm_put_lkb(lkb);
5765
5766 return 0;
5767}
5768
5769int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5770 int mode, uint32_t flags, void *name, unsigned int namelen,
5771 unsigned long timeout_cs)
5772{
5773 struct dlm_lkb *lkb;
5774 struct dlm_args args;
5775 int error;
5776
5777 dlm_lock_recovery(ls);
5778
5779 error = create_lkb(ls, &lkb);
5780 if (error) {
5781 kfree(ua);
5782 goto out;
5783 }
5784
5785 if (flags & DLM_LKF_VALBLK) {
5786 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5787 if (!ua->lksb.sb_lvbptr) {
5788 kfree(ua);
5789 __put_lkb(ls, lkb);
5790 error = -ENOMEM;
5791 goto out;
5792 }
5793 }
5794 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
5795 fake_astfn, ua, fake_bastfn, &args);
5796 if (error) {
5797 kfree(ua->lksb.sb_lvbptr);
5798 ua->lksb.sb_lvbptr = NULL;
5799 kfree(ua);
5800 __put_lkb(ls, lkb);
5801 goto out;
5802 }
5803
5804 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
5805 When DLM_IFL_USER is set, the dlm knows that this is a userspace
5806 lock and that lkb_astparam is the dlm_user_args structure. */
5807 lkb->lkb_flags |= DLM_IFL_USER;
5808 error = request_lock(ls, lkb, name, namelen, &args);
5809
5810 switch (error) {
5811 case 0:
5812 break;
5813 case -EINPROGRESS:
5814 error = 0;
5815 break;
5816 case -EAGAIN:
5817 error = 0;
5818 fallthrough;
5819 default:
5820 __put_lkb(ls, lkb);
5821 goto out;
5822 }
5823
5824 /* add this new lkb to the per-process list of locks */
5825 spin_lock(&ua->proc->locks_spin);
5826 hold_lkb(lkb);
5827 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5828 spin_unlock(&ua->proc->locks_spin);
5829 out:
5830 dlm_unlock_recovery(ls);
5831 return error;
5832}
5833
5834int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5835 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
5836 unsigned long timeout_cs)
5837{
5838 struct dlm_lkb *lkb;
5839 struct dlm_args args;
5840 struct dlm_user_args *ua;
5841 int error;
5842
5843 dlm_lock_recovery(ls);
5844
5845 error = find_lkb(ls, lkid, &lkb);
5846 if (error)
5847 goto out;
5848
5849 /* user can change the params on its lock when it converts it, or
5850 add an lvb that didn't exist before */
5851
5852 ua = lkb->lkb_ua;
5853
5854 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
5855 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
5856 if (!ua->lksb.sb_lvbptr) {
5857 error = -ENOMEM;
5858 goto out_put;
5859 }
5860 }
5861 if (lvb_in && ua->lksb.sb_lvbptr)
5862 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5863
5864 ua->xid = ua_tmp->xid;
5865 ua->castparam = ua_tmp->castparam;
5866 ua->castaddr = ua_tmp->castaddr;
5867 ua->bastparam = ua_tmp->bastparam;
5868 ua->bastaddr = ua_tmp->bastaddr;
5869 ua->user_lksb = ua_tmp->user_lksb;
5870
5871 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
5872 fake_astfn, ua, fake_bastfn, &args);
5873 if (error)
5874 goto out_put;
5875
5876 error = convert_lock(ls, lkb, &args);
5877
5878 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
5879 error = 0;
5880 out_put:
5881 dlm_put_lkb(lkb);
5882 out:
5883 dlm_unlock_recovery(ls);
5884 kfree(ua_tmp);
5885 return error;
5886}
5887
5888/*
5889 * The caller asks for an orphan lock on a given resource with a given mode.
5890 * If a matching lock exists, it's moved to the owner's list of locks and
5891 * the lkid is returned.
5892 */
5893
5894int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5895 int mode, uint32_t flags, void *name, unsigned int namelen,
5896 unsigned long timeout_cs, uint32_t *lkid)
5897{
5898 struct dlm_lkb *lkb;
5899 struct dlm_user_args *ua;
5900 int found_other_mode = 0;
5901 int found = 0;
5902 int rv = 0;
5903
5904 mutex_lock(&ls->ls_orphans_mutex);
5905 list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) {
5906 if (lkb->lkb_resource->res_length != namelen)
5907 continue;
5908 if (memcmp(lkb->lkb_resource->res_name, name, namelen))
5909 continue;
5910 if (lkb->lkb_grmode != mode) {
5911 found_other_mode = 1;
5912 continue;
5913 }
5914
5915 found = 1;
5916 list_del_init(&lkb->lkb_ownqueue);
5917 lkb->lkb_flags &= ~DLM_IFL_ORPHAN;
5918 *lkid = lkb->lkb_id;
5919 break;
5920 }
5921 mutex_unlock(&ls->ls_orphans_mutex);
5922
5923 if (!found && found_other_mode) {
5924 rv = -EAGAIN;
5925 goto out;
5926 }
5927
5928 if (!found) {
5929 rv = -ENOENT;
5930 goto out;
5931 }
5932
5933 lkb->lkb_exflags = flags;
5934 lkb->lkb_ownpid = (int) current->pid;
5935
5936 ua = lkb->lkb_ua;
5937
5938 ua->proc = ua_tmp->proc;
5939 ua->xid = ua_tmp->xid;
5940 ua->castparam = ua_tmp->castparam;
5941 ua->castaddr = ua_tmp->castaddr;
5942 ua->bastparam = ua_tmp->bastparam;
5943 ua->bastaddr = ua_tmp->bastaddr;
5944 ua->user_lksb = ua_tmp->user_lksb;
5945
5946 /*
5947 * The lkb reference from the ls_orphans list was not
5948 * removed above, and is now considered the reference
5949 * for the proc locks list.
5950 */
5951
5952 spin_lock(&ua->proc->locks_spin);
5953 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5954 spin_unlock(&ua->proc->locks_spin);
5955 out:
5956 kfree(ua_tmp);
5957 return rv;
5958}
5959
5960int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5961 uint32_t flags, uint32_t lkid, char *lvb_in)
5962{
5963 struct dlm_lkb *lkb;
5964 struct dlm_args args;
5965 struct dlm_user_args *ua;
5966 int error;
5967
5968 dlm_lock_recovery(ls);
5969
5970 error = find_lkb(ls, lkid, &lkb);
5971 if (error)
5972 goto out;
5973
5974 ua = lkb->lkb_ua;
5975
5976 if (lvb_in && ua->lksb.sb_lvbptr)
5977 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5978 if (ua_tmp->castparam)
5979 ua->castparam = ua_tmp->castparam;
5980 ua->user_lksb = ua_tmp->user_lksb;
5981
5982 error = set_unlock_args(flags, ua, &args);
5983 if (error)
5984 goto out_put;
5985
5986 error = unlock_lock(ls, lkb, &args);
5987
5988 if (error == -DLM_EUNLOCK)
5989 error = 0;
5990 /* from validate_unlock_args() */
5991 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5992 error = 0;
5993 if (error)
5994 goto out_put;
5995
5996 spin_lock(&ua->proc->locks_spin);
5997 /* dlm_user_add_cb() may have already taken lkb off the proc list */
5998 if (!list_empty(&lkb->lkb_ownqueue))
5999 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
6000 spin_unlock(&ua->proc->locks_spin);
6001 out_put:
6002 dlm_put_lkb(lkb);
6003 out:
6004 dlm_unlock_recovery(ls);
6005 kfree(ua_tmp);
6006 return error;
6007}
6008
6009int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
6010 uint32_t flags, uint32_t lkid)
6011{
6012 struct dlm_lkb *lkb;
6013 struct dlm_args args;
6014 struct dlm_user_args *ua;
6015 int error;
6016
6017 dlm_lock_recovery(ls);
6018
6019 error = find_lkb(ls, lkid, &lkb);
6020 if (error)
6021 goto out;
6022
6023 ua = lkb->lkb_ua;
6024 if (ua_tmp->castparam)
6025 ua->castparam = ua_tmp->castparam;
6026 ua->user_lksb = ua_tmp->user_lksb;
6027
6028 error = set_unlock_args(flags, ua, &args);
6029 if (error)
6030 goto out_put;
6031
6032 error = cancel_lock(ls, lkb, &args);
6033
6034 if (error == -DLM_ECANCEL)
6035 error = 0;
6036 /* from validate_unlock_args() */
6037 if (error == -EBUSY)
6038 error = 0;
6039 out_put:
6040 dlm_put_lkb(lkb);
6041 out:
6042 dlm_unlock_recovery(ls);
6043 kfree(ua_tmp);
6044 return error;
6045}
6046
6047int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
6048{
6049 struct dlm_lkb *lkb;
6050 struct dlm_args args;
6051 struct dlm_user_args *ua;
6052 struct dlm_rsb *r;
6053 int error;
6054
6055 dlm_lock_recovery(ls);
6056
6057 error = find_lkb(ls, lkid, &lkb);
6058 if (error)
6059 goto out;
6060
6061 ua = lkb->lkb_ua;
6062
6063 error = set_unlock_args(flags, ua, &args);
6064 if (error)
6065 goto out_put;
6066
6067 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
6068
6069 r = lkb->lkb_resource;
6070 hold_rsb(r);
6071 lock_rsb(r);
6072
6073 error = validate_unlock_args(lkb, &args);
6074 if (error)
6075 goto out_r;
6076 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
6077
6078 error = _cancel_lock(r, lkb);
6079 out_r:
6080 unlock_rsb(r);
6081 put_rsb(r);
6082
6083 if (error == -DLM_ECANCEL)
6084 error = 0;
6085 /* from validate_unlock_args() */
6086 if (error == -EBUSY)
6087 error = 0;
6088 out_put:
6089 dlm_put_lkb(lkb);
6090 out:
6091 dlm_unlock_recovery(ls);
6092 return error;
6093}
6094
6095/* lkb's that are removed from the waiters list by revert are just left on the
6096 orphans list with the granted orphan locks, to be freed by purge */
6097
6098static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6099{
6100 struct dlm_args args;
6101 int error;
6102
6103 hold_lkb(lkb); /* reference for the ls_orphans list */
6104 mutex_lock(&ls->ls_orphans_mutex);
6105 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
6106 mutex_unlock(&ls->ls_orphans_mutex);
6107
6108 set_unlock_args(0, lkb->lkb_ua, &args);
6109
6110 error = cancel_lock(ls, lkb, &args);
6111 if (error == -DLM_ECANCEL)
6112 error = 0;
6113 return error;
6114}
6115
6116/* The FORCEUNLOCK flag allows the unlock to go ahead even if the lkb isn't
6117 granted. Regardless of what rsb queue the lock is on, it's removed and
6118 freed. The IVVALBLK flag causes the lvb on the resource to be invalidated
6119 if our lock is PW/EX (it's ignored if our granted mode is smaller.) */
6120
6121static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6122{
6123 struct dlm_args args;
6124 int error;
6125
6126 set_unlock_args(DLM_LKF_FORCEUNLOCK | DLM_LKF_IVVALBLK,
6127 lkb->lkb_ua, &args);
6128
6129 error = unlock_lock(ls, lkb, &args);
6130 if (error == -DLM_EUNLOCK)
6131 error = 0;
6132 return error;
6133}
6134
6135/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
6136 (which does lock_rsb) due to deadlock with receiving a message that does
6137 lock_rsb followed by dlm_user_add_cb() */
6138
6139static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
6140 struct dlm_user_proc *proc)
6141{
6142 struct dlm_lkb *lkb = NULL;
6143
6144 mutex_lock(&ls->ls_clear_proc_locks);
6145 if (list_empty(&proc->locks))
6146 goto out;
6147
6148 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
6149 list_del_init(&lkb->lkb_ownqueue);
6150
6151 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6152 lkb->lkb_flags |= DLM_IFL_ORPHAN;
6153 else
6154 lkb->lkb_flags |= DLM_IFL_DEAD;
6155 out:
6156 mutex_unlock(&ls->ls_clear_proc_locks);
6157 return lkb;
6158}
6159
6160/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
6161 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
6162 which we clear here. */
6163
6164/* proc CLOSING flag is set so no more device_reads should look at proc->asts
6165 list, and no more device_writes should add lkb's to proc->locks list; so we
6166 shouldn't need to take asts_spin or locks_spin here. this assumes that
6167 device reads/writes/closes are serialized -- FIXME: we may need to serialize
6168 them ourself. */
6169
6170void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6171{
6172 struct dlm_lkb *lkb, *safe;
6173
6174 dlm_lock_recovery(ls);
6175
6176 while (1) {
6177 lkb = del_proc_lock(ls, proc);
6178 if (!lkb)
6179 break;
6180 del_timeout(lkb);
6181 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6182 orphan_proc_lock(ls, lkb);
6183 else
6184 unlock_proc_lock(ls, lkb);
6185
6186 /* this removes the reference for the proc->locks list
6187 added by dlm_user_request, it may result in the lkb
6188 being freed */
6189
6190 dlm_put_lkb(lkb);
6191 }
6192
6193 mutex_lock(&ls->ls_clear_proc_locks);
6194
6195 /* in-progress unlocks */
6196 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6197 list_del_init(&lkb->lkb_ownqueue);
6198 lkb->lkb_flags |= DLM_IFL_DEAD;
6199 dlm_put_lkb(lkb);
6200 }
6201
6202 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
6203 memset(&lkb->lkb_callbacks, 0,
6204 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
6205 list_del_init(&lkb->lkb_cb_list);
6206 dlm_put_lkb(lkb);
6207 }
6208
6209 mutex_unlock(&ls->ls_clear_proc_locks);
6210 dlm_unlock_recovery(ls);
6211}
6212
6213static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6214{
6215 struct dlm_lkb *lkb, *safe;
6216
6217 while (1) {
6218 lkb = NULL;
6219 spin_lock(&proc->locks_spin);
6220 if (!list_empty(&proc->locks)) {
6221 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6222 lkb_ownqueue);
6223 list_del_init(&lkb->lkb_ownqueue);
6224 }
6225 spin_unlock(&proc->locks_spin);
6226
6227 if (!lkb)
6228 break;
6229
6230 lkb->lkb_flags |= DLM_IFL_DEAD;
6231 unlock_proc_lock(ls, lkb);
6232 dlm_put_lkb(lkb); /* ref from proc->locks list */
6233 }
6234
6235 spin_lock(&proc->locks_spin);
6236 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6237 list_del_init(&lkb->lkb_ownqueue);
6238 lkb->lkb_flags |= DLM_IFL_DEAD;
6239 dlm_put_lkb(lkb);
6240 }
6241 spin_unlock(&proc->locks_spin);
6242
6243 spin_lock(&proc->asts_spin);
6244 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
6245 memset(&lkb->lkb_callbacks, 0,
6246 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
6247 list_del_init(&lkb->lkb_cb_list);
6248 dlm_put_lkb(lkb);
6249 }
6250 spin_unlock(&proc->asts_spin);
6251}
6252
6253/* pid of 0 means purge all orphans */
6254
6255static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6256{
6257 struct dlm_lkb *lkb, *safe;
6258
6259 mutex_lock(&ls->ls_orphans_mutex);
6260 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6261 if (pid && lkb->lkb_ownpid != pid)
6262 continue;
6263 unlock_proc_lock(ls, lkb);
6264 list_del_init(&lkb->lkb_ownqueue);
6265 dlm_put_lkb(lkb);
6266 }
6267 mutex_unlock(&ls->ls_orphans_mutex);
6268}
6269
6270static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6271{
6272 struct dlm_message *ms;
6273 struct dlm_mhandle *mh;
6274 int error;
6275
6276 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6277 DLM_MSG_PURGE, &ms, &mh);
6278 if (error)
6279 return error;
6280 ms->m_nodeid = nodeid;
6281 ms->m_pid = pid;
6282
6283 return send_message(mh, ms);
6284}
6285
6286int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6287 int nodeid, int pid)
6288{
6289 int error = 0;
6290
6291 if (nodeid && (nodeid != dlm_our_nodeid())) {
6292 error = send_purge(ls, nodeid, pid);
6293 } else {
6294 dlm_lock_recovery(ls);
6295 if (pid == current->pid)
6296 purge_proc_locks(ls, proc);
6297 else
6298 do_purge(ls, nodeid, pid);
6299 dlm_unlock_recovery(ls);
6300 }
6301 return error;
6302}
6303