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fs/dlm: remove CONFIG_EXPERIMENTAL
[deliverable/linux.git] / fs / dlm / lock.c
CommitLineData
e7fd4179
DT		 1/******************************************************************************
2*******************************************************************************
3**
7fe2b319 4** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
e7fd4179
DT		 5**
6** This copyrighted material is made available to anyone wishing to use,
7** modify, copy, or redistribute it subject to the terms and conditions
8** of the GNU General Public License v.2.
9**
10*******************************************************************************
11******************************************************************************/
12
13/* Central locking logic has four stages:
14
15 dlm_lock()
16 dlm_unlock()
17
18 request_lock(ls, lkb)
19 convert_lock(ls, lkb)
20 unlock_lock(ls, lkb)
21 cancel_lock(ls, lkb)
22
23 _request_lock(r, lkb)
24 _convert_lock(r, lkb)
25 _unlock_lock(r, lkb)
26 _cancel_lock(r, lkb)
27
28 do_request(r, lkb)
29 do_convert(r, lkb)
30 do_unlock(r, lkb)
31 do_cancel(r, lkb)
32
33 Stage 1 (lock, unlock) is mainly about checking input args and
34 splitting into one of the four main operations:
35
36 dlm_lock = request_lock
37 dlm_lock+CONVERT = convert_lock
38 dlm_unlock = unlock_lock
39 dlm_unlock+CANCEL = cancel_lock
40
41 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
42 provided to the next stage.
43
44 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
45 When remote, it calls send_xxxx(), when local it calls do_xxxx().
46
47 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
48 given rsb and lkb and queues callbacks.
49
50 For remote operations, send_xxxx() results in the corresponding do_xxxx()
51 function being executed on the remote node. The connecting send/receive
52 calls on local (L) and remote (R) nodes:
53
54 L: send_xxxx() -> R: receive_xxxx()
55 R: do_xxxx()
56 L: receive_xxxx_reply() <- R: send_xxxx_reply()
57*/
597d0cae 58#include <linux/types.h>
9beb3bf5 59#include <linux/rbtree.h>
5a0e3ad6 60#include <linux/slab.h>
e7fd4179 61#include "dlm_internal.h"
597d0cae 62#include <linux/dlm_device.h>
e7fd4179
DT		 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"
597d0cae 75#include "user.h"
e7fd4179
DT		 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);
3ae1acf9 87static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
e7fd4179
DT		 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);
8499137d 91static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
3ae1acf9 92static void del_timeout(struct dlm_lkb *lkb);
c04fecb4 93static void toss_rsb(struct kref *kref);
e7fd4179
DT		 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};
e7fd4179
DT		 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
597d0cae 162void dlm_print_lkb(struct dlm_lkb *lkb)
e7fd4179 163{
6d40c4a7 164 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
4875647a 165 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
e7fd4179
DT		 166 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
167 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
4875647a
DT		 168 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
169 (unsigned long long)lkb->lkb_recover_seq);
e7fd4179
DT		 170}
171
170e19ab 172static void dlm_print_rsb(struct dlm_rsb *r)
e7fd4179 173{
c04fecb4
DT		 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);
e7fd4179
DT		 179}
180
a345da3e
DT		 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
e7fd4179
DT		 203/* Threads cannot use the lockspace while it's being recovered */
204
85e86edf 205static inline void dlm_lock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 206{
207 down_read(&ls->ls_in_recovery);
208}
209
85e86edf 210void dlm_unlock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 211{
212 up_read(&ls->ls_in_recovery);
213}
214
85e86edf 215int dlm_lock_recovery_try(struct dlm_ls *ls)
e7fd4179
DT		 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
7d3c1feb
DT		 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
e7fd4179
DT		 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{
90135925 258 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
e7fd4179
DT		 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))
90135925
DT		 265 return 1;
266 return 0;
e7fd4179
DT		 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
ef0c2bb0
DT		 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
e7fd4179
DT		 290static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
291{
292 if (is_master_copy(lkb))
293 return;
294
3ae1acf9
DT		 295 del_timeout(lkb);
296
e7fd4179
DT		 297 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
298
3ae1acf9
DT		 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
8b4021fa
DT		 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
23e8e1aa 311 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
e7fd4179
DT		 312}
313
ef0c2bb0
DT		 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
e7fd4179
DT		 320static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
321{
b6fa8796 322 if (is_master_copy(lkb)) {
e7fd4179 323 send_bast(r, lkb, rqmode);
b6fa8796 324 } else {
23e8e1aa 325 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
b6fa8796 326 }
e7fd4179
DT		 327}
328
329/*
330 * Basic operations on rsb's and lkb's
331 */
332
c04fecb4
DT		 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
3881ac04
DT		 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)
e7fd4179
DT		 402{
403 struct dlm_rsb *r;
3881ac04
DT		 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 }
e7fd4179 414
3881ac04
DT		 415 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
416 list_del(&r->res_hashchain);
9beb3bf5
BP		 417 /* Convert the empty list_head to a NULL rb_node for tree usage: */
418 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
3881ac04
DT		 419 ls->ls_new_rsb_count--;
420 spin_unlock(&ls->ls_new_rsb_spin);
e7fd4179
DT		 421
422 r->res_ls = ls;
423 r->res_length = len;
424 memcpy(r->res_name, name, len);
90135925 425 mutex_init(&r->res_mutex);
e7fd4179
DT		 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
3881ac04
DT		 434 *r_ret = r;
435 return 0;
e7fd4179
DT		 436}
437
9beb3bf5
BP		 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
7210cb7a 447int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
c04fecb4 448 struct dlm_rsb **r_ret)
e7fd4179 449{
9beb3bf5 450 struct rb_node *node = tree->rb_node;
e7fd4179 451 struct dlm_rsb *r;
9beb3bf5
BP		 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
e7fd4179
DT		 462 goto found;
463 }
18c60c0a 464 *r_ret = NULL;
597d0cae 465 return -EBADR;
e7fd4179
DT		 466
467 found:
e7fd4179 468 *r_ret = r;
c04fecb4 469 return 0;
e7fd4179
DT		 470}
471
9beb3bf5
BP		 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
c04fecb4
DT		 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)
e7fd4179 549{
c04fecb4
DT		 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;
e7fd4179
DT		 556 int error;
557
c04fecb4
DT		 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;
e7fd4179 585 }
57638bf3 586
c04fecb4
DT		 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);
e7fd4179 597 if (error)
c04fecb4
DT		 598 goto do_toss;
599
600 /*
601 * rsb is active, so we can't check master_nodeid without lock_rsb.
602 */
e7fd4179 603
c04fecb4
DT		 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);
9beb3bf5 611 if (error)
c04fecb4 612 goto do_new;
e7fd4179 613
c04fecb4
DT		 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 */
e7fd4179 620
c04fecb4
DT		 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;
e7fd4179
DT		 639 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
640 r->res_first_lkid = 0;
c04fecb4
DT		 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. */
e7fd4179
DT		 646 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
647 r->res_first_lkid = 0;
c04fecb4
DT		 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 error = -ENOTBLK;
691 goto out_unlock;
692 }
693
694 if (from_other) {
695 log_debug(ls, "find_rsb new from_other %d dir %d %s",
696 from_nodeid, dir_nodeid, r->res_name);
697 }
698
699 if (dir_nodeid == our_nodeid) {
700 /* When we are the dir nodeid, we can set the master
701 node immediately */
702 r->res_master_nodeid = our_nodeid;
703 r->res_nodeid = 0;
e7fd4179 704 } else {
c04fecb4
DT		 705 /* set_master will send_lookup to dir_nodeid */
706 r->res_master_nodeid = 0;
707 r->res_nodeid = -1;
708 }
709
710 out_add:
711 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
712 out_unlock:
713 spin_unlock(&ls->ls_rsbtbl[b].lock);
714 out:
715 *r_ret = r;
716 return error;
717}
718
719/* During recovery, other nodes can send us new MSTCPY locks (from
720 dlm_recover_locks) before we've made ourself master (in
721 dlm_recover_masters). */
722
723static int find_rsb_nodir(struct dlm_ls *ls, char *name, int len,
724 uint32_t hash, uint32_t b,
725 int dir_nodeid, int from_nodeid,
726 unsigned int flags, struct dlm_rsb **r_ret)
727{
728 struct dlm_rsb *r = NULL;
729 int our_nodeid = dlm_our_nodeid();
730 int recover = (flags & R_RECEIVE_RECOVER);
731 int error;
732
733 retry:
734 error = pre_rsb_struct(ls);
735 if (error < 0)
736 goto out;
737
738 spin_lock(&ls->ls_rsbtbl[b].lock);
739
740 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
741 if (error)
742 goto do_toss;
743
744 /*
745 * rsb is active, so we can't check master_nodeid without lock_rsb.
746 */
747
748 kref_get(&r->res_ref);
749 goto out_unlock;
750
751
752 do_toss:
753 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
754 if (error)
755 goto do_new;
756
757 /*
758 * rsb found inactive. No other thread is using this rsb because
759 * it's on the toss list, so we can look at or update
760 * res_master_nodeid without lock_rsb.
761 */
762
763 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
764 /* our rsb is not master, and another node has sent us a
765 request; this should never happen */
766 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
767 from_nodeid, r->res_master_nodeid, dir_nodeid);
768 dlm_print_rsb(r);
769 error = -ENOTBLK;
770 goto out_unlock;
e7fd4179 771 }
c04fecb4
DT		 772
773 if (!recover && (r->res_master_nodeid != our_nodeid) &&
774 (dir_nodeid == our_nodeid)) {
775 /* our rsb is not master, and we are dir; may as well fix it;
776 this should never happen */
777 log_error(ls, "find_rsb toss our %d master %d dir %d",
778 our_nodeid, r->res_master_nodeid, dir_nodeid);
779 dlm_print_rsb(r);
780 r->res_master_nodeid = our_nodeid;
781 r->res_nodeid = 0;
782 }
783
784 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
785 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
786 goto out_unlock;
787
788
789 do_new:
790 /*
791 * rsb not found
792 */
793
794 error = get_rsb_struct(ls, name, len, &r);
795 if (error == -EAGAIN) {
796 spin_unlock(&ls->ls_rsbtbl[b].lock);
797 goto retry;
798 }
799 if (error)
800 goto out_unlock;
801
802 r->res_hash = hash;
803 r->res_bucket = b;
804 r->res_dir_nodeid = dir_nodeid;
805 r->res_master_nodeid = dir_nodeid;
806 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
807 kref_init(&r->res_ref);
808
809 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
810 out_unlock:
811 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 812 out:
813 *r_ret = r;
814 return error;
815}
816
c04fecb4
DT		 817static int find_rsb(struct dlm_ls *ls, char *name, int len, int from_nodeid,
818 unsigned int flags, struct dlm_rsb **r_ret)
819{
820 uint32_t hash, b;
821 int dir_nodeid;
822
823 if (len > DLM_RESNAME_MAXLEN)
824 return -EINVAL;
825
826 hash = jhash(name, len, 0);
827 b = hash & (ls->ls_rsbtbl_size - 1);
828
829 dir_nodeid = dlm_hash2nodeid(ls, hash);
830
831 if (dlm_no_directory(ls))
832 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
833 from_nodeid, flags, r_ret);
834 else
835 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
836 from_nodeid, flags, r_ret);
837}
838
839/* we have received a request and found that res_master_nodeid != our_nodeid,
840 so we need to return an error or make ourself the master */
841
842static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
843 int from_nodeid)
844{
845 if (dlm_no_directory(ls)) {
846 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
847 from_nodeid, r->res_master_nodeid,
848 r->res_dir_nodeid);
849 dlm_print_rsb(r);
850 return -ENOTBLK;
851 }
852
853 if (from_nodeid != r->res_dir_nodeid) {
854 /* our rsb is not master, and another node (not the dir node)
855 has sent us a request. this is much more common when our
856 master_nodeid is zero, so limit debug to non-zero. */
857
858 if (r->res_master_nodeid) {
859 log_debug(ls, "validate master from_other %d master %d "
860 "dir %d first %x %s", from_nodeid,
861 r->res_master_nodeid, r->res_dir_nodeid,
862 r->res_first_lkid, r->res_name);
863 }
864 return -ENOTBLK;
865 } else {
866 /* our rsb is not master, but the dir nodeid has sent us a
867 request; this could happen with master 0 / res_nodeid -1 */
868
869 if (r->res_master_nodeid) {
870 log_error(ls, "validate master from_dir %d master %d "
871 "first %x %s",
872 from_nodeid, r->res_master_nodeid,
873 r->res_first_lkid, r->res_name);
874 }
875
876 r->res_master_nodeid = dlm_our_nodeid();
877 r->res_nodeid = 0;
878 return 0;
879 }
880}
881
e7fd4179 882/*
c04fecb4
DT		 883 * We're the dir node for this res and another node wants to know the
884 * master nodeid. During normal operation (non recovery) this is only
885 * called from receive_lookup(); master lookups when the local node is
886 * the dir node are done by find_rsb().
e7fd4179 887 *
c04fecb4
DT		 888 * normal operation, we are the dir node for a resource
889 * . _request_lock
890 * . set_master
891 * . send_lookup
892 * . receive_lookup
893 * . dlm_master_lookup flags 0
e7fd4179 894 *
c04fecb4
DT		 895 * recover directory, we are rebuilding dir for all resources
896 * . dlm_recover_directory
897 * . dlm_rcom_names
898 * remote node sends back the rsb names it is master of and we are dir of
899 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
900 * we either create new rsb setting remote node as master, or find existing
901 * rsb and set master to be the remote node.
902 *
903 * recover masters, we are finding the new master for resources
904 * . dlm_recover_masters
905 * . recover_master
906 * . dlm_send_rcom_lookup
907 * . receive_rcom_lookup
908 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
e7fd4179
DT		 909 */
910
c04fecb4
DT		 911int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, char *name, int len,
912 unsigned int flags, int *r_nodeid, int *result)
e7fd4179 913{
3881ac04 914 struct dlm_rsb *r = NULL;
c04fecb4
DT		 915 uint32_t hash, b;
916 int from_master = (flags & DLM_LU_RECOVER_DIR);
917 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
918 int our_nodeid = dlm_our_nodeid();
919 int dir_nodeid, error, toss_list = 0;
ef58bcca 920
c04fecb4
DT		 921 if (len > DLM_RESNAME_MAXLEN)
922 return -EINVAL;
923
924 if (from_nodeid == our_nodeid) {
925 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
926 our_nodeid, flags);
927 return -EINVAL;
3881ac04 928 }
e7fd4179 929
c04fecb4
DT		 930 hash = jhash(name, len, 0);
931 b = hash & (ls->ls_rsbtbl_size - 1);
e7fd4179 932
c04fecb4
DT		 933 dir_nodeid = dlm_hash2nodeid(ls, hash);
934 if (dir_nodeid != our_nodeid) {
935 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
936 from_nodeid, dir_nodeid, our_nodeid, hash,
937 ls->ls_num_nodes);
938 *r_nodeid = -1;
939 return -EINVAL;
940 }
e7fd4179 941
3881ac04 942 retry:
c04fecb4
DT		 943 error = pre_rsb_struct(ls);
944 if (error < 0)
945 return error;
946
947 spin_lock(&ls->ls_rsbtbl[b].lock);
948 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
949 if (!error) {
950 /* because the rsb is active, we need to lock_rsb before
951 checking/changing re_master_nodeid */
952
953 hold_rsb(r);
954 spin_unlock(&ls->ls_rsbtbl[b].lock);
955 lock_rsb(r);
956 goto found;
3881ac04
DT		 957 }
958
c04fecb4
DT		 959 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
960 if (error)
961 goto not_found;
3881ac04 962
c04fecb4
DT		 963 /* because the rsb is inactive (on toss list), it's not refcounted
964 and lock_rsb is not used, but is protected by the rsbtbl lock */
e7fd4179 965
c04fecb4
DT		 966 toss_list = 1;
967 found:
968 if (r->res_dir_nodeid != our_nodeid) {
969 /* should not happen, but may as well fix it and carry on */
970 log_error(ls, "dlm_master_lookup res_dir %d our %d %s",
971 r->res_dir_nodeid, our_nodeid, r->res_name);
972 r->res_dir_nodeid = our_nodeid;
973 }
974
975 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
976 /* Recovery uses this function to set a new master when
977 the previous master failed. Setting NEW_MASTER will
978 force dlm_recover_masters to call recover_master on this
979 rsb even though the res_nodeid is no longer removed. */
980
981 r->res_master_nodeid = from_nodeid;
982 r->res_nodeid = from_nodeid;
983 rsb_set_flag(r, RSB_NEW_MASTER);
984
985 if (toss_list) {
986 /* I don't think we should ever find it on toss list. */
987 log_error(ls, "dlm_master_lookup fix_master on toss");
988 dlm_dump_rsb(r);
989 }
990 }
e7fd4179 991
c04fecb4
DT		 992 if (from_master && (r->res_master_nodeid != from_nodeid)) {
993 /* this will happen if from_nodeid became master during
994 a previous recovery cycle, and we aborted the previous
995 cycle before recovering this master value */
996
997 log_limit(ls, "dlm_master_lookup from_master %d "
998 "master_nodeid %d res_nodeid %d first %x %s",
999 from_nodeid, r->res_master_nodeid, r->res_nodeid,
1000 r->res_first_lkid, r->res_name);
1001
1002 if (r->res_master_nodeid == our_nodeid) {
1003 log_error(ls, "from_master %d our_master", from_nodeid);
1004 dlm_dump_rsb(r);
1005 dlm_send_rcom_lookup_dump(r, from_nodeid);
1006 goto out_found;
1007 }
1008
1009 r->res_master_nodeid = from_nodeid;
1010 r->res_nodeid = from_nodeid;
1011 rsb_set_flag(r, RSB_NEW_MASTER);
1012 }
1013
1014 if (!r->res_master_nodeid) {
1015 /* this will happen if recovery happens while we're looking
1016 up the master for this rsb */
1017
1018 log_debug(ls, "dlm_master_lookup master 0 to %d first %x %s",
1019 from_nodeid, r->res_first_lkid, r->res_name);
1020 r->res_master_nodeid = from_nodeid;
1021 r->res_nodeid = from_nodeid;
1022 }
1023
1024 if (!from_master && !fix_master &&
1025 (r->res_master_nodeid == from_nodeid)) {
1026 /* this can happen when the master sends remove, the dir node
1027 finds the rsb on the keep list and ignores the remove,
1028 and the former master sends a lookup */
1029
1030 log_limit(ls, "dlm_master_lookup from master %d flags %x "
1031 "first %x %s", from_nodeid, flags,
1032 r->res_first_lkid, r->res_name);
1033 }
1034
1035 out_found:
1036 *r_nodeid = r->res_master_nodeid;
1037 if (result)
1038 *result = DLM_LU_MATCH;
1039
1040 if (toss_list) {
1041 r->res_toss_time = jiffies;
1042 /* the rsb was inactive (on toss list) */
1043 spin_unlock(&ls->ls_rsbtbl[b].lock);
1044 } else {
1045 /* the rsb was active */
1046 unlock_rsb(r);
1047 put_rsb(r);
1048 }
1049 return 0;
e7fd4179 1050
c04fecb4
DT		 1051 not_found:
1052 error = get_rsb_struct(ls, name, len, &r);
3881ac04 1053 if (error == -EAGAIN) {
c04fecb4 1054 spin_unlock(&ls->ls_rsbtbl[b].lock);
3881ac04
DT		 1055 goto retry;
1056 }
1057 if (error)
1058 goto out_unlock;
e7fd4179
DT		 1059
1060 r->res_hash = hash;
c04fecb4
DT		 1061 r->res_bucket = b;
1062 r->res_dir_nodeid = our_nodeid;
1063 r->res_master_nodeid = from_nodeid;
1064 r->res_nodeid = from_nodeid;
e7fd4179 1065 kref_init(&r->res_ref);
c04fecb4 1066 r->res_toss_time = jiffies;
e7fd4179 1067
c04fecb4
DT		 1068 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1069 if (error) {
1070 /* should never happen */
1071 dlm_free_rsb(r);
1072 spin_unlock(&ls->ls_rsbtbl[b].lock);
1073 goto retry;
e7fd4179 1074 }
c04fecb4
DT		 1075
1076 if (result)
1077 *result = DLM_LU_ADD;
1078 *r_nodeid = from_nodeid;
1079 error = 0;
3881ac04 1080 out_unlock:
c04fecb4 1081 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1082 return error;
1083}
1084
6d40c4a7
DT		 1085static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1086{
1087 struct rb_node *n;
1088 struct dlm_rsb *r;
1089 int i;
1090
1091 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1092 spin_lock(&ls->ls_rsbtbl[i].lock);
1093 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1094 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1095 if (r->res_hash == hash)
1096 dlm_dump_rsb(r);
1097 }
1098 spin_unlock(&ls->ls_rsbtbl[i].lock);
1099 }
1100}
1101
c04fecb4 1102void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len)
e7fd4179 1103{
c04fecb4
DT		 1104 struct dlm_rsb *r = NULL;
1105 uint32_t hash, b;
1106 int error;
e7fd4179 1107
c04fecb4
DT		 1108 hash = jhash(name, len, 0);
1109 b = hash & (ls->ls_rsbtbl_size - 1);
1110
1111 spin_lock(&ls->ls_rsbtbl[b].lock);
1112 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1113 if (!error)
1114 goto out_dump;
1115
1116 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1117 if (error)
1118 goto out;
1119 out_dump:
1120 dlm_dump_rsb(r);
1121 out:
1122 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1123}
1124
1125static void toss_rsb(struct kref *kref)
1126{
1127 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1128 struct dlm_ls *ls = r->res_ls;
1129
1130 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1131 kref_init(&r->res_ref);
9beb3bf5
BP		 1132 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1133 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
e7fd4179
DT		 1134 r->res_toss_time = jiffies;
1135 if (r->res_lvbptr) {
52bda2b5 1136 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 1137 r->res_lvbptr = NULL;
1138 }
1139}
1140
e7fd4179
DT		 1141/* See comment for unhold_lkb */
1142
1143static void unhold_rsb(struct dlm_rsb *r)
1144{
1145 int rv;
1146 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 1147 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 1148}
1149
1150static void kill_rsb(struct kref *kref)
1151{
1152 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1153
1154 /* All work is done after the return from kref_put() so we
1155 can release the write_lock before the remove and free. */
1156
a345da3e
DT		 1157 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1158 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1159 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1160 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1161 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1162 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 1163}
1164
1165/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1166 The rsb must exist as long as any lkb's for it do. */
1167
1168static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1169{
1170 hold_rsb(r);
1171 lkb->lkb_resource = r;
1172}
1173
1174static void detach_lkb(struct dlm_lkb *lkb)
1175{
1176 if (lkb->lkb_resource) {
1177 put_rsb(lkb->lkb_resource);
1178 lkb->lkb_resource = NULL;
1179 }
1180}
1181
1182static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1183{
3d6aa675
DT		 1184 struct dlm_lkb *lkb;
1185 int rv, id;
e7fd4179 1186
52bda2b5 1187 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 1188 if (!lkb)
1189 return -ENOMEM;
1190
1191 lkb->lkb_nodeid = -1;
1192 lkb->lkb_grmode = DLM_LOCK_IV;
1193 kref_init(&lkb->lkb_ref);
34e22bed 1194 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 1195 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 1196 INIT_LIST_HEAD(&lkb->lkb_time_list);
23e8e1aa
DT		 1197 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1198 mutex_init(&lkb->lkb_cb_mutex);
1199 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
e7fd4179 1200
3d6aa675
DT		 1201 retry:
1202 rv = idr_pre_get(&ls->ls_lkbidr, GFP_NOFS);
1203 if (!rv)
1204 return -ENOMEM;
e7fd4179 1205
3d6aa675
DT		 1206 spin_lock(&ls->ls_lkbidr_spin);
1207 rv = idr_get_new_above(&ls->ls_lkbidr, lkb, 1, &id);
1208 if (!rv)
1209 lkb->lkb_id = id;
1210 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179 1211
3d6aa675
DT		 1212 if (rv == -EAGAIN)
1213 goto retry;
e7fd4179 1214
3d6aa675
DT		 1215 if (rv < 0) {
1216 log_error(ls, "create_lkb idr error %d", rv);
1217 return rv;
e7fd4179
DT		 1218 }
1219
e7fd4179
DT		 1220 *lkb_ret = lkb;
1221 return 0;
1222}
1223
e7fd4179
DT		 1224static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1225{
1226 struct dlm_lkb *lkb;
e7fd4179 1227
3d6aa675
DT		 1228 spin_lock(&ls->ls_lkbidr_spin);
1229 lkb = idr_find(&ls->ls_lkbidr, lkid);
e7fd4179
DT		 1230 if (lkb)
1231 kref_get(&lkb->lkb_ref);
3d6aa675 1232 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1233
1234 *lkb_ret = lkb;
1235 return lkb ? 0 : -ENOENT;
1236}
1237
1238static void kill_lkb(struct kref *kref)
1239{
1240 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1241
1242 /* All work is done after the return from kref_put() so we
1243 can release the write_lock before the detach_lkb */
1244
1245 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1246}
1247
b3f58d8f
DT		 1248/* __put_lkb() is used when an lkb may not have an rsb attached to
1249 it so we need to provide the lockspace explicitly */
1250
1251static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 1252{
3d6aa675 1253 uint32_t lkid = lkb->lkb_id;
e7fd4179 1254
3d6aa675 1255 spin_lock(&ls->ls_lkbidr_spin);
e7fd4179 1256 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
3d6aa675
DT		 1257 idr_remove(&ls->ls_lkbidr, lkid);
1258 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1259
1260 detach_lkb(lkb);
1261
1262 /* for local/process lkbs, lvbptr points to caller's lksb */
1263 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 1264 dlm_free_lvb(lkb->lkb_lvbptr);
1265 dlm_free_lkb(lkb);
e7fd4179
DT		 1266 return 1;
1267 } else {
3d6aa675 1268 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1269 return 0;
1270 }
1271}
1272
1273int dlm_put_lkb(struct dlm_lkb *lkb)
1274{
b3f58d8f
DT		 1275 struct dlm_ls *ls;
1276
1277 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1278 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1279
1280 ls = lkb->lkb_resource->res_ls;
1281 return __put_lkb(ls, lkb);
e7fd4179
DT		 1282}
1283
1284/* This is only called to add a reference when the code already holds
1285 a valid reference to the lkb, so there's no need for locking. */
1286
1287static inline void hold_lkb(struct dlm_lkb *lkb)
1288{
1289 kref_get(&lkb->lkb_ref);
1290}
1291
1292/* This is called when we need to remove a reference and are certain
1293 it's not the last ref. e.g. del_lkb is always called between a
1294 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1295 put_lkb would work fine, but would involve unnecessary locking */
1296
1297static inline void unhold_lkb(struct dlm_lkb *lkb)
1298{
1299 int rv;
1300 rv = kref_put(&lkb->lkb_ref, kill_lkb);
1301 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
1302}
1303
1304static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1305 int mode)
1306{
1307 struct dlm_lkb *lkb = NULL;
1308
1309 list_for_each_entry(lkb, head, lkb_statequeue)
1310 if (lkb->lkb_rqmode < mode)
1311 break;
1312
99fb19d4 1313 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
e7fd4179
DT		 1314}
1315
1316/* add/remove lkb to rsb's grant/convert/wait queue */
1317
1318static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1319{
1320 kref_get(&lkb->lkb_ref);
1321
1322 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1323
eeda418d
DT		 1324 lkb->lkb_timestamp = ktime_get();
1325
e7fd4179
DT		 1326 lkb->lkb_status = status;
1327
1328 switch (status) {
1329 case DLM_LKSTS_WAITING:
1330 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1331 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1332 else
1333 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1334 break;
1335 case DLM_LKSTS_GRANTED:
1336 /* convention says granted locks kept in order of grmode */
1337 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1338 lkb->lkb_grmode);
1339 break;
1340 case DLM_LKSTS_CONVERT:
1341 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1342 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1343 else
1344 list_add_tail(&lkb->lkb_statequeue,
1345 &r->res_convertqueue);
1346 break;
1347 default:
1348 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1349 }
1350}
1351
1352static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1353{
1354 lkb->lkb_status = 0;
1355 list_del(&lkb->lkb_statequeue);
1356 unhold_lkb(lkb);
1357}
1358
1359static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1360{
1361 hold_lkb(lkb);
1362 del_lkb(r, lkb);
1363 add_lkb(r, lkb, sts);
1364 unhold_lkb(lkb);
1365}
1366
ef0c2bb0
DT		 1367static int msg_reply_type(int mstype)
1368{
1369 switch (mstype) {
1370 case DLM_MSG_REQUEST:
1371 return DLM_MSG_REQUEST_REPLY;
1372 case DLM_MSG_CONVERT:
1373 return DLM_MSG_CONVERT_REPLY;
1374 case DLM_MSG_UNLOCK:
1375 return DLM_MSG_UNLOCK_REPLY;
1376 case DLM_MSG_CANCEL:
1377 return DLM_MSG_CANCEL_REPLY;
1378 case DLM_MSG_LOOKUP:
1379 return DLM_MSG_LOOKUP_REPLY;
1380 }
1381 return -1;
1382}
1383
c6ff669b
DT		 1384static int nodeid_warned(int nodeid, int num_nodes, int *warned)
1385{
1386 int i;
1387
1388 for (i = 0; i < num_nodes; i++) {
1389 if (!warned[i]) {
1390 warned[i] = nodeid;
1391 return 0;
1392 }
1393 if (warned[i] == nodeid)
1394 return 1;
1395 }
1396 return 0;
1397}
1398
1399void dlm_scan_waiters(struct dlm_ls *ls)
1400{
1401 struct dlm_lkb *lkb;
1402 ktime_t zero = ktime_set(0, 0);
1403 s64 us;
1404 s64 debug_maxus = 0;
1405 u32 debug_scanned = 0;
1406 u32 debug_expired = 0;
1407 int num_nodes = 0;
1408 int *warned = NULL;
1409
1410 if (!dlm_config.ci_waitwarn_us)
1411 return;
1412
1413 mutex_lock(&ls->ls_waiters_mutex);
1414
1415 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1416 if (ktime_equal(lkb->lkb_wait_time, zero))
1417 continue;
1418
1419 debug_scanned++;
1420
1421 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
1422
1423 if (us < dlm_config.ci_waitwarn_us)
1424 continue;
1425
1426 lkb->lkb_wait_time = zero;
1427
1428 debug_expired++;
1429 if (us > debug_maxus)
1430 debug_maxus = us;
1431
1432 if (!num_nodes) {
1433 num_nodes = ls->ls_num_nodes;
5d70828a 1434 warned = kzalloc(num_nodes * sizeof(int), GFP_KERNEL);
c6ff669b
DT		 1435 }
1436 if (!warned)
1437 continue;
1438 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
1439 continue;
1440
1441 log_error(ls, "waitwarn %x %lld %d us check connection to "
1442 "node %d", lkb->lkb_id, (long long)us,
1443 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
1444 }
1445 mutex_unlock(&ls->ls_waiters_mutex);
5d70828a 1446 kfree(warned);
c6ff669b
DT		 1447
1448 if (debug_expired)
1449 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
1450 debug_scanned, debug_expired,
1451 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
1452}
1453
e7fd4179
DT		 1454/* add/remove lkb from global waiters list of lkb's waiting for
1455 a reply from a remote node */
1456
c6ff669b 1457static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
e7fd4179
DT		 1458{
1459 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 1460 int error = 0;
e7fd4179 1461
90135925 1462 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 1463
1464 if (is_overlap_unlock(lkb) ||
1465 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1466 error = -EINVAL;
1467 goto out;
1468 }
1469
1470 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1471 switch (mstype) {
1472 case DLM_MSG_UNLOCK:
1473 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
1474 break;
1475 case DLM_MSG_CANCEL:
1476 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
1477 break;
1478 default:
1479 error = -EBUSY;
1480 goto out;
1481 }
1482 lkb->lkb_wait_count++;
1483 hold_lkb(lkb);
1484
43279e53 1485 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
ef0c2bb0
DT		 1486 lkb->lkb_id, lkb->lkb_wait_type, mstype,
1487 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 1488 goto out;
1489 }
ef0c2bb0
DT		 1490
1491 DLM_ASSERT(!lkb->lkb_wait_count,
1492 dlm_print_lkb(lkb);
1493 printk("wait_count %d\n", lkb->lkb_wait_count););
1494
1495 lkb->lkb_wait_count++;
e7fd4179 1496 lkb->lkb_wait_type = mstype;
c6ff669b
DT		 1497 lkb->lkb_wait_time = ktime_get();
1498 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
ef0c2bb0 1499 hold_lkb(lkb);
e7fd4179
DT		 1500 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1501 out:
ef0c2bb0 1502 if (error)
43279e53 1503 log_error(ls, "addwait error %x %d flags %x %d %d %s",
ef0c2bb0
DT		 1504 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1505 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 1506 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 1507 return error;
e7fd4179
DT		 1508}
1509
b790c3b7
DT		 1510/* We clear the RESEND flag because we might be taking an lkb off the waiters
1511 list as part of process_requestqueue (e.g. a lookup that has an optimized
1512 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1513 set RESEND and dlm_recover_waiters_post() */
1514
43279e53
DT		 1515static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1516 struct dlm_message *ms)
e7fd4179 1517{
ef0c2bb0
DT		 1518 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1519 int overlap_done = 0;
e7fd4179 1520
ef0c2bb0 1521 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
43279e53 1522 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1523 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1524 overlap_done = 1;
1525 goto out_del;
e7fd4179 1526 }
ef0c2bb0
DT		 1527
1528 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
43279e53 1529 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1530 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1531 overlap_done = 1;
1532 goto out_del;
1533 }
1534
43279e53
DT		 1535 /* Cancel state was preemptively cleared by a successful convert,
1536 see next comment, nothing to do. */
1537
1538 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1539 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1540 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1541 lkb->lkb_id, lkb->lkb_wait_type);
1542 return -1;
1543 }
1544
1545 /* Remove for the convert reply, and premptively remove for the
1546 cancel reply. A convert has been granted while there's still
1547 an outstanding cancel on it (the cancel is moot and the result
1548 in the cancel reply should be 0). We preempt the cancel reply
1549 because the app gets the convert result and then can follow up
1550 with another op, like convert. This subsequent op would see the
1551 lingering state of the cancel and fail with -EBUSY. */
1552
1553 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1554 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1555 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1556 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1557 lkb->lkb_id);
1558 lkb->lkb_wait_type = 0;
1559 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1560 lkb->lkb_wait_count--;
1561 goto out_del;
1562 }
1563
ef0c2bb0
DT		 1564 /* N.B. type of reply may not always correspond to type of original
1565 msg due to lookup->request optimization, verify others? */
1566
1567 if (lkb->lkb_wait_type) {
1568 lkb->lkb_wait_type = 0;
1569 goto out_del;
1570 }
1571
6d40c4a7
DT		 1572 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1573 lkb->lkb_id, ms ? ms->m_header.h_nodeid : 0, lkb->lkb_remid,
1574 mstype, lkb->lkb_flags);
ef0c2bb0
DT		 1575 return -1;
1576
1577 out_del:
1578 /* the force-unlock/cancel has completed and we haven't recvd a reply
1579 to the op that was in progress prior to the unlock/cancel; we
1580 give up on any reply to the earlier op. FIXME: not sure when/how
1581 this would happen */
1582
1583 if (overlap_done && lkb->lkb_wait_type) {
43279e53 1584 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
ef0c2bb0
DT		 1585 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1586 lkb->lkb_wait_count--;
1587 lkb->lkb_wait_type = 0;
1588 }
1589
1590 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1591
b790c3b7 1592 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 1593 lkb->lkb_wait_count--;
1594 if (!lkb->lkb_wait_count)
1595 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 1596 unhold_lkb(lkb);
ef0c2bb0 1597 return 0;
e7fd4179
DT		 1598}
1599
ef0c2bb0 1600static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 1601{
1602 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1603 int error;
1604
90135925 1605 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1606 error = _remove_from_waiters(lkb, mstype, NULL);
90135925 1607 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 1608 return error;
1609}
1610
ef0c2bb0
DT		 1611/* Handles situations where we might be processing a "fake" or "stub" reply in
1612 which we can't try to take waiters_mutex again. */
1613
1614static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1615{
1616 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1617 int error;
1618
2a7ce0ed 1619 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0 1620 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1621 error = _remove_from_waiters(lkb, ms->m_type, ms);
2a7ce0ed 1622 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0
DT		 1623 mutex_unlock(&ls->ls_waiters_mutex);
1624 return error;
1625}
1626
05c32f47
DT		 1627/* If there's an rsb for the same resource being removed, ensure
1628 that the remove message is sent before the new lookup message.
1629 It should be rare to need a delay here, but if not, then it may
1630 be worthwhile to add a proper wait mechanism rather than a delay. */
e7fd4179 1631
05c32f47 1632static void wait_pending_remove(struct dlm_rsb *r)
e7fd4179 1633{
05c32f47
DT		 1634 struct dlm_ls *ls = r->res_ls;
1635 restart:
1636 spin_lock(&ls->ls_remove_spin);
1637 if (ls->ls_remove_len &&
1638 !rsb_cmp(r, ls->ls_remove_name, ls->ls_remove_len)) {
1639 log_debug(ls, "delay lookup for remove dir %d %s",
1640 r->res_dir_nodeid, r->res_name);
1641 spin_unlock(&ls->ls_remove_spin);
1642 msleep(1);
1643 goto restart;
1644 }
1645 spin_unlock(&ls->ls_remove_spin);
1646}
e7fd4179 1647
05c32f47
DT		 1648/*
1649 * ls_remove_spin protects ls_remove_name and ls_remove_len which are
1650 * read by other threads in wait_pending_remove. ls_remove_names
1651 * and ls_remove_lens are only used by the scan thread, so they do
1652 * not need protection.
1653 */
c04fecb4 1654
05c32f47
DT		 1655static void shrink_bucket(struct dlm_ls *ls, int b)
1656{
1657 struct rb_node *n, *next;
1658 struct dlm_rsb *r;
1659 char *name;
1660 int our_nodeid = dlm_our_nodeid();
1661 int remote_count = 0;
1662 int i, len, rv;
c04fecb4 1663
05c32f47 1664 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
c04fecb4 1665
05c32f47
DT		 1666 spin_lock(&ls->ls_rsbtbl[b].lock);
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;
e7fd4179
DT		 1680 }
1681
05c32f47
DT		 1682 if (!time_after_eq(jiffies, r->res_toss_time +
1683 dlm_config.ci_toss_secs * HZ)) {
1684 continue;
e7fd4179
DT		 1685 }
1686
05c32f47
DT		 1687 if (!dlm_no_directory(ls) &&
1688 (r->res_master_nodeid == our_nodeid) &&
1689 (dlm_dir_nodeid(r) != our_nodeid)) {
e7fd4179 1690
c04fecb4
DT		 1691 /* We're the master of this rsb but we're not
1692 the directory record, so we need to tell the
1693 dir node to remove the dir record. */
1694
05c32f47
DT		 1695 ls->ls_remove_lens[remote_count] = r->res_length;
1696 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1697 DLM_RESNAME_MAXLEN);
1698 remote_count++;
c04fecb4 1699
05c32f47
DT		 1700 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1701 break;
1702 continue;
1703 }
1704
1705 if (!kref_put(&r->res_ref, kill_rsb)) {
e7fd4179 1706 log_error(ls, "tossed rsb in use %s", r->res_name);
05c32f47 1707 continue;
e7fd4179 1708 }
05c32f47
DT		 1709
1710 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1711 dlm_free_rsb(r);
e7fd4179 1712 }
05c32f47 1713 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179 1714
05c32f47
DT		 1715 /*
1716 * While searching for rsb's to free, we found some that require
1717 * remote removal. We leave them in place and find them again here
1718 * so there is a very small gap between removing them from the toss
1719 * list and sending the removal. Keeping this gap small is
1720 * important to keep us (the master node) from being out of sync
1721 * with the remote dir node for very long.
1722 *
1723 * From the time the rsb is removed from toss until just after
1724 * send_remove, the rsb name is saved in ls_remove_name. A new
1725 * lookup checks this to ensure that a new lookup message for the
1726 * same resource name is not sent just before the remove message.
1727 */
1728
1729 for (i = 0; i < remote_count; i++) {
1730 name = ls->ls_remove_names[i];
1731 len = ls->ls_remove_lens[i];
1732
1733 spin_lock(&ls->ls_rsbtbl[b].lock);
1734 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1735 if (rv) {
1736 spin_unlock(&ls->ls_rsbtbl[b].lock);
1737 log_debug(ls, "remove_name not toss %s", name);
1738 continue;
1739 }
1740
1741 if (r->res_master_nodeid != our_nodeid) {
1742 spin_unlock(&ls->ls_rsbtbl[b].lock);
1743 log_debug(ls, "remove_name master %d dir %d our %d %s",
1744 r->res_master_nodeid, r->res_dir_nodeid,
1745 our_nodeid, name);
1746 continue;
1747 }
1748
1749 if (r->res_dir_nodeid == our_nodeid) {
1750 /* should never happen */
1751 spin_unlock(&ls->ls_rsbtbl[b].lock);
1752 log_error(ls, "remove_name dir %d master %d our %d %s",
1753 r->res_dir_nodeid, r->res_master_nodeid,
1754 our_nodeid, name);
1755 continue;
1756 }
1757
1758 if (!time_after_eq(jiffies, r->res_toss_time +
1759 dlm_config.ci_toss_secs * HZ)) {
1760 spin_unlock(&ls->ls_rsbtbl[b].lock);
1761 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1762 r->res_toss_time, jiffies, name);
1763 continue;
1764 }
1765
1766 if (!kref_put(&r->res_ref, kill_rsb)) {
1767 spin_unlock(&ls->ls_rsbtbl[b].lock);
1768 log_error(ls, "remove_name in use %s", name);
1769 continue;
1770 }
1771
1772 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1773
1774 /* block lookup of same name until we've sent remove */
1775 spin_lock(&ls->ls_remove_spin);
1776 ls->ls_remove_len = len;
1777 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
1778 spin_unlock(&ls->ls_remove_spin);
1779 spin_unlock(&ls->ls_rsbtbl[b].lock);
1780
1781 send_remove(r);
1782
1783 /* allow lookup of name again */
1784 spin_lock(&ls->ls_remove_spin);
1785 ls->ls_remove_len = 0;
1786 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
1787 spin_unlock(&ls->ls_remove_spin);
1788
1789 dlm_free_rsb(r);
1790 }
e7fd4179
DT		 1791}
1792
1793void dlm_scan_rsbs(struct dlm_ls *ls)
1794{
1795 int i;
1796
e7fd4179
DT		 1797 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1798 shrink_bucket(ls, i);
85e86edf
DT		 1799 if (dlm_locking_stopped(ls))
1800 break;
e7fd4179
DT		 1801 cond_resched();
1802 }
1803}
1804
3ae1acf9
DT		 1805static void add_timeout(struct dlm_lkb *lkb)
1806{
1807 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1808
eeda418d 1809 if (is_master_copy(lkb))
3ae1acf9 1810 return;
3ae1acf9
DT		 1811
1812 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1813 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1814 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1815 goto add_it;
1816 }
84d8cd69
DT		 1817 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1818 goto add_it;
3ae1acf9
DT		 1819 return;
1820
1821 add_it:
1822 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1823 mutex_lock(&ls->ls_timeout_mutex);
1824 hold_lkb(lkb);
3ae1acf9
DT		 1825 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1826 mutex_unlock(&ls->ls_timeout_mutex);
1827}
1828
1829static void del_timeout(struct dlm_lkb *lkb)
1830{
1831 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1832
1833 mutex_lock(&ls->ls_timeout_mutex);
1834 if (!list_empty(&lkb->lkb_time_list)) {
1835 list_del_init(&lkb->lkb_time_list);
1836 unhold_lkb(lkb);
1837 }
1838 mutex_unlock(&ls->ls_timeout_mutex);
1839}
1840
1841/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1842 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1843 and then lock rsb because of lock ordering in add_timeout. We may need
1844 to specify some special timeout-related bits in the lkb that are just to
1845 be accessed under the timeout_mutex. */
1846
1847void dlm_scan_timeout(struct dlm_ls *ls)
1848{
1849 struct dlm_rsb *r;
1850 struct dlm_lkb *lkb;
1851 int do_cancel, do_warn;
eeda418d 1852 s64 wait_us;
3ae1acf9
DT		 1853
1854 for (;;) {
1855 if (dlm_locking_stopped(ls))
1856 break;
1857
1858 do_cancel = 0;
1859 do_warn = 0;
1860 mutex_lock(&ls->ls_timeout_mutex);
1861 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1862
eeda418d
DT		 1863 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1864 lkb->lkb_timestamp));
1865
3ae1acf9 1866 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
eeda418d 1867 wait_us >= (lkb->lkb_timeout_cs * 10000))
3ae1acf9
DT		 1868 do_cancel = 1;
1869
1870 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
eeda418d 1871 wait_us >= dlm_config.ci_timewarn_cs * 10000)
3ae1acf9
DT		 1872 do_warn = 1;
1873
1874 if (!do_cancel && !do_warn)
1875 continue;
1876 hold_lkb(lkb);
1877 break;
1878 }
1879 mutex_unlock(&ls->ls_timeout_mutex);
1880
1881 if (!do_cancel && !do_warn)
1882 break;
1883
1884 r = lkb->lkb_resource;
1885 hold_rsb(r);
1886 lock_rsb(r);
1887
1888 if (do_warn) {
1889 /* clear flag so we only warn once */
1890 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1891 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1892 del_timeout(lkb);
1893 dlm_timeout_warn(lkb);
1894 }
1895
1896 if (do_cancel) {
b3cab7b9 1897 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1898 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1899 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1900 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1901 del_timeout(lkb);
1902 _cancel_lock(r, lkb);
1903 }
1904
1905 unlock_rsb(r);
1906 unhold_rsb(r);
1907 dlm_put_lkb(lkb);
1908 }
1909}
1910
1911/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1912 dlm_recoverd before checking/setting ls_recover_begin. */
1913
1914void dlm_adjust_timeouts(struct dlm_ls *ls)
1915{
1916 struct dlm_lkb *lkb;
eeda418d 1917 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
3ae1acf9
DT		 1918
1919 ls->ls_recover_begin = 0;
1920 mutex_lock(&ls->ls_timeout_mutex);
1921 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
eeda418d 1922 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
3ae1acf9 1923 mutex_unlock(&ls->ls_timeout_mutex);
c6ff669b
DT		 1924
1925 if (!dlm_config.ci_waitwarn_us)
1926 return;
1927
1928 mutex_lock(&ls->ls_waiters_mutex);
1929 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1930 if (ktime_to_us(lkb->lkb_wait_time))
1931 lkb->lkb_wait_time = ktime_get();
1932 }
1933 mutex_unlock(&ls->ls_waiters_mutex);
3ae1acf9
DT		 1934}
1935
e7fd4179
DT		 1936/* lkb is master or local copy */
1937
1938static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1939{
1940 int b, len = r->res_ls->ls_lvblen;
1941
1942 /* b=1 lvb returned to caller
1943 b=0 lvb written to rsb or invalidated
1944 b=-1 do nothing */
1945
1946 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1947
1948 if (b == 1) {
1949 if (!lkb->lkb_lvbptr)
1950 return;
1951
1952 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1953 return;
1954
1955 if (!r->res_lvbptr)
1956 return;
1957
1958 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1959 lkb->lkb_lvbseq = r->res_lvbseq;
1960
1961 } else if (b == 0) {
1962 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1963 rsb_set_flag(r, RSB_VALNOTVALID);
1964 return;
1965 }
1966
1967 if (!lkb->lkb_lvbptr)
1968 return;
1969
1970 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1971 return;
1972
1973 if (!r->res_lvbptr)
52bda2b5 1974 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1975
1976 if (!r->res_lvbptr)
1977 return;
1978
1979 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1980 r->res_lvbseq++;
1981 lkb->lkb_lvbseq = r->res_lvbseq;
1982 rsb_clear_flag(r, RSB_VALNOTVALID);
1983 }
1984
1985 if (rsb_flag(r, RSB_VALNOTVALID))
1986 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1987}
1988
1989static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1990{
1991 if (lkb->lkb_grmode < DLM_LOCK_PW)
1992 return;
1993
1994 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1995 rsb_set_flag(r, RSB_VALNOTVALID);
1996 return;
1997 }
1998
1999 if (!lkb->lkb_lvbptr)
2000 return;
2001
2002 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2003 return;
2004
2005 if (!r->res_lvbptr)
52bda2b5 2006 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 2007
2008 if (!r->res_lvbptr)
2009 return;
2010
2011 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2012 r->res_lvbseq++;
2013 rsb_clear_flag(r, RSB_VALNOTVALID);
2014}
2015
2016/* lkb is process copy (pc) */
2017
2018static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2019 struct dlm_message *ms)
2020{
2021 int b;
2022
2023 if (!lkb->lkb_lvbptr)
2024 return;
2025
2026 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2027 return;
2028
597d0cae 2029 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 2030 if (b == 1) {
2031 int len = receive_extralen(ms);
a9cc9159
AV		 2032 if (len > DLM_RESNAME_MAXLEN)
2033 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 2034 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
2035 lkb->lkb_lvbseq = ms->m_lvbseq;
2036 }
2037}
2038
2039/* Manipulate lkb's on rsb's convert/granted/waiting queues
2040 remove_lock -- used for unlock, removes lkb from granted
2041 revert_lock -- used for cancel, moves lkb from convert to granted
2042 grant_lock -- used for request and convert, adds lkb to granted or
2043 moves lkb from convert or waiting to granted
2044
2045 Each of these is used for master or local copy lkb's. There is
2046 also a _pc() variation used to make the corresponding change on
2047 a process copy (pc) lkb. */
2048
2049static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2050{
2051 del_lkb(r, lkb);
2052 lkb->lkb_grmode = DLM_LOCK_IV;
2053 /* this unhold undoes the original ref from create_lkb()
2054 so this leads to the lkb being freed */
2055 unhold_lkb(lkb);
2056}
2057
2058static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2059{
2060 set_lvb_unlock(r, lkb);
2061 _remove_lock(r, lkb);
2062}
2063
2064static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2065{
2066 _remove_lock(r, lkb);
2067}
2068
ef0c2bb0
DT		 2069/* returns: 0 did nothing
2070 1 moved lock to granted
2071 -1 removed lock */
2072
2073static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2074{
ef0c2bb0
DT		 2075 int rv = 0;
2076
e7fd4179
DT		 2077 lkb->lkb_rqmode = DLM_LOCK_IV;
2078
2079 switch (lkb->lkb_status) {
597d0cae
DT		 2080 case DLM_LKSTS_GRANTED:
2081 break;
e7fd4179
DT		 2082 case DLM_LKSTS_CONVERT:
2083 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 2084 rv = 1;
e7fd4179
DT		 2085 break;
2086 case DLM_LKSTS_WAITING:
2087 del_lkb(r, lkb);
2088 lkb->lkb_grmode = DLM_LOCK_IV;
2089 /* this unhold undoes the original ref from create_lkb()
2090 so this leads to the lkb being freed */
2091 unhold_lkb(lkb);
ef0c2bb0 2092 rv = -1;
e7fd4179
DT		 2093 break;
2094 default:
2095 log_print("invalid status for revert %d", lkb->lkb_status);
2096 }
ef0c2bb0 2097 return rv;
e7fd4179
DT		 2098}
2099
ef0c2bb0 2100static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2101{
ef0c2bb0 2102 return revert_lock(r, lkb);
e7fd4179
DT		 2103}
2104
2105static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2106{
2107 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
2108 lkb->lkb_grmode = lkb->lkb_rqmode;
2109 if (lkb->lkb_status)
2110 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2111 else
2112 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
2113 }
2114
2115 lkb->lkb_rqmode = DLM_LOCK_IV;
4875647a 2116 lkb->lkb_highbast = 0;
e7fd4179
DT		 2117}
2118
2119static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2120{
2121 set_lvb_lock(r, lkb);
2122 _grant_lock(r, lkb);
e7fd4179
DT		 2123}
2124
2125static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2126 struct dlm_message *ms)
2127{
2128 set_lvb_lock_pc(r, lkb, ms);
2129 _grant_lock(r, lkb);
2130}
2131
2132/* called by grant_pending_locks() which means an async grant message must
2133 be sent to the requesting node in addition to granting the lock if the
2134 lkb belongs to a remote node. */
2135
2136static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
2137{
2138 grant_lock(r, lkb);
2139 if (is_master_copy(lkb))
2140 send_grant(r, lkb);
2141 else
2142 queue_cast(r, lkb, 0);
2143}
2144
7d3c1feb
DT		 2145/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
2146 change the granted/requested modes. We're munging things accordingly in
2147 the process copy.
2148 CONVDEADLK: our grmode may have been forced down to NL to resolve a
2149 conversion deadlock
2150 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
2151 compatible with other granted locks */
2152
2a7ce0ed 2153static void munge_demoted(struct dlm_lkb *lkb)
7d3c1feb 2154{
7d3c1feb
DT		 2155 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
2156 log_print("munge_demoted %x invalid modes gr %d rq %d",
2157 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
2158 return;
2159 }
2160
2161 lkb->lkb_grmode = DLM_LOCK_NL;
2162}
2163
2164static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
2165{
2166 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
2167 ms->m_type != DLM_MSG_GRANT) {
2168 log_print("munge_altmode %x invalid reply type %d",
2169 lkb->lkb_id, ms->m_type);
2170 return;
2171 }
2172
2173 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
2174 lkb->lkb_rqmode = DLM_LOCK_PR;
2175 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
2176 lkb->lkb_rqmode = DLM_LOCK_CW;
2177 else {
2178 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
2179 dlm_print_lkb(lkb);
2180 }
2181}
2182
e7fd4179
DT		 2183static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
2184{
2185 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
2186 lkb_statequeue);
2187 if (lkb->lkb_id == first->lkb_id)
90135925 2188 return 1;
e7fd4179 2189
90135925 2190 return 0;
e7fd4179
DT		 2191}
2192
e7fd4179
DT		 2193/* Check if the given lkb conflicts with another lkb on the queue. */
2194
2195static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
2196{
2197 struct dlm_lkb *this;
2198
2199 list_for_each_entry(this, head, lkb_statequeue) {
2200 if (this == lkb)
2201 continue;
3bcd3687 2202 if (!modes_compat(this, lkb))
90135925 2203 return 1;
e7fd4179 2204 }
90135925 2205 return 0;
e7fd4179
DT		 2206}
2207
2208/*
2209 * "A conversion deadlock arises with a pair of lock requests in the converting
2210 * queue for one resource. The granted mode of each lock blocks the requested
2211 * mode of the other lock."
2212 *
c85d65e9
DT		 2213 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
2214 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 2215 *
2216 * Example:
2217 * Granted Queue: empty
2218 * Convert Queue: NL->EX (first lock)
2219 * PR->EX (second lock)
2220 *
2221 * The first lock can't be granted because of the granted mode of the second
2222 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 2223 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2224 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2225 * flag set and return DEMOTED in the lksb flags.
e7fd4179 2226 *
c85d65e9
DT		 2227 * Originally, this function detected conv-deadlk in a more limited scope:
2228 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2229 * - if lkb1 was the first entry in the queue (not just earlier), and was
2230 * blocked by the granted mode of lkb2, and there was nothing on the
2231 * granted queue preventing lkb1 from being granted immediately, i.e.
2232 * lkb2 was the only thing preventing lkb1 from being granted.
2233 *
2234 * That second condition meant we'd only say there was conv-deadlk if
2235 * resolving it (by demotion) would lead to the first lock on the convert
2236 * queue being granted right away. It allowed conversion deadlocks to exist
2237 * between locks on the convert queue while they couldn't be granted anyway.
2238 *
2239 * Now, we detect and take action on conversion deadlocks immediately when
2240 * they're created, even if they may not be immediately consequential. If
2241 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2242 * mode that would prevent lkb1's conversion from being granted, we do a
2243 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2244 * I think this means that the lkb_is_ahead condition below should always
2245 * be zero, i.e. there will never be conv-deadlk between two locks that are
2246 * both already on the convert queue.
e7fd4179
DT		 2247 */
2248
c85d65e9 2249static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 2250{
c85d65e9
DT		 2251 struct dlm_lkb *lkb1;
2252 int lkb_is_ahead = 0;
e7fd4179 2253
c85d65e9
DT		 2254 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2255 if (lkb1 == lkb2) {
2256 lkb_is_ahead = 1;
e7fd4179
DT		 2257 continue;
2258 }
2259
c85d65e9
DT		 2260 if (!lkb_is_ahead) {
2261 if (!modes_compat(lkb2, lkb1))
2262 return 1;
2263 } else {
2264 if (!modes_compat(lkb2, lkb1) &&
2265 !modes_compat(lkb1, lkb2))
2266 return 1;
2267 }
e7fd4179 2268 }
90135925 2269 return 0;
e7fd4179
DT		 2270}
2271
2272/*
2273 * Return 1 if the lock can be granted, 0 otherwise.
2274 * Also detect and resolve conversion deadlocks.
2275 *
2276 * lkb is the lock to be granted
2277 *
2278 * now is 1 if the function is being called in the context of the
2279 * immediate request, it is 0 if called later, after the lock has been
2280 * queued.
2281 *
c503a621
DT		 2282 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2283 * after recovery.
2284 *
e7fd4179
DT		 2285 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2286 */
2287
c503a621
DT		 2288static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2289 int recover)
e7fd4179
DT		 2290{
2291 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2292
2293 /*
2294 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2295 * a new request for a NL mode lock being blocked.
2296 *
2297 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2298 * request, then it would be granted. In essence, the use of this flag
2299 * tells the Lock Manager to expedite theis request by not considering
2300 * what may be in the CONVERTING or WAITING queues... As of this
2301 * writing, the EXPEDITE flag can be used only with new requests for NL
2302 * mode locks. This flag is not valid for conversion requests.
2303 *
2304 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2305 * conversion or used with a non-NL requested mode. We also know an
2306 * EXPEDITE request is always granted immediately, so now must always
2307 * be 1. The full condition to grant an expedite request: (now &&
2308 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2309 * therefore be shortened to just checking the flag.
2310 */
2311
2312 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 2313 return 1;
e7fd4179
DT		 2314
2315 /*
2316 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2317 * added to the remaining conditions.
2318 */
2319
2320 if (queue_conflict(&r->res_grantqueue, lkb))
c503a621 2321 return 0;
e7fd4179
DT		 2322
2323 /*
2324 * 6-3: By default, a conversion request is immediately granted if the
2325 * requested mode is compatible with the modes of all other granted
2326 * locks
2327 */
2328
2329 if (queue_conflict(&r->res_convertqueue, lkb))
c503a621
DT		 2330 return 0;
2331
2332 /*
2333 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2334 * locks for a recovered rsb, on which lkb's have been rebuilt.
2335 * The lkb's may have been rebuilt on the queues in a different
2336 * order than they were in on the previous master. So, granting
2337 * queued conversions in order after recovery doesn't make sense
2338 * since the order hasn't been preserved anyway. The new order
2339 * could also have created a new "in place" conversion deadlock.
2340 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2341 * After recovery, there would be no granted locks, and possibly
2342 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2343 * recovery, grant conversions without considering order.
2344 */
2345
2346 if (conv && recover)
2347 return 1;
e7fd4179
DT		 2348
2349 /*
2350 * 6-5: But the default algorithm for deciding whether to grant or
2351 * queue conversion requests does not by itself guarantee that such
2352 * requests are serviced on a "first come first serve" basis. This, in
2353 * turn, can lead to a phenomenon known as "indefinate postponement".
2354 *
2355 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2356 * the system service employed to request a lock conversion. This flag
2357 * forces certain conversion requests to be queued, even if they are
2358 * compatible with the granted modes of other locks on the same
2359 * resource. Thus, the use of this flag results in conversion requests
2360 * being ordered on a "first come first servce" basis.
2361 *
2362 * DCT: This condition is all about new conversions being able to occur
2363 * "in place" while the lock remains on the granted queue (assuming
2364 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2365 * doesn't _have_ to go onto the convert queue where it's processed in
2366 * order. The "now" variable is necessary to distinguish converts
2367 * being received and processed for the first time now, because once a
2368 * convert is moved to the conversion queue the condition below applies
2369 * requiring fifo granting.
2370 */
2371
2372 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 2373 return 1;
e7fd4179 2374
53ad1c98
DT		 2375 /*
2376 * Even if the convert is compat with all granted locks,
2377 * QUECVT forces it behind other locks on the convert queue.
2378 */
2379
2380 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2381 if (list_empty(&r->res_convertqueue))
2382 return 1;
2383 else
c503a621 2384 return 0;
53ad1c98
DT		 2385 }
2386
e7fd4179 2387 /*
3bcd3687
DT		 2388 * The NOORDER flag is set to avoid the standard vms rules on grant
2389 * order.
e7fd4179
DT		 2390 */
2391
2392 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 2393 return 1;
e7fd4179
DT		 2394
2395 /*
2396 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2397 * granted until all other conversion requests ahead of it are granted
2398 * and/or canceled.
2399 */
2400
2401 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 2402 return 1;
e7fd4179
DT		 2403
2404 /*
2405 * 6-4: By default, a new request is immediately granted only if all
2406 * three of the following conditions are satisfied when the request is
2407 * issued:
2408 * - The queue of ungranted conversion requests for the resource is
2409 * empty.
2410 * - The queue of ungranted new requests for the resource is empty.
2411 * - The mode of the new request is compatible with the most
2412 * restrictive mode of all granted locks on the resource.
2413 */
2414
2415 if (now && !conv && list_empty(&r->res_convertqueue) &&
2416 list_empty(&r->res_waitqueue))
90135925 2417 return 1;
e7fd4179
DT		 2418
2419 /*
2420 * 6-4: Once a lock request is in the queue of ungranted new requests,
2421 * it cannot be granted until the queue of ungranted conversion
2422 * requests is empty, all ungranted new requests ahead of it are
2423 * granted and/or canceled, and it is compatible with the granted mode
2424 * of the most restrictive lock granted on the resource.
2425 */
2426
2427 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2428 first_in_list(lkb, &r->res_waitqueue))
90135925 2429 return 1;
c503a621 2430
90135925 2431 return 0;
e7fd4179
DT		 2432}
2433
c85d65e9 2434static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
c503a621 2435 int recover, int *err)
e7fd4179 2436{
e7fd4179
DT		 2437 int rv;
2438 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 2439 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2440
2441 if (err)
2442 *err = 0;
e7fd4179 2443
c503a621 2444 rv = _can_be_granted(r, lkb, now, recover);
e7fd4179
DT		 2445 if (rv)
2446 goto out;
2447
c85d65e9
DT		 2448 /*
2449 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2450 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2451 * cancels one of the locks.
2452 */
2453
2454 if (is_convert && can_be_queued(lkb) &&
2455 conversion_deadlock_detect(r, lkb)) {
2456 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2457 lkb->lkb_grmode = DLM_LOCK_NL;
2458 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
2459 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
2460 if (err)
2461 *err = -EDEADLK;
2462 else {
2463 log_print("can_be_granted deadlock %x now %d",
2464 lkb->lkb_id, now);
2465 dlm_dump_rsb(r);
2466 }
2467 }
e7fd4179 2468 goto out;
c85d65e9 2469 }
e7fd4179 2470
c85d65e9
DT		 2471 /*
2472 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2473 * to grant a request in a mode other than the normal rqmode. It's a
2474 * simple way to provide a big optimization to applications that can
2475 * use them.
2476 */
2477
2478 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 2479 alt = DLM_LOCK_PR;
c85d65e9 2480 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 2481 alt = DLM_LOCK_CW;
2482
2483 if (alt) {
2484 lkb->lkb_rqmode = alt;
c503a621 2485 rv = _can_be_granted(r, lkb, now, 0);
e7fd4179
DT		 2486 if (rv)
2487 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
2488 else
2489 lkb->lkb_rqmode = rqmode;
2490 }
2491 out:
2492 return rv;
2493}
2494
c85d65e9
DT		 2495/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
2496 for locks pending on the convert list. Once verified (watch for these
2497 log_prints), we should be able to just call _can_be_granted() and not
2498 bother with the demote/deadlk cases here (and there's no easy way to deal
2499 with a deadlk here, we'd have to generate something like grant_lock with
2500 the deadlk error.) */
2501
36509258
DT		 2502/* Returns the highest requested mode of all blocked conversions; sets
2503 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 2504
4875647a
DT		 2505static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2506 unsigned int *count)
e7fd4179
DT		 2507{
2508 struct dlm_lkb *lkb, *s;
c503a621 2509 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
e7fd4179 2510 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 2511 int deadlk;
e7fd4179
DT		 2512
2513 quit = 0;
2514 restart:
2515 grant_restart = 0;
2516 demote_restart = 0;
2517 hi = DLM_LOCK_IV;
2518
2519 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2520 demoted = is_demoted(lkb);
c85d65e9
DT		 2521 deadlk = 0;
2522
c503a621 2523 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
e7fd4179
DT		 2524 grant_lock_pending(r, lkb);
2525 grant_restart = 1;
4875647a
DT		 2526 if (count)
2527 (*count)++;
c85d65e9 2528 continue;
e7fd4179 2529 }
c85d65e9
DT		 2530
2531 if (!demoted && is_demoted(lkb)) {
2532 log_print("WARN: pending demoted %x node %d %s",
2533 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2534 demote_restart = 1;
2535 continue;
2536 }
2537
2538 if (deadlk) {
2539 log_print("WARN: pending deadlock %x node %d %s",
2540 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2541 dlm_dump_rsb(r);
2542 continue;
2543 }
2544
2545 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 2546
2547 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2548 *cw = 1;
e7fd4179
DT		 2549 }
2550
2551 if (grant_restart)
2552 goto restart;
2553 if (demote_restart && !quit) {
2554 quit = 1;
2555 goto restart;
2556 }
2557
2558 return max_t(int, high, hi);
2559}
2560
4875647a
DT		 2561static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2562 unsigned int *count)
e7fd4179
DT		 2563{
2564 struct dlm_lkb *lkb, *s;
2565
2566 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c503a621 2567 if (can_be_granted(r, lkb, 0, 0, NULL)) {
e7fd4179 2568 grant_lock_pending(r, lkb);
4875647a
DT		 2569 if (count)
2570 (*count)++;
2571 } else {
e7fd4179 2572 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 2573 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2574 *cw = 1;
2575 }
e7fd4179
DT		 2576 }
2577
2578 return high;
2579}
2580
36509258
DT		 2581/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2582 on either the convert or waiting queue.
2583 high is the largest rqmode of all locks blocked on the convert or
2584 waiting queue. */
2585
2586static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2587{
2588 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2589 if (gr->lkb_highbast < DLM_LOCK_EX)
2590 return 1;
2591 return 0;
2592 }
2593
2594 if (gr->lkb_highbast < high &&
2595 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2596 return 1;
2597 return 0;
2598}
2599
4875647a 2600static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
e7fd4179
DT		 2601{
2602 struct dlm_lkb *lkb, *s;
2603 int high = DLM_LOCK_IV;
36509258 2604 int cw = 0;
e7fd4179 2605
4875647a
DT		 2606 if (!is_master(r)) {
2607 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2608 dlm_dump_rsb(r);
2609 return;
2610 }
e7fd4179 2611
4875647a
DT		 2612 high = grant_pending_convert(r, high, &cw, count);
2613 high = grant_pending_wait(r, high, &cw, count);
e7fd4179
DT		 2614
2615 if (high == DLM_LOCK_IV)
2616 return;
2617
2618 /*
2619 * If there are locks left on the wait/convert queue then send blocking
2620 * ASTs to granted locks based on the largest requested mode (high)
36509258 2621 * found above.
e7fd4179
DT		 2622 */
2623
2624 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 2625 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
329fc4c3
DT		 2626 if (cw && high == DLM_LOCK_PR &&
2627 lkb->lkb_grmode == DLM_LOCK_PR)
36509258
DT		 2628 queue_bast(r, lkb, DLM_LOCK_CW);
2629 else
2630 queue_bast(r, lkb, high);
e7fd4179
DT		 2631 lkb->lkb_highbast = high;
2632 }
2633 }
2634}
2635
36509258
DT		 2636static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2637{
2638 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2639 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2640 if (gr->lkb_highbast < DLM_LOCK_EX)
2641 return 1;
2642 return 0;
2643 }
2644
2645 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2646 return 1;
2647 return 0;
2648}
2649
e7fd4179
DT		 2650static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2651 struct dlm_lkb *lkb)
2652{
2653 struct dlm_lkb *gr;
2654
2655 list_for_each_entry(gr, head, lkb_statequeue) {
314dd2a0
SW		 2656 /* skip self when sending basts to convertqueue */
2657 if (gr == lkb)
2658 continue;
e5dae548 2659 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 2660 queue_bast(r, gr, lkb->lkb_rqmode);
2661 gr->lkb_highbast = lkb->lkb_rqmode;
2662 }
2663 }
2664}
2665
2666static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2667{
2668 send_bast_queue(r, &r->res_grantqueue, lkb);
2669}
2670
2671static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2672{
2673 send_bast_queue(r, &r->res_grantqueue, lkb);
2674 send_bast_queue(r, &r->res_convertqueue, lkb);
2675}
2676
2677/* set_master(r, lkb) -- set the master nodeid of a resource
2678
2679 The purpose of this function is to set the nodeid field in the given
2680 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2681 known, it can just be copied to the lkb and the function will return
2682 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2683 before it can be copied to the lkb.
2684
2685 When the rsb nodeid is being looked up remotely, the initial lkb
2686 causing the lookup is kept on the ls_waiters list waiting for the
2687 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2688 on the rsb's res_lookup list until the master is verified.
2689
2690 Return values:
2691 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2692 1: the rsb master is not available and the lkb has been placed on
2693 a wait queue
2694*/
2695
2696static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2697{
c04fecb4 2698 int our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 2699
2700 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2701 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2702 r->res_first_lkid = lkb->lkb_id;
2703 lkb->lkb_nodeid = r->res_nodeid;
2704 return 0;
2705 }
2706
2707 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2708 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2709 return 1;
2710 }
2711
c04fecb4 2712 if (r->res_master_nodeid == our_nodeid) {
e7fd4179
DT		 2713 lkb->lkb_nodeid = 0;
2714 return 0;
2715 }
2716
c04fecb4
DT		 2717 if (r->res_master_nodeid) {
2718 lkb->lkb_nodeid = r->res_master_nodeid;
e7fd4179
DT		 2719 return 0;
2720 }
2721
c04fecb4
DT		 2722 if (dlm_dir_nodeid(r) == our_nodeid) {
2723 /* This is a somewhat unusual case; find_rsb will usually
2724 have set res_master_nodeid when dir nodeid is local, but
2725 there are cases where we become the dir node after we've
2726 past find_rsb and go through _request_lock again.
2727 confirm_master() or process_lookup_list() needs to be
2728 called after this. */
2729 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2730 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2731 r->res_name);
2732 r->res_master_nodeid = our_nodeid;
e7fd4179
DT		 2733 r->res_nodeid = 0;
2734 lkb->lkb_nodeid = 0;
c04fecb4 2735 return 0;
e7fd4179 2736 }
c04fecb4 2737
05c32f47
DT		 2738 wait_pending_remove(r);
2739
c04fecb4
DT		 2740 r->res_first_lkid = lkb->lkb_id;
2741 send_lookup(r, lkb);
2742 return 1;
e7fd4179
DT		 2743}
2744
2745static void process_lookup_list(struct dlm_rsb *r)
2746{
2747 struct dlm_lkb *lkb, *safe;
2748
2749 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 2750 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2751 _request_lock(r, lkb);
2752 schedule();
2753 }
2754}
2755
2756/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2757
2758static void confirm_master(struct dlm_rsb *r, int error)
2759{
2760 struct dlm_lkb *lkb;
2761
2762 if (!r->res_first_lkid)
2763 return;
2764
2765 switch (error) {
2766 case 0:
2767 case -EINPROGRESS:
2768 r->res_first_lkid = 0;
2769 process_lookup_list(r);
2770 break;
2771
2772 case -EAGAIN:
aec64e1b
DT		 2773 case -EBADR:
2774 case -ENOTBLK:
2775 /* the remote request failed and won't be retried (it was
2776 a NOQUEUE, or has been canceled/unlocked); make a waiting
2777 lkb the first_lkid */
e7fd4179
DT		 2778
2779 r->res_first_lkid = 0;
2780
2781 if (!list_empty(&r->res_lookup)) {
2782 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2783 lkb_rsb_lookup);
ef0c2bb0 2784 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2785 r->res_first_lkid = lkb->lkb_id;
2786 _request_lock(r, lkb);
761b9d3f 2787 }
e7fd4179
DT		 2788 break;
2789
2790 default:
2791 log_error(r->res_ls, "confirm_master unknown error %d", error);
2792 }
2793}
2794
2795static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 2796 int namelen, unsigned long timeout_cs,
2797 void (*ast) (void *astparam),
2798 void *astparam,
2799 void (*bast) (void *astparam, int mode),
2800 struct dlm_args *args)
e7fd4179
DT		 2801{
2802 int rv = -EINVAL;
2803
2804 /* check for invalid arg usage */
2805
2806 if (mode < 0 || mode > DLM_LOCK_EX)
2807 goto out;
2808
2809 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2810 goto out;
2811
2812 if (flags & DLM_LKF_CANCEL)
2813 goto out;
2814
2815 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2816 goto out;
2817
2818 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2819 goto out;
2820
2821 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2822 goto out;
2823
2824 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2825 goto out;
2826
2827 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2828 goto out;
2829
2830 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2831 goto out;
2832
2833 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2834 goto out;
2835
2836 if (!ast || !lksb)
2837 goto out;
2838
2839 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2840 goto out;
2841
e7fd4179
DT		 2842 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2843 goto out;
2844
2845 /* these args will be copied to the lkb in validate_lock_args,
2846 it cannot be done now because when converting locks, fields in
2847 an active lkb cannot be modified before locking the rsb */
2848
2849 args->flags = flags;
e5dae548
DT		 2850 args->astfn = ast;
2851 args->astparam = astparam;
2852 args->bastfn = bast;
d7db923e 2853 args->timeout = timeout_cs;
e7fd4179
DT		 2854 args->mode = mode;
2855 args->lksb = lksb;
e7fd4179
DT		 2856 rv = 0;
2857 out:
2858 return rv;
2859}
2860
2861static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2862{
2863 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2864 DLM_LKF_FORCEUNLOCK))
2865 return -EINVAL;
2866
ef0c2bb0
DT		 2867 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2868 return -EINVAL;
2869
e7fd4179 2870 args->flags = flags;
e5dae548 2871 args->astparam = astarg;
e7fd4179
DT		 2872 return 0;
2873}
2874
2875static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2876 struct dlm_args *args)
2877{
2878 int rv = -EINVAL;
2879
2880 if (args->flags & DLM_LKF_CONVERT) {
2881 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2882 goto out;
2883
2884 if (args->flags & DLM_LKF_QUECVT &&
2885 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2886 goto out;
2887
2888 rv = -EBUSY;
2889 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2890 goto out;
2891
2892 if (lkb->lkb_wait_type)
2893 goto out;
ef0c2bb0
DT		 2894
2895 if (is_overlap(lkb))
2896 goto out;
e7fd4179
DT		 2897 }
2898
2899 lkb->lkb_exflags = args->flags;
2900 lkb->lkb_sbflags = 0;
e5dae548 2901 lkb->lkb_astfn = args->astfn;
e7fd4179 2902 lkb->lkb_astparam = args->astparam;
e5dae548 2903 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2904 lkb->lkb_rqmode = args->mode;
2905 lkb->lkb_lksb = args->lksb;
2906 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2907 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2908 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2909 rv = 0;
2910 out:
43279e53
DT		 2911 if (rv)
2912 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2913 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2914 lkb->lkb_status, lkb->lkb_wait_type,
2915 lkb->lkb_resource->res_name);
e7fd4179
DT		 2916 return rv;
2917}
2918
ef0c2bb0
DT		 2919/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2920 for success */
2921
2922/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2923 because there may be a lookup in progress and it's valid to do
2924 cancel/unlockf on it */
2925
e7fd4179
DT		 2926static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2927{
ef0c2bb0 2928 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2929 int rv = -EINVAL;
2930
ef0c2bb0
DT		 2931 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2932 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2933 dlm_print_lkb(lkb);
e7fd4179 2934 goto out;
ef0c2bb0 2935 }
e7fd4179 2936
ef0c2bb0
DT		 2937 /* an lkb may still exist even though the lock is EOL'ed due to a
2938 cancel, unlock or failed noqueue request; an app can't use these
2939 locks; return same error as if the lkid had not been found at all */
e7fd4179 2940
ef0c2bb0
DT		 2941 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2942 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2943 rv = -ENOENT;
e7fd4179 2944 goto out;
ef0c2bb0 2945 }
e7fd4179 2946
ef0c2bb0
DT		 2947 /* an lkb may be waiting for an rsb lookup to complete where the
2948 lookup was initiated by another lock */
2949
42dc1601
DT		 2950 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2951 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2952 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2953 list_del_init(&lkb->lkb_rsb_lookup);
2954 queue_cast(lkb->lkb_resource, lkb,
2955 args->flags & DLM_LKF_CANCEL ?
2956 -DLM_ECANCEL : -DLM_EUNLOCK);
2957 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2958 }
42dc1601
DT		 2959 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2960 rv = -EBUSY;
2961 goto out;
ef0c2bb0
DT		 2962 }
2963
2964 /* cancel not allowed with another cancel/unlock in progress */
2965
2966 if (args->flags & DLM_LKF_CANCEL) {
2967 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2968 goto out;
2969
2970 if (is_overlap(lkb))
2971 goto out;
2972
3ae1acf9
DT		 2973 /* don't let scand try to do a cancel */
2974 del_timeout(lkb);
2975
ef0c2bb0
DT		 2976 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2977 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2978 rv = -EBUSY;
2979 goto out;
2980 }
2981
a536e381
DT		 2982 /* there's nothing to cancel */
2983 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2984 !lkb->lkb_wait_type) {
2985 rv = -EBUSY;
2986 goto out;
2987 }
2988
ef0c2bb0
DT		 2989 switch (lkb->lkb_wait_type) {
2990 case DLM_MSG_LOOKUP:
2991 case DLM_MSG_REQUEST:
2992 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2993 rv = -EBUSY;
2994 goto out;
2995 case DLM_MSG_UNLOCK:
2996 case DLM_MSG_CANCEL:
2997 goto out;
2998 }
2999 /* add_to_waiters() will set OVERLAP_CANCEL */
3000 goto out_ok;
3001 }
3002
3003 /* do we need to allow a force-unlock if there's a normal unlock
3004 already in progress? in what conditions could the normal unlock
3005 fail such that we'd want to send a force-unlock to be sure? */
3006
3007 if (args->flags & DLM_LKF_FORCEUNLOCK) {
3008 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
3009 goto out;
3010
3011 if (is_overlap_unlock(lkb))
3012 goto out;
e7fd4179 3013
3ae1acf9
DT		 3014 /* don't let scand try to do a cancel */
3015 del_timeout(lkb);
3016
ef0c2bb0
DT		 3017 if (lkb->lkb_flags & DLM_IFL_RESEND) {
3018 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3019 rv = -EBUSY;
3020 goto out;
3021 }
3022
3023 switch (lkb->lkb_wait_type) {
3024 case DLM_MSG_LOOKUP:
3025 case DLM_MSG_REQUEST:
3026 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3027 rv = -EBUSY;
3028 goto out;
3029 case DLM_MSG_UNLOCK:
3030 goto out;
3031 }
3032 /* add_to_waiters() will set OVERLAP_UNLOCK */
3033 goto out_ok;
3034 }
3035
3036 /* normal unlock not allowed if there's any op in progress */
e7fd4179 3037 rv = -EBUSY;
ef0c2bb0 3038 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 3039 goto out;
3040
3041 out_ok:
ef0c2bb0
DT		 3042 /* an overlapping op shouldn't blow away exflags from other op */
3043 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 3044 lkb->lkb_sbflags = 0;
3045 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 3046 rv = 0;
3047 out:
ef0c2bb0
DT		 3048 if (rv)
3049 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
3050 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
3051 args->flags, lkb->lkb_wait_type,
3052 lkb->lkb_resource->res_name);
e7fd4179
DT		 3053 return rv;
3054}
3055
3056/*
3057 * Four stage 4 varieties:
3058 * do_request(), do_convert(), do_unlock(), do_cancel()
3059 * These are called on the master node for the given lock and
3060 * from the central locking logic.
3061 */
3062
3063static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3064{
3065 int error = 0;
3066
c503a621 3067 if (can_be_granted(r, lkb, 1, 0, NULL)) {
e7fd4179
DT		 3068 grant_lock(r, lkb);
3069 queue_cast(r, lkb, 0);
3070 goto out;
3071 }
3072
3073 if (can_be_queued(lkb)) {
3074 error = -EINPROGRESS;
3075 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9 3076 add_timeout(lkb);
e7fd4179
DT		 3077 goto out;
3078 }
3079
3080 error = -EAGAIN;
e7fd4179 3081 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3082 out:
3083 return error;
3084}
3085
cf6620ac
DT		 3086static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3087 int error)
3088{
3089 switch (error) {
3090 case -EAGAIN:
3091 if (force_blocking_asts(lkb))
3092 send_blocking_asts_all(r, lkb);
3093 break;
3094 case -EINPROGRESS:
3095 send_blocking_asts(r, lkb);
3096 break;
3097 }
3098}
3099
e7fd4179
DT		 3100static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3101{
3102 int error = 0;
c85d65e9 3103 int deadlk = 0;
e7fd4179
DT		 3104
3105 /* changing an existing lock may allow others to be granted */
3106
c503a621 3107 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
e7fd4179
DT		 3108 grant_lock(r, lkb);
3109 queue_cast(r, lkb, 0);
e7fd4179
DT		 3110 goto out;
3111 }
3112
c85d65e9
DT		 3113 /* can_be_granted() detected that this lock would block in a conversion
3114 deadlock, so we leave it on the granted queue and return EDEADLK in
3115 the ast for the convert. */
3116
3117 if (deadlk) {
3118 /* it's left on the granted queue */
c85d65e9
DT		 3119 revert_lock(r, lkb);
3120 queue_cast(r, lkb, -EDEADLK);
3121 error = -EDEADLK;
3122 goto out;
3123 }
3124
7d3c1feb
DT		 3125 /* is_demoted() means the can_be_granted() above set the grmode
3126 to NL, and left us on the granted queue. This auto-demotion
3127 (due to CONVDEADLK) might mean other locks, and/or this lock, are
3128 now grantable. We have to try to grant other converting locks
3129 before we try again to grant this one. */
3130
3131 if (is_demoted(lkb)) {
4875647a 3132 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
c503a621 3133 if (_can_be_granted(r, lkb, 1, 0)) {
7d3c1feb
DT		 3134 grant_lock(r, lkb);
3135 queue_cast(r, lkb, 0);
7d3c1feb
DT		 3136 goto out;
3137 }
3138 /* else fall through and move to convert queue */
3139 }
3140
3141 if (can_be_queued(lkb)) {
e7fd4179
DT		 3142 error = -EINPROGRESS;
3143 del_lkb(r, lkb);
3144 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3145 add_timeout(lkb);
e7fd4179
DT		 3146 goto out;
3147 }
3148
3149 error = -EAGAIN;
e7fd4179 3150 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3151 out:
3152 return error;
3153}
3154
cf6620ac
DT		 3155static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3156 int error)
3157{
3158 switch (error) {
3159 case 0:
4875647a 3160 grant_pending_locks(r, NULL);
cf6620ac
DT		 3161 /* grant_pending_locks also sends basts */
3162 break;
3163 case -EAGAIN:
3164 if (force_blocking_asts(lkb))
3165 send_blocking_asts_all(r, lkb);
3166 break;
3167 case -EINPROGRESS:
3168 send_blocking_asts(r, lkb);
3169 break;
3170 }
3171}
3172
e7fd4179
DT		 3173static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3174{
3175 remove_lock(r, lkb);
3176 queue_cast(r, lkb, -DLM_EUNLOCK);
e7fd4179
DT		 3177 return -DLM_EUNLOCK;
3178}
3179
cf6620ac
DT		 3180static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3181 int error)
3182{
4875647a 3183 grant_pending_locks(r, NULL);
cf6620ac
DT		 3184}
3185
ef0c2bb0 3186/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
c04fecb4 3187
e7fd4179
DT		 3188static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3189{
ef0c2bb0
DT		 3190 int error;
3191
3192 error = revert_lock(r, lkb);
3193 if (error) {
3194 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3195 return -DLM_ECANCEL;
3196 }
3197 return 0;
e7fd4179
DT		 3198}
3199
cf6620ac
DT		 3200static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3201 int error)
3202{
3203 if (error)
4875647a 3204 grant_pending_locks(r, NULL);
cf6620ac
DT		 3205}
3206
e7fd4179
DT		 3207/*
3208 * Four stage 3 varieties:
3209 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3210 */
3211
3212/* add a new lkb to a possibly new rsb, called by requesting process */
3213
3214static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3215{
3216 int error;
3217
3218 /* set_master: sets lkb nodeid from r */
3219
3220 error = set_master(r, lkb);
3221 if (error < 0)
3222 goto out;
3223 if (error) {
3224 error = 0;
3225 goto out;
3226 }
3227
cf6620ac 3228 if (is_remote(r)) {
e7fd4179
DT		 3229 /* receive_request() calls do_request() on remote node */
3230 error = send_request(r, lkb);
cf6620ac 3231 } else {
e7fd4179 3232 error = do_request(r, lkb);
cf6620ac
DT		 3233 /* for remote locks the request_reply is sent
3234 between do_request and do_request_effects */
3235 do_request_effects(r, lkb, error);
3236 }
e7fd4179
DT		 3237 out:
3238 return error;
3239}
3240
3bcd3687 3241/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 3242
3243static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3244{
3245 int error;
3246
cf6620ac 3247 if (is_remote(r)) {
e7fd4179
DT		 3248 /* receive_convert() calls do_convert() on remote node */
3249 error = send_convert(r, lkb);
cf6620ac 3250 } else {
e7fd4179 3251 error = do_convert(r, lkb);
cf6620ac
DT		 3252 /* for remote locks the convert_reply is sent
3253 between do_convert and do_convert_effects */
3254 do_convert_effects(r, lkb, error);
3255 }
e7fd4179
DT		 3256
3257 return error;
3258}
3259
3260/* remove an existing lkb from the granted queue */
3261
3262static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3263{
3264 int error;
3265
cf6620ac 3266 if (is_remote(r)) {
e7fd4179
DT		 3267 /* receive_unlock() calls do_unlock() on remote node */
3268 error = send_unlock(r, lkb);
cf6620ac 3269 } else {
e7fd4179 3270 error = do_unlock(r, lkb);
cf6620ac
DT		 3271 /* for remote locks the unlock_reply is sent
3272 between do_unlock and do_unlock_effects */
3273 do_unlock_effects(r, lkb, error);
3274 }
e7fd4179
DT		 3275
3276 return error;
3277}
3278
3279/* remove an existing lkb from the convert or wait queue */
3280
3281static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3282{
3283 int error;
3284
cf6620ac 3285 if (is_remote(r)) {
e7fd4179
DT		 3286 /* receive_cancel() calls do_cancel() on remote node */
3287 error = send_cancel(r, lkb);
cf6620ac 3288 } else {
e7fd4179 3289 error = do_cancel(r, lkb);
cf6620ac
DT		 3290 /* for remote locks the cancel_reply is sent
3291 between do_cancel and do_cancel_effects */
3292 do_cancel_effects(r, lkb, error);
3293 }
e7fd4179
DT		 3294
3295 return error;
3296}
3297
3298/*
3299 * Four stage 2 varieties:
3300 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3301 */
3302
3303static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
3304 int len, struct dlm_args *args)
3305{
3306 struct dlm_rsb *r;
3307 int error;
3308
3309 error = validate_lock_args(ls, lkb, args);
3310 if (error)
c04fecb4 3311 return error;
e7fd4179 3312
c04fecb4 3313 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
e7fd4179 3314 if (error)
c04fecb4 3315 return error;
e7fd4179
DT		 3316
3317 lock_rsb(r);
3318
3319 attach_lkb(r, lkb);
3320 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3321
3322 error = _request_lock(r, lkb);
3323
3324 unlock_rsb(r);
3325 put_rsb(r);
e7fd4179
DT		 3326 return error;
3327}
3328
3329static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3330 struct dlm_args *args)
3331{
3332 struct dlm_rsb *r;
3333 int error;
3334
3335 r = lkb->lkb_resource;
3336
3337 hold_rsb(r);
3338 lock_rsb(r);
3339
3340 error = validate_lock_args(ls, lkb, args);
3341 if (error)
3342 goto out;
3343
3344 error = _convert_lock(r, lkb);
3345 out:
3346 unlock_rsb(r);
3347 put_rsb(r);
3348 return error;
3349}
3350
3351static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3352 struct dlm_args *args)
3353{
3354 struct dlm_rsb *r;
3355 int error;
3356
3357 r = lkb->lkb_resource;
3358
3359 hold_rsb(r);
3360 lock_rsb(r);
3361
3362 error = validate_unlock_args(lkb, args);
3363 if (error)
3364 goto out;
3365
3366 error = _unlock_lock(r, lkb);
3367 out:
3368 unlock_rsb(r);
3369 put_rsb(r);
3370 return error;
3371}
3372
3373static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3374 struct dlm_args *args)
3375{
3376 struct dlm_rsb *r;
3377 int error;
3378
3379 r = lkb->lkb_resource;
3380
3381 hold_rsb(r);
3382 lock_rsb(r);
3383
3384 error = validate_unlock_args(lkb, args);
3385 if (error)
3386 goto out;
3387
3388 error = _cancel_lock(r, lkb);
3389 out:
3390 unlock_rsb(r);
3391 put_rsb(r);
3392 return error;
3393}
3394
3395/*
3396 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3397 */
3398
3399int dlm_lock(dlm_lockspace_t *lockspace,
3400 int mode,
3401 struct dlm_lksb *lksb,
3402 uint32_t flags,
3403 void *name,
3404 unsigned int namelen,
3405 uint32_t parent_lkid,
3406 void (*ast) (void *astarg),
3407 void *astarg,
3bcd3687 3408 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 3409{
3410 struct dlm_ls *ls;
3411 struct dlm_lkb *lkb;
3412 struct dlm_args args;
3413 int error, convert = flags & DLM_LKF_CONVERT;
3414
3415 ls = dlm_find_lockspace_local(lockspace);
3416 if (!ls)
3417 return -EINVAL;
3418
85e86edf 3419 dlm_lock_recovery(ls);
e7fd4179
DT		 3420
3421 if (convert)
3422 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3423 else
3424 error = create_lkb(ls, &lkb);
3425
3426 if (error)
3427 goto out;
3428
d7db923e 3429 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 3430 astarg, bast, &args);
e7fd4179
DT		 3431 if (error)
3432 goto out_put;
3433
3434 if (convert)
3435 error = convert_lock(ls, lkb, &args);
3436 else
3437 error = request_lock(ls, lkb, name, namelen, &args);
3438
3439 if (error == -EINPROGRESS)
3440 error = 0;
3441 out_put:
3442 if (convert || error)
b3f58d8f 3443 __put_lkb(ls, lkb);
c85d65e9 3444 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 3445 error = 0;
3446 out:
85e86edf 3447 dlm_unlock_recovery(ls);
e7fd4179
DT		 3448 dlm_put_lockspace(ls);
3449 return error;
3450}
3451
3452int dlm_unlock(dlm_lockspace_t *lockspace,
3453 uint32_t lkid,
3454 uint32_t flags,
3455 struct dlm_lksb *lksb,
3456 void *astarg)
3457{
3458 struct dlm_ls *ls;
3459 struct dlm_lkb *lkb;
3460 struct dlm_args args;
3461 int error;
3462
3463 ls = dlm_find_lockspace_local(lockspace);
3464 if (!ls)
3465 return -EINVAL;
3466
85e86edf 3467 dlm_lock_recovery(ls);
e7fd4179
DT		 3468
3469 error = find_lkb(ls, lkid, &lkb);
3470 if (error)
3471 goto out;
3472
3473 error = set_unlock_args(flags, astarg, &args);
3474 if (error)
3475 goto out_put;
3476
3477 if (flags & DLM_LKF_CANCEL)
3478 error = cancel_lock(ls, lkb, &args);
3479 else
3480 error = unlock_lock(ls, lkb, &args);
3481
3482 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3483 error = 0;
ef0c2bb0
DT		 3484 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3485 error = 0;
e7fd4179 3486 out_put:
b3f58d8f 3487 dlm_put_lkb(lkb);
e7fd4179 3488 out:
85e86edf 3489 dlm_unlock_recovery(ls);
e7fd4179
DT		 3490 dlm_put_lockspace(ls);
3491 return error;
3492}
3493
3494/*
3495 * send/receive routines for remote operations and replies
3496 *
3497 * send_args
3498 * send_common
3499 * send_request receive_request
3500 * send_convert receive_convert
3501 * send_unlock receive_unlock
3502 * send_cancel receive_cancel
3503 * send_grant receive_grant
3504 * send_bast receive_bast
3505 * send_lookup receive_lookup
3506 * send_remove receive_remove
3507 *
3508 * send_common_reply
3509 * receive_request_reply send_request_reply
3510 * receive_convert_reply send_convert_reply
3511 * receive_unlock_reply send_unlock_reply
3512 * receive_cancel_reply send_cancel_reply
3513 * receive_lookup_reply send_lookup_reply
3514 */
3515
7e4dac33
DT		 3516static int _create_message(struct dlm_ls *ls, int mb_len,
3517 int to_nodeid, int mstype,
3518 struct dlm_message **ms_ret,
3519 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 3520{
3521 struct dlm_message *ms;
3522 struct dlm_mhandle *mh;
3523 char *mb;
e7fd4179
DT		 3524
3525 /* get_buffer gives us a message handle (mh) that we need to
3526 pass into lowcomms_commit and a message buffer (mb) that we
3527 write our data into */
3528
573c24c4 3529 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
e7fd4179
DT		 3530 if (!mh)
3531 return -ENOBUFS;
3532
3533 memset(mb, 0, mb_len);
3534
3535 ms = (struct dlm_message *) mb;
3536
3537 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 3538 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 3539 ms->m_header.h_nodeid = dlm_our_nodeid();
3540 ms->m_header.h_length = mb_len;
3541 ms->m_header.h_cmd = DLM_MSG;
3542
3543 ms->m_type = mstype;
3544
3545 *mh_ret = mh;
3546 *ms_ret = ms;
3547 return 0;
3548}
3549
7e4dac33
DT		 3550static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3551 int to_nodeid, int mstype,
3552 struct dlm_message **ms_ret,
3553 struct dlm_mhandle **mh_ret)
3554{
3555 int mb_len = sizeof(struct dlm_message);
3556
3557 switch (mstype) {
3558 case DLM_MSG_REQUEST:
3559 case DLM_MSG_LOOKUP:
3560 case DLM_MSG_REMOVE:
3561 mb_len += r->res_length;
3562 break;
3563 case DLM_MSG_CONVERT:
3564 case DLM_MSG_UNLOCK:
3565 case DLM_MSG_REQUEST_REPLY:
3566 case DLM_MSG_CONVERT_REPLY:
3567 case DLM_MSG_GRANT:
3568 if (lkb && lkb->lkb_lvbptr)
3569 mb_len += r->res_ls->ls_lvblen;
3570 break;
3571 }
3572
3573 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3574 ms_ret, mh_ret);
3575}
3576
e7fd4179
DT		 3577/* further lowcomms enhancements or alternate implementations may make
3578 the return value from this function useful at some point */
3579
3580static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
3581{
3582 dlm_message_out(ms);
3583 dlm_lowcomms_commit_buffer(mh);
3584 return 0;
3585}
3586
3587static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3588 struct dlm_message *ms)
3589{
3590 ms->m_nodeid = lkb->lkb_nodeid;
3591 ms->m_pid = lkb->lkb_ownpid;
3592 ms->m_lkid = lkb->lkb_id;
3593 ms->m_remid = lkb->lkb_remid;
3594 ms->m_exflags = lkb->lkb_exflags;
3595 ms->m_sbflags = lkb->lkb_sbflags;
3596 ms->m_flags = lkb->lkb_flags;
3597 ms->m_lvbseq = lkb->lkb_lvbseq;
3598 ms->m_status = lkb->lkb_status;
3599 ms->m_grmode = lkb->lkb_grmode;
3600 ms->m_rqmode = lkb->lkb_rqmode;
3601 ms->m_hash = r->res_hash;
3602
3603 /* m_result and m_bastmode are set from function args,
3604 not from lkb fields */
3605
e5dae548 3606 if (lkb->lkb_bastfn)
8304d6f2 3607 ms->m_asts |= DLM_CB_BAST;
e5dae548 3608 if (lkb->lkb_astfn)
8304d6f2 3609 ms->m_asts |= DLM_CB_CAST;
e7fd4179 3610
da49f36f
DT		 3611 /* compare with switch in create_message; send_remove() doesn't
3612 use send_args() */
e7fd4179 3613
da49f36f
DT		 3614 switch (ms->m_type) {
3615 case DLM_MSG_REQUEST:
3616 case DLM_MSG_LOOKUP:
3617 memcpy(ms->m_extra, r->res_name, r->res_length);
3618 break;
3619 case DLM_MSG_CONVERT:
3620 case DLM_MSG_UNLOCK:
3621 case DLM_MSG_REQUEST_REPLY:
3622 case DLM_MSG_CONVERT_REPLY:
3623 case DLM_MSG_GRANT:
3624 if (!lkb->lkb_lvbptr)
3625 break;
e7fd4179 3626 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 3627 break;
3628 }
e7fd4179
DT		 3629}
3630
3631static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3632{
3633 struct dlm_message *ms;
3634 struct dlm_mhandle *mh;
3635 int to_nodeid, error;
3636
c6ff669b
DT		 3637 to_nodeid = r->res_nodeid;
3638
3639 error = add_to_waiters(lkb, mstype, to_nodeid);
ef0c2bb0
DT		 3640 if (error)
3641 return error;
e7fd4179 3642
e7fd4179
DT		 3643 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3644 if (error)
3645 goto fail;
3646
3647 send_args(r, lkb, ms);
3648
3649 error = send_message(mh, ms);
3650 if (error)
3651 goto fail;
3652 return 0;
3653
3654 fail:
ef0c2bb0 3655 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 3656 return error;
3657}
3658
3659static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3660{
3661 return send_common(r, lkb, DLM_MSG_REQUEST);
3662}
3663
3664static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3665{
3666 int error;
3667
3668 error = send_common(r, lkb, DLM_MSG_CONVERT);
3669
3670 /* down conversions go without a reply from the master */
3671 if (!error && down_conversion(lkb)) {
ef0c2bb0 3672 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2a7ce0ed 3673 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
ef0c2bb0 3674 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179
DT		 3675 r->res_ls->ls_stub_ms.m_result = 0;
3676 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3677 }
3678
3679 return error;
3680}
3681
3682/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3683 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3684 that the master is still correct. */
3685
3686static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3687{
3688 return send_common(r, lkb, DLM_MSG_UNLOCK);
3689}
3690
3691static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3692{
3693 return send_common(r, lkb, DLM_MSG_CANCEL);
3694}
3695
3696static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3697{
3698 struct dlm_message *ms;
3699 struct dlm_mhandle *mh;
3700 int to_nodeid, error;
3701
3702 to_nodeid = lkb->lkb_nodeid;
3703
3704 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3705 if (error)
3706 goto out;
3707
3708 send_args(r, lkb, ms);
3709
3710 ms->m_result = 0;
3711
3712 error = send_message(mh, ms);
3713 out:
3714 return error;
3715}
3716
3717static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3718{
3719 struct dlm_message *ms;
3720 struct dlm_mhandle *mh;
3721 int to_nodeid, error;
3722
3723 to_nodeid = lkb->lkb_nodeid;
3724
3725 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3726 if (error)
3727 goto out;
3728
3729 send_args(r, lkb, ms);
3730
3731 ms->m_bastmode = mode;
3732
3733 error = send_message(mh, ms);
3734 out:
3735 return error;
3736}
3737
3738static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3739{
3740 struct dlm_message *ms;
3741 struct dlm_mhandle *mh;
3742 int to_nodeid, error;
3743
c6ff669b
DT		 3744 to_nodeid = dlm_dir_nodeid(r);
3745
3746 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
ef0c2bb0
DT		 3747 if (error)
3748 return error;
e7fd4179 3749
e7fd4179
DT		 3750 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3751 if (error)
3752 goto fail;
3753
3754 send_args(r, lkb, ms);
3755
3756 error = send_message(mh, ms);
3757 if (error)
3758 goto fail;
3759 return 0;
3760
3761 fail:
ef0c2bb0 3762 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 3763 return error;
3764}
3765
3766static int send_remove(struct dlm_rsb *r)
3767{
3768 struct dlm_message *ms;
3769 struct dlm_mhandle *mh;
3770 int to_nodeid, error;
3771
3772 to_nodeid = dlm_dir_nodeid(r);
3773
3774 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3775 if (error)
3776 goto out;
3777
3778 memcpy(ms->m_extra, r->res_name, r->res_length);
3779 ms->m_hash = r->res_hash;
3780
3781 error = send_message(mh, ms);
3782 out:
3783 return error;
3784}
3785
3786static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3787 int mstype, int rv)
3788{
3789 struct dlm_message *ms;
3790 struct dlm_mhandle *mh;
3791 int to_nodeid, error;
3792
3793 to_nodeid = lkb->lkb_nodeid;
3794
3795 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3796 if (error)
3797 goto out;
3798
3799 send_args(r, lkb, ms);
3800
3801 ms->m_result = rv;
3802
3803 error = send_message(mh, ms);
3804 out:
3805 return error;
3806}
3807
3808static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3809{
3810 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3811}
3812
3813static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3814{
3815 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3816}
3817
3818static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3819{
3820 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3821}
3822
3823static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3824{
3825 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3826}
3827
3828static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3829 int ret_nodeid, int rv)
3830{
3831 struct dlm_rsb *r = &ls->ls_stub_rsb;
3832 struct dlm_message *ms;
3833 struct dlm_mhandle *mh;
3834 int error, nodeid = ms_in->m_header.h_nodeid;
3835
3836 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3837 if (error)
3838 goto out;
3839
3840 ms->m_lkid = ms_in->m_lkid;
3841 ms->m_result = rv;
3842 ms->m_nodeid = ret_nodeid;
3843
3844 error = send_message(mh, ms);
3845 out:
3846 return error;
3847}
3848
3849/* which args we save from a received message depends heavily on the type
3850 of message, unlike the send side where we can safely send everything about
3851 the lkb for any type of message */
3852
3853static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3854{
3855 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 3856 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 3857 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3858 (ms->m_flags & 0x0000FFFF);
3859}
3860
3861static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3862{
2a7ce0ed
DT		 3863 if (ms->m_flags == DLM_IFL_STUB_MS)
3864 return;
3865
e7fd4179
DT		 3866 lkb->lkb_sbflags = ms->m_sbflags;
3867 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3868 (ms->m_flags & 0x0000FFFF);
3869}
3870
3871static int receive_extralen(struct dlm_message *ms)
3872{
3873 return (ms->m_header.h_length - sizeof(struct dlm_message));
3874}
3875
e7fd4179
DT		 3876static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3877 struct dlm_message *ms)
3878{
3879 int len;
3880
3881 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3882 if (!lkb->lkb_lvbptr)
52bda2b5 3883 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 3884 if (!lkb->lkb_lvbptr)
3885 return -ENOMEM;
3886 len = receive_extralen(ms);
a9cc9159
AV		 3887 if (len > DLM_RESNAME_MAXLEN)
3888 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 3889 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3890 }
3891 return 0;
3892}
3893
e5dae548
DT		 3894static void fake_bastfn(void *astparam, int mode)
3895{
3896 log_print("fake_bastfn should not be called");
3897}
3898
3899static void fake_astfn(void *astparam)
3900{
3901 log_print("fake_astfn should not be called");
3902}
3903
e7fd4179
DT		 3904static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3905 struct dlm_message *ms)
3906{
3907 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3908 lkb->lkb_ownpid = ms->m_pid;
3909 lkb->lkb_remid = ms->m_lkid;
3910 lkb->lkb_grmode = DLM_LOCK_IV;
3911 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548 3912
8304d6f2
DT		 3913 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3914 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 3915
8d07fd50
DT		 3916 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3917 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3918 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3919 if (!lkb->lkb_lvbptr)
3920 return -ENOMEM;
3921 }
e7fd4179
DT		 3922
3923 return 0;
3924}
3925
3926static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3927 struct dlm_message *ms)
3928{
e7fd4179
DT		 3929 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3930 return -EBUSY;
3931
e7fd4179
DT		 3932 if (receive_lvb(ls, lkb, ms))
3933 return -ENOMEM;
3934
3935 lkb->lkb_rqmode = ms->m_rqmode;
3936 lkb->lkb_lvbseq = ms->m_lvbseq;
3937
3938 return 0;
3939}
3940
3941static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3942 struct dlm_message *ms)
3943{
e7fd4179
DT		 3944 if (receive_lvb(ls, lkb, ms))
3945 return -ENOMEM;
3946 return 0;
3947}
3948
3949/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3950 uses to send a reply and that the remote end uses to process the reply. */
3951
3952static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3953{
3954 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3955 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3956 lkb->lkb_remid = ms->m_lkid;
3957}
3958
c54e04b0
DT		 3959/* This is called after the rsb is locked so that we can safely inspect
3960 fields in the lkb. */
3961
3962static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3963{
3964 int from = ms->m_header.h_nodeid;
3965 int error = 0;
3966
3967 switch (ms->m_type) {
3968 case DLM_MSG_CONVERT:
3969 case DLM_MSG_UNLOCK:
3970 case DLM_MSG_CANCEL:
3971 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3972 error = -EINVAL;
3973 break;
3974
3975 case DLM_MSG_CONVERT_REPLY:
3976 case DLM_MSG_UNLOCK_REPLY:
3977 case DLM_MSG_CANCEL_REPLY:
3978 case DLM_MSG_GRANT:
3979 case DLM_MSG_BAST:
3980 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3981 error = -EINVAL;
3982 break;
3983
3984 case DLM_MSG_REQUEST_REPLY:
3985 if (!is_process_copy(lkb))
3986 error = -EINVAL;
3987 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3988 error = -EINVAL;
3989 break;
3990
3991 default:
3992 error = -EINVAL;
3993 }
3994
3995 if (error)
3996 log_error(lkb->lkb_resource->res_ls,
3997 "ignore invalid message %d from %d %x %x %x %d",
3998 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
3999 lkb->lkb_flags, lkb->lkb_nodeid);
4000 return error;
4001}
4002
96006ea6
DT		 4003static void send_repeat_remove(struct dlm_ls *ls, char *ms_name, int len)
4004{
4005 char name[DLM_RESNAME_MAXLEN + 1];
4006 struct dlm_message *ms;
4007 struct dlm_mhandle *mh;
4008 struct dlm_rsb *r;
4009 uint32_t hash, b;
4010 int rv, dir_nodeid;
4011
4012 memset(name, 0, sizeof(name));
4013 memcpy(name, ms_name, len);
4014
4015 hash = jhash(name, len, 0);
4016 b = hash & (ls->ls_rsbtbl_size - 1);
4017
4018 dir_nodeid = dlm_hash2nodeid(ls, hash);
4019
4020 log_error(ls, "send_repeat_remove dir %d %s", dir_nodeid, name);
4021
4022 spin_lock(&ls->ls_rsbtbl[b].lock);
4023 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4024 if (!rv) {
4025 spin_unlock(&ls->ls_rsbtbl[b].lock);
4026 log_error(ls, "repeat_remove on keep %s", name);
4027 return;
4028 }
4029
4030 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4031 if (!rv) {
4032 spin_unlock(&ls->ls_rsbtbl[b].lock);
4033 log_error(ls, "repeat_remove on toss %s", name);
4034 return;
4035 }
4036
4037 /* use ls->remove_name2 to avoid conflict with shrink? */
4038
4039 spin_lock(&ls->ls_remove_spin);
4040 ls->ls_remove_len = len;
4041 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
4042 spin_unlock(&ls->ls_remove_spin);
4043 spin_unlock(&ls->ls_rsbtbl[b].lock);
4044
4045 rv = _create_message(ls, sizeof(struct dlm_message) + len,
4046 dir_nodeid, DLM_MSG_REMOVE, &ms, &mh);
4047 if (rv)
4048 return;
4049
4050 memcpy(ms->m_extra, name, len);
4051 ms->m_hash = hash;
4052
4053 send_message(mh, ms);
4054
4055 spin_lock(&ls->ls_remove_spin);
4056 ls->ls_remove_len = 0;
4057 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
4058 spin_unlock(&ls->ls_remove_spin);
4059}
4060
6d40c4a7 4061static int receive_request(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4062{
4063 struct dlm_lkb *lkb;
4064 struct dlm_rsb *r;
c04fecb4 4065 int from_nodeid;
96006ea6 4066 int error, namelen = 0;
e7fd4179 4067
c04fecb4
DT		 4068 from_nodeid = ms->m_header.h_nodeid;
4069
e7fd4179
DT		 4070 error = create_lkb(ls, &lkb);
4071 if (error)
4072 goto fail;
4073
4074 receive_flags(lkb, ms);
4075 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4076 error = receive_request_args(ls, lkb, ms);
4077 if (error) {
b3f58d8f 4078 __put_lkb(ls, lkb);
e7fd4179
DT		 4079 goto fail;
4080 }
4081
c04fecb4
DT		 4082 /* The dir node is the authority on whether we are the master
4083 for this rsb or not, so if the master sends us a request, we should
4084 recreate the rsb if we've destroyed it. This race happens when we
4085 send a remove message to the dir node at the same time that the dir
4086 node sends us a request for the rsb. */
4087
e7fd4179
DT		 4088 namelen = receive_extralen(ms);
4089
c04fecb4
DT		 4090 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
4091 R_RECEIVE_REQUEST, &r);
e7fd4179 4092 if (error) {
b3f58d8f 4093 __put_lkb(ls, lkb);
e7fd4179
DT		 4094 goto fail;
4095 }
4096
4097 lock_rsb(r);
4098
c04fecb4
DT		 4099 if (r->res_master_nodeid != dlm_our_nodeid()) {
4100 error = validate_master_nodeid(ls, r, from_nodeid);
4101 if (error) {
4102 unlock_rsb(r);
4103 put_rsb(r);
4104 __put_lkb(ls, lkb);
4105 goto fail;
4106 }
4107 }
4108
e7fd4179
DT		 4109 attach_lkb(r, lkb);
4110 error = do_request(r, lkb);
4111 send_request_reply(r, lkb, error);
cf6620ac 4112 do_request_effects(r, lkb, error);
e7fd4179
DT		 4113
4114 unlock_rsb(r);
4115 put_rsb(r);
4116
4117 if (error == -EINPROGRESS)
4118 error = 0;
4119 if (error)
b3f58d8f 4120 dlm_put_lkb(lkb);
6d40c4a7 4121 return 0;
e7fd4179
DT		 4122
4123 fail:
c04fecb4
DT		 4124 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
4125 and do this receive_request again from process_lookup_list once
4126 we get the lookup reply. This would avoid a many repeated
4127 ENOTBLK request failures when the lookup reply designating us
4128 as master is delayed. */
4129
4130 /* We could repeatedly return -EBADR here if our send_remove() is
4131 delayed in being sent/arriving/being processed on the dir node.
4132 Another node would repeatedly lookup up the master, and the dir
4133 node would continue returning our nodeid until our send_remove
96006ea6
DT		 4134 took effect.
4135
4136 We send another remove message in case our previous send_remove
4137 was lost/ignored/missed somehow. */
c04fecb4
DT		 4138
4139 if (error != -ENOTBLK) {
4140 log_limit(ls, "receive_request %x from %d %d",
4141 ms->m_lkid, from_nodeid, error);
4142 }
4143
96006ea6
DT		 4144 if (namelen && error == -EBADR) {
4145 send_repeat_remove(ls, ms->m_extra, namelen);
4146 msleep(1000);
4147 }
4148
e7fd4179
DT		 4149 setup_stub_lkb(ls, ms);
4150 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4151 return error;
e7fd4179
DT		 4152}
4153
6d40c4a7 4154static int receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4155{
4156 struct dlm_lkb *lkb;
4157 struct dlm_rsb *r;
90135925 4158 int error, reply = 1;
e7fd4179
DT		 4159
4160 error = find_lkb(ls, ms->m_remid, &lkb);
4161 if (error)
4162 goto fail;
4163
6d40c4a7 4164 if (lkb->lkb_remid != ms->m_lkid) {
4875647a
DT		 4165 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
4166 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
4167 (unsigned long long)lkb->lkb_recover_seq,
6d40c4a7
DT		 4168 ms->m_header.h_nodeid, ms->m_lkid);
4169 error = -ENOENT;
4170 goto fail;
4171 }
4172
e7fd4179
DT		 4173 r = lkb->lkb_resource;
4174
4175 hold_rsb(r);
4176 lock_rsb(r);
4177
c54e04b0
DT		 4178 error = validate_message(lkb, ms);
4179 if (error)
4180 goto out;
4181
e7fd4179 4182 receive_flags(lkb, ms);
cf6620ac 4183
e7fd4179 4184 error = receive_convert_args(ls, lkb, ms);
cf6620ac
DT		 4185 if (error) {
4186 send_convert_reply(r, lkb, error);
4187 goto out;
4188 }
4189
e7fd4179
DT		 4190 reply = !down_conversion(lkb);
4191
4192 error = do_convert(r, lkb);
e7fd4179
DT		 4193 if (reply)
4194 send_convert_reply(r, lkb, error);
cf6620ac 4195 do_convert_effects(r, lkb, error);
c54e04b0 4196 out:
e7fd4179
DT		 4197 unlock_rsb(r);
4198 put_rsb(r);
b3f58d8f 4199 dlm_put_lkb(lkb);
6d40c4a7 4200 return 0;
e7fd4179
DT		 4201
4202 fail:
4203 setup_stub_lkb(ls, ms);
4204 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4205 return error;
e7fd4179
DT		 4206}
4207
6d40c4a7 4208static int receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4209{
4210 struct dlm_lkb *lkb;
4211 struct dlm_rsb *r;
4212 int error;
4213
4214 error = find_lkb(ls, ms->m_remid, &lkb);
4215 if (error)
4216 goto fail;
4217
6d40c4a7
DT		 4218 if (lkb->lkb_remid != ms->m_lkid) {
4219 log_error(ls, "receive_unlock %x remid %x remote %d %x",
4220 lkb->lkb_id, lkb->lkb_remid,
4221 ms->m_header.h_nodeid, ms->m_lkid);
4222 error = -ENOENT;
4223 goto fail;
4224 }
4225
e7fd4179
DT		 4226 r = lkb->lkb_resource;
4227
4228 hold_rsb(r);
4229 lock_rsb(r);
4230
c54e04b0
DT		 4231 error = validate_message(lkb, ms);
4232 if (error)
4233 goto out;
4234
e7fd4179 4235 receive_flags(lkb, ms);
cf6620ac 4236
e7fd4179 4237 error = receive_unlock_args(ls, lkb, ms);
cf6620ac
DT		 4238 if (error) {
4239 send_unlock_reply(r, lkb, error);
4240 goto out;
4241 }
e7fd4179
DT		 4242
4243 error = do_unlock(r, lkb);
e7fd4179 4244 send_unlock_reply(r, lkb, error);
cf6620ac 4245 do_unlock_effects(r, lkb, error);
c54e04b0 4246 out:
e7fd4179
DT		 4247 unlock_rsb(r);
4248 put_rsb(r);
b3f58d8f 4249 dlm_put_lkb(lkb);
6d40c4a7 4250 return 0;
e7fd4179
DT		 4251
4252 fail:
4253 setup_stub_lkb(ls, ms);
4254 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4255 return error;
e7fd4179
DT		 4256}
4257
6d40c4a7 4258static int receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4259{
4260 struct dlm_lkb *lkb;
4261 struct dlm_rsb *r;
4262 int error;
4263
4264 error = find_lkb(ls, ms->m_remid, &lkb);
4265 if (error)
4266 goto fail;
4267
4268 receive_flags(lkb, ms);
4269
4270 r = lkb->lkb_resource;
4271
4272 hold_rsb(r);
4273 lock_rsb(r);
4274
c54e04b0
DT		 4275 error = validate_message(lkb, ms);
4276 if (error)
4277 goto out;
4278
e7fd4179
DT		 4279 error = do_cancel(r, lkb);
4280 send_cancel_reply(r, lkb, error);
cf6620ac 4281 do_cancel_effects(r, lkb, error);
c54e04b0 4282 out:
e7fd4179
DT		 4283 unlock_rsb(r);
4284 put_rsb(r);
b3f58d8f 4285 dlm_put_lkb(lkb);
6d40c4a7 4286 return 0;
e7fd4179
DT		 4287
4288 fail:
4289 setup_stub_lkb(ls, ms);
4290 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4291 return error;
e7fd4179
DT		 4292}
4293
6d40c4a7 4294static int receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4295{
4296 struct dlm_lkb *lkb;
4297 struct dlm_rsb *r;
4298 int error;
4299
4300 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4301 if (error)
4302 return error;
e7fd4179
DT		 4303
4304 r = lkb->lkb_resource;
4305
4306 hold_rsb(r);
4307 lock_rsb(r);
4308
c54e04b0
DT		 4309 error = validate_message(lkb, ms);
4310 if (error)
4311 goto out;
4312
e7fd4179 4313 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 4314 if (is_altmode(lkb))
4315 munge_altmode(lkb, ms);
e7fd4179
DT		 4316 grant_lock_pc(r, lkb, ms);
4317 queue_cast(r, lkb, 0);
c54e04b0 4318 out:
e7fd4179
DT		 4319 unlock_rsb(r);
4320 put_rsb(r);
b3f58d8f 4321 dlm_put_lkb(lkb);
6d40c4a7 4322 return 0;
e7fd4179
DT		 4323}
4324
6d40c4a7 4325static int receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4326{
4327 struct dlm_lkb *lkb;
4328 struct dlm_rsb *r;
4329 int error;
4330
4331 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4332 if (error)
4333 return error;
e7fd4179
DT		 4334
4335 r = lkb->lkb_resource;
4336
4337 hold_rsb(r);
4338 lock_rsb(r);
4339
c54e04b0
DT		 4340 error = validate_message(lkb, ms);
4341 if (error)
4342 goto out;
e7fd4179 4343
c54e04b0 4344 queue_bast(r, lkb, ms->m_bastmode);
4875647a 4345 lkb->lkb_highbast = ms->m_bastmode;
c54e04b0 4346 out:
e7fd4179
DT		 4347 unlock_rsb(r);
4348 put_rsb(r);
b3f58d8f 4349 dlm_put_lkb(lkb);
6d40c4a7 4350 return 0;
e7fd4179
DT		 4351}
4352
4353static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
4354{
c04fecb4 4355 int len, error, ret_nodeid, from_nodeid, our_nodeid;
e7fd4179
DT		 4356
4357 from_nodeid = ms->m_header.h_nodeid;
4358 our_nodeid = dlm_our_nodeid();
4359
4360 len = receive_extralen(ms);
4361
c04fecb4
DT		 4362 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4363 &ret_nodeid, NULL);
e7fd4179
DT		 4364
4365 /* Optimization: we're master so treat lookup as a request */
4366 if (!error && ret_nodeid == our_nodeid) {
4367 receive_request(ls, ms);
4368 return;
4369 }
e7fd4179
DT		 4370 send_lookup_reply(ls, ms, ret_nodeid, error);
4371}
4372
4373static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
4374{
c04fecb4
DT		 4375 char name[DLM_RESNAME_MAXLEN+1];
4376 struct dlm_rsb *r;
4377 uint32_t hash, b;
4378 int rv, len, dir_nodeid, from_nodeid;
e7fd4179
DT		 4379
4380 from_nodeid = ms->m_header.h_nodeid;
4381
4382 len = receive_extralen(ms);
4383
c04fecb4
DT		 4384 if (len > DLM_RESNAME_MAXLEN) {
4385 log_error(ls, "receive_remove from %d bad len %d",
4386 from_nodeid, len);
4387 return;
4388 }
4389
e7fd4179
DT		 4390 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
4391 if (dir_nodeid != dlm_our_nodeid()) {
c04fecb4
DT		 4392 log_error(ls, "receive_remove from %d bad nodeid %d",
4393 from_nodeid, dir_nodeid);
e7fd4179
DT		 4394 return;
4395 }
4396
c04fecb4
DT		 4397 /* Look for name on rsbtbl.toss, if it's there, kill it.
4398 If it's on rsbtbl.keep, it's being used, and we should ignore this
4399 message. This is an expected race between the dir node sending a
4400 request to the master node at the same time as the master node sends
4401 a remove to the dir node. The resolution to that race is for the
4402 dir node to ignore the remove message, and the master node to
4403 recreate the master rsb when it gets a request from the dir node for
4404 an rsb it doesn't have. */
4405
4406 memset(name, 0, sizeof(name));
4407 memcpy(name, ms->m_extra, len);
4408
4409 hash = jhash(name, len, 0);
4410 b = hash & (ls->ls_rsbtbl_size - 1);
4411
4412 spin_lock(&ls->ls_rsbtbl[b].lock);
4413
4414 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4415 if (rv) {
4416 /* verify the rsb is on keep list per comment above */
4417 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4418 if (rv) {
4419 /* should not happen */
4420 log_error(ls, "receive_remove from %d not found %s",
4421 from_nodeid, name);
4422 spin_unlock(&ls->ls_rsbtbl[b].lock);
4423 return;
4424 }
4425 if (r->res_master_nodeid != from_nodeid) {
4426 /* should not happen */
4427 log_error(ls, "receive_remove keep from %d master %d",
4428 from_nodeid, r->res_master_nodeid);
4429 dlm_print_rsb(r);
4430 spin_unlock(&ls->ls_rsbtbl[b].lock);
4431 return;
4432 }
4433
4434 log_debug(ls, "receive_remove from %d master %d first %x %s",
4435 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4436 name);
4437 spin_unlock(&ls->ls_rsbtbl[b].lock);
4438 return;
4439 }
4440
4441 if (r->res_master_nodeid != from_nodeid) {
4442 log_error(ls, "receive_remove toss from %d master %d",
4443 from_nodeid, r->res_master_nodeid);
4444 dlm_print_rsb(r);
4445 spin_unlock(&ls->ls_rsbtbl[b].lock);
4446 return;
4447 }
4448
4449 if (kref_put(&r->res_ref, kill_rsb)) {
4450 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4451 spin_unlock(&ls->ls_rsbtbl[b].lock);
4452 dlm_free_rsb(r);
4453 } else {
4454 log_error(ls, "receive_remove from %d rsb ref error",
4455 from_nodeid);
4456 dlm_print_rsb(r);
4457 spin_unlock(&ls->ls_rsbtbl[b].lock);
4458 }
e7fd4179
DT		 4459}
4460
8499137d
DT		 4461static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
4462{
4463 do_purge(ls, ms->m_nodeid, ms->m_pid);
4464}
4465
6d40c4a7 4466static int receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4467{
4468 struct dlm_lkb *lkb;
4469 struct dlm_rsb *r;
ef0c2bb0 4470 int error, mstype, result;
c04fecb4 4471 int from_nodeid = ms->m_header.h_nodeid;
e7fd4179
DT		 4472
4473 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4474 if (error)
4475 return error;
e7fd4179 4476
e7fd4179
DT		 4477 r = lkb->lkb_resource;
4478 hold_rsb(r);
4479 lock_rsb(r);
4480
c54e04b0
DT		 4481 error = validate_message(lkb, ms);
4482 if (error)
4483 goto out;
4484
ef0c2bb0
DT		 4485 mstype = lkb->lkb_wait_type;
4486 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4875647a
DT		 4487 if (error) {
4488 log_error(ls, "receive_request_reply %x remote %d %x result %d",
c04fecb4 4489 lkb->lkb_id, from_nodeid, ms->m_lkid, ms->m_result);
4875647a 4490 dlm_dump_rsb(r);
ef0c2bb0 4491 goto out;
4875647a 4492 }
ef0c2bb0 4493
e7fd4179
DT		 4494 /* Optimization: the dir node was also the master, so it took our
4495 lookup as a request and sent request reply instead of lookup reply */
4496 if (mstype == DLM_MSG_LOOKUP) {
c04fecb4
DT		 4497 r->res_master_nodeid = from_nodeid;
4498 r->res_nodeid = from_nodeid;
4499 lkb->lkb_nodeid = from_nodeid;
e7fd4179
DT		 4500 }
4501
ef0c2bb0
DT		 4502 /* this is the value returned from do_request() on the master */
4503 result = ms->m_result;
4504
4505 switch (result) {
e7fd4179 4506 case -EAGAIN:
ef0c2bb0 4507 /* request would block (be queued) on remote master */
e7fd4179
DT		 4508 queue_cast(r, lkb, -EAGAIN);
4509 confirm_master(r, -EAGAIN);
ef0c2bb0 4510 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 4511 break;
4512
4513 case -EINPROGRESS:
4514 case 0:
4515 /* request was queued or granted on remote master */
4516 receive_flags_reply(lkb, ms);
4517 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 4518 if (is_altmode(lkb))
4519 munge_altmode(lkb, ms);
3ae1acf9 4520 if (result) {
e7fd4179 4521 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 4522 add_timeout(lkb);
4523 } else {
e7fd4179
DT		 4524 grant_lock_pc(r, lkb, ms);
4525 queue_cast(r, lkb, 0);
4526 }
ef0c2bb0 4527 confirm_master(r, result);
e7fd4179
DT		 4528 break;
4529
597d0cae 4530 case -EBADR:
e7fd4179
DT		 4531 case -ENOTBLK:
4532 /* find_rsb failed to find rsb or rsb wasn't master */
c04fecb4
DT		 4533 log_limit(ls, "receive_request_reply %x from %d %d "
4534 "master %d dir %d first %x %s", lkb->lkb_id,
4535 from_nodeid, result, r->res_master_nodeid,
4536 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4537
4538 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4539 r->res_master_nodeid != dlm_our_nodeid()) {
4540 /* cause _request_lock->set_master->send_lookup */
4541 r->res_master_nodeid = 0;
4542 r->res_nodeid = -1;
4543 lkb->lkb_nodeid = -1;
4544 }
ef0c2bb0
DT		 4545
4546 if (is_overlap(lkb)) {
4547 /* we'll ignore error in cancel/unlock reply */
4548 queue_cast_overlap(r, lkb);
aec64e1b 4549 confirm_master(r, result);
ef0c2bb0 4550 unhold_lkb(lkb); /* undoes create_lkb() */
c04fecb4 4551 } else {
ef0c2bb0 4552 _request_lock(r, lkb);
c04fecb4
DT		 4553
4554 if (r->res_master_nodeid == dlm_our_nodeid())
4555 confirm_master(r, 0);
4556 }
e7fd4179
DT		 4557 break;
4558
4559 default:
ef0c2bb0
DT		 4560 log_error(ls, "receive_request_reply %x error %d",
4561 lkb->lkb_id, result);
e7fd4179
DT		 4562 }
4563
ef0c2bb0
DT		 4564 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
4565 log_debug(ls, "receive_request_reply %x result %d unlock",
4566 lkb->lkb_id, result);
4567 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4568 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4569 send_unlock(r, lkb);
4570 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
4571 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4572 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4573 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4574 send_cancel(r, lkb);
4575 } else {
4576 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4577 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4578 }
4579 out:
e7fd4179
DT		 4580 unlock_rsb(r);
4581 put_rsb(r);
b3f58d8f 4582 dlm_put_lkb(lkb);
6d40c4a7 4583 return 0;
e7fd4179
DT		 4584}
4585
4586static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4587 struct dlm_message *ms)
4588{
e7fd4179 4589 /* this is the value returned from do_convert() on the master */
ef0c2bb0 4590 switch (ms->m_result) {
e7fd4179
DT		 4591 case -EAGAIN:
4592 /* convert would block (be queued) on remote master */
4593 queue_cast(r, lkb, -EAGAIN);
4594 break;
4595
c85d65e9
DT		 4596 case -EDEADLK:
4597 receive_flags_reply(lkb, ms);
4598 revert_lock_pc(r, lkb);
4599 queue_cast(r, lkb, -EDEADLK);
4600 break;
4601
e7fd4179
DT		 4602 case -EINPROGRESS:
4603 /* convert was queued on remote master */
7d3c1feb
DT		 4604 receive_flags_reply(lkb, ms);
4605 if (is_demoted(lkb))
2a7ce0ed 4606 munge_demoted(lkb);
e7fd4179
DT		 4607 del_lkb(r, lkb);
4608 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 4609 add_timeout(lkb);
e7fd4179
DT		 4610 break;
4611
4612 case 0:
4613 /* convert was granted on remote master */
4614 receive_flags_reply(lkb, ms);
7d3c1feb 4615 if (is_demoted(lkb))
2a7ce0ed 4616 munge_demoted(lkb);
e7fd4179
DT		 4617 grant_lock_pc(r, lkb, ms);
4618 queue_cast(r, lkb, 0);
4619 break;
4620
4621 default:
6d40c4a7
DT		 4622 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4623 lkb->lkb_id, ms->m_header.h_nodeid, ms->m_lkid,
4624 ms->m_result);
4625 dlm_print_rsb(r);
4626 dlm_print_lkb(lkb);
e7fd4179
DT		 4627 }
4628}
4629
4630static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4631{
4632 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4633 int error;
e7fd4179
DT		 4634
4635 hold_rsb(r);
4636 lock_rsb(r);
4637
c54e04b0
DT		 4638 error = validate_message(lkb, ms);
4639 if (error)
4640 goto out;
4641
ef0c2bb0
DT		 4642 /* stub reply can happen with waiters_mutex held */
4643 error = remove_from_waiters_ms(lkb, ms);
4644 if (error)
4645 goto out;
e7fd4179 4646
ef0c2bb0
DT		 4647 __receive_convert_reply(r, lkb, ms);
4648 out:
e7fd4179
DT		 4649 unlock_rsb(r);
4650 put_rsb(r);
4651}
4652
6d40c4a7 4653static int receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4654{
4655 struct dlm_lkb *lkb;
4656 int error;
4657
4658 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4659 if (error)
4660 return error;
e7fd4179 4661
e7fd4179 4662 _receive_convert_reply(lkb, ms);
b3f58d8f 4663 dlm_put_lkb(lkb);
6d40c4a7 4664 return 0;
e7fd4179
DT		 4665}
4666
4667static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4668{
4669 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4670 int error;
e7fd4179
DT		 4671
4672 hold_rsb(r);
4673 lock_rsb(r);
4674
c54e04b0
DT		 4675 error = validate_message(lkb, ms);
4676 if (error)
4677 goto out;
4678
ef0c2bb0
DT		 4679 /* stub reply can happen with waiters_mutex held */
4680 error = remove_from_waiters_ms(lkb, ms);
4681 if (error)
4682 goto out;
4683
e7fd4179
DT		 4684 /* this is the value returned from do_unlock() on the master */
4685
ef0c2bb0 4686 switch (ms->m_result) {
e7fd4179
DT		 4687 case -DLM_EUNLOCK:
4688 receive_flags_reply(lkb, ms);
4689 remove_lock_pc(r, lkb);
4690 queue_cast(r, lkb, -DLM_EUNLOCK);
4691 break;
ef0c2bb0
DT		 4692 case -ENOENT:
4693 break;
e7fd4179 4694 default:
ef0c2bb0
DT		 4695 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4696 lkb->lkb_id, ms->m_result);
e7fd4179 4697 }
ef0c2bb0 4698 out:
e7fd4179
DT		 4699 unlock_rsb(r);
4700 put_rsb(r);
4701}
4702
6d40c4a7 4703static int receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4704{
4705 struct dlm_lkb *lkb;
4706 int error;
4707
4708 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4709 if (error)
4710 return error;
e7fd4179 4711
e7fd4179 4712 _receive_unlock_reply(lkb, ms);
b3f58d8f 4713 dlm_put_lkb(lkb);
6d40c4a7 4714 return 0;
e7fd4179
DT		 4715}
4716
4717static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4718{
4719 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4720 int error;
e7fd4179
DT		 4721
4722 hold_rsb(r);
4723 lock_rsb(r);
4724
c54e04b0
DT		 4725 error = validate_message(lkb, ms);
4726 if (error)
4727 goto out;
4728
ef0c2bb0
DT		 4729 /* stub reply can happen with waiters_mutex held */
4730 error = remove_from_waiters_ms(lkb, ms);
4731 if (error)
4732 goto out;
4733
e7fd4179
DT		 4734 /* this is the value returned from do_cancel() on the master */
4735
ef0c2bb0 4736 switch (ms->m_result) {
e7fd4179
DT		 4737 case -DLM_ECANCEL:
4738 receive_flags_reply(lkb, ms);
4739 revert_lock_pc(r, lkb);
84d8cd69 4740 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 4741 break;
4742 case 0:
e7fd4179
DT		 4743 break;
4744 default:
ef0c2bb0
DT		 4745 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4746 lkb->lkb_id, ms->m_result);
e7fd4179 4747 }
ef0c2bb0 4748 out:
e7fd4179
DT		 4749 unlock_rsb(r);
4750 put_rsb(r);
4751}
4752
6d40c4a7 4753static int receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4754{
4755 struct dlm_lkb *lkb;
4756 int error;
4757
4758 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4759 if (error)
4760 return error;
e7fd4179 4761
e7fd4179 4762 _receive_cancel_reply(lkb, ms);
b3f58d8f 4763 dlm_put_lkb(lkb);
6d40c4a7 4764 return 0;
e7fd4179
DT		 4765}
4766
4767static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
4768{
4769 struct dlm_lkb *lkb;
4770 struct dlm_rsb *r;
4771 int error, ret_nodeid;
c04fecb4 4772 int do_lookup_list = 0;
e7fd4179
DT		 4773
4774 error = find_lkb(ls, ms->m_lkid, &lkb);
4775 if (error) {
6d40c4a7 4776 log_error(ls, "receive_lookup_reply no lkid %x", ms->m_lkid);
e7fd4179
DT		 4777 return;
4778 }
4779
c04fecb4 4780 /* ms->m_result is the value returned by dlm_master_lookup on dir node
e7fd4179 4781 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 4782
4783 r = lkb->lkb_resource;
4784 hold_rsb(r);
4785 lock_rsb(r);
4786
ef0c2bb0
DT		 4787 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4788 if (error)
4789 goto out;
4790
e7fd4179 4791 ret_nodeid = ms->m_nodeid;
c04fecb4
DT		 4792
4793 /* We sometimes receive a request from the dir node for this
4794 rsb before we've received the dir node's loookup_reply for it.
4795 The request from the dir node implies we're the master, so we set
4796 ourself as master in receive_request_reply, and verify here that
4797 we are indeed the master. */
4798
4799 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4800 /* This should never happen */
4801 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4802 "master %d dir %d our %d first %x %s",
4803 lkb->lkb_id, ms->m_header.h_nodeid, ret_nodeid,
4804 r->res_master_nodeid, r->res_dir_nodeid,
4805 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4806 }
4807
e7fd4179 4808 if (ret_nodeid == dlm_our_nodeid()) {
c04fecb4 4809 r->res_master_nodeid = ret_nodeid;
e7fd4179 4810 r->res_nodeid = 0;
c04fecb4 4811 do_lookup_list = 1;
e7fd4179 4812 r->res_first_lkid = 0;
c04fecb4
DT		 4813 } else if (ret_nodeid == -1) {
4814 /* the remote node doesn't believe it's the dir node */
4815 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4816 lkb->lkb_id, ms->m_header.h_nodeid);
4817 r->res_master_nodeid = 0;
4818 r->res_nodeid = -1;
4819 lkb->lkb_nodeid = -1;
e7fd4179 4820 } else {
c04fecb4
DT		 4821 /* set_master() will set lkb_nodeid from r */
4822 r->res_master_nodeid = ret_nodeid;
e7fd4179
DT		 4823 r->res_nodeid = ret_nodeid;
4824 }
4825
ef0c2bb0
DT		 4826 if (is_overlap(lkb)) {
4827 log_debug(ls, "receive_lookup_reply %x unlock %x",
4828 lkb->lkb_id, lkb->lkb_flags);
4829 queue_cast_overlap(r, lkb);
4830 unhold_lkb(lkb); /* undoes create_lkb() */
4831 goto out_list;
4832 }
4833
e7fd4179
DT		 4834 _request_lock(r, lkb);
4835
ef0c2bb0 4836 out_list:
c04fecb4 4837 if (do_lookup_list)
e7fd4179 4838 process_lookup_list(r);
ef0c2bb0 4839 out:
e7fd4179
DT		 4840 unlock_rsb(r);
4841 put_rsb(r);
b3f58d8f 4842 dlm_put_lkb(lkb);
e7fd4179
DT		 4843}
4844
6d40c4a7
DT		 4845static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4846 uint32_t saved_seq)
e7fd4179 4847{
6d40c4a7
DT		 4848 int error = 0, noent = 0;
4849
46b43eed 4850 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
c04fecb4 4851 log_limit(ls, "receive %d from non-member %d %x %x %d",
46b43eed
DT		 4852 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4853 ms->m_remid, ms->m_result);
4854 return;
4855 }
4856
e7fd4179
DT		 4857 switch (ms->m_type) {
4858
4859 /* messages sent to a master node */
4860
4861 case DLM_MSG_REQUEST:
6d40c4a7 4862 error = receive_request(ls, ms);
e7fd4179
DT		 4863 break;
4864
4865 case DLM_MSG_CONVERT:
6d40c4a7 4866 error = receive_convert(ls, ms);
e7fd4179
DT		 4867 break;
4868
4869 case DLM_MSG_UNLOCK:
6d40c4a7 4870 error = receive_unlock(ls, ms);
e7fd4179
DT		 4871 break;
4872
4873 case DLM_MSG_CANCEL:
6d40c4a7
DT		 4874 noent = 1;
4875 error = receive_cancel(ls, ms);
e7fd4179
DT		 4876 break;
4877
4878 /* messages sent from a master node (replies to above) */
4879
4880 case DLM_MSG_REQUEST_REPLY:
6d40c4a7 4881 error = receive_request_reply(ls, ms);
e7fd4179
DT		 4882 break;
4883
4884 case DLM_MSG_CONVERT_REPLY:
6d40c4a7 4885 error = receive_convert_reply(ls, ms);
e7fd4179
DT		 4886 break;
4887
4888 case DLM_MSG_UNLOCK_REPLY:
6d40c4a7 4889 error = receive_unlock_reply(ls, ms);
e7fd4179
DT		 4890 break;
4891
4892 case DLM_MSG_CANCEL_REPLY:
6d40c4a7 4893 error = receive_cancel_reply(ls, ms);
e7fd4179
DT		 4894 break;
4895
4896 /* messages sent from a master node (only two types of async msg) */
4897
4898 case DLM_MSG_GRANT:
6d40c4a7
DT		 4899 noent = 1;
4900 error = receive_grant(ls, ms);
e7fd4179
DT		 4901 break;
4902
4903 case DLM_MSG_BAST:
6d40c4a7
DT		 4904 noent = 1;
4905 error = receive_bast(ls, ms);
e7fd4179
DT		 4906 break;
4907
4908 /* messages sent to a dir node */
4909
4910 case DLM_MSG_LOOKUP:
4911 receive_lookup(ls, ms);
4912 break;
4913
4914 case DLM_MSG_REMOVE:
4915 receive_remove(ls, ms);
4916 break;
4917
4918 /* messages sent from a dir node (remove has no reply) */
4919
4920 case DLM_MSG_LOOKUP_REPLY:
4921 receive_lookup_reply(ls, ms);
4922 break;
4923
8499137d
DT		 4924 /* other messages */
4925
4926 case DLM_MSG_PURGE:
4927 receive_purge(ls, ms);
4928 break;
4929
e7fd4179
DT		 4930 default:
4931 log_error(ls, "unknown message type %d", ms->m_type);
4932 }
6d40c4a7
DT		 4933
4934 /*
4935 * When checking for ENOENT, we're checking the result of
4936 * find_lkb(m_remid):
4937 *
4938 * The lock id referenced in the message wasn't found. This may
4939 * happen in normal usage for the async messages and cancel, so
4940 * only use log_debug for them.
4941 *
4875647a 4942 * Some errors are expected and normal.
6d40c4a7
DT		 4943 */
4944
4945 if (error == -ENOENT && noent) {
4875647a 4946 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4947 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4948 ms->m_lkid, saved_seq);
4949 } else if (error == -ENOENT) {
4875647a 4950 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4951 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4952 ms->m_lkid, saved_seq);
4953
4954 if (ms->m_type == DLM_MSG_CONVERT)
4955 dlm_dump_rsb_hash(ls, ms->m_hash);
4956 }
4875647a
DT		 4957
4958 if (error == -EINVAL) {
4959 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4960 "saved_seq %u",
4961 ms->m_type, ms->m_header.h_nodeid,
4962 ms->m_lkid, ms->m_remid, saved_seq);
4963 }
e7fd4179
DT		 4964}
4965
c36258b5
DT		 4966/* If the lockspace is in recovery mode (locking stopped), then normal
4967 messages are saved on the requestqueue for processing after recovery is
4968 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4969 messages off the requestqueue before we process new ones. This occurs right
4970 after recovery completes when we transition from saving all messages on
4971 requestqueue, to processing all the saved messages, to processing new
4972 messages as they arrive. */
e7fd4179 4973
c36258b5
DT		 4974static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4975 int nodeid)
4976{
4977 if (dlm_locking_stopped(ls)) {
c04fecb4
DT		 4978 /* If we were a member of this lockspace, left, and rejoined,
4979 other nodes may still be sending us messages from the
4980 lockspace generation before we left. */
4981 if (!ls->ls_generation) {
4982 log_limit(ls, "receive %d from %d ignore old gen",
4983 ms->m_type, nodeid);
4984 return;
4985 }
4986
8b0d8e03 4987 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 4988 } else {
4989 dlm_wait_requestqueue(ls);
6d40c4a7 4990 _receive_message(ls, ms, 0);
c36258b5
DT		 4991 }
4992}
4993
4994/* This is called by dlm_recoverd to process messages that were saved on
4995 the requestqueue. */
4996
6d40c4a7
DT		 4997void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
4998 uint32_t saved_seq)
c36258b5 4999{
6d40c4a7 5000 _receive_message(ls, ms, saved_seq);
c36258b5
DT		 5001}
5002
5003/* This is called by the midcomms layer when something is received for
5004 the lockspace. It could be either a MSG (normal message sent as part of
5005 standard locking activity) or an RCOM (recovery message sent as part of
5006 lockspace recovery). */
5007
eef7d739 5008void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 5009{
eef7d739 5010 struct dlm_header *hd = &p->header;
c36258b5
DT		 5011 struct dlm_ls *ls;
5012 int type = 0;
5013
5014 switch (hd->h_cmd) {
5015 case DLM_MSG:
eef7d739
AV		 5016 dlm_message_in(&p->message);
5017 type = p->message.m_type;
c36258b5
DT		 5018 break;
5019 case DLM_RCOM:
eef7d739
AV		 5020 dlm_rcom_in(&p->rcom);
5021 type = p->rcom.rc_type;
c36258b5
DT		 5022 break;
5023 default:
5024 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
5025 return;
5026 }
5027
5028 if (hd->h_nodeid != nodeid) {
5029 log_print("invalid h_nodeid %d from %d lockspace %x",
5030 hd->h_nodeid, nodeid, hd->h_lockspace);
5031 return;
5032 }
5033
5034 ls = dlm_find_lockspace_global(hd->h_lockspace);
5035 if (!ls) {
4875647a
DT		 5036 if (dlm_config.ci_log_debug) {
5037 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
5038 "%u from %d cmd %d type %d\n",
5039 hd->h_lockspace, nodeid, hd->h_cmd, type);
5040 }
c36258b5
DT		 5041
5042 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 5043 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 5044 return;
5045 }
5046
5047 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
5048 be inactive (in this ls) before transitioning to recovery mode */
5049
5050 down_read(&ls->ls_recv_active);
5051 if (hd->h_cmd == DLM_MSG)
eef7d739 5052 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 5053 else
eef7d739 5054 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 5055 up_read(&ls->ls_recv_active);
5056
5057 dlm_put_lockspace(ls);
5058}
e7fd4179 5059
2a7ce0ed
DT		 5060static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
5061 struct dlm_message *ms_stub)
e7fd4179
DT		 5062{
5063 if (middle_conversion(lkb)) {
5064 hold_lkb(lkb);
2a7ce0ed
DT		 5065 memset(ms_stub, 0, sizeof(struct dlm_message));
5066 ms_stub->m_flags = DLM_IFL_STUB_MS;
5067 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
5068 ms_stub->m_result = -EINPROGRESS;
5069 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5070 _receive_convert_reply(lkb, ms_stub);
e7fd4179
DT		 5071
5072 /* Same special case as in receive_rcom_lock_args() */
5073 lkb->lkb_grmode = DLM_LOCK_IV;
5074 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
5075 unhold_lkb(lkb);
5076
5077 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
5078 lkb->lkb_flags |= DLM_IFL_RESEND;
5079 }
5080
5081 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
5082 conversions are async; there's no reply from the remote master */
5083}
5084
5085/* A waiting lkb needs recovery if the master node has failed, or
5086 the master node is changing (only when no directory is used) */
5087
13ef1111
DT		 5088static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
5089 int dir_nodeid)
e7fd4179 5090{
4875647a 5091 if (dlm_no_directory(ls))
13ef1111
DT		 5092 return 1;
5093
4875647a 5094 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
e7fd4179
DT		 5095 return 1;
5096
5097 return 0;
5098}
5099
5100/* Recovery for locks that are waiting for replies from nodes that are now
5101 gone. We can just complete unlocks and cancels by faking a reply from the
5102 dead node. Requests and up-conversions we flag to be resent after
5103 recovery. Down-conversions can just be completed with a fake reply like
5104 unlocks. Conversions between PR and CW need special attention. */
5105
5106void dlm_recover_waiters_pre(struct dlm_ls *ls)
5107{
5108 struct dlm_lkb *lkb, *safe;
2a7ce0ed 5109 struct dlm_message *ms_stub;
601342ce 5110 int wait_type, stub_unlock_result, stub_cancel_result;
13ef1111 5111 int dir_nodeid;
e7fd4179 5112
a22ca480 5113 ms_stub = kmalloc(sizeof(struct dlm_message), GFP_KERNEL);
2a7ce0ed
DT		 5114 if (!ms_stub) {
5115 log_error(ls, "dlm_recover_waiters_pre no mem");
5116 return;
5117 }
5118
90135925 5119 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5120
5121 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
2a7ce0ed 5122
13ef1111
DT		 5123 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
5124
2a7ce0ed
DT		 5125 /* exclude debug messages about unlocks because there can be so
5126 many and they aren't very interesting */
5127
5128 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
13ef1111
DT		 5129 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5130 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
5131 lkb->lkb_id,
5132 lkb->lkb_remid,
5133 lkb->lkb_wait_type,
5134 lkb->lkb_resource->res_nodeid,
5135 lkb->lkb_nodeid,
5136 lkb->lkb_wait_nodeid,
5137 dir_nodeid);
2a7ce0ed 5138 }
e7fd4179
DT		 5139
5140 /* all outstanding lookups, regardless of destination will be
5141 resent after recovery is done */
5142
5143 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
5144 lkb->lkb_flags |= DLM_IFL_RESEND;
5145 continue;
5146 }
5147
13ef1111 5148 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
e7fd4179
DT		 5149 continue;
5150
601342ce
DT		 5151 wait_type = lkb->lkb_wait_type;
5152 stub_unlock_result = -DLM_EUNLOCK;
5153 stub_cancel_result = -DLM_ECANCEL;
5154
5155 /* Main reply may have been received leaving a zero wait_type,
5156 but a reply for the overlapping op may not have been
5157 received. In that case we need to fake the appropriate
5158 reply for the overlap op. */
5159
5160 if (!wait_type) {
5161 if (is_overlap_cancel(lkb)) {
5162 wait_type = DLM_MSG_CANCEL;
5163 if (lkb->lkb_grmode == DLM_LOCK_IV)
5164 stub_cancel_result = 0;
5165 }
5166 if (is_overlap_unlock(lkb)) {
5167 wait_type = DLM_MSG_UNLOCK;
5168 if (lkb->lkb_grmode == DLM_LOCK_IV)
5169 stub_unlock_result = -ENOENT;
5170 }
5171
5172 log_debug(ls, "rwpre overlap %x %x %d %d %d",
5173 lkb->lkb_id, lkb->lkb_flags, wait_type,
5174 stub_cancel_result, stub_unlock_result);
5175 }
5176
5177 switch (wait_type) {
e7fd4179
DT		 5178
5179 case DLM_MSG_REQUEST:
5180 lkb->lkb_flags |= DLM_IFL_RESEND;
5181 break;
5182
5183 case DLM_MSG_CONVERT:
2a7ce0ed 5184 recover_convert_waiter(ls, lkb, ms_stub);
e7fd4179
DT		 5185 break;
5186
5187 case DLM_MSG_UNLOCK:
5188 hold_lkb(lkb);
2a7ce0ed
DT		 5189 memset(ms_stub, 0, sizeof(struct dlm_message));
5190 ms_stub->m_flags = DLM_IFL_STUB_MS;
5191 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
5192 ms_stub->m_result = stub_unlock_result;
5193 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5194 _receive_unlock_reply(lkb, ms_stub);
b3f58d8f 5195 dlm_put_lkb(lkb);
e7fd4179
DT		 5196 break;
5197
5198 case DLM_MSG_CANCEL:
5199 hold_lkb(lkb);
2a7ce0ed
DT		 5200 memset(ms_stub, 0, sizeof(struct dlm_message));
5201 ms_stub->m_flags = DLM_IFL_STUB_MS;
5202 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
5203 ms_stub->m_result = stub_cancel_result;
5204 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5205 _receive_cancel_reply(lkb, ms_stub);
b3f58d8f 5206 dlm_put_lkb(lkb);
e7fd4179
DT		 5207 break;
5208
5209 default:
601342ce
DT		 5210 log_error(ls, "invalid lkb wait_type %d %d",
5211 lkb->lkb_wait_type, wait_type);
e7fd4179 5212 }
81456807 5213 schedule();
e7fd4179 5214 }
90135925 5215 mutex_unlock(&ls->ls_waiters_mutex);
2a7ce0ed 5216 kfree(ms_stub);
e7fd4179
DT		 5217}
5218
ef0c2bb0 5219static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 5220{
5221 struct dlm_lkb *lkb;
ef0c2bb0 5222 int found = 0;
e7fd4179 5223
90135925 5224 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5225 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
5226 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 5227 hold_lkb(lkb);
5228 found = 1;
e7fd4179
DT		 5229 break;
5230 }
5231 }
90135925 5232 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 5233
ef0c2bb0 5234 if (!found)
e7fd4179 5235 lkb = NULL;
ef0c2bb0 5236 return lkb;
e7fd4179
DT		 5237}
5238
5239/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5240 master or dir-node for r. Processing the lkb may result in it being placed
5241 back on waiters. */
5242
ef0c2bb0
DT		 5243/* We do this after normal locking has been enabled and any saved messages
5244 (in requestqueue) have been processed. We should be confident that at
5245 this point we won't get or process a reply to any of these waiting
5246 operations. But, new ops may be coming in on the rsbs/locks here from
5247 userspace or remotely. */
5248
5249/* there may have been an overlap unlock/cancel prior to recovery or after
5250 recovery. if before, the lkb may still have a pos wait_count; if after, the
5251 overlap flag would just have been set and nothing new sent. we can be
5252 confident here than any replies to either the initial op or overlap ops
5253 prior to recovery have been received. */
5254
e7fd4179
DT		 5255int dlm_recover_waiters_post(struct dlm_ls *ls)
5256{
5257 struct dlm_lkb *lkb;
5258 struct dlm_rsb *r;
ef0c2bb0 5259 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 5260
5261 while (1) {
5262 if (dlm_locking_stopped(ls)) {
5263 log_debug(ls, "recover_waiters_post aborted");
5264 error = -EINTR;
5265 break;
5266 }
5267
ef0c2bb0
DT		 5268 lkb = find_resend_waiter(ls);
5269 if (!lkb)
e7fd4179
DT		 5270 break;
5271
5272 r = lkb->lkb_resource;
ef0c2bb0
DT		 5273 hold_rsb(r);
5274 lock_rsb(r);
5275
5276 mstype = lkb->lkb_wait_type;
5277 oc = is_overlap_cancel(lkb);
5278 ou = is_overlap_unlock(lkb);
5279 err = 0;
e7fd4179 5280
13ef1111
DT		 5281 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5282 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5283 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5284 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5285 dlm_dir_nodeid(r), oc, ou);
e7fd4179 5286
ef0c2bb0
DT		 5287 /* At this point we assume that we won't get a reply to any
5288 previous op or overlap op on this lock. First, do a big
5289 remove_from_waiters() for all previous ops. */
5290
5291 lkb->lkb_flags &= ~DLM_IFL_RESEND;
5292 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
5293 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
5294 lkb->lkb_wait_type = 0;
5295 lkb->lkb_wait_count = 0;
5296 mutex_lock(&ls->ls_waiters_mutex);
5297 list_del_init(&lkb->lkb_wait_reply);
5298 mutex_unlock(&ls->ls_waiters_mutex);
5299 unhold_lkb(lkb); /* for waiters list */
5300
5301 if (oc || ou) {
5302 /* do an unlock or cancel instead of resending */
5303 switch (mstype) {
5304 case DLM_MSG_LOOKUP:
5305 case DLM_MSG_REQUEST:
5306 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5307 -DLM_ECANCEL);
5308 unhold_lkb(lkb); /* undoes create_lkb() */
5309 break;
5310 case DLM_MSG_CONVERT:
5311 if (oc) {
5312 queue_cast(r, lkb, -DLM_ECANCEL);
5313 } else {
5314 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5315 _unlock_lock(r, lkb);
5316 }
5317 break;
5318 default:
5319 err = 1;
5320 }
5321 } else {
5322 switch (mstype) {
5323 case DLM_MSG_LOOKUP:
5324 case DLM_MSG_REQUEST:
5325 _request_lock(r, lkb);
5326 if (is_master(r))
5327 confirm_master(r, 0);
5328 break;
5329 case DLM_MSG_CONVERT:
5330 _convert_lock(r, lkb);
5331 break;
5332 default:
5333 err = 1;
5334 }
e7fd4179 5335 }
ef0c2bb0 5336
13ef1111
DT		 5337 if (err) {
5338 log_error(ls, "waiter %x msg %d r_nodeid %d "
5339 "dir_nodeid %d overlap %d %d",
5340 lkb->lkb_id, mstype, r->res_nodeid,
5341 dlm_dir_nodeid(r), oc, ou);
5342 }
ef0c2bb0
DT		 5343 unlock_rsb(r);
5344 put_rsb(r);
5345 dlm_put_lkb(lkb);
e7fd4179
DT		 5346 }
5347
5348 return error;
5349}
5350
4875647a
DT		 5351static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5352 struct list_head *list)
e7fd4179 5353{
e7fd4179
DT		 5354 struct dlm_lkb *lkb, *safe;
5355
4875647a
DT		 5356 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5357 if (!is_master_copy(lkb))
5358 continue;
5359
5360 /* don't purge lkbs we've added in recover_master_copy for
5361 the current recovery seq */
5362
5363 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5364 continue;
5365
5366 del_lkb(r, lkb);
5367
5368 /* this put should free the lkb */
5369 if (!dlm_put_lkb(lkb))
5370 log_error(ls, "purged mstcpy lkb not released");
e7fd4179
DT		 5371 }
5372}
5373
4875647a 5374void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
e7fd4179 5375{
4875647a 5376 struct dlm_ls *ls = r->res_ls;
e7fd4179 5377
4875647a
DT		 5378 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5379 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5380 purge_mstcpy_list(ls, r, &r->res_waitqueue);
e7fd4179
DT		 5381}
5382
4875647a
DT		 5383static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5384 struct list_head *list,
5385 int nodeid_gone, unsigned int *count)
e7fd4179 5386{
4875647a 5387 struct dlm_lkb *lkb, *safe;
e7fd4179 5388
4875647a
DT		 5389 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5390 if (!is_master_copy(lkb))
5391 continue;
5392
5393 if ((lkb->lkb_nodeid == nodeid_gone) ||
5394 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5395
5396 del_lkb(r, lkb);
5397
5398 /* this put should free the lkb */
5399 if (!dlm_put_lkb(lkb))
5400 log_error(ls, "purged dead lkb not released");
5401
5402 rsb_set_flag(r, RSB_RECOVER_GRANT);
5403
5404 (*count)++;
5405 }
5406 }
e7fd4179
DT		 5407}
5408
5409/* Get rid of locks held by nodes that are gone. */
5410
4875647a 5411void dlm_recover_purge(struct dlm_ls *ls)
e7fd4179
DT		 5412{
5413 struct dlm_rsb *r;
4875647a
DT		 5414 struct dlm_member *memb;
5415 int nodes_count = 0;
5416 int nodeid_gone = 0;
5417 unsigned int lkb_count = 0;
5418
5419 /* cache one removed nodeid to optimize the common
5420 case of a single node removed */
5421
5422 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5423 nodes_count++;
5424 nodeid_gone = memb->nodeid;
5425 }
e7fd4179 5426
4875647a
DT		 5427 if (!nodes_count)
5428 return;
e7fd4179
DT		 5429
5430 down_write(&ls->ls_root_sem);
5431 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5432 hold_rsb(r);
5433 lock_rsb(r);
4875647a
DT		 5434 if (is_master(r)) {
5435 purge_dead_list(ls, r, &r->res_grantqueue,
5436 nodeid_gone, &lkb_count);
5437 purge_dead_list(ls, r, &r->res_convertqueue,
5438 nodeid_gone, &lkb_count);
5439 purge_dead_list(ls, r, &r->res_waitqueue,
5440 nodeid_gone, &lkb_count);
5441 }
e7fd4179
DT		 5442 unlock_rsb(r);
5443 unhold_rsb(r);
4875647a 5444 cond_resched();
e7fd4179
DT		 5445 }
5446 up_write(&ls->ls_root_sem);
5447
4875647a
DT		 5448 if (lkb_count)
5449 log_debug(ls, "dlm_recover_purge %u locks for %u nodes",
5450 lkb_count, nodes_count);
e7fd4179
DT		 5451}
5452
4875647a 5453static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
97a35d1e 5454{
9beb3bf5 5455 struct rb_node *n;
4875647a 5456 struct dlm_rsb *r;
97a35d1e 5457
c7be761a 5458 spin_lock(&ls->ls_rsbtbl[bucket].lock);
9beb3bf5
BP		 5459 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5460 r = rb_entry(n, struct dlm_rsb, res_hashnode);
4875647a
DT		 5461
5462 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5463 continue;
c503a621
DT		 5464 if (!is_master(r)) {
5465 rsb_clear_flag(r, RSB_RECOVER_GRANT);
97a35d1e 5466 continue;
c503a621 5467 }
97a35d1e 5468 hold_rsb(r);
4875647a
DT		 5469 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5470 return r;
97a35d1e 5471 }
c7be761a 5472 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
4875647a 5473 return NULL;
97a35d1e
DT		 5474}
5475
4875647a
DT		 5476/*
5477 * Attempt to grant locks on resources that we are the master of.
5478 * Locks may have become grantable during recovery because locks
5479 * from departed nodes have been purged (or not rebuilt), allowing
5480 * previously blocked locks to now be granted. The subset of rsb's
5481 * we are interested in are those with lkb's on either the convert or
5482 * waiting queues.
5483 *
5484 * Simplest would be to go through each master rsb and check for non-empty
5485 * convert or waiting queues, and attempt to grant on those rsbs.
5486 * Checking the queues requires lock_rsb, though, for which we'd need
5487 * to release the rsbtbl lock. This would make iterating through all
5488 * rsb's very inefficient. So, we rely on earlier recovery routines
5489 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5490 * locks for.
5491 */
5492
5493void dlm_recover_grant(struct dlm_ls *ls)
e7fd4179
DT		 5494{
5495 struct dlm_rsb *r;
2b4e926a 5496 int bucket = 0;
4875647a
DT		 5497 unsigned int count = 0;
5498 unsigned int rsb_count = 0;
5499 unsigned int lkb_count = 0;
e7fd4179 5500
2b4e926a 5501 while (1) {
4875647a 5502 r = find_grant_rsb(ls, bucket);
2b4e926a
DT		 5503 if (!r) {
5504 if (bucket == ls->ls_rsbtbl_size - 1)
5505 break;
5506 bucket++;
97a35d1e 5507 continue;
2b4e926a 5508 }
4875647a
DT		 5509 rsb_count++;
5510 count = 0;
97a35d1e 5511 lock_rsb(r);
c503a621 5512 /* the RECOVER_GRANT flag is checked in the grant path */
4875647a 5513 grant_pending_locks(r, &count);
c503a621 5514 rsb_clear_flag(r, RSB_RECOVER_GRANT);
4875647a
DT		 5515 lkb_count += count;
5516 confirm_master(r, 0);
97a35d1e
DT		 5517 unlock_rsb(r);
5518 put_rsb(r);
4875647a 5519 cond_resched();
e7fd4179 5520 }
4875647a
DT		 5521
5522 if (lkb_count)
5523 log_debug(ls, "dlm_recover_grant %u locks on %u resources",
5524 lkb_count, rsb_count);
e7fd4179
DT		 5525}
5526
5527static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5528 uint32_t remid)
5529{
5530 struct dlm_lkb *lkb;
5531
5532 list_for_each_entry(lkb, head, lkb_statequeue) {
5533 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5534 return lkb;
5535 }
5536 return NULL;
5537}
5538
5539static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5540 uint32_t remid)
5541{
5542 struct dlm_lkb *lkb;
5543
5544 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5545 if (lkb)
5546 return lkb;
5547 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5548 if (lkb)
5549 return lkb;
5550 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5551 if (lkb)
5552 return lkb;
5553 return NULL;
5554}
5555
ae773d0b 5556/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5557static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5558 struct dlm_rsb *r, struct dlm_rcom *rc)
5559{
5560 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 5561
5562 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 5563 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5564 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5565 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5566 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 5567 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 5568 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 5569 lkb->lkb_rqmode = rl->rl_rqmode;
5570 lkb->lkb_grmode = rl->rl_grmode;
5571 /* don't set lkb_status because add_lkb wants to itself */
5572
8304d6f2
DT		 5573 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5574 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 5575
e7fd4179 5576 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 5577 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
5578 sizeof(struct rcom_lock);
5579 if (lvblen > ls->ls_lvblen)
5580 return -EINVAL;
52bda2b5 5581 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 5582 if (!lkb->lkb_lvbptr)
5583 return -ENOMEM;
e7fd4179
DT		 5584 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5585 }
5586
5587 /* Conversions between PR and CW (middle modes) need special handling.
5588 The real granted mode of these converting locks cannot be determined
5589 until all locks have been rebuilt on the rsb (recover_conversion) */
5590
163a1859
AV		 5591 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5592 middle_conversion(lkb)) {
e7fd4179
DT		 5593 rl->rl_status = DLM_LKSTS_CONVERT;
5594 lkb->lkb_grmode = DLM_LOCK_IV;
5595 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5596 }
5597
5598 return 0;
5599}
5600
5601/* This lkb may have been recovered in a previous aborted recovery so we need
5602 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5603 If so we just send back a standard reply. If not, we create a new lkb with
5604 the given values and send back our lkid. We send back our lkid by sending
5605 back the rcom_lock struct we got but with the remid field filled in. */
5606
ae773d0b 5607/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5608int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5609{
5610 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5611 struct dlm_rsb *r;
5612 struct dlm_lkb *lkb;
6d40c4a7 5613 uint32_t remid = 0;
c04fecb4 5614 int from_nodeid = rc->rc_header.h_nodeid;
e7fd4179
DT		 5615 int error;
5616
5617 if (rl->rl_parent_lkid) {
5618 error = -EOPNOTSUPP;
5619 goto out;
5620 }
5621
6d40c4a7
DT		 5622 remid = le32_to_cpu(rl->rl_lkid);
5623
4875647a
DT		 5624 /* In general we expect the rsb returned to be R_MASTER, but we don't
5625 have to require it. Recovery of masters on one node can overlap
5626 recovery of locks on another node, so one node can send us MSTCPY
5627 locks before we've made ourselves master of this rsb. We can still
5628 add new MSTCPY locks that we receive here without any harm; when
5629 we make ourselves master, dlm_recover_masters() won't touch the
5630 MSTCPY locks we've received early. */
5631
c04fecb4
DT		 5632 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5633 from_nodeid, R_RECEIVE_RECOVER, &r);
e7fd4179
DT		 5634 if (error)
5635 goto out;
5636
c04fecb4
DT		 5637 lock_rsb(r);
5638
4875647a
DT		 5639 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5640 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
c04fecb4 5641 from_nodeid, remid);
4875647a 5642 error = -EBADR;
c04fecb4 5643 goto out_unlock;
4875647a
DT		 5644 }
5645
c04fecb4 5646 lkb = search_remid(r, from_nodeid, remid);
e7fd4179
DT		 5647 if (lkb) {
5648 error = -EEXIST;
5649 goto out_remid;
5650 }
5651
5652 error = create_lkb(ls, &lkb);
5653 if (error)
5654 goto out_unlock;
5655
5656 error = receive_rcom_lock_args(ls, lkb, r, rc);
5657 if (error) {
b3f58d8f 5658 __put_lkb(ls, lkb);
e7fd4179
DT		 5659 goto out_unlock;
5660 }
5661
5662 attach_lkb(r, lkb);
5663 add_lkb(r, lkb, rl->rl_status);
5664 error = 0;
4875647a
DT		 5665 ls->ls_recover_locks_in++;
5666
5667 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5668 rsb_set_flag(r, RSB_RECOVER_GRANT);
e7fd4179
DT		 5669
5670 out_remid:
5671 /* this is the new value returned to the lock holder for
5672 saving in its process-copy lkb */
163a1859 5673 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179 5674
4875647a
DT		 5675 lkb->lkb_recover_seq = ls->ls_recover_seq;
5676
e7fd4179
DT		 5677 out_unlock:
5678 unlock_rsb(r);
5679 put_rsb(r);
5680 out:
6d40c4a7
DT		 5681 if (error && error != -EEXIST)
5682 log_debug(ls, "dlm_recover_master_copy remote %d %x error %d",
c04fecb4 5683 from_nodeid, remid, error);
163a1859 5684 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 5685 return error;
5686}
5687
ae773d0b 5688/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5689int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5690{
5691 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5692 struct dlm_rsb *r;
5693 struct dlm_lkb *lkb;
6d40c4a7
DT		 5694 uint32_t lkid, remid;
5695 int error, result;
5696
5697 lkid = le32_to_cpu(rl->rl_lkid);
5698 remid = le32_to_cpu(rl->rl_remid);
5699 result = le32_to_cpu(rl->rl_result);
e7fd4179 5700
6d40c4a7 5701 error = find_lkb(ls, lkid, &lkb);
e7fd4179 5702 if (error) {
6d40c4a7
DT		 5703 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5704 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5705 return error;
5706 }
5707
4875647a
DT		 5708 r = lkb->lkb_resource;
5709 hold_rsb(r);
5710 lock_rsb(r);
5711
6d40c4a7
DT		 5712 if (!is_process_copy(lkb)) {
5713 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5714 lkid, rc->rc_header.h_nodeid, remid, result);
4875647a
DT		 5715 dlm_dump_rsb(r);
5716 unlock_rsb(r);
5717 put_rsb(r);
5718 dlm_put_lkb(lkb);
6d40c4a7
DT		 5719 return -EINVAL;
5720 }
e7fd4179 5721
6d40c4a7 5722 switch (result) {
dc200a88
DT		 5723 case -EBADR:
5724 /* There's a chance the new master received our lock before
5725 dlm_recover_master_reply(), this wouldn't happen if we did
5726 a barrier between recover_masters and recover_locks. */
6d40c4a7
DT		 5727
5728 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5729 lkid, rc->rc_header.h_nodeid, remid, result);
5730
dc200a88
DT		 5731 dlm_send_rcom_lock(r, lkb);
5732 goto out;
e7fd4179 5733 case -EEXIST:
e7fd4179 5734 case 0:
6d40c4a7 5735 lkb->lkb_remid = remid;
e7fd4179
DT		 5736 break;
5737 default:
6d40c4a7
DT		 5738 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5739 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5740 }
5741
5742 /* an ack for dlm_recover_locks() which waits for replies from
5743 all the locks it sends to new masters */
5744 dlm_recovered_lock(r);
dc200a88 5745 out:
e7fd4179
DT		 5746 unlock_rsb(r);
5747 put_rsb(r);
b3f58d8f 5748 dlm_put_lkb(lkb);
e7fd4179
DT		 5749
5750 return 0;
5751}
5752
597d0cae
DT		 5753int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5754 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 5755 unsigned long timeout_cs)
597d0cae
DT		 5756{
5757 struct dlm_lkb *lkb;
5758 struct dlm_args args;
5759 int error;
5760
85e86edf 5761 dlm_lock_recovery(ls);
597d0cae
DT		 5762
5763 error = create_lkb(ls, &lkb);
5764 if (error) {
5765 kfree(ua);
5766 goto out;
5767 }
5768
5769 if (flags & DLM_LKF_VALBLK) {
573c24c4 5770 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5771 if (!ua->lksb.sb_lvbptr) {
5772 kfree(ua);
5773 __put_lkb(ls, lkb);
5774 error = -ENOMEM;
5775 goto out;
5776 }
5777 }
5778
52bda2b5 5779 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 5780 When DLM_IFL_USER is set, the dlm knows that this is a userspace
5781 lock and that lkb_astparam is the dlm_user_args structure. */
5782
d7db923e 5783 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 5784 fake_astfn, ua, fake_bastfn, &args);
597d0cae 5785 lkb->lkb_flags |= DLM_IFL_USER;
597d0cae
DT		 5786
5787 if (error) {
5788 __put_lkb(ls, lkb);
5789 goto out;
5790 }
5791
5792 error = request_lock(ls, lkb, name, namelen, &args);
5793
5794 switch (error) {
5795 case 0:
5796 break;
5797 case -EINPROGRESS:
5798 error = 0;
5799 break;
5800 case -EAGAIN:
5801 error = 0;
5802 /* fall through */
5803 default:
5804 __put_lkb(ls, lkb);
5805 goto out;
5806 }
5807
5808 /* add this new lkb to the per-process list of locks */
5809 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 5810 hold_lkb(lkb);
597d0cae
DT		 5811 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5812 spin_unlock(&ua->proc->locks_spin);
5813 out:
85e86edf 5814 dlm_unlock_recovery(ls);
597d0cae
DT		 5815 return error;
5816}
5817
5818int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 5819 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
5820 unsigned long timeout_cs)
597d0cae
DT		 5821{
5822 struct dlm_lkb *lkb;
5823 struct dlm_args args;
5824 struct dlm_user_args *ua;
5825 int error;
5826
85e86edf 5827 dlm_lock_recovery(ls);
597d0cae
DT		 5828
5829 error = find_lkb(ls, lkid, &lkb);
5830 if (error)
5831 goto out;
5832
5833 /* user can change the params on its lock when it converts it, or
5834 add an lvb that didn't exist before */
5835
d292c0cc 5836 ua = lkb->lkb_ua;
597d0cae
DT		 5837
5838 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
573c24c4 5839 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5840 if (!ua->lksb.sb_lvbptr) {
5841 error = -ENOMEM;
5842 goto out_put;
5843 }
5844 }
5845 if (lvb_in && ua->lksb.sb_lvbptr)
5846 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5847
d7db923e 5848 ua->xid = ua_tmp->xid;
597d0cae
DT		 5849 ua->castparam = ua_tmp->castparam;
5850 ua->castaddr = ua_tmp->castaddr;
5851 ua->bastparam = ua_tmp->bastparam;
5852 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 5853 ua->user_lksb = ua_tmp->user_lksb;
597d0cae 5854
d7db923e 5855 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 5856 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 5857 if (error)
5858 goto out_put;
5859
5860 error = convert_lock(ls, lkb, &args);
5861
c85d65e9 5862 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 5863 error = 0;
5864 out_put:
5865 dlm_put_lkb(lkb);
5866 out:
85e86edf 5867 dlm_unlock_recovery(ls);
597d0cae
DT		 5868 kfree(ua_tmp);
5869 return error;
5870}
5871
5872int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5873 uint32_t flags, uint32_t lkid, char *lvb_in)
5874{
5875 struct dlm_lkb *lkb;
5876 struct dlm_args args;
5877 struct dlm_user_args *ua;
5878 int error;
5879
85e86edf 5880 dlm_lock_recovery(ls);
597d0cae
DT		 5881
5882 error = find_lkb(ls, lkid, &lkb);
5883 if (error)
5884 goto out;
5885
d292c0cc 5886 ua = lkb->lkb_ua;
597d0cae
DT		 5887
5888 if (lvb_in && ua->lksb.sb_lvbptr)
5889 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 5890 if (ua_tmp->castparam)
5891 ua->castparam = ua_tmp->castparam;
cc346d55 5892 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 5893
5894 error = set_unlock_args(flags, ua, &args);
5895 if (error)
5896 goto out_put;
5897
5898 error = unlock_lock(ls, lkb, &args);
5899
5900 if (error == -DLM_EUNLOCK)
5901 error = 0;
ef0c2bb0
DT		 5902 /* from validate_unlock_args() */
5903 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5904 error = 0;
597d0cae
DT		 5905 if (error)
5906 goto out_put;
5907
5908 spin_lock(&ua->proc->locks_spin);
23e8e1aa 5909 /* dlm_user_add_cb() may have already taken lkb off the proc list */
a1bc86e6
DT		 5910 if (!list_empty(&lkb->lkb_ownqueue))
5911 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 5912 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 5913 out_put:
5914 dlm_put_lkb(lkb);
5915 out:
85e86edf 5916 dlm_unlock_recovery(ls);
ef0c2bb0 5917 kfree(ua_tmp);
597d0cae
DT		 5918 return error;
5919}
5920
5921int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5922 uint32_t flags, uint32_t lkid)
5923{
5924 struct dlm_lkb *lkb;
5925 struct dlm_args args;
5926 struct dlm_user_args *ua;
5927 int error;
5928
85e86edf 5929 dlm_lock_recovery(ls);
597d0cae
DT		 5930
5931 error = find_lkb(ls, lkid, &lkb);
5932 if (error)
5933 goto out;
5934
d292c0cc 5935 ua = lkb->lkb_ua;
b434eda6
PC		 5936 if (ua_tmp->castparam)
5937 ua->castparam = ua_tmp->castparam;
c059f70e 5938 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 5939
5940 error = set_unlock_args(flags, ua, &args);
5941 if (error)
5942 goto out_put;
5943
5944 error = cancel_lock(ls, lkb, &args);
5945
5946 if (error == -DLM_ECANCEL)
5947 error = 0;
ef0c2bb0
DT		 5948 /* from validate_unlock_args() */
5949 if (error == -EBUSY)
5950 error = 0;
597d0cae
DT		 5951 out_put:
5952 dlm_put_lkb(lkb);
5953 out:
85e86edf 5954 dlm_unlock_recovery(ls);
ef0c2bb0 5955 kfree(ua_tmp);
597d0cae
DT		 5956 return error;
5957}
5958
8b4021fa
DT		 5959int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
5960{
5961 struct dlm_lkb *lkb;
5962 struct dlm_args args;
5963 struct dlm_user_args *ua;
5964 struct dlm_rsb *r;
5965 int error;
5966
5967 dlm_lock_recovery(ls);
5968
5969 error = find_lkb(ls, lkid, &lkb);
5970 if (error)
5971 goto out;
5972
d292c0cc 5973 ua = lkb->lkb_ua;
8b4021fa
DT		 5974
5975 error = set_unlock_args(flags, ua, &args);
5976 if (error)
5977 goto out_put;
5978
5979 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
5980
5981 r = lkb->lkb_resource;
5982 hold_rsb(r);
5983 lock_rsb(r);
5984
5985 error = validate_unlock_args(lkb, &args);
5986 if (error)
5987 goto out_r;
5988 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
5989
5990 error = _cancel_lock(r, lkb);
5991 out_r:
5992 unlock_rsb(r);
5993 put_rsb(r);
5994
5995 if (error == -DLM_ECANCEL)
5996 error = 0;
5997 /* from validate_unlock_args() */
5998 if (error == -EBUSY)
5999 error = 0;
6000 out_put:
6001 dlm_put_lkb(lkb);
6002 out:
6003 dlm_unlock_recovery(ls);
6004 return error;
6005}
6006
ef0c2bb0
DT		 6007/* lkb's that are removed from the waiters list by revert are just left on the
6008 orphans list with the granted orphan locks, to be freed by purge */
6009
597d0cae
DT		 6010static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6011{
ef0c2bb0
DT		 6012 struct dlm_args args;
6013 int error;
597d0cae 6014
ef0c2bb0
DT		 6015 hold_lkb(lkb);
6016 mutex_lock(&ls->ls_orphans_mutex);
6017 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
6018 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 6019
d292c0cc 6020 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 6021
6022 error = cancel_lock(ls, lkb, &args);
6023 if (error == -DLM_ECANCEL)
6024 error = 0;
6025 return error;
597d0cae
DT		 6026}
6027
6028/* The force flag allows the unlock to go ahead even if the lkb isn't granted.
6029 Regardless of what rsb queue the lock is on, it's removed and freed. */
6030
6031static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6032{
597d0cae
DT		 6033 struct dlm_args args;
6034 int error;
6035
d292c0cc 6036 set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
597d0cae
DT		 6037
6038 error = unlock_lock(ls, lkb, &args);
6039 if (error == -DLM_EUNLOCK)
6040 error = 0;
6041 return error;
6042}
6043
ef0c2bb0
DT		 6044/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
6045 (which does lock_rsb) due to deadlock with receiving a message that does
23e8e1aa 6046 lock_rsb followed by dlm_user_add_cb() */
ef0c2bb0
DT		 6047
6048static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
6049 struct dlm_user_proc *proc)
6050{
6051 struct dlm_lkb *lkb = NULL;
6052
6053 mutex_lock(&ls->ls_clear_proc_locks);
6054 if (list_empty(&proc->locks))
6055 goto out;
6056
6057 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
6058 list_del_init(&lkb->lkb_ownqueue);
6059
6060 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6061 lkb->lkb_flags |= DLM_IFL_ORPHAN;
6062 else
6063 lkb->lkb_flags |= DLM_IFL_DEAD;
6064 out:
6065 mutex_unlock(&ls->ls_clear_proc_locks);
6066 return lkb;
6067}
6068
23e8e1aa 6069/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
597d0cae
DT		 6070 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
6071 which we clear here. */
6072
6073/* proc CLOSING flag is set so no more device_reads should look at proc->asts
6074 list, and no more device_writes should add lkb's to proc->locks list; so we
6075 shouldn't need to take asts_spin or locks_spin here. this assumes that
6076 device reads/writes/closes are serialized -- FIXME: we may need to serialize
6077 them ourself. */
6078
6079void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6080{
6081 struct dlm_lkb *lkb, *safe;
6082
85e86edf 6083 dlm_lock_recovery(ls);
597d0cae 6084
ef0c2bb0
DT		 6085 while (1) {
6086 lkb = del_proc_lock(ls, proc);
6087 if (!lkb)
6088 break;
84d8cd69 6089 del_timeout(lkb);
ef0c2bb0 6090 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 6091 orphan_proc_lock(ls, lkb);
ef0c2bb0 6092 else
597d0cae 6093 unlock_proc_lock(ls, lkb);
597d0cae
DT		 6094
6095 /* this removes the reference for the proc->locks list
6096 added by dlm_user_request, it may result in the lkb
6097 being freed */
6098
6099 dlm_put_lkb(lkb);
6100 }
a1bc86e6 6101
ef0c2bb0
DT		 6102 mutex_lock(&ls->ls_clear_proc_locks);
6103
a1bc86e6
DT		 6104 /* in-progress unlocks */
6105 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6106 list_del_init(&lkb->lkb_ownqueue);
6107 lkb->lkb_flags |= DLM_IFL_DEAD;
6108 dlm_put_lkb(lkb);
6109 }
6110
23e8e1aa 6111 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6112 memset(&lkb->lkb_callbacks, 0,
6113 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6114 list_del_init(&lkb->lkb_cb_list);
a1bc86e6
DT		 6115 dlm_put_lkb(lkb);
6116 }
6117
597d0cae 6118 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 6119 dlm_unlock_recovery(ls);
597d0cae 6120}
a1bc86e6 6121
8499137d
DT		 6122static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6123{
6124 struct dlm_lkb *lkb, *safe;
6125
6126 while (1) {
6127 lkb = NULL;
6128 spin_lock(&proc->locks_spin);
6129 if (!list_empty(&proc->locks)) {
6130 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6131 lkb_ownqueue);
6132 list_del_init(&lkb->lkb_ownqueue);
6133 }
6134 spin_unlock(&proc->locks_spin);
6135
6136 if (!lkb)
6137 break;
6138
6139 lkb->lkb_flags |= DLM_IFL_DEAD;
6140 unlock_proc_lock(ls, lkb);
6141 dlm_put_lkb(lkb); /* ref from proc->locks list */
6142 }
6143
6144 spin_lock(&proc->locks_spin);
6145 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6146 list_del_init(&lkb->lkb_ownqueue);
6147 lkb->lkb_flags |= DLM_IFL_DEAD;
6148 dlm_put_lkb(lkb);
6149 }
6150 spin_unlock(&proc->locks_spin);
6151
6152 spin_lock(&proc->asts_spin);
23e8e1aa 6153 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6154 memset(&lkb->lkb_callbacks, 0,
6155 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6156 list_del_init(&lkb->lkb_cb_list);
8499137d
DT		 6157 dlm_put_lkb(lkb);
6158 }
6159 spin_unlock(&proc->asts_spin);
6160}
6161
6162/* pid of 0 means purge all orphans */
6163
6164static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6165{
6166 struct dlm_lkb *lkb, *safe;
6167
6168 mutex_lock(&ls->ls_orphans_mutex);
6169 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6170 if (pid && lkb->lkb_ownpid != pid)
6171 continue;
6172 unlock_proc_lock(ls, lkb);
6173 list_del_init(&lkb->lkb_ownqueue);
6174 dlm_put_lkb(lkb);
6175 }
6176 mutex_unlock(&ls->ls_orphans_mutex);
6177}
6178
6179static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6180{
6181 struct dlm_message *ms;
6182 struct dlm_mhandle *mh;
6183 int error;
6184
6185 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6186 DLM_MSG_PURGE, &ms, &mh);
6187 if (error)
6188 return error;
6189 ms->m_nodeid = nodeid;
6190 ms->m_pid = pid;
6191
6192 return send_message(mh, ms);
6193}
6194
6195int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6196 int nodeid, int pid)
6197{
6198 int error = 0;
6199
6200 if (nodeid != dlm_our_nodeid()) {
6201 error = send_purge(ls, nodeid, pid);
6202 } else {
85e86edf 6203 dlm_lock_recovery(ls);
8499137d
DT		 6204 if (pid == current->pid)
6205 purge_proc_locks(ls, proc);
6206 else
6207 do_purge(ls, nodeid, pid);
85e86edf 6208 dlm_unlock_recovery(ls);
8499137d
DT		 6209 }
6210 return error;
6211}
6212
Linux kernel - Deliverables
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