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dlm: prevent connections during shutdown
[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);
e7fd4179
DT		 93
94/*
95 * Lock compatibilty matrix - thanks Steve
96 * UN = Unlocked state. Not really a state, used as a flag
97 * PD = Padding. Used to make the matrix a nice power of two in size
98 * Other states are the same as the VMS DLM.
99 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
100 */
101
102static const int __dlm_compat_matrix[8][8] = {
103 /* UN NL CR CW PR PW EX PD */
104 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
105 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
106 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
107 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
108 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
109 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
110 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
111 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
112};
113
114/*
115 * This defines the direction of transfer of LVB data.
116 * Granted mode is the row; requested mode is the column.
117 * Usage: matrix[grmode+1][rqmode+1]
118 * 1 = LVB is returned to the caller
119 * 0 = LVB is written to the resource
120 * -1 = nothing happens to the LVB
121 */
122
123const int dlm_lvb_operations[8][8] = {
124 /* UN NL CR CW PR PW EX PD*/
125 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
126 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
127 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
128 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
129 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
130 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
131 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
132 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
133};
e7fd4179
DT		 134
135#define modes_compat(gr, rq) \
136 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
137
138int dlm_modes_compat(int mode1, int mode2)
139{
140 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
141}
142
143/*
144 * Compatibility matrix for conversions with QUECVT set.
145 * Granted mode is the row; requested mode is the column.
146 * Usage: matrix[grmode+1][rqmode+1]
147 */
148
149static const int __quecvt_compat_matrix[8][8] = {
150 /* UN NL CR CW PR PW EX PD */
151 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
152 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
153 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
154 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
155 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
156 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
157 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
158 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
159};
160
597d0cae 161void dlm_print_lkb(struct dlm_lkb *lkb)
e7fd4179
DT		 162{
163 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n"
8304d6f2 164 " status %d rqmode %d grmode %d wait_type %d\n",
e7fd4179
DT		 165 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
166 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
8304d6f2 167 lkb->lkb_grmode, lkb->lkb_wait_type);
e7fd4179
DT		 168}
169
170e19ab 170static void dlm_print_rsb(struct dlm_rsb *r)
e7fd4179
DT		 171{
172 printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n",
173 r->res_nodeid, r->res_flags, r->res_first_lkid,
174 r->res_recover_locks_count, r->res_name);
175}
176
a345da3e
DT		 177void dlm_dump_rsb(struct dlm_rsb *r)
178{
179 struct dlm_lkb *lkb;
180
181 dlm_print_rsb(r);
182
183 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
184 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
185 printk(KERN_ERR "rsb lookup list\n");
186 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
187 dlm_print_lkb(lkb);
188 printk(KERN_ERR "rsb grant queue:\n");
189 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
190 dlm_print_lkb(lkb);
191 printk(KERN_ERR "rsb convert queue:\n");
192 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
193 dlm_print_lkb(lkb);
194 printk(KERN_ERR "rsb wait queue:\n");
195 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
196 dlm_print_lkb(lkb);
197}
198
e7fd4179
DT		 199/* Threads cannot use the lockspace while it's being recovered */
200
85e86edf 201static inline void dlm_lock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 202{
203 down_read(&ls->ls_in_recovery);
204}
205
85e86edf 206void dlm_unlock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 207{
208 up_read(&ls->ls_in_recovery);
209}
210
85e86edf 211int dlm_lock_recovery_try(struct dlm_ls *ls)
e7fd4179
DT		 212{
213 return down_read_trylock(&ls->ls_in_recovery);
214}
215
216static inline int can_be_queued(struct dlm_lkb *lkb)
217{
218 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
219}
220
221static inline int force_blocking_asts(struct dlm_lkb *lkb)
222{
223 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
224}
225
226static inline int is_demoted(struct dlm_lkb *lkb)
227{
228 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
229}
230
7d3c1feb
DT		 231static inline int is_altmode(struct dlm_lkb *lkb)
232{
233 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
234}
235
236static inline int is_granted(struct dlm_lkb *lkb)
237{
238 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
239}
240
e7fd4179
DT		 241static inline int is_remote(struct dlm_rsb *r)
242{
243 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
244 return !!r->res_nodeid;
245}
246
247static inline int is_process_copy(struct dlm_lkb *lkb)
248{
249 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
250}
251
252static inline int is_master_copy(struct dlm_lkb *lkb)
253{
254 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
255 DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb););
90135925 256 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
e7fd4179
DT		 257}
258
259static inline int middle_conversion(struct dlm_lkb *lkb)
260{
261 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
262 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
90135925
DT		 263 return 1;
264 return 0;
e7fd4179
DT		 265}
266
267static inline int down_conversion(struct dlm_lkb *lkb)
268{
269 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
270}
271
ef0c2bb0
DT		 272static inline int is_overlap_unlock(struct dlm_lkb *lkb)
273{
274 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
275}
276
277static inline int is_overlap_cancel(struct dlm_lkb *lkb)
278{
279 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
280}
281
282static inline int is_overlap(struct dlm_lkb *lkb)
283{
284 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
285 DLM_IFL_OVERLAP_CANCEL));
286}
287
e7fd4179
DT		 288static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
289{
290 if (is_master_copy(lkb))
291 return;
292
3ae1acf9
DT		 293 del_timeout(lkb);
294
e7fd4179
DT		 295 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
296
3ae1acf9
DT		 297 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
298 timeout caused the cancel then return -ETIMEDOUT */
299 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
300 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
301 rv = -ETIMEDOUT;
302 }
303
8b4021fa
DT		 304 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
305 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
306 rv = -EDEADLK;
307 }
308
23e8e1aa 309 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
e7fd4179
DT		 310}
311
ef0c2bb0
DT		 312static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
313{
314 queue_cast(r, lkb,
315 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
316}
317
e7fd4179
DT		 318static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
319{
b6fa8796 320 if (is_master_copy(lkb)) {
e7fd4179 321 send_bast(r, lkb, rqmode);
b6fa8796 322 } else {
23e8e1aa 323 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
b6fa8796 324 }
e7fd4179
DT		 325}
326
327/*
328 * Basic operations on rsb's and lkb's
329 */
330
3881ac04
DT		 331static int pre_rsb_struct(struct dlm_ls *ls)
332{
333 struct dlm_rsb *r1, *r2;
334 int count = 0;
335
336 spin_lock(&ls->ls_new_rsb_spin);
337 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
338 spin_unlock(&ls->ls_new_rsb_spin);
339 return 0;
340 }
341 spin_unlock(&ls->ls_new_rsb_spin);
342
343 r1 = dlm_allocate_rsb(ls);
344 r2 = dlm_allocate_rsb(ls);
345
346 spin_lock(&ls->ls_new_rsb_spin);
347 if (r1) {
348 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
349 ls->ls_new_rsb_count++;
350 }
351 if (r2) {
352 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
353 ls->ls_new_rsb_count++;
354 }
355 count = ls->ls_new_rsb_count;
356 spin_unlock(&ls->ls_new_rsb_spin);
357
358 if (!count)
359 return -ENOMEM;
360 return 0;
361}
362
363/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
364 unlock any spinlocks, go back and call pre_rsb_struct again.
365 Otherwise, take an rsb off the list and return it. */
366
367static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
368 struct dlm_rsb **r_ret)
e7fd4179
DT		 369{
370 struct dlm_rsb *r;
3881ac04
DT		 371 int count;
372
373 spin_lock(&ls->ls_new_rsb_spin);
374 if (list_empty(&ls->ls_new_rsb)) {
375 count = ls->ls_new_rsb_count;
376 spin_unlock(&ls->ls_new_rsb_spin);
377 log_debug(ls, "find_rsb retry %d %d %s",
378 count, dlm_config.ci_new_rsb_count, name);
379 return -EAGAIN;
380 }
e7fd4179 381
3881ac04
DT		 382 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
383 list_del(&r->res_hashchain);
9beb3bf5
BP		 384 /* Convert the empty list_head to a NULL rb_node for tree usage: */
385 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
3881ac04
DT		 386 ls->ls_new_rsb_count--;
387 spin_unlock(&ls->ls_new_rsb_spin);
e7fd4179
DT		 388
389 r->res_ls = ls;
390 r->res_length = len;
391 memcpy(r->res_name, name, len);
90135925 392 mutex_init(&r->res_mutex);
e7fd4179
DT		 393
394 INIT_LIST_HEAD(&r->res_lookup);
395 INIT_LIST_HEAD(&r->res_grantqueue);
396 INIT_LIST_HEAD(&r->res_convertqueue);
397 INIT_LIST_HEAD(&r->res_waitqueue);
398 INIT_LIST_HEAD(&r->res_root_list);
399 INIT_LIST_HEAD(&r->res_recover_list);
400
3881ac04
DT		 401 *r_ret = r;
402 return 0;
e7fd4179
DT		 403}
404
9beb3bf5
BP		 405static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
406{
407 char maxname[DLM_RESNAME_MAXLEN];
408
409 memset(maxname, 0, DLM_RESNAME_MAXLEN);
410 memcpy(maxname, name, nlen);
411 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
412}
413
7210cb7a
DT		 414int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
415 unsigned int flags, struct dlm_rsb **r_ret)
e7fd4179 416{
9beb3bf5 417 struct rb_node *node = tree->rb_node;
e7fd4179
DT		 418 struct dlm_rsb *r;
419 int error = 0;
9beb3bf5
BP		 420 int rc;
421
422 while (node) {
423 r = rb_entry(node, struct dlm_rsb, res_hashnode);
424 rc = rsb_cmp(r, name, len);
425 if (rc < 0)
426 node = node->rb_left;
427 else if (rc > 0)
428 node = node->rb_right;
429 else
e7fd4179
DT		 430 goto found;
431 }
18c60c0a 432 *r_ret = NULL;
597d0cae 433 return -EBADR;
e7fd4179
DT		 434
435 found:
436 if (r->res_nodeid && (flags & R_MASTER))
437 error = -ENOTBLK;
438 *r_ret = r;
439 return error;
440}
441
9beb3bf5
BP		 442static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
443{
444 struct rb_node **newn = &tree->rb_node;
445 struct rb_node *parent = NULL;
446 int rc;
447
448 while (*newn) {
449 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
450 res_hashnode);
451
452 parent = *newn;
453 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
454 if (rc < 0)
455 newn = &parent->rb_left;
456 else if (rc > 0)
457 newn = &parent->rb_right;
458 else {
459 log_print("rsb_insert match");
460 dlm_dump_rsb(rsb);
461 dlm_dump_rsb(cur);
462 return -EEXIST;
463 }
464 }
465
466 rb_link_node(&rsb->res_hashnode, parent, newn);
467 rb_insert_color(&rsb->res_hashnode, tree);
468 return 0;
469}
470
e7fd4179
DT		 471static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b,
472 unsigned int flags, struct dlm_rsb **r_ret)
473{
474 struct dlm_rsb *r;
475 int error;
476
7210cb7a 477 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, flags, &r);
e7fd4179
DT		 478 if (!error) {
479 kref_get(&r->res_ref);
480 goto out;
481 }
7210cb7a 482 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
e7fd4179
DT		 483 if (error)
484 goto out;
485
9beb3bf5
BP		 486 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
487 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
488 if (error)
489 return error;
e7fd4179
DT		 490
491 if (dlm_no_directory(ls))
492 goto out;
493
494 if (r->res_nodeid == -1) {
495 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
496 r->res_first_lkid = 0;
497 } else if (r->res_nodeid > 0) {
498 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
499 r->res_first_lkid = 0;
500 } else {
501 DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r););
502 DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),);
503 }
504 out:
505 *r_ret = r;
506 return error;
507}
508
e7fd4179
DT		 509/*
510 * Find rsb in rsbtbl and potentially create/add one
511 *
512 * Delaying the release of rsb's has a similar benefit to applications keeping
513 * NL locks on an rsb, but without the guarantee that the cached master value
514 * will still be valid when the rsb is reused. Apps aren't always smart enough
515 * to keep NL locks on an rsb that they may lock again shortly; this can lead
516 * to excessive master lookups and removals if we don't delay the release.
517 *
518 * Searching for an rsb means looking through both the normal list and toss
519 * list. When found on the toss list the rsb is moved to the normal list with
520 * ref count of 1; when found on normal list the ref count is incremented.
521 */
522
523static int find_rsb(struct dlm_ls *ls, char *name, int namelen,
524 unsigned int flags, struct dlm_rsb **r_ret)
525{
3881ac04 526 struct dlm_rsb *r = NULL;
e7fd4179 527 uint32_t hash, bucket;
3881ac04 528 int error;
ef58bcca 529
3881ac04
DT		 530 if (namelen > DLM_RESNAME_MAXLEN) {
531 error = -EINVAL;
ef58bcca 532 goto out;
3881ac04 533 }
e7fd4179
DT		 534
535 if (dlm_no_directory(ls))
536 flags |= R_CREATE;
537
538 hash = jhash(name, namelen, 0);
539 bucket = hash & (ls->ls_rsbtbl_size - 1);
540
3881ac04
DT		 541 retry:
542 if (flags & R_CREATE) {
543 error = pre_rsb_struct(ls);
544 if (error < 0)
545 goto out;
546 }
547
548 spin_lock(&ls->ls_rsbtbl[bucket].lock);
549
550 error = _search_rsb(ls, name, namelen, bucket, flags, &r);
e7fd4179 551 if (!error)
3881ac04 552 goto out_unlock;
e7fd4179 553
597d0cae 554 if (error == -EBADR && !(flags & R_CREATE))
3881ac04 555 goto out_unlock;
e7fd4179
DT		 556
557 /* the rsb was found but wasn't a master copy */
558 if (error == -ENOTBLK)
3881ac04 559 goto out_unlock;
e7fd4179 560
3881ac04
DT		 561 error = get_rsb_struct(ls, name, namelen, &r);
562 if (error == -EAGAIN) {
563 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
564 goto retry;
565 }
566 if (error)
567 goto out_unlock;
e7fd4179
DT		 568
569 r->res_hash = hash;
570 r->res_bucket = bucket;
571 r->res_nodeid = -1;
572 kref_init(&r->res_ref);
573
574 /* With no directory, the master can be set immediately */
575 if (dlm_no_directory(ls)) {
576 int nodeid = dlm_dir_nodeid(r);
577 if (nodeid == dlm_our_nodeid())
578 nodeid = 0;
579 r->res_nodeid = nodeid;
580 }
9beb3bf5 581 error = rsb_insert(r, &ls->ls_rsbtbl[bucket].keep);
3881ac04
DT		 582 out_unlock:
583 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179
DT		 584 out:
585 *r_ret = r;
586 return error;
587}
588
e7fd4179
DT		 589/* This is only called to add a reference when the code already holds
590 a valid reference to the rsb, so there's no need for locking. */
591
592static inline void hold_rsb(struct dlm_rsb *r)
593{
594 kref_get(&r->res_ref);
595}
596
597void dlm_hold_rsb(struct dlm_rsb *r)
598{
599 hold_rsb(r);
600}
601
602static void toss_rsb(struct kref *kref)
603{
604 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
605 struct dlm_ls *ls = r->res_ls;
606
607 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
608 kref_init(&r->res_ref);
9beb3bf5
BP		 609 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
610 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
e7fd4179
DT		 611 r->res_toss_time = jiffies;
612 if (r->res_lvbptr) {
52bda2b5 613 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 614 r->res_lvbptr = NULL;
615 }
616}
617
25985edc 618/* When all references to the rsb are gone it's transferred to
e7fd4179
DT		 619 the tossed list for later disposal. */
620
621static void put_rsb(struct dlm_rsb *r)
622{
623 struct dlm_ls *ls = r->res_ls;
624 uint32_t bucket = r->res_bucket;
625
c7be761a 626 spin_lock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179 627 kref_put(&r->res_ref, toss_rsb);
c7be761a 628 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
e7fd4179
DT		 629}
630
631void dlm_put_rsb(struct dlm_rsb *r)
632{
633 put_rsb(r);
634}
635
636/* See comment for unhold_lkb */
637
638static void unhold_rsb(struct dlm_rsb *r)
639{
640 int rv;
641 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 642 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 643}
644
645static void kill_rsb(struct kref *kref)
646{
647 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
648
649 /* All work is done after the return from kref_put() so we
650 can release the write_lock before the remove and free. */
651
a345da3e
DT		 652 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
653 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
654 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
655 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
656 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
657 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 658}
659
660/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
661 The rsb must exist as long as any lkb's for it do. */
662
663static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
664{
665 hold_rsb(r);
666 lkb->lkb_resource = r;
667}
668
669static void detach_lkb(struct dlm_lkb *lkb)
670{
671 if (lkb->lkb_resource) {
672 put_rsb(lkb->lkb_resource);
673 lkb->lkb_resource = NULL;
674 }
675}
676
677static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
678{
3d6aa675
DT		 679 struct dlm_lkb *lkb;
680 int rv, id;
e7fd4179 681
52bda2b5 682 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 683 if (!lkb)
684 return -ENOMEM;
685
686 lkb->lkb_nodeid = -1;
687 lkb->lkb_grmode = DLM_LOCK_IV;
688 kref_init(&lkb->lkb_ref);
34e22bed 689 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 690 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 691 INIT_LIST_HEAD(&lkb->lkb_time_list);
23e8e1aa
DT		 692 INIT_LIST_HEAD(&lkb->lkb_cb_list);
693 mutex_init(&lkb->lkb_cb_mutex);
694 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
e7fd4179 695
3d6aa675
DT		 696 retry:
697 rv = idr_pre_get(&ls->ls_lkbidr, GFP_NOFS);
698 if (!rv)
699 return -ENOMEM;
e7fd4179 700
3d6aa675
DT		 701 spin_lock(&ls->ls_lkbidr_spin);
702 rv = idr_get_new_above(&ls->ls_lkbidr, lkb, 1, &id);
703 if (!rv)
704 lkb->lkb_id = id;
705 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179 706
3d6aa675
DT		 707 if (rv == -EAGAIN)
708 goto retry;
e7fd4179 709
3d6aa675
DT		 710 if (rv < 0) {
711 log_error(ls, "create_lkb idr error %d", rv);
712 return rv;
e7fd4179
DT		 713 }
714
e7fd4179
DT		 715 *lkb_ret = lkb;
716 return 0;
717}
718
e7fd4179
DT		 719static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
720{
721 struct dlm_lkb *lkb;
e7fd4179 722
3d6aa675
DT		 723 spin_lock(&ls->ls_lkbidr_spin);
724 lkb = idr_find(&ls->ls_lkbidr, lkid);
e7fd4179
DT		 725 if (lkb)
726 kref_get(&lkb->lkb_ref);
3d6aa675 727 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 728
729 *lkb_ret = lkb;
730 return lkb ? 0 : -ENOENT;
731}
732
733static void kill_lkb(struct kref *kref)
734{
735 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
736
737 /* All work is done after the return from kref_put() so we
738 can release the write_lock before the detach_lkb */
739
740 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
741}
742
b3f58d8f
DT		 743/* __put_lkb() is used when an lkb may not have an rsb attached to
744 it so we need to provide the lockspace explicitly */
745
746static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 747{
3d6aa675 748 uint32_t lkid = lkb->lkb_id;
e7fd4179 749
3d6aa675 750 spin_lock(&ls->ls_lkbidr_spin);
e7fd4179 751 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
3d6aa675
DT		 752 idr_remove(&ls->ls_lkbidr, lkid);
753 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 754
755 detach_lkb(lkb);
756
757 /* for local/process lkbs, lvbptr points to caller's lksb */
758 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 759 dlm_free_lvb(lkb->lkb_lvbptr);
760 dlm_free_lkb(lkb);
e7fd4179
DT		 761 return 1;
762 } else {
3d6aa675 763 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 764 return 0;
765 }
766}
767
768int dlm_put_lkb(struct dlm_lkb *lkb)
769{
b3f58d8f
DT		 770 struct dlm_ls *ls;
771
772 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
773 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
774
775 ls = lkb->lkb_resource->res_ls;
776 return __put_lkb(ls, lkb);
e7fd4179
DT		 777}
778
779/* This is only called to add a reference when the code already holds
780 a valid reference to the lkb, so there's no need for locking. */
781
782static inline void hold_lkb(struct dlm_lkb *lkb)
783{
784 kref_get(&lkb->lkb_ref);
785}
786
787/* This is called when we need to remove a reference and are certain
788 it's not the last ref. e.g. del_lkb is always called between a
789 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
790 put_lkb would work fine, but would involve unnecessary locking */
791
792static inline void unhold_lkb(struct dlm_lkb *lkb)
793{
794 int rv;
795 rv = kref_put(&lkb->lkb_ref, kill_lkb);
796 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
797}
798
799static void lkb_add_ordered(struct list_head *new, struct list_head *head,
800 int mode)
801{
802 struct dlm_lkb *lkb = NULL;
803
804 list_for_each_entry(lkb, head, lkb_statequeue)
805 if (lkb->lkb_rqmode < mode)
806 break;
807
99fb19d4 808 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
e7fd4179
DT		 809}
810
811/* add/remove lkb to rsb's grant/convert/wait queue */
812
813static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
814{
815 kref_get(&lkb->lkb_ref);
816
817 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
818
eeda418d
DT		 819 lkb->lkb_timestamp = ktime_get();
820
e7fd4179
DT		 821 lkb->lkb_status = status;
822
823 switch (status) {
824 case DLM_LKSTS_WAITING:
825 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
826 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
827 else
828 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
829 break;
830 case DLM_LKSTS_GRANTED:
831 /* convention says granted locks kept in order of grmode */
832 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
833 lkb->lkb_grmode);
834 break;
835 case DLM_LKSTS_CONVERT:
836 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
837 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
838 else
839 list_add_tail(&lkb->lkb_statequeue,
840 &r->res_convertqueue);
841 break;
842 default:
843 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
844 }
845}
846
847static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
848{
849 lkb->lkb_status = 0;
850 list_del(&lkb->lkb_statequeue);
851 unhold_lkb(lkb);
852}
853
854static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
855{
856 hold_lkb(lkb);
857 del_lkb(r, lkb);
858 add_lkb(r, lkb, sts);
859 unhold_lkb(lkb);
860}
861
ef0c2bb0
DT		 862static int msg_reply_type(int mstype)
863{
864 switch (mstype) {
865 case DLM_MSG_REQUEST:
866 return DLM_MSG_REQUEST_REPLY;
867 case DLM_MSG_CONVERT:
868 return DLM_MSG_CONVERT_REPLY;
869 case DLM_MSG_UNLOCK:
870 return DLM_MSG_UNLOCK_REPLY;
871 case DLM_MSG_CANCEL:
872 return DLM_MSG_CANCEL_REPLY;
873 case DLM_MSG_LOOKUP:
874 return DLM_MSG_LOOKUP_REPLY;
875 }
876 return -1;
877}
878
c6ff669b
DT		 879static int nodeid_warned(int nodeid, int num_nodes, int *warned)
880{
881 int i;
882
883 for (i = 0; i < num_nodes; i++) {
884 if (!warned[i]) {
885 warned[i] = nodeid;
886 return 0;
887 }
888 if (warned[i] == nodeid)
889 return 1;
890 }
891 return 0;
892}
893
894void dlm_scan_waiters(struct dlm_ls *ls)
895{
896 struct dlm_lkb *lkb;
897 ktime_t zero = ktime_set(0, 0);
898 s64 us;
899 s64 debug_maxus = 0;
900 u32 debug_scanned = 0;
901 u32 debug_expired = 0;
902 int num_nodes = 0;
903 int *warned = NULL;
904
905 if (!dlm_config.ci_waitwarn_us)
906 return;
907
908 mutex_lock(&ls->ls_waiters_mutex);
909
910 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
911 if (ktime_equal(lkb->lkb_wait_time, zero))
912 continue;
913
914 debug_scanned++;
915
916 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
917
918 if (us < dlm_config.ci_waitwarn_us)
919 continue;
920
921 lkb->lkb_wait_time = zero;
922
923 debug_expired++;
924 if (us > debug_maxus)
925 debug_maxus = us;
926
927 if (!num_nodes) {
928 num_nodes = ls->ls_num_nodes;
5d70828a 929 warned = kzalloc(num_nodes * sizeof(int), GFP_KERNEL);
c6ff669b
DT		 930 }
931 if (!warned)
932 continue;
933 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
934 continue;
935
936 log_error(ls, "waitwarn %x %lld %d us check connection to "
937 "node %d", lkb->lkb_id, (long long)us,
938 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
939 }
940 mutex_unlock(&ls->ls_waiters_mutex);
5d70828a 941 kfree(warned);
c6ff669b
DT		 942
943 if (debug_expired)
944 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
945 debug_scanned, debug_expired,
946 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
947}
948
e7fd4179
DT		 949/* add/remove lkb from global waiters list of lkb's waiting for
950 a reply from a remote node */
951
c6ff669b 952static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
e7fd4179
DT		 953{
954 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 955 int error = 0;
e7fd4179 956
90135925 957 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 958
959 if (is_overlap_unlock(lkb) ||
960 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
961 error = -EINVAL;
962 goto out;
963 }
964
965 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
966 switch (mstype) {
967 case DLM_MSG_UNLOCK:
968 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
969 break;
970 case DLM_MSG_CANCEL:
971 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
972 break;
973 default:
974 error = -EBUSY;
975 goto out;
976 }
977 lkb->lkb_wait_count++;
978 hold_lkb(lkb);
979
43279e53 980 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
ef0c2bb0
DT		 981 lkb->lkb_id, lkb->lkb_wait_type, mstype,
982 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 983 goto out;
984 }
ef0c2bb0
DT		 985
986 DLM_ASSERT(!lkb->lkb_wait_count,
987 dlm_print_lkb(lkb);
988 printk("wait_count %d\n", lkb->lkb_wait_count););
989
990 lkb->lkb_wait_count++;
e7fd4179 991 lkb->lkb_wait_type = mstype;
c6ff669b
DT		 992 lkb->lkb_wait_time = ktime_get();
993 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
ef0c2bb0 994 hold_lkb(lkb);
e7fd4179
DT		 995 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
996 out:
ef0c2bb0 997 if (error)
43279e53 998 log_error(ls, "addwait error %x %d flags %x %d %d %s",
ef0c2bb0
DT		 999 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1000 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 1001 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 1002 return error;
e7fd4179
DT		 1003}
1004
b790c3b7
DT		 1005/* We clear the RESEND flag because we might be taking an lkb off the waiters
1006 list as part of process_requestqueue (e.g. a lookup that has an optimized
1007 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1008 set RESEND and dlm_recover_waiters_post() */
1009
43279e53
DT		 1010static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1011 struct dlm_message *ms)
e7fd4179 1012{
ef0c2bb0
DT		 1013 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1014 int overlap_done = 0;
e7fd4179 1015
ef0c2bb0 1016 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
43279e53 1017 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1018 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1019 overlap_done = 1;
1020 goto out_del;
e7fd4179 1021 }
ef0c2bb0
DT		 1022
1023 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
43279e53 1024 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1025 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1026 overlap_done = 1;
1027 goto out_del;
1028 }
1029
43279e53
DT		 1030 /* Cancel state was preemptively cleared by a successful convert,
1031 see next comment, nothing to do. */
1032
1033 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1034 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1035 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1036 lkb->lkb_id, lkb->lkb_wait_type);
1037 return -1;
1038 }
1039
1040 /* Remove for the convert reply, and premptively remove for the
1041 cancel reply. A convert has been granted while there's still
1042 an outstanding cancel on it (the cancel is moot and the result
1043 in the cancel reply should be 0). We preempt the cancel reply
1044 because the app gets the convert result and then can follow up
1045 with another op, like convert. This subsequent op would see the
1046 lingering state of the cancel and fail with -EBUSY. */
1047
1048 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1049 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1050 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1051 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1052 lkb->lkb_id);
1053 lkb->lkb_wait_type = 0;
1054 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1055 lkb->lkb_wait_count--;
1056 goto out_del;
1057 }
1058
ef0c2bb0
DT		 1059 /* N.B. type of reply may not always correspond to type of original
1060 msg due to lookup->request optimization, verify others? */
1061
1062 if (lkb->lkb_wait_type) {
1063 lkb->lkb_wait_type = 0;
1064 goto out_del;
1065 }
1066
43279e53
DT		 1067 log_error(ls, "remwait error %x reply %d flags %x no wait_type",
1068 lkb->lkb_id, mstype, lkb->lkb_flags);
ef0c2bb0
DT		 1069 return -1;
1070
1071 out_del:
1072 /* the force-unlock/cancel has completed and we haven't recvd a reply
1073 to the op that was in progress prior to the unlock/cancel; we
1074 give up on any reply to the earlier op. FIXME: not sure when/how
1075 this would happen */
1076
1077 if (overlap_done && lkb->lkb_wait_type) {
43279e53 1078 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
ef0c2bb0
DT		 1079 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1080 lkb->lkb_wait_count--;
1081 lkb->lkb_wait_type = 0;
1082 }
1083
1084 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1085
b790c3b7 1086 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 1087 lkb->lkb_wait_count--;
1088 if (!lkb->lkb_wait_count)
1089 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 1090 unhold_lkb(lkb);
ef0c2bb0 1091 return 0;
e7fd4179
DT		 1092}
1093
ef0c2bb0 1094static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 1095{
1096 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1097 int error;
1098
90135925 1099 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1100 error = _remove_from_waiters(lkb, mstype, NULL);
90135925 1101 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 1102 return error;
1103}
1104
ef0c2bb0
DT		 1105/* Handles situations where we might be processing a "fake" or "stub" reply in
1106 which we can't try to take waiters_mutex again. */
1107
1108static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1109{
1110 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1111 int error;
1112
2a7ce0ed 1113 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0 1114 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1115 error = _remove_from_waiters(lkb, ms->m_type, ms);
2a7ce0ed 1116 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0
DT		 1117 mutex_unlock(&ls->ls_waiters_mutex);
1118 return error;
1119}
1120
e7fd4179
DT		 1121static void dir_remove(struct dlm_rsb *r)
1122{
1123 int to_nodeid;
1124
1125 if (dlm_no_directory(r->res_ls))
1126 return;
1127
1128 to_nodeid = dlm_dir_nodeid(r);
1129 if (to_nodeid != dlm_our_nodeid())
1130 send_remove(r);
1131 else
1132 dlm_dir_remove_entry(r->res_ls, to_nodeid,
1133 r->res_name, r->res_length);
1134}
1135
9beb3bf5 1136/* FIXME: make this more efficient */
e7fd4179
DT		 1137
1138static int shrink_bucket(struct dlm_ls *ls, int b)
1139{
9beb3bf5 1140 struct rb_node *n;
e7fd4179
DT		 1141 struct dlm_rsb *r;
1142 int count = 0, found;
1143
1144 for (;;) {
90135925 1145 found = 0;
c7be761a 1146 spin_lock(&ls->ls_rsbtbl[b].lock);
9beb3bf5
BP		 1147 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = rb_next(n)) {
1148 r = rb_entry(n, struct dlm_rsb, res_hashnode);
e7fd4179 1149 if (!time_after_eq(jiffies, r->res_toss_time +
68c817a1 1150 dlm_config.ci_toss_secs * HZ))
e7fd4179 1151 continue;
90135925 1152 found = 1;
e7fd4179
DT		 1153 break;
1154 }
1155
1156 if (!found) {
c7be761a 1157 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1158 break;
1159 }
1160
1161 if (kref_put(&r->res_ref, kill_rsb)) {
9beb3bf5 1162 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
c7be761a 1163 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1164
1165 if (is_master(r))
1166 dir_remove(r);
52bda2b5 1167 dlm_free_rsb(r);
e7fd4179
DT		 1168 count++;
1169 } else {
c7be761a 1170 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1171 log_error(ls, "tossed rsb in use %s", r->res_name);
1172 }
1173 }
1174
1175 return count;
1176}
1177
1178void dlm_scan_rsbs(struct dlm_ls *ls)
1179{
1180 int i;
1181
e7fd4179
DT		 1182 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1183 shrink_bucket(ls, i);
85e86edf
DT		 1184 if (dlm_locking_stopped(ls))
1185 break;
e7fd4179
DT		 1186 cond_resched();
1187 }
1188}
1189
3ae1acf9
DT		 1190static void add_timeout(struct dlm_lkb *lkb)
1191{
1192 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1193
eeda418d 1194 if (is_master_copy(lkb))
3ae1acf9 1195 return;
3ae1acf9
DT		 1196
1197 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1198 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1199 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1200 goto add_it;
1201 }
84d8cd69
DT		 1202 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1203 goto add_it;
3ae1acf9
DT		 1204 return;
1205
1206 add_it:
1207 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1208 mutex_lock(&ls->ls_timeout_mutex);
1209 hold_lkb(lkb);
3ae1acf9
DT		 1210 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1211 mutex_unlock(&ls->ls_timeout_mutex);
1212}
1213
1214static void del_timeout(struct dlm_lkb *lkb)
1215{
1216 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1217
1218 mutex_lock(&ls->ls_timeout_mutex);
1219 if (!list_empty(&lkb->lkb_time_list)) {
1220 list_del_init(&lkb->lkb_time_list);
1221 unhold_lkb(lkb);
1222 }
1223 mutex_unlock(&ls->ls_timeout_mutex);
1224}
1225
1226/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1227 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1228 and then lock rsb because of lock ordering in add_timeout. We may need
1229 to specify some special timeout-related bits in the lkb that are just to
1230 be accessed under the timeout_mutex. */
1231
1232void dlm_scan_timeout(struct dlm_ls *ls)
1233{
1234 struct dlm_rsb *r;
1235 struct dlm_lkb *lkb;
1236 int do_cancel, do_warn;
eeda418d 1237 s64 wait_us;
3ae1acf9
DT		 1238
1239 for (;;) {
1240 if (dlm_locking_stopped(ls))
1241 break;
1242
1243 do_cancel = 0;
1244 do_warn = 0;
1245 mutex_lock(&ls->ls_timeout_mutex);
1246 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1247
eeda418d
DT		 1248 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1249 lkb->lkb_timestamp));
1250
3ae1acf9 1251 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
eeda418d 1252 wait_us >= (lkb->lkb_timeout_cs * 10000))
3ae1acf9
DT		 1253 do_cancel = 1;
1254
1255 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
eeda418d 1256 wait_us >= dlm_config.ci_timewarn_cs * 10000)
3ae1acf9
DT		 1257 do_warn = 1;
1258
1259 if (!do_cancel && !do_warn)
1260 continue;
1261 hold_lkb(lkb);
1262 break;
1263 }
1264 mutex_unlock(&ls->ls_timeout_mutex);
1265
1266 if (!do_cancel && !do_warn)
1267 break;
1268
1269 r = lkb->lkb_resource;
1270 hold_rsb(r);
1271 lock_rsb(r);
1272
1273 if (do_warn) {
1274 /* clear flag so we only warn once */
1275 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1276 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1277 del_timeout(lkb);
1278 dlm_timeout_warn(lkb);
1279 }
1280
1281 if (do_cancel) {
b3cab7b9 1282 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1283 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1284 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1285 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1286 del_timeout(lkb);
1287 _cancel_lock(r, lkb);
1288 }
1289
1290 unlock_rsb(r);
1291 unhold_rsb(r);
1292 dlm_put_lkb(lkb);
1293 }
1294}
1295
1296/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1297 dlm_recoverd before checking/setting ls_recover_begin. */
1298
1299void dlm_adjust_timeouts(struct dlm_ls *ls)
1300{
1301 struct dlm_lkb *lkb;
eeda418d 1302 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
3ae1acf9
DT		 1303
1304 ls->ls_recover_begin = 0;
1305 mutex_lock(&ls->ls_timeout_mutex);
1306 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
eeda418d 1307 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
3ae1acf9 1308 mutex_unlock(&ls->ls_timeout_mutex);
c6ff669b
DT		 1309
1310 if (!dlm_config.ci_waitwarn_us)
1311 return;
1312
1313 mutex_lock(&ls->ls_waiters_mutex);
1314 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1315 if (ktime_to_us(lkb->lkb_wait_time))
1316 lkb->lkb_wait_time = ktime_get();
1317 }
1318 mutex_unlock(&ls->ls_waiters_mutex);
3ae1acf9
DT		 1319}
1320
e7fd4179
DT		 1321/* lkb is master or local copy */
1322
1323static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1324{
1325 int b, len = r->res_ls->ls_lvblen;
1326
1327 /* b=1 lvb returned to caller
1328 b=0 lvb written to rsb or invalidated
1329 b=-1 do nothing */
1330
1331 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1332
1333 if (b == 1) {
1334 if (!lkb->lkb_lvbptr)
1335 return;
1336
1337 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1338 return;
1339
1340 if (!r->res_lvbptr)
1341 return;
1342
1343 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1344 lkb->lkb_lvbseq = r->res_lvbseq;
1345
1346 } else if (b == 0) {
1347 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1348 rsb_set_flag(r, RSB_VALNOTVALID);
1349 return;
1350 }
1351
1352 if (!lkb->lkb_lvbptr)
1353 return;
1354
1355 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1356 return;
1357
1358 if (!r->res_lvbptr)
52bda2b5 1359 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1360
1361 if (!r->res_lvbptr)
1362 return;
1363
1364 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1365 r->res_lvbseq++;
1366 lkb->lkb_lvbseq = r->res_lvbseq;
1367 rsb_clear_flag(r, RSB_VALNOTVALID);
1368 }
1369
1370 if (rsb_flag(r, RSB_VALNOTVALID))
1371 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1372}
1373
1374static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1375{
1376 if (lkb->lkb_grmode < DLM_LOCK_PW)
1377 return;
1378
1379 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1380 rsb_set_flag(r, RSB_VALNOTVALID);
1381 return;
1382 }
1383
1384 if (!lkb->lkb_lvbptr)
1385 return;
1386
1387 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1388 return;
1389
1390 if (!r->res_lvbptr)
52bda2b5 1391 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1392
1393 if (!r->res_lvbptr)
1394 return;
1395
1396 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
1397 r->res_lvbseq++;
1398 rsb_clear_flag(r, RSB_VALNOTVALID);
1399}
1400
1401/* lkb is process copy (pc) */
1402
1403static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1404 struct dlm_message *ms)
1405{
1406 int b;
1407
1408 if (!lkb->lkb_lvbptr)
1409 return;
1410
1411 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1412 return;
1413
597d0cae 1414 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 1415 if (b == 1) {
1416 int len = receive_extralen(ms);
a9cc9159
AV		 1417 if (len > DLM_RESNAME_MAXLEN)
1418 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 1419 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
1420 lkb->lkb_lvbseq = ms->m_lvbseq;
1421 }
1422}
1423
1424/* Manipulate lkb's on rsb's convert/granted/waiting queues
1425 remove_lock -- used for unlock, removes lkb from granted
1426 revert_lock -- used for cancel, moves lkb from convert to granted
1427 grant_lock -- used for request and convert, adds lkb to granted or
1428 moves lkb from convert or waiting to granted
1429
1430 Each of these is used for master or local copy lkb's. There is
1431 also a _pc() variation used to make the corresponding change on
1432 a process copy (pc) lkb. */
1433
1434static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1435{
1436 del_lkb(r, lkb);
1437 lkb->lkb_grmode = DLM_LOCK_IV;
1438 /* this unhold undoes the original ref from create_lkb()
1439 so this leads to the lkb being freed */
1440 unhold_lkb(lkb);
1441}
1442
1443static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1444{
1445 set_lvb_unlock(r, lkb);
1446 _remove_lock(r, lkb);
1447}
1448
1449static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
1450{
1451 _remove_lock(r, lkb);
1452}
1453
ef0c2bb0
DT		 1454/* returns: 0 did nothing
1455 1 moved lock to granted
1456 -1 removed lock */
1457
1458static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1459{
ef0c2bb0
DT		 1460 int rv = 0;
1461
e7fd4179
DT		 1462 lkb->lkb_rqmode = DLM_LOCK_IV;
1463
1464 switch (lkb->lkb_status) {
597d0cae
DT		 1465 case DLM_LKSTS_GRANTED:
1466 break;
e7fd4179
DT		 1467 case DLM_LKSTS_CONVERT:
1468 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 1469 rv = 1;
e7fd4179
DT		 1470 break;
1471 case DLM_LKSTS_WAITING:
1472 del_lkb(r, lkb);
1473 lkb->lkb_grmode = DLM_LOCK_IV;
1474 /* this unhold undoes the original ref from create_lkb()
1475 so this leads to the lkb being freed */
1476 unhold_lkb(lkb);
ef0c2bb0 1477 rv = -1;
e7fd4179
DT		 1478 break;
1479 default:
1480 log_print("invalid status for revert %d", lkb->lkb_status);
1481 }
ef0c2bb0 1482 return rv;
e7fd4179
DT		 1483}
1484
ef0c2bb0 1485static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 1486{
ef0c2bb0 1487 return revert_lock(r, lkb);
e7fd4179
DT		 1488}
1489
1490static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1491{
1492 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
1493 lkb->lkb_grmode = lkb->lkb_rqmode;
1494 if (lkb->lkb_status)
1495 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
1496 else
1497 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
1498 }
1499
1500 lkb->lkb_rqmode = DLM_LOCK_IV;
e7fd4179
DT		 1501}
1502
1503static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1504{
1505 set_lvb_lock(r, lkb);
1506 _grant_lock(r, lkb);
1507 lkb->lkb_highbast = 0;
1508}
1509
1510static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
1511 struct dlm_message *ms)
1512{
1513 set_lvb_lock_pc(r, lkb, ms);
1514 _grant_lock(r, lkb);
1515}
1516
1517/* called by grant_pending_locks() which means an async grant message must
1518 be sent to the requesting node in addition to granting the lock if the
1519 lkb belongs to a remote node. */
1520
1521static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
1522{
1523 grant_lock(r, lkb);
1524 if (is_master_copy(lkb))
1525 send_grant(r, lkb);
1526 else
1527 queue_cast(r, lkb, 0);
1528}
1529
7d3c1feb
DT		 1530/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
1531 change the granted/requested modes. We're munging things accordingly in
1532 the process copy.
1533 CONVDEADLK: our grmode may have been forced down to NL to resolve a
1534 conversion deadlock
1535 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
1536 compatible with other granted locks */
1537
2a7ce0ed 1538static void munge_demoted(struct dlm_lkb *lkb)
7d3c1feb 1539{
7d3c1feb
DT		 1540 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
1541 log_print("munge_demoted %x invalid modes gr %d rq %d",
1542 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
1543 return;
1544 }
1545
1546 lkb->lkb_grmode = DLM_LOCK_NL;
1547}
1548
1549static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
1550{
1551 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
1552 ms->m_type != DLM_MSG_GRANT) {
1553 log_print("munge_altmode %x invalid reply type %d",
1554 lkb->lkb_id, ms->m_type);
1555 return;
1556 }
1557
1558 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
1559 lkb->lkb_rqmode = DLM_LOCK_PR;
1560 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
1561 lkb->lkb_rqmode = DLM_LOCK_CW;
1562 else {
1563 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
1564 dlm_print_lkb(lkb);
1565 }
1566}
1567
e7fd4179
DT		 1568static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
1569{
1570 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
1571 lkb_statequeue);
1572 if (lkb->lkb_id == first->lkb_id)
90135925 1573 return 1;
e7fd4179 1574
90135925 1575 return 0;
e7fd4179
DT		 1576}
1577
e7fd4179
DT		 1578/* Check if the given lkb conflicts with another lkb on the queue. */
1579
1580static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
1581{
1582 struct dlm_lkb *this;
1583
1584 list_for_each_entry(this, head, lkb_statequeue) {
1585 if (this == lkb)
1586 continue;
3bcd3687 1587 if (!modes_compat(this, lkb))
90135925 1588 return 1;
e7fd4179 1589 }
90135925 1590 return 0;
e7fd4179
DT		 1591}
1592
1593/*
1594 * "A conversion deadlock arises with a pair of lock requests in the converting
1595 * queue for one resource. The granted mode of each lock blocks the requested
1596 * mode of the other lock."
1597 *
c85d65e9
DT		 1598 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
1599 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 1600 *
1601 * Example:
1602 * Granted Queue: empty
1603 * Convert Queue: NL->EX (first lock)
1604 * PR->EX (second lock)
1605 *
1606 * The first lock can't be granted because of the granted mode of the second
1607 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 1608 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
1609 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
1610 * flag set and return DEMOTED in the lksb flags.
e7fd4179 1611 *
c85d65e9
DT		 1612 * Originally, this function detected conv-deadlk in a more limited scope:
1613 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
1614 * - if lkb1 was the first entry in the queue (not just earlier), and was
1615 * blocked by the granted mode of lkb2, and there was nothing on the
1616 * granted queue preventing lkb1 from being granted immediately, i.e.
1617 * lkb2 was the only thing preventing lkb1 from being granted.
1618 *
1619 * That second condition meant we'd only say there was conv-deadlk if
1620 * resolving it (by demotion) would lead to the first lock on the convert
1621 * queue being granted right away. It allowed conversion deadlocks to exist
1622 * between locks on the convert queue while they couldn't be granted anyway.
1623 *
1624 * Now, we detect and take action on conversion deadlocks immediately when
1625 * they're created, even if they may not be immediately consequential. If
1626 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
1627 * mode that would prevent lkb1's conversion from being granted, we do a
1628 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
1629 * I think this means that the lkb_is_ahead condition below should always
1630 * be zero, i.e. there will never be conv-deadlk between two locks that are
1631 * both already on the convert queue.
e7fd4179
DT		 1632 */
1633
c85d65e9 1634static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 1635{
c85d65e9
DT		 1636 struct dlm_lkb *lkb1;
1637 int lkb_is_ahead = 0;
e7fd4179 1638
c85d65e9
DT		 1639 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
1640 if (lkb1 == lkb2) {
1641 lkb_is_ahead = 1;
e7fd4179
DT		 1642 continue;
1643 }
1644
c85d65e9
DT		 1645 if (!lkb_is_ahead) {
1646 if (!modes_compat(lkb2, lkb1))
1647 return 1;
1648 } else {
1649 if (!modes_compat(lkb2, lkb1) &&
1650 !modes_compat(lkb1, lkb2))
1651 return 1;
1652 }
e7fd4179 1653 }
90135925 1654 return 0;
e7fd4179
DT		 1655}
1656
1657/*
1658 * Return 1 if the lock can be granted, 0 otherwise.
1659 * Also detect and resolve conversion deadlocks.
1660 *
1661 * lkb is the lock to be granted
1662 *
1663 * now is 1 if the function is being called in the context of the
1664 * immediate request, it is 0 if called later, after the lock has been
1665 * queued.
1666 *
1667 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
1668 */
1669
1670static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now)
1671{
1672 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
1673
1674 /*
1675 * 6-10: Version 5.4 introduced an option to address the phenomenon of
1676 * a new request for a NL mode lock being blocked.
1677 *
1678 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
1679 * request, then it would be granted. In essence, the use of this flag
1680 * tells the Lock Manager to expedite theis request by not considering
1681 * what may be in the CONVERTING or WAITING queues... As of this
1682 * writing, the EXPEDITE flag can be used only with new requests for NL
1683 * mode locks. This flag is not valid for conversion requests.
1684 *
1685 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
1686 * conversion or used with a non-NL requested mode. We also know an
1687 * EXPEDITE request is always granted immediately, so now must always
1688 * be 1. The full condition to grant an expedite request: (now &&
1689 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
1690 * therefore be shortened to just checking the flag.
1691 */
1692
1693 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 1694 return 1;
e7fd4179
DT		 1695
1696 /*
1697 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
1698 * added to the remaining conditions.
1699 */
1700
1701 if (queue_conflict(&r->res_grantqueue, lkb))
1702 goto out;
1703
1704 /*
1705 * 6-3: By default, a conversion request is immediately granted if the
1706 * requested mode is compatible with the modes of all other granted
1707 * locks
1708 */
1709
1710 if (queue_conflict(&r->res_convertqueue, lkb))
1711 goto out;
1712
1713 /*
1714 * 6-5: But the default algorithm for deciding whether to grant or
1715 * queue conversion requests does not by itself guarantee that such
1716 * requests are serviced on a "first come first serve" basis. This, in
1717 * turn, can lead to a phenomenon known as "indefinate postponement".
1718 *
1719 * 6-7: This issue is dealt with by using the optional QUECVT flag with
1720 * the system service employed to request a lock conversion. This flag
1721 * forces certain conversion requests to be queued, even if they are
1722 * compatible with the granted modes of other locks on the same
1723 * resource. Thus, the use of this flag results in conversion requests
1724 * being ordered on a "first come first servce" basis.
1725 *
1726 * DCT: This condition is all about new conversions being able to occur
1727 * "in place" while the lock remains on the granted queue (assuming
1728 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
1729 * doesn't _have_ to go onto the convert queue where it's processed in
1730 * order. The "now" variable is necessary to distinguish converts
1731 * being received and processed for the first time now, because once a
1732 * convert is moved to the conversion queue the condition below applies
1733 * requiring fifo granting.
1734 */
1735
1736 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 1737 return 1;
e7fd4179 1738
53ad1c98
DT		 1739 /*
1740 * Even if the convert is compat with all granted locks,
1741 * QUECVT forces it behind other locks on the convert queue.
1742 */
1743
1744 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
1745 if (list_empty(&r->res_convertqueue))
1746 return 1;
1747 else
1748 goto out;
1749 }
1750
e7fd4179 1751 /*
3bcd3687
DT		 1752 * The NOORDER flag is set to avoid the standard vms rules on grant
1753 * order.
e7fd4179
DT		 1754 */
1755
1756 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 1757 return 1;
e7fd4179
DT		 1758
1759 /*
1760 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
1761 * granted until all other conversion requests ahead of it are granted
1762 * and/or canceled.
1763 */
1764
1765 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 1766 return 1;
e7fd4179
DT		 1767
1768 /*
1769 * 6-4: By default, a new request is immediately granted only if all
1770 * three of the following conditions are satisfied when the request is
1771 * issued:
1772 * - The queue of ungranted conversion requests for the resource is
1773 * empty.
1774 * - The queue of ungranted new requests for the resource is empty.
1775 * - The mode of the new request is compatible with the most
1776 * restrictive mode of all granted locks on the resource.
1777 */
1778
1779 if (now && !conv && list_empty(&r->res_convertqueue) &&
1780 list_empty(&r->res_waitqueue))
90135925 1781 return 1;
e7fd4179
DT		 1782
1783 /*
1784 * 6-4: Once a lock request is in the queue of ungranted new requests,
1785 * it cannot be granted until the queue of ungranted conversion
1786 * requests is empty, all ungranted new requests ahead of it are
1787 * granted and/or canceled, and it is compatible with the granted mode
1788 * of the most restrictive lock granted on the resource.
1789 */
1790
1791 if (!now && !conv && list_empty(&r->res_convertqueue) &&
1792 first_in_list(lkb, &r->res_waitqueue))
90135925 1793 return 1;
e7fd4179 1794 out:
90135925 1795 return 0;
e7fd4179
DT		 1796}
1797
c85d65e9
DT		 1798static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
1799 int *err)
e7fd4179 1800{
e7fd4179
DT		 1801 int rv;
1802 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 1803 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
1804
1805 if (err)
1806 *err = 0;
e7fd4179
DT		 1807
1808 rv = _can_be_granted(r, lkb, now);
1809 if (rv)
1810 goto out;
1811
c85d65e9
DT		 1812 /*
1813 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
1814 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
1815 * cancels one of the locks.
1816 */
1817
1818 if (is_convert && can_be_queued(lkb) &&
1819 conversion_deadlock_detect(r, lkb)) {
1820 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
1821 lkb->lkb_grmode = DLM_LOCK_NL;
1822 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
1823 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1824 if (err)
1825 *err = -EDEADLK;
1826 else {
1827 log_print("can_be_granted deadlock %x now %d",
1828 lkb->lkb_id, now);
1829 dlm_dump_rsb(r);
1830 }
1831 }
e7fd4179 1832 goto out;
c85d65e9 1833 }
e7fd4179 1834
c85d65e9
DT		 1835 /*
1836 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
1837 * to grant a request in a mode other than the normal rqmode. It's a
1838 * simple way to provide a big optimization to applications that can
1839 * use them.
1840 */
1841
1842 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 1843 alt = DLM_LOCK_PR;
c85d65e9 1844 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 1845 alt = DLM_LOCK_CW;
1846
1847 if (alt) {
1848 lkb->lkb_rqmode = alt;
1849 rv = _can_be_granted(r, lkb, now);
1850 if (rv)
1851 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
1852 else
1853 lkb->lkb_rqmode = rqmode;
1854 }
1855 out:
1856 return rv;
1857}
1858
c85d65e9
DT		 1859/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
1860 for locks pending on the convert list. Once verified (watch for these
1861 log_prints), we should be able to just call _can_be_granted() and not
1862 bother with the demote/deadlk cases here (and there's no easy way to deal
1863 with a deadlk here, we'd have to generate something like grant_lock with
1864 the deadlk error.) */
1865
36509258
DT		 1866/* Returns the highest requested mode of all blocked conversions; sets
1867 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 1868
36509258 1869static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1870{
1871 struct dlm_lkb *lkb, *s;
1872 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 1873 int deadlk;
e7fd4179
DT		 1874
1875 quit = 0;
1876 restart:
1877 grant_restart = 0;
1878 demote_restart = 0;
1879 hi = DLM_LOCK_IV;
1880
1881 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
1882 demoted = is_demoted(lkb);
c85d65e9
DT		 1883 deadlk = 0;
1884
1885 if (can_be_granted(r, lkb, 0, &deadlk)) {
e7fd4179
DT		 1886 grant_lock_pending(r, lkb);
1887 grant_restart = 1;
c85d65e9 1888 continue;
e7fd4179 1889 }
c85d65e9
DT		 1890
1891 if (!demoted && is_demoted(lkb)) {
1892 log_print("WARN: pending demoted %x node %d %s",
1893 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1894 demote_restart = 1;
1895 continue;
1896 }
1897
1898 if (deadlk) {
1899 log_print("WARN: pending deadlock %x node %d %s",
1900 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
1901 dlm_dump_rsb(r);
1902 continue;
1903 }
1904
1905 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 1906
1907 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
1908 *cw = 1;
e7fd4179
DT		 1909 }
1910
1911 if (grant_restart)
1912 goto restart;
1913 if (demote_restart && !quit) {
1914 quit = 1;
1915 goto restart;
1916 }
1917
1918 return max_t(int, high, hi);
1919}
1920
36509258 1921static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw)
e7fd4179
DT		 1922{
1923 struct dlm_lkb *lkb, *s;
1924
1925 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c85d65e9 1926 if (can_be_granted(r, lkb, 0, NULL))
e7fd4179 1927 grant_lock_pending(r, lkb);
36509258 1928 else {
e7fd4179 1929 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 1930 if (lkb->lkb_rqmode == DLM_LOCK_CW)
1931 *cw = 1;
1932 }
e7fd4179
DT		 1933 }
1934
1935 return high;
1936}
1937
36509258
DT		 1938/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
1939 on either the convert or waiting queue.
1940 high is the largest rqmode of all locks blocked on the convert or
1941 waiting queue. */
1942
1943static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
1944{
1945 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
1946 if (gr->lkb_highbast < DLM_LOCK_EX)
1947 return 1;
1948 return 0;
1949 }
1950
1951 if (gr->lkb_highbast < high &&
1952 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
1953 return 1;
1954 return 0;
1955}
1956
e7fd4179
DT		 1957static void grant_pending_locks(struct dlm_rsb *r)
1958{
1959 struct dlm_lkb *lkb, *s;
1960 int high = DLM_LOCK_IV;
36509258 1961 int cw = 0;
e7fd4179 1962
a345da3e 1963 DLM_ASSERT(is_master(r), dlm_dump_rsb(r););
e7fd4179 1964
36509258
DT		 1965 high = grant_pending_convert(r, high, &cw);
1966 high = grant_pending_wait(r, high, &cw);
e7fd4179
DT		 1967
1968 if (high == DLM_LOCK_IV)
1969 return;
1970
1971 /*
1972 * If there are locks left on the wait/convert queue then send blocking
1973 * ASTs to granted locks based on the largest requested mode (high)
36509258 1974 * found above.
e7fd4179
DT		 1975 */
1976
1977 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 1978 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
329fc4c3
DT		 1979 if (cw && high == DLM_LOCK_PR &&
1980 lkb->lkb_grmode == DLM_LOCK_PR)
36509258
DT		 1981 queue_bast(r, lkb, DLM_LOCK_CW);
1982 else
1983 queue_bast(r, lkb, high);
e7fd4179
DT		 1984 lkb->lkb_highbast = high;
1985 }
1986 }
1987}
1988
36509258
DT		 1989static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
1990{
1991 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
1992 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
1993 if (gr->lkb_highbast < DLM_LOCK_EX)
1994 return 1;
1995 return 0;
1996 }
1997
1998 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
1999 return 1;
2000 return 0;
2001}
2002
e7fd4179
DT		 2003static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2004 struct dlm_lkb *lkb)
2005{
2006 struct dlm_lkb *gr;
2007
2008 list_for_each_entry(gr, head, lkb_statequeue) {
314dd2a0
SW		 2009 /* skip self when sending basts to convertqueue */
2010 if (gr == lkb)
2011 continue;
e5dae548 2012 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 2013 queue_bast(r, gr, lkb->lkb_rqmode);
2014 gr->lkb_highbast = lkb->lkb_rqmode;
2015 }
2016 }
2017}
2018
2019static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2020{
2021 send_bast_queue(r, &r->res_grantqueue, lkb);
2022}
2023
2024static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2025{
2026 send_bast_queue(r, &r->res_grantqueue, lkb);
2027 send_bast_queue(r, &r->res_convertqueue, lkb);
2028}
2029
2030/* set_master(r, lkb) -- set the master nodeid of a resource
2031
2032 The purpose of this function is to set the nodeid field in the given
2033 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2034 known, it can just be copied to the lkb and the function will return
2035 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2036 before it can be copied to the lkb.
2037
2038 When the rsb nodeid is being looked up remotely, the initial lkb
2039 causing the lookup is kept on the ls_waiters list waiting for the
2040 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2041 on the rsb's res_lookup list until the master is verified.
2042
2043 Return values:
2044 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2045 1: the rsb master is not available and the lkb has been placed on
2046 a wait queue
2047*/
2048
2049static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2050{
2051 struct dlm_ls *ls = r->res_ls;
755b5eb8 2052 int i, error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 2053
2054 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2055 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2056 r->res_first_lkid = lkb->lkb_id;
2057 lkb->lkb_nodeid = r->res_nodeid;
2058 return 0;
2059 }
2060
2061 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2062 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2063 return 1;
2064 }
2065
2066 if (r->res_nodeid == 0) {
2067 lkb->lkb_nodeid = 0;
2068 return 0;
2069 }
2070
2071 if (r->res_nodeid > 0) {
2072 lkb->lkb_nodeid = r->res_nodeid;
2073 return 0;
2074 }
2075
a345da3e 2076 DLM_ASSERT(r->res_nodeid == -1, dlm_dump_rsb(r););
e7fd4179
DT		 2077
2078 dir_nodeid = dlm_dir_nodeid(r);
2079
2080 if (dir_nodeid != our_nodeid) {
2081 r->res_first_lkid = lkb->lkb_id;
2082 send_lookup(r, lkb);
2083 return 1;
2084 }
2085
755b5eb8 2086 for (i = 0; i < 2; i++) {
e7fd4179
DT		 2087 /* It's possible for dlm_scand to remove an old rsb for
2088 this same resource from the toss list, us to create
2089 a new one, look up the master locally, and find it
2090 already exists just before dlm_scand does the
2091 dir_remove() on the previous rsb. */
2092
2093 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
2094 r->res_length, &ret_nodeid);
2095 if (!error)
2096 break;
2097 log_debug(ls, "dir_lookup error %d %s", error, r->res_name);
2098 schedule();
2099 }
755b5eb8
DT		 2100 if (error && error != -EEXIST)
2101 return error;
e7fd4179
DT		 2102
2103 if (ret_nodeid == our_nodeid) {
2104 r->res_first_lkid = 0;
2105 r->res_nodeid = 0;
2106 lkb->lkb_nodeid = 0;
2107 } else {
2108 r->res_first_lkid = lkb->lkb_id;
2109 r->res_nodeid = ret_nodeid;
2110 lkb->lkb_nodeid = ret_nodeid;
2111 }
2112 return 0;
2113}
2114
2115static void process_lookup_list(struct dlm_rsb *r)
2116{
2117 struct dlm_lkb *lkb, *safe;
2118
2119 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 2120 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2121 _request_lock(r, lkb);
2122 schedule();
2123 }
2124}
2125
2126/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2127
2128static void confirm_master(struct dlm_rsb *r, int error)
2129{
2130 struct dlm_lkb *lkb;
2131
2132 if (!r->res_first_lkid)
2133 return;
2134
2135 switch (error) {
2136 case 0:
2137 case -EINPROGRESS:
2138 r->res_first_lkid = 0;
2139 process_lookup_list(r);
2140 break;
2141
2142 case -EAGAIN:
aec64e1b
DT		 2143 case -EBADR:
2144 case -ENOTBLK:
2145 /* the remote request failed and won't be retried (it was
2146 a NOQUEUE, or has been canceled/unlocked); make a waiting
2147 lkb the first_lkid */
e7fd4179
DT		 2148
2149 r->res_first_lkid = 0;
2150
2151 if (!list_empty(&r->res_lookup)) {
2152 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2153 lkb_rsb_lookup);
ef0c2bb0 2154 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2155 r->res_first_lkid = lkb->lkb_id;
2156 _request_lock(r, lkb);
761b9d3f 2157 }
e7fd4179
DT		 2158 break;
2159
2160 default:
2161 log_error(r->res_ls, "confirm_master unknown error %d", error);
2162 }
2163}
2164
2165static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 2166 int namelen, unsigned long timeout_cs,
2167 void (*ast) (void *astparam),
2168 void *astparam,
2169 void (*bast) (void *astparam, int mode),
2170 struct dlm_args *args)
e7fd4179
DT		 2171{
2172 int rv = -EINVAL;
2173
2174 /* check for invalid arg usage */
2175
2176 if (mode < 0 || mode > DLM_LOCK_EX)
2177 goto out;
2178
2179 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2180 goto out;
2181
2182 if (flags & DLM_LKF_CANCEL)
2183 goto out;
2184
2185 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2186 goto out;
2187
2188 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2189 goto out;
2190
2191 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2192 goto out;
2193
2194 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2195 goto out;
2196
2197 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2198 goto out;
2199
2200 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2201 goto out;
2202
2203 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2204 goto out;
2205
2206 if (!ast || !lksb)
2207 goto out;
2208
2209 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2210 goto out;
2211
e7fd4179
DT		 2212 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2213 goto out;
2214
2215 /* these args will be copied to the lkb in validate_lock_args,
2216 it cannot be done now because when converting locks, fields in
2217 an active lkb cannot be modified before locking the rsb */
2218
2219 args->flags = flags;
e5dae548
DT		 2220 args->astfn = ast;
2221 args->astparam = astparam;
2222 args->bastfn = bast;
d7db923e 2223 args->timeout = timeout_cs;
e7fd4179
DT		 2224 args->mode = mode;
2225 args->lksb = lksb;
e7fd4179
DT		 2226 rv = 0;
2227 out:
2228 return rv;
2229}
2230
2231static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2232{
2233 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2234 DLM_LKF_FORCEUNLOCK))
2235 return -EINVAL;
2236
ef0c2bb0
DT		 2237 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2238 return -EINVAL;
2239
e7fd4179 2240 args->flags = flags;
e5dae548 2241 args->astparam = astarg;
e7fd4179
DT		 2242 return 0;
2243}
2244
2245static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2246 struct dlm_args *args)
2247{
2248 int rv = -EINVAL;
2249
2250 if (args->flags & DLM_LKF_CONVERT) {
2251 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2252 goto out;
2253
2254 if (args->flags & DLM_LKF_QUECVT &&
2255 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2256 goto out;
2257
2258 rv = -EBUSY;
2259 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2260 goto out;
2261
2262 if (lkb->lkb_wait_type)
2263 goto out;
ef0c2bb0
DT		 2264
2265 if (is_overlap(lkb))
2266 goto out;
e7fd4179
DT		 2267 }
2268
2269 lkb->lkb_exflags = args->flags;
2270 lkb->lkb_sbflags = 0;
e5dae548 2271 lkb->lkb_astfn = args->astfn;
e7fd4179 2272 lkb->lkb_astparam = args->astparam;
e5dae548 2273 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2274 lkb->lkb_rqmode = args->mode;
2275 lkb->lkb_lksb = args->lksb;
2276 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2277 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2278 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2279 rv = 0;
2280 out:
43279e53
DT		 2281 if (rv)
2282 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2283 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2284 lkb->lkb_status, lkb->lkb_wait_type,
2285 lkb->lkb_resource->res_name);
e7fd4179
DT		 2286 return rv;
2287}
2288
ef0c2bb0
DT		 2289/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2290 for success */
2291
2292/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2293 because there may be a lookup in progress and it's valid to do
2294 cancel/unlockf on it */
2295
e7fd4179
DT		 2296static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2297{
ef0c2bb0 2298 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2299 int rv = -EINVAL;
2300
ef0c2bb0
DT		 2301 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2302 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2303 dlm_print_lkb(lkb);
e7fd4179 2304 goto out;
ef0c2bb0 2305 }
e7fd4179 2306
ef0c2bb0
DT		 2307 /* an lkb may still exist even though the lock is EOL'ed due to a
2308 cancel, unlock or failed noqueue request; an app can't use these
2309 locks; return same error as if the lkid had not been found at all */
e7fd4179 2310
ef0c2bb0
DT		 2311 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2312 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2313 rv = -ENOENT;
e7fd4179 2314 goto out;
ef0c2bb0 2315 }
e7fd4179 2316
ef0c2bb0
DT		 2317 /* an lkb may be waiting for an rsb lookup to complete where the
2318 lookup was initiated by another lock */
2319
42dc1601
DT		 2320 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2321 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2322 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2323 list_del_init(&lkb->lkb_rsb_lookup);
2324 queue_cast(lkb->lkb_resource, lkb,
2325 args->flags & DLM_LKF_CANCEL ?
2326 -DLM_ECANCEL : -DLM_EUNLOCK);
2327 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2328 }
42dc1601
DT		 2329 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2330 rv = -EBUSY;
2331 goto out;
ef0c2bb0
DT		 2332 }
2333
2334 /* cancel not allowed with another cancel/unlock in progress */
2335
2336 if (args->flags & DLM_LKF_CANCEL) {
2337 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2338 goto out;
2339
2340 if (is_overlap(lkb))
2341 goto out;
2342
3ae1acf9
DT		 2343 /* don't let scand try to do a cancel */
2344 del_timeout(lkb);
2345
ef0c2bb0
DT		 2346 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2347 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2348 rv = -EBUSY;
2349 goto out;
2350 }
2351
a536e381
DT		 2352 /* there's nothing to cancel */
2353 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2354 !lkb->lkb_wait_type) {
2355 rv = -EBUSY;
2356 goto out;
2357 }
2358
ef0c2bb0
DT		 2359 switch (lkb->lkb_wait_type) {
2360 case DLM_MSG_LOOKUP:
2361 case DLM_MSG_REQUEST:
2362 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2363 rv = -EBUSY;
2364 goto out;
2365 case DLM_MSG_UNLOCK:
2366 case DLM_MSG_CANCEL:
2367 goto out;
2368 }
2369 /* add_to_waiters() will set OVERLAP_CANCEL */
2370 goto out_ok;
2371 }
2372
2373 /* do we need to allow a force-unlock if there's a normal unlock
2374 already in progress? in what conditions could the normal unlock
2375 fail such that we'd want to send a force-unlock to be sure? */
2376
2377 if (args->flags & DLM_LKF_FORCEUNLOCK) {
2378 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
2379 goto out;
2380
2381 if (is_overlap_unlock(lkb))
2382 goto out;
e7fd4179 2383
3ae1acf9
DT		 2384 /* don't let scand try to do a cancel */
2385 del_timeout(lkb);
2386
ef0c2bb0
DT		 2387 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2388 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2389 rv = -EBUSY;
2390 goto out;
2391 }
2392
2393 switch (lkb->lkb_wait_type) {
2394 case DLM_MSG_LOOKUP:
2395 case DLM_MSG_REQUEST:
2396 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
2397 rv = -EBUSY;
2398 goto out;
2399 case DLM_MSG_UNLOCK:
2400 goto out;
2401 }
2402 /* add_to_waiters() will set OVERLAP_UNLOCK */
2403 goto out_ok;
2404 }
2405
2406 /* normal unlock not allowed if there's any op in progress */
e7fd4179 2407 rv = -EBUSY;
ef0c2bb0 2408 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 2409 goto out;
2410
2411 out_ok:
ef0c2bb0
DT		 2412 /* an overlapping op shouldn't blow away exflags from other op */
2413 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 2414 lkb->lkb_sbflags = 0;
2415 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 2416 rv = 0;
2417 out:
ef0c2bb0
DT		 2418 if (rv)
2419 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
2420 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
2421 args->flags, lkb->lkb_wait_type,
2422 lkb->lkb_resource->res_name);
e7fd4179
DT		 2423 return rv;
2424}
2425
2426/*
2427 * Four stage 4 varieties:
2428 * do_request(), do_convert(), do_unlock(), do_cancel()
2429 * These are called on the master node for the given lock and
2430 * from the central locking logic.
2431 */
2432
2433static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
2434{
2435 int error = 0;
2436
c85d65e9 2437 if (can_be_granted(r, lkb, 1, NULL)) {
e7fd4179
DT		 2438 grant_lock(r, lkb);
2439 queue_cast(r, lkb, 0);
2440 goto out;
2441 }
2442
2443 if (can_be_queued(lkb)) {
2444 error = -EINPROGRESS;
2445 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9 2446 add_timeout(lkb);
e7fd4179
DT		 2447 goto out;
2448 }
2449
2450 error = -EAGAIN;
e7fd4179 2451 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 2452 out:
2453 return error;
2454}
2455
cf6620ac
DT		 2456static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2457 int error)
2458{
2459 switch (error) {
2460 case -EAGAIN:
2461 if (force_blocking_asts(lkb))
2462 send_blocking_asts_all(r, lkb);
2463 break;
2464 case -EINPROGRESS:
2465 send_blocking_asts(r, lkb);
2466 break;
2467 }
2468}
2469
e7fd4179
DT		 2470static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
2471{
2472 int error = 0;
c85d65e9 2473 int deadlk = 0;
e7fd4179
DT		 2474
2475 /* changing an existing lock may allow others to be granted */
2476
c85d65e9 2477 if (can_be_granted(r, lkb, 1, &deadlk)) {
e7fd4179
DT		 2478 grant_lock(r, lkb);
2479 queue_cast(r, lkb, 0);
e7fd4179
DT		 2480 goto out;
2481 }
2482
c85d65e9
DT		 2483 /* can_be_granted() detected that this lock would block in a conversion
2484 deadlock, so we leave it on the granted queue and return EDEADLK in
2485 the ast for the convert. */
2486
2487 if (deadlk) {
2488 /* it's left on the granted queue */
c85d65e9
DT		 2489 revert_lock(r, lkb);
2490 queue_cast(r, lkb, -EDEADLK);
2491 error = -EDEADLK;
2492 goto out;
2493 }
2494
7d3c1feb
DT		 2495 /* is_demoted() means the can_be_granted() above set the grmode
2496 to NL, and left us on the granted queue. This auto-demotion
2497 (due to CONVDEADLK) might mean other locks, and/or this lock, are
2498 now grantable. We have to try to grant other converting locks
2499 before we try again to grant this one. */
2500
2501 if (is_demoted(lkb)) {
36509258 2502 grant_pending_convert(r, DLM_LOCK_IV, NULL);
7d3c1feb
DT		 2503 if (_can_be_granted(r, lkb, 1)) {
2504 grant_lock(r, lkb);
2505 queue_cast(r, lkb, 0);
7d3c1feb
DT		 2506 goto out;
2507 }
2508 /* else fall through and move to convert queue */
2509 }
2510
2511 if (can_be_queued(lkb)) {
e7fd4179
DT		 2512 error = -EINPROGRESS;
2513 del_lkb(r, lkb);
2514 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 2515 add_timeout(lkb);
e7fd4179
DT		 2516 goto out;
2517 }
2518
2519 error = -EAGAIN;
e7fd4179 2520 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 2521 out:
2522 return error;
2523}
2524
cf6620ac
DT		 2525static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2526 int error)
2527{
2528 switch (error) {
2529 case 0:
2530 grant_pending_locks(r);
2531 /* grant_pending_locks also sends basts */
2532 break;
2533 case -EAGAIN:
2534 if (force_blocking_asts(lkb))
2535 send_blocking_asts_all(r, lkb);
2536 break;
2537 case -EINPROGRESS:
2538 send_blocking_asts(r, lkb);
2539 break;
2540 }
2541}
2542
e7fd4179
DT		 2543static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2544{
2545 remove_lock(r, lkb);
2546 queue_cast(r, lkb, -DLM_EUNLOCK);
e7fd4179
DT		 2547 return -DLM_EUNLOCK;
2548}
2549
cf6620ac
DT		 2550static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2551 int error)
2552{
2553 grant_pending_locks(r);
2554}
2555
ef0c2bb0 2556/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
907b9bce 2557
e7fd4179
DT		 2558static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
2559{
ef0c2bb0
DT		 2560 int error;
2561
2562 error = revert_lock(r, lkb);
2563 if (error) {
2564 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 2565 return -DLM_ECANCEL;
2566 }
2567 return 0;
e7fd4179
DT		 2568}
2569
cf6620ac
DT		 2570static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
2571 int error)
2572{
2573 if (error)
2574 grant_pending_locks(r);
2575}
2576
e7fd4179
DT		 2577/*
2578 * Four stage 3 varieties:
2579 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
2580 */
2581
2582/* add a new lkb to a possibly new rsb, called by requesting process */
2583
2584static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2585{
2586 int error;
2587
2588 /* set_master: sets lkb nodeid from r */
2589
2590 error = set_master(r, lkb);
2591 if (error < 0)
2592 goto out;
2593 if (error) {
2594 error = 0;
2595 goto out;
2596 }
2597
cf6620ac 2598 if (is_remote(r)) {
e7fd4179
DT		 2599 /* receive_request() calls do_request() on remote node */
2600 error = send_request(r, lkb);
cf6620ac 2601 } else {
e7fd4179 2602 error = do_request(r, lkb);
cf6620ac
DT		 2603 /* for remote locks the request_reply is sent
2604 between do_request and do_request_effects */
2605 do_request_effects(r, lkb, error);
2606 }
e7fd4179
DT		 2607 out:
2608 return error;
2609}
2610
3bcd3687 2611/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 2612
2613static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2614{
2615 int error;
2616
cf6620ac 2617 if (is_remote(r)) {
e7fd4179
DT		 2618 /* receive_convert() calls do_convert() on remote node */
2619 error = send_convert(r, lkb);
cf6620ac 2620 } else {
e7fd4179 2621 error = do_convert(r, lkb);
cf6620ac
DT		 2622 /* for remote locks the convert_reply is sent
2623 between do_convert and do_convert_effects */
2624 do_convert_effects(r, lkb, error);
2625 }
e7fd4179
DT		 2626
2627 return error;
2628}
2629
2630/* remove an existing lkb from the granted queue */
2631
2632static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2633{
2634 int error;
2635
cf6620ac 2636 if (is_remote(r)) {
e7fd4179
DT		 2637 /* receive_unlock() calls do_unlock() on remote node */
2638 error = send_unlock(r, lkb);
cf6620ac 2639 } else {
e7fd4179 2640 error = do_unlock(r, lkb);
cf6620ac
DT		 2641 /* for remote locks the unlock_reply is sent
2642 between do_unlock and do_unlock_effects */
2643 do_unlock_effects(r, lkb, error);
2644 }
e7fd4179
DT		 2645
2646 return error;
2647}
2648
2649/* remove an existing lkb from the convert or wait queue */
2650
2651static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2652{
2653 int error;
2654
cf6620ac 2655 if (is_remote(r)) {
e7fd4179
DT		 2656 /* receive_cancel() calls do_cancel() on remote node */
2657 error = send_cancel(r, lkb);
cf6620ac 2658 } else {
e7fd4179 2659 error = do_cancel(r, lkb);
cf6620ac
DT		 2660 /* for remote locks the cancel_reply is sent
2661 between do_cancel and do_cancel_effects */
2662 do_cancel_effects(r, lkb, error);
2663 }
e7fd4179
DT		 2664
2665 return error;
2666}
2667
2668/*
2669 * Four stage 2 varieties:
2670 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
2671 */
2672
2673static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
2674 int len, struct dlm_args *args)
2675{
2676 struct dlm_rsb *r;
2677 int error;
2678
2679 error = validate_lock_args(ls, lkb, args);
2680 if (error)
2681 goto out;
2682
2683 error = find_rsb(ls, name, len, R_CREATE, &r);
2684 if (error)
2685 goto out;
2686
2687 lock_rsb(r);
2688
2689 attach_lkb(r, lkb);
2690 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
2691
2692 error = _request_lock(r, lkb);
2693
2694 unlock_rsb(r);
2695 put_rsb(r);
2696
2697 out:
2698 return error;
2699}
2700
2701static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2702 struct dlm_args *args)
2703{
2704 struct dlm_rsb *r;
2705 int error;
2706
2707 r = lkb->lkb_resource;
2708
2709 hold_rsb(r);
2710 lock_rsb(r);
2711
2712 error = validate_lock_args(ls, lkb, args);
2713 if (error)
2714 goto out;
2715
2716 error = _convert_lock(r, lkb);
2717 out:
2718 unlock_rsb(r);
2719 put_rsb(r);
2720 return error;
2721}
2722
2723static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2724 struct dlm_args *args)
2725{
2726 struct dlm_rsb *r;
2727 int error;
2728
2729 r = lkb->lkb_resource;
2730
2731 hold_rsb(r);
2732 lock_rsb(r);
2733
2734 error = validate_unlock_args(lkb, args);
2735 if (error)
2736 goto out;
2737
2738 error = _unlock_lock(r, lkb);
2739 out:
2740 unlock_rsb(r);
2741 put_rsb(r);
2742 return error;
2743}
2744
2745static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
2746 struct dlm_args *args)
2747{
2748 struct dlm_rsb *r;
2749 int error;
2750
2751 r = lkb->lkb_resource;
2752
2753 hold_rsb(r);
2754 lock_rsb(r);
2755
2756 error = validate_unlock_args(lkb, args);
2757 if (error)
2758 goto out;
2759
2760 error = _cancel_lock(r, lkb);
2761 out:
2762 unlock_rsb(r);
2763 put_rsb(r);
2764 return error;
2765}
2766
2767/*
2768 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
2769 */
2770
2771int dlm_lock(dlm_lockspace_t *lockspace,
2772 int mode,
2773 struct dlm_lksb *lksb,
2774 uint32_t flags,
2775 void *name,
2776 unsigned int namelen,
2777 uint32_t parent_lkid,
2778 void (*ast) (void *astarg),
2779 void *astarg,
3bcd3687 2780 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 2781{
2782 struct dlm_ls *ls;
2783 struct dlm_lkb *lkb;
2784 struct dlm_args args;
2785 int error, convert = flags & DLM_LKF_CONVERT;
2786
2787 ls = dlm_find_lockspace_local(lockspace);
2788 if (!ls)
2789 return -EINVAL;
2790
85e86edf 2791 dlm_lock_recovery(ls);
e7fd4179
DT		 2792
2793 if (convert)
2794 error = find_lkb(ls, lksb->sb_lkid, &lkb);
2795 else
2796 error = create_lkb(ls, &lkb);
2797
2798 if (error)
2799 goto out;
2800
d7db923e 2801 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 2802 astarg, bast, &args);
e7fd4179
DT		 2803 if (error)
2804 goto out_put;
2805
2806 if (convert)
2807 error = convert_lock(ls, lkb, &args);
2808 else
2809 error = request_lock(ls, lkb, name, namelen, &args);
2810
2811 if (error == -EINPROGRESS)
2812 error = 0;
2813 out_put:
2814 if (convert || error)
b3f58d8f 2815 __put_lkb(ls, lkb);
c85d65e9 2816 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 2817 error = 0;
2818 out:
85e86edf 2819 dlm_unlock_recovery(ls);
e7fd4179
DT		 2820 dlm_put_lockspace(ls);
2821 return error;
2822}
2823
2824int dlm_unlock(dlm_lockspace_t *lockspace,
2825 uint32_t lkid,
2826 uint32_t flags,
2827 struct dlm_lksb *lksb,
2828 void *astarg)
2829{
2830 struct dlm_ls *ls;
2831 struct dlm_lkb *lkb;
2832 struct dlm_args args;
2833 int error;
2834
2835 ls = dlm_find_lockspace_local(lockspace);
2836 if (!ls)
2837 return -EINVAL;
2838
85e86edf 2839 dlm_lock_recovery(ls);
e7fd4179
DT		 2840
2841 error = find_lkb(ls, lkid, &lkb);
2842 if (error)
2843 goto out;
2844
2845 error = set_unlock_args(flags, astarg, &args);
2846 if (error)
2847 goto out_put;
2848
2849 if (flags & DLM_LKF_CANCEL)
2850 error = cancel_lock(ls, lkb, &args);
2851 else
2852 error = unlock_lock(ls, lkb, &args);
2853
2854 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
2855 error = 0;
ef0c2bb0
DT		 2856 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
2857 error = 0;
e7fd4179 2858 out_put:
b3f58d8f 2859 dlm_put_lkb(lkb);
e7fd4179 2860 out:
85e86edf 2861 dlm_unlock_recovery(ls);
e7fd4179
DT		 2862 dlm_put_lockspace(ls);
2863 return error;
2864}
2865
2866/*
2867 * send/receive routines for remote operations and replies
2868 *
2869 * send_args
2870 * send_common
2871 * send_request receive_request
2872 * send_convert receive_convert
2873 * send_unlock receive_unlock
2874 * send_cancel receive_cancel
2875 * send_grant receive_grant
2876 * send_bast receive_bast
2877 * send_lookup receive_lookup
2878 * send_remove receive_remove
2879 *
2880 * send_common_reply
2881 * receive_request_reply send_request_reply
2882 * receive_convert_reply send_convert_reply
2883 * receive_unlock_reply send_unlock_reply
2884 * receive_cancel_reply send_cancel_reply
2885 * receive_lookup_reply send_lookup_reply
2886 */
2887
7e4dac33
DT		 2888static int _create_message(struct dlm_ls *ls, int mb_len,
2889 int to_nodeid, int mstype,
2890 struct dlm_message **ms_ret,
2891 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 2892{
2893 struct dlm_message *ms;
2894 struct dlm_mhandle *mh;
2895 char *mb;
e7fd4179
DT		 2896
2897 /* get_buffer gives us a message handle (mh) that we need to
2898 pass into lowcomms_commit and a message buffer (mb) that we
2899 write our data into */
2900
573c24c4 2901 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
e7fd4179
DT		 2902 if (!mh)
2903 return -ENOBUFS;
2904
2905 memset(mb, 0, mb_len);
2906
2907 ms = (struct dlm_message *) mb;
2908
2909 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 2910 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 2911 ms->m_header.h_nodeid = dlm_our_nodeid();
2912 ms->m_header.h_length = mb_len;
2913 ms->m_header.h_cmd = DLM_MSG;
2914
2915 ms->m_type = mstype;
2916
2917 *mh_ret = mh;
2918 *ms_ret = ms;
2919 return 0;
2920}
2921
7e4dac33
DT		 2922static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
2923 int to_nodeid, int mstype,
2924 struct dlm_message **ms_ret,
2925 struct dlm_mhandle **mh_ret)
2926{
2927 int mb_len = sizeof(struct dlm_message);
2928
2929 switch (mstype) {
2930 case DLM_MSG_REQUEST:
2931 case DLM_MSG_LOOKUP:
2932 case DLM_MSG_REMOVE:
2933 mb_len += r->res_length;
2934 break;
2935 case DLM_MSG_CONVERT:
2936 case DLM_MSG_UNLOCK:
2937 case DLM_MSG_REQUEST_REPLY:
2938 case DLM_MSG_CONVERT_REPLY:
2939 case DLM_MSG_GRANT:
2940 if (lkb && lkb->lkb_lvbptr)
2941 mb_len += r->res_ls->ls_lvblen;
2942 break;
2943 }
2944
2945 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
2946 ms_ret, mh_ret);
2947}
2948
e7fd4179
DT		 2949/* further lowcomms enhancements or alternate implementations may make
2950 the return value from this function useful at some point */
2951
2952static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
2953{
2954 dlm_message_out(ms);
2955 dlm_lowcomms_commit_buffer(mh);
2956 return 0;
2957}
2958
2959static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
2960 struct dlm_message *ms)
2961{
2962 ms->m_nodeid = lkb->lkb_nodeid;
2963 ms->m_pid = lkb->lkb_ownpid;
2964 ms->m_lkid = lkb->lkb_id;
2965 ms->m_remid = lkb->lkb_remid;
2966 ms->m_exflags = lkb->lkb_exflags;
2967 ms->m_sbflags = lkb->lkb_sbflags;
2968 ms->m_flags = lkb->lkb_flags;
2969 ms->m_lvbseq = lkb->lkb_lvbseq;
2970 ms->m_status = lkb->lkb_status;
2971 ms->m_grmode = lkb->lkb_grmode;
2972 ms->m_rqmode = lkb->lkb_rqmode;
2973 ms->m_hash = r->res_hash;
2974
2975 /* m_result and m_bastmode are set from function args,
2976 not from lkb fields */
2977
e5dae548 2978 if (lkb->lkb_bastfn)
8304d6f2 2979 ms->m_asts |= DLM_CB_BAST;
e5dae548 2980 if (lkb->lkb_astfn)
8304d6f2 2981 ms->m_asts |= DLM_CB_CAST;
e7fd4179 2982
da49f36f
DT		 2983 /* compare with switch in create_message; send_remove() doesn't
2984 use send_args() */
e7fd4179 2985
da49f36f
DT		 2986 switch (ms->m_type) {
2987 case DLM_MSG_REQUEST:
2988 case DLM_MSG_LOOKUP:
2989 memcpy(ms->m_extra, r->res_name, r->res_length);
2990 break;
2991 case DLM_MSG_CONVERT:
2992 case DLM_MSG_UNLOCK:
2993 case DLM_MSG_REQUEST_REPLY:
2994 case DLM_MSG_CONVERT_REPLY:
2995 case DLM_MSG_GRANT:
2996 if (!lkb->lkb_lvbptr)
2997 break;
e7fd4179 2998 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 2999 break;
3000 }
e7fd4179
DT		 3001}
3002
3003static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3004{
3005 struct dlm_message *ms;
3006 struct dlm_mhandle *mh;
3007 int to_nodeid, error;
3008
c6ff669b
DT		 3009 to_nodeid = r->res_nodeid;
3010
3011 error = add_to_waiters(lkb, mstype, to_nodeid);
ef0c2bb0
DT		 3012 if (error)
3013 return error;
e7fd4179 3014
e7fd4179
DT		 3015 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3016 if (error)
3017 goto fail;
3018
3019 send_args(r, lkb, ms);
3020
3021 error = send_message(mh, ms);
3022 if (error)
3023 goto fail;
3024 return 0;
3025
3026 fail:
ef0c2bb0 3027 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 3028 return error;
3029}
3030
3031static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3032{
3033 return send_common(r, lkb, DLM_MSG_REQUEST);
3034}
3035
3036static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3037{
3038 int error;
3039
3040 error = send_common(r, lkb, DLM_MSG_CONVERT);
3041
3042 /* down conversions go without a reply from the master */
3043 if (!error && down_conversion(lkb)) {
ef0c2bb0 3044 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2a7ce0ed 3045 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
ef0c2bb0 3046 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179
DT		 3047 r->res_ls->ls_stub_ms.m_result = 0;
3048 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3049 }
3050
3051 return error;
3052}
3053
3054/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3055 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3056 that the master is still correct. */
3057
3058static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3059{
3060 return send_common(r, lkb, DLM_MSG_UNLOCK);
3061}
3062
3063static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3064{
3065 return send_common(r, lkb, DLM_MSG_CANCEL);
3066}
3067
3068static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3069{
3070 struct dlm_message *ms;
3071 struct dlm_mhandle *mh;
3072 int to_nodeid, error;
3073
3074 to_nodeid = lkb->lkb_nodeid;
3075
3076 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3077 if (error)
3078 goto out;
3079
3080 send_args(r, lkb, ms);
3081
3082 ms->m_result = 0;
3083
3084 error = send_message(mh, ms);
3085 out:
3086 return error;
3087}
3088
3089static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3090{
3091 struct dlm_message *ms;
3092 struct dlm_mhandle *mh;
3093 int to_nodeid, error;
3094
3095 to_nodeid = lkb->lkb_nodeid;
3096
3097 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3098 if (error)
3099 goto out;
3100
3101 send_args(r, lkb, ms);
3102
3103 ms->m_bastmode = mode;
3104
3105 error = send_message(mh, ms);
3106 out:
3107 return error;
3108}
3109
3110static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3111{
3112 struct dlm_message *ms;
3113 struct dlm_mhandle *mh;
3114 int to_nodeid, error;
3115
c6ff669b
DT		 3116 to_nodeid = dlm_dir_nodeid(r);
3117
3118 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
ef0c2bb0
DT		 3119 if (error)
3120 return error;
e7fd4179 3121
e7fd4179
DT		 3122 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3123 if (error)
3124 goto fail;
3125
3126 send_args(r, lkb, ms);
3127
3128 error = send_message(mh, ms);
3129 if (error)
3130 goto fail;
3131 return 0;
3132
3133 fail:
ef0c2bb0 3134 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 3135 return error;
3136}
3137
3138static int send_remove(struct dlm_rsb *r)
3139{
3140 struct dlm_message *ms;
3141 struct dlm_mhandle *mh;
3142 int to_nodeid, error;
3143
3144 to_nodeid = dlm_dir_nodeid(r);
3145
3146 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3147 if (error)
3148 goto out;
3149
3150 memcpy(ms->m_extra, r->res_name, r->res_length);
3151 ms->m_hash = r->res_hash;
3152
3153 error = send_message(mh, ms);
3154 out:
3155 return error;
3156}
3157
3158static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3159 int mstype, int rv)
3160{
3161 struct dlm_message *ms;
3162 struct dlm_mhandle *mh;
3163 int to_nodeid, error;
3164
3165 to_nodeid = lkb->lkb_nodeid;
3166
3167 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3168 if (error)
3169 goto out;
3170
3171 send_args(r, lkb, ms);
3172
3173 ms->m_result = rv;
3174
3175 error = send_message(mh, ms);
3176 out:
3177 return error;
3178}
3179
3180static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3181{
3182 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3183}
3184
3185static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3186{
3187 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3188}
3189
3190static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3191{
3192 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3193}
3194
3195static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3196{
3197 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3198}
3199
3200static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3201 int ret_nodeid, int rv)
3202{
3203 struct dlm_rsb *r = &ls->ls_stub_rsb;
3204 struct dlm_message *ms;
3205 struct dlm_mhandle *mh;
3206 int error, nodeid = ms_in->m_header.h_nodeid;
3207
3208 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3209 if (error)
3210 goto out;
3211
3212 ms->m_lkid = ms_in->m_lkid;
3213 ms->m_result = rv;
3214 ms->m_nodeid = ret_nodeid;
3215
3216 error = send_message(mh, ms);
3217 out:
3218 return error;
3219}
3220
3221/* which args we save from a received message depends heavily on the type
3222 of message, unlike the send side where we can safely send everything about
3223 the lkb for any type of message */
3224
3225static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3226{
3227 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 3228 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 3229 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3230 (ms->m_flags & 0x0000FFFF);
3231}
3232
3233static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3234{
2a7ce0ed
DT		 3235 if (ms->m_flags == DLM_IFL_STUB_MS)
3236 return;
3237
e7fd4179
DT		 3238 lkb->lkb_sbflags = ms->m_sbflags;
3239 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3240 (ms->m_flags & 0x0000FFFF);
3241}
3242
3243static int receive_extralen(struct dlm_message *ms)
3244{
3245 return (ms->m_header.h_length - sizeof(struct dlm_message));
3246}
3247
e7fd4179
DT		 3248static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3249 struct dlm_message *ms)
3250{
3251 int len;
3252
3253 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3254 if (!lkb->lkb_lvbptr)
52bda2b5 3255 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 3256 if (!lkb->lkb_lvbptr)
3257 return -ENOMEM;
3258 len = receive_extralen(ms);
a9cc9159
AV		 3259 if (len > DLM_RESNAME_MAXLEN)
3260 len = DLM_RESNAME_MAXLEN;
e7fd4179
DT		 3261 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3262 }
3263 return 0;
3264}
3265
e5dae548
DT		 3266static void fake_bastfn(void *astparam, int mode)
3267{
3268 log_print("fake_bastfn should not be called");
3269}
3270
3271static void fake_astfn(void *astparam)
3272{
3273 log_print("fake_astfn should not be called");
3274}
3275
e7fd4179
DT		 3276static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3277 struct dlm_message *ms)
3278{
3279 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3280 lkb->lkb_ownpid = ms->m_pid;
3281 lkb->lkb_remid = ms->m_lkid;
3282 lkb->lkb_grmode = DLM_LOCK_IV;
3283 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548 3284
8304d6f2
DT		 3285 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3286 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 3287
8d07fd50
DT		 3288 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3289 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3290 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3291 if (!lkb->lkb_lvbptr)
3292 return -ENOMEM;
3293 }
e7fd4179
DT		 3294
3295 return 0;
3296}
3297
3298static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3299 struct dlm_message *ms)
3300{
e7fd4179
DT		 3301 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3302 return -EBUSY;
3303
e7fd4179
DT		 3304 if (receive_lvb(ls, lkb, ms))
3305 return -ENOMEM;
3306
3307 lkb->lkb_rqmode = ms->m_rqmode;
3308 lkb->lkb_lvbseq = ms->m_lvbseq;
3309
3310 return 0;
3311}
3312
3313static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3314 struct dlm_message *ms)
3315{
e7fd4179
DT		 3316 if (receive_lvb(ls, lkb, ms))
3317 return -ENOMEM;
3318 return 0;
3319}
3320
3321/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3322 uses to send a reply and that the remote end uses to process the reply. */
3323
3324static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3325{
3326 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3327 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3328 lkb->lkb_remid = ms->m_lkid;
3329}
3330
c54e04b0
DT		 3331/* This is called after the rsb is locked so that we can safely inspect
3332 fields in the lkb. */
3333
3334static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3335{
3336 int from = ms->m_header.h_nodeid;
3337 int error = 0;
3338
3339 switch (ms->m_type) {
3340 case DLM_MSG_CONVERT:
3341 case DLM_MSG_UNLOCK:
3342 case DLM_MSG_CANCEL:
3343 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3344 error = -EINVAL;
3345 break;
3346
3347 case DLM_MSG_CONVERT_REPLY:
3348 case DLM_MSG_UNLOCK_REPLY:
3349 case DLM_MSG_CANCEL_REPLY:
3350 case DLM_MSG_GRANT:
3351 case DLM_MSG_BAST:
3352 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3353 error = -EINVAL;
3354 break;
3355
3356 case DLM_MSG_REQUEST_REPLY:
3357 if (!is_process_copy(lkb))
3358 error = -EINVAL;
3359 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3360 error = -EINVAL;
3361 break;
3362
3363 default:
3364 error = -EINVAL;
3365 }
3366
3367 if (error)
3368 log_error(lkb->lkb_resource->res_ls,
3369 "ignore invalid message %d from %d %x %x %x %d",
3370 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
3371 lkb->lkb_flags, lkb->lkb_nodeid);
3372 return error;
3373}
3374
e7fd4179
DT		 3375static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
3376{
3377 struct dlm_lkb *lkb;
3378 struct dlm_rsb *r;
3379 int error, namelen;
3380
3381 error = create_lkb(ls, &lkb);
3382 if (error)
3383 goto fail;
3384
3385 receive_flags(lkb, ms);
3386 lkb->lkb_flags |= DLM_IFL_MSTCPY;
3387 error = receive_request_args(ls, lkb, ms);
3388 if (error) {
b3f58d8f 3389 __put_lkb(ls, lkb);
e7fd4179
DT		 3390 goto fail;
3391 }
3392
3393 namelen = receive_extralen(ms);
3394
3395 error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r);
3396 if (error) {
b3f58d8f 3397 __put_lkb(ls, lkb);
e7fd4179
DT		 3398 goto fail;
3399 }
3400
3401 lock_rsb(r);
3402
3403 attach_lkb(r, lkb);
3404 error = do_request(r, lkb);
3405 send_request_reply(r, lkb, error);
cf6620ac 3406 do_request_effects(r, lkb, error);
e7fd4179
DT		 3407
3408 unlock_rsb(r);
3409 put_rsb(r);
3410
3411 if (error == -EINPROGRESS)
3412 error = 0;
3413 if (error)
b3f58d8f 3414 dlm_put_lkb(lkb);
e7fd4179
DT		 3415 return;
3416
3417 fail:
3418 setup_stub_lkb(ls, ms);
3419 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3420}
3421
3422static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
3423{
3424 struct dlm_lkb *lkb;
3425 struct dlm_rsb *r;
90135925 3426 int error, reply = 1;
e7fd4179
DT		 3427
3428 error = find_lkb(ls, ms->m_remid, &lkb);
3429 if (error)
3430 goto fail;
3431
3432 r = lkb->lkb_resource;
3433
3434 hold_rsb(r);
3435 lock_rsb(r);
3436
c54e04b0
DT		 3437 error = validate_message(lkb, ms);
3438 if (error)
3439 goto out;
3440
e7fd4179 3441 receive_flags(lkb, ms);
cf6620ac 3442
e7fd4179 3443 error = receive_convert_args(ls, lkb, ms);
cf6620ac
DT		 3444 if (error) {
3445 send_convert_reply(r, lkb, error);
3446 goto out;
3447 }
3448
e7fd4179
DT		 3449 reply = !down_conversion(lkb);
3450
3451 error = do_convert(r, lkb);
e7fd4179
DT		 3452 if (reply)
3453 send_convert_reply(r, lkb, error);
cf6620ac 3454 do_convert_effects(r, lkb, error);
c54e04b0 3455 out:
e7fd4179
DT		 3456 unlock_rsb(r);
3457 put_rsb(r);
b3f58d8f 3458 dlm_put_lkb(lkb);
e7fd4179
DT		 3459 return;
3460
3461 fail:
3462 setup_stub_lkb(ls, ms);
3463 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3464}
3465
3466static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
3467{
3468 struct dlm_lkb *lkb;
3469 struct dlm_rsb *r;
3470 int error;
3471
3472 error = find_lkb(ls, ms->m_remid, &lkb);
3473 if (error)
3474 goto fail;
3475
3476 r = lkb->lkb_resource;
3477
3478 hold_rsb(r);
3479 lock_rsb(r);
3480
c54e04b0
DT		 3481 error = validate_message(lkb, ms);
3482 if (error)
3483 goto out;
3484
e7fd4179 3485 receive_flags(lkb, ms);
cf6620ac 3486
e7fd4179 3487 error = receive_unlock_args(ls, lkb, ms);
cf6620ac
DT		 3488 if (error) {
3489 send_unlock_reply(r, lkb, error);
3490 goto out;
3491 }
e7fd4179
DT		 3492
3493 error = do_unlock(r, lkb);
e7fd4179 3494 send_unlock_reply(r, lkb, error);
cf6620ac 3495 do_unlock_effects(r, lkb, error);
c54e04b0 3496 out:
e7fd4179
DT		 3497 unlock_rsb(r);
3498 put_rsb(r);
b3f58d8f 3499 dlm_put_lkb(lkb);
e7fd4179
DT		 3500 return;
3501
3502 fail:
3503 setup_stub_lkb(ls, ms);
3504 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3505}
3506
3507static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
3508{
3509 struct dlm_lkb *lkb;
3510 struct dlm_rsb *r;
3511 int error;
3512
3513 error = find_lkb(ls, ms->m_remid, &lkb);
3514 if (error)
3515 goto fail;
3516
3517 receive_flags(lkb, ms);
3518
3519 r = lkb->lkb_resource;
3520
3521 hold_rsb(r);
3522 lock_rsb(r);
3523
c54e04b0
DT		 3524 error = validate_message(lkb, ms);
3525 if (error)
3526 goto out;
3527
e7fd4179
DT		 3528 error = do_cancel(r, lkb);
3529 send_cancel_reply(r, lkb, error);
cf6620ac 3530 do_cancel_effects(r, lkb, error);
c54e04b0 3531 out:
e7fd4179
DT		 3532 unlock_rsb(r);
3533 put_rsb(r);
b3f58d8f 3534 dlm_put_lkb(lkb);
e7fd4179
DT		 3535 return;
3536
3537 fail:
3538 setup_stub_lkb(ls, ms);
3539 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
3540}
3541
3542static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
3543{
3544 struct dlm_lkb *lkb;
3545 struct dlm_rsb *r;
3546 int error;
3547
3548 error = find_lkb(ls, ms->m_remid, &lkb);
3549 if (error) {
c54e04b0
DT		 3550 log_debug(ls, "receive_grant from %d no lkb %x",
3551 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3552 return;
3553 }
e7fd4179
DT		 3554
3555 r = lkb->lkb_resource;
3556
3557 hold_rsb(r);
3558 lock_rsb(r);
3559
c54e04b0
DT		 3560 error = validate_message(lkb, ms);
3561 if (error)
3562 goto out;
3563
e7fd4179 3564 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 3565 if (is_altmode(lkb))
3566 munge_altmode(lkb, ms);
e7fd4179
DT		 3567 grant_lock_pc(r, lkb, ms);
3568 queue_cast(r, lkb, 0);
c54e04b0 3569 out:
e7fd4179
DT		 3570 unlock_rsb(r);
3571 put_rsb(r);
b3f58d8f 3572 dlm_put_lkb(lkb);
e7fd4179
DT		 3573}
3574
3575static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
3576{
3577 struct dlm_lkb *lkb;
3578 struct dlm_rsb *r;
3579 int error;
3580
3581 error = find_lkb(ls, ms->m_remid, &lkb);
3582 if (error) {
c54e04b0
DT		 3583 log_debug(ls, "receive_bast from %d no lkb %x",
3584 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3585 return;
3586 }
e7fd4179
DT		 3587
3588 r = lkb->lkb_resource;
3589
3590 hold_rsb(r);
3591 lock_rsb(r);
3592
c54e04b0
DT		 3593 error = validate_message(lkb, ms);
3594 if (error)
3595 goto out;
e7fd4179 3596
c54e04b0
DT		 3597 queue_bast(r, lkb, ms->m_bastmode);
3598 out:
e7fd4179
DT		 3599 unlock_rsb(r);
3600 put_rsb(r);
b3f58d8f 3601 dlm_put_lkb(lkb);
e7fd4179
DT		 3602}
3603
3604static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
3605{
3606 int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid;
3607
3608 from_nodeid = ms->m_header.h_nodeid;
3609 our_nodeid = dlm_our_nodeid();
3610
3611 len = receive_extralen(ms);
3612
3613 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3614 if (dir_nodeid != our_nodeid) {
3615 log_error(ls, "lookup dir_nodeid %d from %d",
3616 dir_nodeid, from_nodeid);
3617 error = -EINVAL;
3618 ret_nodeid = -1;
3619 goto out;
3620 }
3621
3622 error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid);
3623
3624 /* Optimization: we're master so treat lookup as a request */
3625 if (!error && ret_nodeid == our_nodeid) {
3626 receive_request(ls, ms);
3627 return;
3628 }
3629 out:
3630 send_lookup_reply(ls, ms, ret_nodeid, error);
3631}
3632
3633static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
3634{
3635 int len, dir_nodeid, from_nodeid;
3636
3637 from_nodeid = ms->m_header.h_nodeid;
3638
3639 len = receive_extralen(ms);
3640
3641 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
3642 if (dir_nodeid != dlm_our_nodeid()) {
3643 log_error(ls, "remove dir entry dir_nodeid %d from %d",
3644 dir_nodeid, from_nodeid);
3645 return;
3646 }
3647
3648 dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len);
3649}
3650
8499137d
DT		 3651static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
3652{
3653 do_purge(ls, ms->m_nodeid, ms->m_pid);
3654}
3655
e7fd4179
DT		 3656static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
3657{
3658 struct dlm_lkb *lkb;
3659 struct dlm_rsb *r;
ef0c2bb0 3660 int error, mstype, result;
e7fd4179
DT		 3661
3662 error = find_lkb(ls, ms->m_remid, &lkb);
3663 if (error) {
c54e04b0
DT		 3664 log_debug(ls, "receive_request_reply from %d no lkb %x",
3665 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3666 return;
3667 }
e7fd4179 3668
e7fd4179
DT		 3669 r = lkb->lkb_resource;
3670 hold_rsb(r);
3671 lock_rsb(r);
3672
c54e04b0
DT		 3673 error = validate_message(lkb, ms);
3674 if (error)
3675 goto out;
3676
ef0c2bb0
DT		 3677 mstype = lkb->lkb_wait_type;
3678 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
3679 if (error)
3680 goto out;
3681
e7fd4179
DT		 3682 /* Optimization: the dir node was also the master, so it took our
3683 lookup as a request and sent request reply instead of lookup reply */
3684 if (mstype == DLM_MSG_LOOKUP) {
3685 r->res_nodeid = ms->m_header.h_nodeid;
3686 lkb->lkb_nodeid = r->res_nodeid;
3687 }
3688
ef0c2bb0
DT		 3689 /* this is the value returned from do_request() on the master */
3690 result = ms->m_result;
3691
3692 switch (result) {
e7fd4179 3693 case -EAGAIN:
ef0c2bb0 3694 /* request would block (be queued) on remote master */
e7fd4179
DT		 3695 queue_cast(r, lkb, -EAGAIN);
3696 confirm_master(r, -EAGAIN);
ef0c2bb0 3697 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 3698 break;
3699
3700 case -EINPROGRESS:
3701 case 0:
3702 /* request was queued or granted on remote master */
3703 receive_flags_reply(lkb, ms);
3704 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 3705 if (is_altmode(lkb))
3706 munge_altmode(lkb, ms);
3ae1acf9 3707 if (result) {
e7fd4179 3708 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 3709 add_timeout(lkb);
3710 } else {
e7fd4179
DT		 3711 grant_lock_pc(r, lkb, ms);
3712 queue_cast(r, lkb, 0);
3713 }
ef0c2bb0 3714 confirm_master(r, result);
e7fd4179
DT		 3715 break;
3716
597d0cae 3717 case -EBADR:
e7fd4179
DT		 3718 case -ENOTBLK:
3719 /* find_rsb failed to find rsb or rsb wasn't master */
ef0c2bb0
DT		 3720 log_debug(ls, "receive_request_reply %x %x master diff %d %d",
3721 lkb->lkb_id, lkb->lkb_flags, r->res_nodeid, result);
e7fd4179
DT		 3722 r->res_nodeid = -1;
3723 lkb->lkb_nodeid = -1;
ef0c2bb0
DT		 3724
3725 if (is_overlap(lkb)) {
3726 /* we'll ignore error in cancel/unlock reply */
3727 queue_cast_overlap(r, lkb);
aec64e1b 3728 confirm_master(r, result);
ef0c2bb0
DT		 3729 unhold_lkb(lkb); /* undoes create_lkb() */
3730 } else
3731 _request_lock(r, lkb);
e7fd4179
DT		 3732 break;
3733
3734 default:
ef0c2bb0
DT		 3735 log_error(ls, "receive_request_reply %x error %d",
3736 lkb->lkb_id, result);
e7fd4179
DT		 3737 }
3738
ef0c2bb0
DT		 3739 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
3740 log_debug(ls, "receive_request_reply %x result %d unlock",
3741 lkb->lkb_id, result);
3742 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3743 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3744 send_unlock(r, lkb);
3745 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
3746 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
3747 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3748 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3749 send_cancel(r, lkb);
3750 } else {
3751 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
3752 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
3753 }
3754 out:
e7fd4179
DT		 3755 unlock_rsb(r);
3756 put_rsb(r);
b3f58d8f 3757 dlm_put_lkb(lkb);
e7fd4179
DT		 3758}
3759
3760static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3761 struct dlm_message *ms)
3762{
e7fd4179 3763 /* this is the value returned from do_convert() on the master */
ef0c2bb0 3764 switch (ms->m_result) {
e7fd4179
DT		 3765 case -EAGAIN:
3766 /* convert would block (be queued) on remote master */
3767 queue_cast(r, lkb, -EAGAIN);
3768 break;
3769
c85d65e9
DT		 3770 case -EDEADLK:
3771 receive_flags_reply(lkb, ms);
3772 revert_lock_pc(r, lkb);
3773 queue_cast(r, lkb, -EDEADLK);
3774 break;
3775
e7fd4179
DT		 3776 case -EINPROGRESS:
3777 /* convert was queued on remote master */
7d3c1feb
DT		 3778 receive_flags_reply(lkb, ms);
3779 if (is_demoted(lkb))
2a7ce0ed 3780 munge_demoted(lkb);
e7fd4179
DT		 3781 del_lkb(r, lkb);
3782 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3783 add_timeout(lkb);
e7fd4179
DT		 3784 break;
3785
3786 case 0:
3787 /* convert was granted on remote master */
3788 receive_flags_reply(lkb, ms);
7d3c1feb 3789 if (is_demoted(lkb))
2a7ce0ed 3790 munge_demoted(lkb);
e7fd4179
DT		 3791 grant_lock_pc(r, lkb, ms);
3792 queue_cast(r, lkb, 0);
3793 break;
3794
3795 default:
ef0c2bb0
DT		 3796 log_error(r->res_ls, "receive_convert_reply %x error %d",
3797 lkb->lkb_id, ms->m_result);
e7fd4179
DT		 3798 }
3799}
3800
3801static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3802{
3803 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3804 int error;
e7fd4179
DT		 3805
3806 hold_rsb(r);
3807 lock_rsb(r);
3808
c54e04b0
DT		 3809 error = validate_message(lkb, ms);
3810 if (error)
3811 goto out;
3812
ef0c2bb0
DT		 3813 /* stub reply can happen with waiters_mutex held */
3814 error = remove_from_waiters_ms(lkb, ms);
3815 if (error)
3816 goto out;
e7fd4179 3817
ef0c2bb0
DT		 3818 __receive_convert_reply(r, lkb, ms);
3819 out:
e7fd4179
DT		 3820 unlock_rsb(r);
3821 put_rsb(r);
3822}
3823
3824static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
3825{
3826 struct dlm_lkb *lkb;
3827 int error;
3828
3829 error = find_lkb(ls, ms->m_remid, &lkb);
3830 if (error) {
c54e04b0
DT		 3831 log_debug(ls, "receive_convert_reply from %d no lkb %x",
3832 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3833 return;
3834 }
e7fd4179 3835
e7fd4179 3836 _receive_convert_reply(lkb, ms);
b3f58d8f 3837 dlm_put_lkb(lkb);
e7fd4179
DT		 3838}
3839
3840static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3841{
3842 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3843 int error;
e7fd4179
DT		 3844
3845 hold_rsb(r);
3846 lock_rsb(r);
3847
c54e04b0
DT		 3848 error = validate_message(lkb, ms);
3849 if (error)
3850 goto out;
3851
ef0c2bb0
DT		 3852 /* stub reply can happen with waiters_mutex held */
3853 error = remove_from_waiters_ms(lkb, ms);
3854 if (error)
3855 goto out;
3856
e7fd4179
DT		 3857 /* this is the value returned from do_unlock() on the master */
3858
ef0c2bb0 3859 switch (ms->m_result) {
e7fd4179
DT		 3860 case -DLM_EUNLOCK:
3861 receive_flags_reply(lkb, ms);
3862 remove_lock_pc(r, lkb);
3863 queue_cast(r, lkb, -DLM_EUNLOCK);
3864 break;
ef0c2bb0
DT		 3865 case -ENOENT:
3866 break;
e7fd4179 3867 default:
ef0c2bb0
DT		 3868 log_error(r->res_ls, "receive_unlock_reply %x error %d",
3869 lkb->lkb_id, ms->m_result);
e7fd4179 3870 }
ef0c2bb0 3871 out:
e7fd4179
DT		 3872 unlock_rsb(r);
3873 put_rsb(r);
3874}
3875
3876static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
3877{
3878 struct dlm_lkb *lkb;
3879 int error;
3880
3881 error = find_lkb(ls, ms->m_remid, &lkb);
3882 if (error) {
c54e04b0
DT		 3883 log_debug(ls, "receive_unlock_reply from %d no lkb %x",
3884 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3885 return;
3886 }
e7fd4179 3887
e7fd4179 3888 _receive_unlock_reply(lkb, ms);
b3f58d8f 3889 dlm_put_lkb(lkb);
e7fd4179
DT		 3890}
3891
3892static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3893{
3894 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 3895 int error;
e7fd4179
DT		 3896
3897 hold_rsb(r);
3898 lock_rsb(r);
3899
c54e04b0
DT		 3900 error = validate_message(lkb, ms);
3901 if (error)
3902 goto out;
3903
ef0c2bb0
DT		 3904 /* stub reply can happen with waiters_mutex held */
3905 error = remove_from_waiters_ms(lkb, ms);
3906 if (error)
3907 goto out;
3908
e7fd4179
DT		 3909 /* this is the value returned from do_cancel() on the master */
3910
ef0c2bb0 3911 switch (ms->m_result) {
e7fd4179
DT		 3912 case -DLM_ECANCEL:
3913 receive_flags_reply(lkb, ms);
3914 revert_lock_pc(r, lkb);
84d8cd69 3915 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3916 break;
3917 case 0:
e7fd4179
DT		 3918 break;
3919 default:
ef0c2bb0
DT		 3920 log_error(r->res_ls, "receive_cancel_reply %x error %d",
3921 lkb->lkb_id, ms->m_result);
e7fd4179 3922 }
ef0c2bb0 3923 out:
e7fd4179
DT		 3924 unlock_rsb(r);
3925 put_rsb(r);
3926}
3927
3928static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
3929{
3930 struct dlm_lkb *lkb;
3931 int error;
3932
3933 error = find_lkb(ls, ms->m_remid, &lkb);
3934 if (error) {
c54e04b0
DT		 3935 log_debug(ls, "receive_cancel_reply from %d no lkb %x",
3936 ms->m_header.h_nodeid, ms->m_remid);
e7fd4179
DT		 3937 return;
3938 }
e7fd4179 3939
e7fd4179 3940 _receive_cancel_reply(lkb, ms);
b3f58d8f 3941 dlm_put_lkb(lkb);
e7fd4179
DT		 3942}
3943
3944static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
3945{
3946 struct dlm_lkb *lkb;
3947 struct dlm_rsb *r;
3948 int error, ret_nodeid;
3949
3950 error = find_lkb(ls, ms->m_lkid, &lkb);
3951 if (error) {
3952 log_error(ls, "receive_lookup_reply no lkb");
3953 return;
3954 }
3955
ef0c2bb0 3956 /* ms->m_result is the value returned by dlm_dir_lookup on dir node
e7fd4179 3957 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 3958
3959 r = lkb->lkb_resource;
3960 hold_rsb(r);
3961 lock_rsb(r);
3962
ef0c2bb0
DT		 3963 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
3964 if (error)
3965 goto out;
3966
e7fd4179
DT		 3967 ret_nodeid = ms->m_nodeid;
3968 if (ret_nodeid == dlm_our_nodeid()) {
3969 r->res_nodeid = 0;
3970 ret_nodeid = 0;
3971 r->res_first_lkid = 0;
3972 } else {
3973 /* set_master() will copy res_nodeid to lkb_nodeid */
3974 r->res_nodeid = ret_nodeid;
3975 }
3976
ef0c2bb0
DT		 3977 if (is_overlap(lkb)) {
3978 log_debug(ls, "receive_lookup_reply %x unlock %x",
3979 lkb->lkb_id, lkb->lkb_flags);
3980 queue_cast_overlap(r, lkb);
3981 unhold_lkb(lkb); /* undoes create_lkb() */
3982 goto out_list;
3983 }
3984
e7fd4179
DT		 3985 _request_lock(r, lkb);
3986
ef0c2bb0 3987 out_list:
e7fd4179
DT		 3988 if (!ret_nodeid)
3989 process_lookup_list(r);
ef0c2bb0 3990 out:
e7fd4179
DT		 3991 unlock_rsb(r);
3992 put_rsb(r);
b3f58d8f 3993 dlm_put_lkb(lkb);
e7fd4179
DT		 3994}
3995
c36258b5 3996static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179 3997{
46b43eed
DT		 3998 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
3999 log_debug(ls, "ignore non-member message %d from %d %x %x %d",
4000 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4001 ms->m_remid, ms->m_result);
4002 return;
4003 }
4004
e7fd4179
DT		 4005 switch (ms->m_type) {
4006
4007 /* messages sent to a master node */
4008
4009 case DLM_MSG_REQUEST:
4010 receive_request(ls, ms);
4011 break;
4012
4013 case DLM_MSG_CONVERT:
4014 receive_convert(ls, ms);
4015 break;
4016
4017 case DLM_MSG_UNLOCK:
4018 receive_unlock(ls, ms);
4019 break;
4020
4021 case DLM_MSG_CANCEL:
4022 receive_cancel(ls, ms);
4023 break;
4024
4025 /* messages sent from a master node (replies to above) */
4026
4027 case DLM_MSG_REQUEST_REPLY:
4028 receive_request_reply(ls, ms);
4029 break;
4030
4031 case DLM_MSG_CONVERT_REPLY:
4032 receive_convert_reply(ls, ms);
4033 break;
4034
4035 case DLM_MSG_UNLOCK_REPLY:
4036 receive_unlock_reply(ls, ms);
4037 break;
4038
4039 case DLM_MSG_CANCEL_REPLY:
4040 receive_cancel_reply(ls, ms);
4041 break;
4042
4043 /* messages sent from a master node (only two types of async msg) */
4044
4045 case DLM_MSG_GRANT:
4046 receive_grant(ls, ms);
4047 break;
4048
4049 case DLM_MSG_BAST:
4050 receive_bast(ls, ms);
4051 break;
4052
4053 /* messages sent to a dir node */
4054
4055 case DLM_MSG_LOOKUP:
4056 receive_lookup(ls, ms);
4057 break;
4058
4059 case DLM_MSG_REMOVE:
4060 receive_remove(ls, ms);
4061 break;
4062
4063 /* messages sent from a dir node (remove has no reply) */
4064
4065 case DLM_MSG_LOOKUP_REPLY:
4066 receive_lookup_reply(ls, ms);
4067 break;
4068
8499137d
DT		 4069 /* other messages */
4070
4071 case DLM_MSG_PURGE:
4072 receive_purge(ls, ms);
4073 break;
4074
e7fd4179
DT		 4075 default:
4076 log_error(ls, "unknown message type %d", ms->m_type);
4077 }
e7fd4179
DT		 4078}
4079
c36258b5
DT		 4080/* If the lockspace is in recovery mode (locking stopped), then normal
4081 messages are saved on the requestqueue for processing after recovery is
4082 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4083 messages off the requestqueue before we process new ones. This occurs right
4084 after recovery completes when we transition from saving all messages on
4085 requestqueue, to processing all the saved messages, to processing new
4086 messages as they arrive. */
e7fd4179 4087
c36258b5
DT		 4088static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4089 int nodeid)
4090{
4091 if (dlm_locking_stopped(ls)) {
8b0d8e03 4092 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 4093 } else {
4094 dlm_wait_requestqueue(ls);
4095 _receive_message(ls, ms);
4096 }
4097}
4098
4099/* This is called by dlm_recoverd to process messages that were saved on
4100 the requestqueue. */
4101
4102void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms)
4103{
4104 _receive_message(ls, ms);
4105}
4106
4107/* This is called by the midcomms layer when something is received for
4108 the lockspace. It could be either a MSG (normal message sent as part of
4109 standard locking activity) or an RCOM (recovery message sent as part of
4110 lockspace recovery). */
4111
eef7d739 4112void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 4113{
eef7d739 4114 struct dlm_header *hd = &p->header;
c36258b5
DT		 4115 struct dlm_ls *ls;
4116 int type = 0;
4117
4118 switch (hd->h_cmd) {
4119 case DLM_MSG:
eef7d739
AV		 4120 dlm_message_in(&p->message);
4121 type = p->message.m_type;
c36258b5
DT		 4122 break;
4123 case DLM_RCOM:
eef7d739
AV		 4124 dlm_rcom_in(&p->rcom);
4125 type = p->rcom.rc_type;
c36258b5
DT		 4126 break;
4127 default:
4128 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
4129 return;
4130 }
4131
4132 if (hd->h_nodeid != nodeid) {
4133 log_print("invalid h_nodeid %d from %d lockspace %x",
4134 hd->h_nodeid, nodeid, hd->h_lockspace);
4135 return;
4136 }
4137
4138 ls = dlm_find_lockspace_global(hd->h_lockspace);
4139 if (!ls) {
594199eb
DT		 4140 if (dlm_config.ci_log_debug)
4141 log_print("invalid lockspace %x from %d cmd %d type %d",
4142 hd->h_lockspace, nodeid, hd->h_cmd, type);
c36258b5
DT		 4143
4144 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 4145 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 4146 return;
4147 }
4148
4149 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
4150 be inactive (in this ls) before transitioning to recovery mode */
4151
4152 down_read(&ls->ls_recv_active);
4153 if (hd->h_cmd == DLM_MSG)
eef7d739 4154 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 4155 else
eef7d739 4156 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 4157 up_read(&ls->ls_recv_active);
4158
4159 dlm_put_lockspace(ls);
4160}
e7fd4179 4161
2a7ce0ed
DT		 4162static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
4163 struct dlm_message *ms_stub)
e7fd4179
DT		 4164{
4165 if (middle_conversion(lkb)) {
4166 hold_lkb(lkb);
2a7ce0ed
DT		 4167 memset(ms_stub, 0, sizeof(struct dlm_message));
4168 ms_stub->m_flags = DLM_IFL_STUB_MS;
4169 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
4170 ms_stub->m_result = -EINPROGRESS;
4171 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4172 _receive_convert_reply(lkb, ms_stub);
e7fd4179
DT		 4173
4174 /* Same special case as in receive_rcom_lock_args() */
4175 lkb->lkb_grmode = DLM_LOCK_IV;
4176 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
4177 unhold_lkb(lkb);
4178
4179 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
4180 lkb->lkb_flags |= DLM_IFL_RESEND;
4181 }
4182
4183 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
4184 conversions are async; there's no reply from the remote master */
4185}
4186
4187/* A waiting lkb needs recovery if the master node has failed, or
4188 the master node is changing (only when no directory is used) */
4189
4190static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb)
4191{
4192 if (dlm_is_removed(ls, lkb->lkb_nodeid))
4193 return 1;
4194
4195 if (!dlm_no_directory(ls))
4196 return 0;
4197
4198 if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid)
4199 return 1;
4200
4201 return 0;
4202}
4203
4204/* Recovery for locks that are waiting for replies from nodes that are now
4205 gone. We can just complete unlocks and cancels by faking a reply from the
4206 dead node. Requests and up-conversions we flag to be resent after
4207 recovery. Down-conversions can just be completed with a fake reply like
4208 unlocks. Conversions between PR and CW need special attention. */
4209
4210void dlm_recover_waiters_pre(struct dlm_ls *ls)
4211{
4212 struct dlm_lkb *lkb, *safe;
2a7ce0ed 4213 struct dlm_message *ms_stub;
601342ce 4214 int wait_type, stub_unlock_result, stub_cancel_result;
e7fd4179 4215
a22ca480 4216 ms_stub = kmalloc(sizeof(struct dlm_message), GFP_KERNEL);
2a7ce0ed
DT		 4217 if (!ms_stub) {
4218 log_error(ls, "dlm_recover_waiters_pre no mem");
4219 return;
4220 }
4221
90135925 4222 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4223
4224 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
2a7ce0ed
DT		 4225
4226 /* exclude debug messages about unlocks because there can be so
4227 many and they aren't very interesting */
4228
4229 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
4230 log_debug(ls, "recover_waiter %x nodeid %d "
4231 "msg %d to %d", lkb->lkb_id, lkb->lkb_nodeid,
4232 lkb->lkb_wait_type, lkb->lkb_wait_nodeid);
4233 }
e7fd4179
DT		 4234
4235 /* all outstanding lookups, regardless of destination will be
4236 resent after recovery is done */
4237
4238 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
4239 lkb->lkb_flags |= DLM_IFL_RESEND;
4240 continue;
4241 }
4242
4243 if (!waiter_needs_recovery(ls, lkb))
4244 continue;
4245
601342ce
DT		 4246 wait_type = lkb->lkb_wait_type;
4247 stub_unlock_result = -DLM_EUNLOCK;
4248 stub_cancel_result = -DLM_ECANCEL;
4249
4250 /* Main reply may have been received leaving a zero wait_type,
4251 but a reply for the overlapping op may not have been
4252 received. In that case we need to fake the appropriate
4253 reply for the overlap op. */
4254
4255 if (!wait_type) {
4256 if (is_overlap_cancel(lkb)) {
4257 wait_type = DLM_MSG_CANCEL;
4258 if (lkb->lkb_grmode == DLM_LOCK_IV)
4259 stub_cancel_result = 0;
4260 }
4261 if (is_overlap_unlock(lkb)) {
4262 wait_type = DLM_MSG_UNLOCK;
4263 if (lkb->lkb_grmode == DLM_LOCK_IV)
4264 stub_unlock_result = -ENOENT;
4265 }
4266
4267 log_debug(ls, "rwpre overlap %x %x %d %d %d",
4268 lkb->lkb_id, lkb->lkb_flags, wait_type,
4269 stub_cancel_result, stub_unlock_result);
4270 }
4271
4272 switch (wait_type) {
e7fd4179
DT		 4273
4274 case DLM_MSG_REQUEST:
4275 lkb->lkb_flags |= DLM_IFL_RESEND;
4276 break;
4277
4278 case DLM_MSG_CONVERT:
2a7ce0ed 4279 recover_convert_waiter(ls, lkb, ms_stub);
e7fd4179
DT		 4280 break;
4281
4282 case DLM_MSG_UNLOCK:
4283 hold_lkb(lkb);
2a7ce0ed
DT		 4284 memset(ms_stub, 0, sizeof(struct dlm_message));
4285 ms_stub->m_flags = DLM_IFL_STUB_MS;
4286 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
4287 ms_stub->m_result = stub_unlock_result;
4288 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4289 _receive_unlock_reply(lkb, ms_stub);
b3f58d8f 4290 dlm_put_lkb(lkb);
e7fd4179
DT		 4291 break;
4292
4293 case DLM_MSG_CANCEL:
4294 hold_lkb(lkb);
2a7ce0ed
DT		 4295 memset(ms_stub, 0, sizeof(struct dlm_message));
4296 ms_stub->m_flags = DLM_IFL_STUB_MS;
4297 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
4298 ms_stub->m_result = stub_cancel_result;
4299 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
4300 _receive_cancel_reply(lkb, ms_stub);
b3f58d8f 4301 dlm_put_lkb(lkb);
e7fd4179
DT		 4302 break;
4303
4304 default:
601342ce
DT		 4305 log_error(ls, "invalid lkb wait_type %d %d",
4306 lkb->lkb_wait_type, wait_type);
e7fd4179 4307 }
81456807 4308 schedule();
e7fd4179 4309 }
90135925 4310 mutex_unlock(&ls->ls_waiters_mutex);
2a7ce0ed 4311 kfree(ms_stub);
e7fd4179
DT		 4312}
4313
ef0c2bb0 4314static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 4315{
4316 struct dlm_lkb *lkb;
ef0c2bb0 4317 int found = 0;
e7fd4179 4318
90135925 4319 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 4320 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
4321 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 4322 hold_lkb(lkb);
4323 found = 1;
e7fd4179
DT		 4324 break;
4325 }
4326 }
90135925 4327 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 4328
ef0c2bb0 4329 if (!found)
e7fd4179 4330 lkb = NULL;
ef0c2bb0 4331 return lkb;
e7fd4179
DT		 4332}
4333
4334/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
4335 master or dir-node for r. Processing the lkb may result in it being placed
4336 back on waiters. */
4337
ef0c2bb0
DT		 4338/* We do this after normal locking has been enabled and any saved messages
4339 (in requestqueue) have been processed. We should be confident that at
4340 this point we won't get or process a reply to any of these waiting
4341 operations. But, new ops may be coming in on the rsbs/locks here from
4342 userspace or remotely. */
4343
4344/* there may have been an overlap unlock/cancel prior to recovery or after
4345 recovery. if before, the lkb may still have a pos wait_count; if after, the
4346 overlap flag would just have been set and nothing new sent. we can be
4347 confident here than any replies to either the initial op or overlap ops
4348 prior to recovery have been received. */
4349
e7fd4179
DT		 4350int dlm_recover_waiters_post(struct dlm_ls *ls)
4351{
4352 struct dlm_lkb *lkb;
4353 struct dlm_rsb *r;
ef0c2bb0 4354 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 4355
4356 while (1) {
4357 if (dlm_locking_stopped(ls)) {
4358 log_debug(ls, "recover_waiters_post aborted");
4359 error = -EINTR;
4360 break;
4361 }
4362
ef0c2bb0
DT		 4363 lkb = find_resend_waiter(ls);
4364 if (!lkb)
e7fd4179
DT		 4365 break;
4366
4367 r = lkb->lkb_resource;
ef0c2bb0
DT		 4368 hold_rsb(r);
4369 lock_rsb(r);
4370
4371 mstype = lkb->lkb_wait_type;
4372 oc = is_overlap_cancel(lkb);
4373 ou = is_overlap_unlock(lkb);
4374 err = 0;
e7fd4179 4375
2a7ce0ed
DT		 4376 log_debug(ls, "recover_waiter %x nodeid %d msg %d r_nodeid %d",
4377 lkb->lkb_id, lkb->lkb_nodeid, mstype, r->res_nodeid);
e7fd4179 4378
ef0c2bb0
DT		 4379 /* At this point we assume that we won't get a reply to any
4380 previous op or overlap op on this lock. First, do a big
4381 remove_from_waiters() for all previous ops. */
4382
4383 lkb->lkb_flags &= ~DLM_IFL_RESEND;
4384 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4385 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4386 lkb->lkb_wait_type = 0;
4387 lkb->lkb_wait_count = 0;
4388 mutex_lock(&ls->ls_waiters_mutex);
4389 list_del_init(&lkb->lkb_wait_reply);
4390 mutex_unlock(&ls->ls_waiters_mutex);
4391 unhold_lkb(lkb); /* for waiters list */
4392
4393 if (oc || ou) {
4394 /* do an unlock or cancel instead of resending */
4395 switch (mstype) {
4396 case DLM_MSG_LOOKUP:
4397 case DLM_MSG_REQUEST:
4398 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
4399 -DLM_ECANCEL);
4400 unhold_lkb(lkb); /* undoes create_lkb() */
4401 break;
4402 case DLM_MSG_CONVERT:
4403 if (oc) {
4404 queue_cast(r, lkb, -DLM_ECANCEL);
4405 } else {
4406 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
4407 _unlock_lock(r, lkb);
4408 }
4409 break;
4410 default:
4411 err = 1;
4412 }
4413 } else {
4414 switch (mstype) {
4415 case DLM_MSG_LOOKUP:
4416 case DLM_MSG_REQUEST:
4417 _request_lock(r, lkb);
4418 if (is_master(r))
4419 confirm_master(r, 0);
4420 break;
4421 case DLM_MSG_CONVERT:
4422 _convert_lock(r, lkb);
4423 break;
4424 default:
4425 err = 1;
4426 }
e7fd4179 4427 }
ef0c2bb0
DT		 4428
4429 if (err)
4430 log_error(ls, "recover_waiters_post %x %d %x %d %d",
4431 lkb->lkb_id, mstype, lkb->lkb_flags, oc, ou);
4432 unlock_rsb(r);
4433 put_rsb(r);
4434 dlm_put_lkb(lkb);
e7fd4179
DT		 4435 }
4436
4437 return error;
4438}
4439
4440static void purge_queue(struct dlm_rsb *r, struct list_head *queue,
4441 int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb))
4442{
4443 struct dlm_ls *ls = r->res_ls;
4444 struct dlm_lkb *lkb, *safe;
4445
4446 list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) {
4447 if (test(ls, lkb)) {
97a35d1e 4448 rsb_set_flag(r, RSB_LOCKS_PURGED);
e7fd4179
DT		 4449 del_lkb(r, lkb);
4450 /* this put should free the lkb */
b3f58d8f 4451 if (!dlm_put_lkb(lkb))
e7fd4179
DT		 4452 log_error(ls, "purged lkb not released");
4453 }
4454 }
4455}
4456
4457static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4458{
4459 return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid));
4460}
4461
4462static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb)
4463{
4464 return is_master_copy(lkb);
4465}
4466
4467static void purge_dead_locks(struct dlm_rsb *r)
4468{
4469 purge_queue(r, &r->res_grantqueue, &purge_dead_test);
4470 purge_queue(r, &r->res_convertqueue, &purge_dead_test);
4471 purge_queue(r, &r->res_waitqueue, &purge_dead_test);
4472}
4473
4474void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
4475{
4476 purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test);
4477 purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test);
4478 purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test);
4479}
4480
4481/* Get rid of locks held by nodes that are gone. */
4482
4483int dlm_purge_locks(struct dlm_ls *ls)
4484{
4485 struct dlm_rsb *r;
4486
4487 log_debug(ls, "dlm_purge_locks");
4488
4489 down_write(&ls->ls_root_sem);
4490 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
4491 hold_rsb(r);
4492 lock_rsb(r);
4493 if (is_master(r))
4494 purge_dead_locks(r);
4495 unlock_rsb(r);
4496 unhold_rsb(r);
4497
4498 schedule();
4499 }
4500 up_write(&ls->ls_root_sem);
4501
4502 return 0;
4503}
4504
97a35d1e
DT		 4505static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
4506{
9beb3bf5 4507 struct rb_node *n;
97a35d1e
DT		 4508 struct dlm_rsb *r, *r_ret = NULL;
4509
c7be761a 4510 spin_lock(&ls->ls_rsbtbl[bucket].lock);
9beb3bf5
BP		 4511 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
4512 r = rb_entry(n, struct dlm_rsb, res_hashnode);
97a35d1e
DT		 4513 if (!rsb_flag(r, RSB_LOCKS_PURGED))
4514 continue;
4515 hold_rsb(r);
4516 rsb_clear_flag(r, RSB_LOCKS_PURGED);
4517 r_ret = r;
4518 break;
4519 }
c7be761a 4520 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
97a35d1e
DT		 4521 return r_ret;
4522}
4523
4524void dlm_grant_after_purge(struct dlm_ls *ls)
e7fd4179
DT		 4525{
4526 struct dlm_rsb *r;
2b4e926a 4527 int bucket = 0;
e7fd4179 4528
2b4e926a
DT		 4529 while (1) {
4530 r = find_purged_rsb(ls, bucket);
4531 if (!r) {
4532 if (bucket == ls->ls_rsbtbl_size - 1)
4533 break;
4534 bucket++;
97a35d1e 4535 continue;
2b4e926a 4536 }
97a35d1e
DT		 4537 lock_rsb(r);
4538 if (is_master(r)) {
4539 grant_pending_locks(r);
4540 confirm_master(r, 0);
e7fd4179 4541 }
97a35d1e
DT		 4542 unlock_rsb(r);
4543 put_rsb(r);
2b4e926a 4544 schedule();
e7fd4179 4545 }
e7fd4179
DT		 4546}
4547
4548static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
4549 uint32_t remid)
4550{
4551 struct dlm_lkb *lkb;
4552
4553 list_for_each_entry(lkb, head, lkb_statequeue) {
4554 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
4555 return lkb;
4556 }
4557 return NULL;
4558}
4559
4560static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
4561 uint32_t remid)
4562{
4563 struct dlm_lkb *lkb;
4564
4565 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
4566 if (lkb)
4567 return lkb;
4568 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
4569 if (lkb)
4570 return lkb;
4571 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
4572 if (lkb)
4573 return lkb;
4574 return NULL;
4575}
4576
ae773d0b 4577/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4578static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
4579 struct dlm_rsb *r, struct dlm_rcom *rc)
4580{
4581 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 4582
4583 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 4584 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
4585 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
4586 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
4587 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 4588 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 4589 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 4590 lkb->lkb_rqmode = rl->rl_rqmode;
4591 lkb->lkb_grmode = rl->rl_grmode;
4592 /* don't set lkb_status because add_lkb wants to itself */
4593
8304d6f2
DT		 4594 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
4595 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 4596
e7fd4179 4597 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 4598 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
4599 sizeof(struct rcom_lock);
4600 if (lvblen > ls->ls_lvblen)
4601 return -EINVAL;
52bda2b5 4602 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 4603 if (!lkb->lkb_lvbptr)
4604 return -ENOMEM;
e7fd4179
DT		 4605 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
4606 }
4607
4608 /* Conversions between PR and CW (middle modes) need special handling.
4609 The real granted mode of these converting locks cannot be determined
4610 until all locks have been rebuilt on the rsb (recover_conversion) */
4611
163a1859
AV		 4612 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
4613 middle_conversion(lkb)) {
e7fd4179
DT		 4614 rl->rl_status = DLM_LKSTS_CONVERT;
4615 lkb->lkb_grmode = DLM_LOCK_IV;
4616 rsb_set_flag(r, RSB_RECOVER_CONVERT);
4617 }
4618
4619 return 0;
4620}
4621
4622/* This lkb may have been recovered in a previous aborted recovery so we need
4623 to check if the rsb already has an lkb with the given remote nodeid/lkid.
4624 If so we just send back a standard reply. If not, we create a new lkb with
4625 the given values and send back our lkid. We send back our lkid by sending
4626 back the rcom_lock struct we got but with the remid field filled in. */
4627
ae773d0b 4628/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4629int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4630{
4631 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4632 struct dlm_rsb *r;
4633 struct dlm_lkb *lkb;
4634 int error;
4635
4636 if (rl->rl_parent_lkid) {
4637 error = -EOPNOTSUPP;
4638 goto out;
4639 }
4640
163a1859
AV		 4641 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
4642 R_MASTER, &r);
e7fd4179
DT		 4643 if (error)
4644 goto out;
4645
4646 lock_rsb(r);
4647
163a1859 4648 lkb = search_remid(r, rc->rc_header.h_nodeid, le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4649 if (lkb) {
4650 error = -EEXIST;
4651 goto out_remid;
4652 }
4653
4654 error = create_lkb(ls, &lkb);
4655 if (error)
4656 goto out_unlock;
4657
4658 error = receive_rcom_lock_args(ls, lkb, r, rc);
4659 if (error) {
b3f58d8f 4660 __put_lkb(ls, lkb);
e7fd4179
DT		 4661 goto out_unlock;
4662 }
4663
4664 attach_lkb(r, lkb);
4665 add_lkb(r, lkb, rl->rl_status);
4666 error = 0;
4667
4668 out_remid:
4669 /* this is the new value returned to the lock holder for
4670 saving in its process-copy lkb */
163a1859 4671 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179
DT		 4672
4673 out_unlock:
4674 unlock_rsb(r);
4675 put_rsb(r);
4676 out:
4677 if (error)
163a1859
AV		 4678 log_debug(ls, "recover_master_copy %d %x", error,
4679 le32_to_cpu(rl->rl_lkid));
4680 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 4681 return error;
4682}
4683
ae773d0b 4684/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 4685int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
4686{
4687 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
4688 struct dlm_rsb *r;
4689 struct dlm_lkb *lkb;
4690 int error;
4691
163a1859 4692 error = find_lkb(ls, le32_to_cpu(rl->rl_lkid), &lkb);
e7fd4179 4693 if (error) {
163a1859
AV		 4694 log_error(ls, "recover_process_copy no lkid %x",
4695 le32_to_cpu(rl->rl_lkid));
e7fd4179
DT		 4696 return error;
4697 }
4698
4699 DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
4700
163a1859 4701 error = le32_to_cpu(rl->rl_result);
e7fd4179
DT		 4702
4703 r = lkb->lkb_resource;
4704 hold_rsb(r);
4705 lock_rsb(r);
4706
4707 switch (error) {
dc200a88
DT		 4708 case -EBADR:
4709 /* There's a chance the new master received our lock before
4710 dlm_recover_master_reply(), this wouldn't happen if we did
4711 a barrier between recover_masters and recover_locks. */
4712 log_debug(ls, "master copy not ready %x r %lx %s", lkb->lkb_id,
4713 (unsigned long)r, r->res_name);
4714 dlm_send_rcom_lock(r, lkb);
4715 goto out;
e7fd4179
DT		 4716 case -EEXIST:
4717 log_debug(ls, "master copy exists %x", lkb->lkb_id);
4718 /* fall through */
4719 case 0:
163a1859 4720 lkb->lkb_remid = le32_to_cpu(rl->rl_remid);
e7fd4179
DT		 4721 break;
4722 default:
4723 log_error(ls, "dlm_recover_process_copy unknown error %d %x",
4724 error, lkb->lkb_id);
4725 }
4726
4727 /* an ack for dlm_recover_locks() which waits for replies from
4728 all the locks it sends to new masters */
4729 dlm_recovered_lock(r);
dc200a88 4730 out:
e7fd4179
DT		 4731 unlock_rsb(r);
4732 put_rsb(r);
b3f58d8f 4733 dlm_put_lkb(lkb);
e7fd4179
DT		 4734
4735 return 0;
4736}
4737
597d0cae
DT		 4738int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
4739 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 4740 unsigned long timeout_cs)
597d0cae
DT		 4741{
4742 struct dlm_lkb *lkb;
4743 struct dlm_args args;
4744 int error;
4745
85e86edf 4746 dlm_lock_recovery(ls);
597d0cae
DT		 4747
4748 error = create_lkb(ls, &lkb);
4749 if (error) {
4750 kfree(ua);
4751 goto out;
4752 }
4753
4754 if (flags & DLM_LKF_VALBLK) {
573c24c4 4755 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 4756 if (!ua->lksb.sb_lvbptr) {
4757 kfree(ua);
4758 __put_lkb(ls, lkb);
4759 error = -ENOMEM;
4760 goto out;
4761 }
4762 }
4763
52bda2b5 4764 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 4765 When DLM_IFL_USER is set, the dlm knows that this is a userspace
4766 lock and that lkb_astparam is the dlm_user_args structure. */
4767
d7db923e 4768 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 4769 fake_astfn, ua, fake_bastfn, &args);
597d0cae 4770 lkb->lkb_flags |= DLM_IFL_USER;
597d0cae
DT		 4771
4772 if (error) {
4773 __put_lkb(ls, lkb);
4774 goto out;
4775 }
4776
4777 error = request_lock(ls, lkb, name, namelen, &args);
4778
4779 switch (error) {
4780 case 0:
4781 break;
4782 case -EINPROGRESS:
4783 error = 0;
4784 break;
4785 case -EAGAIN:
4786 error = 0;
4787 /* fall through */
4788 default:
4789 __put_lkb(ls, lkb);
4790 goto out;
4791 }
4792
4793 /* add this new lkb to the per-process list of locks */
4794 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 4795 hold_lkb(lkb);
597d0cae
DT		 4796 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
4797 spin_unlock(&ua->proc->locks_spin);
4798 out:
85e86edf 4799 dlm_unlock_recovery(ls);
597d0cae
DT		 4800 return error;
4801}
4802
4803int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 4804 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
4805 unsigned long timeout_cs)
597d0cae
DT		 4806{
4807 struct dlm_lkb *lkb;
4808 struct dlm_args args;
4809 struct dlm_user_args *ua;
4810 int error;
4811
85e86edf 4812 dlm_lock_recovery(ls);
597d0cae
DT		 4813
4814 error = find_lkb(ls, lkid, &lkb);
4815 if (error)
4816 goto out;
4817
4818 /* user can change the params on its lock when it converts it, or
4819 add an lvb that didn't exist before */
4820
d292c0cc 4821 ua = lkb->lkb_ua;
597d0cae
DT		 4822
4823 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
573c24c4 4824 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 4825 if (!ua->lksb.sb_lvbptr) {
4826 error = -ENOMEM;
4827 goto out_put;
4828 }
4829 }
4830 if (lvb_in && ua->lksb.sb_lvbptr)
4831 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
4832
d7db923e 4833 ua->xid = ua_tmp->xid;
597d0cae
DT		 4834 ua->castparam = ua_tmp->castparam;
4835 ua->castaddr = ua_tmp->castaddr;
4836 ua->bastparam = ua_tmp->bastparam;
4837 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 4838 ua->user_lksb = ua_tmp->user_lksb;
597d0cae 4839
d7db923e 4840 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 4841 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 4842 if (error)
4843 goto out_put;
4844
4845 error = convert_lock(ls, lkb, &args);
4846
c85d65e9 4847 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 4848 error = 0;
4849 out_put:
4850 dlm_put_lkb(lkb);
4851 out:
85e86edf 4852 dlm_unlock_recovery(ls);
597d0cae
DT		 4853 kfree(ua_tmp);
4854 return error;
4855}
4856
4857int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4858 uint32_t flags, uint32_t lkid, char *lvb_in)
4859{
4860 struct dlm_lkb *lkb;
4861 struct dlm_args args;
4862 struct dlm_user_args *ua;
4863 int error;
4864
85e86edf 4865 dlm_lock_recovery(ls);
597d0cae
DT		 4866
4867 error = find_lkb(ls, lkid, &lkb);
4868 if (error)
4869 goto out;
4870
d292c0cc 4871 ua = lkb->lkb_ua;
597d0cae
DT		 4872
4873 if (lvb_in && ua->lksb.sb_lvbptr)
4874 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 4875 if (ua_tmp->castparam)
4876 ua->castparam = ua_tmp->castparam;
cc346d55 4877 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4878
4879 error = set_unlock_args(flags, ua, &args);
4880 if (error)
4881 goto out_put;
4882
4883 error = unlock_lock(ls, lkb, &args);
4884
4885 if (error == -DLM_EUNLOCK)
4886 error = 0;
ef0c2bb0
DT		 4887 /* from validate_unlock_args() */
4888 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
4889 error = 0;
597d0cae
DT		 4890 if (error)
4891 goto out_put;
4892
4893 spin_lock(&ua->proc->locks_spin);
23e8e1aa 4894 /* dlm_user_add_cb() may have already taken lkb off the proc list */
a1bc86e6
DT		 4895 if (!list_empty(&lkb->lkb_ownqueue))
4896 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 4897 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 4898 out_put:
4899 dlm_put_lkb(lkb);
4900 out:
85e86edf 4901 dlm_unlock_recovery(ls);
ef0c2bb0 4902 kfree(ua_tmp);
597d0cae
DT		 4903 return error;
4904}
4905
4906int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
4907 uint32_t flags, uint32_t lkid)
4908{
4909 struct dlm_lkb *lkb;
4910 struct dlm_args args;
4911 struct dlm_user_args *ua;
4912 int error;
4913
85e86edf 4914 dlm_lock_recovery(ls);
597d0cae
DT		 4915
4916 error = find_lkb(ls, lkid, &lkb);
4917 if (error)
4918 goto out;
4919
d292c0cc 4920 ua = lkb->lkb_ua;
b434eda6
PC		 4921 if (ua_tmp->castparam)
4922 ua->castparam = ua_tmp->castparam;
c059f70e 4923 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 4924
4925 error = set_unlock_args(flags, ua, &args);
4926 if (error)
4927 goto out_put;
4928
4929 error = cancel_lock(ls, lkb, &args);
4930
4931 if (error == -DLM_ECANCEL)
4932 error = 0;
ef0c2bb0
DT		 4933 /* from validate_unlock_args() */
4934 if (error == -EBUSY)
4935 error = 0;
597d0cae
DT		 4936 out_put:
4937 dlm_put_lkb(lkb);
4938 out:
85e86edf 4939 dlm_unlock_recovery(ls);
ef0c2bb0 4940 kfree(ua_tmp);
597d0cae
DT		 4941 return error;
4942}
4943
8b4021fa
DT		 4944int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
4945{
4946 struct dlm_lkb *lkb;
4947 struct dlm_args args;
4948 struct dlm_user_args *ua;
4949 struct dlm_rsb *r;
4950 int error;
4951
4952 dlm_lock_recovery(ls);
4953
4954 error = find_lkb(ls, lkid, &lkb);
4955 if (error)
4956 goto out;
4957
d292c0cc 4958 ua = lkb->lkb_ua;
8b4021fa
DT		 4959
4960 error = set_unlock_args(flags, ua, &args);
4961 if (error)
4962 goto out_put;
4963
4964 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
4965
4966 r = lkb->lkb_resource;
4967 hold_rsb(r);
4968 lock_rsb(r);
4969
4970 error = validate_unlock_args(lkb, &args);
4971 if (error)
4972 goto out_r;
4973 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
4974
4975 error = _cancel_lock(r, lkb);
4976 out_r:
4977 unlock_rsb(r);
4978 put_rsb(r);
4979
4980 if (error == -DLM_ECANCEL)
4981 error = 0;
4982 /* from validate_unlock_args() */
4983 if (error == -EBUSY)
4984 error = 0;
4985 out_put:
4986 dlm_put_lkb(lkb);
4987 out:
4988 dlm_unlock_recovery(ls);
4989 return error;
4990}
4991
ef0c2bb0
DT		 4992/* lkb's that are removed from the waiters list by revert are just left on the
4993 orphans list with the granted orphan locks, to be freed by purge */
4994
597d0cae
DT		 4995static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
4996{
ef0c2bb0
DT		 4997 struct dlm_args args;
4998 int error;
597d0cae 4999
ef0c2bb0
DT		 5000 hold_lkb(lkb);
5001 mutex_lock(&ls->ls_orphans_mutex);
5002 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
5003 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 5004
d292c0cc 5005 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 5006
5007 error = cancel_lock(ls, lkb, &args);
5008 if (error == -DLM_ECANCEL)
5009 error = 0;
5010 return error;
597d0cae
DT		 5011}
5012
5013/* The force flag allows the unlock to go ahead even if the lkb isn't granted.
5014 Regardless of what rsb queue the lock is on, it's removed and freed. */
5015
5016static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
5017{
597d0cae
DT		 5018 struct dlm_args args;
5019 int error;
5020
d292c0cc 5021 set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
597d0cae
DT		 5022
5023 error = unlock_lock(ls, lkb, &args);
5024 if (error == -DLM_EUNLOCK)
5025 error = 0;
5026 return error;
5027}
5028
ef0c2bb0
DT		 5029/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
5030 (which does lock_rsb) due to deadlock with receiving a message that does
23e8e1aa 5031 lock_rsb followed by dlm_user_add_cb() */
ef0c2bb0
DT		 5032
5033static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
5034 struct dlm_user_proc *proc)
5035{
5036 struct dlm_lkb *lkb = NULL;
5037
5038 mutex_lock(&ls->ls_clear_proc_locks);
5039 if (list_empty(&proc->locks))
5040 goto out;
5041
5042 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
5043 list_del_init(&lkb->lkb_ownqueue);
5044
5045 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
5046 lkb->lkb_flags |= DLM_IFL_ORPHAN;
5047 else
5048 lkb->lkb_flags |= DLM_IFL_DEAD;
5049 out:
5050 mutex_unlock(&ls->ls_clear_proc_locks);
5051 return lkb;
5052}
5053
23e8e1aa 5054/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
597d0cae
DT		 5055 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
5056 which we clear here. */
5057
5058/* proc CLOSING flag is set so no more device_reads should look at proc->asts
5059 list, and no more device_writes should add lkb's to proc->locks list; so we
5060 shouldn't need to take asts_spin or locks_spin here. this assumes that
5061 device reads/writes/closes are serialized -- FIXME: we may need to serialize
5062 them ourself. */
5063
5064void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
5065{
5066 struct dlm_lkb *lkb, *safe;
5067
85e86edf 5068 dlm_lock_recovery(ls);
597d0cae 5069
ef0c2bb0
DT		 5070 while (1) {
5071 lkb = del_proc_lock(ls, proc);
5072 if (!lkb)
5073 break;
84d8cd69 5074 del_timeout(lkb);
ef0c2bb0 5075 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 5076 orphan_proc_lock(ls, lkb);
ef0c2bb0 5077 else
597d0cae 5078 unlock_proc_lock(ls, lkb);
597d0cae
DT		 5079
5080 /* this removes the reference for the proc->locks list
5081 added by dlm_user_request, it may result in the lkb
5082 being freed */
5083
5084 dlm_put_lkb(lkb);
5085 }
a1bc86e6 5086
ef0c2bb0
DT		 5087 mutex_lock(&ls->ls_clear_proc_locks);
5088
a1bc86e6
DT		 5089 /* in-progress unlocks */
5090 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
5091 list_del_init(&lkb->lkb_ownqueue);
5092 lkb->lkb_flags |= DLM_IFL_DEAD;
5093 dlm_put_lkb(lkb);
5094 }
5095
23e8e1aa 5096 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 5097 memset(&lkb->lkb_callbacks, 0,
5098 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 5099 list_del_init(&lkb->lkb_cb_list);
a1bc86e6
DT		 5100 dlm_put_lkb(lkb);
5101 }
5102
597d0cae 5103 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 5104 dlm_unlock_recovery(ls);
597d0cae 5105}
a1bc86e6 5106
8499137d
DT		 5107static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
5108{
5109 struct dlm_lkb *lkb, *safe;
5110
5111 while (1) {
5112 lkb = NULL;
5113 spin_lock(&proc->locks_spin);
5114 if (!list_empty(&proc->locks)) {
5115 lkb = list_entry(proc->locks.next, struct dlm_lkb,
5116 lkb_ownqueue);
5117 list_del_init(&lkb->lkb_ownqueue);
5118 }
5119 spin_unlock(&proc->locks_spin);
5120
5121 if (!lkb)
5122 break;
5123
5124 lkb->lkb_flags |= DLM_IFL_DEAD;
5125 unlock_proc_lock(ls, lkb);
5126 dlm_put_lkb(lkb); /* ref from proc->locks list */
5127 }
5128
5129 spin_lock(&proc->locks_spin);
5130 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
5131 list_del_init(&lkb->lkb_ownqueue);
5132 lkb->lkb_flags |= DLM_IFL_DEAD;
5133 dlm_put_lkb(lkb);
5134 }
5135 spin_unlock(&proc->locks_spin);
5136
5137 spin_lock(&proc->asts_spin);
23e8e1aa 5138 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 5139 memset(&lkb->lkb_callbacks, 0,
5140 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 5141 list_del_init(&lkb->lkb_cb_list);
8499137d
DT		 5142 dlm_put_lkb(lkb);
5143 }
5144 spin_unlock(&proc->asts_spin);
5145}
5146
5147/* pid of 0 means purge all orphans */
5148
5149static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
5150{
5151 struct dlm_lkb *lkb, *safe;
5152
5153 mutex_lock(&ls->ls_orphans_mutex);
5154 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
5155 if (pid && lkb->lkb_ownpid != pid)
5156 continue;
5157 unlock_proc_lock(ls, lkb);
5158 list_del_init(&lkb->lkb_ownqueue);
5159 dlm_put_lkb(lkb);
5160 }
5161 mutex_unlock(&ls->ls_orphans_mutex);
5162}
5163
5164static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
5165{
5166 struct dlm_message *ms;
5167 struct dlm_mhandle *mh;
5168 int error;
5169
5170 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
5171 DLM_MSG_PURGE, &ms, &mh);
5172 if (error)
5173 return error;
5174 ms->m_nodeid = nodeid;
5175 ms->m_pid = pid;
5176
5177 return send_message(mh, ms);
5178}
5179
5180int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
5181 int nodeid, int pid)
5182{
5183 int error = 0;
5184
5185 if (nodeid != dlm_our_nodeid()) {
5186 error = send_purge(ls, nodeid, pid);
5187 } else {
85e86edf 5188 dlm_lock_recovery(ls);
8499137d
DT		 5189 if (pid == current->pid)
5190 purge_proc_locks(ls, proc);
5191 else
5192 do_purge(ls, nodeid, pid);
85e86edf 5193 dlm_unlock_recovery(ls);
8499137d
DT		 5194 }
5195 return error;
5196}
5197
Linux kernel - Deliverables
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