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afs: Use d_instantiate() rather than d_add() and don't d_drop()
[linux.git] / fs / dlm / lock.c
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e7fd4179
DT		 1/******************************************************************************
2*******************************************************************************
3**
7fe2b319 4** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
e7fd4179
DT		 5**
6** This copyrighted material is made available to anyone wishing to use,
7** modify, copy, or redistribute it subject to the terms and conditions
8** of the GNU General Public License v.2.
9**
10*******************************************************************************
11******************************************************************************/
12
13/* Central locking logic has four stages:
14
15 dlm_lock()
16 dlm_unlock()
17
18 request_lock(ls, lkb)
19 convert_lock(ls, lkb)
20 unlock_lock(ls, lkb)
21 cancel_lock(ls, lkb)
22
23 _request_lock(r, lkb)
24 _convert_lock(r, lkb)
25 _unlock_lock(r, lkb)
26 _cancel_lock(r, lkb)
27
28 do_request(r, lkb)
29 do_convert(r, lkb)
30 do_unlock(r, lkb)
31 do_cancel(r, lkb)
32
33 Stage 1 (lock, unlock) is mainly about checking input args and
34 splitting into one of the four main operations:
35
36 dlm_lock = request_lock
37 dlm_lock+CONVERT = convert_lock
38 dlm_unlock = unlock_lock
39 dlm_unlock+CANCEL = cancel_lock
40
41 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
42 provided to the next stage.
43
44 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
45 When remote, it calls send_xxxx(), when local it calls do_xxxx().
46
47 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
48 given rsb and lkb and queues callbacks.
49
50 For remote operations, send_xxxx() results in the corresponding do_xxxx()
51 function being executed on the remote node. The connecting send/receive
52 calls on local (L) and remote (R) nodes:
53
54 L: send_xxxx() -> R: receive_xxxx()
55 R: do_xxxx()
56 L: receive_xxxx_reply() <- R: send_xxxx_reply()
57*/
597d0cae 58#include <linux/types.h>
9beb3bf5 59#include <linux/rbtree.h>
5a0e3ad6 60#include <linux/slab.h>
e7fd4179 61#include "dlm_internal.h"
597d0cae 62#include <linux/dlm_device.h>
e7fd4179
DT		 63#include "memory.h"
64#include "lowcomms.h"
65#include "requestqueue.h"
66#include "util.h"
67#include "dir.h"
68#include "member.h"
69#include "lockspace.h"
70#include "ast.h"
71#include "lock.h"
72#include "rcom.h"
73#include "recover.h"
74#include "lvb_table.h"
597d0cae 75#include "user.h"
e7fd4179
DT		 76#include "config.h"
77
78static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
82static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
83static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
84static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
85static int send_remove(struct dlm_rsb *r);
86static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
3ae1acf9 87static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
e7fd4179
DT		 88static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
89 struct dlm_message *ms);
90static int receive_extralen(struct dlm_message *ms);
8499137d 91static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
3ae1acf9 92static void del_timeout(struct dlm_lkb *lkb);
c04fecb4 93static void toss_rsb(struct kref *kref);
e7fd4179
DT		 94
95/*
96 * Lock compatibilty matrix - thanks Steve
97 * UN = Unlocked state. Not really a state, used as a flag
98 * PD = Padding. Used to make the matrix a nice power of two in size
99 * Other states are the same as the VMS DLM.
100 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
101 */
102
103static const int __dlm_compat_matrix[8][8] = {
104 /* UN NL CR CW PR PW EX PD */
105 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
106 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
107 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
108 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
109 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
110 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
111 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
112 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
113};
114
115/*
116 * This defines the direction of transfer of LVB data.
117 * Granted mode is the row; requested mode is the column.
118 * Usage: matrix[grmode+1][rqmode+1]
119 * 1 = LVB is returned to the caller
120 * 0 = LVB is written to the resource
121 * -1 = nothing happens to the LVB
122 */
123
124const int dlm_lvb_operations[8][8] = {
125 /* UN NL CR CW PR PW EX PD*/
126 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
127 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
128 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
129 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
130 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
131 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
132 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
133 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
134};
e7fd4179
DT		 135
136#define modes_compat(gr, rq) \
137 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
138
139int dlm_modes_compat(int mode1, int mode2)
140{
141 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
142}
143
144/*
145 * Compatibility matrix for conversions with QUECVT set.
146 * Granted mode is the row; requested mode is the column.
147 * Usage: matrix[grmode+1][rqmode+1]
148 */
149
150static const int __quecvt_compat_matrix[8][8] = {
151 /* UN NL CR CW PR PW EX PD */
152 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
153 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
154 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
155 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
156 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
157 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
158 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
159 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
160};
161
597d0cae 162void dlm_print_lkb(struct dlm_lkb *lkb)
e7fd4179 163{
6d40c4a7 164 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
4875647a 165 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
e7fd4179
DT		 166 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
167 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
4875647a
DT		 168 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
169 (unsigned long long)lkb->lkb_recover_seq);
e7fd4179
DT		 170}
171
170e19ab 172static void dlm_print_rsb(struct dlm_rsb *r)
e7fd4179 173{
c04fecb4
DT		 174 printk(KERN_ERR "rsb: nodeid %d master %d dir %d flags %lx first %x "
175 "rlc %d name %s\n",
176 r->res_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
177 r->res_flags, r->res_first_lkid, r->res_recover_locks_count,
178 r->res_name);
e7fd4179
DT		 179}
180
a345da3e
DT		 181void dlm_dump_rsb(struct dlm_rsb *r)
182{
183 struct dlm_lkb *lkb;
184
185 dlm_print_rsb(r);
186
187 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
188 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
189 printk(KERN_ERR "rsb lookup list\n");
190 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
191 dlm_print_lkb(lkb);
192 printk(KERN_ERR "rsb grant queue:\n");
193 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
194 dlm_print_lkb(lkb);
195 printk(KERN_ERR "rsb convert queue:\n");
196 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
197 dlm_print_lkb(lkb);
198 printk(KERN_ERR "rsb wait queue:\n");
199 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
200 dlm_print_lkb(lkb);
201}
202
e7fd4179
DT		 203/* Threads cannot use the lockspace while it's being recovered */
204
85e86edf 205static inline void dlm_lock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 206{
207 down_read(&ls->ls_in_recovery);
208}
209
85e86edf 210void dlm_unlock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 211{
212 up_read(&ls->ls_in_recovery);
213}
214
85e86edf 215int dlm_lock_recovery_try(struct dlm_ls *ls)
e7fd4179
DT		 216{
217 return down_read_trylock(&ls->ls_in_recovery);
218}
219
220static inline int can_be_queued(struct dlm_lkb *lkb)
221{
222 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
223}
224
225static inline int force_blocking_asts(struct dlm_lkb *lkb)
226{
227 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
228}
229
230static inline int is_demoted(struct dlm_lkb *lkb)
231{
232 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
233}
234
7d3c1feb
DT		 235static inline int is_altmode(struct dlm_lkb *lkb)
236{
237 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
238}
239
240static inline int is_granted(struct dlm_lkb *lkb)
241{
242 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
243}
244
e7fd4179
DT		 245static inline int is_remote(struct dlm_rsb *r)
246{
247 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
248 return !!r->res_nodeid;
249}
250
251static inline int is_process_copy(struct dlm_lkb *lkb)
252{
253 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
254}
255
256static inline int is_master_copy(struct dlm_lkb *lkb)
257{
90135925 258 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
e7fd4179
DT		 259}
260
261static inline int middle_conversion(struct dlm_lkb *lkb)
262{
263 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
264 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
90135925
DT		 265 return 1;
266 return 0;
e7fd4179
DT		 267}
268
269static inline int down_conversion(struct dlm_lkb *lkb)
270{
271 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
272}
273
ef0c2bb0
DT		 274static inline int is_overlap_unlock(struct dlm_lkb *lkb)
275{
276 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
277}
278
279static inline int is_overlap_cancel(struct dlm_lkb *lkb)
280{
281 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
282}
283
284static inline int is_overlap(struct dlm_lkb *lkb)
285{
286 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
287 DLM_IFL_OVERLAP_CANCEL));
288}
289
e7fd4179
DT		 290static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
291{
292 if (is_master_copy(lkb))
293 return;
294
3ae1acf9
DT		 295 del_timeout(lkb);
296
e7fd4179
DT		 297 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
298
3ae1acf9
DT		 299 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
300 timeout caused the cancel then return -ETIMEDOUT */
301 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
302 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
303 rv = -ETIMEDOUT;
304 }
305
8b4021fa
DT		 306 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
307 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
308 rv = -EDEADLK;
309 }
310
23e8e1aa 311 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
e7fd4179
DT		 312}
313
ef0c2bb0
DT		 314static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
315{
316 queue_cast(r, lkb,
317 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
318}
319
e7fd4179
DT		 320static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
321{
b6fa8796 322 if (is_master_copy(lkb)) {
e7fd4179 323 send_bast(r, lkb, rqmode);
b6fa8796 324 } else {
23e8e1aa 325 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
b6fa8796 326 }
e7fd4179
DT		 327}
328
329/*
330 * Basic operations on rsb's and lkb's
331 */
332
c04fecb4
DT		 333/* This is only called to add a reference when the code already holds
334 a valid reference to the rsb, so there's no need for locking. */
335
336static inline void hold_rsb(struct dlm_rsb *r)
337{
338 kref_get(&r->res_ref);
339}
340
341void dlm_hold_rsb(struct dlm_rsb *r)
342{
343 hold_rsb(r);
344}
345
346/* When all references to the rsb are gone it's transferred to
347 the tossed list for later disposal. */
348
349static void put_rsb(struct dlm_rsb *r)
350{
351 struct dlm_ls *ls = r->res_ls;
352 uint32_t bucket = r->res_bucket;
353
354 spin_lock(&ls->ls_rsbtbl[bucket].lock);
355 kref_put(&r->res_ref, toss_rsb);
356 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
357}
358
359void dlm_put_rsb(struct dlm_rsb *r)
360{
361 put_rsb(r);
362}
363
3881ac04
DT		 364static int pre_rsb_struct(struct dlm_ls *ls)
365{
366 struct dlm_rsb *r1, *r2;
367 int count = 0;
368
369 spin_lock(&ls->ls_new_rsb_spin);
370 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
371 spin_unlock(&ls->ls_new_rsb_spin);
372 return 0;
373 }
374 spin_unlock(&ls->ls_new_rsb_spin);
375
376 r1 = dlm_allocate_rsb(ls);
377 r2 = dlm_allocate_rsb(ls);
378
379 spin_lock(&ls->ls_new_rsb_spin);
380 if (r1) {
381 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
382 ls->ls_new_rsb_count++;
383 }
384 if (r2) {
385 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
386 ls->ls_new_rsb_count++;
387 }
388 count = ls->ls_new_rsb_count;
389 spin_unlock(&ls->ls_new_rsb_spin);
390
391 if (!count)
392 return -ENOMEM;
393 return 0;
394}
395
396/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
397 unlock any spinlocks, go back and call pre_rsb_struct again.
398 Otherwise, take an rsb off the list and return it. */
399
400static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
401 struct dlm_rsb **r_ret)
e7fd4179
DT		 402{
403 struct dlm_rsb *r;
3881ac04
DT		 404 int count;
405
406 spin_lock(&ls->ls_new_rsb_spin);
407 if (list_empty(&ls->ls_new_rsb)) {
408 count = ls->ls_new_rsb_count;
409 spin_unlock(&ls->ls_new_rsb_spin);
410 log_debug(ls, "find_rsb retry %d %d %s",
411 count, dlm_config.ci_new_rsb_count, name);
412 return -EAGAIN;
413 }
e7fd4179 414
3881ac04
DT		 415 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
416 list_del(&r->res_hashchain);
9beb3bf5
BP		 417 /* Convert the empty list_head to a NULL rb_node for tree usage: */
418 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
3881ac04
DT		 419 ls->ls_new_rsb_count--;
420 spin_unlock(&ls->ls_new_rsb_spin);
e7fd4179
DT		 421
422 r->res_ls = ls;
423 r->res_length = len;
424 memcpy(r->res_name, name, len);
90135925 425 mutex_init(&r->res_mutex);
e7fd4179
DT		 426
427 INIT_LIST_HEAD(&r->res_lookup);
428 INIT_LIST_HEAD(&r->res_grantqueue);
429 INIT_LIST_HEAD(&r->res_convertqueue);
430 INIT_LIST_HEAD(&r->res_waitqueue);
431 INIT_LIST_HEAD(&r->res_root_list);
432 INIT_LIST_HEAD(&r->res_recover_list);
433
3881ac04
DT		 434 *r_ret = r;
435 return 0;
e7fd4179
DT		 436}
437
9beb3bf5
BP		 438static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
439{
440 char maxname[DLM_RESNAME_MAXLEN];
441
442 memset(maxname, 0, DLM_RESNAME_MAXLEN);
443 memcpy(maxname, name, nlen);
444 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
445}
446
7210cb7a 447int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
c04fecb4 448 struct dlm_rsb **r_ret)
e7fd4179 449{
9beb3bf5 450 struct rb_node *node = tree->rb_node;
e7fd4179 451 struct dlm_rsb *r;
9beb3bf5
BP		 452 int rc;
453
454 while (node) {
455 r = rb_entry(node, struct dlm_rsb, res_hashnode);
456 rc = rsb_cmp(r, name, len);
457 if (rc < 0)
458 node = node->rb_left;
459 else if (rc > 0)
460 node = node->rb_right;
461 else
e7fd4179
DT		 462 goto found;
463 }
18c60c0a 464 *r_ret = NULL;
597d0cae 465 return -EBADR;
e7fd4179
DT		 466
467 found:
e7fd4179 468 *r_ret = r;
c04fecb4 469 return 0;
e7fd4179
DT		 470}
471
9beb3bf5
BP		 472static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
473{
474 struct rb_node **newn = &tree->rb_node;
475 struct rb_node *parent = NULL;
476 int rc;
477
478 while (*newn) {
479 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
480 res_hashnode);
481
482 parent = *newn;
483 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
484 if (rc < 0)
485 newn = &parent->rb_left;
486 else if (rc > 0)
487 newn = &parent->rb_right;
488 else {
489 log_print("rsb_insert match");
490 dlm_dump_rsb(rsb);
491 dlm_dump_rsb(cur);
492 return -EEXIST;
493 }
494 }
495
496 rb_link_node(&rsb->res_hashnode, parent, newn);
497 rb_insert_color(&rsb->res_hashnode, tree);
498 return 0;
499}
500
c04fecb4
DT		 501/*
502 * Find rsb in rsbtbl and potentially create/add one
503 *
504 * Delaying the release of rsb's has a similar benefit to applications keeping
505 * NL locks on an rsb, but without the guarantee that the cached master value
506 * will still be valid when the rsb is reused. Apps aren't always smart enough
507 * to keep NL locks on an rsb that they may lock again shortly; this can lead
508 * to excessive master lookups and removals if we don't delay the release.
509 *
510 * Searching for an rsb means looking through both the normal list and toss
511 * list. When found on the toss list the rsb is moved to the normal list with
512 * ref count of 1; when found on normal list the ref count is incremented.
513 *
514 * rsb's on the keep list are being used locally and refcounted.
515 * rsb's on the toss list are not being used locally, and are not refcounted.
516 *
517 * The toss list rsb's were either
518 * - previously used locally but not any more (were on keep list, then
519 * moved to toss list when last refcount dropped)
520 * - created and put on toss list as a directory record for a lookup
521 * (we are the dir node for the res, but are not using the res right now,
522 * but some other node is)
523 *
524 * The purpose of find_rsb() is to return a refcounted rsb for local use.
525 * So, if the given rsb is on the toss list, it is moved to the keep list
526 * before being returned.
527 *
528 * toss_rsb() happens when all local usage of the rsb is done, i.e. no
529 * more refcounts exist, so the rsb is moved from the keep list to the
530 * toss list.
531 *
532 * rsb's on both keep and toss lists are used for doing a name to master
533 * lookups. rsb's that are in use locally (and being refcounted) are on
534 * the keep list, rsb's that are not in use locally (not refcounted) and
535 * only exist for name/master lookups are on the toss list.
536 *
537 * rsb's on the toss list who's dir_nodeid is not local can have stale
538 * name/master mappings. So, remote requests on such rsb's can potentially
539 * return with an error, which means the mapping is stale and needs to
540 * be updated with a new lookup. (The idea behind MASTER UNCERTAIN and
541 * first_lkid is to keep only a single outstanding request on an rsb
542 * while that rsb has a potentially stale master.)
543 */
544
545static int find_rsb_dir(struct dlm_ls *ls, char *name, int len,
546 uint32_t hash, uint32_t b,
547 int dir_nodeid, int from_nodeid,
548 unsigned int flags, struct dlm_rsb **r_ret)
e7fd4179 549{
c04fecb4
DT		 550 struct dlm_rsb *r = NULL;
551 int our_nodeid = dlm_our_nodeid();
552 int from_local = 0;
553 int from_other = 0;
554 int from_dir = 0;
555 int create = 0;
e7fd4179
DT		 556 int error;
557
c04fecb4
DT		 558 if (flags & R_RECEIVE_REQUEST) {
559 if (from_nodeid == dir_nodeid)
560 from_dir = 1;
561 else
562 from_other = 1;
563 } else if (flags & R_REQUEST) {
564 from_local = 1;
565 }
566
567 /*
568 * flags & R_RECEIVE_RECOVER is from dlm_recover_master_copy, so
569 * from_nodeid has sent us a lock in dlm_recover_locks, believing
570 * we're the new master. Our local recovery may not have set
571 * res_master_nodeid to our_nodeid yet, so allow either. Don't
572 * create the rsb; dlm_recover_process_copy() will handle EBADR
573 * by resending.
574 *
575 * If someone sends us a request, we are the dir node, and we do
576 * not find the rsb anywhere, then recreate it. This happens if
577 * someone sends us a request after we have removed/freed an rsb
578 * from our toss list. (They sent a request instead of lookup
579 * because they are using an rsb from their toss list.)
580 */
581
582 if (from_local || from_dir ||
583 (from_other && (dir_nodeid == our_nodeid))) {
584 create = 1;
e7fd4179 585 }
57638bf3 586
c04fecb4
DT		 587 retry:
588 if (create) {
589 error = pre_rsb_struct(ls);
590 if (error < 0)
591 goto out;
592 }
593
594 spin_lock(&ls->ls_rsbtbl[b].lock);
595
596 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
e7fd4179 597 if (error)
c04fecb4
DT		 598 goto do_toss;
599
600 /*
601 * rsb is active, so we can't check master_nodeid without lock_rsb.
602 */
e7fd4179 603
c04fecb4
DT		 604 kref_get(&r->res_ref);
605 error = 0;
606 goto out_unlock;
607
608
609 do_toss:
610 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
9beb3bf5 611 if (error)
c04fecb4 612 goto do_new;
e7fd4179 613
c04fecb4
DT		 614 /*
615 * rsb found inactive (master_nodeid may be out of date unless
616 * we are the dir_nodeid or were the master) No other thread
617 * is using this rsb because it's on the toss list, so we can
618 * look at or update res_master_nodeid without lock_rsb.
619 */
e7fd4179 620
c04fecb4
DT		 621 if ((r->res_master_nodeid != our_nodeid) && from_other) {
622 /* our rsb was not master, and another node (not the dir node)
623 has sent us a request */
624 log_debug(ls, "find_rsb toss from_other %d master %d dir %d %s",
625 from_nodeid, r->res_master_nodeid, dir_nodeid,
626 r->res_name);
627 error = -ENOTBLK;
628 goto out_unlock;
629 }
630
631 if ((r->res_master_nodeid != our_nodeid) && from_dir) {
632 /* don't think this should ever happen */
633 log_error(ls, "find_rsb toss from_dir %d master %d",
634 from_nodeid, r->res_master_nodeid);
635 dlm_print_rsb(r);
636 /* fix it and go on */
637 r->res_master_nodeid = our_nodeid;
638 r->res_nodeid = 0;
e7fd4179
DT		 639 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
640 r->res_first_lkid = 0;
c04fecb4
DT		 641 }
642
643 if (from_local && (r->res_master_nodeid != our_nodeid)) {
644 /* Because we have held no locks on this rsb,
645 res_master_nodeid could have become stale. */
e7fd4179
DT		 646 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
647 r->res_first_lkid = 0;
c04fecb4
DT		 648 }
649
650 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
651 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
652 goto out_unlock;
653
654
655 do_new:
656 /*
657 * rsb not found
658 */
659
660 if (error == -EBADR && !create)
661 goto out_unlock;
662
663 error = get_rsb_struct(ls, name, len, &r);
664 if (error == -EAGAIN) {
665 spin_unlock(&ls->ls_rsbtbl[b].lock);
666 goto retry;
667 }
668 if (error)
669 goto out_unlock;
670
671 r->res_hash = hash;
672 r->res_bucket = b;
673 r->res_dir_nodeid = dir_nodeid;
674 kref_init(&r->res_ref);
675
676 if (from_dir) {
677 /* want to see how often this happens */
678 log_debug(ls, "find_rsb new from_dir %d recreate %s",
679 from_nodeid, r->res_name);
680 r->res_master_nodeid = our_nodeid;
681 r->res_nodeid = 0;
682 goto out_add;
683 }
684
685 if (from_other && (dir_nodeid != our_nodeid)) {
686 /* should never happen */
687 log_error(ls, "find_rsb new from_other %d dir %d our %d %s",
688 from_nodeid, dir_nodeid, our_nodeid, r->res_name);
689 dlm_free_rsb(r);
e8243f32 690 r = NULL;
c04fecb4
DT		 691 error = -ENOTBLK;
692 goto out_unlock;
693 }
694
695 if (from_other) {
696 log_debug(ls, "find_rsb new from_other %d dir %d %s",
697 from_nodeid, dir_nodeid, r->res_name);
698 }
699
700 if (dir_nodeid == our_nodeid) {
701 /* When we are the dir nodeid, we can set the master
702 node immediately */
703 r->res_master_nodeid = our_nodeid;
704 r->res_nodeid = 0;
e7fd4179 705 } else {
c04fecb4
DT		 706 /* set_master will send_lookup to dir_nodeid */
707 r->res_master_nodeid = 0;
708 r->res_nodeid = -1;
709 }
710
711 out_add:
712 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
713 out_unlock:
714 spin_unlock(&ls->ls_rsbtbl[b].lock);
715 out:
716 *r_ret = r;
717 return error;
718}
719
720/* During recovery, other nodes can send us new MSTCPY locks (from
721 dlm_recover_locks) before we've made ourself master (in
722 dlm_recover_masters). */
723
724static int find_rsb_nodir(struct dlm_ls *ls, char *name, int len,
725 uint32_t hash, uint32_t b,
726 int dir_nodeid, int from_nodeid,
727 unsigned int flags, struct dlm_rsb **r_ret)
728{
729 struct dlm_rsb *r = NULL;
730 int our_nodeid = dlm_our_nodeid();
731 int recover = (flags & R_RECEIVE_RECOVER);
732 int error;
733
734 retry:
735 error = pre_rsb_struct(ls);
736 if (error < 0)
737 goto out;
738
739 spin_lock(&ls->ls_rsbtbl[b].lock);
740
741 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
742 if (error)
743 goto do_toss;
744
745 /*
746 * rsb is active, so we can't check master_nodeid without lock_rsb.
747 */
748
749 kref_get(&r->res_ref);
750 goto out_unlock;
751
752
753 do_toss:
754 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
755 if (error)
756 goto do_new;
757
758 /*
759 * rsb found inactive. No other thread is using this rsb because
760 * it's on the toss list, so we can look at or update
761 * res_master_nodeid without lock_rsb.
762 */
763
764 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
765 /* our rsb is not master, and another node has sent us a
766 request; this should never happen */
767 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
768 from_nodeid, r->res_master_nodeid, dir_nodeid);
769 dlm_print_rsb(r);
770 error = -ENOTBLK;
771 goto out_unlock;
e7fd4179 772 }
c04fecb4
DT		 773
774 if (!recover && (r->res_master_nodeid != our_nodeid) &&
775 (dir_nodeid == our_nodeid)) {
776 /* our rsb is not master, and we are dir; may as well fix it;
777 this should never happen */
778 log_error(ls, "find_rsb toss our %d master %d dir %d",
779 our_nodeid, r->res_master_nodeid, dir_nodeid);
780 dlm_print_rsb(r);
781 r->res_master_nodeid = our_nodeid;
782 r->res_nodeid = 0;
783 }
784
785 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
786 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
787 goto out_unlock;
788
789
790 do_new:
791 /*
792 * rsb not found
793 */
794
795 error = get_rsb_struct(ls, name, len, &r);
796 if (error == -EAGAIN) {
797 spin_unlock(&ls->ls_rsbtbl[b].lock);
798 goto retry;
799 }
800 if (error)
801 goto out_unlock;
802
803 r->res_hash = hash;
804 r->res_bucket = b;
805 r->res_dir_nodeid = dir_nodeid;
806 r->res_master_nodeid = dir_nodeid;
807 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
808 kref_init(&r->res_ref);
809
810 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
811 out_unlock:
812 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 813 out:
814 *r_ret = r;
815 return error;
816}
817
c04fecb4
DT		 818static int find_rsb(struct dlm_ls *ls, char *name, int len, int from_nodeid,
819 unsigned int flags, struct dlm_rsb **r_ret)
820{
821 uint32_t hash, b;
822 int dir_nodeid;
823
824 if (len > DLM_RESNAME_MAXLEN)
825 return -EINVAL;
826
827 hash = jhash(name, len, 0);
828 b = hash & (ls->ls_rsbtbl_size - 1);
829
830 dir_nodeid = dlm_hash2nodeid(ls, hash);
831
832 if (dlm_no_directory(ls))
833 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
834 from_nodeid, flags, r_ret);
835 else
836 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
837 from_nodeid, flags, r_ret);
838}
839
840/* we have received a request and found that res_master_nodeid != our_nodeid,
841 so we need to return an error or make ourself the master */
842
843static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
844 int from_nodeid)
845{
846 if (dlm_no_directory(ls)) {
847 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
848 from_nodeid, r->res_master_nodeid,
849 r->res_dir_nodeid);
850 dlm_print_rsb(r);
851 return -ENOTBLK;
852 }
853
854 if (from_nodeid != r->res_dir_nodeid) {
855 /* our rsb is not master, and another node (not the dir node)
856 has sent us a request. this is much more common when our
857 master_nodeid is zero, so limit debug to non-zero. */
858
859 if (r->res_master_nodeid) {
860 log_debug(ls, "validate master from_other %d master %d "
861 "dir %d first %x %s", from_nodeid,
862 r->res_master_nodeid, r->res_dir_nodeid,
863 r->res_first_lkid, r->res_name);
864 }
865 return -ENOTBLK;
866 } else {
867 /* our rsb is not master, but the dir nodeid has sent us a
868 request; this could happen with master 0 / res_nodeid -1 */
869
870 if (r->res_master_nodeid) {
871 log_error(ls, "validate master from_dir %d master %d "
872 "first %x %s",
873 from_nodeid, r->res_master_nodeid,
874 r->res_first_lkid, r->res_name);
875 }
876
877 r->res_master_nodeid = dlm_our_nodeid();
878 r->res_nodeid = 0;
879 return 0;
880 }
881}
882
e7fd4179 883/*
c04fecb4
DT		 884 * We're the dir node for this res and another node wants to know the
885 * master nodeid. During normal operation (non recovery) this is only
886 * called from receive_lookup(); master lookups when the local node is
887 * the dir node are done by find_rsb().
e7fd4179 888 *
c04fecb4
DT		 889 * normal operation, we are the dir node for a resource
890 * . _request_lock
891 * . set_master
892 * . send_lookup
893 * . receive_lookup
894 * . dlm_master_lookup flags 0
e7fd4179 895 *
c04fecb4
DT		 896 * recover directory, we are rebuilding dir for all resources
897 * . dlm_recover_directory
898 * . dlm_rcom_names
899 * remote node sends back the rsb names it is master of and we are dir of
900 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
901 * we either create new rsb setting remote node as master, or find existing
902 * rsb and set master to be the remote node.
903 *
904 * recover masters, we are finding the new master for resources
905 * . dlm_recover_masters
906 * . recover_master
907 * . dlm_send_rcom_lookup
908 * . receive_rcom_lookup
909 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
e7fd4179
DT		 910 */
911
c04fecb4
DT		 912int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, char *name, int len,
913 unsigned int flags, int *r_nodeid, int *result)
e7fd4179 914{
3881ac04 915 struct dlm_rsb *r = NULL;
c04fecb4
DT		 916 uint32_t hash, b;
917 int from_master = (flags & DLM_LU_RECOVER_DIR);
918 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
919 int our_nodeid = dlm_our_nodeid();
920 int dir_nodeid, error, toss_list = 0;
ef58bcca 921
c04fecb4
DT		 922 if (len > DLM_RESNAME_MAXLEN)
923 return -EINVAL;
924
925 if (from_nodeid == our_nodeid) {
926 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
927 our_nodeid, flags);
928 return -EINVAL;
3881ac04 929 }
e7fd4179 930
c04fecb4
DT		 931 hash = jhash(name, len, 0);
932 b = hash & (ls->ls_rsbtbl_size - 1);
e7fd4179 933
c04fecb4
DT		 934 dir_nodeid = dlm_hash2nodeid(ls, hash);
935 if (dir_nodeid != our_nodeid) {
936 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
937 from_nodeid, dir_nodeid, our_nodeid, hash,
938 ls->ls_num_nodes);
939 *r_nodeid = -1;
940 return -EINVAL;
941 }
e7fd4179 942
3881ac04 943 retry:
c04fecb4
DT		 944 error = pre_rsb_struct(ls);
945 if (error < 0)
946 return error;
947
948 spin_lock(&ls->ls_rsbtbl[b].lock);
949 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
950 if (!error) {
951 /* because the rsb is active, we need to lock_rsb before
952 checking/changing re_master_nodeid */
953
954 hold_rsb(r);
955 spin_unlock(&ls->ls_rsbtbl[b].lock);
956 lock_rsb(r);
957 goto found;
3881ac04
DT		 958 }
959
c04fecb4
DT		 960 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
961 if (error)
962 goto not_found;
3881ac04 963
c04fecb4
DT		 964 /* because the rsb is inactive (on toss list), it's not refcounted
965 and lock_rsb is not used, but is protected by the rsbtbl lock */
e7fd4179 966
c04fecb4
DT		 967 toss_list = 1;
968 found:
969 if (r->res_dir_nodeid != our_nodeid) {
970 /* should not happen, but may as well fix it and carry on */
971 log_error(ls, "dlm_master_lookup res_dir %d our %d %s",
972 r->res_dir_nodeid, our_nodeid, r->res_name);
973 r->res_dir_nodeid = our_nodeid;
974 }
975
976 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
977 /* Recovery uses this function to set a new master when
978 the previous master failed. Setting NEW_MASTER will
979 force dlm_recover_masters to call recover_master on this
980 rsb even though the res_nodeid is no longer removed. */
981
982 r->res_master_nodeid = from_nodeid;
983 r->res_nodeid = from_nodeid;
984 rsb_set_flag(r, RSB_NEW_MASTER);
985
986 if (toss_list) {
987 /* I don't think we should ever find it on toss list. */
988 log_error(ls, "dlm_master_lookup fix_master on toss");
989 dlm_dump_rsb(r);
990 }
991 }
e7fd4179 992
c04fecb4
DT		 993 if (from_master && (r->res_master_nodeid != from_nodeid)) {
994 /* this will happen if from_nodeid became master during
995 a previous recovery cycle, and we aborted the previous
996 cycle before recovering this master value */
997
998 log_limit(ls, "dlm_master_lookup from_master %d "
999 "master_nodeid %d res_nodeid %d first %x %s",
1000 from_nodeid, r->res_master_nodeid, r->res_nodeid,
1001 r->res_first_lkid, r->res_name);
1002
1003 if (r->res_master_nodeid == our_nodeid) {
1004 log_error(ls, "from_master %d our_master", from_nodeid);
1005 dlm_dump_rsb(r);
c04fecb4
DT		 1006 goto out_found;
1007 }
1008
1009 r->res_master_nodeid = from_nodeid;
1010 r->res_nodeid = from_nodeid;
1011 rsb_set_flag(r, RSB_NEW_MASTER);
1012 }
1013
1014 if (!r->res_master_nodeid) {
1015 /* this will happen if recovery happens while we're looking
1016 up the master for this rsb */
1017
1018 log_debug(ls, "dlm_master_lookup master 0 to %d first %x %s",
1019 from_nodeid, r->res_first_lkid, r->res_name);
1020 r->res_master_nodeid = from_nodeid;
1021 r->res_nodeid = from_nodeid;
1022 }
1023
1024 if (!from_master && !fix_master &&
1025 (r->res_master_nodeid == from_nodeid)) {
1026 /* this can happen when the master sends remove, the dir node
1027 finds the rsb on the keep list and ignores the remove,
1028 and the former master sends a lookup */
1029
1030 log_limit(ls, "dlm_master_lookup from master %d flags %x "
1031 "first %x %s", from_nodeid, flags,
1032 r->res_first_lkid, r->res_name);
1033 }
1034
1035 out_found:
1036 *r_nodeid = r->res_master_nodeid;
1037 if (result)
1038 *result = DLM_LU_MATCH;
1039
1040 if (toss_list) {
1041 r->res_toss_time = jiffies;
1042 /* the rsb was inactive (on toss list) */
1043 spin_unlock(&ls->ls_rsbtbl[b].lock);
1044 } else {
1045 /* the rsb was active */
1046 unlock_rsb(r);
1047 put_rsb(r);
1048 }
1049 return 0;
e7fd4179 1050
c04fecb4
DT		 1051 not_found:
1052 error = get_rsb_struct(ls, name, len, &r);
3881ac04 1053 if (error == -EAGAIN) {
c04fecb4 1054 spin_unlock(&ls->ls_rsbtbl[b].lock);
3881ac04
DT		 1055 goto retry;
1056 }
1057 if (error)
1058 goto out_unlock;
e7fd4179
DT		 1059
1060 r->res_hash = hash;
c04fecb4
DT		 1061 r->res_bucket = b;
1062 r->res_dir_nodeid = our_nodeid;
1063 r->res_master_nodeid = from_nodeid;
1064 r->res_nodeid = from_nodeid;
e7fd4179 1065 kref_init(&r->res_ref);
c04fecb4 1066 r->res_toss_time = jiffies;
e7fd4179 1067
c04fecb4
DT		 1068 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1069 if (error) {
1070 /* should never happen */
1071 dlm_free_rsb(r);
1072 spin_unlock(&ls->ls_rsbtbl[b].lock);
1073 goto retry;
e7fd4179 1074 }
c04fecb4
DT		 1075
1076 if (result)
1077 *result = DLM_LU_ADD;
1078 *r_nodeid = from_nodeid;
1079 error = 0;
3881ac04 1080 out_unlock:
c04fecb4 1081 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1082 return error;
1083}
1084
6d40c4a7
DT		 1085static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1086{
1087 struct rb_node *n;
1088 struct dlm_rsb *r;
1089 int i;
1090
1091 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1092 spin_lock(&ls->ls_rsbtbl[i].lock);
1093 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1094 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1095 if (r->res_hash == hash)
1096 dlm_dump_rsb(r);
1097 }
1098 spin_unlock(&ls->ls_rsbtbl[i].lock);
1099 }
1100}
1101
c04fecb4 1102void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len)
e7fd4179 1103{
c04fecb4
DT		 1104 struct dlm_rsb *r = NULL;
1105 uint32_t hash, b;
1106 int error;
e7fd4179 1107
c04fecb4
DT		 1108 hash = jhash(name, len, 0);
1109 b = hash & (ls->ls_rsbtbl_size - 1);
1110
1111 spin_lock(&ls->ls_rsbtbl[b].lock);
1112 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1113 if (!error)
1114 goto out_dump;
1115
1116 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1117 if (error)
1118 goto out;
1119 out_dump:
1120 dlm_dump_rsb(r);
1121 out:
1122 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1123}
1124
1125static void toss_rsb(struct kref *kref)
1126{
1127 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1128 struct dlm_ls *ls = r->res_ls;
1129
1130 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1131 kref_init(&r->res_ref);
9beb3bf5
BP		 1132 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1133 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
e7fd4179 1134 r->res_toss_time = jiffies;
f1172283 1135 ls->ls_rsbtbl[r->res_bucket].flags |= DLM_RTF_SHRINK;
e7fd4179 1136 if (r->res_lvbptr) {
52bda2b5 1137 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 1138 r->res_lvbptr = NULL;
1139 }
1140}
1141
e7fd4179
DT		 1142/* See comment for unhold_lkb */
1143
1144static void unhold_rsb(struct dlm_rsb *r)
1145{
1146 int rv;
1147 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 1148 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 1149}
1150
1151static void kill_rsb(struct kref *kref)
1152{
1153 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1154
1155 /* All work is done after the return from kref_put() so we
1156 can release the write_lock before the remove and free. */
1157
a345da3e
DT		 1158 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1159 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1160 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1161 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1162 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1163 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 1164}
1165
1166/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1167 The rsb must exist as long as any lkb's for it do. */
1168
1169static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1170{
1171 hold_rsb(r);
1172 lkb->lkb_resource = r;
1173}
1174
1175static void detach_lkb(struct dlm_lkb *lkb)
1176{
1177 if (lkb->lkb_resource) {
1178 put_rsb(lkb->lkb_resource);
1179 lkb->lkb_resource = NULL;
1180 }
1181}
1182
1183static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1184{
3d6aa675 1185 struct dlm_lkb *lkb;
2a86b3e7 1186 int rv;
e7fd4179 1187
52bda2b5 1188 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 1189 if (!lkb)
1190 return -ENOMEM;
1191
1192 lkb->lkb_nodeid = -1;
1193 lkb->lkb_grmode = DLM_LOCK_IV;
1194 kref_init(&lkb->lkb_ref);
34e22bed 1195 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 1196 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 1197 INIT_LIST_HEAD(&lkb->lkb_time_list);
23e8e1aa
DT		 1198 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1199 mutex_init(&lkb->lkb_cb_mutex);
1200 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
e7fd4179 1201
2a86b3e7 1202 idr_preload(GFP_NOFS);
3d6aa675 1203 spin_lock(&ls->ls_lkbidr_spin);
2a86b3e7
TH		 1204 rv = idr_alloc(&ls->ls_lkbidr, lkb, 1, 0, GFP_NOWAIT);
1205 if (rv >= 0)
1206 lkb->lkb_id = rv;
3d6aa675 1207 spin_unlock(&ls->ls_lkbidr_spin);
2a86b3e7 1208 idr_preload_end();
e7fd4179 1209
3d6aa675
DT		 1210 if (rv < 0) {
1211 log_error(ls, "create_lkb idr error %d", rv);
1212 return rv;
e7fd4179
DT		 1213 }
1214
e7fd4179
DT		 1215 *lkb_ret = lkb;
1216 return 0;
1217}
1218
e7fd4179
DT		 1219static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1220{
1221 struct dlm_lkb *lkb;
e7fd4179 1222
3d6aa675
DT		 1223 spin_lock(&ls->ls_lkbidr_spin);
1224 lkb = idr_find(&ls->ls_lkbidr, lkid);
e7fd4179
DT		 1225 if (lkb)
1226 kref_get(&lkb->lkb_ref);
3d6aa675 1227 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1228
1229 *lkb_ret = lkb;
1230 return lkb ? 0 : -ENOENT;
1231}
1232
1233static void kill_lkb(struct kref *kref)
1234{
1235 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1236
1237 /* All work is done after the return from kref_put() so we
1238 can release the write_lock before the detach_lkb */
1239
1240 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1241}
1242
b3f58d8f
DT		 1243/* __put_lkb() is used when an lkb may not have an rsb attached to
1244 it so we need to provide the lockspace explicitly */
1245
1246static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 1247{
3d6aa675 1248 uint32_t lkid = lkb->lkb_id;
e7fd4179 1249
3d6aa675 1250 spin_lock(&ls->ls_lkbidr_spin);
e7fd4179 1251 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
3d6aa675
DT		 1252 idr_remove(&ls->ls_lkbidr, lkid);
1253 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1254
1255 detach_lkb(lkb);
1256
1257 /* for local/process lkbs, lvbptr points to caller's lksb */
1258 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 1259 dlm_free_lvb(lkb->lkb_lvbptr);
1260 dlm_free_lkb(lkb);
e7fd4179
DT		 1261 return 1;
1262 } else {
3d6aa675 1263 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1264 return 0;
1265 }
1266}
1267
1268int dlm_put_lkb(struct dlm_lkb *lkb)
1269{
b3f58d8f
DT		 1270 struct dlm_ls *ls;
1271
1272 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1273 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1274
1275 ls = lkb->lkb_resource->res_ls;
1276 return __put_lkb(ls, lkb);
e7fd4179
DT		 1277}
1278
1279/* This is only called to add a reference when the code already holds
1280 a valid reference to the lkb, so there's no need for locking. */
1281
1282static inline void hold_lkb(struct dlm_lkb *lkb)
1283{
1284 kref_get(&lkb->lkb_ref);
1285}
1286
1287/* This is called when we need to remove a reference and are certain
1288 it's not the last ref. e.g. del_lkb is always called between a
1289 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1290 put_lkb would work fine, but would involve unnecessary locking */
1291
1292static inline void unhold_lkb(struct dlm_lkb *lkb)
1293{
1294 int rv;
1295 rv = kref_put(&lkb->lkb_ref, kill_lkb);
1296 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
1297}
1298
1299static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1300 int mode)
1301{
1302 struct dlm_lkb *lkb = NULL;
1303
1304 list_for_each_entry(lkb, head, lkb_statequeue)
1305 if (lkb->lkb_rqmode < mode)
1306 break;
1307
99fb19d4 1308 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
e7fd4179
DT		 1309}
1310
1311/* add/remove lkb to rsb's grant/convert/wait queue */
1312
1313static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1314{
1315 kref_get(&lkb->lkb_ref);
1316
1317 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1318
eeda418d
DT		 1319 lkb->lkb_timestamp = ktime_get();
1320
e7fd4179
DT		 1321 lkb->lkb_status = status;
1322
1323 switch (status) {
1324 case DLM_LKSTS_WAITING:
1325 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1326 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1327 else
1328 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1329 break;
1330 case DLM_LKSTS_GRANTED:
1331 /* convention says granted locks kept in order of grmode */
1332 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1333 lkb->lkb_grmode);
1334 break;
1335 case DLM_LKSTS_CONVERT:
1336 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1337 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1338 else
1339 list_add_tail(&lkb->lkb_statequeue,
1340 &r->res_convertqueue);
1341 break;
1342 default:
1343 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1344 }
1345}
1346
1347static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1348{
1349 lkb->lkb_status = 0;
1350 list_del(&lkb->lkb_statequeue);
1351 unhold_lkb(lkb);
1352}
1353
1354static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1355{
1356 hold_lkb(lkb);
1357 del_lkb(r, lkb);
1358 add_lkb(r, lkb, sts);
1359 unhold_lkb(lkb);
1360}
1361
ef0c2bb0
DT		 1362static int msg_reply_type(int mstype)
1363{
1364 switch (mstype) {
1365 case DLM_MSG_REQUEST:
1366 return DLM_MSG_REQUEST_REPLY;
1367 case DLM_MSG_CONVERT:
1368 return DLM_MSG_CONVERT_REPLY;
1369 case DLM_MSG_UNLOCK:
1370 return DLM_MSG_UNLOCK_REPLY;
1371 case DLM_MSG_CANCEL:
1372 return DLM_MSG_CANCEL_REPLY;
1373 case DLM_MSG_LOOKUP:
1374 return DLM_MSG_LOOKUP_REPLY;
1375 }
1376 return -1;
1377}
1378
c6ff669b
DT		 1379static int nodeid_warned(int nodeid, int num_nodes, int *warned)
1380{
1381 int i;
1382
1383 for (i = 0; i < num_nodes; i++) {
1384 if (!warned[i]) {
1385 warned[i] = nodeid;
1386 return 0;
1387 }
1388 if (warned[i] == nodeid)
1389 return 1;
1390 }
1391 return 0;
1392}
1393
1394void dlm_scan_waiters(struct dlm_ls *ls)
1395{
1396 struct dlm_lkb *lkb;
c6ff669b
DT		 1397 s64 us;
1398 s64 debug_maxus = 0;
1399 u32 debug_scanned = 0;
1400 u32 debug_expired = 0;
1401 int num_nodes = 0;
1402 int *warned = NULL;
1403
1404 if (!dlm_config.ci_waitwarn_us)
1405 return;
1406
1407 mutex_lock(&ls->ls_waiters_mutex);
1408
1409 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1f3a8e49 1410 if (!lkb->lkb_wait_time)
c6ff669b
DT		 1411 continue;
1412
1413 debug_scanned++;
1414
1415 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
1416
1417 if (us < dlm_config.ci_waitwarn_us)
1418 continue;
1419
1f3a8e49 1420 lkb->lkb_wait_time = 0;
c6ff669b
DT		 1421
1422 debug_expired++;
1423 if (us > debug_maxus)
1424 debug_maxus = us;
1425
1426 if (!num_nodes) {
1427 num_nodes = ls->ls_num_nodes;
fbb10081 1428 warned = kcalloc(num_nodes, sizeof(int), GFP_KERNEL);
c6ff669b
DT		 1429 }
1430 if (!warned)
1431 continue;
1432 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
1433 continue;
1434
1435 log_error(ls, "waitwarn %x %lld %d us check connection to "
1436 "node %d", lkb->lkb_id, (long long)us,
1437 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
1438 }
1439 mutex_unlock(&ls->ls_waiters_mutex);
5d70828a 1440 kfree(warned);
c6ff669b
DT		 1441
1442 if (debug_expired)
1443 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
1444 debug_scanned, debug_expired,
1445 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
1446}
1447
e7fd4179
DT		 1448/* add/remove lkb from global waiters list of lkb's waiting for
1449 a reply from a remote node */
1450
c6ff669b 1451static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
e7fd4179
DT		 1452{
1453 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 1454 int error = 0;
e7fd4179 1455
90135925 1456 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 1457
1458 if (is_overlap_unlock(lkb) ||
1459 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1460 error = -EINVAL;
1461 goto out;
1462 }
1463
1464 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1465 switch (mstype) {
1466 case DLM_MSG_UNLOCK:
1467 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
1468 break;
1469 case DLM_MSG_CANCEL:
1470 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
1471 break;
1472 default:
1473 error = -EBUSY;
1474 goto out;
1475 }
1476 lkb->lkb_wait_count++;
1477 hold_lkb(lkb);
1478
43279e53 1479 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
ef0c2bb0
DT		 1480 lkb->lkb_id, lkb->lkb_wait_type, mstype,
1481 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 1482 goto out;
1483 }
ef0c2bb0
DT		 1484
1485 DLM_ASSERT(!lkb->lkb_wait_count,
1486 dlm_print_lkb(lkb);
1487 printk("wait_count %d\n", lkb->lkb_wait_count););
1488
1489 lkb->lkb_wait_count++;
e7fd4179 1490 lkb->lkb_wait_type = mstype;
c6ff669b
DT		 1491 lkb->lkb_wait_time = ktime_get();
1492 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
ef0c2bb0 1493 hold_lkb(lkb);
e7fd4179
DT		 1494 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1495 out:
ef0c2bb0 1496 if (error)
43279e53 1497 log_error(ls, "addwait error %x %d flags %x %d %d %s",
ef0c2bb0
DT		 1498 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1499 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 1500 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 1501 return error;
e7fd4179
DT		 1502}
1503
b790c3b7
DT		 1504/* We clear the RESEND flag because we might be taking an lkb off the waiters
1505 list as part of process_requestqueue (e.g. a lookup that has an optimized
1506 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1507 set RESEND and dlm_recover_waiters_post() */
1508
43279e53
DT		 1509static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1510 struct dlm_message *ms)
e7fd4179 1511{
ef0c2bb0
DT		 1512 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1513 int overlap_done = 0;
e7fd4179 1514
ef0c2bb0 1515 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
43279e53 1516 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1517 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1518 overlap_done = 1;
1519 goto out_del;
e7fd4179 1520 }
ef0c2bb0
DT		 1521
1522 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
43279e53 1523 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1524 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1525 overlap_done = 1;
1526 goto out_del;
1527 }
1528
43279e53
DT		 1529 /* Cancel state was preemptively cleared by a successful convert,
1530 see next comment, nothing to do. */
1531
1532 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1533 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1534 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1535 lkb->lkb_id, lkb->lkb_wait_type);
1536 return -1;
1537 }
1538
1539 /* Remove for the convert reply, and premptively remove for the
1540 cancel reply. A convert has been granted while there's still
1541 an outstanding cancel on it (the cancel is moot and the result
1542 in the cancel reply should be 0). We preempt the cancel reply
1543 because the app gets the convert result and then can follow up
1544 with another op, like convert. This subsequent op would see the
1545 lingering state of the cancel and fail with -EBUSY. */
1546
1547 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1548 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1549 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1550 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1551 lkb->lkb_id);
1552 lkb->lkb_wait_type = 0;
1553 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1554 lkb->lkb_wait_count--;
1555 goto out_del;
1556 }
1557
ef0c2bb0
DT		 1558 /* N.B. type of reply may not always correspond to type of original
1559 msg due to lookup->request optimization, verify others? */
1560
1561 if (lkb->lkb_wait_type) {
1562 lkb->lkb_wait_type = 0;
1563 goto out_del;
1564 }
1565
6d40c4a7
DT		 1566 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1567 lkb->lkb_id, ms ? ms->m_header.h_nodeid : 0, lkb->lkb_remid,
1568 mstype, lkb->lkb_flags);
ef0c2bb0
DT		 1569 return -1;
1570
1571 out_del:
1572 /* the force-unlock/cancel has completed and we haven't recvd a reply
1573 to the op that was in progress prior to the unlock/cancel; we
1574 give up on any reply to the earlier op. FIXME: not sure when/how
1575 this would happen */
1576
1577 if (overlap_done && lkb->lkb_wait_type) {
43279e53 1578 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
ef0c2bb0
DT		 1579 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1580 lkb->lkb_wait_count--;
1581 lkb->lkb_wait_type = 0;
1582 }
1583
1584 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1585
b790c3b7 1586 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 1587 lkb->lkb_wait_count--;
1588 if (!lkb->lkb_wait_count)
1589 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 1590 unhold_lkb(lkb);
ef0c2bb0 1591 return 0;
e7fd4179
DT		 1592}
1593
ef0c2bb0 1594static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 1595{
1596 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1597 int error;
1598
90135925 1599 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1600 error = _remove_from_waiters(lkb, mstype, NULL);
90135925 1601 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 1602 return error;
1603}
1604
ef0c2bb0
DT		 1605/* Handles situations where we might be processing a "fake" or "stub" reply in
1606 which we can't try to take waiters_mutex again. */
1607
1608static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1609{
1610 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1611 int error;
1612
2a7ce0ed 1613 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0 1614 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1615 error = _remove_from_waiters(lkb, ms->m_type, ms);
2a7ce0ed 1616 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0
DT		 1617 mutex_unlock(&ls->ls_waiters_mutex);
1618 return error;
1619}
1620
05c32f47
DT		 1621/* If there's an rsb for the same resource being removed, ensure
1622 that the remove message is sent before the new lookup message.
1623 It should be rare to need a delay here, but if not, then it may
1624 be worthwhile to add a proper wait mechanism rather than a delay. */
e7fd4179 1625
05c32f47 1626static void wait_pending_remove(struct dlm_rsb *r)
e7fd4179 1627{
05c32f47
DT		 1628 struct dlm_ls *ls = r->res_ls;
1629 restart:
1630 spin_lock(&ls->ls_remove_spin);
1631 if (ls->ls_remove_len &&
1632 !rsb_cmp(r, ls->ls_remove_name, ls->ls_remove_len)) {
1633 log_debug(ls, "delay lookup for remove dir %d %s",
1634 r->res_dir_nodeid, r->res_name);
1635 spin_unlock(&ls->ls_remove_spin);
1636 msleep(1);
1637 goto restart;
1638 }
1639 spin_unlock(&ls->ls_remove_spin);
1640}
e7fd4179 1641
05c32f47
DT		 1642/*
1643 * ls_remove_spin protects ls_remove_name and ls_remove_len which are
1644 * read by other threads in wait_pending_remove. ls_remove_names
1645 * and ls_remove_lens are only used by the scan thread, so they do
1646 * not need protection.
1647 */
c04fecb4 1648
05c32f47
DT		 1649static void shrink_bucket(struct dlm_ls *ls, int b)
1650{
1651 struct rb_node *n, *next;
1652 struct dlm_rsb *r;
1653 char *name;
1654 int our_nodeid = dlm_our_nodeid();
1655 int remote_count = 0;
f1172283 1656 int need_shrink = 0;
05c32f47 1657 int i, len, rv;
c04fecb4 1658
05c32f47 1659 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
c04fecb4 1660
05c32f47 1661 spin_lock(&ls->ls_rsbtbl[b].lock);
f1172283
DT		 1662
1663 if (!(ls->ls_rsbtbl[b].flags & DLM_RTF_SHRINK)) {
1664 spin_unlock(&ls->ls_rsbtbl[b].lock);
1665 return;
1666 }
1667
05c32f47
DT		 1668 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) {
1669 next = rb_next(n);
1670 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1671
1672 /* If we're the directory record for this rsb, and
1673 we're not the master of it, then we need to wait
1674 for the master node to send us a dir remove for
1675 before removing the dir record. */
1676
1677 if (!dlm_no_directory(ls) &&
1678 (r->res_master_nodeid != our_nodeid) &&
1679 (dlm_dir_nodeid(r) == our_nodeid)) {
1680 continue;
e7fd4179
DT		 1681 }
1682
f1172283
DT		 1683 need_shrink = 1;
1684
05c32f47
DT		 1685 if (!time_after_eq(jiffies, r->res_toss_time +
1686 dlm_config.ci_toss_secs * HZ)) {
1687 continue;
e7fd4179
DT		 1688 }
1689
05c32f47
DT		 1690 if (!dlm_no_directory(ls) &&
1691 (r->res_master_nodeid == our_nodeid) &&
1692 (dlm_dir_nodeid(r) != our_nodeid)) {
e7fd4179 1693
c04fecb4
DT		 1694 /* We're the master of this rsb but we're not
1695 the directory record, so we need to tell the
1696 dir node to remove the dir record. */
1697
05c32f47
DT		 1698 ls->ls_remove_lens[remote_count] = r->res_length;
1699 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1700 DLM_RESNAME_MAXLEN);
1701 remote_count++;
c04fecb4 1702
05c32f47
DT		 1703 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1704 break;
1705 continue;
1706 }
1707
1708 if (!kref_put(&r->res_ref, kill_rsb)) {
e7fd4179 1709 log_error(ls, "tossed rsb in use %s", r->res_name);
05c32f47 1710 continue;
e7fd4179 1711 }
05c32f47
DT		 1712
1713 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1714 dlm_free_rsb(r);
e7fd4179 1715 }
f1172283
DT		 1716
1717 if (need_shrink)
1718 ls->ls_rsbtbl[b].flags |= DLM_RTF_SHRINK;
1719 else
1720 ls->ls_rsbtbl[b].flags &= ~DLM_RTF_SHRINK;
05c32f47 1721 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179 1722
05c32f47
DT		 1723 /*
1724 * While searching for rsb's to free, we found some that require
1725 * remote removal. We leave them in place and find them again here
1726 * so there is a very small gap between removing them from the toss
1727 * list and sending the removal. Keeping this gap small is
1728 * important to keep us (the master node) from being out of sync
1729 * with the remote dir node for very long.
1730 *
1731 * From the time the rsb is removed from toss until just after
1732 * send_remove, the rsb name is saved in ls_remove_name. A new
1733 * lookup checks this to ensure that a new lookup message for the
1734 * same resource name is not sent just before the remove message.
1735 */
1736
1737 for (i = 0; i < remote_count; i++) {
1738 name = ls->ls_remove_names[i];
1739 len = ls->ls_remove_lens[i];
1740
1741 spin_lock(&ls->ls_rsbtbl[b].lock);
1742 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1743 if (rv) {
1744 spin_unlock(&ls->ls_rsbtbl[b].lock);
1745 log_debug(ls, "remove_name not toss %s", name);
1746 continue;
1747 }
1748
1749 if (r->res_master_nodeid != our_nodeid) {
1750 spin_unlock(&ls->ls_rsbtbl[b].lock);
1751 log_debug(ls, "remove_name master %d dir %d our %d %s",
1752 r->res_master_nodeid, r->res_dir_nodeid,
1753 our_nodeid, name);
1754 continue;
1755 }
1756
1757 if (r->res_dir_nodeid == our_nodeid) {
1758 /* should never happen */
1759 spin_unlock(&ls->ls_rsbtbl[b].lock);
1760 log_error(ls, "remove_name dir %d master %d our %d %s",
1761 r->res_dir_nodeid, r->res_master_nodeid,
1762 our_nodeid, name);
1763 continue;
1764 }
1765
1766 if (!time_after_eq(jiffies, r->res_toss_time +
1767 dlm_config.ci_toss_secs * HZ)) {
1768 spin_unlock(&ls->ls_rsbtbl[b].lock);
1769 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1770 r->res_toss_time, jiffies, name);
1771 continue;
1772 }
1773
1774 if (!kref_put(&r->res_ref, kill_rsb)) {
1775 spin_unlock(&ls->ls_rsbtbl[b].lock);
1776 log_error(ls, "remove_name in use %s", name);
1777 continue;
1778 }
1779
1780 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1781
1782 /* block lookup of same name until we've sent remove */
1783 spin_lock(&ls->ls_remove_spin);
1784 ls->ls_remove_len = len;
1785 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
1786 spin_unlock(&ls->ls_remove_spin);
1787 spin_unlock(&ls->ls_rsbtbl[b].lock);
1788
1789 send_remove(r);
1790
1791 /* allow lookup of name again */
1792 spin_lock(&ls->ls_remove_spin);
1793 ls->ls_remove_len = 0;
1794 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
1795 spin_unlock(&ls->ls_remove_spin);
1796
1797 dlm_free_rsb(r);
1798 }
e7fd4179
DT		 1799}
1800
1801void dlm_scan_rsbs(struct dlm_ls *ls)
1802{
1803 int i;
1804
e7fd4179
DT		 1805 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1806 shrink_bucket(ls, i);
85e86edf
DT		 1807 if (dlm_locking_stopped(ls))
1808 break;
e7fd4179
DT		 1809 cond_resched();
1810 }
1811}
1812
3ae1acf9
DT		 1813static void add_timeout(struct dlm_lkb *lkb)
1814{
1815 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1816
eeda418d 1817 if (is_master_copy(lkb))
3ae1acf9 1818 return;
3ae1acf9
DT		 1819
1820 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1821 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1822 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1823 goto add_it;
1824 }
84d8cd69
DT		 1825 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1826 goto add_it;
3ae1acf9
DT		 1827 return;
1828
1829 add_it:
1830 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1831 mutex_lock(&ls->ls_timeout_mutex);
1832 hold_lkb(lkb);
3ae1acf9
DT		 1833 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1834 mutex_unlock(&ls->ls_timeout_mutex);
1835}
1836
1837static void del_timeout(struct dlm_lkb *lkb)
1838{
1839 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1840
1841 mutex_lock(&ls->ls_timeout_mutex);
1842 if (!list_empty(&lkb->lkb_time_list)) {
1843 list_del_init(&lkb->lkb_time_list);
1844 unhold_lkb(lkb);
1845 }
1846 mutex_unlock(&ls->ls_timeout_mutex);
1847}
1848
1849/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1850 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1851 and then lock rsb because of lock ordering in add_timeout. We may need
1852 to specify some special timeout-related bits in the lkb that are just to
1853 be accessed under the timeout_mutex. */
1854
1855void dlm_scan_timeout(struct dlm_ls *ls)
1856{
1857 struct dlm_rsb *r;
1858 struct dlm_lkb *lkb;
1859 int do_cancel, do_warn;
eeda418d 1860 s64 wait_us;
3ae1acf9
DT		 1861
1862 for (;;) {
1863 if (dlm_locking_stopped(ls))
1864 break;
1865
1866 do_cancel = 0;
1867 do_warn = 0;
1868 mutex_lock(&ls->ls_timeout_mutex);
1869 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1870
eeda418d
DT		 1871 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1872 lkb->lkb_timestamp));
1873
3ae1acf9 1874 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
eeda418d 1875 wait_us >= (lkb->lkb_timeout_cs * 10000))
3ae1acf9
DT		 1876 do_cancel = 1;
1877
1878 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
eeda418d 1879 wait_us >= dlm_config.ci_timewarn_cs * 10000)
3ae1acf9
DT		 1880 do_warn = 1;
1881
1882 if (!do_cancel && !do_warn)
1883 continue;
1884 hold_lkb(lkb);
1885 break;
1886 }
1887 mutex_unlock(&ls->ls_timeout_mutex);
1888
1889 if (!do_cancel && !do_warn)
1890 break;
1891
1892 r = lkb->lkb_resource;
1893 hold_rsb(r);
1894 lock_rsb(r);
1895
1896 if (do_warn) {
1897 /* clear flag so we only warn once */
1898 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1899 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1900 del_timeout(lkb);
1901 dlm_timeout_warn(lkb);
1902 }
1903
1904 if (do_cancel) {
b3cab7b9 1905 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1906 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1907 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1908 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1909 del_timeout(lkb);
1910 _cancel_lock(r, lkb);
1911 }
1912
1913 unlock_rsb(r);
1914 unhold_rsb(r);
1915 dlm_put_lkb(lkb);
1916 }
1917}
1918
1919/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1920 dlm_recoverd before checking/setting ls_recover_begin. */
1921
1922void dlm_adjust_timeouts(struct dlm_ls *ls)
1923{
1924 struct dlm_lkb *lkb;
eeda418d 1925 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
3ae1acf9
DT		 1926
1927 ls->ls_recover_begin = 0;
1928 mutex_lock(&ls->ls_timeout_mutex);
1929 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
eeda418d 1930 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
3ae1acf9 1931 mutex_unlock(&ls->ls_timeout_mutex);
c6ff669b
DT		 1932
1933 if (!dlm_config.ci_waitwarn_us)
1934 return;
1935
1936 mutex_lock(&ls->ls_waiters_mutex);
1937 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1938 if (ktime_to_us(lkb->lkb_wait_time))
1939 lkb->lkb_wait_time = ktime_get();
1940 }
1941 mutex_unlock(&ls->ls_waiters_mutex);
3ae1acf9
DT		 1942}
1943
e7fd4179
DT		 1944/* lkb is master or local copy */
1945
1946static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1947{
1948 int b, len = r->res_ls->ls_lvblen;
1949
1950 /* b=1 lvb returned to caller
1951 b=0 lvb written to rsb or invalidated
1952 b=-1 do nothing */
1953
1954 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1955
1956 if (b == 1) {
1957 if (!lkb->lkb_lvbptr)
1958 return;
1959
1960 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1961 return;
1962
1963 if (!r->res_lvbptr)
1964 return;
1965
1966 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1967 lkb->lkb_lvbseq = r->res_lvbseq;
1968
1969 } else if (b == 0) {
1970 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1971 rsb_set_flag(r, RSB_VALNOTVALID);
1972 return;
1973 }
1974
1975 if (!lkb->lkb_lvbptr)
1976 return;
1977
1978 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1979 return;
1980
1981 if (!r->res_lvbptr)
52bda2b5 1982 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1983
1984 if (!r->res_lvbptr)
1985 return;
1986
1987 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1988 r->res_lvbseq++;
1989 lkb->lkb_lvbseq = r->res_lvbseq;
1990 rsb_clear_flag(r, RSB_VALNOTVALID);
1991 }
1992
1993 if (rsb_flag(r, RSB_VALNOTVALID))
1994 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1995}
1996
1997static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1998{
1999 if (lkb->lkb_grmode < DLM_LOCK_PW)
2000 return;
2001
2002 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
2003 rsb_set_flag(r, RSB_VALNOTVALID);
2004 return;
2005 }
2006
2007 if (!lkb->lkb_lvbptr)
2008 return;
2009
2010 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2011 return;
2012
2013 if (!r->res_lvbptr)
52bda2b5 2014 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 2015
2016 if (!r->res_lvbptr)
2017 return;
2018
2019 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2020 r->res_lvbseq++;
2021 rsb_clear_flag(r, RSB_VALNOTVALID);
2022}
2023
2024/* lkb is process copy (pc) */
2025
2026static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2027 struct dlm_message *ms)
2028{
2029 int b;
2030
2031 if (!lkb->lkb_lvbptr)
2032 return;
2033
2034 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2035 return;
2036
597d0cae 2037 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 2038 if (b == 1) {
2039 int len = receive_extralen(ms);
cfa805f6
BVA		 2040 if (len > r->res_ls->ls_lvblen)
2041 len = r->res_ls->ls_lvblen;
e7fd4179
DT		 2042 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
2043 lkb->lkb_lvbseq = ms->m_lvbseq;
2044 }
2045}
2046
2047/* Manipulate lkb's on rsb's convert/granted/waiting queues
2048 remove_lock -- used for unlock, removes lkb from granted
2049 revert_lock -- used for cancel, moves lkb from convert to granted
2050 grant_lock -- used for request and convert, adds lkb to granted or
2051 moves lkb from convert or waiting to granted
2052
2053 Each of these is used for master or local copy lkb's. There is
2054 also a _pc() variation used to make the corresponding change on
2055 a process copy (pc) lkb. */
2056
2057static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2058{
2059 del_lkb(r, lkb);
2060 lkb->lkb_grmode = DLM_LOCK_IV;
2061 /* this unhold undoes the original ref from create_lkb()
2062 so this leads to the lkb being freed */
2063 unhold_lkb(lkb);
2064}
2065
2066static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2067{
2068 set_lvb_unlock(r, lkb);
2069 _remove_lock(r, lkb);
2070}
2071
2072static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2073{
2074 _remove_lock(r, lkb);
2075}
2076
ef0c2bb0
DT		 2077/* returns: 0 did nothing
2078 1 moved lock to granted
2079 -1 removed lock */
2080
2081static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2082{
ef0c2bb0
DT		 2083 int rv = 0;
2084
e7fd4179
DT		 2085 lkb->lkb_rqmode = DLM_LOCK_IV;
2086
2087 switch (lkb->lkb_status) {
597d0cae
DT		 2088 case DLM_LKSTS_GRANTED:
2089 break;
e7fd4179
DT		 2090 case DLM_LKSTS_CONVERT:
2091 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 2092 rv = 1;
e7fd4179
DT		 2093 break;
2094 case DLM_LKSTS_WAITING:
2095 del_lkb(r, lkb);
2096 lkb->lkb_grmode = DLM_LOCK_IV;
2097 /* this unhold undoes the original ref from create_lkb()
2098 so this leads to the lkb being freed */
2099 unhold_lkb(lkb);
ef0c2bb0 2100 rv = -1;
e7fd4179
DT		 2101 break;
2102 default:
2103 log_print("invalid status for revert %d", lkb->lkb_status);
2104 }
ef0c2bb0 2105 return rv;
e7fd4179
DT		 2106}
2107
ef0c2bb0 2108static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2109{
ef0c2bb0 2110 return revert_lock(r, lkb);
e7fd4179
DT		 2111}
2112
2113static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2114{
2115 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
2116 lkb->lkb_grmode = lkb->lkb_rqmode;
2117 if (lkb->lkb_status)
2118 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2119 else
2120 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
2121 }
2122
2123 lkb->lkb_rqmode = DLM_LOCK_IV;
4875647a 2124 lkb->lkb_highbast = 0;
e7fd4179
DT		 2125}
2126
2127static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2128{
2129 set_lvb_lock(r, lkb);
2130 _grant_lock(r, lkb);
e7fd4179
DT		 2131}
2132
2133static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2134 struct dlm_message *ms)
2135{
2136 set_lvb_lock_pc(r, lkb, ms);
2137 _grant_lock(r, lkb);
2138}
2139
2140/* called by grant_pending_locks() which means an async grant message must
2141 be sent to the requesting node in addition to granting the lock if the
2142 lkb belongs to a remote node. */
2143
2144static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
2145{
2146 grant_lock(r, lkb);
2147 if (is_master_copy(lkb))
2148 send_grant(r, lkb);
2149 else
2150 queue_cast(r, lkb, 0);
2151}
2152
7d3c1feb
DT		 2153/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
2154 change the granted/requested modes. We're munging things accordingly in
2155 the process copy.
2156 CONVDEADLK: our grmode may have been forced down to NL to resolve a
2157 conversion deadlock
2158 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
2159 compatible with other granted locks */
2160
2a7ce0ed 2161static void munge_demoted(struct dlm_lkb *lkb)
7d3c1feb 2162{
7d3c1feb
DT		 2163 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
2164 log_print("munge_demoted %x invalid modes gr %d rq %d",
2165 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
2166 return;
2167 }
2168
2169 lkb->lkb_grmode = DLM_LOCK_NL;
2170}
2171
2172static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
2173{
2174 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
2175 ms->m_type != DLM_MSG_GRANT) {
2176 log_print("munge_altmode %x invalid reply type %d",
2177 lkb->lkb_id, ms->m_type);
2178 return;
2179 }
2180
2181 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
2182 lkb->lkb_rqmode = DLM_LOCK_PR;
2183 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
2184 lkb->lkb_rqmode = DLM_LOCK_CW;
2185 else {
2186 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
2187 dlm_print_lkb(lkb);
2188 }
2189}
2190
e7fd4179
DT		 2191static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
2192{
2193 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
2194 lkb_statequeue);
2195 if (lkb->lkb_id == first->lkb_id)
90135925 2196 return 1;
e7fd4179 2197
90135925 2198 return 0;
e7fd4179
DT		 2199}
2200
e7fd4179
DT		 2201/* Check if the given lkb conflicts with another lkb on the queue. */
2202
2203static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
2204{
2205 struct dlm_lkb *this;
2206
2207 list_for_each_entry(this, head, lkb_statequeue) {
2208 if (this == lkb)
2209 continue;
3bcd3687 2210 if (!modes_compat(this, lkb))
90135925 2211 return 1;
e7fd4179 2212 }
90135925 2213 return 0;
e7fd4179
DT		 2214}
2215
2216/*
2217 * "A conversion deadlock arises with a pair of lock requests in the converting
2218 * queue for one resource. The granted mode of each lock blocks the requested
2219 * mode of the other lock."
2220 *
c85d65e9
DT		 2221 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
2222 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 2223 *
2224 * Example:
2225 * Granted Queue: empty
2226 * Convert Queue: NL->EX (first lock)
2227 * PR->EX (second lock)
2228 *
2229 * The first lock can't be granted because of the granted mode of the second
2230 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 2231 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2232 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2233 * flag set and return DEMOTED in the lksb flags.
e7fd4179 2234 *
c85d65e9
DT		 2235 * Originally, this function detected conv-deadlk in a more limited scope:
2236 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2237 * - if lkb1 was the first entry in the queue (not just earlier), and was
2238 * blocked by the granted mode of lkb2, and there was nothing on the
2239 * granted queue preventing lkb1 from being granted immediately, i.e.
2240 * lkb2 was the only thing preventing lkb1 from being granted.
2241 *
2242 * That second condition meant we'd only say there was conv-deadlk if
2243 * resolving it (by demotion) would lead to the first lock on the convert
2244 * queue being granted right away. It allowed conversion deadlocks to exist
2245 * between locks on the convert queue while they couldn't be granted anyway.
2246 *
2247 * Now, we detect and take action on conversion deadlocks immediately when
2248 * they're created, even if they may not be immediately consequential. If
2249 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2250 * mode that would prevent lkb1's conversion from being granted, we do a
2251 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2252 * I think this means that the lkb_is_ahead condition below should always
2253 * be zero, i.e. there will never be conv-deadlk between two locks that are
2254 * both already on the convert queue.
e7fd4179
DT		 2255 */
2256
c85d65e9 2257static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 2258{
c85d65e9
DT		 2259 struct dlm_lkb *lkb1;
2260 int lkb_is_ahead = 0;
e7fd4179 2261
c85d65e9
DT		 2262 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2263 if (lkb1 == lkb2) {
2264 lkb_is_ahead = 1;
e7fd4179
DT		 2265 continue;
2266 }
2267
c85d65e9
DT		 2268 if (!lkb_is_ahead) {
2269 if (!modes_compat(lkb2, lkb1))
2270 return 1;
2271 } else {
2272 if (!modes_compat(lkb2, lkb1) &&
2273 !modes_compat(lkb1, lkb2))
2274 return 1;
2275 }
e7fd4179 2276 }
90135925 2277 return 0;
e7fd4179
DT		 2278}
2279
2280/*
2281 * Return 1 if the lock can be granted, 0 otherwise.
2282 * Also detect and resolve conversion deadlocks.
2283 *
2284 * lkb is the lock to be granted
2285 *
2286 * now is 1 if the function is being called in the context of the
2287 * immediate request, it is 0 if called later, after the lock has been
2288 * queued.
2289 *
c503a621
DT		 2290 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2291 * after recovery.
2292 *
e7fd4179
DT		 2293 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2294 */
2295
c503a621
DT		 2296static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2297 int recover)
e7fd4179
DT		 2298{
2299 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2300
2301 /*
2302 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2303 * a new request for a NL mode lock being blocked.
2304 *
2305 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2306 * request, then it would be granted. In essence, the use of this flag
2307 * tells the Lock Manager to expedite theis request by not considering
2308 * what may be in the CONVERTING or WAITING queues... As of this
2309 * writing, the EXPEDITE flag can be used only with new requests for NL
2310 * mode locks. This flag is not valid for conversion requests.
2311 *
2312 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2313 * conversion or used with a non-NL requested mode. We also know an
2314 * EXPEDITE request is always granted immediately, so now must always
2315 * be 1. The full condition to grant an expedite request: (now &&
2316 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2317 * therefore be shortened to just checking the flag.
2318 */
2319
2320 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 2321 return 1;
e7fd4179
DT		 2322
2323 /*
2324 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2325 * added to the remaining conditions.
2326 */
2327
2328 if (queue_conflict(&r->res_grantqueue, lkb))
c503a621 2329 return 0;
e7fd4179
DT		 2330
2331 /*
2332 * 6-3: By default, a conversion request is immediately granted if the
2333 * requested mode is compatible with the modes of all other granted
2334 * locks
2335 */
2336
2337 if (queue_conflict(&r->res_convertqueue, lkb))
c503a621
DT		 2338 return 0;
2339
2340 /*
2341 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2342 * locks for a recovered rsb, on which lkb's have been rebuilt.
2343 * The lkb's may have been rebuilt on the queues in a different
2344 * order than they were in on the previous master. So, granting
2345 * queued conversions in order after recovery doesn't make sense
2346 * since the order hasn't been preserved anyway. The new order
2347 * could also have created a new "in place" conversion deadlock.
2348 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2349 * After recovery, there would be no granted locks, and possibly
2350 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2351 * recovery, grant conversions without considering order.
2352 */
2353
2354 if (conv && recover)
2355 return 1;
e7fd4179
DT		 2356
2357 /*
2358 * 6-5: But the default algorithm for deciding whether to grant or
2359 * queue conversion requests does not by itself guarantee that such
2360 * requests are serviced on a "first come first serve" basis. This, in
2361 * turn, can lead to a phenomenon known as "indefinate postponement".
2362 *
2363 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2364 * the system service employed to request a lock conversion. This flag
2365 * forces certain conversion requests to be queued, even if they are
2366 * compatible with the granted modes of other locks on the same
2367 * resource. Thus, the use of this flag results in conversion requests
2368 * being ordered on a "first come first servce" basis.
2369 *
2370 * DCT: This condition is all about new conversions being able to occur
2371 * "in place" while the lock remains on the granted queue (assuming
2372 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2373 * doesn't _have_ to go onto the convert queue where it's processed in
2374 * order. The "now" variable is necessary to distinguish converts
2375 * being received and processed for the first time now, because once a
2376 * convert is moved to the conversion queue the condition below applies
2377 * requiring fifo granting.
2378 */
2379
2380 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 2381 return 1;
e7fd4179 2382
53ad1c98
DT		 2383 /*
2384 * Even if the convert is compat with all granted locks,
2385 * QUECVT forces it behind other locks on the convert queue.
2386 */
2387
2388 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2389 if (list_empty(&r->res_convertqueue))
2390 return 1;
2391 else
c503a621 2392 return 0;
53ad1c98
DT		 2393 }
2394
e7fd4179 2395 /*
3bcd3687
DT		 2396 * The NOORDER flag is set to avoid the standard vms rules on grant
2397 * order.
e7fd4179
DT		 2398 */
2399
2400 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 2401 return 1;
e7fd4179
DT		 2402
2403 /*
2404 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2405 * granted until all other conversion requests ahead of it are granted
2406 * and/or canceled.
2407 */
2408
2409 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 2410 return 1;
e7fd4179
DT		 2411
2412 /*
2413 * 6-4: By default, a new request is immediately granted only if all
2414 * three of the following conditions are satisfied when the request is
2415 * issued:
2416 * - The queue of ungranted conversion requests for the resource is
2417 * empty.
2418 * - The queue of ungranted new requests for the resource is empty.
2419 * - The mode of the new request is compatible with the most
2420 * restrictive mode of all granted locks on the resource.
2421 */
2422
2423 if (now && !conv && list_empty(&r->res_convertqueue) &&
2424 list_empty(&r->res_waitqueue))
90135925 2425 return 1;
e7fd4179
DT		 2426
2427 /*
2428 * 6-4: Once a lock request is in the queue of ungranted new requests,
2429 * it cannot be granted until the queue of ungranted conversion
2430 * requests is empty, all ungranted new requests ahead of it are
2431 * granted and/or canceled, and it is compatible with the granted mode
2432 * of the most restrictive lock granted on the resource.
2433 */
2434
2435 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2436 first_in_list(lkb, &r->res_waitqueue))
90135925 2437 return 1;
c503a621 2438
90135925 2439 return 0;
e7fd4179
DT		 2440}
2441
c85d65e9 2442static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
c503a621 2443 int recover, int *err)
e7fd4179 2444{
e7fd4179
DT		 2445 int rv;
2446 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 2447 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2448
2449 if (err)
2450 *err = 0;
e7fd4179 2451
c503a621 2452 rv = _can_be_granted(r, lkb, now, recover);
e7fd4179
DT		 2453 if (rv)
2454 goto out;
2455
c85d65e9
DT		 2456 /*
2457 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2458 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2459 * cancels one of the locks.
2460 */
2461
2462 if (is_convert && can_be_queued(lkb) &&
2463 conversion_deadlock_detect(r, lkb)) {
2464 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2465 lkb->lkb_grmode = DLM_LOCK_NL;
2466 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
294e7e45 2467 } else if (err) {
2468 *err = -EDEADLK;
2469 } else {
2470 log_print("can_be_granted deadlock %x now %d",
2471 lkb->lkb_id, now);
2472 dlm_dump_rsb(r);
c85d65e9 2473 }
e7fd4179 2474 goto out;
c85d65e9 2475 }
e7fd4179 2476
c85d65e9
DT		 2477 /*
2478 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2479 * to grant a request in a mode other than the normal rqmode. It's a
2480 * simple way to provide a big optimization to applications that can
2481 * use them.
2482 */
2483
2484 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 2485 alt = DLM_LOCK_PR;
c85d65e9 2486 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 2487 alt = DLM_LOCK_CW;
2488
2489 if (alt) {
2490 lkb->lkb_rqmode = alt;
c503a621 2491 rv = _can_be_granted(r, lkb, now, 0);
e7fd4179
DT		 2492 if (rv)
2493 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
2494 else
2495 lkb->lkb_rqmode = rqmode;
2496 }
2497 out:
2498 return rv;
2499}
2500
36509258
DT		 2501/* Returns the highest requested mode of all blocked conversions; sets
2502 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 2503
4875647a
DT		 2504static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2505 unsigned int *count)
e7fd4179
DT		 2506{
2507 struct dlm_lkb *lkb, *s;
c503a621 2508 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
e7fd4179 2509 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 2510 int deadlk;
e7fd4179
DT		 2511
2512 quit = 0;
2513 restart:
2514 grant_restart = 0;
2515 demote_restart = 0;
2516 hi = DLM_LOCK_IV;
2517
2518 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2519 demoted = is_demoted(lkb);
c85d65e9
DT		 2520 deadlk = 0;
2521
c503a621 2522 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
e7fd4179
DT		 2523 grant_lock_pending(r, lkb);
2524 grant_restart = 1;
4875647a
DT		 2525 if (count)
2526 (*count)++;
c85d65e9 2527 continue;
e7fd4179 2528 }
c85d65e9
DT		 2529
2530 if (!demoted && is_demoted(lkb)) {
2531 log_print("WARN: pending demoted %x node %d %s",
2532 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2533 demote_restart = 1;
2534 continue;
2535 }
2536
2537 if (deadlk) {
294e7e45 2538 /*
2539 * If DLM_LKB_NODLKWT flag is set and conversion
2540 * deadlock is detected, we request blocking AST and
2541 * down (or cancel) conversion.
2542 */
2543 if (lkb->lkb_exflags & DLM_LKF_NODLCKWT) {
2544 if (lkb->lkb_highbast < lkb->lkb_rqmode) {
2545 queue_bast(r, lkb, lkb->lkb_rqmode);
2546 lkb->lkb_highbast = lkb->lkb_rqmode;
2547 }
2548 } else {
2549 log_print("WARN: pending deadlock %x node %d %s",
2550 lkb->lkb_id, lkb->lkb_nodeid,
2551 r->res_name);
2552 dlm_dump_rsb(r);
2553 }
c85d65e9
DT		 2554 continue;
2555 }
2556
2557 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 2558
2559 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2560 *cw = 1;
e7fd4179
DT		 2561 }
2562
2563 if (grant_restart)
2564 goto restart;
2565 if (demote_restart && !quit) {
2566 quit = 1;
2567 goto restart;
2568 }
2569
2570 return max_t(int, high, hi);
2571}
2572
4875647a
DT		 2573static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2574 unsigned int *count)
e7fd4179
DT		 2575{
2576 struct dlm_lkb *lkb, *s;
2577
2578 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c503a621 2579 if (can_be_granted(r, lkb, 0, 0, NULL)) {
e7fd4179 2580 grant_lock_pending(r, lkb);
4875647a
DT		 2581 if (count)
2582 (*count)++;
2583 } else {
e7fd4179 2584 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 2585 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2586 *cw = 1;
2587 }
e7fd4179
DT		 2588 }
2589
2590 return high;
2591}
2592
36509258
DT		 2593/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2594 on either the convert or waiting queue.
2595 high is the largest rqmode of all locks blocked on the convert or
2596 waiting queue. */
2597
2598static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2599{
2600 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2601 if (gr->lkb_highbast < DLM_LOCK_EX)
2602 return 1;
2603 return 0;
2604 }
2605
2606 if (gr->lkb_highbast < high &&
2607 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2608 return 1;
2609 return 0;
2610}
2611
4875647a 2612static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
e7fd4179
DT		 2613{
2614 struct dlm_lkb *lkb, *s;
2615 int high = DLM_LOCK_IV;
36509258 2616 int cw = 0;
e7fd4179 2617
4875647a
DT		 2618 if (!is_master(r)) {
2619 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2620 dlm_dump_rsb(r);
2621 return;
2622 }
e7fd4179 2623
4875647a
DT		 2624 high = grant_pending_convert(r, high, &cw, count);
2625 high = grant_pending_wait(r, high, &cw, count);
e7fd4179
DT		 2626
2627 if (high == DLM_LOCK_IV)
2628 return;
2629
2630 /*
2631 * If there are locks left on the wait/convert queue then send blocking
2632 * ASTs to granted locks based on the largest requested mode (high)
36509258 2633 * found above.
e7fd4179
DT		 2634 */
2635
2636 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 2637 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
329fc4c3
DT		 2638 if (cw && high == DLM_LOCK_PR &&
2639 lkb->lkb_grmode == DLM_LOCK_PR)
36509258
DT		 2640 queue_bast(r, lkb, DLM_LOCK_CW);
2641 else
2642 queue_bast(r, lkb, high);
e7fd4179
DT		 2643 lkb->lkb_highbast = high;
2644 }
2645 }
2646}
2647
36509258
DT		 2648static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2649{
2650 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2651 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2652 if (gr->lkb_highbast < DLM_LOCK_EX)
2653 return 1;
2654 return 0;
2655 }
2656
2657 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2658 return 1;
2659 return 0;
2660}
2661
e7fd4179
DT		 2662static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2663 struct dlm_lkb *lkb)
2664{
2665 struct dlm_lkb *gr;
2666
2667 list_for_each_entry(gr, head, lkb_statequeue) {
314dd2a0
SW		 2668 /* skip self when sending basts to convertqueue */
2669 if (gr == lkb)
2670 continue;
e5dae548 2671 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 2672 queue_bast(r, gr, lkb->lkb_rqmode);
2673 gr->lkb_highbast = lkb->lkb_rqmode;
2674 }
2675 }
2676}
2677
2678static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2679{
2680 send_bast_queue(r, &r->res_grantqueue, lkb);
2681}
2682
2683static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2684{
2685 send_bast_queue(r, &r->res_grantqueue, lkb);
2686 send_bast_queue(r, &r->res_convertqueue, lkb);
2687}
2688
2689/* set_master(r, lkb) -- set the master nodeid of a resource
2690
2691 The purpose of this function is to set the nodeid field in the given
2692 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2693 known, it can just be copied to the lkb and the function will return
2694 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2695 before it can be copied to the lkb.
2696
2697 When the rsb nodeid is being looked up remotely, the initial lkb
2698 causing the lookup is kept on the ls_waiters list waiting for the
2699 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2700 on the rsb's res_lookup list until the master is verified.
2701
2702 Return values:
2703 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2704 1: the rsb master is not available and the lkb has been placed on
2705 a wait queue
2706*/
2707
2708static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2709{
c04fecb4 2710 int our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 2711
2712 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2713 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2714 r->res_first_lkid = lkb->lkb_id;
2715 lkb->lkb_nodeid = r->res_nodeid;
2716 return 0;
2717 }
2718
2719 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2720 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2721 return 1;
2722 }
2723
c04fecb4 2724 if (r->res_master_nodeid == our_nodeid) {
e7fd4179
DT		 2725 lkb->lkb_nodeid = 0;
2726 return 0;
2727 }
2728
c04fecb4
DT		 2729 if (r->res_master_nodeid) {
2730 lkb->lkb_nodeid = r->res_master_nodeid;
e7fd4179
DT		 2731 return 0;
2732 }
2733
c04fecb4
DT		 2734 if (dlm_dir_nodeid(r) == our_nodeid) {
2735 /* This is a somewhat unusual case; find_rsb will usually
2736 have set res_master_nodeid when dir nodeid is local, but
2737 there are cases where we become the dir node after we've
2738 past find_rsb and go through _request_lock again.
2739 confirm_master() or process_lookup_list() needs to be
2740 called after this. */
2741 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2742 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2743 r->res_name);
2744 r->res_master_nodeid = our_nodeid;
e7fd4179
DT		 2745 r->res_nodeid = 0;
2746 lkb->lkb_nodeid = 0;
c04fecb4 2747 return 0;
e7fd4179 2748 }
c04fecb4 2749
05c32f47
DT		 2750 wait_pending_remove(r);
2751
c04fecb4
DT		 2752 r->res_first_lkid = lkb->lkb_id;
2753 send_lookup(r, lkb);
2754 return 1;
e7fd4179
DT		 2755}
2756
2757static void process_lookup_list(struct dlm_rsb *r)
2758{
2759 struct dlm_lkb *lkb, *safe;
2760
2761 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 2762 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2763 _request_lock(r, lkb);
2764 schedule();
2765 }
2766}
2767
2768/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2769
2770static void confirm_master(struct dlm_rsb *r, int error)
2771{
2772 struct dlm_lkb *lkb;
2773
2774 if (!r->res_first_lkid)
2775 return;
2776
2777 switch (error) {
2778 case 0:
2779 case -EINPROGRESS:
2780 r->res_first_lkid = 0;
2781 process_lookup_list(r);
2782 break;
2783
2784 case -EAGAIN:
aec64e1b
DT		 2785 case -EBADR:
2786 case -ENOTBLK:
2787 /* the remote request failed and won't be retried (it was
2788 a NOQUEUE, or has been canceled/unlocked); make a waiting
2789 lkb the first_lkid */
e7fd4179
DT		 2790
2791 r->res_first_lkid = 0;
2792
2793 if (!list_empty(&r->res_lookup)) {
2794 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2795 lkb_rsb_lookup);
ef0c2bb0 2796 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2797 r->res_first_lkid = lkb->lkb_id;
2798 _request_lock(r, lkb);
761b9d3f 2799 }
e7fd4179
DT		 2800 break;
2801
2802 default:
2803 log_error(r->res_ls, "confirm_master unknown error %d", error);
2804 }
2805}
2806
2807static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 2808 int namelen, unsigned long timeout_cs,
2809 void (*ast) (void *astparam),
2810 void *astparam,
2811 void (*bast) (void *astparam, int mode),
2812 struct dlm_args *args)
e7fd4179
DT		 2813{
2814 int rv = -EINVAL;
2815
2816 /* check for invalid arg usage */
2817
2818 if (mode < 0 || mode > DLM_LOCK_EX)
2819 goto out;
2820
2821 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2822 goto out;
2823
2824 if (flags & DLM_LKF_CANCEL)
2825 goto out;
2826
2827 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2828 goto out;
2829
2830 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2831 goto out;
2832
2833 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2834 goto out;
2835
2836 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2837 goto out;
2838
2839 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2840 goto out;
2841
2842 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2843 goto out;
2844
2845 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2846 goto out;
2847
2848 if (!ast || !lksb)
2849 goto out;
2850
2851 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2852 goto out;
2853
e7fd4179
DT		 2854 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2855 goto out;
2856
2857 /* these args will be copied to the lkb in validate_lock_args,
2858 it cannot be done now because when converting locks, fields in
2859 an active lkb cannot be modified before locking the rsb */
2860
2861 args->flags = flags;
e5dae548
DT		 2862 args->astfn = ast;
2863 args->astparam = astparam;
2864 args->bastfn = bast;
d7db923e 2865 args->timeout = timeout_cs;
e7fd4179
DT		 2866 args->mode = mode;
2867 args->lksb = lksb;
e7fd4179
DT		 2868 rv = 0;
2869 out:
2870 return rv;
2871}
2872
2873static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2874{
2875 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2876 DLM_LKF_FORCEUNLOCK))
2877 return -EINVAL;
2878
ef0c2bb0
DT		 2879 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2880 return -EINVAL;
2881
e7fd4179 2882 args->flags = flags;
e5dae548 2883 args->astparam = astarg;
e7fd4179
DT		 2884 return 0;
2885}
2886
2887static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2888 struct dlm_args *args)
2889{
2890 int rv = -EINVAL;
2891
2892 if (args->flags & DLM_LKF_CONVERT) {
2893 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2894 goto out;
2895
2896 if (args->flags & DLM_LKF_QUECVT &&
2897 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2898 goto out;
2899
2900 rv = -EBUSY;
2901 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2902 goto out;
2903
2904 if (lkb->lkb_wait_type)
2905 goto out;
ef0c2bb0
DT		 2906
2907 if (is_overlap(lkb))
2908 goto out;
e7fd4179
DT		 2909 }
2910
2911 lkb->lkb_exflags = args->flags;
2912 lkb->lkb_sbflags = 0;
e5dae548 2913 lkb->lkb_astfn = args->astfn;
e7fd4179 2914 lkb->lkb_astparam = args->astparam;
e5dae548 2915 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2916 lkb->lkb_rqmode = args->mode;
2917 lkb->lkb_lksb = args->lksb;
2918 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2919 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2920 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2921 rv = 0;
2922 out:
43279e53
DT		 2923 if (rv)
2924 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2925 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2926 lkb->lkb_status, lkb->lkb_wait_type,
2927 lkb->lkb_resource->res_name);
e7fd4179
DT		 2928 return rv;
2929}
2930
ef0c2bb0
DT		 2931/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2932 for success */
2933
2934/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2935 because there may be a lookup in progress and it's valid to do
2936 cancel/unlockf on it */
2937
e7fd4179
DT		 2938static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2939{
ef0c2bb0 2940 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2941 int rv = -EINVAL;
2942
ef0c2bb0
DT		 2943 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2944 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2945 dlm_print_lkb(lkb);
e7fd4179 2946 goto out;
ef0c2bb0 2947 }
e7fd4179 2948
ef0c2bb0
DT		 2949 /* an lkb may still exist even though the lock is EOL'ed due to a
2950 cancel, unlock or failed noqueue request; an app can't use these
2951 locks; return same error as if the lkid had not been found at all */
e7fd4179 2952
ef0c2bb0
DT		 2953 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2954 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2955 rv = -ENOENT;
e7fd4179 2956 goto out;
ef0c2bb0 2957 }
e7fd4179 2958
ef0c2bb0
DT		 2959 /* an lkb may be waiting for an rsb lookup to complete where the
2960 lookup was initiated by another lock */
2961
42dc1601
DT		 2962 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2963 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2964 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2965 list_del_init(&lkb->lkb_rsb_lookup);
2966 queue_cast(lkb->lkb_resource, lkb,
2967 args->flags & DLM_LKF_CANCEL ?
2968 -DLM_ECANCEL : -DLM_EUNLOCK);
2969 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2970 }
42dc1601
DT		 2971 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2972 rv = -EBUSY;
2973 goto out;
ef0c2bb0
DT		 2974 }
2975
2976 /* cancel not allowed with another cancel/unlock in progress */
2977
2978 if (args->flags & DLM_LKF_CANCEL) {
2979 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2980 goto out;
2981
2982 if (is_overlap(lkb))
2983 goto out;
2984
3ae1acf9
DT		 2985 /* don't let scand try to do a cancel */
2986 del_timeout(lkb);
2987
ef0c2bb0
DT		 2988 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2989 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2990 rv = -EBUSY;
2991 goto out;
2992 }
2993
a536e381
DT		 2994 /* there's nothing to cancel */
2995 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2996 !lkb->lkb_wait_type) {
2997 rv = -EBUSY;
2998 goto out;
2999 }
3000
ef0c2bb0
DT		 3001 switch (lkb->lkb_wait_type) {
3002 case DLM_MSG_LOOKUP:
3003 case DLM_MSG_REQUEST:
3004 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
3005 rv = -EBUSY;
3006 goto out;
3007 case DLM_MSG_UNLOCK:
3008 case DLM_MSG_CANCEL:
3009 goto out;
3010 }
3011 /* add_to_waiters() will set OVERLAP_CANCEL */
3012 goto out_ok;
3013 }
3014
3015 /* do we need to allow a force-unlock if there's a normal unlock
3016 already in progress? in what conditions could the normal unlock
3017 fail such that we'd want to send a force-unlock to be sure? */
3018
3019 if (args->flags & DLM_LKF_FORCEUNLOCK) {
3020 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
3021 goto out;
3022
3023 if (is_overlap_unlock(lkb))
3024 goto out;
e7fd4179 3025
3ae1acf9
DT		 3026 /* don't let scand try to do a cancel */
3027 del_timeout(lkb);
3028
ef0c2bb0
DT		 3029 if (lkb->lkb_flags & DLM_IFL_RESEND) {
3030 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3031 rv = -EBUSY;
3032 goto out;
3033 }
3034
3035 switch (lkb->lkb_wait_type) {
3036 case DLM_MSG_LOOKUP:
3037 case DLM_MSG_REQUEST:
3038 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3039 rv = -EBUSY;
3040 goto out;
3041 case DLM_MSG_UNLOCK:
3042 goto out;
3043 }
3044 /* add_to_waiters() will set OVERLAP_UNLOCK */
3045 goto out_ok;
3046 }
3047
3048 /* normal unlock not allowed if there's any op in progress */
e7fd4179 3049 rv = -EBUSY;
ef0c2bb0 3050 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 3051 goto out;
3052
3053 out_ok:
ef0c2bb0
DT		 3054 /* an overlapping op shouldn't blow away exflags from other op */
3055 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 3056 lkb->lkb_sbflags = 0;
3057 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 3058 rv = 0;
3059 out:
ef0c2bb0
DT		 3060 if (rv)
3061 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
3062 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
3063 args->flags, lkb->lkb_wait_type,
3064 lkb->lkb_resource->res_name);
e7fd4179
DT		 3065 return rv;
3066}
3067
3068/*
3069 * Four stage 4 varieties:
3070 * do_request(), do_convert(), do_unlock(), do_cancel()
3071 * These are called on the master node for the given lock and
3072 * from the central locking logic.
3073 */
3074
3075static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3076{
3077 int error = 0;
3078
c503a621 3079 if (can_be_granted(r, lkb, 1, 0, NULL)) {
e7fd4179
DT		 3080 grant_lock(r, lkb);
3081 queue_cast(r, lkb, 0);
3082 goto out;
3083 }
3084
3085 if (can_be_queued(lkb)) {
3086 error = -EINPROGRESS;
3087 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9 3088 add_timeout(lkb);
e7fd4179
DT		 3089 goto out;
3090 }
3091
3092 error = -EAGAIN;
e7fd4179 3093 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3094 out:
3095 return error;
3096}
3097
cf6620ac
DT		 3098static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3099 int error)
3100{
3101 switch (error) {
3102 case -EAGAIN:
3103 if (force_blocking_asts(lkb))
3104 send_blocking_asts_all(r, lkb);
3105 break;
3106 case -EINPROGRESS:
3107 send_blocking_asts(r, lkb);
3108 break;
3109 }
3110}
3111
e7fd4179
DT		 3112static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3113{
3114 int error = 0;
c85d65e9 3115 int deadlk = 0;
e7fd4179
DT		 3116
3117 /* changing an existing lock may allow others to be granted */
3118
c503a621 3119 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
e7fd4179
DT		 3120 grant_lock(r, lkb);
3121 queue_cast(r, lkb, 0);
e7fd4179
DT		 3122 goto out;
3123 }
3124
c85d65e9
DT		 3125 /* can_be_granted() detected that this lock would block in a conversion
3126 deadlock, so we leave it on the granted queue and return EDEADLK in
3127 the ast for the convert. */
3128
294e7e45 3129 if (deadlk && !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
c85d65e9 3130 /* it's left on the granted queue */
c85d65e9
DT		 3131 revert_lock(r, lkb);
3132 queue_cast(r, lkb, -EDEADLK);
3133 error = -EDEADLK;
3134 goto out;
3135 }
3136
7d3c1feb
DT		 3137 /* is_demoted() means the can_be_granted() above set the grmode
3138 to NL, and left us on the granted queue. This auto-demotion
3139 (due to CONVDEADLK) might mean other locks, and/or this lock, are
3140 now grantable. We have to try to grant other converting locks
3141 before we try again to grant this one. */
3142
3143 if (is_demoted(lkb)) {
4875647a 3144 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
c503a621 3145 if (_can_be_granted(r, lkb, 1, 0)) {
7d3c1feb
DT		 3146 grant_lock(r, lkb);
3147 queue_cast(r, lkb, 0);
7d3c1feb
DT		 3148 goto out;
3149 }
3150 /* else fall through and move to convert queue */
3151 }
3152
3153 if (can_be_queued(lkb)) {
e7fd4179
DT		 3154 error = -EINPROGRESS;
3155 del_lkb(r, lkb);
3156 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3157 add_timeout(lkb);
e7fd4179
DT		 3158 goto out;
3159 }
3160
3161 error = -EAGAIN;
e7fd4179 3162 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3163 out:
3164 return error;
3165}
3166
cf6620ac
DT		 3167static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3168 int error)
3169{
3170 switch (error) {
3171 case 0:
4875647a 3172 grant_pending_locks(r, NULL);
cf6620ac
DT		 3173 /* grant_pending_locks also sends basts */
3174 break;
3175 case -EAGAIN:
3176 if (force_blocking_asts(lkb))
3177 send_blocking_asts_all(r, lkb);
3178 break;
3179 case -EINPROGRESS:
3180 send_blocking_asts(r, lkb);
3181 break;
3182 }
3183}
3184
e7fd4179
DT		 3185static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3186{
3187 remove_lock(r, lkb);
3188 queue_cast(r, lkb, -DLM_EUNLOCK);
e7fd4179
DT		 3189 return -DLM_EUNLOCK;
3190}
3191
cf6620ac
DT		 3192static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3193 int error)
3194{
4875647a 3195 grant_pending_locks(r, NULL);
cf6620ac
DT		 3196}
3197
ef0c2bb0 3198/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
c04fecb4 3199
e7fd4179
DT		 3200static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3201{
ef0c2bb0
DT		 3202 int error;
3203
3204 error = revert_lock(r, lkb);
3205 if (error) {
3206 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3207 return -DLM_ECANCEL;
3208 }
3209 return 0;
e7fd4179
DT		 3210}
3211
cf6620ac
DT		 3212static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3213 int error)
3214{
3215 if (error)
4875647a 3216 grant_pending_locks(r, NULL);
cf6620ac
DT		 3217}
3218
e7fd4179
DT		 3219/*
3220 * Four stage 3 varieties:
3221 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3222 */
3223
3224/* add a new lkb to a possibly new rsb, called by requesting process */
3225
3226static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3227{
3228 int error;
3229
3230 /* set_master: sets lkb nodeid from r */
3231
3232 error = set_master(r, lkb);
3233 if (error < 0)
3234 goto out;
3235 if (error) {
3236 error = 0;
3237 goto out;
3238 }
3239
cf6620ac 3240 if (is_remote(r)) {
e7fd4179
DT		 3241 /* receive_request() calls do_request() on remote node */
3242 error = send_request(r, lkb);
cf6620ac 3243 } else {
e7fd4179 3244 error = do_request(r, lkb);
cf6620ac
DT		 3245 /* for remote locks the request_reply is sent
3246 between do_request and do_request_effects */
3247 do_request_effects(r, lkb, error);
3248 }
e7fd4179
DT		 3249 out:
3250 return error;
3251}
3252
3bcd3687 3253/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 3254
3255static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3256{
3257 int error;
3258
cf6620ac 3259 if (is_remote(r)) {
e7fd4179
DT		 3260 /* receive_convert() calls do_convert() on remote node */
3261 error = send_convert(r, lkb);
cf6620ac 3262 } else {
e7fd4179 3263 error = do_convert(r, lkb);
cf6620ac
DT		 3264 /* for remote locks the convert_reply is sent
3265 between do_convert and do_convert_effects */
3266 do_convert_effects(r, lkb, error);
3267 }
e7fd4179
DT		 3268
3269 return error;
3270}
3271
3272/* remove an existing lkb from the granted queue */
3273
3274static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3275{
3276 int error;
3277
cf6620ac 3278 if (is_remote(r)) {
e7fd4179
DT		 3279 /* receive_unlock() calls do_unlock() on remote node */
3280 error = send_unlock(r, lkb);
cf6620ac 3281 } else {
e7fd4179 3282 error = do_unlock(r, lkb);
cf6620ac
DT		 3283 /* for remote locks the unlock_reply is sent
3284 between do_unlock and do_unlock_effects */
3285 do_unlock_effects(r, lkb, error);
3286 }
e7fd4179
DT		 3287
3288 return error;
3289}
3290
3291/* remove an existing lkb from the convert or wait queue */
3292
3293static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3294{
3295 int error;
3296
cf6620ac 3297 if (is_remote(r)) {
e7fd4179
DT		 3298 /* receive_cancel() calls do_cancel() on remote node */
3299 error = send_cancel(r, lkb);
cf6620ac 3300 } else {
e7fd4179 3301 error = do_cancel(r, lkb);
cf6620ac
DT		 3302 /* for remote locks the cancel_reply is sent
3303 between do_cancel and do_cancel_effects */
3304 do_cancel_effects(r, lkb, error);
3305 }
e7fd4179
DT		 3306
3307 return error;
3308}
3309
3310/*
3311 * Four stage 2 varieties:
3312 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3313 */
3314
3315static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
3316 int len, struct dlm_args *args)
3317{
3318 struct dlm_rsb *r;
3319 int error;
3320
3321 error = validate_lock_args(ls, lkb, args);
3322 if (error)
c04fecb4 3323 return error;
e7fd4179 3324
c04fecb4 3325 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
e7fd4179 3326 if (error)
c04fecb4 3327 return error;
e7fd4179
DT		 3328
3329 lock_rsb(r);
3330
3331 attach_lkb(r, lkb);
3332 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3333
3334 error = _request_lock(r, lkb);
3335
3336 unlock_rsb(r);
3337 put_rsb(r);
e7fd4179
DT		 3338 return error;
3339}
3340
3341static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3342 struct dlm_args *args)
3343{
3344 struct dlm_rsb *r;
3345 int error;
3346
3347 r = lkb->lkb_resource;
3348
3349 hold_rsb(r);
3350 lock_rsb(r);
3351
3352 error = validate_lock_args(ls, lkb, args);
3353 if (error)
3354 goto out;
3355
3356 error = _convert_lock(r, lkb);
3357 out:
3358 unlock_rsb(r);
3359 put_rsb(r);
3360 return error;
3361}
3362
3363static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3364 struct dlm_args *args)
3365{
3366 struct dlm_rsb *r;
3367 int error;
3368
3369 r = lkb->lkb_resource;
3370
3371 hold_rsb(r);
3372 lock_rsb(r);
3373
3374 error = validate_unlock_args(lkb, args);
3375 if (error)
3376 goto out;
3377
3378 error = _unlock_lock(r, lkb);
3379 out:
3380 unlock_rsb(r);
3381 put_rsb(r);
3382 return error;
3383}
3384
3385static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3386 struct dlm_args *args)
3387{
3388 struct dlm_rsb *r;
3389 int error;
3390
3391 r = lkb->lkb_resource;
3392
3393 hold_rsb(r);
3394 lock_rsb(r);
3395
3396 error = validate_unlock_args(lkb, args);
3397 if (error)
3398 goto out;
3399
3400 error = _cancel_lock(r, lkb);
3401 out:
3402 unlock_rsb(r);
3403 put_rsb(r);
3404 return error;
3405}
3406
3407/*
3408 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3409 */
3410
3411int dlm_lock(dlm_lockspace_t *lockspace,
3412 int mode,
3413 struct dlm_lksb *lksb,
3414 uint32_t flags,
3415 void *name,
3416 unsigned int namelen,
3417 uint32_t parent_lkid,
3418 void (*ast) (void *astarg),
3419 void *astarg,
3bcd3687 3420 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 3421{
3422 struct dlm_ls *ls;
3423 struct dlm_lkb *lkb;
3424 struct dlm_args args;
3425 int error, convert = flags & DLM_LKF_CONVERT;
3426
3427 ls = dlm_find_lockspace_local(lockspace);
3428 if (!ls)
3429 return -EINVAL;
3430
85e86edf 3431 dlm_lock_recovery(ls);
e7fd4179
DT		 3432
3433 if (convert)
3434 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3435 else
3436 error = create_lkb(ls, &lkb);
3437
3438 if (error)
3439 goto out;
3440
d7db923e 3441 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 3442 astarg, bast, &args);
e7fd4179
DT		 3443 if (error)
3444 goto out_put;
3445
3446 if (convert)
3447 error = convert_lock(ls, lkb, &args);
3448 else
3449 error = request_lock(ls, lkb, name, namelen, &args);
3450
3451 if (error == -EINPROGRESS)
3452 error = 0;
3453 out_put:
3454 if (convert || error)
b3f58d8f 3455 __put_lkb(ls, lkb);
c85d65e9 3456 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 3457 error = 0;
3458 out:
85e86edf 3459 dlm_unlock_recovery(ls);
e7fd4179
DT		 3460 dlm_put_lockspace(ls);
3461 return error;
3462}
3463
3464int dlm_unlock(dlm_lockspace_t *lockspace,
3465 uint32_t lkid,
3466 uint32_t flags,
3467 struct dlm_lksb *lksb,
3468 void *astarg)
3469{
3470 struct dlm_ls *ls;
3471 struct dlm_lkb *lkb;
3472 struct dlm_args args;
3473 int error;
3474
3475 ls = dlm_find_lockspace_local(lockspace);
3476 if (!ls)
3477 return -EINVAL;
3478
85e86edf 3479 dlm_lock_recovery(ls);
e7fd4179
DT		 3480
3481 error = find_lkb(ls, lkid, &lkb);
3482 if (error)
3483 goto out;
3484
3485 error = set_unlock_args(flags, astarg, &args);
3486 if (error)
3487 goto out_put;
3488
3489 if (flags & DLM_LKF_CANCEL)
3490 error = cancel_lock(ls, lkb, &args);
3491 else
3492 error = unlock_lock(ls, lkb, &args);
3493
3494 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3495 error = 0;
ef0c2bb0
DT		 3496 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3497 error = 0;
e7fd4179 3498 out_put:
b3f58d8f 3499 dlm_put_lkb(lkb);
e7fd4179 3500 out:
85e86edf 3501 dlm_unlock_recovery(ls);
e7fd4179
DT		 3502 dlm_put_lockspace(ls);
3503 return error;
3504}
3505
3506/*
3507 * send/receive routines for remote operations and replies
3508 *
3509 * send_args
3510 * send_common
3511 * send_request receive_request
3512 * send_convert receive_convert
3513 * send_unlock receive_unlock
3514 * send_cancel receive_cancel
3515 * send_grant receive_grant
3516 * send_bast receive_bast
3517 * send_lookup receive_lookup
3518 * send_remove receive_remove
3519 *
3520 * send_common_reply
3521 * receive_request_reply send_request_reply
3522 * receive_convert_reply send_convert_reply
3523 * receive_unlock_reply send_unlock_reply
3524 * receive_cancel_reply send_cancel_reply
3525 * receive_lookup_reply send_lookup_reply
3526 */
3527
7e4dac33
DT		 3528static int _create_message(struct dlm_ls *ls, int mb_len,
3529 int to_nodeid, int mstype,
3530 struct dlm_message **ms_ret,
3531 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 3532{
3533 struct dlm_message *ms;
3534 struct dlm_mhandle *mh;
3535 char *mb;
e7fd4179
DT		 3536
3537 /* get_buffer gives us a message handle (mh) that we need to
3538 pass into lowcomms_commit and a message buffer (mb) that we
3539 write our data into */
3540
573c24c4 3541 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
e7fd4179
DT		 3542 if (!mh)
3543 return -ENOBUFS;
3544
3545 memset(mb, 0, mb_len);
3546
3547 ms = (struct dlm_message *) mb;
3548
3549 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 3550 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 3551 ms->m_header.h_nodeid = dlm_our_nodeid();
3552 ms->m_header.h_length = mb_len;
3553 ms->m_header.h_cmd = DLM_MSG;
3554
3555 ms->m_type = mstype;
3556
3557 *mh_ret = mh;
3558 *ms_ret = ms;
3559 return 0;
3560}
3561
7e4dac33
DT		 3562static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3563 int to_nodeid, int mstype,
3564 struct dlm_message **ms_ret,
3565 struct dlm_mhandle **mh_ret)
3566{
3567 int mb_len = sizeof(struct dlm_message);
3568
3569 switch (mstype) {
3570 case DLM_MSG_REQUEST:
3571 case DLM_MSG_LOOKUP:
3572 case DLM_MSG_REMOVE:
3573 mb_len += r->res_length;
3574 break;
3575 case DLM_MSG_CONVERT:
3576 case DLM_MSG_UNLOCK:
3577 case DLM_MSG_REQUEST_REPLY:
3578 case DLM_MSG_CONVERT_REPLY:
3579 case DLM_MSG_GRANT:
3580 if (lkb && lkb->lkb_lvbptr)
3581 mb_len += r->res_ls->ls_lvblen;
3582 break;
3583 }
3584
3585 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3586 ms_ret, mh_ret);
3587}
3588
e7fd4179
DT		 3589/* further lowcomms enhancements or alternate implementations may make
3590 the return value from this function useful at some point */
3591
3592static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
3593{
3594 dlm_message_out(ms);
3595 dlm_lowcomms_commit_buffer(mh);
3596 return 0;
3597}
3598
3599static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3600 struct dlm_message *ms)
3601{
3602 ms->m_nodeid = lkb->lkb_nodeid;
3603 ms->m_pid = lkb->lkb_ownpid;
3604 ms->m_lkid = lkb->lkb_id;
3605 ms->m_remid = lkb->lkb_remid;
3606 ms->m_exflags = lkb->lkb_exflags;
3607 ms->m_sbflags = lkb->lkb_sbflags;
3608 ms->m_flags = lkb->lkb_flags;
3609 ms->m_lvbseq = lkb->lkb_lvbseq;
3610 ms->m_status = lkb->lkb_status;
3611 ms->m_grmode = lkb->lkb_grmode;
3612 ms->m_rqmode = lkb->lkb_rqmode;
3613 ms->m_hash = r->res_hash;
3614
3615 /* m_result and m_bastmode are set from function args,
3616 not from lkb fields */
3617
e5dae548 3618 if (lkb->lkb_bastfn)
8304d6f2 3619 ms->m_asts |= DLM_CB_BAST;
e5dae548 3620 if (lkb->lkb_astfn)
8304d6f2 3621 ms->m_asts |= DLM_CB_CAST;
e7fd4179 3622
da49f36f
DT		 3623 /* compare with switch in create_message; send_remove() doesn't
3624 use send_args() */
e7fd4179 3625
da49f36f
DT		 3626 switch (ms->m_type) {
3627 case DLM_MSG_REQUEST:
3628 case DLM_MSG_LOOKUP:
3629 memcpy(ms->m_extra, r->res_name, r->res_length);
3630 break;
3631 case DLM_MSG_CONVERT:
3632 case DLM_MSG_UNLOCK:
3633 case DLM_MSG_REQUEST_REPLY:
3634 case DLM_MSG_CONVERT_REPLY:
3635 case DLM_MSG_GRANT:
3636 if (!lkb->lkb_lvbptr)
3637 break;
e7fd4179 3638 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 3639 break;
3640 }
e7fd4179
DT		 3641}
3642
3643static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3644{
3645 struct dlm_message *ms;
3646 struct dlm_mhandle *mh;
3647 int to_nodeid, error;
3648
c6ff669b
DT		 3649 to_nodeid = r->res_nodeid;
3650
3651 error = add_to_waiters(lkb, mstype, to_nodeid);
ef0c2bb0
DT		 3652 if (error)
3653 return error;
e7fd4179 3654
e7fd4179
DT		 3655 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3656 if (error)
3657 goto fail;
3658
3659 send_args(r, lkb, ms);
3660
3661 error = send_message(mh, ms);
3662 if (error)
3663 goto fail;
3664 return 0;
3665
3666 fail:
ef0c2bb0 3667 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 3668 return error;
3669}
3670
3671static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3672{
3673 return send_common(r, lkb, DLM_MSG_REQUEST);
3674}
3675
3676static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3677{
3678 int error;
3679
3680 error = send_common(r, lkb, DLM_MSG_CONVERT);
3681
3682 /* down conversions go without a reply from the master */
3683 if (!error && down_conversion(lkb)) {
ef0c2bb0 3684 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2a7ce0ed 3685 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
ef0c2bb0 3686 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179
DT		 3687 r->res_ls->ls_stub_ms.m_result = 0;
3688 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3689 }
3690
3691 return error;
3692}
3693
3694/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3695 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3696 that the master is still correct. */
3697
3698static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3699{
3700 return send_common(r, lkb, DLM_MSG_UNLOCK);
3701}
3702
3703static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3704{
3705 return send_common(r, lkb, DLM_MSG_CANCEL);
3706}
3707
3708static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3709{
3710 struct dlm_message *ms;
3711 struct dlm_mhandle *mh;
3712 int to_nodeid, error;
3713
3714 to_nodeid = lkb->lkb_nodeid;
3715
3716 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3717 if (error)
3718 goto out;
3719
3720 send_args(r, lkb, ms);
3721
3722 ms->m_result = 0;
3723
3724 error = send_message(mh, ms);
3725 out:
3726 return error;
3727}
3728
3729static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3730{
3731 struct dlm_message *ms;
3732 struct dlm_mhandle *mh;
3733 int to_nodeid, error;
3734
3735 to_nodeid = lkb->lkb_nodeid;
3736
3737 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3738 if (error)
3739 goto out;
3740
3741 send_args(r, lkb, ms);
3742
3743 ms->m_bastmode = mode;
3744
3745 error = send_message(mh, ms);
3746 out:
3747 return error;
3748}
3749
3750static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3751{
3752 struct dlm_message *ms;
3753 struct dlm_mhandle *mh;
3754 int to_nodeid, error;
3755
c6ff669b
DT		 3756 to_nodeid = dlm_dir_nodeid(r);
3757
3758 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
ef0c2bb0
DT		 3759 if (error)
3760 return error;
e7fd4179 3761
e7fd4179
DT		 3762 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3763 if (error)
3764 goto fail;
3765
3766 send_args(r, lkb, ms);
3767
3768 error = send_message(mh, ms);
3769 if (error)
3770 goto fail;
3771 return 0;
3772
3773 fail:
ef0c2bb0 3774 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 3775 return error;
3776}
3777
3778static int send_remove(struct dlm_rsb *r)
3779{
3780 struct dlm_message *ms;
3781 struct dlm_mhandle *mh;
3782 int to_nodeid, error;
3783
3784 to_nodeid = dlm_dir_nodeid(r);
3785
3786 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3787 if (error)
3788 goto out;
3789
3790 memcpy(ms->m_extra, r->res_name, r->res_length);
3791 ms->m_hash = r->res_hash;
3792
3793 error = send_message(mh, ms);
3794 out:
3795 return error;
3796}
3797
3798static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3799 int mstype, int rv)
3800{
3801 struct dlm_message *ms;
3802 struct dlm_mhandle *mh;
3803 int to_nodeid, error;
3804
3805 to_nodeid = lkb->lkb_nodeid;
3806
3807 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3808 if (error)
3809 goto out;
3810
3811 send_args(r, lkb, ms);
3812
3813 ms->m_result = rv;
3814
3815 error = send_message(mh, ms);
3816 out:
3817 return error;
3818}
3819
3820static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3821{
3822 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3823}
3824
3825static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3826{
3827 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3828}
3829
3830static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3831{
3832 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3833}
3834
3835static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3836{
3837 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3838}
3839
3840static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3841 int ret_nodeid, int rv)
3842{
3843 struct dlm_rsb *r = &ls->ls_stub_rsb;
3844 struct dlm_message *ms;
3845 struct dlm_mhandle *mh;
3846 int error, nodeid = ms_in->m_header.h_nodeid;
3847
3848 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3849 if (error)
3850 goto out;
3851
3852 ms->m_lkid = ms_in->m_lkid;
3853 ms->m_result = rv;
3854 ms->m_nodeid = ret_nodeid;
3855
3856 error = send_message(mh, ms);
3857 out:
3858 return error;
3859}
3860
3861/* which args we save from a received message depends heavily on the type
3862 of message, unlike the send side where we can safely send everything about
3863 the lkb for any type of message */
3864
3865static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3866{
3867 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 3868 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 3869 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3870 (ms->m_flags & 0x0000FFFF);
3871}
3872
3873static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3874{
2a7ce0ed
DT		 3875 if (ms->m_flags == DLM_IFL_STUB_MS)
3876 return;
3877
e7fd4179
DT		 3878 lkb->lkb_sbflags = ms->m_sbflags;
3879 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3880 (ms->m_flags & 0x0000FFFF);
3881}
3882
3883static int receive_extralen(struct dlm_message *ms)
3884{
3885 return (ms->m_header.h_length - sizeof(struct dlm_message));
3886}
3887
e7fd4179
DT		 3888static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3889 struct dlm_message *ms)
3890{
3891 int len;
3892
3893 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3894 if (!lkb->lkb_lvbptr)
52bda2b5 3895 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 3896 if (!lkb->lkb_lvbptr)
3897 return -ENOMEM;
3898 len = receive_extralen(ms);
cfa805f6
BVA		 3899 if (len > ls->ls_lvblen)
3900 len = ls->ls_lvblen;
e7fd4179
DT		 3901 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3902 }
3903 return 0;
3904}
3905
e5dae548
DT		 3906static void fake_bastfn(void *astparam, int mode)
3907{
3908 log_print("fake_bastfn should not be called");
3909}
3910
3911static void fake_astfn(void *astparam)
3912{
3913 log_print("fake_astfn should not be called");
3914}
3915
e7fd4179
DT		 3916static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3917 struct dlm_message *ms)
3918{
3919 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3920 lkb->lkb_ownpid = ms->m_pid;
3921 lkb->lkb_remid = ms->m_lkid;
3922 lkb->lkb_grmode = DLM_LOCK_IV;
3923 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548 3924
8304d6f2
DT		 3925 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3926 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 3927
8d07fd50
DT		 3928 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3929 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3930 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3931 if (!lkb->lkb_lvbptr)
3932 return -ENOMEM;
3933 }
e7fd4179
DT		 3934
3935 return 0;
3936}
3937
3938static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3939 struct dlm_message *ms)
3940{
e7fd4179
DT		 3941 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3942 return -EBUSY;
3943
e7fd4179
DT		 3944 if (receive_lvb(ls, lkb, ms))
3945 return -ENOMEM;
3946
3947 lkb->lkb_rqmode = ms->m_rqmode;
3948 lkb->lkb_lvbseq = ms->m_lvbseq;
3949
3950 return 0;
3951}
3952
3953static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3954 struct dlm_message *ms)
3955{
e7fd4179
DT		 3956 if (receive_lvb(ls, lkb, ms))
3957 return -ENOMEM;
3958 return 0;
3959}
3960
3961/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3962 uses to send a reply and that the remote end uses to process the reply. */
3963
3964static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3965{
3966 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3967 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3968 lkb->lkb_remid = ms->m_lkid;
3969}
3970
c54e04b0
DT		 3971/* This is called after the rsb is locked so that we can safely inspect
3972 fields in the lkb. */
3973
3974static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3975{
3976 int from = ms->m_header.h_nodeid;
3977 int error = 0;
3978
3979 switch (ms->m_type) {
3980 case DLM_MSG_CONVERT:
3981 case DLM_MSG_UNLOCK:
3982 case DLM_MSG_CANCEL:
3983 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3984 error = -EINVAL;
3985 break;
3986
3987 case DLM_MSG_CONVERT_REPLY:
3988 case DLM_MSG_UNLOCK_REPLY:
3989 case DLM_MSG_CANCEL_REPLY:
3990 case DLM_MSG_GRANT:
3991 case DLM_MSG_BAST:
3992 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3993 error = -EINVAL;
3994 break;
3995
3996 case DLM_MSG_REQUEST_REPLY:
3997 if (!is_process_copy(lkb))
3998 error = -EINVAL;
3999 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
4000 error = -EINVAL;
4001 break;
4002
4003 default:
4004 error = -EINVAL;
4005 }
4006
4007 if (error)
4008 log_error(lkb->lkb_resource->res_ls,
4009 "ignore invalid message %d from %d %x %x %x %d",
4010 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
4011 lkb->lkb_flags, lkb->lkb_nodeid);
4012 return error;
4013}
4014
96006ea6
DT		 4015static void send_repeat_remove(struct dlm_ls *ls, char *ms_name, int len)
4016{
4017 char name[DLM_RESNAME_MAXLEN + 1];
4018 struct dlm_message *ms;
4019 struct dlm_mhandle *mh;
4020 struct dlm_rsb *r;
4021 uint32_t hash, b;
4022 int rv, dir_nodeid;
4023
4024 memset(name, 0, sizeof(name));
4025 memcpy(name, ms_name, len);
4026
4027 hash = jhash(name, len, 0);
4028 b = hash & (ls->ls_rsbtbl_size - 1);
4029
4030 dir_nodeid = dlm_hash2nodeid(ls, hash);
4031
4032 log_error(ls, "send_repeat_remove dir %d %s", dir_nodeid, name);
4033
4034 spin_lock(&ls->ls_rsbtbl[b].lock);
4035 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4036 if (!rv) {
4037 spin_unlock(&ls->ls_rsbtbl[b].lock);
4038 log_error(ls, "repeat_remove on keep %s", name);
4039 return;
4040 }
4041
4042 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4043 if (!rv) {
4044 spin_unlock(&ls->ls_rsbtbl[b].lock);
4045 log_error(ls, "repeat_remove on toss %s", name);
4046 return;
4047 }
4048
4049 /* use ls->remove_name2 to avoid conflict with shrink? */
4050
4051 spin_lock(&ls->ls_remove_spin);
4052 ls->ls_remove_len = len;
4053 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
4054 spin_unlock(&ls->ls_remove_spin);
4055 spin_unlock(&ls->ls_rsbtbl[b].lock);
4056
4057 rv = _create_message(ls, sizeof(struct dlm_message) + len,
4058 dir_nodeid, DLM_MSG_REMOVE, &ms, &mh);
4059 if (rv)
4060 return;
4061
4062 memcpy(ms->m_extra, name, len);
4063 ms->m_hash = hash;
4064
4065 send_message(mh, ms);
4066
4067 spin_lock(&ls->ls_remove_spin);
4068 ls->ls_remove_len = 0;
4069 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
4070 spin_unlock(&ls->ls_remove_spin);
4071}
4072
6d40c4a7 4073static int receive_request(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4074{
4075 struct dlm_lkb *lkb;
4076 struct dlm_rsb *r;
c04fecb4 4077 int from_nodeid;
96006ea6 4078 int error, namelen = 0;
e7fd4179 4079
c04fecb4
DT		 4080 from_nodeid = ms->m_header.h_nodeid;
4081
e7fd4179
DT		 4082 error = create_lkb(ls, &lkb);
4083 if (error)
4084 goto fail;
4085
4086 receive_flags(lkb, ms);
4087 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4088 error = receive_request_args(ls, lkb, ms);
4089 if (error) {
b3f58d8f 4090 __put_lkb(ls, lkb);
e7fd4179
DT		 4091 goto fail;
4092 }
4093
c04fecb4
DT		 4094 /* The dir node is the authority on whether we are the master
4095 for this rsb or not, so if the master sends us a request, we should
4096 recreate the rsb if we've destroyed it. This race happens when we
4097 send a remove message to the dir node at the same time that the dir
4098 node sends us a request for the rsb. */
4099
e7fd4179
DT		 4100 namelen = receive_extralen(ms);
4101
c04fecb4
DT		 4102 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
4103 R_RECEIVE_REQUEST, &r);
e7fd4179 4104 if (error) {
b3f58d8f 4105 __put_lkb(ls, lkb);
e7fd4179
DT		 4106 goto fail;
4107 }
4108
4109 lock_rsb(r);
4110
c04fecb4
DT		 4111 if (r->res_master_nodeid != dlm_our_nodeid()) {
4112 error = validate_master_nodeid(ls, r, from_nodeid);
4113 if (error) {
4114 unlock_rsb(r);
4115 put_rsb(r);
4116 __put_lkb(ls, lkb);
4117 goto fail;
4118 }
4119 }
4120
e7fd4179
DT		 4121 attach_lkb(r, lkb);
4122 error = do_request(r, lkb);
4123 send_request_reply(r, lkb, error);
cf6620ac 4124 do_request_effects(r, lkb, error);
e7fd4179
DT		 4125
4126 unlock_rsb(r);
4127 put_rsb(r);
4128
4129 if (error == -EINPROGRESS)
4130 error = 0;
4131 if (error)
b3f58d8f 4132 dlm_put_lkb(lkb);
6d40c4a7 4133 return 0;
e7fd4179
DT		 4134
4135 fail:
c04fecb4
DT		 4136 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
4137 and do this receive_request again from process_lookup_list once
4138 we get the lookup reply. This would avoid a many repeated
4139 ENOTBLK request failures when the lookup reply designating us
4140 as master is delayed. */
4141
4142 /* We could repeatedly return -EBADR here if our send_remove() is
4143 delayed in being sent/arriving/being processed on the dir node.
4144 Another node would repeatedly lookup up the master, and the dir
4145 node would continue returning our nodeid until our send_remove
96006ea6
DT		 4146 took effect.
4147
4148 We send another remove message in case our previous send_remove
4149 was lost/ignored/missed somehow. */
c04fecb4
DT		 4150
4151 if (error != -ENOTBLK) {
4152 log_limit(ls, "receive_request %x from %d %d",
4153 ms->m_lkid, from_nodeid, error);
4154 }
4155
96006ea6
DT		 4156 if (namelen && error == -EBADR) {
4157 send_repeat_remove(ls, ms->m_extra, namelen);
4158 msleep(1000);
4159 }
4160
e7fd4179
DT		 4161 setup_stub_lkb(ls, ms);
4162 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4163 return error;
e7fd4179
DT		 4164}
4165
6d40c4a7 4166static int receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4167{
4168 struct dlm_lkb *lkb;
4169 struct dlm_rsb *r;
90135925 4170 int error, reply = 1;
e7fd4179
DT		 4171
4172 error = find_lkb(ls, ms->m_remid, &lkb);
4173 if (error)
4174 goto fail;
4175
6d40c4a7 4176 if (lkb->lkb_remid != ms->m_lkid) {
4875647a
DT		 4177 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
4178 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
4179 (unsigned long long)lkb->lkb_recover_seq,
6d40c4a7
DT		 4180 ms->m_header.h_nodeid, ms->m_lkid);
4181 error = -ENOENT;
4182 goto fail;
4183 }
4184
e7fd4179
DT		 4185 r = lkb->lkb_resource;
4186
4187 hold_rsb(r);
4188 lock_rsb(r);
4189
c54e04b0
DT		 4190 error = validate_message(lkb, ms);
4191 if (error)
4192 goto out;
4193
e7fd4179 4194 receive_flags(lkb, ms);
cf6620ac 4195
e7fd4179 4196 error = receive_convert_args(ls, lkb, ms);
cf6620ac
DT		 4197 if (error) {
4198 send_convert_reply(r, lkb, error);
4199 goto out;
4200 }
4201
e7fd4179
DT		 4202 reply = !down_conversion(lkb);
4203
4204 error = do_convert(r, lkb);
e7fd4179
DT		 4205 if (reply)
4206 send_convert_reply(r, lkb, error);
cf6620ac 4207 do_convert_effects(r, lkb, error);
c54e04b0 4208 out:
e7fd4179
DT		 4209 unlock_rsb(r);
4210 put_rsb(r);
b3f58d8f 4211 dlm_put_lkb(lkb);
6d40c4a7 4212 return 0;
e7fd4179
DT		 4213
4214 fail:
4215 setup_stub_lkb(ls, ms);
4216 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4217 return error;
e7fd4179
DT		 4218}
4219
6d40c4a7 4220static int receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4221{
4222 struct dlm_lkb *lkb;
4223 struct dlm_rsb *r;
4224 int error;
4225
4226 error = find_lkb(ls, ms->m_remid, &lkb);
4227 if (error)
4228 goto fail;
4229
6d40c4a7
DT		 4230 if (lkb->lkb_remid != ms->m_lkid) {
4231 log_error(ls, "receive_unlock %x remid %x remote %d %x",
4232 lkb->lkb_id, lkb->lkb_remid,
4233 ms->m_header.h_nodeid, ms->m_lkid);
4234 error = -ENOENT;
4235 goto fail;
4236 }
4237
e7fd4179
DT		 4238 r = lkb->lkb_resource;
4239
4240 hold_rsb(r);
4241 lock_rsb(r);
4242
c54e04b0
DT		 4243 error = validate_message(lkb, ms);
4244 if (error)
4245 goto out;
4246
e7fd4179 4247 receive_flags(lkb, ms);
cf6620ac 4248
e7fd4179 4249 error = receive_unlock_args(ls, lkb, ms);
cf6620ac
DT		 4250 if (error) {
4251 send_unlock_reply(r, lkb, error);
4252 goto out;
4253 }
e7fd4179
DT		 4254
4255 error = do_unlock(r, lkb);
e7fd4179 4256 send_unlock_reply(r, lkb, error);
cf6620ac 4257 do_unlock_effects(r, lkb, error);
c54e04b0 4258 out:
e7fd4179
DT		 4259 unlock_rsb(r);
4260 put_rsb(r);
b3f58d8f 4261 dlm_put_lkb(lkb);
6d40c4a7 4262 return 0;
e7fd4179
DT		 4263
4264 fail:
4265 setup_stub_lkb(ls, ms);
4266 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4267 return error;
e7fd4179
DT		 4268}
4269
6d40c4a7 4270static int receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4271{
4272 struct dlm_lkb *lkb;
4273 struct dlm_rsb *r;
4274 int error;
4275
4276 error = find_lkb(ls, ms->m_remid, &lkb);
4277 if (error)
4278 goto fail;
4279
4280 receive_flags(lkb, ms);
4281
4282 r = lkb->lkb_resource;
4283
4284 hold_rsb(r);
4285 lock_rsb(r);
4286
c54e04b0
DT		 4287 error = validate_message(lkb, ms);
4288 if (error)
4289 goto out;
4290
e7fd4179
DT		 4291 error = do_cancel(r, lkb);
4292 send_cancel_reply(r, lkb, error);
cf6620ac 4293 do_cancel_effects(r, lkb, error);
c54e04b0 4294 out:
e7fd4179
DT		 4295 unlock_rsb(r);
4296 put_rsb(r);
b3f58d8f 4297 dlm_put_lkb(lkb);
6d40c4a7 4298 return 0;
e7fd4179
DT		 4299
4300 fail:
4301 setup_stub_lkb(ls, ms);
4302 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4303 return error;
e7fd4179
DT		 4304}
4305
6d40c4a7 4306static int receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4307{
4308 struct dlm_lkb *lkb;
4309 struct dlm_rsb *r;
4310 int error;
4311
4312 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4313 if (error)
4314 return error;
e7fd4179
DT		 4315
4316 r = lkb->lkb_resource;
4317
4318 hold_rsb(r);
4319 lock_rsb(r);
4320
c54e04b0
DT		 4321 error = validate_message(lkb, ms);
4322 if (error)
4323 goto out;
4324
e7fd4179 4325 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 4326 if (is_altmode(lkb))
4327 munge_altmode(lkb, ms);
e7fd4179
DT		 4328 grant_lock_pc(r, lkb, ms);
4329 queue_cast(r, lkb, 0);
c54e04b0 4330 out:
e7fd4179
DT		 4331 unlock_rsb(r);
4332 put_rsb(r);
b3f58d8f 4333 dlm_put_lkb(lkb);
6d40c4a7 4334 return 0;
e7fd4179
DT		 4335}
4336
6d40c4a7 4337static int receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4338{
4339 struct dlm_lkb *lkb;
4340 struct dlm_rsb *r;
4341 int error;
4342
4343 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4344 if (error)
4345 return error;
e7fd4179
DT		 4346
4347 r = lkb->lkb_resource;
4348
4349 hold_rsb(r);
4350 lock_rsb(r);
4351
c54e04b0
DT		 4352 error = validate_message(lkb, ms);
4353 if (error)
4354 goto out;
e7fd4179 4355
c54e04b0 4356 queue_bast(r, lkb, ms->m_bastmode);
4875647a 4357 lkb->lkb_highbast = ms->m_bastmode;
c54e04b0 4358 out:
e7fd4179
DT		 4359 unlock_rsb(r);
4360 put_rsb(r);
b3f58d8f 4361 dlm_put_lkb(lkb);
6d40c4a7 4362 return 0;
e7fd4179
DT		 4363}
4364
4365static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
4366{
c04fecb4 4367 int len, error, ret_nodeid, from_nodeid, our_nodeid;
e7fd4179
DT		 4368
4369 from_nodeid = ms->m_header.h_nodeid;
4370 our_nodeid = dlm_our_nodeid();
4371
4372 len = receive_extralen(ms);
4373
c04fecb4
DT		 4374 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4375 &ret_nodeid, NULL);
e7fd4179
DT		 4376
4377 /* Optimization: we're master so treat lookup as a request */
4378 if (!error && ret_nodeid == our_nodeid) {
4379 receive_request(ls, ms);
4380 return;
4381 }
e7fd4179
DT		 4382 send_lookup_reply(ls, ms, ret_nodeid, error);
4383}
4384
4385static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
4386{
c04fecb4
DT		 4387 char name[DLM_RESNAME_MAXLEN+1];
4388 struct dlm_rsb *r;
4389 uint32_t hash, b;
4390 int rv, len, dir_nodeid, from_nodeid;
e7fd4179
DT		 4391
4392 from_nodeid = ms->m_header.h_nodeid;
4393
4394 len = receive_extralen(ms);
4395
c04fecb4
DT		 4396 if (len > DLM_RESNAME_MAXLEN) {
4397 log_error(ls, "receive_remove from %d bad len %d",
4398 from_nodeid, len);
4399 return;
4400 }
4401
e7fd4179
DT		 4402 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
4403 if (dir_nodeid != dlm_our_nodeid()) {
c04fecb4
DT		 4404 log_error(ls, "receive_remove from %d bad nodeid %d",
4405 from_nodeid, dir_nodeid);
e7fd4179
DT		 4406 return;
4407 }
4408
c04fecb4
DT		 4409 /* Look for name on rsbtbl.toss, if it's there, kill it.
4410 If it's on rsbtbl.keep, it's being used, and we should ignore this
4411 message. This is an expected race between the dir node sending a
4412 request to the master node at the same time as the master node sends
4413 a remove to the dir node. The resolution to that race is for the
4414 dir node to ignore the remove message, and the master node to
4415 recreate the master rsb when it gets a request from the dir node for
4416 an rsb it doesn't have. */
4417
4418 memset(name, 0, sizeof(name));
4419 memcpy(name, ms->m_extra, len);
4420
4421 hash = jhash(name, len, 0);
4422 b = hash & (ls->ls_rsbtbl_size - 1);
4423
4424 spin_lock(&ls->ls_rsbtbl[b].lock);
4425
4426 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4427 if (rv) {
4428 /* verify the rsb is on keep list per comment above */
4429 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4430 if (rv) {
4431 /* should not happen */
4432 log_error(ls, "receive_remove from %d not found %s",
4433 from_nodeid, name);
4434 spin_unlock(&ls->ls_rsbtbl[b].lock);
4435 return;
4436 }
4437 if (r->res_master_nodeid != from_nodeid) {
4438 /* should not happen */
4439 log_error(ls, "receive_remove keep from %d master %d",
4440 from_nodeid, r->res_master_nodeid);
4441 dlm_print_rsb(r);
4442 spin_unlock(&ls->ls_rsbtbl[b].lock);
4443 return;
4444 }
4445
4446 log_debug(ls, "receive_remove from %d master %d first %x %s",
4447 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4448 name);
4449 spin_unlock(&ls->ls_rsbtbl[b].lock);
4450 return;
4451 }
4452
4453 if (r->res_master_nodeid != from_nodeid) {
4454 log_error(ls, "receive_remove toss from %d master %d",
4455 from_nodeid, r->res_master_nodeid);
4456 dlm_print_rsb(r);
4457 spin_unlock(&ls->ls_rsbtbl[b].lock);
4458 return;
4459 }
4460
4461 if (kref_put(&r->res_ref, kill_rsb)) {
4462 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4463 spin_unlock(&ls->ls_rsbtbl[b].lock);
4464 dlm_free_rsb(r);
4465 } else {
4466 log_error(ls, "receive_remove from %d rsb ref error",
4467 from_nodeid);
4468 dlm_print_rsb(r);
4469 spin_unlock(&ls->ls_rsbtbl[b].lock);
4470 }
e7fd4179
DT		 4471}
4472
8499137d
DT		 4473static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
4474{
4475 do_purge(ls, ms->m_nodeid, ms->m_pid);
4476}
4477
6d40c4a7 4478static int receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4479{
4480 struct dlm_lkb *lkb;
4481 struct dlm_rsb *r;
ef0c2bb0 4482 int error, mstype, result;
c04fecb4 4483 int from_nodeid = ms->m_header.h_nodeid;
e7fd4179
DT		 4484
4485 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4486 if (error)
4487 return error;
e7fd4179 4488
e7fd4179
DT		 4489 r = lkb->lkb_resource;
4490 hold_rsb(r);
4491 lock_rsb(r);
4492
c54e04b0
DT		 4493 error = validate_message(lkb, ms);
4494 if (error)
4495 goto out;
4496
ef0c2bb0
DT		 4497 mstype = lkb->lkb_wait_type;
4498 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4875647a
DT		 4499 if (error) {
4500 log_error(ls, "receive_request_reply %x remote %d %x result %d",
c04fecb4 4501 lkb->lkb_id, from_nodeid, ms->m_lkid, ms->m_result);
4875647a 4502 dlm_dump_rsb(r);
ef0c2bb0 4503 goto out;
4875647a 4504 }
ef0c2bb0 4505
e7fd4179
DT		 4506 /* Optimization: the dir node was also the master, so it took our
4507 lookup as a request and sent request reply instead of lookup reply */
4508 if (mstype == DLM_MSG_LOOKUP) {
c04fecb4
DT		 4509 r->res_master_nodeid = from_nodeid;
4510 r->res_nodeid = from_nodeid;
4511 lkb->lkb_nodeid = from_nodeid;
e7fd4179
DT		 4512 }
4513
ef0c2bb0
DT		 4514 /* this is the value returned from do_request() on the master */
4515 result = ms->m_result;
4516
4517 switch (result) {
e7fd4179 4518 case -EAGAIN:
ef0c2bb0 4519 /* request would block (be queued) on remote master */
e7fd4179
DT		 4520 queue_cast(r, lkb, -EAGAIN);
4521 confirm_master(r, -EAGAIN);
ef0c2bb0 4522 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 4523 break;
4524
4525 case -EINPROGRESS:
4526 case 0:
4527 /* request was queued or granted on remote master */
4528 receive_flags_reply(lkb, ms);
4529 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 4530 if (is_altmode(lkb))
4531 munge_altmode(lkb, ms);
3ae1acf9 4532 if (result) {
e7fd4179 4533 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 4534 add_timeout(lkb);
4535 } else {
e7fd4179
DT		 4536 grant_lock_pc(r, lkb, ms);
4537 queue_cast(r, lkb, 0);
4538 }
ef0c2bb0 4539 confirm_master(r, result);
e7fd4179
DT		 4540 break;
4541
597d0cae 4542 case -EBADR:
e7fd4179
DT		 4543 case -ENOTBLK:
4544 /* find_rsb failed to find rsb or rsb wasn't master */
c04fecb4
DT		 4545 log_limit(ls, "receive_request_reply %x from %d %d "
4546 "master %d dir %d first %x %s", lkb->lkb_id,
4547 from_nodeid, result, r->res_master_nodeid,
4548 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4549
4550 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4551 r->res_master_nodeid != dlm_our_nodeid()) {
4552 /* cause _request_lock->set_master->send_lookup */
4553 r->res_master_nodeid = 0;
4554 r->res_nodeid = -1;
4555 lkb->lkb_nodeid = -1;
4556 }
ef0c2bb0
DT		 4557
4558 if (is_overlap(lkb)) {
4559 /* we'll ignore error in cancel/unlock reply */
4560 queue_cast_overlap(r, lkb);
aec64e1b 4561 confirm_master(r, result);
ef0c2bb0 4562 unhold_lkb(lkb); /* undoes create_lkb() */
c04fecb4 4563 } else {
ef0c2bb0 4564 _request_lock(r, lkb);
c04fecb4
DT		 4565
4566 if (r->res_master_nodeid == dlm_our_nodeid())
4567 confirm_master(r, 0);
4568 }
e7fd4179
DT		 4569 break;
4570
4571 default:
ef0c2bb0
DT		 4572 log_error(ls, "receive_request_reply %x error %d",
4573 lkb->lkb_id, result);
e7fd4179
DT		 4574 }
4575
ef0c2bb0
DT		 4576 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
4577 log_debug(ls, "receive_request_reply %x result %d unlock",
4578 lkb->lkb_id, result);
4579 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4580 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4581 send_unlock(r, lkb);
4582 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
4583 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4584 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4585 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4586 send_cancel(r, lkb);
4587 } else {
4588 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4589 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4590 }
4591 out:
e7fd4179
DT		 4592 unlock_rsb(r);
4593 put_rsb(r);
b3f58d8f 4594 dlm_put_lkb(lkb);
6d40c4a7 4595 return 0;
e7fd4179
DT		 4596}
4597
4598static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4599 struct dlm_message *ms)
4600{
e7fd4179 4601 /* this is the value returned from do_convert() on the master */
ef0c2bb0 4602 switch (ms->m_result) {
e7fd4179
DT		 4603 case -EAGAIN:
4604 /* convert would block (be queued) on remote master */
4605 queue_cast(r, lkb, -EAGAIN);
4606 break;
4607
c85d65e9
DT		 4608 case -EDEADLK:
4609 receive_flags_reply(lkb, ms);
4610 revert_lock_pc(r, lkb);
4611 queue_cast(r, lkb, -EDEADLK);
4612 break;
4613
e7fd4179
DT		 4614 case -EINPROGRESS:
4615 /* convert was queued on remote master */
7d3c1feb
DT		 4616 receive_flags_reply(lkb, ms);
4617 if (is_demoted(lkb))
2a7ce0ed 4618 munge_demoted(lkb);
e7fd4179
DT		 4619 del_lkb(r, lkb);
4620 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 4621 add_timeout(lkb);
e7fd4179
DT		 4622 break;
4623
4624 case 0:
4625 /* convert was granted on remote master */
4626 receive_flags_reply(lkb, ms);
7d3c1feb 4627 if (is_demoted(lkb))
2a7ce0ed 4628 munge_demoted(lkb);
e7fd4179
DT		 4629 grant_lock_pc(r, lkb, ms);
4630 queue_cast(r, lkb, 0);
4631 break;
4632
4633 default:
6d40c4a7
DT		 4634 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4635 lkb->lkb_id, ms->m_header.h_nodeid, ms->m_lkid,
4636 ms->m_result);
4637 dlm_print_rsb(r);
4638 dlm_print_lkb(lkb);
e7fd4179
DT		 4639 }
4640}
4641
4642static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4643{
4644 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4645 int error;
e7fd4179
DT		 4646
4647 hold_rsb(r);
4648 lock_rsb(r);
4649
c54e04b0
DT		 4650 error = validate_message(lkb, ms);
4651 if (error)
4652 goto out;
4653
ef0c2bb0
DT		 4654 /* stub reply can happen with waiters_mutex held */
4655 error = remove_from_waiters_ms(lkb, ms);
4656 if (error)
4657 goto out;
e7fd4179 4658
ef0c2bb0
DT		 4659 __receive_convert_reply(r, lkb, ms);
4660 out:
e7fd4179
DT		 4661 unlock_rsb(r);
4662 put_rsb(r);
4663}
4664
6d40c4a7 4665static int receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4666{
4667 struct dlm_lkb *lkb;
4668 int error;
4669
4670 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4671 if (error)
4672 return error;
e7fd4179 4673
e7fd4179 4674 _receive_convert_reply(lkb, ms);
b3f58d8f 4675 dlm_put_lkb(lkb);
6d40c4a7 4676 return 0;
e7fd4179
DT		 4677}
4678
4679static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4680{
4681 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4682 int error;
e7fd4179
DT		 4683
4684 hold_rsb(r);
4685 lock_rsb(r);
4686
c54e04b0
DT		 4687 error = validate_message(lkb, ms);
4688 if (error)
4689 goto out;
4690
ef0c2bb0
DT		 4691 /* stub reply can happen with waiters_mutex held */
4692 error = remove_from_waiters_ms(lkb, ms);
4693 if (error)
4694 goto out;
4695
e7fd4179
DT		 4696 /* this is the value returned from do_unlock() on the master */
4697
ef0c2bb0 4698 switch (ms->m_result) {
e7fd4179
DT		 4699 case -DLM_EUNLOCK:
4700 receive_flags_reply(lkb, ms);
4701 remove_lock_pc(r, lkb);
4702 queue_cast(r, lkb, -DLM_EUNLOCK);
4703 break;
ef0c2bb0
DT		 4704 case -ENOENT:
4705 break;
e7fd4179 4706 default:
ef0c2bb0
DT		 4707 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4708 lkb->lkb_id, ms->m_result);
e7fd4179 4709 }
ef0c2bb0 4710 out:
e7fd4179
DT		 4711 unlock_rsb(r);
4712 put_rsb(r);
4713}
4714
6d40c4a7 4715static int receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4716{
4717 struct dlm_lkb *lkb;
4718 int error;
4719
4720 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4721 if (error)
4722 return error;
e7fd4179 4723
e7fd4179 4724 _receive_unlock_reply(lkb, ms);
b3f58d8f 4725 dlm_put_lkb(lkb);
6d40c4a7 4726 return 0;
e7fd4179
DT		 4727}
4728
4729static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4730{
4731 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4732 int error;
e7fd4179
DT		 4733
4734 hold_rsb(r);
4735 lock_rsb(r);
4736
c54e04b0
DT		 4737 error = validate_message(lkb, ms);
4738 if (error)
4739 goto out;
4740
ef0c2bb0
DT		 4741 /* stub reply can happen with waiters_mutex held */
4742 error = remove_from_waiters_ms(lkb, ms);
4743 if (error)
4744 goto out;
4745
e7fd4179
DT		 4746 /* this is the value returned from do_cancel() on the master */
4747
ef0c2bb0 4748 switch (ms->m_result) {
e7fd4179
DT		 4749 case -DLM_ECANCEL:
4750 receive_flags_reply(lkb, ms);
4751 revert_lock_pc(r, lkb);
84d8cd69 4752 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 4753 break;
4754 case 0:
e7fd4179
DT		 4755 break;
4756 default:
ef0c2bb0
DT		 4757 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4758 lkb->lkb_id, ms->m_result);
e7fd4179 4759 }
ef0c2bb0 4760 out:
e7fd4179
DT		 4761 unlock_rsb(r);
4762 put_rsb(r);
4763}
4764
6d40c4a7 4765static int receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4766{
4767 struct dlm_lkb *lkb;
4768 int error;
4769
4770 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4771 if (error)
4772 return error;
e7fd4179 4773
e7fd4179 4774 _receive_cancel_reply(lkb, ms);
b3f58d8f 4775 dlm_put_lkb(lkb);
6d40c4a7 4776 return 0;
e7fd4179
DT		 4777}
4778
4779static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
4780{
4781 struct dlm_lkb *lkb;
4782 struct dlm_rsb *r;
4783 int error, ret_nodeid;
c04fecb4 4784 int do_lookup_list = 0;
e7fd4179
DT		 4785
4786 error = find_lkb(ls, ms->m_lkid, &lkb);
4787 if (error) {
6d40c4a7 4788 log_error(ls, "receive_lookup_reply no lkid %x", ms->m_lkid);
e7fd4179
DT		 4789 return;
4790 }
4791
c04fecb4 4792 /* ms->m_result is the value returned by dlm_master_lookup on dir node
e7fd4179 4793 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 4794
4795 r = lkb->lkb_resource;
4796 hold_rsb(r);
4797 lock_rsb(r);
4798
ef0c2bb0
DT		 4799 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4800 if (error)
4801 goto out;
4802
e7fd4179 4803 ret_nodeid = ms->m_nodeid;
c04fecb4
DT		 4804
4805 /* We sometimes receive a request from the dir node for this
4806 rsb before we've received the dir node's loookup_reply for it.
4807 The request from the dir node implies we're the master, so we set
4808 ourself as master in receive_request_reply, and verify here that
4809 we are indeed the master. */
4810
4811 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4812 /* This should never happen */
4813 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4814 "master %d dir %d our %d first %x %s",
4815 lkb->lkb_id, ms->m_header.h_nodeid, ret_nodeid,
4816 r->res_master_nodeid, r->res_dir_nodeid,
4817 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4818 }
4819
e7fd4179 4820 if (ret_nodeid == dlm_our_nodeid()) {
c04fecb4 4821 r->res_master_nodeid = ret_nodeid;
e7fd4179 4822 r->res_nodeid = 0;
c04fecb4 4823 do_lookup_list = 1;
e7fd4179 4824 r->res_first_lkid = 0;
c04fecb4
DT		 4825 } else if (ret_nodeid == -1) {
4826 /* the remote node doesn't believe it's the dir node */
4827 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4828 lkb->lkb_id, ms->m_header.h_nodeid);
4829 r->res_master_nodeid = 0;
4830 r->res_nodeid = -1;
4831 lkb->lkb_nodeid = -1;
e7fd4179 4832 } else {
c04fecb4
DT		 4833 /* set_master() will set lkb_nodeid from r */
4834 r->res_master_nodeid = ret_nodeid;
e7fd4179
DT		 4835 r->res_nodeid = ret_nodeid;
4836 }
4837
ef0c2bb0
DT		 4838 if (is_overlap(lkb)) {
4839 log_debug(ls, "receive_lookup_reply %x unlock %x",
4840 lkb->lkb_id, lkb->lkb_flags);
4841 queue_cast_overlap(r, lkb);
4842 unhold_lkb(lkb); /* undoes create_lkb() */
4843 goto out_list;
4844 }
4845
e7fd4179
DT		 4846 _request_lock(r, lkb);
4847
ef0c2bb0 4848 out_list:
c04fecb4 4849 if (do_lookup_list)
e7fd4179 4850 process_lookup_list(r);
ef0c2bb0 4851 out:
e7fd4179
DT		 4852 unlock_rsb(r);
4853 put_rsb(r);
b3f58d8f 4854 dlm_put_lkb(lkb);
e7fd4179
DT		 4855}
4856
6d40c4a7
DT		 4857static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4858 uint32_t saved_seq)
e7fd4179 4859{
6d40c4a7
DT		 4860 int error = 0, noent = 0;
4861
46b43eed 4862 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
c04fecb4 4863 log_limit(ls, "receive %d from non-member %d %x %x %d",
46b43eed
DT		 4864 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4865 ms->m_remid, ms->m_result);
4866 return;
4867 }
4868
e7fd4179
DT		 4869 switch (ms->m_type) {
4870
4871 /* messages sent to a master node */
4872
4873 case DLM_MSG_REQUEST:
6d40c4a7 4874 error = receive_request(ls, ms);
e7fd4179
DT		 4875 break;
4876
4877 case DLM_MSG_CONVERT:
6d40c4a7 4878 error = receive_convert(ls, ms);
e7fd4179
DT		 4879 break;
4880
4881 case DLM_MSG_UNLOCK:
6d40c4a7 4882 error = receive_unlock(ls, ms);
e7fd4179
DT		 4883 break;
4884
4885 case DLM_MSG_CANCEL:
6d40c4a7
DT		 4886 noent = 1;
4887 error = receive_cancel(ls, ms);
e7fd4179
DT		 4888 break;
4889
4890 /* messages sent from a master node (replies to above) */
4891
4892 case DLM_MSG_REQUEST_REPLY:
6d40c4a7 4893 error = receive_request_reply(ls, ms);
e7fd4179
DT		 4894 break;
4895
4896 case DLM_MSG_CONVERT_REPLY:
6d40c4a7 4897 error = receive_convert_reply(ls, ms);
e7fd4179
DT		 4898 break;
4899
4900 case DLM_MSG_UNLOCK_REPLY:
6d40c4a7 4901 error = receive_unlock_reply(ls, ms);
e7fd4179
DT		 4902 break;
4903
4904 case DLM_MSG_CANCEL_REPLY:
6d40c4a7 4905 error = receive_cancel_reply(ls, ms);
e7fd4179
DT		 4906 break;
4907
4908 /* messages sent from a master node (only two types of async msg) */
4909
4910 case DLM_MSG_GRANT:
6d40c4a7
DT		 4911 noent = 1;
4912 error = receive_grant(ls, ms);
e7fd4179
DT		 4913 break;
4914
4915 case DLM_MSG_BAST:
6d40c4a7
DT		 4916 noent = 1;
4917 error = receive_bast(ls, ms);
e7fd4179
DT		 4918 break;
4919
4920 /* messages sent to a dir node */
4921
4922 case DLM_MSG_LOOKUP:
4923 receive_lookup(ls, ms);
4924 break;
4925
4926 case DLM_MSG_REMOVE:
4927 receive_remove(ls, ms);
4928 break;
4929
4930 /* messages sent from a dir node (remove has no reply) */
4931
4932 case DLM_MSG_LOOKUP_REPLY:
4933 receive_lookup_reply(ls, ms);
4934 break;
4935
8499137d
DT		 4936 /* other messages */
4937
4938 case DLM_MSG_PURGE:
4939 receive_purge(ls, ms);
4940 break;
4941
e7fd4179
DT		 4942 default:
4943 log_error(ls, "unknown message type %d", ms->m_type);
4944 }
6d40c4a7
DT		 4945
4946 /*
4947 * When checking for ENOENT, we're checking the result of
4948 * find_lkb(m_remid):
4949 *
4950 * The lock id referenced in the message wasn't found. This may
4951 * happen in normal usage for the async messages and cancel, so
4952 * only use log_debug for them.
4953 *
4875647a 4954 * Some errors are expected and normal.
6d40c4a7
DT		 4955 */
4956
4957 if (error == -ENOENT && noent) {
4875647a 4958 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4959 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4960 ms->m_lkid, saved_seq);
4961 } else if (error == -ENOENT) {
4875647a 4962 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4963 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4964 ms->m_lkid, saved_seq);
4965
4966 if (ms->m_type == DLM_MSG_CONVERT)
4967 dlm_dump_rsb_hash(ls, ms->m_hash);
4968 }
4875647a
DT		 4969
4970 if (error == -EINVAL) {
4971 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4972 "saved_seq %u",
4973 ms->m_type, ms->m_header.h_nodeid,
4974 ms->m_lkid, ms->m_remid, saved_seq);
4975 }
e7fd4179
DT		 4976}
4977
c36258b5
DT		 4978/* If the lockspace is in recovery mode (locking stopped), then normal
4979 messages are saved on the requestqueue for processing after recovery is
4980 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4981 messages off the requestqueue before we process new ones. This occurs right
4982 after recovery completes when we transition from saving all messages on
4983 requestqueue, to processing all the saved messages, to processing new
4984 messages as they arrive. */
e7fd4179 4985
c36258b5
DT		 4986static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4987 int nodeid)
4988{
4989 if (dlm_locking_stopped(ls)) {
c04fecb4
DT		 4990 /* If we were a member of this lockspace, left, and rejoined,
4991 other nodes may still be sending us messages from the
4992 lockspace generation before we left. */
4993 if (!ls->ls_generation) {
4994 log_limit(ls, "receive %d from %d ignore old gen",
4995 ms->m_type, nodeid);
4996 return;
4997 }
4998
8b0d8e03 4999 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 5000 } else {
5001 dlm_wait_requestqueue(ls);
6d40c4a7 5002 _receive_message(ls, ms, 0);
c36258b5
DT		 5003 }
5004}
5005
5006/* This is called by dlm_recoverd to process messages that were saved on
5007 the requestqueue. */
5008
6d40c4a7
DT		 5009void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
5010 uint32_t saved_seq)
c36258b5 5011{
6d40c4a7 5012 _receive_message(ls, ms, saved_seq);
c36258b5
DT		 5013}
5014
5015/* This is called by the midcomms layer when something is received for
5016 the lockspace. It could be either a MSG (normal message sent as part of
5017 standard locking activity) or an RCOM (recovery message sent as part of
5018 lockspace recovery). */
5019
eef7d739 5020void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 5021{
eef7d739 5022 struct dlm_header *hd = &p->header;
c36258b5
DT		 5023 struct dlm_ls *ls;
5024 int type = 0;
5025
5026 switch (hd->h_cmd) {
5027 case DLM_MSG:
eef7d739
AV		 5028 dlm_message_in(&p->message);
5029 type = p->message.m_type;
c36258b5
DT		 5030 break;
5031 case DLM_RCOM:
eef7d739
AV		 5032 dlm_rcom_in(&p->rcom);
5033 type = p->rcom.rc_type;
c36258b5
DT		 5034 break;
5035 default:
5036 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
5037 return;
5038 }
5039
5040 if (hd->h_nodeid != nodeid) {
5041 log_print("invalid h_nodeid %d from %d lockspace %x",
5042 hd->h_nodeid, nodeid, hd->h_lockspace);
5043 return;
5044 }
5045
5046 ls = dlm_find_lockspace_global(hd->h_lockspace);
5047 if (!ls) {
4875647a
DT		 5048 if (dlm_config.ci_log_debug) {
5049 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
5050 "%u from %d cmd %d type %d\n",
5051 hd->h_lockspace, nodeid, hd->h_cmd, type);
5052 }
c36258b5
DT		 5053
5054 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 5055 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 5056 return;
5057 }
5058
5059 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
5060 be inactive (in this ls) before transitioning to recovery mode */
5061
5062 down_read(&ls->ls_recv_active);
5063 if (hd->h_cmd == DLM_MSG)
eef7d739 5064 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 5065 else
eef7d739 5066 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 5067 up_read(&ls->ls_recv_active);
5068
5069 dlm_put_lockspace(ls);
5070}
e7fd4179 5071
2a7ce0ed
DT		 5072static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
5073 struct dlm_message *ms_stub)
e7fd4179
DT		 5074{
5075 if (middle_conversion(lkb)) {
5076 hold_lkb(lkb);
2a7ce0ed
DT		 5077 memset(ms_stub, 0, sizeof(struct dlm_message));
5078 ms_stub->m_flags = DLM_IFL_STUB_MS;
5079 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
5080 ms_stub->m_result = -EINPROGRESS;
5081 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5082 _receive_convert_reply(lkb, ms_stub);
e7fd4179
DT		 5083
5084 /* Same special case as in receive_rcom_lock_args() */
5085 lkb->lkb_grmode = DLM_LOCK_IV;
5086 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
5087 unhold_lkb(lkb);
5088
5089 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
5090 lkb->lkb_flags |= DLM_IFL_RESEND;
5091 }
5092
5093 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
5094 conversions are async; there's no reply from the remote master */
5095}
5096
5097/* A waiting lkb needs recovery if the master node has failed, or
5098 the master node is changing (only when no directory is used) */
5099
13ef1111
DT		 5100static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
5101 int dir_nodeid)
e7fd4179 5102{
4875647a 5103 if (dlm_no_directory(ls))
13ef1111
DT		 5104 return 1;
5105
4875647a 5106 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
e7fd4179
DT		 5107 return 1;
5108
5109 return 0;
5110}
5111
5112/* Recovery for locks that are waiting for replies from nodes that are now
5113 gone. We can just complete unlocks and cancels by faking a reply from the
5114 dead node. Requests and up-conversions we flag to be resent after
5115 recovery. Down-conversions can just be completed with a fake reply like
5116 unlocks. Conversions between PR and CW need special attention. */
5117
5118void dlm_recover_waiters_pre(struct dlm_ls *ls)
5119{
5120 struct dlm_lkb *lkb, *safe;
2a7ce0ed 5121 struct dlm_message *ms_stub;
601342ce 5122 int wait_type, stub_unlock_result, stub_cancel_result;
13ef1111 5123 int dir_nodeid;
e7fd4179 5124
102e67d4 5125 ms_stub = kmalloc(sizeof(*ms_stub), GFP_KERNEL);
0d37eca7 5126 if (!ms_stub)
2a7ce0ed 5127 return;
2a7ce0ed 5128
90135925 5129 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5130
5131 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
2a7ce0ed 5132
13ef1111
DT		 5133 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
5134
2a7ce0ed
DT		 5135 /* exclude debug messages about unlocks because there can be so
5136 many and they aren't very interesting */
5137
5138 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
13ef1111
DT		 5139 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5140 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
5141 lkb->lkb_id,
5142 lkb->lkb_remid,
5143 lkb->lkb_wait_type,
5144 lkb->lkb_resource->res_nodeid,
5145 lkb->lkb_nodeid,
5146 lkb->lkb_wait_nodeid,
5147 dir_nodeid);
2a7ce0ed 5148 }
e7fd4179
DT		 5149
5150 /* all outstanding lookups, regardless of destination will be
5151 resent after recovery is done */
5152
5153 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
5154 lkb->lkb_flags |= DLM_IFL_RESEND;
5155 continue;
5156 }
5157
13ef1111 5158 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
e7fd4179
DT		 5159 continue;
5160
601342ce
DT		 5161 wait_type = lkb->lkb_wait_type;
5162 stub_unlock_result = -DLM_EUNLOCK;
5163 stub_cancel_result = -DLM_ECANCEL;
5164
5165 /* Main reply may have been received leaving a zero wait_type,
5166 but a reply for the overlapping op may not have been
5167 received. In that case we need to fake the appropriate
5168 reply for the overlap op. */
5169
5170 if (!wait_type) {
5171 if (is_overlap_cancel(lkb)) {
5172 wait_type = DLM_MSG_CANCEL;
5173 if (lkb->lkb_grmode == DLM_LOCK_IV)
5174 stub_cancel_result = 0;
5175 }
5176 if (is_overlap_unlock(lkb)) {
5177 wait_type = DLM_MSG_UNLOCK;
5178 if (lkb->lkb_grmode == DLM_LOCK_IV)
5179 stub_unlock_result = -ENOENT;
5180 }
5181
5182 log_debug(ls, "rwpre overlap %x %x %d %d %d",
5183 lkb->lkb_id, lkb->lkb_flags, wait_type,
5184 stub_cancel_result, stub_unlock_result);
5185 }
5186
5187 switch (wait_type) {
e7fd4179
DT		 5188
5189 case DLM_MSG_REQUEST:
5190 lkb->lkb_flags |= DLM_IFL_RESEND;
5191 break;
5192
5193 case DLM_MSG_CONVERT:
2a7ce0ed 5194 recover_convert_waiter(ls, lkb, ms_stub);
e7fd4179
DT		 5195 break;
5196
5197 case DLM_MSG_UNLOCK:
5198 hold_lkb(lkb);
2a7ce0ed
DT		 5199 memset(ms_stub, 0, sizeof(struct dlm_message));
5200 ms_stub->m_flags = DLM_IFL_STUB_MS;
5201 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
5202 ms_stub->m_result = stub_unlock_result;
5203 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5204 _receive_unlock_reply(lkb, ms_stub);
b3f58d8f 5205 dlm_put_lkb(lkb);
e7fd4179
DT		 5206 break;
5207
5208 case DLM_MSG_CANCEL:
5209 hold_lkb(lkb);
2a7ce0ed
DT		 5210 memset(ms_stub, 0, sizeof(struct dlm_message));
5211 ms_stub->m_flags = DLM_IFL_STUB_MS;
5212 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
5213 ms_stub->m_result = stub_cancel_result;
5214 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5215 _receive_cancel_reply(lkb, ms_stub);
b3f58d8f 5216 dlm_put_lkb(lkb);
e7fd4179
DT		 5217 break;
5218
5219 default:
601342ce
DT		 5220 log_error(ls, "invalid lkb wait_type %d %d",
5221 lkb->lkb_wait_type, wait_type);
e7fd4179 5222 }
81456807 5223 schedule();
e7fd4179 5224 }
90135925 5225 mutex_unlock(&ls->ls_waiters_mutex);
2a7ce0ed 5226 kfree(ms_stub);
e7fd4179
DT		 5227}
5228
ef0c2bb0 5229static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 5230{
5231 struct dlm_lkb *lkb;
ef0c2bb0 5232 int found = 0;
e7fd4179 5233
90135925 5234 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5235 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
5236 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 5237 hold_lkb(lkb);
5238 found = 1;
e7fd4179
DT		 5239 break;
5240 }
5241 }
90135925 5242 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 5243
ef0c2bb0 5244 if (!found)
e7fd4179 5245 lkb = NULL;
ef0c2bb0 5246 return lkb;
e7fd4179
DT		 5247}
5248
5249/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5250 master or dir-node for r. Processing the lkb may result in it being placed
5251 back on waiters. */
5252
ef0c2bb0
DT		 5253/* We do this after normal locking has been enabled and any saved messages
5254 (in requestqueue) have been processed. We should be confident that at
5255 this point we won't get or process a reply to any of these waiting
5256 operations. But, new ops may be coming in on the rsbs/locks here from
5257 userspace or remotely. */
5258
5259/* there may have been an overlap unlock/cancel prior to recovery or after
5260 recovery. if before, the lkb may still have a pos wait_count; if after, the
5261 overlap flag would just have been set and nothing new sent. we can be
5262 confident here than any replies to either the initial op or overlap ops
5263 prior to recovery have been received. */
5264
e7fd4179
DT		 5265int dlm_recover_waiters_post(struct dlm_ls *ls)
5266{
5267 struct dlm_lkb *lkb;
5268 struct dlm_rsb *r;
ef0c2bb0 5269 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 5270
5271 while (1) {
5272 if (dlm_locking_stopped(ls)) {
5273 log_debug(ls, "recover_waiters_post aborted");
5274 error = -EINTR;
5275 break;
5276 }
5277
ef0c2bb0
DT		 5278 lkb = find_resend_waiter(ls);
5279 if (!lkb)
e7fd4179
DT		 5280 break;
5281
5282 r = lkb->lkb_resource;
ef0c2bb0
DT		 5283 hold_rsb(r);
5284 lock_rsb(r);
5285
5286 mstype = lkb->lkb_wait_type;
5287 oc = is_overlap_cancel(lkb);
5288 ou = is_overlap_unlock(lkb);
5289 err = 0;
e7fd4179 5290
13ef1111
DT		 5291 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5292 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5293 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5294 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5295 dlm_dir_nodeid(r), oc, ou);
e7fd4179 5296
ef0c2bb0
DT		 5297 /* At this point we assume that we won't get a reply to any
5298 previous op or overlap op on this lock. First, do a big
5299 remove_from_waiters() for all previous ops. */
5300
5301 lkb->lkb_flags &= ~DLM_IFL_RESEND;
5302 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
5303 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
5304 lkb->lkb_wait_type = 0;
5305 lkb->lkb_wait_count = 0;
5306 mutex_lock(&ls->ls_waiters_mutex);
5307 list_del_init(&lkb->lkb_wait_reply);
5308 mutex_unlock(&ls->ls_waiters_mutex);
5309 unhold_lkb(lkb); /* for waiters list */
5310
5311 if (oc || ou) {
5312 /* do an unlock or cancel instead of resending */
5313 switch (mstype) {
5314 case DLM_MSG_LOOKUP:
5315 case DLM_MSG_REQUEST:
5316 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5317 -DLM_ECANCEL);
5318 unhold_lkb(lkb); /* undoes create_lkb() */
5319 break;
5320 case DLM_MSG_CONVERT:
5321 if (oc) {
5322 queue_cast(r, lkb, -DLM_ECANCEL);
5323 } else {
5324 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5325 _unlock_lock(r, lkb);
5326 }
5327 break;
5328 default:
5329 err = 1;
5330 }
5331 } else {
5332 switch (mstype) {
5333 case DLM_MSG_LOOKUP:
5334 case DLM_MSG_REQUEST:
5335 _request_lock(r, lkb);
5336 if (is_master(r))
5337 confirm_master(r, 0);
5338 break;
5339 case DLM_MSG_CONVERT:
5340 _convert_lock(r, lkb);
5341 break;
5342 default:
5343 err = 1;
5344 }
e7fd4179 5345 }
ef0c2bb0 5346
13ef1111
DT		 5347 if (err) {
5348 log_error(ls, "waiter %x msg %d r_nodeid %d "
5349 "dir_nodeid %d overlap %d %d",
5350 lkb->lkb_id, mstype, r->res_nodeid,
5351 dlm_dir_nodeid(r), oc, ou);
5352 }
ef0c2bb0
DT		 5353 unlock_rsb(r);
5354 put_rsb(r);
5355 dlm_put_lkb(lkb);
e7fd4179
DT		 5356 }
5357
5358 return error;
5359}
5360
4875647a
DT		 5361static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5362 struct list_head *list)
e7fd4179 5363{
e7fd4179
DT		 5364 struct dlm_lkb *lkb, *safe;
5365
4875647a
DT		 5366 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5367 if (!is_master_copy(lkb))
5368 continue;
5369
5370 /* don't purge lkbs we've added in recover_master_copy for
5371 the current recovery seq */
5372
5373 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5374 continue;
5375
5376 del_lkb(r, lkb);
5377
5378 /* this put should free the lkb */
5379 if (!dlm_put_lkb(lkb))
5380 log_error(ls, "purged mstcpy lkb not released");
e7fd4179
DT		 5381 }
5382}
5383
4875647a 5384void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
e7fd4179 5385{
4875647a 5386 struct dlm_ls *ls = r->res_ls;
e7fd4179 5387
4875647a
DT		 5388 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5389 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5390 purge_mstcpy_list(ls, r, &r->res_waitqueue);
e7fd4179
DT		 5391}
5392
4875647a
DT		 5393static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5394 struct list_head *list,
5395 int nodeid_gone, unsigned int *count)
e7fd4179 5396{
4875647a 5397 struct dlm_lkb *lkb, *safe;
e7fd4179 5398
4875647a
DT		 5399 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5400 if (!is_master_copy(lkb))
5401 continue;
5402
5403 if ((lkb->lkb_nodeid == nodeid_gone) ||
5404 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5405
da8c6663
DT		 5406 /* tell recover_lvb to invalidate the lvb
5407 because a node holding EX/PW failed */
5408 if ((lkb->lkb_exflags & DLM_LKF_VALBLK) &&
5409 (lkb->lkb_grmode >= DLM_LOCK_PW)) {
5410 rsb_set_flag(r, RSB_RECOVER_LVB_INVAL);
5411 }
5412
4875647a
DT		 5413 del_lkb(r, lkb);
5414
5415 /* this put should free the lkb */
5416 if (!dlm_put_lkb(lkb))
5417 log_error(ls, "purged dead lkb not released");
5418
5419 rsb_set_flag(r, RSB_RECOVER_GRANT);
5420
5421 (*count)++;
5422 }
5423 }
e7fd4179
DT		 5424}
5425
5426/* Get rid of locks held by nodes that are gone. */
5427
4875647a 5428void dlm_recover_purge(struct dlm_ls *ls)
e7fd4179
DT		 5429{
5430 struct dlm_rsb *r;
4875647a
DT		 5431 struct dlm_member *memb;
5432 int nodes_count = 0;
5433 int nodeid_gone = 0;
5434 unsigned int lkb_count = 0;
5435
5436 /* cache one removed nodeid to optimize the common
5437 case of a single node removed */
5438
5439 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5440 nodes_count++;
5441 nodeid_gone = memb->nodeid;
5442 }
e7fd4179 5443
4875647a
DT		 5444 if (!nodes_count)
5445 return;
e7fd4179
DT		 5446
5447 down_write(&ls->ls_root_sem);
5448 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5449 hold_rsb(r);
5450 lock_rsb(r);
4875647a
DT		 5451 if (is_master(r)) {
5452 purge_dead_list(ls, r, &r->res_grantqueue,
5453 nodeid_gone, &lkb_count);
5454 purge_dead_list(ls, r, &r->res_convertqueue,
5455 nodeid_gone, &lkb_count);
5456 purge_dead_list(ls, r, &r->res_waitqueue,
5457 nodeid_gone, &lkb_count);
5458 }
e7fd4179
DT		 5459 unlock_rsb(r);
5460 unhold_rsb(r);
4875647a 5461 cond_resched();
e7fd4179
DT		 5462 }
5463 up_write(&ls->ls_root_sem);
5464
4875647a 5465 if (lkb_count)
075f0177 5466 log_rinfo(ls, "dlm_recover_purge %u locks for %u nodes",
4875647a 5467 lkb_count, nodes_count);
e7fd4179
DT		 5468}
5469
4875647a 5470static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
97a35d1e 5471{
9beb3bf5 5472 struct rb_node *n;
4875647a 5473 struct dlm_rsb *r;
97a35d1e 5474
c7be761a 5475 spin_lock(&ls->ls_rsbtbl[bucket].lock);
9beb3bf5
BP		 5476 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5477 r = rb_entry(n, struct dlm_rsb, res_hashnode);
4875647a
DT		 5478
5479 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5480 continue;
c503a621
DT		 5481 if (!is_master(r)) {
5482 rsb_clear_flag(r, RSB_RECOVER_GRANT);
97a35d1e 5483 continue;
c503a621 5484 }
97a35d1e 5485 hold_rsb(r);
4875647a
DT		 5486 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5487 return r;
97a35d1e 5488 }
c7be761a 5489 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
4875647a 5490 return NULL;
97a35d1e
DT		 5491}
5492
4875647a
DT		 5493/*
5494 * Attempt to grant locks on resources that we are the master of.
5495 * Locks may have become grantable during recovery because locks
5496 * from departed nodes have been purged (or not rebuilt), allowing
5497 * previously blocked locks to now be granted. The subset of rsb's
5498 * we are interested in are those with lkb's on either the convert or
5499 * waiting queues.
5500 *
5501 * Simplest would be to go through each master rsb and check for non-empty
5502 * convert or waiting queues, and attempt to grant on those rsbs.
5503 * Checking the queues requires lock_rsb, though, for which we'd need
5504 * to release the rsbtbl lock. This would make iterating through all
5505 * rsb's very inefficient. So, we rely on earlier recovery routines
5506 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5507 * locks for.
5508 */
5509
5510void dlm_recover_grant(struct dlm_ls *ls)
e7fd4179
DT		 5511{
5512 struct dlm_rsb *r;
2b4e926a 5513 int bucket = 0;
4875647a
DT		 5514 unsigned int count = 0;
5515 unsigned int rsb_count = 0;
5516 unsigned int lkb_count = 0;
e7fd4179 5517
2b4e926a 5518 while (1) {
4875647a 5519 r = find_grant_rsb(ls, bucket);
2b4e926a
DT		 5520 if (!r) {
5521 if (bucket == ls->ls_rsbtbl_size - 1)
5522 break;
5523 bucket++;
97a35d1e 5524 continue;
2b4e926a 5525 }
4875647a
DT		 5526 rsb_count++;
5527 count = 0;
97a35d1e 5528 lock_rsb(r);
c503a621 5529 /* the RECOVER_GRANT flag is checked in the grant path */
4875647a 5530 grant_pending_locks(r, &count);
c503a621 5531 rsb_clear_flag(r, RSB_RECOVER_GRANT);
4875647a
DT		 5532 lkb_count += count;
5533 confirm_master(r, 0);
97a35d1e
DT		 5534 unlock_rsb(r);
5535 put_rsb(r);
4875647a 5536 cond_resched();
e7fd4179 5537 }
4875647a
DT		 5538
5539 if (lkb_count)
075f0177 5540 log_rinfo(ls, "dlm_recover_grant %u locks on %u resources",
4875647a 5541 lkb_count, rsb_count);
e7fd4179
DT		 5542}
5543
5544static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5545 uint32_t remid)
5546{
5547 struct dlm_lkb *lkb;
5548
5549 list_for_each_entry(lkb, head, lkb_statequeue) {
5550 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5551 return lkb;
5552 }
5553 return NULL;
5554}
5555
5556static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5557 uint32_t remid)
5558{
5559 struct dlm_lkb *lkb;
5560
5561 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5562 if (lkb)
5563 return lkb;
5564 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5565 if (lkb)
5566 return lkb;
5567 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5568 if (lkb)
5569 return lkb;
5570 return NULL;
5571}
5572
ae773d0b 5573/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5574static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5575 struct dlm_rsb *r, struct dlm_rcom *rc)
5576{
5577 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 5578
5579 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 5580 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5581 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5582 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5583 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 5584 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 5585 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 5586 lkb->lkb_rqmode = rl->rl_rqmode;
5587 lkb->lkb_grmode = rl->rl_grmode;
5588 /* don't set lkb_status because add_lkb wants to itself */
5589
8304d6f2
DT		 5590 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5591 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 5592
e7fd4179 5593 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 5594 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
5595 sizeof(struct rcom_lock);
5596 if (lvblen > ls->ls_lvblen)
5597 return -EINVAL;
52bda2b5 5598 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 5599 if (!lkb->lkb_lvbptr)
5600 return -ENOMEM;
e7fd4179
DT		 5601 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5602 }
5603
5604 /* Conversions between PR and CW (middle modes) need special handling.
5605 The real granted mode of these converting locks cannot be determined
5606 until all locks have been rebuilt on the rsb (recover_conversion) */
5607
163a1859
AV		 5608 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5609 middle_conversion(lkb)) {
e7fd4179
DT		 5610 rl->rl_status = DLM_LKSTS_CONVERT;
5611 lkb->lkb_grmode = DLM_LOCK_IV;
5612 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5613 }
5614
5615 return 0;
5616}
5617
5618/* This lkb may have been recovered in a previous aborted recovery so we need
5619 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5620 If so we just send back a standard reply. If not, we create a new lkb with
5621 the given values and send back our lkid. We send back our lkid by sending
5622 back the rcom_lock struct we got but with the remid field filled in. */
5623
ae773d0b 5624/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5625int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5626{
5627 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5628 struct dlm_rsb *r;
5629 struct dlm_lkb *lkb;
6d40c4a7 5630 uint32_t remid = 0;
c04fecb4 5631 int from_nodeid = rc->rc_header.h_nodeid;
e7fd4179
DT		 5632 int error;
5633
5634 if (rl->rl_parent_lkid) {
5635 error = -EOPNOTSUPP;
5636 goto out;
5637 }
5638
6d40c4a7
DT		 5639 remid = le32_to_cpu(rl->rl_lkid);
5640
4875647a
DT		 5641 /* In general we expect the rsb returned to be R_MASTER, but we don't
5642 have to require it. Recovery of masters on one node can overlap
5643 recovery of locks on another node, so one node can send us MSTCPY
5644 locks before we've made ourselves master of this rsb. We can still
5645 add new MSTCPY locks that we receive here without any harm; when
5646 we make ourselves master, dlm_recover_masters() won't touch the
5647 MSTCPY locks we've received early. */
5648
c04fecb4
DT		 5649 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5650 from_nodeid, R_RECEIVE_RECOVER, &r);
e7fd4179
DT		 5651 if (error)
5652 goto out;
5653
c04fecb4
DT		 5654 lock_rsb(r);
5655
4875647a
DT		 5656 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5657 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
c04fecb4 5658 from_nodeid, remid);
4875647a 5659 error = -EBADR;
c04fecb4 5660 goto out_unlock;
4875647a
DT		 5661 }
5662
c04fecb4 5663 lkb = search_remid(r, from_nodeid, remid);
e7fd4179
DT		 5664 if (lkb) {
5665 error = -EEXIST;
5666 goto out_remid;
5667 }
5668
5669 error = create_lkb(ls, &lkb);
5670 if (error)
5671 goto out_unlock;
5672
5673 error = receive_rcom_lock_args(ls, lkb, r, rc);
5674 if (error) {
b3f58d8f 5675 __put_lkb(ls, lkb);
e7fd4179
DT		 5676 goto out_unlock;
5677 }
5678
5679 attach_lkb(r, lkb);
5680 add_lkb(r, lkb, rl->rl_status);
5681 error = 0;
4875647a
DT		 5682 ls->ls_recover_locks_in++;
5683
5684 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5685 rsb_set_flag(r, RSB_RECOVER_GRANT);
e7fd4179
DT		 5686
5687 out_remid:
5688 /* this is the new value returned to the lock holder for
5689 saving in its process-copy lkb */
163a1859 5690 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179 5691
4875647a
DT		 5692 lkb->lkb_recover_seq = ls->ls_recover_seq;
5693
e7fd4179
DT		 5694 out_unlock:
5695 unlock_rsb(r);
5696 put_rsb(r);
5697 out:
6d40c4a7 5698 if (error && error != -EEXIST)
075f0177 5699 log_rinfo(ls, "dlm_recover_master_copy remote %d %x error %d",
c04fecb4 5700 from_nodeid, remid, error);
163a1859 5701 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 5702 return error;
5703}
5704
ae773d0b 5705/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5706int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5707{
5708 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5709 struct dlm_rsb *r;
5710 struct dlm_lkb *lkb;
6d40c4a7
DT		 5711 uint32_t lkid, remid;
5712 int error, result;
5713
5714 lkid = le32_to_cpu(rl->rl_lkid);
5715 remid = le32_to_cpu(rl->rl_remid);
5716 result = le32_to_cpu(rl->rl_result);
e7fd4179 5717
6d40c4a7 5718 error = find_lkb(ls, lkid, &lkb);
e7fd4179 5719 if (error) {
6d40c4a7
DT		 5720 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5721 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5722 return error;
5723 }
5724
4875647a
DT		 5725 r = lkb->lkb_resource;
5726 hold_rsb(r);
5727 lock_rsb(r);
5728
6d40c4a7
DT		 5729 if (!is_process_copy(lkb)) {
5730 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5731 lkid, rc->rc_header.h_nodeid, remid, result);
4875647a
DT		 5732 dlm_dump_rsb(r);
5733 unlock_rsb(r);
5734 put_rsb(r);
5735 dlm_put_lkb(lkb);
6d40c4a7
DT		 5736 return -EINVAL;
5737 }
e7fd4179 5738
6d40c4a7 5739 switch (result) {
dc200a88
DT		 5740 case -EBADR:
5741 /* There's a chance the new master received our lock before
5742 dlm_recover_master_reply(), this wouldn't happen if we did
5743 a barrier between recover_masters and recover_locks. */
6d40c4a7
DT		 5744
5745 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5746 lkid, rc->rc_header.h_nodeid, remid, result);
5747
dc200a88
DT		 5748 dlm_send_rcom_lock(r, lkb);
5749 goto out;
e7fd4179 5750 case -EEXIST:
e7fd4179 5751 case 0:
6d40c4a7 5752 lkb->lkb_remid = remid;
e7fd4179
DT		 5753 break;
5754 default:
6d40c4a7
DT		 5755 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5756 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5757 }
5758
5759 /* an ack for dlm_recover_locks() which waits for replies from
5760 all the locks it sends to new masters */
5761 dlm_recovered_lock(r);
dc200a88 5762 out:
e7fd4179
DT		 5763 unlock_rsb(r);
5764 put_rsb(r);
b3f58d8f 5765 dlm_put_lkb(lkb);
e7fd4179
DT		 5766
5767 return 0;
5768}
5769
597d0cae
DT		 5770int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5771 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 5772 unsigned long timeout_cs)
597d0cae
DT		 5773{
5774 struct dlm_lkb *lkb;
5775 struct dlm_args args;
5776 int error;
5777
85e86edf 5778 dlm_lock_recovery(ls);
597d0cae
DT		 5779
5780 error = create_lkb(ls, &lkb);
5781 if (error) {
5782 kfree(ua);
5783 goto out;
5784 }
5785
5786 if (flags & DLM_LKF_VALBLK) {
573c24c4 5787 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5788 if (!ua->lksb.sb_lvbptr) {
5789 kfree(ua);
5790 __put_lkb(ls, lkb);
5791 error = -ENOMEM;
5792 goto out;
5793 }
5794 }
5795
52bda2b5 5796 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 5797 When DLM_IFL_USER is set, the dlm knows that this is a userspace
5798 lock and that lkb_astparam is the dlm_user_args structure. */
5799
d7db923e 5800 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 5801 fake_astfn, ua, fake_bastfn, &args);
597d0cae 5802 lkb->lkb_flags |= DLM_IFL_USER;
597d0cae
DT		 5803
5804 if (error) {
5805 __put_lkb(ls, lkb);
5806 goto out;
5807 }
5808
5809 error = request_lock(ls, lkb, name, namelen, &args);
5810
5811 switch (error) {
5812 case 0:
5813 break;
5814 case -EINPROGRESS:
5815 error = 0;
5816 break;
5817 case -EAGAIN:
5818 error = 0;
5819 /* fall through */
5820 default:
5821 __put_lkb(ls, lkb);
5822 goto out;
5823 }
5824
5825 /* add this new lkb to the per-process list of locks */
5826 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 5827 hold_lkb(lkb);
597d0cae
DT		 5828 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5829 spin_unlock(&ua->proc->locks_spin);
5830 out:
85e86edf 5831 dlm_unlock_recovery(ls);
597d0cae
DT		 5832 return error;
5833}
5834
5835int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 5836 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
5837 unsigned long timeout_cs)
597d0cae
DT		 5838{
5839 struct dlm_lkb *lkb;
5840 struct dlm_args args;
5841 struct dlm_user_args *ua;
5842 int error;
5843
85e86edf 5844 dlm_lock_recovery(ls);
597d0cae
DT		 5845
5846 error = find_lkb(ls, lkid, &lkb);
5847 if (error)
5848 goto out;
5849
5850 /* user can change the params on its lock when it converts it, or
5851 add an lvb that didn't exist before */
5852
d292c0cc 5853 ua = lkb->lkb_ua;
597d0cae
DT		 5854
5855 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
573c24c4 5856 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5857 if (!ua->lksb.sb_lvbptr) {
5858 error = -ENOMEM;
5859 goto out_put;
5860 }
5861 }
5862 if (lvb_in && ua->lksb.sb_lvbptr)
5863 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5864
d7db923e 5865 ua->xid = ua_tmp->xid;
597d0cae
DT		 5866 ua->castparam = ua_tmp->castparam;
5867 ua->castaddr = ua_tmp->castaddr;
5868 ua->bastparam = ua_tmp->bastparam;
5869 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 5870 ua->user_lksb = ua_tmp->user_lksb;
597d0cae 5871
d7db923e 5872 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 5873 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 5874 if (error)
5875 goto out_put;
5876
5877 error = convert_lock(ls, lkb, &args);
5878
c85d65e9 5879 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 5880 error = 0;
5881 out_put:
5882 dlm_put_lkb(lkb);
5883 out:
85e86edf 5884 dlm_unlock_recovery(ls);
597d0cae
DT		 5885 kfree(ua_tmp);
5886 return error;
5887}
5888
2ab4bd8e
DT		 5889/*
5890 * The caller asks for an orphan lock on a given resource with a given mode.
5891 * If a matching lock exists, it's moved to the owner's list of locks and
5892 * the lkid is returned.
5893 */
5894
5895int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5896 int mode, uint32_t flags, void *name, unsigned int namelen,
5897 unsigned long timeout_cs, uint32_t *lkid)
5898{
5899 struct dlm_lkb *lkb;
5900 struct dlm_user_args *ua;
5901 int found_other_mode = 0;
5902 int found = 0;
5903 int rv = 0;
5904
5905 mutex_lock(&ls->ls_orphans_mutex);
5906 list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) {
5907 if (lkb->lkb_resource->res_length != namelen)
5908 continue;
5909 if (memcmp(lkb->lkb_resource->res_name, name, namelen))
5910 continue;
5911 if (lkb->lkb_grmode != mode) {
5912 found_other_mode = 1;
5913 continue;
5914 }
5915
5916 found = 1;
5917 list_del_init(&lkb->lkb_ownqueue);
5918 lkb->lkb_flags &= ~DLM_IFL_ORPHAN;
5919 *lkid = lkb->lkb_id;
5920 break;
5921 }
5922 mutex_unlock(&ls->ls_orphans_mutex);
5923
5924 if (!found && found_other_mode) {
5925 rv = -EAGAIN;
5926 goto out;
5927 }
5928
5929 if (!found) {
5930 rv = -ENOENT;
5931 goto out;
5932 }
5933
5934 lkb->lkb_exflags = flags;
5935 lkb->lkb_ownpid = (int) current->pid;
5936
5937 ua = lkb->lkb_ua;
5938
5939 ua->proc = ua_tmp->proc;
5940 ua->xid = ua_tmp->xid;
5941 ua->castparam = ua_tmp->castparam;
5942 ua->castaddr = ua_tmp->castaddr;
5943 ua->bastparam = ua_tmp->bastparam;
5944 ua->bastaddr = ua_tmp->bastaddr;
5945 ua->user_lksb = ua_tmp->user_lksb;
5946
5947 /*
5948 * The lkb reference from the ls_orphans list was not
5949 * removed above, and is now considered the reference
5950 * for the proc locks list.
5951 */
5952
5953 spin_lock(&ua->proc->locks_spin);
5954 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5955 spin_unlock(&ua->proc->locks_spin);
5956 out:
5957 kfree(ua_tmp);
5958 return rv;
5959}
5960
597d0cae
DT		 5961int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5962 uint32_t flags, uint32_t lkid, char *lvb_in)
5963{
5964 struct dlm_lkb *lkb;
5965 struct dlm_args args;
5966 struct dlm_user_args *ua;
5967 int error;
5968
85e86edf 5969 dlm_lock_recovery(ls);
597d0cae
DT		 5970
5971 error = find_lkb(ls, lkid, &lkb);
5972 if (error)
5973 goto out;
5974
d292c0cc 5975 ua = lkb->lkb_ua;
597d0cae
DT		 5976
5977 if (lvb_in && ua->lksb.sb_lvbptr)
5978 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 5979 if (ua_tmp->castparam)
5980 ua->castparam = ua_tmp->castparam;
cc346d55 5981 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 5982
5983 error = set_unlock_args(flags, ua, &args);
5984 if (error)
5985 goto out_put;
5986
5987 error = unlock_lock(ls, lkb, &args);
5988
5989 if (error == -DLM_EUNLOCK)
5990 error = 0;
ef0c2bb0
DT		 5991 /* from validate_unlock_args() */
5992 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5993 error = 0;
597d0cae
DT		 5994 if (error)
5995 goto out_put;
5996
5997 spin_lock(&ua->proc->locks_spin);
23e8e1aa 5998 /* dlm_user_add_cb() may have already taken lkb off the proc list */
a1bc86e6
DT		 5999 if (!list_empty(&lkb->lkb_ownqueue))
6000 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 6001 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 6002 out_put:
6003 dlm_put_lkb(lkb);
6004 out:
85e86edf 6005 dlm_unlock_recovery(ls);
ef0c2bb0 6006 kfree(ua_tmp);
597d0cae
DT		 6007 return error;
6008}
6009
6010int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
6011 uint32_t flags, uint32_t lkid)
6012{
6013 struct dlm_lkb *lkb;
6014 struct dlm_args args;
6015 struct dlm_user_args *ua;
6016 int error;
6017
85e86edf 6018 dlm_lock_recovery(ls);
597d0cae
DT		 6019
6020 error = find_lkb(ls, lkid, &lkb);
6021 if (error)
6022 goto out;
6023
d292c0cc 6024 ua = lkb->lkb_ua;
b434eda6
PC		 6025 if (ua_tmp->castparam)
6026 ua->castparam = ua_tmp->castparam;
c059f70e 6027 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 6028
6029 error = set_unlock_args(flags, ua, &args);
6030 if (error)
6031 goto out_put;
6032
6033 error = cancel_lock(ls, lkb, &args);
6034
6035 if (error == -DLM_ECANCEL)
6036 error = 0;
ef0c2bb0
DT		 6037 /* from validate_unlock_args() */
6038 if (error == -EBUSY)
6039 error = 0;
597d0cae
DT		 6040 out_put:
6041 dlm_put_lkb(lkb);
6042 out:
85e86edf 6043 dlm_unlock_recovery(ls);
ef0c2bb0 6044 kfree(ua_tmp);
597d0cae
DT		 6045 return error;
6046}
6047
8b4021fa
DT		 6048int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
6049{
6050 struct dlm_lkb *lkb;
6051 struct dlm_args args;
6052 struct dlm_user_args *ua;
6053 struct dlm_rsb *r;
6054 int error;
6055
6056 dlm_lock_recovery(ls);
6057
6058 error = find_lkb(ls, lkid, &lkb);
6059 if (error)
6060 goto out;
6061
d292c0cc 6062 ua = lkb->lkb_ua;
8b4021fa
DT		 6063
6064 error = set_unlock_args(flags, ua, &args);
6065 if (error)
6066 goto out_put;
6067
6068 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
6069
6070 r = lkb->lkb_resource;
6071 hold_rsb(r);
6072 lock_rsb(r);
6073
6074 error = validate_unlock_args(lkb, &args);
6075 if (error)
6076 goto out_r;
6077 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
6078
6079 error = _cancel_lock(r, lkb);
6080 out_r:
6081 unlock_rsb(r);
6082 put_rsb(r);
6083
6084 if (error == -DLM_ECANCEL)
6085 error = 0;
6086 /* from validate_unlock_args() */
6087 if (error == -EBUSY)
6088 error = 0;
6089 out_put:
6090 dlm_put_lkb(lkb);
6091 out:
6092 dlm_unlock_recovery(ls);
6093 return error;
6094}
6095
ef0c2bb0
DT		 6096/* lkb's that are removed from the waiters list by revert are just left on the
6097 orphans list with the granted orphan locks, to be freed by purge */
6098
597d0cae
DT		 6099static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6100{
ef0c2bb0
DT		 6101 struct dlm_args args;
6102 int error;
597d0cae 6103
2ab4bd8e 6104 hold_lkb(lkb); /* reference for the ls_orphans list */
ef0c2bb0
DT		 6105 mutex_lock(&ls->ls_orphans_mutex);
6106 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
6107 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 6108
d292c0cc 6109 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 6110
6111 error = cancel_lock(ls, lkb, &args);
6112 if (error == -DLM_ECANCEL)
6113 error = 0;
6114 return error;
597d0cae
DT		 6115}
6116
da8c6663
DT		 6117/* The FORCEUNLOCK flag allows the unlock to go ahead even if the lkb isn't
6118 granted. Regardless of what rsb queue the lock is on, it's removed and
6119 freed. The IVVALBLK flag causes the lvb on the resource to be invalidated
6120 if our lock is PW/EX (it's ignored if our granted mode is smaller.) */
597d0cae
DT		 6121
6122static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6123{
597d0cae
DT		 6124 struct dlm_args args;
6125 int error;
6126
da8c6663
DT		 6127 set_unlock_args(DLM_LKF_FORCEUNLOCK | DLM_LKF_IVVALBLK,
6128 lkb->lkb_ua, &args);
597d0cae
DT		 6129
6130 error = unlock_lock(ls, lkb, &args);
6131 if (error == -DLM_EUNLOCK)
6132 error = 0;
6133 return error;
6134}
6135
ef0c2bb0
DT		 6136/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
6137 (which does lock_rsb) due to deadlock with receiving a message that does
23e8e1aa 6138 lock_rsb followed by dlm_user_add_cb() */
ef0c2bb0
DT		 6139
6140static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
6141 struct dlm_user_proc *proc)
6142{
6143 struct dlm_lkb *lkb = NULL;
6144
6145 mutex_lock(&ls->ls_clear_proc_locks);
6146 if (list_empty(&proc->locks))
6147 goto out;
6148
6149 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
6150 list_del_init(&lkb->lkb_ownqueue);
6151
6152 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6153 lkb->lkb_flags |= DLM_IFL_ORPHAN;
6154 else
6155 lkb->lkb_flags |= DLM_IFL_DEAD;
6156 out:
6157 mutex_unlock(&ls->ls_clear_proc_locks);
6158 return lkb;
6159}
6160
23e8e1aa 6161/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
597d0cae
DT		 6162 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
6163 which we clear here. */
6164
6165/* proc CLOSING flag is set so no more device_reads should look at proc->asts
6166 list, and no more device_writes should add lkb's to proc->locks list; so we
6167 shouldn't need to take asts_spin or locks_spin here. this assumes that
6168 device reads/writes/closes are serialized -- FIXME: we may need to serialize
6169 them ourself. */
6170
6171void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6172{
6173 struct dlm_lkb *lkb, *safe;
6174
85e86edf 6175 dlm_lock_recovery(ls);
597d0cae 6176
ef0c2bb0
DT		 6177 while (1) {
6178 lkb = del_proc_lock(ls, proc);
6179 if (!lkb)
6180 break;
84d8cd69 6181 del_timeout(lkb);
ef0c2bb0 6182 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 6183 orphan_proc_lock(ls, lkb);
ef0c2bb0 6184 else
597d0cae 6185 unlock_proc_lock(ls, lkb);
597d0cae
DT		 6186
6187 /* this removes the reference for the proc->locks list
6188 added by dlm_user_request, it may result in the lkb
6189 being freed */
6190
6191 dlm_put_lkb(lkb);
6192 }
a1bc86e6 6193
ef0c2bb0
DT		 6194 mutex_lock(&ls->ls_clear_proc_locks);
6195
a1bc86e6
DT		 6196 /* in-progress unlocks */
6197 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6198 list_del_init(&lkb->lkb_ownqueue);
6199 lkb->lkb_flags |= DLM_IFL_DEAD;
6200 dlm_put_lkb(lkb);
6201 }
6202
23e8e1aa 6203 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6204 memset(&lkb->lkb_callbacks, 0,
6205 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6206 list_del_init(&lkb->lkb_cb_list);
a1bc86e6
DT		 6207 dlm_put_lkb(lkb);
6208 }
6209
597d0cae 6210 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 6211 dlm_unlock_recovery(ls);
597d0cae 6212}
a1bc86e6 6213
8499137d
DT		 6214static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6215{
6216 struct dlm_lkb *lkb, *safe;
6217
6218 while (1) {
6219 lkb = NULL;
6220 spin_lock(&proc->locks_spin);
6221 if (!list_empty(&proc->locks)) {
6222 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6223 lkb_ownqueue);
6224 list_del_init(&lkb->lkb_ownqueue);
6225 }
6226 spin_unlock(&proc->locks_spin);
6227
6228 if (!lkb)
6229 break;
6230
6231 lkb->lkb_flags |= DLM_IFL_DEAD;
6232 unlock_proc_lock(ls, lkb);
6233 dlm_put_lkb(lkb); /* ref from proc->locks list */
6234 }
6235
6236 spin_lock(&proc->locks_spin);
6237 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6238 list_del_init(&lkb->lkb_ownqueue);
6239 lkb->lkb_flags |= DLM_IFL_DEAD;
6240 dlm_put_lkb(lkb);
6241 }
6242 spin_unlock(&proc->locks_spin);
6243
6244 spin_lock(&proc->asts_spin);
23e8e1aa 6245 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6246 memset(&lkb->lkb_callbacks, 0,
6247 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6248 list_del_init(&lkb->lkb_cb_list);
8499137d
DT		 6249 dlm_put_lkb(lkb);
6250 }
6251 spin_unlock(&proc->asts_spin);
6252}
6253
6254/* pid of 0 means purge all orphans */
6255
6256static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6257{
6258 struct dlm_lkb *lkb, *safe;
6259
6260 mutex_lock(&ls->ls_orphans_mutex);
6261 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6262 if (pid && lkb->lkb_ownpid != pid)
6263 continue;
6264 unlock_proc_lock(ls, lkb);
6265 list_del_init(&lkb->lkb_ownqueue);
6266 dlm_put_lkb(lkb);
6267 }
6268 mutex_unlock(&ls->ls_orphans_mutex);
6269}
6270
6271static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6272{
6273 struct dlm_message *ms;
6274 struct dlm_mhandle *mh;
6275 int error;
6276
6277 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6278 DLM_MSG_PURGE, &ms, &mh);
6279 if (error)
6280 return error;
6281 ms->m_nodeid = nodeid;
6282 ms->m_pid = pid;
6283
6284 return send_message(mh, ms);
6285}
6286
6287int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6288 int nodeid, int pid)
6289{
6290 int error = 0;
6291
2ab4bd8e 6292 if (nodeid && (nodeid != dlm_our_nodeid())) {
8499137d
DT		 6293 error = send_purge(ls, nodeid, pid);
6294 } else {
85e86edf 6295 dlm_lock_recovery(ls);
8499137d
DT		 6296 if (pid == current->pid)
6297 purge_proc_locks(ls, proc);
6298 else
6299 do_purge(ls, nodeid, pid);
85e86edf 6300 dlm_unlock_recovery(ls);
8499137d
DT		 6301 }
6302 return error;
6303}
6304
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