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David Teiglande7fd4172006-01-18 09:30:29 +00001/******************************************************************************
2*******************************************************************************
3**
4** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
David Teigland7fe2b312010-02-24 11:08:18 -06005** Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
David Teiglande7fd4172006-01-18 09:30:29 +00006**
7** This copyrighted material is made available to anyone wishing to use,
8** modify, copy, or redistribute it subject to the terms and conditions
9** of the GNU General Public License v.2.
10**
11*******************************************************************************
12******************************************************************************/
13
14#include "dlm_internal.h"
15#include "lock.h"
David Teigland597d0ca2006-07-12 16:44:04 -050016#include "user.h"
David Teiglande7fd4172006-01-18 09:30:29 +000017
David Teigland6ad22912012-08-02 11:00:05 -050018static uint64_t dlm_cb_seq;
19static DEFINE_SPINLOCK(dlm_cb_seq_spin);
David Teiglande7fd4172006-01-18 09:30:29 +000020
David Teigland8304d6f2011-02-21 14:58:21 -060021static void dlm_dump_lkb_callbacks(struct dlm_lkb *lkb)
22{
23 int i;
24
25 log_print("last_bast %x %llu flags %x mode %d sb %d %x",
26 lkb->lkb_id,
27 (unsigned long long)lkb->lkb_last_bast.seq,
28 lkb->lkb_last_bast.flags,
29 lkb->lkb_last_bast.mode,
30 lkb->lkb_last_bast.sb_status,
31 lkb->lkb_last_bast.sb_flags);
32
33 log_print("last_cast %x %llu flags %x mode %d sb %d %x",
34 lkb->lkb_id,
35 (unsigned long long)lkb->lkb_last_cast.seq,
36 lkb->lkb_last_cast.flags,
37 lkb->lkb_last_cast.mode,
38 lkb->lkb_last_cast.sb_status,
39 lkb->lkb_last_cast.sb_flags);
40
41 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
42 log_print("cb %x %llu flags %x mode %d sb %d %x",
43 lkb->lkb_id,
44 (unsigned long long)lkb->lkb_callbacks[i].seq,
45 lkb->lkb_callbacks[i].flags,
46 lkb->lkb_callbacks[i].mode,
47 lkb->lkb_callbacks[i].sb_status,
48 lkb->lkb_callbacks[i].sb_flags);
49 }
50}
51
David Teigland8304d6f2011-02-21 14:58:21 -060052int dlm_add_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
53 int status, uint32_t sbflags, uint64_t seq)
David Teiglande7fd4172006-01-18 09:30:29 +000054{
David Teigland8304d6f2011-02-21 14:58:21 -060055 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
56 uint64_t prev_seq;
57 int prev_mode;
David Teigland23e8e1a2011-04-05 13:16:24 -050058 int i, rv;
David Teigland8304d6f2011-02-21 14:58:21 -060059
60 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
61 if (lkb->lkb_callbacks[i].seq)
62 continue;
63
64 /*
65 * Suppress some redundant basts here, do more on removal.
66 * Don't even add a bast if the callback just before it
67 * is a bast for the same mode or a more restrictive mode.
68 * (the addional > PR check is needed for PR/CW inversion)
69 */
70
71 if ((i > 0) && (flags & DLM_CB_BAST) &&
72 (lkb->lkb_callbacks[i-1].flags & DLM_CB_BAST)) {
73
74 prev_seq = lkb->lkb_callbacks[i-1].seq;
75 prev_mode = lkb->lkb_callbacks[i-1].mode;
76
77 if ((prev_mode == mode) ||
78 (prev_mode > mode && prev_mode > DLM_LOCK_PR)) {
79
80 log_debug(ls, "skip %x add bast %llu mode %d "
81 "for bast %llu mode %d",
82 lkb->lkb_id,
83 (unsigned long long)seq,
84 mode,
85 (unsigned long long)prev_seq,
86 prev_mode);
David Teigland23e8e1a2011-04-05 13:16:24 -050087 rv = 0;
88 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -060089 }
90 }
91
92 lkb->lkb_callbacks[i].seq = seq;
93 lkb->lkb_callbacks[i].flags = flags;
94 lkb->lkb_callbacks[i].mode = mode;
95 lkb->lkb_callbacks[i].sb_status = status;
96 lkb->lkb_callbacks[i].sb_flags = (sbflags & 0x000000FF);
David Teigland23e8e1a2011-04-05 13:16:24 -050097 rv = 0;
David Teigland8304d6f2011-02-21 14:58:21 -060098 break;
99 }
100
101 if (i == DLM_CALLBACKS_SIZE) {
102 log_error(ls, "no callbacks %x %llu flags %x mode %d sb %d %x",
103 lkb->lkb_id, (unsigned long long)seq,
104 flags, mode, status, sbflags);
105 dlm_dump_lkb_callbacks(lkb);
David Teigland23e8e1a2011-04-05 13:16:24 -0500106 rv = -1;
107 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -0600108 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500109 out:
110 return rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600111}
112
113int dlm_rem_lkb_callback(struct dlm_ls *ls, struct dlm_lkb *lkb,
114 struct dlm_callback *cb, int *resid)
115{
David Teigland23e8e1a2011-04-05 13:16:24 -0500116 int i, rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600117
118 *resid = 0;
119
David Teigland23e8e1a2011-04-05 13:16:24 -0500120 if (!lkb->lkb_callbacks[0].seq) {
121 rv = -ENOENT;
122 goto out;
123 }
David Teigland8304d6f2011-02-21 14:58:21 -0600124
125 /* oldest undelivered cb is callbacks[0] */
126
127 memcpy(cb, &lkb->lkb_callbacks[0], sizeof(struct dlm_callback));
128 memset(&lkb->lkb_callbacks[0], 0, sizeof(struct dlm_callback));
129
130 /* shift others down */
131
132 for (i = 1; i < DLM_CALLBACKS_SIZE; i++) {
133 if (!lkb->lkb_callbacks[i].seq)
134 break;
135 memcpy(&lkb->lkb_callbacks[i-1], &lkb->lkb_callbacks[i],
136 sizeof(struct dlm_callback));
137 memset(&lkb->lkb_callbacks[i], 0, sizeof(struct dlm_callback));
138 (*resid)++;
139 }
140
141 /* if cb is a bast, it should be skipped if the blocking mode is
142 compatible with the last granted mode */
143
144 if ((cb->flags & DLM_CB_BAST) && lkb->lkb_last_cast.seq) {
145 if (dlm_modes_compat(cb->mode, lkb->lkb_last_cast.mode)) {
146 cb->flags |= DLM_CB_SKIP;
147
148 log_debug(ls, "skip %x bast %llu mode %d "
149 "for cast %llu mode %d",
150 lkb->lkb_id,
151 (unsigned long long)cb->seq,
152 cb->mode,
153 (unsigned long long)lkb->lkb_last_cast.seq,
154 lkb->lkb_last_cast.mode);
David Teigland23e8e1a2011-04-05 13:16:24 -0500155 rv = 0;
156 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -0600157 }
158 }
159
160 if (cb->flags & DLM_CB_CAST) {
161 memcpy(&lkb->lkb_last_cast, cb, sizeof(struct dlm_callback));
162 lkb->lkb_last_cast_time = ktime_get();
163 }
164
165 if (cb->flags & DLM_CB_BAST) {
166 memcpy(&lkb->lkb_last_bast, cb, sizeof(struct dlm_callback));
167 lkb->lkb_last_bast_time = ktime_get();
168 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500169 rv = 0;
170 out:
171 return rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600172}
173
David Teigland23e8e1a2011-04-05 13:16:24 -0500174void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
175 uint32_t sbflags)
David Teigland8304d6f2011-02-21 14:58:21 -0600176{
David Teigland23e8e1a2011-04-05 13:16:24 -0500177 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
178 uint64_t new_seq, prev_seq;
David Teigland8304d6f2011-02-21 14:58:21 -0600179 int rv;
180
David Teigland23e8e1a2011-04-05 13:16:24 -0500181 spin_lock(&dlm_cb_seq_spin);
182 new_seq = ++dlm_cb_seq;
183 spin_unlock(&dlm_cb_seq_spin);
David Teigland8304d6f2011-02-21 14:58:21 -0600184
David Teigland597d0ca2006-07-12 16:44:04 -0500185 if (lkb->lkb_flags & DLM_IFL_USER) {
David Teigland23e8e1a2011-04-05 13:16:24 -0500186 dlm_user_add_ast(lkb, flags, mode, status, sbflags, new_seq);
David Teigland597d0ca2006-07-12 16:44:04 -0500187 return;
188 }
189
David Teigland23e8e1a2011-04-05 13:16:24 -0500190 mutex_lock(&lkb->lkb_cb_mutex);
191 prev_seq = lkb->lkb_callbacks[0].seq;
David Teigland7fe2b312010-02-24 11:08:18 -0600192
David Teigland23e8e1a2011-04-05 13:16:24 -0500193 rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, new_seq);
194 if (rv < 0)
195 goto out;
196
197 if (!prev_seq) {
David Teigland8304d6f2011-02-21 14:58:21 -0600198 kref_get(&lkb->lkb_ref);
David Teiglande7fd4172006-01-18 09:30:29 +0000199
David Teigland23e8e1a2011-04-05 13:16:24 -0500200 if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
201 mutex_lock(&ls->ls_cb_mutex);
202 list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
203 mutex_unlock(&ls->ls_cb_mutex);
204 } else {
205 queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
206 }
207 }
208 out:
209 mutex_unlock(&lkb->lkb_cb_mutex);
David Teiglande7fd4172006-01-18 09:30:29 +0000210}
211
David Teigland23e8e1a2011-04-05 13:16:24 -0500212void dlm_callback_work(struct work_struct *work)
David Teiglande7fd4172006-01-18 09:30:29 +0000213{
David Teigland23e8e1a2011-04-05 13:16:24 -0500214 struct dlm_lkb *lkb = container_of(work, struct dlm_lkb, lkb_cb_work);
215 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
David Teigland7fe2b312010-02-24 11:08:18 -0600216 void (*castfn) (void *astparam);
217 void (*bastfn) (void *astparam, int mode);
David Teigland8304d6f2011-02-21 14:58:21 -0600218 struct dlm_callback callbacks[DLM_CALLBACKS_SIZE];
219 int i, rv, resid;
David Teiglande7fd4172006-01-18 09:30:29 +0000220
David Teigland23e8e1a2011-04-05 13:16:24 -0500221 memset(&callbacks, 0, sizeof(callbacks));
David Teiglande7fd4172006-01-18 09:30:29 +0000222
David Teigland23e8e1a2011-04-05 13:16:24 -0500223 mutex_lock(&lkb->lkb_cb_mutex);
224 if (!lkb->lkb_callbacks[0].seq) {
225 /* no callback work exists, shouldn't happen */
226 log_error(ls, "dlm_callback_work %x no work", lkb->lkb_id);
227 dlm_print_lkb(lkb);
228 dlm_dump_lkb_callbacks(lkb);
David Teiglande7fd4172006-01-18 09:30:29 +0000229 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500230
231 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
232 rv = dlm_rem_lkb_callback(ls, lkb, &callbacks[i], &resid);
233 if (rv < 0)
234 break;
235 }
236
237 if (resid) {
238 /* cbs remain, loop should have removed all, shouldn't happen */
239 log_error(ls, "dlm_callback_work %x resid %d", lkb->lkb_id,
240 resid);
241 dlm_print_lkb(lkb);
242 dlm_dump_lkb_callbacks(lkb);
243 }
244 mutex_unlock(&lkb->lkb_cb_mutex);
245
246 castfn = lkb->lkb_astfn;
247 bastfn = lkb->lkb_bastfn;
248
249 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
250 if (!callbacks[i].seq)
251 break;
252 if (callbacks[i].flags & DLM_CB_SKIP) {
253 continue;
254 } else if (callbacks[i].flags & DLM_CB_BAST) {
255 bastfn(lkb->lkb_astparam, callbacks[i].mode);
256 } else if (callbacks[i].flags & DLM_CB_CAST) {
257 lkb->lkb_lksb->sb_status = callbacks[i].sb_status;
258 lkb->lkb_lksb->sb_flags = callbacks[i].sb_flags;
259 castfn(lkb->lkb_astparam);
260 }
261 }
262
263 /* undo kref_get from dlm_add_callback, may cause lkb to be freed */
264 dlm_put_lkb(lkb);
David Teiglande7fd4172006-01-18 09:30:29 +0000265}
266
David Teigland23e8e1a2011-04-05 13:16:24 -0500267int dlm_callback_start(struct dlm_ls *ls)
David Teiglande7fd4172006-01-18 09:30:29 +0000268{
David Teigland23e8e1a2011-04-05 13:16:24 -0500269 ls->ls_callback_wq = alloc_workqueue("dlm_callback",
Tejun Heoededf302013-07-30 08:40:24 -0400270 WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
David Teigland23e8e1a2011-04-05 13:16:24 -0500271 if (!ls->ls_callback_wq) {
272 log_print("can't start dlm_callback workqueue");
273 return -ENOMEM;
David Teiglande7fd4172006-01-18 09:30:29 +0000274 }
275 return 0;
276}
277
David Teigland23e8e1a2011-04-05 13:16:24 -0500278void dlm_callback_stop(struct dlm_ls *ls)
David Teiglande7fd4172006-01-18 09:30:29 +0000279{
David Teigland23e8e1a2011-04-05 13:16:24 -0500280 if (ls->ls_callback_wq)
281 destroy_workqueue(ls->ls_callback_wq);
282}
283
284void dlm_callback_suspend(struct dlm_ls *ls)
285{
286 set_bit(LSFL_CB_DELAY, &ls->ls_flags);
287
288 if (ls->ls_callback_wq)
289 flush_workqueue(ls->ls_callback_wq);
290}
291
292void dlm_callback_resume(struct dlm_ls *ls)
293{
294 struct dlm_lkb *lkb, *safe;
295 int count = 0;
296
297 clear_bit(LSFL_CB_DELAY, &ls->ls_flags);
298
299 if (!ls->ls_callback_wq)
300 return;
301
302 mutex_lock(&ls->ls_cb_mutex);
303 list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
304 list_del_init(&lkb->lkb_cb_list);
305 queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
306 count++;
David Teiglande7fd4172006-01-18 09:30:29 +0000307 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500308 mutex_unlock(&ls->ls_cb_mutex);
David Teiglande7fd4172006-01-18 09:30:29 +0000309
David Teigland48756472012-04-26 15:54:29 -0500310 if (count)
311 log_debug(ls, "dlm_callback_resume %d", count);
David Teiglande7fd4172006-01-18 09:30:29 +0000312}
313