blob: dcea1e37a1b7342ee78d245e7398809620d8e789 [file] [log] [blame]
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"
Rashika Kheria95058572014-02-09 18:19:17 +053017#include "ast.h"
David Teiglande7fd4172006-01-18 09:30:29 +000018
David Teigland6ad22912012-08-02 11:00:05 -050019static uint64_t dlm_cb_seq;
20static DEFINE_SPINLOCK(dlm_cb_seq_spin);
David Teiglande7fd4172006-01-18 09:30:29 +000021
David Teigland8304d6f2011-02-21 14:58:21 -060022static void dlm_dump_lkb_callbacks(struct dlm_lkb *lkb)
23{
24 int i;
25
26 log_print("last_bast %x %llu flags %x mode %d sb %d %x",
27 lkb->lkb_id,
28 (unsigned long long)lkb->lkb_last_bast.seq,
29 lkb->lkb_last_bast.flags,
30 lkb->lkb_last_bast.mode,
31 lkb->lkb_last_bast.sb_status,
32 lkb->lkb_last_bast.sb_flags);
33
34 log_print("last_cast %x %llu flags %x mode %d sb %d %x",
35 lkb->lkb_id,
36 (unsigned long long)lkb->lkb_last_cast.seq,
37 lkb->lkb_last_cast.flags,
38 lkb->lkb_last_cast.mode,
39 lkb->lkb_last_cast.sb_status,
40 lkb->lkb_last_cast.sb_flags);
41
42 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
43 log_print("cb %x %llu flags %x mode %d sb %d %x",
44 lkb->lkb_id,
45 (unsigned long long)lkb->lkb_callbacks[i].seq,
46 lkb->lkb_callbacks[i].flags,
47 lkb->lkb_callbacks[i].mode,
48 lkb->lkb_callbacks[i].sb_status,
49 lkb->lkb_callbacks[i].sb_flags);
50 }
51}
52
David Teigland8304d6f2011-02-21 14:58:21 -060053int dlm_add_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
54 int status, uint32_t sbflags, uint64_t seq)
David Teiglande7fd4172006-01-18 09:30:29 +000055{
David Teigland8304d6f2011-02-21 14:58:21 -060056 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
57 uint64_t prev_seq;
58 int prev_mode;
David Teigland23e8e1a2011-04-05 13:16:24 -050059 int i, rv;
David Teigland8304d6f2011-02-21 14:58:21 -060060
61 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
62 if (lkb->lkb_callbacks[i].seq)
63 continue;
64
65 /*
66 * Suppress some redundant basts here, do more on removal.
67 * Don't even add a bast if the callback just before it
68 * is a bast for the same mode or a more restrictive mode.
69 * (the addional > PR check is needed for PR/CW inversion)
70 */
71
72 if ((i > 0) && (flags & DLM_CB_BAST) &&
73 (lkb->lkb_callbacks[i-1].flags & DLM_CB_BAST)) {
74
75 prev_seq = lkb->lkb_callbacks[i-1].seq;
76 prev_mode = lkb->lkb_callbacks[i-1].mode;
77
78 if ((prev_mode == mode) ||
79 (prev_mode > mode && prev_mode > DLM_LOCK_PR)) {
80
81 log_debug(ls, "skip %x add bast %llu mode %d "
82 "for bast %llu mode %d",
83 lkb->lkb_id,
84 (unsigned long long)seq,
85 mode,
86 (unsigned long long)prev_seq,
87 prev_mode);
David Teigland23e8e1a2011-04-05 13:16:24 -050088 rv = 0;
89 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -060090 }
91 }
92
93 lkb->lkb_callbacks[i].seq = seq;
94 lkb->lkb_callbacks[i].flags = flags;
95 lkb->lkb_callbacks[i].mode = mode;
96 lkb->lkb_callbacks[i].sb_status = status;
97 lkb->lkb_callbacks[i].sb_flags = (sbflags & 0x000000FF);
David Teigland23e8e1a2011-04-05 13:16:24 -050098 rv = 0;
David Teigland8304d6f2011-02-21 14:58:21 -060099 break;
100 }
101
102 if (i == DLM_CALLBACKS_SIZE) {
103 log_error(ls, "no callbacks %x %llu flags %x mode %d sb %d %x",
104 lkb->lkb_id, (unsigned long long)seq,
105 flags, mode, status, sbflags);
106 dlm_dump_lkb_callbacks(lkb);
David Teigland23e8e1a2011-04-05 13:16:24 -0500107 rv = -1;
108 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -0600109 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500110 out:
111 return rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600112}
113
114int dlm_rem_lkb_callback(struct dlm_ls *ls, struct dlm_lkb *lkb,
115 struct dlm_callback *cb, int *resid)
116{
David Teigland23e8e1a2011-04-05 13:16:24 -0500117 int i, rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600118
119 *resid = 0;
120
David Teigland23e8e1a2011-04-05 13:16:24 -0500121 if (!lkb->lkb_callbacks[0].seq) {
122 rv = -ENOENT;
123 goto out;
124 }
David Teigland8304d6f2011-02-21 14:58:21 -0600125
126 /* oldest undelivered cb is callbacks[0] */
127
128 memcpy(cb, &lkb->lkb_callbacks[0], sizeof(struct dlm_callback));
129 memset(&lkb->lkb_callbacks[0], 0, sizeof(struct dlm_callback));
130
131 /* shift others down */
132
133 for (i = 1; i < DLM_CALLBACKS_SIZE; i++) {
134 if (!lkb->lkb_callbacks[i].seq)
135 break;
136 memcpy(&lkb->lkb_callbacks[i-1], &lkb->lkb_callbacks[i],
137 sizeof(struct dlm_callback));
138 memset(&lkb->lkb_callbacks[i], 0, sizeof(struct dlm_callback));
139 (*resid)++;
140 }
141
142 /* if cb is a bast, it should be skipped if the blocking mode is
143 compatible with the last granted mode */
144
145 if ((cb->flags & DLM_CB_BAST) && lkb->lkb_last_cast.seq) {
146 if (dlm_modes_compat(cb->mode, lkb->lkb_last_cast.mode)) {
147 cb->flags |= DLM_CB_SKIP;
148
149 log_debug(ls, "skip %x bast %llu mode %d "
150 "for cast %llu mode %d",
151 lkb->lkb_id,
152 (unsigned long long)cb->seq,
153 cb->mode,
154 (unsigned long long)lkb->lkb_last_cast.seq,
155 lkb->lkb_last_cast.mode);
David Teigland23e8e1a2011-04-05 13:16:24 -0500156 rv = 0;
157 goto out;
David Teigland8304d6f2011-02-21 14:58:21 -0600158 }
159 }
160
161 if (cb->flags & DLM_CB_CAST) {
162 memcpy(&lkb->lkb_last_cast, cb, sizeof(struct dlm_callback));
163 lkb->lkb_last_cast_time = ktime_get();
164 }
165
166 if (cb->flags & DLM_CB_BAST) {
167 memcpy(&lkb->lkb_last_bast, cb, sizeof(struct dlm_callback));
168 lkb->lkb_last_bast_time = ktime_get();
169 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500170 rv = 0;
171 out:
172 return rv;
David Teigland8304d6f2011-02-21 14:58:21 -0600173}
174
David Teigland23e8e1a2011-04-05 13:16:24 -0500175void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
176 uint32_t sbflags)
David Teigland8304d6f2011-02-21 14:58:21 -0600177{
David Teigland23e8e1a2011-04-05 13:16:24 -0500178 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
179 uint64_t new_seq, prev_seq;
David Teigland8304d6f2011-02-21 14:58:21 -0600180 int rv;
181
David Teigland23e8e1a2011-04-05 13:16:24 -0500182 spin_lock(&dlm_cb_seq_spin);
183 new_seq = ++dlm_cb_seq;
184 spin_unlock(&dlm_cb_seq_spin);
David Teigland8304d6f2011-02-21 14:58:21 -0600185
David Teigland597d0ca2006-07-12 16:44:04 -0500186 if (lkb->lkb_flags & DLM_IFL_USER) {
David Teigland23e8e1a2011-04-05 13:16:24 -0500187 dlm_user_add_ast(lkb, flags, mode, status, sbflags, new_seq);
David Teigland597d0ca2006-07-12 16:44:04 -0500188 return;
189 }
190
David Teigland23e8e1a2011-04-05 13:16:24 -0500191 mutex_lock(&lkb->lkb_cb_mutex);
192 prev_seq = lkb->lkb_callbacks[0].seq;
David Teigland7fe2b312010-02-24 11:08:18 -0600193
David Teigland23e8e1a2011-04-05 13:16:24 -0500194 rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, new_seq);
195 if (rv < 0)
196 goto out;
197
198 if (!prev_seq) {
David Teigland8304d6f2011-02-21 14:58:21 -0600199 kref_get(&lkb->lkb_ref);
David Teiglande7fd4172006-01-18 09:30:29 +0000200
David Teigland23e8e1a2011-04-05 13:16:24 -0500201 if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
202 mutex_lock(&ls->ls_cb_mutex);
203 list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
204 mutex_unlock(&ls->ls_cb_mutex);
205 } else {
206 queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
207 }
208 }
209 out:
210 mutex_unlock(&lkb->lkb_cb_mutex);
David Teiglande7fd4172006-01-18 09:30:29 +0000211}
212
David Teigland23e8e1a2011-04-05 13:16:24 -0500213void dlm_callback_work(struct work_struct *work)
David Teiglande7fd4172006-01-18 09:30:29 +0000214{
David Teigland23e8e1a2011-04-05 13:16:24 -0500215 struct dlm_lkb *lkb = container_of(work, struct dlm_lkb, lkb_cb_work);
216 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
David Teigland7fe2b312010-02-24 11:08:18 -0600217 void (*castfn) (void *astparam);
218 void (*bastfn) (void *astparam, int mode);
David Teigland8304d6f2011-02-21 14:58:21 -0600219 struct dlm_callback callbacks[DLM_CALLBACKS_SIZE];
220 int i, rv, resid;
David Teiglande7fd4172006-01-18 09:30:29 +0000221
David Teigland23e8e1a2011-04-05 13:16:24 -0500222 memset(&callbacks, 0, sizeof(callbacks));
David Teiglande7fd4172006-01-18 09:30:29 +0000223
David Teigland23e8e1a2011-04-05 13:16:24 -0500224 mutex_lock(&lkb->lkb_cb_mutex);
225 if (!lkb->lkb_callbacks[0].seq) {
226 /* no callback work exists, shouldn't happen */
227 log_error(ls, "dlm_callback_work %x no work", lkb->lkb_id);
228 dlm_print_lkb(lkb);
229 dlm_dump_lkb_callbacks(lkb);
David Teiglande7fd4172006-01-18 09:30:29 +0000230 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500231
232 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
233 rv = dlm_rem_lkb_callback(ls, lkb, &callbacks[i], &resid);
234 if (rv < 0)
235 break;
236 }
237
238 if (resid) {
239 /* cbs remain, loop should have removed all, shouldn't happen */
240 log_error(ls, "dlm_callback_work %x resid %d", lkb->lkb_id,
241 resid);
242 dlm_print_lkb(lkb);
243 dlm_dump_lkb_callbacks(lkb);
244 }
245 mutex_unlock(&lkb->lkb_cb_mutex);
246
247 castfn = lkb->lkb_astfn;
248 bastfn = lkb->lkb_bastfn;
249
250 for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
251 if (!callbacks[i].seq)
252 break;
253 if (callbacks[i].flags & DLM_CB_SKIP) {
254 continue;
255 } else if (callbacks[i].flags & DLM_CB_BAST) {
256 bastfn(lkb->lkb_astparam, callbacks[i].mode);
257 } else if (callbacks[i].flags & DLM_CB_CAST) {
258 lkb->lkb_lksb->sb_status = callbacks[i].sb_status;
259 lkb->lkb_lksb->sb_flags = callbacks[i].sb_flags;
260 castfn(lkb->lkb_astparam);
261 }
262 }
263
264 /* undo kref_get from dlm_add_callback, may cause lkb to be freed */
265 dlm_put_lkb(lkb);
David Teiglande7fd4172006-01-18 09:30:29 +0000266}
267
David Teigland23e8e1a2011-04-05 13:16:24 -0500268int dlm_callback_start(struct dlm_ls *ls)
David Teiglande7fd4172006-01-18 09:30:29 +0000269{
David Teigland23e8e1a2011-04-05 13:16:24 -0500270 ls->ls_callback_wq = alloc_workqueue("dlm_callback",
Tejun Heoededf302013-07-30 08:40:24 -0400271 WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
David Teigland23e8e1a2011-04-05 13:16:24 -0500272 if (!ls->ls_callback_wq) {
273 log_print("can't start dlm_callback workqueue");
274 return -ENOMEM;
David Teiglande7fd4172006-01-18 09:30:29 +0000275 }
276 return 0;
277}
278
David Teigland23e8e1a2011-04-05 13:16:24 -0500279void dlm_callback_stop(struct dlm_ls *ls)
David Teiglande7fd4172006-01-18 09:30:29 +0000280{
David Teigland23e8e1a2011-04-05 13:16:24 -0500281 if (ls->ls_callback_wq)
282 destroy_workqueue(ls->ls_callback_wq);
283}
284
285void dlm_callback_suspend(struct dlm_ls *ls)
286{
287 set_bit(LSFL_CB_DELAY, &ls->ls_flags);
288
289 if (ls->ls_callback_wq)
290 flush_workqueue(ls->ls_callback_wq);
291}
292
293void dlm_callback_resume(struct dlm_ls *ls)
294{
295 struct dlm_lkb *lkb, *safe;
296 int count = 0;
297
298 clear_bit(LSFL_CB_DELAY, &ls->ls_flags);
299
300 if (!ls->ls_callback_wq)
301 return;
302
303 mutex_lock(&ls->ls_cb_mutex);
304 list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
305 list_del_init(&lkb->lkb_cb_list);
306 queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
307 count++;
David Teiglande7fd4172006-01-18 09:30:29 +0000308 }
David Teigland23e8e1a2011-04-05 13:16:24 -0500309 mutex_unlock(&ls->ls_cb_mutex);
David Teiglande7fd4172006-01-18 09:30:29 +0000310
David Teigland48756472012-04-26 15:54:29 -0500311 if (count)
David Teigland075f0172014-02-14 11:54:44 -0600312 log_rinfo(ls, "dlm_callback_resume %d", count);
David Teiglande7fd4172006-01-18 09:30:29 +0000313}
314