1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *******************************************************************************
4 **
5 ** Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
6 **
7 **
8 *******************************************************************************
9 ******************************************************************************/
10
11 #include "dlm_internal.h"
12 #include "member.h"
13 #include "lock.h"
14 #include "dir.h"
15 #include "config.h"
16 #include "requestqueue.h"
17 #include "util.h"
18
19 struct rq_entry {
20 struct list_head list;
21 uint32_t recover_seq;
22 int nodeid;
23 struct dlm_message request;
24 };
25
26 /*
27 * Requests received while the lockspace is in recovery get added to the
28 * request queue and processed when recovery is complete. This happens when
29 * the lockspace is suspended on some nodes before it is on others, or the
30 * lockspace is enabled on some while still suspended on others.
31 */
32
dlm_add_requestqueue(struct dlm_ls * ls,int nodeid,struct dlm_message * ms)33 void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_message *ms)
34 {
35 struct rq_entry *e;
36 int length = le16_to_cpu(ms->m_header.h_length) -
37 sizeof(struct dlm_message);
38
39 e = kmalloc(sizeof(struct rq_entry) + length, GFP_NOFS);
40 if (!e) {
41 log_print("dlm_add_requestqueue: out of memory len %d", length);
42 return;
43 }
44
45 e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF;
46 e->nodeid = nodeid;
47 memcpy(&e->request, ms, le16_to_cpu(ms->m_header.h_length));
48
49 atomic_inc(&ls->ls_requestqueue_cnt);
50 mutex_lock(&ls->ls_requestqueue_mutex);
51 list_add_tail(&e->list, &ls->ls_requestqueue);
52 mutex_unlock(&ls->ls_requestqueue_mutex);
53 }
54
55 /*
56 * Called by dlm_recoverd to process normal messages saved while recovery was
57 * happening. Normal locking has been enabled before this is called. dlm_recv
58 * upon receiving a message, will wait for all saved messages to be drained
59 * here before processing the message it got. If a new dlm_ls_stop() arrives
60 * while we're processing these saved messages, it may block trying to suspend
61 * dlm_recv if dlm_recv is waiting for us in dlm_wait_requestqueue. In that
62 * case, we don't abort since locking_stopped is still 0. If dlm_recv is not
63 * waiting for us, then this processing may be aborted due to locking_stopped.
64 */
65
dlm_process_requestqueue(struct dlm_ls * ls)66 int dlm_process_requestqueue(struct dlm_ls *ls)
67 {
68 struct rq_entry *e;
69 struct dlm_message *ms;
70 int error = 0;
71
72 mutex_lock(&ls->ls_requestqueue_mutex);
73
74 for (;;) {
75 if (list_empty(&ls->ls_requestqueue)) {
76 mutex_unlock(&ls->ls_requestqueue_mutex);
77 error = 0;
78 break;
79 }
80 e = list_entry(ls->ls_requestqueue.next, struct rq_entry, list);
81 mutex_unlock(&ls->ls_requestqueue_mutex);
82
83 ms = &e->request;
84
85 log_limit(ls, "dlm_process_requestqueue msg %d from %d "
86 "lkid %x remid %x result %d seq %u",
87 le32_to_cpu(ms->m_type),
88 le32_to_cpu(ms->m_header.h_nodeid),
89 le32_to_cpu(ms->m_lkid), le32_to_cpu(ms->m_remid),
90 from_dlm_errno(le32_to_cpu(ms->m_result)),
91 e->recover_seq);
92
93 dlm_receive_message_saved(ls, &e->request, e->recover_seq);
94
95 mutex_lock(&ls->ls_requestqueue_mutex);
96 list_del(&e->list);
97 if (atomic_dec_and_test(&ls->ls_requestqueue_cnt))
98 wake_up(&ls->ls_requestqueue_wait);
99 kfree(e);
100
101 if (dlm_locking_stopped(ls)) {
102 log_debug(ls, "process_requestqueue abort running");
103 mutex_unlock(&ls->ls_requestqueue_mutex);
104 error = -EINTR;
105 break;
106 }
107 schedule();
108 }
109
110 return error;
111 }
112
113 /*
114 * After recovery is done, locking is resumed and dlm_recoverd takes all the
115 * saved requests and processes them as they would have been by dlm_recv. At
116 * the same time, dlm_recv will start receiving new requests from remote nodes.
117 * We want to delay dlm_recv processing new requests until dlm_recoverd has
118 * finished processing the old saved requests. We don't check for locking
119 * stopped here because dlm_ls_stop won't stop locking until it's suspended us
120 * (dlm_recv).
121 */
122
dlm_wait_requestqueue(struct dlm_ls * ls)123 void dlm_wait_requestqueue(struct dlm_ls *ls)
124 {
125 wait_event(ls->ls_requestqueue_wait,
126 atomic_read(&ls->ls_requestqueue_cnt) == 0);
127 }
128
purge_request(struct dlm_ls * ls,struct dlm_message * ms,int nodeid)129 static int purge_request(struct dlm_ls *ls, struct dlm_message *ms, int nodeid)
130 {
131 __le32 type = ms->m_type;
132
133 /* the ls is being cleaned up and freed by release_lockspace */
134 if (!atomic_read(&ls->ls_count))
135 return 1;
136
137 if (dlm_is_removed(ls, nodeid))
138 return 1;
139
140 /* directory operations are always purged because the directory is
141 always rebuilt during recovery and the lookups resent */
142
143 if (type == cpu_to_le32(DLM_MSG_REMOVE) ||
144 type == cpu_to_le32(DLM_MSG_LOOKUP) ||
145 type == cpu_to_le32(DLM_MSG_LOOKUP_REPLY))
146 return 1;
147
148 if (!dlm_no_directory(ls))
149 return 0;
150
151 return 1;
152 }
153
dlm_purge_requestqueue(struct dlm_ls * ls)154 void dlm_purge_requestqueue(struct dlm_ls *ls)
155 {
156 struct dlm_message *ms;
157 struct rq_entry *e, *safe;
158
159 mutex_lock(&ls->ls_requestqueue_mutex);
160 list_for_each_entry_safe(e, safe, &ls->ls_requestqueue, list) {
161 ms = &e->request;
162
163 if (purge_request(ls, ms, e->nodeid)) {
164 list_del(&e->list);
165 if (atomic_dec_and_test(&ls->ls_requestqueue_cnt))
166 wake_up(&ls->ls_requestqueue_wait);
167 kfree(e);
168 }
169 }
170 mutex_unlock(&ls->ls_requestqueue_mutex);
171 }
172
173