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