xref: /linux/fs/dlm/requestqueue.c (revision 621cde16e49b3ecf7d59a8106a20aaebfb4a59a9)
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,const struct dlm_message * ms)33 void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid,
34 			  const struct dlm_message *ms)
35 {
36 	struct rq_entry *e;
37 	int length = le16_to_cpu(ms->m_header.h_length) -
38 		sizeof(struct dlm_message);
39 
40 	e = kmalloc(sizeof(struct rq_entry) + length, GFP_ATOMIC);
41 	if (!e) {
42 		log_print("dlm_add_requestqueue: out of memory len %d", length);
43 		return;
44 	}
45 
46 	e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF;
47 	e->nodeid = nodeid;
48 	memcpy(&e->request, ms, sizeof(*ms));
49 	memcpy(&e->request.m_extra, ms->m_extra, length);
50 
51 	list_add_tail(&e->list, &ls->ls_requestqueue);
52 }
53 
54 /*
55  * Called by dlm_recoverd to process normal messages saved while recovery was
56  * happening.  Normal locking has been enabled before this is called.  dlm_recv
57  * upon receiving a message, will wait for all saved messages to be drained
58  * here before processing the message it got.  If a new dlm_ls_stop() arrives
59  * while we're processing these saved messages, it may block trying to suspend
60  * dlm_recv if dlm_recv is waiting for us in dlm_wait_requestqueue.  In that
61  * case, we don't abort since locking_stopped is still 0.  If dlm_recv is not
62  * waiting for us, then this processing may be aborted due to locking_stopped.
63  */
64 
dlm_process_requestqueue(struct dlm_ls * ls)65 int dlm_process_requestqueue(struct dlm_ls *ls)
66 {
67 	struct rq_entry *e;
68 	struct dlm_message *ms;
69 	int error = 0;
70 
71 	write_lock_bh(&ls->ls_requestqueue_lock);
72 	for (;;) {
73 		if (list_empty(&ls->ls_requestqueue)) {
74 			clear_bit(LSFL_RECV_MSG_BLOCKED, &ls->ls_flags);
75 			error = 0;
76 			break;
77 		}
78 		e = list_first_entry(&ls->ls_requestqueue, struct rq_entry, list);
79 
80 		ms = &e->request;
81 
82 		log_limit(ls, "dlm_process_requestqueue msg %d from %d "
83 			  "lkid %x remid %x result %d seq %u",
84 			  le32_to_cpu(ms->m_type),
85 			  le32_to_cpu(ms->m_header.h_nodeid),
86 			  le32_to_cpu(ms->m_lkid), le32_to_cpu(ms->m_remid),
87 			  from_dlm_errno(le32_to_cpu(ms->m_result)),
88 			  e->recover_seq);
89 
90 		dlm_receive_message_saved(ls, &e->request, e->recover_seq);
91 		list_del(&e->list);
92 		kfree(e);
93 
94 		if (dlm_locking_stopped(ls)) {
95 			log_debug(ls, "process_requestqueue abort running");
96 			error = -EINTR;
97 			break;
98 		}
99 		write_unlock_bh(&ls->ls_requestqueue_lock);
100 		schedule();
101 		write_lock_bh(&ls->ls_requestqueue_lock);
102 	}
103 	write_unlock_bh(&ls->ls_requestqueue_lock);
104 
105 	return error;
106 }
107 
purge_request(struct dlm_ls * ls,struct dlm_message * ms,int nodeid)108 static int purge_request(struct dlm_ls *ls, struct dlm_message *ms, int nodeid)
109 {
110 	__le32 type = ms->m_type;
111 
112 	/* the ls is being cleaned up and freed by release_lockspace */
113 	if (!atomic_read(&ls->ls_count))
114 		return 1;
115 
116 	if (dlm_is_removed(ls, nodeid))
117 		return 1;
118 
119 	/* directory operations are always purged because the directory is
120 	   always rebuilt during recovery and the lookups resent */
121 
122 	if (type == cpu_to_le32(DLM_MSG_REMOVE) ||
123 	    type == cpu_to_le32(DLM_MSG_LOOKUP) ||
124 	    type == cpu_to_le32(DLM_MSG_LOOKUP_REPLY))
125 		return 1;
126 
127 	if (!dlm_no_directory(ls))
128 		return 0;
129 
130 	return 1;
131 }
132 
dlm_purge_requestqueue(struct dlm_ls * ls)133 void dlm_purge_requestqueue(struct dlm_ls *ls)
134 {
135 	struct dlm_message *ms;
136 	struct rq_entry *e, *safe;
137 
138 	write_lock_bh(&ls->ls_requestqueue_lock);
139 	list_for_each_entry_safe(e, safe, &ls->ls_requestqueue, list) {
140 		ms =  &e->request;
141 
142 		if (purge_request(ls, ms, e->nodeid)) {
143 			list_del(&e->list);
144 			kfree(e);
145 		}
146 	}
147 	write_unlock_bh(&ls->ls_requestqueue_lock);
148 }
149 
150