xref: /openbmc/linux/fs/ocfs2/cluster/tcp_internal.h (revision 64c70b1c)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * Copyright (C) 2005 Oracle.  All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public
17  * License along with this program; if not, write to the
18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19  * Boston, MA 021110-1307, USA.
20  */
21 
22 #ifndef O2CLUSTER_TCP_INTERNAL_H
23 #define O2CLUSTER_TCP_INTERNAL_H
24 
25 #define O2NET_MSG_MAGIC           ((u16)0xfa55)
26 #define O2NET_MSG_STATUS_MAGIC    ((u16)0xfa56)
27 #define O2NET_MSG_KEEP_REQ_MAGIC  ((u16)0xfa57)
28 #define O2NET_MSG_KEEP_RESP_MAGIC ((u16)0xfa58)
29 
30 /* we're delaying our quorum decision so that heartbeat will have timed
31  * out truly dead nodes by the time we come around to making decisions
32  * on their number */
33 #define O2NET_QUORUM_DELAY_MS	((o2hb_dead_threshold + 2) * O2HB_REGION_TIMEOUT_MS)
34 
35 /*
36  * This version number represents quite a lot, unfortunately.  It not
37  * only represents the raw network message protocol on the wire but also
38  * locking semantics of the file system using the protocol.  It should
39  * be somewhere else, I'm sure, but right now it isn't.
40  *
41  * New in version 8:
42  * 	- Replace delete inode votes with a cluster lock
43  *
44  * New in version 7:
45  * 	- DLM join domain includes the live nodemap
46  *
47  * New in version 6:
48  * 	- DLM lockres remote refcount fixes.
49  *
50  * New in version 5:
51  * 	- Network timeout checking protocol
52  *
53  * New in version 4:
54  * 	- Remove i_generation from lock names for better stat performance.
55  *
56  * New in version 3:
57  * 	- Replace dentry votes with a cluster lock
58  *
59  * New in version 2:
60  * 	- full 64 bit i_size in the metadata lock lvbs
61  * 	- introduction of "rw" lock and pushing meta/data locking down
62  */
63 #define O2NET_PROTOCOL_VERSION 8ULL
64 struct o2net_handshake {
65 	__be64	protocol_version;
66 	__be64	connector_id;
67 	__be32  o2hb_heartbeat_timeout_ms;
68 	__be32  o2net_idle_timeout_ms;
69 	__be32  o2net_keepalive_delay_ms;
70 	__be32  o2net_reconnect_delay_ms;
71 };
72 
73 struct o2net_node {
74 	/* this is never called from int/bh */
75 	spinlock_t			nn_lock;
76 
77 	/* set the moment an sc is allocated and a connect is started */
78 	struct o2net_sock_container	*nn_sc;
79 	/* _valid is only set after the handshake passes and tx can happen */
80 	unsigned			nn_sc_valid:1;
81 	/* if this is set tx just returns it */
82 	int				nn_persistent_error;
83 
84 	/* threads waiting for an sc to arrive wait on the wq for generation
85 	 * to increase.  it is increased when a connecting socket succeeds
86 	 * or fails or when an accepted socket is attached. */
87 	wait_queue_head_t		nn_sc_wq;
88 
89 	struct idr			nn_status_idr;
90 	struct list_head		nn_status_list;
91 
92 	/* connects are attempted from when heartbeat comes up until either hb
93 	 * goes down, the node is unconfigured, no connect attempts succeed
94 	 * before O2NET_CONN_IDLE_DELAY, or a connect succeeds.  connect_work
95 	 * is queued from set_nn_state both from hb up and from itself if a
96 	 * connect attempt fails and so can be self-arming.  shutdown is
97 	 * careful to first mark the nn such that no connects will be attempted
98 	 * before canceling delayed connect work and flushing the queue. */
99 	struct delayed_work		nn_connect_work;
100 	unsigned long			nn_last_connect_attempt;
101 
102 	/* this is queued as nodes come up and is canceled when a connection is
103 	 * established.  this expiring gives up on the node and errors out
104 	 * transmits */
105 	struct delayed_work		nn_connect_expired;
106 
107 	/* after we give up on a socket we wait a while before deciding
108 	 * that it is still heartbeating and that we should do some
109 	 * quorum work */
110 	struct delayed_work		nn_still_up;
111 };
112 
113 struct o2net_sock_container {
114 	struct kref		sc_kref;
115 	/* the next two are vaild for the life time of the sc */
116 	struct socket		*sc_sock;
117 	struct o2nm_node	*sc_node;
118 
119 	/* all of these sc work structs hold refs on the sc while they are
120 	 * queued.  they should not be able to ref a freed sc.  the teardown
121 	 * race is with o2net_wq destruction in o2net_stop_listening() */
122 
123 	/* rx and connect work are generated from socket callbacks.  sc
124 	 * shutdown removes the callbacks and then flushes the work queue */
125 	struct work_struct	sc_rx_work;
126 	struct work_struct	sc_connect_work;
127 	/* shutdown work is triggered in two ways.  the simple way is
128 	 * for a code path calls ensure_shutdown which gets a lock, removes
129 	 * the sc from the nn, and queues the work.  in this case the
130 	 * work is single-shot.  the work is also queued from a sock
131 	 * callback, though, and in this case the work will find the sc
132 	 * still on the nn and will call ensure_shutdown itself.. this
133 	 * ends up triggering the shutdown work again, though nothing
134 	 * will be done in that second iteration.  so work queue teardown
135 	 * has to be careful to remove the sc from the nn before waiting
136 	 * on the work queue so that the shutdown work doesn't remove the
137 	 * sc and rearm itself.
138 	 */
139 	struct work_struct	sc_shutdown_work;
140 
141 	struct timer_list	sc_idle_timeout;
142 	struct delayed_work	sc_keepalive_work;
143 
144 	unsigned		sc_handshake_ok:1;
145 
146 	struct page 		*sc_page;
147 	size_t			sc_page_off;
148 
149 	/* original handlers for the sockets */
150 	void			(*sc_state_change)(struct sock *sk);
151 	void			(*sc_data_ready)(struct sock *sk, int bytes);
152 
153 	struct timeval 		sc_tv_timer;
154 	struct timeval 		sc_tv_data_ready;
155 	struct timeval 		sc_tv_advance_start;
156 	struct timeval 		sc_tv_advance_stop;
157 	struct timeval 		sc_tv_func_start;
158 	struct timeval 		sc_tv_func_stop;
159 	u32			sc_msg_key;
160 	u16			sc_msg_type;
161 
162 	struct mutex		sc_send_lock;
163 };
164 
165 struct o2net_msg_handler {
166 	struct rb_node		nh_node;
167 	u32			nh_max_len;
168 	u32			nh_msg_type;
169 	u32			nh_key;
170 	o2net_msg_handler_func	*nh_func;
171 	o2net_msg_handler_func	*nh_func_data;
172 	o2net_post_msg_handler_func
173 				*nh_post_func;
174 	struct kref		nh_kref;
175 	struct list_head	nh_unregister_item;
176 };
177 
178 enum o2net_system_error {
179 	O2NET_ERR_NONE = 0,
180 	O2NET_ERR_NO_HNDLR,
181 	O2NET_ERR_OVERFLOW,
182 	O2NET_ERR_DIED,
183 	O2NET_ERR_MAX
184 };
185 
186 struct o2net_status_wait {
187 	enum o2net_system_error	ns_sys_status;
188 	s32			ns_status;
189 	int			ns_id;
190 	wait_queue_head_t	ns_wq;
191 	struct list_head	ns_node_item;
192 };
193 
194 #endif /* O2CLUSTER_TCP_INTERNAL_H */
195