xref: /openbmc/linux/fs/ocfs2/cluster/tcp_internal.h (revision 87c2ce3b)
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 /* same as hb delay, we're waiting for another node to recognize our hb */
31 #define O2NET_RECONNECT_DELAY_MS	O2HB_REGION_TIMEOUT_MS
32 
33 /* we're delaying our quorum decision so that heartbeat will have timed
34  * out truly dead nodes by the time we come around to making decisions
35  * on their number */
36 #define O2NET_QUORUM_DELAY_MS	((o2hb_dead_threshold + 2) * O2HB_REGION_TIMEOUT_MS)
37 
38 #define O2NET_KEEPALIVE_DELAY_SECS	5
39 #define O2NET_IDLE_TIMEOUT_SECS		10
40 
41 /*
42  * This version number represents quite a lot, unfortunately.  It not
43  * only represents the raw network message protocol on the wire but also
44  * locking semantics of the file system using the protocol.  It should
45  * be somewhere else, I'm sure, but right now it isn't.
46  *
47  * New in version 2:
48  * 	- full 64 bit i_size in the metadata lock lvbs
49  * 	- introduction of "rw" lock and pushing meta/data locking down
50  */
51 #define O2NET_PROTOCOL_VERSION 2ULL
52 struct o2net_handshake {
53 	__be64	protocol_version;
54 	__be64	connector_id;
55 };
56 
57 struct o2net_node {
58 	/* this is never called from int/bh */
59 	spinlock_t			nn_lock;
60 
61 	/* set the moment an sc is allocated and a connect is started */
62 	struct o2net_sock_container	*nn_sc;
63 	/* _valid is only set after the handshake passes and tx can happen */
64 	unsigned			nn_sc_valid:1;
65 	/* if this is set tx just returns it */
66 	int				nn_persistent_error;
67 
68 	/* threads waiting for an sc to arrive wait on the wq for generation
69 	 * to increase.  it is increased when a connecting socket succeeds
70 	 * or fails or when an accepted socket is attached. */
71 	wait_queue_head_t		nn_sc_wq;
72 
73 	struct idr			nn_status_idr;
74 	struct list_head		nn_status_list;
75 
76 	/* connects are attempted from when heartbeat comes up until either hb
77 	 * goes down, the node is unconfigured, no connect attempts succeed
78 	 * before O2NET_CONN_IDLE_DELAY, or a connect succeeds.  connect_work
79 	 * is queued from set_nn_state both from hb up and from itself if a
80 	 * connect attempt fails and so can be self-arming.  shutdown is
81 	 * careful to first mark the nn such that no connects will be attempted
82 	 * before canceling delayed connect work and flushing the queue. */
83 	struct work_struct		nn_connect_work;
84 	unsigned long			nn_last_connect_attempt;
85 
86 	/* this is queued as nodes come up and is canceled when a connection is
87 	 * established.  this expiring gives up on the node and errors out
88 	 * transmits */
89 	struct work_struct		nn_connect_expired;
90 
91 	/* after we give up on a socket we wait a while before deciding
92 	 * that it is still heartbeating and that we should do some
93 	 * quorum work */
94 	struct work_struct		nn_still_up;
95 };
96 
97 struct o2net_sock_container {
98 	struct kref		sc_kref;
99 	/* the next two are vaild for the life time of the sc */
100 	struct socket		*sc_sock;
101 	struct o2nm_node	*sc_node;
102 
103 	/* all of these sc work structs hold refs on the sc while they are
104 	 * queued.  they should not be able to ref a freed sc.  the teardown
105 	 * race is with o2net_wq destruction in o2net_stop_listening() */
106 
107 	/* rx and connect work are generated from socket callbacks.  sc
108 	 * shutdown removes the callbacks and then flushes the work queue */
109 	struct work_struct	sc_rx_work;
110 	struct work_struct	sc_connect_work;
111 	/* shutdown work is triggered in two ways.  the simple way is
112 	 * for a code path calls ensure_shutdown which gets a lock, removes
113 	 * the sc from the nn, and queues the work.  in this case the
114 	 * work is single-shot.  the work is also queued from a sock
115 	 * callback, though, and in this case the work will find the sc
116 	 * still on the nn and will call ensure_shutdown itself.. this
117 	 * ends up triggering the shutdown work again, though nothing
118 	 * will be done in that second iteration.  so work queue teardown
119 	 * has to be careful to remove the sc from the nn before waiting
120 	 * on the work queue so that the shutdown work doesn't remove the
121 	 * sc and rearm itself.
122 	 */
123 	struct work_struct	sc_shutdown_work;
124 
125 	struct timer_list	sc_idle_timeout;
126 	struct work_struct	sc_keepalive_work;
127 
128 	unsigned		sc_handshake_ok:1;
129 
130 	struct page 		*sc_page;
131 	size_t			sc_page_off;
132 
133 	/* original handlers for the sockets */
134 	void			(*sc_state_change)(struct sock *sk);
135 	void			(*sc_data_ready)(struct sock *sk, int bytes);
136 
137 	struct timeval 		sc_tv_timer;
138 	struct timeval 		sc_tv_data_ready;
139 	struct timeval 		sc_tv_advance_start;
140 	struct timeval 		sc_tv_advance_stop;
141 	struct timeval 		sc_tv_func_start;
142 	struct timeval 		sc_tv_func_stop;
143 	u32			sc_msg_key;
144 	u16			sc_msg_type;
145 };
146 
147 struct o2net_msg_handler {
148 	struct rb_node		nh_node;
149 	u32			nh_max_len;
150 	u32			nh_msg_type;
151 	u32			nh_key;
152 	o2net_msg_handler_func	*nh_func;
153 	o2net_msg_handler_func	*nh_func_data;
154 	struct kref		nh_kref;
155 	struct list_head	nh_unregister_item;
156 };
157 
158 enum o2net_system_error {
159 	O2NET_ERR_NONE = 0,
160 	O2NET_ERR_NO_HNDLR,
161 	O2NET_ERR_OVERFLOW,
162 	O2NET_ERR_DIED,
163 	O2NET_ERR_MAX
164 };
165 
166 struct o2net_status_wait {
167 	enum o2net_system_error	ns_sys_status;
168 	s32			ns_status;
169 	int			ns_id;
170 	wait_queue_head_t	ns_wq;
171 	struct list_head	ns_node_item;
172 };
173 
174 #endif /* O2CLUSTER_TCP_INTERNAL_H */
175