xref: /openbmc/linux/fs/ocfs2/cluster/tcp_internal.h (revision a1e58bbd)
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  * With version 11, we separate out the filesystem locking portion.  The
42  * filesystem now has a major.minor version it negotiates.  Version 11
43  * introduces this negotiation to the o2dlm protocol, and as such the
44  * version here in tcp_internal.h should not need to be bumped for
45  * filesystem locking changes.
46  *
47  * New in version 11
48  * 	- Negotiation of filesystem locking in the dlm join.
49  *
50  * New in version 10:
51  * 	- Meta/data locks combined
52  *
53  * New in version 9:
54  * 	- All votes removed
55  *
56  * New in version 8:
57  * 	- Replace delete inode votes with a cluster lock
58  *
59  * New in version 7:
60  * 	- DLM join domain includes the live nodemap
61  *
62  * New in version 6:
63  * 	- DLM lockres remote refcount fixes.
64  *
65  * New in version 5:
66  * 	- Network timeout checking protocol
67  *
68  * New in version 4:
69  * 	- Remove i_generation from lock names for better stat performance.
70  *
71  * New in version 3:
72  * 	- Replace dentry votes with a cluster lock
73  *
74  * New in version 2:
75  * 	- full 64 bit i_size in the metadata lock lvbs
76  * 	- introduction of "rw" lock and pushing meta/data locking down
77  */
78 #define O2NET_PROTOCOL_VERSION 11ULL
79 struct o2net_handshake {
80 	__be64	protocol_version;
81 	__be64	connector_id;
82 	__be32  o2hb_heartbeat_timeout_ms;
83 	__be32  o2net_idle_timeout_ms;
84 	__be32  o2net_keepalive_delay_ms;
85 	__be32  o2net_reconnect_delay_ms;
86 };
87 
88 struct o2net_node {
89 	/* this is never called from int/bh */
90 	spinlock_t			nn_lock;
91 
92 	/* set the moment an sc is allocated and a connect is started */
93 	struct o2net_sock_container	*nn_sc;
94 	/* _valid is only set after the handshake passes and tx can happen */
95 	unsigned			nn_sc_valid:1;
96 	/* if this is set tx just returns it */
97 	int				nn_persistent_error;
98 
99 	/* threads waiting for an sc to arrive wait on the wq for generation
100 	 * to increase.  it is increased when a connecting socket succeeds
101 	 * or fails or when an accepted socket is attached. */
102 	wait_queue_head_t		nn_sc_wq;
103 
104 	struct idr			nn_status_idr;
105 	struct list_head		nn_status_list;
106 
107 	/* connects are attempted from when heartbeat comes up until either hb
108 	 * goes down, the node is unconfigured, no connect attempts succeed
109 	 * before O2NET_CONN_IDLE_DELAY, or a connect succeeds.  connect_work
110 	 * is queued from set_nn_state both from hb up and from itself if a
111 	 * connect attempt fails and so can be self-arming.  shutdown is
112 	 * careful to first mark the nn such that no connects will be attempted
113 	 * before canceling delayed connect work and flushing the queue. */
114 	struct delayed_work		nn_connect_work;
115 	unsigned long			nn_last_connect_attempt;
116 
117 	/* this is queued as nodes come up and is canceled when a connection is
118 	 * established.  this expiring gives up on the node and errors out
119 	 * transmits */
120 	struct delayed_work		nn_connect_expired;
121 
122 	/* after we give up on a socket we wait a while before deciding
123 	 * that it is still heartbeating and that we should do some
124 	 * quorum work */
125 	struct delayed_work		nn_still_up;
126 };
127 
128 struct o2net_sock_container {
129 	struct kref		sc_kref;
130 	/* the next two are vaild for the life time of the sc */
131 	struct socket		*sc_sock;
132 	struct o2nm_node	*sc_node;
133 
134 	/* all of these sc work structs hold refs on the sc while they are
135 	 * queued.  they should not be able to ref a freed sc.  the teardown
136 	 * race is with o2net_wq destruction in o2net_stop_listening() */
137 
138 	/* rx and connect work are generated from socket callbacks.  sc
139 	 * shutdown removes the callbacks and then flushes the work queue */
140 	struct work_struct	sc_rx_work;
141 	struct work_struct	sc_connect_work;
142 	/* shutdown work is triggered in two ways.  the simple way is
143 	 * for a code path calls ensure_shutdown which gets a lock, removes
144 	 * the sc from the nn, and queues the work.  in this case the
145 	 * work is single-shot.  the work is also queued from a sock
146 	 * callback, though, and in this case the work will find the sc
147 	 * still on the nn and will call ensure_shutdown itself.. this
148 	 * ends up triggering the shutdown work again, though nothing
149 	 * will be done in that second iteration.  so work queue teardown
150 	 * has to be careful to remove the sc from the nn before waiting
151 	 * on the work queue so that the shutdown work doesn't remove the
152 	 * sc and rearm itself.
153 	 */
154 	struct work_struct	sc_shutdown_work;
155 
156 	struct timer_list	sc_idle_timeout;
157 	struct delayed_work	sc_keepalive_work;
158 
159 	unsigned		sc_handshake_ok:1;
160 
161 	struct page 		*sc_page;
162 	size_t			sc_page_off;
163 
164 	/* original handlers for the sockets */
165 	void			(*sc_state_change)(struct sock *sk);
166 	void			(*sc_data_ready)(struct sock *sk, int bytes);
167 
168 	struct timeval 		sc_tv_timer;
169 	struct timeval 		sc_tv_data_ready;
170 	struct timeval 		sc_tv_advance_start;
171 	struct timeval 		sc_tv_advance_stop;
172 	struct timeval 		sc_tv_func_start;
173 	struct timeval 		sc_tv_func_stop;
174 	u32			sc_msg_key;
175 	u16			sc_msg_type;
176 
177 	struct mutex		sc_send_lock;
178 };
179 
180 struct o2net_msg_handler {
181 	struct rb_node		nh_node;
182 	u32			nh_max_len;
183 	u32			nh_msg_type;
184 	u32			nh_key;
185 	o2net_msg_handler_func	*nh_func;
186 	o2net_msg_handler_func	*nh_func_data;
187 	o2net_post_msg_handler_func
188 				*nh_post_func;
189 	struct kref		nh_kref;
190 	struct list_head	nh_unregister_item;
191 };
192 
193 enum o2net_system_error {
194 	O2NET_ERR_NONE = 0,
195 	O2NET_ERR_NO_HNDLR,
196 	O2NET_ERR_OVERFLOW,
197 	O2NET_ERR_DIED,
198 	O2NET_ERR_MAX
199 };
200 
201 struct o2net_status_wait {
202 	enum o2net_system_error	ns_sys_status;
203 	s32			ns_status;
204 	int			ns_id;
205 	wait_queue_head_t	ns_wq;
206 	struct list_head	ns_node_item;
207 };
208 
209 #endif /* O2CLUSTER_TCP_INTERNAL_H */
210