1/*
2 * drivers/net/team/team_mode_activebackup.c - Active-backup mode for team
3 * Copyright (c) 2011 Jiri Pirko <jpirko@redhat.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11#include <linux/kernel.h>
12#include <linux/types.h>
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/errno.h>
16#include <linux/netdevice.h>
17#include <net/rtnetlink.h>
18#include <linux/if_team.h>
19
20struct ab_priv {
21	struct team_port __rcu *active_port;
22	struct team_option_inst_info *ap_opt_inst_info;
23};
24
25static struct ab_priv *ab_priv(struct team *team)
26{
27	return (struct ab_priv *) &team->mode_priv;
28}
29
30static rx_handler_result_t ab_receive(struct team *team, struct team_port *port,
31				      struct sk_buff *skb) {
32	struct team_port *active_port;
33
34	active_port = rcu_dereference(ab_priv(team)->active_port);
35	if (active_port != port)
36		return RX_HANDLER_EXACT;
37	return RX_HANDLER_ANOTHER;
38}
39
40static bool ab_transmit(struct team *team, struct sk_buff *skb)
41{
42	struct team_port *active_port;
43
44	active_port = rcu_dereference_bh(ab_priv(team)->active_port);
45	if (unlikely(!active_port))
46		goto drop;
47	if (team_dev_queue_xmit(team, active_port, skb))
48		return false;
49	return true;
50
51drop:
52	dev_kfree_skb_any(skb);
53	return false;
54}
55
56static void ab_port_leave(struct team *team, struct team_port *port)
57{
58	if (ab_priv(team)->active_port == port) {
59		RCU_INIT_POINTER(ab_priv(team)->active_port, NULL);
60		team_option_inst_set_change(ab_priv(team)->ap_opt_inst_info);
61	}
62}
63
64static int ab_active_port_init(struct team *team,
65			       struct team_option_inst_info *info)
66{
67	ab_priv(team)->ap_opt_inst_info = info;
68	return 0;
69}
70
71static int ab_active_port_get(struct team *team, struct team_gsetter_ctx *ctx)
72{
73	struct team_port *active_port;
74
75	active_port = rcu_dereference_protected(ab_priv(team)->active_port,
76						lockdep_is_held(&team->lock));
77	if (active_port)
78		ctx->data.u32_val = active_port->dev->ifindex;
79	else
80		ctx->data.u32_val = 0;
81	return 0;
82}
83
84static int ab_active_port_set(struct team *team, struct team_gsetter_ctx *ctx)
85{
86	struct team_port *port;
87
88	list_for_each_entry(port, &team->port_list, list) {
89		if (port->dev->ifindex == ctx->data.u32_val) {
90			rcu_assign_pointer(ab_priv(team)->active_port, port);
91			return 0;
92		}
93	}
94	return -ENOENT;
95}
96
97static const struct team_option ab_options[] = {
98	{
99		.name = "activeport",
100		.type = TEAM_OPTION_TYPE_U32,
101		.init = ab_active_port_init,
102		.getter = ab_active_port_get,
103		.setter = ab_active_port_set,
104	},
105};
106
107static int ab_init(struct team *team)
108{
109	return team_options_register(team, ab_options, ARRAY_SIZE(ab_options));
110}
111
112static void ab_exit(struct team *team)
113{
114	team_options_unregister(team, ab_options, ARRAY_SIZE(ab_options));
115}
116
117static const struct team_mode_ops ab_mode_ops = {
118	.init			= ab_init,
119	.exit			= ab_exit,
120	.receive		= ab_receive,
121	.transmit		= ab_transmit,
122	.port_leave		= ab_port_leave,
123};
124
125static const struct team_mode ab_mode = {
126	.kind		= "activebackup",
127	.owner		= THIS_MODULE,
128	.priv_size	= sizeof(struct ab_priv),
129	.ops		= &ab_mode_ops,
130};
131
132static int __init ab_init_module(void)
133{
134	return team_mode_register(&ab_mode);
135}
136
137static void __exit ab_cleanup_module(void)
138{
139	team_mode_unregister(&ab_mode);
140}
141
142module_init(ab_init_module);
143module_exit(ab_cleanup_module);
144
145MODULE_LICENSE("GPL v2");
146MODULE_AUTHOR("Jiri Pirko <jpirko@redhat.com>");
147MODULE_DESCRIPTION("Active-backup mode for team");
148MODULE_ALIAS("team-mode-activebackup");
149