xref: /linux/drivers/net/team/team_mode_activebackup.c (revision a508da6cc0093171833efb8376b00473f24221b9)
1 /*
2  * net/drivers/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 
20 struct ab_priv {
21 	struct team_port __rcu *active_port;
22 };
23 
24 static struct ab_priv *ab_priv(struct team *team)
25 {
26 	return (struct ab_priv *) &team->mode_priv;
27 }
28 
29 static rx_handler_result_t ab_receive(struct team *team, struct team_port *port,
30 				      struct sk_buff *skb) {
31 	struct team_port *active_port;
32 
33 	active_port = rcu_dereference(ab_priv(team)->active_port);
34 	if (active_port != port)
35 		return RX_HANDLER_EXACT;
36 	return RX_HANDLER_ANOTHER;
37 }
38 
39 static bool ab_transmit(struct team *team, struct sk_buff *skb)
40 {
41 	struct team_port *active_port;
42 
43 	active_port = rcu_dereference(ab_priv(team)->active_port);
44 	if (unlikely(!active_port))
45 		goto drop;
46 	skb->dev = active_port->dev;
47 	if (dev_queue_xmit(skb))
48 		return false;
49 	return true;
50 
51 drop:
52 	dev_kfree_skb_any(skb);
53 	return false;
54 }
55 
56 static 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 }
61 
62 static int ab_active_port_get(struct team *team, struct team_gsetter_ctx *ctx)
63 {
64 	if (ab_priv(team)->active_port)
65 		ctx->data.u32_val = ab_priv(team)->active_port->dev->ifindex;
66 	else
67 		ctx->data.u32_val = 0;
68 	return 0;
69 }
70 
71 static int ab_active_port_set(struct team *team, struct team_gsetter_ctx *ctx)
72 {
73 	struct team_port *port;
74 
75 	list_for_each_entry(port, &team->port_list, list) {
76 		if (port->dev->ifindex == ctx->data.u32_val) {
77 			rcu_assign_pointer(ab_priv(team)->active_port, port);
78 			return 0;
79 		}
80 	}
81 	return -ENOENT;
82 }
83 
84 static const struct team_option ab_options[] = {
85 	{
86 		.name = "activeport",
87 		.type = TEAM_OPTION_TYPE_U32,
88 		.getter = ab_active_port_get,
89 		.setter = ab_active_port_set,
90 	},
91 };
92 
93 static int ab_init(struct team *team)
94 {
95 	return team_options_register(team, ab_options, ARRAY_SIZE(ab_options));
96 }
97 
98 static void ab_exit(struct team *team)
99 {
100 	team_options_unregister(team, ab_options, ARRAY_SIZE(ab_options));
101 }
102 
103 static const struct team_mode_ops ab_mode_ops = {
104 	.init			= ab_init,
105 	.exit			= ab_exit,
106 	.receive		= ab_receive,
107 	.transmit		= ab_transmit,
108 	.port_leave		= ab_port_leave,
109 };
110 
111 static struct team_mode ab_mode = {
112 	.kind		= "activebackup",
113 	.owner		= THIS_MODULE,
114 	.priv_size	= sizeof(struct ab_priv),
115 	.ops		= &ab_mode_ops,
116 };
117 
118 static int __init ab_init_module(void)
119 {
120 	return team_mode_register(&ab_mode);
121 }
122 
123 static void __exit ab_cleanup_module(void)
124 {
125 	team_mode_unregister(&ab_mode);
126 }
127 
128 module_init(ab_init_module);
129 module_exit(ab_cleanup_module);
130 
131 MODULE_LICENSE("GPL v2");
132 MODULE_AUTHOR("Jiri Pirko <jpirko@redhat.com>");
133 MODULE_DESCRIPTION("Active-backup mode for team");
134 MODULE_ALIAS("team-mode-activebackup");
135