1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers/net/team/team_mode_activebackup.c - Active-backup mode for team
4  * Copyright (c) 2011 Jiri Pirko <jpirko@redhat.com>
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/netdevice.h>
13 #include <net/rtnetlink.h>
14 #include <linux/if_team.h>
15 
16 struct ab_priv {
17 	struct team_port __rcu *active_port;
18 	struct team_option_inst_info *ap_opt_inst_info;
19 };
20 
21 static struct ab_priv *ab_priv(struct team *team)
22 {
23 	return (struct ab_priv *) &team->mode_priv;
24 }
25 
26 static rx_handler_result_t ab_receive(struct team *team, struct team_port *port,
27 				      struct sk_buff *skb) {
28 	struct team_port *active_port;
29 
30 	active_port = rcu_dereference(ab_priv(team)->active_port);
31 	if (active_port != port)
32 		return RX_HANDLER_EXACT;
33 	return RX_HANDLER_ANOTHER;
34 }
35 
36 static bool ab_transmit(struct team *team, struct sk_buff *skb)
37 {
38 	struct team_port *active_port;
39 
40 	active_port = rcu_dereference_bh(ab_priv(team)->active_port);
41 	if (unlikely(!active_port))
42 		goto drop;
43 	if (team_dev_queue_xmit(team, active_port, skb))
44 		return false;
45 	return true;
46 
47 drop:
48 	dev_kfree_skb_any(skb);
49 	return false;
50 }
51 
52 static void ab_port_leave(struct team *team, struct team_port *port)
53 {
54 	if (ab_priv(team)->active_port == port) {
55 		RCU_INIT_POINTER(ab_priv(team)->active_port, NULL);
56 		team_option_inst_set_change(ab_priv(team)->ap_opt_inst_info);
57 	}
58 }
59 
60 static void ab_active_port_init(struct team *team,
61 				struct team_option_inst_info *info)
62 {
63 	ab_priv(team)->ap_opt_inst_info = info;
64 }
65 
66 static void ab_active_port_get(struct team *team, struct team_gsetter_ctx *ctx)
67 {
68 	struct team_port *active_port;
69 
70 	active_port = rcu_dereference_protected(ab_priv(team)->active_port,
71 						lockdep_is_held(&team->lock));
72 	if (active_port)
73 		ctx->data.u32_val = active_port->dev->ifindex;
74 	else
75 		ctx->data.u32_val = 0;
76 }
77 
78 static int ab_active_port_set(struct team *team, struct team_gsetter_ctx *ctx)
79 {
80 	struct team_port *port;
81 
82 	list_for_each_entry(port, &team->port_list, list) {
83 		if (port->dev->ifindex == ctx->data.u32_val) {
84 			rcu_assign_pointer(ab_priv(team)->active_port, port);
85 			return 0;
86 		}
87 	}
88 	return -ENOENT;
89 }
90 
91 static const struct team_option ab_options[] = {
92 	{
93 		.name = "activeport",
94 		.type = TEAM_OPTION_TYPE_U32,
95 		.init = ab_active_port_init,
96 		.getter = ab_active_port_get,
97 		.setter = ab_active_port_set,
98 	},
99 };
100 
101 static int ab_init(struct team *team)
102 {
103 	return team_options_register(team, ab_options, ARRAY_SIZE(ab_options));
104 }
105 
106 static void ab_exit(struct team *team)
107 {
108 	team_options_unregister(team, ab_options, ARRAY_SIZE(ab_options));
109 }
110 
111 static const struct team_mode_ops ab_mode_ops = {
112 	.init			= ab_init,
113 	.exit			= ab_exit,
114 	.receive		= ab_receive,
115 	.transmit		= ab_transmit,
116 	.port_leave		= ab_port_leave,
117 };
118 
119 static const struct team_mode ab_mode = {
120 	.kind		= "activebackup",
121 	.owner		= THIS_MODULE,
122 	.priv_size	= sizeof(struct ab_priv),
123 	.ops		= &ab_mode_ops,
124 	.lag_tx_type	= NETDEV_LAG_TX_TYPE_ACTIVEBACKUP,
125 };
126 
127 static int __init ab_init_module(void)
128 {
129 	return team_mode_register(&ab_mode);
130 }
131 
132 static void __exit ab_cleanup_module(void)
133 {
134 	team_mode_unregister(&ab_mode);
135 }
136 
137 module_init(ab_init_module);
138 module_exit(ab_cleanup_module);
139 
140 MODULE_LICENSE("GPL v2");
141 MODULE_AUTHOR("Jiri Pirko <jpirko@redhat.com>");
142 MODULE_DESCRIPTION("Active-backup mode for team");
143 MODULE_ALIAS_TEAM_MODE("activebackup");
144