xref: /openbmc/linux/net/hsr/hsr_main.c (revision 9123e3a7)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2011-2014 Autronica Fire and Security AS
3  *
4  * Author(s):
5  *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
6  *
7  * Event handling for HSR and PRP devices.
8  */
9 
10 #include <linux/netdevice.h>
11 #include <net/rtnetlink.h>
12 #include <linux/rculist.h>
13 #include <linux/timer.h>
14 #include <linux/etherdevice.h>
15 #include "hsr_main.h"
16 #include "hsr_device.h"
17 #include "hsr_netlink.h"
18 #include "hsr_framereg.h"
19 #include "hsr_slave.h"
20 
21 static bool hsr_slave_empty(struct hsr_priv *hsr)
22 {
23 	struct hsr_port *port;
24 
25 	hsr_for_each_port(hsr, port)
26 		if (port->type != HSR_PT_MASTER)
27 			return false;
28 	return true;
29 }
30 
31 static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
32 			     void *ptr)
33 {
34 	struct hsr_port *port, *master;
35 	struct net_device *dev;
36 	struct hsr_priv *hsr;
37 	LIST_HEAD(list_kill);
38 	int mtu_max;
39 	int res;
40 
41 	dev = netdev_notifier_info_to_dev(ptr);
42 	port = hsr_port_get_rtnl(dev);
43 	if (!port) {
44 		if (!is_hsr_master(dev))
45 			return NOTIFY_DONE;	/* Not an HSR device */
46 		hsr = netdev_priv(dev);
47 		port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
48 		if (!port) {
49 			/* Resend of notification concerning removed device? */
50 			return NOTIFY_DONE;
51 		}
52 	} else {
53 		hsr = port->hsr;
54 	}
55 
56 	switch (event) {
57 	case NETDEV_UP:		/* Administrative state DOWN */
58 	case NETDEV_DOWN:	/* Administrative state UP */
59 	case NETDEV_CHANGE:	/* Link (carrier) state changes */
60 		hsr_check_carrier_and_operstate(hsr);
61 		break;
62 	case NETDEV_CHANGENAME:
63 		if (is_hsr_master(dev))
64 			hsr_debugfs_rename(dev);
65 		break;
66 	case NETDEV_CHANGEADDR:
67 		if (port->type == HSR_PT_MASTER) {
68 			/* This should not happen since there's no
69 			 * ndo_set_mac_address() for HSR devices - i.e. not
70 			 * supported.
71 			 */
72 			break;
73 		}
74 
75 		master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
76 
77 		if (port->type == HSR_PT_SLAVE_A) {
78 			ether_addr_copy(master->dev->dev_addr, dev->dev_addr);
79 			call_netdevice_notifiers(NETDEV_CHANGEADDR,
80 						 master->dev);
81 		}
82 
83 		/* Make sure we recognize frames from ourselves in hsr_rcv() */
84 		port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
85 		res = hsr_create_self_node(hsr,
86 					   master->dev->dev_addr,
87 					   port ?
88 						port->dev->dev_addr :
89 						master->dev->dev_addr);
90 		if (res)
91 			netdev_warn(master->dev,
92 				    "Could not update HSR node address.\n");
93 		break;
94 	case NETDEV_CHANGEMTU:
95 		if (port->type == HSR_PT_MASTER)
96 			break; /* Handled in ndo_change_mtu() */
97 		mtu_max = hsr_get_max_mtu(port->hsr);
98 		master = hsr_port_get_hsr(port->hsr, HSR_PT_MASTER);
99 		master->dev->mtu = mtu_max;
100 		break;
101 	case NETDEV_UNREGISTER:
102 		if (!is_hsr_master(dev)) {
103 			master = hsr_port_get_hsr(port->hsr, HSR_PT_MASTER);
104 			hsr_del_port(port);
105 			if (hsr_slave_empty(master->hsr)) {
106 				const struct rtnl_link_ops *ops;
107 
108 				ops = master->dev->rtnl_link_ops;
109 				ops->dellink(master->dev, &list_kill);
110 				unregister_netdevice_many(&list_kill);
111 			}
112 		}
113 		break;
114 	case NETDEV_PRE_TYPE_CHANGE:
115 		/* HSR works only on Ethernet devices. Refuse slave to change
116 		 * its type.
117 		 */
118 		return NOTIFY_BAD;
119 	}
120 
121 	return NOTIFY_DONE;
122 }
123 
124 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt)
125 {
126 	struct hsr_port *port;
127 
128 	hsr_for_each_port(hsr, port)
129 		if (port->type == pt)
130 			return port;
131 	return NULL;
132 }
133 
134 static struct notifier_block hsr_nb = {
135 	.notifier_call = hsr_netdev_notify,	/* Slave event notifications */
136 };
137 
138 static int __init hsr_init(void)
139 {
140 	int res;
141 
142 	BUILD_BUG_ON(sizeof(struct hsr_tag) != HSR_HLEN);
143 
144 	register_netdevice_notifier(&hsr_nb);
145 	res = hsr_netlink_init();
146 
147 	return res;
148 }
149 
150 static void __exit hsr_exit(void)
151 {
152 	hsr_netlink_exit();
153 	hsr_debugfs_remove_root();
154 	unregister_netdevice_notifier(&hsr_nb);
155 }
156 
157 module_init(hsr_init);
158 module_exit(hsr_exit);
159 MODULE_LICENSE("GPL");
160