xref: /linux/net/hsr/hsr_main.h (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 /* Copyright 2011-2014 Autronica Fire and Security AS
2  *
3  * This program is free software; you can redistribute it and/or modify it
4  * under the terms of the GNU General Public License as published by the Free
5  * Software Foundation; either version 2 of the License, or (at your option)
6  * any later version.
7  *
8  * Author(s):
9  *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
10  */
11 
12 #ifndef __HSR_PRIVATE_H
13 #define __HSR_PRIVATE_H
14 
15 #include <linux/netdevice.h>
16 #include <linux/list.h>
17 
18 
19 /* Time constants as specified in the HSR specification (IEC-62439-3 2010)
20  * Table 8.
21  * All values in milliseconds.
22  */
23 #define HSR_LIFE_CHECK_INTERVAL		 2000 /* ms */
24 #define HSR_NODE_FORGET_TIME		60000 /* ms */
25 #define HSR_ANNOUNCE_INTERVAL		  100 /* ms */
26 
27 
28 /* By how much may slave1 and slave2 timestamps of latest received frame from
29  * each node differ before we notify of communication problem?
30  */
31 #define MAX_SLAVE_DIFF			 3000 /* ms */
32 #define HSR_SEQNR_START			(USHRT_MAX - 1024)
33 #define HSR_SUP_SEQNR_START		(HSR_SEQNR_START / 2)
34 
35 
36 /* How often shall we check for broken ring and remove node entries older than
37  * HSR_NODE_FORGET_TIME?
38  */
39 #define PRUNE_PERIOD			 3000 /* ms */
40 
41 
42 #define HSR_TLV_ANNOUNCE		   22
43 #define HSR_TLV_LIFE_CHECK		   23
44 
45 
46 /* HSR Tag.
47  * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
48  * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
49  * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
50  * encapsulated protocol } instead.
51  *
52  * Field names as defined in the IEC:2010 standard for HSR.
53  */
54 struct hsr_tag {
55 	__be16		path_and_LSDU_size;
56 	__be16		sequence_nr;
57 	__be16		encap_proto;
58 } __packed;
59 
60 #define HSR_HLEN	6
61 
62 #define HSR_V1_SUP_LSDUSIZE		52
63 
64 /* The helper functions below assumes that 'path' occupies the 4 most
65  * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
66  * equivalently, the 4 most significant bits of HSR tag byte 14).
67  *
68  * This is unclear in the IEC specification; its definition of MAC addresses
69  * indicates the spec is written with the least significant bit first (to the
70  * left). This, however, would mean that the LSDU field would be split in two
71  * with the path field in-between, which seems strange. I'm guessing the MAC
72  * address definition is in error.
73  */
74 static inline u16 get_hsr_tag_path(struct hsr_tag *ht)
75 {
76 	return ntohs(ht->path_and_LSDU_size) >> 12;
77 }
78 
79 static inline u16 get_hsr_tag_LSDU_size(struct hsr_tag *ht)
80 {
81 	return ntohs(ht->path_and_LSDU_size) & 0x0FFF;
82 }
83 
84 static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
85 {
86 	ht->path_and_LSDU_size = htons(
87 			(ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
88 }
89 
90 static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
91 {
92 	ht->path_and_LSDU_size = htons(
93 			(ntohs(ht->path_and_LSDU_size) & 0xF000) |
94 			(LSDU_size & 0x0FFF));
95 }
96 
97 struct hsr_ethhdr {
98 	struct ethhdr	ethhdr;
99 	struct hsr_tag	hsr_tag;
100 } __packed;
101 
102 
103 /* HSR Supervision Frame data types.
104  * Field names as defined in the IEC:2010 standard for HSR.
105  */
106 struct hsr_sup_tag {
107 	__be16		path_and_HSR_Ver;
108 	__be16		sequence_nr;
109 	__u8		HSR_TLV_Type;
110 	__u8		HSR_TLV_Length;
111 } __packed;
112 
113 struct hsr_sup_payload {
114 	unsigned char	MacAddressA[ETH_ALEN];
115 } __packed;
116 
117 static inline u16 get_hsr_stag_path(struct hsr_sup_tag *hst)
118 {
119 	return get_hsr_tag_path((struct hsr_tag *) hst);
120 }
121 
122 static inline u16 get_hsr_stag_HSR_ver(struct hsr_sup_tag *hst)
123 {
124 	return get_hsr_tag_LSDU_size((struct hsr_tag *) hst);
125 }
126 
127 static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
128 {
129 	set_hsr_tag_path((struct hsr_tag *) hst, path);
130 }
131 
132 static inline void set_hsr_stag_HSR_Ver(struct hsr_sup_tag *hst, u16 HSR_Ver)
133 {
134 	set_hsr_tag_LSDU_size((struct hsr_tag *) hst, HSR_Ver);
135 }
136 
137 struct hsrv0_ethhdr_sp {
138 	struct ethhdr		ethhdr;
139 	struct hsr_sup_tag	hsr_sup;
140 } __packed;
141 
142 struct hsrv1_ethhdr_sp {
143 	struct ethhdr		ethhdr;
144 	struct hsr_tag		hsr;
145 	struct hsr_sup_tag	hsr_sup;
146 } __packed;
147 
148 
149 enum hsr_port_type {
150 	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
151 	HSR_PT_SLAVE_A,
152 	HSR_PT_SLAVE_B,
153 	HSR_PT_INTERLINK,
154 	HSR_PT_MASTER,
155 	HSR_PT_PORTS,	/* This must be the last item in the enum */
156 };
157 
158 struct hsr_port {
159 	struct list_head	port_list;
160 	struct net_device	*dev;
161 	struct hsr_priv		*hsr;
162 	enum hsr_port_type	type;
163 };
164 
165 struct hsr_priv {
166 	struct rcu_head		rcu_head;
167 	struct list_head	ports;
168 	struct list_head	node_db;	/* Known HSR nodes */
169 	struct list_head	self_node_db;	/* MACs of slaves */
170 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
171 	struct timer_list	prune_timer;
172 	int announce_count;
173 	u16 sequence_nr;
174 	u16 sup_sequence_nr;			/* For HSRv1 separate seq_nr for supervision */
175 	u8 protVersion;					/* Indicate if HSRv0 or HSRv1. */
176 	spinlock_t seqnr_lock;			/* locking for sequence_nr */
177 	unsigned char		sup_multicast_addr[ETH_ALEN];
178 };
179 
180 #define hsr_for_each_port(hsr, port) \
181 	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
182 
183 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
184 
185 /* Caller must ensure skb is a valid HSR frame */
186 static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
187 {
188 	struct hsr_ethhdr *hsr_ethhdr;
189 
190 	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
191 	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
192 }
193 
194 #endif /*  __HSR_PRIVATE_H */
195