xref: /openbmc/linux/net/mpls/internal.h (revision 4e1a33b1)
1 #ifndef MPLS_INTERNAL_H
2 #define MPLS_INTERNAL_H
3 #include <net/mpls.h>
4 
5 struct mpls_entry_decoded {
6 	u32 label;
7 	u8 ttl;
8 	u8 tc;
9 	u8 bos;
10 };
11 
12 struct mpls_pcpu_stats {
13 	struct mpls_link_stats	stats;
14 	struct u64_stats_sync	syncp;
15 };
16 
17 struct mpls_dev {
18 	int				input_enabled;
19 	struct net_device		*dev;
20 	struct mpls_pcpu_stats __percpu	*stats;
21 
22 	struct ctl_table_header		*sysctl;
23 	struct rcu_head			rcu;
24 };
25 
26 #if BITS_PER_LONG == 32
27 
28 #define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field)		\
29 	do {								\
30 		__typeof__(*(mdev)->stats) *ptr =			\
31 			raw_cpu_ptr((mdev)->stats);			\
32 		local_bh_disable();					\
33 		u64_stats_update_begin(&ptr->syncp);			\
34 		ptr->stats.pkts_field++;				\
35 		ptr->stats.bytes_field += (len);			\
36 		u64_stats_update_end(&ptr->syncp);			\
37 		local_bh_enable();					\
38 	} while (0)
39 
40 #define MPLS_INC_STATS(mdev, field)					\
41 	do {								\
42 		__typeof__(*(mdev)->stats) *ptr =			\
43 			raw_cpu_ptr((mdev)->stats);			\
44 		local_bh_disable();					\
45 		u64_stats_update_begin(&ptr->syncp);			\
46 		ptr->stats.field++;					\
47 		u64_stats_update_end(&ptr->syncp);			\
48 		local_bh_enable();					\
49 	} while (0)
50 
51 #else
52 
53 #define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field)		\
54 	do {								\
55 		this_cpu_inc((mdev)->stats->stats.pkts_field);		\
56 		this_cpu_add((mdev)->stats->stats.bytes_field, (len));	\
57 	} while (0)
58 
59 #define MPLS_INC_STATS(mdev, field)			\
60 	this_cpu_inc((mdev)->stats->stats.field)
61 
62 #endif
63 
64 struct sk_buff;
65 
66 #define LABEL_NOT_SPECIFIED (1 << 20)
67 #define MAX_NEW_LABELS 2
68 
69 /* This maximum ha length copied from the definition of struct neighbour */
70 #define VIA_ALEN_ALIGN sizeof(unsigned long)
71 #define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN))
72 
73 enum mpls_payload_type {
74 	MPT_UNSPEC, /* IPv4 or IPv6 */
75 	MPT_IPV4 = 4,
76 	MPT_IPV6 = 6,
77 
78 	/* Other types not implemented:
79 	 *  - Pseudo-wire with or without control word (RFC4385)
80 	 *  - GAL (RFC5586)
81 	 */
82 };
83 
84 struct mpls_nh { /* next hop label forwarding entry */
85 	struct net_device __rcu *nh_dev;
86 	unsigned int		nh_flags;
87 	u32			nh_label[MAX_NEW_LABELS];
88 	u8			nh_labels;
89 	u8			nh_via_alen;
90 	u8			nh_via_table;
91 };
92 
93 /* The route, nexthops and vias are stored together in the same memory
94  * block:
95  *
96  * +----------------------+
97  * | mpls_route           |
98  * +----------------------+
99  * | mpls_nh 0            |
100  * +----------------------+
101  * | ...                  |
102  * +----------------------+
103  * | mpls_nh n-1          |
104  * +----------------------+
105  * | alignment padding    |
106  * +----------------------+
107  * | via[rt_max_alen] 0   |
108  * +----------------------+
109  * | ...                  |
110  * +----------------------+
111  * | via[rt_max_alen] n-1 |
112  * +----------------------+
113  */
114 struct mpls_route { /* next hop label forwarding entry */
115 	struct rcu_head		rt_rcu;
116 	u8			rt_protocol;
117 	u8			rt_payload_type;
118 	u8			rt_max_alen;
119 	unsigned int		rt_nhn;
120 	unsigned int		rt_nhn_alive;
121 	struct mpls_nh		rt_nh[0];
122 };
123 
124 #define for_nexthops(rt) {						\
125 	int nhsel; struct mpls_nh *nh;			\
126 	for (nhsel = 0, nh = (rt)->rt_nh;				\
127 	     nhsel < (rt)->rt_nhn;					\
128 	     nh++, nhsel++)
129 
130 #define change_nexthops(rt) {						\
131 	int nhsel; struct mpls_nh *nh;				\
132 	for (nhsel = 0,	nh = (struct mpls_nh *)((rt)->rt_nh);	\
133 	     nhsel < (rt)->rt_nhn;					\
134 	     nh++, nhsel++)
135 
136 #define endfor_nexthops(rt) }
137 
138 static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
139 {
140 	struct mpls_shim_hdr result;
141 	result.label_stack_entry =
142 		cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
143 			    (tc << MPLS_LS_TC_SHIFT) |
144 			    (bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
145 			    (ttl << MPLS_LS_TTL_SHIFT));
146 	return result;
147 }
148 
149 static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
150 {
151 	struct mpls_entry_decoded result;
152 	unsigned entry = be32_to_cpu(hdr->label_stack_entry);
153 
154 	result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
155 	result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
156 	result.tc =  (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
157 	result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
158 
159 	return result;
160 }
161 
162 static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev)
163 {
164 	return rcu_dereference_rtnl(dev->mpls_ptr);
165 }
166 
167 int nla_put_labels(struct sk_buff *skb, int attrtype,  u8 labels,
168 		   const u32 label[]);
169 int nla_get_labels(const struct nlattr *nla, u32 max_labels, u8 *labels,
170 		   u32 label[]);
171 int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table,
172 		u8 via[]);
173 bool mpls_output_possible(const struct net_device *dev);
174 unsigned int mpls_dev_mtu(const struct net_device *dev);
175 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu);
176 void mpls_stats_inc_outucastpkts(struct net_device *dev,
177 				 const struct sk_buff *skb);
178 
179 #endif /* MPLS_INTERNAL_H */
180