1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Lan Emulation client header file
4  *
5  * Marko Kiiskila <mkiiskila@yahoo.com>
6  */
7 
8 #ifndef _LEC_H_
9 #define _LEC_H_
10 
11 #include <linux/atmdev.h>
12 #include <linux/netdevice.h>
13 #include <linux/atmlec.h>
14 
15 #define LEC_HEADER_LEN 16
16 
17 struct lecdatahdr_8023 {
18 	__be16 le_header;
19 	unsigned char h_dest[ETH_ALEN];
20 	unsigned char h_source[ETH_ALEN];
21 	__be16 h_type;
22 };
23 
24 struct lecdatahdr_8025 {
25 	__be16 le_header;
26 	unsigned char ac_pad;
27 	unsigned char fc;
28 	unsigned char h_dest[ETH_ALEN];
29 	unsigned char h_source[ETH_ALEN];
30 };
31 
32 #define LEC_MINIMUM_8023_SIZE   62
33 #define LEC_MINIMUM_8025_SIZE   16
34 
35 /*
36  * Operations that LANE2 capable device can do. Two first functions
37  * are used to make the device do things. See spec 3.1.3 and 3.1.4.
38  *
39  * The third function is intended for the MPOA component sitting on
40  * top of the LANE device. The MPOA component assigns it's own function
41  * to (*associate_indicator)() and the LANE device will use that
42  * function to tell about TLVs it sees floating through.
43  *
44  */
45 struct lane2_ops {
46 	int (*resolve) (struct net_device *dev, const u8 *dst_mac, int force,
47 			u8 **tlvs, u32 *sizeoftlvs);
48 	int (*associate_req) (struct net_device *dev, const u8 *lan_dst,
49 			      const u8 *tlvs, u32 sizeoftlvs);
50 	void (*associate_indicator) (struct net_device *dev, const u8 *mac_addr,
51 				     const u8 *tlvs, u32 sizeoftlvs);
52 };
53 
54 /*
55  * ATM LAN Emulation supports both LLC & Dix Ethernet EtherType
56  * frames.
57  *
58  * 1. Dix Ethernet EtherType frames encoded by placing EtherType
59  *    field in h_type field. Data follows immediately after header.
60  * 2. LLC Data frames whose total length, including LLC field and data,
61  *    but not padding required to meet the minimum data frame length,
62  *    is less than ETH_P_802_3_MIN MUST be encoded by placing that length
63  *    in the h_type field. The LLC field follows header immediately.
64  * 3. LLC data frames longer than this maximum MUST be encoded by placing
65  *    the value 0 in the h_type field.
66  *
67  */
68 
69 /* Hash table size */
70 #define LEC_ARP_TABLE_SIZE 16
71 
72 struct lec_priv {
73 	unsigned short lecid;			/* Lecid of this client */
74 	struct hlist_head lec_arp_empty_ones;
75 						/* Used for storing VCC's that don't have a MAC address attached yet */
76 	struct hlist_head lec_arp_tables[LEC_ARP_TABLE_SIZE];
77 						/* Actual LE ARP table */
78 	struct hlist_head lec_no_forward;
79 						/*
80 						 * Used for storing VCC's (and forward packets from) which are to
81 						 * age out by not using them to forward packets.
82 						 * This is because to some LE clients there will be 2 VCCs. Only
83 						 * one of them gets used.
84 						 */
85 	struct hlist_head mcast_fwds;
86 						/*
87 						 * With LANEv2 it is possible that BUS (or a special multicast server)
88 						 * establishes multiple Multicast Forward VCCs to us. This list
89 						 * collects all those VCCs. LANEv1 client has only one item in this
90 						 * list. These entries are not aged out.
91 						 */
92 	spinlock_t lec_arp_lock;
93 	struct atm_vcc *mcast_vcc;		/* Default Multicast Send VCC */
94 	struct atm_vcc *lecd;
95 	struct delayed_work lec_arp_work;	/* C10 */
96 	unsigned int maximum_unknown_frame_count;
97 						/*
98 						 * Within the period of time defined by this variable, the client will send
99 						 * no more than C10 frames to BUS for a given unicast destination. (C11)
100 						 */
101 	unsigned long max_unknown_frame_time;
102 						/*
103 						 * If no traffic has been sent in this vcc for this period of time,
104 						 * vcc will be torn down (C12)
105 						 */
106 	unsigned long vcc_timeout_period;
107 						/*
108 						 * An LE Client MUST not retry an LE_ARP_REQUEST for a
109 						 * given frame's LAN Destination more than maximum retry count times,
110 						 * after the first LEC_ARP_REQUEST (C13)
111 						 */
112 	unsigned short max_retry_count;
113 						/*
114 						 * Max time the client will maintain an entry in its arp cache in
115 						 * absence of a verification of that relationship (C17)
116 						 */
117 	unsigned long aging_time;
118 						/*
119 						 * Max time the client will maintain an entry in cache when
120 						 * topology change flag is true (C18)
121 						 */
122 	unsigned long forward_delay_time;	/* Topology change flag (C19) */
123 	int topology_change;
124 						/*
125 						 * Max time the client expects an LE_ARP_REQUEST/LE_ARP_RESPONSE
126 						 * cycle to take (C20)
127 						 */
128 	unsigned long arp_response_time;
129 						/*
130 						 * Time limit ot wait to receive an LE_FLUSH_RESPONSE after the
131 						 * LE_FLUSH_REQUEST has been sent before taking recover action. (C21)
132 						 */
133 	unsigned long flush_timeout;
134 						/* The time since sending a frame to the bus after which the
135 						 * LE Client may assume that the frame has been either discarded or
136 						 * delivered to the recipient (C22)
137 						 */
138 	unsigned long path_switching_delay;
139 
140 	u8 *tlvs;				/* LANE2: TLVs are new */
141 	u32 sizeoftlvs;				/* The size of the tlv array in bytes */
142 	int lane_version;			/* LANE2 */
143 	int itfnum;				/* e.g. 2 for lec2, 5 for lec5 */
144 	struct lane2_ops *lane2_ops;		/* can be NULL for LANE v1 */
145 	int is_proxy;				/* bridge between ATM and Ethernet */
146 };
147 
148 struct lec_vcc_priv {
149 	void (*old_pop) (struct atm_vcc *vcc, struct sk_buff *skb);
150 	int xoff;
151 };
152 
153 #define LEC_VCC_PRIV(vcc)	((struct lec_vcc_priv *)((vcc)->user_back))
154 
155 #endif				/* _LEC_H_ */
156