2 * llc_core.c - Minimum needed routines for sap handling and module init/exit
4 * Copyright (c) 1997 by Procom Technology, Inc.
5 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
7 * This program can be redistributed or modified under the terms of the
8 * GNU General Public License as published by the Free Software Foundation.
9 * This program is distributed without any warranty or implied warranty
10 * of merchantability or fitness for a particular purpose.
12 * See the GNU General Public License for more details.
15 #include <linux/module.h>
16 #include <linux/interrupt.h>
17 #include <linux/if_ether.h>
18 #include <linux/netdevice.h>
19 #include <linux/slab.h>
20 #include <linux/string.h>
21 #include <linux/init.h>
22 #include <net/net_namespace.h>
25 LIST_HEAD(llc_sap_list
);
26 DEFINE_RWLOCK(llc_sap_list_lock
);
28 unsigned char llc_station_mac_sa
[ETH_ALEN
];
31 * llc_sap_alloc - allocates and initializes sap.
33 * Allocates and initializes sap.
35 static struct llc_sap
*llc_sap_alloc(void)
37 struct llc_sap
*sap
= kzalloc(sizeof(*sap
), GFP_ATOMIC
);
40 sap
->state
= LLC_SAP_STATE_ACTIVE
;
41 memcpy(sap
->laddr
.mac
, llc_station_mac_sa
, ETH_ALEN
);
42 rwlock_init(&sap
->sk_list
.lock
);
43 atomic_set(&sap
->refcnt
, 1);
49 * llc_add_sap - add sap to station list
50 * @sap: Address of the sap
52 * Adds a sap to the LLC's station sap list.
54 static void llc_add_sap(struct llc_sap
*sap
)
56 list_add_tail(&sap
->node
, &llc_sap_list
);
60 * llc_del_sap - del sap from station list
61 * @sap: Address of the sap
63 * Removes a sap to the LLC's station sap list.
65 static void llc_del_sap(struct llc_sap
*sap
)
67 write_lock_bh(&llc_sap_list_lock
);
69 write_unlock_bh(&llc_sap_list_lock
);
72 static struct llc_sap
*__llc_sap_find(unsigned char sap_value
)
76 list_for_each_entry(sap
, &llc_sap_list
, node
)
77 if (sap
->laddr
.lsap
== sap_value
)
85 * llc_sap_find - searchs a SAP in station
86 * @sap_value: sap to be found
88 * Searchs for a sap in the sap list of the LLC's station upon the sap ID.
89 * If the sap is found it will be refcounted and the user will have to do
90 * a llc_sap_put after use.
91 * Returns the sap or %NULL if not found.
93 struct llc_sap
*llc_sap_find(unsigned char sap_value
)
97 read_lock_bh(&llc_sap_list_lock
);
98 sap
= __llc_sap_find(sap_value
);
101 read_unlock_bh(&llc_sap_list_lock
);
106 * llc_sap_open - open interface to the upper layers.
108 * @func: rcv func for datalink protos
110 * Interface function to upper layer. Each one who wants to get a SAP
111 * (for example NetBEUI) should call this function. Returns the opened
112 * SAP for success, NULL for failure.
114 struct llc_sap
*llc_sap_open(unsigned char lsap
,
115 int (*func
)(struct sk_buff
*skb
,
116 struct net_device
*dev
,
117 struct packet_type
*pt
,
118 struct net_device
*orig_dev
))
120 struct llc_sap
*sap
= NULL
;
122 write_lock_bh(&llc_sap_list_lock
);
123 if (__llc_sap_find(lsap
)) /* SAP already exists */
125 sap
= llc_sap_alloc();
128 sap
->laddr
.lsap
= lsap
;
129 sap
->rcv_func
= func
;
132 write_unlock_bh(&llc_sap_list_lock
);
137 * llc_sap_close - close interface for upper layers.
138 * @sap: SAP to be closed.
140 * Close interface function to upper layer. Each one who wants to
141 * close an open SAP (for example NetBEUI) should call this function.
142 * Removes this sap from the list of saps in the station and then
143 * frees the memory for this sap.
145 void llc_sap_close(struct llc_sap
*sap
)
147 WARN_ON(!hlist_empty(&sap
->sk_list
.list
));
152 static struct packet_type llc_packet_type
= {
153 .type
= __constant_htons(ETH_P_802_2
),
157 static struct packet_type llc_tr_packet_type
= {
158 .type
= __constant_htons(ETH_P_TR_802_2
),
162 static int __init
llc_init(void)
164 struct net_device
*dev
;
166 dev
= first_net_device(&init_net
);
168 dev
= next_net_device(dev
);
171 memcpy(llc_station_mac_sa
, dev
->dev_addr
, ETH_ALEN
);
173 memset(llc_station_mac_sa
, 0, ETH_ALEN
);
174 dev_add_pack(&llc_packet_type
);
175 dev_add_pack(&llc_tr_packet_type
);
179 static void __exit
llc_exit(void)
181 dev_remove_pack(&llc_packet_type
);
182 dev_remove_pack(&llc_tr_packet_type
);
185 module_init(llc_init
);
186 module_exit(llc_exit
);
188 EXPORT_SYMBOL(llc_station_mac_sa
);
189 EXPORT_SYMBOL(llc_sap_list
);
190 EXPORT_SYMBOL(llc_sap_list_lock
);
191 EXPORT_SYMBOL(llc_sap_find
);
192 EXPORT_SYMBOL(llc_sap_open
);
193 EXPORT_SYMBOL(llc_sap_close
);
195 MODULE_LICENSE("GPL");
196 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
197 MODULE_DESCRIPTION("LLC IEEE 802.2 core support");