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Diffstat (limited to 'net/llc/llc_core.c')
| -rw-r--r-- | net/llc/llc_core.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/net/llc/llc_core.c b/net/llc/llc_core.c new file mode 100644 index 00000000000..5ff02c080a0 --- /dev/null +++ b/net/llc/llc_core.c @@ -0,0 +1,179 @@ +/* + * llc_core.c - Minimum needed routines for sap handling and module init/exit + * + * Copyright (c) 1997 by Procom Technology, Inc. + * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * + * This program can be redistributed or modified under the terms of the + * GNU General Public License as published by the Free Software Foundation. + * This program is distributed without any warranty or implied warranty + * of merchantability or fitness for a particular purpose. + * + * See the GNU General Public License for more details. + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/if_ether.h> +#include <linux/netdevice.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/init.h> +#include <net/llc.h> + +LIST_HEAD(llc_sap_list); +DEFINE_RWLOCK(llc_sap_list_lock); + +unsigned char llc_station_mac_sa[ETH_ALEN]; + +/** + * llc_sap_alloc - allocates and initializes sap. + * + * Allocates and initializes sap. + */ +static struct llc_sap *llc_sap_alloc(void) +{ + struct llc_sap *sap = kmalloc(sizeof(*sap), GFP_ATOMIC); + + if (sap) { + memset(sap, 0, sizeof(*sap)); + sap->state = LLC_SAP_STATE_ACTIVE; + memcpy(sap->laddr.mac, llc_station_mac_sa, ETH_ALEN); + rwlock_init(&sap->sk_list.lock); + } + return sap; +} + +/** + * llc_add_sap - add sap to station list + * @sap: Address of the sap + * + * Adds a sap to the LLC's station sap list. + */ +static void llc_add_sap(struct llc_sap *sap) +{ + write_lock_bh(&llc_sap_list_lock); + list_add_tail(&sap->node, &llc_sap_list); + write_unlock_bh(&llc_sap_list_lock); +} + +/** + * llc_del_sap - del sap from station list + * @sap: Address of the sap + * + * Removes a sap to the LLC's station sap list. + */ +static void llc_del_sap(struct llc_sap *sap) +{ + write_lock_bh(&llc_sap_list_lock); + list_del(&sap->node); + write_unlock_bh(&llc_sap_list_lock); +} + +/** + * llc_sap_find - searchs a SAP in station + * @sap_value: sap to be found + * + * Searchs for a sap in the sap list of the LLC's station upon the sap ID. + * Returns the sap or %NULL if not found. + */ +struct llc_sap *llc_sap_find(unsigned char sap_value) +{ + struct llc_sap* sap; + + read_lock_bh(&llc_sap_list_lock); + list_for_each_entry(sap, &llc_sap_list, node) + if (sap->laddr.lsap == sap_value) + goto out; + sap = NULL; +out: + read_unlock_bh(&llc_sap_list_lock); + return sap; +} + +/** + * llc_sap_open - open interface to the upper layers. + * @lsap: SAP number. + * @func: rcv func for datalink protos + * + * Interface function to upper layer. Each one who wants to get a SAP + * (for example NetBEUI) should call this function. Returns the opened + * SAP for success, NULL for failure. + */ +struct llc_sap *llc_sap_open(unsigned char lsap, + int (*func)(struct sk_buff *skb, + struct net_device *dev, + struct packet_type *pt)) +{ + struct llc_sap *sap = llc_sap_find(lsap); + + if (sap) { /* SAP already exists */ + sap = NULL; + goto out; + } + sap = llc_sap_alloc(); + if (!sap) + goto out; + sap->laddr.lsap = lsap; + sap->rcv_func = func; + llc_add_sap(sap); +out: + return sap; +} + +/** + * llc_sap_close - close interface for upper layers. + * @sap: SAP to be closed. + * + * Close interface function to upper layer. Each one who wants to + * close an open SAP (for example NetBEUI) should call this function. + * Removes this sap from the list of saps in the station and then + * frees the memory for this sap. + */ +void llc_sap_close(struct llc_sap *sap) +{ + WARN_ON(!hlist_empty(&sap->sk_list.list)); + llc_del_sap(sap); + kfree(sap); +} + +static struct packet_type llc_packet_type = { + .type = __constant_htons(ETH_P_802_2), + .func = llc_rcv, +}; + +static struct packet_type llc_tr_packet_type = { + .type = __constant_htons(ETH_P_TR_802_2), + .func = llc_rcv, +}; + +static int __init llc_init(void) +{ + if (dev_base->next) + memcpy(llc_station_mac_sa, dev_base->next->dev_addr, ETH_ALEN); + else + memset(llc_station_mac_sa, 0, ETH_ALEN); + dev_add_pack(&llc_packet_type); + dev_add_pack(&llc_tr_packet_type); + return 0; +} + +static void __exit llc_exit(void) +{ + dev_remove_pack(&llc_packet_type); + dev_remove_pack(&llc_tr_packet_type); +} + +module_init(llc_init); +module_exit(llc_exit); + +EXPORT_SYMBOL(llc_station_mac_sa); +EXPORT_SYMBOL(llc_sap_list); +EXPORT_SYMBOL(llc_sap_list_lock); +EXPORT_SYMBOL(llc_sap_find); +EXPORT_SYMBOL(llc_sap_open); +EXPORT_SYMBOL(llc_sap_close); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); +MODULE_DESCRIPTION("LLC IEEE 802.2 core support"); |