LXR linux/include/net/llc.h

   1#ifndef LLC_H
   2#define LLC_H
   3/*
   4 * Copyright (c) 1997 by Procom Technology, Inc.
   5 *               2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   6 *
   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.
  11 *
  12 * See the GNU General Public License for more details.
  13 */
  14
  15#include <linux/if.h>
  16#include <linux/if_ether.h>
  17#include <linux/list.h>
  18#include <linux/spinlock.h>
  19#include <linux/rculist_nulls.h>
  20#include <linux/hash.h>
  21#include <linux/jhash.h>
  22
  23#include <linux/atomic.h>
  24
  25struct net_device;
  26struct packet_type;
  27struct sk_buff;
  28
  29struct llc_addr {
  30        unsigned char lsap;
  31        unsigned char mac[IFHWADDRLEN];
  32};
  33
  34#define LLC_SAP_STATE_INACTIVE  1
  35#define LLC_SAP_STATE_ACTIVE    2
  36
  37#define LLC_SK_DEV_HASH_BITS 6
  38#define LLC_SK_DEV_HASH_ENTRIES (1<<LLC_SK_DEV_HASH_BITS)
  39
  40#define LLC_SK_LADDR_HASH_BITS 6
  41#define LLC_SK_LADDR_HASH_ENTRIES (1<<LLC_SK_LADDR_HASH_BITS)
  42
  43/**
  44 * struct llc_sap - Defines the SAP component
  45 *
  46 * @station - station this sap belongs to
  47 * @state - sap state
  48 * @p_bit - only lowest-order bit used
  49 * @f_bit - only lowest-order bit used
  50 * @laddr - SAP value in this 'lsap'
  51 * @node - entry in station sap_list
  52 * @sk_list - LLC sockets this one manages
  53 */
  54struct llc_sap {
  55        unsigned char    state;
  56        unsigned char    p_bit;
  57        unsigned char    f_bit;
  58        atomic_t         refcnt;
  59        int              (*rcv_func)(struct sk_buff *skb,
  60                                     struct net_device *dev,
  61                                     struct packet_type *pt,
  62                                     struct net_device *orig_dev);
  63        struct llc_addr  laddr;
  64        struct list_head node;
  65        spinlock_t sk_lock;
  66        int sk_count;
  67        struct hlist_nulls_head sk_laddr_hash[LLC_SK_LADDR_HASH_ENTRIES];
  68        struct hlist_head sk_dev_hash[LLC_SK_DEV_HASH_ENTRIES];
  69};
  70
  71static inline
  72struct hlist_head *llc_sk_dev_hash(struct llc_sap *sap, int ifindex)
  73{
  74        return &sap->sk_dev_hash[ifindex % LLC_SK_DEV_HASH_ENTRIES];
  75}
  76
  77static inline
  78u32 llc_sk_laddr_hashfn(struct llc_sap *sap, const struct llc_addr *laddr)
  79{
  80        return hash_32(jhash(laddr->mac, sizeof(laddr->mac), 0),
  81                       LLC_SK_LADDR_HASH_BITS);
  82}
  83
  84static inline
  85struct hlist_nulls_head *llc_sk_laddr_hash(struct llc_sap *sap,
  86                                           const struct llc_addr *laddr)
  87{
  88        return &sap->sk_laddr_hash[llc_sk_laddr_hashfn(sap, laddr)];
  89}
  90
  91#define LLC_DEST_INVALID         0      /* Invalid LLC PDU type */
  92#define LLC_DEST_SAP             1      /* Type 1 goes here */
  93#define LLC_DEST_CONN            2      /* Type 2 goes here */
  94
  95extern struct list_head llc_sap_list;
  96extern spinlock_t llc_sap_list_lock;
  97
  98extern int llc_rcv(struct sk_buff *skb, struct net_device *dev,
  99                   struct packet_type *pt, struct net_device *orig_dev);
 100
 101extern int llc_mac_hdr_init(struct sk_buff *skb,
 102                            const unsigned char *sa, const unsigned char *da);
 103
 104extern void llc_add_pack(int type, void (*handler)(struct llc_sap *sap,
 105                                                   struct sk_buff *skb));
 106extern void llc_remove_pack(int type);
 107
 108extern void llc_set_station_handler(void (*handler)(struct sk_buff *skb));
 109
 110extern struct llc_sap *llc_sap_open(unsigned char lsap,
 111                                    int (*rcv)(struct sk_buff *skb,
 112                                               struct net_device *dev,
 113                                               struct packet_type *pt,
 114                                               struct net_device *orig_dev));
 115static inline void llc_sap_hold(struct llc_sap *sap)
 116{
 117        atomic_inc(&sap->refcnt);
 118}
 119
 120extern void llc_sap_close(struct llc_sap *sap);
 121
 122static inline void llc_sap_put(struct llc_sap *sap)
 123{
 124        if (atomic_dec_and_test(&sap->refcnt))
 125                llc_sap_close(sap);
 126}
 127
 128extern struct llc_sap *llc_sap_find(unsigned char sap_value);
 129
 130extern int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
 131                                     unsigned char *dmac, unsigned char dsap);
 132
 133extern void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
 134extern void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);
 135
 136extern void llc_station_init(void);
 137extern void llc_station_exit(void);
 138
 139#ifdef CONFIG_PROC_FS
 140extern int llc_proc_init(void);
 141extern void llc_proc_exit(void);
 142#else
 143#define llc_proc_init() (0)
 144#define llc_proc_exit() do { } while(0)
 145#endif /* CONFIG_PROC_FS */
 146#ifdef CONFIG_SYSCTL
 147extern int llc_sysctl_init(void);
 148extern void llc_sysctl_exit(void);
 149
 150extern int sysctl_llc2_ack_timeout;
 151extern int sysctl_llc2_busy_timeout;
 152extern int sysctl_llc2_p_timeout;
 153extern int sysctl_llc2_rej_timeout;
 154#else
 155#define llc_sysctl_init() (0)
 156#define llc_sysctl_exit() do { } while(0)
 157#endif /* CONFIG_SYSCTL */
 158#endif /* LLC_H */
 159