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
  25 struct net_device;
  26 struct packet_type;
  27 struct sk_buff;
  28
  29 struct 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  */
  54 struct 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
  71 static inline
  72 struct 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
  77 static inline
  78 u32 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
  84 static inline
  85 struct 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
  95 extern struct list_head llc_sap_list;
  96 extern spinlock_t llc_sap_list_lock;
  97
  98 extern int llc_rcv(struct sk_buff *skb, struct net_device *dev,
  99                    struct packet_type *pt, struct net_device *orig_dev);
 100
 101 extern int llc_mac_hdr_init(struct sk_buff *skb,
 102                             const unsigned char *sa, const unsigned char *da);
 103
 104 extern void llc_add_pack(int type, void (*handler)(struct llc_sap *sap,
 105                                                    struct sk_buff *skb));
 106 extern void llc_remove_pack(int type);
 107
 108 extern void llc_set_station_handler(void (*handler)(struct sk_buff *skb));
 109
 110 extern 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));
 115 static inline void llc_sap_hold(struct llc_sap *sap)
 116 {
 117         atomic_inc(&sap->refcnt);
 118 }
 119
 120 extern void llc_sap_close(struct llc_sap *sap);
 121
 122 static 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
 128 extern struct llc_sap *llc_sap_find(unsigned char sap_value);
 129
 130 extern int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
 131                                      unsigned char *dmac, unsigned char dsap);
 132
 133 extern void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
 134 extern void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);
 135
 136 extern void llc_station_init(void);
 137 extern void llc_station_exit(void);
 138
 139 #ifdef CONFIG_PROC_FS
 140 extern int llc_proc_init(void);
 141 extern 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
 147 extern int llc_sysctl_init(void);
 148 extern void llc_sysctl_exit(void);
 149
 150 extern int sysctl_llc2_ack_timeout;
 151 extern int sysctl_llc2_busy_timeout;
 152 extern int sysctl_llc2_p_timeout;
 153 extern 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 */