net/netlink/af_netlink.h

   1 #ifndef _AF_NETLINK_H
   2 #define _AF_NETLINK_H
   3
   4 #include <linux/rhashtable.h>
   5 #include <linux/atomic.h>
   6 #include <net/sock.h>
   7
   8 #define NLGRPSZ(x)      (ALIGN(x, sizeof(unsigned long) * 8) / 8)
   9 #define NLGRPLONGS(x)   (NLGRPSZ(x)/sizeof(unsigned long))
  10
  11 struct netlink_ring {
  12         void                    **pg_vec;
  13         unsigned int            head;
  14         unsigned int            frames_per_block;
  15         unsigned int            frame_size;
  16         unsigned int            frame_max;
  17
  18         unsigned int            pg_vec_order;
  19         unsigned int            pg_vec_pages;
  20         unsigned int            pg_vec_len;
  21
  22         atomic_t                pending;
  23 };
  24
  25 struct netlink_sock {
  26         /* struct sock has to be the first member of netlink_sock */
  27         struct sock             sk;
  28         u32                     portid;
  29         u32                     dst_portid;
  30         u32                     dst_group;
  31         u32                     flags;
  32         u32                     subscriptions;
  33         u32                     ngroups;
  34         unsigned long           *groups;
  35         unsigned long           state;
  36         size_t                  max_recvmsg_len;
  37         wait_queue_head_t       wait;
  38         bool                    bound;
  39         bool                    cb_running;
  40         struct netlink_callback cb;
  41         struct mutex            *cb_mutex;
  42         struct mutex            cb_def_mutex;
  43         void                    (*netlink_rcv)(struct sk_buff *skb);
  44         int                     (*netlink_bind)(struct net *net, int group);
  45         void                    (*netlink_unbind)(struct net *net, int group);
  46         struct module           *module;
  47 #ifdef CONFIG_NETLINK_MMAP
  48         struct mutex            pg_vec_lock;
  49         struct netlink_ring     rx_ring;
  50         struct netlink_ring     tx_ring;
  51         atomic_t                mapped;
  52 #endif /* CONFIG_NETLINK_MMAP */
  53
  54         struct rhash_head       node;
  55         struct rcu_head         rcu;
  56 };
  57
  58 static inline struct netlink_sock *nlk_sk(struct sock *sk)
  59 {
  60         return container_of(sk, struct netlink_sock, sk);
  61 }
  62
  63 static inline bool netlink_skb_is_mmaped(const struct sk_buff *skb)
  64 {
  65 #ifdef CONFIG_NETLINK_MMAP
  66         return NETLINK_CB(skb).flags & NETLINK_SKB_MMAPED;
  67 #else
  68         return false;
  69 #endif /* CONFIG_NETLINK_MMAP */
  70 }
  71
  72 struct netlink_table {
  73         struct rhashtable       hash;
  74         struct hlist_head       mc_list;
  75         struct listeners __rcu  *listeners;
  76         unsigned int            flags;
  77         unsigned int            groups;
  78         struct mutex            *cb_mutex;
  79         struct module           *module;
  80         int                     (*bind)(struct net *net, int group);
  81         void                    (*unbind)(struct net *net, int group);
  82         bool                    (*compare)(struct net *net, struct sock *sock);
  83         int                     registered;
  84 };
  85
  86 extern struct netlink_table *nl_table;
  87 extern rwlock_t nl_table_lock;
  88
  89 #endif