kernel-fxtec-pro1x/include/net/genetlink.h
Thomas Graf d387f6ad10 [NETLINK]: Add notification message sending interface
Adds nlmsg_notify() implementing proper notification logic. The
message is multicasted to all listeners in the group. The
applications the requests orignates from can request a unicast
back report in which case said socket will be excluded from the
multicast to avoid duplicated notifications.

nlmsg_multicast() is extended to take allocation flags to
allow notification in atomic contexts.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:54:49 -07:00

174 lines
4.5 KiB
C

#ifndef __NET_GENERIC_NETLINK_H
#define __NET_GENERIC_NETLINK_H
#include <linux/genetlink.h>
#include <net/netlink.h>
/**
* struct genl_family - generic netlink family
* @id: protocol family idenfitier
* @hdrsize: length of user specific header in bytes
* @name: name of family
* @version: protocol version
* @maxattr: maximum number of attributes supported
* @attrbuf: buffer to store parsed attributes
* @ops_list: list of all assigned operations
* @family_list: family list
*/
struct genl_family
{
unsigned int id;
unsigned int hdrsize;
char name[GENL_NAMSIZ];
unsigned int version;
unsigned int maxattr;
struct nlattr ** attrbuf; /* private */
struct list_head ops_list; /* private */
struct list_head family_list; /* private */
};
#define GENL_ADMIN_PERM 0x01
/**
* struct genl_info - receiving information
* @snd_seq: sending sequence number
* @snd_pid: netlink pid of sender
* @nlhdr: netlink message header
* @genlhdr: generic netlink message header
* @userhdr: user specific header
* @attrs: netlink attributes
*/
struct genl_info
{
u32 snd_seq;
u32 snd_pid;
struct nlmsghdr * nlhdr;
struct genlmsghdr * genlhdr;
void * userhdr;
struct nlattr ** attrs;
};
/**
* struct genl_ops - generic netlink operations
* @cmd: command identifier
* @flags: flags
* @policy: attribute validation policy
* @doit: standard command callback
* @dumpit: callback for dumpers
* @ops_list: operations list
*/
struct genl_ops
{
u8 cmd;
unsigned int flags;
struct nla_policy *policy;
int (*doit)(struct sk_buff *skb,
struct genl_info *info);
int (*dumpit)(struct sk_buff *skb,
struct netlink_callback *cb);
struct list_head ops_list;
};
extern int genl_register_family(struct genl_family *family);
extern int genl_unregister_family(struct genl_family *family);
extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
extern struct sock *genl_sock;
/**
* genlmsg_put - Add generic netlink header to netlink message
* @skb: socket buffer holding the message
* @pid: netlink pid the message is addressed to
* @seq: sequence number (usually the one of the sender)
* @type: netlink message type
* @hdrlen: length of the user specific header
* @flags netlink message flags
* @cmd: generic netlink command
* @version: version
*
* Returns pointer to user specific header
*/
static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
int type, int hdrlen, int flags,
u8 cmd, u8 version)
{
struct nlmsghdr *nlh;
struct genlmsghdr *hdr;
nlh = nlmsg_put(skb, pid, seq, type, GENL_HDRLEN + hdrlen, flags);
if (nlh == NULL)
return NULL;
hdr = nlmsg_data(nlh);
hdr->cmd = cmd;
hdr->version = version;
hdr->reserved = 0;
return (char *) hdr + GENL_HDRLEN;
}
/**
* genlmsg_end - Finalize a generic netlink message
* @skb: socket buffer the message is stored in
* @hdr: user specific header
*/
static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
{
return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
}
/**
* genlmsg_cancel - Cancel construction of a generic netlink message
* @skb: socket buffer the message is stored in
* @hdr: generic netlink message header
*/
static inline int genlmsg_cancel(struct sk_buff *skb, void *hdr)
{
return nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
}
/**
* genlmsg_multicast - multicast a netlink message
* @skb: netlink message as socket buffer
* @pid: own netlink pid to avoid sending to yourself
* @group: multicast group id
* @flags: allocation flags
*/
static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
unsigned int group, gfp_t flags)
{
return nlmsg_multicast(genl_sock, skb, pid, group, flags);
}
/**
* genlmsg_unicast - unicast a netlink message
* @skb: netlink message as socket buffer
* @pid: netlink pid of the destination socket
*/
static inline int genlmsg_unicast(struct sk_buff *skb, u32 pid)
{
return nlmsg_unicast(genl_sock, skb, pid);
}
/**
* gennlmsg_data - head of message payload
* @gnlh: genetlink messsage header
*/
static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
{
return ((unsigned char *) gnlh + GENL_HDRLEN);
}
/**
* genlmsg_len - length of message payload
* @gnlh: genetlink message header
*/
static inline int genlmsg_len(const struct genlmsghdr *gnlh)
{
struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
NLMSG_HDRLEN);
return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
}
#endif /* __NET_GENERIC_NETLINK_H */