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1#ifndef __NET_GENERIC_NETLINK_H
2#define __NET_GENERIC_NETLINK_H
3
4#include <linux/genetlink.h>
5#include <net/netlink.h>
6#include <net/net_namespace.h>
7
8/**
9 * struct genl_multicast_group - generic netlink multicast group
10 * @name: name of the multicast group, names are per-family
11 * @id: multicast group ID, assigned by the core, to use with
12 * genlmsg_multicast().
13 * @list: list entry for linking
14 * @family: pointer to family, need not be set before registering
15 */
16struct genl_multicast_group {
17 struct genl_family *family; /* private */
18 struct list_head list; /* private */
19 char name[GENL_NAMSIZ];
20 u32 id;
21};
22
23struct genl_ops;
24struct genl_info;
25
26/**
27 * struct genl_family - generic netlink family
28 * @id: protocol family idenfitier
29 * @hdrsize: length of user specific header in bytes
30 * @name: name of family
31 * @version: protocol version
32 * @maxattr: maximum number of attributes supported
33 * @netnsok: set to true if the family can handle network
34 * namespaces and should be presented in all of them
35 * @pre_doit: called before an operation's doit callback, it may
36 * do additional, common, filtering and return an error
37 * @post_doit: called after an operation's doit callback, it may
38 * undo operations done by pre_doit, for example release locks
39 * @attrbuf: buffer to store parsed attributes
40 * @ops_list: list of all assigned operations
41 * @family_list: family list
42 * @mcast_groups: multicast groups list
43 */
44struct genl_family {
45 unsigned int id;
46 unsigned int hdrsize;
47 char name[GENL_NAMSIZ];
48 unsigned int version;
49 unsigned int maxattr;
50 bool netnsok;
51 int (*pre_doit)(struct genl_ops *ops,
52 struct sk_buff *skb,
53 struct genl_info *info);
54 void (*post_doit)(struct genl_ops *ops,
55 struct sk_buff *skb,
56 struct genl_info *info);
57 struct nlattr ** attrbuf; /* private */
58 struct list_head ops_list; /* private */
59 struct list_head family_list; /* private */
60 struct list_head mcast_groups; /* private */
61};
62
63/**
64 * struct genl_info - receiving information
65 * @snd_seq: sending sequence number
66 * @snd_pid: netlink pid of sender
67 * @nlhdr: netlink message header
68 * @genlhdr: generic netlink message header
69 * @userhdr: user specific header
70 * @attrs: netlink attributes
71 * @_net: network namespace
72 * @user_ptr: user pointers
73 */
74struct genl_info {
75 u32 snd_seq;
76 u32 snd_pid;
77 struct nlmsghdr * nlhdr;
78 struct genlmsghdr * genlhdr;
79 void * userhdr;
80 struct nlattr ** attrs;
81#ifdef CONFIG_NET_NS
82 struct net * _net;
83#endif
84 void * user_ptr[2];
85};
86
87static inline struct net *genl_info_net(struct genl_info *info)
88{
89 return read_pnet(&info->_net);
90}
91
92static inline void genl_info_net_set(struct genl_info *info, struct net *net)
93{
94 write_pnet(&info->_net, net);
95}
96
97/**
98 * struct genl_ops - generic netlink operations
99 * @cmd: command identifier
100 * @internal_flags: flags used by the family
101 * @flags: flags
102 * @policy: attribute validation policy
103 * @doit: standard command callback
104 * @dumpit: callback for dumpers
105 * @done: completion callback for dumps
106 * @ops_list: operations list
107 */
108struct genl_ops {
109 u8 cmd;
110 u8 internal_flags;
111 unsigned int flags;
112 const struct nla_policy *policy;
113 int (*doit)(struct sk_buff *skb,
114 struct genl_info *info);
115 int (*dumpit)(struct sk_buff *skb,
116 struct netlink_callback *cb);
117 int (*done)(struct netlink_callback *cb);
118 struct list_head ops_list;
119};
120
121extern int genl_register_family(struct genl_family *family);
122extern int genl_register_family_with_ops(struct genl_family *family,
123 struct genl_ops *ops, size_t n_ops);
124extern int genl_unregister_family(struct genl_family *family);
125extern int genl_register_ops(struct genl_family *, struct genl_ops *ops);
126extern int genl_unregister_ops(struct genl_family *, struct genl_ops *ops);
127extern int genl_register_mc_group(struct genl_family *family,
128 struct genl_multicast_group *grp);
129extern void genl_unregister_mc_group(struct genl_family *family,
130 struct genl_multicast_group *grp);
131
132/**
133 * genlmsg_put - Add generic netlink header to netlink message
134 * @skb: socket buffer holding the message
135 * @pid: netlink pid the message is addressed to
136 * @seq: sequence number (usually the one of the sender)
137 * @family: generic netlink family
138 * @flags netlink message flags
139 * @cmd: generic netlink command
140 *
141 * Returns pointer to user specific header
142 */
143static inline void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
144 struct genl_family *family, int flags, u8 cmd)
145{
146 struct nlmsghdr *nlh;
147 struct genlmsghdr *hdr;
148
149 nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
150 family->hdrsize, flags);
151 if (nlh == NULL)
152 return NULL;
153
154 hdr = nlmsg_data(nlh);
155 hdr->cmd = cmd;
156 hdr->version = family->version;
157 hdr->reserved = 0;
158
159 return (char *) hdr + GENL_HDRLEN;
160}
161
162/**
163 * genlmsg_nlhdr - Obtain netlink header from user specified header
164 * @user_hdr: user header as returned from genlmsg_put()
165 * @family: generic netlink family
166 *
167 * Returns pointer to netlink header.
168 */
169static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
170 struct genl_family *family)
171{
172 return (struct nlmsghdr *)((char *)user_hdr -
173 family->hdrsize -
174 GENL_HDRLEN -
175 NLMSG_HDRLEN);
176}
177
178/**
179 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
180 * @cb: netlink callback structure that stores the sequence number
181 * @user_hdr: user header as returned from genlmsg_put()
182 * @family: generic netlink family
183 *
184 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
185 * simpler to use with generic netlink.
186 */
187static inline void genl_dump_check_consistent(struct netlink_callback *cb,
188 void *user_hdr,
189 struct genl_family *family)
190{
191 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
192}
193
194/**
195 * genlmsg_put_reply - Add generic netlink header to a reply message
196 * @skb: socket buffer holding the message
197 * @info: receiver info
198 * @family: generic netlink family
199 * @flags: netlink message flags
200 * @cmd: generic netlink command
201 *
202 * Returns pointer to user specific header
203 */
204static inline void *genlmsg_put_reply(struct sk_buff *skb,
205 struct genl_info *info,
206 struct genl_family *family,
207 int flags, u8 cmd)
208{
209 return genlmsg_put(skb, info->snd_pid, info->snd_seq, family,
210 flags, cmd);
211}
212
213/**
214 * genlmsg_end - Finalize a generic netlink message
215 * @skb: socket buffer the message is stored in
216 * @hdr: user specific header
217 */
218static inline int genlmsg_end(struct sk_buff *skb, void *hdr)
219{
220 return nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
221}
222
223/**
224 * genlmsg_cancel - Cancel construction of a generic netlink message
225 * @skb: socket buffer the message is stored in
226 * @hdr: generic netlink message header
227 */
228static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
229{
230 if (hdr)
231 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
232}
233
234/**
235 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
236 * @net: the net namespace
237 * @skb: netlink message as socket buffer
238 * @pid: own netlink pid to avoid sending to yourself
239 * @group: multicast group id
240 * @flags: allocation flags
241 */
242static inline int genlmsg_multicast_netns(struct net *net, struct sk_buff *skb,
243 u32 pid, unsigned int group, gfp_t flags)
244{
245 return nlmsg_multicast(net->genl_sock, skb, pid, group, flags);
246}
247
248/**
249 * genlmsg_multicast - multicast a netlink message to the default netns
250 * @skb: netlink message as socket buffer
251 * @pid: own netlink pid to avoid sending to yourself
252 * @group: multicast group id
253 * @flags: allocation flags
254 */
255static inline int genlmsg_multicast(struct sk_buff *skb, u32 pid,
256 unsigned int group, gfp_t flags)
257{
258 return genlmsg_multicast_netns(&init_net, skb, pid, group, flags);
259}
260
261/**
262 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
263 * @skb: netlink message as socket buffer
264 * @pid: own netlink pid to avoid sending to yourself
265 * @group: multicast group id
266 * @flags: allocation flags
267 *
268 * This function must hold the RTNL or rcu_read_lock().
269 */
270int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid,
271 unsigned int group, gfp_t flags);
272
273/**
274 * genlmsg_unicast - unicast a netlink message
275 * @skb: netlink message as socket buffer
276 * @pid: netlink pid of the destination socket
277 */
278static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 pid)
279{
280 return nlmsg_unicast(net->genl_sock, skb, pid);
281}
282
283/**
284 * genlmsg_reply - reply to a request
285 * @skb: netlink message to be sent back
286 * @info: receiver information
287 */
288static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
289{
290 return genlmsg_unicast(genl_info_net(info), skb, info->snd_pid);
291}
292
293/**
294 * gennlmsg_data - head of message payload
295 * @gnlh: genetlink message header
296 */
297static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
298{
299 return ((unsigned char *) gnlh + GENL_HDRLEN);
300}
301
302/**
303 * genlmsg_len - length of message payload
304 * @gnlh: genetlink message header
305 */
306static inline int genlmsg_len(const struct genlmsghdr *gnlh)
307{
308 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
309 NLMSG_HDRLEN);
310 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
311}
312
313/**
314 * genlmsg_msg_size - length of genetlink message not including padding
315 * @payload: length of message payload
316 */
317static inline int genlmsg_msg_size(int payload)
318{
319 return GENL_HDRLEN + payload;
320}
321
322/**
323 * genlmsg_total_size - length of genetlink message including padding
324 * @payload: length of message payload
325 */
326static inline int genlmsg_total_size(int payload)
327{
328 return NLMSG_ALIGN(genlmsg_msg_size(payload));
329}
330
331/**
332 * genlmsg_new - Allocate a new generic netlink message
333 * @payload: size of the message payload
334 * @flags: the type of memory to allocate.
335 */
336static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
337{
338 return nlmsg_new(genlmsg_total_size(payload), flags);
339}
340
341
342#endif /* __NET_GENERIC_NETLINK_H */
1#ifndef __NET_GENERIC_NETLINK_H
2#define __NET_GENERIC_NETLINK_H
3
4#include <linux/genetlink.h>
5#include <net/netlink.h>
6#include <net/net_namespace.h>
7
8#define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN)
9
10/**
11 * struct genl_multicast_group - generic netlink multicast group
12 * @name: name of the multicast group, names are per-family
13 */
14struct genl_multicast_group {
15 char name[GENL_NAMSIZ];
16};
17
18struct genl_ops;
19struct genl_info;
20
21/**
22 * struct genl_family - generic netlink family
23 * @id: protocol family idenfitier
24 * @hdrsize: length of user specific header in bytes
25 * @name: name of family
26 * @version: protocol version
27 * @maxattr: maximum number of attributes supported
28 * @netnsok: set to true if the family can handle network
29 * namespaces and should be presented in all of them
30 * @parallel_ops: operations can be called in parallel and aren't
31 * synchronized by the core genetlink code
32 * @pre_doit: called before an operation's doit callback, it may
33 * do additional, common, filtering and return an error
34 * @post_doit: called after an operation's doit callback, it may
35 * undo operations done by pre_doit, for example release locks
36 * @mcast_bind: a socket bound to the given multicast group (which
37 * is given as the offset into the groups array)
38 * @mcast_unbind: a socket was unbound from the given multicast group.
39 * Note that unbind() will not be called symmetrically if the
40 * generic netlink family is removed while there are still open
41 * sockets.
42 * @attrbuf: buffer to store parsed attributes
43 * @family_list: family list
44 * @mcgrps: multicast groups used by this family (private)
45 * @n_mcgrps: number of multicast groups (private)
46 * @mcgrp_offset: starting number of multicast group IDs in this family
47 * @ops: the operations supported by this family (private)
48 * @n_ops: number of operations supported by this family (private)
49 */
50struct genl_family {
51 unsigned int id;
52 unsigned int hdrsize;
53 char name[GENL_NAMSIZ];
54 unsigned int version;
55 unsigned int maxattr;
56 bool netnsok;
57 bool parallel_ops;
58 int (*pre_doit)(const struct genl_ops *ops,
59 struct sk_buff *skb,
60 struct genl_info *info);
61 void (*post_doit)(const struct genl_ops *ops,
62 struct sk_buff *skb,
63 struct genl_info *info);
64 int (*mcast_bind)(struct net *net, int group);
65 void (*mcast_unbind)(struct net *net, int group);
66 struct nlattr ** attrbuf; /* private */
67 const struct genl_ops * ops; /* private */
68 const struct genl_multicast_group *mcgrps; /* private */
69 unsigned int n_ops; /* private */
70 unsigned int n_mcgrps; /* private */
71 unsigned int mcgrp_offset; /* private */
72 struct list_head family_list; /* private */
73 struct module *module;
74};
75
76/**
77 * struct genl_info - receiving information
78 * @snd_seq: sending sequence number
79 * @snd_portid: netlink portid of sender
80 * @nlhdr: netlink message header
81 * @genlhdr: generic netlink message header
82 * @userhdr: user specific header
83 * @attrs: netlink attributes
84 * @_net: network namespace
85 * @user_ptr: user pointers
86 */
87struct genl_info {
88 u32 snd_seq;
89 u32 snd_portid;
90 struct nlmsghdr * nlhdr;
91 struct genlmsghdr * genlhdr;
92 void * userhdr;
93 struct nlattr ** attrs;
94 possible_net_t _net;
95 void * user_ptr[2];
96};
97
98static inline struct net *genl_info_net(struct genl_info *info)
99{
100 return read_pnet(&info->_net);
101}
102
103static inline void genl_info_net_set(struct genl_info *info, struct net *net)
104{
105 write_pnet(&info->_net, net);
106}
107
108/**
109 * struct genl_ops - generic netlink operations
110 * @cmd: command identifier
111 * @internal_flags: flags used by the family
112 * @flags: flags
113 * @policy: attribute validation policy
114 * @doit: standard command callback
115 * @start: start callback for dumps
116 * @dumpit: callback for dumpers
117 * @done: completion callback for dumps
118 * @ops_list: operations list
119 */
120struct genl_ops {
121 const struct nla_policy *policy;
122 int (*doit)(struct sk_buff *skb,
123 struct genl_info *info);
124 int (*start)(struct netlink_callback *cb);
125 int (*dumpit)(struct sk_buff *skb,
126 struct netlink_callback *cb);
127 int (*done)(struct netlink_callback *cb);
128 u8 cmd;
129 u8 internal_flags;
130 u8 flags;
131};
132
133int __genl_register_family(struct genl_family *family);
134
135static inline int genl_register_family(struct genl_family *family)
136{
137 family->module = THIS_MODULE;
138 return __genl_register_family(family);
139}
140
141/**
142 * genl_register_family_with_ops - register a generic netlink family with ops
143 * @family: generic netlink family
144 * @ops: operations to be registered
145 * @n_ops: number of elements to register
146 *
147 * Registers the specified family and operations from the specified table.
148 * Only one family may be registered with the same family name or identifier.
149 *
150 * The family id may equal GENL_ID_GENERATE causing an unique id to
151 * be automatically generated and assigned.
152 *
153 * Either a doit or dumpit callback must be specified for every registered
154 * operation or the function will fail. Only one operation structure per
155 * command identifier may be registered.
156 *
157 * See include/net/genetlink.h for more documenation on the operations
158 * structure.
159 *
160 * Return 0 on success or a negative error code.
161 */
162static inline int
163_genl_register_family_with_ops_grps(struct genl_family *family,
164 const struct genl_ops *ops, size_t n_ops,
165 const struct genl_multicast_group *mcgrps,
166 size_t n_mcgrps)
167{
168 family->module = THIS_MODULE;
169 family->ops = ops;
170 family->n_ops = n_ops;
171 family->mcgrps = mcgrps;
172 family->n_mcgrps = n_mcgrps;
173 return __genl_register_family(family);
174}
175
176#define genl_register_family_with_ops(family, ops) \
177 _genl_register_family_with_ops_grps((family), \
178 (ops), ARRAY_SIZE(ops), \
179 NULL, 0)
180#define genl_register_family_with_ops_groups(family, ops, grps) \
181 _genl_register_family_with_ops_grps((family), \
182 (ops), ARRAY_SIZE(ops), \
183 (grps), ARRAY_SIZE(grps))
184
185int genl_unregister_family(struct genl_family *family);
186void genl_notify(struct genl_family *family, struct sk_buff *skb,
187 struct genl_info *info, u32 group, gfp_t flags);
188
189void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
190 struct genl_family *family, int flags, u8 cmd);
191
192/**
193 * genlmsg_nlhdr - Obtain netlink header from user specified header
194 * @user_hdr: user header as returned from genlmsg_put()
195 * @family: generic netlink family
196 *
197 * Returns pointer to netlink header.
198 */
199static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
200 struct genl_family *family)
201{
202 return (struct nlmsghdr *)((char *)user_hdr -
203 family->hdrsize -
204 GENL_HDRLEN -
205 NLMSG_HDRLEN);
206}
207
208/**
209 * genlmsg_parse - parse attributes of a genetlink message
210 * @nlh: netlink message header
211 * @family: genetlink message family
212 * @tb: destination array with maxtype+1 elements
213 * @maxtype: maximum attribute type to be expected
214 * @policy: validation policy
215 * */
216static inline int genlmsg_parse(const struct nlmsghdr *nlh,
217 const struct genl_family *family,
218 struct nlattr *tb[], int maxtype,
219 const struct nla_policy *policy)
220{
221 return nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
222 policy);
223}
224
225/**
226 * genl_dump_check_consistent - check if sequence is consistent and advertise if not
227 * @cb: netlink callback structure that stores the sequence number
228 * @user_hdr: user header as returned from genlmsg_put()
229 * @family: generic netlink family
230 *
231 * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
232 * simpler to use with generic netlink.
233 */
234static inline void genl_dump_check_consistent(struct netlink_callback *cb,
235 void *user_hdr,
236 struct genl_family *family)
237{
238 nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
239}
240
241/**
242 * genlmsg_put_reply - Add generic netlink header to a reply message
243 * @skb: socket buffer holding the message
244 * @info: receiver info
245 * @family: generic netlink family
246 * @flags: netlink message flags
247 * @cmd: generic netlink command
248 *
249 * Returns pointer to user specific header
250 */
251static inline void *genlmsg_put_reply(struct sk_buff *skb,
252 struct genl_info *info,
253 struct genl_family *family,
254 int flags, u8 cmd)
255{
256 return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
257 flags, cmd);
258}
259
260/**
261 * genlmsg_end - Finalize a generic netlink message
262 * @skb: socket buffer the message is stored in
263 * @hdr: user specific header
264 */
265static inline void genlmsg_end(struct sk_buff *skb, void *hdr)
266{
267 nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
268}
269
270/**
271 * genlmsg_cancel - Cancel construction of a generic netlink message
272 * @skb: socket buffer the message is stored in
273 * @hdr: generic netlink message header
274 */
275static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
276{
277 if (hdr)
278 nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
279}
280
281/**
282 * genlmsg_multicast_netns - multicast a netlink message to a specific netns
283 * @family: the generic netlink family
284 * @net: the net namespace
285 * @skb: netlink message as socket buffer
286 * @portid: own netlink portid to avoid sending to yourself
287 * @group: offset of multicast group in groups array
288 * @flags: allocation flags
289 */
290static inline int genlmsg_multicast_netns(struct genl_family *family,
291 struct net *net, struct sk_buff *skb,
292 u32 portid, unsigned int group, gfp_t flags)
293{
294 if (WARN_ON_ONCE(group >= family->n_mcgrps))
295 return -EINVAL;
296 group = family->mcgrp_offset + group;
297 return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
298}
299
300/**
301 * genlmsg_multicast - multicast a netlink message to the default netns
302 * @family: the generic netlink family
303 * @skb: netlink message as socket buffer
304 * @portid: own netlink portid to avoid sending to yourself
305 * @group: offset of multicast group in groups array
306 * @flags: allocation flags
307 */
308static inline int genlmsg_multicast(struct genl_family *family,
309 struct sk_buff *skb, u32 portid,
310 unsigned int group, gfp_t flags)
311{
312 return genlmsg_multicast_netns(family, &init_net, skb,
313 portid, group, flags);
314}
315
316/**
317 * genlmsg_multicast_allns - multicast a netlink message to all net namespaces
318 * @family: the generic netlink family
319 * @skb: netlink message as socket buffer
320 * @portid: own netlink portid to avoid sending to yourself
321 * @group: offset of multicast group in groups array
322 * @flags: allocation flags
323 *
324 * This function must hold the RTNL or rcu_read_lock().
325 */
326int genlmsg_multicast_allns(struct genl_family *family,
327 struct sk_buff *skb, u32 portid,
328 unsigned int group, gfp_t flags);
329
330/**
331 * genlmsg_unicast - unicast a netlink message
332 * @skb: netlink message as socket buffer
333 * @portid: netlink portid of the destination socket
334 */
335static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
336{
337 return nlmsg_unicast(net->genl_sock, skb, portid);
338}
339
340/**
341 * genlmsg_reply - reply to a request
342 * @skb: netlink message to be sent back
343 * @info: receiver information
344 */
345static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
346{
347 return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
348}
349
350/**
351 * gennlmsg_data - head of message payload
352 * @gnlh: genetlink message header
353 */
354static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
355{
356 return ((unsigned char *) gnlh + GENL_HDRLEN);
357}
358
359/**
360 * genlmsg_len - length of message payload
361 * @gnlh: genetlink message header
362 */
363static inline int genlmsg_len(const struct genlmsghdr *gnlh)
364{
365 struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
366 NLMSG_HDRLEN);
367 return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
368}
369
370/**
371 * genlmsg_msg_size - length of genetlink message not including padding
372 * @payload: length of message payload
373 */
374static inline int genlmsg_msg_size(int payload)
375{
376 return GENL_HDRLEN + payload;
377}
378
379/**
380 * genlmsg_total_size - length of genetlink message including padding
381 * @payload: length of message payload
382 */
383static inline int genlmsg_total_size(int payload)
384{
385 return NLMSG_ALIGN(genlmsg_msg_size(payload));
386}
387
388/**
389 * genlmsg_new - Allocate a new generic netlink message
390 * @payload: size of the message payload
391 * @flags: the type of memory to allocate.
392 */
393static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
394{
395 return nlmsg_new(genlmsg_total_size(payload), flags);
396}
397
398/**
399 * genl_set_err - report error to genetlink broadcast listeners
400 * @family: the generic netlink family
401 * @net: the network namespace to report the error to
402 * @portid: the PORTID of a process that we want to skip (if any)
403 * @group: the broadcast group that will notice the error
404 * (this is the offset of the multicast group in the groups array)
405 * @code: error code, must be negative (as usual in kernelspace)
406 *
407 * This function returns the number of broadcast listeners that have set the
408 * NETLINK_RECV_NO_ENOBUFS socket option.
409 */
410static inline int genl_set_err(struct genl_family *family, struct net *net,
411 u32 portid, u32 group, int code)
412{
413 if (WARN_ON_ONCE(group >= family->n_mcgrps))
414 return -EINVAL;
415 group = family->mcgrp_offset + group;
416 return netlink_set_err(net->genl_sock, portid, group, code);
417}
418
419static inline int genl_has_listeners(struct genl_family *family,
420 struct net *net, unsigned int group)
421{
422 if (WARN_ON_ONCE(group >= family->n_mcgrps))
423 return -EINVAL;
424 group = family->mcgrp_offset + group;
425 return netlink_has_listeners(net->genl_sock, group);
426}
427#endif /* __NET_GENERIC_NETLINK_H */