1#ifndef _LINUX_UTSNAME_H
2#define _LINUX_UTSNAME_H
3
4
5#include <linux/sched.h>
6#include <linux/kref.h>
7#include <linux/nsproxy.h>
8#include <linux/ns_common.h>
9#include <linux/err.h>
10#include <uapi/linux/utsname.h>
11
12enum uts_proc {
13	UTS_PROC_OSTYPE,
14	UTS_PROC_OSRELEASE,
15	UTS_PROC_VERSION,
16	UTS_PROC_HOSTNAME,
17	UTS_PROC_DOMAINNAME,
18};
19
20struct user_namespace;
21extern struct user_namespace init_user_ns;
22
23struct uts_namespace {
24	struct kref kref;
25	struct new_utsname name;
26	struct user_namespace *user_ns;
27	struct ns_common ns;
28};
29extern struct uts_namespace init_uts_ns;
30
31#ifdef CONFIG_UTS_NS
32static inline void get_uts_ns(struct uts_namespace *ns)
33{
34	kref_get(&ns->kref);
35}
36
37extern struct uts_namespace *copy_utsname(unsigned long flags,
38	struct user_namespace *user_ns, struct uts_namespace *old_ns);
39extern void free_uts_ns(struct kref *kref);
40
41static inline void put_uts_ns(struct uts_namespace *ns)
42{
43	kref_put(&ns->kref, free_uts_ns);
44}
45#else
46static inline void get_uts_ns(struct uts_namespace *ns)
47{
48}
49
50static inline void put_uts_ns(struct uts_namespace *ns)
51{
52}
53
54static inline struct uts_namespace *copy_utsname(unsigned long flags,
55	struct user_namespace *user_ns, struct uts_namespace *old_ns)
56{
57	if (flags & CLONE_NEWUTS)
58		return ERR_PTR(-EINVAL);
59
60	return old_ns;
61}
62#endif
63
64#ifdef CONFIG_PROC_SYSCTL
65extern void uts_proc_notify(enum uts_proc proc);
66#else
67static inline void uts_proc_notify(enum uts_proc proc)
68{
69}
70#endif
71
72static inline struct new_utsname *utsname(void)
73{
74	return &current->nsproxy->uts_ns->name;
75}
76
77static inline struct new_utsname *init_utsname(void)
78{
79	return &init_uts_ns.name;
80}
81
82extern struct rw_semaphore uts_sem;
83
84#endif /* _LINUX_UTSNAME_H */
85