include/linux/utsname.h

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