include/linux/utsname.h

   1 #ifndef _LINUX_UTSNAME_H
   2 #define _LINUX_UTSNAME_H
   3
   4 #define __OLD_UTS_LEN 8
   5
   6 struct oldold_utsname {
   7         char sysname[9];
   8         char nodename[9];
   9         char release[9];
  10         char version[9];
  11         char machine[9];
  12 };
  13
  14 #define __NEW_UTS_LEN 64
  15
  16 struct old_utsname {
  17         char sysname[65];
  18         char nodename[65];
  19         char release[65];
  20         char version[65];
  21         char machine[65];
  22 };
  23
  24 struct new_utsname {
  25         char sysname[65];
  26         char nodename[65];
  27         char release[65];
  28         char version[65];
  29         char machine[65];
  30         char domainname[65];
  31 };
  32
  33 #ifdef __KERNEL__
  34
  35 #include <linux/sched.h>
  36 #include <linux/kref.h>
  37 #include <linux/nsproxy.h>
  38 #include <asm/atomic.h>
  39
  40 struct uts_namespace {
  41         struct kref kref;
  42         struct new_utsname name;
  43 };
  44 extern struct uts_namespace init_uts_ns;
  45
  46 static inline void get_uts_ns(struct uts_namespace *ns)
  47 {
  48         kref_get(&ns->kref);
  49 }
  50
  51 #ifdef CONFIG_UTS_NS
  52 extern int unshare_utsname(unsigned long unshare_flags,
  53                                 struct uts_namespace **new_uts);
  54 extern int copy_utsname(int flags, struct task_struct *tsk);
  55 extern void free_uts_ns(struct kref *kref);
  56
  57 static inline void put_uts_ns(struct uts_namespace *ns)
  58 {
  59         kref_put(&ns->kref, free_uts_ns);
  60 }
  61 #else
  62 static inline int unshare_utsname(unsigned long unshare_flags,
  63                         struct uts_namespace **new_uts)
  64 {
  65         if (unshare_flags & CLONE_NEWUTS)
  66                 return -EINVAL;
  67
  68         return 0;
  69 }
  70
  71 static inline int copy_utsname(int flags, struct task_struct *tsk)
  72 {
  73         return 0;
  74 }
  75 static inline void put_uts_ns(struct uts_namespace *ns)
  76 {
  77 }
  78 #endif
  79
  80 static inline struct new_utsname *utsname(void)
  81 {
  82         return &current->nsproxy->uts_ns->name;
  83 }
  84
  85 static inline struct new_utsname *init_utsname(void)
  86 {
  87         return &init_uts_ns.name;
  88 }
  89
  90 extern struct rw_semaphore uts_sem;
  91
  92 #endif /* __KERNEL__ */
  93
  94 #endif /* _LINUX_UTSNAME_H */