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[__NEW_UTS_LEN + 1];
  26         char nodename[__NEW_UTS_LEN + 1];
  27         char release[__NEW_UTS_LEN + 1];
  28         char version[__NEW_UTS_LEN + 1];
  29         char machine[__NEW_UTS_LEN + 1];
  30         char domainname[__NEW_UTS_LEN + 1];
  31 };
  32
  33 #ifdef __KERNEL__
  34
  35 #include <linux/sched.h>
  36 #include <linux/kref.h>
  37 #include <linux/nsproxy.h>
  38 #include <linux/err.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 #ifdef CONFIG_UTS_NS
  47 static inline void get_uts_ns(struct uts_namespace *ns)
  48 {
  49         kref_get(&ns->kref);
  50 }
  51
  52 extern struct uts_namespace *copy_utsname(unsigned long flags,
  53                                         struct uts_namespace *ns);
  54 extern void free_uts_ns(struct kref *kref);
  55
  56 static inline void put_uts_ns(struct uts_namespace *ns)
  57 {
  58         kref_put(&ns->kref, free_uts_ns);
  59 }
  60 #else
  61 static inline void get_uts_ns(struct uts_namespace *ns)
  62 {
  63 }
  64
  65 static inline void put_uts_ns(struct uts_namespace *ns)
  66 {
  67 }
  68
  69 static inline struct uts_namespace *copy_utsname(unsigned long flags,
  70                                         struct uts_namespace *ns)
  71 {
  72         if (flags & CLONE_NEWUTS)
  73                 return ERR_PTR(-EINVAL);
  74
  75         return ns;
  76 }
  77 #endif
  78
  79 static inline struct new_utsname *utsname(void)
  80 {
  81         return &current->nsproxy->uts_ns->name;
  82 }
  83
  84 static inline struct new_utsname *init_utsname(void)
  85 {
  86         return &init_uts_ns.name;
  87 }
  88
  89 extern struct rw_semaphore uts_sem;
  90
  91 #endif /* __KERNEL__ */
  92
  93 #endif /* _LINUX_UTSNAME_H */