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 #include <asm/atomic.h>
  40
  41 struct uts_namespace {
  42         struct kref kref;
  43         struct new_utsname name;
  44 };
  45 extern struct uts_namespace init_uts_ns;
  46
  47 #ifdef CONFIG_UTS_NS
  48 static inline void get_uts_ns(struct uts_namespace *ns)
  49 {
  50         kref_get(&ns->kref);
  51 }
  52
  53 extern struct uts_namespace *copy_utsname(unsigned long flags,
  54                                         struct uts_namespace *ns);
  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 void get_uts_ns(struct uts_namespace *ns)
  63 {
  64 }
  65
  66 static inline void put_uts_ns(struct uts_namespace *ns)
  67 {
  68 }
  69
  70 static inline struct uts_namespace *copy_utsname(unsigned long flags,
  71                                         struct uts_namespace *ns)
  72 {
  73         if (flags & CLONE_NEWUTS)
  74                 return ERR_PTR(-EINVAL);
  75
  76         return ns;
  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 */