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 enum uts_proc {
  41         UTS_PROC_OSTYPE,
  42         UTS_PROC_OSRELEASE,
  43         UTS_PROC_VERSION,
  44         UTS_PROC_HOSTNAME,
  45         UTS_PROC_DOMAINNAME,
  46 };
  47
  48 struct user_namespace;
  49 extern struct user_namespace init_user_ns;
  50
  51 struct uts_namespace {
  52         struct kref kref;
  53         struct new_utsname name;
  54         struct user_namespace *user_ns;
  55 };
  56 extern struct uts_namespace init_uts_ns;
  57
  58 #ifdef CONFIG_UTS_NS
  59 static inline void get_uts_ns(struct uts_namespace *ns)
  60 {
  61         kref_get(&ns->kref);
  62 }
  63
  64 extern struct uts_namespace *copy_utsname(unsigned long flags,
  65                                           struct task_struct *tsk);
  66 extern void free_uts_ns(struct kref *kref);
  67
  68 static inline void put_uts_ns(struct uts_namespace *ns)
  69 {
  70         kref_put(&ns->kref, free_uts_ns);
  71 }
  72 #else
  73 static inline void get_uts_ns(struct uts_namespace *ns)
  74 {
  75 }
  76
  77 static inline void put_uts_ns(struct uts_namespace *ns)
  78 {
  79 }
  80
  81 static inline struct uts_namespace *copy_utsname(unsigned long flags,
  82                                                  struct task_struct *tsk)
  83 {
  84         if (flags & CLONE_NEWUTS)
  85                 return ERR_PTR(-EINVAL);
  86
  87         return tsk->nsproxy->uts_ns;
  88 }
  89 #endif
  90
  91 #ifdef CONFIG_PROC_SYSCTL
  92 extern void uts_proc_notify(enum uts_proc proc);
  93 #else
  94 static inline void uts_proc_notify(enum uts_proc proc)
  95 {
  96 }
  97 #endif
  98
  99 static inline struct new_utsname *utsname(void)
 100 {
 101         return &current->nsproxy->uts_ns->name;
 102 }
 103
 104 static inline struct new_utsname *init_utsname(void)
 105 {
 106         return &init_uts_ns.name;
 107 }
 108
 109 extern struct rw_semaphore uts_sem;
 110
 111 #endif /* __KERNEL__ */
 112
 113 #endif /* _LINUX_UTSNAME_H */