LXR linux/include/linux/utsname.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_UTSNAME_H
   3#define _LINUX_UTSNAME_H
   4
   5
   6#include <linux/sched.h>
   7#include <linux/nsproxy.h>
   8#include <linux/ns_common.h>
   9#include <linux/err.h>
  10#include <uapi/linux/utsname.h>
  11
  12enum uts_proc {
  13        UTS_PROC_OSTYPE,
  14        UTS_PROC_OSRELEASE,
  15        UTS_PROC_VERSION,
  16        UTS_PROC_HOSTNAME,
  17        UTS_PROC_DOMAINNAME,
  18};
  19
  20struct user_namespace;
  21extern struct user_namespace init_user_ns;
  22
  23struct uts_namespace {
  24        struct new_utsname name;
  25        struct user_namespace *user_ns;
  26        struct ucounts *ucounts;
  27        struct ns_common ns;
  28} __randomize_layout;
  29extern struct uts_namespace init_uts_ns;
  30
  31#ifdef CONFIG_UTS_NS
  32static inline void get_uts_ns(struct uts_namespace *ns)
  33{
  34        refcount_inc(&ns->ns.count);
  35}
  36
  37extern struct uts_namespace *copy_utsname(unsigned long flags,
  38        struct user_namespace *user_ns, struct uts_namespace *old_ns);
  39extern void free_uts_ns(struct uts_namespace *ns);
  40
  41static inline void put_uts_ns(struct uts_namespace *ns)
  42{
  43        if (refcount_dec_and_test(&ns->ns.count))
  44                free_uts_ns(ns);
  45}
  46
  47void uts_ns_init(void);
  48#else
  49static inline void get_uts_ns(struct uts_namespace *ns)
  50{
  51}
  52
  53static inline void put_uts_ns(struct uts_namespace *ns)
  54{
  55}
  56
  57static inline struct uts_namespace *copy_utsname(unsigned long flags,
  58        struct user_namespace *user_ns, struct uts_namespace *old_ns)
  59{
  60        if (flags & CLONE_NEWUTS)
  61                return ERR_PTR(-EINVAL);
  62
  63        return old_ns;
  64}
  65
  66static inline void uts_ns_init(void)
  67{
  68}
  69#endif
  70
  71#ifdef CONFIG_PROC_SYSCTL
  72extern void uts_proc_notify(enum uts_proc proc);
  73#else
  74static inline void uts_proc_notify(enum uts_proc proc)
  75{
  76}
  77#endif
  78
  79static inline struct new_utsname *utsname(void)
  80{
  81        return &current->nsproxy->uts_ns->name;
  82}
  83
  84static inline struct new_utsname *init_utsname(void)
  85{
  86        return &init_uts_ns.name;
  87}
  88
  89extern struct rw_semaphore uts_sem;
  90
  91#endif /* _LINUX_UTSNAME_H */
  92