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 12 enum uts_proc { 13 UTS_PROC_OSTYPE, 14 UTS_PROC_OSRELEASE, 15 UTS_PROC_VERSION, 16 UTS_PROC_HOSTNAME, 17 UTS_PROC_DOMAINNAME, 18 }; 19 20 struct user_namespace; 21 extern struct user_namespace init_user_ns; 22 23 struct 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; 29 extern struct uts_namespace init_uts_ns; 30 31 #ifdef CONFIG_UTS_NS 32 static inline void get_uts_ns(struct uts_namespace *ns) 33 { 34 refcount_inc(&ns->ns.count); 35 } 36 37 extern struct uts_namespace *copy_utsname(unsigned long flags, 38 struct user_namespace *user_ns, struct uts_namespace *old_ns); 39 extern void free_uts_ns(struct uts_namespace *ns); 40 41 static 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 47 void uts_ns_init(void); 48 #else 49 static inline void get_uts_ns(struct uts_namespace *ns) 50 { 51 } 52 53 static inline void put_uts_ns(struct uts_namespace *ns) 54 { 55 } 56 57 static 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 66 static inline void uts_ns_init(void) 67 { 68 } 69 #endif 70 71 #ifdef CONFIG_PROC_SYSCTL 72 extern void uts_proc_notify(enum uts_proc proc); 73 #else 74 static inline void uts_proc_notify(enum uts_proc proc) 75 { 76 } 77 #endif 78 79 static inline struct new_utsname *utsname(void) 80 { 81 return ¤t->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 /* _LINUX_UTSNAME_H */ 92