1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_TIMENS_H 3 #define _LINUX_TIMENS_H 4 5 6 #include <linux/sched.h> 7 #include <linux/kref.h> 8 #include <linux/nsproxy.h> 9 #include <linux/ns_common.h> 10 #include <linux/err.h> 11 12 struct user_namespace; 13 extern struct user_namespace init_user_ns; 14 15 struct timens_offsets { 16 struct timespec64 monotonic; 17 struct timespec64 boottime; 18 }; 19 20 struct time_namespace { 21 struct kref kref; 22 struct user_namespace *user_ns; 23 struct ucounts *ucounts; 24 struct ns_common ns; 25 struct timens_offsets offsets; 26 struct page *vvar_page; 27 /* If set prevents changing offsets after any task joined namespace. */ 28 bool frozen_offsets; 29 } __randomize_layout; 30 31 extern struct time_namespace init_time_ns; 32 33 #ifdef CONFIG_TIME_NS 34 extern int vdso_join_timens(struct task_struct *task, 35 struct time_namespace *ns); 36 37 static inline struct time_namespace *get_time_ns(struct time_namespace *ns) 38 { 39 kref_get(&ns->kref); 40 return ns; 41 } 42 43 struct time_namespace *copy_time_ns(unsigned long flags, 44 struct user_namespace *user_ns, 45 struct time_namespace *old_ns); 46 void free_time_ns(struct kref *kref); 47 int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk); 48 struct vdso_data *arch_get_vdso_data(void *vvar_page); 49 50 static inline void put_time_ns(struct time_namespace *ns) 51 { 52 kref_put(&ns->kref, free_time_ns); 53 } 54 55 void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m); 56 57 struct proc_timens_offset { 58 int clockid; 59 struct timespec64 val; 60 }; 61 62 int proc_timens_set_offset(struct file *file, struct task_struct *p, 63 struct proc_timens_offset *offsets, int n); 64 65 static inline void timens_add_monotonic(struct timespec64 *ts) 66 { 67 struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; 68 69 *ts = timespec64_add(*ts, ns_offsets->monotonic); 70 } 71 72 static inline void timens_add_boottime(struct timespec64 *ts) 73 { 74 struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; 75 76 *ts = timespec64_add(*ts, ns_offsets->boottime); 77 } 78 79 ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim, 80 struct timens_offsets *offsets); 81 82 static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) 83 { 84 struct time_namespace *ns = current->nsproxy->time_ns; 85 86 if (likely(ns == &init_time_ns)) 87 return tim; 88 89 return do_timens_ktime_to_host(clockid, tim, &ns->offsets); 90 } 91 92 #else 93 static inline int vdso_join_timens(struct task_struct *task, 94 struct time_namespace *ns) 95 { 96 return 0; 97 } 98 99 static inline struct time_namespace *get_time_ns(struct time_namespace *ns) 100 { 101 return NULL; 102 } 103 104 static inline void put_time_ns(struct time_namespace *ns) 105 { 106 } 107 108 static inline 109 struct time_namespace *copy_time_ns(unsigned long flags, 110 struct user_namespace *user_ns, 111 struct time_namespace *old_ns) 112 { 113 if (flags & CLONE_NEWTIME) 114 return ERR_PTR(-EINVAL); 115 116 return old_ns; 117 } 118 119 static inline int timens_on_fork(struct nsproxy *nsproxy, 120 struct task_struct *tsk) 121 { 122 return 0; 123 } 124 125 static inline void timens_add_monotonic(struct timespec64 *ts) { } 126 static inline void timens_add_boottime(struct timespec64 *ts) { } 127 static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) 128 { 129 return tim; 130 } 131 #endif 132 133 #endif /* _LINUX_TIMENS_H */ 134