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/nsproxy.h> 8 #include <linux/ns_common.h> 9 #include <linux/err.h> 10 11 struct user_namespace; 12 extern struct user_namespace init_user_ns; 13 14 struct timens_offsets { 15 struct timespec64 monotonic; 16 struct timespec64 boottime; 17 }; 18 19 struct time_namespace { 20 struct user_namespace *user_ns; 21 struct ucounts *ucounts; 22 struct ns_common ns; 23 struct timens_offsets offsets; 24 struct page *vvar_page; 25 /* If set prevents changing offsets after any task joined namespace. */ 26 bool frozen_offsets; 27 } __randomize_layout; 28 29 extern struct time_namespace init_time_ns; 30 31 #ifdef CONFIG_TIME_NS 32 extern int vdso_join_timens(struct task_struct *task, 33 struct time_namespace *ns); 34 extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); 35 36 static inline struct time_namespace *get_time_ns(struct time_namespace *ns) 37 { 38 refcount_inc(&ns->ns.count); 39 return ns; 40 } 41 42 struct time_namespace *copy_time_ns(unsigned long flags, 43 struct user_namespace *user_ns, 44 struct time_namespace *old_ns); 45 void free_time_ns(struct time_namespace *ns); 46 void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk); 47 struct vdso_data *arch_get_vdso_data(void *vvar_page); 48 49 static inline void put_time_ns(struct time_namespace *ns) 50 { 51 if (refcount_dec_and_test(&ns->ns.count)) 52 free_time_ns(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 static inline u64 timens_add_boottime_ns(u64 nsec) 80 { 81 struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; 82 83 return nsec + timespec64_to_ns(&ns_offsets->boottime); 84 } 85 86 static inline void timens_sub_boottime(struct timespec64 *ts) 87 { 88 struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; 89 90 *ts = timespec64_sub(*ts, ns_offsets->boottime); 91 } 92 93 ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim, 94 struct timens_offsets *offsets); 95 96 static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) 97 { 98 struct time_namespace *ns = current->nsproxy->time_ns; 99 100 if (likely(ns == &init_time_ns)) 101 return tim; 102 103 return do_timens_ktime_to_host(clockid, tim, &ns->offsets); 104 } 105 106 #else 107 static inline int vdso_join_timens(struct task_struct *task, 108 struct time_namespace *ns) 109 { 110 return 0; 111 } 112 113 static inline void timens_commit(struct task_struct *tsk, 114 struct time_namespace *ns) 115 { 116 } 117 118 static inline struct time_namespace *get_time_ns(struct time_namespace *ns) 119 { 120 return NULL; 121 } 122 123 static inline void put_time_ns(struct time_namespace *ns) 124 { 125 } 126 127 static inline 128 struct time_namespace *copy_time_ns(unsigned long flags, 129 struct user_namespace *user_ns, 130 struct time_namespace *old_ns) 131 { 132 if (flags & CLONE_NEWTIME) 133 return ERR_PTR(-EINVAL); 134 135 return old_ns; 136 } 137 138 static inline void timens_on_fork(struct nsproxy *nsproxy, 139 struct task_struct *tsk) 140 { 141 return; 142 } 143 144 static inline void timens_add_monotonic(struct timespec64 *ts) { } 145 static inline void timens_add_boottime(struct timespec64 *ts) { } 146 147 static inline u64 timens_add_boottime_ns(u64 nsec) 148 { 149 return nsec; 150 } 151 152 static inline void timens_sub_boottime(struct timespec64 *ts) { } 153 154 static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) 155 { 156 return tim; 157 } 158 #endif 159 160 #endif /* _LINUX_TIMENS_H */ 161