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 | #include <linux/time64.h> |
11 | |
12 | struct user_namespace; |
13 | extern struct user_namespace init_user_ns; |
14 | |
15 | struct vm_area_struct; |
16 | |
17 | struct timens_offsets { |
18 | struct timespec64 monotonic; |
19 | struct timespec64 boottime; |
20 | }; |
21 | |
22 | struct time_namespace { |
23 | struct user_namespace *user_ns; |
24 | struct ucounts *ucounts; |
25 | struct ns_common ns; |
26 | struct timens_offsets offsets; |
27 | struct page *vvar_page; |
28 | /* If set prevents changing offsets after any task joined namespace. */ |
29 | bool frozen_offsets; |
30 | } __randomize_layout; |
31 | |
32 | extern struct time_namespace init_time_ns; |
33 | |
34 | #ifdef CONFIG_TIME_NS |
35 | extern int vdso_join_timens(struct task_struct *task, |
36 | struct time_namespace *ns); |
37 | extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); |
38 | |
39 | static inline struct time_namespace *get_time_ns(struct time_namespace *ns) |
40 | { |
41 | refcount_inc(r: &ns->ns.count); |
42 | return ns; |
43 | } |
44 | |
45 | struct time_namespace *copy_time_ns(unsigned long flags, |
46 | struct user_namespace *user_ns, |
47 | struct time_namespace *old_ns); |
48 | void free_time_ns(struct time_namespace *ns); |
49 | void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk); |
50 | struct page *find_timens_vvar_page(struct vm_area_struct *vma); |
51 | |
52 | static inline void put_time_ns(struct time_namespace *ns) |
53 | { |
54 | if (refcount_dec_and_test(r: &ns->ns.count)) |
55 | free_time_ns(ns); |
56 | } |
57 | |
58 | void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m); |
59 | |
60 | struct proc_timens_offset { |
61 | int clockid; |
62 | struct timespec64 val; |
63 | }; |
64 | |
65 | int proc_timens_set_offset(struct file *file, struct task_struct *p, |
66 | struct proc_timens_offset *offsets, int n); |
67 | |
68 | static inline void timens_add_monotonic(struct timespec64 *ts) |
69 | { |
70 | struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; |
71 | |
72 | *ts = timespec64_add(lhs: *ts, rhs: ns_offsets->monotonic); |
73 | } |
74 | |
75 | static inline void timens_add_boottime(struct timespec64 *ts) |
76 | { |
77 | struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; |
78 | |
79 | *ts = timespec64_add(lhs: *ts, rhs: ns_offsets->boottime); |
80 | } |
81 | |
82 | static inline u64 timens_add_boottime_ns(u64 nsec) |
83 | { |
84 | struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; |
85 | |
86 | return nsec + timespec64_to_ns(ts: &ns_offsets->boottime); |
87 | } |
88 | |
89 | static inline void timens_sub_boottime(struct timespec64 *ts) |
90 | { |
91 | struct timens_offsets *ns_offsets = ¤t->nsproxy->time_ns->offsets; |
92 | |
93 | *ts = timespec64_sub(lhs: *ts, rhs: ns_offsets->boottime); |
94 | } |
95 | |
96 | ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim, |
97 | struct timens_offsets *offsets); |
98 | |
99 | static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) |
100 | { |
101 | struct time_namespace *ns = current->nsproxy->time_ns; |
102 | |
103 | if (likely(ns == &init_time_ns)) |
104 | return tim; |
105 | |
106 | return do_timens_ktime_to_host(clockid, tim, offsets: &ns->offsets); |
107 | } |
108 | |
109 | #else |
110 | static inline int vdso_join_timens(struct task_struct *task, |
111 | struct time_namespace *ns) |
112 | { |
113 | return 0; |
114 | } |
115 | |
116 | static inline void timens_commit(struct task_struct *tsk, |
117 | struct time_namespace *ns) |
118 | { |
119 | } |
120 | |
121 | static inline struct time_namespace *get_time_ns(struct time_namespace *ns) |
122 | { |
123 | return NULL; |
124 | } |
125 | |
126 | static inline void put_time_ns(struct time_namespace *ns) |
127 | { |
128 | } |
129 | |
130 | static inline |
131 | struct time_namespace *copy_time_ns(unsigned long flags, |
132 | struct user_namespace *user_ns, |
133 | struct time_namespace *old_ns) |
134 | { |
135 | if (flags & CLONE_NEWTIME) |
136 | return ERR_PTR(-EINVAL); |
137 | |
138 | return old_ns; |
139 | } |
140 | |
141 | static inline void timens_on_fork(struct nsproxy *nsproxy, |
142 | struct task_struct *tsk) |
143 | { |
144 | return; |
145 | } |
146 | |
147 | static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma) |
148 | { |
149 | return NULL; |
150 | } |
151 | |
152 | static inline void timens_add_monotonic(struct timespec64 *ts) { } |
153 | static inline void timens_add_boottime(struct timespec64 *ts) { } |
154 | |
155 | static inline u64 timens_add_boottime_ns(u64 nsec) |
156 | { |
157 | return nsec; |
158 | } |
159 | |
160 | static inline void timens_sub_boottime(struct timespec64 *ts) { } |
161 | |
162 | static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) |
163 | { |
164 | return tim; |
165 | } |
166 | #endif |
167 | |
168 | struct vdso_data *arch_get_vdso_data(void *vvar_page); |
169 | |
170 | #endif /* _LINUX_TIMENS_H */ |
171 | |