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(r: &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 page *find_timens_vvar_page(struct vm_area_struct *vma); |
48 | |
49 | static inline void put_time_ns(struct time_namespace *ns) |
50 | { |
51 | if (refcount_dec_and_test(r: &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(lhs: *ts, rhs: 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(lhs: *ts, rhs: 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(ts: &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(lhs: *ts, rhs: 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, offsets: &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 struct page *find_timens_vvar_page(struct vm_area_struct *vma) |
145 | { |
146 | return NULL; |
147 | } |
148 | |
149 | static inline void timens_add_monotonic(struct timespec64 *ts) { } |
150 | static inline void timens_add_boottime(struct timespec64 *ts) { } |
151 | |
152 | static inline u64 timens_add_boottime_ns(u64 nsec) |
153 | { |
154 | return nsec; |
155 | } |
156 | |
157 | static inline void timens_sub_boottime(struct timespec64 *ts) { } |
158 | |
159 | static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) |
160 | { |
161 | return tim; |
162 | } |
163 | #endif |
164 | |
165 | struct vdso_data *arch_get_vdso_data(void *vvar_page); |
166 | |
167 | #endif /* _LINUX_TIMENS_H */ |
168 | |