1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Dummy stubs used when CONFIG_POSIX_TIMERS=n
4 *
5 * Created by: Nicolas Pitre, July 2016
6 * Copyright: (C) 2016 Linaro Limited
7 */
8
9#include <linux/linkage.h>
10#include <linux/kernel.h>
11#include <linux/sched.h>
12#include <linux/errno.h>
13#include <linux/syscalls.h>
14#include <linux/ktime.h>
15#include <linux/timekeeping.h>
16#include <linux/posix-timers.h>
17#include <linux/time_namespace.h>
18#include <linux/compat.h>
19
20/*
21 * We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC
22 * as it is easy to remain compatible with little code. CLOCK_BOOTTIME
23 * is also included for convenience as at least systemd uses it.
24 */
25
26SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
27 const struct __kernel_timespec __user *, tp)
28{
29 struct timespec64 new_tp;
30
31 if (which_clock != CLOCK_REALTIME)
32 return -EINVAL;
33 if (get_timespec64(ts: &new_tp, uts: tp))
34 return -EFAULT;
35
36 return do_sys_settimeofday64(tv: &new_tp, NULL);
37}
38
39static int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
40{
41 switch (which_clock) {
42 case CLOCK_REALTIME:
43 ktime_get_real_ts64(tv: tp);
44 break;
45 case CLOCK_MONOTONIC:
46 ktime_get_ts64(ts: tp);
47 timens_add_monotonic(ts: tp);
48 break;
49 case CLOCK_BOOTTIME:
50 ktime_get_boottime_ts64(ts: tp);
51 timens_add_boottime(ts: tp);
52 break;
53 default:
54 return -EINVAL;
55 }
56
57 return 0;
58}
59
60SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
61 struct __kernel_timespec __user *, tp)
62{
63 int ret;
64 struct timespec64 kernel_tp;
65
66 ret = do_clock_gettime(which_clock, tp: &kernel_tp);
67 if (ret)
68 return ret;
69
70 if (put_timespec64(ts: &kernel_tp, uts: tp))
71 return -EFAULT;
72 return 0;
73}
74
75SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct __kernel_timespec __user *, tp)
76{
77 struct timespec64 rtn_tp = {
78 .tv_sec = 0,
79 .tv_nsec = hrtimer_resolution,
80 };
81
82 switch (which_clock) {
83 case CLOCK_REALTIME:
84 case CLOCK_MONOTONIC:
85 case CLOCK_BOOTTIME:
86 if (put_timespec64(ts: &rtn_tp, uts: tp))
87 return -EFAULT;
88 return 0;
89 default:
90 return -EINVAL;
91 }
92}
93
94SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
95 const struct __kernel_timespec __user *, rqtp,
96 struct __kernel_timespec __user *, rmtp)
97{
98 struct timespec64 t;
99 ktime_t texp;
100
101 switch (which_clock) {
102 case CLOCK_REALTIME:
103 case CLOCK_MONOTONIC:
104 case CLOCK_BOOTTIME:
105 break;
106 default:
107 return -EINVAL;
108 }
109
110 if (get_timespec64(ts: &t, uts: rqtp))
111 return -EFAULT;
112 if (!timespec64_valid(ts: &t))
113 return -EINVAL;
114 if (flags & TIMER_ABSTIME)
115 rmtp = NULL;
116 current->restart_block.fn = do_no_restart_syscall;
117 current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
118 current->restart_block.nanosleep.rmtp = rmtp;
119 texp = timespec64_to_ktime(ts: t);
120 if (flags & TIMER_ABSTIME)
121 texp = timens_ktime_to_host(clockid: which_clock, tim: texp);
122 return hrtimer_nanosleep(rqtp: texp, mode: flags & TIMER_ABSTIME ?
123 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
124 clockid: which_clock);
125}
126
127#ifdef CONFIG_COMPAT_32BIT_TIME
128
129SYSCALL_DEFINE2(clock_settime32, const clockid_t, which_clock,
130 struct old_timespec32 __user *, tp)
131{
132 struct timespec64 new_tp;
133
134 if (which_clock != CLOCK_REALTIME)
135 return -EINVAL;
136 if (get_old_timespec32(&new_tp, tp))
137 return -EFAULT;
138
139 return do_sys_settimeofday64(tv: &new_tp, NULL);
140}
141
142SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
143 struct old_timespec32 __user *, tp)
144{
145 int ret;
146 struct timespec64 kernel_tp;
147
148 ret = do_clock_gettime(which_clock, tp: &kernel_tp);
149 if (ret)
150 return ret;
151
152 if (put_old_timespec32(&kernel_tp, tp))
153 return -EFAULT;
154 return 0;
155}
156
157SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
158 struct old_timespec32 __user *, tp)
159{
160 struct timespec64 rtn_tp = {
161 .tv_sec = 0,
162 .tv_nsec = hrtimer_resolution,
163 };
164
165 switch (which_clock) {
166 case CLOCK_REALTIME:
167 case CLOCK_MONOTONIC:
168 case CLOCK_BOOTTIME:
169 if (put_old_timespec32(&rtn_tp, tp))
170 return -EFAULT;
171 return 0;
172 default:
173 return -EINVAL;
174 }
175}
176
177SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
178 struct old_timespec32 __user *, rqtp,
179 struct old_timespec32 __user *, rmtp)
180{
181 struct timespec64 t;
182 ktime_t texp;
183
184 switch (which_clock) {
185 case CLOCK_REALTIME:
186 case CLOCK_MONOTONIC:
187 case CLOCK_BOOTTIME:
188 break;
189 default:
190 return -EINVAL;
191 }
192
193 if (get_old_timespec32(&t, rqtp))
194 return -EFAULT;
195 if (!timespec64_valid(ts: &t))
196 return -EINVAL;
197 if (flags & TIMER_ABSTIME)
198 rmtp = NULL;
199 current->restart_block.fn = do_no_restart_syscall;
200 current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
201 current->restart_block.nanosleep.compat_rmtp = rmtp;
202 texp = timespec64_to_ktime(ts: t);
203 if (flags & TIMER_ABSTIME)
204 texp = timens_ktime_to_host(clockid: which_clock, tim: texp);
205 return hrtimer_nanosleep(rqtp: texp, mode: flags & TIMER_ABSTIME ?
206 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
207 clockid: which_clock);
208}
209#endif
210

source code of linux/kernel/time/posix-stubs.c