xref: /linux/kernel/time/posix-stubs.c (revision e80a48bade619ec5a92230b3d4ae84bfc2746822)
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 #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
21 /* Architectures may override SYS_NI and COMPAT_SYS_NI */
22 #include <asm/syscall_wrapper.h>
23 #endif
24 
25 asmlinkage long sys_ni_posix_timers(void)
26 {
27 	pr_err_once("process %d (%s) attempted a POSIX timer syscall "
28 		    "while CONFIG_POSIX_TIMERS is not set\n",
29 		    current->pid, current->comm);
30 	return -ENOSYS;
31 }
32 
33 #ifndef SYS_NI
34 #define SYS_NI(name)  SYSCALL_ALIAS(sys_##name, sys_ni_posix_timers)
35 #endif
36 
37 #ifndef COMPAT_SYS_NI
38 #define COMPAT_SYS_NI(name)  SYSCALL_ALIAS(compat_sys_##name, sys_ni_posix_timers)
39 #endif
40 
41 SYS_NI(timer_create);
42 SYS_NI(timer_gettime);
43 SYS_NI(timer_getoverrun);
44 SYS_NI(timer_settime);
45 SYS_NI(timer_delete);
46 SYS_NI(clock_adjtime);
47 SYS_NI(getitimer);
48 SYS_NI(setitimer);
49 SYS_NI(clock_adjtime32);
50 #ifdef __ARCH_WANT_SYS_ALARM
51 SYS_NI(alarm);
52 #endif
53 
54 /*
55  * We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC
56  * as it is easy to remain compatible with little code. CLOCK_BOOTTIME
57  * is also included for convenience as at least systemd uses it.
58  */
59 
60 SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
61 		const struct __kernel_timespec __user *, tp)
62 {
63 	struct timespec64 new_tp;
64 
65 	if (which_clock != CLOCK_REALTIME)
66 		return -EINVAL;
67 	if (get_timespec64(&new_tp, tp))
68 		return -EFAULT;
69 
70 	return do_sys_settimeofday64(&new_tp, NULL);
71 }
72 
73 static int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
74 {
75 	switch (which_clock) {
76 	case CLOCK_REALTIME:
77 		ktime_get_real_ts64(tp);
78 		break;
79 	case CLOCK_MONOTONIC:
80 		ktime_get_ts64(tp);
81 		timens_add_monotonic(tp);
82 		break;
83 	case CLOCK_BOOTTIME:
84 		ktime_get_boottime_ts64(tp);
85 		timens_add_boottime(tp);
86 		break;
87 	default:
88 		return -EINVAL;
89 	}
90 
91 	return 0;
92 }
93 
94 SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
95 		struct __kernel_timespec __user *, tp)
96 {
97 	int ret;
98 	struct timespec64 kernel_tp;
99 
100 	ret = do_clock_gettime(which_clock, &kernel_tp);
101 	if (ret)
102 		return ret;
103 
104 	if (put_timespec64(&kernel_tp, tp))
105 		return -EFAULT;
106 	return 0;
107 }
108 
109 SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct __kernel_timespec __user *, tp)
110 {
111 	struct timespec64 rtn_tp = {
112 		.tv_sec = 0,
113 		.tv_nsec = hrtimer_resolution,
114 	};
115 
116 	switch (which_clock) {
117 	case CLOCK_REALTIME:
118 	case CLOCK_MONOTONIC:
119 	case CLOCK_BOOTTIME:
120 		if (put_timespec64(&rtn_tp, tp))
121 			return -EFAULT;
122 		return 0;
123 	default:
124 		return -EINVAL;
125 	}
126 }
127 
128 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
129 		const struct __kernel_timespec __user *, rqtp,
130 		struct __kernel_timespec __user *, rmtp)
131 {
132 	struct timespec64 t;
133 	ktime_t texp;
134 
135 	switch (which_clock) {
136 	case CLOCK_REALTIME:
137 	case CLOCK_MONOTONIC:
138 	case CLOCK_BOOTTIME:
139 		break;
140 	default:
141 		return -EINVAL;
142 	}
143 
144 	if (get_timespec64(&t, rqtp))
145 		return -EFAULT;
146 	if (!timespec64_valid(&t))
147 		return -EINVAL;
148 	if (flags & TIMER_ABSTIME)
149 		rmtp = NULL;
150 	current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
151 	current->restart_block.nanosleep.rmtp = rmtp;
152 	texp = timespec64_to_ktime(t);
153 	if (flags & TIMER_ABSTIME)
154 		texp = timens_ktime_to_host(which_clock, texp);
155 	return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
156 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
157 				 which_clock);
158 }
159 
160 #ifdef CONFIG_COMPAT
161 COMPAT_SYS_NI(timer_create);
162 #endif
163 
164 #if defined(CONFIG_COMPAT) || defined(CONFIG_ALPHA)
165 COMPAT_SYS_NI(getitimer);
166 COMPAT_SYS_NI(setitimer);
167 #endif
168 
169 #ifdef CONFIG_COMPAT_32BIT_TIME
170 SYS_NI(timer_settime32);
171 SYS_NI(timer_gettime32);
172 
173 SYSCALL_DEFINE2(clock_settime32, const clockid_t, which_clock,
174 		struct old_timespec32 __user *, tp)
175 {
176 	struct timespec64 new_tp;
177 
178 	if (which_clock != CLOCK_REALTIME)
179 		return -EINVAL;
180 	if (get_old_timespec32(&new_tp, tp))
181 		return -EFAULT;
182 
183 	return do_sys_settimeofday64(&new_tp, NULL);
184 }
185 
186 SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
187 		struct old_timespec32 __user *, tp)
188 {
189 	int ret;
190 	struct timespec64 kernel_tp;
191 
192 	ret = do_clock_gettime(which_clock, &kernel_tp);
193 	if (ret)
194 		return ret;
195 
196 	if (put_old_timespec32(&kernel_tp, tp))
197 		return -EFAULT;
198 	return 0;
199 }
200 
201 SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
202 		struct old_timespec32 __user *, tp)
203 {
204 	struct timespec64 rtn_tp = {
205 		.tv_sec = 0,
206 		.tv_nsec = hrtimer_resolution,
207 	};
208 
209 	switch (which_clock) {
210 	case CLOCK_REALTIME:
211 	case CLOCK_MONOTONIC:
212 	case CLOCK_BOOTTIME:
213 		if (put_old_timespec32(&rtn_tp, tp))
214 			return -EFAULT;
215 		return 0;
216 	default:
217 		return -EINVAL;
218 	}
219 }
220 
221 SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
222 		struct old_timespec32 __user *, rqtp,
223 		struct old_timespec32 __user *, rmtp)
224 {
225 	struct timespec64 t;
226 	ktime_t texp;
227 
228 	switch (which_clock) {
229 	case CLOCK_REALTIME:
230 	case CLOCK_MONOTONIC:
231 	case CLOCK_BOOTTIME:
232 		break;
233 	default:
234 		return -EINVAL;
235 	}
236 
237 	if (get_old_timespec32(&t, rqtp))
238 		return -EFAULT;
239 	if (!timespec64_valid(&t))
240 		return -EINVAL;
241 	if (flags & TIMER_ABSTIME)
242 		rmtp = NULL;
243 	current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
244 	current->restart_block.nanosleep.compat_rmtp = rmtp;
245 	texp = timespec64_to_ktime(t);
246 	if (flags & TIMER_ABSTIME)
247 		texp = timens_ktime_to_host(which_clock, texp);
248 	return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
249 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
250 				 which_clock);
251 }
252 #endif
253