xref: /linux/kernel/time/posix-stubs.c (revision 3bdab16c55f57a24245c97d707241dd9b48d1a91)
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/compat.h>
18 
19 #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
20 /* Architectures may override SYS_NI and COMPAT_SYS_NI */
21 #include <asm/syscall_wrapper.h>
22 #endif
23 
24 asmlinkage long sys_ni_posix_timers(void)
25 {
26 	pr_err_once("process %d (%s) attempted a POSIX timer syscall "
27 		    "while CONFIG_POSIX_TIMERS is not set\n",
28 		    current->pid, current->comm);
29 	return -ENOSYS;
30 }
31 
32 #ifndef SYS_NI
33 #define SYS_NI(name)  SYSCALL_ALIAS(sys_##name, sys_ni_posix_timers)
34 #endif
35 
36 #ifndef COMPAT_SYS_NI
37 #define COMPAT_SYS_NI(name)  SYSCALL_ALIAS(compat_sys_##name, sys_ni_posix_timers)
38 #endif
39 
40 SYS_NI(timer_create);
41 SYS_NI(timer_gettime);
42 SYS_NI(timer_getoverrun);
43 SYS_NI(timer_settime);
44 SYS_NI(timer_delete);
45 SYS_NI(clock_adjtime);
46 SYS_NI(getitimer);
47 SYS_NI(setitimer);
48 SYS_NI(clock_adjtime32);
49 #ifdef __ARCH_WANT_SYS_ALARM
50 SYS_NI(alarm);
51 #endif
52 
53 /*
54  * We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC
55  * as it is easy to remain compatible with little code. CLOCK_BOOTTIME
56  * is also included for convenience as at least systemd uses it.
57  */
58 
59 SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
60 		const struct __kernel_timespec __user *, tp)
61 {
62 	struct timespec64 new_tp;
63 
64 	if (which_clock != CLOCK_REALTIME)
65 		return -EINVAL;
66 	if (get_timespec64(&new_tp, tp))
67 		return -EFAULT;
68 
69 	return do_sys_settimeofday64(&new_tp, NULL);
70 }
71 
72 int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
73 {
74 	switch (which_clock) {
75 	case CLOCK_REALTIME:
76 		ktime_get_real_ts64(tp);
77 		break;
78 	case CLOCK_MONOTONIC:
79 		ktime_get_ts64(tp);
80 		break;
81 	case CLOCK_BOOTTIME:
82 		ktime_get_boottime_ts64(tp);
83 		break;
84 	default:
85 		return -EINVAL;
86 	}
87 
88 	return 0;
89 }
90 SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
91 		struct __kernel_timespec __user *, tp)
92 {
93 	int ret;
94 	struct timespec64 kernel_tp;
95 
96 	ret = do_clock_gettime(which_clock, &kernel_tp);
97 	if (ret)
98 		return ret;
99 
100 	if (put_timespec64(&kernel_tp, tp))
101 		return -EFAULT;
102 	return 0;
103 }
104 
105 SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct __kernel_timespec __user *, tp)
106 {
107 	struct timespec64 rtn_tp = {
108 		.tv_sec = 0,
109 		.tv_nsec = hrtimer_resolution,
110 	};
111 
112 	switch (which_clock) {
113 	case CLOCK_REALTIME:
114 	case CLOCK_MONOTONIC:
115 	case CLOCK_BOOTTIME:
116 		if (put_timespec64(&rtn_tp, tp))
117 			return -EFAULT;
118 		return 0;
119 	default:
120 		return -EINVAL;
121 	}
122 }
123 
124 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
125 		const struct __kernel_timespec __user *, rqtp,
126 		struct __kernel_timespec __user *, rmtp)
127 {
128 	struct timespec64 t;
129 
130 	switch (which_clock) {
131 	case CLOCK_REALTIME:
132 	case CLOCK_MONOTONIC:
133 	case CLOCK_BOOTTIME:
134 		break;
135 	default:
136 		return -EINVAL;
137 	}
138 
139 	if (get_timespec64(&t, rqtp))
140 		return -EFAULT;
141 	if (!timespec64_valid(&t))
142 		return -EINVAL;
143 	if (flags & TIMER_ABSTIME)
144 		rmtp = NULL;
145 	current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
146 	current->restart_block.nanosleep.rmtp = rmtp;
147 	return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
148 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
149 				 which_clock);
150 }
151 
152 #ifdef CONFIG_COMPAT
153 COMPAT_SYS_NI(timer_create);
154 COMPAT_SYS_NI(getitimer);
155 COMPAT_SYS_NI(setitimer);
156 #endif
157 
158 #ifdef CONFIG_COMPAT_32BIT_TIME
159 SYS_NI(timer_settime32);
160 SYS_NI(timer_gettime32);
161 
162 SYSCALL_DEFINE2(clock_settime32, const clockid_t, which_clock,
163 		struct old_timespec32 __user *, tp)
164 {
165 	struct timespec64 new_tp;
166 
167 	if (which_clock != CLOCK_REALTIME)
168 		return -EINVAL;
169 	if (get_old_timespec32(&new_tp, tp))
170 		return -EFAULT;
171 
172 	return do_sys_settimeofday64(&new_tp, NULL);
173 }
174 
175 SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
176 		struct old_timespec32 __user *, tp)
177 {
178 	int ret;
179 	struct timespec64 kernel_tp;
180 
181 	ret = do_clock_gettime(which_clock, &kernel_tp);
182 	if (ret)
183 		return ret;
184 
185 	if (put_old_timespec32(&kernel_tp, tp))
186 		return -EFAULT;
187 	return 0;
188 }
189 
190 SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
191 		struct old_timespec32 __user *, tp)
192 {
193 	struct timespec64 rtn_tp = {
194 		.tv_sec = 0,
195 		.tv_nsec = hrtimer_resolution,
196 	};
197 
198 	switch (which_clock) {
199 	case CLOCK_REALTIME:
200 	case CLOCK_MONOTONIC:
201 	case CLOCK_BOOTTIME:
202 		if (put_old_timespec32(&rtn_tp, tp))
203 			return -EFAULT;
204 		return 0;
205 	default:
206 		return -EINVAL;
207 	}
208 }
209 
210 SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
211 		struct old_timespec32 __user *, rqtp,
212 		struct old_timespec32 __user *, rmtp)
213 {
214 	struct timespec64 t;
215 
216 	switch (which_clock) {
217 	case CLOCK_REALTIME:
218 	case CLOCK_MONOTONIC:
219 	case CLOCK_BOOTTIME:
220 		break;
221 	default:
222 		return -EINVAL;
223 	}
224 
225 	if (get_old_timespec32(&t, rqtp))
226 		return -EFAULT;
227 	if (!timespec64_valid(&t))
228 		return -EINVAL;
229 	if (flags & TIMER_ABSTIME)
230 		rmtp = NULL;
231 	current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
232 	current->restart_block.nanosleep.compat_rmtp = rmtp;
233 	return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
234 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
235 				 which_clock);
236 }
237 #endif
238