xref: /openbmc/linux/kernel/time/posix-stubs.c (revision 5efb685b)
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.fn = do_no_restart_syscall;
151 	current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
152 	current->restart_block.nanosleep.rmtp = rmtp;
153 	texp = timespec64_to_ktime(t);
154 	if (flags & TIMER_ABSTIME)
155 		texp = timens_ktime_to_host(which_clock, texp);
156 	return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
157 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
158 				 which_clock);
159 }
160 
161 #ifdef CONFIG_COMPAT
162 COMPAT_SYS_NI(timer_create);
163 #endif
164 
165 #if defined(CONFIG_COMPAT) || defined(CONFIG_ALPHA)
166 COMPAT_SYS_NI(getitimer);
167 COMPAT_SYS_NI(setitimer);
168 #endif
169 
170 #ifdef CONFIG_COMPAT_32BIT_TIME
171 SYS_NI(timer_settime32);
172 SYS_NI(timer_gettime32);
173 
174 SYSCALL_DEFINE2(clock_settime32, const clockid_t, which_clock,
175 		struct old_timespec32 __user *, tp)
176 {
177 	struct timespec64 new_tp;
178 
179 	if (which_clock != CLOCK_REALTIME)
180 		return -EINVAL;
181 	if (get_old_timespec32(&new_tp, tp))
182 		return -EFAULT;
183 
184 	return do_sys_settimeofday64(&new_tp, NULL);
185 }
186 
187 SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
188 		struct old_timespec32 __user *, tp)
189 {
190 	int ret;
191 	struct timespec64 kernel_tp;
192 
193 	ret = do_clock_gettime(which_clock, &kernel_tp);
194 	if (ret)
195 		return ret;
196 
197 	if (put_old_timespec32(&kernel_tp, tp))
198 		return -EFAULT;
199 	return 0;
200 }
201 
202 SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
203 		struct old_timespec32 __user *, tp)
204 {
205 	struct timespec64 rtn_tp = {
206 		.tv_sec = 0,
207 		.tv_nsec = hrtimer_resolution,
208 	};
209 
210 	switch (which_clock) {
211 	case CLOCK_REALTIME:
212 	case CLOCK_MONOTONIC:
213 	case CLOCK_BOOTTIME:
214 		if (put_old_timespec32(&rtn_tp, tp))
215 			return -EFAULT;
216 		return 0;
217 	default:
218 		return -EINVAL;
219 	}
220 }
221 
222 SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
223 		struct old_timespec32 __user *, rqtp,
224 		struct old_timespec32 __user *, rmtp)
225 {
226 	struct timespec64 t;
227 	ktime_t texp;
228 
229 	switch (which_clock) {
230 	case CLOCK_REALTIME:
231 	case CLOCK_MONOTONIC:
232 	case CLOCK_BOOTTIME:
233 		break;
234 	default:
235 		return -EINVAL;
236 	}
237 
238 	if (get_old_timespec32(&t, rqtp))
239 		return -EFAULT;
240 	if (!timespec64_valid(&t))
241 		return -EINVAL;
242 	if (flags & TIMER_ABSTIME)
243 		rmtp = NULL;
244 	current->restart_block.fn = do_no_restart_syscall;
245 	current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
246 	current->restart_block.nanosleep.compat_rmtp = rmtp;
247 	texp = timespec64_to_ktime(t);
248 	if (flags & TIMER_ABSTIME)
249 		texp = timens_ktime_to_host(which_clock, texp);
250 	return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
251 				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
252 				 which_clock);
253 }
254 #endif
255