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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic userspace implementations of gettimeofday() and similar.
  4 */
  5#include <vdso/datapage.h>
  6#include <vdso/helpers.h>
  7
  8#ifndef vdso_calc_ns
  9
 10#ifdef VDSO_DELTA_NOMASK
 11# define VDSO_DELTA_MASK(vd)	ULLONG_MAX
 12#else
 13# define VDSO_DELTA_MASK(vd)	(vd->mask)
 14#endif
 15
 16#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT
 17static __always_inline bool vdso_delta_ok(const struct vdso_data *vd, u64 delta)
 18{
 19	return delta < vd->max_cycles;
 20}
 21#else
 22static __always_inline bool vdso_delta_ok(const struct vdso_data *vd, u64 delta)
 23{
 24	return true;
 25}
 26#endif
 27
 28#ifndef vdso_shift_ns
 29static __always_inline u64 vdso_shift_ns(u64 ns, u32 shift)
 30{
 31	return ns >> shift;
 32}
 33#endif
 34
 35/*
 36 * Default implementation which works for all sane clocksources. That
 37 * obviously excludes x86/TSC.
 38 */
 39static __always_inline u64 vdso_calc_ns(const struct vdso_data *vd, u64 cycles, u64 base)
 40{
 41	u64 delta = (cycles - vd->cycle_last) & VDSO_DELTA_MASK(vd);
 42
 43	if (likely(vdso_delta_ok(vd, delta)))
 44		return vdso_shift_ns((delta * vd->mult) + base, vd->shift);
 45
 46	return mul_u64_u32_add_u64_shr(delta, vd->mult, base, vd->shift);
 47}
 48#endif /* vdso_calc_ns */
 49
 50#ifndef __arch_vdso_hres_capable
 51static inline bool __arch_vdso_hres_capable(void)
 52{
 53	return true;
 54}
 55#endif
 56
 57#ifndef vdso_clocksource_ok
 58static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
 59{
 60	return vd->clock_mode != VDSO_CLOCKMODE_NONE;
 61}
 62#endif
 63
 64#ifndef vdso_cycles_ok
 65static inline bool vdso_cycles_ok(u64 cycles)
 66{
 67	return true;
 68}
 69#endif
 70
 71#ifdef CONFIG_TIME_NS
 72static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
 73					  struct __kernel_timespec *ts)
 74{
 
 75	const struct timens_offset *offs = &vdns->offset[clk];
 76	const struct vdso_timestamp *vdso_ts;
 77	const struct vdso_data *vd;
 78	u64 cycles, ns;
 79	u32 seq;
 80	s64 sec;
 81
 82	vd = vdns - (clk == CLOCK_MONOTONIC_RAW ? CS_RAW : CS_HRES_COARSE);
 83	vd = __arch_get_timens_vdso_data(vd);
 84	if (clk != CLOCK_MONOTONIC_RAW)
 85		vd = &vd[CS_HRES_COARSE];
 86	else
 87		vd = &vd[CS_RAW];
 88	vdso_ts = &vd->basetime[clk];
 89
 90	do {
 91		seq = vdso_read_begin(vd);
 92
 93		if (unlikely(!vdso_clocksource_ok(vd)))
 94			return -1;
 95
 96		cycles = __arch_get_hw_counter(vd->clock_mode, vd);
 97		if (unlikely(!vdso_cycles_ok(cycles)))
 98			return -1;
 99		ns = vdso_calc_ns(vd, cycles, vdso_ts->nsec);
 
 
 
100		sec = vdso_ts->sec;
101	} while (unlikely(vdso_read_retry(vd, seq)));
102
103	/* Add the namespace offset */
104	sec += offs->sec;
105	ns += offs->nsec;
106
107	/*
108	 * Do this outside the loop: a race inside the loop could result
109	 * in __iter_div_u64_rem() being extremely slow.
110	 */
111	ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
112	ts->tv_nsec = ns;
113
114	return 0;
115}
116#else
117static __always_inline
118const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
119{
120	return NULL;
121}
122
123static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
124					  struct __kernel_timespec *ts)
125{
126	return -EINVAL;
127}
128#endif
129
130static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk,
131				   struct __kernel_timespec *ts)
132{
133	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
134	u64 cycles, sec, ns;
135	u32 seq;
136
137	/* Allows to compile the high resolution parts out */
138	if (!__arch_vdso_hres_capable())
139		return -1;
140
141	do {
142		/*
143		 * Open coded function vdso_read_begin() to handle
144		 * VDSO_CLOCKMODE_TIMENS. Time namespace enabled tasks have a
145		 * special VVAR page installed which has vd->seq set to 1 and
146		 * vd->clock_mode set to VDSO_CLOCKMODE_TIMENS. For non time
147		 * namespace affected tasks this does not affect performance
148		 * because if vd->seq is odd, i.e. a concurrent update is in
149		 * progress the extra check for vd->clock_mode is just a few
150		 * extra instructions while spin waiting for vd->seq to become
151		 * even again.
152		 */
153		while (unlikely((seq = READ_ONCE(vd->seq)) & 1)) {
154			if (IS_ENABLED(CONFIG_TIME_NS) &&
155			    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
156				return do_hres_timens(vd, clk, ts);
157			cpu_relax();
158		}
159		smp_rmb();
160
161		if (unlikely(!vdso_clocksource_ok(vd)))
162			return -1;
163
164		cycles = __arch_get_hw_counter(vd->clock_mode, vd);
165		if (unlikely(!vdso_cycles_ok(cycles)))
166			return -1;
167		ns = vdso_calc_ns(vd, cycles, vdso_ts->nsec);
 
 
 
168		sec = vdso_ts->sec;
169	} while (unlikely(vdso_read_retry(vd, seq)));
170
171	/*
172	 * Do this outside the loop: a race inside the loop could result
173	 * in __iter_div_u64_rem() being extremely slow.
174	 */
175	ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
176	ts->tv_nsec = ns;
177
178	return 0;
179}
180
181#ifdef CONFIG_TIME_NS
182static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
183					    struct __kernel_timespec *ts)
184{
185	const struct vdso_data *vd = __arch_get_timens_vdso_data(vdns);
186	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
187	const struct timens_offset *offs = &vdns->offset[clk];
188	u64 nsec;
189	s64 sec;
190	s32 seq;
191
192	do {
193		seq = vdso_read_begin(vd);
194		sec = vdso_ts->sec;
195		nsec = vdso_ts->nsec;
196	} while (unlikely(vdso_read_retry(vd, seq)));
197
198	/* Add the namespace offset */
199	sec += offs->sec;
200	nsec += offs->nsec;
201
202	/*
203	 * Do this outside the loop: a race inside the loop could result
204	 * in __iter_div_u64_rem() being extremely slow.
205	 */
206	ts->tv_sec = sec + __iter_div_u64_rem(nsec, NSEC_PER_SEC, &nsec);
207	ts->tv_nsec = nsec;
208	return 0;
209}
210#else
211static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
212					    struct __kernel_timespec *ts)
213{
214	return -1;
215}
216#endif
217
218static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk,
219				     struct __kernel_timespec *ts)
220{
221	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
222	u32 seq;
223
224	do {
225		/*
226		 * Open coded function vdso_read_begin() to handle
227		 * VDSO_CLOCK_TIMENS. See comment in do_hres().
228		 */
229		while ((seq = READ_ONCE(vd->seq)) & 1) {
230			if (IS_ENABLED(CONFIG_TIME_NS) &&
231			    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
232				return do_coarse_timens(vd, clk, ts);
233			cpu_relax();
234		}
235		smp_rmb();
236
237		ts->tv_sec = vdso_ts->sec;
238		ts->tv_nsec = vdso_ts->nsec;
239	} while (unlikely(vdso_read_retry(vd, seq)));
240
241	return 0;
242}
243
244static __always_inline int
245__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock,
246			     struct __kernel_timespec *ts)
247{
248	u32 msk;
249
250	/* Check for negative values or invalid clocks */
251	if (unlikely((u32) clock >= MAX_CLOCKS))
252		return -1;
253
254	/*
255	 * Convert the clockid to a bitmask and use it to check which
256	 * clocks are handled in the VDSO directly.
257	 */
258	msk = 1U << clock;
259	if (likely(msk & VDSO_HRES))
260		vd = &vd[CS_HRES_COARSE];
261	else if (msk & VDSO_COARSE)
262		return do_coarse(&vd[CS_HRES_COARSE], clock, ts);
263	else if (msk & VDSO_RAW)
264		vd = &vd[CS_RAW];
265	else
266		return -1;
267
268	return do_hres(vd, clock, ts);
269}
270
271static __maybe_unused int
272__cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock,
273			   struct __kernel_timespec *ts)
274{
275	int ret = __cvdso_clock_gettime_common(vd, clock, ts);
276
277	if (unlikely(ret))
278		return clock_gettime_fallback(clock, ts);
279	return 0;
280}
281
282static __maybe_unused int
283__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
284{
285	return __cvdso_clock_gettime_data(__arch_get_vdso_data(), clock, ts);
286}
287
288#ifdef BUILD_VDSO32
289static __maybe_unused int
290__cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock,
291			     struct old_timespec32 *res)
292{
293	struct __kernel_timespec ts;
294	int ret;
295
296	ret = __cvdso_clock_gettime_common(vd, clock, &ts);
297
298	if (unlikely(ret))
299		return clock_gettime32_fallback(clock, res);
300
301	/* For ret == 0 */
302	res->tv_sec = ts.tv_sec;
303	res->tv_nsec = ts.tv_nsec;
304
305	return ret;
306}
307
308static __maybe_unused int
309__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
310{
311	return __cvdso_clock_gettime32_data(__arch_get_vdso_data(), clock, res);
312}
313#endif /* BUILD_VDSO32 */
314
315static __maybe_unused int
316__cvdso_gettimeofday_data(const struct vdso_data *vd,
317			  struct __kernel_old_timeval *tv, struct timezone *tz)
318{
319
320	if (likely(tv != NULL)) {
321		struct __kernel_timespec ts;
322
323		if (do_hres(&vd[CS_HRES_COARSE], CLOCK_REALTIME, &ts))
324			return gettimeofday_fallback(tv, tz);
325
326		tv->tv_sec = ts.tv_sec;
327		tv->tv_usec = (u32)ts.tv_nsec / NSEC_PER_USEC;
328	}
329
330	if (unlikely(tz != NULL)) {
331		if (IS_ENABLED(CONFIG_TIME_NS) &&
332		    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
333			vd = __arch_get_timens_vdso_data(vd);
334
335		tz->tz_minuteswest = vd[CS_HRES_COARSE].tz_minuteswest;
336		tz->tz_dsttime = vd[CS_HRES_COARSE].tz_dsttime;
337	}
338
339	return 0;
340}
341
342static __maybe_unused int
343__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
344{
345	return __cvdso_gettimeofday_data(__arch_get_vdso_data(), tv, tz);
346}
347
348#ifdef VDSO_HAS_TIME
349static __maybe_unused __kernel_old_time_t
350__cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time)
351{
352	__kernel_old_time_t t;
353
354	if (IS_ENABLED(CONFIG_TIME_NS) &&
355	    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
356		vd = __arch_get_timens_vdso_data(vd);
357
358	t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
359
360	if (time)
361		*time = t;
362
363	return t;
364}
365
366static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time)
367{
368	return __cvdso_time_data(__arch_get_vdso_data(), time);
369}
370#endif /* VDSO_HAS_TIME */
371
372#ifdef VDSO_HAS_CLOCK_GETRES
373static __maybe_unused
374int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
375				struct __kernel_timespec *res)
376{
377	u32 msk;
378	u64 ns;
379
380	/* Check for negative values or invalid clocks */
381	if (unlikely((u32) clock >= MAX_CLOCKS))
382		return -1;
383
384	if (IS_ENABLED(CONFIG_TIME_NS) &&
385	    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
386		vd = __arch_get_timens_vdso_data(vd);
387
388	/*
389	 * Convert the clockid to a bitmask and use it to check which
390	 * clocks are handled in the VDSO directly.
391	 */
392	msk = 1U << clock;
393	if (msk & (VDSO_HRES | VDSO_RAW)) {
394		/*
395		 * Preserves the behaviour of posix_get_hrtimer_res().
396		 */
397		ns = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
398	} else if (msk & VDSO_COARSE) {
399		/*
400		 * Preserves the behaviour of posix_get_coarse_res().
401		 */
402		ns = LOW_RES_NSEC;
403	} else {
404		return -1;
405	}
406
407	if (likely(res)) {
408		res->tv_sec = 0;
409		res->tv_nsec = ns;
410	}
411	return 0;
412}
413
414static __maybe_unused
415int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock,
416			      struct __kernel_timespec *res)
417{
418	int ret = __cvdso_clock_getres_common(vd, clock, res);
419
420	if (unlikely(ret))
421		return clock_getres_fallback(clock, res);
422	return 0;
423}
424
425static __maybe_unused
426int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
427{
428	return __cvdso_clock_getres_data(__arch_get_vdso_data(), clock, res);
429}
430
431#ifdef BUILD_VDSO32
432static __maybe_unused int
433__cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock,
434				 struct old_timespec32 *res)
435{
436	struct __kernel_timespec ts;
437	int ret;
438
439	ret = __cvdso_clock_getres_common(vd, clock, &ts);
440
441	if (unlikely(ret))
442		return clock_getres32_fallback(clock, res);
443
444	if (likely(res)) {
445		res->tv_sec = ts.tv_sec;
446		res->tv_nsec = ts.tv_nsec;
447	}
448	return ret;
449}
450
451static __maybe_unused int
452__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
453{
454	return __cvdso_clock_getres_time32_data(__arch_get_vdso_data(),
455						clock, res);
456}
457#endif /* BUILD_VDSO32 */
458#endif /* VDSO_HAS_CLOCK_GETRES */
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic userspace implementations of gettimeofday() and similar.
  4 */
  5#include <vdso/datapage.h>
  6#include <vdso/helpers.h>
  7
  8#ifndef vdso_calc_delta
  9/*
 10 * Default implementation which works for all sane clocksources. That
 11 * obviously excludes x86/TSC.
 12 */
 13static __always_inline
 14u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
 
 
 
 15{
 16	return ((cycles - last) & mask) * mult;
 
 
 
 
 
 17}
 18#endif
 19
 20#ifndef vdso_shift_ns
 21static __always_inline u64 vdso_shift_ns(u64 ns, u32 shift)
 22{
 23	return ns >> shift;
 24}
 25#endif
 26
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 27#ifndef __arch_vdso_hres_capable
 28static inline bool __arch_vdso_hres_capable(void)
 29{
 30	return true;
 31}
 32#endif
 33
 34#ifndef vdso_clocksource_ok
 35static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
 36{
 37	return vd->clock_mode != VDSO_CLOCKMODE_NONE;
 38}
 39#endif
 40
 41#ifndef vdso_cycles_ok
 42static inline bool vdso_cycles_ok(u64 cycles)
 43{
 44	return true;
 45}
 46#endif
 47
 48#ifdef CONFIG_TIME_NS
 49static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
 50			  struct __kernel_timespec *ts)
 51{
 52	const struct vdso_data *vd = __arch_get_timens_vdso_data();
 53	const struct timens_offset *offs = &vdns->offset[clk];
 54	const struct vdso_timestamp *vdso_ts;
 55	u64 cycles, last, ns;
 
 56	u32 seq;
 57	s64 sec;
 58
 
 
 59	if (clk != CLOCK_MONOTONIC_RAW)
 60		vd = &vd[CS_HRES_COARSE];
 61	else
 62		vd = &vd[CS_RAW];
 63	vdso_ts = &vd->basetime[clk];
 64
 65	do {
 66		seq = vdso_read_begin(vd);
 67
 68		if (unlikely(!vdso_clocksource_ok(vd)))
 69			return -1;
 70
 71		cycles = __arch_get_hw_counter(vd->clock_mode, vd);
 72		if (unlikely(!vdso_cycles_ok(cycles)))
 73			return -1;
 74		ns = vdso_ts->nsec;
 75		last = vd->cycle_last;
 76		ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
 77		ns = vdso_shift_ns(ns, vd->shift);
 78		sec = vdso_ts->sec;
 79	} while (unlikely(vdso_read_retry(vd, seq)));
 80
 81	/* Add the namespace offset */
 82	sec += offs->sec;
 83	ns += offs->nsec;
 84
 85	/*
 86	 * Do this outside the loop: a race inside the loop could result
 87	 * in __iter_div_u64_rem() being extremely slow.
 88	 */
 89	ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
 90	ts->tv_nsec = ns;
 91
 92	return 0;
 93}
 94#else
 95static __always_inline const struct vdso_data *__arch_get_timens_vdso_data(void)
 
 96{
 97	return NULL;
 98}
 99
100static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
101			  struct __kernel_timespec *ts)
102{
103	return -EINVAL;
104}
105#endif
106
107static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk,
108				   struct __kernel_timespec *ts)
109{
110	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
111	u64 cycles, last, sec, ns;
112	u32 seq;
113
114	/* Allows to compile the high resolution parts out */
115	if (!__arch_vdso_hres_capable())
116		return -1;
117
118	do {
119		/*
120		 * Open coded to handle VDSO_CLOCKMODE_TIMENS. Time namespace
121		 * enabled tasks have a special VVAR page installed which
122		 * has vd->seq set to 1 and vd->clock_mode set to
123		 * VDSO_CLOCKMODE_TIMENS. For non time namespace affected tasks
124		 * this does not affect performance because if vd->seq is
125		 * odd, i.e. a concurrent update is in progress the extra
126		 * check for vd->clock_mode is just a few extra
127		 * instructions while spin waiting for vd->seq to become
128		 * even again.
129		 */
130		while (unlikely((seq = READ_ONCE(vd->seq)) & 1)) {
131			if (IS_ENABLED(CONFIG_TIME_NS) &&
132			    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
133				return do_hres_timens(vd, clk, ts);
134			cpu_relax();
135		}
136		smp_rmb();
137
138		if (unlikely(!vdso_clocksource_ok(vd)))
139			return -1;
140
141		cycles = __arch_get_hw_counter(vd->clock_mode, vd);
142		if (unlikely(!vdso_cycles_ok(cycles)))
143			return -1;
144		ns = vdso_ts->nsec;
145		last = vd->cycle_last;
146		ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
147		ns = vdso_shift_ns(ns, vd->shift);
148		sec = vdso_ts->sec;
149	} while (unlikely(vdso_read_retry(vd, seq)));
150
151	/*
152	 * Do this outside the loop: a race inside the loop could result
153	 * in __iter_div_u64_rem() being extremely slow.
154	 */
155	ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
156	ts->tv_nsec = ns;
157
158	return 0;
159}
160
161#ifdef CONFIG_TIME_NS
162static int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
163			    struct __kernel_timespec *ts)
164{
165	const struct vdso_data *vd = __arch_get_timens_vdso_data();
166	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
167	const struct timens_offset *offs = &vdns->offset[clk];
168	u64 nsec;
169	s64 sec;
170	s32 seq;
171
172	do {
173		seq = vdso_read_begin(vd);
174		sec = vdso_ts->sec;
175		nsec = vdso_ts->nsec;
176	} while (unlikely(vdso_read_retry(vd, seq)));
177
178	/* Add the namespace offset */
179	sec += offs->sec;
180	nsec += offs->nsec;
181
182	/*
183	 * Do this outside the loop: a race inside the loop could result
184	 * in __iter_div_u64_rem() being extremely slow.
185	 */
186	ts->tv_sec = sec + __iter_div_u64_rem(nsec, NSEC_PER_SEC, &nsec);
187	ts->tv_nsec = nsec;
188	return 0;
189}
190#else
191static int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
192			    struct __kernel_timespec *ts)
193{
194	return -1;
195}
196#endif
197
198static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk,
199				     struct __kernel_timespec *ts)
200{
201	const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
202	u32 seq;
203
204	do {
205		/*
206		 * Open coded to handle VDSO_CLOCK_TIMENS. See comment in
207		 * do_hres().
208		 */
209		while ((seq = READ_ONCE(vd->seq)) & 1) {
210			if (IS_ENABLED(CONFIG_TIME_NS) &&
211			    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
212				return do_coarse_timens(vd, clk, ts);
213			cpu_relax();
214		}
215		smp_rmb();
216
217		ts->tv_sec = vdso_ts->sec;
218		ts->tv_nsec = vdso_ts->nsec;
219	} while (unlikely(vdso_read_retry(vd, seq)));
220
221	return 0;
222}
223
224static __always_inline int
225__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock,
226			     struct __kernel_timespec *ts)
227{
228	u32 msk;
229
230	/* Check for negative values or invalid clocks */
231	if (unlikely((u32) clock >= MAX_CLOCKS))
232		return -1;
233
234	/*
235	 * Convert the clockid to a bitmask and use it to check which
236	 * clocks are handled in the VDSO directly.
237	 */
238	msk = 1U << clock;
239	if (likely(msk & VDSO_HRES))
240		vd = &vd[CS_HRES_COARSE];
241	else if (msk & VDSO_COARSE)
242		return do_coarse(&vd[CS_HRES_COARSE], clock, ts);
243	else if (msk & VDSO_RAW)
244		vd = &vd[CS_RAW];
245	else
246		return -1;
247
248	return do_hres(vd, clock, ts);
249}
250
251static __maybe_unused int
252__cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock,
253			   struct __kernel_timespec *ts)
254{
255	int ret = __cvdso_clock_gettime_common(vd, clock, ts);
256
257	if (unlikely(ret))
258		return clock_gettime_fallback(clock, ts);
259	return 0;
260}
261
262static __maybe_unused int
263__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
264{
265	return __cvdso_clock_gettime_data(__arch_get_vdso_data(), clock, ts);
266}
267
268#ifdef BUILD_VDSO32
269static __maybe_unused int
270__cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock,
271			     struct old_timespec32 *res)
272{
273	struct __kernel_timespec ts;
274	int ret;
275
276	ret = __cvdso_clock_gettime_common(vd, clock, &ts);
277
278	if (unlikely(ret))
279		return clock_gettime32_fallback(clock, res);
280
281	/* For ret == 0 */
282	res->tv_sec = ts.tv_sec;
283	res->tv_nsec = ts.tv_nsec;
284
285	return ret;
286}
287
288static __maybe_unused int
289__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
290{
291	return __cvdso_clock_gettime32_data(__arch_get_vdso_data(), clock, res);
292}
293#endif /* BUILD_VDSO32 */
294
295static __maybe_unused int
296__cvdso_gettimeofday_data(const struct vdso_data *vd,
297			  struct __kernel_old_timeval *tv, struct timezone *tz)
298{
299
300	if (likely(tv != NULL)) {
301		struct __kernel_timespec ts;
302
303		if (do_hres(&vd[CS_HRES_COARSE], CLOCK_REALTIME, &ts))
304			return gettimeofday_fallback(tv, tz);
305
306		tv->tv_sec = ts.tv_sec;
307		tv->tv_usec = (u32)ts.tv_nsec / NSEC_PER_USEC;
308	}
309
310	if (unlikely(tz != NULL)) {
311		if (IS_ENABLED(CONFIG_TIME_NS) &&
312		    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
313			vd = __arch_get_timens_vdso_data();
314
315		tz->tz_minuteswest = vd[CS_HRES_COARSE].tz_minuteswest;
316		tz->tz_dsttime = vd[CS_HRES_COARSE].tz_dsttime;
317	}
318
319	return 0;
320}
321
322static __maybe_unused int
323__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
324{
325	return __cvdso_gettimeofday_data(__arch_get_vdso_data(), tv, tz);
326}
327
328#ifdef VDSO_HAS_TIME
329static __maybe_unused __kernel_old_time_t
330__cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time)
331{
332	__kernel_old_time_t t;
333
334	if (IS_ENABLED(CONFIG_TIME_NS) &&
335	    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
336		vd = __arch_get_timens_vdso_data();
337
338	t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
339
340	if (time)
341		*time = t;
342
343	return t;
344}
345
346static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time)
347{
348	return __cvdso_time_data(__arch_get_vdso_data(), time);
349}
350#endif /* VDSO_HAS_TIME */
351
352#ifdef VDSO_HAS_CLOCK_GETRES
353static __maybe_unused
354int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
355				struct __kernel_timespec *res)
356{
357	u32 msk;
358	u64 ns;
359
360	/* Check for negative values or invalid clocks */
361	if (unlikely((u32) clock >= MAX_CLOCKS))
362		return -1;
363
364	if (IS_ENABLED(CONFIG_TIME_NS) &&
365	    vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
366		vd = __arch_get_timens_vdso_data();
367
368	/*
369	 * Convert the clockid to a bitmask and use it to check which
370	 * clocks are handled in the VDSO directly.
371	 */
372	msk = 1U << clock;
373	if (msk & (VDSO_HRES | VDSO_RAW)) {
374		/*
375		 * Preserves the behaviour of posix_get_hrtimer_res().
376		 */
377		ns = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
378	} else if (msk & VDSO_COARSE) {
379		/*
380		 * Preserves the behaviour of posix_get_coarse_res().
381		 */
382		ns = LOW_RES_NSEC;
383	} else {
384		return -1;
385	}
386
387	if (likely(res)) {
388		res->tv_sec = 0;
389		res->tv_nsec = ns;
390	}
391	return 0;
392}
393
394static __maybe_unused
395int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock,
396			      struct __kernel_timespec *res)
397{
398	int ret = __cvdso_clock_getres_common(vd, clock, res);
399
400	if (unlikely(ret))
401		return clock_getres_fallback(clock, res);
402	return 0;
403}
404
405static __maybe_unused
406int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
407{
408	return __cvdso_clock_getres_data(__arch_get_vdso_data(), clock, res);
409}
410
411#ifdef BUILD_VDSO32
412static __maybe_unused int
413__cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock,
414				 struct old_timespec32 *res)
415{
416	struct __kernel_timespec ts;
417	int ret;
418
419	ret = __cvdso_clock_getres_common(vd, clock, &ts);
420
421	if (unlikely(ret))
422		return clock_getres32_fallback(clock, res);
423
424	if (likely(res)) {
425		res->tv_sec = ts.tv_sec;
426		res->tv_nsec = ts.tv_nsec;
427	}
428	return ret;
429}
430
431static __maybe_unused int
432__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
433{
434	return __cvdso_clock_getres_time32_data(__arch_get_vdso_data(),
435						clock, res);
436}
437#endif /* BUILD_VDSO32 */
438#endif /* VDSO_HAS_CLOCK_GETRES */