Commit 775f71eb authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

timekeeping: Make do_adjtimex() reusable 



Split out the actual functionality of adjtimex() and make do_adjtimex() a
wrapper which feeds the core timekeeper into it and handles the result
including audit at the call site.

This allows to reuse the actual functionality for auxiliary clocks.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarJohn Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250625183758.187322876@linutronix.de
parent 2c8aea59

kernel/time/timekeeping.c

+56 −46
Original line number Diff line number Diff line
@@ -2585,17 +2585,18 @@ unsigned long random_get_entropy_fallback(void) 
}

EXPORT_SYMBOL_GPL(random_get_entropy_fallback);



/**

 * do_adjtimex() - Accessor function to NTP __do_adjtimex function

 * @txc:	Pointer to kernel_timex structure containing NTP parameters

 */

int do_adjtimex(struct __kernel_timex *txc)

{

	struct tk_data *tkd = &tk_core;

	struct timespec64 delta, ts;

struct adjtimex_result {

	struct audit_ntp_data	ad;

	bool offset_set = false;

	bool clock_set = false;

	struct timespec64	delta;

	bool			clock_set;

};



static int __do_adjtimex(struct tk_data *tkd, struct __kernel_timex *txc,

			 struct adjtimex_result *result)

{

	struct timekeeper *tks = &tkd->shadow_timekeeper;

	struct timespec64 ts;

	s32 orig_tai, tai;

	int ret;



	/* Validate the data before disabling interrupts */
@@ -2604,56 +2605,65 @@ int do_adjtimex(struct __kernel_timex *txc) 
		return ret;

	add_device_randomness(txc, sizeof(*txc));



	audit_ntp_init(&ad);



	ktime_get_real_ts64(&ts);

	add_device_randomness(&ts, sizeof(ts));



	scoped_guard (raw_spinlock_irqsave, &tkd->lock) {

		struct timekeeper *tks = &tkd->shadow_timekeeper;

		s32 orig_tai, tai;

	guard(raw_spinlock_irqsave)(&tkd->lock);



	if (!tks->clock_valid)

		return -ENODEV;



	if (txc->modes & ADJ_SETOFFSET) {

			delta.tv_sec  = txc->time.tv_sec;

			delta.tv_nsec = txc->time.tv_usec;

		result->delta.tv_sec  = txc->time.tv_sec;

		result->delta.tv_nsec = txc->time.tv_usec;

		if (!(txc->modes & ADJ_NANO))

				delta.tv_nsec *= 1000;

			ret = __timekeeping_inject_offset(tkd, &delta);

			result->delta.tv_nsec *= 1000;

		ret = __timekeeping_inject_offset(tkd, &result->delta);

		if (ret)

			return ret;



			offset_set = delta.tv_sec != 0;

			clock_set = true;

		result->clock_set = true;

	}



	orig_tai = tai = tks->tai_offset;

		ret = ntp_adjtimex(tks->id, txc, &ts, &tai, &ad);

	ret = ntp_adjtimex(tks->id, txc, &ts, &tai, &result->ad);



	if (tai != orig_tai) {

		__timekeeping_set_tai_offset(tks, tai);

		timekeeping_update_from_shadow(tkd, TK_CLOCK_WAS_SET);

			clock_set = true;

		result->clock_set = true;

	} else {

		tk_update_leap_state_all(&tk_core);

	}



	/* Update the multiplier immediately if frequency was set directly */

	if (txc->modes & (ADJ_FREQUENCY | ADJ_TICK))

			clock_set |= __timekeeping_advance(tkd, TK_ADV_FREQ);

		result->clock_set |= __timekeeping_advance(tkd, TK_ADV_FREQ);



	return ret;

}



/**

 * do_adjtimex() - Accessor function to NTP __do_adjtimex function

 * @txc:	Pointer to kernel_timex structure containing NTP parameters

 */

int do_adjtimex(struct __kernel_timex *txc)

{

	struct adjtimex_result result = { };

	int ret;



	ret = __do_adjtimex(&tk_core, txc, &result);

	if (ret < 0)

		return ret;



	if (txc->modes & ADJ_SETOFFSET)

		audit_tk_injoffset(delta);

		audit_tk_injoffset(result.delta);



	audit_ntp_log(&ad);

	audit_ntp_log(&result.ad);



	if (clock_set)

	if (result.clock_set)

		clock_was_set(CLOCK_SET_WALL);



	ntp_notify_cmos_timer(offset_set);

	ntp_notify_cmos_timer(result.delta.tv_sec != 0);



	return ret;

}