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	This read_persistent_clock() implementation is the only remaining caller of set_normalized_timespec(). Using read_persistent_clock64() and set_normalized_timespec64() instead lets us remove the deprecated interface in the future and helps make 32-bit arch/um get closer to working beyond 2038. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Richard Weinberger <richard@nod.at>
		
			
				
	
	
		
			136 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			136 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
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 * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
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 * Copyright (C) 2012-2014 Cisco Systems
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 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
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 * Licensed under the GPL
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 */
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#include <linux/clockchips.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/jiffies.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#include <linux/spinlock.h>
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#include <linux/threads.h>
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#include <asm/irq.h>
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#include <asm/param.h>
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#include <kern_util.h>
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#include <os.h>
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#include <timer-internal.h>
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void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
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{
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	unsigned long flags;
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	local_irq_save(flags);
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	do_IRQ(TIMER_IRQ, regs);
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	local_irq_restore(flags);
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}
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static int itimer_shutdown(struct clock_event_device *evt)
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{
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	os_timer_disable();
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	return 0;
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}
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static int itimer_set_periodic(struct clock_event_device *evt)
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{
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	os_timer_set_interval(NULL, NULL);
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	return 0;
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}
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static int itimer_next_event(unsigned long delta,
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			     struct clock_event_device *evt)
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{
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	return os_timer_one_shot(delta);
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}
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static int itimer_one_shot(struct clock_event_device *evt)
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{
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	os_timer_one_shot(1);
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	return 0;
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}
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static struct clock_event_device timer_clockevent = {
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	.name			= "posix-timer",
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	.rating			= 250,
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	.cpumask		= cpu_all_mask,
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	.features		= CLOCK_EVT_FEAT_PERIODIC |
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				  CLOCK_EVT_FEAT_ONESHOT,
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	.set_state_shutdown	= itimer_shutdown,
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	.set_state_periodic	= itimer_set_periodic,
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	.set_state_oneshot	= itimer_one_shot,
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	.set_next_event		= itimer_next_event,
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	.shift			= 0,
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	.max_delta_ns		= 0xffffffff,
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	.max_delta_ticks	= 0xffffffff,
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	.min_delta_ns		= TIMER_MIN_DELTA,
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	.min_delta_ticks	= TIMER_MIN_DELTA, // microsecond resolution should be enough for anyone, same as 640K RAM
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	.irq			= 0,
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	.mult			= 1,
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};
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static irqreturn_t um_timer(int irq, void *dev)
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{
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	if (get_current()->mm != NULL)
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	{
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        /* userspace - relay signal, results in correct userspace timers */
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		os_alarm_process(get_current()->mm->context.id.u.pid);
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	}
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	(*timer_clockevent.event_handler)(&timer_clockevent);
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	return IRQ_HANDLED;
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}
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static u64 timer_read(struct clocksource *cs)
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{
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	return os_nsecs() / TIMER_MULTIPLIER;
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}
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static struct clocksource timer_clocksource = {
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	.name		= "timer",
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	.rating		= 300,
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	.read		= timer_read,
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	.mask		= CLOCKSOURCE_MASK(64),
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	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static void __init um_timer_setup(void)
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{
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	int err;
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	err = request_irq(TIMER_IRQ, um_timer, IRQF_TIMER, "hr timer", NULL);
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	if (err != 0)
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		printk(KERN_ERR "register_timer : request_irq failed - "
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		       "errno = %d\n", -err);
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	err = os_timer_create(NULL);
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	if (err != 0) {
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		printk(KERN_ERR "creation of timer failed - errno = %d\n", -err);
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		return;
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	}
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	err = clocksource_register_hz(&timer_clocksource, NSEC_PER_SEC/TIMER_MULTIPLIER);
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	if (err) {
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		printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
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		return;
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	}
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	clockevents_register_device(&timer_clockevent);
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}
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void read_persistent_clock64(struct timespec64 *ts)
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{
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	long long nsecs = os_persistent_clock_emulation();
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	set_normalized_timespec64(ts, nsecs / NSEC_PER_SEC,
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				  nsecs % NSEC_PER_SEC);
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}
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void __init time_init(void)
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{
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	timer_set_signal_handler();
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	late_time_init = um_timer_setup;
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}
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