Commit a8cf291b authored by Jianyong Wu's avatar Jianyong Wu Committed by Marc Zyngier
Browse files

ptp: Reorganize ptp_kvm.c to make it arch-independent 



Currently, the ptp_kvm module contains a lot of x86-specific code.
Let's move this code into a new arch-specific file in the same directory,
and rename the arch-independent file to ptp_kvm_common.c.

Acked-by: default avatarRichard Cochran <richardcochran@gmail.com>
Reviewed-by: default avatarAndre Przywara <andre.przywara@arm.com>
Signed-off-by: default avatarJianyong Wu <jianyong.wu@arm.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201209060932.212364-4-jianyong.wu@arm.com
parent 923961a7

drivers/ptp/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#



ptp-y					:= ptp_clock.o ptp_chardev.o ptp_sysfs.o

ptp_kvm-$(CONFIG_X86)			:= ptp_kvm_x86.o ptp_kvm_common.o

obj-$(CONFIG_PTP_1588_CLOCK)		+= ptp.o

obj-$(CONFIG_PTP_1588_CLOCK_DTE)	+= ptp_dte.o

obj-$(CONFIG_PTP_1588_CLOCK_INES)	+= ptp_ines.o

drivers/ptp/ptp_kvm.c→drivers/ptp/ptp_kvm_common.c

+22 −62
Original line number Diff line number Diff line
@@ -8,11 +8,11 @@ 
#include <linux/err.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/slab.h>

#include <linux/module.h>

#include <linux/ptp_kvm.h>

#include <uapi/linux/kvm_para.h>

#include <asm/kvm_para.h>

#include <asm/pvclock.h>

#include <asm/kvmclock.h>

#include <uapi/asm/kvm_para.h>



#include <linux/ptp_clock_kernel.h>
@@ -24,56 +24,29 @@ struct kvm_ptp_clock { 


static DEFINE_SPINLOCK(kvm_ptp_lock);



static struct pvclock_vsyscall_time_info *hv_clock;



static struct kvm_clock_pairing clock_pair;

static phys_addr_t clock_pair_gpa;



static int ptp_kvm_get_time_fn(ktime_t *device_time,

			       struct system_counterval_t *system_counter,

			       void *ctx)

{

	unsigned long ret;

	long ret;

	u64 cycle;

	struct timespec64 tspec;

	unsigned version;

	int cpu;

	struct pvclock_vcpu_time_info *src;

	struct clocksource *cs;



	spin_lock(&kvm_ptp_lock);



	preempt_disable_notrace();

	cpu = smp_processor_id();

	src = &hv_clock[cpu].pvti;



	do {

		/*

		 * We are using a TSC value read in the hosts

		 * kvm_hc_clock_pairing handling.

		 * So any changes to tsc_to_system_mul

		 * and tsc_shift or any other pvclock

		 * data invalidate that measurement.

		 */

		version = pvclock_read_begin(src);



		ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,

				     clock_pair_gpa,

				     KVM_CLOCK_PAIRING_WALLCLOCK);

		if (ret != 0) {

			pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);

	ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs);

	if (ret) {

		spin_unlock(&kvm_ptp_lock);

		preempt_enable_notrace();

			return -EOPNOTSUPP;

		return ret;

	}



		tspec.tv_sec = clock_pair.sec;

		tspec.tv_nsec = clock_pair.nsec;

		ret = __pvclock_read_cycles(src, clock_pair.tsc);

	} while (pvclock_read_retry(src, version));



	preempt_enable_notrace();



	system_counter->cycles = ret;

	system_counter->cs = &kvm_clock;

	system_counter->cycles = cycle;

	system_counter->cs = cs;



	*device_time = timespec64_to_ktime(tspec);
@@ -111,22 +84,17 @@ static int ptp_kvm_settime(struct ptp_clock_info *ptp, 


static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)

{

	unsigned long ret;

	long ret;

	struct timespec64 tspec;



	spin_lock(&kvm_ptp_lock);



	ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,

			     clock_pair_gpa,

			     KVM_CLOCK_PAIRING_WALLCLOCK);

	if (ret != 0) {

		pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);

	ret = kvm_arch_ptp_get_clock(&tspec);

	if (ret) {

		spin_unlock(&kvm_ptp_lock);

		return -EOPNOTSUPP;

		return ret;

	}



	tspec.tv_sec = clock_pair.sec;

	tspec.tv_nsec = clock_pair.nsec;

	spin_unlock(&kvm_ptp_lock);



	memcpy(ts, &tspec, sizeof(struct timespec64));
@@ -168,19 +136,11 @@ static int __init ptp_kvm_init(void) 
{

	long ret;



	if (!kvm_para_available())

		return -ENODEV;



	clock_pair_gpa = slow_virt_to_phys(&clock_pair);

	hv_clock = pvclock_get_pvti_cpu0_va();



	if (!hv_clock)

		return -ENODEV;



	ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,

			KVM_CLOCK_PAIRING_WALLCLOCK);

	if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)

		return -ENODEV;

	ret = kvm_arch_ptp_init();

	if (ret) {

		pr_err("fail to initialize ptp_kvm");

		return ret;

	}



	kvm_ptp_clock.caps = ptp_kvm_caps;

drivers/ptp/ptp_kvm_x86.c

0 → 100644
+97 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * Virtual PTP 1588 clock for use with KVM guests

 *

 * Copyright (C) 2017 Red Hat Inc.

 */



#include <linux/device.h>

#include <linux/kernel.h>

#include <asm/pvclock.h>

#include <asm/kvmclock.h>

#include <linux/module.h>

#include <uapi/asm/kvm_para.h>

#include <uapi/linux/kvm_para.h>

#include <linux/ptp_clock_kernel.h>

#include <linux/ptp_kvm.h>



struct pvclock_vsyscall_time_info *hv_clock;



static phys_addr_t clock_pair_gpa;

static struct kvm_clock_pairing clock_pair;



int kvm_arch_ptp_init(void)

{

	long ret;



	if (!kvm_para_available())

		return -ENODEV;



	clock_pair_gpa = slow_virt_to_phys(&clock_pair);

	hv_clock = pvclock_get_pvti_cpu0_va();

	if (!hv_clock)

		return -ENODEV;



	ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,

			     KVM_CLOCK_PAIRING_WALLCLOCK);

	if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)

		return -ENODEV;



	return 0;

}



int kvm_arch_ptp_get_clock(struct timespec64 *ts)

{

	long ret;



	ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,

			     clock_pair_gpa,

			     KVM_CLOCK_PAIRING_WALLCLOCK);

	if (ret != 0) {

		pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);

		return -EOPNOTSUPP;

	}



	ts->tv_sec = clock_pair.sec;

	ts->tv_nsec = clock_pair.nsec;



	return 0;

}



int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,

			      struct clocksource **cs)

{

	struct pvclock_vcpu_time_info *src;

	unsigned int version;

	long ret;

	int cpu;



	cpu = smp_processor_id();

	src = &hv_clock[cpu].pvti;



	do {

		/*

		 * We are using a TSC value read in the hosts

		 * kvm_hc_clock_pairing handling.

		 * So any changes to tsc_to_system_mul

		 * and tsc_shift or any other pvclock

		 * data invalidate that measurement.

		 */

		version = pvclock_read_begin(src);



		ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,

				     clock_pair_gpa,

				     KVM_CLOCK_PAIRING_WALLCLOCK);

		if (ret != 0) {

			pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);

			return -EOPNOTSUPP;

		}

		tspec->tv_sec = clock_pair.sec;

		tspec->tv_nsec = clock_pair.nsec;

		*cycle = __pvclock_read_cycles(src, clock_pair.tsc);

	} while (pvclock_read_retry(src, version));



	*cs = &kvm_clock;



	return 0;

}

include/linux/ptp_kvm.h

0 → 100644
+19 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-or-later */

/*

 * Virtual PTP 1588 clock for use with KVM guests

 *

 * Copyright (C) 2017 Red Hat Inc.

 */



#ifndef _PTP_KVM_H_

#define _PTP_KVM_H_



struct timespec64;

struct clocksource;



int kvm_arch_ptp_init(void);

int kvm_arch_ptp_get_clock(struct timespec64 *ts);

int kvm_arch_ptp_get_crosststamp(u64 *cycle,

		struct timespec64 *tspec, struct clocksource **cs);



#endif /* _PTP_KVM_H_ */