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

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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: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201209060932.212364-4-jianyong.wu@arm.com
This commit is contained in:
Jianyong Wu 2020-12-09 14:09:26 +08:00 committed by Marc Zyngier
parent 923961a7ff
commit a8cf291bda
4 changed files with 139 additions and 62 deletions
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1
drivers/ptp/Makefile
View File

@ -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

84
drivers/ptp/ptp_kvm.c → drivers/ptp/ptp_kvm_common.c
View File

@ -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);
spin_unlock(&kvm_ptp_lock);
preempt_enable_notrace();
return -EOPNOTSUPP;
}
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));
ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs);
if (ret) {
spin_unlock(&kvm_ptp_lock);
preempt_enable_notrace();
return ret;
}
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;

97
drivers/ptp/ptp_kvm_x86.c Normal file
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@ -0,0 +1,97 @@
// 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;
}

19
include/linux/ptp_kvm.h Normal file
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@ -0,0 +1,19 @@
/* 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_ */