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linux
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: 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
authored by
Jianyong Wu
and committed by
Marc Zyngier
a8cf291b
923961a7
+139
-62
+1
drivers/ptp/Makefile
+1
drivers/ptp/Makefile
+22
-62
drivers/ptp/ptp_kvm.c
drivers/ptp/ptp_kvm_common.c
+22
-62
drivers/ptp/ptp_kvm.c
drivers/ptp/ptp_kvm_common.c
···
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8
#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/ptp_kvm.h>
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#include <uapi/linux/kvm_para.h>
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#include <asm/kvm_para.h>
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-
#include <asm/pvclock.h>
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#include <asm/kvmclock.h>
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#include <uapi/asm/kvm_para.h>
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#include <linux/ptp_clock_kernel.h>
···
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static DEFINE_SPINLOCK(kvm_ptp_lock);
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-
static struct pvclock_vsyscall_time_info *hv_clock;
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-
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-
static struct kvm_clock_pairing clock_pair;
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static phys_addr_t clock_pair_gpa;
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-
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static int ptp_kvm_get_time_fn(ktime_t *device_time,
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struct system_counterval_t *system_counter,
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void *ctx)
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{
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-
unsigned long ret;
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long ret;
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u64 cycle;
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struct timespec64 tspec;
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-
unsigned version;
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int cpu;
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struct pvclock_vcpu_time_info *src;
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struct clocksource *cs;
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spin_lock(&kvm_ptp_lock);
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preempt_disable_notrace();
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cpu = smp_processor_id();
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src = &hv_clock[cpu].pvti;
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-
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do {
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/*
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* We are using a TSC value read in the hosts
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* kvm_hc_clock_pairing handling.
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* So any changes to tsc_to_system_mul
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* and tsc_shift or any other pvclock
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* data invalidate that measurement.
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*/
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version = pvclock_read_begin(src);
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-
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
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clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret != 0) {
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pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);
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spin_unlock(&kvm_ptp_lock);
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preempt_enable_notrace();
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return -EOPNOTSUPP;
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}
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-
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tspec.tv_sec = clock_pair.sec;
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tspec.tv_nsec = clock_pair.nsec;
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ret = __pvclock_read_cycles(src, clock_pair.tsc);
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} while (pvclock_read_retry(src, version));
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ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs);
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if (ret) {
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spin_unlock(&kvm_ptp_lock);
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preempt_enable_notrace();
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return ret;
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}
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preempt_enable_notrace();
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-
system_counter->cycles = ret;
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system_counter->cs = &kvm_clock;
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system_counter->cycles = cycle;
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system_counter->cs = cs;
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*device_time = timespec64_to_ktime(tspec);
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···
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static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
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{
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unsigned long ret;
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long ret;
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struct timespec64 tspec;
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spin_lock(&kvm_ptp_lock);
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
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clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret != 0) {
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pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);
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ret = kvm_arch_ptp_get_clock(&tspec);
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if (ret) {
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spin_unlock(&kvm_ptp_lock);
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return -EOPNOTSUPP;
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return ret;
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}
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tspec.tv_sec = clock_pair.sec;
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tspec.tv_nsec = clock_pair.nsec;
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spin_unlock(&kvm_ptp_lock);
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memcpy(ts, &tspec, sizeof(struct timespec64));
···
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{
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long ret;
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if (!kvm_para_available())
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return -ENODEV;
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clock_pair_gpa = slow_virt_to_phys(&clock_pair);
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hv_clock = pvclock_get_pvti_cpu0_va();
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if (!hv_clock)
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return -ENODEV;
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-
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)
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return -ENODEV;
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ret = kvm_arch_ptp_init();
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if (ret) {
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pr_err("fail to initialize ptp_kvm");
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return ret;
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}
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kvm_ptp_clock.caps = ptp_kvm_caps;
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+97
drivers/ptp/ptp_kvm_x86.c
+97
drivers/ptp/ptp_kvm_x86.c
···
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// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Virtual PTP 1588 clock for use with KVM guests
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*
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* Copyright (C) 2017 Red Hat Inc.
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*/
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#include <linux/device.h>
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#include <linux/kernel.h>
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#include <asm/pvclock.h>
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#include <asm/kvmclock.h>
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#include <linux/module.h>
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#include <uapi/asm/kvm_para.h>
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#include <uapi/linux/kvm_para.h>
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#include <linux/ptp_clock_kernel.h>
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#include <linux/ptp_kvm.h>
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struct pvclock_vsyscall_time_info *hv_clock;
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static phys_addr_t clock_pair_gpa;
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static struct kvm_clock_pairing clock_pair;
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int kvm_arch_ptp_init(void)
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{
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long ret;
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if (!kvm_para_available())
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return -ENODEV;
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clock_pair_gpa = slow_virt_to_phys(&clock_pair);
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hv_clock = pvclock_get_pvti_cpu0_va();
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if (!hv_clock)
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return -ENODEV;
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)
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return -ENODEV;
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return 0;
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}
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int kvm_arch_ptp_get_clock(struct timespec64 *ts)
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{
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long ret;
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
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clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret != 0) {
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pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);
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return -EOPNOTSUPP;
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}
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ts->tv_sec = clock_pair.sec;
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ts->tv_nsec = clock_pair.nsec;
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return 0;
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}
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int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,
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struct clocksource **cs)
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{
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struct pvclock_vcpu_time_info *src;
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unsigned int version;
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long ret;
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int cpu;
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cpu = smp_processor_id();
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src = &hv_clock[cpu].pvti;
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do {
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/*
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* We are using a TSC value read in the hosts
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* kvm_hc_clock_pairing handling.
76
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* So any changes to tsc_to_system_mul
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* and tsc_shift or any other pvclock
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* data invalidate that measurement.
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*/
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version = pvclock_read_begin(src);
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ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
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clock_pair_gpa,
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KVM_CLOCK_PAIRING_WALLCLOCK);
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if (ret != 0) {
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pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);
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return -EOPNOTSUPP;
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}
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tspec->tv_sec = clock_pair.sec;
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tspec->tv_nsec = clock_pair.nsec;
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*cycle = __pvclock_read_cycles(src, clock_pair.tsc);
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} while (pvclock_read_retry(src, version));
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*cs = &kvm_clock;
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return 0;
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}
+19
include/linux/ptp_kvm.h
+19
include/linux/ptp_kvm.h
···
1
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/* SPDX-License-Identifier: GPL-2.0-or-later */
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/*
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* Virtual PTP 1588 clock for use with KVM guests
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*
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* Copyright (C) 2017 Red Hat Inc.
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*/
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8
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#ifndef _PTP_KVM_H_
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#define _PTP_KVM_H_
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struct timespec64;
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struct clocksource;
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int kvm_arch_ptp_init(void);
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int kvm_arch_ptp_get_clock(struct timespec64 *ts);
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int kvm_arch_ptp_get_crosststamp(u64 *cycle,
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struct timespec64 *tspec, struct clocksource **cs);
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#endif /* _PTP_KVM_H_ */