[RFC PATCH v9 3/8] ptp: Reorganize ptp_kvm modules to make it arch-independent.

Jianyong Wu
2019-12-10T03:41:01Z

Currently, ptp_kvm modules implementation is only for x86 which includs
large part of arch-specific code. This patch move all of those code
into new arch related file in the same directory.

Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
---
drivers/ptp/Makefile | 1 +
drivers/ptp/ptp_kvm.h | 11 +++
drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 78 +++++-------------
drivers/ptp/ptp_kvm_x86.c | 87 +++++++++++++++++++++
4 files changed, 118 insertions(+), 59 deletions(-)
create mode 100644 drivers/ptp/ptp_kvm.h
rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (63%)
create mode 100644 drivers/ptp/ptp_kvm_x86.c

diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
index 677d1d178a3e..3b7554f56ad9 100644
--- a/drivers/ptp/Makefile
+++ b/drivers/ptp/Makefile
@@ -4,6 +4,7 @@
#

ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o
+ptp_kvm-y := ptp_kvm_$(ARCH).o ptp_kvm_common.o
obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o
obj-$(CONFIG_PTP_1588_CLOCK_DTE) += ptp_dte.o
obj-$(CONFIG_PTP_1588_CLOCK_IXP46X) += ptp_ixp46x.o
diff --git a/drivers/ptp/ptp_kvm.h b/drivers/ptp/ptp_kvm.h
new file mode 100644
index 000000000000..4bf1802bbeb8
--- /dev/null
+++ b/drivers/ptp/ptp_kvm.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ *
+ * Copyright (C) 2017 Red Hat Inc.
+ */
+
+int kvm_arch_ptp_init(void);
+int kvm_arch_ptp_get_clock(struct timespec64 *ts);
+int kvm_arch_ptp_get_crosststamp(unsigned long *cycle,
+ struct timespec64 *tspec, void *cs);
diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm_common.c
similarity index 63%
rename from drivers/ptp/ptp_kvm.c
rename to drivers/ptp/ptp_kvm_common.c
index fc7d0b77e118..60442f70d3fc 100644
--- a/drivers/ptp/ptp_kvm.c
+++ b/drivers/ptp/ptp_kvm_common.c
@@ -8,15 +8,16 @@
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/slab.h>
#include <linux/module.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>

+#include "ptp_kvm.h"
+
struct kvm_ptp_clock {
struct ptp_clock *ptp_clock;
struct ptp_clock_info caps;
@@ -24,56 +25,29 @@ struct kvm_ptp_clock {

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;
+ unsigned long ret, 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 != 0) {
+ pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);
+ spin_unlock(&kvm_ptp_lock);
+ preempt_enable_notrace();
+ return -EOPNOTSUPP;
+ }

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);

@@ -116,17 +90,13 @@ static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)

spin_lock(&kvm_ptp_lock);

- ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
- clock_pair_gpa,
- KVM_CLOCK_PAIRING_WALLCLOCK);
+ ret = kvm_arch_ptp_get_clock(&tspec);
if (ret != 0) {
pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);
spin_unlock(&kvm_ptp_lock);
return -EOPNOTSUPP;
}

- tspec.tv_sec = clock_pair.sec;
- tspec.tv_nsec = clock_pair.nsec;
spin_unlock(&kvm_ptp_lock);

memcpy(ts, &tspec, sizeof(struct timespec64));
@@ -166,21 +136,11 @@ static void __exit ptp_kvm_exit(void)

static int __init ptp_kvm_init(void)
{
- long ret;
-
- if (!kvm_para_available())
- return -ENODEV;
+ int ret;

- 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)
+ return -EOPNOTSUPP;

kvm_ptp_clock.caps = ptp_kvm_caps;

diff --git a/drivers/ptp/ptp_kvm_x86.c b/drivers/ptp/ptp_kvm_x86.c
new file mode 100644
index 000000000000..6c891d7299c6
--- /dev/null
+++ b/drivers/ptp/ptp_kvm_x86.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ *
+ * Copyright (C) 2017 Red Hat Inc.
+ */
+
+#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>
+
+phys_addr_t clock_pair_gpa;
+struct kvm_clock_pairing clock_pair;
+struct pvclock_vsyscall_time_info *hv_clock;
+
+int kvm_arch_ptp_init(void)
+{
+ int 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)
+ return -EOPNOTSUPP;
+
+ ts->tv_sec = clock_pair.sec;
+ ts->tv_nsec = clock_pair.nsec;
+
+ return 0;
+}
+
+int kvm_arch_ptp_get_crosststamp(unsigned long *cycle, struct timespec64 *tspec,
+ struct clocksource **cs)
+{
+ unsigned long ret;
+ unsigned int version;
+ int cpu;
+ struct pvclock_vcpu_time_info *src;
+
+ 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);
+ 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;
+}
--
2.17.1