Right now there is only a pvclock_pvti_cpu0_va() which is defined
on kvmclock since:
commit dac16fba6fc5
("x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap")
The only user of this interface so far is kvm. This commit adds a
setter function for the pvti page and moves pvclock_pvti_cpu0_va
to pvclock, which is a more generic place to have it; and would
allow other PV clocksources to use it, such as Xen.
While moving pvclock_pvti_cpu0_va into pvclock, rename also this
function to pvclock_get_pvti_cpu0_va (including its call sites)
to be symmetric with the setter (pvclock_set_pvti_cpu0_va).
Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
Changes since v7:
* Add Paolo Acked-by
(Comments from Thomas Gleixner)
* Rename getter to pvclock_get_pvti_cpu0_va
and fixup its callsites (vdso/vma.c and ptp/ptp_kvm.c)
* Add Thomas Acked-by
Changes since v1:
* Rebased: the only conflict was that I had move the export
pvclock_pvti_cpu0_va() symbol as it is used by kvm PTP driver.
* Do not initialize pvti_cpu0_va to NULL (checkpatch error)
( Comments from Andy Lutomirski )
* Removed asm/pvclock.h 'pvclock_set_pvti_cpu0_va' definition
for non !PARAVIRT_CLOCK to better track screwed Kconfig stuff.
* Add his Acked-by (provided the previous adjustment was made)
Changes since RFC:
(Comments from Andy Lutomirski)
* Add __init to pvclock_set_pvti_cpu0_va
* Add WARN_ON(vclock_was_used(VCLOCK_PVCLOCK)) to
pvclock_set_pvti_cpu0_va
---
arch/x86/entry/vdso/vma.c | 2 +-
arch/x86/include/asm/pvclock.h | 19 ++++++++++---------
arch/x86/kernel/kvmclock.c | 7 +------
arch/x86/kernel/pvclock.c | 14 ++++++++++++++
drivers/ptp/ptp_kvm.c | 2 +-
5 files changed, 27 insertions(+), 17 deletions(-)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 1911310959f8..a77fd3c8d824 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -112,7 +112,7 @@ static int vvar_fault(const struct vm_special_mapping *sm,
__pa_symbol(&__vvar_page) >> PAGE_SHIFT);
} else if (sym_offset == image->sym_pvclock_page) {
struct pvclock_vsyscall_time_info *pvti =
- pvclock_pvti_cpu0_va();
+ pvclock_get_pvti_cpu0_va();
if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) {
ret = vm_insert_pfn(
vma,
diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index 448cfe1b48cf..55325f934d71 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h
@@ -4,15 +4,6 @@
#include <linux/clocksource.h>
#include <asm/pvclock-abi.h>
-#ifdef CONFIG_KVM_GUEST
-extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void);
-#else
-static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
-{
- return NULL;
-}
-#endif
-
/* some helper functions for xen and kvm pv clock sources */
u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);
u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src);
@@ -101,4 +92,14 @@ struct pvclock_vsyscall_time_info {
#define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)
+#ifdef CONFIG_PARAVIRT_CLOCK
+void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti);
+struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void);
+#else
+static inline struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void)
+{
+ return NULL;
+}
+#endif
+
#endif /* _ASM_X86_PVCLOCK_H */
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index d88967659098..538738047ff5 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -47,12 +47,6 @@ early_param("no-kvmclock", parse_no_kvmclock);
static struct pvclock_vsyscall_time_info *hv_clock;
static struct pvclock_wall_clock wall_clock;
-struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
-{
- return hv_clock;
-}
-EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va);
-
/*
* The wallclock is the time of day when we booted. Since then, some time may
* have elapsed since the hypervisor wrote the data. So we try to account for
@@ -334,6 +328,7 @@ int __init kvm_setup_vsyscall_timeinfo(void)
return 1;
}
+ pvclock_set_pvti_cpu0_va(hv_clock);
put_cpu();
kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index 5c3f6d6a5078..761f6af6efa5 100644
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -25,8 +25,10 @@
#include <asm/fixmap.h>
#include <asm/pvclock.h>
+#include <asm/vgtod.h>
static u8 valid_flags __read_mostly = 0;
+static struct pvclock_vsyscall_time_info *pvti_cpu0_va __read_mostly;
void pvclock_set_flags(u8 flags)
{
@@ -144,3 +146,15 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);
}
+
+void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti)
+{
+ WARN_ON(vclock_was_used(VCLOCK_PVCLOCK));
+ pvti_cpu0_va = pvti;
+}
+
+struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void)
+{
+ return pvti_cpu0_va;
+}
+EXPORT_SYMBOL_GPL(pvclock_get_pvti_cpu0_va);
diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm.c
index e04d7b2ecb3a..c67dd11e08b1 100644
--- a/drivers/ptp/ptp_kvm.c
+++ b/drivers/ptp/ptp_kvm.c
@@ -182,7 +182,7 @@ static int __init ptp_kvm_init(void)
return -ENODEV;
clock_pair_gpa = slow_virt_to_phys(&clock_pair);
- hv_clock = pvclock_pvti_cpu0_va();
+ hv_clock = pvclock_get_pvti_cpu0_va();
if (!hv_clock)
return -ENODEV;
--
2.11.0
