x86/pvclock: add setter for pvclock_pvti_cpu0_va

Right now there is only a pvclock_pvti_cpu0_va() which is defined
on kvmclock since:

commit dac16fba6f
("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@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
This commit is contained in:
Joao Martins 2017-11-08 17:19:55 +00:00 committed by Boris Ostrovsky
parent 001f60e1f6
commit 9f08890ab9
5 changed files with 27 additions and 17 deletions

View File

@ -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,

View File

@ -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 */

View File

@ -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;

View File

@ -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);

View File

@ -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;