Commit 9f08890a authored by Joao Martins's avatar Joao Martins Committed by Boris Ostrovsky
Browse files

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 dac16fba
("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: default avatarJoao Martins <joao.m.martins@oracle.com>
Acked-by: default avatarAndy Lutomirski <luto@kernel.org>
Acked-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Acked-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
parent 001f60e1

arch/x86/entry/vdso/vma.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -112,7 +112,7 @@ static int vvar_fault(const struct vm_special_mapping *sm, 
				    __pa_symbol(&__vvar_page) >> PAGE_SHIFT);

				    __pa_symbol(&__vvar_page) >> PAGE_SHIFT);

	} else if (sym_offset == image->sym_pvclock_page) {

	} else if (sym_offset == image->sym_pvclock_page) {

		struct pvclock_vsyscall_time_info *pvti =

		struct pvclock_vsyscall_time_info *pvti =

			pvclock_pvti_cpu0_va();

			pvclock_get_pvti_cpu0_va();

		if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) {

		if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) {

			ret = vm_insert_pfn(

			ret = vm_insert_pfn(

				vma,

				vma,

arch/x86/include/asm/pvclock.h

+10 −9
Original line number Original line Diff line number Diff line
@@ -4,15 +4,6 @@ 
#include <linux/clocksource.h>

#include <linux/clocksource.h>

#include <asm/pvclock-abi.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 */

/* some helper functions for xen and kvm pv clock sources */

u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);

u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);

u8 pvclock_read_flags(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)

#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 */
 
#endif /* _ASM_X86_PVCLOCK_H */

arch/x86/kernel/kvmclock.c

+1 −6
Original line number Original line Diff line number Diff line
@@ -47,12 +47,6 @@ early_param("no-kvmclock", parse_no_kvmclock); 
static struct pvclock_vsyscall_time_info *hv_clock;

static struct pvclock_vsyscall_time_info *hv_clock;

static struct pvclock_wall_clock wall_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

 * 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

 * 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;

		return 1;

	}

	}





	pvclock_set_pvti_cpu0_va(hv_clock);

	put_cpu();

	put_cpu();





	kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;

	kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;

arch/x86/kernel/pvclock.c

+14 −0
Original line number Original line Diff line number Diff line
@@ -25,8 +25,10 @@ 




#include <asm/fixmap.h>

#include <asm/fixmap.h>

#include <asm/pvclock.h>

#include <asm/pvclock.h>

#include <asm/vgtod.h>





static u8 valid_flags __read_mostly = 0;

static u8 valid_flags __read_mostly = 0;

static struct pvclock_vsyscall_time_info *pvti_cpu0_va __read_mostly;





void pvclock_set_flags(u8 flags)

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);

	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);

drivers/ptp/ptp_kvm.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -182,7 +182,7 @@ static int __init ptp_kvm_init(void) 
		return -ENODEV;

		return -ENODEV;





	clock_pair_gpa = slow_virt_to_phys(&clock_pair);

	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)

	if (!hv_clock)

		return -ENODEV;

		return -ENODEV;

CRA Git | Maintained and supported by SUSTech CRA and CCSE