x86/vdso: Give the [ph]vclock_page declarations real types

#define VDSO_HAS_CLOCK_GETRES 1

/*

 * Declare the memory-mapped vclock data pages.  These come from hypervisors.

 * If we ever reintroduce something like direct access to an MMIO clock like

 * the HPET again, it will go here as well.

 *

 * A load from any of these pages will segfault if the clock in question is

 * disabled, so appropriate compiler barriers and checks need to be used

 * to prevent stray loads.

 *

 * These declarations MUST NOT be const.  The compiler will assume that

 * an extern const variable has genuinely constant contents, and the

 * resulting code won't work, since the whole point is that these pages

 * change over time, possibly while we're accessing them.

 */

#ifdef CONFIG_PARAVIRT_CLOCK

extern u8 pvclock_page[PAGE_SIZE]

/*

 * This is the vCPU 0 pvclock page.  We only use pvclock from the vDSO

 * if the hypervisor tells us that all vCPUs can get valid data from the

 * vCPU 0 page.

 */

extern struct pvclock_vsyscall_time_info pvclock_page

	__attribute__((visibility("hidden")));

#endif

#ifdef CONFIG_HYPERV_TSCPAGE

extern u8 hvclock_page[PAGE_SIZE]

extern struct ms_hyperv_tsc_page hvclock_page

	__attribute__((visibility("hidden")));

#endif

#endif

#ifdef CONFIG_PARAVIRT_CLOCK

static const struct pvclock_vsyscall_time_info *get_pvti0(void)

{

	return (const struct pvclock_vsyscall_time_info *)&pvclock_page;

}

static u64 vread_pvclock(void)

{

	const struct pvclock_vcpu_time_info *pvti = &get_pvti0()->pvti;

	const struct pvclock_vcpu_time_info *pvti = &pvclock_page.pvti;

	u32 version;

	u64 ret;

#ifdef CONFIG_HYPERV_TSCPAGE

static u64 vread_hvclock(void)

{

	const struct ms_hyperv_tsc_page *tsc_pg =

		(const struct ms_hyperv_tsc_page *)&hvclock_page;

	return hv_read_tsc_page(tsc_pg);

	return hv_read_tsc_page(&hvclock_page);

}

#endif