1// Copyright 2018 The Fuchsia Authors 2// 3// Use of this source code is governed by a MIT-style 4// license that can be found in the LICENSE file or at 5// https://opensource.org/licenses/MIT 6 7#pragma once 8 9#include <hypervisor/guest_physical_address_space.h> 10#include <zircon/types.h> 11 12struct PvClockState; 13 14// This structure contains mapping between TSC and host wall time at some point 15// in time. KVM has a hypercall that asks the VMM to populate this structure and 16// it's actually used, which is rather puzzling considering that PV clock 17// provides an API to get wall time at the time of boot and offset from that time 18// which seem to be enough. 19// 20// More detailed description of KVM API is available here: 21// https://www.kernel.org/doc/Documentation/virtual/kvm/hypercalls.txt 22struct PvClockOffset { 23 uint64_t sec; 24 uint64_t nsec; 25 uint64_t tsc; 26 uint32_t flags; 27 uint32_t unused[9]; 28} __PACKED; 29 30// Updates guest boot time. 31zx_status_t pvclock_update_boot_time(hypervisor::GuestPhysicalAddressSpace* gpas, 32 zx_vaddr_t guest_paddr); 33 34// Remembers guest physical address for KVM clock system time structure and enables updates 35// to guest system time. 36zx_status_t pvclock_reset_clock(PvClockState* pvclock, hypervisor::GuestPhysicalAddressSpace* gpas, 37 zx_vaddr_t guest_paddr); 38 39// Disables updates to guest system time. 40void pvclock_stop_clock(PvClockState* pvclock); 41 42// Updates guest system time. If updates disabled does nothing. 43void pvclock_update_system_time(PvClockState* pvclock, hypervisor::GuestPhysicalAddressSpace* gpas); 44 45// Populates mapping between TSC and wall time per guest request. guest_padds contains 46// physical address of PvClockOffset structure where the result should be stored. 47zx_status_t pvclock_populate_offset(hypervisor::GuestPhysicalAddressSpace* gpas, 48 zx_vaddr_t guest_paddr); 49