/*
* Copyright (c) 2006-2012 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
#include <pexpert/pexpert.h>
#include <i386/cpuid.h>
#include <i386/cpu_data.h>
#include <i386/mp.h>
#include <i386/proc_reg.h>
#include <i386/vmx.h>
#include <i386/vmx/vmx_asm.h>
#include <i386/vmx/vmx_shims.h>
#include <i386/vmx/vmx_cpu.h>
#include <mach/mach_host.h> /* for host_info() */
#define VMX_KPRINTF(x...) /* kprintf("vmx: " x) */
int vmx_use_count = 0;
boolean_t vmx_exclusive = FALSE;
static LCK_GRP_DECLARE(vmx_lck_grp, "vmx");
static LCK_MTX_DECLARE(vmx_lck_mtx, &vmx_lck_grp);
/* -----------------------------------------------------------------------------
* vmx_is_available()
* Is the VMX facility available on this CPU?
* -------------------------------------------------------------------------- */
static inline boolean_t
vmx_is_available(void)
{
return 0 != (cpuid_features() & CPUID_FEATURE_VMX);
}
/* -----------------------------------------------------------------------------
* vmxon_is_enabled()
* Is the VMXON instruction enabled on this CPU?
* -------------------------------------------------------------------------- */
static inline boolean_t
vmxon_is_enabled(void)
{
return vmx_is_available() &&
(rdmsr64(MSR_IA32_FEATURE_CONTROL) & MSR_IA32_FEATCTL_VMXON);
}
#if MACH_ASSERT
/* -----------------------------------------------------------------------------
* vmx_is_cr0_valid()
* Is CR0 valid for executing VMXON on this CPU?
* -------------------------------------------------------------------------- */
static inline boolean_t
vmx_is_cr0_valid(vmx_specs_t *specs)
{
uintptr_t cr0 = get_cr0();
return 0 == ((~cr0 & specs->cr0_fixed_0) | (cr0 & ~specs->cr0_fixed_1));
}
/* -----------------------------------------------------------------------------
* vmx_is_cr4_valid()
* Is CR4 valid for executing VMXON on this CPU?
* -------------------------------------------------------------------------- */
static inline boolean_t
vmx_is_cr4_valid(vmx_specs_t *specs)
{
uintptr_t cr4 = get_cr4();
return 0 == ((~cr4 & specs->cr4_fixed_0) | (cr4 & ~specs->cr4_fixed_1));
}
#endif
static void
vmx_enable(void)
{
uint64_t msr_image;
if (!vmx_is_available()) {
return;
}
/*
* We don't count on EFI initializing MSR_IA32_FEATURE_CONTROL
* and turning VMXON on and locking the bit, so we do that now.
*/
msr_image = rdmsr64(MSR_IA32_FEATURE_CONTROL);
if (0 == ((msr_image & MSR_IA32_FEATCTL_LOCK))) {
wrmsr64(MSR_IA32_FEATURE_CONTROL,
(msr_image |
MSR_IA32_FEATCTL_VMXON |
MSR_IA32_FEATCTL_LOCK));
}
set_cr4(get_cr4() | CR4_VMXE);
}
/* -----------------------------------------------------------------------------
* vmx_get_specs()
* Obtain VMX facility specifications for this CPU and
* enter them into the vmx_specs_t structure. If VMX is not available or
* disabled on this CPU, set vmx_present to false and return leaving
* the remainder of the vmx_specs_t uninitialized.
* -------------------------------------------------------------------------- */
void
vmx_cpu_init()
{
vmx_specs_t *specs = ¤t_cpu_datap()->cpu_vmx.specs;
vmx_enable();
VMX_KPRINTF("[%d]vmx_cpu_init() initialized: %d\n",
cpu_number(), specs->initialized);
/* if we have read the data on boot, we won't read it again on wakeup */
if (specs->initialized) {
return;
} else {
specs->initialized = TRUE;
}
/* See if VMX is present, return if it is not */
specs->vmx_present = vmx_is_available() && vmxon_is_enabled();
VMX_KPRINTF("[%d]vmx_cpu_init() vmx_present: %d\n",
cpu_number(), specs->vmx_present);
if (!specs->vmx_present) {
return;
}
#define rdmsr_mask(msr, mask) (uint32_t)(rdmsr64(msr) & (mask))
specs->vmcs_id = rdmsr_mask(MSR_IA32_VMX_BASIC, VMX_VCR_VMCS_REV_ID);
/* Obtain VMX-fixed bits in CR0 */
specs->cr0_fixed_0 = rdmsr_mask(MSR_IA32_VMX_CR0_FIXED0, 0xFFFFFFFF);
specs->cr0_fixed_1 = rdmsr_mask(MSR_IA32_VMX_CR0_FIXED1, 0xFFFFFFFF);
/* Obtain VMX-fixed bits in CR4 */
specs->cr4_fixed_0 = rdmsr_mask(MSR_IA32_VMX_CR4_FIXED0, 0xFFFFFFFF);
specs->cr4_fixed_1 = rdmsr_mask(MSR_IA32_VMX_CR4_FIXED1, 0xFFFFFFFF);
}
/* -----------------------------------------------------------------------------
* vmx_on()
* Enter VMX root operation on this CPU.
* -------------------------------------------------------------------------- */
static void
vmx_on(void *arg __unused)
{
vmx_cpu_t *cpu = ¤t_cpu_datap()->cpu_vmx;
addr64_t vmxon_region_paddr;
int result;
VMX_KPRINTF("[%d]vmx_on() entry state: %d\n",
cpu_number(), cpu->specs.vmx_on);
assert(cpu->specs.vmx_present);
if (NULL == cpu->vmxon_region) {
panic("vmx_on: VMXON region not allocated");
}
vmxon_region_paddr = vmx_paddr(cpu->vmxon_region);
/*
* Enable VMX operation.
*/
if (FALSE == cpu->specs.vmx_on) {
assert(vmx_is_cr0_valid(&cpu->specs));
assert(vmx_is_cr4_valid(&cpu->specs));
result = __vmxon(vmxon_region_paddr);
if (result != VMX_SUCCEED) {
panic("vmx_on: unexpected return %d from __vmxon()", result);
}
cpu->specs.vmx_on = TRUE;
}
VMX_KPRINTF("[%d]vmx_on() return state: %d\n",
cpu_number(), cpu->specs.vmx_on);
}
/* -----------------------------------------------------------------------------
* vmx_off()
* Leave VMX root operation on this CPU.
* -------------------------------------------------------------------------- */
static void
vmx_off(void *arg __unused)
{
vmx_cpu_t *cpu = ¤t_cpu_datap()->cpu_vmx;
int result;
VMX_KPRINTF("[%d]vmx_off() entry state: %d\n",
cpu_number(), cpu->specs.vmx_on);
if (TRUE == cpu->specs.vmx_on) {
/* Tell the CPU to release the VMXON region */
result = __vmxoff();
if (result != VMX_SUCCEED) {
panic("vmx_off: unexpected return %d from __vmxoff()", result);
}
cpu->specs.vmx_on = FALSE;
}
VMX_KPRINTF("[%d]vmx_off() return state: %d\n",
cpu_number(), cpu->specs.vmx_on);
}
/* -----------------------------------------------------------------------------
* vmx_allocate_vmxon_regions()
* Allocate, clear and init VMXON regions for all CPUs.
* -------------------------------------------------------------------------- */
static void
vmx_allocate_vmxon_regions(void)
{
unsigned int i;
for (i = 0; i < real_ncpus; i++) {
vmx_cpu_t *cpu = &cpu_datap(i)->cpu_vmx;
/* The size is defined to be always <= 4K, so we just allocate a page */
cpu->vmxon_region = vmx_pcalloc();
if (NULL == cpu->vmxon_region) {
panic("vmx_allocate_vmxon_regions: unable to allocate VMXON region");
}
*(uint32_t*)(cpu->vmxon_region) = cpu->specs.vmcs_id;
}
}
/* -----------------------------------------------------------------------------
* vmx_free_vmxon_regions()
* Free VMXON regions for all CPUs.
* -------------------------------------------------------------------------- */
static void
vmx_free_vmxon_regions(void)
{
unsigned int i;
for (i = 0; i < real_ncpus; i++) {
vmx_cpu_t *cpu = &cpu_datap(i)->cpu_vmx;
vmx_pfree(cpu->vmxon_region);
cpu->vmxon_region = NULL;
}
}
/* -----------------------------------------------------------------------------
* vmx_globally_available()
* Checks whether VT can be turned on for all CPUs.
* -------------------------------------------------------------------------- */
static boolean_t
vmx_globally_available(void)
{
unsigned int i;
unsigned int ncpus = ml_wait_max_cpus();
boolean_t available = TRUE;
for (i = 0; i < ncpus; i++) {
vmx_cpu_t *cpu = &cpu_datap(i)->cpu_vmx;
if (!cpu->specs.vmx_present) {
available = FALSE;
}
}
VMX_KPRINTF("VMX available: %d\n", available);
return available;
}
/* -----------------------------------------------------------------------------
* vmx_turn_on()
* Turn on VT operation on all CPUs.
* -------------------------------------------------------------------------- */
int
host_vmxon(boolean_t exclusive)
{
int error;
assert(0 == get_preemption_level());
if (!vmx_globally_available()) {
return VMX_UNSUPPORTED;
}
lck_mtx_lock(&vmx_lck_mtx);
if (vmx_exclusive || (exclusive && vmx_use_count)) {
error = VMX_INUSE;
} else {
if (0 == vmx_use_count) {
vmx_allocate_vmxon_regions();
vmx_exclusive = exclusive;
vmx_use_count = 1;
mp_cpus_call(CPUMASK_ALL, ASYNC, vmx_on, NULL);
} else {
vmx_use_count++;
}
VMX_KPRINTF("VMX use count: %d\n", vmx_use_count);
error = VMX_OK;
}
lck_mtx_unlock(&vmx_lck_mtx);
return error;
}
/* -----------------------------------------------------------------------------
* vmx_turn_off()
* Turn off VT operation on all CPUs.
* -------------------------------------------------------------------------- */
void
host_vmxoff()
{
assert(0 == get_preemption_level());
lck_mtx_lock(&vmx_lck_mtx);
if (1 == vmx_use_count) {
vmx_exclusive = FALSE;
vmx_use_count = 0;
mp_cpus_call(CPUMASK_ALL, ASYNC, vmx_off, NULL);
vmx_free_vmxon_regions();
} else {
vmx_use_count--;
}
lck_mtx_unlock(&vmx_lck_mtx);
VMX_KPRINTF("VMX use count: %d\n", vmx_use_count);
}
/* -----------------------------------------------------------------------------
* vmx_suspend()
* Turn off VT operation on this CPU if it was on.
* Called when a CPU goes offline.
* -------------------------------------------------------------------------- */
void
vmx_suspend()
{
VMX_KPRINTF("vmx_suspend\n");
if (vmx_use_count) {
vmx_off(NULL);
}
}
/* -----------------------------------------------------------------------------
* vmx_suspend()
* Restore the previous VT state. Called when CPU comes back online.
* -------------------------------------------------------------------------- */
void
vmx_resume(boolean_t is_wake_from_hibernate)
{
VMX_KPRINTF("vmx_resume\n");
vmx_enable();
if (vmx_use_count == 0) {
return;
}
/*
* When resuming from hiberate on the boot cpu,
* we must mark VMX as off since that's the state at wake-up
* because the restored state in memory records otherwise.
* This results in vmx_on() doing the right thing.
*/
if (is_wake_from_hibernate) {
vmx_cpu_t *cpu = ¤t_cpu_datap()->cpu_vmx;
cpu->specs.vmx_on = FALSE;
}
vmx_on(NULL);
}
/* -----------------------------------------------------------------------------
* vmx_hv_support()
* Determine if the VMX feature set is sufficent for kernel HV support.
* -------------------------------------------------------------------------- */
boolean_t
vmx_hv_support()
{
if (!vmx_is_available()) {
return FALSE;
}
#define CHK(msr, shift, mask) if (!VMX_CAP(msr, shift, mask)) return FALSE;
/* 'EPT' and 'Unrestricted Mode' are part of the secondary processor-based
* VM-execution controls */
CHK(MSR_IA32_VMX_BASIC, 0, VMX_BASIC_TRUE_CTLS)
CHK(MSR_IA32_VMX_TRUE_PROCBASED_CTLS, 32, VMX_TRUE_PROCBASED_SECONDARY_CTLS)
/* if we have these, check for 'EPT' and 'Unrestricted Mode' */
CHK(MSR_IA32_VMX_PROCBASED_CTLS2, 32, VMX_PROCBASED_CTLS2_EPT)
CHK(MSR_IA32_VMX_PROCBASED_CTLS2, 32, VMX_PROCBASED_CTLS2_UNRESTRICTED)
return TRUE;
}