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/* CPU virtualization extensions handling
 *
 * This should carry the code for handling CPU virtualization extensions
 * that needs to live in the kernel core.
 *
 * Author: Eduardo Habkost <[email protected]>
 *
 * Copyright (C) 2008, Red Hat Inc.
 *
 * Contains code from KVM, Copyright (C) 2006 Qumranet, Inc.
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 */
#ifndef _ASM_X86_VIRTEX_H
#define _ASM_X86_VIRTEX_H

#include <asm/processor.h>

#include <asm/vmx.h>
#include <asm/svm.h>

/*
 * VMX functions:
 */

static inline int cpu_has_vmx(void)
{
    unsigned long ecx = cpuid_ecx(1);
    return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
}


static inline void cpu_vmxoff(void)
{
    asm volatile (ASM_VMX_VMXOFF : : : "cc");
    write_cr4(read_cr4() & ~X86_CR4_VMXE);
}

static inline int cpu_vmx_enabled(void)
{
    return read_cr4() & X86_CR4_VMXE;
}

static inline void __cpu_emergency_vmxoff(void)
{
    if (cpu_vmx_enabled())
        cpu_vmxoff();
}

static inline void cpu_emergency_vmxoff(void)
{
    if (cpu_has_vmx())
        __cpu_emergency_vmxoff();
}




/*
 * SVM functions:
 */

static inline int cpu_has_svm(const char **msg)
{
    uint32_t eax, ebx, ecx, edx;

    if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
        if (msg)
            *msg = "not amd";
        return 0;
    }

    cpuid(0x80000000, &eax, &ebx, &ecx, &edx);
    if (eax < SVM_CPUID_FUNC) {
        if (msg)
            *msg = "can't execute cpuid_8000000a";
        return 0;
    }

    cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
    if (!(ecx & (1 << SVM_CPUID_FEATURE_SHIFT))) {
        if (msg)
            *msg = "svm not available";
        return 0;
    }
    return 1;
}


static inline void cpu_svm_disable(void)
{
    uint64_t efer;

    wrmsrl(MSR_VM_HSAVE_PA, 0);
    rdmsrl(MSR_EFER, efer);
    wrmsrl(MSR_EFER, efer & ~EFER_SVME);
}

static inline void cpu_emergency_svm_disable(void)
{
    if (cpu_has_svm(NULL))
        cpu_svm_disable();
}

#endif /* _ASM_X86_VIRTEX_H */