[thirdparty/kernel/stable.git] / arch / x86 / include / asm / virtext.h

/* 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 <ehabkost@redhat.com>
 *
 * 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>
#include <asm/tlbflush.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 */
}


/** Disable VMX on the current CPU
 *
 * vmxoff causes a undefined-opcode exception if vmxon was not run
 * on the CPU previously. Only call this function if you know VMX
 * is enabled.
 */
static inline void cpu_vmxoff(void)
{
	asm volatile (ASM_VMX_VMXOFF : : : "cc");
	cr4_clear_bits(X86_CR4_VMXE);
}

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

/** Disable VMX if it is enabled on the current CPU
 *
 * You shouldn't call this if cpu_has_vmx() returns 0.
 */
static inline void __cpu_emergency_vmxoff(void)
{
	if (cpu_vmx_enabled())
		cpu_vmxoff();
}

/** Disable VMX if it is supported and enabled on the current CPU
 */
static inline void cpu_emergency_vmxoff(void)
{
	if (cpu_has_vmx())
		__cpu_emergency_vmxoff();
}


/*
 * SVM functions:
 */

/** Check if the CPU has SVM support
 *
 * You can use the 'msg' arg to get a message describing the problem,
 * if the function returns zero. Simply pass NULL if you are not interested
 * on the messages; gcc should take care of not generating code for
 * the messages on this case.
 */
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;
}


/** Disable SVM on the current CPU
 *
 * You should call this only if cpu_has_svm() returned true.
 */
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);
}

/** Makes sure SVM is disabled, if it is supported on the CPU
 */
static inline void cpu_emergency_svm_disable(void)
{
	if (cpu_has_svm(NULL))
		cpu_svm_disable();
}

#endif /* _ASM_X86_VIRTEX_H */
Commit	Line	Data
6210e37b EH	1	/* CPU virtualization extensions handling
	2	*
	3	* This should carry the code for handling CPU virtualization extensions
	4	* that needs to live in the kernel core.
	5	*
	6	* Author: Eduardo Habkost <ehabkost@redhat.com>
	7	*
	8	* Copyright (C) 2008, Red Hat Inc.
	9	*
	10	* Contains code from KVM, Copyright (C) 2006 Qumranet, Inc.
	11	*
	12	* This work is licensed under the terms of the GNU GPL, version 2. See
	13	* the COPYING file in the top-level directory.
	14	*/
	15	#ifndef _ASM_X86_VIRTEX_H
	16	#define _ASM_X86_VIRTEX_H
	17
	18	#include <asm/processor.h>
6210e37b	19
1e993114	20	#include <asm/vmx.h>
63d1142f	21	#include <asm/svm.h>
375074cc	22	#include <asm/tlbflush.h>
1e993114	23
6210e37b EH	24	/*
	25	* VMX functions:
	26	*/
	27
	28	static inline int cpu_has_vmx(void)
	29	{
	30	unsigned long ecx = cpuid_ecx(1);
	31	return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
	32	}
	33
1e993114 EH	34
	35	/** Disable VMX on the current CPU
	36	*
	37	* vmxoff causes a undefined-opcode exception if vmxon was not run
	38	* on the CPU previously. Only call this function if you know VMX
	39	* is enabled.
	40	*/
	41	static inline void cpu_vmxoff(void)
	42	{
	43	asm volatile (ASM_VMX_VMXOFF : : : "cc");
375074cc	44	cr4_clear_bits(X86_CR4_VMXE);
1e993114 EH	45	}
1e993114 EH	46
6aa07a0d EH	47	static inline int cpu_vmx_enabled(void)
	48	{
	49	return read_cr4() & X86_CR4_VMXE;
	50	}
	51
	52	/** Disable VMX if it is enabled on the current CPU
	53	*
	54	* You shouldn't call this if cpu_has_vmx() returns 0.
	55	*/
	56	static inline void __cpu_emergency_vmxoff(void)
	57	{
	58	if (cpu_vmx_enabled())
	59	cpu_vmxoff();
	60	}
	61
	62	/** Disable VMX if it is supported and enabled on the current CPU
	63	*/
	64	static inline void cpu_emergency_vmxoff(void)
	65	{
	66	if (cpu_has_vmx())
	67	__cpu_emergency_vmxoff();
	68	}
	69
63d1142f EH	70
	71
	72
	73	/*
	74	* SVM functions:
	75	*/
	76
	77	/** Check if the CPU has SVM support
	78	*
	79	* You can use the 'msg' arg to get a message describing the problem,
	80	* if the function returns zero. Simply pass NULL if you are not interested
	81	* on the messages; gcc should take care of not generating code for
	82	* the messages on this case.
	83	*/
	84	static inline int cpu_has_svm(const char **msg)
	85	{
	86	uint32_t eax, ebx, ecx, edx;
	87
	88	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
	89	if (msg)
	90	*msg = "not amd";
	91	return 0;
	92	}
	93
	94	cpuid(0x80000000, &eax, &ebx, &ecx, &edx);
	95	if (eax < SVM_CPUID_FUNC) {
	96	if (msg)
	97	*msg = "can't execute cpuid_8000000a";
	98	return 0;
	99	}
	100
	101	cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
	102	if (!(ecx & (1 << SVM_CPUID_FEATURE_SHIFT))) {
	103	if (msg)
	104	*msg = "svm not available";
	105	return 0;
	106	}
	107	return 1;
	108	}
	109
2c8dceeb EH	110
	111	/** Disable SVM on the current CPU
	112	*
	113	* You should call this only if cpu_has_svm() returned true.
	114	*/
	115	static inline void cpu_svm_disable(void)
	116	{
	117	uint64_t efer;
	118
	119	wrmsrl(MSR_VM_HSAVE_PA, 0);
	120	rdmsrl(MSR_EFER, efer);
9962d032	121	wrmsrl(MSR_EFER, efer & ~EFER_SVME);
2c8dceeb EH	122	}
2c8dceeb EH	123
0f3e9eeb EH	124	/** Makes sure SVM is disabled, if it is supported on the CPU
	125	*/
	126	static inline void cpu_emergency_svm_disable(void)
	127	{
	128	if (cpu_has_svm(NULL))
	129	cpu_svm_disable();
	130	}
	131
6210e37b	132	#endif /* _ASM_X86_VIRTEX_H */