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

/* SPDX-License-Identifier: GPL-2.0-only */
/* 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.
 */
#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 ("vmxoff");
	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)
{
	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) {
		if (msg)
			*msg = "not amd or hygon";
		return 0;
	}

	if (boot_cpu_data.extended_cpuid_level < SVM_CPUID_FUNC) {
		if (msg)
			*msg = "can't execute cpuid_8000000a";
		return 0;
	}

	if (!boot_cpu_has(X86_FEATURE_SVM)) {
		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
20c8ccb1	1	/* SPDX-License-Identifier: GPL-2.0-only */
6210e37b EH	2	/* CPU virtualization extensions handling
	3	*
	4	* This should carry the code for handling CPU virtualization extensions
	5	* that needs to live in the kernel core.
	6	*
	7	* Author: Eduardo Habkost <ehabkost@redhat.com>
	8	*
	9	* Copyright (C) 2008, Red Hat Inc.
	10	*
	11	* Contains code from KVM, Copyright (C) 2006 Qumranet, Inc.
6210e37b EH	12	*/
	13	#ifndef _ASM_X86_VIRTEX_H
	14	#define _ASM_X86_VIRTEX_H
	15
	16	#include <asm/processor.h>
6210e37b	17
1e993114	18	#include <asm/vmx.h>
63d1142f	19	#include <asm/svm.h>
375074cc	20	#include <asm/tlbflush.h>
1e993114	21
6210e37b EH	22	/*
	23	* VMX functions:
	24	*/
	25
	26	static inline int cpu_has_vmx(void)
	27	{
	28	unsigned long ecx = cpuid_ecx(1);
	29	return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
	30	}
	31
1e993114 EH	32
	33	/** Disable VMX on the current CPU
	34	*
	35	* vmxoff causes a undefined-opcode exception if vmxon was not run
	36	* on the CPU previously. Only call this function if you know VMX
	37	* is enabled.
	38	*/
	39	static inline void cpu_vmxoff(void)
	40	{
4b1e5478	41	asm volatile ("vmxoff");
375074cc	42	cr4_clear_bits(X86_CR4_VMXE);
1e993114 EH	43	}
1e993114 EH	44
6aa07a0d EH	45	static inline int cpu_vmx_enabled(void)
6aa07a0d EH	46	{
1e02ce4c	47	return __read_cr4() & X86_CR4_VMXE;
6aa07a0d EH	48	}
	49
	50	/** Disable VMX if it is enabled on the current CPU
	51	*
	52	* You shouldn't call this if cpu_has_vmx() returns 0.
	53	*/
	54	static inline void __cpu_emergency_vmxoff(void)
	55	{
	56	if (cpu_vmx_enabled())
	57	cpu_vmxoff();
	58	}
	59
	60	/** Disable VMX if it is supported and enabled on the current CPU
	61	*/
	62	static inline void cpu_emergency_vmxoff(void)
	63	{
	64	if (cpu_has_vmx())
	65	__cpu_emergency_vmxoff();
	66	}
	67
63d1142f EH	68
	69
	70
	71	/*
	72	* SVM functions:
	73	*/
	74
	75	/** Check if the CPU has SVM support
	76	*
	77	* You can use the 'msg' arg to get a message describing the problem,
	78	* if the function returns zero. Simply pass NULL if you are not interested
	79	* on the messages; gcc should take care of not generating code for
	80	* the messages on this case.
	81	*/
	82	static inline int cpu_has_svm(const char **msg)
	83	{
b8f4abb6 PW	84	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
b8f4abb6 PW	85	boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) {
63d1142f	86	if (msg)
b8f4abb6	87	*msg = "not amd or hygon";
63d1142f EH	88	return 0;
	89	}
	90
682a8108	91	if (boot_cpu_data.extended_cpuid_level < SVM_CPUID_FUNC) {
63d1142f EH	92	if (msg)
	93	*msg = "can't execute cpuid_8000000a";
	94	return 0;
	95	}
	96
682a8108	97	if (!boot_cpu_has(X86_FEATURE_SVM)) {
63d1142f EH	98	if (msg)
	99	*msg = "svm not available";
	100	return 0;
	101	}
	102	return 1;
	103	}
	104
2c8dceeb EH	105
	106	/** Disable SVM on the current CPU
	107	*
	108	* You should call this only if cpu_has_svm() returned true.
	109	*/
	110	static inline void cpu_svm_disable(void)
	111	{
	112	uint64_t efer;
	113
	114	wrmsrl(MSR_VM_HSAVE_PA, 0);
	115	rdmsrl(MSR_EFER, efer);
9962d032	116	wrmsrl(MSR_EFER, efer & ~EFER_SVME);
2c8dceeb EH	117	}
2c8dceeb EH	118
0f3e9eeb EH	119	/** Makes sure SVM is disabled, if it is supported on the CPU
	120	*/
	121	static inline void cpu_emergency_svm_disable(void)
	122	{
	123	if (cpu_has_svm(NULL))
	124	cpu_svm_disable();
	125	}
	126
6210e37b	127	#endif /* _ASM_X86_VIRTEX_H */