 f05e798ad4
			
		
	
	
	f05e798ad4
	
	
	
		
			
			Disintegrate asm/system.h for X86. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> cc: x86@kernel.org
		
			
				
	
	
		
			131 lines
		
	
	
	
		
			2.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			131 lines
		
	
	
	
		
			2.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /* CPU virtualization extensions handling
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|  *
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|  * This should carry the code for handling CPU virtualization extensions
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|  * that needs to live in the kernel core.
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|  *
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|  * Author: Eduardo Habkost <ehabkost@redhat.com>
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|  *
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|  * Copyright (C) 2008, Red Hat Inc.
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|  *
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|  * Contains code from KVM, Copyright (C) 2006 Qumranet, Inc.
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2.  See
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|  * the COPYING file in the top-level directory.
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|  */
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| #ifndef _ASM_X86_VIRTEX_H
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| #define _ASM_X86_VIRTEX_H
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| 
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| #include <asm/processor.h>
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| 
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| #include <asm/vmx.h>
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| #include <asm/svm.h>
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| 
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| /*
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|  * VMX functions:
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|  */
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| 
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| static inline int cpu_has_vmx(void)
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| {
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| 	unsigned long ecx = cpuid_ecx(1);
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| 	return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
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| }
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| 
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| 
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| /** Disable VMX on the current CPU
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|  *
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|  * vmxoff causes a undefined-opcode exception if vmxon was not run
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|  * on the CPU previously. Only call this function if you know VMX
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|  * is enabled.
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|  */
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| static inline void cpu_vmxoff(void)
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| {
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| 	asm volatile (ASM_VMX_VMXOFF : : : "cc");
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| 	write_cr4(read_cr4() & ~X86_CR4_VMXE);
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| }
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| 
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| static inline int cpu_vmx_enabled(void)
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| {
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| 	return read_cr4() & X86_CR4_VMXE;
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| }
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| 
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| /** Disable VMX if it is enabled on the current CPU
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|  *
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|  * You shouldn't call this if cpu_has_vmx() returns 0.
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|  */
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| static inline void __cpu_emergency_vmxoff(void)
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| {
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| 	if (cpu_vmx_enabled())
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| 		cpu_vmxoff();
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| }
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| 
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| /** Disable VMX if it is supported and enabled on the current CPU
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|  */
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| static inline void cpu_emergency_vmxoff(void)
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| {
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| 	if (cpu_has_vmx())
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| 		__cpu_emergency_vmxoff();
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| }
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| 
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| 
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| 
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| 
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| /*
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|  * SVM functions:
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|  */
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| 
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| /** Check if the CPU has SVM support
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|  *
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|  * You can use the 'msg' arg to get a message describing the problem,
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|  * if the function returns zero. Simply pass NULL if you are not interested
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|  * on the messages; gcc should take care of not generating code for
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|  * the messages on this case.
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|  */
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| static inline int cpu_has_svm(const char **msg)
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| {
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| 	uint32_t eax, ebx, ecx, edx;
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| 
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| 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
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| 		if (msg)
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| 			*msg = "not amd";
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| 		return 0;
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| 	}
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| 
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| 	cpuid(0x80000000, &eax, &ebx, &ecx, &edx);
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| 	if (eax < SVM_CPUID_FUNC) {
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| 		if (msg)
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| 			*msg = "can't execute cpuid_8000000a";
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| 		return 0;
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| 	}
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| 
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| 	cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
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| 	if (!(ecx & (1 << SVM_CPUID_FEATURE_SHIFT))) {
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| 		if (msg)
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| 			*msg = "svm not available";
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| 		return 0;
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| 	}
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| 	return 1;
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| }
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| 
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| 
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| /** Disable SVM on the current CPU
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|  *
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|  * You should call this only if cpu_has_svm() returned true.
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|  */
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| static inline void cpu_svm_disable(void)
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| {
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| 	uint64_t efer;
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| 
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| 	wrmsrl(MSR_VM_HSAVE_PA, 0);
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| 	rdmsrl(MSR_EFER, efer);
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| 	wrmsrl(MSR_EFER, efer & ~EFER_SVME);
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| }
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| 
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| /** Makes sure SVM is disabled, if it is supported on the CPU
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|  */
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| static inline void cpu_emergency_svm_disable(void)
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| {
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| 	if (cpu_has_svm(NULL))
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| 		cpu_svm_disable();
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| }
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| 
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| #endif /* _ASM_X86_VIRTEX_H */
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