arch/x86/include/asm/kvm_para.h

Source file repositories/reference/linux-study-clean/arch/x86/include/asm/kvm_para.h

File Facts

System
Linux kernel
Corpus path
arch/x86/include/asm/kvm_para.h
Extension
.h
Size
4141 bytes
Lines
178
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _ASM_X86_KVM_PARA_H
#define _ASM_X86_KVM_PARA_H

#include <asm/processor.h>
#include <asm/alternative.h>
#include <linux/interrupt.h>
#include <uapi/asm/kvm_para.h>

#include <asm/tdx.h>

#ifdef CONFIG_KVM_GUEST
bool kvm_check_and_clear_guest_paused(void);
#else
static inline bool kvm_check_and_clear_guest_paused(void)
{
	return false;
}
#endif /* CONFIG_KVM_GUEST */

#define KVM_HYPERCALL \
        ALTERNATIVE("vmcall", "vmmcall", X86_FEATURE_VMMCALL)

/* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
 * instruction.  The hypervisor may replace it with something else but only the
 * instructions are guaranteed to be supported.
 *
 * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
 * The hypercall number should be placed in rax and the return value will be
 * placed in rax.  No other registers will be clobbered unless explicitly
 * noted by the particular hypercall.
 */

static inline long kvm_hypercall0(unsigned int nr)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, 0, 0, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, 0, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
				  unsigned long p2)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, p2, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
				  unsigned long p2, unsigned long p3)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, p2, p3, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
		     : "memory");
	return ret;
}

Annotation

Implementation Notes