Commit 5f43238d authored by Christian Borntraeger's avatar Christian Borntraeger Committed by Avi Kivity

KVM: Per-architecture hypercall definitions

Currently kvm provides hypercalls only for x86* architectures. To
provide hypercall infrastructure for other kvm architectures I split
kvm_para.h into a generic header file and architecture specific
definitions.
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 8c392696
#ifndef __X86_KVM_PARA_H
#define __X86_KVM_PARA_H
/* This CPUID returns the signature 'KVMKVMKVM' in ebx, ecx, and edx. It
* should be used to determine that a VM is running under KVM.
*/
#define KVM_CPUID_SIGNATURE 0x40000000
/* This CPUID returns a feature bitmap in eax. Before enabling a particular
* paravirtualization, the appropriate feature bit should be checked.
*/
#define KVM_CPUID_FEATURES 0x40000001
#ifdef __KERNEL__
#include <asm/processor.h>
/* This instruction is vmcall. On non-VT architectures, it will generate a
* trap that we will then rewrite to the appropriate instruction.
*/
#define KVM_HYPERCALL ".byte 0x0f,0x01,0xc1"
/* For KVM hypercalls, a three-byte sequence of either the vmrun or the vmmrun
* 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 explicited
* noted by the particular hypercall.
*/
static inline long kvm_hypercall0(unsigned int nr)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr));
return ret;
}
static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1));
return ret;
}
static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
unsigned long p2)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2));
return ret;
}
static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3));
return ret;
}
static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3,
unsigned long p4)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4));
return ret;
}
static inline int kvm_para_available(void)
{
unsigned int eax, ebx, ecx, edx;
char signature[13];
cpuid(KVM_CPUID_SIGNATURE, &eax, &ebx, &ecx, &edx);
memcpy(signature + 0, &ebx, 4);
memcpy(signature + 4, &ecx, 4);
memcpy(signature + 8, &edx, 4);
signature[12] = 0;
if (strcmp(signature, "KVMKVMKVM") == 0)
return 1;
return 0;
}
static inline unsigned int kvm_arch_para_features(void)
{
return cpuid_eax(KVM_CPUID_FEATURES);
}
#endif
#endif
#ifndef __LINUX_KVM_PARA_H #ifndef __LINUX_KVM_PARA_H
#define __LINUX_KVM_PARA_H #define __LINUX_KVM_PARA_H
/* This CPUID returns the signature 'KVMKVMKVM' in ebx, ecx, and edx. It /*
* should be used to determine that a VM is running under KVM. * This header file provides a method for making a hypercall to the host
* Architectures should define:
* - kvm_hypercall0, kvm_hypercall1...
* - kvm_arch_para_features
* - kvm_para_available
*/ */
#define KVM_CPUID_SIGNATURE 0x40000000
/* This CPUID returns a feature bitmap in eax. Before enabling a particular
* paravirtualization, the appropriate feature bit should be checked.
*/
#define KVM_CPUID_FEATURES 0x40000001
/* Return values for hypercalls */ /* Return values for hypercalls */
#define KVM_ENOSYS 1000 #define KVM_ENOSYS 1000
#ifdef __KERNEL__ #ifdef __KERNEL__
#include <asm/processor.h> /*
* hypercalls use architecture specific
/* This instruction is vmcall. On non-VT architectures, it will generate a
* trap that we will then rewrite to the appropriate instruction.
*/
#define KVM_HYPERCALL ".byte 0x0f,0x01,0xc1"
/* For KVM hypercalls, a three-byte sequence of either the vmrun or the vmmrun
* 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 explicited
* noted by the particular hypercall.
*/ */
#include <asm/kvm_para.h>
static inline long kvm_hypercall0(unsigned int nr)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr));
return ret;
}
static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1));
return ret;
}
static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
unsigned long p2)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2));
return ret;
}
static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3));
return ret;
}
static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3,
unsigned long p4)
{
long ret;
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4));
return ret;
}
static inline int kvm_para_available(void)
{
unsigned int eax, ebx, ecx, edx;
char signature[13];
cpuid(KVM_CPUID_SIGNATURE, &eax, &ebx, &ecx, &edx);
memcpy(signature + 0, &ebx, 4);
memcpy(signature + 4, &ecx, 4);
memcpy(signature + 8, &edx, 4);
signature[12] = 0;
if (strcmp(signature, "KVMKVMKVM") == 0)
return 1;
return 0;
}
static inline int kvm_para_has_feature(unsigned int feature) static inline int kvm_para_has_feature(unsigned int feature)
{ {
if (cpuid_eax(KVM_CPUID_FEATURES) & (1UL << feature)) if (kvm_arch_para_features() & (1UL << feature))
return 1; return 1;
return 0; return 0;
} }
#endif /* __KERNEL__ */
#endif /* __LINUX_KVM_PARA_H */
#endif
#endif
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