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: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/include/linux/kvm_para.h b/include/linux/kvm_para.h
index cc5dfb4..e4db25f 100644
--- a/include/linux/kvm_para.h
+++ b/include/linux/kvm_para.h
@@ -1,110 +1,29 @@
#ifndef __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 */
#define KVM_ENOSYS 1000
#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.
+/*
+ * hypercalls use architecture specific
*/
-#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;
-}
+#include <asm/kvm_para.h>
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 0;
}
+#endif /* __KERNEL__ */
+#endif /* __LINUX_KVM_PARA_H */
-#endif
-
-#endif