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>

1 files changed, 12 insertions, 93 deletions

diff --git a/include/linux/kvm_para.h b/include/linux/kvm_para.h
index cc5dfb433706..e4db25ffdb52 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.
- */
-#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.
+/*
+ * hypercalls use architecture specific
  */
-
-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