LXR linux/arch/x86/include/asm/kvm

   1#ifndef _ASM_X86_KVM_PARA_H
   2#define _ASM_X86_KVM_PARA_H
   3
   4#include <linux/types.h>
   5
   6/* This CPUID returns the signature 'KVMKVMKVM' in ebx, ecx, and edx.  It
   7 * should be used to determine that a VM is running under KVM.
   8 */
   9#define KVM_CPUID_SIGNATURE     0x40000000
  10
  11/* This CPUID returns a feature bitmap in eax.  Before enabling a particular
  12 * paravirtualization, the appropriate feature bit should be checked.
  13 */
  14#define KVM_CPUID_FEATURES      0x40000001
  15#define KVM_FEATURE_CLOCKSOURCE         0
  16#define KVM_FEATURE_NOP_IO_DELAY        1
  17#define KVM_FEATURE_MMU_OP              2
  18
  19#define MSR_KVM_WALL_CLOCK  0x11
  20#define MSR_KVM_SYSTEM_TIME 0x12
  21
  22#define KVM_MAX_MMU_OP_BATCH           32
  23
  24/* Operations for KVM_HC_MMU_OP */
  25#define KVM_MMU_OP_WRITE_PTE            1
  26#define KVM_MMU_OP_FLUSH_TLB            2
  27#define KVM_MMU_OP_RELEASE_PT           3
  28
  29/* Payload for KVM_HC_MMU_OP */
  30struct kvm_mmu_op_header {
  31        __u32 op;
  32        __u32 pad;
  33};
  34
  35struct kvm_mmu_op_write_pte {
  36        struct kvm_mmu_op_header header;
  37        __u64 pte_phys;
  38        __u64 pte_val;
  39};
  40
  41struct kvm_mmu_op_flush_tlb {
  42        struct kvm_mmu_op_header header;
  43};
  44
  45struct kvm_mmu_op_release_pt {
  46        struct kvm_mmu_op_header header;
  47        __u64 pt_phys;
  48};
  49
  50#ifdef __KERNEL__
  51#include <asm/processor.h>
  52
  53extern void kvmclock_init(void);
  54
  55
  56/* This instruction is vmcall.  On non-VT architectures, it will generate a
  57 * trap that we will then rewrite to the appropriate instruction.
  58 */
  59#define KVM_HYPERCALL ".byte 0x0f,0x01,0xc1"
  60
  61/* For KVM hypercalls, a three-byte sequence of either the vmrun or the vmmrun
  62 * instruction.  The hypervisor may replace it with something else but only the
  63 * instructions are guaranteed to be supported.
  64 *
  65 * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
  66 * The hypercall number should be placed in rax and the return value will be
  67 * placed in rax.  No other registers will be clobbered unless explicited
  68 * noted by the particular hypercall.
  69 */
  70
  71static inline long kvm_hypercall0(unsigned int nr)
  72{
  73        long ret;
  74        asm volatile(KVM_HYPERCALL
  75                     : "=a"(ret)
  76                     : "a"(nr)
  77                     : "memory");
  78        return ret;
  79}
  80
  81static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
  82{
  83        long ret;
  84        asm volatile(KVM_HYPERCALL
  85                     : "=a"(ret)
  86                     : "a"(nr), "b"(p1)
  87                     : "memory");
  88        return ret;
  89}
  90
  91static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
  92                                  unsigned long p2)
  93{
  94        long ret;
  95        asm volatile(KVM_HYPERCALL
  96                     : "=a"(ret)
  97                     : "a"(nr), "b"(p1), "c"(p2)
  98                     : "memory");
  99        return ret;
 100}
 101
 102static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
 103                                  unsigned long p2, unsigned long p3)
 104{
 105        long ret;
 106        asm volatile(KVM_HYPERCALL
 107                     : "=a"(ret)
 108                     : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
 109                     : "memory");
 110        return ret;
 111}
 112
 113static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
 114                                  unsigned long p2, unsigned long p3,
 115                                  unsigned long p4)
 116{
 117        long ret;
 118        asm volatile(KVM_HYPERCALL
 119                     : "=a"(ret)
 120                     : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
 121                     : "memory");
 122        return ret;
 123}
 124
 125static inline int kvm_para_available(void)
 126{
 127        unsigned int eax, ebx, ecx, edx;
 128        char signature[13];
 129
 130        cpuid(KVM_CPUID_SIGNATURE, &eax, &ebx, &ecx, &edx);
 131        memcpy(signature + 0, &ebx, 4);
 132        memcpy(signature + 4, &ecx, 4);
 133        memcpy(signature + 8, &edx, 4);
 134        signature[12] = 0;
 135
 136        if (strcmp(signature, "KVMKVMKVM") == 0)
 137                return 1;
 138
 139        return 0;
 140}
 141
 142static inline unsigned int kvm_arch_para_features(void)
 143{
 144        return cpuid_eax(KVM_CPUID_FEATURES);
 145}
 146
 147#endif
 148
 149#endif /* _ASM_X86_KVM_PARA_H */
 150