arch/x86/include/asm/kvm_para.h

   1 #ifndef _ASM_X86_KVM_PARA_H
   2 #define _ASM_X86_KVM_PARA_H
   3
   4 #include <asm/processor.h>
   5 #include <asm/alternative.h>
   6 #include <uapi/asm/kvm_para.h>
   7
   8 extern void kvmclock_init(void);
   9 extern int kvm_register_clock(char *txt);
  10
  11 #ifdef CONFIG_KVM_GUEST
  12 bool kvm_check_and_clear_guest_paused(void);
  13 #else
  14 static inline bool kvm_check_and_clear_guest_paused(void)
  15 {
  16         return false;
  17 }
  18 #endif /* CONFIG_KVM_GUEST */
  19
  20 #ifdef CONFIG_DEBUG_RODATA
  21 #define KVM_HYPERCALL \
  22         ALTERNATIVE(".byte 0x0f,0x01,0xc1", ".byte 0x0f,0x01,0xd9", X86_FEATURE_VMMCALL)
  23 #else
  24 /* On AMD processors, vmcall will generate a trap that we will
  25  * then rewrite to the appropriate instruction.
  26  */
  27 #define KVM_HYPERCALL ".byte 0x0f,0x01,0xc1"
  28 #endif
  29
  30 /* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
  31  * instruction.  The hypervisor may replace it with something else but only the
  32  * instructions are guaranteed to be supported.
  33  *
  34  * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
  35  * The hypercall number should be placed in rax and the return value will be
  36  * placed in rax.  No other registers will be clobbered unless explicitly
  37  * noted by the particular hypercall.
  38  */
  39
  40 static inline long kvm_hypercall0(unsigned int nr)
  41 {
  42         long ret;
  43         asm volatile(KVM_HYPERCALL
  44                      : "=a"(ret)
  45                      : "a"(nr)
  46                      : "memory");
  47         return ret;
  48 }
  49
  50 static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
  51 {
  52         long ret;
  53         asm volatile(KVM_HYPERCALL
  54                      : "=a"(ret)
  55                      : "a"(nr), "b"(p1)
  56                      : "memory");
  57         return ret;
  58 }
  59
  60 static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
  61                                   unsigned long p2)
  62 {
  63         long ret;
  64         asm volatile(KVM_HYPERCALL
  65                      : "=a"(ret)
  66                      : "a"(nr), "b"(p1), "c"(p2)
  67                      : "memory");
  68         return ret;
  69 }
  70
  71 static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
  72                                   unsigned long p2, unsigned long p3)
  73 {
  74         long ret;
  75         asm volatile(KVM_HYPERCALL
  76                      : "=a"(ret)
  77                      : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
  78                      : "memory");
  79         return ret;
  80 }
  81
  82 static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
  83                                   unsigned long p2, unsigned long p3,
  84                                   unsigned long p4)
  85 {
  86         long ret;
  87         asm volatile(KVM_HYPERCALL
  88                      : "=a"(ret)
  89                      : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
  90                      : "memory");
  91         return ret;
  92 }
  93
  94 #ifdef CONFIG_KVM_GUEST
  95 bool kvm_para_available(void);
  96 unsigned int kvm_arch_para_features(void);
  97 void __init kvm_guest_init(void);
  98 void kvm_async_pf_task_wait(u32 token);
  99 void kvm_async_pf_task_wake(u32 token);
 100 u32 kvm_read_and_reset_pf_reason(void);
 101 extern void kvm_disable_steal_time(void);
 102
 103 #ifdef CONFIG_PARAVIRT_SPINLOCKS
 104 void __init kvm_spinlock_init(void);
 105 #else /* !CONFIG_PARAVIRT_SPINLOCKS */
 106 static inline void kvm_spinlock_init(void)
 107 {
 108 }
 109 #endif /* CONFIG_PARAVIRT_SPINLOCKS */
 110
 111 #else /* CONFIG_KVM_GUEST */
 112 #define kvm_guest_init() do {} while (0)
 113 #define kvm_async_pf_task_wait(T) do {} while(0)
 114 #define kvm_async_pf_task_wake(T) do {} while(0)
 115
 116 static inline bool kvm_para_available(void)
 117 {
 118         return false;
 119 }
 120
 121 static inline unsigned int kvm_arch_para_features(void)
 122 {
 123         return 0;
 124 }
 125
 126 static inline u32 kvm_read_and_reset_pf_reason(void)
 127 {
 128         return 0;
 129 }
 130
 131 static inline void kvm_disable_steal_time(void)
 132 {
 133         return;
 134 }
 135 #endif
 136
 137 #endif /* _ASM_X86_KVM_PARA_H */