arch/x86/include/asm/kvm_para.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_KVM_PARA_H
   3 #define _ASM_X86_KVM_PARA_H
   4
   5 #include <asm/processor.h>
   6 #include <asm/alternative.h>
   7 #include <uapi/asm/kvm_para.h>
   8
   9 extern void kvmclock_init(void);
  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 #define KVM_HYPERCALL \
  21         ALTERNATIVE(".byte 0x0f,0x01,0xc1", ".byte 0x0f,0x01,0xd9", X86_FEATURE_VMMCALL)
  22
  23 /* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
  24  * instruction.  The hypervisor may replace it with something else but only the
  25  * instructions are guaranteed to be supported.
  26  *
  27  * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
  28  * The hypercall number should be placed in rax and the return value will be
  29  * placed in rax.  No other registers will be clobbered unless explicitly
  30  * noted by the particular hypercall.
  31  */
  32
  33 static inline long kvm_hypercall0(unsigned int nr)
  34 {
  35         long ret;
  36         asm volatile(KVM_HYPERCALL
  37                      : "=a"(ret)
  38                      : "a"(nr)
  39                      : "memory");
  40         return ret;
  41 }
  42
  43 static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
  44 {
  45         long ret;
  46         asm volatile(KVM_HYPERCALL
  47                      : "=a"(ret)
  48                      : "a"(nr), "b"(p1)
  49                      : "memory");
  50         return ret;
  51 }
  52
  53 static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
  54                                   unsigned long p2)
  55 {
  56         long ret;
  57         asm volatile(KVM_HYPERCALL
  58                      : "=a"(ret)
  59                      : "a"(nr), "b"(p1), "c"(p2)
  60                      : "memory");
  61         return ret;
  62 }
  63
  64 static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
  65                                   unsigned long p2, unsigned long p3)
  66 {
  67         long ret;
  68         asm volatile(KVM_HYPERCALL
  69                      : "=a"(ret)
  70                      : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
  71                      : "memory");
  72         return ret;
  73 }
  74
  75 static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
  76                                   unsigned long p2, unsigned long p3,
  77                                   unsigned long p4)
  78 {
  79         long ret;
  80         asm volatile(KVM_HYPERCALL
  81                      : "=a"(ret)
  82                      : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
  83                      : "memory");
  84         return ret;
  85 }
  86
  87 #ifdef CONFIG_KVM_GUEST
  88 bool kvm_para_available(void);
  89 unsigned int kvm_arch_para_features(void);
  90 unsigned int kvm_arch_para_hints(void);
  91 void kvm_async_pf_task_wait(u32 token, int interrupt_kernel);
  92 void kvm_async_pf_task_wake(u32 token);
  93 u32 kvm_read_and_reset_pf_reason(void);
  94 extern void kvm_disable_steal_time(void);
  95
  96 #ifdef CONFIG_PARAVIRT_SPINLOCKS
  97 void __init kvm_spinlock_init(void);
  98 #else /* !CONFIG_PARAVIRT_SPINLOCKS */
  99 static inline void kvm_spinlock_init(void)
 100 {
 101 }
 102 #endif /* CONFIG_PARAVIRT_SPINLOCKS */
 103
 104 #else /* CONFIG_KVM_GUEST */
 105 #define kvm_async_pf_task_wait(T, I) do {} while(0)
 106 #define kvm_async_pf_task_wake(T) do {} while(0)
 107
 108 static inline bool kvm_para_available(void)
 109 {
 110         return false;
 111 }
 112
 113 static inline unsigned int kvm_arch_para_features(void)
 114 {
 115         return 0;
 116 }
 117
 118 static inline unsigned int kvm_arch_para_hints(void)
 119 {
 120         return 0;
 121 }
 122
 123 static inline u32 kvm_read_and_reset_pf_reason(void)
 124 {
 125         return 0;
 126 }
 127
 128 static inline void kvm_disable_steal_time(void)
 129 {
 130         return;
 131 }
 132 #endif
 133
 134 #endif /* _ASM_X86_KVM_PARA_H */