arch/arm64/kvm/hyp/include/hyp/adjust_pc.h

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Guest PC manipulation helpers
   4  *
   5  * Copyright (C) 2012,2013 - ARM Ltd
   6  * Copyright (C) 2020 - Google LLC
   7  * Author: Marc Zyngier <maz@kernel.org>
   8  */
   9
  10 #ifndef __ARM64_KVM_HYP_ADJUST_PC_H__
  11 #define __ARM64_KVM_HYP_ADJUST_PC_H__
  12
  13 #include <asm/kvm_emulate.h>
  14 #include <asm/kvm_host.h>
  15
  16 void kvm_inject_exception(struct kvm_vcpu *vcpu);
  17
  18 static inline void kvm_skip_instr(struct kvm_vcpu *vcpu)
  19 {
  20         if (vcpu_mode_is_32bit(vcpu)) {
  21                 kvm_skip_instr32(vcpu);
  22         } else {
  23                 *vcpu_pc(vcpu) += 4;
  24                 *vcpu_cpsr(vcpu) &= ~PSR_BTYPE_MASK;
  25         }
  26
  27         /* advance the singlestep state machine */
  28         *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
  29 }
  30
  31 /*
  32  * Skip an instruction which has been emulated at hyp while most guest sysregs
  33  * are live.
  34  */
  35 static inline void __kvm_skip_instr(struct kvm_vcpu *vcpu)
  36 {
  37         *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
  38         vcpu_gp_regs(vcpu)->pstate = read_sysreg_el2(SYS_SPSR);
  39
  40         kvm_skip_instr(vcpu);
  41
  42         write_sysreg_el2(vcpu_gp_regs(vcpu)->pstate, SYS_SPSR);
  43         write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
  44 }
  45
  46 /*
  47  * Adjust the guest PC on entry, depending on flags provided by EL1
  48  * for the purpose of emulation (MMIO, sysreg) or exception injection.
  49  */
  50 static inline void __adjust_pc(struct kvm_vcpu *vcpu)
  51 {
  52         if (vcpu->arch.flags & KVM_ARM64_PENDING_EXCEPTION) {
  53                 kvm_inject_exception(vcpu);
  54                 vcpu->arch.flags &= ~(KVM_ARM64_PENDING_EXCEPTION |
  55                                       KVM_ARM64_EXCEPT_MASK);
  56         } else  if (vcpu->arch.flags & KVM_ARM64_INCREMENT_PC) {
  57                 kvm_skip_instr(vcpu);
  58                 vcpu->arch.flags &= ~KVM_ARM64_INCREMENT_PC;
  59         }
  60 }
  61
  62 #endif