| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* arch/arm64/include/asm/kvm_ptrauth.h: Guest/host ptrauth save/restore |
| * Copyright 2019 Arm Limited |
| * Authors: Mark Rutland <mark.rutland@arm.com> |
| * Amit Daniel Kachhap <amit.kachhap@arm.com> |
| */ |
| |
| #ifndef __ASM_KVM_PTRAUTH_H |
| #define __ASM_KVM_PTRAUTH_H |
| |
| #ifdef __ASSEMBLY__ |
| |
| #include <asm/sysreg.h> |
| |
| #ifdef CONFIG_ARM64_PTR_AUTH |
| |
| #define PTRAUTH_REG_OFFSET(x) (x - CPU_APIAKEYLO_EL1) |
| |
| /* |
| * CPU_AP*_EL1 values exceed immediate offset range (512) for stp |
| * instruction so below macros takes CPU_APIAKEYLO_EL1 as base and |
| * calculates the offset of the keys from this base to avoid an extra add |
| * instruction. These macros assumes the keys offsets follow the order of |
| * the sysreg enum in kvm_host.h. |
| */ |
| .macro ptrauth_save_state base, reg1, reg2 |
| mrs_s \reg1, SYS_APIAKEYLO_EL1 |
| mrs_s \reg2, SYS_APIAKEYHI_EL1 |
| stp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APIAKEYLO_EL1)] |
| mrs_s \reg1, SYS_APIBKEYLO_EL1 |
| mrs_s \reg2, SYS_APIBKEYHI_EL1 |
| stp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APIBKEYLO_EL1)] |
| mrs_s \reg1, SYS_APDAKEYLO_EL1 |
| mrs_s \reg2, SYS_APDAKEYHI_EL1 |
| stp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APDAKEYLO_EL1)] |
| mrs_s \reg1, SYS_APDBKEYLO_EL1 |
| mrs_s \reg2, SYS_APDBKEYHI_EL1 |
| stp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APDBKEYLO_EL1)] |
| mrs_s \reg1, SYS_APGAKEYLO_EL1 |
| mrs_s \reg2, SYS_APGAKEYHI_EL1 |
| stp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APGAKEYLO_EL1)] |
| .endm |
| |
| .macro ptrauth_restore_state base, reg1, reg2 |
| ldp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APIAKEYLO_EL1)] |
| msr_s SYS_APIAKEYLO_EL1, \reg1 |
| msr_s SYS_APIAKEYHI_EL1, \reg2 |
| ldp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APIBKEYLO_EL1)] |
| msr_s SYS_APIBKEYLO_EL1, \reg1 |
| msr_s SYS_APIBKEYHI_EL1, \reg2 |
| ldp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APDAKEYLO_EL1)] |
| msr_s SYS_APDAKEYLO_EL1, \reg1 |
| msr_s SYS_APDAKEYHI_EL1, \reg2 |
| ldp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APDBKEYLO_EL1)] |
| msr_s SYS_APDBKEYLO_EL1, \reg1 |
| msr_s SYS_APDBKEYHI_EL1, \reg2 |
| ldp \reg1, \reg2, [\base, #PTRAUTH_REG_OFFSET(CPU_APGAKEYLO_EL1)] |
| msr_s SYS_APGAKEYLO_EL1, \reg1 |
| msr_s SYS_APGAKEYHI_EL1, \reg2 |
| .endm |
| |
| /* |
| * Both ptrauth_switch_to_guest and ptrauth_switch_to_hyp macros will |
| * check for the presence ARM64_HAS_ADDRESS_AUTH, which is defined as |
| * (ARM64_HAS_ADDRESS_AUTH_ARCH || ARM64_HAS_ADDRESS_AUTH_IMP_DEF) and |
| * then proceed ahead with the save/restore of Pointer Authentication |
| * key registers if enabled for the guest. |
| */ |
| .macro ptrauth_switch_to_guest g_ctxt, reg1, reg2, reg3 |
| alternative_if_not ARM64_HAS_ADDRESS_AUTH |
| b .L__skip_switch\@ |
| alternative_else_nop_endif |
| mrs \reg1, hcr_el2 |
| and \reg1, \reg1, #(HCR_API | HCR_APK) |
| cbz \reg1, .L__skip_switch\@ |
| add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 |
| ptrauth_restore_state \reg1, \reg2, \reg3 |
| .L__skip_switch\@: |
| .endm |
| |
| .macro ptrauth_switch_to_hyp g_ctxt, h_ctxt, reg1, reg2, reg3 |
| alternative_if_not ARM64_HAS_ADDRESS_AUTH |
| b .L__skip_switch\@ |
| alternative_else_nop_endif |
| mrs \reg1, hcr_el2 |
| and \reg1, \reg1, #(HCR_API | HCR_APK) |
| cbz \reg1, .L__skip_switch\@ |
| add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 |
| ptrauth_save_state \reg1, \reg2, \reg3 |
| add \reg1, \h_ctxt, #CPU_APIAKEYLO_EL1 |
| ptrauth_restore_state \reg1, \reg2, \reg3 |
| isb |
| .L__skip_switch\@: |
| .endm |
| |
| #else /* !CONFIG_ARM64_PTR_AUTH */ |
| .macro ptrauth_switch_to_guest g_ctxt, reg1, reg2, reg3 |
| .endm |
| .macro ptrauth_switch_to_hyp g_ctxt, h_ctxt, reg1, reg2, reg3 |
| .endm |
| #endif /* CONFIG_ARM64_PTR_AUTH */ |
| #endif /* __ASSEMBLY__ */ |
| #endif /* __ASM_KVM_PTRAUTH_H */ |
