linux-zen-server/arch/arm64/kvm/hyp/include/hyp/fault.h

76 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#ifndef __ARM64_KVM_HYP_FAULT_H__
#define __ARM64_KVM_HYP_FAULT_H__
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
#include <asm/kvm_mmu.h>
static inline bool __translate_far_to_hpfar(u64 far, u64 *hpfar)
{
u64 par, tmp;
/*
* Resolve the IPA the hard way using the guest VA.
*
* Stage-1 translation already validated the memory access
* rights. As such, we can use the EL1 translation regime, and
* don't have to distinguish between EL0 and EL1 access.
*
* We do need to save/restore PAR_EL1 though, as we haven't
* saved the guest context yet, and we may return early...
*/
par = read_sysreg_par();
if (!__kvm_at("s1e1r", far))
tmp = read_sysreg_par();
else
tmp = SYS_PAR_EL1_F; /* back to the guest */
write_sysreg(par, par_el1);
if (unlikely(tmp & SYS_PAR_EL1_F))
return false; /* Translation failed, back to guest */
/* Convert PAR to HPFAR format */
*hpfar = PAR_TO_HPFAR(tmp);
return true;
}
static inline bool __get_fault_info(u64 esr, struct kvm_vcpu_fault_info *fault)
{
u64 hpfar, far;
far = read_sysreg_el2(SYS_FAR);
/*
* The HPFAR can be invalid if the stage 2 fault did not
* happen during a stage 1 page table walk (the ESR_EL2.S1PTW
* bit is clear) and one of the two following cases are true:
* 1. The fault was due to a permission fault
* 2. The processor carries errata 834220
*
* Therefore, for all non S1PTW faults where we either have a
* permission fault or the errata workaround is enabled, we
* resolve the IPA using the AT instruction.
*/
if (!(esr & ESR_ELx_S1PTW) &&
(cpus_have_final_cap(ARM64_WORKAROUND_834220) ||
(esr & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_PERM)) {
if (!__translate_far_to_hpfar(far, &hpfar))
return false;
} else {
hpfar = read_sysreg(hpfar_el2);
}
fault->far_el2 = far;
fault->hpfar_el2 = hpfar;
return true;
}
#endif