arm64: KVM: Basic ESR_EL2 helpers and vcpu register access

Implements helpers for dealing with the EL2 syndrome register as
well as accessing the vcpu registers.
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

arch/arm64/include/asm/kvm_emulate.h

+/*
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Derived from arch/arm/include/kvm_emulate.h
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ARM64_KVM_EMULATE_H__
+#define __ARM64_KVM_EMULATE_H__
+
+#include <linux/kvm_host.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmio.h>
+#include <asm/ptrace.h>
+
+void kvm_inject_undefined(struct kvm_vcpu *vcpu);
+void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
+void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
+
+static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
+{
+	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pc;
+}
+
+static inline unsigned long *vcpu_elr_el1(const struct kvm_vcpu *vcpu)
+{
+	return (unsigned long *)&vcpu_gp_regs(vcpu)->elr_el1;
+}
+
+static inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
+{
+	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pstate;
+}
+
+static inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
+{
+	return false;	/* 32bit? Bahhh... */
+}
+
+static inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
+{
+	return true;	/* No conditionals on arm64 */
+}
+
+static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
+{
+	*vcpu_pc(vcpu) += 4;
+}
+
+static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline unsigned long *vcpu_reg(const struct kvm_vcpu *vcpu, u8 reg_num)
+{
+	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.regs[reg_num];
+}
+
+/* Get vcpu SPSR for current mode */
+static inline unsigned long *vcpu_spsr(const struct kvm_vcpu *vcpu)
+{
+	return (unsigned long *)&vcpu_gp_regs(vcpu)->spsr[KVM_SPSR_EL1];
+}
+
+static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
+{
+	u32 mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
+
+	return mode != PSR_MODE_EL0t;
+}
+
+static inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu)
+{
+	return vcpu->arch.fault.esr_el2;
+}
+
+static inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
+{
+	return vcpu->arch.fault.far_el2;
+}
+
+static inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
+{
+	return ((phys_addr_t)vcpu->arch.fault.hpfar_el2 & HPFAR_MASK) << 8;
+}
+
+static inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_ISV);
+}
+
+static inline bool kvm_vcpu_dabt_iswrite(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_WNR);
+}
+
+static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_SSE);
+}
+
+static inline int kvm_vcpu_dabt_get_rd(const struct kvm_vcpu *vcpu)
+{
+	return (kvm_vcpu_get_hsr(vcpu) & ESR_EL2_SRT_MASK) >> ESR_EL2_SRT_SHIFT;
+}
+
+static inline bool kvm_vcpu_dabt_isextabt(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_EA);
+}
+
+static inline bool kvm_vcpu_dabt_iss1tw(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_S1PTW);
+}
+
+static inline int kvm_vcpu_dabt_get_as(const struct kvm_vcpu *vcpu)
+{
+	return 1 << ((kvm_vcpu_get_hsr(vcpu) & ESR_EL2_SAS) >> ESR_EL2_SAS_SHIFT);
+}
+
+/* This one is not specific to Data Abort */
+static inline bool kvm_vcpu_trap_il_is32bit(const struct kvm_vcpu *vcpu)
+{
+	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_EL2_IL);
+}
+
+static inline u8 kvm_vcpu_trap_get_class(const struct kvm_vcpu *vcpu)
+{
+	return kvm_vcpu_get_hsr(vcpu) >> ESR_EL2_EC_SHIFT;
+}
+
+static inline bool kvm_vcpu_trap_is_iabt(const struct kvm_vcpu *vcpu)
+{
+	return kvm_vcpu_trap_get_class(vcpu) == ESR_EL2_EC_IABT;
+}
+
+static inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
+{
+	return kvm_vcpu_get_hsr(vcpu) & ESR_EL2_FSC_TYPE;
+}
+
+#endif /* __ARM64_KVM_EMULATE_H__ */