diff mbox series

[v2,08/94] KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state

Message ID 20200211174938.27809-9-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series KVM: arm64: ARMv8.3/8.4 Nested Virtualization support | expand

Commit Message

Marc Zyngier Feb. 11, 2020, 5:48 p.m. UTC 
From: Christoffer Dall <christoffer.dall@arm.com>

When running a nested hypervisor we commonly have to figure out if
the VCPU mode is running in the context of a guest hypervisor or guest
guest, or just a normal guest.

Add convenient primitives for this.

Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_emulate.h | 55 ++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 688c63412cc2..9646ad7c2640 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -194,6 +194,61 @@  static inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
 		vcpu_gp_regs(vcpu)->regs.regs[reg_num] = val;
 }
 
+static inline bool vcpu_mode_el2_ctxt(const struct kvm_cpu_context *ctxt)
+{
+	unsigned long cpsr = ctxt->gp_regs.regs.pstate;
+
+	switch (cpsr & (PSR_MODE32_BIT | PSR_MODE_MASK)) {
+	case PSR_MODE_EL2h:
+	case PSR_MODE_EL2t:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static inline bool vcpu_mode_el2(const struct kvm_vcpu *vcpu)
+{
+	return vcpu_mode_el2_ctxt(&vcpu->arch.ctxt);
+}
+
+static inline bool __vcpu_el2_e2h_is_set(const struct kvm_cpu_context *ctxt)
+{
+	return ctxt->sys_regs[HCR_EL2] & HCR_E2H;
+}
+
+static inline bool vcpu_el2_e2h_is_set(const struct kvm_vcpu *vcpu)
+{
+	return __vcpu_el2_e2h_is_set(&vcpu->arch.ctxt);
+}
+
+static inline bool __vcpu_el2_tge_is_set(const struct kvm_cpu_context *ctxt)
+{
+	return ctxt->sys_regs[HCR_EL2] & HCR_TGE;
+}
+
+static inline bool vcpu_el2_tge_is_set(const struct kvm_vcpu *vcpu)
+{
+	return __vcpu_el2_tge_is_set(&vcpu->arch.ctxt);
+}
+
+static inline bool __is_hyp_ctxt(const struct kvm_cpu_context *ctxt)
+{
+	/*
+	 * We are in a hypervisor context if the vcpu mode is EL2 or
+	 * E2H and TGE bits are set. The latter means we are in the user space
+	 * of the VHE kernel. ARMv8.1 ARM describes this as 'InHost'
+	 */
+	return vcpu_mode_el2_ctxt(ctxt) ||
+		(__vcpu_el2_e2h_is_set(ctxt) && __vcpu_el2_tge_is_set(ctxt)) ||
+		WARN_ON(__vcpu_el2_tge_is_set(ctxt));
+}
+
+static inline bool is_hyp_ctxt(const struct kvm_vcpu *vcpu)
+{
+	return __is_hyp_ctxt(&vcpu->arch.ctxt);
+}
+
 static inline unsigned long vcpu_read_spsr(const struct kvm_vcpu *vcpu)
 {
 	if (vcpu_mode_is_32bit(vcpu))