[PATCH v2 10/16] KVM: arm64: nv: Handle TLBI IPAS2E1{,IS} operations

[Marc Zyngier]

TLBI IPAS2E1* are the last class of TLBI instructions we need
to handle. For each matching S2 MMU context, we invalidate a
range corresponding to the largest possible mapping for that
context.

At this stage, we don't handle TTL, which means we are likely
over-invalidating. Further patches will aim at making this
a bit better.

Co-developed-by: Jintack Lim <jintack.lim at linaro.org>
Co-developed-by: Christoffer Dall <christoffer.dall at arm.com>
Signed-off-by: Jintack Lim <jintack.lim at linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall at arm.com>
Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/kvm/sys_regs.c | 96 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index d8d6380b7c66..06963f1d206e 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2780,6 +2780,31 @@ static bool handle_alle1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 	return true;
 }
 
+static bool kvm_supported_tlbi_ipas2_op(struct kvm_vcpu *vpcu, u32 instr)
+{
+	struct kvm *kvm = vpcu->kvm;
+	u8 CRm = sys_reg_CRm(instr);
+	u8 Op2 = sys_reg_Op2(instr);
+
+	if (sys_reg_CRn(instr) == TLBI_CRn_nXS &&
+	    !kvm_has_feat(kvm, ID_AA64ISAR1_EL1, XS, IMP))
+		return false;
+
+	if (CRm == TLBI_CRm_IPAIS && (Op2 == 2 || Op2 == 6) &&
+	    !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, RANGE))
+		return false;
+
+	if (CRm == TLBI_CRm_IPAONS && (Op2 == 0 || Op2 == 4) &&
+	    !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, OS))
+		return false;
+
+	if (CRm == TLBI_CRm_IPAONS && (Op2 == 3 || Op2 == 7) &&
+	    !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, RANGE))
+		return false;
+
+	return true;
+}
+
 /* Only defined here as this is an internal "abstraction" */
 union tlbi_info {
 	struct {
@@ -2829,6 +2854,72 @@ static bool handle_vmalls12e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 	return true;
 }
 
+static void s2_mmu_unmap_ipa(struct kvm_s2_mmu *mmu,
+			     const union tlbi_info *info)
+{
+	unsigned long max_size;
+	u64 base_addr;
+
+	/*
+	 * We drop a number of things from the supplied value:
+	 *
+	 * - NS bit: we're non-secure only.
+	 *
+	 * - TTL field: We already have the granule size from the
+	 *   VTCR_EL2.TG0 field, and the level is only relevant to the
+	 *   guest's S2PT.
+	 *
+	 * - IPA[51:48]: We don't support 52bit IPA just yet...
+	 *
+	 * And of course, adjust the IPA to be on an actual address.
+	 */
+	base_addr = (info->ipa.addr & GENMASK_ULL(35, 0)) << 12;
+
+	/* Compute the maximum extent of the invalidation */
+	switch (mmu->tlb_vtcr & VTCR_EL2_TG0_MASK) {
+	case VTCR_EL2_TG0_4K:
+		max_size = SZ_1G;
+		break;
+	case VTCR_EL2_TG0_16K:
+		max_size = SZ_32M;
+		break;
+	case VTCR_EL2_TG0_64K:
+	default:	    /* IMPDEF: treat any other value as 64k */
+		/*
+		 * No, we do not support 52bit IPA in nested yet. Once
+		 * we do, this should be 4TB.
+		 */
+		max_size = SZ_512M;
+		break;
+	}
+
+	base_addr &= ~(max_size - 1);
+
+	kvm_stage2_unmap_range(mmu, base_addr, max_size);
+}
+
+static bool handle_ipas2e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			     const struct sys_reg_desc *r)
+{
+	u32 sys_encoding = sys_insn(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2);
+	u64 vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+
+	if (!kvm_supported_tlbi_ipas2_op(vcpu, sys_encoding)) {
+		kvm_inject_undefined(vcpu);
+		return false;
+	}
+
+	kvm_s2_mmu_iterate_by_vmid(vcpu->kvm, get_vmid(vttbr),
+				   &(union tlbi_info) {
+					   .ipa = {
+						   .addr = p->regval,
+					   },
+				   },
+				   s2_mmu_unmap_ipa);
+
+	return true;
+}
+
 static void s2_mmu_tlbi_s1e1(struct kvm_s2_mmu *mmu,
 			     const union tlbi_info *info)
 {
@@ -2903,8 +2994,13 @@ static struct sys_reg_desc sys_insn_descs[] = {
 	SYS_INSN(TLBI_VALE1, handle_tlbi_el1),
 	SYS_INSN(TLBI_VAALE1, handle_tlbi_el1),
 
+	SYS_INSN(TLBI_IPAS2E1IS, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1IS, handle_ipas2e1is),
+
 	SYS_INSN(TLBI_ALLE1IS, handle_alle1is),
 	SYS_INSN(TLBI_VMALLS12E1IS, handle_vmalls12e1is),
+	SYS_INSN(TLBI_IPAS2E1, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1, handle_ipas2e1is),
 	SYS_INSN(TLBI_ALLE1, handle_alle1is),
 	SYS_INSN(TLBI_VMALLS12E1, handle_vmalls12e1is),
 };
-- 
2.39.2