[PATCH 05/22] KVM: arm64: nv: Pass an access descriptor for stage-2 walks

[Oliver Upton <oupton@kernel.org>]

Pass sufficient context to the stage-2 PTW such that access-dependent
features like FEAT_HAFDBS can determine the correct behavior of the
walk.

Signed-off-by: Oliver Upton <oupton@kernel.org>
---
 arch/arm64/include/asm/kvm_nested.h | 15 ++++++++++++++-
 arch/arm64/kvm/at.c                 | 23 +++++++++++++++++++----
 arch/arm64/kvm/mmu.c                | 16 +++++++++++++++-
 arch/arm64/kvm/nested.c             | 10 +++++-----
 4 files changed, 53 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h
index 7fe6fb56c187..71814c4aac3e 100644
--- a/arch/arm64/include/asm/kvm_nested.h
+++ b/arch/arm64/include/asm/kvm_nested.h
@@ -105,7 +105,20 @@ static inline bool kvm_has_xnx(struct kvm *kvm)
 		kvm_has_feat(kvm, ID_AA64MMFR1_EL1, XNX, IMP);
 }
 
-extern int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, phys_addr_t gipa,
+struct kvm_walk_access {
+	enum {
+		WALK_ACCESS_IFETCH,
+		WALK_ACCESS_LDST,
+		WALK_ACCESS_CMO,
+		WALK_ACCESS_AT,
+		WALK_ACCESS_S1PTW,
+	} type;
+
+	u64	ia;
+	bool	write;
+};
+
+extern int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, struct kvm_walk_access *access,
 			      struct kvm_s2_trans *result);
 extern int kvm_s2_handle_perm_fault(struct kvm_vcpu *vcpu,
 				    struct kvm_s2_trans *trans);
diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index 7a84495a2e6d..083014e9d86a 100644
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -483,7 +483,19 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
 		ipa = baddr | index;
 
 		if (wi->s2) {
-			ret = kvm_walk_nested_s2(vcpu, ipa, &s2_trans);
+			struct kvm_walk_access s2_access = {
+				.type	= WALK_ACCESS_S1PTW,
+				.ia	= ipa,
+
+				/*
+				 * R_JCXVS, stage-2 dirty state can be updated
+				 * for an S1PTW even if the stage-1 descriptor
+				 * isn't updated.
+				 */
+				.write	= wi->ha,
+			};
+
+			ret = kvm_walk_nested_s2(vcpu, &s2_access, &s2_trans);
 			if (ret == -EAGAIN)
 				return ret;
 
@@ -1597,8 +1609,9 @@ int __kvm_at_s1e2(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
 
 int __kvm_at_s12(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
 {
+	struct kvm_walk_access access = {};
 	struct kvm_s2_trans out = {};
-	u64 ipa, par;
+	u64 par;
 	bool write;
 	int ret;
 
@@ -1642,9 +1655,11 @@ int __kvm_at_s12(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
 		return 0;
 
 	/* Do the stage-2 translation */
-	ipa = (par & GENMASK_ULL(47, 12)) | (vaddr & GENMASK_ULL(11, 0));
+	access.type = WALK_ACCESS_AT;
+	access.ia = (par & GENMASK_ULL(47, 12)) | (vaddr & GENMASK_ULL(11, 0));
 	out.esr = 0;
-	ret = kvm_walk_nested_s2(vcpu, ipa, &out);
+
+	ret = kvm_walk_nested_s2(vcpu, &access, &out);
 	if (ret < 0)
 		return ret;
 
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index f35c4ce95473..88998195274b 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -2313,9 +2313,23 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
 	 */
 	if (kvm_is_nested_s2_mmu(vcpu->kvm,vcpu->arch.hw_mmu) &&
 	    vcpu->arch.hw_mmu->nested_stage2_enabled) {
+		struct kvm_walk_access access = {
+			.ia	= fault_ipa,
+		};
 		u32 esr;
 
-		ret = kvm_walk_nested_s2(vcpu, fault_ipa, &nested_trans);
+		if (kvm_vcpu_abt_iss1tw(vcpu))
+			access.type = WALK_ACCESS_S1PTW;
+		else if (is_iabt)
+			access.type = WALK_ACCESS_IFETCH;
+		else if (kvm_vcpu_dabt_is_cm(vcpu))
+			access.type = WALK_ACCESS_CMO;
+		else
+			access.type = WALK_ACCESS_LDST;
+
+		access.write = kvm_is_write_fault(vcpu);
+
+		ret = kvm_walk_nested_s2(vcpu, &access, &nested_trans);
 		if (ret == -EAGAIN) {
 			ret = 1;
 			goto out_unlock;
diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index dcc7d0cc7c95..c2fb7290f0c8 100644
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -280,7 +280,7 @@ static void compute_s2_permissions(struct kvm_vcpu *vcpu, struct s2_walk_info *w
  *
  * Must be called with the kvm->srcu read lock held
  */
-static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa,
+static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, struct kvm_walk_access *access,
 			      struct s2_walk_info *wi, struct kvm_s2_trans *out)
 {
 	int first_block_level, stride, input_size, base_lower_bound;
@@ -330,7 +330,7 @@ static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa,
 		phys_addr_t index;
 
 		addr_bottom = (3 - ws.level) * stride + wi->pgshift;
-		index = (ipa & GENMASK_ULL(addr_top, addr_bottom))
+		index = (access->ia & GENMASK_ULL(addr_top, addr_bottom))
 			>> (addr_bottom - 3);
 
 		ws.desc_pa = base_addr | index;
@@ -412,7 +412,7 @@ static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa,
 
 	/* Calculate and return the result */
 	out->output = (ws.desc & GENMASK_ULL(47, addr_bottom)) |
-		      (ipa & GENMASK_ULL(addr_bottom - 1, 0));
+		      (access->ia & GENMASK_ULL(addr_bottom - 1, 0));
 	out->block_size = 1UL << ((3 - ws.level) * stride + wi->pgshift);
 	compute_s2_permissions(vcpu, wi, &ws, out);
 	out->level = ws.level;
@@ -515,7 +515,7 @@ static void setup_s2_walk(struct kvm_vcpu *vcpu, struct s2_walk_info *wi)
 	wi->be = vcpu_read_sys_reg(vcpu, SCTLR_EL2) & SCTLR_ELx_EE;
 }
 
-int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, phys_addr_t gipa,
+int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, struct kvm_walk_access *access,
 		       struct kvm_s2_trans *result)
 {
 	struct s2_walk_info wi;
@@ -528,7 +528,7 @@ int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, phys_addr_t gipa,
 
 	setup_s2_walk(vcpu, &wi);
 
-	ret = walk_nested_s2_pgd(vcpu, gipa, &wi, result);
+	ret = walk_nested_s2_pgd(vcpu, access, &wi, result);
 	if (ret)
 		result->esr |= (kvm_vcpu_get_esr(vcpu) & ~ESR_ELx_FSC);
 
-- 
2.47.3