[PATCH v2 16/24] KVM: arm64: Provide I-cache invalidation by VA at EL2

From: Will Deacon <will@kernel.org>
To: kvmarm@lists.cs.columbia.edu
Cc: Marc Zyngier <maz@kernel.org>,
	kernel-team@android.com, kvm@vger.kernel.org,
	Andy Lutomirski <luto@amacapital.net>,
	linux-arm-kernel@lists.infradead.org,
	Michael Roth <michael.roth@amd.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Chao Peng <chao.p.peng@linux.intel.com>,
	Will Deacon <will@kernel.org>
Subject: [PATCH v2 16/24] KVM: arm64: Provide I-cache invalidation by VA at EL2
Date: Thu, 30 Jun 2022 14:57:39 +0100	[thread overview]
Message-ID: <20220630135747.26983-17-will@kernel.org> (raw)
In-Reply-To: <20220630135747.26983-1-will@kernel.org>

In preparation for handling cache maintenance of guest pages at EL2,
introduce an EL2 copy of icache_inval_pou() which will later be plumbed
into the stage-2 page-table cache maintenance callbacks.

Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/include/asm/kvm_hyp.h |  1 +
 arch/arm64/kernel/image-vars.h   |  3 ---
 arch/arm64/kvm/arm.c             |  1 +
 arch/arm64/kvm/hyp/nvhe/cache.S  | 11 +++++++++++
 arch/arm64/kvm/hyp/nvhe/pkvm.c   |  3 +++
 5 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index aa7fa2a08f06..fd99cf09972d 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -123,4 +123,5 @@ extern u64 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val);
 extern u64 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val);
 extern u64 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val);
 
+extern unsigned long kvm_nvhe_sym(__icache_flags);
 #endif /* __ARM64_KVM_HYP_H__ */
diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
index 241c86b67d01..4e3b6d618ac1 100644
--- a/arch/arm64/kernel/image-vars.h
+++ b/arch/arm64/kernel/image-vars.h
@@ -80,9 +80,6 @@ KVM_NVHE_ALIAS(nvhe_hyp_panic_handler);
 /* Vectors installed by hyp-init on reset HVC. */
 KVM_NVHE_ALIAS(__hyp_stub_vectors);
 
-/* Kernel symbol used by icache_is_vpipt(). */
-KVM_NVHE_ALIAS(__icache_flags);
-
 /* VMID bits set by the KVM VMID allocator */
 KVM_NVHE_ALIAS(kvm_arm_vmid_bits);
 
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index a2343640c73c..90e0e7f38bb5 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1901,6 +1901,7 @@ static void kvm_hyp_init_symbols(void)
 	kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
 	kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
 	kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
+	kvm_nvhe_sym(__icache_flags) = __icache_flags;
 }
 
 static int kvm_hyp_init_protection(u32 hyp_va_bits)
diff --git a/arch/arm64/kvm/hyp/nvhe/cache.S b/arch/arm64/kvm/hyp/nvhe/cache.S
index 0c367eb5f4e2..85936c17ae40 100644
--- a/arch/arm64/kvm/hyp/nvhe/cache.S
+++ b/arch/arm64/kvm/hyp/nvhe/cache.S
@@ -12,3 +12,14 @@ SYM_FUNC_START(__pi_dcache_clean_inval_poc)
 	ret
 SYM_FUNC_END(__pi_dcache_clean_inval_poc)
 SYM_FUNC_ALIAS(dcache_clean_inval_poc, __pi_dcache_clean_inval_poc)
+
+SYM_FUNC_START(__pi_icache_inval_pou)
+alternative_if ARM64_HAS_CACHE_DIC
+	isb
+	ret
+alternative_else_nop_endif
+
+	invalidate_icache_by_line x0, x1, x2, x3
+	ret
+SYM_FUNC_END(__pi_icache_inval_pou)
+SYM_FUNC_ALIAS(icache_inval_pou, __pi_icache_inval_pou)
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c
index 77aeb787670b..114c5565de7d 100644
--- a/arch/arm64/kvm/hyp/nvhe/pkvm.c
+++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c
@@ -12,6 +12,9 @@
 #include <nvhe/pkvm.h>
 #include <nvhe/trap_handler.h>
 
+/* Used by icache_is_vpipt(). */
+unsigned long __icache_flags;
+
 /*
  * Set trap register values based on features in ID_AA64PFR0.
  */
-- 
2.37.0.rc0.161.g10f37bed90-goog

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