From: Anup Patel <apatel@ventanamicro.com>
To: Atish Patra <atish.patra@linux.dev>
Cc: Palmer Dabbelt <palmer@dabbelt.com>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Alexandre Ghiti <alex@ghiti.fr>,
	Andrew Jones <ajones@ventanamicro.com>,
	Anup Patel <anup@brainfault.org>,
	kvm@vger.kernel.org,
	kvm-riscv@lists.infradead.org,
	linux-riscv@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	Anup Patel <apatel@ventanamicro.com>,
	Atish Patra <atishp@rivosinc.com>
Subject: [PATCH v3 06/12] RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range()
Date: Wed, 18 Jun 2025 17:05:26 +0530
Message-ID: <20250618113532.471448-7-apatel@ventanamicro.com>
In-Reply-To: <20250618113532.471448-1-apatel@ventanamicro.com>
References: <20250618113532.471448-1-apatel@ventanamicro.com>
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The kvm_arch_flush_remote_tlbs_range() expected by KVM core can be
easily implemented for RISC-V using kvm_riscv_hfence_gvma_vmid_gpa()
hence provide it.

Also with kvm_arch_flush_remote_tlbs_range() available for RISC-V, the
mmu_wp_memory_region() can happily use kvm_flush_remote_tlbs_memslot()
instead of kvm_flush_remote_tlbs().

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/include/asm/kvm_host.h | 2 ++
 arch/riscv/kvm/mmu.c              | 2 +-
 arch/riscv/kvm/tlb.c              | 8 ++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index ff1f76d6f177..6162575e2177 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -43,6 +43,8 @@
 	KVM_ARCH_REQ_FLAGS(5, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
 #define KVM_REQ_STEAL_UPDATE		KVM_ARCH_REQ(6)
 
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE
+
 #define KVM_HEDELEG_DEFAULT		(BIT(EXC_INST_MISALIGNED) | \
 					 BIT(EXC_BREAKPOINT)      | \
 					 BIT(EXC_SYSCALL)         | \
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index 29f1bd853a66..a5387927a1c1 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -344,7 +344,7 @@ static void gstage_wp_memory_region(struct kvm *kvm, int slot)
 	spin_lock(&kvm->mmu_lock);
 	gstage_wp_range(kvm, start, end);
 	spin_unlock(&kvm->mmu_lock);
-	kvm_flush_remote_tlbs(kvm);
+	kvm_flush_remote_tlbs_memslot(kvm, memslot);
 }
 
 int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa,
diff --git a/arch/riscv/kvm/tlb.c b/arch/riscv/kvm/tlb.c
index da98ca801d31..f46a27658c2e 100644
--- a/arch/riscv/kvm/tlb.c
+++ b/arch/riscv/kvm/tlb.c
@@ -403,3 +403,11 @@ void kvm_riscv_hfence_vvma_all(struct kvm *kvm,
 	make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_VVMA_ALL,
 			    KVM_REQ_HFENCE_VVMA_ALL, NULL);
 }
+
+int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages)
+{
+	kvm_riscv_hfence_gvma_vmid_gpa(kvm, -1UL, 0,
+				       gfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT,
+				       PAGE_SHIFT);
+	return 0;
+}
-- 
2.43.0