[PATCH v2 06/12] RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range()

From: Anup Patel
Date: Fri Jun 13 2025 - 02:59:46 EST


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().

Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
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