[v19,073/130] KVM: x86: Add hooks in kvm_arch_vcpu_memory_mapping()

Commit Message

Isaku Yamahata Feb. 26, 2024, 8:26 a.m. UTC

From: Isaku Yamahata <[e-mail]>

In the case of TDX, the memory contents needs to be provided to be
encrypted when populating guest memory before running the guest.  Add hooks
in kvm_mmu_map_tdp_page() for KVM_MEMORY_MAPPING before/after calling
kvm_mmu_tdp_page().  TDX KVM will implement the hooks.

Signed-off-by: Isaku Yamahata <[e-mail]>
---
v19:
- newly added
---
 arch/x86/include/asm/kvm-x86-ops.h |  2 ++
 arch/x86/include/asm/kvm_host.h    |  5 +++++
 arch/x86/kvm/x86.c                 | 13 ++++++++++++-
 3 files changed, 19 insertions(+), 1 deletion(-)

Patch

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e1c75f8c1b25..fb3ae97c724e 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -151,6 +151,8 @@  KVM_X86_OP(vcpu_deliver_sipi_vector)
 KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons);
 KVM_X86_OP_OPTIONAL(get_untagged_addr)
 KVM_X86_OP_OPTIONAL_RET0(gmem_max_level)
+KVM_X86_OP_OPTIONAL(pre_memory_mapping);
+KVM_X86_OP_OPTIONAL(post_memory_mapping);
 
 #undef KVM_X86_OP
 #undef KVM_X86_OP_OPTIONAL
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bc0767c884f7..36694e784c27 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1839,6 +1839,11 @@  struct kvm_x86_ops {
 
 	int (*gmem_max_level)(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn,
 			      bool is_private, u8 *max_level);
+	int (*pre_memory_mapping)(struct kvm_vcpu *vcpu,
+				  struct kvm_memory_mapping *mapping,
+				  u64 *error_code, u8 *max_level);
+	void (*post_memory_mapping)(struct kvm_vcpu *vcpu,
+				    struct kvm_memory_mapping *mapping);
 };
 
 struct kvm_x86_nested_ops {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2bd4b7c8fa51..23ece956c816 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5826,10 +5826,21 @@  int kvm_arch_vcpu_memory_mapping(struct kvm_vcpu *vcpu,
 	u8 max_level = KVM_MAX_HUGEPAGE_LEVEL;
 	u64 error_code = PFERR_WRITE_MASK;
 	u8 goal_level = PG_LEVEL_4K;
-	int r;
+	int r = 0;
+
+	if (kvm_x86_ops.pre_memory_mapping)
+		r = static_call(kvm_x86_pre_memory_mapping)(vcpu, mapping, &error_code, &max_level);
+	else {
+		if (mapping->source)
+			r = -EINVAL;
+	}
+	if (r)
+		return r;
 
 	r = kvm_mmu_map_tdp_page(vcpu, gfn_to_gpa(mapping->base_gfn), error_code,
 				 max_level, &goal_level);
+	if (kvm_x86_ops.post_memory_mapping)
+		static_call(kvm_x86_post_memory_mapping)(vcpu, mapping);
 	if (r)
 		return r;