[RFC PATCH v2 19/23] KVM: TDX: Pass down pfn to split_external_spt()

[Yan Zhao <yan.y.zhao@intel.com>]

From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>

Pass down pfn to kvm_x86_ops::split_external_spt(). It is required for
handling Dynamic PAMT in tdx_sept_split_private_spt().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
---
RFC v2:
- Pulled from
  git://git.kernel.org/pub/scm/linux/kernel/git/kas/linux.git tdx/dpamt-huge.
- Rebased on top of TDX huge page RFC v2 (Yan)
---
 arch/x86/include/asm/kvm_host.h | 3 ++-
 arch/x86/kvm/mmu/tdp_mmu.c      | 6 +++++-
 arch/x86/kvm/vmx/tdx.c          | 3 ++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 6cb5b422dd1d..6b6c46c27390 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1841,7 +1841,8 @@ struct kvm_x86_ops {
 
 	/* Split the external page table into smaller page tables */
 	int (*split_external_spt)(struct kvm *kvm, gfn_t gfn, enum pg_level level,
-				  void *external_spt, bool mmu_lock_shared);
+				  kvm_pfn_t pfn_for_gfn, void *external_spt,
+				  bool mmu_lock_shared);
 
 	bool (*has_wbinvd_exit)(void);
 
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 62a09a9655c3..eb758aaa4374 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -389,11 +389,15 @@ static int split_external_spt(struct kvm *kvm, gfn_t gfn, u64 old_spte,
 			      u64 new_spte, int level, bool shared)
 {
 	void *external_spt = get_external_spt(gfn, new_spte, level);
+	kvm_pfn_t pfn_for_gfn = spte_to_pfn(old_spte);
 	int ret;
 
 	KVM_BUG_ON(!external_spt, kvm);
 
-	ret = kvm_x86_call(split_external_spt)(kvm, gfn, level, external_spt, shared);
+	ret = kvm_x86_call(split_external_spt)(kvm, gfn, level,
+					       pfn_for_gfn, external_spt,
+					       shared);
+
 	return ret;
 }
 /**
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 71115058e5e6..24aa9aaad6d8 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1941,7 +1941,8 @@ static int tdx_spte_demote_private_spte(struct kvm *kvm, gfn_t gfn,
 }
 
 static int tdx_sept_split_private_spt(struct kvm *kvm, gfn_t gfn, enum pg_level level,
-				      void *private_spt, bool mmu_lock_shared)
+				      kvm_pfn_t pfn_for_gfn, void *private_spt,
+				      bool mmu_lock_shared)
 {
 	struct page *page = virt_to_page(private_spt);
 	int ret;
-- 
2.43.2