[PATCH 09/17] KVM: TDX: Add helper to handle mapping leaf SPTE into S-EPT

[Rick Edgecombe]

From: Sean Christopherson <seanjc@xxxxxxxxxx>

Add a helper, tdx_sept_map_leaf_spte(), to wrap and isolate PAGE.ADD and
PAGE.AUG operations, and thus complete tdx_sept_set_private_spte()'s
transition into a "dispatch" routine for setting/writing S-EPT entries.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
---
 arch/x86/kvm/vmx/tdx.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 92a846b91bac..361a75b42ae7 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1689,18 +1689,12 @@ static int tdx_sept_link_private_spt(struct kvm *kvm, gfn_t gfn,
 	return 0;
 }
 
-static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
-				     enum pg_level level, u64 mirror_spte)
+static int tdx_sept_map_leaf_spte(struct kvm *kvm, gfn_t gfn, enum pg_level level,
+				  u64 mirror_spte)
 {
 	struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
 	kvm_pfn_t pfn = spte_to_pfn(mirror_spte);
 
-	if (KVM_BUG_ON(!is_shadow_present_pte(mirror_spte), kvm))
-		return -EIO;
-
-	if (!is_last_spte(mirror_spte, level))
-		return tdx_sept_link_private_spt(kvm, gfn, level, mirror_spte);
-
 	/* TODO: handle large pages. */
 	if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
 		return -EIO;
@@ -1725,7 +1719,18 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
 	return tdx_mem_page_aug(kvm, gfn, level, pfn);
 }
 
+static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
+				     enum pg_level level, u64 mirror_spte)
+{
 
+	if (KVM_BUG_ON(!is_shadow_present_pte(mirror_spte), kvm))
+		return -EIO;
+
+	if (!is_last_spte(mirror_spte, level))
+		return tdx_sept_link_private_spt(kvm, gfn, level, mirror_spte);
+
+	return tdx_sept_map_leaf_spte(kvm, gfn, level, mirror_spte);
+}
 
 /*
  * Ensure shared and private EPTs to be flushed on all vCPUs.
-- 
2.53.0