linux-kernel - [RFC PATCH v2 14/18] KVM: TDX: Fold tdx_sept_zap_private_spte() into tdx_sept_remove_private

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Message-ID: <20250829000618.351013-15-seanjc@google.com>
Date: Thu, 28 Aug 2025 17:06:14 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Ira Weiny <ira.weiny@...el.com>, Kai Huang <kai.huang@...el.com>, 
	Michael Roth <michael.roth@....com>, Yan Zhao <yan.y.zhao@...el.com>, 
	Vishal Annapurve <vannapurve@...gle.com>, Rick Edgecombe <rick.p.edgecombe@...el.com>, 
	Ackerley Tng <ackerleytng@...gle.com>
Subject: [RFC PATCH v2 14/18] KVM: TDX: Fold tdx_sept_zap_private_spte() into tdx_sept_remove_private_spte()

Do TDH_MEM_RANGE_BLOCK directly in tdx_sept_remove_private_spte() instead
of using a one-off helper now that the nr_premapped tracking is gone.

Opportunistically drop the WARN on hugepages, which was dead code (see the
KVM_BUG_ON() in tdx_sept_remove_private_spte()).

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/vmx/tdx.c | 41 +++++++++++------------------------------
 1 file changed, 11 insertions(+), 30 deletions(-)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 00c3dc376690..aa6d88629dae 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1682,33 +1682,6 @@ static int tdx_sept_link_private_spt(struct kvm *kvm, gfn_t gfn,
 	return 0;
 }
 
-static int tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn,
-				     enum pg_level level, struct page *page)
-{
-	int tdx_level = pg_level_to_tdx_sept_level(level);
-	struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
-	gpa_t gpa = gfn_to_gpa(gfn) & KVM_HPAGE_MASK(level);
-	u64 err, entry, level_state;
-
-	/* For now large page isn't supported yet. */
-	WARN_ON_ONCE(level != PG_LEVEL_4K);
-
-	err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state);
-
-	if (unlikely(tdx_operand_busy(err))) {
-		/* After no vCPUs enter, the second retry is expected to succeed */
-		tdx_no_vcpus_enter_start(kvm);
-		err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state);
-		tdx_no_vcpus_enter_stop(kvm);
-	}
-
-	if (KVM_BUG_ON(err, kvm)) {
-		pr_tdx_error_2(TDH_MEM_RANGE_BLOCK, err, entry, level_state);
-		return -EIO;
-	}
-	return 1;
-}
-
 /*
  * Ensure shared and private EPTs to be flushed on all vCPUs.
  * tdh_mem_track() is the only caller that increases TD epoch. An increase in
@@ -1789,7 +1762,6 @@ static void tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
 	struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
 	gpa_t gpa = gfn_to_gpa(gfn);
 	u64 err, entry, level_state;
-	int ret;
 
 	/*
 	 * HKID is released after all private pages have been removed, and set
@@ -1803,9 +1775,18 @@ static void tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
 	if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
 		return;
 
-	ret = tdx_sept_zap_private_spte(kvm, gfn, level, page);
-	if (ret <= 0)
+	err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state);
+	if (unlikely(tdx_operand_busy(err))) {
+		/* After no vCPUs enter, the second retry is expected to succeed */
+		tdx_no_vcpus_enter_start(kvm);
+		err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state);
+		tdx_no_vcpus_enter_stop(kvm);
+	}
+
+	if (KVM_BUG_ON(err, kvm)) {
+		pr_tdx_error_2(TDH_MEM_RANGE_BLOCK, err, entry, level_state);
 		return;
+	}
 
 	/*
 	 * TDX requires TLB tracking before dropping private page.  Do
-- 
2.51.0.318.gd7df087d1a-goog