[PATCH v3 10/23] KVM: x86/mmu: Use common code to free kvm_mmu_page structs

From: David Matlack <dmatlack@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marc Zyngier <maz@kernel.org>,
	Huacai Chen <chenhuacai@kernel.org>,
	Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
	Anup Patel <anup@brainfault.org>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Sean Christopherson <seanjc@google.com>,
	Andrew Jones <drjones@redhat.com>,
	Ben Gardon <bgardon@google.com>, Peter Xu <peterx@redhat.com>,
	maciej.szmigiero@oracle.com,
	"moderated list:KERNEL VIRTUAL MACHINE FOR ARM64 (KVM/arm64)" 
	<kvmarm@lists.cs.columbia.edu>,
	"open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" 
	<linux-mips@vger.kernel.org>,
	"open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" 
	<kvm@vger.kernel.org>,
	"open list:KERNEL VIRTUAL MACHINE FOR RISC-V (KVM/riscv)" 
	<kvm-riscv@lists.infradead.org>,
	Peter Feiner <pfeiner@google.com>,
	David Matlack <dmatlack@google.com>
Subject: [PATCH v3 10/23] KVM: x86/mmu: Use common code to free kvm_mmu_page structs
Date: Fri,  1 Apr 2022 17:55:41 +0000	[thread overview]
Message-ID: <20220401175554.1931568-11-dmatlack@google.com> (raw)
In-Reply-To: <20220401175554.1931568-1-dmatlack@google.com>

Use a common function to free kvm_mmu_page structs in the TDP MMU and
the shadow MMU. This reduces the amount of duplicate code and is needed
in subsequent commits that allocate and free kvm_mmu_pages for eager
page splitting. Keep tdp_mmu_free_sp() as a wrapper to mirror
tdp_mmu_alloc_sp().

No functional change intended.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/kvm/mmu/mmu.c          | 8 ++++----
 arch/x86/kvm/mmu/mmu_internal.h | 2 ++
 arch/x86/kvm/mmu/tdp_mmu.c      | 3 +--
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 657c2a906c12..27996fdb0e7e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1669,11 +1669,8 @@ static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, long nr)
 	percpu_counter_add(&kvm_total_used_mmu_pages, nr);
 }
 
-static void kvm_mmu_free_shadow_page(struct kvm_mmu_page *sp)
+void kvm_mmu_free_shadow_page(struct kvm_mmu_page *sp)
 {
-	MMU_WARN_ON(!is_empty_shadow_page(sp->spt));
-	hlist_del(&sp->hash_link);
-	list_del(&sp->link);
 	free_page((unsigned long)sp->spt);
 	if (!sp->role.direct)
 		free_page((unsigned long)sp->gfns);
@@ -2518,6 +2515,9 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm,
 
 	list_for_each_entry_safe(sp, nsp, invalid_list, link) {
 		WARN_ON(!sp->role.invalid || sp->root_count);
+		MMU_WARN_ON(!is_empty_shadow_page(sp->spt));
+		hlist_del(&sp->hash_link);
+		list_del(&sp->link);
 		kvm_mmu_free_shadow_page(sp);
 	}
 }
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index a0648e7ddd33..5f91e4d07a95 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -173,4 +173,6 @@ void unaccount_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp);
 
 struct kvm_mmu_page *kvm_mmu_alloc_direct_sp_for_split(bool locked);
 
+void kvm_mmu_free_shadow_page(struct kvm_mmu_page *sp);
+
 #endif /* __KVM_X86_MMU_INTERNAL_H */
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 34e581bcaaf6..8b00c868405b 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -64,8 +64,7 @@ void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm)
 
 static void tdp_mmu_free_sp(struct kvm_mmu_page *sp)
 {
-	free_page((unsigned long)sp->spt);
-	kmem_cache_free(mmu_page_header_cache, sp);
+	kvm_mmu_free_shadow_page(sp);
 }
 
 /*
-- 
2.35.1.1094.g7c7d902a7c-goog

