KVM: x86/mmu: Rename pte_list_{destroy,remove}() to show they zap SPTEs

[ Upstream commit 9202aee ]

Rename pte_list_remove() and pte_list_destroy() to kvm_zap_one_rmap_spte()
and kvm_zap_all_rmap_sptes() respectively to document that (a) they zap
SPTEs and (b) to better document how they differ (remove vs. destroy does
not exactly scream "one vs. all").

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220715224226.3749507-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd528 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: sean-jc

arch/x86/kvm/mmu/mmu.c

@@ -999,15 +999,16 @@ static void __pte_list_remove(u64 *spte, struct kvm_rmap_head *rmap_head)
 	}
 }
 
-static void pte_list_remove(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
-			    u64 *sptep)
+static void kvm_zap_one_rmap_spte(struct kvm *kvm,
+				  struct kvm_rmap_head *rmap_head, u64 *sptep)
 {
 	mmu_spte_clear_track_bits(kvm, sptep);
 	__pte_list_remove(sptep, rmap_head);
 }
 
-/* Return true if rmap existed, false otherwise */
-static bool pte_list_destroy(struct kvm *kvm, struct kvm_rmap_head *rmap_head)
+/* Return true if at least one SPTE was zapped, false otherwise */
+static bool kvm_zap_all_rmap_sptes(struct kvm *kvm,
+				   struct kvm_rmap_head *rmap_head)
 {
 	struct pte_list_desc *desc, *next;
 	int i;
@@ -1434,7 +1435,7 @@ static bool rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn)
 static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
 			  const struct kvm_memory_slot *slot)
 {
-	return pte_list_destroy(kvm, rmap_head);
+	return kvm_zap_all_rmap_sptes(kvm, rmap_head);
 }
 
 static bool kvm_unmap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
@@ -1465,7 +1466,7 @@ static bool kvm_set_pte_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
 		need_flush = 1;
 
 		if (pte_write(pte)) {
-			pte_list_remove(kvm, rmap_head, sptep);
+			kvm_zap_one_rmap_spte(kvm, rmap_head, sptep);
 			goto restart;
 		} else {
 			new_spte = kvm_mmu_changed_pte_notifier_make_spte(
@@ -1639,7 +1640,7 @@ static void rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
 	rmap_count = pte_list_add(vcpu, spte, rmap_head);
 
 	if (rmap_count > RMAP_RECYCLE_THRESHOLD) {
-		pte_list_destroy(vcpu->kvm, rmap_head);
+		kvm_zap_all_rmap_sptes(vcpu->kvm, rmap_head);
 		kvm_flush_remote_tlbs_with_address(
 				vcpu->kvm, sp->gfn, KVM_PAGES_PER_HPAGE(sp->role.level));
 	}
@@ -5873,7 +5874,7 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
 		    !kvm_is_reserved_pfn(pfn) &&
 		    sp->role.level < kvm_mmu_max_mapping_level(kvm, slot, sp->gfn,
 							       pfn, PG_LEVEL_NUM)) {
-			pte_list_remove(kvm, rmap_head, sptep);
+			kvm_zap_one_rmap_spte(kvm, rmap_head, sptep);
 
 			if (kvm_available_flush_tlb_with_range())
 				kvm_flush_remote_tlbs_with_address(kvm, sp->gfn,