KVM: PPC: e500: Use __kvm_faultin_pfn() to handle page faults

[ Upstream commit 419cfb983ca93e75e905794521afefcfa07988bb ]

Convert PPC e500 to use __kvm_faultin_pfn()+kvm_release_faultin_page(),
and continue the inexorable march towards the demise of
kvm_pfn_to_refcounted_page().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-55-seanjc@google.com>
Stable-dep-of: 87ecfdbc699c ("KVM: e500: always restore irqs")
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/powerpc/kvm/e500_mmu_host.c

@@ -322,6 +322,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 {
 	struct kvm_memory_slot *slot;
 	unsigned long pfn = 0; /* silence GCC warning */
+	struct page *page = NULL;
 	unsigned long hva;
 	int pfnmap = 0;
 	int tsize = BOOK3E_PAGESZ_4K;
@@ -443,7 +444,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 
 	if (likely(!pfnmap)) {
 		tsize_pages = 1UL << (tsize + 10 - PAGE_SHIFT);
-		pfn = gfn_to_pfn_memslot(slot, gfn);
+		pfn = __kvm_faultin_pfn(slot, gfn, FOLL_WRITE, NULL, &page);
 		if (is_error_noslot_pfn(pfn)) {
 			if (printk_ratelimit())
 				pr_err("%s: real page not found for gfn %lx\n",
@@ -488,8 +489,6 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 		}
 	}
 	writable = kvmppc_e500_ref_setup(ref, gtlbe, pfn, wimg);
-	if (writable)
-		kvm_set_pfn_dirty(pfn);
 
 	kvmppc_e500_setup_stlbe(&vcpu_e500->vcpu, gtlbe, tsize,
 				ref, gvaddr, stlbe);
@@ -498,8 +497,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 	kvmppc_mmu_flush_icache(pfn);
 
 out:
-	/* Drop refcount on page, so that mmu notifiers can clear it */
-	kvm_release_pfn_clean(pfn);
+	kvm_release_faultin_page(kvm, page, !!ret, writable);
 	spin_unlock(&kvm->mmu_lock);
 	return ret;
 }