[PATCH v1 3/6] KVM: arm64: Move pkvm_mem_abort()

[Vincent Donnefort]

Move pkvm_mem_abort() below kvm_s2_fault_get_vma_info() so it can
resolve stage-2 fault VMA metadata without forward declarations.

No functional change intended.

Signed-off-by: Vincent Donnefort <vdonnefort at google.com>
---
 arch/arm64/kvm/mmu.c | 138 +++++++++++++++++++++----------------------
 1 file changed, 69 insertions(+), 69 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 9dfaf4f277b5..242f63066252 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1706,75 +1706,6 @@ struct kvm_s2_fault_vma_info {
 	bool		map_non_cacheable;
 };
 
-static int pkvm_mem_abort(const struct kvm_s2_fault_desc *s2fd)
-{
-	unsigned int flags = FOLL_HWPOISON | FOLL_LONGTERM | FOLL_WRITE;
-	struct kvm_vcpu *vcpu = s2fd->vcpu;
-	struct kvm_pgtable *pgt = vcpu->arch.hw_mmu->pgt;
-	struct mm_struct *mm = current->mm;
-	struct kvm *kvm = vcpu->kvm;
-	void *hyp_memcache;
-	struct page *page;
-	int ret;
-
-	hyp_memcache = get_mmu_memcache(vcpu);
-	ret = topup_mmu_memcache(vcpu, hyp_memcache);
-	if (ret)
-		return -ENOMEM;
-
-	ret = account_locked_vm(mm, 1, true);
-	if (ret)
-		return ret;
-
-	mmap_read_lock(mm);
-	ret = pin_user_pages(s2fd->hva, 1, flags, &page);
-	mmap_read_unlock(mm);
-
-	if (ret == -EHWPOISON) {
-		kvm_send_hwpoison_signal(s2fd->hva, PAGE_SHIFT);
-		ret = 0;
-		goto dec_account;
-	} else if (ret != 1) {
-		ret = -EFAULT;
-		goto dec_account;
-	} else if (!folio_test_swapbacked(page_folio(page))) {
-		/*
-		 * We really can't deal with page-cache pages returned by GUP
-		 * because (a) we may trigger writeback of a page for which we
-		 * no longer have access and (b) page_mkclean() won't find the
-		 * stage-2 mapping in the rmap so we can get out-of-whack with
-		 * the filesystem when marking the page dirty during unpinning
-		 * (see cc5095747edf ("ext4: don't BUG if someone dirty pages
-		 * without asking ext4 first")).
-		 *
-		 * Ideally we'd just restrict ourselves to anonymous pages, but
-		 * we also want to allow memfd (i.e. shmem) pages, so check for
-		 * pages backed by swap in the knowledge that the GUP pin will
-		 * prevent try_to_unmap() from succeeding.
-		 */
-		ret = -EIO;
-		goto unpin;
-	}
-
-	write_lock(&kvm->mmu_lock);
-	ret = pkvm_pgtable_stage2_map(pgt, s2fd->fault_ipa, PAGE_SIZE,
-				      page_to_phys(page), KVM_PGTABLE_PROT_RWX,
-				      hyp_memcache, 0);
-	write_unlock(&kvm->mmu_lock);
-	if (ret) {
-		if (ret == -EAGAIN)
-			ret = 0;
-		goto unpin;
-	}
-
-	return 0;
-unpin:
-	unpin_user_pages(&page, 1);
-dec_account:
-	account_locked_vm(mm, 1, false);
-	return ret;
-}
-
 static short kvm_s2_resolve_vma_size(const struct kvm_s2_fault_desc *s2fd,
 				     struct kvm_s2_fault_vma_info *s2vi,
 				     struct vm_area_struct *vma)
@@ -2235,6 +2166,75 @@ int kvm_handle_guest_sea(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
+static int pkvm_mem_abort(const struct kvm_s2_fault_desc *s2fd)
+{
+	unsigned int flags = FOLL_HWPOISON | FOLL_LONGTERM | FOLL_WRITE;
+	struct kvm_vcpu *vcpu = s2fd->vcpu;
+	struct kvm_pgtable *pgt = vcpu->arch.hw_mmu->pgt;
+	struct mm_struct *mm = current->mm;
+	struct kvm *kvm = vcpu->kvm;
+	void *hyp_memcache;
+	struct page *page;
+	int ret;
+
+	hyp_memcache = get_mmu_memcache(vcpu);
+	ret = topup_mmu_memcache(vcpu, hyp_memcache);
+	if (ret)
+		return -ENOMEM;
+
+	ret = account_locked_vm(mm, 1, true);
+	if (ret)
+		return ret;
+
+	mmap_read_lock(mm);
+	ret = pin_user_pages(s2fd->hva, 1, flags, &page);
+	mmap_read_unlock(mm);
+
+	if (ret == -EHWPOISON) {
+		kvm_send_hwpoison_signal(s2fd->hva, PAGE_SHIFT);
+		ret = 0;
+		goto dec_account;
+	} else if (ret != 1) {
+		ret = -EFAULT;
+		goto dec_account;
+	} else if (!folio_test_swapbacked(page_folio(page))) {
+		/*
+		 * We really can't deal with page-cache pages returned by GUP
+		 * because (a) we may trigger writeback of a page for which we
+		 * no longer have access and (b) page_mkclean() won't find the
+		 * stage-2 mapping in the rmap so we can get out-of-whack with
+		 * the filesystem when marking the page dirty during unpinning
+		 * (see cc5095747edf ("ext4: don't BUG if someone dirty pages
+		 * without asking ext4 first")).
+		 *
+		 * Ideally we'd just restrict ourselves to anonymous pages, but
+		 * we also want to allow memfd (i.e. shmem) pages, so check for
+		 * pages backed by swap in the knowledge that the GUP pin will
+		 * prevent try_to_unmap() from succeeding.
+		 */
+		ret = -EIO;
+		goto unpin;
+	}
+
+	write_lock(&kvm->mmu_lock);
+	ret = pkvm_pgtable_stage2_map(pgt, s2fd->fault_ipa, PAGE_SIZE,
+				      page_to_phys(page), KVM_PGTABLE_PROT_RWX,
+				      hyp_memcache, 0);
+	write_unlock(&kvm->mmu_lock);
+	if (ret) {
+		if (ret == -EAGAIN)
+			ret = 0;
+		goto unpin;
+	}
+
+	return 0;
+unpin:
+	unpin_user_pages(&page, 1);
+dec_account:
+	account_locked_vm(mm, 1, false);
+	return ret;
+}
+
 /**
  * kvm_handle_guest_abort - handles all 2nd stage aborts
  * @vcpu:	the VCPU pointer
-- 
2.55.0.1082.g2b9226bbc0-goog