Re: [PATCH v12 18/45] KVM: guest_memfd: Handle lru_add fbatch refcounts during conversion safety check

+
 static bool kvm_gmem_has_outstanding_references(struct inode *inode,
 						pgoff_t start, size_t nr_pages,
 						pgoff_t *err_index)
 {
+	enum lru_cache_drained drained = LRU_CACHE_NOT_DRAINED;
 	struct address_space *mapping = inode->i_mapping;
 	pgoff_t last = start + nr_pages - 1;
 	bool has_outstanding = false;

@@ -570,17 +589,12 @@ static bool kvm_gmem_has_outstanding_references(struct inode *inode,
 	folio_batch_init(&fbatch);
 
 	next = start;
-	while (has_outstanding && filemap_get_folios(mapping, &next, last, &fbatch)) {
+	while (!has_outstanding && filemap_get_folios(mapping, &next, last, &fbatch)) {
 		for (i = 0; i < folio_batch_count(&fbatch); ++i) {
 			struct folio *folio = fbatch.folios[i];
 
-			/*
-			 * Outstanding references are anything other than those
-			 * from the page cache, plus 1 temporary reference held
-			 * by filemap_get_folios() in the folio batch.
-			 */
-			if (folio_ref_count(folio) != folio_nr_pages(folio) + 1) {
-				has_outstanding = true;
+			has_outstanding = __folio_has_outstanding_references(folio, &drained);
+			if (has_outstanding) {
 				*err_index = max(start, folio->index);
 				break;
 			}