v4.19.13 snapshot.
diff --git a/arch/um/include/asm/pgalloc.h b/arch/um/include/asm/pgalloc.h
new file mode 100644
index 0000000..bf90b2a
--- /dev/null
+++ b/arch/um/include/asm/pgalloc.h
@@ -0,0 +1,61 @@
+/* 
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright 2003 PathScale, Inc.
+ * Derived from include/asm-i386/pgalloc.h and include/asm-i386/pgtable.h
+ * Licensed under the GPL
+ */
+
+#ifndef __UM_PGALLOC_H
+#define __UM_PGALLOC_H
+
+#include <linux/mm.h>
+
+#define pmd_populate_kernel(mm, pmd, pte) \
+	set_pmd(pmd, __pmd(_PAGE_TABLE + (unsigned long) __pa(pte)))
+
+#define pmd_populate(mm, pmd, pte) 				\
+	set_pmd(pmd, __pmd(_PAGE_TABLE +			\
+		((unsigned long long)page_to_pfn(pte) <<	\
+			(unsigned long long) PAGE_SHIFT)))
+#define pmd_pgtable(pmd) pmd_page(pmd)
+
+/*
+ * Allocate and free page tables.
+ */
+extern pgd_t *pgd_alloc(struct mm_struct *);
+extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
+
+extern pte_t *pte_alloc_one_kernel(struct mm_struct *, unsigned long);
+extern pgtable_t pte_alloc_one(struct mm_struct *, unsigned long);
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+	free_page((unsigned long) pte);
+}
+
+static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
+{
+	pgtable_page_dtor(pte);
+	__free_page(pte);
+}
+
+#define __pte_free_tlb(tlb,pte, address)		\
+do {							\
+	pgtable_page_dtor(pte);				\
+	tlb_remove_page((tlb),(pte));			\
+} while (0)
+
+#ifdef CONFIG_3_LEVEL_PGTABLES
+
+static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
+{
+	free_page((unsigned long)pmd);
+}
+
+#define __pmd_free_tlb(tlb,x, address)   tlb_remove_page((tlb),virt_to_page(x))
+#endif
+
+#define check_pgt_cache()	do { } while (0)
+
+#endif
+