v4.19.13 snapshot.
diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h
new file mode 100644
index 0000000..5ee7337
--- /dev/null
+++ b/arch/s390/include/asm/pgalloc.h
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * S390 version
+ * Copyright IBM Corp. 1999, 2000
+ * Author(s): Hartmut Penner (hp@de.ibm.com)
+ * Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * Derived from "include/asm-i386/pgalloc.h"
+ * Copyright (C) 1994 Linus Torvalds
+ */
+
+#ifndef _S390_PGALLOC_H
+#define _S390_PGALLOC_H
+
+#include <linux/threads.h>
+#include <linux/string.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+
+#define CRST_ALLOC_ORDER 2
+
+unsigned long *crst_table_alloc(struct mm_struct *);
+void crst_table_free(struct mm_struct *, unsigned long *);
+
+unsigned long *page_table_alloc(struct mm_struct *);
+struct page *page_table_alloc_pgste(struct mm_struct *mm);
+void page_table_free(struct mm_struct *, unsigned long *);
+void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
+void page_table_free_pgste(struct page *page);
+extern int page_table_allocate_pgste;
+
+static inline void crst_table_init(unsigned long *crst, unsigned long entry)
+{
+ memset64((u64 *)crst, entry, _CRST_ENTRIES);
+}
+
+static inline unsigned long pgd_entry_type(struct mm_struct *mm)
+{
+ if (mm_pmd_folded(mm))
+ return _SEGMENT_ENTRY_EMPTY;
+ if (mm_pud_folded(mm))
+ return _REGION3_ENTRY_EMPTY;
+ if (mm_p4d_folded(mm))
+ return _REGION2_ENTRY_EMPTY;
+ return _REGION1_ENTRY_EMPTY;
+}
+
+int crst_table_upgrade(struct mm_struct *mm, unsigned long limit);
+void crst_table_downgrade(struct mm_struct *);
+
+static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address)
+{
+ unsigned long *table = crst_table_alloc(mm);
+
+ if (table)
+ crst_table_init(table, _REGION2_ENTRY_EMPTY);
+ return (p4d_t *) table;
+}
+#define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d)
+
+static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
+{
+ unsigned long *table = crst_table_alloc(mm);
+ if (table)
+ crst_table_init(table, _REGION3_ENTRY_EMPTY);
+ return (pud_t *) table;
+}
+#define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
+
+static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
+{
+ unsigned long *table = crst_table_alloc(mm);
+
+ if (!table)
+ return NULL;
+ crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
+ if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
+ crst_table_free(mm, table);
+ return NULL;
+ }
+ return (pmd_t *) table;
+}
+
+static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
+{
+ pgtable_pmd_page_dtor(virt_to_page(pmd));
+ crst_table_free(mm, (unsigned long *) pmd);
+}
+
+static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
+{
+ pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
+}
+
+static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
+{
+ p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
+}
+
+static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
+{
+ pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
+}
+
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+ unsigned long *table = crst_table_alloc(mm);
+
+ if (!table)
+ return NULL;
+ if (mm->context.asce_limit == _REGION3_SIZE) {
+ /* Forking a compat process with 2 page table levels */
+ if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
+ crst_table_free(mm, table);
+ return NULL;
+ }
+ }
+ return (pgd_t *) table;
+}
+
+static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+ if (mm->context.asce_limit == _REGION3_SIZE)
+ pgtable_pmd_page_dtor(virt_to_page(pgd));
+ crst_table_free(mm, (unsigned long *) pgd);
+}
+
+static inline void pmd_populate(struct mm_struct *mm,
+ pmd_t *pmd, pgtable_t pte)
+{
+ pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
+}
+
+#define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
+
+#define pmd_pgtable(pmd) \
+ (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
+
+/*
+ * page table entry allocation/free routines.
+ */
+#define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
+#define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
+
+#define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
+#define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
+
+extern void rcu_table_freelist_finish(void);
+
+void vmem_map_init(void);
+void *vmem_crst_alloc(unsigned long val);
+pte_t *vmem_pte_alloc(void);
+
+unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages);
+void base_asce_free(unsigned long asce);
+
+#endif /* _S390_PGALLOC_H */