v4.19.13 snapshot.
diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c
new file mode 100644
index 0000000..2b656e6
--- /dev/null
+++ b/arch/powerpc/mm/init-common.c
@@ -0,0 +1,105 @@
+/*
+ * PowerPC version
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * Dave Engebretsen <engebret@us.ibm.com>
+ * Rework for PPC64 port.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#undef DEBUG
+
+#include <linux/string.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+static void pgd_ctor(void *addr)
+{
+ memset(addr, 0, PGD_TABLE_SIZE);
+}
+
+static void pud_ctor(void *addr)
+{
+ memset(addr, 0, PUD_TABLE_SIZE);
+}
+
+static void pmd_ctor(void *addr)
+{
+ memset(addr, 0, PMD_TABLE_SIZE);
+}
+
+struct kmem_cache *pgtable_cache[MAX_PGTABLE_INDEX_SIZE];
+EXPORT_SYMBOL_GPL(pgtable_cache); /* used by kvm_hv module */
+
+/*
+ * Create a kmem_cache() for pagetables. This is not used for PTE
+ * pages - they're linked to struct page, come from the normal free
+ * pages pool and have a different entry size (see real_pte_t) to
+ * everything else. Caches created by this function are used for all
+ * the higher level pagetables, and for hugepage pagetables.
+ */
+void pgtable_cache_add(unsigned shift, void (*ctor)(void *))
+{
+ char *name;
+ unsigned long table_size = sizeof(void *) << shift;
+ unsigned long align = table_size;
+
+ /* When batching pgtable pointers for RCU freeing, we store
+ * the index size in the low bits. Table alignment must be
+ * big enough to fit it.
+ *
+ * Likewise, hugeapge pagetable pointers contain a (different)
+ * shift value in the low bits. All tables must be aligned so
+ * as to leave enough 0 bits in the address to contain it. */
+ unsigned long minalign = max(MAX_PGTABLE_INDEX_SIZE + 1,
+ HUGEPD_SHIFT_MASK + 1);
+ struct kmem_cache *new;
+
+ /* It would be nice if this was a BUILD_BUG_ON(), but at the
+ * moment, gcc doesn't seem to recognize is_power_of_2 as a
+ * constant expression, so so much for that. */
+ BUG_ON(!is_power_of_2(minalign));
+ BUG_ON((shift < 1) || (shift > MAX_PGTABLE_INDEX_SIZE));
+
+ if (PGT_CACHE(shift))
+ return; /* Already have a cache of this size */
+
+ align = max_t(unsigned long, align, minalign);
+ name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift);
+ new = kmem_cache_create(name, table_size, align, 0, ctor);
+ if (!new)
+ panic("Could not allocate pgtable cache for order %d", shift);
+
+ kfree(name);
+ pgtable_cache[shift - 1] = new;
+
+ pr_debug("Allocated pgtable cache for order %d\n", shift);
+}
+EXPORT_SYMBOL_GPL(pgtable_cache_add); /* used by kvm_hv module */
+
+void pgtable_cache_init(void)
+{
+ pgtable_cache_add(PGD_INDEX_SIZE, pgd_ctor);
+
+ if (PMD_CACHE_INDEX && !PGT_CACHE(PMD_CACHE_INDEX))
+ pgtable_cache_add(PMD_CACHE_INDEX, pmd_ctor);
+ /*
+ * In all current configs, when the PUD index exists it's the
+ * same size as either the pgd or pmd index except with THP enabled
+ * on book3s 64
+ */
+ if (PUD_CACHE_INDEX && !PGT_CACHE(PUD_CACHE_INDEX))
+ pgtable_cache_add(PUD_CACHE_INDEX, pud_ctor);
+}