v4.19.13 snapshot.
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
new file mode 100644
index 0000000..b320f50
--- /dev/null
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PPC64 Huge TLB Page Support for hash based MMUs (POWER4 and later)
+ *
+ * Copyright (C) 2003 David Gibson, IBM Corporation.
+ *
+ * Based on the IA-32 version:
+ * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/machdep.h>
+
+extern long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
+ unsigned long pa, unsigned long rlags,
+ unsigned long vflags, int psize, int ssize);
+
+int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
+ pte_t *ptep, unsigned long trap, unsigned long flags,
+ int ssize, unsigned int shift, unsigned int mmu_psize)
+{
+ real_pte_t rpte;
+ unsigned long vpn;
+ unsigned long old_pte, new_pte;
+ unsigned long rflags, pa, sz;
+ long slot, offset;
+
+ BUG_ON(shift != mmu_psize_defs[mmu_psize].shift);
+
+ /* Search the Linux page table for a match with va */
+ vpn = hpt_vpn(ea, vsid, ssize);
+
+ /* At this point, we have a pte (old_pte) which can be used to build
+ * or update an HPTE. There are 2 cases:
+ *
+ * 1. There is a valid (present) pte with no associated HPTE (this is
+ * the most common case)
+ * 2. There is a valid (present) pte with an associated HPTE. The
+ * current values of the pp bits in the HPTE prevent access
+ * because we are doing software DIRTY bit management and the
+ * page is currently not DIRTY.
+ */
+
+
+ do {
+ old_pte = pte_val(*ptep);
+ /* If PTE busy, retry the access */
+ if (unlikely(old_pte & H_PAGE_BUSY))
+ return 0;
+ /* If PTE permissions don't match, take page fault */
+ if (unlikely(!check_pte_access(access, old_pte)))
+ return 1;
+
+ /* Try to lock the PTE, add ACCESSED and DIRTY if it was
+ * a write access */
+ new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED;
+ if (access & _PAGE_WRITE)
+ new_pte |= _PAGE_DIRTY;
+ } while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
+
+ rflags = htab_convert_pte_flags(new_pte);
+ if (unlikely(mmu_psize == MMU_PAGE_16G))
+ offset = PTRS_PER_PUD;
+ else
+ offset = PTRS_PER_PMD;
+ rpte = __real_pte(__pte(old_pte), ptep, offset);
+
+ sz = ((1UL) << shift);
+ if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
+ /* No CPU has hugepages but lacks no execute, so we
+ * don't need to worry about that case */
+ rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);
+
+ /* Check if pte already has an hpte (case 2) */
+ if (unlikely(old_pte & H_PAGE_HASHPTE)) {
+ /* There MIGHT be an HPTE for this pte */
+ unsigned long gslot;
+
+ gslot = pte_get_hash_gslot(vpn, shift, ssize, rpte, 0);
+ if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, mmu_psize,
+ mmu_psize, ssize, flags) == -1)
+ old_pte &= ~_PAGE_HPTEFLAGS;
+ }
+
+ if (likely(!(old_pte & H_PAGE_HASHPTE))) {
+ unsigned long hash = hpt_hash(vpn, shift, ssize);
+
+ pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
+
+ /* clear HPTE slot informations in new PTE */
+ new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE;
+
+ slot = hpte_insert_repeating(hash, vpn, pa, rflags, 0,
+ mmu_psize, ssize);
+
+ /*
+ * Hypervisor failure. Restore old pte and return -1
+ * similar to __hash_page_*
+ */
+ if (unlikely(slot == -2)) {
+ *ptep = __pte(old_pte);
+ hash_failure_debug(ea, access, vsid, trap, ssize,
+ mmu_psize, mmu_psize, old_pte);
+ return -1;
+ }
+
+ new_pte |= pte_set_hidx(ptep, rpte, 0, slot, offset);
+ }
+
+ /*
+ * No need to use ldarx/stdcx here
+ */
+ *ptep = __pte(new_pte & ~H_PAGE_BUSY);
+ return 0;
+}