v4.19.13 snapshot.
diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
new file mode 100644
index 0000000..d16e419
--- /dev/null
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IA-64 Huge TLB Page Support for Kernel.
+ *
+ * Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com>
+ * Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com>
+ *
+ * Sep, 2003: add numa support
+ * Feb, 2004: dynamic hugetlb page size via boot parameter
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/module.h>
+#include <linux/sysctl.h>
+#include <linux/log2.h>
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+
+unsigned int hpage_shift = HPAGE_SHIFT_DEFAULT;
+EXPORT_SYMBOL(hpage_shift);
+
+pte_t *
+huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)
+{
+ unsigned long taddr = htlbpage_to_page(addr);
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte = NULL;
+
+ pgd = pgd_offset(mm, taddr);
+ pud = pud_alloc(mm, pgd, taddr);
+ if (pud) {
+ pmd = pmd_alloc(mm, pud, taddr);
+ if (pmd)
+ pte = pte_alloc_map(mm, pmd, taddr);
+ }
+ return pte;
+}
+
+pte_t *
+huge_pte_offset (struct mm_struct *mm, unsigned long addr, unsigned long sz)
+{
+ unsigned long taddr = htlbpage_to_page(addr);
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte = NULL;
+
+ pgd = pgd_offset(mm, taddr);
+ if (pgd_present(*pgd)) {
+ pud = pud_offset(pgd, taddr);
+ if (pud_present(*pud)) {
+ pmd = pmd_offset(pud, taddr);
+ if (pmd_present(*pmd))
+ pte = pte_offset_map(pmd, taddr);
+ }
+ }
+
+ return pte;
+}
+
+#define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; }
+
+/*
+ * Don't actually need to do any preparation, but need to make sure
+ * the address is in the right region.
+ */
+int prepare_hugepage_range(struct file *file,
+ unsigned long addr, unsigned long len)
+{
+ if (len & ~HPAGE_MASK)
+ return -EINVAL;
+ if (addr & ~HPAGE_MASK)
+ return -EINVAL;
+ if (REGION_NUMBER(addr) != RGN_HPAGE)
+ return -EINVAL;
+
+ return 0;
+}
+
+struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write)
+{
+ struct page *page;
+ pte_t *ptep;
+
+ if (REGION_NUMBER(addr) != RGN_HPAGE)
+ return ERR_PTR(-EINVAL);
+
+ ptep = huge_pte_offset(mm, addr, HPAGE_SIZE);
+ if (!ptep || pte_none(*ptep))
+ return NULL;
+ page = pte_page(*ptep);
+ page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT);
+ return page;
+}
+int pmd_huge(pmd_t pmd)
+{
+ return 0;
+}
+
+int pud_huge(pud_t pud)
+{
+ return 0;
+}
+
+void hugetlb_free_pgd_range(struct mmu_gather *tlb,
+ unsigned long addr, unsigned long end,
+ unsigned long floor, unsigned long ceiling)
+{
+ /*
+ * This is called to free hugetlb page tables.
+ *
+ * The offset of these addresses from the base of the hugetlb
+ * region must be scaled down by HPAGE_SIZE/PAGE_SIZE so that
+ * the standard free_pgd_range will free the right page tables.
+ *
+ * If floor and ceiling are also in the hugetlb region, they
+ * must likewise be scaled down; but if outside, left unchanged.
+ */
+
+ addr = htlbpage_to_page(addr);
+ end = htlbpage_to_page(end);
+ if (REGION_NUMBER(floor) == RGN_HPAGE)
+ floor = htlbpage_to_page(floor);
+ if (REGION_NUMBER(ceiling) == RGN_HPAGE)
+ ceiling = htlbpage_to_page(ceiling);
+
+ free_pgd_range(tlb, addr, end, floor, ceiling);
+}
+
+unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
+ unsigned long pgoff, unsigned long flags)
+{
+ struct vm_unmapped_area_info info;
+
+ if (len > RGN_MAP_LIMIT)
+ return -ENOMEM;
+ if (len & ~HPAGE_MASK)
+ return -EINVAL;
+
+ /* Handle MAP_FIXED */
+ if (flags & MAP_FIXED) {
+ if (prepare_hugepage_range(file, addr, len))
+ return -EINVAL;
+ return addr;
+ }
+
+ /* This code assumes that RGN_HPAGE != 0. */
+ if ((REGION_NUMBER(addr) != RGN_HPAGE) || (addr & (HPAGE_SIZE - 1)))
+ addr = HPAGE_REGION_BASE;
+
+ info.flags = 0;
+ info.length = len;
+ info.low_limit = addr;
+ info.high_limit = HPAGE_REGION_BASE + RGN_MAP_LIMIT;
+ info.align_mask = PAGE_MASK & (HPAGE_SIZE - 1);
+ info.align_offset = 0;
+ return vm_unmapped_area(&info);
+}
+
+static int __init hugetlb_setup_sz(char *str)
+{
+ u64 tr_pages;
+ unsigned long long size;
+
+ if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0)
+ /*
+ * shouldn't happen, but just in case.
+ */
+ tr_pages = 0x15557000UL;
+
+ size = memparse(str, &str);
+ if (*str || !is_power_of_2(size) || !(tr_pages & size) ||
+ size <= PAGE_SIZE ||
+ size >= (1UL << PAGE_SHIFT << MAX_ORDER)) {
+ printk(KERN_WARNING "Invalid huge page size specified\n");
+ return 1;
+ }
+
+ hpage_shift = __ffs(size);
+ /*
+ * boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT
+ * override here with new page shift.
+ */
+ ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2);
+ return 0;
+}
+early_param("hugepagesz", hugetlb_setup_sz);