v4.19.13 snapshot.
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
new file mode 100644
index 0000000..f78793a
--- /dev/null
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPARC64 Huge TLB page support.
+ *
+ * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/sched/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/sysctl.h>
+
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+
+/* Slightly simplified from the non-hugepage variant because by
+ * definition we don't have to worry about any page coloring stuff
+ */
+
+static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
+							unsigned long addr,
+							unsigned long len,
+							unsigned long pgoff,
+							unsigned long flags)
+{
+	struct hstate *h = hstate_file(filp);
+	unsigned long task_size = TASK_SIZE;
+	struct vm_unmapped_area_info info;
+
+	if (test_thread_flag(TIF_32BIT))
+		task_size = STACK_TOP32;
+
+	info.flags = 0;
+	info.length = len;
+	info.low_limit = TASK_UNMAPPED_BASE;
+	info.high_limit = min(task_size, VA_EXCLUDE_START);
+	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
+	info.align_offset = 0;
+	addr = vm_unmapped_area(&info);
+
+	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
+		VM_BUG_ON(addr != -ENOMEM);
+		info.low_limit = VA_EXCLUDE_END;
+		info.high_limit = task_size;
+		addr = vm_unmapped_area(&info);
+	}
+
+	return addr;
+}
+
+static unsigned long
+hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+				  const unsigned long len,
+				  const unsigned long pgoff,
+				  const unsigned long flags)
+{
+	struct hstate *h = hstate_file(filp);
+	struct mm_struct *mm = current->mm;
+	unsigned long addr = addr0;
+	struct vm_unmapped_area_info info;
+
+	/* This should only ever run for 32-bit processes.  */
+	BUG_ON(!test_thread_flag(TIF_32BIT));
+
+	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
+	info.length = len;
+	info.low_limit = PAGE_SIZE;
+	info.high_limit = mm->mmap_base;
+	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
+	info.align_offset = 0;
+	addr = vm_unmapped_area(&info);
+
+	/*
+	 * A failed mmap() very likely causes application failure,
+	 * so fall back to the bottom-up function here. This scenario
+	 * can happen with large stack limits and large mmap()
+	 * allocations.
+	 */
+	if (addr & ~PAGE_MASK) {
+		VM_BUG_ON(addr != -ENOMEM);
+		info.flags = 0;
+		info.low_limit = TASK_UNMAPPED_BASE;
+		info.high_limit = STACK_TOP32;
+		addr = vm_unmapped_area(&info);
+	}
+
+	return addr;
+}
+
+unsigned long
+hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
+		unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+	struct hstate *h = hstate_file(file);
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long task_size = TASK_SIZE;
+
+	if (test_thread_flag(TIF_32BIT))
+		task_size = STACK_TOP32;
+
+	if (len & ~huge_page_mask(h))
+		return -EINVAL;
+	if (len > task_size)
+		return -ENOMEM;
+
+	if (flags & MAP_FIXED) {
+		if (prepare_hugepage_range(file, addr, len))
+			return -EINVAL;
+		return addr;
+	}
+
+	if (addr) {
+		addr = ALIGN(addr, huge_page_size(h));
+		vma = find_vma(mm, addr);
+		if (task_size - len >= addr &&
+		    (!vma || addr + len <= vm_start_gap(vma)))
+			return addr;
+	}
+	if (mm->get_unmapped_area == arch_get_unmapped_area)
+		return hugetlb_get_unmapped_area_bottomup(file, addr, len,
+				pgoff, flags);
+	else
+		return hugetlb_get_unmapped_area_topdown(file, addr, len,
+				pgoff, flags);
+}
+
+static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
+{
+	return entry;
+}
+
+static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
+{
+	unsigned long hugepage_size = _PAGE_SZ4MB_4V;
+
+	pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V;
+
+	switch (shift) {
+	case HPAGE_16GB_SHIFT:
+		hugepage_size = _PAGE_SZ16GB_4V;
+		pte_val(entry) |= _PAGE_PUD_HUGE;
+		break;
+	case HPAGE_2GB_SHIFT:
+		hugepage_size = _PAGE_SZ2GB_4V;
+		pte_val(entry) |= _PAGE_PMD_HUGE;
+		break;
+	case HPAGE_256MB_SHIFT:
+		hugepage_size = _PAGE_SZ256MB_4V;
+		pte_val(entry) |= _PAGE_PMD_HUGE;
+		break;
+	case HPAGE_SHIFT:
+		pte_val(entry) |= _PAGE_PMD_HUGE;
+		break;
+	case HPAGE_64K_SHIFT:
+		hugepage_size = _PAGE_SZ64K_4V;
+		break;
+	default:
+		WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift);
+	}
+
+	pte_val(entry) = pte_val(entry) | hugepage_size;
+	return entry;
+}
+
+static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift)
+{
+	if (tlb_type == hypervisor)
+		return sun4v_hugepage_shift_to_tte(entry, shift);
+	else
+		return sun4u_hugepage_shift_to_tte(entry, shift);
+}
+
+pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
+			 struct page *page, int writeable)
+{
+	unsigned int shift = huge_page_shift(hstate_vma(vma));
+	pte_t pte;
+
+	pte = hugepage_shift_to_tte(entry, shift);
+
+#ifdef CONFIG_SPARC64
+	/* If this vma has ADI enabled on it, turn on TTE.mcd
+	 */
+	if (vma->vm_flags & VM_SPARC_ADI)
+		return pte_mkmcd(pte);
+	else
+		return pte_mknotmcd(pte);
+#else
+	return pte;
+#endif
+}
+
+static unsigned int sun4v_huge_tte_to_shift(pte_t entry)
+{
+	unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V;
+	unsigned int shift;
+
+	switch (tte_szbits) {
+	case _PAGE_SZ16GB_4V:
+		shift = HPAGE_16GB_SHIFT;
+		break;
+	case _PAGE_SZ2GB_4V:
+		shift = HPAGE_2GB_SHIFT;
+		break;
+	case _PAGE_SZ256MB_4V:
+		shift = HPAGE_256MB_SHIFT;
+		break;
+	case _PAGE_SZ4MB_4V:
+		shift = REAL_HPAGE_SHIFT;
+		break;
+	case _PAGE_SZ64K_4V:
+		shift = HPAGE_64K_SHIFT;
+		break;
+	default:
+		shift = PAGE_SHIFT;
+		break;
+	}
+	return shift;
+}
+
+static unsigned int sun4u_huge_tte_to_shift(pte_t entry)
+{
+	unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U;
+	unsigned int shift;
+
+	switch (tte_szbits) {
+	case _PAGE_SZ256MB_4U:
+		shift = HPAGE_256MB_SHIFT;
+		break;
+	case _PAGE_SZ4MB_4U:
+		shift = REAL_HPAGE_SHIFT;
+		break;
+	case _PAGE_SZ64K_4U:
+		shift = HPAGE_64K_SHIFT;
+		break;
+	default:
+		shift = PAGE_SHIFT;
+		break;
+	}
+	return shift;
+}
+
+static unsigned int huge_tte_to_shift(pte_t entry)
+{
+	unsigned long shift;
+
+	if (tlb_type == hypervisor)
+		shift = sun4v_huge_tte_to_shift(entry);
+	else
+		shift = sun4u_huge_tte_to_shift(entry);
+
+	if (shift == PAGE_SHIFT)
+		WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n",
+			  pte_val(entry));
+
+	return shift;
+}
+
+static unsigned long huge_tte_to_size(pte_t pte)
+{
+	unsigned long size = 1UL << huge_tte_to_shift(pte);
+
+	if (size == REAL_HPAGE_SIZE)
+		size = HPAGE_SIZE;
+	return size;
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+			unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd = pgd_offset(mm, addr);
+	pud = pud_alloc(mm, pgd, addr);
+	if (!pud)
+		return NULL;
+	if (sz >= PUD_SIZE)
+		return (pte_t *)pud;
+	pmd = pmd_alloc(mm, pud, addr);
+	if (!pmd)
+		return NULL;
+	if (sz >= PMD_SIZE)
+		return (pte_t *)pmd;
+	return pte_alloc_map(mm, pmd, addr);
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm,
+		       unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd = pgd_offset(mm, addr);
+	if (pgd_none(*pgd))
+		return NULL;
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return NULL;
+	if (is_hugetlb_pud(*pud))
+		return (pte_t *)pud;
+	pmd = pmd_offset(pud, addr);
+	if (pmd_none(*pmd))
+		return NULL;
+	if (is_hugetlb_pmd(*pmd))
+		return (pte_t *)pmd;
+	return pte_offset_map(pmd, addr);
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+		     pte_t *ptep, pte_t entry)
+{
+	unsigned int nptes, orig_shift, shift;
+	unsigned long i, size;
+	pte_t orig;
+
+	size = huge_tte_to_size(entry);
+
+	shift = PAGE_SHIFT;
+	if (size >= PUD_SIZE)
+		shift = PUD_SHIFT;
+	else if (size >= PMD_SIZE)
+		shift = PMD_SHIFT;
+	else
+		shift = PAGE_SHIFT;
+
+	nptes = size >> shift;
+
+	if (!pte_present(*ptep) && pte_present(entry))
+		mm->context.hugetlb_pte_count += nptes;
+
+	addr &= ~(size - 1);
+	orig = *ptep;
+	orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig);
+
+	for (i = 0; i < nptes; i++)
+		ptep[i] = __pte(pte_val(entry) + (i << shift));
+
+	maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift);
+	/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
+	if (size == HPAGE_SIZE)
+		maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0,
+				    orig_shift);
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep)
+{
+	unsigned int i, nptes, orig_shift, shift;
+	unsigned long size;
+	pte_t entry;
+
+	entry = *ptep;
+	size = huge_tte_to_size(entry);
+
+	shift = PAGE_SHIFT;
+	if (size >= PUD_SIZE)
+		shift = PUD_SHIFT;
+	else if (size >= PMD_SIZE)
+		shift = PMD_SHIFT;
+	else
+		shift = PAGE_SHIFT;
+
+	nptes = size >> shift;
+	orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry);
+
+	if (pte_present(entry))
+		mm->context.hugetlb_pte_count -= nptes;
+
+	addr &= ~(size - 1);
+	for (i = 0; i < nptes; i++)
+		ptep[i] = __pte(0UL);
+
+	maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift);
+	/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
+	if (size == HPAGE_SIZE)
+		maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0,
+				    orig_shift);
+
+	return entry;
+}
+
+int pmd_huge(pmd_t pmd)
+{
+	return !pmd_none(pmd) &&
+		(pmd_val(pmd) & (_PAGE_VALID|_PAGE_PMD_HUGE)) != _PAGE_VALID;
+}
+
+int pud_huge(pud_t pud)
+{
+	return !pud_none(pud) &&
+		(pud_val(pud) & (_PAGE_VALID|_PAGE_PUD_HUGE)) != _PAGE_VALID;
+}
+
+static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
+			   unsigned long addr)
+{
+	pgtable_t token = pmd_pgtable(*pmd);
+
+	pmd_clear(pmd);
+	pte_free_tlb(tlb, token, addr);
+	mm_dec_nr_ptes(tlb->mm);
+}
+
+static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
+				   unsigned long addr, unsigned long end,
+				   unsigned long floor, unsigned long ceiling)
+{
+	pmd_t *pmd;
+	unsigned long next;
+	unsigned long start;
+
+	start = addr;
+	pmd = pmd_offset(pud, addr);
+	do {
+		next = pmd_addr_end(addr, end);
+		if (pmd_none(*pmd))
+			continue;
+		if (is_hugetlb_pmd(*pmd))
+			pmd_clear(pmd);
+		else
+			hugetlb_free_pte_range(tlb, pmd, addr);
+	} while (pmd++, addr = next, addr != end);
+
+	start &= PUD_MASK;
+	if (start < floor)
+		return;
+	if (ceiling) {
+		ceiling &= PUD_MASK;
+		if (!ceiling)
+			return;
+	}
+	if (end - 1 > ceiling - 1)
+		return;
+
+	pmd = pmd_offset(pud, start);
+	pud_clear(pud);
+	pmd_free_tlb(tlb, pmd, start);
+	mm_dec_nr_pmds(tlb->mm);
+}
+
+static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
+				   unsigned long addr, unsigned long end,
+				   unsigned long floor, unsigned long ceiling)
+{
+	pud_t *pud;
+	unsigned long next;
+	unsigned long start;
+
+	start = addr;
+	pud = pud_offset(pgd, addr);
+	do {
+		next = pud_addr_end(addr, end);
+		if (pud_none_or_clear_bad(pud))
+			continue;
+		if (is_hugetlb_pud(*pud))
+			pud_clear(pud);
+		else
+			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
+					       ceiling);
+	} while (pud++, addr = next, addr != end);
+
+	start &= PGDIR_MASK;
+	if (start < floor)
+		return;
+	if (ceiling) {
+		ceiling &= PGDIR_MASK;
+		if (!ceiling)
+			return;
+	}
+	if (end - 1 > ceiling - 1)
+		return;
+
+	pud = pud_offset(pgd, start);
+	pgd_clear(pgd);
+	pud_free_tlb(tlb, pud, start);
+	mm_dec_nr_puds(tlb->mm);
+}
+
+void hugetlb_free_pgd_range(struct mmu_gather *tlb,
+			    unsigned long addr, unsigned long end,
+			    unsigned long floor, unsigned long ceiling)
+{
+	pgd_t *pgd;
+	unsigned long next;
+
+	addr &= PMD_MASK;
+	if (addr < floor) {
+		addr += PMD_SIZE;
+		if (!addr)
+			return;
+	}
+	if (ceiling) {
+		ceiling &= PMD_MASK;
+		if (!ceiling)
+			return;
+	}
+	if (end - 1 > ceiling - 1)
+		end -= PMD_SIZE;
+	if (addr > end - 1)
+		return;
+
+	pgd = pgd_offset(tlb->mm, addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		if (pgd_none_or_clear_bad(pgd))
+			continue;
+		hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
+	} while (pgd++, addr = next, addr != end);
+}