v4.19.13 snapshot.
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
new file mode 100644
index 0000000..b0246c7
--- /dev/null
+++ b/arch/s390/mm/hugetlbpage.c
@@ -0,0 +1,269 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IBM System z Huge TLB Page Support for Kernel.
+ *
+ * Copyright IBM Corp. 2007,2016
+ * Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
+ */
+
+#define KMSG_COMPONENT "hugetlb"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+
+/*
+ * If the bit selected by single-bit bitmask "a" is set within "x", move
+ * it to the position indicated by single-bit bitmask "b".
+ */
+#define move_set_bit(x, a, b) (((x) & (a)) >> ilog2(a) << ilog2(b))
+
+static inline unsigned long __pte_to_rste(pte_t pte)
+{
+ unsigned long rste;
+
+ /*
+ * Convert encoding pte bits pmd / pud bits
+ * lIR.uswrdy.p dy..R...I...wr
+ * empty 010.000000.0 -> 00..0...1...00
+ * prot-none, clean, old 111.000000.1 -> 00..1...1...00
+ * prot-none, clean, young 111.000001.1 -> 01..1...1...00
+ * prot-none, dirty, old 111.000010.1 -> 10..1...1...00
+ * prot-none, dirty, young 111.000011.1 -> 11..1...1...00
+ * read-only, clean, old 111.000100.1 -> 00..1...1...01
+ * read-only, clean, young 101.000101.1 -> 01..1...0...01
+ * read-only, dirty, old 111.000110.1 -> 10..1...1...01
+ * read-only, dirty, young 101.000111.1 -> 11..1...0...01
+ * read-write, clean, old 111.001100.1 -> 00..1...1...11
+ * read-write, clean, young 101.001101.1 -> 01..1...0...11
+ * read-write, dirty, old 110.001110.1 -> 10..0...1...11
+ * read-write, dirty, young 100.001111.1 -> 11..0...0...11
+ * HW-bits: R read-only, I invalid
+ * SW-bits: p present, y young, d dirty, r read, w write, s special,
+ * u unused, l large
+ */
+ if (pte_present(pte)) {
+ rste = pte_val(pte) & PAGE_MASK;
+ rste |= move_set_bit(pte_val(pte), _PAGE_READ,
+ _SEGMENT_ENTRY_READ);
+ rste |= move_set_bit(pte_val(pte), _PAGE_WRITE,
+ _SEGMENT_ENTRY_WRITE);
+ rste |= move_set_bit(pte_val(pte), _PAGE_INVALID,
+ _SEGMENT_ENTRY_INVALID);
+ rste |= move_set_bit(pte_val(pte), _PAGE_PROTECT,
+ _SEGMENT_ENTRY_PROTECT);
+ rste |= move_set_bit(pte_val(pte), _PAGE_DIRTY,
+ _SEGMENT_ENTRY_DIRTY);
+ rste |= move_set_bit(pte_val(pte), _PAGE_YOUNG,
+ _SEGMENT_ENTRY_YOUNG);
+#ifdef CONFIG_MEM_SOFT_DIRTY
+ rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
+ _SEGMENT_ENTRY_SOFT_DIRTY);
+#endif
+ rste |= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
+ _SEGMENT_ENTRY_NOEXEC);
+ } else
+ rste = _SEGMENT_ENTRY_EMPTY;
+ return rste;
+}
+
+static inline pte_t __rste_to_pte(unsigned long rste)
+{
+ int present;
+ pte_t pte;
+
+ if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ present = pud_present(__pud(rste));
+ else
+ present = pmd_present(__pmd(rste));
+
+ /*
+ * Convert encoding pmd / pud bits pte bits
+ * dy..R...I...wr lIR.uswrdy.p
+ * empty 00..0...1...00 -> 010.000000.0
+ * prot-none, clean, old 00..1...1...00 -> 111.000000.1
+ * prot-none, clean, young 01..1...1...00 -> 111.000001.1
+ * prot-none, dirty, old 10..1...1...00 -> 111.000010.1
+ * prot-none, dirty, young 11..1...1...00 -> 111.000011.1
+ * read-only, clean, old 00..1...1...01 -> 111.000100.1
+ * read-only, clean, young 01..1...0...01 -> 101.000101.1
+ * read-only, dirty, old 10..1...1...01 -> 111.000110.1
+ * read-only, dirty, young 11..1...0...01 -> 101.000111.1
+ * read-write, clean, old 00..1...1...11 -> 111.001100.1
+ * read-write, clean, young 01..1...0...11 -> 101.001101.1
+ * read-write, dirty, old 10..0...1...11 -> 110.001110.1
+ * read-write, dirty, young 11..0...0...11 -> 100.001111.1
+ * HW-bits: R read-only, I invalid
+ * SW-bits: p present, y young, d dirty, r read, w write, s special,
+ * u unused, l large
+ */
+ if (present) {
+ pte_val(pte) = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
+ pte_val(pte) |= _PAGE_LARGE | _PAGE_PRESENT;
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_READ,
+ _PAGE_READ);
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE,
+ _PAGE_WRITE);
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID,
+ _PAGE_INVALID);
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT,
+ _PAGE_PROTECT);
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY,
+ _PAGE_DIRTY);
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG,
+ _PAGE_YOUNG);
+#ifdef CONFIG_MEM_SOFT_DIRTY
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY,
+ _PAGE_DIRTY);
+#endif
+ pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC,
+ _PAGE_NOEXEC);
+ } else
+ pte_val(pte) = _PAGE_INVALID;
+ return pte;
+}
+
+static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
+{
+ struct page *page;
+ unsigned long size, paddr;
+
+ if (!mm_uses_skeys(mm) ||
+ rste & _SEGMENT_ENTRY_INVALID)
+ return;
+
+ if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
+ page = pud_page(__pud(rste));
+ size = PUD_SIZE;
+ paddr = rste & PUD_MASK;
+ } else {
+ page = pmd_page(__pmd(rste));
+ size = PMD_SIZE;
+ paddr = rste & PMD_MASK;
+ }
+
+ if (!test_and_set_bit(PG_arch_1, &page->flags))
+ __storage_key_init_range(paddr, paddr + size - 1);
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ unsigned long rste;
+
+ rste = __pte_to_rste(pte);
+ if (!MACHINE_HAS_NX)
+ rste &= ~_SEGMENT_ENTRY_NOEXEC;
+
+ /* Set correct table type for 2G hugepages */
+ if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ rste |= _REGION_ENTRY_TYPE_R3 | _REGION3_ENTRY_LARGE;
+ else
+ rste |= _SEGMENT_ENTRY_LARGE;
+ clear_huge_pte_skeys(mm, rste);
+ pte_val(*ptep) = rste;
+}
+
+pte_t huge_ptep_get(pte_t *ptep)
+{
+ return __rste_to_pte(pte_val(*ptep));
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ pte_t pte = huge_ptep_get(ptep);
+ pmd_t *pmdp = (pmd_t *) ptep;
+ pud_t *pudp = (pud_t *) ptep;
+
+ if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
+ else
+ pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
+ return pte;
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+ unsigned long addr, unsigned long sz)
+{
+ pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
+ pmd_t *pmdp = NULL;
+
+ pgdp = pgd_offset(mm, addr);
+ p4dp = p4d_alloc(mm, pgdp, addr);
+ if (p4dp) {
+ pudp = pud_alloc(mm, p4dp, addr);
+ if (pudp) {
+ if (sz == PUD_SIZE)
+ return (pte_t *) pudp;
+ else if (sz == PMD_SIZE)
+ pmdp = pmd_alloc(mm, pudp, addr);
+ }
+ }
+ return (pte_t *) pmdp;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm,
+ unsigned long addr, unsigned long sz)
+{
+ pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
+ pmd_t *pmdp = NULL;
+
+ pgdp = pgd_offset(mm, addr);
+ if (pgd_present(*pgdp)) {
+ p4dp = p4d_offset(pgdp, addr);
+ if (p4d_present(*p4dp)) {
+ pudp = pud_offset(p4dp, addr);
+ if (pud_present(*pudp)) {
+ if (pud_large(*pudp))
+ return (pte_t *) pudp;
+ pmdp = pmd_offset(pudp, addr);
+ }
+ }
+ }
+ return (pte_t *) pmdp;
+}
+
+int pmd_huge(pmd_t pmd)
+{
+ return pmd_large(pmd);
+}
+
+int pud_huge(pud_t pud)
+{
+ return pud_large(pud);
+}
+
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+ pud_t *pud, int flags)
+{
+ if (flags & FOLL_GET)
+ return NULL;
+
+ return pud_page(*pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT);
+}
+
+static __init int setup_hugepagesz(char *opt)
+{
+ unsigned long size;
+ char *string = opt;
+
+ size = memparse(opt, &opt);
+ if (MACHINE_HAS_EDAT1 && size == PMD_SIZE) {
+ hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
+ } else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE) {
+ hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+ } else {
+ hugetlb_bad_size();
+ pr_err("hugepagesz= specifies an unsupported page size %s\n",
+ string);
+ return 0;
+ }
+ return 1;
+}
+__setup("hugepagesz=", setup_hugepagesz);