JustOS/linux-6.13/arch/s390/mm/hugetlbpage.c
justuser 02e73b8cd9 up
2025-01-24 17:00:19 +03:00

258 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* IBM System z Huge TLB Page Support for Kernel.
*
* Copyright IBM Corp. 2007,2020
* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
*/
#define KMSG_COMPONENT "hugetlb"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <asm/pgalloc.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/mman.h>
#include <linux/sched/mm.h>
#include <linux/security.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)
{
swp_entry_t arch_entry;
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 |= _SEGMENT_ENTRY_PRESENT;
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 if (!pte_none(pte)) {
/* swap pte */
arch_entry = __pte_to_swp_entry(pte);
rste = mk_swap_rste(__swp_type(arch_entry), __swp_offset(arch_entry));
} else
rste = _SEGMENT_ENTRY_EMPTY;
return rste;
}
static inline pte_t __rste_to_pte(unsigned long rste)
{
swp_entry_t arch_entry;
unsigned long pteval;
int present, none;
pte_t pte;
if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
present = pud_present(__pud(rste));
none = pud_none(__pud(rste));
} else {
present = pmd_present(__pmd(rste));
none = pmd_none(__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) {
pteval = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
pteval |= _PAGE_LARGE | _PAGE_PRESENT;
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_READ, _PAGE_READ);
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE, _PAGE_WRITE);
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID, _PAGE_INVALID);
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT, _PAGE_PROTECT);
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY, _PAGE_DIRTY);
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG, _PAGE_YOUNG);
#ifdef CONFIG_MEM_SOFT_DIRTY
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY, _PAGE_SOFT_DIRTY);
#endif
pteval |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC, _PAGE_NOEXEC);
} else if (!none) {
/* swap rste */
arch_entry = __rste_to_swp_entry(rste);
pte = mk_swap_pte(__swp_type_rste(arch_entry), __swp_offset_rste(arch_entry));
pteval = pte_val(pte);
} else
pteval = _PAGE_INVALID;
return __pte(pteval);
}
static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
{
struct folio *folio;
unsigned long size, paddr;
if (!mm_uses_skeys(mm) ||
rste & _SEGMENT_ENTRY_INVALID)
return;
if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
folio = page_folio(pud_page(__pud(rste)));
size = PUD_SIZE;
paddr = rste & PUD_MASK;
} else {
folio = page_folio(pmd_page(__pmd(rste)));
size = PMD_SIZE;
paddr = rste & PMD_MASK;
}
if (!test_and_set_bit(PG_arch_1, &folio->flags))
__storage_key_init_range(paddr, paddr + size);
}
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);
/* Set correct table type for 2G hugepages */
if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
if (likely(pte_present(pte)))
rste |= _REGION3_ENTRY_LARGE;
rste |= _REGION_ENTRY_TYPE_R3;
} else if (likely(pte_present(pte)))
rste |= _SEGMENT_ENTRY_LARGE;
clear_huge_pte_skeys(mm, rste);
set_pte(ptep, __pte(rste));
}
void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, unsigned long sz)
{
__set_huge_pte_at(mm, addr, ptep, pte);
}
pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, 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(mm, addr, 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, struct vm_area_struct *vma,
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 (sz == PUD_SIZE)
return (pte_t *)pudp;
if (pud_present(*pudp))
pmdp = pmd_offset(pudp, addr);
}
}
return (pte_t *) pmdp;
}
bool __init arch_hugetlb_valid_size(unsigned long size)
{
if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
return true;
else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE)
return true;
else
return false;
}