270 lines
7.5 KiB
C
270 lines
7.5 KiB
C
// 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);
|