linux/arch/s390/include/asm/pgalloc.h
Martin Schwidefsky 1aea9b3f92 s390/mm: implement 5 level pages tables
Add the logic to upgrade the page table for a 64-bit process to
five levels. This increases the TASK_SIZE from 8PB to 16EB-4K.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:54 +02:00

161 lines
4.3 KiB
C

/*
* S390 version
* Copyright IBM Corp. 1999, 2000
* Author(s): Hartmut Penner (hp@de.ibm.com)
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "include/asm-i386/pgalloc.h"
* Copyright (C) 1994 Linus Torvalds
*/
#ifndef _S390_PGALLOC_H
#define _S390_PGALLOC_H
#include <linux/threads.h>
#include <linux/gfp.h>
#include <linux/mm.h>
unsigned long *crst_table_alloc(struct mm_struct *);
void crst_table_free(struct mm_struct *, unsigned long *);
unsigned long *page_table_alloc(struct mm_struct *);
struct page *page_table_alloc_pgste(struct mm_struct *mm);
void page_table_free(struct mm_struct *, unsigned long *);
void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
void page_table_free_pgste(struct page *page);
extern int page_table_allocate_pgste;
static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
{
struct addrtype { char _[256]; };
int i;
for (i = 0; i < n; i += 256) {
*s = val;
asm volatile(
"mvc 8(248,%[s]),0(%[s])\n"
: "+m" (*(struct addrtype *) s)
: [s] "a" (s));
s += 256 / sizeof(long);
}
}
static inline void crst_table_init(unsigned long *crst, unsigned long entry)
{
clear_table(crst, entry, sizeof(unsigned long)*2048);
}
static inline unsigned long pgd_entry_type(struct mm_struct *mm)
{
if (mm->context.asce_limit <= (1UL << 31))
return _SEGMENT_ENTRY_EMPTY;
if (mm->context.asce_limit <= (1UL << 42))
return _REGION3_ENTRY_EMPTY;
if (mm->context.asce_limit <= (1UL << 53))
return _REGION2_ENTRY_EMPTY;
return _REGION1_ENTRY_EMPTY;
}
int crst_table_upgrade(struct mm_struct *mm, unsigned long limit);
void crst_table_downgrade(struct mm_struct *);
static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address)
{
unsigned long *table = crst_table_alloc(mm);
if (table)
crst_table_init(table, _REGION2_ENTRY_EMPTY);
return (p4d_t *) table;
}
#define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d)
static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
{
unsigned long *table = crst_table_alloc(mm);
if (table)
crst_table_init(table, _REGION3_ENTRY_EMPTY);
return (pud_t *) table;
}
#define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
{
unsigned long *table = crst_table_alloc(mm);
if (!table)
return NULL;
crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
crst_table_free(mm, table);
return NULL;
}
return (pmd_t *) table;
}
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
pgtable_pmd_page_dtor(virt_to_page(pmd));
crst_table_free(mm, (unsigned long *) pmd);
}
static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
{
pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
}
static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
{
p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
}
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
}
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
unsigned long *table = crst_table_alloc(mm);
if (!table)
return NULL;
if (mm->context.asce_limit == (1UL << 31)) {
/* Forking a compat process with 2 page table levels */
if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
crst_table_free(mm, table);
return NULL;
}
}
return (pgd_t *) table;
}
static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
if (mm->context.asce_limit == (1UL << 31))
pgtable_pmd_page_dtor(virt_to_page(pgd));
crst_table_free(mm, (unsigned long *) pgd);
}
static inline void pmd_populate(struct mm_struct *mm,
pmd_t *pmd, pgtable_t pte)
{
pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
}
#define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
#define pmd_pgtable(pmd) \
(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
/*
* page table entry allocation/free routines.
*/
#define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
#define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
#define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
#define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
extern void rcu_table_freelist_finish(void);
#endif /* _S390_PGALLOC_H */