mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-09 01:59:41 +00:00
d30e45eeab
This switches the ordering of the Linux vs hardware page tables in each page, thereby eliminating some of the arithmetic in the page table walks. As we now place the Linux page table at the beginning of the page, we can deal with the offset in the pgt by simply masking it away, along with the other control bits. This also makes the arithmetic all be positive, rather than a mixture. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
138 lines
3.1 KiB
C
138 lines
3.1 KiB
C
/*
|
|
* arch/arm/include/asm/pgalloc.h
|
|
*
|
|
* Copyright (C) 2000-2001 Russell King
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef _ASMARM_PGALLOC_H
|
|
#define _ASMARM_PGALLOC_H
|
|
|
|
#include <asm/domain.h>
|
|
#include <asm/pgtable-hwdef.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
#define check_pgt_cache() do { } while (0)
|
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
#define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
|
|
#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
|
|
|
|
/*
|
|
* Since we have only two-level page tables, these are trivial
|
|
*/
|
|
#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
|
|
#define pmd_free(mm, pmd) do { } while (0)
|
|
#define pgd_populate(mm,pmd,pte) BUG()
|
|
|
|
extern pgd_t *pgd_alloc(struct mm_struct *mm);
|
|
extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
|
|
|
|
#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
|
|
|
|
static inline void clean_pte_table(pte_t *pte)
|
|
{
|
|
clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
|
|
}
|
|
|
|
/*
|
|
* Allocate one PTE table.
|
|
*
|
|
* This actually allocates two hardware PTE tables, but we wrap this up
|
|
* into one table thus:
|
|
*
|
|
* +------------+
|
|
* | Linux pt 0 |
|
|
* +------------+
|
|
* | Linux pt 1 |
|
|
* +------------+
|
|
* | h/w pt 0 |
|
|
* +------------+
|
|
* | h/w pt 1 |
|
|
* +------------+
|
|
*/
|
|
static inline pte_t *
|
|
pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
|
|
{
|
|
pte_t *pte;
|
|
|
|
pte = (pte_t *)__get_free_page(PGALLOC_GFP);
|
|
if (pte)
|
|
clean_pte_table(pte);
|
|
|
|
return pte;
|
|
}
|
|
|
|
static inline pgtable_t
|
|
pte_alloc_one(struct mm_struct *mm, unsigned long addr)
|
|
{
|
|
struct page *pte;
|
|
|
|
#ifdef CONFIG_HIGHPTE
|
|
pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
|
|
#else
|
|
pte = alloc_pages(PGALLOC_GFP, 0);
|
|
#endif
|
|
if (pte) {
|
|
if (!PageHighMem(pte))
|
|
clean_pte_table(page_address(pte));
|
|
pgtable_page_ctor(pte);
|
|
}
|
|
|
|
return pte;
|
|
}
|
|
|
|
/*
|
|
* Free one PTE table.
|
|
*/
|
|
static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
|
|
{
|
|
if (pte)
|
|
free_page((unsigned long)pte);
|
|
}
|
|
|
|
static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
|
|
{
|
|
pgtable_page_dtor(pte);
|
|
__free_page(pte);
|
|
}
|
|
|
|
static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
|
|
unsigned long prot)
|
|
{
|
|
unsigned long pmdval = (pte + PTE_HWTABLE_OFF) | prot;
|
|
pmdp[0] = __pmd(pmdval);
|
|
pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
|
|
flush_pmd_entry(pmdp);
|
|
}
|
|
|
|
/*
|
|
* Populate the pmdp entry with a pointer to the pte. This pmd is part
|
|
* of the mm address space.
|
|
*
|
|
* Ensure that we always set both PMD entries.
|
|
*/
|
|
static inline void
|
|
pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
|
|
{
|
|
/*
|
|
* The pmd must be loaded with the physical address of the PTE table
|
|
*/
|
|
__pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
|
|
}
|
|
|
|
static inline void
|
|
pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
|
|
{
|
|
__pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE);
|
|
}
|
|
#define pmd_pgtable(pmd) pmd_page(pmd)
|
|
|
|
#endif /* CONFIG_MMU */
|
|
|
|
#endif
|