mirror of https://gitee.com/openkylin/linux.git
114 lines
3.1 KiB
C
114 lines
3.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_PGTABLE_32_H
|
|
#define _ASM_X86_PGTABLE_32_H
|
|
|
|
#include <asm/pgtable_32_types.h>
|
|
|
|
/*
|
|
* The Linux memory management assumes a three-level page table setup. On
|
|
* the i386, we use that, but "fold" the mid level into the top-level page
|
|
* table, so that we physically have the same two-level page table as the
|
|
* i386 mmu expects.
|
|
*
|
|
* This file contains the functions and defines necessary to modify and use
|
|
* the i386 page table tree.
|
|
*/
|
|
#ifndef __ASSEMBLY__
|
|
#include <asm/processor.h>
|
|
#include <linux/threads.h>
|
|
#include <asm/paravirt.h>
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/list.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
struct mm_struct;
|
|
struct vm_area_struct;
|
|
|
|
extern pgd_t swapper_pg_dir[1024];
|
|
extern pgd_t initial_page_table[1024];
|
|
extern pmd_t initial_pg_pmd[];
|
|
|
|
static inline void pgtable_cache_init(void) { }
|
|
static inline void check_pgt_cache(void) { }
|
|
void paging_init(void);
|
|
void sync_initial_page_table(void);
|
|
|
|
static inline int pgd_large(pgd_t pgd) { return 0; }
|
|
|
|
/*
|
|
* Define this if things work differently on an i386 and an i486:
|
|
* it will (on an i486) warn about kernel memory accesses that are
|
|
* done without a 'access_ok(VERIFY_WRITE,..)'
|
|
*/
|
|
#undef TEST_ACCESS_OK
|
|
|
|
#ifdef CONFIG_X86_PAE
|
|
# include <asm/pgtable-3level.h>
|
|
#else
|
|
# include <asm/pgtable-2level.h>
|
|
#endif
|
|
|
|
#if defined(CONFIG_HIGHPTE)
|
|
#define pte_offset_map(dir, address) \
|
|
((pte_t *)kmap_atomic(pmd_page(*(dir))) + \
|
|
pte_index((address)))
|
|
#define pte_unmap(pte) kunmap_atomic((pte))
|
|
#else
|
|
#define pte_offset_map(dir, address) \
|
|
((pte_t *)page_address(pmd_page(*(dir))) + pte_index((address)))
|
|
#define pte_unmap(pte) do { } while (0)
|
|
#endif
|
|
|
|
/* Clear a kernel PTE and flush it from the TLB */
|
|
#define kpte_clear_flush(ptep, vaddr) \
|
|
do { \
|
|
pte_clear(&init_mm, (vaddr), (ptep)); \
|
|
__flush_tlb_one_kernel((vaddr)); \
|
|
} while (0)
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
/*
|
|
* kern_addr_valid() is (1) for FLATMEM and (0) for
|
|
* SPARSEMEM and DISCONTIGMEM
|
|
*/
|
|
#ifdef CONFIG_FLATMEM
|
|
#define kern_addr_valid(addr) (1)
|
|
#else
|
|
#define kern_addr_valid(kaddr) (0)
|
|
#endif
|
|
|
|
/*
|
|
* This is how much memory in addition to the memory covered up to
|
|
* and including _end we need mapped initially.
|
|
* We need:
|
|
* (KERNEL_IMAGE_SIZE/4096) / 1024 pages (worst case, non PAE)
|
|
* (KERNEL_IMAGE_SIZE/4096) / 512 + 4 pages (worst case for PAE)
|
|
*
|
|
* Modulo rounding, each megabyte assigned here requires a kilobyte of
|
|
* memory, which is currently unreclaimed.
|
|
*
|
|
* This should be a multiple of a page.
|
|
*
|
|
* KERNEL_IMAGE_SIZE should be greater than pa(_end)
|
|
* and small than max_low_pfn, otherwise will waste some page table entries
|
|
*/
|
|
#if PTRS_PER_PMD > 1
|
|
#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
|
|
#else
|
|
#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
|
|
#endif
|
|
|
|
/*
|
|
* Number of possible pages in the lowmem region.
|
|
*
|
|
* We shift 2 by 31 instead of 1 by 32 to the left in order to avoid a
|
|
* gas warning about overflowing shift count when gas has been compiled
|
|
* with only a host target support using a 32-bit type for internal
|
|
* representation.
|
|
*/
|
|
#define LOWMEM_PAGES ((((2<<31) - __PAGE_OFFSET) >> PAGE_SHIFT))
|
|
|
|
#endif /* _ASM_X86_PGTABLE_32_H */
|