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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/include/asm/pgtable_32.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/pgtable_32.h')
-rw-r--r-- | arch/x86/include/asm/pgtable_32.h | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h new file mode 100644 index 000000000..7c9c968a4 --- /dev/null +++ b/arch/x86/include/asm/pgtable_32.h @@ -0,0 +1,84 @@ +/* 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[]; + +void paging_init(void); +void sync_initial_page_table(void); + +#ifdef CONFIG_X86_PAE +# include <asm/pgtable-3level.h> +#else +# include <asm/pgtable-2level.h> +#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 + */ +#ifdef CONFIG_FLATMEM +#define kern_addr_valid(addr) (1) +#else +#define kern_addr_valid(kaddr) (0) +#endif + +/* + * This is used to calculate the .brk reservation for initial pagetables. + * Enough space is reserved to allocate pagetables sufficient to cover all + * of LOWMEM_PAGES, which is an upper bound on the size of the direct map of + * lowmem. + * + * With PAE paging (PTRS_PER_PMD > 1), we allocate PTRS_PER_PGD == 4 pages for + * the PMD's in addition to the pages required for the last level pagetables. + */ +#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 ((((_ULL(2)<<31) - __PAGE_OFFSET) >> PAGE_SHIFT)) + +#endif /* _ASM_X86_PGTABLE_32_H */ |