linux-zen-desktop/arch/um/include/asm/pgtable.h

341 lines
9.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Copyright 2003 PathScale, Inc.
* Derived from include/asm-i386/pgtable.h
*/
#ifndef __UM_PGTABLE_H
#define __UM_PGTABLE_H
#include <asm/fixmap.h>
#define _PAGE_PRESENT 0x001
#define _PAGE_NEWPAGE 0x002
#define _PAGE_NEWPROT 0x004
#define _PAGE_RW 0x020
#define _PAGE_USER 0x040
#define _PAGE_ACCESSED 0x080
#define _PAGE_DIRTY 0x100
/* If _PAGE_PRESENT is clear, we use these: */
#define _PAGE_PROTNONE 0x010 /* if the user mapped it with PROT_NONE;
pte_present gives true */
/* We borrow bit 10 to store the exclusive marker in swap PTEs. */
#define _PAGE_SWP_EXCLUSIVE 0x400
#ifdef CONFIG_3_LEVEL_PGTABLES
#include <asm/pgtable-3level.h>
#else
#include <asm/pgtable-2level.h>
#endif
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
/* zero page used for uninitialized stuff */
extern unsigned long *empty_zero_page;
/* Just any arbitrary offset to the start of the vmalloc VM area: the
* current 8MB value just means that there will be a 8MB "hole" after the
* physical memory until the kernel virtual memory starts. That means that
* any out-of-bounds memory accesses will hopefully be caught.
* The vmalloc() routines leaves a hole of 4kB between each vmalloced
* area for the same reason. ;)
*/
extern unsigned long end_iomem;
#define VMALLOC_OFFSET (__va_space)
#define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
#define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
#define MODULES_VADDR VMALLOC_START
#define MODULES_END VMALLOC_END
#define MODULES_LEN (MODULES_VADDR - MODULES_END)
#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define __PAGE_KERNEL_EXEC \
(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
#define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC)
/*
* The i386 can't do page protection for execute, and considers that the same
* are read.
* Also, write permissions imply read permissions. This is the closest we can
* get..
*/
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
#define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
#define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
#define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
#define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
#define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE)
#define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE)
#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
#define pte_page(x) pfn_to_page(pte_pfn(x))
#define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
/*
* =================================
* Flags checking section.
* =================================
*/
static inline int pte_none(pte_t pte)
{
return pte_is_zero(pte);
}
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
static inline int pte_read(pte_t pte)
{
return((pte_get_bits(pte, _PAGE_USER)) &&
!(pte_get_bits(pte, _PAGE_PROTNONE)));
}
static inline int pte_exec(pte_t pte){
return((pte_get_bits(pte, _PAGE_USER)) &&
!(pte_get_bits(pte, _PAGE_PROTNONE)));
}
static inline int pte_write(pte_t pte)
{
return((pte_get_bits(pte, _PAGE_RW)) &&
!(pte_get_bits(pte, _PAGE_PROTNONE)));
}
static inline int pte_dirty(pte_t pte)
{
return pte_get_bits(pte, _PAGE_DIRTY);
}
static inline int pte_young(pte_t pte)
{
return pte_get_bits(pte, _PAGE_ACCESSED);
}
static inline int pte_newpage(pte_t pte)
{
return pte_get_bits(pte, _PAGE_NEWPAGE);
}
static inline int pte_newprot(pte_t pte)
{
return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
}
/*
* =================================
* Flags setting section.
* =================================
*/
static inline pte_t pte_mknewprot(pte_t pte)
{
pte_set_bits(pte, _PAGE_NEWPROT);
return(pte);
}
static inline pte_t pte_mkclean(pte_t pte)
{
pte_clear_bits(pte, _PAGE_DIRTY);
return(pte);
}
static inline pte_t pte_mkold(pte_t pte)
{
pte_clear_bits(pte, _PAGE_ACCESSED);
return(pte);
}
static inline pte_t pte_wrprotect(pte_t pte)
{
if (likely(pte_get_bits(pte, _PAGE_RW)))
pte_clear_bits(pte, _PAGE_RW);
else
return pte;
return(pte_mknewprot(pte));
}
static inline pte_t pte_mkread(pte_t pte)
{
if (unlikely(pte_get_bits(pte, _PAGE_USER)))
return pte;
pte_set_bits(pte, _PAGE_USER);
return(pte_mknewprot(pte));
}
static inline pte_t pte_mkdirty(pte_t pte)
{
pte_set_bits(pte, _PAGE_DIRTY);
return(pte);
}
static inline pte_t pte_mkyoung(pte_t pte)
{
pte_set_bits(pte, _PAGE_ACCESSED);
return(pte);
}
static inline pte_t pte_mkwrite(pte_t pte)
{
if (unlikely(pte_get_bits(pte, _PAGE_RW)))
return pte;
pte_set_bits(pte, _PAGE_RW);
return(pte_mknewprot(pte));
}
static inline pte_t pte_mkuptodate(pte_t pte)
{
pte_clear_bits(pte, _PAGE_NEWPAGE);
if(pte_present(pte))
pte_clear_bits(pte, _PAGE_NEWPROT);
return(pte);
}
static inline pte_t pte_mknewpage(pte_t pte)
{
pte_set_bits(pte, _PAGE_NEWPAGE);
return(pte);
}
static inline void set_pte(pte_t *pteptr, pte_t pteval)
{
pte_copy(*pteptr, pteval);
/* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
* fix_range knows to unmap it. _PAGE_NEWPROT is specific to
* mapped pages.
*/
*pteptr = pte_mknewpage(*pteptr);
if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
}
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *pteptr, pte_t pteval)
{
set_pte(pteptr, pteval);
}
#define __HAVE_ARCH_PTE_SAME
static inline int pte_same(pte_t pte_a, pte_t pte_b)
{
return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
}
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*/
#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
#define __virt_to_page(virt) phys_to_page(__pa(virt))
#define page_to_phys(page) pfn_to_phys(page_to_pfn(page))
#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
#define mk_pte(page, pgprot) \
({ pte_t pte; \
\
pte_set_val(pte, page_to_phys(page), (pgprot)); \
if (pte_present(pte)) \
pte_mknewprot(pte_mknewpage(pte)); \
pte;})
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
return pte;
}
/*
* the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
*
* this macro returns the index of the entry in the pmd page which would
* control the given virtual address
*/
#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
struct mm_struct;
extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
#define update_mmu_cache(vma,address,ptep) do {} while (0)
/*
* Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
* are !pte_none() && !pte_present().
*
* Format of swap PTEs:
*
* 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
* <--------------- offset ----------------> E < type -> 0 0 0 1 0
*
* E is the exclusive marker that is not stored in swap entries.
* _PAGE_NEWPAGE (bit 1) is always set to 1 in set_pte().
*/
#define __swp_type(x) (((x).val >> 5) & 0x1f)
#define __swp_offset(x) ((x).val >> 11)
#define __swp_entry(type, offset) \
((swp_entry_t) { (((type) & 0x1f) << 5) | ((offset) << 11) })
#define __pte_to_swp_entry(pte) \
((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
static inline int pte_swp_exclusive(pte_t pte)
{
return pte_get_bits(pte, _PAGE_SWP_EXCLUSIVE);
}
static inline pte_t pte_swp_mkexclusive(pte_t pte)
{
pte_set_bits(pte, _PAGE_SWP_EXCLUSIVE);
return pte;
}
static inline pte_t pte_swp_clear_exclusive(pte_t pte)
{
pte_clear_bits(pte, _PAGE_SWP_EXCLUSIVE);
return pte;
}
/* 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((vaddr)); \
} while (0)
#endif