forked from Minki/linux
d455a3696c
Replace misleading definition of FIRST_USER_PGD_NR 0 by definition of FIRST_USER_ADDRESS 0 in all the MMU architectures beyond arm and arm26. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
353 lines
11 KiB
C
353 lines
11 KiB
C
/*
|
|
* CRIS pgtable.h - macros and functions to manipulate page tables.
|
|
*/
|
|
|
|
#ifndef _CRIS_PGTABLE_H
|
|
#define _CRIS_PGTABLE_H
|
|
|
|
#include <asm-generic/4level-fixup.h>
|
|
|
|
#ifndef __ASSEMBLY__
|
|
#include <linux/config.h>
|
|
#include <linux/sched.h>
|
|
#include <asm/mmu.h>
|
|
#endif
|
|
#include <asm/arch/pgtable.h>
|
|
|
|
/*
|
|
* The Linux memory management assumes a three-level page table setup. On
|
|
* CRIS, we use that, but "fold" the mid level into the top-level page
|
|
* table. Since the MMU TLB is software loaded through an interrupt, it
|
|
* supports any page table structure, so we could have used a three-level
|
|
* setup, but for the amounts of memory we normally use, a two-level is
|
|
* probably more efficient.
|
|
*
|
|
* This file contains the functions and defines necessary to modify and use
|
|
* the CRIS page table tree.
|
|
*/
|
|
#ifndef __ASSEMBLY__
|
|
extern void paging_init(void);
|
|
#endif
|
|
|
|
/* Certain architectures need to do special things when pte's
|
|
* within a page table are directly modified. Thus, the following
|
|
* hook is made available.
|
|
*/
|
|
#define set_pte(pteptr, pteval) ((*(pteptr)) = (pteval))
|
|
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
|
|
|
|
/*
|
|
* (pmds are folded into pgds so this doesn't get actually called,
|
|
* but the define is needed for a generic inline function.)
|
|
*/
|
|
#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
|
|
#define set_pgd(pgdptr, pgdval) (*(pgdptr) = pgdval)
|
|
|
|
/* PMD_SHIFT determines the size of the area a second-level page table can
|
|
* map. It is equal to the page size times the number of PTE's that fit in
|
|
* a PMD page. A PTE is 4-bytes in CRIS. Hence the following number.
|
|
*/
|
|
|
|
#define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT-2))
|
|
#define PMD_SIZE (1UL << PMD_SHIFT)
|
|
#define PMD_MASK (~(PMD_SIZE-1))
|
|
|
|
/* PGDIR_SHIFT determines what a third-level page table entry can map.
|
|
* Since we fold into a two-level structure, this is the same as PMD_SHIFT.
|
|
*/
|
|
|
|
#define PGDIR_SHIFT PMD_SHIFT
|
|
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
|
|
#define PGDIR_MASK (~(PGDIR_SIZE-1))
|
|
|
|
/*
|
|
* entries per page directory level: we use a two-level, so
|
|
* we don't really have any PMD directory physically.
|
|
* pointers are 4 bytes so we can use the page size and
|
|
* divide it by 4 (shift by 2).
|
|
*/
|
|
#define PTRS_PER_PTE (1UL << (PAGE_SHIFT-2))
|
|
#define PTRS_PER_PMD 1
|
|
#define PTRS_PER_PGD (1UL << (PAGE_SHIFT-2))
|
|
|
|
/* calculate how many PGD entries a user-level program can use
|
|
* the first mappable virtual address is 0
|
|
* (TASK_SIZE is the maximum virtual address space)
|
|
*/
|
|
|
|
#define USER_PTRS_PER_PGD (TASK_SIZE/PGDIR_SIZE)
|
|
#define FIRST_USER_ADDRESS 0
|
|
|
|
/* zero page used for uninitialized stuff */
|
|
#ifndef __ASSEMBLY__
|
|
extern unsigned long empty_zero_page;
|
|
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
|
|
#endif
|
|
|
|
/* number of bits that fit into a memory pointer */
|
|
#define BITS_PER_PTR (8*sizeof(unsigned long))
|
|
|
|
/* to align the pointer to a pointer address */
|
|
#define PTR_MASK (~(sizeof(void*)-1))
|
|
|
|
/* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
|
|
/* 64-bit machines, beware! SRB. */
|
|
#define SIZEOF_PTR_LOG2 2
|
|
|
|
/* to find an entry in a page-table */
|
|
#define PAGE_PTR(address) \
|
|
((unsigned long)(address)>>(PAGE_SHIFT-SIZEOF_PTR_LOG2)&PTR_MASK&~PAGE_MASK)
|
|
|
|
/* to set the page-dir */
|
|
#define SET_PAGE_DIR(tsk,pgdir)
|
|
|
|
#define pte_none(x) (!pte_val(x))
|
|
#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
|
|
#define pte_clear(mm,addr,xp) do { pte_val(*(xp)) = 0; } while (0)
|
|
|
|
#define pmd_none(x) (!pmd_val(x))
|
|
/* by removing the _PAGE_KERNEL bit from the comparision, the same pmd_bad
|
|
* works for both _PAGE_TABLE and _KERNPG_TABLE pmd entries.
|
|
*/
|
|
#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_KERNEL)) != _PAGE_TABLE)
|
|
#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
|
|
#define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0)
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
/*
|
|
* The "pgd_xxx()" functions here are trivial for a folded two-level
|
|
* setup: the pgd is never bad, and a pmd always exists (as it's folded
|
|
* into the pgd entry)
|
|
*/
|
|
extern inline int pgd_none(pgd_t pgd) { return 0; }
|
|
extern inline int pgd_bad(pgd_t pgd) { return 0; }
|
|
extern inline int pgd_present(pgd_t pgd) { return 1; }
|
|
extern inline void pgd_clear(pgd_t * pgdp) { }
|
|
|
|
/*
|
|
* The following only work if pte_present() is true.
|
|
* Undefined behaviour if not..
|
|
*/
|
|
|
|
extern inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_READ; }
|
|
extern inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
|
|
extern inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_READ; }
|
|
extern inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_MODIFIED; }
|
|
extern inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
|
|
extern inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
|
|
|
|
extern inline pte_t pte_wrprotect(pte_t pte)
|
|
{
|
|
pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_rdprotect(pte_t pte)
|
|
{
|
|
pte_val(pte) &= ~(_PAGE_READ | _PAGE_SILENT_READ);
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_exprotect(pte_t pte)
|
|
{
|
|
pte_val(pte) &= ~(_PAGE_READ | _PAGE_SILENT_READ);
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkclean(pte_t pte)
|
|
{
|
|
pte_val(pte) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkold(pte_t pte)
|
|
{
|
|
pte_val(pte) &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkwrite(pte_t pte)
|
|
{
|
|
pte_val(pte) |= _PAGE_WRITE;
|
|
if (pte_val(pte) & _PAGE_MODIFIED)
|
|
pte_val(pte) |= _PAGE_SILENT_WRITE;
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkread(pte_t pte)
|
|
{
|
|
pte_val(pte) |= _PAGE_READ;
|
|
if (pte_val(pte) & _PAGE_ACCESSED)
|
|
pte_val(pte) |= _PAGE_SILENT_READ;
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkexec(pte_t pte)
|
|
{
|
|
pte_val(pte) |= _PAGE_READ;
|
|
if (pte_val(pte) & _PAGE_ACCESSED)
|
|
pte_val(pte) |= _PAGE_SILENT_READ;
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkdirty(pte_t pte)
|
|
{
|
|
pte_val(pte) |= _PAGE_MODIFIED;
|
|
if (pte_val(pte) & _PAGE_WRITE)
|
|
pte_val(pte) |= _PAGE_SILENT_WRITE;
|
|
return pte;
|
|
}
|
|
|
|
extern inline pte_t pte_mkyoung(pte_t pte)
|
|
{
|
|
pte_val(pte) |= _PAGE_ACCESSED;
|
|
if (pte_val(pte) & _PAGE_READ)
|
|
{
|
|
pte_val(pte) |= _PAGE_SILENT_READ;
|
|
if ((pte_val(pte) & (_PAGE_WRITE | _PAGE_MODIFIED)) ==
|
|
(_PAGE_WRITE | _PAGE_MODIFIED))
|
|
pte_val(pte) |= _PAGE_SILENT_WRITE;
|
|
}
|
|
return pte;
|
|
}
|
|
|
|
/*
|
|
* Conversion functions: convert a page and protection to a page entry,
|
|
* and a page entry and page directory to the page they refer to.
|
|
*/
|
|
|
|
/* What actually goes as arguments to the various functions is less than
|
|
* obvious, but a rule of thumb is that struct page's goes as struct page *,
|
|
* really physical DRAM addresses are unsigned long's, and DRAM "virtual"
|
|
* addresses (the 0xc0xxxxxx's) goes as void *'s.
|
|
*/
|
|
|
|
extern inline pte_t __mk_pte(void * page, pgprot_t pgprot)
|
|
{
|
|
pte_t pte;
|
|
/* the PTE needs a physical address */
|
|
pte_val(pte) = __pa(page) | pgprot_val(pgprot);
|
|
return pte;
|
|
}
|
|
|
|
#define mk_pte(page, pgprot) __mk_pte(page_address(page), (pgprot))
|
|
|
|
#define mk_pte_phys(physpage, pgprot) \
|
|
({ \
|
|
pte_t __pte; \
|
|
\
|
|
pte_val(__pte) = (physpage) + pgprot_val(pgprot); \
|
|
__pte; \
|
|
})
|
|
|
|
extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
|
|
{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
|
|
|
|
|
|
/* pte_val refers to a page in the 0x4xxxxxxx physical DRAM interval
|
|
* __pte_page(pte_val) refers to the "virtual" DRAM interval
|
|
* pte_pagenr refers to the page-number counted starting from the virtual DRAM start
|
|
*/
|
|
|
|
extern inline unsigned long __pte_page(pte_t pte)
|
|
{
|
|
/* the PTE contains a physical address */
|
|
return (unsigned long)__va(pte_val(pte) & PAGE_MASK);
|
|
}
|
|
|
|
#define pte_pagenr(pte) ((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)
|
|
|
|
/* permanent address of a page */
|
|
|
|
#define __page_address(page) (PAGE_OFFSET + (((page) - mem_map) << PAGE_SHIFT))
|
|
#define pte_page(pte) (mem_map+pte_pagenr(pte))
|
|
|
|
/* only the pte's themselves need to point to physical DRAM (see above)
|
|
* the pagetable links are purely handled within the kernel SW and thus
|
|
* don't need the __pa and __va transformations.
|
|
*/
|
|
|
|
extern inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
|
|
{ pmd_val(*pmdp) = _PAGE_TABLE | (unsigned long) ptep; }
|
|
|
|
#define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
|
|
#define pmd_page_kernel(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
|
|
|
|
/* to find an entry in a page-table-directory. */
|
|
#define pgd_index(address) ((address >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
|
|
|
|
/* to find an entry in a page-table-directory */
|
|
extern inline pgd_t * pgd_offset(struct mm_struct * mm, unsigned long address)
|
|
{
|
|
return mm->pgd + pgd_index(address);
|
|
}
|
|
|
|
/* to find an entry in a kernel page-table-directory */
|
|
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
|
|
|
|
/* Find an entry in the second-level page table.. */
|
|
extern inline pmd_t * pmd_offset(pgd_t * dir, unsigned long address)
|
|
{
|
|
return (pmd_t *) dir;
|
|
}
|
|
|
|
/* Find an entry in the third-level page table.. */
|
|
#define __pte_offset(address) \
|
|
(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
|
|
#define pte_offset_kernel(dir, address) \
|
|
((pte_t *) pmd_page_kernel(*(dir)) + __pte_offset(address))
|
|
#define pte_offset_map(dir, address) \
|
|
((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
|
|
#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
|
|
|
|
#define pte_unmap(pte) do { } while (0)
|
|
#define pte_unmap_nested(pte) do { } while (0)
|
|
#define pte_pfn(x) ((unsigned long)(__va((x).pte)) >> PAGE_SHIFT)
|
|
#define pfn_pte(pfn, prot) __pte((__pa((pfn) << PAGE_SHIFT)) | pgprot_val(prot))
|
|
|
|
#define pte_ERROR(e) \
|
|
printk("%s:%d: bad pte %p(%08lx).\n", __FILE__, __LINE__, &(e), pte_val(e))
|
|
#define pmd_ERROR(e) \
|
|
printk("%s:%d: bad pmd %p(%08lx).\n", __FILE__, __LINE__, &(e), pmd_val(e))
|
|
#define pgd_ERROR(e) \
|
|
printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), pgd_val(e))
|
|
|
|
|
|
extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */
|
|
|
|
/*
|
|
* CRIS doesn't have any external MMU info: the kernel page
|
|
* tables contain all the necessary information.
|
|
*
|
|
* Actually I am not sure on what this could be used for.
|
|
*/
|
|
extern inline void update_mmu_cache(struct vm_area_struct * vma,
|
|
unsigned long address, pte_t pte)
|
|
{
|
|
}
|
|
|
|
/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */
|
|
/* Since the PAGE_PRESENT bit is bit 4, we can use the bits above */
|
|
|
|
#define __swp_type(x) (((x).val >> 5) & 0x7f)
|
|
#define __swp_offset(x) ((x).val >> 12)
|
|
#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 5) | ((offset) << 12) })
|
|
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
|
|
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
|
|
|
|
#define kern_addr_valid(addr) (1)
|
|
|
|
#include <asm-generic/pgtable.h>
|
|
|
|
/*
|
|
* No page table caches to initialise
|
|
*/
|
|
#define pgtable_cache_init() do { } while (0)
|
|
|
|
#define pte_to_pgoff(x) (pte_val(x) >> 6)
|
|
#define pgoff_to_pte(x) __pte(((x) << 6) | _PAGE_FILE)
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
#endif /* _CRIS_PGTABLE_H */
|