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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2003 Ralf Baechle
*/
#ifndef _ASM_PGTABLE_H
#define _ASM_PGTABLE_H
#include <linux/mm_types.h>
#include <linux/mmzone.h>
#ifdef CONFIG_32BIT
#include <asm/pgtable-32.h>
#endif
#ifdef CONFIG_64BIT
#include <asm/pgtable-64.h>
#endif
#include <asm/io.h>
#include <asm/pgtable-bits.h>
struct mm_struct;
struct vm_area_struct;
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
_page_cachable_default)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
_page_cachable_default)
#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \
_page_cachable_default)
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | \
_page_cachable_default)
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
_PAGE_GLOBAL | _page_cachable_default)
#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
_PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
_page_cachable_default)
#define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
__WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
/*
* If _PAGE_NO_EXEC is not defined, we can't do page protection for
* execute, and consider it to be the same as read. Also, write
* permissions imply read permissions. This is the closest we can get
* by reasonable means..
*/
/*
* Dummy values to fill the table in mmap.c
* The real values will be generated at runtime
*/
#define __P000 __pgprot(0)
#define __P001 __pgprot(0)
#define __P010 __pgprot(0)
#define __P011 __pgprot(0)
#define __P100 __pgprot(0)
#define __P101 __pgprot(0)
#define __P110 __pgprot(0)
#define __P111 __pgprot(0)
#define __S000 __pgprot(0)
#define __S001 __pgprot(0)
#define __S010 __pgprot(0)
#define __S011 __pgprot(0)
#define __S100 __pgprot(0)
#define __S101 __pgprot(0)
#define __S110 __pgprot(0)
#define __S111 __pgprot(0)
extern unsigned long _page_cachable_default;
/*
* ZERO_PAGE is a global shared page that is always zero; used
* for zero-mapped memory areas etc..
*/
extern unsigned long empty_zero_page;
extern unsigned long zero_page_mask;
#define ZERO_PAGE(vaddr) \
(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
#define __HAVE_COLOR_ZERO_PAGE
extern void paging_init(void);
/*
* 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 pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd))
#define __pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
#ifndef CONFIG_TRANSPARENT_HUGEPAGE
#define pmd_page(pmd) __pmd_page(pmd)
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#define pmd_page_vaddr(pmd) pmd_val(pmd)
#define htw_stop() \
do { \
unsigned long flags; \
\
if (cpu_has_htw) { \
local_irq_save(flags); \
if(!raw_current_cpu_data.htw_seq++) { \
write_c0_pwctl(read_c0_pwctl() & \
~(1 << MIPS_PWCTL_PWEN_SHIFT)); \
back_to_back_c0_hazard(); \
} \
local_irq_restore(flags); \
} \
} while(0)
#define htw_start() \
do { \
unsigned long flags; \
\
if (cpu_has_htw) { \
local_irq_save(flags); \
if (!--raw_current_cpu_data.htw_seq) { \
write_c0_pwctl(read_c0_pwctl() | \
(1 << MIPS_PWCTL_PWEN_SHIFT)); \
back_to_back_c0_hazard(); \
} \
local_irq_restore(flags); \
} \
} while(0)
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval);
#if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
#ifdef CONFIG_XPA
# define pte_none(pte) (!(((pte).pte_high) & ~_PAGE_GLOBAL))
#else
# define pte_none(pte) (!(((pte).pte_low | (pte).pte_high) & ~_PAGE_GLOBAL))
#endif
#define pte_present(pte) ((pte).pte_low & _PAGE_PRESENT)
#define pte_no_exec(pte) ((pte).pte_low & _PAGE_NO_EXEC)
static inline void set_pte(pte_t *ptep, pte_t pte)
{
ptep->pte_high = pte.pte_high;
smp_wmb();
ptep->pte_low = pte.pte_low;
#ifdef CONFIG_XPA
if (pte.pte_high & _PAGE_GLOBAL) {
#else
if (pte.pte_low & _PAGE_GLOBAL) {
#endif
pte_t *buddy = ptep_buddy(ptep);
/*
* Make sure the buddy is global too (if it's !none,
* it better already be global)
*/
if (pte_none(*buddy)) {
if (!config_enabled(CONFIG_XPA))
buddy->pte_low |= _PAGE_GLOBAL;
buddy->pte_high |= _PAGE_GLOBAL;
}
}
}
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t null = __pte(0);
htw_stop();
/* Preserve global status for the pair */
if (config_enabled(CONFIG_XPA)) {
if (ptep_buddy(ptep)->pte_high & _PAGE_GLOBAL)
null.pte_high = _PAGE_GLOBAL;
} else {
if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL)
null.pte_low = null.pte_high = _PAGE_GLOBAL;
}
set_pte_at(mm, addr, ptep, null);
htw_start();
}
#else
#define pte_none(pte) (!(pte_val(pte) & ~_PAGE_GLOBAL))
#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
#define pte_no_exec(pte) (pte_val(pte) & _PAGE_NO_EXEC)
/*
* Certain architectures need to do special things when pte's
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
static inline void set_pte(pte_t *ptep, pte_t pteval)
{
*ptep = pteval;
#if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
if (pte_val(pteval) & _PAGE_GLOBAL) {
pte_t *buddy = ptep_buddy(ptep);
/*
* Make sure the buddy is global too (if it's !none,
* it better already be global)
*/
#ifdef CONFIG_SMP
/*
* For SMP, multiple CPUs can race, so we need to do
* this atomically.
*/
unsigned long page_global = _PAGE_GLOBAL;
unsigned long tmp;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
__asm__ __volatile__ (
" .set arch=r4000 \n"
" .set push \n"
" .set noreorder \n"
"1:" __LL "%[tmp], %[buddy] \n"
" bnez %[tmp], 2f \n"
" or %[tmp], %[tmp], %[global] \n"
__SC "%[tmp], %[buddy] \n"
" beqzl %[tmp], 1b \n"
" nop \n"
"2: \n"
" .set pop \n"
" .set mips0 \n"
: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
: [global] "r" (page_global));
} else if (kernel_uses_llsc) {
__asm__ __volatile__ (
" .set "MIPS_ISA_ARCH_LEVEL" \n"
" .set push \n"
" .set noreorder \n"
"1:" __LL "%[tmp], %[buddy] \n"
" bnez %[tmp], 2f \n"
" or %[tmp], %[tmp], %[global] \n"
__SC "%[tmp], %[buddy] \n"
" beqz %[tmp], 1b \n"
" nop \n"
"2: \n"
" .set pop \n"
" .set mips0 \n"
: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
: [global] "r" (page_global));
}
#else /* !CONFIG_SMP */
if (pte_none(*buddy))
pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
#endif /* CONFIG_SMP */
}
#endif
}
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
htw_stop();
#if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
/* Preserve global status for the pair */
if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
else
#endif
set_pte_at(mm, addr, ptep, __pte(0));
htw_start();
}
#endif
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
extern void __update_cache(unsigned long address, pte_t pte);
if (!pte_present(pteval))
goto cache_sync_done;
if (pte_present(*ptep) && (pte_pfn(*ptep) == pte_pfn(pteval)))
goto cache_sync_done;
__update_cache(addr, pteval);
cache_sync_done:
set_pte(ptep, pteval);
}
/*
* (pmds are folded into puds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
#ifndef __PAGETABLE_PMD_FOLDED
/*
* (puds are folded into pgds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
#endif
#define PGD_T_LOG2 (__builtin_ffs(sizeof(pgd_t)) - 1)
#define PMD_T_LOG2 (__builtin_ffs(sizeof(pmd_t)) - 1)
#define PTE_T_LOG2 (__builtin_ffs(sizeof(pte_t)) - 1)
/*
* We used to declare this array with size but gcc 3.3 and older are not able
* to find that this expressi
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