linux-sg2042/arch/sh/mm/pg-sh4.c

107 lines
2.9 KiB
C

/*
* arch/sh/mm/pg-sh4.c
*
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
* Copyright (C) 2002 - 2005 Paul Mundt
*
* Released under the terms of the GNU GPL v2.0.
*/
#include <linux/mm.h>
#include <linux/mutex.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
extern struct mutex p3map_mutex[];
#define CACHE_ALIAS (current_cpu_data.dcache.alias_mask)
/*
* clear_user_page
* @to: P1 address
* @address: U0 address to be mapped
* @page: page (virt_to_page(to))
*/
void clear_user_page(void *to, unsigned long address, struct page *page)
{
__set_bit(PG_mapped, &page->flags);
if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
clear_page(to);
else {
unsigned long phys_addr = PHYSADDR(to);
unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
pgd_t *pgd = pgd_offset_k(p3_addr);
pud_t *pud = pud_offset(pgd, p3_addr);
pmd_t *pmd = pmd_offset(pud, p3_addr);
pte_t *pte = pte_offset_kernel(pmd, p3_addr);
pte_t entry;
unsigned long flags;
entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL);
mutex_lock(&p3map_mutex[(address & CACHE_ALIAS)>>12]);
set_pte(pte, entry);
local_irq_save(flags);
flush_tlb_one(get_asid(), p3_addr);
local_irq_restore(flags);
update_mmu_cache(NULL, p3_addr, entry);
__clear_user_page((void *)p3_addr, to);
pte_clear(&init_mm, p3_addr, pte);
mutex_unlock(&p3map_mutex[(address & CACHE_ALIAS)>>12]);
}
}
/*
* copy_user_page
* @to: P1 address
* @from: P1 address
* @address: U0 address to be mapped
* @page: page (virt_to_page(to))
*/
void copy_user_page(void *to, void *from, unsigned long address,
struct page *page)
{
__set_bit(PG_mapped, &page->flags);
if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
copy_page(to, from);
else {
unsigned long phys_addr = PHYSADDR(to);
unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
pgd_t *pgd = pgd_offset_k(p3_addr);
pud_t *pud = pud_offset(pgd, p3_addr);
pmd_t *pmd = pmd_offset(pud, p3_addr);
pte_t *pte = pte_offset_kernel(pmd, p3_addr);
pte_t entry;
unsigned long flags;
entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL);
mutex_lock(&p3map_mutex[(address & CACHE_ALIAS)>>12]);
set_pte(pte, entry);
local_irq_save(flags);
flush_tlb_one(get_asid(), p3_addr);
local_irq_restore(flags);
update_mmu_cache(NULL, p3_addr, entry);
__copy_user_page((void *)p3_addr, from, to);
pte_clear(&init_mm, p3_addr, pte);
mutex_unlock(&p3map_mutex[(address & CACHE_ALIAS)>>12]);
}
}
/*
* For SH-4, we have our own implementation for ptep_get_and_clear
*/
inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t pte = *ptep;
pte_clear(mm, addr, ptep);
if (!pte_not_present(pte)) {
unsigned long pfn = pte_pfn(pte);
if (pfn_valid(pfn)) {
struct page *page = pfn_to_page(pfn);
struct address_space *mapping = page_mapping(page);
if (!mapping || !mapping_writably_mapped(mapping))
__clear_bit(PG_mapped, &page->flags);
}
}
return pte;
}