101 строка
2.3 KiB
C
101 строка
2.3 KiB
C
/*
|
|
* arch/sh/mm/pg-sh4.c
|
|
*
|
|
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
|
|
* Copyright (C) 2002 - 2007 Paul Mundt
|
|
*
|
|
* Released under the terms of the GNU GPL v2.0.
|
|
*/
|
|
#include <linux/mm.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/fs.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
#define CACHE_ALIAS (current_cpu_data.dcache.alias_mask)
|
|
|
|
static inline void *kmap_coherent(struct page *page, unsigned long addr)
|
|
{
|
|
enum fixed_addresses idx;
|
|
unsigned long vaddr, flags;
|
|
pte_t pte;
|
|
|
|
inc_preempt_count();
|
|
|
|
idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;
|
|
vaddr = __fix_to_virt(FIX_CMAP_END - idx);
|
|
pte = mk_pte(page, PAGE_KERNEL);
|
|
|
|
local_irq_save(flags);
|
|
flush_tlb_one(get_asid(), vaddr);
|
|
local_irq_restore(flags);
|
|
|
|
update_mmu_cache(NULL, vaddr, pte);
|
|
|
|
return (void *)vaddr;
|
|
}
|
|
|
|
static inline void kunmap_coherent(struct page *page)
|
|
{
|
|
dec_preempt_count();
|
|
preempt_check_resched();
|
|
}
|
|
|
|
/*
|
|
* 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 {
|
|
void *vto = kmap_coherent(page, address);
|
|
__clear_user_page(vto, to);
|
|
kunmap_coherent(vto);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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 {
|
|
void *vfrom = kmap_coherent(page, address);
|
|
__copy_user_page(vfrom, from, to);
|
|
kunmap_coherent(vfrom);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|