blob: a9ede7bae5203cfe6afb875907d17badc2732d6c [file] [log] [blame]
/*
* arch/sh/mm/pg-mmu.c
*
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
* Copyright (C) 2002 - 2009 Paul Mundt
*
* Released under the terms of the GNU GPL v2.0.
*/
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
#define kmap_get_fixmap_pte(vaddr) \
pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
static pte_t *kmap_coherent_pte;
void __init kmap_coherent_init(void)
{
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
unsigned long vaddr;
/* cache the first coherent kmap pte */
vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
#endif
}
static void *kmap_coherent(struct page *page, unsigned long addr)
{
enum fixed_addresses idx;
unsigned long vaddr, flags;
pte_t pte;
BUG_ON(test_bit(PG_dcache_dirty, &page->flags));
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);
set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
return (void *)vaddr;
}
static inline void kunmap_coherent(void)
{
dec_preempt_count();
preempt_check_resched();
}
void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (boot_cpu_data.dcache.n_aliases && page_mapped(page) &&
!test_bit(PG_dcache_dirty, &page->flags)) {
void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(vto, src, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (boot_cpu_data.dcache.n_aliases)
set_bit(PG_dcache_dirty, &page->flags);
}
if (vma->vm_flags & VM_EXEC)
flush_cache_page(vma, vaddr, page_to_pfn(page));
}
void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (boot_cpu_data.dcache.n_aliases && page_mapped(page) &&
!test_bit(PG_dcache_dirty, &page->flags)) {
void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(dst, vfrom, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (boot_cpu_data.dcache.n_aliases)
set_bit(PG_dcache_dirty, &page->flags);
}
}
void copy_user_highpage(struct page *to, struct page *from,
unsigned long vaddr, struct vm_area_struct *vma)
{
void *vfrom, *vto;
vto = kmap_atomic(to, KM_USER1);
if (boot_cpu_data.dcache.n_aliases && page_mapped(from) &&
!test_bit(PG_dcache_dirty, &from->flags)) {
vfrom = kmap_coherent(from, vaddr);
copy_page(vto, vfrom);
kunmap_coherent();
} else {
vfrom = kmap_atomic(from, KM_USER0);
copy_page(vto, vfrom);
kunmap_atomic(vfrom, KM_USER0);
}
if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
__flush_wback_region(vto, PAGE_SIZE);
kunmap_atomic(vto, KM_USER1);
/* Make sure this page is cleared on other CPU's too before using it */
smp_wmb();
}
EXPORT_SYMBOL(copy_user_highpage);
void clear_user_highpage(struct page *page, unsigned long vaddr)
{
void *kaddr = kmap_atomic(page, KM_USER0);
clear_page(kaddr);
if (pages_do_alias((unsigned long)kaddr, vaddr & PAGE_MASK))
__flush_wback_region(kaddr, PAGE_SIZE);
kunmap_atomic(kaddr, KM_USER0);
}
EXPORT_SYMBOL(clear_user_highpage);
void __update_cache(struct vm_area_struct *vma,
unsigned long address, pte_t pte)
{
struct page *page;
unsigned long pfn = pte_pfn(pte);
if (!boot_cpu_data.dcache.n_aliases)
return;
page = pfn_to_page(pfn);
if (pfn_valid(pfn) && page_mapping(page)) {
int dirty = test_and_clear_bit(PG_dcache_dirty, &page->flags);
if (dirty) {
unsigned long addr = (unsigned long)page_address(page);
if (pages_do_alias(addr, address & PAGE_MASK))
__flush_wback_region((void *)addr, PAGE_SIZE);
}
}
}