65 строки
1.4 KiB
C
65 строки
1.4 KiB
C
|
/*
|
||
|
|
* arch/sh/mm/kmap.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)
|
||
|
|
{
|
||
|
|
unsigned long vaddr;
|
||
|
|
|
||
|
|
if (!boot_cpu_data.dcache.n_aliases)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* cache the first coherent kmap pte */
|
||
|
|
vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
|
||
|
|
kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
|
||
|
|
}
|
||
|
|
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
|
||
|
|
void kunmap_coherent(void)
|
||
|
|
{
|
||
|
|
dec_preempt_count();
|
||
|
|
preempt_check_resched();
|
||
|
|
}
|