1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
/*
* 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();
}
|
