blob: 3de42e776274e1436a18417202326eab98130277 (
plain)
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
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
/*
* highmem.h: virtual kernel memory mappings for high memory
*
* Used in CONFIG_HIGHMEM systems for memory pages which
* are not addressable by direct kernel virtual addresses.
*
* Copyright (C) 1999 Gerhard Wichert, Siemens AG
* Gerhard.Wichert@pdb.siemens.de
*
*
* Redesigned the x86 32-bit VM architecture to deal with
* up to 16 Terrabyte physical memory. With current x86 CPUs
* we now support up to 64 Gigabytes physical RAM.
*
* Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
*/
#ifndef _ASM_HIGHMEM_H
#define _ASM_HIGHMEM_H
#ifdef __KERNEL__
#include <linux/interrupt.h>
#include <asm/fixmap.h>
#include <asm/vaddrs.h>
#include <asm/kmap_types.h>
#include <asm/pgtable.h>
/* declarations for highmem.c */
extern unsigned long highstart_pfn, highend_pfn;
extern pte_t *kmap_pte;
extern pgprot_t kmap_prot;
extern pte_t *pkmap_page_table;
extern void kmap_init(void) __init;
/*
* Right now we initialize only a single pte table. It can be extended
* easily, subsequent pte tables have to be allocated in one physical
* chunk of RAM. Currently the simplest way to do this is to align the
* pkmap region on a pagetable boundary (4MB).
*/
#define LAST_PKMAP 1024
#define PKMAP_SIZE (LAST_PKMAP << PAGE_SHIFT)
#define PKMAP_BASE PMD_ALIGN(SRMMU_NOCACHE_VADDR + (SRMMU_MAX_NOCACHE_PAGES << PAGE_SHIFT))
#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
#define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
#define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);
static inline void *kmap(struct page *page)
{
BUG_ON(in_interrupt());
if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
}
static inline void kunmap(struct page *page)
{
BUG_ON(in_interrupt());
if (!PageHighMem(page))
return;
kunmap_high(page);
}
extern void *kmap_atomic(struct page *page, enum km_type type);
extern void kunmap_atomic(void *kvaddr, enum km_type type);
extern struct page *kmap_atomic_to_page(void *vaddr);
#define flush_cache_kmaps() flush_cache_all()
#endif /* __KERNEL__ */
#endif /* _ASM_HIGHMEM_H */
|
