1/*
 2 * highmem.h: virtual kernel memory mappings for high memory
 3 *
 4 * Used in CONFIG_HIGHMEM systems for memory pages which
 5 * are not addressable by direct kernel virtual addresses.
 6 *
 7 * Copyright (C) 1999 Gerhard Wichert, Siemens AG
 8 *		      Gerhard.Wichert@pdb.siemens.de
 9 *
10 *
11 * Redesigned the x86 32-bit VM architecture to deal with
12 * up to 16 Terabyte physical memory. With current x86 CPUs
13 * we now support up to 64 Gigabytes physical RAM.
14 *
15 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
16 */
17#ifndef _ASM_HIGHMEM_H
18#define _ASM_HIGHMEM_H
19
20#ifdef __KERNEL__
21
 
22#include <linux/interrupt.h>
23#include <linux/uaccess.h>
24#include <asm/kmap_types.h>
25
26/* undef for production */
27#define HIGHMEM_DEBUG 1
28
29/* declarations for highmem.c */
30extern unsigned long highstart_pfn, highend_pfn;
31
32extern pte_t *pkmap_page_table;
33
34/*
35 * Right now we initialize only a single pte table. It can be extended
36 * easily, subsequent pte tables have to be allocated in one physical
37 * chunk of RAM.
38 */
 
 
 
39#define LAST_PKMAP 1024
 
 
40#define LAST_PKMAP_MASK (LAST_PKMAP-1)
41#define PKMAP_NR(virt)	((virt-PKMAP_BASE) >> PAGE_SHIFT)
42#define PKMAP_ADDR(nr)	(PKMAP_BASE + ((nr) << PAGE_SHIFT))
43
44extern void * kmap_high(struct page *page);
45extern void kunmap_high(struct page *page);
46
47extern void *kmap(struct page *page);
48extern void kunmap(struct page *page);
49extern void *kmap_atomic(struct page *page);
50extern void __kunmap_atomic(void *kvaddr);
51extern void *kmap_atomic_pfn(unsigned long pfn);
52
53#define flush_cache_kmaps()	flush_cache_all()
54
55extern void kmap_init(void);
56
57#define kmap_prot PAGE_KERNEL
 
 
58
59#endif /* __KERNEL__ */
60
61#endif /* _ASM_HIGHMEM_H */

 1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * highmem.h: virtual kernel memory mappings for high memory
 4 *
 5 * Used in CONFIG_HIGHMEM systems for memory pages which
 6 * are not addressable by direct kernel virtual addresses.
 7 *
 8 * Copyright (C) 1999 Gerhard Wichert, Siemens AG
 9 *		      Gerhard.Wichert@pdb.siemens.de
10 *
11 *
12 * Redesigned the x86 32-bit VM architecture to deal with
13 * up to 16 Terabyte physical memory. With current x86 CPUs
14 * we now support up to 64 Gigabytes physical RAM.
15 *
16 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
17 */
18#ifndef _ASM_HIGHMEM_H
19#define _ASM_HIGHMEM_H
20
21#ifdef __KERNEL__
22
23#include <linux/bug.h>
24#include <linux/interrupt.h>
25#include <linux/uaccess.h>
26#include <asm/cpu-features.h>
27#include <asm/kmap_size.h>
 
 
28
29/* declarations for highmem.c */
30extern unsigned long highstart_pfn, highend_pfn;
31
32extern pte_t *pkmap_page_table;
33
34/*
35 * Right now we initialize only a single pte table. It can be extended
36 * easily, subsequent pte tables have to be allocated in one physical
37 * chunk of RAM.
38 */
39#if defined(CONFIG_PHYS_ADDR_T_64BIT) || defined(CONFIG_MIPS_HUGE_TLB_SUPPORT)
40#define LAST_PKMAP 512
41#else
42#define LAST_PKMAP 1024
43#endif
44
45#define LAST_PKMAP_MASK (LAST_PKMAP-1)
46#define PKMAP_NR(virt)	((virt-PKMAP_BASE) >> PAGE_SHIFT)
47#define PKMAP_ADDR(nr)	(PKMAP_BASE + ((nr) << PAGE_SHIFT))
48
49#define ARCH_HAS_KMAP_FLUSH_TLB
50extern void kmap_flush_tlb(unsigned long addr);
 
 
 
 
 
 
 
 
51
52#define flush_cache_kmaps()	BUG_ON(cpu_has_dc_aliases)
53
54#define arch_kmap_local_set_pte(mm, vaddr, ptep, ptev)	set_pte(ptep, ptev)
55#define arch_kmap_local_post_map(vaddr, pteval)	local_flush_tlb_one(vaddr)
56#define arch_kmap_local_post_unmap(vaddr)	local_flush_tlb_one(vaddr)
57
58#endif /* __KERNEL__ */
59
60#endif /* _ASM_HIGHMEM_H */