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 Terrabyte 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
19#ifndef _ASM_HIGHMEM_H
20#define _ASM_HIGHMEM_H
21
22#ifdef __KERNEL__
23
24#include <linux/interrupt.h>
25#include <linux/pgtable.h>
26#include <asm/vaddrs.h>
27#include <asm/pgtsrmmu.h>
 
28
29/* declarations for highmem.c */
30extern unsigned long highstart_pfn, highend_pfn;
31
32#define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
33extern pte_t *pkmap_page_table;
34
 
 
35/*
36 * Right now we initialize only a single pte table. It can be extended
37 * easily, subsequent pte tables have to be allocated in one physical
38 * chunk of RAM.  Currently the simplest way to do this is to align the
39 * pkmap region on a pagetable boundary (4MB).
40 */
41#define LAST_PKMAP 1024
42#define PKMAP_SIZE (LAST_PKMAP << PAGE_SHIFT)
43#define PKMAP_BASE PMD_ALIGN(SRMMU_NOCACHE_VADDR + (SRMMU_MAX_NOCACHE_PAGES << PAGE_SHIFT))
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 PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
50
51#define flush_cache_kmaps()	flush_cache_all()
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
52
53/* FIXME: Use __flush_*_one(vaddr) instead of flush_*_all() -- Anton */
54#define arch_kmap_local_pre_map(vaddr, pteval)	flush_cache_all()
55#define arch_kmap_local_pre_unmap(vaddr)	flush_cache_all()
56#define arch_kmap_local_post_map(vaddr, pteval)	flush_tlb_all()
57#define arch_kmap_local_post_unmap(vaddr)	flush_tlb_all()
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 Terrabyte 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
19#ifndef _ASM_HIGHMEM_H
20#define _ASM_HIGHMEM_H
21
22#ifdef __KERNEL__
23
24#include <linux/interrupt.h>
 
25#include <asm/vaddrs.h>
26#include <asm/kmap_types.h>
27#include <asm/pgtable.h>
28
29/* declarations for highmem.c */
30extern unsigned long highstart_pfn, highend_pfn;
31
32extern pgprot_t kmap_prot;
33extern pte_t *pkmap_page_table;
34
35void kmap_init(void) __init;
36
37/*
38 * Right now we initialize only a single pte table. It can be extended
39 * easily, subsequent pte tables have to be allocated in one physical
40 * chunk of RAM.  Currently the simplest way to do this is to align the
41 * pkmap region on a pagetable boundary (4MB).
42 */
43#define LAST_PKMAP 1024
44#define PKMAP_SIZE (LAST_PKMAP << PAGE_SHIFT)
45#define PKMAP_BASE PMD_ALIGN(SRMMU_NOCACHE_VADDR + (SRMMU_MAX_NOCACHE_PAGES << PAGE_SHIFT))
46
47#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
48#define PKMAP_NR(virt)  ((virt - PKMAP_BASE) >> PAGE_SHIFT)
49#define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
50
51#define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
52
53void *kmap_high(struct page *page);
54void kunmap_high(struct page *page);
55
56static inline void *kmap(struct page *page)
57{
58	BUG_ON(in_interrupt());
59	if (!PageHighMem(page))
60		return page_address(page);
61	return kmap_high(page);
62}
63
64static inline void kunmap(struct page *page)
65{
66	BUG_ON(in_interrupt());
67	if (!PageHighMem(page))
68		return;
69	kunmap_high(page);
70}
71
72void *kmap_atomic(struct page *page);
73void __kunmap_atomic(void *kvaddr);
74
75#define flush_cache_kmaps()	flush_cache_all()
 
76
77#endif /* __KERNEL__ */
78
79#endif /* _ASM_HIGHMEM_H */