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/* SPDX-License-Identifier: GPL-2.0 */
/*
* 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 <linux/pgtable.h>
#include <asm/vaddrs.h>
#include <asm/pgtsrmmu.h>
/* declarations for highmem.c */
extern unsigned long highstart_pfn, highend_pfn;
#define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
extern pte_t *pkmap_page_table;
/*
* 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))
#define flush_cache_kmaps() flush_cache_all()
/* FIXME: Use __flush_*_one(vaddr) instead of flush_*_all() -- Anton */
#define arch_kmap_local_pre_map(vaddr, pteval) flush_cache_all()
#define arch_kmap_local_pre_unmap(vaddr) flush_cache_all()
#define arch_kmap_local_post_map(vaddr, pteval) flush_tlb_all()
#define arch_kmap_local_post_unmap(vaddr) flush_tlb_all()
#endif /* __KERNEL__ */
#endif /* _ASM_HIGHMEM_H */
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