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 */ 30 extern unsigned long highstart_pfn, highend_pfn; 31 32 #define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE) 33 extern 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 */ 62
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.