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Diffstat (limited to '')
| -rw-r--r-- | arch/x86/include/asm/highmem.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h new file mode 100644 index 000000000..0f420b24e --- /dev/null +++ b/arch/x86/include/asm/highmem.h @@ -0,0 +1,71 @@ +/* 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 Terabyte 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_X86_HIGHMEM_H +#define _ASM_X86_HIGHMEM_H + +#ifdef __KERNEL__ + +#include <linux/interrupt.h> +#include <linux/threads.h> +#include <asm/kmap_types.h> +#include <asm/tlbflush.h> +#include <asm/paravirt.h> +#include <asm/fixmap.h> + +/* declarations for highmem.c */ +extern unsigned long highstart_pfn, highend_pfn; + +/* + * 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. + */ +/* + * Ordering is: + * + * high memory on: high_memory off: + * FIXADDR_TOP FIXADDR_TOP + * fixed addresses fixed addresses + * FIXADDR_START FIXADDR_START + * temp fixed addresses/persistent kmap area VMALLOC_END + * PKMAP_BASE temp fixed addresses/vmalloc area + * VMALLOC_END VMALLOC_START + * vmalloc area high_memory + * VMALLOC_START + * high_memory + * + * The temp fixed area is only used during boot for early_ioremap(), and + * it is unused when the ioremap() is functional. vmalloc/pkmap area become + * available after early boot so the temp fixed area is available for re-use. + */ +#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)) + +void *kmap_atomic_pfn(unsigned long pfn); +void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot); + +#define flush_cache_kmaps() do { } while (0) + +extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn, + unsigned long end_pfn); + +#endif /* __KERNEL__ */ + +#endif /* _ASM_X86_HIGHMEM_H */ |