2 * highmem.h: virtual kernel memory mappings for high memory
4 * Used in CONFIG_HIGHMEM systems for memory pages which
5 * are not addressable by direct kernel virtual addresses.
7 * Copyright (C) 1999 Gerhard Wichert, Siemens AG
8 * Gerhard.Wichert@pdb.siemens.de
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.
15 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
18 #ifndef _ASM_X86_HIGHMEM_H
19 #define _ASM_X86_HIGHMEM_H
23 #include <linux/interrupt.h>
24 #include <linux/threads.h>
25 #include <asm/kmap_types.h>
26 #include <asm/tlbflush.h>
27 #include <asm/paravirt.h>
28 #include <asm/fixmap.h>
30 /* declarations for highmem.c */
31 extern unsigned long highstart_pfn, highend_pfn;
34 * Right now we initialize only a single pte table. It can be extended
35 * easily, subsequent pte tables have to be allocated in one physical
44 * temp fixed addresses
46 * Persistent kmap area
53 #define LAST_PKMAP_MASK (LAST_PKMAP-1)
54 #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
55 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
57 extern void *kmap_high(struct page *page);
58 extern void kunmap_high(struct page *page);
60 void *kmap(struct page *page);
61 void kunmap(struct page *page);
62 void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot);
63 void *kmap_atomic(struct page *page, enum km_type type);
64 void kunmap_atomic(void *kvaddr, enum km_type type);
65 void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
66 void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot);
67 struct page *kmap_atomic_to_page(void *ptr);
69 #define flush_cache_kmaps() do { } while (0)
71 extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn,
72 unsigned long end_pfn);
74 #endif /* __KERNEL__ */
76 #endif /* _ASM_X86_HIGHMEM_H */