1 /* 2 * highmem.h: virtual kernel memory mappings for high memory 3 * 4 * Used in CONFIG_HIGHMEM systems for memory pages which 5 * are not addressable by direct kernel virtual addresses. 6 * 7 * Copyright (C) 1999 Gerhard Wichert, Siemens AG 8 * Gerhard.Wichert@pdb.siemens.de 9 * 10 * 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. 14 * 15 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> 16 */ 17 18 #ifndef _ASM_X86_HIGHMEM_H 19 #define _ASM_X86_HIGHMEM_H 20 21 #ifdef __KERNEL__ 22 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> 29 30 /* declarations for highmem.c */ 31 extern unsigned long highstart_pfn, highend_pfn; 32 33 /* 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 36 * chunk of RAM. 37 */ 38 /* 39 * Ordering is: 40 * 41 * FIXADDR_TOP 42 * fixed_addresses 43 * FIXADDR_START 44 * temp fixed addresses 45 * FIXADDR_BOOT_START 46 * Persistent kmap area 47 * PKMAP_BASE 48 * VMALLOC_END 49 * Vmalloc area 50 * VMALLOC_START 51 * high_memory 52 */ 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)) 56 57 extern void *kmap_high(struct page *page); 58 extern void kunmap_high(struct page *page); 59 60 void *kmap(struct page *page); 61 void kunmap(struct page *page); 62 63 void *kmap_atomic_prot(struct page *page, pgprot_t prot); 64 void *kmap_atomic(struct page *page); 65 void __kunmap_atomic(void *kvaddr); 66 void *kmap_atomic_pfn(unsigned long pfn); 67 void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot); 68 struct page *kmap_atomic_to_page(void *ptr); 69 70 #define flush_cache_kmaps() do { } while (0) 71 72 extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn, 73 unsigned long end_pfn); 74 75 #endif /* __KERNEL__ */ 76 77 #endif /* _ASM_X86_HIGHMEM_H */ 78