/* * 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_HIGHMEM_H #define _ASM_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> /* declarations for highmem.c */ extern unsigned long highstart_pfn, highend_pfn; extern pte_t *kmap_pte; extern pgprot_t kmap_prot; 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. */ /* * Ordering is: * * FIXADDR_TOP * fixed_addresses * FIXADDR_START * temp fixed addresses * FIXADDR_BOOT_START * Persistent kmap area * PKMAP_BASE * VMALLOC_END * Vmalloc area * VMALLOC_START * high_memory */ #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)) extern void *kmap_high(struct page *page); extern void kunmap_high(struct page *page); void *kmap(struct page *page); void kunmap(struct page *page); void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot); void *kmap_atomic(struct page *page, enum km_type type); void kunmap_atomic(void *kvaddr, enum km_type type); void *kmap_atomic_pfn(unsigned long pfn, enum km_type type); struct page *kmap_atomic_to_page(void *ptr); #ifndef CONFIG_PARAVIRT #define kmap_atomic_pte(page, type) kmap_atomic(page, type) #endif #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_HIGHMEM_H */