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Diffstat (limited to 'arch/mips/include/asm/highmem.h')
-rw-r--r-- | arch/mips/include/asm/highmem.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h new file mode 100644 index 00000000000..4374ab2adc7 --- /dev/null +++ b/arch/mips/include/asm/highmem.h @@ -0,0 +1,67 @@ +/* + * 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/init.h> +#include <linux/interrupt.h> +#include <linux/uaccess.h> +#include <asm/kmap_types.h> + +/* undef for production */ +#define HIGHMEM_DEBUG 1 + +/* 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. + */ +#define LAST_PKMAP 1024 +#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); + +extern void *__kmap(struct page *page); +extern void __kunmap(struct page *page); +extern void *__kmap_atomic(struct page *page, enum km_type type); +extern void __kunmap_atomic(void *kvaddr, enum km_type type); +extern void *kmap_atomic_pfn(unsigned long pfn, enum km_type type); +extern struct page *__kmap_atomic_to_page(void *ptr); + +#define kmap __kmap +#define kunmap __kunmap +#define kmap_atomic __kmap_atomic +#define kunmap_atomic __kunmap_atomic +#define kmap_atomic_to_page __kmap_atomic_to_page + +#define flush_cache_kmaps() flush_cache_all() + +#endif /* __KERNEL__ */ + +#endif /* _ASM_HIGHMEM_H */ |