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Diffstat (limited to 'arch/metag/include/asm/highmem.h')
| -rw-r--r-- | arch/metag/include/asm/highmem.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/metag/include/asm/highmem.h b/arch/metag/include/asm/highmem.h new file mode 100644 index 00000000000..6646a15c73d --- /dev/null +++ b/arch/metag/include/asm/highmem.h @@ -0,0 +1,62 @@ +#ifndef _ASM_HIGHMEM_H +#define _ASM_HIGHMEM_H + +#include <asm/cacheflush.h> +#include <asm/kmap_types.h> +#include <asm/fixmap.h> + +/* + * 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 (from lower to higher memory addresses): + * + * high_memory + * Persistent kmap area + * PKMAP_BASE + * fixed_addresses + * FIXADDR_START + * FIXADDR_TOP + * Vmalloc area + * VMALLOC_START + * VMALLOC_END + */ +#define PKMAP_BASE (FIXADDR_START - PMD_SIZE) +#define LAST_PKMAP PTRS_PER_PTE +#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)) + +#define kmap_prot PAGE_KERNEL + +static inline void flush_cache_kmaps(void) +{ + flush_cache_all(); +} + +/* declarations for highmem.c */ +extern unsigned long highstart_pfn, highend_pfn; + +extern pte_t *pkmap_page_table; + +extern void *kmap_high(struct page *page); +extern void kunmap_high(struct page *page); + +extern void kmap_init(void); + +/* + * The following functions are already defined by <linux/highmem.h> + * when CONFIG_HIGHMEM is not set. + */ +#ifdef CONFIG_HIGHMEM +extern void *kmap(struct page *page); +extern void kunmap(struct page *page); +extern void *kmap_atomic(struct page *page); +extern void __kunmap_atomic(void *kvaddr); +extern void *kmap_atomic_pfn(unsigned long pfn); +extern struct page *kmap_atomic_to_page(void *ptr); +#endif + +#endif |