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Diffstat (limited to 'arch/mips/include/asm/highmem.h')
-rw-r--r-- | arch/mips/include/asm/highmem.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h new file mode 100644 index 000000000..9f021cf51 --- /dev/null +++ b/arch/mips/include/asm/highmem.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * 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/bug.h> +#include <linux/interrupt.h> +#include <linux/uaccess.h> +#include <asm/cpu-features.h> +#include <asm/kmap_types.h> + +/* declarations for highmem.c */ +extern unsigned long highstart_pfn, highend_pfn; + +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. + */ +#if defined(CONFIG_PHYS_ADDR_T_64BIT) || defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) +#define LAST_PKMAP 512 +#else +#define LAST_PKMAP 1024 +#endif + +#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 ARCH_HAS_KMAP_FLUSH_TLB +extern void kmap_flush_tlb(unsigned long addr); +extern void *kmap_atomic_pfn(unsigned long pfn); + +#define flush_cache_kmaps() BUG_ON(cpu_has_dc_aliases) + +extern void kmap_init(void); + +#endif /* __KERNEL__ */ + +#endif /* _ASM_HIGHMEM_H */ |