| /* 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_X86_HIGHMEM_H |
| #define _ASM_X86_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> |
| #include <asm/fixmap.h> |
| |
| /* declarations for highmem.c */ |
| extern unsigned long highstart_pfn, highend_pfn; |
| |
| /* |
| * 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: |
| * |
| * high memory on: high_memory off: |
| * FIXADDR_TOP FIXADDR_TOP |
| * fixed addresses fixed addresses |
| * FIXADDR_START FIXADDR_START |
| * temp fixed addresses/persistent kmap area VMALLOC_END |
| * PKMAP_BASE temp fixed addresses/vmalloc area |
| * VMALLOC_END VMALLOC_START |
| * vmalloc area high_memory |
| * VMALLOC_START |
| * high_memory |
| * |
| * The temp fixed area is only used during boot for early_ioremap(), and |
| * it is unused when the ioremap() is functional. vmalloc/pkmap area become |
| * available after early boot so the temp fixed area is available for re-use. |
| */ |
| #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)) |
| |
| void *kmap_atomic_pfn(unsigned long pfn); |
| void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot); |
| |
| #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_X86_HIGHMEM_H */ |
