| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | /* |
| 3 | * highmem.h: virtual kernel memory mappings for high memory |
| 4 | * |
| 5 | * Used in CONFIG_HIGHMEM systems for memory pages which |
| 6 | * are not addressable by direct kernel virtual addresses. |
| 7 | * |
| 8 | * Copyright (C) 1999 Gerhard Wichert, Siemens AG |
| 9 | * Gerhard.Wichert@pdb.siemens.de |
| 10 | * |
| 11 | * |
| 12 | * Redesigned the x86 32-bit VM architecture to deal with |
| 13 | * up to 16 Terabyte physical memory. With current x86 CPUs |
| 14 | * we now support up to 64 Gigabytes physical RAM. |
| 15 | * |
| 16 | * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> |
| 17 | */ |
| 18 | |
| 19 | #ifndef _ASM_X86_HIGHMEM_H |
| 20 | #define _ASM_X86_HIGHMEM_H |
| 21 | |
| 22 | #ifdef __KERNEL__ |
| 23 | |
| 24 | #include <linux/interrupt.h> |
| 25 | #include <linux/threads.h> |
| 26 | #include <asm/kmap_types.h> |
| 27 | #include <asm/tlbflush.h> |
| 28 | #include <asm/paravirt.h> |
| 29 | #include <asm/fixmap.h> |
| 30 | |
| 31 | /* declarations for highmem.c */ |
| 32 | extern unsigned long highstart_pfn, highend_pfn; |
| 33 | |
| 34 | /* |
| 35 | * Right now we initialize only a single pte table. It can be extended |
| 36 | * easily, subsequent pte tables have to be allocated in one physical |
| 37 | * chunk of RAM. |
| 38 | */ |
| 39 | /* |
| 40 | * Ordering is: |
| 41 | * |
| 42 | * high memory on: high_memory off: |
| 43 | * FIXADDR_TOP FIXADDR_TOP |
| 44 | * fixed addresses fixed addresses |
| 45 | * FIXADDR_START FIXADDR_START |
| 46 | * temp fixed addresses/persistent kmap area VMALLOC_END |
| 47 | * PKMAP_BASE temp fixed addresses/vmalloc area |
| 48 | * VMALLOC_END VMALLOC_START |
| 49 | * vmalloc area high_memory |
| 50 | * VMALLOC_START |
| 51 | * high_memory |
| 52 | * |
| 53 | * The temp fixed area is only used during boot for early_ioremap(), and |
| 54 | * it is unused when the ioremap() is functional. vmalloc/pkmap area become |
| 55 | * available after early boot so the temp fixed area is available for re-use. |
| 56 | */ |
| 57 | #define LAST_PKMAP_MASK (LAST_PKMAP-1) |
| 58 | #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) |
| 59 | #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) |
| 60 | |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 61 | void *kmap_atomic_pfn(unsigned long pfn); |
| 62 | void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot); |
| 63 | |
| 64 | #define flush_cache_kmaps() do { } while (0) |
| 65 | |
| 66 | extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn, |
| 67 | unsigned long end_pfn); |
| 68 | |
| 69 | #endif /* __KERNEL__ */ |
| 70 | |
| 71 | #endif /* _ASM_X86_HIGHMEM_H */ |