Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * highmem.h: virtual kernel memory mappings for high memory |
| 3 | * |
| 4 | * Used in CONFIG_HIGHMEM systems for memory pages which |
| 5 | * are not addressable by direct kernel virtual addresses. |
| 6 | * |
| 7 | * Copyright (C) 1999 Gerhard Wichert, Siemens AG |
| 8 | * Gerhard.Wichert@pdb.siemens.de |
| 9 | * |
| 10 | * |
| 11 | * Redesigned the x86 32-bit VM architecture to deal with |
| 12 | * up to 16 Terabyte physical memory. With current x86 CPUs |
| 13 | * we now support up to 64 Gigabytes physical RAM. |
| 14 | * |
| 15 | * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> |
| 16 | */ |
| 17 | |
| 18 | #ifndef _ASM_HIGHMEM_H |
| 19 | #define _ASM_HIGHMEM_H |
| 20 | |
| 21 | #ifdef __KERNEL__ |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/interrupt.h> |
| 24 | #include <linux/threads.h> |
| 25 | #include <asm/kmap_types.h> |
| 26 | #include <asm/tlbflush.h> |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 27 | #include <asm/paravirt.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | |
| 29 | /* declarations for highmem.c */ |
| 30 | extern unsigned long highstart_pfn, highend_pfn; |
| 31 | |
| 32 | extern pte_t *kmap_pte; |
| 33 | extern pgprot_t kmap_prot; |
| 34 | extern pte_t *pkmap_page_table; |
| 35 | |
| 36 | /* |
| 37 | * Right now we initialize only a single pte table. It can be extended |
| 38 | * easily, subsequent pte tables have to be allocated in one physical |
| 39 | * chunk of RAM. |
| 40 | */ |
| 41 | #ifdef CONFIG_X86_PAE |
| 42 | #define LAST_PKMAP 512 |
| 43 | #else |
| 44 | #define LAST_PKMAP 1024 |
| 45 | #endif |
| 46 | /* |
| 47 | * Ordering is: |
| 48 | * |
| 49 | * FIXADDR_TOP |
| 50 | * fixed_addresses |
| 51 | * FIXADDR_START |
| 52 | * temp fixed addresses |
| 53 | * FIXADDR_BOOT_START |
| 54 | * Persistent kmap area |
| 55 | * PKMAP_BASE |
| 56 | * VMALLOC_END |
| 57 | * Vmalloc area |
| 58 | * VMALLOC_START |
| 59 | * high_memory |
| 60 | */ |
| 61 | #define PKMAP_BASE ( (FIXADDR_BOOT_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK ) |
| 62 | #define LAST_PKMAP_MASK (LAST_PKMAP-1) |
| 63 | #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) |
| 64 | #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) |
| 65 | |
Harvey Harrison | 599db4f | 2008-02-04 16:48:03 +0100 | [diff] [blame] | 66 | extern void *kmap_high(struct page *page); |
| 67 | extern void kunmap_high(struct page *page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
| 69 | void *kmap(struct page *page); |
| 70 | void kunmap(struct page *page); |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 71 | void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | void *kmap_atomic(struct page *page, enum km_type type); |
| 73 | void kunmap_atomic(void *kvaddr, enum km_type type); |
Vivek Goyal | 60e64d4 | 2005-06-25 14:58:19 -0700 | [diff] [blame] | 74 | void *kmap_atomic_pfn(unsigned long pfn, enum km_type type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | struct page *kmap_atomic_to_page(void *ptr); |
| 76 | |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 77 | #ifndef CONFIG_PARAVIRT |
| 78 | #define kmap_atomic_pte(page, type) kmap_atomic(page, type) |
| 79 | #endif |
| 80 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | #define flush_cache_kmaps() do { } while (0) |
| 82 | |
| 83 | #endif /* __KERNEL__ */ |
| 84 | |
| 85 | #endif /* _ASM_HIGHMEM_H */ |