1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 | /* MN10300 Virtual kernel memory mappings for high memory * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * - Derived from include/asm-i386/highmem.h * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public Licence * as published by the Free Software Foundation; either version * 2 of the Licence, or (at your option) any later version. */ #ifndef _ASM_HIGHMEM_H #define _ASM_HIGHMEM_H #ifdef __KERNEL__ #include <linux/init.h> #include <linux/interrupt.h> #include <linux/highmem.h> #include <asm/kmap_types.h> #include <asm/pgtable.h> /* undef for production */ #undef HIGHMEM_DEBUG /* declarations for highmem.c */ extern unsigned long highstart_pfn, highend_pfn; extern pte_t *kmap_pte; extern pgprot_t kmap_prot; extern pte_t *pkmap_page_table; extern void __init kmap_init(void); /* * 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. */ #define PKMAP_BASE 0xfe000000UL #define LAST_PKMAP 1024 #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)) extern unsigned long kmap_high(struct page *page); extern void kunmap_high(struct page *page); static inline unsigned long kmap(struct page *page) { if (in_interrupt()) BUG(); if (page < highmem_start_page) return page_address(page); return kmap_high(page); } static inline void kunmap(struct page *page) { if (in_interrupt()) BUG(); if (page < highmem_start_page) return; kunmap_high(page); } /* * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap * gives a more generic (and caching) interface. But kmap_atomic can * be used in IRQ contexts, so in some (very limited) cases we need * it. */ static inline void *kmap_atomic(struct page *page) { unsigned long vaddr; int idx, type; preempt_disable(); pagefault_disable(); if (page < highmem_start_page) return page_address(page); type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); #if HIGHMEM_DEBUG if (!pte_none(*(kmap_pte - idx))) BUG(); #endif set_pte(kmap_pte - idx, mk_pte(page, kmap_prot)); local_flush_tlb_one(vaddr); return (void *)vaddr; } static inline void __kunmap_atomic(unsigned long vaddr) { int type; if (vaddr < FIXADDR_START) { /* FIXME */ pagefault_enable(); preempt_enable(); return; } type = kmap_atomic_idx(); #if HIGHMEM_DEBUG { unsigned int idx; idx = type + KM_TYPE_NR * smp_processor_id(); if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx)) BUG(); /* * force other mappings to Oops if they'll try to access * this pte without first remap it */ pte_clear(kmap_pte - idx); local_flush_tlb_one(vaddr); } #endif kmap_atomic_idx_pop(); pagefault_enable(); preempt_enable(); } #endif /* __KERNEL__ */ #endif /* _ASM_HIGHMEM_H */ |