arch/mips/mm/cache.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 - 2003, 06, 07 by Ralf Baechle ([email protected])
   7  * Copyright (C) 2007 MIPS Technologies, Inc.
   8  */
   9 #include <linux/fs.h>
  10 #include <linux/fcntl.h>
  11 #include <linux/kernel.h>
  12 #include <linux/linkage.h>
  13 #include <linux/export.h>
  14 #include <linux/sched.h>
  15 #include <linux/syscalls.h>
  16 #include <linux/mm.h>
  17 #include <linux/highmem.h>
  18 #include <linux/pagemap.h>
  19
  20 #include <asm/cacheflush.h>
  21 #include <asm/processor.h>
  22 #include <asm/cpu.h>
  23 #include <asm/cpu-features.h>
  24 #include <asm/setup.h>
  25 #include <asm/pgtable.h>
  26
  27 /* Cache operations. */
  28 void (*flush_cache_all)(void);
  29 void (*__flush_cache_all)(void);
  30 EXPORT_SYMBOL_GPL(__flush_cache_all);
  31 void (*flush_cache_mm)(struct mm_struct *mm);
  32 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  33         unsigned long end);
  34 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  35         unsigned long pfn);
  36 void (*flush_icache_range)(unsigned long start, unsigned long end);
  37 EXPORT_SYMBOL_GPL(flush_icache_range);
  38 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  39 EXPORT_SYMBOL_GPL(local_flush_icache_range);
  40 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
  41 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
  42 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
  43
  44 void (*__flush_cache_vmap)(void);
  45 void (*__flush_cache_vunmap)(void);
  46
  47 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
  48 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
  49
  50 /* MIPS specific cache operations */
  51 void (*local_flush_data_cache_page)(void * addr);
  52 void (*flush_data_cache_page)(unsigned long addr);
  53 void (*flush_icache_all)(void);
  54
  55 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
  56 EXPORT_SYMBOL(flush_data_cache_page);
  57 EXPORT_SYMBOL(flush_icache_all);
  58
  59 #ifdef CONFIG_DMA_NONCOHERENT
  60
  61 /* DMA cache operations. */
  62 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  63 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  64 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  65
  66 #endif /* CONFIG_DMA_NONCOHERENT */
  67
  68 /*
  69  * We could optimize the case where the cache argument is not BCACHE but
  70  * that seems very atypical use ...
  71  */
  72 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  73         unsigned int, cache)
  74 {
  75         if (bytes == 0)
  76                 return 0;
  77         if (!access_ok((void __user *) addr, bytes))
  78                 return -EFAULT;
  79
  80         __flush_icache_user_range(addr, addr + bytes);
  81
  82         return 0;
  83 }
  84
  85 void __flush_dcache_page(struct page *page)
  86 {
  87         struct address_space *mapping = page_mapping_file(page);
  88         unsigned long addr;
  89
  90         if (mapping && !mapping_mapped(mapping)) {
  91                 SetPageDcacheDirty(page);
  92                 return;
  93         }
  94
  95         /*
  96          * We could delay the flush for the !page_mapping case too.  But that
  97          * case is for exec env/arg pages and those are %99 certainly going to
  98          * get faulted into the tlb (and thus flushed) anyways.
  99          */
 100         if (PageHighMem(page))
 101                 addr = (unsigned long)kmap_atomic(page);
 102         else
 103                 addr = (unsigned long)page_address(page);
 104
 105         flush_data_cache_page(addr);
 106
 107         if (PageHighMem(page))
 108                 kunmap_atomic((void *)addr);
 109 }
 110
 111 EXPORT_SYMBOL(__flush_dcache_page);
 112
 113 void __flush_anon_page(struct page *page, unsigned long vmaddr)
 114 {
 115         unsigned long addr = (unsigned long) page_address(page);
 116
 117         if (pages_do_alias(addr, vmaddr)) {
 118                 if (page_mapcount(page) && !Page_dcache_dirty(page)) {
 119                         void *kaddr;
 120
 121                         kaddr = kmap_coherent(page, vmaddr);
 122                         flush_data_cache_page((unsigned long)kaddr);
 123                         kunmap_coherent();
 124                 } else
 125                         flush_data_cache_page(addr);
 126         }
 127 }
 128
 129 EXPORT_SYMBOL(__flush_anon_page);
 130
 131 void __update_cache(unsigned long address, pte_t pte)
 132 {
 133         struct page *page;
 134         unsigned long pfn, addr;
 135         int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
 136
 137         pfn = pte_pfn(pte);
 138         if (unlikely(!pfn_valid(pfn)))
 139                 return;
 140         page = pfn_to_page(pfn);
 141         if (Page_dcache_dirty(page)) {
 142                 if (PageHighMem(page))
 143                         addr = (unsigned long)kmap_atomic(page);
 144                 else
 145                         addr = (unsigned long)page_address(page);
 146
 147                 if (exec || pages_do_alias(addr, address & PAGE_MASK))
 148                         flush_data_cache_page(addr);
 149
 150                 if (PageHighMem(page))
 151                         kunmap_atomic((void *)addr);
 152
 153                 ClearPageDcacheDirty(page);
 154         }
 155 }
 156
 157 unsigned long _page_cachable_default;
 158 EXPORT_SYMBOL(_page_cachable_default);
 159
 160 #define PM(p)   __pgprot(_page_cachable_default | (p))
 161
 162 static inline void setup_protection_map(void)
 163 {
 164         protection_map[0]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 165         protection_map[1]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 166         protection_map[2]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 167         protection_map[3]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 168         protection_map[4]  = PM(_PAGE_PRESENT);
 169         protection_map[5]  = PM(_PAGE_PRESENT);
 170         protection_map[6]  = PM(_PAGE_PRESENT);
 171         protection_map[7]  = PM(_PAGE_PRESENT);
 172
 173         protection_map[8]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 174         protection_map[9]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 175         protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
 176                                 _PAGE_NO_READ);
 177         protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
 178         protection_map[12] = PM(_PAGE_PRESENT);
 179         protection_map[13] = PM(_PAGE_PRESENT);
 180         protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 181         protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 182 }
 183
 184 #undef PM
 185
 186 void cpu_cache_init(void)
 187 {
 188         if (cpu_has_3k_cache) {
 189                 extern void __weak r3k_cache_init(void);
 190
 191                 r3k_cache_init();
 192         }
 193         if (cpu_has_4k_cache) {
 194                 extern void __weak r4k_cache_init(void);
 195
 196                 r4k_cache_init();
 197         }
 198         if (cpu_has_tx39_cache) {
 199                 extern void __weak tx39_cache_init(void);
 200
 201                 tx39_cache_init();
 202         }
 203
 204         if (cpu_has_octeon_cache) {
 205                 extern void __weak octeon_cache_init(void);
 206
 207                 octeon_cache_init();
 208         }
 209
 210         setup_protection_map();
 211 }