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 (ralf@linux-mips.org)
   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
  19 #include <asm/cacheflush.h>
  20 #include <asm/processor.h>
  21 #include <asm/cpu.h>
  22 #include <asm/cpu-features.h>
  23 #include <asm/setup.h>
  24
  25 /* Cache operations. */
  26 void (*flush_cache_all)(void);
  27 void (*__flush_cache_all)(void);
  28 EXPORT_SYMBOL_GPL(__flush_cache_all);
  29 void (*flush_cache_mm)(struct mm_struct *mm);
  30 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  31         unsigned long end);
  32 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  33         unsigned long pfn);
  34 void (*flush_icache_range)(unsigned long start, unsigned long end);
  35 EXPORT_SYMBOL_GPL(flush_icache_range);
  36 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  37 EXPORT_SYMBOL_GPL(local_flush_icache_range);
  38 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
  39 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
  40 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
  41
  42 void (*__flush_cache_vmap)(void);
  43 void (*__flush_cache_vunmap)(void);
  44
  45 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
  46 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
  47
  48 /* MIPS specific cache operations */
  49 void (*local_flush_data_cache_page)(void * addr);
  50 void (*flush_data_cache_page)(unsigned long addr);
  51 void (*flush_icache_all)(void);
  52
  53 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
  54 EXPORT_SYMBOL(flush_data_cache_page);
  55 EXPORT_SYMBOL(flush_icache_all);
  56
  57 #ifdef CONFIG_DMA_NONCOHERENT
  58
  59 /* DMA cache operations. */
  60 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  61 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  62 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  63
  64 #endif /* CONFIG_DMA_NONCOHERENT */
  65
  66 /*
  67  * We could optimize the case where the cache argument is not BCACHE but
  68  * that seems very atypical use ...
  69  */
  70 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  71         unsigned int, cache)
  72 {
  73         if (bytes == 0)
  74                 return 0;
  75         if (!access_ok((void __user *) addr, bytes))
  76                 return -EFAULT;
  77
  78         __flush_icache_user_range(addr, addr + bytes);
  79
  80         return 0;
  81 }
  82
  83 void __flush_dcache_page(struct page *page)
  84 {
  85         struct address_space *mapping = page_mapping_file(page);
  86         unsigned long addr;
  87
  88         if (mapping && !mapping_mapped(mapping)) {
  89                 SetPageDcacheDirty(page);
  90                 return;
  91         }
  92
  93         /*
  94          * We could delay the flush for the !page_mapping case too.  But that
  95          * case is for exec env/arg pages and those are %99 certainly going to
  96          * get faulted into the tlb (and thus flushed) anyways.
  97          */
  98         if (PageHighMem(page))
  99                 addr = (unsigned long)kmap_atomic(page);
 100         else
 101                 addr = (unsigned long)page_address(page);
 102
 103         flush_data_cache_page(addr);
 104
 105         if (PageHighMem(page))
 106                 kunmap_atomic((void *)addr);
 107 }
 108
 109 EXPORT_SYMBOL(__flush_dcache_page);
 110
 111 void __flush_anon_page(struct page *page, unsigned long vmaddr)
 112 {
 113         unsigned long addr = (unsigned long) page_address(page);
 114
 115         if (pages_do_alias(addr, vmaddr)) {
 116                 if (page_mapcount(page) && !Page_dcache_dirty(page)) {
 117                         void *kaddr;
 118
 119                         kaddr = kmap_coherent(page, vmaddr);
 120                         flush_data_cache_page((unsigned long)kaddr);
 121                         kunmap_coherent();
 122                 } else
 123                         flush_data_cache_page(addr);
 124         }
 125 }
 126
 127 EXPORT_SYMBOL(__flush_anon_page);
 128
 129 void __update_cache(unsigned long address, pte_t pte)
 130 {
 131         struct page *page;
 132         unsigned long pfn, addr;
 133         int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
 134
 135         pfn = pte_pfn(pte);
 136         if (unlikely(!pfn_valid(pfn)))
 137                 return;
 138         page = pfn_to_page(pfn);
 139         if (Page_dcache_dirty(page)) {
 140                 if (PageHighMem(page))
 141                         addr = (unsigned long)kmap_atomic(page);
 142                 else
 143                         addr = (unsigned long)page_address(page);
 144
 145                 if (exec || pages_do_alias(addr, address & PAGE_MASK))
 146                         flush_data_cache_page(addr);
 147
 148                 if (PageHighMem(page))
 149                         kunmap_atomic((void *)addr);
 150
 151                 ClearPageDcacheDirty(page);
 152         }
 153 }
 154
 155 unsigned long _page_cachable_default;
 156 EXPORT_SYMBOL(_page_cachable_default);
 157
 158 #define PM(p)   __pgprot(_page_cachable_default | (p))
 159
 160 static inline void setup_protection_map(void)
 161 {
 162         protection_map[0]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 163         protection_map[1]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 164         protection_map[2]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 165         protection_map[3]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 166         protection_map[4]  = PM(_PAGE_PRESENT);
 167         protection_map[5]  = PM(_PAGE_PRESENT);
 168         protection_map[6]  = PM(_PAGE_PRESENT);
 169         protection_map[7]  = PM(_PAGE_PRESENT);
 170
 171         protection_map[8]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 172         protection_map[9]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 173         protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
 174                                 _PAGE_NO_READ);
 175         protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
 176         protection_map[12] = PM(_PAGE_PRESENT);
 177         protection_map[13] = PM(_PAGE_PRESENT);
 178         protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 179         protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 180 }
 181
 182 #undef PM
 183
 184 void cpu_cache_init(void)
 185 {
 186         if (cpu_has_3k_cache) {
 187                 extern void __weak r3k_cache_init(void);
 188
 189                 r3k_cache_init();
 190         }
 191         if (cpu_has_4k_cache) {
 192                 extern void __weak r4k_cache_init(void);
 193
 194                 r4k_cache_init();
 195         }
 196         if (cpu_has_tx39_cache) {
 197                 extern void __weak tx39_cache_init(void);
 198
 199                 tx39_cache_init();
 200         }
 201
 202         if (cpu_has_octeon_cache) {
 203                 extern void __weak octeon_cache_init(void);
 204
 205                 octeon_cache_init();
 206         }
 207
 208         setup_protection_map();
 209 }
 210
 211 int __weak __uncached_access(struct file *file, unsigned long addr)
 212 {
 213         if (file->f_flags & O_DSYNC)
 214                 return 1;
 215
 216         return addr >= __pa(high_memory);
 217 }