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/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/linkage.h>
  14 #include <linux/module.h>
  15 #include <linux/sched.h>
  16 #include <linux/syscalls.h>
  17 #include <linux/mm.h>
  18
  19 #include <asm/cacheflush.h>
  20 #include <asm/processor.h>
  21 #include <asm/cpu.h>
  22 #include <asm/cpu-features.h>
  23
  24 /* Cache operations. */
  25 void (*flush_cache_all)(void);
  26 void (*__flush_cache_all)(void);
  27 void (*flush_cache_mm)(struct mm_struct *mm);
  28 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  29         unsigned long end);
  30 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  31         unsigned long pfn);
  32 void (*flush_icache_range)(unsigned long start, unsigned long end);
  33 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  34
  35 void (*__flush_cache_vmap)(void);
  36 void (*__flush_cache_vunmap)(void);
  37
  38 /* MIPS specific cache operations */
  39 void (*flush_cache_sigtramp)(unsigned long addr);
  40 void (*local_flush_data_cache_page)(void * addr);
  41 void (*flush_data_cache_page)(unsigned long addr);
  42 void (*flush_icache_all)(void);
  43
  44 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
  45 EXPORT_SYMBOL(flush_data_cache_page);
  46
  47 #ifdef CONFIG_DMA_NONCOHERENT
  48
  49 /* DMA cache operations. */
  50 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  51 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  52 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  53
  54 EXPORT_SYMBOL(_dma_cache_wback_inv);
  55
  56 #endif /* CONFIG_DMA_NONCOHERENT */
  57
  58 /*
  59  * We could optimize the case where the cache argument is not BCACHE but
  60  * that seems very atypical use ...
  61  */
  62 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  63         unsigned int, cache)
  64 {
  65         if (bytes == 0)
  66                 return 0;
  67         if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
  68                 return -EFAULT;
  69
  70         flush_icache_range(addr, addr + bytes);
  71
  72         return 0;
  73 }
  74
  75 void __flush_dcache_page(struct page *page)
  76 {
  77         struct address_space *mapping = page_mapping(page);
  78         unsigned long addr;
  79
  80         if (PageHighMem(page))
  81                 return;
  82         if (mapping && !mapping_mapped(mapping)) {
  83                 SetPageDcacheDirty(page);
  84                 return;
  85         }
  86
  87         /*
  88          * We could delay the flush for the !page_mapping case too.  But that
  89          * case is for exec env/arg pages and those are %99 certainly going to
  90          * get faulted into the tlb (and thus flushed) anyways.
  91          */
  92         addr = (unsigned long) page_address(page);
  93         flush_data_cache_page(addr);
  94 }
  95
  96 EXPORT_SYMBOL(__flush_dcache_page);
  97
  98 void __flush_anon_page(struct page *page, unsigned long vmaddr)
  99 {
 100         unsigned long addr = (unsigned long) page_address(page);
 101
 102         if (pages_do_alias(addr, vmaddr)) {
 103                 if (page_mapped(page) && !Page_dcache_dirty(page)) {
 104                         void *kaddr;
 105
 106                         kaddr = kmap_coherent(page, vmaddr);
 107                         flush_data_cache_page((unsigned long)kaddr);
 108                         kunmap_coherent();
 109                 } else
 110                         flush_data_cache_page(addr);
 111         }
 112 }
 113
 114 EXPORT_SYMBOL(__flush_anon_page);
 115
 116 void __update_cache(struct vm_area_struct *vma, unsigned long address,
 117         pte_t pte)
 118 {
 119         struct page *page;
 120         unsigned long pfn, addr;
 121         int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
 122
 123         pfn = pte_pfn(pte);
 124         if (unlikely(!pfn_valid(pfn)))
 125                 return;
 126         page = pfn_to_page(pfn);
 127         if (page_mapping(page) && Page_dcache_dirty(page)) {
 128                 addr = (unsigned long) page_address(page);
 129                 if (exec || pages_do_alias(addr, address & PAGE_MASK))
 130                         flush_data_cache_page(addr);
 131                 ClearPageDcacheDirty(page);
 132         }
 133 }
 134
 135 unsigned long _page_cachable_default;
 136 EXPORT_SYMBOL_GPL(_page_cachable_default);
 137
 138 static inline void setup_protection_map(void)
 139 {
 140         protection_map[0] = PAGE_NONE;
 141         protection_map[1] = PAGE_READONLY;
 142         protection_map[2] = PAGE_COPY;
 143         protection_map[3] = PAGE_COPY;
 144         protection_map[4] = PAGE_READONLY;
 145         protection_map[5] = PAGE_READONLY;
 146         protection_map[6] = PAGE_COPY;
 147         protection_map[7] = PAGE_COPY;
 148         protection_map[8] = PAGE_NONE;
 149         protection_map[9] = PAGE_READONLY;
 150         protection_map[10] = PAGE_SHARED;
 151         protection_map[11] = PAGE_SHARED;
 152         protection_map[12] = PAGE_READONLY;
 153         protection_map[13] = PAGE_READONLY;
 154         protection_map[14] = PAGE_SHARED;
 155         protection_map[15] = PAGE_SHARED;
 156 }
 157
 158 void __devinit cpu_cache_init(void)
 159 {
 160         if (cpu_has_3k_cache) {
 161                 extern void __weak r3k_cache_init(void);
 162
 163                 r3k_cache_init();
 164         }
 165         if (cpu_has_6k_cache) {
 166                 extern void __weak r6k_cache_init(void);
 167
 168                 r6k_cache_init();
 169         }
 170         if (cpu_has_4k_cache) {
 171                 extern void __weak r4k_cache_init(void);
 172
 173                 r4k_cache_init();
 174         }
 175         if (cpu_has_8k_cache) {
 176                 extern void __weak r8k_cache_init(void);
 177
 178                 r8k_cache_init();
 179         }
 180         if (cpu_has_tx39_cache) {
 181                 extern void __weak tx39_cache_init(void);
 182
 183                 tx39_cache_init();
 184         }
 185
 186         if (cpu_has_octeon_cache) {
 187                 extern void __weak octeon_cache_init(void);
 188
 189                 octeon_cache_init();
 190         }
 191
 192         setup_protection_map();
 193 }
 194
 195 int __weak __uncached_access(struct file *file, unsigned long addr)
 196 {
 197         if (file->f_flags & O_SYNC)
 198                 return 1;
 199
 200         return addr >= __pa(high_memory);
 201 }