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/module.h>
  14 #include <linux/sched.h>
  15 #include <linux/syscalls.h>
  16 #include <linux/mm.h>
  17
  18 #include <asm/cacheflush.h>
  19 #include <asm/processor.h>
  20 #include <asm/cpu.h>
  21 #include <asm/cpu-features.h>
  22
  23 /* Cache operations. */
  24 void (*flush_cache_all)(void);
  25 void (*__flush_cache_all)(void);
  26 void (*flush_cache_mm)(struct mm_struct *mm);
  27 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  28         unsigned long end);
  29 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  30         unsigned long pfn);
  31 void (*flush_icache_range)(unsigned long start, unsigned long end);
  32 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  33
  34 void (*__flush_cache_vmap)(void);
  35 void (*__flush_cache_vunmap)(void);
  36
  37 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
  38 void (*__invalidate_kernel_vmap_range)(unsigned long vaddr, int size);
  39
  40 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
  41
  42 /* MIPS specific cache operations */
  43 void (*flush_cache_sigtramp)(unsigned long addr);
  44 void (*local_flush_data_cache_page)(void * addr);
  45 void (*flush_data_cache_page)(unsigned long addr);
  46 void (*flush_icache_all)(void);
  47
  48 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
  49 EXPORT_SYMBOL(flush_data_cache_page);
  50 EXPORT_SYMBOL(flush_icache_all);
  51
  52 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
  53
  54 /* DMA cache operations. */
  55 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  56 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  57 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  58
  59 EXPORT_SYMBOL(_dma_cache_wback_inv);
  60
  61 #endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
  62
  63 /*
  64  * We could optimize the case where the cache argument is not BCACHE but
  65  * that seems very atypical use ...
  66  */
  67 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  68         unsigned int, cache)
  69 {
  70         if (bytes == 0)
  71                 return 0;
  72         if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
  73                 return -EFAULT;
  74
  75         flush_icache_range(addr, addr + bytes);
  76
  77         return 0;
  78 }
  79
  80 void __flush_dcache_page(struct page *page)
  81 {
  82         struct address_space *mapping = page_mapping(page);
  83         unsigned long addr;
  84
  85         if (PageHighMem(page))
  86                 return;
  87         if (mapping && !mapping_mapped(mapping)) {
  88                 SetPageDcacheDirty(page);
  89                 return;
  90         }
  91
  92         /*
  93          * We could delay the flush for the !page_mapping case too.  But that
  94          * case is for exec env/arg pages and those are %99 certainly going to
  95          * get faulted into the tlb (and thus flushed) anyways.
  96          */
  97         addr = (unsigned long) page_address(page);
  98         flush_data_cache_page(addr);
  99 }
 100
 101 EXPORT_SYMBOL(__flush_dcache_page);
 102
 103 void __flush_anon_page(struct page *page, unsigned long vmaddr)
 104 {
 105         unsigned long addr = (unsigned long) page_address(page);
 106
 107         if (pages_do_alias(addr, vmaddr)) {
 108                 if (page_mapped(page) && !Page_dcache_dirty(page)) {
 109                         void *kaddr;
 110
 111                         kaddr = kmap_coherent(page, vmaddr);
 112                         flush_data_cache_page((unsigned long)kaddr);
 113                         kunmap_coherent();
 114                 } else
 115                         flush_data_cache_page(addr);
 116         }
 117 }
 118
 119 EXPORT_SYMBOL(__flush_anon_page);
 120
 121 void __update_cache(struct vm_area_struct *vma, unsigned long address,
 122         pte_t pte)
 123 {
 124         struct page *page;
 125         unsigned long pfn, addr;
 126         int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
 127
 128         pfn = pte_pfn(pte);
 129         if (unlikely(!pfn_valid(pfn)))
 130                 return;
 131         page = pfn_to_page(pfn);
 132         if (page_mapping(page) && Page_dcache_dirty(page)) {
 133                 addr = (unsigned long) page_address(page);
 134                 if (exec || pages_do_alias(addr, address & PAGE_MASK))
 135                         flush_data_cache_page(addr);
 136                 ClearPageDcacheDirty(page);
 137         }
 138 }
 139
 140 unsigned long _page_cachable_default;
 141 EXPORT_SYMBOL(_page_cachable_default);
 142
 143 static inline void setup_protection_map(void)
 144 {
 145         if (cpu_has_rixi) {
 146                 protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 147                 protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 148                 protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 149                 protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 150                 protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
 151                 protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 152                 protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
 153                 protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 154
 155                 protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 156                 protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 157                 protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
 158                 protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
 159                 protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
 160                 protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 161                 protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE  | _PAGE_NO_READ);
 162                 protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
 163
 164         } else {
 165                 protection_map[0] = PAGE_NONE;
 166                 protection_map[1] = PAGE_READONLY;
 167                 protection_map[2] = PAGE_COPY;
 168                 protection_map[3] = PAGE_COPY;
 169                 protection_map[4] = PAGE_READONLY;
 170                 protection_map[5] = PAGE_READONLY;
 171                 protection_map[6] = PAGE_COPY;
 172                 protection_map[7] = PAGE_COPY;
 173                 protection_map[8] = PAGE_NONE;
 174                 protection_map[9] = PAGE_READONLY;
 175                 protection_map[10] = PAGE_SHARED;
 176                 protection_map[11] = PAGE_SHARED;
 177                 protection_map[12] = PAGE_READONLY;
 178                 protection_map[13] = PAGE_READONLY;
 179                 protection_map[14] = PAGE_SHARED;
 180                 protection_map[15] = PAGE_SHARED;
 181         }
 182 }
 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_6k_cache) {
 192                 extern void __weak r6k_cache_init(void);
 193
 194                 r6k_cache_init();
 195         }
 196         if (cpu_has_4k_cache) {
 197                 extern void __weak r4k_cache_init(void);
 198
 199                 r4k_cache_init();
 200         }
 201         if (cpu_has_8k_cache) {
 202                 extern void __weak r8k_cache_init(void);
 203
 204                 r8k_cache_init();
 205         }
 206         if (cpu_has_tx39_cache) {
 207                 extern void __weak tx39_cache_init(void);
 208
 209                 tx39_cache_init();
 210         }
 211
 212         if (cpu_has_octeon_cache) {
 213                 extern void __weak octeon_cache_init(void);
 214
 215                 octeon_cache_init();
 216         }
 217
 218         setup_protection_map();
 219 }
 220
 221 int __weak __uncached_access(struct file *file, unsigned long addr)
 222 {
 223         if (file->f_flags & O_DSYNC)
 224                 return 1;
 225
 226         return addr >= __pa(high_memory);
 227 }