kernel/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/highmem.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 EXPORT_SYMBOL_GPL(flush_icache_range);
  34 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  35 EXPORT_SYMBOL_GPL(local_flush_icache_range);
  36
  37 void (*__flush_cache_vmap)(void);
  38 void (*__flush_cache_vunmap)(void);
  39
  40 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
  41 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
  42 void (*__invalidate_kernel_vmap_range)(unsigned long vaddr, int size);
  43
  44 /* MIPS specific cache operations */
  45 void (*flush_cache_sigtramp)(unsigned long addr);
  46 void (*local_flush_data_cache_page)(void * addr);
  47 void (*flush_data_cache_page)(unsigned long addr);
  48 void (*flush_icache_all)(void);
  49
  50 EXPORT_SYMBOL_GPL(local_flush_data_cache_page);
  51 EXPORT_SYMBOL(flush_data_cache_page);
  52 EXPORT_SYMBOL(flush_icache_all);
  53
  54 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
  55
  56 /* DMA cache operations. */
  57 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  58 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  59 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  60
  61 EXPORT_SYMBOL(_dma_cache_wback_inv);
  62
  63 #endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
  64
  65 /*
  66  * We could optimize the case where the cache argument is not BCACHE but
  67  * that seems very atypical use ...
  68  */
  69 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  70         unsigned int, cache)
  71 {
  72         if (bytes == 0)
  73                 return 0;
  74         if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
  75                 return -EFAULT;
  76
  77         flush_icache_range(addr, addr + bytes);
  78
  79         return 0;
  80 }
  81
  82 void __flush_dcache_page(struct page *page)
  83 {
  84         struct address_space *mapping = page_mapping(page);
  85         unsigned long addr;
  86
  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         if (PageHighMem(page))
  98                 addr = (unsigned long)kmap_atomic(page);
  99         else
 100                 addr = (unsigned long)page_address(page);
 101
 102         flush_data_cache_page(addr);
 103
 104         if (PageHighMem(page))
 105                 __kunmap_atomic((void *)addr);
 106 }
 107
 108 EXPORT_SYMBOL(__flush_dcache_page);
 109
 110 void __flush_anon_page(struct page *page, unsigned long vmaddr)
 111 {
 112         unsigned long addr = (unsigned long) page_address(page);
 113
 114         if (pages_do_alias(addr, vmaddr)) {
 115                 if (page_mapped(page) && !Page_dcache_dirty(page)) {
 116                         void *kaddr;
 117
 118                         kaddr = kmap_coherent(page, vmaddr);
 119                         flush_data_cache_page((unsigned long)kaddr);
 120                         kunmap_coherent();
 121                 } else
 122                         flush_data_cache_page(addr);
 123         }
 124 }
 125
 126 EXPORT_SYMBOL(__flush_anon_page);
 127
 128 void __update_cache(unsigned long address, pte_t pte)
 129 {
 130         struct page *page;
 131         unsigned long pfn, addr;
 132         int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
 133
 134         pfn = pte_pfn(pte);
 135         if (unlikely(!pfn_valid(pfn)))
 136                 return;
 137         page = pfn_to_page(pfn);
 138         if (Page_dcache_dirty(page)) {
 139                 if (PageHighMem(page))
 140                         addr = (unsigned long)kmap_atomic(page);
 141                 else
 142                         addr = (unsigned long)page_address(page);
 143
 144                 if (exec || pages_do_alias(addr, address & PAGE_MASK))
 145                         flush_data_cache_page(addr);
 146
 147                 if (PageHighMem(page))
 148                         __kunmap_atomic((void *)addr);
 149
 150                 ClearPageDcacheDirty(page);
 151         }
 152 }
 153
 154 unsigned long _page_cachable_default;
 155 EXPORT_SYMBOL(_page_cachable_default);
 156
 157 static inline void setup_protection_map(void)
 158 {
 159         if (cpu_has_rixi) {
 160                 protection_map[0]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 161                 protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 162                 protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 163                 protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 164                 protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 165                 protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 166                 protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 167                 protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 168
 169                 protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 170                 protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 171                 protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
 172                 protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
 173                 protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 174                 protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 175                 protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
 176                 protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
 177
 178         } else {
 179                 protection_map[0] = PAGE_NONE;
 180                 protection_map[1] = PAGE_READONLY;
 181                 protection_map[2] = PAGE_COPY;
 182                 protection_map[3] = PAGE_COPY;
 183                 protection_map[4] = PAGE_READONLY;
 184                 protection_map[5] = PAGE_READONLY;
 185                 protection_map[6] = PAGE_COPY;
 186                 protection_map[7] = PAGE_COPY;
 187                 protection_map[8] = PAGE_NONE;
 188                 protection_map[9] = PAGE_READONLY;
 189                 protection_map[10] = PAGE_SHARED;
 190                 protection_map[11] = PAGE_SHARED;
 191                 protection_map[12] = PAGE_READONLY;
 192                 protection_map[13] = PAGE_READONLY;
 193                 protection_map[14] = PAGE_SHARED;
 194                 protection_map[15] = PAGE_SHARED;
 195         }
 196 }
 197
 198 void cpu_cache_init(void)
 199 {
 200         if (cpu_has_3k_cache) {
 201                 extern void __weak r3k_cache_init(void);
 202
 203                 r3k_cache_init();
 204         }
 205         if (cpu_has_6k_cache) {
 206                 extern void __weak r6k_cache_init(void);
 207
 208                 r6k_cache_init();
 209         }
 210         if (cpu_has_4k_cache) {
 211                 extern void __weak r4k_cache_init(void);
 212
 213                 r4k_cache_init();
 214         }
 215         if (cpu_has_8k_cache) {
 216                 extern void __weak r8k_cache_init(void);
 217
 218                 r8k_cache_init();
 219         }
 220         if (cpu_has_tx39_cache) {
 221                 extern void __weak tx39_cache_init(void);
 222
 223                 tx39_cache_init();
 224         }
 225
 226         if (cpu_has_octeon_cache) {
 227                 extern void __weak octeon_cache_init(void);
 228
 229                 octeon_cache_init();
 230         }
 231
 232         setup_protection_map();
 233 }
 234
 235 int __weak __uncached_access(struct file *file, unsigned long addr)
 236 {
 237         if (file->f_flags & O_DSYNC)
 238                 return 1;
 239
 240         return addr >= __pa(high_memory);
 241 }