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