include/asm-parisc/cacheflush.h

   1 #ifndef _PARISC_CACHEFLUSH_H
   2 #define _PARISC_CACHEFLUSH_H
   3
   4 #include <linux/config.h>
   5 #include <linux/mm.h>
   6 #include <asm/cache.h>  /* for flush_user_dcache_range_asm() proto */
   7
   8 /* The usual comment is "Caches aren't brain-dead on the <architecture>".
   9  * Unfortunately, that doesn't apply to PA-RISC. */
  10
  11 /* Cache flush operations */
  12
  13 #ifdef CONFIG_SMP
  14 #define flush_cache_mm(mm) flush_cache_all()
  15 #else
  16 #define flush_cache_mm(mm) flush_cache_all_local()
  17 #endif
  18
  19 #define flush_kernel_dcache_range(start,size) \
  20         flush_kernel_dcache_range_asm((start), (start)+(size));
  21
  22 extern void flush_cache_all_local(void);
  23
  24 static inline void cacheflush_h_tmp_function(void *dummy)
  25 {
  26         flush_cache_all_local();
  27 }
  28
  29 static inline void flush_cache_all(void)
  30 {
  31         on_each_cpu(cacheflush_h_tmp_function, NULL, 1, 1);
  32 }
  33
  34 #define flush_cache_vmap(start, end)            flush_cache_all()
  35 #define flush_cache_vunmap(start, end)          flush_cache_all()
  36
  37 extern int parisc_cache_flush_threshold;
  38 void parisc_setup_cache_timing(void);
  39
  40 static inline void
  41 flush_user_dcache_range(unsigned long start, unsigned long end)
  42 {
  43         if ((end - start) < parisc_cache_flush_threshold)
  44                 flush_user_dcache_range_asm(start,end);
  45         else
  46                 flush_data_cache();
  47 }
  48
  49 static inline void
  50 flush_user_icache_range(unsigned long start, unsigned long end)
  51 {
  52         if ((end - start) < parisc_cache_flush_threshold)
  53                 flush_user_icache_range_asm(start,end);
  54         else
  55                 flush_instruction_cache();
  56 }
  57
  58 extern void flush_dcache_page(struct page *page);
  59
  60 #define flush_dcache_mmap_lock(mapping) \
  61         write_lock_irq(&(mapping)->tree_lock)
  62 #define flush_dcache_mmap_unlock(mapping) \
  63         write_unlock_irq(&(mapping)->tree_lock)
  64
  65 #define flush_icache_page(vma,page)     do { flush_kernel_dcache_page(page_address(page)); flush_kernel_icache_page(page_address(page)); } while (0)
  66
  67 #define flush_icache_range(s,e)         do { flush_kernel_dcache_range_asm(s,e); flush_kernel_icache_range_asm(s,e); } while (0)
  68
  69 #define copy_to_user_page(vma, page, vaddr, dst, src, len) \
  70 do { \
  71         flush_cache_page(vma, vaddr, page_to_pfn(page)); \
  72         memcpy(dst, src, len); \
  73         flush_kernel_dcache_range_asm((unsigned long)dst, (unsigned long)dst + len); \
  74 } while (0)
  75
  76 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
  77 do { \
  78         flush_cache_page(vma, vaddr, page_to_pfn(page)); \
  79         memcpy(dst, src, len); \
  80 } while (0)
  81
  82 static inline void flush_cache_range(struct vm_area_struct *vma,
  83                 unsigned long start, unsigned long end)
  84 {
  85         int sr3;
  86
  87         if (!vma->vm_mm->context) {
  88                 BUG();
  89                 return;
  90         }
  91
  92         sr3 = mfsp(3);
  93         if (vma->vm_mm->context == sr3) {
  94                 flush_user_dcache_range(start,end);
  95                 flush_user_icache_range(start,end);
  96         } else {
  97                 flush_cache_all();
  98         }
  99 }
 100
 101 /* Simple function to work out if we have an existing address translation
 102  * for a user space vma. */
 103 static inline int translation_exists(struct vm_area_struct *vma,
 104                                 unsigned long addr, unsigned long pfn)
 105 {
 106         pgd_t *pgd = pgd_offset(vma->vm_mm, addr);
 107         pmd_t *pmd;
 108         pte_t pte;
 109
 110         if(pgd_none(*pgd))
 111                 return 0;
 112
 113         pmd = pmd_offset(pgd, addr);
 114         if(pmd_none(*pmd) || pmd_bad(*pmd))
 115                 return 0;
 116
 117         /* We cannot take the pte lock here: flush_cache_page is usually
 118          * called with pte lock already held.  Whereas flush_dcache_page
 119          * takes flush_dcache_mmap_lock, which is lower in the hierarchy:
 120          * the vma itself is secure, but the pte might come or go racily.
 121          */
 122         pte = *pte_offset_map(pmd, addr);
 123         /* But pte_unmap() does nothing on this architecture */
 124
 125         /* Filter out coincidental file entries and swap entries */
 126         if (!(pte_val(pte) & (_PAGE_FLUSH|_PAGE_PRESENT)))
 127                 return 0;
 128
 129         return pte_pfn(pte) == pfn;
 130 }
 131
 132 /* Private function to flush a page from the cache of a non-current
 133  * process.  cr25 contains the Page Directory of the current user
 134  * process; we're going to hijack both it and the user space %sr3 to
 135  * temporarily make the non-current process current.  We have to do
 136  * this because cache flushing may cause a non-access tlb miss which
 137  * the handlers have to fill in from the pgd of the non-current
 138  * process. */
 139 static inline void
 140 flush_user_cache_page_non_current(struct vm_area_struct *vma,
 141                                   unsigned long vmaddr)
 142 {
 143         /* save the current process space and pgd */
 144         unsigned long space = mfsp(3), pgd = mfctl(25);
 145
 146         /* we don't mind taking interrups since they may not
 147          * do anything with user space, but we can't
 148          * be preempted here */
 149         preempt_disable();
 150
 151         /* make us current */
 152         mtctl(__pa(vma->vm_mm->pgd), 25);
 153         mtsp(vma->vm_mm->context, 3);
 154
 155         flush_user_dcache_page(vmaddr);
 156         if(vma->vm_flags & VM_EXEC)
 157                 flush_user_icache_page(vmaddr);
 158
 159         /* put the old current process back */
 160         mtsp(space, 3);
 161         mtctl(pgd, 25);
 162         preempt_enable();
 163 }
 164
 165 static inline void
 166 __flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr)
 167 {
 168         if (likely(vma->vm_mm->context == mfsp(3))) {
 169                 flush_user_dcache_page(vmaddr);
 170                 if (vma->vm_flags & VM_EXEC)
 171                         flush_user_icache_page(vmaddr);
 172         } else {
 173                 flush_user_cache_page_non_current(vma, vmaddr);
 174         }
 175 }
 176
 177 static inline void
 178 flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
 179 {
 180         BUG_ON(!vma->vm_mm->context);
 181
 182         if (likely(translation_exists(vma, vmaddr, pfn)))
 183                 __flush_cache_page(vma, vmaddr);
 184
 185 }
 186 #endif