arch/avr32/mm/cache.c

   1 /*
   2  * Copyright (C) 2004-2006 Atmel Corporation
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/highmem.h>
  10 #include <linux/unistd.h>
  11
  12 #include <asm/cacheflush.h>
  13 #include <asm/cachectl.h>
  14 #include <asm/processor.h>
  15 #include <asm/uaccess.h>
  16 #include <asm/syscalls.h>
  17
  18 /*
  19  * If you attempt to flush anything more than this, you need superuser
  20  * privileges.  The value is completely arbitrary.
  21  */
  22 #define CACHEFLUSH_MAX_LEN      1024
  23
  24 void invalidate_dcache_region(void *start, size_t size)
  25 {
  26         unsigned long v, begin, end, linesz, mask;
  27
  28         linesz = boot_cpu_data.dcache.linesz;
  29         mask = linesz - 1;
  30
  31         /* when first and/or last cachelines are shared, flush them
  32          * instead of invalidating ... never discard valid data!
  33          */
  34         begin = (unsigned long)start;
  35         end = begin + size;
  36
  37         if (begin & mask) {
  38                 flush_dcache_line(start);
  39                 begin += linesz;
  40         }
  41         if (end & mask) {
  42                 flush_dcache_line((void *)end);
  43                 end &= ~mask;
  44         }
  45
  46         /* remaining cachelines only need invalidation */
  47         for (v = begin; v < end; v += linesz)
  48                 invalidate_dcache_line((void *)v);
  49         flush_write_buffer();
  50 }
  51
  52 void clean_dcache_region(void *start, size_t size)
  53 {
  54         unsigned long v, begin, end, linesz;
  55
  56         linesz = boot_cpu_data.dcache.linesz;
  57         begin = (unsigned long)start & ~(linesz - 1);
  58         end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
  59
  60         for (v = begin; v < end; v += linesz)
  61                 clean_dcache_line((void *)v);
  62         flush_write_buffer();
  63 }
  64
  65 void flush_dcache_region(void *start, size_t size)
  66 {
  67         unsigned long v, begin, end, linesz;
  68
  69         linesz = boot_cpu_data.dcache.linesz;
  70         begin = (unsigned long)start & ~(linesz - 1);
  71         end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
  72
  73         for (v = begin; v < end; v += linesz)
  74                 flush_dcache_line((void *)v);
  75         flush_write_buffer();
  76 }
  77
  78 void invalidate_icache_region(void *start, size_t size)
  79 {
  80         unsigned long v, begin, end, linesz;
  81
  82         linesz = boot_cpu_data.icache.linesz;
  83         begin = (unsigned long)start & ~(linesz - 1);
  84         end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
  85
  86         for (v = begin; v < end; v += linesz)
  87                 invalidate_icache_line((void *)v);
  88 }
  89
  90 static inline void __flush_icache_range(unsigned long start, unsigned long end)
  91 {
  92         unsigned long v, linesz;
  93
  94         linesz = boot_cpu_data.dcache.linesz;
  95         for (v = start; v < end; v += linesz) {
  96                 clean_dcache_line((void *)v);
  97                 invalidate_icache_line((void *)v);
  98         }
  99
 100         flush_write_buffer();
 101 }
 102
 103 /*
 104  * This one is called after a module has been loaded.
 105  */
 106 void flush_icache_range(unsigned long start, unsigned long end)
 107 {
 108         unsigned long linesz;
 109
 110         linesz = boot_cpu_data.dcache.linesz;
 111         __flush_icache_range(start & ~(linesz - 1),
 112                              (end + linesz - 1) & ~(linesz - 1));
 113 }
 114
 115 /*
 116  * This one is called from __do_fault() and do_swap_page().
 117  */
 118 void flush_icache_page(struct vm_area_struct *vma, struct page *page)
 119 {
 120         if (vma->vm_flags & VM_EXEC) {
 121                 void *v = page_address(page);
 122                 __flush_icache_range((unsigned long)v, (unsigned long)v + PAGE_SIZE);
 123         }
 124 }
 125
 126 asmlinkage int sys_cacheflush(int operation, void __user *addr, size_t len)
 127 {
 128         int ret;
 129
 130         if (len > CACHEFLUSH_MAX_LEN) {
 131                 ret = -EPERM;
 132                 if (!capable(CAP_SYS_ADMIN))
 133                         goto out;
 134         }
 135
 136         ret = -EFAULT;
 137         if (!access_ok(VERIFY_WRITE, addr, len))
 138                 goto out;
 139
 140         switch (operation) {
 141         case CACHE_IFLUSH:
 142                 flush_icache_range((unsigned long)addr,
 143                                    (unsigned long)addr + len);
 144                 ret = 0;
 145                 break;
 146         default:
 147                 ret = -EINVAL;
 148         }
 149
 150 out:
 151         return ret;
 152 }
 153
 154 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
 155                 unsigned long vaddr, void *dst, const void *src,
 156                 unsigned long len)
 157 {
 158         memcpy(dst, src, len);
 159         if (vma->vm_flags & VM_EXEC)
 160                 flush_icache_range((unsigned long)dst,
 161                                 (unsigned long)dst + len);
 162 }