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
  17 /*
  18  * If you attempt to flush anything more than this, you need superuser
  19  * privileges.  The value is completely arbitrary.
  20  */
  21 #define CACHEFLUSH_MAX_LEN      1024
  22
  23 void invalidate_dcache_region(void *start, size_t size)
  24 {
  25         unsigned long v, begin, end, linesz;
  26
  27         linesz = boot_cpu_data.dcache.linesz;
  28
  29         //printk("invalidate dcache: %p + %u\n", start, size);
  30
  31         /* You asked for it, you got it */
  32         begin = (unsigned long)start & ~(linesz - 1);
  33         end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
  34
  35         for (v = begin; v < end; v += linesz)
  36                 invalidate_dcache_line((void *)v);
  37 }
  38
  39 void clean_dcache_region(void *start, size_t size)
  40 {
  41         unsigned long v, begin, end, linesz;
  42
  43         linesz = boot_cpu_data.dcache.linesz;
  44         begin = (unsigned long)start & ~(linesz - 1);
  45         end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);
  46
  47         for (v = begin; v < end; v += linesz)
  48                 clean_dcache_line((void *)v);
  49         flush_write_buffer();
  50 }
  51
  52 void flush_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                 flush_dcache_line((void *)v);
  62         flush_write_buffer();
  63 }
  64
  65 void invalidate_icache_region(void *start, size_t size)
  66 {
  67         unsigned long v, begin, end, linesz;
  68
  69         linesz = boot_cpu_data.icache.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                 invalidate_icache_line((void *)v);
  75 }
  76
  77 static inline void __flush_icache_range(unsigned long start, unsigned long end)
  78 {
  79         unsigned long v, linesz;
  80
  81         linesz = boot_cpu_data.dcache.linesz;
  82         for (v = start; v < end; v += linesz) {
  83                 clean_dcache_line((void *)v);
  84                 invalidate_icache_line((void *)v);
  85         }
  86
  87         flush_write_buffer();
  88 }
  89
  90 /*
  91  * This one is called after a module has been loaded.
  92  */
  93 void flush_icache_range(unsigned long start, unsigned long end)
  94 {
  95         unsigned long linesz;
  96
  97         linesz = boot_cpu_data.dcache.linesz;
  98         __flush_icache_range(start & ~(linesz - 1),
  99                              (end + linesz - 1) & ~(linesz - 1));
 100 }
 101
 102 /*
 103  * This one is called from do_no_page(), do_swap_page() and install_page().
 104  */
 105 void flush_icache_page(struct vm_area_struct *vma, struct page *page)
 106 {
 107         if (vma->vm_flags & VM_EXEC) {
 108                 void *v = kmap(page);
 109                 __flush_icache_range((unsigned long)v, (unsigned long)v + PAGE_SIZE);
 110                 kunmap(v);
 111         }
 112 }
 113
 114 /*
 115  * This one is used by copy_to_user_page()
 116  */
 117 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
 118                              unsigned long addr, int len)
 119 {
 120         if (vma->vm_flags & VM_EXEC)
 121                 flush_icache_range(addr, addr + len);
 122 }
 123
 124 asmlinkage int sys_cacheflush(int operation, void __user *addr, size_t len)
 125 {
 126         int ret;
 127
 128         if (len > CACHEFLUSH_MAX_LEN) {
 129                 ret = -EPERM;
 130                 if (!capable(CAP_SYS_ADMIN))
 131                         goto out;
 132         }
 133
 134         ret = -EFAULT;
 135         if (!access_ok(VERIFY_WRITE, addr, len))
 136                 goto out;
 137
 138         switch (operation) {
 139         case CACHE_IFLUSH:
 140                 flush_icache_range((unsigned long)addr,
 141                                    (unsigned long)addr + len);
 142                 ret = 0;
 143                 break;
 144         default:
 145                 ret = -EINVAL;
 146         }
 147
 148 out:
 149         return ret;
 150 }