Logo Search packages:      
Sourcecode: linux version File versions  Download package

cache.c

/*
 * Copyright (C) 2004-2006 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/highmem.h>
#include <linux/unistd.h>

#include <asm/cacheflush.h>
#include <asm/cachectl.h>
#include <asm/processor.h>
#include <asm/uaccess.h>

/*
 * If you attempt to flush anything more than this, you need superuser
 * privileges.  The value is completely arbitrary.
 */
#define CACHEFLUSH_MAX_LEN    1024

void invalidate_dcache_region(void *start, size_t size)
{
      unsigned long v, begin, end, linesz, mask;

      linesz = boot_cpu_data.dcache.linesz;
      mask = linesz - 1;

      /* when first and/or last cachelines are shared, flush them
       * instead of invalidating ... never discard valid data!
       */
      begin = (unsigned long)start;
      end = begin + size;

      if (begin & mask) {
            flush_dcache_line(start);
            begin += linesz;
      }
      if (end & mask) {
            flush_dcache_line((void *)end);
            end &= ~mask;
      }

      /* remaining cachelines only need invalidation */
      for (v = begin; v < end; v += linesz)
            invalidate_dcache_line((void *)v);
      flush_write_buffer();
}

void clean_dcache_region(void *start, size_t size)
{
      unsigned long v, begin, end, linesz;

      linesz = boot_cpu_data.dcache.linesz;
      begin = (unsigned long)start & ~(linesz - 1);
      end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);

      for (v = begin; v < end; v += linesz)
            clean_dcache_line((void *)v);
      flush_write_buffer();
}

void flush_dcache_region(void *start, size_t size)
{
      unsigned long v, begin, end, linesz;

      linesz = boot_cpu_data.dcache.linesz;
      begin = (unsigned long)start & ~(linesz - 1);
      end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);

      for (v = begin; v < end; v += linesz)
            flush_dcache_line((void *)v);
      flush_write_buffer();
}

void invalidate_icache_region(void *start, size_t size)
{
      unsigned long v, begin, end, linesz;

      linesz = boot_cpu_data.icache.linesz;
      begin = (unsigned long)start & ~(linesz - 1);
      end = ((unsigned long)start + size + linesz - 1) & ~(linesz - 1);

      for (v = begin; v < end; v += linesz)
            invalidate_icache_line((void *)v);
}

static inline void __flush_icache_range(unsigned long start, unsigned long end)
{
      unsigned long v, linesz;

      linesz = boot_cpu_data.dcache.linesz;
      for (v = start; v < end; v += linesz) {
            clean_dcache_line((void *)v);
            invalidate_icache_line((void *)v);
      }

      flush_write_buffer();
}

/*
 * This one is called after a module has been loaded.
 */
void flush_icache_range(unsigned long start, unsigned long end)
{
      unsigned long linesz;

      linesz = boot_cpu_data.dcache.linesz;
      __flush_icache_range(start & ~(linesz - 1),
                       (end + linesz - 1) & ~(linesz - 1));
}

/*
 * This one is called from do_no_page(), do_swap_page() and install_page().
 */
void flush_icache_page(struct vm_area_struct *vma, struct page *page)
{
      if (vma->vm_flags & VM_EXEC) {
            void *v = page_address(page);
            __flush_icache_range((unsigned long)v, (unsigned long)v + PAGE_SIZE);
      }
}

asmlinkage int sys_cacheflush(int operation, void __user *addr, size_t len)
{
      int ret;

      if (len > CACHEFLUSH_MAX_LEN) {
            ret = -EPERM;
            if (!capable(CAP_SYS_ADMIN))
                  goto out;
      }

      ret = -EFAULT;
      if (!access_ok(VERIFY_WRITE, addr, len))
            goto out;

      switch (operation) {
      case CACHE_IFLUSH:
            flush_icache_range((unsigned long)addr,
                           (unsigned long)addr + len);
            ret = 0;
            break;
      default:
            ret = -EINVAL;
      }

out:
      return ret;
}

void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
            unsigned long vaddr, void *dst, const void *src,
            unsigned long len)
{
      memcpy(dst, src, len);
      if (vma->vm_flags & VM_EXEC)
            flush_icache_range((unsigned long)dst,
                        (unsigned long)dst + len);
}

Generated by  Doxygen 1.6.0   Back to index