LXR linux/lib/check

   1#include <linux/io.h>
   2#include <linux/module.h>
   3
   4/**
   5 *      check_signature         -       find BIOS signatures
   6 *      @io_addr: mmio address to check
   7 *      @signature:  signature block
   8 *      @length: length of signature
   9 *
  10 *      Perform a signature comparison with the mmio address io_addr. This
  11 *      address should have been obtained by ioremap.
  12 *      Returns 1 on a match.
  13 */
  14
  15int check_signature(const volatile void __iomem *io_addr,
  16                        const unsigned char *signature, int length)
  17{
  18        while (length--) {
  19                if (readb(io_addr) != *signature)
  20                        return 0;
  21                io_addr++;
  22                signature++;
  23        }
  24        return 1;
  25}
  26EXPORT_SYMBOL(check_signature);
  27