uninline check_signature()
This is a rather bizarre thing to have inlined in io.h. Stick it in lib/
instead.
While we're there, despaghetti it a bit, and fix its off-by-one behaviour when
passed a zero length.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/check_signature.c b/lib/check_signature.c
new file mode 100644
index 0000000..fd6af19
--- /dev/null
+++ b/lib/check_signature.c
@@ -0,0 +1,26 @@
+#include <linux/io.h>
+#include <linux/module.h>
+
+/**
+ * check_signature - find BIOS signatures
+ * @io_addr: mmio address to check
+ * @signature: signature block
+ * @length: length of signature
+ *
+ * Perform a signature comparison with the mmio address io_addr. This
+ * address should have been obtained by ioremap.
+ * Returns 1 on a match.
+ */
+
+int check_signature(const volatile void __iomem *io_addr,
+ const unsigned char *signature, int length)
+{
+ while (length--) {
+ if (readb(io_addr) != *signature)
+ return 0;
+ io_addr++;
+ signature++;
+ }
+ return 1;
+}
+EXPORT_SYMBOL(check_signature);
