Merge commit 'c039c332f23e794deb6d6f37b9f07ff3b27fb2cf' into md

Pull in pre-requisites for adding raid10 support to dm-raid.

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/io.h b/include/linux/io.h
index 7fd2d2138bf..069e4075f87 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -67,4 +67,13 @@ int check_signature(const volatile void __iomem *io_addr,
 			const unsigned char *signature, int length);
 void devm_ioremap_release(struct device *dev, void *res);
 
+/*
+ * Some systems do not have legacy ISA devices.
+ * /dev/port is not a valid interface on these systems.
+ * So for those archs, <asm/io.h> should define the following symbol.
+ */
+#ifndef arch_has_dev_port
+#define arch_has_dev_port()     (1)
+#endif
+
 #endif /* _LINUX_IO_H */