Commit 204b885e authored Jul 29, 2008 by Joerg Roedel Committed by Linus Torvalds Jul 30, 2008

introduce lower_32_bits() macro



The file kernel.h contains the upper_32_bits macro.  This patch adds the
other part, the lower_32_bits macro.  Its first use will be in the driver
for AMD IOMMU.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 87547ee9

include/linux/kernel.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -75,6 +75,12 @@ extern const char linux_proc_banner[];
		*/
		#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))

		/**
		* lower_32_bits - return bits 0-31 of a number
		* @n: the number we're accessing
		*/
		#define lower_32_bits(n) ((u32)(n))

		#define KERN_EMERG "<0>" /* system is unusable */
		#define KERN_ALERT "<1>" /* action must be taken immediately */
		#define KERN_CRIT "<2>" /* critical conditions */