x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/include/asm/edac.h

@@ -0,0 +1,18 @@
+#ifndef ASM_X86__EDAC_H
+#define ASM_X86__EDAC_H
+
+/* ECC atomic, DMA, SMP and interrupt safe scrub function */
+
+static inline void atomic_scrub(void *va, u32 size)
+{
+	u32 i, *virt_addr = va;
+
+	/*
+	 * Very carefully read and write to memory atomically so we
+	 * are interrupt, DMA and SMP safe.
+	 */
+	for (i = 0; i < size / 4; i++, virt_addr++)
+		asm volatile("lock; addl $0, %0"::"m" (*virt_addr));
+}
+
+#endif /* ASM_X86__EDAC_H */