diff --git a/arch/x86/include/asm/xor.h b/arch/x86/include/asm/xor.h
index f8fde90..c661571 100644
--- a/arch/x86/include/asm/xor.h
+++ b/arch/x86/include/asm/xor.h
@@ -1,10 +1,327 @@
 #ifdef CONFIG_KMEMCHECK
 /* kmemcheck doesn't handle MMX/SSE/SSE2 instructions */
 # include <asm-generic/xor.h>
+#elif !defined(_ASM_X86_XOR_H)
+#define _ASM_X86_XOR_H
+
+/*
+ * Optimized RAID-5 checksumming functions for SSE.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * You should have received a copy of the GNU General Public License
+ * (for example /usr/src/linux/COPYING); if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * Cache avoiding checksumming functions utilizing KNI instructions
+ * Copyright (C) 1999 Zach Brown (with obvious credit due Ingo)
+ */
+
+/*
+ * Based on
+ * High-speed RAID5 checksumming functions utilizing SSE instructions.
+ * Copyright (C) 1998 Ingo Molnar.
+ */
+
+/*
+ * x86-64 changes / gcc fixes from Andi Kleen.
+ * Copyright 2002 Andi Kleen, SuSE Labs.
+ *
+ * This hasn't been optimized for the hammer yet, but there are likely
+ * no advantages to be gotten from x86-64 here anyways.
+ */
+
+#include <asm/i387.h>
+
+#ifdef CONFIG_X86_32
+/* reduce register pressure */
+# define XOR_CONSTANT_CONSTRAINT "i"
 #else
+# define XOR_CONSTANT_CONSTRAINT "re"
+#endif
+
+#define OFFS(x)		"16*("#x")"
+#define PF_OFFS(x)	"256+16*("#x")"
+#define PF0(x)		"	prefetchnta "PF_OFFS(x)"(%[p1])		;\n"
+#define LD(x, y)	"	movaps "OFFS(x)"(%[p1]), %%xmm"#y"	;\n"
+#define ST(x, y)	"	movaps %%xmm"#y", "OFFS(x)"(%[p1])	;\n"
+#define PF1(x)		"	prefetchnta "PF_OFFS(x)"(%[p2])		;\n"
+#define PF2(x)		"	prefetchnta "PF_OFFS(x)"(%[p3])		;\n"
+#define PF3(x)		"	prefetchnta "PF_OFFS(x)"(%[p4])		;\n"
+#define PF4(x)		"	prefetchnta "PF_OFFS(x)"(%[p5])		;\n"
+#define XO1(x, y)	"	xorps "OFFS(x)"(%[p2]), %%xmm"#y"	;\n"
+#define XO2(x, y)	"	xorps "OFFS(x)"(%[p3]), %%xmm"#y"	;\n"
+#define XO3(x, y)	"	xorps "OFFS(x)"(%[p4]), %%xmm"#y"	;\n"
+#define XO4(x, y)	"	xorps "OFFS(x)"(%[p5]), %%xmm"#y"	;\n"
+
+static void
+xor_sse_2(unsigned long bytes, unsigned long *p1, unsigned long *p2)
+{
+	unsigned long lines = bytes >> 8;
+
+	kernel_fpu_begin();
+
+	asm volatile(
+#undef BLOCK
+#define BLOCK(i)					\
+		LD(i, 0)				\
+			LD(i + 1, 1)			\
+		PF1(i)					\
+				PF1(i + 2)		\
+				LD(i + 2, 2)		\
+					LD(i + 3, 3)	\
+		PF0(i + 4)				\
+				PF0(i + 6)		\
+		XO1(i, 0)				\
+			XO1(i + 1, 1)			\
+				XO1(i + 2, 2)		\
+					XO1(i + 3, 3)	\
+		ST(i, 0)				\
+			ST(i + 1, 1)			\
+				ST(i + 2, 2)		\
+					ST(i + 3, 3)	\
+
+
+		PF0(0)
+				PF0(2)
+
+	" .align 32			;\n"
+	" 1:                            ;\n"
+
+		BLOCK(0)
+		BLOCK(4)
+		BLOCK(8)
+		BLOCK(12)
+
+	"       add %[inc], %[p1]       ;\n"
+	"       add %[inc], %[p2]       ;\n"
+	"       dec %[cnt]              ;\n"
+	"       jnz 1b                  ;\n"
+	: [cnt] "+r" (lines),
+	  [p1] "+r" (p1), [p2] "+r" (p2)
+	: [inc] XOR_CONSTANT_CONSTRAINT (256UL)
+	: "memory");
+
+	kernel_fpu_end();
+}
+
+static void
+xor_sse_3(unsigned long bytes, unsigned long *p1, unsigned long *p2,
+	  unsigned long *p3)
+{
+	unsigned long lines = bytes >> 8;
+
+	kernel_fpu_begin();
+
+	asm volatile(
+#undef BLOCK
+#define BLOCK(i) \
+		PF1(i)					\
+				PF1(i + 2)		\
+		LD(i, 0)				\
+			LD(i + 1, 1)			\
+				LD(i + 2, 2)		\
+					LD(i + 3, 3)	\
+		PF2(i)					\
+				PF2(i + 2)		\
+		PF0(i + 4)				\
+				PF0(i + 6)		\
+		XO1(i, 0)				\
+			XO1(i + 1, 1)			\
+				XO1(i + 2, 2)		\
+					XO1(i + 3, 3)	\
+		XO2(i, 0)				\
+			XO2(i + 1, 1)			\
+				XO2(i + 2, 2)		\
+					XO2(i + 3, 3)	\
+		ST(i, 0)				\
+			ST(i + 1, 1)			\
+				ST(i + 2, 2)		\
+					ST(i + 3, 3)	\
+
+
+		PF0(0)
+				PF0(2)
+
+	" .align 32			;\n"
+	" 1:                            ;\n"
+
+		BLOCK(0)
+		BLOCK(4)
+		BLOCK(8)
+		BLOCK(12)
+
+	"       add %[inc], %[p1]       ;\n"
+	"       add %[inc], %[p2]       ;\n"
+	"       add %[inc], %[p3]       ;\n"
+	"       dec %[cnt]              ;\n"
+	"       jnz 1b                  ;\n"
+	: [cnt] "+r" (lines),
+	  [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3)
+	: [inc] XOR_CONSTANT_CONSTRAINT (256UL)
+	: "memory");
+
+	kernel_fpu_end();
+}
+
+static void
+xor_sse_4(unsigned long bytes, unsigned long *p1, unsigned long *p2,
+	  unsigned long *p3, unsigned long *p4)
+{
+	unsigned long lines = bytes >> 8;
+
+	kernel_fpu_begin();
+
+	asm volatile(
+#undef BLOCK
+#define BLOCK(i) \
+		PF1(i)					\
+				PF1(i + 2)		\
+		LD(i, 0)				\
+			LD(i + 1, 1)			\
+				LD(i + 2, 2)		\
+					LD(i + 3, 3)	\
+		PF2(i)					\
+				PF2(i + 2)		\
+		XO1(i, 0)				\
+			XO1(i + 1, 1)			\
+				XO1(i + 2, 2)		\
+					XO1(i + 3, 3)	\
+		PF3(i)					\
+				PF3(i + 2)		\
+		PF0(i + 4)				\
+				PF0(i + 6)		\
+		XO2(i, 0)				\
+			XO2(i + 1, 1)			\
+				XO2(i + 2, 2)		\
+					XO2(i + 3, 3)	\
+		XO3(i, 0)				\
+			XO3(i + 1, 1)			\
+				XO3(i + 2, 2)		\
+					XO3(i + 3, 3)	\
+		ST(i, 0)				\
+			ST(i + 1, 1)			\
+				ST(i + 2, 2)		\
+					ST(i + 3, 3)	\
+
+
+		PF0(0)
+				PF0(2)
+
+	" .align 32			;\n"
+	" 1:                            ;\n"
+
+		BLOCK(0)
+		BLOCK(4)
+		BLOCK(8)
+		BLOCK(12)
+
+	"       add %[inc], %[p1]       ;\n"
+	"       add %[inc], %[p2]       ;\n"
+	"       add %[inc], %[p3]       ;\n"
+	"       add %[inc], %[p4]       ;\n"
+	"       dec %[cnt]              ;\n"
+	"       jnz 1b                  ;\n"
+	: [cnt] "+r" (lines), [p1] "+r" (p1),
+	  [p2] "+r" (p2), [p3] "+r" (p3), [p4] "+r" (p4)
+	: [inc] XOR_CONSTANT_CONSTRAINT (256UL)
+	: "memory");
+
+	kernel_fpu_end();
+}
+
+static void
+xor_sse_5(unsigned long bytes, unsigned long *p1, unsigned long *p2,
+	  unsigned long *p3, unsigned long *p4, unsigned long *p5)
+{
+	unsigned long lines = bytes >> 8;
+
+	kernel_fpu_begin();
+
+	asm volatile(
+#undef BLOCK
+#define BLOCK(i) \
+		PF1(i)					\
+				PF1(i + 2)		\
+		LD(i, 0)				\
+			LD(i + 1, 1)			\
+				LD(i + 2, 2)		\
+					LD(i + 3, 3)	\
+		PF2(i)					\
+				PF2(i + 2)		\
+		XO1(i, 0)				\
+			XO1(i + 1, 1)			\
+				XO1(i + 2, 2)		\
+					XO1(i + 3, 3)	\
+		PF3(i)					\
+				PF3(i + 2)		\
+		XO2(i, 0)				\
+			XO2(i + 1, 1)			\
+				XO2(i + 2, 2)		\
+					XO2(i + 3, 3)	\
+		PF4(i)					\
+				PF4(i + 2)		\
+		PF0(i + 4)				\
+				PF0(i + 6)		\
+		XO3(i, 0)				\
+			XO3(i + 1, 1)			\
+				XO3(i + 2, 2)		\
+					XO3(i + 3, 3)	\
+		XO4(i, 0)				\
+			XO4(i + 1, 1)			\
+				XO4(i + 2, 2)		\
+					XO4(i + 3, 3)	\
+		ST(i, 0)				\
+			ST(i + 1, 1)			\
+				ST(i + 2, 2)		\
+					ST(i + 3, 3)	\
+
+
+		PF0(0)
+				PF0(2)
+
+	" .align 32			;\n"
+	" 1:                            ;\n"
+
+		BLOCK(0)
+		BLOCK(4)
+		BLOCK(8)
+		BLOCK(12)
+
+	"       add %[inc], %[p1]       ;\n"
+	"       add %[inc], %[p2]       ;\n"
+	"       add %[inc], %[p3]       ;\n"
+	"       add %[inc], %[p4]       ;\n"
+	"       add %[inc], %[p5]       ;\n"
+	"       dec %[cnt]              ;\n"
+	"       jnz 1b                  ;\n"
+	: [cnt] "+r" (lines), [p1] "+r" (p1), [p2] "+r" (p2),
+	  [p3] "+r" (p3), [p4] "+r" (p4), [p5] "+r" (p5)
+	: [inc] XOR_CONSTANT_CONSTRAINT (256UL)
+	: "memory");
+
+	kernel_fpu_end();
+}
+
+#undef LD
+#undef XO1
+#undef XO2
+#undef XO3
+#undef XO4
+#undef ST
+#undef BLOCK
+
+#undef XOR_CONSTANT_CONSTRAINT
+
 #ifdef CONFIG_X86_32
 # include <asm/xor_32.h>
 #else
 # include <asm/xor_64.h>
 #endif
-#endif
+
+#endif /* _ASM_X86_XOR_H */