diff --git a/lib/raid6/sse2.c b/lib/raid6/sse2.c
index 31acd59a0ef7ef92ec960ed64fffa233615ee973..1d2276b007ee1c7b502e6266f73f11a9e47e77aa 100644
--- a/lib/raid6/sse2.c
+++ b/lib/raid6/sse2.c
@@ -88,9 +88,58 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs)
 	kernel_fpu_end();
 }
 
+
+static void raid6_sse21_xor_syndrome(int disks, int start, int stop,
+				     size_t bytes, void **ptrs)
+ {
+	u8 **dptr = (u8 **)ptrs;
+	u8 *p, *q;
+	int d, z, z0;
+
+	z0 = stop;		/* P/Q right side optimization */
+	p = dptr[disks-2];	/* XOR parity */
+	q = dptr[disks-1];	/* RS syndrome */
+
+	kernel_fpu_begin();
+
+	asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0]));
+
+	for ( d = 0 ; d < bytes ; d += 16 ) {
+		asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d]));
+		asm volatile("movdqa %0,%%xmm2" : : "m" (p[d]));
+		asm volatile("pxor %xmm4,%xmm2");
+		/* P/Q data pages */
+		for ( z = z0-1 ; z >= start ; z-- ) {
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d]));
+			asm volatile("pxor %xmm5,%xmm2");
+			asm volatile("pxor %xmm5,%xmm4");
+		}
+		/* P/Q left side optimization */
+		for ( z = start-1 ; z >= 0 ; z-- ) {
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pxor %xmm5,%xmm4");
+		}
+		asm volatile("pxor %0,%%xmm4" : : "m" (q[d]));
+		/* Don't use movntdq for r/w memory area < cache line */
+		asm volatile("movdqa %%xmm4,%0" : "=m" (q[d]));
+		asm volatile("movdqa %%xmm2,%0" : "=m" (p[d]));
+	}
+
+	asm volatile("sfence" : : : "memory");
+	kernel_fpu_end();
+}
+
 const struct raid6_calls raid6_sse2x1 = {
 	raid6_sse21_gen_syndrome,
-	NULL,			/* XOR not yet implemented */
+	raid6_sse21_xor_syndrome,
 	raid6_have_sse2,
 	"sse2x1",
 	1			/* Has cache hints */
@@ -151,9 +200,76 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
 	kernel_fpu_end();
 }
 
+ static void raid6_sse22_xor_syndrome(int disks, int start, int stop,
+				     size_t bytes, void **ptrs)
+ {
+	u8 **dptr = (u8 **)ptrs;
+	u8 *p, *q;
+	int d, z, z0;
+
+	z0 = stop;		/* P/Q right side optimization */
+	p = dptr[disks-2];	/* XOR parity */
+	q = dptr[disks-1];	/* RS syndrome */
+
+	kernel_fpu_begin();
+
+	asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0]));
+
+	for ( d = 0 ; d < bytes ; d += 32 ) {
+		asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d]));
+		asm volatile("movdqa %0,%%xmm6" :: "m" (dptr[z0][d+16]));
+		asm volatile("movdqa %0,%%xmm2" : : "m" (p[d]));
+		asm volatile("movdqa %0,%%xmm3" : : "m" (p[d+16]));
+		asm volatile("pxor %xmm4,%xmm2");
+		asm volatile("pxor %xmm6,%xmm3");
+		/* P/Q data pages */
+		for ( z = z0-1 ; z >= start ; z-- ) {
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pxor %xmm7,%xmm7");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("pcmpgtb %xmm6,%xmm7");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("paddb %xmm6,%xmm6");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pand %xmm0,%xmm7");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+			asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d]));
+			asm volatile("movdqa %0,%%xmm7" :: "m" (dptr[z][d+16]));
+			asm volatile("pxor %xmm5,%xmm2");
+			asm volatile("pxor %xmm7,%xmm3");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+		}
+		/* P/Q left side optimization */
+		for ( z = start-1 ; z >= 0 ; z-- ) {
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pxor %xmm7,%xmm7");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("pcmpgtb %xmm6,%xmm7");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("paddb %xmm6,%xmm6");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pand %xmm0,%xmm7");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+		}
+		asm volatile("pxor %0,%%xmm4" : : "m" (q[d]));
+		asm volatile("pxor %0,%%xmm6" : : "m" (q[d+16]));
+		/* Don't use movntdq for r/w memory area < cache line */
+		asm volatile("movdqa %%xmm4,%0" : "=m" (q[d]));
+		asm volatile("movdqa %%xmm6,%0" : "=m" (q[d+16]));
+		asm volatile("movdqa %%xmm2,%0" : "=m" (p[d]));
+		asm volatile("movdqa %%xmm3,%0" : "=m" (p[d+16]));
+	}
+
+	asm volatile("sfence" : : : "memory");
+	kernel_fpu_end();
+ }
+
 const struct raid6_calls raid6_sse2x2 = {
 	raid6_sse22_gen_syndrome,
-	NULL,			/* XOR not yet implemented */
+	raid6_sse22_xor_syndrome,
 	raid6_have_sse2,
 	"sse2x2",
 	1			/* Has cache hints */
@@ -250,9 +366,117 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
 	kernel_fpu_end();
 }
 
+ static void raid6_sse24_xor_syndrome(int disks, int start, int stop,
+				     size_t bytes, void **ptrs)
+ {
+	u8 **dptr = (u8 **)ptrs;
+	u8 *p, *q;
+	int d, z, z0;
+
+	z0 = stop;		/* P/Q right side optimization */
+	p = dptr[disks-2];	/* XOR parity */
+	q = dptr[disks-1];	/* RS syndrome */
+
+	kernel_fpu_begin();
+
+	asm volatile("movdqa %0,%%xmm0" :: "m" (raid6_sse_constants.x1d[0]));
+
+	for ( d = 0 ; d < bytes ; d += 64 ) {
+		asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d]));
+		asm volatile("movdqa %0,%%xmm6" :: "m" (dptr[z0][d+16]));
+		asm volatile("movdqa %0,%%xmm12" :: "m" (dptr[z0][d+32]));
+		asm volatile("movdqa %0,%%xmm14" :: "m" (dptr[z0][d+48]));
+		asm volatile("movdqa %0,%%xmm2" : : "m" (p[d]));
+		asm volatile("movdqa %0,%%xmm3" : : "m" (p[d+16]));
+		asm volatile("movdqa %0,%%xmm10" : : "m" (p[d+32]));
+		asm volatile("movdqa %0,%%xmm11" : : "m" (p[d+48]));
+		asm volatile("pxor %xmm4,%xmm2");
+		asm volatile("pxor %xmm6,%xmm3");
+		asm volatile("pxor %xmm12,%xmm10");
+		asm volatile("pxor %xmm14,%xmm11");
+		/* P/Q data pages */
+		for ( z = z0-1 ; z >= start ; z-- ) {
+			asm volatile("prefetchnta %0" :: "m" (dptr[z][d]));
+			asm volatile("prefetchnta %0" :: "m" (dptr[z][d+32]));
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pxor %xmm7,%xmm7");
+			asm volatile("pxor %xmm13,%xmm13");
+			asm volatile("pxor %xmm15,%xmm15");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("pcmpgtb %xmm6,%xmm7");
+			asm volatile("pcmpgtb %xmm12,%xmm13");
+			asm volatile("pcmpgtb %xmm14,%xmm15");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("paddb %xmm6,%xmm6");
+			asm volatile("paddb %xmm12,%xmm12");
+			asm volatile("paddb %xmm14,%xmm14");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pand %xmm0,%xmm7");
+			asm volatile("pand %xmm0,%xmm13");
+			asm volatile("pand %xmm0,%xmm15");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+			asm volatile("pxor %xmm13,%xmm12");
+			asm volatile("pxor %xmm15,%xmm14");
+			asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d]));
+			asm volatile("movdqa %0,%%xmm7" :: "m" (dptr[z][d+16]));
+			asm volatile("movdqa %0,%%xmm13" :: "m" (dptr[z][d+32]));
+			asm volatile("movdqa %0,%%xmm15" :: "m" (dptr[z][d+48]));
+			asm volatile("pxor %xmm5,%xmm2");
+			asm volatile("pxor %xmm7,%xmm3");
+			asm volatile("pxor %xmm13,%xmm10");
+			asm volatile("pxor %xmm15,%xmm11");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+			asm volatile("pxor %xmm13,%xmm12");
+			asm volatile("pxor %xmm15,%xmm14");
+		}
+		asm volatile("prefetchnta %0" :: "m" (q[d]));
+		asm volatile("prefetchnta %0" :: "m" (q[d+32]));
+		/* P/Q left side optimization */
+		for ( z = start-1 ; z >= 0 ; z-- ) {
+			asm volatile("pxor %xmm5,%xmm5");
+			asm volatile("pxor %xmm7,%xmm7");
+			asm volatile("pxor %xmm13,%xmm13");
+			asm volatile("pxor %xmm15,%xmm15");
+			asm volatile("pcmpgtb %xmm4,%xmm5");
+			asm volatile("pcmpgtb %xmm6,%xmm7");
+			asm volatile("pcmpgtb %xmm12,%xmm13");
+			asm volatile("pcmpgtb %xmm14,%xmm15");
+			asm volatile("paddb %xmm4,%xmm4");
+			asm volatile("paddb %xmm6,%xmm6");
+			asm volatile("paddb %xmm12,%xmm12");
+			asm volatile("paddb %xmm14,%xmm14");
+			asm volatile("pand %xmm0,%xmm5");
+			asm volatile("pand %xmm0,%xmm7");
+			asm volatile("pand %xmm0,%xmm13");
+			asm volatile("pand %xmm0,%xmm15");
+			asm volatile("pxor %xmm5,%xmm4");
+			asm volatile("pxor %xmm7,%xmm6");
+			asm volatile("pxor %xmm13,%xmm12");
+			asm volatile("pxor %xmm15,%xmm14");
+		}
+		asm volatile("movntdq %%xmm2,%0" : "=m" (p[d]));
+		asm volatile("movntdq %%xmm3,%0" : "=m" (p[d+16]));
+		asm volatile("movntdq %%xmm10,%0" : "=m" (p[d+32]));
+		asm volatile("movntdq %%xmm11,%0" : "=m" (p[d+48]));
+		asm volatile("pxor %0,%%xmm4" : : "m" (q[d]));
+		asm volatile("pxor %0,%%xmm6" : : "m" (q[d+16]));
+		asm volatile("pxor %0,%%xmm12" : : "m" (q[d+32]));
+		asm volatile("pxor %0,%%xmm14" : : "m" (q[d+48]));
+		asm volatile("movntdq %%xmm4,%0" : "=m" (q[d]));
+		asm volatile("movntdq %%xmm6,%0" : "=m" (q[d+16]));
+		asm volatile("movntdq %%xmm12,%0" : "=m" (q[d+32]));
+		asm volatile("movntdq %%xmm14,%0" : "=m" (q[d+48]));
+	}
+	asm volatile("sfence" : : : "memory");
+	kernel_fpu_end();
+ }
+
+
 const struct raid6_calls raid6_sse2x4 = {
 	raid6_sse24_gen_syndrome,
-	NULL,			/* XOR not yet implemented */
+	raid6_sse24_xor_syndrome,
 	raid6_have_sse2,
 	"sse2x4",
 	1			/* Has cache hints */