s390: move the XOR code to lib/raid/

Move the optimized XOR into lib/raid and include it it in xor.ko instead
of unconditionally building it into the main kernel image.

Link: https://lkml.kernel.org/r/20260327061704.3707577-19-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Sterba <dsterba@suse.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Li Nan <linan122@huawei.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

2 files changed, 135 insertions, 0 deletions

diff --git a/lib/raid/xor/Makefile b/lib/raid/xor/Makefile
index 3a7c887d08ee..3db6c2b2f26a 100644
--- a/lib/raid/xor/Makefile
+++ b/lib/raid/xor/Makefile
@@ -20,6 +20,7 @@ xor-$(CONFIG_ALTIVEC)		+= powerpc/xor_vmx.o powerpc/xor_vmx_glue.o
 xor-$(CONFIG_RISCV_ISA_V)	+= riscv/xor.o riscv/xor-glue.o
 xor-$(CONFIG_SPARC32)		+= sparc/xor-sparc32.o
 xor-$(CONFIG_SPARC64)		+= sparc/xor-sparc64.o sparc/xor-sparc64-glue.o
+xor-$(CONFIG_S390)		+= s390/xor.o
 
 
 CFLAGS_arm/xor-neon.o		+= $(CC_FLAGS_FPU)
diff --git a/lib/raid/xor/s390/xor.c b/lib/raid/xor/s390/xor.c
new file mode 100644
index 000000000000..acbd268adfc8
--- /dev/null
+++ b/lib/raid/xor/s390/xor.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Optimized xor_block operation for RAID4/5
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/raid/xor_impl.h>
+#include <asm/xor.h>
+
+static void xor_xc_2(unsigned long bytes, unsigned long * __restrict p1,
+		     const unsigned long * __restrict p2)
+{
+	asm volatile(
+		"	aghi	%0,-1\n"
+		"	jm	3f\n"
+		"	srlg	0,%0,8\n"
+		"	ltgr	0,0\n"
+		"	jz	1f\n"
+		"0:	xc	0(256,%1),0(%2)\n"
+		"	la	%1,256(%1)\n"
+		"	la	%2,256(%2)\n"
+		"	brctg	0,0b\n"
+		"1:	exrl	%0,2f\n"
+		"	j	3f\n"
+		"2:	xc	0(1,%1),0(%2)\n"
+		"3:"
+		: "+a" (bytes), "+a" (p1), "+a" (p2)
+		: : "0", "cc", "memory");
+}
+
+static void xor_xc_3(unsigned long bytes, unsigned long * __restrict p1,
+		     const unsigned long * __restrict p2,
+		     const unsigned long * __restrict p3)
+{
+	asm volatile(
+		"	aghi	%0,-1\n"
+		"	jm	4f\n"
+		"	srlg	0,%0,8\n"
+		"	ltgr	0,0\n"
+		"	jz	1f\n"
+		"0:	xc	0(256,%1),0(%2)\n"
+		"	xc	0(256,%1),0(%3)\n"
+		"	la	%1,256(%1)\n"
+		"	la	%2,256(%2)\n"
+		"	la	%3,256(%3)\n"
+		"	brctg	0,0b\n"
+		"1:	exrl	%0,2f\n"
+		"	exrl	%0,3f\n"
+		"	j	4f\n"
+		"2:	xc	0(1,%1),0(%2)\n"
+		"3:	xc	0(1,%1),0(%3)\n"
+		"4:"
+		: "+a" (bytes), "+a" (p1), "+a" (p2), "+a" (p3)
+		: : "0", "cc", "memory");
+}
+
+static void xor_xc_4(unsigned long bytes, unsigned long * __restrict p1,
+		     const unsigned long * __restrict p2,
+		     const unsigned long * __restrict p3,
+		     const unsigned long * __restrict p4)
+{
+	asm volatile(
+		"	aghi	%0,-1\n"
+		"	jm	5f\n"
+		"	srlg	0,%0,8\n"
+		"	ltgr	0,0\n"
+		"	jz	1f\n"
+		"0:	xc	0(256,%1),0(%2)\n"
+		"	xc	0(256,%1),0(%3)\n"
+		"	xc	0(256,%1),0(%4)\n"
+		"	la	%1,256(%1)\n"
+		"	la	%2,256(%2)\n"
+		"	la	%3,256(%3)\n"
+		"	la	%4,256(%4)\n"
+		"	brctg	0,0b\n"
+		"1:	exrl	%0,2f\n"
+		"	exrl	%0,3f\n"
+		"	exrl	%0,4f\n"
+		"	j	5f\n"
+		"2:	xc	0(1,%1),0(%2)\n"
+		"3:	xc	0(1,%1),0(%3)\n"
+		"4:	xc	0(1,%1),0(%4)\n"
+		"5:"
+		: "+a" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4)
+		: : "0", "cc", "memory");
+}
+
+static void xor_xc_5(unsigned long bytes, unsigned long * __restrict p1,
+		     const unsigned long * __restrict p2,
+		     const unsigned long * __restrict p3,
+		     const unsigned long * __restrict p4,
+		     const unsigned long * __restrict p5)
+{
+	asm volatile(
+		"	aghi	%0,-1\n"
+		"	jm	6f\n"
+		"	srlg	0,%0,8\n"
+		"	ltgr	0,0\n"
+		"	jz	1f\n"
+		"0:	xc	0(256,%1),0(%2)\n"
+		"	xc	0(256,%1),0(%3)\n"
+		"	xc	0(256,%1),0(%4)\n"
+		"	xc	0(256,%1),0(%5)\n"
+		"	la	%1,256(%1)\n"
+		"	la	%2,256(%2)\n"
+		"	la	%3,256(%3)\n"
+		"	la	%4,256(%4)\n"
+		"	la	%5,256(%5)\n"
+		"	brctg	0,0b\n"
+		"1:	exrl	%0,2f\n"
+		"	exrl	%0,3f\n"
+		"	exrl	%0,4f\n"
+		"	exrl	%0,5f\n"
+		"	j	6f\n"
+		"2:	xc	0(1,%1),0(%2)\n"
+		"3:	xc	0(1,%1),0(%3)\n"
+		"4:	xc	0(1,%1),0(%4)\n"
+		"5:	xc	0(1,%1),0(%5)\n"
+		"6:"
+		: "+a" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4),
+		  "+a" (p5)
+		: : "0", "cc", "memory");
+}
+
+struct xor_block_template xor_block_xc = {
+	.name = "xc",
+	.do_2 = xor_xc_2,
+	.do_3 = xor_xc_3,
+	.do_4 = xor_xc_4,
+	.do_5 = xor_xc_5,
+};