v4.19.13 snapshot.
diff --git a/lib/raid6/test/Makefile b/lib/raid6/test/Makefile
new file mode 100644
index 0000000..7977764
--- /dev/null
+++ b/lib/raid6/test/Makefile
@@ -0,0 +1,137 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# This is a simple Makefile to test some of the RAID-6 code
+# from userspace.
+#
+
+CC = gcc
+OPTFLAGS = -O2 # Adjust as desired
+CFLAGS = -I.. -I ../../../include -g $(OPTFLAGS)
+LD = ld
+AWK = awk -f
+AR = ar
+RANLIB = ranlib
+OBJS = int1.o int2.o int4.o int8.o int16.o int32.o recov.o algos.o tables.o
+
+ARCH := $(shell uname -m 2>/dev/null | sed -e /s/i.86/i386/)
+ifeq ($(ARCH),i386)
+ CFLAGS += -DCONFIG_X86_32
+ IS_X86 = yes
+endif
+ifeq ($(ARCH),x86_64)
+ CFLAGS += -DCONFIG_X86_64
+ IS_X86 = yes
+endif
+
+ifeq ($(ARCH),arm)
+ CFLAGS += -I../../../arch/arm/include -mfpu=neon
+ HAS_NEON = yes
+endif
+ifeq ($(ARCH),aarch64)
+ CFLAGS += -I../../../arch/arm64/include
+ HAS_NEON = yes
+endif
+
+ifeq ($(IS_X86),yes)
+ OBJS += mmx.o sse1.o sse2.o avx2.o recov_ssse3.o recov_avx2.o avx512.o recov_avx512.o
+ CFLAGS += $(shell echo "vpbroadcastb %xmm0, %ymm1" | \
+ gcc -c -x assembler - >&/dev/null && \
+ rm ./-.o && echo -DCONFIG_AS_AVX2=1)
+ CFLAGS += $(shell echo "vpmovm2b %k1, %zmm5" | \
+ gcc -c -x assembler - >&/dev/null && \
+ rm ./-.o && echo -DCONFIG_AS_AVX512=1)
+else ifeq ($(HAS_NEON),yes)
+ OBJS += neon.o neon1.o neon2.o neon4.o neon8.o recov_neon.o recov_neon_inner.o
+ CFLAGS += -DCONFIG_KERNEL_MODE_NEON=1
+else
+ HAS_ALTIVEC := $(shell printf '\#include <altivec.h>\nvector int a;\n' |\
+ gcc -c -x c - >/dev/null && rm ./-.o && echo yes)
+ ifeq ($(HAS_ALTIVEC),yes)
+ CFLAGS += -I../../../arch/powerpc/include
+ CFLAGS += -DCONFIG_ALTIVEC
+ OBJS += altivec1.o altivec2.o altivec4.o altivec8.o \
+ vpermxor1.o vpermxor2.o vpermxor4.o vpermxor8.o
+ endif
+endif
+
+.c.o:
+ $(CC) $(CFLAGS) -c -o $@ $<
+
+%.c: ../%.c
+ cp -f $< $@
+
+%.uc: ../%.uc
+ cp -f $< $@
+
+all: raid6.a raid6test
+
+raid6.a: $(OBJS)
+ rm -f $@
+ $(AR) cq $@ $^
+ $(RANLIB) $@
+
+raid6test: test.c raid6.a
+ $(CC) $(CFLAGS) -o raid6test $^
+
+neon1.c: neon.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=1 < neon.uc > $@
+
+neon2.c: neon.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=2 < neon.uc > $@
+
+neon4.c: neon.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=4 < neon.uc > $@
+
+neon8.c: neon.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=8 < neon.uc > $@
+
+altivec1.c: altivec.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=1 < altivec.uc > $@
+
+altivec2.c: altivec.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=2 < altivec.uc > $@
+
+altivec4.c: altivec.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=4 < altivec.uc > $@
+
+altivec8.c: altivec.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=8 < altivec.uc > $@
+
+vpermxor1.c: vpermxor.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=1 < vpermxor.uc > $@
+
+vpermxor2.c: vpermxor.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=2 < vpermxor.uc > $@
+
+vpermxor4.c: vpermxor.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=4 < vpermxor.uc > $@
+
+vpermxor8.c: vpermxor.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=8 < vpermxor.uc > $@
+
+int1.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=1 < int.uc > $@
+
+int2.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=2 < int.uc > $@
+
+int4.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=4 < int.uc > $@
+
+int8.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=8 < int.uc > $@
+
+int16.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=16 < int.uc > $@
+
+int32.c: int.uc ../unroll.awk
+ $(AWK) ../unroll.awk -vN=32 < int.uc > $@
+
+tables.c: mktables
+ ./mktables > tables.c
+
+clean:
+ rm -f *.o *.a mktables mktables.c *.uc int*.c altivec*.c vpermxor*.c neon*.c tables.c raid6test
+
+spotless: clean
+ rm -f *~
diff --git a/lib/raid6/test/test.c b/lib/raid6/test/test.c
new file mode 100644
index 0000000..b07f4d8
--- /dev/null
+++ b/lib/raid6/test/test.c
@@ -0,0 +1,156 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2 or (at your
+ * option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6test.c
+ *
+ * Test RAID-6 recovery with various algorithms
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <linux/raid/pq.h>
+
+#define NDISKS 16 /* Including P and Q */
+
+const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+struct raid6_calls raid6_call;
+
+char *dataptrs[NDISKS];
+char data[NDISKS][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+char recovi[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+char recovj[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+
+static void makedata(int start, int stop)
+{
+ int i, j;
+
+ for (i = start; i <= stop; i++) {
+ for (j = 0; j < PAGE_SIZE; j++)
+ data[i][j] = rand();
+
+ dataptrs[i] = data[i];
+ }
+}
+
+static char disk_type(int d)
+{
+ switch (d) {
+ case NDISKS-2:
+ return 'P';
+ case NDISKS-1:
+ return 'Q';
+ default:
+ return 'D';
+ }
+}
+
+static int test_disks(int i, int j)
+{
+ int erra, errb;
+
+ memset(recovi, 0xf0, PAGE_SIZE);
+ memset(recovj, 0xba, PAGE_SIZE);
+
+ dataptrs[i] = recovi;
+ dataptrs[j] = recovj;
+
+ raid6_dual_recov(NDISKS, PAGE_SIZE, i, j, (void **)&dataptrs);
+
+ erra = memcmp(data[i], recovi, PAGE_SIZE);
+ errb = memcmp(data[j], recovj, PAGE_SIZE);
+
+ if (i < NDISKS-2 && j == NDISKS-1) {
+ /* We don't implement the DQ failure scenario, since it's
+ equivalent to a RAID-5 failure (XOR, then recompute Q) */
+ erra = errb = 0;
+ } else {
+ printf("algo=%-8s faila=%3d(%c) failb=%3d(%c) %s\n",
+ raid6_call.name,
+ i, disk_type(i),
+ j, disk_type(j),
+ (!erra && !errb) ? "OK" :
+ !erra ? "ERRB" :
+ !errb ? "ERRA" : "ERRAB");
+ }
+
+ dataptrs[i] = data[i];
+ dataptrs[j] = data[j];
+
+ return erra || errb;
+}
+
+int main(int argc, char *argv[])
+{
+ const struct raid6_calls *const *algo;
+ const struct raid6_recov_calls *const *ra;
+ int i, j, p1, p2;
+ int err = 0;
+
+ makedata(0, NDISKS-1);
+
+ for (ra = raid6_recov_algos; *ra; ra++) {
+ if ((*ra)->valid && !(*ra)->valid())
+ continue;
+
+ raid6_2data_recov = (*ra)->data2;
+ raid6_datap_recov = (*ra)->datap;
+
+ printf("using recovery %s\n", (*ra)->name);
+
+ for (algo = raid6_algos; *algo; algo++) {
+ if ((*algo)->valid && !(*algo)->valid())
+ continue;
+
+ raid6_call = **algo;
+
+ /* Nuke syndromes */
+ memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
+
+ /* Generate assumed good syndrome */
+ raid6_call.gen_syndrome(NDISKS, PAGE_SIZE,
+ (void **)&dataptrs);
+
+ for (i = 0; i < NDISKS-1; i++)
+ for (j = i+1; j < NDISKS; j++)
+ err += test_disks(i, j);
+
+ if (!raid6_call.xor_syndrome)
+ continue;
+
+ for (p1 = 0; p1 < NDISKS-2; p1++)
+ for (p2 = p1; p2 < NDISKS-2; p2++) {
+
+ /* Simulate rmw run */
+ raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
+ (void **)&dataptrs);
+ makedata(p1, p2);
+ raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
+ (void **)&dataptrs);
+
+ for (i = 0; i < NDISKS-1; i++)
+ for (j = i+1; j < NDISKS; j++)
+ err += test_disks(i, j);
+ }
+
+ }
+ printf("\n");
+ }
+
+ printf("\n");
+ /* Pick the best algorithm test */
+ raid6_select_algo();
+
+ if (err)
+ printf("\n*** ERRORS FOUND ***\n");
+
+ return err;
+}