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-rw-r--r--lib/raid6/s390vx.uc135
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diff --git a/lib/raid6/s390vx.uc b/lib/raid6/s390vx.uc
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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * raid6_vx$#.c
+ *
+ * $#-way unrolled RAID6 gen/xor functions for s390
+ * based on the vector facility
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *
+ * This file is postprocessed using unroll.awk.
+ */
+
+#include <linux/cpufeature.h>
+#include <linux/raid/pq.h>
+#include <asm/fpu.h>
+
+#define NSIZE 16
+
+static __always_inline void LOAD_CONST(void)
+{
+ fpu_vrepib(24, 0x07);
+ fpu_vrepib(25, 0x1d);
+}
+
+/*
+ * The SHLBYTE() operation shifts each of the 16 bytes in
+ * vector register y left by 1 bit and stores the result in
+ * vector register x.
+ */
+#define SHLBYTE(x, y) fpu_vab(x, y, y)
+
+/*
+ * For each of the 16 bytes in the vector register y the MASK()
+ * operation returns 0xFF if the high bit of the byte is 1,
+ * or 0x00 if the high bit is 0. The result is stored in vector
+ * register x.
+ */
+#define MASK(x, y) fpu_vesravb(x, y, 24)
+
+#define AND(x, y, z) fpu_vn(x, y, z)
+#define XOR(x, y, z) fpu_vx(x, y, z)
+#define LOAD_DATA(x, ptr) fpu_vlm(x, x + $# - 1, ptr)
+#define STORE_DATA(x, ptr) fpu_vstm(x, x + $# - 1, ptr)
+#define COPY_VEC(x, y) fpu_vlr(x, y)
+
+static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ DECLARE_KERNEL_FPU_ONSTACK32(vxstate);
+ u8 **dptr, *p, *q;
+ int d, z, z0;
+
+ kernel_fpu_begin(&vxstate, KERNEL_VXR);
+ LOAD_CONST();
+
+ dptr = (u8 **) ptrs;
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0 + 1]; /* XOR parity */
+ q = dptr[z0 + 2]; /* RS syndrome */
+
+ for (d = 0; d < bytes; d += $#*NSIZE) {
+ LOAD_DATA(0,&dptr[z0][d]);
+ COPY_VEC(8+$$,0+$$);
+ for (z = z0 - 1; z >= 0; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ LOAD_DATA(16,&dptr[z][d]);
+ XOR(0+$$,0+$$,16+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ STORE_DATA(0,&p[d]);
+ STORE_DATA(8,&q[d]);
+ }
+ kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
+ size_t bytes, void **ptrs)
+{
+ DECLARE_KERNEL_FPU_ONSTACK32(vxstate);
+ u8 **dptr, *p, *q;
+ int d, z, z0;
+
+ dptr = (u8 **) ptrs;
+ z0 = stop; /* P/Q right side optimization */
+ p = dptr[disks - 2]; /* XOR parity */
+ q = dptr[disks - 1]; /* RS syndrome */
+
+ kernel_fpu_begin(&vxstate, KERNEL_VXR);
+ LOAD_CONST();
+
+ for (d = 0; d < bytes; d += $#*NSIZE) {
+ /* P/Q data pages */
+ LOAD_DATA(0,&dptr[z0][d]);
+ COPY_VEC(8+$$,0+$$);
+ for (z = z0 - 1; z >= start; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ LOAD_DATA(16,&dptr[z][d]);
+ XOR(0+$$,0+$$,16+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ /* P/Q left side optimization */
+ for (z = start - 1; z >= 0; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ LOAD_DATA(16,&p[d]);
+ XOR(16+$$,16+$$,0+$$);
+ STORE_DATA(16,&p[d]);
+ LOAD_DATA(16,&q[d]);
+ XOR(16+$$,16+$$,8+$$);
+ STORE_DATA(16,&q[d]);
+ }
+ kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static int raid6_s390vx$#_valid(void)
+{
+ return cpu_has_vx();
+}
+
+const struct raid6_calls raid6_s390vx$# = {
+ raid6_s390vx$#_gen_syndrome,
+ raid6_s390vx$#_xor_syndrome,
+ raid6_s390vx$#_valid,
+ "vx128x$#",
+ 1
+};