--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * RAID-6 syndrome calculation using RISC-V vector instructions
+ *
+ * Copyright 2024 Institute of Software, CAS.
+ * Author: Chunyan Zhang <zhangchunyan@iscas.ac.cn>
+ *
+ * Based on neon.uc:
+ *     Copyright 2002-2004 H. Peter Anvin
+ */
+
+#include <asm/simd.h>
+#include <asm/vector.h>
+#include <crypto/internal/simd.h>
+#include <linux/raid/pq.h>
+#include <linux/types.h>
+#include "rvv.h"
+
+#define NSIZE  (riscv_v_vsize / 32) /* NSIZE = vlenb */
+
+static int rvv_has_vector(void)
+{
+       return has_vector();
+}
+
+static void raid6_rvv1_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       unsigned long d;
+       int z, z0;
+       u8 *p, *q;
+
+       z0 = disks - 3;         /* Highest data disk */
+       p = dptr[z0 + 1];               /* XOR parity */
+       q = dptr[z0 + 2];               /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+        /* v0:wp0, v1:wq0, v2:wd0/w20, v3:w10 */
+       for (d = 0; d < bytes; d += NSIZE * 1) {
+               /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE])
+               );
+
+               for (z = z0 - 1 ; z >= 0 ; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] = wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] = wq$$;
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vse8.v   v0, (%[wp0])\n"
+                             "vse8.v   v1, (%[wq0])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0])
+               );
+       }
+}
+
+static void raid6_rvv1_xor_syndrome_real(int disks, int start, int stop,
+                                        unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       u8 *p, *q;
+       unsigned long d;
+       int z, z0;
+
+       z0 = stop;              /* P/Q right side optimization */
+       p = dptr[disks - 2];    /* XOR parity */
+       q = dptr[disks - 1];    /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /* v0:wp0, v1:wq0, v2:wd0/w20, v3:w10 */
+       for (d = 0 ; d < bytes ; d += NSIZE * 1) {
+               /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE])
+               );
+
+               /* P/Q data pages */
+               for (z = z0 - 1; z >= start; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /* P/Q left side optimization */
+               for (z = start - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * wq$$ = w1$$ ^ w2$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] ^= wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] ^= wq$$;
+                * v0:wp0, v1:wq0, v2:p0, v3:q0
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v2, (%[wp0])\n"
+                             "vle8.v   v3, (%[wq0])\n"
+                             "vxor.vv  v2, v2, v0\n"
+                             "vxor.vv  v3, v3, v1\n"
+                             "vse8.v   v2, (%[wp0])\n"
+                             "vse8.v   v3, (%[wq0])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0])
+               );
+       }
+}
+
+static void raid6_rvv2_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       unsigned long d;
+       int z, z0;
+       u8 *p, *q;
+
+       z0 = disks - 3;         /* Highest data disk */
+       p = dptr[z0 + 1];               /* XOR parity */
+       q = dptr[z0 + 2];               /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0, v1:wq0, v2:wd0/w20, v3:w10
+        * v4:wp1, v5:wq1, v6:wd1/w21, v7:w11
+        */
+       for (d = 0; d < bytes; d += NSIZE * 2) {
+               /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE])
+               );
+
+               for (z = z0 - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] = wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] = wq$$;
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vse8.v   v0, (%[wp0])\n"
+                             "vse8.v   v1, (%[wq0])\n"
+                             "vse8.v   v4, (%[wp1])\n"
+                             "vse8.v   v5, (%[wq1])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1])
+               );
+       }
+}
+
+static void raid6_rvv2_xor_syndrome_real(int disks, int start, int stop,
+                                        unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       u8 *p, *q;
+       unsigned long d;
+       int z, z0;
+
+       z0 = stop;              /* P/Q right side optimization */
+       p = dptr[disks - 2];    /* XOR parity */
+       q = dptr[disks - 1];    /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0, v1:wq0, v2:wd0/w20, v3:w10
+        * v4:wp1, v5:wq1, v6:wd1/w21, v7:w11
+        */
+       for (d = 0; d < bytes; d += NSIZE * 2) {
+                /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE])
+               );
+
+               /* P/Q data pages */
+               for (z = z0 - 1; z >= start; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /* P/Q left side optimization */
+               for (z = start - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * wq$$ = w1$$ ^ w2$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v1, v3, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] ^= wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] ^= wq$$;
+                * v0:wp0, v1:wq0, v2:p0, v3:q0
+                * v4:wp1, v5:wq1, v6:p1, v7:q1
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v2, (%[wp0])\n"
+                             "vle8.v   v3, (%[wq0])\n"
+                             "vxor.vv  v2, v2, v0\n"
+                             "vxor.vv  v3, v3, v1\n"
+                             "vse8.v   v2, (%[wp0])\n"
+                             "vse8.v   v3, (%[wq0])\n"
+
+                             "vle8.v   v6, (%[wp1])\n"
+                             "vle8.v   v7, (%[wq1])\n"
+                             "vxor.vv  v6, v6, v4\n"
+                             "vxor.vv  v7, v7, v5\n"
+                             "vse8.v   v6, (%[wp1])\n"
+                             "vse8.v   v7, (%[wq1])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1])
+               );
+       }
+}
+
+static void raid6_rvv4_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       unsigned long d;
+       int z, z0;
+       u8 *p, *q;
+
+       z0 = disks - 3; /* Highest data disk */
+       p = dptr[z0 + 1];       /* XOR parity */
+       q = dptr[z0 + 2];       /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0, v1:wq0, v2:wd0/w20, v3:w10
+        * v4:wp1, v5:wq1, v6:wd1/w21, v7:w11
+        * v8:wp2, v9:wq2, v10:wd2/w22, v11:w12
+        * v12:wp3, v13:wq3, v14:wd3/w23, v15:w13
+        */
+       for (d = 0; d < bytes; d += NSIZE * 4) {
+               /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             "vle8.v   v8, (%[wp2])\n"
+                             "vle8.v   v9, (%[wp2])\n"
+                             "vle8.v   v12, (%[wp3])\n"
+                             "vle8.v   v13, (%[wp3])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE]),
+                             [wp2]"r"(&dptr[z0][d + 2 * NSIZE]),
+                             [wp3]"r"(&dptr[z0][d + 3 * NSIZE])
+               );
+
+               for (z = z0 - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v11, v11, v10\n"
+                                     "vle8.v   v10, (%[wd2])\n"
+                                     "vxor.vv  v9, v11, v10\n"
+                                     "vxor.vv  v8, v8, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v15, v15, v14\n"
+                                     "vle8.v   v14, (%[wd3])\n"
+                                     "vxor.vv  v13, v15, v14\n"
+                                     "vxor.vv  v12, v12, v14\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [wd2]"r"(&dptr[z][d + 2 * NSIZE]),
+                                     [wd3]"r"(&dptr[z][d + 3 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] = wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] = wq$$;
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vse8.v   v0, (%[wp0])\n"
+                             "vse8.v   v1, (%[wq0])\n"
+                             "vse8.v   v4, (%[wp1])\n"
+                             "vse8.v   v5, (%[wq1])\n"
+                             "vse8.v   v8, (%[wp2])\n"
+                             "vse8.v   v9, (%[wq2])\n"
+                             "vse8.v   v12, (%[wp3])\n"
+                             "vse8.v   v13, (%[wq3])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1]),
+                             [wp2]"r"(&p[d + NSIZE * 2]),
+                             [wq2]"r"(&q[d + NSIZE * 2]),
+                             [wp3]"r"(&p[d + NSIZE * 3]),
+                             [wq3]"r"(&q[d + NSIZE * 3])
+               );
+       }
+}
+
+static void raid6_rvv4_xor_syndrome_real(int disks, int start, int stop,
+                                        unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       u8 *p, *q;
+       unsigned long d;
+       int z, z0;
+
+       z0 = stop;              /* P/Q right side optimization */
+       p = dptr[disks - 2];    /* XOR parity */
+       q = dptr[disks - 1];    /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0, v1:wq0, v2:wd0/w20, v3:w10
+        * v4:wp1, v5:wq1, v6:wd1/w21, v7:w11
+        * v8:wp2, v9:wq2, v10:wd2/w22, v11:w12
+        * v12:wp3, v13:wq3, v14:wd3/w23, v15:w13
+        */
+       for (d = 0; d < bytes; d += NSIZE * 4) {
+                /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             "vle8.v   v8, (%[wp2])\n"
+                             "vle8.v   v9, (%[wp2])\n"
+                             "vle8.v   v12, (%[wp3])\n"
+                             "vle8.v   v13, (%[wp3])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE]),
+                             [wp2]"r"(&dptr[z0][d + 2 * NSIZE]),
+                             [wp3]"r"(&dptr[z0][d + 3 * NSIZE])
+               );
+
+               /* P/Q data pages */
+               for (z = z0 - 1; z >= start; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v11, v11, v10\n"
+                                     "vle8.v   v10, (%[wd2])\n"
+                                     "vxor.vv  v9, v11, v10\n"
+                                     "vxor.vv  v8, v8, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v15, v15, v14\n"
+                                     "vle8.v   v14, (%[wd3])\n"
+                                     "vxor.vv  v13, v15, v14\n"
+                                     "vxor.vv  v12, v12, v14\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [wd2]"r"(&dptr[z][d + 2 * NSIZE]),
+                                     [wd3]"r"(&dptr[z][d + 3 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /* P/Q left side optimization */
+               for (z = start - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * wq$$ = w1$$ ^ w2$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v1, v3, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v5, v7, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v9, v11, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v13, v15, v14\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] ^= wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] ^= wq$$;
+                * v0:wp0, v1:wq0, v2:p0, v3:q0
+                * v4:wp1, v5:wq1, v6:p1, v7:q1
+                * v8:wp2, v9:wq2, v10:p2, v11:q2
+                * v12:wp3, v13:wq3, v14:p3, v15:q3
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v2, (%[wp0])\n"
+                             "vle8.v   v3, (%[wq0])\n"
+                             "vxor.vv  v2, v2, v0\n"
+                             "vxor.vv  v3, v3, v1\n"
+                             "vse8.v   v2, (%[wp0])\n"
+                             "vse8.v   v3, (%[wq0])\n"
+
+                             "vle8.v   v6, (%[wp1])\n"
+                             "vle8.v   v7, (%[wq1])\n"
+                             "vxor.vv  v6, v6, v4\n"
+                             "vxor.vv  v7, v7, v5\n"
+                             "vse8.v   v6, (%[wp1])\n"
+                             "vse8.v   v7, (%[wq1])\n"
+
+                             "vle8.v   v10, (%[wp2])\n"
+                             "vle8.v   v11, (%[wq2])\n"
+                             "vxor.vv  v10, v10, v8\n"
+                             "vxor.vv  v11, v11, v9\n"
+                             "vse8.v   v10, (%[wp2])\n"
+                             "vse8.v   v11, (%[wq2])\n"
+
+                             "vle8.v   v14, (%[wp3])\n"
+                             "vle8.v   v15, (%[wq3])\n"
+                             "vxor.vv  v14, v14, v12\n"
+                             "vxor.vv  v15, v15, v13\n"
+                             "vse8.v   v14, (%[wp3])\n"
+                             "vse8.v   v15, (%[wq3])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1]),
+                             [wp2]"r"(&p[d + NSIZE * 2]),
+                             [wq2]"r"(&q[d + NSIZE * 2]),
+                             [wp3]"r"(&p[d + NSIZE * 3]),
+                             [wq3]"r"(&q[d + NSIZE * 3])
+               );
+       }
+}
+
+static void raid6_rvv8_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       unsigned long d;
+       int z, z0;
+       u8 *p, *q;
+
+       z0 = disks - 3; /* Highest data disk */
+       p = dptr[z0 + 1];       /* XOR parity */
+       q = dptr[z0 + 2];       /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0,   v1:wq0,  v2:wd0/w20,  v3:w10
+        * v4:wp1,   v5:wq1,  v6:wd1/w21,  v7:w11
+        * v8:wp2,   v9:wq2, v10:wd2/w22, v11:w12
+        * v12:wp3, v13:wq3, v14:wd3/w23, v15:w13
+        * v16:wp4, v17:wq4, v18:wd4/w24, v19:w14
+        * v20:wp5, v21:wq5, v22:wd5/w25, v23:w15
+        * v24:wp6, v25:wq6, v26:wd6/w26, v27:w16
+        * v28:wp7, v29:wq7, v30:wd7/w27, v31:w17
+        */
+       for (d = 0; d < bytes; d += NSIZE * 8) {
+               /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             "vle8.v   v8, (%[wp2])\n"
+                             "vle8.v   v9, (%[wp2])\n"
+                             "vle8.v   v12, (%[wp3])\n"
+                             "vle8.v   v13, (%[wp3])\n"
+                             "vle8.v   v16, (%[wp4])\n"
+                             "vle8.v   v17, (%[wp4])\n"
+                             "vle8.v   v20, (%[wp5])\n"
+                             "vle8.v   v21, (%[wp5])\n"
+                             "vle8.v   v24, (%[wp6])\n"
+                             "vle8.v   v25, (%[wp6])\n"
+                             "vle8.v   v28, (%[wp7])\n"
+                             "vle8.v   v29, (%[wp7])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE]),
+                             [wp2]"r"(&dptr[z0][d + 2 * NSIZE]),
+                             [wp3]"r"(&dptr[z0][d + 3 * NSIZE]),
+                             [wp4]"r"(&dptr[z0][d + 4 * NSIZE]),
+                             [wp5]"r"(&dptr[z0][d + 5 * NSIZE]),
+                             [wp6]"r"(&dptr[z0][d + 6 * NSIZE]),
+                             [wp7]"r"(&dptr[z0][d + 7 * NSIZE])
+               );
+
+               for (z = z0 - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v11, v11, v10\n"
+                                     "vle8.v   v10, (%[wd2])\n"
+                                     "vxor.vv  v9, v11, v10\n"
+                                     "vxor.vv  v8, v8, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v15, v15, v14\n"
+                                     "vle8.v   v14, (%[wd3])\n"
+                                     "vxor.vv  v13, v15, v14\n"
+                                     "vxor.vv  v12, v12, v14\n"
+
+                                     "vsra.vi  v18, v17, 7\n"
+                                     "vsll.vi  v19, v17, 1\n"
+                                     "vand.vx  v18, v18, %[x1d]\n"
+                                     "vxor.vv  v19, v19, v18\n"
+                                     "vle8.v   v18, (%[wd4])\n"
+                                     "vxor.vv  v17, v19, v18\n"
+                                     "vxor.vv  v16, v16, v18\n"
+
+                                     "vsra.vi  v22, v21, 7\n"
+                                     "vsll.vi  v23, v21, 1\n"
+                                     "vand.vx  v22, v22, %[x1d]\n"
+                                     "vxor.vv  v23, v23, v22\n"
+                                     "vle8.v   v22, (%[wd5])\n"
+                                     "vxor.vv  v21, v23, v22\n"
+                                     "vxor.vv  v20, v20, v22\n"
+
+                                     "vsra.vi  v26, v25, 7\n"
+                                     "vsll.vi  v27, v25, 1\n"
+                                     "vand.vx  v26, v26, %[x1d]\n"
+                                     "vxor.vv  v27, v27, v26\n"
+                                     "vle8.v   v26, (%[wd6])\n"
+                                     "vxor.vv  v25, v27, v26\n"
+                                     "vxor.vv  v24, v24, v26\n"
+
+                                     "vsra.vi  v30, v29, 7\n"
+                                     "vsll.vi  v31, v29, 1\n"
+                                     "vand.vx  v30, v30, %[x1d]\n"
+                                     "vxor.vv  v31, v31, v30\n"
+                                     "vle8.v   v30, (%[wd7])\n"
+                                     "vxor.vv  v29, v31, v30\n"
+                                     "vxor.vv  v28, v28, v30\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [wd2]"r"(&dptr[z][d + 2 * NSIZE]),
+                                     [wd3]"r"(&dptr[z][d + 3 * NSIZE]),
+                                     [wd4]"r"(&dptr[z][d + 4 * NSIZE]),
+                                     [wd5]"r"(&dptr[z][d + 5 * NSIZE]),
+                                     [wd6]"r"(&dptr[z][d + 6 * NSIZE]),
+                                     [wd7]"r"(&dptr[z][d + 7 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] = wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] = wq$$;
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vse8.v   v0, (%[wp0])\n"
+                             "vse8.v   v1, (%[wq0])\n"
+                             "vse8.v   v4, (%[wp1])\n"
+                             "vse8.v   v5, (%[wq1])\n"
+                             "vse8.v   v8, (%[wp2])\n"
+                             "vse8.v   v9, (%[wq2])\n"
+                             "vse8.v   v12, (%[wp3])\n"
+                             "vse8.v   v13, (%[wq3])\n"
+                             "vse8.v   v16, (%[wp4])\n"
+                             "vse8.v   v17, (%[wq4])\n"
+                             "vse8.v   v20, (%[wp5])\n"
+                             "vse8.v   v21, (%[wq5])\n"
+                             "vse8.v   v24, (%[wp6])\n"
+                             "vse8.v   v25, (%[wq6])\n"
+                             "vse8.v   v28, (%[wp7])\n"
+                             "vse8.v   v29, (%[wq7])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1]),
+                             [wp2]"r"(&p[d + NSIZE * 2]),
+                             [wq2]"r"(&q[d + NSIZE * 2]),
+                             [wp3]"r"(&p[d + NSIZE * 3]),
+                             [wq3]"r"(&q[d + NSIZE * 3]),
+                             [wp4]"r"(&p[d + NSIZE * 4]),
+                             [wq4]"r"(&q[d + NSIZE * 4]),
+                             [wp5]"r"(&p[d + NSIZE * 5]),
+                             [wq5]"r"(&q[d + NSIZE * 5]),
+                             [wp6]"r"(&p[d + NSIZE * 6]),
+                             [wq6]"r"(&q[d + NSIZE * 6]),
+                             [wp7]"r"(&p[d + NSIZE * 7]),
+                             [wq7]"r"(&q[d + NSIZE * 7])
+               );
+       }
+}
+
+static void raid6_rvv8_xor_syndrome_real(int disks, int start, int stop,
+                                        unsigned long bytes, void **ptrs)
+{
+       u8 **dptr = (u8 **)ptrs;
+       u8 *p, *q;
+       unsigned long d;
+       int z, z0;
+
+       z0 = stop;              /* P/Q right side optimization */
+       p = dptr[disks - 2];    /* XOR parity */
+       q = dptr[disks - 1];    /* RS syndrome */
+
+       asm volatile (".option  push\n"
+                     ".option  arch,+v\n"
+                     "vsetvli  t0, x0, e8, m1, ta, ma\n"
+                     ".option  pop\n"
+       );
+
+       /*
+        * v0:wp0, v1:wq0, v2:wd0/w20, v3:w10
+        * v4:wp1, v5:wq1, v6:wd1/w21, v7:w11
+        * v8:wp2, v9:wq2, v10:wd2/w22, v11:w12
+        * v12:wp3, v13:wq3, v14:wd3/w23, v15:w13
+        * v16:wp4, v17:wq4, v18:wd4/w24, v19:w14
+        * v20:wp5, v21:wq5, v22:wd5/w25, v23:w15
+        * v24:wp6, v25:wq6, v26:wd6/w26, v27:w16
+        * v28:wp7, v29:wq7, v30:wd7/w27, v31:w17
+        */
+       for (d = 0; d < bytes; d += NSIZE * 8) {
+                /* wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v0, (%[wp0])\n"
+                             "vle8.v   v1, (%[wp0])\n"
+                             "vle8.v   v4, (%[wp1])\n"
+                             "vle8.v   v5, (%[wp1])\n"
+                             "vle8.v   v8, (%[wp2])\n"
+                             "vle8.v   v9, (%[wp2])\n"
+                             "vle8.v   v12, (%[wp3])\n"
+                             "vle8.v   v13, (%[wp3])\n"
+                             "vle8.v   v16, (%[wp4])\n"
+                             "vle8.v   v17, (%[wp4])\n"
+                             "vle8.v   v20, (%[wp5])\n"
+                             "vle8.v   v21, (%[wp5])\n"
+                             "vle8.v   v24, (%[wp6])\n"
+                             "vle8.v   v25, (%[wp6])\n"
+                             "vle8.v   v28, (%[wp7])\n"
+                             "vle8.v   v29, (%[wp7])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&dptr[z0][d + 0 * NSIZE]),
+                             [wp1]"r"(&dptr[z0][d + 1 * NSIZE]),
+                             [wp2]"r"(&dptr[z0][d + 2 * NSIZE]),
+                             [wp3]"r"(&dptr[z0][d + 3 * NSIZE]),
+                             [wp4]"r"(&dptr[z0][d + 4 * NSIZE]),
+                             [wp5]"r"(&dptr[z0][d + 5 * NSIZE]),
+                             [wp6]"r"(&dptr[z0][d + 6 * NSIZE]),
+                             [wp7]"r"(&dptr[z0][d + 7 * NSIZE])
+               );
+
+               /* P/Q data pages */
+               for (z = z0 - 1; z >= start; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * w1$$ ^= w2$$;
+                        * wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE];
+                        * wq$$ = w1$$ ^ wd$$;
+                        * wp$$ ^= wd$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v3, v3, v2\n"
+                                     "vle8.v   v2, (%[wd0])\n"
+                                     "vxor.vv  v1, v3, v2\n"
+                                     "vxor.vv  v0, v0, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v7, v7, v6\n"
+                                     "vle8.v   v6, (%[wd1])\n"
+                                     "vxor.vv  v5, v7, v6\n"
+                                     "vxor.vv  v4, v4, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v11, v11, v10\n"
+                                     "vle8.v   v10, (%[wd2])\n"
+                                     "vxor.vv  v9, v11, v10\n"
+                                     "vxor.vv  v8, v8, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v15, v15, v14\n"
+                                     "vle8.v   v14, (%[wd3])\n"
+                                     "vxor.vv  v13, v15, v14\n"
+                                     "vxor.vv  v12, v12, v14\n"
+
+                                     "vsra.vi  v18, v17, 7\n"
+                                     "vsll.vi  v19, v17, 1\n"
+                                     "vand.vx  v18, v18, %[x1d]\n"
+                                     "vxor.vv  v19, v19, v18\n"
+                                     "vle8.v   v18, (%[wd4])\n"
+                                     "vxor.vv  v17, v19, v18\n"
+                                     "vxor.vv  v16, v16, v18\n"
+
+                                     "vsra.vi  v22, v21, 7\n"
+                                     "vsll.vi  v23, v21, 1\n"
+                                     "vand.vx  v22, v22, %[x1d]\n"
+                                     "vxor.vv  v23, v23, v22\n"
+                                     "vle8.v   v22, (%[wd5])\n"
+                                     "vxor.vv  v21, v23, v22\n"
+                                     "vxor.vv  v20, v20, v22\n"
+
+                                     "vsra.vi  v26, v25, 7\n"
+                                     "vsll.vi  v27, v25, 1\n"
+                                     "vand.vx  v26, v26, %[x1d]\n"
+                                     "vxor.vv  v27, v27, v26\n"
+                                     "vle8.v   v26, (%[wd6])\n"
+                                     "vxor.vv  v25, v27, v26\n"
+                                     "vxor.vv  v24, v24, v26\n"
+
+                                     "vsra.vi  v30, v29, 7\n"
+                                     "vsll.vi  v31, v29, 1\n"
+                                     "vand.vx  v30, v30, %[x1d]\n"
+                                     "vxor.vv  v31, v31, v30\n"
+                                     "vle8.v   v30, (%[wd7])\n"
+                                     "vxor.vv  v29, v31, v30\n"
+                                     "vxor.vv  v28, v28, v30\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [wd0]"r"(&dptr[z][d + 0 * NSIZE]),
+                                     [wd1]"r"(&dptr[z][d + 1 * NSIZE]),
+                                     [wd2]"r"(&dptr[z][d + 2 * NSIZE]),
+                                     [wd3]"r"(&dptr[z][d + 3 * NSIZE]),
+                                     [wd4]"r"(&dptr[z][d + 4 * NSIZE]),
+                                     [wd5]"r"(&dptr[z][d + 5 * NSIZE]),
+                                     [wd6]"r"(&dptr[z][d + 6 * NSIZE]),
+                                     [wd7]"r"(&dptr[z][d + 7 * NSIZE]),
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /* P/Q left side optimization */
+               for (z = start - 1; z >= 0; z--) {
+                       /*
+                        * w2$$ = MASK(wq$$);
+                        * w1$$ = SHLBYTE(wq$$);
+                        * w2$$ &= NBYTES(0x1d);
+                        * wq$$ = w1$$ ^ w2$$;
+                        */
+                       asm volatile (".option  push\n"
+                                     ".option  arch,+v\n"
+                                     "vsra.vi  v2, v1, 7\n"
+                                     "vsll.vi  v3, v1, 1\n"
+                                     "vand.vx  v2, v2, %[x1d]\n"
+                                     "vxor.vv  v1, v3, v2\n"
+
+                                     "vsra.vi  v6, v5, 7\n"
+                                     "vsll.vi  v7, v5, 1\n"
+                                     "vand.vx  v6, v6, %[x1d]\n"
+                                     "vxor.vv  v5, v7, v6\n"
+
+                                     "vsra.vi  v10, v9, 7\n"
+                                     "vsll.vi  v11, v9, 1\n"
+                                     "vand.vx  v10, v10, %[x1d]\n"
+                                     "vxor.vv  v9, v11, v10\n"
+
+                                     "vsra.vi  v14, v13, 7\n"
+                                     "vsll.vi  v15, v13, 1\n"
+                                     "vand.vx  v14, v14, %[x1d]\n"
+                                     "vxor.vv  v13, v15, v14\n"
+
+                                     "vsra.vi  v18, v17, 7\n"
+                                     "vsll.vi  v19, v17, 1\n"
+                                     "vand.vx  v18, v18, %[x1d]\n"
+                                     "vxor.vv  v17, v19, v18\n"
+
+                                     "vsra.vi  v22, v21, 7\n"
+                                     "vsll.vi  v23, v21, 1\n"
+                                     "vand.vx  v22, v22, %[x1d]\n"
+                                     "vxor.vv  v21, v23, v22\n"
+
+                                     "vsra.vi  v26, v25, 7\n"
+                                     "vsll.vi  v27, v25, 1\n"
+                                     "vand.vx  v26, v26, %[x1d]\n"
+                                     "vxor.vv  v25, v27, v26\n"
+
+                                     "vsra.vi  v30, v29, 7\n"
+                                     "vsll.vi  v31, v29, 1\n"
+                                     "vand.vx  v30, v30, %[x1d]\n"
+                                     "vxor.vv  v29, v31, v30\n"
+                                     ".option  pop\n"
+                                     : :
+                                     [x1d]"r"(0x1d)
+                       );
+               }
+
+               /*
+                * *(unative_t *)&p[d+NSIZE*$$] ^= wp$$;
+                * *(unative_t *)&q[d+NSIZE*$$] ^= wq$$;
+                * v0:wp0, v1:wq0, v2:p0, v3:q0
+                * v4:wp1, v5:wq1, v6:p1, v7:q1
+                * v8:wp2, v9:wq2, v10:p2, v11:q2
+                * v12:wp3, v13:wq3, v14:p3, v15:q3
+                * v16:wp4, v17:wq4, v18:p4, v19:q4
+                * v20:wp5, v21:wq5, v22:p5, v23:q5
+                * v24:wp6, v25:wq6, v26:p6, v27:q6
+                * v28:wp7, v29:wq7, v30:p7, v31:q7
+                */
+               asm volatile (".option  push\n"
+                             ".option  arch,+v\n"
+                             "vle8.v   v2, (%[wp0])\n"
+                             "vle8.v   v3, (%[wq0])\n"
+                             "vxor.vv  v2, v2, v0\n"
+                             "vxor.vv  v3, v3, v1\n"
+                             "vse8.v   v2, (%[wp0])\n"
+                             "vse8.v   v3, (%[wq0])\n"
+
+                             "vle8.v   v6, (%[wp1])\n"
+                             "vle8.v   v7, (%[wq1])\n"
+                             "vxor.vv  v6, v6, v4\n"
+                             "vxor.vv  v7, v7, v5\n"
+                             "vse8.v   v6, (%[wp1])\n"
+                             "vse8.v   v7, (%[wq1])\n"
+
+                             "vle8.v   v10, (%[wp2])\n"
+                             "vle8.v   v11, (%[wq2])\n"
+                             "vxor.vv  v10, v10, v8\n"
+                             "vxor.vv  v11, v11, v9\n"
+                             "vse8.v   v10, (%[wp2])\n"
+                             "vse8.v   v11, (%[wq2])\n"
+
+                             "vle8.v   v14, (%[wp3])\n"
+                             "vle8.v   v15, (%[wq3])\n"
+                             "vxor.vv  v14, v14, v12\n"
+                             "vxor.vv  v15, v15, v13\n"
+                             "vse8.v   v14, (%[wp3])\n"
+                             "vse8.v   v15, (%[wq3])\n"
+
+                             "vle8.v   v18, (%[wp4])\n"
+                             "vle8.v   v19, (%[wq4])\n"
+                             "vxor.vv  v18, v18, v16\n"
+                             "vxor.vv  v19, v19, v17\n"
+                             "vse8.v   v18, (%[wp4])\n"
+                             "vse8.v   v19, (%[wq4])\n"
+
+                             "vle8.v   v22, (%[wp5])\n"
+                             "vle8.v   v23, (%[wq5])\n"
+                             "vxor.vv  v22, v22, v20\n"
+                             "vxor.vv  v23, v23, v21\n"
+                             "vse8.v   v22, (%[wp5])\n"
+                             "vse8.v   v23, (%[wq5])\n"
+
+                             "vle8.v   v26, (%[wp6])\n"
+                             "vle8.v   v27, (%[wq6])\n"
+                             "vxor.vv  v26, v26, v24\n"
+                             "vxor.vv  v27, v27, v25\n"
+                             "vse8.v   v26, (%[wp6])\n"
+                             "vse8.v   v27, (%[wq6])\n"
+
+                             "vle8.v   v30, (%[wp7])\n"
+                             "vle8.v   v31, (%[wq7])\n"
+                             "vxor.vv  v30, v30, v28\n"
+                             "vxor.vv  v31, v31, v29\n"
+                             "vse8.v   v30, (%[wp7])\n"
+                             "vse8.v   v31, (%[wq7])\n"
+                             ".option  pop\n"
+                             : :
+                             [wp0]"r"(&p[d + NSIZE * 0]),
+                             [wq0]"r"(&q[d + NSIZE * 0]),
+                             [wp1]"r"(&p[d + NSIZE * 1]),
+                             [wq1]"r"(&q[d + NSIZE * 1]),
+                             [wp2]"r"(&p[d + NSIZE * 2]),
+                             [wq2]"r"(&q[d + NSIZE * 2]),
+                             [wp3]"r"(&p[d + NSIZE * 3]),
+                             [wq3]"r"(&q[d + NSIZE * 3]),
+                             [wp4]"r"(&p[d + NSIZE * 4]),
+                             [wq4]"r"(&q[d + NSIZE * 4]),
+                             [wp5]"r"(&p[d + NSIZE * 5]),
+                             [wq5]"r"(&q[d + NSIZE * 5]),
+                             [wp6]"r"(&p[d + NSIZE * 6]),
+                             [wq6]"r"(&q[d + NSIZE * 6]),
+                             [wp7]"r"(&p[d + NSIZE * 7]),
+                             [wq7]"r"(&q[d + NSIZE * 7])
+               );
+       }
+}
+
+RAID6_RVV_WRAPPER(1);
+RAID6_RVV_WRAPPER(2);
+RAID6_RVV_WRAPPER(4);
+RAID6_RVV_WRAPPER(8);