LXR linux/lib/raid6/s390vx.uc

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * raid6_vx$#.c
   4 *
   5 * $#-way unrolled RAID6 gen/xor functions for s390
   6 * based on the vector facility
   7 *
   8 * Copyright IBM Corp. 2016
   9 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
  10 *
  11 * This file is postprocessed using unroll.awk.
  12 */
  13
  14#include <linux/raid/pq.h>
  15#include <asm/fpu/api.h>
  16
  17asm(".include \"asm/vx-insn.h\"\n");
  18
  19#define NSIZE 16
  20
  21static inline void LOAD_CONST(void)
  22{
  23        asm volatile("VREPIB %v24,7");
  24        asm volatile("VREPIB %v25,0x1d");
  25}
  26
  27/*
  28 * The SHLBYTE() operation shifts each of the 16 bytes in
  29 * vector register y left by 1 bit and stores the result in
  30 * vector register x.
  31 */
  32static inline void SHLBYTE(int x, int y)
  33{
  34        asm volatile ("VAB %0,%1,%1" : : "i" (x), "i" (y));
  35}
  36
  37/*
  38 * For each of the 16 bytes in the vector register y the MASK()
  39 * operation returns 0xFF if the high bit of the byte is 1,
  40 * or 0x00 if the high bit is 0. The result is stored in vector
  41 * register x.
  42 */
  43static inline void MASK(int x, int y)
  44{
  45        asm volatile ("VESRAVB  %0,%1,24" : : "i" (x), "i" (y));
  46}
  47
  48static inline void AND(int x, int y, int z)
  49{
  50        asm volatile ("VN %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
  51}
  52
  53static inline void XOR(int x, int y, int z)
  54{
  55        asm volatile ("VX %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
  56}
  57
  58static inline void LOAD_DATA(int x, u8 *ptr)
  59{
  60        typedef struct { u8 _[16 * $#]; } addrtype;
  61        register addrtype *__ptr asm("1") = (addrtype *) ptr;
  62
  63        asm volatile ("VLM %2,%3,0,%1"
  64                      : : "m" (*__ptr), "a" (__ptr), "i" (x),
  65                          "i" (x + $# - 1));
  66}
  67
  68static inline void STORE_DATA(int x, u8 *ptr)
  69{
  70        typedef struct { u8 _[16 * $#]; } addrtype;
  71        register addrtype *__ptr asm("1") = (addrtype *) ptr;
  72
  73        asm volatile ("VSTM %2,%3,0,1"
  74                      : "=m" (*__ptr) : "a" (__ptr), "i" (x),
  75                        "i" (x + $# - 1));
  76}
  77
  78static inline void COPY_VEC(int x, int y)
  79{
  80        asm volatile ("VLR %0,%1" : : "i" (x), "i" (y));
  81}
  82
  83static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
  84{
  85        struct kernel_fpu vxstate;
  86        u8 **dptr, *p, *q;
  87        int d, z, z0;
  88
  89        kernel_fpu_begin(&vxstate, KERNEL_VXR);
  90        LOAD_CONST();
  91
  92        dptr = (u8 **) ptrs;
  93        z0 = disks - 3;         /* Highest data disk */
  94        p = dptr[z0 + 1];       /* XOR parity */
  95        q = dptr[z0 + 2];       /* RS syndrome */
  96
  97        for (d = 0; d < bytes; d += $#*NSIZE) {
  98                LOAD_DATA(0,&dptr[z0][d]);
  99                COPY_VEC(8+$$,0+$$);
 100                for (z = z0 - 1; z >= 0; z--) {
 101                        MASK(16+$$,8+$$);
 102                        AND(16+$$,16+$$,25);
 103                        SHLBYTE(8+$$,8+$$);
 104                        XOR(8+$$,8+$$,16+$$);
 105                        LOAD_DATA(16,&dptr[z][d]);
 106                        XOR(0+$$,0+$$,16+$$);
 107                        XOR(8+$$,8+$$,16+$$);
 108                }
 109                STORE_DATA(0,&p[d]);
 110                STORE_DATA(8,&q[d]);
 111        }
 112        kernel_fpu_end(&vxstate, KERNEL_VXR);
 113}
 114
 115static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
 116                                        size_t bytes, void **ptrs)
 117{
 118        struct kernel_fpu vxstate;
 119        u8 **dptr, *p, *q;
 120        int d, z, z0;
 121
 122        dptr = (u8 **) ptrs;
 123        z0 = stop;              /* P/Q right side optimization */
 124        p = dptr[disks - 2];    /* XOR parity */
 125        q = dptr[disks - 1];    /* RS syndrome */
 126
 127        kernel_fpu_begin(&vxstate, KERNEL_VXR);
 128        LOAD_CONST();
 129
 130        for (d = 0; d < bytes; d += $#*NSIZE) {
 131                /* P/Q data pages */
 132                LOAD_DATA(0,&dptr[z0][d]);
 133                COPY_VEC(8+$$,0+$$);
 134                for (z = z0 - 1; z >= start; z--) {
 135                        MASK(16+$$,8+$$);
 136                        AND(16+$$,16+$$,25);
 137                        SHLBYTE(8+$$,8+$$);
 138                        XOR(8+$$,8+$$,16+$$);
 139                        LOAD_DATA(16,&dptr[z][d]);
 140                        XOR(0+$$,0+$$,16+$$);
 141                        XOR(8+$$,8+$$,16+$$);
 142                }
 143                /* P/Q left side optimization */
 144                for (z = start - 1; z >= 0; z--) {
 145                        MASK(16+$$,8+$$);
 146                        AND(16+$$,16+$$,25);
 147                        SHLBYTE(8+$$,8+$$);
 148                        XOR(8+$$,8+$$,16+$$);
 149                }
 150                LOAD_DATA(16,&p[d]);
 151                XOR(16+$$,16+$$,0+$$);
 152                STORE_DATA(16,&p[d]);
 153                LOAD_DATA(16,&q[d]);
 154                XOR(16+$$,16+$$,8+$$);
 155                STORE_DATA(16,&q[d]);
 156        }
 157        kernel_fpu_end(&vxstate, KERNEL_VXR);
 158}
 159
 160static int raid6_s390vx$#_valid(void)
 161{
 162        return MACHINE_HAS_VX;
 163}
 164
 165const struct raid6_calls raid6_s390vx$# = {
 166        raid6_s390vx$#_gen_syndrome,
 167        raid6_s390vx$#_xor_syndrome,
 168        raid6_s390vx$#_valid,
 169        "vx128x$#",
 170        1
 171};
 172