lib/raid6/s390vx.uc

   1 /*
   2  * raid6_vx$#.c
   3  *
   4  * $#-way unrolled RAID6 gen/xor functions for s390
   5  * based on the vector facility
   6  *
   7  * Copyright IBM Corp. 2016
   8  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   9  *
  10  * This file is postprocessed using unroll.awk.
  11  */
  12
  13 #include <linux/raid/pq.h>
  14 #include <asm/fpu/api.h>
  15
  16 asm(".include \"asm/vx-insn.h\"\n");
  17
  18 #define NSIZE 16
  19
  20 static inline void LOAD_CONST(void)
  21 {
  22         asm volatile("VREPIB %v24,7");
  23         asm volatile("VREPIB %v25,0x1d");
  24 }
  25
  26 /*
  27  * The SHLBYTE() operation shifts each of the 16 bytes in
  28  * vector register y left by 1 bit and stores the result in
  29  * vector register x.
  30  */
  31 static inline void SHLBYTE(int x, int y)
  32 {
  33         asm volatile ("VAB %0,%1,%1" : : "i" (x), "i" (y));
  34 }
  35
  36 /*
  37  * For each of the 16 bytes in the vector register y the MASK()
  38  * operation returns 0xFF if the high bit of the byte is 1,
  39  * or 0x00 if the high bit is 0. The result is stored in vector
  40  * register x.
  41  */
  42 static inline void MASK(int x, int y)
  43 {
  44         asm volatile ("VESRAVB  %0,%1,24" : : "i" (x), "i" (y));
  45 }
  46
  47 static inline void AND(int x, int y, int z)
  48 {
  49         asm volatile ("VN %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
  50 }
  51
  52 static inline void XOR(int x, int y, int z)
  53 {
  54         asm volatile ("VX %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
  55 }
  56
  57 static inline void LOAD_DATA(int x, int n, u8 *ptr)
  58 {
  59         typedef struct { u8 _[16*n]; } addrtype;
  60         register addrtype *__ptr asm("1") = (addrtype *) ptr;
  61
  62         asm volatile ("VLM %2,%3,0,%r1"
  63                       : : "m" (*__ptr), "a" (__ptr), "i" (x), "i" (x + n - 1));
  64 }
  65
  66 static inline void STORE_DATA(int x, int n, u8 *ptr)
  67 {
  68         typedef struct { u8 _[16*n]; } addrtype;
  69         register addrtype *__ptr asm("1") = (addrtype *) ptr;
  70
  71         asm volatile ("VSTM %2,%3,0,1"
  72                       : "=m" (*__ptr) : "a" (__ptr), "i" (x), "i" (x + n - 1));
  73 }
  74
  75 static inline void COPY_VEC(int x, int y)
  76 {
  77         asm volatile ("VLR %0,%1" : : "i" (x), "i" (y));
  78 }
  79
  80 static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
  81 {
  82         struct kernel_fpu vxstate;
  83         u8 **dptr, *p, *q;
  84         int d, z, z0;
  85
  86         kernel_fpu_begin(&vxstate, KERNEL_VXR);
  87         LOAD_CONST();
  88
  89         dptr = (u8 **) ptrs;
  90         z0 = disks - 3;         /* Highest data disk */
  91         p = dptr[z0 + 1];       /* XOR parity */
  92         q = dptr[z0 + 2];       /* RS syndrome */
  93
  94         for (d = 0; d < bytes; d += $#*NSIZE) {
  95                 LOAD_DATA(0,$#,&dptr[z0][d]);
  96                 COPY_VEC(8+$$,0+$$);
  97                 for (z = z0 - 1; z >= 0; z--) {
  98                         MASK(16+$$,8+$$);
  99                         AND(16+$$,16+$$,25);
 100                         SHLBYTE(8+$$,8+$$);
 101                         XOR(8+$$,8+$$,16+$$);
 102                         LOAD_DATA(16,$#,&dptr[z][d]);
 103                         XOR(0+$$,0+$$,16+$$);
 104                         XOR(8+$$,8+$$,16+$$);
 105                 }
 106                 STORE_DATA(0,$#,&p[d]);
 107                 STORE_DATA(8,$#,&q[d]);
 108         }
 109         kernel_fpu_end(&vxstate, KERNEL_VXR);
 110 }
 111
 112 static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
 113                                         size_t bytes, void **ptrs)
 114 {
 115         struct kernel_fpu vxstate;
 116         u8 **dptr, *p, *q;
 117         int d, z, z0;
 118
 119         dptr = (u8 **) ptrs;
 120         z0 = stop;              /* P/Q right side optimization */
 121         p = dptr[disks - 2];    /* XOR parity */
 122         q = dptr[disks - 1];    /* RS syndrome */
 123
 124         kernel_fpu_begin(&vxstate, KERNEL_VXR);
 125         LOAD_CONST();
 126
 127         for (d = 0; d < bytes; d += $#*NSIZE) {
 128                 /* P/Q data pages */
 129                 LOAD_DATA(0,$#,&dptr[z0][d]);
 130                 COPY_VEC(8+$$,0+$$);
 131                 for (z = z0 - 1; z >= start; z--) {
 132                         MASK(16+$$,8+$$);
 133                         AND(16+$$,16+$$,25);
 134                         SHLBYTE(8+$$,8+$$);
 135                         XOR(8+$$,8+$$,16+$$);
 136                         LOAD_DATA(16,$#,&dptr[z][d]);
 137                         XOR(0+$$,0+$$,16+$$);
 138                         XOR(8+$$,8+$$,16+$$);
 139                 }
 140                 /* P/Q left side optimization */
 141                 for (z = start - 1; z >= 0; z--) {
 142                         MASK(16+$$,8+$$);
 143                         AND(16+$$,16+$$,25);
 144                         SHLBYTE(8+$$,8+$$);
 145                         XOR(8+$$,8+$$,16+$$);
 146                 }
 147                 LOAD_DATA(16,$#,&p[d]);
 148                 XOR(16+$$,16+$$,0+$$);
 149                 STORE_DATA(16,$#,&p[d]);
 150                 LOAD_DATA(16,$#,&q[d]);
 151                 XOR(16+$$,16+$$,8+$$);
 152                 STORE_DATA(16,$#,&q[d]);
 153         }
 154         kernel_fpu_end(&vxstate, KERNEL_VXR);
 155 }
 156
 157 static int raid6_s390vx$#_valid(void)
 158 {
 159         return MACHINE_HAS_VX;
 160 }
 161
 162 const struct raid6_calls raid6_s390vx$# = {
 163         raid6_s390vx$#_gen_syndrome,
 164         raid6_s390vx$#_xor_syndrome,
 165         raid6_s390vx$#_valid,
 166         "vx128x$#",
 167         1
 168 };