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#include <asm/vx-insn.h> 17 18#define NSIZE 16 19 20static 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 */ 31static 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 */ 42static inline void MASK(int x, int y) 43{ 44 asm volatile ("VESRAVB %0,%1,24" : : "i" (x), "i" (y)); 45} 46 47static 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 52static 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 57static inline void LOAD_DATA(int x, u8 *ptr) 58{ 59 typedef struct { u8 _[16 * $#]; } addrtype; 60 register addrtype *__ptr asm("1") = (addrtype *) ptr; 61 62 asm volatile ("VLM %2,%3,0,%1" 63 : : "m" (*__ptr), "a" (__ptr), "i" (x), 64 "i" (x + $# - 1)); 65} 66 67static inline void STORE_DATA(int x, u8 *ptr) 68{ 69 typedef struct { u8 _[16 * $#]; } addrtype; 70 register addrtype *__ptr asm("1") = (addrtype *) ptr; 71 72 asm volatile ("VSTM %2,%3,0,1" 73 : "=m" (*__ptr) : "a" (__ptr), "i" (x), 74 "i" (x + $# - 1)); 75} 76 77static inline void COPY_VEC(int x, int y) 78{ 79 asm volatile ("VLR %0,%1" : : "i" (x), "i" (y)); 80} 81 82static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs) 83{ 84 struct kernel_fpu vxstate; 85 u8 **dptr, *p, *q; 86 int d, z, z0; 87 88 kernel_fpu_begin(&vxstate, KERNEL_VXR); 89 LOAD_CONST(); 90 91 dptr = (u8 **) ptrs; 92 z0 = disks - 3; /* Highest data disk */ 93 p = dptr[z0 + 1]; /* XOR parity */ 94 q = dptr[z0 + 2]; /* RS syndrome */ 95 96 for (d = 0; d < bytes; d += $#*NSIZE) { 97 LOAD_DATA(0,&dptr[z0][d]); 98 COPY_VEC(8+$$,0+$$); 99 for (z = z0 - 1; z >= 0; z--) { 100 MASK(16+$$,8+$$); 101 AND(16+$$,16+$$,25); 102 SHLBYTE(8+$$,8+$$); 103 XOR(8+$$,8+$$,16+$$); 104 LOAD_DATA(16,&dptr[z][d]); 105 XOR(0+$$,0+$$,16+$$); 106 XOR(8+$$,8+$$,16+$$); 107 } 108 STORE_DATA(0,&p[d]); 109 STORE_DATA(8,&q[d]); 110 } 111 kernel_fpu_end(&vxstate, KERNEL_VXR); 112} 113 114static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop, 115 size_t bytes, void **ptrs) 116{ 117 struct kernel_fpu vxstate; 118 u8 **dptr, *p, *q; 119 int d, z, z0; 120 121 dptr = (u8 **) ptrs; 122 z0 = stop; /* P/Q right side optimization */ 123 p = dptr[disks - 2]; /* XOR parity */ 124 q = dptr[disks - 1]; /* RS syndrome */ 125 126 kernel_fpu_begin(&vxstate, KERNEL_VXR); 127 LOAD_CONST(); 128 129 for (d = 0; d < bytes; d += $#*NSIZE) { 130 /* P/Q data pages */ 131 LOAD_DATA(0,&dptr[z0][d]); 132 COPY_VEC(8+$$,0+$$); 133 for (z = z0 - 1; z >= start; z--) { 134 MASK(16+$$,8+$$); 135 AND(16+$$,16+$$,25); 136 SHLBYTE(8+$$,8+$$); 137 XOR(8+$$,8+$$,16+$$); 138 LOAD_DATA(16,&dptr[z][d]); 139 XOR(0+$$,0+$$,16+$$); 140 XOR(8+$$,8+$$,16+$$); 141 } 142 /* P/Q left side optimization */ 143 for (z = start - 1; z >= 0; z--) { 144 MASK(16+$$,8+$$); 145 AND(16+$$,16+$$,25); 146 SHLBYTE(8+$$,8+$$); 147 XOR(8+$$,8+$$,16+$$); 148 } 149 LOAD_DATA(16,&p[d]); 150 XOR(16+$$,16+$$,0+$$); 151 STORE_DATA(16,&p[d]); 152 LOAD_DATA(16,&q[d]); 153 XOR(16+$$,16+$$,8+$$); 154 STORE_DATA(16,&q[d]); 155 } 156 kernel_fpu_end(&vxstate, KERNEL_VXR); 157} 158 159static int raid6_s390vx$#_valid(void) 160{ 161 return cpu_has_vx(); 162} 163 164const struct raid6_calls raid6_s390vx$# = { 165 raid6_s390vx$#_gen_syndrome, 166 raid6_s390vx$#_xor_syndrome, 167 raid6_s390vx$#_valid, 168 "vx128x$#", 169 1 170}; 171