// 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 <[email protected]>
*
* This file is postprocessed using unroll.awk.
*/
#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
};