/*
* Optimized xor_block operation for RAID4/5
*
* Copyright IBM Corp. 2016
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#include <linux/types.h>
#include <linux/export.h>
#include <linux/raid/xor.h>
static void xor_xc_2(unsigned long bytes, unsigned long *p1, unsigned long *p2)
{
asm volatile(
" larl 1,2f\n"
" aghi %0,-1\n"
" jm 3f\n"
" srlg 0,%0,8\n"
" ltgr 0,0\n"
" jz 1f\n"
"0: xc 0(256,%1),0(%2)\n"
" la %1,256(%1)\n"
" la %2,256(%2)\n"
" brctg 0,0b\n"
"1: ex %0,0(1)\n"
" j 3f\n"
"2: xc 0(1,%1),0(%2)\n"
"3:\n"
: : "d" (bytes), "a" (p1), "a" (p2)
: "0", "1", "cc", "memory");
}
static void xor_xc_3(unsigned long bytes, unsigned long *p1, unsigned long *p2,
unsigned long *p3)
{
asm volatile(
" larl 1,2f\n"
" aghi %0,-1\n"
" jm 3f\n"
" srlg 0,%0,8\n"
" ltgr 0,0\n"
" jz 1f\n"
"0: xc 0(256,%1),0(%2)\n"
" xc 0(256,%1),0(%3)\n"
" la %1,256(%1)\n"
" la %2,256(%2)\n"
" la %3,256(%3)\n"
" brctg 0,0b\n"
"1: ex %0,0(1)\n"
" ex %0,6(1)\n"
" j 3f\n"
"2: xc 0(1,%1),0(%2)\n"
" xc 0(1,%1),0(%3)\n"
"3:\n"
: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3)
: : "0", "1", "cc", "memory");
}
static void xor_xc_4(unsigned long bytes, unsigned long *p1, unsigned long *p2,
unsigned long *p3, unsigned long *p4)
{
asm volatile(
" larl 1,2f\n"
" aghi %0,-1\n"
" jm 3f\n"
" srlg 0,%0,8\n"
" ltgr 0,0\n"
" jz 1f\n"
"0: xc 0(256,%1),0(%2)\n"
" xc 0(256,%1),0(%3)\n"
" xc 0(256,%1),0(%4)\n"
" la %1,256(%1)\n"
" la %2,256(%2)\n"
" la %3,256(%3)\n"
" la %4,256(%4)\n"
" brctg 0,0b\n"
"1: ex %0,0(1)\n"
" ex %0,6(1)\n"
" ex %0,12(1)\n"
" j 3f\n"
"2: xc 0(1,%1),0(%2)\n"
" xc 0(1,%1),0(%3)\n"
" xc 0(1,%1),0(%4)\n"
"3:\n"
: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4)
: : "0", "1", "cc", "memory");
}
static void xor_xc_5(unsigned long bytes, unsigned long *p1, unsigned long *p2,
unsigned long *p3, unsigned long *p4, unsigned long *p5)
{
/* Get around a gcc oddity */
register unsigned long *reg7 asm ("7") = p5;
asm volatile(
" larl 1,2f\n"
" aghi %0,-1\n"
" jm 3f\n"
" srlg 0,%0,8\n"
" ltgr 0,0\n"
" jz 1f\n"
"0: xc 0(256,%1),0(%2)\n"
" xc 0(256,%1),0(%3)\n"
" xc 0(256,%1),0(%4)\n"
" xc 0(256,%1),0(%5)\n"
" la %1,256(%1)\n"
" la %2,256(%2)\n"
" la %3,256(%3)\n"
" la %4,256(%4)\n"
" la %5,256(%5)\n"
" brctg 0,0b\n"
"1: ex %0,0(1)\n"
" ex %0,6(1)\n"
" ex %0,12(1)\n"
" ex %0,18(1)\n"
" j 3f\n"
"2: xc 0(1,%1),0(%2)\n"
" xc 0(1,%1),0(%3)\n"
" xc 0(1,%1),0(%4)\n"
" xc 0(1,%1),0(%5)\n"
"3:\n"
: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4),
"+a" (reg7)
: : "0", "1", "cc", "memory");
}
struct xor_block_template xor_block_xc = {
.name = "xc",
.do_2 = xor_xc_2,
.do_3 = xor_xc_3,
.do_4 = xor_xc_4,
.do_5 = xor_xc_5,
};
EXPORT_SYMBOL(xor_block_xc);
