| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Userland implementation of getcpu() for 64 bits processes in a |
| * s390 kernel for use in the vDSO |
| * |
| * Copyright IBM Corp. 2016 |
| * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
| */ |
| #include <asm/vdso.h> |
| #include <asm/asm-offsets.h> |
| |
| .text |
| .align 4 |
| .globl __kernel_getcpu |
| .type __kernel_getcpu,@function |
| __kernel_getcpu: |
| .cfi_startproc |
| ear %r1,%a4 |
| llilh %r4,0x0100 |
| sar %a4,%r4 |
| la %r4,0 |
| epsw %r0,0 |
| sacf 512 |
| l %r5,__VDSO_CPU_NR(%r4) |
| l %r4,__VDSO_NODE_ID(%r4) |
| tml %r0,0x4000 |
| jo 1f |
| tml %r0,0x8000 |
| jno 0f |
| sacf 256 |
| j 1f |
| 0: sacf 0 |
| 1: sar %a4,%r1 |
| ltgr %r2,%r2 |
| jz 2f |
| st %r5,0(%r2) |
| 2: ltgr %r3,%r3 |
| jz 3f |
| st %r4,0(%r3) |
| 3: lghi %r2,0 |
| br %r14 |
| .cfi_endproc |
| .size __kernel_getcpu,.-__kernel_getcpu |
