1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Copyright IBM Corp. 2008, 2009 4 * 5 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>, 6 * 7 */ 8 9#include <linux/linkage.h> 10#include <asm/asm-offsets.h> 11#include <asm/ftrace.h> 12#include <asm/nospec-insn.h> 13#include <asm/ptrace.h> 14#include <asm/export.h> 15 16 GEN_BR_THUNK %r1 17 GEN_BR_THUNK %r14 18 19 .section .kprobes.text, "ax" 20 21ENTRY(ftrace_stub) 22 BR_EX %r14 23 24#define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE) 25#define STACK_PTREGS (STACK_FRAME_OVERHEAD) 26#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS) 27#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW) 28 29ENTRY(_mcount) 30 BR_EX %r14 31 32EXPORT_SYMBOL(_mcount) 33 34ENTRY(ftrace_caller) 35 .globl ftrace_regs_caller 36 .set ftrace_regs_caller,ftrace_caller 37 lgr %r1,%r15 38#if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT)) 39 aghi %r0,MCOUNT_RETURN_FIXUP 40#endif 41 aghi %r15,-STACK_FRAME_SIZE 42 stg %r1,__SF_BACKCHAIN(%r15) 43 stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15) 44 stg %r0,(STACK_PTREGS_PSW+8)(%r15) 45 stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15) 46#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES 47 aghik %r2,%r0,-MCOUNT_INSN_SIZE 48 lgrl %r4,function_trace_op 49 lgrl %r1,ftrace_trace_function 50#else 51 lgr %r2,%r0 52 aghi %r2,-MCOUNT_INSN_SIZE 53 larl %r4,function_trace_op 54 lg %r4,0(%r4) 55 larl %r1,ftrace_trace_function 56 lg %r1,0(%r1) 57#endif 58 lgr %r3,%r14 59 la %r5,STACK_PTREGS(%r15) 60 BASR_EX %r14,%r1 61#ifdef CONFIG_FUNCTION_GRAPH_TRACER 62# The j instruction gets runtime patched to a nop instruction. 63# See ftrace_enable_ftrace_graph_caller. 64ENTRY(ftrace_graph_caller) 65 j ftrace_graph_caller_end 66 lg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 67 lg %r3,(STACK_PTREGS_PSW+8)(%r15) 68 brasl %r14,prepare_ftrace_return 69 stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) 70ftrace_graph_caller_end: 71 .globl ftrace_graph_caller_end 72#endif 73 lg %r1,(STACK_PTREGS_PSW+8)(%r15) 74 lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) 75 BR_EX %r1 76 77#ifdef CONFIG_FUNCTION_GRAPH_TRACER 78 79ENTRY(return_to_handler) 80 stmg %r2,%r5,32(%r15) 81 lgr %r1,%r15 82 aghi %r15,-STACK_FRAME_OVERHEAD 83 stg %r1,__SF_BACKCHAIN(%r15) 84 brasl %r14,ftrace_return_to_handler 85 aghi %r15,STACK_FRAME_OVERHEAD 86 lgr %r14,%r2 87 lmg %r2,%r5,32(%r15) 88 BR_EX %r14 89 90#endif 91