| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Copyright IBM Corp. 2008, 2009 |
| * |
| * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>, |
| * |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/ftrace.h> |
| #include <asm/nospec-insn.h> |
| #include <asm/ptrace.h> |
| #include <asm/export.h> |
| |
| GEN_BR_THUNK %r1 |
| GEN_BR_THUNK %r14 |
| |
| .section .kprobes.text, "ax" |
| |
| ENTRY(ftrace_stub) |
| BR_EX %r14 |
| ENDPROC(ftrace_stub) |
| |
| #define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE) |
| #define STACK_PTREGS (STACK_FRAME_OVERHEAD) |
| #define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS) |
| #define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW) |
| #define STACK_PTREGS_ORIG_GPR2 (STACK_PTREGS + __PT_ORIG_GPR2) |
| #ifdef __PACK_STACK |
| /* allocate just enough for r14, r15 and backchain */ |
| #define TRACED_FUNC_FRAME_SIZE 24 |
| #else |
| #define TRACED_FUNC_FRAME_SIZE STACK_FRAME_OVERHEAD |
| #endif |
| |
| .macro ftrace_regs_entry, allregs=0 |
| stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller |
| |
| .if \allregs == 1 |
| lghi %r14,0 # save condition code |
| ipm %r14 # don't put any instructions |
| sllg %r14,%r14,16 # clobbering CC before this point |
| .endif |
| |
| lgr %r1,%r15 |
| # allocate stack frame for ftrace_caller to contain traced function |
| aghi %r15,-TRACED_FUNC_FRAME_SIZE |
| stg %r1,__SF_BACKCHAIN(%r15) |
| stg %r0,(__SF_GPRS+8*8)(%r15) |
| stg %r15,(__SF_GPRS+9*8)(%r15) |
| # allocate pt_regs and stack frame for ftrace_trace_function |
| aghi %r15,-STACK_FRAME_SIZE |
| stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15) |
| xc STACK_PTREGS_ORIG_GPR2(8,%r15),STACK_PTREGS_ORIG_GPR2(%r15) |
| |
| .if \allregs == 1 |
| stg %r14,(STACK_PTREGS_PSW)(%r15) |
| stosm (STACK_PTREGS_PSW)(%r15),0 |
| .endif |
| |
| lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address |
| aghi %r1,-TRACED_FUNC_FRAME_SIZE |
| stg %r1,__SF_BACKCHAIN(%r15) |
| stg %r0,(STACK_PTREGS_PSW+8)(%r15) |
| stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15) |
| .endm |
| |
| SYM_CODE_START(ftrace_regs_caller) |
| ftrace_regs_entry 1 |
| j ftrace_common |
| SYM_CODE_END(ftrace_regs_caller) |
| |
| SYM_CODE_START(ftrace_caller) |
| ftrace_regs_entry 0 |
| j ftrace_common |
| SYM_CODE_END(ftrace_caller) |
| |
| SYM_CODE_START(ftrace_common) |
| #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES |
| aghik %r2,%r0,-MCOUNT_INSN_SIZE |
| lgrl %r4,function_trace_op |
| lgrl %r1,ftrace_func |
| #else |
| lgr %r2,%r0 |
| aghi %r2,-MCOUNT_INSN_SIZE |
| larl %r4,function_trace_op |
| lg %r4,0(%r4) |
| larl %r1,ftrace_func |
| lg %r1,0(%r1) |
| #endif |
| lgr %r3,%r14 |
| la %r5,STACK_PTREGS(%r15) |
| BASR_EX %r14,%r1 |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| # The j instruction gets runtime patched to a nop instruction. |
| # See ftrace_enable_ftrace_graph_caller. |
| SYM_INNER_LABEL(ftrace_graph_caller, SYM_L_GLOBAL) |
| j .Lftrace_graph_caller_end |
| lmg %r2,%r3,(STACK_PTREGS_GPRS+14*8)(%r15) |
| lg %r4,(STACK_PTREGS_PSW+8)(%r15) |
| brasl %r14,prepare_ftrace_return |
| stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15) |
| .Lftrace_graph_caller_end: |
| #endif |
| lg %r0,(STACK_PTREGS_PSW+8)(%r15) |
| #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES |
| ltg %r1,STACK_PTREGS_ORIG_GPR2(%r15) |
| locgrz %r1,%r0 |
| #else |
| lg %r1,STACK_PTREGS_ORIG_GPR2(%r15) |
| ltgr %r1,%r1 |
| jnz 0f |
| lgr %r1,%r0 |
| #endif |
| 0: lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15) |
| BR_EX %r1 |
| SYM_CODE_END(ftrace_common) |
| |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| |
| SYM_FUNC_START(return_to_handler) |
| stmg %r2,%r5,32(%r15) |
| lgr %r1,%r15 |
| aghi %r15,-STACK_FRAME_OVERHEAD |
| stg %r1,__SF_BACKCHAIN(%r15) |
| brasl %r14,ftrace_return_to_handler |
| aghi %r15,STACK_FRAME_OVERHEAD |
| lgr %r14,%r2 |
| lmg %r2,%r5,32(%r15) |
| BR_EX %r14 |
| SYM_FUNC_END(return_to_handler) |
| |
| #endif |
