diff options
Diffstat (limited to 'arch/s390/kernel/mcount.S')
| -rw-r--r-- | arch/s390/kernel/mcount.S | 218 |
1 files changed, 165 insertions, 53 deletions
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S index 08dcf21cb8df..1fec370fecf4 100644 --- a/arch/s390/kernel/mcount.S +++ b/arch/s390/kernel/mcount.S @@ -1,73 +1,185 @@ +/* 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/march.h> + +#define STACK_FRAME_SIZE_PTREGS (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_FRAME_SIZE_FREGS (STACK_FRAME_OVERHEAD + __FTRACE_REGS_SIZE) +#define STACK_FREGS (STACK_FRAME_OVERHEAD) +#define STACK_FREGS_PTREGS (STACK_FRAME_OVERHEAD + __FTRACE_REGS_PT_REGS) +#define STACK_FREGS_PTREGS_GPRS (STACK_FREGS_PTREGS + __PT_GPRS) +#define STACK_FREGS_PTREGS_PSW (STACK_FREGS_PTREGS + __PT_PSW) +#define STACK_FREGS_PTREGS_ORIG_GPR2 (STACK_FREGS_PTREGS + __PT_ORIG_GPR2) +#define STACK_FREGS_PTREGS_FLAGS (STACK_FREGS_PTREGS + __PT_FLAGS) + +/* packed stack: allocate just enough for r14, r15 and backchain */ +#define TRACED_FUNC_FRAME_SIZE 24 + +#ifdef CONFIG_FUNCTION_TRACER + + GEN_BR_THUNK %r1 + GEN_BR_THUNK %r14 .section .kprobes.text, "ax" -ENTRY(ftrace_stub) - br %r14 +SYM_FUNC_START(ftrace_stub) + BR_EX %r14 +SYM_FUNC_END(ftrace_stub) + +SYM_CODE_START(ftrace_stub_direct_tramp) + lgr %r1, %r0 + BR_EX %r1 +SYM_CODE_END(ftrace_stub_direct_tramp) + + .macro ftrace_regs_entry, allregs=0 + stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller + + .if \allregs == 1 + # save psw mask + # don't put any instructions clobbering CC before this point + epsw %r1,%r14 + risbg %r14,%r1,0,31,32 + .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 ftrace_regs and stack frame for ftrace_trace_function + aghi %r15,-STACK_FRAME_SIZE_FREGS + stg %r1,(STACK_FREGS_PTREGS_GPRS+15*8)(%r15) + xc STACK_FREGS_PTREGS_ORIG_GPR2(8,%r15),STACK_FREGS_PTREGS_ORIG_GPR2(%r15) + + .if \allregs == 1 + stg %r14,(STACK_FREGS_PTREGS_PSW)(%r15) + mvghi STACK_FREGS_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS + .else + xc STACK_FREGS_PTREGS_FLAGS(8,%r15),STACK_FREGS_PTREGS_FLAGS(%r15) + .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_FREGS_PTREGS_PSW+8)(%r15) + stmg %r2,%r14,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15) + .endm -ENTRY(_mcount) -#ifdef CONFIG_DYNAMIC_FTRACE - br %r14 +SYM_CODE_START(ftrace_regs_caller) + ftrace_regs_entry 1 + j ftrace_common +SYM_CODE_END(ftrace_regs_caller) -ENTRY(ftrace_caller) +SYM_CODE_START(ftrace_caller) + ftrace_regs_entry 0 + j ftrace_common +SYM_CODE_END(ftrace_caller) + +SYM_CODE_START(ftrace_common) +#ifdef MARCH_HAS_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 - stm %r2,%r5,16(%r15) - bras %r1,2f -0: .long ftrace_trace_function -1: .long function_trace_stop -2: l %r2,1b-0b(%r1) - icm %r2,0xf,0(%r2) - jnz 3f - st %r14,56(%r15) - lr %r0,%r15 - ahi %r15,-96 - l %r3,100(%r15) - la %r2,0(%r14) - st %r0,__SF_BACKCHAIN(%r15) - la %r3,0(%r3) - ahi %r2,-MCOUNT_INSN_SIZE - l %r14,0b-0b(%r1) - l %r14,0(%r14) - basr %r14,%r14 -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - l %r2,100(%r15) - l %r3,152(%r15) -ENTRY(ftrace_graph_caller) -# The bras instruction gets runtime patched to call prepare_ftrace_return. -# See ftrace_enable_ftrace_graph_caller. The patched instruction is: -# bras %r14,prepare_ftrace_return - bras %r14,0f -0: st %r2,100(%r15) + lgr %r3,%r14 + la %r5,STACK_FREGS(%r15) + BASR_EX %r14,%r1 + lg %r0,(STACK_FREGS_PTREGS_PSW+8)(%r15) +#ifdef MARCH_HAS_Z196_FEATURES + ltg %r1,STACK_FREGS_PTREGS_ORIG_GPR2(%r15) + locgrz %r1,%r0 +#else + lg %r1,STACK_FREGS_PTREGS_ORIG_GPR2(%r15) + ltgr %r1,%r1 + jnz 0f + lgr %r1,%r0 #endif - ahi %r15,96 - l %r14,56(%r15) -3: lm %r2,%r5,16(%r15) - br %r14 +0: lmg %r2,%r15,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15) + BR_EX %r1 +SYM_CODE_END(ftrace_common) #ifdef CONFIG_FUNCTION_GRAPH_TRACER -ENTRY(return_to_handler) - stm %r2,%r5,16(%r15) - st %r14,56(%r15) - lr %r0,%r15 - ahi %r15,-96 - st %r0,__SF_BACKCHAIN(%r15) - bras %r1,0f - .long ftrace_return_to_handler -0: l %r2,0b-0b(%r1) - basr %r14,%r2 - lr %r14,%r2 - ahi %r15,96 - lm %r2,%r5,16(%r15) - br %r14 +SYM_FUNC_START(return_to_handler) + stmg %r2,%r5,32(%r15) + lgr %r1,%r15 + # allocate ftrace_regs and stack frame for ftrace_return_to_handler + aghi %r15,-STACK_FRAME_SIZE_FREGS + stg %r1,__SF_BACKCHAIN(%r15) + stg %r2,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15) + stg %r1,(STACK_FREGS_PTREGS_GPRS+15*8)(%r15) + la %r2,STACK_FRAME_OVERHEAD(%r15) + brasl %r14,ftrace_return_to_handler + aghi %r15,STACK_FRAME_SIZE_FREGS + lgr %r14,%r2 + lmg %r2,%r5,32(%r15) + BR_EX %r14 +SYM_FUNC_END(return_to_handler) #endif +#endif /* CONFIG_FUNCTION_TRACER */ + +SYM_CODE_START(ftrace_shared_hotpatch_trampoline_br) + lmg %r0,%r1,2(%r1) + br %r1 +SYM_INNER_LABEL(ftrace_shared_hotpatch_trampoline_br_end, SYM_L_GLOBAL) +SYM_CODE_END(ftrace_shared_hotpatch_trampoline_br) + +#ifdef CONFIG_EXPOLINE +SYM_CODE_START(ftrace_shared_hotpatch_trampoline_exrl) + lmg %r0,%r1,2(%r1) + exrl %r0,0f + j . +0: br %r1 +SYM_INNER_LABEL(ftrace_shared_hotpatch_trampoline_exrl_end, SYM_L_GLOBAL) +SYM_CODE_END(ftrace_shared_hotpatch_trampoline_exrl) +#endif /* CONFIG_EXPOLINE */ + +#ifdef CONFIG_RETHOOK + +SYM_CODE_START(arch_rethook_trampoline) + stg %r14,(__SF_GPRS+8*8)(%r15) + lay %r15,-STACK_FRAME_SIZE_PTREGS(%r15) + stmg %r0,%r14,STACK_PTREGS_GPRS(%r15) + + # store original stack pointer in backchain and pt_regs + lay %r7,STACK_FRAME_SIZE_PTREGS(%r15) + stg %r7,__SF_BACKCHAIN(%r15) + stg %r7,STACK_PTREGS_GPRS+(15*8)(%r15) + + # store full psw + epsw %r2,%r3 + risbg %r3,%r2,0,31,32 + stg %r3,STACK_PTREGS_PSW(%r15) + larl %r1,arch_rethook_trampoline + stg %r1,STACK_PTREGS_PSW+8(%r15) + + lay %r2,STACK_PTREGS(%r15) + brasl %r14,arch_rethook_trampoline_callback + + mvc __SF_EMPTY(16,%r7),STACK_PTREGS_PSW(%r15) + lmg %r0,%r15,STACK_PTREGS_GPRS(%r15) + lpswe __SF_EMPTY(%r15) +SYM_CODE_END(arch_rethook_trampoline) + +#endif /* CONFIG_RETHOOK */ |