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- /* SPDX-License-Identifier: GPL-2.0 */
- /*
- * Copyright IBM Corp. 2008, 2009
- *
- */
- #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>
- #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)
- #define STACK_PTREGS_FLAGS (STACK_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_EX %r14
- ENDPROC(ftrace_stub)
- .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 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)
- mvghi STACK_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS
- .else
- xc STACK_PTREGS_FLAGS(8,%r15),STACK_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_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
- #endif /* CONFIG_FUNCTION_TRACER */
- #ifdef CONFIG_KPROBES
- SYM_FUNC_START(__kretprobe_trampoline)
- stg %r14,(__SF_GPRS+8*8)(%r15)
- lay %r15,-STACK_FRAME_SIZE(%r15)
- stmg %r0,%r14,STACK_PTREGS_GPRS(%r15)
- # store original stack pointer in backchain and pt_regs
- lay %r7,STACK_FRAME_SIZE(%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,__kretprobe_trampoline
- stg %r1,STACK_PTREGS_PSW+8(%r15)
- lay %r2,STACK_PTREGS(%r15)
- brasl %r14,trampoline_probe_handler
- mvc __SF_EMPTY(16,%r7),STACK_PTREGS_PSW(%r15)
- lmg %r0,%r15,STACK_PTREGS_GPRS(%r15)
- lpswe __SF_EMPTY(%r15)
- SYM_FUNC_END(__kretprobe_trampoline)
- #endif /* CONFIG_KPROBES */
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