1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright IBM Corp. 2008, 2009
5 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
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>
19 .section .kprobes.text, "ax"
25 #define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE)
26 #define STACK_PTREGS (STACK_FRAME_OVERHEAD)
27 #define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
28 #define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
29 #define STACK_PTREGS_ORIG_GPR2 (STACK_PTREGS + __PT_ORIG_GPR2)
30 #define STACK_PTREGS_FLAGS (STACK_PTREGS + __PT_FLAGS)
32 /* allocate just enough for r14, r15 and backchain */
33 #define TRACED_FUNC_FRAME_SIZE 24
35 #define TRACED_FUNC_FRAME_SIZE STACK_FRAME_OVERHEAD
38 .macro ftrace_regs_entry, allregs=0
39 stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller
42 lghi %r14,0 # save condition code
43 ipm %r14 # don't put any instructions
44 sllg %r14,%r14,16 # clobbering CC before this point
48 # allocate stack frame for ftrace_caller to contain traced function
49 aghi %r15,-TRACED_FUNC_FRAME_SIZE
50 stg %r1,__SF_BACKCHAIN(%r15)
51 stg %r0,(__SF_GPRS+8*8)(%r15)
52 stg %r15,(__SF_GPRS+9*8)(%r15)
53 # allocate pt_regs and stack frame for ftrace_trace_function
54 aghi %r15,-STACK_FRAME_SIZE
55 stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15)
56 xc STACK_PTREGS_ORIG_GPR2(8,%r15),STACK_PTREGS_ORIG_GPR2(%r15)
59 stg %r14,(STACK_PTREGS_PSW)(%r15)
60 stosm (STACK_PTREGS_PSW)(%r15),0
61 #ifdef CONFIG_HAVE_MARCH_Z10_FEATURES
62 mvghi STACK_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS
64 lghi %r14,_PIF_FTRACE_FULL_REGS
65 stg %r14,STACK_PTREGS_FLAGS(%r15)
68 xc STACK_PTREGS_FLAGS(8,%r15),STACK_PTREGS_FLAGS(%r15)
71 lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address
72 aghi %r1,-TRACED_FUNC_FRAME_SIZE
73 stg %r1,__SF_BACKCHAIN(%r15)
74 stg %r0,(STACK_PTREGS_PSW+8)(%r15)
75 stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15)
78 SYM_CODE_START(ftrace_regs_caller)
81 SYM_CODE_END(ftrace_regs_caller)
83 SYM_CODE_START(ftrace_caller)
86 SYM_CODE_END(ftrace_caller)
88 SYM_CODE_START(ftrace_common)
89 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
90 aghik %r2,%r0,-MCOUNT_INSN_SIZE
91 lgrl %r4,function_trace_op
95 aghi %r2,-MCOUNT_INSN_SIZE
96 larl %r4,function_trace_op
102 la %r5,STACK_PTREGS(%r15)
104 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
105 # The j instruction gets runtime patched to a nop instruction.
106 # See ftrace_enable_ftrace_graph_caller.
107 SYM_INNER_LABEL(ftrace_graph_caller, SYM_L_GLOBAL)
108 j .Lftrace_graph_caller_end
109 lmg %r2,%r3,(STACK_PTREGS_GPRS+14*8)(%r15)
110 lg %r4,(STACK_PTREGS_PSW+8)(%r15)
111 brasl %r14,prepare_ftrace_return
112 stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15)
113 .Lftrace_graph_caller_end:
115 lg %r0,(STACK_PTREGS_PSW+8)(%r15)
116 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
117 ltg %r1,STACK_PTREGS_ORIG_GPR2(%r15)
120 lg %r1,STACK_PTREGS_ORIG_GPR2(%r15)
125 0: lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15)
127 SYM_CODE_END(ftrace_common)
129 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
131 SYM_FUNC_START(return_to_handler)
132 stmg %r2,%r5,32(%r15)
134 aghi %r15,-STACK_FRAME_OVERHEAD
135 stg %r1,__SF_BACKCHAIN(%r15)
136 brasl %r14,ftrace_return_to_handler
137 aghi %r15,STACK_FRAME_OVERHEAD
141 SYM_FUNC_END(return_to_handler)