1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright IBM Corp. 2008, 2009
7 #include <linux/linkage.h>
8 #include <asm/asm-offsets.h>
9 #include <asm/ftrace.h>
10 #include <asm/nospec-insn.h>
11 #include <asm/ptrace.h>
13 #define STACK_FRAME_SIZE_PTREGS (STACK_FRAME_OVERHEAD + __PT_SIZE)
14 #define STACK_PTREGS (STACK_FRAME_OVERHEAD)
15 #define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
16 #define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
18 #define STACK_FRAME_SIZE_FREGS (STACK_FRAME_OVERHEAD + __FTRACE_REGS_SIZE)
19 #define STACK_FREGS (STACK_FRAME_OVERHEAD)
20 #define STACK_FREGS_PTREGS (STACK_FRAME_OVERHEAD + __FTRACE_REGS_PT_REGS)
21 #define STACK_FREGS_PTREGS_GPRS (STACK_FREGS_PTREGS + __PT_GPRS)
22 #define STACK_FREGS_PTREGS_PSW (STACK_FREGS_PTREGS + __PT_PSW)
23 #define STACK_FREGS_PTREGS_ORIG_GPR2 (STACK_FREGS_PTREGS + __PT_ORIG_GPR2)
24 #define STACK_FREGS_PTREGS_FLAGS (STACK_FREGS_PTREGS + __PT_FLAGS)
26 /* packed stack: allocate just enough for r14, r15 and backchain */
27 #define TRACED_FUNC_FRAME_SIZE 24
29 #ifdef CONFIG_FUNCTION_TRACER
34 .section .kprobes.text, "ax"
36 SYM_FUNC_START(ftrace_stub)
38 SYM_FUNC_END(ftrace_stub)
40 SYM_CODE_START(ftrace_stub_direct_tramp)
43 SYM_CODE_END(ftrace_stub_direct_tramp)
45 .macro ftrace_regs_entry, allregs=0
46 stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller
50 # don't put any instructions clobbering CC before this point
52 risbg %r14,%r1,0,31,32
56 # allocate stack frame for ftrace_caller to contain traced function
57 aghi %r15,-TRACED_FUNC_FRAME_SIZE
58 stg %r1,__SF_BACKCHAIN(%r15)
59 stg %r0,(__SF_GPRS+8*8)(%r15)
60 stg %r15,(__SF_GPRS+9*8)(%r15)
61 # allocate ftrace_regs and stack frame for ftrace_trace_function
62 aghi %r15,-STACK_FRAME_SIZE_FREGS
63 stg %r1,(STACK_FREGS_PTREGS_GPRS+15*8)(%r15)
64 xc STACK_FREGS_PTREGS_ORIG_GPR2(8,%r15),STACK_FREGS_PTREGS_ORIG_GPR2(%r15)
67 stg %r14,(STACK_FREGS_PTREGS_PSW)(%r15)
68 mvghi STACK_FREGS_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS
70 xc STACK_FREGS_PTREGS_FLAGS(8,%r15),STACK_FREGS_PTREGS_FLAGS(%r15)
73 lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address
74 aghi %r1,-TRACED_FUNC_FRAME_SIZE
75 stg %r1,__SF_BACKCHAIN(%r15)
76 stg %r0,(STACK_FREGS_PTREGS_PSW+8)(%r15)
77 stmg %r2,%r14,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15)
80 SYM_CODE_START(ftrace_regs_caller)
83 SYM_CODE_END(ftrace_regs_caller)
85 SYM_CODE_START(ftrace_caller)
88 SYM_CODE_END(ftrace_caller)
90 SYM_CODE_START(ftrace_common)
91 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
92 aghik %r2,%r0,-MCOUNT_INSN_SIZE
93 lgrl %r4,function_trace_op
97 aghi %r2,-MCOUNT_INSN_SIZE
98 larl %r4,function_trace_op
104 la %r5,STACK_FREGS(%r15)
106 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
107 # The j instruction gets runtime patched to a nop instruction.
108 # See ftrace_enable_ftrace_graph_caller.
109 SYM_INNER_LABEL(ftrace_graph_caller, SYM_L_GLOBAL)
110 j .Lftrace_graph_caller_end
111 lmg %r2,%r3,(STACK_FREGS_PTREGS_GPRS+14*8)(%r15)
112 lg %r4,(STACK_FREGS_PTREGS_PSW+8)(%r15)
113 brasl %r14,prepare_ftrace_return
114 stg %r2,(STACK_FREGS_PTREGS_GPRS+14*8)(%r15)
115 .Lftrace_graph_caller_end:
117 lg %r0,(STACK_FREGS_PTREGS_PSW+8)(%r15)
118 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
119 ltg %r1,STACK_FREGS_PTREGS_ORIG_GPR2(%r15)
122 lg %r1,STACK_FREGS_PTREGS_ORIG_GPR2(%r15)
127 0: lmg %r2,%r15,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15)
129 SYM_CODE_END(ftrace_common)
131 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
133 SYM_FUNC_START(return_to_handler)
134 stmg %r2,%r5,32(%r15)
136 aghi %r15,-(STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE)
137 stg %r1,__SF_BACKCHAIN(%r15)
138 la %r3,STACK_FRAME_OVERHEAD(%r15)
139 stg %r1,__FGRAPH_RET_FP(%r3)
140 stg %r2,__FGRAPH_RET_GPR2(%r3)
142 brasl %r14,ftrace_return_to_handler
143 aghi %r15,STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE
147 SYM_FUNC_END(return_to_handler)
150 #endif /* CONFIG_FUNCTION_TRACER */
152 SYM_CODE_START(ftrace_shared_hotpatch_trampoline_br)
155 SYM_INNER_LABEL(ftrace_shared_hotpatch_trampoline_br_end, SYM_L_GLOBAL)
156 SYM_CODE_END(ftrace_shared_hotpatch_trampoline_br)
158 #ifdef CONFIG_EXPOLINE
159 SYM_CODE_START(ftrace_shared_hotpatch_trampoline_exrl)
164 SYM_INNER_LABEL(ftrace_shared_hotpatch_trampoline_exrl_end, SYM_L_GLOBAL)
165 SYM_CODE_END(ftrace_shared_hotpatch_trampoline_exrl)
166 #endif /* CONFIG_EXPOLINE */
168 #ifdef CONFIG_RETHOOK
170 SYM_CODE_START(arch_rethook_trampoline)
171 stg %r14,(__SF_GPRS+8*8)(%r15)
172 lay %r15,-STACK_FRAME_SIZE_PTREGS(%r15)
173 stmg %r0,%r14,STACK_PTREGS_GPRS(%r15)
175 # store original stack pointer in backchain and pt_regs
176 lay %r7,STACK_FRAME_SIZE_PTREGS(%r15)
177 stg %r7,__SF_BACKCHAIN(%r15)
178 stg %r7,STACK_PTREGS_GPRS+(15*8)(%r15)
182 risbg %r3,%r2,0,31,32
183 stg %r3,STACK_PTREGS_PSW(%r15)
184 larl %r1,arch_rethook_trampoline
185 stg %r1,STACK_PTREGS_PSW+8(%r15)
187 lay %r2,STACK_PTREGS(%r15)
188 brasl %r14,arch_rethook_trampoline_callback
190 mvc __SF_EMPTY(16,%r7),STACK_PTREGS_PSW(%r15)
191 lmg %r0,%r15,STACK_PTREGS_GPRS(%r15)
192 lpswe __SF_EMPTY(%r15)
193 SYM_CODE_END(arch_rethook_trampoline)
195 #endif /* CONFIG_RETHOOK */