1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_S390_FTRACE_H
3 #define _ASM_S390_FTRACE_H
4
5 #define ARCH_SUPPORTS_FTRACE_OPS 1
6 #define MCOUNT_INSN_SIZE 6
7
8 #ifndef __ASSEMBLY__
9 #include <asm/stacktrace.h>
10
return_address(unsigned int n)11 static __always_inline unsigned long return_address(unsigned int n)
12 {
13 struct stack_frame *sf;
14
15 if (!n)
16 return (unsigned long)__builtin_return_address(0);
17
18 sf = (struct stack_frame *)current_frame_address();
19 do {
20 sf = (struct stack_frame *)sf->back_chain;
21 if (!sf)
22 return 0;
23 } while (--n);
24 return sf->gprs[8];
25 }
26 #define ftrace_return_address(n) return_address(n)
27
28 void ftrace_caller(void);
29
30 extern void *ftrace_func;
31
32 struct dyn_arch_ftrace { };
33
34 #define MCOUNT_ADDR 0
35 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
36
37 #define KPROBE_ON_FTRACE_NOP 0
38 #define KPROBE_ON_FTRACE_CALL 1
39
40 struct module;
41 struct dyn_ftrace;
42 struct ftrace_ops;
43
44 bool ftrace_need_init_nop(void);
45 #define ftrace_need_init_nop ftrace_need_init_nop
46
47 int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
48 #define ftrace_init_nop ftrace_init_nop
49
ftrace_call_adjust(unsigned long addr)50 static inline unsigned long ftrace_call_adjust(unsigned long addr)
51 {
52 return addr;
53 }
54 #define ftrace_get_symaddr(fentry_ip) ((unsigned long)(fentry_ip))
55
56 #include <linux/ftrace_regs.h>
57
arch_ftrace_get_regs(struct ftrace_regs * fregs)58 static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs)
59 {
60 struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
61
62 if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS))
63 return regs;
64 return NULL;
65 }
66
67 static __always_inline void
ftrace_regs_set_instruction_pointer(struct ftrace_regs * fregs,unsigned long ip)68 ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
69 unsigned long ip)
70 {
71 arch_ftrace_regs(fregs)->regs.psw.addr = ip;
72 }
73
74 #undef ftrace_regs_get_frame_pointer
75 static __always_inline unsigned long
ftrace_regs_get_frame_pointer(struct ftrace_regs * fregs)76 ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs)
77 {
78 return ftrace_regs_get_stack_pointer(fregs);
79 }
80
81 static __always_inline unsigned long
ftrace_regs_get_return_address(const struct ftrace_regs * fregs)82 ftrace_regs_get_return_address(const struct ftrace_regs *fregs)
83 {
84 return arch_ftrace_regs(fregs)->regs.gprs[14];
85 }
86
87 #define arch_ftrace_fill_perf_regs(fregs, _regs) do { \
88 (_regs)->psw.mask = 0; \
89 (_regs)->psw.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \
90 (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \
91 } while (0)
92
93 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
94 /*
95 * When an ftrace registered caller is tracing a function that is
96 * also set by a register_ftrace_direct() call, it needs to be
97 * differentiated in the ftrace_caller trampoline. To do this,
98 * place the direct caller in the ORIG_GPR2 part of pt_regs. This
99 * tells the ftrace_caller that there's a direct caller.
100 */
arch_ftrace_set_direct_caller(struct ftrace_regs * fregs,unsigned long addr)101 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr)
102 {
103 struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
104 regs->orig_gpr2 = addr;
105 }
106 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
107
108 /*
109 * Even though the system call numbers are identical for s390/s390x a
110 * different system call table is used for compat tasks. This may lead
111 * to e.g. incorrect or missing trace event sysfs files.
112 * Therefore simply do not trace compat system calls at all.
113 * See kernel/trace/trace_syscalls.c.
114 */
115 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
arch_trace_is_compat_syscall(struct pt_regs * regs)116 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
117 {
118 return is_compat_task();
119 }
120
121 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
arch_syscall_match_sym_name(const char * sym,const char * name)122 static inline bool arch_syscall_match_sym_name(const char *sym,
123 const char *name)
124 {
125 /*
126 * Skip __s390_ and __s390x_ prefix - due to compat wrappers
127 * and aliasing some symbols of 64 bit system call functions
128 * may get the __s390_ prefix instead of the __s390x_ prefix.
129 */
130 return !strcmp(sym + 7, name) || !strcmp(sym + 8, name);
131 }
132
133 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
134 struct ftrace_ops *op, struct ftrace_regs *fregs);
135 #define ftrace_graph_func ftrace_graph_func
136
137 #endif /* __ASSEMBLY__ */
138
139 #ifdef CONFIG_FUNCTION_TRACER
140
141 #define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */
142
143 #ifndef CC_USING_HOTPATCH
144
145 #define FTRACE_GEN_MCOUNT_RECORD(name) \
146 .section __mcount_loc, "a", @progbits; \
147 .quad name; \
148 .previous;
149
150 #else /* !CC_USING_HOTPATCH */
151
152 #define FTRACE_GEN_MCOUNT_RECORD(name)
153
154 #endif /* !CC_USING_HOTPATCH */
155
156 #define FTRACE_GEN_NOP_ASM(name) \
157 FTRACE_GEN_MCOUNT_RECORD(name) \
158 FTRACE_NOP_INSN
159
160 #else /* CONFIG_FUNCTION_TRACER */
161
162 #define FTRACE_GEN_NOP_ASM(name)
163
164 #endif /* CONFIG_FUNCTION_TRACER */
165
166 #endif /* _ASM_S390_FTRACE_H */
167