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 10 unsigned long return_address(unsigned int n); 11 #define ftrace_return_address(n) return_address(n) 12 13 void ftrace_caller(void); 14 15 extern void *ftrace_func; 16 17 struct dyn_arch_ftrace { }; 18 19 #define MCOUNT_ADDR 0 20 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 21 22 #define KPROBE_ON_FTRACE_NOP 0 23 #define KPROBE_ON_FTRACE_CALL 1 24 25 struct module; 26 struct dyn_ftrace; 27 28 bool ftrace_need_init_nop(void); 29 #define ftrace_need_init_nop ftrace_need_init_nop 30 31 int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); 32 #define ftrace_init_nop ftrace_init_nop 33 34 static inline unsigned long ftrace_call_adjust(unsigned long addr) 35 { 36 return addr; 37 } 38 39 struct ftrace_regs { 40 struct pt_regs regs; 41 }; 42 43 static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) 44 { 45 struct pt_regs *regs = &fregs->regs; 46 47 if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS)) 48 return regs; 49 return NULL; 50 } 51 52 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 53 struct fgraph_ret_regs { 54 unsigned long gpr2; 55 unsigned long fp; 56 }; 57 58 static __always_inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) 59 { 60 return ret_regs->gpr2; 61 } 62 63 static __always_inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) 64 { 65 return ret_regs->fp; 66 } 67 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 68 69 static __always_inline unsigned long 70 ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs) 71 { 72 return fregs->regs.psw.addr; 73 } 74 75 static __always_inline void 76 ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, 77 unsigned long ip) 78 { 79 fregs->regs.psw.addr = ip; 80 } 81 82 #define ftrace_regs_get_argument(fregs, n) \ 83 regs_get_kernel_argument(&(fregs)->regs, n) 84 #define ftrace_regs_get_stack_pointer(fregs) \ 85 kernel_stack_pointer(&(fregs)->regs) 86 #define ftrace_regs_return_value(fregs) \ 87 regs_return_value(&(fregs)->regs) 88 #define ftrace_regs_set_return_value(fregs, ret) \ 89 regs_set_return_value(&(fregs)->regs, ret) 90 #define ftrace_override_function_with_return(fregs) \ 91 override_function_with_return(&(fregs)->regs) 92 #define ftrace_regs_query_register_offset(name) \ 93 regs_query_register_offset(name) 94 95 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 96 /* 97 * When an ftrace registered caller is tracing a function that is 98 * also set by a register_ftrace_direct() call, it needs to be 99 * differentiated in the ftrace_caller trampoline. To do this, 100 * place the direct caller in the ORIG_GPR2 part of pt_regs. This 101 * tells the ftrace_caller that there's a direct caller. 102 */ 103 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr) 104 { 105 struct pt_regs *regs = &fregs->regs; 106 regs->orig_gpr2 = addr; 107 } 108 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ 109 110 /* 111 * Even though the system call numbers are identical for s390/s390x a 112 * different system call table is used for compat tasks. This may lead 113 * to e.g. incorrect or missing trace event sysfs files. 114 * Therefore simply do not trace compat system calls at all. 115 * See kernel/trace/trace_syscalls.c. 116 */ 117 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 118 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) 119 { 120 return is_compat_task(); 121 } 122 123 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME 124 static inline bool arch_syscall_match_sym_name(const char *sym, 125 const char *name) 126 { 127 /* 128 * Skip __s390_ and __s390x_ prefix - due to compat wrappers 129 * and aliasing some symbols of 64 bit system call functions 130 * may get the __s390_ prefix instead of the __s390x_ prefix. 131 */ 132 return !strcmp(sym + 7, name) || !strcmp(sym + 8, name); 133 } 134 135 #endif /* __ASSEMBLY__ */ 136 137 #ifdef CONFIG_FUNCTION_TRACER 138 139 #define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */ 140 141 #ifndef CC_USING_HOTPATCH 142 143 #define FTRACE_GEN_MCOUNT_RECORD(name) \ 144 .section __mcount_loc, "a", @progbits; \ 145 .quad name; \ 146 .previous; 147 148 #else /* !CC_USING_HOTPATCH */ 149 150 #define FTRACE_GEN_MCOUNT_RECORD(name) 151 152 #endif /* !CC_USING_HOTPATCH */ 153 154 #define FTRACE_GEN_NOP_ASM(name) \ 155 FTRACE_GEN_MCOUNT_RECORD(name) \ 156 FTRACE_NOP_INSN 157 158 #else /* CONFIG_FUNCTION_TRACER */ 159 160 #define FTRACE_GEN_NOP_ASM(name) 161 162 #endif /* CONFIG_FUNCTION_TRACER */ 163 164 #endif /* _ASM_S390_FTRACE_H */ 165