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