1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_FTRACE_H 3 #define _ASM_X86_FTRACE_H 4 5 #include <asm/ptrace.h> 6 7 #ifdef CONFIG_FUNCTION_TRACER 8 #ifndef CC_USING_FENTRY 9 # error Compiler does not support fentry? 10 #endif 11 # define MCOUNT_ADDR ((unsigned long)(__fentry__)) 12 #define MCOUNT_INSN_SIZE 5 /* sizeof mcount call */ 13 14 /* Ignore unused weak functions which will have non zero offsets */ 15 #ifdef CONFIG_HAVE_FENTRY 16 # include <asm/ibt.h> 17 /* Add offset for endbr64 if IBT enabled */ 18 # define FTRACE_MCOUNT_MAX_OFFSET ENDBR_INSN_SIZE 19 #endif 20 21 #ifdef CONFIG_DYNAMIC_FTRACE 22 #define ARCH_SUPPORTS_FTRACE_OPS 1 23 #endif 24 25 #ifndef __ASSEMBLY__ 26 extern void __fentry__(void); 27 28 static inline unsigned long ftrace_call_adjust(unsigned long addr) 29 { 30 /* 31 * addr is the address of the mcount call instruction. 32 * recordmcount does the necessary offset calculation. 33 */ 34 return addr; 35 } 36 37 static inline unsigned long arch_ftrace_get_symaddr(unsigned long fentry_ip) 38 { 39 #ifdef CONFIG_X86_KERNEL_IBT 40 u32 instr; 41 42 /* We want to be extra safe in case entry ip is on the page edge, 43 * but otherwise we need to avoid get_kernel_nofault()'s overhead. 44 */ 45 if ((fentry_ip & ~PAGE_MASK) < ENDBR_INSN_SIZE) { 46 if (get_kernel_nofault(instr, (u32 *)(fentry_ip - ENDBR_INSN_SIZE))) 47 return fentry_ip; 48 } else { 49 instr = *(u32 *)(fentry_ip - ENDBR_INSN_SIZE); 50 } 51 if (is_endbr(instr)) 52 fentry_ip -= ENDBR_INSN_SIZE; 53 #endif 54 return fentry_ip; 55 } 56 #define ftrace_get_symaddr(fentry_ip) arch_ftrace_get_symaddr(fentry_ip) 57 58 #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS 59 60 #include <linux/ftrace_regs.h> 61 62 static __always_inline struct pt_regs * 63 arch_ftrace_get_regs(struct ftrace_regs *fregs) 64 { 65 /* Only when FL_SAVE_REGS is set, cs will be non zero */ 66 if (!arch_ftrace_regs(fregs)->regs.cs) 67 return NULL; 68 return &arch_ftrace_regs(fregs)->regs; 69 } 70 71 #define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ 72 (_regs)->ip = arch_ftrace_regs(fregs)->regs.ip; \ 73 (_regs)->sp = arch_ftrace_regs(fregs)->regs.sp; \ 74 (_regs)->cs = __KERNEL_CS; \ 75 (_regs)->flags = 0; \ 76 } while (0) 77 78 #define ftrace_regs_set_instruction_pointer(fregs, _ip) \ 79 do { arch_ftrace_regs(fregs)->regs.ip = (_ip); } while (0) 80 81 82 static __always_inline unsigned long 83 ftrace_regs_get_return_address(struct ftrace_regs *fregs) 84 { 85 return *(unsigned long *)ftrace_regs_get_stack_pointer(fregs); 86 } 87 88 struct ftrace_ops; 89 #define ftrace_graph_func ftrace_graph_func 90 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, 91 struct ftrace_ops *op, struct ftrace_regs *fregs); 92 #else 93 #define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR 94 #endif 95 96 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 97 /* 98 * When a ftrace registered caller is tracing a function that is 99 * also set by a register_ftrace_direct() call, it needs to be 100 * differentiated in the ftrace_caller trampoline. To do this, we 101 * place the direct caller in the ORIG_AX part of pt_regs. This 102 * tells the ftrace_caller that there's a direct caller. 103 */ 104 static inline void 105 __arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) 106 { 107 /* Emulate a call */ 108 regs->orig_ax = addr; 109 } 110 #define arch_ftrace_set_direct_caller(fregs, addr) \ 111 __arch_ftrace_set_direct_caller(&arch_ftrace_regs(fregs)->regs, addr) 112 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ 113 114 #ifdef CONFIG_DYNAMIC_FTRACE 115 116 struct dyn_arch_ftrace { 117 /* No extra data needed for x86 */ 118 }; 119 120 #endif /* CONFIG_DYNAMIC_FTRACE */ 121 #endif /* __ASSEMBLY__ */ 122 #endif /* CONFIG_FUNCTION_TRACER */ 123 124 125 #ifndef __ASSEMBLY__ 126 127 void prepare_ftrace_return(unsigned long ip, unsigned long *parent, 128 unsigned long frame_pointer); 129 130 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 131 extern void set_ftrace_ops_ro(void); 132 #else 133 static inline void set_ftrace_ops_ro(void) { } 134 #endif 135 136 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME 137 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) 138 { 139 /* 140 * Compare the symbol name with the system call name. Skip the 141 * "__x64_sys", "__ia32_sys", "__do_sys" or simple "sys" prefix. 142 */ 143 return !strcmp(sym + 3, name + 3) || 144 (!strncmp(sym, "__x64_", 6) && !strcmp(sym + 9, name + 3)) || 145 (!strncmp(sym, "__ia32_", 7) && !strcmp(sym + 10, name + 3)) || 146 (!strncmp(sym, "__do_sys", 8) && !strcmp(sym + 8, name + 3)); 147 } 148 149 #ifndef COMPILE_OFFSETS 150 151 #if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION) 152 #include <linux/compat.h> 153 154 /* 155 * Because ia32 syscalls do not map to x86_64 syscall numbers 156 * this screws up the trace output when tracing a ia32 task. 157 * Instead of reporting bogus syscalls, just do not trace them. 158 * 159 * If the user really wants these, then they should use the 160 * raw syscall tracepoints with filtering. 161 */ 162 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1 163 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) 164 { 165 return in_32bit_syscall(); 166 } 167 #endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */ 168 #endif /* !COMPILE_OFFSETS */ 169 #endif /* !__ASSEMBLY__ */ 170 171 #endif /* _ASM_X86_FTRACE_H */ 172