1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Common header file for probe-based Dynamic events. 4 * 5 * This code was copied from kernel/trace/trace_kprobe.h written by 6 * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> 7 * 8 * Updates to make this generic: 9 * Copyright (C) IBM Corporation, 2010-2011 10 * Author: Srikar Dronamraju 11 */ 12 13 #include <linux/seq_file.h> 14 #include <linux/slab.h> 15 #include <linux/smp.h> 16 #include <linux/tracefs.h> 17 #include <linux/types.h> 18 #include <linux/string.h> 19 #include <linux/ptrace.h> 20 #include <linux/perf_event.h> 21 #include <linux/kprobes.h> 22 #include <linux/stringify.h> 23 #include <linux/limits.h> 24 #include <linux/uaccess.h> 25 #include <linux/bitops.h> 26 #include <asm/bitsperlong.h> 27 28 #include "trace.h" 29 #include "trace_output.h" 30 31 #define MAX_TRACE_ARGS 128 32 #define MAX_ARGSTR_LEN 63 33 #define MAX_ARRAY_LEN 64 34 #define MAX_ARG_NAME_LEN 32 35 #define MAX_STRING_SIZE PATH_MAX 36 37 /* Reserved field names */ 38 #define FIELD_STRING_IP "__probe_ip" 39 #define FIELD_STRING_RETIP "__probe_ret_ip" 40 #define FIELD_STRING_FUNC "__probe_func" 41 #define FIELD_STRING_TYPE "__probe_type" 42 43 #undef DEFINE_FIELD 44 #define DEFINE_FIELD(type, item, name, is_signed) \ 45 do { \ 46 ret = trace_define_field(event_call, #type, name, \ 47 offsetof(typeof(field), item), \ 48 sizeof(field.item), is_signed, \ 49 FILTER_OTHER); \ 50 if (ret) \ 51 return ret; \ 52 } while (0) 53 54 55 /* Flags for trace_probe */ 56 #define TP_FLAG_TRACE 1 57 #define TP_FLAG_PROFILE 2 58 59 /* data_loc: data location, compatible with u32 */ 60 #define make_data_loc(len, offs) \ 61 (((u32)(len) << 16) | ((u32)(offs) & 0xffff)) 62 #define get_loc_len(dl) ((u32)(dl) >> 16) 63 #define get_loc_offs(dl) ((u32)(dl) & 0xffff) 64 65 static nokprobe_inline void *get_loc_data(u32 *dl, void *ent) 66 { 67 return (u8 *)ent + get_loc_offs(*dl); 68 } 69 70 static nokprobe_inline u32 update_data_loc(u32 loc, int consumed) 71 { 72 u32 maxlen = get_loc_len(loc); 73 u32 offset = get_loc_offs(loc); 74 75 return make_data_loc(maxlen - consumed, offset + consumed); 76 } 77 78 /* Printing function type */ 79 typedef int (*print_type_func_t)(struct trace_seq *, void *, void *); 80 81 enum fetch_op { 82 FETCH_OP_NOP = 0, 83 // Stage 1 (load) ops 84 FETCH_OP_REG, /* Register : .param = offset */ 85 FETCH_OP_STACK, /* Stack : .param = index */ 86 FETCH_OP_STACKP, /* Stack pointer */ 87 FETCH_OP_RETVAL, /* Return value */ 88 FETCH_OP_IMM, /* Immediate : .immediate */ 89 FETCH_OP_COMM, /* Current comm */ 90 FETCH_OP_ARG, /* Function argument : .param */ 91 FETCH_OP_FOFFS, /* File offset: .immediate */ 92 FETCH_OP_DATA, /* Allocated data: .data */ 93 // Stage 2 (dereference) op 94 FETCH_OP_DEREF, /* Dereference: .offset */ 95 FETCH_OP_UDEREF, /* User-space Dereference: .offset */ 96 // Stage 3 (store) ops 97 FETCH_OP_ST_RAW, /* Raw: .size */ 98 FETCH_OP_ST_MEM, /* Mem: .offset, .size */ 99 FETCH_OP_ST_UMEM, /* Mem: .offset, .size */ 100 FETCH_OP_ST_STRING, /* String: .offset, .size */ 101 FETCH_OP_ST_USTRING, /* User String: .offset, .size */ 102 // Stage 4 (modify) op 103 FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */ 104 // Stage 5 (loop) op 105 FETCH_OP_LP_ARRAY, /* Array: .param = loop count */ 106 FETCH_OP_TP_ARG, /* Trace Point argument */ 107 FETCH_OP_END, 108 FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */ 109 }; 110 111 struct fetch_insn { 112 enum fetch_op op; 113 union { 114 unsigned int param; 115 struct { 116 unsigned int size; 117 int offset; 118 }; 119 struct { 120 unsigned char basesize; 121 unsigned char lshift; 122 unsigned char rshift; 123 }; 124 unsigned long immediate; 125 void *data; 126 }; 127 }; 128 129 /* fetch + deref*N + store + mod + end <= 16, this allows N=12, enough */ 130 #define FETCH_INSN_MAX 16 131 #define FETCH_TOKEN_COMM (-ECOMM) 132 133 /* Fetch type information table */ 134 struct fetch_type { 135 const char *name; /* Name of type */ 136 size_t size; /* Byte size of type */ 137 int is_signed; /* Signed flag */ 138 print_type_func_t print; /* Print functions */ 139 const char *fmt; /* Format string */ 140 const char *fmttype; /* Name in format file */ 141 }; 142 143 /* For defining macros, define string/string_size types */ 144 typedef u32 string; 145 typedef u32 string_size; 146 147 #define PRINT_TYPE_FUNC_NAME(type) print_type_##type 148 #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type 149 150 /* Printing in basic type function template */ 151 #define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ 152 int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\ 153 extern const char PRINT_TYPE_FMT_NAME(type)[] 154 155 DECLARE_BASIC_PRINT_TYPE_FUNC(u8); 156 DECLARE_BASIC_PRINT_TYPE_FUNC(u16); 157 DECLARE_BASIC_PRINT_TYPE_FUNC(u32); 158 DECLARE_BASIC_PRINT_TYPE_FUNC(u64); 159 DECLARE_BASIC_PRINT_TYPE_FUNC(s8); 160 DECLARE_BASIC_PRINT_TYPE_FUNC(s16); 161 DECLARE_BASIC_PRINT_TYPE_FUNC(s32); 162 DECLARE_BASIC_PRINT_TYPE_FUNC(s64); 163 DECLARE_BASIC_PRINT_TYPE_FUNC(x8); 164 DECLARE_BASIC_PRINT_TYPE_FUNC(x16); 165 DECLARE_BASIC_PRINT_TYPE_FUNC(x32); 166 DECLARE_BASIC_PRINT_TYPE_FUNC(x64); 167 168 DECLARE_BASIC_PRINT_TYPE_FUNC(string); 169 DECLARE_BASIC_PRINT_TYPE_FUNC(symbol); 170 171 /* Default (unsigned long) fetch type */ 172 #define __DEFAULT_FETCH_TYPE(t) x##t 173 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) 174 #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) 175 #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) 176 177 #define __ADDR_FETCH_TYPE(t) u##t 178 #define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t) 179 #define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG) 180 181 #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ 182 {.name = _name, \ 183 .size = _size, \ 184 .is_signed = sign, \ 185 .print = PRINT_TYPE_FUNC_NAME(ptype), \ 186 .fmt = PRINT_TYPE_FMT_NAME(ptype), \ 187 .fmttype = _fmttype, \ 188 } 189 #define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ 190 __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype) 191 #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ 192 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype) 193 194 /* If ptype is an alias of atype, use this macro (show atype in format) */ 195 #define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \ 196 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype) 197 198 #define ASSIGN_FETCH_TYPE_END {} 199 #define MAX_ARRAY_LEN 64 200 201 #ifdef CONFIG_KPROBE_EVENTS 202 bool trace_kprobe_on_func_entry(struct trace_event_call *call); 203 bool trace_kprobe_error_injectable(struct trace_event_call *call); 204 #else 205 static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call) 206 { 207 return false; 208 } 209 210 static inline bool trace_kprobe_error_injectable(struct trace_event_call *call) 211 { 212 return false; 213 } 214 #endif /* CONFIG_KPROBE_EVENTS */ 215 216 struct probe_arg { 217 struct fetch_insn *code; 218 bool dynamic;/* Dynamic array (string) is used */ 219 unsigned int offset; /* Offset from argument entry */ 220 unsigned int count; /* Array count */ 221 const char *name; /* Name of this argument */ 222 const char *comm; /* Command of this argument */ 223 char *fmt; /* Format string if needed */ 224 const struct fetch_type *type; /* Type of this argument */ 225 }; 226 227 struct trace_uprobe_filter { 228 rwlock_t rwlock; 229 int nr_systemwide; 230 struct list_head perf_events; 231 }; 232 233 /* Event call and class holder */ 234 struct trace_probe_event { 235 unsigned int flags; /* For TP_FLAG_* */ 236 struct trace_event_class class; 237 struct trace_event_call call; 238 struct list_head files; 239 struct list_head probes; 240 struct trace_uprobe_filter filter[]; 241 }; 242 243 struct trace_probe { 244 struct list_head list; 245 struct trace_probe_event *event; 246 ssize_t size; /* trace entry size */ 247 unsigned int nr_args; 248 struct probe_arg args[]; 249 }; 250 251 struct event_file_link { 252 struct trace_event_file *file; 253 struct list_head list; 254 }; 255 256 static inline bool trace_probe_test_flag(struct trace_probe *tp, 257 unsigned int flag) 258 { 259 return !!(tp->event->flags & flag); 260 } 261 262 static inline void trace_probe_set_flag(struct trace_probe *tp, 263 unsigned int flag) 264 { 265 tp->event->flags |= flag; 266 } 267 268 static inline void trace_probe_clear_flag(struct trace_probe *tp, 269 unsigned int flag) 270 { 271 tp->event->flags &= ~flag; 272 } 273 274 static inline bool trace_probe_is_enabled(struct trace_probe *tp) 275 { 276 return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE); 277 } 278 279 static inline const char *trace_probe_name(struct trace_probe *tp) 280 { 281 return trace_event_name(&tp->event->call); 282 } 283 284 static inline const char *trace_probe_group_name(struct trace_probe *tp) 285 { 286 return tp->event->call.class->system; 287 } 288 289 static inline struct trace_event_call * 290 trace_probe_event_call(struct trace_probe *tp) 291 { 292 return &tp->event->call; 293 } 294 295 static inline struct trace_probe_event * 296 trace_probe_event_from_call(struct trace_event_call *event_call) 297 { 298 return container_of(event_call, struct trace_probe_event, call); 299 } 300 301 static inline struct trace_probe * 302 trace_probe_primary_from_call(struct trace_event_call *call) 303 { 304 struct trace_probe_event *tpe = trace_probe_event_from_call(call); 305 306 return list_first_entry(&tpe->probes, struct trace_probe, list); 307 } 308 309 static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp) 310 { 311 return &tp->event->probes; 312 } 313 314 static inline bool trace_probe_has_sibling(struct trace_probe *tp) 315 { 316 struct list_head *list = trace_probe_probe_list(tp); 317 318 return !list_empty(list) && !list_is_singular(list); 319 } 320 321 static inline int trace_probe_unregister_event_call(struct trace_probe *tp) 322 { 323 /* tp->event is unregistered in trace_remove_event_call() */ 324 return trace_remove_event_call(&tp->event->call); 325 } 326 327 static inline bool trace_probe_has_single_file(struct trace_probe *tp) 328 { 329 return !!list_is_singular(&tp->event->files); 330 } 331 332 int trace_probe_init(struct trace_probe *tp, const char *event, 333 const char *group, bool alloc_filter); 334 void trace_probe_cleanup(struct trace_probe *tp); 335 int trace_probe_append(struct trace_probe *tp, struct trace_probe *to); 336 void trace_probe_unlink(struct trace_probe *tp); 337 int trace_probe_register_event_call(struct trace_probe *tp); 338 int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file); 339 int trace_probe_remove_file(struct trace_probe *tp, 340 struct trace_event_file *file); 341 struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp, 342 struct trace_event_file *file); 343 int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b); 344 bool trace_probe_match_command_args(struct trace_probe *tp, 345 int argc, const char **argv); 346 int trace_probe_create(const char *raw_command, int (*createfn)(int, const char **)); 347 348 #define trace_probe_for_each_link(pos, tp) \ 349 list_for_each_entry(pos, &(tp)->event->files, list) 350 #define trace_probe_for_each_link_rcu(pos, tp) \ 351 list_for_each_entry_rcu(pos, &(tp)->event->files, list) 352 353 #define TPARG_FL_RETURN BIT(0) 354 #define TPARG_FL_KERNEL BIT(1) 355 #define TPARG_FL_FENTRY BIT(2) 356 #define TPARG_FL_TPOINT BIT(3) 357 #define TPARG_FL_MASK GENMASK(3, 0) 358 359 extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, 360 const char *argv, unsigned int flags); 361 362 extern int traceprobe_update_arg(struct probe_arg *arg); 363 extern void traceprobe_free_probe_arg(struct probe_arg *arg); 364 365 extern int traceprobe_split_symbol_offset(char *symbol, long *offset); 366 int traceprobe_parse_event_name(const char **pevent, const char **pgroup, 367 char *buf, int offset); 368 369 enum probe_print_type { 370 PROBE_PRINT_NORMAL, 371 PROBE_PRINT_RETURN, 372 PROBE_PRINT_EVENT, 373 }; 374 375 extern int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype); 376 377 #ifdef CONFIG_PERF_EVENTS 378 extern struct trace_event_call * 379 create_local_trace_kprobe(char *func, void *addr, unsigned long offs, 380 bool is_return); 381 extern void destroy_local_trace_kprobe(struct trace_event_call *event_call); 382 383 extern struct trace_event_call * 384 create_local_trace_uprobe(char *name, unsigned long offs, 385 unsigned long ref_ctr_offset, bool is_return); 386 extern void destroy_local_trace_uprobe(struct trace_event_call *event_call); 387 #endif 388 extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, 389 size_t offset, struct trace_probe *tp); 390 391 #undef ERRORS 392 #define ERRORS \ 393 C(FILE_NOT_FOUND, "Failed to find the given file"), \ 394 C(NO_REGULAR_FILE, "Not a regular file"), \ 395 C(BAD_REFCNT, "Invalid reference counter offset"), \ 396 C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \ 397 C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \ 398 C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \ 399 C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \ 400 C(BAD_MAXACT, "Invalid maxactive number"), \ 401 C(MAXACT_TOO_BIG, "Maxactive is too big"), \ 402 C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \ 403 C(BAD_RETPROBE, "Retprobe address must be an function entry"), \ 404 C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \ 405 C(NO_GROUP_NAME, "Group name is not specified"), \ 406 C(GROUP_TOO_LONG, "Group name is too long"), \ 407 C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \ 408 C(NO_EVENT_NAME, "Event name is not specified"), \ 409 C(EVENT_TOO_LONG, "Event name is too long"), \ 410 C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \ 411 C(EVENT_EXIST, "Given group/event name is already used by another event"), \ 412 C(RETVAL_ON_PROBE, "$retval is not available on probe"), \ 413 C(BAD_STACK_NUM, "Invalid stack number"), \ 414 C(BAD_ARG_NUM, "Invalid argument number"), \ 415 C(BAD_VAR, "Invalid $-valiable specified"), \ 416 C(BAD_REG_NAME, "Invalid register name"), \ 417 C(BAD_MEM_ADDR, "Invalid memory address"), \ 418 C(BAD_IMM, "Invalid immediate value"), \ 419 C(IMMSTR_NO_CLOSE, "String is not closed with '\"'"), \ 420 C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \ 421 C(BAD_FILE_OFFS, "Invalid file offset value"), \ 422 C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \ 423 C(TOO_MANY_OPS, "Dereference is too much nested"), \ 424 C(DEREF_NEED_BRACE, "Dereference needs a brace"), \ 425 C(BAD_DEREF_OFFS, "Invalid dereference offset"), \ 426 C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \ 427 C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \ 428 C(BAD_FETCH_ARG, "Invalid fetch argument"), \ 429 C(ARRAY_NO_CLOSE, "Array is not closed"), \ 430 C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \ 431 C(BAD_ARRAY_NUM, "Invalid array size"), \ 432 C(ARRAY_TOO_BIG, "Array number is too big"), \ 433 C(BAD_TYPE, "Unknown type is specified"), \ 434 C(BAD_STRING, "String accepts only memory argument"), \ 435 C(BAD_BITFIELD, "Invalid bitfield"), \ 436 C(ARG_NAME_TOO_LONG, "Argument name is too long"), \ 437 C(NO_ARG_NAME, "Argument name is not specified"), \ 438 C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \ 439 C(USED_ARG_NAME, "This argument name is already used"), \ 440 C(ARG_TOO_LONG, "Argument expression is too long"), \ 441 C(NO_ARG_BODY, "No argument expression"), \ 442 C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\ 443 C(FAIL_REG_PROBE, "Failed to register probe event"),\ 444 C(DIFF_PROBE_TYPE, "Probe type is different from existing probe"),\ 445 C(DIFF_ARG_TYPE, "Argument type or name is different from existing probe"),\ 446 C(SAME_PROBE, "There is already the exact same probe event"), 447 448 #undef C 449 #define C(a, b) TP_ERR_##a 450 451 /* Define TP_ERR_ */ 452 enum { ERRORS }; 453 454 /* Error text is defined in trace_probe.c */ 455 456 struct trace_probe_log { 457 const char *subsystem; 458 const char **argv; 459 int argc; 460 int index; 461 }; 462 463 void trace_probe_log_init(const char *subsystem, int argc, const char **argv); 464 void trace_probe_log_set_index(int index); 465 void trace_probe_log_clear(void); 466 void __trace_probe_log_err(int offset, int err); 467 468 #define trace_probe_log_err(offs, err) \ 469 __trace_probe_log_err(offs, TP_ERR_##err) 470