1 // SPDX-License-Identifier: GPL-2.0
3 * Common header file for probe-based Dynamic events.
5 * This code was copied from kernel/trace/trace_kprobe.h written by
6 * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
8 * Updates to make this generic:
9 * Copyright (C) IBM Corporation, 2010-2011
10 * Author: Srikar Dronamraju
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/ctype.h>
20 #include <linux/ptrace.h>
21 #include <linux/perf_event.h>
22 #include <linux/kprobes.h>
23 #include <linux/stringify.h>
24 #include <linux/limits.h>
25 #include <linux/uaccess.h>
26 #include <linux/bitops.h>
27 #include <asm/bitsperlong.h>
30 #include "trace_output.h"
32 #define MAX_TRACE_ARGS 128
33 #define MAX_ARGSTR_LEN 63
34 #define MAX_ARRAY_LEN 64
35 #define MAX_ARG_NAME_LEN 32
36 #define MAX_STRING_SIZE PATH_MAX
38 /* Reserved field names */
39 #define FIELD_STRING_IP "__probe_ip"
40 #define FIELD_STRING_RETIP "__probe_ret_ip"
41 #define FIELD_STRING_FUNC "__probe_func"
44 #define DEFINE_FIELD(type, item, name, is_signed) \
46 ret = trace_define_field(event_call, #type, name, \
47 offsetof(typeof(field), item), \
48 sizeof(field.item), is_signed, \
55 /* Flags for trace_probe */
56 #define TP_FLAG_TRACE 1
57 #define TP_FLAG_PROFILE 2
58 #define TP_FLAG_REGISTERED 4
60 /* data_loc: data location, compatible with u32 */
61 #define make_data_loc(len, offs) \
62 (((u32)(len) << 16) | ((u32)(offs) & 0xffff))
63 #define get_loc_len(dl) ((u32)(dl) >> 16)
64 #define get_loc_offs(dl) ((u32)(dl) & 0xffff)
66 static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
68 return (u8 *)ent + get_loc_offs(*dl);
71 static nokprobe_inline u32 update_data_loc(u32 loc, int consumed)
73 u32 maxlen = get_loc_len(loc);
74 u32 offset = get_loc_offs(loc);
76 return make_data_loc(maxlen - consumed, offset + consumed);
79 /* Printing function type */
80 typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
85 FETCH_OP_REG, /* Register : .param = offset */
86 FETCH_OP_STACK, /* Stack : .param = index */
87 FETCH_OP_STACKP, /* Stack pointer */
88 FETCH_OP_RETVAL, /* Return value */
89 FETCH_OP_IMM, /* Immediate : .immediate */
90 FETCH_OP_COMM, /* Current comm */
91 FETCH_OP_ARG, /* Function argument : .param */
92 FETCH_OP_FOFFS, /* File offset: .immediate */
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 */
105 FETCH_OP_LP_ARRAY, /* Array: .param = loop count */
107 FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */
119 unsigned char basesize;
120 unsigned char lshift;
121 unsigned char rshift;
123 unsigned long immediate;
128 /* fetch + deref*N + store + mod + end <= 16, this allows N=12, enough */
129 #define FETCH_INSN_MAX 16
130 #define FETCH_TOKEN_COMM (-ECOMM)
132 /* Fetch type information table */
134 const char *name; /* Name of type */
135 size_t size; /* Byte size of type */
136 int is_signed; /* Signed flag */
137 print_type_func_t print; /* Print functions */
138 const char *fmt; /* Fromat string */
139 const char *fmttype; /* Name in format file */
142 /* For defining macros, define string/string_size types */
144 typedef u32 string_size;
146 #define PRINT_TYPE_FUNC_NAME(type) print_type_##type
147 #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
149 /* Printing in basic type function template */
150 #define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
151 int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\
152 extern const char PRINT_TYPE_FMT_NAME(type)[]
154 DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
155 DECLARE_BASIC_PRINT_TYPE_FUNC(u16);
156 DECLARE_BASIC_PRINT_TYPE_FUNC(u32);
157 DECLARE_BASIC_PRINT_TYPE_FUNC(u64);
158 DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
159 DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
160 DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
161 DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
162 DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
163 DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
164 DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
165 DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
167 DECLARE_BASIC_PRINT_TYPE_FUNC(string);
168 DECLARE_BASIC_PRINT_TYPE_FUNC(symbol);
170 /* Default (unsigned long) fetch type */
171 #define __DEFAULT_FETCH_TYPE(t) x##t
172 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
173 #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
174 #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
176 #define __ADDR_FETCH_TYPE(t) u##t
177 #define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t)
178 #define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG)
180 #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
184 .print = PRINT_TYPE_FUNC_NAME(ptype), \
185 .fmt = PRINT_TYPE_FMT_NAME(ptype), \
186 .fmttype = _fmttype, \
188 #define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
189 __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype)
190 #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
191 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype)
193 /* If ptype is an alias of atype, use this macro (show atype in format) */
194 #define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
195 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype)
197 #define ASSIGN_FETCH_TYPE_END {}
198 #define MAX_ARRAY_LEN 64
200 #ifdef CONFIG_KPROBE_EVENTS
201 bool trace_kprobe_on_func_entry(struct trace_event_call *call);
202 bool trace_kprobe_error_injectable(struct trace_event_call *call);
204 static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call)
209 static inline bool trace_kprobe_error_injectable(struct trace_event_call *call)
213 #endif /* CONFIG_KPROBE_EVENTS */
216 struct fetch_insn *code;
217 bool dynamic;/* Dynamic array (string) is used */
218 unsigned int offset; /* Offset from argument entry */
219 unsigned int count; /* Array count */
220 const char *name; /* Name of this argument */
221 const char *comm; /* Command of this argument */
222 char *fmt; /* Format string if needed */
223 const struct fetch_type *type; /* Type of this argument */
227 unsigned int flags; /* For TP_FLAG_* */
228 struct trace_event_class class;
229 struct trace_event_call call;
230 struct list_head files;
231 ssize_t size; /* trace entry size */
232 unsigned int nr_args;
233 struct probe_arg args[];
236 struct event_file_link {
237 struct trace_event_file *file;
238 struct list_head list;
241 static inline bool trace_probe_test_flag(struct trace_probe *tp,
244 return !!(tp->flags & flag);
247 static inline void trace_probe_set_flag(struct trace_probe *tp,
253 static inline void trace_probe_clear_flag(struct trace_probe *tp,
259 static inline bool trace_probe_is_enabled(struct trace_probe *tp)
261 return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE);
264 static inline bool trace_probe_is_registered(struct trace_probe *tp)
266 return trace_probe_test_flag(tp, TP_FLAG_REGISTERED);
269 static inline const char *trace_probe_name(struct trace_probe *tp)
271 return trace_event_name(&tp->call);
274 static inline const char *trace_probe_group_name(struct trace_probe *tp)
276 return tp->call.class->system;
279 static inline struct trace_event_call *
280 trace_probe_event_call(struct trace_probe *tp)
285 static inline int trace_probe_unregister_event_call(struct trace_probe *tp)
287 /* tp->event is unregistered in trace_remove_event_call() */
288 return trace_remove_event_call(&tp->call);
291 static inline bool trace_probe_has_single_file(struct trace_probe *tp)
293 return !!list_is_singular(&tp->files);
296 int trace_probe_init(struct trace_probe *tp, const char *event,
298 void trace_probe_cleanup(struct trace_probe *tp);
299 int trace_probe_register_event_call(struct trace_probe *tp);
300 int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file);
301 int trace_probe_remove_file(struct trace_probe *tp,
302 struct trace_event_file *file);
303 struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp,
304 struct trace_event_file *file);
306 #define trace_probe_for_each_link(pos, tp) \
307 list_for_each_entry(pos, &(tp)->files, list)
308 #define trace_probe_for_each_link_rcu(pos, tp) \
309 list_for_each_entry_rcu(pos, &(tp)->files, list)
311 /* Check the name is good for event/group/fields */
312 static inline bool is_good_name(const char *name)
314 if (!isalpha(*name) && *name != '_')
316 while (*++name != '\0') {
317 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
323 #define TPARG_FL_RETURN BIT(0)
324 #define TPARG_FL_KERNEL BIT(1)
325 #define TPARG_FL_FENTRY BIT(2)
326 #define TPARG_FL_MASK GENMASK(2, 0)
328 extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
329 char *arg, unsigned int flags);
331 extern int traceprobe_update_arg(struct probe_arg *arg);
332 extern void traceprobe_free_probe_arg(struct probe_arg *arg);
334 extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
335 int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
336 char *buf, int offset);
338 extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return);
340 #ifdef CONFIG_PERF_EVENTS
341 extern struct trace_event_call *
342 create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
344 extern void destroy_local_trace_kprobe(struct trace_event_call *event_call);
346 extern struct trace_event_call *
347 create_local_trace_uprobe(char *name, unsigned long offs,
348 unsigned long ref_ctr_offset, bool is_return);
349 extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
351 extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
352 size_t offset, struct trace_probe *tp);
356 C(FILE_NOT_FOUND, "Failed to find the given file"), \
357 C(NO_REGULAR_FILE, "Not a regular file"), \
358 C(BAD_REFCNT, "Invalid reference counter offset"), \
359 C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \
360 C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \
361 C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \
362 C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \
363 C(BAD_MAXACT, "Invalid maxactive number"), \
364 C(MAXACT_TOO_BIG, "Maxactive is too big"), \
365 C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \
366 C(BAD_RETPROBE, "Retprobe address must be an function entry"), \
367 C(NO_GROUP_NAME, "Group name is not specified"), \
368 C(GROUP_TOO_LONG, "Group name is too long"), \
369 C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \
370 C(NO_EVENT_NAME, "Event name is not specified"), \
371 C(EVENT_TOO_LONG, "Event name is too long"), \
372 C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \
373 C(RETVAL_ON_PROBE, "$retval is not available on probe"), \
374 C(BAD_STACK_NUM, "Invalid stack number"), \
375 C(BAD_ARG_NUM, "Invalid argument number"), \
376 C(BAD_VAR, "Invalid $-valiable specified"), \
377 C(BAD_REG_NAME, "Invalid register name"), \
378 C(BAD_MEM_ADDR, "Invalid memory address"), \
379 C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \
380 C(BAD_FILE_OFFS, "Invalid file offset value"), \
381 C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \
382 C(TOO_MANY_OPS, "Dereference is too much nested"), \
383 C(DEREF_NEED_BRACE, "Dereference needs a brace"), \
384 C(BAD_DEREF_OFFS, "Invalid dereference offset"), \
385 C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \
386 C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \
387 C(BAD_FETCH_ARG, "Invalid fetch argument"), \
388 C(ARRAY_NO_CLOSE, "Array is not closed"), \
389 C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \
390 C(BAD_ARRAY_NUM, "Invalid array size"), \
391 C(ARRAY_TOO_BIG, "Array number is too big"), \
392 C(BAD_TYPE, "Unknown type is specified"), \
393 C(BAD_STRING, "String accepts only memory argument"), \
394 C(BAD_BITFIELD, "Invalid bitfield"), \
395 C(ARG_NAME_TOO_LONG, "Argument name is too long"), \
396 C(NO_ARG_NAME, "Argument name is not specified"), \
397 C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \
398 C(USED_ARG_NAME, "This argument name is already used"), \
399 C(ARG_TOO_LONG, "Argument expression is too long"), \
400 C(NO_ARG_BODY, "No argument expression"), \
401 C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\
402 C(FAIL_REG_PROBE, "Failed to register probe event"),
405 #define C(a, b) TP_ERR_##a
410 /* Error text is defined in trace_probe.c */
412 struct trace_probe_log {
413 const char *subsystem;
419 void trace_probe_log_init(const char *subsystem, int argc, const char **argv);
420 void trace_probe_log_set_index(int index);
421 void trace_probe_log_clear(void);
422 void __trace_probe_log_err(int offset, int err);
424 #define trace_probe_log_err(offs, err) \
425 __trace_probe_log_err(offs, TP_ERR_##err)