Commit | Line | Data |
---|---|---|
47788c58 | 1 | #include <trace/syscall.h> |
1c569f02 | 2 | #include <trace/events/syscalls.h> |
f431b634 | 3 | #include <linux/syscalls.h> |
5a0e3ad6 | 4 | #include <linux/slab.h> |
ee08c6ec | 5 | #include <linux/kernel.h> |
56d82e00 | 6 | #include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */ |
fb34a08c | 7 | #include <linux/ftrace.h> |
cdd6c482 | 8 | #include <linux/perf_event.h> |
ee08c6ec FW |
9 | #include <asm/syscall.h> |
10 | ||
11 | #include "trace_output.h" | |
12 | #include "trace.h" | |
13 | ||
5be71b61 | 14 | static DEFINE_MUTEX(syscall_trace_lock); |
ee08c6ec | 15 | |
2425bcb9 | 16 | static int syscall_enter_register(struct trace_event_call *event, |
ceec0b6f | 17 | enum trace_reg type, void *data); |
2425bcb9 | 18 | static int syscall_exit_register(struct trace_event_call *event, |
ceec0b6f | 19 | enum trace_reg type, void *data); |
2239291a | 20 | |
2e33af02 | 21 | static struct list_head * |
2425bcb9 | 22 | syscall_get_enter_fields(struct trace_event_call *call) |
2e33af02 SR |
23 | { |
24 | struct syscall_metadata *entry = call->data; | |
25 | ||
26 | return &entry->enter_fields; | |
27 | } | |
28 | ||
3d56e331 SR |
29 | extern struct syscall_metadata *__start_syscalls_metadata[]; |
30 | extern struct syscall_metadata *__stop_syscalls_metadata[]; | |
c44fc770 FW |
31 | |
32 | static struct syscall_metadata **syscalls_metadata; | |
33 | ||
b2d55496 IM |
34 | #ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME |
35 | static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) | |
36 | { | |
37 | /* | |
38 | * Only compare after the "sys" prefix. Archs that use | |
39 | * syscall wrappers may have syscalls symbols aliases prefixed | |
36a78e9e | 40 | * with ".SyS" or ".sys" instead of "sys", leading to an unwanted |
b2d55496 IM |
41 | * mismatch. |
42 | */ | |
43 | return !strcmp(sym + 3, name + 3); | |
44 | } | |
45 | #endif | |
46 | ||
f431b634 SR |
47 | #ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS |
48 | /* | |
49 | * Some architectures that allow for 32bit applications | |
50 | * to run on a 64bit kernel, do not map the syscalls for | |
51 | * the 32bit tasks the same as they do for 64bit tasks. | |
52 | * | |
53 | * *cough*x86*cough* | |
54 | * | |
55 | * In such a case, instead of reporting the wrong syscalls, | |
56 | * simply ignore them. | |
57 | * | |
58 | * For an arch to ignore the compat syscalls it needs to | |
59 | * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as | |
60 | * define the function arch_trace_is_compat_syscall() to let | |
61 | * the tracing system know that it should ignore it. | |
62 | */ | |
63 | static int | |
64 | trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) | |
65 | { | |
66 | if (unlikely(arch_trace_is_compat_syscall(regs))) | |
67 | return -1; | |
68 | ||
69 | return syscall_get_nr(task, regs); | |
70 | } | |
71 | #else | |
72 | static inline int | |
73 | trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) | |
74 | { | |
75 | return syscall_get_nr(task, regs); | |
76 | } | |
77 | #endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */ | |
78 | ||
3d56e331 SR |
79 | static __init struct syscall_metadata * |
80 | find_syscall_meta(unsigned long syscall) | |
c44fc770 | 81 | { |
3d56e331 SR |
82 | struct syscall_metadata **start; |
83 | struct syscall_metadata **stop; | |
c44fc770 FW |
84 | char str[KSYM_SYMBOL_LEN]; |
85 | ||
86 | ||
3d56e331 SR |
87 | start = __start_syscalls_metadata; |
88 | stop = __stop_syscalls_metadata; | |
c44fc770 FW |
89 | kallsyms_lookup(syscall, NULL, NULL, NULL, str); |
90 | ||
ae07f551 IM |
91 | if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) |
92 | return NULL; | |
93 | ||
c44fc770 | 94 | for ( ; start < stop; start++) { |
b2d55496 | 95 | if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) |
3d56e331 | 96 | return *start; |
c44fc770 FW |
97 | } |
98 | return NULL; | |
99 | } | |
100 | ||
101 | static struct syscall_metadata *syscall_nr_to_meta(int nr) | |
102 | { | |
103 | if (!syscalls_metadata || nr >= NR_syscalls || nr < 0) | |
104 | return NULL; | |
105 | ||
106 | return syscalls_metadata[nr]; | |
107 | } | |
108 | ||
dbfeaa7a TZ |
109 | const char *get_syscall_name(int syscall) |
110 | { | |
111 | struct syscall_metadata *entry; | |
112 | ||
113 | entry = syscall_nr_to_meta(syscall); | |
114 | if (!entry) | |
115 | return NULL; | |
116 | ||
117 | return entry->name; | |
118 | } | |
119 | ||
6aea49cb | 120 | static enum print_line_t |
a9a57763 SR |
121 | print_syscall_enter(struct trace_iterator *iter, int flags, |
122 | struct trace_event *event) | |
bed1ffca | 123 | { |
983f938a | 124 | struct trace_array *tr = iter->tr; |
bed1ffca FW |
125 | struct trace_seq *s = &iter->seq; |
126 | struct trace_entry *ent = iter->ent; | |
127 | struct syscall_trace_enter *trace; | |
128 | struct syscall_metadata *entry; | |
183742f0 | 129 | int i, syscall; |
bed1ffca | 130 | |
64c12e04 | 131 | trace = (typeof(trace))ent; |
bed1ffca | 132 | syscall = trace->nr; |
bed1ffca | 133 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 134 | |
bed1ffca FW |
135 | if (!entry) |
136 | goto end; | |
137 | ||
32c0edae | 138 | if (entry->enter_event->event.type != ent->type) { |
64c12e04 JB |
139 | WARN_ON_ONCE(1); |
140 | goto end; | |
141 | } | |
142 | ||
183742f0 | 143 | trace_seq_printf(s, "%s(", entry->name); |
bed1ffca FW |
144 | |
145 | for (i = 0; i < entry->nb_args; i++) { | |
183742f0 SRRH |
146 | |
147 | if (trace_seq_has_overflowed(s)) | |
148 | goto end; | |
149 | ||
bed1ffca | 150 | /* parameter types */ |
983f938a | 151 | if (tr->trace_flags & TRACE_ITER_VERBOSE) |
183742f0 SRRH |
152 | trace_seq_printf(s, "%s ", entry->types[i]); |
153 | ||
bed1ffca | 154 | /* parameter values */ |
183742f0 SRRH |
155 | trace_seq_printf(s, "%s: %lx%s", entry->args[i], |
156 | trace->args[i], | |
157 | i == entry->nb_args - 1 ? "" : ", "); | |
bed1ffca FW |
158 | } |
159 | ||
183742f0 | 160 | trace_seq_putc(s, ')'); |
bed1ffca | 161 | end: |
183742f0 | 162 | trace_seq_putc(s, '\n'); |
4539f077 | 163 | |
183742f0 | 164 | return trace_handle_return(s); |
bed1ffca FW |
165 | } |
166 | ||
6aea49cb | 167 | static enum print_line_t |
a9a57763 SR |
168 | print_syscall_exit(struct trace_iterator *iter, int flags, |
169 | struct trace_event *event) | |
bed1ffca FW |
170 | { |
171 | struct trace_seq *s = &iter->seq; | |
172 | struct trace_entry *ent = iter->ent; | |
173 | struct syscall_trace_exit *trace; | |
174 | int syscall; | |
175 | struct syscall_metadata *entry; | |
bed1ffca | 176 | |
64c12e04 | 177 | trace = (typeof(trace))ent; |
bed1ffca | 178 | syscall = trace->nr; |
bed1ffca | 179 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 180 | |
bed1ffca | 181 | if (!entry) { |
146c3442 | 182 | trace_seq_putc(s, '\n'); |
183742f0 | 183 | goto out; |
bed1ffca FW |
184 | } |
185 | ||
32c0edae | 186 | if (entry->exit_event->event.type != ent->type) { |
64c12e04 JB |
187 | WARN_ON_ONCE(1); |
188 | return TRACE_TYPE_UNHANDLED; | |
189 | } | |
190 | ||
183742f0 | 191 | trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, |
bed1ffca | 192 | trace->ret); |
bed1ffca | 193 | |
183742f0 SRRH |
194 | out: |
195 | return trace_handle_return(s); | |
bed1ffca FW |
196 | } |
197 | ||
e6971969 LZ |
198 | extern char *__bad_type_size(void); |
199 | ||
026842d1 TS |
200 | #define SYSCALL_FIELD(type, field, name) \ |
201 | sizeof(type) != sizeof(trace.field) ? \ | |
e6971969 | 202 | __bad_type_size() : \ |
026842d1 TS |
203 | #type, #name, offsetof(typeof(trace), field), \ |
204 | sizeof(trace.field), is_signed_type(type) | |
e6971969 | 205 | |
3ddc77f6 LZ |
206 | static int __init |
207 | __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) | |
50307a45 LJ |
208 | { |
209 | int i; | |
210 | int pos = 0; | |
211 | ||
212 | /* When len=0, we just calculate the needed length */ | |
213 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
214 | ||
215 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
216 | for (i = 0; i < entry->nb_args; i++) { | |
217 | pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", | |
218 | entry->args[i], sizeof(unsigned long), | |
219 | i == entry->nb_args - 1 ? "" : ", "); | |
220 | } | |
221 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
222 | ||
223 | for (i = 0; i < entry->nb_args; i++) { | |
224 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
225 | ", ((unsigned long)(REC->%s))", entry->args[i]); | |
226 | } | |
227 | ||
228 | #undef LEN_OR_ZERO | |
229 | ||
230 | /* return the length of print_fmt */ | |
231 | return pos; | |
232 | } | |
233 | ||
2425bcb9 | 234 | static int __init set_syscall_print_fmt(struct trace_event_call *call) |
50307a45 LJ |
235 | { |
236 | char *print_fmt; | |
237 | int len; | |
238 | struct syscall_metadata *entry = call->data; | |
239 | ||
240 | if (entry->enter_event != call) { | |
241 | call->print_fmt = "\"0x%lx\", REC->ret"; | |
242 | return 0; | |
243 | } | |
244 | ||
245 | /* First: called with 0 length to calculate the needed length */ | |
246 | len = __set_enter_print_fmt(entry, NULL, 0); | |
247 | ||
248 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
249 | if (!print_fmt) | |
250 | return -ENOMEM; | |
251 | ||
252 | /* Second: actually write the @print_fmt */ | |
253 | __set_enter_print_fmt(entry, print_fmt, len + 1); | |
254 | call->print_fmt = print_fmt; | |
255 | ||
256 | return 0; | |
257 | } | |
258 | ||
2425bcb9 | 259 | static void __init free_syscall_print_fmt(struct trace_event_call *call) |
50307a45 LJ |
260 | { |
261 | struct syscall_metadata *entry = call->data; | |
262 | ||
263 | if (entry->enter_event == call) | |
264 | kfree(call->print_fmt); | |
265 | } | |
266 | ||
2425bcb9 | 267 | static int __init syscall_enter_define_fields(struct trace_event_call *call) |
540b7b8d LZ |
268 | { |
269 | struct syscall_trace_enter trace; | |
31c16b13 | 270 | struct syscall_metadata *meta = call->data; |
540b7b8d | 271 | int ret; |
540b7b8d LZ |
272 | int i; |
273 | int offset = offsetof(typeof(trace), args); | |
274 | ||
026842d1 TS |
275 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr, __syscall_nr), |
276 | FILTER_OTHER); | |
0f1ef51d LJ |
277 | if (ret) |
278 | return ret; | |
279 | ||
540b7b8d | 280 | for (i = 0; i < meta->nb_args; i++) { |
aeaeae11 FW |
281 | ret = trace_define_field(call, meta->types[i], |
282 | meta->args[i], offset, | |
43b51ead LZ |
283 | sizeof(unsigned long), 0, |
284 | FILTER_OTHER); | |
540b7b8d LZ |
285 | offset += sizeof(unsigned long); |
286 | } | |
287 | ||
288 | return ret; | |
289 | } | |
290 | ||
2425bcb9 | 291 | static int __init syscall_exit_define_fields(struct trace_event_call *call) |
540b7b8d LZ |
292 | { |
293 | struct syscall_trace_exit trace; | |
294 | int ret; | |
295 | ||
026842d1 TS |
296 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr, __syscall_nr), |
297 | FILTER_OTHER); | |
0f1ef51d LJ |
298 | if (ret) |
299 | return ret; | |
300 | ||
026842d1 | 301 | ret = trace_define_field(call, SYSCALL_FIELD(long, ret, ret), |
43b51ead | 302 | FILTER_OTHER); |
540b7b8d LZ |
303 | |
304 | return ret; | |
305 | } | |
306 | ||
12ab74ee | 307 | static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) |
ee08c6ec | 308 | { |
12ab74ee | 309 | struct trace_array *tr = data; |
7f1d2f82 | 310 | struct trace_event_file *trace_file; |
bed1ffca FW |
311 | struct syscall_trace_enter *entry; |
312 | struct syscall_metadata *sys_data; | |
313 | struct ring_buffer_event *event; | |
e77405ad | 314 | struct ring_buffer *buffer; |
11034ae9 J |
315 | unsigned long irq_flags; |
316 | int pc; | |
ee08c6ec | 317 | int syscall_nr; |
f431b634 | 318 | int size; |
ee08c6ec | 319 | |
f431b634 | 320 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 321 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
cd0980fc | 322 | return; |
d562aff9 TZ |
323 | |
324 | /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */ | |
7f1d2f82 SRRH |
325 | trace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]); |
326 | if (!trace_file) | |
d562aff9 TZ |
327 | return; |
328 | ||
09a5059a | 329 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 330 | return; |
ee08c6ec | 331 | |
bed1ffca FW |
332 | sys_data = syscall_nr_to_meta(syscall_nr); |
333 | if (!sys_data) | |
334 | return; | |
335 | ||
336 | size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; | |
337 | ||
11034ae9 J |
338 | local_save_flags(irq_flags); |
339 | pc = preempt_count(); | |
340 | ||
12883efb | 341 | buffer = tr->trace_buffer.buffer; |
12ab74ee | 342 | event = trace_buffer_lock_reserve(buffer, |
11034ae9 | 343 | sys_data->enter_event->event.type, size, irq_flags, pc); |
bed1ffca FW |
344 | if (!event) |
345 | return; | |
346 | ||
347 | entry = ring_buffer_event_data(event); | |
348 | entry->nr = syscall_nr; | |
349 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); | |
350 | ||
7f1d2f82 | 351 | event_trigger_unlock_commit(trace_file, buffer, event, entry, |
13a1e4ae | 352 | irq_flags, pc); |
ee08c6ec FW |
353 | } |
354 | ||
12ab74ee | 355 | static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) |
ee08c6ec | 356 | { |
12ab74ee | 357 | struct trace_array *tr = data; |
7f1d2f82 | 358 | struct trace_event_file *trace_file; |
bed1ffca FW |
359 | struct syscall_trace_exit *entry; |
360 | struct syscall_metadata *sys_data; | |
361 | struct ring_buffer_event *event; | |
e77405ad | 362 | struct ring_buffer *buffer; |
11034ae9 J |
363 | unsigned long irq_flags; |
364 | int pc; | |
ee08c6ec FW |
365 | int syscall_nr; |
366 | ||
f431b634 | 367 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 368 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
cd0980fc | 369 | return; |
d562aff9 TZ |
370 | |
371 | /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */ | |
7f1d2f82 SRRH |
372 | trace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]); |
373 | if (!trace_file) | |
d562aff9 TZ |
374 | return; |
375 | ||
09a5059a | 376 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 377 | return; |
ee08c6ec | 378 | |
bed1ffca FW |
379 | sys_data = syscall_nr_to_meta(syscall_nr); |
380 | if (!sys_data) | |
381 | return; | |
382 | ||
11034ae9 J |
383 | local_save_flags(irq_flags); |
384 | pc = preempt_count(); | |
385 | ||
12883efb | 386 | buffer = tr->trace_buffer.buffer; |
12ab74ee | 387 | event = trace_buffer_lock_reserve(buffer, |
11034ae9 J |
388 | sys_data->exit_event->event.type, sizeof(*entry), |
389 | irq_flags, pc); | |
bed1ffca FW |
390 | if (!event) |
391 | return; | |
392 | ||
393 | entry = ring_buffer_event_data(event); | |
394 | entry->nr = syscall_nr; | |
395 | entry->ret = syscall_get_return_value(current, regs); | |
396 | ||
7f1d2f82 | 397 | event_trigger_unlock_commit(trace_file, buffer, event, entry, |
13a1e4ae | 398 | irq_flags, pc); |
ee08c6ec FW |
399 | } |
400 | ||
7f1d2f82 | 401 | static int reg_event_syscall_enter(struct trace_event_file *file, |
2425bcb9 | 402 | struct trace_event_call *call) |
ee08c6ec | 403 | { |
12ab74ee | 404 | struct trace_array *tr = file->tr; |
fb34a08c JB |
405 | int ret = 0; |
406 | int num; | |
fb34a08c | 407 | |
c252f657 | 408 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 409 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
410 | return -ENOSYS; |
411 | mutex_lock(&syscall_trace_lock); | |
12ab74ee SR |
412 | if (!tr->sys_refcount_enter) |
413 | ret = register_trace_sys_enter(ftrace_syscall_enter, tr); | |
3b8e4273 | 414 | if (!ret) { |
d562aff9 | 415 | rcu_assign_pointer(tr->enter_syscall_files[num], file); |
12ab74ee | 416 | tr->sys_refcount_enter++; |
fb34a08c JB |
417 | } |
418 | mutex_unlock(&syscall_trace_lock); | |
419 | return ret; | |
ee08c6ec FW |
420 | } |
421 | ||
7f1d2f82 | 422 | static void unreg_event_syscall_enter(struct trace_event_file *file, |
2425bcb9 | 423 | struct trace_event_call *call) |
ee08c6ec | 424 | { |
12ab74ee | 425 | struct trace_array *tr = file->tr; |
fb34a08c | 426 | int num; |
ee08c6ec | 427 | |
c252f657 | 428 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 429 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
430 | return; |
431 | mutex_lock(&syscall_trace_lock); | |
12ab74ee | 432 | tr->sys_refcount_enter--; |
fb5a613b | 433 | RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL); |
12ab74ee SR |
434 | if (!tr->sys_refcount_enter) |
435 | unregister_trace_sys_enter(ftrace_syscall_enter, tr); | |
fb34a08c JB |
436 | mutex_unlock(&syscall_trace_lock); |
437 | } | |
ee08c6ec | 438 | |
7f1d2f82 | 439 | static int reg_event_syscall_exit(struct trace_event_file *file, |
2425bcb9 | 440 | struct trace_event_call *call) |
ee08c6ec | 441 | { |
12ab74ee | 442 | struct trace_array *tr = file->tr; |
fb34a08c JB |
443 | int ret = 0; |
444 | int num; | |
fb34a08c | 445 | |
c252f657 | 446 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 447 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
448 | return -ENOSYS; |
449 | mutex_lock(&syscall_trace_lock); | |
12ab74ee SR |
450 | if (!tr->sys_refcount_exit) |
451 | ret = register_trace_sys_exit(ftrace_syscall_exit, tr); | |
3b8e4273 | 452 | if (!ret) { |
d562aff9 | 453 | rcu_assign_pointer(tr->exit_syscall_files[num], file); |
12ab74ee | 454 | tr->sys_refcount_exit++; |
ee08c6ec | 455 | } |
fb34a08c JB |
456 | mutex_unlock(&syscall_trace_lock); |
457 | return ret; | |
458 | } | |
ee08c6ec | 459 | |
7f1d2f82 | 460 | static void unreg_event_syscall_exit(struct trace_event_file *file, |
2425bcb9 | 461 | struct trace_event_call *call) |
fb34a08c | 462 | { |
12ab74ee | 463 | struct trace_array *tr = file->tr; |
fb34a08c | 464 | int num; |
ee08c6ec | 465 | |
c252f657 | 466 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 467 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
468 | return; |
469 | mutex_lock(&syscall_trace_lock); | |
12ab74ee | 470 | tr->sys_refcount_exit--; |
fb5a613b | 471 | RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL); |
12ab74ee SR |
472 | if (!tr->sys_refcount_exit) |
473 | unregister_trace_sys_exit(ftrace_syscall_exit, tr); | |
fb34a08c | 474 | mutex_unlock(&syscall_trace_lock); |
ee08c6ec | 475 | } |
fb34a08c | 476 | |
2425bcb9 | 477 | static int __init init_syscall_trace(struct trace_event_call *call) |
a1301da0 LJ |
478 | { |
479 | int id; | |
ba976970 IM |
480 | int num; |
481 | ||
482 | num = ((struct syscall_metadata *)call->data)->syscall_nr; | |
483 | if (num < 0 || num >= NR_syscalls) { | |
484 | pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", | |
485 | ((struct syscall_metadata *)call->data)->name); | |
486 | return -ENOSYS; | |
487 | } | |
a1301da0 | 488 | |
50307a45 LJ |
489 | if (set_syscall_print_fmt(call) < 0) |
490 | return -ENOMEM; | |
491 | ||
c7ef3a90 SR |
492 | id = trace_event_raw_init(call); |
493 | ||
494 | if (id < 0) { | |
50307a45 | 495 | free_syscall_print_fmt(call); |
c7ef3a90 | 496 | return id; |
50307a45 | 497 | } |
c7ef3a90 SR |
498 | |
499 | return id; | |
a1301da0 LJ |
500 | } |
501 | ||
6f86ab9f VN |
502 | struct trace_event_functions enter_syscall_print_funcs = { |
503 | .trace = print_syscall_enter, | |
504 | }; | |
505 | ||
506 | struct trace_event_functions exit_syscall_print_funcs = { | |
507 | .trace = print_syscall_exit, | |
508 | }; | |
509 | ||
2425bcb9 | 510 | struct trace_event_class __refdata event_class_syscall_enter = { |
6f86ab9f VN |
511 | .system = "syscalls", |
512 | .reg = syscall_enter_register, | |
513 | .define_fields = syscall_enter_define_fields, | |
514 | .get_fields = syscall_get_enter_fields, | |
515 | .raw_init = init_syscall_trace, | |
516 | }; | |
517 | ||
2425bcb9 | 518 | struct trace_event_class __refdata event_class_syscall_exit = { |
6f86ab9f VN |
519 | .system = "syscalls", |
520 | .reg = syscall_exit_register, | |
521 | .define_fields = syscall_exit_define_fields, | |
522 | .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), | |
523 | .raw_init = init_syscall_trace, | |
524 | }; | |
525 | ||
c763ba06 | 526 | unsigned long __init __weak arch_syscall_addr(int nr) |
e7b8e675 MF |
527 | { |
528 | return (unsigned long)sys_call_table[nr]; | |
529 | } | |
530 | ||
5f893b26 | 531 | void __init init_ftrace_syscalls(void) |
c44fc770 FW |
532 | { |
533 | struct syscall_metadata *meta; | |
534 | unsigned long addr; | |
535 | int i; | |
536 | ||
47b0edcb TM |
537 | syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata), |
538 | GFP_KERNEL); | |
c44fc770 FW |
539 | if (!syscalls_metadata) { |
540 | WARN_ON(1); | |
5f893b26 | 541 | return; |
c44fc770 FW |
542 | } |
543 | ||
544 | for (i = 0; i < NR_syscalls; i++) { | |
545 | addr = arch_syscall_addr(i); | |
546 | meta = find_syscall_meta(addr); | |
c252f657 LJ |
547 | if (!meta) |
548 | continue; | |
549 | ||
550 | meta->syscall_nr = i; | |
c44fc770 FW |
551 | syscalls_metadata[i] = meta; |
552 | } | |
c44fc770 | 553 | } |
c44fc770 | 554 | |
07b139c8 | 555 | #ifdef CONFIG_PERF_EVENTS |
19007a67 | 556 | |
97d5a220 FW |
557 | static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); |
558 | static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); | |
559 | static int sys_perf_refcount_enter; | |
560 | static int sys_perf_refcount_exit; | |
f4b5ffcc | 561 | |
38516ab5 | 562 | static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
f4b5ffcc JB |
563 | { |
564 | struct syscall_metadata *sys_data; | |
20ab4425 | 565 | struct syscall_trace_enter *rec; |
1c024eca | 566 | struct hlist_head *head; |
f4b5ffcc | 567 | int syscall_nr; |
4ed7c92d | 568 | int rctx; |
19007a67 | 569 | int size; |
f4b5ffcc | 570 | |
f431b634 | 571 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 572 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
60916a93 | 573 | return; |
97d5a220 | 574 | if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) |
f4b5ffcc JB |
575 | return; |
576 | ||
577 | sys_data = syscall_nr_to_meta(syscall_nr); | |
578 | if (!sys_data) | |
579 | return; | |
580 | ||
421c7860 ON |
581 | head = this_cpu_ptr(sys_data->enter_event->perf_events); |
582 | if (hlist_empty(head)) | |
583 | return; | |
584 | ||
19007a67 FW |
585 | /* get the size after alignment with the u32 buffer size field */ |
586 | size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); | |
587 | size = ALIGN(size + sizeof(u32), sizeof(u64)); | |
588 | size -= sizeof(u32); | |
589 | ||
97d5a220 | 590 | rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, |
86038c5e | 591 | sys_data->enter_event->event.type, NULL, &rctx); |
430ad5a6 XG |
592 | if (!rec) |
593 | return; | |
20ab4425 | 594 | |
20ab4425 FW |
595 | rec->nr = syscall_nr; |
596 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, | |
597 | (unsigned long *)&rec->args); | |
e6dab5ff | 598 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); |
f4b5ffcc JB |
599 | } |
600 | ||
2425bcb9 | 601 | static int perf_sysenter_enable(struct trace_event_call *call) |
f4b5ffcc JB |
602 | { |
603 | int ret = 0; | |
604 | int num; | |
605 | ||
3bbe84e9 | 606 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
607 | |
608 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 609 | if (!sys_perf_refcount_enter) |
38516ab5 | 610 | ret = register_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
611 | if (ret) { |
612 | pr_info("event trace: Could not activate" | |
613 | "syscall entry trace point"); | |
614 | } else { | |
97d5a220 FW |
615 | set_bit(num, enabled_perf_enter_syscalls); |
616 | sys_perf_refcount_enter++; | |
f4b5ffcc JB |
617 | } |
618 | mutex_unlock(&syscall_trace_lock); | |
619 | return ret; | |
620 | } | |
621 | ||
2425bcb9 | 622 | static void perf_sysenter_disable(struct trace_event_call *call) |
f4b5ffcc JB |
623 | { |
624 | int num; | |
625 | ||
3bbe84e9 | 626 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
627 | |
628 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
629 | sys_perf_refcount_enter--; |
630 | clear_bit(num, enabled_perf_enter_syscalls); | |
631 | if (!sys_perf_refcount_enter) | |
38516ab5 | 632 | unregister_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
633 | mutex_unlock(&syscall_trace_lock); |
634 | } | |
635 | ||
38516ab5 | 636 | static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
f4b5ffcc JB |
637 | { |
638 | struct syscall_metadata *sys_data; | |
20ab4425 | 639 | struct syscall_trace_exit *rec; |
1c024eca | 640 | struct hlist_head *head; |
f4b5ffcc | 641 | int syscall_nr; |
4ed7c92d | 642 | int rctx; |
20ab4425 | 643 | int size; |
f4b5ffcc | 644 | |
f431b634 | 645 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 646 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
60916a93 | 647 | return; |
97d5a220 | 648 | if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) |
f4b5ffcc JB |
649 | return; |
650 | ||
651 | sys_data = syscall_nr_to_meta(syscall_nr); | |
652 | if (!sys_data) | |
653 | return; | |
654 | ||
421c7860 ON |
655 | head = this_cpu_ptr(sys_data->exit_event->perf_events); |
656 | if (hlist_empty(head)) | |
657 | return; | |
658 | ||
20ab4425 FW |
659 | /* We can probably do that at build time */ |
660 | size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); | |
661 | size -= sizeof(u32); | |
19007a67 | 662 | |
97d5a220 | 663 | rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, |
86038c5e | 664 | sys_data->exit_event->event.type, NULL, &rctx); |
430ad5a6 XG |
665 | if (!rec) |
666 | return; | |
20ab4425 | 667 | |
20ab4425 FW |
668 | rec->nr = syscall_nr; |
669 | rec->ret = syscall_get_return_value(current, regs); | |
e6dab5ff | 670 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); |
f4b5ffcc JB |
671 | } |
672 | ||
2425bcb9 | 673 | static int perf_sysexit_enable(struct trace_event_call *call) |
f4b5ffcc JB |
674 | { |
675 | int ret = 0; | |
676 | int num; | |
677 | ||
3bbe84e9 | 678 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
679 | |
680 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 681 | if (!sys_perf_refcount_exit) |
38516ab5 | 682 | ret = register_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
683 | if (ret) { |
684 | pr_info("event trace: Could not activate" | |
6574658b | 685 | "syscall exit trace point"); |
f4b5ffcc | 686 | } else { |
97d5a220 FW |
687 | set_bit(num, enabled_perf_exit_syscalls); |
688 | sys_perf_refcount_exit++; | |
f4b5ffcc JB |
689 | } |
690 | mutex_unlock(&syscall_trace_lock); | |
691 | return ret; | |
692 | } | |
693 | ||
2425bcb9 | 694 | static void perf_sysexit_disable(struct trace_event_call *call) |
f4b5ffcc JB |
695 | { |
696 | int num; | |
697 | ||
3bbe84e9 | 698 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
699 | |
700 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
701 | sys_perf_refcount_exit--; |
702 | clear_bit(num, enabled_perf_exit_syscalls); | |
703 | if (!sys_perf_refcount_exit) | |
38516ab5 | 704 | unregister_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
705 | mutex_unlock(&syscall_trace_lock); |
706 | } | |
707 | ||
07b139c8 | 708 | #endif /* CONFIG_PERF_EVENTS */ |
f4b5ffcc | 709 | |
2425bcb9 | 710 | static int syscall_enter_register(struct trace_event_call *event, |
ceec0b6f | 711 | enum trace_reg type, void *data) |
2239291a | 712 | { |
7f1d2f82 | 713 | struct trace_event_file *file = data; |
12ab74ee | 714 | |
2239291a SR |
715 | switch (type) { |
716 | case TRACE_REG_REGISTER: | |
12ab74ee | 717 | return reg_event_syscall_enter(file, event); |
2239291a | 718 | case TRACE_REG_UNREGISTER: |
12ab74ee | 719 | unreg_event_syscall_enter(file, event); |
2239291a SR |
720 | return 0; |
721 | ||
722 | #ifdef CONFIG_PERF_EVENTS | |
723 | case TRACE_REG_PERF_REGISTER: | |
724 | return perf_sysenter_enable(event); | |
725 | case TRACE_REG_PERF_UNREGISTER: | |
726 | perf_sysenter_disable(event); | |
727 | return 0; | |
ceec0b6f JO |
728 | case TRACE_REG_PERF_OPEN: |
729 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
730 | case TRACE_REG_PERF_ADD: |
731 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 732 | return 0; |
2239291a SR |
733 | #endif |
734 | } | |
735 | return 0; | |
736 | } | |
737 | ||
2425bcb9 | 738 | static int syscall_exit_register(struct trace_event_call *event, |
ceec0b6f | 739 | enum trace_reg type, void *data) |
2239291a | 740 | { |
7f1d2f82 | 741 | struct trace_event_file *file = data; |
12ab74ee | 742 | |
2239291a SR |
743 | switch (type) { |
744 | case TRACE_REG_REGISTER: | |
12ab74ee | 745 | return reg_event_syscall_exit(file, event); |
2239291a | 746 | case TRACE_REG_UNREGISTER: |
12ab74ee | 747 | unreg_event_syscall_exit(file, event); |
2239291a SR |
748 | return 0; |
749 | ||
750 | #ifdef CONFIG_PERF_EVENTS | |
751 | case TRACE_REG_PERF_REGISTER: | |
752 | return perf_sysexit_enable(event); | |
753 | case TRACE_REG_PERF_UNREGISTER: | |
754 | perf_sysexit_disable(event); | |
755 | return 0; | |
ceec0b6f JO |
756 | case TRACE_REG_PERF_OPEN: |
757 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
758 | case TRACE_REG_PERF_ADD: |
759 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 760 | return 0; |
2239291a SR |
761 | #endif |
762 | } | |
763 | return 0; | |
764 | } |