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 | ||
6aea49cb | 109 | static enum print_line_t |
a9a57763 SR |
110 | print_syscall_enter(struct trace_iterator *iter, int flags, |
111 | struct trace_event *event) | |
bed1ffca | 112 | { |
983f938a | 113 | struct trace_array *tr = iter->tr; |
bed1ffca FW |
114 | struct trace_seq *s = &iter->seq; |
115 | struct trace_entry *ent = iter->ent; | |
116 | struct syscall_trace_enter *trace; | |
117 | struct syscall_metadata *entry; | |
183742f0 | 118 | int i, syscall; |
bed1ffca | 119 | |
64c12e04 | 120 | trace = (typeof(trace))ent; |
bed1ffca | 121 | syscall = trace->nr; |
bed1ffca | 122 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 123 | |
bed1ffca FW |
124 | if (!entry) |
125 | goto end; | |
126 | ||
32c0edae | 127 | if (entry->enter_event->event.type != ent->type) { |
64c12e04 JB |
128 | WARN_ON_ONCE(1); |
129 | goto end; | |
130 | } | |
131 | ||
183742f0 | 132 | trace_seq_printf(s, "%s(", entry->name); |
bed1ffca FW |
133 | |
134 | for (i = 0; i < entry->nb_args; i++) { | |
183742f0 SRRH |
135 | |
136 | if (trace_seq_has_overflowed(s)) | |
137 | goto end; | |
138 | ||
bed1ffca | 139 | /* parameter types */ |
983f938a | 140 | if (tr->trace_flags & TRACE_ITER_VERBOSE) |
183742f0 SRRH |
141 | trace_seq_printf(s, "%s ", entry->types[i]); |
142 | ||
bed1ffca | 143 | /* parameter values */ |
183742f0 SRRH |
144 | trace_seq_printf(s, "%s: %lx%s", entry->args[i], |
145 | trace->args[i], | |
146 | i == entry->nb_args - 1 ? "" : ", "); | |
bed1ffca FW |
147 | } |
148 | ||
183742f0 | 149 | trace_seq_putc(s, ')'); |
bed1ffca | 150 | end: |
183742f0 | 151 | trace_seq_putc(s, '\n'); |
4539f077 | 152 | |
183742f0 | 153 | return trace_handle_return(s); |
bed1ffca FW |
154 | } |
155 | ||
6aea49cb | 156 | static enum print_line_t |
a9a57763 SR |
157 | print_syscall_exit(struct trace_iterator *iter, int flags, |
158 | struct trace_event *event) | |
bed1ffca FW |
159 | { |
160 | struct trace_seq *s = &iter->seq; | |
161 | struct trace_entry *ent = iter->ent; | |
162 | struct syscall_trace_exit *trace; | |
163 | int syscall; | |
164 | struct syscall_metadata *entry; | |
bed1ffca | 165 | |
64c12e04 | 166 | trace = (typeof(trace))ent; |
bed1ffca | 167 | syscall = trace->nr; |
bed1ffca | 168 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 169 | |
bed1ffca | 170 | if (!entry) { |
146c3442 | 171 | trace_seq_putc(s, '\n'); |
183742f0 | 172 | goto out; |
bed1ffca FW |
173 | } |
174 | ||
32c0edae | 175 | if (entry->exit_event->event.type != ent->type) { |
64c12e04 JB |
176 | WARN_ON_ONCE(1); |
177 | return TRACE_TYPE_UNHANDLED; | |
178 | } | |
179 | ||
183742f0 | 180 | trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, |
bed1ffca | 181 | trace->ret); |
bed1ffca | 182 | |
183742f0 SRRH |
183 | out: |
184 | return trace_handle_return(s); | |
bed1ffca FW |
185 | } |
186 | ||
e6971969 LZ |
187 | extern char *__bad_type_size(void); |
188 | ||
189 | #define SYSCALL_FIELD(type, name) \ | |
190 | sizeof(type) != sizeof(trace.name) ? \ | |
191 | __bad_type_size() : \ | |
26a50744 TZ |
192 | #type, #name, offsetof(typeof(trace), name), \ |
193 | sizeof(trace.name), is_signed_type(type) | |
e6971969 | 194 | |
3ddc77f6 LZ |
195 | static int __init |
196 | __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) | |
50307a45 LJ |
197 | { |
198 | int i; | |
199 | int pos = 0; | |
200 | ||
201 | /* When len=0, we just calculate the needed length */ | |
202 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
203 | ||
204 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
205 | for (i = 0; i < entry->nb_args; i++) { | |
206 | pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", | |
207 | entry->args[i], sizeof(unsigned long), | |
208 | i == entry->nb_args - 1 ? "" : ", "); | |
209 | } | |
210 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
211 | ||
212 | for (i = 0; i < entry->nb_args; i++) { | |
213 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
214 | ", ((unsigned long)(REC->%s))", entry->args[i]); | |
215 | } | |
216 | ||
217 | #undef LEN_OR_ZERO | |
218 | ||
219 | /* return the length of print_fmt */ | |
220 | return pos; | |
221 | } | |
222 | ||
2425bcb9 | 223 | static int __init set_syscall_print_fmt(struct trace_event_call *call) |
50307a45 LJ |
224 | { |
225 | char *print_fmt; | |
226 | int len; | |
227 | struct syscall_metadata *entry = call->data; | |
228 | ||
229 | if (entry->enter_event != call) { | |
230 | call->print_fmt = "\"0x%lx\", REC->ret"; | |
231 | return 0; | |
232 | } | |
233 | ||
234 | /* First: called with 0 length to calculate the needed length */ | |
235 | len = __set_enter_print_fmt(entry, NULL, 0); | |
236 | ||
237 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
238 | if (!print_fmt) | |
239 | return -ENOMEM; | |
240 | ||
241 | /* Second: actually write the @print_fmt */ | |
242 | __set_enter_print_fmt(entry, print_fmt, len + 1); | |
243 | call->print_fmt = print_fmt; | |
244 | ||
245 | return 0; | |
246 | } | |
247 | ||
2425bcb9 | 248 | static void __init free_syscall_print_fmt(struct trace_event_call *call) |
50307a45 LJ |
249 | { |
250 | struct syscall_metadata *entry = call->data; | |
251 | ||
252 | if (entry->enter_event == call) | |
253 | kfree(call->print_fmt); | |
254 | } | |
255 | ||
2425bcb9 | 256 | static int __init syscall_enter_define_fields(struct trace_event_call *call) |
540b7b8d LZ |
257 | { |
258 | struct syscall_trace_enter trace; | |
31c16b13 | 259 | struct syscall_metadata *meta = call->data; |
540b7b8d | 260 | int ret; |
540b7b8d LZ |
261 | int i; |
262 | int offset = offsetof(typeof(trace), args); | |
263 | ||
0f1ef51d LJ |
264 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
265 | if (ret) | |
266 | return ret; | |
267 | ||
540b7b8d | 268 | for (i = 0; i < meta->nb_args; i++) { |
aeaeae11 FW |
269 | ret = trace_define_field(call, meta->types[i], |
270 | meta->args[i], offset, | |
43b51ead LZ |
271 | sizeof(unsigned long), 0, |
272 | FILTER_OTHER); | |
540b7b8d LZ |
273 | offset += sizeof(unsigned long); |
274 | } | |
275 | ||
276 | return ret; | |
277 | } | |
278 | ||
2425bcb9 | 279 | static int __init syscall_exit_define_fields(struct trace_event_call *call) |
540b7b8d LZ |
280 | { |
281 | struct syscall_trace_exit trace; | |
282 | int ret; | |
283 | ||
0f1ef51d LJ |
284 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
285 | if (ret) | |
286 | return ret; | |
287 | ||
26a50744 | 288 | ret = trace_define_field(call, SYSCALL_FIELD(long, ret), |
43b51ead | 289 | FILTER_OTHER); |
540b7b8d LZ |
290 | |
291 | return ret; | |
292 | } | |
293 | ||
12ab74ee | 294 | static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) |
ee08c6ec | 295 | { |
12ab74ee | 296 | struct trace_array *tr = data; |
7f1d2f82 | 297 | struct trace_event_file *trace_file; |
bed1ffca FW |
298 | struct syscall_trace_enter *entry; |
299 | struct syscall_metadata *sys_data; | |
300 | struct ring_buffer_event *event; | |
e77405ad | 301 | struct ring_buffer *buffer; |
11034ae9 J |
302 | unsigned long irq_flags; |
303 | int pc; | |
ee08c6ec | 304 | int syscall_nr; |
f431b634 | 305 | int size; |
ee08c6ec | 306 | |
f431b634 | 307 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 308 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
cd0980fc | 309 | return; |
d562aff9 TZ |
310 | |
311 | /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */ | |
7f1d2f82 SRRH |
312 | trace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]); |
313 | if (!trace_file) | |
d562aff9 TZ |
314 | return; |
315 | ||
09a5059a | 316 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 317 | return; |
ee08c6ec | 318 | |
bed1ffca FW |
319 | sys_data = syscall_nr_to_meta(syscall_nr); |
320 | if (!sys_data) | |
321 | return; | |
322 | ||
323 | size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; | |
324 | ||
11034ae9 J |
325 | local_save_flags(irq_flags); |
326 | pc = preempt_count(); | |
327 | ||
12883efb | 328 | buffer = tr->trace_buffer.buffer; |
12ab74ee | 329 | event = trace_buffer_lock_reserve(buffer, |
11034ae9 | 330 | sys_data->enter_event->event.type, size, irq_flags, pc); |
bed1ffca FW |
331 | if (!event) |
332 | return; | |
333 | ||
334 | entry = ring_buffer_event_data(event); | |
335 | entry->nr = syscall_nr; | |
336 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); | |
337 | ||
7f1d2f82 | 338 | event_trigger_unlock_commit(trace_file, buffer, event, entry, |
13a1e4ae | 339 | irq_flags, pc); |
ee08c6ec FW |
340 | } |
341 | ||
12ab74ee | 342 | static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) |
ee08c6ec | 343 | { |
12ab74ee | 344 | struct trace_array *tr = data; |
7f1d2f82 | 345 | struct trace_event_file *trace_file; |
bed1ffca FW |
346 | struct syscall_trace_exit *entry; |
347 | struct syscall_metadata *sys_data; | |
348 | struct ring_buffer_event *event; | |
e77405ad | 349 | struct ring_buffer *buffer; |
11034ae9 J |
350 | unsigned long irq_flags; |
351 | int pc; | |
ee08c6ec FW |
352 | int syscall_nr; |
353 | ||
f431b634 | 354 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 355 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
cd0980fc | 356 | return; |
d562aff9 TZ |
357 | |
358 | /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */ | |
7f1d2f82 SRRH |
359 | trace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]); |
360 | if (!trace_file) | |
d562aff9 TZ |
361 | return; |
362 | ||
09a5059a | 363 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 364 | return; |
ee08c6ec | 365 | |
bed1ffca FW |
366 | sys_data = syscall_nr_to_meta(syscall_nr); |
367 | if (!sys_data) | |
368 | return; | |
369 | ||
11034ae9 J |
370 | local_save_flags(irq_flags); |
371 | pc = preempt_count(); | |
372 | ||
12883efb | 373 | buffer = tr->trace_buffer.buffer; |
12ab74ee | 374 | event = trace_buffer_lock_reserve(buffer, |
11034ae9 J |
375 | sys_data->exit_event->event.type, sizeof(*entry), |
376 | irq_flags, pc); | |
bed1ffca FW |
377 | if (!event) |
378 | return; | |
379 | ||
380 | entry = ring_buffer_event_data(event); | |
381 | entry->nr = syscall_nr; | |
382 | entry->ret = syscall_get_return_value(current, regs); | |
383 | ||
7f1d2f82 | 384 | event_trigger_unlock_commit(trace_file, buffer, event, entry, |
13a1e4ae | 385 | irq_flags, pc); |
ee08c6ec FW |
386 | } |
387 | ||
7f1d2f82 | 388 | static int reg_event_syscall_enter(struct trace_event_file *file, |
2425bcb9 | 389 | struct trace_event_call *call) |
ee08c6ec | 390 | { |
12ab74ee | 391 | struct trace_array *tr = file->tr; |
fb34a08c JB |
392 | int ret = 0; |
393 | int num; | |
fb34a08c | 394 | |
c252f657 | 395 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 396 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
397 | return -ENOSYS; |
398 | mutex_lock(&syscall_trace_lock); | |
12ab74ee SR |
399 | if (!tr->sys_refcount_enter) |
400 | ret = register_trace_sys_enter(ftrace_syscall_enter, tr); | |
3b8e4273 | 401 | if (!ret) { |
d562aff9 | 402 | rcu_assign_pointer(tr->enter_syscall_files[num], file); |
12ab74ee | 403 | tr->sys_refcount_enter++; |
fb34a08c JB |
404 | } |
405 | mutex_unlock(&syscall_trace_lock); | |
406 | return ret; | |
ee08c6ec FW |
407 | } |
408 | ||
7f1d2f82 | 409 | static void unreg_event_syscall_enter(struct trace_event_file *file, |
2425bcb9 | 410 | struct trace_event_call *call) |
ee08c6ec | 411 | { |
12ab74ee | 412 | struct trace_array *tr = file->tr; |
fb34a08c | 413 | int num; |
ee08c6ec | 414 | |
c252f657 | 415 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 416 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
417 | return; |
418 | mutex_lock(&syscall_trace_lock); | |
12ab74ee | 419 | tr->sys_refcount_enter--; |
fb5a613b | 420 | RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL); |
12ab74ee SR |
421 | if (!tr->sys_refcount_enter) |
422 | unregister_trace_sys_enter(ftrace_syscall_enter, tr); | |
fb34a08c JB |
423 | mutex_unlock(&syscall_trace_lock); |
424 | } | |
ee08c6ec | 425 | |
7f1d2f82 | 426 | static int reg_event_syscall_exit(struct trace_event_file *file, |
2425bcb9 | 427 | struct trace_event_call *call) |
ee08c6ec | 428 | { |
12ab74ee | 429 | struct trace_array *tr = file->tr; |
fb34a08c JB |
430 | int ret = 0; |
431 | int num; | |
fb34a08c | 432 | |
c252f657 | 433 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 434 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
435 | return -ENOSYS; |
436 | mutex_lock(&syscall_trace_lock); | |
12ab74ee SR |
437 | if (!tr->sys_refcount_exit) |
438 | ret = register_trace_sys_exit(ftrace_syscall_exit, tr); | |
3b8e4273 | 439 | if (!ret) { |
d562aff9 | 440 | rcu_assign_pointer(tr->exit_syscall_files[num], file); |
12ab74ee | 441 | tr->sys_refcount_exit++; |
ee08c6ec | 442 | } |
fb34a08c JB |
443 | mutex_unlock(&syscall_trace_lock); |
444 | return ret; | |
445 | } | |
ee08c6ec | 446 | |
7f1d2f82 | 447 | static void unreg_event_syscall_exit(struct trace_event_file *file, |
2425bcb9 | 448 | struct trace_event_call *call) |
fb34a08c | 449 | { |
12ab74ee | 450 | struct trace_array *tr = file->tr; |
fb34a08c | 451 | int num; |
ee08c6ec | 452 | |
c252f657 | 453 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 454 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
455 | return; |
456 | mutex_lock(&syscall_trace_lock); | |
12ab74ee | 457 | tr->sys_refcount_exit--; |
fb5a613b | 458 | RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL); |
12ab74ee SR |
459 | if (!tr->sys_refcount_exit) |
460 | unregister_trace_sys_exit(ftrace_syscall_exit, tr); | |
fb34a08c | 461 | mutex_unlock(&syscall_trace_lock); |
ee08c6ec | 462 | } |
fb34a08c | 463 | |
2425bcb9 | 464 | static int __init init_syscall_trace(struct trace_event_call *call) |
a1301da0 LJ |
465 | { |
466 | int id; | |
ba976970 IM |
467 | int num; |
468 | ||
469 | num = ((struct syscall_metadata *)call->data)->syscall_nr; | |
470 | if (num < 0 || num >= NR_syscalls) { | |
471 | pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", | |
472 | ((struct syscall_metadata *)call->data)->name); | |
473 | return -ENOSYS; | |
474 | } | |
a1301da0 | 475 | |
50307a45 LJ |
476 | if (set_syscall_print_fmt(call) < 0) |
477 | return -ENOMEM; | |
478 | ||
c7ef3a90 SR |
479 | id = trace_event_raw_init(call); |
480 | ||
481 | if (id < 0) { | |
50307a45 | 482 | free_syscall_print_fmt(call); |
c7ef3a90 | 483 | return id; |
50307a45 | 484 | } |
c7ef3a90 SR |
485 | |
486 | return id; | |
a1301da0 LJ |
487 | } |
488 | ||
6f86ab9f VN |
489 | struct trace_event_functions enter_syscall_print_funcs = { |
490 | .trace = print_syscall_enter, | |
491 | }; | |
492 | ||
493 | struct trace_event_functions exit_syscall_print_funcs = { | |
494 | .trace = print_syscall_exit, | |
495 | }; | |
496 | ||
2425bcb9 | 497 | struct trace_event_class __refdata event_class_syscall_enter = { |
6f86ab9f VN |
498 | .system = "syscalls", |
499 | .reg = syscall_enter_register, | |
500 | .define_fields = syscall_enter_define_fields, | |
501 | .get_fields = syscall_get_enter_fields, | |
502 | .raw_init = init_syscall_trace, | |
503 | }; | |
504 | ||
2425bcb9 | 505 | struct trace_event_class __refdata event_class_syscall_exit = { |
6f86ab9f VN |
506 | .system = "syscalls", |
507 | .reg = syscall_exit_register, | |
508 | .define_fields = syscall_exit_define_fields, | |
509 | .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), | |
510 | .raw_init = init_syscall_trace, | |
511 | }; | |
512 | ||
c763ba06 | 513 | unsigned long __init __weak arch_syscall_addr(int nr) |
e7b8e675 MF |
514 | { |
515 | return (unsigned long)sys_call_table[nr]; | |
516 | } | |
517 | ||
5f893b26 | 518 | void __init init_ftrace_syscalls(void) |
c44fc770 FW |
519 | { |
520 | struct syscall_metadata *meta; | |
521 | unsigned long addr; | |
522 | int i; | |
523 | ||
47b0edcb TM |
524 | syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata), |
525 | GFP_KERNEL); | |
c44fc770 FW |
526 | if (!syscalls_metadata) { |
527 | WARN_ON(1); | |
5f893b26 | 528 | return; |
c44fc770 FW |
529 | } |
530 | ||
531 | for (i = 0; i < NR_syscalls; i++) { | |
532 | addr = arch_syscall_addr(i); | |
533 | meta = find_syscall_meta(addr); | |
c252f657 LJ |
534 | if (!meta) |
535 | continue; | |
536 | ||
537 | meta->syscall_nr = i; | |
c44fc770 FW |
538 | syscalls_metadata[i] = meta; |
539 | } | |
c44fc770 | 540 | } |
c44fc770 | 541 | |
07b139c8 | 542 | #ifdef CONFIG_PERF_EVENTS |
19007a67 | 543 | |
97d5a220 FW |
544 | static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); |
545 | static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); | |
546 | static int sys_perf_refcount_enter; | |
547 | static int sys_perf_refcount_exit; | |
f4b5ffcc | 548 | |
38516ab5 | 549 | static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
f4b5ffcc JB |
550 | { |
551 | struct syscall_metadata *sys_data; | |
20ab4425 | 552 | struct syscall_trace_enter *rec; |
1c024eca | 553 | struct hlist_head *head; |
f4b5ffcc | 554 | int syscall_nr; |
4ed7c92d | 555 | int rctx; |
19007a67 | 556 | int size; |
f4b5ffcc | 557 | |
f431b634 | 558 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 559 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
60916a93 | 560 | return; |
97d5a220 | 561 | if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) |
f4b5ffcc JB |
562 | return; |
563 | ||
564 | sys_data = syscall_nr_to_meta(syscall_nr); | |
565 | if (!sys_data) | |
566 | return; | |
567 | ||
421c7860 ON |
568 | head = this_cpu_ptr(sys_data->enter_event->perf_events); |
569 | if (hlist_empty(head)) | |
570 | return; | |
571 | ||
19007a67 FW |
572 | /* get the size after alignment with the u32 buffer size field */ |
573 | size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); | |
574 | size = ALIGN(size + sizeof(u32), sizeof(u64)); | |
575 | size -= sizeof(u32); | |
576 | ||
97d5a220 | 577 | rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, |
86038c5e | 578 | sys_data->enter_event->event.type, NULL, &rctx); |
430ad5a6 XG |
579 | if (!rec) |
580 | return; | |
20ab4425 | 581 | |
20ab4425 FW |
582 | rec->nr = syscall_nr; |
583 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, | |
584 | (unsigned long *)&rec->args); | |
e6dab5ff | 585 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); |
f4b5ffcc JB |
586 | } |
587 | ||
2425bcb9 | 588 | static int perf_sysenter_enable(struct trace_event_call *call) |
f4b5ffcc JB |
589 | { |
590 | int ret = 0; | |
591 | int num; | |
592 | ||
3bbe84e9 | 593 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
594 | |
595 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 596 | if (!sys_perf_refcount_enter) |
38516ab5 | 597 | ret = register_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
598 | if (ret) { |
599 | pr_info("event trace: Could not activate" | |
600 | "syscall entry trace point"); | |
601 | } else { | |
97d5a220 FW |
602 | set_bit(num, enabled_perf_enter_syscalls); |
603 | sys_perf_refcount_enter++; | |
f4b5ffcc JB |
604 | } |
605 | mutex_unlock(&syscall_trace_lock); | |
606 | return ret; | |
607 | } | |
608 | ||
2425bcb9 | 609 | static void perf_sysenter_disable(struct trace_event_call *call) |
f4b5ffcc JB |
610 | { |
611 | int num; | |
612 | ||
3bbe84e9 | 613 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
614 | |
615 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
616 | sys_perf_refcount_enter--; |
617 | clear_bit(num, enabled_perf_enter_syscalls); | |
618 | if (!sys_perf_refcount_enter) | |
38516ab5 | 619 | unregister_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
620 | mutex_unlock(&syscall_trace_lock); |
621 | } | |
622 | ||
38516ab5 | 623 | static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
f4b5ffcc JB |
624 | { |
625 | struct syscall_metadata *sys_data; | |
20ab4425 | 626 | struct syscall_trace_exit *rec; |
1c024eca | 627 | struct hlist_head *head; |
f4b5ffcc | 628 | int syscall_nr; |
4ed7c92d | 629 | int rctx; |
20ab4425 | 630 | int size; |
f4b5ffcc | 631 | |
f431b634 | 632 | syscall_nr = trace_get_syscall_nr(current, regs); |
086ba77a | 633 | if (syscall_nr < 0 || syscall_nr >= NR_syscalls) |
60916a93 | 634 | return; |
97d5a220 | 635 | if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) |
f4b5ffcc JB |
636 | return; |
637 | ||
638 | sys_data = syscall_nr_to_meta(syscall_nr); | |
639 | if (!sys_data) | |
640 | return; | |
641 | ||
421c7860 ON |
642 | head = this_cpu_ptr(sys_data->exit_event->perf_events); |
643 | if (hlist_empty(head)) | |
644 | return; | |
645 | ||
20ab4425 FW |
646 | /* We can probably do that at build time */ |
647 | size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); | |
648 | size -= sizeof(u32); | |
19007a67 | 649 | |
97d5a220 | 650 | rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, |
86038c5e | 651 | sys_data->exit_event->event.type, NULL, &rctx); |
430ad5a6 XG |
652 | if (!rec) |
653 | return; | |
20ab4425 | 654 | |
20ab4425 FW |
655 | rec->nr = syscall_nr; |
656 | rec->ret = syscall_get_return_value(current, regs); | |
e6dab5ff | 657 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); |
f4b5ffcc JB |
658 | } |
659 | ||
2425bcb9 | 660 | static int perf_sysexit_enable(struct trace_event_call *call) |
f4b5ffcc JB |
661 | { |
662 | int ret = 0; | |
663 | int num; | |
664 | ||
3bbe84e9 | 665 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
666 | |
667 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 668 | if (!sys_perf_refcount_exit) |
38516ab5 | 669 | ret = register_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
670 | if (ret) { |
671 | pr_info("event trace: Could not activate" | |
6574658b | 672 | "syscall exit trace point"); |
f4b5ffcc | 673 | } else { |
97d5a220 FW |
674 | set_bit(num, enabled_perf_exit_syscalls); |
675 | sys_perf_refcount_exit++; | |
f4b5ffcc JB |
676 | } |
677 | mutex_unlock(&syscall_trace_lock); | |
678 | return ret; | |
679 | } | |
680 | ||
2425bcb9 | 681 | static void perf_sysexit_disable(struct trace_event_call *call) |
f4b5ffcc JB |
682 | { |
683 | int num; | |
684 | ||
3bbe84e9 | 685 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
686 | |
687 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
688 | sys_perf_refcount_exit--; |
689 | clear_bit(num, enabled_perf_exit_syscalls); | |
690 | if (!sys_perf_refcount_exit) | |
38516ab5 | 691 | unregister_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
692 | mutex_unlock(&syscall_trace_lock); |
693 | } | |
694 | ||
07b139c8 | 695 | #endif /* CONFIG_PERF_EVENTS */ |
f4b5ffcc | 696 | |
2425bcb9 | 697 | static int syscall_enter_register(struct trace_event_call *event, |
ceec0b6f | 698 | enum trace_reg type, void *data) |
2239291a | 699 | { |
7f1d2f82 | 700 | struct trace_event_file *file = data; |
12ab74ee | 701 | |
2239291a SR |
702 | switch (type) { |
703 | case TRACE_REG_REGISTER: | |
12ab74ee | 704 | return reg_event_syscall_enter(file, event); |
2239291a | 705 | case TRACE_REG_UNREGISTER: |
12ab74ee | 706 | unreg_event_syscall_enter(file, event); |
2239291a SR |
707 | return 0; |
708 | ||
709 | #ifdef CONFIG_PERF_EVENTS | |
710 | case TRACE_REG_PERF_REGISTER: | |
711 | return perf_sysenter_enable(event); | |
712 | case TRACE_REG_PERF_UNREGISTER: | |
713 | perf_sysenter_disable(event); | |
714 | return 0; | |
ceec0b6f JO |
715 | case TRACE_REG_PERF_OPEN: |
716 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
717 | case TRACE_REG_PERF_ADD: |
718 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 719 | return 0; |
2239291a SR |
720 | #endif |
721 | } | |
722 | return 0; | |
723 | } | |
724 | ||
2425bcb9 | 725 | static int syscall_exit_register(struct trace_event_call *event, |
ceec0b6f | 726 | enum trace_reg type, void *data) |
2239291a | 727 | { |
7f1d2f82 | 728 | struct trace_event_file *file = data; |
12ab74ee | 729 | |
2239291a SR |
730 | switch (type) { |
731 | case TRACE_REG_REGISTER: | |
12ab74ee | 732 | return reg_event_syscall_exit(file, event); |
2239291a | 733 | case TRACE_REG_UNREGISTER: |
12ab74ee | 734 | unreg_event_syscall_exit(file, event); |
2239291a SR |
735 | return 0; |
736 | ||
737 | #ifdef CONFIG_PERF_EVENTS | |
738 | case TRACE_REG_PERF_REGISTER: | |
739 | return perf_sysexit_enable(event); | |
740 | case TRACE_REG_PERF_UNREGISTER: | |
741 | perf_sysexit_disable(event); | |
742 | return 0; | |
ceec0b6f JO |
743 | case TRACE_REG_PERF_OPEN: |
744 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
745 | case TRACE_REG_PERF_ADD: |
746 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 747 | return 0; |
2239291a SR |
748 | #endif |
749 | } | |
750 | return 0; | |
751 | } |