Commit | Line | Data |
---|---|---|
baf20995 MD |
1 | /* |
2 | * ltt-debugfs-abi.c | |
3 | * | |
4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * LTTng debugfs ABI | |
7 | * | |
8 | * Mimic system calls for: | |
9 | * - session creation, returns a file descriptor or failure. | |
ad1c05e1 MD |
10 | * - channel creation, returns a file descriptor or failure. |
11 | * - Operates on a session file descriptor | |
12 | * - Takes all channel options as parameters. | |
13 | * - stream get, returns a file descriptor or failure. | |
14 | * - Operates on a channel file descriptor. | |
15 | * - stream notifier get, returns a file descriptor or failure. | |
16 | * - Operates on a channel file descriptor. | |
17 | * - event creation, returns a file descriptor or failure. | |
18 | * - Operates on a channel file descriptor | |
19 | * - Takes an event name as parameter | |
20 | * - Takes an instrumentation source as parameter | |
21 | * - e.g. tracepoints, dynamic_probes... | |
22 | * - Takes instrumentation source specific arguments. | |
baf20995 MD |
23 | */ |
24 | ||
11b5a3c2 | 25 | #include <linux/module.h> |
baf20995 | 26 | #include <linux/debugfs.h> |
11b5a3c2 MD |
27 | #include <linux/anon_inodes.h> |
28 | #include <linux/file.h> | |
29 | #include <linux/uaccess.h> | |
30 | #include <linux/slab.h> | |
b13f3ebe | 31 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
f3bc08c5 | 32 | #include "wrapper/ringbuffer/vfs.h" |
11b5a3c2 | 33 | #include "ltt-debugfs-abi.h" |
ad1c05e1 | 34 | #include "ltt-events.h" |
baf20995 MD |
35 | |
36 | /* | |
37 | * This is LTTng's own personal way to create a system call as an external | |
38 | * module. We use ioctl() on /sys/kernel/debug/lttng. | |
39 | */ | |
40 | ||
41 | static struct dentry *lttng_dentry; | |
ad1c05e1 MD |
42 | static const struct file_operations lttng_fops; |
43 | static const struct file_operations lttng_session_fops; | |
44 | static const struct file_operations lttng_channel_fops; | |
5dbbdb43 | 45 | static const struct file_operations lttng_metadata_fops; |
305d3e42 | 46 | static const struct file_operations lttng_event_fops; |
baf20995 | 47 | |
5dbbdb43 MD |
48 | enum channel_type { |
49 | PER_CPU_CHANNEL, | |
50 | GLOBAL_CHANNEL, | |
51 | METADATA_CHANNEL, | |
52 | }; | |
53 | ||
ad1c05e1 | 54 | static |
baf20995 MD |
55 | int lttng_abi_create_session(void) |
56 | { | |
57 | struct ltt_session *session; | |
c0e31d2e | 58 | struct file *session_file; |
11b5a3c2 | 59 | int session_fd, ret; |
baf20995 | 60 | |
653fe716 | 61 | session = ltt_session_create(); |
baf20995 MD |
62 | if (!session) |
63 | return -ENOMEM; | |
1c25284c | 64 | session_fd = get_unused_fd(); |
baf20995 MD |
65 | if (session_fd < 0) { |
66 | ret = session_fd; | |
67 | goto fd_error; | |
68 | } | |
c0e31d2e | 69 | session_file = anon_inode_getfile("[lttng_session]", |
ad1c05e1 | 70 | <tng_session_fops, |
baf20995 | 71 | session, O_RDWR); |
c0e31d2e MD |
72 | if (IS_ERR(session_file)) { |
73 | ret = PTR_ERR(session_file); | |
baf20995 MD |
74 | goto file_error; |
75 | } | |
c0e31d2e MD |
76 | session->file = session_file; |
77 | fd_install(session_fd, session_file); | |
baf20995 MD |
78 | return session_fd; |
79 | ||
80 | file_error: | |
81 | put_unused_fd(session_fd); | |
82 | fd_error: | |
83 | ltt_session_destroy(session); | |
84 | return ret; | |
85 | } | |
86 | ||
ad1c05e1 MD |
87 | /** |
88 | * lttng_ioctl - lttng syscall through ioctl | |
89 | * | |
c0e31d2e | 90 | * @file: the file |
ad1c05e1 MD |
91 | * @cmd: the command |
92 | * @arg: command arg | |
93 | * | |
94 | * This ioctl implements lttng commands: | |
95 | * LTTNG_SESSION | |
96 | * Returns a LTTng trace session file descriptor | |
97 | * | |
98 | * The returned session will be deleted when its file descriptor is closed. | |
99 | */ | |
100 | static | |
c0e31d2e | 101 | long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 MD |
102 | { |
103 | switch (cmd) { | |
104 | case LTTNG_SESSION: | |
105 | return lttng_abi_create_session(); | |
106 | default: | |
107 | return -ENOIOCTLCMD; | |
108 | } | |
109 | } | |
110 | ||
ad1c05e1 MD |
111 | static const struct file_operations lttng_fops = { |
112 | .unlocked_ioctl = lttng_ioctl, | |
113 | #ifdef CONFIG_COMPAT | |
03037b98 | 114 | .compat_ioctl = lttng_ioctl, |
ad1c05e1 | 115 | #endif |
11b5a3c2 | 116 | }; |
ad1c05e1 | 117 | |
5dbbdb43 MD |
118 | /* |
119 | * We tolerate no failure in this function (if one happens, we print a dmesg | |
120 | * error, but cannot return any error, because the channel information is | |
121 | * invariant. | |
122 | */ | |
123 | static | |
124 | void lttng_metadata_create_events(struct file *channel_file) | |
125 | { | |
126 | struct ltt_channel *channel = channel_file->private_data; | |
127 | char *event_name = "lttng-metadata"; | |
128 | struct ltt_event *event; | |
129 | int ret; | |
130 | void *probe; | |
131 | ||
132 | probe = ltt_probe_get(event_name); | |
133 | if (!probe) { | |
134 | ret = -ENOENT; | |
135 | goto probe_error; | |
136 | } | |
137 | /* | |
138 | * We tolerate no failure path after event creation. It will stay | |
139 | * invariant for the rest of the session. | |
140 | */ | |
141 | event = ltt_event_create(channel, event_name, INSTRUM_TRACEPOINTS, | |
142 | probe, NULL); | |
143 | if (!event) { | |
144 | goto event_error; | |
145 | ret = -EEXIST; | |
146 | } | |
147 | return; | |
148 | ||
149 | event_error: | |
150 | ltt_probe_put(probe); | |
151 | probe_error: | |
152 | WARN_ON(1); | |
153 | return; /* not allowed to return error */ | |
154 | } | |
155 | ||
156 | static | |
c0e31d2e | 157 | int lttng_abi_create_channel(struct file *session_file, |
5dbbdb43 MD |
158 | struct lttng_channel __user *uchan_param, |
159 | enum channel_type channel_type) | |
baf20995 | 160 | { |
c0e31d2e | 161 | struct ltt_session *session = session_file->private_data; |
5dbbdb43 MD |
162 | const struct file_operations *fops; |
163 | const char *transport_name; | |
baf20995 | 164 | struct ltt_channel *chan; |
c0e31d2e | 165 | struct file *chan_file; |
baf20995 MD |
166 | struct lttng_channel chan_param; |
167 | int chan_fd; | |
ad1c05e1 | 168 | int ret = 0; |
baf20995 | 169 | |
653fe716 | 170 | if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param))) |
baf20995 | 171 | return -EFAULT; |
1c25284c | 172 | chan_fd = get_unused_fd(); |
baf20995 MD |
173 | if (chan_fd < 0) { |
174 | ret = chan_fd; | |
175 | goto fd_error; | |
176 | } | |
c0e31d2e | 177 | chan_file = anon_inode_getfile("[lttng_channel]", |
ad1c05e1 | 178 | <tng_channel_fops, |
03037b98 | 179 | NULL, O_RDWR); |
c0e31d2e MD |
180 | if (IS_ERR(chan_file)) { |
181 | ret = PTR_ERR(chan_file); | |
baf20995 MD |
182 | goto file_error; |
183 | } | |
5dbbdb43 MD |
184 | switch (channel_type) { |
185 | case PER_CPU_CHANNEL: | |
186 | transport_name = chan_param.overwrite ? | |
187 | "relay-overwrite" : "relay-discard"; | |
188 | fops = <tng_channel_fops; | |
189 | break; | |
190 | case GLOBAL_CHANNEL: | |
191 | transport_name = chan_param.overwrite ? | |
192 | "global-relay-overwrite" : "global-relay-discard"; | |
193 | fops = <tng_channel_fops; | |
194 | break; | |
195 | case METADATA_CHANNEL: | |
196 | transport_name = "global-relay-discard"; | |
197 | fops = <tng_metadata_fops; | |
198 | break; | |
199 | default: | |
200 | transport_name = "<unknown>"; | |
201 | break; | |
202 | } | |
03037b98 MD |
203 | /* |
204 | * We tolerate no failure path after channel creation. It will stay | |
205 | * invariant for the rest of the session. | |
206 | */ | |
5dbbdb43 | 207 | chan = ltt_channel_create(session, transport_name, NULL, |
11b5a3c2 MD |
208 | chan_param.subbuf_size, |
209 | chan_param.num_subbuf, | |
210 | chan_param.switch_timer_interval, | |
211 | chan_param.read_timer_interval); | |
03037b98 | 212 | if (!chan) { |
f3d01b96 | 213 | ret = -EINVAL; |
03037b98 MD |
214 | goto chan_error; |
215 | } | |
11b5a3c2 | 216 | chan->file = chan_file; |
c0e31d2e MD |
217 | chan_file->private_data = chan; |
218 | fd_install(chan_fd, chan_file); | |
5dbbdb43 MD |
219 | if (channel_type == METADATA_CHANNEL) |
220 | lttng_metadata_create_events(chan_file); | |
221 | ||
ad1c05e1 | 222 | /* The channel created holds a reference on the session */ |
b0caa15a | 223 | atomic_long_inc(&session_file->f_count); |
ad1c05e1 | 224 | |
baf20995 MD |
225 | return chan_fd; |
226 | ||
03037b98 | 227 | chan_error: |
c0e31d2e | 228 | fput(chan_file); |
baf20995 MD |
229 | file_error: |
230 | put_unused_fd(chan_fd); | |
231 | fd_error: | |
baf20995 MD |
232 | return ret; |
233 | } | |
234 | ||
235 | /** | |
ad1c05e1 | 236 | * lttng_session_ioctl - lttng session fd ioctl |
baf20995 | 237 | * |
c0e31d2e | 238 | * @file: the file |
baf20995 MD |
239 | * @cmd: the command |
240 | * @arg: command arg | |
241 | * | |
242 | * This ioctl implements lttng commands: | |
baf20995 MD |
243 | * LTTNG_CHANNEL |
244 | * Returns a LTTng channel file descriptor | |
ad1c05e1 MD |
245 | * |
246 | * The returned channel will be deleted when its file descriptor is closed. | |
247 | */ | |
248 | static | |
c0e31d2e | 249 | long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 | 250 | { |
c0e31d2e MD |
251 | struct ltt_session *session = file->private_data; |
252 | ||
ad1c05e1 MD |
253 | switch (cmd) { |
254 | case LTTNG_CHANNEL: | |
5dbbdb43 MD |
255 | return lttng_abi_create_channel(file, |
256 | (struct lttng_channel __user *)arg, | |
257 | PER_CPU_CHANNEL); | |
c0e31d2e MD |
258 | case LTTNG_SESSION_START: |
259 | return ltt_session_start(session); | |
260 | case LTTNG_SESSION_STOP: | |
261 | return ltt_session_stop(session); | |
5dbbdb43 MD |
262 | case LTTNG_METADATA: |
263 | return lttng_abi_create_channel(file, | |
264 | (struct lttng_channel __user *)arg, | |
265 | METADATA_CHANNEL); | |
ad1c05e1 MD |
266 | default: |
267 | return -ENOIOCTLCMD; | |
268 | } | |
269 | } | |
270 | ||
03037b98 MD |
271 | /* |
272 | * Called when the last file reference is dropped. | |
273 | * | |
274 | * Big fat note: channels and events are invariant for the whole session after | |
275 | * their creation. So this session destruction also destroys all channel and | |
276 | * event structures specific to this session (they are not destroyed when their | |
277 | * individual file is released). | |
278 | */ | |
ad1c05e1 | 279 | static |
03037b98 | 280 | int lttng_session_release(struct inode *inode, struct file *file) |
ad1c05e1 | 281 | { |
03037b98 | 282 | struct ltt_session *session = file->private_data; |
c269fff4 MD |
283 | |
284 | if (session) | |
285 | ltt_session_destroy(session); | |
11b5a3c2 | 286 | return 0; |
ad1c05e1 | 287 | } |
ad1c05e1 MD |
288 | |
289 | static const struct file_operations lttng_session_fops = { | |
03037b98 | 290 | .release = lttng_session_release, |
ad1c05e1 MD |
291 | .unlocked_ioctl = lttng_session_ioctl, |
292 | #ifdef CONFIG_COMPAT | |
03037b98 | 293 | .compat_ioctl = lttng_session_ioctl, |
ad1c05e1 | 294 | #endif |
11b5a3c2 | 295 | }; |
ad1c05e1 MD |
296 | |
297 | static | |
c0e31d2e | 298 | int lttng_abi_open_stream(struct file *channel_file) |
ad1c05e1 | 299 | { |
c0e31d2e | 300 | struct ltt_channel *channel = channel_file->private_data; |
ad1c05e1 MD |
301 | struct lib_ring_buffer *buf; |
302 | int stream_fd, ret; | |
11b5a3c2 | 303 | struct file *stream_file; |
ad1c05e1 | 304 | |
11b5a3c2 | 305 | buf = channel->ops->buffer_read_open(channel->chan); |
ad1c05e1 MD |
306 | if (!buf) |
307 | return -ENOENT; | |
308 | ||
1c25284c | 309 | stream_fd = get_unused_fd(); |
ad1c05e1 MD |
310 | if (stream_fd < 0) { |
311 | ret = stream_fd; | |
312 | goto fd_error; | |
313 | } | |
c0e31d2e | 314 | stream_file = anon_inode_getfile("[lttng_stream]", |
7f57c73c | 315 | &lib_ring_buffer_file_operations, |
ad1c05e1 | 316 | buf, O_RDWR); |
c0e31d2e MD |
317 | if (IS_ERR(stream_file)) { |
318 | ret = PTR_ERR(stream_file); | |
ad1c05e1 MD |
319 | goto file_error; |
320 | } | |
409453cb MD |
321 | /* |
322 | * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor | |
323 | * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this | |
324 | * file descriptor, so we set FMODE_PREAD here. | |
325 | */ | |
d7b6f197 | 326 | stream_file->f_mode |= FMODE_PREAD; |
c0e31d2e | 327 | fd_install(stream_fd, stream_file); |
dda6a249 MD |
328 | /* |
329 | * The stream holds a reference to the channel within the generic ring | |
330 | * buffer library, so no need to hold a refcount on the channel and | |
331 | * session files here. | |
332 | */ | |
ad1c05e1 MD |
333 | return stream_fd; |
334 | ||
335 | file_error: | |
336 | put_unused_fd(stream_fd); | |
337 | fd_error: | |
11b5a3c2 | 338 | channel->ops->buffer_read_close(buf); |
ad1c05e1 MD |
339 | return ret; |
340 | } | |
341 | ||
653fe716 | 342 | static |
c0e31d2e | 343 | int lttng_abi_create_event(struct file *channel_file, |
653fe716 MD |
344 | struct lttng_event __user *uevent_param) |
345 | { | |
c0e31d2e | 346 | struct ltt_channel *channel = channel_file->private_data; |
653fe716 MD |
347 | struct ltt_event *event; |
348 | char *event_name; | |
349 | struct lttng_event event_param; | |
350 | int event_fd, ret; | |
11b5a3c2 | 351 | struct file *event_file; |
dda6a249 | 352 | void *probe; |
653fe716 MD |
353 | |
354 | if (copy_from_user(&event_param, uevent_param, sizeof(event_param))) | |
355 | return -EFAULT; | |
356 | event_name = kmalloc(PATH_MAX, GFP_KERNEL); | |
357 | if (!event_name) | |
358 | return -ENOMEM; | |
981616e8 | 359 | if (strncpy_from_user(event_name, uevent_param->name, PATH_MAX) < 0) { |
653fe716 MD |
360 | ret = -EFAULT; |
361 | goto name_error; | |
362 | } | |
363 | event_name[PATH_MAX - 1] = '\0'; | |
dda6a249 MD |
364 | |
365 | probe = ltt_probe_get(event_name); | |
366 | if (!probe) { | |
367 | ret = -ENOENT; | |
368 | goto probe_error; | |
369 | } | |
1c25284c | 370 | event_fd = get_unused_fd(); |
653fe716 MD |
371 | if (event_fd < 0) { |
372 | ret = event_fd; | |
373 | goto fd_error; | |
374 | } | |
c0e31d2e | 375 | event_file = anon_inode_getfile("[lttng_event]", |
3b923e5b | 376 | <tng_event_fops, |
03037b98 | 377 | NULL, O_RDWR); |
c0e31d2e MD |
378 | if (IS_ERR(event_file)) { |
379 | ret = PTR_ERR(event_file); | |
653fe716 MD |
380 | goto file_error; |
381 | } | |
03037b98 MD |
382 | /* |
383 | * We tolerate no failure path after event creation. It will stay | |
384 | * invariant for the rest of the session. | |
385 | */ | |
11b5a3c2 | 386 | event = ltt_event_create(channel, event_name, event_param.itype, |
dda6a249 | 387 | probe, NULL); |
03037b98 MD |
388 | if (!event) { |
389 | goto event_error; | |
390 | ret = -EEXIST; | |
391 | } | |
c0e31d2e MD |
392 | event_file->private_data = event; |
393 | fd_install(event_fd, event_file); | |
653fe716 | 394 | /* The event holds a reference on the channel */ |
b0caa15a | 395 | atomic_long_inc(&channel_file->f_count); |
03037b98 | 396 | kfree(event_name); |
653fe716 MD |
397 | return event_fd; |
398 | ||
03037b98 | 399 | event_error: |
c0e31d2e | 400 | fput(event_file); |
653fe716 MD |
401 | file_error: |
402 | put_unused_fd(event_fd); | |
403 | fd_error: | |
dda6a249 MD |
404 | ltt_probe_put(probe); |
405 | probe_error: | |
653fe716 MD |
406 | name_error: |
407 | kfree(event_name); | |
408 | return ret; | |
409 | } | |
ad1c05e1 MD |
410 | |
411 | /** | |
412 | * lttng_channel_ioctl - lttng syscall through ioctl | |
413 | * | |
c0e31d2e | 414 | * @file: the file |
ad1c05e1 MD |
415 | * @cmd: the command |
416 | * @arg: command arg | |
417 | * | |
418 | * This ioctl implements lttng commands: | |
419 | * LTTNG_STREAM | |
420 | * Returns an event stream file descriptor or failure. | |
421 | * (typically, one event stream records events from one CPU) | |
baf20995 | 422 | * LTTNG_EVENT |
ad1c05e1 | 423 | * Returns an event file descriptor or failure. |
baf20995 | 424 | * |
baf20995 MD |
425 | * Channel and event file descriptors also hold a reference on the session. |
426 | */ | |
ad1c05e1 | 427 | static |
c0e31d2e | 428 | long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
baf20995 | 429 | { |
baf20995 | 430 | switch (cmd) { |
ad1c05e1 | 431 | case LTTNG_STREAM: |
c0e31d2e | 432 | return lttng_abi_open_stream(file); |
baf20995 | 433 | case LTTNG_EVENT: |
c0e31d2e | 434 | return lttng_abi_create_event(file, (struct lttng_event __user *)arg); |
baf20995 MD |
435 | default: |
436 | return -ENOIOCTLCMD; | |
437 | } | |
438 | } | |
439 | ||
5dbbdb43 MD |
440 | /** |
441 | * lttng_metadata_ioctl - lttng syscall through ioctl | |
442 | * | |
443 | * @file: the file | |
444 | * @cmd: the command | |
445 | * @arg: command arg | |
446 | * | |
447 | * This ioctl implements lttng commands: | |
448 | * LTTNG_STREAM | |
449 | * Returns an event stream file descriptor or failure. | |
450 | * | |
451 | * Channel and event file descriptors also hold a reference on the session. | |
452 | */ | |
453 | static | |
454 | long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
455 | { | |
456 | switch (cmd) { | |
457 | case LTTNG_STREAM: | |
458 | return lttng_abi_open_stream(file); | |
459 | default: | |
460 | return -ENOIOCTLCMD; | |
461 | } | |
462 | } | |
463 | ||
3b923e5b MD |
464 | /* TODO: poll */ |
465 | #if 0 | |
653fe716 MD |
466 | /** |
467 | * lttng_channel_poll - lttng stream addition/removal monitoring | |
468 | * | |
c0e31d2e | 469 | * @file: the file |
653fe716 MD |
470 | * @wait: poll table |
471 | */ | |
c0e31d2e | 472 | unsigned int lttng_channel_poll(struct file *file, poll_table *wait) |
653fe716 | 473 | { |
c0e31d2e | 474 | struct ltt_channel *channel = file->private_data; |
653fe716 MD |
475 | unsigned int mask = 0; |
476 | ||
c0e31d2e | 477 | if (file->f_mode & FMODE_READ) { |
653fe716 | 478 | poll_wait_set_exclusive(wait); |
c0e31d2e | 479 | poll_wait(file, &channel->notify_wait, wait); |
653fe716 MD |
480 | |
481 | /* TODO: identify when the channel is being finalized. */ | |
482 | if (finalized) | |
483 | return POLLHUP; | |
484 | else | |
485 | return POLLIN | POLLRDNORM; | |
486 | } | |
487 | return mask; | |
488 | ||
489 | } | |
3b923e5b | 490 | #endif //0 |
653fe716 | 491 | |
0a84a57f MD |
492 | static |
493 | int lttng_channel_release(struct inode *inode, struct file *file) | |
494 | { | |
495 | struct ltt_channel *channel = file->private_data; | |
c269fff4 MD |
496 | |
497 | if (channel) | |
498 | fput(channel->session->file); | |
0a84a57f MD |
499 | return 0; |
500 | } | |
501 | ||
ad1c05e1 | 502 | static const struct file_operations lttng_channel_fops = { |
03037b98 | 503 | .release = lttng_channel_release, |
3b923e5b MD |
504 | /* TODO */ |
505 | #if 0 | |
653fe716 | 506 | .poll = lttng_channel_poll, |
3b923e5b | 507 | #endif //0 |
ad1c05e1 | 508 | .unlocked_ioctl = lttng_channel_ioctl, |
baf20995 | 509 | #ifdef CONFIG_COMPAT |
03037b98 | 510 | .compat_ioctl = lttng_channel_ioctl, |
baf20995 | 511 | #endif |
11b5a3c2 | 512 | }; |
baf20995 | 513 | |
5dbbdb43 MD |
514 | static const struct file_operations lttng_metadata_fops = { |
515 | .release = lttng_channel_release, | |
516 | .unlocked_ioctl = lttng_metadata_ioctl, | |
517 | #ifdef CONFIG_COMPAT | |
518 | .compat_ioctl = lttng_metadata_ioctl, | |
519 | #endif | |
520 | }; | |
521 | ||
0a84a57f MD |
522 | static |
523 | int lttng_event_release(struct inode *inode, struct file *file) | |
524 | { | |
525 | struct ltt_event *event = file->private_data; | |
c269fff4 MD |
526 | |
527 | if (event) | |
528 | fput(event->chan->file); | |
0a84a57f MD |
529 | return 0; |
530 | } | |
531 | ||
3b923e5b | 532 | /* TODO: filter control ioctl */ |
0a84a57f MD |
533 | static const struct file_operations lttng_event_fops = { |
534 | .release = lttng_event_release, | |
11b5a3c2 | 535 | }; |
0a84a57f | 536 | |
1c25284c | 537 | int __init ltt_debugfs_abi_init(void) |
baf20995 MD |
538 | { |
539 | int ret = 0; | |
540 | ||
6d2a620c | 541 | wrapper_vmalloc_sync_all(); |
11b5a3c2 | 542 | lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL, |
f3d01b96 | 543 | <tng_fops); |
11b5a3c2 | 544 | if (IS_ERR(lttng_dentry) || !lttng_dentry) { |
baf20995 MD |
545 | printk(KERN_ERR "Error creating LTTng control file\n"); |
546 | ret = -ENOMEM; | |
547 | goto error; | |
548 | } | |
549 | error: | |
550 | return ret; | |
551 | } | |
552 | ||
1c25284c | 553 | void __exit ltt_debugfs_abi_exit(void) |
baf20995 | 554 | { |
11b5a3c2 | 555 | debugfs_remove(lttng_dentry); |
baf20995 | 556 | } |