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. | |
17baffe2 MD |
23 | * |
24 | * Dual LGPL v2.1/GPL v2 license. | |
baf20995 MD |
25 | */ |
26 | ||
11b5a3c2 | 27 | #include <linux/module.h> |
baf20995 | 28 | #include <linux/debugfs.h> |
e6a17f26 | 29 | #include <linux/proc_fs.h> |
11b5a3c2 MD |
30 | #include <linux/anon_inodes.h> |
31 | #include <linux/file.h> | |
32 | #include <linux/uaccess.h> | |
33 | #include <linux/slab.h> | |
b13f3ebe | 34 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
f3bc08c5 | 35 | #include "wrapper/ringbuffer/vfs.h" |
24cedcfe | 36 | #include "wrapper/poll.h" |
11b5a3c2 | 37 | #include "ltt-debugfs-abi.h" |
ad1c05e1 | 38 | #include "ltt-events.h" |
80c16bcf | 39 | #include "ltt-tracer.h" |
baf20995 MD |
40 | |
41 | /* | |
42 | * This is LTTng's own personal way to create a system call as an external | |
43 | * module. We use ioctl() on /sys/kernel/debug/lttng. | |
44 | */ | |
45 | ||
46 | static struct dentry *lttng_dentry; | |
e6a17f26 | 47 | static struct proc_dir_entry *lttng_proc_dentry; |
ad1c05e1 MD |
48 | static const struct file_operations lttng_fops; |
49 | static const struct file_operations lttng_session_fops; | |
50 | static const struct file_operations lttng_channel_fops; | |
5dbbdb43 | 51 | static const struct file_operations lttng_metadata_fops; |
305d3e42 | 52 | static const struct file_operations lttng_event_fops; |
baf20995 | 53 | |
a33c9927 MD |
54 | /* |
55 | * Teardown management: opened file descriptors keep a refcount on the module, | |
56 | * so it can only exit when all file descriptors are closed. | |
57 | */ | |
58 | ||
5dbbdb43 MD |
59 | enum channel_type { |
60 | PER_CPU_CHANNEL, | |
5dbbdb43 MD |
61 | METADATA_CHANNEL, |
62 | }; | |
63 | ||
ad1c05e1 | 64 | static |
baf20995 MD |
65 | int lttng_abi_create_session(void) |
66 | { | |
67 | struct ltt_session *session; | |
c0e31d2e | 68 | struct file *session_file; |
11b5a3c2 | 69 | int session_fd, ret; |
baf20995 | 70 | |
653fe716 | 71 | session = ltt_session_create(); |
baf20995 MD |
72 | if (!session) |
73 | return -ENOMEM; | |
1c25284c | 74 | session_fd = get_unused_fd(); |
baf20995 MD |
75 | if (session_fd < 0) { |
76 | ret = session_fd; | |
77 | goto fd_error; | |
78 | } | |
c0e31d2e | 79 | session_file = anon_inode_getfile("[lttng_session]", |
ad1c05e1 | 80 | <tng_session_fops, |
baf20995 | 81 | session, O_RDWR); |
c0e31d2e MD |
82 | if (IS_ERR(session_file)) { |
83 | ret = PTR_ERR(session_file); | |
baf20995 MD |
84 | goto file_error; |
85 | } | |
c0e31d2e MD |
86 | session->file = session_file; |
87 | fd_install(session_fd, session_file); | |
baf20995 MD |
88 | return session_fd; |
89 | ||
90 | file_error: | |
91 | put_unused_fd(session_fd); | |
92 | fd_error: | |
93 | ltt_session_destroy(session); | |
94 | return ret; | |
95 | } | |
96 | ||
271b6681 MD |
97 | static |
98 | int lttng_abi_tracepoint_list(void) | |
99 | { | |
100 | struct file *tracepoint_list_file; | |
101 | int file_fd, ret; | |
102 | ||
103 | file_fd = get_unused_fd(); | |
104 | if (file_fd < 0) { | |
105 | ret = file_fd; | |
106 | goto fd_error; | |
107 | } | |
30f18bf0 | 108 | |
271b6681 MD |
109 | tracepoint_list_file = anon_inode_getfile("[lttng_session]", |
110 | <tng_tracepoint_list_fops, | |
111 | NULL, O_RDWR); | |
112 | if (IS_ERR(tracepoint_list_file)) { | |
113 | ret = PTR_ERR(tracepoint_list_file); | |
114 | goto file_error; | |
115 | } | |
30f18bf0 MD |
116 | ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file); |
117 | if (ret < 0) | |
118 | goto open_error; | |
271b6681 | 119 | fd_install(file_fd, tracepoint_list_file); |
30f18bf0 MD |
120 | if (file_fd < 0) { |
121 | ret = file_fd; | |
122 | goto fd_error; | |
123 | } | |
271b6681 MD |
124 | return file_fd; |
125 | ||
30f18bf0 MD |
126 | open_error: |
127 | fput(tracepoint_list_file); | |
271b6681 MD |
128 | file_error: |
129 | put_unused_fd(file_fd); | |
130 | fd_error: | |
131 | return ret; | |
132 | } | |
133 | ||
80c16bcf MD |
134 | static |
135 | long lttng_abi_tracer_version(struct file *file, | |
136 | struct lttng_kernel_tracer_version __user *uversion_param) | |
137 | { | |
138 | struct lttng_kernel_tracer_version v; | |
139 | ||
140 | v.version = LTTNG_VERSION; | |
141 | v.patchlevel = LTTNG_PATCHLEVEL; | |
142 | v.sublevel = LTTNG_SUBLEVEL; | |
143 | ||
144 | if (copy_to_user(uversion_param, &v, sizeof(v))) | |
145 | return -EFAULT; | |
146 | return 0; | |
147 | } | |
148 | ||
8070f5c0 MD |
149 | static |
150 | long lttng_abi_add_context(struct file *file, | |
151 | struct lttng_kernel_context __user *ucontext_param, | |
152 | struct lttng_ctx **ctx, struct ltt_session *session) | |
153 | { | |
154 | struct lttng_kernel_context context_param; | |
155 | ||
156 | if (session->been_active) | |
157 | return -EPERM; | |
158 | ||
159 | if (copy_from_user(&context_param, ucontext_param, sizeof(context_param))) | |
160 | return -EFAULT; | |
161 | ||
162 | switch (context_param.ctx) { | |
12a313a5 | 163 | case LTTNG_KERNEL_CONTEXT_PID: |
8070f5c0 | 164 | return lttng_add_pid_to_ctx(ctx); |
a8ad3613 MD |
165 | case LTTNG_KERNEL_CONTEXT_PRIO: |
166 | return lttng_add_prio_to_ctx(ctx); | |
53f1f0ca MD |
167 | case LTTNG_KERNEL_CONTEXT_NICE: |
168 | return lttng_add_nice_to_ctx(ctx); | |
b64bc438 MD |
169 | case LTTNG_KERNEL_CONTEXT_VPID: |
170 | return lttng_add_vpid_to_ctx(ctx); | |
171 | case LTTNG_KERNEL_CONTEXT_TID: | |
172 | return lttng_add_tid_to_ctx(ctx); | |
173 | case LTTNG_KERNEL_CONTEXT_VTID: | |
174 | return lttng_add_vtid_to_ctx(ctx); | |
175 | case LTTNG_KERNEL_CONTEXT_PPID: | |
176 | return lttng_add_ppid_to_ctx(ctx); | |
177 | case LTTNG_KERNEL_CONTEXT_VPPID: | |
178 | return lttng_add_vppid_to_ctx(ctx); | |
12a313a5 | 179 | case LTTNG_KERNEL_CONTEXT_PERF_COUNTER: |
c24a0d71 MD |
180 | context_param.u.perf_counter.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
181 | return lttng_add_perf_counter_to_ctx(context_param.u.perf_counter.type, | |
182 | context_param.u.perf_counter.config, | |
183 | context_param.u.perf_counter.name, | |
184 | ctx); | |
25b2f99a MD |
185 | case LTTNG_KERNEL_CONTEXT_COMM: |
186 | return lttng_add_comm_to_ctx(ctx); | |
8070f5c0 MD |
187 | default: |
188 | return -EINVAL; | |
189 | } | |
190 | } | |
191 | ||
ad1c05e1 MD |
192 | /** |
193 | * lttng_ioctl - lttng syscall through ioctl | |
194 | * | |
c0e31d2e | 195 | * @file: the file |
ad1c05e1 MD |
196 | * @cmd: the command |
197 | * @arg: command arg | |
198 | * | |
199 | * This ioctl implements lttng commands: | |
38d024ae | 200 | * LTTNG_KERNEL_SESSION |
ad1c05e1 | 201 | * Returns a LTTng trace session file descriptor |
271b6681 MD |
202 | * LTTNG_KERNEL_TRACER_VERSION |
203 | * Returns the LTTng kernel tracer version | |
204 | * LTTNG_KERNEL_TRACEPOINT_LIST | |
205 | * Returns a file descriptor listing available tracepoints | |
360f38ea MD |
206 | * LTTNG_KERNEL_WAIT_QUIESCENT |
207 | * Returns after all previously running probes have completed | |
ad1c05e1 MD |
208 | * |
209 | * The returned session will be deleted when its file descriptor is closed. | |
210 | */ | |
211 | static | |
c0e31d2e | 212 | long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 MD |
213 | { |
214 | switch (cmd) { | |
38d024ae | 215 | case LTTNG_KERNEL_SESSION: |
ad1c05e1 | 216 | return lttng_abi_create_session(); |
80c16bcf MD |
217 | case LTTNG_KERNEL_TRACER_VERSION: |
218 | return lttng_abi_tracer_version(file, | |
219 | (struct lttng_kernel_tracer_version __user *) arg); | |
271b6681 MD |
220 | case LTTNG_KERNEL_TRACEPOINT_LIST: |
221 | return lttng_abi_tracepoint_list(); | |
5f7f9078 MD |
222 | case LTTNG_KERNEL_WAIT_QUIESCENT: |
223 | synchronize_trace(); | |
224 | return 0; | |
57105fc2 MD |
225 | case LTTNG_KERNEL_CALIBRATE: |
226 | { | |
3db41b2c MD |
227 | struct lttng_kernel_calibrate __user *ucalibrate = |
228 | (struct lttng_kernel_calibrate __user *) arg; | |
229 | struct lttng_kernel_calibrate calibrate; | |
57105fc2 MD |
230 | int ret; |
231 | ||
232 | if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate))) | |
233 | return -EFAULT; | |
234 | ret = lttng_calibrate(&calibrate); | |
235 | if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate))) | |
236 | return -EFAULT; | |
237 | return ret; | |
238 | } | |
ad1c05e1 MD |
239 | default: |
240 | return -ENOIOCTLCMD; | |
241 | } | |
242 | } | |
243 | ||
ad1c05e1 | 244 | static const struct file_operations lttng_fops = { |
a33c9927 | 245 | .owner = THIS_MODULE, |
ad1c05e1 MD |
246 | .unlocked_ioctl = lttng_ioctl, |
247 | #ifdef CONFIG_COMPAT | |
03037b98 | 248 | .compat_ioctl = lttng_ioctl, |
ad1c05e1 | 249 | #endif |
11b5a3c2 | 250 | }; |
ad1c05e1 | 251 | |
5dbbdb43 MD |
252 | /* |
253 | * We tolerate no failure in this function (if one happens, we print a dmesg | |
254 | * error, but cannot return any error, because the channel information is | |
255 | * invariant. | |
256 | */ | |
257 | static | |
258 | void lttng_metadata_create_events(struct file *channel_file) | |
259 | { | |
260 | struct ltt_channel *channel = channel_file->private_data; | |
e70a4758 | 261 | static struct lttng_kernel_event metadata_params = { |
ab2277d6 | 262 | .instrumentation = LTTNG_KERNEL_TRACEPOINT, |
e70a4758 MD |
263 | .name = "lttng_metadata", |
264 | }; | |
5dbbdb43 | 265 | struct ltt_event *event; |
5dbbdb43 | 266 | |
5dbbdb43 MD |
267 | /* |
268 | * We tolerate no failure path after event creation. It will stay | |
269 | * invariant for the rest of the session. | |
270 | */ | |
259b6cb3 | 271 | event = ltt_event_create(channel, &metadata_params, NULL, NULL); |
5dbbdb43 | 272 | if (!event) { |
271b6681 | 273 | goto create_error; |
5dbbdb43 MD |
274 | } |
275 | return; | |
276 | ||
85a9ca7f | 277 | create_error: |
5dbbdb43 MD |
278 | WARN_ON(1); |
279 | return; /* not allowed to return error */ | |
280 | } | |
281 | ||
282 | static | |
c0e31d2e | 283 | int lttng_abi_create_channel(struct file *session_file, |
38d024ae | 284 | struct lttng_kernel_channel __user *uchan_param, |
5dbbdb43 | 285 | enum channel_type channel_type) |
baf20995 | 286 | { |
c0e31d2e | 287 | struct ltt_session *session = session_file->private_data; |
88dfd899 | 288 | const struct file_operations *fops = NULL; |
5dbbdb43 | 289 | const char *transport_name; |
baf20995 | 290 | struct ltt_channel *chan; |
c0e31d2e | 291 | struct file *chan_file; |
38d024ae | 292 | struct lttng_kernel_channel chan_param; |
baf20995 | 293 | int chan_fd; |
ad1c05e1 | 294 | int ret = 0; |
baf20995 | 295 | |
653fe716 | 296 | if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param))) |
baf20995 | 297 | return -EFAULT; |
1c25284c | 298 | chan_fd = get_unused_fd(); |
baf20995 MD |
299 | if (chan_fd < 0) { |
300 | ret = chan_fd; | |
301 | goto fd_error; | |
302 | } | |
88dfd899 MD |
303 | switch (channel_type) { |
304 | case PER_CPU_CHANNEL: | |
305 | fops = <tng_channel_fops; | |
306 | break; | |
307 | case METADATA_CHANNEL: | |
308 | fops = <tng_metadata_fops; | |
309 | break; | |
310 | } | |
311 | ||
c0e31d2e | 312 | chan_file = anon_inode_getfile("[lttng_channel]", |
88dfd899 | 313 | fops, |
03037b98 | 314 | NULL, O_RDWR); |
c0e31d2e MD |
315 | if (IS_ERR(chan_file)) { |
316 | ret = PTR_ERR(chan_file); | |
baf20995 MD |
317 | goto file_error; |
318 | } | |
5dbbdb43 MD |
319 | switch (channel_type) { |
320 | case PER_CPU_CHANNEL: | |
96ba7208 JD |
321 | if (chan_param.output == LTTNG_KERNEL_SPLICE) { |
322 | transport_name = chan_param.overwrite ? | |
323 | "relay-overwrite" : "relay-discard"; | |
324 | } else if (chan_param.output == LTTNG_KERNEL_MMAP) { | |
325 | transport_name = chan_param.overwrite ? | |
326 | "relay-overwrite-mmap" : "relay-discard-mmap"; | |
327 | } else { | |
328 | return -EINVAL; | |
329 | } | |
5dbbdb43 | 330 | break; |
5dbbdb43 | 331 | case METADATA_CHANNEL: |
96ba7208 JD |
332 | if (chan_param.output == LTTNG_KERNEL_SPLICE) |
333 | transport_name = "relay-metadata"; | |
334 | else if (chan_param.output == LTTNG_KERNEL_MMAP) | |
335 | transport_name = "relay-metadata-mmap"; | |
336 | else | |
337 | return -EINVAL; | |
5dbbdb43 MD |
338 | break; |
339 | default: | |
340 | transport_name = "<unknown>"; | |
341 | break; | |
342 | } | |
03037b98 MD |
343 | /* |
344 | * We tolerate no failure path after channel creation. It will stay | |
345 | * invariant for the rest of the session. | |
346 | */ | |
5dbbdb43 | 347 | chan = ltt_channel_create(session, transport_name, NULL, |
11b5a3c2 MD |
348 | chan_param.subbuf_size, |
349 | chan_param.num_subbuf, | |
350 | chan_param.switch_timer_interval, | |
351 | chan_param.read_timer_interval); | |
03037b98 | 352 | if (!chan) { |
f3d01b96 | 353 | ret = -EINVAL; |
03037b98 MD |
354 | goto chan_error; |
355 | } | |
11b5a3c2 | 356 | chan->file = chan_file; |
c0e31d2e MD |
357 | chan_file->private_data = chan; |
358 | fd_install(chan_fd, chan_file); | |
cd4bd11f | 359 | if (channel_type == METADATA_CHANNEL) { |
cd4bd11f | 360 | session->metadata = chan; |
4f1c3952 | 361 | lttng_metadata_create_events(chan_file); |
cd4bd11f | 362 | } |
5dbbdb43 | 363 | |
ad1c05e1 | 364 | /* The channel created holds a reference on the session */ |
b0caa15a | 365 | atomic_long_inc(&session_file->f_count); |
ad1c05e1 | 366 | |
baf20995 MD |
367 | return chan_fd; |
368 | ||
03037b98 | 369 | chan_error: |
c0e31d2e | 370 | fput(chan_file); |
baf20995 MD |
371 | file_error: |
372 | put_unused_fd(chan_fd); | |
373 | fd_error: | |
baf20995 MD |
374 | return ret; |
375 | } | |
376 | ||
377 | /** | |
ad1c05e1 | 378 | * lttng_session_ioctl - lttng session fd ioctl |
baf20995 | 379 | * |
c0e31d2e | 380 | * @file: the file |
baf20995 MD |
381 | * @cmd: the command |
382 | * @arg: command arg | |
383 | * | |
384 | * This ioctl implements lttng commands: | |
38d024ae | 385 | * LTTNG_KERNEL_CHANNEL |
baf20995 | 386 | * Returns a LTTng channel file descriptor |
e64957da MD |
387 | * LTTNG_KERNEL_ENABLE |
388 | * Enables tracing for a session (weak enable) | |
389 | * LTTNG_KERNEL_DISABLE | |
390 | * Disables tracing for a session (strong disable) | |
8070f5c0 MD |
391 | * LTTNG_KERNEL_METADATA |
392 | * Returns a LTTng metadata file descriptor | |
ad1c05e1 MD |
393 | * |
394 | * The returned channel will be deleted when its file descriptor is closed. | |
395 | */ | |
396 | static | |
c0e31d2e | 397 | long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 | 398 | { |
c0e31d2e MD |
399 | struct ltt_session *session = file->private_data; |
400 | ||
ad1c05e1 | 401 | switch (cmd) { |
38d024ae | 402 | case LTTNG_KERNEL_CHANNEL: |
5dbbdb43 | 403 | return lttng_abi_create_channel(file, |
38d024ae | 404 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 405 | PER_CPU_CHANNEL); |
38d024ae | 406 | case LTTNG_KERNEL_SESSION_START: |
e64957da MD |
407 | case LTTNG_KERNEL_ENABLE: |
408 | return ltt_session_enable(session); | |
38d024ae | 409 | case LTTNG_KERNEL_SESSION_STOP: |
e64957da MD |
410 | case LTTNG_KERNEL_DISABLE: |
411 | return ltt_session_disable(session); | |
38d024ae | 412 | case LTTNG_KERNEL_METADATA: |
5dbbdb43 | 413 | return lttng_abi_create_channel(file, |
38d024ae | 414 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 415 | METADATA_CHANNEL); |
ad1c05e1 MD |
416 | default: |
417 | return -ENOIOCTLCMD; | |
418 | } | |
419 | } | |
420 | ||
03037b98 MD |
421 | /* |
422 | * Called when the last file reference is dropped. | |
423 | * | |
424 | * Big fat note: channels and events are invariant for the whole session after | |
425 | * their creation. So this session destruction also destroys all channel and | |
426 | * event structures specific to this session (they are not destroyed when their | |
427 | * individual file is released). | |
428 | */ | |
ad1c05e1 | 429 | static |
03037b98 | 430 | int lttng_session_release(struct inode *inode, struct file *file) |
ad1c05e1 | 431 | { |
03037b98 | 432 | struct ltt_session *session = file->private_data; |
c269fff4 MD |
433 | |
434 | if (session) | |
435 | ltt_session_destroy(session); | |
11b5a3c2 | 436 | return 0; |
ad1c05e1 | 437 | } |
ad1c05e1 MD |
438 | |
439 | static const struct file_operations lttng_session_fops = { | |
a33c9927 | 440 | .owner = THIS_MODULE, |
03037b98 | 441 | .release = lttng_session_release, |
ad1c05e1 MD |
442 | .unlocked_ioctl = lttng_session_ioctl, |
443 | #ifdef CONFIG_COMPAT | |
03037b98 | 444 | .compat_ioctl = lttng_session_ioctl, |
ad1c05e1 | 445 | #endif |
11b5a3c2 | 446 | }; |
ad1c05e1 MD |
447 | |
448 | static | |
c0e31d2e | 449 | int lttng_abi_open_stream(struct file *channel_file) |
ad1c05e1 | 450 | { |
c0e31d2e | 451 | struct ltt_channel *channel = channel_file->private_data; |
ad1c05e1 MD |
452 | struct lib_ring_buffer *buf; |
453 | int stream_fd, ret; | |
11b5a3c2 | 454 | struct file *stream_file; |
ad1c05e1 | 455 | |
11b5a3c2 | 456 | buf = channel->ops->buffer_read_open(channel->chan); |
ad1c05e1 MD |
457 | if (!buf) |
458 | return -ENOENT; | |
459 | ||
1c25284c | 460 | stream_fd = get_unused_fd(); |
ad1c05e1 MD |
461 | if (stream_fd < 0) { |
462 | ret = stream_fd; | |
463 | goto fd_error; | |
464 | } | |
c0e31d2e | 465 | stream_file = anon_inode_getfile("[lttng_stream]", |
7f57c73c | 466 | &lib_ring_buffer_file_operations, |
ad1c05e1 | 467 | buf, O_RDWR); |
c0e31d2e MD |
468 | if (IS_ERR(stream_file)) { |
469 | ret = PTR_ERR(stream_file); | |
ad1c05e1 MD |
470 | goto file_error; |
471 | } | |
409453cb MD |
472 | /* |
473 | * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor | |
474 | * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this | |
475 | * file descriptor, so we set FMODE_PREAD here. | |
476 | */ | |
d7b6f197 | 477 | stream_file->f_mode |= FMODE_PREAD; |
c0e31d2e | 478 | fd_install(stream_fd, stream_file); |
dda6a249 MD |
479 | /* |
480 | * The stream holds a reference to the channel within the generic ring | |
481 | * buffer library, so no need to hold a refcount on the channel and | |
482 | * session files here. | |
483 | */ | |
ad1c05e1 MD |
484 | return stream_fd; |
485 | ||
486 | file_error: | |
487 | put_unused_fd(stream_fd); | |
488 | fd_error: | |
11b5a3c2 | 489 | channel->ops->buffer_read_close(buf); |
ad1c05e1 MD |
490 | return ret; |
491 | } | |
492 | ||
653fe716 | 493 | static |
c0e31d2e | 494 | int lttng_abi_create_event(struct file *channel_file, |
38d024ae | 495 | struct lttng_kernel_event __user *uevent_param) |
653fe716 | 496 | { |
c0e31d2e | 497 | struct ltt_channel *channel = channel_file->private_data; |
653fe716 | 498 | struct ltt_event *event; |
38d024ae | 499 | struct lttng_kernel_event event_param; |
653fe716 | 500 | int event_fd, ret; |
11b5a3c2 | 501 | struct file *event_file; |
653fe716 MD |
502 | |
503 | if (copy_from_user(&event_param, uevent_param, sizeof(event_param))) | |
504 | return -EFAULT; | |
30bdb6e4 | 505 | event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
e0a7a7c4 | 506 | switch (event_param.instrumentation) { |
7371f44c MD |
507 | case LTTNG_KERNEL_KRETPROBE: |
508 | event_param.u.kretprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; | |
509 | break; | |
ab2277d6 | 510 | case LTTNG_KERNEL_KPROBE: |
e0a7a7c4 MD |
511 | event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
512 | break; | |
ab2277d6 | 513 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
514 | event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
515 | break; | |
516 | default: | |
517 | break; | |
518 | } | |
1ec65de1 MD |
519 | switch (event_param.instrumentation) { |
520 | default: | |
521 | event_fd = get_unused_fd(); | |
522 | if (event_fd < 0) { | |
523 | ret = event_fd; | |
524 | goto fd_error; | |
525 | } | |
526 | event_file = anon_inode_getfile("[lttng_event]", | |
527 | <tng_event_fops, | |
528 | NULL, O_RDWR); | |
529 | if (IS_ERR(event_file)) { | |
530 | ret = PTR_ERR(event_file); | |
531 | goto file_error; | |
532 | } | |
533 | /* | |
534 | * We tolerate no failure path after event creation. It | |
535 | * will stay invariant for the rest of the session. | |
536 | */ | |
259b6cb3 | 537 | event = ltt_event_create(channel, &event_param, NULL, NULL); |
1ec65de1 MD |
538 | if (!event) { |
539 | ret = -EINVAL; | |
540 | goto event_error; | |
541 | } | |
542 | event_file->private_data = event; | |
543 | fd_install(event_fd, event_file); | |
544 | /* The event holds a reference on the channel */ | |
545 | atomic_long_inc(&channel_file->f_count); | |
546 | break; | |
547 | case LTTNG_KERNEL_SYSCALLS: | |
548 | ret = lttng_syscalls_register(channel, NULL); | |
549 | if (ret) | |
550 | goto fd_error; | |
551 | event_fd = 0; | |
552 | break; | |
03037b98 | 553 | } |
653fe716 MD |
554 | return event_fd; |
555 | ||
03037b98 | 556 | event_error: |
c0e31d2e | 557 | fput(event_file); |
653fe716 MD |
558 | file_error: |
559 | put_unused_fd(event_fd); | |
560 | fd_error: | |
653fe716 MD |
561 | return ret; |
562 | } | |
ad1c05e1 MD |
563 | |
564 | /** | |
565 | * lttng_channel_ioctl - lttng syscall through ioctl | |
566 | * | |
c0e31d2e | 567 | * @file: the file |
ad1c05e1 MD |
568 | * @cmd: the command |
569 | * @arg: command arg | |
570 | * | |
571 | * This ioctl implements lttng commands: | |
38d024ae | 572 | * LTTNG_KERNEL_STREAM |
ad1c05e1 MD |
573 | * Returns an event stream file descriptor or failure. |
574 | * (typically, one event stream records events from one CPU) | |
38d024ae | 575 | * LTTNG_KERNEL_EVENT |
ad1c05e1 | 576 | * Returns an event file descriptor or failure. |
8070f5c0 MD |
577 | * LTTNG_KERNEL_CONTEXT |
578 | * Prepend a context field to each event in the channel | |
e64957da MD |
579 | * LTTNG_KERNEL_ENABLE |
580 | * Enable recording for events in this channel (weak enable) | |
581 | * LTTNG_KERNEL_DISABLE | |
582 | * Disable recording for events in this channel (strong disable) | |
baf20995 | 583 | * |
baf20995 MD |
584 | * Channel and event file descriptors also hold a reference on the session. |
585 | */ | |
ad1c05e1 | 586 | static |
c0e31d2e | 587 | long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
baf20995 | 588 | { |
8070f5c0 MD |
589 | struct ltt_channel *channel = file->private_data; |
590 | ||
baf20995 | 591 | switch (cmd) { |
38d024ae | 592 | case LTTNG_KERNEL_STREAM: |
c0e31d2e | 593 | return lttng_abi_open_stream(file); |
38d024ae MD |
594 | case LTTNG_KERNEL_EVENT: |
595 | return lttng_abi_create_event(file, (struct lttng_kernel_event __user *) arg); | |
8070f5c0 MD |
596 | case LTTNG_KERNEL_CONTEXT: |
597 | return lttng_abi_add_context(file, | |
598 | (struct lttng_kernel_context __user *) arg, | |
599 | &channel->ctx, channel->session); | |
e64957da MD |
600 | case LTTNG_KERNEL_ENABLE: |
601 | return ltt_channel_enable(channel); | |
602 | case LTTNG_KERNEL_DISABLE: | |
603 | return ltt_channel_disable(channel); | |
baf20995 MD |
604 | default: |
605 | return -ENOIOCTLCMD; | |
606 | } | |
607 | } | |
608 | ||
5dbbdb43 MD |
609 | /** |
610 | * lttng_metadata_ioctl - lttng syscall through ioctl | |
611 | * | |
612 | * @file: the file | |
613 | * @cmd: the command | |
614 | * @arg: command arg | |
615 | * | |
616 | * This ioctl implements lttng commands: | |
38d024ae | 617 | * LTTNG_KERNEL_STREAM |
5dbbdb43 MD |
618 | * Returns an event stream file descriptor or failure. |
619 | * | |
620 | * Channel and event file descriptors also hold a reference on the session. | |
621 | */ | |
622 | static | |
623 | long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
624 | { | |
625 | switch (cmd) { | |
38d024ae | 626 | case LTTNG_KERNEL_STREAM: |
5dbbdb43 MD |
627 | return lttng_abi_open_stream(file); |
628 | default: | |
629 | return -ENOIOCTLCMD; | |
630 | } | |
631 | } | |
632 | ||
653fe716 MD |
633 | /** |
634 | * lttng_channel_poll - lttng stream addition/removal monitoring | |
635 | * | |
c0e31d2e | 636 | * @file: the file |
653fe716 MD |
637 | * @wait: poll table |
638 | */ | |
c0e31d2e | 639 | unsigned int lttng_channel_poll(struct file *file, poll_table *wait) |
653fe716 | 640 | { |
c0e31d2e | 641 | struct ltt_channel *channel = file->private_data; |
653fe716 MD |
642 | unsigned int mask = 0; |
643 | ||
c0e31d2e | 644 | if (file->f_mode & FMODE_READ) { |
a33e44a6 | 645 | poll_wait_set_exclusive(wait); |
24cedcfe MD |
646 | poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan), |
647 | wait); | |
653fe716 | 648 | |
254ec7bc MD |
649 | if (channel->ops->is_disabled(channel->chan)) |
650 | return POLLERR; | |
24cedcfe | 651 | if (channel->ops->is_finalized(channel->chan)) |
653fe716 | 652 | return POLLHUP; |
f71ecafa | 653 | if (channel->ops->buffer_has_read_closed_stream(channel->chan)) |
653fe716 | 654 | return POLLIN | POLLRDNORM; |
f71ecafa | 655 | return 0; |
653fe716 MD |
656 | } |
657 | return mask; | |
658 | ||
659 | } | |
660 | ||
0a84a57f MD |
661 | static |
662 | int lttng_channel_release(struct inode *inode, struct file *file) | |
663 | { | |
664 | struct ltt_channel *channel = file->private_data; | |
c269fff4 MD |
665 | |
666 | if (channel) | |
667 | fput(channel->session->file); | |
0a84a57f MD |
668 | return 0; |
669 | } | |
670 | ||
ad1c05e1 | 671 | static const struct file_operations lttng_channel_fops = { |
a33c9927 | 672 | .owner = THIS_MODULE, |
03037b98 | 673 | .release = lttng_channel_release, |
653fe716 | 674 | .poll = lttng_channel_poll, |
ad1c05e1 | 675 | .unlocked_ioctl = lttng_channel_ioctl, |
baf20995 | 676 | #ifdef CONFIG_COMPAT |
03037b98 | 677 | .compat_ioctl = lttng_channel_ioctl, |
baf20995 | 678 | #endif |
11b5a3c2 | 679 | }; |
baf20995 | 680 | |
5dbbdb43 | 681 | static const struct file_operations lttng_metadata_fops = { |
a33c9927 | 682 | .owner = THIS_MODULE, |
5dbbdb43 MD |
683 | .release = lttng_channel_release, |
684 | .unlocked_ioctl = lttng_metadata_ioctl, | |
685 | #ifdef CONFIG_COMPAT | |
686 | .compat_ioctl = lttng_metadata_ioctl, | |
687 | #endif | |
688 | }; | |
689 | ||
8070f5c0 MD |
690 | /** |
691 | * lttng_event_ioctl - lttng syscall through ioctl | |
692 | * | |
693 | * @file: the file | |
694 | * @cmd: the command | |
695 | * @arg: command arg | |
696 | * | |
697 | * This ioctl implements lttng commands: | |
8070f5c0 MD |
698 | * LTTNG_KERNEL_CONTEXT |
699 | * Prepend a context field to each record of this event | |
e64957da MD |
700 | * LTTNG_KERNEL_ENABLE |
701 | * Enable recording for this event (weak enable) | |
702 | * LTTNG_KERNEL_DISABLE | |
703 | * Disable recording for this event (strong disable) | |
8070f5c0 MD |
704 | */ |
705 | static | |
706 | long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
707 | { | |
708 | struct ltt_event *event = file->private_data; | |
709 | ||
710 | switch (cmd) { | |
711 | case LTTNG_KERNEL_CONTEXT: | |
712 | return lttng_abi_add_context(file, | |
713 | (struct lttng_kernel_context __user *) arg, | |
714 | &event->ctx, event->chan->session); | |
e64957da MD |
715 | case LTTNG_KERNEL_ENABLE: |
716 | return ltt_event_enable(event); | |
717 | case LTTNG_KERNEL_DISABLE: | |
718 | return ltt_event_disable(event); | |
8070f5c0 MD |
719 | default: |
720 | return -ENOIOCTLCMD; | |
721 | } | |
722 | } | |
723 | ||
0a84a57f MD |
724 | static |
725 | int lttng_event_release(struct inode *inode, struct file *file) | |
726 | { | |
727 | struct ltt_event *event = file->private_data; | |
c269fff4 | 728 | |
aa7c23a9 | 729 | if (event) |
c269fff4 | 730 | fput(event->chan->file); |
0a84a57f MD |
731 | return 0; |
732 | } | |
733 | ||
3b923e5b | 734 | /* TODO: filter control ioctl */ |
0a84a57f | 735 | static const struct file_operations lttng_event_fops = { |
a33c9927 | 736 | .owner = THIS_MODULE, |
0a84a57f | 737 | .release = lttng_event_release, |
8070f5c0 MD |
738 | .unlocked_ioctl = lttng_event_ioctl, |
739 | #ifdef CONFIG_COMPAT | |
740 | .compat_ioctl = lttng_event_ioctl, | |
741 | #endif | |
11b5a3c2 | 742 | }; |
0a84a57f | 743 | |
1c25284c | 744 | int __init ltt_debugfs_abi_init(void) |
baf20995 MD |
745 | { |
746 | int ret = 0; | |
747 | ||
6d2a620c | 748 | wrapper_vmalloc_sync_all(); |
11b5a3c2 | 749 | lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL, |
e6a17f26 MD |
750 | <tng_fops); |
751 | if (IS_ERR(lttng_dentry)) | |
752 | lttng_dentry = NULL; | |
753 | ||
754 | lttng_proc_dentry = proc_create_data("lttng", S_IWUSR, NULL, | |
755 | <tng_fops, NULL); | |
756 | ||
757 | if (!lttng_dentry && !lttng_proc_dentry) { | |
baf20995 MD |
758 | printk(KERN_ERR "Error creating LTTng control file\n"); |
759 | ret = -ENOMEM; | |
760 | goto error; | |
761 | } | |
762 | error: | |
763 | return ret; | |
764 | } | |
765 | ||
1c25284c | 766 | void __exit ltt_debugfs_abi_exit(void) |
baf20995 | 767 | { |
e6a17f26 MD |
768 | if (lttng_dentry) |
769 | debugfs_remove(lttng_dentry); | |
770 | if (lttng_proc_dentry) | |
771 | remove_proc_entry("lttng", NULL); | |
baf20995 | 772 | } |