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> |
11b5a3c2 MD |
29 | #include <linux/anon_inodes.h> |
30 | #include <linux/file.h> | |
31 | #include <linux/uaccess.h> | |
32 | #include <linux/slab.h> | |
b13f3ebe | 33 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
f3bc08c5 | 34 | #include "wrapper/ringbuffer/vfs.h" |
24cedcfe | 35 | #include "wrapper/poll.h" |
11b5a3c2 | 36 | #include "ltt-debugfs-abi.h" |
ad1c05e1 | 37 | #include "ltt-events.h" |
80c16bcf | 38 | #include "ltt-tracer.h" |
baf20995 MD |
39 | |
40 | /* | |
41 | * This is LTTng's own personal way to create a system call as an external | |
42 | * module. We use ioctl() on /sys/kernel/debug/lttng. | |
43 | */ | |
44 | ||
45 | static struct dentry *lttng_dentry; | |
ad1c05e1 MD |
46 | static const struct file_operations lttng_fops; |
47 | static const struct file_operations lttng_session_fops; | |
48 | static const struct file_operations lttng_channel_fops; | |
5dbbdb43 | 49 | static const struct file_operations lttng_metadata_fops; |
305d3e42 | 50 | static const struct file_operations lttng_event_fops; |
baf20995 | 51 | |
5dbbdb43 MD |
52 | enum channel_type { |
53 | PER_CPU_CHANNEL, | |
5dbbdb43 MD |
54 | METADATA_CHANNEL, |
55 | }; | |
56 | ||
ad1c05e1 | 57 | static |
baf20995 MD |
58 | int lttng_abi_create_session(void) |
59 | { | |
60 | struct ltt_session *session; | |
c0e31d2e | 61 | struct file *session_file; |
11b5a3c2 | 62 | int session_fd, ret; |
baf20995 | 63 | |
653fe716 | 64 | session = ltt_session_create(); |
baf20995 MD |
65 | if (!session) |
66 | return -ENOMEM; | |
1c25284c | 67 | session_fd = get_unused_fd(); |
baf20995 MD |
68 | if (session_fd < 0) { |
69 | ret = session_fd; | |
70 | goto fd_error; | |
71 | } | |
c0e31d2e | 72 | session_file = anon_inode_getfile("[lttng_session]", |
ad1c05e1 | 73 | <tng_session_fops, |
baf20995 | 74 | session, O_RDWR); |
c0e31d2e MD |
75 | if (IS_ERR(session_file)) { |
76 | ret = PTR_ERR(session_file); | |
baf20995 MD |
77 | goto file_error; |
78 | } | |
c0e31d2e MD |
79 | session->file = session_file; |
80 | fd_install(session_fd, session_file); | |
baf20995 MD |
81 | return session_fd; |
82 | ||
83 | file_error: | |
84 | put_unused_fd(session_fd); | |
85 | fd_error: | |
86 | ltt_session_destroy(session); | |
87 | return ret; | |
88 | } | |
89 | ||
271b6681 MD |
90 | static |
91 | int lttng_abi_tracepoint_list(void) | |
92 | { | |
93 | struct file *tracepoint_list_file; | |
94 | int file_fd, ret; | |
95 | ||
96 | file_fd = get_unused_fd(); | |
97 | if (file_fd < 0) { | |
98 | ret = file_fd; | |
99 | goto fd_error; | |
100 | } | |
30f18bf0 | 101 | |
271b6681 MD |
102 | tracepoint_list_file = anon_inode_getfile("[lttng_session]", |
103 | <tng_tracepoint_list_fops, | |
104 | NULL, O_RDWR); | |
105 | if (IS_ERR(tracepoint_list_file)) { | |
106 | ret = PTR_ERR(tracepoint_list_file); | |
107 | goto file_error; | |
108 | } | |
30f18bf0 MD |
109 | ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file); |
110 | if (ret < 0) | |
111 | goto open_error; | |
271b6681 | 112 | fd_install(file_fd, tracepoint_list_file); |
30f18bf0 MD |
113 | if (file_fd < 0) { |
114 | ret = file_fd; | |
115 | goto fd_error; | |
116 | } | |
271b6681 MD |
117 | return file_fd; |
118 | ||
30f18bf0 MD |
119 | open_error: |
120 | fput(tracepoint_list_file); | |
271b6681 MD |
121 | file_error: |
122 | put_unused_fd(file_fd); | |
123 | fd_error: | |
124 | return ret; | |
125 | } | |
126 | ||
80c16bcf MD |
127 | static |
128 | long lttng_abi_tracer_version(struct file *file, | |
129 | struct lttng_kernel_tracer_version __user *uversion_param) | |
130 | { | |
131 | struct lttng_kernel_tracer_version v; | |
132 | ||
133 | v.version = LTTNG_VERSION; | |
134 | v.patchlevel = LTTNG_PATCHLEVEL; | |
135 | v.sublevel = LTTNG_SUBLEVEL; | |
136 | ||
137 | if (copy_to_user(uversion_param, &v, sizeof(v))) | |
138 | return -EFAULT; | |
139 | return 0; | |
140 | } | |
141 | ||
8070f5c0 MD |
142 | static |
143 | long lttng_abi_add_context(struct file *file, | |
144 | struct lttng_kernel_context __user *ucontext_param, | |
145 | struct lttng_ctx **ctx, struct ltt_session *session) | |
146 | { | |
147 | struct lttng_kernel_context context_param; | |
148 | ||
149 | if (session->been_active) | |
150 | return -EPERM; | |
151 | ||
152 | if (copy_from_user(&context_param, ucontext_param, sizeof(context_param))) | |
153 | return -EFAULT; | |
154 | ||
155 | switch (context_param.ctx) { | |
12a313a5 | 156 | case LTTNG_KERNEL_CONTEXT_PID: |
8070f5c0 | 157 | return lttng_add_pid_to_ctx(ctx); |
a8ad3613 MD |
158 | case LTTNG_KERNEL_CONTEXT_PRIO: |
159 | return lttng_add_prio_to_ctx(ctx); | |
53f1f0ca MD |
160 | case LTTNG_KERNEL_CONTEXT_NICE: |
161 | return lttng_add_nice_to_ctx(ctx); | |
b64bc438 MD |
162 | case LTTNG_KERNEL_CONTEXT_VPID: |
163 | return lttng_add_vpid_to_ctx(ctx); | |
164 | case LTTNG_KERNEL_CONTEXT_TID: | |
165 | return lttng_add_tid_to_ctx(ctx); | |
166 | case LTTNG_KERNEL_CONTEXT_VTID: | |
167 | return lttng_add_vtid_to_ctx(ctx); | |
168 | case LTTNG_KERNEL_CONTEXT_PPID: | |
169 | return lttng_add_ppid_to_ctx(ctx); | |
170 | case LTTNG_KERNEL_CONTEXT_VPPID: | |
171 | return lttng_add_vppid_to_ctx(ctx); | |
12a313a5 | 172 | case LTTNG_KERNEL_CONTEXT_PERF_COUNTER: |
c24a0d71 MD |
173 | context_param.u.perf_counter.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
174 | return lttng_add_perf_counter_to_ctx(context_param.u.perf_counter.type, | |
175 | context_param.u.perf_counter.config, | |
176 | context_param.u.perf_counter.name, | |
177 | ctx); | |
25b2f99a MD |
178 | case LTTNG_KERNEL_CONTEXT_COMM: |
179 | return lttng_add_comm_to_ctx(ctx); | |
8070f5c0 MD |
180 | default: |
181 | return -EINVAL; | |
182 | } | |
183 | } | |
184 | ||
ad1c05e1 MD |
185 | /** |
186 | * lttng_ioctl - lttng syscall through ioctl | |
187 | * | |
c0e31d2e | 188 | * @file: the file |
ad1c05e1 MD |
189 | * @cmd: the command |
190 | * @arg: command arg | |
191 | * | |
192 | * This ioctl implements lttng commands: | |
38d024ae | 193 | * LTTNG_KERNEL_SESSION |
ad1c05e1 | 194 | * Returns a LTTng trace session file descriptor |
271b6681 MD |
195 | * LTTNG_KERNEL_TRACER_VERSION |
196 | * Returns the LTTng kernel tracer version | |
197 | * LTTNG_KERNEL_TRACEPOINT_LIST | |
198 | * Returns a file descriptor listing available tracepoints | |
360f38ea MD |
199 | * LTTNG_KERNEL_WAIT_QUIESCENT |
200 | * Returns after all previously running probes have completed | |
ad1c05e1 MD |
201 | * |
202 | * The returned session will be deleted when its file descriptor is closed. | |
203 | */ | |
204 | static | |
c0e31d2e | 205 | long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 MD |
206 | { |
207 | switch (cmd) { | |
38d024ae | 208 | case LTTNG_KERNEL_SESSION: |
ad1c05e1 | 209 | return lttng_abi_create_session(); |
80c16bcf MD |
210 | case LTTNG_KERNEL_TRACER_VERSION: |
211 | return lttng_abi_tracer_version(file, | |
212 | (struct lttng_kernel_tracer_version __user *) arg); | |
271b6681 MD |
213 | case LTTNG_KERNEL_TRACEPOINT_LIST: |
214 | return lttng_abi_tracepoint_list(); | |
5f7f9078 MD |
215 | case LTTNG_KERNEL_WAIT_QUIESCENT: |
216 | synchronize_trace(); | |
217 | return 0; | |
ad1c05e1 MD |
218 | default: |
219 | return -ENOIOCTLCMD; | |
220 | } | |
221 | } | |
222 | ||
ad1c05e1 MD |
223 | static const struct file_operations lttng_fops = { |
224 | .unlocked_ioctl = lttng_ioctl, | |
225 | #ifdef CONFIG_COMPAT | |
03037b98 | 226 | .compat_ioctl = lttng_ioctl, |
ad1c05e1 | 227 | #endif |
11b5a3c2 | 228 | }; |
ad1c05e1 | 229 | |
5dbbdb43 MD |
230 | /* |
231 | * We tolerate no failure in this function (if one happens, we print a dmesg | |
232 | * error, but cannot return any error, because the channel information is | |
233 | * invariant. | |
234 | */ | |
235 | static | |
236 | void lttng_metadata_create_events(struct file *channel_file) | |
237 | { | |
238 | struct ltt_channel *channel = channel_file->private_data; | |
e70a4758 | 239 | static struct lttng_kernel_event metadata_params = { |
ab2277d6 | 240 | .instrumentation = LTTNG_KERNEL_TRACEPOINT, |
e70a4758 MD |
241 | .name = "lttng_metadata", |
242 | }; | |
5dbbdb43 MD |
243 | struct ltt_event *event; |
244 | int ret; | |
5dbbdb43 | 245 | |
5dbbdb43 MD |
246 | /* |
247 | * We tolerate no failure path after event creation. It will stay | |
248 | * invariant for the rest of the session. | |
249 | */ | |
30bdb6e4 | 250 | event = ltt_event_create(channel, &metadata_params, NULL); |
5dbbdb43 | 251 | if (!event) { |
588e6a7f | 252 | ret = -EINVAL; |
271b6681 | 253 | goto create_error; |
5dbbdb43 MD |
254 | } |
255 | return; | |
256 | ||
85a9ca7f | 257 | create_error: |
5dbbdb43 MD |
258 | WARN_ON(1); |
259 | return; /* not allowed to return error */ | |
260 | } | |
261 | ||
262 | static | |
c0e31d2e | 263 | int lttng_abi_create_channel(struct file *session_file, |
38d024ae | 264 | struct lttng_kernel_channel __user *uchan_param, |
5dbbdb43 | 265 | enum channel_type channel_type) |
baf20995 | 266 | { |
c0e31d2e | 267 | struct ltt_session *session = session_file->private_data; |
5dbbdb43 MD |
268 | const struct file_operations *fops; |
269 | const char *transport_name; | |
baf20995 | 270 | struct ltt_channel *chan; |
c0e31d2e | 271 | struct file *chan_file; |
38d024ae | 272 | struct lttng_kernel_channel chan_param; |
baf20995 | 273 | int chan_fd; |
ad1c05e1 | 274 | int ret = 0; |
baf20995 | 275 | |
653fe716 | 276 | if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param))) |
baf20995 | 277 | return -EFAULT; |
1c25284c | 278 | chan_fd = get_unused_fd(); |
baf20995 MD |
279 | if (chan_fd < 0) { |
280 | ret = chan_fd; | |
281 | goto fd_error; | |
282 | } | |
c0e31d2e | 283 | chan_file = anon_inode_getfile("[lttng_channel]", |
ad1c05e1 | 284 | <tng_channel_fops, |
03037b98 | 285 | NULL, O_RDWR); |
c0e31d2e MD |
286 | if (IS_ERR(chan_file)) { |
287 | ret = PTR_ERR(chan_file); | |
baf20995 MD |
288 | goto file_error; |
289 | } | |
5dbbdb43 MD |
290 | switch (channel_type) { |
291 | case PER_CPU_CHANNEL: | |
96ba7208 JD |
292 | if (chan_param.output == LTTNG_KERNEL_SPLICE) { |
293 | transport_name = chan_param.overwrite ? | |
294 | "relay-overwrite" : "relay-discard"; | |
295 | } else if (chan_param.output == LTTNG_KERNEL_MMAP) { | |
296 | transport_name = chan_param.overwrite ? | |
297 | "relay-overwrite-mmap" : "relay-discard-mmap"; | |
298 | } else { | |
299 | return -EINVAL; | |
300 | } | |
5dbbdb43 MD |
301 | fops = <tng_channel_fops; |
302 | break; | |
5dbbdb43 | 303 | case METADATA_CHANNEL: |
96ba7208 JD |
304 | if (chan_param.output == LTTNG_KERNEL_SPLICE) |
305 | transport_name = "relay-metadata"; | |
306 | else if (chan_param.output == LTTNG_KERNEL_MMAP) | |
307 | transport_name = "relay-metadata-mmap"; | |
308 | else | |
309 | return -EINVAL; | |
5dbbdb43 MD |
310 | fops = <tng_metadata_fops; |
311 | break; | |
312 | default: | |
313 | transport_name = "<unknown>"; | |
314 | break; | |
315 | } | |
03037b98 MD |
316 | /* |
317 | * We tolerate no failure path after channel creation. It will stay | |
318 | * invariant for the rest of the session. | |
319 | */ | |
5dbbdb43 | 320 | chan = ltt_channel_create(session, transport_name, NULL, |
11b5a3c2 MD |
321 | chan_param.subbuf_size, |
322 | chan_param.num_subbuf, | |
323 | chan_param.switch_timer_interval, | |
324 | chan_param.read_timer_interval); | |
03037b98 | 325 | if (!chan) { |
f3d01b96 | 326 | ret = -EINVAL; |
03037b98 MD |
327 | goto chan_error; |
328 | } | |
11b5a3c2 | 329 | chan->file = chan_file; |
c0e31d2e MD |
330 | chan_file->private_data = chan; |
331 | fd_install(chan_fd, chan_file); | |
cd4bd11f | 332 | if (channel_type == METADATA_CHANNEL) { |
cd4bd11f | 333 | session->metadata = chan; |
4f1c3952 | 334 | lttng_metadata_create_events(chan_file); |
cd4bd11f | 335 | } |
5dbbdb43 | 336 | |
ad1c05e1 | 337 | /* The channel created holds a reference on the session */ |
b0caa15a | 338 | atomic_long_inc(&session_file->f_count); |
ad1c05e1 | 339 | |
baf20995 MD |
340 | return chan_fd; |
341 | ||
03037b98 | 342 | chan_error: |
c0e31d2e | 343 | fput(chan_file); |
baf20995 MD |
344 | file_error: |
345 | put_unused_fd(chan_fd); | |
346 | fd_error: | |
baf20995 MD |
347 | return ret; |
348 | } | |
349 | ||
350 | /** | |
ad1c05e1 | 351 | * lttng_session_ioctl - lttng session fd ioctl |
baf20995 | 352 | * |
c0e31d2e | 353 | * @file: the file |
baf20995 MD |
354 | * @cmd: the command |
355 | * @arg: command arg | |
356 | * | |
357 | * This ioctl implements lttng commands: | |
38d024ae | 358 | * LTTNG_KERNEL_CHANNEL |
baf20995 | 359 | * Returns a LTTng channel file descriptor |
e64957da MD |
360 | * LTTNG_KERNEL_ENABLE |
361 | * Enables tracing for a session (weak enable) | |
362 | * LTTNG_KERNEL_DISABLE | |
363 | * Disables tracing for a session (strong disable) | |
8070f5c0 MD |
364 | * LTTNG_KERNEL_METADATA |
365 | * Returns a LTTng metadata file descriptor | |
ad1c05e1 MD |
366 | * |
367 | * The returned channel will be deleted when its file descriptor is closed. | |
368 | */ | |
369 | static | |
c0e31d2e | 370 | long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 | 371 | { |
c0e31d2e MD |
372 | struct ltt_session *session = file->private_data; |
373 | ||
ad1c05e1 | 374 | switch (cmd) { |
38d024ae | 375 | case LTTNG_KERNEL_CHANNEL: |
5dbbdb43 | 376 | return lttng_abi_create_channel(file, |
38d024ae | 377 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 378 | PER_CPU_CHANNEL); |
38d024ae | 379 | case LTTNG_KERNEL_SESSION_START: |
e64957da MD |
380 | case LTTNG_KERNEL_ENABLE: |
381 | return ltt_session_enable(session); | |
38d024ae | 382 | case LTTNG_KERNEL_SESSION_STOP: |
e64957da MD |
383 | case LTTNG_KERNEL_DISABLE: |
384 | return ltt_session_disable(session); | |
38d024ae | 385 | case LTTNG_KERNEL_METADATA: |
5dbbdb43 | 386 | return lttng_abi_create_channel(file, |
38d024ae | 387 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 388 | METADATA_CHANNEL); |
ad1c05e1 MD |
389 | default: |
390 | return -ENOIOCTLCMD; | |
391 | } | |
392 | } | |
393 | ||
03037b98 MD |
394 | /* |
395 | * Called when the last file reference is dropped. | |
396 | * | |
397 | * Big fat note: channels and events are invariant for the whole session after | |
398 | * their creation. So this session destruction also destroys all channel and | |
399 | * event structures specific to this session (they are not destroyed when their | |
400 | * individual file is released). | |
401 | */ | |
ad1c05e1 | 402 | static |
03037b98 | 403 | int lttng_session_release(struct inode *inode, struct file *file) |
ad1c05e1 | 404 | { |
03037b98 | 405 | struct ltt_session *session = file->private_data; |
c269fff4 MD |
406 | |
407 | if (session) | |
408 | ltt_session_destroy(session); | |
11b5a3c2 | 409 | return 0; |
ad1c05e1 | 410 | } |
ad1c05e1 MD |
411 | |
412 | static const struct file_operations lttng_session_fops = { | |
03037b98 | 413 | .release = lttng_session_release, |
ad1c05e1 MD |
414 | .unlocked_ioctl = lttng_session_ioctl, |
415 | #ifdef CONFIG_COMPAT | |
03037b98 | 416 | .compat_ioctl = lttng_session_ioctl, |
ad1c05e1 | 417 | #endif |
11b5a3c2 | 418 | }; |
ad1c05e1 MD |
419 | |
420 | static | |
c0e31d2e | 421 | int lttng_abi_open_stream(struct file *channel_file) |
ad1c05e1 | 422 | { |
c0e31d2e | 423 | struct ltt_channel *channel = channel_file->private_data; |
ad1c05e1 MD |
424 | struct lib_ring_buffer *buf; |
425 | int stream_fd, ret; | |
11b5a3c2 | 426 | struct file *stream_file; |
ad1c05e1 | 427 | |
11b5a3c2 | 428 | buf = channel->ops->buffer_read_open(channel->chan); |
ad1c05e1 MD |
429 | if (!buf) |
430 | return -ENOENT; | |
431 | ||
1c25284c | 432 | stream_fd = get_unused_fd(); |
ad1c05e1 MD |
433 | if (stream_fd < 0) { |
434 | ret = stream_fd; | |
435 | goto fd_error; | |
436 | } | |
c0e31d2e | 437 | stream_file = anon_inode_getfile("[lttng_stream]", |
7f57c73c | 438 | &lib_ring_buffer_file_operations, |
ad1c05e1 | 439 | buf, O_RDWR); |
c0e31d2e MD |
440 | if (IS_ERR(stream_file)) { |
441 | ret = PTR_ERR(stream_file); | |
ad1c05e1 MD |
442 | goto file_error; |
443 | } | |
409453cb MD |
444 | /* |
445 | * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor | |
446 | * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this | |
447 | * file descriptor, so we set FMODE_PREAD here. | |
448 | */ | |
d7b6f197 | 449 | stream_file->f_mode |= FMODE_PREAD; |
c0e31d2e | 450 | fd_install(stream_fd, stream_file); |
dda6a249 MD |
451 | /* |
452 | * The stream holds a reference to the channel within the generic ring | |
453 | * buffer library, so no need to hold a refcount on the channel and | |
454 | * session files here. | |
455 | */ | |
ad1c05e1 MD |
456 | return stream_fd; |
457 | ||
458 | file_error: | |
459 | put_unused_fd(stream_fd); | |
460 | fd_error: | |
11b5a3c2 | 461 | channel->ops->buffer_read_close(buf); |
ad1c05e1 MD |
462 | return ret; |
463 | } | |
464 | ||
653fe716 | 465 | static |
c0e31d2e | 466 | int lttng_abi_create_event(struct file *channel_file, |
38d024ae | 467 | struct lttng_kernel_event __user *uevent_param) |
653fe716 | 468 | { |
c0e31d2e | 469 | struct ltt_channel *channel = channel_file->private_data; |
653fe716 | 470 | struct ltt_event *event; |
38d024ae | 471 | struct lttng_kernel_event event_param; |
653fe716 | 472 | int event_fd, ret; |
11b5a3c2 | 473 | struct file *event_file; |
653fe716 MD |
474 | |
475 | if (copy_from_user(&event_param, uevent_param, sizeof(event_param))) | |
476 | return -EFAULT; | |
30bdb6e4 | 477 | event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
e0a7a7c4 | 478 | switch (event_param.instrumentation) { |
ab2277d6 | 479 | case LTTNG_KERNEL_KPROBE: |
e0a7a7c4 MD |
480 | event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
481 | break; | |
ab2277d6 | 482 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
483 | event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
484 | break; | |
485 | default: | |
486 | break; | |
487 | } | |
1c25284c | 488 | event_fd = get_unused_fd(); |
653fe716 MD |
489 | if (event_fd < 0) { |
490 | ret = event_fd; | |
491 | goto fd_error; | |
492 | } | |
c0e31d2e | 493 | event_file = anon_inode_getfile("[lttng_event]", |
3b923e5b | 494 | <tng_event_fops, |
03037b98 | 495 | NULL, O_RDWR); |
c0e31d2e MD |
496 | if (IS_ERR(event_file)) { |
497 | ret = PTR_ERR(event_file); | |
653fe716 MD |
498 | goto file_error; |
499 | } | |
03037b98 MD |
500 | /* |
501 | * We tolerate no failure path after event creation. It will stay | |
502 | * invariant for the rest of the session. | |
503 | */ | |
30bdb6e4 | 504 | event = ltt_event_create(channel, &event_param, NULL); |
03037b98 | 505 | if (!event) { |
271b6681 | 506 | ret = -EINVAL; |
d6d808f3 | 507 | goto event_error; |
03037b98 | 508 | } |
c0e31d2e MD |
509 | event_file->private_data = event; |
510 | fd_install(event_fd, event_file); | |
653fe716 | 511 | /* The event holds a reference on the channel */ |
b0caa15a | 512 | atomic_long_inc(&channel_file->f_count); |
653fe716 MD |
513 | return event_fd; |
514 | ||
03037b98 | 515 | event_error: |
c0e31d2e | 516 | fput(event_file); |
653fe716 MD |
517 | file_error: |
518 | put_unused_fd(event_fd); | |
519 | fd_error: | |
653fe716 MD |
520 | return ret; |
521 | } | |
ad1c05e1 MD |
522 | |
523 | /** | |
524 | * lttng_channel_ioctl - lttng syscall through ioctl | |
525 | * | |
c0e31d2e | 526 | * @file: the file |
ad1c05e1 MD |
527 | * @cmd: the command |
528 | * @arg: command arg | |
529 | * | |
530 | * This ioctl implements lttng commands: | |
38d024ae | 531 | * LTTNG_KERNEL_STREAM |
ad1c05e1 MD |
532 | * Returns an event stream file descriptor or failure. |
533 | * (typically, one event stream records events from one CPU) | |
38d024ae | 534 | * LTTNG_KERNEL_EVENT |
ad1c05e1 | 535 | * Returns an event file descriptor or failure. |
8070f5c0 MD |
536 | * LTTNG_KERNEL_CONTEXT |
537 | * Prepend a context field to each event in the channel | |
e64957da MD |
538 | * LTTNG_KERNEL_ENABLE |
539 | * Enable recording for events in this channel (weak enable) | |
540 | * LTTNG_KERNEL_DISABLE | |
541 | * Disable recording for events in this channel (strong disable) | |
baf20995 | 542 | * |
baf20995 MD |
543 | * Channel and event file descriptors also hold a reference on the session. |
544 | */ | |
ad1c05e1 | 545 | static |
c0e31d2e | 546 | long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
baf20995 | 547 | { |
8070f5c0 MD |
548 | struct ltt_channel *channel = file->private_data; |
549 | ||
baf20995 | 550 | switch (cmd) { |
38d024ae | 551 | case LTTNG_KERNEL_STREAM: |
c0e31d2e | 552 | return lttng_abi_open_stream(file); |
38d024ae MD |
553 | case LTTNG_KERNEL_EVENT: |
554 | return lttng_abi_create_event(file, (struct lttng_kernel_event __user *) arg); | |
8070f5c0 MD |
555 | case LTTNG_KERNEL_CONTEXT: |
556 | return lttng_abi_add_context(file, | |
557 | (struct lttng_kernel_context __user *) arg, | |
558 | &channel->ctx, channel->session); | |
e64957da MD |
559 | case LTTNG_KERNEL_ENABLE: |
560 | return ltt_channel_enable(channel); | |
561 | case LTTNG_KERNEL_DISABLE: | |
562 | return ltt_channel_disable(channel); | |
baf20995 MD |
563 | default: |
564 | return -ENOIOCTLCMD; | |
565 | } | |
566 | } | |
567 | ||
5dbbdb43 MD |
568 | /** |
569 | * lttng_metadata_ioctl - lttng syscall through ioctl | |
570 | * | |
571 | * @file: the file | |
572 | * @cmd: the command | |
573 | * @arg: command arg | |
574 | * | |
575 | * This ioctl implements lttng commands: | |
38d024ae | 576 | * LTTNG_KERNEL_STREAM |
5dbbdb43 MD |
577 | * Returns an event stream file descriptor or failure. |
578 | * | |
579 | * Channel and event file descriptors also hold a reference on the session. | |
580 | */ | |
581 | static | |
582 | long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
583 | { | |
584 | switch (cmd) { | |
38d024ae | 585 | case LTTNG_KERNEL_STREAM: |
5dbbdb43 MD |
586 | return lttng_abi_open_stream(file); |
587 | default: | |
588 | return -ENOIOCTLCMD; | |
589 | } | |
590 | } | |
591 | ||
653fe716 MD |
592 | /** |
593 | * lttng_channel_poll - lttng stream addition/removal monitoring | |
594 | * | |
c0e31d2e | 595 | * @file: the file |
653fe716 MD |
596 | * @wait: poll table |
597 | */ | |
c0e31d2e | 598 | unsigned int lttng_channel_poll(struct file *file, poll_table *wait) |
653fe716 | 599 | { |
c0e31d2e | 600 | struct ltt_channel *channel = file->private_data; |
653fe716 MD |
601 | unsigned int mask = 0; |
602 | ||
c0e31d2e | 603 | if (file->f_mode & FMODE_READ) { |
a33e44a6 | 604 | poll_wait_set_exclusive(wait); |
24cedcfe MD |
605 | poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan), |
606 | wait); | |
653fe716 | 607 | |
254ec7bc MD |
608 | if (channel->ops->is_disabled(channel->chan)) |
609 | return POLLERR; | |
24cedcfe | 610 | if (channel->ops->is_finalized(channel->chan)) |
653fe716 | 611 | return POLLHUP; |
f71ecafa | 612 | if (channel->ops->buffer_has_read_closed_stream(channel->chan)) |
653fe716 | 613 | return POLLIN | POLLRDNORM; |
f71ecafa | 614 | return 0; |
653fe716 MD |
615 | } |
616 | return mask; | |
617 | ||
618 | } | |
619 | ||
0a84a57f MD |
620 | static |
621 | int lttng_channel_release(struct inode *inode, struct file *file) | |
622 | { | |
623 | struct ltt_channel *channel = file->private_data; | |
c269fff4 MD |
624 | |
625 | if (channel) | |
626 | fput(channel->session->file); | |
0a84a57f MD |
627 | return 0; |
628 | } | |
629 | ||
ad1c05e1 | 630 | static const struct file_operations lttng_channel_fops = { |
03037b98 | 631 | .release = lttng_channel_release, |
653fe716 | 632 | .poll = lttng_channel_poll, |
ad1c05e1 | 633 | .unlocked_ioctl = lttng_channel_ioctl, |
baf20995 | 634 | #ifdef CONFIG_COMPAT |
03037b98 | 635 | .compat_ioctl = lttng_channel_ioctl, |
baf20995 | 636 | #endif |
11b5a3c2 | 637 | }; |
baf20995 | 638 | |
5dbbdb43 MD |
639 | static const struct file_operations lttng_metadata_fops = { |
640 | .release = lttng_channel_release, | |
641 | .unlocked_ioctl = lttng_metadata_ioctl, | |
642 | #ifdef CONFIG_COMPAT | |
643 | .compat_ioctl = lttng_metadata_ioctl, | |
644 | #endif | |
645 | }; | |
646 | ||
8070f5c0 MD |
647 | /** |
648 | * lttng_event_ioctl - lttng syscall through ioctl | |
649 | * | |
650 | * @file: the file | |
651 | * @cmd: the command | |
652 | * @arg: command arg | |
653 | * | |
654 | * This ioctl implements lttng commands: | |
8070f5c0 MD |
655 | * LTTNG_KERNEL_CONTEXT |
656 | * Prepend a context field to each record of this event | |
e64957da MD |
657 | * LTTNG_KERNEL_ENABLE |
658 | * Enable recording for this event (weak enable) | |
659 | * LTTNG_KERNEL_DISABLE | |
660 | * Disable recording for this event (strong disable) | |
8070f5c0 MD |
661 | */ |
662 | static | |
663 | long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
664 | { | |
665 | struct ltt_event *event = file->private_data; | |
666 | ||
667 | switch (cmd) { | |
668 | case LTTNG_KERNEL_CONTEXT: | |
669 | return lttng_abi_add_context(file, | |
670 | (struct lttng_kernel_context __user *) arg, | |
671 | &event->ctx, event->chan->session); | |
e64957da MD |
672 | case LTTNG_KERNEL_ENABLE: |
673 | return ltt_event_enable(event); | |
674 | case LTTNG_KERNEL_DISABLE: | |
675 | return ltt_event_disable(event); | |
8070f5c0 MD |
676 | default: |
677 | return -ENOIOCTLCMD; | |
678 | } | |
679 | } | |
680 | ||
0a84a57f MD |
681 | static |
682 | int lttng_event_release(struct inode *inode, struct file *file) | |
683 | { | |
684 | struct ltt_event *event = file->private_data; | |
c269fff4 | 685 | |
aa7c23a9 | 686 | if (event) |
c269fff4 | 687 | fput(event->chan->file); |
0a84a57f MD |
688 | return 0; |
689 | } | |
690 | ||
3b923e5b | 691 | /* TODO: filter control ioctl */ |
0a84a57f MD |
692 | static const struct file_operations lttng_event_fops = { |
693 | .release = lttng_event_release, | |
8070f5c0 MD |
694 | .unlocked_ioctl = lttng_event_ioctl, |
695 | #ifdef CONFIG_COMPAT | |
696 | .compat_ioctl = lttng_event_ioctl, | |
697 | #endif | |
11b5a3c2 | 698 | }; |
0a84a57f | 699 | |
1c25284c | 700 | int __init ltt_debugfs_abi_init(void) |
baf20995 MD |
701 | { |
702 | int ret = 0; | |
703 | ||
6d2a620c | 704 | wrapper_vmalloc_sync_all(); |
11b5a3c2 | 705 | lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL, |
f3d01b96 | 706 | <tng_fops); |
11b5a3c2 | 707 | if (IS_ERR(lttng_dentry) || !lttng_dentry) { |
baf20995 MD |
708 | printk(KERN_ERR "Error creating LTTng control file\n"); |
709 | ret = -ENOMEM; | |
710 | goto error; | |
711 | } | |
712 | error: | |
713 | return ret; | |
714 | } | |
715 | ||
1c25284c | 716 | void __exit ltt_debugfs_abi_exit(void) |
baf20995 | 717 | { |
11b5a3c2 | 718 | debugfs_remove(lttng_dentry); |
baf20995 | 719 | } |