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 | |
a33c9927 MD |
52 | /* |
53 | * Teardown management: opened file descriptors keep a refcount on the module, | |
54 | * so it can only exit when all file descriptors are closed. | |
55 | */ | |
56 | ||
5dbbdb43 MD |
57 | enum channel_type { |
58 | PER_CPU_CHANNEL, | |
5dbbdb43 MD |
59 | METADATA_CHANNEL, |
60 | }; | |
61 | ||
ad1c05e1 | 62 | static |
baf20995 MD |
63 | int lttng_abi_create_session(void) |
64 | { | |
65 | struct ltt_session *session; | |
c0e31d2e | 66 | struct file *session_file; |
11b5a3c2 | 67 | int session_fd, ret; |
baf20995 | 68 | |
653fe716 | 69 | session = ltt_session_create(); |
baf20995 MD |
70 | if (!session) |
71 | return -ENOMEM; | |
1c25284c | 72 | session_fd = get_unused_fd(); |
baf20995 MD |
73 | if (session_fd < 0) { |
74 | ret = session_fd; | |
75 | goto fd_error; | |
76 | } | |
c0e31d2e | 77 | session_file = anon_inode_getfile("[lttng_session]", |
ad1c05e1 | 78 | <tng_session_fops, |
baf20995 | 79 | session, O_RDWR); |
c0e31d2e MD |
80 | if (IS_ERR(session_file)) { |
81 | ret = PTR_ERR(session_file); | |
baf20995 MD |
82 | goto file_error; |
83 | } | |
c0e31d2e MD |
84 | session->file = session_file; |
85 | fd_install(session_fd, session_file); | |
baf20995 MD |
86 | return session_fd; |
87 | ||
88 | file_error: | |
89 | put_unused_fd(session_fd); | |
90 | fd_error: | |
91 | ltt_session_destroy(session); | |
92 | return ret; | |
93 | } | |
94 | ||
271b6681 MD |
95 | static |
96 | int lttng_abi_tracepoint_list(void) | |
97 | { | |
98 | struct file *tracepoint_list_file; | |
99 | int file_fd, ret; | |
100 | ||
101 | file_fd = get_unused_fd(); | |
102 | if (file_fd < 0) { | |
103 | ret = file_fd; | |
104 | goto fd_error; | |
105 | } | |
30f18bf0 | 106 | |
271b6681 MD |
107 | tracepoint_list_file = anon_inode_getfile("[lttng_session]", |
108 | <tng_tracepoint_list_fops, | |
109 | NULL, O_RDWR); | |
110 | if (IS_ERR(tracepoint_list_file)) { | |
111 | ret = PTR_ERR(tracepoint_list_file); | |
112 | goto file_error; | |
113 | } | |
30f18bf0 MD |
114 | ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file); |
115 | if (ret < 0) | |
116 | goto open_error; | |
271b6681 | 117 | fd_install(file_fd, tracepoint_list_file); |
30f18bf0 MD |
118 | if (file_fd < 0) { |
119 | ret = file_fd; | |
120 | goto fd_error; | |
121 | } | |
271b6681 MD |
122 | return file_fd; |
123 | ||
30f18bf0 MD |
124 | open_error: |
125 | fput(tracepoint_list_file); | |
271b6681 MD |
126 | file_error: |
127 | put_unused_fd(file_fd); | |
128 | fd_error: | |
129 | return ret; | |
130 | } | |
131 | ||
80c16bcf MD |
132 | static |
133 | long lttng_abi_tracer_version(struct file *file, | |
134 | struct lttng_kernel_tracer_version __user *uversion_param) | |
135 | { | |
136 | struct lttng_kernel_tracer_version v; | |
137 | ||
138 | v.version = LTTNG_VERSION; | |
139 | v.patchlevel = LTTNG_PATCHLEVEL; | |
140 | v.sublevel = LTTNG_SUBLEVEL; | |
141 | ||
142 | if (copy_to_user(uversion_param, &v, sizeof(v))) | |
143 | return -EFAULT; | |
144 | return 0; | |
145 | } | |
146 | ||
8070f5c0 MD |
147 | static |
148 | long lttng_abi_add_context(struct file *file, | |
149 | struct lttng_kernel_context __user *ucontext_param, | |
150 | struct lttng_ctx **ctx, struct ltt_session *session) | |
151 | { | |
152 | struct lttng_kernel_context context_param; | |
153 | ||
154 | if (session->been_active) | |
155 | return -EPERM; | |
156 | ||
157 | if (copy_from_user(&context_param, ucontext_param, sizeof(context_param))) | |
158 | return -EFAULT; | |
159 | ||
160 | switch (context_param.ctx) { | |
12a313a5 | 161 | case LTTNG_KERNEL_CONTEXT_PID: |
8070f5c0 | 162 | return lttng_add_pid_to_ctx(ctx); |
a8ad3613 MD |
163 | case LTTNG_KERNEL_CONTEXT_PRIO: |
164 | return lttng_add_prio_to_ctx(ctx); | |
53f1f0ca MD |
165 | case LTTNG_KERNEL_CONTEXT_NICE: |
166 | return lttng_add_nice_to_ctx(ctx); | |
b64bc438 MD |
167 | case LTTNG_KERNEL_CONTEXT_VPID: |
168 | return lttng_add_vpid_to_ctx(ctx); | |
169 | case LTTNG_KERNEL_CONTEXT_TID: | |
170 | return lttng_add_tid_to_ctx(ctx); | |
171 | case LTTNG_KERNEL_CONTEXT_VTID: | |
172 | return lttng_add_vtid_to_ctx(ctx); | |
173 | case LTTNG_KERNEL_CONTEXT_PPID: | |
174 | return lttng_add_ppid_to_ctx(ctx); | |
175 | case LTTNG_KERNEL_CONTEXT_VPPID: | |
176 | return lttng_add_vppid_to_ctx(ctx); | |
12a313a5 | 177 | case LTTNG_KERNEL_CONTEXT_PERF_COUNTER: |
c24a0d71 MD |
178 | context_param.u.perf_counter.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
179 | return lttng_add_perf_counter_to_ctx(context_param.u.perf_counter.type, | |
180 | context_param.u.perf_counter.config, | |
181 | context_param.u.perf_counter.name, | |
182 | ctx); | |
25b2f99a MD |
183 | case LTTNG_KERNEL_CONTEXT_COMM: |
184 | return lttng_add_comm_to_ctx(ctx); | |
8070f5c0 MD |
185 | default: |
186 | return -EINVAL; | |
187 | } | |
188 | } | |
189 | ||
ad1c05e1 MD |
190 | /** |
191 | * lttng_ioctl - lttng syscall through ioctl | |
192 | * | |
c0e31d2e | 193 | * @file: the file |
ad1c05e1 MD |
194 | * @cmd: the command |
195 | * @arg: command arg | |
196 | * | |
197 | * This ioctl implements lttng commands: | |
38d024ae | 198 | * LTTNG_KERNEL_SESSION |
ad1c05e1 | 199 | * Returns a LTTng trace session file descriptor |
271b6681 MD |
200 | * LTTNG_KERNEL_TRACER_VERSION |
201 | * Returns the LTTng kernel tracer version | |
202 | * LTTNG_KERNEL_TRACEPOINT_LIST | |
203 | * Returns a file descriptor listing available tracepoints | |
360f38ea MD |
204 | * LTTNG_KERNEL_WAIT_QUIESCENT |
205 | * Returns after all previously running probes have completed | |
ad1c05e1 MD |
206 | * |
207 | * The returned session will be deleted when its file descriptor is closed. | |
208 | */ | |
209 | static | |
c0e31d2e | 210 | long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 MD |
211 | { |
212 | switch (cmd) { | |
38d024ae | 213 | case LTTNG_KERNEL_SESSION: |
ad1c05e1 | 214 | return lttng_abi_create_session(); |
80c16bcf MD |
215 | case LTTNG_KERNEL_TRACER_VERSION: |
216 | return lttng_abi_tracer_version(file, | |
217 | (struct lttng_kernel_tracer_version __user *) arg); | |
271b6681 MD |
218 | case LTTNG_KERNEL_TRACEPOINT_LIST: |
219 | return lttng_abi_tracepoint_list(); | |
5f7f9078 MD |
220 | case LTTNG_KERNEL_WAIT_QUIESCENT: |
221 | synchronize_trace(); | |
222 | return 0; | |
ad1c05e1 MD |
223 | default: |
224 | return -ENOIOCTLCMD; | |
225 | } | |
226 | } | |
227 | ||
ad1c05e1 | 228 | static const struct file_operations lttng_fops = { |
a33c9927 | 229 | .owner = THIS_MODULE, |
ad1c05e1 MD |
230 | .unlocked_ioctl = lttng_ioctl, |
231 | #ifdef CONFIG_COMPAT | |
03037b98 | 232 | .compat_ioctl = lttng_ioctl, |
ad1c05e1 | 233 | #endif |
11b5a3c2 | 234 | }; |
ad1c05e1 | 235 | |
5dbbdb43 MD |
236 | /* |
237 | * We tolerate no failure in this function (if one happens, we print a dmesg | |
238 | * error, but cannot return any error, because the channel information is | |
239 | * invariant. | |
240 | */ | |
241 | static | |
242 | void lttng_metadata_create_events(struct file *channel_file) | |
243 | { | |
244 | struct ltt_channel *channel = channel_file->private_data; | |
e70a4758 | 245 | static struct lttng_kernel_event metadata_params = { |
ab2277d6 | 246 | .instrumentation = LTTNG_KERNEL_TRACEPOINT, |
e70a4758 MD |
247 | .name = "lttng_metadata", |
248 | }; | |
5dbbdb43 MD |
249 | struct ltt_event *event; |
250 | int ret; | |
5dbbdb43 | 251 | |
5dbbdb43 MD |
252 | /* |
253 | * We tolerate no failure path after event creation. It will stay | |
254 | * invariant for the rest of the session. | |
255 | */ | |
30bdb6e4 | 256 | event = ltt_event_create(channel, &metadata_params, NULL); |
5dbbdb43 | 257 | if (!event) { |
588e6a7f | 258 | ret = -EINVAL; |
271b6681 | 259 | goto create_error; |
5dbbdb43 MD |
260 | } |
261 | return; | |
262 | ||
85a9ca7f | 263 | create_error: |
5dbbdb43 MD |
264 | WARN_ON(1); |
265 | return; /* not allowed to return error */ | |
266 | } | |
267 | ||
268 | static | |
c0e31d2e | 269 | int lttng_abi_create_channel(struct file *session_file, |
38d024ae | 270 | struct lttng_kernel_channel __user *uchan_param, |
5dbbdb43 | 271 | enum channel_type channel_type) |
baf20995 | 272 | { |
c0e31d2e | 273 | struct ltt_session *session = session_file->private_data; |
5dbbdb43 MD |
274 | const struct file_operations *fops; |
275 | const char *transport_name; | |
baf20995 | 276 | struct ltt_channel *chan; |
c0e31d2e | 277 | struct file *chan_file; |
38d024ae | 278 | struct lttng_kernel_channel chan_param; |
baf20995 | 279 | int chan_fd; |
ad1c05e1 | 280 | int ret = 0; |
baf20995 | 281 | |
653fe716 | 282 | if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param))) |
baf20995 | 283 | return -EFAULT; |
1c25284c | 284 | chan_fd = get_unused_fd(); |
baf20995 MD |
285 | if (chan_fd < 0) { |
286 | ret = chan_fd; | |
287 | goto fd_error; | |
288 | } | |
c0e31d2e | 289 | chan_file = anon_inode_getfile("[lttng_channel]", |
ad1c05e1 | 290 | <tng_channel_fops, |
03037b98 | 291 | NULL, O_RDWR); |
c0e31d2e MD |
292 | if (IS_ERR(chan_file)) { |
293 | ret = PTR_ERR(chan_file); | |
baf20995 MD |
294 | goto file_error; |
295 | } | |
5dbbdb43 MD |
296 | switch (channel_type) { |
297 | case PER_CPU_CHANNEL: | |
96ba7208 JD |
298 | if (chan_param.output == LTTNG_KERNEL_SPLICE) { |
299 | transport_name = chan_param.overwrite ? | |
300 | "relay-overwrite" : "relay-discard"; | |
301 | } else if (chan_param.output == LTTNG_KERNEL_MMAP) { | |
302 | transport_name = chan_param.overwrite ? | |
303 | "relay-overwrite-mmap" : "relay-discard-mmap"; | |
304 | } else { | |
305 | return -EINVAL; | |
306 | } | |
5dbbdb43 MD |
307 | fops = <tng_channel_fops; |
308 | break; | |
5dbbdb43 | 309 | case METADATA_CHANNEL: |
96ba7208 JD |
310 | if (chan_param.output == LTTNG_KERNEL_SPLICE) |
311 | transport_name = "relay-metadata"; | |
312 | else if (chan_param.output == LTTNG_KERNEL_MMAP) | |
313 | transport_name = "relay-metadata-mmap"; | |
314 | else | |
315 | return -EINVAL; | |
5dbbdb43 MD |
316 | fops = <tng_metadata_fops; |
317 | break; | |
318 | default: | |
319 | transport_name = "<unknown>"; | |
320 | break; | |
321 | } | |
03037b98 MD |
322 | /* |
323 | * We tolerate no failure path after channel creation. It will stay | |
324 | * invariant for the rest of the session. | |
325 | */ | |
5dbbdb43 | 326 | chan = ltt_channel_create(session, transport_name, NULL, |
11b5a3c2 MD |
327 | chan_param.subbuf_size, |
328 | chan_param.num_subbuf, | |
329 | chan_param.switch_timer_interval, | |
330 | chan_param.read_timer_interval); | |
03037b98 | 331 | if (!chan) { |
f3d01b96 | 332 | ret = -EINVAL; |
03037b98 MD |
333 | goto chan_error; |
334 | } | |
11b5a3c2 | 335 | chan->file = chan_file; |
c0e31d2e MD |
336 | chan_file->private_data = chan; |
337 | fd_install(chan_fd, chan_file); | |
cd4bd11f | 338 | if (channel_type == METADATA_CHANNEL) { |
cd4bd11f | 339 | session->metadata = chan; |
4f1c3952 | 340 | lttng_metadata_create_events(chan_file); |
cd4bd11f | 341 | } |
5dbbdb43 | 342 | |
ad1c05e1 | 343 | /* The channel created holds a reference on the session */ |
b0caa15a | 344 | atomic_long_inc(&session_file->f_count); |
ad1c05e1 | 345 | |
baf20995 MD |
346 | return chan_fd; |
347 | ||
03037b98 | 348 | chan_error: |
c0e31d2e | 349 | fput(chan_file); |
baf20995 MD |
350 | file_error: |
351 | put_unused_fd(chan_fd); | |
352 | fd_error: | |
baf20995 MD |
353 | return ret; |
354 | } | |
355 | ||
356 | /** | |
ad1c05e1 | 357 | * lttng_session_ioctl - lttng session fd ioctl |
baf20995 | 358 | * |
c0e31d2e | 359 | * @file: the file |
baf20995 MD |
360 | * @cmd: the command |
361 | * @arg: command arg | |
362 | * | |
363 | * This ioctl implements lttng commands: | |
38d024ae | 364 | * LTTNG_KERNEL_CHANNEL |
baf20995 | 365 | * Returns a LTTng channel file descriptor |
e64957da MD |
366 | * LTTNG_KERNEL_ENABLE |
367 | * Enables tracing for a session (weak enable) | |
368 | * LTTNG_KERNEL_DISABLE | |
369 | * Disables tracing for a session (strong disable) | |
8070f5c0 MD |
370 | * LTTNG_KERNEL_METADATA |
371 | * Returns a LTTng metadata file descriptor | |
ad1c05e1 MD |
372 | * |
373 | * The returned channel will be deleted when its file descriptor is closed. | |
374 | */ | |
375 | static | |
c0e31d2e | 376 | long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
ad1c05e1 | 377 | { |
c0e31d2e MD |
378 | struct ltt_session *session = file->private_data; |
379 | ||
ad1c05e1 | 380 | switch (cmd) { |
38d024ae | 381 | case LTTNG_KERNEL_CHANNEL: |
5dbbdb43 | 382 | return lttng_abi_create_channel(file, |
38d024ae | 383 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 384 | PER_CPU_CHANNEL); |
38d024ae | 385 | case LTTNG_KERNEL_SESSION_START: |
e64957da MD |
386 | case LTTNG_KERNEL_ENABLE: |
387 | return ltt_session_enable(session); | |
38d024ae | 388 | case LTTNG_KERNEL_SESSION_STOP: |
e64957da MD |
389 | case LTTNG_KERNEL_DISABLE: |
390 | return ltt_session_disable(session); | |
38d024ae | 391 | case LTTNG_KERNEL_METADATA: |
5dbbdb43 | 392 | return lttng_abi_create_channel(file, |
38d024ae | 393 | (struct lttng_kernel_channel __user *) arg, |
5dbbdb43 | 394 | METADATA_CHANNEL); |
ad1c05e1 MD |
395 | default: |
396 | return -ENOIOCTLCMD; | |
397 | } | |
398 | } | |
399 | ||
03037b98 MD |
400 | /* |
401 | * Called when the last file reference is dropped. | |
402 | * | |
403 | * Big fat note: channels and events are invariant for the whole session after | |
404 | * their creation. So this session destruction also destroys all channel and | |
405 | * event structures specific to this session (they are not destroyed when their | |
406 | * individual file is released). | |
407 | */ | |
ad1c05e1 | 408 | static |
03037b98 | 409 | int lttng_session_release(struct inode *inode, struct file *file) |
ad1c05e1 | 410 | { |
03037b98 | 411 | struct ltt_session *session = file->private_data; |
c269fff4 MD |
412 | |
413 | if (session) | |
414 | ltt_session_destroy(session); | |
11b5a3c2 | 415 | return 0; |
ad1c05e1 | 416 | } |
ad1c05e1 MD |
417 | |
418 | static const struct file_operations lttng_session_fops = { | |
a33c9927 | 419 | .owner = THIS_MODULE, |
03037b98 | 420 | .release = lttng_session_release, |
ad1c05e1 MD |
421 | .unlocked_ioctl = lttng_session_ioctl, |
422 | #ifdef CONFIG_COMPAT | |
03037b98 | 423 | .compat_ioctl = lttng_session_ioctl, |
ad1c05e1 | 424 | #endif |
11b5a3c2 | 425 | }; |
ad1c05e1 MD |
426 | |
427 | static | |
c0e31d2e | 428 | int lttng_abi_open_stream(struct file *channel_file) |
ad1c05e1 | 429 | { |
c0e31d2e | 430 | struct ltt_channel *channel = channel_file->private_data; |
ad1c05e1 MD |
431 | struct lib_ring_buffer *buf; |
432 | int stream_fd, ret; | |
11b5a3c2 | 433 | struct file *stream_file; |
ad1c05e1 | 434 | |
11b5a3c2 | 435 | buf = channel->ops->buffer_read_open(channel->chan); |
ad1c05e1 MD |
436 | if (!buf) |
437 | return -ENOENT; | |
438 | ||
1c25284c | 439 | stream_fd = get_unused_fd(); |
ad1c05e1 MD |
440 | if (stream_fd < 0) { |
441 | ret = stream_fd; | |
442 | goto fd_error; | |
443 | } | |
c0e31d2e | 444 | stream_file = anon_inode_getfile("[lttng_stream]", |
7f57c73c | 445 | &lib_ring_buffer_file_operations, |
ad1c05e1 | 446 | buf, O_RDWR); |
c0e31d2e MD |
447 | if (IS_ERR(stream_file)) { |
448 | ret = PTR_ERR(stream_file); | |
ad1c05e1 MD |
449 | goto file_error; |
450 | } | |
409453cb MD |
451 | /* |
452 | * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor | |
453 | * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this | |
454 | * file descriptor, so we set FMODE_PREAD here. | |
455 | */ | |
d7b6f197 | 456 | stream_file->f_mode |= FMODE_PREAD; |
c0e31d2e | 457 | fd_install(stream_fd, stream_file); |
dda6a249 MD |
458 | /* |
459 | * The stream holds a reference to the channel within the generic ring | |
460 | * buffer library, so no need to hold a refcount on the channel and | |
461 | * session files here. | |
462 | */ | |
ad1c05e1 MD |
463 | return stream_fd; |
464 | ||
465 | file_error: | |
466 | put_unused_fd(stream_fd); | |
467 | fd_error: | |
11b5a3c2 | 468 | channel->ops->buffer_read_close(buf); |
ad1c05e1 MD |
469 | return ret; |
470 | } | |
471 | ||
653fe716 | 472 | static |
c0e31d2e | 473 | int lttng_abi_create_event(struct file *channel_file, |
38d024ae | 474 | struct lttng_kernel_event __user *uevent_param) |
653fe716 | 475 | { |
c0e31d2e | 476 | struct ltt_channel *channel = channel_file->private_data; |
653fe716 | 477 | struct ltt_event *event; |
38d024ae | 478 | struct lttng_kernel_event event_param; |
653fe716 | 479 | int event_fd, ret; |
11b5a3c2 | 480 | struct file *event_file; |
653fe716 MD |
481 | |
482 | if (copy_from_user(&event_param, uevent_param, sizeof(event_param))) | |
483 | return -EFAULT; | |
30bdb6e4 | 484 | event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
e0a7a7c4 | 485 | switch (event_param.instrumentation) { |
ab2277d6 | 486 | case LTTNG_KERNEL_KPROBE: |
e0a7a7c4 MD |
487 | event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
488 | break; | |
ab2277d6 | 489 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
490 | event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; |
491 | break; | |
492 | default: | |
493 | break; | |
494 | } | |
1c25284c | 495 | event_fd = get_unused_fd(); |
653fe716 MD |
496 | if (event_fd < 0) { |
497 | ret = event_fd; | |
498 | goto fd_error; | |
499 | } | |
c0e31d2e | 500 | event_file = anon_inode_getfile("[lttng_event]", |
3b923e5b | 501 | <tng_event_fops, |
03037b98 | 502 | NULL, O_RDWR); |
c0e31d2e MD |
503 | if (IS_ERR(event_file)) { |
504 | ret = PTR_ERR(event_file); | |
653fe716 MD |
505 | goto file_error; |
506 | } | |
03037b98 MD |
507 | /* |
508 | * We tolerate no failure path after event creation. It will stay | |
509 | * invariant for the rest of the session. | |
510 | */ | |
30bdb6e4 | 511 | event = ltt_event_create(channel, &event_param, NULL); |
03037b98 | 512 | if (!event) { |
271b6681 | 513 | ret = -EINVAL; |
d6d808f3 | 514 | goto event_error; |
03037b98 | 515 | } |
c0e31d2e MD |
516 | event_file->private_data = event; |
517 | fd_install(event_fd, event_file); | |
653fe716 | 518 | /* The event holds a reference on the channel */ |
b0caa15a | 519 | atomic_long_inc(&channel_file->f_count); |
653fe716 MD |
520 | return event_fd; |
521 | ||
03037b98 | 522 | event_error: |
c0e31d2e | 523 | fput(event_file); |
653fe716 MD |
524 | file_error: |
525 | put_unused_fd(event_fd); | |
526 | fd_error: | |
653fe716 MD |
527 | return ret; |
528 | } | |
ad1c05e1 MD |
529 | |
530 | /** | |
531 | * lttng_channel_ioctl - lttng syscall through ioctl | |
532 | * | |
c0e31d2e | 533 | * @file: the file |
ad1c05e1 MD |
534 | * @cmd: the command |
535 | * @arg: command arg | |
536 | * | |
537 | * This ioctl implements lttng commands: | |
38d024ae | 538 | * LTTNG_KERNEL_STREAM |
ad1c05e1 MD |
539 | * Returns an event stream file descriptor or failure. |
540 | * (typically, one event stream records events from one CPU) | |
38d024ae | 541 | * LTTNG_KERNEL_EVENT |
ad1c05e1 | 542 | * Returns an event file descriptor or failure. |
8070f5c0 MD |
543 | * LTTNG_KERNEL_CONTEXT |
544 | * Prepend a context field to each event in the channel | |
e64957da MD |
545 | * LTTNG_KERNEL_ENABLE |
546 | * Enable recording for events in this channel (weak enable) | |
547 | * LTTNG_KERNEL_DISABLE | |
548 | * Disable recording for events in this channel (strong disable) | |
baf20995 | 549 | * |
baf20995 MD |
550 | * Channel and event file descriptors also hold a reference on the session. |
551 | */ | |
ad1c05e1 | 552 | static |
c0e31d2e | 553 | long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
baf20995 | 554 | { |
8070f5c0 MD |
555 | struct ltt_channel *channel = file->private_data; |
556 | ||
baf20995 | 557 | switch (cmd) { |
38d024ae | 558 | case LTTNG_KERNEL_STREAM: |
c0e31d2e | 559 | return lttng_abi_open_stream(file); |
38d024ae MD |
560 | case LTTNG_KERNEL_EVENT: |
561 | return lttng_abi_create_event(file, (struct lttng_kernel_event __user *) arg); | |
8070f5c0 MD |
562 | case LTTNG_KERNEL_CONTEXT: |
563 | return lttng_abi_add_context(file, | |
564 | (struct lttng_kernel_context __user *) arg, | |
565 | &channel->ctx, channel->session); | |
e64957da MD |
566 | case LTTNG_KERNEL_ENABLE: |
567 | return ltt_channel_enable(channel); | |
568 | case LTTNG_KERNEL_DISABLE: | |
569 | return ltt_channel_disable(channel); | |
baf20995 MD |
570 | default: |
571 | return -ENOIOCTLCMD; | |
572 | } | |
573 | } | |
574 | ||
5dbbdb43 MD |
575 | /** |
576 | * lttng_metadata_ioctl - lttng syscall through ioctl | |
577 | * | |
578 | * @file: the file | |
579 | * @cmd: the command | |
580 | * @arg: command arg | |
581 | * | |
582 | * This ioctl implements lttng commands: | |
38d024ae | 583 | * LTTNG_KERNEL_STREAM |
5dbbdb43 MD |
584 | * Returns an event stream file descriptor or failure. |
585 | * | |
586 | * Channel and event file descriptors also hold a reference on the session. | |
587 | */ | |
588 | static | |
589 | long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
590 | { | |
591 | switch (cmd) { | |
38d024ae | 592 | case LTTNG_KERNEL_STREAM: |
5dbbdb43 MD |
593 | return lttng_abi_open_stream(file); |
594 | default: | |
595 | return -ENOIOCTLCMD; | |
596 | } | |
597 | } | |
598 | ||
653fe716 MD |
599 | /** |
600 | * lttng_channel_poll - lttng stream addition/removal monitoring | |
601 | * | |
c0e31d2e | 602 | * @file: the file |
653fe716 MD |
603 | * @wait: poll table |
604 | */ | |
c0e31d2e | 605 | unsigned int lttng_channel_poll(struct file *file, poll_table *wait) |
653fe716 | 606 | { |
c0e31d2e | 607 | struct ltt_channel *channel = file->private_data; |
653fe716 MD |
608 | unsigned int mask = 0; |
609 | ||
c0e31d2e | 610 | if (file->f_mode & FMODE_READ) { |
a33e44a6 | 611 | poll_wait_set_exclusive(wait); |
24cedcfe MD |
612 | poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan), |
613 | wait); | |
653fe716 | 614 | |
254ec7bc MD |
615 | if (channel->ops->is_disabled(channel->chan)) |
616 | return POLLERR; | |
24cedcfe | 617 | if (channel->ops->is_finalized(channel->chan)) |
653fe716 | 618 | return POLLHUP; |
f71ecafa | 619 | if (channel->ops->buffer_has_read_closed_stream(channel->chan)) |
653fe716 | 620 | return POLLIN | POLLRDNORM; |
f71ecafa | 621 | return 0; |
653fe716 MD |
622 | } |
623 | return mask; | |
624 | ||
625 | } | |
626 | ||
0a84a57f MD |
627 | static |
628 | int lttng_channel_release(struct inode *inode, struct file *file) | |
629 | { | |
630 | struct ltt_channel *channel = file->private_data; | |
c269fff4 MD |
631 | |
632 | if (channel) | |
633 | fput(channel->session->file); | |
0a84a57f MD |
634 | return 0; |
635 | } | |
636 | ||
ad1c05e1 | 637 | static const struct file_operations lttng_channel_fops = { |
a33c9927 | 638 | .owner = THIS_MODULE, |
03037b98 | 639 | .release = lttng_channel_release, |
653fe716 | 640 | .poll = lttng_channel_poll, |
ad1c05e1 | 641 | .unlocked_ioctl = lttng_channel_ioctl, |
baf20995 | 642 | #ifdef CONFIG_COMPAT |
03037b98 | 643 | .compat_ioctl = lttng_channel_ioctl, |
baf20995 | 644 | #endif |
11b5a3c2 | 645 | }; |
baf20995 | 646 | |
5dbbdb43 | 647 | static const struct file_operations lttng_metadata_fops = { |
a33c9927 | 648 | .owner = THIS_MODULE, |
5dbbdb43 MD |
649 | .release = lttng_channel_release, |
650 | .unlocked_ioctl = lttng_metadata_ioctl, | |
651 | #ifdef CONFIG_COMPAT | |
652 | .compat_ioctl = lttng_metadata_ioctl, | |
653 | #endif | |
654 | }; | |
655 | ||
8070f5c0 MD |
656 | /** |
657 | * lttng_event_ioctl - lttng syscall through ioctl | |
658 | * | |
659 | * @file: the file | |
660 | * @cmd: the command | |
661 | * @arg: command arg | |
662 | * | |
663 | * This ioctl implements lttng commands: | |
8070f5c0 MD |
664 | * LTTNG_KERNEL_CONTEXT |
665 | * Prepend a context field to each record of this event | |
e64957da MD |
666 | * LTTNG_KERNEL_ENABLE |
667 | * Enable recording for this event (weak enable) | |
668 | * LTTNG_KERNEL_DISABLE | |
669 | * Disable recording for this event (strong disable) | |
8070f5c0 MD |
670 | */ |
671 | static | |
672 | long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
673 | { | |
674 | struct ltt_event *event = file->private_data; | |
675 | ||
676 | switch (cmd) { | |
677 | case LTTNG_KERNEL_CONTEXT: | |
678 | return lttng_abi_add_context(file, | |
679 | (struct lttng_kernel_context __user *) arg, | |
680 | &event->ctx, event->chan->session); | |
e64957da MD |
681 | case LTTNG_KERNEL_ENABLE: |
682 | return ltt_event_enable(event); | |
683 | case LTTNG_KERNEL_DISABLE: | |
684 | return ltt_event_disable(event); | |
8070f5c0 MD |
685 | default: |
686 | return -ENOIOCTLCMD; | |
687 | } | |
688 | } | |
689 | ||
0a84a57f MD |
690 | static |
691 | int lttng_event_release(struct inode *inode, struct file *file) | |
692 | { | |
693 | struct ltt_event *event = file->private_data; | |
c269fff4 | 694 | |
aa7c23a9 | 695 | if (event) |
c269fff4 | 696 | fput(event->chan->file); |
0a84a57f MD |
697 | return 0; |
698 | } | |
699 | ||
3b923e5b | 700 | /* TODO: filter control ioctl */ |
0a84a57f | 701 | static const struct file_operations lttng_event_fops = { |
a33c9927 | 702 | .owner = THIS_MODULE, |
0a84a57f | 703 | .release = lttng_event_release, |
8070f5c0 MD |
704 | .unlocked_ioctl = lttng_event_ioctl, |
705 | #ifdef CONFIG_COMPAT | |
706 | .compat_ioctl = lttng_event_ioctl, | |
707 | #endif | |
11b5a3c2 | 708 | }; |
0a84a57f | 709 | |
1c25284c | 710 | int __init ltt_debugfs_abi_init(void) |
baf20995 MD |
711 | { |
712 | int ret = 0; | |
713 | ||
6d2a620c | 714 | wrapper_vmalloc_sync_all(); |
11b5a3c2 | 715 | lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL, |
f3d01b96 | 716 | <tng_fops); |
11b5a3c2 | 717 | if (IS_ERR(lttng_dentry) || !lttng_dentry) { |
baf20995 MD |
718 | printk(KERN_ERR "Error creating LTTng control file\n"); |
719 | ret = -ENOMEM; | |
720 | goto error; | |
721 | } | |
722 | error: | |
723 | return ret; | |
724 | } | |
725 | ||
1c25284c | 726 | void __exit ltt_debugfs_abi_exit(void) |
baf20995 | 727 | { |
11b5a3c2 | 728 | debugfs_remove(lttng_dentry); |
baf20995 | 729 | } |