projects / lttng-modules.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
ID tracker: implement vpid/uid/vuid/gid/vgid trackers
[lttng-modules.git] / lttng-abi.c
1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
2 *
3 * lttng-abi.c
4 *
5 * LTTng ABI
6 *
7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 *
9 * Mimic system calls for:
10 * - session creation, returns a file descriptor or failure.
11 * - channel creation, returns a file descriptor or failure.
12 * - Operates on a session file descriptor
13 * - Takes all channel options as parameters.
14 * - stream get, returns a file descriptor or failure.
15 * - Operates on a channel file descriptor.
16 * - stream notifier get, returns a file descriptor or failure.
17 * - Operates on a channel file descriptor.
18 * - event creation, returns a file descriptor or failure.
19 * - Operates on a channel file descriptor
20 * - Takes an event name as parameter
21 * - Takes an instrumentation source as parameter
22 * - e.g. tracepoints, dynamic_probes...
23 * - Takes instrumentation source specific arguments.
24 */
25
26 #include <linux/module.h>
27 #include <linux/proc_fs.h>
28 #include <linux/anon_inodes.h>
29 #include <linux/file.h>
30 #include <linux/uaccess.h>
31 #include <linux/slab.h>
32 #include <linux/err.h>
33 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */
34 #include <wrapper/ringbuffer/vfs.h>
35 #include <wrapper/ringbuffer/backend.h>
36 #include <wrapper/ringbuffer/frontend.h>
37 #include <wrapper/poll.h>
38 #include <wrapper/file.h>
39 #include <wrapper/kref.h>
40 #include <lttng-string-utils.h>
41 #include <lttng-abi.h>
42 #include <lttng-abi-old.h>
43 #include <lttng-events.h>
44 #include <lttng-tracer.h>
45 #include <lttng-tp-mempool.h>
46 #include <lib/ringbuffer/frontend_types.h>
47
48 /*
49 * This is LTTng's own personal way to create a system call as an external
50 * module. We use ioctl() on /proc/lttng.
51 */
52
53 static struct proc_dir_entry *lttng_proc_dentry;
54 static const struct file_operations lttng_fops;
55 static const struct file_operations lttng_session_fops;
56 static const struct file_operations lttng_channel_fops;
57 static const struct file_operations lttng_metadata_fops;
58 static const struct file_operations lttng_event_fops;
59 static struct file_operations lttng_stream_ring_buffer_file_operations;
60
61 static int put_u64(uint64_t val, unsigned long arg);
62
63 /*
64 * Teardown management: opened file descriptors keep a refcount on the module,
65 * so it can only exit when all file descriptors are closed.
66 */
67
68 static
69 int lttng_abi_create_session(void)
70 {
71 struct lttng_session *session;
72 struct file *session_file;
73 int session_fd, ret;
74
75 session = lttng_session_create();
76 if (!session)
77 return -ENOMEM;
78 session_fd = lttng_get_unused_fd();
79 if (session_fd < 0) {
80 ret = session_fd;
81 goto fd_error;
82 }
83 session_file = anon_inode_getfile("[lttng_session]",
84 &lttng_session_fops,
85 session, O_RDWR);
86 if (IS_ERR(session_file)) {
87 ret = PTR_ERR(session_file);
88 goto file_error;
89 }
90 session->file = session_file;
91 fd_install(session_fd, session_file);
92 return session_fd;
93
94 file_error:
95 put_unused_fd(session_fd);
96 fd_error:
97 lttng_session_destroy(session);
98 return ret;
99 }
100
101 static
102 int lttng_abi_tracepoint_list(void)
103 {
104 struct file *tracepoint_list_file;
105 int file_fd, ret;
106
107 file_fd = lttng_get_unused_fd();
108 if (file_fd < 0) {
109 ret = file_fd;
110 goto fd_error;
111 }
112
113 tracepoint_list_file = anon_inode_getfile("[lttng_tracepoint_list]",
114 &lttng_tracepoint_list_fops,
115 NULL, O_RDWR);
116 if (IS_ERR(tracepoint_list_file)) {
117 ret = PTR_ERR(tracepoint_list_file);
118 goto file_error;
119 }
120 ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
121 if (ret < 0)
122 goto open_error;
123 fd_install(file_fd, tracepoint_list_file);
124 return file_fd;
125
126 open_error:
127 fput(tracepoint_list_file);
128 file_error:
129 put_unused_fd(file_fd);
130 fd_error:
131 return ret;
132 }
133
134 #ifndef CONFIG_HAVE_SYSCALL_TRACEPOINTS
135 static inline
136 int lttng_abi_syscall_list(void)
137 {
138 return -ENOSYS;
139 }
140 #else
141 static
142 int lttng_abi_syscall_list(void)
143 {
144 struct file *syscall_list_file;
145 int file_fd, ret;
146
147 file_fd = lttng_get_unused_fd();
148 if (file_fd < 0) {
149 ret = file_fd;
150 goto fd_error;
151 }
152
153 syscall_list_file = anon_inode_getfile("[lttng_syscall_list]",
154 &lttng_syscall_list_fops,
155 NULL, O_RDWR);
156 if (IS_ERR(syscall_list_file)) {
157 ret = PTR_ERR(syscall_list_file);
158 goto file_error;
159 }
160 ret = lttng_syscall_list_fops.open(NULL, syscall_list_file);
161 if (ret < 0)
162 goto open_error;
163 fd_install(file_fd, syscall_list_file);
164 return file_fd;
165
166 open_error:
167 fput(syscall_list_file);
168 file_error:
169 put_unused_fd(file_fd);
170 fd_error:
171 return ret;
172 }
173 #endif
174
175 static
176 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version *v)
177 {
178 v->major = LTTNG_MODULES_MAJOR_VERSION;
179 v->minor = LTTNG_MODULES_MINOR_VERSION;
180 v->patchlevel = LTTNG_MODULES_PATCHLEVEL_VERSION;
181 }
182
183 static
184 void lttng_abi_tracer_abi_version(struct lttng_kernel_tracer_abi_version *v)
185 {
186 v->major = LTTNG_MODULES_ABI_MAJOR_VERSION;
187 v->minor = LTTNG_MODULES_ABI_MINOR_VERSION;
188 }
189
190 static
191 long lttng_abi_add_context(struct file *file,
192 struct lttng_kernel_context *context_param,
193 struct lttng_ctx **ctx, struct lttng_session *session)
194 {
195
196 if (session->been_active)
197 return -EPERM;
198
199 switch (context_param->ctx) {
200 case LTTNG_KERNEL_CONTEXT_PID:
201 return lttng_add_pid_to_ctx(ctx);
202 case LTTNG_KERNEL_CONTEXT_PRIO:
203 return lttng_add_prio_to_ctx(ctx);
204 case LTTNG_KERNEL_CONTEXT_NICE:
205 return lttng_add_nice_to_ctx(ctx);
206 case LTTNG_KERNEL_CONTEXT_VPID:
207 return lttng_add_vpid_to_ctx(ctx);
208 case LTTNG_KERNEL_CONTEXT_TID:
209 return lttng_add_tid_to_ctx(ctx);
210 case LTTNG_KERNEL_CONTEXT_VTID:
211 return lttng_add_vtid_to_ctx(ctx);
212 case LTTNG_KERNEL_CONTEXT_PPID:
213 return lttng_add_ppid_to_ctx(ctx);
214 case LTTNG_KERNEL_CONTEXT_VPPID:
215 return lttng_add_vppid_to_ctx(ctx);
216 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
217 context_param->u.perf_counter.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
218 return lttng_add_perf_counter_to_ctx(context_param->u.perf_counter.type,
219 context_param->u.perf_counter.config,
220 context_param->u.perf_counter.name,
221 ctx);
222 case LTTNG_KERNEL_CONTEXT_PROCNAME:
223 return lttng_add_procname_to_ctx(ctx);
224 case LTTNG_KERNEL_CONTEXT_HOSTNAME:
225 return lttng_add_hostname_to_ctx(ctx);
226 case LTTNG_KERNEL_CONTEXT_CPU_ID:
227 return lttng_add_cpu_id_to_ctx(ctx);
228 case LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE:
229 return lttng_add_interruptible_to_ctx(ctx);
230 case LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE:
231 return lttng_add_need_reschedule_to_ctx(ctx);
232 case LTTNG_KERNEL_CONTEXT_PREEMPTIBLE:
233 return lttng_add_preemptible_to_ctx(ctx);
234 case LTTNG_KERNEL_CONTEXT_MIGRATABLE:
235 return lttng_add_migratable_to_ctx(ctx);
236 case LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL:
237 case LTTNG_KERNEL_CONTEXT_CALLSTACK_USER:
238 return lttng_add_callstack_to_ctx(ctx, context_param->ctx);
239 case LTTNG_KERNEL_CONTEXT_CGROUP_NS:
240 return lttng_add_cgroup_ns_to_ctx(ctx);
241 case LTTNG_KERNEL_CONTEXT_IPC_NS:
242 return lttng_add_ipc_ns_to_ctx(ctx);
243 case LTTNG_KERNEL_CONTEXT_MNT_NS:
244 return lttng_add_mnt_ns_to_ctx(ctx);
245 case LTTNG_KERNEL_CONTEXT_NET_NS:
246 return lttng_add_net_ns_to_ctx(ctx);
247 case LTTNG_KERNEL_CONTEXT_PID_NS:
248 return lttng_add_pid_ns_to_ctx(ctx);
249 case LTTNG_KERNEL_CONTEXT_USER_NS:
250 return lttng_add_user_ns_to_ctx(ctx);
251 case LTTNG_KERNEL_CONTEXT_UTS_NS:
252 return lttng_add_uts_ns_to_ctx(ctx);
253 case LTTNG_KERNEL_CONTEXT_UID:
254 return lttng_add_uid_to_ctx(ctx);
255 case LTTNG_KERNEL_CONTEXT_EUID:
256 return lttng_add_euid_to_ctx(ctx);
257 case LTTNG_KERNEL_CONTEXT_SUID:
258 return lttng_add_suid_to_ctx(ctx);
259 case LTTNG_KERNEL_CONTEXT_GID:
260 return lttng_add_gid_to_ctx(ctx);
261 case LTTNG_KERNEL_CONTEXT_EGID:
262 return lttng_add_egid_to_ctx(ctx);
263 case LTTNG_KERNEL_CONTEXT_SGID:
264 return lttng_add_sgid_to_ctx(ctx);
265 case LTTNG_KERNEL_CONTEXT_VUID:
266 return lttng_add_vuid_to_ctx(ctx);
267 case LTTNG_KERNEL_CONTEXT_VEUID:
268 return lttng_add_veuid_to_ctx(ctx);
269 case LTTNG_KERNEL_CONTEXT_VSUID:
270 return lttng_add_vsuid_to_ctx(ctx);
271 case LTTNG_KERNEL_CONTEXT_VGID:
272 return lttng_add_vgid_to_ctx(ctx);
273 case LTTNG_KERNEL_CONTEXT_VEGID:
274 return lttng_add_vegid_to_ctx(ctx);
275 case LTTNG_KERNEL_CONTEXT_VSGID:
276 return lttng_add_vsgid_to_ctx(ctx);
277 default:
278 return -EINVAL;
279 }
280 }
281
282 /**
283 * lttng_ioctl - lttng syscall through ioctl
284 *
285 * @file: the file
286 * @cmd: the command
287 * @arg: command arg
288 *
289 * This ioctl implements lttng commands:
290 * LTTNG_KERNEL_SESSION
291 * Returns a LTTng trace session file descriptor
292 * LTTNG_KERNEL_TRACER_VERSION
293 * Returns the LTTng kernel tracer version
294 * LTTNG_KERNEL_TRACEPOINT_LIST
295 * Returns a file descriptor listing available tracepoints
296 * LTTNG_KERNEL_WAIT_QUIESCENT
297 * Returns after all previously running probes have completed
298 * LTTNG_KERNEL_TRACER_ABI_VERSION
299 * Returns the LTTng kernel tracer ABI version
300 *
301 * The returned session will be deleted when its file descriptor is closed.
302 */
303 static
304 long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
305 {
306 switch (cmd) {
307 case LTTNG_KERNEL_OLD_SESSION:
308 case LTTNG_KERNEL_SESSION:
309 return lttng_abi_create_session();
310 case LTTNG_KERNEL_OLD_TRACER_VERSION:
311 {
312 struct lttng_kernel_tracer_version v;
313 struct lttng_kernel_old_tracer_version oldv;
314 struct lttng_kernel_old_tracer_version *uversion =
315 (struct lttng_kernel_old_tracer_version __user *) arg;
316
317 lttng_abi_tracer_version(&v);
318 oldv.major = v.major;
319 oldv.minor = v.minor;
320 oldv.patchlevel = v.patchlevel;
321
322 if (copy_to_user(uversion, &oldv, sizeof(oldv)))
323 return -EFAULT;
324 return 0;
325 }
326 case LTTNG_KERNEL_TRACER_VERSION:
327 {
328 struct lttng_kernel_tracer_version version;
329 struct lttng_kernel_tracer_version *uversion =
330 (struct lttng_kernel_tracer_version __user *) arg;
331
332 lttng_abi_tracer_version(&version);
333
334 if (copy_to_user(uversion, &version, sizeof(version)))
335 return -EFAULT;
336 return 0;
337 }
338 case LTTNG_KERNEL_TRACER_ABI_VERSION:
339 {
340 struct lttng_kernel_tracer_abi_version version;
341 struct lttng_kernel_tracer_abi_version *uversion =
342 (struct lttng_kernel_tracer_abi_version __user *) arg;
343
344 lttng_abi_tracer_abi_version(&version);
345
346 if (copy_to_user(uversion, &version, sizeof(version)))
347 return -EFAULT;
348 return 0;
349 }
350 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST:
351 case LTTNG_KERNEL_TRACEPOINT_LIST:
352 return lttng_abi_tracepoint_list();
353 case LTTNG_KERNEL_SYSCALL_LIST:
354 return lttng_abi_syscall_list();
355 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT:
356 case LTTNG_KERNEL_WAIT_QUIESCENT:
357 synchronize_trace();
358 return 0;
359 case LTTNG_KERNEL_OLD_CALIBRATE:
360 {
361 struct lttng_kernel_old_calibrate __user *ucalibrate =
362 (struct lttng_kernel_old_calibrate __user *) arg;
363 struct lttng_kernel_old_calibrate old_calibrate;
364 struct lttng_kernel_calibrate calibrate;
365 int ret;
366
367 if (copy_from_user(&old_calibrate, ucalibrate, sizeof(old_calibrate)))
368 return -EFAULT;
369 calibrate.type = old_calibrate.type;
370 ret = lttng_calibrate(&calibrate);
371 if (copy_to_user(ucalibrate, &old_calibrate, sizeof(old_calibrate)))
372 return -EFAULT;
373 return ret;
374 }
375 case LTTNG_KERNEL_CALIBRATE:
376 {
377 struct lttng_kernel_calibrate __user *ucalibrate =
378 (struct lttng_kernel_calibrate __user *) arg;
379 struct lttng_kernel_calibrate calibrate;
380 int ret;
381
382 if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate)))
383 return -EFAULT;
384 ret = lttng_calibrate(&calibrate);
385 if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate)))
386 return -EFAULT;
387 return ret;
388 }
389 default:
390 return -ENOIOCTLCMD;
391 }
392 }
393
394 static const struct file_operations lttng_fops = {
395 .owner = THIS_MODULE,
396 .unlocked_ioctl = lttng_ioctl,
397 #ifdef CONFIG_COMPAT
398 .compat_ioctl = lttng_ioctl,
399 #endif
400 };
401
402 static
403 int lttng_abi_create_channel(struct file *session_file,
404 struct lttng_kernel_channel *chan_param,
405 enum channel_type channel_type)
406 {
407 struct lttng_session *session = session_file->private_data;
408 const struct file_operations *fops = NULL;
409 const char *transport_name;
410 struct lttng_channel *chan;
411 struct file *chan_file;
412 int chan_fd;
413 int ret = 0;
414
415 chan_fd = lttng_get_unused_fd();
416 if (chan_fd < 0) {
417 ret = chan_fd;
418 goto fd_error;
419 }
420 switch (channel_type) {
421 case PER_CPU_CHANNEL:
422 fops = &lttng_channel_fops;
423 break;
424 case METADATA_CHANNEL:
425 fops = &lttng_metadata_fops;
426 break;
427 }
428
429 chan_file = anon_inode_getfile("[lttng_channel]",
430 fops,
431 NULL, O_RDWR);
432 if (IS_ERR(chan_file)) {
433 ret = PTR_ERR(chan_file);
434 goto file_error;
435 }
436 switch (channel_type) {
437 case PER_CPU_CHANNEL:
438 if (chan_param->output == LTTNG_KERNEL_SPLICE) {
439 transport_name = chan_param->overwrite ?
440 "relay-overwrite" : "relay-discard";
441 } else if (chan_param->output == LTTNG_KERNEL_MMAP) {
442 transport_name = chan_param->overwrite ?
443 "relay-overwrite-mmap" : "relay-discard-mmap";
444 } else {
445 return -EINVAL;
446 }
447 break;
448 case METADATA_CHANNEL:
449 if (chan_param->output == LTTNG_KERNEL_SPLICE)
450 transport_name = "relay-metadata";
451 else if (chan_param->output == LTTNG_KERNEL_MMAP)
452 transport_name = "relay-metadata-mmap";
453 else
454 return -EINVAL;
455 break;
456 default:
457 transport_name = "<unknown>";
458 break;
459 }
460 if (!atomic_long_add_unless(&session_file->f_count, 1, LONG_MAX)) {
461 ret = -EOVERFLOW;
462 goto refcount_error;
463 }
464 /*
465 * We tolerate no failure path after channel creation. It will stay
466 * invariant for the rest of the session.
467 */
468 chan = lttng_channel_create(session, transport_name, NULL,
469 chan_param->subbuf_size,
470 chan_param->num_subbuf,
471 chan_param->switch_timer_interval,
472 chan_param->read_timer_interval,
473 channel_type);
474 if (!chan) {
475 ret = -EINVAL;
476 goto chan_error;
477 }
478 chan->file = chan_file;
479 chan_file->private_data = chan;
480 fd_install(chan_fd, chan_file);
481
482 return chan_fd;
483
484 chan_error:
485 atomic_long_dec(&session_file->f_count);
486 refcount_error:
487 fput(chan_file);
488 file_error:
489 put_unused_fd(chan_fd);
490 fd_error:
491 return ret;
492 }
493
494 static
495 int lttng_abi_session_set_name(struct lttng_session *session,
496 struct lttng_kernel_session_name *name)
497 {
498 size_t len;
499
500 len = strnlen(name->name, LTTNG_KERNEL_SESSION_NAME_LEN);
501
502 if (len == LTTNG_KERNEL_SESSION_NAME_LEN) {
503 /* Name is too long/malformed */
504 return -EINVAL;
505 }
506
507 strcpy(session->name, name->name);
508 return 0;
509 }
510
511 static
512 int lttng_abi_session_set_creation_time(struct lttng_session *session,
513 struct lttng_kernel_session_creation_time *time)
514 {
515 size_t len;
516
517 len = strnlen(time->iso8601, LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN);
518
519 if (len == LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN) {
520 /* Time is too long/malformed */
521 return -EINVAL;
522 }
523
524 strcpy(session->creation_time, time->iso8601);
525 return 0;
526 }
527
528 static
529 enum tracker_type get_tracker_type(struct lttng_kernel_tracker_args *tracker)
530 {
531 switch (tracker->type) {
532 case LTTNG_KERNEL_TRACKER_PID:
533 return TRACKER_PID;
534 case LTTNG_KERNEL_TRACKER_VPID:
535 return TRACKER_VPID;
536 case LTTNG_KERNEL_TRACKER_UID:
537 return TRACKER_UID;
538 case LTTNG_KERNEL_TRACKER_VUID:
539 return TRACKER_VUID;
540 case LTTNG_KERNEL_TRACKER_GID:
541 return TRACKER_GID;
542 case LTTNG_KERNEL_TRACKER_VGID:
543 return TRACKER_VGID;
544 default:
545 return TRACKER_UNKNOWN;
546 }
547 }
548
549 /**
550 * lttng_session_ioctl - lttng session fd ioctl
551 *
552 * @file: the file
553 * @cmd: the command
554 * @arg: command arg
555 *
556 * This ioctl implements lttng commands:
557 * LTTNG_KERNEL_CHANNEL
558 * Returns a LTTng channel file descriptor
559 * LTTNG_KERNEL_ENABLE
560 * Enables tracing for a session (weak enable)
561 * LTTNG_KERNEL_DISABLE
562 * Disables tracing for a session (strong disable)
563 * LTTNG_KERNEL_METADATA
564 * Returns a LTTng metadata file descriptor
565 * LTTNG_KERNEL_SESSION_TRACK_PID
566 * Add PID to session PID tracker
567 * LTTNG_KERNEL_SESSION_UNTRACK_PID
568 * Remove PID from session PID tracker
569 * LTTNG_KERNEL_SESSION_TRACK_ID
570 * Add ID to tracker
571 * LTTNG_KERNEL_SESSION_UNTRACK_ID
572 * Remove ID from tracker
573 *
574 * The returned channel will be deleted when its file descriptor is closed.
575 */
576 static
577 long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
578 {
579 struct lttng_session *session = file->private_data;
580 struct lttng_kernel_channel chan_param;
581 struct lttng_kernel_old_channel old_chan_param;
582
583 switch (cmd) {
584 case LTTNG_KERNEL_OLD_CHANNEL:
585 {
586 if (copy_from_user(&old_chan_param,
587 (struct lttng_kernel_old_channel __user *) arg,
588 sizeof(struct lttng_kernel_old_channel)))
589 return -EFAULT;
590 chan_param.overwrite = old_chan_param.overwrite;
591 chan_param.subbuf_size = old_chan_param.subbuf_size;
592 chan_param.num_subbuf = old_chan_param.num_subbuf;
593 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
594 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
595 chan_param.output = old_chan_param.output;
596
597 return lttng_abi_create_channel(file, &chan_param,
598 PER_CPU_CHANNEL);
599 }
600 case LTTNG_KERNEL_CHANNEL:
601 {
602 if (copy_from_user(&chan_param,
603 (struct lttng_kernel_channel __user *) arg,
604 sizeof(struct lttng_kernel_channel)))
605 return -EFAULT;
606 return lttng_abi_create_channel(file, &chan_param,
607 PER_CPU_CHANNEL);
608 }
609 case LTTNG_KERNEL_OLD_SESSION_START:
610 case LTTNG_KERNEL_OLD_ENABLE:
611 case LTTNG_KERNEL_SESSION_START:
612 case LTTNG_KERNEL_ENABLE:
613 return lttng_session_enable(session);
614 case LTTNG_KERNEL_OLD_SESSION_STOP:
615 case LTTNG_KERNEL_OLD_DISABLE:
616 case LTTNG_KERNEL_SESSION_STOP:
617 case LTTNG_KERNEL_DISABLE:
618 return lttng_session_disable(session);
619 case LTTNG_KERNEL_OLD_METADATA:
620 {
621 if (copy_from_user(&old_chan_param,
622 (struct lttng_kernel_old_channel __user *) arg,
623 sizeof(struct lttng_kernel_old_channel)))
624 return -EFAULT;
625 chan_param.overwrite = old_chan_param.overwrite;
626 chan_param.subbuf_size = old_chan_param.subbuf_size;
627 chan_param.num_subbuf = old_chan_param.num_subbuf;
628 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
629 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
630 chan_param.output = old_chan_param.output;
631
632 return lttng_abi_create_channel(file, &chan_param,
633 METADATA_CHANNEL);
634 }
635 case LTTNG_KERNEL_METADATA:
636 {
637 if (copy_from_user(&chan_param,
638 (struct lttng_kernel_channel __user *) arg,
639 sizeof(struct lttng_kernel_channel)))
640 return -EFAULT;
641 return lttng_abi_create_channel(file, &chan_param,
642 METADATA_CHANNEL);
643 }
644 case LTTNG_KERNEL_SESSION_TRACK_PID:
645 return lttng_session_track_id(session, TRACKER_PID, (int) arg);
646 case LTTNG_KERNEL_SESSION_UNTRACK_PID:
647 return lttng_session_untrack_id(session, TRACKER_PID, (int) arg);
648 case LTTNG_KERNEL_SESSION_TRACK_ID:
649 {
650 struct lttng_kernel_tracker_args tracker;
651 enum tracker_type tracker_type;
652
653 if (copy_from_user(&tracker,
654 (struct lttng_kernel_tracker_args __user *) arg,
655 sizeof(struct lttng_kernel_tracker_args)))
656 return -EFAULT;
657 tracker_type = get_tracker_type(&tracker);
658 if (tracker_type == TRACKER_UNKNOWN)
659 return -EINVAL;
660 return lttng_session_track_id(session, tracker_type, tracker.id);
661 }
662 case LTTNG_KERNEL_SESSION_UNTRACK_ID:
663 {
664 struct lttng_kernel_tracker_args tracker;
665 enum tracker_type tracker_type;
666
667 if (copy_from_user(&tracker,
668 (struct lttng_kernel_tracker_args __user *) arg,
669 sizeof(struct lttng_kernel_tracker_args)))
670 return -EFAULT;
671 tracker_type = get_tracker_type(&tracker);
672 if (tracker_type == TRACKER_UNKNOWN)
673 return -EINVAL;
674 return lttng_session_untrack_id(session, tracker_type,
675 tracker.id);
676 }
677 case LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS:
678 return lttng_session_list_tracker_ids(session, TRACKER_PID);
679 case LTTNG_KERNEL_SESSION_LIST_TRACKER_IDS:
680 {
681 struct lttng_kernel_tracker_args tracker;
682 enum tracker_type tracker_type;
683
684 if (copy_from_user(&tracker,
685 (struct lttng_kernel_tracker_args __user *) arg,
686 sizeof(struct lttng_kernel_tracker_args)))
687 return -EFAULT;
688 tracker_type = get_tracker_type(&tracker);
689 if (tracker_type == TRACKER_UNKNOWN)
690 return -EINVAL;
691 return lttng_session_list_tracker_ids(session, tracker_type);
692 }
693 case LTTNG_KERNEL_SESSION_METADATA_REGEN:
694 return lttng_session_metadata_regenerate(session);
695 case LTTNG_KERNEL_SESSION_STATEDUMP:
696 return lttng_session_statedump(session);
697 case LTTNG_KERNEL_SESSION_SET_NAME:
698 {
699 struct lttng_kernel_session_name name;
700
701 if (copy_from_user(&name,
702 (struct lttng_kernel_session_name __user *) arg,
703 sizeof(struct lttng_kernel_session_name)))
704 return -EFAULT;
705 return lttng_abi_session_set_name(session, &name);
706 }
707 case LTTNG_KERNEL_SESSION_SET_CREATION_TIME:
708 {
709 struct lttng_kernel_session_creation_time time;
710
711 if (copy_from_user(&time,
712 (struct lttng_kernel_session_creation_time __user *) arg,
713 sizeof(struct lttng_kernel_session_creation_time)))
714 return -EFAULT;
715 return lttng_abi_session_set_creation_time(session, &time);
716 }
717 default:
718 return -ENOIOCTLCMD;
719 }
720 }
721
722 /*
723 * Called when the last file reference is dropped.
724 *
725 * Big fat note: channels and events are invariant for the whole session after
726 * their creation. So this session destruction also destroys all channel and
727 * event structures specific to this session (they are not destroyed when their
728 * individual file is released).
729 */
730 static
731 int lttng_session_release(struct inode *inode, struct file *file)
732 {
733 struct lttng_session *session = file->private_data;
734
735 if (session)
736 lttng_session_destroy(session);
737 return 0;
738 }
739
740 static const struct file_operations lttng_session_fops = {
741 .owner = THIS_MODULE,
742 .release = lttng_session_release,
743 .unlocked_ioctl = lttng_session_ioctl,
744 #ifdef CONFIG_COMPAT
745 .compat_ioctl = lttng_session_ioctl,
746 #endif
747 };
748
749 /**
750 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
751 * @filp: the file
752 * @wait: poll table
753 *
754 * Handles the poll operations for the metadata channels.
755 */
756 static
757 unsigned int lttng_metadata_ring_buffer_poll(struct file *filp,
758 poll_table *wait)
759 {
760 struct lttng_metadata_stream *stream = filp->private_data;
761 struct lib_ring_buffer *buf = stream->priv;
762 int finalized;
763 unsigned int mask = 0;
764
765 if (filp->f_mode & FMODE_READ) {
766 poll_wait_set_exclusive(wait);
767 poll_wait(filp, &stream->read_wait, wait);
768
769 finalized = stream->finalized;
770
771 /*
772 * lib_ring_buffer_is_finalized() contains a smp_rmb()
773 * ordering finalized load before offsets loads.
774 */
775 WARN_ON(atomic_long_read(&buf->active_readers) != 1);
776
777 if (finalized)
778 mask |= POLLHUP;
779
780 mutex_lock(&stream->metadata_cache->lock);
781 if (stream->metadata_cache->metadata_written >
782 stream->metadata_out)
783 mask |= POLLIN;
784 mutex_unlock(&stream->metadata_cache->lock);
785 }
786
787 return mask;
788 }
789
790 static
791 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file *filp,
792 unsigned int cmd, unsigned long arg)
793 {
794 struct lttng_metadata_stream *stream = filp->private_data;
795
796 stream->metadata_out = stream->metadata_in;
797 }
798
799 /*
800 * Reset the counter of how much metadata has been consumed to 0. That way,
801 * the consumer receives the content of the metadata cache unchanged. This is
802 * different from the metadata_regenerate where the offset from epoch is
803 * resampled, here we want the exact same content as the last time the metadata
804 * was generated. This command is only possible if all the metadata written
805 * in the cache has been output to the metadata stream to avoid corrupting the
806 * metadata file.
807 *
808 * Return 0 on success, a negative value on error.
809 */
810 static
811 int lttng_metadata_cache_dump(struct lttng_metadata_stream *stream)
812 {
813 int ret;
814 struct lttng_metadata_cache *cache = stream->metadata_cache;
815
816 mutex_lock(&cache->lock);
817 if (stream->metadata_out != cache->metadata_written) {
818 ret = -EBUSY;
819 goto end;
820 }
821 stream->metadata_out = 0;
822 stream->metadata_in = 0;
823 wake_up_interruptible(&stream->read_wait);
824 ret = 0;
825
826 end:
827 mutex_unlock(&cache->lock);
828 return ret;
829 }
830
831 static
832 long lttng_metadata_ring_buffer_ioctl(struct file *filp,
833 unsigned int cmd, unsigned long arg)
834 {
835 int ret;
836 struct lttng_metadata_stream *stream = filp->private_data;
837 struct lib_ring_buffer *buf = stream->priv;
838
839 switch (cmd) {
840 case RING_BUFFER_GET_NEXT_SUBBUF:
841 {
842 struct lttng_metadata_stream *stream = filp->private_data;
843 struct lib_ring_buffer *buf = stream->priv;
844 struct channel *chan = buf->backend.chan;
845
846 ret = lttng_metadata_output_channel(stream, chan);
847 if (ret > 0) {
848 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
849 ret = 0;
850 } else if (ret < 0)
851 goto err;
852 break;
853 }
854 case RING_BUFFER_GET_SUBBUF:
855 {
856 /*
857 * Random access is not allowed for metadata channel.
858 */
859 return -ENOSYS;
860 }
861 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
862 case RING_BUFFER_FLUSH:
863 {
864 struct lttng_metadata_stream *stream = filp->private_data;
865 struct lib_ring_buffer *buf = stream->priv;
866 struct channel *chan = buf->backend.chan;
867
868 /*
869 * Before doing the actual ring buffer flush, write up to one
870 * packet of metadata in the ring buffer.
871 */
872 ret = lttng_metadata_output_channel(stream, chan);
873 if (ret < 0)
874 goto err;
875 break;
876 }
877 case RING_BUFFER_GET_METADATA_VERSION:
878 {
879 struct lttng_metadata_stream *stream = filp->private_data;
880
881 return put_u64(stream->version, arg);
882 }
883 case RING_BUFFER_METADATA_CACHE_DUMP:
884 {
885 struct lttng_metadata_stream *stream = filp->private_data;
886
887 return lttng_metadata_cache_dump(stream);
888 }
889 default:
890 break;
891 }
892 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
893
894 /* Performing lib ring buffer ioctl after our own. */
895 ret = lib_ring_buffer_ioctl(filp, cmd, arg, buf);
896 if (ret < 0)
897 goto err;
898
899 switch (cmd) {
900 case RING_BUFFER_PUT_NEXT_SUBBUF:
901 {
902 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
903 cmd, arg);
904 break;
905 }
906 default:
907 break;
908 }
909 err:
910 return ret;
911 }
912
913 #ifdef CONFIG_COMPAT
914 static
915 long lttng_metadata_ring_buffer_compat_ioctl(struct file *filp,
916 unsigned int cmd, unsigned long arg)
917 {
918 int ret;
919 struct lttng_metadata_stream *stream = filp->private_data;
920 struct lib_ring_buffer *buf = stream->priv;
921
922 switch (cmd) {
923 case RING_BUFFER_GET_NEXT_SUBBUF:
924 {
925 struct lttng_metadata_stream *stream = filp->private_data;
926 struct lib_ring_buffer *buf = stream->priv;
927 struct channel *chan = buf->backend.chan;
928
929 ret = lttng_metadata_output_channel(stream, chan);
930 if (ret > 0) {
931 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
932 ret = 0;
933 } else if (ret < 0)
934 goto err;
935 break;
936 }
937 case RING_BUFFER_GET_SUBBUF:
938 {
939 /*
940 * Random access is not allowed for metadata channel.
941 */
942 return -ENOSYS;
943 }
944 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
945 case RING_BUFFER_FLUSH:
946 {
947 struct lttng_metadata_stream *stream = filp->private_data;
948 struct lib_ring_buffer *buf = stream->priv;
949 struct channel *chan = buf->backend.chan;
950
951 /*
952 * Before doing the actual ring buffer flush, write up to one
953 * packet of metadata in the ring buffer.
954 */
955 ret = lttng_metadata_output_channel(stream, chan);
956 if (ret < 0)
957 goto err;
958 break;
959 }
960 case RING_BUFFER_GET_METADATA_VERSION:
961 {
962 struct lttng_metadata_stream *stream = filp->private_data;
963
964 return put_u64(stream->version, arg);
965 }
966 case RING_BUFFER_METADATA_CACHE_DUMP:
967 {
968 struct lttng_metadata_stream *stream = filp->private_data;
969
970 return lttng_metadata_cache_dump(stream);
971 }
972 default:
973 break;
974 }
975 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
976
977 /* Performing lib ring buffer ioctl after our own. */
978 ret = lib_ring_buffer_compat_ioctl(filp, cmd, arg, buf);
979 if (ret < 0)
980 goto err;
981
982 switch (cmd) {
983 case RING_BUFFER_PUT_NEXT_SUBBUF:
984 {
985 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
986 cmd, arg);
987 break;
988 }
989 default:
990 break;
991 }
992 err:
993 return ret;
994 }
995 #endif
996
997 /*
998 * This is not used by anonymous file descriptors. This code is left
999 * there if we ever want to implement an inode with open() operation.
1000 */
1001 static
1002 int lttng_metadata_ring_buffer_open(struct inode *inode, struct file *file)
1003 {
1004 struct lttng_metadata_stream *stream = inode->i_private;
1005 struct lib_ring_buffer *buf = stream->priv;
1006
1007 file->private_data = buf;
1008 /*
1009 * Since life-time of metadata cache differs from that of
1010 * session, we need to keep our own reference on the transport.
1011 */
1012 if (!try_module_get(stream->transport->owner)) {
1013 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
1014 return -EBUSY;
1015 }
1016 return lib_ring_buffer_open(inode, file, buf);
1017 }
1018
1019 static
1020 int lttng_metadata_ring_buffer_release(struct inode *inode, struct file *file)
1021 {
1022 struct lttng_metadata_stream *stream = file->private_data;
1023 struct lib_ring_buffer *buf = stream->priv;
1024
1025 kref_put(&stream->metadata_cache->refcount, metadata_cache_destroy);
1026 module_put(stream->transport->owner);
1027 return lib_ring_buffer_release(inode, file, buf);
1028 }
1029
1030 static
1031 ssize_t lttng_metadata_ring_buffer_splice_read(struct file *in, loff_t *ppos,
1032 struct pipe_inode_info *pipe, size_t len,
1033 unsigned int flags)
1034 {
1035 struct lttng_metadata_stream *stream = in->private_data;
1036 struct lib_ring_buffer *buf = stream->priv;
1037
1038 return lib_ring_buffer_splice_read(in, ppos, pipe, len,
1039 flags, buf);
1040 }
1041
1042 static
1043 int lttng_metadata_ring_buffer_mmap(struct file *filp,
1044 struct vm_area_struct *vma)
1045 {
1046 struct lttng_metadata_stream *stream = filp->private_data;
1047 struct lib_ring_buffer *buf = stream->priv;
1048
1049 return lib_ring_buffer_mmap(filp, vma, buf);
1050 }
1051
1052 static
1053 const struct file_operations lttng_metadata_ring_buffer_file_operations = {
1054 .owner = THIS_MODULE,
1055 .open = lttng_metadata_ring_buffer_open,
1056 .release = lttng_metadata_ring_buffer_release,
1057 .poll = lttng_metadata_ring_buffer_poll,
1058 .splice_read = lttng_metadata_ring_buffer_splice_read,
1059 .mmap = lttng_metadata_ring_buffer_mmap,
1060 .unlocked_ioctl = lttng_metadata_ring_buffer_ioctl,
1061 .llseek = vfs_lib_ring_buffer_no_llseek,
1062 #ifdef CONFIG_COMPAT
1063 .compat_ioctl = lttng_metadata_ring_buffer_compat_ioctl,
1064 #endif
1065 };
1066
1067 static
1068 int lttng_abi_create_stream_fd(struct file *channel_file, void *stream_priv,
1069 const struct file_operations *fops)
1070 {
1071 int stream_fd, ret;
1072 struct file *stream_file;
1073
1074 stream_fd = lttng_get_unused_fd();
1075 if (stream_fd < 0) {
1076 ret = stream_fd;
1077 goto fd_error;
1078 }
1079 stream_file = anon_inode_getfile("[lttng_stream]", fops,
1080 stream_priv, O_RDWR);
1081 if (IS_ERR(stream_file)) {
1082 ret = PTR_ERR(stream_file);
1083 goto file_error;
1084 }
1085 /*
1086 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
1087 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
1088 * file descriptor, so we set FMODE_PREAD here.
1089 */
1090 stream_file->f_mode |= FMODE_PREAD;
1091 fd_install(stream_fd, stream_file);
1092 /*
1093 * The stream holds a reference to the channel within the generic ring
1094 * buffer library, so no need to hold a refcount on the channel and
1095 * session files here.
1096 */
1097 return stream_fd;
1098
1099 file_error:
1100 put_unused_fd(stream_fd);
1101 fd_error:
1102 return ret;
1103 }
1104
1105 static
1106 int lttng_abi_open_stream(struct file *channel_file)
1107 {
1108 struct lttng_channel *channel = channel_file->private_data;
1109 struct lib_ring_buffer *buf;
1110 int ret;
1111 void *stream_priv;
1112
1113 buf = channel->ops->buffer_read_open(channel->chan);
1114 if (!buf)
1115 return -ENOENT;
1116
1117 stream_priv = buf;
1118 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
1119 &lttng_stream_ring_buffer_file_operations);
1120 if (ret < 0)
1121 goto fd_error;
1122
1123 return ret;
1124
1125 fd_error:
1126 channel->ops->buffer_read_close(buf);
1127 return ret;
1128 }
1129
1130 static
1131 int lttng_abi_open_metadata_stream(struct file *channel_file)
1132 {
1133 struct lttng_channel *channel = channel_file->private_data;
1134 struct lttng_session *session = channel->session;
1135 struct lib_ring_buffer *buf;
1136 int ret;
1137 struct lttng_metadata_stream *metadata_stream;
1138 void *stream_priv;
1139
1140 buf = channel->ops->buffer_read_open(channel->chan);
1141 if (!buf)
1142 return -ENOENT;
1143
1144 metadata_stream = kzalloc(sizeof(struct lttng_metadata_stream),
1145 GFP_KERNEL);
1146 if (!metadata_stream) {
1147 ret = -ENOMEM;
1148 goto nomem;
1149 }
1150 metadata_stream->metadata_cache = session->metadata_cache;
1151 init_waitqueue_head(&metadata_stream->read_wait);
1152 metadata_stream->priv = buf;
1153 stream_priv = metadata_stream;
1154 metadata_stream->transport = channel->transport;
1155
1156 /*
1157 * Since life-time of metadata cache differs from that of
1158 * session, we need to keep our own reference on the transport.
1159 */
1160 if (!try_module_get(metadata_stream->transport->owner)) {
1161 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
1162 ret = -EINVAL;
1163 goto notransport;
1164 }
1165
1166 if (!lttng_kref_get(&session->metadata_cache->refcount)) {
1167 ret = -EOVERFLOW;
1168 goto kref_error;
1169 }
1170
1171 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
1172 &lttng_metadata_ring_buffer_file_operations);
1173 if (ret < 0)
1174 goto fd_error;
1175
1176 list_add(&metadata_stream->list,
1177 &session->metadata_cache->metadata_stream);
1178 return ret;
1179
1180 fd_error:
1181 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
1182 kref_error:
1183 module_put(metadata_stream->transport->owner);
1184 notransport:
1185 kfree(metadata_stream);
1186 nomem:
1187 channel->ops->buffer_read_close(buf);
1188 return ret;
1189 }
1190
1191 static
1192 int lttng_abi_create_event(struct file *channel_file,
1193 struct lttng_kernel_event *event_param)
1194 {
1195 struct lttng_channel *channel = channel_file->private_data;
1196 int event_fd, ret;
1197 struct file *event_file;
1198 void *priv;
1199
1200 event_param->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1201 switch (event_param->instrumentation) {
1202 case LTTNG_KERNEL_KRETPROBE:
1203 event_param->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1204 break;
1205 case LTTNG_KERNEL_KPROBE:
1206 event_param->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1207 break;
1208 case LTTNG_KERNEL_FUNCTION:
1209 event_param->u.ftrace.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1210 break;
1211 default:
1212 break;
1213 }
1214 event_fd = lttng_get_unused_fd();
1215 if (event_fd < 0) {
1216 ret = event_fd;
1217 goto fd_error;
1218 }
1219 event_file = anon_inode_getfile("[lttng_event]",
1220 &lttng_event_fops,
1221 NULL, O_RDWR);
1222 if (IS_ERR(event_file)) {
1223 ret = PTR_ERR(event_file);
1224 goto file_error;
1225 }
1226 /* The event holds a reference on the channel */
1227 if (!atomic_long_add_unless(&channel_file->f_count, 1, LONG_MAX)) {
1228 ret = -EOVERFLOW;
1229 goto refcount_error;
1230 }
1231 if (event_param->instrumentation == LTTNG_KERNEL_TRACEPOINT
1232 || event_param->instrumentation == LTTNG_KERNEL_SYSCALL) {
1233 struct lttng_enabler *enabler;
1234
1235 if (strutils_is_star_glob_pattern(event_param->name)) {
1236 /*
1237 * If the event name is a star globbing pattern,
1238 * we create the special star globbing enabler.
1239 */
1240 enabler = lttng_enabler_create(LTTNG_ENABLER_STAR_GLOB,
1241 event_param, channel);
1242 } else {
1243 enabler = lttng_enabler_create(LTTNG_ENABLER_NAME,
1244 event_param, channel);
1245 }
1246 priv = enabler;
1247 } else {
1248 struct lttng_event *event;
1249
1250 /*
1251 * We tolerate no failure path after event creation. It
1252 * will stay invariant for the rest of the session.
1253 */
1254 event = lttng_event_create(channel, event_param,
1255 NULL, NULL,
1256 event_param->instrumentation);
1257 WARN_ON_ONCE(!event);
1258 if (IS_ERR(event)) {
1259 ret = PTR_ERR(event);
1260 goto event_error;
1261 }
1262 priv = event;
1263 }
1264 event_file->private_data = priv;
1265 fd_install(event_fd, event_file);
1266 return event_fd;
1267
1268 event_error:
1269 atomic_long_dec(&channel_file->f_count);
1270 refcount_error:
1271 fput(event_file);
1272 file_error:
1273 put_unused_fd(event_fd);
1274 fd_error:
1275 return ret;
1276 }
1277
1278 /**
1279 * lttng_channel_ioctl - lttng syscall through ioctl
1280 *
1281 * @file: the file
1282 * @cmd: the command
1283 * @arg: command arg
1284 *
1285 * This ioctl implements lttng commands:
1286 * LTTNG_KERNEL_STREAM
1287 * Returns an event stream file descriptor or failure.
1288 * (typically, one event stream records events from one CPU)
1289 * LTTNG_KERNEL_EVENT
1290 * Returns an event file descriptor or failure.
1291 * LTTNG_KERNEL_CONTEXT
1292 * Prepend a context field to each event in the channel
1293 * LTTNG_KERNEL_ENABLE
1294 * Enable recording for events in this channel (weak enable)
1295 * LTTNG_KERNEL_DISABLE
1296 * Disable recording for events in this channel (strong disable)
1297 *
1298 * Channel and event file descriptors also hold a reference on the session.
1299 */
1300 static
1301 long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1302 {
1303 struct lttng_channel *channel = file->private_data;
1304
1305 switch (cmd) {
1306 case LTTNG_KERNEL_OLD_STREAM:
1307 case LTTNG_KERNEL_STREAM:
1308 return lttng_abi_open_stream(file);
1309 case LTTNG_KERNEL_OLD_EVENT:
1310 {
1311 struct lttng_kernel_event *uevent_param;
1312 struct lttng_kernel_old_event *old_uevent_param;
1313 int ret;
1314
1315 uevent_param = kmalloc(sizeof(struct lttng_kernel_event),
1316 GFP_KERNEL);
1317 if (!uevent_param) {
1318 ret = -ENOMEM;
1319 goto old_event_end;
1320 }
1321 old_uevent_param = kmalloc(
1322 sizeof(struct lttng_kernel_old_event),
1323 GFP_KERNEL);
1324 if (!old_uevent_param) {
1325 ret = -ENOMEM;
1326 goto old_event_error_free_param;
1327 }
1328 if (copy_from_user(old_uevent_param,
1329 (struct lttng_kernel_old_event __user *) arg,
1330 sizeof(struct lttng_kernel_old_event))) {
1331 ret = -EFAULT;
1332 goto old_event_error_free_old_param;
1333 }
1334
1335 memcpy(uevent_param->name, old_uevent_param->name,
1336 sizeof(uevent_param->name));
1337 uevent_param->instrumentation =
1338 old_uevent_param->instrumentation;
1339
1340 switch (old_uevent_param->instrumentation) {
1341 case LTTNG_KERNEL_KPROBE:
1342 uevent_param->u.kprobe.addr =
1343 old_uevent_param->u.kprobe.addr;
1344 uevent_param->u.kprobe.offset =
1345 old_uevent_param->u.kprobe.offset;
1346 memcpy(uevent_param->u.kprobe.symbol_name,
1347 old_uevent_param->u.kprobe.symbol_name,
1348 sizeof(uevent_param->u.kprobe.symbol_name));
1349 break;
1350 case LTTNG_KERNEL_KRETPROBE:
1351 uevent_param->u.kretprobe.addr =
1352 old_uevent_param->u.kretprobe.addr;
1353 uevent_param->u.kretprobe.offset =
1354 old_uevent_param->u.kretprobe.offset;
1355 memcpy(uevent_param->u.kretprobe.symbol_name,
1356 old_uevent_param->u.kretprobe.symbol_name,
1357 sizeof(uevent_param->u.kretprobe.symbol_name));
1358 break;
1359 case LTTNG_KERNEL_FUNCTION:
1360 memcpy(uevent_param->u.ftrace.symbol_name,
1361 old_uevent_param->u.ftrace.symbol_name,
1362 sizeof(uevent_param->u.ftrace.symbol_name));
1363 break;
1364 default:
1365 break;
1366 }
1367 ret = lttng_abi_create_event(file, uevent_param);
1368
1369 old_event_error_free_old_param:
1370 kfree(old_uevent_param);
1371 old_event_error_free_param:
1372 kfree(uevent_param);
1373 old_event_end:
1374 return ret;
1375 }
1376 case LTTNG_KERNEL_EVENT:
1377 {
1378 struct lttng_kernel_event uevent_param;
1379
1380 if (copy_from_user(&uevent_param,
1381 (struct lttng_kernel_event __user *) arg,
1382 sizeof(uevent_param)))
1383 return -EFAULT;
1384 return lttng_abi_create_event(file, &uevent_param);
1385 }
1386 case LTTNG_KERNEL_OLD_CONTEXT:
1387 {
1388 struct lttng_kernel_context *ucontext_param;
1389 struct lttng_kernel_old_context *old_ucontext_param;
1390 int ret;
1391
1392 ucontext_param = kmalloc(sizeof(struct lttng_kernel_context),
1393 GFP_KERNEL);
1394 if (!ucontext_param) {
1395 ret = -ENOMEM;
1396 goto old_ctx_end;
1397 }
1398 old_ucontext_param = kmalloc(sizeof(struct lttng_kernel_old_context),
1399 GFP_KERNEL);
1400 if (!old_ucontext_param) {
1401 ret = -ENOMEM;
1402 goto old_ctx_error_free_param;
1403 }
1404
1405 if (copy_from_user(old_ucontext_param,
1406 (struct lttng_kernel_old_context __user *) arg,
1407 sizeof(struct lttng_kernel_old_context))) {
1408 ret = -EFAULT;
1409 goto old_ctx_error_free_old_param;
1410 }
1411 ucontext_param->ctx = old_ucontext_param->ctx;
1412 memcpy(ucontext_param->padding, old_ucontext_param->padding,
1413 sizeof(ucontext_param->padding));
1414 /* only type that uses the union */
1415 if (old_ucontext_param->ctx == LTTNG_KERNEL_CONTEXT_PERF_COUNTER) {
1416 ucontext_param->u.perf_counter.type =
1417 old_ucontext_param->u.perf_counter.type;
1418 ucontext_param->u.perf_counter.config =
1419 old_ucontext_param->u.perf_counter.config;
1420 memcpy(ucontext_param->u.perf_counter.name,
1421 old_ucontext_param->u.perf_counter.name,
1422 sizeof(ucontext_param->u.perf_counter.name));
1423 }
1424
1425 ret = lttng_abi_add_context(file,
1426 ucontext_param,
1427 &channel->ctx, channel->session);
1428
1429 old_ctx_error_free_old_param:
1430 kfree(old_ucontext_param);
1431 old_ctx_error_free_param:
1432 kfree(ucontext_param);
1433 old_ctx_end:
1434 return ret;
1435 }
1436 case LTTNG_KERNEL_CONTEXT:
1437 {
1438 struct lttng_kernel_context ucontext_param;
1439
1440 if (copy_from_user(&ucontext_param,
1441 (struct lttng_kernel_context __user *) arg,
1442 sizeof(ucontext_param)))
1443 return -EFAULT;
1444 return lttng_abi_add_context(file,
1445 &ucontext_param,
1446 &channel->ctx, channel->session);
1447 }
1448 case LTTNG_KERNEL_OLD_ENABLE:
1449 case LTTNG_KERNEL_ENABLE:
1450 return lttng_channel_enable(channel);
1451 case LTTNG_KERNEL_OLD_DISABLE:
1452 case LTTNG_KERNEL_DISABLE:
1453 return lttng_channel_disable(channel);
1454 case LTTNG_KERNEL_SYSCALL_MASK:
1455 return lttng_channel_syscall_mask(channel,
1456 (struct lttng_kernel_syscall_mask __user *) arg);
1457 default:
1458 return -ENOIOCTLCMD;
1459 }
1460 }
1461
1462 /**
1463 * lttng_metadata_ioctl - lttng syscall through ioctl
1464 *
1465 * @file: the file
1466 * @cmd: the command
1467 * @arg: command arg
1468 *
1469 * This ioctl implements lttng commands:
1470 * LTTNG_KERNEL_STREAM
1471 * Returns an event stream file descriptor or failure.
1472 *
1473 * Channel and event file descriptors also hold a reference on the session.
1474 */
1475 static
1476 long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1477 {
1478 switch (cmd) {
1479 case LTTNG_KERNEL_OLD_STREAM:
1480 case LTTNG_KERNEL_STREAM:
1481 return lttng_abi_open_metadata_stream(file);
1482 default:
1483 return -ENOIOCTLCMD;
1484 }
1485 }
1486
1487 /**
1488 * lttng_channel_poll - lttng stream addition/removal monitoring
1489 *
1490 * @file: the file
1491 * @wait: poll table
1492 */
1493 unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
1494 {
1495 struct lttng_channel *channel = file->private_data;
1496 unsigned int mask = 0;
1497
1498 if (file->f_mode & FMODE_READ) {
1499 poll_wait_set_exclusive(wait);
1500 poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
1501 wait);
1502
1503 if (channel->ops->is_disabled(channel->chan))
1504 return POLLERR;
1505 if (channel->ops->is_finalized(channel->chan))
1506 return POLLHUP;
1507 if (channel->ops->buffer_has_read_closed_stream(channel->chan))
1508 return POLLIN | POLLRDNORM;
1509 return 0;
1510 }
1511 return mask;
1512
1513 }
1514
1515 static
1516 int lttng_channel_release(struct inode *inode, struct file *file)
1517 {
1518 struct lttng_channel *channel = file->private_data;
1519
1520 if (channel)
1521 fput(channel->session->file);
1522 return 0;
1523 }
1524
1525 static
1526 int lttng_metadata_channel_release(struct inode *inode, struct file *file)
1527 {
1528 struct lttng_channel *channel = file->private_data;
1529
1530 if (channel) {
1531 fput(channel->session->file);
1532 lttng_metadata_channel_destroy(channel);
1533 }
1534
1535 return 0;
1536 }
1537
1538 static const struct file_operations lttng_channel_fops = {
1539 .owner = THIS_MODULE,
1540 .release = lttng_channel_release,
1541 .poll = lttng_channel_poll,
1542 .unlocked_ioctl = lttng_channel_ioctl,
1543 #ifdef CONFIG_COMPAT
1544 .compat_ioctl = lttng_channel_ioctl,
1545 #endif
1546 };
1547
1548 static const struct file_operations lttng_metadata_fops = {
1549 .owner = THIS_MODULE,
1550 .release = lttng_metadata_channel_release,
1551 .unlocked_ioctl = lttng_metadata_ioctl,
1552 #ifdef CONFIG_COMPAT
1553 .compat_ioctl = lttng_metadata_ioctl,
1554 #endif
1555 };
1556
1557 /**
1558 * lttng_event_ioctl - lttng syscall through ioctl
1559 *
1560 * @file: the file
1561 * @cmd: the command
1562 * @arg: command arg
1563 *
1564 * This ioctl implements lttng commands:
1565 * LTTNG_KERNEL_CONTEXT
1566 * Prepend a context field to each record of this event
1567 * LTTNG_KERNEL_ENABLE
1568 * Enable recording for this event (weak enable)
1569 * LTTNG_KERNEL_DISABLE
1570 * Disable recording for this event (strong disable)
1571 */
1572 static
1573 long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1574 {
1575 struct lttng_event *event;
1576 struct lttng_enabler *enabler;
1577 enum lttng_event_type *evtype = file->private_data;
1578
1579 switch (cmd) {
1580 case LTTNG_KERNEL_OLD_CONTEXT:
1581 {
1582 /* Not implemented */
1583 return -ENOSYS;
1584 }
1585 case LTTNG_KERNEL_CONTEXT:
1586 {
1587 /* Not implemented */
1588 return -ENOSYS;
1589 }
1590 case LTTNG_KERNEL_OLD_ENABLE:
1591 case LTTNG_KERNEL_ENABLE:
1592 switch (*evtype) {
1593 case LTTNG_TYPE_EVENT:
1594 event = file->private_data;
1595 return lttng_event_enable(event);
1596 case LTTNG_TYPE_ENABLER:
1597 enabler = file->private_data;
1598 return lttng_enabler_enable(enabler);
1599 default:
1600 WARN_ON_ONCE(1);
1601 return -ENOSYS;
1602 }
1603 case LTTNG_KERNEL_OLD_DISABLE:
1604 case LTTNG_KERNEL_DISABLE:
1605 switch (*evtype) {
1606 case LTTNG_TYPE_EVENT:
1607 event = file->private_data;
1608 return lttng_event_disable(event);
1609 case LTTNG_TYPE_ENABLER:
1610 enabler = file->private_data;
1611 return lttng_enabler_disable(enabler);
1612 default:
1613 WARN_ON_ONCE(1);
1614 return -ENOSYS;
1615 }
1616 case LTTNG_KERNEL_FILTER:
1617 switch (*evtype) {
1618 case LTTNG_TYPE_EVENT:
1619 return -EINVAL;
1620 case LTTNG_TYPE_ENABLER:
1621 {
1622 enabler = file->private_data;
1623 return lttng_enabler_attach_bytecode(enabler,
1624 (struct lttng_kernel_filter_bytecode __user *) arg);
1625 }
1626 default:
1627 WARN_ON_ONCE(1);
1628 return -ENOSYS;
1629 }
1630 case LTTNG_KERNEL_ADD_CALLSITE:
1631 switch (*evtype) {
1632 case LTTNG_TYPE_EVENT:
1633 event = file->private_data;
1634 return lttng_event_add_callsite(event,
1635 (struct lttng_kernel_event_callsite __user *) arg);
1636 case LTTNG_TYPE_ENABLER:
1637 return -EINVAL;
1638 default:
1639 WARN_ON_ONCE(1);
1640 return -ENOSYS;
1641 }
1642 default:
1643 return -ENOIOCTLCMD;
1644 }
1645 }
1646
1647 static
1648 int lttng_event_release(struct inode *inode, struct file *file)
1649 {
1650 struct lttng_event *event;
1651 struct lttng_enabler *enabler;
1652 enum lttng_event_type *evtype = file->private_data;
1653
1654 if (!evtype)
1655 return 0;
1656
1657 switch (*evtype) {
1658 case LTTNG_TYPE_EVENT:
1659 event = file->private_data;
1660 if (event)
1661 fput(event->chan->file);
1662 break;
1663 case LTTNG_TYPE_ENABLER:
1664 enabler = file->private_data;
1665 if (enabler)
1666 fput(enabler->chan->file);
1667 break;
1668 default:
1669 WARN_ON_ONCE(1);
1670 break;
1671 }
1672
1673 return 0;
1674 }
1675
1676 /* TODO: filter control ioctl */
1677 static const struct file_operations lttng_event_fops = {
1678 .owner = THIS_MODULE,
1679 .release = lttng_event_release,
1680 .unlocked_ioctl = lttng_event_ioctl,
1681 #ifdef CONFIG_COMPAT
1682 .compat_ioctl = lttng_event_ioctl,
1683 #endif
1684 };
1685
1686 static int put_u64(uint64_t val, unsigned long arg)
1687 {
1688 return put_user(val, (uint64_t __user *) arg);
1689 }
1690
1691 static long lttng_stream_ring_buffer_ioctl(struct file *filp,
1692 unsigned int cmd, unsigned long arg)
1693 {
1694 struct lib_ring_buffer *buf = filp->private_data;
1695 struct channel *chan = buf->backend.chan;
1696 const struct lib_ring_buffer_config *config = &chan->backend.config;
1697 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
1698 int ret;
1699
1700 if (atomic_read(&chan->record_disabled))
1701 return -EIO;
1702
1703 switch (cmd) {
1704 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN:
1705 {
1706 uint64_t ts;
1707
1708 ret = ops->timestamp_begin(config, buf, &ts);
1709 if (ret < 0)
1710 goto error;
1711 return put_u64(ts, arg);
1712 }
1713 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END:
1714 {
1715 uint64_t ts;
1716
1717 ret = ops->timestamp_end(config, buf, &ts);
1718 if (ret < 0)
1719 goto error;
1720 return put_u64(ts, arg);
1721 }
1722 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED:
1723 {
1724 uint64_t ed;
1725
1726 ret = ops->events_discarded(config, buf, &ed);
1727 if (ret < 0)
1728 goto error;
1729 return put_u64(ed, arg);
1730 }
1731 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE:
1732 {
1733 uint64_t cs;
1734
1735 ret = ops->content_size(config, buf, &cs);
1736 if (ret < 0)
1737 goto error;
1738 return put_u64(cs, arg);
1739 }
1740 case LTTNG_RING_BUFFER_GET_PACKET_SIZE:
1741 {
1742 uint64_t ps;
1743
1744 ret = ops->packet_size(config, buf, &ps);
1745 if (ret < 0)
1746 goto error;
1747 return put_u64(ps, arg);
1748 }
1749 case LTTNG_RING_BUFFER_GET_STREAM_ID:
1750 {
1751 uint64_t si;
1752
1753 ret = ops->stream_id(config, buf, &si);
1754 if (ret < 0)
1755 goto error;
1756 return put_u64(si, arg);
1757 }
1758 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
1759 {
1760 uint64_t ts;
1761
1762 ret = ops->current_timestamp(config, buf, &ts);
1763 if (ret < 0)
1764 goto error;
1765 return put_u64(ts, arg);
1766 }
1767 case LTTNG_RING_BUFFER_GET_SEQ_NUM:
1768 {
1769 uint64_t seq;
1770
1771 ret = ops->sequence_number(config, buf, &seq);
1772 if (ret < 0)
1773 goto error;
1774 return put_u64(seq, arg);
1775 }
1776 case LTTNG_RING_BUFFER_INSTANCE_ID:
1777 {
1778 uint64_t id;
1779
1780 ret = ops->instance_id(config, buf, &id);
1781 if (ret < 0)
1782 goto error;
1783 return put_u64(id, arg);
1784 }
1785 default:
1786 return lib_ring_buffer_file_operations.unlocked_ioctl(filp,
1787 cmd, arg);
1788 }
1789
1790 error:
1791 return -ENOSYS;
1792 }
1793
1794 #ifdef CONFIG_COMPAT
1795 static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
1796 unsigned int cmd, unsigned long arg)
1797 {
1798 struct lib_ring_buffer *buf = filp->private_data;
1799 struct channel *chan = buf->backend.chan;
1800 const struct lib_ring_buffer_config *config = &chan->backend.config;
1801 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
1802 int ret;
1803
1804 if (atomic_read(&chan->record_disabled))
1805 return -EIO;
1806
1807 switch (cmd) {
1808 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN:
1809 {
1810 uint64_t ts;
1811
1812 ret = ops->timestamp_begin(config, buf, &ts);
1813 if (ret < 0)
1814 goto error;
1815 return put_u64(ts, arg);
1816 }
1817 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END:
1818 {
1819 uint64_t ts;
1820
1821 ret = ops->timestamp_end(config, buf, &ts);
1822 if (ret < 0)
1823 goto error;
1824 return put_u64(ts, arg);
1825 }
1826 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED:
1827 {
1828 uint64_t ed;
1829
1830 ret = ops->events_discarded(config, buf, &ed);
1831 if (ret < 0)
1832 goto error;
1833 return put_u64(ed, arg);
1834 }
1835 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE:
1836 {
1837 uint64_t cs;
1838
1839 ret = ops->content_size(config, buf, &cs);
1840 if (ret < 0)
1841 goto error;
1842 return put_u64(cs, arg);
1843 }
1844 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE:
1845 {
1846 uint64_t ps;
1847
1848 ret = ops->packet_size(config, buf, &ps);
1849 if (ret < 0)
1850 goto error;
1851 return put_u64(ps, arg);
1852 }
1853 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID:
1854 {
1855 uint64_t si;
1856
1857 ret = ops->stream_id(config, buf, &si);
1858 if (ret < 0)
1859 goto error;
1860 return put_u64(si, arg);
1861 }
1862 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
1863 {
1864 uint64_t ts;
1865
1866 ret = ops->current_timestamp(config, buf, &ts);
1867 if (ret < 0)
1868 goto error;
1869 return put_u64(ts, arg);
1870 }
1871 case LTTNG_RING_BUFFER_COMPAT_GET_SEQ_NUM:
1872 {
1873 uint64_t seq;
1874
1875 ret = ops->sequence_number(config, buf, &seq);
1876 if (ret < 0)
1877 goto error;
1878 return put_u64(seq, arg);
1879 }
1880 case LTTNG_RING_BUFFER_COMPAT_INSTANCE_ID:
1881 {
1882 uint64_t id;
1883
1884 ret = ops->instance_id(config, buf, &id);
1885 if (ret < 0)
1886 goto error;
1887 return put_u64(id, arg);
1888 }
1889 default:
1890 return lib_ring_buffer_file_operations.compat_ioctl(filp,
1891 cmd, arg);
1892 }
1893
1894 error:
1895 return -ENOSYS;
1896 }
1897 #endif /* CONFIG_COMPAT */
1898
1899 static void lttng_stream_override_ring_buffer_fops(void)
1900 {
1901 lttng_stream_ring_buffer_file_operations.owner = THIS_MODULE;
1902 lttng_stream_ring_buffer_file_operations.open =
1903 lib_ring_buffer_file_operations.open;
1904 lttng_stream_ring_buffer_file_operations.release =
1905 lib_ring_buffer_file_operations.release;
1906 lttng_stream_ring_buffer_file_operations.poll =
1907 lib_ring_buffer_file_operations.poll;
1908 lttng_stream_ring_buffer_file_operations.splice_read =
1909 lib_ring_buffer_file_operations.splice_read;
1910 lttng_stream_ring_buffer_file_operations.mmap =
1911 lib_ring_buffer_file_operations.mmap;
1912 lttng_stream_ring_buffer_file_operations.unlocked_ioctl =
1913 lttng_stream_ring_buffer_ioctl;
1914 lttng_stream_ring_buffer_file_operations.llseek =
1915 lib_ring_buffer_file_operations.llseek;
1916 #ifdef CONFIG_COMPAT
1917 lttng_stream_ring_buffer_file_operations.compat_ioctl =
1918 lttng_stream_ring_buffer_compat_ioctl;
1919 #endif
1920 }
1921
1922 int __init lttng_abi_init(void)
1923 {
1924 int ret = 0;
1925
1926 wrapper_vmalloc_sync_all();
1927 lttng_clock_ref();
1928
1929 ret = lttng_tp_mempool_init();
1930 if (ret) {
1931 goto error;
1932 }
1933
1934 lttng_proc_dentry = proc_create_data("lttng", S_IRUSR | S_IWUSR, NULL,
1935 &lttng_fops, NULL);
1936
1937 if (!lttng_proc_dentry) {
1938 printk(KERN_ERR "Error creating LTTng control file\n");
1939 ret = -ENOMEM;
1940 goto error;
1941 }
1942 lttng_stream_override_ring_buffer_fops();
1943 return 0;
1944
1945 error:
1946 lttng_tp_mempool_destroy();
1947 lttng_clock_unref();
1948 return ret;
1949 }
1950
1951 /* No __exit annotation because used by init error path too. */
1952 void lttng_abi_exit(void)
1953 {
1954 lttng_tp_mempool_destroy();
1955 lttng_clock_unref();
1956 if (lttng_proc_dentry)
1957 remove_proc_entry("lttng", NULL);
1958 }
LTTng 2.0/0.x modules
This page took 0.094521 seconds and 5 git commands to generate.