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[lttng-modules.git] / src / lttng-abi.c
1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
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_mappings() */
34 #include <ringbuffer/vfs.h>
35 #include <ringbuffer/backend.h>
36 #include <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 <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
55 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
56 static const struct proc_ops lttng_proc_ops;
57 #else
58 static const struct file_operations lttng_proc_ops;
59 #endif
60
61 static const struct file_operations lttng_session_fops;
62 static const struct file_operations lttng_event_notifier_group_fops;
63 static const struct file_operations lttng_channel_fops;
64 static const struct file_operations lttng_metadata_fops;
65 static const struct file_operations lttng_event_fops;
66 static struct file_operations lttng_stream_ring_buffer_file_operations;
67
68 static int put_u64(uint64_t val, unsigned long arg);
69 static int put_u32(uint32_t val, unsigned long arg);
70
71 /*
72 * Teardown management: opened file descriptors keep a refcount on the module,
73 * so it can only exit when all file descriptors are closed.
74 */
75
76 static
77 int lttng_abi_create_session(void)
78 {
79 struct lttng_session *session;
80 struct file *session_file;
81 int session_fd, ret;
82
83 session = lttng_session_create();
84 if (!session)
85 return -ENOMEM;
86 session_fd = lttng_get_unused_fd();
87 if (session_fd < 0) {
88 ret = session_fd;
89 goto fd_error;
90 }
91 session_file = anon_inode_getfile("[lttng_session]",
92 &lttng_session_fops,
93 session, O_RDWR);
94 if (IS_ERR(session_file)) {
95 ret = PTR_ERR(session_file);
96 goto file_error;
97 }
98 session->file = session_file;
99 fd_install(session_fd, session_file);
100 return session_fd;
101
102 file_error:
103 put_unused_fd(session_fd);
104 fd_error:
105 lttng_session_destroy(session);
106 return ret;
107 }
108
109 static
110 int lttng_abi_create_event_notifier_group(void)
111 {
112 struct lttng_event_notifier_group *event_notifier_group;
113 struct file *event_notifier_group_file;
114 int event_notifier_group_fd, ret;
115
116 event_notifier_group = lttng_event_notifier_group_create();
117 if (!event_notifier_group)
118 return -ENOMEM;
119
120 event_notifier_group_fd = lttng_get_unused_fd();
121 if (event_notifier_group_fd < 0) {
122 ret = event_notifier_group_fd;
123 goto fd_error;
124 }
125 event_notifier_group_file = anon_inode_getfile("[lttng_event_notifier_group]",
126 &lttng_event_notifier_group_fops,
127 event_notifier_group, O_RDWR);
128 if (IS_ERR(event_notifier_group_file)) {
129 ret = PTR_ERR(event_notifier_group_file);
130 goto file_error;
131 }
132
133 event_notifier_group->file = event_notifier_group_file;
134 fd_install(event_notifier_group_fd, event_notifier_group_file);
135 return event_notifier_group_fd;
136
137 file_error:
138 put_unused_fd(event_notifier_group_fd);
139 fd_error:
140 lttng_event_notifier_group_destroy(event_notifier_group);
141 return ret;
142 }
143
144 static
145 int lttng_abi_tracepoint_list(void)
146 {
147 struct file *tracepoint_list_file;
148 int file_fd, ret;
149
150 file_fd = lttng_get_unused_fd();
151 if (file_fd < 0) {
152 ret = file_fd;
153 goto fd_error;
154 }
155
156 tracepoint_list_file = anon_inode_getfile("[lttng_tracepoint_list]",
157 &lttng_tracepoint_list_fops,
158 NULL, O_RDWR);
159 if (IS_ERR(tracepoint_list_file)) {
160 ret = PTR_ERR(tracepoint_list_file);
161 goto file_error;
162 }
163 ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
164 if (ret < 0)
165 goto open_error;
166 fd_install(file_fd, tracepoint_list_file);
167 return file_fd;
168
169 open_error:
170 fput(tracepoint_list_file);
171 file_error:
172 put_unused_fd(file_fd);
173 fd_error:
174 return ret;
175 }
176
177 #ifndef CONFIG_HAVE_SYSCALL_TRACEPOINTS
178 static inline
179 int lttng_abi_syscall_list(void)
180 {
181 return -ENOSYS;
182 }
183 #else
184 static
185 int lttng_abi_syscall_list(void)
186 {
187 struct file *syscall_list_file;
188 int file_fd, ret;
189
190 file_fd = lttng_get_unused_fd();
191 if (file_fd < 0) {
192 ret = file_fd;
193 goto fd_error;
194 }
195
196 syscall_list_file = anon_inode_getfile("[lttng_syscall_list]",
197 &lttng_syscall_list_fops,
198 NULL, O_RDWR);
199 if (IS_ERR(syscall_list_file)) {
200 ret = PTR_ERR(syscall_list_file);
201 goto file_error;
202 }
203 ret = lttng_syscall_list_fops.open(NULL, syscall_list_file);
204 if (ret < 0)
205 goto open_error;
206 fd_install(file_fd, syscall_list_file);
207 return file_fd;
208
209 open_error:
210 fput(syscall_list_file);
211 file_error:
212 put_unused_fd(file_fd);
213 fd_error:
214 return ret;
215 }
216 #endif
217
218 static
219 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version *v)
220 {
221 v->major = LTTNG_MODULES_MAJOR_VERSION;
222 v->minor = LTTNG_MODULES_MINOR_VERSION;
223 v->patchlevel = LTTNG_MODULES_PATCHLEVEL_VERSION;
224 }
225
226 static
227 void lttng_abi_tracer_abi_version(struct lttng_kernel_tracer_abi_version *v)
228 {
229 v->major = LTTNG_MODULES_ABI_MAJOR_VERSION;
230 v->minor = LTTNG_MODULES_ABI_MINOR_VERSION;
231 }
232
233 static
234 long lttng_abi_add_context(struct file *file,
235 struct lttng_kernel_context *context_param,
236 struct lttng_ctx **ctx, struct lttng_session *session)
237 {
238
239 if (session->been_active)
240 return -EPERM;
241
242 switch (context_param->ctx) {
243 case LTTNG_KERNEL_CONTEXT_PID:
244 return lttng_add_pid_to_ctx(ctx);
245 case LTTNG_KERNEL_CONTEXT_PRIO:
246 return lttng_add_prio_to_ctx(ctx);
247 case LTTNG_KERNEL_CONTEXT_NICE:
248 return lttng_add_nice_to_ctx(ctx);
249 case LTTNG_KERNEL_CONTEXT_VPID:
250 return lttng_add_vpid_to_ctx(ctx);
251 case LTTNG_KERNEL_CONTEXT_TID:
252 return lttng_add_tid_to_ctx(ctx);
253 case LTTNG_KERNEL_CONTEXT_VTID:
254 return lttng_add_vtid_to_ctx(ctx);
255 case LTTNG_KERNEL_CONTEXT_PPID:
256 return lttng_add_ppid_to_ctx(ctx);
257 case LTTNG_KERNEL_CONTEXT_VPPID:
258 return lttng_add_vppid_to_ctx(ctx);
259 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
260 context_param->u.perf_counter.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
261 return lttng_add_perf_counter_to_ctx(context_param->u.perf_counter.type,
262 context_param->u.perf_counter.config,
263 context_param->u.perf_counter.name,
264 ctx);
265 case LTTNG_KERNEL_CONTEXT_PROCNAME:
266 return lttng_add_procname_to_ctx(ctx);
267 case LTTNG_KERNEL_CONTEXT_HOSTNAME:
268 return lttng_add_hostname_to_ctx(ctx);
269 case LTTNG_KERNEL_CONTEXT_CPU_ID:
270 return lttng_add_cpu_id_to_ctx(ctx);
271 case LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE:
272 return lttng_add_interruptible_to_ctx(ctx);
273 case LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE:
274 return lttng_add_need_reschedule_to_ctx(ctx);
275 case LTTNG_KERNEL_CONTEXT_PREEMPTIBLE:
276 return lttng_add_preemptible_to_ctx(ctx);
277 case LTTNG_KERNEL_CONTEXT_MIGRATABLE:
278 return lttng_add_migratable_to_ctx(ctx);
279 case LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL:
280 case LTTNG_KERNEL_CONTEXT_CALLSTACK_USER:
281 return lttng_add_callstack_to_ctx(ctx, context_param->ctx);
282 case LTTNG_KERNEL_CONTEXT_CGROUP_NS:
283 return lttng_add_cgroup_ns_to_ctx(ctx);
284 case LTTNG_KERNEL_CONTEXT_IPC_NS:
285 return lttng_add_ipc_ns_to_ctx(ctx);
286 case LTTNG_KERNEL_CONTEXT_MNT_NS:
287 return lttng_add_mnt_ns_to_ctx(ctx);
288 case LTTNG_KERNEL_CONTEXT_NET_NS:
289 return lttng_add_net_ns_to_ctx(ctx);
290 case LTTNG_KERNEL_CONTEXT_PID_NS:
291 return lttng_add_pid_ns_to_ctx(ctx);
292 case LTTNG_KERNEL_CONTEXT_USER_NS:
293 return lttng_add_user_ns_to_ctx(ctx);
294 case LTTNG_KERNEL_CONTEXT_UTS_NS:
295 return lttng_add_uts_ns_to_ctx(ctx);
296 case LTTNG_KERNEL_CONTEXT_UID:
297 return lttng_add_uid_to_ctx(ctx);
298 case LTTNG_KERNEL_CONTEXT_EUID:
299 return lttng_add_euid_to_ctx(ctx);
300 case LTTNG_KERNEL_CONTEXT_SUID:
301 return lttng_add_suid_to_ctx(ctx);
302 case LTTNG_KERNEL_CONTEXT_GID:
303 return lttng_add_gid_to_ctx(ctx);
304 case LTTNG_KERNEL_CONTEXT_EGID:
305 return lttng_add_egid_to_ctx(ctx);
306 case LTTNG_KERNEL_CONTEXT_SGID:
307 return lttng_add_sgid_to_ctx(ctx);
308 case LTTNG_KERNEL_CONTEXT_VUID:
309 return lttng_add_vuid_to_ctx(ctx);
310 case LTTNG_KERNEL_CONTEXT_VEUID:
311 return lttng_add_veuid_to_ctx(ctx);
312 case LTTNG_KERNEL_CONTEXT_VSUID:
313 return lttng_add_vsuid_to_ctx(ctx);
314 case LTTNG_KERNEL_CONTEXT_VGID:
315 return lttng_add_vgid_to_ctx(ctx);
316 case LTTNG_KERNEL_CONTEXT_VEGID:
317 return lttng_add_vegid_to_ctx(ctx);
318 case LTTNG_KERNEL_CONTEXT_VSGID:
319 return lttng_add_vsgid_to_ctx(ctx);
320 case LTTNG_KERNEL_CONTEXT_TIME_NS:
321 return lttng_add_time_ns_to_ctx(ctx);
322 default:
323 return -EINVAL;
324 }
325 }
326
327 /**
328 * lttng_ioctl - lttng syscall through ioctl
329 *
330 * @file: the file
331 * @cmd: the command
332 * @arg: command arg
333 *
334 * This ioctl implements lttng commands:
335 * LTTNG_KERNEL_SESSION
336 * Returns a LTTng trace session file descriptor
337 * LTTNG_KERNEL_TRACER_VERSION
338 * Returns the LTTng kernel tracer version
339 * LTTNG_KERNEL_TRACEPOINT_LIST
340 * Returns a file descriptor listing available tracepoints
341 * LTTNG_KERNEL_WAIT_QUIESCENT
342 * Returns after all previously running probes have completed
343 * LTTNG_KERNEL_TRACER_ABI_VERSION
344 * Returns the LTTng kernel tracer ABI version
345 * LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE
346 * Returns a LTTng event notifier group file descriptor
347 *
348 * The returned session will be deleted when its file descriptor is closed.
349 */
350 static
351 long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
352 {
353 switch (cmd) {
354 case LTTNG_KERNEL_OLD_SESSION:
355 case LTTNG_KERNEL_SESSION:
356 return lttng_abi_create_session();
357 case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE:
358 return lttng_abi_create_event_notifier_group();
359 case LTTNG_KERNEL_OLD_TRACER_VERSION:
360 {
361 struct lttng_kernel_tracer_version v;
362 struct lttng_kernel_old_tracer_version oldv;
363 struct lttng_kernel_old_tracer_version *uversion =
364 (struct lttng_kernel_old_tracer_version __user *) arg;
365
366 lttng_abi_tracer_version(&v);
367 oldv.major = v.major;
368 oldv.minor = v.minor;
369 oldv.patchlevel = v.patchlevel;
370
371 if (copy_to_user(uversion, &oldv, sizeof(oldv)))
372 return -EFAULT;
373 return 0;
374 }
375 case LTTNG_KERNEL_TRACER_VERSION:
376 {
377 struct lttng_kernel_tracer_version version;
378 struct lttng_kernel_tracer_version *uversion =
379 (struct lttng_kernel_tracer_version __user *) arg;
380
381 lttng_abi_tracer_version(&version);
382
383 if (copy_to_user(uversion, &version, sizeof(version)))
384 return -EFAULT;
385 return 0;
386 }
387 case LTTNG_KERNEL_TRACER_ABI_VERSION:
388 {
389 struct lttng_kernel_tracer_abi_version version;
390 struct lttng_kernel_tracer_abi_version *uversion =
391 (struct lttng_kernel_tracer_abi_version __user *) arg;
392
393 lttng_abi_tracer_abi_version(&version);
394
395 if (copy_to_user(uversion, &version, sizeof(version)))
396 return -EFAULT;
397 return 0;
398 }
399 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST:
400 case LTTNG_KERNEL_TRACEPOINT_LIST:
401 return lttng_abi_tracepoint_list();
402 case LTTNG_KERNEL_SYSCALL_LIST:
403 return lttng_abi_syscall_list();
404 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT:
405 case LTTNG_KERNEL_WAIT_QUIESCENT:
406 synchronize_trace();
407 return 0;
408 case LTTNG_KERNEL_OLD_CALIBRATE:
409 {
410 struct lttng_kernel_old_calibrate __user *ucalibrate =
411 (struct lttng_kernel_old_calibrate __user *) arg;
412 struct lttng_kernel_old_calibrate old_calibrate;
413 struct lttng_kernel_calibrate calibrate;
414 int ret;
415
416 if (copy_from_user(&old_calibrate, ucalibrate, sizeof(old_calibrate)))
417 return -EFAULT;
418 calibrate.type = old_calibrate.type;
419 ret = lttng_calibrate(&calibrate);
420 if (copy_to_user(ucalibrate, &old_calibrate, sizeof(old_calibrate)))
421 return -EFAULT;
422 return ret;
423 }
424 case LTTNG_KERNEL_CALIBRATE:
425 {
426 struct lttng_kernel_calibrate __user *ucalibrate =
427 (struct lttng_kernel_calibrate __user *) arg;
428 struct lttng_kernel_calibrate calibrate;
429 int ret;
430
431 if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate)))
432 return -EFAULT;
433 ret = lttng_calibrate(&calibrate);
434 if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate)))
435 return -EFAULT;
436 return ret;
437 }
438 default:
439 return -ENOIOCTLCMD;
440 }
441 }
442
443 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
444 static const struct proc_ops lttng_proc_ops = {
445 .proc_ioctl = lttng_ioctl,
446 #ifdef CONFIG_COMPAT
447 .proc_compat_ioctl = lttng_ioctl,
448 #endif /* CONFIG_COMPAT */
449 };
450 #else
451 static const struct file_operations lttng_proc_ops = {
452 .owner = THIS_MODULE,
453 .unlocked_ioctl = lttng_ioctl,
454 #ifdef CONFIG_COMPAT
455 .compat_ioctl = lttng_ioctl,
456 #endif /* CONFIG_COMPAT */
457 };
458 #endif
459
460 static
461 int lttng_abi_create_channel(struct file *session_file,
462 struct lttng_kernel_channel *chan_param,
463 enum channel_type channel_type)
464 {
465 struct lttng_session *session = session_file->private_data;
466 const struct file_operations *fops = NULL;
467 const char *transport_name;
468 struct lttng_channel *chan;
469 struct file *chan_file;
470 int chan_fd;
471 int ret = 0;
472
473 chan_fd = lttng_get_unused_fd();
474 if (chan_fd < 0) {
475 ret = chan_fd;
476 goto fd_error;
477 }
478 switch (channel_type) {
479 case PER_CPU_CHANNEL:
480 fops = &lttng_channel_fops;
481 break;
482 case METADATA_CHANNEL:
483 fops = &lttng_metadata_fops;
484 break;
485 }
486
487 chan_file = anon_inode_getfile("[lttng_channel]",
488 fops,
489 NULL, O_RDWR);
490 if (IS_ERR(chan_file)) {
491 ret = PTR_ERR(chan_file);
492 goto file_error;
493 }
494 switch (channel_type) {
495 case PER_CPU_CHANNEL:
496 if (chan_param->output == LTTNG_KERNEL_SPLICE) {
497 transport_name = chan_param->overwrite ?
498 "relay-overwrite" : "relay-discard";
499 } else if (chan_param->output == LTTNG_KERNEL_MMAP) {
500 transport_name = chan_param->overwrite ?
501 "relay-overwrite-mmap" : "relay-discard-mmap";
502 } else {
503 return -EINVAL;
504 }
505 break;
506 case METADATA_CHANNEL:
507 if (chan_param->output == LTTNG_KERNEL_SPLICE)
508 transport_name = "relay-metadata";
509 else if (chan_param->output == LTTNG_KERNEL_MMAP)
510 transport_name = "relay-metadata-mmap";
511 else
512 return -EINVAL;
513 break;
514 default:
515 transport_name = "<unknown>";
516 break;
517 }
518 if (!atomic_long_add_unless(&session_file->f_count, 1, LONG_MAX)) {
519 ret = -EOVERFLOW;
520 goto refcount_error;
521 }
522 /*
523 * We tolerate no failure path after channel creation. It will stay
524 * invariant for the rest of the session.
525 */
526 chan = lttng_channel_create(session, transport_name, NULL,
527 chan_param->subbuf_size,
528 chan_param->num_subbuf,
529 chan_param->switch_timer_interval,
530 chan_param->read_timer_interval,
531 channel_type);
532 if (!chan) {
533 ret = -EINVAL;
534 goto chan_error;
535 }
536 chan->file = chan_file;
537 chan_file->private_data = chan;
538 fd_install(chan_fd, chan_file);
539
540 return chan_fd;
541
542 chan_error:
543 atomic_long_dec(&session_file->f_count);
544 refcount_error:
545 fput(chan_file);
546 file_error:
547 put_unused_fd(chan_fd);
548 fd_error:
549 return ret;
550 }
551
552 static
553 int lttng_abi_session_set_name(struct lttng_session *session,
554 struct lttng_kernel_session_name *name)
555 {
556 size_t len;
557
558 len = strnlen(name->name, LTTNG_KERNEL_SESSION_NAME_LEN);
559
560 if (len == LTTNG_KERNEL_SESSION_NAME_LEN) {
561 /* Name is too long/malformed */
562 return -EINVAL;
563 }
564
565 strcpy(session->name, name->name);
566 return 0;
567 }
568
569 static
570 int lttng_abi_session_set_creation_time(struct lttng_session *session,
571 struct lttng_kernel_session_creation_time *time)
572 {
573 size_t len;
574
575 len = strnlen(time->iso8601, LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN);
576
577 if (len == LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN) {
578 /* Time is too long/malformed */
579 return -EINVAL;
580 }
581
582 strcpy(session->creation_time, time->iso8601);
583 return 0;
584 }
585
586 static
587 enum tracker_type get_tracker_type(struct lttng_kernel_tracker_args *tracker)
588 {
589 switch (tracker->type) {
590 case LTTNG_KERNEL_TRACKER_PID:
591 return TRACKER_PID;
592 case LTTNG_KERNEL_TRACKER_VPID:
593 return TRACKER_VPID;
594 case LTTNG_KERNEL_TRACKER_UID:
595 return TRACKER_UID;
596 case LTTNG_KERNEL_TRACKER_VUID:
597 return TRACKER_VUID;
598 case LTTNG_KERNEL_TRACKER_GID:
599 return TRACKER_GID;
600 case LTTNG_KERNEL_TRACKER_VGID:
601 return TRACKER_VGID;
602 default:
603 return TRACKER_UNKNOWN;
604 }
605 }
606
607 /**
608 * lttng_session_ioctl - lttng session fd ioctl
609 *
610 * @file: the file
611 * @cmd: the command
612 * @arg: command arg
613 *
614 * This ioctl implements lttng commands:
615 * LTTNG_KERNEL_CHANNEL
616 * Returns a LTTng channel file descriptor
617 * LTTNG_KERNEL_ENABLE
618 * Enables tracing for a session (weak enable)
619 * LTTNG_KERNEL_DISABLE
620 * Disables tracing for a session (strong disable)
621 * LTTNG_KERNEL_METADATA
622 * Returns a LTTng metadata file descriptor
623 * LTTNG_KERNEL_SESSION_TRACK_PID
624 * Add PID to session PID tracker
625 * LTTNG_KERNEL_SESSION_UNTRACK_PID
626 * Remove PID from session PID tracker
627 * LTTNG_KERNEL_SESSION_TRACK_ID
628 * Add ID to tracker
629 * LTTNG_KERNEL_SESSION_UNTRACK_ID
630 * Remove ID from tracker
631 *
632 * The returned channel will be deleted when its file descriptor is closed.
633 */
634 static
635 long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
636 {
637 struct lttng_session *session = file->private_data;
638 struct lttng_kernel_channel chan_param;
639 struct lttng_kernel_old_channel old_chan_param;
640
641 switch (cmd) {
642 case LTTNG_KERNEL_OLD_CHANNEL:
643 {
644 if (copy_from_user(&old_chan_param,
645 (struct lttng_kernel_old_channel __user *) arg,
646 sizeof(struct lttng_kernel_old_channel)))
647 return -EFAULT;
648 chan_param.overwrite = old_chan_param.overwrite;
649 chan_param.subbuf_size = old_chan_param.subbuf_size;
650 chan_param.num_subbuf = old_chan_param.num_subbuf;
651 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
652 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
653 chan_param.output = old_chan_param.output;
654
655 return lttng_abi_create_channel(file, &chan_param,
656 PER_CPU_CHANNEL);
657 }
658 case LTTNG_KERNEL_CHANNEL:
659 {
660 if (copy_from_user(&chan_param,
661 (struct lttng_kernel_channel __user *) arg,
662 sizeof(struct lttng_kernel_channel)))
663 return -EFAULT;
664 return lttng_abi_create_channel(file, &chan_param,
665 PER_CPU_CHANNEL);
666 }
667 case LTTNG_KERNEL_OLD_SESSION_START:
668 case LTTNG_KERNEL_OLD_ENABLE:
669 case LTTNG_KERNEL_SESSION_START:
670 case LTTNG_KERNEL_ENABLE:
671 return lttng_session_enable(session);
672 case LTTNG_KERNEL_OLD_SESSION_STOP:
673 case LTTNG_KERNEL_OLD_DISABLE:
674 case LTTNG_KERNEL_SESSION_STOP:
675 case LTTNG_KERNEL_DISABLE:
676 return lttng_session_disable(session);
677 case LTTNG_KERNEL_OLD_METADATA:
678 {
679 if (copy_from_user(&old_chan_param,
680 (struct lttng_kernel_old_channel __user *) arg,
681 sizeof(struct lttng_kernel_old_channel)))
682 return -EFAULT;
683 chan_param.overwrite = old_chan_param.overwrite;
684 chan_param.subbuf_size = old_chan_param.subbuf_size;
685 chan_param.num_subbuf = old_chan_param.num_subbuf;
686 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
687 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
688 chan_param.output = old_chan_param.output;
689
690 return lttng_abi_create_channel(file, &chan_param,
691 METADATA_CHANNEL);
692 }
693 case LTTNG_KERNEL_METADATA:
694 {
695 if (copy_from_user(&chan_param,
696 (struct lttng_kernel_channel __user *) arg,
697 sizeof(struct lttng_kernel_channel)))
698 return -EFAULT;
699 return lttng_abi_create_channel(file, &chan_param,
700 METADATA_CHANNEL);
701 }
702 case LTTNG_KERNEL_SESSION_TRACK_PID:
703 return lttng_session_track_id(session, TRACKER_PID, (int) arg);
704 case LTTNG_KERNEL_SESSION_UNTRACK_PID:
705 return lttng_session_untrack_id(session, TRACKER_PID, (int) arg);
706 case LTTNG_KERNEL_SESSION_TRACK_ID:
707 {
708 struct lttng_kernel_tracker_args tracker;
709 enum tracker_type tracker_type;
710
711 if (copy_from_user(&tracker,
712 (struct lttng_kernel_tracker_args __user *) arg,
713 sizeof(struct lttng_kernel_tracker_args)))
714 return -EFAULT;
715 tracker_type = get_tracker_type(&tracker);
716 if (tracker_type == TRACKER_UNKNOWN)
717 return -EINVAL;
718 return lttng_session_track_id(session, tracker_type, tracker.id);
719 }
720 case LTTNG_KERNEL_SESSION_UNTRACK_ID:
721 {
722 struct lttng_kernel_tracker_args tracker;
723 enum tracker_type tracker_type;
724
725 if (copy_from_user(&tracker,
726 (struct lttng_kernel_tracker_args __user *) arg,
727 sizeof(struct lttng_kernel_tracker_args)))
728 return -EFAULT;
729 tracker_type = get_tracker_type(&tracker);
730 if (tracker_type == TRACKER_UNKNOWN)
731 return -EINVAL;
732 return lttng_session_untrack_id(session, tracker_type,
733 tracker.id);
734 }
735 case LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS:
736 return lttng_session_list_tracker_ids(session, TRACKER_PID);
737 case LTTNG_KERNEL_SESSION_LIST_TRACKER_IDS:
738 {
739 struct lttng_kernel_tracker_args tracker;
740 enum tracker_type tracker_type;
741
742 if (copy_from_user(&tracker,
743 (struct lttng_kernel_tracker_args __user *) arg,
744 sizeof(struct lttng_kernel_tracker_args)))
745 return -EFAULT;
746 tracker_type = get_tracker_type(&tracker);
747 if (tracker_type == TRACKER_UNKNOWN)
748 return -EINVAL;
749 return lttng_session_list_tracker_ids(session, tracker_type);
750 }
751 case LTTNG_KERNEL_SESSION_METADATA_REGEN:
752 return lttng_session_metadata_regenerate(session);
753 case LTTNG_KERNEL_SESSION_STATEDUMP:
754 return lttng_session_statedump(session);
755 case LTTNG_KERNEL_SESSION_SET_NAME:
756 {
757 struct lttng_kernel_session_name name;
758
759 if (copy_from_user(&name,
760 (struct lttng_kernel_session_name __user *) arg,
761 sizeof(struct lttng_kernel_session_name)))
762 return -EFAULT;
763 return lttng_abi_session_set_name(session, &name);
764 }
765 case LTTNG_KERNEL_SESSION_SET_CREATION_TIME:
766 {
767 struct lttng_kernel_session_creation_time time;
768
769 if (copy_from_user(&time,
770 (struct lttng_kernel_session_creation_time __user *) arg,
771 sizeof(struct lttng_kernel_session_creation_time)))
772 return -EFAULT;
773 return lttng_abi_session_set_creation_time(session, &time);
774 }
775 default:
776 return -ENOIOCTLCMD;
777 }
778 }
779
780 /*
781 * Called when the last file reference is dropped.
782 *
783 * Big fat note: channels and events are invariant for the whole session after
784 * their creation. So this session destruction also destroys all channel and
785 * event structures specific to this session (they are not destroyed when their
786 * individual file is released).
787 */
788 static
789 int lttng_session_release(struct inode *inode, struct file *file)
790 {
791 struct lttng_session *session = file->private_data;
792
793 if (session)
794 lttng_session_destroy(session);
795 return 0;
796 }
797
798 static const struct file_operations lttng_session_fops = {
799 .owner = THIS_MODULE,
800 .release = lttng_session_release,
801 .unlocked_ioctl = lttng_session_ioctl,
802 #ifdef CONFIG_COMPAT
803 .compat_ioctl = lttng_session_ioctl,
804 #endif
805 };
806
807 /**
808 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
809 * @filp: the file
810 * @wait: poll table
811 *
812 * Handles the poll operations for the metadata channels.
813 */
814 static
815 unsigned int lttng_metadata_ring_buffer_poll(struct file *filp,
816 poll_table *wait)
817 {
818 struct lttng_metadata_stream *stream = filp->private_data;
819 struct lib_ring_buffer *buf = stream->priv;
820 int finalized;
821 unsigned int mask = 0;
822
823 if (filp->f_mode & FMODE_READ) {
824 poll_wait_set_exclusive(wait);
825 poll_wait(filp, &stream->read_wait, wait);
826
827 finalized = stream->finalized;
828
829 /*
830 * lib_ring_buffer_is_finalized() contains a smp_rmb()
831 * ordering finalized load before offsets loads.
832 */
833 WARN_ON(atomic_long_read(&buf->active_readers) != 1);
834
835 if (finalized)
836 mask |= POLLHUP;
837
838 mutex_lock(&stream->metadata_cache->lock);
839 if (stream->metadata_cache->metadata_written >
840 stream->metadata_out)
841 mask |= POLLIN;
842 mutex_unlock(&stream->metadata_cache->lock);
843 }
844
845 return mask;
846 }
847
848 static
849 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file *filp,
850 unsigned int cmd, unsigned long arg)
851 {
852 struct lttng_metadata_stream *stream = filp->private_data;
853
854 stream->metadata_out = stream->metadata_in;
855 }
856
857 /*
858 * Reset the counter of how much metadata has been consumed to 0. That way,
859 * the consumer receives the content of the metadata cache unchanged. This is
860 * different from the metadata_regenerate where the offset from epoch is
861 * resampled, here we want the exact same content as the last time the metadata
862 * was generated. This command is only possible if all the metadata written
863 * in the cache has been output to the metadata stream to avoid corrupting the
864 * metadata file.
865 *
866 * Return 0 on success, a negative value on error.
867 */
868 static
869 int lttng_metadata_cache_dump(struct lttng_metadata_stream *stream)
870 {
871 int ret;
872 struct lttng_metadata_cache *cache = stream->metadata_cache;
873
874 mutex_lock(&cache->lock);
875 if (stream->metadata_out != cache->metadata_written) {
876 ret = -EBUSY;
877 goto end;
878 }
879 stream->metadata_out = 0;
880 stream->metadata_in = 0;
881 wake_up_interruptible(&stream->read_wait);
882 ret = 0;
883
884 end:
885 mutex_unlock(&cache->lock);
886 return ret;
887 }
888
889 static
890 long lttng_metadata_ring_buffer_ioctl(struct file *filp,
891 unsigned int cmd, unsigned long arg)
892 {
893 int ret;
894 struct lttng_metadata_stream *stream = filp->private_data;
895 struct lib_ring_buffer *buf = stream->priv;
896 unsigned int rb_cmd;
897 bool coherent;
898
899 if (cmd == RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK)
900 rb_cmd = RING_BUFFER_GET_NEXT_SUBBUF;
901 else
902 rb_cmd = cmd;
903
904 switch (cmd) {
905 case RING_BUFFER_GET_NEXT_SUBBUF:
906 {
907 struct lttng_metadata_stream *stream = filp->private_data;
908 struct lib_ring_buffer *buf = stream->priv;
909 struct channel *chan = buf->backend.chan;
910
911 ret = lttng_metadata_output_channel(stream, chan, NULL);
912 if (ret > 0) {
913 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
914 ret = 0;
915 } else if (ret < 0)
916 goto err;
917 break;
918 }
919 case RING_BUFFER_GET_SUBBUF:
920 {
921 /*
922 * Random access is not allowed for metadata channel.
923 */
924 return -ENOSYS;
925 }
926 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
927 case RING_BUFFER_FLUSH:
928 {
929 struct lttng_metadata_stream *stream = filp->private_data;
930 struct lib_ring_buffer *buf = stream->priv;
931 struct channel *chan = buf->backend.chan;
932
933 /*
934 * Before doing the actual ring buffer flush, write up to one
935 * packet of metadata in the ring buffer.
936 */
937 ret = lttng_metadata_output_channel(stream, chan, NULL);
938 if (ret < 0)
939 goto err;
940 break;
941 }
942 case RING_BUFFER_GET_METADATA_VERSION:
943 {
944 struct lttng_metadata_stream *stream = filp->private_data;
945
946 return put_u64(stream->version, arg);
947 }
948 case RING_BUFFER_METADATA_CACHE_DUMP:
949 {
950 struct lttng_metadata_stream *stream = filp->private_data;
951
952 return lttng_metadata_cache_dump(stream);
953 }
954 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
955 {
956 struct lttng_metadata_stream *stream = filp->private_data;
957 struct lib_ring_buffer *buf = stream->priv;
958 struct channel *chan = buf->backend.chan;
959
960 ret = lttng_metadata_output_channel(stream, chan, &coherent);
961 if (ret > 0) {
962 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
963 ret = 0;
964 } else if (ret < 0) {
965 goto err;
966 }
967 break;
968 }
969 default:
970 break;
971 }
972 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
973
974 /* Performing lib ring buffer ioctl after our own. */
975 ret = lib_ring_buffer_ioctl(filp, rb_cmd, arg, buf);
976 if (ret < 0)
977 goto err;
978
979 switch (cmd) {
980 case RING_BUFFER_PUT_NEXT_SUBBUF:
981 {
982 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
983 cmd, arg);
984 break;
985 }
986 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
987 {
988 return put_u32(coherent, arg);
989 }
990 default:
991 break;
992 }
993 err:
994 return ret;
995 }
996
997 #ifdef CONFIG_COMPAT
998 static
999 long lttng_metadata_ring_buffer_compat_ioctl(struct file *filp,
1000 unsigned int cmd, unsigned long arg)
1001 {
1002 int ret;
1003 struct lttng_metadata_stream *stream = filp->private_data;
1004 struct lib_ring_buffer *buf = stream->priv;
1005 unsigned int rb_cmd;
1006 bool coherent;
1007
1008 if (cmd == RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK)
1009 rb_cmd = RING_BUFFER_GET_NEXT_SUBBUF;
1010 else
1011 rb_cmd = cmd;
1012
1013 switch (cmd) {
1014 case RING_BUFFER_GET_NEXT_SUBBUF:
1015 {
1016 struct lttng_metadata_stream *stream = filp->private_data;
1017 struct lib_ring_buffer *buf = stream->priv;
1018 struct channel *chan = buf->backend.chan;
1019
1020 ret = lttng_metadata_output_channel(stream, chan, NULL);
1021 if (ret > 0) {
1022 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1023 ret = 0;
1024 } else if (ret < 0)
1025 goto err;
1026 break;
1027 }
1028 case RING_BUFFER_GET_SUBBUF:
1029 {
1030 /*
1031 * Random access is not allowed for metadata channel.
1032 */
1033 return -ENOSYS;
1034 }
1035 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
1036 case RING_BUFFER_FLUSH:
1037 {
1038 struct lttng_metadata_stream *stream = filp->private_data;
1039 struct lib_ring_buffer *buf = stream->priv;
1040 struct channel *chan = buf->backend.chan;
1041
1042 /*
1043 * Before doing the actual ring buffer flush, write up to one
1044 * packet of metadata in the ring buffer.
1045 */
1046 ret = lttng_metadata_output_channel(stream, chan, NULL);
1047 if (ret < 0)
1048 goto err;
1049 break;
1050 }
1051 case RING_BUFFER_GET_METADATA_VERSION:
1052 {
1053 struct lttng_metadata_stream *stream = filp->private_data;
1054
1055 return put_u64(stream->version, arg);
1056 }
1057 case RING_BUFFER_METADATA_CACHE_DUMP:
1058 {
1059 struct lttng_metadata_stream *stream = filp->private_data;
1060
1061 return lttng_metadata_cache_dump(stream);
1062 }
1063 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1064 {
1065 struct lttng_metadata_stream *stream = filp->private_data;
1066 struct lib_ring_buffer *buf = stream->priv;
1067 struct channel *chan = buf->backend.chan;
1068
1069 ret = lttng_metadata_output_channel(stream, chan, &coherent);
1070 if (ret > 0) {
1071 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1072 ret = 0;
1073 } else if (ret < 0) {
1074 goto err;
1075 }
1076 break;
1077 }
1078 default:
1079 break;
1080 }
1081 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
1082
1083 /* Performing lib ring buffer ioctl after our own. */
1084 ret = lib_ring_buffer_compat_ioctl(filp, rb_cmd, arg, buf);
1085 if (ret < 0)
1086 goto err;
1087
1088 switch (cmd) {
1089 case RING_BUFFER_PUT_NEXT_SUBBUF:
1090 {
1091 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
1092 cmd, arg);
1093 break;
1094 }
1095 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1096 {
1097 return put_u32(coherent, arg);
1098 }
1099 default:
1100 break;
1101 }
1102 err:
1103 return ret;
1104 }
1105 #endif
1106
1107 /*
1108 * This is not used by anonymous file descriptors. This code is left
1109 * there if we ever want to implement an inode with open() operation.
1110 */
1111 static
1112 int lttng_metadata_ring_buffer_open(struct inode *inode, struct file *file)
1113 {
1114 struct lttng_metadata_stream *stream = inode->i_private;
1115 struct lib_ring_buffer *buf = stream->priv;
1116
1117 file->private_data = buf;
1118 /*
1119 * Since life-time of metadata cache differs from that of
1120 * session, we need to keep our own reference on the transport.
1121 */
1122 if (!try_module_get(stream->transport->owner)) {
1123 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
1124 return -EBUSY;
1125 }
1126 return lib_ring_buffer_open(inode, file, buf);
1127 }
1128
1129 static
1130 int lttng_metadata_ring_buffer_release(struct inode *inode, struct file *file)
1131 {
1132 struct lttng_metadata_stream *stream = file->private_data;
1133 struct lib_ring_buffer *buf = stream->priv;
1134
1135 mutex_lock(&stream->metadata_cache->lock);
1136 list_del(&stream->list);
1137 mutex_unlock(&stream->metadata_cache->lock);
1138 kref_put(&stream->metadata_cache->refcount, metadata_cache_destroy);
1139 module_put(stream->transport->owner);
1140 kfree(stream);
1141 return lib_ring_buffer_release(inode, file, buf);
1142 }
1143
1144 static
1145 ssize_t lttng_metadata_ring_buffer_splice_read(struct file *in, loff_t *ppos,
1146 struct pipe_inode_info *pipe, size_t len,
1147 unsigned int flags)
1148 {
1149 struct lttng_metadata_stream *stream = in->private_data;
1150 struct lib_ring_buffer *buf = stream->priv;
1151
1152 return lib_ring_buffer_splice_read(in, ppos, pipe, len,
1153 flags, buf);
1154 }
1155
1156 static
1157 int lttng_metadata_ring_buffer_mmap(struct file *filp,
1158 struct vm_area_struct *vma)
1159 {
1160 struct lttng_metadata_stream *stream = filp->private_data;
1161 struct lib_ring_buffer *buf = stream->priv;
1162
1163 return lib_ring_buffer_mmap(filp, vma, buf);
1164 }
1165
1166 static
1167 const struct file_operations lttng_metadata_ring_buffer_file_operations = {
1168 .owner = THIS_MODULE,
1169 .open = lttng_metadata_ring_buffer_open,
1170 .release = lttng_metadata_ring_buffer_release,
1171 .poll = lttng_metadata_ring_buffer_poll,
1172 .splice_read = lttng_metadata_ring_buffer_splice_read,
1173 .mmap = lttng_metadata_ring_buffer_mmap,
1174 .unlocked_ioctl = lttng_metadata_ring_buffer_ioctl,
1175 .llseek = vfs_lib_ring_buffer_no_llseek,
1176 #ifdef CONFIG_COMPAT
1177 .compat_ioctl = lttng_metadata_ring_buffer_compat_ioctl,
1178 #endif
1179 };
1180
1181 static
1182 int lttng_abi_create_stream_fd(struct file *channel_file, void *stream_priv,
1183 const struct file_operations *fops, const char *name)
1184 {
1185 int stream_fd, ret;
1186 struct file *stream_file;
1187
1188 stream_fd = lttng_get_unused_fd();
1189 if (stream_fd < 0) {
1190 ret = stream_fd;
1191 goto fd_error;
1192 }
1193 stream_file = anon_inode_getfile(name, fops, stream_priv, O_RDWR);
1194 if (IS_ERR(stream_file)) {
1195 ret = PTR_ERR(stream_file);
1196 goto file_error;
1197 }
1198 /*
1199 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
1200 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
1201 * file descriptor, so we set FMODE_PREAD here.
1202 */
1203 stream_file->f_mode |= FMODE_PREAD;
1204 fd_install(stream_fd, stream_file);
1205 /*
1206 * The stream holds a reference to the channel within the generic ring
1207 * buffer library, so no need to hold a refcount on the channel and
1208 * session files here.
1209 */
1210 return stream_fd;
1211
1212 file_error:
1213 put_unused_fd(stream_fd);
1214 fd_error:
1215 return ret;
1216 }
1217
1218 static
1219 int lttng_abi_open_stream(struct file *channel_file)
1220 {
1221 struct lttng_channel *channel = channel_file->private_data;
1222 struct lib_ring_buffer *buf;
1223 int ret;
1224 void *stream_priv;
1225
1226 buf = channel->ops->buffer_read_open(channel->chan);
1227 if (!buf)
1228 return -ENOENT;
1229
1230 stream_priv = buf;
1231 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
1232 &lttng_stream_ring_buffer_file_operations,
1233 "[lttng_stream]");
1234 if (ret < 0)
1235 goto fd_error;
1236
1237 return ret;
1238
1239 fd_error:
1240 channel->ops->buffer_read_close(buf);
1241 return ret;
1242 }
1243
1244 static
1245 int lttng_abi_open_metadata_stream(struct file *channel_file)
1246 {
1247 struct lttng_channel *channel = channel_file->private_data;
1248 struct lttng_session *session = channel->session;
1249 struct lib_ring_buffer *buf;
1250 int ret;
1251 struct lttng_metadata_stream *metadata_stream;
1252 void *stream_priv;
1253
1254 buf = channel->ops->buffer_read_open(channel->chan);
1255 if (!buf)
1256 return -ENOENT;
1257
1258 metadata_stream = kzalloc(sizeof(struct lttng_metadata_stream),
1259 GFP_KERNEL);
1260 if (!metadata_stream) {
1261 ret = -ENOMEM;
1262 goto nomem;
1263 }
1264 metadata_stream->metadata_cache = session->metadata_cache;
1265 init_waitqueue_head(&metadata_stream->read_wait);
1266 metadata_stream->priv = buf;
1267 stream_priv = metadata_stream;
1268 metadata_stream->transport = channel->transport;
1269 /* Initial state is an empty metadata, considered as incoherent. */
1270 metadata_stream->coherent = false;
1271
1272 /*
1273 * Since life-time of metadata cache differs from that of
1274 * session, we need to keep our own reference on the transport.
1275 */
1276 if (!try_module_get(metadata_stream->transport->owner)) {
1277 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
1278 ret = -EINVAL;
1279 goto notransport;
1280 }
1281
1282 if (!lttng_kref_get(&session->metadata_cache->refcount)) {
1283 ret = -EOVERFLOW;
1284 goto kref_error;
1285 }
1286
1287 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
1288 &lttng_metadata_ring_buffer_file_operations,
1289 "[lttng_metadata_stream]");
1290 if (ret < 0)
1291 goto fd_error;
1292
1293 mutex_lock(&session->metadata_cache->lock);
1294 list_add(&metadata_stream->list,
1295 &session->metadata_cache->metadata_stream);
1296 mutex_unlock(&session->metadata_cache->lock);
1297 return ret;
1298
1299 fd_error:
1300 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
1301 kref_error:
1302 module_put(metadata_stream->transport->owner);
1303 notransport:
1304 kfree(metadata_stream);
1305 nomem:
1306 channel->ops->buffer_read_close(buf);
1307 return ret;
1308 }
1309
1310 static
1311 int lttng_abi_validate_event_param(struct lttng_kernel_event *event_param)
1312 {
1313 /* Limit ABI to implemented features. */
1314 switch (event_param->instrumentation) {
1315 case LTTNG_KERNEL_SYSCALL:
1316 switch (event_param->u.syscall.entryexit) {
1317 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
1318 break;
1319 default:
1320 return -EINVAL;
1321 }
1322 switch (event_param->u.syscall.abi) {
1323 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
1324 break;
1325 default:
1326 return -EINVAL;
1327 }
1328 switch (event_param->u.syscall.match) {
1329 case LTTNG_SYSCALL_MATCH_NAME:
1330 break;
1331 default:
1332 return -EINVAL;
1333 }
1334 break;
1335
1336 case LTTNG_KERNEL_TRACEPOINT: /* Fallthrough */
1337 case LTTNG_KERNEL_KPROBE: /* Fallthrough */
1338 case LTTNG_KERNEL_KRETPROBE: /* Fallthrough */
1339 case LTTNG_KERNEL_NOOP: /* Fallthrough */
1340 case LTTNG_KERNEL_UPROBE:
1341 break;
1342
1343 case LTTNG_KERNEL_FUNCTION: /* Fallthrough */
1344 default:
1345 return -EINVAL;
1346 }
1347 return 0;
1348 }
1349
1350 static
1351 int lttng_abi_create_event(struct file *channel_file,
1352 struct lttng_kernel_event *event_param)
1353 {
1354 struct lttng_channel *channel = channel_file->private_data;
1355 int event_fd, ret;
1356 struct file *event_file;
1357 void *priv;
1358
1359 event_param->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1360 switch (event_param->instrumentation) {
1361 case LTTNG_KERNEL_KRETPROBE:
1362 event_param->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1363 break;
1364 case LTTNG_KERNEL_KPROBE:
1365 event_param->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1366 break;
1367 case LTTNG_KERNEL_FUNCTION:
1368 WARN_ON_ONCE(1);
1369 /* Not implemented. */
1370 break;
1371 default:
1372 break;
1373 }
1374 event_fd = lttng_get_unused_fd();
1375 if (event_fd < 0) {
1376 ret = event_fd;
1377 goto fd_error;
1378 }
1379 event_file = anon_inode_getfile("[lttng_event]",
1380 &lttng_event_fops,
1381 NULL, O_RDWR);
1382 if (IS_ERR(event_file)) {
1383 ret = PTR_ERR(event_file);
1384 goto file_error;
1385 }
1386 /* The event holds a reference on the channel */
1387 if (!atomic_long_add_unless(&channel_file->f_count, 1, LONG_MAX)) {
1388 ret = -EOVERFLOW;
1389 goto refcount_error;
1390 }
1391 ret = lttng_abi_validate_event_param(event_param);
1392 if (ret)
1393 goto event_error;
1394 if (event_param->instrumentation == LTTNG_KERNEL_TRACEPOINT
1395 || event_param->instrumentation == LTTNG_KERNEL_SYSCALL) {
1396 struct lttng_event_enabler *event_enabler;
1397
1398 if (strutils_is_star_glob_pattern(event_param->name)) {
1399 /*
1400 * If the event name is a star globbing pattern,
1401 * we create the special star globbing enabler.
1402 */
1403 event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_STAR_GLOB,
1404 event_param, channel);
1405 } else {
1406 event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_NAME,
1407 event_param, channel);
1408 }
1409 priv = event_enabler;
1410 } else {
1411 struct lttng_event *event;
1412
1413 /*
1414 * We tolerate no failure path after event creation. It
1415 * will stay invariant for the rest of the session.
1416 */
1417 event = lttng_event_create(channel, event_param,
1418 NULL, NULL,
1419 event_param->instrumentation);
1420 WARN_ON_ONCE(!event);
1421 if (IS_ERR(event)) {
1422 ret = PTR_ERR(event);
1423 goto event_error;
1424 }
1425 priv = event;
1426 }
1427 event_file->private_data = priv;
1428 fd_install(event_fd, event_file);
1429 return event_fd;
1430
1431 event_error:
1432 atomic_long_dec(&channel_file->f_count);
1433 refcount_error:
1434 fput(event_file);
1435 file_error:
1436 put_unused_fd(event_fd);
1437 fd_error:
1438 return ret;
1439 }
1440
1441 static
1442 long lttng_event_notifier_group_ioctl(struct file *file, unsigned int cmd,
1443 unsigned long arg)
1444 {
1445 switch (cmd) {
1446 default:
1447 return -ENOIOCTLCMD;
1448 }
1449 return 0;
1450 }
1451
1452 static
1453 int lttng_event_notifier_group_release(struct inode *inode, struct file *file)
1454 {
1455 struct lttng_event_notifier_group *event_notifier_group =
1456 file->private_data;
1457
1458 if (event_notifier_group)
1459 lttng_event_notifier_group_destroy(event_notifier_group);
1460 return 0;
1461 }
1462
1463 static const struct file_operations lttng_event_notifier_group_fops = {
1464 .owner = THIS_MODULE,
1465 .release = lttng_event_notifier_group_release,
1466 .unlocked_ioctl = lttng_event_notifier_group_ioctl,
1467 #ifdef CONFIG_COMPAT
1468 .compat_ioctl = lttng_event_notifier_group_ioctl,
1469 #endif
1470 };
1471
1472 /**
1473 * lttng_channel_ioctl - lttng syscall through ioctl
1474 *
1475 * @file: the file
1476 * @cmd: the command
1477 * @arg: command arg
1478 *
1479 * This ioctl implements lttng commands:
1480 * LTTNG_KERNEL_STREAM
1481 * Returns an event stream file descriptor or failure.
1482 * (typically, one event stream records events from one CPU)
1483 * LTTNG_KERNEL_EVENT
1484 * Returns an event file descriptor or failure.
1485 * LTTNG_KERNEL_CONTEXT
1486 * Prepend a context field to each event in the channel
1487 * LTTNG_KERNEL_ENABLE
1488 * Enable recording for events in this channel (weak enable)
1489 * LTTNG_KERNEL_DISABLE
1490 * Disable recording for events in this channel (strong disable)
1491 *
1492 * Channel and event file descriptors also hold a reference on the session.
1493 */
1494 static
1495 long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1496 {
1497 struct lttng_channel *channel = file->private_data;
1498
1499 switch (cmd) {
1500 case LTTNG_KERNEL_OLD_STREAM:
1501 case LTTNG_KERNEL_STREAM:
1502 return lttng_abi_open_stream(file);
1503 case LTTNG_KERNEL_OLD_EVENT:
1504 {
1505 struct lttng_kernel_event *uevent_param;
1506 struct lttng_kernel_old_event *old_uevent_param;
1507 int ret;
1508
1509 uevent_param = kmalloc(sizeof(struct lttng_kernel_event),
1510 GFP_KERNEL);
1511 if (!uevent_param) {
1512 ret = -ENOMEM;
1513 goto old_event_end;
1514 }
1515 old_uevent_param = kmalloc(
1516 sizeof(struct lttng_kernel_old_event),
1517 GFP_KERNEL);
1518 if (!old_uevent_param) {
1519 ret = -ENOMEM;
1520 goto old_event_error_free_param;
1521 }
1522 if (copy_from_user(old_uevent_param,
1523 (struct lttng_kernel_old_event __user *) arg,
1524 sizeof(struct lttng_kernel_old_event))) {
1525 ret = -EFAULT;
1526 goto old_event_error_free_old_param;
1527 }
1528
1529 memcpy(uevent_param->name, old_uevent_param->name,
1530 sizeof(uevent_param->name));
1531 uevent_param->instrumentation =
1532 old_uevent_param->instrumentation;
1533
1534 switch (old_uevent_param->instrumentation) {
1535 case LTTNG_KERNEL_KPROBE:
1536 uevent_param->u.kprobe.addr =
1537 old_uevent_param->u.kprobe.addr;
1538 uevent_param->u.kprobe.offset =
1539 old_uevent_param->u.kprobe.offset;
1540 memcpy(uevent_param->u.kprobe.symbol_name,
1541 old_uevent_param->u.kprobe.symbol_name,
1542 sizeof(uevent_param->u.kprobe.symbol_name));
1543 break;
1544 case LTTNG_KERNEL_KRETPROBE:
1545 uevent_param->u.kretprobe.addr =
1546 old_uevent_param->u.kretprobe.addr;
1547 uevent_param->u.kretprobe.offset =
1548 old_uevent_param->u.kretprobe.offset;
1549 memcpy(uevent_param->u.kretprobe.symbol_name,
1550 old_uevent_param->u.kretprobe.symbol_name,
1551 sizeof(uevent_param->u.kretprobe.symbol_name));
1552 break;
1553 case LTTNG_KERNEL_FUNCTION:
1554 WARN_ON_ONCE(1);
1555 /* Not implemented. */
1556 break;
1557 default:
1558 break;
1559 }
1560 ret = lttng_abi_create_event(file, uevent_param);
1561
1562 old_event_error_free_old_param:
1563 kfree(old_uevent_param);
1564 old_event_error_free_param:
1565 kfree(uevent_param);
1566 old_event_end:
1567 return ret;
1568 }
1569 case LTTNG_KERNEL_EVENT:
1570 {
1571 struct lttng_kernel_event uevent_param;
1572
1573 if (copy_from_user(&uevent_param,
1574 (struct lttng_kernel_event __user *) arg,
1575 sizeof(uevent_param)))
1576 return -EFAULT;
1577 return lttng_abi_create_event(file, &uevent_param);
1578 }
1579 case LTTNG_KERNEL_OLD_CONTEXT:
1580 {
1581 struct lttng_kernel_context *ucontext_param;
1582 struct lttng_kernel_old_context *old_ucontext_param;
1583 int ret;
1584
1585 ucontext_param = kmalloc(sizeof(struct lttng_kernel_context),
1586 GFP_KERNEL);
1587 if (!ucontext_param) {
1588 ret = -ENOMEM;
1589 goto old_ctx_end;
1590 }
1591 old_ucontext_param = kmalloc(sizeof(struct lttng_kernel_old_context),
1592 GFP_KERNEL);
1593 if (!old_ucontext_param) {
1594 ret = -ENOMEM;
1595 goto old_ctx_error_free_param;
1596 }
1597
1598 if (copy_from_user(old_ucontext_param,
1599 (struct lttng_kernel_old_context __user *) arg,
1600 sizeof(struct lttng_kernel_old_context))) {
1601 ret = -EFAULT;
1602 goto old_ctx_error_free_old_param;
1603 }
1604 ucontext_param->ctx = old_ucontext_param->ctx;
1605 memcpy(ucontext_param->padding, old_ucontext_param->padding,
1606 sizeof(ucontext_param->padding));
1607 /* only type that uses the union */
1608 if (old_ucontext_param->ctx == LTTNG_KERNEL_CONTEXT_PERF_COUNTER) {
1609 ucontext_param->u.perf_counter.type =
1610 old_ucontext_param->u.perf_counter.type;
1611 ucontext_param->u.perf_counter.config =
1612 old_ucontext_param->u.perf_counter.config;
1613 memcpy(ucontext_param->u.perf_counter.name,
1614 old_ucontext_param->u.perf_counter.name,
1615 sizeof(ucontext_param->u.perf_counter.name));
1616 }
1617
1618 ret = lttng_abi_add_context(file,
1619 ucontext_param,
1620 &channel->ctx, channel->session);
1621
1622 old_ctx_error_free_old_param:
1623 kfree(old_ucontext_param);
1624 old_ctx_error_free_param:
1625 kfree(ucontext_param);
1626 old_ctx_end:
1627 return ret;
1628 }
1629 case LTTNG_KERNEL_CONTEXT:
1630 {
1631 struct lttng_kernel_context ucontext_param;
1632
1633 if (copy_from_user(&ucontext_param,
1634 (struct lttng_kernel_context __user *) arg,
1635 sizeof(ucontext_param)))
1636 return -EFAULT;
1637 return lttng_abi_add_context(file,
1638 &ucontext_param,
1639 &channel->ctx, channel->session);
1640 }
1641 case LTTNG_KERNEL_OLD_ENABLE:
1642 case LTTNG_KERNEL_ENABLE:
1643 return lttng_channel_enable(channel);
1644 case LTTNG_KERNEL_OLD_DISABLE:
1645 case LTTNG_KERNEL_DISABLE:
1646 return lttng_channel_disable(channel);
1647 case LTTNG_KERNEL_SYSCALL_MASK:
1648 return lttng_channel_syscall_mask(channel,
1649 (struct lttng_kernel_syscall_mask __user *) arg);
1650 default:
1651 return -ENOIOCTLCMD;
1652 }
1653 }
1654
1655 /**
1656 * lttng_metadata_ioctl - lttng syscall through ioctl
1657 *
1658 * @file: the file
1659 * @cmd: the command
1660 * @arg: command arg
1661 *
1662 * This ioctl implements lttng commands:
1663 * LTTNG_KERNEL_STREAM
1664 * Returns an event stream file descriptor or failure.
1665 *
1666 * Channel and event file descriptors also hold a reference on the session.
1667 */
1668 static
1669 long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1670 {
1671 switch (cmd) {
1672 case LTTNG_KERNEL_OLD_STREAM:
1673 case LTTNG_KERNEL_STREAM:
1674 return lttng_abi_open_metadata_stream(file);
1675 default:
1676 return -ENOIOCTLCMD;
1677 }
1678 }
1679
1680 /**
1681 * lttng_channel_poll - lttng stream addition/removal monitoring
1682 *
1683 * @file: the file
1684 * @wait: poll table
1685 */
1686 unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
1687 {
1688 struct lttng_channel *channel = file->private_data;
1689 unsigned int mask = 0;
1690
1691 if (file->f_mode & FMODE_READ) {
1692 poll_wait_set_exclusive(wait);
1693 poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
1694 wait);
1695
1696 if (channel->ops->is_disabled(channel->chan))
1697 return POLLERR;
1698 if (channel->ops->is_finalized(channel->chan))
1699 return POLLHUP;
1700 if (channel->ops->buffer_has_read_closed_stream(channel->chan))
1701 return POLLIN | POLLRDNORM;
1702 return 0;
1703 }
1704 return mask;
1705
1706 }
1707
1708 static
1709 int lttng_channel_release(struct inode *inode, struct file *file)
1710 {
1711 struct lttng_channel *channel = file->private_data;
1712
1713 if (channel)
1714 fput(channel->session->file);
1715 return 0;
1716 }
1717
1718 static
1719 int lttng_metadata_channel_release(struct inode *inode, struct file *file)
1720 {
1721 struct lttng_channel *channel = file->private_data;
1722
1723 if (channel) {
1724 fput(channel->session->file);
1725 lttng_metadata_channel_destroy(channel);
1726 }
1727
1728 return 0;
1729 }
1730
1731 static const struct file_operations lttng_channel_fops = {
1732 .owner = THIS_MODULE,
1733 .release = lttng_channel_release,
1734 .poll = lttng_channel_poll,
1735 .unlocked_ioctl = lttng_channel_ioctl,
1736 #ifdef CONFIG_COMPAT
1737 .compat_ioctl = lttng_channel_ioctl,
1738 #endif
1739 };
1740
1741 static const struct file_operations lttng_metadata_fops = {
1742 .owner = THIS_MODULE,
1743 .release = lttng_metadata_channel_release,
1744 .unlocked_ioctl = lttng_metadata_ioctl,
1745 #ifdef CONFIG_COMPAT
1746 .compat_ioctl = lttng_metadata_ioctl,
1747 #endif
1748 };
1749
1750 /**
1751 * lttng_event_ioctl - lttng syscall through ioctl
1752 *
1753 * @file: the file
1754 * @cmd: the command
1755 * @arg: command arg
1756 *
1757 * This ioctl implements lttng commands:
1758 * LTTNG_KERNEL_CONTEXT
1759 * Prepend a context field to each record of this event
1760 * LTTNG_KERNEL_ENABLE
1761 * Enable recording for this event (weak enable)
1762 * LTTNG_KERNEL_DISABLE
1763 * Disable recording for this event (strong disable)
1764 */
1765 static
1766 long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1767 {
1768 struct lttng_event *event;
1769 struct lttng_event_enabler *event_enabler;
1770 enum lttng_event_type *evtype = file->private_data;
1771
1772 switch (cmd) {
1773 case LTTNG_KERNEL_OLD_CONTEXT:
1774 {
1775 /* Not implemented */
1776 return -ENOSYS;
1777 }
1778 case LTTNG_KERNEL_CONTEXT:
1779 {
1780 /* Not implemented */
1781 return -ENOSYS;
1782 }
1783 case LTTNG_KERNEL_OLD_ENABLE:
1784 case LTTNG_KERNEL_ENABLE:
1785 switch (*evtype) {
1786 case LTTNG_TYPE_EVENT:
1787 event = file->private_data;
1788 return lttng_event_enable(event);
1789 case LTTNG_TYPE_ENABLER:
1790 event_enabler = file->private_data;
1791 return lttng_event_enabler_enable(event_enabler);
1792 default:
1793 WARN_ON_ONCE(1);
1794 return -ENOSYS;
1795 }
1796 case LTTNG_KERNEL_OLD_DISABLE:
1797 case LTTNG_KERNEL_DISABLE:
1798 switch (*evtype) {
1799 case LTTNG_TYPE_EVENT:
1800 event = file->private_data;
1801 return lttng_event_disable(event);
1802 case LTTNG_TYPE_ENABLER:
1803 event_enabler = file->private_data;
1804 return lttng_event_enabler_disable(event_enabler);
1805 default:
1806 WARN_ON_ONCE(1);
1807 return -ENOSYS;
1808 }
1809 case LTTNG_KERNEL_FILTER:
1810 switch (*evtype) {
1811 case LTTNG_TYPE_EVENT:
1812 return -EINVAL;
1813 case LTTNG_TYPE_ENABLER:
1814 {
1815 event_enabler = file->private_data;
1816 return lttng_event_enabler_attach_bytecode(event_enabler,
1817 (struct lttng_kernel_filter_bytecode __user *) arg);
1818 }
1819 default:
1820 WARN_ON_ONCE(1);
1821 return -ENOSYS;
1822 }
1823 case LTTNG_KERNEL_ADD_CALLSITE:
1824 switch (*evtype) {
1825 case LTTNG_TYPE_EVENT:
1826 event = file->private_data;
1827 return lttng_event_add_callsite(event,
1828 (struct lttng_kernel_event_callsite __user *) arg);
1829 case LTTNG_TYPE_ENABLER:
1830 return -EINVAL;
1831 default:
1832 WARN_ON_ONCE(1);
1833 return -ENOSYS;
1834 }
1835 default:
1836 return -ENOIOCTLCMD;
1837 }
1838 }
1839
1840 static
1841 int lttng_event_release(struct inode *inode, struct file *file)
1842 {
1843 struct lttng_event *event;
1844 struct lttng_event_enabler *event_enabler;
1845 enum lttng_event_type *evtype = file->private_data;
1846
1847 if (!evtype)
1848 return 0;
1849
1850 switch (*evtype) {
1851 case LTTNG_TYPE_EVENT:
1852 event = file->private_data;
1853 if (event)
1854 fput(event->chan->file);
1855 break;
1856 case LTTNG_TYPE_ENABLER:
1857 event_enabler = file->private_data;
1858 if (event_enabler)
1859 fput(event_enabler->chan->file);
1860 break;
1861 default:
1862 WARN_ON_ONCE(1);
1863 break;
1864 }
1865
1866 return 0;
1867 }
1868
1869 /* TODO: filter control ioctl */
1870 static const struct file_operations lttng_event_fops = {
1871 .owner = THIS_MODULE,
1872 .release = lttng_event_release,
1873 .unlocked_ioctl = lttng_event_ioctl,
1874 #ifdef CONFIG_COMPAT
1875 .compat_ioctl = lttng_event_ioctl,
1876 #endif
1877 };
1878
1879 static int put_u64(uint64_t val, unsigned long arg)
1880 {
1881 return put_user(val, (uint64_t __user *) arg);
1882 }
1883
1884 static int put_u32(uint32_t val, unsigned long arg)
1885 {
1886 return put_user(val, (uint32_t __user *) arg);
1887 }
1888
1889 static long lttng_stream_ring_buffer_ioctl(struct file *filp,
1890 unsigned int cmd, unsigned long arg)
1891 {
1892 struct lib_ring_buffer *buf = filp->private_data;
1893 struct channel *chan = buf->backend.chan;
1894 const struct lib_ring_buffer_config *config = &chan->backend.config;
1895 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
1896 int ret;
1897
1898 if (atomic_read(&chan->record_disabled))
1899 return -EIO;
1900
1901 switch (cmd) {
1902 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN:
1903 {
1904 uint64_t ts;
1905
1906 ret = ops->timestamp_begin(config, buf, &ts);
1907 if (ret < 0)
1908 goto error;
1909 return put_u64(ts, arg);
1910 }
1911 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END:
1912 {
1913 uint64_t ts;
1914
1915 ret = ops->timestamp_end(config, buf, &ts);
1916 if (ret < 0)
1917 goto error;
1918 return put_u64(ts, arg);
1919 }
1920 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED:
1921 {
1922 uint64_t ed;
1923
1924 ret = ops->events_discarded(config, buf, &ed);
1925 if (ret < 0)
1926 goto error;
1927 return put_u64(ed, arg);
1928 }
1929 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE:
1930 {
1931 uint64_t cs;
1932
1933 ret = ops->content_size(config, buf, &cs);
1934 if (ret < 0)
1935 goto error;
1936 return put_u64(cs, arg);
1937 }
1938 case LTTNG_RING_BUFFER_GET_PACKET_SIZE:
1939 {
1940 uint64_t ps;
1941
1942 ret = ops->packet_size(config, buf, &ps);
1943 if (ret < 0)
1944 goto error;
1945 return put_u64(ps, arg);
1946 }
1947 case LTTNG_RING_BUFFER_GET_STREAM_ID:
1948 {
1949 uint64_t si;
1950
1951 ret = ops->stream_id(config, buf, &si);
1952 if (ret < 0)
1953 goto error;
1954 return put_u64(si, arg);
1955 }
1956 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
1957 {
1958 uint64_t ts;
1959
1960 ret = ops->current_timestamp(config, buf, &ts);
1961 if (ret < 0)
1962 goto error;
1963 return put_u64(ts, arg);
1964 }
1965 case LTTNG_RING_BUFFER_GET_SEQ_NUM:
1966 {
1967 uint64_t seq;
1968
1969 ret = ops->sequence_number(config, buf, &seq);
1970 if (ret < 0)
1971 goto error;
1972 return put_u64(seq, arg);
1973 }
1974 case LTTNG_RING_BUFFER_INSTANCE_ID:
1975 {
1976 uint64_t id;
1977
1978 ret = ops->instance_id(config, buf, &id);
1979 if (ret < 0)
1980 goto error;
1981 return put_u64(id, arg);
1982 }
1983 default:
1984 return lib_ring_buffer_file_operations.unlocked_ioctl(filp,
1985 cmd, arg);
1986 }
1987
1988 error:
1989 return -ENOSYS;
1990 }
1991
1992 #ifdef CONFIG_COMPAT
1993 static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
1994 unsigned int cmd, unsigned long arg)
1995 {
1996 struct lib_ring_buffer *buf = filp->private_data;
1997 struct channel *chan = buf->backend.chan;
1998 const struct lib_ring_buffer_config *config = &chan->backend.config;
1999 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
2000 int ret;
2001
2002 if (atomic_read(&chan->record_disabled))
2003 return -EIO;
2004
2005 switch (cmd) {
2006 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN:
2007 {
2008 uint64_t ts;
2009
2010 ret = ops->timestamp_begin(config, buf, &ts);
2011 if (ret < 0)
2012 goto error;
2013 return put_u64(ts, arg);
2014 }
2015 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END:
2016 {
2017 uint64_t ts;
2018
2019 ret = ops->timestamp_end(config, buf, &ts);
2020 if (ret < 0)
2021 goto error;
2022 return put_u64(ts, arg);
2023 }
2024 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED:
2025 {
2026 uint64_t ed;
2027
2028 ret = ops->events_discarded(config, buf, &ed);
2029 if (ret < 0)
2030 goto error;
2031 return put_u64(ed, arg);
2032 }
2033 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE:
2034 {
2035 uint64_t cs;
2036
2037 ret = ops->content_size(config, buf, &cs);
2038 if (ret < 0)
2039 goto error;
2040 return put_u64(cs, arg);
2041 }
2042 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE:
2043 {
2044 uint64_t ps;
2045
2046 ret = ops->packet_size(config, buf, &ps);
2047 if (ret < 0)
2048 goto error;
2049 return put_u64(ps, arg);
2050 }
2051 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID:
2052 {
2053 uint64_t si;
2054
2055 ret = ops->stream_id(config, buf, &si);
2056 if (ret < 0)
2057 goto error;
2058 return put_u64(si, arg);
2059 }
2060 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
2061 {
2062 uint64_t ts;
2063
2064 ret = ops->current_timestamp(config, buf, &ts);
2065 if (ret < 0)
2066 goto error;
2067 return put_u64(ts, arg);
2068 }
2069 case LTTNG_RING_BUFFER_COMPAT_GET_SEQ_NUM:
2070 {
2071 uint64_t seq;
2072
2073 ret = ops->sequence_number(config, buf, &seq);
2074 if (ret < 0)
2075 goto error;
2076 return put_u64(seq, arg);
2077 }
2078 case LTTNG_RING_BUFFER_COMPAT_INSTANCE_ID:
2079 {
2080 uint64_t id;
2081
2082 ret = ops->instance_id(config, buf, &id);
2083 if (ret < 0)
2084 goto error;
2085 return put_u64(id, arg);
2086 }
2087 default:
2088 return lib_ring_buffer_file_operations.compat_ioctl(filp,
2089 cmd, arg);
2090 }
2091
2092 error:
2093 return -ENOSYS;
2094 }
2095 #endif /* CONFIG_COMPAT */
2096
2097 static void lttng_stream_override_ring_buffer_fops(void)
2098 {
2099 lttng_stream_ring_buffer_file_operations.owner = THIS_MODULE;
2100 lttng_stream_ring_buffer_file_operations.open =
2101 lib_ring_buffer_file_operations.open;
2102 lttng_stream_ring_buffer_file_operations.release =
2103 lib_ring_buffer_file_operations.release;
2104 lttng_stream_ring_buffer_file_operations.poll =
2105 lib_ring_buffer_file_operations.poll;
2106 lttng_stream_ring_buffer_file_operations.splice_read =
2107 lib_ring_buffer_file_operations.splice_read;
2108 lttng_stream_ring_buffer_file_operations.mmap =
2109 lib_ring_buffer_file_operations.mmap;
2110 lttng_stream_ring_buffer_file_operations.unlocked_ioctl =
2111 lttng_stream_ring_buffer_ioctl;
2112 lttng_stream_ring_buffer_file_operations.llseek =
2113 lib_ring_buffer_file_operations.llseek;
2114 #ifdef CONFIG_COMPAT
2115 lttng_stream_ring_buffer_file_operations.compat_ioctl =
2116 lttng_stream_ring_buffer_compat_ioctl;
2117 #endif
2118 }
2119
2120 int __init lttng_abi_init(void)
2121 {
2122 int ret = 0;
2123
2124 wrapper_vmalloc_sync_mappings();
2125 lttng_clock_ref();
2126
2127 ret = lttng_tp_mempool_init();
2128 if (ret) {
2129 goto error;
2130 }
2131
2132 lttng_proc_dentry = proc_create_data("lttng", S_IRUSR | S_IWUSR, NULL,
2133 &lttng_proc_ops, NULL);
2134
2135 if (!lttng_proc_dentry) {
2136 printk(KERN_ERR "LTTng: Error creating control file\n");
2137 ret = -ENOMEM;
2138 goto error;
2139 }
2140 lttng_stream_override_ring_buffer_fops();
2141 return 0;
2142
2143 error:
2144 lttng_tp_mempool_destroy();
2145 lttng_clock_unref();
2146 return ret;
2147 }
2148
2149 /* No __exit annotation because used by init error path too. */
2150 void lttng_abi_exit(void)
2151 {
2152 lttng_tp_mempool_destroy();
2153 lttng_clock_unref();
2154 if (lttng_proc_dentry)
2155 remove_proc_entry("lttng", NULL);
2156 }
LTTng 2.0/0.x modules
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