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Cleanup: lttng-abi.h coding style
[deliverable/lttng-modules.git] / lttng-abi.c
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1/*
2 * lttng-abi.c
3 *
4 * LTTng ABI
5 *
6 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; only
11 * version 2.1 of the License.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 *
23 * Mimic system calls for:
24 * - session creation, returns a file descriptor or failure.
25 * - channel creation, returns a file descriptor or failure.
26 * - Operates on a session file descriptor
27 * - Takes all channel options as parameters.
28 * - stream get, returns a file descriptor or failure.
29 * - Operates on a channel file descriptor.
30 * - stream notifier get, returns a file descriptor or failure.
31 * - Operates on a channel file descriptor.
32 * - event creation, returns a file descriptor or failure.
33 * - Operates on a channel file descriptor
34 * - Takes an event name as parameter
35 * - Takes an instrumentation source as parameter
36 * - e.g. tracepoints, dynamic_probes...
37 * - Takes instrumentation source specific arguments.
38 */
39
40#include <linux/module.h>
41#include <linux/proc_fs.h>
42#include <linux/anon_inodes.h>
43#include <linux/file.h>
44#include <linux/uaccess.h>
45#include <linux/slab.h>
46#include <linux/err.h>
47#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
48#include "wrapper/ringbuffer/vfs.h"
49#include "wrapper/ringbuffer/backend.h"
50#include "wrapper/ringbuffer/frontend.h"
51#include "wrapper/poll.h"
52#include "lttng-abi.h"
53#include "lttng-abi-old.h"
54#include "lttng-events.h"
55#include "lttng-tracer.h"
56#include "lib/ringbuffer/frontend_types.h"
57
58/*
59 * This is LTTng's own personal way to create a system call as an external
60 * module. We use ioctl() on /proc/lttng.
61 */
62
63static struct proc_dir_entry *lttng_proc_dentry;
64static const struct file_operations lttng_fops;
65static const struct file_operations lttng_session_fops;
66static const struct file_operations lttng_channel_fops;
67static const struct file_operations lttng_metadata_fops;
68static const struct file_operations lttng_event_fops;
69static struct file_operations lttng_stream_ring_buffer_file_operations;
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
76static
77int 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 = 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
102file_error:
103 put_unused_fd(session_fd);
104fd_error:
105 lttng_session_destroy(session);
106 return ret;
107}
108
109static
110int lttng_abi_tracepoint_list(void)
111{
112 struct file *tracepoint_list_file;
113 int file_fd, ret;
114
115 file_fd = get_unused_fd();
116 if (file_fd < 0) {
117 ret = file_fd;
118 goto fd_error;
119 }
120
121 tracepoint_list_file = anon_inode_getfile("[lttng_tracepoint_list]",
122 &lttng_tracepoint_list_fops,
123 NULL, O_RDWR);
124 if (IS_ERR(tracepoint_list_file)) {
125 ret = PTR_ERR(tracepoint_list_file);
126 goto file_error;
127 }
128 ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
129 if (ret < 0)
130 goto open_error;
131 fd_install(file_fd, tracepoint_list_file);
132 if (file_fd < 0) {
133 ret = file_fd;
134 goto fd_error;
135 }
136 return file_fd;
137
138open_error:
139 fput(tracepoint_list_file);
140file_error:
141 put_unused_fd(file_fd);
142fd_error:
143 return ret;
144}
145
146static
147int lttng_abi_syscall_list(void)
148{
149 struct file *syscall_list_file;
150 int file_fd, ret;
151
152 file_fd = get_unused_fd();
153 if (file_fd < 0) {
154 ret = file_fd;
155 goto fd_error;
156 }
157
158 syscall_list_file = anon_inode_getfile("[lttng_syscall_list]",
159 &lttng_syscall_list_fops,
160 NULL, O_RDWR);
161 if (IS_ERR(syscall_list_file)) {
162 ret = PTR_ERR(syscall_list_file);
163 goto file_error;
164 }
165 ret = lttng_syscall_list_fops.open(NULL, syscall_list_file);
166 if (ret < 0)
167 goto open_error;
168 fd_install(file_fd, syscall_list_file);
169 if (file_fd < 0) {
170 ret = file_fd;
171 goto fd_error;
172 }
173 return file_fd;
174
175open_error:
176 fput(syscall_list_file);
177file_error:
178 put_unused_fd(file_fd);
179fd_error:
180 return ret;
181}
182
183static
184void lttng_abi_tracer_version(struct lttng_kernel_tracer_version *v)
185{
186 v->major = LTTNG_MODULES_MAJOR_VERSION;
187 v->minor = LTTNG_MODULES_MINOR_VERSION;
188 v->patchlevel = LTTNG_MODULES_PATCHLEVEL_VERSION;
189}
190
191static
192long lttng_abi_add_context(struct file *file,
193 struct lttng_kernel_context *context_param,
194 struct lttng_ctx **ctx, struct lttng_session *session)
195{
196
197 if (session->been_active)
198 return -EPERM;
199
200 switch (context_param->ctx) {
201 case LTTNG_KERNEL_CONTEXT_PID:
202 return lttng_add_pid_to_ctx(ctx);
203 case LTTNG_KERNEL_CONTEXT_PRIO:
204 return lttng_add_prio_to_ctx(ctx);
205 case LTTNG_KERNEL_CONTEXT_NICE:
206 return lttng_add_nice_to_ctx(ctx);
207 case LTTNG_KERNEL_CONTEXT_VPID:
208 return lttng_add_vpid_to_ctx(ctx);
209 case LTTNG_KERNEL_CONTEXT_TID:
210 return lttng_add_tid_to_ctx(ctx);
211 case LTTNG_KERNEL_CONTEXT_VTID:
212 return lttng_add_vtid_to_ctx(ctx);
213 case LTTNG_KERNEL_CONTEXT_PPID:
214 return lttng_add_ppid_to_ctx(ctx);
215 case LTTNG_KERNEL_CONTEXT_VPPID:
216 return lttng_add_vppid_to_ctx(ctx);
217 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
218 context_param->u.perf_counter.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
219 return lttng_add_perf_counter_to_ctx(context_param->u.perf_counter.type,
220 context_param->u.perf_counter.config,
221 context_param->u.perf_counter.name,
222 ctx);
223 case LTTNG_KERNEL_CONTEXT_PROCNAME:
224 return lttng_add_procname_to_ctx(ctx);
225 case LTTNG_KERNEL_CONTEXT_HOSTNAME:
226 return lttng_add_hostname_to_ctx(ctx);
227 default:
228 return -EINVAL;
229 }
230}
231
232/**
233 * lttng_ioctl - lttng syscall through ioctl
234 *
235 * @file: the file
236 * @cmd: the command
237 * @arg: command arg
238 *
239 * This ioctl implements lttng commands:
240 * LTTNG_KERNEL_SESSION
241 * Returns a LTTng trace session file descriptor
242 * LTTNG_KERNEL_TRACER_VERSION
243 * Returns the LTTng kernel tracer version
244 * LTTNG_KERNEL_TRACEPOINT_LIST
245 * Returns a file descriptor listing available tracepoints
246 * LTTNG_KERNEL_WAIT_QUIESCENT
247 * Returns after all previously running probes have completed
248 *
249 * The returned session will be deleted when its file descriptor is closed.
250 */
251static
252long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
253{
254 switch (cmd) {
255 case LTTNG_KERNEL_OLD_SESSION:
256 case LTTNG_KERNEL_SESSION:
257 return lttng_abi_create_session();
258 case LTTNG_KERNEL_OLD_TRACER_VERSION:
259 {
260 struct lttng_kernel_tracer_version v;
261 struct lttng_kernel_old_tracer_version oldv;
262 struct lttng_kernel_old_tracer_version *uversion =
263 (struct lttng_kernel_old_tracer_version __user *) arg;
264
265 lttng_abi_tracer_version(&v);
266 oldv.major = v.major;
267 oldv.minor = v.minor;
268 oldv.patchlevel = v.patchlevel;
269
270 if (copy_to_user(uversion, &oldv, sizeof(oldv)))
271 return -EFAULT;
272 return 0;
273 }
274 case LTTNG_KERNEL_TRACER_VERSION:
275 {
276 struct lttng_kernel_tracer_version version;
277 struct lttng_kernel_tracer_version *uversion =
278 (struct lttng_kernel_tracer_version __user *) arg;
279
280 lttng_abi_tracer_version(&version);
281
282 if (copy_to_user(uversion, &version, sizeof(version)))
283 return -EFAULT;
284 return 0;
285 }
286 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST:
287 case LTTNG_KERNEL_TRACEPOINT_LIST:
288 return lttng_abi_tracepoint_list();
289 case LTTNG_KERNEL_SYSCALL_LIST:
290 return lttng_abi_syscall_list();
291 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT:
292 case LTTNG_KERNEL_WAIT_QUIESCENT:
293 synchronize_trace();
294 return 0;
295 case LTTNG_KERNEL_OLD_CALIBRATE:
296 {
297 struct lttng_kernel_old_calibrate __user *ucalibrate =
298 (struct lttng_kernel_old_calibrate __user *) arg;
299 struct lttng_kernel_old_calibrate old_calibrate;
300 struct lttng_kernel_calibrate calibrate;
301 int ret;
302
303 if (copy_from_user(&old_calibrate, ucalibrate, sizeof(old_calibrate)))
304 return -EFAULT;
305 calibrate.type = old_calibrate.type;
306 ret = lttng_calibrate(&calibrate);
307 if (copy_to_user(ucalibrate, &old_calibrate, sizeof(old_calibrate)))
308 return -EFAULT;
309 return ret;
310 }
311 case LTTNG_KERNEL_CALIBRATE:
312 {
313 struct lttng_kernel_calibrate __user *ucalibrate =
314 (struct lttng_kernel_calibrate __user *) arg;
315 struct lttng_kernel_calibrate calibrate;
316 int ret;
317
318 if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate)))
319 return -EFAULT;
320 ret = lttng_calibrate(&calibrate);
321 if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate)))
322 return -EFAULT;
323 return ret;
324 }
325 default:
326 return -ENOIOCTLCMD;
327 }
328}
329
330static const struct file_operations lttng_fops = {
331 .owner = THIS_MODULE,
332 .unlocked_ioctl = lttng_ioctl,
333#ifdef CONFIG_COMPAT
334 .compat_ioctl = lttng_ioctl,
335#endif
336};
337
338static
339int lttng_abi_create_channel(struct file *session_file,
340 struct lttng_kernel_channel *chan_param,
341 enum channel_type channel_type)
342{
343 struct lttng_session *session = session_file->private_data;
344 const struct file_operations *fops = NULL;
345 const char *transport_name;
346 struct lttng_channel *chan;
347 struct file *chan_file;
348 int chan_fd;
349 int ret = 0;
350
351 chan_fd = get_unused_fd();
352 if (chan_fd < 0) {
353 ret = chan_fd;
354 goto fd_error;
355 }
356 switch (channel_type) {
357 case PER_CPU_CHANNEL:
358 fops = &lttng_channel_fops;
359 break;
360 case METADATA_CHANNEL:
361 fops = &lttng_metadata_fops;
362 break;
363 }
364
365 chan_file = anon_inode_getfile("[lttng_channel]",
366 fops,
367 NULL, O_RDWR);
368 if (IS_ERR(chan_file)) {
369 ret = PTR_ERR(chan_file);
370 goto file_error;
371 }
372 switch (channel_type) {
373 case PER_CPU_CHANNEL:
374 if (chan_param->output == LTTNG_KERNEL_SPLICE) {
375 transport_name = chan_param->overwrite ?
376 "relay-overwrite" : "relay-discard";
377 } else if (chan_param->output == LTTNG_KERNEL_MMAP) {
378 transport_name = chan_param->overwrite ?
379 "relay-overwrite-mmap" : "relay-discard-mmap";
380 } else {
381 return -EINVAL;
382 }
383 break;
384 case METADATA_CHANNEL:
385 if (chan_param->output == LTTNG_KERNEL_SPLICE)
386 transport_name = "relay-metadata";
387 else if (chan_param->output == LTTNG_KERNEL_MMAP)
388 transport_name = "relay-metadata-mmap";
389 else
390 return -EINVAL;
391 break;
392 default:
393 transport_name = "<unknown>";
394 break;
395 }
396 /*
397 * We tolerate no failure path after channel creation. It will stay
398 * invariant for the rest of the session.
399 */
400 chan = lttng_channel_create(session, transport_name, NULL,
401 chan_param->subbuf_size,
402 chan_param->num_subbuf,
403 chan_param->switch_timer_interval,
404 chan_param->read_timer_interval,
405 channel_type);
406 if (!chan) {
407 ret = -EINVAL;
408 goto chan_error;
409 }
410 chan->file = chan_file;
411 chan_file->private_data = chan;
412 fd_install(chan_fd, chan_file);
413 atomic_long_inc(&session_file->f_count);
414
415 return chan_fd;
416
417chan_error:
418 fput(chan_file);
419file_error:
420 put_unused_fd(chan_fd);
421fd_error:
422 return ret;
423}
424
425/**
426 * lttng_session_ioctl - lttng session fd ioctl
427 *
428 * @file: the file
429 * @cmd: the command
430 * @arg: command arg
431 *
432 * This ioctl implements lttng commands:
433 * LTTNG_KERNEL_CHANNEL
434 * Returns a LTTng channel file descriptor
435 * LTTNG_KERNEL_ENABLE
436 * Enables tracing for a session (weak enable)
437 * LTTNG_KERNEL_DISABLE
438 * Disables tracing for a session (strong disable)
439 * LTTNG_KERNEL_METADATA
440 * Returns a LTTng metadata file descriptor
441 *
442 * The returned channel will be deleted when its file descriptor is closed.
443 */
444static
445long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
446{
447 struct lttng_session *session = file->private_data;
448
449 switch (cmd) {
450 case LTTNG_KERNEL_OLD_CHANNEL:
451 {
452 struct lttng_kernel_channel chan_param;
453 struct lttng_kernel_old_channel old_chan_param;
454
455 if (copy_from_user(&old_chan_param,
456 (struct lttng_kernel_old_channel __user *) arg,
457 sizeof(struct lttng_kernel_old_channel)))
458 return -EFAULT;
459 chan_param.overwrite = old_chan_param.overwrite;
460 chan_param.subbuf_size = old_chan_param.subbuf_size;
461 chan_param.num_subbuf = old_chan_param.num_subbuf;
462 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
463 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
464 chan_param.output = old_chan_param.output;
465
466 return lttng_abi_create_channel(file, &chan_param,
467 PER_CPU_CHANNEL);
468 }
469 case LTTNG_KERNEL_CHANNEL:
470 {
471 struct lttng_kernel_channel chan_param;
472
473 if (copy_from_user(&chan_param,
474 (struct lttng_kernel_channel __user *) arg,
475 sizeof(struct lttng_kernel_channel)))
476 return -EFAULT;
477 return lttng_abi_create_channel(file, &chan_param,
478 PER_CPU_CHANNEL);
479 }
480 case LTTNG_KERNEL_OLD_SESSION_START:
481 case LTTNG_KERNEL_OLD_ENABLE:
482 case LTTNG_KERNEL_SESSION_START:
483 case LTTNG_KERNEL_ENABLE:
484 return lttng_session_enable(session);
485 case LTTNG_KERNEL_OLD_SESSION_STOP:
486 case LTTNG_KERNEL_OLD_DISABLE:
487 case LTTNG_KERNEL_SESSION_STOP:
488 case LTTNG_KERNEL_DISABLE:
489 return lttng_session_disable(session);
490 case LTTNG_KERNEL_OLD_METADATA:
491 {
492 struct lttng_kernel_channel chan_param;
493 struct lttng_kernel_old_channel old_chan_param;
494
495 if (copy_from_user(&old_chan_param,
496 (struct lttng_kernel_old_channel __user *) arg,
497 sizeof(struct lttng_kernel_old_channel)))
498 return -EFAULT;
499 chan_param.overwrite = old_chan_param.overwrite;
500 chan_param.subbuf_size = old_chan_param.subbuf_size;
501 chan_param.num_subbuf = old_chan_param.num_subbuf;
502 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
503 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
504 chan_param.output = old_chan_param.output;
505
506 return lttng_abi_create_channel(file, &chan_param,
507 METADATA_CHANNEL);
508 }
509 case LTTNG_KERNEL_METADATA:
510 {
511 struct lttng_kernel_channel chan_param;
512
513 if (copy_from_user(&chan_param,
514 (struct lttng_kernel_channel __user *) arg,
515 sizeof(struct lttng_kernel_channel)))
516 return -EFAULT;
517 return lttng_abi_create_channel(file, &chan_param,
518 METADATA_CHANNEL);
519 }
520 default:
521 return -ENOIOCTLCMD;
522 }
523}
524
525/*
526 * Called when the last file reference is dropped.
527 *
528 * Big fat note: channels and events are invariant for the whole session after
529 * their creation. So this session destruction also destroys all channel and
530 * event structures specific to this session (they are not destroyed when their
531 * individual file is released).
532 */
533static
534int lttng_session_release(struct inode *inode, struct file *file)
535{
536 struct lttng_session *session = file->private_data;
537
538 if (session)
539 lttng_session_destroy(session);
540 return 0;
541}
542
543static const struct file_operations lttng_session_fops = {
544 .owner = THIS_MODULE,
545 .release = lttng_session_release,
546 .unlocked_ioctl = lttng_session_ioctl,
547#ifdef CONFIG_COMPAT
548 .compat_ioctl = lttng_session_ioctl,
549#endif
550};
551
552/**
553 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
554 * @filp: the file
555 * @wait: poll table
556 *
557 * Handles the poll operations for the metadata channels.
558 */
559static
560unsigned int lttng_metadata_ring_buffer_poll(struct file *filp,
561 poll_table *wait)
562{
563 struct lttng_metadata_stream *stream = filp->private_data;
564 struct lib_ring_buffer *buf = stream->priv;
565 int finalized;
566 unsigned int mask = 0;
567
568 if (filp->f_mode & FMODE_READ) {
569 poll_wait_set_exclusive(wait);
570 poll_wait(filp, &stream->read_wait, wait);
571
572 finalized = stream->finalized;
573
574 /*
575 * lib_ring_buffer_is_finalized() contains a smp_rmb()
576 * ordering finalized load before offsets loads.
577 */
578 WARN_ON(atomic_long_read(&buf->active_readers) != 1);
579
580 if (finalized)
581 mask |= POLLHUP;
582
583 if (stream->metadata_cache->metadata_written >
584 stream->metadata_out)
585 mask |= POLLIN;
586 }
587
588 return mask;
589}
590
591static
592void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file *filp,
593 unsigned int cmd, unsigned long arg)
594{
595 struct lttng_metadata_stream *stream = filp->private_data;
596
597 stream->metadata_out = stream->metadata_in;
598}
599
600static
601long lttng_metadata_ring_buffer_ioctl(struct file *filp,
602 unsigned int cmd, unsigned long arg)
603{
604 int ret;
605 struct lttng_metadata_stream *stream = filp->private_data;
606 struct lib_ring_buffer *buf = stream->priv;
607
608 switch (cmd) {
609 case RING_BUFFER_GET_NEXT_SUBBUF:
610 {
611 struct lttng_metadata_stream *stream = filp->private_data;
612 struct lib_ring_buffer *buf = stream->priv;
613 struct channel *chan = buf->backend.chan;
614
615 ret = lttng_metadata_output_channel(stream, chan);
616 if (ret > 0) {
617 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
618 ret = 0;
619 } else if (ret < 0)
620 goto err;
621 break;
622 }
623 case RING_BUFFER_GET_SUBBUF:
624 {
625 /*
626 * Random access is not allowed for metadata channel.
627 */
628 return -ENOSYS;
629 }
630 case RING_BUFFER_FLUSH:
631 {
632 struct lttng_metadata_stream *stream = filp->private_data;
633 struct lib_ring_buffer *buf = stream->priv;
634 struct channel *chan = buf->backend.chan;
635
636 /*
637 * Before doing the actual ring buffer flush, write up to one
638 * packet of metadata in the ring buffer.
639 */
640 ret = lttng_metadata_output_channel(stream, chan);
641 if (ret < 0)
642 goto err;
643 break;
644 }
645 default:
646 break;
647 }
648 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
649
650 /* Performing lib ring buffer ioctl after our own. */
651 ret = lib_ring_buffer_ioctl(filp, cmd, arg, buf);
652 if (ret < 0)
653 goto err;
654
655 switch (cmd) {
656 case RING_BUFFER_PUT_NEXT_SUBBUF:
657 {
658 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
659 cmd, arg);
660 break;
661 }
662 default:
663 break;
664 }
665err:
666 return ret;
667}
668
669#ifdef CONFIG_COMPAT
670static
671long lttng_metadata_ring_buffer_compat_ioctl(struct file *filp,
672 unsigned int cmd, unsigned long arg)
673{
674 int ret;
675 struct lttng_metadata_stream *stream = filp->private_data;
676 struct lib_ring_buffer *buf = stream->priv;
677
678 switch (cmd) {
679 case RING_BUFFER_GET_NEXT_SUBBUF:
680 {
681 struct lttng_metadata_stream *stream = filp->private_data;
682 struct lib_ring_buffer *buf = stream->priv;
683 struct channel *chan = buf->backend.chan;
684
685 ret = lttng_metadata_output_channel(stream, chan);
686 if (ret > 0) {
687 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
688 ret = 0;
689 } else if (ret < 0)
690 goto err;
691 break;
692 }
693 case RING_BUFFER_GET_SUBBUF:
694 {
695 /*
696 * Random access is not allowed for metadata channel.
697 */
698 return -ENOSYS;
699 }
700 default:
701 break;
702 }
703 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
704
705 /* Performing lib ring buffer ioctl after our own. */
706 ret = lib_ring_buffer_compat_ioctl(filp, cmd, arg, buf);
707 if (ret < 0)
708 goto err;
709
710 switch (cmd) {
711 case RING_BUFFER_PUT_NEXT_SUBBUF:
712 {
713 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
714 cmd, arg);
715 break;
716 }
717 default:
718 break;
719 }
720err:
721 return ret;
722}
723#endif
724
725/*
726 * This is not used by anonymous file descriptors. This code is left
727 * there if we ever want to implement an inode with open() operation.
728 */
729static
730int lttng_metadata_ring_buffer_open(struct inode *inode, struct file *file)
731{
732 struct lttng_metadata_stream *stream = inode->i_private;
733 struct lib_ring_buffer *buf = stream->priv;
734
735 file->private_data = buf;
736 /*
737 * Since life-time of metadata cache differs from that of
738 * session, we need to keep our own reference on the transport.
739 */
740 if (!try_module_get(stream->transport->owner)) {
741 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
742 return -EBUSY;
743 }
744 return lib_ring_buffer_open(inode, file, buf);
745}
746
747static
748int lttng_metadata_ring_buffer_release(struct inode *inode, struct file *file)
749{
750 struct lttng_metadata_stream *stream = file->private_data;
751 struct lib_ring_buffer *buf = stream->priv;
752
753 kref_put(&stream->metadata_cache->refcount, metadata_cache_destroy);
754 module_put(stream->transport->owner);
755 return lib_ring_buffer_release(inode, file, buf);
756}
757
758static
759ssize_t lttng_metadata_ring_buffer_splice_read(struct file *in, loff_t *ppos,
760 struct pipe_inode_info *pipe, size_t len,
761 unsigned int flags)
762{
763 struct lttng_metadata_stream *stream = in->private_data;
764 struct lib_ring_buffer *buf = stream->priv;
765
766 return lib_ring_buffer_splice_read(in, ppos, pipe, len,
767 flags, buf);
768}
769
770static
771int lttng_metadata_ring_buffer_mmap(struct file *filp,
772 struct vm_area_struct *vma)
773{
774 struct lttng_metadata_stream *stream = filp->private_data;
775 struct lib_ring_buffer *buf = stream->priv;
776
777 return lib_ring_buffer_mmap(filp, vma, buf);
778}
779
780static
781const struct file_operations lttng_metadata_ring_buffer_file_operations = {
782 .owner = THIS_MODULE,
783 .open = lttng_metadata_ring_buffer_open,
784 .release = lttng_metadata_ring_buffer_release,
785 .poll = lttng_metadata_ring_buffer_poll,
786 .splice_read = lttng_metadata_ring_buffer_splice_read,
787 .mmap = lttng_metadata_ring_buffer_mmap,
788 .unlocked_ioctl = lttng_metadata_ring_buffer_ioctl,
789 .llseek = vfs_lib_ring_buffer_no_llseek,
790#ifdef CONFIG_COMPAT
791 .compat_ioctl = lttng_metadata_ring_buffer_compat_ioctl,
792#endif
793};
794
795static
796int lttng_abi_create_stream_fd(struct file *channel_file, void *stream_priv,
797 const struct file_operations *fops)
798{
799 int stream_fd, ret;
800 struct file *stream_file;
801
802 stream_fd = get_unused_fd();
803 if (stream_fd < 0) {
804 ret = stream_fd;
805 goto fd_error;
806 }
807 stream_file = anon_inode_getfile("[lttng_stream]", fops,
808 stream_priv, O_RDWR);
809 if (IS_ERR(stream_file)) {
810 ret = PTR_ERR(stream_file);
811 goto file_error;
812 }
813 /*
814 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
815 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
816 * file descriptor, so we set FMODE_PREAD here.
817 */
818 stream_file->f_mode |= FMODE_PREAD;
819 fd_install(stream_fd, stream_file);
820 /*
821 * The stream holds a reference to the channel within the generic ring
822 * buffer library, so no need to hold a refcount on the channel and
823 * session files here.
824 */
825 return stream_fd;
826
827file_error:
828 put_unused_fd(stream_fd);
829fd_error:
830 return ret;
831}
832
833static
834int lttng_abi_open_stream(struct file *channel_file)
835{
836 struct lttng_channel *channel = channel_file->private_data;
837 struct lib_ring_buffer *buf;
838 int ret;
839 void *stream_priv;
840
841 buf = channel->ops->buffer_read_open(channel->chan);
842 if (!buf)
843 return -ENOENT;
844
845 stream_priv = buf;
846 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
847 &lttng_stream_ring_buffer_file_operations);
848 if (ret < 0)
849 goto fd_error;
850
851 return ret;
852
853fd_error:
854 channel->ops->buffer_read_close(buf);
855 return ret;
856}
857
858static
859int lttng_abi_open_metadata_stream(struct file *channel_file)
860{
861 struct lttng_channel *channel = channel_file->private_data;
862 struct lttng_session *session = channel->session;
863 struct lib_ring_buffer *buf;
864 int ret;
865 struct lttng_metadata_stream *metadata_stream;
866 void *stream_priv;
867
868 buf = channel->ops->buffer_read_open(channel->chan);
869 if (!buf)
870 return -ENOENT;
871
872 metadata_stream = kzalloc(sizeof(struct lttng_metadata_stream),
873 GFP_KERNEL);
874 if (!metadata_stream) {
875 ret = -ENOMEM;
876 goto nomem;
877 }
878 metadata_stream->metadata_cache = session->metadata_cache;
879 init_waitqueue_head(&metadata_stream->read_wait);
880 metadata_stream->priv = buf;
881 stream_priv = metadata_stream;
882 metadata_stream->transport = channel->transport;
883 mutex_init(&metadata_stream->lock);
884
885 /*
886 * Since life-time of metadata cache differs from that of
887 * session, we need to keep our own reference on the transport.
888 */
889 if (!try_module_get(metadata_stream->transport->owner)) {
890 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
891 ret = -EINVAL;
892 goto notransport;
893 }
894
895 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
896 &lttng_metadata_ring_buffer_file_operations);
897 if (ret < 0)
898 goto fd_error;
899
900 kref_get(&session->metadata_cache->refcount);
901 list_add(&metadata_stream->list,
902 &session->metadata_cache->metadata_stream);
903 return ret;
904
905fd_error:
906 module_put(metadata_stream->transport->owner);
907notransport:
908 kfree(metadata_stream);
909nomem:
910 channel->ops->buffer_read_close(buf);
911 return ret;
912}
913
914static
915int lttng_abi_create_event(struct file *channel_file,
916 struct lttng_kernel_event *event_param)
917{
918 struct lttng_channel *channel = channel_file->private_data;
919 struct lttng_event *event;
920 int event_fd, ret;
921 struct file *event_file;
922
923 event_param->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
924 switch (event_param->instrumentation) {
925 case LTTNG_KERNEL_KRETPROBE:
926 event_param->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
927 break;
928 case LTTNG_KERNEL_KPROBE:
929 event_param->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
930 break;
931 case LTTNG_KERNEL_FUNCTION:
932 event_param->u.ftrace.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
933 break;
934 default:
935 break;
936 }
937 switch (event_param->instrumentation) {
938 default:
939 event_fd = get_unused_fd();
940 if (event_fd < 0) {
941 ret = event_fd;
942 goto fd_error;
943 }
944 event_file = anon_inode_getfile("[lttng_event]",
945 &lttng_event_fops,
946 NULL, O_RDWR);
947 if (IS_ERR(event_file)) {
948 ret = PTR_ERR(event_file);
949 goto file_error;
950 }
951 /*
952 * We tolerate no failure path after event creation. It
953 * will stay invariant for the rest of the session.
954 */
955 event = lttng_event_create(channel, event_param, NULL, NULL);
956 WARN_ON_ONCE(!event);
957 if (IS_ERR(event)) {
958 ret = PTR_ERR(event);
959 goto event_error;
960 }
961 event_file->private_data = event;
962 fd_install(event_fd, event_file);
963 /* The event holds a reference on the channel */
964 atomic_long_inc(&channel_file->f_count);
965 break;
966 case LTTNG_KERNEL_SYSCALL:
967 ret = lttng_syscalls_register(channel, NULL);
968 if (ret)
969 goto fd_error;
970 event_fd = 0;
971 if (event_param->u.syscall.enable) {
972 ret = lttng_syscall_filter_enable(channel,
973 event_param->name[0] == '\0' ?
974 NULL : event_param->name);
975 if (ret)
976 goto fd_error;
977
978 } else {
979 ret = lttng_syscall_filter_disable(channel,
980 event_param->name[0] == '\0' ?
981 NULL : event_param->name);
982 if (ret)
983 goto fd_error;
984 }
985 break;
986 }
987 return event_fd;
988
989event_error:
990 fput(event_file);
991file_error:
992 put_unused_fd(event_fd);
993fd_error:
994 return ret;
995}
996
997/**
998 * lttng_channel_ioctl - lttng syscall through ioctl
999 *
1000 * @file: the file
1001 * @cmd: the command
1002 * @arg: command arg
1003 *
1004 * This ioctl implements lttng commands:
1005 * LTTNG_KERNEL_STREAM
1006 * Returns an event stream file descriptor or failure.
1007 * (typically, one event stream records events from one CPU)
1008 * LTTNG_KERNEL_EVENT
1009 * Returns an event file descriptor or failure.
1010 * LTTNG_KERNEL_CONTEXT
1011 * Prepend a context field to each event in the channel
1012 * LTTNG_KERNEL_ENABLE
1013 * Enable recording for events in this channel (weak enable)
1014 * LTTNG_KERNEL_DISABLE
1015 * Disable recording for events in this channel (strong disable)
1016 *
1017 * Channel and event file descriptors also hold a reference on the session.
1018 */
1019static
1020long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1021{
1022 struct lttng_channel *channel = file->private_data;
1023
1024 switch (cmd) {
1025 case LTTNG_KERNEL_OLD_STREAM:
1026 case LTTNG_KERNEL_STREAM:
1027 return lttng_abi_open_stream(file);
1028 case LTTNG_KERNEL_OLD_EVENT:
1029 {
1030 struct lttng_kernel_event *uevent_param;
1031 struct lttng_kernel_old_event *old_uevent_param;
1032 int ret;
1033
1034 uevent_param = kmalloc(sizeof(struct lttng_kernel_event),
1035 GFP_KERNEL);
1036 if (!uevent_param) {
1037 ret = -ENOMEM;
1038 goto old_event_end;
1039 }
1040 old_uevent_param = kmalloc(
1041 sizeof(struct lttng_kernel_old_event),
1042 GFP_KERNEL);
1043 if (!old_uevent_param) {
1044 ret = -ENOMEM;
1045 goto old_event_error_free_param;
1046 }
1047 if (copy_from_user(old_uevent_param,
1048 (struct lttng_kernel_old_event __user *) arg,
1049 sizeof(struct lttng_kernel_old_event))) {
1050 ret = -EFAULT;
1051 goto old_event_error_free_old_param;
1052 }
1053
1054 memcpy(uevent_param->name, old_uevent_param->name,
1055 sizeof(uevent_param->name));
1056 uevent_param->instrumentation =
1057 old_uevent_param->instrumentation;
1058
1059 switch (old_uevent_param->instrumentation) {
1060 case LTTNG_KERNEL_KPROBE:
1061 uevent_param->u.kprobe.addr =
1062 old_uevent_param->u.kprobe.addr;
1063 uevent_param->u.kprobe.offset =
1064 old_uevent_param->u.kprobe.offset;
1065 memcpy(uevent_param->u.kprobe.symbol_name,
1066 old_uevent_param->u.kprobe.symbol_name,
1067 sizeof(uevent_param->u.kprobe.symbol_name));
1068 break;
1069 case LTTNG_KERNEL_KRETPROBE:
1070 uevent_param->u.kretprobe.addr =
1071 old_uevent_param->u.kretprobe.addr;
1072 uevent_param->u.kretprobe.offset =
1073 old_uevent_param->u.kretprobe.offset;
1074 memcpy(uevent_param->u.kretprobe.symbol_name,
1075 old_uevent_param->u.kretprobe.symbol_name,
1076 sizeof(uevent_param->u.kretprobe.symbol_name));
1077 break;
1078 case LTTNG_KERNEL_FUNCTION:
1079 memcpy(uevent_param->u.ftrace.symbol_name,
1080 old_uevent_param->u.ftrace.symbol_name,
1081 sizeof(uevent_param->u.ftrace.symbol_name));
1082 break;
1083 default:
1084 break;
1085 }
1086 ret = lttng_abi_create_event(file, uevent_param);
1087
1088old_event_error_free_old_param:
1089 kfree(old_uevent_param);
1090old_event_error_free_param:
1091 kfree(uevent_param);
1092old_event_end:
1093 return ret;
1094 }
1095 case LTTNG_KERNEL_EVENT:
1096 {
1097 struct lttng_kernel_event uevent_param;
1098
1099 if (copy_from_user(&uevent_param,
1100 (struct lttng_kernel_event __user *) arg,
1101 sizeof(uevent_param)))
1102 return -EFAULT;
1103 return lttng_abi_create_event(file, &uevent_param);
1104 }
1105 case LTTNG_KERNEL_OLD_CONTEXT:
1106 {
1107 struct lttng_kernel_context *ucontext_param;
1108 struct lttng_kernel_old_context *old_ucontext_param;
1109 int ret;
1110
1111 ucontext_param = kmalloc(sizeof(struct lttng_kernel_context),
1112 GFP_KERNEL);
1113 if (!ucontext_param) {
1114 ret = -ENOMEM;
1115 goto old_ctx_end;
1116 }
1117 old_ucontext_param = kmalloc(sizeof(struct lttng_kernel_old_context),
1118 GFP_KERNEL);
1119 if (!old_ucontext_param) {
1120 ret = -ENOMEM;
1121 goto old_ctx_error_free_param;
1122 }
1123
1124 if (copy_from_user(old_ucontext_param,
1125 (struct lttng_kernel_old_context __user *) arg,
1126 sizeof(struct lttng_kernel_old_context))) {
1127 ret = -EFAULT;
1128 goto old_ctx_error_free_old_param;
1129 }
1130 ucontext_param->ctx = old_ucontext_param->ctx;
1131 memcpy(ucontext_param->padding, old_ucontext_param->padding,
1132 sizeof(ucontext_param->padding));
1133 /* only type that uses the union */
1134 if (old_ucontext_param->ctx == LTTNG_KERNEL_CONTEXT_PERF_COUNTER) {
1135 ucontext_param->u.perf_counter.type =
1136 old_ucontext_param->u.perf_counter.type;
1137 ucontext_param->u.perf_counter.config =
1138 old_ucontext_param->u.perf_counter.config;
1139 memcpy(ucontext_param->u.perf_counter.name,
1140 old_ucontext_param->u.perf_counter.name,
1141 sizeof(ucontext_param->u.perf_counter.name));
1142 }
1143
1144 ret = lttng_abi_add_context(file,
1145 ucontext_param,
1146 &channel->ctx, channel->session);
1147
1148old_ctx_error_free_old_param:
1149 kfree(old_ucontext_param);
1150old_ctx_error_free_param:
1151 kfree(ucontext_param);
1152old_ctx_end:
1153 return ret;
1154 }
1155 case LTTNG_KERNEL_CONTEXT:
1156 {
1157 struct lttng_kernel_context ucontext_param;
1158
1159 if (copy_from_user(&ucontext_param,
1160 (struct lttng_kernel_context __user *) arg,
1161 sizeof(ucontext_param)))
1162 return -EFAULT;
1163 return lttng_abi_add_context(file,
1164 &ucontext_param,
1165 &channel->ctx, channel->session);
1166 }
1167 case LTTNG_KERNEL_OLD_ENABLE:
1168 case LTTNG_KERNEL_ENABLE:
1169 return lttng_channel_enable(channel);
1170 case LTTNG_KERNEL_OLD_DISABLE:
1171 case LTTNG_KERNEL_DISABLE:
1172 return lttng_channel_disable(channel);
1173 default:
1174 return -ENOIOCTLCMD;
1175 }
1176
1177}
1178
1179/**
1180 * lttng_metadata_ioctl - lttng syscall through ioctl
1181 *
1182 * @file: the file
1183 * @cmd: the command
1184 * @arg: command arg
1185 *
1186 * This ioctl implements lttng commands:
1187 * LTTNG_KERNEL_STREAM
1188 * Returns an event stream file descriptor or failure.
1189 *
1190 * Channel and event file descriptors also hold a reference on the session.
1191 */
1192static
1193long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1194{
1195 switch (cmd) {
1196 case LTTNG_KERNEL_OLD_STREAM:
1197 case LTTNG_KERNEL_STREAM:
1198 return lttng_abi_open_metadata_stream(file);
1199 default:
1200 return -ENOIOCTLCMD;
1201 }
1202}
1203
1204/**
1205 * lttng_channel_poll - lttng stream addition/removal monitoring
1206 *
1207 * @file: the file
1208 * @wait: poll table
1209 */
1210unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
1211{
1212 struct lttng_channel *channel = file->private_data;
1213 unsigned int mask = 0;
1214
1215 if (file->f_mode & FMODE_READ) {
1216 poll_wait_set_exclusive(wait);
1217 poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
1218 wait);
1219
1220 if (channel->ops->is_disabled(channel->chan))
1221 return POLLERR;
1222 if (channel->ops->is_finalized(channel->chan))
1223 return POLLHUP;
1224 if (channel->ops->buffer_has_read_closed_stream(channel->chan))
1225 return POLLIN | POLLRDNORM;
1226 return 0;
1227 }
1228 return mask;
1229
1230}
1231
1232static
1233int lttng_channel_release(struct inode *inode, struct file *file)
1234{
1235 struct lttng_channel *channel = file->private_data;
1236
1237 if (channel)
1238 fput(channel->session->file);
1239 return 0;
1240}
1241
1242static
1243int lttng_metadata_channel_release(struct inode *inode, struct file *file)
1244{
1245 struct lttng_channel *channel = file->private_data;
1246
1247 if (channel) {
1248 lttng_metadata_channel_destroy(channel);
1249 fput(channel->session->file);
1250 }
1251
1252 return 0;
1253}
1254
1255static const struct file_operations lttng_channel_fops = {
1256 .owner = THIS_MODULE,
1257 .release = lttng_channel_release,
1258 .poll = lttng_channel_poll,
1259 .unlocked_ioctl = lttng_channel_ioctl,
1260#ifdef CONFIG_COMPAT
1261 .compat_ioctl = lttng_channel_ioctl,
1262#endif
1263};
1264
1265static const struct file_operations lttng_metadata_fops = {
1266 .owner = THIS_MODULE,
1267 .release = lttng_metadata_channel_release,
1268 .unlocked_ioctl = lttng_metadata_ioctl,
1269#ifdef CONFIG_COMPAT
1270 .compat_ioctl = lttng_metadata_ioctl,
1271#endif
1272};
1273
1274/**
1275 * lttng_event_ioctl - lttng syscall through ioctl
1276 *
1277 * @file: the file
1278 * @cmd: the command
1279 * @arg: command arg
1280 *
1281 * This ioctl implements lttng commands:
1282 * LTTNG_KERNEL_CONTEXT
1283 * Prepend a context field to each record of this event
1284 * LTTNG_KERNEL_ENABLE
1285 * Enable recording for this event (weak enable)
1286 * LTTNG_KERNEL_DISABLE
1287 * Disable recording for this event (strong disable)
1288 */
1289static
1290long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1291{
1292 struct lttng_event *event = file->private_data;
1293
1294 switch (cmd) {
1295 case LTTNG_KERNEL_OLD_CONTEXT:
1296 {
1297 struct lttng_kernel_context *ucontext_param;
1298 struct lttng_kernel_old_context *old_ucontext_param;
1299 int ret;
1300
1301 ucontext_param = kmalloc(sizeof(struct lttng_kernel_context),
1302 GFP_KERNEL);
1303 if (!ucontext_param) {
1304 ret = -ENOMEM;
1305 goto old_ctx_end;
1306 }
1307 old_ucontext_param = kmalloc(sizeof(struct lttng_kernel_old_context),
1308 GFP_KERNEL);
1309 if (!old_ucontext_param) {
1310 ret = -ENOMEM;
1311 goto old_ctx_error_free_param;
1312 }
1313
1314 if (copy_from_user(old_ucontext_param,
1315 (struct lttng_kernel_old_context __user *) arg,
1316 sizeof(struct lttng_kernel_old_context))) {
1317 ret = -EFAULT;
1318 goto old_ctx_error_free_old_param;
1319 }
1320 ucontext_param->ctx = old_ucontext_param->ctx;
1321 memcpy(ucontext_param->padding, old_ucontext_param->padding,
1322 sizeof(ucontext_param->padding));
1323 /* only type that uses the union */
1324 if (old_ucontext_param->ctx == LTTNG_KERNEL_CONTEXT_PERF_COUNTER) {
1325 ucontext_param->u.perf_counter.type =
1326 old_ucontext_param->u.perf_counter.type;
1327 ucontext_param->u.perf_counter.config =
1328 old_ucontext_param->u.perf_counter.config;
1329 memcpy(ucontext_param->u.perf_counter.name,
1330 old_ucontext_param->u.perf_counter.name,
1331 sizeof(ucontext_param->u.perf_counter.name));
1332 }
1333
1334 ret = lttng_abi_add_context(file,
1335 ucontext_param,
1336 &event->ctx, event->chan->session);
1337
1338old_ctx_error_free_old_param:
1339 kfree(old_ucontext_param);
1340old_ctx_error_free_param:
1341 kfree(ucontext_param);
1342old_ctx_end:
1343 return ret;
1344 }
1345 case LTTNG_KERNEL_CONTEXT:
1346 {
1347 struct lttng_kernel_context ucontext_param;
1348
1349 if (copy_from_user(&ucontext_param,
1350 (struct lttng_kernel_context __user *) arg,
1351 sizeof(ucontext_param)))
1352 return -EFAULT;
1353 return lttng_abi_add_context(file,
1354 &ucontext_param,
1355 &event->ctx, event->chan->session);
1356 }
1357 case LTTNG_KERNEL_OLD_ENABLE:
1358 case LTTNG_KERNEL_ENABLE:
1359 return lttng_event_enable(event);
1360 case LTTNG_KERNEL_OLD_DISABLE:
1361 case LTTNG_KERNEL_DISABLE:
1362 return lttng_event_disable(event);
1363 default:
1364 return -ENOIOCTLCMD;
1365 }
1366}
1367
1368static
1369int lttng_event_release(struct inode *inode, struct file *file)
1370{
1371 struct lttng_event *event = file->private_data;
1372
1373 if (event)
1374 fput(event->chan->file);
1375 return 0;
1376}
1377
1378/* TODO: filter control ioctl */
1379static const struct file_operations lttng_event_fops = {
1380 .owner = THIS_MODULE,
1381 .release = lttng_event_release,
1382 .unlocked_ioctl = lttng_event_ioctl,
1383#ifdef CONFIG_COMPAT
1384 .compat_ioctl = lttng_event_ioctl,
1385#endif
1386};
1387
1388static int put_u64(uint64_t val, unsigned long arg)
1389{
1390 return put_user(val, (uint64_t __user *) arg);
1391}
1392
1393static long lttng_stream_ring_buffer_ioctl(struct file *filp,
1394 unsigned int cmd, unsigned long arg)
1395{
1396 struct lib_ring_buffer *buf = filp->private_data;
1397 struct channel *chan = buf->backend.chan;
1398 const struct lib_ring_buffer_config *config = &chan->backend.config;
1399 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
1400 int ret;
1401
1402 if (atomic_read(&chan->record_disabled))
1403 return -EIO;
1404
1405 switch (cmd) {
1406 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN:
1407 {
1408 uint64_t ts;
1409
1410 ret = ops->timestamp_begin(config, buf, &ts);
1411 if (ret < 0)
1412 goto error;
1413 return put_u64(ts, arg);
1414 }
1415 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END:
1416 {
1417 uint64_t ts;
1418
1419 ret = ops->timestamp_end(config, buf, &ts);
1420 if (ret < 0)
1421 goto error;
1422 return put_u64(ts, arg);
1423 }
1424 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED:
1425 {
1426 uint64_t ed;
1427
1428 ret = ops->events_discarded(config, buf, &ed);
1429 if (ret < 0)
1430 goto error;
1431 return put_u64(ed, arg);
1432 }
1433 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE:
1434 {
1435 uint64_t cs;
1436
1437 ret = ops->content_size(config, buf, &cs);
1438 if (ret < 0)
1439 goto error;
1440 return put_u64(cs, arg);
1441 }
1442 case LTTNG_RING_BUFFER_GET_PACKET_SIZE:
1443 {
1444 uint64_t ps;
1445
1446 ret = ops->packet_size(config, buf, &ps);
1447 if (ret < 0)
1448 goto error;
1449 return put_u64(ps, arg);
1450 }
1451 case LTTNG_RING_BUFFER_GET_STREAM_ID:
1452 {
1453 uint64_t si;
1454
1455 ret = ops->stream_id(config, buf, &si);
1456 if (ret < 0)
1457 goto error;
1458 return put_u64(si, arg);
1459 }
1460 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
1461 {
1462 uint64_t ts;
1463
1464 ret = ops->current_timestamp(config, buf, &ts);
1465 if (ret < 0)
1466 goto error;
1467 return put_u64(ts, arg);
1468 }
1469 default:
1470 return lib_ring_buffer_file_operations.unlocked_ioctl(filp,
1471 cmd, arg);
1472 }
1473
1474error:
1475 return -ENOSYS;
1476}
1477
1478#ifdef CONFIG_COMPAT
1479static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
1480 unsigned int cmd, unsigned long arg)
1481{
1482 struct lib_ring_buffer *buf = filp->private_data;
1483 struct channel *chan = buf->backend.chan;
1484 const struct lib_ring_buffer_config *config = &chan->backend.config;
1485 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
1486 int ret;
1487
1488 if (atomic_read(&chan->record_disabled))
1489 return -EIO;
1490
1491 switch (cmd) {
1492 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN:
1493 {
1494 uint64_t ts;
1495
1496 ret = ops->timestamp_begin(config, buf, &ts);
1497 if (ret < 0)
1498 goto error;
1499 return put_u64(ts, arg);
1500 }
1501 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END:
1502 {
1503 uint64_t ts;
1504
1505 ret = ops->timestamp_end(config, buf, &ts);
1506 if (ret < 0)
1507 goto error;
1508 return put_u64(ts, arg);
1509 }
1510 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED:
1511 {
1512 uint64_t ed;
1513
1514 ret = ops->events_discarded(config, buf, &ed);
1515 if (ret < 0)
1516 goto error;
1517 return put_u64(ed, arg);
1518 }
1519 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE:
1520 {
1521 uint64_t cs;
1522
1523 ret = ops->content_size(config, buf, &cs);
1524 if (ret < 0)
1525 goto error;
1526 return put_u64(cs, arg);
1527 }
1528 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE:
1529 {
1530 uint64_t ps;
1531
1532 ret = ops->packet_size(config, buf, &ps);
1533 if (ret < 0)
1534 goto error;
1535 return put_u64(ps, arg);
1536 }
1537 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID:
1538 {
1539 uint64_t si;
1540
1541 ret = ops->stream_id(config, buf, &si);
1542 if (ret < 0)
1543 goto error;
1544 return put_u64(si, arg);
1545 }
1546 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
1547 {
1548 uint64_t ts;
1549
1550 ret = ops->current_timestamp(config, buf, &ts);
1551 if (ret < 0)
1552 goto error;
1553 return put_u64(ts, arg);
1554 }
1555 default:
1556 return lib_ring_buffer_file_operations.compat_ioctl(filp,
1557 cmd, arg);
1558 }
1559
1560error:
1561 return -ENOSYS;
1562}
1563#endif /* CONFIG_COMPAT */
1564
1565static void lttng_stream_override_ring_buffer_fops(void)
1566{
1567 lttng_stream_ring_buffer_file_operations.owner = THIS_MODULE;
1568 lttng_stream_ring_buffer_file_operations.open =
1569 lib_ring_buffer_file_operations.open;
1570 lttng_stream_ring_buffer_file_operations.release =
1571 lib_ring_buffer_file_operations.release;
1572 lttng_stream_ring_buffer_file_operations.poll =
1573 lib_ring_buffer_file_operations.poll;
1574 lttng_stream_ring_buffer_file_operations.splice_read =
1575 lib_ring_buffer_file_operations.splice_read;
1576 lttng_stream_ring_buffer_file_operations.mmap =
1577 lib_ring_buffer_file_operations.mmap;
1578 lttng_stream_ring_buffer_file_operations.unlocked_ioctl =
1579 lttng_stream_ring_buffer_ioctl;
1580 lttng_stream_ring_buffer_file_operations.llseek =
1581 lib_ring_buffer_file_operations.llseek;
1582#ifdef CONFIG_COMPAT
1583 lttng_stream_ring_buffer_file_operations.compat_ioctl =
1584 lttng_stream_ring_buffer_compat_ioctl;
1585#endif
1586}
1587
1588int __init lttng_abi_init(void)
1589{
1590 int ret = 0;
1591
1592 wrapper_vmalloc_sync_all();
1593 lttng_proc_dentry = proc_create_data("lttng", S_IRUSR | S_IWUSR, NULL,
1594 &lttng_fops, NULL);
1595
1596 if (!lttng_proc_dentry) {
1597 printk(KERN_ERR "Error creating LTTng control file\n");
1598 ret = -ENOMEM;
1599 goto error;
1600 }
1601 lttng_stream_override_ring_buffer_fops();
1602
1603error:
1604 return ret;
1605}
1606
1607/* No __exit annotation because used by init error path too. */
1608void lttng_abi_exit(void)
1609{
1610 if (lttng_proc_dentry)
1611 remove_proc_entry("lttng", NULL);
1612}
LTTng modules - Deliverables
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