6 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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.
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.
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
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.
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 "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
47 #include "wrapper/ringbuffer/vfs.h"
48 #include "wrapper/ringbuffer/backend.h"
49 #include "wrapper/ringbuffer/frontend.h"
50 #include "wrapper/poll.h"
51 #include "lttng-abi.h"
52 #include "lttng-abi-old.h"
53 #include "lttng-events.h"
54 #include "lttng-tracer.h"
57 * This is LTTng's own personal way to create a system call as an external
58 * module. We use ioctl() on /proc/lttng.
61 static struct proc_dir_entry
*lttng_proc_dentry
;
62 static const struct file_operations lttng_fops
;
63 static const struct file_operations lttng_session_fops
;
64 static const struct file_operations lttng_channel_fops
;
65 static const struct file_operations lttng_metadata_fops
;
66 static const struct file_operations lttng_event_fops
;
69 * Teardown management: opened file descriptors keep a refcount on the module,
70 * so it can only exit when all file descriptors are closed.
74 int lttng_abi_create_session(void)
76 struct lttng_session
*session
;
77 struct file
*session_file
;
80 session
= lttng_session_create();
83 session_fd
= get_unused_fd();
88 session_file
= anon_inode_getfile("[lttng_session]",
91 if (IS_ERR(session_file
)) {
92 ret
= PTR_ERR(session_file
);
95 session
->file
= session_file
;
96 fd_install(session_fd
, session_file
);
100 put_unused_fd(session_fd
);
102 lttng_session_destroy(session
);
107 int lttng_abi_tracepoint_list(void)
109 struct file
*tracepoint_list_file
;
112 file_fd
= get_unused_fd();
118 tracepoint_list_file
= anon_inode_getfile("[lttng_session]",
119 <tng_tracepoint_list_fops
,
121 if (IS_ERR(tracepoint_list_file
)) {
122 ret
= PTR_ERR(tracepoint_list_file
);
125 ret
= lttng_tracepoint_list_fops
.open(NULL
, tracepoint_list_file
);
128 fd_install(file_fd
, tracepoint_list_file
);
136 fput(tracepoint_list_file
);
138 put_unused_fd(file_fd
);
144 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version
*v
)
146 v
->major
= LTTNG_MODULES_MAJOR_VERSION
;
147 v
->minor
= LTTNG_MODULES_MINOR_VERSION
;
148 v
->patchlevel
= LTTNG_MODULES_PATCHLEVEL_VERSION
;
152 long lttng_abi_add_context(struct file
*file
,
153 struct lttng_kernel_context
*context_param
,
154 struct lttng_ctx
**ctx
, struct lttng_session
*session
)
157 if (session
->been_active
)
160 switch (context_param
->ctx
) {
161 case LTTNG_KERNEL_CONTEXT_PID
:
162 return lttng_add_pid_to_ctx(ctx
);
163 case LTTNG_KERNEL_CONTEXT_PRIO
:
164 return lttng_add_prio_to_ctx(ctx
);
165 case LTTNG_KERNEL_CONTEXT_NICE
:
166 return lttng_add_nice_to_ctx(ctx
);
167 case LTTNG_KERNEL_CONTEXT_VPID
:
168 return lttng_add_vpid_to_ctx(ctx
);
169 case LTTNG_KERNEL_CONTEXT_TID
:
170 return lttng_add_tid_to_ctx(ctx
);
171 case LTTNG_KERNEL_CONTEXT_VTID
:
172 return lttng_add_vtid_to_ctx(ctx
);
173 case LTTNG_KERNEL_CONTEXT_PPID
:
174 return lttng_add_ppid_to_ctx(ctx
);
175 case LTTNG_KERNEL_CONTEXT_VPPID
:
176 return lttng_add_vppid_to_ctx(ctx
);
177 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER
:
178 context_param
->u
.perf_counter
.name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
179 return lttng_add_perf_counter_to_ctx(context_param
->u
.perf_counter
.type
,
180 context_param
->u
.perf_counter
.config
,
181 context_param
->u
.perf_counter
.name
,
183 case LTTNG_KERNEL_CONTEXT_PROCNAME
:
184 return lttng_add_procname_to_ctx(ctx
);
185 case LTTNG_KERNEL_CONTEXT_HOSTNAME
:
186 return lttng_add_hostname_to_ctx(ctx
);
193 * lttng_ioctl - lttng syscall through ioctl
199 * This ioctl implements lttng commands:
200 * LTTNG_KERNEL_SESSION
201 * Returns a LTTng trace session file descriptor
202 * LTTNG_KERNEL_TRACER_VERSION
203 * Returns the LTTng kernel tracer version
204 * LTTNG_KERNEL_TRACEPOINT_LIST
205 * Returns a file descriptor listing available tracepoints
206 * LTTNG_KERNEL_WAIT_QUIESCENT
207 * Returns after all previously running probes have completed
209 * The returned session will be deleted when its file descriptor is closed.
212 long lttng_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
215 case LTTNG_KERNEL_OLD_SESSION
:
216 case LTTNG_KERNEL_SESSION
:
217 return lttng_abi_create_session();
218 case LTTNG_KERNEL_OLD_TRACER_VERSION
:
220 struct lttng_kernel_tracer_version v
;
221 struct lttng_kernel_old_tracer_version oldv
;
222 struct lttng_kernel_old_tracer_version
*uversion
=
223 (struct lttng_kernel_old_tracer_version __user
*) arg
;
225 lttng_abi_tracer_version(&v
);
226 oldv
.major
= v
.major
;
227 oldv
.minor
= v
.minor
;
228 oldv
.patchlevel
= v
.patchlevel
;
230 if (copy_to_user(uversion
, &oldv
, sizeof(oldv
)))
234 case LTTNG_KERNEL_TRACER_VERSION
:
236 struct lttng_kernel_tracer_version version
;
237 struct lttng_kernel_tracer_version
*uversion
=
238 (struct lttng_kernel_tracer_version __user
*) arg
;
240 lttng_abi_tracer_version(&version
);
242 if (copy_to_user(uversion
, &version
, sizeof(version
)))
246 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST
:
247 case LTTNG_KERNEL_TRACEPOINT_LIST
:
248 return lttng_abi_tracepoint_list();
249 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT
:
250 case LTTNG_KERNEL_WAIT_QUIESCENT
:
253 case LTTNG_KERNEL_OLD_CALIBRATE
:
255 struct lttng_kernel_old_calibrate __user
*ucalibrate
=
256 (struct lttng_kernel_old_calibrate __user
*) arg
;
257 struct lttng_kernel_old_calibrate old_calibrate
;
258 struct lttng_kernel_calibrate calibrate
;
261 if (copy_from_user(&old_calibrate
, ucalibrate
, sizeof(old_calibrate
)))
263 calibrate
.type
= old_calibrate
.type
;
264 ret
= lttng_calibrate(&calibrate
);
265 if (copy_to_user(ucalibrate
, &old_calibrate
, sizeof(old_calibrate
)))
269 case LTTNG_KERNEL_CALIBRATE
:
271 struct lttng_kernel_calibrate __user
*ucalibrate
=
272 (struct lttng_kernel_calibrate __user
*) arg
;
273 struct lttng_kernel_calibrate calibrate
;
276 if (copy_from_user(&calibrate
, ucalibrate
, sizeof(calibrate
)))
278 ret
= lttng_calibrate(&calibrate
);
279 if (copy_to_user(ucalibrate
, &calibrate
, sizeof(calibrate
)))
288 static const struct file_operations lttng_fops
= {
289 .owner
= THIS_MODULE
,
290 .unlocked_ioctl
= lttng_ioctl
,
292 .compat_ioctl
= lttng_ioctl
,
297 int lttng_abi_create_channel(struct file
*session_file
,
298 struct lttng_kernel_channel
*chan_param
,
299 enum channel_type channel_type
)
301 struct lttng_session
*session
= session_file
->private_data
;
302 const struct file_operations
*fops
= NULL
;
303 const char *transport_name
;
304 struct lttng_channel
*chan
;
305 struct file
*chan_file
;
309 chan_fd
= get_unused_fd();
314 switch (channel_type
) {
315 case PER_CPU_CHANNEL
:
316 fops
= <tng_channel_fops
;
318 case METADATA_CHANNEL
:
319 fops
= <tng_metadata_fops
;
323 chan_file
= anon_inode_getfile("[lttng_channel]",
326 if (IS_ERR(chan_file
)) {
327 ret
= PTR_ERR(chan_file
);
330 switch (channel_type
) {
331 case PER_CPU_CHANNEL
:
332 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
) {
333 transport_name
= chan_param
->overwrite
?
334 "relay-overwrite" : "relay-discard";
335 } else if (chan_param
->output
== LTTNG_KERNEL_MMAP
) {
336 transport_name
= chan_param
->overwrite
?
337 "relay-overwrite-mmap" : "relay-discard-mmap";
342 case METADATA_CHANNEL
:
343 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
)
344 transport_name
= "relay-metadata";
345 else if (chan_param
->output
== LTTNG_KERNEL_MMAP
)
346 transport_name
= "relay-metadata-mmap";
351 transport_name
= "<unknown>";
355 * We tolerate no failure path after channel creation. It will stay
356 * invariant for the rest of the session.
358 chan
= lttng_channel_create(session
, transport_name
, NULL
,
359 chan_param
->subbuf_size
,
360 chan_param
->num_subbuf
,
361 chan_param
->switch_timer_interval
,
362 chan_param
->read_timer_interval
,
368 chan
->file
= chan_file
;
369 chan_file
->private_data
= chan
;
370 fd_install(chan_fd
, chan_file
);
371 atomic_long_inc(&session_file
->f_count
);
378 put_unused_fd(chan_fd
);
384 * lttng_session_ioctl - lttng session fd ioctl
390 * This ioctl implements lttng commands:
391 * LTTNG_KERNEL_CHANNEL
392 * Returns a LTTng channel file descriptor
393 * LTTNG_KERNEL_ENABLE
394 * Enables tracing for a session (weak enable)
395 * LTTNG_KERNEL_DISABLE
396 * Disables tracing for a session (strong disable)
397 * LTTNG_KERNEL_METADATA
398 * Returns a LTTng metadata file descriptor
400 * The returned channel will be deleted when its file descriptor is closed.
403 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
405 struct lttng_session
*session
= file
->private_data
;
408 case LTTNG_KERNEL_OLD_CHANNEL
:
410 struct lttng_kernel_channel chan_param
;
411 struct lttng_kernel_old_channel old_chan_param
;
413 if (copy_from_user(&old_chan_param
,
414 (struct lttng_kernel_old_channel __user
*) arg
,
415 sizeof(struct lttng_kernel_old_channel
)))
417 chan_param
.overwrite
= old_chan_param
.overwrite
;
418 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
419 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
420 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
421 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
422 chan_param
.output
= old_chan_param
.output
;
424 return lttng_abi_create_channel(file
, &chan_param
,
427 case LTTNG_KERNEL_CHANNEL
:
429 struct lttng_kernel_channel chan_param
;
431 if (copy_from_user(&chan_param
,
432 (struct lttng_kernel_channel __user
*) arg
,
433 sizeof(struct lttng_kernel_channel
)))
435 return lttng_abi_create_channel(file
, &chan_param
,
438 case LTTNG_KERNEL_OLD_SESSION_START
:
439 case LTTNG_KERNEL_OLD_ENABLE
:
440 case LTTNG_KERNEL_SESSION_START
:
441 case LTTNG_KERNEL_ENABLE
:
442 return lttng_session_enable(session
);
443 case LTTNG_KERNEL_OLD_SESSION_STOP
:
444 case LTTNG_KERNEL_OLD_DISABLE
:
445 case LTTNG_KERNEL_SESSION_STOP
:
446 case LTTNG_KERNEL_DISABLE
:
447 return lttng_session_disable(session
);
448 case LTTNG_KERNEL_OLD_METADATA
:
450 struct lttng_kernel_channel chan_param
;
451 struct lttng_kernel_old_channel old_chan_param
;
453 if (copy_from_user(&old_chan_param
,
454 (struct lttng_kernel_old_channel __user
*) arg
,
455 sizeof(struct lttng_kernel_old_channel
)))
457 chan_param
.overwrite
= old_chan_param
.overwrite
;
458 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
459 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
460 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
461 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
462 chan_param
.output
= old_chan_param
.output
;
464 return lttng_abi_create_channel(file
, &chan_param
,
467 case LTTNG_KERNEL_METADATA
:
469 struct lttng_kernel_channel chan_param
;
471 if (copy_from_user(&chan_param
,
472 (struct lttng_kernel_channel __user
*) arg
,
473 sizeof(struct lttng_kernel_channel
)))
475 return lttng_abi_create_channel(file
, &chan_param
,
484 * Called when the last file reference is dropped.
486 * Big fat note: channels and events are invariant for the whole session after
487 * their creation. So this session destruction also destroys all channel and
488 * event structures specific to this session (they are not destroyed when their
489 * individual file is released).
492 int lttng_session_release(struct inode
*inode
, struct file
*file
)
494 struct lttng_session
*session
= file
->private_data
;
497 lttng_session_destroy(session
);
501 static const struct file_operations lttng_session_fops
= {
502 .owner
= THIS_MODULE
,
503 .release
= lttng_session_release
,
504 .unlocked_ioctl
= lttng_session_ioctl
,
506 .compat_ioctl
= lttng_session_ioctl
,
511 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
515 * Handles the poll operations for the metadata channels.
518 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
521 struct lttng_metadata_stream
*stream
= filp
->private_data
;
522 struct lib_ring_buffer
*buf
= stream
->priv
;
524 unsigned int mask
= 0;
526 if (filp
->f_mode
& FMODE_READ
) {
527 poll_wait_set_exclusive(wait
);
528 poll_wait(filp
, &stream
->read_wait
, wait
);
530 finalized
= stream
->finalized
;
533 * lib_ring_buffer_is_finalized() contains a smp_rmb()
534 * ordering finalized load before offsets loads.
536 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
541 if (stream
->metadata_cache
->metadata_written
>
542 stream
->metadata_cache_read
)
550 int lttng_metadata_ring_buffer_ioctl_get_subbuf(struct file
*filp
,
551 unsigned int cmd
, unsigned long arg
)
553 struct lttng_metadata_stream
*stream
= filp
->private_data
;
554 struct lib_ring_buffer
*buf
= stream
->priv
;
555 struct channel
*chan
= buf
->backend
.chan
;
556 struct lttng_channel
*lttng_chan
= channel_get_private(chan
);
559 ret
= lttng_metadata_output_channel(lttng_chan
, stream
);
561 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
568 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
569 unsigned int cmd
, unsigned long arg
)
572 struct lttng_metadata_stream
*stream
= filp
->private_data
;
573 struct lib_ring_buffer
*buf
= stream
->priv
;
576 case RING_BUFFER_GET_SUBBUF
:
577 case RING_BUFFER_GET_NEXT_SUBBUF
:
579 ret
= lttng_metadata_ring_buffer_ioctl_get_subbuf(filp
,
588 /* Performing lib ring buffer ioctl after our own. */
589 return lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
596 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
597 unsigned int cmd
, unsigned long arg
)
600 struct lttng_metadata_stream
*stream
= filp
->private_data
;
601 struct lib_ring_buffer
*buf
= stream
->priv
;
604 case RING_BUFFER_GET_SUBBUF
:
605 case RING_BUFFER_GET_NEXT_SUBBUF
:
607 ret
= lttng_metadata_ring_buffer_ioctl_get_subbuf(filp
,
616 /* Performing lib ring buffer ioctl after our own. */
617 return lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
624 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
626 struct lttng_metadata_stream
*stream
= inode
->i_private
;
627 struct lib_ring_buffer
*buf
= stream
->priv
;
629 file
->private_data
= buf
;
630 return lib_ring_buffer_open(inode
, file
, buf
);
634 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
636 struct lttng_metadata_stream
*stream
= file
->private_data
;
637 struct lib_ring_buffer
*buf
= stream
->priv
;
639 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
641 return lib_ring_buffer_release(inode
, file
, buf
);
645 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
646 struct pipe_inode_info
*pipe
, size_t len
,
649 struct lttng_metadata_stream
*stream
= in
->private_data
;
650 struct lib_ring_buffer
*buf
= stream
->priv
;
652 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
657 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
658 struct vm_area_struct
*vma
)
660 struct lttng_metadata_stream
*stream
= filp
->private_data
;
661 struct lib_ring_buffer
*buf
= stream
->priv
;
663 return lib_ring_buffer_mmap(filp
, vma
, buf
);
667 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
668 .owner
= THIS_MODULE
,
669 .open
= lttng_metadata_ring_buffer_open
,
670 .release
= lttng_metadata_ring_buffer_release
,
671 .poll
= lttng_metadata_ring_buffer_poll
,
672 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
673 .mmap
= lttng_metadata_ring_buffer_mmap
,
674 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
675 .llseek
= vfs_lib_ring_buffer_no_llseek
,
677 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
682 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
683 const struct file_operations
*fops
)
686 struct file
*stream_file
;
688 stream_fd
= get_unused_fd();
693 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
694 stream_priv
, O_RDWR
);
695 if (IS_ERR(stream_file
)) {
696 ret
= PTR_ERR(stream_file
);
700 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
701 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
702 * file descriptor, so we set FMODE_PREAD here.
704 stream_file
->f_mode
|= FMODE_PREAD
;
705 fd_install(stream_fd
, stream_file
);
707 * The stream holds a reference to the channel within the generic ring
708 * buffer library, so no need to hold a refcount on the channel and
709 * session files here.
714 put_unused_fd(stream_fd
);
720 int lttng_abi_open_stream(struct file
*channel_file
)
722 struct lttng_channel
*channel
= channel_file
->private_data
;
723 struct lib_ring_buffer
*buf
;
727 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
732 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
733 &lib_ring_buffer_file_operations
);
740 channel
->ops
->buffer_read_close(buf
);
745 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
747 struct lttng_channel
*channel
= channel_file
->private_data
;
748 struct lttng_session
*session
= channel
->session
;
749 struct lib_ring_buffer
*buf
;
751 struct lttng_metadata_stream
*metadata_stream
;
754 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
758 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
760 if (!metadata_stream
)
762 metadata_stream
->metadata_cache
= session
->metadata_cache
;
763 init_waitqueue_head(&metadata_stream
->read_wait
);
764 metadata_stream
->priv
= buf
;
765 stream_priv
= metadata_stream
;
766 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
767 <tng_metadata_ring_buffer_file_operations
);
771 kref_get(&session
->metadata_cache
->refcount
);
772 list_add(&metadata_stream
->list
,
773 &session
->metadata_cache
->metadata_stream
);
777 channel
->ops
->buffer_read_close(buf
);
782 int lttng_abi_create_event(struct file
*channel_file
,
783 struct lttng_kernel_event
*event_param
)
785 struct lttng_channel
*channel
= channel_file
->private_data
;
786 struct lttng_event
*event
;
788 struct file
*event_file
;
790 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
791 switch (event_param
->instrumentation
) {
792 case LTTNG_KERNEL_KRETPROBE
:
793 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
795 case LTTNG_KERNEL_KPROBE
:
796 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
798 case LTTNG_KERNEL_FUNCTION
:
799 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
804 switch (event_param
->instrumentation
) {
806 event_fd
= get_unused_fd();
811 event_file
= anon_inode_getfile("[lttng_event]",
814 if (IS_ERR(event_file
)) {
815 ret
= PTR_ERR(event_file
);
819 * We tolerate no failure path after event creation. It
820 * will stay invariant for the rest of the session.
822 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
827 event_file
->private_data
= event
;
828 fd_install(event_fd
, event_file
);
829 /* The event holds a reference on the channel */
830 atomic_long_inc(&channel_file
->f_count
);
832 case LTTNG_KERNEL_SYSCALL
:
834 * Only all-syscall tracing supported for now.
836 if (event_param
->name
[0] != '\0')
838 ret
= lttng_syscalls_register(channel
, NULL
);
849 put_unused_fd(event_fd
);
855 * lttng_channel_ioctl - lttng syscall through ioctl
861 * This ioctl implements lttng commands:
862 * LTTNG_KERNEL_STREAM
863 * Returns an event stream file descriptor or failure.
864 * (typically, one event stream records events from one CPU)
866 * Returns an event file descriptor or failure.
867 * LTTNG_KERNEL_CONTEXT
868 * Prepend a context field to each event in the channel
869 * LTTNG_KERNEL_ENABLE
870 * Enable recording for events in this channel (weak enable)
871 * LTTNG_KERNEL_DISABLE
872 * Disable recording for events in this channel (strong disable)
874 * Channel and event file descriptors also hold a reference on the session.
877 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
879 struct lttng_channel
*channel
= file
->private_data
;
882 case LTTNG_KERNEL_OLD_STREAM
:
883 case LTTNG_KERNEL_STREAM
:
884 return lttng_abi_open_stream(file
);
885 case LTTNG_KERNEL_OLD_EVENT
:
887 struct lttng_kernel_event
*uevent_param
;
888 struct lttng_kernel_old_event
*old_uevent_param
;
891 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
897 old_uevent_param
= kmalloc(
898 sizeof(struct lttng_kernel_old_event
),
900 if (!old_uevent_param
) {
902 goto old_event_error_free_param
;
904 if (copy_from_user(old_uevent_param
,
905 (struct lttng_kernel_old_event __user
*) arg
,
906 sizeof(struct lttng_kernel_old_event
))) {
908 goto old_event_error_free_old_param
;
911 memcpy(uevent_param
->name
, old_uevent_param
->name
,
912 sizeof(uevent_param
->name
));
913 uevent_param
->instrumentation
=
914 old_uevent_param
->instrumentation
;
916 switch (old_uevent_param
->instrumentation
) {
917 case LTTNG_KERNEL_KPROBE
:
918 uevent_param
->u
.kprobe
.addr
=
919 old_uevent_param
->u
.kprobe
.addr
;
920 uevent_param
->u
.kprobe
.offset
=
921 old_uevent_param
->u
.kprobe
.offset
;
922 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
923 old_uevent_param
->u
.kprobe
.symbol_name
,
924 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
926 case LTTNG_KERNEL_KRETPROBE
:
927 uevent_param
->u
.kretprobe
.addr
=
928 old_uevent_param
->u
.kretprobe
.addr
;
929 uevent_param
->u
.kretprobe
.offset
=
930 old_uevent_param
->u
.kretprobe
.offset
;
931 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
932 old_uevent_param
->u
.kretprobe
.symbol_name
,
933 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
935 case LTTNG_KERNEL_FUNCTION
:
936 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
937 old_uevent_param
->u
.ftrace
.symbol_name
,
938 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
943 ret
= lttng_abi_create_event(file
, uevent_param
);
945 old_event_error_free_old_param
:
946 kfree(old_uevent_param
);
947 old_event_error_free_param
:
952 case LTTNG_KERNEL_EVENT
:
954 struct lttng_kernel_event uevent_param
;
956 if (copy_from_user(&uevent_param
,
957 (struct lttng_kernel_event __user
*) arg
,
958 sizeof(uevent_param
)))
960 return lttng_abi_create_event(file
, &uevent_param
);
962 case LTTNG_KERNEL_OLD_CONTEXT
:
964 struct lttng_kernel_context
*ucontext_param
;
965 struct lttng_kernel_old_context
*old_ucontext_param
;
968 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
970 if (!ucontext_param
) {
974 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
976 if (!old_ucontext_param
) {
978 goto old_ctx_error_free_param
;
981 if (copy_from_user(old_ucontext_param
,
982 (struct lttng_kernel_old_context __user
*) arg
,
983 sizeof(struct lttng_kernel_old_context
))) {
985 goto old_ctx_error_free_old_param
;
987 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
988 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
989 sizeof(ucontext_param
->padding
));
990 /* only type that uses the union */
991 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
992 ucontext_param
->u
.perf_counter
.type
=
993 old_ucontext_param
->u
.perf_counter
.type
;
994 ucontext_param
->u
.perf_counter
.config
=
995 old_ucontext_param
->u
.perf_counter
.config
;
996 memcpy(ucontext_param
->u
.perf_counter
.name
,
997 old_ucontext_param
->u
.perf_counter
.name
,
998 sizeof(ucontext_param
->u
.perf_counter
.name
));
1001 ret
= lttng_abi_add_context(file
,
1003 &channel
->ctx
, channel
->session
);
1005 old_ctx_error_free_old_param
:
1006 kfree(old_ucontext_param
);
1007 old_ctx_error_free_param
:
1008 kfree(ucontext_param
);
1012 case LTTNG_KERNEL_CONTEXT
:
1014 struct lttng_kernel_context ucontext_param
;
1016 if (copy_from_user(&ucontext_param
,
1017 (struct lttng_kernel_context __user
*) arg
,
1018 sizeof(ucontext_param
)))
1020 return lttng_abi_add_context(file
,
1022 &channel
->ctx
, channel
->session
);
1024 case LTTNG_KERNEL_OLD_ENABLE
:
1025 case LTTNG_KERNEL_ENABLE
:
1026 return lttng_channel_enable(channel
);
1027 case LTTNG_KERNEL_OLD_DISABLE
:
1028 case LTTNG_KERNEL_DISABLE
:
1029 return lttng_channel_disable(channel
);
1031 return -ENOIOCTLCMD
;
1037 * lttng_metadata_ioctl - lttng syscall through ioctl
1043 * This ioctl implements lttng commands:
1044 * LTTNG_KERNEL_STREAM
1045 * Returns an event stream file descriptor or failure.
1047 * Channel and event file descriptors also hold a reference on the session.
1050 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1053 case LTTNG_KERNEL_OLD_STREAM
:
1054 case LTTNG_KERNEL_STREAM
:
1055 return lttng_abi_open_metadata_stream(file
);
1057 return -ENOIOCTLCMD
;
1062 * lttng_channel_poll - lttng stream addition/removal monitoring
1067 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1069 struct lttng_channel
*channel
= file
->private_data
;
1070 unsigned int mask
= 0;
1072 if (file
->f_mode
& FMODE_READ
) {
1073 poll_wait_set_exclusive(wait
);
1074 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1077 if (channel
->ops
->is_disabled(channel
->chan
))
1079 if (channel
->ops
->is_finalized(channel
->chan
))
1081 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1082 return POLLIN
| POLLRDNORM
;
1090 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1092 struct lttng_channel
*channel
= file
->private_data
;
1095 fput(channel
->session
->file
);
1100 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1102 struct lttng_channel
*channel
= file
->private_data
;
1105 lttng_metadata_channel_destroy(channel
);
1106 fput(channel
->session
->file
);
1112 static const struct file_operations lttng_channel_fops
= {
1113 .owner
= THIS_MODULE
,
1114 .release
= lttng_channel_release
,
1115 .poll
= lttng_channel_poll
,
1116 .unlocked_ioctl
= lttng_channel_ioctl
,
1117 #ifdef CONFIG_COMPAT
1118 .compat_ioctl
= lttng_channel_ioctl
,
1122 static const struct file_operations lttng_metadata_fops
= {
1123 .owner
= THIS_MODULE
,
1124 .release
= lttng_metadata_channel_release
,
1125 .unlocked_ioctl
= lttng_metadata_ioctl
,
1126 #ifdef CONFIG_COMPAT
1127 .compat_ioctl
= lttng_metadata_ioctl
,
1132 * lttng_event_ioctl - lttng syscall through ioctl
1138 * This ioctl implements lttng commands:
1139 * LTTNG_KERNEL_CONTEXT
1140 * Prepend a context field to each record of this event
1141 * LTTNG_KERNEL_ENABLE
1142 * Enable recording for this event (weak enable)
1143 * LTTNG_KERNEL_DISABLE
1144 * Disable recording for this event (strong disable)
1147 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1149 struct lttng_event
*event
= file
->private_data
;
1152 case LTTNG_KERNEL_OLD_CONTEXT
:
1154 struct lttng_kernel_context
*ucontext_param
;
1155 struct lttng_kernel_old_context
*old_ucontext_param
;
1158 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1160 if (!ucontext_param
) {
1164 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1166 if (!old_ucontext_param
) {
1168 goto old_ctx_error_free_param
;
1171 if (copy_from_user(old_ucontext_param
,
1172 (struct lttng_kernel_old_context __user
*) arg
,
1173 sizeof(struct lttng_kernel_old_context
))) {
1175 goto old_ctx_error_free_old_param
;
1177 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1178 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1179 sizeof(ucontext_param
->padding
));
1180 /* only type that uses the union */
1181 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1182 ucontext_param
->u
.perf_counter
.type
=
1183 old_ucontext_param
->u
.perf_counter
.type
;
1184 ucontext_param
->u
.perf_counter
.config
=
1185 old_ucontext_param
->u
.perf_counter
.config
;
1186 memcpy(ucontext_param
->u
.perf_counter
.name
,
1187 old_ucontext_param
->u
.perf_counter
.name
,
1188 sizeof(ucontext_param
->u
.perf_counter
.name
));
1191 ret
= lttng_abi_add_context(file
,
1193 &event
->ctx
, event
->chan
->session
);
1195 old_ctx_error_free_old_param
:
1196 kfree(old_ucontext_param
);
1197 old_ctx_error_free_param
:
1198 kfree(ucontext_param
);
1202 case LTTNG_KERNEL_CONTEXT
:
1204 struct lttng_kernel_context ucontext_param
;
1206 if (copy_from_user(&ucontext_param
,
1207 (struct lttng_kernel_context __user
*) arg
,
1208 sizeof(ucontext_param
)))
1210 return lttng_abi_add_context(file
,
1212 &event
->ctx
, event
->chan
->session
);
1214 case LTTNG_KERNEL_OLD_ENABLE
:
1215 case LTTNG_KERNEL_ENABLE
:
1216 return lttng_event_enable(event
);
1217 case LTTNG_KERNEL_OLD_DISABLE
:
1218 case LTTNG_KERNEL_DISABLE
:
1219 return lttng_event_disable(event
);
1221 return -ENOIOCTLCMD
;
1226 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1228 struct lttng_event
*event
= file
->private_data
;
1231 fput(event
->chan
->file
);
1235 /* TODO: filter control ioctl */
1236 static const struct file_operations lttng_event_fops
= {
1237 .owner
= THIS_MODULE
,
1238 .release
= lttng_event_release
,
1239 .unlocked_ioctl
= lttng_event_ioctl
,
1240 #ifdef CONFIG_COMPAT
1241 .compat_ioctl
= lttng_event_ioctl
,
1245 int __init
lttng_abi_init(void)
1249 wrapper_vmalloc_sync_all();
1250 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1253 if (!lttng_proc_dentry
) {
1254 printk(KERN_ERR
"Error creating LTTng control file\n");
1262 void __exit
lttng_abi_exit(void)
1264 if (lttng_proc_dentry
)
1265 remove_proc_entry("lttng", NULL
);