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_out
)
550 int lttng_metadata_ring_buffer_ioctl_get_next_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 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
569 unsigned int cmd
, unsigned long arg
)
571 struct lttng_metadata_stream
*stream
= filp
->private_data
;
573 stream
->metadata_out
= stream
->metadata_in
;
577 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
578 unsigned int cmd
, unsigned long arg
)
581 struct lttng_metadata_stream
*stream
= filp
->private_data
;
582 struct lib_ring_buffer
*buf
= stream
->priv
;
585 case RING_BUFFER_GET_NEXT_SUBBUF
:
587 ret
= lttng_metadata_ring_buffer_ioctl_get_next_subbuf(filp
,
593 case RING_BUFFER_GET_SUBBUF
:
596 * Random access is not allowed for metadata channel.
603 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
605 /* Performing lib ring buffer ioctl after our own. */
606 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
611 case RING_BUFFER_PUT_NEXT_SUBBUF
:
613 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
626 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
627 unsigned int cmd
, unsigned long arg
)
630 struct lttng_metadata_stream
*stream
= filp
->private_data
;
631 struct lib_ring_buffer
*buf
= stream
->priv
;
634 case RING_BUFFER_GET_NEXT_SUBBUF
:
636 ret
= lttng_metadata_ring_buffer_ioctl_get_next_subbuf(filp
,
642 case RING_BUFFER_GET_SUBBUF
:
645 * Random access is not allowed for metadata channel.
652 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
654 /* Performing lib ring buffer ioctl after our own. */
655 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
660 case RING_BUFFER_PUT_NEXT_SUBBUF
:
662 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
675 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
677 struct lttng_metadata_stream
*stream
= inode
->i_private
;
678 struct lib_ring_buffer
*buf
= stream
->priv
;
680 file
->private_data
= buf
;
681 return lib_ring_buffer_open(inode
, file
, buf
);
685 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
687 struct lttng_metadata_stream
*stream
= file
->private_data
;
688 struct lib_ring_buffer
*buf
= stream
->priv
;
690 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
692 return lib_ring_buffer_release(inode
, file
, buf
);
696 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
697 struct pipe_inode_info
*pipe
, size_t len
,
700 struct lttng_metadata_stream
*stream
= in
->private_data
;
701 struct lib_ring_buffer
*buf
= stream
->priv
;
703 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
708 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
709 struct vm_area_struct
*vma
)
711 struct lttng_metadata_stream
*stream
= filp
->private_data
;
712 struct lib_ring_buffer
*buf
= stream
->priv
;
714 return lib_ring_buffer_mmap(filp
, vma
, buf
);
718 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
719 .owner
= THIS_MODULE
,
720 .open
= lttng_metadata_ring_buffer_open
,
721 .release
= lttng_metadata_ring_buffer_release
,
722 .poll
= lttng_metadata_ring_buffer_poll
,
723 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
724 .mmap
= lttng_metadata_ring_buffer_mmap
,
725 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
726 .llseek
= vfs_lib_ring_buffer_no_llseek
,
728 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
733 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
734 const struct file_operations
*fops
)
737 struct file
*stream_file
;
739 stream_fd
= get_unused_fd();
744 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
745 stream_priv
, O_RDWR
);
746 if (IS_ERR(stream_file
)) {
747 ret
= PTR_ERR(stream_file
);
751 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
752 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
753 * file descriptor, so we set FMODE_PREAD here.
755 stream_file
->f_mode
|= FMODE_PREAD
;
756 fd_install(stream_fd
, stream_file
);
758 * The stream holds a reference to the channel within the generic ring
759 * buffer library, so no need to hold a refcount on the channel and
760 * session files here.
765 put_unused_fd(stream_fd
);
771 int lttng_abi_open_stream(struct file
*channel_file
)
773 struct lttng_channel
*channel
= channel_file
->private_data
;
774 struct lib_ring_buffer
*buf
;
778 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
783 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
784 &lib_ring_buffer_file_operations
);
791 channel
->ops
->buffer_read_close(buf
);
796 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
798 struct lttng_channel
*channel
= channel_file
->private_data
;
799 struct lttng_session
*session
= channel
->session
;
800 struct lib_ring_buffer
*buf
;
802 struct lttng_metadata_stream
*metadata_stream
;
805 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
809 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
811 if (!metadata_stream
)
813 metadata_stream
->metadata_cache
= session
->metadata_cache
;
814 init_waitqueue_head(&metadata_stream
->read_wait
);
815 metadata_stream
->priv
= buf
;
816 stream_priv
= metadata_stream
;
817 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
818 <tng_metadata_ring_buffer_file_operations
);
822 kref_get(&session
->metadata_cache
->refcount
);
823 list_add(&metadata_stream
->list
,
824 &session
->metadata_cache
->metadata_stream
);
828 channel
->ops
->buffer_read_close(buf
);
833 int lttng_abi_create_event(struct file
*channel_file
,
834 struct lttng_kernel_event
*event_param
)
836 struct lttng_channel
*channel
= channel_file
->private_data
;
837 struct lttng_event
*event
;
839 struct file
*event_file
;
841 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
842 switch (event_param
->instrumentation
) {
843 case LTTNG_KERNEL_KRETPROBE
:
844 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
846 case LTTNG_KERNEL_KPROBE
:
847 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
849 case LTTNG_KERNEL_FUNCTION
:
850 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
855 switch (event_param
->instrumentation
) {
857 event_fd
= get_unused_fd();
862 event_file
= anon_inode_getfile("[lttng_event]",
865 if (IS_ERR(event_file
)) {
866 ret
= PTR_ERR(event_file
);
870 * We tolerate no failure path after event creation. It
871 * will stay invariant for the rest of the session.
873 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
878 event_file
->private_data
= event
;
879 fd_install(event_fd
, event_file
);
880 /* The event holds a reference on the channel */
881 atomic_long_inc(&channel_file
->f_count
);
883 case LTTNG_KERNEL_SYSCALL
:
885 * Only all-syscall tracing supported for now.
887 if (event_param
->name
[0] != '\0')
889 ret
= lttng_syscalls_register(channel
, NULL
);
900 put_unused_fd(event_fd
);
906 * lttng_channel_ioctl - lttng syscall through ioctl
912 * This ioctl implements lttng commands:
913 * LTTNG_KERNEL_STREAM
914 * Returns an event stream file descriptor or failure.
915 * (typically, one event stream records events from one CPU)
917 * Returns an event file descriptor or failure.
918 * LTTNG_KERNEL_CONTEXT
919 * Prepend a context field to each event in the channel
920 * LTTNG_KERNEL_ENABLE
921 * Enable recording for events in this channel (weak enable)
922 * LTTNG_KERNEL_DISABLE
923 * Disable recording for events in this channel (strong disable)
925 * Channel and event file descriptors also hold a reference on the session.
928 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
930 struct lttng_channel
*channel
= file
->private_data
;
933 case LTTNG_KERNEL_OLD_STREAM
:
934 case LTTNG_KERNEL_STREAM
:
935 return lttng_abi_open_stream(file
);
936 case LTTNG_KERNEL_OLD_EVENT
:
938 struct lttng_kernel_event
*uevent_param
;
939 struct lttng_kernel_old_event
*old_uevent_param
;
942 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
948 old_uevent_param
= kmalloc(
949 sizeof(struct lttng_kernel_old_event
),
951 if (!old_uevent_param
) {
953 goto old_event_error_free_param
;
955 if (copy_from_user(old_uevent_param
,
956 (struct lttng_kernel_old_event __user
*) arg
,
957 sizeof(struct lttng_kernel_old_event
))) {
959 goto old_event_error_free_old_param
;
962 memcpy(uevent_param
->name
, old_uevent_param
->name
,
963 sizeof(uevent_param
->name
));
964 uevent_param
->instrumentation
=
965 old_uevent_param
->instrumentation
;
967 switch (old_uevent_param
->instrumentation
) {
968 case LTTNG_KERNEL_KPROBE
:
969 uevent_param
->u
.kprobe
.addr
=
970 old_uevent_param
->u
.kprobe
.addr
;
971 uevent_param
->u
.kprobe
.offset
=
972 old_uevent_param
->u
.kprobe
.offset
;
973 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
974 old_uevent_param
->u
.kprobe
.symbol_name
,
975 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
977 case LTTNG_KERNEL_KRETPROBE
:
978 uevent_param
->u
.kretprobe
.addr
=
979 old_uevent_param
->u
.kretprobe
.addr
;
980 uevent_param
->u
.kretprobe
.offset
=
981 old_uevent_param
->u
.kretprobe
.offset
;
982 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
983 old_uevent_param
->u
.kretprobe
.symbol_name
,
984 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
986 case LTTNG_KERNEL_FUNCTION
:
987 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
988 old_uevent_param
->u
.ftrace
.symbol_name
,
989 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
994 ret
= lttng_abi_create_event(file
, uevent_param
);
996 old_event_error_free_old_param
:
997 kfree(old_uevent_param
);
998 old_event_error_free_param
:
1003 case LTTNG_KERNEL_EVENT
:
1005 struct lttng_kernel_event uevent_param
;
1007 if (copy_from_user(&uevent_param
,
1008 (struct lttng_kernel_event __user
*) arg
,
1009 sizeof(uevent_param
)))
1011 return lttng_abi_create_event(file
, &uevent_param
);
1013 case LTTNG_KERNEL_OLD_CONTEXT
:
1015 struct lttng_kernel_context
*ucontext_param
;
1016 struct lttng_kernel_old_context
*old_ucontext_param
;
1019 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1021 if (!ucontext_param
) {
1025 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1027 if (!old_ucontext_param
) {
1029 goto old_ctx_error_free_param
;
1032 if (copy_from_user(old_ucontext_param
,
1033 (struct lttng_kernel_old_context __user
*) arg
,
1034 sizeof(struct lttng_kernel_old_context
))) {
1036 goto old_ctx_error_free_old_param
;
1038 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1039 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1040 sizeof(ucontext_param
->padding
));
1041 /* only type that uses the union */
1042 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1043 ucontext_param
->u
.perf_counter
.type
=
1044 old_ucontext_param
->u
.perf_counter
.type
;
1045 ucontext_param
->u
.perf_counter
.config
=
1046 old_ucontext_param
->u
.perf_counter
.config
;
1047 memcpy(ucontext_param
->u
.perf_counter
.name
,
1048 old_ucontext_param
->u
.perf_counter
.name
,
1049 sizeof(ucontext_param
->u
.perf_counter
.name
));
1052 ret
= lttng_abi_add_context(file
,
1054 &channel
->ctx
, channel
->session
);
1056 old_ctx_error_free_old_param
:
1057 kfree(old_ucontext_param
);
1058 old_ctx_error_free_param
:
1059 kfree(ucontext_param
);
1063 case LTTNG_KERNEL_CONTEXT
:
1065 struct lttng_kernel_context ucontext_param
;
1067 if (copy_from_user(&ucontext_param
,
1068 (struct lttng_kernel_context __user
*) arg
,
1069 sizeof(ucontext_param
)))
1071 return lttng_abi_add_context(file
,
1073 &channel
->ctx
, channel
->session
);
1075 case LTTNG_KERNEL_OLD_ENABLE
:
1076 case LTTNG_KERNEL_ENABLE
:
1077 return lttng_channel_enable(channel
);
1078 case LTTNG_KERNEL_OLD_DISABLE
:
1079 case LTTNG_KERNEL_DISABLE
:
1080 return lttng_channel_disable(channel
);
1082 return -ENOIOCTLCMD
;
1088 * lttng_metadata_ioctl - lttng syscall through ioctl
1094 * This ioctl implements lttng commands:
1095 * LTTNG_KERNEL_STREAM
1096 * Returns an event stream file descriptor or failure.
1098 * Channel and event file descriptors also hold a reference on the session.
1101 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1104 case LTTNG_KERNEL_OLD_STREAM
:
1105 case LTTNG_KERNEL_STREAM
:
1106 return lttng_abi_open_metadata_stream(file
);
1108 return -ENOIOCTLCMD
;
1113 * lttng_channel_poll - lttng stream addition/removal monitoring
1118 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1120 struct lttng_channel
*channel
= file
->private_data
;
1121 unsigned int mask
= 0;
1123 if (file
->f_mode
& FMODE_READ
) {
1124 poll_wait_set_exclusive(wait
);
1125 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1128 if (channel
->ops
->is_disabled(channel
->chan
))
1130 if (channel
->ops
->is_finalized(channel
->chan
))
1132 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1133 return POLLIN
| POLLRDNORM
;
1141 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1143 struct lttng_channel
*channel
= file
->private_data
;
1146 fput(channel
->session
->file
);
1151 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1153 struct lttng_channel
*channel
= file
->private_data
;
1156 lttng_metadata_channel_destroy(channel
);
1157 fput(channel
->session
->file
);
1163 static const struct file_operations lttng_channel_fops
= {
1164 .owner
= THIS_MODULE
,
1165 .release
= lttng_channel_release
,
1166 .poll
= lttng_channel_poll
,
1167 .unlocked_ioctl
= lttng_channel_ioctl
,
1168 #ifdef CONFIG_COMPAT
1169 .compat_ioctl
= lttng_channel_ioctl
,
1173 static const struct file_operations lttng_metadata_fops
= {
1174 .owner
= THIS_MODULE
,
1175 .release
= lttng_metadata_channel_release
,
1176 .unlocked_ioctl
= lttng_metadata_ioctl
,
1177 #ifdef CONFIG_COMPAT
1178 .compat_ioctl
= lttng_metadata_ioctl
,
1183 * lttng_event_ioctl - lttng syscall through ioctl
1189 * This ioctl implements lttng commands:
1190 * LTTNG_KERNEL_CONTEXT
1191 * Prepend a context field to each record of this event
1192 * LTTNG_KERNEL_ENABLE
1193 * Enable recording for this event (weak enable)
1194 * LTTNG_KERNEL_DISABLE
1195 * Disable recording for this event (strong disable)
1198 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1200 struct lttng_event
*event
= file
->private_data
;
1203 case LTTNG_KERNEL_OLD_CONTEXT
:
1205 struct lttng_kernel_context
*ucontext_param
;
1206 struct lttng_kernel_old_context
*old_ucontext_param
;
1209 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1211 if (!ucontext_param
) {
1215 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1217 if (!old_ucontext_param
) {
1219 goto old_ctx_error_free_param
;
1222 if (copy_from_user(old_ucontext_param
,
1223 (struct lttng_kernel_old_context __user
*) arg
,
1224 sizeof(struct lttng_kernel_old_context
))) {
1226 goto old_ctx_error_free_old_param
;
1228 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1229 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1230 sizeof(ucontext_param
->padding
));
1231 /* only type that uses the union */
1232 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1233 ucontext_param
->u
.perf_counter
.type
=
1234 old_ucontext_param
->u
.perf_counter
.type
;
1235 ucontext_param
->u
.perf_counter
.config
=
1236 old_ucontext_param
->u
.perf_counter
.config
;
1237 memcpy(ucontext_param
->u
.perf_counter
.name
,
1238 old_ucontext_param
->u
.perf_counter
.name
,
1239 sizeof(ucontext_param
->u
.perf_counter
.name
));
1242 ret
= lttng_abi_add_context(file
,
1244 &event
->ctx
, event
->chan
->session
);
1246 old_ctx_error_free_old_param
:
1247 kfree(old_ucontext_param
);
1248 old_ctx_error_free_param
:
1249 kfree(ucontext_param
);
1253 case LTTNG_KERNEL_CONTEXT
:
1255 struct lttng_kernel_context ucontext_param
;
1257 if (copy_from_user(&ucontext_param
,
1258 (struct lttng_kernel_context __user
*) arg
,
1259 sizeof(ucontext_param
)))
1261 return lttng_abi_add_context(file
,
1263 &event
->ctx
, event
->chan
->session
);
1265 case LTTNG_KERNEL_OLD_ENABLE
:
1266 case LTTNG_KERNEL_ENABLE
:
1267 return lttng_event_enable(event
);
1268 case LTTNG_KERNEL_OLD_DISABLE
:
1269 case LTTNG_KERNEL_DISABLE
:
1270 return lttng_event_disable(event
);
1272 return -ENOIOCTLCMD
;
1277 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1279 struct lttng_event
*event
= file
->private_data
;
1282 fput(event
->chan
->file
);
1286 /* TODO: filter control ioctl */
1287 static const struct file_operations lttng_event_fops
= {
1288 .owner
= THIS_MODULE
,
1289 .release
= lttng_event_release
,
1290 .unlocked_ioctl
= lttng_event_ioctl
,
1291 #ifdef CONFIG_COMPAT
1292 .compat_ioctl
= lttng_event_ioctl
,
1296 int __init
lttng_abi_init(void)
1300 wrapper_vmalloc_sync_all();
1301 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1304 if (!lttng_proc_dentry
) {
1305 printk(KERN_ERR
"Error creating LTTng control file\n");
1313 void __exit
lttng_abi_exit(void)
1315 if (lttng_proc_dentry
)
1316 remove_proc_entry("lttng", NULL
);