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 <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"
58 * This is LTTng's own personal way to create a system call as an external
59 * module. We use ioctl() on /proc/lttng.
62 static struct proc_dir_entry
*lttng_proc_dentry
;
63 static const struct file_operations lttng_fops
;
64 static const struct file_operations lttng_session_fops
;
65 static const struct file_operations lttng_channel_fops
;
66 static const struct file_operations lttng_metadata_fops
;
67 static const struct file_operations lttng_event_fops
;
70 * Teardown management: opened file descriptors keep a refcount on the module,
71 * so it can only exit when all file descriptors are closed.
75 int lttng_abi_create_session(void)
77 struct lttng_session
*session
;
78 struct file
*session_file
;
81 session
= lttng_session_create();
84 session_fd
= get_unused_fd();
89 session_file
= anon_inode_getfile("[lttng_session]",
92 if (IS_ERR(session_file
)) {
93 ret
= PTR_ERR(session_file
);
96 session
->file
= session_file
;
97 fd_install(session_fd
, session_file
);
101 put_unused_fd(session_fd
);
103 lttng_session_destroy(session
);
108 int lttng_abi_tracepoint_list(void)
110 struct file
*tracepoint_list_file
;
113 file_fd
= get_unused_fd();
119 tracepoint_list_file
= anon_inode_getfile("[lttng_session]",
120 <tng_tracepoint_list_fops
,
122 if (IS_ERR(tracepoint_list_file
)) {
123 ret
= PTR_ERR(tracepoint_list_file
);
126 ret
= lttng_tracepoint_list_fops
.open(NULL
, tracepoint_list_file
);
129 fd_install(file_fd
, tracepoint_list_file
);
137 fput(tracepoint_list_file
);
139 put_unused_fd(file_fd
);
145 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version
*v
)
147 v
->major
= LTTNG_MODULES_MAJOR_VERSION
;
148 v
->minor
= LTTNG_MODULES_MINOR_VERSION
;
149 v
->patchlevel
= LTTNG_MODULES_PATCHLEVEL_VERSION
;
153 long lttng_abi_add_context(struct file
*file
,
154 struct lttng_kernel_context
*context_param
,
155 struct lttng_ctx
**ctx
, struct lttng_session
*session
)
158 if (session
->been_active
)
161 switch (context_param
->ctx
) {
162 case LTTNG_KERNEL_CONTEXT_PID
:
163 return lttng_add_pid_to_ctx(ctx
);
164 case LTTNG_KERNEL_CONTEXT_PRIO
:
165 return lttng_add_prio_to_ctx(ctx
);
166 case LTTNG_KERNEL_CONTEXT_NICE
:
167 return lttng_add_nice_to_ctx(ctx
);
168 case LTTNG_KERNEL_CONTEXT_VPID
:
169 return lttng_add_vpid_to_ctx(ctx
);
170 case LTTNG_KERNEL_CONTEXT_TID
:
171 return lttng_add_tid_to_ctx(ctx
);
172 case LTTNG_KERNEL_CONTEXT_VTID
:
173 return lttng_add_vtid_to_ctx(ctx
);
174 case LTTNG_KERNEL_CONTEXT_PPID
:
175 return lttng_add_ppid_to_ctx(ctx
);
176 case LTTNG_KERNEL_CONTEXT_VPPID
:
177 return lttng_add_vppid_to_ctx(ctx
);
178 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER
:
179 context_param
->u
.perf_counter
.name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
180 return lttng_add_perf_counter_to_ctx(context_param
->u
.perf_counter
.type
,
181 context_param
->u
.perf_counter
.config
,
182 context_param
->u
.perf_counter
.name
,
184 case LTTNG_KERNEL_CONTEXT_PROCNAME
:
185 return lttng_add_procname_to_ctx(ctx
);
186 case LTTNG_KERNEL_CONTEXT_HOSTNAME
:
187 return lttng_add_hostname_to_ctx(ctx
);
194 * lttng_ioctl - lttng syscall through ioctl
200 * This ioctl implements lttng commands:
201 * LTTNG_KERNEL_SESSION
202 * Returns a LTTng trace session file descriptor
203 * LTTNG_KERNEL_TRACER_VERSION
204 * Returns the LTTng kernel tracer version
205 * LTTNG_KERNEL_TRACEPOINT_LIST
206 * Returns a file descriptor listing available tracepoints
207 * LTTNG_KERNEL_WAIT_QUIESCENT
208 * Returns after all previously running probes have completed
210 * The returned session will be deleted when its file descriptor is closed.
213 long lttng_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
216 case LTTNG_KERNEL_OLD_SESSION
:
217 case LTTNG_KERNEL_SESSION
:
218 return lttng_abi_create_session();
219 case LTTNG_KERNEL_OLD_TRACER_VERSION
:
221 struct lttng_kernel_tracer_version v
;
222 struct lttng_kernel_old_tracer_version oldv
;
223 struct lttng_kernel_old_tracer_version
*uversion
=
224 (struct lttng_kernel_old_tracer_version __user
*) arg
;
226 lttng_abi_tracer_version(&v
);
227 oldv
.major
= v
.major
;
228 oldv
.minor
= v
.minor
;
229 oldv
.patchlevel
= v
.patchlevel
;
231 if (copy_to_user(uversion
, &oldv
, sizeof(oldv
)))
235 case LTTNG_KERNEL_TRACER_VERSION
:
237 struct lttng_kernel_tracer_version version
;
238 struct lttng_kernel_tracer_version
*uversion
=
239 (struct lttng_kernel_tracer_version __user
*) arg
;
241 lttng_abi_tracer_version(&version
);
243 if (copy_to_user(uversion
, &version
, sizeof(version
)))
247 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST
:
248 case LTTNG_KERNEL_TRACEPOINT_LIST
:
249 return lttng_abi_tracepoint_list();
250 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT
:
251 case LTTNG_KERNEL_WAIT_QUIESCENT
:
254 case LTTNG_KERNEL_OLD_CALIBRATE
:
256 struct lttng_kernel_old_calibrate __user
*ucalibrate
=
257 (struct lttng_kernel_old_calibrate __user
*) arg
;
258 struct lttng_kernel_old_calibrate old_calibrate
;
259 struct lttng_kernel_calibrate calibrate
;
262 if (copy_from_user(&old_calibrate
, ucalibrate
, sizeof(old_calibrate
)))
264 calibrate
.type
= old_calibrate
.type
;
265 ret
= lttng_calibrate(&calibrate
);
266 if (copy_to_user(ucalibrate
, &old_calibrate
, sizeof(old_calibrate
)))
270 case LTTNG_KERNEL_CALIBRATE
:
272 struct lttng_kernel_calibrate __user
*ucalibrate
=
273 (struct lttng_kernel_calibrate __user
*) arg
;
274 struct lttng_kernel_calibrate calibrate
;
277 if (copy_from_user(&calibrate
, ucalibrate
, sizeof(calibrate
)))
279 ret
= lttng_calibrate(&calibrate
);
280 if (copy_to_user(ucalibrate
, &calibrate
, sizeof(calibrate
)))
289 static const struct file_operations lttng_fops
= {
290 .owner
= THIS_MODULE
,
291 .unlocked_ioctl
= lttng_ioctl
,
293 .compat_ioctl
= lttng_ioctl
,
298 int lttng_abi_create_channel(struct file
*session_file
,
299 struct lttng_kernel_channel
*chan_param
,
300 enum channel_type channel_type
)
302 struct lttng_session
*session
= session_file
->private_data
;
303 const struct file_operations
*fops
= NULL
;
304 const char *transport_name
;
305 struct lttng_channel
*chan
;
306 struct file
*chan_file
;
310 chan_fd
= get_unused_fd();
315 switch (channel_type
) {
316 case PER_CPU_CHANNEL
:
317 fops
= <tng_channel_fops
;
319 case METADATA_CHANNEL
:
320 fops
= <tng_metadata_fops
;
324 chan_file
= anon_inode_getfile("[lttng_channel]",
327 if (IS_ERR(chan_file
)) {
328 ret
= PTR_ERR(chan_file
);
331 switch (channel_type
) {
332 case PER_CPU_CHANNEL
:
333 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
) {
334 transport_name
= chan_param
->overwrite
?
335 "relay-overwrite" : "relay-discard";
336 } else if (chan_param
->output
== LTTNG_KERNEL_MMAP
) {
337 transport_name
= chan_param
->overwrite
?
338 "relay-overwrite-mmap" : "relay-discard-mmap";
343 case METADATA_CHANNEL
:
344 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
)
345 transport_name
= "relay-metadata";
346 else if (chan_param
->output
== LTTNG_KERNEL_MMAP
)
347 transport_name
= "relay-metadata-mmap";
352 transport_name
= "<unknown>";
356 * We tolerate no failure path after channel creation. It will stay
357 * invariant for the rest of the session.
359 chan
= lttng_channel_create(session
, transport_name
, NULL
,
360 chan_param
->subbuf_size
,
361 chan_param
->num_subbuf
,
362 chan_param
->switch_timer_interval
,
363 chan_param
->read_timer_interval
,
369 chan
->file
= chan_file
;
370 chan_file
->private_data
= chan
;
371 fd_install(chan_fd
, chan_file
);
372 atomic_long_inc(&session_file
->f_count
);
379 put_unused_fd(chan_fd
);
385 * lttng_session_ioctl - lttng session fd ioctl
391 * This ioctl implements lttng commands:
392 * LTTNG_KERNEL_CHANNEL
393 * Returns a LTTng channel file descriptor
394 * LTTNG_KERNEL_ENABLE
395 * Enables tracing for a session (weak enable)
396 * LTTNG_KERNEL_DISABLE
397 * Disables tracing for a session (strong disable)
398 * LTTNG_KERNEL_METADATA
399 * Returns a LTTng metadata file descriptor
401 * The returned channel will be deleted when its file descriptor is closed.
404 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
406 struct lttng_session
*session
= file
->private_data
;
409 case LTTNG_KERNEL_OLD_CHANNEL
:
411 struct lttng_kernel_channel chan_param
;
412 struct lttng_kernel_old_channel old_chan_param
;
414 if (copy_from_user(&old_chan_param
,
415 (struct lttng_kernel_old_channel __user
*) arg
,
416 sizeof(struct lttng_kernel_old_channel
)))
418 chan_param
.overwrite
= old_chan_param
.overwrite
;
419 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
420 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
421 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
422 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
423 chan_param
.output
= old_chan_param
.output
;
425 return lttng_abi_create_channel(file
, &chan_param
,
428 case LTTNG_KERNEL_CHANNEL
:
430 struct lttng_kernel_channel chan_param
;
432 if (copy_from_user(&chan_param
,
433 (struct lttng_kernel_channel __user
*) arg
,
434 sizeof(struct lttng_kernel_channel
)))
436 return lttng_abi_create_channel(file
, &chan_param
,
439 case LTTNG_KERNEL_OLD_SESSION_START
:
440 case LTTNG_KERNEL_OLD_ENABLE
:
441 case LTTNG_KERNEL_SESSION_START
:
442 case LTTNG_KERNEL_ENABLE
:
443 return lttng_session_enable(session
);
444 case LTTNG_KERNEL_OLD_SESSION_STOP
:
445 case LTTNG_KERNEL_OLD_DISABLE
:
446 case LTTNG_KERNEL_SESSION_STOP
:
447 case LTTNG_KERNEL_DISABLE
:
448 return lttng_session_disable(session
);
449 case LTTNG_KERNEL_OLD_METADATA
:
451 struct lttng_kernel_channel chan_param
;
452 struct lttng_kernel_old_channel old_chan_param
;
454 if (copy_from_user(&old_chan_param
,
455 (struct lttng_kernel_old_channel __user
*) arg
,
456 sizeof(struct lttng_kernel_old_channel
)))
458 chan_param
.overwrite
= old_chan_param
.overwrite
;
459 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
460 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
461 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
462 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
463 chan_param
.output
= old_chan_param
.output
;
465 return lttng_abi_create_channel(file
, &chan_param
,
468 case LTTNG_KERNEL_METADATA
:
470 struct lttng_kernel_channel chan_param
;
472 if (copy_from_user(&chan_param
,
473 (struct lttng_kernel_channel __user
*) arg
,
474 sizeof(struct lttng_kernel_channel
)))
476 return lttng_abi_create_channel(file
, &chan_param
,
485 * Called when the last file reference is dropped.
487 * Big fat note: channels and events are invariant for the whole session after
488 * their creation. So this session destruction also destroys all channel and
489 * event structures specific to this session (they are not destroyed when their
490 * individual file is released).
493 int lttng_session_release(struct inode
*inode
, struct file
*file
)
495 struct lttng_session
*session
= file
->private_data
;
498 lttng_session_destroy(session
);
502 static const struct file_operations lttng_session_fops
= {
503 .owner
= THIS_MODULE
,
504 .release
= lttng_session_release
,
505 .unlocked_ioctl
= lttng_session_ioctl
,
507 .compat_ioctl
= lttng_session_ioctl
,
512 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
516 * Handles the poll operations for the metadata channels.
519 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
522 struct lttng_metadata_stream
*stream
= filp
->private_data
;
523 struct lib_ring_buffer
*buf
= stream
->priv
;
525 unsigned int mask
= 0;
527 if (filp
->f_mode
& FMODE_READ
) {
528 poll_wait_set_exclusive(wait
);
529 poll_wait(filp
, &stream
->read_wait
, wait
);
531 finalized
= stream
->finalized
;
534 * lib_ring_buffer_is_finalized() contains a smp_rmb()
535 * ordering finalized load before offsets loads.
537 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
542 if (stream
->metadata_cache
->metadata_written
>
543 stream
->metadata_out
)
551 int lttng_metadata_ring_buffer_ioctl_get_next_subbuf(struct file
*filp
,
552 unsigned int cmd
, unsigned long arg
)
554 struct lttng_metadata_stream
*stream
= filp
->private_data
;
555 struct lib_ring_buffer
*buf
= stream
->priv
;
556 struct channel
*chan
= buf
->backend
.chan
;
559 ret
= lttng_metadata_output_channel(stream
, chan
);
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 * This is not used by anonymous file descriptors. This code is left
676 * there if we ever want to implement an inode with open() operation.
679 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
681 struct lttng_metadata_stream
*stream
= inode
->i_private
;
682 struct lib_ring_buffer
*buf
= stream
->priv
;
684 file
->private_data
= buf
;
686 * Since life-time of metadata cache differs from that of
687 * session, we need to keep our own reference on the transport.
689 if (!try_module_get(stream
->transport
->owner
)) {
690 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
693 return lib_ring_buffer_open(inode
, file
, buf
);
697 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
699 struct lttng_metadata_stream
*stream
= file
->private_data
;
700 struct lib_ring_buffer
*buf
= stream
->priv
;
702 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
703 module_put(stream
->transport
->owner
);
704 return lib_ring_buffer_release(inode
, file
, buf
);
708 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
709 struct pipe_inode_info
*pipe
, size_t len
,
712 struct lttng_metadata_stream
*stream
= in
->private_data
;
713 struct lib_ring_buffer
*buf
= stream
->priv
;
715 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
720 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
721 struct vm_area_struct
*vma
)
723 struct lttng_metadata_stream
*stream
= filp
->private_data
;
724 struct lib_ring_buffer
*buf
= stream
->priv
;
726 return lib_ring_buffer_mmap(filp
, vma
, buf
);
730 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
731 .owner
= THIS_MODULE
,
732 .open
= lttng_metadata_ring_buffer_open
,
733 .release
= lttng_metadata_ring_buffer_release
,
734 .poll
= lttng_metadata_ring_buffer_poll
,
735 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
736 .mmap
= lttng_metadata_ring_buffer_mmap
,
737 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
738 .llseek
= vfs_lib_ring_buffer_no_llseek
,
740 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
745 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
746 const struct file_operations
*fops
)
749 struct file
*stream_file
;
751 stream_fd
= get_unused_fd();
756 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
757 stream_priv
, O_RDWR
);
758 if (IS_ERR(stream_file
)) {
759 ret
= PTR_ERR(stream_file
);
763 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
764 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
765 * file descriptor, so we set FMODE_PREAD here.
767 stream_file
->f_mode
|= FMODE_PREAD
;
768 fd_install(stream_fd
, stream_file
);
770 * The stream holds a reference to the channel within the generic ring
771 * buffer library, so no need to hold a refcount on the channel and
772 * session files here.
777 put_unused_fd(stream_fd
);
783 int lttng_abi_open_stream(struct file
*channel_file
)
785 struct lttng_channel
*channel
= channel_file
->private_data
;
786 struct lib_ring_buffer
*buf
;
790 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
795 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
796 &lib_ring_buffer_file_operations
);
803 channel
->ops
->buffer_read_close(buf
);
808 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
810 struct lttng_channel
*channel
= channel_file
->private_data
;
811 struct lttng_session
*session
= channel
->session
;
812 struct lib_ring_buffer
*buf
;
814 struct lttng_metadata_stream
*metadata_stream
;
817 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
821 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
823 if (!metadata_stream
) {
827 metadata_stream
->metadata_cache
= session
->metadata_cache
;
828 init_waitqueue_head(&metadata_stream
->read_wait
);
829 metadata_stream
->priv
= buf
;
830 stream_priv
= metadata_stream
;
831 metadata_stream
->transport
= channel
->transport
;
834 * Since life-time of metadata cache differs from that of
835 * session, we need to keep our own reference on the transport.
837 if (!try_module_get(metadata_stream
->transport
->owner
)) {
838 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
843 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
844 <tng_metadata_ring_buffer_file_operations
);
848 kref_get(&session
->metadata_cache
->refcount
);
849 list_add(&metadata_stream
->list
,
850 &session
->metadata_cache
->metadata_stream
);
854 module_put(metadata_stream
->transport
->owner
);
856 kfree(metadata_stream
);
858 channel
->ops
->buffer_read_close(buf
);
863 int lttng_abi_create_event(struct file
*channel_file
,
864 struct lttng_kernel_event
*event_param
)
866 struct lttng_channel
*channel
= channel_file
->private_data
;
867 struct lttng_event
*event
;
869 struct file
*event_file
;
871 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
872 switch (event_param
->instrumentation
) {
873 case LTTNG_KERNEL_KRETPROBE
:
874 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
876 case LTTNG_KERNEL_KPROBE
:
877 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
879 case LTTNG_KERNEL_FUNCTION
:
880 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
885 switch (event_param
->instrumentation
) {
887 event_fd
= get_unused_fd();
892 event_file
= anon_inode_getfile("[lttng_event]",
895 if (IS_ERR(event_file
)) {
896 ret
= PTR_ERR(event_file
);
900 * We tolerate no failure path after event creation. It
901 * will stay invariant for the rest of the session.
903 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
904 WARN_ON_ONCE(!event
);
906 ret
= PTR_ERR(event
);
909 event_file
->private_data
= event
;
910 fd_install(event_fd
, event_file
);
911 /* The event holds a reference on the channel */
912 atomic_long_inc(&channel_file
->f_count
);
914 case LTTNG_KERNEL_SYSCALL
:
916 * Only all-syscall tracing supported for now.
918 if (event_param
->name
[0] != '\0')
920 ret
= lttng_syscalls_register(channel
, NULL
);
931 put_unused_fd(event_fd
);
937 * lttng_channel_ioctl - lttng syscall through ioctl
943 * This ioctl implements lttng commands:
944 * LTTNG_KERNEL_STREAM
945 * Returns an event stream file descriptor or failure.
946 * (typically, one event stream records events from one CPU)
948 * Returns an event file descriptor or failure.
949 * LTTNG_KERNEL_CONTEXT
950 * Prepend a context field to each event in the channel
951 * LTTNG_KERNEL_ENABLE
952 * Enable recording for events in this channel (weak enable)
953 * LTTNG_KERNEL_DISABLE
954 * Disable recording for events in this channel (strong disable)
956 * Channel and event file descriptors also hold a reference on the session.
959 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
961 struct lttng_channel
*channel
= file
->private_data
;
964 case LTTNG_KERNEL_OLD_STREAM
:
965 case LTTNG_KERNEL_STREAM
:
966 return lttng_abi_open_stream(file
);
967 case LTTNG_KERNEL_OLD_EVENT
:
969 struct lttng_kernel_event
*uevent_param
;
970 struct lttng_kernel_old_event
*old_uevent_param
;
973 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
979 old_uevent_param
= kmalloc(
980 sizeof(struct lttng_kernel_old_event
),
982 if (!old_uevent_param
) {
984 goto old_event_error_free_param
;
986 if (copy_from_user(old_uevent_param
,
987 (struct lttng_kernel_old_event __user
*) arg
,
988 sizeof(struct lttng_kernel_old_event
))) {
990 goto old_event_error_free_old_param
;
993 memcpy(uevent_param
->name
, old_uevent_param
->name
,
994 sizeof(uevent_param
->name
));
995 uevent_param
->instrumentation
=
996 old_uevent_param
->instrumentation
;
998 switch (old_uevent_param
->instrumentation
) {
999 case LTTNG_KERNEL_KPROBE
:
1000 uevent_param
->u
.kprobe
.addr
=
1001 old_uevent_param
->u
.kprobe
.addr
;
1002 uevent_param
->u
.kprobe
.offset
=
1003 old_uevent_param
->u
.kprobe
.offset
;
1004 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1005 old_uevent_param
->u
.kprobe
.symbol_name
,
1006 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1008 case LTTNG_KERNEL_KRETPROBE
:
1009 uevent_param
->u
.kretprobe
.addr
=
1010 old_uevent_param
->u
.kretprobe
.addr
;
1011 uevent_param
->u
.kretprobe
.offset
=
1012 old_uevent_param
->u
.kretprobe
.offset
;
1013 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1014 old_uevent_param
->u
.kretprobe
.symbol_name
,
1015 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1017 case LTTNG_KERNEL_FUNCTION
:
1018 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1019 old_uevent_param
->u
.ftrace
.symbol_name
,
1020 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1025 ret
= lttng_abi_create_event(file
, uevent_param
);
1027 old_event_error_free_old_param
:
1028 kfree(old_uevent_param
);
1029 old_event_error_free_param
:
1030 kfree(uevent_param
);
1034 case LTTNG_KERNEL_EVENT
:
1036 struct lttng_kernel_event uevent_param
;
1038 if (copy_from_user(&uevent_param
,
1039 (struct lttng_kernel_event __user
*) arg
,
1040 sizeof(uevent_param
)))
1042 return lttng_abi_create_event(file
, &uevent_param
);
1044 case LTTNG_KERNEL_OLD_CONTEXT
:
1046 struct lttng_kernel_context
*ucontext_param
;
1047 struct lttng_kernel_old_context
*old_ucontext_param
;
1050 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1052 if (!ucontext_param
) {
1056 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1058 if (!old_ucontext_param
) {
1060 goto old_ctx_error_free_param
;
1063 if (copy_from_user(old_ucontext_param
,
1064 (struct lttng_kernel_old_context __user
*) arg
,
1065 sizeof(struct lttng_kernel_old_context
))) {
1067 goto old_ctx_error_free_old_param
;
1069 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1070 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1071 sizeof(ucontext_param
->padding
));
1072 /* only type that uses the union */
1073 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1074 ucontext_param
->u
.perf_counter
.type
=
1075 old_ucontext_param
->u
.perf_counter
.type
;
1076 ucontext_param
->u
.perf_counter
.config
=
1077 old_ucontext_param
->u
.perf_counter
.config
;
1078 memcpy(ucontext_param
->u
.perf_counter
.name
,
1079 old_ucontext_param
->u
.perf_counter
.name
,
1080 sizeof(ucontext_param
->u
.perf_counter
.name
));
1083 ret
= lttng_abi_add_context(file
,
1085 &channel
->ctx
, channel
->session
);
1087 old_ctx_error_free_old_param
:
1088 kfree(old_ucontext_param
);
1089 old_ctx_error_free_param
:
1090 kfree(ucontext_param
);
1094 case LTTNG_KERNEL_CONTEXT
:
1096 struct lttng_kernel_context ucontext_param
;
1098 if (copy_from_user(&ucontext_param
,
1099 (struct lttng_kernel_context __user
*) arg
,
1100 sizeof(ucontext_param
)))
1102 return lttng_abi_add_context(file
,
1104 &channel
->ctx
, channel
->session
);
1106 case LTTNG_KERNEL_OLD_ENABLE
:
1107 case LTTNG_KERNEL_ENABLE
:
1108 return lttng_channel_enable(channel
);
1109 case LTTNG_KERNEL_OLD_DISABLE
:
1110 case LTTNG_KERNEL_DISABLE
:
1111 return lttng_channel_disable(channel
);
1113 return -ENOIOCTLCMD
;
1119 * lttng_metadata_ioctl - lttng syscall through ioctl
1125 * This ioctl implements lttng commands:
1126 * LTTNG_KERNEL_STREAM
1127 * Returns an event stream file descriptor or failure.
1129 * Channel and event file descriptors also hold a reference on the session.
1132 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1135 case LTTNG_KERNEL_OLD_STREAM
:
1136 case LTTNG_KERNEL_STREAM
:
1137 return lttng_abi_open_metadata_stream(file
);
1139 return -ENOIOCTLCMD
;
1144 * lttng_channel_poll - lttng stream addition/removal monitoring
1149 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1151 struct lttng_channel
*channel
= file
->private_data
;
1152 unsigned int mask
= 0;
1154 if (file
->f_mode
& FMODE_READ
) {
1155 poll_wait_set_exclusive(wait
);
1156 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1159 if (channel
->ops
->is_disabled(channel
->chan
))
1161 if (channel
->ops
->is_finalized(channel
->chan
))
1163 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1164 return POLLIN
| POLLRDNORM
;
1172 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1174 struct lttng_channel
*channel
= file
->private_data
;
1177 fput(channel
->session
->file
);
1182 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1184 struct lttng_channel
*channel
= file
->private_data
;
1187 lttng_metadata_channel_destroy(channel
);
1188 fput(channel
->session
->file
);
1194 static const struct file_operations lttng_channel_fops
= {
1195 .owner
= THIS_MODULE
,
1196 .release
= lttng_channel_release
,
1197 .poll
= lttng_channel_poll
,
1198 .unlocked_ioctl
= lttng_channel_ioctl
,
1199 #ifdef CONFIG_COMPAT
1200 .compat_ioctl
= lttng_channel_ioctl
,
1204 static const struct file_operations lttng_metadata_fops
= {
1205 .owner
= THIS_MODULE
,
1206 .release
= lttng_metadata_channel_release
,
1207 .unlocked_ioctl
= lttng_metadata_ioctl
,
1208 #ifdef CONFIG_COMPAT
1209 .compat_ioctl
= lttng_metadata_ioctl
,
1214 * lttng_event_ioctl - lttng syscall through ioctl
1220 * This ioctl implements lttng commands:
1221 * LTTNG_KERNEL_CONTEXT
1222 * Prepend a context field to each record of this event
1223 * LTTNG_KERNEL_ENABLE
1224 * Enable recording for this event (weak enable)
1225 * LTTNG_KERNEL_DISABLE
1226 * Disable recording for this event (strong disable)
1229 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1231 struct lttng_event
*event
= file
->private_data
;
1234 case LTTNG_KERNEL_OLD_CONTEXT
:
1236 struct lttng_kernel_context
*ucontext_param
;
1237 struct lttng_kernel_old_context
*old_ucontext_param
;
1240 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1242 if (!ucontext_param
) {
1246 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1248 if (!old_ucontext_param
) {
1250 goto old_ctx_error_free_param
;
1253 if (copy_from_user(old_ucontext_param
,
1254 (struct lttng_kernel_old_context __user
*) arg
,
1255 sizeof(struct lttng_kernel_old_context
))) {
1257 goto old_ctx_error_free_old_param
;
1259 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1260 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1261 sizeof(ucontext_param
->padding
));
1262 /* only type that uses the union */
1263 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1264 ucontext_param
->u
.perf_counter
.type
=
1265 old_ucontext_param
->u
.perf_counter
.type
;
1266 ucontext_param
->u
.perf_counter
.config
=
1267 old_ucontext_param
->u
.perf_counter
.config
;
1268 memcpy(ucontext_param
->u
.perf_counter
.name
,
1269 old_ucontext_param
->u
.perf_counter
.name
,
1270 sizeof(ucontext_param
->u
.perf_counter
.name
));
1273 ret
= lttng_abi_add_context(file
,
1275 &event
->ctx
, event
->chan
->session
);
1277 old_ctx_error_free_old_param
:
1278 kfree(old_ucontext_param
);
1279 old_ctx_error_free_param
:
1280 kfree(ucontext_param
);
1284 case LTTNG_KERNEL_CONTEXT
:
1286 struct lttng_kernel_context ucontext_param
;
1288 if (copy_from_user(&ucontext_param
,
1289 (struct lttng_kernel_context __user
*) arg
,
1290 sizeof(ucontext_param
)))
1292 return lttng_abi_add_context(file
,
1294 &event
->ctx
, event
->chan
->session
);
1296 case LTTNG_KERNEL_OLD_ENABLE
:
1297 case LTTNG_KERNEL_ENABLE
:
1298 return lttng_event_enable(event
);
1299 case LTTNG_KERNEL_OLD_DISABLE
:
1300 case LTTNG_KERNEL_DISABLE
:
1301 return lttng_event_disable(event
);
1303 return -ENOIOCTLCMD
;
1308 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1310 struct lttng_event
*event
= file
->private_data
;
1313 fput(event
->chan
->file
);
1317 /* TODO: filter control ioctl */
1318 static const struct file_operations lttng_event_fops
= {
1319 .owner
= THIS_MODULE
,
1320 .release
= lttng_event_release
,
1321 .unlocked_ioctl
= lttng_event_ioctl
,
1322 #ifdef CONFIG_COMPAT
1323 .compat_ioctl
= lttng_event_ioctl
,
1327 int __init
lttng_abi_init(void)
1331 wrapper_vmalloc_sync_all();
1332 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1335 if (!lttng_proc_dentry
) {
1336 printk(KERN_ERR
"Error creating LTTng control file\n");
1344 void __exit
lttng_abi_exit(void)
1346 if (lttng_proc_dentry
)
1347 remove_proc_entry("lttng", NULL
);