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"
56 #include "lib/ringbuffer/frontend_types.h"
59 * This is LTTng's own personal way to create a system call as an external
60 * module. We use ioctl() on /proc/lttng.
63 static struct proc_dir_entry
*lttng_proc_dentry
;
64 static const struct file_operations lttng_fops
;
65 static const struct file_operations lttng_session_fops
;
66 static const struct file_operations lttng_channel_fops
;
67 static const struct file_operations lttng_metadata_fops
;
68 static const struct file_operations lttng_event_fops
;
69 static struct file_operations lttng_stream_ring_buffer_file_operations
;
72 * Teardown management: opened file descriptors keep a refcount on the module,
73 * so it can only exit when all file descriptors are closed.
77 int lttng_abi_create_session(void)
79 struct lttng_session
*session
;
80 struct file
*session_file
;
83 session
= lttng_session_create();
86 session_fd
= get_unused_fd();
91 session_file
= anon_inode_getfile("[lttng_session]",
94 if (IS_ERR(session_file
)) {
95 ret
= PTR_ERR(session_file
);
98 session
->file
= session_file
;
99 fd_install(session_fd
, session_file
);
103 put_unused_fd(session_fd
);
105 lttng_session_destroy(session
);
110 int lttng_abi_tracepoint_list(void)
112 struct file
*tracepoint_list_file
;
115 file_fd
= get_unused_fd();
121 tracepoint_list_file
= anon_inode_getfile("[lttng_session]",
122 <tng_tracepoint_list_fops
,
124 if (IS_ERR(tracepoint_list_file
)) {
125 ret
= PTR_ERR(tracepoint_list_file
);
128 ret
= lttng_tracepoint_list_fops
.open(NULL
, tracepoint_list_file
);
131 fd_install(file_fd
, tracepoint_list_file
);
139 fput(tracepoint_list_file
);
141 put_unused_fd(file_fd
);
147 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version
*v
)
149 v
->major
= LTTNG_MODULES_MAJOR_VERSION
;
150 v
->minor
= LTTNG_MODULES_MINOR_VERSION
;
151 v
->patchlevel
= LTTNG_MODULES_PATCHLEVEL_VERSION
;
155 long lttng_abi_add_context(struct file
*file
,
156 struct lttng_kernel_context
*context_param
,
157 struct lttng_ctx
**ctx
, struct lttng_session
*session
)
160 if (session
->been_active
)
163 switch (context_param
->ctx
) {
164 case LTTNG_KERNEL_CONTEXT_PID
:
165 return lttng_add_pid_to_ctx(ctx
);
166 case LTTNG_KERNEL_CONTEXT_PRIO
:
167 return lttng_add_prio_to_ctx(ctx
);
168 case LTTNG_KERNEL_CONTEXT_NICE
:
169 return lttng_add_nice_to_ctx(ctx
);
170 case LTTNG_KERNEL_CONTEXT_VPID
:
171 return lttng_add_vpid_to_ctx(ctx
);
172 case LTTNG_KERNEL_CONTEXT_TID
:
173 return lttng_add_tid_to_ctx(ctx
);
174 case LTTNG_KERNEL_CONTEXT_VTID
:
175 return lttng_add_vtid_to_ctx(ctx
);
176 case LTTNG_KERNEL_CONTEXT_PPID
:
177 return lttng_add_ppid_to_ctx(ctx
);
178 case LTTNG_KERNEL_CONTEXT_VPPID
:
179 return lttng_add_vppid_to_ctx(ctx
);
180 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER
:
181 context_param
->u
.perf_counter
.name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
182 return lttng_add_perf_counter_to_ctx(context_param
->u
.perf_counter
.type
,
183 context_param
->u
.perf_counter
.config
,
184 context_param
->u
.perf_counter
.name
,
186 case LTTNG_KERNEL_CONTEXT_PROCNAME
:
187 return lttng_add_procname_to_ctx(ctx
);
188 case LTTNG_KERNEL_CONTEXT_HOSTNAME
:
189 return lttng_add_hostname_to_ctx(ctx
);
196 * lttng_ioctl - lttng syscall through ioctl
202 * This ioctl implements lttng commands:
203 * LTTNG_KERNEL_SESSION
204 * Returns a LTTng trace session file descriptor
205 * LTTNG_KERNEL_TRACER_VERSION
206 * Returns the LTTng kernel tracer version
207 * LTTNG_KERNEL_TRACEPOINT_LIST
208 * Returns a file descriptor listing available tracepoints
209 * LTTNG_KERNEL_WAIT_QUIESCENT
210 * Returns after all previously running probes have completed
212 * The returned session will be deleted when its file descriptor is closed.
215 long lttng_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
218 case LTTNG_KERNEL_OLD_SESSION
:
219 case LTTNG_KERNEL_SESSION
:
220 return lttng_abi_create_session();
221 case LTTNG_KERNEL_OLD_TRACER_VERSION
:
223 struct lttng_kernel_tracer_version v
;
224 struct lttng_kernel_old_tracer_version oldv
;
225 struct lttng_kernel_old_tracer_version
*uversion
=
226 (struct lttng_kernel_old_tracer_version __user
*) arg
;
228 lttng_abi_tracer_version(&v
);
229 oldv
.major
= v
.major
;
230 oldv
.minor
= v
.minor
;
231 oldv
.patchlevel
= v
.patchlevel
;
233 if (copy_to_user(uversion
, &oldv
, sizeof(oldv
)))
237 case LTTNG_KERNEL_TRACER_VERSION
:
239 struct lttng_kernel_tracer_version version
;
240 struct lttng_kernel_tracer_version
*uversion
=
241 (struct lttng_kernel_tracer_version __user
*) arg
;
243 lttng_abi_tracer_version(&version
);
245 if (copy_to_user(uversion
, &version
, sizeof(version
)))
249 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST
:
250 case LTTNG_KERNEL_TRACEPOINT_LIST
:
251 return lttng_abi_tracepoint_list();
252 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT
:
253 case LTTNG_KERNEL_WAIT_QUIESCENT
:
256 case LTTNG_KERNEL_OLD_CALIBRATE
:
258 struct lttng_kernel_old_calibrate __user
*ucalibrate
=
259 (struct lttng_kernel_old_calibrate __user
*) arg
;
260 struct lttng_kernel_old_calibrate old_calibrate
;
261 struct lttng_kernel_calibrate calibrate
;
264 if (copy_from_user(&old_calibrate
, ucalibrate
, sizeof(old_calibrate
)))
266 calibrate
.type
= old_calibrate
.type
;
267 ret
= lttng_calibrate(&calibrate
);
268 if (copy_to_user(ucalibrate
, &old_calibrate
, sizeof(old_calibrate
)))
272 case LTTNG_KERNEL_CALIBRATE
:
274 struct lttng_kernel_calibrate __user
*ucalibrate
=
275 (struct lttng_kernel_calibrate __user
*) arg
;
276 struct lttng_kernel_calibrate calibrate
;
279 if (copy_from_user(&calibrate
, ucalibrate
, sizeof(calibrate
)))
281 ret
= lttng_calibrate(&calibrate
);
282 if (copy_to_user(ucalibrate
, &calibrate
, sizeof(calibrate
)))
291 static const struct file_operations lttng_fops
= {
292 .owner
= THIS_MODULE
,
293 .unlocked_ioctl
= lttng_ioctl
,
295 .compat_ioctl
= lttng_ioctl
,
300 int lttng_abi_create_channel(struct file
*session_file
,
301 struct lttng_kernel_channel
*chan_param
,
302 enum channel_type channel_type
)
304 struct lttng_session
*session
= session_file
->private_data
;
305 const struct file_operations
*fops
= NULL
;
306 const char *transport_name
;
307 struct lttng_channel
*chan
;
308 struct file
*chan_file
;
312 chan_fd
= get_unused_fd();
317 switch (channel_type
) {
318 case PER_CPU_CHANNEL
:
319 fops
= <tng_channel_fops
;
321 case METADATA_CHANNEL
:
322 fops
= <tng_metadata_fops
;
326 chan_file
= anon_inode_getfile("[lttng_channel]",
329 if (IS_ERR(chan_file
)) {
330 ret
= PTR_ERR(chan_file
);
333 switch (channel_type
) {
334 case PER_CPU_CHANNEL
:
335 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
) {
336 transport_name
= chan_param
->overwrite
?
337 "relay-overwrite" : "relay-discard";
338 } else if (chan_param
->output
== LTTNG_KERNEL_MMAP
) {
339 transport_name
= chan_param
->overwrite
?
340 "relay-overwrite-mmap" : "relay-discard-mmap";
345 case METADATA_CHANNEL
:
346 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
)
347 transport_name
= "relay-metadata";
348 else if (chan_param
->output
== LTTNG_KERNEL_MMAP
)
349 transport_name
= "relay-metadata-mmap";
354 transport_name
= "<unknown>";
358 * We tolerate no failure path after channel creation. It will stay
359 * invariant for the rest of the session.
361 chan
= lttng_channel_create(session
, transport_name
, NULL
,
362 chan_param
->subbuf_size
,
363 chan_param
->num_subbuf
,
364 chan_param
->switch_timer_interval
,
365 chan_param
->read_timer_interval
,
371 chan
->file
= chan_file
;
372 chan_file
->private_data
= chan
;
373 fd_install(chan_fd
, chan_file
);
374 atomic_long_inc(&session_file
->f_count
);
381 put_unused_fd(chan_fd
);
387 * lttng_session_ioctl - lttng session fd ioctl
393 * This ioctl implements lttng commands:
394 * LTTNG_KERNEL_CHANNEL
395 * Returns a LTTng channel file descriptor
396 * LTTNG_KERNEL_ENABLE
397 * Enables tracing for a session (weak enable)
398 * LTTNG_KERNEL_DISABLE
399 * Disables tracing for a session (strong disable)
400 * LTTNG_KERNEL_METADATA
401 * Returns a LTTng metadata file descriptor
403 * The returned channel will be deleted when its file descriptor is closed.
406 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
408 struct lttng_session
*session
= file
->private_data
;
411 case LTTNG_KERNEL_OLD_CHANNEL
:
413 struct lttng_kernel_channel chan_param
;
414 struct lttng_kernel_old_channel old_chan_param
;
416 if (copy_from_user(&old_chan_param
,
417 (struct lttng_kernel_old_channel __user
*) arg
,
418 sizeof(struct lttng_kernel_old_channel
)))
420 chan_param
.overwrite
= old_chan_param
.overwrite
;
421 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
422 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
423 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
424 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
425 chan_param
.output
= old_chan_param
.output
;
427 return lttng_abi_create_channel(file
, &chan_param
,
430 case LTTNG_KERNEL_CHANNEL
:
432 struct lttng_kernel_channel chan_param
;
434 if (copy_from_user(&chan_param
,
435 (struct lttng_kernel_channel __user
*) arg
,
436 sizeof(struct lttng_kernel_channel
)))
438 return lttng_abi_create_channel(file
, &chan_param
,
441 case LTTNG_KERNEL_OLD_SESSION_START
:
442 case LTTNG_KERNEL_OLD_ENABLE
:
443 case LTTNG_KERNEL_SESSION_START
:
444 case LTTNG_KERNEL_ENABLE
:
445 return lttng_session_enable(session
);
446 case LTTNG_KERNEL_OLD_SESSION_STOP
:
447 case LTTNG_KERNEL_OLD_DISABLE
:
448 case LTTNG_KERNEL_SESSION_STOP
:
449 case LTTNG_KERNEL_DISABLE
:
450 return lttng_session_disable(session
);
451 case LTTNG_KERNEL_OLD_METADATA
:
453 struct lttng_kernel_channel chan_param
;
454 struct lttng_kernel_old_channel old_chan_param
;
456 if (copy_from_user(&old_chan_param
,
457 (struct lttng_kernel_old_channel __user
*) arg
,
458 sizeof(struct lttng_kernel_old_channel
)))
460 chan_param
.overwrite
= old_chan_param
.overwrite
;
461 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
462 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
463 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
464 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
465 chan_param
.output
= old_chan_param
.output
;
467 return lttng_abi_create_channel(file
, &chan_param
,
470 case LTTNG_KERNEL_METADATA
:
472 struct lttng_kernel_channel chan_param
;
474 if (copy_from_user(&chan_param
,
475 (struct lttng_kernel_channel __user
*) arg
,
476 sizeof(struct lttng_kernel_channel
)))
478 return lttng_abi_create_channel(file
, &chan_param
,
487 * Called when the last file reference is dropped.
489 * Big fat note: channels and events are invariant for the whole session after
490 * their creation. So this session destruction also destroys all channel and
491 * event structures specific to this session (they are not destroyed when their
492 * individual file is released).
495 int lttng_session_release(struct inode
*inode
, struct file
*file
)
497 struct lttng_session
*session
= file
->private_data
;
500 lttng_session_destroy(session
);
504 static const struct file_operations lttng_session_fops
= {
505 .owner
= THIS_MODULE
,
506 .release
= lttng_session_release
,
507 .unlocked_ioctl
= lttng_session_ioctl
,
509 .compat_ioctl
= lttng_session_ioctl
,
514 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
518 * Handles the poll operations for the metadata channels.
521 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
524 struct lttng_metadata_stream
*stream
= filp
->private_data
;
525 struct lib_ring_buffer
*buf
= stream
->priv
;
527 unsigned int mask
= 0;
529 if (filp
->f_mode
& FMODE_READ
) {
530 poll_wait_set_exclusive(wait
);
531 poll_wait(filp
, &stream
->read_wait
, wait
);
533 finalized
= stream
->finalized
;
536 * lib_ring_buffer_is_finalized() contains a smp_rmb()
537 * ordering finalized load before offsets loads.
539 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
544 if (stream
->metadata_cache
->metadata_written
>
545 stream
->metadata_out
)
553 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
554 unsigned int cmd
, unsigned long arg
)
556 struct lttng_metadata_stream
*stream
= filp
->private_data
;
558 stream
->metadata_out
= stream
->metadata_in
;
562 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
563 unsigned int cmd
, unsigned long arg
)
566 struct lttng_metadata_stream
*stream
= filp
->private_data
;
567 struct lib_ring_buffer
*buf
= stream
->priv
;
570 case RING_BUFFER_GET_NEXT_SUBBUF
:
572 struct lttng_metadata_stream
*stream
= filp
->private_data
;
573 struct lib_ring_buffer
*buf
= stream
->priv
;
574 struct channel
*chan
= buf
->backend
.chan
;
576 ret
= lttng_metadata_output_channel(stream
, chan
);
578 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
584 case RING_BUFFER_GET_SUBBUF
:
587 * Random access is not allowed for metadata channel.
591 case RING_BUFFER_FLUSH
:
593 struct lttng_metadata_stream
*stream
= filp
->private_data
;
594 struct lib_ring_buffer
*buf
= stream
->priv
;
595 struct channel
*chan
= buf
->backend
.chan
;
598 * Before doing the actual ring buffer flush, write up to one
599 * packet of metadata in the ring buffer.
601 ret
= lttng_metadata_output_channel(stream
, chan
);
609 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
611 /* Performing lib ring buffer ioctl after our own. */
612 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
617 case RING_BUFFER_PUT_NEXT_SUBBUF
:
619 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
632 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
633 unsigned int cmd
, unsigned long arg
)
636 struct lttng_metadata_stream
*stream
= filp
->private_data
;
637 struct lib_ring_buffer
*buf
= stream
->priv
;
640 case RING_BUFFER_GET_NEXT_SUBBUF
:
642 struct lttng_metadata_stream
*stream
= filp
->private_data
;
643 struct lib_ring_buffer
*buf
= stream
->priv
;
644 struct channel
*chan
= buf
->backend
.chan
;
646 ret
= lttng_metadata_output_channel(stream
, chan
);
648 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
654 case RING_BUFFER_GET_SUBBUF
:
657 * Random access is not allowed for metadata channel.
664 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
666 /* Performing lib ring buffer ioctl after our own. */
667 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
672 case RING_BUFFER_PUT_NEXT_SUBBUF
:
674 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
687 * This is not used by anonymous file descriptors. This code is left
688 * there if we ever want to implement an inode with open() operation.
691 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
693 struct lttng_metadata_stream
*stream
= inode
->i_private
;
694 struct lib_ring_buffer
*buf
= stream
->priv
;
696 file
->private_data
= buf
;
698 * Since life-time of metadata cache differs from that of
699 * session, we need to keep our own reference on the transport.
701 if (!try_module_get(stream
->transport
->owner
)) {
702 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
705 return lib_ring_buffer_open(inode
, file
, buf
);
709 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
711 struct lttng_metadata_stream
*stream
= file
->private_data
;
712 struct lib_ring_buffer
*buf
= stream
->priv
;
714 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
715 module_put(stream
->transport
->owner
);
716 return lib_ring_buffer_release(inode
, file
, buf
);
720 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
721 struct pipe_inode_info
*pipe
, size_t len
,
724 struct lttng_metadata_stream
*stream
= in
->private_data
;
725 struct lib_ring_buffer
*buf
= stream
->priv
;
727 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
732 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
733 struct vm_area_struct
*vma
)
735 struct lttng_metadata_stream
*stream
= filp
->private_data
;
736 struct lib_ring_buffer
*buf
= stream
->priv
;
738 return lib_ring_buffer_mmap(filp
, vma
, buf
);
742 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
743 .owner
= THIS_MODULE
,
744 .open
= lttng_metadata_ring_buffer_open
,
745 .release
= lttng_metadata_ring_buffer_release
,
746 .poll
= lttng_metadata_ring_buffer_poll
,
747 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
748 .mmap
= lttng_metadata_ring_buffer_mmap
,
749 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
750 .llseek
= vfs_lib_ring_buffer_no_llseek
,
752 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
757 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
758 const struct file_operations
*fops
)
761 struct file
*stream_file
;
763 stream_fd
= get_unused_fd();
768 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
769 stream_priv
, O_RDWR
);
770 if (IS_ERR(stream_file
)) {
771 ret
= PTR_ERR(stream_file
);
775 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
776 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
777 * file descriptor, so we set FMODE_PREAD here.
779 stream_file
->f_mode
|= FMODE_PREAD
;
780 fd_install(stream_fd
, stream_file
);
782 * The stream holds a reference to the channel within the generic ring
783 * buffer library, so no need to hold a refcount on the channel and
784 * session files here.
789 put_unused_fd(stream_fd
);
795 int lttng_abi_open_stream(struct file
*channel_file
)
797 struct lttng_channel
*channel
= channel_file
->private_data
;
798 struct lib_ring_buffer
*buf
;
802 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
807 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
808 <tng_stream_ring_buffer_file_operations
);
815 channel
->ops
->buffer_read_close(buf
);
820 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
822 struct lttng_channel
*channel
= channel_file
->private_data
;
823 struct lttng_session
*session
= channel
->session
;
824 struct lib_ring_buffer
*buf
;
826 struct lttng_metadata_stream
*metadata_stream
;
829 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
833 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
835 if (!metadata_stream
) {
839 metadata_stream
->metadata_cache
= session
->metadata_cache
;
840 init_waitqueue_head(&metadata_stream
->read_wait
);
841 metadata_stream
->priv
= buf
;
842 stream_priv
= metadata_stream
;
843 metadata_stream
->transport
= channel
->transport
;
846 * Since life-time of metadata cache differs from that of
847 * session, we need to keep our own reference on the transport.
849 if (!try_module_get(metadata_stream
->transport
->owner
)) {
850 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
855 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
856 <tng_metadata_ring_buffer_file_operations
);
860 kref_get(&session
->metadata_cache
->refcount
);
861 list_add(&metadata_stream
->list
,
862 &session
->metadata_cache
->metadata_stream
);
866 module_put(metadata_stream
->transport
->owner
);
868 kfree(metadata_stream
);
870 channel
->ops
->buffer_read_close(buf
);
875 int lttng_abi_create_event(struct file
*channel_file
,
876 struct lttng_kernel_event
*event_param
)
878 struct lttng_channel
*channel
= channel_file
->private_data
;
879 struct lttng_event
*event
;
881 struct file
*event_file
;
883 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
884 switch (event_param
->instrumentation
) {
885 case LTTNG_KERNEL_KRETPROBE
:
886 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
888 case LTTNG_KERNEL_KPROBE
:
889 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
891 case LTTNG_KERNEL_FUNCTION
:
892 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
897 switch (event_param
->instrumentation
) {
899 event_fd
= get_unused_fd();
904 event_file
= anon_inode_getfile("[lttng_event]",
907 if (IS_ERR(event_file
)) {
908 ret
= PTR_ERR(event_file
);
912 * We tolerate no failure path after event creation. It
913 * will stay invariant for the rest of the session.
915 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
916 WARN_ON_ONCE(!event
);
918 ret
= PTR_ERR(event
);
921 event_file
->private_data
= event
;
922 fd_install(event_fd
, event_file
);
923 /* The event holds a reference on the channel */
924 atomic_long_inc(&channel_file
->f_count
);
926 case LTTNG_KERNEL_SYSCALL
:
928 * Only all-syscall tracing supported for now.
930 if (event_param
->name
[0] != '\0')
932 ret
= lttng_syscalls_register(channel
, NULL
);
943 put_unused_fd(event_fd
);
949 * lttng_channel_ioctl - lttng syscall through ioctl
955 * This ioctl implements lttng commands:
956 * LTTNG_KERNEL_STREAM
957 * Returns an event stream file descriptor or failure.
958 * (typically, one event stream records events from one CPU)
960 * Returns an event file descriptor or failure.
961 * LTTNG_KERNEL_CONTEXT
962 * Prepend a context field to each event in the channel
963 * LTTNG_KERNEL_ENABLE
964 * Enable recording for events in this channel (weak enable)
965 * LTTNG_KERNEL_DISABLE
966 * Disable recording for events in this channel (strong disable)
968 * Channel and event file descriptors also hold a reference on the session.
971 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
973 struct lttng_channel
*channel
= file
->private_data
;
976 case LTTNG_KERNEL_OLD_STREAM
:
977 case LTTNG_KERNEL_STREAM
:
978 return lttng_abi_open_stream(file
);
979 case LTTNG_KERNEL_OLD_EVENT
:
981 struct lttng_kernel_event
*uevent_param
;
982 struct lttng_kernel_old_event
*old_uevent_param
;
985 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
991 old_uevent_param
= kmalloc(
992 sizeof(struct lttng_kernel_old_event
),
994 if (!old_uevent_param
) {
996 goto old_event_error_free_param
;
998 if (copy_from_user(old_uevent_param
,
999 (struct lttng_kernel_old_event __user
*) arg
,
1000 sizeof(struct lttng_kernel_old_event
))) {
1002 goto old_event_error_free_old_param
;
1005 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1006 sizeof(uevent_param
->name
));
1007 uevent_param
->instrumentation
=
1008 old_uevent_param
->instrumentation
;
1010 switch (old_uevent_param
->instrumentation
) {
1011 case LTTNG_KERNEL_KPROBE
:
1012 uevent_param
->u
.kprobe
.addr
=
1013 old_uevent_param
->u
.kprobe
.addr
;
1014 uevent_param
->u
.kprobe
.offset
=
1015 old_uevent_param
->u
.kprobe
.offset
;
1016 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1017 old_uevent_param
->u
.kprobe
.symbol_name
,
1018 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1020 case LTTNG_KERNEL_KRETPROBE
:
1021 uevent_param
->u
.kretprobe
.addr
=
1022 old_uevent_param
->u
.kretprobe
.addr
;
1023 uevent_param
->u
.kretprobe
.offset
=
1024 old_uevent_param
->u
.kretprobe
.offset
;
1025 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1026 old_uevent_param
->u
.kretprobe
.symbol_name
,
1027 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1029 case LTTNG_KERNEL_FUNCTION
:
1030 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1031 old_uevent_param
->u
.ftrace
.symbol_name
,
1032 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1037 ret
= lttng_abi_create_event(file
, uevent_param
);
1039 old_event_error_free_old_param
:
1040 kfree(old_uevent_param
);
1041 old_event_error_free_param
:
1042 kfree(uevent_param
);
1046 case LTTNG_KERNEL_EVENT
:
1048 struct lttng_kernel_event uevent_param
;
1050 if (copy_from_user(&uevent_param
,
1051 (struct lttng_kernel_event __user
*) arg
,
1052 sizeof(uevent_param
)))
1054 return lttng_abi_create_event(file
, &uevent_param
);
1056 case LTTNG_KERNEL_OLD_CONTEXT
:
1058 struct lttng_kernel_context
*ucontext_param
;
1059 struct lttng_kernel_old_context
*old_ucontext_param
;
1062 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1064 if (!ucontext_param
) {
1068 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1070 if (!old_ucontext_param
) {
1072 goto old_ctx_error_free_param
;
1075 if (copy_from_user(old_ucontext_param
,
1076 (struct lttng_kernel_old_context __user
*) arg
,
1077 sizeof(struct lttng_kernel_old_context
))) {
1079 goto old_ctx_error_free_old_param
;
1081 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1082 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1083 sizeof(ucontext_param
->padding
));
1084 /* only type that uses the union */
1085 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1086 ucontext_param
->u
.perf_counter
.type
=
1087 old_ucontext_param
->u
.perf_counter
.type
;
1088 ucontext_param
->u
.perf_counter
.config
=
1089 old_ucontext_param
->u
.perf_counter
.config
;
1090 memcpy(ucontext_param
->u
.perf_counter
.name
,
1091 old_ucontext_param
->u
.perf_counter
.name
,
1092 sizeof(ucontext_param
->u
.perf_counter
.name
));
1095 ret
= lttng_abi_add_context(file
,
1097 &channel
->ctx
, channel
->session
);
1099 old_ctx_error_free_old_param
:
1100 kfree(old_ucontext_param
);
1101 old_ctx_error_free_param
:
1102 kfree(ucontext_param
);
1106 case LTTNG_KERNEL_CONTEXT
:
1108 struct lttng_kernel_context ucontext_param
;
1110 if (copy_from_user(&ucontext_param
,
1111 (struct lttng_kernel_context __user
*) arg
,
1112 sizeof(ucontext_param
)))
1114 return lttng_abi_add_context(file
,
1116 &channel
->ctx
, channel
->session
);
1118 case LTTNG_KERNEL_OLD_ENABLE
:
1119 case LTTNG_KERNEL_ENABLE
:
1120 return lttng_channel_enable(channel
);
1121 case LTTNG_KERNEL_OLD_DISABLE
:
1122 case LTTNG_KERNEL_DISABLE
:
1123 return lttng_channel_disable(channel
);
1125 return -ENOIOCTLCMD
;
1131 * lttng_metadata_ioctl - lttng syscall through ioctl
1137 * This ioctl implements lttng commands:
1138 * LTTNG_KERNEL_STREAM
1139 * Returns an event stream file descriptor or failure.
1141 * Channel and event file descriptors also hold a reference on the session.
1144 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1147 case LTTNG_KERNEL_OLD_STREAM
:
1148 case LTTNG_KERNEL_STREAM
:
1149 return lttng_abi_open_metadata_stream(file
);
1151 return -ENOIOCTLCMD
;
1156 * lttng_channel_poll - lttng stream addition/removal monitoring
1161 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1163 struct lttng_channel
*channel
= file
->private_data
;
1164 unsigned int mask
= 0;
1166 if (file
->f_mode
& FMODE_READ
) {
1167 poll_wait_set_exclusive(wait
);
1168 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1171 if (channel
->ops
->is_disabled(channel
->chan
))
1173 if (channel
->ops
->is_finalized(channel
->chan
))
1175 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1176 return POLLIN
| POLLRDNORM
;
1184 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1186 struct lttng_channel
*channel
= file
->private_data
;
1189 fput(channel
->session
->file
);
1194 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1196 struct lttng_channel
*channel
= file
->private_data
;
1199 lttng_metadata_channel_destroy(channel
);
1200 fput(channel
->session
->file
);
1206 static const struct file_operations lttng_channel_fops
= {
1207 .owner
= THIS_MODULE
,
1208 .release
= lttng_channel_release
,
1209 .poll
= lttng_channel_poll
,
1210 .unlocked_ioctl
= lttng_channel_ioctl
,
1211 #ifdef CONFIG_COMPAT
1212 .compat_ioctl
= lttng_channel_ioctl
,
1216 static const struct file_operations lttng_metadata_fops
= {
1217 .owner
= THIS_MODULE
,
1218 .release
= lttng_metadata_channel_release
,
1219 .unlocked_ioctl
= lttng_metadata_ioctl
,
1220 #ifdef CONFIG_COMPAT
1221 .compat_ioctl
= lttng_metadata_ioctl
,
1226 * lttng_event_ioctl - lttng syscall through ioctl
1232 * This ioctl implements lttng commands:
1233 * LTTNG_KERNEL_CONTEXT
1234 * Prepend a context field to each record of this event
1235 * LTTNG_KERNEL_ENABLE
1236 * Enable recording for this event (weak enable)
1237 * LTTNG_KERNEL_DISABLE
1238 * Disable recording for this event (strong disable)
1241 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1243 struct lttng_event
*event
= file
->private_data
;
1246 case LTTNG_KERNEL_OLD_CONTEXT
:
1248 struct lttng_kernel_context
*ucontext_param
;
1249 struct lttng_kernel_old_context
*old_ucontext_param
;
1252 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1254 if (!ucontext_param
) {
1258 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1260 if (!old_ucontext_param
) {
1262 goto old_ctx_error_free_param
;
1265 if (copy_from_user(old_ucontext_param
,
1266 (struct lttng_kernel_old_context __user
*) arg
,
1267 sizeof(struct lttng_kernel_old_context
))) {
1269 goto old_ctx_error_free_old_param
;
1271 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1272 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1273 sizeof(ucontext_param
->padding
));
1274 /* only type that uses the union */
1275 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1276 ucontext_param
->u
.perf_counter
.type
=
1277 old_ucontext_param
->u
.perf_counter
.type
;
1278 ucontext_param
->u
.perf_counter
.config
=
1279 old_ucontext_param
->u
.perf_counter
.config
;
1280 memcpy(ucontext_param
->u
.perf_counter
.name
,
1281 old_ucontext_param
->u
.perf_counter
.name
,
1282 sizeof(ucontext_param
->u
.perf_counter
.name
));
1285 ret
= lttng_abi_add_context(file
,
1287 &event
->ctx
, event
->chan
->session
);
1289 old_ctx_error_free_old_param
:
1290 kfree(old_ucontext_param
);
1291 old_ctx_error_free_param
:
1292 kfree(ucontext_param
);
1296 case LTTNG_KERNEL_CONTEXT
:
1298 struct lttng_kernel_context ucontext_param
;
1300 if (copy_from_user(&ucontext_param
,
1301 (struct lttng_kernel_context __user
*) arg
,
1302 sizeof(ucontext_param
)))
1304 return lttng_abi_add_context(file
,
1306 &event
->ctx
, event
->chan
->session
);
1308 case LTTNG_KERNEL_OLD_ENABLE
:
1309 case LTTNG_KERNEL_ENABLE
:
1310 return lttng_event_enable(event
);
1311 case LTTNG_KERNEL_OLD_DISABLE
:
1312 case LTTNG_KERNEL_DISABLE
:
1313 return lttng_event_disable(event
);
1315 return -ENOIOCTLCMD
;
1320 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1322 struct lttng_event
*event
= file
->private_data
;
1325 fput(event
->chan
->file
);
1329 /* TODO: filter control ioctl */
1330 static const struct file_operations lttng_event_fops
= {
1331 .owner
= THIS_MODULE
,
1332 .release
= lttng_event_release
,
1333 .unlocked_ioctl
= lttng_event_ioctl
,
1334 #ifdef CONFIG_COMPAT
1335 .compat_ioctl
= lttng_event_ioctl
,
1339 static int put_u64(uint64_t val
, unsigned long arg
)
1341 return put_user(val
, (uint64_t __user
*) arg
);
1344 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1345 unsigned int cmd
, unsigned long arg
)
1347 struct lib_ring_buffer
*buf
= filp
->private_data
;
1348 struct channel
*chan
= buf
->backend
.chan
;
1349 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1350 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1353 if (atomic_read(&chan
->record_disabled
))
1357 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1361 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1364 return put_u64(ts
, arg
);
1366 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1370 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1373 return put_u64(ts
, arg
);
1375 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1379 ret
= ops
->events_discarded(config
, buf
, &ed
);
1382 return put_u64(ed
, arg
);
1384 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1388 ret
= ops
->content_size(config
, buf
, &cs
);
1391 return put_u64(cs
, arg
);
1393 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1397 ret
= ops
->packet_size(config
, buf
, &ps
);
1400 return put_u64(ps
, arg
);
1402 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1406 ret
= ops
->stream_id(config
, buf
, &si
);
1409 return put_u64(si
, arg
);
1411 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1415 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1418 return put_u64(ts
, arg
);
1421 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1429 #ifdef CONFIG_COMPAT
1430 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1431 unsigned int cmd
, unsigned long arg
)
1433 struct lib_ring_buffer
*buf
= filp
->private_data
;
1434 struct channel
*chan
= buf
->backend
.chan
;
1435 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1436 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1439 if (atomic_read(&chan
->record_disabled
))
1443 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1447 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1450 return put_u64(ts
, arg
);
1452 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1456 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1459 return put_u64(ts
, arg
);
1461 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1465 ret
= ops
->events_discarded(config
, buf
, &ed
);
1468 return put_u64(ed
, arg
);
1470 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1474 ret
= ops
->content_size(config
, buf
, &cs
);
1477 return put_u64(cs
, arg
);
1479 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1483 ret
= ops
->packet_size(config
, buf
, &ps
);
1486 return put_u64(ps
, arg
);
1488 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1492 ret
= ops
->stream_id(config
, buf
, &si
);
1495 return put_u64(si
, arg
);
1497 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1501 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1504 return put_u64(ts
, arg
);
1507 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1514 #endif /* CONFIG_COMPAT */
1516 static void lttng_stream_override_ring_buffer_fops(void)
1518 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1519 lttng_stream_ring_buffer_file_operations
.open
=
1520 lib_ring_buffer_file_operations
.open
;
1521 lttng_stream_ring_buffer_file_operations
.release
=
1522 lib_ring_buffer_file_operations
.release
;
1523 lttng_stream_ring_buffer_file_operations
.poll
=
1524 lib_ring_buffer_file_operations
.poll
;
1525 lttng_stream_ring_buffer_file_operations
.splice_read
=
1526 lib_ring_buffer_file_operations
.splice_read
;
1527 lttng_stream_ring_buffer_file_operations
.mmap
=
1528 lib_ring_buffer_file_operations
.mmap
;
1529 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1530 lttng_stream_ring_buffer_ioctl
;
1531 lttng_stream_ring_buffer_file_operations
.llseek
=
1532 lib_ring_buffer_file_operations
.llseek
;
1533 #ifdef CONFIG_COMPAT
1534 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1535 lttng_stream_ring_buffer_compat_ioctl
;
1539 int __init
lttng_abi_init(void)
1543 wrapper_vmalloc_sync_all();
1544 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1547 if (!lttng_proc_dentry
) {
1548 printk(KERN_ERR
"Error creating LTTng control file\n");
1552 lttng_stream_override_ring_buffer_fops();
1558 /* No __exit annotation because used by init error path too. */
1559 void lttng_abi_exit(void)
1561 if (lttng_proc_dentry
)
1562 remove_proc_entry("lttng", NULL
);