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 "wrapper/file.h"
53 #include "lttng-abi.h"
54 #include "lttng-abi-old.h"
55 #include "lttng-events.h"
56 #include "lttng-tracer.h"
57 #include "lib/ringbuffer/frontend_types.h"
60 * This is LTTng's own personal way to create a system call as an external
61 * module. We use ioctl() on /proc/lttng.
64 static struct proc_dir_entry
*lttng_proc_dentry
;
65 static const struct file_operations lttng_fops
;
66 static const struct file_operations lttng_session_fops
;
67 static const struct file_operations lttng_channel_fops
;
68 static const struct file_operations lttng_metadata_fops
;
69 static const struct file_operations lttng_event_fops
;
70 static struct file_operations lttng_stream_ring_buffer_file_operations
;
73 * Teardown management: opened file descriptors keep a refcount on the module,
74 * so it can only exit when all file descriptors are closed.
78 int lttng_abi_create_session(void)
80 struct lttng_session
*session
;
81 struct file
*session_file
;
84 session
= lttng_session_create();
87 session_fd
= lttng_get_unused_fd();
92 session_file
= anon_inode_getfile("[lttng_session]",
95 if (IS_ERR(session_file
)) {
96 ret
= PTR_ERR(session_file
);
99 session
->file
= session_file
;
100 fd_install(session_fd
, session_file
);
104 put_unused_fd(session_fd
);
106 lttng_session_destroy(session
);
111 int lttng_abi_tracepoint_list(void)
113 struct file
*tracepoint_list_file
;
116 file_fd
= lttng_get_unused_fd();
122 tracepoint_list_file
= anon_inode_getfile("[lttng_tracepoint_list]",
123 <tng_tracepoint_list_fops
,
125 if (IS_ERR(tracepoint_list_file
)) {
126 ret
= PTR_ERR(tracepoint_list_file
);
129 ret
= lttng_tracepoint_list_fops
.open(NULL
, tracepoint_list_file
);
132 fd_install(file_fd
, tracepoint_list_file
);
140 fput(tracepoint_list_file
);
142 put_unused_fd(file_fd
);
148 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version
*v
)
150 v
->major
= LTTNG_MODULES_MAJOR_VERSION
;
151 v
->minor
= LTTNG_MODULES_MINOR_VERSION
;
152 v
->patchlevel
= LTTNG_MODULES_PATCHLEVEL_VERSION
;
156 void lttng_abi_tracer_abi_version(struct lttng_kernel_tracer_abi_version
*v
)
158 v
->major
= LTTNG_MODULES_ABI_MAJOR_VERSION
;
159 v
->minor
= LTTNG_MODULES_ABI_MINOR_VERSION
;
163 long lttng_abi_add_context(struct file
*file
,
164 struct lttng_kernel_context
*context_param
,
165 struct lttng_ctx
**ctx
, struct lttng_session
*session
)
168 if (session
->been_active
)
171 switch (context_param
->ctx
) {
172 case LTTNG_KERNEL_CONTEXT_PID
:
173 return lttng_add_pid_to_ctx(ctx
);
174 case LTTNG_KERNEL_CONTEXT_PRIO
:
175 return lttng_add_prio_to_ctx(ctx
);
176 case LTTNG_KERNEL_CONTEXT_NICE
:
177 return lttng_add_nice_to_ctx(ctx
);
178 case LTTNG_KERNEL_CONTEXT_VPID
:
179 return lttng_add_vpid_to_ctx(ctx
);
180 case LTTNG_KERNEL_CONTEXT_TID
:
181 return lttng_add_tid_to_ctx(ctx
);
182 case LTTNG_KERNEL_CONTEXT_VTID
:
183 return lttng_add_vtid_to_ctx(ctx
);
184 case LTTNG_KERNEL_CONTEXT_PPID
:
185 return lttng_add_ppid_to_ctx(ctx
);
186 case LTTNG_KERNEL_CONTEXT_VPPID
:
187 return lttng_add_vppid_to_ctx(ctx
);
188 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER
:
189 context_param
->u
.perf_counter
.name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
190 return lttng_add_perf_counter_to_ctx(context_param
->u
.perf_counter
.type
,
191 context_param
->u
.perf_counter
.config
,
192 context_param
->u
.perf_counter
.name
,
194 case LTTNG_KERNEL_CONTEXT_PROCNAME
:
195 return lttng_add_procname_to_ctx(ctx
);
196 case LTTNG_KERNEL_CONTEXT_HOSTNAME
:
197 return lttng_add_hostname_to_ctx(ctx
);
204 * lttng_ioctl - lttng syscall through ioctl
210 * This ioctl implements lttng commands:
211 * LTTNG_KERNEL_SESSION
212 * Returns a LTTng trace session file descriptor
213 * LTTNG_KERNEL_TRACER_VERSION
214 * Returns the LTTng kernel tracer version
215 * LTTNG_KERNEL_TRACEPOINT_LIST
216 * Returns a file descriptor listing available tracepoints
217 * LTTNG_KERNEL_WAIT_QUIESCENT
218 * Returns after all previously running probes have completed
219 * LTTNG_KERNEL_TRACER_ABI_VERSION
220 * Returns the LTTng kernel tracer ABI version
222 * The returned session will be deleted when its file descriptor is closed.
225 long lttng_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
228 case LTTNG_KERNEL_OLD_SESSION
:
229 case LTTNG_KERNEL_SESSION
:
230 return lttng_abi_create_session();
231 case LTTNG_KERNEL_OLD_TRACER_VERSION
:
233 struct lttng_kernel_tracer_version v
;
234 struct lttng_kernel_old_tracer_version oldv
;
235 struct lttng_kernel_old_tracer_version
*uversion
=
236 (struct lttng_kernel_old_tracer_version __user
*) arg
;
238 lttng_abi_tracer_version(&v
);
239 oldv
.major
= v
.major
;
240 oldv
.minor
= v
.minor
;
241 oldv
.patchlevel
= v
.patchlevel
;
243 if (copy_to_user(uversion
, &oldv
, sizeof(oldv
)))
247 case LTTNG_KERNEL_TRACER_VERSION
:
249 struct lttng_kernel_tracer_version version
;
250 struct lttng_kernel_tracer_version
*uversion
=
251 (struct lttng_kernel_tracer_version __user
*) arg
;
253 lttng_abi_tracer_version(&version
);
255 if (copy_to_user(uversion
, &version
, sizeof(version
)))
259 case LTTNG_KERNEL_TRACER_ABI_VERSION
:
261 struct lttng_kernel_tracer_abi_version version
;
262 struct lttng_kernel_tracer_abi_version
*uversion
=
263 (struct lttng_kernel_tracer_abi_version __user
*) arg
;
265 lttng_abi_tracer_abi_version(&version
);
267 if (copy_to_user(uversion
, &version
, sizeof(version
)))
271 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST
:
272 case LTTNG_KERNEL_TRACEPOINT_LIST
:
273 return lttng_abi_tracepoint_list();
274 case LTTNG_KERNEL_SYSCALL_LIST
:
275 return lttng_abi_syscall_list();
276 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT
:
277 case LTTNG_KERNEL_WAIT_QUIESCENT
:
280 case LTTNG_KERNEL_OLD_CALIBRATE
:
282 struct lttng_kernel_old_calibrate __user
*ucalibrate
=
283 (struct lttng_kernel_old_calibrate __user
*) arg
;
284 struct lttng_kernel_old_calibrate old_calibrate
;
285 struct lttng_kernel_calibrate calibrate
;
288 if (copy_from_user(&old_calibrate
, ucalibrate
, sizeof(old_calibrate
)))
290 calibrate
.type
= old_calibrate
.type
;
291 ret
= lttng_calibrate(&calibrate
);
292 if (copy_to_user(ucalibrate
, &old_calibrate
, sizeof(old_calibrate
)))
296 case LTTNG_KERNEL_CALIBRATE
:
298 struct lttng_kernel_calibrate __user
*ucalibrate
=
299 (struct lttng_kernel_calibrate __user
*) arg
;
300 struct lttng_kernel_calibrate calibrate
;
303 if (copy_from_user(&calibrate
, ucalibrate
, sizeof(calibrate
)))
305 ret
= lttng_calibrate(&calibrate
);
306 if (copy_to_user(ucalibrate
, &calibrate
, sizeof(calibrate
)))
315 static const struct file_operations lttng_fops
= {
316 .owner
= THIS_MODULE
,
317 .unlocked_ioctl
= lttng_ioctl
,
319 .compat_ioctl
= lttng_ioctl
,
324 int lttng_abi_create_channel(struct file
*session_file
,
325 struct lttng_kernel_channel
*chan_param
,
326 enum channel_type channel_type
)
328 struct lttng_session
*session
= session_file
->private_data
;
329 const struct file_operations
*fops
= NULL
;
330 const char *transport_name
;
331 struct lttng_channel
*chan
;
332 struct file
*chan_file
;
336 chan_fd
= lttng_get_unused_fd();
341 switch (channel_type
) {
342 case PER_CPU_CHANNEL
:
343 fops
= <tng_channel_fops
;
345 case METADATA_CHANNEL
:
346 fops
= <tng_metadata_fops
;
350 chan_file
= anon_inode_getfile("[lttng_channel]",
353 if (IS_ERR(chan_file
)) {
354 ret
= PTR_ERR(chan_file
);
357 switch (channel_type
) {
358 case PER_CPU_CHANNEL
:
359 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
) {
360 transport_name
= chan_param
->overwrite
?
361 "relay-overwrite" : "relay-discard";
362 } else if (chan_param
->output
== LTTNG_KERNEL_MMAP
) {
363 transport_name
= chan_param
->overwrite
?
364 "relay-overwrite-mmap" : "relay-discard-mmap";
369 case METADATA_CHANNEL
:
370 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
)
371 transport_name
= "relay-metadata";
372 else if (chan_param
->output
== LTTNG_KERNEL_MMAP
)
373 transport_name
= "relay-metadata-mmap";
378 transport_name
= "<unknown>";
382 * We tolerate no failure path after channel creation. It will stay
383 * invariant for the rest of the session.
385 chan
= lttng_channel_create(session
, transport_name
, NULL
,
386 chan_param
->subbuf_size
,
387 chan_param
->num_subbuf
,
388 chan_param
->switch_timer_interval
,
389 chan_param
->read_timer_interval
,
395 chan
->file
= chan_file
;
396 chan_file
->private_data
= chan
;
397 fd_install(chan_fd
, chan_file
);
398 atomic_long_inc(&session_file
->f_count
);
405 put_unused_fd(chan_fd
);
411 * lttng_session_ioctl - lttng session fd ioctl
417 * This ioctl implements lttng commands:
418 * LTTNG_KERNEL_CHANNEL
419 * Returns a LTTng channel file descriptor
420 * LTTNG_KERNEL_ENABLE
421 * Enables tracing for a session (weak enable)
422 * LTTNG_KERNEL_DISABLE
423 * Disables tracing for a session (strong disable)
424 * LTTNG_KERNEL_METADATA
425 * Returns a LTTng metadata file descriptor
426 * LTTNG_KERNEL_SESSION_TRACK_PID
427 * Add PID to session tracker
428 * LTTNG_KERNEL_SESSION_UNTRACK_PID
429 * Remove PID from session tracker
431 * The returned channel will be deleted when its file descriptor is closed.
434 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
436 struct lttng_session
*session
= file
->private_data
;
439 case LTTNG_KERNEL_OLD_CHANNEL
:
441 struct lttng_kernel_channel chan_param
;
442 struct lttng_kernel_old_channel old_chan_param
;
444 if (copy_from_user(&old_chan_param
,
445 (struct lttng_kernel_old_channel __user
*) arg
,
446 sizeof(struct lttng_kernel_old_channel
)))
448 chan_param
.overwrite
= old_chan_param
.overwrite
;
449 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
450 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
451 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
452 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
453 chan_param
.output
= old_chan_param
.output
;
455 return lttng_abi_create_channel(file
, &chan_param
,
458 case LTTNG_KERNEL_CHANNEL
:
460 struct lttng_kernel_channel chan_param
;
462 if (copy_from_user(&chan_param
,
463 (struct lttng_kernel_channel __user
*) arg
,
464 sizeof(struct lttng_kernel_channel
)))
466 return lttng_abi_create_channel(file
, &chan_param
,
469 case LTTNG_KERNEL_OLD_SESSION_START
:
470 case LTTNG_KERNEL_OLD_ENABLE
:
471 case LTTNG_KERNEL_SESSION_START
:
472 case LTTNG_KERNEL_ENABLE
:
473 return lttng_session_enable(session
);
474 case LTTNG_KERNEL_OLD_SESSION_STOP
:
475 case LTTNG_KERNEL_OLD_DISABLE
:
476 case LTTNG_KERNEL_SESSION_STOP
:
477 case LTTNG_KERNEL_DISABLE
:
478 return lttng_session_disable(session
);
479 case LTTNG_KERNEL_OLD_METADATA
:
481 struct lttng_kernel_channel chan_param
;
482 struct lttng_kernel_old_channel old_chan_param
;
484 if (copy_from_user(&old_chan_param
,
485 (struct lttng_kernel_old_channel __user
*) arg
,
486 sizeof(struct lttng_kernel_old_channel
)))
488 chan_param
.overwrite
= old_chan_param
.overwrite
;
489 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
490 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
491 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
492 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
493 chan_param
.output
= old_chan_param
.output
;
495 return lttng_abi_create_channel(file
, &chan_param
,
498 case LTTNG_KERNEL_METADATA
:
500 struct lttng_kernel_channel chan_param
;
502 if (copy_from_user(&chan_param
,
503 (struct lttng_kernel_channel __user
*) arg
,
504 sizeof(struct lttng_kernel_channel
)))
506 return lttng_abi_create_channel(file
, &chan_param
,
509 case LTTNG_KERNEL_SESSION_TRACK_PID
:
510 return lttng_session_track_pid(session
, (int) arg
);
511 case LTTNG_KERNEL_SESSION_UNTRACK_PID
:
512 return lttng_session_untrack_pid(session
, (int) arg
);
519 * Called when the last file reference is dropped.
521 * Big fat note: channels and events are invariant for the whole session after
522 * their creation. So this session destruction also destroys all channel and
523 * event structures specific to this session (they are not destroyed when their
524 * individual file is released).
527 int lttng_session_release(struct inode
*inode
, struct file
*file
)
529 struct lttng_session
*session
= file
->private_data
;
532 lttng_session_destroy(session
);
536 static const struct file_operations lttng_session_fops
= {
537 .owner
= THIS_MODULE
,
538 .release
= lttng_session_release
,
539 .unlocked_ioctl
= lttng_session_ioctl
,
541 .compat_ioctl
= lttng_session_ioctl
,
546 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
550 * Handles the poll operations for the metadata channels.
553 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
556 struct lttng_metadata_stream
*stream
= filp
->private_data
;
557 struct lib_ring_buffer
*buf
= stream
->priv
;
559 unsigned int mask
= 0;
561 if (filp
->f_mode
& FMODE_READ
) {
562 poll_wait_set_exclusive(wait
);
563 poll_wait(filp
, &stream
->read_wait
, wait
);
565 finalized
= stream
->finalized
;
568 * lib_ring_buffer_is_finalized() contains a smp_rmb()
569 * ordering finalized load before offsets loads.
571 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
576 if (stream
->metadata_cache
->metadata_written
>
577 stream
->metadata_out
)
585 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
586 unsigned int cmd
, unsigned long arg
)
588 struct lttng_metadata_stream
*stream
= filp
->private_data
;
590 stream
->metadata_out
= stream
->metadata_in
;
594 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
595 unsigned int cmd
, unsigned long arg
)
598 struct lttng_metadata_stream
*stream
= filp
->private_data
;
599 struct lib_ring_buffer
*buf
= stream
->priv
;
602 case RING_BUFFER_GET_NEXT_SUBBUF
:
604 struct lttng_metadata_stream
*stream
= filp
->private_data
;
605 struct lib_ring_buffer
*buf
= stream
->priv
;
606 struct channel
*chan
= buf
->backend
.chan
;
608 ret
= lttng_metadata_output_channel(stream
, chan
);
610 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
616 case RING_BUFFER_GET_SUBBUF
:
619 * Random access is not allowed for metadata channel.
623 case RING_BUFFER_FLUSH
:
625 struct lttng_metadata_stream
*stream
= filp
->private_data
;
626 struct lib_ring_buffer
*buf
= stream
->priv
;
627 struct channel
*chan
= buf
->backend
.chan
;
630 * Before doing the actual ring buffer flush, write up to one
631 * packet of metadata in the ring buffer.
633 ret
= lttng_metadata_output_channel(stream
, chan
);
641 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
643 /* Performing lib ring buffer ioctl after our own. */
644 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
649 case RING_BUFFER_PUT_NEXT_SUBBUF
:
651 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
664 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
665 unsigned int cmd
, unsigned long arg
)
668 struct lttng_metadata_stream
*stream
= filp
->private_data
;
669 struct lib_ring_buffer
*buf
= stream
->priv
;
672 case RING_BUFFER_GET_NEXT_SUBBUF
:
674 struct lttng_metadata_stream
*stream
= filp
->private_data
;
675 struct lib_ring_buffer
*buf
= stream
->priv
;
676 struct channel
*chan
= buf
->backend
.chan
;
678 ret
= lttng_metadata_output_channel(stream
, chan
);
680 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
686 case RING_BUFFER_GET_SUBBUF
:
689 * Random access is not allowed for metadata channel.
696 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
698 /* Performing lib ring buffer ioctl after our own. */
699 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
704 case RING_BUFFER_PUT_NEXT_SUBBUF
:
706 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
719 * This is not used by anonymous file descriptors. This code is left
720 * there if we ever want to implement an inode with open() operation.
723 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
725 struct lttng_metadata_stream
*stream
= inode
->i_private
;
726 struct lib_ring_buffer
*buf
= stream
->priv
;
728 file
->private_data
= buf
;
730 * Since life-time of metadata cache differs from that of
731 * session, we need to keep our own reference on the transport.
733 if (!try_module_get(stream
->transport
->owner
)) {
734 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
737 return lib_ring_buffer_open(inode
, file
, buf
);
741 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
743 struct lttng_metadata_stream
*stream
= file
->private_data
;
744 struct lib_ring_buffer
*buf
= stream
->priv
;
746 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
747 module_put(stream
->transport
->owner
);
748 return lib_ring_buffer_release(inode
, file
, buf
);
752 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
753 struct pipe_inode_info
*pipe
, size_t len
,
756 struct lttng_metadata_stream
*stream
= in
->private_data
;
757 struct lib_ring_buffer
*buf
= stream
->priv
;
759 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
764 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
765 struct vm_area_struct
*vma
)
767 struct lttng_metadata_stream
*stream
= filp
->private_data
;
768 struct lib_ring_buffer
*buf
= stream
->priv
;
770 return lib_ring_buffer_mmap(filp
, vma
, buf
);
774 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
775 .owner
= THIS_MODULE
,
776 .open
= lttng_metadata_ring_buffer_open
,
777 .release
= lttng_metadata_ring_buffer_release
,
778 .poll
= lttng_metadata_ring_buffer_poll
,
779 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
780 .mmap
= lttng_metadata_ring_buffer_mmap
,
781 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
782 .llseek
= vfs_lib_ring_buffer_no_llseek
,
784 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
789 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
790 const struct file_operations
*fops
)
793 struct file
*stream_file
;
795 stream_fd
= lttng_get_unused_fd();
800 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
801 stream_priv
, O_RDWR
);
802 if (IS_ERR(stream_file
)) {
803 ret
= PTR_ERR(stream_file
);
807 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
808 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
809 * file descriptor, so we set FMODE_PREAD here.
811 stream_file
->f_mode
|= FMODE_PREAD
;
812 fd_install(stream_fd
, stream_file
);
814 * The stream holds a reference to the channel within the generic ring
815 * buffer library, so no need to hold a refcount on the channel and
816 * session files here.
821 put_unused_fd(stream_fd
);
827 int lttng_abi_open_stream(struct file
*channel_file
)
829 struct lttng_channel
*channel
= channel_file
->private_data
;
830 struct lib_ring_buffer
*buf
;
834 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
839 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
840 <tng_stream_ring_buffer_file_operations
);
847 channel
->ops
->buffer_read_close(buf
);
852 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
854 struct lttng_channel
*channel
= channel_file
->private_data
;
855 struct lttng_session
*session
= channel
->session
;
856 struct lib_ring_buffer
*buf
;
858 struct lttng_metadata_stream
*metadata_stream
;
861 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
865 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
867 if (!metadata_stream
) {
871 metadata_stream
->metadata_cache
= session
->metadata_cache
;
872 init_waitqueue_head(&metadata_stream
->read_wait
);
873 metadata_stream
->priv
= buf
;
874 stream_priv
= metadata_stream
;
875 metadata_stream
->transport
= channel
->transport
;
876 mutex_init(&metadata_stream
->lock
);
879 * Since life-time of metadata cache differs from that of
880 * session, we need to keep our own reference on the transport.
882 if (!try_module_get(metadata_stream
->transport
->owner
)) {
883 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
888 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
889 <tng_metadata_ring_buffer_file_operations
);
893 kref_get(&session
->metadata_cache
->refcount
);
894 list_add(&metadata_stream
->list
,
895 &session
->metadata_cache
->metadata_stream
);
899 module_put(metadata_stream
->transport
->owner
);
901 kfree(metadata_stream
);
903 channel
->ops
->buffer_read_close(buf
);
908 int lttng_abi_create_event(struct file
*channel_file
,
909 struct lttng_kernel_event
*event_param
)
911 struct lttng_channel
*channel
= channel_file
->private_data
;
912 struct lttng_event
*event
;
914 struct file
*event_file
;
916 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
917 switch (event_param
->instrumentation
) {
918 case LTTNG_KERNEL_KRETPROBE
:
919 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
921 case LTTNG_KERNEL_KPROBE
:
922 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
924 case LTTNG_KERNEL_FUNCTION
:
925 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
930 switch (event_param
->instrumentation
) {
932 event_fd
= lttng_get_unused_fd();
937 event_file
= anon_inode_getfile("[lttng_event]",
940 if (IS_ERR(event_file
)) {
941 ret
= PTR_ERR(event_file
);
945 * We tolerate no failure path after event creation. It
946 * will stay invariant for the rest of the session.
948 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
949 WARN_ON_ONCE(!event
);
951 ret
= PTR_ERR(event
);
954 event_file
->private_data
= event
;
955 fd_install(event_fd
, event_file
);
956 /* The event holds a reference on the channel */
957 atomic_long_inc(&channel_file
->f_count
);
959 case LTTNG_KERNEL_SYSCALL
:
960 ret
= lttng_syscalls_register(channel
, NULL
);
964 if (event_param
->u
.syscall
.enable
) {
965 ret
= lttng_syscall_filter_enable(channel
,
966 event_param
->name
[0] == '\0' ?
967 NULL
: event_param
->name
);
972 ret
= lttng_syscall_filter_disable(channel
,
973 event_param
->name
[0] == '\0' ?
974 NULL
: event_param
->name
);
985 put_unused_fd(event_fd
);
991 * lttng_channel_ioctl - lttng syscall through ioctl
997 * This ioctl implements lttng commands:
998 * LTTNG_KERNEL_STREAM
999 * Returns an event stream file descriptor or failure.
1000 * (typically, one event stream records events from one CPU)
1001 * LTTNG_KERNEL_EVENT
1002 * Returns an event file descriptor or failure.
1003 * LTTNG_KERNEL_CONTEXT
1004 * Prepend a context field to each event in the channel
1005 * LTTNG_KERNEL_ENABLE
1006 * Enable recording for events in this channel (weak enable)
1007 * LTTNG_KERNEL_DISABLE
1008 * Disable recording for events in this channel (strong disable)
1010 * Channel and event file descriptors also hold a reference on the session.
1013 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1015 struct lttng_channel
*channel
= file
->private_data
;
1018 case LTTNG_KERNEL_OLD_STREAM
:
1019 case LTTNG_KERNEL_STREAM
:
1020 return lttng_abi_open_stream(file
);
1021 case LTTNG_KERNEL_OLD_EVENT
:
1023 struct lttng_kernel_event
*uevent_param
;
1024 struct lttng_kernel_old_event
*old_uevent_param
;
1027 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1029 if (!uevent_param
) {
1033 old_uevent_param
= kmalloc(
1034 sizeof(struct lttng_kernel_old_event
),
1036 if (!old_uevent_param
) {
1038 goto old_event_error_free_param
;
1040 if (copy_from_user(old_uevent_param
,
1041 (struct lttng_kernel_old_event __user
*) arg
,
1042 sizeof(struct lttng_kernel_old_event
))) {
1044 goto old_event_error_free_old_param
;
1047 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1048 sizeof(uevent_param
->name
));
1049 uevent_param
->instrumentation
=
1050 old_uevent_param
->instrumentation
;
1052 switch (old_uevent_param
->instrumentation
) {
1053 case LTTNG_KERNEL_KPROBE
:
1054 uevent_param
->u
.kprobe
.addr
=
1055 old_uevent_param
->u
.kprobe
.addr
;
1056 uevent_param
->u
.kprobe
.offset
=
1057 old_uevent_param
->u
.kprobe
.offset
;
1058 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1059 old_uevent_param
->u
.kprobe
.symbol_name
,
1060 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1062 case LTTNG_KERNEL_KRETPROBE
:
1063 uevent_param
->u
.kretprobe
.addr
=
1064 old_uevent_param
->u
.kretprobe
.addr
;
1065 uevent_param
->u
.kretprobe
.offset
=
1066 old_uevent_param
->u
.kretprobe
.offset
;
1067 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1068 old_uevent_param
->u
.kretprobe
.symbol_name
,
1069 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1071 case LTTNG_KERNEL_FUNCTION
:
1072 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1073 old_uevent_param
->u
.ftrace
.symbol_name
,
1074 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1079 ret
= lttng_abi_create_event(file
, uevent_param
);
1081 old_event_error_free_old_param
:
1082 kfree(old_uevent_param
);
1083 old_event_error_free_param
:
1084 kfree(uevent_param
);
1088 case LTTNG_KERNEL_EVENT
:
1090 struct lttng_kernel_event uevent_param
;
1092 if (copy_from_user(&uevent_param
,
1093 (struct lttng_kernel_event __user
*) arg
,
1094 sizeof(uevent_param
)))
1096 return lttng_abi_create_event(file
, &uevent_param
);
1098 case LTTNG_KERNEL_OLD_CONTEXT
:
1100 struct lttng_kernel_context
*ucontext_param
;
1101 struct lttng_kernel_old_context
*old_ucontext_param
;
1104 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1106 if (!ucontext_param
) {
1110 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1112 if (!old_ucontext_param
) {
1114 goto old_ctx_error_free_param
;
1117 if (copy_from_user(old_ucontext_param
,
1118 (struct lttng_kernel_old_context __user
*) arg
,
1119 sizeof(struct lttng_kernel_old_context
))) {
1121 goto old_ctx_error_free_old_param
;
1123 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1124 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1125 sizeof(ucontext_param
->padding
));
1126 /* only type that uses the union */
1127 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1128 ucontext_param
->u
.perf_counter
.type
=
1129 old_ucontext_param
->u
.perf_counter
.type
;
1130 ucontext_param
->u
.perf_counter
.config
=
1131 old_ucontext_param
->u
.perf_counter
.config
;
1132 memcpy(ucontext_param
->u
.perf_counter
.name
,
1133 old_ucontext_param
->u
.perf_counter
.name
,
1134 sizeof(ucontext_param
->u
.perf_counter
.name
));
1137 ret
= lttng_abi_add_context(file
,
1139 &channel
->ctx
, channel
->session
);
1141 old_ctx_error_free_old_param
:
1142 kfree(old_ucontext_param
);
1143 old_ctx_error_free_param
:
1144 kfree(ucontext_param
);
1148 case LTTNG_KERNEL_CONTEXT
:
1150 struct lttng_kernel_context ucontext_param
;
1152 if (copy_from_user(&ucontext_param
,
1153 (struct lttng_kernel_context __user
*) arg
,
1154 sizeof(ucontext_param
)))
1156 return lttng_abi_add_context(file
,
1158 &channel
->ctx
, channel
->session
);
1160 case LTTNG_KERNEL_OLD_ENABLE
:
1161 case LTTNG_KERNEL_ENABLE
:
1162 return lttng_channel_enable(channel
);
1163 case LTTNG_KERNEL_OLD_DISABLE
:
1164 case LTTNG_KERNEL_DISABLE
:
1165 return lttng_channel_disable(channel
);
1166 case LTTNG_KERNEL_SYSCALL_MASK
:
1167 return lttng_channel_syscall_mask(channel
,
1168 (struct lttng_kernel_syscall_mask __user
*) arg
);
1170 return -ENOIOCTLCMD
;
1176 * lttng_metadata_ioctl - lttng syscall through ioctl
1182 * This ioctl implements lttng commands:
1183 * LTTNG_KERNEL_STREAM
1184 * Returns an event stream file descriptor or failure.
1186 * Channel and event file descriptors also hold a reference on the session.
1189 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1192 case LTTNG_KERNEL_OLD_STREAM
:
1193 case LTTNG_KERNEL_STREAM
:
1194 return lttng_abi_open_metadata_stream(file
);
1196 return -ENOIOCTLCMD
;
1201 * lttng_channel_poll - lttng stream addition/removal monitoring
1206 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1208 struct lttng_channel
*channel
= file
->private_data
;
1209 unsigned int mask
= 0;
1211 if (file
->f_mode
& FMODE_READ
) {
1212 poll_wait_set_exclusive(wait
);
1213 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1216 if (channel
->ops
->is_disabled(channel
->chan
))
1218 if (channel
->ops
->is_finalized(channel
->chan
))
1220 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1221 return POLLIN
| POLLRDNORM
;
1229 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1231 struct lttng_channel
*channel
= file
->private_data
;
1234 fput(channel
->session
->file
);
1239 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1241 struct lttng_channel
*channel
= file
->private_data
;
1244 lttng_metadata_channel_destroy(channel
);
1245 fput(channel
->session
->file
);
1251 static const struct file_operations lttng_channel_fops
= {
1252 .owner
= THIS_MODULE
,
1253 .release
= lttng_channel_release
,
1254 .poll
= lttng_channel_poll
,
1255 .unlocked_ioctl
= lttng_channel_ioctl
,
1256 #ifdef CONFIG_COMPAT
1257 .compat_ioctl
= lttng_channel_ioctl
,
1261 static const struct file_operations lttng_metadata_fops
= {
1262 .owner
= THIS_MODULE
,
1263 .release
= lttng_metadata_channel_release
,
1264 .unlocked_ioctl
= lttng_metadata_ioctl
,
1265 #ifdef CONFIG_COMPAT
1266 .compat_ioctl
= lttng_metadata_ioctl
,
1271 * lttng_event_ioctl - lttng syscall through ioctl
1277 * This ioctl implements lttng commands:
1278 * LTTNG_KERNEL_CONTEXT
1279 * Prepend a context field to each record of this event
1280 * LTTNG_KERNEL_ENABLE
1281 * Enable recording for this event (weak enable)
1282 * LTTNG_KERNEL_DISABLE
1283 * Disable recording for this event (strong disable)
1286 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1288 struct lttng_event
*event
= file
->private_data
;
1291 case LTTNG_KERNEL_OLD_CONTEXT
:
1293 struct lttng_kernel_context
*ucontext_param
;
1294 struct lttng_kernel_old_context
*old_ucontext_param
;
1297 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1299 if (!ucontext_param
) {
1303 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1305 if (!old_ucontext_param
) {
1307 goto old_ctx_error_free_param
;
1310 if (copy_from_user(old_ucontext_param
,
1311 (struct lttng_kernel_old_context __user
*) arg
,
1312 sizeof(struct lttng_kernel_old_context
))) {
1314 goto old_ctx_error_free_old_param
;
1316 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1317 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1318 sizeof(ucontext_param
->padding
));
1319 /* only type that uses the union */
1320 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1321 ucontext_param
->u
.perf_counter
.type
=
1322 old_ucontext_param
->u
.perf_counter
.type
;
1323 ucontext_param
->u
.perf_counter
.config
=
1324 old_ucontext_param
->u
.perf_counter
.config
;
1325 memcpy(ucontext_param
->u
.perf_counter
.name
,
1326 old_ucontext_param
->u
.perf_counter
.name
,
1327 sizeof(ucontext_param
->u
.perf_counter
.name
));
1330 ret
= lttng_abi_add_context(file
,
1332 &event
->ctx
, event
->chan
->session
);
1334 old_ctx_error_free_old_param
:
1335 kfree(old_ucontext_param
);
1336 old_ctx_error_free_param
:
1337 kfree(ucontext_param
);
1341 case LTTNG_KERNEL_CONTEXT
:
1343 struct lttng_kernel_context ucontext_param
;
1345 if (copy_from_user(&ucontext_param
,
1346 (struct lttng_kernel_context __user
*) arg
,
1347 sizeof(ucontext_param
)))
1349 return lttng_abi_add_context(file
,
1351 &event
->ctx
, event
->chan
->session
);
1353 case LTTNG_KERNEL_OLD_ENABLE
:
1354 case LTTNG_KERNEL_ENABLE
:
1355 return lttng_event_enable(event
);
1356 case LTTNG_KERNEL_OLD_DISABLE
:
1357 case LTTNG_KERNEL_DISABLE
:
1358 return lttng_event_disable(event
);
1360 return -ENOIOCTLCMD
;
1365 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1367 struct lttng_event
*event
= file
->private_data
;
1370 fput(event
->chan
->file
);
1374 /* TODO: filter control ioctl */
1375 static const struct file_operations lttng_event_fops
= {
1376 .owner
= THIS_MODULE
,
1377 .release
= lttng_event_release
,
1378 .unlocked_ioctl
= lttng_event_ioctl
,
1379 #ifdef CONFIG_COMPAT
1380 .compat_ioctl
= lttng_event_ioctl
,
1384 static int put_u64(uint64_t val
, unsigned long arg
)
1386 return put_user(val
, (uint64_t __user
*) arg
);
1389 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1390 unsigned int cmd
, unsigned long arg
)
1392 struct lib_ring_buffer
*buf
= filp
->private_data
;
1393 struct channel
*chan
= buf
->backend
.chan
;
1394 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1395 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1398 if (atomic_read(&chan
->record_disabled
))
1402 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1406 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1409 return put_u64(ts
, arg
);
1411 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1415 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1418 return put_u64(ts
, arg
);
1420 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1424 ret
= ops
->events_discarded(config
, buf
, &ed
);
1427 return put_u64(ed
, arg
);
1429 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1433 ret
= ops
->content_size(config
, buf
, &cs
);
1436 return put_u64(cs
, arg
);
1438 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1442 ret
= ops
->packet_size(config
, buf
, &ps
);
1445 return put_u64(ps
, arg
);
1447 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1451 ret
= ops
->stream_id(config
, buf
, &si
);
1454 return put_u64(si
, arg
);
1456 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1460 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1463 return put_u64(ts
, arg
);
1466 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1474 #ifdef CONFIG_COMPAT
1475 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1476 unsigned int cmd
, unsigned long arg
)
1478 struct lib_ring_buffer
*buf
= filp
->private_data
;
1479 struct channel
*chan
= buf
->backend
.chan
;
1480 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1481 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1484 if (atomic_read(&chan
->record_disabled
))
1488 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1492 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1495 return put_u64(ts
, arg
);
1497 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1501 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1504 return put_u64(ts
, arg
);
1506 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1510 ret
= ops
->events_discarded(config
, buf
, &ed
);
1513 return put_u64(ed
, arg
);
1515 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1519 ret
= ops
->content_size(config
, buf
, &cs
);
1522 return put_u64(cs
, arg
);
1524 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1528 ret
= ops
->packet_size(config
, buf
, &ps
);
1531 return put_u64(ps
, arg
);
1533 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1537 ret
= ops
->stream_id(config
, buf
, &si
);
1540 return put_u64(si
, arg
);
1542 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1546 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1549 return put_u64(ts
, arg
);
1552 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1559 #endif /* CONFIG_COMPAT */
1561 static void lttng_stream_override_ring_buffer_fops(void)
1563 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1564 lttng_stream_ring_buffer_file_operations
.open
=
1565 lib_ring_buffer_file_operations
.open
;
1566 lttng_stream_ring_buffer_file_operations
.release
=
1567 lib_ring_buffer_file_operations
.release
;
1568 lttng_stream_ring_buffer_file_operations
.poll
=
1569 lib_ring_buffer_file_operations
.poll
;
1570 lttng_stream_ring_buffer_file_operations
.splice_read
=
1571 lib_ring_buffer_file_operations
.splice_read
;
1572 lttng_stream_ring_buffer_file_operations
.mmap
=
1573 lib_ring_buffer_file_operations
.mmap
;
1574 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1575 lttng_stream_ring_buffer_ioctl
;
1576 lttng_stream_ring_buffer_file_operations
.llseek
=
1577 lib_ring_buffer_file_operations
.llseek
;
1578 #ifdef CONFIG_COMPAT
1579 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1580 lttng_stream_ring_buffer_compat_ioctl
;
1584 int __init
lttng_abi_init(void)
1588 wrapper_vmalloc_sync_all();
1589 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1592 if (!lttng_proc_dentry
) {
1593 printk(KERN_ERR
"Error creating LTTng control file\n");
1597 lttng_stream_override_ring_buffer_fops();
1603 /* No __exit annotation because used by init error path too. */
1604 void lttng_abi_exit(void)
1606 if (lttng_proc_dentry
)
1607 remove_proc_entry("lttng", NULL
);