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
);
513 case LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS
:
514 return lttng_session_list_tracker_pids(session
);
521 * Called when the last file reference is dropped.
523 * Big fat note: channels and events are invariant for the whole session after
524 * their creation. So this session destruction also destroys all channel and
525 * event structures specific to this session (they are not destroyed when their
526 * individual file is released).
529 int lttng_session_release(struct inode
*inode
, struct file
*file
)
531 struct lttng_session
*session
= file
->private_data
;
534 lttng_session_destroy(session
);
538 static const struct file_operations lttng_session_fops
= {
539 .owner
= THIS_MODULE
,
540 .release
= lttng_session_release
,
541 .unlocked_ioctl
= lttng_session_ioctl
,
543 .compat_ioctl
= lttng_session_ioctl
,
548 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
552 * Handles the poll operations for the metadata channels.
555 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
558 struct lttng_metadata_stream
*stream
= filp
->private_data
;
559 struct lib_ring_buffer
*buf
= stream
->priv
;
561 unsigned int mask
= 0;
563 if (filp
->f_mode
& FMODE_READ
) {
564 poll_wait_set_exclusive(wait
);
565 poll_wait(filp
, &stream
->read_wait
, wait
);
567 finalized
= stream
->finalized
;
570 * lib_ring_buffer_is_finalized() contains a smp_rmb()
571 * ordering finalized load before offsets loads.
573 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
578 if (stream
->metadata_cache
->metadata_written
>
579 stream
->metadata_out
)
587 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
588 unsigned int cmd
, unsigned long arg
)
590 struct lttng_metadata_stream
*stream
= filp
->private_data
;
592 stream
->metadata_out
= stream
->metadata_in
;
596 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
597 unsigned int cmd
, unsigned long arg
)
600 struct lttng_metadata_stream
*stream
= filp
->private_data
;
601 struct lib_ring_buffer
*buf
= stream
->priv
;
604 case RING_BUFFER_GET_NEXT_SUBBUF
:
606 struct lttng_metadata_stream
*stream
= filp
->private_data
;
607 struct lib_ring_buffer
*buf
= stream
->priv
;
608 struct channel
*chan
= buf
->backend
.chan
;
610 ret
= lttng_metadata_output_channel(stream
, chan
);
612 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
618 case RING_BUFFER_GET_SUBBUF
:
621 * Random access is not allowed for metadata channel.
625 case RING_BUFFER_FLUSH
:
627 struct lttng_metadata_stream
*stream
= filp
->private_data
;
628 struct lib_ring_buffer
*buf
= stream
->priv
;
629 struct channel
*chan
= buf
->backend
.chan
;
632 * Before doing the actual ring buffer flush, write up to one
633 * packet of metadata in the ring buffer.
635 ret
= lttng_metadata_output_channel(stream
, chan
);
643 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
645 /* Performing lib ring buffer ioctl after our own. */
646 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
651 case RING_BUFFER_PUT_NEXT_SUBBUF
:
653 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
666 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
667 unsigned int cmd
, unsigned long arg
)
670 struct lttng_metadata_stream
*stream
= filp
->private_data
;
671 struct lib_ring_buffer
*buf
= stream
->priv
;
674 case RING_BUFFER_GET_NEXT_SUBBUF
:
676 struct lttng_metadata_stream
*stream
= filp
->private_data
;
677 struct lib_ring_buffer
*buf
= stream
->priv
;
678 struct channel
*chan
= buf
->backend
.chan
;
680 ret
= lttng_metadata_output_channel(stream
, chan
);
682 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
688 case RING_BUFFER_GET_SUBBUF
:
691 * Random access is not allowed for metadata channel.
698 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
700 /* Performing lib ring buffer ioctl after our own. */
701 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
706 case RING_BUFFER_PUT_NEXT_SUBBUF
:
708 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
721 * This is not used by anonymous file descriptors. This code is left
722 * there if we ever want to implement an inode with open() operation.
725 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
727 struct lttng_metadata_stream
*stream
= inode
->i_private
;
728 struct lib_ring_buffer
*buf
= stream
->priv
;
730 file
->private_data
= buf
;
732 * Since life-time of metadata cache differs from that of
733 * session, we need to keep our own reference on the transport.
735 if (!try_module_get(stream
->transport
->owner
)) {
736 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
739 return lib_ring_buffer_open(inode
, file
, buf
);
743 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
745 struct lttng_metadata_stream
*stream
= file
->private_data
;
746 struct lib_ring_buffer
*buf
= stream
->priv
;
748 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
749 module_put(stream
->transport
->owner
);
750 return lib_ring_buffer_release(inode
, file
, buf
);
754 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
755 struct pipe_inode_info
*pipe
, size_t len
,
758 struct lttng_metadata_stream
*stream
= in
->private_data
;
759 struct lib_ring_buffer
*buf
= stream
->priv
;
761 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
766 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
767 struct vm_area_struct
*vma
)
769 struct lttng_metadata_stream
*stream
= filp
->private_data
;
770 struct lib_ring_buffer
*buf
= stream
->priv
;
772 return lib_ring_buffer_mmap(filp
, vma
, buf
);
776 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
777 .owner
= THIS_MODULE
,
778 .open
= lttng_metadata_ring_buffer_open
,
779 .release
= lttng_metadata_ring_buffer_release
,
780 .poll
= lttng_metadata_ring_buffer_poll
,
781 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
782 .mmap
= lttng_metadata_ring_buffer_mmap
,
783 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
784 .llseek
= vfs_lib_ring_buffer_no_llseek
,
786 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
791 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
792 const struct file_operations
*fops
)
795 struct file
*stream_file
;
797 stream_fd
= lttng_get_unused_fd();
802 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
803 stream_priv
, O_RDWR
);
804 if (IS_ERR(stream_file
)) {
805 ret
= PTR_ERR(stream_file
);
809 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
810 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
811 * file descriptor, so we set FMODE_PREAD here.
813 stream_file
->f_mode
|= FMODE_PREAD
;
814 fd_install(stream_fd
, stream_file
);
816 * The stream holds a reference to the channel within the generic ring
817 * buffer library, so no need to hold a refcount on the channel and
818 * session files here.
823 put_unused_fd(stream_fd
);
829 int lttng_abi_open_stream(struct file
*channel_file
)
831 struct lttng_channel
*channel
= channel_file
->private_data
;
832 struct lib_ring_buffer
*buf
;
836 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
841 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
842 <tng_stream_ring_buffer_file_operations
);
849 channel
->ops
->buffer_read_close(buf
);
854 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
856 struct lttng_channel
*channel
= channel_file
->private_data
;
857 struct lttng_session
*session
= channel
->session
;
858 struct lib_ring_buffer
*buf
;
860 struct lttng_metadata_stream
*metadata_stream
;
863 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
867 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
869 if (!metadata_stream
) {
873 metadata_stream
->metadata_cache
= session
->metadata_cache
;
874 init_waitqueue_head(&metadata_stream
->read_wait
);
875 metadata_stream
->priv
= buf
;
876 stream_priv
= metadata_stream
;
877 metadata_stream
->transport
= channel
->transport
;
878 mutex_init(&metadata_stream
->lock
);
881 * Since life-time of metadata cache differs from that of
882 * session, we need to keep our own reference on the transport.
884 if (!try_module_get(metadata_stream
->transport
->owner
)) {
885 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
890 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
891 <tng_metadata_ring_buffer_file_operations
);
895 kref_get(&session
->metadata_cache
->refcount
);
896 list_add(&metadata_stream
->list
,
897 &session
->metadata_cache
->metadata_stream
);
901 module_put(metadata_stream
->transport
->owner
);
903 kfree(metadata_stream
);
905 channel
->ops
->buffer_read_close(buf
);
910 int lttng_abi_create_event(struct file
*channel_file
,
911 struct lttng_kernel_event
*event_param
)
913 struct lttng_channel
*channel
= channel_file
->private_data
;
915 struct file
*event_file
;
918 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
919 switch (event_param
->instrumentation
) {
920 case LTTNG_KERNEL_KRETPROBE
:
921 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
923 case LTTNG_KERNEL_KPROBE
:
924 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
926 case LTTNG_KERNEL_FUNCTION
:
927 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
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
);
944 if (event_param
->instrumentation
== LTTNG_KERNEL_TRACEPOINT
945 || event_param
->instrumentation
== LTTNG_KERNEL_SYSCALL
) {
946 struct lttng_enabler
*enabler
;
948 if (event_param
->name
[strlen(event_param
->name
) - 1] == '*') {
949 enabler
= lttng_enabler_create(LTTNG_ENABLER_WILDCARD
,
950 event_param
, channel
);
952 enabler
= lttng_enabler_create(LTTNG_ENABLER_NAME
,
953 event_param
, channel
);
957 struct lttng_event
*event
;
960 * We tolerate no failure path after event creation. It
961 * will stay invariant for the rest of the session.
963 event
= lttng_event_create(channel
, event_param
,
965 event_param
->instrumentation
);
966 WARN_ON_ONCE(!event
);
968 ret
= PTR_ERR(event
);
973 event_file
->private_data
= priv
;
974 fd_install(event_fd
, event_file
);
975 /* The event holds a reference on the channel */
976 atomic_long_inc(&channel_file
->f_count
);
982 put_unused_fd(event_fd
);
988 * lttng_channel_ioctl - lttng syscall through ioctl
994 * This ioctl implements lttng commands:
995 * LTTNG_KERNEL_STREAM
996 * Returns an event stream file descriptor or failure.
997 * (typically, one event stream records events from one CPU)
999 * Returns an event file descriptor or failure.
1000 * LTTNG_KERNEL_CONTEXT
1001 * Prepend a context field to each event in the channel
1002 * LTTNG_KERNEL_ENABLE
1003 * Enable recording for events in this channel (weak enable)
1004 * LTTNG_KERNEL_DISABLE
1005 * Disable recording for events in this channel (strong disable)
1007 * Channel and event file descriptors also hold a reference on the session.
1010 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1012 struct lttng_channel
*channel
= file
->private_data
;
1015 case LTTNG_KERNEL_OLD_STREAM
:
1016 case LTTNG_KERNEL_STREAM
:
1017 return lttng_abi_open_stream(file
);
1018 case LTTNG_KERNEL_OLD_EVENT
:
1020 struct lttng_kernel_event
*uevent_param
;
1021 struct lttng_kernel_old_event
*old_uevent_param
;
1024 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1026 if (!uevent_param
) {
1030 old_uevent_param
= kmalloc(
1031 sizeof(struct lttng_kernel_old_event
),
1033 if (!old_uevent_param
) {
1035 goto old_event_error_free_param
;
1037 if (copy_from_user(old_uevent_param
,
1038 (struct lttng_kernel_old_event __user
*) arg
,
1039 sizeof(struct lttng_kernel_old_event
))) {
1041 goto old_event_error_free_old_param
;
1044 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1045 sizeof(uevent_param
->name
));
1046 uevent_param
->instrumentation
=
1047 old_uevent_param
->instrumentation
;
1049 switch (old_uevent_param
->instrumentation
) {
1050 case LTTNG_KERNEL_KPROBE
:
1051 uevent_param
->u
.kprobe
.addr
=
1052 old_uevent_param
->u
.kprobe
.addr
;
1053 uevent_param
->u
.kprobe
.offset
=
1054 old_uevent_param
->u
.kprobe
.offset
;
1055 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1056 old_uevent_param
->u
.kprobe
.symbol_name
,
1057 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1059 case LTTNG_KERNEL_KRETPROBE
:
1060 uevent_param
->u
.kretprobe
.addr
=
1061 old_uevent_param
->u
.kretprobe
.addr
;
1062 uevent_param
->u
.kretprobe
.offset
=
1063 old_uevent_param
->u
.kretprobe
.offset
;
1064 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1065 old_uevent_param
->u
.kretprobe
.symbol_name
,
1066 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1068 case LTTNG_KERNEL_FUNCTION
:
1069 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1070 old_uevent_param
->u
.ftrace
.symbol_name
,
1071 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1076 ret
= lttng_abi_create_event(file
, uevent_param
);
1078 old_event_error_free_old_param
:
1079 kfree(old_uevent_param
);
1080 old_event_error_free_param
:
1081 kfree(uevent_param
);
1085 case LTTNG_KERNEL_EVENT
:
1087 struct lttng_kernel_event uevent_param
;
1089 if (copy_from_user(&uevent_param
,
1090 (struct lttng_kernel_event __user
*) arg
,
1091 sizeof(uevent_param
)))
1093 return lttng_abi_create_event(file
, &uevent_param
);
1095 case LTTNG_KERNEL_OLD_CONTEXT
:
1097 struct lttng_kernel_context
*ucontext_param
;
1098 struct lttng_kernel_old_context
*old_ucontext_param
;
1101 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1103 if (!ucontext_param
) {
1107 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1109 if (!old_ucontext_param
) {
1111 goto old_ctx_error_free_param
;
1114 if (copy_from_user(old_ucontext_param
,
1115 (struct lttng_kernel_old_context __user
*) arg
,
1116 sizeof(struct lttng_kernel_old_context
))) {
1118 goto old_ctx_error_free_old_param
;
1120 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1121 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1122 sizeof(ucontext_param
->padding
));
1123 /* only type that uses the union */
1124 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1125 ucontext_param
->u
.perf_counter
.type
=
1126 old_ucontext_param
->u
.perf_counter
.type
;
1127 ucontext_param
->u
.perf_counter
.config
=
1128 old_ucontext_param
->u
.perf_counter
.config
;
1129 memcpy(ucontext_param
->u
.perf_counter
.name
,
1130 old_ucontext_param
->u
.perf_counter
.name
,
1131 sizeof(ucontext_param
->u
.perf_counter
.name
));
1134 ret
= lttng_abi_add_context(file
,
1136 &channel
->ctx
, channel
->session
);
1138 old_ctx_error_free_old_param
:
1139 kfree(old_ucontext_param
);
1140 old_ctx_error_free_param
:
1141 kfree(ucontext_param
);
1145 case LTTNG_KERNEL_CONTEXT
:
1147 struct lttng_kernel_context ucontext_param
;
1149 if (copy_from_user(&ucontext_param
,
1150 (struct lttng_kernel_context __user
*) arg
,
1151 sizeof(ucontext_param
)))
1153 return lttng_abi_add_context(file
,
1155 &channel
->ctx
, channel
->session
);
1157 case LTTNG_KERNEL_OLD_ENABLE
:
1158 case LTTNG_KERNEL_ENABLE
:
1159 return lttng_channel_enable(channel
);
1160 case LTTNG_KERNEL_OLD_DISABLE
:
1161 case LTTNG_KERNEL_DISABLE
:
1162 return lttng_channel_disable(channel
);
1163 case LTTNG_KERNEL_SYSCALL_MASK
:
1164 return lttng_channel_syscall_mask(channel
,
1165 (struct lttng_kernel_syscall_mask __user
*) arg
);
1167 return -ENOIOCTLCMD
;
1173 * lttng_metadata_ioctl - lttng syscall through ioctl
1179 * This ioctl implements lttng commands:
1180 * LTTNG_KERNEL_STREAM
1181 * Returns an event stream file descriptor or failure.
1183 * Channel and event file descriptors also hold a reference on the session.
1186 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1189 case LTTNG_KERNEL_OLD_STREAM
:
1190 case LTTNG_KERNEL_STREAM
:
1191 return lttng_abi_open_metadata_stream(file
);
1193 return -ENOIOCTLCMD
;
1198 * lttng_channel_poll - lttng stream addition/removal monitoring
1203 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1205 struct lttng_channel
*channel
= file
->private_data
;
1206 unsigned int mask
= 0;
1208 if (file
->f_mode
& FMODE_READ
) {
1209 poll_wait_set_exclusive(wait
);
1210 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1213 if (channel
->ops
->is_disabled(channel
->chan
))
1215 if (channel
->ops
->is_finalized(channel
->chan
))
1217 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1218 return POLLIN
| POLLRDNORM
;
1226 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1228 struct lttng_channel
*channel
= file
->private_data
;
1231 fput(channel
->session
->file
);
1236 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1238 struct lttng_channel
*channel
= file
->private_data
;
1241 lttng_metadata_channel_destroy(channel
);
1242 fput(channel
->session
->file
);
1248 static const struct file_operations lttng_channel_fops
= {
1249 .owner
= THIS_MODULE
,
1250 .release
= lttng_channel_release
,
1251 .poll
= lttng_channel_poll
,
1252 .unlocked_ioctl
= lttng_channel_ioctl
,
1253 #ifdef CONFIG_COMPAT
1254 .compat_ioctl
= lttng_channel_ioctl
,
1258 static const struct file_operations lttng_metadata_fops
= {
1259 .owner
= THIS_MODULE
,
1260 .release
= lttng_metadata_channel_release
,
1261 .unlocked_ioctl
= lttng_metadata_ioctl
,
1262 #ifdef CONFIG_COMPAT
1263 .compat_ioctl
= lttng_metadata_ioctl
,
1268 * lttng_event_ioctl - lttng syscall through ioctl
1274 * This ioctl implements lttng commands:
1275 * LTTNG_KERNEL_CONTEXT
1276 * Prepend a context field to each record of this event
1277 * LTTNG_KERNEL_ENABLE
1278 * Enable recording for this event (weak enable)
1279 * LTTNG_KERNEL_DISABLE
1280 * Disable recording for this event (strong disable)
1283 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1285 struct lttng_event
*event
;
1286 struct lttng_enabler
*enabler
;
1287 enum lttng_event_type
*evtype
= file
->private_data
;
1290 case LTTNG_KERNEL_OLD_CONTEXT
:
1292 /* Not implemented */
1295 case LTTNG_KERNEL_CONTEXT
:
1297 /* Not implemented */
1300 case LTTNG_KERNEL_OLD_ENABLE
:
1301 case LTTNG_KERNEL_ENABLE
:
1303 case LTTNG_TYPE_EVENT
:
1304 event
= file
->private_data
;
1305 return lttng_event_enable(event
);
1306 case LTTNG_TYPE_ENABLER
:
1307 enabler
= file
->private_data
;
1308 return lttng_enabler_enable(enabler
);
1313 case LTTNG_KERNEL_OLD_DISABLE
:
1314 case LTTNG_KERNEL_DISABLE
:
1316 case LTTNG_TYPE_EVENT
:
1317 event
= file
->private_data
;
1318 return lttng_event_disable(event
);
1319 case LTTNG_TYPE_ENABLER
:
1320 enabler
= file
->private_data
;
1321 return lttng_enabler_disable(enabler
);
1326 case LTTNG_KERNEL_FILTER
:
1328 case LTTNG_TYPE_EVENT
:
1330 case LTTNG_TYPE_ENABLER
:
1332 enabler
= file
->private_data
;
1333 return lttng_enabler_attach_bytecode(enabler
,
1334 (struct lttng_kernel_filter_bytecode __user
*) arg
);
1339 return -ENOIOCTLCMD
;
1344 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1346 struct lttng_event
*event
;
1347 struct lttng_enabler
*enabler
;
1348 enum lttng_event_type
*evtype
= file
->private_data
;
1354 case LTTNG_TYPE_EVENT
:
1355 event
= file
->private_data
;
1357 fput(event
->chan
->file
);
1359 case LTTNG_TYPE_ENABLER
:
1360 enabler
= file
->private_data
;
1362 fput(enabler
->chan
->file
);
1372 /* TODO: filter control ioctl */
1373 static const struct file_operations lttng_event_fops
= {
1374 .owner
= THIS_MODULE
,
1375 .release
= lttng_event_release
,
1376 .unlocked_ioctl
= lttng_event_ioctl
,
1377 #ifdef CONFIG_COMPAT
1378 .compat_ioctl
= lttng_event_ioctl
,
1382 static int put_u64(uint64_t val
, unsigned long arg
)
1384 return put_user(val
, (uint64_t __user
*) arg
);
1387 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1388 unsigned int cmd
, unsigned long arg
)
1390 struct lib_ring_buffer
*buf
= filp
->private_data
;
1391 struct channel
*chan
= buf
->backend
.chan
;
1392 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1393 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1396 if (atomic_read(&chan
->record_disabled
))
1400 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1404 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1407 return put_u64(ts
, arg
);
1409 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1413 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1416 return put_u64(ts
, arg
);
1418 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1422 ret
= ops
->events_discarded(config
, buf
, &ed
);
1425 return put_u64(ed
, arg
);
1427 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1431 ret
= ops
->content_size(config
, buf
, &cs
);
1434 return put_u64(cs
, arg
);
1436 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1440 ret
= ops
->packet_size(config
, buf
, &ps
);
1443 return put_u64(ps
, arg
);
1445 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1449 ret
= ops
->stream_id(config
, buf
, &si
);
1452 return put_u64(si
, arg
);
1454 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1458 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1461 return put_u64(ts
, arg
);
1464 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1472 #ifdef CONFIG_COMPAT
1473 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1474 unsigned int cmd
, unsigned long arg
)
1476 struct lib_ring_buffer
*buf
= filp
->private_data
;
1477 struct channel
*chan
= buf
->backend
.chan
;
1478 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1479 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1482 if (atomic_read(&chan
->record_disabled
))
1486 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1490 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1493 return put_u64(ts
, arg
);
1495 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1499 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1502 return put_u64(ts
, arg
);
1504 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1508 ret
= ops
->events_discarded(config
, buf
, &ed
);
1511 return put_u64(ed
, arg
);
1513 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1517 ret
= ops
->content_size(config
, buf
, &cs
);
1520 return put_u64(cs
, arg
);
1522 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1526 ret
= ops
->packet_size(config
, buf
, &ps
);
1529 return put_u64(ps
, arg
);
1531 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1535 ret
= ops
->stream_id(config
, buf
, &si
);
1538 return put_u64(si
, arg
);
1540 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1544 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1547 return put_u64(ts
, arg
);
1550 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1557 #endif /* CONFIG_COMPAT */
1559 static void lttng_stream_override_ring_buffer_fops(void)
1561 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1562 lttng_stream_ring_buffer_file_operations
.open
=
1563 lib_ring_buffer_file_operations
.open
;
1564 lttng_stream_ring_buffer_file_operations
.release
=
1565 lib_ring_buffer_file_operations
.release
;
1566 lttng_stream_ring_buffer_file_operations
.poll
=
1567 lib_ring_buffer_file_operations
.poll
;
1568 lttng_stream_ring_buffer_file_operations
.splice_read
=
1569 lib_ring_buffer_file_operations
.splice_read
;
1570 lttng_stream_ring_buffer_file_operations
.mmap
=
1571 lib_ring_buffer_file_operations
.mmap
;
1572 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1573 lttng_stream_ring_buffer_ioctl
;
1574 lttng_stream_ring_buffer_file_operations
.llseek
=
1575 lib_ring_buffer_file_operations
.llseek
;
1576 #ifdef CONFIG_COMPAT
1577 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1578 lttng_stream_ring_buffer_compat_ioctl
;
1582 int __init
lttng_abi_init(void)
1586 wrapper_vmalloc_sync_all();
1587 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1590 if (!lttng_proc_dentry
) {
1591 printk(KERN_ERR
"Error creating LTTng control file\n");
1595 lttng_stream_override_ring_buffer_fops();
1601 /* No __exit annotation because used by init error path too. */
1602 void lttng_abi_exit(void)
1604 if (lttng_proc_dentry
)
1605 remove_proc_entry("lttng", NULL
);