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
427 * The returned channel will be deleted when its file descriptor is closed.
430 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
432 struct lttng_session
*session
= file
->private_data
;
435 case LTTNG_KERNEL_OLD_CHANNEL
:
437 struct lttng_kernel_channel chan_param
;
438 struct lttng_kernel_old_channel old_chan_param
;
440 if (copy_from_user(&old_chan_param
,
441 (struct lttng_kernel_old_channel __user
*) arg
,
442 sizeof(struct lttng_kernel_old_channel
)))
444 chan_param
.overwrite
= old_chan_param
.overwrite
;
445 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
446 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
447 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
448 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
449 chan_param
.output
= old_chan_param
.output
;
451 return lttng_abi_create_channel(file
, &chan_param
,
454 case LTTNG_KERNEL_CHANNEL
:
456 struct lttng_kernel_channel chan_param
;
458 if (copy_from_user(&chan_param
,
459 (struct lttng_kernel_channel __user
*) arg
,
460 sizeof(struct lttng_kernel_channel
)))
462 return lttng_abi_create_channel(file
, &chan_param
,
465 case LTTNG_KERNEL_OLD_SESSION_START
:
466 case LTTNG_KERNEL_OLD_ENABLE
:
467 case LTTNG_KERNEL_SESSION_START
:
468 case LTTNG_KERNEL_ENABLE
:
469 return lttng_session_enable(session
);
470 case LTTNG_KERNEL_OLD_SESSION_STOP
:
471 case LTTNG_KERNEL_OLD_DISABLE
:
472 case LTTNG_KERNEL_SESSION_STOP
:
473 case LTTNG_KERNEL_DISABLE
:
474 return lttng_session_disable(session
);
475 case LTTNG_KERNEL_OLD_METADATA
:
477 struct lttng_kernel_channel chan_param
;
478 struct lttng_kernel_old_channel old_chan_param
;
480 if (copy_from_user(&old_chan_param
,
481 (struct lttng_kernel_old_channel __user
*) arg
,
482 sizeof(struct lttng_kernel_old_channel
)))
484 chan_param
.overwrite
= old_chan_param
.overwrite
;
485 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
486 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
487 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
488 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
489 chan_param
.output
= old_chan_param
.output
;
491 return lttng_abi_create_channel(file
, &chan_param
,
494 case LTTNG_KERNEL_METADATA
:
496 struct lttng_kernel_channel chan_param
;
498 if (copy_from_user(&chan_param
,
499 (struct lttng_kernel_channel __user
*) arg
,
500 sizeof(struct lttng_kernel_channel
)))
502 return lttng_abi_create_channel(file
, &chan_param
,
511 * Called when the last file reference is dropped.
513 * Big fat note: channels and events are invariant for the whole session after
514 * their creation. So this session destruction also destroys all channel and
515 * event structures specific to this session (they are not destroyed when their
516 * individual file is released).
519 int lttng_session_release(struct inode
*inode
, struct file
*file
)
521 struct lttng_session
*session
= file
->private_data
;
524 lttng_session_destroy(session
);
528 static const struct file_operations lttng_session_fops
= {
529 .owner
= THIS_MODULE
,
530 .release
= lttng_session_release
,
531 .unlocked_ioctl
= lttng_session_ioctl
,
533 .compat_ioctl
= lttng_session_ioctl
,
538 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
542 * Handles the poll operations for the metadata channels.
545 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
548 struct lttng_metadata_stream
*stream
= filp
->private_data
;
549 struct lib_ring_buffer
*buf
= stream
->priv
;
551 unsigned int mask
= 0;
553 if (filp
->f_mode
& FMODE_READ
) {
554 poll_wait_set_exclusive(wait
);
555 poll_wait(filp
, &stream
->read_wait
, wait
);
557 finalized
= stream
->finalized
;
560 * lib_ring_buffer_is_finalized() contains a smp_rmb()
561 * ordering finalized load before offsets loads.
563 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
568 mutex_lock(&stream
->metadata_cache
->lock
);
569 if (stream
->metadata_cache
->metadata_written
>
570 stream
->metadata_out
)
572 mutex_unlock(&stream
->metadata_cache
->lock
);
579 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
580 unsigned int cmd
, unsigned long arg
)
582 struct lttng_metadata_stream
*stream
= filp
->private_data
;
584 stream
->metadata_out
= stream
->metadata_in
;
588 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
589 unsigned int cmd
, unsigned long arg
)
592 struct lttng_metadata_stream
*stream
= filp
->private_data
;
593 struct lib_ring_buffer
*buf
= stream
->priv
;
596 case RING_BUFFER_GET_NEXT_SUBBUF
:
598 struct lttng_metadata_stream
*stream
= filp
->private_data
;
599 struct lib_ring_buffer
*buf
= stream
->priv
;
600 struct channel
*chan
= buf
->backend
.chan
;
602 ret
= lttng_metadata_output_channel(stream
, chan
);
604 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
610 case RING_BUFFER_GET_SUBBUF
:
613 * Random access is not allowed for metadata channel.
617 case RING_BUFFER_FLUSH
:
619 struct lttng_metadata_stream
*stream
= filp
->private_data
;
620 struct lib_ring_buffer
*buf
= stream
->priv
;
621 struct channel
*chan
= buf
->backend
.chan
;
624 * Before doing the actual ring buffer flush, write up to one
625 * packet of metadata in the ring buffer.
627 ret
= lttng_metadata_output_channel(stream
, chan
);
632 case RING_BUFFER_SNAPSHOT
:
635 * Force the buffer to quiescent so the ring buffer
636 * don't attempt to perform a SWITCH_FLUSH, which would
637 * desynchronize the client accounting of the amount of
638 * data available in the buffer from the ring buffer
641 buf
->quiescent
= true;
647 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
649 /* Performing lib ring buffer ioctl after our own. */
650 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
655 case RING_BUFFER_PUT_NEXT_SUBBUF
:
657 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
670 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
671 unsigned int cmd
, unsigned long arg
)
674 struct lttng_metadata_stream
*stream
= filp
->private_data
;
675 struct lib_ring_buffer
*buf
= stream
->priv
;
678 case RING_BUFFER_GET_NEXT_SUBBUF
:
680 struct lttng_metadata_stream
*stream
= filp
->private_data
;
681 struct lib_ring_buffer
*buf
= stream
->priv
;
682 struct channel
*chan
= buf
->backend
.chan
;
684 ret
= lttng_metadata_output_channel(stream
, chan
);
686 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
692 case RING_BUFFER_GET_SUBBUF
:
695 * Random access is not allowed for metadata channel.
699 case RING_BUFFER_FLUSH
:
701 struct lttng_metadata_stream
*stream
= filp
->private_data
;
702 struct lib_ring_buffer
*buf
= stream
->priv
;
703 struct channel
*chan
= buf
->backend
.chan
;
706 * Before doing the actual ring buffer flush, write up to one
707 * packet of metadata in the ring buffer.
709 ret
= lttng_metadata_output_channel(stream
, chan
);
714 case RING_BUFFER_SNAPSHOT
:
717 * Force the buffer to quiescent so the ring buffer
718 * don't attempt to perform a SWITCH_FLUSH, which would
719 * desynchronize the client accounting of the amount of
720 * data available in the buffer from the ring buffer
723 buf
->quiescent
= true;
729 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
731 /* Performing lib ring buffer ioctl after our own. */
732 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
737 case RING_BUFFER_PUT_NEXT_SUBBUF
:
739 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
752 * This is not used by anonymous file descriptors. This code is left
753 * there if we ever want to implement an inode with open() operation.
756 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
758 struct lttng_metadata_stream
*stream
= inode
->i_private
;
759 struct lib_ring_buffer
*buf
= stream
->priv
;
761 file
->private_data
= buf
;
763 * Since life-time of metadata cache differs from that of
764 * session, we need to keep our own reference on the transport.
766 if (!try_module_get(stream
->transport
->owner
)) {
767 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
770 return lib_ring_buffer_open(inode
, file
, buf
);
774 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
776 struct lttng_metadata_stream
*stream
= file
->private_data
;
777 struct lib_ring_buffer
*buf
= stream
->priv
;
779 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
780 module_put(stream
->transport
->owner
);
781 return lib_ring_buffer_release(inode
, file
, buf
);
785 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
786 struct pipe_inode_info
*pipe
, size_t len
,
789 struct lttng_metadata_stream
*stream
= in
->private_data
;
790 struct lib_ring_buffer
*buf
= stream
->priv
;
792 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
797 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
798 struct vm_area_struct
*vma
)
800 struct lttng_metadata_stream
*stream
= filp
->private_data
;
801 struct lib_ring_buffer
*buf
= stream
->priv
;
803 return lib_ring_buffer_mmap(filp
, vma
, buf
);
807 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
808 .owner
= THIS_MODULE
,
809 .open
= lttng_metadata_ring_buffer_open
,
810 .release
= lttng_metadata_ring_buffer_release
,
811 .poll
= lttng_metadata_ring_buffer_poll
,
812 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
813 .mmap
= lttng_metadata_ring_buffer_mmap
,
814 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
815 .llseek
= vfs_lib_ring_buffer_no_llseek
,
817 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
822 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
823 const struct file_operations
*fops
)
826 struct file
*stream_file
;
828 stream_fd
= lttng_get_unused_fd();
833 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
834 stream_priv
, O_RDWR
);
835 if (IS_ERR(stream_file
)) {
836 ret
= PTR_ERR(stream_file
);
840 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
841 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
842 * file descriptor, so we set FMODE_PREAD here.
844 stream_file
->f_mode
|= FMODE_PREAD
;
845 fd_install(stream_fd
, stream_file
);
847 * The stream holds a reference to the channel within the generic ring
848 * buffer library, so no need to hold a refcount on the channel and
849 * session files here.
854 put_unused_fd(stream_fd
);
860 int lttng_abi_open_stream(struct file
*channel_file
)
862 struct lttng_channel
*channel
= channel_file
->private_data
;
863 struct lib_ring_buffer
*buf
;
867 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
872 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
873 <tng_stream_ring_buffer_file_operations
);
880 channel
->ops
->buffer_read_close(buf
);
885 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
887 struct lttng_channel
*channel
= channel_file
->private_data
;
888 struct lttng_session
*session
= channel
->session
;
889 struct lib_ring_buffer
*buf
;
891 struct lttng_metadata_stream
*metadata_stream
;
894 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
898 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
900 if (!metadata_stream
) {
904 metadata_stream
->metadata_cache
= session
->metadata_cache
;
905 init_waitqueue_head(&metadata_stream
->read_wait
);
906 metadata_stream
->priv
= buf
;
907 stream_priv
= metadata_stream
;
908 metadata_stream
->transport
= channel
->transport
;
911 * Since life-time of metadata cache differs from that of
912 * session, we need to keep our own reference on the transport.
914 if (!try_module_get(metadata_stream
->transport
->owner
)) {
915 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
920 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
921 <tng_metadata_ring_buffer_file_operations
);
925 kref_get(&session
->metadata_cache
->refcount
);
926 list_add(&metadata_stream
->list
,
927 &session
->metadata_cache
->metadata_stream
);
931 module_put(metadata_stream
->transport
->owner
);
933 kfree(metadata_stream
);
935 channel
->ops
->buffer_read_close(buf
);
940 int lttng_abi_create_event(struct file
*channel_file
,
941 struct lttng_kernel_event
*event_param
)
943 struct lttng_channel
*channel
= channel_file
->private_data
;
944 struct lttng_event
*event
;
946 struct file
*event_file
;
948 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
949 switch (event_param
->instrumentation
) {
950 case LTTNG_KERNEL_KRETPROBE
:
951 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
953 case LTTNG_KERNEL_KPROBE
:
954 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
956 case LTTNG_KERNEL_FUNCTION
:
957 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
962 switch (event_param
->instrumentation
) {
964 event_fd
= lttng_get_unused_fd();
969 event_file
= anon_inode_getfile("[lttng_event]",
972 if (IS_ERR(event_file
)) {
973 ret
= PTR_ERR(event_file
);
977 * We tolerate no failure path after event creation. It
978 * will stay invariant for the rest of the session.
980 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
981 WARN_ON_ONCE(!event
);
983 ret
= PTR_ERR(event
);
986 event_file
->private_data
= event
;
987 fd_install(event_fd
, event_file
);
988 /* The event holds a reference on the channel */
989 atomic_long_inc(&channel_file
->f_count
);
991 case LTTNG_KERNEL_SYSCALL
:
992 ret
= lttng_syscalls_register(channel
, NULL
);
996 if (event_param
->u
.syscall
.enable
) {
997 ret
= lttng_syscall_filter_enable(channel
,
998 event_param
->name
[0] == '\0' ?
999 NULL
: event_param
->name
);
1004 ret
= lttng_syscall_filter_disable(channel
,
1005 event_param
->name
[0] == '\0' ?
1006 NULL
: event_param
->name
);
1017 put_unused_fd(event_fd
);
1023 * lttng_channel_ioctl - lttng syscall through ioctl
1029 * This ioctl implements lttng commands:
1030 * LTTNG_KERNEL_STREAM
1031 * Returns an event stream file descriptor or failure.
1032 * (typically, one event stream records events from one CPU)
1033 * LTTNG_KERNEL_EVENT
1034 * Returns an event file descriptor or failure.
1035 * LTTNG_KERNEL_CONTEXT
1036 * Prepend a context field to each event in the channel
1037 * LTTNG_KERNEL_ENABLE
1038 * Enable recording for events in this channel (weak enable)
1039 * LTTNG_KERNEL_DISABLE
1040 * Disable recording for events in this channel (strong disable)
1042 * Channel and event file descriptors also hold a reference on the session.
1045 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1047 struct lttng_channel
*channel
= file
->private_data
;
1050 case LTTNG_KERNEL_OLD_STREAM
:
1051 case LTTNG_KERNEL_STREAM
:
1052 return lttng_abi_open_stream(file
);
1053 case LTTNG_KERNEL_OLD_EVENT
:
1055 struct lttng_kernel_event
*uevent_param
;
1056 struct lttng_kernel_old_event
*old_uevent_param
;
1059 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1061 if (!uevent_param
) {
1065 old_uevent_param
= kmalloc(
1066 sizeof(struct lttng_kernel_old_event
),
1068 if (!old_uevent_param
) {
1070 goto old_event_error_free_param
;
1072 if (copy_from_user(old_uevent_param
,
1073 (struct lttng_kernel_old_event __user
*) arg
,
1074 sizeof(struct lttng_kernel_old_event
))) {
1076 goto old_event_error_free_old_param
;
1079 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1080 sizeof(uevent_param
->name
));
1081 uevent_param
->instrumentation
=
1082 old_uevent_param
->instrumentation
;
1084 switch (old_uevent_param
->instrumentation
) {
1085 case LTTNG_KERNEL_KPROBE
:
1086 uevent_param
->u
.kprobe
.addr
=
1087 old_uevent_param
->u
.kprobe
.addr
;
1088 uevent_param
->u
.kprobe
.offset
=
1089 old_uevent_param
->u
.kprobe
.offset
;
1090 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1091 old_uevent_param
->u
.kprobe
.symbol_name
,
1092 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1094 case LTTNG_KERNEL_KRETPROBE
:
1095 uevent_param
->u
.kretprobe
.addr
=
1096 old_uevent_param
->u
.kretprobe
.addr
;
1097 uevent_param
->u
.kretprobe
.offset
=
1098 old_uevent_param
->u
.kretprobe
.offset
;
1099 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1100 old_uevent_param
->u
.kretprobe
.symbol_name
,
1101 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1103 case LTTNG_KERNEL_FUNCTION
:
1104 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1105 old_uevent_param
->u
.ftrace
.symbol_name
,
1106 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1111 ret
= lttng_abi_create_event(file
, uevent_param
);
1113 old_event_error_free_old_param
:
1114 kfree(old_uevent_param
);
1115 old_event_error_free_param
:
1116 kfree(uevent_param
);
1120 case LTTNG_KERNEL_EVENT
:
1122 struct lttng_kernel_event uevent_param
;
1124 if (copy_from_user(&uevent_param
,
1125 (struct lttng_kernel_event __user
*) arg
,
1126 sizeof(uevent_param
)))
1128 return lttng_abi_create_event(file
, &uevent_param
);
1130 case LTTNG_KERNEL_OLD_CONTEXT
:
1132 struct lttng_kernel_context
*ucontext_param
;
1133 struct lttng_kernel_old_context
*old_ucontext_param
;
1136 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1138 if (!ucontext_param
) {
1142 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1144 if (!old_ucontext_param
) {
1146 goto old_ctx_error_free_param
;
1149 if (copy_from_user(old_ucontext_param
,
1150 (struct lttng_kernel_old_context __user
*) arg
,
1151 sizeof(struct lttng_kernel_old_context
))) {
1153 goto old_ctx_error_free_old_param
;
1155 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1156 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1157 sizeof(ucontext_param
->padding
));
1158 /* only type that uses the union */
1159 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1160 ucontext_param
->u
.perf_counter
.type
=
1161 old_ucontext_param
->u
.perf_counter
.type
;
1162 ucontext_param
->u
.perf_counter
.config
=
1163 old_ucontext_param
->u
.perf_counter
.config
;
1164 memcpy(ucontext_param
->u
.perf_counter
.name
,
1165 old_ucontext_param
->u
.perf_counter
.name
,
1166 sizeof(ucontext_param
->u
.perf_counter
.name
));
1169 ret
= lttng_abi_add_context(file
,
1171 &channel
->ctx
, channel
->session
);
1173 old_ctx_error_free_old_param
:
1174 kfree(old_ucontext_param
);
1175 old_ctx_error_free_param
:
1176 kfree(ucontext_param
);
1180 case LTTNG_KERNEL_CONTEXT
:
1182 struct lttng_kernel_context ucontext_param
;
1184 if (copy_from_user(&ucontext_param
,
1185 (struct lttng_kernel_context __user
*) arg
,
1186 sizeof(ucontext_param
)))
1188 return lttng_abi_add_context(file
,
1190 &channel
->ctx
, channel
->session
);
1192 case LTTNG_KERNEL_OLD_ENABLE
:
1193 case LTTNG_KERNEL_ENABLE
:
1194 return lttng_channel_enable(channel
);
1195 case LTTNG_KERNEL_OLD_DISABLE
:
1196 case LTTNG_KERNEL_DISABLE
:
1197 return lttng_channel_disable(channel
);
1198 case LTTNG_KERNEL_SYSCALL_MASK
:
1199 return lttng_channel_syscall_mask(channel
,
1200 (struct lttng_kernel_syscall_mask __user
*) arg
);
1202 return -ENOIOCTLCMD
;
1208 * lttng_metadata_ioctl - lttng syscall through ioctl
1214 * This ioctl implements lttng commands:
1215 * LTTNG_KERNEL_STREAM
1216 * Returns an event stream file descriptor or failure.
1218 * Channel and event file descriptors also hold a reference on the session.
1221 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1224 case LTTNG_KERNEL_OLD_STREAM
:
1225 case LTTNG_KERNEL_STREAM
:
1226 return lttng_abi_open_metadata_stream(file
);
1228 return -ENOIOCTLCMD
;
1233 * lttng_channel_poll - lttng stream addition/removal monitoring
1238 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1240 struct lttng_channel
*channel
= file
->private_data
;
1241 unsigned int mask
= 0;
1243 if (file
->f_mode
& FMODE_READ
) {
1244 poll_wait_set_exclusive(wait
);
1245 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1248 if (channel
->ops
->is_disabled(channel
->chan
))
1250 if (channel
->ops
->is_finalized(channel
->chan
))
1252 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1253 return POLLIN
| POLLRDNORM
;
1261 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1263 struct lttng_channel
*channel
= file
->private_data
;
1266 fput(channel
->session
->file
);
1271 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1273 struct lttng_channel
*channel
= file
->private_data
;
1276 fput(channel
->session
->file
);
1277 lttng_metadata_channel_destroy(channel
);
1283 static const struct file_operations lttng_channel_fops
= {
1284 .owner
= THIS_MODULE
,
1285 .release
= lttng_channel_release
,
1286 .poll
= lttng_channel_poll
,
1287 .unlocked_ioctl
= lttng_channel_ioctl
,
1288 #ifdef CONFIG_COMPAT
1289 .compat_ioctl
= lttng_channel_ioctl
,
1293 static const struct file_operations lttng_metadata_fops
= {
1294 .owner
= THIS_MODULE
,
1295 .release
= lttng_metadata_channel_release
,
1296 .unlocked_ioctl
= lttng_metadata_ioctl
,
1297 #ifdef CONFIG_COMPAT
1298 .compat_ioctl
= lttng_metadata_ioctl
,
1303 * lttng_event_ioctl - lttng syscall through ioctl
1309 * This ioctl implements lttng commands:
1310 * LTTNG_KERNEL_CONTEXT
1311 * Prepend a context field to each record of this event
1312 * LTTNG_KERNEL_ENABLE
1313 * Enable recording for this event (weak enable)
1314 * LTTNG_KERNEL_DISABLE
1315 * Disable recording for this event (strong disable)
1318 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1320 struct lttng_event
*event
= file
->private_data
;
1323 case LTTNG_KERNEL_OLD_CONTEXT
:
1325 struct lttng_kernel_context
*ucontext_param
;
1326 struct lttng_kernel_old_context
*old_ucontext_param
;
1329 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1331 if (!ucontext_param
) {
1335 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1337 if (!old_ucontext_param
) {
1339 goto old_ctx_error_free_param
;
1342 if (copy_from_user(old_ucontext_param
,
1343 (struct lttng_kernel_old_context __user
*) arg
,
1344 sizeof(struct lttng_kernel_old_context
))) {
1346 goto old_ctx_error_free_old_param
;
1348 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1349 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1350 sizeof(ucontext_param
->padding
));
1351 /* only type that uses the union */
1352 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1353 ucontext_param
->u
.perf_counter
.type
=
1354 old_ucontext_param
->u
.perf_counter
.type
;
1355 ucontext_param
->u
.perf_counter
.config
=
1356 old_ucontext_param
->u
.perf_counter
.config
;
1357 memcpy(ucontext_param
->u
.perf_counter
.name
,
1358 old_ucontext_param
->u
.perf_counter
.name
,
1359 sizeof(ucontext_param
->u
.perf_counter
.name
));
1362 ret
= lttng_abi_add_context(file
,
1364 &event
->ctx
, event
->chan
->session
);
1366 old_ctx_error_free_old_param
:
1367 kfree(old_ucontext_param
);
1368 old_ctx_error_free_param
:
1369 kfree(ucontext_param
);
1373 case LTTNG_KERNEL_CONTEXT
:
1375 struct lttng_kernel_context ucontext_param
;
1377 if (copy_from_user(&ucontext_param
,
1378 (struct lttng_kernel_context __user
*) arg
,
1379 sizeof(ucontext_param
)))
1381 return lttng_abi_add_context(file
,
1383 &event
->ctx
, event
->chan
->session
);
1385 case LTTNG_KERNEL_OLD_ENABLE
:
1386 case LTTNG_KERNEL_ENABLE
:
1387 return lttng_event_enable(event
);
1388 case LTTNG_KERNEL_OLD_DISABLE
:
1389 case LTTNG_KERNEL_DISABLE
:
1390 return lttng_event_disable(event
);
1392 return -ENOIOCTLCMD
;
1397 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1399 struct lttng_event
*event
= file
->private_data
;
1402 fput(event
->chan
->file
);
1406 /* TODO: filter control ioctl */
1407 static const struct file_operations lttng_event_fops
= {
1408 .owner
= THIS_MODULE
,
1409 .release
= lttng_event_release
,
1410 .unlocked_ioctl
= lttng_event_ioctl
,
1411 #ifdef CONFIG_COMPAT
1412 .compat_ioctl
= lttng_event_ioctl
,
1416 static int put_u64(uint64_t val
, unsigned long arg
)
1418 return put_user(val
, (uint64_t __user
*) arg
);
1421 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1422 unsigned int cmd
, unsigned long arg
)
1424 struct lib_ring_buffer
*buf
= filp
->private_data
;
1425 struct channel
*chan
= buf
->backend
.chan
;
1426 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1427 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1430 if (atomic_read(&chan
->record_disabled
))
1434 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1438 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1441 return put_u64(ts
, arg
);
1443 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1447 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1450 return put_u64(ts
, arg
);
1452 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1456 ret
= ops
->events_discarded(config
, buf
, &ed
);
1459 return put_u64(ed
, arg
);
1461 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1465 ret
= ops
->content_size(config
, buf
, &cs
);
1468 return put_u64(cs
, arg
);
1470 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1474 ret
= ops
->packet_size(config
, buf
, &ps
);
1477 return put_u64(ps
, arg
);
1479 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1483 ret
= ops
->stream_id(config
, buf
, &si
);
1486 return put_u64(si
, arg
);
1488 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1492 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1495 return put_u64(ts
, arg
);
1498 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1506 #ifdef CONFIG_COMPAT
1507 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1508 unsigned int cmd
, unsigned long arg
)
1510 struct lib_ring_buffer
*buf
= filp
->private_data
;
1511 struct channel
*chan
= buf
->backend
.chan
;
1512 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1513 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1516 if (atomic_read(&chan
->record_disabled
))
1520 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1524 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1527 return put_u64(ts
, arg
);
1529 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1533 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1536 return put_u64(ts
, arg
);
1538 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1542 ret
= ops
->events_discarded(config
, buf
, &ed
);
1545 return put_u64(ed
, arg
);
1547 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1551 ret
= ops
->content_size(config
, buf
, &cs
);
1554 return put_u64(cs
, arg
);
1556 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1560 ret
= ops
->packet_size(config
, buf
, &ps
);
1563 return put_u64(ps
, arg
);
1565 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1569 ret
= ops
->stream_id(config
, buf
, &si
);
1572 return put_u64(si
, arg
);
1574 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1578 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1581 return put_u64(ts
, arg
);
1584 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1591 #endif /* CONFIG_COMPAT */
1593 static void lttng_stream_override_ring_buffer_fops(void)
1595 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1596 lttng_stream_ring_buffer_file_operations
.open
=
1597 lib_ring_buffer_file_operations
.open
;
1598 lttng_stream_ring_buffer_file_operations
.release
=
1599 lib_ring_buffer_file_operations
.release
;
1600 lttng_stream_ring_buffer_file_operations
.poll
=
1601 lib_ring_buffer_file_operations
.poll
;
1602 lttng_stream_ring_buffer_file_operations
.splice_read
=
1603 lib_ring_buffer_file_operations
.splice_read
;
1604 lttng_stream_ring_buffer_file_operations
.mmap
=
1605 lib_ring_buffer_file_operations
.mmap
;
1606 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1607 lttng_stream_ring_buffer_ioctl
;
1608 lttng_stream_ring_buffer_file_operations
.llseek
=
1609 lib_ring_buffer_file_operations
.llseek
;
1610 #ifdef CONFIG_COMPAT
1611 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1612 lttng_stream_ring_buffer_compat_ioctl
;
1616 int __init
lttng_abi_init(void)
1620 wrapper_vmalloc_sync_all();
1621 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1624 if (!lttng_proc_dentry
) {
1625 printk(KERN_ERR
"Error creating LTTng control file\n");
1629 lttng_stream_override_ring_buffer_fops();
1635 /* No __exit annotation because used by init error path too. */
1636 void lttng_abi_exit(void)
1638 if (lttng_proc_dentry
)
1639 remove_proc_entry("lttng", NULL
);