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
);
635 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
637 /* Performing lib ring buffer ioctl after our own. */
638 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
643 case RING_BUFFER_PUT_NEXT_SUBBUF
:
645 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
658 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
659 unsigned int cmd
, unsigned long arg
)
662 struct lttng_metadata_stream
*stream
= filp
->private_data
;
663 struct lib_ring_buffer
*buf
= stream
->priv
;
666 case RING_BUFFER_GET_NEXT_SUBBUF
:
668 struct lttng_metadata_stream
*stream
= filp
->private_data
;
669 struct lib_ring_buffer
*buf
= stream
->priv
;
670 struct channel
*chan
= buf
->backend
.chan
;
672 ret
= lttng_metadata_output_channel(stream
, chan
);
674 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
680 case RING_BUFFER_GET_SUBBUF
:
683 * Random access is not allowed for metadata channel.
687 case RING_BUFFER_FLUSH
:
689 struct lttng_metadata_stream
*stream
= filp
->private_data
;
690 struct lib_ring_buffer
*buf
= stream
->priv
;
691 struct channel
*chan
= buf
->backend
.chan
;
694 * Before doing the actual ring buffer flush, write up to one
695 * packet of metadata in the ring buffer.
697 ret
= lttng_metadata_output_channel(stream
, chan
);
705 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
707 /* Performing lib ring buffer ioctl after our own. */
708 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
713 case RING_BUFFER_PUT_NEXT_SUBBUF
:
715 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
728 * This is not used by anonymous file descriptors. This code is left
729 * there if we ever want to implement an inode with open() operation.
732 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
734 struct lttng_metadata_stream
*stream
= inode
->i_private
;
735 struct lib_ring_buffer
*buf
= stream
->priv
;
737 file
->private_data
= buf
;
739 * Since life-time of metadata cache differs from that of
740 * session, we need to keep our own reference on the transport.
742 if (!try_module_get(stream
->transport
->owner
)) {
743 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
746 return lib_ring_buffer_open(inode
, file
, buf
);
750 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
752 struct lttng_metadata_stream
*stream
= file
->private_data
;
753 struct lib_ring_buffer
*buf
= stream
->priv
;
755 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
756 module_put(stream
->transport
->owner
);
757 return lib_ring_buffer_release(inode
, file
, buf
);
761 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
762 struct pipe_inode_info
*pipe
, size_t len
,
765 struct lttng_metadata_stream
*stream
= in
->private_data
;
766 struct lib_ring_buffer
*buf
= stream
->priv
;
768 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
773 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
774 struct vm_area_struct
*vma
)
776 struct lttng_metadata_stream
*stream
= filp
->private_data
;
777 struct lib_ring_buffer
*buf
= stream
->priv
;
779 return lib_ring_buffer_mmap(filp
, vma
, buf
);
783 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
784 .owner
= THIS_MODULE
,
785 .open
= lttng_metadata_ring_buffer_open
,
786 .release
= lttng_metadata_ring_buffer_release
,
787 .poll
= lttng_metadata_ring_buffer_poll
,
788 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
789 .mmap
= lttng_metadata_ring_buffer_mmap
,
790 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
791 .llseek
= vfs_lib_ring_buffer_no_llseek
,
793 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
798 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
799 const struct file_operations
*fops
)
802 struct file
*stream_file
;
804 stream_fd
= lttng_get_unused_fd();
809 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
810 stream_priv
, O_RDWR
);
811 if (IS_ERR(stream_file
)) {
812 ret
= PTR_ERR(stream_file
);
816 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
817 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
818 * file descriptor, so we set FMODE_PREAD here.
820 stream_file
->f_mode
|= FMODE_PREAD
;
821 fd_install(stream_fd
, stream_file
);
823 * The stream holds a reference to the channel within the generic ring
824 * buffer library, so no need to hold a refcount on the channel and
825 * session files here.
830 put_unused_fd(stream_fd
);
836 int lttng_abi_open_stream(struct file
*channel_file
)
838 struct lttng_channel
*channel
= channel_file
->private_data
;
839 struct lib_ring_buffer
*buf
;
843 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
848 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
849 <tng_stream_ring_buffer_file_operations
);
856 channel
->ops
->buffer_read_close(buf
);
861 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
863 struct lttng_channel
*channel
= channel_file
->private_data
;
864 struct lttng_session
*session
= channel
->session
;
865 struct lib_ring_buffer
*buf
;
867 struct lttng_metadata_stream
*metadata_stream
;
870 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
874 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
876 if (!metadata_stream
) {
880 metadata_stream
->metadata_cache
= session
->metadata_cache
;
881 init_waitqueue_head(&metadata_stream
->read_wait
);
882 metadata_stream
->priv
= buf
;
883 stream_priv
= metadata_stream
;
884 metadata_stream
->transport
= channel
->transport
;
887 * Since life-time of metadata cache differs from that of
888 * session, we need to keep our own reference on the transport.
890 if (!try_module_get(metadata_stream
->transport
->owner
)) {
891 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
896 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
897 <tng_metadata_ring_buffer_file_operations
);
901 kref_get(&session
->metadata_cache
->refcount
);
902 list_add(&metadata_stream
->list
,
903 &session
->metadata_cache
->metadata_stream
);
907 module_put(metadata_stream
->transport
->owner
);
909 kfree(metadata_stream
);
911 channel
->ops
->buffer_read_close(buf
);
916 int lttng_abi_create_event(struct file
*channel_file
,
917 struct lttng_kernel_event
*event_param
)
919 struct lttng_channel
*channel
= channel_file
->private_data
;
920 struct lttng_event
*event
;
922 struct file
*event_file
;
924 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
925 switch (event_param
->instrumentation
) {
926 case LTTNG_KERNEL_KRETPROBE
:
927 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
929 case LTTNG_KERNEL_KPROBE
:
930 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
932 case LTTNG_KERNEL_FUNCTION
:
933 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
938 switch (event_param
->instrumentation
) {
940 event_fd
= lttng_get_unused_fd();
945 event_file
= anon_inode_getfile("[lttng_event]",
948 if (IS_ERR(event_file
)) {
949 ret
= PTR_ERR(event_file
);
953 * We tolerate no failure path after event creation. It
954 * will stay invariant for the rest of the session.
956 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
957 WARN_ON_ONCE(!event
);
959 ret
= PTR_ERR(event
);
962 event_file
->private_data
= event
;
963 fd_install(event_fd
, event_file
);
964 /* The event holds a reference on the channel */
965 atomic_long_inc(&channel_file
->f_count
);
967 case LTTNG_KERNEL_SYSCALL
:
968 ret
= lttng_syscalls_register(channel
, NULL
);
972 if (event_param
->u
.syscall
.enable
) {
973 ret
= lttng_syscall_filter_enable(channel
,
974 event_param
->name
[0] == '\0' ?
975 NULL
: event_param
->name
);
980 ret
= lttng_syscall_filter_disable(channel
,
981 event_param
->name
[0] == '\0' ?
982 NULL
: event_param
->name
);
993 put_unused_fd(event_fd
);
999 * lttng_channel_ioctl - lttng syscall through ioctl
1005 * This ioctl implements lttng commands:
1006 * LTTNG_KERNEL_STREAM
1007 * Returns an event stream file descriptor or failure.
1008 * (typically, one event stream records events from one CPU)
1009 * LTTNG_KERNEL_EVENT
1010 * Returns an event file descriptor or failure.
1011 * LTTNG_KERNEL_CONTEXT
1012 * Prepend a context field to each event in the channel
1013 * LTTNG_KERNEL_ENABLE
1014 * Enable recording for events in this channel (weak enable)
1015 * LTTNG_KERNEL_DISABLE
1016 * Disable recording for events in this channel (strong disable)
1018 * Channel and event file descriptors also hold a reference on the session.
1021 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1023 struct lttng_channel
*channel
= file
->private_data
;
1026 case LTTNG_KERNEL_OLD_STREAM
:
1027 case LTTNG_KERNEL_STREAM
:
1028 return lttng_abi_open_stream(file
);
1029 case LTTNG_KERNEL_OLD_EVENT
:
1031 struct lttng_kernel_event
*uevent_param
;
1032 struct lttng_kernel_old_event
*old_uevent_param
;
1035 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1037 if (!uevent_param
) {
1041 old_uevent_param
= kmalloc(
1042 sizeof(struct lttng_kernel_old_event
),
1044 if (!old_uevent_param
) {
1046 goto old_event_error_free_param
;
1048 if (copy_from_user(old_uevent_param
,
1049 (struct lttng_kernel_old_event __user
*) arg
,
1050 sizeof(struct lttng_kernel_old_event
))) {
1052 goto old_event_error_free_old_param
;
1055 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1056 sizeof(uevent_param
->name
));
1057 uevent_param
->instrumentation
=
1058 old_uevent_param
->instrumentation
;
1060 switch (old_uevent_param
->instrumentation
) {
1061 case LTTNG_KERNEL_KPROBE
:
1062 uevent_param
->u
.kprobe
.addr
=
1063 old_uevent_param
->u
.kprobe
.addr
;
1064 uevent_param
->u
.kprobe
.offset
=
1065 old_uevent_param
->u
.kprobe
.offset
;
1066 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1067 old_uevent_param
->u
.kprobe
.symbol_name
,
1068 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1070 case LTTNG_KERNEL_KRETPROBE
:
1071 uevent_param
->u
.kretprobe
.addr
=
1072 old_uevent_param
->u
.kretprobe
.addr
;
1073 uevent_param
->u
.kretprobe
.offset
=
1074 old_uevent_param
->u
.kretprobe
.offset
;
1075 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1076 old_uevent_param
->u
.kretprobe
.symbol_name
,
1077 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1079 case LTTNG_KERNEL_FUNCTION
:
1080 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1081 old_uevent_param
->u
.ftrace
.symbol_name
,
1082 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1087 ret
= lttng_abi_create_event(file
, uevent_param
);
1089 old_event_error_free_old_param
:
1090 kfree(old_uevent_param
);
1091 old_event_error_free_param
:
1092 kfree(uevent_param
);
1096 case LTTNG_KERNEL_EVENT
:
1098 struct lttng_kernel_event uevent_param
;
1100 if (copy_from_user(&uevent_param
,
1101 (struct lttng_kernel_event __user
*) arg
,
1102 sizeof(uevent_param
)))
1104 return lttng_abi_create_event(file
, &uevent_param
);
1106 case LTTNG_KERNEL_OLD_CONTEXT
:
1108 struct lttng_kernel_context
*ucontext_param
;
1109 struct lttng_kernel_old_context
*old_ucontext_param
;
1112 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1114 if (!ucontext_param
) {
1118 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1120 if (!old_ucontext_param
) {
1122 goto old_ctx_error_free_param
;
1125 if (copy_from_user(old_ucontext_param
,
1126 (struct lttng_kernel_old_context __user
*) arg
,
1127 sizeof(struct lttng_kernel_old_context
))) {
1129 goto old_ctx_error_free_old_param
;
1131 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1132 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1133 sizeof(ucontext_param
->padding
));
1134 /* only type that uses the union */
1135 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1136 ucontext_param
->u
.perf_counter
.type
=
1137 old_ucontext_param
->u
.perf_counter
.type
;
1138 ucontext_param
->u
.perf_counter
.config
=
1139 old_ucontext_param
->u
.perf_counter
.config
;
1140 memcpy(ucontext_param
->u
.perf_counter
.name
,
1141 old_ucontext_param
->u
.perf_counter
.name
,
1142 sizeof(ucontext_param
->u
.perf_counter
.name
));
1145 ret
= lttng_abi_add_context(file
,
1147 &channel
->ctx
, channel
->session
);
1149 old_ctx_error_free_old_param
:
1150 kfree(old_ucontext_param
);
1151 old_ctx_error_free_param
:
1152 kfree(ucontext_param
);
1156 case LTTNG_KERNEL_CONTEXT
:
1158 struct lttng_kernel_context ucontext_param
;
1160 if (copy_from_user(&ucontext_param
,
1161 (struct lttng_kernel_context __user
*) arg
,
1162 sizeof(ucontext_param
)))
1164 return lttng_abi_add_context(file
,
1166 &channel
->ctx
, channel
->session
);
1168 case LTTNG_KERNEL_OLD_ENABLE
:
1169 case LTTNG_KERNEL_ENABLE
:
1170 return lttng_channel_enable(channel
);
1171 case LTTNG_KERNEL_OLD_DISABLE
:
1172 case LTTNG_KERNEL_DISABLE
:
1173 return lttng_channel_disable(channel
);
1174 case LTTNG_KERNEL_SYSCALL_MASK
:
1175 return lttng_channel_syscall_mask(channel
,
1176 (struct lttng_kernel_syscall_mask __user
*) arg
);
1178 return -ENOIOCTLCMD
;
1184 * lttng_metadata_ioctl - lttng syscall through ioctl
1190 * This ioctl implements lttng commands:
1191 * LTTNG_KERNEL_STREAM
1192 * Returns an event stream file descriptor or failure.
1194 * Channel and event file descriptors also hold a reference on the session.
1197 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1200 case LTTNG_KERNEL_OLD_STREAM
:
1201 case LTTNG_KERNEL_STREAM
:
1202 return lttng_abi_open_metadata_stream(file
);
1204 return -ENOIOCTLCMD
;
1209 * lttng_channel_poll - lttng stream addition/removal monitoring
1214 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1216 struct lttng_channel
*channel
= file
->private_data
;
1217 unsigned int mask
= 0;
1219 if (file
->f_mode
& FMODE_READ
) {
1220 poll_wait_set_exclusive(wait
);
1221 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1224 if (channel
->ops
->is_disabled(channel
->chan
))
1226 if (channel
->ops
->is_finalized(channel
->chan
))
1228 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1229 return POLLIN
| POLLRDNORM
;
1237 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1239 struct lttng_channel
*channel
= file
->private_data
;
1242 fput(channel
->session
->file
);
1247 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1249 struct lttng_channel
*channel
= file
->private_data
;
1252 fput(channel
->session
->file
);
1253 lttng_metadata_channel_destroy(channel
);
1259 static const struct file_operations lttng_channel_fops
= {
1260 .owner
= THIS_MODULE
,
1261 .release
= lttng_channel_release
,
1262 .poll
= lttng_channel_poll
,
1263 .unlocked_ioctl
= lttng_channel_ioctl
,
1264 #ifdef CONFIG_COMPAT
1265 .compat_ioctl
= lttng_channel_ioctl
,
1269 static const struct file_operations lttng_metadata_fops
= {
1270 .owner
= THIS_MODULE
,
1271 .release
= lttng_metadata_channel_release
,
1272 .unlocked_ioctl
= lttng_metadata_ioctl
,
1273 #ifdef CONFIG_COMPAT
1274 .compat_ioctl
= lttng_metadata_ioctl
,
1279 * lttng_event_ioctl - lttng syscall through ioctl
1285 * This ioctl implements lttng commands:
1286 * LTTNG_KERNEL_CONTEXT
1287 * Prepend a context field to each record of this event
1288 * LTTNG_KERNEL_ENABLE
1289 * Enable recording for this event (weak enable)
1290 * LTTNG_KERNEL_DISABLE
1291 * Disable recording for this event (strong disable)
1294 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1296 struct lttng_event
*event
= file
->private_data
;
1299 case LTTNG_KERNEL_OLD_CONTEXT
:
1301 struct lttng_kernel_context
*ucontext_param
;
1302 struct lttng_kernel_old_context
*old_ucontext_param
;
1305 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1307 if (!ucontext_param
) {
1311 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1313 if (!old_ucontext_param
) {
1315 goto old_ctx_error_free_param
;
1318 if (copy_from_user(old_ucontext_param
,
1319 (struct lttng_kernel_old_context __user
*) arg
,
1320 sizeof(struct lttng_kernel_old_context
))) {
1322 goto old_ctx_error_free_old_param
;
1324 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1325 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1326 sizeof(ucontext_param
->padding
));
1327 /* only type that uses the union */
1328 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1329 ucontext_param
->u
.perf_counter
.type
=
1330 old_ucontext_param
->u
.perf_counter
.type
;
1331 ucontext_param
->u
.perf_counter
.config
=
1332 old_ucontext_param
->u
.perf_counter
.config
;
1333 memcpy(ucontext_param
->u
.perf_counter
.name
,
1334 old_ucontext_param
->u
.perf_counter
.name
,
1335 sizeof(ucontext_param
->u
.perf_counter
.name
));
1338 ret
= lttng_abi_add_context(file
,
1340 &event
->ctx
, event
->chan
->session
);
1342 old_ctx_error_free_old_param
:
1343 kfree(old_ucontext_param
);
1344 old_ctx_error_free_param
:
1345 kfree(ucontext_param
);
1349 case LTTNG_KERNEL_CONTEXT
:
1351 struct lttng_kernel_context ucontext_param
;
1353 if (copy_from_user(&ucontext_param
,
1354 (struct lttng_kernel_context __user
*) arg
,
1355 sizeof(ucontext_param
)))
1357 return lttng_abi_add_context(file
,
1359 &event
->ctx
, event
->chan
->session
);
1361 case LTTNG_KERNEL_OLD_ENABLE
:
1362 case LTTNG_KERNEL_ENABLE
:
1363 return lttng_event_enable(event
);
1364 case LTTNG_KERNEL_OLD_DISABLE
:
1365 case LTTNG_KERNEL_DISABLE
:
1366 return lttng_event_disable(event
);
1368 return -ENOIOCTLCMD
;
1373 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1375 struct lttng_event
*event
= file
->private_data
;
1378 fput(event
->chan
->file
);
1382 /* TODO: filter control ioctl */
1383 static const struct file_operations lttng_event_fops
= {
1384 .owner
= THIS_MODULE
,
1385 .release
= lttng_event_release
,
1386 .unlocked_ioctl
= lttng_event_ioctl
,
1387 #ifdef CONFIG_COMPAT
1388 .compat_ioctl
= lttng_event_ioctl
,
1392 static int put_u64(uint64_t val
, unsigned long arg
)
1394 return put_user(val
, (uint64_t __user
*) arg
);
1397 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1398 unsigned int cmd
, unsigned long arg
)
1400 struct lib_ring_buffer
*buf
= filp
->private_data
;
1401 struct channel
*chan
= buf
->backend
.chan
;
1402 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1403 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1406 if (atomic_read(&chan
->record_disabled
))
1410 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1414 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1417 return put_u64(ts
, arg
);
1419 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1423 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1426 return put_u64(ts
, arg
);
1428 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1432 ret
= ops
->events_discarded(config
, buf
, &ed
);
1435 return put_u64(ed
, arg
);
1437 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1441 ret
= ops
->content_size(config
, buf
, &cs
);
1444 return put_u64(cs
, arg
);
1446 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1450 ret
= ops
->packet_size(config
, buf
, &ps
);
1453 return put_u64(ps
, arg
);
1455 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1459 ret
= ops
->stream_id(config
, buf
, &si
);
1462 return put_u64(si
, arg
);
1464 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1468 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1471 return put_u64(ts
, arg
);
1474 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1482 #ifdef CONFIG_COMPAT
1483 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1484 unsigned int cmd
, unsigned long arg
)
1486 struct lib_ring_buffer
*buf
= filp
->private_data
;
1487 struct channel
*chan
= buf
->backend
.chan
;
1488 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1489 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1492 if (atomic_read(&chan
->record_disabled
))
1496 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1500 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1503 return put_u64(ts
, arg
);
1505 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1509 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1512 return put_u64(ts
, arg
);
1514 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1518 ret
= ops
->events_discarded(config
, buf
, &ed
);
1521 return put_u64(ed
, arg
);
1523 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1527 ret
= ops
->content_size(config
, buf
, &cs
);
1530 return put_u64(cs
, arg
);
1532 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1536 ret
= ops
->packet_size(config
, buf
, &ps
);
1539 return put_u64(ps
, arg
);
1541 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1545 ret
= ops
->stream_id(config
, buf
, &si
);
1548 return put_u64(si
, arg
);
1550 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1554 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1557 return put_u64(ts
, arg
);
1560 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1567 #endif /* CONFIG_COMPAT */
1569 static void lttng_stream_override_ring_buffer_fops(void)
1571 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1572 lttng_stream_ring_buffer_file_operations
.open
=
1573 lib_ring_buffer_file_operations
.open
;
1574 lttng_stream_ring_buffer_file_operations
.release
=
1575 lib_ring_buffer_file_operations
.release
;
1576 lttng_stream_ring_buffer_file_operations
.poll
=
1577 lib_ring_buffer_file_operations
.poll
;
1578 lttng_stream_ring_buffer_file_operations
.splice_read
=
1579 lib_ring_buffer_file_operations
.splice_read
;
1580 lttng_stream_ring_buffer_file_operations
.mmap
=
1581 lib_ring_buffer_file_operations
.mmap
;
1582 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1583 lttng_stream_ring_buffer_ioctl
;
1584 lttng_stream_ring_buffer_file_operations
.llseek
=
1585 lib_ring_buffer_file_operations
.llseek
;
1586 #ifdef CONFIG_COMPAT
1587 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1588 lttng_stream_ring_buffer_compat_ioctl
;
1592 int __init
lttng_abi_init(void)
1596 wrapper_vmalloc_sync_all();
1597 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1600 if (!lttng_proc_dentry
) {
1601 printk(KERN_ERR
"Error creating LTTng control file\n");
1605 lttng_stream_override_ring_buffer_fops();
1611 /* No __exit annotation because used by init error path too. */
1612 void lttng_abi_exit(void)
1614 if (lttng_proc_dentry
)
1615 remove_proc_entry("lttng", NULL
);