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 if (stream
->metadata_cache
->metadata_written
>
569 stream
->metadata_out
)
577 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
578 unsigned int cmd
, unsigned long arg
)
580 struct lttng_metadata_stream
*stream
= filp
->private_data
;
582 stream
->metadata_out
= stream
->metadata_in
;
586 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
587 unsigned int cmd
, unsigned long arg
)
590 struct lttng_metadata_stream
*stream
= filp
->private_data
;
591 struct lib_ring_buffer
*buf
= stream
->priv
;
594 case RING_BUFFER_GET_NEXT_SUBBUF
:
596 struct lttng_metadata_stream
*stream
= filp
->private_data
;
597 struct lib_ring_buffer
*buf
= stream
->priv
;
598 struct channel
*chan
= buf
->backend
.chan
;
600 ret
= lttng_metadata_output_channel(stream
, chan
);
602 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
608 case RING_BUFFER_GET_SUBBUF
:
611 * Random access is not allowed for metadata channel.
615 case RING_BUFFER_FLUSH
:
617 struct lttng_metadata_stream
*stream
= filp
->private_data
;
618 struct lib_ring_buffer
*buf
= stream
->priv
;
619 struct channel
*chan
= buf
->backend
.chan
;
622 * Before doing the actual ring buffer flush, write up to one
623 * packet of metadata in the ring buffer.
625 ret
= lttng_metadata_output_channel(stream
, chan
);
633 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
635 /* Performing lib ring buffer ioctl after our own. */
636 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
641 case RING_BUFFER_PUT_NEXT_SUBBUF
:
643 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
656 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
657 unsigned int cmd
, unsigned long arg
)
660 struct lttng_metadata_stream
*stream
= filp
->private_data
;
661 struct lib_ring_buffer
*buf
= stream
->priv
;
664 case RING_BUFFER_GET_NEXT_SUBBUF
:
666 struct lttng_metadata_stream
*stream
= filp
->private_data
;
667 struct lib_ring_buffer
*buf
= stream
->priv
;
668 struct channel
*chan
= buf
->backend
.chan
;
670 ret
= lttng_metadata_output_channel(stream
, chan
);
672 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
678 case RING_BUFFER_GET_SUBBUF
:
681 * Random access is not allowed for metadata channel.
688 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
690 /* Performing lib ring buffer ioctl after our own. */
691 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
696 case RING_BUFFER_PUT_NEXT_SUBBUF
:
698 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
711 * This is not used by anonymous file descriptors. This code is left
712 * there if we ever want to implement an inode with open() operation.
715 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
717 struct lttng_metadata_stream
*stream
= inode
->i_private
;
718 struct lib_ring_buffer
*buf
= stream
->priv
;
720 file
->private_data
= buf
;
722 * Since life-time of metadata cache differs from that of
723 * session, we need to keep our own reference on the transport.
725 if (!try_module_get(stream
->transport
->owner
)) {
726 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
729 return lib_ring_buffer_open(inode
, file
, buf
);
733 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
735 struct lttng_metadata_stream
*stream
= file
->private_data
;
736 struct lib_ring_buffer
*buf
= stream
->priv
;
738 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
739 module_put(stream
->transport
->owner
);
740 return lib_ring_buffer_release(inode
, file
, buf
);
744 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
745 struct pipe_inode_info
*pipe
, size_t len
,
748 struct lttng_metadata_stream
*stream
= in
->private_data
;
749 struct lib_ring_buffer
*buf
= stream
->priv
;
751 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
756 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
757 struct vm_area_struct
*vma
)
759 struct lttng_metadata_stream
*stream
= filp
->private_data
;
760 struct lib_ring_buffer
*buf
= stream
->priv
;
762 return lib_ring_buffer_mmap(filp
, vma
, buf
);
766 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
767 .owner
= THIS_MODULE
,
768 .open
= lttng_metadata_ring_buffer_open
,
769 .release
= lttng_metadata_ring_buffer_release
,
770 .poll
= lttng_metadata_ring_buffer_poll
,
771 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
772 .mmap
= lttng_metadata_ring_buffer_mmap
,
773 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
774 .llseek
= vfs_lib_ring_buffer_no_llseek
,
776 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
781 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
782 const struct file_operations
*fops
)
785 struct file
*stream_file
;
787 stream_fd
= lttng_get_unused_fd();
792 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
793 stream_priv
, O_RDWR
);
794 if (IS_ERR(stream_file
)) {
795 ret
= PTR_ERR(stream_file
);
799 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
800 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
801 * file descriptor, so we set FMODE_PREAD here.
803 stream_file
->f_mode
|= FMODE_PREAD
;
804 fd_install(stream_fd
, stream_file
);
806 * The stream holds a reference to the channel within the generic ring
807 * buffer library, so no need to hold a refcount on the channel and
808 * session files here.
813 put_unused_fd(stream_fd
);
819 int lttng_abi_open_stream(struct file
*channel_file
)
821 struct lttng_channel
*channel
= channel_file
->private_data
;
822 struct lib_ring_buffer
*buf
;
826 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
831 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
832 <tng_stream_ring_buffer_file_operations
);
839 channel
->ops
->buffer_read_close(buf
);
844 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
846 struct lttng_channel
*channel
= channel_file
->private_data
;
847 struct lttng_session
*session
= channel
->session
;
848 struct lib_ring_buffer
*buf
;
850 struct lttng_metadata_stream
*metadata_stream
;
853 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
857 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
859 if (!metadata_stream
) {
863 metadata_stream
->metadata_cache
= session
->metadata_cache
;
864 init_waitqueue_head(&metadata_stream
->read_wait
);
865 metadata_stream
->priv
= buf
;
866 stream_priv
= metadata_stream
;
867 metadata_stream
->transport
= channel
->transport
;
868 mutex_init(&metadata_stream
->lock
);
871 * Since life-time of metadata cache differs from that of
872 * session, we need to keep our own reference on the transport.
874 if (!try_module_get(metadata_stream
->transport
->owner
)) {
875 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
880 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
881 <tng_metadata_ring_buffer_file_operations
);
885 kref_get(&session
->metadata_cache
->refcount
);
886 list_add(&metadata_stream
->list
,
887 &session
->metadata_cache
->metadata_stream
);
891 module_put(metadata_stream
->transport
->owner
);
893 kfree(metadata_stream
);
895 channel
->ops
->buffer_read_close(buf
);
900 int lttng_abi_create_event(struct file
*channel_file
,
901 struct lttng_kernel_event
*event_param
)
903 struct lttng_channel
*channel
= channel_file
->private_data
;
904 struct lttng_event
*event
;
906 struct file
*event_file
;
908 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
909 switch (event_param
->instrumentation
) {
910 case LTTNG_KERNEL_KRETPROBE
:
911 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
913 case LTTNG_KERNEL_KPROBE
:
914 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
916 case LTTNG_KERNEL_FUNCTION
:
917 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
922 switch (event_param
->instrumentation
) {
924 event_fd
= lttng_get_unused_fd();
929 event_file
= anon_inode_getfile("[lttng_event]",
932 if (IS_ERR(event_file
)) {
933 ret
= PTR_ERR(event_file
);
937 * We tolerate no failure path after event creation. It
938 * will stay invariant for the rest of the session.
940 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
941 WARN_ON_ONCE(!event
);
943 ret
= PTR_ERR(event
);
946 event_file
->private_data
= event
;
947 fd_install(event_fd
, event_file
);
948 /* The event holds a reference on the channel */
949 atomic_long_inc(&channel_file
->f_count
);
951 case LTTNG_KERNEL_SYSCALL
:
952 ret
= lttng_syscalls_register(channel
, NULL
);
956 if (event_param
->u
.syscall
.enable
) {
957 ret
= lttng_syscall_filter_enable(channel
,
958 event_param
->name
[0] == '\0' ?
959 NULL
: event_param
->name
);
964 ret
= lttng_syscall_filter_disable(channel
,
965 event_param
->name
[0] == '\0' ?
966 NULL
: event_param
->name
);
977 put_unused_fd(event_fd
);
983 * lttng_channel_ioctl - lttng syscall through ioctl
989 * This ioctl implements lttng commands:
990 * LTTNG_KERNEL_STREAM
991 * Returns an event stream file descriptor or failure.
992 * (typically, one event stream records events from one CPU)
994 * Returns an event file descriptor or failure.
995 * LTTNG_KERNEL_CONTEXT
996 * Prepend a context field to each event in the channel
997 * LTTNG_KERNEL_ENABLE
998 * Enable recording for events in this channel (weak enable)
999 * LTTNG_KERNEL_DISABLE
1000 * Disable recording for events in this channel (strong disable)
1002 * Channel and event file descriptors also hold a reference on the session.
1005 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1007 struct lttng_channel
*channel
= file
->private_data
;
1010 case LTTNG_KERNEL_OLD_STREAM
:
1011 case LTTNG_KERNEL_STREAM
:
1012 return lttng_abi_open_stream(file
);
1013 case LTTNG_KERNEL_OLD_EVENT
:
1015 struct lttng_kernel_event
*uevent_param
;
1016 struct lttng_kernel_old_event
*old_uevent_param
;
1019 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1021 if (!uevent_param
) {
1025 old_uevent_param
= kmalloc(
1026 sizeof(struct lttng_kernel_old_event
),
1028 if (!old_uevent_param
) {
1030 goto old_event_error_free_param
;
1032 if (copy_from_user(old_uevent_param
,
1033 (struct lttng_kernel_old_event __user
*) arg
,
1034 sizeof(struct lttng_kernel_old_event
))) {
1036 goto old_event_error_free_old_param
;
1039 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1040 sizeof(uevent_param
->name
));
1041 uevent_param
->instrumentation
=
1042 old_uevent_param
->instrumentation
;
1044 switch (old_uevent_param
->instrumentation
) {
1045 case LTTNG_KERNEL_KPROBE
:
1046 uevent_param
->u
.kprobe
.addr
=
1047 old_uevent_param
->u
.kprobe
.addr
;
1048 uevent_param
->u
.kprobe
.offset
=
1049 old_uevent_param
->u
.kprobe
.offset
;
1050 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1051 old_uevent_param
->u
.kprobe
.symbol_name
,
1052 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1054 case LTTNG_KERNEL_KRETPROBE
:
1055 uevent_param
->u
.kretprobe
.addr
=
1056 old_uevent_param
->u
.kretprobe
.addr
;
1057 uevent_param
->u
.kretprobe
.offset
=
1058 old_uevent_param
->u
.kretprobe
.offset
;
1059 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1060 old_uevent_param
->u
.kretprobe
.symbol_name
,
1061 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1063 case LTTNG_KERNEL_FUNCTION
:
1064 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1065 old_uevent_param
->u
.ftrace
.symbol_name
,
1066 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1071 ret
= lttng_abi_create_event(file
, uevent_param
);
1073 old_event_error_free_old_param
:
1074 kfree(old_uevent_param
);
1075 old_event_error_free_param
:
1076 kfree(uevent_param
);
1080 case LTTNG_KERNEL_EVENT
:
1082 struct lttng_kernel_event uevent_param
;
1084 if (copy_from_user(&uevent_param
,
1085 (struct lttng_kernel_event __user
*) arg
,
1086 sizeof(uevent_param
)))
1088 return lttng_abi_create_event(file
, &uevent_param
);
1090 case LTTNG_KERNEL_OLD_CONTEXT
:
1092 struct lttng_kernel_context
*ucontext_param
;
1093 struct lttng_kernel_old_context
*old_ucontext_param
;
1096 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1098 if (!ucontext_param
) {
1102 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1104 if (!old_ucontext_param
) {
1106 goto old_ctx_error_free_param
;
1109 if (copy_from_user(old_ucontext_param
,
1110 (struct lttng_kernel_old_context __user
*) arg
,
1111 sizeof(struct lttng_kernel_old_context
))) {
1113 goto old_ctx_error_free_old_param
;
1115 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1116 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1117 sizeof(ucontext_param
->padding
));
1118 /* only type that uses the union */
1119 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1120 ucontext_param
->u
.perf_counter
.type
=
1121 old_ucontext_param
->u
.perf_counter
.type
;
1122 ucontext_param
->u
.perf_counter
.config
=
1123 old_ucontext_param
->u
.perf_counter
.config
;
1124 memcpy(ucontext_param
->u
.perf_counter
.name
,
1125 old_ucontext_param
->u
.perf_counter
.name
,
1126 sizeof(ucontext_param
->u
.perf_counter
.name
));
1129 ret
= lttng_abi_add_context(file
,
1131 &channel
->ctx
, channel
->session
);
1133 old_ctx_error_free_old_param
:
1134 kfree(old_ucontext_param
);
1135 old_ctx_error_free_param
:
1136 kfree(ucontext_param
);
1140 case LTTNG_KERNEL_CONTEXT
:
1142 struct lttng_kernel_context ucontext_param
;
1144 if (copy_from_user(&ucontext_param
,
1145 (struct lttng_kernel_context __user
*) arg
,
1146 sizeof(ucontext_param
)))
1148 return lttng_abi_add_context(file
,
1150 &channel
->ctx
, channel
->session
);
1152 case LTTNG_KERNEL_OLD_ENABLE
:
1153 case LTTNG_KERNEL_ENABLE
:
1154 return lttng_channel_enable(channel
);
1155 case LTTNG_KERNEL_OLD_DISABLE
:
1156 case LTTNG_KERNEL_DISABLE
:
1157 return lttng_channel_disable(channel
);
1158 case LTTNG_KERNEL_SYSCALL_MASK
:
1159 return lttng_channel_syscall_mask(channel
,
1160 (struct lttng_kernel_syscall_mask __user
*) arg
);
1162 return -ENOIOCTLCMD
;
1168 * lttng_metadata_ioctl - lttng syscall through ioctl
1174 * This ioctl implements lttng commands:
1175 * LTTNG_KERNEL_STREAM
1176 * Returns an event stream file descriptor or failure.
1178 * Channel and event file descriptors also hold a reference on the session.
1181 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1184 case LTTNG_KERNEL_OLD_STREAM
:
1185 case LTTNG_KERNEL_STREAM
:
1186 return lttng_abi_open_metadata_stream(file
);
1188 return -ENOIOCTLCMD
;
1193 * lttng_channel_poll - lttng stream addition/removal monitoring
1198 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1200 struct lttng_channel
*channel
= file
->private_data
;
1201 unsigned int mask
= 0;
1203 if (file
->f_mode
& FMODE_READ
) {
1204 poll_wait_set_exclusive(wait
);
1205 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1208 if (channel
->ops
->is_disabled(channel
->chan
))
1210 if (channel
->ops
->is_finalized(channel
->chan
))
1212 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1213 return POLLIN
| POLLRDNORM
;
1221 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1223 struct lttng_channel
*channel
= file
->private_data
;
1226 fput(channel
->session
->file
);
1231 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1233 struct lttng_channel
*channel
= file
->private_data
;
1236 lttng_metadata_channel_destroy(channel
);
1237 fput(channel
->session
->file
);
1243 static const struct file_operations lttng_channel_fops
= {
1244 .owner
= THIS_MODULE
,
1245 .release
= lttng_channel_release
,
1246 .poll
= lttng_channel_poll
,
1247 .unlocked_ioctl
= lttng_channel_ioctl
,
1248 #ifdef CONFIG_COMPAT
1249 .compat_ioctl
= lttng_channel_ioctl
,
1253 static const struct file_operations lttng_metadata_fops
= {
1254 .owner
= THIS_MODULE
,
1255 .release
= lttng_metadata_channel_release
,
1256 .unlocked_ioctl
= lttng_metadata_ioctl
,
1257 #ifdef CONFIG_COMPAT
1258 .compat_ioctl
= lttng_metadata_ioctl
,
1263 * lttng_event_ioctl - lttng syscall through ioctl
1269 * This ioctl implements lttng commands:
1270 * LTTNG_KERNEL_CONTEXT
1271 * Prepend a context field to each record of this event
1272 * LTTNG_KERNEL_ENABLE
1273 * Enable recording for this event (weak enable)
1274 * LTTNG_KERNEL_DISABLE
1275 * Disable recording for this event (strong disable)
1278 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1280 struct lttng_event
*event
= file
->private_data
;
1283 case LTTNG_KERNEL_OLD_CONTEXT
:
1285 struct lttng_kernel_context
*ucontext_param
;
1286 struct lttng_kernel_old_context
*old_ucontext_param
;
1289 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1291 if (!ucontext_param
) {
1295 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1297 if (!old_ucontext_param
) {
1299 goto old_ctx_error_free_param
;
1302 if (copy_from_user(old_ucontext_param
,
1303 (struct lttng_kernel_old_context __user
*) arg
,
1304 sizeof(struct lttng_kernel_old_context
))) {
1306 goto old_ctx_error_free_old_param
;
1308 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1309 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1310 sizeof(ucontext_param
->padding
));
1311 /* only type that uses the union */
1312 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1313 ucontext_param
->u
.perf_counter
.type
=
1314 old_ucontext_param
->u
.perf_counter
.type
;
1315 ucontext_param
->u
.perf_counter
.config
=
1316 old_ucontext_param
->u
.perf_counter
.config
;
1317 memcpy(ucontext_param
->u
.perf_counter
.name
,
1318 old_ucontext_param
->u
.perf_counter
.name
,
1319 sizeof(ucontext_param
->u
.perf_counter
.name
));
1322 ret
= lttng_abi_add_context(file
,
1324 &event
->ctx
, event
->chan
->session
);
1326 old_ctx_error_free_old_param
:
1327 kfree(old_ucontext_param
);
1328 old_ctx_error_free_param
:
1329 kfree(ucontext_param
);
1333 case LTTNG_KERNEL_CONTEXT
:
1335 struct lttng_kernel_context ucontext_param
;
1337 if (copy_from_user(&ucontext_param
,
1338 (struct lttng_kernel_context __user
*) arg
,
1339 sizeof(ucontext_param
)))
1341 return lttng_abi_add_context(file
,
1343 &event
->ctx
, event
->chan
->session
);
1345 case LTTNG_KERNEL_OLD_ENABLE
:
1346 case LTTNG_KERNEL_ENABLE
:
1347 return lttng_event_enable(event
);
1348 case LTTNG_KERNEL_OLD_DISABLE
:
1349 case LTTNG_KERNEL_DISABLE
:
1350 return lttng_event_disable(event
);
1352 return -ENOIOCTLCMD
;
1357 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1359 struct lttng_event
*event
= file
->private_data
;
1362 fput(event
->chan
->file
);
1366 /* TODO: filter control ioctl */
1367 static const struct file_operations lttng_event_fops
= {
1368 .owner
= THIS_MODULE
,
1369 .release
= lttng_event_release
,
1370 .unlocked_ioctl
= lttng_event_ioctl
,
1371 #ifdef CONFIG_COMPAT
1372 .compat_ioctl
= lttng_event_ioctl
,
1376 static int put_u64(uint64_t val
, unsigned long arg
)
1378 return put_user(val
, (uint64_t __user
*) arg
);
1381 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1382 unsigned int cmd
, unsigned long arg
)
1384 struct lib_ring_buffer
*buf
= filp
->private_data
;
1385 struct channel
*chan
= buf
->backend
.chan
;
1386 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1387 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1390 if (atomic_read(&chan
->record_disabled
))
1394 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1398 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1401 return put_u64(ts
, arg
);
1403 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1407 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1410 return put_u64(ts
, arg
);
1412 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1416 ret
= ops
->events_discarded(config
, buf
, &ed
);
1419 return put_u64(ed
, arg
);
1421 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1425 ret
= ops
->content_size(config
, buf
, &cs
);
1428 return put_u64(cs
, arg
);
1430 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1434 ret
= ops
->packet_size(config
, buf
, &ps
);
1437 return put_u64(ps
, arg
);
1439 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1443 ret
= ops
->stream_id(config
, buf
, &si
);
1446 return put_u64(si
, arg
);
1448 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1452 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1455 return put_u64(ts
, arg
);
1458 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1466 #ifdef CONFIG_COMPAT
1467 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1468 unsigned int cmd
, unsigned long arg
)
1470 struct lib_ring_buffer
*buf
= filp
->private_data
;
1471 struct channel
*chan
= buf
->backend
.chan
;
1472 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1473 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1476 if (atomic_read(&chan
->record_disabled
))
1480 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1484 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1487 return put_u64(ts
, arg
);
1489 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1493 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1496 return put_u64(ts
, arg
);
1498 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1502 ret
= ops
->events_discarded(config
, buf
, &ed
);
1505 return put_u64(ed
, arg
);
1507 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1511 ret
= ops
->content_size(config
, buf
, &cs
);
1514 return put_u64(cs
, arg
);
1516 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1520 ret
= ops
->packet_size(config
, buf
, &ps
);
1523 return put_u64(ps
, arg
);
1525 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1529 ret
= ops
->stream_id(config
, buf
, &si
);
1532 return put_u64(si
, arg
);
1534 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1538 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1541 return put_u64(ts
, arg
);
1544 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1551 #endif /* CONFIG_COMPAT */
1553 static void lttng_stream_override_ring_buffer_fops(void)
1555 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1556 lttng_stream_ring_buffer_file_operations
.open
=
1557 lib_ring_buffer_file_operations
.open
;
1558 lttng_stream_ring_buffer_file_operations
.release
=
1559 lib_ring_buffer_file_operations
.release
;
1560 lttng_stream_ring_buffer_file_operations
.poll
=
1561 lib_ring_buffer_file_operations
.poll
;
1562 lttng_stream_ring_buffer_file_operations
.splice_read
=
1563 lib_ring_buffer_file_operations
.splice_read
;
1564 lttng_stream_ring_buffer_file_operations
.mmap
=
1565 lib_ring_buffer_file_operations
.mmap
;
1566 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1567 lttng_stream_ring_buffer_ioctl
;
1568 lttng_stream_ring_buffer_file_operations
.llseek
=
1569 lib_ring_buffer_file_operations
.llseek
;
1570 #ifdef CONFIG_COMPAT
1571 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1572 lttng_stream_ring_buffer_compat_ioctl
;
1576 int __init
lttng_abi_init(void)
1580 wrapper_vmalloc_sync_all();
1581 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1584 if (!lttng_proc_dentry
) {
1585 printk(KERN_ERR
"Error creating LTTng control file\n");
1589 lttng_stream_override_ring_buffer_fops();
1595 /* No __exit annotation because used by init error path too. */
1596 void lttng_abi_exit(void)
1598 if (lttng_proc_dentry
)
1599 remove_proc_entry("lttng", NULL
);