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 "lttng-abi.h"
53 #include "lttng-abi-old.h"
54 #include "lttng-events.h"
55 #include "lttng-tracer.h"
56 #include "lib/ringbuffer/frontend_types.h"
59 * This is LTTng's own personal way to create a system call as an external
60 * module. We use ioctl() on /proc/lttng.
63 static struct proc_dir_entry
*lttng_proc_dentry
;
64 static const struct file_operations lttng_fops
;
65 static const struct file_operations lttng_session_fops
;
66 static const struct file_operations lttng_channel_fops
;
67 static const struct file_operations lttng_metadata_fops
;
68 static const struct file_operations lttng_event_fops
;
69 static struct file_operations lttng_stream_ring_buffer_file_operations
;
72 * Teardown management: opened file descriptors keep a refcount on the module,
73 * so it can only exit when all file descriptors are closed.
77 int lttng_abi_create_session(void)
79 struct lttng_session
*session
;
80 struct file
*session_file
;
83 session
= lttng_session_create();
86 session_fd
= get_unused_fd();
91 session_file
= anon_inode_getfile("[lttng_session]",
94 if (IS_ERR(session_file
)) {
95 ret
= PTR_ERR(session_file
);
98 session
->file
= session_file
;
99 fd_install(session_fd
, session_file
);
103 put_unused_fd(session_fd
);
105 lttng_session_destroy(session
);
110 int lttng_abi_tracepoint_list(void)
112 struct file
*tracepoint_list_file
;
115 file_fd
= get_unused_fd();
121 tracepoint_list_file
= anon_inode_getfile("[lttng_tracepoint_list]",
122 <tng_tracepoint_list_fops
,
124 if (IS_ERR(tracepoint_list_file
)) {
125 ret
= PTR_ERR(tracepoint_list_file
);
128 ret
= lttng_tracepoint_list_fops
.open(NULL
, tracepoint_list_file
);
131 fd_install(file_fd
, tracepoint_list_file
);
139 fput(tracepoint_list_file
);
141 put_unused_fd(file_fd
);
147 int lttng_abi_syscall_list(void)
149 struct file
*syscall_list_file
;
152 file_fd
= get_unused_fd();
158 syscall_list_file
= anon_inode_getfile("[lttng_syscall_list]",
159 <tng_syscall_list_fops
,
161 if (IS_ERR(syscall_list_file
)) {
162 ret
= PTR_ERR(syscall_list_file
);
165 ret
= lttng_syscall_list_fops
.open(NULL
, syscall_list_file
);
168 fd_install(file_fd
, syscall_list_file
);
176 fput(syscall_list_file
);
178 put_unused_fd(file_fd
);
184 void lttng_abi_tracer_version(struct lttng_kernel_tracer_version
*v
)
186 v
->major
= LTTNG_MODULES_MAJOR_VERSION
;
187 v
->minor
= LTTNG_MODULES_MINOR_VERSION
;
188 v
->patchlevel
= LTTNG_MODULES_PATCHLEVEL_VERSION
;
192 long lttng_abi_add_context(struct file
*file
,
193 struct lttng_kernel_context
*context_param
,
194 struct lttng_ctx
**ctx
, struct lttng_session
*session
)
197 if (session
->been_active
)
200 switch (context_param
->ctx
) {
201 case LTTNG_KERNEL_CONTEXT_PID
:
202 return lttng_add_pid_to_ctx(ctx
);
203 case LTTNG_KERNEL_CONTEXT_PRIO
:
204 return lttng_add_prio_to_ctx(ctx
);
205 case LTTNG_KERNEL_CONTEXT_NICE
:
206 return lttng_add_nice_to_ctx(ctx
);
207 case LTTNG_KERNEL_CONTEXT_VPID
:
208 return lttng_add_vpid_to_ctx(ctx
);
209 case LTTNG_KERNEL_CONTEXT_TID
:
210 return lttng_add_tid_to_ctx(ctx
);
211 case LTTNG_KERNEL_CONTEXT_VTID
:
212 return lttng_add_vtid_to_ctx(ctx
);
213 case LTTNG_KERNEL_CONTEXT_PPID
:
214 return lttng_add_ppid_to_ctx(ctx
);
215 case LTTNG_KERNEL_CONTEXT_VPPID
:
216 return lttng_add_vppid_to_ctx(ctx
);
217 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER
:
218 context_param
->u
.perf_counter
.name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
219 return lttng_add_perf_counter_to_ctx(context_param
->u
.perf_counter
.type
,
220 context_param
->u
.perf_counter
.config
,
221 context_param
->u
.perf_counter
.name
,
223 case LTTNG_KERNEL_CONTEXT_PROCNAME
:
224 return lttng_add_procname_to_ctx(ctx
);
225 case LTTNG_KERNEL_CONTEXT_HOSTNAME
:
226 return lttng_add_hostname_to_ctx(ctx
);
233 * lttng_ioctl - lttng syscall through ioctl
239 * This ioctl implements lttng commands:
240 * LTTNG_KERNEL_SESSION
241 * Returns a LTTng trace session file descriptor
242 * LTTNG_KERNEL_TRACER_VERSION
243 * Returns the LTTng kernel tracer version
244 * LTTNG_KERNEL_TRACEPOINT_LIST
245 * Returns a file descriptor listing available tracepoints
246 * LTTNG_KERNEL_WAIT_QUIESCENT
247 * Returns after all previously running probes have completed
249 * The returned session will be deleted when its file descriptor is closed.
252 long lttng_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
255 case LTTNG_KERNEL_OLD_SESSION
:
256 case LTTNG_KERNEL_SESSION
:
257 return lttng_abi_create_session();
258 case LTTNG_KERNEL_OLD_TRACER_VERSION
:
260 struct lttng_kernel_tracer_version v
;
261 struct lttng_kernel_old_tracer_version oldv
;
262 struct lttng_kernel_old_tracer_version
*uversion
=
263 (struct lttng_kernel_old_tracer_version __user
*) arg
;
265 lttng_abi_tracer_version(&v
);
266 oldv
.major
= v
.major
;
267 oldv
.minor
= v
.minor
;
268 oldv
.patchlevel
= v
.patchlevel
;
270 if (copy_to_user(uversion
, &oldv
, sizeof(oldv
)))
274 case LTTNG_KERNEL_TRACER_VERSION
:
276 struct lttng_kernel_tracer_version version
;
277 struct lttng_kernel_tracer_version
*uversion
=
278 (struct lttng_kernel_tracer_version __user
*) arg
;
280 lttng_abi_tracer_version(&version
);
282 if (copy_to_user(uversion
, &version
, sizeof(version
)))
286 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST
:
287 case LTTNG_KERNEL_TRACEPOINT_LIST
:
288 return lttng_abi_tracepoint_list();
289 case LTTNG_KERNEL_SYSCALL_LIST
:
290 return lttng_abi_syscall_list();
291 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT
:
292 case LTTNG_KERNEL_WAIT_QUIESCENT
:
295 case LTTNG_KERNEL_OLD_CALIBRATE
:
297 struct lttng_kernel_old_calibrate __user
*ucalibrate
=
298 (struct lttng_kernel_old_calibrate __user
*) arg
;
299 struct lttng_kernel_old_calibrate old_calibrate
;
300 struct lttng_kernel_calibrate calibrate
;
303 if (copy_from_user(&old_calibrate
, ucalibrate
, sizeof(old_calibrate
)))
305 calibrate
.type
= old_calibrate
.type
;
306 ret
= lttng_calibrate(&calibrate
);
307 if (copy_to_user(ucalibrate
, &old_calibrate
, sizeof(old_calibrate
)))
311 case LTTNG_KERNEL_CALIBRATE
:
313 struct lttng_kernel_calibrate __user
*ucalibrate
=
314 (struct lttng_kernel_calibrate __user
*) arg
;
315 struct lttng_kernel_calibrate calibrate
;
318 if (copy_from_user(&calibrate
, ucalibrate
, sizeof(calibrate
)))
320 ret
= lttng_calibrate(&calibrate
);
321 if (copy_to_user(ucalibrate
, &calibrate
, sizeof(calibrate
)))
330 static const struct file_operations lttng_fops
= {
331 .owner
= THIS_MODULE
,
332 .unlocked_ioctl
= lttng_ioctl
,
334 .compat_ioctl
= lttng_ioctl
,
339 int lttng_abi_create_channel(struct file
*session_file
,
340 struct lttng_kernel_channel
*chan_param
,
341 enum channel_type channel_type
)
343 struct lttng_session
*session
= session_file
->private_data
;
344 const struct file_operations
*fops
= NULL
;
345 const char *transport_name
;
346 struct lttng_channel
*chan
;
347 struct file
*chan_file
;
351 chan_fd
= get_unused_fd();
356 switch (channel_type
) {
357 case PER_CPU_CHANNEL
:
358 fops
= <tng_channel_fops
;
360 case METADATA_CHANNEL
:
361 fops
= <tng_metadata_fops
;
365 chan_file
= anon_inode_getfile("[lttng_channel]",
368 if (IS_ERR(chan_file
)) {
369 ret
= PTR_ERR(chan_file
);
372 switch (channel_type
) {
373 case PER_CPU_CHANNEL
:
374 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
) {
375 transport_name
= chan_param
->overwrite
?
376 "relay-overwrite" : "relay-discard";
377 } else if (chan_param
->output
== LTTNG_KERNEL_MMAP
) {
378 transport_name
= chan_param
->overwrite
?
379 "relay-overwrite-mmap" : "relay-discard-mmap";
384 case METADATA_CHANNEL
:
385 if (chan_param
->output
== LTTNG_KERNEL_SPLICE
)
386 transport_name
= "relay-metadata";
387 else if (chan_param
->output
== LTTNG_KERNEL_MMAP
)
388 transport_name
= "relay-metadata-mmap";
393 transport_name
= "<unknown>";
397 * We tolerate no failure path after channel creation. It will stay
398 * invariant for the rest of the session.
400 chan
= lttng_channel_create(session
, transport_name
, NULL
,
401 chan_param
->subbuf_size
,
402 chan_param
->num_subbuf
,
403 chan_param
->switch_timer_interval
,
404 chan_param
->read_timer_interval
,
410 chan
->file
= chan_file
;
411 chan_file
->private_data
= chan
;
412 fd_install(chan_fd
, chan_file
);
413 atomic_long_inc(&session_file
->f_count
);
420 put_unused_fd(chan_fd
);
426 * lttng_session_ioctl - lttng session fd ioctl
432 * This ioctl implements lttng commands:
433 * LTTNG_KERNEL_CHANNEL
434 * Returns a LTTng channel file descriptor
435 * LTTNG_KERNEL_ENABLE
436 * Enables tracing for a session (weak enable)
437 * LTTNG_KERNEL_DISABLE
438 * Disables tracing for a session (strong disable)
439 * LTTNG_KERNEL_METADATA
440 * Returns a LTTng metadata file descriptor
442 * The returned channel will be deleted when its file descriptor is closed.
445 long lttng_session_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
447 struct lttng_session
*session
= file
->private_data
;
450 case LTTNG_KERNEL_OLD_CHANNEL
:
452 struct lttng_kernel_channel chan_param
;
453 struct lttng_kernel_old_channel old_chan_param
;
455 if (copy_from_user(&old_chan_param
,
456 (struct lttng_kernel_old_channel __user
*) arg
,
457 sizeof(struct lttng_kernel_old_channel
)))
459 chan_param
.overwrite
= old_chan_param
.overwrite
;
460 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
461 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
462 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
463 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
464 chan_param
.output
= old_chan_param
.output
;
466 return lttng_abi_create_channel(file
, &chan_param
,
469 case LTTNG_KERNEL_CHANNEL
:
471 struct lttng_kernel_channel chan_param
;
473 if (copy_from_user(&chan_param
,
474 (struct lttng_kernel_channel __user
*) arg
,
475 sizeof(struct lttng_kernel_channel
)))
477 return lttng_abi_create_channel(file
, &chan_param
,
480 case LTTNG_KERNEL_OLD_SESSION_START
:
481 case LTTNG_KERNEL_OLD_ENABLE
:
482 case LTTNG_KERNEL_SESSION_START
:
483 case LTTNG_KERNEL_ENABLE
:
484 return lttng_session_enable(session
);
485 case LTTNG_KERNEL_OLD_SESSION_STOP
:
486 case LTTNG_KERNEL_OLD_DISABLE
:
487 case LTTNG_KERNEL_SESSION_STOP
:
488 case LTTNG_KERNEL_DISABLE
:
489 return lttng_session_disable(session
);
490 case LTTNG_KERNEL_OLD_METADATA
:
492 struct lttng_kernel_channel chan_param
;
493 struct lttng_kernel_old_channel old_chan_param
;
495 if (copy_from_user(&old_chan_param
,
496 (struct lttng_kernel_old_channel __user
*) arg
,
497 sizeof(struct lttng_kernel_old_channel
)))
499 chan_param
.overwrite
= old_chan_param
.overwrite
;
500 chan_param
.subbuf_size
= old_chan_param
.subbuf_size
;
501 chan_param
.num_subbuf
= old_chan_param
.num_subbuf
;
502 chan_param
.switch_timer_interval
= old_chan_param
.switch_timer_interval
;
503 chan_param
.read_timer_interval
= old_chan_param
.read_timer_interval
;
504 chan_param
.output
= old_chan_param
.output
;
506 return lttng_abi_create_channel(file
, &chan_param
,
509 case LTTNG_KERNEL_METADATA
:
511 struct lttng_kernel_channel chan_param
;
513 if (copy_from_user(&chan_param
,
514 (struct lttng_kernel_channel __user
*) arg
,
515 sizeof(struct lttng_kernel_channel
)))
517 return lttng_abi_create_channel(file
, &chan_param
,
526 * Called when the last file reference is dropped.
528 * Big fat note: channels and events are invariant for the whole session after
529 * their creation. So this session destruction also destroys all channel and
530 * event structures specific to this session (they are not destroyed when their
531 * individual file is released).
534 int lttng_session_release(struct inode
*inode
, struct file
*file
)
536 struct lttng_session
*session
= file
->private_data
;
539 lttng_session_destroy(session
);
543 static const struct file_operations lttng_session_fops
= {
544 .owner
= THIS_MODULE
,
545 .release
= lttng_session_release
,
546 .unlocked_ioctl
= lttng_session_ioctl
,
548 .compat_ioctl
= lttng_session_ioctl
,
553 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
557 * Handles the poll operations for the metadata channels.
560 unsigned int lttng_metadata_ring_buffer_poll(struct file
*filp
,
563 struct lttng_metadata_stream
*stream
= filp
->private_data
;
564 struct lib_ring_buffer
*buf
= stream
->priv
;
566 unsigned int mask
= 0;
568 if (filp
->f_mode
& FMODE_READ
) {
569 poll_wait_set_exclusive(wait
);
570 poll_wait(filp
, &stream
->read_wait
, wait
);
572 finalized
= stream
->finalized
;
575 * lib_ring_buffer_is_finalized() contains a smp_rmb()
576 * ordering finalized load before offsets loads.
578 WARN_ON(atomic_long_read(&buf
->active_readers
) != 1);
583 if (stream
->metadata_cache
->metadata_written
>
584 stream
->metadata_out
)
592 void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file
*filp
,
593 unsigned int cmd
, unsigned long arg
)
595 struct lttng_metadata_stream
*stream
= filp
->private_data
;
597 stream
->metadata_out
= stream
->metadata_in
;
601 long lttng_metadata_ring_buffer_ioctl(struct file
*filp
,
602 unsigned int cmd
, unsigned long arg
)
605 struct lttng_metadata_stream
*stream
= filp
->private_data
;
606 struct lib_ring_buffer
*buf
= stream
->priv
;
609 case RING_BUFFER_GET_NEXT_SUBBUF
:
611 struct lttng_metadata_stream
*stream
= filp
->private_data
;
612 struct lib_ring_buffer
*buf
= stream
->priv
;
613 struct channel
*chan
= buf
->backend
.chan
;
615 ret
= lttng_metadata_output_channel(stream
, chan
);
617 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
623 case RING_BUFFER_GET_SUBBUF
:
626 * Random access is not allowed for metadata channel.
630 case RING_BUFFER_FLUSH
:
632 struct lttng_metadata_stream
*stream
= filp
->private_data
;
633 struct lib_ring_buffer
*buf
= stream
->priv
;
634 struct channel
*chan
= buf
->backend
.chan
;
637 * Before doing the actual ring buffer flush, write up to one
638 * packet of metadata in the ring buffer.
640 ret
= lttng_metadata_output_channel(stream
, chan
);
648 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
650 /* Performing lib ring buffer ioctl after our own. */
651 ret
= lib_ring_buffer_ioctl(filp
, cmd
, arg
, buf
);
656 case RING_BUFFER_PUT_NEXT_SUBBUF
:
658 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
671 long lttng_metadata_ring_buffer_compat_ioctl(struct file
*filp
,
672 unsigned int cmd
, unsigned long arg
)
675 struct lttng_metadata_stream
*stream
= filp
->private_data
;
676 struct lib_ring_buffer
*buf
= stream
->priv
;
679 case RING_BUFFER_GET_NEXT_SUBBUF
:
681 struct lttng_metadata_stream
*stream
= filp
->private_data
;
682 struct lib_ring_buffer
*buf
= stream
->priv
;
683 struct channel
*chan
= buf
->backend
.chan
;
685 ret
= lttng_metadata_output_channel(stream
, chan
);
687 lib_ring_buffer_switch_slow(buf
, SWITCH_ACTIVE
);
693 case RING_BUFFER_GET_SUBBUF
:
696 * Random access is not allowed for metadata channel.
703 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
705 /* Performing lib ring buffer ioctl after our own. */
706 ret
= lib_ring_buffer_compat_ioctl(filp
, cmd
, arg
, buf
);
711 case RING_BUFFER_PUT_NEXT_SUBBUF
:
713 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp
,
726 * This is not used by anonymous file descriptors. This code is left
727 * there if we ever want to implement an inode with open() operation.
730 int lttng_metadata_ring_buffer_open(struct inode
*inode
, struct file
*file
)
732 struct lttng_metadata_stream
*stream
= inode
->i_private
;
733 struct lib_ring_buffer
*buf
= stream
->priv
;
735 file
->private_data
= buf
;
737 * Since life-time of metadata cache differs from that of
738 * session, we need to keep our own reference on the transport.
740 if (!try_module_get(stream
->transport
->owner
)) {
741 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
744 return lib_ring_buffer_open(inode
, file
, buf
);
748 int lttng_metadata_ring_buffer_release(struct inode
*inode
, struct file
*file
)
750 struct lttng_metadata_stream
*stream
= file
->private_data
;
751 struct lib_ring_buffer
*buf
= stream
->priv
;
753 kref_put(&stream
->metadata_cache
->refcount
, metadata_cache_destroy
);
754 module_put(stream
->transport
->owner
);
755 return lib_ring_buffer_release(inode
, file
, buf
);
759 ssize_t
lttng_metadata_ring_buffer_splice_read(struct file
*in
, loff_t
*ppos
,
760 struct pipe_inode_info
*pipe
, size_t len
,
763 struct lttng_metadata_stream
*stream
= in
->private_data
;
764 struct lib_ring_buffer
*buf
= stream
->priv
;
766 return lib_ring_buffer_splice_read(in
, ppos
, pipe
, len
,
771 int lttng_metadata_ring_buffer_mmap(struct file
*filp
,
772 struct vm_area_struct
*vma
)
774 struct lttng_metadata_stream
*stream
= filp
->private_data
;
775 struct lib_ring_buffer
*buf
= stream
->priv
;
777 return lib_ring_buffer_mmap(filp
, vma
, buf
);
781 const struct file_operations lttng_metadata_ring_buffer_file_operations
= {
782 .owner
= THIS_MODULE
,
783 .open
= lttng_metadata_ring_buffer_open
,
784 .release
= lttng_metadata_ring_buffer_release
,
785 .poll
= lttng_metadata_ring_buffer_poll
,
786 .splice_read
= lttng_metadata_ring_buffer_splice_read
,
787 .mmap
= lttng_metadata_ring_buffer_mmap
,
788 .unlocked_ioctl
= lttng_metadata_ring_buffer_ioctl
,
789 .llseek
= vfs_lib_ring_buffer_no_llseek
,
791 .compat_ioctl
= lttng_metadata_ring_buffer_compat_ioctl
,
796 int lttng_abi_create_stream_fd(struct file
*channel_file
, void *stream_priv
,
797 const struct file_operations
*fops
)
800 struct file
*stream_file
;
802 stream_fd
= get_unused_fd();
807 stream_file
= anon_inode_getfile("[lttng_stream]", fops
,
808 stream_priv
, O_RDWR
);
809 if (IS_ERR(stream_file
)) {
810 ret
= PTR_ERR(stream_file
);
814 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
815 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
816 * file descriptor, so we set FMODE_PREAD here.
818 stream_file
->f_mode
|= FMODE_PREAD
;
819 fd_install(stream_fd
, stream_file
);
821 * The stream holds a reference to the channel within the generic ring
822 * buffer library, so no need to hold a refcount on the channel and
823 * session files here.
828 put_unused_fd(stream_fd
);
834 int lttng_abi_open_stream(struct file
*channel_file
)
836 struct lttng_channel
*channel
= channel_file
->private_data
;
837 struct lib_ring_buffer
*buf
;
841 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
846 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
847 <tng_stream_ring_buffer_file_operations
);
854 channel
->ops
->buffer_read_close(buf
);
859 int lttng_abi_open_metadata_stream(struct file
*channel_file
)
861 struct lttng_channel
*channel
= channel_file
->private_data
;
862 struct lttng_session
*session
= channel
->session
;
863 struct lib_ring_buffer
*buf
;
865 struct lttng_metadata_stream
*metadata_stream
;
868 buf
= channel
->ops
->buffer_read_open(channel
->chan
);
872 metadata_stream
= kzalloc(sizeof(struct lttng_metadata_stream
),
874 if (!metadata_stream
) {
878 metadata_stream
->metadata_cache
= session
->metadata_cache
;
879 init_waitqueue_head(&metadata_stream
->read_wait
);
880 metadata_stream
->priv
= buf
;
881 stream_priv
= metadata_stream
;
882 metadata_stream
->transport
= channel
->transport
;
883 mutex_init(&metadata_stream
->lock
);
886 * Since life-time of metadata cache differs from that of
887 * session, we need to keep our own reference on the transport.
889 if (!try_module_get(metadata_stream
->transport
->owner
)) {
890 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
895 ret
= lttng_abi_create_stream_fd(channel_file
, stream_priv
,
896 <tng_metadata_ring_buffer_file_operations
);
900 kref_get(&session
->metadata_cache
->refcount
);
901 list_add(&metadata_stream
->list
,
902 &session
->metadata_cache
->metadata_stream
);
906 module_put(metadata_stream
->transport
->owner
);
908 kfree(metadata_stream
);
910 channel
->ops
->buffer_read_close(buf
);
915 int lttng_abi_create_event(struct file
*channel_file
,
916 struct lttng_kernel_event
*event_param
)
918 struct lttng_channel
*channel
= channel_file
->private_data
;
919 struct lttng_event
*event
;
921 struct file
*event_file
;
923 event_param
->name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
924 switch (event_param
->instrumentation
) {
925 case LTTNG_KERNEL_KRETPROBE
:
926 event_param
->u
.kretprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
928 case LTTNG_KERNEL_KPROBE
:
929 event_param
->u
.kprobe
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
931 case LTTNG_KERNEL_FUNCTION
:
932 event_param
->u
.ftrace
.symbol_name
[LTTNG_KERNEL_SYM_NAME_LEN
- 1] = '\0';
937 switch (event_param
->instrumentation
) {
939 event_fd
= get_unused_fd();
944 event_file
= anon_inode_getfile("[lttng_event]",
947 if (IS_ERR(event_file
)) {
948 ret
= PTR_ERR(event_file
);
952 * We tolerate no failure path after event creation. It
953 * will stay invariant for the rest of the session.
955 event
= lttng_event_create(channel
, event_param
, NULL
, NULL
);
956 WARN_ON_ONCE(!event
);
958 ret
= PTR_ERR(event
);
961 event_file
->private_data
= event
;
962 fd_install(event_fd
, event_file
);
963 /* The event holds a reference on the channel */
964 atomic_long_inc(&channel_file
->f_count
);
966 case LTTNG_KERNEL_SYSCALL
:
967 ret
= lttng_syscalls_register(channel
, NULL
);
971 if (event_param
->u
.syscall
.disable
) {
972 ret
= lttng_syscall_filter_disable(channel
,
973 event_param
->name
[0] == '\0' ?
974 NULL
: event_param
->name
);
978 ret
= lttng_syscall_filter_enable(channel
,
979 event_param
->name
[0] == '\0' ?
980 NULL
: event_param
->name
);
991 put_unused_fd(event_fd
);
997 * lttng_channel_ioctl - lttng syscall through ioctl
1003 * This ioctl implements lttng commands:
1004 * LTTNG_KERNEL_STREAM
1005 * Returns an event stream file descriptor or failure.
1006 * (typically, one event stream records events from one CPU)
1007 * LTTNG_KERNEL_EVENT
1008 * Returns an event file descriptor or failure.
1009 * LTTNG_KERNEL_CONTEXT
1010 * Prepend a context field to each event in the channel
1011 * LTTNG_KERNEL_ENABLE
1012 * Enable recording for events in this channel (weak enable)
1013 * LTTNG_KERNEL_DISABLE
1014 * Disable recording for events in this channel (strong disable)
1016 * Channel and event file descriptors also hold a reference on the session.
1019 long lttng_channel_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1021 struct lttng_channel
*channel
= file
->private_data
;
1024 case LTTNG_KERNEL_OLD_STREAM
:
1025 case LTTNG_KERNEL_STREAM
:
1026 return lttng_abi_open_stream(file
);
1027 case LTTNG_KERNEL_OLD_EVENT
:
1029 struct lttng_kernel_event
*uevent_param
;
1030 struct lttng_kernel_old_event
*old_uevent_param
;
1033 uevent_param
= kmalloc(sizeof(struct lttng_kernel_event
),
1035 if (!uevent_param
) {
1039 old_uevent_param
= kmalloc(
1040 sizeof(struct lttng_kernel_old_event
),
1042 if (!old_uevent_param
) {
1044 goto old_event_error_free_param
;
1046 if (copy_from_user(old_uevent_param
,
1047 (struct lttng_kernel_old_event __user
*) arg
,
1048 sizeof(struct lttng_kernel_old_event
))) {
1050 goto old_event_error_free_old_param
;
1053 memcpy(uevent_param
->name
, old_uevent_param
->name
,
1054 sizeof(uevent_param
->name
));
1055 uevent_param
->instrumentation
=
1056 old_uevent_param
->instrumentation
;
1058 switch (old_uevent_param
->instrumentation
) {
1059 case LTTNG_KERNEL_KPROBE
:
1060 uevent_param
->u
.kprobe
.addr
=
1061 old_uevent_param
->u
.kprobe
.addr
;
1062 uevent_param
->u
.kprobe
.offset
=
1063 old_uevent_param
->u
.kprobe
.offset
;
1064 memcpy(uevent_param
->u
.kprobe
.symbol_name
,
1065 old_uevent_param
->u
.kprobe
.symbol_name
,
1066 sizeof(uevent_param
->u
.kprobe
.symbol_name
));
1068 case LTTNG_KERNEL_KRETPROBE
:
1069 uevent_param
->u
.kretprobe
.addr
=
1070 old_uevent_param
->u
.kretprobe
.addr
;
1071 uevent_param
->u
.kretprobe
.offset
=
1072 old_uevent_param
->u
.kretprobe
.offset
;
1073 memcpy(uevent_param
->u
.kretprobe
.symbol_name
,
1074 old_uevent_param
->u
.kretprobe
.symbol_name
,
1075 sizeof(uevent_param
->u
.kretprobe
.symbol_name
));
1077 case LTTNG_KERNEL_FUNCTION
:
1078 memcpy(uevent_param
->u
.ftrace
.symbol_name
,
1079 old_uevent_param
->u
.ftrace
.symbol_name
,
1080 sizeof(uevent_param
->u
.ftrace
.symbol_name
));
1085 ret
= lttng_abi_create_event(file
, uevent_param
);
1087 old_event_error_free_old_param
:
1088 kfree(old_uevent_param
);
1089 old_event_error_free_param
:
1090 kfree(uevent_param
);
1094 case LTTNG_KERNEL_EVENT
:
1096 struct lttng_kernel_event uevent_param
;
1098 if (copy_from_user(&uevent_param
,
1099 (struct lttng_kernel_event __user
*) arg
,
1100 sizeof(uevent_param
)))
1102 return lttng_abi_create_event(file
, &uevent_param
);
1104 case LTTNG_KERNEL_OLD_CONTEXT
:
1106 struct lttng_kernel_context
*ucontext_param
;
1107 struct lttng_kernel_old_context
*old_ucontext_param
;
1110 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1112 if (!ucontext_param
) {
1116 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1118 if (!old_ucontext_param
) {
1120 goto old_ctx_error_free_param
;
1123 if (copy_from_user(old_ucontext_param
,
1124 (struct lttng_kernel_old_context __user
*) arg
,
1125 sizeof(struct lttng_kernel_old_context
))) {
1127 goto old_ctx_error_free_old_param
;
1129 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1130 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1131 sizeof(ucontext_param
->padding
));
1132 /* only type that uses the union */
1133 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1134 ucontext_param
->u
.perf_counter
.type
=
1135 old_ucontext_param
->u
.perf_counter
.type
;
1136 ucontext_param
->u
.perf_counter
.config
=
1137 old_ucontext_param
->u
.perf_counter
.config
;
1138 memcpy(ucontext_param
->u
.perf_counter
.name
,
1139 old_ucontext_param
->u
.perf_counter
.name
,
1140 sizeof(ucontext_param
->u
.perf_counter
.name
));
1143 ret
= lttng_abi_add_context(file
,
1145 &channel
->ctx
, channel
->session
);
1147 old_ctx_error_free_old_param
:
1148 kfree(old_ucontext_param
);
1149 old_ctx_error_free_param
:
1150 kfree(ucontext_param
);
1154 case LTTNG_KERNEL_CONTEXT
:
1156 struct lttng_kernel_context ucontext_param
;
1158 if (copy_from_user(&ucontext_param
,
1159 (struct lttng_kernel_context __user
*) arg
,
1160 sizeof(ucontext_param
)))
1162 return lttng_abi_add_context(file
,
1164 &channel
->ctx
, channel
->session
);
1166 case LTTNG_KERNEL_OLD_ENABLE
:
1167 case LTTNG_KERNEL_ENABLE
:
1168 return lttng_channel_enable(channel
);
1169 case LTTNG_KERNEL_OLD_DISABLE
:
1170 case LTTNG_KERNEL_DISABLE
:
1171 return lttng_channel_disable(channel
);
1173 return -ENOIOCTLCMD
;
1179 * lttng_metadata_ioctl - lttng syscall through ioctl
1185 * This ioctl implements lttng commands:
1186 * LTTNG_KERNEL_STREAM
1187 * Returns an event stream file descriptor or failure.
1189 * Channel and event file descriptors also hold a reference on the session.
1192 long lttng_metadata_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1195 case LTTNG_KERNEL_OLD_STREAM
:
1196 case LTTNG_KERNEL_STREAM
:
1197 return lttng_abi_open_metadata_stream(file
);
1199 return -ENOIOCTLCMD
;
1204 * lttng_channel_poll - lttng stream addition/removal monitoring
1209 unsigned int lttng_channel_poll(struct file
*file
, poll_table
*wait
)
1211 struct lttng_channel
*channel
= file
->private_data
;
1212 unsigned int mask
= 0;
1214 if (file
->f_mode
& FMODE_READ
) {
1215 poll_wait_set_exclusive(wait
);
1216 poll_wait(file
, channel
->ops
->get_hp_wait_queue(channel
->chan
),
1219 if (channel
->ops
->is_disabled(channel
->chan
))
1221 if (channel
->ops
->is_finalized(channel
->chan
))
1223 if (channel
->ops
->buffer_has_read_closed_stream(channel
->chan
))
1224 return POLLIN
| POLLRDNORM
;
1232 int lttng_channel_release(struct inode
*inode
, struct file
*file
)
1234 struct lttng_channel
*channel
= file
->private_data
;
1237 fput(channel
->session
->file
);
1242 int lttng_metadata_channel_release(struct inode
*inode
, struct file
*file
)
1244 struct lttng_channel
*channel
= file
->private_data
;
1247 lttng_metadata_channel_destroy(channel
);
1248 fput(channel
->session
->file
);
1254 static const struct file_operations lttng_channel_fops
= {
1255 .owner
= THIS_MODULE
,
1256 .release
= lttng_channel_release
,
1257 .poll
= lttng_channel_poll
,
1258 .unlocked_ioctl
= lttng_channel_ioctl
,
1259 #ifdef CONFIG_COMPAT
1260 .compat_ioctl
= lttng_channel_ioctl
,
1264 static const struct file_operations lttng_metadata_fops
= {
1265 .owner
= THIS_MODULE
,
1266 .release
= lttng_metadata_channel_release
,
1267 .unlocked_ioctl
= lttng_metadata_ioctl
,
1268 #ifdef CONFIG_COMPAT
1269 .compat_ioctl
= lttng_metadata_ioctl
,
1274 * lttng_event_ioctl - lttng syscall through ioctl
1280 * This ioctl implements lttng commands:
1281 * LTTNG_KERNEL_CONTEXT
1282 * Prepend a context field to each record of this event
1283 * LTTNG_KERNEL_ENABLE
1284 * Enable recording for this event (weak enable)
1285 * LTTNG_KERNEL_DISABLE
1286 * Disable recording for this event (strong disable)
1289 long lttng_event_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1291 struct lttng_event
*event
= file
->private_data
;
1294 case LTTNG_KERNEL_OLD_CONTEXT
:
1296 struct lttng_kernel_context
*ucontext_param
;
1297 struct lttng_kernel_old_context
*old_ucontext_param
;
1300 ucontext_param
= kmalloc(sizeof(struct lttng_kernel_context
),
1302 if (!ucontext_param
) {
1306 old_ucontext_param
= kmalloc(sizeof(struct lttng_kernel_old_context
),
1308 if (!old_ucontext_param
) {
1310 goto old_ctx_error_free_param
;
1313 if (copy_from_user(old_ucontext_param
,
1314 (struct lttng_kernel_old_context __user
*) arg
,
1315 sizeof(struct lttng_kernel_old_context
))) {
1317 goto old_ctx_error_free_old_param
;
1319 ucontext_param
->ctx
= old_ucontext_param
->ctx
;
1320 memcpy(ucontext_param
->padding
, old_ucontext_param
->padding
,
1321 sizeof(ucontext_param
->padding
));
1322 /* only type that uses the union */
1323 if (old_ucontext_param
->ctx
== LTTNG_KERNEL_CONTEXT_PERF_COUNTER
) {
1324 ucontext_param
->u
.perf_counter
.type
=
1325 old_ucontext_param
->u
.perf_counter
.type
;
1326 ucontext_param
->u
.perf_counter
.config
=
1327 old_ucontext_param
->u
.perf_counter
.config
;
1328 memcpy(ucontext_param
->u
.perf_counter
.name
,
1329 old_ucontext_param
->u
.perf_counter
.name
,
1330 sizeof(ucontext_param
->u
.perf_counter
.name
));
1333 ret
= lttng_abi_add_context(file
,
1335 &event
->ctx
, event
->chan
->session
);
1337 old_ctx_error_free_old_param
:
1338 kfree(old_ucontext_param
);
1339 old_ctx_error_free_param
:
1340 kfree(ucontext_param
);
1344 case LTTNG_KERNEL_CONTEXT
:
1346 struct lttng_kernel_context ucontext_param
;
1348 if (copy_from_user(&ucontext_param
,
1349 (struct lttng_kernel_context __user
*) arg
,
1350 sizeof(ucontext_param
)))
1352 return lttng_abi_add_context(file
,
1354 &event
->ctx
, event
->chan
->session
);
1356 case LTTNG_KERNEL_OLD_ENABLE
:
1357 case LTTNG_KERNEL_ENABLE
:
1358 return lttng_event_enable(event
);
1359 case LTTNG_KERNEL_OLD_DISABLE
:
1360 case LTTNG_KERNEL_DISABLE
:
1361 return lttng_event_disable(event
);
1363 return -ENOIOCTLCMD
;
1368 int lttng_event_release(struct inode
*inode
, struct file
*file
)
1370 struct lttng_event
*event
= file
->private_data
;
1373 fput(event
->chan
->file
);
1377 /* TODO: filter control ioctl */
1378 static const struct file_operations lttng_event_fops
= {
1379 .owner
= THIS_MODULE
,
1380 .release
= lttng_event_release
,
1381 .unlocked_ioctl
= lttng_event_ioctl
,
1382 #ifdef CONFIG_COMPAT
1383 .compat_ioctl
= lttng_event_ioctl
,
1387 static int put_u64(uint64_t val
, unsigned long arg
)
1389 return put_user(val
, (uint64_t __user
*) arg
);
1392 static long lttng_stream_ring_buffer_ioctl(struct file
*filp
,
1393 unsigned int cmd
, unsigned long arg
)
1395 struct lib_ring_buffer
*buf
= filp
->private_data
;
1396 struct channel
*chan
= buf
->backend
.chan
;
1397 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1398 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1401 if (atomic_read(&chan
->record_disabled
))
1405 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN
:
1409 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1412 return put_u64(ts
, arg
);
1414 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END
:
1418 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1421 return put_u64(ts
, arg
);
1423 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED
:
1427 ret
= ops
->events_discarded(config
, buf
, &ed
);
1430 return put_u64(ed
, arg
);
1432 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE
:
1436 ret
= ops
->content_size(config
, buf
, &cs
);
1439 return put_u64(cs
, arg
);
1441 case LTTNG_RING_BUFFER_GET_PACKET_SIZE
:
1445 ret
= ops
->packet_size(config
, buf
, &ps
);
1448 return put_u64(ps
, arg
);
1450 case LTTNG_RING_BUFFER_GET_STREAM_ID
:
1454 ret
= ops
->stream_id(config
, buf
, &si
);
1457 return put_u64(si
, arg
);
1459 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1463 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1466 return put_u64(ts
, arg
);
1469 return lib_ring_buffer_file_operations
.unlocked_ioctl(filp
,
1477 #ifdef CONFIG_COMPAT
1478 static long lttng_stream_ring_buffer_compat_ioctl(struct file
*filp
,
1479 unsigned int cmd
, unsigned long arg
)
1481 struct lib_ring_buffer
*buf
= filp
->private_data
;
1482 struct channel
*chan
= buf
->backend
.chan
;
1483 const struct lib_ring_buffer_config
*config
= &chan
->backend
.config
;
1484 const struct lttng_channel_ops
*ops
= chan
->backend
.priv_ops
;
1487 if (atomic_read(&chan
->record_disabled
))
1491 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN
:
1495 ret
= ops
->timestamp_begin(config
, buf
, &ts
);
1498 return put_u64(ts
, arg
);
1500 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END
:
1504 ret
= ops
->timestamp_end(config
, buf
, &ts
);
1507 return put_u64(ts
, arg
);
1509 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED
:
1513 ret
= ops
->events_discarded(config
, buf
, &ed
);
1516 return put_u64(ed
, arg
);
1518 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE
:
1522 ret
= ops
->content_size(config
, buf
, &cs
);
1525 return put_u64(cs
, arg
);
1527 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE
:
1531 ret
= ops
->packet_size(config
, buf
, &ps
);
1534 return put_u64(ps
, arg
);
1536 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID
:
1540 ret
= ops
->stream_id(config
, buf
, &si
);
1543 return put_u64(si
, arg
);
1545 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP
:
1549 ret
= ops
->current_timestamp(config
, buf
, &ts
);
1552 return put_u64(ts
, arg
);
1555 return lib_ring_buffer_file_operations
.compat_ioctl(filp
,
1562 #endif /* CONFIG_COMPAT */
1564 static void lttng_stream_override_ring_buffer_fops(void)
1566 lttng_stream_ring_buffer_file_operations
.owner
= THIS_MODULE
;
1567 lttng_stream_ring_buffer_file_operations
.open
=
1568 lib_ring_buffer_file_operations
.open
;
1569 lttng_stream_ring_buffer_file_operations
.release
=
1570 lib_ring_buffer_file_operations
.release
;
1571 lttng_stream_ring_buffer_file_operations
.poll
=
1572 lib_ring_buffer_file_operations
.poll
;
1573 lttng_stream_ring_buffer_file_operations
.splice_read
=
1574 lib_ring_buffer_file_operations
.splice_read
;
1575 lttng_stream_ring_buffer_file_operations
.mmap
=
1576 lib_ring_buffer_file_operations
.mmap
;
1577 lttng_stream_ring_buffer_file_operations
.unlocked_ioctl
=
1578 lttng_stream_ring_buffer_ioctl
;
1579 lttng_stream_ring_buffer_file_operations
.llseek
=
1580 lib_ring_buffer_file_operations
.llseek
;
1581 #ifdef CONFIG_COMPAT
1582 lttng_stream_ring_buffer_file_operations
.compat_ioctl
=
1583 lttng_stream_ring_buffer_compat_ioctl
;
1587 int __init
lttng_abi_init(void)
1591 wrapper_vmalloc_sync_all();
1592 lttng_proc_dentry
= proc_create_data("lttng", S_IRUSR
| S_IWUSR
, NULL
,
1595 if (!lttng_proc_dentry
) {
1596 printk(KERN_ERR
"Error creating LTTng control file\n");
1600 lttng_stream_override_ring_buffer_fops();
1606 /* No __exit annotation because used by init error path too. */
1607 void lttng_abi_exit(void)
1609 if (lttng_proc_dentry
)
1610 remove_proc_entry("lttng", NULL
);