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Introduce lttng smp_store_release smp_load_acquire wrappers
[lttng-modules.git] / src / lttng-abi.c
CommitLineData
b7cdc182 1/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed 2 *
e8951e63 3 * lttng-abi.c
baf20995 4 *
e8951e63 5 * LTTng ABI
baf20995 6 *
886d51a3
MD		 7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 *
baf20995
MD		 9 * Mimic system calls for:
10 * - session creation, returns a file descriptor or failure.
ad1c05e1
MD		 11 * - channel creation, returns a file descriptor or failure.
12 * - Operates on a session file descriptor
13 * - Takes all channel options as parameters.
14 * - stream get, returns a file descriptor or failure.
15 * - Operates on a channel file descriptor.
16 * - stream notifier get, returns a file descriptor or failure.
17 * - Operates on a channel file descriptor.
18 * - event creation, returns a file descriptor or failure.
19 * - Operates on a channel file descriptor
20 * - Takes an event name as parameter
21 * - Takes an instrumentation source as parameter
22 * - e.g. tracepoints, dynamic_probes...
23 * - Takes instrumentation source specific arguments.
baf20995
MD		 24 */
25
11b5a3c2 26#include <linux/module.h>
e6a17f26 27#include <linux/proc_fs.h>
11b5a3c2
MD		 28#include <linux/anon_inodes.h>
29#include <linux/file.h>
30#include <linux/uaccess.h>
31#include <linux/slab.h>
abc0446a 32#include <linux/err.h>
263b6c88 33#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
24591303
MD		 34#include <ringbuffer/vfs.h>
35#include <ringbuffer/backend.h>
36#include <ringbuffer/frontend.h>
241ae9a8
MD		 37#include <wrapper/poll.h>
38#include <wrapper/file.h>
39#include <wrapper/kref.h>
6657edec 40#include <wrapper/barrier.h>
2df37e95
MD		 41#include <lttng/string-utils.h>
42#include <lttng/abi.h>
43#include <lttng/abi-old.h>
44#include <lttng/events.h>
45#include <lttng/tracer.h>
46#include <lttng/tp-mempool.h>
24591303 47#include <ringbuffer/frontend_types.h>
db2511b4 48#include <ringbuffer/iterator.h>
baf20995
MD		 49
50/*
51 * This is LTTng's own personal way to create a system call as an external
80996790 52 * module. We use ioctl() on /proc/lttng.
baf20995
MD		 53 */
54
e6a17f26 55static struct proc_dir_entry *lttng_proc_dentry;
059de147
MJ		 56
57#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
58static const struct proc_ops lttng_proc_ops;
59#else
60static const struct file_operations lttng_proc_ops;
61#endif
62
ad1c05e1 63static const struct file_operations lttng_session_fops;
750b05f2 64static const struct file_operations lttng_event_notifier_group_fops;
ad1c05e1 65static const struct file_operations lttng_channel_fops;
5dbbdb43 66static const struct file_operations lttng_metadata_fops;
305d3e42 67static const struct file_operations lttng_event_fops;
ed8d02d6 68static struct file_operations lttng_stream_ring_buffer_file_operations;
baf20995 69
9616f0bf 70static int put_u64(uint64_t val, unsigned long arg);
8b97fd42 71static int put_u32(uint32_t val, unsigned long arg);
9616f0bf 72
99f52fcc
FD		 73static int validate_zeroed_padding(char *p, size_t len)
74{
75 size_t i;
76
77 for (i = 0; i < len; i++) {
78 if (p[i])
79 return -1;
80 }
81 return 0;
82}
83
a33c9927
MD		 84/*
85 * Teardown management: opened file descriptors keep a refcount on the module,
86 * so it can only exit when all file descriptors are closed.
87 */
88
ad1c05e1 89static
baf20995
MD		 90int lttng_abi_create_session(void)
91{
a90917c3 92 struct lttng_session *session;
c0e31d2e 93 struct file *session_file;
11b5a3c2 94 int session_fd, ret;
baf20995 95
a90917c3 96 session = lttng_session_create();
baf20995
MD		 97 if (!session)
98 return -ENOMEM;
4ac10b76 99 session_fd = lttng_get_unused_fd();
baf20995
MD		 100 if (session_fd < 0) {
101 ret = session_fd;
102 goto fd_error;
103 }
c0e31d2e 104 session_file = anon_inode_getfile("[lttng_session]",
ad1c05e1 105 &lttng_session_fops,
baf20995 106 session, O_RDWR);
c0e31d2e
MD		 107 if (IS_ERR(session_file)) {
108 ret = PTR_ERR(session_file);
baf20995
MD		 109 goto file_error;
110 }
c0e31d2e
MD		 111 session->file = session_file;
112 fd_install(session_fd, session_file);
baf20995
MD		 113 return session_fd;
114
115file_error:
116 put_unused_fd(session_fd);
117fd_error:
a90917c3 118 lttng_session_destroy(session);
baf20995
MD		 119 return ret;
120}
121
21f58fb7
FD		 122void event_notifier_send_notification_work_wakeup(struct irq_work *entry)
123{
124 struct lttng_event_notifier_group *event_notifier_group =
125 container_of(entry, struct lttng_event_notifier_group,
126 wakeup_pending);
127 wake_up_interruptible(&event_notifier_group->read_wait);
128}
129
750b05f2
FD		 130static
131int lttng_abi_create_event_notifier_group(void)
132{
133 struct lttng_event_notifier_group *event_notifier_group;
134 struct file *event_notifier_group_file;
135 int event_notifier_group_fd, ret;
136
137 event_notifier_group = lttng_event_notifier_group_create();
138 if (!event_notifier_group)
139 return -ENOMEM;
140
141 event_notifier_group_fd = lttng_get_unused_fd();
142 if (event_notifier_group_fd < 0) {
143 ret = event_notifier_group_fd;
144 goto fd_error;
145 }
146 event_notifier_group_file = anon_inode_getfile("[lttng_event_notifier_group]",
147 &lttng_event_notifier_group_fops,
148 event_notifier_group, O_RDWR);
149 if (IS_ERR(event_notifier_group_file)) {
150 ret = PTR_ERR(event_notifier_group_file);
151 goto file_error;
152 }
153
154 event_notifier_group->file = event_notifier_group_file;
21f58fb7
FD		 155 init_waitqueue_head(&event_notifier_group->read_wait);
156 init_irq_work(&event_notifier_group->wakeup_pending,
157 event_notifier_send_notification_work_wakeup);
750b05f2
FD		 158 fd_install(event_notifier_group_fd, event_notifier_group_file);
159 return event_notifier_group_fd;
160
161file_error:
162 put_unused_fd(event_notifier_group_fd);
163fd_error:
164 lttng_event_notifier_group_destroy(event_notifier_group);
165 return ret;
166}
167
271b6681
MD		 168static
169int lttng_abi_tracepoint_list(void)
170{
171 struct file *tracepoint_list_file;
172 int file_fd, ret;
173
4ac10b76 174 file_fd = lttng_get_unused_fd();
271b6681
MD		 175 if (file_fd < 0) {
176 ret = file_fd;
177 goto fd_error;
178 }
30f18bf0 179
8ee099b6 180 tracepoint_list_file = anon_inode_getfile("[lttng_tracepoint_list]",
271b6681
MD		 181 &lttng_tracepoint_list_fops,
182 NULL, O_RDWR);
183 if (IS_ERR(tracepoint_list_file)) {
184 ret = PTR_ERR(tracepoint_list_file);
185 goto file_error;
186 }
30f18bf0
MD		 187 ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
188 if (ret < 0)
189 goto open_error;
271b6681
MD		 190 fd_install(file_fd, tracepoint_list_file);
191 return file_fd;
192
30f18bf0
MD		 193open_error:
194 fput(tracepoint_list_file);
271b6681
MD		 195file_error:
196 put_unused_fd(file_fd);
197fd_error:
198 return ret;
199}
200
f127e61e
MD		 201#ifndef CONFIG_HAVE_SYSCALL_TRACEPOINTS
202static inline
203int lttng_abi_syscall_list(void)
204{
205 return -ENOSYS;
206}
207#else
208static
209int lttng_abi_syscall_list(void)
210{
211 struct file *syscall_list_file;
212 int file_fd, ret;
213
214 file_fd = lttng_get_unused_fd();
215 if (file_fd < 0) {
216 ret = file_fd;
217 goto fd_error;
218 }
219
220 syscall_list_file = anon_inode_getfile("[lttng_syscall_list]",
221 &lttng_syscall_list_fops,
222 NULL, O_RDWR);
223 if (IS_ERR(syscall_list_file)) {
224 ret = PTR_ERR(syscall_list_file);
225 goto file_error;
226 }
227 ret = lttng_syscall_list_fops.open(NULL, syscall_list_file);
228 if (ret < 0)
229 goto open_error;
230 fd_install(file_fd, syscall_list_file);
f127e61e
MD		 231 return file_fd;
232
233open_error:
234 fput(syscall_list_file);
235file_error:
236 put_unused_fd(file_fd);
237fd_error:
238 return ret;
239}
240#endif
241
80c16bcf 242static
6dccd6c1 243void lttng_abi_tracer_version(struct lttng_kernel_tracer_version *v)
80c16bcf 244{
6dccd6c1
JD		 245 v->major = LTTNG_MODULES_MAJOR_VERSION;
246 v->minor = LTTNG_MODULES_MINOR_VERSION;
247 v->patchlevel = LTTNG_MODULES_PATCHLEVEL_VERSION;
80c16bcf
MD		 248}
249
42cabb80
MD		 250static
251void lttng_abi_tracer_abi_version(struct lttng_kernel_tracer_abi_version *v)
252{
253 v->major = LTTNG_MODULES_ABI_MAJOR_VERSION;
254 v->minor = LTTNG_MODULES_ABI_MINOR_VERSION;
255}
256
8070f5c0
MD		 257static
258long lttng_abi_add_context(struct file *file,
6dccd6c1 259 struct lttng_kernel_context *context_param,
a90917c3 260 struct lttng_ctx **ctx, struct lttng_session *session)
8070f5c0 261{
8070f5c0
MD		 262
263 if (session->been_active)
264 return -EPERM;
265
6dccd6c1 266 switch (context_param->ctx) {
12a313a5 267 case LTTNG_KERNEL_CONTEXT_PID:
8070f5c0 268 return lttng_add_pid_to_ctx(ctx);
a8ad3613
MD		 269 case LTTNG_KERNEL_CONTEXT_PRIO:
270 return lttng_add_prio_to_ctx(ctx);
53f1f0ca
MD		 271 case LTTNG_KERNEL_CONTEXT_NICE:
272 return lttng_add_nice_to_ctx(ctx);
b64bc438
MD		 273 case LTTNG_KERNEL_CONTEXT_VPID:
274 return lttng_add_vpid_to_ctx(ctx);
275 case LTTNG_KERNEL_CONTEXT_TID:
276 return lttng_add_tid_to_ctx(ctx);
277 case LTTNG_KERNEL_CONTEXT_VTID:
278 return lttng_add_vtid_to_ctx(ctx);
279 case LTTNG_KERNEL_CONTEXT_PPID:
280 return lttng_add_ppid_to_ctx(ctx);
281 case LTTNG_KERNEL_CONTEXT_VPPID:
282 return lttng_add_vppid_to_ctx(ctx);
12a313a5 283 case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
6dccd6c1
JD		 284 context_param->u.perf_counter.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
285 return lttng_add_perf_counter_to_ctx(context_param->u.perf_counter.type,
286 context_param->u.perf_counter.config,
287 context_param->u.perf_counter.name,
c24a0d71 288 ctx);
a2563e83
MD		 289 case LTTNG_KERNEL_CONTEXT_PROCNAME:
290 return lttng_add_procname_to_ctx(ctx);
975da2c0
JD		 291 case LTTNG_KERNEL_CONTEXT_HOSTNAME:
292 return lttng_add_hostname_to_ctx(ctx);
b3699d90
MD		 293 case LTTNG_KERNEL_CONTEXT_CPU_ID:
294 return lttng_add_cpu_id_to_ctx(ctx);
79150a49
JD		 295 case LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE:
296 return lttng_add_interruptible_to_ctx(ctx);
297 case LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE:
298 return lttng_add_need_reschedule_to_ctx(ctx);
299 case LTTNG_KERNEL_CONTEXT_PREEMPTIBLE:
300 return lttng_add_preemptible_to_ctx(ctx);
301 case LTTNG_KERNEL_CONTEXT_MIGRATABLE:
302 return lttng_add_migratable_to_ctx(ctx);
2fa2d39a
FG		 303 case LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL:
304 case LTTNG_KERNEL_CONTEXT_CALLSTACK_USER:
305 return lttng_add_callstack_to_ctx(ctx, context_param->ctx);
a6cf40a4
MJ		 306 case LTTNG_KERNEL_CONTEXT_CGROUP_NS:
307 return lttng_add_cgroup_ns_to_ctx(ctx);
308 case LTTNG_KERNEL_CONTEXT_IPC_NS:
309 return lttng_add_ipc_ns_to_ctx(ctx);
310 case LTTNG_KERNEL_CONTEXT_MNT_NS:
311 return lttng_add_mnt_ns_to_ctx(ctx);
312 case LTTNG_KERNEL_CONTEXT_NET_NS:
313 return lttng_add_net_ns_to_ctx(ctx);
314 case LTTNG_KERNEL_CONTEXT_PID_NS:
315 return lttng_add_pid_ns_to_ctx(ctx);
316 case LTTNG_KERNEL_CONTEXT_USER_NS:
317 return lttng_add_user_ns_to_ctx(ctx);
318 case LTTNG_KERNEL_CONTEXT_UTS_NS:
319 return lttng_add_uts_ns_to_ctx(ctx);
dc923e75
MJ		 320 case LTTNG_KERNEL_CONTEXT_UID:
321 return lttng_add_uid_to_ctx(ctx);
322 case LTTNG_KERNEL_CONTEXT_EUID:
323 return lttng_add_euid_to_ctx(ctx);
324 case LTTNG_KERNEL_CONTEXT_SUID:
325 return lttng_add_suid_to_ctx(ctx);
326 case LTTNG_KERNEL_CONTEXT_GID:
327 return lttng_add_gid_to_ctx(ctx);
328 case LTTNG_KERNEL_CONTEXT_EGID:
329 return lttng_add_egid_to_ctx(ctx);
330 case LTTNG_KERNEL_CONTEXT_SGID:
331 return lttng_add_sgid_to_ctx(ctx);
332 case LTTNG_KERNEL_CONTEXT_VUID:
333 return lttng_add_vuid_to_ctx(ctx);
334 case LTTNG_KERNEL_CONTEXT_VEUID:
335 return lttng_add_veuid_to_ctx(ctx);
336 case LTTNG_KERNEL_CONTEXT_VSUID:
337 return lttng_add_vsuid_to_ctx(ctx);
338 case LTTNG_KERNEL_CONTEXT_VGID:
339 return lttng_add_vgid_to_ctx(ctx);
340 case LTTNG_KERNEL_CONTEXT_VEGID:
341 return lttng_add_vegid_to_ctx(ctx);
342 case LTTNG_KERNEL_CONTEXT_VSGID:
343 return lttng_add_vsgid_to_ctx(ctx);
876e2e92
MJ		 344 case LTTNG_KERNEL_CONTEXT_TIME_NS:
345 return lttng_add_time_ns_to_ctx(ctx);
8070f5c0
MD		 346 default:
347 return -EINVAL;
348 }
349}
350
ad1c05e1
MD		 351/**
352 * lttng_ioctl - lttng syscall through ioctl
353 *
c0e31d2e 354 * @file: the file
ad1c05e1
MD		 355 * @cmd: the command
356 * @arg: command arg
357 *
358 * This ioctl implements lttng commands:
38d024ae 359 * LTTNG_KERNEL_SESSION
ad1c05e1 360 * Returns a LTTng trace session file descriptor
271b6681
MD		 361 * LTTNG_KERNEL_TRACER_VERSION
362 * Returns the LTTng kernel tracer version
363 * LTTNG_KERNEL_TRACEPOINT_LIST
364 * Returns a file descriptor listing available tracepoints
360f38ea
MD		 365 * LTTNG_KERNEL_WAIT_QUIESCENT
366 * Returns after all previously running probes have completed
42cabb80
MD		 367 * LTTNG_KERNEL_TRACER_ABI_VERSION
368 * Returns the LTTng kernel tracer ABI version
750b05f2
FD		 369 * LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE
370 * Returns a LTTng event notifier group file descriptor
ad1c05e1
MD		 371 *
372 * The returned session will be deleted when its file descriptor is closed.
373 */
374static
c0e31d2e 375long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
ad1c05e1
MD		 376{
377 switch (cmd) {
6dccd6c1 378 case LTTNG_KERNEL_OLD_SESSION:
38d024ae 379 case LTTNG_KERNEL_SESSION:
ad1c05e1 380 return lttng_abi_create_session();
750b05f2
FD		 381 case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE:
382 return lttng_abi_create_event_notifier_group();
6dccd6c1
JD		 383 case LTTNG_KERNEL_OLD_TRACER_VERSION:
384 {
385 struct lttng_kernel_tracer_version v;
386 struct lttng_kernel_old_tracer_version oldv;
387 struct lttng_kernel_old_tracer_version *uversion =
388 (struct lttng_kernel_old_tracer_version __user *) arg;
389
390 lttng_abi_tracer_version(&v);
391 oldv.major = v.major;
392 oldv.minor = v.minor;
393 oldv.patchlevel = v.patchlevel;
394
395 if (copy_to_user(uversion, &oldv, sizeof(oldv)))
396 return -EFAULT;
397 return 0;
398 }
80c16bcf 399 case LTTNG_KERNEL_TRACER_VERSION:
6dccd6c1
JD		 400 {
401 struct lttng_kernel_tracer_version version;
402 struct lttng_kernel_tracer_version *uversion =
403 (struct lttng_kernel_tracer_version __user *) arg;
404
405 lttng_abi_tracer_version(&version);
42cabb80
MD		 406
407 if (copy_to_user(uversion, &version, sizeof(version)))
408 return -EFAULT;
409 return 0;
410 }
411 case LTTNG_KERNEL_TRACER_ABI_VERSION:
412 {
413 struct lttng_kernel_tracer_abi_version version;
414 struct lttng_kernel_tracer_abi_version *uversion =
415 (struct lttng_kernel_tracer_abi_version __user *) arg;
416
417 lttng_abi_tracer_abi_version(&version);
418
6dccd6c1
JD		 419 if (copy_to_user(uversion, &version, sizeof(version)))
420 return -EFAULT;
421 return 0;
422 }
423 case LTTNG_KERNEL_OLD_TRACEPOINT_LIST:
271b6681
MD		 424 case LTTNG_KERNEL_TRACEPOINT_LIST:
425 return lttng_abi_tracepoint_list();
2d2464bd
MD		 426 case LTTNG_KERNEL_SYSCALL_LIST:
427 return lttng_abi_syscall_list();
6dccd6c1 428 case LTTNG_KERNEL_OLD_WAIT_QUIESCENT:
5f7f9078
MD		 429 case LTTNG_KERNEL_WAIT_QUIESCENT:
430 synchronize_trace();
431 return 0;
6dccd6c1
JD		 432 case LTTNG_KERNEL_OLD_CALIBRATE:
433 {
434 struct lttng_kernel_old_calibrate __user *ucalibrate =
435 (struct lttng_kernel_old_calibrate __user *) arg;
436 struct lttng_kernel_old_calibrate old_calibrate;
437 struct lttng_kernel_calibrate calibrate;
438 int ret;
439
440 if (copy_from_user(&old_calibrate, ucalibrate, sizeof(old_calibrate)))
441 return -EFAULT;
442 calibrate.type = old_calibrate.type;
443 ret = lttng_calibrate(&calibrate);
444 if (copy_to_user(ucalibrate, &old_calibrate, sizeof(old_calibrate)))
445 return -EFAULT;
446 return ret;
447 }
57105fc2
MD		 448 case LTTNG_KERNEL_CALIBRATE:
449 {
3db41b2c
MD		 450 struct lttng_kernel_calibrate __user *ucalibrate =
451 (struct lttng_kernel_calibrate __user *) arg;
452 struct lttng_kernel_calibrate calibrate;
57105fc2
MD		 453 int ret;
454
455 if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate)))
456 return -EFAULT;
457 ret = lttng_calibrate(&calibrate);
458 if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate)))
459 return -EFAULT;
460 return ret;
461 }
ad1c05e1
MD		 462 default:
463 return -ENOIOCTLCMD;
464 }
465}
466
059de147
MJ		 467#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
468static const struct proc_ops lttng_proc_ops = {
469 .proc_ioctl = lttng_ioctl,
470#ifdef CONFIG_COMPAT
471 .proc_compat_ioctl = lttng_ioctl,
472#endif /* CONFIG_COMPAT */
473};
474#else
475static const struct file_operations lttng_proc_ops = {
a33c9927 476 .owner = THIS_MODULE,
ad1c05e1
MD		 477 .unlocked_ioctl = lttng_ioctl,
478#ifdef CONFIG_COMPAT
03037b98 479 .compat_ioctl = lttng_ioctl,
059de147 480#endif /* CONFIG_COMPAT */
11b5a3c2 481};
059de147 482#endif
ad1c05e1 483
5dbbdb43 484static
c0e31d2e 485int lttng_abi_create_channel(struct file *session_file,
6dccd6c1 486 struct lttng_kernel_channel *chan_param,
5dbbdb43 487 enum channel_type channel_type)
baf20995 488{
a90917c3 489 struct lttng_session *session = session_file->private_data;
88dfd899 490 const struct file_operations *fops = NULL;
5dbbdb43 491 const char *transport_name;
a90917c3 492 struct lttng_channel *chan;
c0e31d2e 493 struct file *chan_file;
baf20995 494 int chan_fd;
ad1c05e1 495 int ret = 0;
baf20995 496
4ac10b76 497 chan_fd = lttng_get_unused_fd();
baf20995
MD		 498 if (chan_fd < 0) {
499 ret = chan_fd;
500 goto fd_error;
501 }
88dfd899
MD		 502 switch (channel_type) {
503 case PER_CPU_CHANNEL:
504 fops = &lttng_channel_fops;
505 break;
506 case METADATA_CHANNEL:
507 fops = &lttng_metadata_fops;
508 break;
509 }
2470a237 510
c0e31d2e 511 chan_file = anon_inode_getfile("[lttng_channel]",
88dfd899 512 fops,
03037b98 513 NULL, O_RDWR);
c0e31d2e
MD		 514 if (IS_ERR(chan_file)) {
515 ret = PTR_ERR(chan_file);
baf20995
MD		 516 goto file_error;
517 }
5dbbdb43
MD		 518 switch (channel_type) {
519 case PER_CPU_CHANNEL:
6dccd6c1
JD		 520 if (chan_param->output == LTTNG_KERNEL_SPLICE) {
521 transport_name = chan_param->overwrite ?
96ba7208 522 "relay-overwrite" : "relay-discard";
6dccd6c1
JD		 523 } else if (chan_param->output == LTTNG_KERNEL_MMAP) {
524 transport_name = chan_param->overwrite ?
96ba7208
JD		 525 "relay-overwrite-mmap" : "relay-discard-mmap";
526 } else {
527 return -EINVAL;
528 }
5dbbdb43 529 break;
5dbbdb43 530 case METADATA_CHANNEL:
6dccd6c1 531 if (chan_param->output == LTTNG_KERNEL_SPLICE)
96ba7208 532 transport_name = "relay-metadata";
6dccd6c1 533 else if (chan_param->output == LTTNG_KERNEL_MMAP)
96ba7208
JD		 534 transport_name = "relay-metadata-mmap";
535 else
536 return -EINVAL;
5dbbdb43
MD		 537 break;
538 default:
539 transport_name = "<unknown>";
540 break;
541 }
98d7281c
MJ		 542 if (!atomic_long_add_unless(&session_file->f_count, 1, LONG_MAX)) {
543 ret = -EOVERFLOW;
9c1f4643
MD		 544 goto refcount_error;
545 }
03037b98
MD		 546 /*
547 * We tolerate no failure path after channel creation. It will stay
548 * invariant for the rest of the session.
549 */
a90917c3 550 chan = lttng_channel_create(session, transport_name, NULL,
6dccd6c1
JD		 551 chan_param->subbuf_size,
552 chan_param->num_subbuf,
553 chan_param->switch_timer_interval,
d83004aa
JD		 554 chan_param->read_timer_interval,
555 channel_type);
03037b98 556 if (!chan) {
f3d01b96 557 ret = -EINVAL;
03037b98
MD		 558 goto chan_error;
559 }
11b5a3c2 560 chan->file = chan_file;
c0e31d2e
MD		 561 chan_file->private_data = chan;
562 fd_install(chan_fd, chan_file);
ad1c05e1 563
baf20995
MD		 564 return chan_fd;
565
03037b98 566chan_error:
9c1f4643
MD		 567 atomic_long_dec(&session_file->f_count);
568refcount_error:
c0e31d2e 569 fput(chan_file);
baf20995
MD		 570file_error:
571 put_unused_fd(chan_fd);
572fd_error:
baf20995
MD		 573 return ret;
574}
575
7f859fbf
JR		 576static
577int lttng_abi_session_set_name(struct lttng_session *session,
578 struct lttng_kernel_session_name *name)
579{
580 size_t len;
581
582 len = strnlen(name->name, LTTNG_KERNEL_SESSION_NAME_LEN);
583
584 if (len == LTTNG_KERNEL_SESSION_NAME_LEN) {
585 /* Name is too long/malformed */
586 return -EINVAL;
587 }
588
589 strcpy(session->name, name->name);
590 return 0;
591}
592
1c88f269
JR		 593static
594int lttng_abi_session_set_creation_time(struct lttng_session *session,
595 struct lttng_kernel_session_creation_time *time)
596{
597 size_t len;
598
599 len = strnlen(time->iso8601, LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN);
600
601 if (len == LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN) {
602 /* Time is too long/malformed */
603 return -EINVAL;
604 }
605
606 strcpy(session->creation_time, time->iso8601);
607 return 0;
608}
609
99f52fcc
FD		 610static
611int lttng_counter_release(struct inode *inode, struct file *file)
612{
613 struct lttng_counter *counter = file->private_data;
614
615 if (counter) {
616 /*
617 * Do not destroy the counter itself. Wait of the owner
618 * (event_notifier group) to be destroyed.
619 */
620 fput(counter->owner);
621 }
622
623 return 0;
624}
625
626static
627long lttng_counter_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
628{
629 struct lttng_counter *counter = file->private_data;
630 size_t indexes[LTTNG_KERNEL_COUNTER_DIMENSION_MAX] = { 0 };
631 int i;
632
633 switch (cmd) {
634 case LTTNG_KERNEL_COUNTER_READ:
635 {
636 struct lttng_kernel_counter_read local_counter_read;
637 struct lttng_kernel_counter_read __user *ucounter_read =
638 (struct lttng_kernel_counter_read __user *) arg;
639 bool overflow, underflow;
640 int64_t value;
641 int32_t cpu;
642 int ret;
643
644 if (copy_from_user(&local_counter_read, ucounter_read,
645 sizeof(local_counter_read)))
646 return -EFAULT;
647 if (validate_zeroed_padding(local_counter_read.padding,
648 sizeof(local_counter_read.padding)))
649 return -EINVAL;
650
651 /* Cast all indexes into size_t. */
652 for (i = 0; i < local_counter_read.index.number_dimensions; i++)
653 indexes[i] = (size_t) local_counter_read.index.dimension_indexes[i];
654 cpu = local_counter_read.cpu;
655
656 ret = lttng_kernel_counter_read(counter, indexes, cpu, &value,
657 &overflow, &underflow);
658 if (ret)
659 return ret;
660 local_counter_read.value.value = value;
661 local_counter_read.value.overflow = overflow;
662 local_counter_read.value.underflow = underflow;
663
664 if (copy_to_user(&ucounter_read->value, &local_counter_read.value,
665 sizeof(local_counter_read.value)))
666 return -EFAULT;
667
668 return 0;
669 }
670 case LTTNG_KERNEL_COUNTER_AGGREGATE:
671 {
672 struct lttng_kernel_counter_aggregate local_counter_aggregate;
673 struct lttng_kernel_counter_aggregate __user *ucounter_aggregate =
674 (struct lttng_kernel_counter_aggregate __user *) arg;
675 bool overflow, underflow;
676 int64_t value;
677 int ret;
678
679 if (copy_from_user(&local_counter_aggregate, ucounter_aggregate,
680 sizeof(local_counter_aggregate)))
681 return -EFAULT;
682 if (validate_zeroed_padding(local_counter_aggregate.padding,
683 sizeof(local_counter_aggregate.padding)))
684 return -EINVAL;
685
686 /* Cast all indexes into size_t. */
687 for (i = 0; i < local_counter_aggregate.index.number_dimensions; i++)
688 indexes[i] = (size_t) local_counter_aggregate.index.dimension_indexes[i];
689
690 ret = lttng_kernel_counter_aggregate(counter, indexes, &value,
691 &overflow, &underflow);
692 if (ret)
693 return ret;
694 local_counter_aggregate.value.value = value;
695 local_counter_aggregate.value.overflow = overflow;
696 local_counter_aggregate.value.underflow = underflow;
697
698 if (copy_to_user(&ucounter_aggregate->value, &local_counter_aggregate.value,
699 sizeof(local_counter_aggregate.value)))
700 return -EFAULT;
701
702 return 0;
703 }
704 case LTTNG_KERNEL_COUNTER_CLEAR:
705 {
706 struct lttng_kernel_counter_clear local_counter_clear;
707 struct lttng_kernel_counter_clear __user *ucounter_clear =
708 (struct lttng_kernel_counter_clear __user *) arg;
709
710 if (copy_from_user(&local_counter_clear, ucounter_clear,
711 sizeof(local_counter_clear)))
712 return -EFAULT;
713 if (validate_zeroed_padding(local_counter_clear.padding,
714 sizeof(local_counter_clear.padding)))
715 return -EINVAL;
716
717 /* Cast all indexes into size_t. */
718 for (i = 0; i < local_counter_clear.index.number_dimensions; i++)
719 indexes[i] = (size_t) local_counter_clear.index.dimension_indexes[i];
720
721 return lttng_kernel_counter_clear(counter, indexes);
722 }
723 default:
724 WARN_ON_ONCE(1);
725 return -ENOSYS;
726 }
727}
728
729static const struct file_operations lttng_counter_fops = {
730 .owner = THIS_MODULE,
731 .release = lttng_counter_release,
732 .unlocked_ioctl = lttng_counter_ioctl,
733#ifdef CONFIG_COMPAT
734 .compat_ioctl = lttng_counter_ioctl,
735#endif
736};
737
738
d1f652f8
MD		 739static
740enum tracker_type get_tracker_type(struct lttng_kernel_tracker_args *tracker)
741{
742 switch (tracker->type) {
743 case LTTNG_KERNEL_TRACKER_PID:
744 return TRACKER_PID;
745 case LTTNG_KERNEL_TRACKER_VPID:
746 return TRACKER_VPID;
747 case LTTNG_KERNEL_TRACKER_UID:
748 return TRACKER_UID;
749 case LTTNG_KERNEL_TRACKER_VUID:
750 return TRACKER_VUID;
751 case LTTNG_KERNEL_TRACKER_GID:
752 return TRACKER_GID;
753 case LTTNG_KERNEL_TRACKER_VGID:
754 return TRACKER_VGID;
755 default:
756 return TRACKER_UNKNOWN;
757 }
758}
759
baf20995 760/**
ad1c05e1 761 * lttng_session_ioctl - lttng session fd ioctl
baf20995 762 *
c0e31d2e 763 * @file: the file
baf20995
MD		 764 * @cmd: the command
765 * @arg: command arg
766 *
767 * This ioctl implements lttng commands:
38d024ae 768 * LTTNG_KERNEL_CHANNEL
baf20995 769 * Returns a LTTng channel file descriptor
e64957da
MD		 770 * LTTNG_KERNEL_ENABLE
771 * Enables tracing for a session (weak enable)
772 * LTTNG_KERNEL_DISABLE
773 * Disables tracing for a session (strong disable)
8070f5c0
MD		 774 * LTTNG_KERNEL_METADATA
775 * Returns a LTTng metadata file descriptor
e0130fab 776 * LTTNG_KERNEL_SESSION_TRACK_PID
d1f652f8 777 * Add PID to session PID tracker
e0130fab 778 * LTTNG_KERNEL_SESSION_UNTRACK_PID
d1f652f8
MD		 779 * Remove PID from session PID tracker
780 * LTTNG_KERNEL_SESSION_TRACK_ID
781 * Add ID to tracker
782 * LTTNG_KERNEL_SESSION_UNTRACK_ID
783 * Remove ID from tracker
ad1c05e1
MD		 784 *
785 * The returned channel will be deleted when its file descriptor is closed.
786 */
787static
c0e31d2e 788long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
ad1c05e1 789{
a90917c3 790 struct lttng_session *session = file->private_data;
2d4c4d15
MD		 791 struct lttng_kernel_channel chan_param;
792 struct lttng_kernel_old_channel old_chan_param;
c0e31d2e 793
ad1c05e1 794 switch (cmd) {
6dccd6c1
JD		 795 case LTTNG_KERNEL_OLD_CHANNEL:
796 {
6dccd6c1
JD		 797 if (copy_from_user(&old_chan_param,
798 (struct lttng_kernel_old_channel __user *) arg,
799 sizeof(struct lttng_kernel_old_channel)))
800 return -EFAULT;
801 chan_param.overwrite = old_chan_param.overwrite;
802 chan_param.subbuf_size = old_chan_param.subbuf_size;
803 chan_param.num_subbuf = old_chan_param.num_subbuf;
804 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
805 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
806 chan_param.output = old_chan_param.output;
807
808 return lttng_abi_create_channel(file, &chan_param,
809 PER_CPU_CHANNEL);
810 }
38d024ae 811 case LTTNG_KERNEL_CHANNEL:
6dccd6c1 812 {
6dccd6c1 813 if (copy_from_user(&chan_param,
38d024ae 814 (struct lttng_kernel_channel __user *) arg,
6dccd6c1
JD		 815 sizeof(struct lttng_kernel_channel)))
816 return -EFAULT;
817 return lttng_abi_create_channel(file, &chan_param,
5dbbdb43 818 PER_CPU_CHANNEL);
6dccd6c1
JD		 819 }
820 case LTTNG_KERNEL_OLD_SESSION_START:
821 case LTTNG_KERNEL_OLD_ENABLE:
38d024ae 822 case LTTNG_KERNEL_SESSION_START:
e64957da 823 case LTTNG_KERNEL_ENABLE:
a90917c3 824 return lttng_session_enable(session);
6dccd6c1
JD		 825 case LTTNG_KERNEL_OLD_SESSION_STOP:
826 case LTTNG_KERNEL_OLD_DISABLE:
38d024ae 827 case LTTNG_KERNEL_SESSION_STOP:
e64957da 828 case LTTNG_KERNEL_DISABLE:
a90917c3 829 return lttng_session_disable(session);
6dccd6c1
JD		 830 case LTTNG_KERNEL_OLD_METADATA:
831 {
6dccd6c1
JD		 832 if (copy_from_user(&old_chan_param,
833 (struct lttng_kernel_old_channel __user *) arg,
834 sizeof(struct lttng_kernel_old_channel)))
835 return -EFAULT;
836 chan_param.overwrite = old_chan_param.overwrite;
837 chan_param.subbuf_size = old_chan_param.subbuf_size;
838 chan_param.num_subbuf = old_chan_param.num_subbuf;
839 chan_param.switch_timer_interval = old_chan_param.switch_timer_interval;
840 chan_param.read_timer_interval = old_chan_param.read_timer_interval;
841 chan_param.output = old_chan_param.output;
842
843 return lttng_abi_create_channel(file, &chan_param,
844 METADATA_CHANNEL);
845 }
38d024ae 846 case LTTNG_KERNEL_METADATA:
6dccd6c1 847 {
6dccd6c1
JD		 848 if (copy_from_user(&chan_param,
849 (struct lttng_kernel_channel __user *) arg,
850 sizeof(struct lttng_kernel_channel)))
851 return -EFAULT;
852 return lttng_abi_create_channel(file, &chan_param,
5dbbdb43 853 METADATA_CHANNEL);
6dccd6c1 854 }
e0130fab 855 case LTTNG_KERNEL_SESSION_TRACK_PID:
d1f652f8 856 return lttng_session_track_id(session, TRACKER_PID, (int) arg);
e0130fab 857 case LTTNG_KERNEL_SESSION_UNTRACK_PID:
d1f652f8
MD		 858 return lttng_session_untrack_id(session, TRACKER_PID, (int) arg);
859 case LTTNG_KERNEL_SESSION_TRACK_ID:
860 {
861 struct lttng_kernel_tracker_args tracker;
862 enum tracker_type tracker_type;
863
864 if (copy_from_user(&tracker,
865 (struct lttng_kernel_tracker_args __user *) arg,
866 sizeof(struct lttng_kernel_tracker_args)))
867 return -EFAULT;
868 tracker_type = get_tracker_type(&tracker);
869 if (tracker_type == TRACKER_UNKNOWN)
870 return -EINVAL;
871 return lttng_session_track_id(session, tracker_type, tracker.id);
872 }
873 case LTTNG_KERNEL_SESSION_UNTRACK_ID:
874 {
875 struct lttng_kernel_tracker_args tracker;
876 enum tracker_type tracker_type;
877
878 if (copy_from_user(&tracker,
879 (struct lttng_kernel_tracker_args __user *) arg,
880 sizeof(struct lttng_kernel_tracker_args)))
881 return -EFAULT;
882 tracker_type = get_tracker_type(&tracker);
883 if (tracker_type == TRACKER_UNKNOWN)
884 return -EINVAL;
885 return lttng_session_untrack_id(session, tracker_type,
886 tracker.id);
887 }
7e6f9ef6 888 case LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS:
d1f652f8
MD		 889 return lttng_session_list_tracker_ids(session, TRACKER_PID);
890 case LTTNG_KERNEL_SESSION_LIST_TRACKER_IDS:
891 {
892 struct lttng_kernel_tracker_args tracker;
893 enum tracker_type tracker_type;
894
895 if (copy_from_user(&tracker,
896 (struct lttng_kernel_tracker_args __user *) arg,
897 sizeof(struct lttng_kernel_tracker_args)))
898 return -EFAULT;
899 tracker_type = get_tracker_type(&tracker);
900 if (tracker_type == TRACKER_UNKNOWN)
901 return -EINVAL;
902 return lttng_session_list_tracker_ids(session, tracker_type);
903 }
9616f0bf
JD		 904 case LTTNG_KERNEL_SESSION_METADATA_REGEN:
905 return lttng_session_metadata_regenerate(session);
601252cf
MD		 906 case LTTNG_KERNEL_SESSION_STATEDUMP:
907 return lttng_session_statedump(session);
7f859fbf
JR		 908 case LTTNG_KERNEL_SESSION_SET_NAME:
909 {
910 struct lttng_kernel_session_name name;
911
912 if (copy_from_user(&name,
913 (struct lttng_kernel_session_name __user *) arg,
914 sizeof(struct lttng_kernel_session_name)))
915 return -EFAULT;
916 return lttng_abi_session_set_name(session, &name);
917 }
1c88f269
JR		 918 case LTTNG_KERNEL_SESSION_SET_CREATION_TIME:
919 {
920 struct lttng_kernel_session_creation_time time;
921
922 if (copy_from_user(&time,
923 (struct lttng_kernel_session_creation_time __user *) arg,
924 sizeof(struct lttng_kernel_session_creation_time)))
925 return -EFAULT;
926 return lttng_abi_session_set_creation_time(session, &time);
927 }
ad1c05e1
MD		 928 default:
929 return -ENOIOCTLCMD;
930 }
931}
932
03037b98
MD		 933/*
934 * Called when the last file reference is dropped.
935 *
936 * Big fat note: channels and events are invariant for the whole session after
937 * their creation. So this session destruction also destroys all channel and
938 * event structures specific to this session (they are not destroyed when their
939 * individual file is released).
940 */
ad1c05e1 941static
03037b98 942int lttng_session_release(struct inode *inode, struct file *file)
ad1c05e1 943{
a90917c3 944 struct lttng_session *session = file->private_data;
c269fff4
MD		 945
946 if (session)
a90917c3 947 lttng_session_destroy(session);
11b5a3c2 948 return 0;
ad1c05e1 949}
ad1c05e1
MD		 950
951static const struct file_operations lttng_session_fops = {
a33c9927 952 .owner = THIS_MODULE,
03037b98 953 .release = lttng_session_release,
ad1c05e1
MD		 954 .unlocked_ioctl = lttng_session_ioctl,
955#ifdef CONFIG_COMPAT
03037b98 956 .compat_ioctl = lttng_session_ioctl,
ad1c05e1 957#endif
11b5a3c2 958};
ad1c05e1 959
db2511b4
MD		 960/*
961 * When encountering empty buffer, flush current sub-buffer if non-empty
962 * and retry (if new data available to read after flush).
963 */
964static
965ssize_t lttng_event_notifier_group_notif_read(struct file *filp, char __user *user_buf,
966 size_t count, loff_t *ppos)
967{
968 struct lttng_event_notifier_group *event_notifier_group = filp->private_data;
969 struct channel *chan = event_notifier_group->chan;
970 struct lib_ring_buffer *buf = event_notifier_group->buf;
971 ssize_t read_count = 0, len;
972 size_t read_offset;
973
974 might_sleep();
975 if (!lttng_access_ok(VERIFY_WRITE, user_buf, count))
976 return -EFAULT;
977
978 /* Finish copy of previous record */
979 if (*ppos != 0) {
980 if (read_count < count) {
981 len = chan->iter.len_left;
982 read_offset = *ppos;
983 goto skip_get_next;
984 }
985 }
986
987 while (read_count < count) {
988 size_t copy_len, space_left;
989
990 len = lib_ring_buffer_get_next_record(chan, buf);
991len_test:
992 if (len < 0) {
993 /*
994 * Check if buffer is finalized (end of file).
995 */
996 if (len == -ENODATA) {
997 /* A 0 read_count will tell about end of file */
998 goto nodata;
999 }
1000 if (filp->f_flags & O_NONBLOCK) {
1001 if (!read_count)
1002 read_count = -EAGAIN;
1003 goto nodata;
1004 } else {
1005 int error;
1006
1007 /*
1008 * No data available at the moment, return what
1009 * we got.
1010 */
1011 if (read_count)
1012 goto nodata;
1013
1014 /*
1015 * Wait for returned len to be >= 0 or -ENODATA.
1016 */
1017 error = wait_event_interruptible(
1018 event_notifier_group->read_wait,
1019 ((len = lib_ring_buffer_get_next_record(
1020 chan, buf)), len != -EAGAIN));
1021 CHAN_WARN_ON(chan, len == -EBUSY);
1022 if (error) {
1023 read_count = error;
1024 goto nodata;
1025 }
1026 CHAN_WARN_ON(chan, len < 0 && len != -ENODATA);
1027 goto len_test;
1028 }
1029 }
1030 read_offset = buf->iter.read_offset;
1031skip_get_next:
1032 space_left = count - read_count;
1033 if (len <= space_left) {
1034 copy_len = len;
1035 chan->iter.len_left = 0;
1036 *ppos = 0;
1037 } else {
1038 copy_len = space_left;
1039 chan->iter.len_left = len - copy_len;
1040 *ppos = read_offset + copy_len;
1041 }
1042 if (__lib_ring_buffer_copy_to_user(&buf->backend, read_offset,
1043 &user_buf[read_count],
1044 copy_len)) {
1045 /*
1046 * Leave the len_left and ppos values at their current
1047 * state, as we currently have a valid event to read.
1048 */
1049 return -EFAULT;
1050 }
1051 read_count += copy_len;
1052 }
31c02fb7 1053 goto put_record;
db2511b4
MD		 1054
1055nodata:
1056 *ppos = 0;
1057 chan->iter.len_left = 0;
31c02fb7
MD		 1058
1059put_record:
1060 lib_ring_buffer_put_current_record(buf);
db2511b4
MD		 1061 return read_count;
1062}
1063
1064/*
1065 * If the ring buffer is non empty (even just a partial subbuffer), return that
1066 * there is data available. Perform a ring buffer flush if we encounter a
1067 * non-empty ring buffer which does not have any consumeable subbuffer available.
1068 */
1069static
1070unsigned int lttng_event_notifier_group_notif_poll(struct file *filp,
1071 poll_table *wait)
1072{
1073 unsigned int mask = 0;
1074 struct lttng_event_notifier_group *event_notifier_group = filp->private_data;
1075 struct channel *chan = event_notifier_group->chan;
1076 struct lib_ring_buffer *buf = event_notifier_group->buf;
1077 const struct lib_ring_buffer_config *config = &chan->backend.config;
1078 int finalized, disabled;
1079 unsigned long consumed, offset;
18f12d55 1080 size_t subbuffer_header_size = config->cb.subbuffer_header_size();
db2511b4
MD		 1081
1082 if (filp->f_mode & FMODE_READ) {
1083 poll_wait_set_exclusive(wait);
1084 poll_wait(filp, &event_notifier_group->read_wait, wait);
1085
1086 finalized = lib_ring_buffer_is_finalized(config, buf);
1087 disabled = lib_ring_buffer_channel_is_disabled(chan);
1088
1089 /*
1090 * lib_ring_buffer_is_finalized() contains a smp_rmb() ordering
1091 * finalized load before offsets loads.
1092 */
1093 WARN_ON(atomic_long_read(&buf->active_readers) != 1);
1094retry:
1095 if (disabled)
1096 return POLLERR;
1097
1098 offset = lib_ring_buffer_get_offset(config, buf);
1099 consumed = lib_ring_buffer_get_consumed(config, buf);
1100
1101 /*
1102 * If there is no buffer available to consume.
1103 */
1104 if (subbuf_trunc(offset, chan) - subbuf_trunc(consumed, chan) == 0) {
1105 /*
1106 * If there is a non-empty subbuffer, flush and try again.
1107 */
18f12d55 1108 if (subbuf_offset(offset, chan) > subbuffer_header_size) {
db2511b4
MD		 1109 lib_ring_buffer_switch_remote(buf);
1110 goto retry;
1111 }
1112
1113 if (finalized)
1114 return POLLHUP;
1115 else {
1116 /*
1117 * The memory barriers
1118 * __wait_event()/wake_up_interruptible() take
1119 * care of "raw_spin_is_locked" memory ordering.
1120 */
1121 if (raw_spin_is_locked(&buf->raw_tick_nohz_spinlock))
1122 goto retry;
1123 else
1124 return 0;
1125 }
1126 } else {
1127 if (subbuf_trunc(offset, chan) - subbuf_trunc(consumed, chan)
1128 >= chan->backend.buf_size)
1129 return POLLPRI | POLLRDBAND;
1130 else
1131 return POLLIN | POLLRDNORM;
1132 }
1133 }
1134
1135 return mask;
1136}
1137
1138/**
1139 * lttng_event_notifier_group_notif_open - event_notifier ring buffer open file operation
1140 * @inode: opened inode
1141 * @file: opened file
1142 *
1143 * Open implementation. Makes sure only one open instance of a buffer is
1144 * done at a given moment.
1145 */
1146static int lttng_event_notifier_group_notif_open(struct inode *inode, struct file *file)
1147{
1148 struct lttng_event_notifier_group *event_notifier_group = inode->i_private;
1149 struct lib_ring_buffer *buf = event_notifier_group->buf;
1150
1151 file->private_data = event_notifier_group;
1152 return lib_ring_buffer_open(inode, file, buf);
1153}
1154
1155/**
1156 * lttng_event_notifier_group_notif_release - event_notifier ring buffer release file operation
1157 * @inode: opened inode
1158 * @file: opened file
1159 *
1160 * Release implementation.
1161 */
1162static int lttng_event_notifier_group_notif_release(struct inode *inode, struct file *file)
1163{
1164 struct lttng_event_notifier_group *event_notifier_group = file->private_data;
1165 struct lib_ring_buffer *buf = event_notifier_group->buf;
1166 int ret;
1167
1168 ret = lib_ring_buffer_release(inode, file, buf);
1169 if (ret)
1170 return ret;
1171 fput(event_notifier_group->file);
1172 return 0;
1173}
1174
21f58fb7
FD		 1175static const struct file_operations lttng_event_notifier_group_notif_fops = {
1176 .owner = THIS_MODULE,
db2511b4
MD		 1177 .open = lttng_event_notifier_group_notif_open,
1178 .release = lttng_event_notifier_group_notif_release,
1179 .read = lttng_event_notifier_group_notif_read,
1180 .poll = lttng_event_notifier_group_notif_poll,
21f58fb7
FD		 1181};
1182
d83004aa
JD		 1183/**
1184 * lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
1185 * @filp: the file
1186 * @wait: poll table
1187 *
1188 * Handles the poll operations for the metadata channels.
1189 */
ad1c05e1 1190static
d83004aa
JD		 1191unsigned int lttng_metadata_ring_buffer_poll(struct file *filp,
1192 poll_table *wait)
1193{
1194 struct lttng_metadata_stream *stream = filp->private_data;
1195 struct lib_ring_buffer *buf = stream->priv;
1196 int finalized;
1197 unsigned int mask = 0;
1198
1199 if (filp->f_mode & FMODE_READ) {
1200 poll_wait_set_exclusive(wait);
1201 poll_wait(filp, &stream->read_wait, wait);
1202
1203 finalized = stream->finalized;
1204
1205 /*
1206 * lib_ring_buffer_is_finalized() contains a smp_rmb()
1207 * ordering finalized load before offsets loads.
1208 */
1209 WARN_ON(atomic_long_read(&buf->active_readers) != 1);
1210
1211 if (finalized)
1212 mask |= POLLHUP;
1213
92d9f5e6 1214 mutex_lock(&stream->metadata_cache->lock);
d83004aa 1215 if (stream->metadata_cache->metadata_written >
f613e3e6 1216 stream->metadata_out)
d83004aa 1217 mask |= POLLIN;
92d9f5e6 1218 mutex_unlock(&stream->metadata_cache->lock);
d83004aa
JD		 1219 }
1220
1221 return mask;
1222}
1223
f613e3e6
MD		 1224static
1225void lttng_metadata_ring_buffer_ioctl_put_next_subbuf(struct file *filp,
1226 unsigned int cmd, unsigned long arg)
1227{
1228 struct lttng_metadata_stream *stream = filp->private_data;
1229
1230 stream->metadata_out = stream->metadata_in;
1231}
1232
d1344afa
JD		 1233/*
1234 * Reset the counter of how much metadata has been consumed to 0. That way,
1235 * the consumer receives the content of the metadata cache unchanged. This is
1236 * different from the metadata_regenerate where the offset from epoch is
1237 * resampled, here we want the exact same content as the last time the metadata
1238 * was generated. This command is only possible if all the metadata written
1239 * in the cache has been output to the metadata stream to avoid corrupting the
1240 * metadata file.
1241 *
1242 * Return 0 on success, a negative value on error.
1243 */
1244static
1245int lttng_metadata_cache_dump(struct lttng_metadata_stream *stream)
1246{
1247 int ret;
1248 struct lttng_metadata_cache *cache = stream->metadata_cache;
1249
1250 mutex_lock(&cache->lock);
1251 if (stream->metadata_out != cache->metadata_written) {
1252 ret = -EBUSY;
1253 goto end;
1254 }
1255 stream->metadata_out = 0;
1256 stream->metadata_in = 0;
1257 wake_up_interruptible(&stream->read_wait);
1258 ret = 0;
1259
1260end:
1261 mutex_unlock(&cache->lock);
1262 return ret;
1263}
1264
d83004aa
JD		 1265static
1266long lttng_metadata_ring_buffer_ioctl(struct file *filp,
1267 unsigned int cmd, unsigned long arg)
1268{
1269 int ret;
1270 struct lttng_metadata_stream *stream = filp->private_data;
1271 struct lib_ring_buffer *buf = stream->priv;
8b97fd42
MD		 1272 unsigned int rb_cmd;
1273 bool coherent;
1274
1275 if (cmd == RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK)
1276 rb_cmd = RING_BUFFER_GET_NEXT_SUBBUF;
1277 else
1278 rb_cmd = cmd;
d83004aa
JD		 1279
1280 switch (cmd) {
d83004aa
JD		 1281 case RING_BUFFER_GET_NEXT_SUBBUF:
1282 {
35097f36
JD		 1283 struct lttng_metadata_stream *stream = filp->private_data;
1284 struct lib_ring_buffer *buf = stream->priv;
1285 struct channel *chan = buf->backend.chan;
1286
8b97fd42 1287 ret = lttng_metadata_output_channel(stream, chan, NULL);
35097f36
JD		 1288 if (ret > 0) {
1289 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1290 ret = 0;
1291 } else if (ret < 0)
d83004aa
JD		 1292 goto err;
1293 break;
1294 }
f613e3e6
MD		 1295 case RING_BUFFER_GET_SUBBUF:
1296 {
1297 /*
1298 * Random access is not allowed for metadata channel.
1299 */
1300 return -ENOSYS;
1301 }
c6f05468 1302 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
35097f36
JD		 1303 case RING_BUFFER_FLUSH:
1304 {
1305 struct lttng_metadata_stream *stream = filp->private_data;
1306 struct lib_ring_buffer *buf = stream->priv;
1307 struct channel *chan = buf->backend.chan;
1308
1309 /*
1310 * Before doing the actual ring buffer flush, write up to one
1311 * packet of metadata in the ring buffer.
1312 */
8b97fd42 1313 ret = lttng_metadata_output_channel(stream, chan, NULL);
35097f36
JD		 1314 if (ret < 0)
1315 goto err;
1316 break;
1317 }
9616f0bf
JD		 1318 case RING_BUFFER_GET_METADATA_VERSION:
1319 {
1320 struct lttng_metadata_stream *stream = filp->private_data;
1321
1322 return put_u64(stream->version, arg);
1323 }
d1344afa
JD		 1324 case RING_BUFFER_METADATA_CACHE_DUMP:
1325 {
1326 struct lttng_metadata_stream *stream = filp->private_data;
1327
1328 return lttng_metadata_cache_dump(stream);
1329 }
8b97fd42
MD		 1330 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1331 {
1332 struct lttng_metadata_stream *stream = filp->private_data;
1333 struct lib_ring_buffer *buf = stream->priv;
1334 struct channel *chan = buf->backend.chan;
1335
1336 ret = lttng_metadata_output_channel(stream, chan, &coherent);
1337 if (ret > 0) {
1338 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1339 ret = 0;
1340 } else if (ret < 0) {
1341 goto err;
1342 }
1343 break;
1344 }
d83004aa
JD		 1345 default:
1346 break;
1347 }
f613e3e6
MD		 1348 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
1349
d83004aa 1350 /* Performing lib ring buffer ioctl after our own. */
8b97fd42 1351 ret = lib_ring_buffer_ioctl(filp, rb_cmd, arg, buf);
f613e3e6
MD		 1352 if (ret < 0)
1353 goto err;
d83004aa 1354
f613e3e6
MD		 1355 switch (cmd) {
1356 case RING_BUFFER_PUT_NEXT_SUBBUF:
1357 {
1358 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
1359 cmd, arg);
1360 break;
1361 }
8b97fd42
MD		 1362 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1363 {
1364 return put_u32(coherent, arg);
1365 }
f613e3e6
MD		 1366 default:
1367 break;
1368 }
d83004aa
JD		 1369err:
1370 return ret;
1371}
1372
aeb9064d 1373#ifdef CONFIG_COMPAT
d83004aa
JD		 1374static
1375long lttng_metadata_ring_buffer_compat_ioctl(struct file *filp,
1376 unsigned int cmd, unsigned long arg)
1377{
1378 int ret;
1379 struct lttng_metadata_stream *stream = filp->private_data;
1380 struct lib_ring_buffer *buf = stream->priv;
8b97fd42
MD		 1381 unsigned int rb_cmd;
1382 bool coherent;
1383
1384 if (cmd == RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK)
1385 rb_cmd = RING_BUFFER_GET_NEXT_SUBBUF;
1386 else
1387 rb_cmd = cmd;
d83004aa
JD		 1388
1389 switch (cmd) {
d83004aa
JD		 1390 case RING_BUFFER_GET_NEXT_SUBBUF:
1391 {
35097f36
JD		 1392 struct lttng_metadata_stream *stream = filp->private_data;
1393 struct lib_ring_buffer *buf = stream->priv;
1394 struct channel *chan = buf->backend.chan;
1395
8b97fd42 1396 ret = lttng_metadata_output_channel(stream, chan, NULL);
35097f36
JD		 1397 if (ret > 0) {
1398 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1399 ret = 0;
1400 } else if (ret < 0)
d83004aa
JD		 1401 goto err;
1402 break;
1403 }
f613e3e6
MD		 1404 case RING_BUFFER_GET_SUBBUF:
1405 {
1406 /*
1407 * Random access is not allowed for metadata channel.
1408 */
1409 return -ENOSYS;
1410 }
c6f05468 1411 case RING_BUFFER_FLUSH_EMPTY: /* Fall-through. */
96c55c2f
MD		 1412 case RING_BUFFER_FLUSH:
1413 {
1414 struct lttng_metadata_stream *stream = filp->private_data;
1415 struct lib_ring_buffer *buf = stream->priv;
1416 struct channel *chan = buf->backend.chan;
1417
1418 /*
1419 * Before doing the actual ring buffer flush, write up to one
1420 * packet of metadata in the ring buffer.
1421 */
8b97fd42 1422 ret = lttng_metadata_output_channel(stream, chan, NULL);
96c55c2f
MD		 1423 if (ret < 0)
1424 goto err;
1425 break;
1426 }
1427 case RING_BUFFER_GET_METADATA_VERSION:
1428 {
1429 struct lttng_metadata_stream *stream = filp->private_data;
1430
1431 return put_u64(stream->version, arg);
1432 }
d1344afa
JD		 1433 case RING_BUFFER_METADATA_CACHE_DUMP:
1434 {
1435 struct lttng_metadata_stream *stream = filp->private_data;
1436
1437 return lttng_metadata_cache_dump(stream);
1438 }
8b97fd42
MD		 1439 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1440 {
1441 struct lttng_metadata_stream *stream = filp->private_data;
1442 struct lib_ring_buffer *buf = stream->priv;
1443 struct channel *chan = buf->backend.chan;
1444
1445 ret = lttng_metadata_output_channel(stream, chan, &coherent);
1446 if (ret > 0) {
1447 lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
1448 ret = 0;
1449 } else if (ret < 0) {
1450 goto err;
1451 }
1452 break;
1453 }
d83004aa
JD		 1454 default:
1455 break;
1456 }
f613e3e6
MD		 1457 /* PUT_SUBBUF is the one from lib ring buffer, unmodified. */
1458
d83004aa 1459 /* Performing lib ring buffer ioctl after our own. */
8b97fd42 1460 ret = lib_ring_buffer_compat_ioctl(filp, rb_cmd, arg, buf);
f613e3e6
MD		 1461 if (ret < 0)
1462 goto err;
d83004aa 1463
f613e3e6
MD		 1464 switch (cmd) {
1465 case RING_BUFFER_PUT_NEXT_SUBBUF:
1466 {
1467 lttng_metadata_ring_buffer_ioctl_put_next_subbuf(filp,
1468 cmd, arg);
1469 break;
1470 }
8b97fd42
MD		 1471 case RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK:
1472 {
1473 return put_u32(coherent, arg);
1474 }
f613e3e6
MD		 1475 default:
1476 break;
1477 }
d83004aa
JD		 1478err:
1479 return ret;
1480}
aeb9064d 1481#endif
d83004aa 1482
b3b8072b
MD		 1483/*
1484 * This is not used by anonymous file descriptors. This code is left
1485 * there if we ever want to implement an inode with open() operation.
1486 */
d83004aa
JD		 1487static
1488int lttng_metadata_ring_buffer_open(struct inode *inode, struct file *file)
1489{
1490 struct lttng_metadata_stream *stream = inode->i_private;
1491 struct lib_ring_buffer *buf = stream->priv;
1492
1493 file->private_data = buf;
b3b8072b
MD		 1494 /*
1495 * Since life-time of metadata cache differs from that of
1496 * session, we need to keep our own reference on the transport.
1497 */
1498 if (!try_module_get(stream->transport->owner)) {
5a15f70c 1499 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
b3b8072b
MD		 1500 return -EBUSY;
1501 }
d83004aa
JD		 1502 return lib_ring_buffer_open(inode, file, buf);
1503}
1504
1505static
1506int lttng_metadata_ring_buffer_release(struct inode *inode, struct file *file)
1507{
1508 struct lttng_metadata_stream *stream = file->private_data;
1509 struct lib_ring_buffer *buf = stream->priv;
1510
92143b2c
MD		 1511 mutex_lock(&stream->metadata_cache->lock);
1512 list_del(&stream->list);
1513 mutex_unlock(&stream->metadata_cache->lock);
d83004aa 1514 kref_put(&stream->metadata_cache->refcount, metadata_cache_destroy);
b3b8072b 1515 module_put(stream->transport->owner);
92143b2c 1516 kfree(stream);
d83004aa
JD		 1517 return lib_ring_buffer_release(inode, file, buf);
1518}
1519
1520static
1521ssize_t lttng_metadata_ring_buffer_splice_read(struct file *in, loff_t *ppos,
1522 struct pipe_inode_info *pipe, size_t len,
1523 unsigned int flags)
1524{
1525 struct lttng_metadata_stream *stream = in->private_data;
1526 struct lib_ring_buffer *buf = stream->priv;
1527
1528 return lib_ring_buffer_splice_read(in, ppos, pipe, len,
1529 flags, buf);
1530}
1531
1532static
1533int lttng_metadata_ring_buffer_mmap(struct file *filp,
1534 struct vm_area_struct *vma)
1535{
1536 struct lttng_metadata_stream *stream = filp->private_data;
1537 struct lib_ring_buffer *buf = stream->priv;
1538
1539 return lib_ring_buffer_mmap(filp, vma, buf);
1540}
1541
1542static
1543const struct file_operations lttng_metadata_ring_buffer_file_operations = {
1544 .owner = THIS_MODULE,
1545 .open = lttng_metadata_ring_buffer_open,
1546 .release = lttng_metadata_ring_buffer_release,
1547 .poll = lttng_metadata_ring_buffer_poll,
1548 .splice_read = lttng_metadata_ring_buffer_splice_read,
1549 .mmap = lttng_metadata_ring_buffer_mmap,
1550 .unlocked_ioctl = lttng_metadata_ring_buffer_ioctl,
1551 .llseek = vfs_lib_ring_buffer_no_llseek,
1552#ifdef CONFIG_COMPAT
1553 .compat_ioctl = lttng_metadata_ring_buffer_compat_ioctl,
1554#endif
1555};
1556
1557static
1558int lttng_abi_create_stream_fd(struct file *channel_file, void *stream_priv,
a3fcd499 1559 const struct file_operations *fops, const char *name)
ad1c05e1 1560{
ad1c05e1 1561 int stream_fd, ret;
11b5a3c2 1562 struct file *stream_file;
ad1c05e1 1563
4ac10b76 1564 stream_fd = lttng_get_unused_fd();
ad1c05e1
MD		 1565 if (stream_fd < 0) {
1566 ret = stream_fd;
1567 goto fd_error;
1568 }
a3fcd499 1569 stream_file = anon_inode_getfile(name, fops, stream_priv, O_RDWR);
c0e31d2e
MD		 1570 if (IS_ERR(stream_file)) {
1571 ret = PTR_ERR(stream_file);
ad1c05e1
MD		 1572 goto file_error;
1573 }
409453cb
MD		 1574 /*
1575 * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
1576 * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
1577 * file descriptor, so we set FMODE_PREAD here.
1578 */
d7b6f197 1579 stream_file->f_mode |= FMODE_PREAD;
c0e31d2e 1580 fd_install(stream_fd, stream_file);
dda6a249
MD		 1581 /*
1582 * The stream holds a reference to the channel within the generic ring
1583 * buffer library, so no need to hold a refcount on the channel and
1584 * session files here.
1585 */
ad1c05e1
MD		 1586 return stream_fd;
1587
1588file_error:
1589 put_unused_fd(stream_fd);
d83004aa
JD		 1590fd_error:
1591 return ret;
1592}
1593
1594static
1595int lttng_abi_open_stream(struct file *channel_file)
1596{
1597 struct lttng_channel *channel = channel_file->private_data;
1598 struct lib_ring_buffer *buf;
1599 int ret;
1600 void *stream_priv;
1601
1602 buf = channel->ops->buffer_read_open(channel->chan);
1603 if (!buf)
1604 return -ENOENT;
1605
1606 stream_priv = buf;
1607 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
a3fcd499
MD		 1608 &lttng_stream_ring_buffer_file_operations,
1609 "[lttng_stream]");
d83004aa
JD		 1610 if (ret < 0)
1611 goto fd_error;
1612
1613 return ret;
1614
1615fd_error:
1616 channel->ops->buffer_read_close(buf);
1617 return ret;
1618}
1619
1620static
1621int lttng_abi_open_metadata_stream(struct file *channel_file)
1622{
1623 struct lttng_channel *channel = channel_file->private_data;
1624 struct lttng_session *session = channel->session;
1625 struct lib_ring_buffer *buf;
1626 int ret;
1627 struct lttng_metadata_stream *metadata_stream;
1628 void *stream_priv;
1629
1630 buf = channel->ops->buffer_read_open(channel->chan);
1631 if (!buf)
1632 return -ENOENT;
1633
1634 metadata_stream = kzalloc(sizeof(struct lttng_metadata_stream),
1635 GFP_KERNEL);
b3b8072b
MD		 1636 if (!metadata_stream) {
1637 ret = -ENOMEM;
1638 goto nomem;
1639 }
d83004aa
JD		 1640 metadata_stream->metadata_cache = session->metadata_cache;
1641 init_waitqueue_head(&metadata_stream->read_wait);
1642 metadata_stream->priv = buf;
1643 stream_priv = metadata_stream;
b3b8072b 1644 metadata_stream->transport = channel->transport;
8b97fd42
MD		 1645 /* Initial state is an empty metadata, considered as incoherent. */
1646 metadata_stream->coherent = false;
b3b8072b
MD		 1647
1648 /*
1649 * Since life-time of metadata cache differs from that of
1650 * session, we need to keep our own reference on the transport.
1651 */
1652 if (!try_module_get(metadata_stream->transport->owner)) {
5a15f70c 1653 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
b3b8072b
MD		 1654 ret = -EINVAL;
1655 goto notransport;
1656 }
1657
901aaa5f
FD		 1658 if (!lttng_kref_get(&session->metadata_cache->refcount)) {
1659 ret = -EOVERFLOW;
9c1f4643 1660 goto kref_error;
901aaa5f
FD		 1661 }
1662
d83004aa 1663 ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
a3fcd499
MD		 1664 &lttng_metadata_ring_buffer_file_operations,
1665 "[lttng_metadata_stream]");
d83004aa
JD		 1666 if (ret < 0)
1667 goto fd_error;
1668
92143b2c 1669 mutex_lock(&session->metadata_cache->lock);
d83004aa
JD		 1670 list_add(&metadata_stream->list,
1671 &session->metadata_cache->metadata_stream);
92143b2c 1672 mutex_unlock(&session->metadata_cache->lock);
d83004aa
JD		 1673 return ret;
1674
ad1c05e1 1675fd_error:
9c1f4643
MD		 1676 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
1677kref_error:
b3b8072b
MD		 1678 module_put(metadata_stream->transport->owner);
1679notransport:
1680 kfree(metadata_stream);
1681nomem:
11b5a3c2 1682 channel->ops->buffer_read_close(buf);
ad1c05e1
MD		 1683 return ret;
1684}
1685
21f58fb7
FD		 1686static
1687int lttng_abi_open_event_notifier_group_stream(struct file *notif_file)
1688{
1689 struct lttng_event_notifier_group *event_notifier_group = notif_file->private_data;
1690 struct channel *chan = event_notifier_group->chan;
1691 struct lib_ring_buffer *buf;
1692 int ret;
1693 void *stream_priv;
1694
1695 buf = event_notifier_group->ops->buffer_read_open(chan);
1696 if (!buf)
1697 return -ENOENT;
1698
1699 /* The event_notifier notification fd holds a reference on the event_notifier group */
1700 if (!atomic_long_add_unless(&notif_file->f_count, 1, LONG_MAX)) {
1701 ret = -EOVERFLOW;
1702 goto refcount_error;
1703 }
1704 event_notifier_group->buf = buf;
1705 stream_priv = event_notifier_group;
1706 ret = lttng_abi_create_stream_fd(notif_file, stream_priv,
1707 &lttng_event_notifier_group_notif_fops,
1708 "[lttng_event_notifier_stream]");
1709 if (ret < 0)
1710 goto fd_error;
1711
1712 return ret;
1713
1714fd_error:
1715 atomic_long_dec(&notif_file->f_count);
1716refcount_error:
1717 event_notifier_group->ops->buffer_read_close(buf);
1718 return ret;
1719}
1720
badfe9f5
MD		 1721static
1722int lttng_abi_validate_event_param(struct lttng_kernel_event *event_param)
1723{
1724 /* Limit ABI to implemented features. */
1725 switch (event_param->instrumentation) {
1726 case LTTNG_KERNEL_SYSCALL:
1727 switch (event_param->u.syscall.entryexit) {
c5d12b5b
FD		 1728 case LTTNG_KERNEL_SYSCALL_ENTRY:
1729 case LTTNG_KERNEL_SYSCALL_EXIT:
badfe9f5
MD		 1730 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
1731 break;
1732 default:
1733 return -EINVAL;
1734 }
1735 switch (event_param->u.syscall.abi) {
1736 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
1737 break;
1738 default:
1739 return -EINVAL;
1740 }
1741 switch (event_param->u.syscall.match) {
cff6938b 1742 case LTTNG_KERNEL_SYSCALL_MATCH_NAME:
badfe9f5
MD		 1743 break;
1744 default:
1745 return -EINVAL;
1746 }
1747 break;
1748
1749 case LTTNG_KERNEL_TRACEPOINT: /* Fallthrough */
1750 case LTTNG_KERNEL_KPROBE: /* Fallthrough */
1751 case LTTNG_KERNEL_KRETPROBE: /* Fallthrough */
1752 case LTTNG_KERNEL_NOOP: /* Fallthrough */
1753 case LTTNG_KERNEL_UPROBE:
1754 break;
1755
1756 case LTTNG_KERNEL_FUNCTION: /* Fallthrough */
1757 default:
1758 return -EINVAL;
1759 }
1760 return 0;
1761}
1762
653fe716 1763static
c0e31d2e 1764int lttng_abi_create_event(struct file *channel_file,
6dccd6c1 1765 struct lttng_kernel_event *event_param)
653fe716 1766{
a90917c3 1767 struct lttng_channel *channel = channel_file->private_data;
653fe716 1768 int event_fd, ret;
11b5a3c2 1769 struct file *event_file;
3c997079 1770 void *priv;
653fe716 1771
6dccd6c1
JD		 1772 event_param->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1773 switch (event_param->instrumentation) {
7371f44c 1774 case LTTNG_KERNEL_KRETPROBE:
6dccd6c1 1775 event_param->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
7371f44c 1776 break;
ab2277d6 1777 case LTTNG_KERNEL_KPROBE:
6dccd6c1 1778 event_param->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
e0a7a7c4 1779 break;
ab2277d6 1780 case LTTNG_KERNEL_FUNCTION:
e884017c
MD		 1781 WARN_ON_ONCE(1);
1782 /* Not implemented. */
e0a7a7c4
MD		 1783 break;
1784 default:
1785 break;
1786 }
33a39a3c
MD		 1787 event_fd = lttng_get_unused_fd();
1788 if (event_fd < 0) {
1789 ret = event_fd;
1790 goto fd_error;
1791 }
1792 event_file = anon_inode_getfile("[lttng_event]",
1793 &lttng_event_fops,
1794 NULL, O_RDWR);
1795 if (IS_ERR(event_file)) {
1796 ret = PTR_ERR(event_file);
1797 goto file_error;
1798 }
9c1f4643 1799 /* The event holds a reference on the channel */
98d7281c 1800 if (!atomic_long_add_unless(&channel_file->f_count, 1, LONG_MAX)) {
0d2c717f 1801 ret = -EOVERFLOW;
9c1f4643
MD		 1802 goto refcount_error;
1803 }
badfe9f5
MD		 1804 ret = lttng_abi_validate_event_param(event_param);
1805 if (ret)
1806 goto event_error;
33a39a3c
MD		 1807 if (event_param->instrumentation == LTTNG_KERNEL_TRACEPOINT
1808 || event_param->instrumentation == LTTNG_KERNEL_SYSCALL) {
b2bc0bc8 1809 struct lttng_event_enabler *event_enabler;
33a39a3c 1810
4993071a
PP		 1811 if (strutils_is_star_glob_pattern(event_param->name)) {
1812 /*
1813 * If the event name is a star globbing pattern,
1814 * we create the special star globbing enabler.
1815 */
b2bc0bc8 1816 event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_STAR_GLOB,
33a39a3c 1817 event_param, channel);
3c997079 1818 } else {
b2bc0bc8 1819 event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_NAME,
33a39a3c 1820 event_param, channel);
1ec65de1 1821 }
b2bc0bc8 1822 priv = event_enabler;
33a39a3c
MD		 1823 } else {
1824 struct lttng_event *event;
4ee2453d 1825
33a39a3c
MD		 1826 /*
1827 * We tolerate no failure path after event creation. It
1828 * will stay invariant for the rest of the session.
1829 */
1830 event = lttng_event_create(channel, event_param,
1831 NULL, NULL,
1832 event_param->instrumentation);
1833 WARN_ON_ONCE(!event);
1834 if (IS_ERR(event)) {
1835 ret = PTR_ERR(event);
1836 goto event_error;
80f87dd2 1837 }
33a39a3c 1838 priv = event;
03037b98 1839 }
33a39a3c
MD		 1840 event_file->private_data = priv;
1841 fd_install(event_fd, event_file);
653fe716
MD		 1842 return event_fd;
1843
03037b98 1844event_error:
9c1f4643
MD		 1845 atomic_long_dec(&channel_file->f_count);
1846refcount_error:
c0e31d2e 1847 fput(event_file);
653fe716
MD		 1848file_error:
1849 put_unused_fd(event_fd);
1850fd_error:
653fe716
MD		 1851 return ret;
1852}
ad1c05e1 1853
dffef45d
FD		 1854static
1855long lttng_event_notifier_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1856{
2b16f0c9 1857 struct lttng_event_notifier *event_notifier;
dffef45d
FD		 1858 struct lttng_event_notifier_enabler *event_notifier_enabler;
1859 enum lttng_event_type *evtype = file->private_data;
1860
1861 switch (cmd) {
1862 case LTTNG_KERNEL_ENABLE:
1863 switch (*evtype) {
1864 case LTTNG_TYPE_EVENT:
2b16f0c9
FD		 1865 event_notifier = file->private_data;
1866 return lttng_event_notifier_enable(event_notifier);
dffef45d
FD		 1867 case LTTNG_TYPE_ENABLER:
1868 event_notifier_enabler = file->private_data;
1869 return lttng_event_notifier_enabler_enable(event_notifier_enabler);
1870 default:
1871 WARN_ON_ONCE(1);
1872 return -ENOSYS;
1873 }
1874 case LTTNG_KERNEL_DISABLE:
1875 switch (*evtype) {
1876 case LTTNG_TYPE_EVENT:
2b16f0c9
FD		 1877 event_notifier = file->private_data;
1878 return lttng_event_notifier_disable(event_notifier);
dffef45d
FD		 1879 case LTTNG_TYPE_ENABLER:
1880 event_notifier_enabler = file->private_data;
1881 return lttng_event_notifier_enabler_disable(event_notifier_enabler);
1882 default:
1883 WARN_ON_ONCE(1);
1884 return -ENOSYS;
1885 }
1886 case LTTNG_KERNEL_FILTER:
1887 switch (*evtype) {
1888 case LTTNG_TYPE_EVENT:
1889 return -EINVAL;
1890 case LTTNG_TYPE_ENABLER:
1891 event_notifier_enabler = file->private_data;
183e8b3a
FD		 1892 return lttng_event_notifier_enabler_attach_filter_bytecode(
1893 event_notifier_enabler,
dffef45d
FD		 1894 (struct lttng_kernel_filter_bytecode __user *) arg);
1895 default:
1896 WARN_ON_ONCE(1);
1897 return -ENOSYS;
1898 }
99d223ad
FD		 1899
1900 case LTTNG_KERNEL_CAPTURE:
1901 switch (*evtype) {
1902 case LTTNG_TYPE_EVENT:
1903 return -EINVAL;
1904 case LTTNG_TYPE_ENABLER:
1905 event_notifier_enabler = file->private_data;
1906 return lttng_event_notifier_enabler_attach_capture_bytecode(
1907 event_notifier_enabler,
1908 (struct lttng_kernel_capture_bytecode __user *) arg);
1909 default:
1910 WARN_ON_ONCE(1);
1911 return -ENOSYS;
1912 }
9de67196
FD		 1913 case LTTNG_KERNEL_ADD_CALLSITE:
1914 switch (*evtype) {
1915 case LTTNG_TYPE_EVENT:
1916 event_notifier = file->private_data;
1917 return lttng_event_notifier_add_callsite(event_notifier,
1918 (struct lttng_kernel_event_callsite __user *) arg);
1919 case LTTNG_TYPE_ENABLER:
1920 return -EINVAL;
1921 default:
1922 WARN_ON_ONCE(1);
1923 return -ENOSYS;
1924 }
dffef45d
FD		 1925 default:
1926 return -ENOIOCTLCMD;
1927 }
1928}
1929
1930static
1931int lttng_event_notifier_release(struct inode *inode, struct file *file)
1932{
1933 struct lttng_event_notifier *event_notifier;
1934 struct lttng_event_notifier_enabler *event_notifier_enabler;
1935 enum lttng_event_type *evtype = file->private_data;
1936
1937 if (!evtype)
1938 return 0;
1939
1940 switch (*evtype) {
1941 case LTTNG_TYPE_EVENT:
1942 event_notifier = file->private_data;
1943 if (event_notifier)
1944 fput(event_notifier->group->file);
1945 break;
1946 case LTTNG_TYPE_ENABLER:
1947 event_notifier_enabler = file->private_data;
1948 if (event_notifier_enabler)
1949 fput(event_notifier_enabler->group->file);
1950 break;
1951 default:
1952 WARN_ON_ONCE(1);
1953 break;
1954 }
1955
1956 return 0;
1957}
1958
1959static const struct file_operations lttng_event_notifier_fops = {
1960 .owner = THIS_MODULE,
1961 .release = lttng_event_notifier_release,
1962 .unlocked_ioctl = lttng_event_notifier_ioctl,
1963#ifdef CONFIG_COMPAT
1964 .compat_ioctl = lttng_event_notifier_ioctl,
1965#endif
1966};
1967
1968static
1969int lttng_abi_create_event_notifier(struct file *event_notifier_group_file,
1970 struct lttng_kernel_event_notifier *event_notifier_param)
1971{
1972 struct lttng_event_notifier_group *event_notifier_group =
1973 event_notifier_group_file->private_data;
1974 int event_notifier_fd, ret;
1975 struct file *event_notifier_file;
1976 void *priv;
1977
1978 switch (event_notifier_param->event.instrumentation) {
1979 case LTTNG_KERNEL_TRACEPOINT:
9de67196 1980 case LTTNG_KERNEL_UPROBE:
b01155ba 1981 break;
dffef45d 1982 case LTTNG_KERNEL_KPROBE:
2b16f0c9
FD		 1983 event_notifier_param->event.u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1984 break;
8a8ac9a8
FD		 1985 case LTTNG_KERNEL_SYSCALL:
1986 break;
dffef45d 1987 case LTTNG_KERNEL_KRETPROBE:
9de67196 1988 /* Placing an event notifier on kretprobe is not supported. */
dffef45d
FD		 1989 case LTTNG_KERNEL_FUNCTION:
1990 case LTTNG_KERNEL_NOOP:
dffef45d
FD		 1991 default:
1992 ret = -EINVAL;
1993 goto inval_instr;
1994 }
1995
1996 event_notifier_param->event.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
1997
1998 event_notifier_fd = lttng_get_unused_fd();
1999 if (event_notifier_fd < 0) {
2000 ret = event_notifier_fd;
2001 goto fd_error;
2002 }
2003
2004 event_notifier_file = anon_inode_getfile("[lttng_event_notifier]",
2005 &lttng_event_notifier_fops,
2006 NULL, O_RDWR);
2007 if (IS_ERR(event_notifier_file)) {
2008 ret = PTR_ERR(event_notifier_file);
2009 goto file_error;
2010 }
2011
2012 /* The event notifier holds a reference on the event notifier group. */
2013 if (!atomic_long_add_unless(&event_notifier_group_file->f_count, 1, LONG_MAX)) {
2014 ret = -EOVERFLOW;
2015 goto refcount_error;
2016 }
2017
2018 if (event_notifier_param->event.instrumentation == LTTNG_KERNEL_TRACEPOINT
2019 || event_notifier_param->event.instrumentation == LTTNG_KERNEL_SYSCALL) {
2020 struct lttng_event_notifier_enabler *enabler;
2021
2022 if (strutils_is_star_glob_pattern(event_notifier_param->event.name)) {
2023 /*
2024 * If the event name is a star globbing pattern,
2025 * we create the special star globbing enabler.
2026 */
2027 enabler = lttng_event_notifier_enabler_create(
2028 event_notifier_group,
2029 LTTNG_ENABLER_FORMAT_STAR_GLOB,
2030 event_notifier_param);
2031 } else {
2032 enabler = lttng_event_notifier_enabler_create(
2033 event_notifier_group,
2034 LTTNG_ENABLER_FORMAT_NAME,
2035 event_notifier_param);
2036 }
2037 priv = enabler;
2038 } else {
2039 struct lttng_event_notifier *event_notifier;
2040
2041 /*
2042 * We tolerate no failure path after event notifier creation.
2043 * It will stay invariant for the rest of the session.
2044 */
2045 event_notifier = lttng_event_notifier_create(NULL,
99f52fcc
FD		 2046 event_notifier_param->event.token,
2047 event_notifier_param->error_counter_index,
2048 event_notifier_group,
dffef45d
FD		 2049 event_notifier_param, NULL,
2050 event_notifier_param->event.instrumentation);
2051 WARN_ON_ONCE(!event_notifier);
2052 if (IS_ERR(event_notifier)) {
2053 ret = PTR_ERR(event_notifier);
2054 goto event_notifier_error;
2055 }
2056 priv = event_notifier;
2057 }
2058 event_notifier_file->private_data = priv;
2059 fd_install(event_notifier_fd, event_notifier_file);
2060 return event_notifier_fd;
2061
2062event_notifier_error:
2063 atomic_long_dec(&event_notifier_group_file->f_count);
2064refcount_error:
2065 fput(event_notifier_file);
2066file_error:
2067 put_unused_fd(event_notifier_fd);
2068fd_error:
2069inval_instr:
2070 return ret;
2071}
2072
99f52fcc
FD		 2073static
2074long lttng_abi_event_notifier_group_create_error_counter(
2075 struct file *event_notifier_group_file,
2076 const struct lttng_kernel_counter_conf *error_counter_conf)
2077{
2078 int counter_fd, ret;
2079 char *counter_transport_name;
2080 size_t counter_len;
2081 struct lttng_counter *counter = NULL;
2082 struct file *counter_file;
2083 struct lttng_event_notifier_group *event_notifier_group =
2084 (struct lttng_event_notifier_group *) event_notifier_group_file->private_data;
2085
2086 if (error_counter_conf->arithmetic != LTTNG_KERNEL_COUNTER_ARITHMETIC_MODULAR) {
2087 printk(KERN_ERR "LTTng: event_notifier: Error counter of the wrong arithmetic type.\n");
2088 return -EINVAL;
2089 }
2090
2091 if (error_counter_conf->number_dimensions != 1) {
2092 printk(KERN_ERR "LTTng: event_notifier: Error counter has more than one dimension.\n");
2093 return -EINVAL;
2094 }
2095
2096 switch (error_counter_conf->bitness) {
2097 case LTTNG_KERNEL_COUNTER_BITNESS_64:
2098 counter_transport_name = "counter-per-cpu-64-modular";
2099 break;
2100 case LTTNG_KERNEL_COUNTER_BITNESS_32:
2101 counter_transport_name = "counter-per-cpu-32-modular";
2102 break;
2103 default:
2104 return -EINVAL;
2105 }
2106
2107 /*
2108 * Lock sessions to provide mutual exclusion against concurrent
2109 * modification of event_notifier group, which would result in
2110 * overwriting the error counter if set concurrently.
2111 */
2112 lttng_lock_sessions();
2113
2114 if (event_notifier_group->error_counter) {
2115 printk(KERN_ERR "Error counter already created in event_notifier group\n");
2116 ret = -EBUSY;
2117 goto fd_error;
2118 }
2119
2120 counter_fd = lttng_get_unused_fd();
2121 if (counter_fd < 0) {
2122 ret = counter_fd;
2123 goto fd_error;
2124 }
2125
2126 counter_file = anon_inode_getfile("[lttng_counter]",
2127 &lttng_counter_fops,
2128 NULL, O_RDONLY);
2129 if (IS_ERR(counter_file)) {
2130 ret = PTR_ERR(counter_file);
2131 goto file_error;
2132 }
2133
2134 counter_len = error_counter_conf->dimensions[0].size;
2135
2136 if (!atomic_long_add_unless(&event_notifier_group_file->f_count, 1, LONG_MAX)) {
2137 ret = -EOVERFLOW;
2138 goto refcount_error;
2139 }
2140
2141 counter = lttng_kernel_counter_create(counter_transport_name,
2142 1, &counter_len);
2143 if (!counter) {
2144 ret = -EINVAL;
2145 goto counter_error;
2146 }
2147
99f52fcc 2148 event_notifier_group->error_counter_len = counter_len;
ab04d7b1
MD		 2149 /*
2150 * store-release to publish error counter matches load-acquire
2151 * in record_error. Ensures the counter is created and the
2152 * error_counter_len is set before they are used.
2153 */
6657edec 2154 lttng_smp_store_release(&event_notifier_group->error_counter, counter);
99f52fcc
FD		 2155
2156 counter->file = counter_file;
2157 counter->owner = event_notifier_group->file;
2158 counter_file->private_data = counter;
2159 /* Ownership transferred. */
2160 counter = NULL;
2161
2162 fd_install(counter_fd, counter_file);
2163 lttng_unlock_sessions();
2164
2165 return counter_fd;
2166
2167counter_error:
2168 atomic_long_dec(&event_notifier_group_file->f_count);
2169refcount_error:
2170 fput(counter_file);
2171file_error:
2172 put_unused_fd(counter_fd);
2173fd_error:
2174 lttng_unlock_sessions();
2175 return ret;
2176}
2177
750b05f2
FD		 2178static
2179long lttng_event_notifier_group_ioctl(struct file *file, unsigned int cmd,
2180 unsigned long arg)
2181{
2182 switch (cmd) {
21f58fb7
FD		 2183 case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD:
2184 {
2185 return lttng_abi_open_event_notifier_group_stream(file);
2186 }
dffef45d
FD		 2187 case LTTNG_KERNEL_EVENT_NOTIFIER_CREATE:
2188 {
2189 struct lttng_kernel_event_notifier uevent_notifier_param;
2190
2191 if (copy_from_user(&uevent_notifier_param,
2192 (struct lttng_kernel_event_notifier __user *) arg,
2193 sizeof(uevent_notifier_param)))
2194 return -EFAULT;
2195 return lttng_abi_create_event_notifier(file, &uevent_notifier_param);
2196 }
99f52fcc
FD		 2197 case LTTNG_KERNEL_COUNTER:
2198 {
2199 struct lttng_kernel_counter_conf uerror_counter_conf;
2200
2201 if (copy_from_user(&uerror_counter_conf,
2202 (struct lttng_kernel_counter_conf __user *) arg,
2203 sizeof(uerror_counter_conf)))
2204 return -EFAULT;
2205 return lttng_abi_event_notifier_group_create_error_counter(file,
2206 &uerror_counter_conf);
2207 }
750b05f2
FD		 2208 default:
2209 return -ENOIOCTLCMD;
2210 }
2211 return 0;
2212}
2213
2214static
2215int lttng_event_notifier_group_release(struct inode *inode, struct file *file)
2216{
2217 struct lttng_event_notifier_group *event_notifier_group =
2218 file->private_data;
2219
2220 if (event_notifier_group)
2221 lttng_event_notifier_group_destroy(event_notifier_group);
2222 return 0;
2223}
2224
2225static const struct file_operations lttng_event_notifier_group_fops = {
2226 .owner = THIS_MODULE,
2227 .release = lttng_event_notifier_group_release,
2228 .unlocked_ioctl = lttng_event_notifier_group_ioctl,
2229#ifdef CONFIG_COMPAT
2230 .compat_ioctl = lttng_event_notifier_group_ioctl,
2231#endif
2232};
2233
ad1c05e1
MD		 2234/**
2235 * lttng_channel_ioctl - lttng syscall through ioctl
2236 *
c0e31d2e 2237 * @file: the file
ad1c05e1
MD		 2238 * @cmd: the command
2239 * @arg: command arg
2240 *
2241 * This ioctl implements lttng commands:
38d024ae 2242 * LTTNG_KERNEL_STREAM
ad1c05e1
MD		 2243 * Returns an event stream file descriptor or failure.
2244 * (typically, one event stream records events from one CPU)
38d024ae 2245 * LTTNG_KERNEL_EVENT
ad1c05e1 2246 * Returns an event file descriptor or failure.
8070f5c0
MD		 2247 * LTTNG_KERNEL_CONTEXT
2248 * Prepend a context field to each event in the channel
e64957da
MD		 2249 * LTTNG_KERNEL_ENABLE
2250 * Enable recording for events in this channel (weak enable)
2251 * LTTNG_KERNEL_DISABLE
2252 * Disable recording for events in this channel (strong disable)
baf20995 2253 *
baf20995
MD		 2254 * Channel and event file descriptors also hold a reference on the session.
2255 */
ad1c05e1 2256static
c0e31d2e 2257long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
baf20995 2258{
a90917c3 2259 struct lttng_channel *channel = file->private_data;
8070f5c0 2260
baf20995 2261 switch (cmd) {
6dccd6c1 2262 case LTTNG_KERNEL_OLD_STREAM:
38d024ae 2263 case LTTNG_KERNEL_STREAM:
c0e31d2e 2264 return lttng_abi_open_stream(file);
6dccd6c1
JD		 2265 case LTTNG_KERNEL_OLD_EVENT:
2266 {
2267 struct lttng_kernel_event *uevent_param;
2268 struct lttng_kernel_old_event *old_uevent_param;
2269 int ret;
2270
2271 uevent_param = kmalloc(sizeof(struct lttng_kernel_event),
2272 GFP_KERNEL);
2273 if (!uevent_param) {
2274 ret = -ENOMEM;
2275 goto old_event_end;
2276 }
2277 old_uevent_param = kmalloc(
2278 sizeof(struct lttng_kernel_old_event),
2279 GFP_KERNEL);
2280 if (!old_uevent_param) {
2281 ret = -ENOMEM;
2282 goto old_event_error_free_param;
2283 }
2284 if (copy_from_user(old_uevent_param,
2285 (struct lttng_kernel_old_event __user *) arg,
2286 sizeof(struct lttng_kernel_old_event))) {
2287 ret = -EFAULT;
2288 goto old_event_error_free_old_param;
2289 }
2290
2291 memcpy(uevent_param->name, old_uevent_param->name,
2292 sizeof(uevent_param->name));
2293 uevent_param->instrumentation =
2294 old_uevent_param->instrumentation;
2295
2296 switch (old_uevent_param->instrumentation) {
2297 case LTTNG_KERNEL_KPROBE:
2298 uevent_param->u.kprobe.addr =
2299 old_uevent_param->u.kprobe.addr;
2300 uevent_param->u.kprobe.offset =
2301 old_uevent_param->u.kprobe.offset;
2302 memcpy(uevent_param->u.kprobe.symbol_name,
2303 old_uevent_param->u.kprobe.symbol_name,
2304 sizeof(uevent_param->u.kprobe.symbol_name));
2305 break;
2306 case LTTNG_KERNEL_KRETPROBE:
2307 uevent_param->u.kretprobe.addr =
2308 old_uevent_param->u.kretprobe.addr;
2309 uevent_param->u.kretprobe.offset =
2310 old_uevent_param->u.kretprobe.offset;
2311 memcpy(uevent_param->u.kretprobe.symbol_name,
2312 old_uevent_param->u.kretprobe.symbol_name,
2313 sizeof(uevent_param->u.kretprobe.symbol_name));
2314 break;
2315 case LTTNG_KERNEL_FUNCTION:
e884017c
MD		 2316 WARN_ON_ONCE(1);
2317 /* Not implemented. */
6dccd6c1
JD		 2318 break;
2319 default:
2320 break;
2321 }
2322 ret = lttng_abi_create_event(file, uevent_param);
2323
2324old_event_error_free_old_param:
2325 kfree(old_uevent_param);
2326old_event_error_free_param:
2327 kfree(uevent_param);
2328old_event_end:
2329 return ret;
2330 }
38d024ae 2331 case LTTNG_KERNEL_EVENT:
6dccd6c1
JD		 2332 {
2333 struct lttng_kernel_event uevent_param;
2334
2335 if (copy_from_user(&uevent_param,
2336 (struct lttng_kernel_event __user *) arg,
2337 sizeof(uevent_param)))
2338 return -EFAULT;
2339 return lttng_abi_create_event(file, &uevent_param);
2340 }
2341 case LTTNG_KERNEL_OLD_CONTEXT:
2342 {
2343 struct lttng_kernel_context *ucontext_param;
2344 struct lttng_kernel_old_context *old_ucontext_param;
2345 int ret;
2346
2347 ucontext_param = kmalloc(sizeof(struct lttng_kernel_context),
2348 GFP_KERNEL);
2349 if (!ucontext_param) {
2350 ret = -ENOMEM;
2351 goto old_ctx_end;
2352 }
2353 old_ucontext_param = kmalloc(sizeof(struct lttng_kernel_old_context),
2354 GFP_KERNEL);
2355 if (!old_ucontext_param) {
2356 ret = -ENOMEM;
2357 goto old_ctx_error_free_param;
2358 }
2359
2360 if (copy_from_user(old_ucontext_param,
2361 (struct lttng_kernel_old_context __user *) arg,
2362 sizeof(struct lttng_kernel_old_context))) {
2363 ret = -EFAULT;
2364 goto old_ctx_error_free_old_param;
2365 }
2366 ucontext_param->ctx = old_ucontext_param->ctx;
2367 memcpy(ucontext_param->padding, old_ucontext_param->padding,
2368 sizeof(ucontext_param->padding));
2369 /* only type that uses the union */
2370 if (old_ucontext_param->ctx == LTTNG_KERNEL_CONTEXT_PERF_COUNTER) {
2371 ucontext_param->u.perf_counter.type =
2372 old_ucontext_param->u.perf_counter.type;
2373 ucontext_param->u.perf_counter.config =
2374 old_ucontext_param->u.perf_counter.config;
2375 memcpy(ucontext_param->u.perf_counter.name,
2376 old_ucontext_param->u.perf_counter.name,
2377 sizeof(ucontext_param->u.perf_counter.name));
2378 }
2379
2380 ret = lttng_abi_add_context(file,
2381 ucontext_param,
2382 &channel->ctx, channel->session);
2383
2384old_ctx_error_free_old_param:
2385 kfree(old_ucontext_param);
2386old_ctx_error_free_param:
2387 kfree(ucontext_param);
2388old_ctx_end:
2389 return ret;
2390 }
8070f5c0 2391 case LTTNG_KERNEL_CONTEXT:
6dccd6c1
JD		 2392 {
2393 struct lttng_kernel_context ucontext_param;
2394
2395 if (copy_from_user(&ucontext_param,
8070f5c0 2396 (struct lttng_kernel_context __user *) arg,
6dccd6c1
JD		 2397 sizeof(ucontext_param)))
2398 return -EFAULT;
2399 return lttng_abi_add_context(file,
2400 &ucontext_param,
8070f5c0 2401 &channel->ctx, channel->session);
6dccd6c1
JD		 2402 }
2403 case LTTNG_KERNEL_OLD_ENABLE:
e64957da 2404 case LTTNG_KERNEL_ENABLE:
a90917c3 2405 return lttng_channel_enable(channel);
6dccd6c1 2406 case LTTNG_KERNEL_OLD_DISABLE:
e64957da 2407 case LTTNG_KERNEL_DISABLE:
a90917c3 2408 return lttng_channel_disable(channel);
12e579db
MD		 2409 case LTTNG_KERNEL_SYSCALL_MASK:
2410 return lttng_channel_syscall_mask(channel,
2411 (struct lttng_kernel_syscall_mask __user *) arg);
baf20995
MD		 2412 default:
2413 return -ENOIOCTLCMD;
2414 }
2415}
2416
5dbbdb43
MD		 2417/**
2418 * lttng_metadata_ioctl - lttng syscall through ioctl
2419 *
2420 * @file: the file
2421 * @cmd: the command
2422 * @arg: command arg
2423 *
2424 * This ioctl implements lttng commands:
38d024ae 2425 * LTTNG_KERNEL_STREAM
5dbbdb43
MD		 2426 * Returns an event stream file descriptor or failure.
2427 *
2428 * Channel and event file descriptors also hold a reference on the session.
2429 */
2430static
2431long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2432{
2433 switch (cmd) {
6dccd6c1 2434 case LTTNG_KERNEL_OLD_STREAM:
38d024ae 2435 case LTTNG_KERNEL_STREAM:
d83004aa 2436 return lttng_abi_open_metadata_stream(file);
5dbbdb43
MD		 2437 default:
2438 return -ENOIOCTLCMD;
2439 }
2440}
2441
653fe716
MD		 2442/**
2443 * lttng_channel_poll - lttng stream addition/removal monitoring
2444 *
c0e31d2e 2445 * @file: the file
653fe716
MD		 2446 * @wait: poll table
2447 */
c0e31d2e 2448unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
653fe716 2449{
a90917c3 2450 struct lttng_channel *channel = file->private_data;
653fe716
MD		 2451 unsigned int mask = 0;
2452
c0e31d2e 2453 if (file->f_mode & FMODE_READ) {
a33e44a6 2454 poll_wait_set_exclusive(wait);
24cedcfe
MD		 2455 poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
2456 wait);
653fe716 2457
254ec7bc
MD		 2458 if (channel->ops->is_disabled(channel->chan))
2459 return POLLERR;
24cedcfe 2460 if (channel->ops->is_finalized(channel->chan))
653fe716 2461 return POLLHUP;
f71ecafa 2462 if (channel->ops->buffer_has_read_closed_stream(channel->chan))
653fe716 2463 return POLLIN | POLLRDNORM;
f71ecafa 2464 return 0;
653fe716
MD		 2465 }
2466 return mask;
2467
2468}
2469
0a84a57f
MD		 2470static
2471int lttng_channel_release(struct inode *inode, struct file *file)
2472{
a90917c3 2473 struct lttng_channel *channel = file->private_data;
c269fff4
MD		 2474
2475 if (channel)
2476 fput(channel->session->file);
0a84a57f
MD		 2477 return 0;
2478}
2479
d83004aa
JD		 2480static
2481int lttng_metadata_channel_release(struct inode *inode, struct file *file)
2482{
2483 struct lttng_channel *channel = file->private_data;
2484
2485 if (channel) {
d83004aa 2486 fput(channel->session->file);
a3381417 2487 lttng_metadata_channel_destroy(channel);
d83004aa
JD		 2488 }
2489
2490 return 0;
2491}
2492
ad1c05e1 2493static const struct file_operations lttng_channel_fops = {
a33c9927 2494 .owner = THIS_MODULE,
03037b98 2495 .release = lttng_channel_release,
653fe716 2496 .poll = lttng_channel_poll,
ad1c05e1 2497 .unlocked_ioctl = lttng_channel_ioctl,
baf20995 2498#ifdef CONFIG_COMPAT
03037b98 2499 .compat_ioctl = lttng_channel_ioctl,
baf20995 2500#endif
11b5a3c2 2501};
baf20995 2502
5dbbdb43 2503static const struct file_operations lttng_metadata_fops = {
a33c9927 2504 .owner = THIS_MODULE,
d83004aa 2505 .release = lttng_metadata_channel_release,
5dbbdb43
MD		 2506 .unlocked_ioctl = lttng_metadata_ioctl,
2507#ifdef CONFIG_COMPAT
2508 .compat_ioctl = lttng_metadata_ioctl,
2509#endif
2510};
2511
8070f5c0
MD		 2512/**
2513 * lttng_event_ioctl - lttng syscall through ioctl
2514 *
2515 * @file: the file
2516 * @cmd: the command
2517 * @arg: command arg
2518 *
2519 * This ioctl implements lttng commands:
8070f5c0
MD		 2520 * LTTNG_KERNEL_CONTEXT
2521 * Prepend a context field to each record of this event
e64957da
MD		 2522 * LTTNG_KERNEL_ENABLE
2523 * Enable recording for this event (weak enable)
2524 * LTTNG_KERNEL_DISABLE
2525 * Disable recording for this event (strong disable)
8070f5c0
MD		 2526 */
2527static
2528long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2529{
3c997079 2530 struct lttng_event *event;
b2bc0bc8 2531 struct lttng_event_enabler *event_enabler;
3c997079 2532 enum lttng_event_type *evtype = file->private_data;
8070f5c0
MD		 2533
2534 switch (cmd) {
6dccd6c1
JD		 2535 case LTTNG_KERNEL_OLD_CONTEXT:
2536 {
3c997079
MD		 2537 /* Not implemented */
2538 return -ENOSYS;
6dccd6c1 2539 }
8070f5c0 2540 case LTTNG_KERNEL_CONTEXT:
6dccd6c1 2541 {
3c997079
MD		 2542 /* Not implemented */
2543 return -ENOSYS;
6dccd6c1
JD		 2544 }
2545 case LTTNG_KERNEL_OLD_ENABLE:
e64957da 2546 case LTTNG_KERNEL_ENABLE:
3c997079
MD		 2547 switch (*evtype) {
2548 case LTTNG_TYPE_EVENT:
2549 event = file->private_data;
2550 return lttng_event_enable(event);
2551 case LTTNG_TYPE_ENABLER:
b2bc0bc8
FD		 2552 event_enabler = file->private_data;
2553 return lttng_event_enabler_enable(event_enabler);
3c997079
MD		 2554 default:
2555 WARN_ON_ONCE(1);
2556 return -ENOSYS;
2557 }
6dccd6c1 2558 case LTTNG_KERNEL_OLD_DISABLE:
e64957da 2559 case LTTNG_KERNEL_DISABLE:
3c997079
MD		 2560 switch (*evtype) {
2561 case LTTNG_TYPE_EVENT:
2562 event = file->private_data;
2563 return lttng_event_disable(event);
2564 case LTTNG_TYPE_ENABLER:
b2bc0bc8
FD		 2565 event_enabler = file->private_data;
2566 return lttng_event_enabler_disable(event_enabler);
3c997079
MD		 2567 default:
2568 WARN_ON_ONCE(1);
2569 return -ENOSYS;
2570 }
07dfc1d0
MD		 2571 case LTTNG_KERNEL_FILTER:
2572 switch (*evtype) {
2573 case LTTNG_TYPE_EVENT:
2574 return -EINVAL;
2575 case LTTNG_TYPE_ENABLER:
2576 {
b2bc0bc8 2577 event_enabler = file->private_data;
183e8b3a
FD		 2578 return lttng_event_enabler_attach_filter_bytecode(
2579 event_enabler,
07dfc1d0
MD		 2580 (struct lttng_kernel_filter_bytecode __user *) arg);
2581 }
0586316f
MD		 2582 default:
2583 WARN_ON_ONCE(1);
2584 return -ENOSYS;
07dfc1d0 2585 }
3aed4dca
FD		 2586 case LTTNG_KERNEL_ADD_CALLSITE:
2587 switch (*evtype) {
2588 case LTTNG_TYPE_EVENT:
2589 event = file->private_data;
2590 return lttng_event_add_callsite(event,
2591 (struct lttng_kernel_event_callsite __user *) arg);
2592 case LTTNG_TYPE_ENABLER:
2593 return -EINVAL;
64c147c0
MD		 2594 default:
2595 WARN_ON_ONCE(1);
2596 return -ENOSYS;
3aed4dca 2597 }
8070f5c0
MD		 2598 default:
2599 return -ENOIOCTLCMD;
2600 }
2601}
2602
0a84a57f
MD		 2603static
2604int lttng_event_release(struct inode *inode, struct file *file)
2605{
3c997079 2606 struct lttng_event *event;
b2bc0bc8 2607 struct lttng_event_enabler *event_enabler;
3c997079
MD		 2608 enum lttng_event_type *evtype = file->private_data;
2609
2610 if (!evtype)
2611 return 0;
2612
2613 switch (*evtype) {
2614 case LTTNG_TYPE_EVENT:
2615 event = file->private_data;
2616 if (event)
2617 fput(event->chan->file);
2618 break;
2619 case LTTNG_TYPE_ENABLER:
b2bc0bc8
FD		 2620 event_enabler = file->private_data;
2621 if (event_enabler)
2622 fput(event_enabler->chan->file);
3c997079
MD		 2623 break;
2624 default:
2625 WARN_ON_ONCE(1);
2626 break;
2627 }
c269fff4 2628
0a84a57f
MD		 2629 return 0;
2630}
2631
3b923e5b 2632/* TODO: filter control ioctl */
0a84a57f 2633static const struct file_operations lttng_event_fops = {
a33c9927 2634 .owner = THIS_MODULE,
0a84a57f 2635 .release = lttng_event_release,
8070f5c0
MD		 2636 .unlocked_ioctl = lttng_event_ioctl,
2637#ifdef CONFIG_COMPAT
2638 .compat_ioctl = lttng_event_ioctl,
2639#endif
11b5a3c2 2640};
0a84a57f 2641
3b731ab1
JD		 2642static int put_u64(uint64_t val, unsigned long arg)
2643{
2644 return put_user(val, (uint64_t __user *) arg);
2645}
2646
8b97fd42
MD		 2647static int put_u32(uint32_t val, unsigned long arg)
2648{
2649 return put_user(val, (uint32_t __user *) arg);
2650}
2651
ed8d02d6
JD		 2652static long lttng_stream_ring_buffer_ioctl(struct file *filp,
2653 unsigned int cmd, unsigned long arg)
2654{
3b731ab1
JD		 2655 struct lib_ring_buffer *buf = filp->private_data;
2656 struct channel *chan = buf->backend.chan;
2657 const struct lib_ring_buffer_config *config = &chan->backend.config;
dd5a0db3 2658 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
3b731ab1
JD		 2659 int ret;
2660
2661 if (atomic_read(&chan->record_disabled))
2662 return -EIO;
2663
ed8d02d6 2664 switch (cmd) {
3b731ab1
JD		 2665 case LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN:
2666 {
2667 uint64_t ts;
2668
dd5a0db3 2669 ret = ops->timestamp_begin(config, buf, &ts);
3b731ab1
JD		 2670 if (ret < 0)
2671 goto error;
2672 return put_u64(ts, arg);
2673 }
2674 case LTTNG_RING_BUFFER_GET_TIMESTAMP_END:
2675 {
2676 uint64_t ts;
2677
dd5a0db3 2678 ret = ops->timestamp_end(config, buf, &ts);
3b731ab1
JD		 2679 if (ret < 0)
2680 goto error;
2681 return put_u64(ts, arg);
2682 }
2683 case LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED:
2684 {
2685 uint64_t ed;
2686
dd5a0db3 2687 ret = ops->events_discarded(config, buf, &ed);
3b731ab1
JD		 2688 if (ret < 0)
2689 goto error;
2690 return put_u64(ed, arg);
2691 }
2692 case LTTNG_RING_BUFFER_GET_CONTENT_SIZE:
2693 {
2694 uint64_t cs;
2695
dd5a0db3 2696 ret = ops->content_size(config, buf, &cs);
3b731ab1
JD		 2697 if (ret < 0)
2698 goto error;
2699 return put_u64(cs, arg);
2700 }
2701 case LTTNG_RING_BUFFER_GET_PACKET_SIZE:
2702 {
2703 uint64_t ps;
2704
dd5a0db3 2705 ret = ops->packet_size(config, buf, &ps);
3b731ab1
JD		 2706 if (ret < 0)
2707 goto error;
2708 return put_u64(ps, arg);
2709 }
2710 case LTTNG_RING_BUFFER_GET_STREAM_ID:
2711 {
2712 uint64_t si;
2713
dd5a0db3 2714 ret = ops->stream_id(config, buf, &si);
3b731ab1
JD		 2715 if (ret < 0)
2716 goto error;
2717 return put_u64(si, arg);
2718 }
2348ca17
JD		 2719 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
2720 {
2721 uint64_t ts;
2722
dd5a0db3 2723 ret = ops->current_timestamp(config, buf, &ts);
2348ca17
JD		 2724 if (ret < 0)
2725 goto error;
2726 return put_u64(ts, arg);
2727 }
5b3cf4f9
JD		 2728 case LTTNG_RING_BUFFER_GET_SEQ_NUM:
2729 {
2730 uint64_t seq;
2731
2732 ret = ops->sequence_number(config, buf, &seq);
2733 if (ret < 0)
2734 goto error;
2735 return put_u64(seq, arg);
2736 }
5594698f
JD		 2737 case LTTNG_RING_BUFFER_INSTANCE_ID:
2738 {
2739 uint64_t id;
2740
2741 ret = ops->instance_id(config, buf, &id);
2742 if (ret < 0)
2743 goto error;
2744 return put_u64(id, arg);
2745 }
3b731ab1
JD		 2746 default:
2747 return lib_ring_buffer_file_operations.unlocked_ioctl(filp,
2748 cmd, arg);
ed8d02d6 2749 }
3b731ab1
JD		 2750
2751error:
2752 return -ENOSYS;
ed8d02d6
JD		 2753}
2754
2755#ifdef CONFIG_COMPAT
2756static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
2757 unsigned int cmd, unsigned long arg)
2758{
3b731ab1
JD		 2759 struct lib_ring_buffer *buf = filp->private_data;
2760 struct channel *chan = buf->backend.chan;
2761 const struct lib_ring_buffer_config *config = &chan->backend.config;
dd5a0db3 2762 const struct lttng_channel_ops *ops = chan->backend.priv_ops;
3b731ab1
JD		 2763 int ret;
2764
2765 if (atomic_read(&chan->record_disabled))
2766 return -EIO;
2767
ed8d02d6 2768 switch (cmd) {
3b731ab1
JD		 2769 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_BEGIN:
2770 {
2771 uint64_t ts;
2772
dd5a0db3 2773 ret = ops->timestamp_begin(config, buf, &ts);
3b731ab1
JD		 2774 if (ret < 0)
2775 goto error;
2776 return put_u64(ts, arg);
2777 }
2778 case LTTNG_RING_BUFFER_COMPAT_GET_TIMESTAMP_END:
2779 {
2780 uint64_t ts;
2781
dd5a0db3 2782 ret = ops->timestamp_end(config, buf, &ts);
3b731ab1
JD		 2783 if (ret < 0)
2784 goto error;
2785 return put_u64(ts, arg);
2786 }
2787 case LTTNG_RING_BUFFER_COMPAT_GET_EVENTS_DISCARDED:
2788 {
2789 uint64_t ed;
2790
dd5a0db3 2791 ret = ops->events_discarded(config, buf, &ed);
3b731ab1
JD		 2792 if (ret < 0)
2793 goto error;
2794 return put_u64(ed, arg);
ed8d02d6 2795 }
3b731ab1
JD		 2796 case LTTNG_RING_BUFFER_COMPAT_GET_CONTENT_SIZE:
2797 {
2798 uint64_t cs;
2799
dd5a0db3 2800 ret = ops->content_size(config, buf, &cs);
3b731ab1
JD		 2801 if (ret < 0)
2802 goto error;
2803 return put_u64(cs, arg);
2804 }
2805 case LTTNG_RING_BUFFER_COMPAT_GET_PACKET_SIZE:
2806 {
2807 uint64_t ps;
2808
dd5a0db3 2809 ret = ops->packet_size(config, buf, &ps);
3b731ab1
JD		 2810 if (ret < 0)
2811 goto error;
2812 return put_u64(ps, arg);
2813 }
2814 case LTTNG_RING_BUFFER_COMPAT_GET_STREAM_ID:
2815 {
2816 uint64_t si;
2817
dd5a0db3 2818 ret = ops->stream_id(config, buf, &si);
3b731ab1
JD		 2819 if (ret < 0)
2820 goto error;
2821 return put_u64(si, arg);
2822 }
2348ca17
JD		 2823 case LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP:
2824 {
2825 uint64_t ts;
2826
dd5a0db3 2827 ret = ops->current_timestamp(config, buf, &ts);
2348ca17
JD		 2828 if (ret < 0)
2829 goto error;
2830 return put_u64(ts, arg);
2831 }
5b3cf4f9
JD		 2832 case LTTNG_RING_BUFFER_COMPAT_GET_SEQ_NUM:
2833 {
2834 uint64_t seq;
2835
2836 ret = ops->sequence_number(config, buf, &seq);
2837 if (ret < 0)
2838 goto error;
2839 return put_u64(seq, arg);
2840 }
5594698f
JD		 2841 case LTTNG_RING_BUFFER_COMPAT_INSTANCE_ID:
2842 {
2843 uint64_t id;
2844
2845 ret = ops->instance_id(config, buf, &id);
2846 if (ret < 0)
2847 goto error;
2848 return put_u64(id, arg);
2849 }
3b731ab1
JD		 2850 default:
2851 return lib_ring_buffer_file_operations.compat_ioctl(filp,
2852 cmd, arg);
2853 }
2854
2855error:
2856 return -ENOSYS;
ed8d02d6
JD		 2857}
2858#endif /* CONFIG_COMPAT */
2859
2860static void lttng_stream_override_ring_buffer_fops(void)
2861{
2862 lttng_stream_ring_buffer_file_operations.owner = THIS_MODULE;
2863 lttng_stream_ring_buffer_file_operations.open =
2864 lib_ring_buffer_file_operations.open;
2865 lttng_stream_ring_buffer_file_operations.release =
2866 lib_ring_buffer_file_operations.release;
2867 lttng_stream_ring_buffer_file_operations.poll =
2868 lib_ring_buffer_file_operations.poll;
2869 lttng_stream_ring_buffer_file_operations.splice_read =
2870 lib_ring_buffer_file_operations.splice_read;
2871 lttng_stream_ring_buffer_file_operations.mmap =
2872 lib_ring_buffer_file_operations.mmap;
2873 lttng_stream_ring_buffer_file_operations.unlocked_ioctl =
2874 lttng_stream_ring_buffer_ioctl;
2875 lttng_stream_ring_buffer_file_operations.llseek =
2876 lib_ring_buffer_file_operations.llseek;
2877#ifdef CONFIG_COMPAT
2878 lttng_stream_ring_buffer_file_operations.compat_ioctl =
2879 lttng_stream_ring_buffer_compat_ioctl;
2880#endif
2881}
2882
80996790 2883int __init lttng_abi_init(void)
baf20995
MD		 2884{
2885 int ret = 0;
2886
263b6c88 2887 wrapper_vmalloc_sync_mappings();
2754583e 2888 lttng_clock_ref();
f771eda6
JD		 2889
2890 ret = lttng_tp_mempool_init();
2891 if (ret) {
2892 goto error;
2893 }
2894
d29348f7 2895 lttng_proc_dentry = proc_create_data("lttng", S_IRUSR | S_IWUSR, NULL,
059de147 2896 &lttng_proc_ops, NULL);
2470a237 2897
255e52a4 2898 if (!lttng_proc_dentry) {
5a15f70c 2899 printk(KERN_ERR "LTTng: Error creating control file\n");
baf20995
MD		 2900 ret = -ENOMEM;
2901 goto error;
2902 }
ed8d02d6 2903 lttng_stream_override_ring_buffer_fops();
2754583e 2904 return 0;
ed8d02d6 2905
baf20995 2906error:
f771eda6 2907 lttng_tp_mempool_destroy();
2754583e 2908 lttng_clock_unref();
baf20995
MD		 2909 return ret;
2910}
2911
e6e65fcd
MD		 2912/* No __exit annotation because used by init error path too. */
2913void lttng_abi_exit(void)
baf20995 2914{
f771eda6 2915 lttng_tp_mempool_destroy();
2754583e 2916 lttng_clock_unref();
e6a17f26
MD		 2917 if (lttng_proc_dentry)
2918 remove_proc_entry("lttng", NULL);
baf20995 2919}
LTTng 2.0/0.x modules
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