src/common/kernel-ctl/kernel-ctl.c

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *               2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #define _LGPL_SOURCE
  21 #define __USE_LINUX_IOCTL_DEFS
  22 #include <sys/ioctl.h>
  23 #include <string.h>
  24 #include <common/align.h>
  25 #include <errno.h>
  26 #include <stdarg.h>
  27 #include <assert.h>
  28
  29 #include "kernel-ctl.h"
  30 #include "kernel-ioctl.h"
  31
  32 #define LTTNG_IOCTL_CHECK(fildes, request, ...) ({      \
  33         int ret = ioctl(fildes, request, ##__VA_ARGS__);\
  34         assert(ret <= 0);                               \
  35         !ret ? 0 : -errno;                              \
  36 })
  37
  38 #define LTTNG_IOCTL_NO_CHECK(fildes, request, ...) ({   \
  39         int ret = ioctl(fildes, request, ##__VA_ARGS__);\
  40         ret >= 0 ? ret : -errno;                        \
  41 })
  42
  43 /*
  44  * This flag indicates which version of the kernel ABI to use. The old
  45  * ABI (namespace _old) does not support a 32-bit user-space when the
  46  * kernel is 64-bit. The old ABI is kept here for compatibility but is
  47  * deprecated and will be removed eventually.
  48  */
  49 static int lttng_kernel_use_old_abi = -1;
  50
  51 /*
  52  * Execute the new or old ioctl depending on the ABI version.
  53  * If the ABI version is not determined yet (lttng_kernel_use_old_abi = -1),
  54  * this function tests if the new ABI is available and otherwise fallbacks
  55  * on the old one.
  56  * This function takes the fd on which the ioctl must be executed and the old
  57  * and new request codes.
  58  * It returns the return value of the ioctl executed.
  59  */
  60 static inline int compat_ioctl_no_arg(int fd, unsigned long oldname,
  61                 unsigned long newname)
  62 {
  63         int ret;
  64
  65         if (lttng_kernel_use_old_abi == -1) {
  66                 ret = LTTNG_IOCTL_NO_CHECK(fd, newname);
  67                 if (!ret) {
  68                         lttng_kernel_use_old_abi = 0;
  69                         goto end;
  70                 }
  71                 lttng_kernel_use_old_abi = 1;
  72         }
  73         if (lttng_kernel_use_old_abi) {
  74                 ret = LTTNG_IOCTL_NO_CHECK(fd, oldname);
  75         } else {
  76                 ret = LTTNG_IOCTL_NO_CHECK(fd, newname);
  77         }
  78
  79 end:
  80         return ret;
  81 }
  82
  83 int kernctl_create_session(int fd)
  84 {
  85         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION,
  86                         LTTNG_KERNEL_SESSION);
  87 }
  88
  89 /* open the metadata global channel */
  90 int kernctl_open_metadata(int fd, struct lttng_channel_attr *chops)
  91 {
  92         struct lttng_kernel_channel channel;
  93
  94         if (lttng_kernel_use_old_abi) {
  95                 struct lttng_kernel_old_channel old_channel;
  96
  97                 memset(&old_channel, 0, sizeof(old_channel));
  98                 old_channel.overwrite = chops->overwrite;
  99                 old_channel.subbuf_size = chops->subbuf_size;
 100                 old_channel.num_subbuf = chops->num_subbuf;
 101                 old_channel.switch_timer_interval = chops->switch_timer_interval;
 102                 old_channel.read_timer_interval = chops->read_timer_interval;
 103                 old_channel.output = chops->output;
 104
 105                 memset(old_channel.padding, 0, sizeof(old_channel.padding));
 106                 /*
 107                  * The new channel padding is smaller than the old ABI so we use the
 108                  * new ABI padding size for the memcpy.
 109                  */
 110                 memcpy(old_channel.padding, chops->padding, sizeof(chops->padding));
 111
 112                 return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_OLD_METADATA,
 113                                 &old_channel);
 114         }
 115
 116         memset(&channel, 0, sizeof(channel));
 117         channel.overwrite = chops->overwrite;
 118         channel.subbuf_size = chops->subbuf_size;
 119         channel.num_subbuf = chops->num_subbuf;
 120         channel.switch_timer_interval = chops->switch_timer_interval;
 121         channel.read_timer_interval = chops->read_timer_interval;
 122         channel.output = chops->output;
 123         memcpy(channel.padding, chops->padding, sizeof(chops->padding));
 124
 125         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_METADATA, &channel);
 126 }
 127
 128 int kernctl_create_channel(int fd, struct lttng_channel_attr *chops)
 129 {
 130         struct lttng_kernel_channel channel;
 131
 132         memset(&channel, 0, sizeof(channel));
 133         if (lttng_kernel_use_old_abi) {
 134                 struct lttng_kernel_old_channel old_channel;
 135
 136                 old_channel.overwrite = chops->overwrite;
 137                 old_channel.subbuf_size = chops->subbuf_size;
 138                 old_channel.num_subbuf = chops->num_subbuf;
 139                 old_channel.switch_timer_interval = chops->switch_timer_interval;
 140                 old_channel.read_timer_interval = chops->read_timer_interval;
 141                 old_channel.output = chops->output;
 142
 143                 memset(old_channel.padding, 0, sizeof(old_channel.padding));
 144                 /*
 145                  * The new channel padding is smaller than the old ABI so we use the
 146                  * new ABI padding size for the memcpy.
 147                  */
 148                 memcpy(old_channel.padding, chops->padding, sizeof(chops->padding));
 149
 150                 return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_OLD_CHANNEL,
 151                                 &old_channel);
 152         }
 153
 154         channel.overwrite = chops->overwrite;
 155         channel.subbuf_size = chops->subbuf_size;
 156         channel.num_subbuf = chops->num_subbuf;
 157         channel.switch_timer_interval = chops->switch_timer_interval;
 158         channel.read_timer_interval = chops->read_timer_interval;
 159         channel.output = chops->output;
 160         memcpy(channel.padding, chops->padding, sizeof(chops->padding));
 161
 162         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_CHANNEL, &channel);
 163 }
 164
 165 int kernctl_syscall_mask(int fd, char **syscall_mask, uint32_t *nr_bits)
 166 {
 167         struct lttng_kernel_syscall_mask kmask_len, *kmask = NULL;
 168         size_t array_alloc_len;
 169         char *new_mask;
 170         int ret = 0;
 171
 172         if (!syscall_mask) {
 173                 ret = -1;
 174                 goto end;
 175         }
 176
 177         if (!nr_bits) {
 178                 ret = -1;
 179                 goto end;
 180         }
 181
 182         kmask_len.len = 0;
 183         ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SYSCALL_MASK, &kmask_len);
 184         if (ret) {
 185                 goto end;
 186         }
 187
 188         array_alloc_len = ALIGN(kmask_len.len, 8) >> 3;
 189
 190         kmask = zmalloc(sizeof(*kmask) + array_alloc_len);
 191         if (!kmask) {
 192                 ret = -1;
 193                 goto end;
 194         }
 195
 196         kmask->len = kmask_len.len;
 197         ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SYSCALL_MASK, kmask);
 198         if (ret) {
 199                 goto end;
 200         }
 201
 202         new_mask = realloc(*syscall_mask, array_alloc_len);
 203         if (!new_mask) {
 204                 ret = -1;
 205                 goto end;
 206         }
 207         memcpy(new_mask, kmask->mask, array_alloc_len);
 208         *syscall_mask = new_mask;
 209         *nr_bits = kmask->len;
 210
 211 end:
 212         free(kmask);
 213         return ret;
 214 }
 215
 216 int kernctl_track_pid(int fd, int pid)
 217 {
 218         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_TRACK_PID, pid);
 219 }
 220
 221 int kernctl_untrack_pid(int fd, int pid)
 222 {
 223         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_UNTRACK_PID, pid);
 224 }
 225
 226 int kernctl_list_tracker_pids(int fd)
 227 {
 228         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS);
 229 }
 230
 231 static
 232 enum lttng_kernel_tracker_type get_kernel_tracker_type(enum lttng_tracker_type type)
 233 {
 234         switch (type) {
 235         case LTTNG_TRACKER_PID:
 236                 return LTTNG_KERNEL_TRACKER_PID;
 237         case LTTNG_TRACKER_VPID:
 238                 return LTTNG_KERNEL_TRACKER_VPID;
 239         case LTTNG_TRACKER_UID:
 240                 return LTTNG_KERNEL_TRACKER_UID;
 241         case LTTNG_TRACKER_VUID:
 242                 return LTTNG_KERNEL_TRACKER_VUID;
 243         case LTTNG_TRACKER_GID:
 244                 return LTTNG_KERNEL_TRACKER_GID;
 245         case LTTNG_TRACKER_VGID:
 246                 return LTTNG_KERNEL_TRACKER_VGID;
 247         default:
 248                 return LTTNG_KERNEL_TRACKER_UNKNOWN;
 249         }
 250 }
 251
 252 int kernctl_track_id(int fd, enum lttng_tracker_type tracker_type, int id)
 253 {
 254         struct lttng_kernel_tracker_args args;
 255
 256         args.id = id;
 257         args.type = get_kernel_tracker_type(tracker_type);
 258         if (args.type == LTTNG_KERNEL_TRACKER_UNKNOWN) {
 259                 errno = EINVAL;
 260                 return -1;
 261         }
 262         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_TRACK_ID, &args);
 263 }
 264
 265 int kernctl_untrack_id(int fd, enum lttng_tracker_type tracker_type, int id)
 266 {
 267         struct lttng_kernel_tracker_args args;
 268
 269         args.id = id;
 270         args.type = get_kernel_tracker_type(tracker_type);
 271         if (args.type == LTTNG_KERNEL_TRACKER_UNKNOWN) {
 272                 errno = EINVAL;
 273                 return -1;
 274         }
 275         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_UNTRACK_ID, &args);
 276 }
 277
 278 int kernctl_list_tracker_ids(int fd, enum lttng_tracker_type tracker_type)
 279 {
 280         struct lttng_kernel_tracker_args args;
 281
 282         args.id = -1;
 283         args.type = get_kernel_tracker_type(tracker_type);
 284         if (args.type == LTTNG_KERNEL_TRACKER_UNKNOWN) {
 285                 errno = EINVAL;
 286                 return -1;
 287         }
 288         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_SESSION_LIST_TRACKER_IDS,
 289                         &args);
 290 }
 291
 292 int kernctl_session_regenerate_metadata(int fd)
 293 {
 294         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_METADATA_REGEN);
 295 }
 296
 297 int kernctl_session_regenerate_statedump(int fd)
 298 {
 299         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_SESSION_STATEDUMP);
 300 }
 301
 302 int kernctl_create_stream(int fd)
 303 {
 304         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_STREAM,
 305                         LTTNG_KERNEL_STREAM);
 306 }
 307
 308 int kernctl_create_event(int fd, struct lttng_kernel_event *ev)
 309 {
 310         if (lttng_kernel_use_old_abi) {
 311                 struct lttng_kernel_old_event old_event;
 312
 313                 memset(&old_event, 0, sizeof(old_event));
 314                 memcpy(old_event.name, ev->name, sizeof(old_event.name));
 315                 old_event.instrumentation = ev->instrumentation;
 316                 switch (ev->instrumentation) {
 317                 case LTTNG_KERNEL_KPROBE:
 318                         old_event.u.kprobe.addr = ev->u.kprobe.addr;
 319                         old_event.u.kprobe.offset = ev->u.kprobe.offset;
 320                         memcpy(old_event.u.kprobe.symbol_name,
 321                                 ev->u.kprobe.symbol_name,
 322                                 sizeof(old_event.u.kprobe.symbol_name));
 323                         break;
 324                 case LTTNG_KERNEL_KRETPROBE:
 325                         old_event.u.kretprobe.addr = ev->u.kretprobe.addr;
 326                         old_event.u.kretprobe.offset = ev->u.kretprobe.offset;
 327                         memcpy(old_event.u.kretprobe.symbol_name,
 328                                 ev->u.kretprobe.symbol_name,
 329                                 sizeof(old_event.u.kretprobe.symbol_name));
 330                         break;
 331                 case LTTNG_KERNEL_FUNCTION:
 332                         memcpy(old_event.u.ftrace.symbol_name,
 333                                         ev->u.ftrace.symbol_name,
 334                                         sizeof(old_event.u.ftrace.symbol_name));
 335                         break;
 336                 default:
 337                         break;
 338                 }
 339
 340                 return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_OLD_EVENT,
 341                                 &old_event);
 342         }
 343         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_EVENT, ev);
 344 }
 345
 346 int kernctl_add_context(int fd, struct lttng_kernel_context *ctx)
 347 {
 348         if (lttng_kernel_use_old_abi) {
 349                 struct lttng_kernel_old_context old_ctx;
 350
 351                 memset(&old_ctx, 0, sizeof(old_ctx));
 352                 old_ctx.ctx = ctx->ctx;
 353                 /* only type that uses the union */
 354                 if (ctx->ctx == LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER) {
 355                         old_ctx.u.perf_counter.type =
 356                                 ctx->u.perf_counter.type;
 357                         old_ctx.u.perf_counter.config =
 358                                 ctx->u.perf_counter.config;
 359                         memcpy(old_ctx.u.perf_counter.name,
 360                                 ctx->u.perf_counter.name,
 361                                 sizeof(old_ctx.u.perf_counter.name));
 362                 }
 363                 return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_OLD_CONTEXT, &old_ctx);
 364         }
 365         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_CONTEXT, ctx);
 366 }
 367
 368
 369 /* Enable event, channel and session LTTNG_IOCTL_CHECK */
 370 int kernctl_enable(int fd)
 371 {
 372         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_ENABLE,
 373                         LTTNG_KERNEL_ENABLE);
 374 }
 375
 376 /* Disable event, channel and session LTTNG_IOCTL_CHECK */
 377 int kernctl_disable(int fd)
 378 {
 379         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_DISABLE,
 380                         LTTNG_KERNEL_DISABLE);
 381 }
 382
 383 int kernctl_start_session(int fd)
 384 {
 385         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_START,
 386                         LTTNG_KERNEL_SESSION_START);
 387 }
 388
 389 int kernctl_stop_session(int fd)
 390 {
 391         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_STOP,
 392                         LTTNG_KERNEL_SESSION_STOP);
 393 }
 394
 395 int kernctl_filter(int fd, struct lttng_filter_bytecode *filter)
 396 {
 397         struct lttng_kernel_filter_bytecode *kb;
 398         uint32_t len;
 399         int ret;
 400
 401         /* Translate bytecode to kernel bytecode */
 402         kb = zmalloc(sizeof(*kb) + filter->len);
 403         if (!kb)
 404                 return -ENOMEM;
 405         kb->len = len = filter->len;
 406         kb->reloc_offset = filter->reloc_table_offset;
 407         kb->seqnum = filter->seqnum;
 408         memcpy(kb->data, filter->data, len);
 409         ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_FILTER, kb);
 410         free(kb);
 411         return ret;
 412 }
 413
 414 int kernctl_tracepoint_list(int fd)
 415 {
 416         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_TRACEPOINT_LIST,
 417                         LTTNG_KERNEL_TRACEPOINT_LIST);
 418 }
 419
 420 int kernctl_syscall_list(int fd)
 421 {
 422         return LTTNG_IOCTL_NO_CHECK(fd, LTTNG_KERNEL_SYSCALL_LIST);
 423 }
 424
 425 int kernctl_tracer_version(int fd, struct lttng_kernel_tracer_version *v)
 426 {
 427         int ret;
 428
 429         if (lttng_kernel_use_old_abi == -1) {
 430                 ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 431                 if (!ret) {
 432                         lttng_kernel_use_old_abi = 0;
 433                         goto end;
 434                 }
 435                 lttng_kernel_use_old_abi = 1;
 436         }
 437         if (lttng_kernel_use_old_abi) {
 438                 struct lttng_kernel_old_tracer_version old_v;
 439
 440                 ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_OLD_TRACER_VERSION, &old_v);
 441                 if (ret) {
 442                         goto end;
 443                 }
 444                 v->major = old_v.major;
 445                 v->minor = old_v.minor;
 446                 v->patchlevel = old_v.patchlevel;
 447         } else {
 448                 ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 449         }
 450
 451 end:
 452         return ret;
 453 }
 454
 455 int kernctl_tracer_abi_version(int fd,
 456                 struct lttng_kernel_tracer_abi_version *v)
 457 {
 458         return LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_TRACER_ABI_VERSION, v);
 459 }
 460
 461 int kernctl_wait_quiescent(int fd)
 462 {
 463         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_WAIT_QUIESCENT,
 464                         LTTNG_KERNEL_WAIT_QUIESCENT);
 465 }
 466
 467 int kernctl_buffer_flush(int fd)
 468 {
 469         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_FLUSH);
 470 }
 471
 472 int kernctl_buffer_flush_empty(int fd)
 473 {
 474         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_FLUSH_EMPTY);
 475 }
 476
 477 int kernctl_get_next_subbuf_metadata_check(int fd, bool *consistent)
 478 {
 479         return LTTNG_IOCTL_NO_CHECK(fd,
 480                         RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK,
 481                         consistent);
 482 }
 483
 484 /* returns the version of the metadata. */
 485 int kernctl_get_metadata_version(int fd, uint64_t *version)
 486 {
 487         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_METADATA_VERSION, version);
 488 }
 489
 490
 491 /* Buffer operations */
 492
 493 /* For mmap mode, readable without "get" operation */
 494
 495 /* returns the length to mmap. */
 496 int kernctl_get_mmap_len(int fd, unsigned long *len)
 497 {
 498         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_MMAP_LEN, len);
 499 }
 500
 501 /* returns the maximum size for sub-buffers. */
 502 int kernctl_get_max_subbuf_size(int fd, unsigned long *len)
 503 {
 504         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_MAX_SUBBUF_SIZE, len);
 505 }
 506
 507 /*
 508  * For mmap mode, operate on the current packet (between get/put or
 509  * get_next/put_next).
 510  */
 511
 512 /* returns the offset of the subbuffer belonging to the mmap reader. */
 513 int kernctl_get_mmap_read_offset(int fd, unsigned long *off)
 514 {
 515         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_MMAP_READ_OFFSET, off);
 516 }
 517
 518 /* returns the size of the current sub-buffer, without padding (for mmap). */
 519 int kernctl_get_subbuf_size(int fd, unsigned long *len)
 520 {
 521         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_SUBBUF_SIZE, len);
 522 }
 523
 524 /* returns the size of the current sub-buffer, without padding (for mmap). */
 525 int kernctl_get_padded_subbuf_size(int fd, unsigned long *len)
 526 {
 527         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_PADDED_SUBBUF_SIZE, len);
 528 }
 529
 530 /* Get exclusive read access to the next sub-buffer that can be read. */
 531 int kernctl_get_next_subbuf(int fd)
 532 {
 533         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_NEXT_SUBBUF);
 534 }
 535
 536
 537 /* Release exclusive sub-buffer access, move consumer forward. */
 538 int kernctl_put_next_subbuf(int fd)
 539 {
 540         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_PUT_NEXT_SUBBUF);
 541 }
 542
 543 /* snapshot */
 544
 545 /* Get a snapshot of the current ring buffer producer and consumer positions */
 546 int kernctl_snapshot(int fd)
 547 {
 548         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_SNAPSHOT);
 549 }
 550
 551 /* Get the consumer position (iteration start) */
 552 int kernctl_snapshot_get_consumed(int fd, unsigned long *pos)
 553 {
 554         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_SNAPSHOT_GET_CONSUMED, pos);
 555 }
 556
 557 /* Get the producer position (iteration end) */
 558 int kernctl_snapshot_get_produced(int fd, unsigned long *pos)
 559 {
 560         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_SNAPSHOT_GET_PRODUCED, pos);
 561 }
 562
 563 /* Get exclusive read access to the specified sub-buffer position */
 564 int kernctl_get_subbuf(int fd, unsigned long *len)
 565 {
 566         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_GET_SUBBUF, len);
 567 }
 568
 569 /* Release exclusive sub-buffer access */
 570 int kernctl_put_subbuf(int fd)
 571 {
 572         return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_PUT_SUBBUF);
 573 }
 574
 575 /* Returns the timestamp begin of the current sub-buffer. */
 576 int kernctl_get_timestamp_begin(int fd, uint64_t *timestamp_begin)
 577 {
 578         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN,
 579                         timestamp_begin);
 580 }
 581
 582 /* Returns the timestamp end of the current sub-buffer. */
 583 int kernctl_get_timestamp_end(int fd, uint64_t *timestamp_end)
 584 {
 585         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_END,
 586                         timestamp_end);
 587 }
 588
 589 /* Returns the number of discarded events in the current sub-buffer. */
 590 int kernctl_get_events_discarded(int fd, uint64_t *events_discarded)
 591 {
 592         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED,
 593                         events_discarded);
 594 }
 595
 596 /* Returns the content size in the current sub-buffer. */
 597 int kernctl_get_content_size(int fd, uint64_t *content_size)
 598 {
 599         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_CONTENT_SIZE,
 600                         content_size);
 601 }
 602
 603 /* Returns the packet size in the current sub-buffer. */
 604 int kernctl_get_packet_size(int fd, uint64_t *packet_size)
 605 {
 606         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_PACKET_SIZE,
 607                         packet_size);
 608 }
 609
 610 /* Returns the stream id of the current sub-buffer. */
 611 int kernctl_get_stream_id(int fd, uint64_t *stream_id)
 612 {
 613         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_STREAM_ID,
 614                         stream_id);
 615 }
 616
 617 /* Returns the current timestamp. */
 618 int kernctl_get_current_timestamp(int fd, uint64_t *ts)
 619 {
 620         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP,
 621                         ts);
 622 }
 623
 624 /* Returns the packet sequence number of the current sub-buffer. */
 625 int kernctl_get_sequence_number(int fd, uint64_t *seq)
 626 {
 627         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_GET_SEQ_NUM, seq);
 628 }
 629
 630 /* Returns the stream instance id. */
 631 int kernctl_get_instance_id(int fd, uint64_t *id)
 632 {
 633         return LTTNG_IOCTL_CHECK(fd, LTTNG_RING_BUFFER_INSTANCE_ID, id);
 634 }