liblttng-ust-ctl/ustctl.c

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; only version 2
   8  * of the License.
   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
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18  */
  19
  20 #include <string.h>
  21 #include <lttng/ust-ctl.h>
  22 #include <lttng/ust-abi.h>
  23 #include <lttng/ust-events.h>
  24 #include <sys/mman.h>
  25
  26 #include <usterr-signal-safe.h>
  27 #include <ust-comm.h>
  28
  29 #include "../libringbuffer/backend.h"
  30 #include "../libringbuffer/frontend.h"
  31
  32 volatile enum ust_loglevel ust_loglevel;
  33
  34 static
  35 void init_object(struct lttng_ust_object_data *data)
  36 {
  37         data->handle = -1;
  38         data->shm_fd = -1;
  39         data->wait_fd = -1;
  40         data->memory_map_size = 0;
  41 }
  42
  43 int ustctl_release_handle(int sock, int handle)
  44 {
  45         struct ustcomm_ust_msg lum;
  46         struct ustcomm_ust_reply lur;
  47         int ret;
  48
  49         if (sock >= 0) {
  50                 memset(&lum, 0, sizeof(lum));
  51                 lum.handle = handle;
  52                 lum.cmd = LTTNG_UST_RELEASE;
  53                 ret = ustcomm_send_app_cmd(sock, &lum, &lur);
  54                 if (ret < 0) {
  55                         return ret;
  56                 }
  57         }
  58         return 0;
  59 }
  60 /*
  61  * If sock is negative, it means we don't have to notify the other side
  62  * (e.g. application has already vanished).
  63  */
  64 int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
  65 {
  66         int ret;
  67
  68         if (data->shm_fd >= 0) {
  69                 ret = close(data->shm_fd);
  70                 if (ret < 0) {
  71                         return ret;
  72                 }
  73         }
  74         if (data->wait_fd >= 0) {
  75                 ret = close(data->wait_fd);
  76                 if (ret < 0) {
  77                         return ret;
  78                 }
  79         }
  80         return ustctl_release_handle(sock, data->handle);
  81 }
  82
  83 /*
  84  * Send registration done packet to the application.
  85  */
  86 int ustctl_register_done(int sock)
  87 {
  88         struct ustcomm_ust_msg lum;
  89         struct ustcomm_ust_reply lur;
  90         int ret;
  91
  92         DBG("Sending register done command to %d", sock);
  93         memset(&lum, 0, sizeof(lum));
  94         lum.handle = LTTNG_UST_ROOT_HANDLE;
  95         lum.cmd = LTTNG_UST_REGISTER_DONE;
  96         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
  97         if (ret)
  98                 return ret;
  99         if (lur.ret_code != USTCOMM_OK) {
 100                 DBG("Return code: %s", ustcomm_get_readable_code(lur.ret_code));
 101                 goto error;
 102         }
 103         return 0;
 104
 105 error:
 106         return -1;
 107 }
 108
 109 /*
 110  * returns session handle.
 111  */
 112 int ustctl_create_session(int sock)
 113 {
 114         struct ustcomm_ust_msg lum;
 115         struct ustcomm_ust_reply lur;
 116         int ret, session_handle;
 117
 118         /* Create session */
 119         memset(&lum, 0, sizeof(lum));
 120         lum.handle = LTTNG_UST_ROOT_HANDLE;
 121         lum.cmd = LTTNG_UST_SESSION;
 122         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 123         if (ret)
 124                 return ret;
 125         session_handle = lur.ret_val;
 126         DBG("received session handle %u", session_handle);
 127         return session_handle;
 128 }
 129
 130 /* open the metadata global channel */
 131 int ustctl_open_metadata(int sock, int session_handle,
 132                 struct lttng_ust_channel_attr *chops,
 133                 struct lttng_ust_object_data **_metadata_data)
 134 {
 135         struct ustcomm_ust_msg lum;
 136         struct ustcomm_ust_reply lur;
 137         struct lttng_ust_object_data *metadata_data;
 138         int ret, err = 0;
 139
 140         metadata_data = malloc(sizeof(*metadata_data));
 141         if (!metadata_data)
 142                 return -ENOMEM;
 143         init_object(metadata_data);
 144         /* Create metadata channel */
 145         memset(&lum, 0, sizeof(lum));
 146         lum.handle = session_handle;
 147         lum.cmd = LTTNG_UST_METADATA;
 148         lum.u.channel.overwrite = chops->overwrite;
 149         lum.u.channel.subbuf_size = chops->subbuf_size;
 150         lum.u.channel.num_subbuf = chops->num_subbuf;
 151         lum.u.channel.switch_timer_interval = chops->switch_timer_interval;
 152         lum.u.channel.read_timer_interval = chops->read_timer_interval;
 153         lum.u.channel.output = chops->output;
 154         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 155         if (ret) {
 156                 free(metadata_data);
 157                 return ret;
 158         }
 159         if (lur.ret_code != USTCOMM_OK) {
 160                 free(metadata_data);
 161                 return lur.ret_code;
 162         }
 163         metadata_data->handle = lur.ret_val;
 164         DBG("received metadata handle %u", metadata_data->handle);
 165         metadata_data->memory_map_size = lur.u.channel.memory_map_size;
 166         /* get shm fd */
 167         ret = ustcomm_recv_fd(sock);
 168         if (ret < 0)
 169                 err = 1;
 170         else
 171                 metadata_data->shm_fd = ret;
 172         /*
 173          * We need to get the second FD even if the first fails, because
 174          * libust expects us to read the two FDs.
 175          */
 176         /* get wait fd */
 177         ret = ustcomm_recv_fd(sock);
 178         if (ret < 0)
 179                 err = 1;
 180         else
 181                 metadata_data->wait_fd = ret;
 182         if (err)
 183                 goto error;
 184         *_metadata_data = metadata_data;
 185         return 0;
 186
 187 error:
 188         (void) ustctl_release_object(sock, metadata_data);
 189         free(metadata_data);
 190         return -EINVAL;
 191 }
 192
 193 int ustctl_create_channel(int sock, int session_handle,
 194                 struct lttng_ust_channel_attr *chops,
 195                 struct lttng_ust_object_data **_channel_data)
 196 {
 197         struct ustcomm_ust_msg lum;
 198         struct ustcomm_ust_reply lur;
 199         struct lttng_ust_object_data *channel_data;
 200         int ret, err = 0;
 201
 202         channel_data = malloc(sizeof(*channel_data));
 203         if (!channel_data)
 204                 return -ENOMEM;
 205         init_object(channel_data);
 206         /* Create metadata channel */
 207         memset(&lum, 0, sizeof(lum));
 208         lum.handle = session_handle;
 209         lum.cmd = LTTNG_UST_CHANNEL;
 210         lum.u.channel.overwrite = chops->overwrite;
 211         lum.u.channel.subbuf_size = chops->subbuf_size;
 212         lum.u.channel.num_subbuf = chops->num_subbuf;
 213         lum.u.channel.switch_timer_interval = chops->switch_timer_interval;
 214         lum.u.channel.read_timer_interval = chops->read_timer_interval;
 215         lum.u.channel.output = chops->output;
 216         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 217         if (ret) {
 218                 free(channel_data);
 219                 return ret;
 220         }
 221         if (lur.ret_code != USTCOMM_OK) {
 222                 free(channel_data);
 223                 return lur.ret_code;
 224         }
 225         channel_data->handle = lur.ret_val;
 226         DBG("received channel handle %u", channel_data->handle);
 227         channel_data->memory_map_size = lur.u.channel.memory_map_size;
 228         /* get shm fd */
 229         ret = ustcomm_recv_fd(sock);
 230         if (ret < 0)
 231                 err = 1;
 232         else
 233                 channel_data->shm_fd = ret;
 234         /*
 235          * We need to get the second FD even if the first fails, because
 236          * libust expects us to read the two FDs.
 237          */
 238         /* get wait fd */
 239         ret = ustcomm_recv_fd(sock);
 240         if (ret < 0)
 241                 err = 1;
 242         else
 243                 channel_data->wait_fd = ret;
 244         if (err)
 245                 goto error;
 246         *_channel_data = channel_data;
 247         return 0;
 248
 249 error:
 250         (void) ustctl_release_object(sock, channel_data);
 251         free(channel_data);
 252         return -EINVAL;
 253 }
 254
 255 /*
 256  * Return -ENOENT if no more stream is available for creation.
 257  * Return 0 on success.
 258  * Return negative error value on error.
 259  */
 260 int ustctl_create_stream(int sock, struct lttng_ust_object_data *channel_data,
 261                 struct lttng_ust_object_data **_stream_data)
 262 {
 263         struct ustcomm_ust_msg lum;
 264         struct ustcomm_ust_reply lur;
 265         struct lttng_ust_object_data *stream_data;
 266         int ret, fd, err = 0;
 267
 268         stream_data = malloc(sizeof(*stream_data));
 269         if (!stream_data)
 270                 return -ENOMEM;
 271         init_object(stream_data);
 272         memset(&lum, 0, sizeof(lum));
 273         lum.handle = channel_data->handle;
 274         lum.cmd = LTTNG_UST_STREAM;
 275         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 276         if (ret) {
 277                 free(stream_data);
 278                 return ret;
 279         }
 280         if (lur.ret_code != USTCOMM_OK) {
 281                 free(stream_data);
 282                 return lur.ret_code;
 283         }
 284
 285         stream_data->handle = lur.ret_val;
 286         DBG("received stream handle %u", stream_data->handle);
 287         stream_data->memory_map_size = lur.u.stream.memory_map_size;
 288         /* get shm fd */
 289         fd = ustcomm_recv_fd(sock);
 290         if (fd < 0)
 291                 err = 1;
 292         else
 293                 stream_data->shm_fd = fd;
 294         /*
 295          * We need to get the second FD even if the first fails, because
 296          * libust expects us to read the two FDs.
 297          */
 298         /* get wait fd */
 299         fd = ustcomm_recv_fd(sock);
 300         if (fd < 0)
 301                 err = 1;
 302         else
 303                 stream_data->wait_fd = fd;
 304         if (err)
 305                 goto error;
 306         *_stream_data = stream_data;
 307         return ret;
 308
 309 error:
 310         (void) ustctl_release_object(sock, stream_data);
 311         free(stream_data);
 312         return -EINVAL;
 313 }
 314
 315 int ustctl_create_event(int sock, struct lttng_ust_event *ev,
 316                 struct lttng_ust_object_data *channel_data,
 317                 struct lttng_ust_object_data **_event_data)
 318 {
 319         struct ustcomm_ust_msg lum;
 320         struct ustcomm_ust_reply lur;
 321         struct lttng_ust_object_data *event_data;
 322         int ret;
 323
 324         event_data = malloc(sizeof(*event_data));
 325         if (!event_data)
 326                 return -ENOMEM;
 327         init_object(event_data);
 328         memset(&lum, 0, sizeof(lum));
 329         lum.handle = channel_data->handle;
 330         lum.cmd = LTTNG_UST_EVENT;
 331         strncpy(lum.u.event.name, ev->name,
 332                 LTTNG_UST_SYM_NAME_LEN);
 333         lum.u.event.instrumentation = ev->instrumentation;
 334         lum.u.event.loglevel_type = ev->loglevel_type;
 335         lum.u.event.loglevel = ev->loglevel;
 336         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 337         if (ret) {
 338                 free(event_data);
 339                 return ret;
 340         }
 341         event_data->handle = lur.ret_val;
 342         DBG("received event handle %u", event_data->handle);
 343         *_event_data = event_data;
 344         return 0;
 345 }
 346
 347 int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
 348                 struct lttng_ust_object_data *obj_data,
 349                 struct lttng_ust_object_data **_context_data)
 350 {
 351         struct ustcomm_ust_msg lum;
 352         struct ustcomm_ust_reply lur;
 353         struct lttng_ust_object_data *context_data;
 354         int ret;
 355
 356         context_data = malloc(sizeof(*context_data));
 357         if (!context_data)
 358                 return -ENOMEM;
 359         init_object(context_data);
 360         memset(&lum, 0, sizeof(lum));
 361         lum.handle = obj_data->handle;
 362         lum.cmd = LTTNG_UST_CONTEXT;
 363         lum.u.context.ctx = ctx->ctx;
 364         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 365         if (ret) {
 366                 free(context_data);
 367                 return ret;
 368         }
 369         context_data->handle = lur.ret_val;
 370         DBG("received context handle %u", context_data->handle);
 371         *_context_data = context_data;
 372         return ret;
 373 }
 374
 375 /* Enable event, channel and session ioctl */
 376 int ustctl_enable(int sock, struct lttng_ust_object_data *object)
 377 {
 378         struct ustcomm_ust_msg lum;
 379         struct ustcomm_ust_reply lur;
 380         int ret;
 381
 382         memset(&lum, 0, sizeof(lum));
 383         lum.handle = object->handle;
 384         lum.cmd = LTTNG_UST_ENABLE;
 385         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 386         if (ret)
 387                 return ret;
 388         DBG("enabled handle %u", object->handle);
 389         return 0;
 390 }
 391
 392 /* Disable event, channel and session ioctl */
 393 int ustctl_disable(int sock, struct lttng_ust_object_data *object)
 394 {
 395         struct ustcomm_ust_msg lum;
 396         struct ustcomm_ust_reply lur;
 397         int ret;
 398
 399         memset(&lum, 0, sizeof(lum));
 400         lum.handle = object->handle;
 401         lum.cmd = LTTNG_UST_DISABLE;
 402         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 403         if (ret)
 404                 return ret;
 405         DBG("disable handle %u", object->handle);
 406         return 0;
 407 }
 408
 409 int ustctl_start_session(int sock, int handle)
 410 {
 411         struct lttng_ust_object_data obj;
 412
 413         obj.handle = handle;
 414         return ustctl_enable(sock, &obj);
 415 }
 416
 417 int ustctl_stop_session(int sock, int handle)
 418 {
 419         struct lttng_ust_object_data obj;
 420
 421         obj.handle = handle;
 422         return ustctl_disable(sock, &obj);
 423 }
 424
 425 int ustctl_tracepoint_list(int sock)
 426 {
 427         struct ustcomm_ust_msg lum;
 428         struct ustcomm_ust_reply lur;
 429         int ret, tp_list_handle;
 430
 431         memset(&lum, 0, sizeof(lum));
 432         lum.handle = LTTNG_UST_ROOT_HANDLE;
 433         lum.cmd = LTTNG_UST_TRACEPOINT_LIST;
 434         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 435         if (ret)
 436                 return ret;
 437         tp_list_handle = lur.ret_val;
 438         DBG("received tracepoint list handle %u", tp_list_handle);
 439         return tp_list_handle;
 440 }
 441
 442 int ustctl_tracepoint_list_get(int sock, int tp_list_handle,
 443                 struct lttng_ust_tracepoint_iter *iter)
 444 {
 445         struct ustcomm_ust_msg lum;
 446         struct ustcomm_ust_reply lur;
 447         int ret;
 448
 449         memset(&lum, 0, sizeof(lum));
 450         lum.handle = tp_list_handle;
 451         lum.cmd = LTTNG_UST_TRACEPOINT_LIST_GET;
 452         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 453         if (ret)
 454                 return ret;
 455         DBG("received tracepoint list entry name %s loglevel %d",
 456                 lur.u.tracepoint.name,
 457                 lur.u.tracepoint.loglevel);
 458         memcpy(iter, &lur.u.tracepoint, sizeof(*iter));
 459         return 0;
 460 }
 461
 462 int ustctl_tracer_version(int sock, struct lttng_ust_tracer_version *v)
 463 {
 464         struct ustcomm_ust_msg lum;
 465         struct ustcomm_ust_reply lur;
 466         int ret;
 467
 468         memset(&lum, 0, sizeof(lum));
 469         lum.handle = LTTNG_UST_ROOT_HANDLE;
 470         lum.cmd = LTTNG_UST_TRACER_VERSION;
 471         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 472         if (ret)
 473                 return ret;
 474         memcpy(v, &lur.u.version, sizeof(*v));
 475         DBG("received tracer version");
 476         return 0;
 477 }
 478
 479 int ustctl_wait_quiescent(int sock)
 480 {
 481         struct ustcomm_ust_msg lum;
 482         struct ustcomm_ust_reply lur;
 483         int ret;
 484
 485         memset(&lum, 0, sizeof(lum));
 486         lum.handle = LTTNG_UST_ROOT_HANDLE;
 487         lum.cmd = LTTNG_UST_WAIT_QUIESCENT;
 488         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 489         if (ret)
 490                 return ret;
 491         DBG("waited for quiescent state");
 492         return 0;
 493 }
 494
 495 int ustctl_calibrate(int sock, struct lttng_ust_calibrate *calibrate)
 496 {
 497         return -ENOSYS;
 498 }
 499
 500 int ustctl_sock_flush_buffer(int sock, struct lttng_ust_object_data *object)
 501 {
 502         struct ustcomm_ust_msg lum;
 503         struct ustcomm_ust_reply lur;
 504         int ret;
 505
 506         memset(&lum, 0, sizeof(lum));
 507         lum.handle = object->handle;
 508         lum.cmd = LTTNG_UST_FLUSH_BUFFER;
 509         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 510         if (ret)
 511                 return ret;
 512         DBG("flushed buffer handle %u", object->handle);
 513         return 0;
 514 }
 515
 516 /* Buffer operations */
 517
 518 /* Map channel shm into process memory */
 519 struct lttng_ust_shm_handle *ustctl_map_channel(struct lttng_ust_object_data *chan_data)
 520 {
 521         struct lttng_ust_shm_handle *handle;
 522         struct channel *chan;
 523         size_t chan_size;
 524         struct lttng_ust_lib_ring_buffer_config *config;
 525         int ret;
 526
 527         handle = channel_handle_create(chan_data->shm_fd,
 528                 chan_data->wait_fd,
 529                 chan_data->memory_map_size);
 530         if (!handle) {
 531                 ERR("create handle error");
 532                 return NULL;
 533         }
 534         /*
 535          * Set to -1, and then close the shm fd, and set the handle shm
 536          * fd to -1 too. We don't need the shm fds after they have been
 537          * mapped.
 538          * The wait_fd is set to -1 in chan_data because it is now owned
 539          * by the handle.
 540          */
 541         chan_data->shm_fd = -1;
 542         chan_data->wait_fd = -1;
 543
 544         /* chan is object 0. This is hardcoded. */
 545         if (handle->table->objects[0].shm_fd >= 0) {
 546                 ret = close(handle->table->objects[0].shm_fd);
 547                 if (ret) {
 548                         perror("Error closing shm_fd");
 549                 }
 550                 handle->table->objects[0].shm_fd = -1;
 551         }
 552
 553         /*
 554          * TODO: add consistency checks to be resilient if the
 555          * application try to feed us with incoherent channel structure
 556          * values.
 557          */
 558         chan = shmp(handle, handle->chan);
 559         /* chan is object 0. This is hardcoded. */
 560         chan_size = handle->table->objects[0].allocated_len;
 561         handle->shadow_chan = malloc(chan_size);
 562         if (!handle->shadow_chan) {
 563                 channel_destroy(chan, handle, 1);
 564                 return NULL;
 565         }
 566         memcpy(handle->shadow_chan, chan, chan_size);
 567         /*
 568          * The callback pointers in the producer are invalid in the
 569          * consumer. We need to look them up here.
 570          */
 571         config = &handle->shadow_chan->backend.config;
 572         switch (config->client_type) {
 573         case LTTNG_CLIENT_METADATA:
 574                 memcpy(&config->cb, lttng_client_callbacks_metadata,
 575                         sizeof(config->cb));
 576                 break;
 577         case LTTNG_CLIENT_DISCARD:
 578                 memcpy(&config->cb, lttng_client_callbacks_discard,
 579                         sizeof(config->cb));
 580                 break;
 581         case LTTNG_CLIENT_OVERWRITE:
 582                 memcpy(&config->cb, lttng_client_callbacks_overwrite,
 583                         sizeof(config->cb));
 584                 break;
 585         default:
 586                 ERR("Unknown client type %d", config->client_type);
 587                 channel_destroy(chan, handle, 1);
 588                 return NULL;
 589         }
 590         /* Replace the object table pointer. */
 591         ret = munmap(handle->table->objects[0].memory_map,
 592                 handle->table->objects[0].memory_map_size);
 593         if (ret) {
 594                 perror("munmap");
 595                 assert(0);
 596         }
 597         handle->table->objects[0].memory_map = (char *) handle->shadow_chan;
 598         handle->table->objects[0].is_shadow = 1;
 599         return handle;
 600 }
 601
 602 /* Add stream to channel shm and map its shm into process memory */
 603 int ustctl_add_stream(struct lttng_ust_shm_handle *handle,
 604                 struct lttng_ust_object_data *stream_data)
 605 {
 606         int ret;
 607
 608         if (!stream_data->handle)
 609                 return -ENOENT;
 610         /* map stream */
 611         ret = channel_handle_add_stream(handle,
 612                 stream_data->shm_fd,
 613                 stream_data->wait_fd,
 614                 stream_data->memory_map_size);
 615         if (ret) {
 616                 ERR("add stream error\n");
 617                 return ret;
 618         }
 619         /*
 620          * Set to -1 because the lttng_ust_shm_handle destruction will take care
 621          * of closing shm_fd and wait_fd.
 622          */
 623         stream_data->shm_fd = -1;
 624         stream_data->wait_fd = -1;
 625         return 0;
 626 }
 627
 628 void ustctl_unmap_channel(struct lttng_ust_shm_handle *handle)
 629 {
 630         struct channel *chan;
 631
 632         chan = shmp(handle, handle->chan);
 633         channel_destroy(chan, handle, 1);
 634 }
 635
 636 /*
 637  * ustctl closes the shm_fd fds after mapping it.
 638  */
 639 struct lttng_ust_lib_ring_buffer *ustctl_open_stream_read(struct lttng_ust_shm_handle *handle,
 640         int cpu)
 641 {
 642         struct channel *chan = handle->shadow_chan;
 643         int *shm_fd, *wait_fd;
 644         uint64_t *memory_map_size;
 645         struct lttng_ust_lib_ring_buffer *buf;
 646         int ret;
 647
 648         buf = channel_get_ring_buffer(&chan->backend.config,
 649                 chan, cpu, handle, &shm_fd, &wait_fd, &memory_map_size);
 650         if (!buf)
 651                 return NULL;
 652         ret = lib_ring_buffer_open_read(buf, handle, 1);
 653         if (ret)
 654                 return NULL;
 655         /*
 656          * We can close shm_fd early, right after is has been mapped.
 657          */
 658         if (*shm_fd >= 0) {
 659                 ret = close(*shm_fd);
 660                 if (ret) {
 661                         perror("Error closing shm_fd");
 662                 }
 663                 *shm_fd = -1;
 664         }
 665         return buf;
 666 }
 667
 668 void ustctl_close_stream_read(struct lttng_ust_shm_handle *handle,
 669                 struct lttng_ust_lib_ring_buffer *buf)
 670 {
 671         lib_ring_buffer_release_read(buf, handle, 1);
 672 }
 673
 674 /* For mmap mode, readable without "get" operation */
 675
 676 void *ustctl_get_mmap_base(struct lttng_ust_shm_handle *handle,
 677                 struct lttng_ust_lib_ring_buffer *buf)
 678 {
 679         return shmp(handle, buf->backend.memory_map);
 680 }
 681
 682 /* returns the length to mmap. */
 683 int ustctl_get_mmap_len(struct lttng_ust_shm_handle *handle,
 684                 struct lttng_ust_lib_ring_buffer *buf,
 685                 unsigned long *len)
 686 {
 687         unsigned long mmap_buf_len;
 688         struct channel *chan = handle->shadow_chan;
 689
 690         if (chan->backend.config.output != RING_BUFFER_MMAP)
 691                 return -EINVAL;
 692         mmap_buf_len = chan->backend.buf_size;
 693         if (chan->backend.extra_reader_sb)
 694                 mmap_buf_len += chan->backend.subbuf_size;
 695         if (mmap_buf_len > INT_MAX)
 696                 return -EFBIG;
 697         *len = mmap_buf_len;
 698         return 0;
 699 }
 700
 701 /* returns the maximum size for sub-buffers. */
 702 int ustctl_get_max_subbuf_size(struct lttng_ust_shm_handle *handle,
 703                 struct lttng_ust_lib_ring_buffer *buf,
 704                 unsigned long *len)
 705 {
 706         struct channel *chan = handle->shadow_chan;
 707
 708         *len = chan->backend.subbuf_size;
 709         return 0;
 710 }
 711
 712 /*
 713  * For mmap mode, operate on the current packet (between get/put or
 714  * get_next/put_next).
 715  */
 716
 717 /* returns the offset of the subbuffer belonging to the mmap reader. */
 718 int ustctl_get_mmap_read_offset(struct lttng_ust_shm_handle *handle,
 719                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *off)
 720 {
 721         struct channel *chan = handle->shadow_chan;
 722         unsigned long sb_bindex;
 723
 724         if (chan->backend.config.output != RING_BUFFER_MMAP)
 725                 return -EINVAL;
 726         sb_bindex = subbuffer_id_get_index(&chan->backend.config,
 727                                            buf->backend.buf_rsb.id);
 728         *off = shmp(handle, shmp_index(handle, buf->backend.array, sb_bindex)->shmp)->mmap_offset;
 729         return 0;
 730 }
 731
 732 /* returns the size of the current sub-buffer, without padding (for mmap). */
 733 int ustctl_get_subbuf_size(struct lttng_ust_shm_handle *handle,
 734                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *len)
 735 {
 736         struct channel *chan = handle->shadow_chan;
 737
 738         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
 739                 handle);
 740         return 0;
 741 }
 742
 743 /* returns the size of the current sub-buffer, without padding (for mmap). */
 744 int ustctl_get_padded_subbuf_size(struct lttng_ust_shm_handle *handle,
 745                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *len)
 746 {
 747         struct channel *chan = handle->shadow_chan;
 748
 749         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
 750                 handle);
 751         *len = PAGE_ALIGN(*len);
 752         return 0;
 753 }
 754
 755 /* Get exclusive read access to the next sub-buffer that can be read. */
 756 int ustctl_get_next_subbuf(struct lttng_ust_shm_handle *handle,
 757                 struct lttng_ust_lib_ring_buffer *buf)
 758 {
 759         return lib_ring_buffer_get_next_subbuf(buf, handle);
 760 }
 761
 762
 763 /* Release exclusive sub-buffer access, move consumer forward. */
 764 int ustctl_put_next_subbuf(struct lttng_ust_shm_handle *handle,
 765                 struct lttng_ust_lib_ring_buffer *buf)
 766 {
 767         lib_ring_buffer_put_next_subbuf(buf, handle);
 768         return 0;
 769 }
 770
 771 /* snapshot */
 772
 773 /* Get a snapshot of the current ring buffer producer and consumer positions */
 774 int ustctl_snapshot(struct lttng_ust_shm_handle *handle,
 775                 struct lttng_ust_lib_ring_buffer *buf)
 776 {
 777         return lib_ring_buffer_snapshot(buf, &buf->cons_snapshot,
 778                         &buf->prod_snapshot, handle);
 779 }
 780
 781 /* Get the consumer position (iteration start) */
 782 int ustctl_snapshot_get_consumed(struct lttng_ust_shm_handle *handle,
 783                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *pos)
 784 {
 785         *pos = buf->cons_snapshot;
 786         return 0;
 787 }
 788
 789 /* Get the producer position (iteration end) */
 790 int ustctl_snapshot_get_produced(struct lttng_ust_shm_handle *handle,
 791                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *pos)
 792 {
 793         *pos = buf->prod_snapshot;
 794         return 0;
 795 }
 796
 797 /* Get exclusive read access to the specified sub-buffer position */
 798 int ustctl_get_subbuf(struct lttng_ust_shm_handle *handle,
 799                 struct lttng_ust_lib_ring_buffer *buf, unsigned long *pos)
 800 {
 801         return lib_ring_buffer_get_subbuf(buf, *pos, handle);
 802 }
 803
 804 /* Release exclusive sub-buffer access */
 805 int ustctl_put_subbuf(struct lttng_ust_shm_handle *handle,
 806                 struct lttng_ust_lib_ring_buffer *buf)
 807 {
 808         lib_ring_buffer_put_subbuf(buf, handle);
 809         return 0;
 810 }
 811
 812 void ustctl_flush_buffer(struct lttng_ust_shm_handle *handle,
 813                 struct lttng_ust_lib_ring_buffer *buf,
 814                 int producer_active)
 815 {
 816         lib_ring_buffer_switch_slow(buf,
 817                 producer_active ? SWITCH_ACTIVE : SWITCH_FLUSH,
 818                 handle);
 819 }