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