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  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #define _GNU_SOURCE
  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
  26 #include "kernel-ctl.h"
  27 #include "kernel-ioctl.h"
  28
  29 /*
  30  * This flag indicates which version of the kernel ABI to use. The old
  31  * ABI (namespace _old) does not support a 32-bit user-space when the
  32  * kernel is 64-bit. The old ABI is kept here for compatibility but is
  33  * deprecated and will be removed eventually.
  34  */
  35 static int lttng_kernel_use_old_abi = -1;
  36
  37 /*
  38  * Execute the new or old ioctl depending on the ABI version.
  39  * If the ABI version is not determined yet (lttng_kernel_use_old_abi = -1),
  40  * this function tests if the new ABI is available and otherwise fallbacks
  41  * on the old one.
  42  * This function takes the fd on which the ioctl must be executed and the old
  43  * and new request codes.
  44  * It returns the return value of the ioctl executed.
  45  */
  46 static inline int compat_ioctl_no_arg(int fd, unsigned long oldname,
  47                 unsigned long newname)
  48 {
  49         int ret;
  50
  51         if (lttng_kernel_use_old_abi == -1) {
  52                 ret = ioctl(fd, newname);
  53                 if (!ret) {
  54                         lttng_kernel_use_old_abi = 0;
  55                         goto end;
  56                 }
  57                 lttng_kernel_use_old_abi = 1;
  58         }
  59         if (lttng_kernel_use_old_abi) {
  60                 ret = ioctl(fd, oldname);
  61         } else {
  62                 ret = ioctl(fd, newname);
  63         }
  64
  65 end:
  66         return ret;
  67 }
  68
  69 int kernctl_create_session(int fd)
  70 {
  71         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION,
  72                         LTTNG_KERNEL_SESSION);
  73 }
  74
  75 /* open the metadata global channel */
  76 int kernctl_open_metadata(int fd, struct lttng_channel_attr *chops)
  77 {
  78         struct lttng_kernel_old_channel old_channel;
  79         struct lttng_kernel_channel channel;
  80
  81         if (lttng_kernel_use_old_abi) {
  82                 old_channel.overwrite = chops->overwrite;
  83                 old_channel.subbuf_size = chops->subbuf_size;
  84                 old_channel.num_subbuf = chops->num_subbuf;
  85                 old_channel.switch_timer_interval = chops->switch_timer_interval;
  86                 old_channel.read_timer_interval = chops->read_timer_interval;
  87                 old_channel.output = chops->output;
  88
  89                 memset(old_channel.padding, 0, sizeof(old_channel.padding));
  90                 /*
  91                  * The new channel padding is smaller than the old ABI so we use the
  92                  * new ABI padding size for the memcpy.
  93                  */
  94                 memcpy(old_channel.padding, chops->padding, sizeof(chops->padding));
  95
  96                 return ioctl(fd, LTTNG_KERNEL_OLD_METADATA, &old_channel);
  97         }
  98
  99         channel.overwrite = chops->overwrite;
 100         channel.subbuf_size = chops->subbuf_size;
 101         channel.num_subbuf = chops->num_subbuf;
 102         channel.switch_timer_interval = chops->switch_timer_interval;
 103         channel.read_timer_interval = chops->read_timer_interval;
 104         channel.output = chops->output;
 105         memcpy(channel.padding, chops->padding, sizeof(chops->padding));
 106
 107         return ioctl(fd, LTTNG_KERNEL_METADATA, &channel);
 108 }
 109
 110 int kernctl_create_channel(int fd, struct lttng_channel_attr *chops)
 111 {
 112         struct lttng_kernel_channel channel;
 113
 114         if (lttng_kernel_use_old_abi) {
 115                 struct lttng_kernel_old_channel old_channel;
 116
 117                 old_channel.overwrite = chops->overwrite;
 118                 old_channel.subbuf_size = chops->subbuf_size;
 119                 old_channel.num_subbuf = chops->num_subbuf;
 120                 old_channel.switch_timer_interval = chops->switch_timer_interval;
 121                 old_channel.read_timer_interval = chops->read_timer_interval;
 122                 old_channel.output = chops->output;
 123
 124                 memset(old_channel.padding, 0, sizeof(old_channel.padding));
 125                 /*
 126                  * The new channel padding is smaller than the old ABI so we use the
 127                  * new ABI padding size for the memcpy.
 128                  */
 129                 memcpy(old_channel.padding, chops->padding, sizeof(chops->padding));
 130
 131                 return ioctl(fd, LTTNG_KERNEL_OLD_CHANNEL, &old_channel);
 132         }
 133
 134         channel.overwrite = chops->overwrite;
 135         channel.subbuf_size = chops->subbuf_size;
 136         channel.num_subbuf = chops->num_subbuf;
 137         channel.switch_timer_interval = chops->switch_timer_interval;
 138         channel.read_timer_interval = chops->read_timer_interval;
 139         channel.output = chops->output;
 140         memcpy(channel.padding, chops->padding, sizeof(chops->padding));
 141
 142         return ioctl(fd, LTTNG_KERNEL_CHANNEL, &channel);
 143 }
 144
 145 int kernctl_enable_syscall(int fd, const char *syscall_name)
 146 {
 147         struct lttng_kernel_event event;
 148
 149         memset(&event, 0, sizeof(event));
 150         strncpy(event.name, syscall_name, sizeof(event.name));
 151         event.name[sizeof(event.name) - 1] = '\0';
 152         event.instrumentation = LTTNG_KERNEL_SYSCALL;
 153         event.u.syscall.enable = 1;
 154         return ioctl(fd, LTTNG_KERNEL_EVENT, &event);
 155 }
 156
 157 int kernctl_disable_syscall(int fd, const char *syscall_name)
 158 {
 159         struct lttng_kernel_event event;
 160
 161         memset(&event, 0, sizeof(event));
 162         strncpy(event.name, syscall_name, sizeof(event.name));
 163         event.name[sizeof(event.name) - 1] = '\0';
 164         event.instrumentation = LTTNG_KERNEL_SYSCALL;
 165         event.u.syscall.enable = 0;
 166         return ioctl(fd, LTTNG_KERNEL_EVENT, &event);
 167 }
 168
 169 int kernctl_syscall_mask(int fd, char **syscall_mask, uint32_t *nr_bits)
 170 {
 171         struct lttng_kernel_syscall_mask kmask_len, *kmask = NULL;
 172         size_t array_alloc_len;
 173         char *new_mask;
 174         int ret = 0;
 175
 176         if (!syscall_mask) {
 177                 ret = -1;
 178                 goto end;
 179         }
 180
 181         if (!nr_bits) {
 182                 ret = -1;
 183                 goto end;
 184         }
 185
 186         kmask_len.len = 0;
 187         ret = ioctl(fd, LTTNG_KERNEL_SYSCALL_MASK, &kmask_len);
 188         if (ret) {
 189                 goto end;
 190         }
 191
 192         array_alloc_len = ALIGN(kmask_len.len, 8) >> 3;
 193
 194         kmask = zmalloc(sizeof(*kmask) + array_alloc_len);
 195         if (!kmask) {
 196                 ret = -1;
 197                 goto end;
 198         }
 199
 200         kmask->len = kmask_len.len;
 201         ret = ioctl(fd, LTTNG_KERNEL_SYSCALL_MASK, kmask);
 202         if (ret) {
 203                 goto end;
 204         }
 205
 206         new_mask = realloc(*syscall_mask, array_alloc_len);
 207         if (!new_mask) {
 208                 ret = -1;
 209                 goto end;
 210         }
 211         memcpy(new_mask, kmask->mask, array_alloc_len);
 212         *syscall_mask = new_mask;
 213         *nr_bits = kmask->len;
 214
 215 end:
 216         free(kmask);
 217         return ret;
 218 }
 219
 220 int kernctl_create_stream(int fd)
 221 {
 222         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_STREAM,
 223                         LTTNG_KERNEL_STREAM);
 224 }
 225
 226 int kernctl_create_event(int fd, struct lttng_kernel_event *ev)
 227 {
 228         if (lttng_kernel_use_old_abi) {
 229                 struct lttng_kernel_old_event old_event;
 230
 231                 memcpy(old_event.name, ev->name, sizeof(old_event.name));
 232                 old_event.instrumentation = ev->instrumentation;
 233                 switch (ev->instrumentation) {
 234                 case LTTNG_KERNEL_KPROBE:
 235                         old_event.u.kprobe.addr = ev->u.kprobe.addr;
 236                         old_event.u.kprobe.offset = ev->u.kprobe.offset;
 237                         memcpy(old_event.u.kprobe.symbol_name,
 238                                 ev->u.kprobe.symbol_name,
 239                                 sizeof(old_event.u.kprobe.symbol_name));
 240                         break;
 241                 case LTTNG_KERNEL_KRETPROBE:
 242                         old_event.u.kretprobe.addr = ev->u.kretprobe.addr;
 243                         old_event.u.kretprobe.offset = ev->u.kretprobe.offset;
 244                         memcpy(old_event.u.kretprobe.symbol_name,
 245                                 ev->u.kretprobe.symbol_name,
 246                                 sizeof(old_event.u.kretprobe.symbol_name));
 247                         break;
 248                 case LTTNG_KERNEL_FUNCTION:
 249                         memcpy(old_event.u.ftrace.symbol_name,
 250                                         ev->u.ftrace.symbol_name,
 251                                         sizeof(old_event.u.ftrace.symbol_name));
 252                         break;
 253                 default:
 254                         break;
 255                 }
 256
 257                 return ioctl(fd, LTTNG_KERNEL_OLD_EVENT, &old_event);
 258         }
 259         return ioctl(fd, LTTNG_KERNEL_EVENT, ev);
 260 }
 261
 262 int kernctl_add_context(int fd, struct lttng_kernel_context *ctx)
 263 {
 264         if (lttng_kernel_use_old_abi) {
 265                 struct lttng_kernel_old_context old_ctx;
 266
 267                 old_ctx.ctx = ctx->ctx;
 268                 /* only type that uses the union */
 269                 if (ctx->ctx == LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER) {
 270                         old_ctx.u.perf_counter.type =
 271                                 ctx->u.perf_counter.type;
 272                         old_ctx.u.perf_counter.config =
 273                                 ctx->u.perf_counter.config;
 274                         memcpy(old_ctx.u.perf_counter.name,
 275                                 ctx->u.perf_counter.name,
 276                                 sizeof(old_ctx.u.perf_counter.name));
 277                 }
 278                 return ioctl(fd, LTTNG_KERNEL_OLD_CONTEXT, &old_ctx);
 279         }
 280         return ioctl(fd, LTTNG_KERNEL_CONTEXT, ctx);
 281 }
 282
 283
 284 /* Enable event, channel and session ioctl */
 285 int kernctl_enable(int fd)
 286 {
 287         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_ENABLE,
 288                         LTTNG_KERNEL_ENABLE);
 289 }
 290
 291 /* Disable event, channel and session ioctl */
 292 int kernctl_disable(int fd)
 293 {
 294         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_DISABLE,
 295                         LTTNG_KERNEL_DISABLE);
 296 }
 297
 298 int kernctl_start_session(int fd)
 299 {
 300         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_START,
 301                         LTTNG_KERNEL_SESSION_START);
 302 }
 303
 304 int kernctl_stop_session(int fd)
 305 {
 306         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_STOP,
 307                         LTTNG_KERNEL_SESSION_STOP);
 308 }
 309
 310 int kernctl_tracepoint_list(int fd)
 311 {
 312         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_TRACEPOINT_LIST,
 313                         LTTNG_KERNEL_TRACEPOINT_LIST);
 314 }
 315
 316 int kernctl_syscall_list(int fd)
 317 {
 318         return ioctl(fd, LTTNG_KERNEL_SYSCALL_LIST);
 319 }
 320
 321 int kernctl_tracer_version(int fd, struct lttng_kernel_tracer_version *v)
 322 {
 323         int ret;
 324
 325         if (lttng_kernel_use_old_abi == -1) {
 326                 ret = ioctl(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 327                 if (!ret) {
 328                         lttng_kernel_use_old_abi = 0;
 329                         goto end;
 330                 }
 331                 lttng_kernel_use_old_abi = 1;
 332         }
 333         if (lttng_kernel_use_old_abi) {
 334                 struct lttng_kernel_old_tracer_version old_v;
 335
 336                 ret = ioctl(fd, LTTNG_KERNEL_OLD_TRACER_VERSION, &old_v);
 337                 if (ret) {
 338                         goto end;
 339                 }
 340                 v->major = old_v.major;
 341                 v->minor = old_v.minor;
 342                 v->patchlevel = old_v.patchlevel;
 343         } else {
 344                 ret = ioctl(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 345         }
 346
 347 end:
 348         return ret;
 349 }
 350
 351 int kernctl_tracer_abi_version(int fd,
 352                 struct lttng_kernel_tracer_abi_version *v)
 353 {
 354         return ioctl(fd, LTTNG_KERNEL_TRACER_ABI_VERSION, v);
 355 }
 356
 357 int kernctl_wait_quiescent(int fd)
 358 {
 359         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_WAIT_QUIESCENT,
 360                         LTTNG_KERNEL_WAIT_QUIESCENT);
 361 }
 362
 363 int kernctl_calibrate(int fd, struct lttng_kernel_calibrate *calibrate)
 364 {
 365         int ret;
 366
 367         if (lttng_kernel_use_old_abi == -1) {
 368                 ret = ioctl(fd, LTTNG_KERNEL_CALIBRATE, calibrate);
 369                 if (!ret) {
 370                         lttng_kernel_use_old_abi = 0;
 371                         goto end;
 372                 }
 373                 lttng_kernel_use_old_abi = 1;
 374         }
 375         if (lttng_kernel_use_old_abi) {
 376                 struct lttng_kernel_old_calibrate old_calibrate;
 377
 378                 old_calibrate.type = calibrate->type;
 379                 ret = ioctl(fd, LTTNG_KERNEL_OLD_CALIBRATE, &old_calibrate);
 380                 if (ret) {
 381                         goto end;
 382                 }
 383                 calibrate->type = old_calibrate.type;
 384         } else {
 385                 ret = ioctl(fd, LTTNG_KERNEL_CALIBRATE, calibrate);
 386         }
 387
 388 end:
 389         return ret;
 390 }
 391
 392
 393 int kernctl_buffer_flush(int fd)
 394 {
 395         return ioctl(fd, RING_BUFFER_FLUSH);
 396 }
 397
 398
 399 /* Buffer operations */
 400
 401 /* For mmap mode, readable without "get" operation */
 402
 403 /* returns the length to mmap. */
 404 int kernctl_get_mmap_len(int fd, unsigned long *len)
 405 {
 406         return ioctl(fd, RING_BUFFER_GET_MMAP_LEN, len);
 407 }
 408
 409 /* returns the maximum size for sub-buffers. */
 410 int kernctl_get_max_subbuf_size(int fd, unsigned long *len)
 411 {
 412         return ioctl(fd, RING_BUFFER_GET_MAX_SUBBUF_SIZE, len);
 413 }
 414
 415 /*
 416  * For mmap mode, operate on the current packet (between get/put or
 417  * get_next/put_next).
 418  */
 419
 420 /* returns the offset of the subbuffer belonging to the mmap reader. */
 421 int kernctl_get_mmap_read_offset(int fd, unsigned long *off)
 422 {
 423         return ioctl(fd, RING_BUFFER_GET_MMAP_READ_OFFSET, off);
 424 }
 425
 426 /* returns the size of the current sub-buffer, without padding (for mmap). */
 427 int kernctl_get_subbuf_size(int fd, unsigned long *len)
 428 {
 429         return ioctl(fd, RING_BUFFER_GET_SUBBUF_SIZE, len);
 430 }
 431
 432 /* returns the size of the current sub-buffer, without padding (for mmap). */
 433 int kernctl_get_padded_subbuf_size(int fd, unsigned long *len)
 434 {
 435         return ioctl(fd, RING_BUFFER_GET_PADDED_SUBBUF_SIZE, len);
 436 }
 437
 438 /* Get exclusive read access to the next sub-buffer that can be read. */
 439 int kernctl_get_next_subbuf(int fd)
 440 {
 441         return ioctl(fd, RING_BUFFER_GET_NEXT_SUBBUF);
 442 }
 443
 444
 445 /* Release exclusive sub-buffer access, move consumer forward. */
 446 int kernctl_put_next_subbuf(int fd)
 447 {
 448         return ioctl(fd, RING_BUFFER_PUT_NEXT_SUBBUF);
 449 }
 450
 451 /* snapshot */
 452
 453 /* Get a snapshot of the current ring buffer producer and consumer positions */
 454 int kernctl_snapshot(int fd)
 455 {
 456         return ioctl(fd, RING_BUFFER_SNAPSHOT);
 457 }
 458
 459 /* Get the consumer position (iteration start) */
 460 int kernctl_snapshot_get_consumed(int fd, unsigned long *pos)
 461 {
 462         return ioctl(fd, RING_BUFFER_SNAPSHOT_GET_CONSUMED, pos);
 463 }
 464
 465 /* Get the producer position (iteration end) */
 466 int kernctl_snapshot_get_produced(int fd, unsigned long *pos)
 467 {
 468         return ioctl(fd, RING_BUFFER_SNAPSHOT_GET_PRODUCED, pos);
 469 }
 470
 471 /* Get exclusive read access to the specified sub-buffer position */
 472 int kernctl_get_subbuf(int fd, unsigned long *len)
 473 {
 474         return ioctl(fd, RING_BUFFER_GET_SUBBUF, len);
 475 }
 476
 477 /* Release exclusive sub-buffer access */
 478 int kernctl_put_subbuf(int fd)
 479 {
 480         return ioctl(fd, RING_BUFFER_PUT_SUBBUF);
 481 }
 482
 483 /* Returns the timestamp begin of the current sub-buffer. */
 484 int kernctl_get_timestamp_begin(int fd, uint64_t *timestamp_begin)
 485 {
 486         return ioctl(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN, timestamp_begin);
 487 }
 488
 489 /* Returns the timestamp end of the current sub-buffer. */
 490 int kernctl_get_timestamp_end(int fd, uint64_t *timestamp_end)
 491 {
 492         return ioctl(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_END, timestamp_end);
 493 }
 494
 495 /* Returns the number of discarded events in the current sub-buffer. */
 496 int kernctl_get_events_discarded(int fd, uint64_t *events_discarded)
 497 {
 498         return ioctl(fd, LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED, events_discarded);
 499 }
 500
 501 /* Returns the content size in the current sub-buffer. */
 502 int kernctl_get_content_size(int fd, uint64_t *content_size)
 503 {
 504         return ioctl(fd, LTTNG_RING_BUFFER_GET_CONTENT_SIZE, content_size);
 505 }
 506
 507 /* Returns the packet size in the current sub-buffer. */
 508 int kernctl_get_packet_size(int fd, uint64_t *packet_size)
 509 {
 510         return ioctl(fd, LTTNG_RING_BUFFER_GET_PACKET_SIZE, packet_size);
 511 }
 512
 513 /* Returns the stream id of the current sub-buffer. */
 514 int kernctl_get_stream_id(int fd, uint64_t *stream_id)
 515 {
 516         return ioctl(fd, LTTNG_RING_BUFFER_GET_STREAM_ID, stream_id);
 517 }
 518
 519 /* Returns the current timestamp. */
 520 int kernctl_get_current_timestamp(int fd, uint64_t *ts)
 521 {
 522         return ioctl(fd, LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP, ts);
 523 }