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_syscall_mask(int fd, char **syscall_mask, uint32_t *nr_bits)
 146 {
 147         struct lttng_kernel_syscall_mask kmask_len, *kmask = NULL;
 148         size_t array_alloc_len;
 149         char *new_mask;
 150         int ret = 0;
 151
 152         if (!syscall_mask) {
 153                 ret = -1;
 154                 goto end;
 155         }
 156
 157         if (!nr_bits) {
 158                 ret = -1;
 159                 goto end;
 160         }
 161
 162         kmask_len.len = 0;
 163         ret = ioctl(fd, LTTNG_KERNEL_SYSCALL_MASK, &kmask_len);
 164         if (ret) {
 165                 goto end;
 166         }
 167
 168         array_alloc_len = ALIGN(kmask_len.len, 8) >> 3;
 169
 170         kmask = zmalloc(sizeof(*kmask) + array_alloc_len);
 171         if (!kmask) {
 172                 ret = -1;
 173                 goto end;
 174         }
 175
 176         kmask->len = kmask_len.len;
 177         ret = ioctl(fd, LTTNG_KERNEL_SYSCALL_MASK, kmask);
 178         if (ret) {
 179                 goto end;
 180         }
 181
 182         new_mask = realloc(*syscall_mask, array_alloc_len);
 183         if (!new_mask) {
 184                 ret = -1;
 185                 goto end;
 186         }
 187         memcpy(new_mask, kmask->mask, array_alloc_len);
 188         *syscall_mask = new_mask;
 189         *nr_bits = kmask->len;
 190
 191 end:
 192         free(kmask);
 193         return ret;
 194 }
 195
 196 int kernctl_track_pid(int fd, int pid)
 197 {
 198         return ioctl(fd, LTTNG_KERNEL_SESSION_TRACK_PID, pid);
 199 }
 200
 201 int kernctl_untrack_pid(int fd, int pid)
 202 {
 203         return ioctl(fd, LTTNG_KERNEL_SESSION_UNTRACK_PID, pid);
 204 }
 205
 206 int kernctl_list_tracker_pids(int fd)
 207 {
 208         return ioctl(fd, LTTNG_KERNEL_SESSION_LIST_TRACKER_PIDS);
 209 }
 210
 211 int kernctl_create_stream(int fd)
 212 {
 213         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_STREAM,
 214                         LTTNG_KERNEL_STREAM);
 215 }
 216
 217 int kernctl_create_event(int fd, struct lttng_kernel_event *ev)
 218 {
 219         if (lttng_kernel_use_old_abi) {
 220                 struct lttng_kernel_old_event old_event;
 221
 222                 memcpy(old_event.name, ev->name, sizeof(old_event.name));
 223                 old_event.instrumentation = ev->instrumentation;
 224                 switch (ev->instrumentation) {
 225                 case LTTNG_KERNEL_KPROBE:
 226                         old_event.u.kprobe.addr = ev->u.kprobe.addr;
 227                         old_event.u.kprobe.offset = ev->u.kprobe.offset;
 228                         memcpy(old_event.u.kprobe.symbol_name,
 229                                 ev->u.kprobe.symbol_name,
 230                                 sizeof(old_event.u.kprobe.symbol_name));
 231                         break;
 232                 case LTTNG_KERNEL_KRETPROBE:
 233                         old_event.u.kretprobe.addr = ev->u.kretprobe.addr;
 234                         old_event.u.kretprobe.offset = ev->u.kretprobe.offset;
 235                         memcpy(old_event.u.kretprobe.symbol_name,
 236                                 ev->u.kretprobe.symbol_name,
 237                                 sizeof(old_event.u.kretprobe.symbol_name));
 238                         break;
 239                 case LTTNG_KERNEL_FUNCTION:
 240                         memcpy(old_event.u.ftrace.symbol_name,
 241                                         ev->u.ftrace.symbol_name,
 242                                         sizeof(old_event.u.ftrace.symbol_name));
 243                         break;
 244                 default:
 245                         break;
 246                 }
 247
 248                 return ioctl(fd, LTTNG_KERNEL_OLD_EVENT, &old_event);
 249         }
 250         return ioctl(fd, LTTNG_KERNEL_EVENT, ev);
 251 }
 252
 253 int kernctl_add_context(int fd, struct lttng_kernel_context *ctx)
 254 {
 255         if (lttng_kernel_use_old_abi) {
 256                 struct lttng_kernel_old_context old_ctx;
 257
 258                 old_ctx.ctx = ctx->ctx;
 259                 /* only type that uses the union */
 260                 if (ctx->ctx == LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER) {
 261                         old_ctx.u.perf_counter.type =
 262                                 ctx->u.perf_counter.type;
 263                         old_ctx.u.perf_counter.config =
 264                                 ctx->u.perf_counter.config;
 265                         memcpy(old_ctx.u.perf_counter.name,
 266                                 ctx->u.perf_counter.name,
 267                                 sizeof(old_ctx.u.perf_counter.name));
 268                 }
 269                 return ioctl(fd, LTTNG_KERNEL_OLD_CONTEXT, &old_ctx);
 270         }
 271         return ioctl(fd, LTTNG_KERNEL_CONTEXT, ctx);
 272 }
 273
 274
 275 /* Enable event, channel and session ioctl */
 276 int kernctl_enable(int fd)
 277 {
 278         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_ENABLE,
 279                         LTTNG_KERNEL_ENABLE);
 280 }
 281
 282 /* Disable event, channel and session ioctl */
 283 int kernctl_disable(int fd)
 284 {
 285         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_DISABLE,
 286                         LTTNG_KERNEL_DISABLE);
 287 }
 288
 289 int kernctl_start_session(int fd)
 290 {
 291         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_START,
 292                         LTTNG_KERNEL_SESSION_START);
 293 }
 294
 295 int kernctl_stop_session(int fd)
 296 {
 297         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_SESSION_STOP,
 298                         LTTNG_KERNEL_SESSION_STOP);
 299 }
 300
 301 int kernctl_tracepoint_list(int fd)
 302 {
 303         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_TRACEPOINT_LIST,
 304                         LTTNG_KERNEL_TRACEPOINT_LIST);
 305 }
 306
 307 int kernctl_syscall_list(int fd)
 308 {
 309         return ioctl(fd, LTTNG_KERNEL_SYSCALL_LIST);
 310 }
 311
 312 int kernctl_tracer_version(int fd, struct lttng_kernel_tracer_version *v)
 313 {
 314         int ret;
 315
 316         if (lttng_kernel_use_old_abi == -1) {
 317                 ret = ioctl(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 318                 if (!ret) {
 319                         lttng_kernel_use_old_abi = 0;
 320                         goto end;
 321                 }
 322                 lttng_kernel_use_old_abi = 1;
 323         }
 324         if (lttng_kernel_use_old_abi) {
 325                 struct lttng_kernel_old_tracer_version old_v;
 326
 327                 ret = ioctl(fd, LTTNG_KERNEL_OLD_TRACER_VERSION, &old_v);
 328                 if (ret) {
 329                         goto end;
 330                 }
 331                 v->major = old_v.major;
 332                 v->minor = old_v.minor;
 333                 v->patchlevel = old_v.patchlevel;
 334         } else {
 335                 ret = ioctl(fd, LTTNG_KERNEL_TRACER_VERSION, v);
 336         }
 337
 338 end:
 339         return ret;
 340 }
 341
 342 int kernctl_tracer_abi_version(int fd,
 343                 struct lttng_kernel_tracer_abi_version *v)
 344 {
 345         return ioctl(fd, LTTNG_KERNEL_TRACER_ABI_VERSION, v);
 346 }
 347
 348 int kernctl_wait_quiescent(int fd)
 349 {
 350         return compat_ioctl_no_arg(fd, LTTNG_KERNEL_OLD_WAIT_QUIESCENT,
 351                         LTTNG_KERNEL_WAIT_QUIESCENT);
 352 }
 353
 354 int kernctl_calibrate(int fd, struct lttng_kernel_calibrate *calibrate)
 355 {
 356         int ret;
 357
 358         if (lttng_kernel_use_old_abi == -1) {
 359                 ret = ioctl(fd, LTTNG_KERNEL_CALIBRATE, calibrate);
 360                 if (!ret) {
 361                         lttng_kernel_use_old_abi = 0;
 362                         goto end;
 363                 }
 364                 lttng_kernel_use_old_abi = 1;
 365         }
 366         if (lttng_kernel_use_old_abi) {
 367                 struct lttng_kernel_old_calibrate old_calibrate;
 368
 369                 old_calibrate.type = calibrate->type;
 370                 ret = ioctl(fd, LTTNG_KERNEL_OLD_CALIBRATE, &old_calibrate);
 371                 if (ret) {
 372                         goto end;
 373                 }
 374                 calibrate->type = old_calibrate.type;
 375         } else {
 376                 ret = ioctl(fd, LTTNG_KERNEL_CALIBRATE, calibrate);
 377         }
 378
 379 end:
 380         return ret;
 381 }
 382
 383
 384 int kernctl_buffer_flush(int fd)
 385 {
 386         return ioctl(fd, RING_BUFFER_FLUSH);
 387 }
 388
 389
 390 /* Buffer operations */
 391
 392 /* For mmap mode, readable without "get" operation */
 393
 394 /* returns the length to mmap. */
 395 int kernctl_get_mmap_len(int fd, unsigned long *len)
 396 {
 397         return ioctl(fd, RING_BUFFER_GET_MMAP_LEN, len);
 398 }
 399
 400 /* returns the maximum size for sub-buffers. */
 401 int kernctl_get_max_subbuf_size(int fd, unsigned long *len)
 402 {
 403         return ioctl(fd, RING_BUFFER_GET_MAX_SUBBUF_SIZE, len);
 404 }
 405
 406 /*
 407  * For mmap mode, operate on the current packet (between get/put or
 408  * get_next/put_next).
 409  */
 410
 411 /* returns the offset of the subbuffer belonging to the mmap reader. */
 412 int kernctl_get_mmap_read_offset(int fd, unsigned long *off)
 413 {
 414         return ioctl(fd, RING_BUFFER_GET_MMAP_READ_OFFSET, off);
 415 }
 416
 417 /* returns the size of the current sub-buffer, without padding (for mmap). */
 418 int kernctl_get_subbuf_size(int fd, unsigned long *len)
 419 {
 420         return ioctl(fd, RING_BUFFER_GET_SUBBUF_SIZE, len);
 421 }
 422
 423 /* returns the size of the current sub-buffer, without padding (for mmap). */
 424 int kernctl_get_padded_subbuf_size(int fd, unsigned long *len)
 425 {
 426         return ioctl(fd, RING_BUFFER_GET_PADDED_SUBBUF_SIZE, len);
 427 }
 428
 429 /* Get exclusive read access to the next sub-buffer that can be read. */
 430 int kernctl_get_next_subbuf(int fd)
 431 {
 432         return ioctl(fd, RING_BUFFER_GET_NEXT_SUBBUF);
 433 }
 434
 435
 436 /* Release exclusive sub-buffer access, move consumer forward. */
 437 int kernctl_put_next_subbuf(int fd)
 438 {
 439         return ioctl(fd, RING_BUFFER_PUT_NEXT_SUBBUF);
 440 }
 441
 442 /* snapshot */
 443
 444 /* Get a snapshot of the current ring buffer producer and consumer positions */
 445 int kernctl_snapshot(int fd)
 446 {
 447         return ioctl(fd, RING_BUFFER_SNAPSHOT);
 448 }
 449
 450 /* Get the consumer position (iteration start) */
 451 int kernctl_snapshot_get_consumed(int fd, unsigned long *pos)
 452 {
 453         return ioctl(fd, RING_BUFFER_SNAPSHOT_GET_CONSUMED, pos);
 454 }
 455
 456 /* Get the producer position (iteration end) */
 457 int kernctl_snapshot_get_produced(int fd, unsigned long *pos)
 458 {
 459         return ioctl(fd, RING_BUFFER_SNAPSHOT_GET_PRODUCED, pos);
 460 }
 461
 462 /* Get exclusive read access to the specified sub-buffer position */
 463 int kernctl_get_subbuf(int fd, unsigned long *len)
 464 {
 465         return ioctl(fd, RING_BUFFER_GET_SUBBUF, len);
 466 }
 467
 468 /* Release exclusive sub-buffer access */
 469 int kernctl_put_subbuf(int fd)
 470 {
 471         return ioctl(fd, RING_BUFFER_PUT_SUBBUF);
 472 }
 473
 474 /* Returns the timestamp begin of the current sub-buffer. */
 475 int kernctl_get_timestamp_begin(int fd, uint64_t *timestamp_begin)
 476 {
 477         return ioctl(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN, timestamp_begin);
 478 }
 479
 480 /* Returns the timestamp end of the current sub-buffer. */
 481 int kernctl_get_timestamp_end(int fd, uint64_t *timestamp_end)
 482 {
 483         return ioctl(fd, LTTNG_RING_BUFFER_GET_TIMESTAMP_END, timestamp_end);
 484 }
 485
 486 /* Returns the number of discarded events in the current sub-buffer. */
 487 int kernctl_get_events_discarded(int fd, uint64_t *events_discarded)
 488 {
 489         return ioctl(fd, LTTNG_RING_BUFFER_GET_EVENTS_DISCARDED, events_discarded);
 490 }
 491
 492 /* Returns the content size in the current sub-buffer. */
 493 int kernctl_get_content_size(int fd, uint64_t *content_size)
 494 {
 495         return ioctl(fd, LTTNG_RING_BUFFER_GET_CONTENT_SIZE, content_size);
 496 }
 497
 498 /* Returns the packet size in the current sub-buffer. */
 499 int kernctl_get_packet_size(int fd, uint64_t *packet_size)
 500 {
 501         return ioctl(fd, LTTNG_RING_BUFFER_GET_PACKET_SIZE, packet_size);
 502 }
 503
 504 /* Returns the stream id of the current sub-buffer. */
 505 int kernctl_get_stream_id(int fd, uint64_t *stream_id)
 506 {
 507         return ioctl(fd, LTTNG_RING_BUFFER_GET_STREAM_ID, stream_id);
 508 }
 509
 510 /* Returns the current timestamp. */
 511 int kernctl_get_current_timestamp(int fd, uint64_t *ts)
 512 {
 513         return ioctl(fd, LTTNG_RING_BUFFER_GET_CURRENT_TIMESTAMP, ts);
 514 }