secondary.c revision 211877
1/*- 2 * Copyright (c) 2009-2010 The FreeBSD Foundation 3 * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org> 4 * All rights reserved. 5 * 6 * This software was developed by Pawel Jakub Dawidek under sponsorship from 7 * the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31#include <sys/cdefs.h> 32__FBSDID("$FreeBSD: head/sbin/hastd/secondary.c 211877 2010-08-27 14:01:28Z pjd $"); 33 34#include <sys/param.h> 35#include <sys/time.h> 36#include <sys/bio.h> 37#include <sys/disk.h> 38#include <sys/stat.h> 39 40#include <assert.h> 41#include <err.h> 42#include <errno.h> 43#include <fcntl.h> 44#include <libgeom.h> 45#include <pthread.h> 46#include <stdint.h> 47#include <stdio.h> 48#include <string.h> 49#include <sysexits.h> 50#include <unistd.h> 51 52#include <activemap.h> 53#include <nv.h> 54#include <pjdlog.h> 55 56#include "control.h" 57#include "hast.h" 58#include "hast_proto.h" 59#include "hastd.h" 60#include "metadata.h" 61#include "proto.h" 62#include "subr.h" 63#include "synch.h" 64 65struct hio { 66 uint64_t hio_seq; 67 int hio_error; 68 struct nv *hio_nv; 69 void *hio_data; 70 uint8_t hio_cmd; 71 uint64_t hio_offset; 72 uint64_t hio_length; 73 TAILQ_ENTRY(hio) hio_next; 74}; 75 76/* 77 * Free list holds unused structures. When free list is empty, we have to wait 78 * until some in-progress requests are freed. 79 */ 80static TAILQ_HEAD(, hio) hio_free_list; 81static pthread_mutex_t hio_free_list_lock; 82static pthread_cond_t hio_free_list_cond; 83/* 84 * Disk thread (the one that do I/O requests) takes requests from this list. 85 */ 86static TAILQ_HEAD(, hio) hio_disk_list; 87static pthread_mutex_t hio_disk_list_lock; 88static pthread_cond_t hio_disk_list_cond; 89/* 90 * There is one recv list for every component, although local components don't 91 * use recv lists as local requests are done synchronously. 92 */ 93static TAILQ_HEAD(, hio) hio_send_list; 94static pthread_mutex_t hio_send_list_lock; 95static pthread_cond_t hio_send_list_cond; 96 97/* 98 * Maximum number of outstanding I/O requests. 99 */ 100#define HAST_HIO_MAX 256 101 102static void *recv_thread(void *arg); 103static void *disk_thread(void *arg); 104static void *send_thread(void *arg); 105 106#define QUEUE_INSERT(name, hio) do { \ 107 bool _wakeup; \ 108 \ 109 mtx_lock(&hio_##name##_list_lock); \ 110 _wakeup = TAILQ_EMPTY(&hio_##name##_list); \ 111 TAILQ_INSERT_TAIL(&hio_##name##_list, (hio), hio_next); \ 112 mtx_unlock(&hio_##name##_list_lock); \ 113 if (_wakeup) \ 114 cv_signal(&hio_##name##_list_cond); \ 115} while (0) 116#define QUEUE_TAKE(name, hio) do { \ 117 mtx_lock(&hio_##name##_list_lock); \ 118 while (((hio) = TAILQ_FIRST(&hio_##name##_list)) == NULL) { \ 119 cv_wait(&hio_##name##_list_cond, \ 120 &hio_##name##_list_lock); \ 121 } \ 122 TAILQ_REMOVE(&hio_##name##_list, (hio), hio_next); \ 123 mtx_unlock(&hio_##name##_list_lock); \ 124} while (0) 125 126static void 127init_environment(void) 128{ 129 struct hio *hio; 130 unsigned int ii; 131 132 /* 133 * Initialize lists, their locks and theirs condition variables. 134 */ 135 TAILQ_INIT(&hio_free_list); 136 mtx_init(&hio_free_list_lock); 137 cv_init(&hio_free_list_cond); 138 TAILQ_INIT(&hio_disk_list); 139 mtx_init(&hio_disk_list_lock); 140 cv_init(&hio_disk_list_cond); 141 TAILQ_INIT(&hio_send_list); 142 mtx_init(&hio_send_list_lock); 143 cv_init(&hio_send_list_cond); 144 145 /* 146 * Allocate requests pool and initialize requests. 147 */ 148 for (ii = 0; ii < HAST_HIO_MAX; ii++) { 149 hio = malloc(sizeof(*hio)); 150 if (hio == NULL) { 151 pjdlog_exitx(EX_TEMPFAIL, 152 "Unable to allocate memory (%zu bytes) for hio request.", 153 sizeof(*hio)); 154 } 155 hio->hio_error = 0; 156 hio->hio_data = malloc(MAXPHYS); 157 if (hio->hio_data == NULL) { 158 pjdlog_exitx(EX_TEMPFAIL, 159 "Unable to allocate memory (%zu bytes) for gctl_data.", 160 (size_t)MAXPHYS); 161 } 162 TAILQ_INSERT_HEAD(&hio_free_list, hio, hio_next); 163 } 164} 165 166static void 167init_local(struct hast_resource *res) 168{ 169 170 if (metadata_read(res, true) < 0) 171 exit(EX_NOINPUT); 172} 173 174static void 175init_remote(struct hast_resource *res, struct nv *nvin) 176{ 177 uint64_t resuid; 178 struct nv *nvout; 179 unsigned char *map; 180 size_t mapsize; 181 182 map = NULL; 183 mapsize = 0; 184 nvout = nv_alloc(); 185 nv_add_int64(nvout, (int64_t)res->hr_datasize, "datasize"); 186 nv_add_int32(nvout, (int32_t)res->hr_extentsize, "extentsize"); 187 resuid = nv_get_uint64(nvin, "resuid"); 188 res->hr_primary_localcnt = nv_get_uint64(nvin, "localcnt"); 189 res->hr_primary_remotecnt = nv_get_uint64(nvin, "remotecnt"); 190 nv_add_uint64(nvout, res->hr_secondary_localcnt, "localcnt"); 191 nv_add_uint64(nvout, res->hr_secondary_remotecnt, "remotecnt"); 192 mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize - 193 METADATA_SIZE, res->hr_extentsize, res->hr_local_sectorsize); 194 map = malloc(mapsize); 195 if (map == NULL) { 196 pjdlog_exitx(EX_TEMPFAIL, 197 "Unable to allocate memory (%zu bytes) for activemap.", 198 mapsize); 199 } 200 nv_add_uint32(nvout, (uint32_t)mapsize, "mapsize"); 201 /* 202 * When we work as primary and secondary is missing we will increase 203 * localcnt in our metadata. When secondary is connected and synced 204 * we make localcnt be equal to remotecnt, which means nodes are more 205 * or less in sync. 206 * Split-brain condition is when both nodes are not able to communicate 207 * and are both configured as primary nodes. In turn, they can both 208 * make incompatible changes to the data and we have to detect that. 209 * Under split-brain condition we will increase our localcnt on first 210 * write and remote node will increase its localcnt on first write. 211 * When we connect we can see that primary's localcnt is greater than 212 * our remotecnt (primary was modified while we weren't watching) and 213 * our localcnt is greater than primary's remotecnt (we were modified 214 * while primary wasn't watching). 215 * There are many possible combinations which are all gathered below. 216 * Don't pay too much attention to exact numbers, the more important 217 * is to compare them. We compare secondary's local with primary's 218 * remote and secondary's remote with primary's local. 219 * Note that every case where primary's localcnt is smaller than 220 * secondary's remotecnt and where secondary's localcnt is smaller than 221 * primary's remotecnt should be impossible in practise. We will perform 222 * full synchronization then. Those cases are marked with an asterisk. 223 * Regular synchronization means that only extents marked as dirty are 224 * synchronized (regular synchronization). 225 * 226 * SECONDARY METADATA PRIMARY METADATA 227 * local=3 remote=3 local=2 remote=2* ?! Full sync from secondary. 228 * local=3 remote=3 local=2 remote=3* ?! Full sync from primary. 229 * local=3 remote=3 local=2 remote=4* ?! Full sync from primary. 230 * local=3 remote=3 local=3 remote=2 Primary is out-of-date, 231 * regular sync from secondary. 232 * local=3 remote=3 local=3 remote=3 Regular sync just in case. 233 * local=3 remote=3 local=3 remote=4* ?! Full sync from primary. 234 * local=3 remote=3 local=4 remote=2 Split-brain condition. 235 * local=3 remote=3 local=4 remote=3 Secondary out-of-date, 236 * regular sync from primary. 237 * local=3 remote=3 local=4 remote=4* ?! Full sync from primary. 238 */ 239 if (res->hr_resuid == 0) { 240 /* 241 * Provider is used for the first time. Initialize everything. 242 */ 243 assert(res->hr_secondary_localcnt == 0); 244 res->hr_resuid = resuid; 245 if (metadata_write(res) < 0) 246 exit(EX_NOINPUT); 247 memset(map, 0xff, mapsize); 248 nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc"); 249 } else if ( 250 /* Is primary is out-of-date? */ 251 (res->hr_secondary_localcnt > res->hr_primary_remotecnt && 252 res->hr_secondary_remotecnt == res->hr_primary_localcnt) || 253 /* Node are more or less in sync? */ 254 (res->hr_secondary_localcnt == res->hr_primary_remotecnt && 255 res->hr_secondary_remotecnt == res->hr_primary_localcnt) || 256 /* Is secondary is out-of-date? */ 257 (res->hr_secondary_localcnt == res->hr_primary_remotecnt && 258 res->hr_secondary_remotecnt < res->hr_primary_localcnt)) { 259 /* 260 * Nodes are more or less in sync or one of the nodes is 261 * out-of-date. 262 * It doesn't matter at this point which one, we just have to 263 * send out local bitmap to the remote node. 264 */ 265 if (pread(res->hr_localfd, map, mapsize, METADATA_SIZE) != 266 (ssize_t)mapsize) { 267 pjdlog_exit(LOG_ERR, "Unable to read activemap"); 268 } 269 if (res->hr_secondary_localcnt > res->hr_primary_remotecnt && 270 res->hr_secondary_remotecnt == res->hr_primary_localcnt) { 271 /* Primary is out-of-date, sync from secondary. */ 272 nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc"); 273 } else { 274 /* 275 * Secondary is out-of-date or counts match. 276 * Sync from primary. 277 */ 278 nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc"); 279 } 280 } else if (res->hr_secondary_localcnt > res->hr_primary_remotecnt && 281 res->hr_primary_localcnt > res->hr_secondary_remotecnt) { 282 /* 283 * Not good, we have split-brain condition. 284 */ 285 pjdlog_error("Split-brain detected, exiting."); 286 nv_add_string(nvout, "Split-brain condition!", "errmsg"); 287 free(map); 288 map = NULL; 289 mapsize = 0; 290 } else /* if (res->hr_secondary_localcnt < res->hr_primary_remotecnt || 291 res->hr_primary_localcnt < res->hr_secondary_remotecnt) */ { 292 /* 293 * This should never happen in practise, but we will perform 294 * full synchronization. 295 */ 296 assert(res->hr_secondary_localcnt < res->hr_primary_remotecnt || 297 res->hr_primary_localcnt < res->hr_secondary_remotecnt); 298 mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize - 299 METADATA_SIZE, res->hr_extentsize, 300 res->hr_local_sectorsize); 301 memset(map, 0xff, mapsize); 302 if (res->hr_secondary_localcnt > res->hr_primary_remotecnt) { 303 /* In this one of five cases sync from secondary. */ 304 nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc"); 305 } else { 306 /* For the rest four cases sync from primary. */ 307 nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc"); 308 } 309 pjdlog_warning("This should never happen, asking for full synchronization (primary(local=%ju, remote=%ju), secondary(local=%ju, remote=%ju)).", 310 (uintmax_t)res->hr_primary_localcnt, 311 (uintmax_t)res->hr_primary_remotecnt, 312 (uintmax_t)res->hr_secondary_localcnt, 313 (uintmax_t)res->hr_secondary_remotecnt); 314 } 315 if (hast_proto_send(res, res->hr_remotein, nvout, map, mapsize) < 0) { 316 pjdlog_errno(LOG_WARNING, "Unable to send activemap to %s", 317 res->hr_remoteaddr); 318 nv_free(nvout); 319 exit(EX_TEMPFAIL); 320 } 321 nv_free(nvout); 322 if (res->hr_secondary_localcnt > res->hr_primary_remotecnt && 323 res->hr_primary_localcnt > res->hr_secondary_remotecnt) { 324 /* Exit on split-brain. */ 325 exit(EX_CONFIG); 326 } 327} 328 329void 330hastd_secondary(struct hast_resource *res, struct nv *nvin) 331{ 332 pthread_t td; 333 pid_t pid; 334 int error; 335 336 /* 337 * Create communication channel between parent and child. 338 */ 339 if (proto_client("socketpair://", &res->hr_ctrl) < 0) { 340 KEEP_ERRNO((void)pidfile_remove(pfh)); 341 pjdlog_exit(EX_OSERR, 342 "Unable to create control sockets between parent and child"); 343 } 344 345 pid = fork(); 346 if (pid < 0) { 347 KEEP_ERRNO((void)pidfile_remove(pfh)); 348 pjdlog_exit(EX_OSERR, "Unable to fork"); 349 } 350 351 if (pid > 0) { 352 /* This is parent. */ 353 proto_close(res->hr_remotein); 354 res->hr_remotein = NULL; 355 proto_close(res->hr_remoteout); 356 res->hr_remoteout = NULL; 357 res->hr_workerpid = pid; 358 return; 359 } 360 (void)pidfile_close(pfh); 361 362 setproctitle("%s (secondary)", res->hr_name); 363 364 signal(SIGHUP, SIG_DFL); 365 signal(SIGCHLD, SIG_DFL); 366 367 /* Error in setting timeout is not critical, but why should it fail? */ 368 if (proto_timeout(res->hr_remotein, 0) < 0) 369 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout"); 370 if (proto_timeout(res->hr_remoteout, res->hr_timeout) < 0) 371 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout"); 372 373 init_local(res); 374 init_remote(res, nvin); 375 init_environment(); 376 377 error = pthread_create(&td, NULL, recv_thread, res); 378 assert(error == 0); 379 error = pthread_create(&td, NULL, disk_thread, res); 380 assert(error == 0); 381 error = pthread_create(&td, NULL, send_thread, res); 382 assert(error == 0); 383 (void)ctrl_thread(res); 384} 385 386static void 387reqlog(int loglevel, int debuglevel, int error, struct hio *hio, const char *fmt, ...) 388{ 389 char msg[1024]; 390 va_list ap; 391 int len; 392 393 va_start(ap, fmt); 394 len = vsnprintf(msg, sizeof(msg), fmt, ap); 395 va_end(ap); 396 if ((size_t)len < sizeof(msg)) { 397 switch (hio->hio_cmd) { 398 case HIO_READ: 399 (void)snprintf(msg + len, sizeof(msg) - len, 400 "READ(%ju, %ju).", (uintmax_t)hio->hio_offset, 401 (uintmax_t)hio->hio_length); 402 break; 403 case HIO_DELETE: 404 (void)snprintf(msg + len, sizeof(msg) - len, 405 "DELETE(%ju, %ju).", (uintmax_t)hio->hio_offset, 406 (uintmax_t)hio->hio_length); 407 break; 408 case HIO_FLUSH: 409 (void)snprintf(msg + len, sizeof(msg) - len, "FLUSH."); 410 break; 411 case HIO_WRITE: 412 (void)snprintf(msg + len, sizeof(msg) - len, 413 "WRITE(%ju, %ju).", (uintmax_t)hio->hio_offset, 414 (uintmax_t)hio->hio_length); 415 break; 416 default: 417 (void)snprintf(msg + len, sizeof(msg) - len, 418 "UNKNOWN(%u).", (unsigned int)hio->hio_cmd); 419 break; 420 } 421 } 422 pjdlog_common(loglevel, debuglevel, error, "%s", msg); 423} 424 425static int 426requnpack(struct hast_resource *res, struct hio *hio) 427{ 428 429 hio->hio_cmd = nv_get_uint8(hio->hio_nv, "cmd"); 430 if (hio->hio_cmd == 0) { 431 pjdlog_error("Header contains no 'cmd' field."); 432 hio->hio_error = EINVAL; 433 goto end; 434 } 435 switch (hio->hio_cmd) { 436 case HIO_READ: 437 case HIO_WRITE: 438 case HIO_DELETE: 439 hio->hio_offset = nv_get_uint64(hio->hio_nv, "offset"); 440 if (nv_error(hio->hio_nv) != 0) { 441 pjdlog_error("Header is missing 'offset' field."); 442 hio->hio_error = EINVAL; 443 goto end; 444 } 445 hio->hio_length = nv_get_uint64(hio->hio_nv, "length"); 446 if (nv_error(hio->hio_nv) != 0) { 447 pjdlog_error("Header is missing 'length' field."); 448 hio->hio_error = EINVAL; 449 goto end; 450 } 451 if (hio->hio_length == 0) { 452 pjdlog_error("Data length is zero."); 453 hio->hio_error = EINVAL; 454 goto end; 455 } 456 if (hio->hio_length > MAXPHYS) { 457 pjdlog_error("Data length is too large (%ju > %ju).", 458 (uintmax_t)hio->hio_length, (uintmax_t)MAXPHYS); 459 hio->hio_error = EINVAL; 460 goto end; 461 } 462 if ((hio->hio_offset % res->hr_local_sectorsize) != 0) { 463 pjdlog_error("Offset %ju is not multiple of sector size.", 464 (uintmax_t)hio->hio_offset); 465 hio->hio_error = EINVAL; 466 goto end; 467 } 468 if ((hio->hio_length % res->hr_local_sectorsize) != 0) { 469 pjdlog_error("Length %ju is not multiple of sector size.", 470 (uintmax_t)hio->hio_length); 471 hio->hio_error = EINVAL; 472 goto end; 473 } 474 if (hio->hio_offset + hio->hio_length > 475 (uint64_t)res->hr_datasize) { 476 pjdlog_error("Data offset is too large (%ju > %ju).", 477 (uintmax_t)(hio->hio_offset + hio->hio_length), 478 (uintmax_t)res->hr_datasize); 479 hio->hio_error = EINVAL; 480 goto end; 481 } 482 break; 483 default: 484 pjdlog_error("Header contains invalid 'cmd' (%hhu).", 485 hio->hio_cmd); 486 hio->hio_error = EINVAL; 487 goto end; 488 } 489 hio->hio_error = 0; 490end: 491 return (hio->hio_error); 492} 493 494/* 495 * Thread receives requests from the primary node. 496 */ 497static void * 498recv_thread(void *arg) 499{ 500 struct hast_resource *res = arg; 501 struct hio *hio; 502 503 for (;;) { 504 pjdlog_debug(2, "recv: Taking free request."); 505 QUEUE_TAKE(free, hio); 506 pjdlog_debug(2, "recv: (%p) Got request.", hio); 507 if (hast_proto_recv_hdr(res->hr_remotein, &hio->hio_nv) < 0) { 508 pjdlog_exit(EX_TEMPFAIL, 509 "Unable to receive request header"); 510 } 511 if (requnpack(res, hio) != 0) { 512 pjdlog_debug(2, 513 "recv: (%p) Moving request to the send queue.", 514 hio); 515 QUEUE_INSERT(send, hio); 516 continue; 517 } 518 reqlog(LOG_DEBUG, 2, -1, hio, 519 "recv: (%p) Got request header: ", hio); 520 if (hio->hio_cmd == HIO_WRITE) { 521 if (hast_proto_recv_data(res, res->hr_remotein, 522 hio->hio_nv, hio->hio_data, MAXPHYS) < 0) { 523 pjdlog_exit(EX_TEMPFAIL, 524 "Unable to receive reply data"); 525 } 526 } 527 pjdlog_debug(2, "recv: (%p) Moving request to the disk queue.", 528 hio); 529 QUEUE_INSERT(disk, hio); 530 } 531 /* NOTREACHED */ 532 return (NULL); 533} 534 535/* 536 * Thread reads from or writes to local component and also handles DELETE and 537 * FLUSH requests. 538 */ 539static void * 540disk_thread(void *arg) 541{ 542 struct hast_resource *res = arg; 543 struct hio *hio; 544 ssize_t ret; 545 bool clear_activemap; 546 547 clear_activemap = true; 548 549 for (;;) { 550 pjdlog_debug(2, "disk: Taking request."); 551 QUEUE_TAKE(disk, hio); 552 while (clear_activemap) { 553 unsigned char *map; 554 size_t mapsize; 555 556 /* 557 * When first request is received, it means that primary 558 * already received our activemap, merged it and stored 559 * locally. We can now safely clear our activemap. 560 */ 561 mapsize = 562 activemap_calc_ondisk_size(res->hr_local_mediasize - 563 METADATA_SIZE, res->hr_extentsize, 564 res->hr_local_sectorsize); 565 map = calloc(1, mapsize); 566 if (map == NULL) { 567 pjdlog_warning("Unable to allocate memory to clear local activemap."); 568 break; 569 } 570 if (pwrite(res->hr_localfd, map, mapsize, 571 METADATA_SIZE) != (ssize_t)mapsize) { 572 pjdlog_errno(LOG_WARNING, 573 "Unable to store cleared activemap"); 574 free(map); 575 break; 576 } 577 free(map); 578 clear_activemap = false; 579 pjdlog_debug(1, "Local activemap cleared."); 580 } 581 reqlog(LOG_DEBUG, 2, -1, hio, "disk: (%p) Got request: ", hio); 582 /* Handle the actual request. */ 583 switch (hio->hio_cmd) { 584 case HIO_READ: 585 ret = pread(res->hr_localfd, hio->hio_data, 586 hio->hio_length, 587 hio->hio_offset + res->hr_localoff); 588 if (ret < 0) 589 hio->hio_error = errno; 590 else if (ret != (int64_t)hio->hio_length) 591 hio->hio_error = EIO; 592 else 593 hio->hio_error = 0; 594 break; 595 case HIO_WRITE: 596 ret = pwrite(res->hr_localfd, hio->hio_data, 597 hio->hio_length, 598 hio->hio_offset + res->hr_localoff); 599 if (ret < 0) 600 hio->hio_error = errno; 601 else if (ret != (int64_t)hio->hio_length) 602 hio->hio_error = EIO; 603 else 604 hio->hio_error = 0; 605 break; 606 case HIO_DELETE: 607 ret = g_delete(res->hr_localfd, 608 hio->hio_offset + res->hr_localoff, 609 hio->hio_length); 610 if (ret < 0) 611 hio->hio_error = errno; 612 else 613 hio->hio_error = 0; 614 break; 615 case HIO_FLUSH: 616 ret = g_flush(res->hr_localfd); 617 if (ret < 0) 618 hio->hio_error = errno; 619 else 620 hio->hio_error = 0; 621 break; 622 } 623 if (hio->hio_error != 0) { 624 reqlog(LOG_ERR, 0, hio->hio_error, hio, 625 "Request failed: "); 626 } 627 pjdlog_debug(2, "disk: (%p) Moving request to the send queue.", 628 hio); 629 QUEUE_INSERT(send, hio); 630 } 631 /* NOTREACHED */ 632 return (NULL); 633} 634 635/* 636 * Thread sends requests back to primary node. 637 */ 638static void * 639send_thread(void *arg) 640{ 641 struct hast_resource *res = arg; 642 struct nv *nvout; 643 struct hio *hio; 644 void *data; 645 size_t length; 646 647 for (;;) { 648 pjdlog_debug(2, "send: Taking request."); 649 QUEUE_TAKE(send, hio); 650 reqlog(LOG_DEBUG, 2, -1, hio, "send: (%p) Got request: ", hio); 651 nvout = nv_alloc(); 652 /* Copy sequence number. */ 653 nv_add_uint64(nvout, nv_get_uint64(hio->hio_nv, "seq"), "seq"); 654 switch (hio->hio_cmd) { 655 case HIO_READ: 656 if (hio->hio_error == 0) { 657 data = hio->hio_data; 658 length = hio->hio_length; 659 break; 660 } 661 /* 662 * We send no data in case of an error. 663 */ 664 /* FALLTHROUGH */ 665 case HIO_DELETE: 666 case HIO_FLUSH: 667 case HIO_WRITE: 668 data = NULL; 669 length = 0; 670 break; 671 default: 672 abort(); 673 break; 674 } 675 if (hio->hio_error != 0) 676 nv_add_int16(nvout, hio->hio_error, "error"); 677 if (hast_proto_send(res, res->hr_remoteout, nvout, data, 678 length) < 0) { 679 pjdlog_exit(EX_TEMPFAIL, "Unable to send reply."); 680 } 681 nv_free(nvout); 682 pjdlog_debug(2, "send: (%p) Moving request to the free queue.", 683 hio); 684 nv_free(hio->hio_nv); 685 hio->hio_error = 0; 686 QUEUE_INSERT(free, hio); 687 } 688 /* NOTREACHED */ 689 return (NULL); 690} 691