sbin/hastd/primary.c

   1 /*-
   2  * Copyright (c) 2009 The FreeBSD Foundation
   3  * Copyright (c) 2010-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
   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("$FreeBSD$");
  33
  34 #include <sys/types.h>
  35 #include <sys/time.h>
  36 #include <sys/bio.h>
  37 #include <sys/disk.h>
  38 #include <sys/refcount.h>
  39 #include <sys/stat.h>
  40
  41 #include <geom/gate/g_gate.h>
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <fcntl.h>
  46 #include <libgeom.h>
  47 #include <pthread.h>
  48 #include <signal.h>
  49 #include <stdint.h>
  50 #include <stdio.h>
  51 #include <string.h>
  52 #include <sysexits.h>
  53 #include <unistd.h>
  54
  55 #include <activemap.h>
  56 #include <nv.h>
  57 #include <rangelock.h>
  58
  59 #include "control.h"
  60 #include "event.h"
  61 #include "hast.h"
  62 #include "hast_proto.h"
  63 #include "hastd.h"
  64 #include "hooks.h"
  65 #include "metadata.h"
  66 #include "proto.h"
  67 #include "pjdlog.h"
  68 #include "subr.h"
  69 #include "synch.h"
  70
  71 /* The is only one remote component for now. */
  72 #define ISREMOTE(no)    ((no) == 1)
  73
  74 struct hio {
  75         /*
  76          * Number of components we are still waiting for.
  77          * When this field goes to 0, we can send the request back to the
  78          * kernel. Each component has to decrease this counter by one
  79          * even on failure.
  80          */
  81         unsigned int             hio_countdown;
  82         /*
  83          * Each component has a place to store its own error.
  84          * Once the request is handled by all components we can decide if the
  85          * request overall is successful or not.
  86          */
  87         int                     *hio_errors;
  88         /*
  89          * Structure used to communicate with GEOM Gate class.
  90          */
  91         struct g_gate_ctl_io     hio_ggio;
  92         /*
  93          * Request was already confirmed to GEOM Gate.
  94          */
  95         bool                     hio_done;
  96         /*
  97          * Remember replication from the time the request was initiated,
  98          * so we won't get confused when replication changes on reload.
  99          */
 100         int                      hio_replication;
 101         TAILQ_ENTRY(hio)        *hio_next;
 102 };
 103 #define hio_free_next   hio_next[0]
 104 #define hio_done_next   hio_next[0]
 105
 106 /*
 107  * Free list holds unused structures. When free list is empty, we have to wait
 108  * until some in-progress requests are freed.
 109  */
 110 static TAILQ_HEAD(, hio) hio_free_list;
 111 static pthread_mutex_t hio_free_list_lock;
 112 static pthread_cond_t hio_free_list_cond;
 113 /*
 114  * There is one send list for every component. One requests is placed on all
 115  * send lists - each component gets the same request, but each component is
 116  * responsible for managing his own send list.
 117  */
 118 static TAILQ_HEAD(, hio) *hio_send_list;
 119 static pthread_mutex_t *hio_send_list_lock;
 120 static pthread_cond_t *hio_send_list_cond;
 121 /*
 122  * There is one recv list for every component, although local components don't
 123  * use recv lists as local requests are done synchronously.
 124  */
 125 static TAILQ_HEAD(, hio) *hio_recv_list;
 126 static pthread_mutex_t *hio_recv_list_lock;
 127 static pthread_cond_t *hio_recv_list_cond;
 128 /*
 129  * Request is placed on done list by the slowest component (the one that
 130  * decreased hio_countdown from 1 to 0).
 131  */
 132 static TAILQ_HEAD(, hio) hio_done_list;
 133 static pthread_mutex_t hio_done_list_lock;
 134 static pthread_cond_t hio_done_list_cond;
 135 /*
 136  * Structure below are for interaction with sync thread.
 137  */
 138 static bool sync_inprogress;
 139 static pthread_mutex_t sync_lock;
 140 static pthread_cond_t sync_cond;
 141 /*
 142  * The lock below allows to synchornize access to remote connections.
 143  */
 144 static pthread_rwlock_t *hio_remote_lock;
 145
 146 /*
 147  * Lock to synchronize metadata updates. Also synchronize access to
 148  * hr_primary_localcnt and hr_primary_remotecnt fields.
 149  */
 150 static pthread_mutex_t metadata_lock;
 151
 152 /*
 153  * Maximum number of outstanding I/O requests.
 154  */
 155 #define HAST_HIO_MAX    256
 156 /*
 157  * Number of components. At this point there are only two components: local
 158  * and remote, but in the future it might be possible to use multiple local
 159  * and remote components.
 160  */
 161 #define HAST_NCOMPONENTS        2
 162
 163 #define ISCONNECTED(res, no)    \
 164         ((res)->hr_remotein != NULL && (res)->hr_remoteout != NULL)
 165
 166 #define QUEUE_INSERT1(hio, name, ncomp) do {                            \
 167         bool _wakeup;                                                   \
 168                                                                         \
 169         mtx_lock(&hio_##name##_list_lock[(ncomp)]);                     \
 170         _wakeup = TAILQ_EMPTY(&hio_##name##_list[(ncomp)]);             \
 171         TAILQ_INSERT_TAIL(&hio_##name##_list[(ncomp)], (hio),           \
 172             hio_next[(ncomp)]);                                         \
 173         mtx_unlock(&hio_##name##_list_lock[ncomp]);                     \
 174         if (_wakeup)                                                    \
 175                 cv_signal(&hio_##name##_list_cond[(ncomp)]);            \
 176 } while (0)
 177 #define QUEUE_INSERT2(hio, name)        do {                            \
 178         bool _wakeup;                                                   \
 179                                                                         \
 180         mtx_lock(&hio_##name##_list_lock);                              \
 181         _wakeup = TAILQ_EMPTY(&hio_##name##_list);                      \
 182         TAILQ_INSERT_TAIL(&hio_##name##_list, (hio), hio_##name##_next);\
 183         mtx_unlock(&hio_##name##_list_lock);                            \
 184         if (_wakeup)                                                    \
 185                 cv_signal(&hio_##name##_list_cond);                     \
 186 } while (0)
 187 #define QUEUE_TAKE1(hio, name, ncomp, timeout)  do {                    \
 188         bool _last;                                                     \
 189                                                                         \
 190         mtx_lock(&hio_##name##_list_lock[(ncomp)]);                     \
 191         _last = false;                                                  \
 192         while (((hio) = TAILQ_FIRST(&hio_##name##_list[(ncomp)])) == NULL && !_last) { \
 193                 cv_timedwait(&hio_##name##_list_cond[(ncomp)],          \
 194                     &hio_##name##_list_lock[(ncomp)], (timeout));       \
 195                 if ((timeout) != 0)                                     \
 196                         _last = true;                                   \
 197         }                                                               \
 198         if (hio != NULL) {                                              \
 199                 TAILQ_REMOVE(&hio_##name##_list[(ncomp)], (hio),        \
 200                     hio_next[(ncomp)]);                                 \
 201         }                                                               \
 202         mtx_unlock(&hio_##name##_list_lock[(ncomp)]);                   \
 203 } while (0)
 204 #define QUEUE_TAKE2(hio, name)  do {                                    \
 205         mtx_lock(&hio_##name##_list_lock);                              \
 206         while (((hio) = TAILQ_FIRST(&hio_##name##_list)) == NULL) {     \
 207                 cv_wait(&hio_##name##_list_cond,                        \
 208                     &hio_##name##_list_lock);                           \
 209         }                                                               \
 210         TAILQ_REMOVE(&hio_##name##_list, (hio), hio_##name##_next);     \
 211         mtx_unlock(&hio_##name##_list_lock);                            \
 212 } while (0)
 213
 214 #define SYNCREQ(hio)            do {                                    \
 215         (hio)->hio_ggio.gctl_unit = -1;                                 \
 216         (hio)->hio_ggio.gctl_seq = 1;                                   \
 217 } while (0)
 218 #define ISSYNCREQ(hio)          ((hio)->hio_ggio.gctl_unit == -1)
 219 #define SYNCREQDONE(hio)        do { (hio)->hio_ggio.gctl_unit = -2; } while (0)
 220 #define ISSYNCREQDONE(hio)      ((hio)->hio_ggio.gctl_unit == -2)
 221
 222 static struct hast_resource *gres;
 223
 224 static pthread_mutex_t range_lock;
 225 static struct rangelocks *range_regular;
 226 static bool range_regular_wait;
 227 static pthread_cond_t range_regular_cond;
 228 static struct rangelocks *range_sync;
 229 static bool range_sync_wait;
 230 static pthread_cond_t range_sync_cond;
 231 static bool fullystarted;
 232
 233 static void *ggate_recv_thread(void *arg);
 234 static void *local_send_thread(void *arg);
 235 static void *remote_send_thread(void *arg);
 236 static void *remote_recv_thread(void *arg);
 237 static void *ggate_send_thread(void *arg);
 238 static void *sync_thread(void *arg);
 239 static void *guard_thread(void *arg);
 240
 241 static void
 242 cleanup(struct hast_resource *res)
 243 {
 244         int rerrno;
 245
 246         /* Remember errno. */
 247         rerrno = errno;
 248
 249         /* Destroy ggate provider if we created one. */
 250         if (res->hr_ggateunit >= 0) {
 251                 struct g_gate_ctl_destroy ggiod;
 252
 253                 bzero(&ggiod, sizeof(ggiod));
 254                 ggiod.gctl_version = G_GATE_VERSION;
 255                 ggiod.gctl_unit = res->hr_ggateunit;
 256                 ggiod.gctl_force = 1;
 257                 if (ioctl(res->hr_ggatefd, G_GATE_CMD_DESTROY, &ggiod) == -1) {
 258                         pjdlog_errno(LOG_WARNING,
 259                             "Unable to destroy hast/%s device",
 260                             res->hr_provname);
 261                 }
 262                 res->hr_ggateunit = -1;
 263         }
 264
 265         /* Restore errno. */
 266         errno = rerrno;
 267 }
 268
 269 static __dead2 void
 270 primary_exit(int exitcode, const char *fmt, ...)
 271 {
 272         va_list ap;
 273
 274         PJDLOG_ASSERT(exitcode != EX_OK);
 275         va_start(ap, fmt);
 276         pjdlogv_errno(LOG_ERR, fmt, ap);
 277         va_end(ap);
 278         cleanup(gres);
 279         exit(exitcode);
 280 }
 281
 282 static __dead2 void
 283 primary_exitx(int exitcode, const char *fmt, ...)
 284 {
 285         va_list ap;
 286
 287         va_start(ap, fmt);
 288         pjdlogv(exitcode == EX_OK ? LOG_INFO : LOG_ERR, fmt, ap);
 289         va_end(ap);
 290         cleanup(gres);
 291         exit(exitcode);
 292 }
 293
 294 static int
 295 hast_activemap_flush(struct hast_resource *res)
 296 {
 297         const unsigned char *buf;
 298         size_t size;
 299
 300         buf = activemap_bitmap(res->hr_amp, &size);
 301         PJDLOG_ASSERT(buf != NULL);
 302         PJDLOG_ASSERT((size % res->hr_local_sectorsize) == 0);
 303         if (pwrite(res->hr_localfd, buf, size, METADATA_SIZE) !=
 304             (ssize_t)size) {
 305                 pjdlog_errno(LOG_ERR, "Unable to flush activemap to disk");
 306                 return (-1);
 307         }
 308         if (res->hr_metaflush == 1 && g_flush(res->hr_localfd) == -1) {
 309                 if (errno == EOPNOTSUPP) {
 310                         pjdlog_warning("The %s provider doesn't support flushing write cache. Disabling it.",
 311                             res->hr_localpath);
 312                         res->hr_metaflush = 0;
 313                 } else {
 314                         pjdlog_errno(LOG_ERR,
 315                             "Unable to flush disk cache on activemap update");
 316                         return (-1);
 317                 }
 318         }
 319         return (0);
 320 }
 321
 322 static bool
 323 real_remote(const struct hast_resource *res)
 324 {
 325
 326         return (strcmp(res->hr_remoteaddr, "none") != 0);
 327 }
 328
 329 static void
 330 init_environment(struct hast_resource *res __unused)
 331 {
 332         struct hio *hio;
 333         unsigned int ii, ncomps;
 334
 335         /*
 336          * In the future it might be per-resource value.
 337          */
 338         ncomps = HAST_NCOMPONENTS;
 339
 340         /*
 341          * Allocate memory needed by lists.
 342          */
 343         hio_send_list = malloc(sizeof(hio_send_list[0]) * ncomps);
 344         if (hio_send_list == NULL) {
 345                 primary_exitx(EX_TEMPFAIL,
 346                     "Unable to allocate %zu bytes of memory for send lists.",
 347                     sizeof(hio_send_list[0]) * ncomps);
 348         }
 349         hio_send_list_lock = malloc(sizeof(hio_send_list_lock[0]) * ncomps);
 350         if (hio_send_list_lock == NULL) {
 351                 primary_exitx(EX_TEMPFAIL,
 352                     "Unable to allocate %zu bytes of memory for send list locks.",
 353                     sizeof(hio_send_list_lock[0]) * ncomps);
 354         }
 355         hio_send_list_cond = malloc(sizeof(hio_send_list_cond[0]) * ncomps);
 356         if (hio_send_list_cond == NULL) {
 357                 primary_exitx(EX_TEMPFAIL,
 358                     "Unable to allocate %zu bytes of memory for send list condition variables.",
 359                     sizeof(hio_send_list_cond[0]) * ncomps);
 360         }
 361         hio_recv_list = malloc(sizeof(hio_recv_list[0]) * ncomps);
 362         if (hio_recv_list == NULL) {
 363                 primary_exitx(EX_TEMPFAIL,
 364                     "Unable to allocate %zu bytes of memory for recv lists.",
 365                     sizeof(hio_recv_list[0]) * ncomps);
 366         }
 367         hio_recv_list_lock = malloc(sizeof(hio_recv_list_lock[0]) * ncomps);
 368         if (hio_recv_list_lock == NULL) {
 369                 primary_exitx(EX_TEMPFAIL,
 370                     "Unable to allocate %zu bytes of memory for recv list locks.",
 371                     sizeof(hio_recv_list_lock[0]) * ncomps);
 372         }
 373         hio_recv_list_cond = malloc(sizeof(hio_recv_list_cond[0]) * ncomps);
 374         if (hio_recv_list_cond == NULL) {
 375                 primary_exitx(EX_TEMPFAIL,
 376                     "Unable to allocate %zu bytes of memory for recv list condition variables.",
 377                     sizeof(hio_recv_list_cond[0]) * ncomps);
 378         }
 379         hio_remote_lock = malloc(sizeof(hio_remote_lock[0]) * ncomps);
 380         if (hio_remote_lock == NULL) {
 381                 primary_exitx(EX_TEMPFAIL,
 382                     "Unable to allocate %zu bytes of memory for remote connections locks.",
 383                     sizeof(hio_remote_lock[0]) * ncomps);
 384         }
 385
 386         /*
 387          * Initialize lists, their locks and theirs condition variables.
 388          */
 389         TAILQ_INIT(&hio_free_list);
 390         mtx_init(&hio_free_list_lock);
 391         cv_init(&hio_free_list_cond);
 392         for (ii = 0; ii < HAST_NCOMPONENTS; ii++) {
 393                 TAILQ_INIT(&hio_send_list[ii]);
 394                 mtx_init(&hio_send_list_lock[ii]);
 395                 cv_init(&hio_send_list_cond[ii]);
 396                 TAILQ_INIT(&hio_recv_list[ii]);
 397                 mtx_init(&hio_recv_list_lock[ii]);
 398                 cv_init(&hio_recv_list_cond[ii]);
 399                 rw_init(&hio_remote_lock[ii]);
 400         }
 401         TAILQ_INIT(&hio_done_list);
 402         mtx_init(&hio_done_list_lock);
 403         cv_init(&hio_done_list_cond);
 404         mtx_init(&metadata_lock);
 405
 406         /*
 407          * Allocate requests pool and initialize requests.
 408          */
 409         for (ii = 0; ii < HAST_HIO_MAX; ii++) {
 410                 hio = malloc(sizeof(*hio));
 411                 if (hio == NULL) {
 412                         primary_exitx(EX_TEMPFAIL,
 413                             "Unable to allocate %zu bytes of memory for hio request.",
 414                             sizeof(*hio));
 415                 }
 416                 hio->hio_countdown = 0;
 417                 hio->hio_errors = malloc(sizeof(hio->hio_errors[0]) * ncomps);
 418                 if (hio->hio_errors == NULL) {
 419                         primary_exitx(EX_TEMPFAIL,
 420                             "Unable allocate %zu bytes of memory for hio errors.",
 421                             sizeof(hio->hio_errors[0]) * ncomps);
 422                 }
 423                 hio->hio_next = malloc(sizeof(hio->hio_next[0]) * ncomps);
 424                 if (hio->hio_next == NULL) {
 425                         primary_exitx(EX_TEMPFAIL,
 426                             "Unable allocate %zu bytes of memory for hio_next field.",
 427                             sizeof(hio->hio_next[0]) * ncomps);
 428                 }
 429                 hio->hio_ggio.gctl_version = G_GATE_VERSION;
 430                 hio->hio_ggio.gctl_data = malloc(MAXPHYS);
 431                 if (hio->hio_ggio.gctl_data == NULL) {
 432                         primary_exitx(EX_TEMPFAIL,
 433                             "Unable to allocate %zu bytes of memory for gctl_data.",
 434                             MAXPHYS);
 435                 }
 436                 hio->hio_ggio.gctl_length = MAXPHYS;
 437                 hio->hio_ggio.gctl_error = 0;
 438                 TAILQ_INSERT_HEAD(&hio_free_list, hio, hio_free_next);
 439         }
 440 }
 441
 442 static bool
 443 init_resuid(struct hast_resource *res)
 444 {
 445
 446         mtx_lock(&metadata_lock);
 447         if (res->hr_resuid != 0) {
 448                 mtx_unlock(&metadata_lock);
 449                 return (false);
 450         } else {
 451                 /* Initialize unique resource identifier. */
 452                 arc4random_buf(&res->hr_resuid, sizeof(res->hr_resuid));
 453                 mtx_unlock(&metadata_lock);
 454                 if (metadata_write(res) == -1)
 455                         exit(EX_NOINPUT);
 456                 return (true);
 457         }
 458 }
 459
 460 static void
 461 init_local(struct hast_resource *res)
 462 {
 463         unsigned char *buf;
 464         size_t mapsize;
 465
 466         if (metadata_read(res, true) == -1)
 467                 exit(EX_NOINPUT);
 468         mtx_init(&res->hr_amp_lock);
 469         if (activemap_init(&res->hr_amp, res->hr_datasize, res->hr_extentsize,
 470             res->hr_local_sectorsize, res->hr_keepdirty) == -1) {
 471                 primary_exit(EX_TEMPFAIL, "Unable to create activemap");
 472         }
 473         mtx_init(&range_lock);
 474         cv_init(&range_regular_cond);
 475         if (rangelock_init(&range_regular) == -1)
 476                 primary_exit(EX_TEMPFAIL, "Unable to create regular range lock");
 477         cv_init(&range_sync_cond);
 478         if (rangelock_init(&range_sync) == -1)
 479                 primary_exit(EX_TEMPFAIL, "Unable to create sync range lock");
 480         mapsize = activemap_ondisk_size(res->hr_amp);
 481         buf = calloc(1, mapsize);
 482         if (buf == NULL) {
 483                 primary_exitx(EX_TEMPFAIL,
 484                     "Unable to allocate buffer for activemap.");
 485         }
 486         if (pread(res->hr_localfd, buf, mapsize, METADATA_SIZE) !=
 487             (ssize_t)mapsize) {
 488                 primary_exit(EX_NOINPUT, "Unable to read activemap");
 489         }
 490         activemap_copyin(res->hr_amp, buf, mapsize);
 491         free(buf);
 492         if (res->hr_resuid != 0)
 493                 return;
 494         /*
 495          * We're using provider for the first time. Initialize local and remote
 496          * counters. We don't initialize resuid here, as we want to do it just
 497          * in time. The reason for this is that we want to inform secondary
 498          * that there were no writes yet, so there is no need to synchronize
 499          * anything.
 500          */
 501         res->hr_primary_localcnt = 0;
 502         res->hr_primary_remotecnt = 0;
 503         if (metadata_write(res) == -1)
 504                 exit(EX_NOINPUT);
 505 }
 506
 507 static int
 508 primary_connect(struct hast_resource *res, struct proto_conn **connp)
 509 {
 510         struct proto_conn *conn;
 511         int16_t val;
 512
 513         val = 1;
 514         if (proto_send(res->hr_conn, &val, sizeof(val)) == -1) {
 515                 primary_exit(EX_TEMPFAIL,
 516                     "Unable to send connection request to parent");
 517         }
 518         if (proto_recv(res->hr_conn, &val, sizeof(val)) == -1) {
 519                 primary_exit(EX_TEMPFAIL,
 520                     "Unable to receive reply to connection request from parent");
 521         }
 522         if (val != 0) {
 523                 errno = val;
 524                 pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
 525                     res->hr_remoteaddr);
 526                 return (-1);
 527         }
 528         if (proto_connection_recv(res->hr_conn, true, &conn) == -1) {
 529                 primary_exit(EX_TEMPFAIL,
 530                     "Unable to receive connection from parent");
 531         }
 532         if (proto_connect_wait(conn, res->hr_timeout) == -1) {
 533                 pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
 534                     res->hr_remoteaddr);
 535                 proto_close(conn);
 536                 return (-1);
 537         }
 538         /* Error in setting timeout is not critical, but why should it fail? */
 539         if (proto_timeout(conn, res->hr_timeout) == -1)
 540                 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
 541
 542         *connp = conn;
 543
 544         return (0);
 545 }
 546
 547 static int
 548 init_remote(struct hast_resource *res, struct proto_conn **inp,
 549     struct proto_conn **outp)
 550 {
 551         struct proto_conn *in, *out;
 552         struct nv *nvout, *nvin;
 553         const unsigned char *token;
 554         unsigned char *map;
 555         const char *errmsg;
 556         int32_t extentsize;
 557         int64_t datasize;
 558         uint32_t mapsize;
 559         size_t size;
 560         int error;
 561
 562         PJDLOG_ASSERT((inp == NULL && outp == NULL) || (inp != NULL && outp != NULL));
 563         PJDLOG_ASSERT(real_remote(res));
 564
 565         in = out = NULL;
 566         errmsg = NULL;
 567
 568         if (primary_connect(res, &out) == -1)
 569                 return (ECONNREFUSED);
 570
 571         error = ECONNABORTED;
 572
 573         /*
 574          * First handshake step.
 575          * Setup outgoing connection with remote node.
 576          */
 577         nvout = nv_alloc();
 578         nv_add_string(nvout, res->hr_name, "resource");
 579         if (nv_error(nvout) != 0) {
 580                 pjdlog_common(LOG_WARNING, 0, nv_error(nvout),
 581                     "Unable to allocate header for connection with %s",
 582                     res->hr_remoteaddr);
 583                 nv_free(nvout);
 584                 goto close;
 585         }
 586         if (hast_proto_send(res, out, nvout, NULL, 0) == -1) {
 587                 pjdlog_errno(LOG_WARNING,
 588                     "Unable to send handshake header to %s",
 589                     res->hr_remoteaddr);
 590                 nv_free(nvout);
 591                 goto close;
 592         }
 593         nv_free(nvout);
 594         if (hast_proto_recv_hdr(out, &nvin) == -1) {
 595                 pjdlog_errno(LOG_WARNING,
 596                     "Unable to receive handshake header from %s",
 597                     res->hr_remoteaddr);
 598                 goto close;
 599         }
 600         errmsg = nv_get_string(nvin, "errmsg");
 601         if (errmsg != NULL) {
 602                 pjdlog_warning("%s", errmsg);
 603                 if (nv_exists(nvin, "wait"))
 604                         error = EBUSY;
 605                 nv_free(nvin);
 606                 goto close;
 607         }
 608         token = nv_get_uint8_array(nvin, &size, "token");
 609         if (token == NULL) {
 610                 pjdlog_warning("Handshake header from %s has no 'token' field.",
 611                     res->hr_remoteaddr);
 612                 nv_free(nvin);
 613                 goto close;
 614         }
 615         if (size != sizeof(res->hr_token)) {
 616                 pjdlog_warning("Handshake header from %s contains 'token' of wrong size (got %zu, expected %zu).",
 617                     res->hr_remoteaddr, size, sizeof(res->hr_token));
 618                 nv_free(nvin);
 619                 goto close;
 620         }
 621         bcopy(token, res->hr_token, sizeof(res->hr_token));
 622         nv_free(nvin);
 623
 624         /*
 625          * Second handshake step.
 626          * Setup incoming connection with remote node.
 627          */
 628         if (primary_connect(res, &in) == -1)
 629                 goto close;
 630
 631         nvout = nv_alloc();
 632         nv_add_string(nvout, res->hr_name, "resource");
 633         nv_add_uint8_array(nvout, res->hr_token, sizeof(res->hr_token),
 634             "token");
 635         if (res->hr_resuid == 0) {
 636                 /*
 637                  * The resuid field was not yet initialized.
 638                  * Because we do synchronization inside init_resuid(), it is
 639                  * possible that someone already initialized it, the function
 640                  * will return false then, but if we successfully initialized
 641                  * it, we will get true. True means that there were no writes
 642                  * to this resource yet and we want to inform secondary that
 643                  * synchronization is not needed by sending "virgin" argument.
 644                  */
 645                 if (init_resuid(res))
 646                         nv_add_int8(nvout, 1, "virgin");
 647         }
 648         nv_add_uint64(nvout, res->hr_resuid, "resuid");
 649         nv_add_uint64(nvout, res->hr_primary_localcnt, "localcnt");
 650         nv_add_uint64(nvout, res->hr_primary_remotecnt, "remotecnt");
 651         if (nv_error(nvout) != 0) {
 652                 pjdlog_common(LOG_WARNING, 0, nv_error(nvout),
 653                     "Unable to allocate header for connection with %s",
 654                     res->hr_remoteaddr);
 655                 nv_free(nvout);
 656                 goto close;
 657         }
 658         if (hast_proto_send(res, in, nvout, NULL, 0) == -1) {
 659                 pjdlog_errno(LOG_WARNING,
 660                     "Unable to send handshake header to %s",
 661                     res->hr_remoteaddr);
 662                 nv_free(nvout);
 663                 goto close;
 664         }
 665         nv_free(nvout);
 666         if (hast_proto_recv_hdr(out, &nvin) == -1) {
 667                 pjdlog_errno(LOG_WARNING,
 668                     "Unable to receive handshake header from %s",
 669                     res->hr_remoteaddr);
 670                 goto close;
 671         }
 672         errmsg = nv_get_string(nvin, "errmsg");
 673         if (errmsg != NULL) {
 674                 pjdlog_warning("%s", errmsg);
 675                 nv_free(nvin);
 676                 goto close;
 677         }
 678         datasize = nv_get_int64(nvin, "datasize");
 679         if (datasize != res->hr_datasize) {
 680                 pjdlog_warning("Data size differs between nodes (local=%jd, remote=%jd).",
 681                     (intmax_t)res->hr_datasize, (intmax_t)datasize);
 682                 nv_free(nvin);
 683                 goto close;
 684         }
 685         extentsize = nv_get_int32(nvin, "extentsize");
 686         if (extentsize != res->hr_extentsize) {
 687                 pjdlog_warning("Extent size differs between nodes (local=%zd, remote=%zd).",
 688                     (ssize_t)res->hr_extentsize, (ssize_t)extentsize);
 689                 nv_free(nvin);
 690                 goto close;
 691         }
 692         res->hr_secondary_localcnt = nv_get_uint64(nvin, "localcnt");
 693         res->hr_secondary_remotecnt = nv_get_uint64(nvin, "remotecnt");
 694         res->hr_syncsrc = nv_get_uint8(nvin, "syncsrc");
 695         if (nv_exists(nvin, "virgin")) {
 696                 /*
 697                  * Secondary was reinitialized, bump localcnt if it is 0 as
 698                  * only we have the data.
 699                  */
 700                 PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_PRIMARY);
 701                 PJDLOG_ASSERT(res->hr_secondary_localcnt == 0);
 702
 703                 if (res->hr_primary_localcnt == 0) {
 704                         PJDLOG_ASSERT(res->hr_secondary_remotecnt == 0);
 705
 706                         mtx_lock(&metadata_lock);
 707                         res->hr_primary_localcnt++;
 708                         pjdlog_debug(1, "Increasing localcnt to %ju.",
 709                             (uintmax_t)res->hr_primary_localcnt);
 710                         (void)metadata_write(res);
 711                         mtx_unlock(&metadata_lock);
 712                 }
 713         }
 714         map = NULL;
 715         mapsize = nv_get_uint32(nvin, "mapsize");
 716         if (mapsize > 0) {
 717                 map = malloc(mapsize);
 718                 if (map == NULL) {
 719                         pjdlog_error("Unable to allocate memory for remote activemap (mapsize=%ju).",
 720                             (uintmax_t)mapsize);
 721                         nv_free(nvin);
 722                         goto close;
 723                 }
 724                 /*
 725                  * Remote node have some dirty extents on its own, lets
 726                  * download its activemap.
 727                  */
 728                 if (hast_proto_recv_data(res, out, nvin, map,
 729                     mapsize) == -1) {
 730                         pjdlog_errno(LOG_ERR,
 731                             "Unable to receive remote activemap");
 732                         nv_free(nvin);
 733                         free(map);
 734                         goto close;
 735                 }
 736                 /*
 737                  * Merge local and remote bitmaps.
 738                  */
 739                 activemap_merge(res->hr_amp, map, mapsize);
 740                 free(map);
 741                 /*
 742                  * Now that we merged bitmaps from both nodes, flush it to the
 743                  * disk before we start to synchronize.
 744                  */
 745                 (void)hast_activemap_flush(res);
 746         }
 747         nv_free(nvin);
 748 #ifdef notyet
 749         /* Setup directions. */
 750         if (proto_send(out, NULL, 0) == -1)
 751                 pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
 752         if (proto_recv(in, NULL, 0) == -1)
 753                 pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
 754 #endif
 755         pjdlog_info("Connected to %s.", res->hr_remoteaddr);
 756         if (inp != NULL && outp != NULL) {
 757                 *inp = in;
 758                 *outp = out;
 759         } else {
 760                 res->hr_remotein = in;
 761                 res->hr_remoteout = out;
 762         }
 763         event_send(res, EVENT_CONNECT);
 764         return (0);
 765 close:
 766         if (errmsg != NULL && strcmp(errmsg, "Split-brain condition!") == 0)
 767                 event_send(res, EVENT_SPLITBRAIN);
 768         proto_close(out);
 769         if (in != NULL)
 770                 proto_close(in);
 771         return (error);
 772 }
 773
 774 static void
 775 sync_start(void)
 776 {
 777
 778         mtx_lock(&sync_lock);
 779         sync_inprogress = true;
 780         mtx_unlock(&sync_lock);
 781         cv_signal(&sync_cond);
 782 }
 783
 784 static void
 785 sync_stop(void)
 786 {
 787
 788         mtx_lock(&sync_lock);
 789         if (sync_inprogress)
 790                 sync_inprogress = false;
 791         mtx_unlock(&sync_lock);
 792 }
 793
 794 static void
 795 init_ggate(struct hast_resource *res)
 796 {
 797         struct g_gate_ctl_create ggiocreate;
 798         struct g_gate_ctl_cancel ggiocancel;
 799
 800         /*
 801          * We communicate with ggate via /dev/ggctl. Open it.
 802          */
 803         res->hr_ggatefd = open("/dev/" G_GATE_CTL_NAME, O_RDWR);
 804         if (res->hr_ggatefd == -1)
 805                 primary_exit(EX_OSFILE, "Unable to open /dev/" G_GATE_CTL_NAME);
 806         /*
 807          * Create provider before trying to connect, as connection failure
 808          * is not critical, but may take some time.
 809          */
 810         bzero(&ggiocreate, sizeof(ggiocreate));
 811         ggiocreate.gctl_version = G_GATE_VERSION;
 812         ggiocreate.gctl_mediasize = res->hr_datasize;
 813         ggiocreate.gctl_sectorsize = res->hr_local_sectorsize;
 814         ggiocreate.gctl_flags = 0;
 815         ggiocreate.gctl_maxcount = 0;
 816         ggiocreate.gctl_timeout = 0;
 817         ggiocreate.gctl_unit = G_GATE_NAME_GIVEN;
 818         snprintf(ggiocreate.gctl_name, sizeof(ggiocreate.gctl_name), "hast/%s",
 819             res->hr_provname);
 820         if (ioctl(res->hr_ggatefd, G_GATE_CMD_CREATE, &ggiocreate) == 0) {
 821                 pjdlog_info("Device hast/%s created.", res->hr_provname);
 822                 res->hr_ggateunit = ggiocreate.gctl_unit;
 823                 return;
 824         }
 825         if (errno != EEXIST) {
 826                 primary_exit(EX_OSERR, "Unable to create hast/%s device",
 827                     res->hr_provname);
 828         }
 829         pjdlog_debug(1,
 830             "Device hast/%s already exists, we will try to take it over.",
 831             res->hr_provname);
 832         /*
 833          * If we received EEXIST, we assume that the process who created the
 834          * provider died and didn't clean up. In that case we will start from
 835          * where he left of.
 836          */
 837         bzero(&ggiocancel, sizeof(ggiocancel));
 838         ggiocancel.gctl_version = G_GATE_VERSION;
 839         ggiocancel.gctl_unit = G_GATE_NAME_GIVEN;
 840         snprintf(ggiocancel.gctl_name, sizeof(ggiocancel.gctl_name), "hast/%s",
 841             res->hr_provname);
 842         if (ioctl(res->hr_ggatefd, G_GATE_CMD_CANCEL, &ggiocancel) == 0) {
 843                 pjdlog_info("Device hast/%s recovered.", res->hr_provname);
 844                 res->hr_ggateunit = ggiocancel.gctl_unit;
 845                 return;
 846         }
 847         primary_exit(EX_OSERR, "Unable to take over hast/%s device",
 848             res->hr_provname);
 849 }
 850
 851 void
 852 hastd_primary(struct hast_resource *res)
 853 {
 854         pthread_t td;
 855         pid_t pid;
 856         int error, mode, debuglevel;
 857
 858         /*
 859          * Create communication channel for sending control commands from
 860          * parent to child.
 861          */
 862         if (proto_client(NULL, "socketpair://", &res->hr_ctrl) == -1) {
 863                 /* TODO: There's no need for this to be fatal error. */
 864                 KEEP_ERRNO((void)pidfile_remove(pfh));
 865                 pjdlog_exit(EX_OSERR,
 866                     "Unable to create control sockets between parent and child");
 867         }
 868         /*
 869          * Create communication channel for sending events from child to parent.
 870          */
 871         if (proto_client(NULL, "socketpair://", &res->hr_event) == -1) {
 872                 /* TODO: There's no need for this to be fatal error. */
 873                 KEEP_ERRNO((void)pidfile_remove(pfh));
 874                 pjdlog_exit(EX_OSERR,
 875                     "Unable to create event sockets between child and parent");
 876         }
 877         /*
 878          * Create communication channel for sending connection requests from
 879          * child to parent.
 880          */
 881         if (proto_client(NULL, "socketpair://", &res->hr_conn) == -1) {
 882                 /* TODO: There's no need for this to be fatal error. */
 883                 KEEP_ERRNO((void)pidfile_remove(pfh));
 884                 pjdlog_exit(EX_OSERR,
 885                     "Unable to create connection sockets between child and parent");
 886         }
 887
 888         pid = fork();
 889         if (pid == -1) {
 890                 /* TODO: There's no need for this to be fatal error. */
 891                 KEEP_ERRNO((void)pidfile_remove(pfh));
 892                 pjdlog_exit(EX_TEMPFAIL, "Unable to fork");
 893         }
 894
 895         if (pid > 0) {
 896                 /* This is parent. */
 897                 /* Declare that we are receiver. */
 898                 proto_recv(res->hr_event, NULL, 0);
 899                 proto_recv(res->hr_conn, NULL, 0);
 900                 /* Declare that we are sender. */
 901                 proto_send(res->hr_ctrl, NULL, 0);
 902                 res->hr_workerpid = pid;
 903                 return;
 904         }
 905
 906         gres = res;
 907         mode = pjdlog_mode_get();
 908         debuglevel = pjdlog_debug_get();
 909
 910         /* Declare that we are sender. */
 911         proto_send(res->hr_event, NULL, 0);
 912         proto_send(res->hr_conn, NULL, 0);
 913         /* Declare that we are receiver. */
 914         proto_recv(res->hr_ctrl, NULL, 0);
 915         descriptors_cleanup(res);
 916
 917         descriptors_assert(res, mode);
 918
 919         pjdlog_init(mode);
 920         pjdlog_debug_set(debuglevel);
 921         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 922         setproctitle("%s (%s)", res->hr_name, role2str(res->hr_role));
 923
 924         init_local(res);
 925         init_ggate(res);
 926         init_environment(res);
 927
 928         if (drop_privs(res) != 0) {
 929                 cleanup(res);
 930                 exit(EX_CONFIG);
 931         }
 932         pjdlog_info("Privileges successfully dropped.");
 933
 934         /*
 935          * Create the guard thread first, so we can handle signals from the
 936          * very beginning.
 937          */
 938         error = pthread_create(&td, NULL, guard_thread, res);
 939         PJDLOG_ASSERT(error == 0);
 940         /*
 941          * Create the control thread before sending any event to the parent,
 942          * as we can deadlock when parent sends control request to worker,
 943          * but worker has no control thread started yet, so parent waits.
 944          * In the meantime worker sends an event to the parent, but parent
 945          * is unable to handle the event, because it waits for control
 946          * request response.
 947          */
 948         error = pthread_create(&td, NULL, ctrl_thread, res);
 949         PJDLOG_ASSERT(error == 0);
 950         if (real_remote(res)) {
 951                 error = init_remote(res, NULL, NULL);
 952                 if (error == 0) {
 953                         sync_start();
 954                 } else if (error == EBUSY) {
 955                         time_t start = time(NULL);
 956
 957                         pjdlog_warning("Waiting for remote node to become %s for %ds.",
 958                             role2str(HAST_ROLE_SECONDARY),
 959                             res->hr_timeout);
 960                         for (;;) {
 961                                 sleep(1);
 962                                 error = init_remote(res, NULL, NULL);
 963                                 if (error != EBUSY)
 964                                         break;
 965                                 if (time(NULL) > start + res->hr_timeout)
 966                                         break;
 967                         }
 968                         if (error == EBUSY) {
 969                                 pjdlog_warning("Remote node is still %s, starting anyway.",
 970                                     role2str(HAST_ROLE_PRIMARY));
 971                         }
 972                 }
 973         }
 974         error = pthread_create(&td, NULL, ggate_recv_thread, res);
 975         PJDLOG_ASSERT(error == 0);
 976         error = pthread_create(&td, NULL, local_send_thread, res);
 977         PJDLOG_ASSERT(error == 0);
 978         error = pthread_create(&td, NULL, remote_send_thread, res);
 979         PJDLOG_ASSERT(error == 0);
 980         error = pthread_create(&td, NULL, remote_recv_thread, res);
 981         PJDLOG_ASSERT(error == 0);
 982         error = pthread_create(&td, NULL, ggate_send_thread, res);
 983         PJDLOG_ASSERT(error == 0);
 984         fullystarted = true;
 985         (void)sync_thread(res);
 986 }
 987
 988 static void
 989 reqlog(int loglevel, int debuglevel, struct g_gate_ctl_io *ggio, const char *fmt, ...)
 990 {
 991         char msg[1024];
 992         va_list ap;
 993
 994         va_start(ap, fmt);
 995         (void)vsnprintf(msg, sizeof(msg), fmt, ap);
 996         va_end(ap);
 997         switch (ggio->gctl_cmd) {
 998         case BIO_READ:
 999                 (void)snprlcat(msg, sizeof(msg), "READ(%ju, %ju).",
1000                     (uintmax_t)ggio->gctl_offset,
1001                     (uintmax_t)ggio->gctl_length);
1002                 break;
1003         case BIO_DELETE:
1004                 (void)snprlcat(msg, sizeof(msg), "DELETE(%ju, %ju).",
1005                     (uintmax_t)ggio->gctl_offset,
1006                     (uintmax_t)ggio->gctl_length);
1007                 break;
1008         case BIO_FLUSH:
1009                 (void)snprlcat(msg, sizeof(msg), "FLUSH.");
1010                 break;
1011         case BIO_WRITE:
1012                 (void)snprlcat(msg, sizeof(msg), "WRITE(%ju, %ju).",
1013                     (uintmax_t)ggio->gctl_offset,
1014                     (uintmax_t)ggio->gctl_length);
1015                 break;
1016         default:
1017                 (void)snprlcat(msg, sizeof(msg), "UNKNOWN(%u).",
1018                     (unsigned int)ggio->gctl_cmd);
1019                 break;
1020         }
1021         pjdlog_common(loglevel, debuglevel, -1, "%s", msg);
1022 }
1023
1024 static void
1025 remote_close(struct hast_resource *res, int ncomp)
1026 {
1027
1028         rw_wlock(&hio_remote_lock[ncomp]);
1029         /*
1030          * Check for a race between dropping rlock and acquiring wlock -
1031          * another thread can close connection in-between.
1032          */
1033         if (!ISCONNECTED(res, ncomp)) {
1034                 PJDLOG_ASSERT(res->hr_remotein == NULL);
1035                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
1036                 rw_unlock(&hio_remote_lock[ncomp]);
1037                 return;
1038         }
1039
1040         PJDLOG_ASSERT(res->hr_remotein != NULL);
1041         PJDLOG_ASSERT(res->hr_remoteout != NULL);
1042
1043         pjdlog_debug(2, "Closing incoming connection to %s.",
1044             res->hr_remoteaddr);
1045         proto_close(res->hr_remotein);
1046         res->hr_remotein = NULL;
1047         pjdlog_debug(2, "Closing outgoing connection to %s.",
1048             res->hr_remoteaddr);
1049         proto_close(res->hr_remoteout);
1050         res->hr_remoteout = NULL;
1051
1052         rw_unlock(&hio_remote_lock[ncomp]);
1053
1054         pjdlog_warning("Disconnected from %s.", res->hr_remoteaddr);
1055
1056         /*
1057          * Stop synchronization if in-progress.
1058          */
1059         sync_stop();
1060
1061         event_send(res, EVENT_DISCONNECT);
1062 }
1063
1064 /*
1065  * Acknowledge write completion to the kernel, but don't update activemap yet.
1066  */
1067 static void
1068 write_complete(struct hast_resource *res, struct hio *hio)
1069 {
1070         struct g_gate_ctl_io *ggio;
1071         unsigned int ncomp;
1072
1073         PJDLOG_ASSERT(!hio->hio_done);
1074
1075         ggio = &hio->hio_ggio;
1076         PJDLOG_ASSERT(ggio->gctl_cmd == BIO_WRITE);
1077
1078         /*
1079          * Bump local count if this is first write after
1080          * connection failure with remote node.
1081          */
1082         ncomp = 1;
1083         rw_rlock(&hio_remote_lock[ncomp]);
1084         if (!ISCONNECTED(res, ncomp)) {
1085                 mtx_lock(&metadata_lock);
1086                 if (res->hr_primary_localcnt == res->hr_secondary_remotecnt) {
1087                         res->hr_primary_localcnt++;
1088                         pjdlog_debug(1, "Increasing localcnt to %ju.",
1089                             (uintmax_t)res->hr_primary_localcnt);
1090                         (void)metadata_write(res);
1091                 }
1092                 mtx_unlock(&metadata_lock);
1093         }
1094         rw_unlock(&hio_remote_lock[ncomp]);
1095         if (ioctl(res->hr_ggatefd, G_GATE_CMD_DONE, ggio) == -1)
1096                 primary_exit(EX_OSERR, "G_GATE_CMD_DONE failed");
1097         hio->hio_done = true;
1098 }
1099
1100 /*
1101  * Thread receives ggate I/O requests from the kernel and passes them to
1102  * appropriate threads:
1103  * WRITE - always goes to both local_send and remote_send threads
1104  * READ (when the block is up-to-date on local component) -
1105  *      only local_send thread
1106  * READ (when the block isn't up-to-date on local component) -
1107  *      only remote_send thread
1108  * DELETE - always goes to both local_send and remote_send threads
1109  * FLUSH - always goes to both local_send and remote_send threads
1110  */
1111 static void *
1112 ggate_recv_thread(void *arg)
1113 {
1114         struct hast_resource *res = arg;
1115         struct g_gate_ctl_io *ggio;
1116         struct hio *hio;
1117         unsigned int ii, ncomp, ncomps;
1118         int error;
1119
1120         for (;;) {
1121                 pjdlog_debug(2, "ggate_recv: Taking free request.");
1122                 QUEUE_TAKE2(hio, free);
1123                 pjdlog_debug(2, "ggate_recv: (%p) Got free request.", hio);
1124                 ggio = &hio->hio_ggio;
1125                 ggio->gctl_unit = res->hr_ggateunit;
1126                 ggio->gctl_length = MAXPHYS;
1127                 ggio->gctl_error = 0;
1128                 hio->hio_done = false;
1129                 hio->hio_replication = res->hr_replication;
1130                 pjdlog_debug(2,
1131                     "ggate_recv: (%p) Waiting for request from the kernel.",
1132                     hio);
1133                 if (ioctl(res->hr_ggatefd, G_GATE_CMD_START, ggio) == -1) {
1134                         if (sigexit_received)
1135                                 pthread_exit(NULL);
1136                         primary_exit(EX_OSERR, "G_GATE_CMD_START failed");
1137                 }
1138                 error = ggio->gctl_error;
1139                 switch (error) {
1140                 case 0:
1141                         break;
1142                 case ECANCELED:
1143                         /* Exit gracefully. */
1144                         if (!sigexit_received) {
1145                                 pjdlog_debug(2,
1146                                     "ggate_recv: (%p) Received cancel from the kernel.",
1147                                     hio);
1148                                 pjdlog_info("Received cancel from the kernel, exiting.");
1149                         }
1150                         pthread_exit(NULL);
1151                 case ENOMEM:
1152                         /*
1153                          * Buffer too small? Impossible, we allocate MAXPHYS
1154                          * bytes - request can't be bigger than that.
1155                          */
1156                         /* FALLTHROUGH */
1157                 case ENXIO:
1158                 default:
1159                         primary_exitx(EX_OSERR, "G_GATE_CMD_START failed: %s.",
1160                             strerror(error));
1161                 }
1162
1163                 ncomp = 0;
1164                 ncomps = HAST_NCOMPONENTS;
1165
1166                 for (ii = 0; ii < ncomps; ii++)
1167                         hio->hio_errors[ii] = EINVAL;
1168                 reqlog(LOG_DEBUG, 2, ggio,
1169                     "ggate_recv: (%p) Request received from the kernel: ",
1170                     hio);
1171
1172                 /*
1173                  * Inform all components about new write request.
1174                  * For read request prefer local component unless the given
1175                  * range is out-of-date, then use remote component.
1176                  */
1177                 switch (ggio->gctl_cmd) {
1178                 case BIO_READ:
1179                         res->hr_stat_read++;
1180                         ncomps = 1;
1181                         mtx_lock(&metadata_lock);
1182                         if (res->hr_syncsrc == HAST_SYNCSRC_UNDEF ||
1183                             res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1184                                 /*
1185                                  * This range is up-to-date on local component,
1186                                  * so handle request locally.
1187                                  */
1188                                  /* Local component is 0 for now. */
1189                                 ncomp = 0;
1190                         } else /* if (res->hr_syncsrc ==
1191                             HAST_SYNCSRC_SECONDARY) */ {
1192                                 PJDLOG_ASSERT(res->hr_syncsrc ==
1193                                     HAST_SYNCSRC_SECONDARY);
1194                                 /*
1195                                  * This range is out-of-date on local component,
1196                                  * so send request to the remote node.
1197                                  */
1198                                  /* Remote component is 1 for now. */
1199                                 ncomp = 1;
1200                         }
1201                         mtx_unlock(&metadata_lock);
1202                         break;
1203                 case BIO_WRITE:
1204                         res->hr_stat_write++;
1205                         if (res->hr_resuid == 0 &&
1206                             res->hr_primary_localcnt == 0) {
1207                                 /* This is first write. */
1208                                 res->hr_primary_localcnt = 1;
1209                         }
1210                         for (;;) {
1211                                 mtx_lock(&range_lock);
1212                                 if (rangelock_islocked(range_sync,
1213                                     ggio->gctl_offset, ggio->gctl_length)) {
1214                                         pjdlog_debug(2,
1215                                             "regular: Range offset=%jd length=%zu locked.",
1216                                             (intmax_t)ggio->gctl_offset,
1217                                             (size_t)ggio->gctl_length);
1218                                         range_regular_wait = true;
1219                                         cv_wait(&range_regular_cond, &range_lock);
1220                                         range_regular_wait = false;
1221                                         mtx_unlock(&range_lock);
1222                                         continue;
1223                                 }
1224                                 if (rangelock_add(range_regular,
1225                                     ggio->gctl_offset, ggio->gctl_length) == -1) {
1226                                         mtx_unlock(&range_lock);
1227                                         pjdlog_debug(2,
1228                                             "regular: Range offset=%jd length=%zu is already locked, waiting.",
1229                                             (intmax_t)ggio->gctl_offset,
1230                                             (size_t)ggio->gctl_length);
1231                                         sleep(1);
1232                                         continue;
1233                                 }
1234                                 mtx_unlock(&range_lock);
1235                                 break;
1236                         }
1237                         mtx_lock(&res->hr_amp_lock);
1238                         if (activemap_write_start(res->hr_amp,
1239                             ggio->gctl_offset, ggio->gctl_length)) {
1240                                 res->hr_stat_activemap_update++;
1241                                 (void)hast_activemap_flush(res);
1242                         }
1243                         mtx_unlock(&res->hr_amp_lock);
1244                         break;
1245                 case BIO_DELETE:
1246                         res->hr_stat_delete++;
1247                         break;
1248                 case BIO_FLUSH:
1249                         res->hr_stat_flush++;
1250                         break;
1251                 }
1252                 pjdlog_debug(2,
1253                     "ggate_recv: (%p) Moving request to the send queues.", hio);
1254                 refcount_init(&hio->hio_countdown, ncomps);
1255                 for (ii = ncomp; ii < ncomp + ncomps; ii++)
1256                         QUEUE_INSERT1(hio, send, ii);
1257         }
1258         /* NOTREACHED */
1259         return (NULL);
1260 }
1261
1262 /*
1263  * Thread reads from or writes to local component.
1264  * If local read fails, it redirects it to remote_send thread.
1265  */
1266 static void *
1267 local_send_thread(void *arg)
1268 {
1269         struct hast_resource *res = arg;
1270         struct g_gate_ctl_io *ggio;
1271         struct hio *hio;
1272         unsigned int ncomp, rncomp;
1273         ssize_t ret;
1274
1275         /* Local component is 0 for now. */
1276         ncomp = 0;
1277         /* Remote component is 1 for now. */
1278         rncomp = 1;
1279
1280         for (;;) {
1281                 pjdlog_debug(2, "local_send: Taking request.");
1282                 QUEUE_TAKE1(hio, send, ncomp, 0);
1283                 pjdlog_debug(2, "local_send: (%p) Got request.", hio);
1284                 ggio = &hio->hio_ggio;
1285                 switch (ggio->gctl_cmd) {
1286                 case BIO_READ:
1287                         ret = pread(res->hr_localfd, ggio->gctl_data,
1288                             ggio->gctl_length,
1289                             ggio->gctl_offset + res->hr_localoff);
1290                         if (ret == ggio->gctl_length)
1291                                 hio->hio_errors[ncomp] = 0;
1292                         else if (!ISSYNCREQ(hio)) {
1293                                 /*
1294                                  * If READ failed, try to read from remote node.
1295                                  */
1296                                 if (ret == -1) {
1297                                         reqlog(LOG_WARNING, 0, ggio,
1298                                             "Local request failed (%s), trying remote node. ",
1299                                             strerror(errno));
1300                                 } else if (ret != ggio->gctl_length) {
1301                                         reqlog(LOG_WARNING, 0, ggio,
1302                                             "Local request failed (%zd != %jd), trying remote node. ",
1303                                             ret, (intmax_t)ggio->gctl_length);
1304                                 }
1305                                 QUEUE_INSERT1(hio, send, rncomp);
1306                                 continue;
1307                         }
1308                         break;
1309                 case BIO_WRITE:
1310                         ret = pwrite(res->hr_localfd, ggio->gctl_data,
1311                             ggio->gctl_length,
1312                             ggio->gctl_offset + res->hr_localoff);
1313                         if (ret == -1) {
1314                                 hio->hio_errors[ncomp] = errno;
1315                                 reqlog(LOG_WARNING, 0, ggio,
1316                                     "Local request failed (%s): ",
1317                                     strerror(errno));
1318                         } else if (ret != ggio->gctl_length) {
1319                                 hio->hio_errors[ncomp] = EIO;
1320                                 reqlog(LOG_WARNING, 0, ggio,
1321                                     "Local request failed (%zd != %jd): ",
1322                                     ret, (intmax_t)ggio->gctl_length);
1323                         } else {
1324                                 hio->hio_errors[ncomp] = 0;
1325                                 if (hio->hio_replication ==
1326                                     HAST_REPLICATION_ASYNC &&
1327                                     !ISSYNCREQ(hio)) {
1328                                         ggio->gctl_error = 0;
1329                                         write_complete(res, hio);
1330                                 }
1331                         }
1332                         break;
1333                 case BIO_DELETE:
1334                         ret = g_delete(res->hr_localfd,
1335                             ggio->gctl_offset + res->hr_localoff,
1336                             ggio->gctl_length);
1337                         if (ret == -1) {
1338                                 hio->hio_errors[ncomp] = errno;
1339                                 reqlog(LOG_WARNING, 0, ggio,
1340                                     "Local request failed (%s): ",
1341                                     strerror(errno));
1342                         } else {
1343                                 hio->hio_errors[ncomp] = 0;
1344                         }
1345                         break;
1346                 case BIO_FLUSH:
1347                         if (!res->hr_localflush) {
1348                                 ret = -1;
1349                                 errno = EOPNOTSUPP;
1350                                 break;
1351                         }
1352                         ret = g_flush(res->hr_localfd);
1353                         if (ret == -1) {
1354                                 if (errno == EOPNOTSUPP)
1355                                         res->hr_localflush = false;
1356                                 hio->hio_errors[ncomp] = errno;
1357                                 reqlog(LOG_WARNING, 0, ggio,
1358                                     "Local request failed (%s): ",
1359                                     strerror(errno));
1360                         } else {
1361                                 hio->hio_errors[ncomp] = 0;
1362                         }
1363                         break;
1364                 }
1365                 if (!refcount_release(&hio->hio_countdown))
1366                         continue;
1367                 if (ISSYNCREQ(hio)) {
1368                         mtx_lock(&sync_lock);
1369                         SYNCREQDONE(hio);
1370                         mtx_unlock(&sync_lock);
1371                         cv_signal(&sync_cond);
1372                 } else {
1373                         pjdlog_debug(2,
1374                             "local_send: (%p) Moving request to the done queue.",
1375                             hio);
1376                         QUEUE_INSERT2(hio, done);
1377                 }
1378         }
1379         /* NOTREACHED */
1380         return (NULL);
1381 }
1382
1383 static void
1384 keepalive_send(struct hast_resource *res, unsigned int ncomp)
1385 {
1386         struct nv *nv;
1387
1388         rw_rlock(&hio_remote_lock[ncomp]);
1389
1390         if (!ISCONNECTED(res, ncomp)) {
1391                 rw_unlock(&hio_remote_lock[ncomp]);
1392                 return;
1393         }
1394
1395         PJDLOG_ASSERT(res->hr_remotein != NULL);
1396         PJDLOG_ASSERT(res->hr_remoteout != NULL);
1397
1398         nv = nv_alloc();
1399         nv_add_uint8(nv, HIO_KEEPALIVE, "cmd");
1400         if (nv_error(nv) != 0) {
1401                 rw_unlock(&hio_remote_lock[ncomp]);
1402                 nv_free(nv);
1403                 pjdlog_debug(1,
1404                     "keepalive_send: Unable to prepare header to send.");
1405                 return;
1406         }
1407         if (hast_proto_send(res, res->hr_remoteout, nv, NULL, 0) == -1) {
1408                 rw_unlock(&hio_remote_lock[ncomp]);
1409                 pjdlog_common(LOG_DEBUG, 1, errno,
1410                     "keepalive_send: Unable to send request");
1411                 nv_free(nv);
1412                 remote_close(res, ncomp);
1413                 return;
1414         }
1415
1416         rw_unlock(&hio_remote_lock[ncomp]);
1417         nv_free(nv);
1418         pjdlog_debug(2, "keepalive_send: Request sent.");
1419 }
1420
1421 /*
1422  * Thread sends request to secondary node.
1423  */
1424 static void *
1425 remote_send_thread(void *arg)
1426 {
1427         struct hast_resource *res = arg;
1428         struct g_gate_ctl_io *ggio;
1429         time_t lastcheck, now;
1430         struct hio *hio;
1431         struct nv *nv;
1432         unsigned int ncomp;
1433         bool wakeup;
1434         uint64_t offset, length;
1435         uint8_t cmd;
1436         void *data;
1437
1438         /* Remote component is 1 for now. */
1439         ncomp = 1;
1440         lastcheck = time(NULL);
1441
1442         for (;;) {
1443                 pjdlog_debug(2, "remote_send: Taking request.");
1444                 QUEUE_TAKE1(hio, send, ncomp, HAST_KEEPALIVE);
1445                 if (hio == NULL) {
1446                         now = time(NULL);
1447                         if (lastcheck + HAST_KEEPALIVE <= now) {
1448                                 keepalive_send(res, ncomp);
1449                                 lastcheck = now;
1450                         }
1451                         continue;
1452                 }
1453                 pjdlog_debug(2, "remote_send: (%p) Got request.", hio);
1454                 ggio = &hio->hio_ggio;
1455                 switch (ggio->gctl_cmd) {
1456                 case BIO_READ:
1457                         cmd = HIO_READ;
1458                         data = NULL;
1459                         offset = ggio->gctl_offset;
1460                         length = ggio->gctl_length;
1461                         break;
1462                 case BIO_WRITE:
1463                         cmd = HIO_WRITE;
1464                         data = ggio->gctl_data;
1465                         offset = ggio->gctl_offset;
1466                         length = ggio->gctl_length;
1467                         break;
1468                 case BIO_DELETE:
1469                         cmd = HIO_DELETE;
1470                         data = NULL;
1471                         offset = ggio->gctl_offset;
1472                         length = ggio->gctl_length;
1473                         break;
1474                 case BIO_FLUSH:
1475                         cmd = HIO_FLUSH;
1476                         data = NULL;
1477                         offset = 0;
1478                         length = 0;
1479                         break;
1480                 default:
1481                         PJDLOG_ABORT("invalid condition");
1482                 }
1483                 nv = nv_alloc();
1484                 nv_add_uint8(nv, cmd, "cmd");
1485                 nv_add_uint64(nv, (uint64_t)ggio->gctl_seq, "seq");
1486                 nv_add_uint64(nv, offset, "offset");
1487                 nv_add_uint64(nv, length, "length");
1488                 if (nv_error(nv) != 0) {
1489                         hio->hio_errors[ncomp] = nv_error(nv);
1490                         pjdlog_debug(2,
1491                             "remote_send: (%p) Unable to prepare header to send.",
1492                             hio);
1493                         reqlog(LOG_ERR, 0, ggio,
1494                             "Unable to prepare header to send (%s): ",
1495                             strerror(nv_error(nv)));
1496                         /* Move failed request immediately to the done queue. */
1497                         goto done_queue;
1498                 }
1499                 /*
1500                  * Protect connection from disappearing.
1501                  */
1502                 rw_rlock(&hio_remote_lock[ncomp]);
1503                 if (!ISCONNECTED(res, ncomp)) {
1504                         rw_unlock(&hio_remote_lock[ncomp]);
1505                         hio->hio_errors[ncomp] = ENOTCONN;
1506                         goto done_queue;
1507                 }
1508                 /*
1509                  * Move the request to recv queue before sending it, because
1510                  * in different order we can get reply before we move request
1511                  * to recv queue.
1512                  */
1513                 pjdlog_debug(2,
1514                     "remote_send: (%p) Moving request to the recv queue.",
1515                     hio);
1516                 mtx_lock(&hio_recv_list_lock[ncomp]);
1517                 wakeup = TAILQ_EMPTY(&hio_recv_list[ncomp]);
1518                 TAILQ_INSERT_TAIL(&hio_recv_list[ncomp], hio, hio_next[ncomp]);
1519                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1520                 if (hast_proto_send(res, res->hr_remoteout, nv, data,
1521                     data != NULL ? length : 0) == -1) {
1522                         hio->hio_errors[ncomp] = errno;
1523                         rw_unlock(&hio_remote_lock[ncomp]);
1524                         pjdlog_debug(2,
1525                             "remote_send: (%p) Unable to send request.", hio);
1526                         reqlog(LOG_ERR, 0, ggio,
1527                             "Unable to send request (%s): ",
1528                             strerror(hio->hio_errors[ncomp]));
1529                         remote_close(res, ncomp);
1530                         /*
1531                          * Take request back from the receive queue and move
1532                          * it immediately to the done queue.
1533                          */
1534                         mtx_lock(&hio_recv_list_lock[ncomp]);
1535                         TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1536                             hio_next[ncomp]);
1537                         mtx_unlock(&hio_recv_list_lock[ncomp]);
1538                         goto done_queue;
1539                 }
1540                 rw_unlock(&hio_remote_lock[ncomp]);
1541                 nv_free(nv);
1542                 if (wakeup)
1543                         cv_signal(&hio_recv_list_cond[ncomp]);
1544                 continue;
1545 done_queue:
1546                 nv_free(nv);
1547                 if (ISSYNCREQ(hio)) {
1548                         if (!refcount_release(&hio->hio_countdown))
1549                                 continue;
1550                         mtx_lock(&sync_lock);
1551                         SYNCREQDONE(hio);
1552                         mtx_unlock(&sync_lock);
1553                         cv_signal(&sync_cond);
1554                         continue;
1555                 }
1556                 if (ggio->gctl_cmd == BIO_WRITE) {
1557                         mtx_lock(&res->hr_amp_lock);
1558                         if (activemap_need_sync(res->hr_amp, ggio->gctl_offset,
1559                             ggio->gctl_length)) {
1560                                 (void)hast_activemap_flush(res);
1561                         }
1562                         mtx_unlock(&res->hr_amp_lock);
1563                 }
1564                 if (!refcount_release(&hio->hio_countdown))
1565                         continue;
1566                 pjdlog_debug(2,
1567                     "remote_send: (%p) Moving request to the done queue.",
1568                     hio);
1569                 QUEUE_INSERT2(hio, done);
1570         }
1571         /* NOTREACHED */
1572         return (NULL);
1573 }
1574
1575 /*
1576  * Thread receives answer from secondary node and passes it to ggate_send
1577  * thread.
1578  */
1579 static void *
1580 remote_recv_thread(void *arg)
1581 {
1582         struct hast_resource *res = arg;
1583         struct g_gate_ctl_io *ggio;
1584         struct hio *hio;
1585         struct nv *nv;
1586         unsigned int ncomp;
1587         uint64_t seq;
1588         int error;
1589
1590         /* Remote component is 1 for now. */
1591         ncomp = 1;
1592
1593         for (;;) {
1594                 /* Wait until there is anything to receive. */
1595                 mtx_lock(&hio_recv_list_lock[ncomp]);
1596                 while (TAILQ_EMPTY(&hio_recv_list[ncomp])) {
1597                         pjdlog_debug(2, "remote_recv: No requests, waiting.");
1598                         cv_wait(&hio_recv_list_cond[ncomp],
1599                             &hio_recv_list_lock[ncomp]);
1600                 }
1601                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1602
1603                 rw_rlock(&hio_remote_lock[ncomp]);
1604                 if (!ISCONNECTED(res, ncomp)) {
1605                         rw_unlock(&hio_remote_lock[ncomp]);
1606                         /*
1607                          * Connection is dead, so move all pending requests to
1608                          * the done queue (one-by-one).
1609                          */
1610                         mtx_lock(&hio_recv_list_lock[ncomp]);
1611                         hio = TAILQ_FIRST(&hio_recv_list[ncomp]);
1612                         PJDLOG_ASSERT(hio != NULL);
1613                         TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1614                             hio_next[ncomp]);
1615                         mtx_unlock(&hio_recv_list_lock[ncomp]);
1616                         goto done_queue;
1617                 }
1618                 if (hast_proto_recv_hdr(res->hr_remotein, &nv) == -1) {
1619                         pjdlog_errno(LOG_ERR,
1620                             "Unable to receive reply header");
1621                         rw_unlock(&hio_remote_lock[ncomp]);
1622                         remote_close(res, ncomp);
1623                         continue;
1624                 }
1625                 rw_unlock(&hio_remote_lock[ncomp]);
1626                 seq = nv_get_uint64(nv, "seq");
1627                 if (seq == 0) {
1628                         pjdlog_error("Header contains no 'seq' field.");
1629                         nv_free(nv);
1630                         continue;
1631                 }
1632                 mtx_lock(&hio_recv_list_lock[ncomp]);
1633                 TAILQ_FOREACH(hio, &hio_recv_list[ncomp], hio_next[ncomp]) {
1634                         if (hio->hio_ggio.gctl_seq == seq) {
1635                                 TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1636                                     hio_next[ncomp]);
1637                                 break;
1638                         }
1639                 }
1640                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1641                 if (hio == NULL) {
1642                         pjdlog_error("Found no request matching received 'seq' field (%ju).",
1643                             (uintmax_t)seq);
1644                         nv_free(nv);
1645                         continue;
1646                 }
1647                 ggio = &hio->hio_ggio;
1648                 error = nv_get_int16(nv, "error");
1649                 if (error != 0) {
1650                         /* Request failed on remote side. */
1651                         hio->hio_errors[ncomp] = error;
1652                         reqlog(LOG_WARNING, 0, ggio,
1653                             "Remote request failed (%s): ", strerror(error));
1654                         nv_free(nv);
1655                         goto done_queue;
1656                 }
1657                 switch (ggio->gctl_cmd) {
1658                 case BIO_READ:
1659                         rw_rlock(&hio_remote_lock[ncomp]);
1660                         if (!ISCONNECTED(res, ncomp)) {
1661                                 rw_unlock(&hio_remote_lock[ncomp]);
1662                                 nv_free(nv);
1663                                 goto done_queue;
1664                         }
1665                         if (hast_proto_recv_data(res, res->hr_remotein, nv,
1666                             ggio->gctl_data, ggio->gctl_length) == -1) {
1667                                 hio->hio_errors[ncomp] = errno;
1668                                 pjdlog_errno(LOG_ERR,
1669                                     "Unable to receive reply data");
1670                                 rw_unlock(&hio_remote_lock[ncomp]);
1671                                 nv_free(nv);
1672                                 remote_close(res, ncomp);
1673                                 goto done_queue;
1674                         }
1675                         rw_unlock(&hio_remote_lock[ncomp]);
1676                         break;
1677                 case BIO_WRITE:
1678                 case BIO_DELETE:
1679                 case BIO_FLUSH:
1680                         break;
1681                 default:
1682                         PJDLOG_ABORT("invalid condition");
1683                 }
1684                 hio->hio_errors[ncomp] = 0;
1685                 nv_free(nv);
1686 done_queue:
1687                 if (!refcount_release(&hio->hio_countdown))
1688                         continue;
1689                 if (ISSYNCREQ(hio)) {
1690                         mtx_lock(&sync_lock);
1691                         SYNCREQDONE(hio);
1692                         mtx_unlock(&sync_lock);
1693                         cv_signal(&sync_cond);
1694                 } else {
1695                         pjdlog_debug(2,
1696                             "remote_recv: (%p) Moving request to the done queue.",
1697                             hio);
1698                         QUEUE_INSERT2(hio, done);
1699                 }
1700         }
1701         /* NOTREACHED */
1702         return (NULL);
1703 }
1704
1705 /*
1706  * Thread sends answer to the kernel.
1707  */
1708 static void *
1709 ggate_send_thread(void *arg)
1710 {
1711         struct hast_resource *res = arg;
1712         struct g_gate_ctl_io *ggio;
1713         struct hio *hio;
1714         unsigned int ii, ncomps;
1715
1716         ncomps = HAST_NCOMPONENTS;
1717
1718         for (;;) {
1719                 pjdlog_debug(2, "ggate_send: Taking request.");
1720                 QUEUE_TAKE2(hio, done);
1721                 pjdlog_debug(2, "ggate_send: (%p) Got request.", hio);
1722                 ggio = &hio->hio_ggio;
1723                 for (ii = 0; ii < ncomps; ii++) {
1724                         if (hio->hio_errors[ii] == 0) {
1725                                 /*
1726                                  * One successful request is enough to declare
1727                                  * success.
1728                                  */
1729                                 ggio->gctl_error = 0;
1730                                 break;
1731                         }
1732                 }
1733                 if (ii == ncomps) {
1734                         /*
1735                          * None of the requests were successful.
1736                          * Use the error from local component except the
1737                          * case when we did only remote request.
1738                          */
1739                         if (ggio->gctl_cmd == BIO_READ &&
1740                             res->hr_syncsrc == HAST_SYNCSRC_SECONDARY)
1741                                 ggio->gctl_error = hio->hio_errors[1];
1742                         else
1743                                 ggio->gctl_error = hio->hio_errors[0];
1744                 }
1745                 if (ggio->gctl_error == 0 && ggio->gctl_cmd == BIO_WRITE) {
1746                         mtx_lock(&res->hr_amp_lock);
1747                         if (activemap_write_complete(res->hr_amp,
1748                             ggio->gctl_offset, ggio->gctl_length)) {
1749                                 res->hr_stat_activemap_update++;
1750                                 (void)hast_activemap_flush(res);
1751                         }
1752                         mtx_unlock(&res->hr_amp_lock);
1753                 }
1754                 if (ggio->gctl_cmd == BIO_WRITE) {
1755                         /*
1756                          * Unlock range we locked.
1757                          */
1758                         mtx_lock(&range_lock);
1759                         rangelock_del(range_regular, ggio->gctl_offset,
1760                             ggio->gctl_length);
1761                         if (range_sync_wait)
1762                                 cv_signal(&range_sync_cond);
1763                         mtx_unlock(&range_lock);
1764                         if (!hio->hio_done)
1765                                 write_complete(res, hio);
1766                 } else {
1767                         if (ioctl(res->hr_ggatefd, G_GATE_CMD_DONE, ggio) == -1) {
1768                                 primary_exit(EX_OSERR,
1769                                     "G_GATE_CMD_DONE failed");
1770                         }
1771                 }
1772                 pjdlog_debug(2,
1773                     "ggate_send: (%p) Moving request to the free queue.", hio);
1774                 QUEUE_INSERT2(hio, free);
1775         }
1776         /* NOTREACHED */
1777         return (NULL);
1778 }
1779
1780 /*
1781  * Thread synchronize local and remote components.
1782  */
1783 static void *
1784 sync_thread(void *arg __unused)
1785 {
1786         struct hast_resource *res = arg;
1787         struct hio *hio;
1788         struct g_gate_ctl_io *ggio;
1789         struct timeval tstart, tend, tdiff;
1790         unsigned int ii, ncomp, ncomps;
1791         off_t offset, length, synced;
1792         bool dorewind;
1793         int syncext;
1794
1795         ncomps = HAST_NCOMPONENTS;
1796         dorewind = true;
1797         synced = 0;
1798         offset = -1;
1799
1800         for (;;) {
1801                 mtx_lock(&sync_lock);
1802                 if (offset >= 0 && !sync_inprogress) {
1803                         gettimeofday(&tend, NULL);
1804                         timersub(&tend, &tstart, &tdiff);
1805                         pjdlog_info("Synchronization interrupted after %#.0T. "
1806                             "%NB synchronized so far.", &tdiff,
1807                             (intmax_t)synced);
1808                         event_send(res, EVENT_SYNCINTR);
1809                 }
1810                 while (!sync_inprogress) {
1811                         dorewind = true;
1812                         synced = 0;
1813                         cv_wait(&sync_cond, &sync_lock);
1814                 }
1815                 mtx_unlock(&sync_lock);
1816                 /*
1817                  * Obtain offset at which we should synchronize.
1818                  * Rewind synchronization if needed.
1819                  */
1820                 mtx_lock(&res->hr_amp_lock);
1821                 if (dorewind)
1822                         activemap_sync_rewind(res->hr_amp);
1823                 offset = activemap_sync_offset(res->hr_amp, &length, &syncext);
1824                 if (syncext != -1) {
1825                         /*
1826                          * We synchronized entire syncext extent, we can mark
1827                          * it as clean now.
1828                          */
1829                         if (activemap_extent_complete(res->hr_amp, syncext))
1830                                 (void)hast_activemap_flush(res);
1831                 }
1832                 mtx_unlock(&res->hr_amp_lock);
1833                 if (dorewind) {
1834                         dorewind = false;
1835                         if (offset == -1)
1836                                 pjdlog_info("Nodes are in sync.");
1837                         else {
1838                                 pjdlog_info("Synchronization started. %NB to go.",
1839                                     (intmax_t)(res->hr_extentsize *
1840                                     activemap_ndirty(res->hr_amp)));
1841                                 event_send(res, EVENT_SYNCSTART);
1842                                 gettimeofday(&tstart, NULL);
1843                         }
1844                 }
1845                 if (offset == -1) {
1846                         sync_stop();
1847                         pjdlog_debug(1, "Nothing to synchronize.");
1848                         /*
1849                          * Synchronization complete, make both localcnt and
1850                          * remotecnt equal.
1851                          */
1852                         ncomp = 1;
1853                         rw_rlock(&hio_remote_lock[ncomp]);
1854                         if (ISCONNECTED(res, ncomp)) {
1855                                 if (synced > 0) {
1856                                         int64_t bps;
1857
1858                                         gettimeofday(&tend, NULL);
1859                                         timersub(&tend, &tstart, &tdiff);
1860                                         bps = (int64_t)((double)synced /
1861                                             ((double)tdiff.tv_sec +
1862                                             (double)tdiff.tv_usec / 1000000));
1863                                         pjdlog_info("Synchronization complete. "
1864                                             "%NB synchronized in %#.0lT (%NB/sec).",
1865                                             (intmax_t)synced, &tdiff,
1866                                             (intmax_t)bps);
1867                                         event_send(res, EVENT_SYNCDONE);
1868                                 }
1869                                 mtx_lock(&metadata_lock);
1870                                 res->hr_syncsrc = HAST_SYNCSRC_UNDEF;
1871                                 res->hr_primary_localcnt =
1872                                     res->hr_secondary_remotecnt;
1873                                 res->hr_primary_remotecnt =
1874                                     res->hr_secondary_localcnt;
1875                                 pjdlog_debug(1,
1876                                     "Setting localcnt to %ju and remotecnt to %ju.",
1877                                     (uintmax_t)res->hr_primary_localcnt,
1878                                     (uintmax_t)res->hr_primary_remotecnt);
1879                                 (void)metadata_write(res);
1880                                 mtx_unlock(&metadata_lock);
1881                         }
1882                         rw_unlock(&hio_remote_lock[ncomp]);
1883                         continue;
1884                 }
1885                 pjdlog_debug(2, "sync: Taking free request.");
1886                 QUEUE_TAKE2(hio, free);
1887                 pjdlog_debug(2, "sync: (%p) Got free request.", hio);
1888                 /*
1889                  * Lock the range we are going to synchronize. We don't want
1890                  * race where someone writes between our read and write.
1891                  */
1892                 for (;;) {
1893                         mtx_lock(&range_lock);
1894                         if (rangelock_islocked(range_regular, offset, length)) {
1895                                 pjdlog_debug(2,
1896                                     "sync: Range offset=%jd length=%jd locked.",
1897                                     (intmax_t)offset, (intmax_t)length);
1898                                 range_sync_wait = true;
1899                                 cv_wait(&range_sync_cond, &range_lock);
1900                                 range_sync_wait = false;
1901                                 mtx_unlock(&range_lock);
1902                                 continue;
1903                         }
1904                         if (rangelock_add(range_sync, offset, length) == -1) {
1905                                 mtx_unlock(&range_lock);
1906                                 pjdlog_debug(2,
1907                                     "sync: Range offset=%jd length=%jd is already locked, waiting.",
1908                                     (intmax_t)offset, (intmax_t)length);
1909                                 sleep(1);
1910                                 continue;
1911                         }
1912                         mtx_unlock(&range_lock);
1913                         break;
1914                 }
1915                 /*
1916                  * First read the data from synchronization source.
1917                  */
1918                 SYNCREQ(hio);
1919                 ggio = &hio->hio_ggio;
1920                 ggio->gctl_cmd = BIO_READ;
1921                 ggio->gctl_offset = offset;
1922                 ggio->gctl_length = length;
1923                 ggio->gctl_error = 0;
1924                 hio->hio_done = false;
1925                 hio->hio_replication = res->hr_replication;
1926                 for (ii = 0; ii < ncomps; ii++)
1927                         hio->hio_errors[ii] = EINVAL;
1928                 reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
1929                     hio);
1930                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
1931                     hio);
1932                 mtx_lock(&metadata_lock);
1933                 if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1934                         /*
1935                          * This range is up-to-date on local component,
1936                          * so handle request locally.
1937                          */
1938                          /* Local component is 0 for now. */
1939                         ncomp = 0;
1940                 } else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
1941                         PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
1942                         /*
1943                          * This range is out-of-date on local component,
1944                          * so send request to the remote node.
1945                          */
1946                          /* Remote component is 1 for now. */
1947                         ncomp = 1;
1948                 }
1949                 mtx_unlock(&metadata_lock);
1950                 refcount_init(&hio->hio_countdown, 1);
1951                 QUEUE_INSERT1(hio, send, ncomp);
1952
1953                 /*
1954                  * Let's wait for READ to finish.
1955                  */
1956                 mtx_lock(&sync_lock);
1957                 while (!ISSYNCREQDONE(hio))
1958                         cv_wait(&sync_cond, &sync_lock);
1959                 mtx_unlock(&sync_lock);
1960
1961                 if (hio->hio_errors[ncomp] != 0) {
1962                         pjdlog_error("Unable to read synchronization data: %s.",
1963                             strerror(hio->hio_errors[ncomp]));
1964                         goto free_queue;
1965                 }
1966
1967                 /*
1968                  * We read the data from synchronization source, now write it
1969                  * to synchronization target.
1970                  */
1971                 SYNCREQ(hio);
1972                 ggio->gctl_cmd = BIO_WRITE;
1973                 for (ii = 0; ii < ncomps; ii++)
1974                         hio->hio_errors[ii] = EINVAL;
1975                 reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
1976                     hio);
1977                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
1978                     hio);
1979                 mtx_lock(&metadata_lock);
1980                 if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1981                         /*
1982                          * This range is up-to-date on local component,
1983                          * so we update remote component.
1984                          */
1985                          /* Remote component is 1 for now. */
1986                         ncomp = 1;
1987                 } else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
1988                         PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
1989                         /*
1990                          * This range is out-of-date on local component,
1991                          * so we update it.
1992                          */
1993                          /* Local component is 0 for now. */
1994                         ncomp = 0;
1995                 }
1996                 mtx_unlock(&metadata_lock);
1997
1998                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
1999                     hio);
2000                 refcount_init(&hio->hio_countdown, 1);
2001                 QUEUE_INSERT1(hio, send, ncomp);
2002
2003                 /*
2004                  * Let's wait for WRITE to finish.
2005                  */
2006                 mtx_lock(&sync_lock);
2007                 while (!ISSYNCREQDONE(hio))
2008                         cv_wait(&sync_cond, &sync_lock);
2009                 mtx_unlock(&sync_lock);
2010
2011                 if (hio->hio_errors[ncomp] != 0) {
2012                         pjdlog_error("Unable to write synchronization data: %s.",
2013                             strerror(hio->hio_errors[ncomp]));
2014                         goto free_queue;
2015                 }
2016
2017                 synced += length;
2018 free_queue:
2019                 mtx_lock(&range_lock);
2020                 rangelock_del(range_sync, offset, length);
2021                 if (range_regular_wait)
2022                         cv_signal(&range_regular_cond);
2023                 mtx_unlock(&range_lock);
2024                 pjdlog_debug(2, "sync: (%p) Moving request to the free queue.",
2025                     hio);
2026                 QUEUE_INSERT2(hio, free);
2027         }
2028         /* NOTREACHED */
2029         return (NULL);
2030 }
2031
2032 void
2033 primary_config_reload(struct hast_resource *res, struct nv *nv)
2034 {
2035         unsigned int ii, ncomps;
2036         int modified, vint;
2037         const char *vstr;
2038
2039         pjdlog_info("Reloading configuration...");
2040
2041         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
2042         PJDLOG_ASSERT(gres == res);
2043         nv_assert(nv, "remoteaddr");
2044         nv_assert(nv, "sourceaddr");
2045         nv_assert(nv, "replication");
2046         nv_assert(nv, "checksum");
2047         nv_assert(nv, "compression");
2048         nv_assert(nv, "timeout");
2049         nv_assert(nv, "exec");
2050         nv_assert(nv, "metaflush");
2051
2052         ncomps = HAST_NCOMPONENTS;
2053
2054 #define MODIFIED_REMOTEADDR     0x01
2055 #define MODIFIED_SOURCEADDR     0x02
2056 #define MODIFIED_REPLICATION    0x04
2057 #define MODIFIED_CHECKSUM       0x08
2058 #define MODIFIED_COMPRESSION    0x10
2059 #define MODIFIED_TIMEOUT        0x20
2060 #define MODIFIED_EXEC           0x40
2061 #define MODIFIED_METAFLUSH      0x80
2062         modified = 0;
2063
2064         vstr = nv_get_string(nv, "remoteaddr");
2065         if (strcmp(gres->hr_remoteaddr, vstr) != 0) {
2066                 /*
2067                  * Don't copy res->hr_remoteaddr to gres just yet.
2068                  * We want remote_close() to log disconnect from the old
2069                  * addresses, not from the new ones.
2070                  */
2071                 modified |= MODIFIED_REMOTEADDR;
2072         }
2073         vstr = nv_get_string(nv, "sourceaddr");
2074         if (strcmp(gres->hr_sourceaddr, vstr) != 0) {
2075                 strlcpy(gres->hr_sourceaddr, vstr, sizeof(gres->hr_sourceaddr));
2076                 modified |= MODIFIED_SOURCEADDR;
2077         }
2078         vint = nv_get_int32(nv, "replication");
2079         if (gres->hr_replication != vint) {
2080                 gres->hr_replication = vint;
2081                 modified |= MODIFIED_REPLICATION;
2082         }
2083         vint = nv_get_int32(nv, "checksum");
2084         if (gres->hr_checksum != vint) {
2085                 gres->hr_checksum = vint;
2086                 modified |= MODIFIED_CHECKSUM;
2087         }
2088         vint = nv_get_int32(nv, "compression");
2089         if (gres->hr_compression != vint) {
2090                 gres->hr_compression = vint;
2091                 modified |= MODIFIED_COMPRESSION;
2092         }
2093         vint = nv_get_int32(nv, "timeout");
2094         if (gres->hr_timeout != vint) {
2095                 gres->hr_timeout = vint;
2096                 modified |= MODIFIED_TIMEOUT;
2097         }
2098         vstr = nv_get_string(nv, "exec");
2099         if (strcmp(gres->hr_exec, vstr) != 0) {
2100                 strlcpy(gres->hr_exec, vstr, sizeof(gres->hr_exec));
2101                 modified |= MODIFIED_EXEC;
2102         }
2103         vint = nv_get_int32(nv, "metaflush");
2104         if (gres->hr_metaflush != vint) {
2105                 gres->hr_metaflush = vint;
2106                 modified |= MODIFIED_METAFLUSH;
2107         }
2108
2109         /*
2110          * Change timeout for connected sockets.
2111          * Don't bother if we need to reconnect.
2112          */
2113         if ((modified & MODIFIED_TIMEOUT) != 0 &&
2114             (modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR)) == 0) {
2115                 for (ii = 0; ii < ncomps; ii++) {
2116                         if (!ISREMOTE(ii))
2117                                 continue;
2118                         rw_rlock(&hio_remote_lock[ii]);
2119                         if (!ISCONNECTED(gres, ii)) {
2120                                 rw_unlock(&hio_remote_lock[ii]);
2121                                 continue;
2122                         }
2123                         rw_unlock(&hio_remote_lock[ii]);
2124                         if (proto_timeout(gres->hr_remotein,
2125                             gres->hr_timeout) == -1) {
2126                                 pjdlog_errno(LOG_WARNING,
2127                                     "Unable to set connection timeout");
2128                         }
2129                         if (proto_timeout(gres->hr_remoteout,
2130                             gres->hr_timeout) == -1) {
2131                                 pjdlog_errno(LOG_WARNING,
2132                                     "Unable to set connection timeout");
2133                         }
2134                 }
2135         }
2136         if ((modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR)) != 0) {
2137                 for (ii = 0; ii < ncomps; ii++) {
2138                         if (!ISREMOTE(ii))
2139                                 continue;
2140                         remote_close(gres, ii);
2141                 }
2142                 if (modified & MODIFIED_REMOTEADDR) {
2143                         vstr = nv_get_string(nv, "remoteaddr");
2144                         strlcpy(gres->hr_remoteaddr, vstr,
2145                             sizeof(gres->hr_remoteaddr));
2146                 }
2147         }
2148 #undef  MODIFIED_REMOTEADDR
2149 #undef  MODIFIED_SOURCEADDR
2150 #undef  MODIFIED_REPLICATION
2151 #undef  MODIFIED_CHECKSUM
2152 #undef  MODIFIED_COMPRESSION
2153 #undef  MODIFIED_TIMEOUT
2154 #undef  MODIFIED_EXEC
2155 #undef  MODIFIED_METAFLUSH
2156
2157         pjdlog_info("Configuration reloaded successfully.");
2158 }
2159
2160 static void
2161 guard_one(struct hast_resource *res, unsigned int ncomp)
2162 {
2163         struct proto_conn *in, *out;
2164
2165         if (!ISREMOTE(ncomp))
2166                 return;
2167
2168         rw_rlock(&hio_remote_lock[ncomp]);
2169
2170         if (!real_remote(res)) {
2171                 rw_unlock(&hio_remote_lock[ncomp]);
2172                 return;
2173         }
2174
2175         if (ISCONNECTED(res, ncomp)) {
2176                 PJDLOG_ASSERT(res->hr_remotein != NULL);
2177                 PJDLOG_ASSERT(res->hr_remoteout != NULL);
2178                 rw_unlock(&hio_remote_lock[ncomp]);
2179                 pjdlog_debug(2, "remote_guard: Connection to %s is ok.",
2180                     res->hr_remoteaddr);
2181                 return;
2182         }
2183
2184         PJDLOG_ASSERT(res->hr_remotein == NULL);
2185         PJDLOG_ASSERT(res->hr_remoteout == NULL);
2186         /*
2187          * Upgrade the lock. It doesn't have to be atomic as no other thread
2188          * can change connection status from disconnected to connected.
2189          */
2190         rw_unlock(&hio_remote_lock[ncomp]);
2191         pjdlog_debug(2, "remote_guard: Reconnecting to %s.",
2192             res->hr_remoteaddr);
2193         in = out = NULL;
2194         if (init_remote(res, &in, &out) == 0) {
2195                 rw_wlock(&hio_remote_lock[ncomp]);
2196                 PJDLOG_ASSERT(res->hr_remotein == NULL);
2197                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
2198                 PJDLOG_ASSERT(in != NULL && out != NULL);
2199                 res->hr_remotein = in;
2200                 res->hr_remoteout = out;
2201                 rw_unlock(&hio_remote_lock[ncomp]);
2202                 pjdlog_info("Successfully reconnected to %s.",
2203                     res->hr_remoteaddr);
2204                 sync_start();
2205         } else {
2206                 /* Both connections should be NULL. */
2207                 PJDLOG_ASSERT(res->hr_remotein == NULL);
2208                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
2209                 PJDLOG_ASSERT(in == NULL && out == NULL);
2210                 pjdlog_debug(2, "remote_guard: Reconnect to %s failed.",
2211                     res->hr_remoteaddr);
2212         }
2213 }
2214
2215 /*
2216  * Thread guards remote connections and reconnects when needed, handles
2217  * signals, etc.
2218  */
2219 static void *
2220 guard_thread(void *arg)
2221 {
2222         struct hast_resource *res = arg;
2223         unsigned int ii, ncomps;
2224         struct timespec timeout;
2225         time_t lastcheck, now;
2226         sigset_t mask;
2227         int signo;
2228
2229         ncomps = HAST_NCOMPONENTS;
2230         lastcheck = time(NULL);
2231
2232         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
2233         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
2234         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
2235
2236         timeout.tv_sec = HAST_KEEPALIVE;
2237         timeout.tv_nsec = 0;
2238         signo = -1;
2239
2240         for (;;) {
2241                 switch (signo) {
2242                 case SIGINT:
2243                 case SIGTERM:
2244                         sigexit_received = true;
2245                         primary_exitx(EX_OK,
2246                             "Termination signal received, exiting.");
2247                         break;
2248                 default:
2249                         break;
2250                 }
2251
2252                 /*
2253                  * Don't check connections until we fully started,
2254                  * as we may still be looping, waiting for remote node
2255                  * to switch from primary to secondary.
2256                  */
2257                 if (fullystarted) {
2258                         pjdlog_debug(2, "remote_guard: Checking connections.");
2259                         now = time(NULL);
2260                         if (lastcheck + HAST_KEEPALIVE <= now) {
2261                                 for (ii = 0; ii < ncomps; ii++)
2262                                         guard_one(res, ii);
2263                                 lastcheck = now;
2264                         }
2265                 }
2266                 signo = sigtimedwait(&mask, NULL, &timeout);
2267         }
2268         /* NOTREACHED */
2269         return (NULL);
2270 }