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) < 0) {
 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) < 0)
 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) < 0)
 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) < 0) {
 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) < 0)
 476                 primary_exit(EX_TEMPFAIL, "Unable to create regular range lock");
 477         cv_init(&range_sync_cond);
 478         if (rangelock_init(&range_sync) < 0)
 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) < 0)
 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)) < 0) {
 515                 primary_exit(EX_TEMPFAIL,
 516                     "Unable to send connection request to parent");
 517         }
 518         if (proto_recv(res->hr_conn, &val, sizeof(val)) < 0) {
 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) < 0) {
 529                 primary_exit(EX_TEMPFAIL,
 530                     "Unable to receive connection from parent");
 531         }
 532         if (proto_connect_wait(conn, res->hr_timeout) < 0) {
 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) < 0)
 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) < 0) {
 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) < 0) {
 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) < 0) {
 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) < 0) {
 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) < 0) {
 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 < 0)
 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) < 0) {
 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) < 0) {
 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) < 0) {
 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 < 0) {
 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 begining.
 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         int len;
 994
 995         va_start(ap, fmt);
 996         len = vsnprintf(msg, sizeof(msg), fmt, ap);
 997         va_end(ap);
 998         if ((size_t)len < sizeof(msg)) {
 999                 switch (ggio->gctl_cmd) {
1000                 case BIO_READ:
1001                         (void)snprintf(msg + len, sizeof(msg) - len,
1002                             "READ(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
1003                             (uintmax_t)ggio->gctl_length);
1004                         break;
1005                 case BIO_DELETE:
1006                         (void)snprintf(msg + len, sizeof(msg) - len,
1007                             "DELETE(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
1008                             (uintmax_t)ggio->gctl_length);
1009                         break;
1010                 case BIO_FLUSH:
1011                         (void)snprintf(msg + len, sizeof(msg) - len, "FLUSH.");
1012                         break;
1013                 case BIO_WRITE:
1014                         (void)snprintf(msg + len, sizeof(msg) - len,
1015                             "WRITE(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
1016                             (uintmax_t)ggio->gctl_length);
1017                         break;
1018                 default:
1019                         (void)snprintf(msg + len, sizeof(msg) - len,
1020                             "UNKNOWN(%u).", (unsigned int)ggio->gctl_cmd);
1021                         break;
1022                 }
1023         }
1024         pjdlog_common(loglevel, debuglevel, -1, "%s", msg);
1025 }
1026
1027 static void
1028 remote_close(struct hast_resource *res, int ncomp)
1029 {
1030
1031         rw_wlock(&hio_remote_lock[ncomp]);
1032         /*
1033          * Check for a race between dropping rlock and acquiring wlock -
1034          * another thread can close connection in-between.
1035          */
1036         if (!ISCONNECTED(res, ncomp)) {
1037                 PJDLOG_ASSERT(res->hr_remotein == NULL);
1038                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
1039                 rw_unlock(&hio_remote_lock[ncomp]);
1040                 return;
1041         }
1042
1043         PJDLOG_ASSERT(res->hr_remotein != NULL);
1044         PJDLOG_ASSERT(res->hr_remoteout != NULL);
1045
1046         pjdlog_debug(2, "Closing incoming connection to %s.",
1047             res->hr_remoteaddr);
1048         proto_close(res->hr_remotein);
1049         res->hr_remotein = NULL;
1050         pjdlog_debug(2, "Closing outgoing connection to %s.",
1051             res->hr_remoteaddr);
1052         proto_close(res->hr_remoteout);
1053         res->hr_remoteout = NULL;
1054
1055         rw_unlock(&hio_remote_lock[ncomp]);
1056
1057         pjdlog_warning("Disconnected from %s.", res->hr_remoteaddr);
1058
1059         /*
1060          * Stop synchronization if in-progress.
1061          */
1062         sync_stop();
1063
1064         event_send(res, EVENT_DISCONNECT);
1065 }
1066
1067 /*
1068  * Acknowledge write completion to the kernel, but don't update activemap yet.
1069  */
1070 static void
1071 write_complete(struct hast_resource *res, struct hio *hio)
1072 {
1073         struct g_gate_ctl_io *ggio;
1074         unsigned int ncomp;
1075
1076         PJDLOG_ASSERT(!hio->hio_done);
1077
1078         ggio = &hio->hio_ggio;
1079         PJDLOG_ASSERT(ggio->gctl_cmd == BIO_WRITE);
1080
1081         /*
1082          * Bump local count if this is first write after
1083          * connection failure with remote node.
1084          */
1085         ncomp = 1;
1086         rw_rlock(&hio_remote_lock[ncomp]);
1087         if (!ISCONNECTED(res, ncomp)) {
1088                 mtx_lock(&metadata_lock);
1089                 if (res->hr_primary_localcnt == res->hr_secondary_remotecnt) {
1090                         res->hr_primary_localcnt++;
1091                         pjdlog_debug(1, "Increasing localcnt to %ju.",
1092                             (uintmax_t)res->hr_primary_localcnt);
1093                         (void)metadata_write(res);
1094                 }
1095                 mtx_unlock(&metadata_lock);
1096         }
1097         rw_unlock(&hio_remote_lock[ncomp]);
1098         if (ioctl(res->hr_ggatefd, G_GATE_CMD_DONE, ggio) < 0)
1099                 primary_exit(EX_OSERR, "G_GATE_CMD_DONE failed");
1100         hio->hio_done = true;
1101 }
1102
1103 /*
1104  * Thread receives ggate I/O requests from the kernel and passes them to
1105  * appropriate threads:
1106  * WRITE - always goes to both local_send and remote_send threads
1107  * READ (when the block is up-to-date on local component) -
1108  *      only local_send thread
1109  * READ (when the block isn't up-to-date on local component) -
1110  *      only remote_send thread
1111  * DELETE - always goes to both local_send and remote_send threads
1112  * FLUSH - always goes to both local_send and remote_send threads
1113  */
1114 static void *
1115 ggate_recv_thread(void *arg)
1116 {
1117         struct hast_resource *res = arg;
1118         struct g_gate_ctl_io *ggio;
1119         struct hio *hio;
1120         unsigned int ii, ncomp, ncomps;
1121         int error;
1122
1123         for (;;) {
1124                 pjdlog_debug(2, "ggate_recv: Taking free request.");
1125                 QUEUE_TAKE2(hio, free);
1126                 pjdlog_debug(2, "ggate_recv: (%p) Got free request.", hio);
1127                 ggio = &hio->hio_ggio;
1128                 ggio->gctl_unit = res->hr_ggateunit;
1129                 ggio->gctl_length = MAXPHYS;
1130                 ggio->gctl_error = 0;
1131                 hio->hio_done = false;
1132                 hio->hio_replication = res->hr_replication;
1133                 pjdlog_debug(2,
1134                     "ggate_recv: (%p) Waiting for request from the kernel.",
1135                     hio);
1136                 if (ioctl(res->hr_ggatefd, G_GATE_CMD_START, ggio) < 0) {
1137                         if (sigexit_received)
1138                                 pthread_exit(NULL);
1139                         primary_exit(EX_OSERR, "G_GATE_CMD_START failed");
1140                 }
1141                 error = ggio->gctl_error;
1142                 switch (error) {
1143                 case 0:
1144                         break;
1145                 case ECANCELED:
1146                         /* Exit gracefully. */
1147                         if (!sigexit_received) {
1148                                 pjdlog_debug(2,
1149                                     "ggate_recv: (%p) Received cancel from the kernel.",
1150                                     hio);
1151                                 pjdlog_info("Received cancel from the kernel, exiting.");
1152                         }
1153                         pthread_exit(NULL);
1154                 case ENOMEM:
1155                         /*
1156                          * Buffer too small? Impossible, we allocate MAXPHYS
1157                          * bytes - request can't be bigger than that.
1158                          */
1159                         /* FALLTHROUGH */
1160                 case ENXIO:
1161                 default:
1162                         primary_exitx(EX_OSERR, "G_GATE_CMD_START failed: %s.",
1163                             strerror(error));
1164                 }
1165
1166                 ncomp = 0;
1167                 ncomps = HAST_NCOMPONENTS;
1168
1169                 for (ii = 0; ii < ncomps; ii++)
1170                         hio->hio_errors[ii] = EINVAL;
1171                 reqlog(LOG_DEBUG, 2, ggio,
1172                     "ggate_recv: (%p) Request received from the kernel: ",
1173                     hio);
1174
1175                 /*
1176                  * Inform all components about new write request.
1177                  * For read request prefer local component unless the given
1178                  * range is out-of-date, then use remote component.
1179                  */
1180                 switch (ggio->gctl_cmd) {
1181                 case BIO_READ:
1182                         res->hr_stat_read++;
1183                         ncomps = 1;
1184                         mtx_lock(&metadata_lock);
1185                         if (res->hr_syncsrc == HAST_SYNCSRC_UNDEF ||
1186                             res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1187                                 /*
1188                                  * This range is up-to-date on local component,
1189                                  * so handle request locally.
1190                                  */
1191                                  /* Local component is 0 for now. */
1192                                 ncomp = 0;
1193                         } else /* if (res->hr_syncsrc ==
1194                             HAST_SYNCSRC_SECONDARY) */ {
1195                                 PJDLOG_ASSERT(res->hr_syncsrc ==
1196                                     HAST_SYNCSRC_SECONDARY);
1197                                 /*
1198                                  * This range is out-of-date on local component,
1199                                  * so send request to the remote node.
1200                                  */
1201                                  /* Remote component is 1 for now. */
1202                                 ncomp = 1;
1203                         }
1204                         mtx_unlock(&metadata_lock);
1205                         break;
1206                 case BIO_WRITE:
1207                         res->hr_stat_write++;
1208                         if (res->hr_resuid == 0 &&
1209                             res->hr_primary_localcnt == 0) {
1210                                 /* This is first write. */
1211                                 res->hr_primary_localcnt = 1;
1212                         }
1213                         for (;;) {
1214                                 mtx_lock(&range_lock);
1215                                 if (rangelock_islocked(range_sync,
1216                                     ggio->gctl_offset, ggio->gctl_length)) {
1217                                         pjdlog_debug(2,
1218                                             "regular: Range offset=%jd length=%zu locked.",
1219                                             (intmax_t)ggio->gctl_offset,
1220                                             (size_t)ggio->gctl_length);
1221                                         range_regular_wait = true;
1222                                         cv_wait(&range_regular_cond, &range_lock);
1223                                         range_regular_wait = false;
1224                                         mtx_unlock(&range_lock);
1225                                         continue;
1226                                 }
1227                                 if (rangelock_add(range_regular,
1228                                     ggio->gctl_offset, ggio->gctl_length) < 0) {
1229                                         mtx_unlock(&range_lock);
1230                                         pjdlog_debug(2,
1231                                             "regular: Range offset=%jd length=%zu is already locked, waiting.",
1232                                             (intmax_t)ggio->gctl_offset,
1233                                             (size_t)ggio->gctl_length);
1234                                         sleep(1);
1235                                         continue;
1236                                 }
1237                                 mtx_unlock(&range_lock);
1238                                 break;
1239                         }
1240                         mtx_lock(&res->hr_amp_lock);
1241                         if (activemap_write_start(res->hr_amp,
1242                             ggio->gctl_offset, ggio->gctl_length)) {
1243                                 res->hr_stat_activemap_update++;
1244                                 (void)hast_activemap_flush(res);
1245                         }
1246                         mtx_unlock(&res->hr_amp_lock);
1247                         break;
1248                 case BIO_DELETE:
1249                         res->hr_stat_delete++;
1250                         break;
1251                 case BIO_FLUSH:
1252                         res->hr_stat_flush++;
1253                         break;
1254                 }
1255                 pjdlog_debug(2,
1256                     "ggate_recv: (%p) Moving request to the send queues.", hio);
1257                 refcount_init(&hio->hio_countdown, ncomps);
1258                 for (ii = ncomp; ii < ncomps; ii++)
1259                         QUEUE_INSERT1(hio, send, ii);
1260         }
1261         /* NOTREACHED */
1262         return (NULL);
1263 }
1264
1265 /*
1266  * Thread reads from or writes to local component.
1267  * If local read fails, it redirects it to remote_send thread.
1268  */
1269 static void *
1270 local_send_thread(void *arg)
1271 {
1272         struct hast_resource *res = arg;
1273         struct g_gate_ctl_io *ggio;
1274         struct hio *hio;
1275         unsigned int ncomp, rncomp;
1276         ssize_t ret;
1277
1278         /* Local component is 0 for now. */
1279         ncomp = 0;
1280         /* Remote component is 1 for now. */
1281         rncomp = 1;
1282
1283         for (;;) {
1284                 pjdlog_debug(2, "local_send: Taking request.");
1285                 QUEUE_TAKE1(hio, send, ncomp, 0);
1286                 pjdlog_debug(2, "local_send: (%p) Got request.", hio);
1287                 ggio = &hio->hio_ggio;
1288                 switch (ggio->gctl_cmd) {
1289                 case BIO_READ:
1290                         ret = pread(res->hr_localfd, ggio->gctl_data,
1291                             ggio->gctl_length,
1292                             ggio->gctl_offset + res->hr_localoff);
1293                         if (ret == ggio->gctl_length)
1294                                 hio->hio_errors[ncomp] = 0;
1295                         else if (!ISSYNCREQ(hio)) {
1296                                 /*
1297                                  * If READ failed, try to read from remote node.
1298                                  */
1299                                 if (ret < 0) {
1300                                         reqlog(LOG_WARNING, 0, ggio,
1301                                             "Local request failed (%s), trying remote node. ",
1302                                             strerror(errno));
1303                                 } else if (ret != ggio->gctl_length) {
1304                                         reqlog(LOG_WARNING, 0, ggio,
1305                                             "Local request failed (%zd != %jd), trying remote node. ",
1306                                             ret, (intmax_t)ggio->gctl_length);
1307                                 }
1308                                 QUEUE_INSERT1(hio, send, rncomp);
1309                                 continue;
1310                         }
1311                         break;
1312                 case BIO_WRITE:
1313                         ret = pwrite(res->hr_localfd, ggio->gctl_data,
1314                             ggio->gctl_length,
1315                             ggio->gctl_offset + res->hr_localoff);
1316                         if (ret < 0) {
1317                                 hio->hio_errors[ncomp] = errno;
1318                                 reqlog(LOG_WARNING, 0, ggio,
1319                                     "Local request failed (%s): ",
1320                                     strerror(errno));
1321                         } else if (ret != ggio->gctl_length) {
1322                                 hio->hio_errors[ncomp] = EIO;
1323                                 reqlog(LOG_WARNING, 0, ggio,
1324                                     "Local request failed (%zd != %jd): ",
1325                                     ret, (intmax_t)ggio->gctl_length);
1326                         } else {
1327                                 hio->hio_errors[ncomp] = 0;
1328                                 if (hio->hio_replication ==
1329                                     HAST_REPLICATION_ASYNC) {
1330                                         ggio->gctl_error = 0;
1331                                         write_complete(res, hio);
1332                                 }
1333                         }
1334                         break;
1335                 case BIO_DELETE:
1336                         ret = g_delete(res->hr_localfd,
1337                             ggio->gctl_offset + res->hr_localoff,
1338                             ggio->gctl_length);
1339                         if (ret < 0) {
1340                                 hio->hio_errors[ncomp] = errno;
1341                                 reqlog(LOG_WARNING, 0, ggio,
1342                                     "Local request failed (%s): ",
1343                                     strerror(errno));
1344                         } else {
1345                                 hio->hio_errors[ncomp] = 0;
1346                         }
1347                         break;
1348                 case BIO_FLUSH:
1349                         if (!res->hr_localflush) {
1350                                 ret = -1;
1351                                 errno = EOPNOTSUPP;
1352                                 break;
1353                         }
1354                         ret = g_flush(res->hr_localfd);
1355                         if (ret < 0) {
1356                                 if (errno == EOPNOTSUPP)
1357                                         res->hr_localflush = false;
1358                                 hio->hio_errors[ncomp] = errno;
1359                                 reqlog(LOG_WARNING, 0, ggio,
1360                                     "Local request failed (%s): ",
1361                                     strerror(errno));
1362                         } else {
1363                                 hio->hio_errors[ncomp] = 0;
1364                         }
1365                         break;
1366                 }
1367                 if (!refcount_release(&hio->hio_countdown))
1368                         continue;
1369                 if (ISSYNCREQ(hio)) {
1370                         mtx_lock(&sync_lock);
1371                         SYNCREQDONE(hio);
1372                         mtx_unlock(&sync_lock);
1373                         cv_signal(&sync_cond);
1374                 } else {
1375                         pjdlog_debug(2,
1376                             "local_send: (%p) Moving request to the done queue.",
1377                             hio);
1378                         QUEUE_INSERT2(hio, done);
1379                 }
1380         }
1381         /* NOTREACHED */
1382         return (NULL);
1383 }
1384
1385 static void
1386 keepalive_send(struct hast_resource *res, unsigned int ncomp)
1387 {
1388         struct nv *nv;
1389
1390         rw_rlock(&hio_remote_lock[ncomp]);
1391
1392         if (!ISCONNECTED(res, ncomp)) {
1393                 rw_unlock(&hio_remote_lock[ncomp]);
1394                 return;
1395         }
1396
1397         PJDLOG_ASSERT(res->hr_remotein != NULL);
1398         PJDLOG_ASSERT(res->hr_remoteout != NULL);
1399
1400         nv = nv_alloc();
1401         nv_add_uint8(nv, HIO_KEEPALIVE, "cmd");
1402         if (nv_error(nv) != 0) {
1403                 rw_unlock(&hio_remote_lock[ncomp]);
1404                 nv_free(nv);
1405                 pjdlog_debug(1,
1406                     "keepalive_send: Unable to prepare header to send.");
1407                 return;
1408         }
1409         if (hast_proto_send(res, res->hr_remoteout, nv, NULL, 0) < 0) {
1410                 rw_unlock(&hio_remote_lock[ncomp]);
1411                 pjdlog_common(LOG_DEBUG, 1, errno,
1412                     "keepalive_send: Unable to send request");
1413                 nv_free(nv);
1414                 remote_close(res, ncomp);
1415                 return;
1416         }
1417
1418         rw_unlock(&hio_remote_lock[ncomp]);
1419         nv_free(nv);
1420         pjdlog_debug(2, "keepalive_send: Request sent.");
1421 }
1422
1423 /*
1424  * Thread sends request to secondary node.
1425  */
1426 static void *
1427 remote_send_thread(void *arg)
1428 {
1429         struct hast_resource *res = arg;
1430         struct g_gate_ctl_io *ggio;
1431         time_t lastcheck, now;
1432         struct hio *hio;
1433         struct nv *nv;
1434         unsigned int ncomp;
1435         bool wakeup;
1436         uint64_t offset, length;
1437         uint8_t cmd;
1438         void *data;
1439
1440         /* Remote component is 1 for now. */
1441         ncomp = 1;
1442         lastcheck = time(NULL);
1443
1444         for (;;) {
1445                 pjdlog_debug(2, "remote_send: Taking request.");
1446                 QUEUE_TAKE1(hio, send, ncomp, HAST_KEEPALIVE);
1447                 if (hio == NULL) {
1448                         now = time(NULL);
1449                         if (lastcheck + HAST_KEEPALIVE <= now) {
1450                                 keepalive_send(res, ncomp);
1451                                 lastcheck = now;
1452                         }
1453                         continue;
1454                 }
1455                 pjdlog_debug(2, "remote_send: (%p) Got request.", hio);
1456                 ggio = &hio->hio_ggio;
1457                 switch (ggio->gctl_cmd) {
1458                 case BIO_READ:
1459                         cmd = HIO_READ;
1460                         data = NULL;
1461                         offset = ggio->gctl_offset;
1462                         length = ggio->gctl_length;
1463                         break;
1464                 case BIO_WRITE:
1465                         cmd = HIO_WRITE;
1466                         data = ggio->gctl_data;
1467                         offset = ggio->gctl_offset;
1468                         length = ggio->gctl_length;
1469                         break;
1470                 case BIO_DELETE:
1471                         cmd = HIO_DELETE;
1472                         data = NULL;
1473                         offset = ggio->gctl_offset;
1474                         length = ggio->gctl_length;
1475                         break;
1476                 case BIO_FLUSH:
1477                         cmd = HIO_FLUSH;
1478                         data = NULL;
1479                         offset = 0;
1480                         length = 0;
1481                         break;
1482                 default:
1483                         PJDLOG_ABORT("invalid condition");
1484                 }
1485                 nv = nv_alloc();
1486                 nv_add_uint8(nv, cmd, "cmd");
1487                 nv_add_uint64(nv, (uint64_t)ggio->gctl_seq, "seq");
1488                 nv_add_uint64(nv, offset, "offset");
1489                 nv_add_uint64(nv, length, "length");
1490                 if (nv_error(nv) != 0) {
1491                         hio->hio_errors[ncomp] = nv_error(nv);
1492                         pjdlog_debug(2,
1493                             "remote_send: (%p) Unable to prepare header to send.",
1494                             hio);
1495                         reqlog(LOG_ERR, 0, ggio,
1496                             "Unable to prepare header to send (%s): ",
1497                             strerror(nv_error(nv)));
1498                         /* Move failed request immediately to the done queue. */
1499                         goto done_queue;
1500                 }
1501                 /*
1502                  * Protect connection from disappearing.
1503                  */
1504                 rw_rlock(&hio_remote_lock[ncomp]);
1505                 if (!ISCONNECTED(res, ncomp)) {
1506                         rw_unlock(&hio_remote_lock[ncomp]);
1507                         hio->hio_errors[ncomp] = ENOTCONN;
1508                         goto done_queue;
1509                 }
1510                 /*
1511                  * Move the request to recv queue before sending it, because
1512                  * in different order we can get reply before we move request
1513                  * to recv queue.
1514                  */
1515                 pjdlog_debug(2,
1516                     "remote_send: (%p) Moving request to the recv queue.",
1517                     hio);
1518                 mtx_lock(&hio_recv_list_lock[ncomp]);
1519                 wakeup = TAILQ_EMPTY(&hio_recv_list[ncomp]);
1520                 TAILQ_INSERT_TAIL(&hio_recv_list[ncomp], hio, hio_next[ncomp]);
1521                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1522                 if (hast_proto_send(res, res->hr_remoteout, nv, data,
1523                     data != NULL ? length : 0) < 0) {
1524                         hio->hio_errors[ncomp] = errno;
1525                         rw_unlock(&hio_remote_lock[ncomp]);
1526                         pjdlog_debug(2,
1527                             "remote_send: (%p) Unable to send request.", hio);
1528                         reqlog(LOG_ERR, 0, ggio,
1529                             "Unable to send request (%s): ",
1530                             strerror(hio->hio_errors[ncomp]));
1531                         remote_close(res, ncomp);
1532                         /*
1533                          * Take request back from the receive queue and move
1534                          * it immediately to the done queue.
1535                          */
1536                         mtx_lock(&hio_recv_list_lock[ncomp]);
1537                         TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1538                             hio_next[ncomp]);
1539                         mtx_unlock(&hio_recv_list_lock[ncomp]);
1540                         goto done_queue;
1541                 }
1542                 rw_unlock(&hio_remote_lock[ncomp]);
1543                 nv_free(nv);
1544                 if (wakeup)
1545                         cv_signal(&hio_recv_list_cond[ncomp]);
1546                 continue;
1547 done_queue:
1548                 nv_free(nv);
1549                 if (ISSYNCREQ(hio)) {
1550                         if (!refcount_release(&hio->hio_countdown))
1551                                 continue;
1552                         mtx_lock(&sync_lock);
1553                         SYNCREQDONE(hio);
1554                         mtx_unlock(&sync_lock);
1555                         cv_signal(&sync_cond);
1556                         continue;
1557                 }
1558                 if (ggio->gctl_cmd == BIO_WRITE) {
1559                         mtx_lock(&res->hr_amp_lock);
1560                         if (activemap_need_sync(res->hr_amp, ggio->gctl_offset,
1561                             ggio->gctl_length)) {
1562                                 (void)hast_activemap_flush(res);
1563                         }
1564                         mtx_unlock(&res->hr_amp_lock);
1565                 }
1566                 if (!refcount_release(&hio->hio_countdown))
1567                         continue;
1568                 pjdlog_debug(2,
1569                     "remote_send: (%p) Moving request to the done queue.",
1570                     hio);
1571                 QUEUE_INSERT2(hio, done);
1572         }
1573         /* NOTREACHED */
1574         return (NULL);
1575 }
1576
1577 /*
1578  * Thread receives answer from secondary node and passes it to ggate_send
1579  * thread.
1580  */
1581 static void *
1582 remote_recv_thread(void *arg)
1583 {
1584         struct hast_resource *res = arg;
1585         struct g_gate_ctl_io *ggio;
1586         struct hio *hio;
1587         struct nv *nv;
1588         unsigned int ncomp;
1589         uint64_t seq;
1590         int error;
1591
1592         /* Remote component is 1 for now. */
1593         ncomp = 1;
1594
1595         for (;;) {
1596                 /* Wait until there is anything to receive. */
1597                 mtx_lock(&hio_recv_list_lock[ncomp]);
1598                 while (TAILQ_EMPTY(&hio_recv_list[ncomp])) {
1599                         pjdlog_debug(2, "remote_recv: No requests, waiting.");
1600                         cv_wait(&hio_recv_list_cond[ncomp],
1601                             &hio_recv_list_lock[ncomp]);
1602                 }
1603                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1604
1605                 rw_rlock(&hio_remote_lock[ncomp]);
1606                 if (!ISCONNECTED(res, ncomp)) {
1607                         rw_unlock(&hio_remote_lock[ncomp]);
1608                         /*
1609                          * Connection is dead, so move all pending requests to
1610                          * the done queue (one-by-one).
1611                          */
1612                         mtx_lock(&hio_recv_list_lock[ncomp]);
1613                         hio = TAILQ_FIRST(&hio_recv_list[ncomp]);
1614                         PJDLOG_ASSERT(hio != NULL);
1615                         TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1616                             hio_next[ncomp]);
1617                         mtx_unlock(&hio_recv_list_lock[ncomp]);
1618                         goto done_queue;
1619                 }
1620                 if (hast_proto_recv_hdr(res->hr_remotein, &nv) < 0) {
1621                         pjdlog_errno(LOG_ERR,
1622                             "Unable to receive reply header");
1623                         rw_unlock(&hio_remote_lock[ncomp]);
1624                         remote_close(res, ncomp);
1625                         continue;
1626                 }
1627                 rw_unlock(&hio_remote_lock[ncomp]);
1628                 seq = nv_get_uint64(nv, "seq");
1629                 if (seq == 0) {
1630                         pjdlog_error("Header contains no 'seq' field.");
1631                         nv_free(nv);
1632                         continue;
1633                 }
1634                 mtx_lock(&hio_recv_list_lock[ncomp]);
1635                 TAILQ_FOREACH(hio, &hio_recv_list[ncomp], hio_next[ncomp]) {
1636                         if (hio->hio_ggio.gctl_seq == seq) {
1637                                 TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
1638                                     hio_next[ncomp]);
1639                                 break;
1640                         }
1641                 }
1642                 mtx_unlock(&hio_recv_list_lock[ncomp]);
1643                 if (hio == NULL) {
1644                         pjdlog_error("Found no request matching received 'seq' field (%ju).",
1645                             (uintmax_t)seq);
1646                         nv_free(nv);
1647                         continue;
1648                 }
1649                 ggio = &hio->hio_ggio;
1650                 error = nv_get_int16(nv, "error");
1651                 if (error != 0) {
1652                         /* Request failed on remote side. */
1653                         hio->hio_errors[ncomp] = error;
1654                         reqlog(LOG_WARNING, 0, ggio,
1655                             "Remote request failed (%s): ", strerror(error));
1656                         nv_free(nv);
1657                         goto done_queue;
1658                 }
1659                 switch (ggio->gctl_cmd) {
1660                 case BIO_READ:
1661                         rw_rlock(&hio_remote_lock[ncomp]);
1662                         if (!ISCONNECTED(res, ncomp)) {
1663                                 rw_unlock(&hio_remote_lock[ncomp]);
1664                                 nv_free(nv);
1665                                 goto done_queue;
1666                         }
1667                         if (hast_proto_recv_data(res, res->hr_remotein, nv,
1668                             ggio->gctl_data, ggio->gctl_length) < 0) {
1669                                 hio->hio_errors[ncomp] = errno;
1670                                 pjdlog_errno(LOG_ERR,
1671                                     "Unable to receive reply data");
1672                                 rw_unlock(&hio_remote_lock[ncomp]);
1673                                 nv_free(nv);
1674                                 remote_close(res, ncomp);
1675                                 goto done_queue;
1676                         }
1677                         rw_unlock(&hio_remote_lock[ncomp]);
1678                         break;
1679                 case BIO_WRITE:
1680                 case BIO_DELETE:
1681                 case BIO_FLUSH:
1682                         break;
1683                 default:
1684                         PJDLOG_ABORT("invalid condition");
1685                 }
1686                 hio->hio_errors[ncomp] = 0;
1687                 nv_free(nv);
1688 done_queue:
1689                 if (!refcount_release(&hio->hio_countdown))
1690                         continue;
1691                 if (ISSYNCREQ(hio)) {
1692                         mtx_lock(&sync_lock);
1693                         SYNCREQDONE(hio);
1694                         mtx_unlock(&sync_lock);
1695                         cv_signal(&sync_cond);
1696                 } else {
1697                         pjdlog_debug(2,
1698                             "remote_recv: (%p) Moving request to the done queue.",
1699                             hio);
1700                         QUEUE_INSERT2(hio, done);
1701                 }
1702         }
1703         /* NOTREACHED */
1704         return (NULL);
1705 }
1706
1707 /*
1708  * Thread sends answer to the kernel.
1709  */
1710 static void *
1711 ggate_send_thread(void *arg)
1712 {
1713         struct hast_resource *res = arg;
1714         struct g_gate_ctl_io *ggio;
1715         struct hio *hio;
1716         unsigned int ii, ncomps;
1717
1718         ncomps = HAST_NCOMPONENTS;
1719
1720         for (;;) {
1721                 pjdlog_debug(2, "ggate_send: Taking request.");
1722                 QUEUE_TAKE2(hio, done);
1723                 pjdlog_debug(2, "ggate_send: (%p) Got request.", hio);
1724                 ggio = &hio->hio_ggio;
1725                 for (ii = 0; ii < ncomps; ii++) {
1726                         if (hio->hio_errors[ii] == 0) {
1727                                 /*
1728                                  * One successful request is enough to declare
1729                                  * success.
1730                                  */
1731                                 ggio->gctl_error = 0;
1732                                 break;
1733                         }
1734                 }
1735                 if (ii == ncomps) {
1736                         /*
1737                          * None of the requests were successful.
1738                          * Use the error from local component except the
1739                          * case when we did only remote request.
1740                          */
1741                         if (ggio->gctl_cmd == BIO_READ &&
1742                             res->hr_syncsrc == HAST_SYNCSRC_SECONDARY)
1743                                 ggio->gctl_error = hio->hio_errors[1];
1744                         else
1745                                 ggio->gctl_error = hio->hio_errors[0];
1746                 }
1747                 if (ggio->gctl_error == 0 && ggio->gctl_cmd == BIO_WRITE) {
1748                         mtx_lock(&res->hr_amp_lock);
1749                         if (activemap_write_complete(res->hr_amp,
1750                             ggio->gctl_offset, ggio->gctl_length)) {
1751                                 res->hr_stat_activemap_update++;
1752                                 (void)hast_activemap_flush(res);
1753                         }
1754                         mtx_unlock(&res->hr_amp_lock);
1755                 }
1756                 if (ggio->gctl_cmd == BIO_WRITE) {
1757                         /*
1758                          * Unlock range we locked.
1759                          */
1760                         mtx_lock(&range_lock);
1761                         rangelock_del(range_regular, ggio->gctl_offset,
1762                             ggio->gctl_length);
1763                         if (range_sync_wait)
1764                                 cv_signal(&range_sync_cond);
1765                         mtx_unlock(&range_lock);
1766                         if (!hio->hio_done)
1767                                 write_complete(res, hio);
1768                 } else {
1769                         if (ioctl(res->hr_ggatefd, G_GATE_CMD_DONE, ggio) < 0) {
1770                                 primary_exit(EX_OSERR,
1771                                     "G_GATE_CMD_DONE failed");
1772                         }
1773                 }
1774                 pjdlog_debug(2,
1775                     "ggate_send: (%p) Moving request to the free queue.", hio);
1776                 QUEUE_INSERT2(hio, free);
1777         }
1778         /* NOTREACHED */
1779         return (NULL);
1780 }
1781
1782 /*
1783  * Thread synchronize local and remote components.
1784  */
1785 static void *
1786 sync_thread(void *arg __unused)
1787 {
1788         struct hast_resource *res = arg;
1789         struct hio *hio;
1790         struct g_gate_ctl_io *ggio;
1791         struct timeval tstart, tend, tdiff;
1792         unsigned int ii, ncomp, ncomps;
1793         off_t offset, length, synced;
1794         bool dorewind;
1795         int syncext;
1796
1797         ncomps = HAST_NCOMPONENTS;
1798         dorewind = true;
1799         synced = 0;
1800         offset = -1;
1801
1802         for (;;) {
1803                 mtx_lock(&sync_lock);
1804                 if (offset >= 0 && !sync_inprogress) {
1805                         gettimeofday(&tend, NULL);
1806                         timersub(&tend, &tstart, &tdiff);
1807                         pjdlog_info("Synchronization interrupted after %#.0T. "
1808                             "%NB synchronized so far.", &tdiff,
1809                             (intmax_t)synced);
1810                         event_send(res, EVENT_SYNCINTR);
1811                 }
1812                 while (!sync_inprogress) {
1813                         dorewind = true;
1814                         synced = 0;
1815                         cv_wait(&sync_cond, &sync_lock);
1816                 }
1817                 mtx_unlock(&sync_lock);
1818                 /*
1819                  * Obtain offset at which we should synchronize.
1820                  * Rewind synchronization if needed.
1821                  */
1822                 mtx_lock(&res->hr_amp_lock);
1823                 if (dorewind)
1824                         activemap_sync_rewind(res->hr_amp);
1825                 offset = activemap_sync_offset(res->hr_amp, &length, &syncext);
1826                 if (syncext != -1) {
1827                         /*
1828                          * We synchronized entire syncext extent, we can mark
1829                          * it as clean now.
1830                          */
1831                         if (activemap_extent_complete(res->hr_amp, syncext))
1832                                 (void)hast_activemap_flush(res);
1833                 }
1834                 mtx_unlock(&res->hr_amp_lock);
1835                 if (dorewind) {
1836                         dorewind = false;
1837                         if (offset < 0)
1838                                 pjdlog_info("Nodes are in sync.");
1839                         else {
1840                                 pjdlog_info("Synchronization started. %NB to go.",
1841                                     (intmax_t)(res->hr_extentsize *
1842                                     activemap_ndirty(res->hr_amp)));
1843                                 event_send(res, EVENT_SYNCSTART);
1844                                 gettimeofday(&tstart, NULL);
1845                         }
1846                 }
1847                 if (offset < 0) {
1848                         sync_stop();
1849                         pjdlog_debug(1, "Nothing to synchronize.");
1850                         /*
1851                          * Synchronization complete, make both localcnt and
1852                          * remotecnt equal.
1853                          */
1854                         ncomp = 1;
1855                         rw_rlock(&hio_remote_lock[ncomp]);
1856                         if (ISCONNECTED(res, ncomp)) {
1857                                 if (synced > 0) {
1858                                         int64_t bps;
1859
1860                                         gettimeofday(&tend, NULL);
1861                                         timersub(&tend, &tstart, &tdiff);
1862                                         bps = (int64_t)((double)synced /
1863                                             ((double)tdiff.tv_sec +
1864                                             (double)tdiff.tv_usec / 1000000));
1865                                         pjdlog_info("Synchronization complete. "
1866                                             "%NB synchronized in %#.0lT (%NB/sec).",
1867                                             (intmax_t)synced, &tdiff,
1868                                             (intmax_t)bps);
1869                                         event_send(res, EVENT_SYNCDONE);
1870                                 }
1871                                 mtx_lock(&metadata_lock);
1872                                 res->hr_syncsrc = HAST_SYNCSRC_UNDEF;
1873                                 res->hr_primary_localcnt =
1874                                     res->hr_secondary_remotecnt;
1875                                 res->hr_primary_remotecnt =
1876                                     res->hr_secondary_localcnt;
1877                                 pjdlog_debug(1,
1878                                     "Setting localcnt to %ju and remotecnt to %ju.",
1879                                     (uintmax_t)res->hr_primary_localcnt,
1880                                     (uintmax_t)res->hr_primary_remotecnt);
1881                                 (void)metadata_write(res);
1882                                 mtx_unlock(&metadata_lock);
1883                         }
1884                         rw_unlock(&hio_remote_lock[ncomp]);
1885                         continue;
1886                 }
1887                 pjdlog_debug(2, "sync: Taking free request.");
1888                 QUEUE_TAKE2(hio, free);
1889                 pjdlog_debug(2, "sync: (%p) Got free request.", hio);
1890                 /*
1891                  * Lock the range we are going to synchronize. We don't want
1892                  * race where someone writes between our read and write.
1893                  */
1894                 for (;;) {
1895                         mtx_lock(&range_lock);
1896                         if (rangelock_islocked(range_regular, offset, length)) {
1897                                 pjdlog_debug(2,
1898                                     "sync: Range offset=%jd length=%jd locked.",
1899                                     (intmax_t)offset, (intmax_t)length);
1900                                 range_sync_wait = true;
1901                                 cv_wait(&range_sync_cond, &range_lock);
1902                                 range_sync_wait = false;
1903                                 mtx_unlock(&range_lock);
1904                                 continue;
1905                         }
1906                         if (rangelock_add(range_sync, offset, length) < 0) {
1907                                 mtx_unlock(&range_lock);
1908                                 pjdlog_debug(2,
1909                                     "sync: Range offset=%jd length=%jd is already locked, waiting.",
1910                                     (intmax_t)offset, (intmax_t)length);
1911                                 sleep(1);
1912                                 continue;
1913                         }
1914                         mtx_unlock(&range_lock);
1915                         break;
1916                 }
1917                 /*
1918                  * First read the data from synchronization source.
1919                  */
1920                 SYNCREQ(hio);
1921                 ggio = &hio->hio_ggio;
1922                 ggio->gctl_cmd = BIO_READ;
1923                 ggio->gctl_offset = offset;
1924                 ggio->gctl_length = length;
1925                 ggio->gctl_error = 0;
1926                 hio->hio_done = false;
1927                 hio->hio_replication = res->hr_replication;
1928                 for (ii = 0; ii < ncomps; ii++)
1929                         hio->hio_errors[ii] = EINVAL;
1930                 reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
1931                     hio);
1932                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
1933                     hio);
1934                 mtx_lock(&metadata_lock);
1935                 if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1936                         /*
1937                          * This range is up-to-date on local component,
1938                          * so handle request locally.
1939                          */
1940                          /* Local component is 0 for now. */
1941                         ncomp = 0;
1942                 } else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
1943                         PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
1944                         /*
1945                          * This range is out-of-date on local component,
1946                          * so send request to the remote node.
1947                          */
1948                          /* Remote component is 1 for now. */
1949                         ncomp = 1;
1950                 }
1951                 mtx_unlock(&metadata_lock);
1952                 refcount_init(&hio->hio_countdown, 1);
1953                 QUEUE_INSERT1(hio, send, ncomp);
1954
1955                 /*
1956                  * Let's wait for READ to finish.
1957                  */
1958                 mtx_lock(&sync_lock);
1959                 while (!ISSYNCREQDONE(hio))
1960                         cv_wait(&sync_cond, &sync_lock);
1961                 mtx_unlock(&sync_lock);
1962
1963                 if (hio->hio_errors[ncomp] != 0) {
1964                         pjdlog_error("Unable to read synchronization data: %s.",
1965                             strerror(hio->hio_errors[ncomp]));
1966                         goto free_queue;
1967                 }
1968
1969                 /*
1970                  * We read the data from synchronization source, now write it
1971                  * to synchronization target.
1972                  */
1973                 SYNCREQ(hio);
1974                 ggio->gctl_cmd = BIO_WRITE;
1975                 for (ii = 0; ii < ncomps; ii++)
1976                         hio->hio_errors[ii] = EINVAL;
1977                 reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
1978                     hio);
1979                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
1980                     hio);
1981                 mtx_lock(&metadata_lock);
1982                 if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
1983                         /*
1984                          * This range is up-to-date on local component,
1985                          * so we update remote component.
1986                          */
1987                          /* Remote component is 1 for now. */
1988                         ncomp = 1;
1989                 } else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
1990                         PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
1991                         /*
1992                          * This range is out-of-date on local component,
1993                          * so we update it.
1994                          */
1995                          /* Local component is 0 for now. */
1996                         ncomp = 0;
1997                 }
1998                 mtx_unlock(&metadata_lock);
1999
2000                 pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
2001                     hio);
2002                 refcount_init(&hio->hio_countdown, 1);
2003                 QUEUE_INSERT1(hio, send, ncomp);
2004
2005                 /*
2006                  * Let's wait for WRITE to finish.
2007                  */
2008                 mtx_lock(&sync_lock);
2009                 while (!ISSYNCREQDONE(hio))
2010                         cv_wait(&sync_cond, &sync_lock);
2011                 mtx_unlock(&sync_lock);
2012
2013                 if (hio->hio_errors[ncomp] != 0) {
2014                         pjdlog_error("Unable to write synchronization data: %s.",
2015                             strerror(hio->hio_errors[ncomp]));
2016                         goto free_queue;
2017                 }
2018
2019                 synced += length;
2020 free_queue:
2021                 mtx_lock(&range_lock);
2022                 rangelock_del(range_sync, offset, length);
2023                 if (range_regular_wait)
2024                         cv_signal(&range_regular_cond);
2025                 mtx_unlock(&range_lock);
2026                 pjdlog_debug(2, "sync: (%p) Moving request to the free queue.",
2027                     hio);
2028                 QUEUE_INSERT2(hio, free);
2029         }
2030         /* NOTREACHED */
2031         return (NULL);
2032 }
2033
2034 void
2035 primary_config_reload(struct hast_resource *res, struct nv *nv)
2036 {
2037         unsigned int ii, ncomps;
2038         int modified, vint;
2039         const char *vstr;
2040
2041         pjdlog_info("Reloading configuration...");
2042
2043         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
2044         PJDLOG_ASSERT(gres == res);
2045         nv_assert(nv, "remoteaddr");
2046         nv_assert(nv, "sourceaddr");
2047         nv_assert(nv, "replication");
2048         nv_assert(nv, "checksum");
2049         nv_assert(nv, "compression");
2050         nv_assert(nv, "timeout");
2051         nv_assert(nv, "exec");
2052         nv_assert(nv, "metaflush");
2053
2054         ncomps = HAST_NCOMPONENTS;
2055
2056 #define MODIFIED_REMOTEADDR     0x01
2057 #define MODIFIED_SOURCEADDR     0x02
2058 #define MODIFIED_REPLICATION    0x04
2059 #define MODIFIED_CHECKSUM       0x08
2060 #define MODIFIED_COMPRESSION    0x10
2061 #define MODIFIED_TIMEOUT        0x20
2062 #define MODIFIED_EXEC           0x40
2063 #define MODIFIED_METAFLUSH      0x80
2064         modified = 0;
2065
2066         vstr = nv_get_string(nv, "remoteaddr");
2067         if (strcmp(gres->hr_remoteaddr, vstr) != 0) {
2068                 /*
2069                  * Don't copy res->hr_remoteaddr to gres just yet.
2070                  * We want remote_close() to log disconnect from the old
2071                  * addresses, not from the new ones.
2072                  */
2073                 modified |= MODIFIED_REMOTEADDR;
2074         }
2075         vstr = nv_get_string(nv, "sourceaddr");
2076         if (strcmp(gres->hr_sourceaddr, vstr) != 0) {
2077                 strlcpy(gres->hr_sourceaddr, vstr, sizeof(gres->hr_sourceaddr));
2078                 modified |= MODIFIED_SOURCEADDR;
2079         }
2080         vint = nv_get_int32(nv, "replication");
2081         if (gres->hr_replication != vint) {
2082                 gres->hr_replication = vint;
2083                 modified |= MODIFIED_REPLICATION;
2084         }
2085         vint = nv_get_int32(nv, "checksum");
2086         if (gres->hr_checksum != vint) {
2087                 gres->hr_checksum = vint;
2088                 modified |= MODIFIED_CHECKSUM;
2089         }
2090         vint = nv_get_int32(nv, "compression");
2091         if (gres->hr_compression != vint) {
2092                 gres->hr_compression = vint;
2093                 modified |= MODIFIED_COMPRESSION;
2094         }
2095         vint = nv_get_int32(nv, "timeout");
2096         if (gres->hr_timeout != vint) {
2097                 gres->hr_timeout = vint;
2098                 modified |= MODIFIED_TIMEOUT;
2099         }
2100         vstr = nv_get_string(nv, "exec");
2101         if (strcmp(gres->hr_exec, vstr) != 0) {
2102                 strlcpy(gres->hr_exec, vstr, sizeof(gres->hr_exec));
2103                 modified |= MODIFIED_EXEC;
2104         }
2105         vint = nv_get_int32(nv, "metaflush");
2106         if (gres->hr_metaflush != vint) {
2107                 gres->hr_metaflush = vint;
2108                 modified |= MODIFIED_METAFLUSH;
2109         }
2110
2111         /*
2112          * Change timeout for connected sockets.
2113          * Don't bother if we need to reconnect.
2114          */
2115         if ((modified & MODIFIED_TIMEOUT) != 0 &&
2116             (modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR)) == 0) {
2117                 for (ii = 0; ii < ncomps; ii++) {
2118                         if (!ISREMOTE(ii))
2119                                 continue;
2120                         rw_rlock(&hio_remote_lock[ii]);
2121                         if (!ISCONNECTED(gres, ii)) {
2122                                 rw_unlock(&hio_remote_lock[ii]);
2123                                 continue;
2124                         }
2125                         rw_unlock(&hio_remote_lock[ii]);
2126                         if (proto_timeout(gres->hr_remotein,
2127                             gres->hr_timeout) < 0) {
2128                                 pjdlog_errno(LOG_WARNING,
2129                                     "Unable to set connection timeout");
2130                         }
2131                         if (proto_timeout(gres->hr_remoteout,
2132                             gres->hr_timeout) < 0) {
2133                                 pjdlog_errno(LOG_WARNING,
2134                                     "Unable to set connection timeout");
2135                         }
2136                 }
2137         }
2138         if ((modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR)) != 0) {
2139                 for (ii = 0; ii < ncomps; ii++) {
2140                         if (!ISREMOTE(ii))
2141                                 continue;
2142                         remote_close(gres, ii);
2143                 }
2144                 if (modified & MODIFIED_REMOTEADDR) {
2145                         vstr = nv_get_string(nv, "remoteaddr");
2146                         strlcpy(gres->hr_remoteaddr, vstr,
2147                             sizeof(gres->hr_remoteaddr));
2148                 }
2149         }
2150 #undef  MODIFIED_REMOTEADDR
2151 #undef  MODIFIED_SOURCEADDR
2152 #undef  MODIFIED_REPLICATION
2153 #undef  MODIFIED_CHECKSUM
2154 #undef  MODIFIED_COMPRESSION
2155 #undef  MODIFIED_TIMEOUT
2156 #undef  MODIFIED_EXEC
2157 #undef  MODIFIED_METAFLUSH
2158
2159         pjdlog_info("Configuration reloaded successfully.");
2160 }
2161
2162 static void
2163 guard_one(struct hast_resource *res, unsigned int ncomp)
2164 {
2165         struct proto_conn *in, *out;
2166
2167         if (!ISREMOTE(ncomp))
2168                 return;
2169
2170         rw_rlock(&hio_remote_lock[ncomp]);
2171
2172         if (!real_remote(res)) {
2173                 rw_unlock(&hio_remote_lock[ncomp]);
2174                 return;
2175         }
2176
2177         if (ISCONNECTED(res, ncomp)) {
2178                 PJDLOG_ASSERT(res->hr_remotein != NULL);
2179                 PJDLOG_ASSERT(res->hr_remoteout != NULL);
2180                 rw_unlock(&hio_remote_lock[ncomp]);
2181                 pjdlog_debug(2, "remote_guard: Connection to %s is ok.",
2182                     res->hr_remoteaddr);
2183                 return;
2184         }
2185
2186         PJDLOG_ASSERT(res->hr_remotein == NULL);
2187         PJDLOG_ASSERT(res->hr_remoteout == NULL);
2188         /*
2189          * Upgrade the lock. It doesn't have to be atomic as no other thread
2190          * can change connection status from disconnected to connected.
2191          */
2192         rw_unlock(&hio_remote_lock[ncomp]);
2193         pjdlog_debug(2, "remote_guard: Reconnecting to %s.",
2194             res->hr_remoteaddr);
2195         in = out = NULL;
2196         if (init_remote(res, &in, &out) == 0) {
2197                 rw_wlock(&hio_remote_lock[ncomp]);
2198                 PJDLOG_ASSERT(res->hr_remotein == NULL);
2199                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
2200                 PJDLOG_ASSERT(in != NULL && out != NULL);
2201                 res->hr_remotein = in;
2202                 res->hr_remoteout = out;
2203                 rw_unlock(&hio_remote_lock[ncomp]);
2204                 pjdlog_info("Successfully reconnected to %s.",
2205                     res->hr_remoteaddr);
2206                 sync_start();
2207         } else {
2208                 /* Both connections should be NULL. */
2209                 PJDLOG_ASSERT(res->hr_remotein == NULL);
2210                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
2211                 PJDLOG_ASSERT(in == NULL && out == NULL);
2212                 pjdlog_debug(2, "remote_guard: Reconnect to %s failed.",
2213                     res->hr_remoteaddr);
2214         }
2215 }
2216
2217 /*
2218  * Thread guards remote connections and reconnects when needed, handles
2219  * signals, etc.
2220  */
2221 static void *
2222 guard_thread(void *arg)
2223 {
2224         struct hast_resource *res = arg;
2225         unsigned int ii, ncomps;
2226         struct timespec timeout;
2227         time_t lastcheck, now;
2228         sigset_t mask;
2229         int signo;
2230
2231         ncomps = HAST_NCOMPONENTS;
2232         lastcheck = time(NULL);
2233
2234         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
2235         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
2236         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
2237
2238         timeout.tv_sec = HAST_KEEPALIVE;
2239         timeout.tv_nsec = 0;
2240         signo = -1;
2241
2242         for (;;) {
2243                 switch (signo) {
2244                 case SIGINT:
2245                 case SIGTERM:
2246                         sigexit_received = true;
2247                         primary_exitx(EX_OK,
2248                             "Termination signal received, exiting.");
2249                         break;
2250                 default:
2251                         break;
2252                 }
2253
2254                 /*
2255                  * Don't check connections until we fully started,
2256                  * as we may still be looping, waiting for remote node
2257                  * to switch from primary to secondary.
2258                  */
2259                 if (fullystarted) {
2260                         pjdlog_debug(2, "remote_guard: Checking connections.");
2261                         now = time(NULL);
2262                         if (lastcheck + HAST_KEEPALIVE <= now) {
2263                                 for (ii = 0; ii < ncomps; ii++)
2264                                         guard_one(res, ii);
2265                                 lastcheck = now;
2266                         }
2267                 }
2268                 signo = sigtimedwait(&mask, NULL, &timeout);
2269         }
2270         /* NOTREACHED */
2271         return (NULL);
2272 }