sbin/hastd/secondary.c

   1 /*-
   2  * Copyright (c) 2009-2010 The FreeBSD Foundation
   3  * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
   4  * All rights reserved.
   5  *
   6  * This software was developed by Pawel Jakub Dawidek under sponsorship from
   7  * the FreeBSD Foundation.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 #include <sys/param.h>
  35 #include <sys/time.h>
  36 #include <sys/bio.h>
  37 #include <sys/disk.h>
  38 #include <sys/stat.h>
  39
  40 #include <err.h>
  41 #include <errno.h>
  42 #include <fcntl.h>
  43 #include <libgeom.h>
  44 #include <pthread.h>
  45 #include <signal.h>
  46 #include <stdint.h>
  47 #include <stdio.h>
  48 #include <string.h>
  49 #include <sysexits.h>
  50 #include <unistd.h>
  51
  52 #include <activemap.h>
  53 #include <nv.h>
  54 #include <pjdlog.h>
  55
  56 #include "control.h"
  57 #include "event.h"
  58 #include "hast.h"
  59 #include "hast_proto.h"
  60 #include "hastd.h"
  61 #include "hooks.h"
  62 #include "metadata.h"
  63 #include "proto.h"
  64 #include "subr.h"
  65 #include "synch.h"
  66
  67 struct hio {
  68         uint64_t         hio_seq;
  69         int              hio_error;
  70         void            *hio_data;
  71         uint8_t          hio_cmd;
  72         uint64_t         hio_offset;
  73         uint64_t         hio_length;
  74         bool             hio_memsync;
  75         TAILQ_ENTRY(hio) hio_next;
  76 };
  77
  78 static struct hast_resource *gres;
  79
  80 /*
  81  * Free list holds unused structures. When free list is empty, we have to wait
  82  * until some in-progress requests are freed.
  83  */
  84 static TAILQ_HEAD(, hio) hio_free_list;
  85 static size_t hio_free_list_size;
  86 static pthread_mutex_t hio_free_list_lock;
  87 static pthread_cond_t hio_free_list_cond;
  88 /*
  89  * Disk thread (the one that does I/O requests) takes requests from this list.
  90  */
  91 static TAILQ_HEAD(, hio) hio_disk_list;
  92 static size_t hio_disk_list_size;
  93 static pthread_mutex_t hio_disk_list_lock;
  94 static pthread_cond_t hio_disk_list_cond;
  95 /*
  96  * Thread that sends requests back to primary takes requests from this list.
  97  */
  98 static TAILQ_HEAD(, hio) hio_send_list;
  99 static size_t hio_send_list_size;
 100 static pthread_mutex_t hio_send_list_lock;
 101 static pthread_cond_t hio_send_list_cond;
 102
 103 /*
 104  * Maximum number of outstanding I/O requests.
 105  */
 106 #define HAST_HIO_MAX    256
 107
 108 static void *recv_thread(void *arg);
 109 static void *disk_thread(void *arg);
 110 static void *send_thread(void *arg);
 111
 112 #define QUEUE_INSERT(name, hio) do {                                    \
 113         bool _wakeup;                                                   \
 114                                                                         \
 115         mtx_lock(&hio_##name##_list_lock);                              \
 116         _wakeup = TAILQ_EMPTY(&hio_##name##_list);                      \
 117         TAILQ_INSERT_TAIL(&hio_##name##_list, (hio), hio_next);         \
 118         hio_##name##_list_size++;                                       \
 119         mtx_unlock(&hio_##name##_list_lock);                            \
 120         if (_wakeup)                                                    \
 121                 cv_broadcast(&hio_##name##_list_cond);                  \
 122 } while (0)
 123 #define QUEUE_TAKE(name, hio)   do {                                    \
 124         mtx_lock(&hio_##name##_list_lock);                              \
 125         while (((hio) = TAILQ_FIRST(&hio_##name##_list)) == NULL) {     \
 126                 cv_wait(&hio_##name##_list_cond,                        \
 127                     &hio_##name##_list_lock);                           \
 128         }                                                               \
 129         PJDLOG_ASSERT(hio_##name##_list_size != 0);                     \
 130         hio_##name##_list_size--;                                       \
 131         TAILQ_REMOVE(&hio_##name##_list, (hio), hio_next);              \
 132         mtx_unlock(&hio_##name##_list_lock);                            \
 133 } while (0)
 134
 135 static void
 136 output_status_aux(struct nv *nvout)
 137 {
 138
 139         nv_add_uint64(nvout, (uint64_t)hio_free_list_size, "idle_queue_size");
 140         nv_add_uint64(nvout, (uint64_t)hio_disk_list_size, "local_queue_size");
 141         nv_add_uint64(nvout, (uint64_t)hio_send_list_size, "send_queue_size");
 142 }
 143
 144 static void
 145 hio_clear(struct hio *hio)
 146 {
 147
 148         hio->hio_seq = 0;
 149         hio->hio_error = 0;
 150         hio->hio_cmd = HIO_UNDEF;
 151         hio->hio_offset = 0;
 152         hio->hio_length = 0;
 153         hio->hio_memsync = false;
 154 }
 155
 156 static void
 157 hio_copy(const struct hio *srchio, struct hio *dsthio)
 158 {
 159
 160         /*
 161          * We don't copy hio_error, hio_data and hio_next fields.
 162          */
 163
 164         dsthio->hio_seq = srchio->hio_seq;
 165         dsthio->hio_cmd = srchio->hio_cmd;
 166         dsthio->hio_offset = srchio->hio_offset;
 167         dsthio->hio_length = srchio->hio_length;
 168         dsthio->hio_memsync = srchio->hio_memsync;
 169 }
 170
 171 static void
 172 init_environment(void)
 173 {
 174         struct hio *hio;
 175         unsigned int ii;
 176
 177         /*
 178          * Initialize lists, their locks and theirs condition variables.
 179          */
 180         TAILQ_INIT(&hio_free_list);
 181         mtx_init(&hio_free_list_lock);
 182         cv_init(&hio_free_list_cond);
 183         TAILQ_INIT(&hio_disk_list);
 184         mtx_init(&hio_disk_list_lock);
 185         cv_init(&hio_disk_list_cond);
 186         TAILQ_INIT(&hio_send_list);
 187         mtx_init(&hio_send_list_lock);
 188         cv_init(&hio_send_list_cond);
 189
 190         /*
 191          * Allocate requests pool and initialize requests.
 192          */
 193         for (ii = 0; ii < HAST_HIO_MAX; ii++) {
 194                 hio = malloc(sizeof(*hio));
 195                 if (hio == NULL) {
 196                         pjdlog_exitx(EX_TEMPFAIL,
 197                             "Unable to allocate memory (%zu bytes) for hio request.",
 198                             sizeof(*hio));
 199                 }
 200                 hio->hio_data = malloc(MAXPHYS);
 201                 if (hio->hio_data == NULL) {
 202                         pjdlog_exitx(EX_TEMPFAIL,
 203                             "Unable to allocate memory (%zu bytes) for gctl_data.",
 204                             (size_t)MAXPHYS);
 205                 }
 206                 hio_clear(hio);
 207                 TAILQ_INSERT_HEAD(&hio_free_list, hio, hio_next);
 208                 hio_free_list_size++;
 209         }
 210 }
 211
 212 static void
 213 init_local(struct hast_resource *res)
 214 {
 215
 216         if (metadata_read(res, true) == -1)
 217                 exit(EX_NOINPUT);
 218 }
 219
 220 static void
 221 init_remote(struct hast_resource *res, struct nv *nvin)
 222 {
 223         uint64_t resuid;
 224         struct nv *nvout;
 225         unsigned char *map;
 226         size_t mapsize;
 227
 228 #ifdef notyet
 229         /* Setup direction. */
 230         if (proto_send(res->hr_remoteout, NULL, 0) == -1)
 231                 pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
 232 #endif
 233
 234         nvout = nv_alloc();
 235         nv_add_int64(nvout, (int64_t)res->hr_datasize, "datasize");
 236         nv_add_int32(nvout, (int32_t)res->hr_extentsize, "extentsize");
 237         resuid = nv_get_uint64(nvin, "resuid");
 238         res->hr_primary_localcnt = nv_get_uint64(nvin, "localcnt");
 239         res->hr_primary_remotecnt = nv_get_uint64(nvin, "remotecnt");
 240         nv_add_uint64(nvout, res->hr_secondary_localcnt, "localcnt");
 241         nv_add_uint64(nvout, res->hr_secondary_remotecnt, "remotecnt");
 242         mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize -
 243             METADATA_SIZE, res->hr_extentsize, res->hr_local_sectorsize);
 244         map = malloc(mapsize);
 245         if (map == NULL) {
 246                 pjdlog_exitx(EX_TEMPFAIL,
 247                     "Unable to allocate memory (%zu bytes) for activemap.",
 248                     mapsize);
 249         }
 250         /*
 251          * When we work as primary and secondary is missing we will increase
 252          * localcnt in our metadata. When secondary is connected and synced
 253          * we make localcnt be equal to remotecnt, which means nodes are more
 254          * or less in sync.
 255          * Split-brain condition is when both nodes are not able to communicate
 256          * and are both configured as primary nodes. In turn, they can both
 257          * make incompatible changes to the data and we have to detect that.
 258          * Under split-brain condition we will increase our localcnt on first
 259          * write and remote node will increase its localcnt on first write.
 260          * When we connect we can see that primary's localcnt is greater than
 261          * our remotecnt (primary was modified while we weren't watching) and
 262          * our localcnt is greater than primary's remotecnt (we were modified
 263          * while primary wasn't watching).
 264          * There are many possible combinations which are all gathered below.
 265          * Don't pay too much attention to exact numbers, the more important
 266          * is to compare them. We compare secondary's local with primary's
 267          * remote and secondary's remote with primary's local.
 268          * Note that every case where primary's localcnt is smaller than
 269          * secondary's remotecnt and where secondary's localcnt is smaller than
 270          * primary's remotecnt should be impossible in practise. We will perform
 271          * full synchronization then. Those cases are marked with an asterisk.
 272          * Regular synchronization means that only extents marked as dirty are
 273          * synchronized (regular synchronization).
 274          *
 275          * SECONDARY METADATA PRIMARY METADATA
 276          * local=3 remote=3   local=2 remote=2*  ?! Full sync from secondary.
 277          * local=3 remote=3   local=2 remote=3*  ?! Full sync from primary.
 278          * local=3 remote=3   local=2 remote=4*  ?! Full sync from primary.
 279          * local=3 remote=3   local=3 remote=2   Primary is out-of-date,
 280          *                                       regular sync from secondary.
 281          * local=3 remote=3   local=3 remote=3   Regular sync just in case.
 282          * local=3 remote=3   local=3 remote=4*  ?! Full sync from primary.
 283          * local=3 remote=3   local=4 remote=2   Split-brain condition.
 284          * local=3 remote=3   local=4 remote=3   Secondary out-of-date,
 285          *                                       regular sync from primary.
 286          * local=3 remote=3   local=4 remote=4*  ?! Full sync from primary.
 287          */
 288         if (res->hr_resuid == 0) {
 289                 /*
 290                  * Provider is used for the first time. If primary node done no
 291                  * writes yet as well (we will find "virgin" argument) then
 292                  * there is no need to synchronize anything. If primary node
 293                  * done any writes already we have to synchronize everything.
 294                  */
 295                 PJDLOG_ASSERT(res->hr_secondary_localcnt == 0);
 296                 res->hr_resuid = resuid;
 297                 if (metadata_write(res) == -1)
 298                         exit(EX_NOINPUT);
 299                 if (nv_exists(nvin, "virgin")) {
 300                         free(map);
 301                         map = NULL;
 302                         mapsize = 0;
 303                 } else {
 304                         memset(map, 0xff, mapsize);
 305                 }
 306                 nv_add_int8(nvout, 1, "virgin");
 307                 nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
 308         } else if (res->hr_resuid != resuid) {
 309                 char errmsg[256];
 310
 311                 free(map);
 312                 (void)snprintf(errmsg, sizeof(errmsg),
 313                     "Resource unique ID mismatch (primary=%ju, secondary=%ju).",
 314                     (uintmax_t)resuid, (uintmax_t)res->hr_resuid);
 315                 pjdlog_error("%s", errmsg);
 316                 nv_add_string(nvout, errmsg, "errmsg");
 317                 if (hast_proto_send(res, res->hr_remotein, nvout,
 318                     NULL, 0) == -1) {
 319                         pjdlog_exit(EX_TEMPFAIL,
 320                             "Unable to send response to %s",
 321                             res->hr_remoteaddr);
 322                 }
 323                 nv_free(nvout);
 324                 exit(EX_CONFIG);
 325         } else if (
 326             /* Is primary out-of-date? */
 327             (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
 328              res->hr_secondary_remotecnt == res->hr_primary_localcnt) ||
 329             /* Are the nodes more or less in sync? */
 330             (res->hr_secondary_localcnt == res->hr_primary_remotecnt &&
 331              res->hr_secondary_remotecnt == res->hr_primary_localcnt) ||
 332             /* Is secondary out-of-date? */
 333             (res->hr_secondary_localcnt == res->hr_primary_remotecnt &&
 334              res->hr_secondary_remotecnt < res->hr_primary_localcnt)) {
 335                 /*
 336                  * Nodes are more or less in sync or one of the nodes is
 337                  * out-of-date.
 338                  * It doesn't matter at this point which one, we just have to
 339                  * send out local bitmap to the remote node.
 340                  */
 341                 if (pread(res->hr_localfd, map, mapsize, METADATA_SIZE) !=
 342                     (ssize_t)mapsize) {
 343                         pjdlog_exit(LOG_ERR, "Unable to read activemap");
 344                 }
 345                 if (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
 346                      res->hr_secondary_remotecnt == res->hr_primary_localcnt) {
 347                         /* Primary is out-of-date, sync from secondary. */
 348                         nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc");
 349                 } else {
 350                         /*
 351                          * Secondary is out-of-date or counts match.
 352                          * Sync from primary.
 353                          */
 354                         nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
 355                 }
 356         } else if (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
 357              res->hr_primary_localcnt > res->hr_secondary_remotecnt) {
 358                 /*
 359                  * Not good, we have split-brain condition.
 360                  */
 361                 free(map);
 362                 pjdlog_error("Split-brain detected, exiting.");
 363                 nv_add_string(nvout, "Split-brain condition!", "errmsg");
 364                 if (hast_proto_send(res, res->hr_remotein, nvout,
 365                     NULL, 0) == -1) {
 366                         pjdlog_exit(EX_TEMPFAIL,
 367                             "Unable to send response to %s",
 368                             res->hr_remoteaddr);
 369                 }
 370                 nv_free(nvout);
 371                 /* Exit on split-brain. */
 372                 event_send(res, EVENT_SPLITBRAIN);
 373                 exit(EX_CONFIG);
 374         } else /* if (res->hr_secondary_localcnt < res->hr_primary_remotecnt ||
 375             res->hr_primary_localcnt < res->hr_secondary_remotecnt) */ {
 376                 /*
 377                  * This should never happen in practise, but we will perform
 378                  * full synchronization.
 379                  */
 380                 PJDLOG_ASSERT(res->hr_secondary_localcnt < res->hr_primary_remotecnt ||
 381                     res->hr_primary_localcnt < res->hr_secondary_remotecnt);
 382                 mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize -
 383                     METADATA_SIZE, res->hr_extentsize,
 384                     res->hr_local_sectorsize);
 385                 memset(map, 0xff, mapsize);
 386                 if (res->hr_secondary_localcnt > res->hr_primary_remotecnt) {
 387                         /* In this one of five cases sync from secondary. */
 388                         nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc");
 389                 } else {
 390                         /* For the rest four cases sync from primary. */
 391                         nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
 392                 }
 393                 pjdlog_warning("This should never happen, asking for full synchronization (primary(local=%ju, remote=%ju), secondary(local=%ju, remote=%ju)).",
 394                     (uintmax_t)res->hr_primary_localcnt,
 395                     (uintmax_t)res->hr_primary_remotecnt,
 396                     (uintmax_t)res->hr_secondary_localcnt,
 397                     (uintmax_t)res->hr_secondary_remotecnt);
 398         }
 399         nv_add_uint32(nvout, (uint32_t)mapsize, "mapsize");
 400         if (hast_proto_send(res, res->hr_remotein, nvout, map, mapsize) == -1) {
 401                 pjdlog_exit(EX_TEMPFAIL, "Unable to send activemap to %s",
 402                     res->hr_remoteaddr);
 403         }
 404         if (map != NULL)
 405                 free(map);
 406         nv_free(nvout);
 407 #ifdef notyet
 408         /* Setup direction. */
 409         if (proto_recv(res->hr_remotein, NULL, 0) == -1)
 410                 pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
 411 #endif
 412 }
 413
 414 void
 415 hastd_secondary(struct hast_resource *res, struct nv *nvin)
 416 {
 417         sigset_t mask;
 418         pthread_t td;
 419         pid_t pid;
 420         int error, mode, debuglevel;
 421
 422         /*
 423          * Create communication channel between parent and child.
 424          */
 425         if (proto_client(NULL, "socketpair://", &res->hr_ctrl) == -1) {
 426                 KEEP_ERRNO((void)pidfile_remove(pfh));
 427                 pjdlog_exit(EX_OSERR,
 428                     "Unable to create control sockets between parent and child");
 429         }
 430         /*
 431          * Create communication channel between child and parent.
 432          */
 433         if (proto_client(NULL, "socketpair://", &res->hr_event) == -1) {
 434                 KEEP_ERRNO((void)pidfile_remove(pfh));
 435                 pjdlog_exit(EX_OSERR,
 436                     "Unable to create event sockets between child and parent");
 437         }
 438
 439         pid = fork();
 440         if (pid == -1) {
 441                 KEEP_ERRNO((void)pidfile_remove(pfh));
 442                 pjdlog_exit(EX_OSERR, "Unable to fork");
 443         }
 444
 445         if (pid > 0) {
 446                 /* This is parent. */
 447                 proto_close(res->hr_remotein);
 448                 res->hr_remotein = NULL;
 449                 proto_close(res->hr_remoteout);
 450                 res->hr_remoteout = NULL;
 451                 /* Declare that we are receiver. */
 452                 proto_recv(res->hr_event, NULL, 0);
 453                 /* Declare that we are sender. */
 454                 proto_send(res->hr_ctrl, NULL, 0);
 455                 res->hr_workerpid = pid;
 456                 return;
 457         }
 458
 459         gres = res;
 460         res->output_status_aux = output_status_aux;
 461         mode = pjdlog_mode_get();
 462         debuglevel = pjdlog_debug_get();
 463
 464         /* Declare that we are sender. */
 465         proto_send(res->hr_event, NULL, 0);
 466         /* Declare that we are receiver. */
 467         proto_recv(res->hr_ctrl, NULL, 0);
 468         descriptors_cleanup(res);
 469
 470         descriptors_assert(res, mode);
 471
 472         pjdlog_init(mode);
 473         pjdlog_debug_set(debuglevel);
 474         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 475         setproctitle("%s (%s)", res->hr_name, role2str(res->hr_role));
 476
 477         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
 478         PJDLOG_VERIFY(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 479
 480         /* Error in setting timeout is not critical, but why should it fail? */
 481         if (proto_timeout(res->hr_remotein, 2 * HAST_KEEPALIVE) == -1)
 482                 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
 483         if (proto_timeout(res->hr_remoteout, res->hr_timeout) == -1)
 484                 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
 485
 486         init_local(res);
 487         init_environment();
 488
 489         if (drop_privs(res) != 0)
 490                 exit(EX_CONFIG);
 491         pjdlog_info("Privileges successfully dropped.");
 492
 493         /*
 494          * Create the control thread before sending any event to the parent,
 495          * as we can deadlock when parent sends control request to worker,
 496          * but worker has no control thread started yet, so parent waits.
 497          * In the meantime worker sends an event to the parent, but parent
 498          * is unable to handle the event, because it waits for control
 499          * request response.
 500          */
 501         error = pthread_create(&td, NULL, ctrl_thread, res);
 502         PJDLOG_ASSERT(error == 0);
 503
 504         init_remote(res, nvin);
 505         event_send(res, EVENT_CONNECT);
 506
 507         error = pthread_create(&td, NULL, recv_thread, res);
 508         PJDLOG_ASSERT(error == 0);
 509         error = pthread_create(&td, NULL, disk_thread, res);
 510         PJDLOG_ASSERT(error == 0);
 511         (void)send_thread(res);
 512 }
 513
 514 static void
 515 reqlog(int loglevel, int debuglevel, int error, struct hio *hio,
 516     const char *fmt, ...)
 517 {
 518         char msg[1024];
 519         va_list ap;
 520         int len;
 521
 522         va_start(ap, fmt);
 523         len = vsnprintf(msg, sizeof(msg), fmt, ap);
 524         va_end(ap);
 525         if ((size_t)len < sizeof(msg)) {
 526                 switch (hio->hio_cmd) {
 527                 case HIO_READ:
 528                         (void)snprintf(msg + len, sizeof(msg) - len,
 529                             "READ(%ju, %ju).", (uintmax_t)hio->hio_offset,
 530                             (uintmax_t)hio->hio_length);
 531                         break;
 532                 case HIO_DELETE:
 533                         (void)snprintf(msg + len, sizeof(msg) - len,
 534                             "DELETE(%ju, %ju).", (uintmax_t)hio->hio_offset,
 535                             (uintmax_t)hio->hio_length);
 536                         break;
 537                 case HIO_FLUSH:
 538                         (void)snprintf(msg + len, sizeof(msg) - len, "FLUSH.");
 539                         break;
 540                 case HIO_WRITE:
 541                         (void)snprintf(msg + len, sizeof(msg) - len,
 542                             "WRITE(%ju, %ju).", (uintmax_t)hio->hio_offset,
 543                             (uintmax_t)hio->hio_length);
 544                         break;
 545                 case HIO_KEEPALIVE:
 546                         (void)snprintf(msg + len, sizeof(msg) - len, "KEEPALIVE.");
 547                         break;
 548                 default:
 549                         (void)snprintf(msg + len, sizeof(msg) - len,
 550                             "UNKNOWN(%u).", (unsigned int)hio->hio_cmd);
 551                         break;
 552                 }
 553         }
 554         pjdlog_common(loglevel, debuglevel, error, "%s", msg);
 555 }
 556
 557 static int
 558 requnpack(struct hast_resource *res, struct hio *hio, struct nv *nv)
 559 {
 560
 561         hio->hio_cmd = nv_get_uint8(nv, "cmd");
 562         if (hio->hio_cmd == 0) {
 563                 pjdlog_error("Header contains no 'cmd' field.");
 564                 hio->hio_error = EINVAL;
 565                 goto end;
 566         }
 567         if (hio->hio_cmd != HIO_KEEPALIVE) {
 568                 hio->hio_seq = nv_get_uint64(nv, "seq");
 569                 if (hio->hio_seq == 0) {
 570                         pjdlog_error("Header contains no 'seq' field.");
 571                         hio->hio_error = EINVAL;
 572                         goto end;
 573                 }
 574         }
 575         switch (hio->hio_cmd) {
 576         case HIO_FLUSH:
 577         case HIO_KEEPALIVE:
 578                 break;
 579         case HIO_WRITE:
 580                 hio->hio_memsync = nv_exists(nv, "memsync");
 581                 /* FALLTHROUGH */
 582         case HIO_READ:
 583         case HIO_DELETE:
 584                 hio->hio_offset = nv_get_uint64(nv, "offset");
 585                 if (nv_error(nv) != 0) {
 586                         pjdlog_error("Header is missing 'offset' field.");
 587                         hio->hio_error = EINVAL;
 588                         goto end;
 589                 }
 590                 hio->hio_length = nv_get_uint64(nv, "length");
 591                 if (nv_error(nv) != 0) {
 592                         pjdlog_error("Header is missing 'length' field.");
 593                         hio->hio_error = EINVAL;
 594                         goto end;
 595                 }
 596                 if (hio->hio_length == 0) {
 597                         pjdlog_error("Data length is zero.");
 598                         hio->hio_error = EINVAL;
 599                         goto end;
 600                 }
 601                 if (hio->hio_cmd != HIO_DELETE && hio->hio_length > MAXPHYS) {
 602                         pjdlog_error("Data length is too large (%ju > %ju).",
 603                             (uintmax_t)hio->hio_length, (uintmax_t)MAXPHYS);
 604                         hio->hio_error = EINVAL;
 605                         goto end;
 606                 }
 607                 if ((hio->hio_offset % res->hr_local_sectorsize) != 0) {
 608                         pjdlog_error("Offset %ju is not multiple of sector size.",
 609                             (uintmax_t)hio->hio_offset);
 610                         hio->hio_error = EINVAL;
 611                         goto end;
 612                 }
 613                 if ((hio->hio_length % res->hr_local_sectorsize) != 0) {
 614                         pjdlog_error("Length %ju is not multiple of sector size.",
 615                             (uintmax_t)hio->hio_length);
 616                         hio->hio_error = EINVAL;
 617                         goto end;
 618                 }
 619                 if (hio->hio_offset + hio->hio_length >
 620                     (uint64_t)res->hr_datasize) {
 621                         pjdlog_error("Data offset is too large (%ju > %ju).",
 622                             (uintmax_t)(hio->hio_offset + hio->hio_length),
 623                             (uintmax_t)res->hr_datasize);
 624                         hio->hio_error = EINVAL;
 625                         goto end;
 626                 }
 627                 break;
 628         default:
 629                 pjdlog_error("Header contains invalid 'cmd' (%hhu).",
 630                     hio->hio_cmd);
 631                 hio->hio_error = EINVAL;
 632                 goto end;
 633         }
 634         hio->hio_error = 0;
 635 end:
 636         return (hio->hio_error);
 637 }
 638
 639 static __dead2 void
 640 secondary_exit(int exitcode, const char *fmt, ...)
 641 {
 642         va_list ap;
 643
 644         PJDLOG_ASSERT(exitcode != EX_OK);
 645         va_start(ap, fmt);
 646         pjdlogv_errno(LOG_ERR, fmt, ap);
 647         va_end(ap);
 648         event_send(gres, EVENT_DISCONNECT);
 649         exit(exitcode);
 650 }
 651
 652 /*
 653  * Thread receives requests from the primary node.
 654  */
 655 static void *
 656 recv_thread(void *arg)
 657 {
 658         struct hast_resource *res = arg;
 659         struct hio *hio, *mshio;
 660         struct nv *nv;
 661
 662         for (;;) {
 663                 pjdlog_debug(2, "recv: Taking free request.");
 664                 QUEUE_TAKE(free, hio);
 665                 pjdlog_debug(2, "recv: (%p) Got request.", hio);
 666                 if (hast_proto_recv_hdr(res->hr_remotein, &nv) == -1) {
 667                         secondary_exit(EX_TEMPFAIL,
 668                             "Unable to receive request header");
 669                 }
 670                 if (requnpack(res, hio, nv) != 0) {
 671                         nv_free(nv);
 672                         pjdlog_debug(2,
 673                             "recv: (%p) Moving request to the send queue.",
 674                             hio);
 675                         QUEUE_INSERT(send, hio);
 676                         continue;
 677                 }
 678                 switch (hio->hio_cmd) {
 679                 case HIO_READ:
 680                         res->hr_stat_read++;
 681                         break;
 682                 case HIO_WRITE:
 683                         res->hr_stat_write++;
 684                         break;
 685                 case HIO_DELETE:
 686                         res->hr_stat_delete++;
 687                         break;
 688                 case HIO_FLUSH:
 689                         res->hr_stat_flush++;
 690                         break;
 691                 case HIO_KEEPALIVE:
 692                         break;
 693                 default:
 694                         PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
 695                             hio->hio_cmd);
 696                 }
 697                 reqlog(LOG_DEBUG, 2, -1, hio,
 698                     "recv: (%p) Got request header: ", hio);
 699                 if (hio->hio_cmd == HIO_KEEPALIVE) {
 700                         nv_free(nv);
 701                         pjdlog_debug(2,
 702                             "recv: (%p) Moving request to the free queue.",
 703                             hio);
 704                         hio_clear(hio);
 705                         QUEUE_INSERT(free, hio);
 706                         continue;
 707                 } else if (hio->hio_cmd == HIO_WRITE) {
 708                         if (hast_proto_recv_data(res, res->hr_remotein, nv,
 709                             hio->hio_data, MAXPHYS) == -1) {
 710                                 secondary_exit(EX_TEMPFAIL,
 711                                     "Unable to receive request data");
 712                         }
 713                         if (hio->hio_memsync) {
 714                                 /*
 715                                  * For memsync requests we expect two replies.
 716                                  * Clone the hio so we can handle both of them.
 717                                  */
 718                                 pjdlog_debug(2, "recv: Taking free request.");
 719                                 QUEUE_TAKE(free, mshio);
 720                                 pjdlog_debug(2, "recv: (%p) Got request.",
 721                                     mshio);
 722                                 hio_copy(hio, mshio);
 723                                 mshio->hio_error = 0;
 724                                 /*
 725                                  * We want to keep 'memsync' tag only on the
 726                                  * request going onto send queue (mshio).
 727                                  */
 728                                 hio->hio_memsync = false;
 729                                 pjdlog_debug(2,
 730                                     "recv: (%p) Moving memsync request to the send queue.",
 731                                     mshio);
 732                                 QUEUE_INSERT(send, mshio);
 733                         }
 734                 }
 735                 nv_free(nv);
 736                 pjdlog_debug(2, "recv: (%p) Moving request to the disk queue.",
 737                     hio);
 738                 QUEUE_INSERT(disk, hio);
 739         }
 740         /* NOTREACHED */
 741         return (NULL);
 742 }
 743
 744 /*
 745  * Thread reads from or writes to local component and also handles DELETE and
 746  * FLUSH requests.
 747  */
 748 static void *
 749 disk_thread(void *arg)
 750 {
 751         struct hast_resource *res = arg;
 752         struct hio *hio;
 753         ssize_t ret;
 754         bool clear_activemap, logerror;
 755
 756         clear_activemap = true;
 757
 758         for (;;) {
 759                 pjdlog_debug(2, "disk: Taking request.");
 760                 QUEUE_TAKE(disk, hio);
 761                 while (clear_activemap) {
 762                         unsigned char *map;
 763                         size_t mapsize;
 764
 765                         /*
 766                          * When first request is received, it means that primary
 767                          * already received our activemap, merged it and stored
 768                          * locally. We can now safely clear our activemap.
 769                          */
 770                         mapsize =
 771                             activemap_calc_ondisk_size(res->hr_local_mediasize -
 772                             METADATA_SIZE, res->hr_extentsize,
 773                             res->hr_local_sectorsize);
 774                         map = calloc(1, mapsize);
 775                         if (map == NULL) {
 776                                 pjdlog_warning("Unable to allocate memory to clear local activemap.");
 777                                 break;
 778                         }
 779                         if (pwrite(res->hr_localfd, map, mapsize,
 780                             METADATA_SIZE) != (ssize_t)mapsize) {
 781                                 pjdlog_errno(LOG_WARNING,
 782                                     "Unable to store cleared activemap");
 783                                 free(map);
 784                                 res->hr_stat_activemap_write_error++;
 785                                 break;
 786                         }
 787                         free(map);
 788                         clear_activemap = false;
 789                         pjdlog_debug(1, "Local activemap cleared.");
 790                         break;
 791                 }
 792                 reqlog(LOG_DEBUG, 2, -1, hio, "disk: (%p) Got request: ", hio);
 793                 logerror = true;
 794                 /* Handle the actual request. */
 795                 switch (hio->hio_cmd) {
 796                 case HIO_READ:
 797                         ret = pread(res->hr_localfd, hio->hio_data,
 798                             hio->hio_length,
 799                             hio->hio_offset + res->hr_localoff);
 800                         if (ret == -1)
 801                                 hio->hio_error = errno;
 802                         else if (ret != (int64_t)hio->hio_length)
 803                                 hio->hio_error = EIO;
 804                         else
 805                                 hio->hio_error = 0;
 806                         break;
 807                 case HIO_WRITE:
 808                         ret = pwrite(res->hr_localfd, hio->hio_data,
 809                             hio->hio_length,
 810                             hio->hio_offset + res->hr_localoff);
 811                         if (ret == -1)
 812                                 hio->hio_error = errno;
 813                         else if (ret != (int64_t)hio->hio_length)
 814                                 hio->hio_error = EIO;
 815                         else
 816                                 hio->hio_error = 0;
 817                         break;
 818                 case HIO_DELETE:
 819                         ret = g_delete(res->hr_localfd,
 820                             hio->hio_offset + res->hr_localoff,
 821                             hio->hio_length);
 822                         if (ret == -1)
 823                                 hio->hio_error = errno;
 824                         else
 825                                 hio->hio_error = 0;
 826                         break;
 827                 case HIO_FLUSH:
 828                         if (!res->hr_localflush) {
 829                                 ret = -1;
 830                                 hio->hio_error = EOPNOTSUPP;
 831                                 logerror = false;
 832                                 break;
 833                         }
 834                         ret = g_flush(res->hr_localfd);
 835                         if (ret == -1) {
 836                                 if (errno == EOPNOTSUPP)
 837                                         res->hr_localflush = false;
 838                                 hio->hio_error = errno;
 839                         } else {
 840                                 hio->hio_error = 0;
 841                         }
 842                         break;
 843                 default:
 844                         PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
 845                             hio->hio_cmd);
 846                 }
 847                 if (logerror && hio->hio_error != 0) {
 848                         reqlog(LOG_ERR, 0, hio->hio_error, hio,
 849                             "Request failed: ");
 850                 }
 851                 pjdlog_debug(2, "disk: (%p) Moving request to the send queue.",
 852                     hio);
 853                 QUEUE_INSERT(send, hio);
 854         }
 855         /* NOTREACHED */
 856         return (NULL);
 857 }
 858
 859 /*
 860  * Thread sends requests back to primary node.
 861  */
 862 static void *
 863 send_thread(void *arg)
 864 {
 865         struct hast_resource *res = arg;
 866         struct nv *nvout;
 867         struct hio *hio;
 868         void *data;
 869         size_t length;
 870
 871         for (;;) {
 872                 pjdlog_debug(2, "send: Taking request.");
 873                 QUEUE_TAKE(send, hio);
 874                 reqlog(LOG_DEBUG, 2, -1, hio, "send: (%p) Got request: ", hio);
 875                 nvout = nv_alloc();
 876                 /* Copy sequence number. */
 877                 nv_add_uint64(nvout, hio->hio_seq, "seq");
 878                 if (hio->hio_memsync) {
 879                         PJDLOG_ASSERT(hio->hio_cmd == HIO_WRITE);
 880                         nv_add_int8(nvout, 1, "received");
 881                 }
 882                 switch (hio->hio_cmd) {
 883                 case HIO_READ:
 884                         if (hio->hio_error == 0) {
 885                                 data = hio->hio_data;
 886                                 length = hio->hio_length;
 887                                 break;
 888                         }
 889                         /*
 890                          * We send no data in case of an error.
 891                          */
 892                         /* FALLTHROUGH */
 893                 case HIO_DELETE:
 894                 case HIO_FLUSH:
 895                 case HIO_WRITE:
 896                         data = NULL;
 897                         length = 0;
 898                         break;
 899                 default:
 900                         PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
 901                             hio->hio_cmd);
 902                 }
 903                 if (hio->hio_error != 0) {
 904                         switch (hio->hio_cmd) {
 905                         case HIO_READ:
 906                                 res->hr_stat_read_error++;
 907                                 break;
 908                         case HIO_WRITE:
 909                                 res->hr_stat_write_error++;
 910                                 break;
 911                         case HIO_DELETE:
 912                                 res->hr_stat_delete_error++;
 913                                 break;
 914                         case HIO_FLUSH:
 915                                 res->hr_stat_flush_error++;
 916                                 break;
 917                         }
 918                         nv_add_int16(nvout, hio->hio_error, "error");
 919                 }
 920                 if (hast_proto_send(res, res->hr_remoteout, nvout, data,
 921                     length) == -1) {
 922                         secondary_exit(EX_TEMPFAIL, "Unable to send reply");
 923                 }
 924                 nv_free(nvout);
 925                 pjdlog_debug(2, "send: (%p) Moving request to the free queue.",
 926                     hio);
 927                 hio_clear(hio);
 928                 QUEUE_INSERT(free, hio);
 929         }
 930         /* NOTREACHED */
 931         return (NULL);
 932 }