freebsd-dev/sbin/hastd/primary.c
Pawel Jakub Dawidek e3feec94eb Correct typo.
MFC after:	3 days
2011-09-28 13:25:27 +00:00

2243 lines
61 KiB
C

/*-
* Copyright (c) 2009 The FreeBSD Foundation
* Copyright (c) 2010-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
* All rights reserved.
*
* This software was developed by Pawel Jakub Dawidek under sponsorship from
* the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/time.h>
#include <sys/bio.h>
#include <sys/disk.h>
#include <sys/refcount.h>
#include <sys/stat.h>
#include <geom/gate/g_gate.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <libgeom.h>
#include <pthread.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <activemap.h>
#include <nv.h>
#include <rangelock.h>
#include "control.h"
#include "event.h"
#include "hast.h"
#include "hast_proto.h"
#include "hastd.h"
#include "hooks.h"
#include "metadata.h"
#include "proto.h"
#include "pjdlog.h"
#include "subr.h"
#include "synch.h"
/* The is only one remote component for now. */
#define ISREMOTE(no) ((no) == 1)
struct hio {
/*
* Number of components we are still waiting for.
* When this field goes to 0, we can send the request back to the
* kernel. Each component has to decrease this counter by one
* even on failure.
*/
unsigned int hio_countdown;
/*
* Each component has a place to store its own error.
* Once the request is handled by all components we can decide if the
* request overall is successful or not.
*/
int *hio_errors;
/*
* Structure used to communicate with GEOM Gate class.
*/
struct g_gate_ctl_io hio_ggio;
TAILQ_ENTRY(hio) *hio_next;
};
#define hio_free_next hio_next[0]
#define hio_done_next hio_next[0]
/*
* Free list holds unused structures. When free list is empty, we have to wait
* until some in-progress requests are freed.
*/
static TAILQ_HEAD(, hio) hio_free_list;
static pthread_mutex_t hio_free_list_lock;
static pthread_cond_t hio_free_list_cond;
/*
* There is one send list for every component. One requests is placed on all
* send lists - each component gets the same request, but each component is
* responsible for managing his own send list.
*/
static TAILQ_HEAD(, hio) *hio_send_list;
static pthread_mutex_t *hio_send_list_lock;
static pthread_cond_t *hio_send_list_cond;
/*
* There is one recv list for every component, although local components don't
* use recv lists as local requests are done synchronously.
*/
static TAILQ_HEAD(, hio) *hio_recv_list;
static pthread_mutex_t *hio_recv_list_lock;
static pthread_cond_t *hio_recv_list_cond;
/*
* Request is placed on done list by the slowest component (the one that
* decreased hio_countdown from 1 to 0).
*/
static TAILQ_HEAD(, hio) hio_done_list;
static pthread_mutex_t hio_done_list_lock;
static pthread_cond_t hio_done_list_cond;
/*
* Structure below are for interaction with sync thread.
*/
static bool sync_inprogress;
static pthread_mutex_t sync_lock;
static pthread_cond_t sync_cond;
/*
* The lock below allows to synchornize access to remote connections.
*/
static pthread_rwlock_t *hio_remote_lock;
/*
* Lock to synchronize metadata updates. Also synchronize access to
* hr_primary_localcnt and hr_primary_remotecnt fields.
*/
static pthread_mutex_t metadata_lock;
/*
* Maximum number of outstanding I/O requests.
*/
#define HAST_HIO_MAX 256
/*
* Number of components. At this point there are only two components: local
* and remote, but in the future it might be possible to use multiple local
* and remote components.
*/
#define HAST_NCOMPONENTS 2
#define ISCONNECTED(res, no) \
((res)->hr_remotein != NULL && (res)->hr_remoteout != NULL)
#define QUEUE_INSERT1(hio, name, ncomp) do { \
bool _wakeup; \
\
mtx_lock(&hio_##name##_list_lock[(ncomp)]); \
_wakeup = TAILQ_EMPTY(&hio_##name##_list[(ncomp)]); \
TAILQ_INSERT_TAIL(&hio_##name##_list[(ncomp)], (hio), \
hio_next[(ncomp)]); \
mtx_unlock(&hio_##name##_list_lock[ncomp]); \
if (_wakeup) \
cv_signal(&hio_##name##_list_cond[(ncomp)]); \
} while (0)
#define QUEUE_INSERT2(hio, name) do { \
bool _wakeup; \
\
mtx_lock(&hio_##name##_list_lock); \
_wakeup = TAILQ_EMPTY(&hio_##name##_list); \
TAILQ_INSERT_TAIL(&hio_##name##_list, (hio), hio_##name##_next);\
mtx_unlock(&hio_##name##_list_lock); \
if (_wakeup) \
cv_signal(&hio_##name##_list_cond); \
} while (0)
#define QUEUE_TAKE1(hio, name, ncomp, timeout) do { \
bool _last; \
\
mtx_lock(&hio_##name##_list_lock[(ncomp)]); \
_last = false; \
while (((hio) = TAILQ_FIRST(&hio_##name##_list[(ncomp)])) == NULL && !_last) { \
cv_timedwait(&hio_##name##_list_cond[(ncomp)], \
&hio_##name##_list_lock[(ncomp)], (timeout)); \
if ((timeout) != 0) \
_last = true; \
} \
if (hio != NULL) { \
TAILQ_REMOVE(&hio_##name##_list[(ncomp)], (hio), \
hio_next[(ncomp)]); \
} \
mtx_unlock(&hio_##name##_list_lock[(ncomp)]); \
} while (0)
#define QUEUE_TAKE2(hio, name) do { \
mtx_lock(&hio_##name##_list_lock); \
while (((hio) = TAILQ_FIRST(&hio_##name##_list)) == NULL) { \
cv_wait(&hio_##name##_list_cond, \
&hio_##name##_list_lock); \
} \
TAILQ_REMOVE(&hio_##name##_list, (hio), hio_##name##_next); \
mtx_unlock(&hio_##name##_list_lock); \
} while (0)
#define SYNCREQ(hio) do { \
(hio)->hio_ggio.gctl_unit = -1; \
(hio)->hio_ggio.gctl_seq = 1; \
} while (0)
#define ISSYNCREQ(hio) ((hio)->hio_ggio.gctl_unit == -1)
#define SYNCREQDONE(hio) do { (hio)->hio_ggio.gctl_unit = -2; } while (0)
#define ISSYNCREQDONE(hio) ((hio)->hio_ggio.gctl_unit == -2)
static struct hast_resource *gres;
static pthread_mutex_t range_lock;
static struct rangelocks *range_regular;
static bool range_regular_wait;
static pthread_cond_t range_regular_cond;
static struct rangelocks *range_sync;
static bool range_sync_wait;
static pthread_cond_t range_sync_cond;
static bool fullystarted;
static void *ggate_recv_thread(void *arg);
static void *local_send_thread(void *arg);
static void *remote_send_thread(void *arg);
static void *remote_recv_thread(void *arg);
static void *ggate_send_thread(void *arg);
static void *sync_thread(void *arg);
static void *guard_thread(void *arg);
static void
cleanup(struct hast_resource *res)
{
int rerrno;
/* Remember errno. */
rerrno = errno;
/* Destroy ggate provider if we created one. */
if (res->hr_ggateunit >= 0) {
struct g_gate_ctl_destroy ggiod;
bzero(&ggiod, sizeof(ggiod));
ggiod.gctl_version = G_GATE_VERSION;
ggiod.gctl_unit = res->hr_ggateunit;
ggiod.gctl_force = 1;
if (ioctl(res->hr_ggatefd, G_GATE_CMD_DESTROY, &ggiod) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to destroy hast/%s device",
res->hr_provname);
}
res->hr_ggateunit = -1;
}
/* Restore errno. */
errno = rerrno;
}
static __dead2 void
primary_exit(int exitcode, const char *fmt, ...)
{
va_list ap;
PJDLOG_ASSERT(exitcode != EX_OK);
va_start(ap, fmt);
pjdlogv_errno(LOG_ERR, fmt, ap);
va_end(ap);
cleanup(gres);
exit(exitcode);
}
static __dead2 void
primary_exitx(int exitcode, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
pjdlogv(exitcode == EX_OK ? LOG_INFO : LOG_ERR, fmt, ap);
va_end(ap);
cleanup(gres);
exit(exitcode);
}
static int
hast_activemap_flush(struct hast_resource *res)
{
const unsigned char *buf;
size_t size;
buf = activemap_bitmap(res->hr_amp, &size);
PJDLOG_ASSERT(buf != NULL);
PJDLOG_ASSERT((size % res->hr_local_sectorsize) == 0);
if (pwrite(res->hr_localfd, buf, size, METADATA_SIZE) !=
(ssize_t)size) {
pjdlog_errno(LOG_ERR, "Unable to flush activemap to disk");
return (-1);
}
if (res->hr_metaflush == 1 && g_flush(res->hr_localfd) == -1) {
if (errno == EOPNOTSUPP) {
pjdlog_warning("The %s provider doesn't support flushing write cache. Disabling it.",
res->hr_localpath);
res->hr_metaflush = 0;
} else {
pjdlog_errno(LOG_ERR,
"Unable to flush disk cache on activemap update");
return (-1);
}
}
return (0);
}
static bool
real_remote(const struct hast_resource *res)
{
return (strcmp(res->hr_remoteaddr, "none") != 0);
}
static void
init_environment(struct hast_resource *res __unused)
{
struct hio *hio;
unsigned int ii, ncomps;
/*
* In the future it might be per-resource value.
*/
ncomps = HAST_NCOMPONENTS;
/*
* Allocate memory needed by lists.
*/
hio_send_list = malloc(sizeof(hio_send_list[0]) * ncomps);
if (hio_send_list == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for send lists.",
sizeof(hio_send_list[0]) * ncomps);
}
hio_send_list_lock = malloc(sizeof(hio_send_list_lock[0]) * ncomps);
if (hio_send_list_lock == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for send list locks.",
sizeof(hio_send_list_lock[0]) * ncomps);
}
hio_send_list_cond = malloc(sizeof(hio_send_list_cond[0]) * ncomps);
if (hio_send_list_cond == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for send list condition variables.",
sizeof(hio_send_list_cond[0]) * ncomps);
}
hio_recv_list = malloc(sizeof(hio_recv_list[0]) * ncomps);
if (hio_recv_list == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for recv lists.",
sizeof(hio_recv_list[0]) * ncomps);
}
hio_recv_list_lock = malloc(sizeof(hio_recv_list_lock[0]) * ncomps);
if (hio_recv_list_lock == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for recv list locks.",
sizeof(hio_recv_list_lock[0]) * ncomps);
}
hio_recv_list_cond = malloc(sizeof(hio_recv_list_cond[0]) * ncomps);
if (hio_recv_list_cond == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for recv list condition variables.",
sizeof(hio_recv_list_cond[0]) * ncomps);
}
hio_remote_lock = malloc(sizeof(hio_remote_lock[0]) * ncomps);
if (hio_remote_lock == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for remote connections locks.",
sizeof(hio_remote_lock[0]) * ncomps);
}
/*
* Initialize lists, their locks and theirs condition variables.
*/
TAILQ_INIT(&hio_free_list);
mtx_init(&hio_free_list_lock);
cv_init(&hio_free_list_cond);
for (ii = 0; ii < HAST_NCOMPONENTS; ii++) {
TAILQ_INIT(&hio_send_list[ii]);
mtx_init(&hio_send_list_lock[ii]);
cv_init(&hio_send_list_cond[ii]);
TAILQ_INIT(&hio_recv_list[ii]);
mtx_init(&hio_recv_list_lock[ii]);
cv_init(&hio_recv_list_cond[ii]);
rw_init(&hio_remote_lock[ii]);
}
TAILQ_INIT(&hio_done_list);
mtx_init(&hio_done_list_lock);
cv_init(&hio_done_list_cond);
mtx_init(&metadata_lock);
/*
* Allocate requests pool and initialize requests.
*/
for (ii = 0; ii < HAST_HIO_MAX; ii++) {
hio = malloc(sizeof(*hio));
if (hio == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for hio request.",
sizeof(*hio));
}
hio->hio_countdown = 0;
hio->hio_errors = malloc(sizeof(hio->hio_errors[0]) * ncomps);
if (hio->hio_errors == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable allocate %zu bytes of memory for hio errors.",
sizeof(hio->hio_errors[0]) * ncomps);
}
hio->hio_next = malloc(sizeof(hio->hio_next[0]) * ncomps);
if (hio->hio_next == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable allocate %zu bytes of memory for hio_next field.",
sizeof(hio->hio_next[0]) * ncomps);
}
hio->hio_ggio.gctl_version = G_GATE_VERSION;
hio->hio_ggio.gctl_data = malloc(MAXPHYS);
if (hio->hio_ggio.gctl_data == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate %zu bytes of memory for gctl_data.",
MAXPHYS);
}
hio->hio_ggio.gctl_length = MAXPHYS;
hio->hio_ggio.gctl_error = 0;
TAILQ_INSERT_HEAD(&hio_free_list, hio, hio_free_next);
}
}
static bool
init_resuid(struct hast_resource *res)
{
mtx_lock(&metadata_lock);
if (res->hr_resuid != 0) {
mtx_unlock(&metadata_lock);
return (false);
} else {
/* Initialize unique resource identifier. */
arc4random_buf(&res->hr_resuid, sizeof(res->hr_resuid));
mtx_unlock(&metadata_lock);
if (metadata_write(res) < 0)
exit(EX_NOINPUT);
return (true);
}
}
static void
init_local(struct hast_resource *res)
{
unsigned char *buf;
size_t mapsize;
if (metadata_read(res, true) < 0)
exit(EX_NOINPUT);
mtx_init(&res->hr_amp_lock);
if (activemap_init(&res->hr_amp, res->hr_datasize, res->hr_extentsize,
res->hr_local_sectorsize, res->hr_keepdirty) < 0) {
primary_exit(EX_TEMPFAIL, "Unable to create activemap");
}
mtx_init(&range_lock);
cv_init(&range_regular_cond);
if (rangelock_init(&range_regular) < 0)
primary_exit(EX_TEMPFAIL, "Unable to create regular range lock");
cv_init(&range_sync_cond);
if (rangelock_init(&range_sync) < 0)
primary_exit(EX_TEMPFAIL, "Unable to create sync range lock");
mapsize = activemap_ondisk_size(res->hr_amp);
buf = calloc(1, mapsize);
if (buf == NULL) {
primary_exitx(EX_TEMPFAIL,
"Unable to allocate buffer for activemap.");
}
if (pread(res->hr_localfd, buf, mapsize, METADATA_SIZE) !=
(ssize_t)mapsize) {
primary_exit(EX_NOINPUT, "Unable to read activemap");
}
activemap_copyin(res->hr_amp, buf, mapsize);
free(buf);
if (res->hr_resuid != 0)
return;
/*
* We're using provider for the first time. Initialize local and remote
* counters. We don't initialize resuid here, as we want to do it just
* in time. The reason for this is that we want to inform secondary
* that there were no writes yet, so there is no need to synchronize
* anything.
*/
res->hr_primary_localcnt = 0;
res->hr_primary_remotecnt = 0;
if (metadata_write(res) < 0)
exit(EX_NOINPUT);
}
static int
primary_connect(struct hast_resource *res, struct proto_conn **connp)
{
struct proto_conn *conn;
int16_t val;
val = 1;
if (proto_send(res->hr_conn, &val, sizeof(val)) < 0) {
primary_exit(EX_TEMPFAIL,
"Unable to send connection request to parent");
}
if (proto_recv(res->hr_conn, &val, sizeof(val)) < 0) {
primary_exit(EX_TEMPFAIL,
"Unable to receive reply to connection request from parent");
}
if (val != 0) {
errno = val;
pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
res->hr_remoteaddr);
return (-1);
}
if (proto_connection_recv(res->hr_conn, true, &conn) < 0) {
primary_exit(EX_TEMPFAIL,
"Unable to receive connection from parent");
}
if (proto_connect_wait(conn, res->hr_timeout) < 0) {
pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
res->hr_remoteaddr);
proto_close(conn);
return (-1);
}
/* Error in setting timeout is not critical, but why should it fail? */
if (proto_timeout(conn, res->hr_timeout) < 0)
pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
*connp = conn;
return (0);
}
static int
init_remote(struct hast_resource *res, struct proto_conn **inp,
struct proto_conn **outp)
{
struct proto_conn *in, *out;
struct nv *nvout, *nvin;
const unsigned char *token;
unsigned char *map;
const char *errmsg;
int32_t extentsize;
int64_t datasize;
uint32_t mapsize;
size_t size;
int error;
PJDLOG_ASSERT((inp == NULL && outp == NULL) || (inp != NULL && outp != NULL));
PJDLOG_ASSERT(real_remote(res));
in = out = NULL;
errmsg = NULL;
if (primary_connect(res, &out) == -1)
return (ECONNREFUSED);
error = ECONNABORTED;
/*
* First handshake step.
* Setup outgoing connection with remote node.
*/
nvout = nv_alloc();
nv_add_string(nvout, res->hr_name, "resource");
if (nv_error(nvout) != 0) {
pjdlog_common(LOG_WARNING, 0, nv_error(nvout),
"Unable to allocate header for connection with %s",
res->hr_remoteaddr);
nv_free(nvout);
goto close;
}
if (hast_proto_send(res, out, nvout, NULL, 0) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to send handshake header to %s",
res->hr_remoteaddr);
nv_free(nvout);
goto close;
}
nv_free(nvout);
if (hast_proto_recv_hdr(out, &nvin) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to receive handshake header from %s",
res->hr_remoteaddr);
goto close;
}
errmsg = nv_get_string(nvin, "errmsg");
if (errmsg != NULL) {
pjdlog_warning("%s", errmsg);
if (nv_exists(nvin, "wait"))
error = EBUSY;
nv_free(nvin);
goto close;
}
token = nv_get_uint8_array(nvin, &size, "token");
if (token == NULL) {
pjdlog_warning("Handshake header from %s has no 'token' field.",
res->hr_remoteaddr);
nv_free(nvin);
goto close;
}
if (size != sizeof(res->hr_token)) {
pjdlog_warning("Handshake header from %s contains 'token' of wrong size (got %zu, expected %zu).",
res->hr_remoteaddr, size, sizeof(res->hr_token));
nv_free(nvin);
goto close;
}
bcopy(token, res->hr_token, sizeof(res->hr_token));
nv_free(nvin);
/*
* Second handshake step.
* Setup incoming connection with remote node.
*/
if (primary_connect(res, &in) == -1)
goto close;
nvout = nv_alloc();
nv_add_string(nvout, res->hr_name, "resource");
nv_add_uint8_array(nvout, res->hr_token, sizeof(res->hr_token),
"token");
if (res->hr_resuid == 0) {
/*
* The resuid field was not yet initialized.
* Because we do synchronization inside init_resuid(), it is
* possible that someone already initialized it, the function
* will return false then, but if we successfully initialized
* it, we will get true. True means that there were no writes
* to this resource yet and we want to inform secondary that
* synchronization is not needed by sending "virgin" argument.
*/
if (init_resuid(res))
nv_add_int8(nvout, 1, "virgin");
}
nv_add_uint64(nvout, res->hr_resuid, "resuid");
nv_add_uint64(nvout, res->hr_primary_localcnt, "localcnt");
nv_add_uint64(nvout, res->hr_primary_remotecnt, "remotecnt");
if (nv_error(nvout) != 0) {
pjdlog_common(LOG_WARNING, 0, nv_error(nvout),
"Unable to allocate header for connection with %s",
res->hr_remoteaddr);
nv_free(nvout);
goto close;
}
if (hast_proto_send(res, in, nvout, NULL, 0) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to send handshake header to %s",
res->hr_remoteaddr);
nv_free(nvout);
goto close;
}
nv_free(nvout);
if (hast_proto_recv_hdr(out, &nvin) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to receive handshake header from %s",
res->hr_remoteaddr);
goto close;
}
errmsg = nv_get_string(nvin, "errmsg");
if (errmsg != NULL) {
pjdlog_warning("%s", errmsg);
nv_free(nvin);
goto close;
}
datasize = nv_get_int64(nvin, "datasize");
if (datasize != res->hr_datasize) {
pjdlog_warning("Data size differs between nodes (local=%jd, remote=%jd).",
(intmax_t)res->hr_datasize, (intmax_t)datasize);
nv_free(nvin);
goto close;
}
extentsize = nv_get_int32(nvin, "extentsize");
if (extentsize != res->hr_extentsize) {
pjdlog_warning("Extent size differs between nodes (local=%zd, remote=%zd).",
(ssize_t)res->hr_extentsize, (ssize_t)extentsize);
nv_free(nvin);
goto close;
}
res->hr_secondary_localcnt = nv_get_uint64(nvin, "localcnt");
res->hr_secondary_remotecnt = nv_get_uint64(nvin, "remotecnt");
res->hr_syncsrc = nv_get_uint8(nvin, "syncsrc");
if (nv_exists(nvin, "virgin")) {
/*
* Secondary was reinitialized, bump localcnt if it is 0 as
* only we have the data.
*/
PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_PRIMARY);
PJDLOG_ASSERT(res->hr_secondary_localcnt == 0);
if (res->hr_primary_localcnt == 0) {
PJDLOG_ASSERT(res->hr_secondary_remotecnt == 0);
mtx_lock(&metadata_lock);
res->hr_primary_localcnt++;
pjdlog_debug(1, "Increasing localcnt to %ju.",
(uintmax_t)res->hr_primary_localcnt);
(void)metadata_write(res);
mtx_unlock(&metadata_lock);
}
}
map = NULL;
mapsize = nv_get_uint32(nvin, "mapsize");
if (mapsize > 0) {
map = malloc(mapsize);
if (map == NULL) {
pjdlog_error("Unable to allocate memory for remote activemap (mapsize=%ju).",
(uintmax_t)mapsize);
nv_free(nvin);
goto close;
}
/*
* Remote node have some dirty extents on its own, lets
* download its activemap.
*/
if (hast_proto_recv_data(res, out, nvin, map,
mapsize) < 0) {
pjdlog_errno(LOG_ERR,
"Unable to receive remote activemap");
nv_free(nvin);
free(map);
goto close;
}
/*
* Merge local and remote bitmaps.
*/
activemap_merge(res->hr_amp, map, mapsize);
free(map);
/*
* Now that we merged bitmaps from both nodes, flush it to the
* disk before we start to synchronize.
*/
(void)hast_activemap_flush(res);
}
nv_free(nvin);
#ifdef notyet
/* Setup directions. */
if (proto_send(out, NULL, 0) == -1)
pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
if (proto_recv(in, NULL, 0) == -1)
pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
#endif
pjdlog_info("Connected to %s.", res->hr_remoteaddr);
if (inp != NULL && outp != NULL) {
*inp = in;
*outp = out;
} else {
res->hr_remotein = in;
res->hr_remoteout = out;
}
event_send(res, EVENT_CONNECT);
return (0);
close:
if (errmsg != NULL && strcmp(errmsg, "Split-brain condition!") == 0)
event_send(res, EVENT_SPLITBRAIN);
proto_close(out);
if (in != NULL)
proto_close(in);
return (error);
}
static void
sync_start(void)
{
mtx_lock(&sync_lock);
sync_inprogress = true;
mtx_unlock(&sync_lock);
cv_signal(&sync_cond);
}
static void
sync_stop(void)
{
mtx_lock(&sync_lock);
if (sync_inprogress)
sync_inprogress = false;
mtx_unlock(&sync_lock);
}
static void
init_ggate(struct hast_resource *res)
{
struct g_gate_ctl_create ggiocreate;
struct g_gate_ctl_cancel ggiocancel;
/*
* We communicate with ggate via /dev/ggctl. Open it.
*/
res->hr_ggatefd = open("/dev/" G_GATE_CTL_NAME, O_RDWR);
if (res->hr_ggatefd < 0)
primary_exit(EX_OSFILE, "Unable to open /dev/" G_GATE_CTL_NAME);
/*
* Create provider before trying to connect, as connection failure
* is not critical, but may take some time.
*/
bzero(&ggiocreate, sizeof(ggiocreate));
ggiocreate.gctl_version = G_GATE_VERSION;
ggiocreate.gctl_mediasize = res->hr_datasize;
ggiocreate.gctl_sectorsize = res->hr_local_sectorsize;
ggiocreate.gctl_flags = 0;
ggiocreate.gctl_maxcount = 0;
ggiocreate.gctl_timeout = 0;
ggiocreate.gctl_unit = G_GATE_NAME_GIVEN;
snprintf(ggiocreate.gctl_name, sizeof(ggiocreate.gctl_name), "hast/%s",
res->hr_provname);
if (ioctl(res->hr_ggatefd, G_GATE_CMD_CREATE, &ggiocreate) == 0) {
pjdlog_info("Device hast/%s created.", res->hr_provname);
res->hr_ggateunit = ggiocreate.gctl_unit;
return;
}
if (errno != EEXIST) {
primary_exit(EX_OSERR, "Unable to create hast/%s device",
res->hr_provname);
}
pjdlog_debug(1,
"Device hast/%s already exists, we will try to take it over.",
res->hr_provname);
/*
* If we received EEXIST, we assume that the process who created the
* provider died and didn't clean up. In that case we will start from
* where he left of.
*/
bzero(&ggiocancel, sizeof(ggiocancel));
ggiocancel.gctl_version = G_GATE_VERSION;
ggiocancel.gctl_unit = G_GATE_NAME_GIVEN;
snprintf(ggiocancel.gctl_name, sizeof(ggiocancel.gctl_name), "hast/%s",
res->hr_provname);
if (ioctl(res->hr_ggatefd, G_GATE_CMD_CANCEL, &ggiocancel) == 0) {
pjdlog_info("Device hast/%s recovered.", res->hr_provname);
res->hr_ggateunit = ggiocancel.gctl_unit;
return;
}
primary_exit(EX_OSERR, "Unable to take over hast/%s device",
res->hr_provname);
}
void
hastd_primary(struct hast_resource *res)
{
pthread_t td;
pid_t pid;
int error, mode, debuglevel;
/*
* Create communication channel for sending control commands from
* parent to child.
*/
if (proto_client(NULL, "socketpair://", &res->hr_ctrl) < 0) {
/* TODO: There's no need for this to be fatal error. */
KEEP_ERRNO((void)pidfile_remove(pfh));
pjdlog_exit(EX_OSERR,
"Unable to create control sockets between parent and child");
}
/*
* Create communication channel for sending events from child to parent.
*/
if (proto_client(NULL, "socketpair://", &res->hr_event) < 0) {
/* TODO: There's no need for this to be fatal error. */
KEEP_ERRNO((void)pidfile_remove(pfh));
pjdlog_exit(EX_OSERR,
"Unable to create event sockets between child and parent");
}
/*
* Create communication channel for sending connection requests from
* child to parent.
*/
if (proto_client(NULL, "socketpair://", &res->hr_conn) < 0) {
/* TODO: There's no need for this to be fatal error. */
KEEP_ERRNO((void)pidfile_remove(pfh));
pjdlog_exit(EX_OSERR,
"Unable to create connection sockets between child and parent");
}
pid = fork();
if (pid < 0) {
/* TODO: There's no need for this to be fatal error. */
KEEP_ERRNO((void)pidfile_remove(pfh));
pjdlog_exit(EX_TEMPFAIL, "Unable to fork");
}
if (pid > 0) {
/* This is parent. */
/* Declare that we are receiver. */
proto_recv(res->hr_event, NULL, 0);
proto_recv(res->hr_conn, NULL, 0);
/* Declare that we are sender. */
proto_send(res->hr_ctrl, NULL, 0);
res->hr_workerpid = pid;
return;
}
gres = res;
mode = pjdlog_mode_get();
debuglevel = pjdlog_debug_get();
/* Declare that we are sender. */
proto_send(res->hr_event, NULL, 0);
proto_send(res->hr_conn, NULL, 0);
/* Declare that we are receiver. */
proto_recv(res->hr_ctrl, NULL, 0);
descriptors_cleanup(res);
descriptors_assert(res, mode);
pjdlog_init(mode);
pjdlog_debug_set(debuglevel);
pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
setproctitle("%s (%s)", res->hr_name, role2str(res->hr_role));
init_local(res);
init_ggate(res);
init_environment(res);
if (drop_privs(res) != 0) {
cleanup(res);
exit(EX_CONFIG);
}
pjdlog_info("Privileges successfully dropped.");
/*
* Create the guard thread first, so we can handle signals from the
* very begining.
*/
error = pthread_create(&td, NULL, guard_thread, res);
PJDLOG_ASSERT(error == 0);
/*
* Create the control thread before sending any event to the parent,
* as we can deadlock when parent sends control request to worker,
* but worker has no control thread started yet, so parent waits.
* In the meantime worker sends an event to the parent, but parent
* is unable to handle the event, because it waits for control
* request response.
*/
error = pthread_create(&td, NULL, ctrl_thread, res);
PJDLOG_ASSERT(error == 0);
if (real_remote(res)) {
error = init_remote(res, NULL, NULL);
if (error == 0) {
sync_start();
} else if (error == EBUSY) {
time_t start = time(NULL);
pjdlog_warning("Waiting for remote node to become %s for %ds.",
role2str(HAST_ROLE_SECONDARY),
res->hr_timeout);
for (;;) {
sleep(1);
error = init_remote(res, NULL, NULL);
if (error != EBUSY)
break;
if (time(NULL) > start + res->hr_timeout)
break;
}
if (error == EBUSY) {
pjdlog_warning("Remote node is still %s, starting anyway.",
role2str(HAST_ROLE_PRIMARY));
}
}
}
error = pthread_create(&td, NULL, ggate_recv_thread, res);
PJDLOG_ASSERT(error == 0);
error = pthread_create(&td, NULL, local_send_thread, res);
PJDLOG_ASSERT(error == 0);
error = pthread_create(&td, NULL, remote_send_thread, res);
PJDLOG_ASSERT(error == 0);
error = pthread_create(&td, NULL, remote_recv_thread, res);
PJDLOG_ASSERT(error == 0);
error = pthread_create(&td, NULL, ggate_send_thread, res);
PJDLOG_ASSERT(error == 0);
fullystarted = true;
(void)sync_thread(res);
}
static void
reqlog(int loglevel, int debuglevel, struct g_gate_ctl_io *ggio, const char *fmt, ...)
{
char msg[1024];
va_list ap;
int len;
va_start(ap, fmt);
len = vsnprintf(msg, sizeof(msg), fmt, ap);
va_end(ap);
if ((size_t)len < sizeof(msg)) {
switch (ggio->gctl_cmd) {
case BIO_READ:
(void)snprintf(msg + len, sizeof(msg) - len,
"READ(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
(uintmax_t)ggio->gctl_length);
break;
case BIO_DELETE:
(void)snprintf(msg + len, sizeof(msg) - len,
"DELETE(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
(uintmax_t)ggio->gctl_length);
break;
case BIO_FLUSH:
(void)snprintf(msg + len, sizeof(msg) - len, "FLUSH.");
break;
case BIO_WRITE:
(void)snprintf(msg + len, sizeof(msg) - len,
"WRITE(%ju, %ju).", (uintmax_t)ggio->gctl_offset,
(uintmax_t)ggio->gctl_length);
break;
default:
(void)snprintf(msg + len, sizeof(msg) - len,
"UNKNOWN(%u).", (unsigned int)ggio->gctl_cmd);
break;
}
}
pjdlog_common(loglevel, debuglevel, -1, "%s", msg);
}
static void
remote_close(struct hast_resource *res, int ncomp)
{
rw_wlock(&hio_remote_lock[ncomp]);
/*
* A race is possible between dropping rlock and acquiring wlock -
* another thread can close connection in-between.
*/
if (!ISCONNECTED(res, ncomp)) {
PJDLOG_ASSERT(res->hr_remotein == NULL);
PJDLOG_ASSERT(res->hr_remoteout == NULL);
rw_unlock(&hio_remote_lock[ncomp]);
return;
}
PJDLOG_ASSERT(res->hr_remotein != NULL);
PJDLOG_ASSERT(res->hr_remoteout != NULL);
pjdlog_debug(2, "Closing incoming connection to %s.",
res->hr_remoteaddr);
proto_close(res->hr_remotein);
res->hr_remotein = NULL;
pjdlog_debug(2, "Closing outgoing connection to %s.",
res->hr_remoteaddr);
proto_close(res->hr_remoteout);
res->hr_remoteout = NULL;
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_warning("Disconnected from %s.", res->hr_remoteaddr);
/*
* Stop synchronization if in-progress.
*/
sync_stop();
event_send(res, EVENT_DISCONNECT);
}
/*
* Thread receives ggate I/O requests from the kernel and passes them to
* appropriate threads:
* WRITE - always goes to both local_send and remote_send threads
* READ (when the block is up-to-date on local component) -
* only local_send thread
* READ (when the block isn't up-to-date on local component) -
* only remote_send thread
* DELETE - always goes to both local_send and remote_send threads
* FLUSH - always goes to both local_send and remote_send threads
*/
static void *
ggate_recv_thread(void *arg)
{
struct hast_resource *res = arg;
struct g_gate_ctl_io *ggio;
struct hio *hio;
unsigned int ii, ncomp, ncomps;
int error;
ncomps = HAST_NCOMPONENTS;
for (;;) {
pjdlog_debug(2, "ggate_recv: Taking free request.");
QUEUE_TAKE2(hio, free);
pjdlog_debug(2, "ggate_recv: (%p) Got free request.", hio);
ggio = &hio->hio_ggio;
ggio->gctl_unit = res->hr_ggateunit;
ggio->gctl_length = MAXPHYS;
ggio->gctl_error = 0;
pjdlog_debug(2,
"ggate_recv: (%p) Waiting for request from the kernel.",
hio);
if (ioctl(res->hr_ggatefd, G_GATE_CMD_START, ggio) < 0) {
if (sigexit_received)
pthread_exit(NULL);
primary_exit(EX_OSERR, "G_GATE_CMD_START failed");
}
error = ggio->gctl_error;
switch (error) {
case 0:
break;
case ECANCELED:
/* Exit gracefully. */
if (!sigexit_received) {
pjdlog_debug(2,
"ggate_recv: (%p) Received cancel from the kernel.",
hio);
pjdlog_info("Received cancel from the kernel, exiting.");
}
pthread_exit(NULL);
case ENOMEM:
/*
* Buffer too small? Impossible, we allocate MAXPHYS
* bytes - request can't be bigger than that.
*/
/* FALLTHROUGH */
case ENXIO:
default:
primary_exitx(EX_OSERR, "G_GATE_CMD_START failed: %s.",
strerror(error));
}
for (ii = 0; ii < ncomps; ii++)
hio->hio_errors[ii] = EINVAL;
reqlog(LOG_DEBUG, 2, ggio,
"ggate_recv: (%p) Request received from the kernel: ",
hio);
/*
* Inform all components about new write request.
* For read request prefer local component unless the given
* range is out-of-date, then use remote component.
*/
switch (ggio->gctl_cmd) {
case BIO_READ:
res->hr_stat_read++;
pjdlog_debug(2,
"ggate_recv: (%p) Moving request to the send queue.",
hio);
refcount_init(&hio->hio_countdown, 1);
mtx_lock(&metadata_lock);
if (res->hr_syncsrc == HAST_SYNCSRC_UNDEF ||
res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
/*
* This range is up-to-date on local component,
* so handle request locally.
*/
/* Local component is 0 for now. */
ncomp = 0;
} else /* if (res->hr_syncsrc ==
HAST_SYNCSRC_SECONDARY) */ {
PJDLOG_ASSERT(res->hr_syncsrc ==
HAST_SYNCSRC_SECONDARY);
/*
* This range is out-of-date on local component,
* so send request to the remote node.
*/
/* Remote component is 1 for now. */
ncomp = 1;
}
mtx_unlock(&metadata_lock);
QUEUE_INSERT1(hio, send, ncomp);
break;
case BIO_WRITE:
res->hr_stat_write++;
if (res->hr_resuid == 0) {
/*
* This is first write, initialize localcnt and
* resuid.
*/
res->hr_primary_localcnt = 1;
(void)init_resuid(res);
}
for (;;) {
mtx_lock(&range_lock);
if (rangelock_islocked(range_sync,
ggio->gctl_offset, ggio->gctl_length)) {
pjdlog_debug(2,
"regular: Range offset=%jd length=%zu locked.",
(intmax_t)ggio->gctl_offset,
(size_t)ggio->gctl_length);
range_regular_wait = true;
cv_wait(&range_regular_cond, &range_lock);
range_regular_wait = false;
mtx_unlock(&range_lock);
continue;
}
if (rangelock_add(range_regular,
ggio->gctl_offset, ggio->gctl_length) < 0) {
mtx_unlock(&range_lock);
pjdlog_debug(2,
"regular: Range offset=%jd length=%zu is already locked, waiting.",
(intmax_t)ggio->gctl_offset,
(size_t)ggio->gctl_length);
sleep(1);
continue;
}
mtx_unlock(&range_lock);
break;
}
mtx_lock(&res->hr_amp_lock);
if (activemap_write_start(res->hr_amp,
ggio->gctl_offset, ggio->gctl_length)) {
res->hr_stat_activemap_update++;
(void)hast_activemap_flush(res);
}
mtx_unlock(&res->hr_amp_lock);
/* FALLTHROUGH */
case BIO_DELETE:
case BIO_FLUSH:
switch (ggio->gctl_cmd) {
case BIO_DELETE:
res->hr_stat_delete++;
break;
case BIO_FLUSH:
res->hr_stat_flush++;
break;
}
pjdlog_debug(2,
"ggate_recv: (%p) Moving request to the send queue.",
hio);
refcount_init(&hio->hio_countdown, ncomps);
for (ii = 0; ii < ncomps; ii++)
QUEUE_INSERT1(hio, send, ii);
break;
}
}
/* NOTREACHED */
return (NULL);
}
/*
* Thread reads from or writes to local component.
* If local read fails, it redirects it to remote_send thread.
*/
static void *
local_send_thread(void *arg)
{
struct hast_resource *res = arg;
struct g_gate_ctl_io *ggio;
struct hio *hio;
unsigned int ncomp, rncomp;
ssize_t ret;
/* Local component is 0 for now. */
ncomp = 0;
/* Remote component is 1 for now. */
rncomp = 1;
for (;;) {
pjdlog_debug(2, "local_send: Taking request.");
QUEUE_TAKE1(hio, send, ncomp, 0);
pjdlog_debug(2, "local_send: (%p) Got request.", hio);
ggio = &hio->hio_ggio;
switch (ggio->gctl_cmd) {
case BIO_READ:
ret = pread(res->hr_localfd, ggio->gctl_data,
ggio->gctl_length,
ggio->gctl_offset + res->hr_localoff);
if (ret == ggio->gctl_length)
hio->hio_errors[ncomp] = 0;
else if (!ISSYNCREQ(hio)) {
/*
* If READ failed, try to read from remote node.
*/
if (ret < 0) {
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%s), trying remote node. ",
strerror(errno));
} else if (ret != ggio->gctl_length) {
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%zd != %jd), trying remote node. ",
ret, (intmax_t)ggio->gctl_length);
}
QUEUE_INSERT1(hio, send, rncomp);
continue;
}
break;
case BIO_WRITE:
ret = pwrite(res->hr_localfd, ggio->gctl_data,
ggio->gctl_length,
ggio->gctl_offset + res->hr_localoff);
if (ret < 0) {
hio->hio_errors[ncomp] = errno;
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%s): ",
strerror(errno));
} else if (ret != ggio->gctl_length) {
hio->hio_errors[ncomp] = EIO;
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%zd != %jd): ",
ret, (intmax_t)ggio->gctl_length);
} else {
hio->hio_errors[ncomp] = 0;
}
break;
case BIO_DELETE:
ret = g_delete(res->hr_localfd,
ggio->gctl_offset + res->hr_localoff,
ggio->gctl_length);
if (ret < 0) {
hio->hio_errors[ncomp] = errno;
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%s): ",
strerror(errno));
} else {
hio->hio_errors[ncomp] = 0;
}
break;
case BIO_FLUSH:
if (!res->hr_localflush) {
ret = -1;
errno = EOPNOTSUPP;
break;
}
ret = g_flush(res->hr_localfd);
if (ret < 0) {
if (errno == EOPNOTSUPP)
res->hr_localflush = false;
hio->hio_errors[ncomp] = errno;
reqlog(LOG_WARNING, 0, ggio,
"Local request failed (%s): ",
strerror(errno));
} else {
hio->hio_errors[ncomp] = 0;
}
break;
}
if (refcount_release(&hio->hio_countdown)) {
if (ISSYNCREQ(hio)) {
mtx_lock(&sync_lock);
SYNCREQDONE(hio);
mtx_unlock(&sync_lock);
cv_signal(&sync_cond);
} else {
pjdlog_debug(2,
"local_send: (%p) Moving request to the done queue.",
hio);
QUEUE_INSERT2(hio, done);
}
}
}
/* NOTREACHED */
return (NULL);
}
static void
keepalive_send(struct hast_resource *res, unsigned int ncomp)
{
struct nv *nv;
rw_rlock(&hio_remote_lock[ncomp]);
if (!ISCONNECTED(res, ncomp)) {
rw_unlock(&hio_remote_lock[ncomp]);
return;
}
PJDLOG_ASSERT(res->hr_remotein != NULL);
PJDLOG_ASSERT(res->hr_remoteout != NULL);
nv = nv_alloc();
nv_add_uint8(nv, HIO_KEEPALIVE, "cmd");
if (nv_error(nv) != 0) {
rw_unlock(&hio_remote_lock[ncomp]);
nv_free(nv);
pjdlog_debug(1,
"keepalive_send: Unable to prepare header to send.");
return;
}
if (hast_proto_send(res, res->hr_remoteout, nv, NULL, 0) < 0) {
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_common(LOG_DEBUG, 1, errno,
"keepalive_send: Unable to send request");
nv_free(nv);
remote_close(res, ncomp);
return;
}
rw_unlock(&hio_remote_lock[ncomp]);
nv_free(nv);
pjdlog_debug(2, "keepalive_send: Request sent.");
}
/*
* Thread sends request to secondary node.
*/
static void *
remote_send_thread(void *arg)
{
struct hast_resource *res = arg;
struct g_gate_ctl_io *ggio;
time_t lastcheck, now;
struct hio *hio;
struct nv *nv;
unsigned int ncomp;
bool wakeup;
uint64_t offset, length;
uint8_t cmd;
void *data;
/* Remote component is 1 for now. */
ncomp = 1;
lastcheck = time(NULL);
for (;;) {
pjdlog_debug(2, "remote_send: Taking request.");
QUEUE_TAKE1(hio, send, ncomp, HAST_KEEPALIVE);
if (hio == NULL) {
now = time(NULL);
if (lastcheck + HAST_KEEPALIVE <= now) {
keepalive_send(res, ncomp);
lastcheck = now;
}
continue;
}
pjdlog_debug(2, "remote_send: (%p) Got request.", hio);
ggio = &hio->hio_ggio;
switch (ggio->gctl_cmd) {
case BIO_READ:
cmd = HIO_READ;
data = NULL;
offset = ggio->gctl_offset;
length = ggio->gctl_length;
break;
case BIO_WRITE:
cmd = HIO_WRITE;
data = ggio->gctl_data;
offset = ggio->gctl_offset;
length = ggio->gctl_length;
break;
case BIO_DELETE:
cmd = HIO_DELETE;
data = NULL;
offset = ggio->gctl_offset;
length = ggio->gctl_length;
break;
case BIO_FLUSH:
cmd = HIO_FLUSH;
data = NULL;
offset = 0;
length = 0;
break;
default:
PJDLOG_ABORT("invalid condition");
}
nv = nv_alloc();
nv_add_uint8(nv, cmd, "cmd");
nv_add_uint64(nv, (uint64_t)ggio->gctl_seq, "seq");
nv_add_uint64(nv, offset, "offset");
nv_add_uint64(nv, length, "length");
if (nv_error(nv) != 0) {
hio->hio_errors[ncomp] = nv_error(nv);
pjdlog_debug(2,
"remote_send: (%p) Unable to prepare header to send.",
hio);
reqlog(LOG_ERR, 0, ggio,
"Unable to prepare header to send (%s): ",
strerror(nv_error(nv)));
/* Move failed request immediately to the done queue. */
goto done_queue;
}
pjdlog_debug(2,
"remote_send: (%p) Moving request to the recv queue.",
hio);
/*
* Protect connection from disappearing.
*/
rw_rlock(&hio_remote_lock[ncomp]);
if (!ISCONNECTED(res, ncomp)) {
rw_unlock(&hio_remote_lock[ncomp]);
hio->hio_errors[ncomp] = ENOTCONN;
goto done_queue;
}
/*
* Move the request to recv queue before sending it, because
* in different order we can get reply before we move request
* to recv queue.
*/
mtx_lock(&hio_recv_list_lock[ncomp]);
wakeup = TAILQ_EMPTY(&hio_recv_list[ncomp]);
TAILQ_INSERT_TAIL(&hio_recv_list[ncomp], hio, hio_next[ncomp]);
mtx_unlock(&hio_recv_list_lock[ncomp]);
if (hast_proto_send(res, res->hr_remoteout, nv, data,
data != NULL ? length : 0) < 0) {
hio->hio_errors[ncomp] = errno;
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_debug(2,
"remote_send: (%p) Unable to send request.", hio);
reqlog(LOG_ERR, 0, ggio,
"Unable to send request (%s): ",
strerror(hio->hio_errors[ncomp]));
remote_close(res, ncomp);
/*
* Take request back from the receive queue and move
* it immediately to the done queue.
*/
mtx_lock(&hio_recv_list_lock[ncomp]);
TAILQ_REMOVE(&hio_recv_list[ncomp], hio, hio_next[ncomp]);
mtx_unlock(&hio_recv_list_lock[ncomp]);
goto done_queue;
}
rw_unlock(&hio_remote_lock[ncomp]);
nv_free(nv);
if (wakeup)
cv_signal(&hio_recv_list_cond[ncomp]);
continue;
done_queue:
nv_free(nv);
if (ISSYNCREQ(hio)) {
if (!refcount_release(&hio->hio_countdown))
continue;
mtx_lock(&sync_lock);
SYNCREQDONE(hio);
mtx_unlock(&sync_lock);
cv_signal(&sync_cond);
continue;
}
if (ggio->gctl_cmd == BIO_WRITE) {
mtx_lock(&res->hr_amp_lock);
if (activemap_need_sync(res->hr_amp, ggio->gctl_offset,
ggio->gctl_length)) {
(void)hast_activemap_flush(res);
}
mtx_unlock(&res->hr_amp_lock);
}
if (!refcount_release(&hio->hio_countdown))
continue;
pjdlog_debug(2,
"remote_send: (%p) Moving request to the done queue.",
hio);
QUEUE_INSERT2(hio, done);
}
/* NOTREACHED */
return (NULL);
}
/*
* Thread receives answer from secondary node and passes it to ggate_send
* thread.
*/
static void *
remote_recv_thread(void *arg)
{
struct hast_resource *res = arg;
struct g_gate_ctl_io *ggio;
struct hio *hio;
struct nv *nv;
unsigned int ncomp;
uint64_t seq;
int error;
/* Remote component is 1 for now. */
ncomp = 1;
for (;;) {
/* Wait until there is anything to receive. */
mtx_lock(&hio_recv_list_lock[ncomp]);
while (TAILQ_EMPTY(&hio_recv_list[ncomp])) {
pjdlog_debug(2, "remote_recv: No requests, waiting.");
cv_wait(&hio_recv_list_cond[ncomp],
&hio_recv_list_lock[ncomp]);
}
mtx_unlock(&hio_recv_list_lock[ncomp]);
rw_rlock(&hio_remote_lock[ncomp]);
if (!ISCONNECTED(res, ncomp)) {
rw_unlock(&hio_remote_lock[ncomp]);
/*
* Connection is dead, so move all pending requests to
* the done queue (one-by-one).
*/
mtx_lock(&hio_recv_list_lock[ncomp]);
hio = TAILQ_FIRST(&hio_recv_list[ncomp]);
PJDLOG_ASSERT(hio != NULL);
TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
hio_next[ncomp]);
mtx_unlock(&hio_recv_list_lock[ncomp]);
goto done_queue;
}
if (hast_proto_recv_hdr(res->hr_remotein, &nv) < 0) {
pjdlog_errno(LOG_ERR,
"Unable to receive reply header");
rw_unlock(&hio_remote_lock[ncomp]);
remote_close(res, ncomp);
continue;
}
rw_unlock(&hio_remote_lock[ncomp]);
seq = nv_get_uint64(nv, "seq");
if (seq == 0) {
pjdlog_error("Header contains no 'seq' field.");
nv_free(nv);
continue;
}
mtx_lock(&hio_recv_list_lock[ncomp]);
TAILQ_FOREACH(hio, &hio_recv_list[ncomp], hio_next[ncomp]) {
if (hio->hio_ggio.gctl_seq == seq) {
TAILQ_REMOVE(&hio_recv_list[ncomp], hio,
hio_next[ncomp]);
break;
}
}
mtx_unlock(&hio_recv_list_lock[ncomp]);
if (hio == NULL) {
pjdlog_error("Found no request matching received 'seq' field (%ju).",
(uintmax_t)seq);
nv_free(nv);
continue;
}
error = nv_get_int16(nv, "error");
if (error != 0) {
/* Request failed on remote side. */
hio->hio_errors[ncomp] = error;
reqlog(LOG_WARNING, 0, &hio->hio_ggio,
"Remote request failed (%s): ", strerror(error));
nv_free(nv);
goto done_queue;
}
ggio = &hio->hio_ggio;
switch (ggio->gctl_cmd) {
case BIO_READ:
rw_rlock(&hio_remote_lock[ncomp]);
if (!ISCONNECTED(res, ncomp)) {
rw_unlock(&hio_remote_lock[ncomp]);
nv_free(nv);
goto done_queue;
}
if (hast_proto_recv_data(res, res->hr_remotein, nv,
ggio->gctl_data, ggio->gctl_length) < 0) {
hio->hio_errors[ncomp] = errno;
pjdlog_errno(LOG_ERR,
"Unable to receive reply data");
rw_unlock(&hio_remote_lock[ncomp]);
nv_free(nv);
remote_close(res, ncomp);
goto done_queue;
}
rw_unlock(&hio_remote_lock[ncomp]);
break;
case BIO_WRITE:
case BIO_DELETE:
case BIO_FLUSH:
break;
default:
PJDLOG_ABORT("invalid condition");
}
hio->hio_errors[ncomp] = 0;
nv_free(nv);
done_queue:
if (refcount_release(&hio->hio_countdown)) {
if (ISSYNCREQ(hio)) {
mtx_lock(&sync_lock);
SYNCREQDONE(hio);
mtx_unlock(&sync_lock);
cv_signal(&sync_cond);
} else {
pjdlog_debug(2,
"remote_recv: (%p) Moving request to the done queue.",
hio);
QUEUE_INSERT2(hio, done);
}
}
}
/* NOTREACHED */
return (NULL);
}
/*
* Thread sends answer to the kernel.
*/
static void *
ggate_send_thread(void *arg)
{
struct hast_resource *res = arg;
struct g_gate_ctl_io *ggio;
struct hio *hio;
unsigned int ii, ncomp, ncomps;
ncomps = HAST_NCOMPONENTS;
for (;;) {
pjdlog_debug(2, "ggate_send: Taking request.");
QUEUE_TAKE2(hio, done);
pjdlog_debug(2, "ggate_send: (%p) Got request.", hio);
ggio = &hio->hio_ggio;
for (ii = 0; ii < ncomps; ii++) {
if (hio->hio_errors[ii] == 0) {
/*
* One successful request is enough to declare
* success.
*/
ggio->gctl_error = 0;
break;
}
}
if (ii == ncomps) {
/*
* None of the requests were successful.
* Use the error from local component except the
* case when we did only remote request.
*/
if (ggio->gctl_cmd == BIO_READ &&
res->hr_syncsrc == HAST_SYNCSRC_SECONDARY)
ggio->gctl_error = hio->hio_errors[1];
else
ggio->gctl_error = hio->hio_errors[0];
}
if (ggio->gctl_error == 0 && ggio->gctl_cmd == BIO_WRITE) {
mtx_lock(&res->hr_amp_lock);
if (activemap_write_complete(res->hr_amp,
ggio->gctl_offset, ggio->gctl_length)) {
res->hr_stat_activemap_update++;
(void)hast_activemap_flush(res);
}
mtx_unlock(&res->hr_amp_lock);
}
if (ggio->gctl_cmd == BIO_WRITE) {
/*
* Unlock range we locked.
*/
mtx_lock(&range_lock);
rangelock_del(range_regular, ggio->gctl_offset,
ggio->gctl_length);
if (range_sync_wait)
cv_signal(&range_sync_cond);
mtx_unlock(&range_lock);
/*
* Bump local count if this is first write after
* connection failure with remote node.
*/
ncomp = 1;
rw_rlock(&hio_remote_lock[ncomp]);
if (!ISCONNECTED(res, ncomp)) {
mtx_lock(&metadata_lock);
if (res->hr_primary_localcnt ==
res->hr_secondary_remotecnt) {
res->hr_primary_localcnt++;
pjdlog_debug(1,
"Increasing localcnt to %ju.",
(uintmax_t)res->hr_primary_localcnt);
(void)metadata_write(res);
}
mtx_unlock(&metadata_lock);
}
rw_unlock(&hio_remote_lock[ncomp]);
}
if (ioctl(res->hr_ggatefd, G_GATE_CMD_DONE, ggio) < 0)
primary_exit(EX_OSERR, "G_GATE_CMD_DONE failed");
pjdlog_debug(2,
"ggate_send: (%p) Moving request to the free queue.", hio);
QUEUE_INSERT2(hio, free);
}
/* NOTREACHED */
return (NULL);
}
/*
* Thread synchronize local and remote components.
*/
static void *
sync_thread(void *arg __unused)
{
struct hast_resource *res = arg;
struct hio *hio;
struct g_gate_ctl_io *ggio;
struct timeval tstart, tend, tdiff;
unsigned int ii, ncomp, ncomps;
off_t offset, length, synced;
bool dorewind;
int syncext;
ncomps = HAST_NCOMPONENTS;
dorewind = true;
synced = 0;
offset = -1;
for (;;) {
mtx_lock(&sync_lock);
if (offset >= 0 && !sync_inprogress) {
gettimeofday(&tend, NULL);
timersub(&tend, &tstart, &tdiff);
pjdlog_info("Synchronization interrupted after %#.0T. "
"%NB synchronized so far.", &tdiff,
(intmax_t)synced);
event_send(res, EVENT_SYNCINTR);
}
while (!sync_inprogress) {
dorewind = true;
synced = 0;
cv_wait(&sync_cond, &sync_lock);
}
mtx_unlock(&sync_lock);
/*
* Obtain offset at which we should synchronize.
* Rewind synchronization if needed.
*/
mtx_lock(&res->hr_amp_lock);
if (dorewind)
activemap_sync_rewind(res->hr_amp);
offset = activemap_sync_offset(res->hr_amp, &length, &syncext);
if (syncext != -1) {
/*
* We synchronized entire syncext extent, we can mark
* it as clean now.
*/
if (activemap_extent_complete(res->hr_amp, syncext))
(void)hast_activemap_flush(res);
}
mtx_unlock(&res->hr_amp_lock);
if (dorewind) {
dorewind = false;
if (offset < 0)
pjdlog_info("Nodes are in sync.");
else {
pjdlog_info("Synchronization started. %NB to go.",
(intmax_t)(res->hr_extentsize *
activemap_ndirty(res->hr_amp)));
event_send(res, EVENT_SYNCSTART);
gettimeofday(&tstart, NULL);
}
}
if (offset < 0) {
sync_stop();
pjdlog_debug(1, "Nothing to synchronize.");
/*
* Synchronization complete, make both localcnt and
* remotecnt equal.
*/
ncomp = 1;
rw_rlock(&hio_remote_lock[ncomp]);
if (ISCONNECTED(res, ncomp)) {
if (synced > 0) {
int64_t bps;
gettimeofday(&tend, NULL);
timersub(&tend, &tstart, &tdiff);
bps = (int64_t)((double)synced /
((double)tdiff.tv_sec +
(double)tdiff.tv_usec / 1000000));
pjdlog_info("Synchronization complete. "
"%NB synchronized in %#.0lT (%NB/sec).",
(intmax_t)synced, &tdiff,
(intmax_t)bps);
event_send(res, EVENT_SYNCDONE);
}
mtx_lock(&metadata_lock);
res->hr_syncsrc = HAST_SYNCSRC_UNDEF;
res->hr_primary_localcnt =
res->hr_secondary_remotecnt;
res->hr_primary_remotecnt =
res->hr_secondary_localcnt;
pjdlog_debug(1,
"Setting localcnt to %ju and remotecnt to %ju.",
(uintmax_t)res->hr_primary_localcnt,
(uintmax_t)res->hr_primary_remotecnt);
(void)metadata_write(res);
mtx_unlock(&metadata_lock);
}
rw_unlock(&hio_remote_lock[ncomp]);
continue;
}
pjdlog_debug(2, "sync: Taking free request.");
QUEUE_TAKE2(hio, free);
pjdlog_debug(2, "sync: (%p) Got free request.", hio);
/*
* Lock the range we are going to synchronize. We don't want
* race where someone writes between our read and write.
*/
for (;;) {
mtx_lock(&range_lock);
if (rangelock_islocked(range_regular, offset, length)) {
pjdlog_debug(2,
"sync: Range offset=%jd length=%jd locked.",
(intmax_t)offset, (intmax_t)length);
range_sync_wait = true;
cv_wait(&range_sync_cond, &range_lock);
range_sync_wait = false;
mtx_unlock(&range_lock);
continue;
}
if (rangelock_add(range_sync, offset, length) < 0) {
mtx_unlock(&range_lock);
pjdlog_debug(2,
"sync: Range offset=%jd length=%jd is already locked, waiting.",
(intmax_t)offset, (intmax_t)length);
sleep(1);
continue;
}
mtx_unlock(&range_lock);
break;
}
/*
* First read the data from synchronization source.
*/
SYNCREQ(hio);
ggio = &hio->hio_ggio;
ggio->gctl_cmd = BIO_READ;
ggio->gctl_offset = offset;
ggio->gctl_length = length;
ggio->gctl_error = 0;
for (ii = 0; ii < ncomps; ii++)
hio->hio_errors[ii] = EINVAL;
reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
hio);
pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
hio);
mtx_lock(&metadata_lock);
if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
/*
* This range is up-to-date on local component,
* so handle request locally.
*/
/* Local component is 0 for now. */
ncomp = 0;
} else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
/*
* This range is out-of-date on local component,
* so send request to the remote node.
*/
/* Remote component is 1 for now. */
ncomp = 1;
}
mtx_unlock(&metadata_lock);
refcount_init(&hio->hio_countdown, 1);
QUEUE_INSERT1(hio, send, ncomp);
/*
* Let's wait for READ to finish.
*/
mtx_lock(&sync_lock);
while (!ISSYNCREQDONE(hio))
cv_wait(&sync_cond, &sync_lock);
mtx_unlock(&sync_lock);
if (hio->hio_errors[ncomp] != 0) {
pjdlog_error("Unable to read synchronization data: %s.",
strerror(hio->hio_errors[ncomp]));
goto free_queue;
}
/*
* We read the data from synchronization source, now write it
* to synchronization target.
*/
SYNCREQ(hio);
ggio->gctl_cmd = BIO_WRITE;
for (ii = 0; ii < ncomps; ii++)
hio->hio_errors[ii] = EINVAL;
reqlog(LOG_DEBUG, 2, ggio, "sync: (%p) Sending sync request: ",
hio);
pjdlog_debug(2, "sync: (%p) Moving request to the send queue.",
hio);
mtx_lock(&metadata_lock);
if (res->hr_syncsrc == HAST_SYNCSRC_PRIMARY) {
/*
* This range is up-to-date on local component,
* so we update remote component.
*/
/* Remote component is 1 for now. */
ncomp = 1;
} else /* if (res->hr_syncsrc == HAST_SYNCSRC_SECONDARY) */ {
PJDLOG_ASSERT(res->hr_syncsrc == HAST_SYNCSRC_SECONDARY);
/*
* This range is out-of-date on local component,
* so we update it.
*/
/* Local component is 0 for now. */
ncomp = 0;
}
mtx_unlock(&metadata_lock);
pjdlog_debug(2, "sync: (%p) Moving request to the send queues.",
hio);
refcount_init(&hio->hio_countdown, 1);
QUEUE_INSERT1(hio, send, ncomp);
/*
* Let's wait for WRITE to finish.
*/
mtx_lock(&sync_lock);
while (!ISSYNCREQDONE(hio))
cv_wait(&sync_cond, &sync_lock);
mtx_unlock(&sync_lock);
if (hio->hio_errors[ncomp] != 0) {
pjdlog_error("Unable to write synchronization data: %s.",
strerror(hio->hio_errors[ncomp]));
goto free_queue;
}
synced += length;
free_queue:
mtx_lock(&range_lock);
rangelock_del(range_sync, offset, length);
if (range_regular_wait)
cv_signal(&range_regular_cond);
mtx_unlock(&range_lock);
pjdlog_debug(2, "sync: (%p) Moving request to the free queue.",
hio);
QUEUE_INSERT2(hio, free);
}
/* NOTREACHED */
return (NULL);
}
void
primary_config_reload(struct hast_resource *res, struct nv *nv)
{
unsigned int ii, ncomps;
int modified, vint;
const char *vstr;
pjdlog_info("Reloading configuration...");
PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
PJDLOG_ASSERT(gres == res);
nv_assert(nv, "remoteaddr");
nv_assert(nv, "sourceaddr");
nv_assert(nv, "replication");
nv_assert(nv, "checksum");
nv_assert(nv, "compression");
nv_assert(nv, "timeout");
nv_assert(nv, "exec");
nv_assert(nv, "metaflush");
ncomps = HAST_NCOMPONENTS;
#define MODIFIED_REMOTEADDR 0x01
#define MODIFIED_SOURCEADDR 0x02
#define MODIFIED_REPLICATION 0x04
#define MODIFIED_CHECKSUM 0x08
#define MODIFIED_COMPRESSION 0x10
#define MODIFIED_TIMEOUT 0x20
#define MODIFIED_EXEC 0x40
#define MODIFIED_METAFLUSH 0x80
modified = 0;
vstr = nv_get_string(nv, "remoteaddr");
if (strcmp(gres->hr_remoteaddr, vstr) != 0) {
/*
* Don't copy res->hr_remoteaddr to gres just yet.
* We want remote_close() to log disconnect from the old
* addresses, not from the new ones.
*/
modified |= MODIFIED_REMOTEADDR;
}
vstr = nv_get_string(nv, "sourceaddr");
if (strcmp(gres->hr_sourceaddr, vstr) != 0) {
strlcpy(gres->hr_sourceaddr, vstr, sizeof(gres->hr_sourceaddr));
modified |= MODIFIED_SOURCEADDR;
}
vint = nv_get_int32(nv, "replication");
if (gres->hr_replication != vint) {
gres->hr_replication = vint;
modified |= MODIFIED_REPLICATION;
}
vint = nv_get_int32(nv, "checksum");
if (gres->hr_checksum != vint) {
gres->hr_checksum = vint;
modified |= MODIFIED_CHECKSUM;
}
vint = nv_get_int32(nv, "compression");
if (gres->hr_compression != vint) {
gres->hr_compression = vint;
modified |= MODIFIED_COMPRESSION;
}
vint = nv_get_int32(nv, "timeout");
if (gres->hr_timeout != vint) {
gres->hr_timeout = vint;
modified |= MODIFIED_TIMEOUT;
}
vstr = nv_get_string(nv, "exec");
if (strcmp(gres->hr_exec, vstr) != 0) {
strlcpy(gres->hr_exec, vstr, sizeof(gres->hr_exec));
modified |= MODIFIED_EXEC;
}
vint = nv_get_int32(nv, "metaflush");
if (gres->hr_metaflush != vint) {
gres->hr_metaflush = vint;
modified |= MODIFIED_METAFLUSH;
}
/*
* Change timeout for connected sockets.
* Don't bother if we need to reconnect.
*/
if ((modified & MODIFIED_TIMEOUT) != 0 &&
(modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR |
MODIFIED_REPLICATION)) == 0) {
for (ii = 0; ii < ncomps; ii++) {
if (!ISREMOTE(ii))
continue;
rw_rlock(&hio_remote_lock[ii]);
if (!ISCONNECTED(gres, ii)) {
rw_unlock(&hio_remote_lock[ii]);
continue;
}
rw_unlock(&hio_remote_lock[ii]);
if (proto_timeout(gres->hr_remotein,
gres->hr_timeout) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to set connection timeout");
}
if (proto_timeout(gres->hr_remoteout,
gres->hr_timeout) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to set connection timeout");
}
}
}
if ((modified & (MODIFIED_REMOTEADDR | MODIFIED_SOURCEADDR |
MODIFIED_REPLICATION)) != 0) {
for (ii = 0; ii < ncomps; ii++) {
if (!ISREMOTE(ii))
continue;
remote_close(gres, ii);
}
if (modified & MODIFIED_REMOTEADDR) {
vstr = nv_get_string(nv, "remoteaddr");
strlcpy(gres->hr_remoteaddr, vstr,
sizeof(gres->hr_remoteaddr));
}
}
#undef MODIFIED_REMOTEADDR
#undef MODIFIED_SOURCEADDR
#undef MODIFIED_REPLICATION
#undef MODIFIED_CHECKSUM
#undef MODIFIED_COMPRESSION
#undef MODIFIED_TIMEOUT
#undef MODIFIED_EXEC
#undef MODIFIED_METAFLUSH
pjdlog_info("Configuration reloaded successfully.");
}
static void
guard_one(struct hast_resource *res, unsigned int ncomp)
{
struct proto_conn *in, *out;
if (!ISREMOTE(ncomp))
return;
rw_rlock(&hio_remote_lock[ncomp]);
if (!real_remote(res)) {
rw_unlock(&hio_remote_lock[ncomp]);
return;
}
if (ISCONNECTED(res, ncomp)) {
PJDLOG_ASSERT(res->hr_remotein != NULL);
PJDLOG_ASSERT(res->hr_remoteout != NULL);
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_debug(2, "remote_guard: Connection to %s is ok.",
res->hr_remoteaddr);
return;
}
PJDLOG_ASSERT(res->hr_remotein == NULL);
PJDLOG_ASSERT(res->hr_remoteout == NULL);
/*
* Upgrade the lock. It doesn't have to be atomic as no other thread
* can change connection status from disconnected to connected.
*/
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_debug(2, "remote_guard: Reconnecting to %s.",
res->hr_remoteaddr);
in = out = NULL;
if (init_remote(res, &in, &out) == 0) {
rw_wlock(&hio_remote_lock[ncomp]);
PJDLOG_ASSERT(res->hr_remotein == NULL);
PJDLOG_ASSERT(res->hr_remoteout == NULL);
PJDLOG_ASSERT(in != NULL && out != NULL);
res->hr_remotein = in;
res->hr_remoteout = out;
rw_unlock(&hio_remote_lock[ncomp]);
pjdlog_info("Successfully reconnected to %s.",
res->hr_remoteaddr);
sync_start();
} else {
/* Both connections should be NULL. */
PJDLOG_ASSERT(res->hr_remotein == NULL);
PJDLOG_ASSERT(res->hr_remoteout == NULL);
PJDLOG_ASSERT(in == NULL && out == NULL);
pjdlog_debug(2, "remote_guard: Reconnect to %s failed.",
res->hr_remoteaddr);
}
}
/*
* Thread guards remote connections and reconnects when needed, handles
* signals, etc.
*/
static void *
guard_thread(void *arg)
{
struct hast_resource *res = arg;
unsigned int ii, ncomps;
struct timespec timeout;
time_t lastcheck, now;
sigset_t mask;
int signo;
ncomps = HAST_NCOMPONENTS;
lastcheck = time(NULL);
PJDLOG_VERIFY(sigemptyset(&mask) == 0);
PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
timeout.tv_sec = HAST_KEEPALIVE;
timeout.tv_nsec = 0;
signo = -1;
for (;;) {
switch (signo) {
case SIGINT:
case SIGTERM:
sigexit_received = true;
primary_exitx(EX_OK,
"Termination signal received, exiting.");
break;
default:
break;
}
/*
* Don't check connections until we fully started,
* as we may still be looping, waiting for remote node
* to switch from primary to secondary.
*/
if (fullystarted) {
pjdlog_debug(2, "remote_guard: Checking connections.");
now = time(NULL);
if (lastcheck + HAST_KEEPALIVE <= now) {
for (ii = 0; ii < ncomps; ii++)
guard_one(res, ii);
lastcheck = now;
}
}
signo = sigtimedwait(&mask, NULL, &timeout);
}
/* NOTREACHED */
return (NULL);
}