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author | Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> | 2021-09-06 22:06:48 +0300 |
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committer | Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> | 2021-12-21 14:52:06 +0100 |
commit | be16b8bf9f231d19c172961d3327f9f72a7cd45f (patch) | |
tree | 6bfa8e130d20b56113bfe6652922d2e8c1090c75 /block/nbd.c | |
parent | 2bf40d0841b942e7ba12953d515e62a436f0af84 (diff) | |
download | qemu-be16b8bf9f231d19c172961d3327f9f72a7cd45f.zip qemu-be16b8bf9f231d19c172961d3327f9f72a7cd45f.tar.gz qemu-be16b8bf9f231d19c172961d3327f9f72a7cd45f.tar.bz2 |
nbd: allow reconnect on open, with corresponding new options
It is useful when start of vm and start of nbd server are not
simple to sync.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'block/nbd.c')
-rw-r--r-- | block/nbd.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/block/nbd.c b/block/nbd.c index 5ef462d..63dbfa8 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -80,6 +80,7 @@ typedef struct BDRVNBDState { NBDClientState state; QEMUTimer *reconnect_delay_timer; + QEMUTimer *open_timer; NBDClientRequest requests[MAX_NBD_REQUESTS]; NBDReply reply; @@ -87,6 +88,7 @@ typedef struct BDRVNBDState { /* Connection parameters */ uint32_t reconnect_delay; + uint32_t open_timeout; SocketAddress *saddr; char *export, *tlscredsid; QCryptoTLSCreds *tlscreds; @@ -218,6 +220,32 @@ static void nbd_teardown_connection(BlockDriverState *bs) s->state = NBD_CLIENT_QUIT; } +static void open_timer_del(BDRVNBDState *s) +{ + if (s->open_timer) { + timer_free(s->open_timer); + s->open_timer = NULL; + } +} + +static void open_timer_cb(void *opaque) +{ + BDRVNBDState *s = opaque; + + nbd_co_establish_connection_cancel(s->conn); + open_timer_del(s); +} + +static void open_timer_init(BDRVNBDState *s, uint64_t expire_time_ns) +{ + assert(!s->open_timer); + s->open_timer = aio_timer_new(bdrv_get_aio_context(s->bs), + QEMU_CLOCK_REALTIME, + SCALE_NS, + open_timer_cb, s); + timer_mod(s->open_timer, expire_time_ns); +} + static bool nbd_client_connecting(BDRVNBDState *s) { NBDClientState state = qatomic_load_acquire(&s->state); @@ -1742,6 +1770,15 @@ static QemuOptsList nbd_runtime_opts = { "future requests before a successful reconnect will " "immediately fail. Default 0", }, + { + .name = "open-timeout", + .type = QEMU_OPT_NUMBER, + .help = "In seconds. If zero, the nbd driver tries the connection " + "only once, and fails to open if the connection fails. " + "If non-zero, the nbd driver will repeat connection " + "attempts until successful or until @open-timeout seconds " + "have elapsed. Default 0", + }, { /* end of list */ } }, }; @@ -1797,6 +1834,7 @@ static int nbd_process_options(BlockDriverState *bs, QDict *options, } s->reconnect_delay = qemu_opt_get_number(opts, "reconnect-delay", 0); + s->open_timeout = qemu_opt_get_number(opts, "open-timeout", 0); ret = 0; @@ -1828,7 +1866,12 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, s->conn = nbd_client_connection_new(s->saddr, true, s->export, s->x_dirty_bitmap, s->tlscreds); - /* TODO: Configurable retry-until-timeout behaviour. */ + if (s->open_timeout) { + nbd_client_connection_enable_retry(s->conn); + open_timer_init(s, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + + s->open_timeout * NANOSECONDS_PER_SECOND); + } + s->state = NBD_CLIENT_CONNECTING_WAIT; ret = nbd_do_establish_connection(bs, errp); if (ret < 0) { |