Add two parameters:
reconnect-attempts, which defines maximum number of reconnects, after
which:
- open will fail
- block operations will fail
Note: on open, we actually have reconnect-attempts+1 connection
attempts, the first one is not REconnect.
reconnect-timeout, timeout in nanoseconds between reconnects.
Realization of these options is in the following patch.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
qapi/block-core.json | 12 +++++++++++-
block/nbd-client.h | 2 ++
block/nbd-client.c | 13 +++++++++++++
block/nbd.c | 22 +++++++++++++++++++++-
4 files changed, 47 insertions(+), 2 deletions(-)
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 4b1de474a9..4abba9d38e 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -3356,12 +3356,22 @@
#
# @tls-creds: TLS credentials ID
#
+# @reconnect-attempts: number of connection attempts on disconnect.
+# Must be >= 0. Default is 0. On nbd disk open, there
would
+# be maximum of @reconnect-attempts + 1 total tries to
+# connect
+#
+# @reconnect-timeout: timeout between reconnect attempts in nanoseconds.
Default
+# is 1000000000 (one second)
+#
# Since: 2.9
##
{ 'struct': 'BlockdevOptionsNbd',
'data': { 'server': 'SocketAddress',
'*export': 'str',
- '*tls-creds': 'str' } }
+ '*tls-creds': 'str',
+ '*reconnect-attempts': 'uint64',
+ '*reconnect-timeout': 'uint64' } }
##
# @BlockdevOptionsRaw:
diff --git a/block/nbd-client.h b/block/nbd-client.h
index f6c8052573..2561e1ea42 100644
--- a/block/nbd-client.h
+++ b/block/nbd-client.h
@@ -56,6 +56,8 @@ int nbd_client_init(BlockDriverState *bs,
const char *export_name,
QCryptoTLSCreds *tlscreds,
const char *hostname,
+ uint64_t reconnect_attempts,
+ uint64_t reconnect_timeout,
Error **errp);
void nbd_client_close(BlockDriverState *bs);
diff --git a/block/nbd-client.c b/block/nbd-client.c
index 44ac4ebc31..f22ed7f404 100644
--- a/block/nbd-client.c
+++ b/block/nbd-client.c
@@ -86,6 +86,8 @@ typedef struct NBDConnection {
const char *export;
QCryptoTLSCreds *tlscreds;
const char *hostname;
+ uint64_t reconnect_attempts;
+ uint64_t reconnect_timeout;
} NBDConnection;
static coroutine_fn void nbd_connection_entry(void *opaque)
@@ -96,6 +98,13 @@ static coroutine_fn void nbd_connection_entry(void *opaque)
int ret = 0;
Error *local_err = NULL;
+ if (con->reconnect_attempts != 0) {
+ error_setg(&s->connect_err, "Reconnect is not supported yet");
+ s->connect_status = -EINVAL;
+ nbd_channel_error(s, s->connect_status);
+ return;
+ }
+
s->connect_status = nbd_client_connect(con->bs, con->saddr,
con->export, con->tlscreds,
con->hostname, &s->connect_err);
@@ -1106,6 +1115,8 @@ int nbd_client_init(BlockDriverState *bs,
const char *export,
QCryptoTLSCreds *tlscreds,
const char *hostname,
+ uint64_t reconnect_attempts,
+ uint64_t reconnect_timeout,
Error **errp)
{
NBDClientSession *client = nbd_get_client_session(bs);
@@ -1116,6 +1127,8 @@ int nbd_client_init(BlockDriverState *bs,
con->export = export;
con->tlscreds = tlscreds;
con->hostname = hostname;
+ con->reconnect_attempts = reconnect_attempts;
+ con->reconnect_timeout = reconnect_timeout;
qemu_co_mutex_init(&client->send_mutex);
qemu_co_queue_init(&client->free_sema);
diff --git a/block/nbd.c b/block/nbd.c
index a851b8cd68..8c81d4a151 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -364,6 +364,20 @@ static QemuOptsList nbd_runtime_opts = {
.type = QEMU_OPT_STRING,
.help = "ID of the TLS credentials to use",
},
+ {
+ .name = "reconnect-attempts",
+ .type = QEMU_OPT_NUMBER,
+ .help = "Number of connection attempts on disconnect. "
+ "Must be >= 0. Default is 0. On nbd disk open, there would
"
+ "be maximum of @reconnect-attempts + 1 total tries to "
+ "connect",
+ },
+ {
+ .name = "reconnect-timeout",
+ .type = QEMU_OPT_NUMBER,
+ .help = "Timeout between reconnect attempts in nanoseconds. "
+ "Default is 1000000000 (one second)",
+ },
{ /* end of list */ }
},
};
@@ -376,6 +390,8 @@ static int nbd_open(BlockDriverState *bs, QDict *options,
int flags,
Error *local_err = NULL;
QCryptoTLSCreds *tlscreds = NULL;
const char *hostname = NULL;
+ uint64_t reconnect_attempts;
+ uint64_t reconnect_timeout;
int ret = -EINVAL;
opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort);
@@ -413,8 +429,12 @@ static int nbd_open(BlockDriverState *bs, QDict *options,
int flags,
hostname = s->saddr->u.inet.host;
}
+ reconnect_attempts = qemu_opt_get_number(opts, "reconnect-attempts", 0);
+ reconnect_timeout = qemu_opt_get_number(opts, "reconnect-timeout",
+ 1000000000L);
/* NBD handshake */
- ret = nbd_client_init(bs, s->saddr, s->export, tlscreds, hostname, errp);
+ ret = nbd_client_init(bs, s->saddr, s->export, tlscreds, hostname,
+ reconnect_attempts, reconnect_timeout, errp);
error:
if (tlscreds) {
--
2.11.1
