diff options
| -rw-r--r-- | block/monitor/block-hmp-cmds.c | 2 | ||||
| -rw-r--r-- | blockdev-nbd.c | 33 | ||||
| -rw-r--r-- | include/block/nbd.h | 3 | ||||
| -rw-r--r-- | qapi/block-export.json | 10 | ||||
| -rw-r--r-- | storage-daemon/qemu-storage-daemon.c | 4 |
5 files changed, 39 insertions, 13 deletions
diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c index fb632b1..662b7f7 100644 --- a/block/monitor/block-hmp-cmds.c +++ b/block/monitor/block-hmp-cmds.c @@ -411,7 +411,7 @@ void hmp_nbd_server_start(Monitor *mon, const QDict *qdict) goto exit; } - nbd_server_start(addr, NULL, NULL, &local_err); + nbd_server_start(addr, NULL, NULL, 0, &local_err); qapi_free_SocketAddress(addr); if (local_err != NULL) { goto exit; diff --git a/blockdev-nbd.c b/blockdev-nbd.c index 7bcca10..41d5542 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -23,23 +23,41 @@ typedef struct NBDServerData { QIONetListener *listener; QCryptoTLSCreds *tlscreds; char *tlsauthz; + uint32_t max_connections; + uint32_t connections; } NBDServerData; static NBDServerData *nbd_server; +static void nbd_update_server_watch(NBDServerData *s); + static void nbd_blockdev_client_closed(NBDClient *client, bool ignored) { nbd_client_put(client); + assert(nbd_server->connections > 0); + nbd_server->connections--; + nbd_update_server_watch(nbd_server); } static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, gpointer opaque) { + nbd_server->connections++; + nbd_update_server_watch(nbd_server); + qio_channel_set_name(QIO_CHANNEL(cioc), "nbd-server"); nbd_client_new(cioc, nbd_server->tlscreds, nbd_server->tlsauthz, nbd_blockdev_client_closed); } +static void nbd_update_server_watch(NBDServerData *s) +{ + if (!s->max_connections || s->connections < s->max_connections) { + qio_net_listener_set_client_func(s->listener, nbd_accept, NULL, NULL); + } else { + qio_net_listener_set_client_func(s->listener, NULL, NULL, NULL); + } +} static void nbd_server_free(NBDServerData *server) { @@ -88,7 +106,8 @@ static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) void nbd_server_start(SocketAddress *addr, const char *tls_creds, - const char *tls_authz, Error **errp) + const char *tls_authz, uint32_t max_connections, + Error **errp) { if (nbd_server) { error_setg(errp, "NBD server already running"); @@ -96,6 +115,7 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds, } nbd_server = g_new0(NBDServerData, 1); + nbd_server->max_connections = max_connections; nbd_server->listener = qio_net_listener_new(); qio_net_listener_set_name(nbd_server->listener, @@ -120,10 +140,7 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds, nbd_server->tlsauthz = g_strdup(tls_authz); - qio_net_listener_set_client_func(nbd_server->listener, - nbd_accept, - NULL, - NULL); + nbd_update_server_watch(nbd_server); return; @@ -134,17 +151,19 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds, void nbd_server_start_options(NbdServerOptions *arg, Error **errp) { - nbd_server_start(arg->addr, arg->tls_creds, arg->tls_authz, errp); + nbd_server_start(arg->addr, arg->tls_creds, arg->tls_authz, + arg->max_connections, errp); } void qmp_nbd_server_start(SocketAddressLegacy *addr, bool has_tls_creds, const char *tls_creds, bool has_tls_authz, const char *tls_authz, + bool has_max_connections, uint32_t max_connections, Error **errp) { SocketAddress *addr_flat = socket_address_flatten(addr); - nbd_server_start(addr_flat, tls_creds, tls_authz, errp); + nbd_server_start(addr_flat, tls_creds, tls_authz, max_connections, errp); qapi_free_SocketAddress(addr_flat); } diff --git a/include/block/nbd.h b/include/block/nbd.h index f55f5b7..acccdb3 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -354,7 +354,8 @@ void nbd_client_get(NBDClient *client); void nbd_client_put(NBDClient *client); void nbd_server_start(SocketAddress *addr, const char *tls_creds, - const char *tls_authz, Error **errp); + const char *tls_authz, uint32_t max_connections, + Error **errp); void nbd_server_start_options(NbdServerOptions *arg, Error **errp); /* nbd_read diff --git a/qapi/block-export.json b/qapi/block-export.json index 5890a94..8aa8a01 100644 --- a/qapi/block-export.json +++ b/qapi/block-export.json @@ -20,13 +20,16 @@ # is only resolved at time of use, so can be deleted and # recreated on the fly while the NBD server is active. # If missing, it will default to denying access (since 4.0). +# @max-connections: The maximum number of connections to allow at the same +# time, 0 for unlimited. (since 5.2; default: 0) # # Since: 4.2 ## { 'struct': 'NbdServerOptions', 'data': { 'addr': 'SocketAddress', '*tls-creds': 'str', - '*tls-authz': 'str'} } + '*tls-authz': 'str', + '*max-connections': 'uint32' } } ## # @nbd-server-start: @@ -46,6 +49,8 @@ # is only resolved at time of use, so can be deleted and # recreated on the fly while the NBD server is active. # If missing, it will default to denying access (since 4.0). +# @max-connections: The maximum number of connections to allow at the same +# time, 0 for unlimited. (since 5.2; default: 0) # # Returns: error if the server is already running. # @@ -54,7 +59,8 @@ { 'command': 'nbd-server-start', 'data': { 'addr': 'SocketAddressLegacy', '*tls-creds': 'str', - '*tls-authz': 'str'} } + '*tls-authz': 'str', + '*max-connections': 'uint32' } } ## # @BlockExportOptionsNbd: diff --git a/storage-daemon/qemu-storage-daemon.c b/storage-daemon/qemu-storage-daemon.c index b6f678d..0fcab6e 100644 --- a/storage-daemon/qemu-storage-daemon.c +++ b/storage-daemon/qemu-storage-daemon.c @@ -101,9 +101,9 @@ static void help(void) " configure a QMP monitor\n" "\n" " --nbd-server addr.type=inet,addr.host=<host>,addr.port=<port>\n" -" [,tls-creds=<id>][,tls-authz=<id>]\n" +" [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n" " --nbd-server addr.type=unix,addr.path=<path>\n" -" [,tls-creds=<id>][,tls-authz=<id>]\n" +" [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n" " start an NBD server for exporting block nodes\n" "\n" " --object help list object types that can be added\n" |