From 130d49baa50655729f09efb72e77bebf09421dd7 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Thu, 10 Jun 2021 13:07:49 +0300 Subject: [PATCH] nbd/client-connection: add possibility of negotiation Add arguments and logic to support nbd negotiation in the same thread after successful connection. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20210610100802.5888-20-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake Signed-off-by: Eric Blake --- block/nbd.c | 4 +- include/block/nbd.h | 9 +++- nbd/client-connection.c | 105 ++++++++++++++++++++++++++++++++++++++-- 3 files changed, 109 insertions(+), 9 deletions(-) diff --git a/block/nbd.c b/block/nbd.c index 26914509f1..df9d241313 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -357,7 +357,7 @@ static coroutine_fn void nbd_reconnect_attempt(BDRVNBDState *s) s->ioc = NULL; } - s->sioc = nbd_co_establish_connection(s->conn, NULL); + s->sioc = nbd_co_establish_connection(s->conn, NULL, NULL, NULL); if (!s->sioc) { ret = -ECONNREFUSED; goto out; @@ -2035,7 +2035,7 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } - s->conn = nbd_client_connection_new(s->saddr); + s->conn = nbd_client_connection_new(s->saddr, false, NULL, NULL, NULL); /* * establish TCP connection, return error if it fails diff --git a/include/block/nbd.h b/include/block/nbd.h index 57381be76f..5d86e6a393 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -409,11 +409,16 @@ const char *nbd_err_lookup(int err); /* nbd/client-connection.c */ typedef struct NBDClientConnection NBDClientConnection; -NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr); +NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr, + bool do_negotiation, + const char *export_name, + const char *x_dirty_bitmap, + QCryptoTLSCreds *tlscreds); void nbd_client_connection_release(NBDClientConnection *conn); QIOChannelSocket *coroutine_fn -nbd_co_establish_connection(NBDClientConnection *conn, Error **errp); +nbd_co_establish_connection(NBDClientConnection *conn, NBDExportInfo *info, + QIOChannel **ioc, Error **errp); void coroutine_fn nbd_co_establish_connection_cancel(NBDClientConnection *conn); diff --git a/nbd/client-connection.c b/nbd/client-connection.c index eb5cae2eae..4ed37cd73f 100644 --- a/nbd/client-connection.c +++ b/nbd/client-connection.c @@ -30,8 +30,11 @@ #include "qapi/clone-visitor.h" struct NBDClientConnection { - /* Initialization constants */ + /* Initialization constants, never change */ SocketAddress *saddr; /* address to connect to */ + QCryptoTLSCreds *tlscreds; + NBDExportInfo initial_info; + bool do_negotiation; QemuMutex mutex; @@ -42,7 +45,9 @@ struct NBDClientConnection { * nbd_co_establish_connection then steals these pointers while * under the mutex. */ + NBDExportInfo updated_info; QIOChannelSocket *sioc; + QIOChannel *ioc; Error *err; /* All further fields are accessed only under mutex */ @@ -56,12 +61,25 @@ struct NBDClientConnection { Coroutine *wait_co; }; -NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr) +NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr, + bool do_negotiation, + const char *export_name, + const char *x_dirty_bitmap, + QCryptoTLSCreds *tlscreds) { NBDClientConnection *conn = g_new(NBDClientConnection, 1); + object_ref(OBJECT(tlscreds)); *conn = (NBDClientConnection) { .saddr = QAPI_CLONE(SocketAddress, saddr), + .tlscreds = tlscreds, + .do_negotiation = do_negotiation, + + .initial_info.request_sizes = true, + .initial_info.structured_reply = true, + .initial_info.base_allocation = true, + .initial_info.x_dirty_bitmap = g_strdup(x_dirty_bitmap), + .initial_info.name = g_strdup(export_name ?: "") }; qemu_mutex_init(&conn->mutex); @@ -77,9 +95,61 @@ static void nbd_client_connection_do_free(NBDClientConnection *conn) } error_free(conn->err); qapi_free_SocketAddress(conn->saddr); + object_unref(OBJECT(conn->tlscreds)); + g_free(conn->initial_info.x_dirty_bitmap); + g_free(conn->initial_info.name); g_free(conn); } +/* + * Connect to @addr and do NBD negotiation if @info is not null. If @tlscreds + * are given @outioc is returned. @outioc is provided only on success. The call + * may be cancelled from other thread by simply qio_channel_shutdown(sioc). + */ +static int nbd_connect(QIOChannelSocket *sioc, SocketAddress *addr, + NBDExportInfo *info, QCryptoTLSCreds *tlscreds, + QIOChannel **outioc, Error **errp) +{ + int ret; + + if (outioc) { + *outioc = NULL; + } + + ret = qio_channel_socket_connect_sync(sioc, addr, errp); + if (ret < 0) { + return ret; + } + + qio_channel_set_delay(QIO_CHANNEL(sioc), false); + + if (!info) { + return 0; + } + + ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), tlscreds, + tlscreds ? addr->u.inet.host : NULL, + outioc, info, errp); + if (ret < 0) { + /* + * nbd_receive_negotiate() may setup tls ioc and return it even on + * failure path. In this case we should use it instead of original + * channel. + */ + if (outioc && *outioc) { + qio_channel_close(QIO_CHANNEL(*outioc), NULL); + object_unref(OBJECT(*outioc)); + *outioc = NULL; + } else { + qio_channel_close(QIO_CHANNEL(sioc), NULL); + } + + return ret; + } + + return 0; +} + static void *connect_thread_func(void *opaque) { NBDClientConnection *conn = opaque; @@ -90,13 +160,18 @@ static void *connect_thread_func(void *opaque) error_free(conn->err); conn->err = NULL; - ret = qio_channel_socket_connect_sync(conn->sioc, conn->saddr, &conn->err); + conn->updated_info = conn->initial_info; + + ret = nbd_connect(conn->sioc, conn->saddr, + conn->do_negotiation ? &conn->updated_info : NULL, + conn->tlscreds, &conn->ioc, &conn->err); if (ret < 0) { object_unref(OBJECT(conn->sioc)); conn->sioc = NULL; } - qio_channel_set_delay(QIO_CHANNEL(conn->sioc), false); + conn->updated_info.x_dirty_bitmap = NULL; + conn->updated_info.name = NULL; qemu_mutex_lock(&conn->mutex); @@ -146,12 +221,24 @@ void nbd_client_connection_release(NBDClientConnection *conn) * result, just return it now * otherwise the thread is not running, so start a thread and wait for * completion + * + * If @info is not NULL, also do nbd-negotiation after successful connection. + * In this case info is used only as out parameter, and is fully initialized by + * nbd_co_establish_connection(). "IN" fields of info as well as related only to + * nbd_receive_export_list() would be zero (see description of NBDExportInfo in + * include/block/nbd.h). */ QIOChannelSocket *coroutine_fn -nbd_co_establish_connection(NBDClientConnection *conn, Error **errp) +nbd_co_establish_connection(NBDClientConnection *conn, NBDExportInfo *info, + QIOChannel **ioc, Error **errp) { QemuThread thread; + if (conn->do_negotiation) { + assert(info); + assert(ioc); + } + WITH_QEMU_LOCK_GUARD(&conn->mutex) { /* * Don't call nbd_co_establish_connection() in several coroutines in @@ -162,6 +249,10 @@ nbd_co_establish_connection(NBDClientConnection *conn, Error **errp) if (!conn->running) { if (conn->sioc) { /* Previous attempt finally succeeded in background */ + if (conn->do_negotiation) { + *ioc = g_steal_pointer(&conn->ioc); + memcpy(info, &conn->updated_info, sizeof(*info)); + } return g_steal_pointer(&conn->sioc); } @@ -194,6 +285,10 @@ nbd_co_establish_connection(NBDClientConnection *conn, Error **errp) } else { error_propagate(errp, conn->err); conn->err = NULL; + if (conn->sioc && conn->do_negotiation) { + *ioc = g_steal_pointer(&conn->ioc); + memcpy(info, &conn->updated_info, sizeof(*info)); + } return g_steal_pointer(&conn->sioc); } }