2 * Serving QEMU block devices via NBD
4 * Copyright (c) 2012 Red Hat, Inc.
6 * Author: Paolo Bonzini <pbonzini@redhat.com>
8 * This work is licensed under the terms of the GNU GPL, version 2 or
9 * later. See the COPYING file in the top-level directory.
12 #include "qemu/osdep.h"
13 #include "sysemu/blockdev.h"
14 #include "sysemu/block-backend.h"
15 #include "hw/block/block.h"
16 #include "qapi/qmp/qerror.h"
17 #include "sysemu/sysemu.h"
18 #include "qmp-commands.h"
20 #include "block/nbd.h"
21 #include "io/channel-socket.h"
23 typedef struct NBDServerData {
24 QIOChannelSocket *listen_ioc;
26 QCryptoTLSCreds *tlscreds;
29 static NBDServerData *nbd_server;
32 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition condition,
35 QIOChannelSocket *cioc;
41 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc),
47 nbd_client_new(NULL, cioc,
48 nbd_server->tlscreds, NULL,
50 object_unref(OBJECT(cioc));
55 static void nbd_server_free(NBDServerData *server)
61 if (server->watch != -1) {
62 g_source_remove(server->watch);
64 object_unref(OBJECT(server->listen_ioc));
65 if (server->tlscreds) {
66 object_unref(OBJECT(server->tlscreds));
72 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
75 QCryptoTLSCreds *creds;
77 obj = object_resolve_path_component(
78 object_get_objects_root(), id);
80 error_setg(errp, "No TLS credentials with id '%s'",
84 creds = (QCryptoTLSCreds *)
85 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
87 error_setg(errp, "Object with id '%s' is not TLS credentials",
92 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
94 "Expecting TLS credentials with a server endpoint");
102 void qmp_nbd_server_start(SocketAddress *addr,
103 bool has_tls_creds, const char *tls_creds,
107 error_setg(errp, "NBD server already running");
111 nbd_server = g_new0(NBDServerData, 1);
112 nbd_server->watch = -1;
113 nbd_server->listen_ioc = qio_channel_socket_new();
114 if (qio_channel_socket_listen_sync(
115 nbd_server->listen_ioc, addr, errp) < 0) {
120 nbd_server->tlscreds = nbd_get_tls_creds(tls_creds, errp);
121 if (!nbd_server->tlscreds) {
125 if (addr->type != SOCKET_ADDRESS_KIND_INET) {
126 error_setg(errp, "TLS is only supported with IPv4/IPv6");
131 nbd_server->watch = qio_channel_add_watch(
132 QIO_CHANNEL(nbd_server->listen_ioc),
141 nbd_server_free(nbd_server);
145 void qmp_nbd_server_add(const char *device, bool has_writable, bool writable,
152 error_setg(errp, "NBD server not running");
156 if (nbd_export_find(device)) {
157 error_setg(errp, "NBD server already exporting device '%s'", device);
161 blk = blk_by_name(device);
163 error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
164 "Device '%s' not found", device);
167 if (!blk_is_inserted(blk)) {
168 error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
175 if (blk_is_read_only(blk)) {
179 exp = nbd_export_new(blk, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY, NULL,
185 nbd_export_set_name(exp, device);
187 /* The list of named exports has a strong reference to this export now and
188 * our only way of accessing it is through nbd_export_find(), so we can drop
189 * the strong reference that is @exp. */
193 void qmp_nbd_server_stop(Error **errp)
195 nbd_export_close_all();
197 nbd_server_free(nbd_server);