Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20190719' into staging
[qemu/ar7.git] / blockdev-nbd.c
blob66eebab31875dfab1d18a898ca9b18a186c10f91
1 /*
2  * Serving QEMU block devices via NBD
3  *
4  * Copyright (c) 2012 Red Hat, Inc.
5  *
6  * Author: Paolo Bonzini <pbonzini@redhat.com>
7  *
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.
10  */
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/error.h"
17 #include "qapi/qapi-commands-block.h"
18 #include "sysemu/sysemu.h"
19 #include "block/nbd.h"
20 #include "io/channel-socket.h"
21 #include "io/net-listener.h"
23 typedef struct NBDServerData {
24     QIONetListener *listener;
25     QCryptoTLSCreds *tlscreds;
26     char *tlsauthz;
27 } NBDServerData;
29 static NBDServerData *nbd_server;
31 static void nbd_blockdev_client_closed(NBDClient *client, bool ignored)
33     nbd_client_put(client);
36 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
37                        gpointer opaque)
39     qio_channel_set_name(QIO_CHANNEL(cioc), "nbd-server");
40     nbd_client_new(cioc, nbd_server->tlscreds, nbd_server->tlsauthz,
41                    nbd_blockdev_client_closed);
45 static void nbd_server_free(NBDServerData *server)
47     if (!server) {
48         return;
49     }
51     qio_net_listener_disconnect(server->listener);
52     object_unref(OBJECT(server->listener));
53     if (server->tlscreds) {
54         object_unref(OBJECT(server->tlscreds));
55     }
56     g_free(server->tlsauthz);
58     g_free(server);
61 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
63     Object *obj;
64     QCryptoTLSCreds *creds;
66     obj = object_resolve_path_component(
67         object_get_objects_root(), id);
68     if (!obj) {
69         error_setg(errp, "No TLS credentials with id '%s'",
70                    id);
71         return NULL;
72     }
73     creds = (QCryptoTLSCreds *)
74         object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
75     if (!creds) {
76         error_setg(errp, "Object with id '%s' is not TLS credentials",
77                    id);
78         return NULL;
79     }
81     if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
82         error_setg(errp,
83                    "Expecting TLS credentials with a server endpoint");
84         return NULL;
85     }
86     object_ref(obj);
87     return creds;
91 void nbd_server_start(SocketAddress *addr, const char *tls_creds,
92                       const char *tls_authz, Error **errp)
94     if (nbd_server) {
95         error_setg(errp, "NBD server already running");
96         return;
97     }
99     nbd_server = g_new0(NBDServerData, 1);
100     nbd_server->listener = qio_net_listener_new();
102     qio_net_listener_set_name(nbd_server->listener,
103                               "nbd-listener");
105     if (qio_net_listener_open_sync(nbd_server->listener, addr, errp) < 0) {
106         goto error;
107     }
109     if (tls_creds) {
110         nbd_server->tlscreds = nbd_get_tls_creds(tls_creds, errp);
111         if (!nbd_server->tlscreds) {
112             goto error;
113         }
115         /* TODO SOCKET_ADDRESS_TYPE_FD where fd has AF_INET or AF_INET6 */
116         if (addr->type != SOCKET_ADDRESS_TYPE_INET) {
117             error_setg(errp, "TLS is only supported with IPv4/IPv6");
118             goto error;
119         }
120     }
122     nbd_server->tlsauthz = g_strdup(tls_authz);
124     qio_net_listener_set_client_func(nbd_server->listener,
125                                      nbd_accept,
126                                      NULL,
127                                      NULL);
129     return;
131  error:
132     nbd_server_free(nbd_server);
133     nbd_server = NULL;
136 void qmp_nbd_server_start(SocketAddressLegacy *addr,
137                           bool has_tls_creds, const char *tls_creds,
138                           bool has_tls_authz, const char *tls_authz,
139                           Error **errp)
141     SocketAddress *addr_flat = socket_address_flatten(addr);
143     nbd_server_start(addr_flat, tls_creds, tls_authz, errp);
144     qapi_free_SocketAddress(addr_flat);
147 void qmp_nbd_server_add(const char *device, bool has_name, const char *name,
148                         bool has_writable, bool writable,
149                         bool has_bitmap, const char *bitmap, Error **errp)
151     BlockDriverState *bs = NULL;
152     BlockBackend *on_eject_blk;
153     NBDExport *exp;
154     int64_t len;
156     if (!nbd_server) {
157         error_setg(errp, "NBD server not running");
158         return;
159     }
161     if (!has_name) {
162         name = device;
163     }
165     if (nbd_export_find(name)) {
166         error_setg(errp, "NBD server already has export named '%s'", name);
167         return;
168     }
170     on_eject_blk = blk_by_name(device);
172     bs = bdrv_lookup_bs(device, device, errp);
173     if (!bs) {
174         return;
175     }
177     len = bdrv_getlength(bs);
178     if (len < 0) {
179         error_setg_errno(errp, -len,
180                          "Failed to determine the NBD export's length");
181         return;
182     }
184     if (!has_writable) {
185         writable = false;
186     }
187     if (bdrv_is_read_only(bs)) {
188         writable = false;
189     }
191     exp = nbd_export_new(bs, 0, len, name, NULL, bitmap,
192                          writable ? 0 : NBD_FLAG_READ_ONLY,
193                          NULL, false, on_eject_blk, errp);
194     if (!exp) {
195         return;
196     }
198     /* The list of named exports has a strong reference to this export now and
199      * our only way of accessing it is through nbd_export_find(), so we can drop
200      * the strong reference that is @exp. */
201     nbd_export_put(exp);
204 void qmp_nbd_server_remove(const char *name,
205                            bool has_mode, NbdServerRemoveMode mode,
206                            Error **errp)
208     NBDExport *exp;
210     if (!nbd_server) {
211         error_setg(errp, "NBD server not running");
212         return;
213     }
215     exp = nbd_export_find(name);
216     if (exp == NULL) {
217         error_setg(errp, "Export '%s' is not found", name);
218         return;
219     }
221     if (!has_mode) {
222         mode = NBD_SERVER_REMOVE_MODE_SAFE;
223     }
225     nbd_export_remove(exp, mode, errp);
228 void qmp_nbd_server_stop(Error **errp)
230     if (!nbd_server) {
231         error_setg(errp, "NBD server not running");
232         return;
233     }
235     nbd_export_close_all();
237     nbd_server_free(nbd_server);
238     nbd_server = NULL;