Disabling execution of cyclictest as part of verify job.
[kvmfornfv.git] / qemu / blockdev-nbd.c
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  */
11
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"
19 #include "trace.h"
20 #include "block/nbd.h"
21 #include "io/channel-socket.h"
22
23 typedef struct NBDServerData {
24     QIOChannelSocket *listen_ioc;
25     int watch;
26     QCryptoTLSCreds *tlscreds;
27 } NBDServerData;
28
29 static NBDServerData *nbd_server;
30
31
32 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition condition,
33                            gpointer opaque)
34 {
35     QIOChannelSocket *cioc;
36
37     if (!nbd_server) {
38         return FALSE;
39     }
40
41     cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc),
42                                      NULL);
43     if (!cioc) {
44         return TRUE;
45     }
46
47     nbd_client_new(NULL, cioc,
48                    nbd_server->tlscreds, NULL,
49                    nbd_client_put);
50     object_unref(OBJECT(cioc));
51     return TRUE;
52 }
53
54
55 static void nbd_server_free(NBDServerData *server)
56 {
57     if (!server) {
58         return;
59     }
60
61     if (server->watch != -1) {
62         g_source_remove(server->watch);
63     }
64     object_unref(OBJECT(server->listen_ioc));
65     if (server->tlscreds) {
66         object_unref(OBJECT(server->tlscreds));
67     }
68
69     g_free(server);
70 }
71
72 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
73 {
74     Object *obj;
75     QCryptoTLSCreds *creds;
76
77     obj = object_resolve_path_component(
78         object_get_objects_root(), id);
79     if (!obj) {
80         error_setg(errp, "No TLS credentials with id '%s'",
81                    id);
82         return NULL;
83     }
84     creds = (QCryptoTLSCreds *)
85         object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
86     if (!creds) {
87         error_setg(errp, "Object with id '%s' is not TLS credentials",
88                    id);
89         return NULL;
90     }
91
92     if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
93         error_setg(errp,
94                    "Expecting TLS credentials with a server endpoint");
95         return NULL;
96     }
97     object_ref(obj);
98     return creds;
99 }
100
101
102 void qmp_nbd_server_start(SocketAddress *addr,
103                           bool has_tls_creds, const char *tls_creds,
104                           Error **errp)
105 {
106     if (nbd_server) {
107         error_setg(errp, "NBD server already running");
108         return;
109     }
110
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) {
116         goto error;
117     }
118
119     if (has_tls_creds) {
120         nbd_server->tlscreds = nbd_get_tls_creds(tls_creds, errp);
121         if (!nbd_server->tlscreds) {
122             goto error;
123         }
124
125         if (addr->type != SOCKET_ADDRESS_KIND_INET) {
126             error_setg(errp, "TLS is only supported with IPv4/IPv6");
127             goto error;
128         }
129     }
130
131     nbd_server->watch = qio_channel_add_watch(
132         QIO_CHANNEL(nbd_server->listen_ioc),
133         G_IO_IN,
134         nbd_accept,
135         NULL,
136         NULL);
137
138     return;
139
140  error:
141     nbd_server_free(nbd_server);
142     nbd_server = NULL;
143 }
144
145 void qmp_nbd_server_add(const char *device, bool has_writable, bool writable,
146                         Error **errp)
147 {
148     BlockBackend *blk;
149     NBDExport *exp;
150
151     if (!nbd_server) {
152         error_setg(errp, "NBD server not running");
153         return;
154     }
155
156     if (nbd_export_find(device)) {
157         error_setg(errp, "NBD server already exporting device '%s'", device);
158         return;
159     }
160
161     blk = blk_by_name(device);
162     if (!blk) {
163         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
164                   "Device '%s' not found", device);
165         return;
166     }
167     if (!blk_is_inserted(blk)) {
168         error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
169         return;
170     }
171
172     if (!has_writable) {
173         writable = false;
174     }
175     if (blk_is_read_only(blk)) {
176         writable = false;
177     }
178
179     exp = nbd_export_new(blk, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY, NULL,
180                          errp);
181     if (!exp) {
182         return;
183     }
184
185     nbd_export_set_name(exp, device);
186
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. */
190     nbd_export_put(exp);
191 }
192
193 void qmp_nbd_server_stop(Error **errp)
194 {
195     nbd_export_close_all();
196
197     nbd_server_free(nbd_server);
198     nbd_server = NULL;
199 }