nbd/client: Add x-dirty-bitmap to query bitmap from server
[qemu.git] / block / nbd.c
1 /*
2 * QEMU Block driver for NBD
3 *
4 * Copyright (C) 2008 Bull S.A.S.
5 * Author: Laurent Vivier <Laurent.Vivier@bull.net>
6 *
7 * Some parts:
8 * Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws>
9 *
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
16 *
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26 * THE SOFTWARE.
27 */
28
29 #include "qemu/osdep.h"
30 #include "nbd-client.h"
31 #include "block/qdict.h"
32 #include "qapi/error.h"
33 #include "qemu/uri.h"
34 #include "block/block_int.h"
35 #include "qemu/module.h"
36 #include "qemu/option.h"
37 #include "qapi/qapi-visit-sockets.h"
38 #include "qapi/qobject-input-visitor.h"
39 #include "qapi/qobject-output-visitor.h"
40 #include "qapi/qmp/qdict.h"
41 #include "qapi/qmp/qstring.h"
42 #include "qemu/cutils.h"
43
44 #define EN_OPTSTR ":exportname="
45
46 typedef struct BDRVNBDState {
47 NBDClientSession client;
48
49 /* For nbd_refresh_filename() */
50 SocketAddress *saddr;
51 char *export, *tlscredsid;
52 } BDRVNBDState;
53
54 static int nbd_parse_uri(const char *filename, QDict *options)
55 {
56 URI *uri;
57 const char *p;
58 QueryParams *qp = NULL;
59 int ret = 0;
60 bool is_unix;
61
62 uri = uri_parse(filename);
63 if (!uri) {
64 return -EINVAL;
65 }
66
67 /* transport */
68 if (!g_strcmp0(uri->scheme, "nbd")) {
69 is_unix = false;
70 } else if (!g_strcmp0(uri->scheme, "nbd+tcp")) {
71 is_unix = false;
72 } else if (!g_strcmp0(uri->scheme, "nbd+unix")) {
73 is_unix = true;
74 } else {
75 ret = -EINVAL;
76 goto out;
77 }
78
79 p = uri->path ? uri->path : "/";
80 p += strspn(p, "/");
81 if (p[0]) {
82 qdict_put_str(options, "export", p);
83 }
84
85 qp = query_params_parse(uri->query);
86 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) {
87 ret = -EINVAL;
88 goto out;
89 }
90
91 if (is_unix) {
92 /* nbd+unix:///export?socket=path */
93 if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) {
94 ret = -EINVAL;
95 goto out;
96 }
97 qdict_put_str(options, "server.type", "unix");
98 qdict_put_str(options, "server.path", qp->p[0].value);
99 } else {
100 QString *host;
101 char *port_str;
102
103 /* nbd[+tcp]://host[:port]/export */
104 if (!uri->server) {
105 ret = -EINVAL;
106 goto out;
107 }
108
109 /* strip braces from literal IPv6 address */
110 if (uri->server[0] == '[') {
111 host = qstring_from_substr(uri->server, 1,
112 strlen(uri->server) - 2);
113 } else {
114 host = qstring_from_str(uri->server);
115 }
116
117 qdict_put_str(options, "server.type", "inet");
118 qdict_put(options, "server.host", host);
119
120 port_str = g_strdup_printf("%d", uri->port ?: NBD_DEFAULT_PORT);
121 qdict_put_str(options, "server.port", port_str);
122 g_free(port_str);
123 }
124
125 out:
126 if (qp) {
127 query_params_free(qp);
128 }
129 uri_free(uri);
130 return ret;
131 }
132
133 static bool nbd_has_filename_options_conflict(QDict *options, Error **errp)
134 {
135 const QDictEntry *e;
136
137 for (e = qdict_first(options); e; e = qdict_next(options, e)) {
138 if (!strcmp(e->key, "host") ||
139 !strcmp(e->key, "port") ||
140 !strcmp(e->key, "path") ||
141 !strcmp(e->key, "export") ||
142 strstart(e->key, "server.", NULL))
143 {
144 error_setg(errp, "Option '%s' cannot be used with a file name",
145 e->key);
146 return true;
147 }
148 }
149
150 return false;
151 }
152
153 static void nbd_parse_filename(const char *filename, QDict *options,
154 Error **errp)
155 {
156 char *file;
157 char *export_name;
158 const char *host_spec;
159 const char *unixpath;
160
161 if (nbd_has_filename_options_conflict(options, errp)) {
162 return;
163 }
164
165 if (strstr(filename, "://")) {
166 int ret = nbd_parse_uri(filename, options);
167 if (ret < 0) {
168 error_setg(errp, "No valid URL specified");
169 }
170 return;
171 }
172
173 file = g_strdup(filename);
174
175 export_name = strstr(file, EN_OPTSTR);
176 if (export_name) {
177 if (export_name[strlen(EN_OPTSTR)] == 0) {
178 goto out;
179 }
180 export_name[0] = 0; /* truncate 'file' */
181 export_name += strlen(EN_OPTSTR);
182
183 qdict_put_str(options, "export", export_name);
184 }
185
186 /* extract the host_spec - fail if it's not nbd:... */
187 if (!strstart(file, "nbd:", &host_spec)) {
188 error_setg(errp, "File name string for NBD must start with 'nbd:'");
189 goto out;
190 }
191
192 if (!*host_spec) {
193 goto out;
194 }
195
196 /* are we a UNIX or TCP socket? */
197 if (strstart(host_spec, "unix:", &unixpath)) {
198 qdict_put_str(options, "server.type", "unix");
199 qdict_put_str(options, "server.path", unixpath);
200 } else {
201 InetSocketAddress *addr = g_new(InetSocketAddress, 1);
202
203 if (inet_parse(addr, host_spec, errp)) {
204 goto out_inet;
205 }
206
207 qdict_put_str(options, "server.type", "inet");
208 qdict_put_str(options, "server.host", addr->host);
209 qdict_put_str(options, "server.port", addr->port);
210 out_inet:
211 qapi_free_InetSocketAddress(addr);
212 }
213
214 out:
215 g_free(file);
216 }
217
218 static bool nbd_process_legacy_socket_options(QDict *output_options,
219 QemuOpts *legacy_opts,
220 Error **errp)
221 {
222 const char *path = qemu_opt_get(legacy_opts, "path");
223 const char *host = qemu_opt_get(legacy_opts, "host");
224 const char *port = qemu_opt_get(legacy_opts, "port");
225 const QDictEntry *e;
226
227 if (!path && !host && !port) {
228 return true;
229 }
230
231 for (e = qdict_first(output_options); e; e = qdict_next(output_options, e))
232 {
233 if (strstart(e->key, "server.", NULL)) {
234 error_setg(errp, "Cannot use 'server' and path/host/port at the "
235 "same time");
236 return false;
237 }
238 }
239
240 if (path && host) {
241 error_setg(errp, "path and host may not be used at the same time");
242 return false;
243 } else if (path) {
244 if (port) {
245 error_setg(errp, "port may not be used without host");
246 return false;
247 }
248
249 qdict_put_str(output_options, "server.type", "unix");
250 qdict_put_str(output_options, "server.path", path);
251 } else if (host) {
252 qdict_put_str(output_options, "server.type", "inet");
253 qdict_put_str(output_options, "server.host", host);
254 qdict_put_str(output_options, "server.port",
255 port ?: stringify(NBD_DEFAULT_PORT));
256 }
257
258 return true;
259 }
260
261 static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options,
262 Error **errp)
263 {
264 SocketAddress *saddr = NULL;
265 QDict *addr = NULL;
266 Visitor *iv = NULL;
267 Error *local_err = NULL;
268
269 qdict_extract_subqdict(options, &addr, "server.");
270 if (!qdict_size(addr)) {
271 error_setg(errp, "NBD server address missing");
272 goto done;
273 }
274
275 iv = qobject_input_visitor_new_flat_confused(addr, errp);
276 if (!iv) {
277 goto done;
278 }
279
280 visit_type_SocketAddress(iv, NULL, &saddr, &local_err);
281 if (local_err) {
282 error_propagate(errp, local_err);
283 goto done;
284 }
285
286 done:
287 qobject_unref(addr);
288 visit_free(iv);
289 return saddr;
290 }
291
292 NBDClientSession *nbd_get_client_session(BlockDriverState *bs)
293 {
294 BDRVNBDState *s = bs->opaque;
295 return &s->client;
296 }
297
298 static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr,
299 Error **errp)
300 {
301 QIOChannelSocket *sioc;
302 Error *local_err = NULL;
303
304 sioc = qio_channel_socket_new();
305 qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client");
306
307 qio_channel_socket_connect_sync(sioc,
308 saddr,
309 &local_err);
310 if (local_err) {
311 object_unref(OBJECT(sioc));
312 error_propagate(errp, local_err);
313 return NULL;
314 }
315
316 qio_channel_set_delay(QIO_CHANNEL(sioc), false);
317
318 return sioc;
319 }
320
321
322 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
323 {
324 Object *obj;
325 QCryptoTLSCreds *creds;
326
327 obj = object_resolve_path_component(
328 object_get_objects_root(), id);
329 if (!obj) {
330 error_setg(errp, "No TLS credentials with id '%s'",
331 id);
332 return NULL;
333 }
334 creds = (QCryptoTLSCreds *)
335 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
336 if (!creds) {
337 error_setg(errp, "Object with id '%s' is not TLS credentials",
338 id);
339 return NULL;
340 }
341
342 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
343 error_setg(errp,
344 "Expecting TLS credentials with a client endpoint");
345 return NULL;
346 }
347 object_ref(obj);
348 return creds;
349 }
350
351
352 static QemuOptsList nbd_runtime_opts = {
353 .name = "nbd",
354 .head = QTAILQ_HEAD_INITIALIZER(nbd_runtime_opts.head),
355 .desc = {
356 {
357 .name = "host",
358 .type = QEMU_OPT_STRING,
359 .help = "TCP host to connect to",
360 },
361 {
362 .name = "port",
363 .type = QEMU_OPT_STRING,
364 .help = "TCP port to connect to",
365 },
366 {
367 .name = "path",
368 .type = QEMU_OPT_STRING,
369 .help = "Unix socket path to connect to",
370 },
371 {
372 .name = "export",
373 .type = QEMU_OPT_STRING,
374 .help = "Name of the NBD export to open",
375 },
376 {
377 .name = "tls-creds",
378 .type = QEMU_OPT_STRING,
379 .help = "ID of the TLS credentials to use",
380 },
381 {
382 .name = "x-dirty-bitmap",
383 .type = QEMU_OPT_STRING,
384 .help = "experimental: expose named dirty bitmap in place of "
385 "block status",
386 },
387 { /* end of list */ }
388 },
389 };
390
391 static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
392 Error **errp)
393 {
394 BDRVNBDState *s = bs->opaque;
395 QemuOpts *opts = NULL;
396 Error *local_err = NULL;
397 QIOChannelSocket *sioc = NULL;
398 QCryptoTLSCreds *tlscreds = NULL;
399 const char *hostname = NULL;
400 int ret = -EINVAL;
401
402 opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort);
403 qemu_opts_absorb_qdict(opts, options, &local_err);
404 if (local_err) {
405 error_propagate(errp, local_err);
406 goto error;
407 }
408
409 /* Translate @host, @port, and @path to a SocketAddress */
410 if (!nbd_process_legacy_socket_options(options, opts, errp)) {
411 goto error;
412 }
413
414 /* Pop the config into our state object. Exit if invalid. */
415 s->saddr = nbd_config(s, options, errp);
416 if (!s->saddr) {
417 goto error;
418 }
419
420 s->export = g_strdup(qemu_opt_get(opts, "export"));
421
422 s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds"));
423 if (s->tlscredsid) {
424 tlscreds = nbd_get_tls_creds(s->tlscredsid, errp);
425 if (!tlscreds) {
426 goto error;
427 }
428
429 /* TODO SOCKET_ADDRESS_KIND_FD where fd has AF_INET or AF_INET6 */
430 if (s->saddr->type != SOCKET_ADDRESS_TYPE_INET) {
431 error_setg(errp, "TLS only supported over IP sockets");
432 goto error;
433 }
434 hostname = s->saddr->u.inet.host;
435 }
436
437 /* establish TCP connection, return error if it fails
438 * TODO: Configurable retry-until-timeout behaviour.
439 */
440 sioc = nbd_establish_connection(s->saddr, errp);
441 if (!sioc) {
442 ret = -ECONNREFUSED;
443 goto error;
444 }
445
446 /* NBD handshake */
447 ret = nbd_client_init(bs, sioc, s->export, tlscreds, hostname,
448 qemu_opt_get(opts, "x-dirty-bitmap"), errp);
449 error:
450 if (sioc) {
451 object_unref(OBJECT(sioc));
452 }
453 if (tlscreds) {
454 object_unref(OBJECT(tlscreds));
455 }
456 if (ret < 0) {
457 qapi_free_SocketAddress(s->saddr);
458 g_free(s->export);
459 g_free(s->tlscredsid);
460 }
461 qemu_opts_del(opts);
462 return ret;
463 }
464
465 static int nbd_co_flush(BlockDriverState *bs)
466 {
467 return nbd_client_co_flush(bs);
468 }
469
470 static void nbd_refresh_limits(BlockDriverState *bs, Error **errp)
471 {
472 NBDClientSession *s = nbd_get_client_session(bs);
473 uint32_t min = s->info.min_block;
474 uint32_t max = MIN_NON_ZERO(NBD_MAX_BUFFER_SIZE, s->info.max_block);
475
476 bs->bl.request_alignment = min ? min : BDRV_SECTOR_SIZE;
477 bs->bl.max_pdiscard = max;
478 bs->bl.max_pwrite_zeroes = max;
479 bs->bl.max_transfer = max;
480
481 if (s->info.opt_block &&
482 s->info.opt_block > bs->bl.opt_transfer) {
483 bs->bl.opt_transfer = s->info.opt_block;
484 }
485 }
486
487 static void nbd_close(BlockDriverState *bs)
488 {
489 BDRVNBDState *s = bs->opaque;
490
491 nbd_client_close(bs);
492
493 qapi_free_SocketAddress(s->saddr);
494 g_free(s->export);
495 g_free(s->tlscredsid);
496 }
497
498 static int64_t nbd_getlength(BlockDriverState *bs)
499 {
500 BDRVNBDState *s = bs->opaque;
501
502 return s->client.info.size;
503 }
504
505 static void nbd_detach_aio_context(BlockDriverState *bs)
506 {
507 nbd_client_detach_aio_context(bs);
508 }
509
510 static void nbd_attach_aio_context(BlockDriverState *bs,
511 AioContext *new_context)
512 {
513 nbd_client_attach_aio_context(bs, new_context);
514 }
515
516 static void nbd_refresh_filename(BlockDriverState *bs, QDict *options)
517 {
518 BDRVNBDState *s = bs->opaque;
519 QDict *opts = qdict_new();
520 QObject *saddr_qdict;
521 Visitor *ov;
522 const char *host = NULL, *port = NULL, *path = NULL;
523
524 if (s->saddr->type == SOCKET_ADDRESS_TYPE_INET) {
525 const InetSocketAddress *inet = &s->saddr->u.inet;
526 if (!inet->has_ipv4 && !inet->has_ipv6 && !inet->has_to) {
527 host = inet->host;
528 port = inet->port;
529 }
530 } else if (s->saddr->type == SOCKET_ADDRESS_TYPE_UNIX) {
531 path = s->saddr->u.q_unix.path;
532 } /* else can't represent as pseudo-filename */
533
534 qdict_put_str(opts, "driver", "nbd");
535
536 if (path && s->export) {
537 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
538 "nbd+unix:///%s?socket=%s", s->export, path);
539 } else if (path && !s->export) {
540 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
541 "nbd+unix://?socket=%s", path);
542 } else if (host && s->export) {
543 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
544 "nbd://%s:%s/%s", host, port, s->export);
545 } else if (host && !s->export) {
546 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
547 "nbd://%s:%s", host, port);
548 }
549
550 ov = qobject_output_visitor_new(&saddr_qdict);
551 visit_type_SocketAddress(ov, NULL, &s->saddr, &error_abort);
552 visit_complete(ov, &saddr_qdict);
553 visit_free(ov);
554 qdict_put_obj(opts, "server", saddr_qdict);
555
556 if (s->export) {
557 qdict_put_str(opts, "export", s->export);
558 }
559 if (s->tlscredsid) {
560 qdict_put_str(opts, "tls-creds", s->tlscredsid);
561 }
562
563 qdict_flatten(opts);
564 bs->full_open_options = opts;
565 }
566
567 static BlockDriver bdrv_nbd = {
568 .format_name = "nbd",
569 .protocol_name = "nbd",
570 .instance_size = sizeof(BDRVNBDState),
571 .bdrv_parse_filename = nbd_parse_filename,
572 .bdrv_file_open = nbd_open,
573 .bdrv_co_preadv = nbd_client_co_preadv,
574 .bdrv_co_pwritev = nbd_client_co_pwritev,
575 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes,
576 .bdrv_close = nbd_close,
577 .bdrv_co_flush_to_os = nbd_co_flush,
578 .bdrv_co_pdiscard = nbd_client_co_pdiscard,
579 .bdrv_refresh_limits = nbd_refresh_limits,
580 .bdrv_getlength = nbd_getlength,
581 .bdrv_detach_aio_context = nbd_detach_aio_context,
582 .bdrv_attach_aio_context = nbd_attach_aio_context,
583 .bdrv_refresh_filename = nbd_refresh_filename,
584 .bdrv_co_block_status = nbd_client_co_block_status,
585 };
586
587 static BlockDriver bdrv_nbd_tcp = {
588 .format_name = "nbd",
589 .protocol_name = "nbd+tcp",
590 .instance_size = sizeof(BDRVNBDState),
591 .bdrv_parse_filename = nbd_parse_filename,
592 .bdrv_file_open = nbd_open,
593 .bdrv_co_preadv = nbd_client_co_preadv,
594 .bdrv_co_pwritev = nbd_client_co_pwritev,
595 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes,
596 .bdrv_close = nbd_close,
597 .bdrv_co_flush_to_os = nbd_co_flush,
598 .bdrv_co_pdiscard = nbd_client_co_pdiscard,
599 .bdrv_refresh_limits = nbd_refresh_limits,
600 .bdrv_getlength = nbd_getlength,
601 .bdrv_detach_aio_context = nbd_detach_aio_context,
602 .bdrv_attach_aio_context = nbd_attach_aio_context,
603 .bdrv_refresh_filename = nbd_refresh_filename,
604 .bdrv_co_block_status = nbd_client_co_block_status,
605 };
606
607 static BlockDriver bdrv_nbd_unix = {
608 .format_name = "nbd",
609 .protocol_name = "nbd+unix",
610 .instance_size = sizeof(BDRVNBDState),
611 .bdrv_parse_filename = nbd_parse_filename,
612 .bdrv_file_open = nbd_open,
613 .bdrv_co_preadv = nbd_client_co_preadv,
614 .bdrv_co_pwritev = nbd_client_co_pwritev,
615 .bdrv_co_pwrite_zeroes = nbd_client_co_pwrite_zeroes,
616 .bdrv_close = nbd_close,
617 .bdrv_co_flush_to_os = nbd_co_flush,
618 .bdrv_co_pdiscard = nbd_client_co_pdiscard,
619 .bdrv_refresh_limits = nbd_refresh_limits,
620 .bdrv_getlength = nbd_getlength,
621 .bdrv_detach_aio_context = nbd_detach_aio_context,
622 .bdrv_attach_aio_context = nbd_attach_aio_context,
623 .bdrv_refresh_filename = nbd_refresh_filename,
624 .bdrv_co_block_status = nbd_client_co_block_status,
625 };
626
627 static void bdrv_nbd_init(void)
628 {
629 bdrv_register(&bdrv_nbd);
630 bdrv_register(&bdrv_nbd_tcp);
631 bdrv_register(&bdrv_nbd_unix);
632 }
633
634 block_init(bdrv_nbd_init);