Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20200406' into...
[qemu.git] / qemu-nbd.c
1 /*
2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
3 *
4 * Network Block Device
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; under version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #include "qemu/osdep.h"
20 #include <getopt.h>
21 #include <libgen.h>
22 #include <pthread.h>
23
24 #include "qemu-common.h"
25 #include "qapi/error.h"
26 #include "qemu/cutils.h"
27 #include "sysemu/block-backend.h"
28 #include "block/block_int.h"
29 #include "block/nbd.h"
30 #include "qemu/main-loop.h"
31 #include "qemu/module.h"
32 #include "qemu/option.h"
33 #include "qemu/error-report.h"
34 #include "qemu/config-file.h"
35 #include "qemu/bswap.h"
36 #include "qemu/log.h"
37 #include "qemu/systemd.h"
38 #include "block/snapshot.h"
39 #include "qapi/qmp/qdict.h"
40 #include "qapi/qmp/qstring.h"
41 #include "qom/object_interfaces.h"
42 #include "io/channel-socket.h"
43 #include "io/net-listener.h"
44 #include "crypto/init.h"
45 #include "trace/control.h"
46 #include "qemu-version.h"
47
48 #ifdef __linux__
49 #define HAVE_NBD_DEVICE 1
50 #else
51 #define HAVE_NBD_DEVICE 0
52 #endif
53
54 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
55 #define QEMU_NBD_OPT_CACHE 256
56 #define QEMU_NBD_OPT_AIO 257
57 #define QEMU_NBD_OPT_DISCARD 258
58 #define QEMU_NBD_OPT_DETECT_ZEROES 259
59 #define QEMU_NBD_OPT_OBJECT 260
60 #define QEMU_NBD_OPT_TLSCREDS 261
61 #define QEMU_NBD_OPT_IMAGE_OPTS 262
62 #define QEMU_NBD_OPT_FORK 263
63 #define QEMU_NBD_OPT_TLSAUTHZ 264
64 #define QEMU_NBD_OPT_PID_FILE 265
65
66 #define MBR_SIZE 512
67
68 static NBDExport *export;
69 static int verbose;
70 static char *srcpath;
71 static SocketAddress *saddr;
72 static int persistent = 0;
73 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
74 static int shared = 1;
75 static int nb_fds;
76 static QIONetListener *server;
77 static QCryptoTLSCreds *tlscreds;
78 static const char *tlsauthz;
79
80 static void usage(const char *name)
81 {
82 (printf) (
83 "Usage: %s [OPTIONS] FILE\n"
84 " or: %s -L [OPTIONS]\n"
85 "QEMU Disk Network Block Device Utility\n"
86 "\n"
87 " -h, --help display this help and exit\n"
88 " -V, --version output version information and exit\n"
89 "\n"
90 "Connection properties:\n"
91 " -p, --port=PORT port to listen on (default `%d')\n"
92 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
93 " -k, --socket=PATH path to the unix socket\n"
94 " (default '"SOCKET_PATH"')\n"
95 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
96 " -t, --persistent don't exit on the last connection\n"
97 " -v, --verbose display extra debugging information\n"
98 " -x, --export-name=NAME expose export by name (default is empty string)\n"
99 " -D, --description=TEXT export a human-readable description\n"
100 "\n"
101 "Exposing part of the image:\n"
102 " -o, --offset=OFFSET offset into the image\n"
103 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
104 "\n"
105 "General purpose options:\n"
106 " -L, --list list exports available from another NBD server\n"
107 " --object type,id=ID,... define an object such as 'secret' for providing\n"
108 " passwords and/or encryption keys\n"
109 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
110 " --tls-authz=ID use id of an earlier --object to provide\n"
111 " authorization\n"
112 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
113 " specify tracing options\n"
114 " --fork fork off the server process and exit the parent\n"
115 " once the server is running\n"
116 " --pid-file=PATH store the server's process ID in the given file\n"
117 #if HAVE_NBD_DEVICE
118 "\n"
119 "Kernel NBD client support:\n"
120 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
121 " -d, --disconnect disconnect the specified device\n"
122 #endif
123 "\n"
124 "Block device options:\n"
125 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
126 " -r, --read-only export read-only\n"
127 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
128 " file with backing_file=FILE, redirect the write to\n"
129 " the temporary one\n"
130 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
131 " load an internal snapshot inside FILE and export it\n"
132 " as an read-only device, SNAPSHOT_PARAM format is\n"
133 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
134 " '[ID_OR_NAME]'\n"
135 " -n, --nocache disable host cache\n"
136 " --cache=MODE set cache mode (none, writeback, ...)\n"
137 " --aio=MODE set AIO mode (native, io_uring or threads)\n"
138 " --discard=MODE set discard mode (ignore, unmap)\n"
139 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
140 " --image-opts treat FILE as a full set of image options\n"
141 "\n"
142 QEMU_HELP_BOTTOM "\n"
143 , name, name, NBD_DEFAULT_PORT, "DEVICE");
144 }
145
146 static void version(const char *name)
147 {
148 printf(
149 "%s " QEMU_FULL_VERSION "\n"
150 "Written by Anthony Liguori.\n"
151 "\n"
152 QEMU_COPYRIGHT "\n"
153 "This is free software; see the source for copying conditions. There is NO\n"
154 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
155 , name);
156 }
157
158 static void termsig_handler(int signum)
159 {
160 atomic_cmpxchg(&state, RUNNING, TERMINATE);
161 qemu_notify_event();
162 }
163
164
165 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
166 const char *hostname)
167 {
168 int ret = EXIT_FAILURE;
169 int rc;
170 Error *err = NULL;
171 QIOChannelSocket *sioc;
172 NBDExportInfo *list;
173 int i, j;
174
175 sioc = qio_channel_socket_new();
176 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
177 error_report_err(err);
178 return EXIT_FAILURE;
179 }
180 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
181 &err);
182 if (rc < 0) {
183 if (err) {
184 error_report_err(err);
185 }
186 goto out;
187 }
188 printf("exports available: %d\n", rc);
189 for (i = 0; i < rc; i++) {
190 printf(" export: '%s'\n", list[i].name);
191 if (list[i].description && *list[i].description) {
192 printf(" description: %s\n", list[i].description);
193 }
194 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
195 static const char *const flag_names[] = {
196 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
197 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
198 [NBD_FLAG_SEND_FUA_BIT] = "fua",
199 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
200 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
201 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
202 [NBD_FLAG_SEND_DF_BIT] = "df",
203 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
204 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
205 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
206 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
207 };
208
209 printf(" size: %" PRIu64 "\n", list[i].size);
210 printf(" flags: 0x%x (", list[i].flags);
211 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
212 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
213 printf(" %s", flag_names[bit]);
214 }
215 }
216 printf(" )\n");
217 }
218 if (list[i].min_block) {
219 printf(" min block: %u\n", list[i].min_block);
220 printf(" opt block: %u\n", list[i].opt_block);
221 printf(" max block: %u\n", list[i].max_block);
222 }
223 if (list[i].n_contexts) {
224 printf(" available meta contexts: %d\n", list[i].n_contexts);
225 for (j = 0; j < list[i].n_contexts; j++) {
226 printf(" %s\n", list[i].contexts[j]);
227 }
228 }
229 }
230 nbd_free_export_list(list, rc);
231
232 ret = EXIT_SUCCESS;
233 out:
234 object_unref(OBJECT(sioc));
235 return ret;
236 }
237
238
239 #if HAVE_NBD_DEVICE
240 static void *show_parts(void *arg)
241 {
242 char *device = arg;
243 int nbd;
244
245 /* linux just needs an open() to trigger
246 * the partition table update
247 * but remember to load the module with max_part != 0 :
248 * modprobe nbd max_part=63
249 */
250 nbd = open(device, O_RDWR);
251 if (nbd >= 0) {
252 close(nbd);
253 }
254 return NULL;
255 }
256
257 static void *nbd_client_thread(void *arg)
258 {
259 char *device = arg;
260 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
261 QIOChannelSocket *sioc;
262 int fd;
263 int ret;
264 pthread_t show_parts_thread;
265 Error *local_error = NULL;
266
267 sioc = qio_channel_socket_new();
268 if (qio_channel_socket_connect_sync(sioc,
269 saddr,
270 &local_error) < 0) {
271 error_report_err(local_error);
272 goto out;
273 }
274
275 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
276 NULL, NULL, NULL, &info, &local_error);
277 if (ret < 0) {
278 if (local_error) {
279 error_report_err(local_error);
280 }
281 goto out_socket;
282 }
283
284 fd = open(device, O_RDWR);
285 if (fd < 0) {
286 /* Linux-only, we can use %m in printf. */
287 error_report("Failed to open %s: %m", device);
288 goto out_socket;
289 }
290
291 ret = nbd_init(fd, sioc, &info, &local_error);
292 if (ret < 0) {
293 error_report_err(local_error);
294 goto out_fd;
295 }
296
297 /* update partition table */
298 pthread_create(&show_parts_thread, NULL, show_parts, device);
299
300 if (verbose) {
301 fprintf(stderr, "NBD device %s is now connected to %s\n",
302 device, srcpath);
303 } else {
304 /* Close stderr so that the qemu-nbd process exits. */
305 dup2(STDOUT_FILENO, STDERR_FILENO);
306 }
307
308 ret = nbd_client(fd);
309 if (ret) {
310 goto out_fd;
311 }
312 close(fd);
313 object_unref(OBJECT(sioc));
314 g_free(info.name);
315 kill(getpid(), SIGTERM);
316 return (void *) EXIT_SUCCESS;
317
318 out_fd:
319 close(fd);
320 out_socket:
321 object_unref(OBJECT(sioc));
322 out:
323 g_free(info.name);
324 kill(getpid(), SIGTERM);
325 return (void *) EXIT_FAILURE;
326 }
327 #endif /* HAVE_NBD_DEVICE */
328
329 static int nbd_can_accept(void)
330 {
331 return state == RUNNING && nb_fds < shared;
332 }
333
334 static void nbd_export_closed(NBDExport *export)
335 {
336 assert(state == TERMINATING);
337 state = TERMINATED;
338 }
339
340 static void nbd_update_server_watch(void);
341
342 static void nbd_client_closed(NBDClient *client, bool negotiated)
343 {
344 nb_fds--;
345 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
346 state = TERMINATE;
347 }
348 nbd_update_server_watch();
349 nbd_client_put(client);
350 }
351
352 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
353 gpointer opaque)
354 {
355 if (state >= TERMINATE) {
356 return;
357 }
358
359 nb_fds++;
360 nbd_update_server_watch();
361 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
362 }
363
364 static void nbd_update_server_watch(void)
365 {
366 if (nbd_can_accept()) {
367 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
368 } else {
369 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
370 }
371 }
372
373
374 static SocketAddress *nbd_build_socket_address(const char *sockpath,
375 const char *bindto,
376 const char *port)
377 {
378 SocketAddress *saddr;
379
380 saddr = g_new0(SocketAddress, 1);
381 if (sockpath) {
382 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
383 saddr->u.q_unix.path = g_strdup(sockpath);
384 } else {
385 InetSocketAddress *inet;
386 saddr->type = SOCKET_ADDRESS_TYPE_INET;
387 inet = &saddr->u.inet;
388 inet->host = g_strdup(bindto);
389 if (port) {
390 inet->port = g_strdup(port);
391 } else {
392 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
393 }
394 }
395
396 return saddr;
397 }
398
399
400 static QemuOptsList file_opts = {
401 .name = "file",
402 .implied_opt_name = "file",
403 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
404 .desc = {
405 /* no elements => accept any params */
406 { /* end of list */ }
407 },
408 };
409
410 static QemuOptsList qemu_object_opts = {
411 .name = "object",
412 .implied_opt_name = "qom-type",
413 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
414 .desc = {
415 { }
416 },
417 };
418
419 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
420 {
421 if (user_creatable_print_help(type, opts)) {
422 exit(0);
423 }
424 return true;
425 }
426
427
428 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
429 Error **errp)
430 {
431 Object *obj;
432 QCryptoTLSCreds *creds;
433
434 obj = object_resolve_path_component(
435 object_get_objects_root(), id);
436 if (!obj) {
437 error_setg(errp, "No TLS credentials with id '%s'",
438 id);
439 return NULL;
440 }
441 creds = (QCryptoTLSCreds *)
442 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
443 if (!creds) {
444 error_setg(errp, "Object with id '%s' is not TLS credentials",
445 id);
446 return NULL;
447 }
448
449 if (list) {
450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
451 error_setg(errp,
452 "Expecting TLS credentials with a client endpoint");
453 return NULL;
454 }
455 } else {
456 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
457 error_setg(errp,
458 "Expecting TLS credentials with a server endpoint");
459 return NULL;
460 }
461 }
462 object_ref(obj);
463 return creds;
464 }
465
466 static void setup_address_and_port(const char **address, const char **port)
467 {
468 if (*address == NULL) {
469 *address = "0.0.0.0";
470 }
471
472 if (*port == NULL) {
473 *port = stringify(NBD_DEFAULT_PORT);
474 }
475 }
476
477 /*
478 * Check socket parameters compatibility when socket activation is used.
479 */
480 static const char *socket_activation_validate_opts(const char *device,
481 const char *sockpath,
482 const char *address,
483 const char *port,
484 bool list)
485 {
486 if (device != NULL) {
487 return "NBD device can't be set when using socket activation";
488 }
489
490 if (sockpath != NULL) {
491 return "Unix socket can't be set when using socket activation";
492 }
493
494 if (address != NULL) {
495 return "The interface can't be set when using socket activation";
496 }
497
498 if (port != NULL) {
499 return "TCP port number can't be set when using socket activation";
500 }
501
502 if (list) {
503 return "List mode is incompatible with socket activation";
504 }
505
506 return NULL;
507 }
508
509 static void qemu_nbd_shutdown(void)
510 {
511 job_cancel_sync_all();
512 bdrv_close_all();
513 }
514
515 int main(int argc, char **argv)
516 {
517 BlockBackend *blk;
518 BlockDriverState *bs;
519 uint64_t dev_offset = 0;
520 bool readonly = false;
521 bool disconnect = false;
522 const char *bindto = NULL;
523 const char *port = NULL;
524 char *sockpath = NULL;
525 char *device = NULL;
526 int64_t fd_size;
527 QemuOpts *sn_opts = NULL;
528 const char *sn_id_or_name = NULL;
529 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L";
530 struct option lopt[] = {
531 { "help", no_argument, NULL, 'h' },
532 { "version", no_argument, NULL, 'V' },
533 { "bind", required_argument, NULL, 'b' },
534 { "port", required_argument, NULL, 'p' },
535 { "socket", required_argument, NULL, 'k' },
536 { "offset", required_argument, NULL, 'o' },
537 { "read-only", no_argument, NULL, 'r' },
538 { "bitmap", required_argument, NULL, 'B' },
539 { "connect", required_argument, NULL, 'c' },
540 { "disconnect", no_argument, NULL, 'd' },
541 { "list", no_argument, NULL, 'L' },
542 { "snapshot", no_argument, NULL, 's' },
543 { "load-snapshot", required_argument, NULL, 'l' },
544 { "nocache", no_argument, NULL, 'n' },
545 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
546 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
547 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
548 { "detect-zeroes", required_argument, NULL,
549 QEMU_NBD_OPT_DETECT_ZEROES },
550 { "shared", required_argument, NULL, 'e' },
551 { "format", required_argument, NULL, 'f' },
552 { "persistent", no_argument, NULL, 't' },
553 { "verbose", no_argument, NULL, 'v' },
554 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
555 { "export-name", required_argument, NULL, 'x' },
556 { "description", required_argument, NULL, 'D' },
557 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
558 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
559 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
560 { "trace", required_argument, NULL, 'T' },
561 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
562 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
563 { NULL, 0, NULL, 0 }
564 };
565 int ch;
566 int opt_ind = 0;
567 int flags = BDRV_O_RDWR;
568 int ret = 0;
569 bool seen_cache = false;
570 bool seen_discard = false;
571 bool seen_aio = false;
572 pthread_t client_thread;
573 const char *fmt = NULL;
574 Error *local_err = NULL;
575 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
576 QDict *options = NULL;
577 const char *export_name = NULL; /* defaults to "" later for server mode */
578 const char *export_description = NULL;
579 const char *bitmap = NULL;
580 const char *tlscredsid = NULL;
581 bool imageOpts = false;
582 bool writethrough = true;
583 char *trace_file = NULL;
584 bool fork_process = false;
585 bool list = false;
586 int old_stderr = -1;
587 unsigned socket_activation;
588 const char *pid_file_name = NULL;
589
590 /* The client thread uses SIGTERM to interrupt the server. A signal
591 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
592 */
593 struct sigaction sa_sigterm;
594 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
595 sa_sigterm.sa_handler = termsig_handler;
596 sigaction(SIGTERM, &sa_sigterm, NULL);
597
598 #ifdef CONFIG_POSIX
599 signal(SIGPIPE, SIG_IGN);
600 #endif
601
602 error_init(argv[0]);
603 module_call_init(MODULE_INIT_TRACE);
604 qcrypto_init(&error_fatal);
605
606 module_call_init(MODULE_INIT_QOM);
607 qemu_add_opts(&qemu_object_opts);
608 qemu_add_opts(&qemu_trace_opts);
609 qemu_init_exec_dir(argv[0]);
610
611 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
612 switch (ch) {
613 case 's':
614 flags |= BDRV_O_SNAPSHOT;
615 break;
616 case 'n':
617 optarg = (char *) "none";
618 /* fallthrough */
619 case QEMU_NBD_OPT_CACHE:
620 if (seen_cache) {
621 error_report("-n and --cache can only be specified once");
622 exit(EXIT_FAILURE);
623 }
624 seen_cache = true;
625 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
626 error_report("Invalid cache mode `%s'", optarg);
627 exit(EXIT_FAILURE);
628 }
629 break;
630 case QEMU_NBD_OPT_AIO:
631 if (seen_aio) {
632 error_report("--aio can only be specified once");
633 exit(EXIT_FAILURE);
634 }
635 seen_aio = true;
636 if (bdrv_parse_aio(optarg, &flags) < 0) {
637 error_report("Invalid aio mode '%s'", optarg);
638 exit(EXIT_FAILURE);
639 }
640 break;
641 case QEMU_NBD_OPT_DISCARD:
642 if (seen_discard) {
643 error_report("--discard can only be specified once");
644 exit(EXIT_FAILURE);
645 }
646 seen_discard = true;
647 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
648 error_report("Invalid discard mode `%s'", optarg);
649 exit(EXIT_FAILURE);
650 }
651 break;
652 case QEMU_NBD_OPT_DETECT_ZEROES:
653 detect_zeroes =
654 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
655 optarg,
656 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
657 &local_err);
658 if (local_err) {
659 error_reportf_err(local_err,
660 "Failed to parse detect_zeroes mode: ");
661 exit(EXIT_FAILURE);
662 }
663 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
664 !(flags & BDRV_O_UNMAP)) {
665 error_report("setting detect-zeroes to unmap is not allowed "
666 "without setting discard operation to unmap");
667 exit(EXIT_FAILURE);
668 }
669 break;
670 case 'b':
671 bindto = optarg;
672 break;
673 case 'p':
674 port = optarg;
675 break;
676 case 'o':
677 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
678 error_report("Invalid offset '%s'", optarg);
679 exit(EXIT_FAILURE);
680 }
681 break;
682 case 'l':
683 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
684 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
685 optarg, false);
686 if (!sn_opts) {
687 error_report("Failed in parsing snapshot param `%s'",
688 optarg);
689 exit(EXIT_FAILURE);
690 }
691 } else {
692 sn_id_or_name = optarg;
693 }
694 /* fall through */
695 case 'r':
696 readonly = true;
697 flags &= ~BDRV_O_RDWR;
698 break;
699 case 'B':
700 bitmap = optarg;
701 break;
702 case 'k':
703 sockpath = optarg;
704 if (sockpath[0] != '/') {
705 error_report("socket path must be absolute");
706 exit(EXIT_FAILURE);
707 }
708 break;
709 case 'd':
710 disconnect = true;
711 break;
712 case 'c':
713 device = optarg;
714 break;
715 case 'e':
716 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
717 shared < 1) {
718 error_report("Invalid shared device number '%s'", optarg);
719 exit(EXIT_FAILURE);
720 }
721 break;
722 case 'f':
723 fmt = optarg;
724 break;
725 case 't':
726 persistent = 1;
727 break;
728 case 'x':
729 export_name = optarg;
730 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
731 error_report("export name '%s' too long", export_name);
732 exit(EXIT_FAILURE);
733 }
734 break;
735 case 'D':
736 export_description = optarg;
737 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
738 error_report("export description '%s' too long",
739 export_description);
740 exit(EXIT_FAILURE);
741 }
742 break;
743 case 'v':
744 verbose = 1;
745 break;
746 case 'V':
747 version(argv[0]);
748 exit(0);
749 break;
750 case 'h':
751 usage(argv[0]);
752 exit(0);
753 break;
754 case '?':
755 error_report("Try `%s --help' for more information.", argv[0]);
756 exit(EXIT_FAILURE);
757 case QEMU_NBD_OPT_OBJECT: {
758 QemuOpts *opts;
759 opts = qemu_opts_parse_noisily(&qemu_object_opts,
760 optarg, true);
761 if (!opts) {
762 exit(EXIT_FAILURE);
763 }
764 } break;
765 case QEMU_NBD_OPT_TLSCREDS:
766 tlscredsid = optarg;
767 break;
768 case QEMU_NBD_OPT_IMAGE_OPTS:
769 imageOpts = true;
770 break;
771 case 'T':
772 g_free(trace_file);
773 trace_file = trace_opt_parse(optarg);
774 break;
775 case QEMU_NBD_OPT_TLSAUTHZ:
776 tlsauthz = optarg;
777 break;
778 case QEMU_NBD_OPT_FORK:
779 fork_process = true;
780 break;
781 case 'L':
782 list = true;
783 break;
784 case QEMU_NBD_OPT_PID_FILE:
785 pid_file_name = optarg;
786 break;
787 }
788 }
789
790 if (list) {
791 if (argc != optind) {
792 error_report("List mode is incompatible with a file name");
793 exit(EXIT_FAILURE);
794 }
795 if (export_name || export_description || dev_offset ||
796 device || disconnect || fmt || sn_id_or_name || bitmap ||
797 seen_aio || seen_discard || seen_cache) {
798 error_report("List mode is incompatible with per-device settings");
799 exit(EXIT_FAILURE);
800 }
801 if (fork_process) {
802 error_report("List mode is incompatible with forking");
803 exit(EXIT_FAILURE);
804 }
805 } else if ((argc - optind) != 1) {
806 error_report("Invalid number of arguments");
807 error_printf("Try `%s --help' for more information.\n", argv[0]);
808 exit(EXIT_FAILURE);
809 } else if (!export_name) {
810 export_name = "";
811 }
812
813 qemu_opts_foreach(&qemu_object_opts,
814 user_creatable_add_opts_foreach,
815 qemu_nbd_object_print_help, &error_fatal);
816
817 if (!trace_init_backends()) {
818 exit(1);
819 }
820 trace_init_file(trace_file);
821 qemu_set_log(LOG_TRACE);
822
823 socket_activation = check_socket_activation();
824 if (socket_activation == 0) {
825 setup_address_and_port(&bindto, &port);
826 } else {
827 /* Using socket activation - check user didn't use -p etc. */
828 const char *err_msg = socket_activation_validate_opts(device, sockpath,
829 bindto, port,
830 list);
831 if (err_msg != NULL) {
832 error_report("%s", err_msg);
833 exit(EXIT_FAILURE);
834 }
835
836 /* qemu-nbd can only listen on a single socket. */
837 if (socket_activation > 1) {
838 error_report("qemu-nbd does not support socket activation with %s > 1",
839 "LISTEN_FDS");
840 exit(EXIT_FAILURE);
841 }
842 }
843
844 if (tlscredsid) {
845 if (sockpath) {
846 error_report("TLS is only supported with IPv4/IPv6");
847 exit(EXIT_FAILURE);
848 }
849 if (device) {
850 error_report("TLS is not supported with a host device");
851 exit(EXIT_FAILURE);
852 }
853 if (tlsauthz && list) {
854 error_report("TLS authorization is incompatible with export list");
855 exit(EXIT_FAILURE);
856 }
857 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
858 if (local_err) {
859 error_report("Failed to get TLS creds %s",
860 error_get_pretty(local_err));
861 exit(EXIT_FAILURE);
862 }
863 } else {
864 if (tlsauthz) {
865 error_report("--tls-authz is not permitted without --tls-creds");
866 exit(EXIT_FAILURE);
867 }
868 }
869
870 if (list) {
871 saddr = nbd_build_socket_address(sockpath, bindto, port);
872 return qemu_nbd_client_list(saddr, tlscreds, bindto);
873 }
874
875 #if !HAVE_NBD_DEVICE
876 if (disconnect || device) {
877 error_report("Kernel /dev/nbdN support not available");
878 exit(EXIT_FAILURE);
879 }
880 #else /* HAVE_NBD_DEVICE */
881 if (disconnect) {
882 int nbdfd = open(argv[optind], O_RDWR);
883 if (nbdfd < 0) {
884 error_report("Cannot open %s: %s", argv[optind],
885 strerror(errno));
886 exit(EXIT_FAILURE);
887 }
888 nbd_disconnect(nbdfd);
889
890 close(nbdfd);
891
892 printf("%s disconnected\n", argv[optind]);
893
894 return 0;
895 }
896 #endif
897
898 if ((device && !verbose) || fork_process) {
899 int stderr_fd[2];
900 pid_t pid;
901 int ret;
902
903 if (qemu_pipe(stderr_fd) < 0) {
904 error_report("Error setting up communication pipe: %s",
905 strerror(errno));
906 exit(EXIT_FAILURE);
907 }
908
909 /* Now daemonize, but keep a communication channel open to
910 * print errors and exit with the proper status code.
911 */
912 pid = fork();
913 if (pid < 0) {
914 error_report("Failed to fork: %s", strerror(errno));
915 exit(EXIT_FAILURE);
916 } else if (pid == 0) {
917 close(stderr_fd[0]);
918
919 old_stderr = dup(STDERR_FILENO);
920 ret = qemu_daemon(1, 0);
921
922 /* Temporarily redirect stderr to the parent's pipe... */
923 dup2(stderr_fd[1], STDERR_FILENO);
924 if (ret < 0) {
925 error_report("Failed to daemonize: %s", strerror(errno));
926 exit(EXIT_FAILURE);
927 }
928
929 /* ... close the descriptor we inherited and go on. */
930 close(stderr_fd[1]);
931 } else {
932 bool errors = false;
933 char *buf;
934
935 /* In the parent. Print error messages from the child until
936 * it closes the pipe.
937 */
938 close(stderr_fd[1]);
939 buf = g_malloc(1024);
940 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
941 errors = true;
942 ret = qemu_write_full(STDERR_FILENO, buf, ret);
943 if (ret < 0) {
944 exit(EXIT_FAILURE);
945 }
946 }
947 if (ret < 0) {
948 error_report("Cannot read from daemon: %s",
949 strerror(errno));
950 exit(EXIT_FAILURE);
951 }
952
953 /* Usually the daemon should not print any message.
954 * Exit with zero status in that case.
955 */
956 exit(errors);
957 }
958 }
959
960 if (device != NULL && sockpath == NULL) {
961 sockpath = g_malloc(128);
962 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
963 }
964
965 server = qio_net_listener_new();
966 if (socket_activation == 0) {
967 saddr = nbd_build_socket_address(sockpath, bindto, port);
968 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) {
969 object_unref(OBJECT(server));
970 error_report_err(local_err);
971 exit(EXIT_FAILURE);
972 }
973 } else {
974 size_t i;
975 /* See comment in check_socket_activation above. */
976 for (i = 0; i < socket_activation; i++) {
977 QIOChannelSocket *sioc;
978 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
979 &local_err);
980 if (sioc == NULL) {
981 object_unref(OBJECT(server));
982 error_report("Failed to use socket activation: %s",
983 error_get_pretty(local_err));
984 exit(EXIT_FAILURE);
985 }
986 qio_net_listener_add(server, sioc);
987 object_unref(OBJECT(sioc));
988 }
989 }
990
991 if (qemu_init_main_loop(&local_err)) {
992 error_report_err(local_err);
993 exit(EXIT_FAILURE);
994 }
995 bdrv_init();
996 atexit(qemu_nbd_shutdown);
997
998 srcpath = argv[optind];
999 if (imageOpts) {
1000 QemuOpts *opts;
1001 if (fmt) {
1002 error_report("--image-opts and -f are mutually exclusive");
1003 exit(EXIT_FAILURE);
1004 }
1005 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1006 if (!opts) {
1007 qemu_opts_reset(&file_opts);
1008 exit(EXIT_FAILURE);
1009 }
1010 options = qemu_opts_to_qdict(opts, NULL);
1011 qemu_opts_reset(&file_opts);
1012 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1013 } else {
1014 if (fmt) {
1015 options = qdict_new();
1016 qdict_put_str(options, "driver", fmt);
1017 }
1018 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1019 }
1020
1021 if (!blk) {
1022 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1023 argv[optind]);
1024 exit(EXIT_FAILURE);
1025 }
1026 bs = blk_bs(blk);
1027
1028 blk_set_enable_write_cache(blk, !writethrough);
1029
1030 if (sn_opts) {
1031 ret = bdrv_snapshot_load_tmp(bs,
1032 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1033 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1034 &local_err);
1035 } else if (sn_id_or_name) {
1036 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1037 &local_err);
1038 }
1039 if (ret < 0) {
1040 error_reportf_err(local_err, "Failed to load snapshot: ");
1041 exit(EXIT_FAILURE);
1042 }
1043
1044 bs->detect_zeroes = detect_zeroes;
1045 fd_size = blk_getlength(blk);
1046 if (fd_size < 0) {
1047 error_report("Failed to determine the image length: %s",
1048 strerror(-fd_size));
1049 exit(EXIT_FAILURE);
1050 }
1051
1052 if (dev_offset >= fd_size) {
1053 error_report("Offset (%" PRIu64 ") has to be smaller than the image "
1054 "size (%" PRId64 ")", dev_offset, fd_size);
1055 exit(EXIT_FAILURE);
1056 }
1057 fd_size -= dev_offset;
1058
1059 export = nbd_export_new(bs, dev_offset, fd_size, export_name,
1060 export_description, bitmap, readonly, shared > 1,
1061 nbd_export_closed, writethrough, NULL,
1062 &error_fatal);
1063
1064 if (device) {
1065 #if HAVE_NBD_DEVICE
1066 int ret;
1067
1068 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1069 if (ret != 0) {
1070 error_report("Failed to create client thread: %s", strerror(ret));
1071 exit(EXIT_FAILURE);
1072 }
1073 #endif
1074 } else {
1075 /* Shut up GCC warnings. */
1076 memset(&client_thread, 0, sizeof(client_thread));
1077 }
1078
1079 nbd_update_server_watch();
1080
1081 if (pid_file_name) {
1082 qemu_write_pidfile(pid_file_name, &error_fatal);
1083 }
1084
1085 /* now when the initialization is (almost) complete, chdir("/")
1086 * to free any busy filesystems */
1087 if (chdir("/") < 0) {
1088 error_report("Could not chdir to root directory: %s",
1089 strerror(errno));
1090 exit(EXIT_FAILURE);
1091 }
1092
1093 if (fork_process) {
1094 dup2(old_stderr, STDERR_FILENO);
1095 close(old_stderr);
1096 }
1097
1098 state = RUNNING;
1099 do {
1100 main_loop_wait(false);
1101 if (state == TERMINATE) {
1102 state = TERMINATING;
1103 nbd_export_close(export);
1104 nbd_export_put(export);
1105 export = NULL;
1106 }
1107 } while (state != TERMINATED);
1108
1109 blk_unref(blk);
1110 if (sockpath) {
1111 unlink(sockpath);
1112 }
1113
1114 qemu_opts_del(sn_opts);
1115
1116 if (device) {
1117 void *ret;
1118 pthread_join(client_thread, &ret);
1119 exit(ret != NULL);
1120 } else {
1121 exit(EXIT_SUCCESS);
1122 }
1123 }