qemu-img: add support for rate limit in qemu-img commit
[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 "sysemu/runstate.h" /* for qemu_system_killed() prototype */
29 #include "block/block_int.h"
30 #include "block/nbd.h"
31 #include "qemu/main-loop.h"
32 #include "qemu/module.h"
33 #include "qemu/option.h"
34 #include "qemu/error-report.h"
35 #include "qemu/config-file.h"
36 #include "qemu/bswap.h"
37 #include "qemu/log.h"
38 #include "qemu/systemd.h"
39 #include "block/snapshot.h"
40 #include "qapi/qmp/qdict.h"
41 #include "qapi/qmp/qstring.h"
42 #include "qom/object_interfaces.h"
43 #include "io/channel-socket.h"
44 #include "io/net-listener.h"
45 #include "crypto/init.h"
46 #include "trace/control.h"
47 #include "qemu-version.h"
48
49 #ifdef __linux__
50 #define HAVE_NBD_DEVICE 1
51 #else
52 #define HAVE_NBD_DEVICE 0
53 #endif
54
55 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
56 #define QEMU_NBD_OPT_CACHE 256
57 #define QEMU_NBD_OPT_AIO 257
58 #define QEMU_NBD_OPT_DISCARD 258
59 #define QEMU_NBD_OPT_DETECT_ZEROES 259
60 #define QEMU_NBD_OPT_OBJECT 260
61 #define QEMU_NBD_OPT_TLSCREDS 261
62 #define QEMU_NBD_OPT_IMAGE_OPTS 262
63 #define QEMU_NBD_OPT_FORK 263
64 #define QEMU_NBD_OPT_TLSAUTHZ 264
65 #define QEMU_NBD_OPT_PID_FILE 265
66
67 #define MBR_SIZE 512
68
69 static int verbose;
70 static char *srcpath;
71 static SocketAddress *saddr;
72 static int persistent = 0;
73 static enum { RUNNING, TERMINATE, 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 #ifdef CONFIG_POSIX
159 /*
160 * The client thread uses SIGTERM to interrupt the server. A signal
161 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
162 */
163 void qemu_system_killed(int signum, pid_t pid)
164 {
165 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
166 qemu_notify_event();
167 }
168 #endif /* CONFIG_POSIX */
169
170 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
171 const char *hostname)
172 {
173 int ret = EXIT_FAILURE;
174 int rc;
175 Error *err = NULL;
176 QIOChannelSocket *sioc;
177 NBDExportInfo *list;
178 int i, j;
179
180 sioc = qio_channel_socket_new();
181 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
182 error_report_err(err);
183 return EXIT_FAILURE;
184 }
185 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
186 &err);
187 if (rc < 0) {
188 if (err) {
189 error_report_err(err);
190 }
191 goto out;
192 }
193 printf("exports available: %d\n", rc);
194 for (i = 0; i < rc; i++) {
195 printf(" export: '%s'\n", list[i].name);
196 if (list[i].description && *list[i].description) {
197 printf(" description: %s\n", list[i].description);
198 }
199 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
200 static const char *const flag_names[] = {
201 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
202 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
203 [NBD_FLAG_SEND_FUA_BIT] = "fua",
204 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
205 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
206 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
207 [NBD_FLAG_SEND_DF_BIT] = "df",
208 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
209 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
210 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
211 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
212 };
213
214 printf(" size: %" PRIu64 "\n", list[i].size);
215 printf(" flags: 0x%x (", list[i].flags);
216 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
217 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
218 printf(" %s", flag_names[bit]);
219 }
220 }
221 printf(" )\n");
222 }
223 if (list[i].min_block) {
224 printf(" min block: %u\n", list[i].min_block);
225 printf(" opt block: %u\n", list[i].opt_block);
226 printf(" max block: %u\n", list[i].max_block);
227 }
228 if (list[i].n_contexts) {
229 printf(" available meta contexts: %d\n", list[i].n_contexts);
230 for (j = 0; j < list[i].n_contexts; j++) {
231 printf(" %s\n", list[i].contexts[j]);
232 }
233 }
234 }
235 nbd_free_export_list(list, rc);
236
237 ret = EXIT_SUCCESS;
238 out:
239 object_unref(OBJECT(sioc));
240 return ret;
241 }
242
243
244 #if HAVE_NBD_DEVICE
245 static void *show_parts(void *arg)
246 {
247 char *device = arg;
248 int nbd;
249
250 /* linux just needs an open() to trigger
251 * the partition table update
252 * but remember to load the module with max_part != 0 :
253 * modprobe nbd max_part=63
254 */
255 nbd = open(device, O_RDWR);
256 if (nbd >= 0) {
257 close(nbd);
258 }
259 return NULL;
260 }
261
262 static void *nbd_client_thread(void *arg)
263 {
264 char *device = arg;
265 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
266 QIOChannelSocket *sioc;
267 int fd;
268 int ret;
269 pthread_t show_parts_thread;
270 Error *local_error = NULL;
271
272 sioc = qio_channel_socket_new();
273 if (qio_channel_socket_connect_sync(sioc,
274 saddr,
275 &local_error) < 0) {
276 error_report_err(local_error);
277 goto out;
278 }
279
280 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
281 NULL, NULL, NULL, &info, &local_error);
282 if (ret < 0) {
283 if (local_error) {
284 error_report_err(local_error);
285 }
286 goto out_socket;
287 }
288
289 fd = open(device, O_RDWR);
290 if (fd < 0) {
291 /* Linux-only, we can use %m in printf. */
292 error_report("Failed to open %s: %m", device);
293 goto out_socket;
294 }
295
296 ret = nbd_init(fd, sioc, &info, &local_error);
297 if (ret < 0) {
298 error_report_err(local_error);
299 goto out_fd;
300 }
301
302 /* update partition table */
303 pthread_create(&show_parts_thread, NULL, show_parts, device);
304
305 if (verbose) {
306 fprintf(stderr, "NBD device %s is now connected to %s\n",
307 device, srcpath);
308 } else {
309 /* Close stderr so that the qemu-nbd process exits. */
310 dup2(STDOUT_FILENO, STDERR_FILENO);
311 }
312
313 ret = nbd_client(fd);
314 if (ret) {
315 goto out_fd;
316 }
317 close(fd);
318 object_unref(OBJECT(sioc));
319 g_free(info.name);
320 kill(getpid(), SIGTERM);
321 return (void *) EXIT_SUCCESS;
322
323 out_fd:
324 close(fd);
325 out_socket:
326 object_unref(OBJECT(sioc));
327 out:
328 g_free(info.name);
329 kill(getpid(), SIGTERM);
330 return (void *) EXIT_FAILURE;
331 }
332 #endif /* HAVE_NBD_DEVICE */
333
334 static int nbd_can_accept(void)
335 {
336 return state == RUNNING && nb_fds < shared;
337 }
338
339 static void nbd_update_server_watch(void);
340
341 static void nbd_client_closed(NBDClient *client, bool negotiated)
342 {
343 nb_fds--;
344 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
345 state = TERMINATE;
346 }
347 nbd_update_server_watch();
348 nbd_client_put(client);
349 }
350
351 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
352 gpointer opaque)
353 {
354 if (state >= TERMINATE) {
355 return;
356 }
357
358 nb_fds++;
359 nbd_update_server_watch();
360 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
361 }
362
363 static void nbd_update_server_watch(void)
364 {
365 if (nbd_can_accept()) {
366 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
367 } else {
368 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
369 }
370 }
371
372
373 static SocketAddress *nbd_build_socket_address(const char *sockpath,
374 const char *bindto,
375 const char *port)
376 {
377 SocketAddress *saddr;
378
379 saddr = g_new0(SocketAddress, 1);
380 if (sockpath) {
381 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
382 saddr->u.q_unix.path = g_strdup(sockpath);
383 } else {
384 InetSocketAddress *inet;
385 saddr->type = SOCKET_ADDRESS_TYPE_INET;
386 inet = &saddr->u.inet;
387 inet->host = g_strdup(bindto);
388 if (port) {
389 inet->port = g_strdup(port);
390 } else {
391 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
392 }
393 }
394
395 return saddr;
396 }
397
398
399 static QemuOptsList file_opts = {
400 .name = "file",
401 .implied_opt_name = "file",
402 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
403 .desc = {
404 /* no elements => accept any params */
405 { /* end of list */ }
406 },
407 };
408
409 static QemuOptsList qemu_object_opts = {
410 .name = "object",
411 .implied_opt_name = "qom-type",
412 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
413 .desc = {
414 { }
415 },
416 };
417
418 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
419 {
420 if (user_creatable_print_help(type, opts)) {
421 exit(0);
422 }
423 return true;
424 }
425
426
427 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
428 Error **errp)
429 {
430 Object *obj;
431 QCryptoTLSCreds *creds;
432
433 obj = object_resolve_path_component(
434 object_get_objects_root(), id);
435 if (!obj) {
436 error_setg(errp, "No TLS credentials with id '%s'",
437 id);
438 return NULL;
439 }
440 creds = (QCryptoTLSCreds *)
441 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
442 if (!creds) {
443 error_setg(errp, "Object with id '%s' is not TLS credentials",
444 id);
445 return NULL;
446 }
447
448 if (list) {
449 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
450 error_setg(errp,
451 "Expecting TLS credentials with a client endpoint");
452 return NULL;
453 }
454 } else {
455 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
456 error_setg(errp,
457 "Expecting TLS credentials with a server endpoint");
458 return NULL;
459 }
460 }
461 object_ref(obj);
462 return creds;
463 }
464
465 static void setup_address_and_port(const char **address, const char **port)
466 {
467 if (*address == NULL) {
468 *address = "0.0.0.0";
469 }
470
471 if (*port == NULL) {
472 *port = stringify(NBD_DEFAULT_PORT);
473 }
474 }
475
476 /*
477 * Check socket parameters compatibility when socket activation is used.
478 */
479 static const char *socket_activation_validate_opts(const char *device,
480 const char *sockpath,
481 const char *address,
482 const char *port,
483 bool list)
484 {
485 if (device != NULL) {
486 return "NBD device can't be set when using socket activation";
487 }
488
489 if (sockpath != NULL) {
490 return "Unix socket can't be set when using socket activation";
491 }
492
493 if (address != NULL) {
494 return "The interface can't be set when using socket activation";
495 }
496
497 if (port != NULL) {
498 return "TCP port number can't be set when using socket activation";
499 }
500
501 if (list) {
502 return "List mode is incompatible with socket activation";
503 }
504
505 return NULL;
506 }
507
508 static void qemu_nbd_shutdown(void)
509 {
510 job_cancel_sync_all();
511 bdrv_close_all();
512 }
513
514 int main(int argc, char **argv)
515 {
516 BlockBackend *blk;
517 BlockDriverState *bs;
518 uint64_t dev_offset = 0;
519 bool readonly = false;
520 bool disconnect = false;
521 const char *bindto = NULL;
522 const char *port = NULL;
523 char *sockpath = NULL;
524 char *device = NULL;
525 QemuOpts *sn_opts = NULL;
526 const char *sn_id_or_name = NULL;
527 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L";
528 struct option lopt[] = {
529 { "help", no_argument, NULL, 'h' },
530 { "version", no_argument, NULL, 'V' },
531 { "bind", required_argument, NULL, 'b' },
532 { "port", required_argument, NULL, 'p' },
533 { "socket", required_argument, NULL, 'k' },
534 { "offset", required_argument, NULL, 'o' },
535 { "read-only", no_argument, NULL, 'r' },
536 { "bitmap", required_argument, NULL, 'B' },
537 { "connect", required_argument, NULL, 'c' },
538 { "disconnect", no_argument, NULL, 'd' },
539 { "list", no_argument, NULL, 'L' },
540 { "snapshot", no_argument, NULL, 's' },
541 { "load-snapshot", required_argument, NULL, 'l' },
542 { "nocache", no_argument, NULL, 'n' },
543 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
544 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
545 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
546 { "detect-zeroes", required_argument, NULL,
547 QEMU_NBD_OPT_DETECT_ZEROES },
548 { "shared", required_argument, NULL, 'e' },
549 { "format", required_argument, NULL, 'f' },
550 { "persistent", no_argument, NULL, 't' },
551 { "verbose", no_argument, NULL, 'v' },
552 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
553 { "export-name", required_argument, NULL, 'x' },
554 { "description", required_argument, NULL, 'D' },
555 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
556 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
557 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
558 { "trace", required_argument, NULL, 'T' },
559 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
560 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
561 { NULL, 0, NULL, 0 }
562 };
563 int ch;
564 int opt_ind = 0;
565 int flags = BDRV_O_RDWR;
566 int ret = 0;
567 bool seen_cache = false;
568 bool seen_discard = false;
569 bool seen_aio = false;
570 pthread_t client_thread;
571 const char *fmt = NULL;
572 Error *local_err = NULL;
573 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
574 QDict *options = NULL;
575 const char *export_name = NULL; /* defaults to "" later for server mode */
576 const char *export_description = NULL;
577 const char *bitmap = NULL;
578 const char *tlscredsid = NULL;
579 bool imageOpts = false;
580 bool writethrough = true;
581 char *trace_file = NULL;
582 bool fork_process = false;
583 bool list = false;
584 int old_stderr = -1;
585 unsigned socket_activation;
586 const char *pid_file_name = NULL;
587 BlockExportOptions *export_opts;
588
589 #ifdef CONFIG_POSIX
590 os_setup_early_signal_handling();
591 os_setup_signal_handling();
592 #endif
593
594 socket_init();
595 error_init(argv[0]);
596 module_call_init(MODULE_INIT_TRACE);
597 qcrypto_init(&error_fatal);
598
599 module_call_init(MODULE_INIT_QOM);
600 qemu_add_opts(&qemu_object_opts);
601 qemu_add_opts(&qemu_trace_opts);
602 qemu_init_exec_dir(argv[0]);
603
604 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
605 switch (ch) {
606 case 's':
607 flags |= BDRV_O_SNAPSHOT;
608 break;
609 case 'n':
610 optarg = (char *) "none";
611 /* fallthrough */
612 case QEMU_NBD_OPT_CACHE:
613 if (seen_cache) {
614 error_report("-n and --cache can only be specified once");
615 exit(EXIT_FAILURE);
616 }
617 seen_cache = true;
618 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
619 error_report("Invalid cache mode `%s'", optarg);
620 exit(EXIT_FAILURE);
621 }
622 break;
623 case QEMU_NBD_OPT_AIO:
624 if (seen_aio) {
625 error_report("--aio can only be specified once");
626 exit(EXIT_FAILURE);
627 }
628 seen_aio = true;
629 if (bdrv_parse_aio(optarg, &flags) < 0) {
630 error_report("Invalid aio mode '%s'", optarg);
631 exit(EXIT_FAILURE);
632 }
633 break;
634 case QEMU_NBD_OPT_DISCARD:
635 if (seen_discard) {
636 error_report("--discard can only be specified once");
637 exit(EXIT_FAILURE);
638 }
639 seen_discard = true;
640 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
641 error_report("Invalid discard mode `%s'", optarg);
642 exit(EXIT_FAILURE);
643 }
644 break;
645 case QEMU_NBD_OPT_DETECT_ZEROES:
646 detect_zeroes =
647 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
648 optarg,
649 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
650 &local_err);
651 if (local_err) {
652 error_reportf_err(local_err,
653 "Failed to parse detect_zeroes mode: ");
654 exit(EXIT_FAILURE);
655 }
656 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
657 !(flags & BDRV_O_UNMAP)) {
658 error_report("setting detect-zeroes to unmap is not allowed "
659 "without setting discard operation to unmap");
660 exit(EXIT_FAILURE);
661 }
662 break;
663 case 'b':
664 bindto = optarg;
665 break;
666 case 'p':
667 port = optarg;
668 break;
669 case 'o':
670 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
671 error_report("Invalid offset '%s'", optarg);
672 exit(EXIT_FAILURE);
673 }
674 break;
675 case 'l':
676 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
677 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
678 optarg, false);
679 if (!sn_opts) {
680 error_report("Failed in parsing snapshot param `%s'",
681 optarg);
682 exit(EXIT_FAILURE);
683 }
684 } else {
685 sn_id_or_name = optarg;
686 }
687 /* fall through */
688 case 'r':
689 readonly = true;
690 flags &= ~BDRV_O_RDWR;
691 break;
692 case 'B':
693 bitmap = optarg;
694 break;
695 case 'k':
696 sockpath = optarg;
697 if (sockpath[0] != '/') {
698 error_report("socket path must be absolute");
699 exit(EXIT_FAILURE);
700 }
701 break;
702 case 'd':
703 disconnect = true;
704 break;
705 case 'c':
706 device = optarg;
707 break;
708 case 'e':
709 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
710 shared < 1) {
711 error_report("Invalid shared device number '%s'", optarg);
712 exit(EXIT_FAILURE);
713 }
714 break;
715 case 'f':
716 fmt = optarg;
717 break;
718 case 't':
719 persistent = 1;
720 break;
721 case 'x':
722 export_name = optarg;
723 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
724 error_report("export name '%s' too long", export_name);
725 exit(EXIT_FAILURE);
726 }
727 break;
728 case 'D':
729 export_description = optarg;
730 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
731 error_report("export description '%s' too long",
732 export_description);
733 exit(EXIT_FAILURE);
734 }
735 break;
736 case 'v':
737 verbose = 1;
738 break;
739 case 'V':
740 version(argv[0]);
741 exit(0);
742 break;
743 case 'h':
744 usage(argv[0]);
745 exit(0);
746 break;
747 case '?':
748 error_report("Try `%s --help' for more information.", argv[0]);
749 exit(EXIT_FAILURE);
750 case QEMU_NBD_OPT_OBJECT: {
751 QemuOpts *opts;
752 opts = qemu_opts_parse_noisily(&qemu_object_opts,
753 optarg, true);
754 if (!opts) {
755 exit(EXIT_FAILURE);
756 }
757 } break;
758 case QEMU_NBD_OPT_TLSCREDS:
759 tlscredsid = optarg;
760 break;
761 case QEMU_NBD_OPT_IMAGE_OPTS:
762 imageOpts = true;
763 break;
764 case 'T':
765 g_free(trace_file);
766 trace_file = trace_opt_parse(optarg);
767 break;
768 case QEMU_NBD_OPT_TLSAUTHZ:
769 tlsauthz = optarg;
770 break;
771 case QEMU_NBD_OPT_FORK:
772 fork_process = true;
773 break;
774 case 'L':
775 list = true;
776 break;
777 case QEMU_NBD_OPT_PID_FILE:
778 pid_file_name = optarg;
779 break;
780 }
781 }
782
783 if (list) {
784 if (argc != optind) {
785 error_report("List mode is incompatible with a file name");
786 exit(EXIT_FAILURE);
787 }
788 if (export_name || export_description || dev_offset ||
789 device || disconnect || fmt || sn_id_or_name || bitmap ||
790 seen_aio || seen_discard || seen_cache) {
791 error_report("List mode is incompatible with per-device settings");
792 exit(EXIT_FAILURE);
793 }
794 if (fork_process) {
795 error_report("List mode is incompatible with forking");
796 exit(EXIT_FAILURE);
797 }
798 } else if ((argc - optind) != 1) {
799 error_report("Invalid number of arguments");
800 error_printf("Try `%s --help' for more information.\n", argv[0]);
801 exit(EXIT_FAILURE);
802 } else if (!export_name) {
803 export_name = "";
804 }
805
806 qemu_opts_foreach(&qemu_object_opts,
807 user_creatable_add_opts_foreach,
808 qemu_nbd_object_print_help, &error_fatal);
809
810 if (!trace_init_backends()) {
811 exit(1);
812 }
813 trace_init_file(trace_file);
814 qemu_set_log(LOG_TRACE);
815
816 socket_activation = check_socket_activation();
817 if (socket_activation == 0) {
818 setup_address_and_port(&bindto, &port);
819 } else {
820 /* Using socket activation - check user didn't use -p etc. */
821 const char *err_msg = socket_activation_validate_opts(device, sockpath,
822 bindto, port,
823 list);
824 if (err_msg != NULL) {
825 error_report("%s", err_msg);
826 exit(EXIT_FAILURE);
827 }
828
829 /* qemu-nbd can only listen on a single socket. */
830 if (socket_activation > 1) {
831 error_report("qemu-nbd does not support socket activation with %s > 1",
832 "LISTEN_FDS");
833 exit(EXIT_FAILURE);
834 }
835 }
836
837 if (tlscredsid) {
838 if (sockpath) {
839 error_report("TLS is only supported with IPv4/IPv6");
840 exit(EXIT_FAILURE);
841 }
842 if (device) {
843 error_report("TLS is not supported with a host device");
844 exit(EXIT_FAILURE);
845 }
846 if (tlsauthz && list) {
847 error_report("TLS authorization is incompatible with export list");
848 exit(EXIT_FAILURE);
849 }
850 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
851 if (local_err) {
852 error_reportf_err(local_err, "Failed to get TLS creds: ");
853 exit(EXIT_FAILURE);
854 }
855 } else {
856 if (tlsauthz) {
857 error_report("--tls-authz is not permitted without --tls-creds");
858 exit(EXIT_FAILURE);
859 }
860 }
861
862 if (list) {
863 saddr = nbd_build_socket_address(sockpath, bindto, port);
864 return qemu_nbd_client_list(saddr, tlscreds, bindto);
865 }
866
867 #if !HAVE_NBD_DEVICE
868 if (disconnect || device) {
869 error_report("Kernel /dev/nbdN support not available");
870 exit(EXIT_FAILURE);
871 }
872 #else /* HAVE_NBD_DEVICE */
873 if (disconnect) {
874 int nbdfd = open(argv[optind], O_RDWR);
875 if (nbdfd < 0) {
876 error_report("Cannot open %s: %s", argv[optind],
877 strerror(errno));
878 exit(EXIT_FAILURE);
879 }
880 nbd_disconnect(nbdfd);
881
882 close(nbdfd);
883
884 printf("%s disconnected\n", argv[optind]);
885
886 return 0;
887 }
888 #endif
889
890 if ((device && !verbose) || fork_process) {
891 #ifndef WIN32
892 int stderr_fd[2];
893 pid_t pid;
894 int ret;
895
896 if (qemu_pipe(stderr_fd) < 0) {
897 error_report("Error setting up communication pipe: %s",
898 strerror(errno));
899 exit(EXIT_FAILURE);
900 }
901
902 /* Now daemonize, but keep a communication channel open to
903 * print errors and exit with the proper status code.
904 */
905 pid = fork();
906 if (pid < 0) {
907 error_report("Failed to fork: %s", strerror(errno));
908 exit(EXIT_FAILURE);
909 } else if (pid == 0) {
910 close(stderr_fd[0]);
911
912 /* Remember parent's stderr if we will be restoring it. */
913 if (fork_process) {
914 old_stderr = dup(STDERR_FILENO);
915 }
916
917 ret = qemu_daemon(1, 0);
918
919 /* Temporarily redirect stderr to the parent's pipe... */
920 dup2(stderr_fd[1], STDERR_FILENO);
921 if (ret < 0) {
922 error_report("Failed to daemonize: %s", strerror(errno));
923 exit(EXIT_FAILURE);
924 }
925
926 /* ... close the descriptor we inherited and go on. */
927 close(stderr_fd[1]);
928 } else {
929 bool errors = false;
930 char *buf;
931
932 /* In the parent. Print error messages from the child until
933 * it closes the pipe.
934 */
935 close(stderr_fd[1]);
936 buf = g_malloc(1024);
937 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
938 errors = true;
939 ret = qemu_write_full(STDERR_FILENO, buf, ret);
940 if (ret < 0) {
941 exit(EXIT_FAILURE);
942 }
943 }
944 if (ret < 0) {
945 error_report("Cannot read from daemon: %s",
946 strerror(errno));
947 exit(EXIT_FAILURE);
948 }
949
950 /* Usually the daemon should not print any message.
951 * Exit with zero status in that case.
952 */
953 exit(errors);
954 }
955 #else /* WIN32 */
956 error_report("Unable to fork into background on Windows hosts");
957 exit(EXIT_FAILURE);
958 #endif /* WIN32 */
959 }
960
961 if (device != NULL && sockpath == NULL) {
962 sockpath = g_malloc(128);
963 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
964 }
965
966 server = qio_net_listener_new();
967 if (socket_activation == 0) {
968 saddr = nbd_build_socket_address(sockpath, bindto, port);
969 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) {
970 object_unref(OBJECT(server));
971 error_report_err(local_err);
972 exit(EXIT_FAILURE);
973 }
974 } else {
975 size_t i;
976 /* See comment in check_socket_activation above. */
977 for (i = 0; i < socket_activation; i++) {
978 QIOChannelSocket *sioc;
979 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
980 &local_err);
981 if (sioc == NULL) {
982 object_unref(OBJECT(server));
983 error_reportf_err(local_err,
984 "Failed to use socket activation: ");
985 exit(EXIT_FAILURE);
986 }
987 qio_net_listener_add(server, sioc);
988 object_unref(OBJECT(sioc));
989 }
990 }
991
992 if (qemu_init_main_loop(&local_err)) {
993 error_report_err(local_err);
994 exit(EXIT_FAILURE);
995 }
996 bdrv_init();
997 atexit(qemu_nbd_shutdown);
998
999 srcpath = argv[optind];
1000 if (imageOpts) {
1001 QemuOpts *opts;
1002 if (fmt) {
1003 error_report("--image-opts and -f are mutually exclusive");
1004 exit(EXIT_FAILURE);
1005 }
1006 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1007 if (!opts) {
1008 qemu_opts_reset(&file_opts);
1009 exit(EXIT_FAILURE);
1010 }
1011 options = qemu_opts_to_qdict(opts, NULL);
1012 qemu_opts_reset(&file_opts);
1013 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1014 } else {
1015 if (fmt) {
1016 options = qdict_new();
1017 qdict_put_str(options, "driver", fmt);
1018 }
1019 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1020 }
1021
1022 if (!blk) {
1023 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1024 argv[optind]);
1025 exit(EXIT_FAILURE);
1026 }
1027 bs = blk_bs(blk);
1028
1029 if (dev_offset) {
1030 QDict *raw_opts = qdict_new();
1031 qdict_put_str(raw_opts, "driver", "raw");
1032 qdict_put_str(raw_opts, "file", bs->node_name);
1033 qdict_put_int(raw_opts, "offset", dev_offset);
1034 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1035 blk_remove_bs(blk);
1036 blk_insert_bs(blk, bs, &error_fatal);
1037 bdrv_unref(bs);
1038 }
1039
1040 blk_set_enable_write_cache(blk, !writethrough);
1041
1042 if (sn_opts) {
1043 ret = bdrv_snapshot_load_tmp(bs,
1044 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1045 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1046 &local_err);
1047 } else if (sn_id_or_name) {
1048 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1049 &local_err);
1050 }
1051 if (ret < 0) {
1052 error_reportf_err(local_err, "Failed to load snapshot: ");
1053 exit(EXIT_FAILURE);
1054 }
1055
1056 bs->detect_zeroes = detect_zeroes;
1057
1058 nbd_server_is_qemu_nbd(true);
1059
1060 export_opts = g_new(BlockExportOptions, 1);
1061 *export_opts = (BlockExportOptions) {
1062 .type = BLOCK_EXPORT_TYPE_NBD,
1063 .id = g_strdup("qemu-nbd-export"),
1064 .node_name = g_strdup(bdrv_get_node_name(bs)),
1065 .has_writethrough = true,
1066 .writethrough = writethrough,
1067 .has_writable = true,
1068 .writable = !readonly,
1069 .u.nbd = {
1070 .has_name = true,
1071 .name = g_strdup(export_name),
1072 .has_description = !!export_description,
1073 .description = g_strdup(export_description),
1074 .has_bitmap = !!bitmap,
1075 .bitmap = g_strdup(bitmap),
1076 },
1077 };
1078 blk_exp_add(export_opts, &error_fatal);
1079 qapi_free_BlockExportOptions(export_opts);
1080
1081 if (device) {
1082 #if HAVE_NBD_DEVICE
1083 int ret;
1084
1085 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1086 if (ret != 0) {
1087 error_report("Failed to create client thread: %s", strerror(ret));
1088 exit(EXIT_FAILURE);
1089 }
1090 #endif
1091 } else {
1092 /* Shut up GCC warnings. */
1093 memset(&client_thread, 0, sizeof(client_thread));
1094 }
1095
1096 nbd_update_server_watch();
1097
1098 if (pid_file_name) {
1099 qemu_write_pidfile(pid_file_name, &error_fatal);
1100 }
1101
1102 /* now when the initialization is (almost) complete, chdir("/")
1103 * to free any busy filesystems */
1104 if (chdir("/") < 0) {
1105 error_report("Could not chdir to root directory: %s",
1106 strerror(errno));
1107 exit(EXIT_FAILURE);
1108 }
1109
1110 if (fork_process) {
1111 dup2(old_stderr, STDERR_FILENO);
1112 close(old_stderr);
1113 }
1114
1115 state = RUNNING;
1116 do {
1117 main_loop_wait(false);
1118 if (state == TERMINATE) {
1119 blk_exp_close_all();
1120 state = TERMINATED;
1121 }
1122 } while (state != TERMINATED);
1123
1124 blk_unref(blk);
1125 if (sockpath) {
1126 unlink(sockpath);
1127 }
1128
1129 qemu_opts_del(sn_opts);
1130
1131 if (device) {
1132 void *ret;
1133 pthread_join(client_thread, &ret);
1134 exit(ret != NULL);
1135 } else {
1136 exit(EXIT_SUCCESS);
1137 }
1138 }