Merge remote-tracking branch 'remotes/cohuck-gitlab/tags/s390x-20210121' into staging
[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 " -A, --allocation-depth expose the allocation depth\n"
104 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
105 "\n"
106 "General purpose options:\n"
107 " -L, --list list exports available from another NBD server\n"
108 " --object type,id=ID,... define an object such as 'secret' for providing\n"
109 " passwords and/or encryption keys\n"
110 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
111 " --tls-authz=ID use id of an earlier --object to provide\n"
112 " authorization\n"
113 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
114 " specify tracing options\n"
115 " --fork fork off the server process and exit the parent\n"
116 " once the server is running\n"
117 " --pid-file=PATH store the server's process ID in the given file\n"
118 #if HAVE_NBD_DEVICE
119 "\n"
120 "Kernel NBD client support:\n"
121 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
122 " -d, --disconnect disconnect the specified device\n"
123 #endif
124 "\n"
125 "Block device options:\n"
126 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
127 " -r, --read-only export read-only\n"
128 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
129 " file with backing_file=FILE, redirect the write to\n"
130 " the temporary one\n"
131 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
132 " load an internal snapshot inside FILE and export it\n"
133 " as an read-only device, SNAPSHOT_PARAM format is\n"
134 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
135 " '[ID_OR_NAME]'\n"
136 " -n, --nocache disable host cache\n"
137 " --cache=MODE set cache mode (none, writeback, ...)\n"
138 " --aio=MODE set AIO mode (native, io_uring or threads)\n"
139 " --discard=MODE set discard mode (ignore, unmap)\n"
140 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
141 " --image-opts treat FILE as a full set of image options\n"
142 "\n"
143 QEMU_HELP_BOTTOM "\n"
144 , name, name, NBD_DEFAULT_PORT, "DEVICE");
145 }
146
147 static void version(const char *name)
148 {
149 printf(
150 "%s " QEMU_FULL_VERSION "\n"
151 "Written by Anthony Liguori.\n"
152 "\n"
153 QEMU_COPYRIGHT "\n"
154 "This is free software; see the source for copying conditions. There is NO\n"
155 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
156 , name);
157 }
158
159 #ifdef CONFIG_POSIX
160 /*
161 * The client thread uses SIGTERM to interrupt the server. A signal
162 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
163 */
164 void qemu_system_killed(int signum, pid_t pid)
165 {
166 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
167 qemu_notify_event();
168 }
169 #endif /* CONFIG_POSIX */
170
171 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
172 const char *hostname)
173 {
174 int ret = EXIT_FAILURE;
175 int rc;
176 Error *err = NULL;
177 QIOChannelSocket *sioc;
178 NBDExportInfo *list;
179 int i, j;
180
181 sioc = qio_channel_socket_new();
182 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
183 error_report_err(err);
184 goto out;
185 }
186 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
187 &err);
188 if (rc < 0) {
189 if (err) {
190 error_report_err(err);
191 }
192 goto out;
193 }
194 printf("exports available: %d\n", rc);
195 for (i = 0; i < rc; i++) {
196 printf(" export: '%s'\n", list[i].name);
197 if (list[i].description && *list[i].description) {
198 printf(" description: %s\n", list[i].description);
199 }
200 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
201 static const char *const flag_names[] = {
202 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
203 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
204 [NBD_FLAG_SEND_FUA_BIT] = "fua",
205 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
206 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
207 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
208 [NBD_FLAG_SEND_DF_BIT] = "df",
209 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
210 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
211 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
212 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
213 };
214
215 printf(" size: %" PRIu64 "\n", list[i].size);
216 printf(" flags: 0x%x (", list[i].flags);
217 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
218 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
219 printf(" %s", flag_names[bit]);
220 }
221 }
222 printf(" )\n");
223 }
224 if (list[i].min_block) {
225 printf(" min block: %u\n", list[i].min_block);
226 printf(" opt block: %u\n", list[i].opt_block);
227 printf(" max block: %u\n", list[i].max_block);
228 }
229 if (list[i].n_contexts) {
230 printf(" available meta contexts: %d\n", list[i].n_contexts);
231 for (j = 0; j < list[i].n_contexts; j++) {
232 printf(" %s\n", list[i].contexts[j]);
233 }
234 }
235 }
236 nbd_free_export_list(list, rc);
237
238 ret = EXIT_SUCCESS;
239 out:
240 object_unref(OBJECT(sioc));
241 return ret;
242 }
243
244
245 #if HAVE_NBD_DEVICE
246 static void *show_parts(void *arg)
247 {
248 char *device = arg;
249 int nbd;
250
251 /* linux just needs an open() to trigger
252 * the partition table update
253 * but remember to load the module with max_part != 0 :
254 * modprobe nbd max_part=63
255 */
256 nbd = open(device, O_RDWR);
257 if (nbd >= 0) {
258 close(nbd);
259 }
260 return NULL;
261 }
262
263 static void *nbd_client_thread(void *arg)
264 {
265 char *device = arg;
266 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
267 QIOChannelSocket *sioc;
268 int fd = -1;
269 int ret = EXIT_FAILURE;
270 pthread_t show_parts_thread;
271 Error *local_error = NULL;
272
273 sioc = qio_channel_socket_new();
274 if (qio_channel_socket_connect_sync(sioc,
275 saddr,
276 &local_error) < 0) {
277 error_report_err(local_error);
278 goto out;
279 }
280
281 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
282 NULL, NULL, NULL, &info, &local_error) < 0) {
283 if (local_error) {
284 error_report_err(local_error);
285 }
286 goto out;
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;
294 }
295
296 if (nbd_init(fd, sioc, &info, &local_error) < 0) {
297 error_report_err(local_error);
298 goto out;
299 }
300
301 /* update partition table */
302 pthread_create(&show_parts_thread, NULL, show_parts, device);
303
304 if (verbose) {
305 fprintf(stderr, "NBD device %s is now connected to %s\n",
306 device, srcpath);
307 } else {
308 /* Close stderr so that the qemu-nbd process exits. */
309 dup2(STDOUT_FILENO, STDERR_FILENO);
310 }
311
312 if (nbd_client(fd) < 0) {
313 goto out;
314 }
315
316 ret = EXIT_SUCCESS;
317
318 out:
319 if (fd >= 0) {
320 close(fd);
321 }
322 object_unref(OBJECT(sioc));
323 g_free(info.name);
324 kill(getpid(), SIGTERM);
325 return (void *) (intptr_t) ret;
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_update_server_watch(void);
335
336 static void nbd_client_closed(NBDClient *client, bool negotiated)
337 {
338 nb_fds--;
339 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
340 state = TERMINATE;
341 }
342 nbd_update_server_watch();
343 nbd_client_put(client);
344 }
345
346 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
347 gpointer opaque)
348 {
349 if (state >= TERMINATE) {
350 return;
351 }
352
353 nb_fds++;
354 nbd_update_server_watch();
355 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
356 }
357
358 static void nbd_update_server_watch(void)
359 {
360 if (nbd_can_accept()) {
361 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
362 } else {
363 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
364 }
365 }
366
367
368 static SocketAddress *nbd_build_socket_address(const char *sockpath,
369 const char *bindto,
370 const char *port)
371 {
372 SocketAddress *saddr;
373
374 saddr = g_new0(SocketAddress, 1);
375 if (sockpath) {
376 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
377 saddr->u.q_unix.path = g_strdup(sockpath);
378 } else {
379 InetSocketAddress *inet;
380 saddr->type = SOCKET_ADDRESS_TYPE_INET;
381 inet = &saddr->u.inet;
382 inet->host = g_strdup(bindto);
383 if (port) {
384 inet->port = g_strdup(port);
385 } else {
386 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
387 }
388 }
389
390 return saddr;
391 }
392
393
394 static QemuOptsList file_opts = {
395 .name = "file",
396 .implied_opt_name = "file",
397 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
398 .desc = {
399 /* no elements => accept any params */
400 { /* end of list */ }
401 },
402 };
403
404 static QemuOptsList qemu_object_opts = {
405 .name = "object",
406 .implied_opt_name = "qom-type",
407 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
408 .desc = {
409 { }
410 },
411 };
412
413 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
414 {
415 if (user_creatable_print_help(type, opts)) {
416 exit(0);
417 }
418 return true;
419 }
420
421
422 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
423 Error **errp)
424 {
425 Object *obj;
426 QCryptoTLSCreds *creds;
427
428 obj = object_resolve_path_component(
429 object_get_objects_root(), id);
430 if (!obj) {
431 error_setg(errp, "No TLS credentials with id '%s'",
432 id);
433 return NULL;
434 }
435 creds = (QCryptoTLSCreds *)
436 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
437 if (!creds) {
438 error_setg(errp, "Object with id '%s' is not TLS credentials",
439 id);
440 return NULL;
441 }
442
443 if (list) {
444 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
445 error_setg(errp,
446 "Expecting TLS credentials with a client endpoint");
447 return NULL;
448 }
449 } else {
450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
451 error_setg(errp,
452 "Expecting TLS credentials with a server endpoint");
453 return NULL;
454 }
455 }
456 object_ref(obj);
457 return creds;
458 }
459
460 static void setup_address_and_port(const char **address, const char **port)
461 {
462 if (*address == NULL) {
463 *address = "0.0.0.0";
464 }
465
466 if (*port == NULL) {
467 *port = stringify(NBD_DEFAULT_PORT);
468 }
469 }
470
471 /*
472 * Check socket parameters compatibility when socket activation is used.
473 */
474 static const char *socket_activation_validate_opts(const char *device,
475 const char *sockpath,
476 const char *address,
477 const char *port,
478 bool list)
479 {
480 if (device != NULL) {
481 return "NBD device can't be set when using socket activation";
482 }
483
484 if (sockpath != NULL) {
485 return "Unix socket can't be set when using socket activation";
486 }
487
488 if (address != NULL) {
489 return "The interface can't be set when using socket activation";
490 }
491
492 if (port != NULL) {
493 return "TCP port number can't be set when using socket activation";
494 }
495
496 if (list) {
497 return "List mode is incompatible with socket activation";
498 }
499
500 return NULL;
501 }
502
503 static void qemu_nbd_shutdown(void)
504 {
505 job_cancel_sync_all();
506 bdrv_close_all();
507 }
508
509 int main(int argc, char **argv)
510 {
511 BlockBackend *blk;
512 BlockDriverState *bs;
513 uint64_t dev_offset = 0;
514 bool readonly = false;
515 bool disconnect = false;
516 const char *bindto = NULL;
517 const char *port = NULL;
518 char *sockpath = NULL;
519 char *device = NULL;
520 QemuOpts *sn_opts = NULL;
521 const char *sn_id_or_name = NULL;
522 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
523 struct option lopt[] = {
524 { "help", no_argument, NULL, 'h' },
525 { "version", no_argument, NULL, 'V' },
526 { "bind", required_argument, NULL, 'b' },
527 { "port", required_argument, NULL, 'p' },
528 { "socket", required_argument, NULL, 'k' },
529 { "offset", required_argument, NULL, 'o' },
530 { "read-only", no_argument, NULL, 'r' },
531 { "allocation-depth", no_argument, NULL, 'A' },
532 { "bitmap", required_argument, NULL, 'B' },
533 { "connect", required_argument, NULL, 'c' },
534 { "disconnect", no_argument, NULL, 'd' },
535 { "list", no_argument, NULL, 'L' },
536 { "snapshot", no_argument, NULL, 's' },
537 { "load-snapshot", required_argument, NULL, 'l' },
538 { "nocache", no_argument, NULL, 'n' },
539 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
540 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
541 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
542 { "detect-zeroes", required_argument, NULL,
543 QEMU_NBD_OPT_DETECT_ZEROES },
544 { "shared", required_argument, NULL, 'e' },
545 { "format", required_argument, NULL, 'f' },
546 { "persistent", no_argument, NULL, 't' },
547 { "verbose", no_argument, NULL, 'v' },
548 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
549 { "export-name", required_argument, NULL, 'x' },
550 { "description", required_argument, NULL, 'D' },
551 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
552 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
553 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
554 { "trace", required_argument, NULL, 'T' },
555 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
556 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
557 { NULL, 0, NULL, 0 }
558 };
559 int ch;
560 int opt_ind = 0;
561 int flags = BDRV_O_RDWR;
562 int ret = 0;
563 bool seen_cache = false;
564 bool seen_discard = false;
565 bool seen_aio = false;
566 pthread_t client_thread;
567 const char *fmt = NULL;
568 Error *local_err = NULL;
569 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
570 QDict *options = NULL;
571 const char *export_name = NULL; /* defaults to "" later for server mode */
572 const char *export_description = NULL;
573 strList *bitmaps = NULL;
574 bool alloc_depth = false;
575 const char *tlscredsid = NULL;
576 bool imageOpts = false;
577 bool writethrough = true;
578 bool fork_process = false;
579 bool list = false;
580 int old_stderr = -1;
581 unsigned socket_activation;
582 const char *pid_file_name = NULL;
583 BlockExportOptions *export_opts;
584
585 #ifdef CONFIG_POSIX
586 os_setup_early_signal_handling();
587 os_setup_signal_handling();
588 #endif
589
590 socket_init();
591 error_init(argv[0]);
592 module_call_init(MODULE_INIT_TRACE);
593 qcrypto_init(&error_fatal);
594
595 module_call_init(MODULE_INIT_QOM);
596 qemu_add_opts(&qemu_object_opts);
597 qemu_add_opts(&qemu_trace_opts);
598 qemu_init_exec_dir(argv[0]);
599
600 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
601 switch (ch) {
602 case 's':
603 flags |= BDRV_O_SNAPSHOT;
604 break;
605 case 'n':
606 optarg = (char *) "none";
607 /* fallthrough */
608 case QEMU_NBD_OPT_CACHE:
609 if (seen_cache) {
610 error_report("-n and --cache can only be specified once");
611 exit(EXIT_FAILURE);
612 }
613 seen_cache = true;
614 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
615 error_report("Invalid cache mode `%s'", optarg);
616 exit(EXIT_FAILURE);
617 }
618 break;
619 case QEMU_NBD_OPT_AIO:
620 if (seen_aio) {
621 error_report("--aio can only be specified once");
622 exit(EXIT_FAILURE);
623 }
624 seen_aio = true;
625 if (bdrv_parse_aio(optarg, &flags) < 0) {
626 error_report("Invalid aio mode '%s'", optarg);
627 exit(EXIT_FAILURE);
628 }
629 break;
630 case QEMU_NBD_OPT_DISCARD:
631 if (seen_discard) {
632 error_report("--discard can only be specified once");
633 exit(EXIT_FAILURE);
634 }
635 seen_discard = true;
636 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
637 error_report("Invalid discard mode `%s'", optarg);
638 exit(EXIT_FAILURE);
639 }
640 break;
641 case QEMU_NBD_OPT_DETECT_ZEROES:
642 detect_zeroes =
643 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
644 optarg,
645 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
646 &local_err);
647 if (local_err) {
648 error_reportf_err(local_err,
649 "Failed to parse detect_zeroes mode: ");
650 exit(EXIT_FAILURE);
651 }
652 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
653 !(flags & BDRV_O_UNMAP)) {
654 error_report("setting detect-zeroes to unmap is not allowed "
655 "without setting discard operation to unmap");
656 exit(EXIT_FAILURE);
657 }
658 break;
659 case 'b':
660 bindto = optarg;
661 break;
662 case 'p':
663 port = optarg;
664 break;
665 case 'o':
666 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
667 error_report("Invalid offset '%s'", optarg);
668 exit(EXIT_FAILURE);
669 }
670 break;
671 case 'l':
672 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
673 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
674 optarg, false);
675 if (!sn_opts) {
676 error_report("Failed in parsing snapshot param `%s'",
677 optarg);
678 exit(EXIT_FAILURE);
679 }
680 } else {
681 sn_id_or_name = optarg;
682 }
683 /* fall through */
684 case 'r':
685 readonly = true;
686 flags &= ~BDRV_O_RDWR;
687 break;
688 case 'A':
689 alloc_depth = true;
690 break;
691 case 'B':
692 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg));
693 break;
694 case 'k':
695 sockpath = optarg;
696 if (sockpath[0] != '/') {
697 error_report("socket path must be absolute");
698 exit(EXIT_FAILURE);
699 }
700 break;
701 case 'd':
702 disconnect = true;
703 break;
704 case 'c':
705 device = optarg;
706 break;
707 case 'e':
708 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
709 shared < 1) {
710 error_report("Invalid shared device number '%s'", optarg);
711 exit(EXIT_FAILURE);
712 }
713 break;
714 case 'f':
715 fmt = optarg;
716 break;
717 case 't':
718 persistent = 1;
719 break;
720 case 'x':
721 export_name = optarg;
722 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
723 error_report("export name '%s' too long", export_name);
724 exit(EXIT_FAILURE);
725 }
726 break;
727 case 'D':
728 export_description = optarg;
729 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
730 error_report("export description '%s' too long",
731 export_description);
732 exit(EXIT_FAILURE);
733 }
734 break;
735 case 'v':
736 verbose = 1;
737 break;
738 case 'V':
739 version(argv[0]);
740 exit(0);
741 break;
742 case 'h':
743 usage(argv[0]);
744 exit(0);
745 break;
746 case '?':
747 error_report("Try `%s --help' for more information.", argv[0]);
748 exit(EXIT_FAILURE);
749 case QEMU_NBD_OPT_OBJECT: {
750 QemuOpts *opts;
751 opts = qemu_opts_parse_noisily(&qemu_object_opts,
752 optarg, true);
753 if (!opts) {
754 exit(EXIT_FAILURE);
755 }
756 } break;
757 case QEMU_NBD_OPT_TLSCREDS:
758 tlscredsid = optarg;
759 break;
760 case QEMU_NBD_OPT_IMAGE_OPTS:
761 imageOpts = true;
762 break;
763 case 'T':
764 trace_opt_parse(optarg);
765 break;
766 case QEMU_NBD_OPT_TLSAUTHZ:
767 tlsauthz = optarg;
768 break;
769 case QEMU_NBD_OPT_FORK:
770 fork_process = true;
771 break;
772 case 'L':
773 list = true;
774 break;
775 case QEMU_NBD_OPT_PID_FILE:
776 pid_file_name = optarg;
777 break;
778 }
779 }
780
781 if (list) {
782 if (argc != optind) {
783 error_report("List mode is incompatible with a file name");
784 exit(EXIT_FAILURE);
785 }
786 if (export_name || export_description || dev_offset ||
787 device || disconnect || fmt || sn_id_or_name || bitmaps ||
788 alloc_depth || seen_aio || seen_discard || seen_cache) {
789 error_report("List mode is incompatible with per-device settings");
790 exit(EXIT_FAILURE);
791 }
792 if (fork_process) {
793 error_report("List mode is incompatible with forking");
794 exit(EXIT_FAILURE);
795 }
796 } else if ((argc - optind) != 1) {
797 error_report("Invalid number of arguments");
798 error_printf("Try `%s --help' for more information.\n", argv[0]);
799 exit(EXIT_FAILURE);
800 } else if (!export_name) {
801 export_name = "";
802 }
803
804 qemu_opts_foreach(&qemu_object_opts,
805 user_creatable_add_opts_foreach,
806 qemu_nbd_object_print_help, &error_fatal);
807
808 if (!trace_init_backends()) {
809 exit(1);
810 }
811 trace_init_file();
812 qemu_set_log(LOG_TRACE);
813
814 socket_activation = check_socket_activation();
815 if (socket_activation == 0) {
816 setup_address_and_port(&bindto, &port);
817 } else {
818 /* Using socket activation - check user didn't use -p etc. */
819 const char *err_msg = socket_activation_validate_opts(device, sockpath,
820 bindto, port,
821 list);
822 if (err_msg != NULL) {
823 error_report("%s", err_msg);
824 exit(EXIT_FAILURE);
825 }
826
827 /* qemu-nbd can only listen on a single socket. */
828 if (socket_activation > 1) {
829 error_report("qemu-nbd does not support socket activation with %s > 1",
830 "LISTEN_FDS");
831 exit(EXIT_FAILURE);
832 }
833 }
834
835 if (tlscredsid) {
836 if (sockpath) {
837 error_report("TLS is only supported with IPv4/IPv6");
838 exit(EXIT_FAILURE);
839 }
840 if (device) {
841 error_report("TLS is not supported with a host device");
842 exit(EXIT_FAILURE);
843 }
844 if (tlsauthz && list) {
845 error_report("TLS authorization is incompatible with export list");
846 exit(EXIT_FAILURE);
847 }
848 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
849 if (local_err) {
850 error_reportf_err(local_err, "Failed to get TLS creds: ");
851 exit(EXIT_FAILURE);
852 }
853 } else {
854 if (tlsauthz) {
855 error_report("--tls-authz is not permitted without --tls-creds");
856 exit(EXIT_FAILURE);
857 }
858 }
859
860 if (list) {
861 saddr = nbd_build_socket_address(sockpath, bindto, port);
862 return qemu_nbd_client_list(saddr, tlscreds, bindto);
863 }
864
865 #if !HAVE_NBD_DEVICE
866 if (disconnect || device) {
867 error_report("Kernel /dev/nbdN support not available");
868 exit(EXIT_FAILURE);
869 }
870 #else /* HAVE_NBD_DEVICE */
871 if (disconnect) {
872 int nbdfd = open(argv[optind], O_RDWR);
873 if (nbdfd < 0) {
874 error_report("Cannot open %s: %s", argv[optind],
875 strerror(errno));
876 exit(EXIT_FAILURE);
877 }
878 nbd_disconnect(nbdfd);
879
880 close(nbdfd);
881
882 printf("%s disconnected\n", argv[optind]);
883
884 return 0;
885 }
886 #endif
887
888 if ((device && !verbose) || fork_process) {
889 #ifndef WIN32
890 int stderr_fd[2];
891 pid_t pid;
892 int ret;
893
894 if (qemu_pipe(stderr_fd) < 0) {
895 error_report("Error setting up communication pipe: %s",
896 strerror(errno));
897 exit(EXIT_FAILURE);
898 }
899
900 /* Now daemonize, but keep a communication channel open to
901 * print errors and exit with the proper status code.
902 */
903 pid = fork();
904 if (pid < 0) {
905 error_report("Failed to fork: %s", strerror(errno));
906 exit(EXIT_FAILURE);
907 } else if (pid == 0) {
908 close(stderr_fd[0]);
909
910 /* Remember parent's stderr if we will be restoring it. */
911 if (fork_process) {
912 old_stderr = dup(STDERR_FILENO);
913 }
914
915 ret = qemu_daemon(1, 0);
916
917 /* Temporarily redirect stderr to the parent's pipe... */
918 dup2(stderr_fd[1], STDERR_FILENO);
919 if (ret < 0) {
920 error_report("Failed to daemonize: %s", strerror(errno));
921 exit(EXIT_FAILURE);
922 }
923
924 /* ... close the descriptor we inherited and go on. */
925 close(stderr_fd[1]);
926 } else {
927 bool errors = false;
928 char *buf;
929
930 /* In the parent. Print error messages from the child until
931 * it closes the pipe.
932 */
933 close(stderr_fd[1]);
934 buf = g_malloc(1024);
935 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
936 errors = true;
937 ret = qemu_write_full(STDERR_FILENO, buf, ret);
938 if (ret < 0) {
939 exit(EXIT_FAILURE);
940 }
941 }
942 if (ret < 0) {
943 error_report("Cannot read from daemon: %s",
944 strerror(errno));
945 exit(EXIT_FAILURE);
946 }
947
948 /* Usually the daemon should not print any message.
949 * Exit with zero status in that case.
950 */
951 exit(errors);
952 }
953 #else /* WIN32 */
954 error_report("Unable to fork into background on Windows hosts");
955 exit(EXIT_FAILURE);
956 #endif /* WIN32 */
957 }
958
959 if (device != NULL && sockpath == NULL) {
960 sockpath = g_malloc(128);
961 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
962 }
963
964 server = qio_net_listener_new();
965 if (socket_activation == 0) {
966 saddr = nbd_build_socket_address(sockpath, bindto, port);
967 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) {
968 object_unref(OBJECT(server));
969 error_report_err(local_err);
970 exit(EXIT_FAILURE);
971 }
972 } else {
973 size_t i;
974 /* See comment in check_socket_activation above. */
975 for (i = 0; i < socket_activation; i++) {
976 QIOChannelSocket *sioc;
977 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
978 &local_err);
979 if (sioc == NULL) {
980 object_unref(OBJECT(server));
981 error_reportf_err(local_err,
982 "Failed to use socket activation: ");
983 exit(EXIT_FAILURE);
984 }
985 qio_net_listener_add(server, sioc);
986 object_unref(OBJECT(sioc));
987 }
988 }
989
990 if (qemu_init_main_loop(&local_err)) {
991 error_report_err(local_err);
992 exit(EXIT_FAILURE);
993 }
994 bdrv_init();
995 atexit(qemu_nbd_shutdown);
996
997 srcpath = argv[optind];
998 if (imageOpts) {
999 QemuOpts *opts;
1000 if (fmt) {
1001 error_report("--image-opts and -f are mutually exclusive");
1002 exit(EXIT_FAILURE);
1003 }
1004 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1005 if (!opts) {
1006 qemu_opts_reset(&file_opts);
1007 exit(EXIT_FAILURE);
1008 }
1009 options = qemu_opts_to_qdict(opts, NULL);
1010 qemu_opts_reset(&file_opts);
1011 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1012 } else {
1013 if (fmt) {
1014 options = qdict_new();
1015 qdict_put_str(options, "driver", fmt);
1016 }
1017 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1018 }
1019
1020 if (!blk) {
1021 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1022 argv[optind]);
1023 exit(EXIT_FAILURE);
1024 }
1025 bs = blk_bs(blk);
1026
1027 if (dev_offset) {
1028 QDict *raw_opts = qdict_new();
1029 qdict_put_str(raw_opts, "driver", "raw");
1030 qdict_put_str(raw_opts, "file", bs->node_name);
1031 qdict_put_int(raw_opts, "offset", dev_offset);
1032 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1033 blk_remove_bs(blk);
1034 blk_insert_bs(blk, bs, &error_fatal);
1035 bdrv_unref(bs);
1036 }
1037
1038 blk_set_enable_write_cache(blk, !writethrough);
1039
1040 if (sn_opts) {
1041 ret = bdrv_snapshot_load_tmp(bs,
1042 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1043 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1044 &local_err);
1045 } else if (sn_id_or_name) {
1046 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1047 &local_err);
1048 }
1049 if (ret < 0) {
1050 error_reportf_err(local_err, "Failed to load snapshot: ");
1051 exit(EXIT_FAILURE);
1052 }
1053
1054 bs->detect_zeroes = detect_zeroes;
1055
1056 nbd_server_is_qemu_nbd(true);
1057
1058 export_opts = g_new(BlockExportOptions, 1);
1059 *export_opts = (BlockExportOptions) {
1060 .type = BLOCK_EXPORT_TYPE_NBD,
1061 .id = g_strdup("qemu-nbd-export"),
1062 .node_name = g_strdup(bdrv_get_node_name(bs)),
1063 .has_writethrough = true,
1064 .writethrough = writethrough,
1065 .has_writable = true,
1066 .writable = !readonly,
1067 .u.nbd = {
1068 .has_name = true,
1069 .name = g_strdup(export_name),
1070 .has_description = !!export_description,
1071 .description = g_strdup(export_description),
1072 .has_bitmaps = !!bitmaps,
1073 .bitmaps = bitmaps,
1074 .has_allocation_depth = alloc_depth,
1075 .allocation_depth = alloc_depth,
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 }