Merge tag 'artist-cursor-fix-final-pull-request' of https://github.com/hdeller/qemu...
[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 "crypto/tlscreds.h"
47 #include "trace/control.h"
48 #include "qemu-version.h"
49
50 #ifdef CONFIG_SELINUX
51 #include <selinux/selinux.h>
52 #endif
53
54 #ifdef __linux__
55 #define HAVE_NBD_DEVICE 1
56 #else
57 #define HAVE_NBD_DEVICE 0
58 #endif
59
60 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
61 #define QEMU_NBD_OPT_CACHE 256
62 #define QEMU_NBD_OPT_AIO 257
63 #define QEMU_NBD_OPT_DISCARD 258
64 #define QEMU_NBD_OPT_DETECT_ZEROES 259
65 #define QEMU_NBD_OPT_OBJECT 260
66 #define QEMU_NBD_OPT_TLSCREDS 261
67 #define QEMU_NBD_OPT_IMAGE_OPTS 262
68 #define QEMU_NBD_OPT_FORK 263
69 #define QEMU_NBD_OPT_TLSAUTHZ 264
70 #define QEMU_NBD_OPT_PID_FILE 265
71 #define QEMU_NBD_OPT_SELINUX_LABEL 266
72
73 #define MBR_SIZE 512
74
75 static int verbose;
76 static char *srcpath;
77 static SocketAddress *saddr;
78 static int persistent = 0;
79 static enum { RUNNING, TERMINATE, TERMINATED } state;
80 static int shared = 1;
81 static int nb_fds;
82 static QIONetListener *server;
83 static QCryptoTLSCreds *tlscreds;
84 static const char *tlsauthz;
85
86 static void usage(const char *name)
87 {
88 (printf) (
89 "Usage: %s [OPTIONS] FILE\n"
90 " or: %s -L [OPTIONS]\n"
91 "QEMU Disk Network Block Device Utility\n"
92 "\n"
93 " -h, --help display this help and exit\n"
94 " -V, --version output version information and exit\n"
95 "\n"
96 "Connection properties:\n"
97 " -p, --port=PORT port to listen on (default `%d')\n"
98 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
99 " -k, --socket=PATH path to the unix socket\n"
100 " (default '"SOCKET_PATH"')\n"
101 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
102 " -t, --persistent don't exit on the last connection\n"
103 " -v, --verbose display extra debugging information\n"
104 " -x, --export-name=NAME expose export by name (default is empty string)\n"
105 " -D, --description=TEXT export a human-readable description\n"
106 "\n"
107 "Exposing part of the image:\n"
108 " -o, --offset=OFFSET offset into the image\n"
109 " -A, --allocation-depth expose the allocation depth\n"
110 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
111 "\n"
112 "General purpose options:\n"
113 " -L, --list list exports available from another NBD server\n"
114 " --object type,id=ID,... define an object such as 'secret' for providing\n"
115 " passwords and/or encryption keys\n"
116 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
117 " --tls-authz=ID use id of an earlier --object to provide\n"
118 " authorization\n"
119 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
120 " specify tracing options\n"
121 " --fork fork off the server process and exit the parent\n"
122 " once the server is running\n"
123 " --pid-file=PATH store the server's process ID in the given file\n"
124 #ifdef CONFIG_SELINUX
125 " --selinux-label=LABEL set SELinux process label on listening socket\n"
126 #endif
127 #if HAVE_NBD_DEVICE
128 "\n"
129 "Kernel NBD client support:\n"
130 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
131 " -d, --disconnect disconnect the specified device\n"
132 #endif
133 "\n"
134 "Block device options:\n"
135 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
136 " -r, --read-only export read-only\n"
137 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
138 " file with backing_file=FILE, redirect the write to\n"
139 " the temporary one\n"
140 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
141 " load an internal snapshot inside FILE and export it\n"
142 " as an read-only device, SNAPSHOT_PARAM format is\n"
143 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
144 " '[ID_OR_NAME]'\n"
145 " -n, --nocache disable host cache\n"
146 " --cache=MODE set cache mode used to access the disk image, the\n"
147 " valid options are: 'none', 'writeback' (default),\n"
148 " 'writethrough', 'directsync' and 'unsafe'\n"
149 " --aio=MODE set AIO mode (native, io_uring or threads)\n"
150 " --discard=MODE set discard mode (ignore, unmap)\n"
151 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
152 " --image-opts treat FILE as a full set of image options\n"
153 "\n"
154 QEMU_HELP_BOTTOM "\n"
155 , name, name, NBD_DEFAULT_PORT, "DEVICE");
156 }
157
158 static void version(const char *name)
159 {
160 printf(
161 "%s " QEMU_FULL_VERSION "\n"
162 "Written by Anthony Liguori.\n"
163 "\n"
164 QEMU_COPYRIGHT "\n"
165 "This is free software; see the source for copying conditions. There is NO\n"
166 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
167 , name);
168 }
169
170 #ifdef CONFIG_POSIX
171 /*
172 * The client thread uses SIGTERM to interrupt the server. A signal
173 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
174 */
175 void qemu_system_killed(int signum, pid_t pid)
176 {
177 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
178 qemu_notify_event();
179 }
180 #endif /* CONFIG_POSIX */
181
182 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
183 const char *hostname)
184 {
185 int ret = EXIT_FAILURE;
186 int rc;
187 Error *err = NULL;
188 QIOChannelSocket *sioc;
189 NBDExportInfo *list;
190 int i, j;
191
192 sioc = qio_channel_socket_new();
193 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
194 error_report_err(err);
195 goto out;
196 }
197 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
198 &err);
199 if (rc < 0) {
200 if (err) {
201 error_report_err(err);
202 }
203 goto out;
204 }
205 printf("exports available: %d\n", rc);
206 for (i = 0; i < rc; i++) {
207 printf(" export: '%s'\n", list[i].name);
208 if (list[i].description && *list[i].description) {
209 printf(" description: %s\n", list[i].description);
210 }
211 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
212 static const char *const flag_names[] = {
213 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
214 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
215 [NBD_FLAG_SEND_FUA_BIT] = "fua",
216 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
217 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
218 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
219 [NBD_FLAG_SEND_DF_BIT] = "df",
220 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
221 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
222 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
223 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero",
224 };
225
226 printf(" size: %" PRIu64 "\n", list[i].size);
227 printf(" flags: 0x%x (", list[i].flags);
228 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
229 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
230 printf(" %s", flag_names[bit]);
231 }
232 }
233 printf(" )\n");
234 }
235 if (list[i].min_block) {
236 printf(" min block: %u\n", list[i].min_block);
237 printf(" opt block: %u\n", list[i].opt_block);
238 printf(" max block: %u\n", list[i].max_block);
239 }
240 if (list[i].n_contexts) {
241 printf(" available meta contexts: %d\n", list[i].n_contexts);
242 for (j = 0; j < list[i].n_contexts; j++) {
243 printf(" %s\n", list[i].contexts[j]);
244 }
245 }
246 }
247 nbd_free_export_list(list, rc);
248
249 ret = EXIT_SUCCESS;
250 out:
251 object_unref(OBJECT(sioc));
252 return ret;
253 }
254
255
256 #if HAVE_NBD_DEVICE
257 static void *show_parts(void *arg)
258 {
259 char *device = arg;
260 int nbd;
261
262 /* linux just needs an open() to trigger
263 * the partition table update
264 * but remember to load the module with max_part != 0 :
265 * modprobe nbd max_part=63
266 */
267 nbd = open(device, O_RDWR);
268 if (nbd >= 0) {
269 close(nbd);
270 }
271 return NULL;
272 }
273
274 static void *nbd_client_thread(void *arg)
275 {
276 char *device = arg;
277 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
278 QIOChannelSocket *sioc;
279 int fd = -1;
280 int ret = EXIT_FAILURE;
281 pthread_t show_parts_thread;
282 Error *local_error = NULL;
283
284 sioc = qio_channel_socket_new();
285 if (qio_channel_socket_connect_sync(sioc,
286 saddr,
287 &local_error) < 0) {
288 error_report_err(local_error);
289 goto out;
290 }
291
292 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
293 NULL, NULL, NULL, &info, &local_error) < 0) {
294 if (local_error) {
295 error_report_err(local_error);
296 }
297 goto out;
298 }
299
300 fd = open(device, O_RDWR);
301 if (fd < 0) {
302 /* Linux-only, we can use %m in printf. */
303 error_report("Failed to open %s: %m", device);
304 goto out;
305 }
306
307 if (nbd_init(fd, sioc, &info, &local_error) < 0) {
308 error_report_err(local_error);
309 goto out;
310 }
311
312 /* update partition table */
313 pthread_create(&show_parts_thread, NULL, show_parts, device);
314
315 if (verbose) {
316 fprintf(stderr, "NBD device %s is now connected to %s\n",
317 device, srcpath);
318 } else {
319 /* Close stderr so that the qemu-nbd process exits. */
320 dup2(STDOUT_FILENO, STDERR_FILENO);
321 }
322
323 if (nbd_client(fd) < 0) {
324 goto out;
325 }
326
327 ret = EXIT_SUCCESS;
328
329 out:
330 if (fd >= 0) {
331 close(fd);
332 }
333 object_unref(OBJECT(sioc));
334 g_free(info.name);
335 kill(getpid(), SIGTERM);
336 return (void *) (intptr_t) ret;
337 }
338 #endif /* HAVE_NBD_DEVICE */
339
340 static int nbd_can_accept(void)
341 {
342 return state == RUNNING && (shared == 0 || nb_fds < shared);
343 }
344
345 static void nbd_update_server_watch(void);
346
347 static void nbd_client_closed(NBDClient *client, bool negotiated)
348 {
349 nb_fds--;
350 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
351 state = TERMINATE;
352 }
353 nbd_update_server_watch();
354 nbd_client_put(client);
355 }
356
357 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
358 gpointer opaque)
359 {
360 if (state >= TERMINATE) {
361 return;
362 }
363
364 nb_fds++;
365 nbd_update_server_watch();
366 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
367 }
368
369 static void nbd_update_server_watch(void)
370 {
371 if (nbd_can_accept()) {
372 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
373 } else {
374 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
375 }
376 }
377
378
379 static SocketAddress *nbd_build_socket_address(const char *sockpath,
380 const char *bindto,
381 const char *port)
382 {
383 SocketAddress *saddr;
384
385 saddr = g_new0(SocketAddress, 1);
386 if (sockpath) {
387 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
388 saddr->u.q_unix.path = g_strdup(sockpath);
389 } else {
390 InetSocketAddress *inet;
391 saddr->type = SOCKET_ADDRESS_TYPE_INET;
392 inet = &saddr->u.inet;
393 inet->host = g_strdup(bindto);
394 if (port) {
395 inet->port = g_strdup(port);
396 } else {
397 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
398 }
399 }
400
401 return saddr;
402 }
403
404
405 static QemuOptsList file_opts = {
406 .name = "file",
407 .implied_opt_name = "file",
408 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
409 .desc = {
410 /* no elements => accept any params */
411 { /* end of list */ }
412 },
413 };
414
415 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
416 Error **errp)
417 {
418 Object *obj;
419 QCryptoTLSCreds *creds;
420
421 obj = object_resolve_path_component(
422 object_get_objects_root(), id);
423 if (!obj) {
424 error_setg(errp, "No TLS credentials with id '%s'",
425 id);
426 return NULL;
427 }
428 creds = (QCryptoTLSCreds *)
429 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
430 if (!creds) {
431 error_setg(errp, "Object with id '%s' is not TLS credentials",
432 id);
433 return NULL;
434 }
435
436 if (!qcrypto_tls_creds_check_endpoint(creds,
437 list
438 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT
439 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
440 errp)) {
441 return NULL;
442 }
443 object_ref(obj);
444 return creds;
445 }
446
447 static void setup_address_and_port(const char **address, const char **port)
448 {
449 if (*address == NULL) {
450 *address = "0.0.0.0";
451 }
452
453 if (*port == NULL) {
454 *port = stringify(NBD_DEFAULT_PORT);
455 }
456 }
457
458 /*
459 * Check socket parameters compatibility when socket activation is used.
460 */
461 static const char *socket_activation_validate_opts(const char *device,
462 const char *sockpath,
463 const char *address,
464 const char *port,
465 const char *selinux,
466 bool list)
467 {
468 if (device != NULL) {
469 return "NBD device can't be set when using socket activation";
470 }
471
472 if (sockpath != NULL) {
473 return "Unix socket can't be set when using socket activation";
474 }
475
476 if (address != NULL) {
477 return "The interface can't be set when using socket activation";
478 }
479
480 if (port != NULL) {
481 return "TCP port number can't be set when using socket activation";
482 }
483
484 if (selinux != NULL) {
485 return "SELinux label can't be set when using socket activation";
486 }
487
488 if (list) {
489 return "List mode is incompatible with socket activation";
490 }
491
492 return NULL;
493 }
494
495 static void qemu_nbd_shutdown(void)
496 {
497 job_cancel_sync_all();
498 blk_exp_close_all();
499 bdrv_close_all();
500 }
501
502 int main(int argc, char **argv)
503 {
504 BlockBackend *blk;
505 BlockDriverState *bs;
506 uint64_t dev_offset = 0;
507 bool readonly = false;
508 bool disconnect = false;
509 const char *bindto = NULL;
510 const char *port = NULL;
511 char *sockpath = NULL;
512 char *device = NULL;
513 QemuOpts *sn_opts = NULL;
514 const char *sn_id_or_name = NULL;
515 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
516 struct option lopt[] = {
517 { "help", no_argument, NULL, 'h' },
518 { "version", no_argument, NULL, 'V' },
519 { "bind", required_argument, NULL, 'b' },
520 { "port", required_argument, NULL, 'p' },
521 { "socket", required_argument, NULL, 'k' },
522 { "offset", required_argument, NULL, 'o' },
523 { "read-only", no_argument, NULL, 'r' },
524 { "allocation-depth", no_argument, NULL, 'A' },
525 { "bitmap", required_argument, NULL, 'B' },
526 { "connect", required_argument, NULL, 'c' },
527 { "disconnect", no_argument, NULL, 'd' },
528 { "list", no_argument, NULL, 'L' },
529 { "snapshot", no_argument, NULL, 's' },
530 { "load-snapshot", required_argument, NULL, 'l' },
531 { "nocache", no_argument, NULL, 'n' },
532 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
533 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
534 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
535 { "detect-zeroes", required_argument, NULL,
536 QEMU_NBD_OPT_DETECT_ZEROES },
537 { "shared", required_argument, NULL, 'e' },
538 { "format", required_argument, NULL, 'f' },
539 { "persistent", no_argument, NULL, 't' },
540 { "verbose", no_argument, NULL, 'v' },
541 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
542 { "export-name", required_argument, NULL, 'x' },
543 { "description", required_argument, NULL, 'D' },
544 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
545 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
546 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
547 { "trace", required_argument, NULL, 'T' },
548 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
549 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
550 { "selinux-label", required_argument, NULL,
551 QEMU_NBD_OPT_SELINUX_LABEL },
552 { NULL, 0, NULL, 0 }
553 };
554 int ch;
555 int opt_ind = 0;
556 int flags = BDRV_O_RDWR;
557 int ret = 0;
558 bool seen_cache = false;
559 bool seen_discard = false;
560 bool seen_aio = false;
561 pthread_t client_thread;
562 const char *fmt = NULL;
563 Error *local_err = NULL;
564 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
565 QDict *options = NULL;
566 const char *export_name = NULL; /* defaults to "" later for server mode */
567 const char *export_description = NULL;
568 strList *bitmaps = NULL;
569 bool alloc_depth = false;
570 const char *tlscredsid = NULL;
571 bool imageOpts = false;
572 bool writethrough = false; /* Client will flush as needed. */
573 bool fork_process = false;
574 bool list = false;
575 int old_stderr = -1;
576 unsigned socket_activation;
577 const char *pid_file_name = NULL;
578 const char *selinux_label = NULL;
579 BlockExportOptions *export_opts;
580
581 #ifdef CONFIG_POSIX
582 os_setup_early_signal_handling();
583 os_setup_signal_handling();
584 #endif
585
586 socket_init();
587 error_init(argv[0]);
588 module_call_init(MODULE_INIT_TRACE);
589 qcrypto_init(&error_fatal);
590
591 module_call_init(MODULE_INIT_QOM);
592 qemu_add_opts(&qemu_trace_opts);
593 qemu_init_exec_dir(argv[0]);
594
595 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
596 switch (ch) {
597 case 's':
598 flags |= BDRV_O_SNAPSHOT;
599 break;
600 case 'n':
601 optarg = (char *) "none";
602 /* fallthrough */
603 case QEMU_NBD_OPT_CACHE:
604 if (seen_cache) {
605 error_report("-n and --cache can only be specified once");
606 exit(EXIT_FAILURE);
607 }
608 seen_cache = true;
609 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
610 error_report("Invalid cache mode `%s'", optarg);
611 exit(EXIT_FAILURE);
612 }
613 break;
614 case QEMU_NBD_OPT_AIO:
615 if (seen_aio) {
616 error_report("--aio can only be specified once");
617 exit(EXIT_FAILURE);
618 }
619 seen_aio = true;
620 if (bdrv_parse_aio(optarg, &flags) < 0) {
621 error_report("Invalid aio mode '%s'", optarg);
622 exit(EXIT_FAILURE);
623 }
624 break;
625 case QEMU_NBD_OPT_DISCARD:
626 if (seen_discard) {
627 error_report("--discard can only be specified once");
628 exit(EXIT_FAILURE);
629 }
630 seen_discard = true;
631 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
632 error_report("Invalid discard mode `%s'", optarg);
633 exit(EXIT_FAILURE);
634 }
635 break;
636 case QEMU_NBD_OPT_DETECT_ZEROES:
637 detect_zeroes =
638 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
639 optarg,
640 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
641 &local_err);
642 if (local_err) {
643 error_reportf_err(local_err,
644 "Failed to parse detect_zeroes mode: ");
645 exit(EXIT_FAILURE);
646 }
647 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
648 !(flags & BDRV_O_UNMAP)) {
649 error_report("setting detect-zeroes to unmap is not allowed "
650 "without setting discard operation to unmap");
651 exit(EXIT_FAILURE);
652 }
653 break;
654 case 'b':
655 bindto = optarg;
656 break;
657 case 'p':
658 port = optarg;
659 break;
660 case 'o':
661 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
662 error_report("Invalid offset '%s'", optarg);
663 exit(EXIT_FAILURE);
664 }
665 break;
666 case 'l':
667 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
668 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
669 optarg, false);
670 if (!sn_opts) {
671 error_report("Failed in parsing snapshot param `%s'",
672 optarg);
673 exit(EXIT_FAILURE);
674 }
675 } else {
676 sn_id_or_name = optarg;
677 }
678 /* fall through */
679 case 'r':
680 readonly = true;
681 flags &= ~BDRV_O_RDWR;
682 break;
683 case 'A':
684 alloc_depth = true;
685 break;
686 case 'B':
687 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg));
688 break;
689 case 'k':
690 sockpath = optarg;
691 if (sockpath[0] != '/') {
692 error_report("socket path must be absolute");
693 exit(EXIT_FAILURE);
694 }
695 break;
696 case 'd':
697 disconnect = true;
698 break;
699 case 'c':
700 device = optarg;
701 break;
702 case 'e':
703 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
704 shared < 0) {
705 error_report("Invalid shared device number '%s'", optarg);
706 exit(EXIT_FAILURE);
707 }
708 break;
709 case 'f':
710 fmt = optarg;
711 break;
712 case 't':
713 persistent = 1;
714 break;
715 case 'x':
716 export_name = optarg;
717 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
718 error_report("export name '%s' too long", export_name);
719 exit(EXIT_FAILURE);
720 }
721 break;
722 case 'D':
723 export_description = optarg;
724 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
725 error_report("export description '%s' too long",
726 export_description);
727 exit(EXIT_FAILURE);
728 }
729 break;
730 case 'v':
731 verbose = 1;
732 break;
733 case 'V':
734 version(argv[0]);
735 exit(0);
736 break;
737 case 'h':
738 usage(argv[0]);
739 exit(0);
740 break;
741 case '?':
742 error_report("Try `%s --help' for more information.", argv[0]);
743 exit(EXIT_FAILURE);
744 case QEMU_NBD_OPT_OBJECT:
745 user_creatable_process_cmdline(optarg);
746 break;
747 case QEMU_NBD_OPT_TLSCREDS:
748 tlscredsid = optarg;
749 break;
750 case QEMU_NBD_OPT_IMAGE_OPTS:
751 imageOpts = true;
752 break;
753 case 'T':
754 trace_opt_parse(optarg);
755 break;
756 case QEMU_NBD_OPT_TLSAUTHZ:
757 tlsauthz = optarg;
758 break;
759 case QEMU_NBD_OPT_FORK:
760 fork_process = true;
761 break;
762 case 'L':
763 list = true;
764 break;
765 case QEMU_NBD_OPT_PID_FILE:
766 pid_file_name = optarg;
767 break;
768 case QEMU_NBD_OPT_SELINUX_LABEL:
769 selinux_label = optarg;
770 break;
771 }
772 }
773
774 if (list) {
775 if (argc != optind) {
776 error_report("List mode is incompatible with a file name");
777 exit(EXIT_FAILURE);
778 }
779 if (export_name || export_description || dev_offset ||
780 device || disconnect || fmt || sn_id_or_name || bitmaps ||
781 alloc_depth || seen_aio || seen_discard || seen_cache) {
782 error_report("List mode is incompatible with per-device settings");
783 exit(EXIT_FAILURE);
784 }
785 if (fork_process) {
786 error_report("List mode is incompatible with forking");
787 exit(EXIT_FAILURE);
788 }
789 } else if ((argc - optind) != 1) {
790 error_report("Invalid number of arguments");
791 error_printf("Try `%s --help' for more information.\n", argv[0]);
792 exit(EXIT_FAILURE);
793 } else if (!export_name) {
794 export_name = "";
795 }
796
797 if (!trace_init_backends()) {
798 exit(1);
799 }
800 trace_init_file();
801 qemu_set_log(LOG_TRACE);
802
803 socket_activation = check_socket_activation();
804 if (socket_activation == 0) {
805 setup_address_and_port(&bindto, &port);
806 } else {
807 /* Using socket activation - check user didn't use -p etc. */
808 const char *err_msg = socket_activation_validate_opts(device, sockpath,
809 bindto, port,
810 selinux_label,
811 list);
812 if (err_msg != NULL) {
813 error_report("%s", err_msg);
814 exit(EXIT_FAILURE);
815 }
816
817 /* qemu-nbd can only listen on a single socket. */
818 if (socket_activation > 1) {
819 error_report("qemu-nbd does not support socket activation with %s > 1",
820 "LISTEN_FDS");
821 exit(EXIT_FAILURE);
822 }
823 }
824
825 if (tlscredsid) {
826 if (sockpath) {
827 error_report("TLS is only supported with IPv4/IPv6");
828 exit(EXIT_FAILURE);
829 }
830 if (device) {
831 error_report("TLS is not supported with a host device");
832 exit(EXIT_FAILURE);
833 }
834 if (tlsauthz && list) {
835 error_report("TLS authorization is incompatible with export list");
836 exit(EXIT_FAILURE);
837 }
838 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
839 if (local_err) {
840 error_reportf_err(local_err, "Failed to get TLS creds: ");
841 exit(EXIT_FAILURE);
842 }
843 } else {
844 if (tlsauthz) {
845 error_report("--tls-authz is not permitted without --tls-creds");
846 exit(EXIT_FAILURE);
847 }
848 }
849
850 if (selinux_label) {
851 #ifdef CONFIG_SELINUX
852 if (sockpath == NULL && device == NULL) {
853 error_report("--selinux-label is not permitted without --socket");
854 exit(EXIT_FAILURE);
855 }
856 #else
857 error_report("SELinux support not enabled in this binary");
858 exit(EXIT_FAILURE);
859 #endif
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 int backlog;
969
970 if (persistent || shared == 0) {
971 backlog = SOMAXCONN;
972 } else {
973 backlog = MIN(shared, SOMAXCONN);
974 }
975 #ifdef CONFIG_SELINUX
976 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) {
977 error_report("Cannot set SELinux socket create context to %s: %s",
978 selinux_label, strerror(errno));
979 exit(EXIT_FAILURE);
980 }
981 #endif
982 saddr = nbd_build_socket_address(sockpath, bindto, port);
983 if (qio_net_listener_open_sync(server, saddr, backlog,
984 &local_err) < 0) {
985 object_unref(OBJECT(server));
986 error_report_err(local_err);
987 exit(EXIT_FAILURE);
988 }
989 #ifdef CONFIG_SELINUX
990 if (selinux_label && setsockcreatecon_raw(NULL) == -1) {
991 error_report("Cannot clear SELinux socket create context: %s",
992 strerror(errno));
993 exit(EXIT_FAILURE);
994 }
995 #endif
996 } else {
997 size_t i;
998 /* See comment in check_socket_activation above. */
999 for (i = 0; i < socket_activation; i++) {
1000 QIOChannelSocket *sioc;
1001 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1002 &local_err);
1003 if (sioc == NULL) {
1004 object_unref(OBJECT(server));
1005 error_reportf_err(local_err,
1006 "Failed to use socket activation: ");
1007 exit(EXIT_FAILURE);
1008 }
1009 qio_net_listener_add(server, sioc);
1010 object_unref(OBJECT(sioc));
1011 }
1012 }
1013
1014 qemu_init_main_loop(&error_fatal);
1015 bdrv_init();
1016 atexit(qemu_nbd_shutdown);
1017
1018 srcpath = argv[optind];
1019 if (imageOpts) {
1020 QemuOpts *opts;
1021 if (fmt) {
1022 error_report("--image-opts and -f are mutually exclusive");
1023 exit(EXIT_FAILURE);
1024 }
1025 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1026 if (!opts) {
1027 qemu_opts_reset(&file_opts);
1028 exit(EXIT_FAILURE);
1029 }
1030 options = qemu_opts_to_qdict(opts, NULL);
1031 qemu_opts_reset(&file_opts);
1032 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1033 } else {
1034 if (fmt) {
1035 options = qdict_new();
1036 qdict_put_str(options, "driver", fmt);
1037 }
1038 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1039 }
1040
1041 if (!blk) {
1042 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1043 argv[optind]);
1044 exit(EXIT_FAILURE);
1045 }
1046 bs = blk_bs(blk);
1047
1048 if (dev_offset) {
1049 QDict *raw_opts = qdict_new();
1050 qdict_put_str(raw_opts, "driver", "raw");
1051 qdict_put_str(raw_opts, "file", bs->node_name);
1052 qdict_put_int(raw_opts, "offset", dev_offset);
1053 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1054 blk_remove_bs(blk);
1055 blk_insert_bs(blk, bs, &error_fatal);
1056 bdrv_unref(bs);
1057 }
1058
1059 blk_set_enable_write_cache(blk, !writethrough);
1060
1061 if (sn_opts) {
1062 ret = bdrv_snapshot_load_tmp(bs,
1063 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1064 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1065 &local_err);
1066 } else if (sn_id_or_name) {
1067 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1068 &local_err);
1069 }
1070 if (ret < 0) {
1071 error_reportf_err(local_err, "Failed to load snapshot: ");
1072 exit(EXIT_FAILURE);
1073 }
1074
1075 bs->detect_zeroes = detect_zeroes;
1076
1077 nbd_server_is_qemu_nbd(true);
1078
1079 export_opts = g_new(BlockExportOptions, 1);
1080 *export_opts = (BlockExportOptions) {
1081 .type = BLOCK_EXPORT_TYPE_NBD,
1082 .id = g_strdup("qemu-nbd-export"),
1083 .node_name = g_strdup(bdrv_get_node_name(bs)),
1084 .has_writethrough = true,
1085 .writethrough = writethrough,
1086 .has_writable = true,
1087 .writable = !readonly,
1088 .u.nbd = {
1089 .has_name = true,
1090 .name = g_strdup(export_name),
1091 .has_description = !!export_description,
1092 .description = g_strdup(export_description),
1093 .has_bitmaps = !!bitmaps,
1094 .bitmaps = bitmaps,
1095 .has_allocation_depth = alloc_depth,
1096 .allocation_depth = alloc_depth,
1097 },
1098 };
1099 blk_exp_add(export_opts, &error_fatal);
1100 qapi_free_BlockExportOptions(export_opts);
1101
1102 if (device) {
1103 #if HAVE_NBD_DEVICE
1104 int ret;
1105
1106 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1107 if (ret != 0) {
1108 error_report("Failed to create client thread: %s", strerror(ret));
1109 exit(EXIT_FAILURE);
1110 }
1111 #endif
1112 } else {
1113 /* Shut up GCC warnings. */
1114 memset(&client_thread, 0, sizeof(client_thread));
1115 }
1116
1117 nbd_update_server_watch();
1118
1119 if (pid_file_name) {
1120 qemu_write_pidfile(pid_file_name, &error_fatal);
1121 }
1122
1123 /* now when the initialization is (almost) complete, chdir("/")
1124 * to free any busy filesystems */
1125 if (chdir("/") < 0) {
1126 error_report("Could not chdir to root directory: %s",
1127 strerror(errno));
1128 exit(EXIT_FAILURE);
1129 }
1130
1131 if (fork_process) {
1132 dup2(old_stderr, STDERR_FILENO);
1133 close(old_stderr);
1134 }
1135
1136 state = RUNNING;
1137 do {
1138 main_loop_wait(false);
1139 if (state == TERMINATE) {
1140 blk_exp_close_all();
1141 state = TERMINATED;
1142 }
1143 } while (state != TERMINATED);
1144
1145 blk_unref(blk);
1146 if (sockpath) {
1147 unlink(sockpath);
1148 }
1149
1150 qemu_opts_del(sn_opts);
1151
1152 if (device) {
1153 void *ret;
1154 pthread_join(client_thread, &ret);
1155 exit(ret != NULL);
1156 } else {
1157 exit(EXIT_SUCCESS);
1158 }
1159 }