sockets: Bypass "replace empty @path" for abstract unix sockets
[qemu/ar7.git] / qemu-nbd.c
blob75ced65030157c213498eedd29dd6f8a4c4aed40
1 /*
2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
4 * Network Block Device
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.
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.
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/>.
19 #include "qemu/osdep.h"
20 #include <getopt.h>
21 #include <libgen.h>
22 #include <pthread.h>
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"
49 #ifdef __linux__
50 #define HAVE_NBD_DEVICE 1
51 #else
52 #define HAVE_NBD_DEVICE 0
53 #endif
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
67 #define MBR_SIZE 512
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;
80 static void usage(const char *name)
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");
147 static void version(const char *name)
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);
159 #ifdef CONFIG_POSIX
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.
164 void qemu_system_killed(int signum, pid_t pid)
166 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
167 qemu_notify_event();
169 #endif /* CONFIG_POSIX */
171 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
172 const char *hostname)
174 int ret = EXIT_FAILURE;
175 int rc;
176 Error *err = NULL;
177 QIOChannelSocket *sioc;
178 NBDExportInfo *list;
179 int i, j;
181 sioc = qio_channel_socket_new();
182 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
183 error_report_err(err);
184 return EXIT_FAILURE;
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);
192 goto out;
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);
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",
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]);
222 printf(" )\n");
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);
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]);
236 nbd_free_export_list(list, rc);
238 ret = EXIT_SUCCESS;
239 out:
240 object_unref(OBJECT(sioc));
241 return ret;
245 #if HAVE_NBD_DEVICE
246 static void *show_parts(void *arg)
248 char *device = arg;
249 int nbd;
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
256 nbd = open(device, O_RDWR);
257 if (nbd >= 0) {
258 close(nbd);
260 return NULL;
263 static void *nbd_client_thread(void *arg)
265 char *device = arg;
266 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
267 QIOChannelSocket *sioc;
268 int fd;
269 int ret;
270 pthread_t show_parts_thread;
271 Error *local_error = NULL;
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;
281 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc),
282 NULL, NULL, NULL, &info, &local_error);
283 if (ret < 0) {
284 if (local_error) {
285 error_report_err(local_error);
287 goto out_socket;
290 fd = open(device, O_RDWR);
291 if (fd < 0) {
292 /* Linux-only, we can use %m in printf. */
293 error_report("Failed to open %s: %m", device);
294 goto out_socket;
297 ret = nbd_init(fd, sioc, &info, &local_error);
298 if (ret < 0) {
299 error_report_err(local_error);
300 goto out_fd;
303 /* update partition table */
304 pthread_create(&show_parts_thread, NULL, show_parts, device);
306 if (verbose) {
307 fprintf(stderr, "NBD device %s is now connected to %s\n",
308 device, srcpath);
309 } else {
310 /* Close stderr so that the qemu-nbd process exits. */
311 dup2(STDOUT_FILENO, STDERR_FILENO);
314 ret = nbd_client(fd);
315 if (ret) {
316 goto out_fd;
318 close(fd);
319 object_unref(OBJECT(sioc));
320 g_free(info.name);
321 kill(getpid(), SIGTERM);
322 return (void *) EXIT_SUCCESS;
324 out_fd:
325 close(fd);
326 out_socket:
327 object_unref(OBJECT(sioc));
328 out:
329 g_free(info.name);
330 kill(getpid(), SIGTERM);
331 return (void *) EXIT_FAILURE;
333 #endif /* HAVE_NBD_DEVICE */
335 static int nbd_can_accept(void)
337 return state == RUNNING && nb_fds < shared;
340 static void nbd_update_server_watch(void);
342 static void nbd_client_closed(NBDClient *client, bool negotiated)
344 nb_fds--;
345 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
346 state = TERMINATE;
348 nbd_update_server_watch();
349 nbd_client_put(client);
352 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
353 gpointer opaque)
355 if (state >= TERMINATE) {
356 return;
359 nb_fds++;
360 nbd_update_server_watch();
361 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
364 static void nbd_update_server_watch(void)
366 if (nbd_can_accept()) {
367 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
368 } else {
369 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
374 static SocketAddress *nbd_build_socket_address(const char *sockpath,
375 const char *bindto,
376 const char *port)
378 SocketAddress *saddr;
380 saddr = g_new0(SocketAddress, 1);
381 if (sockpath) {
382 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
383 saddr->u.q_unix.path = g_strdup(sockpath);
384 } else {
385 InetSocketAddress *inet;
386 saddr->type = SOCKET_ADDRESS_TYPE_INET;
387 inet = &saddr->u.inet;
388 inet->host = g_strdup(bindto);
389 if (port) {
390 inet->port = g_strdup(port);
391 } else {
392 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
396 return saddr;
400 static QemuOptsList file_opts = {
401 .name = "file",
402 .implied_opt_name = "file",
403 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
404 .desc = {
405 /* no elements => accept any params */
406 { /* end of list */ }
410 static QemuOptsList qemu_object_opts = {
411 .name = "object",
412 .implied_opt_name = "qom-type",
413 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
414 .desc = {
419 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
421 if (user_creatable_print_help(type, opts)) {
422 exit(0);
424 return true;
428 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
429 Error **errp)
431 Object *obj;
432 QCryptoTLSCreds *creds;
434 obj = object_resolve_path_component(
435 object_get_objects_root(), id);
436 if (!obj) {
437 error_setg(errp, "No TLS credentials with id '%s'",
438 id);
439 return NULL;
441 creds = (QCryptoTLSCreds *)
442 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
443 if (!creds) {
444 error_setg(errp, "Object with id '%s' is not TLS credentials",
445 id);
446 return NULL;
449 if (list) {
450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
451 error_setg(errp,
452 "Expecting TLS credentials with a client endpoint");
453 return NULL;
455 } else {
456 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
457 error_setg(errp,
458 "Expecting TLS credentials with a server endpoint");
459 return NULL;
462 object_ref(obj);
463 return creds;
466 static void setup_address_and_port(const char **address, const char **port)
468 if (*address == NULL) {
469 *address = "0.0.0.0";
472 if (*port == NULL) {
473 *port = stringify(NBD_DEFAULT_PORT);
478 * Check socket parameters compatibility when socket activation is used.
480 static const char *socket_activation_validate_opts(const char *device,
481 const char *sockpath,
482 const char *address,
483 const char *port,
484 bool list)
486 if (device != NULL) {
487 return "NBD device can't be set when using socket activation";
490 if (sockpath != NULL) {
491 return "Unix socket can't be set when using socket activation";
494 if (address != NULL) {
495 return "The interface can't be set when using socket activation";
498 if (port != NULL) {
499 return "TCP port number can't be set when using socket activation";
502 if (list) {
503 return "List mode is incompatible with socket activation";
506 return NULL;
509 static void qemu_nbd_shutdown(void)
511 job_cancel_sync_all();
512 bdrv_close_all();
515 int main(int argc, char **argv)
517 BlockBackend *blk;
518 BlockDriverState *bs;
519 uint64_t dev_offset = 0;
520 bool readonly = false;
521 bool disconnect = false;
522 const char *bindto = NULL;
523 const char *port = NULL;
524 char *sockpath = NULL;
525 char *device = NULL;
526 QemuOpts *sn_opts = NULL;
527 const char *sn_id_or_name = NULL;
528 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L";
529 struct option lopt[] = {
530 { "help", no_argument, NULL, 'h' },
531 { "version", no_argument, NULL, 'V' },
532 { "bind", required_argument, NULL, 'b' },
533 { "port", required_argument, NULL, 'p' },
534 { "socket", required_argument, NULL, 'k' },
535 { "offset", required_argument, NULL, 'o' },
536 { "read-only", no_argument, NULL, 'r' },
537 { "allocation-depth", no_argument, NULL, 'A' },
538 { "bitmap", required_argument, NULL, 'B' },
539 { "connect", required_argument, NULL, 'c' },
540 { "disconnect", no_argument, NULL, 'd' },
541 { "list", no_argument, NULL, 'L' },
542 { "snapshot", no_argument, NULL, 's' },
543 { "load-snapshot", required_argument, NULL, 'l' },
544 { "nocache", no_argument, NULL, 'n' },
545 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
546 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
547 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
548 { "detect-zeroes", required_argument, NULL,
549 QEMU_NBD_OPT_DETECT_ZEROES },
550 { "shared", required_argument, NULL, 'e' },
551 { "format", required_argument, NULL, 'f' },
552 { "persistent", no_argument, NULL, 't' },
553 { "verbose", no_argument, NULL, 'v' },
554 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
555 { "export-name", required_argument, NULL, 'x' },
556 { "description", required_argument, NULL, 'D' },
557 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
558 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
559 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
560 { "trace", required_argument, NULL, 'T' },
561 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
562 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE },
563 { NULL, 0, NULL, 0 }
565 int ch;
566 int opt_ind = 0;
567 int flags = BDRV_O_RDWR;
568 int ret = 0;
569 bool seen_cache = false;
570 bool seen_discard = false;
571 bool seen_aio = false;
572 pthread_t client_thread;
573 const char *fmt = NULL;
574 Error *local_err = NULL;
575 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
576 QDict *options = NULL;
577 const char *export_name = NULL; /* defaults to "" later for server mode */
578 const char *export_description = NULL;
579 strList *bitmaps = NULL;
580 bool alloc_depth = false;
581 const char *tlscredsid = NULL;
582 bool imageOpts = false;
583 bool writethrough = true;
584 char *trace_file = NULL;
585 bool fork_process = false;
586 bool list = false;
587 int old_stderr = -1;
588 unsigned socket_activation;
589 const char *pid_file_name = NULL;
590 BlockExportOptions *export_opts;
592 #ifdef CONFIG_POSIX
593 os_setup_early_signal_handling();
594 os_setup_signal_handling();
595 #endif
597 socket_init();
598 error_init(argv[0]);
599 module_call_init(MODULE_INIT_TRACE);
600 qcrypto_init(&error_fatal);
602 module_call_init(MODULE_INIT_QOM);
603 qemu_add_opts(&qemu_object_opts);
604 qemu_add_opts(&qemu_trace_opts);
605 qemu_init_exec_dir(argv[0]);
607 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
608 switch (ch) {
609 case 's':
610 flags |= BDRV_O_SNAPSHOT;
611 break;
612 case 'n':
613 optarg = (char *) "none";
614 /* fallthrough */
615 case QEMU_NBD_OPT_CACHE:
616 if (seen_cache) {
617 error_report("-n and --cache can only be specified once");
618 exit(EXIT_FAILURE);
620 seen_cache = true;
621 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
622 error_report("Invalid cache mode `%s'", optarg);
623 exit(EXIT_FAILURE);
625 break;
626 case QEMU_NBD_OPT_AIO:
627 if (seen_aio) {
628 error_report("--aio can only be specified once");
629 exit(EXIT_FAILURE);
631 seen_aio = true;
632 if (bdrv_parse_aio(optarg, &flags) < 0) {
633 error_report("Invalid aio mode '%s'", optarg);
634 exit(EXIT_FAILURE);
636 break;
637 case QEMU_NBD_OPT_DISCARD:
638 if (seen_discard) {
639 error_report("--discard can only be specified once");
640 exit(EXIT_FAILURE);
642 seen_discard = true;
643 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
644 error_report("Invalid discard mode `%s'", optarg);
645 exit(EXIT_FAILURE);
647 break;
648 case QEMU_NBD_OPT_DETECT_ZEROES:
649 detect_zeroes =
650 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
651 optarg,
652 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
653 &local_err);
654 if (local_err) {
655 error_reportf_err(local_err,
656 "Failed to parse detect_zeroes mode: ");
657 exit(EXIT_FAILURE);
659 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
660 !(flags & BDRV_O_UNMAP)) {
661 error_report("setting detect-zeroes to unmap is not allowed "
662 "without setting discard operation to unmap");
663 exit(EXIT_FAILURE);
665 break;
666 case 'b':
667 bindto = optarg;
668 break;
669 case 'p':
670 port = optarg;
671 break;
672 case 'o':
673 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
674 error_report("Invalid offset '%s'", optarg);
675 exit(EXIT_FAILURE);
677 break;
678 case 'l':
679 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
680 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
681 optarg, false);
682 if (!sn_opts) {
683 error_report("Failed in parsing snapshot param `%s'",
684 optarg);
685 exit(EXIT_FAILURE);
687 } else {
688 sn_id_or_name = optarg;
690 /* fall through */
691 case 'r':
692 readonly = true;
693 flags &= ~BDRV_O_RDWR;
694 break;
695 case 'A':
696 alloc_depth = true;
697 break;
698 case 'B':
699 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg));
700 break;
701 case 'k':
702 sockpath = optarg;
703 if (sockpath[0] != '/') {
704 error_report("socket path must be absolute");
705 exit(EXIT_FAILURE);
707 break;
708 case 'd':
709 disconnect = true;
710 break;
711 case 'c':
712 device = optarg;
713 break;
714 case 'e':
715 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
716 shared < 1) {
717 error_report("Invalid shared device number '%s'", optarg);
718 exit(EXIT_FAILURE);
720 break;
721 case 'f':
722 fmt = optarg;
723 break;
724 case 't':
725 persistent = 1;
726 break;
727 case 'x':
728 export_name = optarg;
729 if (strlen(export_name) > NBD_MAX_STRING_SIZE) {
730 error_report("export name '%s' too long", export_name);
731 exit(EXIT_FAILURE);
733 break;
734 case 'D':
735 export_description = optarg;
736 if (strlen(export_description) > NBD_MAX_STRING_SIZE) {
737 error_report("export description '%s' too long",
738 export_description);
739 exit(EXIT_FAILURE);
741 break;
742 case 'v':
743 verbose = 1;
744 break;
745 case 'V':
746 version(argv[0]);
747 exit(0);
748 break;
749 case 'h':
750 usage(argv[0]);
751 exit(0);
752 break;
753 case '?':
754 error_report("Try `%s --help' for more information.", argv[0]);
755 exit(EXIT_FAILURE);
756 case QEMU_NBD_OPT_OBJECT: {
757 QemuOpts *opts;
758 opts = qemu_opts_parse_noisily(&qemu_object_opts,
759 optarg, true);
760 if (!opts) {
761 exit(EXIT_FAILURE);
763 } break;
764 case QEMU_NBD_OPT_TLSCREDS:
765 tlscredsid = optarg;
766 break;
767 case QEMU_NBD_OPT_IMAGE_OPTS:
768 imageOpts = true;
769 break;
770 case 'T':
771 g_free(trace_file);
772 trace_file = trace_opt_parse(optarg);
773 break;
774 case QEMU_NBD_OPT_TLSAUTHZ:
775 tlsauthz = optarg;
776 break;
777 case QEMU_NBD_OPT_FORK:
778 fork_process = true;
779 break;
780 case 'L':
781 list = true;
782 break;
783 case QEMU_NBD_OPT_PID_FILE:
784 pid_file_name = optarg;
785 break;
789 if (list) {
790 if (argc != optind) {
791 error_report("List mode is incompatible with a file name");
792 exit(EXIT_FAILURE);
794 if (export_name || export_description || dev_offset ||
795 device || disconnect || fmt || sn_id_or_name || bitmaps ||
796 alloc_depth || seen_aio || seen_discard || seen_cache) {
797 error_report("List mode is incompatible with per-device settings");
798 exit(EXIT_FAILURE);
800 if (fork_process) {
801 error_report("List mode is incompatible with forking");
802 exit(EXIT_FAILURE);
804 } else if ((argc - optind) != 1) {
805 error_report("Invalid number of arguments");
806 error_printf("Try `%s --help' for more information.\n", argv[0]);
807 exit(EXIT_FAILURE);
808 } else if (!export_name) {
809 export_name = "";
812 qemu_opts_foreach(&qemu_object_opts,
813 user_creatable_add_opts_foreach,
814 qemu_nbd_object_print_help, &error_fatal);
816 if (!trace_init_backends()) {
817 exit(1);
819 trace_init_file(trace_file);
820 qemu_set_log(LOG_TRACE);
822 socket_activation = check_socket_activation();
823 if (socket_activation == 0) {
824 setup_address_and_port(&bindto, &port);
825 } else {
826 /* Using socket activation - check user didn't use -p etc. */
827 const char *err_msg = socket_activation_validate_opts(device, sockpath,
828 bindto, port,
829 list);
830 if (err_msg != NULL) {
831 error_report("%s", err_msg);
832 exit(EXIT_FAILURE);
835 /* qemu-nbd can only listen on a single socket. */
836 if (socket_activation > 1) {
837 error_report("qemu-nbd does not support socket activation with %s > 1",
838 "LISTEN_FDS");
839 exit(EXIT_FAILURE);
843 if (tlscredsid) {
844 if (sockpath) {
845 error_report("TLS is only supported with IPv4/IPv6");
846 exit(EXIT_FAILURE);
848 if (device) {
849 error_report("TLS is not supported with a host device");
850 exit(EXIT_FAILURE);
852 if (tlsauthz && list) {
853 error_report("TLS authorization is incompatible with export list");
854 exit(EXIT_FAILURE);
856 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
857 if (local_err) {
858 error_reportf_err(local_err, "Failed to get TLS creds: ");
859 exit(EXIT_FAILURE);
861 } else {
862 if (tlsauthz) {
863 error_report("--tls-authz is not permitted without --tls-creds");
864 exit(EXIT_FAILURE);
868 if (list) {
869 saddr = nbd_build_socket_address(sockpath, bindto, port);
870 return qemu_nbd_client_list(saddr, tlscreds, bindto);
873 #if !HAVE_NBD_DEVICE
874 if (disconnect || device) {
875 error_report("Kernel /dev/nbdN support not available");
876 exit(EXIT_FAILURE);
878 #else /* HAVE_NBD_DEVICE */
879 if (disconnect) {
880 int nbdfd = open(argv[optind], O_RDWR);
881 if (nbdfd < 0) {
882 error_report("Cannot open %s: %s", argv[optind],
883 strerror(errno));
884 exit(EXIT_FAILURE);
886 nbd_disconnect(nbdfd);
888 close(nbdfd);
890 printf("%s disconnected\n", argv[optind]);
892 return 0;
894 #endif
896 if ((device && !verbose) || fork_process) {
897 #ifndef WIN32
898 int stderr_fd[2];
899 pid_t pid;
900 int ret;
902 if (qemu_pipe(stderr_fd) < 0) {
903 error_report("Error setting up communication pipe: %s",
904 strerror(errno));
905 exit(EXIT_FAILURE);
908 /* Now daemonize, but keep a communication channel open to
909 * print errors and exit with the proper status code.
911 pid = fork();
912 if (pid < 0) {
913 error_report("Failed to fork: %s", strerror(errno));
914 exit(EXIT_FAILURE);
915 } else if (pid == 0) {
916 close(stderr_fd[0]);
918 /* Remember parent's stderr if we will be restoring it. */
919 if (fork_process) {
920 old_stderr = dup(STDERR_FILENO);
923 ret = qemu_daemon(1, 0);
925 /* Temporarily redirect stderr to the parent's pipe... */
926 dup2(stderr_fd[1], STDERR_FILENO);
927 if (ret < 0) {
928 error_report("Failed to daemonize: %s", strerror(errno));
929 exit(EXIT_FAILURE);
932 /* ... close the descriptor we inherited and go on. */
933 close(stderr_fd[1]);
934 } else {
935 bool errors = false;
936 char *buf;
938 /* In the parent. Print error messages from the child until
939 * it closes the pipe.
941 close(stderr_fd[1]);
942 buf = g_malloc(1024);
943 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
944 errors = true;
945 ret = qemu_write_full(STDERR_FILENO, buf, ret);
946 if (ret < 0) {
947 exit(EXIT_FAILURE);
950 if (ret < 0) {
951 error_report("Cannot read from daemon: %s",
952 strerror(errno));
953 exit(EXIT_FAILURE);
956 /* Usually the daemon should not print any message.
957 * Exit with zero status in that case.
959 exit(errors);
961 #else /* WIN32 */
962 error_report("Unable to fork into background on Windows hosts");
963 exit(EXIT_FAILURE);
964 #endif /* WIN32 */
967 if (device != NULL && sockpath == NULL) {
968 sockpath = g_malloc(128);
969 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
972 server = qio_net_listener_new();
973 if (socket_activation == 0) {
974 saddr = nbd_build_socket_address(sockpath, bindto, port);
975 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) {
976 object_unref(OBJECT(server));
977 error_report_err(local_err);
978 exit(EXIT_FAILURE);
980 } else {
981 size_t i;
982 /* See comment in check_socket_activation above. */
983 for (i = 0; i < socket_activation; i++) {
984 QIOChannelSocket *sioc;
985 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
986 &local_err);
987 if (sioc == NULL) {
988 object_unref(OBJECT(server));
989 error_reportf_err(local_err,
990 "Failed to use socket activation: ");
991 exit(EXIT_FAILURE);
993 qio_net_listener_add(server, sioc);
994 object_unref(OBJECT(sioc));
998 if (qemu_init_main_loop(&local_err)) {
999 error_report_err(local_err);
1000 exit(EXIT_FAILURE);
1002 bdrv_init();
1003 atexit(qemu_nbd_shutdown);
1005 srcpath = argv[optind];
1006 if (imageOpts) {
1007 QemuOpts *opts;
1008 if (fmt) {
1009 error_report("--image-opts and -f are mutually exclusive");
1010 exit(EXIT_FAILURE);
1012 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1013 if (!opts) {
1014 qemu_opts_reset(&file_opts);
1015 exit(EXIT_FAILURE);
1017 options = qemu_opts_to_qdict(opts, NULL);
1018 qemu_opts_reset(&file_opts);
1019 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1020 } else {
1021 if (fmt) {
1022 options = qdict_new();
1023 qdict_put_str(options, "driver", fmt);
1025 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1028 if (!blk) {
1029 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1030 argv[optind]);
1031 exit(EXIT_FAILURE);
1033 bs = blk_bs(blk);
1035 if (dev_offset) {
1036 QDict *raw_opts = qdict_new();
1037 qdict_put_str(raw_opts, "driver", "raw");
1038 qdict_put_str(raw_opts, "file", bs->node_name);
1039 qdict_put_int(raw_opts, "offset", dev_offset);
1040 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal);
1041 blk_remove_bs(blk);
1042 blk_insert_bs(blk, bs, &error_fatal);
1043 bdrv_unref(bs);
1046 blk_set_enable_write_cache(blk, !writethrough);
1048 if (sn_opts) {
1049 ret = bdrv_snapshot_load_tmp(bs,
1050 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1051 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1052 &local_err);
1053 } else if (sn_id_or_name) {
1054 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1055 &local_err);
1057 if (ret < 0) {
1058 error_reportf_err(local_err, "Failed to load snapshot: ");
1059 exit(EXIT_FAILURE);
1062 bs->detect_zeroes = detect_zeroes;
1064 nbd_server_is_qemu_nbd(true);
1066 export_opts = g_new(BlockExportOptions, 1);
1067 *export_opts = (BlockExportOptions) {
1068 .type = BLOCK_EXPORT_TYPE_NBD,
1069 .id = g_strdup("qemu-nbd-export"),
1070 .node_name = g_strdup(bdrv_get_node_name(bs)),
1071 .has_writethrough = true,
1072 .writethrough = writethrough,
1073 .has_writable = true,
1074 .writable = !readonly,
1075 .u.nbd = {
1076 .has_name = true,
1077 .name = g_strdup(export_name),
1078 .has_description = !!export_description,
1079 .description = g_strdup(export_description),
1080 .has_bitmaps = !!bitmaps,
1081 .bitmaps = bitmaps,
1082 .has_allocation_depth = alloc_depth,
1083 .allocation_depth = alloc_depth,
1086 blk_exp_add(export_opts, &error_fatal);
1087 qapi_free_BlockExportOptions(export_opts);
1089 if (device) {
1090 #if HAVE_NBD_DEVICE
1091 int ret;
1093 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1094 if (ret != 0) {
1095 error_report("Failed to create client thread: %s", strerror(ret));
1096 exit(EXIT_FAILURE);
1098 #endif
1099 } else {
1100 /* Shut up GCC warnings. */
1101 memset(&client_thread, 0, sizeof(client_thread));
1104 nbd_update_server_watch();
1106 if (pid_file_name) {
1107 qemu_write_pidfile(pid_file_name, &error_fatal);
1110 /* now when the initialization is (almost) complete, chdir("/")
1111 * to free any busy filesystems */
1112 if (chdir("/") < 0) {
1113 error_report("Could not chdir to root directory: %s",
1114 strerror(errno));
1115 exit(EXIT_FAILURE);
1118 if (fork_process) {
1119 dup2(old_stderr, STDERR_FILENO);
1120 close(old_stderr);
1123 state = RUNNING;
1124 do {
1125 main_loop_wait(false);
1126 if (state == TERMINATE) {
1127 blk_exp_close_all();
1128 state = TERMINATED;
1130 } while (state != TERMINATED);
1132 blk_unref(blk);
1133 if (sockpath) {
1134 unlink(sockpath);
1137 qemu_opts_del(sn_opts);
1139 if (device) {
1140 void *ret;
1141 pthread_join(client_thread, &ret);
1142 exit(ret != NULL);
1143 } else {
1144 exit(EXIT_SUCCESS);