2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
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"
24 #include "qemu-common.h"
25 #include "qapi/error.h"
26 #include "qemu/cutils.h"
27 #include "sysemu/block-backend.h"
28 #include "block/block_int.h"
29 #include "block/nbd.h"
30 #include "qemu/main-loop.h"
31 #include "qemu/module.h"
32 #include "qemu/option.h"
33 #include "qemu/error-report.h"
34 #include "qemu/config-file.h"
35 #include "qemu/bswap.h"
37 #include "qemu/systemd.h"
38 #include "block/snapshot.h"
39 #include "qapi/qmp/qdict.h"
40 #include "qapi/qmp/qstring.h"
41 #include "qom/object_interfaces.h"
42 #include "io/channel-socket.h"
43 #include "io/net-listener.h"
44 #include "crypto/init.h"
45 #include "trace/control.h"
46 #include "qemu-version.h"
49 #define HAVE_NBD_DEVICE 1
51 #define HAVE_NBD_DEVICE 0
54 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
55 #define QEMU_NBD_OPT_CACHE 256
56 #define QEMU_NBD_OPT_AIO 257
57 #define QEMU_NBD_OPT_DISCARD 258
58 #define QEMU_NBD_OPT_DETECT_ZEROES 259
59 #define QEMU_NBD_OPT_OBJECT 260
60 #define QEMU_NBD_OPT_TLSCREDS 261
61 #define QEMU_NBD_OPT_IMAGE_OPTS 262
62 #define QEMU_NBD_OPT_FORK 263
63 #define QEMU_NBD_OPT_TLSAUTHZ 264
67 static NBDExport *export;
70 static SocketAddress *saddr;
71 static int persistent = 0;
72 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
73 static int shared = 1;
75 static QIONetListener *server;
76 static QCryptoTLSCreds *tlscreds;
77 static const char *tlsauthz;
79 static void usage(const char *name)
82 "Usage: %s [OPTIONS] FILE\n"
83 " or: %s -L [OPTIONS]\n"
84 "QEMU Disk Network Block Device Utility\n"
86 " -h, --help display this help and exit\n"
87 " -V, --version output version information and exit\n"
89 "Connection properties:\n"
90 " -p, --port=PORT port to listen on (default `%d')\n"
91 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
92 " -k, --socket=PATH path to the unix socket\n"
93 " (default '"SOCKET_PATH"')\n"
94 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
95 " -t, --persistent don't exit on the last connection\n"
96 " -v, --verbose display extra debugging information\n"
97 " -x, --export-name=NAME expose export by name (default is empty string)\n"
98 " -D, --description=TEXT export a human-readable description\n"
100 "Exposing part of the image:\n"
101 " -o, --offset=OFFSET offset into the image\n"
102 " -P, --partition=NUM only expose partition NUM\n"
103 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
105 "General purpose options:\n"
106 " -L, --list list exports available from another NBD server\n"
107 " --object type,id=ID,... define an object such as 'secret' for providing\n"
108 " passwords and/or encryption keys\n"
109 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
110 " --tls-authz=ID use id of an earlier --object to provide\n"
112 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
113 " specify tracing options\n"
114 " --fork fork off the server process and exit the parent\n"
115 " once the server is running\n"
118 "Kernel NBD client support:\n"
119 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
120 " -d, --disconnect disconnect the specified device\n"
123 "Block device options:\n"
124 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
125 " -r, --read-only export read-only\n"
126 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
127 " file with backing_file=FILE, redirect the write to\n"
128 " the temporary one\n"
129 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
130 " load an internal snapshot inside FILE and export it\n"
131 " as an read-only device, SNAPSHOT_PARAM format is\n"
132 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
134 " -n, --nocache disable host cache\n"
135 " --cache=MODE set cache mode (none, writeback, ...)\n"
136 " --aio=MODE set AIO mode (native or threads)\n"
137 " --discard=MODE set discard mode (ignore, unmap)\n"
138 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
139 " --image-opts treat FILE as a full set of image options\n"
141 QEMU_HELP_BOTTOM "\n"
142 , name, name, NBD_DEFAULT_PORT, "DEVICE");
145 static void version(const char *name)
148 "%s " QEMU_FULL_VERSION "\n"
149 "Written by Anthony Liguori.\n"
152 "This is free software; see the source for copying conditions. There is NO\n"
153 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
157 struct partition_record
161 uint32_t start_cylinder;
162 uint8_t start_sector;
165 uint8_t end_cylinder;
167 uint32_t start_sector_abs;
168 uint32_t nb_sectors_abs;
171 static void read_partition(uint8_t *p, struct partition_record *r)
174 r->start_head = p[1];
175 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
176 r->start_sector = p[2] & 0x3f;
179 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
180 r->end_sector = p[6] & 0x3f;
182 r->start_sector_abs = ldl_le_p(p + 8);
183 r->nb_sectors_abs = ldl_le_p(p + 12);
186 static int find_partition(BlockBackend *blk, int partition,
187 uint64_t *offset, uint64_t *size)
189 struct partition_record mbr[4];
190 uint8_t data[MBR_SIZE];
195 ret = blk_pread(blk, 0, data, sizeof(data));
197 error_report("error while reading: %s", strerror(-ret));
201 if (data[510] != 0x55 || data[511] != 0xaa) {
205 for (i = 0; i < 4; i++) {
206 read_partition(&data[446 + 16 * i], &mbr[i]);
208 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
212 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
213 struct partition_record ext[4];
214 uint8_t data1[MBR_SIZE];
217 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE,
218 data1, sizeof(data1));
220 error_report("error while reading: %s", strerror(-ret));
224 for (j = 0; j < 4; j++) {
225 read_partition(&data1[446 + 16 * j], &ext[j]);
226 if (!ext[j].system || !ext[j].nb_sectors_abs) {
230 if ((ext_partnum + j + 1) == partition) {
231 *offset = (uint64_t)ext[j].start_sector_abs << 9;
232 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
237 } else if ((i + 1) == partition) {
238 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
239 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
247 static void termsig_handler(int signum)
249 atomic_cmpxchg(&state, RUNNING, TERMINATE);
254 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
255 const char *hostname)
257 int ret = EXIT_FAILURE;
260 QIOChannelSocket *sioc;
264 sioc = qio_channel_socket_new();
265 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
266 error_report_err(err);
269 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
273 error_report_err(err);
277 printf("exports available: %d\n", rc);
278 for (i = 0; i < rc; i++) {
279 printf(" export: '%s'\n", list[i].name);
280 if (list[i].description && *list[i].description) {
281 printf(" description: %s\n", list[i].description);
283 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
284 static const char *const flag_names[] = {
285 [NBD_FLAG_READ_ONLY_BIT] = "readonly",
286 [NBD_FLAG_SEND_FLUSH_BIT] = "flush",
287 [NBD_FLAG_SEND_FUA_BIT] = "fua",
288 [NBD_FLAG_ROTATIONAL_BIT] = "rotational",
289 [NBD_FLAG_SEND_TRIM_BIT] = "trim",
290 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes",
291 [NBD_FLAG_SEND_DF_BIT] = "df",
292 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi",
293 [NBD_FLAG_SEND_RESIZE_BIT] = "resize",
294 [NBD_FLAG_SEND_CACHE_BIT] = "cache",
297 printf(" size: %" PRIu64 "\n", list[i].size);
298 printf(" flags: 0x%x (", list[i].flags);
299 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) {
300 if (flag_names[bit] && (list[i].flags & (1 << bit))) {
301 printf(" %s", flag_names[bit]);
306 if (list[i].min_block) {
307 printf(" min block: %u\n", list[i].min_block);
308 printf(" opt block: %u\n", list[i].opt_block);
309 printf(" max block: %u\n", list[i].max_block);
311 if (list[i].n_contexts) {
312 printf(" available meta contexts: %d\n", list[i].n_contexts);
313 for (j = 0; j < list[i].n_contexts; j++) {
314 printf(" %s\n", list[i].contexts[j]);
318 nbd_free_export_list(list, rc);
322 object_unref(OBJECT(sioc));
328 static void *show_parts(void *arg)
333 /* linux just needs an open() to trigger
334 * the partition table update
335 * but remember to load the module with max_part != 0 :
336 * modprobe nbd max_part=63
338 nbd = open(device, O_RDWR);
345 static void *nbd_client_thread(void *arg)
348 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
349 QIOChannelSocket *sioc;
352 pthread_t show_parts_thread;
353 Error *local_error = NULL;
355 sioc = qio_channel_socket_new();
356 if (qio_channel_socket_connect_sync(sioc,
359 error_report_err(local_error);
363 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc),
364 NULL, NULL, NULL, &info, &local_error);
367 error_report_err(local_error);
372 fd = open(device, O_RDWR);
374 /* Linux-only, we can use %m in printf. */
375 error_report("Failed to open %s: %m", device);
379 ret = nbd_init(fd, sioc, &info, &local_error);
381 error_report_err(local_error);
385 /* update partition table */
386 pthread_create(&show_parts_thread, NULL, show_parts, device);
389 fprintf(stderr, "NBD device %s is now connected to %s\n",
392 /* Close stderr so that the qemu-nbd process exits. */
393 dup2(STDOUT_FILENO, STDERR_FILENO);
396 ret = nbd_client(fd);
401 object_unref(OBJECT(sioc));
403 kill(getpid(), SIGTERM);
404 return (void *) EXIT_SUCCESS;
409 object_unref(OBJECT(sioc));
412 kill(getpid(), SIGTERM);
413 return (void *) EXIT_FAILURE;
415 #endif /* HAVE_NBD_DEVICE */
417 static int nbd_can_accept(void)
419 return state == RUNNING && nb_fds < shared;
422 static void nbd_export_closed(NBDExport *export)
424 assert(state == TERMINATING);
428 static void nbd_update_server_watch(void);
430 static void nbd_client_closed(NBDClient *client, bool negotiated)
433 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
436 nbd_update_server_watch();
437 nbd_client_put(client);
440 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
443 if (state >= TERMINATE) {
448 nbd_update_server_watch();
449 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed);
452 static void nbd_update_server_watch(void)
454 if (nbd_can_accept()) {
455 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
457 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
462 static SocketAddress *nbd_build_socket_address(const char *sockpath,
466 SocketAddress *saddr;
468 saddr = g_new0(SocketAddress, 1);
470 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
471 saddr->u.q_unix.path = g_strdup(sockpath);
473 InetSocketAddress *inet;
474 saddr->type = SOCKET_ADDRESS_TYPE_INET;
475 inet = &saddr->u.inet;
476 inet->host = g_strdup(bindto);
478 inet->port = g_strdup(port);
480 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
488 static QemuOptsList file_opts = {
490 .implied_opt_name = "file",
491 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
493 /* no elements => accept any params */
494 { /* end of list */ }
498 static QemuOptsList qemu_object_opts = {
500 .implied_opt_name = "qom-type",
501 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
509 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
513 QCryptoTLSCreds *creds;
515 obj = object_resolve_path_component(
516 object_get_objects_root(), id);
518 error_setg(errp, "No TLS credentials with id '%s'",
522 creds = (QCryptoTLSCreds *)
523 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
525 error_setg(errp, "Object with id '%s' is not TLS credentials",
531 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
533 "Expecting TLS credentials with a client endpoint");
537 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
539 "Expecting TLS credentials with a server endpoint");
547 static void setup_address_and_port(const char **address, const char **port)
549 if (*address == NULL) {
550 *address = "0.0.0.0";
554 *port = stringify(NBD_DEFAULT_PORT);
559 * Check socket parameters compatibility when socket activation is used.
561 static const char *socket_activation_validate_opts(const char *device,
562 const char *sockpath,
567 if (device != NULL) {
568 return "NBD device can't be set when using socket activation";
571 if (sockpath != NULL) {
572 return "Unix socket can't be set when using socket activation";
575 if (address != NULL) {
576 return "The interface can't be set when using socket activation";
580 return "TCP port number can't be set when using socket activation";
584 return "List mode is incompatible with socket activation";
590 static void qemu_nbd_shutdown(void)
592 job_cancel_sync_all();
596 int main(int argc, char **argv)
599 BlockDriverState *bs;
600 uint64_t dev_offset = 0;
601 uint16_t nbdflags = 0;
602 bool disconnect = false;
603 const char *bindto = NULL;
604 const char *port = NULL;
605 char *sockpath = NULL;
608 QemuOpts *sn_opts = NULL;
609 const char *sn_id_or_name = NULL;
610 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:L";
611 struct option lopt[] = {
612 { "help", no_argument, NULL, 'h' },
613 { "version", no_argument, NULL, 'V' },
614 { "bind", required_argument, NULL, 'b' },
615 { "port", required_argument, NULL, 'p' },
616 { "socket", required_argument, NULL, 'k' },
617 { "offset", required_argument, NULL, 'o' },
618 { "read-only", no_argument, NULL, 'r' },
619 { "partition", required_argument, NULL, 'P' },
620 { "bitmap", required_argument, NULL, 'B' },
621 { "connect", required_argument, NULL, 'c' },
622 { "disconnect", no_argument, NULL, 'd' },
623 { "list", no_argument, NULL, 'L' },
624 { "snapshot", no_argument, NULL, 's' },
625 { "load-snapshot", required_argument, NULL, 'l' },
626 { "nocache", no_argument, NULL, 'n' },
627 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
628 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
629 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
630 { "detect-zeroes", required_argument, NULL,
631 QEMU_NBD_OPT_DETECT_ZEROES },
632 { "shared", required_argument, NULL, 'e' },
633 { "format", required_argument, NULL, 'f' },
634 { "persistent", no_argument, NULL, 't' },
635 { "verbose", no_argument, NULL, 'v' },
636 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
637 { "export-name", required_argument, NULL, 'x' },
638 { "description", required_argument, NULL, 'D' },
639 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
640 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ },
641 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
642 { "trace", required_argument, NULL, 'T' },
643 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
648 int flags = BDRV_O_RDWR;
651 bool seen_cache = false;
652 bool seen_discard = false;
653 bool seen_aio = false;
654 pthread_t client_thread;
655 const char *fmt = NULL;
656 Error *local_err = NULL;
657 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
658 QDict *options = NULL;
659 const char *export_name = NULL; /* defaults to "" later for server mode */
660 const char *export_description = NULL;
661 const char *bitmap = NULL;
662 const char *tlscredsid = NULL;
663 bool imageOpts = false;
664 bool writethrough = true;
665 char *trace_file = NULL;
666 bool fork_process = false;
669 unsigned socket_activation;
671 /* The client thread uses SIGTERM to interrupt the server. A signal
672 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
674 struct sigaction sa_sigterm;
675 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
676 sa_sigterm.sa_handler = termsig_handler;
677 sigaction(SIGTERM, &sa_sigterm, NULL);
680 signal(SIGPIPE, SIG_IGN);
684 module_call_init(MODULE_INIT_TRACE);
685 qcrypto_init(&error_fatal);
687 module_call_init(MODULE_INIT_QOM);
688 qemu_add_opts(&qemu_object_opts);
689 qemu_add_opts(&qemu_trace_opts);
690 qemu_init_exec_dir(argv[0]);
692 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
695 flags |= BDRV_O_SNAPSHOT;
698 optarg = (char *) "none";
700 case QEMU_NBD_OPT_CACHE:
702 error_report("-n and --cache can only be specified once");
706 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
707 error_report("Invalid cache mode `%s'", optarg);
711 case QEMU_NBD_OPT_AIO:
713 error_report("--aio can only be specified once");
717 if (!strcmp(optarg, "native")) {
718 flags |= BDRV_O_NATIVE_AIO;
719 } else if (!strcmp(optarg, "threads")) {
720 /* this is the default */
722 error_report("invalid aio mode `%s'", optarg);
726 case QEMU_NBD_OPT_DISCARD:
728 error_report("--discard can only be specified once");
732 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
733 error_report("Invalid discard mode `%s'", optarg);
737 case QEMU_NBD_OPT_DETECT_ZEROES:
739 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
741 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
744 error_reportf_err(local_err,
745 "Failed to parse detect_zeroes mode: ");
748 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
749 !(flags & BDRV_O_UNMAP)) {
750 error_report("setting detect-zeroes to unmap is not allowed "
751 "without setting discard operation to unmap");
762 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
763 error_report("Invalid offset '%s'", optarg);
768 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
769 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
772 error_report("Failed in parsing snapshot param `%s'",
777 sn_id_or_name = optarg;
781 nbdflags |= NBD_FLAG_READ_ONLY;
782 flags &= ~BDRV_O_RDWR;
785 warn_report("The '-P' option is deprecated; use --image-opts with "
786 "a raw device wrapper for subset exports instead");
787 if (qemu_strtoi(optarg, NULL, 0, &partition) < 0 ||
788 partition < 1 || partition > 8) {
789 error_report("Invalid partition '%s'", optarg);
798 if (sockpath[0] != '/') {
799 error_report("socket path must be absolute");
810 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
812 error_report("Invalid shared device number '%s'", optarg);
823 export_name = optarg;
826 export_description = optarg;
840 error_report("Try `%s --help' for more information.", argv[0]);
842 case QEMU_NBD_OPT_OBJECT: {
844 opts = qemu_opts_parse_noisily(&qemu_object_opts,
850 case QEMU_NBD_OPT_TLSCREDS:
853 case QEMU_NBD_OPT_IMAGE_OPTS:
858 trace_file = trace_opt_parse(optarg);
860 case QEMU_NBD_OPT_TLSAUTHZ:
863 case QEMU_NBD_OPT_FORK:
873 if (argc != optind) {
874 error_report("List mode is incompatible with a file name");
877 if (export_name || export_description || dev_offset || partition ||
878 device || disconnect || fmt || sn_id_or_name || bitmap ||
879 seen_aio || seen_discard || seen_cache) {
880 error_report("List mode is incompatible with per-device settings");
884 error_report("List mode is incompatible with forking");
887 } else if ((argc - optind) != 1) {
888 error_report("Invalid number of arguments");
889 error_printf("Try `%s --help' for more information.\n", argv[0]);
891 } else if (!export_name) {
895 qemu_opts_foreach(&qemu_object_opts,
896 user_creatable_add_opts_foreach,
899 if (!trace_init_backends()) {
902 trace_init_file(trace_file);
903 qemu_set_log(LOG_TRACE);
905 socket_activation = check_socket_activation();
906 if (socket_activation == 0) {
907 setup_address_and_port(&bindto, &port);
909 /* Using socket activation - check user didn't use -p etc. */
910 const char *err_msg = socket_activation_validate_opts(device, sockpath,
913 if (err_msg != NULL) {
914 error_report("%s", err_msg);
918 /* qemu-nbd can only listen on a single socket. */
919 if (socket_activation > 1) {
920 error_report("qemu-nbd does not support socket activation with %s > 1",
928 error_report("TLS is only supported with IPv4/IPv6");
932 error_report("TLS is not supported with a host device");
935 if (tlsauthz && list) {
936 error_report("TLS authorization is incompatible with export list");
939 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
941 error_report("Failed to get TLS creds %s",
942 error_get_pretty(local_err));
947 error_report("--tls-authz is not permitted without --tls-creds");
953 saddr = nbd_build_socket_address(sockpath, bindto, port);
954 return qemu_nbd_client_list(saddr, tlscreds, bindto);
958 if (disconnect || device) {
959 error_report("Kernel /dev/nbdN support not available");
962 #else /* HAVE_NBD_DEVICE */
964 int nbdfd = open(argv[optind], O_RDWR);
966 error_report("Cannot open %s: %s", argv[optind],
970 nbd_disconnect(nbdfd);
974 printf("%s disconnected\n", argv[optind]);
980 if ((device && !verbose) || fork_process) {
985 if (qemu_pipe(stderr_fd) < 0) {
986 error_report("Error setting up communication pipe: %s",
991 /* Now daemonize, but keep a communication channel open to
992 * print errors and exit with the proper status code.
996 error_report("Failed to fork: %s", strerror(errno));
998 } else if (pid == 0) {
1000 ret = qemu_daemon(1, 0);
1002 /* Temporarily redirect stderr to the parent's pipe... */
1003 old_stderr = dup(STDERR_FILENO);
1004 dup2(stderr_fd[1], STDERR_FILENO);
1006 error_report("Failed to daemonize: %s", strerror(errno));
1010 /* ... close the descriptor we inherited and go on. */
1011 close(stderr_fd[1]);
1013 bool errors = false;
1016 /* In the parent. Print error messages from the child until
1017 * it closes the pipe.
1019 close(stderr_fd[1]);
1020 buf = g_malloc(1024);
1021 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1023 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1029 error_report("Cannot read from daemon: %s",
1034 /* Usually the daemon should not print any message.
1035 * Exit with zero status in that case.
1041 if (device != NULL && sockpath == NULL) {
1042 sockpath = g_malloc(128);
1043 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
1046 server = qio_net_listener_new();
1047 if (socket_activation == 0) {
1048 saddr = nbd_build_socket_address(sockpath, bindto, port);
1049 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) {
1050 object_unref(OBJECT(server));
1051 error_report_err(local_err);
1056 /* See comment in check_socket_activation above. */
1057 for (i = 0; i < socket_activation; i++) {
1058 QIOChannelSocket *sioc;
1059 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1062 object_unref(OBJECT(server));
1063 error_report("Failed to use socket activation: %s",
1064 error_get_pretty(local_err));
1067 qio_net_listener_add(server, sioc);
1068 object_unref(OBJECT(sioc));
1072 if (qemu_init_main_loop(&local_err)) {
1073 error_report_err(local_err);
1077 atexit(qemu_nbd_shutdown);
1079 srcpath = argv[optind];
1083 error_report("--image-opts and -f are mutually exclusive");
1086 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1088 qemu_opts_reset(&file_opts);
1091 options = qemu_opts_to_qdict(opts, NULL);
1092 qemu_opts_reset(&file_opts);
1093 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1096 options = qdict_new();
1097 qdict_put_str(options, "driver", fmt);
1099 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1103 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1109 blk_set_enable_write_cache(blk, !writethrough);
1112 ret = bdrv_snapshot_load_tmp(bs,
1113 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1114 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1116 } else if (sn_id_or_name) {
1117 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1121 error_reportf_err(local_err, "Failed to load snapshot: ");
1125 bs->detect_zeroes = detect_zeroes;
1126 fd_size = blk_getlength(blk);
1128 error_report("Failed to determine the image length: %s",
1129 strerror(-fd_size));
1133 if (dev_offset >= fd_size) {
1134 error_report("Offset (%" PRIu64 ") has to be smaller than the image "
1135 "size (%" PRId64 ")", dev_offset, fd_size);
1138 fd_size -= dev_offset;
1144 error_report("Cannot request partition and offset together");
1147 ret = find_partition(blk, partition, &dev_offset, &limit);
1149 error_report("Could not find partition %d: %s", partition,
1154 * MBR partition limits are (32-bit << 9); this assert lets
1155 * the compiler know that we can't overflow 64 bits.
1157 assert(dev_offset + limit >= dev_offset);
1158 if (dev_offset + limit > fd_size) {
1159 error_report("Discovered partition %d at offset %" PRIu64
1160 " size %" PRIu64 ", but size exceeds file length %"
1161 PRId64, partition, dev_offset, limit, fd_size);
1167 export = nbd_export_new(bs, dev_offset, fd_size, export_name,
1168 export_description, bitmap, nbdflags,
1169 nbd_export_closed, writethrough, NULL,
1176 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1178 error_report("Failed to create client thread: %s", strerror(ret));
1183 /* Shut up GCC warnings. */
1184 memset(&client_thread, 0, sizeof(client_thread));
1187 nbd_update_server_watch();
1189 /* now when the initialization is (almost) complete, chdir("/")
1190 * to free any busy filesystems */
1191 if (chdir("/") < 0) {
1192 error_report("Could not chdir to root directory: %s",
1198 dup2(old_stderr, STDERR_FILENO);
1204 main_loop_wait(false);
1205 if (state == TERMINATE) {
1206 state = TERMINATING;
1207 nbd_export_close(export);
1208 nbd_export_put(export);
1211 } while (state != TERMINATED);
1218 qemu_opts_del(sn_opts);
1222 pthread_join(client_thread, &ret);