qcow2: Explicit number replaced by a constant
[qemu/ar7.git] / qemu-nbd.c
blob51b9d38c72732c821cb4ee5bf362533406ce2494
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 "qapi/error.h"
25 #include "qemu/cutils.h"
26 #include "sysemu/block-backend.h"
27 #include "block/block_int.h"
28 #include "block/nbd.h"
29 #include "qemu/main-loop.h"
30 #include "qemu/option.h"
31 #include "qemu/error-report.h"
32 #include "qemu/config-file.h"
33 #include "qemu/bswap.h"
34 #include "qemu/log.h"
35 #include "qemu/systemd.h"
36 #include "block/snapshot.h"
37 #include "qapi/qmp/qdict.h"
38 #include "qapi/qmp/qstring.h"
39 #include "qom/object_interfaces.h"
40 #include "io/channel-socket.h"
41 #include "io/net-listener.h"
42 #include "crypto/init.h"
43 #include "trace/control.h"
44 #include "qemu-version.h"
46 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
47 #define QEMU_NBD_OPT_CACHE 256
48 #define QEMU_NBD_OPT_AIO 257
49 #define QEMU_NBD_OPT_DISCARD 258
50 #define QEMU_NBD_OPT_DETECT_ZEROES 259
51 #define QEMU_NBD_OPT_OBJECT 260
52 #define QEMU_NBD_OPT_TLSCREDS 261
53 #define QEMU_NBD_OPT_IMAGE_OPTS 262
54 #define QEMU_NBD_OPT_FORK 263
56 #define MBR_SIZE 512
58 static NBDExport *exp;
59 static bool newproto;
60 static int verbose;
61 static char *srcpath;
62 static SocketAddress *saddr;
63 static int persistent = 0;
64 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
65 static int shared = 1;
66 static int nb_fds;
67 static QIONetListener *server;
68 static QCryptoTLSCreds *tlscreds;
70 static void usage(const char *name)
72 (printf) (
73 "Usage: %s [OPTIONS] FILE\n"
74 "QEMU Disk Network Block Device Server\n"
75 "\n"
76 " -h, --help display this help and exit\n"
77 " -V, --version output version information and exit\n"
78 "\n"
79 "Connection properties:\n"
80 " -p, --port=PORT port to listen on (default `%d')\n"
81 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
82 " -k, --socket=PATH path to the unix socket\n"
83 " (default '"SOCKET_PATH"')\n"
84 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
85 " -t, --persistent don't exit on the last connection\n"
86 " -v, --verbose display extra debugging information\n"
87 " -x, --export-name=NAME expose export by name\n"
88 " -D, --description=TEXT with -x, also export a human-readable description\n"
89 "\n"
90 "Exposing part of the image:\n"
91 " -o, --offset=OFFSET offset into the image\n"
92 " -P, --partition=NUM only expose partition NUM\n"
93 "\n"
94 "General purpose options:\n"
95 " --object type,id=ID,... define an object such as 'secret' for providing\n"
96 " passwords and/or encryption keys\n"
97 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
98 " specify tracing options\n"
99 " --fork fork off the server process and exit the parent\n"
100 " once the server is running\n"
101 #ifdef __linux__
102 "Kernel NBD client support:\n"
103 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
104 " -d, --disconnect disconnect the specified device\n"
105 "\n"
106 #endif
107 "\n"
108 "Block device options:\n"
109 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
110 " -r, --read-only export read-only\n"
111 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
112 " file with backing_file=FILE, redirect the write to\n"
113 " the temporary one\n"
114 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
115 " load an internal snapshot inside FILE and export it\n"
116 " as an read-only device, SNAPSHOT_PARAM format is\n"
117 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
118 " '[ID_OR_NAME]'\n"
119 " -n, --nocache disable host cache\n"
120 " --cache=MODE set cache mode (none, writeback, ...)\n"
121 " --aio=MODE set AIO mode (native or threads)\n"
122 " --discard=MODE set discard mode (ignore, unmap)\n"
123 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
124 " --image-opts treat FILE as a full set of image options\n"
125 "\n"
126 QEMU_HELP_BOTTOM "\n"
127 , name, NBD_DEFAULT_PORT, "DEVICE");
130 static void version(const char *name)
132 printf(
133 "%s " QEMU_FULL_VERSION "\n"
134 "Written by Anthony Liguori.\n"
135 "\n"
136 QEMU_COPYRIGHT "\n"
137 "This is free software; see the source for copying conditions. There is NO\n"
138 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
139 , name);
142 struct partition_record
144 uint8_t bootable;
145 uint8_t start_head;
146 uint32_t start_cylinder;
147 uint8_t start_sector;
148 uint8_t system;
149 uint8_t end_head;
150 uint8_t end_cylinder;
151 uint8_t end_sector;
152 uint32_t start_sector_abs;
153 uint32_t nb_sectors_abs;
156 static void read_partition(uint8_t *p, struct partition_record *r)
158 r->bootable = p[0];
159 r->start_head = p[1];
160 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
161 r->start_sector = p[2] & 0x3f;
162 r->system = p[4];
163 r->end_head = p[5];
164 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
165 r->end_sector = p[6] & 0x3f;
167 r->start_sector_abs = ldl_le_p(p + 8);
168 r->nb_sectors_abs = ldl_le_p(p + 12);
171 static int find_partition(BlockBackend *blk, int partition,
172 off_t *offset, off_t *size)
174 struct partition_record mbr[4];
175 uint8_t data[MBR_SIZE];
176 int i;
177 int ext_partnum = 4;
178 int ret;
180 ret = blk_pread(blk, 0, data, sizeof(data));
181 if (ret < 0) {
182 error_report("error while reading: %s", strerror(-ret));
183 exit(EXIT_FAILURE);
186 if (data[510] != 0x55 || data[511] != 0xaa) {
187 return -EINVAL;
190 for (i = 0; i < 4; i++) {
191 read_partition(&data[446 + 16 * i], &mbr[i]);
193 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
194 continue;
197 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
198 struct partition_record ext[4];
199 uint8_t data1[MBR_SIZE];
200 int j;
202 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE,
203 data1, sizeof(data1));
204 if (ret < 0) {
205 error_report("error while reading: %s", strerror(-ret));
206 exit(EXIT_FAILURE);
209 for (j = 0; j < 4; j++) {
210 read_partition(&data1[446 + 16 * j], &ext[j]);
211 if (!ext[j].system || !ext[j].nb_sectors_abs) {
212 continue;
215 if ((ext_partnum + j + 1) == partition) {
216 *offset = (uint64_t)ext[j].start_sector_abs << 9;
217 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
218 return 0;
221 ext_partnum += 4;
222 } else if ((i + 1) == partition) {
223 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
224 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
225 return 0;
229 return -ENOENT;
232 static void termsig_handler(int signum)
234 atomic_cmpxchg(&state, RUNNING, TERMINATE);
235 qemu_notify_event();
239 static void *show_parts(void *arg)
241 char *device = arg;
242 int nbd;
244 /* linux just needs an open() to trigger
245 * the partition table update
246 * but remember to load the module with max_part != 0 :
247 * modprobe nbd max_part=63
249 nbd = open(device, O_RDWR);
250 if (nbd >= 0) {
251 close(nbd);
253 return NULL;
256 static void *nbd_client_thread(void *arg)
258 char *device = arg;
259 NBDExportInfo info = { .request_sizes = false, };
260 QIOChannelSocket *sioc;
261 int fd;
262 int ret;
263 pthread_t show_parts_thread;
264 Error *local_error = NULL;
266 sioc = qio_channel_socket_new();
267 if (qio_channel_socket_connect_sync(sioc,
268 saddr,
269 &local_error) < 0) {
270 error_report_err(local_error);
271 goto out;
274 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL,
275 NULL, NULL, NULL, &info, &local_error);
276 if (ret < 0) {
277 if (local_error) {
278 error_report_err(local_error);
280 goto out_socket;
283 fd = open(device, O_RDWR);
284 if (fd < 0) {
285 /* Linux-only, we can use %m in printf. */
286 error_report("Failed to open %s: %m", device);
287 goto out_socket;
290 ret = nbd_init(fd, sioc, &info, &local_error);
291 if (ret < 0) {
292 error_report_err(local_error);
293 goto out_fd;
296 /* update partition table */
297 pthread_create(&show_parts_thread, NULL, show_parts, device);
299 if (verbose) {
300 fprintf(stderr, "NBD device %s is now connected to %s\n",
301 device, srcpath);
302 } else {
303 /* Close stderr so that the qemu-nbd process exits. */
304 dup2(STDOUT_FILENO, STDERR_FILENO);
307 ret = nbd_client(fd);
308 if (ret) {
309 goto out_fd;
311 close(fd);
312 object_unref(OBJECT(sioc));
313 kill(getpid(), SIGTERM);
314 return (void *) EXIT_SUCCESS;
316 out_fd:
317 close(fd);
318 out_socket:
319 object_unref(OBJECT(sioc));
320 out:
321 kill(getpid(), SIGTERM);
322 return (void *) EXIT_FAILURE;
325 static int nbd_can_accept(void)
327 return state == RUNNING && nb_fds < shared;
330 static void nbd_export_closed(NBDExport *exp)
332 assert(state == TERMINATING);
333 state = TERMINATED;
336 static void nbd_update_server_watch(void);
338 static void nbd_client_closed(NBDClient *client, bool negotiated)
340 nb_fds--;
341 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
342 state = TERMINATE;
344 nbd_update_server_watch();
345 nbd_client_put(client);
348 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
349 gpointer opaque)
351 if (state >= TERMINATE) {
352 return;
355 nb_fds++;
356 nbd_update_server_watch();
357 nbd_client_new(newproto ? NULL : exp, cioc,
358 tlscreds, NULL, nbd_client_closed);
361 static void nbd_update_server_watch(void)
363 if (nbd_can_accept()) {
364 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
365 } else {
366 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
371 static SocketAddress *nbd_build_socket_address(const char *sockpath,
372 const char *bindto,
373 const char *port)
375 SocketAddress *saddr;
377 saddr = g_new0(SocketAddress, 1);
378 if (sockpath) {
379 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
380 saddr->u.q_unix.path = g_strdup(sockpath);
381 } else {
382 InetSocketAddress *inet;
383 saddr->type = SOCKET_ADDRESS_TYPE_INET;
384 inet = &saddr->u.inet;
385 inet->host = g_strdup(bindto);
386 if (port) {
387 inet->port = g_strdup(port);
388 } else {
389 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
393 return saddr;
397 static QemuOptsList file_opts = {
398 .name = "file",
399 .implied_opt_name = "file",
400 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
401 .desc = {
402 /* no elements => accept any params */
403 { /* end of list */ }
407 static QemuOptsList qemu_object_opts = {
408 .name = "object",
409 .implied_opt_name = "qom-type",
410 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
411 .desc = {
418 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
420 Object *obj;
421 QCryptoTLSCreds *creds;
423 obj = object_resolve_path_component(
424 object_get_objects_root(), id);
425 if (!obj) {
426 error_setg(errp, "No TLS credentials with id '%s'",
427 id);
428 return NULL;
430 creds = (QCryptoTLSCreds *)
431 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
432 if (!creds) {
433 error_setg(errp, "Object with id '%s' is not TLS credentials",
434 id);
435 return NULL;
438 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
439 error_setg(errp,
440 "Expecting TLS credentials with a server endpoint");
441 return NULL;
443 object_ref(obj);
444 return creds;
447 static void setup_address_and_port(const char **address, const char **port)
449 if (*address == NULL) {
450 *address = "0.0.0.0";
453 if (*port == NULL) {
454 *port = stringify(NBD_DEFAULT_PORT);
459 * Check socket parameters compatibility when socket activation is used.
461 static const char *socket_activation_validate_opts(const char *device,
462 const char *sockpath,
463 const char *address,
464 const char *port)
466 if (device != NULL) {
467 return "NBD device can't be set when using socket activation";
470 if (sockpath != NULL) {
471 return "Unix socket can't be set when using socket activation";
474 if (address != NULL) {
475 return "The interface can't be set when using socket activation";
478 if (port != NULL) {
479 return "TCP port number can't be set when using socket activation";
482 return NULL;
485 static void qemu_nbd_shutdown(void)
487 job_cancel_sync_all();
488 bdrv_close_all();
491 int main(int argc, char **argv)
493 BlockBackend *blk;
494 BlockDriverState *bs;
495 off_t dev_offset = 0;
496 uint16_t nbdflags = 0;
497 bool disconnect = false;
498 const char *bindto = NULL;
499 const char *port = NULL;
500 char *sockpath = NULL;
501 char *device = NULL;
502 off_t fd_size;
503 QemuOpts *sn_opts = NULL;
504 const char *sn_id_or_name = NULL;
505 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:";
506 struct option lopt[] = {
507 { "help", no_argument, NULL, 'h' },
508 { "version", no_argument, NULL, 'V' },
509 { "bind", required_argument, NULL, 'b' },
510 { "port", required_argument, NULL, 'p' },
511 { "socket", required_argument, NULL, 'k' },
512 { "offset", required_argument, NULL, 'o' },
513 { "read-only", no_argument, NULL, 'r' },
514 { "partition", required_argument, NULL, 'P' },
515 { "connect", required_argument, NULL, 'c' },
516 { "disconnect", no_argument, NULL, 'd' },
517 { "snapshot", no_argument, NULL, 's' },
518 { "load-snapshot", required_argument, NULL, 'l' },
519 { "nocache", no_argument, NULL, 'n' },
520 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
521 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
522 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
523 { "detect-zeroes", required_argument, NULL,
524 QEMU_NBD_OPT_DETECT_ZEROES },
525 { "shared", required_argument, NULL, 'e' },
526 { "format", required_argument, NULL, 'f' },
527 { "persistent", no_argument, NULL, 't' },
528 { "verbose", no_argument, NULL, 'v' },
529 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
530 { "export-name", required_argument, NULL, 'x' },
531 { "description", required_argument, NULL, 'D' },
532 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
533 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
534 { "trace", required_argument, NULL, 'T' },
535 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
536 { NULL, 0, NULL, 0 }
538 int ch;
539 int opt_ind = 0;
540 char *end;
541 int flags = BDRV_O_RDWR;
542 int partition = -1;
543 int ret = 0;
544 bool seen_cache = false;
545 bool seen_discard = false;
546 bool seen_aio = false;
547 pthread_t client_thread;
548 const char *fmt = NULL;
549 Error *local_err = NULL;
550 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
551 QDict *options = NULL;
552 const char *export_name = NULL;
553 const char *export_description = NULL;
554 const char *tlscredsid = NULL;
555 bool imageOpts = false;
556 bool writethrough = true;
557 char *trace_file = NULL;
558 bool fork_process = false;
559 int old_stderr = -1;
560 unsigned socket_activation;
562 /* The client thread uses SIGTERM to interrupt the server. A signal
563 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
565 struct sigaction sa_sigterm;
566 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
567 sa_sigterm.sa_handler = termsig_handler;
568 sigaction(SIGTERM, &sa_sigterm, NULL);
570 #ifdef CONFIG_POSIX
571 signal(SIGPIPE, SIG_IGN);
572 #endif
574 module_call_init(MODULE_INIT_TRACE);
575 qcrypto_init(&error_fatal);
577 module_call_init(MODULE_INIT_QOM);
578 qemu_add_opts(&qemu_object_opts);
579 qemu_add_opts(&qemu_trace_opts);
580 qemu_init_exec_dir(argv[0]);
582 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
583 switch (ch) {
584 case 's':
585 flags |= BDRV_O_SNAPSHOT;
586 break;
587 case 'n':
588 optarg = (char *) "none";
589 /* fallthrough */
590 case QEMU_NBD_OPT_CACHE:
591 if (seen_cache) {
592 error_report("-n and --cache can only be specified once");
593 exit(EXIT_FAILURE);
595 seen_cache = true;
596 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
597 error_report("Invalid cache mode `%s'", optarg);
598 exit(EXIT_FAILURE);
600 break;
601 case QEMU_NBD_OPT_AIO:
602 if (seen_aio) {
603 error_report("--aio can only be specified once");
604 exit(EXIT_FAILURE);
606 seen_aio = true;
607 if (!strcmp(optarg, "native")) {
608 flags |= BDRV_O_NATIVE_AIO;
609 } else if (!strcmp(optarg, "threads")) {
610 /* this is the default */
611 } else {
612 error_report("invalid aio mode `%s'", optarg);
613 exit(EXIT_FAILURE);
615 break;
616 case QEMU_NBD_OPT_DISCARD:
617 if (seen_discard) {
618 error_report("--discard can only be specified once");
619 exit(EXIT_FAILURE);
621 seen_discard = true;
622 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
623 error_report("Invalid discard mode `%s'", optarg);
624 exit(EXIT_FAILURE);
626 break;
627 case QEMU_NBD_OPT_DETECT_ZEROES:
628 detect_zeroes =
629 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
630 optarg,
631 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
632 &local_err);
633 if (local_err) {
634 error_reportf_err(local_err,
635 "Failed to parse detect_zeroes mode: ");
636 exit(EXIT_FAILURE);
638 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
639 !(flags & BDRV_O_UNMAP)) {
640 error_report("setting detect-zeroes to unmap is not allowed "
641 "without setting discard operation to unmap");
642 exit(EXIT_FAILURE);
644 break;
645 case 'b':
646 bindto = optarg;
647 break;
648 case 'p':
649 port = optarg;
650 break;
651 case 'o':
652 dev_offset = strtoll (optarg, &end, 0);
653 if (*end) {
654 error_report("Invalid offset `%s'", optarg);
655 exit(EXIT_FAILURE);
657 if (dev_offset < 0) {
658 error_report("Offset must be positive `%s'", optarg);
659 exit(EXIT_FAILURE);
661 break;
662 case 'l':
663 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
664 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
665 optarg, false);
666 if (!sn_opts) {
667 error_report("Failed in parsing snapshot param `%s'",
668 optarg);
669 exit(EXIT_FAILURE);
671 } else {
672 sn_id_or_name = optarg;
674 /* fall through */
675 case 'r':
676 nbdflags |= NBD_FLAG_READ_ONLY;
677 flags &= ~BDRV_O_RDWR;
678 break;
679 case 'P':
680 partition = strtol(optarg, &end, 0);
681 if (*end) {
682 error_report("Invalid partition `%s'", optarg);
683 exit(EXIT_FAILURE);
685 if (partition < 1 || partition > 8) {
686 error_report("Invalid partition %d", partition);
687 exit(EXIT_FAILURE);
689 break;
690 case 'k':
691 sockpath = optarg;
692 if (sockpath[0] != '/') {
693 error_report("socket path must be absolute");
694 exit(EXIT_FAILURE);
696 break;
697 case 'd':
698 disconnect = true;
699 break;
700 case 'c':
701 device = optarg;
702 break;
703 case 'e':
704 shared = strtol(optarg, &end, 0);
705 if (*end) {
706 error_report("Invalid shared device number '%s'", optarg);
707 exit(EXIT_FAILURE);
709 if (shared < 1) {
710 error_report("Shared device number must be greater than 0");
711 exit(EXIT_FAILURE);
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 break;
723 case 'D':
724 export_description = optarg;
725 break;
726 case 'v':
727 verbose = 1;
728 break;
729 case 'V':
730 version(argv[0]);
731 exit(0);
732 break;
733 case 'h':
734 usage(argv[0]);
735 exit(0);
736 break;
737 case '?':
738 error_report("Try `%s --help' for more information.", argv[0]);
739 exit(EXIT_FAILURE);
740 case QEMU_NBD_OPT_OBJECT: {
741 QemuOpts *opts;
742 opts = qemu_opts_parse_noisily(&qemu_object_opts,
743 optarg, true);
744 if (!opts) {
745 exit(EXIT_FAILURE);
747 } break;
748 case QEMU_NBD_OPT_TLSCREDS:
749 tlscredsid = optarg;
750 break;
751 case QEMU_NBD_OPT_IMAGE_OPTS:
752 imageOpts = true;
753 break;
754 case 'T':
755 g_free(trace_file);
756 trace_file = trace_opt_parse(optarg);
757 break;
758 case QEMU_NBD_OPT_FORK:
759 fork_process = true;
760 break;
764 if ((argc - optind) != 1) {
765 error_report("Invalid number of arguments");
766 error_printf("Try `%s --help' for more information.\n", argv[0]);
767 exit(EXIT_FAILURE);
770 if (qemu_opts_foreach(&qemu_object_opts,
771 user_creatable_add_opts_foreach,
772 NULL, NULL)) {
773 exit(EXIT_FAILURE);
776 if (!trace_init_backends()) {
777 exit(1);
779 trace_init_file(trace_file);
780 qemu_set_log(LOG_TRACE);
782 socket_activation = check_socket_activation();
783 if (socket_activation == 0) {
784 setup_address_and_port(&bindto, &port);
785 } else {
786 /* Using socket activation - check user didn't use -p etc. */
787 const char *err_msg = socket_activation_validate_opts(device, sockpath,
788 bindto, port);
789 if (err_msg != NULL) {
790 error_report("%s", err_msg);
791 exit(EXIT_FAILURE);
794 /* qemu-nbd can only listen on a single socket. */
795 if (socket_activation > 1) {
796 error_report("qemu-nbd does not support socket activation with %s > 1",
797 "LISTEN_FDS");
798 exit(EXIT_FAILURE);
802 if (tlscredsid) {
803 if (sockpath) {
804 error_report("TLS is only supported with IPv4/IPv6");
805 exit(EXIT_FAILURE);
807 if (device) {
808 error_report("TLS is not supported with a host device");
809 exit(EXIT_FAILURE);
811 if (!export_name) {
812 /* Set the default NBD protocol export name, since
813 * we *must* use new style protocol for TLS */
814 export_name = "";
816 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err);
817 if (local_err) {
818 error_report("Failed to get TLS creds %s",
819 error_get_pretty(local_err));
820 exit(EXIT_FAILURE);
824 if (disconnect) {
825 int nbdfd = open(argv[optind], O_RDWR);
826 if (nbdfd < 0) {
827 error_report("Cannot open %s: %s", argv[optind],
828 strerror(errno));
829 exit(EXIT_FAILURE);
831 nbd_disconnect(nbdfd);
833 close(nbdfd);
835 printf("%s disconnected\n", argv[optind]);
837 return 0;
840 if ((device && !verbose) || fork_process) {
841 int stderr_fd[2];
842 pid_t pid;
843 int ret;
845 if (qemu_pipe(stderr_fd) < 0) {
846 error_report("Error setting up communication pipe: %s",
847 strerror(errno));
848 exit(EXIT_FAILURE);
851 /* Now daemonize, but keep a communication channel open to
852 * print errors and exit with the proper status code.
854 pid = fork();
855 if (pid < 0) {
856 error_report("Failed to fork: %s", strerror(errno));
857 exit(EXIT_FAILURE);
858 } else if (pid == 0) {
859 close(stderr_fd[0]);
860 ret = qemu_daemon(1, 0);
862 /* Temporarily redirect stderr to the parent's pipe... */
863 old_stderr = dup(STDERR_FILENO);
864 dup2(stderr_fd[1], STDERR_FILENO);
865 if (ret < 0) {
866 error_report("Failed to daemonize: %s", strerror(errno));
867 exit(EXIT_FAILURE);
870 /* ... close the descriptor we inherited and go on. */
871 close(stderr_fd[1]);
872 } else {
873 bool errors = false;
874 char *buf;
876 /* In the parent. Print error messages from the child until
877 * it closes the pipe.
879 close(stderr_fd[1]);
880 buf = g_malloc(1024);
881 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
882 errors = true;
883 ret = qemu_write_full(STDERR_FILENO, buf, ret);
884 if (ret < 0) {
885 exit(EXIT_FAILURE);
888 if (ret < 0) {
889 error_report("Cannot read from daemon: %s",
890 strerror(errno));
891 exit(EXIT_FAILURE);
894 /* Usually the daemon should not print any message.
895 * Exit with zero status in that case.
897 exit(errors);
901 if (device != NULL && sockpath == NULL) {
902 sockpath = g_malloc(128);
903 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
906 server = qio_net_listener_new();
907 if (socket_activation == 0) {
908 saddr = nbd_build_socket_address(sockpath, bindto, port);
909 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) {
910 object_unref(OBJECT(server));
911 error_report_err(local_err);
912 exit(EXIT_FAILURE);
914 } else {
915 size_t i;
916 /* See comment in check_socket_activation above. */
917 for (i = 0; i < socket_activation; i++) {
918 QIOChannelSocket *sioc;
919 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
920 &local_err);
921 if (sioc == NULL) {
922 object_unref(OBJECT(server));
923 error_report("Failed to use socket activation: %s",
924 error_get_pretty(local_err));
925 exit(EXIT_FAILURE);
927 qio_net_listener_add(server, sioc);
928 object_unref(OBJECT(sioc));
932 if (qemu_init_main_loop(&local_err)) {
933 error_report_err(local_err);
934 exit(EXIT_FAILURE);
936 bdrv_init();
937 atexit(qemu_nbd_shutdown);
939 srcpath = argv[optind];
940 if (imageOpts) {
941 QemuOpts *opts;
942 if (fmt) {
943 error_report("--image-opts and -f are mutually exclusive");
944 exit(EXIT_FAILURE);
946 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
947 if (!opts) {
948 qemu_opts_reset(&file_opts);
949 exit(EXIT_FAILURE);
951 options = qemu_opts_to_qdict(opts, NULL);
952 qemu_opts_reset(&file_opts);
953 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
954 } else {
955 if (fmt) {
956 options = qdict_new();
957 qdict_put_str(options, "driver", fmt);
959 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
962 if (!blk) {
963 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
964 argv[optind]);
965 exit(EXIT_FAILURE);
967 bs = blk_bs(blk);
969 blk_set_enable_write_cache(blk, !writethrough);
971 if (sn_opts) {
972 ret = bdrv_snapshot_load_tmp(bs,
973 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
974 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
975 &local_err);
976 } else if (sn_id_or_name) {
977 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
978 &local_err);
980 if (ret < 0) {
981 error_reportf_err(local_err, "Failed to load snapshot: ");
982 exit(EXIT_FAILURE);
985 bs->detect_zeroes = detect_zeroes;
986 fd_size = blk_getlength(blk);
987 if (fd_size < 0) {
988 error_report("Failed to determine the image length: %s",
989 strerror(-fd_size));
990 exit(EXIT_FAILURE);
993 if (dev_offset >= fd_size) {
994 error_report("Offset (%lld) has to be smaller than the image size "
995 "(%lld)",
996 (long long int)dev_offset, (long long int)fd_size);
997 exit(EXIT_FAILURE);
999 fd_size -= dev_offset;
1001 if (partition != -1) {
1002 ret = find_partition(blk, partition, &dev_offset, &fd_size);
1003 if (ret < 0) {
1004 error_report("Could not find partition %d: %s", partition,
1005 strerror(-ret));
1006 exit(EXIT_FAILURE);
1010 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed,
1011 writethrough, NULL, &local_err);
1012 if (!exp) {
1013 error_report_err(local_err);
1014 exit(EXIT_FAILURE);
1016 if (export_name) {
1017 nbd_export_set_name(exp, export_name);
1018 nbd_export_set_description(exp, export_description);
1019 newproto = true;
1020 } else if (export_description) {
1021 error_report("Export description requires an export name");
1022 exit(EXIT_FAILURE);
1025 if (device) {
1026 int ret;
1028 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1029 if (ret != 0) {
1030 error_report("Failed to create client thread: %s", strerror(ret));
1031 exit(EXIT_FAILURE);
1033 } else {
1034 /* Shut up GCC warnings. */
1035 memset(&client_thread, 0, sizeof(client_thread));
1038 nbd_update_server_watch();
1040 /* now when the initialization is (almost) complete, chdir("/")
1041 * to free any busy filesystems */
1042 if (chdir("/") < 0) {
1043 error_report("Could not chdir to root directory: %s",
1044 strerror(errno));
1045 exit(EXIT_FAILURE);
1048 if (fork_process) {
1049 dup2(old_stderr, STDERR_FILENO);
1050 close(old_stderr);
1053 state = RUNNING;
1054 do {
1055 main_loop_wait(false);
1056 if (state == TERMINATE) {
1057 state = TERMINATING;
1058 nbd_export_close(exp);
1059 nbd_export_put(exp);
1060 exp = NULL;
1062 } while (state != TERMINATED);
1064 blk_unref(blk);
1065 if (sockpath) {
1066 unlink(sockpath);
1069 qemu_opts_del(sn_opts);
1071 if (device) {
1072 void *ret;
1073 pthread_join(client_thread, &ret);
1074 exit(ret != NULL);
1075 } else {
1076 exit(EXIT_SUCCESS);