hw/net: fix mcf_fec driver receiver
[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-common.h"
20 #include "sysemu/block-backend.h"
21 #include "block/block_int.h"
22 #include "block/nbd.h"
23 #include "qemu/main-loop.h"
24 #include "qemu/sockets.h"
25 #include "qemu/error-report.h"
26 #include "block/snapshot.h"
27 #include "qapi/util.h"
28 #include "qapi/qmp/qstring.h"
29
30 #include <stdarg.h>
31 #include <stdio.h>
32 #include <getopt.h>
33 #include <err.h>
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <netinet/in.h>
37 #include <netinet/tcp.h>
38 #include <arpa/inet.h>
39 #include <signal.h>
40 #include <libgen.h>
41 #include <pthread.h>
42
43 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
44 #define QEMU_NBD_OPT_CACHE 1
45 #define QEMU_NBD_OPT_AIO 2
46 #define QEMU_NBD_OPT_DISCARD 3
47 #define QEMU_NBD_OPT_DETECT_ZEROES 4
48
49 static NBDExport *exp;
50 static int verbose;
51 static char *srcpath;
52 static char *sockpath;
53 static int persistent = 0;
54 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
55 static int shared = 1;
56 static int nb_fds;
57 static int server_fd;
58
59 static void usage(const char *name)
60 {
61 (printf) (
62 "Usage: %s [OPTIONS] FILE\n"
63 "QEMU Disk Network Block Device Server\n"
64 "\n"
65 " -h, --help display this help and exit\n"
66 " -V, --version output version information and exit\n"
67 "\n"
68 "Connection properties:\n"
69 " -p, --port=PORT port to listen on (default `%d')\n"
70 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
71 " -k, --socket=PATH path to the unix socket\n"
72 " (default '"SOCKET_PATH"')\n"
73 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
74 " -t, --persistent don't exit on the last connection\n"
75 " -v, --verbose display extra debugging information\n"
76 "\n"
77 "Exposing part of the image:\n"
78 " -o, --offset=OFFSET offset into the image\n"
79 " -P, --partition=NUM only expose partition NUM\n"
80 "\n"
81 #ifdef __linux__
82 "Kernel NBD client support:\n"
83 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
84 " -d, --disconnect disconnect the specified device\n"
85 "\n"
86 #endif
87 "\n"
88 "Block device options:\n"
89 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
90 " -r, --read-only export read-only\n"
91 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
92 " file with backing_file=FILE, redirect the write to\n"
93 " the temporary one\n"
94 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
95 " load an internal snapshot inside FILE and export it\n"
96 " as an read-only device, SNAPSHOT_PARAM format is\n"
97 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
98 " '[ID_OR_NAME]'\n"
99 " -n, --nocache disable host cache\n"
100 " --cache=MODE set cache mode (none, writeback, ...)\n"
101 #ifdef CONFIG_LINUX_AIO
102 " --aio=MODE set AIO mode (native or threads)\n"
103 #endif
104 " --discard=MODE set discard mode (ignore, unmap)\n"
105 " --detect-zeroes=MODE set detect-zeroes mode (off, on, discard)\n"
106 "\n"
107 "Report bugs to <qemu-devel@nongnu.org>\n"
108 , name, NBD_DEFAULT_PORT, "DEVICE");
109 }
110
111 static void version(const char *name)
112 {
113 printf(
114 "%s version 0.0.1\n"
115 "Written by Anthony Liguori.\n"
116 "\n"
117 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n"
118 "This is free software; see the source for copying conditions. There is NO\n"
119 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
120 , name);
121 }
122
123 struct partition_record
124 {
125 uint8_t bootable;
126 uint8_t start_head;
127 uint32_t start_cylinder;
128 uint8_t start_sector;
129 uint8_t system;
130 uint8_t end_head;
131 uint8_t end_cylinder;
132 uint8_t end_sector;
133 uint32_t start_sector_abs;
134 uint32_t nb_sectors_abs;
135 };
136
137 static void read_partition(uint8_t *p, struct partition_record *r)
138 {
139 r->bootable = p[0];
140 r->start_head = p[1];
141 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
142 r->start_sector = p[2] & 0x3f;
143 r->system = p[4];
144 r->end_head = p[5];
145 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
146 r->end_sector = p[6] & 0x3f;
147
148 r->start_sector_abs = le32_to_cpup((uint32_t *)(p + 8));
149 r->nb_sectors_abs = le32_to_cpup((uint32_t *)(p + 12));
150 }
151
152 static int find_partition(BlockBackend *blk, int partition,
153 off_t *offset, off_t *size)
154 {
155 struct partition_record mbr[4];
156 uint8_t data[512];
157 int i;
158 int ext_partnum = 4;
159 int ret;
160
161 if ((ret = blk_read(blk, 0, data, 1)) < 0) {
162 errno = -ret;
163 err(EXIT_FAILURE, "error while reading");
164 }
165
166 if (data[510] != 0x55 || data[511] != 0xaa) {
167 return -EINVAL;
168 }
169
170 for (i = 0; i < 4; i++) {
171 read_partition(&data[446 + 16 * i], &mbr[i]);
172
173 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
174 continue;
175 }
176
177 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
178 struct partition_record ext[4];
179 uint8_t data1[512];
180 int j;
181
182 if ((ret = blk_read(blk, mbr[i].start_sector_abs, data1, 1)) < 0) {
183 errno = -ret;
184 err(EXIT_FAILURE, "error while reading");
185 }
186
187 for (j = 0; j < 4; j++) {
188 read_partition(&data1[446 + 16 * j], &ext[j]);
189 if (!ext[j].system || !ext[j].nb_sectors_abs) {
190 continue;
191 }
192
193 if ((ext_partnum + j + 1) == partition) {
194 *offset = (uint64_t)ext[j].start_sector_abs << 9;
195 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
196 return 0;
197 }
198 }
199 ext_partnum += 4;
200 } else if ((i + 1) == partition) {
201 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
202 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
203 return 0;
204 }
205 }
206
207 return -ENOENT;
208 }
209
210 static void termsig_handler(int signum)
211 {
212 state = TERMINATE;
213 qemu_notify_event();
214 }
215
216 static void combine_addr(char *buf, size_t len, const char* address,
217 uint16_t port)
218 {
219 /* If the address-part contains a colon, it's an IPv6 IP so needs [] */
220 if (strstr(address, ":")) {
221 snprintf(buf, len, "[%s]:%u", address, port);
222 } else {
223 snprintf(buf, len, "%s:%u", address, port);
224 }
225 }
226
227 static int tcp_socket_incoming(const char *address, uint16_t port)
228 {
229 char address_and_port[128];
230 Error *local_err = NULL;
231
232 combine_addr(address_and_port, 128, address, port);
233 int fd = inet_listen(address_and_port, NULL, 0, SOCK_STREAM, 0, &local_err);
234
235 if (local_err != NULL) {
236 error_report_err(local_err);
237 }
238 return fd;
239 }
240
241 static int unix_socket_incoming(const char *path)
242 {
243 Error *local_err = NULL;
244 int fd = unix_listen(path, NULL, 0, &local_err);
245
246 if (local_err != NULL) {
247 error_report_err(local_err);
248 }
249 return fd;
250 }
251
252 static int unix_socket_outgoing(const char *path)
253 {
254 Error *local_err = NULL;
255 int fd = unix_connect(path, &local_err);
256
257 if (local_err != NULL) {
258 error_report_err(local_err);
259 }
260 return fd;
261 }
262
263 static void *show_parts(void *arg)
264 {
265 char *device = arg;
266 int nbd;
267
268 /* linux just needs an open() to trigger
269 * the partition table update
270 * but remember to load the module with max_part != 0 :
271 * modprobe nbd max_part=63
272 */
273 nbd = open(device, O_RDWR);
274 if (nbd >= 0) {
275 close(nbd);
276 }
277 return NULL;
278 }
279
280 static void *nbd_client_thread(void *arg)
281 {
282 char *device = arg;
283 off_t size;
284 uint32_t nbdflags;
285 int fd, sock;
286 int ret;
287 pthread_t show_parts_thread;
288 Error *local_error = NULL;
289
290 sock = unix_socket_outgoing(sockpath);
291 if (sock < 0) {
292 goto out;
293 }
294
295 ret = nbd_receive_negotiate(sock, NULL, &nbdflags,
296 &size, &local_error);
297 if (ret < 0) {
298 if (local_error) {
299 fprintf(stderr, "%s\n", error_get_pretty(local_error));
300 error_free(local_error);
301 }
302 goto out_socket;
303 }
304
305 fd = open(device, O_RDWR);
306 if (fd < 0) {
307 /* Linux-only, we can use %m in printf. */
308 fprintf(stderr, "Failed to open %s: %m\n", device);
309 goto out_socket;
310 }
311
312 ret = nbd_init(fd, sock, nbdflags, size);
313 if (ret < 0) {
314 goto out_fd;
315 }
316
317 /* update partition table */
318 pthread_create(&show_parts_thread, NULL, show_parts, device);
319
320 if (verbose) {
321 fprintf(stderr, "NBD device %s is now connected to %s\n",
322 device, srcpath);
323 } else {
324 /* Close stderr so that the qemu-nbd process exits. */
325 dup2(STDOUT_FILENO, STDERR_FILENO);
326 }
327
328 ret = nbd_client(fd);
329 if (ret) {
330 goto out_fd;
331 }
332 close(fd);
333 kill(getpid(), SIGTERM);
334 return (void *) EXIT_SUCCESS;
335
336 out_fd:
337 close(fd);
338 out_socket:
339 closesocket(sock);
340 out:
341 kill(getpid(), SIGTERM);
342 return (void *) EXIT_FAILURE;
343 }
344
345 static int nbd_can_accept(void)
346 {
347 return nb_fds < shared;
348 }
349
350 static void nbd_export_closed(NBDExport *exp)
351 {
352 assert(state == TERMINATING);
353 state = TERMINATED;
354 }
355
356 static void nbd_update_server_fd_handler(int fd);
357
358 static void nbd_client_closed(NBDClient *client)
359 {
360 nb_fds--;
361 if (nb_fds == 0 && !persistent && state == RUNNING) {
362 state = TERMINATE;
363 }
364 nbd_update_server_fd_handler(server_fd);
365 qemu_notify_event();
366 nbd_client_put(client);
367 }
368
369 static void nbd_accept(void *opaque)
370 {
371 struct sockaddr_in addr;
372 socklen_t addr_len = sizeof(addr);
373
374 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len);
375 if (fd < 0) {
376 perror("accept");
377 return;
378 }
379
380 if (state >= TERMINATE) {
381 close(fd);
382 return;
383 }
384
385 if (nbd_client_new(exp, fd, nbd_client_closed)) {
386 nb_fds++;
387 nbd_update_server_fd_handler(server_fd);
388 } else {
389 shutdown(fd, 2);
390 close(fd);
391 }
392 }
393
394 static void nbd_update_server_fd_handler(int fd)
395 {
396 if (nbd_can_accept()) {
397 qemu_set_fd_handler(fd, nbd_accept, NULL, (void *)(uintptr_t)fd);
398 } else {
399 qemu_set_fd_handler(fd, NULL, NULL, NULL);
400 }
401 }
402
403 int main(int argc, char **argv)
404 {
405 BlockBackend *blk;
406 BlockDriverState *bs;
407 off_t dev_offset = 0;
408 uint32_t nbdflags = 0;
409 bool disconnect = false;
410 const char *bindto = "0.0.0.0";
411 char *device = NULL;
412 int port = NBD_DEFAULT_PORT;
413 off_t fd_size;
414 QemuOpts *sn_opts = NULL;
415 const char *sn_id_or_name = NULL;
416 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:";
417 struct option lopt[] = {
418 { "help", 0, NULL, 'h' },
419 { "version", 0, NULL, 'V' },
420 { "bind", 1, NULL, 'b' },
421 { "port", 1, NULL, 'p' },
422 { "socket", 1, NULL, 'k' },
423 { "offset", 1, NULL, 'o' },
424 { "read-only", 0, NULL, 'r' },
425 { "partition", 1, NULL, 'P' },
426 { "connect", 1, NULL, 'c' },
427 { "disconnect", 0, NULL, 'd' },
428 { "snapshot", 0, NULL, 's' },
429 { "load-snapshot", 1, NULL, 'l' },
430 { "nocache", 0, NULL, 'n' },
431 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE },
432 #ifdef CONFIG_LINUX_AIO
433 { "aio", 1, NULL, QEMU_NBD_OPT_AIO },
434 #endif
435 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
436 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES },
437 { "shared", 1, NULL, 'e' },
438 { "format", 1, NULL, 'f' },
439 { "persistent", 0, NULL, 't' },
440 { "verbose", 0, NULL, 'v' },
441 { NULL, 0, NULL, 0 }
442 };
443 int ch;
444 int opt_ind = 0;
445 int li;
446 char *end;
447 int flags = BDRV_O_RDWR;
448 int partition = -1;
449 int ret = 0;
450 int fd;
451 bool seen_cache = false;
452 bool seen_discard = false;
453 #ifdef CONFIG_LINUX_AIO
454 bool seen_aio = false;
455 #endif
456 pthread_t client_thread;
457 const char *fmt = NULL;
458 Error *local_err = NULL;
459 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
460 QDict *options = NULL;
461
462 /* The client thread uses SIGTERM to interrupt the server. A signal
463 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
464 */
465 struct sigaction sa_sigterm;
466 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
467 sa_sigterm.sa_handler = termsig_handler;
468 sigaction(SIGTERM, &sa_sigterm, NULL);
469 qemu_init_exec_dir(argv[0]);
470
471 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
472 switch (ch) {
473 case 's':
474 flags |= BDRV_O_SNAPSHOT;
475 break;
476 case 'n':
477 optarg = (char *) "none";
478 /* fallthrough */
479 case QEMU_NBD_OPT_CACHE:
480 if (seen_cache) {
481 errx(EXIT_FAILURE, "-n and --cache can only be specified once");
482 }
483 seen_cache = true;
484 if (bdrv_parse_cache_flags(optarg, &flags) == -1) {
485 errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg);
486 }
487 break;
488 #ifdef CONFIG_LINUX_AIO
489 case QEMU_NBD_OPT_AIO:
490 if (seen_aio) {
491 errx(EXIT_FAILURE, "--aio can only be specified once");
492 }
493 seen_aio = true;
494 if (!strcmp(optarg, "native")) {
495 flags |= BDRV_O_NATIVE_AIO;
496 } else if (!strcmp(optarg, "threads")) {
497 /* this is the default */
498 } else {
499 errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg);
500 }
501 break;
502 #endif
503 case QEMU_NBD_OPT_DISCARD:
504 if (seen_discard) {
505 errx(EXIT_FAILURE, "--discard can only be specified once");
506 }
507 seen_discard = true;
508 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
509 errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg);
510 }
511 break;
512 case QEMU_NBD_OPT_DETECT_ZEROES:
513 detect_zeroes =
514 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
515 optarg,
516 BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX,
517 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
518 &local_err);
519 if (local_err) {
520 errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s",
521 error_get_pretty(local_err));
522 }
523 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
524 !(flags & BDRV_O_UNMAP)) {
525 errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed "
526 "without setting discard operation to unmap");
527 }
528 break;
529 case 'b':
530 bindto = optarg;
531 break;
532 case 'p':
533 li = strtol(optarg, &end, 0);
534 if (*end) {
535 errx(EXIT_FAILURE, "Invalid port `%s'", optarg);
536 }
537 if (li < 1 || li > 65535) {
538 errx(EXIT_FAILURE, "Port out of range `%s'", optarg);
539 }
540 port = (uint16_t)li;
541 break;
542 case 'o':
543 dev_offset = strtoll (optarg, &end, 0);
544 if (*end) {
545 errx(EXIT_FAILURE, "Invalid offset `%s'", optarg);
546 }
547 if (dev_offset < 0) {
548 errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg);
549 }
550 break;
551 case 'l':
552 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
553 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
554 optarg, false);
555 if (!sn_opts) {
556 errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'",
557 optarg);
558 }
559 } else {
560 sn_id_or_name = optarg;
561 }
562 /* fall through */
563 case 'r':
564 nbdflags |= NBD_FLAG_READ_ONLY;
565 flags &= ~BDRV_O_RDWR;
566 break;
567 case 'P':
568 partition = strtol(optarg, &end, 0);
569 if (*end) {
570 errx(EXIT_FAILURE, "Invalid partition `%s'", optarg);
571 }
572 if (partition < 1 || partition > 8) {
573 errx(EXIT_FAILURE, "Invalid partition %d", partition);
574 }
575 break;
576 case 'k':
577 sockpath = optarg;
578 if (sockpath[0] != '/') {
579 errx(EXIT_FAILURE, "socket path must be absolute\n");
580 }
581 break;
582 case 'd':
583 disconnect = true;
584 break;
585 case 'c':
586 device = optarg;
587 break;
588 case 'e':
589 shared = strtol(optarg, &end, 0);
590 if (*end) {
591 errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg);
592 }
593 if (shared < 1) {
594 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
595 }
596 break;
597 case 'f':
598 fmt = optarg;
599 break;
600 case 't':
601 persistent = 1;
602 break;
603 case 'v':
604 verbose = 1;
605 break;
606 case 'V':
607 version(argv[0]);
608 exit(0);
609 break;
610 case 'h':
611 usage(argv[0]);
612 exit(0);
613 break;
614 case '?':
615 errx(EXIT_FAILURE, "Try `%s --help' for more information.",
616 argv[0]);
617 }
618 }
619
620 if ((argc - optind) != 1) {
621 errx(EXIT_FAILURE, "Invalid number of argument.\n"
622 "Try `%s --help' for more information.",
623 argv[0]);
624 }
625
626 if (disconnect) {
627 fd = open(argv[optind], O_RDWR);
628 if (fd < 0) {
629 err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
630 }
631 nbd_disconnect(fd);
632
633 close(fd);
634
635 printf("%s disconnected\n", argv[optind]);
636
637 return 0;
638 }
639
640 if (device && !verbose) {
641 int stderr_fd[2];
642 pid_t pid;
643 int ret;
644
645 if (qemu_pipe(stderr_fd) < 0) {
646 err(EXIT_FAILURE, "Error setting up communication pipe");
647 }
648
649 /* Now daemonize, but keep a communication channel open to
650 * print errors and exit with the proper status code.
651 */
652 pid = fork();
653 if (pid < 0) {
654 err(EXIT_FAILURE, "Failed to fork");
655 } else if (pid == 0) {
656 close(stderr_fd[0]);
657 ret = qemu_daemon(1, 0);
658
659 /* Temporarily redirect stderr to the parent's pipe... */
660 dup2(stderr_fd[1], STDERR_FILENO);
661 if (ret < 0) {
662 err(EXIT_FAILURE, "Failed to daemonize");
663 }
664
665 /* ... close the descriptor we inherited and go on. */
666 close(stderr_fd[1]);
667 } else {
668 bool errors = false;
669 char *buf;
670
671 /* In the parent. Print error messages from the child until
672 * it closes the pipe.
673 */
674 close(stderr_fd[1]);
675 buf = g_malloc(1024);
676 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
677 errors = true;
678 ret = qemu_write_full(STDERR_FILENO, buf, ret);
679 if (ret < 0) {
680 exit(EXIT_FAILURE);
681 }
682 }
683 if (ret < 0) {
684 err(EXIT_FAILURE, "Cannot read from daemon");
685 }
686
687 /* Usually the daemon should not print any message.
688 * Exit with zero status in that case.
689 */
690 exit(errors);
691 }
692 }
693
694 if (device != NULL && sockpath == NULL) {
695 sockpath = g_malloc(128);
696 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
697 }
698
699 if (qemu_init_main_loop(&local_err)) {
700 error_report_err(local_err);
701 exit(EXIT_FAILURE);
702 }
703 bdrv_init();
704 atexit(bdrv_close_all);
705
706 if (fmt) {
707 options = qdict_new();
708 qdict_put(options, "driver", qstring_from_str(fmt));
709 }
710
711 srcpath = argv[optind];
712 blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err);
713 if (!blk) {
714 errx(EXIT_FAILURE, "Failed to blk_new_open '%s': %s", argv[optind],
715 error_get_pretty(local_err));
716 }
717 bs = blk_bs(blk);
718
719 if (sn_opts) {
720 ret = bdrv_snapshot_load_tmp(bs,
721 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
722 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
723 &local_err);
724 } else if (sn_id_or_name) {
725 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
726 &local_err);
727 }
728 if (ret < 0) {
729 errno = -ret;
730 err(EXIT_FAILURE,
731 "Failed to load snapshot: %s",
732 error_get_pretty(local_err));
733 }
734
735 bs->detect_zeroes = detect_zeroes;
736 fd_size = blk_getlength(blk);
737 if (fd_size < 0) {
738 errx(EXIT_FAILURE, "Failed to determine the image length: %s",
739 strerror(-fd_size));
740 }
741
742 if (partition != -1) {
743 ret = find_partition(blk, partition, &dev_offset, &fd_size);
744 if (ret < 0) {
745 errno = -ret;
746 err(EXIT_FAILURE, "Could not find partition %d", partition);
747 }
748 }
749
750 exp = nbd_export_new(blk, dev_offset, fd_size, nbdflags, nbd_export_closed,
751 &local_err);
752 if (!exp) {
753 errx(EXIT_FAILURE, "%s", error_get_pretty(local_err));
754 }
755
756 if (sockpath) {
757 fd = unix_socket_incoming(sockpath);
758 } else {
759 fd = tcp_socket_incoming(bindto, port);
760 }
761
762 if (fd < 0) {
763 return 1;
764 }
765
766 if (device) {
767 int ret;
768
769 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
770 if (ret != 0) {
771 errx(EXIT_FAILURE, "Failed to create client thread: %s",
772 strerror(ret));
773 }
774 } else {
775 /* Shut up GCC warnings. */
776 memset(&client_thread, 0, sizeof(client_thread));
777 }
778
779 server_fd = fd;
780 nbd_update_server_fd_handler(fd);
781
782 /* now when the initialization is (almost) complete, chdir("/")
783 * to free any busy filesystems */
784 if (chdir("/") < 0) {
785 err(EXIT_FAILURE, "Could not chdir to root directory");
786 }
787
788 state = RUNNING;
789 do {
790 main_loop_wait(false);
791 if (state == TERMINATE) {
792 state = TERMINATING;
793 nbd_export_close(exp);
794 nbd_export_put(exp);
795 exp = NULL;
796 }
797 } while (state != TERMINATED);
798
799 blk_unref(blk);
800 if (sockpath) {
801 unlink(sockpath);
802 }
803
804 qemu_opts_del(sn_opts);
805
806 if (device) {
807 void *ret;
808 pthread_join(client_thread, &ret);
809 exit(ret != NULL);
810 } else {
811 exit(EXIT_SUCCESS);
812 }
813 }