xref: /openbmc/qemu/qemu-nbd.c (revision 0399a381)
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 "block/block.h"
21 #include "block/nbd.h"
22 #include "qemu/main-loop.h"
23 #include "qemu/sockets.h"
24 #include "qemu/error-report.h"
25 #include "block/snapshot.h"
26 
27 #include <stdarg.h>
28 #include <stdio.h>
29 #include <getopt.h>
30 #include <err.h>
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <netinet/in.h>
34 #include <netinet/tcp.h>
35 #include <arpa/inet.h>
36 #include <signal.h>
37 #include <libgen.h>
38 #include <pthread.h>
39 
40 #define SOCKET_PATH          "/var/lock/qemu-nbd-%s"
41 #define QEMU_NBD_OPT_CACHE   1
42 #define QEMU_NBD_OPT_AIO     2
43 #define QEMU_NBD_OPT_DISCARD 3
44 
45 static NBDExport *exp;
46 static int verbose;
47 static char *srcpath;
48 static char *sockpath;
49 static int persistent = 0;
50 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
51 static int shared = 1;
52 static int nb_fds;
53 
54 static void usage(const char *name)
55 {
56     (printf) (
57 "Usage: %s [OPTIONS] FILE\n"
58 "QEMU Disk Network Block Device Server\n"
59 "\n"
60 "  -h, --help           display this help and exit\n"
61 "  -V, --version        output version information and exit\n"
62 "\n"
63 "Connection properties:\n"
64 "  -p, --port=PORT      port to listen on (default `%d')\n"
65 "  -b, --bind=IFACE     interface to bind to (default `0.0.0.0')\n"
66 "  -k, --socket=PATH    path to the unix socket\n"
67 "                       (default '"SOCKET_PATH"')\n"
68 "  -e, --shared=NUM     device can be shared by NUM clients (default '1')\n"
69 "  -t, --persistent     don't exit on the last connection\n"
70 "  -v, --verbose        display extra debugging information\n"
71 "\n"
72 "Exposing part of the image:\n"
73 "  -o, --offset=OFFSET  offset into the image\n"
74 "  -P, --partition=NUM  only expose partition NUM\n"
75 "\n"
76 #ifdef __linux__
77 "Kernel NBD client support:\n"
78 "  -c, --connect=DEV    connect FILE to the local NBD device DEV\n"
79 "  -d, --disconnect     disconnect the specified device\n"
80 "\n"
81 #endif
82 "\n"
83 "Block device options:\n"
84 "  -f, --format=FORMAT  set image format (raw, qcow2, ...)\n"
85 "  -r, --read-only      export read-only\n"
86 "  -s, --snapshot       use FILE as an external snapshot, create a temporary\n"
87 "                       file with backing_file=FILE, redirect the write to\n"
88 "                       the temporary one\n"
89 "  -l, --load-snapshot=SNAPSHOT_PARAM\n"
90 "                       load an internal snapshot inside FILE and export it\n"
91 "                       as an read-only device, SNAPSHOT_PARAM format is\n"
92 "                       'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
93 "                       '[ID_OR_NAME]'\n"
94 "  -n, --nocache        disable host cache\n"
95 "      --cache=MODE     set cache mode (none, writeback, ...)\n"
96 #ifdef CONFIG_LINUX_AIO
97 "      --aio=MODE       set AIO mode (native or threads)\n"
98 #endif
99 "\n"
100 "Report bugs to <qemu-devel@nongnu.org>\n"
101     , name, NBD_DEFAULT_PORT, "DEVICE");
102 }
103 
104 static void version(const char *name)
105 {
106     printf(
107 "%s version 0.0.1\n"
108 "Written by Anthony Liguori.\n"
109 "\n"
110 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n"
111 "This is free software; see the source for copying conditions.  There is NO\n"
112 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
113     , name);
114 }
115 
116 struct partition_record
117 {
118     uint8_t bootable;
119     uint8_t start_head;
120     uint32_t start_cylinder;
121     uint8_t start_sector;
122     uint8_t system;
123     uint8_t end_head;
124     uint8_t end_cylinder;
125     uint8_t end_sector;
126     uint32_t start_sector_abs;
127     uint32_t nb_sectors_abs;
128 };
129 
130 static void read_partition(uint8_t *p, struct partition_record *r)
131 {
132     r->bootable = p[0];
133     r->start_head = p[1];
134     r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
135     r->start_sector = p[2] & 0x3f;
136     r->system = p[4];
137     r->end_head = p[5];
138     r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
139     r->end_sector = p[6] & 0x3f;
140     r->start_sector_abs = p[8] | p[9] << 8 | p[10] << 16 | p[11] << 24;
141     r->nb_sectors_abs = p[12] | p[13] << 8 | p[14] << 16 | p[15] << 24;
142 }
143 
144 static int find_partition(BlockDriverState *bs, int partition,
145                           off_t *offset, off_t *size)
146 {
147     struct partition_record mbr[4];
148     uint8_t data[512];
149     int i;
150     int ext_partnum = 4;
151     int ret;
152 
153     if ((ret = bdrv_read(bs, 0, data, 1)) < 0) {
154         errno = -ret;
155         err(EXIT_FAILURE, "error while reading");
156     }
157 
158     if (data[510] != 0x55 || data[511] != 0xaa) {
159         return -EINVAL;
160     }
161 
162     for (i = 0; i < 4; i++) {
163         read_partition(&data[446 + 16 * i], &mbr[i]);
164 
165         if (!mbr[i].nb_sectors_abs)
166             continue;
167 
168         if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
169             struct partition_record ext[4];
170             uint8_t data1[512];
171             int j;
172 
173             if ((ret = bdrv_read(bs, mbr[i].start_sector_abs, data1, 1)) < 0) {
174                 errno = -ret;
175                 err(EXIT_FAILURE, "error while reading");
176             }
177 
178             for (j = 0; j < 4; j++) {
179                 read_partition(&data1[446 + 16 * j], &ext[j]);
180                 if (!ext[j].nb_sectors_abs)
181                     continue;
182 
183                 if ((ext_partnum + j + 1) == partition) {
184                     *offset = (uint64_t)ext[j].start_sector_abs << 9;
185                     *size = (uint64_t)ext[j].nb_sectors_abs << 9;
186                     return 0;
187                 }
188             }
189             ext_partnum += 4;
190         } else if ((i + 1) == partition) {
191             *offset = (uint64_t)mbr[i].start_sector_abs << 9;
192             *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
193             return 0;
194         }
195     }
196 
197     return -ENOENT;
198 }
199 
200 static void termsig_handler(int signum)
201 {
202     state = TERMINATE;
203     qemu_notify_event();
204 }
205 
206 static void combine_addr(char *buf, size_t len, const char* address,
207                          uint16_t port)
208 {
209     /* If the address-part contains a colon, it's an IPv6 IP so needs [] */
210     if (strstr(address, ":")) {
211         snprintf(buf, len, "[%s]:%u", address, port);
212     } else {
213         snprintf(buf, len, "%s:%u", address, port);
214     }
215 }
216 
217 static int tcp_socket_incoming(const char *address, uint16_t port)
218 {
219     char address_and_port[128];
220     Error *local_err = NULL;
221 
222     combine_addr(address_and_port, 128, address, port);
223     int fd = inet_listen(address_and_port, NULL, 0, SOCK_STREAM, 0, &local_err);
224 
225     if (local_err != NULL) {
226         qerror_report_err(local_err);
227         error_free(local_err);
228     }
229     return fd;
230 }
231 
232 static int unix_socket_incoming(const char *path)
233 {
234     Error *local_err = NULL;
235     int fd = unix_listen(path, NULL, 0, &local_err);
236 
237     if (local_err != NULL) {
238         qerror_report_err(local_err);
239         error_free(local_err);
240     }
241     return fd;
242 }
243 
244 static int unix_socket_outgoing(const char *path)
245 {
246     Error *local_err = NULL;
247     int fd = unix_connect(path, &local_err);
248 
249     if (local_err != NULL) {
250         qerror_report_err(local_err);
251         error_free(local_err);
252     }
253     return fd;
254 }
255 
256 static void *show_parts(void *arg)
257 {
258     char *device = arg;
259     int nbd;
260 
261     /* linux just needs an open() to trigger
262      * the partition table update
263      * but remember to load the module with max_part != 0 :
264      *     modprobe nbd max_part=63
265      */
266     nbd = open(device, O_RDWR);
267     if (nbd >= 0) {
268         close(nbd);
269     }
270     return NULL;
271 }
272 
273 static void *nbd_client_thread(void *arg)
274 {
275     char *device = arg;
276     off_t size;
277     size_t blocksize;
278     uint32_t nbdflags;
279     int fd, sock;
280     int ret;
281     pthread_t show_parts_thread;
282 
283     sock = unix_socket_outgoing(sockpath);
284     if (sock < 0) {
285         goto out;
286     }
287 
288     ret = nbd_receive_negotiate(sock, NULL, &nbdflags,
289                                 &size, &blocksize);
290     if (ret < 0) {
291         goto out;
292     }
293 
294     fd = open(device, O_RDWR);
295     if (fd < 0) {
296         /* Linux-only, we can use %m in printf.  */
297         fprintf(stderr, "Failed to open %s: %m", device);
298         goto out;
299     }
300 
301     ret = nbd_init(fd, sock, nbdflags, size, blocksize);
302     if (ret < 0) {
303         goto out;
304     }
305 
306     /* update partition table */
307     pthread_create(&show_parts_thread, NULL, show_parts, device);
308 
309     if (verbose) {
310         fprintf(stderr, "NBD device %s is now connected to %s\n",
311                 device, srcpath);
312     } else {
313         /* Close stderr so that the qemu-nbd process exits.  */
314         dup2(STDOUT_FILENO, STDERR_FILENO);
315     }
316 
317     ret = nbd_client(fd);
318     if (ret) {
319         goto out;
320     }
321     close(fd);
322     kill(getpid(), SIGTERM);
323     return (void *) EXIT_SUCCESS;
324 
325 out:
326     kill(getpid(), SIGTERM);
327     return (void *) EXIT_FAILURE;
328 }
329 
330 static int nbd_can_accept(void *opaque)
331 {
332     return nb_fds < shared;
333 }
334 
335 static void nbd_export_closed(NBDExport *exp)
336 {
337     assert(state == TERMINATING);
338     state = TERMINATED;
339 }
340 
341 static void nbd_client_closed(NBDClient *client)
342 {
343     nb_fds--;
344     if (nb_fds == 0 && !persistent && state == RUNNING) {
345         state = TERMINATE;
346     }
347     qemu_notify_event();
348     nbd_client_put(client);
349 }
350 
351 static void nbd_accept(void *opaque)
352 {
353     int server_fd = (uintptr_t) opaque;
354     struct sockaddr_in addr;
355     socklen_t addr_len = sizeof(addr);
356 
357     int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len);
358     if (state >= TERMINATE) {
359         close(fd);
360         return;
361     }
362 
363     if (fd >= 0 && nbd_client_new(exp, fd, nbd_client_closed)) {
364         nb_fds++;
365     }
366 }
367 
368 int main(int argc, char **argv)
369 {
370     BlockDriverState *bs;
371     BlockDriver *drv;
372     off_t dev_offset = 0;
373     uint32_t nbdflags = 0;
374     bool disconnect = false;
375     const char *bindto = "0.0.0.0";
376     char *device = NULL;
377     int port = NBD_DEFAULT_PORT;
378     off_t fd_size;
379     QemuOpts *sn_opts = NULL;
380     const char *sn_id_or_name = NULL;
381     const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:";
382     struct option lopt[] = {
383         { "help", 0, NULL, 'h' },
384         { "version", 0, NULL, 'V' },
385         { "bind", 1, NULL, 'b' },
386         { "port", 1, NULL, 'p' },
387         { "socket", 1, NULL, 'k' },
388         { "offset", 1, NULL, 'o' },
389         { "read-only", 0, NULL, 'r' },
390         { "partition", 1, NULL, 'P' },
391         { "connect", 1, NULL, 'c' },
392         { "disconnect", 0, NULL, 'd' },
393         { "snapshot", 0, NULL, 's' },
394         { "load-snapshot", 1, NULL, 'l' },
395         { "nocache", 0, NULL, 'n' },
396         { "cache", 1, NULL, QEMU_NBD_OPT_CACHE },
397 #ifdef CONFIG_LINUX_AIO
398         { "aio", 1, NULL, QEMU_NBD_OPT_AIO },
399 #endif
400         { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
401         { "shared", 1, NULL, 'e' },
402         { "format", 1, NULL, 'f' },
403         { "persistent", 0, NULL, 't' },
404         { "verbose", 0, NULL, 'v' },
405         { NULL, 0, NULL, 0 }
406     };
407     int ch;
408     int opt_ind = 0;
409     int li;
410     char *end;
411     int flags = BDRV_O_RDWR;
412     int partition = -1;
413     int ret;
414     int fd;
415     bool seen_cache = false;
416     bool seen_discard = false;
417 #ifdef CONFIG_LINUX_AIO
418     bool seen_aio = false;
419 #endif
420     pthread_t client_thread;
421     const char *fmt = NULL;
422     Error *local_err = NULL;
423 
424     /* The client thread uses SIGTERM to interrupt the server.  A signal
425      * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
426      */
427     struct sigaction sa_sigterm;
428     memset(&sa_sigterm, 0, sizeof(sa_sigterm));
429     sa_sigterm.sa_handler = termsig_handler;
430     sigaction(SIGTERM, &sa_sigterm, NULL);
431     qemu_init_exec_dir(argv[0]);
432 
433     while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
434         switch (ch) {
435         case 's':
436             flags |= BDRV_O_SNAPSHOT;
437             break;
438         case 'n':
439             optarg = (char *) "none";
440             /* fallthrough */
441         case QEMU_NBD_OPT_CACHE:
442             if (seen_cache) {
443                 errx(EXIT_FAILURE, "-n and --cache can only be specified once");
444             }
445             seen_cache = true;
446             if (bdrv_parse_cache_flags(optarg, &flags) == -1) {
447                 errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg);
448             }
449             break;
450 #ifdef CONFIG_LINUX_AIO
451         case QEMU_NBD_OPT_AIO:
452             if (seen_aio) {
453                 errx(EXIT_FAILURE, "--aio can only be specified once");
454             }
455             seen_aio = true;
456             if (!strcmp(optarg, "native")) {
457                 flags |= BDRV_O_NATIVE_AIO;
458             } else if (!strcmp(optarg, "threads")) {
459                 /* this is the default */
460             } else {
461                errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg);
462             }
463             break;
464 #endif
465         case QEMU_NBD_OPT_DISCARD:
466             if (seen_discard) {
467                 errx(EXIT_FAILURE, "--discard can only be specified once");
468             }
469             seen_discard = true;
470             if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
471                 errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg);
472             }
473             break;
474         case 'b':
475             bindto = optarg;
476             break;
477         case 'p':
478             li = strtol(optarg, &end, 0);
479             if (*end) {
480                 errx(EXIT_FAILURE, "Invalid port `%s'", optarg);
481             }
482             if (li < 1 || li > 65535) {
483                 errx(EXIT_FAILURE, "Port out of range `%s'", optarg);
484             }
485             port = (uint16_t)li;
486             break;
487         case 'o':
488                 dev_offset = strtoll (optarg, &end, 0);
489             if (*end) {
490                 errx(EXIT_FAILURE, "Invalid offset `%s'", optarg);
491             }
492             if (dev_offset < 0) {
493                 errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg);
494             }
495             break;
496         case 'l':
497             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
498                 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0);
499                 if (!sn_opts) {
500                     errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'",
501                          optarg);
502                 }
503             } else {
504                 sn_id_or_name = optarg;
505             }
506             /* fall through */
507         case 'r':
508             nbdflags |= NBD_FLAG_READ_ONLY;
509             flags &= ~BDRV_O_RDWR;
510             break;
511         case 'P':
512             partition = strtol(optarg, &end, 0);
513             if (*end)
514                 errx(EXIT_FAILURE, "Invalid partition `%s'", optarg);
515             if (partition < 1 || partition > 8)
516                 errx(EXIT_FAILURE, "Invalid partition %d", partition);
517             break;
518         case 'k':
519             sockpath = optarg;
520             if (sockpath[0] != '/')
521                 errx(EXIT_FAILURE, "socket path must be absolute\n");
522             break;
523         case 'd':
524             disconnect = true;
525             break;
526         case 'c':
527             device = optarg;
528             break;
529         case 'e':
530             shared = strtol(optarg, &end, 0);
531             if (*end) {
532                 errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg);
533             }
534             if (shared < 1) {
535                 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
536             }
537             break;
538         case 'f':
539             fmt = optarg;
540             break;
541 	case 't':
542 	    persistent = 1;
543 	    break;
544         case 'v':
545             verbose = 1;
546             break;
547         case 'V':
548             version(argv[0]);
549             exit(0);
550             break;
551         case 'h':
552             usage(argv[0]);
553             exit(0);
554             break;
555         case '?':
556             errx(EXIT_FAILURE, "Try `%s --help' for more information.",
557                  argv[0]);
558         }
559     }
560 
561     if ((argc - optind) != 1) {
562         errx(EXIT_FAILURE, "Invalid number of argument.\n"
563              "Try `%s --help' for more information.",
564              argv[0]);
565     }
566 
567     if (disconnect) {
568         fd = open(argv[optind], O_RDWR);
569         if (fd < 0) {
570             err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
571         }
572         nbd_disconnect(fd);
573 
574         close(fd);
575 
576         printf("%s disconnected\n", argv[optind]);
577 
578 	return 0;
579     }
580 
581     if (device && !verbose) {
582         int stderr_fd[2];
583         pid_t pid;
584         int ret;
585 
586         if (qemu_pipe(stderr_fd) < 0) {
587             err(EXIT_FAILURE, "Error setting up communication pipe");
588         }
589 
590         /* Now daemonize, but keep a communication channel open to
591          * print errors and exit with the proper status code.
592          */
593         pid = fork();
594         if (pid == 0) {
595             close(stderr_fd[0]);
596             ret = qemu_daemon(1, 0);
597 
598             /* Temporarily redirect stderr to the parent's pipe...  */
599             dup2(stderr_fd[1], STDERR_FILENO);
600             if (ret < 0) {
601                 err(EXIT_FAILURE, "Failed to daemonize");
602             }
603 
604             /* ... close the descriptor we inherited and go on.  */
605             close(stderr_fd[1]);
606         } else {
607             bool errors = false;
608             char *buf;
609 
610             /* In the parent.  Print error messages from the child until
611              * it closes the pipe.
612              */
613             close(stderr_fd[1]);
614             buf = g_malloc(1024);
615             while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
616                 errors = true;
617                 ret = qemu_write_full(STDERR_FILENO, buf, ret);
618                 if (ret < 0) {
619                     exit(EXIT_FAILURE);
620                 }
621             }
622             if (ret < 0) {
623                 err(EXIT_FAILURE, "Cannot read from daemon");
624             }
625 
626             /* Usually the daemon should not print any message.
627              * Exit with zero status in that case.
628              */
629             exit(errors);
630         }
631     }
632 
633     if (device != NULL && sockpath == NULL) {
634         sockpath = g_malloc(128);
635         snprintf(sockpath, 128, SOCKET_PATH, basename(device));
636     }
637 
638     qemu_init_main_loop();
639     bdrv_init();
640     atexit(bdrv_close_all);
641 
642     if (fmt) {
643         drv = bdrv_find_format(fmt);
644         if (!drv) {
645             errx(EXIT_FAILURE, "Unknown file format '%s'", fmt);
646         }
647     } else {
648         drv = NULL;
649     }
650 
651     bs = bdrv_new("hda");
652     srcpath = argv[optind];
653     ret = bdrv_open(&bs, srcpath, NULL, NULL, flags, drv, &local_err);
654     if (ret < 0) {
655         errno = -ret;
656         err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind],
657             error_get_pretty(local_err));
658     }
659 
660     if (sn_opts) {
661         ret = bdrv_snapshot_load_tmp(bs,
662                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
663                                      qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
664                                      &local_err);
665     } else if (sn_id_or_name) {
666         ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
667                                                    &local_err);
668     }
669     if (ret < 0) {
670         errno = -ret;
671         err(EXIT_FAILURE,
672             "Failed to load snapshot: %s",
673             error_get_pretty(local_err));
674     }
675 
676     fd_size = bdrv_getlength(bs);
677 
678     if (partition != -1) {
679         ret = find_partition(bs, partition, &dev_offset, &fd_size);
680         if (ret < 0) {
681             errno = -ret;
682             err(EXIT_FAILURE, "Could not find partition %d", partition);
683         }
684     }
685 
686     exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed);
687 
688     if (sockpath) {
689         fd = unix_socket_incoming(sockpath);
690     } else {
691         fd = tcp_socket_incoming(bindto, port);
692     }
693 
694     if (fd < 0) {
695         return 1;
696     }
697 
698     if (device) {
699         int ret;
700 
701         ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
702         if (ret != 0) {
703             errx(EXIT_FAILURE, "Failed to create client thread: %s",
704                  strerror(ret));
705         }
706     } else {
707         /* Shut up GCC warnings.  */
708         memset(&client_thread, 0, sizeof(client_thread));
709     }
710 
711     qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL,
712                          (void *)(uintptr_t)fd);
713 
714     /* now when the initialization is (almost) complete, chdir("/")
715      * to free any busy filesystems */
716     if (chdir("/") < 0) {
717         err(EXIT_FAILURE, "Could not chdir to root directory");
718     }
719 
720     state = RUNNING;
721     do {
722         main_loop_wait(false);
723         if (state == TERMINATE) {
724             state = TERMINATING;
725             nbd_export_close(exp);
726             nbd_export_put(exp);
727             exp = NULL;
728         }
729     } while (state != TERMINATED);
730 
731     bdrv_close(bs);
732     if (sockpath) {
733         unlink(sockpath);
734     }
735 
736     if (sn_opts) {
737         qemu_opts_del(sn_opts);
738     }
739 
740     if (device) {
741         void *ret;
742         pthread_join(client_thread, &ret);
743         exit(ret != NULL);
744     } else {
745         exit(EXIT_SUCCESS);
746     }
747 }
748