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cd831bd7 1/*
7a5ca864
FB
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
8167ee88 16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
7a5ca864
FB
17 */
18
5a61cb60 19#include "qemu-common.h"
26f54e9a 20#include "sysemu/block-backend.h"
b3838a40 21#include "block/block_int.h"
737e150e 22#include "block/nbd.h"
6a1751b7 23#include "qemu/main-loop.h"
537b41f5
PB
24#include "qemu/sockets.h"
25#include "qemu/error-report.h"
8c116b0e 26#include "block/snapshot.h"
b3838a40 27#include "qapi/util.h"
d49b6836 28#include "qapi/qmp/qstring.h"
7a5ca864 29
7a5ca864
FB
30#include <stdarg.h>
31#include <stdio.h>
32#include <getopt.h>
cd831bd7 33#include <sys/types.h>
7a5ca864
FB
34#include <sys/socket.h>
35#include <netinet/in.h>
36#include <netinet/tcp.h>
37#include <arpa/inet.h>
cd831bd7 38#include <signal.h>
2bff4b6f 39#include <libgen.h>
a517e88b 40#include <pthread.h>
cd831bd7 41
713cc671
PL
42#define SOCKET_PATH "/var/lock/qemu-nbd-%s"
43#define QEMU_NBD_OPT_CACHE 1
44#define QEMU_NBD_OPT_AIO 2
45#define QEMU_NBD_OPT_DISCARD 3
b3838a40 46#define QEMU_NBD_OPT_DETECT_ZEROES 4
7a5ca864 47
af49bbbe 48static NBDExport *exp;
b1d8e52e 49static int verbose;
a517e88b 50static char *srcpath;
48bec07e 51static SocketAddress *saddr;
7860a380
PB
52static int persistent = 0;
53static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
a61c6782
PB
54static int shared = 1;
55static int nb_fds;
e4afbf4f 56static int server_fd;
7a5ca864
FB
57
58static void usage(const char *name)
59{
b033cd86 60 (printf) (
7a5ca864
FB
61"Usage: %s [OPTIONS] FILE\n"
62"QEMU Disk Network Block Device Server\n"
63"\n"
713cc671
PL
64" -h, --help display this help and exit\n"
65" -V, --version output version information and exit\n"
b033cd86
PB
66"\n"
67"Connection properties:\n"
713cc671
PL
68" -p, --port=PORT port to listen on (default `%d')\n"
69" -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
70" -k, --socket=PATH path to the unix socket\n"
71" (default '"SOCKET_PATH"')\n"
72" -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
73" -t, --persistent don't exit on the last connection\n"
74" -v, --verbose display extra debugging information\n"
7a5ca864 75"\n"
b033cd86 76"Exposing part of the image:\n"
713cc671
PL
77" -o, --offset=OFFSET offset into the image\n"
78" -P, --partition=NUM only expose partition NUM\n"
b033cd86
PB
79"\n"
80#ifdef __linux__
81"Kernel NBD client support:\n"
713cc671
PL
82" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
83" -d, --disconnect disconnect the specified device\n"
b033cd86
PB
84"\n"
85#endif
86"\n"
87"Block device options:\n"
713cc671
PL
88" -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
89" -r, --read-only export read-only\n"
90" -s, --snapshot use FILE as an external snapshot, create a temporary\n"
91" file with backing_file=FILE, redirect the write to\n"
92" the temporary one\n"
8c116b0e 93" -l, --load-snapshot=SNAPSHOT_PARAM\n"
713cc671
PL
94" load an internal snapshot inside FILE and export it\n"
95" as an read-only device, SNAPSHOT_PARAM format is\n"
96" 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
97" '[ID_OR_NAME]'\n"
98" -n, --nocache disable host cache\n"
99" --cache=MODE set cache mode (none, writeback, ...)\n"
713cc671 100" --aio=MODE set AIO mode (native or threads)\n"
b3838a40 101" --discard=MODE set discard mode (ignore, unmap)\n"
6883de6c 102" --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
b033cd86
PB
103"\n"
104"Report bugs to <qemu-devel@nongnu.org>\n"
c2e2872b 105 , name, NBD_DEFAULT_PORT, "DEVICE");
7a5ca864
FB
106}
107
108static void version(const char *name)
109{
110 printf(
315bc7aa 111"%s version 0.0.1\n"
7a5ca864
FB
112"Written by Anthony Liguori.\n"
113"\n"
114"Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n"
115"This is free software; see the source for copying conditions. There is NO\n"
116"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
315bc7aa 117 , name);
7a5ca864
FB
118}
119
120struct partition_record
121{
122 uint8_t bootable;
123 uint8_t start_head;
124 uint32_t start_cylinder;
125 uint8_t start_sector;
126 uint8_t system;
127 uint8_t end_head;
128 uint8_t end_cylinder;
129 uint8_t end_sector;
130 uint32_t start_sector_abs;
131 uint32_t nb_sectors_abs;
132};
133
134static void read_partition(uint8_t *p, struct partition_record *r)
135{
136 r->bootable = p[0];
137 r->start_head = p[1];
138 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
139 r->start_sector = p[2] & 0x3f;
140 r->system = p[4];
141 r->end_head = p[5];
142 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
143 r->end_sector = p[6] & 0x3f;
ac97393d
HR
144
145 r->start_sector_abs = le32_to_cpup((uint32_t *)(p + 8));
146 r->nb_sectors_abs = le32_to_cpup((uint32_t *)(p + 12));
7a5ca864
FB
147}
148
4c58e80a 149static int find_partition(BlockBackend *blk, int partition,
7a5ca864
FB
150 off_t *offset, off_t *size)
151{
152 struct partition_record mbr[4];
153 uint8_t data[512];
154 int i;
155 int ext_partnum = 4;
cb7cf0e3 156 int ret;
7a5ca864 157
4c58e80a 158 if ((ret = blk_read(blk, 0, data, 1)) < 0) {
cb7cf0e3 159 errno = -ret;
85b01e09
MA
160 error_report("error while reading: %s", strerror(errno));
161 exit(EXIT_FAILURE);
cb7cf0e3 162 }
7a5ca864
FB
163
164 if (data[510] != 0x55 || data[511] != 0xaa) {
185b4338 165 return -EINVAL;
7a5ca864
FB
166 }
167
168 for (i = 0; i < 4; i++) {
169 read_partition(&data[446 + 16 * i], &mbr[i]);
170
453b07b1 171 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
7a5ca864 172 continue;
453b07b1 173 }
7a5ca864
FB
174
175 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
176 struct partition_record ext[4];
177 uint8_t data1[512];
178 int j;
179
4c58e80a 180 if ((ret = blk_read(blk, mbr[i].start_sector_abs, data1, 1)) < 0) {
cb7cf0e3 181 errno = -ret;
85b01e09
MA
182 error_report("error while reading: %s", strerror(errno));
183 exit(EXIT_FAILURE);
cb7cf0e3 184 }
7a5ca864
FB
185
186 for (j = 0; j < 4; j++) {
187 read_partition(&data1[446 + 16 * j], &ext[j]);
453b07b1 188 if (!ext[j].system || !ext[j].nb_sectors_abs) {
7a5ca864 189 continue;
453b07b1 190 }
7a5ca864
FB
191
192 if ((ext_partnum + j + 1) == partition) {
193 *offset = (uint64_t)ext[j].start_sector_abs << 9;
194 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
195 return 0;
196 }
197 }
198 ext_partnum += 4;
199 } else if ((i + 1) == partition) {
200 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
201 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
202 return 0;
203 }
204 }
205
185b4338 206 return -ENOENT;
7a5ca864
FB
207}
208
bb345110
PB
209static void termsig_handler(int signum)
210{
7860a380 211 state = TERMINATE;
a61c6782 212 qemu_notify_event();
bb345110
PB
213}
214
537b41f5 215
a517e88b 216static void *show_parts(void *arg)
cd831bd7 217{
a6ac2313 218 char *device = arg;
a517e88b
PB
219 int nbd;
220
221 /* linux just needs an open() to trigger
222 * the partition table update
223 * but remember to load the module with max_part != 0 :
224 * modprobe nbd max_part=63
225 */
226 nbd = open(device, O_RDWR);
fc19f8a0 227 if (nbd >= 0) {
a517e88b
PB
228 close(nbd);
229 }
230 return NULL;
231}
cd831bd7 232
a517e88b
PB
233static void *nbd_client_thread(void *arg)
234{
a6ac2313 235 char *device = arg;
a517e88b 236 off_t size;
a517e88b 237 uint32_t nbdflags;
a6ac2313 238 int fd, sock;
a517e88b
PB
239 int ret;
240 pthread_t show_parts_thread;
1ce52846 241 Error *local_error = NULL;
a517e88b 242
48bec07e
DB
243
244 sock = socket_connect(saddr, &local_error, NULL, NULL);
fc19f8a0 245 if (sock < 0) {
48bec07e 246 error_report_err(local_error);
dc10e8b3
SH
247 goto out;
248 }
a517e88b
PB
249
250 ret = nbd_receive_negotiate(sock, NULL, &nbdflags,
3f472659 251 &size, &local_error);
fc19f8a0 252 if (ret < 0) {
1ce52846 253 if (local_error) {
78288671 254 error_report_err(local_error);
1ce52846 255 }
0c544d73 256 goto out_socket;
a517e88b
PB
257 }
258
a6ac2313 259 fd = open(device, O_RDWR);
fc19f8a0 260 if (fd < 0) {
a6ac2313 261 /* Linux-only, we can use %m in printf. */
5672ee54 262 fprintf(stderr, "Failed to open %s: %m\n", device);
0c544d73 263 goto out_socket;
a6ac2313
PB
264 }
265
3f472659 266 ret = nbd_init(fd, sock, nbdflags, size);
fc19f8a0 267 if (ret < 0) {
0c544d73 268 goto out_fd;
a517e88b
PB
269 }
270
271 /* update partition table */
a6ac2313 272 pthread_create(&show_parts_thread, NULL, show_parts, device);
a517e88b 273
c1f8fdc3
PB
274 if (verbose) {
275 fprintf(stderr, "NBD device %s is now connected to %s\n",
276 device, srcpath);
277 } else {
278 /* Close stderr so that the qemu-nbd process exits. */
279 dup2(STDOUT_FILENO, STDERR_FILENO);
280 }
a517e88b
PB
281
282 ret = nbd_client(fd);
283 if (ret) {
0c544d73 284 goto out_fd;
cd831bd7 285 }
a517e88b
PB
286 close(fd);
287 kill(getpid(), SIGTERM);
288 return (void *) EXIT_SUCCESS;
289
0c544d73
PB
290out_fd:
291 close(fd);
292out_socket:
293 closesocket(sock);
a517e88b
PB
294out:
295 kill(getpid(), SIGTERM);
296 return (void *) EXIT_FAILURE;
cd831bd7
TS
297}
298
e4afbf4f 299static int nbd_can_accept(void)
a61c6782
PB
300{
301 return nb_fds < shared;
302}
303
7860a380
PB
304static void nbd_export_closed(NBDExport *exp)
305{
306 assert(state == TERMINATING);
307 state = TERMINATED;
308}
309
e4afbf4f
FZ
310static void nbd_update_server_fd_handler(int fd);
311
1743b515 312static void nbd_client_closed(NBDClient *client)
a61c6782 313{
1743b515 314 nb_fds--;
7860a380
PB
315 if (nb_fds == 0 && !persistent && state == RUNNING) {
316 state = TERMINATE;
317 }
e4afbf4f 318 nbd_update_server_fd_handler(server_fd);
7860a380 319 nbd_client_put(client);
a61c6782
PB
320}
321
322static void nbd_accept(void *opaque)
323{
a61c6782
PB
324 struct sockaddr_in addr;
325 socklen_t addr_len = sizeof(addr);
326
327 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len);
0c544d73
PB
328 if (fd < 0) {
329 perror("accept");
330 return;
331 }
332
7860a380
PB
333 if (state >= TERMINATE) {
334 close(fd);
335 return;
336 }
337
36af5994 338 if (nbd_client_new(exp, fd, nbd_client_closed)) {
a61c6782 339 nb_fds++;
e4afbf4f 340 nbd_update_server_fd_handler(server_fd);
36af5994 341 } else {
27e5eae4 342 shutdown(fd, 2);
36af5994 343 close(fd);
a61c6782
PB
344 }
345}
346
e4afbf4f
FZ
347static void nbd_update_server_fd_handler(int fd)
348{
349 if (nbd_can_accept()) {
350 qemu_set_fd_handler(fd, nbd_accept, NULL, (void *)(uintptr_t)fd);
351 } else {
352 qemu_set_fd_handler(fd, NULL, NULL, NULL);
353 }
354}
355
48bec07e
DB
356
357static SocketAddress *nbd_build_socket_address(const char *sockpath,
358 const char *bindto,
359 const char *port)
360{
361 SocketAddress *saddr;
362
363 saddr = g_new0(SocketAddress, 1);
364 if (sockpath) {
2d32adda
EB
365 saddr->type = SOCKET_ADDRESS_KIND_UNIX;
366 saddr->u.q_unix = g_new0(UnixSocketAddress, 1);
367 saddr->u.q_unix->path = g_strdup(sockpath);
48bec07e 368 } else {
2d32adda
EB
369 saddr->type = SOCKET_ADDRESS_KIND_INET;
370 saddr->u.inet = g_new0(InetSocketAddress, 1);
371 saddr->u.inet->host = g_strdup(bindto);
48bec07e 372 if (port) {
2d32adda 373 saddr->u.inet->port = g_strdup(port);
48bec07e 374 } else {
2d32adda 375 saddr->u.inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
48bec07e
DB
376 }
377 }
378
379 return saddr;
380}
381
382
7a5ca864
FB
383int main(int argc, char **argv)
384{
26f54e9a 385 BlockBackend *blk;
7a5ca864
FB
386 BlockDriverState *bs;
387 off_t dev_offset = 0;
b90fb4b8 388 uint32_t nbdflags = 0;
cd831bd7 389 bool disconnect = false;
7a5ca864 390 const char *bindto = "0.0.0.0";
48bec07e
DB
391 const char *port = NULL;
392 char *sockpath = NULL;
a6ac2313 393 char *device = NULL;
7a5ca864 394 off_t fd_size;
8c116b0e
WX
395 QemuOpts *sn_opts = NULL;
396 const char *sn_id_or_name = NULL;
397 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:";
7a5ca864 398 struct option lopt[] = {
660f11be
BS
399 { "help", 0, NULL, 'h' },
400 { "version", 0, NULL, 'V' },
401 { "bind", 1, NULL, 'b' },
402 { "port", 1, NULL, 'p' },
403 { "socket", 1, NULL, 'k' },
404 { "offset", 1, NULL, 'o' },
405 { "read-only", 0, NULL, 'r' },
406 { "partition", 1, NULL, 'P' },
407 { "connect", 1, NULL, 'c' },
408 { "disconnect", 0, NULL, 'd' },
409 { "snapshot", 0, NULL, 's' },
8c116b0e 410 { "load-snapshot", 1, NULL, 'l' },
660f11be 411 { "nocache", 0, NULL, 'n' },
39a5235c 412 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE },
39a5235c 413 { "aio", 1, NULL, QEMU_NBD_OPT_AIO },
ded9d2d5 414 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
b3838a40 415 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES },
660f11be 416 { "shared", 1, NULL, 'e' },
e6b63677 417 { "format", 1, NULL, 'f' },
660f11be
BS
418 { "persistent", 0, NULL, 't' },
419 { "verbose", 0, NULL, 'v' },
420 { NULL, 0, NULL, 0 }
7a5ca864
FB
421 };
422 int ch;
423 int opt_ind = 0;
7a5ca864 424 char *end;
f5edb014 425 int flags = BDRV_O_RDWR;
7a5ca864 426 int partition = -1;
4fbec260 427 int ret = 0;
3b05a8e9 428 int fd;
39a5235c 429 bool seen_cache = false;
ded9d2d5 430 bool seen_discard = false;
39a5235c 431 bool seen_aio = false;
a517e88b 432 pthread_t client_thread;
e6b63677 433 const char *fmt = NULL;
34b5d2c6 434 Error *local_err = NULL;
b3838a40 435 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
4fbec260 436 QDict *options = NULL;
7a5ca864 437
a517e88b
PB
438 /* The client thread uses SIGTERM to interrupt the server. A signal
439 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
440 */
bb345110 441 struct sigaction sa_sigterm;
bb345110
PB
442 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
443 sa_sigterm.sa_handler = termsig_handler;
444 sigaction(SIGTERM, &sa_sigterm, NULL);
10f5bff6 445 qemu_init_exec_dir(argv[0]);
bb345110 446
7a5ca864
FB
447 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
448 switch (ch) {
449 case 's':
2f726488
TS
450 flags |= BDRV_O_SNAPSHOT;
451 break;
452 case 'n':
39a5235c
PB
453 optarg = (char *) "none";
454 /* fallthrough */
455 case QEMU_NBD_OPT_CACHE:
456 if (seen_cache) {
85b01e09
MA
457 error_report("-n and --cache can only be specified once");
458 exit(EXIT_FAILURE);
39a5235c
PB
459 }
460 seen_cache = true;
461 if (bdrv_parse_cache_flags(optarg, &flags) == -1) {
85b01e09
MA
462 error_report("Invalid cache mode `%s'", optarg);
463 exit(EXIT_FAILURE);
39a5235c 464 }
7a5ca864 465 break;
39a5235c
PB
466 case QEMU_NBD_OPT_AIO:
467 if (seen_aio) {
85b01e09
MA
468 error_report("--aio can only be specified once");
469 exit(EXIT_FAILURE);
39a5235c
PB
470 }
471 seen_aio = true;
472 if (!strcmp(optarg, "native")) {
473 flags |= BDRV_O_NATIVE_AIO;
474 } else if (!strcmp(optarg, "threads")) {
475 /* this is the default */
476 } else {
85b01e09
MA
477 error_report("invalid aio mode `%s'", optarg);
478 exit(EXIT_FAILURE);
39a5235c
PB
479 }
480 break;
ded9d2d5
PB
481 case QEMU_NBD_OPT_DISCARD:
482 if (seen_discard) {
85b01e09
MA
483 error_report("--discard can only be specified once");
484 exit(EXIT_FAILURE);
ded9d2d5
PB
485 }
486 seen_discard = true;
487 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
85b01e09
MA
488 error_report("Invalid discard mode `%s'", optarg);
489 exit(EXIT_FAILURE);
ded9d2d5
PB
490 }
491 break;
b3838a40
PL
492 case QEMU_NBD_OPT_DETECT_ZEROES:
493 detect_zeroes =
494 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
495 optarg,
7fb1cf16 496 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX,
b3838a40
PL
497 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
498 &local_err);
499 if (local_err) {
85b01e09
MA
500 error_report("Failed to parse detect_zeroes mode: %s",
501 error_get_pretty(local_err));
502 exit(EXIT_FAILURE);
b3838a40
PL
503 }
504 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
505 !(flags & BDRV_O_UNMAP)) {
85b01e09
MA
506 error_report("setting detect-zeroes to unmap is not allowed "
507 "without setting discard operation to unmap");
508 exit(EXIT_FAILURE);
b3838a40
PL
509 }
510 break;
7a5ca864
FB
511 case 'b':
512 bindto = optarg;
513 break;
514 case 'p':
48bec07e 515 port = optarg;
7a5ca864
FB
516 break;
517 case 'o':
518 dev_offset = strtoll (optarg, &end, 0);
519 if (*end) {
85b01e09
MA
520 error_report("Invalid offset `%s'", optarg);
521 exit(EXIT_FAILURE);
7a5ca864
FB
522 }
523 if (dev_offset < 0) {
85b01e09
MA
524 error_report("Offset must be positive `%s'", optarg);
525 exit(EXIT_FAILURE);
7a5ca864
FB
526 }
527 break;
8c116b0e
WX
528 case 'l':
529 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
70b94331
MA
530 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
531 optarg, false);
8c116b0e 532 if (!sn_opts) {
85b01e09
MA
533 error_report("Failed in parsing snapshot param `%s'",
534 optarg);
535 exit(EXIT_FAILURE);
8c116b0e
WX
536 }
537 } else {
538 sn_id_or_name = optarg;
539 }
540 /* fall through */
7a5ca864 541 case 'r':
b90fb4b8 542 nbdflags |= NBD_FLAG_READ_ONLY;
07108b29 543 flags &= ~BDRV_O_RDWR;
7a5ca864
FB
544 break;
545 case 'P':
546 partition = strtol(optarg, &end, 0);
713cc671 547 if (*end) {
85b01e09
MA
548 error_report("Invalid partition `%s'", optarg);
549 exit(EXIT_FAILURE);
713cc671
PL
550 }
551 if (partition < 1 || partition > 8) {
85b01e09
MA
552 error_report("Invalid partition %d", partition);
553 exit(EXIT_FAILURE);
713cc671 554 }
7a5ca864 555 break;
cd831bd7 556 case 'k':
b32f6c28 557 sockpath = optarg;
713cc671 558 if (sockpath[0] != '/') {
85b01e09
MA
559 error_report("socket path must be absolute\n");
560 exit(EXIT_FAILURE);
713cc671 561 }
cd831bd7
TS
562 break;
563 case 'd':
564 disconnect = true;
565 break;
566 case 'c':
567 device = optarg;
568 break;
3b05a8e9
TS
569 case 'e':
570 shared = strtol(optarg, &end, 0);
571 if (*end) {
85b01e09
MA
572 error_report("Invalid shared device number '%s'", optarg);
573 exit(EXIT_FAILURE);
3b05a8e9
TS
574 }
575 if (shared < 1) {
85b01e09
MA
576 error_report("Shared device number must be greater than 0\n");
577 exit(EXIT_FAILURE);
3b05a8e9
TS
578 }
579 break;
e6b63677
DB
580 case 'f':
581 fmt = optarg;
582 break;
713cc671
PL
583 case 't':
584 persistent = 1;
585 break;
7a5ca864
FB
586 case 'v':
587 verbose = 1;
588 break;
589 case 'V':
590 version(argv[0]);
591 exit(0);
592 break;
593 case 'h':
594 usage(argv[0]);
595 exit(0);
596 break;
597 case '?':
85b01e09
MA
598 error_report("Try `%s --help' for more information.", argv[0]);
599 exit(EXIT_FAILURE);
7a5ca864
FB
600 }
601 }
602
603 if ((argc - optind) != 1) {
85b01e09
MA
604 error_report("Invalid number of argument.\n"
605 "Try `%s --help' for more information.",
606 argv[0]);
607 exit(EXIT_FAILURE);
7a5ca864
FB
608 }
609
cd831bd7
TS
610 if (disconnect) {
611 fd = open(argv[optind], O_RDWR);
fc19f8a0 612 if (fd < 0) {
85b01e09
MA
613 error_report("Cannot open %s: %s", argv[optind],
614 strerror(errno));
615 exit(EXIT_FAILURE);
fc19f8a0 616 }
cd831bd7
TS
617 nbd_disconnect(fd);
618
619 close(fd);
620
621 printf("%s disconnected\n", argv[optind]);
622
713cc671 623 return 0;
cd831bd7
TS
624 }
625
c1f8fdc3
PB
626 if (device && !verbose) {
627 int stderr_fd[2];
628 pid_t pid;
629 int ret;
630
fc19f8a0 631 if (qemu_pipe(stderr_fd) < 0) {
85b01e09
MA
632 error_report("Error setting up communication pipe: %s",
633 strerror(errno));
634 exit(EXIT_FAILURE);
c1f8fdc3
PB
635 }
636
637 /* Now daemonize, but keep a communication channel open to
638 * print errors and exit with the proper status code.
639 */
640 pid = fork();
70d4739e 641 if (pid < 0) {
85b01e09
MA
642 error_report("Failed to fork: %s", strerror(errno));
643 exit(EXIT_FAILURE);
70d4739e 644 } else if (pid == 0) {
c1f8fdc3 645 close(stderr_fd[0]);
9faf31b6 646 ret = qemu_daemon(1, 0);
c1f8fdc3
PB
647
648 /* Temporarily redirect stderr to the parent's pipe... */
649 dup2(stderr_fd[1], STDERR_FILENO);
fc19f8a0 650 if (ret < 0) {
85b01e09
MA
651 error_report("Failed to daemonize: %s", strerror(errno));
652 exit(EXIT_FAILURE);
c1f8fdc3
PB
653 }
654
655 /* ... close the descriptor we inherited and go on. */
656 close(stderr_fd[1]);
657 } else {
658 bool errors = false;
659 char *buf;
660
661 /* In the parent. Print error messages from the child until
662 * it closes the pipe.
663 */
664 close(stderr_fd[1]);
665 buf = g_malloc(1024);
666 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
667 errors = true;
668 ret = qemu_write_full(STDERR_FILENO, buf, ret);
fc19f8a0 669 if (ret < 0) {
c1f8fdc3
PB
670 exit(EXIT_FAILURE);
671 }
672 }
fc19f8a0 673 if (ret < 0) {
85b01e09
MA
674 error_report("Cannot read from daemon: %s",
675 strerror(errno));
676 exit(EXIT_FAILURE);
c1f8fdc3
PB
677 }
678
679 /* Usually the daemon should not print any message.
680 * Exit with zero status in that case.
681 */
682 exit(errors);
683 }
684 }
685
a6ac2313
PB
686 if (device != NULL && sockpath == NULL) {
687 sockpath = g_malloc(128);
688 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
cd831bd7
TS
689 }
690
48bec07e
DB
691 saddr = nbd_build_socket_address(sockpath, bindto, port);
692
2f78e491 693 if (qemu_init_main_loop(&local_err)) {
565f65d2 694 error_report_err(local_err);
2f78e491
CN
695 exit(EXIT_FAILURE);
696 }
802ddc37
PB
697 bdrv_init();
698 atexit(bdrv_close_all);
699
e6b63677 700 if (fmt) {
4fbec260
HR
701 options = qdict_new();
702 qdict_put(options, "driver", qstring_from_str(fmt));
e6b63677
DB
703 }
704
802ddc37 705 srcpath = argv[optind];
4fbec260
HR
706 blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err);
707 if (!blk) {
85b01e09
MA
708 error_report("Failed to blk_new_open '%s': %s", argv[optind],
709 error_get_pretty(local_err));
710 exit(EXIT_FAILURE);
802ddc37 711 }
4fbec260 712 bs = blk_bs(blk);
802ddc37 713
8c116b0e
WX
714 if (sn_opts) {
715 ret = bdrv_snapshot_load_tmp(bs,
716 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
717 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
718 &local_err);
719 } else if (sn_id_or_name) {
720 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
721 &local_err);
722 }
723 if (ret < 0) {
724 errno = -ret;
85b01e09
MA
725 error_report("Failed to load snapshot: %s: %s",
726 error_get_pretty(local_err), strerror(errno));
727 exit(EXIT_FAILURE);
8c116b0e
WX
728 }
729
b3838a40 730 bs->detect_zeroes = detect_zeroes;
4c58e80a 731 fd_size = blk_getlength(blk);
98f44bbe 732 if (fd_size < 0) {
85b01e09
MA
733 error_report("Failed to determine the image length: %s",
734 strerror(-fd_size));
735 exit(EXIT_FAILURE);
98f44bbe 736 }
802ddc37 737
185b4338 738 if (partition != -1) {
4c58e80a 739 ret = find_partition(blk, partition, &dev_offset, &fd_size);
185b4338
PB
740 if (ret < 0) {
741 errno = -ret;
85b01e09
MA
742 error_report("Could not find partition %d: %s", partition,
743 strerror(errno));
744 exit(EXIT_FAILURE);
185b4338 745 }
802ddc37
PB
746 }
747
98f44bbe
HR
748 exp = nbd_export_new(blk, dev_offset, fd_size, nbdflags, nbd_export_closed,
749 &local_err);
750 if (!exp) {
4fffeb5e 751 error_report_err(local_err);
85b01e09 752 exit(EXIT_FAILURE);
98f44bbe 753 }
3b05a8e9 754
48bec07e 755 fd = socket_listen(saddr, &local_err);
fc19f8a0 756 if (fd < 0) {
48bec07e 757 error_report_err(local_err);
7a5ca864 758 return 1;
a61c6782 759 }
f1ef5555
PB
760
761 if (device) {
762 int ret;
763
a6ac2313 764 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
f1ef5555 765 if (ret != 0) {
85b01e09
MA
766 error_report("Failed to create client thread: %s", strerror(ret));
767 exit(EXIT_FAILURE);
f1ef5555
PB
768 }
769 } else {
770 /* Shut up GCC warnings. */
771 memset(&client_thread, 0, sizeof(client_thread));
772 }
773
e4afbf4f
FZ
774 server_fd = fd;
775 nbd_update_server_fd_handler(fd);
7a5ca864 776
9faf31b6
MT
777 /* now when the initialization is (almost) complete, chdir("/")
778 * to free any busy filesystems */
779 if (chdir("/") < 0) {
85b01e09
MA
780 error_report("Could not chdir to root directory: %s",
781 strerror(errno));
782 exit(EXIT_FAILURE);
9faf31b6
MT
783 }
784
7860a380 785 state = RUNNING;
3b05a8e9 786 do {
a61c6782 787 main_loop_wait(false);
7860a380
PB
788 if (state == TERMINATE) {
789 state = TERMINATING;
790 nbd_export_close(exp);
791 nbd_export_put(exp);
792 exp = NULL;
793 }
794 } while (state != TERMINATED);
7a5ca864 795
26f54e9a 796 blk_unref(blk);
b32f6c28
PB
797 if (sockpath) {
798 unlink(sockpath);
799 }
7a5ca864 800
fbf28a43 801 qemu_opts_del(sn_opts);
8c116b0e 802
a517e88b
PB
803 if (device) {
804 void *ret;
805 pthread_join(client_thread, &ret);
806 exit(ret != NULL);
807 } else {
808 exit(EXIT_SUCCESS);
809 }
7a5ca864 810}