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migration: API to clear bits of guest free pages from the dirty bitmap
[qemu/armbru.git] / qemu-nbd.c
blob00c07fd27ea5a9f9f84fed29e988e839d58c0d76
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/osdep.h"
20 #include <getopt.h>
21 #include <libgen.h>
22 #include <pthread.h>
23
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"
45
46 #ifdef __linux__
47 #define HAVE_NBD_DEVICE 1
48 #else
49 #define HAVE_NBD_DEVICE 0
50 #endif
51
52 #define SOCKET_PATH "/var/lock/qemu-nbd-%s"
53 #define QEMU_NBD_OPT_CACHE 256
54 #define QEMU_NBD_OPT_AIO 257
55 #define QEMU_NBD_OPT_DISCARD 258
56 #define QEMU_NBD_OPT_DETECT_ZEROES 259
57 #define QEMU_NBD_OPT_OBJECT 260
58 #define QEMU_NBD_OPT_TLSCREDS 261
59 #define QEMU_NBD_OPT_IMAGE_OPTS 262
60 #define QEMU_NBD_OPT_FORK 263
61
62 #define MBR_SIZE 512
63
64 static NBDExport *export;
65 static int verbose;
66 static char *srcpath;
67 static SocketAddress *saddr;
68 static int persistent = 0;
69 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
70 static int shared = 1;
71 static int nb_fds;
72 static QIONetListener *server;
73 static QCryptoTLSCreds *tlscreds;
74
75 static void usage(const char *name)
76 {
77 (printf) (
78 "Usage: %s [OPTIONS] FILE\n"
79 " or: %s -L [OPTIONS]\n"
80 "QEMU Disk Network Block Device Utility\n"
81 "\n"
82 " -h, --help display this help and exit\n"
83 " -V, --version output version information and exit\n"
84 "\n"
85 "Connection properties:\n"
86 " -p, --port=PORT port to listen on (default `%d')\n"
87 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
88 " -k, --socket=PATH path to the unix socket\n"
89 " (default '"SOCKET_PATH"')\n"
90 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
91 " -t, --persistent don't exit on the last connection\n"
92 " -v, --verbose display extra debugging information\n"
93 " -x, --export-name=NAME expose export by name (default is empty string)\n"
94 " -D, --description=TEXT export a human-readable description\n"
95 "\n"
96 "Exposing part of the image:\n"
97 " -o, --offset=OFFSET offset into the image\n"
98 " -P, --partition=NUM only expose partition NUM\n"
99 " -B, --bitmap=NAME expose a persistent dirty bitmap\n"
100 "\n"
101 "General purpose options:\n"
102 " -L, --list list exports available from another NBD server\n"
103 " --object type,id=ID,... define an object such as 'secret' for providing\n"
104 " passwords and/or encryption keys\n"
105 " --tls-creds=ID use id of an earlier --object to provide TLS\n"
106 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
107 " specify tracing options\n"
108 " --fork fork off the server process and exit the parent\n"
109 " once the server is running\n"
110 #if HAVE_NBD_DEVICE
111 "\n"
112 "Kernel NBD client support:\n"
113 " -c, --connect=DEV connect FILE to the local NBD device DEV\n"
114 " -d, --disconnect disconnect the specified device\n"
115 #endif
116 "\n"
117 "Block device options:\n"
118 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
119 " -r, --read-only export read-only\n"
120 " -s, --snapshot use FILE as an external snapshot, create a temporary\n"
121 " file with backing_file=FILE, redirect the write to\n"
122 " the temporary one\n"
123 " -l, --load-snapshot=SNAPSHOT_PARAM\n"
124 " load an internal snapshot inside FILE and export it\n"
125 " as an read-only device, SNAPSHOT_PARAM format is\n"
126 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
127 " '[ID_OR_NAME]'\n"
128 " -n, --nocache disable host cache\n"
129 " --cache=MODE set cache mode (none, writeback, ...)\n"
130 " --aio=MODE set AIO mode (native or threads)\n"
131 " --discard=MODE set discard mode (ignore, unmap)\n"
132 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n"
133 " --image-opts treat FILE as a full set of image options\n"
134 "\n"
135 QEMU_HELP_BOTTOM "\n"
136 , name, name, NBD_DEFAULT_PORT, "DEVICE");
137 }
138
139 static void version(const char *name)
140 {
141 printf(
142 "%s " QEMU_FULL_VERSION "\n"
143 "Written by Anthony Liguori.\n"
144 "\n"
145 QEMU_COPYRIGHT "\n"
146 "This is free software; see the source for copying conditions. There is NO\n"
147 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
148 , name);
149 }
150
151 struct partition_record
152 {
153 uint8_t bootable;
154 uint8_t start_head;
155 uint32_t start_cylinder;
156 uint8_t start_sector;
157 uint8_t system;
158 uint8_t end_head;
159 uint8_t end_cylinder;
160 uint8_t end_sector;
161 uint32_t start_sector_abs;
162 uint32_t nb_sectors_abs;
163 };
164
165 static void read_partition(uint8_t *p, struct partition_record *r)
166 {
167 r->bootable = p[0];
168 r->start_head = p[1];
169 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
170 r->start_sector = p[2] & 0x3f;
171 r->system = p[4];
172 r->end_head = p[5];
173 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
174 r->end_sector = p[6] & 0x3f;
175
176 r->start_sector_abs = ldl_le_p(p + 8);
177 r->nb_sectors_abs = ldl_le_p(p + 12);
178 }
179
180 static int find_partition(BlockBackend *blk, int partition,
181 uint64_t *offset, uint64_t *size)
182 {
183 struct partition_record mbr[4];
184 uint8_t data[MBR_SIZE];
185 int i;
186 int ext_partnum = 4;
187 int ret;
188
189 ret = blk_pread(blk, 0, data, sizeof(data));
190 if (ret < 0) {
191 error_report("error while reading: %s", strerror(-ret));
192 exit(EXIT_FAILURE);
193 }
194
195 if (data[510] != 0x55 || data[511] != 0xaa) {
196 return -EINVAL;
197 }
198
199 for (i = 0; i < 4; i++) {
200 read_partition(&data[446 + 16 * i], &mbr[i]);
201
202 if (!mbr[i].system || !mbr[i].nb_sectors_abs) {
203 continue;
204 }
205
206 if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
207 struct partition_record ext[4];
208 uint8_t data1[MBR_SIZE];
209 int j;
210
211 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE,
212 data1, sizeof(data1));
213 if (ret < 0) {
214 error_report("error while reading: %s", strerror(-ret));
215 exit(EXIT_FAILURE);
216 }
217
218 for (j = 0; j < 4; j++) {
219 read_partition(&data1[446 + 16 * j], &ext[j]);
220 if (!ext[j].system || !ext[j].nb_sectors_abs) {
221 continue;
222 }
223
224 if ((ext_partnum + j + 1) == partition) {
225 *offset = (uint64_t)ext[j].start_sector_abs << 9;
226 *size = (uint64_t)ext[j].nb_sectors_abs << 9;
227 return 0;
228 }
229 }
230 ext_partnum += 4;
231 } else if ((i + 1) == partition) {
232 *offset = (uint64_t)mbr[i].start_sector_abs << 9;
233 *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
234 return 0;
235 }
236 }
237
238 return -ENOENT;
239 }
240
241 static void termsig_handler(int signum)
242 {
243 atomic_cmpxchg(&state, RUNNING, TERMINATE);
244 qemu_notify_event();
245 }
246
247
248 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
249 const char *hostname)
250 {
251 int ret = EXIT_FAILURE;
252 int rc;
253 Error *err = NULL;
254 QIOChannelSocket *sioc;
255 NBDExportInfo *list;
256 int i, j;
257
258 sioc = qio_channel_socket_new();
259 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) {
260 error_report_err(err);
261 return EXIT_FAILURE;
262 }
263 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list,
264 &err);
265 if (rc < 0) {
266 if (err) {
267 error_report_err(err);
268 }
269 goto out;
270 }
271 printf("exports available: %d\n", rc);
272 for (i = 0; i < rc; i++) {
273 printf(" export: '%s'\n", list[i].name);
274 if (list[i].description && *list[i].description) {
275 printf(" description: %s\n", list[i].description);
276 }
277 if (list[i].flags & NBD_FLAG_HAS_FLAGS) {
278 printf(" size: %" PRIu64 "\n", list[i].size);
279 printf(" flags: 0x%x (", list[i].flags);
280 if (list[i].flags & NBD_FLAG_READ_ONLY) {
281 printf(" readonly");
282 }
283 if (list[i].flags & NBD_FLAG_SEND_FLUSH) {
284 printf(" flush");
285 }
286 if (list[i].flags & NBD_FLAG_SEND_FUA) {
287 printf(" fua");
288 }
289 if (list[i].flags & NBD_FLAG_ROTATIONAL) {
290 printf(" rotational");
291 }
292 if (list[i].flags & NBD_FLAG_SEND_TRIM) {
293 printf(" trim");
294 }
295 if (list[i].flags & NBD_FLAG_SEND_WRITE_ZEROES) {
296 printf(" zeroes");
297 }
298 if (list[i].flags & NBD_FLAG_SEND_DF) {
299 printf(" df");
300 }
301 if (list[i].flags & NBD_FLAG_CAN_MULTI_CONN) {
302 printf(" multi");
303 }
304 if (list[i].flags & NBD_FLAG_SEND_RESIZE) {
305 printf(" resize");
306 }
307 if (list[i].flags & NBD_FLAG_SEND_CACHE) {
308 printf(" cache");
309 }
310 printf(" )\n");
311 }
312 if (list[i].min_block) {
313 printf(" min block: %u\n", list[i].min_block);
314 printf(" opt block: %u\n", list[i].opt_block);
315 printf(" max block: %u\n", list[i].max_block);
316 }
317 if (list[i].n_contexts) {
318 printf(" available meta contexts: %d\n", list[i].n_contexts);
319 for (j = 0; j < list[i].n_contexts; j++) {
320 printf(" %s\n", list[i].contexts[j]);
321 }
322 }
323 }
324 nbd_free_export_list(list, rc);
325
326 ret = EXIT_SUCCESS;
327 out:
328 object_unref(OBJECT(sioc));
329 return ret;
330 }
331
332
333 #if HAVE_NBD_DEVICE
334 static void *show_parts(void *arg)
335 {
336 char *device = arg;
337 int nbd;
338
339 /* linux just needs an open() to trigger
340 * the partition table update
341 * but remember to load the module with max_part != 0 :
342 * modprobe nbd max_part=63
343 */
344 nbd = open(device, O_RDWR);
345 if (nbd >= 0) {
346 close(nbd);
347 }
348 return NULL;
349 }
350
351 static void *nbd_client_thread(void *arg)
352 {
353 char *device = arg;
354 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") };
355 QIOChannelSocket *sioc;
356 int fd;
357 int ret;
358 pthread_t show_parts_thread;
359 Error *local_error = NULL;
360
361 sioc = qio_channel_socket_new();
362 if (qio_channel_socket_connect_sync(sioc,
363 saddr,
364 &local_error) < 0) {
365 error_report_err(local_error);
366 goto out;
367 }
368
369 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc),
370 NULL, NULL, NULL, &info, &local_error);
371 if (ret < 0) {
372 if (local_error) {
373 error_report_err(local_error);
374 }
375 goto out_socket;
376 }
377
378 fd = open(device, O_RDWR);
379 if (fd < 0) {
380 /* Linux-only, we can use %m in printf. */
381 error_report("Failed to open %s: %m", device);
382 goto out_socket;
383 }
384
385 ret = nbd_init(fd, sioc, &info, &local_error);
386 if (ret < 0) {
387 error_report_err(local_error);
388 goto out_fd;
389 }
390
391 /* update partition table */
392 pthread_create(&show_parts_thread, NULL, show_parts, device);
393
394 if (verbose) {
395 fprintf(stderr, "NBD device %s is now connected to %s\n",
396 device, srcpath);
397 } else {
398 /* Close stderr so that the qemu-nbd process exits. */
399 dup2(STDOUT_FILENO, STDERR_FILENO);
400 }
401
402 ret = nbd_client(fd);
403 if (ret) {
404 goto out_fd;
405 }
406 close(fd);
407 object_unref(OBJECT(sioc));
408 g_free(info.name);
409 kill(getpid(), SIGTERM);
410 return (void *) EXIT_SUCCESS;
411
412 out_fd:
413 close(fd);
414 out_socket:
415 object_unref(OBJECT(sioc));
416 out:
417 g_free(info.name);
418 kill(getpid(), SIGTERM);
419 return (void *) EXIT_FAILURE;
420 }
421 #endif /* HAVE_NBD_DEVICE */
422
423 static int nbd_can_accept(void)
424 {
425 return state == RUNNING && nb_fds < shared;
426 }
427
428 static void nbd_export_closed(NBDExport *export)
429 {
430 assert(state == TERMINATING);
431 state = TERMINATED;
432 }
433
434 static void nbd_update_server_watch(void);
435
436 static void nbd_client_closed(NBDClient *client, bool negotiated)
437 {
438 nb_fds--;
439 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) {
440 state = TERMINATE;
441 }
442 nbd_update_server_watch();
443 nbd_client_put(client);
444 }
445
446 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc,
447 gpointer opaque)
448 {
449 if (state >= TERMINATE) {
450 return;
451 }
452
453 nb_fds++;
454 nbd_update_server_watch();
455 nbd_client_new(cioc, tlscreds, NULL, nbd_client_closed);
456 }
457
458 static void nbd_update_server_watch(void)
459 {
460 if (nbd_can_accept()) {
461 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL);
462 } else {
463 qio_net_listener_set_client_func(server, NULL, NULL, NULL);
464 }
465 }
466
467
468 static SocketAddress *nbd_build_socket_address(const char *sockpath,
469 const char *bindto,
470 const char *port)
471 {
472 SocketAddress *saddr;
473
474 saddr = g_new0(SocketAddress, 1);
475 if (sockpath) {
476 saddr->type = SOCKET_ADDRESS_TYPE_UNIX;
477 saddr->u.q_unix.path = g_strdup(sockpath);
478 } else {
479 InetSocketAddress *inet;
480 saddr->type = SOCKET_ADDRESS_TYPE_INET;
481 inet = &saddr->u.inet;
482 inet->host = g_strdup(bindto);
483 if (port) {
484 inet->port = g_strdup(port);
485 } else {
486 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
487 }
488 }
489
490 return saddr;
491 }
492
493
494 static QemuOptsList file_opts = {
495 .name = "file",
496 .implied_opt_name = "file",
497 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
498 .desc = {
499 /* no elements => accept any params */
500 { /* end of list */ }
501 },
502 };
503
504 static QemuOptsList qemu_object_opts = {
505 .name = "object",
506 .implied_opt_name = "qom-type",
507 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
508 .desc = {
509 { }
510 },
511 };
512
513
514
515 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
516 Error **errp)
517 {
518 Object *obj;
519 QCryptoTLSCreds *creds;
520
521 obj = object_resolve_path_component(
522 object_get_objects_root(), id);
523 if (!obj) {
524 error_setg(errp, "No TLS credentials with id '%s'",
525 id);
526 return NULL;
527 }
528 creds = (QCryptoTLSCreds *)
529 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
530 if (!creds) {
531 error_setg(errp, "Object with id '%s' is not TLS credentials",
532 id);
533 return NULL;
534 }
535
536 if (list) {
537 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
538 error_setg(errp,
539 "Expecting TLS credentials with a client endpoint");
540 return NULL;
541 }
542 } else {
543 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
544 error_setg(errp,
545 "Expecting TLS credentials with a server endpoint");
546 return NULL;
547 }
548 }
549 object_ref(obj);
550 return creds;
551 }
552
553 static void setup_address_and_port(const char **address, const char **port)
554 {
555 if (*address == NULL) {
556 *address = "0.0.0.0";
557 }
558
559 if (*port == NULL) {
560 *port = stringify(NBD_DEFAULT_PORT);
561 }
562 }
563
564 /*
565 * Check socket parameters compatibility when socket activation is used.
566 */
567 static const char *socket_activation_validate_opts(const char *device,
568 const char *sockpath,
569 const char *address,
570 const char *port,
571 bool list)
572 {
573 if (device != NULL) {
574 return "NBD device can't be set when using socket activation";
575 }
576
577 if (sockpath != NULL) {
578 return "Unix socket can't be set when using socket activation";
579 }
580
581 if (address != NULL) {
582 return "The interface can't be set when using socket activation";
583 }
584
585 if (port != NULL) {
586 return "TCP port number can't be set when using socket activation";
587 }
588
589 if (list) {
590 return "List mode is incompatible with socket activation";
591 }
592
593 return NULL;
594 }
595
596 static void qemu_nbd_shutdown(void)
597 {
598 job_cancel_sync_all();
599 bdrv_close_all();
600 }
601
602 int main(int argc, char **argv)
603 {
604 BlockBackend *blk;
605 BlockDriverState *bs;
606 uint64_t dev_offset = 0;
607 uint16_t nbdflags = 0;
608 bool disconnect = false;
609 const char *bindto = NULL;
610 const char *port = NULL;
611 char *sockpath = NULL;
612 char *device = NULL;
613 int64_t fd_size;
614 QemuOpts *sn_opts = NULL;
615 const char *sn_id_or_name = NULL;
616 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:L";
617 struct option lopt[] = {
618 { "help", no_argument, NULL, 'h' },
619 { "version", no_argument, NULL, 'V' },
620 { "bind", required_argument, NULL, 'b' },
621 { "port", required_argument, NULL, 'p' },
622 { "socket", required_argument, NULL, 'k' },
623 { "offset", required_argument, NULL, 'o' },
624 { "read-only", no_argument, NULL, 'r' },
625 { "partition", required_argument, NULL, 'P' },
626 { "bitmap", required_argument, NULL, 'B' },
627 { "connect", required_argument, NULL, 'c' },
628 { "disconnect", no_argument, NULL, 'd' },
629 { "list", no_argument, NULL, 'L' },
630 { "snapshot", no_argument, NULL, 's' },
631 { "load-snapshot", required_argument, NULL, 'l' },
632 { "nocache", no_argument, NULL, 'n' },
633 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
634 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
635 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
636 { "detect-zeroes", required_argument, NULL,
637 QEMU_NBD_OPT_DETECT_ZEROES },
638 { "shared", required_argument, NULL, 'e' },
639 { "format", required_argument, NULL, 'f' },
640 { "persistent", no_argument, NULL, 't' },
641 { "verbose", no_argument, NULL, 'v' },
642 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
643 { "export-name", required_argument, NULL, 'x' },
644 { "description", required_argument, NULL, 'D' },
645 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
646 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
647 { "trace", required_argument, NULL, 'T' },
648 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
649 { NULL, 0, NULL, 0 }
650 };
651 int ch;
652 int opt_ind = 0;
653 int flags = BDRV_O_RDWR;
654 int partition = 0;
655 int ret = 0;
656 bool seen_cache = false;
657 bool seen_discard = false;
658 bool seen_aio = false;
659 pthread_t client_thread;
660 const char *fmt = NULL;
661 Error *local_err = NULL;
662 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
663 QDict *options = NULL;
664 const char *export_name = NULL; /* defaults to "" later for server mode */
665 const char *export_description = NULL;
666 const char *bitmap = NULL;
667 const char *tlscredsid = NULL;
668 bool imageOpts = false;
669 bool writethrough = true;
670 char *trace_file = NULL;
671 bool fork_process = false;
672 bool list = false;
673 int old_stderr = -1;
674 unsigned socket_activation;
675
676 /* The client thread uses SIGTERM to interrupt the server. A signal
677 * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
678 */
679 struct sigaction sa_sigterm;
680 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
681 sa_sigterm.sa_handler = termsig_handler;
682 sigaction(SIGTERM, &sa_sigterm, NULL);
683
684 #ifdef CONFIG_POSIX
685 signal(SIGPIPE, SIG_IGN);
686 #endif
687
688 module_call_init(MODULE_INIT_TRACE);
689 error_set_progname(argv[0]);
690 qcrypto_init(&error_fatal);
691
692 module_call_init(MODULE_INIT_QOM);
693 qemu_add_opts(&qemu_object_opts);
694 qemu_add_opts(&qemu_trace_opts);
695 qemu_init_exec_dir(argv[0]);
696
697 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
698 switch (ch) {
699 case 's':
700 flags |= BDRV_O_SNAPSHOT;
701 break;
702 case 'n':
703 optarg = (char *) "none";
704 /* fallthrough */
705 case QEMU_NBD_OPT_CACHE:
706 if (seen_cache) {
707 error_report("-n and --cache can only be specified once");
708 exit(EXIT_FAILURE);
709 }
710 seen_cache = true;
711 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
712 error_report("Invalid cache mode `%s'", optarg);
713 exit(EXIT_FAILURE);
714 }
715 break;
716 case QEMU_NBD_OPT_AIO:
717 if (seen_aio) {
718 error_report("--aio can only be specified once");
719 exit(EXIT_FAILURE);
720 }
721 seen_aio = true;
722 if (!strcmp(optarg, "native")) {
723 flags |= BDRV_O_NATIVE_AIO;
724 } else if (!strcmp(optarg, "threads")) {
725 /* this is the default */
726 } else {
727 error_report("invalid aio mode `%s'", optarg);
728 exit(EXIT_FAILURE);
729 }
730 break;
731 case QEMU_NBD_OPT_DISCARD:
732 if (seen_discard) {
733 error_report("--discard can only be specified once");
734 exit(EXIT_FAILURE);
735 }
736 seen_discard = true;
737 if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
738 error_report("Invalid discard mode `%s'", optarg);
739 exit(EXIT_FAILURE);
740 }
741 break;
742 case QEMU_NBD_OPT_DETECT_ZEROES:
743 detect_zeroes =
744 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
745 optarg,
746 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
747 &local_err);
748 if (local_err) {
749 error_reportf_err(local_err,
750 "Failed to parse detect_zeroes mode: ");
751 exit(EXIT_FAILURE);
752 }
753 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
754 !(flags & BDRV_O_UNMAP)) {
755 error_report("setting detect-zeroes to unmap is not allowed "
756 "without setting discard operation to unmap");
757 exit(EXIT_FAILURE);
758 }
759 break;
760 case 'b':
761 bindto = optarg;
762 break;
763 case 'p':
764 port = optarg;
765 break;
766 case 'o':
767 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) {
768 error_report("Invalid offset '%s'", optarg);
769 exit(EXIT_FAILURE);
770 }
771 break;
772 case 'l':
773 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
774 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
775 optarg, false);
776 if (!sn_opts) {
777 error_report("Failed in parsing snapshot param `%s'",
778 optarg);
779 exit(EXIT_FAILURE);
780 }
781 } else {
782 sn_id_or_name = optarg;
783 }
784 /* fall through */
785 case 'r':
786 nbdflags |= NBD_FLAG_READ_ONLY;
787 flags &= ~BDRV_O_RDWR;
788 break;
789 case 'P':
790 warn_report("The '-P' option is deprecated; use --image-opts with "
791 "a raw device wrapper for subset exports instead");
792 if (qemu_strtoi(optarg, NULL, 0, &partition) < 0 ||
793 partition < 1 || partition > 8) {
794 error_report("Invalid partition '%s'", optarg);
795 exit(EXIT_FAILURE);
796 }
797 break;
798 case 'B':
799 bitmap = optarg;
800 break;
801 case 'k':
802 sockpath = optarg;
803 if (sockpath[0] != '/') {
804 error_report("socket path must be absolute");
805 exit(EXIT_FAILURE);
806 }
807 break;
808 case 'd':
809 disconnect = true;
810 break;
811 case 'c':
812 device = optarg;
813 break;
814 case 'e':
815 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 ||
816 shared < 1) {
817 error_report("Invalid shared device number '%s'", optarg);
818 exit(EXIT_FAILURE);
819 }
820 break;
821 case 'f':
822 fmt = optarg;
823 break;
824 case 't':
825 persistent = 1;
826 break;
827 case 'x':
828 export_name = optarg;
829 break;
830 case 'D':
831 export_description = optarg;
832 break;
833 case 'v':
834 verbose = 1;
835 break;
836 case 'V':
837 version(argv[0]);
838 exit(0);
839 break;
840 case 'h':
841 usage(argv[0]);
842 exit(0);
843 break;
844 case '?':
845 error_report("Try `%s --help' for more information.", argv[0]);
846 exit(EXIT_FAILURE);
847 case QEMU_NBD_OPT_OBJECT: {
848 QemuOpts *opts;
849 opts = qemu_opts_parse_noisily(&qemu_object_opts,
850 optarg, true);
851 if (!opts) {
852 exit(EXIT_FAILURE);
853 }
854 } break;
855 case QEMU_NBD_OPT_TLSCREDS:
856 tlscredsid = optarg;
857 break;
858 case QEMU_NBD_OPT_IMAGE_OPTS:
859 imageOpts = true;
860 break;
861 case 'T':
862 g_free(trace_file);
863 trace_file = trace_opt_parse(optarg);
864 break;
865 case QEMU_NBD_OPT_FORK:
866 fork_process = true;
867 break;
868 case 'L':
869 list = true;
870 break;
871 }
872 }
873
874 if (list) {
875 if (argc != optind) {
876 error_report("List mode is incompatible with a file name");
877 exit(EXIT_FAILURE);
878 }
879 if (export_name || export_description || dev_offset || partition ||
880 device || disconnect || fmt || sn_id_or_name || bitmap ||
881 seen_aio || seen_discard || seen_cache) {
882 error_report("List mode is incompatible with per-device settings");
883 exit(EXIT_FAILURE);
884 }
885 if (fork_process) {
886 error_report("List mode is incompatible with forking");
887 exit(EXIT_FAILURE);
888 }
889 } else if ((argc - optind) != 1) {
890 error_report("Invalid number of arguments");
891 error_printf("Try `%s --help' for more information.\n", argv[0]);
892 exit(EXIT_FAILURE);
893 } else if (!export_name) {
894 export_name = "";
895 }
896
897 qemu_opts_foreach(&qemu_object_opts,
898 user_creatable_add_opts_foreach,
899 NULL, &error_fatal);
900
901 if (!trace_init_backends()) {
902 exit(1);
903 }
904 trace_init_file(trace_file);
905 qemu_set_log(LOG_TRACE);
906
907 socket_activation = check_socket_activation();
908 if (socket_activation == 0) {
909 setup_address_and_port(&bindto, &port);
910 } else {
911 /* Using socket activation - check user didn't use -p etc. */
912 const char *err_msg = socket_activation_validate_opts(device, sockpath,
913 bindto, port,
914 list);
915 if (err_msg != NULL) {
916 error_report("%s", err_msg);
917 exit(EXIT_FAILURE);
918 }
919
920 /* qemu-nbd can only listen on a single socket. */
921 if (socket_activation > 1) {
922 error_report("qemu-nbd does not support socket activation with %s > 1",
923 "LISTEN_FDS");
924 exit(EXIT_FAILURE);
925 }
926 }
927
928 if (tlscredsid) {
929 if (sockpath) {
930 error_report("TLS is only supported with IPv4/IPv6");
931 exit(EXIT_FAILURE);
932 }
933 if (device) {
934 error_report("TLS is not supported with a host device");
935 exit(EXIT_FAILURE);
936 }
937 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err);
938 if (local_err) {
939 error_report("Failed to get TLS creds %s",
940 error_get_pretty(local_err));
941 exit(EXIT_FAILURE);
942 }
943 }
944
945 if (list) {
946 saddr = nbd_build_socket_address(sockpath, bindto, port);
947 return qemu_nbd_client_list(saddr, tlscreds, bindto);
948 }
949
950 #if !HAVE_NBD_DEVICE
951 if (disconnect || device) {
952 error_report("Kernel /dev/nbdN support not available");
953 exit(EXIT_FAILURE);
954 }
955 #else /* HAVE_NBD_DEVICE */
956 if (disconnect) {
957 int nbdfd = open(argv[optind], O_RDWR);
958 if (nbdfd < 0) {
959 error_report("Cannot open %s: %s", argv[optind],
960 strerror(errno));
961 exit(EXIT_FAILURE);
962 }
963 nbd_disconnect(nbdfd);
964
965 close(nbdfd);
966
967 printf("%s disconnected\n", argv[optind]);
968
969 return 0;
970 }
971 #endif
972
973 if ((device && !verbose) || fork_process) {
974 int stderr_fd[2];
975 pid_t pid;
976 int ret;
977
978 if (qemu_pipe(stderr_fd) < 0) {
979 error_report("Error setting up communication pipe: %s",
980 strerror(errno));
981 exit(EXIT_FAILURE);
982 }
983
984 /* Now daemonize, but keep a communication channel open to
985 * print errors and exit with the proper status code.
986 */
987 pid = fork();
988 if (pid < 0) {
989 error_report("Failed to fork: %s", strerror(errno));
990 exit(EXIT_FAILURE);
991 } else if (pid == 0) {
992 close(stderr_fd[0]);
993 ret = qemu_daemon(1, 0);
994
995 /* Temporarily redirect stderr to the parent's pipe... */
996 old_stderr = dup(STDERR_FILENO);
997 dup2(stderr_fd[1], STDERR_FILENO);
998 if (ret < 0) {
999 error_report("Failed to daemonize: %s", strerror(errno));
1000 exit(EXIT_FAILURE);
1001 }
1002
1003 /* ... close the descriptor we inherited and go on. */
1004 close(stderr_fd[1]);
1005 } else {
1006 bool errors = false;
1007 char *buf;
1008
1009 /* In the parent. Print error messages from the child until
1010 * it closes the pipe.
1011 */
1012 close(stderr_fd[1]);
1013 buf = g_malloc(1024);
1014 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
1015 errors = true;
1016 ret = qemu_write_full(STDERR_FILENO, buf, ret);
1017 if (ret < 0) {
1018 exit(EXIT_FAILURE);
1019 }
1020 }
1021 if (ret < 0) {
1022 error_report("Cannot read from daemon: %s",
1023 strerror(errno));
1024 exit(EXIT_FAILURE);
1025 }
1026
1027 /* Usually the daemon should not print any message.
1028 * Exit with zero status in that case.
1029 */
1030 exit(errors);
1031 }
1032 }
1033
1034 if (device != NULL && sockpath == NULL) {
1035 sockpath = g_malloc(128);
1036 snprintf(sockpath, 128, SOCKET_PATH, basename(device));
1037 }
1038
1039 server = qio_net_listener_new();
1040 if (socket_activation == 0) {
1041 saddr = nbd_build_socket_address(sockpath, bindto, port);
1042 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) {
1043 object_unref(OBJECT(server));
1044 error_report_err(local_err);
1045 exit(EXIT_FAILURE);
1046 }
1047 } else {
1048 size_t i;
1049 /* See comment in check_socket_activation above. */
1050 for (i = 0; i < socket_activation; i++) {
1051 QIOChannelSocket *sioc;
1052 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i,
1053 &local_err);
1054 if (sioc == NULL) {
1055 object_unref(OBJECT(server));
1056 error_report("Failed to use socket activation: %s",
1057 error_get_pretty(local_err));
1058 exit(EXIT_FAILURE);
1059 }
1060 qio_net_listener_add(server, sioc);
1061 object_unref(OBJECT(sioc));
1062 }
1063 }
1064
1065 if (qemu_init_main_loop(&local_err)) {
1066 error_report_err(local_err);
1067 exit(EXIT_FAILURE);
1068 }
1069 bdrv_init();
1070 atexit(qemu_nbd_shutdown);
1071
1072 srcpath = argv[optind];
1073 if (imageOpts) {
1074 QemuOpts *opts;
1075 if (fmt) {
1076 error_report("--image-opts and -f are mutually exclusive");
1077 exit(EXIT_FAILURE);
1078 }
1079 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
1080 if (!opts) {
1081 qemu_opts_reset(&file_opts);
1082 exit(EXIT_FAILURE);
1083 }
1084 options = qemu_opts_to_qdict(opts, NULL);
1085 qemu_opts_reset(&file_opts);
1086 blk = blk_new_open(NULL, NULL, options, flags, &local_err);
1087 } else {
1088 if (fmt) {
1089 options = qdict_new();
1090 qdict_put_str(options, "driver", fmt);
1091 }
1092 blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
1093 }
1094
1095 if (!blk) {
1096 error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
1097 argv[optind]);
1098 exit(EXIT_FAILURE);
1099 }
1100 bs = blk_bs(blk);
1101
1102 blk_set_enable_write_cache(blk, !writethrough);
1103
1104 if (sn_opts) {
1105 ret = bdrv_snapshot_load_tmp(bs,
1106 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
1107 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
1108 &local_err);
1109 } else if (sn_id_or_name) {
1110 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
1111 &local_err);
1112 }
1113 if (ret < 0) {
1114 error_reportf_err(local_err, "Failed to load snapshot: ");
1115 exit(EXIT_FAILURE);
1116 }
1117
1118 bs->detect_zeroes = detect_zeroes;
1119 fd_size = blk_getlength(blk);
1120 if (fd_size < 0) {
1121 error_report("Failed to determine the image length: %s",
1122 strerror(-fd_size));
1123 exit(EXIT_FAILURE);
1124 }
1125
1126 if (dev_offset >= fd_size) {
1127 error_report("Offset (%" PRIu64 ") has to be smaller than the image "
1128 "size (%" PRId64 ")", dev_offset, fd_size);
1129 exit(EXIT_FAILURE);
1130 }
1131 fd_size -= dev_offset;
1132
1133 if (partition) {
1134 uint64_t limit;
1135
1136 if (dev_offset) {
1137 error_report("Cannot request partition and offset together");
1138 exit(EXIT_FAILURE);
1139 }
1140 ret = find_partition(blk, partition, &dev_offset, &limit);
1141 if (ret < 0) {
1142 error_report("Could not find partition %d: %s", partition,
1143 strerror(-ret));
1144 exit(EXIT_FAILURE);
1145 }
1146 /*
1147 * MBR partition limits are (32-bit << 9); this assert lets
1148 * the compiler know that we can't overflow 64 bits.
1149 */
1150 assert(dev_offset + limit >= dev_offset);
1151 if (dev_offset + limit > fd_size) {
1152 error_report("Discovered partition %d at offset %" PRIu64
1153 " size %" PRIu64 ", but size exceeds file length %"
1154 PRId64, partition, dev_offset, limit, fd_size);
1155 exit(EXIT_FAILURE);
1156 }
1157 fd_size = limit;
1158 }
1159
1160 export = nbd_export_new(bs, dev_offset, fd_size, export_name,
1161 export_description, bitmap, nbdflags,
1162 nbd_export_closed, writethrough, NULL,
1163 &error_fatal);
1164
1165 if (device) {
1166 #if HAVE_NBD_DEVICE
1167 int ret;
1168
1169 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
1170 if (ret != 0) {
1171 error_report("Failed to create client thread: %s", strerror(ret));
1172 exit(EXIT_FAILURE);
1173 }
1174 #endif
1175 } else {
1176 /* Shut up GCC warnings. */
1177 memset(&client_thread, 0, sizeof(client_thread));
1178 }
1179
1180 nbd_update_server_watch();
1181
1182 /* now when the initialization is (almost) complete, chdir("/")
1183 * to free any busy filesystems */
1184 if (chdir("/") < 0) {
1185 error_report("Could not chdir to root directory: %s",
1186 strerror(errno));
1187 exit(EXIT_FAILURE);
1188 }
1189
1190 if (fork_process) {
1191 dup2(old_stderr, STDERR_FILENO);
1192 close(old_stderr);
1193 }
1194
1195 state = RUNNING;
1196 do {
1197 main_loop_wait(false);
1198 if (state == TERMINATE) {
1199 state = TERMINATING;
1200 nbd_export_close(export);
1201 nbd_export_put(export);
1202 export = NULL;
1203 }
1204 } while (state != TERMINATED);
1205
1206 blk_unref(blk);
1207 if (sockpath) {
1208 unlink(sockpath);
1209 }
1210
1211 qemu_opts_del(sn_opts);
1212
1213 if (device) {
1214 void *ret;
1215 pthread_join(client_thread, &ret);
1216 exit(ret != NULL);
1217 } else {
1218 exit(EXIT_SUCCESS);
1219 }
1220 }
armbru's QEMU hackery