2 * Copyright (C) 2016-2018 Red Hat, Inc.
3 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
5 * Network Block Device Server Side
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; under version 2 of the License.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 #include "qemu/osdep.h"
21 #include "qapi/error.h"
23 #include "nbd-internal.h"
25 static int system_errno_to_nbd_errno(int err
)
53 /* Definitions for opaque data types */
55 typedef struct NBDRequestData NBDRequestData
;
57 struct NBDRequestData
{
58 QSIMPLEQ_ENTRY(NBDRequestData
) entry
;
66 void (*close
)(NBDExport
*exp
);
74 QTAILQ_HEAD(, NBDClient
) clients
;
75 QTAILQ_ENTRY(NBDExport
) next
;
79 BlockBackend
*eject_notifier_blk
;
80 Notifier eject_notifier
;
83 static QTAILQ_HEAD(, NBDExport
) exports
= QTAILQ_HEAD_INITIALIZER(exports
);
87 void (*close_fn
)(NBDClient
*client
, bool negotiated
);
90 QCryptoTLSCreds
*tlscreds
;
92 QIOChannelSocket
*sioc
; /* The underlying data channel */
93 QIOChannel
*ioc
; /* The current I/O channel which may differ (eg TLS) */
95 Coroutine
*recv_coroutine
;
98 Coroutine
*send_coroutine
;
100 QTAILQ_ENTRY(NBDClient
) next
;
104 bool structured_reply
;
106 uint32_t opt
; /* Current option being negotiated */
107 uint32_t optlen
; /* remaining length of data in ioc for the option being
111 static void nbd_client_receive_next_request(NBDClient
*client
);
113 /* Basic flow for negotiation
140 static inline void set_be_option_rep(NBDOptionReply
*rep
, uint32_t option
,
141 uint32_t type
, uint32_t length
)
143 stq_be_p(&rep
->magic
, NBD_REP_MAGIC
);
144 stl_be_p(&rep
->option
, option
);
145 stl_be_p(&rep
->type
, type
);
146 stl_be_p(&rep
->length
, length
);
149 /* Send a reply header, including length, but no payload.
150 * Return -errno on error, 0 on success. */
151 static int nbd_negotiate_send_rep_len(NBDClient
*client
, uint32_t type
,
152 uint32_t len
, Error
**errp
)
156 trace_nbd_negotiate_send_rep_len(client
->opt
, nbd_opt_lookup(client
->opt
),
157 type
, nbd_rep_lookup(type
), len
);
159 assert(len
< NBD_MAX_BUFFER_SIZE
);
161 set_be_option_rep(&rep
, client
->opt
, type
, len
);
162 return nbd_write(client
->ioc
, &rep
, sizeof(rep
), errp
);
165 /* Send a reply header with default 0 length.
166 * Return -errno on error, 0 on success. */
167 static int nbd_negotiate_send_rep(NBDClient
*client
, uint32_t type
,
170 return nbd_negotiate_send_rep_len(client
, type
, 0, errp
);
173 /* Send an error reply.
174 * Return -errno on error, 0 on success. */
175 static int GCC_FMT_ATTR(4, 0)
176 nbd_negotiate_send_rep_verr(NBDClient
*client
, uint32_t type
,
177 Error
**errp
, const char *fmt
, va_list va
)
183 msg
= g_strdup_vprintf(fmt
, va
);
186 trace_nbd_negotiate_send_rep_err(msg
);
187 ret
= nbd_negotiate_send_rep_len(client
, type
, len
, errp
);
191 if (nbd_write(client
->ioc
, msg
, len
, errp
) < 0) {
192 error_prepend(errp
, "write failed (error message): ");
203 /* Send an error reply.
204 * Return -errno on error, 0 on success. */
205 static int GCC_FMT_ATTR(4, 5)
206 nbd_negotiate_send_rep_err(NBDClient
*client
, uint32_t type
,
207 Error
**errp
, const char *fmt
, ...)
213 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
218 /* Drop remainder of the current option, and send a reply with the
219 * given error type and message. Return -errno on read or write
220 * failure; or 0 if connection is still live. */
221 static int GCC_FMT_ATTR(4, 5)
222 nbd_opt_drop(NBDClient
*client
, uint32_t type
, Error
**errp
,
223 const char *fmt
, ...)
225 int ret
= nbd_drop(client
->ioc
, client
->optlen
, errp
);
231 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
237 /* Read size bytes from the unparsed payload of the current option.
238 * Return -errno on I/O error, 0 if option was completely handled by
239 * sending a reply about inconsistent lengths, or 1 on success. */
240 static int nbd_opt_read(NBDClient
*client
, void *buffer
, size_t size
,
243 if (size
> client
->optlen
) {
244 return nbd_opt_drop(client
, NBD_REP_ERR_INVALID
, errp
,
245 "Inconsistent lengths in option %s",
246 nbd_opt_lookup(client
->opt
));
248 client
->optlen
-= size
;
249 return qio_channel_read_all(client
->ioc
, buffer
, size
, errp
) < 0 ? -EIO
: 1;
252 /* Send a single NBD_REP_SERVER reply to NBD_OPT_LIST, including payload.
253 * Return -errno on error, 0 on success. */
254 static int nbd_negotiate_send_rep_list(NBDClient
*client
, NBDExport
*exp
,
257 size_t name_len
, desc_len
;
259 const char *name
= exp
->name
? exp
->name
: "";
260 const char *desc
= exp
->description
? exp
->description
: "";
261 QIOChannel
*ioc
= client
->ioc
;
264 trace_nbd_negotiate_send_rep_list(name
, desc
);
265 name_len
= strlen(name
);
266 desc_len
= strlen(desc
);
267 len
= name_len
+ desc_len
+ sizeof(len
);
268 ret
= nbd_negotiate_send_rep_len(client
, NBD_REP_SERVER
, len
, errp
);
273 len
= cpu_to_be32(name_len
);
274 if (nbd_write(ioc
, &len
, sizeof(len
), errp
) < 0) {
275 error_prepend(errp
, "write failed (name length): ");
279 if (nbd_write(ioc
, name
, name_len
, errp
) < 0) {
280 error_prepend(errp
, "write failed (name buffer): ");
284 if (nbd_write(ioc
, desc
, desc_len
, errp
) < 0) {
285 error_prepend(errp
, "write failed (description buffer): ");
292 /* Process the NBD_OPT_LIST command, with a potential series of replies.
293 * Return -errno on error, 0 on success. */
294 static int nbd_negotiate_handle_list(NBDClient
*client
, Error
**errp
)
297 assert(client
->opt
== NBD_OPT_LIST
);
299 /* For each export, send a NBD_REP_SERVER reply. */
300 QTAILQ_FOREACH(exp
, &exports
, next
) {
301 if (nbd_negotiate_send_rep_list(client
, exp
, errp
)) {
305 /* Finish with a NBD_REP_ACK. */
306 return nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
309 /* Send a reply to NBD_OPT_EXPORT_NAME.
310 * Return -errno on error, 0 on success. */
311 static int nbd_negotiate_handle_export_name(NBDClient
*client
,
312 uint16_t myflags
, bool no_zeroes
,
315 char name
[NBD_MAX_NAME_SIZE
+ 1];
316 char buf
[NBD_REPLY_EXPORT_NAME_SIZE
] = "";
321 [20 .. xx] export name (length bytes)
324 [ 8 .. 9] export flags
325 [10 .. 133] reserved (0) [unless no_zeroes]
327 trace_nbd_negotiate_handle_export_name();
328 if (client
->optlen
>= sizeof(name
)) {
329 error_setg(errp
, "Bad length received");
332 if (nbd_read(client
->ioc
, name
, client
->optlen
, errp
) < 0) {
333 error_prepend(errp
, "read failed: ");
336 name
[client
->optlen
] = '\0';
339 trace_nbd_negotiate_handle_export_name_request(name
);
341 client
->exp
= nbd_export_find(name
);
343 error_setg(errp
, "export not found");
347 trace_nbd_negotiate_new_style_size_flags(client
->exp
->size
,
348 client
->exp
->nbdflags
| myflags
);
349 stq_be_p(buf
, client
->exp
->size
);
350 stw_be_p(buf
+ 8, client
->exp
->nbdflags
| myflags
);
351 len
= no_zeroes
? 10 : sizeof(buf
);
352 ret
= nbd_write(client
->ioc
, buf
, len
, errp
);
354 error_prepend(errp
, "write failed: ");
358 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
359 nbd_export_get(client
->exp
);
364 /* Send a single NBD_REP_INFO, with a buffer @buf of @length bytes.
365 * The buffer does NOT include the info type prefix.
366 * Return -errno on error, 0 if ready to send more. */
367 static int nbd_negotiate_send_info(NBDClient
*client
,
368 uint16_t info
, uint32_t length
, void *buf
,
373 trace_nbd_negotiate_send_info(info
, nbd_info_lookup(info
), length
);
374 rc
= nbd_negotiate_send_rep_len(client
, NBD_REP_INFO
,
375 sizeof(info
) + length
, errp
);
380 if (nbd_write(client
->ioc
, &info
, sizeof(info
), errp
) < 0) {
383 if (nbd_write(client
->ioc
, buf
, length
, errp
) < 0) {
389 /* nbd_reject_length: Handle any unexpected payload.
390 * @fatal requests that we quit talking to the client, even if we are able
391 * to successfully send an error reply.
393 * -errno transmission error occurred or @fatal was requested, errp is set
394 * 0 error message successfully sent to client, errp is not set
396 static int nbd_reject_length(NBDClient
*client
, bool fatal
, Error
**errp
)
400 assert(client
->optlen
);
401 ret
= nbd_opt_drop(client
, NBD_REP_ERR_INVALID
, errp
,
402 "option '%s' has unexpected length",
403 nbd_opt_lookup(client
->opt
));
405 error_setg(errp
, "option '%s' has unexpected length",
406 nbd_opt_lookup(client
->opt
));
412 /* Handle NBD_OPT_INFO and NBD_OPT_GO.
413 * Return -errno on error, 0 if ready for next option, and 1 to move
414 * into transmission phase. */
415 static int nbd_negotiate_handle_info(NBDClient
*client
, uint16_t myflags
,
419 char name
[NBD_MAX_NAME_SIZE
+ 1];
424 bool sendname
= false;
425 bool blocksize
= false;
427 char buf
[sizeof(uint64_t) + sizeof(uint16_t)];
430 4 bytes: L, name length (can be 0)
432 2 bytes: N, number of requests (can be 0)
433 N * 2 bytes: N requests
435 rc
= nbd_opt_read(client
, &namelen
, sizeof(namelen
), errp
);
439 be32_to_cpus(&namelen
);
440 if (namelen
>= sizeof(name
)) {
441 return nbd_opt_drop(client
, NBD_REP_ERR_INVALID
, errp
,
442 "name too long for qemu");
444 rc
= nbd_opt_read(client
, name
, namelen
, errp
);
448 name
[namelen
] = '\0';
449 trace_nbd_negotiate_handle_export_name_request(name
);
451 rc
= nbd_opt_read(client
, &requests
, sizeof(requests
), errp
);
455 be16_to_cpus(&requests
);
456 trace_nbd_negotiate_handle_info_requests(requests
);
458 rc
= nbd_opt_read(client
, &request
, sizeof(request
), errp
);
462 be16_to_cpus(&request
);
463 trace_nbd_negotiate_handle_info_request(request
,
464 nbd_info_lookup(request
));
465 /* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE;
466 * everything else is either a request we don't know or
467 * something we send regardless of request */
472 case NBD_INFO_BLOCK_SIZE
:
477 if (client
->optlen
) {
478 return nbd_reject_length(client
, false, errp
);
481 exp
= nbd_export_find(name
);
483 return nbd_negotiate_send_rep_err(client
, NBD_REP_ERR_UNKNOWN
,
484 errp
, "export '%s' not present",
488 /* Don't bother sending NBD_INFO_NAME unless client requested it */
490 rc
= nbd_negotiate_send_info(client
, NBD_INFO_NAME
, namelen
, name
,
497 /* Send NBD_INFO_DESCRIPTION only if available, regardless of
499 if (exp
->description
) {
500 size_t len
= strlen(exp
->description
);
502 rc
= nbd_negotiate_send_info(client
, NBD_INFO_DESCRIPTION
,
503 len
, exp
->description
, errp
);
509 /* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
510 * according to whether the client requested it, and according to
511 * whether this is OPT_INFO or OPT_GO. */
512 /* minimum - 1 for back-compat, or 512 if client is new enough.
513 * TODO: consult blk_bs(blk)->bl.request_alignment? */
515 (client
->opt
== NBD_OPT_INFO
|| blocksize
) ? BDRV_SECTOR_SIZE
: 1;
516 /* preferred - Hard-code to 4096 for now.
517 * TODO: is blk_bs(blk)->bl.opt_transfer appropriate? */
519 /* maximum - At most 32M, but smaller as appropriate. */
520 sizes
[2] = MIN(blk_get_max_transfer(exp
->blk
), NBD_MAX_BUFFER_SIZE
);
521 trace_nbd_negotiate_handle_info_block_size(sizes
[0], sizes
[1], sizes
[2]);
522 cpu_to_be32s(&sizes
[0]);
523 cpu_to_be32s(&sizes
[1]);
524 cpu_to_be32s(&sizes
[2]);
525 rc
= nbd_negotiate_send_info(client
, NBD_INFO_BLOCK_SIZE
,
526 sizeof(sizes
), sizes
, errp
);
531 /* Send NBD_INFO_EXPORT always */
532 trace_nbd_negotiate_new_style_size_flags(exp
->size
,
533 exp
->nbdflags
| myflags
);
534 stq_be_p(buf
, exp
->size
);
535 stw_be_p(buf
+ 8, exp
->nbdflags
| myflags
);
536 rc
= nbd_negotiate_send_info(client
, NBD_INFO_EXPORT
,
537 sizeof(buf
), buf
, errp
);
542 /* If the client is just asking for NBD_OPT_INFO, but forgot to
543 * request block sizes, return an error.
544 * TODO: consult blk_bs(blk)->request_align, and only error if it
546 if (client
->opt
== NBD_OPT_INFO
&& !blocksize
) {
547 return nbd_negotiate_send_rep_err(client
,
548 NBD_REP_ERR_BLOCK_SIZE_REQD
,
550 "request NBD_INFO_BLOCK_SIZE to "
555 rc
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
560 if (client
->opt
== NBD_OPT_GO
) {
562 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
563 nbd_export_get(client
->exp
);
570 /* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the
571 * new channel for all further (now-encrypted) communication. */
572 static QIOChannel
*nbd_negotiate_handle_starttls(NBDClient
*client
,
577 struct NBDTLSHandshakeData data
= { 0 };
579 assert(client
->opt
== NBD_OPT_STARTTLS
);
581 trace_nbd_negotiate_handle_starttls();
584 if (nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
) < 0) {
588 tioc
= qio_channel_tls_new_server(ioc
,
596 qio_channel_set_name(QIO_CHANNEL(tioc
), "nbd-server-tls");
597 trace_nbd_negotiate_handle_starttls_handshake();
598 data
.loop
= g_main_loop_new(g_main_context_default(), FALSE
);
599 qio_channel_tls_handshake(tioc
,
605 if (!data
.complete
) {
606 g_main_loop_run(data
.loop
);
608 g_main_loop_unref(data
.loop
);
610 object_unref(OBJECT(tioc
));
611 error_propagate(errp
, data
.error
);
615 return QIO_CHANNEL(tioc
);
618 /* nbd_negotiate_options
619 * Process all NBD_OPT_* client option commands, during fixed newstyle
622 * -errno on error, errp is set
623 * 0 on successful negotiation, errp is not set
624 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
627 static int nbd_negotiate_options(NBDClient
*client
, uint16_t myflags
,
631 bool fixedNewstyle
= false;
632 bool no_zeroes
= false;
635 [ 0 .. 3] client flags
637 Then we loop until NBD_OPT_EXPORT_NAME or NBD_OPT_GO:
638 [ 0 .. 7] NBD_OPTS_MAGIC
639 [ 8 .. 11] NBD option
640 [12 .. 15] Data length
643 [ 0 .. 7] NBD_OPTS_MAGIC
644 [ 8 .. 11] Second NBD option
645 [12 .. 15] Data length
649 if (nbd_read(client
->ioc
, &flags
, sizeof(flags
), errp
) < 0) {
650 error_prepend(errp
, "read failed: ");
653 be32_to_cpus(&flags
);
654 trace_nbd_negotiate_options_flags(flags
);
655 if (flags
& NBD_FLAG_C_FIXED_NEWSTYLE
) {
656 fixedNewstyle
= true;
657 flags
&= ~NBD_FLAG_C_FIXED_NEWSTYLE
;
659 if (flags
& NBD_FLAG_C_NO_ZEROES
) {
661 flags
&= ~NBD_FLAG_C_NO_ZEROES
;
664 error_setg(errp
, "Unknown client flags 0x%" PRIx32
" received", flags
);
670 uint32_t option
, length
;
673 if (nbd_read(client
->ioc
, &magic
, sizeof(magic
), errp
) < 0) {
674 error_prepend(errp
, "read failed: ");
677 magic
= be64_to_cpu(magic
);
678 trace_nbd_negotiate_options_check_magic(magic
);
679 if (magic
!= NBD_OPTS_MAGIC
) {
680 error_setg(errp
, "Bad magic received");
684 if (nbd_read(client
->ioc
, &option
,
685 sizeof(option
), errp
) < 0) {
686 error_prepend(errp
, "read failed: ");
689 option
= be32_to_cpu(option
);
690 client
->opt
= option
;
692 if (nbd_read(client
->ioc
, &length
, sizeof(length
), errp
) < 0) {
693 error_prepend(errp
, "read failed: ");
696 length
= be32_to_cpu(length
);
697 assert(!client
->optlen
);
698 client
->optlen
= length
;
700 if (length
> NBD_MAX_BUFFER_SIZE
) {
701 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
702 length
, NBD_MAX_BUFFER_SIZE
);
706 trace_nbd_negotiate_options_check_option(option
,
707 nbd_opt_lookup(option
));
708 if (client
->tlscreds
&&
709 client
->ioc
== (QIOChannel
*)client
->sioc
) {
711 if (!fixedNewstyle
) {
712 error_setg(errp
, "Unsupported option 0x%" PRIx32
, option
);
716 case NBD_OPT_STARTTLS
:
718 /* Unconditionally drop the connection if the client
719 * can't start a TLS negotiation correctly */
720 return nbd_reject_length(client
, true, errp
);
722 tioc
= nbd_negotiate_handle_starttls(client
, errp
);
727 object_unref(OBJECT(client
->ioc
));
728 client
->ioc
= QIO_CHANNEL(tioc
);
731 case NBD_OPT_EXPORT_NAME
:
732 /* No way to return an error to client, so drop connection */
733 error_setg(errp
, "Option 0x%x not permitted before TLS",
738 ret
= nbd_opt_drop(client
, NBD_REP_ERR_TLS_REQD
, errp
,
740 "not permitted before TLS", option
);
741 /* Let the client keep trying, unless they asked to
742 * quit. In this mode, we've already sent an error, so
743 * we can't ack the abort. */
744 if (option
== NBD_OPT_ABORT
) {
749 } else if (fixedNewstyle
) {
753 ret
= nbd_reject_length(client
, false, errp
);
755 ret
= nbd_negotiate_handle_list(client
, errp
);
760 /* NBD spec says we must try to reply before
761 * disconnecting, but that we must also tolerate
762 * guests that don't wait for our reply. */
763 nbd_negotiate_send_rep(client
, NBD_REP_ACK
, NULL
);
766 case NBD_OPT_EXPORT_NAME
:
767 return nbd_negotiate_handle_export_name(client
,
773 ret
= nbd_negotiate_handle_info(client
, myflags
, errp
);
775 assert(option
== NBD_OPT_GO
);
780 case NBD_OPT_STARTTLS
:
782 ret
= nbd_reject_length(client
, false, errp
);
783 } else if (client
->tlscreds
) {
784 ret
= nbd_negotiate_send_rep_err(client
,
785 NBD_REP_ERR_INVALID
, errp
,
786 "TLS already enabled");
788 ret
= nbd_negotiate_send_rep_err(client
,
789 NBD_REP_ERR_POLICY
, errp
,
790 "TLS not configured");
794 case NBD_OPT_STRUCTURED_REPLY
:
796 ret
= nbd_reject_length(client
, false, errp
);
797 } else if (client
->structured_reply
) {
798 ret
= nbd_negotiate_send_rep_err(
799 client
, NBD_REP_ERR_INVALID
, errp
,
800 "structured reply already negotiated");
802 ret
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
803 client
->structured_reply
= true;
804 myflags
|= NBD_FLAG_SEND_DF
;
809 ret
= nbd_opt_drop(client
, NBD_REP_ERR_UNSUP
, errp
,
810 "Unsupported option %" PRIu32
" (%s)",
811 option
, nbd_opt_lookup(option
));
816 * If broken new-style we should drop the connection
817 * for anything except NBD_OPT_EXPORT_NAME
820 case NBD_OPT_EXPORT_NAME
:
821 return nbd_negotiate_handle_export_name(client
,
826 error_setg(errp
, "Unsupported option %" PRIu32
" (%s)",
827 option
, nbd_opt_lookup(option
));
839 * -errno on error, errp is set
840 * 0 on successful negotiation, errp is not set
841 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
844 static coroutine_fn
int nbd_negotiate(NBDClient
*client
, Error
**errp
)
846 char buf
[NBD_OLDSTYLE_NEGOTIATE_SIZE
] = "";
848 const uint16_t myflags
= (NBD_FLAG_HAS_FLAGS
| NBD_FLAG_SEND_TRIM
|
849 NBD_FLAG_SEND_FLUSH
| NBD_FLAG_SEND_FUA
|
850 NBD_FLAG_SEND_WRITE_ZEROES
);
853 /* Old style negotiation header, no room for options
854 [ 0 .. 7] passwd ("NBDMAGIC")
855 [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
857 [24 .. 27] export flags (zero-extended)
858 [28 .. 151] reserved (0)
860 New style negotiation header, client can send options
861 [ 0 .. 7] passwd ("NBDMAGIC")
862 [ 8 .. 15] magic (NBD_OPTS_MAGIC)
863 [16 .. 17] server flags (0)
864 ....options sent, ending in NBD_OPT_EXPORT_NAME or NBD_OPT_GO....
867 qio_channel_set_blocking(client
->ioc
, false, NULL
);
869 trace_nbd_negotiate_begin();
870 memcpy(buf
, "NBDMAGIC", 8);
872 oldStyle
= client
->exp
!= NULL
&& !client
->tlscreds
;
874 trace_nbd_negotiate_old_style(client
->exp
->size
,
875 client
->exp
->nbdflags
| myflags
);
876 stq_be_p(buf
+ 8, NBD_CLIENT_MAGIC
);
877 stq_be_p(buf
+ 16, client
->exp
->size
);
878 stl_be_p(buf
+ 24, client
->exp
->nbdflags
| myflags
);
880 if (nbd_write(client
->ioc
, buf
, sizeof(buf
), errp
) < 0) {
881 error_prepend(errp
, "write failed: ");
885 stq_be_p(buf
+ 8, NBD_OPTS_MAGIC
);
886 stw_be_p(buf
+ 16, NBD_FLAG_FIXED_NEWSTYLE
| NBD_FLAG_NO_ZEROES
);
888 if (nbd_write(client
->ioc
, buf
, 18, errp
) < 0) {
889 error_prepend(errp
, "write failed: ");
892 ret
= nbd_negotiate_options(client
, myflags
, errp
);
895 error_prepend(errp
, "option negotiation failed: ");
901 assert(!client
->optlen
);
902 trace_nbd_negotiate_success();
907 static int nbd_receive_request(QIOChannel
*ioc
, NBDRequest
*request
,
910 uint8_t buf
[NBD_REQUEST_SIZE
];
914 ret
= nbd_read(ioc
, buf
, sizeof(buf
), errp
);
920 [ 0 .. 3] magic (NBD_REQUEST_MAGIC)
921 [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...)
922 [ 6 .. 7] type (NBD_CMD_READ, ...)
928 magic
= ldl_be_p(buf
);
929 request
->flags
= lduw_be_p(buf
+ 4);
930 request
->type
= lduw_be_p(buf
+ 6);
931 request
->handle
= ldq_be_p(buf
+ 8);
932 request
->from
= ldq_be_p(buf
+ 16);
933 request
->len
= ldl_be_p(buf
+ 24);
935 trace_nbd_receive_request(magic
, request
->flags
, request
->type
,
936 request
->from
, request
->len
);
938 if (magic
!= NBD_REQUEST_MAGIC
) {
939 error_setg(errp
, "invalid magic (got 0x%" PRIx32
")", magic
);
945 #define MAX_NBD_REQUESTS 16
947 void nbd_client_get(NBDClient
*client
)
952 void nbd_client_put(NBDClient
*client
)
954 if (--client
->refcount
== 0) {
955 /* The last reference should be dropped by client->close,
956 * which is called by client_close.
958 assert(client
->closing
);
960 qio_channel_detach_aio_context(client
->ioc
);
961 object_unref(OBJECT(client
->sioc
));
962 object_unref(OBJECT(client
->ioc
));
963 if (client
->tlscreds
) {
964 object_unref(OBJECT(client
->tlscreds
));
966 g_free(client
->tlsaclname
);
968 QTAILQ_REMOVE(&client
->exp
->clients
, client
, next
);
969 nbd_export_put(client
->exp
);
975 static void client_close(NBDClient
*client
, bool negotiated
)
977 if (client
->closing
) {
981 client
->closing
= true;
983 /* Force requests to finish. They will drop their own references,
984 * then we'll close the socket and free the NBDClient.
986 qio_channel_shutdown(client
->ioc
, QIO_CHANNEL_SHUTDOWN_BOTH
,
989 /* Also tell the client, so that they release their reference. */
990 if (client
->close_fn
) {
991 client
->close_fn(client
, negotiated
);
995 static NBDRequestData
*nbd_request_get(NBDClient
*client
)
999 assert(client
->nb_requests
<= MAX_NBD_REQUESTS
- 1);
1000 client
->nb_requests
++;
1002 req
= g_new0(NBDRequestData
, 1);
1003 nbd_client_get(client
);
1004 req
->client
= client
;
1008 static void nbd_request_put(NBDRequestData
*req
)
1010 NBDClient
*client
= req
->client
;
1013 qemu_vfree(req
->data
);
1017 client
->nb_requests
--;
1018 nbd_client_receive_next_request(client
);
1020 nbd_client_put(client
);
1023 static void blk_aio_attached(AioContext
*ctx
, void *opaque
)
1025 NBDExport
*exp
= opaque
;
1028 trace_nbd_blk_aio_attached(exp
->name
, ctx
);
1032 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1033 qio_channel_attach_aio_context(client
->ioc
, ctx
);
1034 if (client
->recv_coroutine
) {
1035 aio_co_schedule(ctx
, client
->recv_coroutine
);
1037 if (client
->send_coroutine
) {
1038 aio_co_schedule(ctx
, client
->send_coroutine
);
1043 static void blk_aio_detach(void *opaque
)
1045 NBDExport
*exp
= opaque
;
1048 trace_nbd_blk_aio_detach(exp
->name
, exp
->ctx
);
1050 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1051 qio_channel_detach_aio_context(client
->ioc
);
1057 static void nbd_eject_notifier(Notifier
*n
, void *data
)
1059 NBDExport
*exp
= container_of(n
, NBDExport
, eject_notifier
);
1060 nbd_export_close(exp
);
1063 NBDExport
*nbd_export_new(BlockDriverState
*bs
, off_t dev_offset
, off_t size
,
1064 uint16_t nbdflags
, void (*close
)(NBDExport
*),
1065 bool writethrough
, BlockBackend
*on_eject_blk
,
1070 NBDExport
*exp
= g_new0(NBDExport
, 1);
1075 * NBD exports are used for non-shared storage migration. Make sure
1076 * that BDRV_O_INACTIVE is cleared and the image is ready for write
1077 * access since the export could be available before migration handover.
1079 ctx
= bdrv_get_aio_context(bs
);
1080 aio_context_acquire(ctx
);
1081 bdrv_invalidate_cache(bs
, NULL
);
1082 aio_context_release(ctx
);
1084 /* Don't allow resize while the NBD server is running, otherwise we don't
1085 * care what happens with the node. */
1086 perm
= BLK_PERM_CONSISTENT_READ
;
1087 if ((nbdflags
& NBD_FLAG_READ_ONLY
) == 0) {
1088 perm
|= BLK_PERM_WRITE
;
1090 blk
= blk_new(perm
, BLK_PERM_CONSISTENT_READ
| BLK_PERM_WRITE_UNCHANGED
|
1091 BLK_PERM_WRITE
| BLK_PERM_GRAPH_MOD
);
1092 ret
= blk_insert_bs(blk
, bs
, errp
);
1096 blk_set_enable_write_cache(blk
, !writethrough
);
1099 QTAILQ_INIT(&exp
->clients
);
1101 exp
->dev_offset
= dev_offset
;
1102 exp
->nbdflags
= nbdflags
;
1103 exp
->size
= size
< 0 ? blk_getlength(blk
) : size
;
1104 if (exp
->size
< 0) {
1105 error_setg_errno(errp
, -exp
->size
,
1106 "Failed to determine the NBD export's length");
1109 exp
->size
-= exp
->size
% BDRV_SECTOR_SIZE
;
1112 exp
->ctx
= blk_get_aio_context(blk
);
1113 blk_add_aio_context_notifier(blk
, blk_aio_attached
, blk_aio_detach
, exp
);
1116 blk_ref(on_eject_blk
);
1117 exp
->eject_notifier_blk
= on_eject_blk
;
1118 exp
->eject_notifier
.notify
= nbd_eject_notifier
;
1119 blk_add_remove_bs_notifier(on_eject_blk
, &exp
->eject_notifier
);
1129 NBDExport
*nbd_export_find(const char *name
)
1132 QTAILQ_FOREACH(exp
, &exports
, next
) {
1133 if (strcmp(name
, exp
->name
) == 0) {
1141 void nbd_export_set_name(NBDExport
*exp
, const char *name
)
1143 if (exp
->name
== name
) {
1147 nbd_export_get(exp
);
1148 if (exp
->name
!= NULL
) {
1151 QTAILQ_REMOVE(&exports
, exp
, next
);
1152 nbd_export_put(exp
);
1155 nbd_export_get(exp
);
1156 exp
->name
= g_strdup(name
);
1157 QTAILQ_INSERT_TAIL(&exports
, exp
, next
);
1159 nbd_export_put(exp
);
1162 void nbd_export_set_description(NBDExport
*exp
, const char *description
)
1164 g_free(exp
->description
);
1165 exp
->description
= g_strdup(description
);
1168 void nbd_export_close(NBDExport
*exp
)
1170 NBDClient
*client
, *next
;
1172 nbd_export_get(exp
);
1173 QTAILQ_FOREACH_SAFE(client
, &exp
->clients
, next
, next
) {
1174 client_close(client
, true);
1176 nbd_export_set_name(exp
, NULL
);
1177 nbd_export_set_description(exp
, NULL
);
1178 nbd_export_put(exp
);
1181 void nbd_export_remove(NBDExport
*exp
, NbdServerRemoveMode mode
, Error
**errp
)
1183 if (mode
== NBD_SERVER_REMOVE_MODE_HARD
|| QTAILQ_EMPTY(&exp
->clients
)) {
1184 nbd_export_close(exp
);
1188 assert(mode
== NBD_SERVER_REMOVE_MODE_SAFE
);
1190 error_setg(errp
, "export '%s' still in use", exp
->name
);
1191 error_append_hint(errp
, "Use mode='hard' to force client disconnect\n");
1194 void nbd_export_get(NBDExport
*exp
)
1196 assert(exp
->refcount
> 0);
1200 void nbd_export_put(NBDExport
*exp
)
1202 assert(exp
->refcount
> 0);
1203 if (exp
->refcount
== 1) {
1204 nbd_export_close(exp
);
1207 /* nbd_export_close() may theoretically reduce refcount to 0. It may happen
1208 * if someone calls nbd_export_put() on named export not through
1209 * nbd_export_set_name() when refcount is 1. So, let's assert that
1212 assert(exp
->refcount
> 0);
1213 if (--exp
->refcount
== 0) {
1214 assert(exp
->name
== NULL
);
1215 assert(exp
->description
== NULL
);
1222 if (exp
->eject_notifier_blk
) {
1223 notifier_remove(&exp
->eject_notifier
);
1224 blk_unref(exp
->eject_notifier_blk
);
1226 blk_remove_aio_context_notifier(exp
->blk
, blk_aio_attached
,
1227 blk_aio_detach
, exp
);
1228 blk_unref(exp
->blk
);
1236 BlockBackend
*nbd_export_get_blockdev(NBDExport
*exp
)
1241 void nbd_export_close_all(void)
1243 NBDExport
*exp
, *next
;
1245 QTAILQ_FOREACH_SAFE(exp
, &exports
, next
, next
) {
1246 nbd_export_close(exp
);
1250 static int coroutine_fn
nbd_co_send_iov(NBDClient
*client
, struct iovec
*iov
,
1251 unsigned niov
, Error
**errp
)
1255 g_assert(qemu_in_coroutine());
1256 qemu_co_mutex_lock(&client
->send_lock
);
1257 client
->send_coroutine
= qemu_coroutine_self();
1259 ret
= qio_channel_writev_all(client
->ioc
, iov
, niov
, errp
) < 0 ? -EIO
: 0;
1261 client
->send_coroutine
= NULL
;
1262 qemu_co_mutex_unlock(&client
->send_lock
);
1267 static inline void set_be_simple_reply(NBDSimpleReply
*reply
, uint64_t error
,
1270 stl_be_p(&reply
->magic
, NBD_SIMPLE_REPLY_MAGIC
);
1271 stl_be_p(&reply
->error
, error
);
1272 stq_be_p(&reply
->handle
, handle
);
1275 static int nbd_co_send_simple_reply(NBDClient
*client
,
1282 NBDSimpleReply reply
;
1283 int nbd_err
= system_errno_to_nbd_errno(error
);
1284 struct iovec iov
[] = {
1285 {.iov_base
= &reply
, .iov_len
= sizeof(reply
)},
1286 {.iov_base
= data
, .iov_len
= len
}
1289 trace_nbd_co_send_simple_reply(handle
, nbd_err
, nbd_err_lookup(nbd_err
),
1291 set_be_simple_reply(&reply
, nbd_err
, handle
);
1293 return nbd_co_send_iov(client
, iov
, len
? 2 : 1, errp
);
1296 static inline void set_be_chunk(NBDStructuredReplyChunk
*chunk
, uint16_t flags
,
1297 uint16_t type
, uint64_t handle
, uint32_t length
)
1299 stl_be_p(&chunk
->magic
, NBD_STRUCTURED_REPLY_MAGIC
);
1300 stw_be_p(&chunk
->flags
, flags
);
1301 stw_be_p(&chunk
->type
, type
);
1302 stq_be_p(&chunk
->handle
, handle
);
1303 stl_be_p(&chunk
->length
, length
);
1306 static int coroutine_fn
nbd_co_send_structured_done(NBDClient
*client
,
1310 NBDStructuredReplyChunk chunk
;
1311 struct iovec iov
[] = {
1312 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1315 trace_nbd_co_send_structured_done(handle
);
1316 set_be_chunk(&chunk
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_NONE
, handle
, 0);
1318 return nbd_co_send_iov(client
, iov
, 1, errp
);
1321 static int coroutine_fn
nbd_co_send_structured_read(NBDClient
*client
,
1329 NBDStructuredReadData chunk
;
1330 struct iovec iov
[] = {
1331 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1332 {.iov_base
= data
, .iov_len
= size
}
1336 trace_nbd_co_send_structured_read(handle
, offset
, data
, size
);
1337 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1338 NBD_REPLY_TYPE_OFFSET_DATA
, handle
,
1339 sizeof(chunk
) - sizeof(chunk
.h
) + size
);
1340 stq_be_p(&chunk
.offset
, offset
);
1342 return nbd_co_send_iov(client
, iov
, 2, errp
);
1345 static int coroutine_fn
nbd_co_send_sparse_read(NBDClient
*client
,
1353 NBDExport
*exp
= client
->exp
;
1354 size_t progress
= 0;
1356 while (progress
< size
) {
1358 int status
= bdrv_block_status_above(blk_bs(exp
->blk
), NULL
,
1360 size
- progress
, &pnum
, NULL
,
1365 error_setg_errno(errp
, -status
, "unable to check for holes");
1368 assert(pnum
&& pnum
<= size
- progress
);
1369 final
= progress
+ pnum
== size
;
1370 if (status
& BDRV_BLOCK_ZERO
) {
1371 NBDStructuredReadHole chunk
;
1372 struct iovec iov
[] = {
1373 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1376 trace_nbd_co_send_structured_read_hole(handle
, offset
+ progress
,
1378 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1379 NBD_REPLY_TYPE_OFFSET_HOLE
,
1380 handle
, sizeof(chunk
) - sizeof(chunk
.h
));
1381 stq_be_p(&chunk
.offset
, offset
+ progress
);
1382 stl_be_p(&chunk
.length
, pnum
);
1383 ret
= nbd_co_send_iov(client
, iov
, 1, errp
);
1385 ret
= blk_pread(exp
->blk
, offset
+ progress
+ exp
->dev_offset
,
1386 data
+ progress
, pnum
);
1388 error_setg_errno(errp
, -ret
, "reading from file failed");
1391 ret
= nbd_co_send_structured_read(client
, handle
, offset
+ progress
,
1392 data
+ progress
, pnum
, final
,
1404 static int coroutine_fn
nbd_co_send_structured_error(NBDClient
*client
,
1410 NBDStructuredError chunk
;
1411 int nbd_err
= system_errno_to_nbd_errno(error
);
1412 struct iovec iov
[] = {
1413 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1414 {.iov_base
= (char *)msg
, .iov_len
= msg
? strlen(msg
) : 0},
1418 trace_nbd_co_send_structured_error(handle
, nbd_err
,
1419 nbd_err_lookup(nbd_err
), msg
? msg
: "");
1420 set_be_chunk(&chunk
.h
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_ERROR
, handle
,
1421 sizeof(chunk
) - sizeof(chunk
.h
) + iov
[1].iov_len
);
1422 stl_be_p(&chunk
.error
, nbd_err
);
1423 stw_be_p(&chunk
.message_length
, iov
[1].iov_len
);
1425 return nbd_co_send_iov(client
, iov
, 1 + !!iov
[1].iov_len
, errp
);
1428 /* nbd_co_receive_request
1429 * Collect a client request. Return 0 if request looks valid, -EIO to drop
1430 * connection right away, and any other negative value to report an error to
1431 * the client (although the caller may still need to disconnect after reporting
1434 static int nbd_co_receive_request(NBDRequestData
*req
, NBDRequest
*request
,
1437 NBDClient
*client
= req
->client
;
1440 g_assert(qemu_in_coroutine());
1441 assert(client
->recv_coroutine
== qemu_coroutine_self());
1442 if (nbd_receive_request(client
->ioc
, request
, errp
) < 0) {
1446 trace_nbd_co_receive_request_decode_type(request
->handle
, request
->type
,
1447 nbd_cmd_lookup(request
->type
));
1449 if (request
->type
!= NBD_CMD_WRITE
) {
1450 /* No payload, we are ready to read the next request. */
1451 req
->complete
= true;
1454 if (request
->type
== NBD_CMD_DISC
) {
1455 /* Special case: we're going to disconnect without a reply,
1456 * whether or not flags, from, or len are bogus */
1460 if (request
->type
== NBD_CMD_READ
|| request
->type
== NBD_CMD_WRITE
) {
1461 if (request
->len
> NBD_MAX_BUFFER_SIZE
) {
1462 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
1463 request
->len
, NBD_MAX_BUFFER_SIZE
);
1467 req
->data
= blk_try_blockalign(client
->exp
->blk
, request
->len
);
1468 if (req
->data
== NULL
) {
1469 error_setg(errp
, "No memory");
1473 if (request
->type
== NBD_CMD_WRITE
) {
1474 if (nbd_read(client
->ioc
, req
->data
, request
->len
, errp
) < 0) {
1475 error_prepend(errp
, "reading from socket failed: ");
1478 req
->complete
= true;
1480 trace_nbd_co_receive_request_payload_received(request
->handle
,
1484 /* Sanity checks. */
1485 if (client
->exp
->nbdflags
& NBD_FLAG_READ_ONLY
&&
1486 (request
->type
== NBD_CMD_WRITE
||
1487 request
->type
== NBD_CMD_WRITE_ZEROES
||
1488 request
->type
== NBD_CMD_TRIM
)) {
1489 error_setg(errp
, "Export is read-only");
1492 if (request
->from
> client
->exp
->size
||
1493 request
->from
+ request
->len
> client
->exp
->size
) {
1494 error_setg(errp
, "operation past EOF; From: %" PRIu64
", Len: %" PRIu32
1495 ", Size: %" PRIu64
, request
->from
, request
->len
,
1496 (uint64_t)client
->exp
->size
);
1497 return (request
->type
== NBD_CMD_WRITE
||
1498 request
->type
== NBD_CMD_WRITE_ZEROES
) ? -ENOSPC
: -EINVAL
;
1500 valid_flags
= NBD_CMD_FLAG_FUA
;
1501 if (request
->type
== NBD_CMD_READ
&& client
->structured_reply
) {
1502 valid_flags
|= NBD_CMD_FLAG_DF
;
1503 } else if (request
->type
== NBD_CMD_WRITE_ZEROES
) {
1504 valid_flags
|= NBD_CMD_FLAG_NO_HOLE
;
1506 if (request
->flags
& ~valid_flags
) {
1507 error_setg(errp
, "unsupported flags for command %s (got 0x%x)",
1508 nbd_cmd_lookup(request
->type
), request
->flags
);
1515 /* Owns a reference to the NBDClient passed as opaque. */
1516 static coroutine_fn
void nbd_trip(void *opaque
)
1518 NBDClient
*client
= opaque
;
1519 NBDExport
*exp
= client
->exp
;
1520 NBDRequestData
*req
;
1521 NBDRequest request
= { 0 }; /* GCC thinks it can be used uninitialized */
1524 int reply_data_len
= 0;
1525 Error
*local_err
= NULL
;
1529 if (client
->closing
) {
1530 nbd_client_put(client
);
1534 req
= nbd_request_get(client
);
1535 ret
= nbd_co_receive_request(req
, &request
, &local_err
);
1536 client
->recv_coroutine
= NULL
;
1537 nbd_client_receive_next_request(client
);
1546 if (client
->closing
) {
1548 * The client may be closed when we are blocked in
1549 * nbd_co_receive_request()
1554 switch (request
.type
) {
1556 /* XXX: NBD Protocol only documents use of FUA with WRITE */
1557 if (request
.flags
& NBD_CMD_FLAG_FUA
) {
1558 ret
= blk_co_flush(exp
->blk
);
1560 error_setg_errno(&local_err
, -ret
, "flush failed");
1565 if (client
->structured_reply
&& !(request
.flags
& NBD_CMD_FLAG_DF
) &&
1567 ret
= nbd_co_send_sparse_read(req
->client
, request
.handle
,
1568 request
.from
, req
->data
, request
.len
,
1576 ret
= blk_pread(exp
->blk
, request
.from
+ exp
->dev_offset
,
1577 req
->data
, request
.len
);
1579 error_setg_errno(&local_err
, -ret
, "reading from file failed");
1583 reply_data_len
= request
.len
;
1588 if (request
.flags
& NBD_CMD_FLAG_FUA
) {
1589 flags
|= BDRV_REQ_FUA
;
1591 ret
= blk_pwrite(exp
->blk
, request
.from
+ exp
->dev_offset
,
1592 req
->data
, request
.len
, flags
);
1594 error_setg_errno(&local_err
, -ret
, "writing to file failed");
1598 case NBD_CMD_WRITE_ZEROES
:
1600 if (request
.flags
& NBD_CMD_FLAG_FUA
) {
1601 flags
|= BDRV_REQ_FUA
;
1603 if (!(request
.flags
& NBD_CMD_FLAG_NO_HOLE
)) {
1604 flags
|= BDRV_REQ_MAY_UNMAP
;
1606 ret
= blk_pwrite_zeroes(exp
->blk
, request
.from
+ exp
->dev_offset
,
1607 request
.len
, flags
);
1609 error_setg_errno(&local_err
, -ret
, "writing to file failed");
1614 /* unreachable, thanks to special case in nbd_co_receive_request() */
1618 ret
= blk_co_flush(exp
->blk
);
1620 error_setg_errno(&local_err
, -ret
, "flush failed");
1625 ret
= blk_co_pdiscard(exp
->blk
, request
.from
+ exp
->dev_offset
,
1628 error_setg_errno(&local_err
, -ret
, "discard failed");
1633 error_setg(&local_err
, "invalid request type (%" PRIu32
") received",
1640 /* If we get here, local_err was not a fatal error, and should be sent
1643 msg
= g_strdup(error_get_pretty(local_err
));
1644 error_report_err(local_err
);
1648 if (client
->structured_reply
&&
1649 (ret
< 0 || request
.type
== NBD_CMD_READ
)) {
1651 ret
= nbd_co_send_structured_error(req
->client
, request
.handle
,
1652 -ret
, msg
, &local_err
);
1653 } else if (reply_data_len
) {
1654 ret
= nbd_co_send_structured_read(req
->client
, request
.handle
,
1655 request
.from
, req
->data
,
1656 reply_data_len
, true,
1659 ret
= nbd_co_send_structured_done(req
->client
, request
.handle
,
1663 ret
= nbd_co_send_simple_reply(req
->client
, request
.handle
,
1665 req
->data
, reply_data_len
, &local_err
);
1669 error_prepend(&local_err
, "Failed to send reply: ");
1673 /* We must disconnect after NBD_CMD_WRITE if we did not
1676 if (!req
->complete
) {
1677 error_setg(&local_err
, "Request handling failed in intermediate state");
1682 nbd_request_put(req
);
1683 nbd_client_put(client
);
1688 error_reportf_err(local_err
, "Disconnect client, due to: ");
1690 nbd_request_put(req
);
1691 client_close(client
, true);
1692 nbd_client_put(client
);
1695 static void nbd_client_receive_next_request(NBDClient
*client
)
1697 if (!client
->recv_coroutine
&& client
->nb_requests
< MAX_NBD_REQUESTS
) {
1698 nbd_client_get(client
);
1699 client
->recv_coroutine
= qemu_coroutine_create(nbd_trip
, client
);
1700 aio_co_schedule(client
->exp
->ctx
, client
->recv_coroutine
);
1704 static coroutine_fn
void nbd_co_client_start(void *opaque
)
1706 NBDClient
*client
= opaque
;
1707 NBDExport
*exp
= client
->exp
;
1708 Error
*local_err
= NULL
;
1711 nbd_export_get(exp
);
1712 QTAILQ_INSERT_TAIL(&exp
->clients
, client
, next
);
1714 qemu_co_mutex_init(&client
->send_lock
);
1716 if (nbd_negotiate(client
, &local_err
)) {
1718 error_report_err(local_err
);
1720 client_close(client
, false);
1724 nbd_client_receive_next_request(client
);
1728 * Create a new client listener on the given export @exp, using the
1729 * given channel @sioc. Begin servicing it in a coroutine. When the
1730 * connection closes, call @close_fn with an indication of whether the
1731 * client completed negotiation.
1733 void nbd_client_new(NBDExport
*exp
,
1734 QIOChannelSocket
*sioc
,
1735 QCryptoTLSCreds
*tlscreds
,
1736 const char *tlsaclname
,
1737 void (*close_fn
)(NBDClient
*, bool))
1742 client
= g_new0(NBDClient
, 1);
1743 client
->refcount
= 1;
1745 client
->tlscreds
= tlscreds
;
1747 object_ref(OBJECT(client
->tlscreds
));
1749 client
->tlsaclname
= g_strdup(tlsaclname
);
1750 client
->sioc
= sioc
;
1751 object_ref(OBJECT(client
->sioc
));
1752 client
->ioc
= QIO_CHANNEL(sioc
);
1753 object_ref(OBJECT(client
->ioc
));
1754 client
->close_fn
= close_fn
;
1756 co
= qemu_coroutine_create(nbd_co_client_start
, client
);
1757 qemu_coroutine_enter(co
);