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"
22 #include "qemu/queue.h"
24 #include "nbd-internal.h"
25 #include "qemu/units.h"
27 #define NBD_META_ID_BASE_ALLOCATION 0
28 #define NBD_META_ID_DIRTY_BITMAP 1
31 * NBD_MAX_BLOCK_STATUS_EXTENTS: 1 MiB of extents data. An empirical
32 * constant. If an increase is needed, note that the NBD protocol
33 * recommends no larger than 32 mb, so that the client won't consider
34 * the reply as a denial of service attack.
36 #define NBD_MAX_BLOCK_STATUS_EXTENTS (1 * MiB / 8)
38 static int system_errno_to_nbd_errno(int err
)
66 /* Definitions for opaque data types */
68 typedef struct NBDRequestData NBDRequestData
;
70 struct NBDRequestData
{
71 QSIMPLEQ_ENTRY(NBDRequestData
) entry
;
79 void (*close
)(NBDExport
*exp
);
87 QTAILQ_HEAD(, NBDClient
) clients
;
88 QTAILQ_ENTRY(NBDExport
) next
;
92 BlockBackend
*eject_notifier_blk
;
93 Notifier eject_notifier
;
95 BdrvDirtyBitmap
*export_bitmap
;
96 char *export_bitmap_context
;
99 static QTAILQ_HEAD(, NBDExport
) exports
= QTAILQ_HEAD_INITIALIZER(exports
);
101 /* NBDExportMetaContexts represents a list of contexts to be exported,
102 * as selected by NBD_OPT_SET_META_CONTEXT. Also used for
103 * NBD_OPT_LIST_META_CONTEXT. */
104 typedef struct NBDExportMetaContexts
{
106 bool valid
; /* means that negotiation of the option finished without
108 bool base_allocation
; /* export base:allocation context (block status) */
109 bool bitmap
; /* export qemu:dirty-bitmap:<export bitmap name> */
110 } NBDExportMetaContexts
;
114 void (*close_fn
)(NBDClient
*client
, bool negotiated
);
117 QCryptoTLSCreds
*tlscreds
;
119 QIOChannelSocket
*sioc
; /* The underlying data channel */
120 QIOChannel
*ioc
; /* The current I/O channel which may differ (eg TLS) */
122 Coroutine
*recv_coroutine
;
125 Coroutine
*send_coroutine
;
127 QTAILQ_ENTRY(NBDClient
) next
;
131 uint32_t check_align
; /* If non-zero, check for aligned client requests */
133 bool structured_reply
;
134 NBDExportMetaContexts export_meta
;
136 uint32_t opt
; /* Current option being negotiated */
137 uint32_t optlen
; /* remaining length of data in ioc for the option being
141 static void nbd_client_receive_next_request(NBDClient
*client
);
143 /* Basic flow for negotiation
170 static inline void set_be_option_rep(NBDOptionReply
*rep
, uint32_t option
,
171 uint32_t type
, uint32_t length
)
173 stq_be_p(&rep
->magic
, NBD_REP_MAGIC
);
174 stl_be_p(&rep
->option
, option
);
175 stl_be_p(&rep
->type
, type
);
176 stl_be_p(&rep
->length
, length
);
179 /* Send a reply header, including length, but no payload.
180 * Return -errno on error, 0 on success. */
181 static int nbd_negotiate_send_rep_len(NBDClient
*client
, uint32_t type
,
182 uint32_t len
, Error
**errp
)
186 trace_nbd_negotiate_send_rep_len(client
->opt
, nbd_opt_lookup(client
->opt
),
187 type
, nbd_rep_lookup(type
), len
);
189 assert(len
< NBD_MAX_BUFFER_SIZE
);
191 set_be_option_rep(&rep
, client
->opt
, type
, len
);
192 return nbd_write(client
->ioc
, &rep
, sizeof(rep
), errp
);
195 /* Send a reply header with default 0 length.
196 * Return -errno on error, 0 on success. */
197 static int nbd_negotiate_send_rep(NBDClient
*client
, uint32_t type
,
200 return nbd_negotiate_send_rep_len(client
, type
, 0, errp
);
203 /* Send an error reply.
204 * Return -errno on error, 0 on success. */
205 static int GCC_FMT_ATTR(4, 0)
206 nbd_negotiate_send_rep_verr(NBDClient
*client
, uint32_t type
,
207 Error
**errp
, const char *fmt
, va_list va
)
213 msg
= g_strdup_vprintf(fmt
, va
);
216 trace_nbd_negotiate_send_rep_err(msg
);
217 ret
= nbd_negotiate_send_rep_len(client
, type
, len
, errp
);
221 if (nbd_write(client
->ioc
, msg
, len
, errp
) < 0) {
222 error_prepend(errp
, "write failed (error message): ");
233 /* Send an error reply.
234 * Return -errno on error, 0 on success. */
235 static int GCC_FMT_ATTR(4, 5)
236 nbd_negotiate_send_rep_err(NBDClient
*client
, uint32_t type
,
237 Error
**errp
, const char *fmt
, ...)
243 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
248 /* Drop remainder of the current option, and send a reply with the
249 * given error type and message. Return -errno on read or write
250 * failure; or 0 if connection is still live. */
251 static int GCC_FMT_ATTR(4, 0)
252 nbd_opt_vdrop(NBDClient
*client
, uint32_t type
, Error
**errp
,
253 const char *fmt
, va_list va
)
255 int ret
= nbd_drop(client
->ioc
, client
->optlen
, errp
);
259 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
264 static int GCC_FMT_ATTR(4, 5)
265 nbd_opt_drop(NBDClient
*client
, uint32_t type
, Error
**errp
,
266 const char *fmt
, ...)
272 ret
= nbd_opt_vdrop(client
, type
, errp
, fmt
, va
);
278 static int GCC_FMT_ATTR(3, 4)
279 nbd_opt_invalid(NBDClient
*client
, Error
**errp
, const char *fmt
, ...)
285 ret
= nbd_opt_vdrop(client
, NBD_REP_ERR_INVALID
, errp
, fmt
, va
);
291 /* Read size bytes from the unparsed payload of the current option.
292 * Return -errno on I/O error, 0 if option was completely handled by
293 * sending a reply about inconsistent lengths, or 1 on success. */
294 static int nbd_opt_read(NBDClient
*client
, void *buffer
, size_t size
,
297 if (size
> client
->optlen
) {
298 return nbd_opt_invalid(client
, errp
,
299 "Inconsistent lengths in option %s",
300 nbd_opt_lookup(client
->opt
));
302 client
->optlen
-= size
;
303 return qio_channel_read_all(client
->ioc
, buffer
, size
, errp
) < 0 ? -EIO
: 1;
306 /* Drop size bytes from the unparsed payload of the current option.
307 * Return -errno on I/O error, 0 if option was completely handled by
308 * sending a reply about inconsistent lengths, or 1 on success. */
309 static int nbd_opt_skip(NBDClient
*client
, size_t size
, Error
**errp
)
311 if (size
> client
->optlen
) {
312 return nbd_opt_invalid(client
, errp
,
313 "Inconsistent lengths in option %s",
314 nbd_opt_lookup(client
->opt
));
316 client
->optlen
-= size
;
317 return nbd_drop(client
->ioc
, size
, errp
) < 0 ? -EIO
: 1;
322 * Read a string with the format:
323 * uint32_t len (<= NBD_MAX_NAME_SIZE)
324 * len bytes string (not 0-terminated)
326 * @name should be enough to store NBD_MAX_NAME_SIZE+1.
327 * If @length is non-null, it will be set to the actual string length.
329 * Return -errno on I/O error, 0 if option was completely handled by
330 * sending a reply about inconsistent lengths, or 1 on success.
332 static int nbd_opt_read_name(NBDClient
*client
, char *name
, uint32_t *length
,
338 ret
= nbd_opt_read(client
, &len
, sizeof(len
), errp
);
342 len
= cpu_to_be32(len
);
344 if (len
> NBD_MAX_NAME_SIZE
) {
345 return nbd_opt_invalid(client
, errp
,
346 "Invalid name length: %" PRIu32
, len
);
349 ret
= nbd_opt_read(client
, name
, len
, errp
);
362 /* Send a single NBD_REP_SERVER reply to NBD_OPT_LIST, including payload.
363 * Return -errno on error, 0 on success. */
364 static int nbd_negotiate_send_rep_list(NBDClient
*client
, NBDExport
*exp
,
367 size_t name_len
, desc_len
;
369 const char *name
= exp
->name
? exp
->name
: "";
370 const char *desc
= exp
->description
? exp
->description
: "";
371 QIOChannel
*ioc
= client
->ioc
;
374 trace_nbd_negotiate_send_rep_list(name
, desc
);
375 name_len
= strlen(name
);
376 desc_len
= strlen(desc
);
377 len
= name_len
+ desc_len
+ sizeof(len
);
378 ret
= nbd_negotiate_send_rep_len(client
, NBD_REP_SERVER
, len
, errp
);
383 len
= cpu_to_be32(name_len
);
384 if (nbd_write(ioc
, &len
, sizeof(len
), errp
) < 0) {
385 error_prepend(errp
, "write failed (name length): ");
389 if (nbd_write(ioc
, name
, name_len
, errp
) < 0) {
390 error_prepend(errp
, "write failed (name buffer): ");
394 if (nbd_write(ioc
, desc
, desc_len
, errp
) < 0) {
395 error_prepend(errp
, "write failed (description buffer): ");
402 /* Process the NBD_OPT_LIST command, with a potential series of replies.
403 * Return -errno on error, 0 on success. */
404 static int nbd_negotiate_handle_list(NBDClient
*client
, Error
**errp
)
407 assert(client
->opt
== NBD_OPT_LIST
);
409 /* For each export, send a NBD_REP_SERVER reply. */
410 QTAILQ_FOREACH(exp
, &exports
, next
) {
411 if (nbd_negotiate_send_rep_list(client
, exp
, errp
)) {
415 /* Finish with a NBD_REP_ACK. */
416 return nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
419 static void nbd_check_meta_export(NBDClient
*client
)
421 client
->export_meta
.valid
&= client
->exp
== client
->export_meta
.exp
;
424 /* Send a reply to NBD_OPT_EXPORT_NAME.
425 * Return -errno on error, 0 on success. */
426 static int nbd_negotiate_handle_export_name(NBDClient
*client
,
427 uint16_t myflags
, bool no_zeroes
,
430 char name
[NBD_MAX_NAME_SIZE
+ 1];
431 char buf
[NBD_REPLY_EXPORT_NAME_SIZE
] = "";
436 [20 .. xx] export name (length bytes)
439 [ 8 .. 9] export flags
440 [10 .. 133] reserved (0) [unless no_zeroes]
442 trace_nbd_negotiate_handle_export_name();
443 if (client
->optlen
>= sizeof(name
)) {
444 error_setg(errp
, "Bad length received");
447 if (nbd_read(client
->ioc
, name
, client
->optlen
, "export name", errp
) < 0) {
450 name
[client
->optlen
] = '\0';
453 trace_nbd_negotiate_handle_export_name_request(name
);
455 client
->exp
= nbd_export_find(name
);
457 error_setg(errp
, "export not found");
461 trace_nbd_negotiate_new_style_size_flags(client
->exp
->size
,
462 client
->exp
->nbdflags
| myflags
);
463 stq_be_p(buf
, client
->exp
->size
);
464 stw_be_p(buf
+ 8, client
->exp
->nbdflags
| myflags
);
465 len
= no_zeroes
? 10 : sizeof(buf
);
466 ret
= nbd_write(client
->ioc
, buf
, len
, errp
);
468 error_prepend(errp
, "write failed: ");
472 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
473 nbd_export_get(client
->exp
);
474 nbd_check_meta_export(client
);
479 /* Send a single NBD_REP_INFO, with a buffer @buf of @length bytes.
480 * The buffer does NOT include the info type prefix.
481 * Return -errno on error, 0 if ready to send more. */
482 static int nbd_negotiate_send_info(NBDClient
*client
,
483 uint16_t info
, uint32_t length
, void *buf
,
488 trace_nbd_negotiate_send_info(info
, nbd_info_lookup(info
), length
);
489 rc
= nbd_negotiate_send_rep_len(client
, NBD_REP_INFO
,
490 sizeof(info
) + length
, errp
);
494 info
= cpu_to_be16(info
);
495 if (nbd_write(client
->ioc
, &info
, sizeof(info
), errp
) < 0) {
498 if (nbd_write(client
->ioc
, buf
, length
, errp
) < 0) {
504 /* nbd_reject_length: Handle any unexpected payload.
505 * @fatal requests that we quit talking to the client, even if we are able
506 * to successfully send an error reply.
508 * -errno transmission error occurred or @fatal was requested, errp is set
509 * 0 error message successfully sent to client, errp is not set
511 static int nbd_reject_length(NBDClient
*client
, bool fatal
, Error
**errp
)
515 assert(client
->optlen
);
516 ret
= nbd_opt_invalid(client
, errp
, "option '%s' has unexpected length",
517 nbd_opt_lookup(client
->opt
));
519 error_setg(errp
, "option '%s' has unexpected length",
520 nbd_opt_lookup(client
->opt
));
526 /* Handle NBD_OPT_INFO and NBD_OPT_GO.
527 * Return -errno on error, 0 if ready for next option, and 1 to move
528 * into transmission phase. */
529 static int nbd_negotiate_handle_info(NBDClient
*client
, uint16_t myflags
,
533 char name
[NBD_MAX_NAME_SIZE
+ 1];
538 bool sendname
= false;
539 bool blocksize
= false;
541 char buf
[sizeof(uint64_t) + sizeof(uint16_t)];
542 uint32_t check_align
= 0;
545 4 bytes: L, name length (can be 0)
547 2 bytes: N, number of requests (can be 0)
548 N * 2 bytes: N requests
550 rc
= nbd_opt_read_name(client
, name
, &namelen
, errp
);
554 trace_nbd_negotiate_handle_export_name_request(name
);
556 rc
= nbd_opt_read(client
, &requests
, sizeof(requests
), errp
);
560 requests
= be16_to_cpu(requests
);
561 trace_nbd_negotiate_handle_info_requests(requests
);
563 rc
= nbd_opt_read(client
, &request
, sizeof(request
), errp
);
567 request
= be16_to_cpu(request
);
568 trace_nbd_negotiate_handle_info_request(request
,
569 nbd_info_lookup(request
));
570 /* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE;
571 * everything else is either a request we don't know or
572 * something we send regardless of request */
577 case NBD_INFO_BLOCK_SIZE
:
582 if (client
->optlen
) {
583 return nbd_reject_length(client
, false, errp
);
586 exp
= nbd_export_find(name
);
588 return nbd_negotiate_send_rep_err(client
, NBD_REP_ERR_UNKNOWN
,
589 errp
, "export '%s' not present",
593 /* Don't bother sending NBD_INFO_NAME unless client requested it */
595 rc
= nbd_negotiate_send_info(client
, NBD_INFO_NAME
, namelen
, name
,
602 /* Send NBD_INFO_DESCRIPTION only if available, regardless of
604 if (exp
->description
) {
605 size_t len
= strlen(exp
->description
);
607 rc
= nbd_negotiate_send_info(client
, NBD_INFO_DESCRIPTION
,
608 len
, exp
->description
, errp
);
614 /* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
615 * according to whether the client requested it, and according to
616 * whether this is OPT_INFO or OPT_GO. */
617 /* minimum - 1 for back-compat, or actual if client will obey it. */
618 if (client
->opt
== NBD_OPT_INFO
|| blocksize
) {
619 check_align
= sizes
[0] = blk_get_request_alignment(exp
->blk
);
623 assert(sizes
[0] <= NBD_MAX_BUFFER_SIZE
);
624 /* preferred - Hard-code to 4096 for now.
625 * TODO: is blk_bs(blk)->bl.opt_transfer appropriate? */
626 sizes
[1] = MAX(4096, sizes
[0]);
627 /* maximum - At most 32M, but smaller as appropriate. */
628 sizes
[2] = MIN(blk_get_max_transfer(exp
->blk
), NBD_MAX_BUFFER_SIZE
);
629 trace_nbd_negotiate_handle_info_block_size(sizes
[0], sizes
[1], sizes
[2]);
630 sizes
[0] = cpu_to_be32(sizes
[0]);
631 sizes
[1] = cpu_to_be32(sizes
[1]);
632 sizes
[2] = cpu_to_be32(sizes
[2]);
633 rc
= nbd_negotiate_send_info(client
, NBD_INFO_BLOCK_SIZE
,
634 sizeof(sizes
), sizes
, errp
);
639 /* Send NBD_INFO_EXPORT always */
640 trace_nbd_negotiate_new_style_size_flags(exp
->size
,
641 exp
->nbdflags
| myflags
);
642 stq_be_p(buf
, exp
->size
);
643 stw_be_p(buf
+ 8, exp
->nbdflags
| myflags
);
644 rc
= nbd_negotiate_send_info(client
, NBD_INFO_EXPORT
,
645 sizeof(buf
), buf
, errp
);
651 * If the client is just asking for NBD_OPT_INFO, but forgot to
652 * request block sizes in a situation that would impact
653 * performance, then return an error. But for NBD_OPT_GO, we
654 * tolerate all clients, regardless of alignments.
656 if (client
->opt
== NBD_OPT_INFO
&& !blocksize
&&
657 blk_get_request_alignment(exp
->blk
) > 1) {
658 return nbd_negotiate_send_rep_err(client
,
659 NBD_REP_ERR_BLOCK_SIZE_REQD
,
661 "request NBD_INFO_BLOCK_SIZE to "
666 rc
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
671 if (client
->opt
== NBD_OPT_GO
) {
673 client
->check_align
= check_align
;
674 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
675 nbd_export_get(client
->exp
);
676 nbd_check_meta_export(client
);
683 /* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the
684 * new channel for all further (now-encrypted) communication. */
685 static QIOChannel
*nbd_negotiate_handle_starttls(NBDClient
*client
,
690 struct NBDTLSHandshakeData data
= { 0 };
692 assert(client
->opt
== NBD_OPT_STARTTLS
);
694 trace_nbd_negotiate_handle_starttls();
697 if (nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
) < 0) {
701 tioc
= qio_channel_tls_new_server(ioc
,
709 qio_channel_set_name(QIO_CHANNEL(tioc
), "nbd-server-tls");
710 trace_nbd_negotiate_handle_starttls_handshake();
711 data
.loop
= g_main_loop_new(g_main_context_default(), FALSE
);
712 qio_channel_tls_handshake(tioc
,
718 if (!data
.complete
) {
719 g_main_loop_run(data
.loop
);
721 g_main_loop_unref(data
.loop
);
723 object_unref(OBJECT(tioc
));
724 error_propagate(errp
, data
.error
);
728 return QIO_CHANNEL(tioc
);
731 /* nbd_negotiate_send_meta_context
733 * Send one chunk of reply to NBD_OPT_{LIST,SET}_META_CONTEXT
735 * For NBD_OPT_LIST_META_CONTEXT @context_id is ignored, 0 is used instead.
737 static int nbd_negotiate_send_meta_context(NBDClient
*client
,
742 NBDOptionReplyMetaContext opt
;
743 struct iovec iov
[] = {
744 {.iov_base
= &opt
, .iov_len
= sizeof(opt
)},
745 {.iov_base
= (void *)context
, .iov_len
= strlen(context
)}
748 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
752 trace_nbd_negotiate_meta_query_reply(context
, context_id
);
753 set_be_option_rep(&opt
.h
, client
->opt
, NBD_REP_META_CONTEXT
,
754 sizeof(opt
) - sizeof(opt
.h
) + iov
[1].iov_len
);
755 stl_be_p(&opt
.context_id
, context_id
);
757 return qio_channel_writev_all(client
->ioc
, iov
, 2, errp
) < 0 ? -EIO
: 0;
760 /* Read strlen(@pattern) bytes, and set @match to true if they match @pattern.
761 * @match is never set to false.
763 * Return -errno on I/O error, 0 if option was completely handled by
764 * sending a reply about inconsistent lengths, or 1 on success.
766 * Note: return code = 1 doesn't mean that we've read exactly @pattern.
767 * It only means that there are no errors.
769 static int nbd_meta_pattern(NBDClient
*client
, const char *pattern
, bool *match
,
774 size_t len
= strlen(pattern
);
778 query
= g_malloc(len
);
779 ret
= nbd_opt_read(client
, query
, len
, errp
);
785 if (strncmp(query
, pattern
, len
) == 0) {
786 trace_nbd_negotiate_meta_query_parse(pattern
);
789 trace_nbd_negotiate_meta_query_skip("pattern not matched");
797 * Read @len bytes, and set @match to true if they match @pattern, or if @len
798 * is 0 and the client is performing _LIST_. @match is never set to false.
800 * Return -errno on I/O error, 0 if option was completely handled by
801 * sending a reply about inconsistent lengths, or 1 on success.
803 * Note: return code = 1 doesn't mean that we've read exactly @pattern.
804 * It only means that there are no errors.
806 static int nbd_meta_empty_or_pattern(NBDClient
*client
, const char *pattern
,
807 uint32_t len
, bool *match
, Error
**errp
)
810 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
813 trace_nbd_negotiate_meta_query_parse("empty");
817 if (len
!= strlen(pattern
)) {
818 trace_nbd_negotiate_meta_query_skip("different lengths");
819 return nbd_opt_skip(client
, len
, errp
);
822 return nbd_meta_pattern(client
, pattern
, match
, errp
);
825 /* nbd_meta_base_query
827 * Handle queries to 'base' namespace. For now, only the base:allocation
828 * context is available. 'len' is the amount of text remaining to be read from
829 * the current name, after the 'base:' portion has been stripped.
831 * Return -errno on I/O error, 0 if option was completely handled by
832 * sending a reply about inconsistent lengths, or 1 on success.
834 static int nbd_meta_base_query(NBDClient
*client
, NBDExportMetaContexts
*meta
,
835 uint32_t len
, Error
**errp
)
837 return nbd_meta_empty_or_pattern(client
, "allocation", len
,
838 &meta
->base_allocation
, errp
);
841 /* nbd_meta_bitmap_query
843 * Handle query to 'qemu:' namespace.
844 * @len is the amount of text remaining to be read from the current name, after
845 * the 'qemu:' portion has been stripped.
847 * Return -errno on I/O error, 0 if option was completely handled by
848 * sending a reply about inconsistent lengths, or 1 on success. */
849 static int nbd_meta_qemu_query(NBDClient
*client
, NBDExportMetaContexts
*meta
,
850 uint32_t len
, Error
**errp
)
852 bool dirty_bitmap
= false;
853 size_t dirty_bitmap_len
= strlen("dirty-bitmap:");
856 if (!meta
->exp
->export_bitmap
) {
857 trace_nbd_negotiate_meta_query_skip("no dirty-bitmap exported");
858 return nbd_opt_skip(client
, len
, errp
);
862 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
865 trace_nbd_negotiate_meta_query_parse("empty");
869 if (len
< dirty_bitmap_len
) {
870 trace_nbd_negotiate_meta_query_skip("not dirty-bitmap:");
871 return nbd_opt_skip(client
, len
, errp
);
874 len
-= dirty_bitmap_len
;
875 ret
= nbd_meta_pattern(client
, "dirty-bitmap:", &dirty_bitmap
, errp
);
880 trace_nbd_negotiate_meta_query_skip("not dirty-bitmap:");
881 return nbd_opt_skip(client
, len
, errp
);
884 trace_nbd_negotiate_meta_query_parse("dirty-bitmap:");
886 return nbd_meta_empty_or_pattern(
887 client
, meta
->exp
->export_bitmap_context
+
888 strlen("qemu:dirty_bitmap:"), len
, &meta
->bitmap
, errp
);
891 /* nbd_negotiate_meta_query
893 * Parse namespace name and call corresponding function to parse body of the
896 * The only supported namespace now is 'base'.
898 * The function aims not wasting time and memory to read long unknown namespace
901 * Return -errno on I/O error, 0 if option was completely handled by
902 * sending a reply about inconsistent lengths, or 1 on success. */
903 static int nbd_negotiate_meta_query(NBDClient
*client
,
904 NBDExportMetaContexts
*meta
, Error
**errp
)
907 * Both 'qemu' and 'base' namespaces have length = 5 including a
908 * colon. If another length namespace is later introduced, this
909 * should certainly be refactored.
916 ret
= nbd_opt_read(client
, &len
, sizeof(len
), errp
);
920 len
= cpu_to_be32(len
);
923 trace_nbd_negotiate_meta_query_skip("length too short");
924 return nbd_opt_skip(client
, len
, errp
);
928 ret
= nbd_opt_read(client
, ns
, ns_len
, errp
);
933 if (!strncmp(ns
, "base:", ns_len
)) {
934 trace_nbd_negotiate_meta_query_parse("base:");
935 return nbd_meta_base_query(client
, meta
, len
, errp
);
936 } else if (!strncmp(ns
, "qemu:", ns_len
)) {
937 trace_nbd_negotiate_meta_query_parse("qemu:");
938 return nbd_meta_qemu_query(client
, meta
, len
, errp
);
941 trace_nbd_negotiate_meta_query_skip("unknown namespace");
942 return nbd_opt_skip(client
, len
, errp
);
945 /* nbd_negotiate_meta_queries
946 * Handle NBD_OPT_LIST_META_CONTEXT and NBD_OPT_SET_META_CONTEXT
948 * Return -errno on I/O error, or 0 if option was completely handled. */
949 static int nbd_negotiate_meta_queries(NBDClient
*client
,
950 NBDExportMetaContexts
*meta
, Error
**errp
)
953 char export_name
[NBD_MAX_NAME_SIZE
+ 1];
954 NBDExportMetaContexts local_meta
;
958 if (!client
->structured_reply
) {
959 return nbd_opt_invalid(client
, errp
,
960 "request option '%s' when structured reply "
962 nbd_opt_lookup(client
->opt
));
965 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
966 /* Only change the caller's meta on SET. */
970 memset(meta
, 0, sizeof(*meta
));
972 ret
= nbd_opt_read_name(client
, export_name
, NULL
, errp
);
977 meta
->exp
= nbd_export_find(export_name
);
978 if (meta
->exp
== NULL
) {
979 return nbd_opt_drop(client
, NBD_REP_ERR_UNKNOWN
, errp
,
980 "export '%s' not present", export_name
);
983 ret
= nbd_opt_read(client
, &nb_queries
, sizeof(nb_queries
), errp
);
987 nb_queries
= cpu_to_be32(nb_queries
);
988 trace_nbd_negotiate_meta_context(nbd_opt_lookup(client
->opt
),
989 export_name
, nb_queries
);
991 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
&& !nb_queries
) {
992 /* enable all known contexts */
993 meta
->base_allocation
= true;
994 meta
->bitmap
= !!meta
->exp
->export_bitmap
;
996 for (i
= 0; i
< nb_queries
; ++i
) {
997 ret
= nbd_negotiate_meta_query(client
, meta
, errp
);
1004 if (meta
->base_allocation
) {
1005 ret
= nbd_negotiate_send_meta_context(client
, "base:allocation",
1006 NBD_META_ID_BASE_ALLOCATION
,
1014 ret
= nbd_negotiate_send_meta_context(client
,
1015 meta
->exp
->export_bitmap_context
,
1016 NBD_META_ID_DIRTY_BITMAP
,
1023 ret
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
1031 /* nbd_negotiate_options
1032 * Process all NBD_OPT_* client option commands, during fixed newstyle
1035 * -errno on error, errp is set
1036 * 0 on successful negotiation, errp is not set
1037 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
1040 static int nbd_negotiate_options(NBDClient
*client
, uint16_t myflags
,
1044 bool fixedNewstyle
= false;
1045 bool no_zeroes
= false;
1048 [ 0 .. 3] client flags
1050 Then we loop until NBD_OPT_EXPORT_NAME or NBD_OPT_GO:
1051 [ 0 .. 7] NBD_OPTS_MAGIC
1052 [ 8 .. 11] NBD option
1053 [12 .. 15] Data length
1056 [ 0 .. 7] NBD_OPTS_MAGIC
1057 [ 8 .. 11] Second NBD option
1058 [12 .. 15] Data length
1062 if (nbd_read32(client
->ioc
, &flags
, "flags", errp
) < 0) {
1065 trace_nbd_negotiate_options_flags(flags
);
1066 if (flags
& NBD_FLAG_C_FIXED_NEWSTYLE
) {
1067 fixedNewstyle
= true;
1068 flags
&= ~NBD_FLAG_C_FIXED_NEWSTYLE
;
1070 if (flags
& NBD_FLAG_C_NO_ZEROES
) {
1072 flags
&= ~NBD_FLAG_C_NO_ZEROES
;
1075 error_setg(errp
, "Unknown client flags 0x%" PRIx32
" received", flags
);
1081 uint32_t option
, length
;
1084 if (nbd_read64(client
->ioc
, &magic
, "opts magic", errp
) < 0) {
1087 trace_nbd_negotiate_options_check_magic(magic
);
1088 if (magic
!= NBD_OPTS_MAGIC
) {
1089 error_setg(errp
, "Bad magic received");
1093 if (nbd_read32(client
->ioc
, &option
, "option", errp
) < 0) {
1096 client
->opt
= option
;
1098 if (nbd_read32(client
->ioc
, &length
, "option length", errp
) < 0) {
1101 assert(!client
->optlen
);
1102 client
->optlen
= length
;
1104 if (length
> NBD_MAX_BUFFER_SIZE
) {
1105 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
1106 length
, NBD_MAX_BUFFER_SIZE
);
1110 trace_nbd_negotiate_options_check_option(option
,
1111 nbd_opt_lookup(option
));
1112 if (client
->tlscreds
&&
1113 client
->ioc
== (QIOChannel
*)client
->sioc
) {
1115 if (!fixedNewstyle
) {
1116 error_setg(errp
, "Unsupported option 0x%" PRIx32
, option
);
1120 case NBD_OPT_STARTTLS
:
1122 /* Unconditionally drop the connection if the client
1123 * can't start a TLS negotiation correctly */
1124 return nbd_reject_length(client
, true, errp
);
1126 tioc
= nbd_negotiate_handle_starttls(client
, errp
);
1131 object_unref(OBJECT(client
->ioc
));
1132 client
->ioc
= QIO_CHANNEL(tioc
);
1135 case NBD_OPT_EXPORT_NAME
:
1136 /* No way to return an error to client, so drop connection */
1137 error_setg(errp
, "Option 0x%x not permitted before TLS",
1142 /* Let the client keep trying, unless they asked to
1143 * quit. Always try to give an error back to the
1144 * client; but when replying to OPT_ABORT, be aware
1145 * that the client may hang up before receiving the
1146 * error, in which case we are fine ignoring the
1147 * resulting EPIPE. */
1148 ret
= nbd_opt_drop(client
, NBD_REP_ERR_TLS_REQD
,
1149 option
== NBD_OPT_ABORT
? NULL
: errp
,
1151 " not permitted before TLS", option
);
1152 if (option
== NBD_OPT_ABORT
) {
1157 } else if (fixedNewstyle
) {
1161 ret
= nbd_reject_length(client
, false, errp
);
1163 ret
= nbd_negotiate_handle_list(client
, errp
);
1168 /* NBD spec says we must try to reply before
1169 * disconnecting, but that we must also tolerate
1170 * guests that don't wait for our reply. */
1171 nbd_negotiate_send_rep(client
, NBD_REP_ACK
, NULL
);
1174 case NBD_OPT_EXPORT_NAME
:
1175 return nbd_negotiate_handle_export_name(client
,
1181 ret
= nbd_negotiate_handle_info(client
, myflags
, errp
);
1183 assert(option
== NBD_OPT_GO
);
1188 case NBD_OPT_STARTTLS
:
1190 ret
= nbd_reject_length(client
, false, errp
);
1191 } else if (client
->tlscreds
) {
1192 ret
= nbd_negotiate_send_rep_err(client
,
1193 NBD_REP_ERR_INVALID
, errp
,
1194 "TLS already enabled");
1196 ret
= nbd_negotiate_send_rep_err(client
,
1197 NBD_REP_ERR_POLICY
, errp
,
1198 "TLS not configured");
1202 case NBD_OPT_STRUCTURED_REPLY
:
1204 ret
= nbd_reject_length(client
, false, errp
);
1205 } else if (client
->structured_reply
) {
1206 ret
= nbd_negotiate_send_rep_err(
1207 client
, NBD_REP_ERR_INVALID
, errp
,
1208 "structured reply already negotiated");
1210 ret
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
1211 client
->structured_reply
= true;
1212 myflags
|= NBD_FLAG_SEND_DF
;
1216 case NBD_OPT_LIST_META_CONTEXT
:
1217 case NBD_OPT_SET_META_CONTEXT
:
1218 ret
= nbd_negotiate_meta_queries(client
, &client
->export_meta
,
1223 ret
= nbd_opt_drop(client
, NBD_REP_ERR_UNSUP
, errp
,
1224 "Unsupported option %" PRIu32
" (%s)",
1225 option
, nbd_opt_lookup(option
));
1230 * If broken new-style we should drop the connection
1231 * for anything except NBD_OPT_EXPORT_NAME
1234 case NBD_OPT_EXPORT_NAME
:
1235 return nbd_negotiate_handle_export_name(client
,
1240 error_setg(errp
, "Unsupported option %" PRIu32
" (%s)",
1241 option
, nbd_opt_lookup(option
));
1253 * -errno on error, errp is set
1254 * 0 on successful negotiation, errp is not set
1255 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
1258 static coroutine_fn
int nbd_negotiate(NBDClient
*client
, Error
**errp
)
1260 char buf
[NBD_OLDSTYLE_NEGOTIATE_SIZE
] = "";
1262 const uint16_t myflags
= (NBD_FLAG_HAS_FLAGS
| NBD_FLAG_SEND_TRIM
|
1263 NBD_FLAG_SEND_FLUSH
| NBD_FLAG_SEND_FUA
|
1264 NBD_FLAG_SEND_WRITE_ZEROES
| NBD_FLAG_SEND_CACHE
);
1266 /* Old style negotiation header, no room for options
1267 [ 0 .. 7] passwd ("NBDMAGIC")
1268 [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
1270 [24 .. 27] export flags (zero-extended)
1271 [28 .. 151] reserved (0)
1273 New style negotiation header, client can send options
1274 [ 0 .. 7] passwd ("NBDMAGIC")
1275 [ 8 .. 15] magic (NBD_OPTS_MAGIC)
1276 [16 .. 17] server flags (0)
1277 ....options sent, ending in NBD_OPT_EXPORT_NAME or NBD_OPT_GO....
1280 qio_channel_set_blocking(client
->ioc
, false, NULL
);
1282 trace_nbd_negotiate_begin();
1283 memcpy(buf
, "NBDMAGIC", 8);
1285 stq_be_p(buf
+ 8, NBD_OPTS_MAGIC
);
1286 stw_be_p(buf
+ 16, NBD_FLAG_FIXED_NEWSTYLE
| NBD_FLAG_NO_ZEROES
);
1288 if (nbd_write(client
->ioc
, buf
, 18, errp
) < 0) {
1289 error_prepend(errp
, "write failed: ");
1292 ret
= nbd_negotiate_options(client
, myflags
, errp
);
1295 error_prepend(errp
, "option negotiation failed: ");
1300 assert(!client
->optlen
);
1301 trace_nbd_negotiate_success();
1306 static int nbd_receive_request(QIOChannel
*ioc
, NBDRequest
*request
,
1309 uint8_t buf
[NBD_REQUEST_SIZE
];
1313 ret
= nbd_read(ioc
, buf
, sizeof(buf
), "request", errp
);
1319 [ 0 .. 3] magic (NBD_REQUEST_MAGIC)
1320 [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...)
1321 [ 6 .. 7] type (NBD_CMD_READ, ...)
1327 magic
= ldl_be_p(buf
);
1328 request
->flags
= lduw_be_p(buf
+ 4);
1329 request
->type
= lduw_be_p(buf
+ 6);
1330 request
->handle
= ldq_be_p(buf
+ 8);
1331 request
->from
= ldq_be_p(buf
+ 16);
1332 request
->len
= ldl_be_p(buf
+ 24);
1334 trace_nbd_receive_request(magic
, request
->flags
, request
->type
,
1335 request
->from
, request
->len
);
1337 if (magic
!= NBD_REQUEST_MAGIC
) {
1338 error_setg(errp
, "invalid magic (got 0x%" PRIx32
")", magic
);
1344 #define MAX_NBD_REQUESTS 16
1346 void nbd_client_get(NBDClient
*client
)
1351 void nbd_client_put(NBDClient
*client
)
1353 if (--client
->refcount
== 0) {
1354 /* The last reference should be dropped by client->close,
1355 * which is called by client_close.
1357 assert(client
->closing
);
1359 qio_channel_detach_aio_context(client
->ioc
);
1360 object_unref(OBJECT(client
->sioc
));
1361 object_unref(OBJECT(client
->ioc
));
1362 if (client
->tlscreds
) {
1363 object_unref(OBJECT(client
->tlscreds
));
1365 g_free(client
->tlsauthz
);
1367 QTAILQ_REMOVE(&client
->exp
->clients
, client
, next
);
1368 nbd_export_put(client
->exp
);
1374 static void client_close(NBDClient
*client
, bool negotiated
)
1376 if (client
->closing
) {
1380 client
->closing
= true;
1382 /* Force requests to finish. They will drop their own references,
1383 * then we'll close the socket and free the NBDClient.
1385 qio_channel_shutdown(client
->ioc
, QIO_CHANNEL_SHUTDOWN_BOTH
,
1388 /* Also tell the client, so that they release their reference. */
1389 if (client
->close_fn
) {
1390 client
->close_fn(client
, negotiated
);
1394 static NBDRequestData
*nbd_request_get(NBDClient
*client
)
1396 NBDRequestData
*req
;
1398 assert(client
->nb_requests
<= MAX_NBD_REQUESTS
- 1);
1399 client
->nb_requests
++;
1401 req
= g_new0(NBDRequestData
, 1);
1402 nbd_client_get(client
);
1403 req
->client
= client
;
1407 static void nbd_request_put(NBDRequestData
*req
)
1409 NBDClient
*client
= req
->client
;
1412 qemu_vfree(req
->data
);
1416 client
->nb_requests
--;
1417 nbd_client_receive_next_request(client
);
1419 nbd_client_put(client
);
1422 static void blk_aio_attached(AioContext
*ctx
, void *opaque
)
1424 NBDExport
*exp
= opaque
;
1427 trace_nbd_blk_aio_attached(exp
->name
, ctx
);
1431 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1432 qio_channel_attach_aio_context(client
->ioc
, ctx
);
1433 if (client
->recv_coroutine
) {
1434 aio_co_schedule(ctx
, client
->recv_coroutine
);
1436 if (client
->send_coroutine
) {
1437 aio_co_schedule(ctx
, client
->send_coroutine
);
1442 static void blk_aio_detach(void *opaque
)
1444 NBDExport
*exp
= opaque
;
1447 trace_nbd_blk_aio_detach(exp
->name
, exp
->ctx
);
1449 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1450 qio_channel_detach_aio_context(client
->ioc
);
1456 static void nbd_eject_notifier(Notifier
*n
, void *data
)
1458 NBDExport
*exp
= container_of(n
, NBDExport
, eject_notifier
);
1459 nbd_export_close(exp
);
1462 NBDExport
*nbd_export_new(BlockDriverState
*bs
, uint64_t dev_offset
,
1463 uint64_t size
, const char *name
, const char *desc
,
1464 const char *bitmap
, uint16_t nbdflags
,
1465 void (*close
)(NBDExport
*), bool writethrough
,
1466 BlockBackend
*on_eject_blk
, Error
**errp
)
1470 NBDExport
*exp
= g_new0(NBDExport
, 1);
1475 * NBD exports are used for non-shared storage migration. Make sure
1476 * that BDRV_O_INACTIVE is cleared and the image is ready for write
1477 * access since the export could be available before migration handover.
1480 ctx
= bdrv_get_aio_context(bs
);
1481 aio_context_acquire(ctx
);
1482 bdrv_invalidate_cache(bs
, NULL
);
1483 aio_context_release(ctx
);
1485 /* Don't allow resize while the NBD server is running, otherwise we don't
1486 * care what happens with the node. */
1487 perm
= BLK_PERM_CONSISTENT_READ
;
1488 if ((nbdflags
& NBD_FLAG_READ_ONLY
) == 0) {
1489 perm
|= BLK_PERM_WRITE
;
1491 blk
= blk_new(bdrv_get_aio_context(bs
), perm
,
1492 BLK_PERM_CONSISTENT_READ
| BLK_PERM_WRITE_UNCHANGED
|
1493 BLK_PERM_WRITE
| BLK_PERM_GRAPH_MOD
);
1494 ret
= blk_insert_bs(blk
, bs
, errp
);
1498 blk_set_enable_write_cache(blk
, !writethrough
);
1499 blk_set_allow_aio_context_change(blk
, true);
1502 QTAILQ_INIT(&exp
->clients
);
1504 assert(dev_offset
<= INT64_MAX
);
1505 exp
->dev_offset
= dev_offset
;
1506 exp
->name
= g_strdup(name
);
1507 exp
->description
= g_strdup(desc
);
1508 exp
->nbdflags
= nbdflags
;
1509 assert(size
<= INT64_MAX
- dev_offset
);
1510 exp
->size
= QEMU_ALIGN_DOWN(size
, BDRV_SECTOR_SIZE
);
1513 BdrvDirtyBitmap
*bm
= NULL
;
1516 bm
= bdrv_find_dirty_bitmap(bs
, bitmap
);
1517 if (bm
!= NULL
|| bs
->backing
== NULL
) {
1521 bs
= bs
->backing
->bs
;
1525 error_setg(errp
, "Bitmap '%s' is not found", bitmap
);
1529 if (bdrv_dirty_bitmap_check(bm
, BDRV_BITMAP_ALLOW_RO
, errp
)) {
1533 if ((nbdflags
& NBD_FLAG_READ_ONLY
) && bdrv_is_writable(bs
) &&
1534 bdrv_dirty_bitmap_enabled(bm
)) {
1536 "Enabled bitmap '%s' incompatible with readonly export",
1541 bdrv_dirty_bitmap_set_busy(bm
, true);
1542 exp
->export_bitmap
= bm
;
1543 exp
->export_bitmap_context
= g_strdup_printf("qemu:dirty-bitmap:%s",
1548 exp
->ctx
= blk_get_aio_context(blk
);
1549 blk_add_aio_context_notifier(blk
, blk_aio_attached
, blk_aio_detach
, exp
);
1552 blk_ref(on_eject_blk
);
1553 exp
->eject_notifier_blk
= on_eject_blk
;
1554 exp
->eject_notifier
.notify
= nbd_eject_notifier
;
1555 blk_add_remove_bs_notifier(on_eject_blk
, &exp
->eject_notifier
);
1557 QTAILQ_INSERT_TAIL(&exports
, exp
, next
);
1558 nbd_export_get(exp
);
1564 g_free(exp
->description
);
1569 NBDExport
*nbd_export_find(const char *name
)
1572 QTAILQ_FOREACH(exp
, &exports
, next
) {
1573 if (strcmp(name
, exp
->name
) == 0) {
1581 void nbd_export_close(NBDExport
*exp
)
1583 NBDClient
*client
, *next
;
1585 nbd_export_get(exp
);
1587 * TODO: Should we expand QMP NbdServerRemoveNode enum to allow a
1588 * close mode that stops advertising the export to new clients but
1589 * still permits existing clients to run to completion? Because of
1590 * that possibility, nbd_export_close() can be called more than
1591 * once on an export.
1593 QTAILQ_FOREACH_SAFE(client
, &exp
->clients
, next
, next
) {
1594 client_close(client
, true);
1597 nbd_export_put(exp
);
1600 QTAILQ_REMOVE(&exports
, exp
, next
);
1602 g_free(exp
->description
);
1603 exp
->description
= NULL
;
1604 nbd_export_put(exp
);
1607 void nbd_export_remove(NBDExport
*exp
, NbdServerRemoveMode mode
, Error
**errp
)
1609 if (mode
== NBD_SERVER_REMOVE_MODE_HARD
|| QTAILQ_EMPTY(&exp
->clients
)) {
1610 nbd_export_close(exp
);
1614 assert(mode
== NBD_SERVER_REMOVE_MODE_SAFE
);
1616 error_setg(errp
, "export '%s' still in use", exp
->name
);
1617 error_append_hint(errp
, "Use mode='hard' to force client disconnect\n");
1620 void nbd_export_get(NBDExport
*exp
)
1622 assert(exp
->refcount
> 0);
1626 void nbd_export_put(NBDExport
*exp
)
1628 assert(exp
->refcount
> 0);
1629 if (exp
->refcount
== 1) {
1630 nbd_export_close(exp
);
1633 /* nbd_export_close() may theoretically reduce refcount to 0. It may happen
1634 * if someone calls nbd_export_put() on named export not through
1635 * nbd_export_set_name() when refcount is 1. So, let's assert that
1638 assert(exp
->refcount
> 0);
1639 if (--exp
->refcount
== 0) {
1640 assert(exp
->name
== NULL
);
1641 assert(exp
->description
== NULL
);
1648 if (exp
->eject_notifier_blk
) {
1649 notifier_remove(&exp
->eject_notifier
);
1650 blk_unref(exp
->eject_notifier_blk
);
1652 blk_remove_aio_context_notifier(exp
->blk
, blk_aio_attached
,
1653 blk_aio_detach
, exp
);
1654 blk_unref(exp
->blk
);
1658 if (exp
->export_bitmap
) {
1659 bdrv_dirty_bitmap_set_busy(exp
->export_bitmap
, false);
1660 g_free(exp
->export_bitmap_context
);
1667 BlockBackend
*nbd_export_get_blockdev(NBDExport
*exp
)
1672 void nbd_export_close_all(void)
1674 NBDExport
*exp
, *next
;
1676 QTAILQ_FOREACH_SAFE(exp
, &exports
, next
, next
) {
1677 nbd_export_close(exp
);
1681 static int coroutine_fn
nbd_co_send_iov(NBDClient
*client
, struct iovec
*iov
,
1682 unsigned niov
, Error
**errp
)
1686 g_assert(qemu_in_coroutine());
1687 qemu_co_mutex_lock(&client
->send_lock
);
1688 client
->send_coroutine
= qemu_coroutine_self();
1690 ret
= qio_channel_writev_all(client
->ioc
, iov
, niov
, errp
) < 0 ? -EIO
: 0;
1692 client
->send_coroutine
= NULL
;
1693 qemu_co_mutex_unlock(&client
->send_lock
);
1698 static inline void set_be_simple_reply(NBDSimpleReply
*reply
, uint64_t error
,
1701 stl_be_p(&reply
->magic
, NBD_SIMPLE_REPLY_MAGIC
);
1702 stl_be_p(&reply
->error
, error
);
1703 stq_be_p(&reply
->handle
, handle
);
1706 static int nbd_co_send_simple_reply(NBDClient
*client
,
1713 NBDSimpleReply reply
;
1714 int nbd_err
= system_errno_to_nbd_errno(error
);
1715 struct iovec iov
[] = {
1716 {.iov_base
= &reply
, .iov_len
= sizeof(reply
)},
1717 {.iov_base
= data
, .iov_len
= len
}
1720 trace_nbd_co_send_simple_reply(handle
, nbd_err
, nbd_err_lookup(nbd_err
),
1722 set_be_simple_reply(&reply
, nbd_err
, handle
);
1724 return nbd_co_send_iov(client
, iov
, len
? 2 : 1, errp
);
1727 static inline void set_be_chunk(NBDStructuredReplyChunk
*chunk
, uint16_t flags
,
1728 uint16_t type
, uint64_t handle
, uint32_t length
)
1730 stl_be_p(&chunk
->magic
, NBD_STRUCTURED_REPLY_MAGIC
);
1731 stw_be_p(&chunk
->flags
, flags
);
1732 stw_be_p(&chunk
->type
, type
);
1733 stq_be_p(&chunk
->handle
, handle
);
1734 stl_be_p(&chunk
->length
, length
);
1737 static int coroutine_fn
nbd_co_send_structured_done(NBDClient
*client
,
1741 NBDStructuredReplyChunk chunk
;
1742 struct iovec iov
[] = {
1743 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1746 trace_nbd_co_send_structured_done(handle
);
1747 set_be_chunk(&chunk
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_NONE
, handle
, 0);
1749 return nbd_co_send_iov(client
, iov
, 1, errp
);
1752 static int coroutine_fn
nbd_co_send_structured_read(NBDClient
*client
,
1760 NBDStructuredReadData chunk
;
1761 struct iovec iov
[] = {
1762 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1763 {.iov_base
= data
, .iov_len
= size
}
1767 trace_nbd_co_send_structured_read(handle
, offset
, data
, size
);
1768 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1769 NBD_REPLY_TYPE_OFFSET_DATA
, handle
,
1770 sizeof(chunk
) - sizeof(chunk
.h
) + size
);
1771 stq_be_p(&chunk
.offset
, offset
);
1773 return nbd_co_send_iov(client
, iov
, 2, errp
);
1776 static int coroutine_fn
nbd_co_send_structured_error(NBDClient
*client
,
1782 NBDStructuredError chunk
;
1783 int nbd_err
= system_errno_to_nbd_errno(error
);
1784 struct iovec iov
[] = {
1785 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1786 {.iov_base
= (char *)msg
, .iov_len
= msg
? strlen(msg
) : 0},
1790 trace_nbd_co_send_structured_error(handle
, nbd_err
,
1791 nbd_err_lookup(nbd_err
), msg
? msg
: "");
1792 set_be_chunk(&chunk
.h
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_ERROR
, handle
,
1793 sizeof(chunk
) - sizeof(chunk
.h
) + iov
[1].iov_len
);
1794 stl_be_p(&chunk
.error
, nbd_err
);
1795 stw_be_p(&chunk
.message_length
, iov
[1].iov_len
);
1797 return nbd_co_send_iov(client
, iov
, 1 + !!iov
[1].iov_len
, errp
);
1800 /* Do a sparse read and send the structured reply to the client.
1801 * Returns -errno if sending fails. bdrv_block_status_above() failure is
1802 * reported to the client, at which point this function succeeds.
1804 static int coroutine_fn
nbd_co_send_sparse_read(NBDClient
*client
,
1812 NBDExport
*exp
= client
->exp
;
1813 size_t progress
= 0;
1815 while (progress
< size
) {
1817 int status
= bdrv_block_status_above(blk_bs(exp
->blk
), NULL
,
1819 size
- progress
, &pnum
, NULL
,
1824 char *msg
= g_strdup_printf("unable to check for holes: %s",
1827 ret
= nbd_co_send_structured_error(client
, handle
, -status
, msg
,
1832 assert(pnum
&& pnum
<= size
- progress
);
1833 final
= progress
+ pnum
== size
;
1834 if (status
& BDRV_BLOCK_ZERO
) {
1835 NBDStructuredReadHole chunk
;
1836 struct iovec iov
[] = {
1837 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1840 trace_nbd_co_send_structured_read_hole(handle
, offset
+ progress
,
1842 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1843 NBD_REPLY_TYPE_OFFSET_HOLE
,
1844 handle
, sizeof(chunk
) - sizeof(chunk
.h
));
1845 stq_be_p(&chunk
.offset
, offset
+ progress
);
1846 stl_be_p(&chunk
.length
, pnum
);
1847 ret
= nbd_co_send_iov(client
, iov
, 1, errp
);
1849 ret
= blk_pread(exp
->blk
, offset
+ progress
+ exp
->dev_offset
,
1850 data
+ progress
, pnum
);
1852 error_setg_errno(errp
, -ret
, "reading from file failed");
1855 ret
= nbd_co_send_structured_read(client
, handle
, offset
+ progress
,
1856 data
+ progress
, pnum
, final
,
1869 * Populate @extents from block status. Update @bytes to be the actual
1870 * length encoded (which may be smaller than the original), and update
1871 * @nb_extents to the number of extents used.
1873 * Returns zero on success and -errno on bdrv_block_status_above failure.
1875 static int blockstatus_to_extents(BlockDriverState
*bs
, uint64_t offset
,
1876 uint64_t *bytes
, NBDExtent
*extents
,
1877 unsigned int *nb_extents
)
1879 uint64_t remaining_bytes
= *bytes
;
1880 NBDExtent
*extent
= extents
, *extents_end
= extents
+ *nb_extents
;
1881 bool first_extent
= true;
1883 assert(*nb_extents
);
1884 while (remaining_bytes
) {
1887 int ret
= bdrv_block_status_above(bs
, NULL
, offset
, remaining_bytes
,
1894 flags
= (ret
& BDRV_BLOCK_ALLOCATED
? 0 : NBD_STATE_HOLE
) |
1895 (ret
& BDRV_BLOCK_ZERO
? NBD_STATE_ZERO
: 0);
1898 extent
->flags
= flags
;
1899 extent
->length
= num
;
1900 first_extent
= false;
1901 } else if (flags
== extent
->flags
) {
1902 /* extend current extent */
1903 extent
->length
+= num
;
1905 if (extent
+ 1 == extents_end
) {
1909 /* start new extent */
1911 extent
->flags
= flags
;
1912 extent
->length
= num
;
1915 remaining_bytes
-= num
;
1918 extents_end
= extent
+ 1;
1920 for (extent
= extents
; extent
< extents_end
; extent
++) {
1921 extent
->flags
= cpu_to_be32(extent
->flags
);
1922 extent
->length
= cpu_to_be32(extent
->length
);
1925 *bytes
-= remaining_bytes
;
1926 *nb_extents
= extents_end
- extents
;
1931 /* nbd_co_send_extents
1933 * @length is only for tracing purposes (and may be smaller or larger
1934 * than the client's original request). @last controls whether
1935 * NBD_REPLY_FLAG_DONE is sent. @extents should already be in
1936 * big-endian format.
1938 static int nbd_co_send_extents(NBDClient
*client
, uint64_t handle
,
1939 NBDExtent
*extents
, unsigned int nb_extents
,
1940 uint64_t length
, bool last
,
1941 uint32_t context_id
, Error
**errp
)
1943 NBDStructuredMeta chunk
;
1945 struct iovec iov
[] = {
1946 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1947 {.iov_base
= extents
, .iov_len
= nb_extents
* sizeof(extents
[0])}
1950 trace_nbd_co_send_extents(handle
, nb_extents
, context_id
, length
, last
);
1951 set_be_chunk(&chunk
.h
, last
? NBD_REPLY_FLAG_DONE
: 0,
1952 NBD_REPLY_TYPE_BLOCK_STATUS
,
1953 handle
, sizeof(chunk
) - sizeof(chunk
.h
) + iov
[1].iov_len
);
1954 stl_be_p(&chunk
.context_id
, context_id
);
1956 return nbd_co_send_iov(client
, iov
, 2, errp
);
1959 /* Get block status from the exported device and send it to the client */
1960 static int nbd_co_send_block_status(NBDClient
*client
, uint64_t handle
,
1961 BlockDriverState
*bs
, uint64_t offset
,
1962 uint32_t length
, bool dont_fragment
,
1963 bool last
, uint32_t context_id
,
1967 unsigned int nb_extents
= dont_fragment
? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS
;
1968 NBDExtent
*extents
= g_new(NBDExtent
, nb_extents
);
1969 uint64_t final_length
= length
;
1971 ret
= blockstatus_to_extents(bs
, offset
, &final_length
, extents
,
1975 return nbd_co_send_structured_error(
1976 client
, handle
, -ret
, "can't get block status", errp
);
1979 ret
= nbd_co_send_extents(client
, handle
, extents
, nb_extents
,
1980 final_length
, last
, context_id
, errp
);
1988 * Populate @extents from a dirty bitmap. Unless @dont_fragment, the
1989 * final extent may exceed the original @length. Store in @length the
1990 * byte length encoded (which may be smaller or larger than the
1991 * original), and return the number of extents used.
1993 static unsigned int bitmap_to_extents(BdrvDirtyBitmap
*bitmap
, uint64_t offset
,
1994 uint64_t *length
, NBDExtent
*extents
,
1995 unsigned int nb_extents
,
1998 uint64_t begin
= offset
, end
= offset
;
1999 uint64_t overall_end
= offset
+ *length
;
2001 BdrvDirtyBitmapIter
*it
;
2004 bdrv_dirty_bitmap_lock(bitmap
);
2006 it
= bdrv_dirty_iter_new(bitmap
);
2007 dirty
= bdrv_dirty_bitmap_get_locked(bitmap
, offset
);
2009 assert(begin
< overall_end
&& nb_extents
);
2010 while (begin
< overall_end
&& i
< nb_extents
) {
2011 bool next_dirty
= !dirty
;
2014 end
= bdrv_dirty_bitmap_next_zero(bitmap
, begin
, UINT64_MAX
);
2016 bdrv_set_dirty_iter(it
, begin
);
2017 end
= bdrv_dirty_iter_next(it
);
2019 if (end
== -1 || end
- begin
> UINT32_MAX
) {
2020 /* Cap to an aligned value < 4G beyond begin. */
2021 end
= MIN(bdrv_dirty_bitmap_size(bitmap
),
2022 begin
+ UINT32_MAX
+ 1 -
2023 bdrv_dirty_bitmap_granularity(bitmap
));
2026 if (dont_fragment
&& end
> overall_end
) {
2030 extents
[i
].length
= cpu_to_be32(end
- begin
);
2031 extents
[i
].flags
= cpu_to_be32(dirty
? NBD_STATE_DIRTY
: 0);
2037 bdrv_dirty_iter_free(it
);
2039 bdrv_dirty_bitmap_unlock(bitmap
);
2041 assert(offset
< end
);
2042 *length
= end
- offset
;
2046 static int nbd_co_send_bitmap(NBDClient
*client
, uint64_t handle
,
2047 BdrvDirtyBitmap
*bitmap
, uint64_t offset
,
2048 uint32_t length
, bool dont_fragment
, bool last
,
2049 uint32_t context_id
, Error
**errp
)
2052 unsigned int nb_extents
= dont_fragment
? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS
;
2053 NBDExtent
*extents
= g_new(NBDExtent
, nb_extents
);
2054 uint64_t final_length
= length
;
2056 nb_extents
= bitmap_to_extents(bitmap
, offset
, &final_length
, extents
,
2057 nb_extents
, dont_fragment
);
2059 ret
= nbd_co_send_extents(client
, handle
, extents
, nb_extents
,
2060 final_length
, last
, context_id
, errp
);
2067 /* nbd_co_receive_request
2068 * Collect a client request. Return 0 if request looks valid, -EIO to drop
2069 * connection right away, and any other negative value to report an error to
2070 * the client (although the caller may still need to disconnect after reporting
2073 static int nbd_co_receive_request(NBDRequestData
*req
, NBDRequest
*request
,
2076 NBDClient
*client
= req
->client
;
2079 g_assert(qemu_in_coroutine());
2080 assert(client
->recv_coroutine
== qemu_coroutine_self());
2081 if (nbd_receive_request(client
->ioc
, request
, errp
) < 0) {
2085 trace_nbd_co_receive_request_decode_type(request
->handle
, request
->type
,
2086 nbd_cmd_lookup(request
->type
));
2088 if (request
->type
!= NBD_CMD_WRITE
) {
2089 /* No payload, we are ready to read the next request. */
2090 req
->complete
= true;
2093 if (request
->type
== NBD_CMD_DISC
) {
2094 /* Special case: we're going to disconnect without a reply,
2095 * whether or not flags, from, or len are bogus */
2099 if (request
->type
== NBD_CMD_READ
|| request
->type
== NBD_CMD_WRITE
||
2100 request
->type
== NBD_CMD_CACHE
)
2102 if (request
->len
> NBD_MAX_BUFFER_SIZE
) {
2103 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
2104 request
->len
, NBD_MAX_BUFFER_SIZE
);
2108 if (request
->type
!= NBD_CMD_CACHE
) {
2109 req
->data
= blk_try_blockalign(client
->exp
->blk
, request
->len
);
2110 if (req
->data
== NULL
) {
2111 error_setg(errp
, "No memory");
2117 if (request
->type
== NBD_CMD_WRITE
) {
2118 if (nbd_read(client
->ioc
, req
->data
, request
->len
, "CMD_WRITE data",
2123 req
->complete
= true;
2125 trace_nbd_co_receive_request_payload_received(request
->handle
,
2129 /* Sanity checks. */
2130 if (client
->exp
->nbdflags
& NBD_FLAG_READ_ONLY
&&
2131 (request
->type
== NBD_CMD_WRITE
||
2132 request
->type
== NBD_CMD_WRITE_ZEROES
||
2133 request
->type
== NBD_CMD_TRIM
)) {
2134 error_setg(errp
, "Export is read-only");
2137 if (request
->from
> client
->exp
->size
||
2138 request
->len
> client
->exp
->size
- request
->from
) {
2139 error_setg(errp
, "operation past EOF; From: %" PRIu64
", Len: %" PRIu32
2140 ", Size: %" PRIu64
, request
->from
, request
->len
,
2142 return (request
->type
== NBD_CMD_WRITE
||
2143 request
->type
== NBD_CMD_WRITE_ZEROES
) ? -ENOSPC
: -EINVAL
;
2145 if (client
->check_align
&& !QEMU_IS_ALIGNED(request
->from
| request
->len
,
2146 client
->check_align
)) {
2148 * The block layer gracefully handles unaligned requests, but
2149 * it's still worth tracing client non-compliance
2151 trace_nbd_co_receive_align_compliance(nbd_cmd_lookup(request
->type
),
2154 client
->check_align
);
2156 valid_flags
= NBD_CMD_FLAG_FUA
;
2157 if (request
->type
== NBD_CMD_READ
&& client
->structured_reply
) {
2158 valid_flags
|= NBD_CMD_FLAG_DF
;
2159 } else if (request
->type
== NBD_CMD_WRITE_ZEROES
) {
2160 valid_flags
|= NBD_CMD_FLAG_NO_HOLE
;
2161 } else if (request
->type
== NBD_CMD_BLOCK_STATUS
) {
2162 valid_flags
|= NBD_CMD_FLAG_REQ_ONE
;
2164 if (request
->flags
& ~valid_flags
) {
2165 error_setg(errp
, "unsupported flags for command %s (got 0x%x)",
2166 nbd_cmd_lookup(request
->type
), request
->flags
);
2173 /* Send simple reply without a payload, or a structured error
2174 * @error_msg is ignored if @ret >= 0
2175 * Returns 0 if connection is still live, -errno on failure to talk to client
2177 static coroutine_fn
int nbd_send_generic_reply(NBDClient
*client
,
2180 const char *error_msg
,
2183 if (client
->structured_reply
&& ret
< 0) {
2184 return nbd_co_send_structured_error(client
, handle
, -ret
, error_msg
,
2187 return nbd_co_send_simple_reply(client
, handle
, ret
< 0 ? -ret
: 0,
2192 /* Handle NBD_CMD_READ request.
2193 * Return -errno if sending fails. Other errors are reported directly to the
2194 * client as an error reply. */
2195 static coroutine_fn
int nbd_do_cmd_read(NBDClient
*client
, NBDRequest
*request
,
2196 uint8_t *data
, Error
**errp
)
2199 NBDExport
*exp
= client
->exp
;
2201 assert(request
->type
== NBD_CMD_READ
);
2203 /* XXX: NBD Protocol only documents use of FUA with WRITE */
2204 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2205 ret
= blk_co_flush(exp
->blk
);
2207 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2208 "flush failed", errp
);
2212 if (client
->structured_reply
&& !(request
->flags
& NBD_CMD_FLAG_DF
) &&
2215 return nbd_co_send_sparse_read(client
, request
->handle
, request
->from
,
2216 data
, request
->len
, errp
);
2219 ret
= blk_pread(exp
->blk
, request
->from
+ exp
->dev_offset
, data
,
2222 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2223 "reading from file failed", errp
);
2226 if (client
->structured_reply
) {
2228 return nbd_co_send_structured_read(client
, request
->handle
,
2229 request
->from
, data
,
2230 request
->len
, true, errp
);
2232 return nbd_co_send_structured_done(client
, request
->handle
, errp
);
2235 return nbd_co_send_simple_reply(client
, request
->handle
, 0,
2236 data
, request
->len
, errp
);
2243 * Handle NBD_CMD_CACHE request.
2244 * Return -errno if sending fails. Other errors are reported directly to the
2245 * client as an error reply.
2247 static coroutine_fn
int nbd_do_cmd_cache(NBDClient
*client
, NBDRequest
*request
,
2251 NBDExport
*exp
= client
->exp
;
2253 assert(request
->type
== NBD_CMD_CACHE
);
2255 ret
= blk_co_preadv(exp
->blk
, request
->from
+ exp
->dev_offset
, request
->len
,
2256 NULL
, BDRV_REQ_COPY_ON_READ
| BDRV_REQ_PREFETCH
);
2258 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2259 "caching data failed", errp
);
2262 /* Handle NBD request.
2263 * Return -errno if sending fails. Other errors are reported directly to the
2264 * client as an error reply. */
2265 static coroutine_fn
int nbd_handle_request(NBDClient
*client
,
2266 NBDRequest
*request
,
2267 uint8_t *data
, Error
**errp
)
2271 NBDExport
*exp
= client
->exp
;
2274 switch (request
->type
) {
2276 return nbd_do_cmd_cache(client
, request
, errp
);
2279 return nbd_do_cmd_read(client
, request
, data
, errp
);
2283 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2284 flags
|= BDRV_REQ_FUA
;
2286 ret
= blk_pwrite(exp
->blk
, request
->from
+ exp
->dev_offset
,
2287 data
, request
->len
, flags
);
2288 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2289 "writing to file failed", errp
);
2291 case NBD_CMD_WRITE_ZEROES
:
2293 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2294 flags
|= BDRV_REQ_FUA
;
2296 if (!(request
->flags
& NBD_CMD_FLAG_NO_HOLE
)) {
2297 flags
|= BDRV_REQ_MAY_UNMAP
;
2299 ret
= blk_pwrite_zeroes(exp
->blk
, request
->from
+ exp
->dev_offset
,
2300 request
->len
, flags
);
2301 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2302 "writing to file failed", errp
);
2305 /* unreachable, thanks to special case in nbd_co_receive_request() */
2309 ret
= blk_co_flush(exp
->blk
);
2310 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2311 "flush failed", errp
);
2314 ret
= blk_co_pdiscard(exp
->blk
, request
->from
+ exp
->dev_offset
,
2316 if (ret
== 0 && request
->flags
& NBD_CMD_FLAG_FUA
) {
2317 ret
= blk_co_flush(exp
->blk
);
2319 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2320 "discard failed", errp
);
2322 case NBD_CMD_BLOCK_STATUS
:
2323 if (!request
->len
) {
2324 return nbd_send_generic_reply(client
, request
->handle
, -EINVAL
,
2325 "need non-zero length", errp
);
2327 if (client
->export_meta
.valid
&&
2328 (client
->export_meta
.base_allocation
||
2329 client
->export_meta
.bitmap
))
2331 bool dont_fragment
= request
->flags
& NBD_CMD_FLAG_REQ_ONE
;
2333 if (client
->export_meta
.base_allocation
) {
2334 ret
= nbd_co_send_block_status(client
, request
->handle
,
2335 blk_bs(exp
->blk
), request
->from
,
2336 request
->len
, dont_fragment
,
2337 !client
->export_meta
.bitmap
,
2338 NBD_META_ID_BASE_ALLOCATION
,
2345 if (client
->export_meta
.bitmap
) {
2346 ret
= nbd_co_send_bitmap(client
, request
->handle
,
2347 client
->exp
->export_bitmap
,
2348 request
->from
, request
->len
,
2350 true, NBD_META_ID_DIRTY_BITMAP
, errp
);
2358 return nbd_send_generic_reply(client
, request
->handle
, -EINVAL
,
2359 "CMD_BLOCK_STATUS not negotiated",
2364 msg
= g_strdup_printf("invalid request type (%" PRIu32
") received",
2366 ret
= nbd_send_generic_reply(client
, request
->handle
, -EINVAL
, msg
,
2373 /* Owns a reference to the NBDClient passed as opaque. */
2374 static coroutine_fn
void nbd_trip(void *opaque
)
2376 NBDClient
*client
= opaque
;
2377 NBDRequestData
*req
;
2378 NBDRequest request
= { 0 }; /* GCC thinks it can be used uninitialized */
2380 Error
*local_err
= NULL
;
2383 if (client
->closing
) {
2384 nbd_client_put(client
);
2388 req
= nbd_request_get(client
);
2389 ret
= nbd_co_receive_request(req
, &request
, &local_err
);
2390 client
->recv_coroutine
= NULL
;
2392 if (client
->closing
) {
2394 * The client may be closed when we are blocked in
2395 * nbd_co_receive_request()
2400 nbd_client_receive_next_request(client
);
2406 /* It wans't -EIO, so, according to nbd_co_receive_request()
2407 * semantics, we should return the error to the client. */
2408 Error
*export_err
= local_err
;
2411 ret
= nbd_send_generic_reply(client
, request
.handle
, -EINVAL
,
2412 error_get_pretty(export_err
), &local_err
);
2413 error_free(export_err
);
2415 ret
= nbd_handle_request(client
, &request
, req
->data
, &local_err
);
2418 error_prepend(&local_err
, "Failed to send reply: ");
2422 /* We must disconnect after NBD_CMD_WRITE if we did not
2425 if (!req
->complete
) {
2426 error_setg(&local_err
, "Request handling failed in intermediate state");
2431 nbd_request_put(req
);
2432 nbd_client_put(client
);
2437 error_reportf_err(local_err
, "Disconnect client, due to: ");
2439 nbd_request_put(req
);
2440 client_close(client
, true);
2441 nbd_client_put(client
);
2444 static void nbd_client_receive_next_request(NBDClient
*client
)
2446 if (!client
->recv_coroutine
&& client
->nb_requests
< MAX_NBD_REQUESTS
) {
2447 nbd_client_get(client
);
2448 client
->recv_coroutine
= qemu_coroutine_create(nbd_trip
, client
);
2449 aio_co_schedule(client
->exp
->ctx
, client
->recv_coroutine
);
2453 static coroutine_fn
void nbd_co_client_start(void *opaque
)
2455 NBDClient
*client
= opaque
;
2456 Error
*local_err
= NULL
;
2458 qemu_co_mutex_init(&client
->send_lock
);
2460 if (nbd_negotiate(client
, &local_err
)) {
2462 error_report_err(local_err
);
2464 client_close(client
, false);
2468 nbd_client_receive_next_request(client
);
2472 * Create a new client listener using the given channel @sioc.
2473 * Begin servicing it in a coroutine. When the connection closes, call
2474 * @close_fn with an indication of whether the client completed negotiation.
2476 void nbd_client_new(QIOChannelSocket
*sioc
,
2477 QCryptoTLSCreds
*tlscreds
,
2478 const char *tlsauthz
,
2479 void (*close_fn
)(NBDClient
*, bool))
2484 client
= g_new0(NBDClient
, 1);
2485 client
->refcount
= 1;
2486 client
->tlscreds
= tlscreds
;
2488 object_ref(OBJECT(client
->tlscreds
));
2490 client
->tlsauthz
= g_strdup(tlsauthz
);
2491 client
->sioc
= sioc
;
2492 object_ref(OBJECT(client
->sioc
));
2493 client
->ioc
= QIO_CHANNEL(sioc
);
2494 object_ref(OBJECT(client
->ioc
));
2495 client
->close_fn
= close_fn
;
2497 co
= qemu_coroutine_create(nbd_co_client_start
, client
);
2498 qemu_coroutine_enter(co
);