2 * Copyright (C) 2016-2020 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"
22 #include "block/export.h"
23 #include "qapi/error.h"
24 #include "qemu/queue.h"
26 #include "nbd-internal.h"
27 #include "qemu/units.h"
29 #define NBD_META_ID_BASE_ALLOCATION 0
30 #define NBD_META_ID_DIRTY_BITMAP 1
33 * NBD_MAX_BLOCK_STATUS_EXTENTS: 1 MiB of extents data. An empirical
34 * constant. If an increase is needed, note that the NBD protocol
35 * recommends no larger than 32 mb, so that the client won't consider
36 * the reply as a denial of service attack.
38 #define NBD_MAX_BLOCK_STATUS_EXTENTS (1 * MiB / 8)
40 static int system_errno_to_nbd_errno(int err
)
61 #if ENOTSUP != EOPNOTSUPP
73 /* Definitions for opaque data types */
75 typedef struct NBDRequestData NBDRequestData
;
77 struct NBDRequestData
{
78 QSIMPLEQ_ENTRY(NBDRequestData
) entry
;
91 QTAILQ_HEAD(, NBDClient
) clients
;
92 QTAILQ_ENTRY(NBDExport
) next
;
94 BlockBackend
*eject_notifier_blk
;
95 Notifier eject_notifier
;
97 BdrvDirtyBitmap
*export_bitmap
;
98 char *export_bitmap_context
;
101 static QTAILQ_HEAD(, NBDExport
) exports
= QTAILQ_HEAD_INITIALIZER(exports
);
103 /* NBDExportMetaContexts represents a list of contexts to be exported,
104 * as selected by NBD_OPT_SET_META_CONTEXT. Also used for
105 * NBD_OPT_LIST_META_CONTEXT. */
106 typedef struct NBDExportMetaContexts
{
108 bool valid
; /* means that negotiation of the option finished without
110 bool base_allocation
; /* export base:allocation context (block status) */
111 bool bitmap
; /* export qemu:dirty-bitmap:<export bitmap name> */
112 } NBDExportMetaContexts
;
116 void (*close_fn
)(NBDClient
*client
, bool negotiated
);
119 QCryptoTLSCreds
*tlscreds
;
121 QIOChannelSocket
*sioc
; /* The underlying data channel */
122 QIOChannel
*ioc
; /* The current I/O channel which may differ (eg TLS) */
124 Coroutine
*recv_coroutine
;
127 Coroutine
*send_coroutine
;
129 QTAILQ_ENTRY(NBDClient
) next
;
133 uint32_t check_align
; /* If non-zero, check for aligned client requests */
135 bool structured_reply
;
136 NBDExportMetaContexts export_meta
;
138 uint32_t opt
; /* Current option being negotiated */
139 uint32_t optlen
; /* remaining length of data in ioc for the option being
143 static void nbd_client_receive_next_request(NBDClient
*client
);
145 /* Basic flow for negotiation
172 static inline void set_be_option_rep(NBDOptionReply
*rep
, uint32_t option
,
173 uint32_t type
, uint32_t length
)
175 stq_be_p(&rep
->magic
, NBD_REP_MAGIC
);
176 stl_be_p(&rep
->option
, option
);
177 stl_be_p(&rep
->type
, type
);
178 stl_be_p(&rep
->length
, length
);
181 /* Send a reply header, including length, but no payload.
182 * Return -errno on error, 0 on success. */
183 static int nbd_negotiate_send_rep_len(NBDClient
*client
, uint32_t type
,
184 uint32_t len
, Error
**errp
)
188 trace_nbd_negotiate_send_rep_len(client
->opt
, nbd_opt_lookup(client
->opt
),
189 type
, nbd_rep_lookup(type
), len
);
191 assert(len
< NBD_MAX_BUFFER_SIZE
);
193 set_be_option_rep(&rep
, client
->opt
, type
, len
);
194 return nbd_write(client
->ioc
, &rep
, sizeof(rep
), errp
);
197 /* Send a reply header with default 0 length.
198 * Return -errno on error, 0 on success. */
199 static int nbd_negotiate_send_rep(NBDClient
*client
, uint32_t type
,
202 return nbd_negotiate_send_rep_len(client
, type
, 0, errp
);
205 /* Send an error reply.
206 * Return -errno on error, 0 on success. */
207 static int GCC_FMT_ATTR(4, 0)
208 nbd_negotiate_send_rep_verr(NBDClient
*client
, uint32_t type
,
209 Error
**errp
, const char *fmt
, va_list va
)
212 g_autofree
char *msg
= NULL
;
216 msg
= g_strdup_vprintf(fmt
, va
);
218 assert(len
< NBD_MAX_STRING_SIZE
);
219 trace_nbd_negotiate_send_rep_err(msg
);
220 ret
= nbd_negotiate_send_rep_len(client
, type
, len
, errp
);
224 if (nbd_write(client
->ioc
, msg
, len
, errp
) < 0) {
225 error_prepend(errp
, "write failed (error message): ");
233 * Return a malloc'd copy of @name suitable for use in an error reply.
236 nbd_sanitize_name(const char *name
)
238 if (strnlen(name
, 80) < 80) {
239 return g_strdup(name
);
241 /* XXX Should we also try to sanitize any control characters? */
242 return g_strdup_printf("%.80s...", name
);
245 /* Send an error reply.
246 * Return -errno on error, 0 on success. */
247 static int GCC_FMT_ATTR(4, 5)
248 nbd_negotiate_send_rep_err(NBDClient
*client
, uint32_t type
,
249 Error
**errp
, const char *fmt
, ...)
255 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
260 /* Drop remainder of the current option, and send a reply with the
261 * given error type and message. Return -errno on read or write
262 * failure; or 0 if connection is still live. */
263 static int GCC_FMT_ATTR(4, 0)
264 nbd_opt_vdrop(NBDClient
*client
, uint32_t type
, Error
**errp
,
265 const char *fmt
, va_list va
)
267 int ret
= nbd_drop(client
->ioc
, client
->optlen
, errp
);
271 ret
= nbd_negotiate_send_rep_verr(client
, type
, errp
, fmt
, va
);
276 static int GCC_FMT_ATTR(4, 5)
277 nbd_opt_drop(NBDClient
*client
, uint32_t type
, Error
**errp
,
278 const char *fmt
, ...)
284 ret
= nbd_opt_vdrop(client
, type
, errp
, fmt
, va
);
290 static int GCC_FMT_ATTR(3, 4)
291 nbd_opt_invalid(NBDClient
*client
, Error
**errp
, const char *fmt
, ...)
297 ret
= nbd_opt_vdrop(client
, NBD_REP_ERR_INVALID
, errp
, fmt
, va
);
303 /* Read size bytes from the unparsed payload of the current option.
304 * If @check_nul, require that no NUL bytes appear in buffer.
305 * Return -errno on I/O error, 0 if option was completely handled by
306 * sending a reply about inconsistent lengths, or 1 on success. */
307 static int nbd_opt_read(NBDClient
*client
, void *buffer
, size_t size
,
308 bool check_nul
, Error
**errp
)
310 if (size
> client
->optlen
) {
311 return nbd_opt_invalid(client
, errp
,
312 "Inconsistent lengths in option %s",
313 nbd_opt_lookup(client
->opt
));
315 client
->optlen
-= size
;
316 if (qio_channel_read_all(client
->ioc
, buffer
, size
, errp
) < 0) {
320 if (check_nul
&& strnlen(buffer
, size
) != size
) {
321 return nbd_opt_invalid(client
, errp
,
322 "Unexpected embedded NUL in option %s",
323 nbd_opt_lookup(client
->opt
));
328 /* Drop size bytes from the unparsed payload of the current option.
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. */
331 static int nbd_opt_skip(NBDClient
*client
, size_t size
, Error
**errp
)
333 if (size
> client
->optlen
) {
334 return nbd_opt_invalid(client
, errp
,
335 "Inconsistent lengths in option %s",
336 nbd_opt_lookup(client
->opt
));
338 client
->optlen
-= size
;
339 return nbd_drop(client
->ioc
, size
, errp
) < 0 ? -EIO
: 1;
344 * Read a string with the format:
345 * uint32_t len (<= NBD_MAX_STRING_SIZE)
346 * len bytes string (not 0-terminated)
348 * On success, @name will be allocated.
349 * If @length is non-null, it will be set to the actual string length.
351 * Return -errno on I/O error, 0 if option was completely handled by
352 * sending a reply about inconsistent lengths, or 1 on success.
354 static int nbd_opt_read_name(NBDClient
*client
, char **name
, uint32_t *length
,
359 g_autofree
char *local_name
= NULL
;
362 ret
= nbd_opt_read(client
, &len
, sizeof(len
), false, errp
);
366 len
= cpu_to_be32(len
);
368 if (len
> NBD_MAX_STRING_SIZE
) {
369 return nbd_opt_invalid(client
, errp
,
370 "Invalid name length: %" PRIu32
, len
);
373 local_name
= g_malloc(len
+ 1);
374 ret
= nbd_opt_read(client
, local_name
, len
, true, errp
);
378 local_name
[len
] = '\0';
383 *name
= g_steal_pointer(&local_name
);
388 /* Send a single NBD_REP_SERVER reply to NBD_OPT_LIST, including payload.
389 * Return -errno on error, 0 on success. */
390 static int nbd_negotiate_send_rep_list(NBDClient
*client
, NBDExport
*exp
,
394 size_t name_len
, desc_len
;
396 const char *name
= exp
->name
? exp
->name
: "";
397 const char *desc
= exp
->description
? exp
->description
: "";
398 QIOChannel
*ioc
= client
->ioc
;
401 trace_nbd_negotiate_send_rep_list(name
, desc
);
402 name_len
= strlen(name
);
403 desc_len
= strlen(desc
);
404 assert(name_len
<= NBD_MAX_STRING_SIZE
&& desc_len
<= NBD_MAX_STRING_SIZE
);
405 len
= name_len
+ desc_len
+ sizeof(len
);
406 ret
= nbd_negotiate_send_rep_len(client
, NBD_REP_SERVER
, len
, errp
);
411 len
= cpu_to_be32(name_len
);
412 if (nbd_write(ioc
, &len
, sizeof(len
), errp
) < 0) {
413 error_prepend(errp
, "write failed (name length): ");
417 if (nbd_write(ioc
, name
, name_len
, errp
) < 0) {
418 error_prepend(errp
, "write failed (name buffer): ");
422 if (nbd_write(ioc
, desc
, desc_len
, errp
) < 0) {
423 error_prepend(errp
, "write failed (description buffer): ");
430 /* Process the NBD_OPT_LIST command, with a potential series of replies.
431 * Return -errno on error, 0 on success. */
432 static int nbd_negotiate_handle_list(NBDClient
*client
, Error
**errp
)
435 assert(client
->opt
== NBD_OPT_LIST
);
437 /* For each export, send a NBD_REP_SERVER reply. */
438 QTAILQ_FOREACH(exp
, &exports
, next
) {
439 if (nbd_negotiate_send_rep_list(client
, exp
, errp
)) {
443 /* Finish with a NBD_REP_ACK. */
444 return nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
447 static void nbd_check_meta_export(NBDClient
*client
)
449 client
->export_meta
.valid
&= client
->exp
== client
->export_meta
.exp
;
452 /* Send a reply to NBD_OPT_EXPORT_NAME.
453 * Return -errno on error, 0 on success. */
454 static int nbd_negotiate_handle_export_name(NBDClient
*client
, bool no_zeroes
,
458 g_autofree
char *name
= NULL
;
459 char buf
[NBD_REPLY_EXPORT_NAME_SIZE
] = "";
465 [20 .. xx] export name (length bytes)
468 [ 8 .. 9] export flags
469 [10 .. 133] reserved (0) [unless no_zeroes]
471 trace_nbd_negotiate_handle_export_name();
472 if (client
->optlen
> NBD_MAX_STRING_SIZE
) {
473 error_setg(errp
, "Bad length received");
476 name
= g_malloc(client
->optlen
+ 1);
477 if (nbd_read(client
->ioc
, name
, client
->optlen
, "export name", errp
) < 0) {
480 name
[client
->optlen
] = '\0';
483 trace_nbd_negotiate_handle_export_name_request(name
);
485 client
->exp
= nbd_export_find(name
);
487 error_setg(errp
, "export not found");
491 myflags
= client
->exp
->nbdflags
;
492 if (client
->structured_reply
) {
493 myflags
|= NBD_FLAG_SEND_DF
;
495 trace_nbd_negotiate_new_style_size_flags(client
->exp
->size
, myflags
);
496 stq_be_p(buf
, client
->exp
->size
);
497 stw_be_p(buf
+ 8, myflags
);
498 len
= no_zeroes
? 10 : sizeof(buf
);
499 ret
= nbd_write(client
->ioc
, buf
, len
, errp
);
501 error_prepend(errp
, "write failed: ");
505 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
506 blk_exp_ref(&client
->exp
->common
);
507 nbd_check_meta_export(client
);
512 /* Send a single NBD_REP_INFO, with a buffer @buf of @length bytes.
513 * The buffer does NOT include the info type prefix.
514 * Return -errno on error, 0 if ready to send more. */
515 static int nbd_negotiate_send_info(NBDClient
*client
,
516 uint16_t info
, uint32_t length
, void *buf
,
521 trace_nbd_negotiate_send_info(info
, nbd_info_lookup(info
), length
);
522 rc
= nbd_negotiate_send_rep_len(client
, NBD_REP_INFO
,
523 sizeof(info
) + length
, errp
);
527 info
= cpu_to_be16(info
);
528 if (nbd_write(client
->ioc
, &info
, sizeof(info
), errp
) < 0) {
531 if (nbd_write(client
->ioc
, buf
, length
, errp
) < 0) {
537 /* nbd_reject_length: Handle any unexpected payload.
538 * @fatal requests that we quit talking to the client, even if we are able
539 * to successfully send an error reply.
541 * -errno transmission error occurred or @fatal was requested, errp is set
542 * 0 error message successfully sent to client, errp is not set
544 static int nbd_reject_length(NBDClient
*client
, bool fatal
, Error
**errp
)
548 assert(client
->optlen
);
549 ret
= nbd_opt_invalid(client
, errp
, "option '%s' has unexpected length",
550 nbd_opt_lookup(client
->opt
));
552 error_setg(errp
, "option '%s' has unexpected length",
553 nbd_opt_lookup(client
->opt
));
559 /* Handle NBD_OPT_INFO and NBD_OPT_GO.
560 * Return -errno on error, 0 if ready for next option, and 1 to move
561 * into transmission phase. */
562 static int nbd_negotiate_handle_info(NBDClient
*client
, Error
**errp
)
565 g_autofree
char *name
= NULL
;
569 uint32_t namelen
= 0;
570 bool sendname
= false;
571 bool blocksize
= false;
573 char buf
[sizeof(uint64_t) + sizeof(uint16_t)];
574 uint32_t check_align
= 0;
578 4 bytes: L, name length (can be 0)
580 2 bytes: N, number of requests (can be 0)
581 N * 2 bytes: N requests
583 rc
= nbd_opt_read_name(client
, &name
, &namelen
, errp
);
587 trace_nbd_negotiate_handle_export_name_request(name
);
589 rc
= nbd_opt_read(client
, &requests
, sizeof(requests
), false, errp
);
593 requests
= be16_to_cpu(requests
);
594 trace_nbd_negotiate_handle_info_requests(requests
);
596 rc
= nbd_opt_read(client
, &request
, sizeof(request
), false, errp
);
600 request
= be16_to_cpu(request
);
601 trace_nbd_negotiate_handle_info_request(request
,
602 nbd_info_lookup(request
));
603 /* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE;
604 * everything else is either a request we don't know or
605 * something we send regardless of request */
610 case NBD_INFO_BLOCK_SIZE
:
615 if (client
->optlen
) {
616 return nbd_reject_length(client
, false, errp
);
619 exp
= nbd_export_find(name
);
621 g_autofree
char *sane_name
= nbd_sanitize_name(name
);
623 return nbd_negotiate_send_rep_err(client
, NBD_REP_ERR_UNKNOWN
,
624 errp
, "export '%s' not present",
628 /* Don't bother sending NBD_INFO_NAME unless client requested it */
630 rc
= nbd_negotiate_send_info(client
, NBD_INFO_NAME
, namelen
, name
,
637 /* Send NBD_INFO_DESCRIPTION only if available, regardless of
639 if (exp
->description
) {
640 size_t len
= strlen(exp
->description
);
642 assert(len
<= NBD_MAX_STRING_SIZE
);
643 rc
= nbd_negotiate_send_info(client
, NBD_INFO_DESCRIPTION
,
644 len
, exp
->description
, errp
);
650 /* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
651 * according to whether the client requested it, and according to
652 * whether this is OPT_INFO or OPT_GO. */
653 /* minimum - 1 for back-compat, or actual if client will obey it. */
654 if (client
->opt
== NBD_OPT_INFO
|| blocksize
) {
655 check_align
= sizes
[0] = blk_get_request_alignment(exp
->common
.blk
);
659 assert(sizes
[0] <= NBD_MAX_BUFFER_SIZE
);
660 /* preferred - Hard-code to 4096 for now.
661 * TODO: is blk_bs(blk)->bl.opt_transfer appropriate? */
662 sizes
[1] = MAX(4096, sizes
[0]);
663 /* maximum - At most 32M, but smaller as appropriate. */
664 sizes
[2] = MIN(blk_get_max_transfer(exp
->common
.blk
), NBD_MAX_BUFFER_SIZE
);
665 trace_nbd_negotiate_handle_info_block_size(sizes
[0], sizes
[1], sizes
[2]);
666 sizes
[0] = cpu_to_be32(sizes
[0]);
667 sizes
[1] = cpu_to_be32(sizes
[1]);
668 sizes
[2] = cpu_to_be32(sizes
[2]);
669 rc
= nbd_negotiate_send_info(client
, NBD_INFO_BLOCK_SIZE
,
670 sizeof(sizes
), sizes
, errp
);
675 /* Send NBD_INFO_EXPORT always */
676 myflags
= exp
->nbdflags
;
677 if (client
->structured_reply
) {
678 myflags
|= NBD_FLAG_SEND_DF
;
680 trace_nbd_negotiate_new_style_size_flags(exp
->size
, myflags
);
681 stq_be_p(buf
, exp
->size
);
682 stw_be_p(buf
+ 8, myflags
);
683 rc
= nbd_negotiate_send_info(client
, NBD_INFO_EXPORT
,
684 sizeof(buf
), buf
, errp
);
690 * If the client is just asking for NBD_OPT_INFO, but forgot to
691 * request block sizes in a situation that would impact
692 * performance, then return an error. But for NBD_OPT_GO, we
693 * tolerate all clients, regardless of alignments.
695 if (client
->opt
== NBD_OPT_INFO
&& !blocksize
&&
696 blk_get_request_alignment(exp
->common
.blk
) > 1) {
697 return nbd_negotiate_send_rep_err(client
,
698 NBD_REP_ERR_BLOCK_SIZE_REQD
,
700 "request NBD_INFO_BLOCK_SIZE to "
705 rc
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
710 if (client
->opt
== NBD_OPT_GO
) {
712 client
->check_align
= check_align
;
713 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
714 blk_exp_ref(&client
->exp
->common
);
715 nbd_check_meta_export(client
);
722 /* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the
723 * new channel for all further (now-encrypted) communication. */
724 static QIOChannel
*nbd_negotiate_handle_starttls(NBDClient
*client
,
729 struct NBDTLSHandshakeData data
= { 0 };
731 assert(client
->opt
== NBD_OPT_STARTTLS
);
733 trace_nbd_negotiate_handle_starttls();
736 if (nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
) < 0) {
740 tioc
= qio_channel_tls_new_server(ioc
,
748 qio_channel_set_name(QIO_CHANNEL(tioc
), "nbd-server-tls");
749 trace_nbd_negotiate_handle_starttls_handshake();
750 data
.loop
= g_main_loop_new(g_main_context_default(), FALSE
);
751 qio_channel_tls_handshake(tioc
,
757 if (!data
.complete
) {
758 g_main_loop_run(data
.loop
);
760 g_main_loop_unref(data
.loop
);
762 object_unref(OBJECT(tioc
));
763 error_propagate(errp
, data
.error
);
767 return QIO_CHANNEL(tioc
);
770 /* nbd_negotiate_send_meta_context
772 * Send one chunk of reply to NBD_OPT_{LIST,SET}_META_CONTEXT
774 * For NBD_OPT_LIST_META_CONTEXT @context_id is ignored, 0 is used instead.
776 static int nbd_negotiate_send_meta_context(NBDClient
*client
,
781 NBDOptionReplyMetaContext opt
;
782 struct iovec iov
[] = {
783 {.iov_base
= &opt
, .iov_len
= sizeof(opt
)},
784 {.iov_base
= (void *)context
, .iov_len
= strlen(context
)}
787 assert(iov
[1].iov_len
<= NBD_MAX_STRING_SIZE
);
788 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
792 trace_nbd_negotiate_meta_query_reply(context
, context_id
);
793 set_be_option_rep(&opt
.h
, client
->opt
, NBD_REP_META_CONTEXT
,
794 sizeof(opt
) - sizeof(opt
.h
) + iov
[1].iov_len
);
795 stl_be_p(&opt
.context_id
, context_id
);
797 return qio_channel_writev_all(client
->ioc
, iov
, 2, errp
) < 0 ? -EIO
: 0;
801 * Return true if @query matches @pattern, or if @query is empty when
802 * the @client is performing _LIST_.
804 static bool nbd_meta_empty_or_pattern(NBDClient
*client
, const char *pattern
,
808 trace_nbd_negotiate_meta_query_parse("empty");
809 return client
->opt
== NBD_OPT_LIST_META_CONTEXT
;
811 if (strcmp(query
, pattern
) == 0) {
812 trace_nbd_negotiate_meta_query_parse(pattern
);
815 trace_nbd_negotiate_meta_query_skip("pattern not matched");
820 * Return true and adjust @str in place if it begins with @prefix.
822 static bool nbd_strshift(const char **str
, const char *prefix
)
824 size_t len
= strlen(prefix
);
826 if (strncmp(*str
, prefix
, len
) == 0) {
833 /* nbd_meta_base_query
835 * Handle queries to 'base' namespace. For now, only the base:allocation
836 * context is available. Return true if @query has been handled.
838 static bool nbd_meta_base_query(NBDClient
*client
, NBDExportMetaContexts
*meta
,
841 if (!nbd_strshift(&query
, "base:")) {
844 trace_nbd_negotiate_meta_query_parse("base:");
846 if (nbd_meta_empty_or_pattern(client
, "allocation", query
)) {
847 meta
->base_allocation
= true;
852 /* nbd_meta_qemu_query
854 * Handle queries to 'qemu' namespace. For now, only the qemu:dirty-bitmap:
855 * context is available. Return true if @query has been handled.
857 static bool nbd_meta_qemu_query(NBDClient
*client
, NBDExportMetaContexts
*meta
,
860 if (!nbd_strshift(&query
, "qemu:")) {
863 trace_nbd_negotiate_meta_query_parse("qemu:");
866 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
867 meta
->bitmap
= !!meta
->exp
->export_bitmap
;
869 trace_nbd_negotiate_meta_query_parse("empty");
873 if (nbd_strshift(&query
, "dirty-bitmap:")) {
874 trace_nbd_negotiate_meta_query_parse("dirty-bitmap:");
875 if (!meta
->exp
->export_bitmap
) {
876 trace_nbd_negotiate_meta_query_skip("no dirty-bitmap exported");
879 if (nbd_meta_empty_or_pattern(client
,
880 meta
->exp
->export_bitmap_context
+
881 strlen("qemu:dirty-bitmap:"), query
)) {
887 trace_nbd_negotiate_meta_query_skip("not dirty-bitmap");
891 /* nbd_negotiate_meta_query
893 * Parse namespace name and call corresponding function to parse body of the
896 * The only supported namespaces are 'base' and 'qemu'.
898 * Return -errno on I/O error, 0 if option was completely handled by
899 * sending a reply about inconsistent lengths, or 1 on success. */
900 static int nbd_negotiate_meta_query(NBDClient
*client
,
901 NBDExportMetaContexts
*meta
, Error
**errp
)
904 g_autofree
char *query
= NULL
;
907 ret
= nbd_opt_read(client
, &len
, sizeof(len
), false, errp
);
911 len
= cpu_to_be32(len
);
913 if (len
> NBD_MAX_STRING_SIZE
) {
914 trace_nbd_negotiate_meta_query_skip("length too long");
915 return nbd_opt_skip(client
, len
, errp
);
918 query
= g_malloc(len
+ 1);
919 ret
= nbd_opt_read(client
, query
, len
, true, errp
);
925 if (nbd_meta_base_query(client
, meta
, query
)) {
928 if (nbd_meta_qemu_query(client
, meta
, query
)) {
932 trace_nbd_negotiate_meta_query_skip("unknown namespace");
936 /* nbd_negotiate_meta_queries
937 * Handle NBD_OPT_LIST_META_CONTEXT and NBD_OPT_SET_META_CONTEXT
939 * Return -errno on I/O error, or 0 if option was completely handled. */
940 static int nbd_negotiate_meta_queries(NBDClient
*client
,
941 NBDExportMetaContexts
*meta
, Error
**errp
)
944 g_autofree
char *export_name
= NULL
;
945 NBDExportMetaContexts local_meta
;
949 if (!client
->structured_reply
) {
950 return nbd_opt_invalid(client
, errp
,
951 "request option '%s' when structured reply "
953 nbd_opt_lookup(client
->opt
));
956 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
) {
957 /* Only change the caller's meta on SET. */
961 memset(meta
, 0, sizeof(*meta
));
963 ret
= nbd_opt_read_name(client
, &export_name
, NULL
, errp
);
968 meta
->exp
= nbd_export_find(export_name
);
969 if (meta
->exp
== NULL
) {
970 g_autofree
char *sane_name
= nbd_sanitize_name(export_name
);
972 return nbd_opt_drop(client
, NBD_REP_ERR_UNKNOWN
, errp
,
973 "export '%s' not present", sane_name
);
976 ret
= nbd_opt_read(client
, &nb_queries
, sizeof(nb_queries
), false, errp
);
980 nb_queries
= cpu_to_be32(nb_queries
);
981 trace_nbd_negotiate_meta_context(nbd_opt_lookup(client
->opt
),
982 export_name
, nb_queries
);
984 if (client
->opt
== NBD_OPT_LIST_META_CONTEXT
&& !nb_queries
) {
985 /* enable all known contexts */
986 meta
->base_allocation
= true;
987 meta
->bitmap
= !!meta
->exp
->export_bitmap
;
989 for (i
= 0; i
< nb_queries
; ++i
) {
990 ret
= nbd_negotiate_meta_query(client
, meta
, errp
);
997 if (meta
->base_allocation
) {
998 ret
= nbd_negotiate_send_meta_context(client
, "base:allocation",
999 NBD_META_ID_BASE_ALLOCATION
,
1007 ret
= nbd_negotiate_send_meta_context(client
,
1008 meta
->exp
->export_bitmap_context
,
1009 NBD_META_ID_DIRTY_BITMAP
,
1016 ret
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
1024 /* nbd_negotiate_options
1025 * Process all NBD_OPT_* client option commands, during fixed newstyle
1028 * -errno on error, errp is set
1029 * 0 on successful negotiation, errp is not set
1030 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
1033 static int nbd_negotiate_options(NBDClient
*client
, Error
**errp
)
1036 bool fixedNewstyle
= false;
1037 bool no_zeroes
= false;
1040 [ 0 .. 3] client flags
1042 Then we loop until NBD_OPT_EXPORT_NAME or NBD_OPT_GO:
1043 [ 0 .. 7] NBD_OPTS_MAGIC
1044 [ 8 .. 11] NBD option
1045 [12 .. 15] Data length
1048 [ 0 .. 7] NBD_OPTS_MAGIC
1049 [ 8 .. 11] Second NBD option
1050 [12 .. 15] Data length
1054 if (nbd_read32(client
->ioc
, &flags
, "flags", errp
) < 0) {
1057 trace_nbd_negotiate_options_flags(flags
);
1058 if (flags
& NBD_FLAG_C_FIXED_NEWSTYLE
) {
1059 fixedNewstyle
= true;
1060 flags
&= ~NBD_FLAG_C_FIXED_NEWSTYLE
;
1062 if (flags
& NBD_FLAG_C_NO_ZEROES
) {
1064 flags
&= ~NBD_FLAG_C_NO_ZEROES
;
1067 error_setg(errp
, "Unknown client flags 0x%" PRIx32
" received", flags
);
1073 uint32_t option
, length
;
1076 if (nbd_read64(client
->ioc
, &magic
, "opts magic", errp
) < 0) {
1079 trace_nbd_negotiate_options_check_magic(magic
);
1080 if (magic
!= NBD_OPTS_MAGIC
) {
1081 error_setg(errp
, "Bad magic received");
1085 if (nbd_read32(client
->ioc
, &option
, "option", errp
) < 0) {
1088 client
->opt
= option
;
1090 if (nbd_read32(client
->ioc
, &length
, "option length", errp
) < 0) {
1093 assert(!client
->optlen
);
1094 client
->optlen
= length
;
1096 if (length
> NBD_MAX_BUFFER_SIZE
) {
1097 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
1098 length
, NBD_MAX_BUFFER_SIZE
);
1102 trace_nbd_negotiate_options_check_option(option
,
1103 nbd_opt_lookup(option
));
1104 if (client
->tlscreds
&&
1105 client
->ioc
== (QIOChannel
*)client
->sioc
) {
1107 if (!fixedNewstyle
) {
1108 error_setg(errp
, "Unsupported option 0x%" PRIx32
, option
);
1112 case NBD_OPT_STARTTLS
:
1114 /* Unconditionally drop the connection if the client
1115 * can't start a TLS negotiation correctly */
1116 return nbd_reject_length(client
, true, errp
);
1118 tioc
= nbd_negotiate_handle_starttls(client
, errp
);
1123 object_unref(OBJECT(client
->ioc
));
1124 client
->ioc
= QIO_CHANNEL(tioc
);
1127 case NBD_OPT_EXPORT_NAME
:
1128 /* No way to return an error to client, so drop connection */
1129 error_setg(errp
, "Option 0x%x not permitted before TLS",
1134 /* Let the client keep trying, unless they asked to
1135 * quit. Always try to give an error back to the
1136 * client; but when replying to OPT_ABORT, be aware
1137 * that the client may hang up before receiving the
1138 * error, in which case we are fine ignoring the
1139 * resulting EPIPE. */
1140 ret
= nbd_opt_drop(client
, NBD_REP_ERR_TLS_REQD
,
1141 option
== NBD_OPT_ABORT
? NULL
: errp
,
1143 " not permitted before TLS", option
);
1144 if (option
== NBD_OPT_ABORT
) {
1149 } else if (fixedNewstyle
) {
1153 ret
= nbd_reject_length(client
, false, errp
);
1155 ret
= nbd_negotiate_handle_list(client
, errp
);
1160 /* NBD spec says we must try to reply before
1161 * disconnecting, but that we must also tolerate
1162 * guests that don't wait for our reply. */
1163 nbd_negotiate_send_rep(client
, NBD_REP_ACK
, NULL
);
1166 case NBD_OPT_EXPORT_NAME
:
1167 return nbd_negotiate_handle_export_name(client
, no_zeroes
,
1172 ret
= nbd_negotiate_handle_info(client
, errp
);
1174 assert(option
== NBD_OPT_GO
);
1179 case NBD_OPT_STARTTLS
:
1181 ret
= nbd_reject_length(client
, false, errp
);
1182 } else if (client
->tlscreds
) {
1183 ret
= nbd_negotiate_send_rep_err(client
,
1184 NBD_REP_ERR_INVALID
, errp
,
1185 "TLS already enabled");
1187 ret
= nbd_negotiate_send_rep_err(client
,
1188 NBD_REP_ERR_POLICY
, errp
,
1189 "TLS not configured");
1193 case NBD_OPT_STRUCTURED_REPLY
:
1195 ret
= nbd_reject_length(client
, false, errp
);
1196 } else if (client
->structured_reply
) {
1197 ret
= nbd_negotiate_send_rep_err(
1198 client
, NBD_REP_ERR_INVALID
, errp
,
1199 "structured reply already negotiated");
1201 ret
= nbd_negotiate_send_rep(client
, NBD_REP_ACK
, errp
);
1202 client
->structured_reply
= true;
1206 case NBD_OPT_LIST_META_CONTEXT
:
1207 case NBD_OPT_SET_META_CONTEXT
:
1208 ret
= nbd_negotiate_meta_queries(client
, &client
->export_meta
,
1213 ret
= nbd_opt_drop(client
, NBD_REP_ERR_UNSUP
, errp
,
1214 "Unsupported option %" PRIu32
" (%s)",
1215 option
, nbd_opt_lookup(option
));
1220 * If broken new-style we should drop the connection
1221 * for anything except NBD_OPT_EXPORT_NAME
1224 case NBD_OPT_EXPORT_NAME
:
1225 return nbd_negotiate_handle_export_name(client
, no_zeroes
,
1229 error_setg(errp
, "Unsupported option %" PRIu32
" (%s)",
1230 option
, nbd_opt_lookup(option
));
1242 * -errno on error, errp is set
1243 * 0 on successful negotiation, errp is not set
1244 * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
1247 static coroutine_fn
int nbd_negotiate(NBDClient
*client
, Error
**errp
)
1250 char buf
[NBD_OLDSTYLE_NEGOTIATE_SIZE
] = "";
1253 /* Old style negotiation header, no room for options
1254 [ 0 .. 7] passwd ("NBDMAGIC")
1255 [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
1257 [24 .. 27] export flags (zero-extended)
1258 [28 .. 151] reserved (0)
1260 New style negotiation header, client can send options
1261 [ 0 .. 7] passwd ("NBDMAGIC")
1262 [ 8 .. 15] magic (NBD_OPTS_MAGIC)
1263 [16 .. 17] server flags (0)
1264 ....options sent, ending in NBD_OPT_EXPORT_NAME or NBD_OPT_GO....
1267 qio_channel_set_blocking(client
->ioc
, false, NULL
);
1269 trace_nbd_negotiate_begin();
1270 memcpy(buf
, "NBDMAGIC", 8);
1272 stq_be_p(buf
+ 8, NBD_OPTS_MAGIC
);
1273 stw_be_p(buf
+ 16, NBD_FLAG_FIXED_NEWSTYLE
| NBD_FLAG_NO_ZEROES
);
1275 if (nbd_write(client
->ioc
, buf
, 18, errp
) < 0) {
1276 error_prepend(errp
, "write failed: ");
1279 ret
= nbd_negotiate_options(client
, errp
);
1282 error_prepend(errp
, "option negotiation failed: ");
1287 /* Attach the channel to the same AioContext as the export */
1288 if (client
->exp
&& client
->exp
->common
.ctx
) {
1289 qio_channel_attach_aio_context(client
->ioc
, client
->exp
->common
.ctx
);
1292 assert(!client
->optlen
);
1293 trace_nbd_negotiate_success();
1298 static int nbd_receive_request(QIOChannel
*ioc
, NBDRequest
*request
,
1301 uint8_t buf
[NBD_REQUEST_SIZE
];
1305 ret
= nbd_read(ioc
, buf
, sizeof(buf
), "request", errp
);
1311 [ 0 .. 3] magic (NBD_REQUEST_MAGIC)
1312 [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...)
1313 [ 6 .. 7] type (NBD_CMD_READ, ...)
1319 magic
= ldl_be_p(buf
);
1320 request
->flags
= lduw_be_p(buf
+ 4);
1321 request
->type
= lduw_be_p(buf
+ 6);
1322 request
->handle
= ldq_be_p(buf
+ 8);
1323 request
->from
= ldq_be_p(buf
+ 16);
1324 request
->len
= ldl_be_p(buf
+ 24);
1326 trace_nbd_receive_request(magic
, request
->flags
, request
->type
,
1327 request
->from
, request
->len
);
1329 if (magic
!= NBD_REQUEST_MAGIC
) {
1330 error_setg(errp
, "invalid magic (got 0x%" PRIx32
")", magic
);
1336 #define MAX_NBD_REQUESTS 16
1338 void nbd_client_get(NBDClient
*client
)
1343 void nbd_client_put(NBDClient
*client
)
1345 if (--client
->refcount
== 0) {
1346 /* The last reference should be dropped by client->close,
1347 * which is called by client_close.
1349 assert(client
->closing
);
1351 qio_channel_detach_aio_context(client
->ioc
);
1352 object_unref(OBJECT(client
->sioc
));
1353 object_unref(OBJECT(client
->ioc
));
1354 if (client
->tlscreds
) {
1355 object_unref(OBJECT(client
->tlscreds
));
1357 g_free(client
->tlsauthz
);
1359 QTAILQ_REMOVE(&client
->exp
->clients
, client
, next
);
1360 blk_exp_unref(&client
->exp
->common
);
1366 static void client_close(NBDClient
*client
, bool negotiated
)
1368 if (client
->closing
) {
1372 client
->closing
= true;
1374 /* Force requests to finish. They will drop their own references,
1375 * then we'll close the socket and free the NBDClient.
1377 qio_channel_shutdown(client
->ioc
, QIO_CHANNEL_SHUTDOWN_BOTH
,
1380 /* Also tell the client, so that they release their reference. */
1381 if (client
->close_fn
) {
1382 client
->close_fn(client
, negotiated
);
1386 static NBDRequestData
*nbd_request_get(NBDClient
*client
)
1388 NBDRequestData
*req
;
1390 assert(client
->nb_requests
<= MAX_NBD_REQUESTS
- 1);
1391 client
->nb_requests
++;
1393 req
= g_new0(NBDRequestData
, 1);
1394 nbd_client_get(client
);
1395 req
->client
= client
;
1399 static void nbd_request_put(NBDRequestData
*req
)
1401 NBDClient
*client
= req
->client
;
1404 qemu_vfree(req
->data
);
1408 client
->nb_requests
--;
1409 nbd_client_receive_next_request(client
);
1411 nbd_client_put(client
);
1414 static void blk_aio_attached(AioContext
*ctx
, void *opaque
)
1416 NBDExport
*exp
= opaque
;
1419 trace_nbd_blk_aio_attached(exp
->name
, ctx
);
1421 exp
->common
.ctx
= ctx
;
1423 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1424 qio_channel_attach_aio_context(client
->ioc
, ctx
);
1425 if (client
->recv_coroutine
) {
1426 aio_co_schedule(ctx
, client
->recv_coroutine
);
1428 if (client
->send_coroutine
) {
1429 aio_co_schedule(ctx
, client
->send_coroutine
);
1434 static void blk_aio_detach(void *opaque
)
1436 NBDExport
*exp
= opaque
;
1439 trace_nbd_blk_aio_detach(exp
->name
, exp
->common
.ctx
);
1441 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
1442 qio_channel_detach_aio_context(client
->ioc
);
1445 exp
->common
.ctx
= NULL
;
1448 static void nbd_eject_notifier(Notifier
*n
, void *data
)
1450 NBDExport
*exp
= container_of(n
, NBDExport
, eject_notifier
);
1452 blk_exp_request_shutdown(&exp
->common
);
1455 void nbd_export_set_on_eject_blk(BlockExport
*exp
, BlockBackend
*blk
)
1457 NBDExport
*nbd_exp
= container_of(exp
, NBDExport
, common
);
1458 assert(exp
->drv
== &blk_exp_nbd
);
1459 assert(nbd_exp
->eject_notifier_blk
== NULL
);
1462 nbd_exp
->eject_notifier_blk
= blk
;
1463 nbd_exp
->eject_notifier
.notify
= nbd_eject_notifier
;
1464 blk_add_remove_bs_notifier(blk
, &nbd_exp
->eject_notifier
);
1467 static int nbd_export_create(BlockExport
*blk_exp
, BlockExportOptions
*exp_args
,
1470 NBDExport
*exp
= container_of(blk_exp
, NBDExport
, common
);
1471 BlockExportOptionsNbd
*arg
= &exp_args
->u
.nbd
;
1472 BlockBackend
*blk
= blk_exp
->blk
;
1474 uint64_t perm
, shared_perm
;
1475 bool readonly
= !exp_args
->writable
;
1476 bool shared
= !exp_args
->writable
;
1479 assert(exp_args
->type
== BLOCK_EXPORT_TYPE_NBD
);
1481 if (!nbd_server_is_running()) {
1482 error_setg(errp
, "NBD server not running");
1486 if (!arg
->has_name
) {
1487 arg
->name
= exp_args
->node_name
;
1490 if (strlen(arg
->name
) > NBD_MAX_STRING_SIZE
) {
1491 error_setg(errp
, "export name '%s' too long", arg
->name
);
1495 if (arg
->description
&& strlen(arg
->description
) > NBD_MAX_STRING_SIZE
) {
1496 error_setg(errp
, "description '%s' too long", arg
->description
);
1500 if (nbd_export_find(arg
->name
)) {
1501 error_setg(errp
, "NBD server already has export named '%s'", arg
->name
);
1505 size
= blk_getlength(blk
);
1507 error_setg_errno(errp
, -size
,
1508 "Failed to determine the NBD export's length");
1512 /* Don't allow resize while the NBD server is running, otherwise we don't
1513 * care what happens with the node. */
1514 blk_get_perm(blk
, &perm
, &shared_perm
);
1515 ret
= blk_set_perm(blk
, perm
, shared_perm
& ~BLK_PERM_RESIZE
, errp
);
1520 blk_set_allow_aio_context_change(blk
, true);
1522 QTAILQ_INIT(&exp
->clients
);
1523 exp
->name
= g_strdup(arg
->name
);
1524 exp
->description
= g_strdup(arg
->description
);
1525 exp
->nbdflags
= (NBD_FLAG_HAS_FLAGS
| NBD_FLAG_SEND_FLUSH
|
1526 NBD_FLAG_SEND_FUA
| NBD_FLAG_SEND_CACHE
);
1528 exp
->nbdflags
|= NBD_FLAG_READ_ONLY
;
1530 exp
->nbdflags
|= NBD_FLAG_CAN_MULTI_CONN
;
1533 exp
->nbdflags
|= (NBD_FLAG_SEND_TRIM
| NBD_FLAG_SEND_WRITE_ZEROES
|
1534 NBD_FLAG_SEND_FAST_ZERO
);
1536 exp
->size
= QEMU_ALIGN_DOWN(size
, BDRV_SECTOR_SIZE
);
1539 BlockDriverState
*bs
= blk_bs(blk
);
1540 BdrvDirtyBitmap
*bm
= NULL
;
1543 bm
= bdrv_find_dirty_bitmap(bs
, arg
->bitmap
);
1548 bs
= bdrv_filter_or_cow_bs(bs
);
1553 error_setg(errp
, "Bitmap '%s' is not found", arg
->bitmap
);
1557 if (bdrv_dirty_bitmap_check(bm
, BDRV_BITMAP_ALLOW_RO
, errp
)) {
1562 if (readonly
&& bdrv_is_writable(bs
) &&
1563 bdrv_dirty_bitmap_enabled(bm
)) {
1566 "Enabled bitmap '%s' incompatible with readonly export",
1571 bdrv_dirty_bitmap_set_busy(bm
, true);
1572 exp
->export_bitmap
= bm
;
1573 assert(strlen(arg
->bitmap
) <= BDRV_BITMAP_MAX_NAME_SIZE
);
1574 exp
->export_bitmap_context
= g_strdup_printf("qemu:dirty-bitmap:%s",
1576 assert(strlen(exp
->export_bitmap_context
) < NBD_MAX_STRING_SIZE
);
1579 blk_add_aio_context_notifier(blk
, blk_aio_attached
, blk_aio_detach
, exp
);
1581 QTAILQ_INSERT_TAIL(&exports
, exp
, next
);
1587 g_free(exp
->description
);
1591 NBDExport
*nbd_export_find(const char *name
)
1594 QTAILQ_FOREACH(exp
, &exports
, next
) {
1595 if (strcmp(name
, exp
->name
) == 0) {
1604 nbd_export_aio_context(NBDExport
*exp
)
1606 return exp
->common
.ctx
;
1609 static void nbd_export_request_shutdown(BlockExport
*blk_exp
)
1611 NBDExport
*exp
= container_of(blk_exp
, NBDExport
, common
);
1612 NBDClient
*client
, *next
;
1614 blk_exp_ref(&exp
->common
);
1616 * TODO: Should we expand QMP NbdServerRemoveNode enum to allow a
1617 * close mode that stops advertising the export to new clients but
1618 * still permits existing clients to run to completion? Because of
1619 * that possibility, nbd_export_close() can be called more than
1620 * once on an export.
1622 QTAILQ_FOREACH_SAFE(client
, &exp
->clients
, next
, next
) {
1623 client_close(client
, true);
1628 QTAILQ_REMOVE(&exports
, exp
, next
);
1630 blk_exp_unref(&exp
->common
);
1633 static void nbd_export_delete(BlockExport
*blk_exp
)
1635 NBDExport
*exp
= container_of(blk_exp
, NBDExport
, common
);
1637 assert(exp
->name
== NULL
);
1638 assert(QTAILQ_EMPTY(&exp
->clients
));
1640 g_free(exp
->description
);
1641 exp
->description
= NULL
;
1643 if (exp
->common
.blk
) {
1644 if (exp
->eject_notifier_blk
) {
1645 notifier_remove(&exp
->eject_notifier
);
1646 blk_unref(exp
->eject_notifier_blk
);
1648 blk_remove_aio_context_notifier(exp
->common
.blk
, blk_aio_attached
,
1649 blk_aio_detach
, exp
);
1652 if (exp
->export_bitmap
) {
1653 bdrv_dirty_bitmap_set_busy(exp
->export_bitmap
, false);
1654 g_free(exp
->export_bitmap_context
);
1658 const BlockExportDriver blk_exp_nbd
= {
1659 .type
= BLOCK_EXPORT_TYPE_NBD
,
1660 .instance_size
= sizeof(NBDExport
),
1661 .create
= nbd_export_create
,
1662 .delete = nbd_export_delete
,
1663 .request_shutdown
= nbd_export_request_shutdown
,
1666 static int coroutine_fn
nbd_co_send_iov(NBDClient
*client
, struct iovec
*iov
,
1667 unsigned niov
, Error
**errp
)
1671 g_assert(qemu_in_coroutine());
1672 qemu_co_mutex_lock(&client
->send_lock
);
1673 client
->send_coroutine
= qemu_coroutine_self();
1675 ret
= qio_channel_writev_all(client
->ioc
, iov
, niov
, errp
) < 0 ? -EIO
: 0;
1677 client
->send_coroutine
= NULL
;
1678 qemu_co_mutex_unlock(&client
->send_lock
);
1683 static inline void set_be_simple_reply(NBDSimpleReply
*reply
, uint64_t error
,
1686 stl_be_p(&reply
->magic
, NBD_SIMPLE_REPLY_MAGIC
);
1687 stl_be_p(&reply
->error
, error
);
1688 stq_be_p(&reply
->handle
, handle
);
1691 static int nbd_co_send_simple_reply(NBDClient
*client
,
1698 NBDSimpleReply reply
;
1699 int nbd_err
= system_errno_to_nbd_errno(error
);
1700 struct iovec iov
[] = {
1701 {.iov_base
= &reply
, .iov_len
= sizeof(reply
)},
1702 {.iov_base
= data
, .iov_len
= len
}
1705 trace_nbd_co_send_simple_reply(handle
, nbd_err
, nbd_err_lookup(nbd_err
),
1707 set_be_simple_reply(&reply
, nbd_err
, handle
);
1709 return nbd_co_send_iov(client
, iov
, len
? 2 : 1, errp
);
1712 static inline void set_be_chunk(NBDStructuredReplyChunk
*chunk
, uint16_t flags
,
1713 uint16_t type
, uint64_t handle
, uint32_t length
)
1715 stl_be_p(&chunk
->magic
, NBD_STRUCTURED_REPLY_MAGIC
);
1716 stw_be_p(&chunk
->flags
, flags
);
1717 stw_be_p(&chunk
->type
, type
);
1718 stq_be_p(&chunk
->handle
, handle
);
1719 stl_be_p(&chunk
->length
, length
);
1722 static int coroutine_fn
nbd_co_send_structured_done(NBDClient
*client
,
1726 NBDStructuredReplyChunk chunk
;
1727 struct iovec iov
[] = {
1728 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1731 trace_nbd_co_send_structured_done(handle
);
1732 set_be_chunk(&chunk
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_NONE
, handle
, 0);
1734 return nbd_co_send_iov(client
, iov
, 1, errp
);
1737 static int coroutine_fn
nbd_co_send_structured_read(NBDClient
*client
,
1745 NBDStructuredReadData chunk
;
1746 struct iovec iov
[] = {
1747 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1748 {.iov_base
= data
, .iov_len
= size
}
1752 trace_nbd_co_send_structured_read(handle
, offset
, data
, size
);
1753 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1754 NBD_REPLY_TYPE_OFFSET_DATA
, handle
,
1755 sizeof(chunk
) - sizeof(chunk
.h
) + size
);
1756 stq_be_p(&chunk
.offset
, offset
);
1758 return nbd_co_send_iov(client
, iov
, 2, errp
);
1761 static int coroutine_fn
nbd_co_send_structured_error(NBDClient
*client
,
1767 NBDStructuredError chunk
;
1768 int nbd_err
= system_errno_to_nbd_errno(error
);
1769 struct iovec iov
[] = {
1770 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1771 {.iov_base
= (char *)msg
, .iov_len
= msg
? strlen(msg
) : 0},
1775 trace_nbd_co_send_structured_error(handle
, nbd_err
,
1776 nbd_err_lookup(nbd_err
), msg
? msg
: "");
1777 set_be_chunk(&chunk
.h
, NBD_REPLY_FLAG_DONE
, NBD_REPLY_TYPE_ERROR
, handle
,
1778 sizeof(chunk
) - sizeof(chunk
.h
) + iov
[1].iov_len
);
1779 stl_be_p(&chunk
.error
, nbd_err
);
1780 stw_be_p(&chunk
.message_length
, iov
[1].iov_len
);
1782 return nbd_co_send_iov(client
, iov
, 1 + !!iov
[1].iov_len
, errp
);
1785 /* Do a sparse read and send the structured reply to the client.
1786 * Returns -errno if sending fails. bdrv_block_status_above() failure is
1787 * reported to the client, at which point this function succeeds.
1789 static int coroutine_fn
nbd_co_send_sparse_read(NBDClient
*client
,
1797 NBDExport
*exp
= client
->exp
;
1798 size_t progress
= 0;
1800 while (progress
< size
) {
1802 int status
= bdrv_block_status_above(blk_bs(exp
->common
.blk
), NULL
,
1804 size
- progress
, &pnum
, NULL
,
1809 char *msg
= g_strdup_printf("unable to check for holes: %s",
1812 ret
= nbd_co_send_structured_error(client
, handle
, -status
, msg
,
1817 assert(pnum
&& pnum
<= size
- progress
);
1818 final
= progress
+ pnum
== size
;
1819 if (status
& BDRV_BLOCK_ZERO
) {
1820 NBDStructuredReadHole chunk
;
1821 struct iovec iov
[] = {
1822 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1825 trace_nbd_co_send_structured_read_hole(handle
, offset
+ progress
,
1827 set_be_chunk(&chunk
.h
, final
? NBD_REPLY_FLAG_DONE
: 0,
1828 NBD_REPLY_TYPE_OFFSET_HOLE
,
1829 handle
, sizeof(chunk
) - sizeof(chunk
.h
));
1830 stq_be_p(&chunk
.offset
, offset
+ progress
);
1831 stl_be_p(&chunk
.length
, pnum
);
1832 ret
= nbd_co_send_iov(client
, iov
, 1, errp
);
1834 ret
= blk_pread(exp
->common
.blk
, offset
+ progress
,
1835 data
+ progress
, pnum
);
1837 error_setg_errno(errp
, -ret
, "reading from file failed");
1840 ret
= nbd_co_send_structured_read(client
, handle
, offset
+ progress
,
1841 data
+ progress
, pnum
, final
,
1853 typedef struct NBDExtentArray
{
1855 unsigned int nb_alloc
;
1857 uint64_t total_length
;
1859 bool converted_to_be
;
1862 static NBDExtentArray
*nbd_extent_array_new(unsigned int nb_alloc
)
1864 NBDExtentArray
*ea
= g_new0(NBDExtentArray
, 1);
1866 ea
->nb_alloc
= nb_alloc
;
1867 ea
->extents
= g_new(NBDExtent
, nb_alloc
);
1873 static void nbd_extent_array_free(NBDExtentArray
*ea
)
1875 g_free(ea
->extents
);
1878 G_DEFINE_AUTOPTR_CLEANUP_FUNC(NBDExtentArray
, nbd_extent_array_free
);
1880 /* Further modifications of the array after conversion are abandoned */
1881 static void nbd_extent_array_convert_to_be(NBDExtentArray
*ea
)
1885 assert(!ea
->converted_to_be
);
1886 ea
->can_add
= false;
1887 ea
->converted_to_be
= true;
1889 for (i
= 0; i
< ea
->count
; i
++) {
1890 ea
->extents
[i
].flags
= cpu_to_be32(ea
->extents
[i
].flags
);
1891 ea
->extents
[i
].length
= cpu_to_be32(ea
->extents
[i
].length
);
1896 * Add extent to NBDExtentArray. If extent can't be added (no available space),
1898 * For safety, when returning -1 for the first time, .can_add is set to false,
1899 * further call to nbd_extent_array_add() will crash.
1900 * (to avoid the situation, when after failing to add an extent (returned -1),
1901 * user miss this failure and add another extent, which is successfully added
1902 * (array is full, but new extent may be squashed into the last one), then we
1903 * have invalid array with skipped extent)
1905 static int nbd_extent_array_add(NBDExtentArray
*ea
,
1906 uint32_t length
, uint32_t flags
)
1908 assert(ea
->can_add
);
1914 /* Extend previous extent if flags are the same */
1915 if (ea
->count
> 0 && flags
== ea
->extents
[ea
->count
- 1].flags
) {
1916 uint64_t sum
= (uint64_t)length
+ ea
->extents
[ea
->count
- 1].length
;
1918 if (sum
<= UINT32_MAX
) {
1919 ea
->extents
[ea
->count
- 1].length
= sum
;
1920 ea
->total_length
+= length
;
1925 if (ea
->count
>= ea
->nb_alloc
) {
1926 ea
->can_add
= false;
1930 ea
->total_length
+= length
;
1931 ea
->extents
[ea
->count
] = (NBDExtent
) {.length
= length
, .flags
= flags
};
1937 static int blockstatus_to_extents(BlockDriverState
*bs
, uint64_t offset
,
1938 uint64_t bytes
, NBDExtentArray
*ea
)
1943 int ret
= bdrv_block_status_above(bs
, NULL
, offset
, bytes
, &num
,
1950 flags
= (ret
& BDRV_BLOCK_ALLOCATED
? 0 : NBD_STATE_HOLE
) |
1951 (ret
& BDRV_BLOCK_ZERO
? NBD_STATE_ZERO
: 0);
1953 if (nbd_extent_array_add(ea
, num
, flags
) < 0) {
1965 * nbd_co_send_extents
1967 * @ea is converted to BE by the function
1968 * @last controls whether NBD_REPLY_FLAG_DONE is sent.
1970 static int nbd_co_send_extents(NBDClient
*client
, uint64_t handle
,
1972 bool last
, uint32_t context_id
, Error
**errp
)
1974 NBDStructuredMeta chunk
;
1975 struct iovec iov
[] = {
1976 {.iov_base
= &chunk
, .iov_len
= sizeof(chunk
)},
1977 {.iov_base
= ea
->extents
, .iov_len
= ea
->count
* sizeof(ea
->extents
[0])}
1980 nbd_extent_array_convert_to_be(ea
);
1982 trace_nbd_co_send_extents(handle
, ea
->count
, context_id
, ea
->total_length
,
1984 set_be_chunk(&chunk
.h
, last
? NBD_REPLY_FLAG_DONE
: 0,
1985 NBD_REPLY_TYPE_BLOCK_STATUS
,
1986 handle
, sizeof(chunk
) - sizeof(chunk
.h
) + iov
[1].iov_len
);
1987 stl_be_p(&chunk
.context_id
, context_id
);
1989 return nbd_co_send_iov(client
, iov
, 2, errp
);
1992 /* Get block status from the exported device and send it to the client */
1993 static int nbd_co_send_block_status(NBDClient
*client
, uint64_t handle
,
1994 BlockDriverState
*bs
, uint64_t offset
,
1995 uint32_t length
, bool dont_fragment
,
1996 bool last
, uint32_t context_id
,
2000 unsigned int nb_extents
= dont_fragment
? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS
;
2001 g_autoptr(NBDExtentArray
) ea
= nbd_extent_array_new(nb_extents
);
2003 ret
= blockstatus_to_extents(bs
, offset
, length
, ea
);
2005 return nbd_co_send_structured_error(
2006 client
, handle
, -ret
, "can't get block status", errp
);
2009 return nbd_co_send_extents(client
, handle
, ea
, last
, context_id
, errp
);
2012 /* Populate @ea from a dirty bitmap. */
2013 static void bitmap_to_extents(BdrvDirtyBitmap
*bitmap
,
2014 uint64_t offset
, uint64_t length
,
2017 int64_t start
, dirty_start
, dirty_count
;
2018 int64_t end
= offset
+ length
;
2021 bdrv_dirty_bitmap_lock(bitmap
);
2023 for (start
= offset
;
2024 bdrv_dirty_bitmap_next_dirty_area(bitmap
, start
, end
, INT32_MAX
,
2025 &dirty_start
, &dirty_count
);
2026 start
= dirty_start
+ dirty_count
)
2028 if ((nbd_extent_array_add(es
, dirty_start
- start
, 0) < 0) ||
2029 (nbd_extent_array_add(es
, dirty_count
, NBD_STATE_DIRTY
) < 0))
2037 /* last non dirty extent */
2038 nbd_extent_array_add(es
, end
- start
, 0);
2041 bdrv_dirty_bitmap_unlock(bitmap
);
2044 static int nbd_co_send_bitmap(NBDClient
*client
, uint64_t handle
,
2045 BdrvDirtyBitmap
*bitmap
, uint64_t offset
,
2046 uint32_t length
, bool dont_fragment
, bool last
,
2047 uint32_t context_id
, Error
**errp
)
2049 unsigned int nb_extents
= dont_fragment
? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS
;
2050 g_autoptr(NBDExtentArray
) ea
= nbd_extent_array_new(nb_extents
);
2052 bitmap_to_extents(bitmap
, offset
, length
, ea
);
2054 return nbd_co_send_extents(client
, handle
, ea
, last
, context_id
, errp
);
2057 /* nbd_co_receive_request
2058 * Collect a client request. Return 0 if request looks valid, -EIO to drop
2059 * connection right away, and any other negative value to report an error to
2060 * the client (although the caller may still need to disconnect after reporting
2063 static int nbd_co_receive_request(NBDRequestData
*req
, NBDRequest
*request
,
2066 NBDClient
*client
= req
->client
;
2069 g_assert(qemu_in_coroutine());
2070 assert(client
->recv_coroutine
== qemu_coroutine_self());
2071 if (nbd_receive_request(client
->ioc
, request
, errp
) < 0) {
2075 trace_nbd_co_receive_request_decode_type(request
->handle
, request
->type
,
2076 nbd_cmd_lookup(request
->type
));
2078 if (request
->type
!= NBD_CMD_WRITE
) {
2079 /* No payload, we are ready to read the next request. */
2080 req
->complete
= true;
2083 if (request
->type
== NBD_CMD_DISC
) {
2084 /* Special case: we're going to disconnect without a reply,
2085 * whether or not flags, from, or len are bogus */
2089 if (request
->type
== NBD_CMD_READ
|| request
->type
== NBD_CMD_WRITE
||
2090 request
->type
== NBD_CMD_CACHE
)
2092 if (request
->len
> NBD_MAX_BUFFER_SIZE
) {
2093 error_setg(errp
, "len (%" PRIu32
" ) is larger than max len (%u)",
2094 request
->len
, NBD_MAX_BUFFER_SIZE
);
2098 if (request
->type
!= NBD_CMD_CACHE
) {
2099 req
->data
= blk_try_blockalign(client
->exp
->common
.blk
,
2101 if (req
->data
== NULL
) {
2102 error_setg(errp
, "No memory");
2108 if (request
->type
== NBD_CMD_WRITE
) {
2109 if (nbd_read(client
->ioc
, req
->data
, request
->len
, "CMD_WRITE data",
2114 req
->complete
= true;
2116 trace_nbd_co_receive_request_payload_received(request
->handle
,
2120 /* Sanity checks. */
2121 if (client
->exp
->nbdflags
& NBD_FLAG_READ_ONLY
&&
2122 (request
->type
== NBD_CMD_WRITE
||
2123 request
->type
== NBD_CMD_WRITE_ZEROES
||
2124 request
->type
== NBD_CMD_TRIM
)) {
2125 error_setg(errp
, "Export is read-only");
2128 if (request
->from
> client
->exp
->size
||
2129 request
->len
> client
->exp
->size
- request
->from
) {
2130 error_setg(errp
, "operation past EOF; From: %" PRIu64
", Len: %" PRIu32
2131 ", Size: %" PRIu64
, request
->from
, request
->len
,
2133 return (request
->type
== NBD_CMD_WRITE
||
2134 request
->type
== NBD_CMD_WRITE_ZEROES
) ? -ENOSPC
: -EINVAL
;
2136 if (client
->check_align
&& !QEMU_IS_ALIGNED(request
->from
| request
->len
,
2137 client
->check_align
)) {
2139 * The block layer gracefully handles unaligned requests, but
2140 * it's still worth tracing client non-compliance
2142 trace_nbd_co_receive_align_compliance(nbd_cmd_lookup(request
->type
),
2145 client
->check_align
);
2147 valid_flags
= NBD_CMD_FLAG_FUA
;
2148 if (request
->type
== NBD_CMD_READ
&& client
->structured_reply
) {
2149 valid_flags
|= NBD_CMD_FLAG_DF
;
2150 } else if (request
->type
== NBD_CMD_WRITE_ZEROES
) {
2151 valid_flags
|= NBD_CMD_FLAG_NO_HOLE
| NBD_CMD_FLAG_FAST_ZERO
;
2152 } else if (request
->type
== NBD_CMD_BLOCK_STATUS
) {
2153 valid_flags
|= NBD_CMD_FLAG_REQ_ONE
;
2155 if (request
->flags
& ~valid_flags
) {
2156 error_setg(errp
, "unsupported flags for command %s (got 0x%x)",
2157 nbd_cmd_lookup(request
->type
), request
->flags
);
2164 /* Send simple reply without a payload, or a structured error
2165 * @error_msg is ignored if @ret >= 0
2166 * Returns 0 if connection is still live, -errno on failure to talk to client
2168 static coroutine_fn
int nbd_send_generic_reply(NBDClient
*client
,
2171 const char *error_msg
,
2174 if (client
->structured_reply
&& ret
< 0) {
2175 return nbd_co_send_structured_error(client
, handle
, -ret
, error_msg
,
2178 return nbd_co_send_simple_reply(client
, handle
, ret
< 0 ? -ret
: 0,
2183 /* Handle NBD_CMD_READ request.
2184 * Return -errno if sending fails. Other errors are reported directly to the
2185 * client as an error reply. */
2186 static coroutine_fn
int nbd_do_cmd_read(NBDClient
*client
, NBDRequest
*request
,
2187 uint8_t *data
, Error
**errp
)
2190 NBDExport
*exp
= client
->exp
;
2192 assert(request
->type
== NBD_CMD_READ
);
2194 /* XXX: NBD Protocol only documents use of FUA with WRITE */
2195 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2196 ret
= blk_co_flush(exp
->common
.blk
);
2198 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2199 "flush failed", errp
);
2203 if (client
->structured_reply
&& !(request
->flags
& NBD_CMD_FLAG_DF
) &&
2206 return nbd_co_send_sparse_read(client
, request
->handle
, request
->from
,
2207 data
, request
->len
, errp
);
2210 ret
= blk_pread(exp
->common
.blk
, request
->from
, data
, request
->len
);
2212 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2213 "reading from file failed", errp
);
2216 if (client
->structured_reply
) {
2218 return nbd_co_send_structured_read(client
, request
->handle
,
2219 request
->from
, data
,
2220 request
->len
, true, errp
);
2222 return nbd_co_send_structured_done(client
, request
->handle
, errp
);
2225 return nbd_co_send_simple_reply(client
, request
->handle
, 0,
2226 data
, request
->len
, errp
);
2233 * Handle NBD_CMD_CACHE request.
2234 * Return -errno if sending fails. Other errors are reported directly to the
2235 * client as an error reply.
2237 static coroutine_fn
int nbd_do_cmd_cache(NBDClient
*client
, NBDRequest
*request
,
2241 NBDExport
*exp
= client
->exp
;
2243 assert(request
->type
== NBD_CMD_CACHE
);
2245 ret
= blk_co_preadv(exp
->common
.blk
, request
->from
, request
->len
,
2246 NULL
, BDRV_REQ_COPY_ON_READ
| BDRV_REQ_PREFETCH
);
2248 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2249 "caching data failed", errp
);
2252 /* Handle NBD request.
2253 * Return -errno if sending fails. Other errors are reported directly to the
2254 * client as an error reply. */
2255 static coroutine_fn
int nbd_handle_request(NBDClient
*client
,
2256 NBDRequest
*request
,
2257 uint8_t *data
, Error
**errp
)
2261 NBDExport
*exp
= client
->exp
;
2264 switch (request
->type
) {
2266 return nbd_do_cmd_cache(client
, request
, errp
);
2269 return nbd_do_cmd_read(client
, request
, data
, errp
);
2273 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2274 flags
|= BDRV_REQ_FUA
;
2276 ret
= blk_pwrite(exp
->common
.blk
, request
->from
, data
, request
->len
,
2278 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2279 "writing to file failed", errp
);
2281 case NBD_CMD_WRITE_ZEROES
:
2283 if (request
->flags
& NBD_CMD_FLAG_FUA
) {
2284 flags
|= BDRV_REQ_FUA
;
2286 if (!(request
->flags
& NBD_CMD_FLAG_NO_HOLE
)) {
2287 flags
|= BDRV_REQ_MAY_UNMAP
;
2289 if (request
->flags
& NBD_CMD_FLAG_FAST_ZERO
) {
2290 flags
|= BDRV_REQ_NO_FALLBACK
;
2293 /* FIXME simplify this when blk_pwrite_zeroes switches to 64-bit */
2294 while (ret
>= 0 && request
->len
) {
2295 int align
= client
->check_align
?: 1;
2296 int len
= MIN(request
->len
, QEMU_ALIGN_DOWN(BDRV_REQUEST_MAX_BYTES
,
2298 ret
= blk_pwrite_zeroes(exp
->common
.blk
, request
->from
, len
, flags
);
2299 request
->len
-= len
;
2300 request
->from
+= len
;
2302 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2303 "writing to file failed", errp
);
2306 /* unreachable, thanks to special case in nbd_co_receive_request() */
2310 ret
= blk_co_flush(exp
->common
.blk
);
2311 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2312 "flush failed", errp
);
2316 /* FIXME simplify this when blk_co_pdiscard switches to 64-bit */
2317 while (ret
>= 0 && request
->len
) {
2318 int align
= client
->check_align
?: 1;
2319 int len
= MIN(request
->len
, QEMU_ALIGN_DOWN(BDRV_REQUEST_MAX_BYTES
,
2321 ret
= blk_co_pdiscard(exp
->common
.blk
, request
->from
, len
);
2322 request
->len
-= len
;
2323 request
->from
+= len
;
2325 if (ret
>= 0 && request
->flags
& NBD_CMD_FLAG_FUA
) {
2326 ret
= blk_co_flush(exp
->common
.blk
);
2328 return nbd_send_generic_reply(client
, request
->handle
, ret
,
2329 "discard failed", errp
);
2331 case NBD_CMD_BLOCK_STATUS
:
2332 if (!request
->len
) {
2333 return nbd_send_generic_reply(client
, request
->handle
, -EINVAL
,
2334 "need non-zero length", errp
);
2336 if (client
->export_meta
.valid
&&
2337 (client
->export_meta
.base_allocation
||
2338 client
->export_meta
.bitmap
))
2340 bool dont_fragment
= request
->flags
& NBD_CMD_FLAG_REQ_ONE
;
2342 if (client
->export_meta
.base_allocation
) {
2343 ret
= nbd_co_send_block_status(client
, request
->handle
,
2344 blk_bs(exp
->common
.blk
),
2346 request
->len
, dont_fragment
,
2347 !client
->export_meta
.bitmap
,
2348 NBD_META_ID_BASE_ALLOCATION
,
2355 if (client
->export_meta
.bitmap
) {
2356 ret
= nbd_co_send_bitmap(client
, request
->handle
,
2357 client
->exp
->export_bitmap
,
2358 request
->from
, request
->len
,
2360 true, NBD_META_ID_DIRTY_BITMAP
, errp
);
2368 return nbd_send_generic_reply(client
, request
->handle
, -EINVAL
,
2369 "CMD_BLOCK_STATUS not negotiated",
2374 msg
= g_strdup_printf("invalid request type (%" PRIu32
") received",
2376 ret
= nbd_send_generic_reply(client
, request
->handle
, -EINVAL
, msg
,
2383 /* Owns a reference to the NBDClient passed as opaque. */
2384 static coroutine_fn
void nbd_trip(void *opaque
)
2386 NBDClient
*client
= opaque
;
2387 NBDRequestData
*req
;
2388 NBDRequest request
= { 0 }; /* GCC thinks it can be used uninitialized */
2390 Error
*local_err
= NULL
;
2393 if (client
->closing
) {
2394 nbd_client_put(client
);
2398 req
= nbd_request_get(client
);
2399 ret
= nbd_co_receive_request(req
, &request
, &local_err
);
2400 client
->recv_coroutine
= NULL
;
2402 if (client
->closing
) {
2404 * The client may be closed when we are blocked in
2405 * nbd_co_receive_request()
2410 nbd_client_receive_next_request(client
);
2416 /* It wans't -EIO, so, according to nbd_co_receive_request()
2417 * semantics, we should return the error to the client. */
2418 Error
*export_err
= local_err
;
2421 ret
= nbd_send_generic_reply(client
, request
.handle
, -EINVAL
,
2422 error_get_pretty(export_err
), &local_err
);
2423 error_free(export_err
);
2425 ret
= nbd_handle_request(client
, &request
, req
->data
, &local_err
);
2428 error_prepend(&local_err
, "Failed to send reply: ");
2432 /* We must disconnect after NBD_CMD_WRITE if we did not
2435 if (!req
->complete
) {
2436 error_setg(&local_err
, "Request handling failed in intermediate state");
2441 nbd_request_put(req
);
2442 nbd_client_put(client
);
2447 error_reportf_err(local_err
, "Disconnect client, due to: ");
2449 nbd_request_put(req
);
2450 client_close(client
, true);
2451 nbd_client_put(client
);
2454 static void nbd_client_receive_next_request(NBDClient
*client
)
2456 if (!client
->recv_coroutine
&& client
->nb_requests
< MAX_NBD_REQUESTS
) {
2457 nbd_client_get(client
);
2458 client
->recv_coroutine
= qemu_coroutine_create(nbd_trip
, client
);
2459 aio_co_schedule(client
->exp
->common
.ctx
, client
->recv_coroutine
);
2463 static coroutine_fn
void nbd_co_client_start(void *opaque
)
2465 NBDClient
*client
= opaque
;
2466 Error
*local_err
= NULL
;
2468 qemu_co_mutex_init(&client
->send_lock
);
2470 if (nbd_negotiate(client
, &local_err
)) {
2472 error_report_err(local_err
);
2474 client_close(client
, false);
2478 nbd_client_receive_next_request(client
);
2482 * Create a new client listener using the given channel @sioc.
2483 * Begin servicing it in a coroutine. When the connection closes, call
2484 * @close_fn with an indication of whether the client completed negotiation.
2486 void nbd_client_new(QIOChannelSocket
*sioc
,
2487 QCryptoTLSCreds
*tlscreds
,
2488 const char *tlsauthz
,
2489 void (*close_fn
)(NBDClient
*, bool))
2494 client
= g_new0(NBDClient
, 1);
2495 client
->refcount
= 1;
2496 client
->tlscreds
= tlscreds
;
2498 object_ref(OBJECT(client
->tlscreds
));
2500 client
->tlsauthz
= g_strdup(tlsauthz
);
2501 client
->sioc
= sioc
;
2502 object_ref(OBJECT(client
->sioc
));
2503 client
->ioc
= QIO_CHANNEL(sioc
);
2504 object_ref(OBJECT(client
->ioc
));
2505 client
->close_fn
= close_fn
;
2507 co
= qemu_coroutine_create(nbd_co_client_start
, client
);
2508 qemu_coroutine_enter(co
);