2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
4 * Network Block Device Server Side
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; under version 2 of the License.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 #include "qemu/osdep.h"
20 #include "qapi/error.h"
21 #include "nbd-internal.h"
23 static int system_errno_to_nbd_errno(int err
)
47 /* Definitions for opaque data types */
49 typedef struct NBDRequest NBDRequest
;
52 QSIMPLEQ_ENTRY(NBDRequest
) entry
;
59 void (*close
)(NBDExport
*exp
);
66 QTAILQ_HEAD(, NBDClient
) clients
;
67 QTAILQ_ENTRY(NBDExport
) next
;
71 Notifier eject_notifier
;
74 static QTAILQ_HEAD(, NBDExport
) exports
= QTAILQ_HEAD_INITIALIZER(exports
);
78 void (*close
)(NBDClient
*client
);
81 QCryptoTLSCreds
*tlscreds
;
83 QIOChannelSocket
*sioc
; /* The underlying data channel */
84 QIOChannel
*ioc
; /* The current I/O channel which may differ (eg TLS) */
86 Coroutine
*recv_coroutine
;
89 Coroutine
*send_coroutine
;
93 QTAILQ_ENTRY(NBDClient
) next
;
98 /* That's all folks */
100 static void nbd_set_handlers(NBDClient
*client
);
101 static void nbd_unset_handlers(NBDClient
*client
);
102 static void nbd_update_can_read(NBDClient
*client
);
104 static gboolean
nbd_negotiate_continue(QIOChannel
*ioc
,
105 GIOCondition condition
,
108 qemu_coroutine_enter(opaque
, NULL
);
112 static ssize_t
nbd_negotiate_read(QIOChannel
*ioc
, void *buffer
, size_t size
)
117 assert(qemu_in_coroutine());
118 /* Negotiation are always in main loop. */
119 watch
= qio_channel_add_watch(ioc
,
121 nbd_negotiate_continue
,
122 qemu_coroutine_self(),
124 ret
= read_sync(ioc
, buffer
, size
);
125 g_source_remove(watch
);
130 static ssize_t
nbd_negotiate_write(QIOChannel
*ioc
, void *buffer
, size_t size
)
135 assert(qemu_in_coroutine());
136 /* Negotiation are always in main loop. */
137 watch
= qio_channel_add_watch(ioc
,
139 nbd_negotiate_continue
,
140 qemu_coroutine_self(),
142 ret
= write_sync(ioc
, buffer
, size
);
143 g_source_remove(watch
);
147 static ssize_t
nbd_negotiate_drop_sync(QIOChannel
*ioc
, size_t size
)
149 ssize_t ret
, dropped
= size
;
150 uint8_t *buffer
= g_malloc(MIN(65536, size
));
153 ret
= nbd_negotiate_read(ioc
, buffer
, MIN(65536, size
));
167 /* Basic flow for negotiation
194 static int nbd_negotiate_send_rep(QIOChannel
*ioc
, uint32_t type
, uint32_t opt
)
199 TRACE("Reply opt=%x type=%x", type
, opt
);
201 magic
= cpu_to_be64(NBD_REP_MAGIC
);
202 if (nbd_negotiate_write(ioc
, &magic
, sizeof(magic
)) != sizeof(magic
)) {
203 LOG("write failed (rep magic)");
206 opt
= cpu_to_be32(opt
);
207 if (nbd_negotiate_write(ioc
, &opt
, sizeof(opt
)) != sizeof(opt
)) {
208 LOG("write failed (rep opt)");
211 type
= cpu_to_be32(type
);
212 if (nbd_negotiate_write(ioc
, &type
, sizeof(type
)) != sizeof(type
)) {
213 LOG("write failed (rep type)");
216 len
= cpu_to_be32(0);
217 if (nbd_negotiate_write(ioc
, &len
, sizeof(len
)) != sizeof(len
)) {
218 LOG("write failed (rep data length)");
224 static int nbd_negotiate_send_rep_list(QIOChannel
*ioc
, NBDExport
*exp
)
226 uint64_t magic
, name_len
;
227 uint32_t opt
, type
, len
;
229 TRACE("Advertizing export name '%s'", exp
->name
? exp
->name
: "");
230 name_len
= strlen(exp
->name
);
231 magic
= cpu_to_be64(NBD_REP_MAGIC
);
232 if (nbd_negotiate_write(ioc
, &magic
, sizeof(magic
)) != sizeof(magic
)) {
233 LOG("write failed (magic)");
236 opt
= cpu_to_be32(NBD_OPT_LIST
);
237 if (nbd_negotiate_write(ioc
, &opt
, sizeof(opt
)) != sizeof(opt
)) {
238 LOG("write failed (opt)");
241 type
= cpu_to_be32(NBD_REP_SERVER
);
242 if (nbd_negotiate_write(ioc
, &type
, sizeof(type
)) != sizeof(type
)) {
243 LOG("write failed (reply type)");
246 len
= cpu_to_be32(name_len
+ sizeof(len
));
247 if (nbd_negotiate_write(ioc
, &len
, sizeof(len
)) != sizeof(len
)) {
248 LOG("write failed (length)");
251 len
= cpu_to_be32(name_len
);
252 if (nbd_negotiate_write(ioc
, &len
, sizeof(len
)) != sizeof(len
)) {
253 LOG("write failed (length)");
256 if (nbd_negotiate_write(ioc
, exp
->name
, name_len
) != name_len
) {
257 LOG("write failed (buffer)");
263 static int nbd_negotiate_handle_list(NBDClient
*client
, uint32_t length
)
268 if (nbd_negotiate_drop_sync(client
->ioc
, length
) != length
) {
271 return nbd_negotiate_send_rep(client
->ioc
,
272 NBD_REP_ERR_INVALID
, NBD_OPT_LIST
);
275 /* For each export, send a NBD_REP_SERVER reply. */
276 QTAILQ_FOREACH(exp
, &exports
, next
) {
277 if (nbd_negotiate_send_rep_list(client
->ioc
, exp
)) {
281 /* Finish with a NBD_REP_ACK. */
282 return nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ACK
, NBD_OPT_LIST
);
285 static int nbd_negotiate_handle_export_name(NBDClient
*client
, uint32_t length
)
291 [20 .. xx] export name (length bytes)
293 TRACE("Checking length");
295 LOG("Bad length received");
298 if (nbd_negotiate_read(client
->ioc
, name
, length
) != length
) {
304 TRACE("Client requested export '%s'", name
);
306 client
->exp
= nbd_export_find(name
);
308 LOG("export not found");
312 QTAILQ_INSERT_TAIL(&client
->exp
->clients
, client
, next
);
313 nbd_export_get(client
->exp
);
320 static QIOChannel
*nbd_negotiate_handle_starttls(NBDClient
*client
,
325 struct NBDTLSHandshakeData data
= { 0 };
327 TRACE("Setting up TLS");
330 if (nbd_negotiate_drop_sync(ioc
, length
) != length
) {
333 nbd_negotiate_send_rep(ioc
, NBD_REP_ERR_INVALID
, NBD_OPT_STARTTLS
);
337 nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ACK
, NBD_OPT_STARTTLS
);
339 tioc
= qio_channel_tls_new_server(ioc
,
347 TRACE("Starting TLS handshake");
348 data
.loop
= g_main_loop_new(g_main_context_default(), FALSE
);
349 qio_channel_tls_handshake(tioc
,
354 if (!data
.complete
) {
355 g_main_loop_run(data
.loop
);
357 g_main_loop_unref(data
.loop
);
359 object_unref(OBJECT(tioc
));
360 error_free(data
.error
);
364 return QIO_CHANNEL(tioc
);
368 static int nbd_negotiate_options(NBDClient
*client
)
371 bool fixedNewstyle
= false;
374 [ 0 .. 3] client flags
376 [ 0 .. 7] NBD_OPTS_MAGIC
377 [ 8 .. 11] NBD option
378 [12 .. 15] Data length
381 [ 0 .. 7] NBD_OPTS_MAGIC
382 [ 8 .. 11] Second NBD option
383 [12 .. 15] Data length
387 if (nbd_negotiate_read(client
->ioc
, &flags
, sizeof(flags
)) !=
392 TRACE("Checking client flags");
393 be32_to_cpus(&flags
);
394 if (flags
& NBD_FLAG_C_FIXED_NEWSTYLE
) {
395 TRACE("Support supports fixed newstyle handshake");
396 fixedNewstyle
= true;
397 flags
&= ~NBD_FLAG_C_FIXED_NEWSTYLE
;
400 TRACE("Unknown client flags 0x%x received", flags
);
406 uint32_t clientflags
, length
;
409 if (nbd_negotiate_read(client
->ioc
, &magic
, sizeof(magic
)) !=
414 TRACE("Checking opts magic");
415 if (magic
!= be64_to_cpu(NBD_OPTS_MAGIC
)) {
416 LOG("Bad magic received");
420 if (nbd_negotiate_read(client
->ioc
, &clientflags
,
421 sizeof(clientflags
)) != sizeof(clientflags
)) {
425 clientflags
= be32_to_cpu(clientflags
);
427 if (nbd_negotiate_read(client
->ioc
, &length
, sizeof(length
)) !=
432 length
= be32_to_cpu(length
);
434 TRACE("Checking option 0x%x", clientflags
);
435 if (client
->tlscreds
&&
436 client
->ioc
== (QIOChannel
*)client
->sioc
) {
438 if (!fixedNewstyle
) {
439 TRACE("Unsupported option 0x%x", clientflags
);
442 switch (clientflags
) {
443 case NBD_OPT_STARTTLS
:
444 tioc
= nbd_negotiate_handle_starttls(client
, length
);
448 object_unref(OBJECT(client
->ioc
));
449 client
->ioc
= QIO_CHANNEL(tioc
);
453 TRACE("Option 0x%x not permitted before TLS", clientflags
);
454 nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ERR_TLS_REQD
,
458 } else if (fixedNewstyle
) {
459 switch (clientflags
) {
461 ret
= nbd_negotiate_handle_list(client
, length
);
470 case NBD_OPT_EXPORT_NAME
:
471 return nbd_negotiate_handle_export_name(client
, length
);
473 case NBD_OPT_STARTTLS
:
474 if (client
->tlscreds
) {
475 TRACE("TLS already enabled");
476 nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ERR_INVALID
,
479 TRACE("TLS not configured");
480 nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ERR_POLICY
,
485 TRACE("Unsupported option 0x%x", clientflags
);
486 if (nbd_negotiate_drop_sync(client
->ioc
, length
) != length
) {
489 nbd_negotiate_send_rep(client
->ioc
, NBD_REP_ERR_UNSUP
,
495 * If broken new-style we should drop the connection
496 * for anything except NBD_OPT_EXPORT_NAME
498 switch (clientflags
) {
499 case NBD_OPT_EXPORT_NAME
:
500 return nbd_negotiate_handle_export_name(client
, length
);
503 TRACE("Unsupported option 0x%x", clientflags
);
515 static coroutine_fn
int nbd_negotiate(NBDClientNewData
*data
)
517 NBDClient
*client
= data
->client
;
518 char buf
[8 + 8 + 8 + 128];
520 const int myflags
= (NBD_FLAG_HAS_FLAGS
| NBD_FLAG_SEND_TRIM
|
521 NBD_FLAG_SEND_FLUSH
| NBD_FLAG_SEND_FUA
);
524 /* Old style negotiation header without options
525 [ 0 .. 7] passwd ("NBDMAGIC")
526 [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
528 [24 .. 25] server flags (0)
529 [26 .. 27] export flags
530 [28 .. 151] reserved (0)
532 New style negotiation header with options
533 [ 0 .. 7] passwd ("NBDMAGIC")
534 [ 8 .. 15] magic (NBD_OPTS_MAGIC)
535 [16 .. 17] server flags (0)
538 [26 .. 27] export flags
539 [28 .. 151] reserved (0)
542 qio_channel_set_blocking(client
->ioc
, false, NULL
);
545 TRACE("Beginning negotiation.");
546 memset(buf
, 0, sizeof(buf
));
547 memcpy(buf
, "NBDMAGIC", 8);
549 oldStyle
= client
->exp
!= NULL
&& !client
->tlscreds
;
551 assert ((client
->exp
->nbdflags
& ~65535) == 0);
552 stq_be_p(buf
+ 8, NBD_CLIENT_MAGIC
);
553 stq_be_p(buf
+ 16, client
->exp
->size
);
554 stw_be_p(buf
+ 26, client
->exp
->nbdflags
| myflags
);
556 stq_be_p(buf
+ 8, NBD_OPTS_MAGIC
);
557 stw_be_p(buf
+ 16, NBD_FLAG_FIXED_NEWSTYLE
);
561 if (client
->tlscreds
) {
562 TRACE("TLS cannot be enabled with oldstyle protocol");
565 if (nbd_negotiate_write(client
->ioc
, buf
, sizeof(buf
)) != sizeof(buf
)) {
570 if (nbd_negotiate_write(client
->ioc
, buf
, 18) != 18) {
574 rc
= nbd_negotiate_options(client
);
576 LOG("option negotiation failed");
580 assert ((client
->exp
->nbdflags
& ~65535) == 0);
581 stq_be_p(buf
+ 18, client
->exp
->size
);
582 stw_be_p(buf
+ 26, client
->exp
->nbdflags
| myflags
);
583 if (nbd_negotiate_write(client
->ioc
, buf
+ 18, sizeof(buf
) - 18) !=
590 TRACE("Negotiation succeeded.");
598 int nbd_disconnect(int fd
)
600 ioctl(fd
, NBD_CLEAR_QUE
);
601 ioctl(fd
, NBD_DISCONNECT
);
602 ioctl(fd
, NBD_CLEAR_SOCK
);
608 int nbd_disconnect(int fd
)
614 static ssize_t
nbd_receive_request(QIOChannel
*ioc
, struct nbd_request
*request
)
616 uint8_t buf
[NBD_REQUEST_SIZE
];
620 ret
= read_sync(ioc
, buf
, sizeof(buf
));
625 if (ret
!= sizeof(buf
)) {
631 [ 0 .. 3] magic (NBD_REQUEST_MAGIC)
632 [ 4 .. 7] type (0 == READ, 1 == WRITE)
638 magic
= be32_to_cpup((uint32_t*)buf
);
639 request
->type
= be32_to_cpup((uint32_t*)(buf
+ 4));
640 request
->handle
= be64_to_cpup((uint64_t*)(buf
+ 8));
641 request
->from
= be64_to_cpup((uint64_t*)(buf
+ 16));
642 request
->len
= be32_to_cpup((uint32_t*)(buf
+ 24));
644 TRACE("Got request: "
645 "{ magic = 0x%x, .type = %d, from = %" PRIu64
" , len = %u }",
646 magic
, request
->type
, request
->from
, request
->len
);
648 if (magic
!= NBD_REQUEST_MAGIC
) {
649 LOG("invalid magic (got 0x%x)", magic
);
655 static ssize_t
nbd_send_reply(QIOChannel
*ioc
, struct nbd_reply
*reply
)
657 uint8_t buf
[NBD_REPLY_SIZE
];
660 reply
->error
= system_errno_to_nbd_errno(reply
->error
);
662 TRACE("Sending response to client: { .error = %d, handle = %" PRIu64
" }",
663 reply
->error
, reply
->handle
);
666 [ 0 .. 3] magic (NBD_REPLY_MAGIC)
667 [ 4 .. 7] error (0 == no error)
670 stl_be_p(buf
, NBD_REPLY_MAGIC
);
671 stl_be_p(buf
+ 4, reply
->error
);
672 stq_be_p(buf
+ 8, reply
->handle
);
674 ret
= write_sync(ioc
, buf
, sizeof(buf
));
679 if (ret
!= sizeof(buf
)) {
680 LOG("writing to socket failed");
686 #define MAX_NBD_REQUESTS 16
688 void nbd_client_get(NBDClient
*client
)
693 void nbd_client_put(NBDClient
*client
)
695 if (--client
->refcount
== 0) {
696 /* The last reference should be dropped by client->close,
697 * which is called by client_close.
699 assert(client
->closing
);
701 nbd_unset_handlers(client
);
702 object_unref(OBJECT(client
->sioc
));
703 object_unref(OBJECT(client
->ioc
));
704 if (client
->tlscreds
) {
705 object_unref(OBJECT(client
->tlscreds
));
707 g_free(client
->tlsaclname
);
709 QTAILQ_REMOVE(&client
->exp
->clients
, client
, next
);
710 nbd_export_put(client
->exp
);
716 static void client_close(NBDClient
*client
)
718 if (client
->closing
) {
722 client
->closing
= true;
724 /* Force requests to finish. They will drop their own references,
725 * then we'll close the socket and free the NBDClient.
727 qio_channel_shutdown(client
->ioc
, QIO_CHANNEL_SHUTDOWN_BOTH
,
730 /* Also tell the client, so that they release their reference. */
732 client
->close(client
);
736 static NBDRequest
*nbd_request_get(NBDClient
*client
)
740 assert(client
->nb_requests
<= MAX_NBD_REQUESTS
- 1);
741 client
->nb_requests
++;
742 nbd_update_can_read(client
);
744 req
= g_new0(NBDRequest
, 1);
745 nbd_client_get(client
);
746 req
->client
= client
;
750 static void nbd_request_put(NBDRequest
*req
)
752 NBDClient
*client
= req
->client
;
755 qemu_vfree(req
->data
);
759 client
->nb_requests
--;
760 nbd_update_can_read(client
);
761 nbd_client_put(client
);
764 static void blk_aio_attached(AioContext
*ctx
, void *opaque
)
766 NBDExport
*exp
= opaque
;
769 TRACE("Export %s: Attaching clients to AIO context %p\n", exp
->name
, ctx
);
773 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
774 nbd_set_handlers(client
);
778 static void blk_aio_detach(void *opaque
)
780 NBDExport
*exp
= opaque
;
783 TRACE("Export %s: Detaching clients from AIO context %p\n", exp
->name
, exp
->ctx
);
785 QTAILQ_FOREACH(client
, &exp
->clients
, next
) {
786 nbd_unset_handlers(client
);
792 static void nbd_eject_notifier(Notifier
*n
, void *data
)
794 NBDExport
*exp
= container_of(n
, NBDExport
, eject_notifier
);
795 nbd_export_close(exp
);
798 NBDExport
*nbd_export_new(BlockBackend
*blk
, off_t dev_offset
, off_t size
,
799 uint32_t nbdflags
, void (*close
)(NBDExport
*),
802 NBDExport
*exp
= g_malloc0(sizeof(NBDExport
));
804 QTAILQ_INIT(&exp
->clients
);
806 exp
->dev_offset
= dev_offset
;
807 exp
->nbdflags
= nbdflags
;
808 exp
->size
= size
< 0 ? blk_getlength(blk
) : size
;
810 error_setg_errno(errp
, -exp
->size
,
811 "Failed to determine the NBD export's length");
814 exp
->size
-= exp
->size
% BDRV_SECTOR_SIZE
;
817 exp
->ctx
= blk_get_aio_context(blk
);
819 blk_add_aio_context_notifier(blk
, blk_aio_attached
, blk_aio_detach
, exp
);
821 exp
->eject_notifier
.notify
= nbd_eject_notifier
;
822 blk_add_remove_bs_notifier(blk
, &exp
->eject_notifier
);
825 * NBD exports are used for non-shared storage migration. Make sure
826 * that BDRV_O_INACTIVE is cleared and the image is ready for write
827 * access since the export could be available before migration handover.
829 aio_context_acquire(exp
->ctx
);
830 blk_invalidate_cache(blk
, NULL
);
831 aio_context_release(exp
->ctx
);
839 NBDExport
*nbd_export_find(const char *name
)
842 QTAILQ_FOREACH(exp
, &exports
, next
) {
843 if (strcmp(name
, exp
->name
) == 0) {
851 void nbd_export_set_name(NBDExport
*exp
, const char *name
)
853 if (exp
->name
== name
) {
858 if (exp
->name
!= NULL
) {
861 QTAILQ_REMOVE(&exports
, exp
, next
);
866 exp
->name
= g_strdup(name
);
867 QTAILQ_INSERT_TAIL(&exports
, exp
, next
);
872 void nbd_export_close(NBDExport
*exp
)
874 NBDClient
*client
, *next
;
877 QTAILQ_FOREACH_SAFE(client
, &exp
->clients
, next
, next
) {
878 client_close(client
);
880 nbd_export_set_name(exp
, NULL
);
884 void nbd_export_get(NBDExport
*exp
)
886 assert(exp
->refcount
> 0);
890 void nbd_export_put(NBDExport
*exp
)
892 assert(exp
->refcount
> 0);
893 if (exp
->refcount
== 1) {
894 nbd_export_close(exp
);
897 if (--exp
->refcount
== 0) {
898 assert(exp
->name
== NULL
);
905 notifier_remove(&exp
->eject_notifier
);
906 blk_remove_aio_context_notifier(exp
->blk
, blk_aio_attached
,
907 blk_aio_detach
, exp
);
916 BlockBackend
*nbd_export_get_blockdev(NBDExport
*exp
)
921 void nbd_export_close_all(void)
923 NBDExport
*exp
, *next
;
925 QTAILQ_FOREACH_SAFE(exp
, &exports
, next
, next
) {
926 nbd_export_close(exp
);
930 static ssize_t
nbd_co_send_reply(NBDRequest
*req
, struct nbd_reply
*reply
,
933 NBDClient
*client
= req
->client
;
936 g_assert(qemu_in_coroutine());
937 qemu_co_mutex_lock(&client
->send_lock
);
938 client
->send_coroutine
= qemu_coroutine_self();
939 nbd_set_handlers(client
);
942 rc
= nbd_send_reply(client
->ioc
, reply
);
944 qio_channel_set_cork(client
->ioc
, true);
945 rc
= nbd_send_reply(client
->ioc
, reply
);
947 ret
= write_sync(client
->ioc
, req
->data
, len
);
952 qio_channel_set_cork(client
->ioc
, false);
955 client
->send_coroutine
= NULL
;
956 nbd_set_handlers(client
);
957 qemu_co_mutex_unlock(&client
->send_lock
);
961 static ssize_t
nbd_co_receive_request(NBDRequest
*req
, struct nbd_request
*request
)
963 NBDClient
*client
= req
->client
;
967 g_assert(qemu_in_coroutine());
968 client
->recv_coroutine
= qemu_coroutine_self();
969 nbd_update_can_read(client
);
971 rc
= nbd_receive_request(client
->ioc
, request
);
979 if ((request
->from
+ request
->len
) < request
->from
) {
980 LOG("integer overflow detected! "
981 "you're probably being attacked");
986 TRACE("Decoding type");
988 command
= request
->type
& NBD_CMD_MASK_COMMAND
;
989 if (command
== NBD_CMD_READ
|| command
== NBD_CMD_WRITE
) {
990 if (request
->len
> NBD_MAX_BUFFER_SIZE
) {
991 LOG("len (%u) is larger than max len (%u)",
992 request
->len
, NBD_MAX_BUFFER_SIZE
);
997 req
->data
= blk_try_blockalign(client
->exp
->blk
, request
->len
);
998 if (req
->data
== NULL
) {
1003 if (command
== NBD_CMD_WRITE
) {
1004 TRACE("Reading %u byte(s)", request
->len
);
1006 if (read_sync(client
->ioc
, req
->data
, request
->len
) != request
->len
) {
1007 LOG("reading from socket failed");
1015 client
->recv_coroutine
= NULL
;
1016 nbd_update_can_read(client
);
1021 static void nbd_trip(void *opaque
)
1023 NBDClient
*client
= opaque
;
1024 NBDExport
*exp
= client
->exp
;
1026 struct nbd_request request
;
1027 struct nbd_reply reply
;
1031 TRACE("Reading request.");
1032 if (client
->closing
) {
1036 req
= nbd_request_get(client
);
1037 ret
= nbd_co_receive_request(req
, &request
);
1038 if (ret
== -EAGAIN
) {
1045 reply
.handle
= request
.handle
;
1052 command
= request
.type
& NBD_CMD_MASK_COMMAND
;
1053 if (command
!= NBD_CMD_DISC
&& (request
.from
+ request
.len
) > exp
->size
) {
1054 LOG("From: %" PRIu64
", Len: %u, Size: %" PRIu64
1055 ", Offset: %" PRIu64
"\n",
1056 request
.from
, request
.len
,
1057 (uint64_t)exp
->size
, (uint64_t)exp
->dev_offset
);
1058 LOG("requested operation past EOF--bad client?");
1059 goto invalid_request
;
1062 if (client
->closing
) {
1064 * The client may be closed when we are blocked in
1065 * nbd_co_receive_request()
1072 TRACE("Request type is READ");
1074 if (request
.type
& NBD_CMD_FLAG_FUA
) {
1075 ret
= blk_co_flush(exp
->blk
);
1077 LOG("flush failed");
1083 ret
= blk_read(exp
->blk
,
1084 (request
.from
+ exp
->dev_offset
) / BDRV_SECTOR_SIZE
,
1085 req
->data
, request
.len
/ BDRV_SECTOR_SIZE
);
1087 LOG("reading from file failed");
1092 TRACE("Read %u byte(s)", request
.len
);
1093 if (nbd_co_send_reply(req
, &reply
, request
.len
) < 0)
1097 TRACE("Request type is WRITE");
1099 if (exp
->nbdflags
& NBD_FLAG_READ_ONLY
) {
1100 TRACE("Server is read-only, return error");
1101 reply
.error
= EROFS
;
1105 TRACE("Writing to device");
1107 ret
= blk_write(exp
->blk
,
1108 (request
.from
+ exp
->dev_offset
) / BDRV_SECTOR_SIZE
,
1109 req
->data
, request
.len
/ BDRV_SECTOR_SIZE
);
1111 LOG("writing to file failed");
1116 if (request
.type
& NBD_CMD_FLAG_FUA
) {
1117 ret
= blk_co_flush(exp
->blk
);
1119 LOG("flush failed");
1125 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
1130 TRACE("Request type is DISCONNECT");
1134 TRACE("Request type is FLUSH");
1136 ret
= blk_co_flush(exp
->blk
);
1138 LOG("flush failed");
1141 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
1146 TRACE("Request type is TRIM");
1147 ret
= blk_co_discard(exp
->blk
, (request
.from
+ exp
->dev_offset
)
1149 request
.len
/ BDRV_SECTOR_SIZE
);
1151 LOG("discard failed");
1154 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
1159 LOG("invalid request type (%u) received", request
.type
);
1161 reply
.error
= EINVAL
;
1163 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
1169 TRACE("Request/Reply complete");
1172 nbd_request_put(req
);
1176 nbd_request_put(req
);
1177 client_close(client
);
1180 static void nbd_read(void *opaque
)
1182 NBDClient
*client
= opaque
;
1184 if (client
->recv_coroutine
) {
1185 qemu_coroutine_enter(client
->recv_coroutine
, NULL
);
1187 qemu_coroutine_enter(qemu_coroutine_create(nbd_trip
), client
);
1191 static void nbd_restart_write(void *opaque
)
1193 NBDClient
*client
= opaque
;
1195 qemu_coroutine_enter(client
->send_coroutine
, NULL
);
1198 static void nbd_set_handlers(NBDClient
*client
)
1200 if (client
->exp
&& client
->exp
->ctx
) {
1201 aio_set_fd_handler(client
->exp
->ctx
, client
->sioc
->fd
,
1203 client
->can_read
? nbd_read
: NULL
,
1204 client
->send_coroutine
? nbd_restart_write
: NULL
,
1209 static void nbd_unset_handlers(NBDClient
*client
)
1211 if (client
->exp
&& client
->exp
->ctx
) {
1212 aio_set_fd_handler(client
->exp
->ctx
, client
->sioc
->fd
,
1213 true, NULL
, NULL
, NULL
);
1217 static void nbd_update_can_read(NBDClient
*client
)
1219 bool can_read
= client
->recv_coroutine
||
1220 client
->nb_requests
< MAX_NBD_REQUESTS
;
1222 if (can_read
!= client
->can_read
) {
1223 client
->can_read
= can_read
;
1224 nbd_set_handlers(client
);
1226 /* There is no need to invoke aio_notify(), since aio_set_fd_handler()
1227 * in nbd_set_handlers() will have taken care of that */
1231 static coroutine_fn
void nbd_co_client_start(void *opaque
)
1233 NBDClientNewData
*data
= opaque
;
1234 NBDClient
*client
= data
->client
;
1235 NBDExport
*exp
= client
->exp
;
1238 nbd_export_get(exp
);
1240 if (nbd_negotiate(data
)) {
1241 client_close(client
);
1244 qemu_co_mutex_init(&client
->send_lock
);
1245 nbd_set_handlers(client
);
1248 QTAILQ_INSERT_TAIL(&exp
->clients
, client
, next
);
1254 void nbd_client_new(NBDExport
*exp
,
1255 QIOChannelSocket
*sioc
,
1256 QCryptoTLSCreds
*tlscreds
,
1257 const char *tlsaclname
,
1258 void (*close_fn
)(NBDClient
*))
1261 NBDClientNewData
*data
= g_new(NBDClientNewData
, 1);
1263 client
= g_malloc0(sizeof(NBDClient
));
1264 client
->refcount
= 1;
1266 client
->tlscreds
= tlscreds
;
1268 object_ref(OBJECT(client
->tlscreds
));
1270 client
->tlsaclname
= g_strdup(tlsaclname
);
1271 client
->sioc
= sioc
;
1272 object_ref(OBJECT(client
->sioc
));
1273 client
->ioc
= QIO_CHANNEL(sioc
);
1274 object_ref(OBJECT(client
->ioc
));
1275 client
->can_read
= true;
1276 client
->close
= close_fn
;
1278 data
->client
= client
;
1279 data
->co
= qemu_coroutine_create(nbd_co_client_start
);
1280 qemu_coroutine_enter(data
->co
, data
);