]>
git.proxmox.com Git - qemu.git/blob - nbd.c
c39692b61f70098097aa25a139a562a71299db6a
2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
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/>.
22 #include "qemu-coroutine.h"
27 #include <sys/ioctl.h>
29 #if defined(__sun__) || defined(__HAIKU__)
30 #include <sys/ioccom.h>
39 #include "qemu_socket.h"
40 #include "qemu-queue.h"
45 #define TRACE(msg, ...) do { \
46 LOG(msg, ## __VA_ARGS__); \
49 #define TRACE(msg, ...) \
53 #define LOG(msg, ...) do { \
54 fprintf(stderr, "%s:%s():L%d: " msg "\n", \
55 __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
58 /* This is all part of the "official" NBD API */
60 #define NBD_REQUEST_SIZE (4 + 4 + 8 + 8 + 4)
61 #define NBD_REPLY_SIZE (4 + 4 + 8)
62 #define NBD_REQUEST_MAGIC 0x25609513
63 #define NBD_REPLY_MAGIC 0x67446698
64 #define NBD_OPTS_MAGIC 0x49484156454F5054LL
65 #define NBD_CLIENT_MAGIC 0x0000420281861253LL
67 #define NBD_SET_SOCK _IO(0xab, 0)
68 #define NBD_SET_BLKSIZE _IO(0xab, 1)
69 #define NBD_SET_SIZE _IO(0xab, 2)
70 #define NBD_DO_IT _IO(0xab, 3)
71 #define NBD_CLEAR_SOCK _IO(0xab, 4)
72 #define NBD_CLEAR_QUE _IO(0xab, 5)
73 #define NBD_PRINT_DEBUG _IO(0xab, 6)
74 #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
75 #define NBD_DISCONNECT _IO(0xab, 8)
76 #define NBD_SET_TIMEOUT _IO(0xab, 9)
77 #define NBD_SET_FLAGS _IO(0xab, 10)
79 #define NBD_OPT_EXPORT_NAME (1 << 0)
81 /* Definitions for opaque data types */
83 typedef struct NBDRequest NBDRequest
;
86 QSIMPLEQ_ENTRY(NBDRequest
) entry
;
97 QTAILQ_HEAD(, NBDClient
) clients
;
98 QSIMPLEQ_HEAD(, NBDRequest
) requests
;
103 void (*close
)(NBDClient
*client
);
108 Coroutine
*recv_coroutine
;
111 Coroutine
*send_coroutine
;
113 QTAILQ_ENTRY(NBDClient
) next
;
118 /* That's all folks */
120 ssize_t
nbd_wr_sync(int fd
, void *buffer
, size_t size
, bool do_read
)
125 if (qemu_in_coroutine()) {
127 return qemu_co_recv(fd
, buffer
, size
);
129 return qemu_co_send(fd
, buffer
, size
);
133 while (offset
< size
) {
137 len
= qemu_recv(fd
, buffer
+ offset
, size
- offset
, 0);
139 len
= send(fd
, buffer
+ offset
, size
- offset
, 0);
143 err
= socket_error();
145 /* recoverable error */
146 if (err
== EINTR
|| (offset
> 0 && err
== EAGAIN
)) {
150 /* unrecoverable error */
165 static ssize_t
read_sync(int fd
, void *buffer
, size_t size
)
167 /* Sockets are kept in blocking mode in the negotiation phase. After
168 * that, a non-readable socket simply means that another thread stole
169 * our request/reply. Synchronization is done with recv_coroutine, so
170 * that this is coroutine-safe.
172 return nbd_wr_sync(fd
, buffer
, size
, true);
175 static ssize_t
write_sync(int fd
, void *buffer
, size_t size
)
179 /* For writes, we do expect the socket to be writable. */
180 ret
= nbd_wr_sync(fd
, buffer
, size
, false);
181 } while (ret
== -EAGAIN
);
185 static void combine_addr(char *buf
, size_t len
, const char* address
,
188 /* If the address-part contains a colon, it's an IPv6 IP so needs [] */
189 if (strstr(address
, ":")) {
190 snprintf(buf
, len
, "[%s]:%u", address
, port
);
192 snprintf(buf
, len
, "%s:%u", address
, port
);
196 int tcp_socket_outgoing(const char *address
, uint16_t port
)
198 char address_and_port
[128];
199 combine_addr(address_and_port
, 128, address
, port
);
200 return tcp_socket_outgoing_spec(address_and_port
);
203 int tcp_socket_outgoing_spec(const char *address_and_port
)
205 return inet_connect(address_and_port
, true, NULL
, NULL
);
208 int tcp_socket_incoming(const char *address
, uint16_t port
)
210 char address_and_port
[128];
211 combine_addr(address_and_port
, 128, address
, port
);
212 return tcp_socket_incoming_spec(address_and_port
);
215 int tcp_socket_incoming_spec(const char *address_and_port
)
219 return inet_listen(address_and_port
, ostr
, olen
, SOCK_STREAM
, 0, NULL
);
222 int unix_socket_incoming(const char *path
)
227 return unix_listen(path
, ostr
, olen
);
230 int unix_socket_outgoing(const char *path
)
232 return unix_connect(path
);
249 static int nbd_send_negotiate(NBDClient
*client
)
251 int csock
= client
->sock
;
252 char buf
[8 + 8 + 8 + 128];
256 [ 0 .. 7] passwd ("NBDMAGIC")
257 [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
260 [28 .. 151] reserved (0)
263 socket_set_block(csock
);
266 TRACE("Beginning negotiation.");
267 memcpy(buf
, "NBDMAGIC", 8);
268 cpu_to_be64w((uint64_t*)(buf
+ 8), NBD_CLIENT_MAGIC
);
269 cpu_to_be64w((uint64_t*)(buf
+ 16), client
->exp
->size
);
270 cpu_to_be32w((uint32_t*)(buf
+ 24),
271 client
->exp
->nbdflags
| NBD_FLAG_HAS_FLAGS
| NBD_FLAG_SEND_TRIM
|
272 NBD_FLAG_SEND_FLUSH
| NBD_FLAG_SEND_FUA
);
273 memset(buf
+ 28, 0, 124);
275 if (write_sync(csock
, buf
, sizeof(buf
)) != sizeof(buf
)) {
280 TRACE("Negotiation succeeded.");
283 socket_set_nonblock(csock
);
287 int nbd_receive_negotiate(int csock
, const char *name
, uint32_t *flags
,
288 off_t
*size
, size_t *blocksize
)
295 TRACE("Receiving negotiation.");
297 socket_set_block(csock
);
300 if (read_sync(csock
, buf
, 8) != 8) {
306 if (strlen(buf
) == 0) {
307 LOG("server connection closed");
311 TRACE("Magic is %c%c%c%c%c%c%c%c",
312 qemu_isprint(buf
[0]) ? buf
[0] : '.',
313 qemu_isprint(buf
[1]) ? buf
[1] : '.',
314 qemu_isprint(buf
[2]) ? buf
[2] : '.',
315 qemu_isprint(buf
[3]) ? buf
[3] : '.',
316 qemu_isprint(buf
[4]) ? buf
[4] : '.',
317 qemu_isprint(buf
[5]) ? buf
[5] : '.',
318 qemu_isprint(buf
[6]) ? buf
[6] : '.',
319 qemu_isprint(buf
[7]) ? buf
[7] : '.');
321 if (memcmp(buf
, "NBDMAGIC", 8) != 0) {
322 LOG("Invalid magic received");
326 if (read_sync(csock
, &magic
, sizeof(magic
)) != sizeof(magic
)) {
330 magic
= be64_to_cpu(magic
);
331 TRACE("Magic is 0x%" PRIx64
, magic
);
334 uint32_t reserved
= 0;
338 TRACE("Checking magic (opts_magic)");
339 if (magic
!= NBD_OPTS_MAGIC
) {
340 LOG("Bad magic received");
343 if (read_sync(csock
, &tmp
, sizeof(tmp
)) != sizeof(tmp
)) {
344 LOG("flags read failed");
347 *flags
= be16_to_cpu(tmp
) << 16;
348 /* reserved for future use */
349 if (write_sync(csock
, &reserved
, sizeof(reserved
)) !=
351 LOG("write failed (reserved)");
354 /* write the export name */
355 magic
= cpu_to_be64(magic
);
356 if (write_sync(csock
, &magic
, sizeof(magic
)) != sizeof(magic
)) {
357 LOG("write failed (magic)");
360 opt
= cpu_to_be32(NBD_OPT_EXPORT_NAME
);
361 if (write_sync(csock
, &opt
, sizeof(opt
)) != sizeof(opt
)) {
362 LOG("write failed (opt)");
365 namesize
= cpu_to_be32(strlen(name
));
366 if (write_sync(csock
, &namesize
, sizeof(namesize
)) !=
368 LOG("write failed (namesize)");
371 if (write_sync(csock
, (char*)name
, strlen(name
)) != strlen(name
)) {
372 LOG("write failed (name)");
376 TRACE("Checking magic (cli_magic)");
378 if (magic
!= NBD_CLIENT_MAGIC
) {
379 LOG("Bad magic received");
384 if (read_sync(csock
, &s
, sizeof(s
)) != sizeof(s
)) {
388 *size
= be64_to_cpu(s
);
390 TRACE("Size is %" PRIu64
, *size
);
393 if (read_sync(csock
, flags
, sizeof(*flags
)) != sizeof(*flags
)) {
394 LOG("read failed (flags)");
397 *flags
= be32_to_cpup(flags
);
399 if (read_sync(csock
, &tmp
, sizeof(tmp
)) != sizeof(tmp
)) {
400 LOG("read failed (tmp)");
403 *flags
|= be32_to_cpu(tmp
);
405 if (read_sync(csock
, &buf
, 124) != 124) {
406 LOG("read failed (buf)");
412 socket_set_nonblock(csock
);
417 int nbd_init(int fd
, int csock
, uint32_t flags
, off_t size
, size_t blocksize
)
419 TRACE("Setting NBD socket");
421 if (ioctl(fd
, NBD_SET_SOCK
, csock
) < 0) {
423 LOG("Failed to set NBD socket");
427 TRACE("Setting block size to %lu", (unsigned long)blocksize
);
429 if (ioctl(fd
, NBD_SET_BLKSIZE
, blocksize
) < 0) {
431 LOG("Failed setting NBD block size");
435 TRACE("Setting size to %zd block(s)", (size_t)(size
/ blocksize
));
437 if (ioctl(fd
, NBD_SET_SIZE_BLOCKS
, size
/ blocksize
) < 0) {
439 LOG("Failed setting size (in blocks)");
443 if (flags
& NBD_FLAG_READ_ONLY
) {
445 TRACE("Setting readonly attribute");
447 if (ioctl(fd
, BLKROSET
, (unsigned long) &read_only
) < 0) {
449 LOG("Failed setting read-only attribute");
454 if (ioctl(fd
, NBD_SET_FLAGS
, flags
) < 0
455 && errno
!= ENOTTY
) {
457 LOG("Failed setting flags");
461 TRACE("Negotiation ended");
466 int nbd_disconnect(int fd
)
468 ioctl(fd
, NBD_CLEAR_QUE
);
469 ioctl(fd
, NBD_DISCONNECT
);
470 ioctl(fd
, NBD_CLEAR_SOCK
);
474 int nbd_client(int fd
)
479 TRACE("Doing NBD loop");
481 ret
= ioctl(fd
, NBD_DO_IT
);
482 if (ret
< 0 && errno
== EPIPE
) {
483 /* NBD_DO_IT normally returns EPIPE when someone has disconnected
484 * the socket via NBD_DISCONNECT. We do not want to return 1 in
491 TRACE("NBD loop returned %d: %s", ret
, strerror(serrno
));
493 TRACE("Clearing NBD queue");
494 ioctl(fd
, NBD_CLEAR_QUE
);
496 TRACE("Clearing NBD socket");
497 ioctl(fd
, NBD_CLEAR_SOCK
);
503 int nbd_init(int fd
, int csock
, uint32_t flags
, off_t size
, size_t blocksize
)
508 int nbd_disconnect(int fd
)
513 int nbd_client(int fd
)
519 ssize_t
nbd_send_request(int csock
, struct nbd_request
*request
)
521 uint8_t buf
[NBD_REQUEST_SIZE
];
524 cpu_to_be32w((uint32_t*)buf
, NBD_REQUEST_MAGIC
);
525 cpu_to_be32w((uint32_t*)(buf
+ 4), request
->type
);
526 cpu_to_be64w((uint64_t*)(buf
+ 8), request
->handle
);
527 cpu_to_be64w((uint64_t*)(buf
+ 16), request
->from
);
528 cpu_to_be32w((uint32_t*)(buf
+ 24), request
->len
);
530 TRACE("Sending request to client: "
531 "{ .from = %" PRIu64
", .len = %u, .handle = %" PRIu64
", .type=%i}",
532 request
->from
, request
->len
, request
->handle
, request
->type
);
534 ret
= write_sync(csock
, buf
, sizeof(buf
));
539 if (ret
!= sizeof(buf
)) {
540 LOG("writing to socket failed");
546 static ssize_t
nbd_receive_request(int csock
, struct nbd_request
*request
)
548 uint8_t buf
[NBD_REQUEST_SIZE
];
552 ret
= read_sync(csock
, buf
, sizeof(buf
));
557 if (ret
!= sizeof(buf
)) {
563 [ 0 .. 3] magic (NBD_REQUEST_MAGIC)
564 [ 4 .. 7] type (0 == READ, 1 == WRITE)
570 magic
= be32_to_cpup((uint32_t*)buf
);
571 request
->type
= be32_to_cpup((uint32_t*)(buf
+ 4));
572 request
->handle
= be64_to_cpup((uint64_t*)(buf
+ 8));
573 request
->from
= be64_to_cpup((uint64_t*)(buf
+ 16));
574 request
->len
= be32_to_cpup((uint32_t*)(buf
+ 24));
576 TRACE("Got request: "
577 "{ magic = 0x%x, .type = %d, from = %" PRIu64
" , len = %u }",
578 magic
, request
->type
, request
->from
, request
->len
);
580 if (magic
!= NBD_REQUEST_MAGIC
) {
581 LOG("invalid magic (got 0x%x)", magic
);
587 ssize_t
nbd_receive_reply(int csock
, struct nbd_reply
*reply
)
589 uint8_t buf
[NBD_REPLY_SIZE
];
593 ret
= read_sync(csock
, buf
, sizeof(buf
));
598 if (ret
!= sizeof(buf
)) {
604 [ 0 .. 3] magic (NBD_REPLY_MAGIC)
605 [ 4 .. 7] error (0 == no error)
609 magic
= be32_to_cpup((uint32_t*)buf
);
610 reply
->error
= be32_to_cpup((uint32_t*)(buf
+ 4));
611 reply
->handle
= be64_to_cpup((uint64_t*)(buf
+ 8));
614 "{ magic = 0x%x, .error = %d, handle = %" PRIu64
" }",
615 magic
, reply
->error
, reply
->handle
);
617 if (magic
!= NBD_REPLY_MAGIC
) {
618 LOG("invalid magic (got 0x%x)", magic
);
624 static ssize_t
nbd_send_reply(int csock
, struct nbd_reply
*reply
)
626 uint8_t buf
[NBD_REPLY_SIZE
];
630 [ 0 .. 3] magic (NBD_REPLY_MAGIC)
631 [ 4 .. 7] error (0 == no error)
634 cpu_to_be32w((uint32_t*)buf
, NBD_REPLY_MAGIC
);
635 cpu_to_be32w((uint32_t*)(buf
+ 4), reply
->error
);
636 cpu_to_be64w((uint64_t*)(buf
+ 8), reply
->handle
);
638 TRACE("Sending response to client");
640 ret
= write_sync(csock
, buf
, sizeof(buf
));
645 if (ret
!= sizeof(buf
)) {
646 LOG("writing to socket failed");
652 #define MAX_NBD_REQUESTS 16
654 void nbd_client_get(NBDClient
*client
)
659 void nbd_client_put(NBDClient
*client
)
661 if (--client
->refcount
== 0) {
662 /* The last reference should be dropped by client->close,
663 * which is called by nbd_client_close.
665 assert(client
->closing
);
667 qemu_set_fd_handler2(client
->sock
, NULL
, NULL
, NULL
, NULL
);
670 QTAILQ_REMOVE(&client
->exp
->clients
, client
, next
);
671 nbd_export_put(client
->exp
);
676 void nbd_client_close(NBDClient
*client
)
678 if (client
->closing
) {
682 client
->closing
= true;
684 /* Force requests to finish. They will drop their own references,
685 * then we'll close the socket and free the NBDClient.
687 shutdown(client
->sock
, 2);
689 /* Also tell the client, so that they release their reference. */
691 client
->close(client
);
695 static NBDRequest
*nbd_request_get(NBDClient
*client
)
698 NBDExport
*exp
= client
->exp
;
700 assert(client
->nb_requests
<= MAX_NBD_REQUESTS
- 1);
701 client
->nb_requests
++;
703 if (QSIMPLEQ_EMPTY(&exp
->requests
)) {
704 req
= g_malloc0(sizeof(NBDRequest
));
705 req
->data
= qemu_blockalign(exp
->bs
, NBD_BUFFER_SIZE
);
707 req
= QSIMPLEQ_FIRST(&exp
->requests
);
708 QSIMPLEQ_REMOVE_HEAD(&exp
->requests
, entry
);
710 nbd_client_get(client
);
711 req
->client
= client
;
715 static void nbd_request_put(NBDRequest
*req
)
717 NBDClient
*client
= req
->client
;
718 QSIMPLEQ_INSERT_HEAD(&client
->exp
->requests
, req
, entry
);
719 if (client
->nb_requests
-- == MAX_NBD_REQUESTS
) {
722 nbd_client_put(client
);
725 NBDExport
*nbd_export_new(BlockDriverState
*bs
, off_t dev_offset
,
726 off_t size
, uint32_t nbdflags
)
728 NBDExport
*exp
= g_malloc0(sizeof(NBDExport
));
729 QSIMPLEQ_INIT(&exp
->requests
);
731 QTAILQ_INIT(&exp
->clients
);
733 exp
->dev_offset
= dev_offset
;
734 exp
->nbdflags
= nbdflags
;
735 exp
->size
= size
== -1 ? bdrv_getlength(bs
) : size
;
739 void nbd_export_close(NBDExport
*exp
)
741 NBDClient
*client
, *next
;
744 QTAILQ_FOREACH_SAFE(client
, &exp
->clients
, next
, next
) {
745 nbd_client_close(client
);
750 void nbd_export_get(NBDExport
*exp
)
752 assert(exp
->refcount
> 0);
756 void nbd_export_put(NBDExport
*exp
)
758 assert(exp
->refcount
> 0);
759 if (exp
->refcount
== 1) {
760 nbd_export_close(exp
);
763 if (--exp
->refcount
== 0) {
764 while (!QSIMPLEQ_EMPTY(&exp
->requests
)) {
765 NBDRequest
*first
= QSIMPLEQ_FIRST(&exp
->requests
);
766 QSIMPLEQ_REMOVE_HEAD(&exp
->requests
, entry
);
767 qemu_vfree(first
->data
);
775 static int nbd_can_read(void *opaque
);
776 static void nbd_read(void *opaque
);
777 static void nbd_restart_write(void *opaque
);
779 static ssize_t
nbd_co_send_reply(NBDRequest
*req
, struct nbd_reply
*reply
,
782 NBDClient
*client
= req
->client
;
783 int csock
= client
->sock
;
786 qemu_co_mutex_lock(&client
->send_lock
);
787 qemu_set_fd_handler2(csock
, nbd_can_read
, nbd_read
,
788 nbd_restart_write
, client
);
789 client
->send_coroutine
= qemu_coroutine_self();
792 rc
= nbd_send_reply(csock
, reply
);
794 socket_set_cork(csock
, 1);
795 rc
= nbd_send_reply(csock
, reply
);
797 ret
= qemu_co_send(csock
, req
->data
, len
);
802 socket_set_cork(csock
, 0);
805 client
->send_coroutine
= NULL
;
806 qemu_set_fd_handler2(csock
, nbd_can_read
, nbd_read
, NULL
, client
);
807 qemu_co_mutex_unlock(&client
->send_lock
);
811 static ssize_t
nbd_co_receive_request(NBDRequest
*req
, struct nbd_request
*request
)
813 NBDClient
*client
= req
->client
;
814 int csock
= client
->sock
;
817 client
->recv_coroutine
= qemu_coroutine_self();
818 rc
= nbd_receive_request(csock
, request
);
826 if (request
->len
> NBD_BUFFER_SIZE
) {
827 LOG("len (%u) is larger than max len (%u)",
828 request
->len
, NBD_BUFFER_SIZE
);
833 if ((request
->from
+ request
->len
) < request
->from
) {
834 LOG("integer overflow detected! "
835 "you're probably being attacked");
840 TRACE("Decoding type");
842 if ((request
->type
& NBD_CMD_MASK_COMMAND
) == NBD_CMD_WRITE
) {
843 TRACE("Reading %u byte(s)", request
->len
);
845 if (qemu_co_recv(csock
, req
->data
, request
->len
) != request
->len
) {
846 LOG("reading from socket failed");
854 client
->recv_coroutine
= NULL
;
858 static void nbd_trip(void *opaque
)
860 NBDClient
*client
= opaque
;
861 NBDExport
*exp
= client
->exp
;
863 struct nbd_request request
;
864 struct nbd_reply reply
;
867 TRACE("Reading request.");
868 if (client
->closing
) {
872 req
= nbd_request_get(client
);
873 ret
= nbd_co_receive_request(req
, &request
);
874 if (ret
== -EAGAIN
) {
881 reply
.handle
= request
.handle
;
889 if ((request
.from
+ request
.len
) > exp
->size
) {
890 LOG("From: %" PRIu64
", Len: %u, Size: %" PRIu64
891 ", Offset: %" PRIu64
"\n",
892 request
.from
, request
.len
,
893 (uint64_t)exp
->size
, (uint64_t)exp
->dev_offset
);
894 LOG("requested operation past EOF--bad client?");
895 goto invalid_request
;
898 switch (request
.type
& NBD_CMD_MASK_COMMAND
) {
900 TRACE("Request type is READ");
902 if (request
.type
& NBD_CMD_FLAG_FUA
) {
903 ret
= bdrv_co_flush(exp
->bs
);
911 ret
= bdrv_read(exp
->bs
, (request
.from
+ exp
->dev_offset
) / 512,
912 req
->data
, request
.len
/ 512);
914 LOG("reading from file failed");
919 TRACE("Read %u byte(s)", request
.len
);
920 if (nbd_co_send_reply(req
, &reply
, request
.len
) < 0)
924 TRACE("Request type is WRITE");
926 if (exp
->nbdflags
& NBD_FLAG_READ_ONLY
) {
927 TRACE("Server is read-only, return error");
932 TRACE("Writing to device");
934 ret
= bdrv_write(exp
->bs
, (request
.from
+ exp
->dev_offset
) / 512,
935 req
->data
, request
.len
/ 512);
937 LOG("writing to file failed");
942 if (request
.type
& NBD_CMD_FLAG_FUA
) {
943 ret
= bdrv_co_flush(exp
->bs
);
951 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
956 TRACE("Request type is DISCONNECT");
960 TRACE("Request type is FLUSH");
962 ret
= bdrv_co_flush(exp
->bs
);
967 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
972 TRACE("Request type is TRIM");
973 ret
= bdrv_co_discard(exp
->bs
, (request
.from
+ exp
->dev_offset
) / 512,
976 LOG("discard failed");
979 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
984 LOG("invalid request type (%u) received", request
.type
);
986 reply
.error
= -EINVAL
;
988 if (nbd_co_send_reply(req
, &reply
, 0) < 0) {
994 TRACE("Request/Reply complete");
997 nbd_request_put(req
);
1001 nbd_request_put(req
);
1002 nbd_client_close(client
);
1005 static int nbd_can_read(void *opaque
)
1007 NBDClient
*client
= opaque
;
1009 return client
->recv_coroutine
|| client
->nb_requests
< MAX_NBD_REQUESTS
;
1012 static void nbd_read(void *opaque
)
1014 NBDClient
*client
= opaque
;
1016 if (client
->recv_coroutine
) {
1017 qemu_coroutine_enter(client
->recv_coroutine
, NULL
);
1019 qemu_coroutine_enter(qemu_coroutine_create(nbd_trip
), client
);
1023 static void nbd_restart_write(void *opaque
)
1025 NBDClient
*client
= opaque
;
1027 qemu_coroutine_enter(client
->send_coroutine
, NULL
);
1030 NBDClient
*nbd_client_new(NBDExport
*exp
, int csock
,
1031 void (*close
)(NBDClient
*))
1034 client
= g_malloc0(sizeof(NBDClient
));
1035 client
->refcount
= 1;
1037 client
->sock
= csock
;
1038 if (nbd_send_negotiate(client
) < 0) {
1042 client
->close
= close
;
1043 qemu_co_mutex_init(&client
->send_lock
);
1044 qemu_set_fd_handler2(csock
, nbd_can_read
, nbd_read
, NULL
, client
);
1046 QTAILQ_INSERT_TAIL(&exp
->clients
, client
, next
);
1047 nbd_export_get(exp
);