1 /*
2 * Copyright Red Hat
3 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
4 *
5 * Network Block Device
6 *
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.
10 *
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.
15 *
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/>.
18 */
19
20 #ifndef NBD_H
21 #define NBD_H
22
23 #include "block/export.h"
24 #include "io/channel-socket.h"
25 #include "crypto/tlscreds.h"
26 #include "qapi/error.h"
27 #include "qemu/bswap.h"
28
29 typedef struct NBDExport NBDExport;
30 typedef struct NBDClient NBDClient;
31 typedef struct NBDClientConnection NBDClientConnection;
32 typedef struct NBDMetaContexts NBDMetaContexts;
33
34 extern const BlockExportDriver blk_exp_nbd;
35
36 /*
37 * NBD_DEFAULT_HANDSHAKE_MAX_SECS: Number of seconds in which client must
38 * succeed at NBD_OPT_GO before being forcefully dropped as too slow.
39 */
40 #define NBD_DEFAULT_HANDSHAKE_MAX_SECS 10
41
42 /*
43 * NBD_DEFAULT_MAX_CONNECTIONS: Number of client sockets to allow at
44 * once; must be large enough to allow a MULTI_CONN-aware client like
45 * nbdcopy to create its typical number of 8-16 sockets.
46 */
47 #define NBD_DEFAULT_MAX_CONNECTIONS 100
48
49 /* Handshake phase structs - this struct is passed on the wire */
50
51 typedef struct NBDOption {
52 uint64_t magic; /* NBD_OPTS_MAGIC */
53 uint32_t option; /* NBD_OPT_* */
54 uint32_t length;
55 } QEMU_PACKED NBDOption;
56
57 typedef struct NBDOptionReply {
58 uint64_t magic; /* NBD_REP_MAGIC */
59 uint32_t option; /* NBD_OPT_* */
60 uint32_t type; /* NBD_REP_* */
61 uint32_t length;
62 } QEMU_PACKED NBDOptionReply;
63
64 typedef struct NBDOptionReplyMetaContext {
65 NBDOptionReply h; /* h.type = NBD_REP_META_CONTEXT, h.length > 4 */
66 uint32_t context_id;
67 /* metadata context name follows */
68 } QEMU_PACKED NBDOptionReplyMetaContext;
69
70 /* Track results of negotiation */
71 typedef enum NBDMode {
72 /* Keep this list in a continuum of increasing features. */
73 NBD_MODE_OLDSTYLE, /* server lacks newstyle negotiation */
74 NBD_MODE_EXPORT_NAME, /* newstyle but only OPT_EXPORT_NAME safe */
75 NBD_MODE_SIMPLE, /* newstyle but only simple replies */
76 NBD_MODE_STRUCTURED, /* newstyle, structured replies enabled */
77 NBD_MODE_EXTENDED, /* newstyle, extended headers enabled */
78 } NBDMode;
79
80 /* Transmission phase structs */
81
82 /*
83 * Note: NBDRequest is _NOT_ the same as the network representation of an NBD
84 * request!
85 */
86 typedef struct NBDRequest {
87 uint64_t cookie;
88 uint64_t from; /* Offset touched by the command */
89 uint64_t len; /* Effect length; 32 bit limit without extended headers */
90 uint16_t flags; /* NBD_CMD_FLAG_* */
91 uint16_t type; /* NBD_CMD_* */
92 NBDMode mode; /* Determines which network representation to use */
93 NBDMetaContexts *contexts; /* Used by NBD_CMD_BLOCK_STATUS */
94 } NBDRequest;
95
96 typedef struct NBDSimpleReply {
97 uint32_t magic; /* NBD_SIMPLE_REPLY_MAGIC */
98 uint32_t error;
99 uint64_t cookie;
100 } QEMU_PACKED NBDSimpleReply;
101
102 /* Header of all structured replies */
103 typedef struct NBDStructuredReplyChunk {
104 uint32_t magic; /* NBD_STRUCTURED_REPLY_MAGIC */
105 uint16_t flags; /* combination of NBD_REPLY_FLAG_* */
106 uint16_t type; /* NBD_REPLY_TYPE_* */
107 uint64_t cookie; /* request handle */
108 uint32_t length; /* length of payload */
109 } QEMU_PACKED NBDStructuredReplyChunk;
110
111 typedef struct NBDExtendedReplyChunk {
112 uint32_t magic; /* NBD_EXTENDED_REPLY_MAGIC */
113 uint16_t flags; /* combination of NBD_REPLY_FLAG_* */
114 uint16_t type; /* NBD_REPLY_TYPE_* */
115 uint64_t cookie; /* request handle */
116 uint64_t offset; /* request offset */
117 uint64_t length; /* length of payload */
118 } QEMU_PACKED NBDExtendedReplyChunk;
119
120 typedef union NBDReply {
121 NBDSimpleReply simple;
122 NBDStructuredReplyChunk structured;
123 NBDExtendedReplyChunk extended;
124 struct {
125 /*
126 * @magic and @cookie fields have the same offset and size in all
127 * forms of replies, so let them be accessible without ".simple.",
128 * ".structured.", or ".extended." specifications.
129 */
130 uint32_t magic;
131 uint32_t _skip;
132 uint64_t cookie;
133 };
134 } NBDReply;
135 QEMU_BUILD_BUG_ON(offsetof(NBDReply, simple.cookie) !=
136 offsetof(NBDReply, cookie));
137 QEMU_BUILD_BUG_ON(offsetof(NBDReply, structured.cookie) !=
138 offsetof(NBDReply, cookie));
139 QEMU_BUILD_BUG_ON(offsetof(NBDReply, extended.cookie) !=
140 offsetof(NBDReply, cookie));
141
142 /* Header of chunk for NBD_REPLY_TYPE_OFFSET_DATA */
143 typedef struct NBDStructuredReadData {
144 /* header's .length >= 9 */
145 uint64_t offset;
146 /* At least one byte of data payload follows, calculated from h.length */
147 } QEMU_PACKED NBDStructuredReadData;
148
149 /* Complete chunk for NBD_REPLY_TYPE_OFFSET_HOLE */
150 typedef struct NBDStructuredReadHole {
151 /* header's length == 12 */
152 uint64_t offset;
153 uint32_t length;
154 } QEMU_PACKED NBDStructuredReadHole;
155
156 /* Header of all NBD_REPLY_TYPE_ERROR* errors */
157 typedef struct NBDStructuredError {
158 /* header's length >= 6 */
159 uint32_t error;
160 uint16_t message_length;
161 } QEMU_PACKED NBDStructuredError;
162
163 /* Header of NBD_REPLY_TYPE_BLOCK_STATUS */
164 typedef struct NBDStructuredMeta {
165 /* header's length >= 12 (at least one extent) */
166 uint32_t context_id;
167 /* NBDExtent32 extents[] follows, array length implied by header */
168 } QEMU_PACKED NBDStructuredMeta;
169
170 /* Extent array element for NBD_REPLY_TYPE_BLOCK_STATUS */
171 typedef struct NBDExtent32 {
172 uint32_t length;
173 uint32_t flags; /* NBD_STATE_* */
174 } QEMU_PACKED NBDExtent32;
175
176 /* Header of NBD_REPLY_TYPE_BLOCK_STATUS_EXT */
177 typedef struct NBDExtendedMeta {
178 /* header's length >= 24 (at least one extent) */
179 uint32_t context_id;
180 uint32_t count; /* header length must be count * 16 + 8 */
181 /* NBDExtent64 extents[count] follows */
182 } QEMU_PACKED NBDExtendedMeta;
183
184 /* Extent array element for NBD_REPLY_TYPE_BLOCK_STATUS_EXT */
185 typedef struct NBDExtent64 {
186 uint64_t length;
187 uint64_t flags; /* NBD_STATE_* */
188 } QEMU_PACKED NBDExtent64;
189
190 /* Client payload for limiting NBD_CMD_BLOCK_STATUS reply */
191 typedef struct NBDBlockStatusPayload {
192 uint64_t effect_length;
193 /* uint32_t ids[] follows, array length implied by header */
194 } QEMU_PACKED NBDBlockStatusPayload;
195
196 /* Transmission (export) flags: sent from server to client during handshake,
197 but describe what will happen during transmission */
198 enum {
199 NBD_FLAG_HAS_FLAGS_BIT = 0, /* Flags are there */
200 NBD_FLAG_READ_ONLY_BIT = 1, /* Device is read-only */
201 NBD_FLAG_SEND_FLUSH_BIT = 2, /* Send FLUSH */
202 NBD_FLAG_SEND_FUA_BIT = 3, /* Send FUA (Force Unit Access) */
203 NBD_FLAG_ROTATIONAL_BIT = 4, /* Use elevator algorithm -
204 rotational media */
205 NBD_FLAG_SEND_TRIM_BIT = 5, /* Send TRIM (discard) */
206 NBD_FLAG_SEND_WRITE_ZEROES_BIT = 6, /* Send WRITE_ZEROES */
207 NBD_FLAG_SEND_DF_BIT = 7, /* Send DF (Do not Fragment) */
208 NBD_FLAG_CAN_MULTI_CONN_BIT = 8, /* Multi-client cache consistent */
209 NBD_FLAG_SEND_RESIZE_BIT = 9, /* Send resize */
210 NBD_FLAG_SEND_CACHE_BIT = 10, /* Send CACHE (prefetch) */
211 NBD_FLAG_SEND_FAST_ZERO_BIT = 11, /* FAST_ZERO flag for WRITE_ZEROES */
212 NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT = 12, /* PAYLOAD flag for BLOCK_STATUS */
213 };
214
215 #define NBD_FLAG_HAS_FLAGS (1 << NBD_FLAG_HAS_FLAGS_BIT)
216 #define NBD_FLAG_READ_ONLY (1 << NBD_FLAG_READ_ONLY_BIT)
217 #define NBD_FLAG_SEND_FLUSH (1 << NBD_FLAG_SEND_FLUSH_BIT)
218 #define NBD_FLAG_SEND_FUA (1 << NBD_FLAG_SEND_FUA_BIT)
219 #define NBD_FLAG_ROTATIONAL (1 << NBD_FLAG_ROTATIONAL_BIT)
220 #define NBD_FLAG_SEND_TRIM (1 << NBD_FLAG_SEND_TRIM_BIT)
221 #define NBD_FLAG_SEND_WRITE_ZEROES (1 << NBD_FLAG_SEND_WRITE_ZEROES_BIT)
222 #define NBD_FLAG_SEND_DF (1 << NBD_FLAG_SEND_DF_BIT)
223 #define NBD_FLAG_CAN_MULTI_CONN (1 << NBD_FLAG_CAN_MULTI_CONN_BIT)
224 #define NBD_FLAG_SEND_RESIZE (1 << NBD_FLAG_SEND_RESIZE_BIT)
225 #define NBD_FLAG_SEND_CACHE (1 << NBD_FLAG_SEND_CACHE_BIT)
226 #define NBD_FLAG_SEND_FAST_ZERO (1 << NBD_FLAG_SEND_FAST_ZERO_BIT)
227 #define NBD_FLAG_BLOCK_STAT_PAYLOAD (1 << NBD_FLAG_BLOCK_STAT_PAYLOAD_BIT)
228
229 /* New-style handshake (global) flags, sent from server to client, and
230 control what will happen during handshake phase. */
231 #define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
232 #define NBD_FLAG_NO_ZEROES (1 << 1) /* End handshake without zeroes. */
233
234 /* New-style client flags, sent from client to server to control what happens
235 during handshake phase. */
236 #define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
237 #define NBD_FLAG_C_NO_ZEROES (1 << 1) /* End handshake without zeroes. */
238
239 /* Option requests. */
240 #define NBD_OPT_EXPORT_NAME (1)
241 #define NBD_OPT_ABORT (2)
242 #define NBD_OPT_LIST (3)
243 /* #define NBD_OPT_PEEK_EXPORT (4) not in use */
244 #define NBD_OPT_STARTTLS (5)
245 #define NBD_OPT_INFO (6)
246 #define NBD_OPT_GO (7)
247 #define NBD_OPT_STRUCTURED_REPLY (8)
248 #define NBD_OPT_LIST_META_CONTEXT (9)
249 #define NBD_OPT_SET_META_CONTEXT (10)
250 #define NBD_OPT_EXTENDED_HEADERS (11)
251
252 /* Option reply types. */
253 #define NBD_REP_ERR(value) ((UINT32_C(1) << 31) | (value))
254
255 #define NBD_REP_ACK (1) /* Data sending finished. */
256 #define NBD_REP_SERVER (2) /* Export description. */
257 #define NBD_REP_INFO (3) /* NBD_OPT_INFO/GO. */
258 #define NBD_REP_META_CONTEXT (4) /* NBD_OPT_{LIST,SET}_META_CONTEXT */
259
260 #define NBD_REP_ERR_UNSUP NBD_REP_ERR(1) /* Unknown option */
261 #define NBD_REP_ERR_POLICY NBD_REP_ERR(2) /* Server denied */
262 #define NBD_REP_ERR_INVALID NBD_REP_ERR(3) /* Invalid length */
263 #define NBD_REP_ERR_PLATFORM NBD_REP_ERR(4) /* Not compiled in */
264 #define NBD_REP_ERR_TLS_REQD NBD_REP_ERR(5) /* TLS required */
265 #define NBD_REP_ERR_UNKNOWN NBD_REP_ERR(6) /* Export unknown */
266 #define NBD_REP_ERR_SHUTDOWN NBD_REP_ERR(7) /* Server shutting down */
267 #define NBD_REP_ERR_BLOCK_SIZE_REQD NBD_REP_ERR(8) /* Need INFO_BLOCK_SIZE */
268 #define NBD_REP_ERR_TOO_BIG NBD_REP_ERR(9) /* Payload size overflow */
269 #define NBD_REP_ERR_EXT_HEADER_REQD NBD_REP_ERR(10) /* Need extended headers */
270
271 /* Info types, used during NBD_REP_INFO */
272 #define NBD_INFO_EXPORT 0
273 #define NBD_INFO_NAME 1
274 #define NBD_INFO_DESCRIPTION 2
275 #define NBD_INFO_BLOCK_SIZE 3
276
277 /* Request flags, sent from client to server during transmission phase */
278 #define NBD_CMD_FLAG_FUA (1 << 0) /* 'force unit access' during write */
279 #define NBD_CMD_FLAG_NO_HOLE (1 << 1) /* don't punch hole on zero run */
280 #define NBD_CMD_FLAG_DF (1 << 2) /* don't fragment structured read */
281 #define NBD_CMD_FLAG_REQ_ONE (1 << 3) \
282 /* only one extent in BLOCK_STATUS reply chunk */
283 #define NBD_CMD_FLAG_FAST_ZERO (1 << 4) /* fail if WRITE_ZEROES is not fast */
284 #define NBD_CMD_FLAG_PAYLOAD_LEN (1 << 5) \
285 /* length describes payload, not effect; only with ext header */
286
287 /* Supported request types */
288 enum {
289 NBD_CMD_READ = 0,
290 NBD_CMD_WRITE = 1,
291 NBD_CMD_DISC = 2,
292 NBD_CMD_FLUSH = 3,
293 NBD_CMD_TRIM = 4,
294 NBD_CMD_CACHE = 5,
295 NBD_CMD_WRITE_ZEROES = 6,
296 NBD_CMD_BLOCK_STATUS = 7,
297 };
298
299 #define NBD_DEFAULT_PORT 10809
300
301 /* Maximum size of a single READ/WRITE data buffer */
302 #define NBD_MAX_BUFFER_SIZE (32 * 1024 * 1024)
303
304 /*
305 * Maximum size of a protocol string (export name, metadata context name,
306 * etc.). Use malloc rather than stack allocation for storage of a
307 * string.
308 */
309 #define NBD_MAX_STRING_SIZE 4096
310
311 /* Two types of request structures, a given client will only use 1 */
312 #define NBD_REQUEST_MAGIC 0x25609513
313 #define NBD_EXTENDED_REQUEST_MAGIC 0x21e41c71
314
315 /*
316 * Three types of reply structures, but what a client expects depends
317 * on NBD_OPT_STRUCTURED_REPLY and NBD_OPT_EXTENDED_HEADERS.
318 */
319 #define NBD_SIMPLE_REPLY_MAGIC 0x67446698
320 #define NBD_STRUCTURED_REPLY_MAGIC 0x668e33ef
321 #define NBD_EXTENDED_REPLY_MAGIC 0x6e8a278c
322
323 /* Chunk reply flags (for structured and extended replies) */
324 #define NBD_REPLY_FLAG_DONE (1 << 0) /* This reply-chunk is last */
325
326 /* Chunk reply types */
327 #define NBD_REPLY_ERR(value) ((1 << 15) | (value))
328
329 #define NBD_REPLY_TYPE_NONE 0
330 #define NBD_REPLY_TYPE_OFFSET_DATA 1
331 #define NBD_REPLY_TYPE_OFFSET_HOLE 2
332 #define NBD_REPLY_TYPE_BLOCK_STATUS 5
333 #define NBD_REPLY_TYPE_BLOCK_STATUS_EXT 6
334 #define NBD_REPLY_TYPE_ERROR NBD_REPLY_ERR(1)
335 #define NBD_REPLY_TYPE_ERROR_OFFSET NBD_REPLY_ERR(2)
336
337 /* Extent flags for base:allocation in NBD_REPLY_TYPE_BLOCK_STATUS */
338 #define NBD_STATE_HOLE (1 << 0)
339 #define NBD_STATE_ZERO (1 << 1)
340
341 /* Extent flags for qemu:dirty-bitmap in NBD_REPLY_TYPE_BLOCK_STATUS */
342 #define NBD_STATE_DIRTY (1 << 0)
343
344 /* No flags needed for qemu:allocation-depth in NBD_REPLY_TYPE_BLOCK_STATUS */
345
nbd_reply_type_is_error(int type)346 static inline bool nbd_reply_type_is_error(int type)
347 {
348 return type & (1 << 15);
349 }
350
351 /* NBD errors are based on errno numbers, so there is a 1:1 mapping,
352 * but only a limited set of errno values is specified in the protocol.
353 * Everything else is squashed to EINVAL.
354 */
355 #define NBD_SUCCESS 0
356 #define NBD_EPERM 1
357 #define NBD_EIO 5
358 #define NBD_ENOMEM 12
359 #define NBD_EINVAL 22
360 #define NBD_ENOSPC 28
361 #define NBD_EOVERFLOW 75
362 #define NBD_ENOTSUP 95
363 #define NBD_ESHUTDOWN 108
364
365 /* Details collected by NBD_OPT_EXPORT_NAME and NBD_OPT_GO */
366 typedef struct NBDExportInfo {
367 /* Set by client before nbd_receive_negotiate() */
368 bool request_sizes;
369 char *x_dirty_bitmap;
370
371 /* Set by client before nbd_receive_negotiate(), or by server results
372 * during nbd_receive_export_list() */
373 char *name; /* must be non-NULL */
374
375 /* In-out fields, set by client before nbd_receive_negotiate() and
376 * updated by server results during nbd_receive_negotiate() */
377 NBDMode mode; /* input maximum mode tolerated; output actual mode chosen */
378 bool base_allocation; /* base:allocation context for NBD_CMD_BLOCK_STATUS */
379
380 /* Set by server results during nbd_receive_negotiate() and
381 * nbd_receive_export_list() */
382 uint64_t size;
383 uint16_t flags;
384 uint32_t min_block;
385 uint32_t opt_block;
386 uint32_t max_block;
387
388 uint32_t context_id;
389
390 /* Set by server results during nbd_receive_export_list() */
391 char *description;
392 int n_contexts;
393 char **contexts;
394 } NBDExportInfo;
395
396 int nbd_receive_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds,
397 const char *hostname, QIOChannel **outioc,
398 NBDExportInfo *info, Error **errp);
399 void nbd_free_export_list(NBDExportInfo *info, int count);
400 int nbd_receive_export_list(QIOChannel *ioc, QCryptoTLSCreds *tlscreds,
401 const char *hostname, NBDExportInfo **info,
402 Error **errp);
403 int nbd_init(int fd, QIOChannelSocket *sioc, NBDExportInfo *info,
404 Error **errp);
405 int nbd_send_request(QIOChannel *ioc, NBDRequest *request);
406 int coroutine_fn nbd_receive_reply(BlockDriverState *bs, QIOChannel *ioc,
407 NBDReply *reply, NBDMode mode,
408 Error **errp);
409 int nbd_client(int fd);
410 int nbd_disconnect(int fd);
411 int nbd_errno_to_system_errno(int err);
412
413 void nbd_export_set_on_eject_blk(BlockExport *exp, BlockBackend *blk);
414
415 AioContext *nbd_export_aio_context(NBDExport *exp);
416 NBDExport *nbd_export_find(const char *name);
417
418 void nbd_client_new(QIOChannelSocket *sioc,
419 uint32_t handshake_max_secs,
420 QCryptoTLSCreds *tlscreds,
421 const char *tlsauthz,
422 void (*close_fn)(NBDClient *, bool),
423 void *owner);
424 void *nbd_client_owner(NBDClient *client);
425 void nbd_client_get(NBDClient *client);
426 void nbd_client_put(NBDClient *client);
427
428 void nbd_server_is_qemu_nbd(int max_connections);
429 bool nbd_server_is_running(void);
430 int nbd_server_max_connections(void);
431 void nbd_server_start(SocketAddress *addr, const char *tls_creds,
432 const char *tls_authz, uint32_t max_connections,
433 Error **errp);
434 void nbd_server_start_options(NbdServerOptions *arg, Error **errp);
435
436 /* nbd_read
437 * Reads @size bytes from @ioc. Returns 0 on success.
438 */
nbd_read(QIOChannel * ioc,void * buffer,size_t size,const char * desc,Error ** errp)439 static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size,
440 const char *desc, Error **errp)
441 {
442 ERRP_GUARD();
443 int ret = qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;
444
445 if (ret < 0) {
446 if (desc) {
447 error_prepend(errp, "Failed to read %s: ", desc);
448 }
449 return ret;
450 }
451
452 return 0;
453 }
454
455 #define DEF_NBD_READ_N(bits) \
456 static inline int nbd_read##bits(QIOChannel *ioc, \
457 uint##bits##_t *val, \
458 const char *desc, Error **errp) \
459 { \
460 int ret = nbd_read(ioc, val, sizeof(*val), desc, errp); \
461 if (ret < 0) { \
462 return ret; \
463 } \
464 *val = be##bits##_to_cpu(*val); \
465 return 0; \
466 }
467
468 DEF_NBD_READ_N(16) /* Defines nbd_read16(). */
469 DEF_NBD_READ_N(32) /* Defines nbd_read32(). */
470 DEF_NBD_READ_N(64) /* Defines nbd_read64(). */
471
472 #undef DEF_NBD_READ_N
473
nbd_reply_is_simple(NBDReply * reply)474 static inline bool nbd_reply_is_simple(NBDReply *reply)
475 {
476 return reply->magic == NBD_SIMPLE_REPLY_MAGIC;
477 }
478
nbd_reply_is_structured(NBDReply * reply)479 static inline bool nbd_reply_is_structured(NBDReply *reply)
480 {
481 return reply->magic == NBD_STRUCTURED_REPLY_MAGIC;
482 }
483
484 const char *nbd_reply_type_lookup(uint16_t type);
485 const char *nbd_opt_lookup(uint32_t opt);
486 const char *nbd_rep_lookup(uint32_t rep);
487 const char *nbd_info_lookup(uint16_t info);
488 const char *nbd_cmd_lookup(uint16_t info);
489 const char *nbd_err_lookup(int err);
490 const char *nbd_mode_lookup(NBDMode mode);
491
492 /* nbd/client-connection.c */
493 void nbd_client_connection_enable_retry(NBDClientConnection *conn);
494
495 NBDClientConnection *nbd_client_connection_new(const SocketAddress *saddr,
496 bool do_negotiation,
497 const char *export_name,
498 const char *x_dirty_bitmap,
499 QCryptoTLSCreds *tlscreds,
500 const char *tlshostname);
501 void nbd_client_connection_release(NBDClientConnection *conn);
502
503 QIOChannel *coroutine_fn
504 nbd_co_establish_connection(NBDClientConnection *conn, NBDExportInfo *info,
505 bool blocking, Error **errp);
506
507 void nbd_co_establish_connection_cancel(NBDClientConnection *conn);
508
509 #endif
510