summaryrefslogtreecommitdiffstats
path: root/include/linux/ceph/messenger.h
blob: 2eaaabbe98cb64d3f64a698a6f527e244649ca4e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __FS_CEPH_MESSENGER_H
#define __FS_CEPH_MESSENGER_H

#include <linux/bvec.h>
#include <linux/crypto.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/net.h>
#include <linux/radix-tree.h>
#include <linux/uio.h>
#include <linux/workqueue.h>
#include <net/net_namespace.h>

#include <linux/ceph/types.h>
#include <linux/ceph/buffer.h>

struct ceph_msg;
struct ceph_connection;
struct ceph_msg_data_cursor;

/*
 * Ceph defines these callbacks for handling connection events.
 */
struct ceph_connection_operations {
	struct ceph_connection *(*get)(struct ceph_connection *);
	void (*put)(struct ceph_connection *);

	/* handle an incoming message. */
	void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);

	/* authorize an outgoing connection */
	struct ceph_auth_handshake *(*get_authorizer) (
				struct ceph_connection *con,
			       int *proto, int force_new);
	int (*add_authorizer_challenge)(struct ceph_connection *con,
					void *challenge_buf,
					int challenge_buf_len);
	int (*verify_authorizer_reply) (struct ceph_connection *con);
	int (*invalidate_authorizer)(struct ceph_connection *con);

	/* there was some error on the socket (disconnect, whatever) */
	void (*fault) (struct ceph_connection *con);

	/* a remote host as terminated a message exchange session, and messages
	 * we sent (or they tried to send us) may be lost. */
	void (*peer_reset) (struct ceph_connection *con);

	struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
					struct ceph_msg_header *hdr,
					int *skip);

	void (*reencode_message) (struct ceph_msg *msg);

	int (*sign_message) (struct ceph_msg *msg);
	int (*check_message_signature) (struct ceph_msg *msg);

	/* msgr2 authentication exchange */
	int (*get_auth_request)(struct ceph_connection *con,
				void *buf, int *buf_len,
				void **authorizer, int *authorizer_len);
	int (*handle_auth_reply_more)(struct ceph_connection *con,
				      void *reply, int reply_len,
				      void *buf, int *buf_len,
				      void **authorizer, int *authorizer_len);
	int (*handle_auth_done)(struct ceph_connection *con,
				u64 global_id, void *reply, int reply_len,
				u8 *session_key, int *session_key_len,
				u8 *con_secret, int *con_secret_len);
	int (*handle_auth_bad_method)(struct ceph_connection *con,
				      int used_proto, int result,
				      const int *allowed_protos, int proto_cnt,
				      const int *allowed_modes, int mode_cnt);

	/**
	 * sparse_read: read sparse data
	 * @con: connection we're reading from
	 * @cursor: data cursor for reading extents
	 * @buf: optional buffer to read into
	 *
	 * This should be called more than once, each time setting up to
	 * receive an extent into the current cursor position, and zeroing
	 * the holes between them.
	 *
	 * Returns amount of data to be read (in bytes), 0 if reading is
	 * complete, or -errno if there was an error.
	 *
	 * If @buf is set on a >0 return, then the data should be read into
	 * the provided buffer. Otherwise, it should be read into the cursor.
	 *
	 * The sparse read operation is expected to initialize the cursor
	 * with a length covering up to the end of the last extent.
	 */
	int (*sparse_read)(struct ceph_connection *con,
			   struct ceph_msg_data_cursor *cursor,
			   char **buf);

};

/* use format string %s%lld */
#define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)

struct ceph_messenger {
	struct ceph_entity_inst inst;    /* my name+address */
	struct ceph_entity_addr my_enc_addr;

	atomic_t stopping;
	possible_net_t net;

	/*
	 * the global_seq counts connections i (attempt to) initiate
	 * in order to disambiguate certain connect race conditions.
	 */
	u32 global_seq;
	spinlock_t global_seq_lock;
};

enum ceph_msg_data_type {
	CEPH_MSG_DATA_NONE,	/* message contains no data payload */
	CEPH_MSG_DATA_PAGES,	/* data source/destination is a page array */
	CEPH_MSG_DATA_PAGELIST,	/* data source/destination is a pagelist */
#ifdef CONFIG_BLOCK
	CEPH_MSG_DATA_BIO,	/* data source/destination is a bio list */
#endif /* CONFIG_BLOCK */
	CEPH_MSG_DATA_BVECS,	/* data source/destination is a bio_vec array */
	CEPH_MSG_DATA_ITER,	/* data source/destination is an iov_iter */
};

#ifdef CONFIG_BLOCK

struct ceph_bio_iter {
	struct bio *bio;
	struct bvec_iter iter;
};

#define __ceph_bio_iter_advance_step(it, n, STEP) do {			      \
	unsigned int __n = (n), __cur_n;				      \
									      \
	while (__n) {							      \
		BUG_ON(!(it)->iter.bi_size);				      \
		__cur_n = min((it)->iter.bi_size, __n);			      \
		(void)(STEP);						      \
		bio_advance_iter((it)->bio, &(it)->iter, __cur_n);	      \
		if (!(it)->iter.bi_size && (it)->bio->bi_next) {	      \
			dout("__ceph_bio_iter_advance_step next bio\n");      \
			(it)->bio = (it)->bio->bi_next;			      \
			(it)->iter = (it)->bio->bi_iter;		      \
		}							      \
		__n -= __cur_n;						      \
	}								      \
} while (0)

/*
 * Advance @it by @n bytes.
 */
#define ceph_bio_iter_advance(it, n)					      \
	__ceph_bio_iter_advance_step(it, n, 0)

/*
 * Advance @it by @n bytes, executing BVEC_STEP for each bio_vec.
 */
#define ceph_bio_iter_advance_step(it, n, BVEC_STEP)			      \
	__ceph_bio_iter_advance_step(it, n, ({				      \
		struct bio_vec bv;					      \
		struct bvec_iter __cur_iter;				      \
									      \
		__cur_iter = (it)->iter;				      \
		__cur_iter.bi_size = __cur_n;				      \
		__bio_for_each_segment(bv, (it)->bio, __cur_iter, __cur_iter) \
			(void)(BVEC_STEP);				      \
	}))

#endif /* CONFIG_BLOCK */

struct ceph_bvec_iter {
	struct bio_vec *bvecs;
	struct bvec_iter iter;
};

#define __ceph_bvec_iter_advance_step(it, n, STEP) do {			      \
	BUG_ON((n) > (it)->iter.bi_size);				      \
	(void)(STEP);							      \
	bvec_iter_advance((it)->bvecs, &(it)->iter, (n));		      \
} while (0)

/*
 * Advance @it by @n bytes.
 */
#define ceph_bvec_iter_advance(it, n)					      \
	__ceph_bvec_iter_advance_step(it, n, 0)

/*
 * Advance @it by @n bytes, executing BVEC_STEP for each bio_vec.
 */
#define ceph_bvec_iter_advance_step(it, n, BVEC_STEP)			      \
	__ceph_bvec_iter_advance_step(it, n, ({				      \
		struct bio_vec bv;					      \
		struct bvec_iter __cur_iter;				      \
									      \
		__cur_iter = (it)->iter;				      \
		__cur_iter.bi_size = (n);				      \
		for_each_bvec(bv, (it)->bvecs, __cur_iter, __cur_iter)	      \
			(void)(BVEC_STEP);				      \
	}))

#define ceph_bvec_iter_shorten(it, n) do {				      \
	BUG_ON((n) > (it)->iter.bi_size);				      \
	(it)->iter.bi_size = (n);					      \
} while (0)

struct ceph_msg_data {
	enum ceph_msg_data_type		type;
	union {
#ifdef CONFIG_BLOCK
		struct {
			struct ceph_bio_iter	bio_pos;
			u32			bio_length;
		};
#endif /* CONFIG_BLOCK */
		struct ceph_bvec_iter	bvec_pos;
		struct {
			struct page	**pages;
			size_t		length;		/* total # bytes */
			unsigned int	alignment;	/* first page */
			bool		own_pages;
		};
		struct ceph_pagelist	*pagelist;
		struct iov_iter		iter;
	};
};

struct ceph_msg_data_cursor {
	size_t			total_resid;	/* across all data items */

	struct ceph_msg_data	*data;		/* current data item */
	size_t			resid;		/* bytes not yet consumed */
	int			sr_resid;	/* residual sparse_read len */
	bool			need_crc;	/* crc update needed */
	union {
#ifdef CONFIG_BLOCK
		struct ceph_bio_iter	bio_iter;
#endif /* CONFIG_BLOCK */
		struct bvec_iter	bvec_iter;
		struct {				/* pages */
			unsigned int	page_offset;	/* offset in page */
			unsigned short	page_index;	/* index in array */
			unsigned short	page_count;	/* pages in array */
		};
		struct {				/* pagelist */
			struct page	*page;		/* page from list */
			size_t		offset;		/* bytes from list */
		};
		struct {
			struct iov_iter		iov_iter;
			unsigned int		lastlen;
		};
	};
};

/*
 * a single message.  it contains a header (src, dest, message type, etc.),
 * footer (crc values, mainly), a "front" message body, and possibly a
 * data payload (stored in some number of pages).
 */
struct ceph_msg {
	struct ceph_msg_header hdr;	/* header */
	union {
		struct ceph_msg_footer footer;		/* footer */
		struct ceph_msg_footer_old old_footer;	/* old format footer */
	};
	struct kvec front;              /* unaligned blobs of message */
	struct ceph_buffer *middle;

	size_t				data_length;
	struct ceph_msg_data		*data;
	int				num_data_items;
	int				max_data_items;
	struct ceph_msg_data_cursor	cursor;

	struct ceph_connection *con;
	struct list_head list_head;	/* links for connection lists */

	struct kref kref;
	bool more_to_follow;
	bool needs_out_seq;
	bool sparse_read;
	int front_alloc_len;

	struct ceph_msgpool *pool;
};

/*
 * connection states
 */
#define CEPH_CON_S_CLOSED		1
#define CEPH_CON_S_PREOPEN		2
#define CEPH_CON_S_V1_BANNER		3
#define CEPH_CON_S_V1_CONNECT_MSG	4
#define CEPH_CON_S_V2_BANNER_PREFIX	5
#define CEPH_CON_S_V2_BANNER_PAYLOAD	6
#define CEPH_CON_S_V2_HELLO		7
#define CEPH_CON_S_V2_AUTH		8
#define CEPH_CON_S_V2_AUTH_SIGNATURE	9
#define CEPH_CON_S_V2_SESSION_CONNECT	10
#define CEPH_CON_S_V2_SESSION_RECONNECT	11
#define CEPH_CON_S_OPEN			12
#define CEPH_CON_S_STANDBY		13

/*
 * ceph_connection flag bits
 */
#define CEPH_CON_F_LOSSYTX		0  /* we can close channel or drop
					      messages on errors */
#define CEPH_CON_F_KEEPALIVE_PENDING	1  /* we need to send a keepalive */
#define CEPH_CON_F_WRITE_PENDING	2  /* we have data ready to send */
#define CEPH_CON_F_SOCK_CLOSED		3  /* socket state changed to closed */
#define CEPH_CON_F_BACKOFF		4  /* need to retry queuing delayed
					      work */

/* ceph connection fault delay defaults, for exponential backoff */
#define BASE_DELAY_INTERVAL	(HZ / 4)
#define MAX_DELAY_INTERVAL	(15 * HZ)

struct ceph_connection_v1_info {
	struct kvec out_kvec[8],         /* sending header/footer data */
		*out_kvec_cur;
	int out_kvec_left;   /* kvec's left in out_kvec */
	int out_skip;        /* skip this many bytes */
	int out_kvec_bytes;  /* total bytes left */
	bool out_more;       /* there is more data after the kvecs */
	bool out_msg_done;

	struct ceph_auth_handshake *auth;
	int auth_retry;       /* true if we need a newer authorizer */

	/* connection negotiation temps */
	u8 in_banner[CEPH_BANNER_MAX_LEN];
	struct ceph_entity_addr actual_peer_addr;
	struct ceph_entity_addr peer_addr_for_me;
	struct ceph_msg_connect out_connect;
	struct ceph_msg_connect_reply in_reply;

	int in_base_pos;     /* bytes read */

	/* sparse reads */
	struct kvec in_sr_kvec; /* current location to receive into */
	u64 in_sr_len;		/* amount of data in this extent */

	/* message in temps */
	u8 in_tag;           /* protocol control byte */
	struct ceph_msg_header in_hdr;
	__le64 in_temp_ack;  /* for reading an ack */

	/* message out temps */
	struct ceph_msg_header out_hdr;
	__le64 out_temp_ack;  /* for writing an ack */
	struct ceph_timespec out_temp_keepalive2;  /* for writing keepalive2
						      stamp */

	u32 connect_seq;      /* identify the most recent connection
				 attempt for this session */
	u32 peer_global_seq;  /* peer's global seq for this connection */
};

#define CEPH_CRC_LEN			4
#define CEPH_GCM_KEY_LEN		16
#define CEPH_GCM_IV_LEN			sizeof(struct ceph_gcm_nonce)
#define CEPH_GCM_BLOCK_LEN		16
#define CEPH_GCM_TAG_LEN		16

#define CEPH_PREAMBLE_LEN		32
#define CEPH_PREAMBLE_INLINE_LEN	48
#define CEPH_PREAMBLE_PLAIN_LEN		CEPH_PREAMBLE_LEN
#define CEPH_PREAMBLE_SECURE_LEN	(CEPH_PREAMBLE_LEN +		\
					 CEPH_PREAMBLE_INLINE_LEN +	\
					 CEPH_GCM_TAG_LEN)
#define CEPH_EPILOGUE_PLAIN_LEN		(1 + 3 * CEPH_CRC_LEN)
#define CEPH_EPILOGUE_SECURE_LEN	(CEPH_GCM_BLOCK_LEN + CEPH_GCM_TAG_LEN)

#define CEPH_FRAME_MAX_SEGMENT_COUNT	4

struct ceph_frame_desc {
	int fd_tag;  /* FRAME_TAG_* */
	int fd_seg_cnt;
	int fd_lens[CEPH_FRAME_MAX_SEGMENT_COUNT];  /* logical */
	int fd_aligns[CEPH_FRAME_MAX_SEGMENT_COUNT];
};

struct ceph_gcm_nonce {
	__le32 fixed;
	__le64 counter __packed;
};

struct ceph_connection_v2_info {
	struct iov_iter in_iter;
	struct kvec in_kvecs[5];  /* recvmsg */
	struct bio_vec in_bvec;  /* recvmsg (in_cursor) */
	int in_kvec_cnt;
	int in_state;  /* IN_S_* */

	struct iov_iter out_iter;
	struct kvec out_kvecs[8];  /* sendmsg */
	struct bio_vec out_bvec;  /* sendpage (out_cursor, out_zero),
				     sendmsg (out_enc_pages) */
	int out_kvec_cnt;
	int out_state;  /* OUT_S_* */

	int out_zero;  /* # of zero bytes to send */
	bool out_iter_sendpage;  /* use sendpage if possible */

	struct ceph_frame_desc in_desc;
	struct ceph_msg_data_cursor in_cursor;
	struct ceph_msg_data_cursor out_cursor;

	struct crypto_shash *hmac_tfm;  /* post-auth signature */
	struct crypto_aead *gcm_tfm;  /* on-wire encryption */
	struct aead_request *gcm_req;
	struct crypto_wait gcm_wait;
	struct ceph_gcm_nonce in_gcm_nonce;
	struct ceph_gcm_nonce out_gcm_nonce;

	struct page **in_enc_pages;
	int in_enc_page_cnt;
	int in_enc_resid;
	int in_enc_i;
	struct page **out_enc_pages;
	int out_enc_page_cnt;
	int out_enc_resid;
	int out_enc_i;

	int con_mode;  /* CEPH_CON_MODE_* */

	void *conn_bufs[16];
	int conn_buf_cnt;
	int data_len_remain;

	struct kvec in_sign_kvecs[8];
	struct kvec out_sign_kvecs[8];
	int in_sign_kvec_cnt;
	int out_sign_kvec_cnt;

	u64 client_cookie;
	u64 server_cookie;
	u64 global_seq;
	u64 connect_seq;
	u64 peer_global_seq;

	u8 in_buf[CEPH_PREAMBLE_SECURE_LEN];
	u8 out_buf[CEPH_PREAMBLE_SECURE_LEN];
	struct {
		u8 late_status;  /* FRAME_LATE_STATUS_* */
		union {
			struct {
				u32 front_crc;
				u32 middle_crc;
				u32 data_crc;
			} __packed;
			u8 pad[CEPH_GCM_BLOCK_LEN - 1];
		};
	} out_epil;
};

/*
 * A single connection with another host.
 *
 * We maintain a queue of outgoing messages, and some session state to
 * ensure that we can preserve the lossless, ordered delivery of
 * messages in the case of a TCP disconnect.
 */
struct ceph_connection {
	void *private;

	const struct ceph_connection_operations *ops;

	struct ceph_messenger *msgr;

	int state;  /* CEPH_CON_S_* */
	atomic_t sock_state;
	struct socket *sock;

	unsigned long flags;  /* CEPH_CON_F_* */
	const char *error_msg;  /* error message, if any */

	struct ceph_entity_name peer_name; /* peer name */
	struct ceph_entity_addr peer_addr; /* peer address */
	u64 peer_features;

	struct mutex mutex;

	/* out queue */
	struct list_head out_queue;
	struct list_head out_sent;   /* sending or sent but unacked */
	u64 out_seq;		     /* last message queued for send */

	u64 in_seq, in_seq_acked;  /* last message received, acked */

	struct ceph_msg *in_msg;
	struct ceph_msg *out_msg;        /* sending message (== tail of
					    out_sent) */

	struct page *bounce_page;
	u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */

	struct timespec64 last_keepalive_ack; /* keepalive2 ack stamp */

	struct delayed_work work;	    /* send|recv work */
	unsigned long       delay;          /* current delay interval */

	union {
		struct ceph_connection_v1_info v1;
		struct ceph_connection_v2_info v2;
	};
};

extern struct page *ceph_zero_page;

void ceph_con_flag_clear(struct ceph_connection *con, unsigned long con_flag);
void ceph_con_flag_set(struct ceph_connection *con, unsigned long con_flag);
bool ceph_con_flag_test(struct ceph_connection *con, unsigned long con_flag);
bool ceph_con_flag_test_and_clear(struct ceph_connection *con,
				  unsigned long con_flag);
bool ceph_con_flag_test_and_set(struct ceph_connection *con,
				unsigned long con_flag);

void ceph_encode_my_addr(struct ceph_messenger *msgr);

int ceph_tcp_connect(struct ceph_connection *con);
int ceph_con_close_socket(struct ceph_connection *con);
void ceph_con_reset_session(struct ceph_connection *con);

u32 ceph_get_global_seq(struct ceph_messenger *msgr, u32 gt);
void ceph_con_discard_sent(struct ceph_connection *con, u64 ack_seq);
void ceph_con_discard_requeued(struct ceph_connection *con, u64 reconnect_seq);

void ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor,
			       struct ceph_msg *msg, size_t length);
struct page *ceph_msg_data_next(struct ceph_msg_data_cursor *cursor,
				size_t *page_offset, size_t *length);
void ceph_msg_data_advance(struct ceph_msg_data_cursor *cursor, size_t bytes);

u32 ceph_crc32c_page(u32 crc, struct page *page, unsigned int page_offset,
		     unsigned int length);

bool ceph_addr_is_blank(const struct ceph_entity_addr *addr);
int ceph_addr_port(const struct ceph_entity_addr *addr);
void ceph_addr_set_port(struct ceph_entity_addr *addr, int p);

void ceph_con_process_message(struct ceph_connection *con);
int ceph_con_in_msg_alloc(struct ceph_connection *con,
			  struct ceph_msg_header *hdr, int *skip);
void ceph_con_get_out_msg(struct ceph_connection *con);

/* messenger_v1.c */
int ceph_con_v1_try_read(struct ceph_connection *con);
int ceph_con_v1_try_write(struct ceph_connection *con);
void ceph_con_v1_revoke(struct ceph_connection *con);
void ceph_con_v1_revoke_incoming(struct ceph_connection *con);
bool ceph_con_v1_opened(struct ceph_connection *con);
void ceph_con_v1_reset_session(struct ceph_connection *con);
void ceph_con_v1_reset_protocol(struct ceph_connection *con);

/* messenger_v2.c */
int ceph_con_v2_try_read(struct ceph_connection *con);
int ceph_con_v2_try_write(struct ceph_connection *con);
void ceph_con_v2_revoke(struct ceph_connection *con);
void ceph_con_v2_revoke_incoming(struct ceph_connection *con);
bool ceph_con_v2_opened(struct ceph_connection *con);
void ceph_con_v2_reset_session(struct ceph_connection *con);
void ceph_con_v2_reset_protocol(struct ceph_connection *con);


extern const char *ceph_pr_addr(const struct ceph_entity_addr *addr);

extern int ceph_parse_ips(const char *c, const char *end,
			  struct ceph_entity_addr *addr,
			  int max_count, int *count, char delim);

extern int ceph_msgr_init(void);
extern void ceph_msgr_exit(void);
extern void ceph_msgr_flush(void);

extern void ceph_messenger_init(struct ceph_messenger *msgr,
				struct ceph_entity_addr *myaddr);
extern void ceph_messenger_fini(struct ceph_messenger *msgr);
extern void ceph_messenger_reset_nonce(struct ceph_messenger *msgr);

extern void ceph_con_init(struct ceph_connection *con, void *private,
			const struct ceph_connection_operations *ops,
			struct ceph_messenger *msgr);
extern void ceph_con_open(struct ceph_connection *con,
			  __u8 entity_type, __u64 entity_num,
			  struct ceph_entity_addr *addr);
extern bool ceph_con_opened(struct ceph_connection *con);
extern void ceph_con_close(struct ceph_connection *con);
extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);

extern void ceph_msg_revoke(struct ceph_msg *msg);
extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);

extern void ceph_con_keepalive(struct ceph_connection *con);
extern bool ceph_con_keepalive_expired(struct ceph_connection *con,
				       unsigned long interval);

void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages,
			     size_t length, size_t alignment, bool own_pages);
extern void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
				struct ceph_pagelist *pagelist);
#ifdef CONFIG_BLOCK
void ceph_msg_data_add_bio(struct ceph_msg *msg, struct ceph_bio_iter *bio_pos,
			   u32 length);
#endif /* CONFIG_BLOCK */
void ceph_msg_data_add_bvecs(struct ceph_msg *msg,
			     struct ceph_bvec_iter *bvec_pos);
void ceph_msg_data_add_iter(struct ceph_msg *msg,
			    struct iov_iter *iter);

struct ceph_msg *ceph_msg_new2(int type, int front_len, int max_data_items,
			       gfp_t flags, bool can_fail);
extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
				     bool can_fail);

extern struct ceph_msg *ceph_msg_get(struct ceph_msg *msg);
extern void ceph_msg_put(struct ceph_msg *msg);

extern void ceph_msg_dump(struct ceph_msg *msg);

#endif