1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __FS_CEPH_MESSENGER_H
3 #define __FS_CEPH_MESSENGER_H
4 
5 #include <linux/bvec.h>
6 #include <linux/kref.h>
7 #include <linux/mutex.h>
8 #include <linux/net.h>
9 #include <linux/radix-tree.h>
10 #include <linux/uio.h>
11 #include <linux/workqueue.h>
12 #include <net/net_namespace.h>
13 
14 #include <linux/ceph/types.h>
15 #include <linux/ceph/buffer.h>
16 
17 struct ceph_msg;
18 struct ceph_connection;
19 
20 /*
21  * Ceph defines these callbacks for handling connection events.
22  */
23 struct ceph_connection_operations {
24 	struct ceph_connection *(*get)(struct ceph_connection *);
25 	void (*put)(struct ceph_connection *);
26 
27 	/* handle an incoming message. */
28 	void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
29 
30 	/* authorize an outgoing connection */
31 	struct ceph_auth_handshake *(*get_authorizer) (
32 				struct ceph_connection *con,
33 			       int *proto, int force_new);
34 	int (*add_authorizer_challenge)(struct ceph_connection *con,
35 					void *challenge_buf,
36 					int challenge_buf_len);
37 	int (*verify_authorizer_reply) (struct ceph_connection *con);
38 	int (*invalidate_authorizer)(struct ceph_connection *con);
39 
40 	/* there was some error on the socket (disconnect, whatever) */
41 	void (*fault) (struct ceph_connection *con);
42 
43 	/* a remote host as terminated a message exchange session, and messages
44 	 * we sent (or they tried to send us) may be lost. */
45 	void (*peer_reset) (struct ceph_connection *con);
46 
47 	struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
48 					struct ceph_msg_header *hdr,
49 					int *skip);
50 
51 	void (*reencode_message) (struct ceph_msg *msg);
52 
53 	int (*sign_message) (struct ceph_msg *msg);
54 	int (*check_message_signature) (struct ceph_msg *msg);
55 };
56 
57 /* use format string %s%lld */
58 #define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
59 
60 struct ceph_messenger {
61 	struct ceph_entity_inst inst;    /* my name+address */
62 	struct ceph_entity_addr my_enc_addr;
63 
64 	atomic_t stopping;
65 	possible_net_t net;
66 
67 	/*
68 	 * the global_seq counts connections i (attempt to) initiate
69 	 * in order to disambiguate certain connect race conditions.
70 	 */
71 	u32 global_seq;
72 	spinlock_t global_seq_lock;
73 };
74 
75 enum ceph_msg_data_type {
76 	CEPH_MSG_DATA_NONE,	/* message contains no data payload */
77 	CEPH_MSG_DATA_PAGES,	/* data source/destination is a page array */
78 	CEPH_MSG_DATA_PAGELIST,	/* data source/destination is a pagelist */
79 #ifdef CONFIG_BLOCK
80 	CEPH_MSG_DATA_BIO,	/* data source/destination is a bio list */
81 #endif /* CONFIG_BLOCK */
82 	CEPH_MSG_DATA_BVECS,	/* data source/destination is a bio_vec array */
83 };
84 
85 #ifdef CONFIG_BLOCK
86 
87 struct ceph_bio_iter {
88 	struct bio *bio;
89 	struct bvec_iter iter;
90 };
91 
92 #define __ceph_bio_iter_advance_step(it, n, STEP) do {			      \
93 	unsigned int __n = (n), __cur_n;				      \
94 									      \
95 	while (__n) {							      \
96 		BUG_ON(!(it)->iter.bi_size);				      \
97 		__cur_n = min((it)->iter.bi_size, __n);			      \
98 		(void)(STEP);						      \
99 		bio_advance_iter((it)->bio, &(it)->iter, __cur_n);	      \
100 		if (!(it)->iter.bi_size && (it)->bio->bi_next) {	      \
101 			dout("__ceph_bio_iter_advance_step next bio\n");      \
102 			(it)->bio = (it)->bio->bi_next;			      \
103 			(it)->iter = (it)->bio->bi_iter;		      \
104 		}							      \
105 		__n -= __cur_n;						      \
106 	}								      \
107 } while (0)
108 
109 /*
110  * Advance @it by @n bytes.
111  */
112 #define ceph_bio_iter_advance(it, n)					      \
113 	__ceph_bio_iter_advance_step(it, n, 0)
114 
115 /*
116  * Advance @it by @n bytes, executing BVEC_STEP for each bio_vec.
117  */
118 #define ceph_bio_iter_advance_step(it, n, BVEC_STEP)			      \
119 	__ceph_bio_iter_advance_step(it, n, ({				      \
120 		struct bio_vec bv;					      \
121 		struct bvec_iter __cur_iter;				      \
122 									      \
123 		__cur_iter = (it)->iter;				      \
124 		__cur_iter.bi_size = __cur_n;				      \
125 		__bio_for_each_segment(bv, (it)->bio, __cur_iter, __cur_iter) \
126 			(void)(BVEC_STEP);				      \
127 	}))
128 
129 #endif /* CONFIG_BLOCK */
130 
131 struct ceph_bvec_iter {
132 	struct bio_vec *bvecs;
133 	struct bvec_iter iter;
134 };
135 
136 #define __ceph_bvec_iter_advance_step(it, n, STEP) do {			      \
137 	BUG_ON((n) > (it)->iter.bi_size);				      \
138 	(void)(STEP);							      \
139 	bvec_iter_advance((it)->bvecs, &(it)->iter, (n));		      \
140 } while (0)
141 
142 /*
143  * Advance @it by @n bytes.
144  */
145 #define ceph_bvec_iter_advance(it, n)					      \
146 	__ceph_bvec_iter_advance_step(it, n, 0)
147 
148 /*
149  * Advance @it by @n bytes, executing BVEC_STEP for each bio_vec.
150  */
151 #define ceph_bvec_iter_advance_step(it, n, BVEC_STEP)			      \
152 	__ceph_bvec_iter_advance_step(it, n, ({				      \
153 		struct bio_vec bv;					      \
154 		struct bvec_iter __cur_iter;				      \
155 									      \
156 		__cur_iter = (it)->iter;				      \
157 		__cur_iter.bi_size = (n);				      \
158 		for_each_bvec(bv, (it)->bvecs, __cur_iter, __cur_iter)	      \
159 			(void)(BVEC_STEP);				      \
160 	}))
161 
162 #define ceph_bvec_iter_shorten(it, n) do {				      \
163 	BUG_ON((n) > (it)->iter.bi_size);				      \
164 	(it)->iter.bi_size = (n);					      \
165 } while (0)
166 
167 struct ceph_msg_data {
168 	enum ceph_msg_data_type		type;
169 	union {
170 #ifdef CONFIG_BLOCK
171 		struct {
172 			struct ceph_bio_iter	bio_pos;
173 			u32			bio_length;
174 		};
175 #endif /* CONFIG_BLOCK */
176 		struct ceph_bvec_iter	bvec_pos;
177 		struct {
178 			struct page	**pages;
179 			size_t		length;		/* total # bytes */
180 			unsigned int	alignment;	/* first page */
181 			bool		own_pages;
182 		};
183 		struct ceph_pagelist	*pagelist;
184 	};
185 };
186 
187 struct ceph_msg_data_cursor {
188 	size_t			total_resid;	/* across all data items */
189 
190 	struct ceph_msg_data	*data;		/* current data item */
191 	size_t			resid;		/* bytes not yet consumed */
192 	bool			last_piece;	/* current is last piece */
193 	bool			need_crc;	/* crc update needed */
194 	union {
195 #ifdef CONFIG_BLOCK
196 		struct ceph_bio_iter	bio_iter;
197 #endif /* CONFIG_BLOCK */
198 		struct bvec_iter	bvec_iter;
199 		struct {				/* pages */
200 			unsigned int	page_offset;	/* offset in page */
201 			unsigned short	page_index;	/* index in array */
202 			unsigned short	page_count;	/* pages in array */
203 		};
204 		struct {				/* pagelist */
205 			struct page	*page;		/* page from list */
206 			size_t		offset;		/* bytes from list */
207 		};
208 	};
209 };
210 
211 /*
212  * a single message.  it contains a header (src, dest, message type, etc.),
213  * footer (crc values, mainly), a "front" message body, and possibly a
214  * data payload (stored in some number of pages).
215  */
216 struct ceph_msg {
217 	struct ceph_msg_header hdr;	/* header */
218 	union {
219 		struct ceph_msg_footer footer;		/* footer */
220 		struct ceph_msg_footer_old old_footer;	/* old format footer */
221 	};
222 	struct kvec front;              /* unaligned blobs of message */
223 	struct ceph_buffer *middle;
224 
225 	size_t				data_length;
226 	struct ceph_msg_data		*data;
227 	int				num_data_items;
228 	int				max_data_items;
229 	struct ceph_msg_data_cursor	cursor;
230 
231 	struct ceph_connection *con;
232 	struct list_head list_head;	/* links for connection lists */
233 
234 	struct kref kref;
235 	bool more_to_follow;
236 	bool needs_out_seq;
237 	int front_alloc_len;
238 	unsigned long ack_stamp;        /* tx: when we were acked */
239 
240 	struct ceph_msgpool *pool;
241 };
242 
243 /* ceph connection fault delay defaults, for exponential backoff */
244 #define BASE_DELAY_INTERVAL	(HZ/2)
245 #define MAX_DELAY_INTERVAL	(5 * 60 * HZ)
246 
247 /*
248  * A single connection with another host.
249  *
250  * We maintain a queue of outgoing messages, and some session state to
251  * ensure that we can preserve the lossless, ordered delivery of
252  * messages in the case of a TCP disconnect.
253  */
254 struct ceph_connection {
255 	void *private;
256 
257 	const struct ceph_connection_operations *ops;
258 
259 	struct ceph_messenger *msgr;
260 
261 	atomic_t sock_state;
262 	struct socket *sock;
263 	struct ceph_entity_addr peer_addr; /* peer address */
264 	struct ceph_entity_addr peer_addr_for_me;
265 
266 	unsigned long flags;
267 	unsigned long state;
268 	const char *error_msg;  /* error message, if any */
269 
270 	struct ceph_entity_name peer_name; /* peer name */
271 
272 	u64 peer_features;
273 	u32 connect_seq;      /* identify the most recent connection
274 				 attempt for this connection, client */
275 	u32 peer_global_seq;  /* peer's global seq for this connection */
276 
277 	struct ceph_auth_handshake *auth;
278 	int auth_retry;       /* true if we need a newer authorizer */
279 
280 	struct mutex mutex;
281 
282 	/* out queue */
283 	struct list_head out_queue;
284 	struct list_head out_sent;   /* sending or sent but unacked */
285 	u64 out_seq;		     /* last message queued for send */
286 
287 	u64 in_seq, in_seq_acked;  /* last message received, acked */
288 
289 	/* connection negotiation temps */
290 	char in_banner[CEPH_BANNER_MAX_LEN];
291 	struct ceph_msg_connect out_connect;
292 	struct ceph_msg_connect_reply in_reply;
293 	struct ceph_entity_addr actual_peer_addr;
294 
295 	/* message out temps */
296 	struct ceph_msg_header out_hdr;
297 	struct ceph_msg *out_msg;        /* sending message (== tail of
298 					    out_sent) */
299 	bool out_msg_done;
300 
301 	struct kvec out_kvec[8],         /* sending header/footer data */
302 		*out_kvec_cur;
303 	int out_kvec_left;   /* kvec's left in out_kvec */
304 	int out_skip;        /* skip this many bytes */
305 	int out_kvec_bytes;  /* total bytes left */
306 	int out_more;        /* there is more data after the kvecs */
307 	__le64 out_temp_ack; /* for writing an ack */
308 	struct ceph_timespec out_temp_keepalive2; /* for writing keepalive2
309 						     stamp */
310 
311 	/* message in temps */
312 	struct ceph_msg_header in_hdr;
313 	struct ceph_msg *in_msg;
314 	u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
315 
316 	char in_tag;         /* protocol control byte */
317 	int in_base_pos;     /* bytes read */
318 	__le64 in_temp_ack;  /* for reading an ack */
319 
320 	struct timespec64 last_keepalive_ack; /* keepalive2 ack stamp */
321 
322 	struct delayed_work work;	    /* send|recv work */
323 	unsigned long       delay;          /* current delay interval */
324 };
325 
326 
327 extern const char *ceph_pr_addr(const struct ceph_entity_addr *addr);
328 
329 extern int ceph_parse_ips(const char *c, const char *end,
330 			  struct ceph_entity_addr *addr,
331 			  int max_count, int *count);
332 
333 
334 extern int ceph_msgr_init(void);
335 extern void ceph_msgr_exit(void);
336 extern void ceph_msgr_flush(void);
337 
338 extern void ceph_messenger_init(struct ceph_messenger *msgr,
339 				struct ceph_entity_addr *myaddr);
340 extern void ceph_messenger_fini(struct ceph_messenger *msgr);
341 extern void ceph_messenger_reset_nonce(struct ceph_messenger *msgr);
342 
343 extern void ceph_con_init(struct ceph_connection *con, void *private,
344 			const struct ceph_connection_operations *ops,
345 			struct ceph_messenger *msgr);
346 extern void ceph_con_open(struct ceph_connection *con,
347 			  __u8 entity_type, __u64 entity_num,
348 			  struct ceph_entity_addr *addr);
349 extern bool ceph_con_opened(struct ceph_connection *con);
350 extern void ceph_con_close(struct ceph_connection *con);
351 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
352 
353 extern void ceph_msg_revoke(struct ceph_msg *msg);
354 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
355 
356 extern void ceph_con_keepalive(struct ceph_connection *con);
357 extern bool ceph_con_keepalive_expired(struct ceph_connection *con,
358 				       unsigned long interval);
359 
360 void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages,
361 			     size_t length, size_t alignment, bool own_pages);
362 extern void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
363 				struct ceph_pagelist *pagelist);
364 #ifdef CONFIG_BLOCK
365 void ceph_msg_data_add_bio(struct ceph_msg *msg, struct ceph_bio_iter *bio_pos,
366 			   u32 length);
367 #endif /* CONFIG_BLOCK */
368 void ceph_msg_data_add_bvecs(struct ceph_msg *msg,
369 			     struct ceph_bvec_iter *bvec_pos);
370 
371 struct ceph_msg *ceph_msg_new2(int type, int front_len, int max_data_items,
372 			       gfp_t flags, bool can_fail);
373 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
374 				     bool can_fail);
375 
376 extern struct ceph_msg *ceph_msg_get(struct ceph_msg *msg);
377 extern void ceph_msg_put(struct ceph_msg *msg);
378 
379 extern void ceph_msg_dump(struct ceph_msg *msg);
380 
381 #endif
382