xref: /linux-6.15/include/linux/ceph/messenger.h (revision e11da5b4)
1 #ifndef __FS_CEPH_MESSENGER_H
2 #define __FS_CEPH_MESSENGER_H
3 
4 #include <linux/kref.h>
5 #include <linux/mutex.h>
6 #include <linux/net.h>
7 #include <linux/radix-tree.h>
8 #include <linux/uio.h>
9 #include <linux/version.h>
10 #include <linux/workqueue.h>
11 
12 #include "types.h"
13 #include "buffer.h"
14 
15 struct ceph_msg;
16 struct ceph_connection;
17 
18 extern struct workqueue_struct *ceph_msgr_wq;       /* receive work queue */
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 	int (*get_authorizer) (struct ceph_connection *con,
32 			       void **buf, int *len, int *proto,
33 			       void **reply_buf, int *reply_len, int force_new);
34 	int (*verify_authorizer_reply) (struct ceph_connection *con, int len);
35 	int (*invalidate_authorizer)(struct ceph_connection *con);
36 
37 	/* protocol version mismatch */
38 	void (*bad_proto) (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 
52 /* use format string %s%d */
53 #define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
54 
55 struct ceph_messenger {
56 	struct ceph_entity_inst inst;    /* my name+address */
57 	struct ceph_entity_addr my_enc_addr;
58 	struct page *zero_page;          /* used in certain error cases */
59 
60 	bool nocrc;
61 
62 	/*
63 	 * the global_seq counts connections i (attempt to) initiate
64 	 * in order to disambiguate certain connect race conditions.
65 	 */
66 	u32 global_seq;
67 	spinlock_t global_seq_lock;
68 
69 	u32 supported_features;
70 	u32 required_features;
71 };
72 
73 /*
74  * a single message.  it contains a header (src, dest, message type, etc.),
75  * footer (crc values, mainly), a "front" message body, and possibly a
76  * data payload (stored in some number of pages).
77  */
78 struct ceph_msg {
79 	struct ceph_msg_header hdr;	/* header */
80 	struct ceph_msg_footer footer;	/* footer */
81 	struct kvec front;              /* unaligned blobs of message */
82 	struct ceph_buffer *middle;
83 	struct page **pages;            /* data payload.  NOT OWNER. */
84 	unsigned nr_pages;              /* size of page array */
85 	struct ceph_pagelist *pagelist; /* instead of pages */
86 	struct list_head list_head;
87 	struct kref kref;
88 	struct bio  *bio;		/* instead of pages/pagelist */
89 	struct bio  *bio_iter;		/* bio iterator */
90 	int bio_seg;			/* current bio segment */
91 	struct ceph_pagelist *trail;	/* the trailing part of the data */
92 	bool front_is_vmalloc;
93 	bool more_to_follow;
94 	bool needs_out_seq;
95 	int front_max;
96 
97 	struct ceph_msgpool *pool;
98 };
99 
100 struct ceph_msg_pos {
101 	int page, page_pos;  /* which page; offset in page */
102 	int data_pos;        /* offset in data payload */
103 	int did_page_crc;    /* true if we've calculated crc for current page */
104 };
105 
106 /* ceph connection fault delay defaults, for exponential backoff */
107 #define BASE_DELAY_INTERVAL	(HZ/2)
108 #define MAX_DELAY_INTERVAL	(5 * 60 * HZ)
109 
110 /*
111  * ceph_connection state bit flags
112  *
113  * QUEUED and BUSY are used together to ensure that only a single
114  * thread is currently opening, reading or writing data to the socket.
115  */
116 #define LOSSYTX         0  /* we can close channel or drop messages on errors */
117 #define CONNECTING	1
118 #define NEGOTIATING	2
119 #define KEEPALIVE_PENDING      3
120 #define WRITE_PENDING	4  /* we have data ready to send */
121 #define QUEUED          5  /* there is work queued on this connection */
122 #define BUSY            6  /* work is being done */
123 #define STANDBY		8  /* no outgoing messages, socket closed.  we keep
124 			    * the ceph_connection around to maintain shared
125 			    * state with the peer. */
126 #define CLOSED		10 /* we've closed the connection */
127 #define SOCK_CLOSED	11 /* socket state changed to closed */
128 #define OPENING         13 /* open connection w/ (possibly new) peer */
129 #define DEAD            14 /* dead, about to kfree */
130 
131 /*
132  * A single connection with another host.
133  *
134  * We maintain a queue of outgoing messages, and some session state to
135  * ensure that we can preserve the lossless, ordered delivery of
136  * messages in the case of a TCP disconnect.
137  */
138 struct ceph_connection {
139 	void *private;
140 	atomic_t nref;
141 
142 	const struct ceph_connection_operations *ops;
143 
144 	struct ceph_messenger *msgr;
145 	struct socket *sock;
146 	unsigned long state;	/* connection state (see flags above) */
147 	const char *error_msg;  /* error message, if any */
148 
149 	struct ceph_entity_addr peer_addr; /* peer address */
150 	struct ceph_entity_name peer_name; /* peer name */
151 	struct ceph_entity_addr peer_addr_for_me;
152 	unsigned peer_features;
153 	u32 connect_seq;      /* identify the most recent connection
154 				 attempt for this connection, client */
155 	u32 peer_global_seq;  /* peer's global seq for this connection */
156 
157 	int auth_retry;       /* true if we need a newer authorizer */
158 	void *auth_reply_buf;   /* where to put the authorizer reply */
159 	int auth_reply_buf_len;
160 
161 	struct mutex mutex;
162 
163 	/* out queue */
164 	struct list_head out_queue;
165 	struct list_head out_sent;   /* sending or sent but unacked */
166 	u64 out_seq;		     /* last message queued for send */
167 	bool out_keepalive_pending;
168 
169 	u64 in_seq, in_seq_acked;  /* last message received, acked */
170 
171 	/* connection negotiation temps */
172 	char in_banner[CEPH_BANNER_MAX_LEN];
173 	union {
174 		struct {  /* outgoing connection */
175 			struct ceph_msg_connect out_connect;
176 			struct ceph_msg_connect_reply in_reply;
177 		};
178 		struct {  /* incoming */
179 			struct ceph_msg_connect in_connect;
180 			struct ceph_msg_connect_reply out_reply;
181 		};
182 	};
183 	struct ceph_entity_addr actual_peer_addr;
184 
185 	/* message out temps */
186 	struct ceph_msg *out_msg;        /* sending message (== tail of
187 					    out_sent) */
188 	bool out_msg_done;
189 	struct ceph_msg_pos out_msg_pos;
190 
191 	struct kvec out_kvec[8],         /* sending header/footer data */
192 		*out_kvec_cur;
193 	int out_kvec_left;   /* kvec's left in out_kvec */
194 	int out_skip;        /* skip this many bytes */
195 	int out_kvec_bytes;  /* total bytes left */
196 	bool out_kvec_is_msg; /* kvec refers to out_msg */
197 	int out_more;        /* there is more data after the kvecs */
198 	__le64 out_temp_ack; /* for writing an ack */
199 
200 	/* message in temps */
201 	struct ceph_msg_header in_hdr;
202 	struct ceph_msg *in_msg;
203 	struct ceph_msg_pos in_msg_pos;
204 	u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
205 
206 	char in_tag;         /* protocol control byte */
207 	int in_base_pos;     /* bytes read */
208 	__le64 in_temp_ack;  /* for reading an ack */
209 
210 	struct delayed_work work;	    /* send|recv work */
211 	unsigned long       delay;          /* current delay interval */
212 };
213 
214 
215 extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
216 extern int ceph_parse_ips(const char *c, const char *end,
217 			  struct ceph_entity_addr *addr,
218 			  int max_count, int *count);
219 
220 
221 extern int ceph_msgr_init(void);
222 extern void ceph_msgr_exit(void);
223 extern void ceph_msgr_flush(void);
224 
225 extern struct ceph_messenger *ceph_messenger_create(
226 	struct ceph_entity_addr *myaddr,
227 	u32 features, u32 required);
228 extern void ceph_messenger_destroy(struct ceph_messenger *);
229 
230 extern void ceph_con_init(struct ceph_messenger *msgr,
231 			  struct ceph_connection *con);
232 extern void ceph_con_open(struct ceph_connection *con,
233 			  struct ceph_entity_addr *addr);
234 extern bool ceph_con_opened(struct ceph_connection *con);
235 extern void ceph_con_close(struct ceph_connection *con);
236 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
237 extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
238 extern void ceph_con_revoke_message(struct ceph_connection *con,
239 				  struct ceph_msg *msg);
240 extern void ceph_con_keepalive(struct ceph_connection *con);
241 extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
242 extern void ceph_con_put(struct ceph_connection *con);
243 
244 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags);
245 extern void ceph_msg_kfree(struct ceph_msg *m);
246 
247 
248 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
249 {
250 	kref_get(&msg->kref);
251 	return msg;
252 }
253 extern void ceph_msg_last_put(struct kref *kref);
254 static inline void ceph_msg_put(struct ceph_msg *msg)
255 {
256 	kref_put(&msg->kref, ceph_msg_last_put);
257 }
258 
259 extern void ceph_msg_dump(struct ceph_msg *msg);
260 
261 #endif
262