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
15struct ceph_msg;
16struct ceph_connection;
17
18extern struct workqueue_struct *ceph_msgr_wq;       /* receive work queue */
19
20/*
21 * Ceph defines these callbacks for handling connection events.
22 */
23struct 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
55struct 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
70/*
71 * a single message.  it contains a header (src, dest, message type, etc.),
72 * footer (crc values, mainly), a "front" message body, and possibly a
73 * data payload (stored in some number of pages).
74 */
75struct ceph_msg {
76	struct ceph_msg_header hdr;	/* header */
77	struct ceph_msg_footer footer;	/* footer */
78	struct kvec front;              /* unaligned blobs of message */
79	struct ceph_buffer *middle;
80	struct page **pages;            /* data payload.  NOT OWNER. */
81	unsigned nr_pages;              /* size of page array */
82	struct ceph_pagelist *pagelist; /* instead of pages */
83	struct list_head list_head;
84	struct kref kref;
85	bool front_is_vmalloc;
86	bool more_to_follow;
87	bool needs_out_seq;
88	int front_max;
89
90	struct ceph_msgpool *pool;
91};
92
93struct ceph_msg_pos {
94	int page, page_pos;  /* which page; offset in page */
95	int data_pos;        /* offset in data payload */
96	int did_page_crc;    /* true if we've calculated crc for current page */
97};
98
99/* ceph connection fault delay defaults, for exponential backoff */
100#define BASE_DELAY_INTERVAL	(HZ/2)
101#define MAX_DELAY_INTERVAL	(5 * 60 * HZ)
102
103/*
104 * ceph_connection state bit flags
105 *
106 * QUEUED and BUSY are used together to ensure that only a single
107 * thread is currently opening, reading or writing data to the socket.
108 */
109#define LOSSYTX         0  /* we can close channel or drop messages on errors */
110#define CONNECTING	1
111#define NEGOTIATING	2
112#define KEEPALIVE_PENDING      3
113#define WRITE_PENDING	4  /* we have data ready to send */
114#define QUEUED          5  /* there is work queued on this connection */
115#define BUSY            6  /* work is being done */
116#define STANDBY		8  /* no outgoing messages, socket closed.  we keep
117			    * the ceph_connection around to maintain shared
118			    * state with the peer. */
119#define CLOSED		10 /* we've closed the connection */
120#define SOCK_CLOSED	11 /* socket state changed to closed */
121#define OPENING         13 /* open connection w/ (possibly new) peer */
122#define DEAD            14 /* dead, about to kfree */
123
124/*
125 * A single connection with another host.
126 *
127 * We maintain a queue of outgoing messages, and some session state to
128 * ensure that we can preserve the lossless, ordered delivery of
129 * messages in the case of a TCP disconnect.
130 */
131struct ceph_connection {
132	void *private;
133	atomic_t nref;
134
135	const struct ceph_connection_operations *ops;
136
137	struct ceph_messenger *msgr;
138	struct socket *sock;
139	unsigned long state;	/* connection state (see flags above) */
140	const char *error_msg;  /* error message, if any */
141
142	struct ceph_entity_addr peer_addr; /* peer address */
143	struct ceph_entity_name peer_name; /* peer name */
144	struct ceph_entity_addr peer_addr_for_me;
145	unsigned peer_features;
146	u32 connect_seq;      /* identify the most recent connection
147				 attempt for this connection, client */
148	u32 peer_global_seq;  /* peer's global seq for this connection */
149
150	int auth_retry;       /* true if we need a newer authorizer */
151	void *auth_reply_buf;   /* where to put the authorizer reply */
152	int auth_reply_buf_len;
153
154	struct mutex mutex;
155
156	/* out queue */
157	struct list_head out_queue;
158	struct list_head out_sent;   /* sending or sent but unacked */
159	u64 out_seq;		     /* last message queued for send */
160	bool out_keepalive_pending;
161
162	u64 in_seq, in_seq_acked;  /* last message received, acked */
163
164	/* connection negotiation temps */
165	char in_banner[CEPH_BANNER_MAX_LEN];
166	union {
167		struct {  /* outgoing connection */
168			struct ceph_msg_connect out_connect;
169			struct ceph_msg_connect_reply in_reply;
170		};
171		struct {  /* incoming */
172			struct ceph_msg_connect in_connect;
173			struct ceph_msg_connect_reply out_reply;
174		};
175	};
176	struct ceph_entity_addr actual_peer_addr;
177
178	/* message out temps */
179	struct ceph_msg *out_msg;        /* sending message (== tail of
180					    out_sent) */
181	bool out_msg_done;
182	struct ceph_msg_pos out_msg_pos;
183
184	struct kvec out_kvec[8],         /* sending header/footer data */
185		*out_kvec_cur;
186	int out_kvec_left;   /* kvec's left in out_kvec */
187	int out_skip;        /* skip this many bytes */
188	int out_kvec_bytes;  /* total bytes left */
189	bool out_kvec_is_msg; /* kvec refers to out_msg */
190	int out_more;        /* there is more data after the kvecs */
191	__le64 out_temp_ack; /* for writing an ack */
192
193	/* message in temps */
194	struct ceph_msg_header in_hdr;
195	struct ceph_msg *in_msg;
196	struct ceph_msg_pos in_msg_pos;
197	u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
198
199	char in_tag;         /* protocol control byte */
200	int in_base_pos;     /* bytes read */
201	__le64 in_temp_ack;  /* for reading an ack */
202
203	struct delayed_work work;	    /* send|recv work */
204	unsigned long       delay;          /* current delay interval */
205};
206
207
208extern const char *pr_addr(const struct sockaddr_storage *ss);
209extern int ceph_parse_ips(const char *c, const char *end,
210			  struct ceph_entity_addr *addr,
211			  int max_count, int *count);
212
213
214extern int ceph_msgr_init(void);
215extern void ceph_msgr_exit(void);
216extern void ceph_msgr_flush(void);
217
218extern struct ceph_messenger *ceph_messenger_create(
219	struct ceph_entity_addr *myaddr);
220extern void ceph_messenger_destroy(struct ceph_messenger *);
221
222extern void ceph_con_init(struct ceph_messenger *msgr,
223			  struct ceph_connection *con);
224extern void ceph_con_open(struct ceph_connection *con,
225			  struct ceph_entity_addr *addr);
226extern bool ceph_con_opened(struct ceph_connection *con);
227extern void ceph_con_close(struct ceph_connection *con);
228extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
229extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
230extern void ceph_con_revoke_message(struct ceph_connection *con,
231				  struct ceph_msg *msg);
232extern void ceph_con_keepalive(struct ceph_connection *con);
233extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
234extern void ceph_con_put(struct ceph_connection *con);
235
236extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags);
237extern void ceph_msg_kfree(struct ceph_msg *m);
238
239
240static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
241{
242	kref_get(&msg->kref);
243	return msg;
244}
245extern void ceph_msg_last_put(struct kref *kref);
246static inline void ceph_msg_put(struct ceph_msg *msg)
247{
248	kref_put(&msg->kref, ceph_msg_last_put);
249}
250
251extern void ceph_msg_dump(struct ceph_msg *msg);
252
253#endif
254