1 #ifndef __FS_CEPH_MESSENGER_H
2 #define __FS_CEPH_MESSENGER_H
4 #include <linux/mutex.h>
6 #include <linux/radix-tree.h>
8 #include <linux/version.h>
9 #include <linux/workqueue.h>
15 struct ceph_connection;
17 extern struct workqueue_struct *ceph_msgr_wq; /* receive work queue */
20 * Ceph defines these callbacks for handling connection events.
22 struct ceph_connection_operations {
23 struct ceph_connection *(*get)(struct ceph_connection *);
24 void (*put)(struct ceph_connection *);
26 /* handle an incoming message. */
27 void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
29 /* protocol version mismatch */
30 void (*bad_proto) (struct ceph_connection *con);
32 /* there was some error on the socket (disconnect, whatever) */
33 void (*fault) (struct ceph_connection *con);
35 /* a remote host as terminated a message exchange session, and messages
36 * we sent (or they tried to send us) may be lost. */
37 void (*peer_reset) (struct ceph_connection *con);
39 struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
40 struct ceph_msg_header *hdr);
41 int (*alloc_middle) (struct ceph_connection *con,
42 struct ceph_msg *msg);
43 /* an incoming message has a data payload; tell me what pages I
44 * should read the data into. */
45 int (*prepare_pages) (struct ceph_connection *con, struct ceph_msg *m,
49 extern const char *ceph_name_type_str(int t);
51 /* use format string %s%d */
52 #define ENTITY_NAME(n) ceph_name_type_str((n).type), le64_to_cpu((n).num)
54 struct ceph_messenger {
55 struct ceph_entity_inst inst; /* my name+address */
56 struct ceph_entity_addr my_enc_addr;
57 struct page *zero_page; /* used in certain error cases */
62 * the global_seq counts connections i (attempt to) initiate
63 * in order to disambiguate certain connect race conditions.
66 spinlock_t global_seq_lock;
70 * a single message. it contains a header (src, dest, message type, etc.),
71 * footer (crc values, mainly), a "front" message body, and possibly a
72 * data payload (stored in some number of pages).
75 struct ceph_msg_header hdr; /* header */
76 struct ceph_msg_footer footer; /* footer */
77 struct kvec front; /* unaligned blobs of message */
78 struct ceph_buffer *middle;
79 struct page **pages; /* data payload. NOT OWNER. */
80 unsigned nr_pages; /* size of page array */
81 struct list_head list_head;
83 bool front_is_vmalloc;
87 struct ceph_msgpool *pool;
91 int page, page_pos; /* which page; offset in page */
92 int data_pos; /* offset in data payload */
93 int did_page_crc; /* true if we've calculated crc for current page */
96 /* ceph connection fault delay defaults, for exponential backoff */
97 #define BASE_DELAY_INTERVAL (HZ/2)
98 #define MAX_DELAY_INTERVAL (5 * 60 * HZ)
101 * ceph_connection state bit flags
103 * QUEUED and BUSY are used together to ensure that only a single
104 * thread is currently opening, reading or writing data to the socket.
106 #define LOSSYTX 0 /* we can close channel or drop messages on errors */
108 #define NEGOTIATING 2
109 #define KEEPALIVE_PENDING 3
110 #define WRITE_PENDING 4 /* we have data ready to send */
111 #define QUEUED 5 /* there is work queued on this connection */
112 #define BUSY 6 /* work is being done */
113 #define STANDBY 8 /* no outgoing messages, socket closed. we keep
114 * the ceph_connection around to maintain shared
115 * state with the peer. */
116 #define CLOSED 10 /* we've closed the connection */
117 #define SOCK_CLOSED 11 /* socket state changed to closed */
118 #define REGISTERED 12 /* connection appears in con_tree */
119 #define OPENING 13 /* open connection w/ (possibly new) peer */
120 #define DEAD 14 /* dead, about to kfree */
123 * A single connection with another host.
125 * We maintain a queue of outgoing messages, and some session state to
126 * ensure that we can preserve the lossless, ordered delivery of
127 * messages in the case of a TCP disconnect.
129 struct ceph_connection {
133 const struct ceph_connection_operations *ops;
135 struct ceph_messenger *msgr;
137 unsigned long state; /* connection state (see flags above) */
138 const char *error_msg; /* error message, if any */
140 struct ceph_entity_addr peer_addr; /* peer address */
141 struct ceph_entity_name peer_name; /* peer name */
142 struct ceph_entity_addr peer_addr_for_me;
143 u32 connect_seq; /* identify the most recent connection
144 attempt for this connection, client */
145 u32 peer_global_seq; /* peer's global seq for this connection */
148 struct mutex out_mutex;
149 struct list_head out_queue;
150 struct list_head out_sent; /* sending or sent but unacked */
151 u64 out_seq; /* last message queued for send */
152 u64 out_seq_sent; /* last message sent */
153 bool out_keepalive_pending;
155 u64 in_seq, in_seq_acked; /* last message received, acked */
157 /* connection negotiation temps */
158 char in_banner[CEPH_BANNER_MAX_LEN];
160 struct { /* outgoing connection */
161 struct ceph_msg_connect out_connect;
162 struct ceph_msg_connect_reply in_reply;
164 struct { /* incoming */
165 struct ceph_msg_connect in_connect;
166 struct ceph_msg_connect_reply out_reply;
169 struct ceph_entity_addr actual_peer_addr;
171 /* message out temps */
172 struct ceph_msg *out_msg; /* sending message (== tail of
174 struct ceph_msg_pos out_msg_pos;
176 struct kvec out_kvec[8], /* sending header/footer data */
178 int out_kvec_left; /* kvec's left in out_kvec */
179 int out_skip; /* skip this many bytes */
180 int out_kvec_bytes; /* total bytes left */
181 bool out_kvec_is_msg; /* kvec refers to out_msg */
182 int out_more; /* there is more data after the kvecs */
183 __le64 out_temp_ack; /* for writing an ack */
185 /* message in temps */
186 struct ceph_msg_header in_hdr;
187 struct ceph_msg *in_msg;
188 struct ceph_msg_pos in_msg_pos;
189 u32 in_front_crc, in_middle_crc, in_data_crc; /* calculated crc */
191 char in_tag; /* protocol control byte */
192 int in_base_pos; /* bytes read */
193 __le64 in_temp_ack; /* for reading an ack */
195 struct delayed_work work; /* send|recv work */
196 unsigned long delay; /* current delay interval */
200 extern const char *pr_addr(const struct sockaddr_storage *ss);
201 extern int ceph_parse_ips(const char *c, const char *end,
202 struct ceph_entity_addr *addr,
203 int max_count, int *count);
206 extern int ceph_msgr_init(void);
207 extern void ceph_msgr_exit(void);
209 extern struct ceph_messenger *ceph_messenger_create(
210 struct ceph_entity_addr *myaddr);
211 extern void ceph_messenger_destroy(struct ceph_messenger *);
213 extern void ceph_con_init(struct ceph_messenger *msgr,
214 struct ceph_connection *con);
215 extern void ceph_con_open(struct ceph_connection *con,
216 struct ceph_entity_addr *addr);
217 extern void ceph_con_close(struct ceph_connection *con);
218 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
219 extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
220 extern void ceph_con_keepalive(struct ceph_connection *con);
221 extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
222 extern void ceph_con_put(struct ceph_connection *con);
224 extern struct ceph_msg *ceph_msg_new(int type, int front_len,
225 int page_len, int page_off,
226 struct page **pages);
227 extern void ceph_msg_kfree(struct ceph_msg *m);
229 extern struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
230 struct ceph_msg_header *hdr);
231 extern int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg);
234 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
236 dout("ceph_msg_get %p %d -> %d\n", msg, atomic_read(&msg->nref),
237 atomic_read(&msg->nref)+1);
238 atomic_inc(&msg->nref);
241 extern void ceph_msg_put(struct ceph_msg *msg);