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gerrit-public.fairphone.software / kernel / msm-4.19 / 859e7b149362475672e2a996f29b8f45cbb34d82 / . / fs / ceph / messenger.h
blob: dcd98b64dca97d44a04694fc4c90fcd9f9d40ad2 [file] [log] [blame]
Sage Weil31b80062009-10-06 11:31:13 -0700[diff] [blame]1#ifndef __FS_CEPH_MESSENGER_H
2#define __FS_CEPH_MESSENGER_H
3
4#include <linux/mutex.h>
5#include <linux/net.h>
6#include <linux/radix-tree.h>
7#include <linux/uio.h>
8#include <linux/version.h>
9#include <linux/workqueue.h>
10
11#include "types.h"
12#include "buffer.h"
13
14struct ceph_msg;
15struct ceph_connection;
16
17extern struct workqueue_struct *ceph_msgr_wq; /* receive work queue */
18
19/*
20 * Ceph defines these callbacks for handling connection events.
21 */
22struct ceph_connection_operations {
23 struct ceph_connection *(*get)(struct ceph_connection *);
24 void (*put)(struct ceph_connection *);
25
26 /* handle an incoming message. */
27 void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
28
29 /* protocol version mismatch */
30 void (*bad_proto) (struct ceph_connection *con);
31
32 /* there was some error on the socket (disconnect, whatever) */
33 void (*fault) (struct ceph_connection *con);
34
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);
38
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,
46 int want);
47};
48
49extern const char *ceph_name_type_str(int t);
50
51/* use format string %s%d */
52#define ENTITY_NAME(n) ceph_name_type_str((n).type), le64_to_cpu((n).num)
53
54struct ceph_messenger {
55 struct ceph_entity_inst inst; /* my name+address */
56 struct page *zero_page; /* used in certain error cases */
57
58 bool nocrc;
59
60 /*
61 * the global_seq counts connections i (attempt to) initiate
62 * in order to disambiguate certain connect race conditions.
63 */
64 u32 global_seq;
65 spinlock_t global_seq_lock;
66};
67
68/*
69 * a single message. it contains a header (src, dest, message type, etc.),
70 * footer (crc values, mainly), a "front" message body, and possibly a
71 * data payload (stored in some number of pages).
72 */
73struct ceph_msg {
74 struct ceph_msg_header hdr; /* header */
75 struct ceph_msg_footer footer; /* footer */
76 struct kvec front; /* unaligned blobs of message */
77 struct ceph_buffer *middle;
78 struct page **pages; /* data payload. NOT OWNER. */
79 unsigned nr_pages; /* size of page array */
80 struct list_head list_head;
81 atomic_t nref;
82 bool front_is_vmalloc;
83 bool more_to_follow;
84 int front_max;
85
86 struct ceph_msgpool *pool;
87};
88
89struct ceph_msg_pos {
90 int page, page_pos; /* which page; offset in page */
91 int data_pos; /* offset in data payload */
92 int did_page_crc; /* true if we've calculated crc for current page */
93};
94
95/* ceph connection fault delay defaults, for exponential backoff */
96#define BASE_DELAY_INTERVAL (HZ/2)
97#define MAX_DELAY_INTERVAL (5 * 60 * HZ)
98
99/*
100 * ceph_connection state bit flags
101 *
102 * QUEUED and BUSY are used together to ensure that only a single
103 * thread is currently opening, reading or writing data to the socket.
104 */
105#define LOSSYTX 0 /* we can close channel or drop messages on errors */
106#define LOSSYRX 1 /* peer may reset/drop messages */
107#define CONNECTING 2
108#define KEEPALIVE_PENDING 3
109#define WRITE_PENDING 4 /* we have data ready to send */
110#define QUEUED 5 /* there is work queued on this connection */
111#define BUSY 6 /* work is being done */
112#define STANDBY 8 /* no outgoing messages, socket closed. we keep
113 * the ceph_connection around to maintain shared
114 * state with the peer. */
115#define CLOSED 10 /* we've closed the connection */
116#define SOCK_CLOSED 11 /* socket state changed to closed */
117#define REGISTERED 12 /* connection appears in con_tree */
118#define OPENING 13 /* open connection w/ (possibly new) peer */
119#define DEAD 14 /* dead, about to kfree */
120
121/*
122 * A single connection with another host.
123 *
124 * We maintain a queue of outgoing messages, and some session state to
125 * ensure that we can preserve the lossless, ordered delivery of
126 * messages in the case of a TCP disconnect.
127 */
128struct ceph_connection {
129 void *private;
130 atomic_t nref;
131
132 const struct ceph_connection_operations *ops;
133
134 struct ceph_messenger *msgr;
135 struct socket *sock;
136 unsigned long state; /* connection state (see flags above) */
137 const char *error_msg; /* error message, if any */
138
139 struct ceph_entity_addr peer_addr; /* peer address */
140 struct ceph_entity_name peer_name; /* peer name */
141 struct ceph_entity_addr peer_addr_for_me;
142 u32 connect_seq; /* identify the most recent connection
143 attempt for this connection, client */
144 u32 peer_global_seq; /* peer's global seq for this connection */
145
146 /* out queue */
147 struct mutex out_mutex;
148 struct list_head out_queue;
149 struct list_head out_sent; /* sending or sent but unacked */
150 u64 out_seq; /* last message queued for send */
151 u64 out_seq_sent; /* last message sent */
152 bool out_keepalive_pending;
153
154 u64 in_seq, in_seq_acked; /* last message received, acked */
155
156 /* connection negotiation temps */
157 char in_banner[CEPH_BANNER_MAX_LEN];
158 union {
159 struct { /* outgoing connection */
160 struct ceph_msg_connect out_connect;
161 struct ceph_msg_connect_reply in_reply;
162 };
163 struct { /* incoming */
164 struct ceph_msg_connect in_connect;
165 struct ceph_msg_connect_reply out_reply;
166 };
167 };
168 struct ceph_entity_addr actual_peer_addr;
169
170 /* message out temps */
171 struct ceph_msg *out_msg; /* sending message (== tail of
172 out_sent) */
173 struct ceph_msg_pos out_msg_pos;
174
175 struct kvec out_kvec[8], /* sending header/footer data */
176 *out_kvec_cur;
177 int out_kvec_left; /* kvec's left in out_kvec */
178 int out_skip; /* skip this many bytes */
179 int out_kvec_bytes; /* total bytes left */
180 bool out_kvec_is_msg; /* kvec refers to out_msg */
181 int out_more; /* there is more data after the kvecs */
182 __le64 out_temp_ack; /* for writing an ack */
183
184 /* message in temps */
185 struct ceph_msg_header in_hdr;
186 struct ceph_msg *in_msg;
187 struct ceph_msg_pos in_msg_pos;
188 u32 in_front_crc, in_middle_crc, in_data_crc; /* calculated crc */
189
190 char in_tag; /* protocol control byte */
191 int in_base_pos; /* bytes read */
192 __le64 in_temp_ack; /* for reading an ack */
193
194 struct delayed_work work; /* send|recv work */
195 unsigned long delay; /* current delay interval */
196};
197
198
199extern const char *pr_addr(const struct sockaddr_storage *ss);
200extern int ceph_parse_ips(const char *c, const char *end,
201 struct ceph_entity_addr *addr,
202 int max_count, int *count);
203
204
205extern int ceph_msgr_init(void);
206extern void ceph_msgr_exit(void);
207
208extern struct ceph_messenger *ceph_messenger_create(
209 struct ceph_entity_addr *myaddr);
210extern void ceph_messenger_destroy(struct ceph_messenger *);
211
212extern void ceph_con_init(struct ceph_messenger *msgr,
213 struct ceph_connection *con);
214extern void ceph_con_shutdown(struct ceph_connection *con);
215extern void ceph_con_open(struct ceph_connection *con,
216 struct ceph_entity_addr *addr);
217extern void ceph_con_close(struct ceph_connection *con);
218extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
219extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
220extern void ceph_con_keepalive(struct ceph_connection *con);
221extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
222extern void ceph_con_put(struct ceph_connection *con);
223
224extern struct ceph_msg *ceph_msg_new(int type, int front_len,
225 int page_len, int page_off,
226 struct page **pages);
227extern void ceph_msg_kfree(struct ceph_msg *m);
228
229extern struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
230 struct ceph_msg_header *hdr);
231extern int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg);
232
233
234static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
235{
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);
239 return msg;
240}
241extern void ceph_msg_put(struct ceph_msg *msg);
242
243#endif