libceph: implement pages array cursor
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / linux / ceph / messenger.h
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/workqueue.h>
10
11 #include <linux/ceph/types.h>
12 #include <linux/ceph/buffer.h>
13
14 struct ceph_msg;
15 struct ceph_connection;
16
17 /*
18 * Ceph defines these callbacks for handling connection events.
19 */
20 struct ceph_connection_operations {
21 struct ceph_connection *(*get)(struct ceph_connection *);
22 void (*put)(struct ceph_connection *);
23
24 /* handle an incoming message. */
25 void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
26
27 /* authorize an outgoing connection */
28 struct ceph_auth_handshake *(*get_authorizer) (
29 struct ceph_connection *con,
30 int *proto, int force_new);
31 int (*verify_authorizer_reply) (struct ceph_connection *con, int len);
32 int (*invalidate_authorizer)(struct ceph_connection *con);
33
34 /* there was some error on the socket (disconnect, whatever) */
35 void (*fault) (struct ceph_connection *con);
36
37 /* a remote host as terminated a message exchange session, and messages
38 * we sent (or they tried to send us) may be lost. */
39 void (*peer_reset) (struct ceph_connection *con);
40
41 struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
42 struct ceph_msg_header *hdr,
43 int *skip);
44 };
45
46 /* use format string %s%d */
47 #define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
48
49 struct ceph_messenger {
50 struct ceph_entity_inst inst; /* my name+address */
51 struct ceph_entity_addr my_enc_addr;
52
53 atomic_t stopping;
54 bool nocrc;
55
56 /*
57 * the global_seq counts connections i (attempt to) initiate
58 * in order to disambiguate certain connect race conditions.
59 */
60 u32 global_seq;
61 spinlock_t global_seq_lock;
62
63 u32 supported_features;
64 u32 required_features;
65 };
66
67 #define ceph_msg_has_pages(m) ((m)->p.type == CEPH_MSG_DATA_PAGES)
68 #define ceph_msg_has_pagelist(m) ((m)->l.type == CEPH_MSG_DATA_PAGELIST)
69 #ifdef CONFIG_BLOCK
70 #define ceph_msg_has_bio(m) ((m)->b.type == CEPH_MSG_DATA_BIO)
71 #endif /* CONFIG_BLOCK */
72 #define ceph_msg_has_trail(m) ((m)->t.type == CEPH_MSG_DATA_PAGELIST)
73
74 enum ceph_msg_data_type {
75 CEPH_MSG_DATA_NONE, /* message contains no data payload */
76 CEPH_MSG_DATA_PAGES, /* data source/destination is a page array */
77 CEPH_MSG_DATA_PAGELIST, /* data source/destination is a pagelist */
78 #ifdef CONFIG_BLOCK
79 CEPH_MSG_DATA_BIO, /* data source/destination is a bio list */
80 #endif /* CONFIG_BLOCK */
81 };
82
83 static __inline__ bool ceph_msg_data_type_valid(enum ceph_msg_data_type type)
84 {
85 switch (type) {
86 case CEPH_MSG_DATA_NONE:
87 case CEPH_MSG_DATA_PAGES:
88 case CEPH_MSG_DATA_PAGELIST:
89 #ifdef CONFIG_BLOCK
90 case CEPH_MSG_DATA_BIO:
91 #endif /* CONFIG_BLOCK */
92 return true;
93 default:
94 return false;
95 }
96 }
97
98 struct ceph_msg_data_cursor {
99 bool last_piece; /* now at last piece of data item */
100 union {
101 #ifdef CONFIG_BLOCK
102 struct { /* bio */
103 struct bio *bio; /* bio from list */
104 unsigned int vector_index; /* vector from bio */
105 unsigned int vector_offset; /* bytes from vector */
106 };
107 #endif /* CONFIG_BLOCK */
108 struct { /* pages */
109 size_t resid; /* bytes from array */
110 unsigned int page_offset; /* offset in page */
111 unsigned short page_index; /* index in array */
112 unsigned short page_count; /* pages in array */
113 };
114 struct { /* pagelist */
115 struct page *page; /* page from list */
116 size_t offset; /* bytes from list */
117 };
118 };
119 };
120
121 struct ceph_msg_data {
122 enum ceph_msg_data_type type;
123 union {
124 #ifdef CONFIG_BLOCK
125 struct {
126 struct bio *bio_iter; /* iterator */
127 struct bio *bio;
128 unsigned int bio_seg; /* current seg in bio */
129 };
130 #endif /* CONFIG_BLOCK */
131 struct {
132 struct page **pages; /* NOT OWNER. */
133 size_t length; /* total # bytes */
134 unsigned int alignment; /* first page */
135 };
136 struct ceph_pagelist *pagelist;
137 };
138 struct ceph_msg_data_cursor cursor; /* pagelist only */
139 };
140
141 /*
142 * a single message. it contains a header (src, dest, message type, etc.),
143 * footer (crc values, mainly), a "front" message body, and possibly a
144 * data payload (stored in some number of pages).
145 */
146 struct ceph_msg {
147 struct ceph_msg_header hdr; /* header */
148 struct ceph_msg_footer footer; /* footer */
149 struct kvec front; /* unaligned blobs of message */
150 struct ceph_buffer *middle;
151
152 /* data payload */
153 struct ceph_msg_data p; /* pages */
154 struct ceph_msg_data l; /* pagelist */
155 #ifdef CONFIG_BLOCK
156 struct ceph_msg_data b; /* bio */
157 #endif /* CONFIG_BLOCK */
158 struct ceph_msg_data t; /* trail */
159
160 struct ceph_connection *con;
161 struct list_head list_head; /* links for connection lists */
162
163 struct kref kref;
164 bool front_is_vmalloc;
165 bool more_to_follow;
166 bool needs_out_seq;
167 int front_max;
168 unsigned long ack_stamp; /* tx: when we were acked */
169
170 struct ceph_msgpool *pool;
171 };
172
173 struct ceph_msg_pos {
174 int page, page_pos; /* which page; offset in page */
175 int data_pos; /* offset in data payload */
176 bool did_page_crc; /* true if we've calculated crc for current page */
177 };
178
179 /* ceph connection fault delay defaults, for exponential backoff */
180 #define BASE_DELAY_INTERVAL (HZ/2)
181 #define MAX_DELAY_INTERVAL (5 * 60 * HZ)
182
183 /*
184 * A single connection with another host.
185 *
186 * We maintain a queue of outgoing messages, and some session state to
187 * ensure that we can preserve the lossless, ordered delivery of
188 * messages in the case of a TCP disconnect.
189 */
190 struct ceph_connection {
191 void *private;
192
193 const struct ceph_connection_operations *ops;
194
195 struct ceph_messenger *msgr;
196
197 atomic_t sock_state;
198 struct socket *sock;
199 struct ceph_entity_addr peer_addr; /* peer address */
200 struct ceph_entity_addr peer_addr_for_me;
201
202 unsigned long flags;
203 unsigned long state;
204 const char *error_msg; /* error message, if any */
205
206 struct ceph_entity_name peer_name; /* peer name */
207
208 unsigned peer_features;
209 u32 connect_seq; /* identify the most recent connection
210 attempt for this connection, client */
211 u32 peer_global_seq; /* peer's global seq for this connection */
212
213 int auth_retry; /* true if we need a newer authorizer */
214 void *auth_reply_buf; /* where to put the authorizer reply */
215 int auth_reply_buf_len;
216
217 struct mutex mutex;
218
219 /* out queue */
220 struct list_head out_queue;
221 struct list_head out_sent; /* sending or sent but unacked */
222 u64 out_seq; /* last message queued for send */
223
224 u64 in_seq, in_seq_acked; /* last message received, acked */
225
226 /* connection negotiation temps */
227 char in_banner[CEPH_BANNER_MAX_LEN];
228 struct ceph_msg_connect out_connect;
229 struct ceph_msg_connect_reply in_reply;
230 struct ceph_entity_addr actual_peer_addr;
231
232 /* message out temps */
233 struct ceph_msg *out_msg; /* sending message (== tail of
234 out_sent) */
235 bool out_msg_done;
236 struct ceph_msg_pos out_msg_pos;
237
238 struct kvec out_kvec[8], /* sending header/footer data */
239 *out_kvec_cur;
240 int out_kvec_left; /* kvec's left in out_kvec */
241 int out_skip; /* skip this many bytes */
242 int out_kvec_bytes; /* total bytes left */
243 bool out_kvec_is_msg; /* kvec refers to out_msg */
244 int out_more; /* there is more data after the kvecs */
245 __le64 out_temp_ack; /* for writing an ack */
246
247 /* message in temps */
248 struct ceph_msg_header in_hdr;
249 struct ceph_msg *in_msg;
250 struct ceph_msg_pos in_msg_pos;
251 u32 in_front_crc, in_middle_crc, in_data_crc; /* calculated crc */
252
253 char in_tag; /* protocol control byte */
254 int in_base_pos; /* bytes read */
255 __le64 in_temp_ack; /* for reading an ack */
256
257 struct delayed_work work; /* send|recv work */
258 unsigned long delay; /* current delay interval */
259 };
260
261
262 extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
263 extern int ceph_parse_ips(const char *c, const char *end,
264 struct ceph_entity_addr *addr,
265 int max_count, int *count);
266
267
268 extern int ceph_msgr_init(void);
269 extern void ceph_msgr_exit(void);
270 extern void ceph_msgr_flush(void);
271
272 extern void ceph_messenger_init(struct ceph_messenger *msgr,
273 struct ceph_entity_addr *myaddr,
274 u32 supported_features,
275 u32 required_features,
276 bool nocrc);
277
278 extern void ceph_con_init(struct ceph_connection *con, void *private,
279 const struct ceph_connection_operations *ops,
280 struct ceph_messenger *msgr);
281 extern void ceph_con_open(struct ceph_connection *con,
282 __u8 entity_type, __u64 entity_num,
283 struct ceph_entity_addr *addr);
284 extern bool ceph_con_opened(struct ceph_connection *con);
285 extern void ceph_con_close(struct ceph_connection *con);
286 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
287
288 extern void ceph_msg_revoke(struct ceph_msg *msg);
289 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
290
291 extern void ceph_con_keepalive(struct ceph_connection *con);
292
293 extern void ceph_msg_data_set_pages(struct ceph_msg *msg, struct page **pages,
294 size_t length, size_t alignment);
295 extern void ceph_msg_data_set_pagelist(struct ceph_msg *msg,
296 struct ceph_pagelist *pagelist);
297 extern void ceph_msg_data_set_bio(struct ceph_msg *msg, struct bio *bio);
298 extern void ceph_msg_data_set_trail(struct ceph_msg *msg,
299 struct ceph_pagelist *trail);
300
301 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
302 bool can_fail);
303 extern void ceph_msg_kfree(struct ceph_msg *m);
304
305
306 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
307 {
308 kref_get(&msg->kref);
309 return msg;
310 }
311 extern void ceph_msg_last_put(struct kref *kref);
312 static inline void ceph_msg_put(struct ceph_msg *msg)
313 {
314 kref_put(&msg->kref, ceph_msg_last_put);
315 }
316
317 extern void ceph_msg_dump(struct ceph_msg *msg);
318
319 #endif