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         struct page     *page;          /* current page in pagelist */
 101         size_t          offset;         /* pagelist bytes consumed */
 102 };
 103
 104 struct ceph_msg_data {
 105         enum ceph_msg_data_type         type;
 106         union {
 107 #ifdef CONFIG_BLOCK
 108                 struct {
 109                         struct bio      *bio_iter;      /* iterator */
 110                         struct bio      *bio;
 111                         unsigned int    bio_seg;        /* current seg in bio */
 112                 };
 113 #endif /* CONFIG_BLOCK */
 114                 struct {
 115                         struct page     **pages;        /* NOT OWNER. */
 116                         size_t          length;         /* total # bytes */
 117                         unsigned int    alignment;      /* first page */
 118                 };
 119                 struct ceph_pagelist    *pagelist;
 120         };
 121         struct ceph_msg_data_cursor     cursor;         /* pagelist only */
 122 };
 123
 124 /*
 125  * a single message.  it contains a header (src, dest, message type, etc.),
 126  * footer (crc values, mainly), a "front" message body, and possibly a
 127  * data payload (stored in some number of pages).
 128  */
 129 struct ceph_msg {
 130         struct ceph_msg_header hdr;     /* header */
 131         struct ceph_msg_footer footer;  /* footer */
 132         struct kvec front;              /* unaligned blobs of message */
 133         struct ceph_buffer *middle;
 134
 135         /* data payload */
 136         struct ceph_msg_data    p;      /* pages */
 137         struct ceph_msg_data    l;      /* pagelist */
 138 #ifdef CONFIG_BLOCK
 139         struct ceph_msg_data    b;      /* bio */
 140 #endif /* CONFIG_BLOCK */
 141         struct ceph_msg_data    t;      /* trail */
 142
 143         struct ceph_connection *con;
 144         struct list_head list_head;     /* links for connection lists */
 145
 146         struct kref kref;
 147         bool front_is_vmalloc;
 148         bool more_to_follow;
 149         bool needs_out_seq;
 150         int front_max;
 151         unsigned long ack_stamp;        /* tx: when we were acked */
 152
 153         struct ceph_msgpool *pool;
 154 };
 155
 156 struct ceph_msg_pos {
 157         int page, page_pos;  /* which page; offset in page */
 158         int data_pos;        /* offset in data payload */
 159         bool did_page_crc;   /* true if we've calculated crc for current page */
 160 };
 161
 162 /* ceph connection fault delay defaults, for exponential backoff */
 163 #define BASE_DELAY_INTERVAL     (HZ/2)
 164 #define MAX_DELAY_INTERVAL      (5 * 60 * HZ)
 165
 166 /*
 167  * A single connection with another host.
 168  *
 169  * We maintain a queue of outgoing messages, and some session state to
 170  * ensure that we can preserve the lossless, ordered delivery of
 171  * messages in the case of a TCP disconnect.
 172  */
 173 struct ceph_connection {
 174         void *private;
 175
 176         const struct ceph_connection_operations *ops;
 177
 178         struct ceph_messenger *msgr;
 179
 180         atomic_t sock_state;
 181         struct socket *sock;
 182         struct ceph_entity_addr peer_addr; /* peer address */
 183         struct ceph_entity_addr peer_addr_for_me;
 184
 185         unsigned long flags;
 186         unsigned long state;
 187         const char *error_msg;  /* error message, if any */
 188
 189         struct ceph_entity_name peer_name; /* peer name */
 190
 191         unsigned peer_features;
 192         u32 connect_seq;      /* identify the most recent connection
 193                                  attempt for this connection, client */
 194         u32 peer_global_seq;  /* peer's global seq for this connection */
 195
 196         int auth_retry;       /* true if we need a newer authorizer */
 197         void *auth_reply_buf;   /* where to put the authorizer reply */
 198         int auth_reply_buf_len;
 199
 200         struct mutex mutex;
 201
 202         /* out queue */
 203         struct list_head out_queue;
 204         struct list_head out_sent;   /* sending or sent but unacked */
 205         u64 out_seq;                 /* last message queued for send */
 206
 207         u64 in_seq, in_seq_acked;  /* last message received, acked */
 208
 209         /* connection negotiation temps */
 210         char in_banner[CEPH_BANNER_MAX_LEN];
 211         struct ceph_msg_connect out_connect;
 212         struct ceph_msg_connect_reply in_reply;
 213         struct ceph_entity_addr actual_peer_addr;
 214
 215         /* message out temps */
 216         struct ceph_msg *out_msg;        /* sending message (== tail of
 217                                             out_sent) */
 218         bool out_msg_done;
 219         struct ceph_msg_pos out_msg_pos;
 220
 221         struct kvec out_kvec[8],         /* sending header/footer data */
 222                 *out_kvec_cur;
 223         int out_kvec_left;   /* kvec's left in out_kvec */
 224         int out_skip;        /* skip this many bytes */
 225         int out_kvec_bytes;  /* total bytes left */
 226         bool out_kvec_is_msg; /* kvec refers to out_msg */
 227         int out_more;        /* there is more data after the kvecs */
 228         __le64 out_temp_ack; /* for writing an ack */
 229
 230         /* message in temps */
 231         struct ceph_msg_header in_hdr;
 232         struct ceph_msg *in_msg;
 233         struct ceph_msg_pos in_msg_pos;
 234         u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
 235
 236         char in_tag;         /* protocol control byte */
 237         int in_base_pos;     /* bytes read */
 238         __le64 in_temp_ack;  /* for reading an ack */
 239
 240         struct delayed_work work;           /* send|recv work */
 241         unsigned long       delay;          /* current delay interval */
 242 };
 243
 244
 245 extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
 246 extern int ceph_parse_ips(const char *c, const char *end,
 247                           struct ceph_entity_addr *addr,
 248                           int max_count, int *count);
 249
 250
 251 extern int ceph_msgr_init(void);
 252 extern void ceph_msgr_exit(void);
 253 extern void ceph_msgr_flush(void);
 254
 255 extern void ceph_messenger_init(struct ceph_messenger *msgr,
 256                         struct ceph_entity_addr *myaddr,
 257                         u32 supported_features,
 258                         u32 required_features,
 259                         bool nocrc);
 260
 261 extern void ceph_con_init(struct ceph_connection *con, void *private,
 262                         const struct ceph_connection_operations *ops,
 263                         struct ceph_messenger *msgr);
 264 extern void ceph_con_open(struct ceph_connection *con,
 265                           __u8 entity_type, __u64 entity_num,
 266                           struct ceph_entity_addr *addr);
 267 extern bool ceph_con_opened(struct ceph_connection *con);
 268 extern void ceph_con_close(struct ceph_connection *con);
 269 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
 270
 271 extern void ceph_msg_revoke(struct ceph_msg *msg);
 272 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
 273
 274 extern void ceph_con_keepalive(struct ceph_connection *con);
 275
 276 extern void ceph_msg_data_set_pages(struct ceph_msg *msg, struct page **pages,
 277                                 size_t length, size_t alignment);
 278 extern void ceph_msg_data_set_pagelist(struct ceph_msg *msg,
 279                                 struct ceph_pagelist *pagelist);
 280 extern void ceph_msg_data_set_bio(struct ceph_msg *msg, struct bio *bio);
 281 extern void ceph_msg_data_set_trail(struct ceph_msg *msg,
 282                                 struct ceph_pagelist *trail);
 283
 284 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
 285                                      bool can_fail);
 286 extern void ceph_msg_kfree(struct ceph_msg *m);
 287
 288
 289 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
 290 {
 291         kref_get(&msg->kref);
 292         return msg;
 293 }
 294 extern void ceph_msg_last_put(struct kref *kref);
 295 static inline void ceph_msg_put(struct ceph_msg *msg)
 296 {
 297         kref_put(&msg->kref, ceph_msg_last_put);
 298 }
 299
 300 extern void ceph_msg_dump(struct ceph_msg *msg);
 301
 302 #endif