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 "types.h"
  12 #include "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 /*
  68  * a single message.  it contains a header (src, dest, message type, etc.),
  69  * footer (crc values, mainly), a "front" message body, and possibly a
  70  * data payload (stored in some number of pages).
  71  */
  72 struct ceph_msg {
  73         struct ceph_msg_header hdr;     /* header */
  74         struct ceph_msg_footer footer;  /* footer */
  75         struct kvec front;              /* unaligned blobs of message */
  76         struct ceph_buffer *middle;
  77         struct page **pages;            /* data payload.  NOT OWNER. */
  78         unsigned nr_pages;              /* size of page array */
  79         unsigned page_alignment;        /* io offset in first page */
  80         struct ceph_pagelist *pagelist; /* instead of pages */
  81
  82         struct ceph_connection *con;
  83         struct list_head list_head;
  84
  85         struct kref kref;
  86         struct bio  *bio;               /* instead of pages/pagelist */
  87         struct bio  *bio_iter;          /* bio iterator */
  88         int bio_seg;                    /* current bio segment */
  89         struct ceph_pagelist *trail;    /* the trailing part of the data */
  90         bool front_is_vmalloc;
  91         bool more_to_follow;
  92         bool needs_out_seq;
  93         int front_max;
  94         unsigned long ack_stamp;        /* tx: when we were acked */
  95
  96         struct ceph_msgpool *pool;
  97 };
  98
  99 struct ceph_msg_pos {
 100         int page, page_pos;  /* which page; offset in page */
 101         int data_pos;        /* offset in data payload */
 102         bool did_page_crc;   /* true if we've calculated crc for current page */
 103 };
 104
 105 /* ceph connection fault delay defaults, for exponential backoff */
 106 #define BASE_DELAY_INTERVAL     (HZ/2)
 107 #define MAX_DELAY_INTERVAL      (5 * 60 * HZ)
 108
 109 /*
 110  * A single connection with another host.
 111  *
 112  * We maintain a queue of outgoing messages, and some session state to
 113  * ensure that we can preserve the lossless, ordered delivery of
 114  * messages in the case of a TCP disconnect.
 115  */
 116 struct ceph_connection {
 117         void *private;
 118
 119         const struct ceph_connection_operations *ops;
 120
 121         struct ceph_messenger *msgr;
 122
 123         atomic_t sock_state;
 124         struct socket *sock;
 125         struct ceph_entity_addr peer_addr; /* peer address */
 126         struct ceph_entity_addr peer_addr_for_me;
 127
 128         unsigned long flags;
 129         unsigned long state;
 130         const char *error_msg;  /* error message, if any */
 131
 132         struct ceph_entity_name peer_name; /* peer name */
 133
 134         unsigned peer_features;
 135         u32 connect_seq;      /* identify the most recent connection
 136                                  attempt for this connection, client */
 137         u32 peer_global_seq;  /* peer's global seq for this connection */
 138
 139         int auth_retry;       /* true if we need a newer authorizer */
 140         void *auth_reply_buf;   /* where to put the authorizer reply */
 141         int auth_reply_buf_len;
 142
 143         struct mutex mutex;
 144
 145         /* out queue */
 146         struct list_head out_queue;
 147         struct list_head out_sent;   /* sending or sent but unacked */
 148         u64 out_seq;                 /* last message queued for send */
 149
 150         u64 in_seq, in_seq_acked;  /* last message received, acked */
 151
 152         /* connection negotiation temps */
 153         char in_banner[CEPH_BANNER_MAX_LEN];
 154         struct ceph_msg_connect out_connect;
 155         struct ceph_msg_connect_reply in_reply;
 156         struct ceph_entity_addr actual_peer_addr;
 157
 158         /* message out temps */
 159         struct ceph_msg *out_msg;        /* sending message (== tail of
 160                                             out_sent) */
 161         bool out_msg_done;
 162         struct ceph_msg_pos out_msg_pos;
 163
 164         struct kvec out_kvec[8],         /* sending header/footer data */
 165                 *out_kvec_cur;
 166         int out_kvec_left;   /* kvec's left in out_kvec */
 167         int out_skip;        /* skip this many bytes */
 168         int out_kvec_bytes;  /* total bytes left */
 169         bool out_kvec_is_msg; /* kvec refers to out_msg */
 170         int out_more;        /* there is more data after the kvecs */
 171         __le64 out_temp_ack; /* for writing an ack */
 172
 173         /* message in temps */
 174         struct ceph_msg_header in_hdr;
 175         struct ceph_msg *in_msg;
 176         struct ceph_msg_pos in_msg_pos;
 177         u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
 178
 179         char in_tag;         /* protocol control byte */
 180         int in_base_pos;     /* bytes read */
 181         __le64 in_temp_ack;  /* for reading an ack */
 182
 183         struct delayed_work work;           /* send|recv work */
 184         unsigned long       delay;          /* current delay interval */
 185 };
 186
 187
 188 extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
 189 extern int ceph_parse_ips(const char *c, const char *end,
 190                           struct ceph_entity_addr *addr,
 191                           int max_count, int *count);
 192
 193
 194 extern int ceph_msgr_init(void);
 195 extern void ceph_msgr_exit(void);
 196 extern void ceph_msgr_flush(void);
 197
 198 extern void ceph_messenger_init(struct ceph_messenger *msgr,
 199                         struct ceph_entity_addr *myaddr,
 200                         u32 supported_features,
 201                         u32 required_features,
 202                         bool nocrc);
 203
 204 extern void ceph_con_init(struct ceph_connection *con, void *private,
 205                         const struct ceph_connection_operations *ops,
 206                         struct ceph_messenger *msgr);
 207 extern void ceph_con_open(struct ceph_connection *con,
 208                           __u8 entity_type, __u64 entity_num,
 209                           struct ceph_entity_addr *addr);
 210 extern bool ceph_con_opened(struct ceph_connection *con);
 211 extern void ceph_con_close(struct ceph_connection *con);
 212 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
 213
 214 extern void ceph_msg_revoke(struct ceph_msg *msg);
 215 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
 216
 217 extern void ceph_con_keepalive(struct ceph_connection *con);
 218
 219 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
 220                                      bool can_fail);
 221 extern void ceph_msg_kfree(struct ceph_msg *m);
 222
 223
 224 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
 225 {
 226         kref_get(&msg->kref);
 227         return msg;
 228 }
 229 extern void ceph_msg_last_put(struct kref *kref);
 230 static inline void ceph_msg_put(struct ceph_msg *msg)
 231 {
 232         kref_put(&msg->kref, ceph_msg_last_put);
 233 }
 234
 235 extern void ceph_msg_dump(struct ceph_msg *msg);
 236
 237 #endif