LXR linux/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/version.h>
  10#include <linux/workqueue.h>
  11
  12#include "types.h"
  13#include "buffer.h"
  14
  15struct ceph_msg;
  16struct ceph_connection;
  17
  18extern struct workqueue_struct *ceph_msgr_wq;       /* receive work queue */
  19
  20/*
  21 * Ceph defines these callbacks for handling connection events.
  22 */
  23struct ceph_connection_operations {
  24        struct ceph_connection *(*get)(struct ceph_connection *);
  25        void (*put)(struct ceph_connection *);
  26
  27        /* handle an incoming message. */
  28        void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
  29
  30        /* authorize an outgoing connection */
  31        int (*get_authorizer) (struct ceph_connection *con,
  32                               void **buf, int *len, int *proto,
  33                               void **reply_buf, int *reply_len, int force_new);
  34        int (*verify_authorizer_reply) (struct ceph_connection *con, int len);
  35        int (*invalidate_authorizer)(struct ceph_connection *con);
  36
  37        /* protocol version mismatch */
  38        void (*bad_proto) (struct ceph_connection *con);
  39
  40        /* there was some error on the socket (disconnect, whatever) */
  41        void (*fault) (struct ceph_connection *con);
  42
  43        /* a remote host as terminated a message exchange session, and messages
  44         * we sent (or they tried to send us) may be lost. */
  45        void (*peer_reset) (struct ceph_connection *con);
  46
  47        struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
  48                                        struct ceph_msg_header *hdr,
  49                                        int *skip);
  50};
  51
  52/* use format string %s%d */
  53#define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
  54
  55struct ceph_messenger {
  56        struct ceph_entity_inst inst;    /* my name+address */
  57        struct ceph_entity_addr my_enc_addr;
  58        struct page *zero_page;          /* used in certain error cases */
  59
  60        bool nocrc;
  61
  62        /*
  63         * the global_seq counts connections i (attempt to) initiate
  64         * in order to disambiguate certain connect race conditions.
  65         */
  66        u32 global_seq;
  67        spinlock_t global_seq_lock;
  68
  69        u32 supported_features;
  70        u32 required_features;
  71};
  72
  73/*
  74 * a single message.  it contains a header (src, dest, message type, etc.),
  75 * footer (crc values, mainly), a "front" message body, and possibly a
  76 * data payload (stored in some number of pages).
  77 */
  78struct ceph_msg {
  79        struct ceph_msg_header hdr;     /* header */
  80        struct ceph_msg_footer footer;  /* footer */
  81        struct kvec front;              /* unaligned blobs of message */
  82        struct ceph_buffer *middle;
  83        struct page **pages;            /* data payload.  NOT OWNER. */
  84        unsigned nr_pages;              /* size of page array */
  85        unsigned page_alignment;        /* io offset in first page */
  86        struct ceph_pagelist *pagelist; /* instead of pages */
  87        struct list_head list_head;
  88        struct kref kref;
  89        struct bio  *bio;               /* instead of pages/pagelist */
  90        struct bio  *bio_iter;          /* bio iterator */
  91        int bio_seg;                    /* current bio segment */
  92        struct ceph_pagelist *trail;    /* the trailing part of the data */
  93        bool front_is_vmalloc;
  94        bool more_to_follow;
  95        bool needs_out_seq;
  96        int front_max;
  97
  98        struct ceph_msgpool *pool;
  99};
 100
 101struct ceph_msg_pos {
 102        int page, page_pos;  /* which page; offset in page */
 103        int data_pos;        /* offset in data payload */
 104        int did_page_crc;    /* true if we've calculated crc for current page */
 105};
 106
 107/* ceph connection fault delay defaults, for exponential backoff */
 108#define BASE_DELAY_INTERVAL     (HZ/2)
 109#define MAX_DELAY_INTERVAL      (5 * 60 * HZ)
 110
 111/*
 112 * ceph_connection state bit flags
 113 */
 114#define LOSSYTX         0  /* we can close channel or drop messages on errors */
 115#define CONNECTING      1
 116#define NEGOTIATING     2
 117#define KEEPALIVE_PENDING      3
 118#define WRITE_PENDING   4  /* we have data ready to send */
 119#define STANDBY         8  /* no outgoing messages, socket closed.  we keep
 120                            * the ceph_connection around to maintain shared
 121                            * state with the peer. */
 122#define CLOSED          10 /* we've closed the connection */
 123#define SOCK_CLOSED     11 /* socket state changed to closed */
 124#define OPENING         13 /* open connection w/ (possibly new) peer */
 125#define DEAD            14 /* dead, about to kfree */
 126#define BACKOFF         15
 127
 128/*
 129 * A single connection with another host.
 130 *
 131 * We maintain a queue of outgoing messages, and some session state to
 132 * ensure that we can preserve the lossless, ordered delivery of
 133 * messages in the case of a TCP disconnect.
 134 */
 135struct ceph_connection {
 136        void *private;
 137        atomic_t nref;
 138
 139        const struct ceph_connection_operations *ops;
 140
 141        struct ceph_messenger *msgr;
 142        struct socket *sock;
 143        unsigned long state;    /* connection state (see flags above) */
 144        const char *error_msg;  /* error message, if any */
 145
 146        struct ceph_entity_addr peer_addr; /* peer address */
 147        struct ceph_entity_name peer_name; /* peer name */
 148        struct ceph_entity_addr peer_addr_for_me;
 149        unsigned peer_features;
 150        u32 connect_seq;      /* identify the most recent connection
 151                                 attempt for this connection, client */
 152        u32 peer_global_seq;  /* peer's global seq for this connection */
 153
 154        int auth_retry;       /* true if we need a newer authorizer */
 155        void *auth_reply_buf;   /* where to put the authorizer reply */
 156        int auth_reply_buf_len;
 157
 158        struct mutex mutex;
 159
 160        /* out queue */
 161        struct list_head out_queue;
 162        struct list_head out_sent;   /* sending or sent but unacked */
 163        u64 out_seq;                 /* last message queued for send */
 164
 165        u64 in_seq, in_seq_acked;  /* last message received, acked */
 166
 167        /* connection negotiation temps */
 168        char in_banner[CEPH_BANNER_MAX_LEN];
 169        union {
 170                struct {  /* outgoing connection */
 171                        struct ceph_msg_connect out_connect;
 172                        struct ceph_msg_connect_reply in_reply;
 173                };
 174                struct {  /* incoming */
 175                        struct ceph_msg_connect in_connect;
 176                        struct ceph_msg_connect_reply out_reply;
 177                };
 178        };
 179        struct ceph_entity_addr actual_peer_addr;
 180
 181        /* message out temps */
 182        struct ceph_msg *out_msg;        /* sending message (== tail of
 183                                            out_sent) */
 184        bool out_msg_done;
 185        struct ceph_msg_pos out_msg_pos;
 186
 187        struct kvec out_kvec[8],         /* sending header/footer data */
 188                *out_kvec_cur;
 189        int out_kvec_left;   /* kvec's left in out_kvec */
 190        int out_skip;        /* skip this many bytes */
 191        int out_kvec_bytes;  /* total bytes left */
 192        bool out_kvec_is_msg; /* kvec refers to out_msg */
 193        int out_more;        /* there is more data after the kvecs */
 194        __le64 out_temp_ack; /* for writing an ack */
 195
 196        /* message in temps */
 197        struct ceph_msg_header in_hdr;
 198        struct ceph_msg *in_msg;
 199        struct ceph_msg_pos in_msg_pos;
 200        u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
 201
 202        char in_tag;         /* protocol control byte */
 203        int in_base_pos;     /* bytes read */
 204        __le64 in_temp_ack;  /* for reading an ack */
 205
 206        struct delayed_work work;           /* send|recv work */
 207        unsigned long       delay;          /* current delay interval */
 208};
 209
 210
 211extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
 212extern int ceph_parse_ips(const char *c, const char *end,
 213                          struct ceph_entity_addr *addr,
 214                          int max_count, int *count);
 215
 216
 217extern int ceph_msgr_init(void);
 218extern void ceph_msgr_exit(void);
 219extern void ceph_msgr_flush(void);
 220
 221extern struct ceph_messenger *ceph_messenger_create(
 222        struct ceph_entity_addr *myaddr,
 223        u32 features, u32 required);
 224extern void ceph_messenger_destroy(struct ceph_messenger *);
 225
 226extern void ceph_con_init(struct ceph_messenger *msgr,
 227                          struct ceph_connection *con);
 228extern void ceph_con_open(struct ceph_connection *con,
 229                          struct ceph_entity_addr *addr);
 230extern bool ceph_con_opened(struct ceph_connection *con);
 231extern void ceph_con_close(struct ceph_connection *con);
 232extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
 233extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
 234extern void ceph_con_revoke_message(struct ceph_connection *con,
 235                                  struct ceph_msg *msg);
 236extern void ceph_con_keepalive(struct ceph_connection *con);
 237extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
 238extern void ceph_con_put(struct ceph_connection *con);
 239
 240extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags);
 241extern void ceph_msg_kfree(struct ceph_msg *m);
 242
 243
 244static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
 245{
 246        kref_get(&msg->kref);
 247        return msg;
 248}
 249extern void ceph_msg_last_put(struct kref *kref);
 250static inline void ceph_msg_put(struct ceph_msg *msg)
 251{
 252        kref_put(&msg->kref, ceph_msg_last_put);
 253}
 254
 255extern void ceph_msg_dump(struct ceph_msg *msg);
 256
 257#endif
 258