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 /*
  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 #ifdef CONFIG_BLOCK
  87         struct bio  *bio;               /* instead of pages/pagelist */
  88         struct bio  *bio_iter;          /* bio iterator */
  89         int bio_seg;                    /* current bio segment */
  90 #endif /* CONFIG_BLOCK */
  91         struct ceph_pagelist *trail;    /* the trailing part of the data */
  92         bool front_is_vmalloc;
  93         bool more_to_follow;
  94         bool needs_out_seq;
  95         int front_max;
  96         unsigned long ack_stamp;        /* tx: when we were acked */
  97
  98         struct ceph_msgpool *pool;
  99 };
 100
 101 struct ceph_msg_pos {
 102         int page, page_pos;  /* which page; offset in page */
 103         int data_pos;        /* offset in data payload */
 104         bool 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  * A single connection with another host.
 113  *
 114  * We maintain a queue of outgoing messages, and some session state to
 115  * ensure that we can preserve the lossless, ordered delivery of
 116  * messages in the case of a TCP disconnect.
 117  */
 118 struct ceph_connection {
 119         void *private;
 120
 121         const struct ceph_connection_operations *ops;
 122
 123         struct ceph_messenger *msgr;
 124
 125         atomic_t sock_state;
 126         struct socket *sock;
 127         struct ceph_entity_addr peer_addr; /* peer address */
 128         struct ceph_entity_addr peer_addr_for_me;
 129
 130         unsigned long flags;
 131         unsigned long state;
 132         const char *error_msg;  /* error message, if any */
 133
 134         struct ceph_entity_name peer_name; /* peer name */
 135
 136         unsigned peer_features;
 137         u32 connect_seq;      /* identify the most recent connection
 138                                  attempt for this connection, client */
 139         u32 peer_global_seq;  /* peer's global seq for this connection */
 140
 141         int auth_retry;       /* true if we need a newer authorizer */
 142         void *auth_reply_buf;   /* where to put the authorizer reply */
 143         int auth_reply_buf_len;
 144
 145         struct mutex mutex;
 146
 147         /* out queue */
 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
 152         u64 in_seq, in_seq_acked;  /* last message received, acked */
 153
 154         /* connection negotiation temps */
 155         char in_banner[CEPH_BANNER_MAX_LEN];
 156         struct ceph_msg_connect out_connect;
 157         struct ceph_msg_connect_reply in_reply;
 158         struct ceph_entity_addr actual_peer_addr;
 159
 160         /* message out temps */
 161         struct ceph_msg *out_msg;        /* sending message (== tail of
 162                                             out_sent) */
 163         bool out_msg_done;
 164         struct ceph_msg_pos out_msg_pos;
 165
 166         struct kvec out_kvec[8],         /* sending header/footer data */
 167                 *out_kvec_cur;
 168         int out_kvec_left;   /* kvec's left in out_kvec */
 169         int out_skip;        /* skip this many bytes */
 170         int out_kvec_bytes;  /* total bytes left */
 171         bool out_kvec_is_msg; /* kvec refers to out_msg */
 172         int out_more;        /* there is more data after the kvecs */
 173         __le64 out_temp_ack; /* for writing an ack */
 174
 175         /* message in temps */
 176         struct ceph_msg_header in_hdr;
 177         struct ceph_msg *in_msg;
 178         struct ceph_msg_pos in_msg_pos;
 179         u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
 180
 181         char in_tag;         /* protocol control byte */
 182         int in_base_pos;     /* bytes read */
 183         __le64 in_temp_ack;  /* for reading an ack */
 184
 185         struct delayed_work work;           /* send|recv work */
 186         unsigned long       delay;          /* current delay interval */
 187 };
 188
 189
 190 extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
 191 extern int ceph_parse_ips(const char *c, const char *end,
 192                           struct ceph_entity_addr *addr,
 193                           int max_count, int *count);
 194
 195
 196 extern int ceph_msgr_init(void);
 197 extern void ceph_msgr_exit(void);
 198 extern void ceph_msgr_flush(void);
 199
 200 extern void ceph_messenger_init(struct ceph_messenger *msgr,
 201                         struct ceph_entity_addr *myaddr,
 202                         u32 supported_features,
 203                         u32 required_features,
 204                         bool nocrc);
 205
 206 extern void ceph_con_init(struct ceph_connection *con, void *private,
 207                         const struct ceph_connection_operations *ops,
 208                         struct ceph_messenger *msgr);
 209 extern void ceph_con_open(struct ceph_connection *con,
 210                           __u8 entity_type, __u64 entity_num,
 211                           struct ceph_entity_addr *addr);
 212 extern bool ceph_con_opened(struct ceph_connection *con);
 213 extern void ceph_con_close(struct ceph_connection *con);
 214 extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
 215
 216 extern void ceph_msg_revoke(struct ceph_msg *msg);
 217 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
 218
 219 extern void ceph_con_keepalive(struct ceph_connection *con);
 220
 221 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
 222                                      bool can_fail);
 223 extern void ceph_msg_kfree(struct ceph_msg *m);
 224
 225
 226 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
 227 {
 228         kref_get(&msg->kref);
 229         return msg;
 230 }
 231 extern void ceph_msg_last_put(struct kref *kref);
 232 static inline void ceph_msg_put(struct ceph_msg *msg)
 233 {
 234         kref_put(&msg->kref, ceph_msg_last_put);
 235 }
 236
 237 extern void ceph_msg_dump(struct ceph_msg *msg);
 238
 239 #endif