include/linux/sunrpc/xprt.h

   1 /*
   2  *  linux/include/linux/sunrpc/xprt.h
   3  *
   4  *  Declarations for the RPC transport interface.
   5  *
   6  *  Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #ifndef _LINUX_SUNRPC_XPRT_H
  10 #define _LINUX_SUNRPC_XPRT_H
  11
  12 #include <linux/uio.h>
  13 #include <linux/socket.h>
  14 #include <linux/in.h>
  15 #include <linux/kref.h>
  16 #include <linux/sunrpc/sched.h>
  17 #include <linux/sunrpc/xdr.h>
  18 #include <linux/sunrpc/msg_prot.h>
  19
  20 #ifdef __KERNEL__
  21
  22 extern unsigned int xprt_udp_slot_table_entries;
  23 extern unsigned int xprt_tcp_slot_table_entries;
  24
  25 #define RPC_MIN_SLOT_TABLE      (2U)
  26 #define RPC_DEF_SLOT_TABLE      (16U)
  27 #define RPC_MAX_SLOT_TABLE      (128U)
  28
  29 /*
  30  * Parameters for choosing a free port
  31  */
  32 extern unsigned int xprt_min_resvport;
  33 extern unsigned int xprt_max_resvport;
  34
  35 #define RPC_MIN_RESVPORT        (1U)
  36 #define RPC_MAX_RESVPORT        (65535U)
  37 #define RPC_DEF_MIN_RESVPORT    (665U)
  38 #define RPC_DEF_MAX_RESVPORT    (1023U)
  39
  40 /*
  41  * This describes a timeout strategy
  42  */
  43 struct rpc_timeout {
  44         unsigned long           to_initval,             /* initial timeout */
  45                                 to_maxval,              /* max timeout */
  46                                 to_increment;           /* if !exponential */
  47         unsigned int            to_retries;             /* max # of retries */
  48         unsigned char           to_exponential;
  49 };
  50
  51 enum rpc_display_format_t {
  52         RPC_DISPLAY_ADDR = 0,
  53         RPC_DISPLAY_PORT,
  54         RPC_DISPLAY_PROTO,
  55         RPC_DISPLAY_ALL,
  56         RPC_DISPLAY_HEX_ADDR,
  57         RPC_DISPLAY_HEX_PORT,
  58         RPC_DISPLAY_UNIVERSAL_ADDR,
  59         RPC_DISPLAY_NETID,
  60         RPC_DISPLAY_MAX,
  61 };
  62
  63 struct rpc_task;
  64 struct rpc_xprt;
  65 struct seq_file;
  66
  67 /*
  68  * This describes a complete RPC request
  69  */
  70 struct rpc_rqst {
  71         /*
  72          * This is the user-visible part
  73          */
  74         struct rpc_xprt *       rq_xprt;                /* RPC client */
  75         struct xdr_buf          rq_snd_buf;             /* send buffer */
  76         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
  77
  78         /*
  79          * This is the private part
  80          */
  81         struct rpc_task *       rq_task;        /* RPC task data */
  82         __be32                  rq_xid;         /* request XID */
  83         int                     rq_cong;        /* has incremented xprt->cong */
  84         int                     rq_received;    /* receive completed */
  85         u32                     rq_seqno;       /* gss seq no. used on req. */
  86         int                     rq_enc_pages_num;
  87         struct page             **rq_enc_pages; /* scratch pages for use by
  88                                                    gss privacy code */
  89         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
  90         struct list_head        rq_list;
  91
  92         __u32 *                 rq_buffer;      /* XDR encode buffer */
  93         size_t                  rq_bufsize,
  94                                 rq_callsize,
  95                                 rq_rcvsize;
  96
  97         struct xdr_buf          rq_private_buf;         /* The receive buffer
  98                                                          * used in the softirq.
  99                                                          */
 100         unsigned long           rq_majortimeo;  /* major timeout alarm */
 101         unsigned long           rq_timeout;     /* Current timeout value */
 102         unsigned int            rq_retries;     /* # of retries */
 103
 104         /*
 105          * Partial send handling
 106          */
 107         u32                     rq_bytes_sent;  /* Bytes we have sent */
 108
 109         unsigned long           rq_xtime;       /* when transmitted */
 110         int                     rq_ntrans;
 111 };
 112 #define rq_svec                 rq_snd_buf.head
 113 #define rq_slen                 rq_snd_buf.len
 114
 115 struct rpc_xprt_ops {
 116         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
 117         int             (*reserve_xprt)(struct rpc_task *task);
 118         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 119         void            (*rpcbind)(struct rpc_task *task);
 120         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
 121         void            (*connect)(struct rpc_task *task);
 122         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 123         void            (*buf_free)(void *buffer);
 124         int             (*send_request)(struct rpc_task *task);
 125         void            (*set_retrans_timeout)(struct rpc_task *task);
 126         void            (*timer)(struct rpc_task *task);
 127         void            (*release_request)(struct rpc_task *task);
 128         void            (*close)(struct rpc_xprt *xprt);
 129         void            (*destroy)(struct rpc_xprt *xprt);
 130         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 131 };
 132
 133 struct rpc_xprt {
 134         struct kref             kref;           /* Reference count */
 135         struct rpc_xprt_ops *   ops;            /* transport methods */
 136
 137         struct rpc_timeout      timeout;        /* timeout parms */
 138         struct sockaddr_storage addr;           /* server address */
 139         size_t                  addrlen;        /* size of server address */
 140         int                     prot;           /* IP protocol */
 141
 142         unsigned long           cong;           /* current congestion */
 143         unsigned long           cwnd;           /* congestion window */
 144
 145         size_t                  max_payload;    /* largest RPC payload size,
 146                                                    in bytes */
 147         unsigned int            tsh_size;       /* size of transport specific
 148                                                    header */
 149
 150         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
 151         struct rpc_wait_queue   sending;        /* requests waiting to send */
 152         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 153         struct rpc_wait_queue   pending;        /* requests in flight */
 154         struct rpc_wait_queue   backlog;        /* waiting for slot */
 155         struct list_head        free;           /* free slots */
 156         struct rpc_rqst *       slot;           /* slot table storage */
 157         unsigned int            max_reqs;       /* total slots */
 158         unsigned long           state;          /* transport state */
 159         unsigned char           shutdown   : 1, /* being shut down */
 160                                 resvport   : 1; /* use a reserved port */
 161         unsigned int            bind_index;     /* bind function index */
 162
 163         /*
 164          * Connection of transports
 165          */
 166         unsigned long           connect_timeout,
 167                                 bind_timeout,
 168                                 reestablish_timeout;
 169
 170         /*
 171          * Disconnection of idle transports
 172          */
 173         struct work_struct      task_cleanup;
 174         struct timer_list       timer;
 175         unsigned long           last_used,
 176                                 idle_timeout;
 177
 178         /*
 179          * Send stuff
 180          */
 181         spinlock_t              transport_lock; /* lock transport info */
 182         spinlock_t              reserve_lock;   /* lock slot table */
 183         u32                     xid;            /* Next XID value to use */
 184         struct rpc_task *       snd_task;       /* Task blocked in send */
 185         struct list_head        recv;
 186
 187         struct {
 188                 unsigned long           bind_count,     /* total number of binds */
 189                                         connect_count,  /* total number of connects */
 190                                         connect_start,  /* connect start timestamp */
 191                                         connect_time,   /* jiffies waiting for connect */
 192                                         sends,          /* how many complete requests */
 193                                         recvs,          /* how many complete requests */
 194                                         bad_xids;       /* lookup_rqst didn't find XID */
 195
 196                 unsigned long long      req_u,          /* average requests on the wire */
 197                                         bklog_u;        /* backlog queue utilization */
 198         } stat;
 199
 200         char *                  address_strings[RPC_DISPLAY_MAX];
 201 };
 202
 203 struct rpc_xprtsock_create {
 204         int                     proto;          /* IPPROTO_UDP or IPPROTO_TCP */
 205         struct sockaddr *       srcaddr;        /* optional local address */
 206         struct sockaddr *       dstaddr;        /* remote peer address */
 207         size_t                  addrlen;
 208         struct rpc_timeout *    timeout;        /* optional timeout parameters */
 209 };
 210
 211 struct xprt_class {
 212         struct list_head        list;
 213         unsigned short          family;
 214         int                     protocol;
 215         struct rpc_xprt *       (*setup)(struct rpc_xprtsock_create *);
 216         struct module           *owner;
 217         char                    name[32];
 218 };
 219
 220 /*
 221  * Transport operations used by ULPs
 222  */
 223 void                    xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr);
 224
 225 /*
 226  * Generic internal transport functions
 227  */
 228 struct rpc_xprt *       xprt_create_transport(struct rpc_xprtsock_create *args);
 229 void                    xprt_connect(struct rpc_task *task);
 230 void                    xprt_reserve(struct rpc_task *task);
 231 int                     xprt_reserve_xprt(struct rpc_task *task);
 232 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 233 int                     xprt_prepare_transmit(struct rpc_task *task);
 234 void                    xprt_transmit(struct rpc_task *task);
 235 void                    xprt_end_transmit(struct rpc_task *task);
 236 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 237 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 238 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 239 void                    xprt_release(struct rpc_task *task);
 240 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
 241 void                    xprt_put(struct rpc_xprt *xprt);
 242
 243 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
 244 {
 245         return p + xprt->tsh_size;
 246 }
 247
 248 /*
 249  * Transport switch helper functions
 250  */
 251 int                     xprt_register_transport(struct xprt_class *type);
 252 int                     xprt_unregister_transport(struct xprt_class *type);
 253 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 254 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 255 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 256 void                    xprt_wait_for_buffer_space(struct rpc_task *task);
 257 void                    xprt_write_space(struct rpc_xprt *xprt);
 258 void                    xprt_update_rtt(struct rpc_task *task);
 259 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 260 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
 261 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 262 void                    xprt_release_rqst_cong(struct rpc_task *task);
 263 void                    xprt_disconnect(struct rpc_xprt *xprt);
 264
 265 /*
 266  * Socket transport setup operations
 267  */
 268 struct rpc_xprt *       xs_setup_udp(struct rpc_xprtsock_create *args);
 269 struct rpc_xprt *       xs_setup_tcp(struct rpc_xprtsock_create *args);
 270 int                     init_socket_xprt(void);
 271 void                    cleanup_socket_xprt(void);
 272
 273 /*
 274  * Reserved bit positions in xprt->state
 275  */
 276 #define XPRT_LOCKED             (0)
 277 #define XPRT_CONNECTED          (1)
 278 #define XPRT_CONNECTING         (2)
 279 #define XPRT_CLOSE_WAIT         (3)
 280 #define XPRT_BOUND              (4)
 281 #define XPRT_BINDING            (5)
 282
 283 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 284 {
 285         set_bit(XPRT_CONNECTED, &xprt->state);
 286 }
 287
 288 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 289 {
 290         clear_bit(XPRT_CONNECTED, &xprt->state);
 291 }
 292
 293 static inline int xprt_connected(struct rpc_xprt *xprt)
 294 {
 295         return test_bit(XPRT_CONNECTED, &xprt->state);
 296 }
 297
 298 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 299 {
 300         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 301 }
 302
 303 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 304 {
 305         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 306 }
 307
 308 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 309 {
 310         smp_mb__before_clear_bit();
 311         clear_bit(XPRT_CONNECTING, &xprt->state);
 312         smp_mb__after_clear_bit();
 313 }
 314
 315 static inline int xprt_connecting(struct rpc_xprt *xprt)
 316 {
 317         return test_bit(XPRT_CONNECTING, &xprt->state);
 318 }
 319
 320 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 321 {
 322         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 323 }
 324
 325 static inline void xprt_set_bound(struct rpc_xprt *xprt)
 326 {
 327         test_and_set_bit(XPRT_BOUND, &xprt->state);
 328 }
 329
 330 static inline int xprt_bound(struct rpc_xprt *xprt)
 331 {
 332         return test_bit(XPRT_BOUND, &xprt->state);
 333 }
 334
 335 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
 336 {
 337         clear_bit(XPRT_BOUND, &xprt->state);
 338 }
 339
 340 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
 341 {
 342         smp_mb__before_clear_bit();
 343         clear_bit(XPRT_BINDING, &xprt->state);
 344         smp_mb__after_clear_bit();
 345 }
 346
 347 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 348 {
 349         return test_and_set_bit(XPRT_BINDING, &xprt->state);
 350 }
 351
 352 #endif /* __KERNEL__*/
 353
 354 #endif /* _LINUX_SUNRPC_XPRT_H */