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