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/sunrpc/sched.h>
  16 #include <linux/sunrpc/xdr.h>
  17
  18 extern unsigned int xprt_udp_slot_table_entries;
  19 extern unsigned int xprt_tcp_slot_table_entries;
  20
  21 #define RPC_MIN_SLOT_TABLE      (2U)
  22 #define RPC_DEF_SLOT_TABLE      (16U)
  23 #define RPC_MAX_SLOT_TABLE      (128U)
  24
  25 /*
  26  * RPC call and reply header size as number of 32bit words (verifier
  27  * size computed separately)
  28  */
  29 #define RPC_CALLHDRSIZE         6
  30 #define RPC_REPHDRSIZE          4
  31
  32 /*
  33  * Parameters for choosing a free port
  34  */
  35 extern unsigned int xprt_min_resvport;
  36 extern unsigned int xprt_max_resvport;
  37
  38 #define RPC_MIN_RESVPORT        (1U)
  39 #define RPC_MAX_RESVPORT        (65535U)
  40 #define RPC_DEF_MIN_RESVPORT    (650U)
  41 #define RPC_DEF_MAX_RESVPORT    (1023U)
  42
  43 /*
  44  * This describes a timeout strategy
  45  */
  46 struct rpc_timeout {
  47         unsigned long           to_initval,             /* initial timeout */
  48                                 to_maxval,              /* max timeout */
  49                                 to_increment;           /* if !exponential */
  50         unsigned int            to_retries;             /* max # of retries */
  51         unsigned char           to_exponential;
  52 };
  53
  54 struct rpc_task;
  55 struct rpc_xprt;
  56 struct seq_file;
  57
  58 /*
  59  * This describes a complete RPC request
  60  */
  61 struct rpc_rqst {
  62         /*
  63          * This is the user-visible part
  64          */
  65         struct rpc_xprt *       rq_xprt;                /* RPC client */
  66         struct xdr_buf          rq_snd_buf;             /* send buffer */
  67         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
  68
  69         /*
  70          * This is the private part
  71          */
  72         struct rpc_task *       rq_task;        /* RPC task data */
  73         __u32                   rq_xid;         /* request XID */
  74         int                     rq_cong;        /* has incremented xprt->cong */
  75         int                     rq_received;    /* receive completed */
  76         u32                     rq_seqno;       /* gss seq no. used on req. */
  77         int                     rq_enc_pages_num;
  78         struct page             **rq_enc_pages; /* scratch pages for use by
  79                                                    gss privacy code */
  80         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
  81         struct list_head        rq_list;
  82
  83         __u32 *                 rq_buffer;      /* XDR encode buffer */
  84         size_t                  rq_bufsize;
  85
  86         struct xdr_buf          rq_private_buf;         /* The receive buffer
  87                                                          * used in the softirq.
  88                                                          */
  89         unsigned long           rq_majortimeo;  /* major timeout alarm */
  90         unsigned long           rq_timeout;     /* Current timeout value */
  91         unsigned int            rq_retries;     /* # of retries */
  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            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
 109         void            (*connect)(struct rpc_task *task);
 110         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 111         void            (*buf_free)(struct rpc_task *task);
 112         int             (*send_request)(struct rpc_task *task);
 113         void            (*set_retrans_timeout)(struct rpc_task *task);
 114         void            (*timer)(struct rpc_task *task);
 115         void            (*release_request)(struct rpc_task *task);
 116         void            (*close)(struct rpc_xprt *xprt);
 117         void            (*destroy)(struct rpc_xprt *xprt);
 118         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 119 };
 120
 121 struct rpc_xprt {
 122         struct rpc_xprt_ops *   ops;            /* transport methods */
 123         struct socket *         sock;           /* BSD socket layer */
 124         struct sock *           inet;           /* INET layer */
 125
 126         struct rpc_timeout      timeout;        /* timeout parms */
 127         struct sockaddr_in      addr;           /* server address */
 128         int                     prot;           /* IP protocol */
 129
 130         unsigned long           cong;           /* current congestion */
 131         unsigned long           cwnd;           /* congestion window */
 132
 133         size_t                  rcvsize,        /* transport rcv buffer size */
 134                                 sndsize;        /* transport send buffer size */
 135
 136         size_t                  max_payload;    /* largest RPC payload size,
 137                                                    in bytes */
 138         unsigned int            tsh_size;       /* size of transport specific
 139                                                    header */
 140
 141         struct rpc_wait_queue   sending;        /* requests waiting to send */
 142         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 143         struct rpc_wait_queue   pending;        /* requests in flight */
 144         struct rpc_wait_queue   backlog;        /* waiting for slot */
 145         struct list_head        free;           /* free slots */
 146         struct rpc_rqst *       slot;           /* slot table storage */
 147         unsigned int            max_reqs;       /* total slots */
 148         unsigned long           state;          /* transport state */
 149         unsigned char           shutdown   : 1, /* being shut down */
 150                                 resvport   : 1; /* use a reserved port */
 151
 152         /*
 153          * XID
 154          */
 155         __u32                   xid;            /* Next XID value to use */
 156
 157         /*
 158          * State of TCP reply receive stuff
 159          */
 160         u32                     tcp_recm,       /* Fragment header */
 161                                 tcp_xid,        /* Current XID */
 162                                 tcp_reclen,     /* fragment length */
 163                                 tcp_offset;     /* fragment offset */
 164         unsigned long           tcp_copied,     /* copied to request */
 165                                 tcp_flags;
 166         /*
 167          * Connection of transports
 168          */
 169         unsigned long           connect_timeout,
 170                                 bind_timeout,
 171                                 reestablish_timeout;
 172         struct work_struct      connect_worker;
 173         unsigned short          port;
 174
 175         /*
 176          * Disconnection of idle transports
 177          */
 178         struct work_struct      task_cleanup;
 179         struct timer_list       timer;
 180         unsigned long           last_used,
 181                                 idle_timeout;
 182
 183         /*
 184          * Send stuff
 185          */
 186         spinlock_t              transport_lock; /* lock transport info */
 187         spinlock_t              reserve_lock;   /* lock slot table */
 188         struct rpc_task *       snd_task;       /* Task blocked in send */
 189
 190         struct list_head        recv;
 191
 192         struct {
 193                 unsigned long           bind_count,     /* total number of binds */
 194                                         connect_count,  /* total number of connects */
 195                                         connect_start,  /* connect start timestamp */
 196                                         connect_time,   /* jiffies waiting for connect */
 197                                         sends,          /* how many complete requests */
 198                                         recvs,          /* how many complete requests */
 199                                         bad_xids;       /* lookup_rqst didn't find XID */
 200
 201                 unsigned long long      req_u,          /* average requests on the wire */
 202                                         bklog_u;        /* backlog queue utilization */
 203         } stat;
 204
 205         void                    (*old_data_ready)(struct sock *, int);
 206         void                    (*old_state_change)(struct sock *);
 207         void                    (*old_write_space)(struct sock *);
 208 };
 209
 210 #define XPRT_LAST_FRAG          (1 << 0)
 211 #define XPRT_COPY_RECM          (1 << 1)
 212 #define XPRT_COPY_XID           (1 << 2)
 213 #define XPRT_COPY_DATA          (1 << 3)
 214
 215 #ifdef __KERNEL__
 216
 217 /*
 218  * Transport operations used by ULPs
 219  */
 220 struct rpc_xprt *       xprt_create_proto(int proto, struct sockaddr_in *addr, struct rpc_timeout *to);
 221 void                    xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr);
 222
 223 /*
 224  * Generic internal transport functions
 225  */
 226 void                    xprt_connect(struct rpc_task *task);
 227 void                    xprt_reserve(struct rpc_task *task);
 228 int                     xprt_reserve_xprt(struct rpc_task *task);
 229 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 230 int                     xprt_prepare_transmit(struct rpc_task *task);
 231 void                    xprt_transmit(struct rpc_task *task);
 232 void                    xprt_abort_transmit(struct rpc_task *task);
 233 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 234 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 235 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 236 void                    xprt_release(struct rpc_task *task);
 237 int                     xprt_destroy(struct rpc_xprt *xprt);
 238
 239 static inline u32 *xprt_skip_transport_header(struct rpc_xprt *xprt, u32 *p)
 240 {
 241         return p + xprt->tsh_size;
 242 }
 243
 244 /*
 245  * Transport switch helper functions
 246  */
 247 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 248 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 249 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 250 void                    xprt_wait_for_buffer_space(struct rpc_task *task);
 251 void                    xprt_write_space(struct rpc_xprt *xprt);
 252 void                    xprt_update_rtt(struct rpc_task *task);
 253 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 254 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid);
 255 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 256 void                    xprt_release_rqst_cong(struct rpc_task *task);
 257 void                    xprt_disconnect(struct rpc_xprt *xprt);
 258
 259 /*
 260  * Socket transport setup operations
 261  */
 262 int                     xs_setup_udp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 263 int                     xs_setup_tcp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 264
 265 /*
 266  * Reserved bit positions in xprt->state
 267  */
 268 #define XPRT_LOCKED             (0)
 269 #define XPRT_CONNECTED          (1)
 270 #define XPRT_CONNECTING         (2)
 271 #define XPRT_CLOSE_WAIT         (3)
 272
 273 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 274 {
 275         set_bit(XPRT_CONNECTED, &xprt->state);
 276 }
 277
 278 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 279 {
 280         clear_bit(XPRT_CONNECTED, &xprt->state);
 281 }
 282
 283 static inline int xprt_connected(struct rpc_xprt *xprt)
 284 {
 285         return test_bit(XPRT_CONNECTED, &xprt->state);
 286 }
 287
 288 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 289 {
 290         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 291 }
 292
 293 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 294 {
 295         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 296 }
 297
 298 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 299 {
 300         smp_mb__before_clear_bit();
 301         clear_bit(XPRT_CONNECTING, &xprt->state);
 302         smp_mb__after_clear_bit();
 303 }
 304
 305 static inline int xprt_connecting(struct rpc_xprt *xprt)
 306 {
 307         return test_bit(XPRT_CONNECTING, &xprt->state);
 308 }
 309
 310 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 311 {
 312         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 313 }
 314
 315 #endif /* __KERNEL__*/
 316
 317 #endif /* _LINUX_SUNRPC_XPRT_H */