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 /* Default timeout values */
  26 #define RPC_MAX_UDP_TIMEOUT     (60*HZ)
  27 #define RPC_MAX_TCP_TIMEOUT     (600*HZ)
  28
  29 /*
  30  * Wait duration for an RPC TCP connection to be established.  Solaris
  31  * NFS over TCP uses 60 seconds, for example, which is in line with how
  32  * long a server takes to reboot.
  33  */
  34 #define RPC_CONNECT_TIMEOUT     (60*HZ)
  35
  36 /*
  37  * Delay an arbitrary number of seconds before attempting to reconnect
  38  * after an error.
  39  */
  40 #define RPC_REESTABLISH_TIMEOUT (15*HZ)
  41
  42 /*
  43  * RPC transport idle timeout.
  44  */
  45 #define RPC_IDLE_DISCONNECT_TIMEOUT     (5*60*HZ)
  46
  47 /*
  48  * RPC call and reply header size as number of 32bit words (verifier
  49  * size computed separately)
  50  */
  51 #define RPC_CALLHDRSIZE         6
  52 #define RPC_REPHDRSIZE          4
  53
  54 /*
  55  * Parameters for choosing a free port
  56  */
  57 extern unsigned int xprt_min_resvport;
  58 extern unsigned int xprt_max_resvport;
  59
  60 #define RPC_MIN_RESVPORT        (1U)
  61 #define RPC_MAX_RESVPORT        (65535U)
  62 #define RPC_DEF_MIN_RESVPORT    (650U)
  63 #define RPC_DEF_MAX_RESVPORT    (1023U)
  64
  65 /*
  66  * This describes a timeout strategy
  67  */
  68 struct rpc_timeout {
  69         unsigned long           to_initval,             /* initial timeout */
  70                                 to_maxval,              /* max timeout */
  71                                 to_increment;           /* if !exponential */
  72         unsigned int            to_retries;             /* max # of retries */
  73         unsigned char           to_exponential;
  74 };
  75
  76 struct rpc_task;
  77 struct rpc_xprt;
  78
  79 /*
  80  * This describes a complete RPC request
  81  */
  82 struct rpc_rqst {
  83         /*
  84          * This is the user-visible part
  85          */
  86         struct rpc_xprt *       rq_xprt;                /* RPC client */
  87         struct xdr_buf          rq_snd_buf;             /* send buffer */
  88         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
  89
  90         /*
  91          * This is the private part
  92          */
  93         struct rpc_task *       rq_task;        /* RPC task data */
  94         __u32                   rq_xid;         /* request XID */
  95         int                     rq_cong;        /* has incremented xprt->cong */
  96         int                     rq_received;    /* receive completed */
  97         u32                     rq_seqno;       /* gss seq no. used on req. */
  98
  99         struct list_head        rq_list;
 100
 101         struct xdr_buf          rq_private_buf;         /* The receive buffer
 102                                                          * used in the softirq.
 103                                                          */
 104         unsigned long           rq_majortimeo;  /* major timeout alarm */
 105         unsigned long           rq_timeout;     /* Current timeout value */
 106         unsigned int            rq_retries;     /* # of retries */
 107         /*
 108          * For authentication (e.g. auth_des)
 109          */
 110         u32                     rq_creddata[2];
 111
 112         /*
 113          * Partial send handling
 114          */
 115
 116         u32                     rq_bytes_sent;  /* Bytes we have sent */
 117
 118         unsigned long           rq_xtime;       /* when transmitted */
 119         int                     rq_ntrans;
 120 };
 121 #define rq_svec                 rq_snd_buf.head
 122 #define rq_slen                 rq_snd_buf.len
 123
 124 struct rpc_xprt_ops {
 125         void            (*set_buffer_size)(struct rpc_xprt *xprt);
 126         int             (*reserve_xprt)(struct rpc_task *task);
 127         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 128         void            (*connect)(struct rpc_task *task);
 129         int             (*send_request)(struct rpc_task *task);
 130         void            (*set_retrans_timeout)(struct rpc_task *task);
 131         void            (*timer)(struct rpc_task *task);
 132         void            (*release_request)(struct rpc_task *task);
 133         void            (*close)(struct rpc_xprt *xprt);
 134         void            (*destroy)(struct rpc_xprt *xprt);
 135 };
 136
 137 struct rpc_xprt {
 138         struct rpc_xprt_ops *   ops;            /* transport methods */
 139         struct socket *         sock;           /* BSD socket layer */
 140         struct sock *           inet;           /* INET layer */
 141
 142         struct rpc_timeout      timeout;        /* timeout parms */
 143         struct sockaddr_in      addr;           /* server address */
 144         int                     prot;           /* IP protocol */
 145
 146         unsigned long           cong;           /* current congestion */
 147         unsigned long           cwnd;           /* congestion window */
 148
 149         unsigned int            rcvsize,        /* transport rcv buffer size */
 150                                 sndsize;        /* transport send buffer size */
 151
 152         size_t                  max_payload;    /* largest RPC payload size,
 153                                                    in bytes */
 154         unsigned int            tsh_size;       /* size of transport specific
 155                                                    header */
 156
 157         struct rpc_wait_queue   sending;        /* requests waiting to send */
 158         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 159         struct rpc_wait_queue   pending;        /* requests in flight */
 160         struct rpc_wait_queue   backlog;        /* waiting for slot */
 161         struct list_head        free;           /* free slots */
 162         struct rpc_rqst *       slot;           /* slot table storage */
 163         unsigned int            max_reqs;       /* total slots */
 164         unsigned long           state;          /* transport state */
 165         unsigned char           shutdown   : 1, /* being shut down */
 166                                 resvport   : 1; /* use a reserved port */
 167
 168         /*
 169          * XID
 170          */
 171         __u32                   xid;            /* Next XID value to use */
 172
 173         /*
 174          * State of TCP reply receive stuff
 175          */
 176         u32                     tcp_recm,       /* Fragment header */
 177                                 tcp_xid,        /* Current XID */
 178                                 tcp_reclen,     /* fragment length */
 179                                 tcp_offset;     /* fragment offset */
 180         unsigned long           tcp_copied,     /* copied to request */
 181                                 tcp_flags;
 182         /*
 183          * Connection of transports
 184          */
 185         struct work_struct      connect_worker;
 186         unsigned short          port;
 187         /*
 188          * Disconnection of idle transports
 189          */
 190         struct work_struct      task_cleanup;
 191         struct timer_list       timer;
 192         unsigned long           last_used;
 193
 194         /*
 195          * Send stuff
 196          */
 197         spinlock_t              transport_lock; /* lock transport info */
 198         spinlock_t              reserve_lock;   /* lock slot table */
 199         struct rpc_task *       snd_task;       /* Task blocked in send */
 200
 201         struct list_head        recv;
 202
 203
 204         void                    (*old_data_ready)(struct sock *, int);
 205         void                    (*old_state_change)(struct sock *);
 206         void                    (*old_write_space)(struct sock *);
 207 };
 208
 209 #define XPRT_LAST_FRAG          (1 << 0)
 210 #define XPRT_COPY_RECM          (1 << 1)
 211 #define XPRT_COPY_XID           (1 << 2)
 212 #define XPRT_COPY_DATA          (1 << 3)
 213
 214 #ifdef __KERNEL__
 215
 216 /*
 217  * Transport operations used by ULPs
 218  */
 219 struct rpc_xprt *       xprt_create_proto(int proto, struct sockaddr_in *addr, struct rpc_timeout *to);
 220 void                    xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr);
 221
 222 /*
 223  * Generic internal transport functions
 224  */
 225 void                    xprt_connect(struct rpc_task *task);
 226 void                    xprt_reserve(struct rpc_task *task);
 227 int                     xprt_reserve_xprt(struct rpc_task *task);
 228 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 229 int                     xprt_prepare_transmit(struct rpc_task *task);
 230 void                    xprt_transmit(struct rpc_task *task);
 231 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 232 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 233 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 234 void                    xprt_release(struct rpc_task *task);
 235 int                     xprt_destroy(struct rpc_xprt *xprt);
 236
 237 static inline u32 *xprt_skip_transport_header(struct rpc_xprt *xprt, u32 *p)
 238 {
 239         return p + xprt->tsh_size;
 240 }
 241
 242 /*
 243  * Transport switch helper functions
 244  */
 245 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 246 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 247 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 248 void                    xprt_wait_for_buffer_space(struct rpc_task *task);
 249 void                    xprt_write_space(struct rpc_xprt *xprt);
 250 void                    xprt_update_rtt(struct rpc_task *task);
 251 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 252 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid);
 253 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 254 void                    xprt_release_rqst_cong(struct rpc_task *task);
 255 void                    xprt_disconnect(struct rpc_xprt *xprt);
 256
 257 /*
 258  * Socket transport setup operations
 259  */
 260 int                     xs_setup_udp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 261 int                     xs_setup_tcp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 262
 263 /*
 264  * Reserved bit positions in xprt->state
 265  */
 266 #define XPRT_LOCKED             (0)
 267 #define XPRT_CONNECTED          (1)
 268 #define XPRT_CONNECTING         (2)
 269
 270 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 271 {
 272         set_bit(XPRT_CONNECTED, &xprt->state);
 273 }
 274
 275 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 276 {
 277         clear_bit(XPRT_CONNECTED, &xprt->state);
 278 }
 279
 280 static inline int xprt_connected(struct rpc_xprt *xprt)
 281 {
 282         return test_bit(XPRT_CONNECTED, &xprt->state);
 283 }
 284
 285 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 286 {
 287         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 288 }
 289
 290 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 291 {
 292         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 293 }
 294
 295 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 296 {
 297         smp_mb__before_clear_bit();
 298         clear_bit(XPRT_CONNECTING, &xprt->state);
 299         smp_mb__after_clear_bit();
 300 }
 301
 302 static inline int xprt_connecting(struct rpc_xprt *xprt)
 303 {
 304         return test_bit(XPRT_CONNECTING, &xprt->state);
 305 }
 306
 307 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 308 {
 309         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 310 }
 311
 312 #endif /* __KERNEL__*/
 313
 314 #endif /* _LINUX_SUNRPC_XPRT_H */