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
  57 /*
  58  * This describes a complete RPC request
  59  */
  60 struct rpc_rqst {
  61         /*
  62          * This is the user-visible part
  63          */
  64         struct rpc_xprt *       rq_xprt;                /* RPC client */
  65         struct xdr_buf          rq_snd_buf;             /* send buffer */
  66         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
  67
  68         /*
  69          * This is the private part
  70          */
  71         struct rpc_task *       rq_task;        /* RPC task data */
  72         __u32                   rq_xid;         /* request XID */
  73         int                     rq_cong;        /* has incremented xprt->cong */
  74         int                     rq_received;    /* receive completed */
  75         u32                     rq_seqno;       /* gss seq no. used on req. */
  76         int                     rq_enc_pages_num;
  77         struct page             **rq_enc_pages; /* scratch pages for use by
  78                                                    gss privacy code */
  79         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
  80         struct list_head        rq_list;
  81
  82         __u32 *                 rq_buffer;      /* XDR encode buffer */
  83         size_t                  rq_bufsize;
  84
  85         struct xdr_buf          rq_private_buf;         /* The receive buffer
  86                                                          * used in the softirq.
  87                                                          */
  88         unsigned long           rq_majortimeo;  /* major timeout alarm */
  89         unsigned long           rq_timeout;     /* Current timeout value */
  90         unsigned int            rq_retries;     /* # of retries */
  91
  92         /*
  93          * Partial send handling
  94          */
  95         u32                     rq_bytes_sent;  /* Bytes we have sent */
  96
  97         unsigned long           rq_xtime;       /* when transmitted */
  98         int                     rq_ntrans;
  99 };
 100 #define rq_svec                 rq_snd_buf.head
 101 #define rq_slen                 rq_snd_buf.len
 102
 103 struct rpc_xprt_ops {
 104         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
 105         int             (*reserve_xprt)(struct rpc_task *task);
 106         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 107         void            (*connect)(struct rpc_task *task);
 108         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 109         void            (*buf_free)(struct rpc_task *task);
 110         int             (*send_request)(struct rpc_task *task);
 111         void            (*set_retrans_timeout)(struct rpc_task *task);
 112         void            (*timer)(struct rpc_task *task);
 113         void            (*release_request)(struct rpc_task *task);
 114         void            (*close)(struct rpc_xprt *xprt);
 115         void            (*destroy)(struct rpc_xprt *xprt);
 116 };
 117
 118 struct rpc_xprt {
 119         struct rpc_xprt_ops *   ops;            /* transport methods */
 120         struct socket *         sock;           /* BSD socket layer */
 121         struct sock *           inet;           /* INET layer */
 122
 123         struct rpc_timeout      timeout;        /* timeout parms */
 124         struct sockaddr_in      addr;           /* server address */
 125         int                     prot;           /* IP protocol */
 126
 127         unsigned long           cong;           /* current congestion */
 128         unsigned long           cwnd;           /* congestion window */
 129
 130         size_t                  rcvsize,        /* transport rcv buffer size */
 131                                 sndsize;        /* transport send buffer size */
 132
 133         size_t                  max_payload;    /* largest RPC payload size,
 134                                                    in bytes */
 135         unsigned int            tsh_size;       /* size of transport specific
 136                                                    header */
 137
 138         struct rpc_wait_queue   sending;        /* requests waiting to send */
 139         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 140         struct rpc_wait_queue   pending;        /* requests in flight */
 141         struct rpc_wait_queue   backlog;        /* waiting for slot */
 142         struct list_head        free;           /* free slots */
 143         struct rpc_rqst *       slot;           /* slot table storage */
 144         unsigned int            max_reqs;       /* total slots */
 145         unsigned long           state;          /* transport state */
 146         unsigned char           shutdown   : 1, /* being shut down */
 147                                 resvport   : 1; /* use a reserved port */
 148
 149         /*
 150          * XID
 151          */
 152         __u32                   xid;            /* Next XID value to use */
 153
 154         /*
 155          * State of TCP reply receive stuff
 156          */
 157         u32                     tcp_recm,       /* Fragment header */
 158                                 tcp_xid,        /* Current XID */
 159                                 tcp_reclen,     /* fragment length */
 160                                 tcp_offset;     /* fragment offset */
 161         unsigned long           tcp_copied,     /* copied to request */
 162                                 tcp_flags;
 163         /*
 164          * Connection of transports
 165          */
 166         unsigned long           connect_timeout,
 167                                 bind_timeout,
 168                                 reestablish_timeout;
 169         struct work_struct      connect_worker;
 170         unsigned short          port;
 171
 172         /*
 173          * Disconnection of idle transports
 174          */
 175         struct work_struct      task_cleanup;
 176         struct timer_list       timer;
 177         unsigned long           last_used,
 178                                 idle_timeout;
 179
 180         /*
 181          * Send stuff
 182          */
 183         spinlock_t              transport_lock; /* lock transport info */
 184         spinlock_t              reserve_lock;   /* lock slot table */
 185         struct rpc_task *       snd_task;       /* Task blocked in send */
 186
 187         struct list_head        recv;
 188
 189
 190         void                    (*old_data_ready)(struct sock *, int);
 191         void                    (*old_state_change)(struct sock *);
 192         void                    (*old_write_space)(struct sock *);
 193 };
 194
 195 #define XPRT_LAST_FRAG          (1 << 0)
 196 #define XPRT_COPY_RECM          (1 << 1)
 197 #define XPRT_COPY_XID           (1 << 2)
 198 #define XPRT_COPY_DATA          (1 << 3)
 199
 200 #ifdef __KERNEL__
 201
 202 /*
 203  * Transport operations used by ULPs
 204  */
 205 struct rpc_xprt *       xprt_create_proto(int proto, struct sockaddr_in *addr, struct rpc_timeout *to);
 206 void                    xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr);
 207
 208 /*
 209  * Generic internal transport functions
 210  */
 211 void                    xprt_connect(struct rpc_task *task);
 212 void                    xprt_reserve(struct rpc_task *task);
 213 int                     xprt_reserve_xprt(struct rpc_task *task);
 214 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 215 int                     xprt_prepare_transmit(struct rpc_task *task);
 216 void                    xprt_transmit(struct rpc_task *task);
 217 void                    xprt_abort_transmit(struct rpc_task *task);
 218 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 219 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 220 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 221 void                    xprt_release(struct rpc_task *task);
 222 int                     xprt_destroy(struct rpc_xprt *xprt);
 223
 224 static inline u32 *xprt_skip_transport_header(struct rpc_xprt *xprt, u32 *p)
 225 {
 226         return p + xprt->tsh_size;
 227 }
 228
 229 /*
 230  * Transport switch helper functions
 231  */
 232 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 233 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 234 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 235 void                    xprt_wait_for_buffer_space(struct rpc_task *task);
 236 void                    xprt_write_space(struct rpc_xprt *xprt);
 237 void                    xprt_update_rtt(struct rpc_task *task);
 238 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 239 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid);
 240 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 241 void                    xprt_release_rqst_cong(struct rpc_task *task);
 242 void                    xprt_disconnect(struct rpc_xprt *xprt);
 243
 244 /*
 245  * Socket transport setup operations
 246  */
 247 int                     xs_setup_udp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 248 int                     xs_setup_tcp(struct rpc_xprt *xprt, struct rpc_timeout *to);
 249
 250 /*
 251  * Reserved bit positions in xprt->state
 252  */
 253 #define XPRT_LOCKED             (0)
 254 #define XPRT_CONNECTED          (1)
 255 #define XPRT_CONNECTING         (2)
 256
 257 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 258 {
 259         set_bit(XPRT_CONNECTED, &xprt->state);
 260 }
 261
 262 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 263 {
 264         clear_bit(XPRT_CONNECTED, &xprt->state);
 265 }
 266
 267 static inline int xprt_connected(struct rpc_xprt *xprt)
 268 {
 269         return test_bit(XPRT_CONNECTED, &xprt->state);
 270 }
 271
 272 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 273 {
 274         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 275 }
 276
 277 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 278 {
 279         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 280 }
 281
 282 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 283 {
 284         smp_mb__before_clear_bit();
 285         clear_bit(XPRT_CONNECTING, &xprt->state);
 286         smp_mb__after_clear_bit();
 287 }
 288
 289 static inline int xprt_connecting(struct rpc_xprt *xprt)
 290 {
 291         return test_bit(XPRT_CONNECTING, &xprt->state);
 292 }
 293
 294 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 295 {
 296         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 297 }
 298
 299 #endif /* __KERNEL__*/
 300
 301 #endif /* _LINUX_SUNRPC_XPRT_H */