LXR linux/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 */
  29struct 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
  37enum 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
  49struct rpc_task;
  50struct rpc_xprt;
  51struct seq_file;
  52
  53/*
  54 * This describes a complete RPC request
  55 */
  56struct 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
 104struct 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
 122struct 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
 195struct 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
 202struct 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 */
 213struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
 214void                    xprt_connect(struct rpc_task *task);
 215void                    xprt_reserve(struct rpc_task *task);
 216int                     xprt_reserve_xprt(struct rpc_task *task);
 217int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 218int                     xprt_prepare_transmit(struct rpc_task *task);
 219void                    xprt_transmit(struct rpc_task *task);
 220void                    xprt_end_transmit(struct rpc_task *task);
 221int                     xprt_adjust_timeout(struct rpc_rqst *req);
 222void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 223void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 224void                    xprt_release(struct rpc_task *task);
 225struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
 226void                    xprt_put(struct rpc_xprt *xprt);
 227
 228static 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 */
 236int                     xprt_register_transport(struct xprt_class *type);
 237int                     xprt_unregister_transport(struct xprt_class *type);
 238void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 239void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 240void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 241void                    xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
 242void                    xprt_write_space(struct rpc_xprt *xprt);
 243void                    xprt_update_rtt(struct rpc_task *task);
 244void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 245struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
 246void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 247void                    xprt_release_rqst_cong(struct rpc_task *task);
 248void                    xprt_disconnect_done(struct rpc_xprt *xprt);
 249void                    xprt_force_disconnect(struct rpc_xprt *xprt);
 250void                    xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
 251
 252/*
 253 * Reserved bit positions in xprt->state
 254 */
 255#define XPRT_LOCKED             (0)
 256#define XPRT_CONNECTED          (1)
 257#define XPRT_CONNECTING         (2)
 258#define XPRT_CLOSE_WAIT         (3)
 259#define XPRT_BOUND              (4)
 260#define XPRT_BINDING            (5)
 261#define XPRT_CLOSING            (6)
 262
 263static inline void xprt_set_connected(struct rpc_xprt *xprt)
 264{
 265        set_bit(XPRT_CONNECTED, &xprt->state);
 266}
 267
 268static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 269{
 270        clear_bit(XPRT_CONNECTED, &xprt->state);
 271}
 272
 273static inline int xprt_connected(struct rpc_xprt *xprt)
 274{
 275        return test_bit(XPRT_CONNECTED, &xprt->state);
 276}
 277
 278static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 279{
 280        return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 281}
 282
 283static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 284{
 285        return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 286}
 287
 288static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 289{
 290        smp_mb__before_clear_bit();
 291        clear_bit(XPRT_CONNECTING, &xprt->state);
 292        smp_mb__after_clear_bit();
 293}
 294
 295static inline int xprt_connecting(struct rpc_xprt *xprt)
 296{
 297        return test_bit(XPRT_CONNECTING, &xprt->state);
 298}
 299
 300static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 301{
 302        return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 303}
 304
 305static inline void xprt_set_bound(struct rpc_xprt *xprt)
 306{
 307        test_and_set_bit(XPRT_BOUND, &xprt->state);
 308}
 309
 310static inline int xprt_bound(struct rpc_xprt *xprt)
 311{
 312        return test_bit(XPRT_BOUND, &xprt->state);
 313}
 314
 315static inline void xprt_clear_bound(struct rpc_xprt *xprt)
 316{
 317        clear_bit(XPRT_BOUND, &xprt->state);
 318}
 319
 320static inline void xprt_clear_binding(struct rpc_xprt *xprt)
 321{
 322        smp_mb__before_clear_bit();
 323        clear_bit(XPRT_BINDING, &xprt->state);
 324        smp_mb__after_clear_bit();
 325}
 326
 327static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 328{
 329        return test_and_set_bit(XPRT_BINDING, &xprt->state);
 330}
 331
 332#endif /* __KERNEL__*/
 333
 334#endif /* _LINUX_SUNRPC_XPRT_H */
 335