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_bufsize,
  80                                 rq_callsize,
  81                                 rq_rcvsize;
  82
  83         struct xdr_buf          rq_private_buf;         /* The receive buffer
  84                                                          * used in the softirq.
  85                                                          */
  86         unsigned long           rq_majortimeo;  /* major timeout alarm */
  87         unsigned long           rq_timeout;     /* Current timeout value */
  88         unsigned int            rq_retries;     /* # of retries */
  89
  90         /*
  91          * Partial send handling
  92          */
  93         u32                     rq_bytes_sent;  /* Bytes we have sent */
  94
  95         unsigned long           rq_xtime;       /* when transmitted */
  96         int                     rq_ntrans;
  97 };
  98 #define rq_svec                 rq_snd_buf.head
  99 #define rq_slen                 rq_snd_buf.len
 100
 101 struct rpc_xprt_ops {
 102         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
 103         int             (*reserve_xprt)(struct rpc_task *task);
 104         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 105         void            (*rpcbind)(struct rpc_task *task);
 106         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
 107         void            (*connect)(struct rpc_task *task);
 108         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 109         void            (*buf_free)(void *buffer);
 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         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 117 };
 118
 119 struct rpc_xprt {
 120         struct kref             kref;           /* Reference count */
 121         struct rpc_xprt_ops *   ops;            /* transport methods */
 122
 123         const struct rpc_timeout *timeout;      /* timeout parms */
 124         struct sockaddr_storage addr;           /* server address */
 125         size_t                  addrlen;        /* size of server address */
 126         int                     prot;           /* IP protocol */
 127
 128         unsigned long           cong;           /* current congestion */
 129         unsigned long           cwnd;           /* congestion window */
 130
 131         size_t                  max_payload;    /* largest RPC payload size,
 132                                                    in bytes */
 133         unsigned int            tsh_size;       /* size of transport specific
 134                                                    header */
 135
 136         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
 137         struct rpc_wait_queue   sending;        /* requests waiting to send */
 138         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 139         struct rpc_wait_queue   pending;        /* requests in flight */
 140         struct rpc_wait_queue   backlog;        /* waiting for slot */
 141         struct list_head        free;           /* free slots */
 142         struct rpc_rqst *       slot;           /* slot table storage */
 143         unsigned int            max_reqs;       /* total slots */
 144         unsigned long           state;          /* transport state */
 145         unsigned char           shutdown   : 1, /* being shut down */
 146                                 resvport   : 1; /* use a reserved port */
 147         unsigned int            bind_index;     /* bind function index */
 148
 149         /*
 150          * Connection of transports
 151          */
 152         unsigned long           connect_timeout,
 153                                 bind_timeout,
 154                                 reestablish_timeout;
 155
 156         /*
 157          * Disconnection of idle transports
 158          */
 159         struct work_struct      task_cleanup;
 160         struct timer_list       timer;
 161         unsigned long           last_used,
 162                                 idle_timeout;
 163
 164         /*
 165          * Send stuff
 166          */
 167         spinlock_t              transport_lock; /* lock transport info */
 168         spinlock_t              reserve_lock;   /* lock slot table */
 169         u32                     xid;            /* Next XID value to use */
 170         struct rpc_task *       snd_task;       /* Task blocked in send */
 171         struct list_head        recv;
 172
 173         struct {
 174                 unsigned long           bind_count,     /* total number of binds */
 175                                         connect_count,  /* total number of connects */
 176                                         connect_start,  /* connect start timestamp */
 177                                         connect_time,   /* jiffies waiting for connect */
 178                                         sends,          /* how many complete requests */
 179                                         recvs,          /* how many complete requests */
 180                                         bad_xids;       /* lookup_rqst didn't find XID */
 181
 182                 unsigned long long      req_u,          /* average requests on the wire */
 183                                         bklog_u;        /* backlog queue utilization */
 184         } stat;
 185
 186         const char              *address_strings[RPC_DISPLAY_MAX];
 187 };
 188
 189 struct xprt_create {
 190         int                     ident;          /* XPRT_TRANSPORT identifier */
 191         struct sockaddr *       srcaddr;        /* optional local address */
 192         struct sockaddr *       dstaddr;        /* remote peer address */
 193         size_t                  addrlen;
 194 };
 195
 196 struct xprt_class {
 197         struct list_head        list;
 198         int                     ident;          /* XPRT_TRANSPORT identifier */
 199         struct rpc_xprt *       (*setup)(struct xprt_create *);
 200         struct module           *owner;
 201         char                    name[32];
 202 };
 203
 204 /*
 205  * Generic internal transport functions
 206  */
 207 struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
 208 void                    xprt_connect(struct rpc_task *task);
 209 void                    xprt_reserve(struct rpc_task *task);
 210 int                     xprt_reserve_xprt(struct rpc_task *task);
 211 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 212 int                     xprt_prepare_transmit(struct rpc_task *task);
 213 void                    xprt_transmit(struct rpc_task *task);
 214 void                    xprt_end_transmit(struct rpc_task *task);
 215 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 216 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 217 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 218 void                    xprt_release(struct rpc_task *task);
 219 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
 220 void                    xprt_put(struct rpc_xprt *xprt);
 221
 222 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
 223 {
 224         return p + xprt->tsh_size;
 225 }
 226
 227 /*
 228  * Transport switch helper functions
 229  */
 230 int                     xprt_register_transport(struct xprt_class *type);
 231 int                     xprt_unregister_transport(struct xprt_class *type);
 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, __be32 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_done(struct rpc_xprt *xprt);
 243 void                    xprt_force_disconnect(struct rpc_xprt *xprt);
 244
 245 /*
 246  * Reserved bit positions in xprt->state
 247  */
 248 #define XPRT_LOCKED             (0)
 249 #define XPRT_CONNECTED          (1)
 250 #define XPRT_CONNECTING         (2)
 251 #define XPRT_CLOSE_WAIT         (3)
 252 #define XPRT_BOUND              (4)
 253 #define XPRT_BINDING            (5)
 254 #define XPRT_CLOSING            (6)
 255
 256 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 257 {
 258         set_bit(XPRT_CONNECTED, &xprt->state);
 259 }
 260
 261 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 262 {
 263         clear_bit(XPRT_CONNECTED, &xprt->state);
 264 }
 265
 266 static inline int xprt_connected(struct rpc_xprt *xprt)
 267 {
 268         return test_bit(XPRT_CONNECTED, &xprt->state);
 269 }
 270
 271 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 272 {
 273         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 274 }
 275
 276 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 277 {
 278         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 279 }
 280
 281 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 282 {
 283         smp_mb__before_clear_bit();
 284         clear_bit(XPRT_CONNECTING, &xprt->state);
 285         smp_mb__after_clear_bit();
 286 }
 287
 288 static inline int xprt_connecting(struct rpc_xprt *xprt)
 289 {
 290         return test_bit(XPRT_CONNECTING, &xprt->state);
 291 }
 292
 293 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 294 {
 295         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 296 }
 297
 298 static inline void xprt_set_bound(struct rpc_xprt *xprt)
 299 {
 300         test_and_set_bit(XPRT_BOUND, &xprt->state);
 301 }
 302
 303 static inline int xprt_bound(struct rpc_xprt *xprt)
 304 {
 305         return test_bit(XPRT_BOUND, &xprt->state);
 306 }
 307
 308 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
 309 {
 310         clear_bit(XPRT_BOUND, &xprt->state);
 311 }
 312
 313 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
 314 {
 315         smp_mb__before_clear_bit();
 316         clear_bit(XPRT_BINDING, &xprt->state);
 317         smp_mb__after_clear_bit();
 318 }
 319
 320 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 321 {
 322         return test_and_set_bit(XPRT_BINDING, &xprt->state);
 323 }
 324
 325 #endif /* __KERNEL__*/
 326
 327 #endif /* _LINUX_SUNRPC_XPRT_H */