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_NETID,
  45         RPC_DISPLAY_MAX,
  46 };
  47
  48 struct rpc_task;
  49 struct rpc_xprt;
  50 struct seq_file;
  51
  52 /*
  53  * This describes a complete RPC request
  54  */
  55 struct rpc_rqst {
  56         /*
  57          * This is the user-visible part
  58          */
  59         struct rpc_xprt *       rq_xprt;                /* RPC client */
  60         struct xdr_buf          rq_snd_buf;             /* send buffer */
  61         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
  62
  63         /*
  64          * This is the private part
  65          */
  66         struct rpc_task *       rq_task;        /* RPC task data */
  67         __be32                  rq_xid;         /* request XID */
  68         int                     rq_cong;        /* has incremented xprt->cong */
  69         int                     rq_reply_bytes_recvd;   /* number of reply */
  70                                                         /* bytes received */
  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 #if defined(CONFIG_NFS_V4_1)
 102         struct list_head        rq_bc_list;     /* Callback service list */
 103         unsigned long           rq_bc_pa_state; /* Backchannel prealloc state */
 104         struct list_head        rq_bc_pa_list;  /* Backchannel prealloc list */
 105 #endif /* CONFIG_NFS_V4_1 */
 106 };
 107 #define rq_svec                 rq_snd_buf.head
 108 #define rq_slen                 rq_snd_buf.len
 109
 110 struct rpc_xprt_ops {
 111         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
 112         int             (*reserve_xprt)(struct rpc_task *task);
 113         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 114         void            (*rpcbind)(struct rpc_task *task);
 115         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
 116         void            (*connect)(struct rpc_task *task);
 117         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 118         void            (*buf_free)(void *buffer);
 119         int             (*send_request)(struct rpc_task *task);
 120         void            (*set_retrans_timeout)(struct rpc_task *task);
 121         void            (*timer)(struct rpc_task *task);
 122         void            (*release_request)(struct rpc_task *task);
 123         void            (*close)(struct rpc_xprt *xprt);
 124         void            (*destroy)(struct rpc_xprt *xprt);
 125         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 126 };
 127
 128 struct rpc_xprt {
 129         struct kref             kref;           /* Reference count */
 130         struct rpc_xprt_ops *   ops;            /* transport methods */
 131
 132         const struct rpc_timeout *timeout;      /* timeout parms */
 133         struct sockaddr_storage addr;           /* server address */
 134         size_t                  addrlen;        /* size of server address */
 135         int                     prot;           /* IP protocol */
 136
 137         unsigned long           cong;           /* current congestion */
 138         unsigned long           cwnd;           /* congestion window */
 139
 140         size_t                  max_payload;    /* largest RPC payload size,
 141                                                    in bytes */
 142         unsigned int            tsh_size;       /* size of transport specific
 143                                                    header */
 144
 145         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
 146         struct rpc_wait_queue   sending;        /* requests waiting to send */
 147         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 148         struct rpc_wait_queue   pending;        /* requests in flight */
 149         struct rpc_wait_queue   backlog;        /* waiting for slot */
 150         struct list_head        free;           /* free slots */
 151         struct rpc_rqst *       slot;           /* slot table storage */
 152         unsigned int            max_reqs;       /* total slots */
 153         unsigned long           state;          /* transport state */
 154         unsigned char           shutdown   : 1, /* being shut down */
 155                                 resvport   : 1; /* use a reserved port */
 156         unsigned int            bind_index;     /* bind function index */
 157
 158         /*
 159          * Connection of transports
 160          */
 161         unsigned long           connect_timeout,
 162                                 bind_timeout,
 163                                 reestablish_timeout;
 164         unsigned int            connect_cookie; /* A cookie that gets bumped
 165                                                    every time the transport
 166                                                    is reconnected */
 167
 168         /*
 169          * Disconnection of idle transports
 170          */
 171         struct work_struct      task_cleanup;
 172         struct timer_list       timer;
 173         unsigned long           last_used,
 174                                 idle_timeout;
 175
 176         /*
 177          * Send stuff
 178          */
 179         spinlock_t              transport_lock; /* lock transport info */
 180         spinlock_t              reserve_lock;   /* lock slot table */
 181         u32                     xid;            /* Next XID value to use */
 182         struct rpc_task *       snd_task;       /* Task blocked in send */
 183 #if defined(CONFIG_NFS_V4_1)
 184         struct svc_serv         *bc_serv;       /* The RPC service which will */
 185                                                 /* process the callback */
 186         unsigned int            bc_alloc_count; /* Total number of preallocs */
 187         spinlock_t              bc_pa_lock;     /* Protects the preallocated
 188                                                  * items */
 189         struct list_head        bc_pa_list;     /* List of preallocated
 190                                                  * backchannel rpc_rqst's */
 191 #endif /* CONFIG_NFS_V4_1 */
 192         struct list_head        recv;
 193
 194         struct {
 195                 unsigned long           bind_count,     /* total number of binds */
 196                                         connect_count,  /* total number of connects */
 197                                         connect_start,  /* connect start timestamp */
 198                                         connect_time,   /* jiffies waiting for connect */
 199                                         sends,          /* how many complete requests */
 200                                         recvs,          /* how many complete requests */
 201                                         bad_xids;       /* lookup_rqst didn't find XID */
 202
 203                 unsigned long long      req_u,          /* average requests on the wire */
 204                                         bklog_u;        /* backlog queue utilization */
 205         } stat;
 206
 207         const char              *address_strings[RPC_DISPLAY_MAX];
 208 };
 209
 210 #if defined(CONFIG_NFS_V4_1)
 211 /*
 212  * Backchannel flags
 213  */
 214 #define RPC_BC_PA_IN_USE        0x0001          /* Preallocated backchannel */
 215                                                 /* buffer in use */
 216 #endif /* CONFIG_NFS_V4_1 */
 217
 218 #if defined(CONFIG_NFS_V4_1)
 219 static inline int bc_prealloc(struct rpc_rqst *req)
 220 {
 221         return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
 222 }
 223 #else
 224 static inline int bc_prealloc(struct rpc_rqst *req)
 225 {
 226         return 0;
 227 }
 228 #endif /* CONFIG_NFS_V4_1 */
 229
 230 struct xprt_create {
 231         int                     ident;          /* XPRT_TRANSPORT identifier */
 232         struct sockaddr *       srcaddr;        /* optional local address */
 233         struct sockaddr *       dstaddr;        /* remote peer address */
 234         size_t                  addrlen;
 235 };
 236
 237 struct xprt_class {
 238         struct list_head        list;
 239         int                     ident;          /* XPRT_TRANSPORT identifier */
 240         struct rpc_xprt *       (*setup)(struct xprt_create *);
 241         struct module           *owner;
 242         char                    name[32];
 243 };
 244
 245 /*
 246  * Generic internal transport functions
 247  */
 248 struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
 249 void                    xprt_connect(struct rpc_task *task);
 250 void                    xprt_reserve(struct rpc_task *task);
 251 int                     xprt_reserve_xprt(struct rpc_task *task);
 252 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 253 int                     xprt_prepare_transmit(struct rpc_task *task);
 254 void                    xprt_transmit(struct rpc_task *task);
 255 void                    xprt_end_transmit(struct rpc_task *task);
 256 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 257 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 258 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 259 void                    xprt_release(struct rpc_task *task);
 260 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
 261 void                    xprt_put(struct rpc_xprt *xprt);
 262
 263 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
 264 {
 265         return p + xprt->tsh_size;
 266 }
 267
 268 /*
 269  * Transport switch helper functions
 270  */
 271 int                     xprt_register_transport(struct xprt_class *type);
 272 int                     xprt_unregister_transport(struct xprt_class *type);
 273 int                     xprt_load_transport(const char *);
 274 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 275 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 276 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 277 void                    xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
 278 void                    xprt_write_space(struct rpc_xprt *xprt);
 279 void                    xprt_update_rtt(struct rpc_task *task);
 280 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 281 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
 282 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 283 void                    xprt_release_rqst_cong(struct rpc_task *task);
 284 void                    xprt_disconnect_done(struct rpc_xprt *xprt);
 285 void                    xprt_force_disconnect(struct rpc_xprt *xprt);
 286 void                    xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
 287
 288 /*
 289  * Reserved bit positions in xprt->state
 290  */
 291 #define XPRT_LOCKED             (0)
 292 #define XPRT_CONNECTED          (1)
 293 #define XPRT_CONNECTING         (2)
 294 #define XPRT_CLOSE_WAIT         (3)
 295 #define XPRT_BOUND              (4)
 296 #define XPRT_BINDING            (5)
 297 #define XPRT_CLOSING            (6)
 298 #define XPRT_CONNECTION_ABORT   (7)
 299 #define XPRT_CONNECTION_CLOSE   (8)
 300
 301 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 302 {
 303         set_bit(XPRT_CONNECTED, &xprt->state);
 304 }
 305
 306 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 307 {
 308         clear_bit(XPRT_CONNECTED, &xprt->state);
 309 }
 310
 311 static inline int xprt_connected(struct rpc_xprt *xprt)
 312 {
 313         return test_bit(XPRT_CONNECTED, &xprt->state);
 314 }
 315
 316 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 317 {
 318         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 319 }
 320
 321 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 322 {
 323         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 324 }
 325
 326 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 327 {
 328         smp_mb__before_clear_bit();
 329         clear_bit(XPRT_CONNECTING, &xprt->state);
 330         smp_mb__after_clear_bit();
 331 }
 332
 333 static inline int xprt_connecting(struct rpc_xprt *xprt)
 334 {
 335         return test_bit(XPRT_CONNECTING, &xprt->state);
 336 }
 337
 338 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 339 {
 340         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 341 }
 342
 343 static inline void xprt_set_bound(struct rpc_xprt *xprt)
 344 {
 345         test_and_set_bit(XPRT_BOUND, &xprt->state);
 346 }
 347
 348 static inline int xprt_bound(struct rpc_xprt *xprt)
 349 {
 350         return test_bit(XPRT_BOUND, &xprt->state);
 351 }
 352
 353 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
 354 {
 355         clear_bit(XPRT_BOUND, &xprt->state);
 356 }
 357
 358 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
 359 {
 360         smp_mb__before_clear_bit();
 361         clear_bit(XPRT_BINDING, &xprt->state);
 362         smp_mb__after_clear_bit();
 363 }
 364
 365 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 366 {
 367         return test_and_set_bit(XPRT_BINDING, &xprt->state);
 368 }
 369
 370 #endif /* __KERNEL__*/
 371
 372 #endif /* _LINUX_SUNRPC_XPRT_H */