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_reply_bytes_recvd;   /* number of reply */
  71                                                         /* bytes received */
  72         u32                     rq_seqno;       /* gss seq no. used on req. */
  73         int                     rq_enc_pages_num;
  74         struct page             **rq_enc_pages; /* scratch pages for use by
  75                                                    gss privacy code */
  76         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
  77         struct list_head        rq_list;
  78
  79         __u32 *                 rq_buffer;      /* XDR encode buffer */
  80         size_t                  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         unsigned int            rq_connect_cookie;
  90                                                 /* A cookie used to track the
  91                                                    state of the transport
  92                                                    connection */
  93
  94         /*
  95          * Partial send handling
  96          */
  97         u32                     rq_bytes_sent;  /* Bytes we have sent */
  98
  99         unsigned long           rq_xtime;       /* when transmitted */
 100         int                     rq_ntrans;
 101
 102 #if defined(CONFIG_NFS_V4_1)
 103         struct list_head        rq_bc_list;     /* Callback service list */
 104         unsigned long           rq_bc_pa_state; /* Backchannel prealloc state */
 105         struct list_head        rq_bc_pa_list;  /* Backchannel prealloc list */
 106 #endif /* CONFIG_NFS_V4_1 */
 107 };
 108 #define rq_svec                 rq_snd_buf.head
 109 #define rq_slen                 rq_snd_buf.len
 110
 111 struct rpc_xprt_ops {
 112         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
 113         int             (*reserve_xprt)(struct rpc_task *task);
 114         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
 115         void            (*rpcbind)(struct rpc_task *task);
 116         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
 117         void            (*connect)(struct rpc_task *task);
 118         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
 119         void            (*buf_free)(void *buffer);
 120         int             (*send_request)(struct rpc_task *task);
 121         void            (*set_retrans_timeout)(struct rpc_task *task);
 122         void            (*timer)(struct rpc_task *task);
 123         void            (*release_request)(struct rpc_task *task);
 124         void            (*close)(struct rpc_xprt *xprt);
 125         void            (*destroy)(struct rpc_xprt *xprt);
 126         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 127 };
 128
 129 struct rpc_xprt {
 130         struct kref             kref;           /* Reference count */
 131         struct rpc_xprt_ops *   ops;            /* transport methods */
 132
 133         const struct rpc_timeout *timeout;      /* timeout parms */
 134         struct sockaddr_storage addr;           /* server address */
 135         size_t                  addrlen;        /* size of server address */
 136         int                     prot;           /* IP protocol */
 137
 138         unsigned long           cong;           /* current congestion */
 139         unsigned long           cwnd;           /* congestion window */
 140
 141         size_t                  max_payload;    /* largest RPC payload size,
 142                                                    in bytes */
 143         unsigned int            tsh_size;       /* size of transport specific
 144                                                    header */
 145
 146         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
 147         struct rpc_wait_queue   sending;        /* requests waiting to send */
 148         struct rpc_wait_queue   resend;         /* requests waiting to resend */
 149         struct rpc_wait_queue   pending;        /* requests in flight */
 150         struct rpc_wait_queue   backlog;        /* waiting for slot */
 151         struct list_head        free;           /* free slots */
 152         struct rpc_rqst *       slot;           /* slot table storage */
 153         unsigned int            max_reqs;       /* total slots */
 154         unsigned long           state;          /* transport state */
 155         unsigned char           shutdown   : 1, /* being shut down */
 156                                 resvport   : 1; /* use a reserved port */
 157         unsigned int            bind_index;     /* bind function index */
 158
 159         /*
 160          * Connection of transports
 161          */
 162         unsigned long           connect_timeout,
 163                                 bind_timeout,
 164                                 reestablish_timeout;
 165         unsigned int            connect_cookie; /* A cookie that gets bumped
 166                                                    every time the transport
 167                                                    is reconnected */
 168
 169         /*
 170          * Disconnection of idle transports
 171          */
 172         struct work_struct      task_cleanup;
 173         struct timer_list       timer;
 174         unsigned long           last_used,
 175                                 idle_timeout;
 176
 177         /*
 178          * Send stuff
 179          */
 180         spinlock_t              transport_lock; /* lock transport info */
 181         spinlock_t              reserve_lock;   /* lock slot table */
 182         u32                     xid;            /* Next XID value to use */
 183         struct rpc_task *       snd_task;       /* Task blocked in send */
 184 #if defined(CONFIG_NFS_V4_1)
 185         struct svc_serv         *bc_serv;       /* The RPC service which will */
 186                                                 /* process the callback */
 187         unsigned int            bc_alloc_count; /* Total number of preallocs */
 188         spinlock_t              bc_pa_lock;     /* Protects the preallocated
 189                                                  * items */
 190         struct list_head        bc_pa_list;     /* List of preallocated
 191                                                  * backchannel rpc_rqst's */
 192 #endif /* CONFIG_NFS_V4_1 */
 193         struct list_head        recv;
 194
 195         struct {
 196                 unsigned long           bind_count,     /* total number of binds */
 197                                         connect_count,  /* total number of connects */
 198                                         connect_start,  /* connect start timestamp */
 199                                         connect_time,   /* jiffies waiting for connect */
 200                                         sends,          /* how many complete requests */
 201                                         recvs,          /* how many complete requests */
 202                                         bad_xids;       /* lookup_rqst didn't find XID */
 203
 204                 unsigned long long      req_u,          /* average requests on the wire */
 205                                         bklog_u;        /* backlog queue utilization */
 206         } stat;
 207
 208         const char              *address_strings[RPC_DISPLAY_MAX];
 209 };
 210
 211 #if defined(CONFIG_NFS_V4_1)
 212 /*
 213  * Backchannel flags
 214  */
 215 #define RPC_BC_PA_IN_USE        0x0001          /* Preallocated backchannel */
 216                                                 /* buffer in use */
 217 #endif /* CONFIG_NFS_V4_1 */
 218
 219 #if defined(CONFIG_NFS_V4_1)
 220 static inline int bc_prealloc(struct rpc_rqst *req)
 221 {
 222         return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
 223 }
 224 #else
 225 static inline int bc_prealloc(struct rpc_rqst *req)
 226 {
 227         return 0;
 228 }
 229 #endif /* CONFIG_NFS_V4_1 */
 230
 231 struct xprt_create {
 232         int                     ident;          /* XPRT_TRANSPORT identifier */
 233         struct sockaddr *       srcaddr;        /* optional local address */
 234         struct sockaddr *       dstaddr;        /* remote peer address */
 235         size_t                  addrlen;
 236 };
 237
 238 struct xprt_class {
 239         struct list_head        list;
 240         int                     ident;          /* XPRT_TRANSPORT identifier */
 241         struct rpc_xprt *       (*setup)(struct xprt_create *);
 242         struct module           *owner;
 243         char                    name[32];
 244 };
 245
 246 /*
 247  * Generic internal transport functions
 248  */
 249 struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
 250 void                    xprt_connect(struct rpc_task *task);
 251 void                    xprt_reserve(struct rpc_task *task);
 252 int                     xprt_reserve_xprt(struct rpc_task *task);
 253 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
 254 int                     xprt_prepare_transmit(struct rpc_task *task);
 255 void                    xprt_transmit(struct rpc_task *task);
 256 void                    xprt_end_transmit(struct rpc_task *task);
 257 int                     xprt_adjust_timeout(struct rpc_rqst *req);
 258 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
 259 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 260 void                    xprt_release(struct rpc_task *task);
 261 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
 262 void                    xprt_put(struct rpc_xprt *xprt);
 263
 264 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
 265 {
 266         return p + xprt->tsh_size;
 267 }
 268
 269 /*
 270  * Transport switch helper functions
 271  */
 272 int                     xprt_register_transport(struct xprt_class *type);
 273 int                     xprt_unregister_transport(struct xprt_class *type);
 274 int                     xprt_load_transport(const char *);
 275 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
 276 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
 277 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
 278 void                    xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
 279 void                    xprt_write_space(struct rpc_xprt *xprt);
 280 void                    xprt_update_rtt(struct rpc_task *task);
 281 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
 282 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
 283 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
 284 void                    xprt_release_rqst_cong(struct rpc_task *task);
 285 void                    xprt_disconnect_done(struct rpc_xprt *xprt);
 286 void                    xprt_force_disconnect(struct rpc_xprt *xprt);
 287 void                    xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
 288
 289 /*
 290  * Reserved bit positions in xprt->state
 291  */
 292 #define XPRT_LOCKED             (0)
 293 #define XPRT_CONNECTED          (1)
 294 #define XPRT_CONNECTING         (2)
 295 #define XPRT_CLOSE_WAIT         (3)
 296 #define XPRT_BOUND              (4)
 297 #define XPRT_BINDING            (5)
 298 #define XPRT_CLOSING            (6)
 299 #define XPRT_CONNECTION_ABORT   (7)
 300 #define XPRT_CONNECTION_CLOSE   (8)
 301
 302 static inline void xprt_set_connected(struct rpc_xprt *xprt)
 303 {
 304         set_bit(XPRT_CONNECTED, &xprt->state);
 305 }
 306
 307 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
 308 {
 309         clear_bit(XPRT_CONNECTED, &xprt->state);
 310 }
 311
 312 static inline int xprt_connected(struct rpc_xprt *xprt)
 313 {
 314         return test_bit(XPRT_CONNECTED, &xprt->state);
 315 }
 316
 317 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
 318 {
 319         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
 320 }
 321
 322 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
 323 {
 324         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
 325 }
 326
 327 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
 328 {
 329         smp_mb__before_clear_bit();
 330         clear_bit(XPRT_CONNECTING, &xprt->state);
 331         smp_mb__after_clear_bit();
 332 }
 333
 334 static inline int xprt_connecting(struct rpc_xprt *xprt)
 335 {
 336         return test_bit(XPRT_CONNECTING, &xprt->state);
 337 }
 338
 339 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
 340 {
 341         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
 342 }
 343
 344 static inline void xprt_set_bound(struct rpc_xprt *xprt)
 345 {
 346         test_and_set_bit(XPRT_BOUND, &xprt->state);
 347 }
 348
 349 static inline int xprt_bound(struct rpc_xprt *xprt)
 350 {
 351         return test_bit(XPRT_BOUND, &xprt->state);
 352 }
 353
 354 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
 355 {
 356         clear_bit(XPRT_BOUND, &xprt->state);
 357 }
 358
 359 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
 360 {
 361         smp_mb__before_clear_bit();
 362         clear_bit(XPRT_BINDING, &xprt->state);
 363         smp_mb__after_clear_bit();
 364 }
 365
 366 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 367 {
 368         return test_and_set_bit(XPRT_BINDING, &xprt->state);
 369 }
 370
 371 #endif /* __KERNEL__*/
 372
 373 #endif /* _LINUX_SUNRPC_XPRT_H */