2 * linux/include/linux/sunrpc/clnt_xprt.h
4 * Declarations for the RPC transport interface.
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
9 #ifndef _LINUX_SUNRPC_XPRT_H
10 #define _LINUX_SUNRPC_XPRT_H
12 #include <linux/uio.h>
13 #include <linux/socket.h>
15 #include <linux/sunrpc/sched.h>
16 #include <linux/sunrpc/xdr.h>
19 * The transport code maintains an estimate on the maximum number of out-
20 * standing RPC requests, using a smoothed version of the congestion
21 * avoidance implemented in 44BSD. This is basically the Van Jacobson
22 * congestion algorithm: If a retransmit occurs, the congestion window is
23 * halved; otherwise, it is incremented by 1/cwnd when
25 * - a reply is received and
26 * - a full number of requests are outstanding and
27 * - the congestion window hasn't been updated recently.
29 * Upper procedures may check whether a request would block waiting for
30 * a free RPC slot by using the RPC_CONGESTED() macro.
32 extern unsigned int xprt_udp_slot_table_entries;
33 extern unsigned int xprt_tcp_slot_table_entries;
35 #define RPC_MIN_SLOT_TABLE (2U)
36 #define RPC_DEF_SLOT_TABLE (16U)
37 #define RPC_MAX_SLOT_TABLE (128U)
39 #define RPC_CWNDSHIFT (8U)
40 #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT)
41 #define RPC_INITCWND RPC_CWNDSCALE
42 #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT)
43 #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
45 /* Default timeout values */
46 #define RPC_MAX_UDP_TIMEOUT (60*HZ)
47 #define RPC_MAX_TCP_TIMEOUT (600*HZ)
50 * Wait duration for an RPC TCP connection to be established. Solaris
51 * NFS over TCP uses 60 seconds, for example, which is in line with how
52 * long a server takes to reboot.
54 #define RPC_CONNECT_TIMEOUT (60*HZ)
57 * Delay an arbitrary number of seconds before attempting to reconnect
60 #define RPC_REESTABLISH_TIMEOUT (15*HZ)
63 * RPC transport idle timeout.
65 #define RPC_IDLE_DISCONNECT_TIMEOUT (5*60*HZ)
68 * RPC call and reply header size as number of 32bit words (verifier
69 * size computed separately)
71 #define RPC_CALLHDRSIZE 6
72 #define RPC_REPHDRSIZE 4
75 * This describes a timeout strategy
78 unsigned long to_initval, /* initial timeout */
79 to_maxval, /* max timeout */
80 to_increment; /* if !exponential */
81 unsigned int to_retries; /* max # of retries */
82 unsigned char to_exponential;
86 * This describes a complete RPC request
90 * This is the user-visible part
92 struct rpc_xprt * rq_xprt; /* RPC client */
93 struct xdr_buf rq_snd_buf; /* send buffer */
94 struct xdr_buf rq_rcv_buf; /* recv buffer */
97 * This is the private part
99 struct rpc_task * rq_task; /* RPC task data */
100 __u32 rq_xid; /* request XID */
101 int rq_cong; /* has incremented xprt->cong */
102 int rq_received; /* receive completed */
103 u32 rq_seqno; /* gss seq no. used on req. */
105 struct list_head rq_list;
107 struct xdr_buf rq_private_buf; /* The receive buffer
108 * used in the softirq.
110 unsigned long rq_majortimeo; /* major timeout alarm */
111 unsigned long rq_timeout; /* Current timeout value */
112 unsigned int rq_retries; /* # of retries */
114 * For authentication (e.g. auth_des)
119 * Partial send handling
122 u32 rq_bytes_sent; /* Bytes we have sent */
124 unsigned long rq_xtime; /* when transmitted */
127 #define rq_svec rq_snd_buf.head
128 #define rq_slen rq_snd_buf.len
133 struct rpc_xprt_ops {
134 void (*set_buffer_size)(struct rpc_xprt *xprt);
135 void (*connect)(struct rpc_task *task);
136 int (*send_request)(struct rpc_task *task);
137 void (*close)(struct rpc_xprt *xprt);
138 void (*destroy)(struct rpc_xprt *xprt);
142 struct rpc_xprt_ops * ops; /* transport methods */
143 struct socket * sock; /* BSD socket layer */
144 struct sock * inet; /* INET layer */
146 struct rpc_timeout timeout; /* timeout parms */
147 struct sockaddr_in addr; /* server address */
148 int prot; /* IP protocol */
150 unsigned long cong; /* current congestion */
151 unsigned long cwnd; /* congestion window */
153 unsigned int rcvsize, /* socket receive buffer size */
154 sndsize; /* socket send buffer size */
156 size_t max_payload; /* largest RPC payload size,
159 struct rpc_wait_queue sending; /* requests waiting to send */
160 struct rpc_wait_queue resend; /* requests waiting to resend */
161 struct rpc_wait_queue pending; /* requests in flight */
162 struct rpc_wait_queue backlog; /* waiting for slot */
163 struct list_head free; /* free slots */
164 struct rpc_rqst * slot; /* slot table storage */
165 unsigned int max_reqs; /* total slots */
166 unsigned long state; /* transport state */
167 unsigned char shutdown : 1, /* being shut down */
168 nocong : 1, /* no congestion control */
169 resvport : 1, /* use a reserved port */
170 stream : 1; /* TCP */
175 __u32 xid; /* Next XID value to use */
178 * State of TCP reply receive stuff
180 u32 tcp_recm, /* Fragment header */
181 tcp_xid, /* Current XID */
182 tcp_reclen, /* fragment length */
183 tcp_offset; /* fragment offset */
184 unsigned long tcp_copied, /* copied to request */
187 * Connection of sockets
189 struct work_struct sock_connect;
192 * Disconnection of idle sockets
194 struct work_struct task_cleanup;
195 struct timer_list timer;
196 unsigned long last_used;
201 spinlock_t transport_lock; /* lock transport info */
202 spinlock_t reserve_lock; /* lock slot table */
203 struct rpc_task * snd_task; /* Task blocked in send */
205 struct list_head recv;
208 void (*old_data_ready)(struct sock *, int);
209 void (*old_state_change)(struct sock *);
210 void (*old_write_space)(struct sock *);
212 wait_queue_head_t cong_wait;
215 #define XPRT_LAST_FRAG (1 << 0)
216 #define XPRT_COPY_RECM (1 << 1)
217 #define XPRT_COPY_XID (1 << 2)
218 #define XPRT_COPY_DATA (1 << 3)
222 struct rpc_xprt * xprt_create_proto(int proto, struct sockaddr_in *addr,
223 struct rpc_timeout *toparms);
224 void xprt_disconnect(struct rpc_xprt *);
225 int xprt_destroy(struct rpc_xprt *);
226 void xprt_set_timeout(struct rpc_timeout *, unsigned int,
228 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *, u32);
229 void xprt_complete_rqst(struct rpc_xprt *,
230 struct rpc_rqst *, int);
231 void xprt_reserve(struct rpc_task *);
232 int xprt_prepare_transmit(struct rpc_task *);
233 void xprt_transmit(struct rpc_task *);
234 void xprt_receive(struct rpc_task *);
235 int xprt_adjust_timeout(struct rpc_rqst *req);
236 void xprt_release(struct rpc_task *);
237 void xprt_connect(struct rpc_task *);
238 int xs_setup_udp(struct rpc_xprt *,
239 struct rpc_timeout *);
240 int xs_setup_tcp(struct rpc_xprt *,
241 struct rpc_timeout *);
244 * Reserved bit positions in xprt->state
246 #define XPRT_LOCKED (0)
247 #define XPRT_CONNECTED (1)
248 #define XPRT_CONNECTING (2)
250 static inline void xprt_set_connected(struct rpc_xprt *xprt)
252 set_bit(XPRT_CONNECTED, &xprt->state);
255 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
257 clear_bit(XPRT_CONNECTED, &xprt->state);
260 static inline int xprt_connected(struct rpc_xprt *xprt)
262 return test_bit(XPRT_CONNECTED, &xprt->state);
265 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
267 return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
270 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
272 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
275 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
277 smp_mb__before_clear_bit();
278 clear_bit(XPRT_CONNECTING, &xprt->state);
279 smp_mb__after_clear_bit();
282 static inline int xprt_connecting(struct rpc_xprt *xprt)
284 return test_bit(XPRT_CONNECTING, &xprt->state);
287 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
289 return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
292 #endif /* __KERNEL__*/
294 #endif /* _LINUX_SUNRPC_XPRT_H */