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/*
* linux/include/linux/sunrpc/clnt_xprt.h
*
* Declarations for the RPC transport interface.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#ifndef _LINUX_SUNRPC_XPRT_H
#define _LINUX_SUNRPC_XPRT_H
#include <linux/uio.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xdr.h>
/*
* The transport code maintains an estimate on the maximum number of out-
* standing RPC requests, using a smoothed version of the congestion
* avoidance implemented in 44BSD. This is basically the Van Jacobson
* congestion algorithm: If a retransmit occurs, the congestion window is
* halved; otherwise, it is incremented by 1/cwnd when
*
* - a reply is received and
* - a full number of requests are outstanding and
* - the congestion window hasn't been updated recently.
*
* Upper procedures may check whether a request would block waiting for
* a free RPC slot by using the RPC_CONGESTED() macro.
*
* Note: on machines with low memory we should probably use a smaller
* MAXREQS value: At 32 outstanding reqs with 8 megs of RAM, fragment
* reassembly will frequently run out of memory.
*/
#define RPC_MAXCONG (16)
#define RPC_MAXREQS RPC_MAXCONG
#define RPC_CWNDSCALE (256)
#define RPC_MAXCWND (RPC_MAXCONG * RPC_CWNDSCALE)
#define RPC_INITCWND RPC_CWNDSCALE
#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
/* Default timeout values */
#define RPC_MAX_UDP_TIMEOUT (60*HZ)
#define RPC_MAX_TCP_TIMEOUT (600*HZ)
/*
* Wait duration for an RPC TCP connection to be established. Solaris
* NFS over TCP uses 60 seconds, for example, which is in line with how
* long a server takes to reboot.
*/
#define RPC_CONNECT_TIMEOUT (60*HZ)
/*
* Delay an arbitrary number of seconds before attempting to reconnect
* after an error.
*/
#define RPC_REESTABLISH_TIMEOUT (15*HZ)
/* RPC call and reply header size as number of 32bit words (verifier
* size computed separately)
*/
#define RPC_CALLHDRSIZE 6
#define RPC_REPHDRSIZE 4
/*
* This describes a timeout strategy
*/
struct rpc_timeout {
unsigned long to_current, /* current timeout */
to_initval, /* initial timeout */
to_maxval, /* max timeout */
to_increment; /* if !exponential */
unsigned int to_retries; /* max # of retries */
unsigned char to_exponential;
};
/*
* This describes a complete RPC request
*/
struct rpc_rqst {
/*
* This is the user-visible part
*/
struct rpc_xprt * rq_xprt; /* RPC client */
struct rpc_timeout rq_timeout; /* timeout parms */
struct xdr_buf rq_snd_buf; /* send buffer */
struct xdr_buf rq_rcv_buf; /* recv buffer */
/*
* This is the private part
*/
struct rpc_task * rq_task; /* RPC task data */
__u32 rq_xid; /* request XID */
struct rpc_rqst * rq_next; /* free list */
int rq_cong; /* has incremented xprt->cong */
int rq_received; /* receive completed */
struct list_head rq_list;
struct xdr_buf rq_private_buf; /* The receive buffer
* used in the softirq.
*/
/*
* For authentication (e.g. auth_des)
*/
u32 rq_creddata[2];
/*
* Partial send handling
*/
u32 rq_bytes_sent; /* Bytes we have sent */
unsigned long rq_xtime; /* when transmitted */
int rq_ntimeo;
int rq_ntrans;
};
#define rq_svec rq_snd_buf.head
#define rq_slen rq_snd_buf.len
#define rq_rvec rq_rcv_buf.head
#define rq_rlen rq_rcv_buf.len
#define XPRT_LAST_FRAG (1 << 0)
#define XPRT_COPY_RECM (1 << 1)
#define XPRT_COPY_XID (1 << 2)
#define XPRT_COPY_DATA (1 << 3)
struct rpc_xprt {
struct socket * sock; /* BSD socket layer */
struct sock * inet; /* INET layer */
struct rpc_timeout timeout; /* timeout parms */
struct sockaddr_in addr; /* server address */
int prot; /* IP protocol */
unsigned long cong; /* current congestion */
unsigned long cwnd; /* congestion window */
unsigned int rcvsize, /* socket receive buffer size */
sndsize; /* socket send buffer size */
struct rpc_wait_queue sending; /* requests waiting to send */
struct rpc_wait_queue resend; /* requests waiting to resend */
struct rpc_wait_queue pending; /* requests in flight */
struct rpc_wait_queue backlog; /* waiting for slot */
struct rpc_rqst * free; /* free slots */
struct rpc_rqst slot[RPC_MAXREQS];
unsigned long sockstate; /* Socket state */
unsigned char shutdown : 1, /* being shut down */
nocong : 1, /* no congestion control */
resvport : 1, /* use a reserved port */
stream : 1; /* TCP */
/*
* State of TCP reply receive stuff
*/
u32 tcp_recm, /* Fragment header */
tcp_xid, /* Current XID */
tcp_reclen, /* fragment length */
tcp_offset; /* fragment offset */
unsigned long tcp_copied, /* copied to request */
tcp_flags;
/*
* Send stuff
*/
spinlock_t sock_lock; /* lock socket info */
spinlock_t xprt_lock; /* lock xprt info */
struct rpc_task * snd_task; /* Task blocked in send */
struct list_head recv;
void (*old_data_ready)(struct sock *, int);
void (*old_state_change)(struct sock *);
void (*old_write_space)(struct sock *);
wait_queue_head_t cong_wait;
};
#ifdef __KERNEL__
struct rpc_xprt * xprt_create_proto(int proto, struct sockaddr_in *addr,
struct rpc_timeout *toparms);
int xprt_destroy(struct rpc_xprt *);
void xprt_shutdown(struct rpc_xprt *);
void xprt_default_timeout(struct rpc_timeout *, int);
void xprt_set_timeout(struct rpc_timeout *, unsigned int,
unsigned long);
void xprt_reserve(struct rpc_task *);
int xprt_prepare_transmit(struct rpc_task *);
void xprt_transmit(struct rpc_task *);
void xprt_receive(struct rpc_task *);
int xprt_adjust_timeout(struct rpc_timeout *);
void xprt_release(struct rpc_task *);
void xprt_connect(struct rpc_task *);
int xprt_clear_backlog(struct rpc_xprt *);
void xprt_sock_setbufsize(struct rpc_xprt *);
#define XPRT_CONNECT 0
#define xprt_connected(xp) (test_bit(XPRT_CONNECT, &(xp)->sockstate))
#define xprt_set_connected(xp) (set_bit(XPRT_CONNECT, &(xp)->sockstate))
#define xprt_test_and_set_connected(xp) (test_and_set_bit(XPRT_CONNECT, &(xp)->sockstate))
#define xprt_clear_connected(xp) (clear_bit(XPRT_CONNECT, &(xp)->sockstate))
#endif /* __KERNEL__*/
#endif /* _LINUX_SUNRPC_XPRT_H */