/* * linux/include/linux/sunrpc/xprt.h * * Declarations for the RPC transport interface. * * Copyright (C) 1995, 1996 Olaf Kirch */ #ifndef _LINUX_SUNRPC_XPRT_H #define _LINUX_SUNRPC_XPRT_H #include #include #include #include #include /* * 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. */ extern unsigned int xprt_udp_slot_table_entries; extern unsigned int xprt_tcp_slot_table_entries; #define RPC_MIN_SLOT_TABLE (2U) #define RPC_DEF_SLOT_TABLE (16U) #define RPC_MAX_SLOT_TABLE (128U) #define RPC_CWNDSHIFT (8U) #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) #define RPC_INITCWND RPC_CWNDSCALE #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) #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 transport idle timeout. */ #define RPC_IDLE_DISCONNECT_TIMEOUT (5*60*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_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 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 */ int rq_cong; /* has incremented xprt->cong */ int rq_received; /* receive completed */ u32 rq_seqno; /* gss seq no. used on req. */ struct list_head rq_list; struct xdr_buf rq_private_buf; /* The receive buffer * used in the softirq. */ unsigned long rq_majortimeo; /* major timeout alarm */ unsigned long rq_timeout; /* Current timeout value */ unsigned int rq_retries; /* # of retries */ /* * 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_ntrans; }; #define rq_svec rq_snd_buf.head #define rq_slen rq_snd_buf.len struct rpc_task; struct rpc_xprt; struct rpc_xprt_ops { void (*set_buffer_size)(struct rpc_xprt *xprt); int (*reserve_xprt)(struct rpc_task *task); void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); void (*connect)(struct rpc_task *task); int (*send_request)(struct rpc_task *task); void (*set_retrans_timeout)(struct rpc_task *task); void (*timer)(struct rpc_task *task); void (*close)(struct rpc_xprt *xprt); void (*destroy)(struct rpc_xprt *xprt); }; struct rpc_xprt { struct rpc_xprt_ops * ops; /* transport methods */ 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, /* transport rcv buffer size */ sndsize; /* transport send buffer size */ size_t max_payload; /* largest RPC payload size, in bytes */ unsigned int tsh_size; /* size of transport specific header */ 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 list_head free; /* free slots */ struct rpc_rqst * slot; /* slot table storage */ unsigned int max_reqs; /* total slots */ unsigned long state; /* transport state */ unsigned char shutdown : 1, /* being shut down */ nocong : 1, /* no congestion control */ resvport : 1; /* use a reserved port */ /* * XID */ __u32 xid; /* Next XID value to use */ /* * 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; /* * Connection of transports */ struct work_struct connect_worker; unsigned short port; /* * Disconnection of idle transports */ struct work_struct task_cleanup; struct timer_list timer; unsigned long last_used; /* * Send stuff */ spinlock_t transport_lock; /* lock transport info */ spinlock_t reserve_lock; /* lock slot table */ 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; }; #define XPRT_LAST_FRAG (1 << 0) #define XPRT_COPY_RECM (1 << 1) #define XPRT_COPY_XID (1 << 2) #define XPRT_COPY_DATA (1 << 3) #ifdef __KERNEL__ /* * Transport operations used by ULPs */ struct rpc_xprt * xprt_create_proto(int proto, struct sockaddr_in *addr, struct rpc_timeout *to); void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr); /* * Generic internal transport functions */ void xprt_connect(struct rpc_task *task); void xprt_reserve(struct rpc_task *task); int xprt_reserve_xprt(struct rpc_task *task); int xprt_reserve_xprt_cong(struct rpc_task *task); int xprt_prepare_transmit(struct rpc_task *task); void xprt_transmit(struct rpc_task *task); int xprt_adjust_timeout(struct rpc_rqst *req); void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release(struct rpc_task *task); int xprt_destroy(struct rpc_xprt *xprt); static inline u32 *xprt_skip_transport_header(struct rpc_xprt *xprt, u32 *p) { return p + xprt->tsh_size; } /* * Transport switch helper functions */ void xprt_set_retrans_timeout_def(struct rpc_task *task); void xprt_set_retrans_timeout_rtt(struct rpc_task *task); void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); void xprt_wait_for_buffer_space(struct rpc_task *task); void xprt_write_space(struct rpc_xprt *xprt); void xprt_update_rtt(struct rpc_task *task); void xprt_adjust_cwnd(struct rpc_task *task, int result); struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid); void xprt_complete_rqst(struct rpc_task *task, int copied); void xprt_disconnect(struct rpc_xprt *xprt); /* * Socket transport setup operations */ int xs_setup_udp(struct rpc_xprt *xprt, struct rpc_timeout *to); int xs_setup_tcp(struct rpc_xprt *xprt, struct rpc_timeout *to); /* * Reserved bit positions in xprt->state */ #define XPRT_LOCKED (0) #define XPRT_CONNECTED (1) #define XPRT_CONNECTING (2) static inline void xprt_set_connected(struct rpc_xprt *xprt) { set_bit(XPRT_CONNECTED, &xprt->state); } static inline void xprt_clear_connected(struct rpc_xprt *xprt) { clear_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_connected(struct rpc_xprt *xprt) { return test_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) { return test_and_set_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) { return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); } static inline void xprt_clear_connecting(struct rpc_xprt *xprt) { smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTING, &xprt->state); smp_mb__after_clear_bit(); } static inline int xprt_connecting(struct rpc_xprt *xprt) { return test_bit(XPRT_CONNECTING, &xprt->state); } static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) { return test_and_set_bit(XPRT_CONNECTING, &xprt->state); } #endif /* __KERNEL__*/ #endif /* _LINUX_SUNRPC_XPRT_H */