kernel-fxtec-pro1x/include/linux/sunrpc/xprt.h
Trond Myklebust 7c1d71cf56 SUNRPC: Don't disconnect more than once if retransmitting NFSv4 requests
NFSv4 requires us to ensure that we break the TCP connection before we're
allowed to retransmit a request. However in the case where we're
retransmitting several requests that have been sent on the same
connection, we need to ensure that we don't interfere with the attempt to
reconnect and/or break the connection again once it has been established.

We therefore introduce a 'connection' cookie that is bumped every time a
connection is broken. This allows requests to track if they need to force a
disconnection.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:55:12 -04:00

335 lines
9.6 KiB
C

/*
* linux/include/linux/sunrpc/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/kref.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/msg_prot.h>
#ifdef __KERNEL__
#define RPC_MIN_SLOT_TABLE (2U)
#define RPC_DEF_SLOT_TABLE (16U)
#define RPC_MAX_SLOT_TABLE (128U)
/*
* 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;
};
enum rpc_display_format_t {
RPC_DISPLAY_ADDR = 0,
RPC_DISPLAY_PORT,
RPC_DISPLAY_PROTO,
RPC_DISPLAY_ALL,
RPC_DISPLAY_HEX_ADDR,
RPC_DISPLAY_HEX_PORT,
RPC_DISPLAY_UNIVERSAL_ADDR,
RPC_DISPLAY_NETID,
RPC_DISPLAY_MAX,
};
struct rpc_task;
struct rpc_xprt;
struct seq_file;
/*
* 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 */
__be32 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. */
int rq_enc_pages_num;
struct page **rq_enc_pages; /* scratch pages for use by
gss privacy code */
void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
struct list_head rq_list;
__u32 * rq_buffer; /* XDR encode buffer */
size_t rq_bufsize,
rq_callsize,
rq_rcvsize;
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 */
unsigned int rq_connect_cookie;
/* A cookie used to track the
state of the transport
connection */
/*
* 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_xprt_ops {
void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
int (*reserve_xprt)(struct rpc_task *task);
void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
void (*rpcbind)(struct rpc_task *task);
void (*set_port)(struct rpc_xprt *xprt, unsigned short port);
void (*connect)(struct rpc_task *task);
void * (*buf_alloc)(struct rpc_task *task, size_t size);
void (*buf_free)(void *buffer);
int (*send_request)(struct rpc_task *task);
void (*set_retrans_timeout)(struct rpc_task *task);
void (*timer)(struct rpc_task *task);
void (*release_request)(struct rpc_task *task);
void (*close)(struct rpc_xprt *xprt);
void (*destroy)(struct rpc_xprt *xprt);
void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
};
struct rpc_xprt {
struct kref kref; /* Reference count */
struct rpc_xprt_ops * ops; /* transport methods */
const struct rpc_timeout *timeout; /* timeout parms */
struct sockaddr_storage addr; /* server address */
size_t addrlen; /* size of server address */
int prot; /* IP protocol */
unsigned long cong; /* current congestion */
unsigned long cwnd; /* congestion window */
size_t max_payload; /* largest RPC payload size,
in bytes */
unsigned int tsh_size; /* size of transport specific
header */
struct rpc_wait_queue binding; /* requests waiting on rpcbind */
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 */
resvport : 1; /* use a reserved port */
unsigned int bind_index; /* bind function index */
/*
* Connection of transports
*/
unsigned long connect_timeout,
bind_timeout,
reestablish_timeout;
unsigned int connect_cookie; /* A cookie that gets bumped
every time the transport
is reconnected */
/*
* Disconnection of idle transports
*/
struct work_struct task_cleanup;
struct timer_list timer;
unsigned long last_used,
idle_timeout;
/*
* Send stuff
*/
spinlock_t transport_lock; /* lock transport info */
spinlock_t reserve_lock; /* lock slot table */
u32 xid; /* Next XID value to use */
struct rpc_task * snd_task; /* Task blocked in send */
struct list_head recv;
struct {
unsigned long bind_count, /* total number of binds */
connect_count, /* total number of connects */
connect_start, /* connect start timestamp */
connect_time, /* jiffies waiting for connect */
sends, /* how many complete requests */
recvs, /* how many complete requests */
bad_xids; /* lookup_rqst didn't find XID */
unsigned long long req_u, /* average requests on the wire */
bklog_u; /* backlog queue utilization */
} stat;
const char *address_strings[RPC_DISPLAY_MAX];
};
struct xprt_create {
int ident; /* XPRT_TRANSPORT identifier */
struct sockaddr * srcaddr; /* optional local address */
struct sockaddr * dstaddr; /* remote peer address */
size_t addrlen;
};
struct xprt_class {
struct list_head list;
int ident; /* XPRT_TRANSPORT identifier */
struct rpc_xprt * (*setup)(struct xprt_create *);
struct module *owner;
char name[32];
};
/*
* Generic internal transport functions
*/
struct rpc_xprt *xprt_create_transport(struct xprt_create *args);
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);
void xprt_end_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);
struct rpc_xprt * xprt_get(struct rpc_xprt *xprt);
void xprt_put(struct rpc_xprt *xprt);
static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
{
return p + xprt->tsh_size;
}
/*
* Transport switch helper functions
*/
int xprt_register_transport(struct xprt_class *type);
int xprt_unregister_transport(struct xprt_class *type);
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, rpc_action action);
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, __be32 xid);
void xprt_complete_rqst(struct rpc_task *task, int copied);
void xprt_release_rqst_cong(struct rpc_task *task);
void xprt_disconnect_done(struct rpc_xprt *xprt);
void xprt_force_disconnect(struct rpc_xprt *xprt);
void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
/*
* Reserved bit positions in xprt->state
*/
#define XPRT_LOCKED (0)
#define XPRT_CONNECTED (1)
#define XPRT_CONNECTING (2)
#define XPRT_CLOSE_WAIT (3)
#define XPRT_BOUND (4)
#define XPRT_BINDING (5)
#define XPRT_CLOSING (6)
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);
}
static inline void xprt_set_bound(struct rpc_xprt *xprt)
{
test_and_set_bit(XPRT_BOUND, &xprt->state);
}
static inline int xprt_bound(struct rpc_xprt *xprt)
{
return test_bit(XPRT_BOUND, &xprt->state);
}
static inline void xprt_clear_bound(struct rpc_xprt *xprt)
{
clear_bit(XPRT_BOUND, &xprt->state);
}
static inline void xprt_clear_binding(struct rpc_xprt *xprt)
{
smp_mb__before_clear_bit();
clear_bit(XPRT_BINDING, &xprt->state);
smp_mb__after_clear_bit();
}
static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
{
return test_and_set_bit(XPRT_BINDING, &xprt->state);
}
#endif /* __KERNEL__*/
#endif /* _LINUX_SUNRPC_XPRT_H */