Merge branch 'master'

1 files changed, 447 insertions, 1166 deletions

diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 3c654e06b08..6dda3860351 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -10,12 +10,12 @@
  *	one is available. Otherwise, it sleeps on the backlog queue
  *	(xprt_reserve).
  *  -	Next, the caller puts together the RPC message, stuffs it into
- *	the request struct, and calls xprt_call().
- *  -	xprt_call transmits the message and installs the caller on the
- *	socket's wait list. At the same time, it installs a timer that
+ *	the request struct, and calls xprt_transmit().
+ *  -	xprt_transmit sends the message and installs the caller on the
+ *	transport's wait list. At the same time, it installs a timer that
  *	is run after the packet's timeout has expired.
  *  -	When a packet arrives, the data_ready handler walks the list of
- *	pending requests for that socket. If a matching XID is found, the
+ *	pending requests for that transport. If a matching XID is found, the
  *	caller is woken up, and the timer removed.
  *  -	When no reply arrives within the timeout interval, the timer is
  *	fired by the kernel and runs xprt_timer(). It either adjusts the
@@ -33,36 +33,17 @@
  *
  *  Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de>
  *
- *  TCP callback races fixes (C) 1998 Red Hat Software <alan@redhat.com>
- *  TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com>
- *  TCP NFS related read + write fixes
- *   (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
- *
- *  Rewrite of larges part of the code in order to stabilize TCP stuff.
- *  Fix behaviour when socket buffer is full.
- *   (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
+ *  Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com>
  */
 
+#include <linux/module.h>
+
 #include <linux/types.h>
-#include <linux/slab.h>
-#include <linux/capability.h>
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/socket.h>
-#include <linux/in.h>
-#include <linux/net.h>
-#include <linux/mm.h>
-#include <linux/udp.h>
-#include <linux/tcp.h>
-#include <linux/sunrpc/clnt.h>
-#include <linux/file.h>
+#include <linux/interrupt.h>
 #include <linux/workqueue.h>
 #include <linux/random.h>
 
-#include <net/sock.h>
-#include <net/checksum.h>
-#include <net/udp.h>
-#include <net/tcp.h>
+#include <linux/sunrpc/clnt.h>
 
 /*
  * Local variables
@@ -73,81 +54,90 @@
 # define RPCDBG_FACILITY	RPCDBG_XPRT
 #endif
 
-#define XPRT_MAX_BACKOFF	(8)
-#define XPRT_IDLE_TIMEOUT	(5*60*HZ)
-#define XPRT_MAX_RESVPORT	(800)
-
 /*
  * Local functions
  */
 static void	xprt_request_init(struct rpc_task *, struct rpc_xprt *);
 static inline void	do_xprt_reserve(struct rpc_task *);
-static void	xprt_disconnect(struct rpc_xprt *);
 static void	xprt_connect_status(struct rpc_task *task);
-static struct rpc_xprt * xprt_setup(int proto, struct sockaddr_in *ap,
-						struct rpc_timeout *to);
-static struct socket *xprt_create_socket(struct rpc_xprt *, int, int);
-static void	xprt_bind_socket(struct rpc_xprt *, struct socket *);
 static int      __xprt_get_cong(struct rpc_xprt *, struct rpc_task *);
 
-static int	xprt_clear_backlog(struct rpc_xprt *xprt);
-
-#ifdef RPC_DEBUG_DATA
 /*
- * Print the buffer contents (first 128 bytes only--just enough for
- * diropres return).
+ * 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.
  */
-static void
-xprt_pktdump(char *msg, u32 *packet, unsigned int count)
-{
-	u8	*buf = (u8 *) packet;
-	int	j;
-
-	dprintk("RPC:      %s\n", msg);
-	for (j = 0; j < count && j < 128; j += 4) {
-		if (!(j & 31)) {
-			if (j)
-				dprintk("\n");
-			dprintk("0x%04x ", j);
-		}
-		dprintk("%02x%02x%02x%02x ",
-			buf[j], buf[j+1], buf[j+2], buf[j+3]);
-	}
-	dprintk("\n");
-}
-#else
-static inline void
-xprt_pktdump(char *msg, u32 *packet, unsigned int count)
-{
-	/* NOP */
-}
-#endif
+#define RPC_CWNDSHIFT		(8U)
+#define RPC_CWNDSCALE		(1U << RPC_CWNDSHIFT)
+#define RPC_INITCWND		RPC_CWNDSCALE
+#define RPC_MAXCWND(xprt)	((xprt)->max_reqs << RPC_CWNDSHIFT)
 
-/*
- * Look up RPC transport given an INET socket
+#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
+
+/**
+ * xprt_reserve_xprt - serialize write access to transports
+ * @task: task that is requesting access to the transport
+ *
+ * This prevents mixing the payload of separate requests, and prevents
+ * transport connects from colliding with writes.  No congestion control
+ * is provided.
  */
-static inline struct rpc_xprt *
-xprt_from_sock(struct sock *sk)
+int xprt_reserve_xprt(struct rpc_task *task)
 {
-	return (struct rpc_xprt *) sk->sk_user_data;
+	struct rpc_xprt	*xprt = task->tk_xprt;
+	struct rpc_rqst *req = task->tk_rqstp;
+
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
+		if (task == xprt->snd_task)
+			return 1;
+		if (task == NULL)
+			return 0;
+		goto out_sleep;
+	}
+	xprt->snd_task = task;
+	if (req) {
+		req->rq_bytes_sent = 0;
+		req->rq_ntrans++;
+	}
+	return 1;
+
+out_sleep:
+	dprintk("RPC: %4d failed to lock transport %p\n",
+			task->tk_pid, xprt);
+	task->tk_timeout = 0;
+	task->tk_status = -EAGAIN;
+	if (req && req->rq_ntrans)
+		rpc_sleep_on(&xprt->resend, task, NULL, NULL);
+	else
+		rpc_sleep_on(&xprt->sending, task, NULL, NULL);
+	return 0;
 }
 
 /*
- * Serialize write access to sockets, in order to prevent different
- * requests from interfering with each other.
- * Also prevents TCP socket connects from colliding with writes.
+ * xprt_reserve_xprt_cong - serialize write access to transports
+ * @task: task that is requesting access to the transport
+ *
+ * Same as xprt_reserve_xprt, but Van Jacobson congestion control is
+ * integrated into the decision of whether a request is allowed to be
+ * woken up and given access to the transport.
  */
-static int
-__xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
+int xprt_reserve_xprt_cong(struct rpc_task *task)
 {
+	struct rpc_xprt	*xprt = task->tk_xprt;
 	struct rpc_rqst *req = task->tk_rqstp;
 
-	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) {
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
 		if (task == xprt->snd_task)
 			return 1;
 		goto out_sleep;
 	}
-	if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+	if (__xprt_get_cong(xprt, task)) {
 		xprt->snd_task = task;
 		if (req) {
 			req->rq_bytes_sent = 0;
@@ -156,10 +146,10 @@ __xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
 		return 1;
 	}
 	smp_mb__before_clear_bit();
-	clear_bit(XPRT_LOCKED, &xprt->sockstate);
+	clear_bit(XPRT_LOCKED, &xprt->state);
 	smp_mb__after_clear_bit();
 out_sleep:
-	dprintk("RPC: %4d failed to lock socket %p\n", task->tk_pid, xprt);
+	dprintk("RPC: %4d failed to lock transport %p\n", task->tk_pid, xprt);
 	task->tk_timeout = 0;
 	task->tk_status = -EAGAIN;
 	if (req && req->rq_ntrans)
@@ -169,26 +159,52 @@ out_sleep:
 	return 0;
 }
 
-static inline int
-xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
+static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
 {
 	int retval;
 
-	spin_lock_bh(&xprt->sock_lock);
-	retval = __xprt_lock_write(xprt, task);
-	spin_unlock_bh(&xprt->sock_lock);
+	spin_lock_bh(&xprt->transport_lock);
+	retval = xprt->ops->reserve_xprt(task);
+	spin_unlock_bh(&xprt->transport_lock);
 	return retval;
 }
 
+static void __xprt_lock_write_next(struct rpc_xprt *xprt)
+{
+	struct rpc_task *task;
+	struct rpc_rqst *req;
 
-static void
-__xprt_lock_write_next(struct rpc_xprt *xprt)
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
+		return;
+
+	task = rpc_wake_up_next(&xprt->resend);
+	if (!task) {
+		task = rpc_wake_up_next(&xprt->sending);
+		if (!task)
+			goto out_unlock;
+	}
+
+	req = task->tk_rqstp;
+	xprt->snd_task = task;
+	if (req) {
+		req->rq_bytes_sent = 0;
+		req->rq_ntrans++;
+	}
+	return;
+
+out_unlock:
+	smp_mb__before_clear_bit();
+	clear_bit(XPRT_LOCKED, &xprt->state);
+	smp_mb__after_clear_bit();
+}
+
+static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
 {
 	struct rpc_task *task;
 
-	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
 		return;
-	if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
+	if (RPCXPRT_CONGESTED(xprt))
 		goto out_unlock;
 	task = rpc_wake_up_next(&xprt->resend);
 	if (!task) {
@@ -196,7 +212,7 @@ __xprt_lock_write_next(struct rpc_xprt *xprt)
 		if (!task)
 			goto out_unlock;
 	}
-	if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+	if (__xprt_get_cong(xprt, task)) {
 		struct rpc_rqst *req = task->tk_rqstp;
 		xprt->snd_task = task;
 		if (req) {
@@ -207,87 +223,52 @@ __xprt_lock_write_next(struct rpc_xprt *xprt)
 	}
 out_unlock:
 	smp_mb__before_clear_bit();
-	clear_bit(XPRT_LOCKED, &xprt->sockstate);
+	clear_bit(XPRT_LOCKED, &xprt->state);
 	smp_mb__after_clear_bit();
 }
 
-/*
- * Releases the socket for use by other requests.
+/**
+ * xprt_release_xprt - allow other requests to use a transport
+ * @xprt: transport with other tasks potentially waiting
+ * @task: task that is releasing access to the transport
+ *
+ * Note that "task" can be NULL.  No congestion control is provided.
  */
-static void
-__xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
+void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 {
 	if (xprt->snd_task == task) {
 		xprt->snd_task = NULL;
 		smp_mb__before_clear_bit();
-		clear_bit(XPRT_LOCKED, &xprt->sockstate);
+		clear_bit(XPRT_LOCKED, &xprt->state);
 		smp_mb__after_clear_bit();
 		__xprt_lock_write_next(xprt);
 	}
 }
 
-static inline void
-xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
-{
-	spin_lock_bh(&xprt->sock_lock);
-	__xprt_release_write(xprt, task);
-	spin_unlock_bh(&xprt->sock_lock);
-}
-
-/*
- * Write data to socket.
+/**
+ * xprt_release_xprt_cong - allow other requests to use a transport
+ * @xprt: transport with other tasks potentially waiting
+ * @task: task that is releasing access to the transport
+ *
+ * Note that "task" can be NULL.  Another task is awoken to use the
+ * transport if the transport's congestion window allows it.
  */
-static inline int
-xprt_sendmsg(struct rpc_xprt *xprt, struct rpc_rqst *req)
+void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
 {
-	struct socket	*sock = xprt->sock;
-	struct xdr_buf	*xdr = &req->rq_snd_buf;
-	struct sockaddr *addr = NULL;
-	int addrlen = 0;
-	unsigned int	skip;
-	int		result;
-
-	if (!sock)
-		return -ENOTCONN;
-
-	xprt_pktdump("packet data:",
-				req->rq_svec->iov_base,
-				req->rq_svec->iov_len);
-
-	/* For UDP, we need to provide an address */
-	if (!xprt->stream) {
-		addr = (struct sockaddr *) &xprt->addr;
-		addrlen = sizeof(xprt->addr);
+	if (xprt->snd_task == task) {
+		xprt->snd_task = NULL;
+		smp_mb__before_clear_bit();
+		clear_bit(XPRT_LOCKED, &xprt->state);
+		smp_mb__after_clear_bit();
+		__xprt_lock_write_next_cong(xprt);
 	}
-	/* Dont repeat bytes */
-	skip = req->rq_bytes_sent;
-
-	clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
-	result = xdr_sendpages(sock, addr, addrlen, xdr, skip, MSG_DONTWAIT);
-
-	dprintk("RPC:      xprt_sendmsg(%d) = %d\n", xdr->len - skip, result);
-
-	if (result >= 0)
-		return result;
+}
 
-	switch (result) {
-	case -ECONNREFUSED:
-		/* When the server has died, an ICMP port unreachable message
-		 * prompts ECONNREFUSED.
-		 */
-	case -EAGAIN:
-		break;
-	case -ECONNRESET:
-	case -ENOTCONN:
-	case -EPIPE:
-		/* connection broken */
-		if (xprt->stream)
-			result = -ENOTCONN;
-		break;
-	default:
-		printk(KERN_NOTICE "RPC: sendmsg returned error %d\n", -result);
-	}
-	return result;
+static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+	spin_lock_bh(&xprt->transport_lock);
+	xprt->ops->release_xprt(xprt, task);
+	spin_unlock_bh(&xprt->transport_lock);
 }
 
 /*
@@ -321,26 +302,40 @@ __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req)
 		return;
 	req->rq_cong = 0;
 	xprt->cong -= RPC_CWNDSCALE;
-	__xprt_lock_write_next(xprt);
+	__xprt_lock_write_next_cong(xprt);
 }
 
-/*
- * Adjust RPC congestion window
+/**
+ * xprt_release_rqst_cong - housekeeping when request is complete
+ * @task: RPC request that recently completed
+ *
+ * Useful for transports that require congestion control.
+ */
+void xprt_release_rqst_cong(struct rpc_task *task)
+{
+	__xprt_put_cong(task->tk_xprt, task->tk_rqstp);
+}
+
+/**
+ * xprt_adjust_cwnd - adjust transport congestion window
+ * @task: recently completed RPC request used to adjust window
+ * @result: result code of completed RPC request
+ *
  * We use a time-smoothed congestion estimator to avoid heavy oscillation.
  */
-static void
-xprt_adjust_cwnd(struct rpc_xprt *xprt, int result)
+void xprt_adjust_cwnd(struct rpc_task *task, int result)
 {
-	unsigned long	cwnd;
+	struct rpc_rqst *req = task->tk_rqstp;
+	struct rpc_xprt *xprt = task->tk_xprt;
+	unsigned long cwnd = xprt->cwnd;
 
-	cwnd = xprt->cwnd;
 	if (result >= 0 && cwnd <= xprt->cong) {
 		/* The (cwnd >> 1) term makes sure
 		 * the result gets rounded properly. */
 		cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd;
 		if (cwnd > RPC_MAXCWND(xprt))
 			cwnd = RPC_MAXCWND(xprt);
-		__xprt_lock_write_next(xprt);
+		__xprt_lock_write_next_cong(xprt);
 	} else if (result == -ETIMEDOUT) {
 		cwnd >>= 1;
 		if (cwnd < RPC_CWNDSCALE)
@@ -349,11 +344,89 @@ xprt_adjust_cwnd(struct rpc_xprt *xprt, int result)
 	dprintk("RPC:      cong %ld, cwnd was %ld, now %ld\n",
 			xprt->cong, xprt->cwnd, cwnd);
 	xprt->cwnd = cwnd;
+	__xprt_put_cong(xprt, req);
+}
+
+/**
+ * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue
+ * @xprt: transport with waiting tasks
+ * @status: result code to plant in each task before waking it
+ *
+ */
+void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status)
+{
+	if (status < 0)
+		rpc_wake_up_status(&xprt->pending, status);
+	else
+		rpc_wake_up(&xprt->pending);
+}
+
+/**
+ * xprt_wait_for_buffer_space - wait for transport output buffer to clear
+ * @task: task to be put to sleep
+ *
+ */
+void xprt_wait_for_buffer_space(struct rpc_task *task)
+{
+	struct rpc_rqst *req = task->tk_rqstp;
+	struct rpc_xprt *xprt = req->rq_xprt;
+
+	task->tk_timeout = req->rq_timeout;
+	rpc_sleep_on(&xprt->pending, task, NULL, NULL);
+}
+
+/**
+ * xprt_write_space - wake the task waiting for transport output buffer space
+ * @xprt: transport with waiting tasks
+ *
+ * Can be called in a soft IRQ context, so xprt_write_space never sleeps.
+ */
+void xprt_write_space(struct rpc_xprt *xprt)
+{
+	if (unlikely(xprt->shutdown))
+		return;
+
+	spin_lock_bh(&xprt->transport_lock);
+	if (xprt->snd_task) {
+		dprintk("RPC:      write space: waking waiting task on xprt %p\n",
+				xprt);
+		rpc_wake_up_task(xprt->snd_task);
+	}
+	spin_unlock_bh(&xprt->transport_lock);
+}
+
+/**
+ * xprt_set_retrans_timeout_def - set a request's retransmit timeout
+ * @task: task whose timeout is to be set
+ *
+ * Set a request's retransmit timeout based on the transport's
+ * default timeout parameters.  Used by transports that don't adjust
+ * the retransmit timeout based on round-trip time estimation.
+ */
+void xprt_set_retrans_timeout_def(struct rpc_task *task)
+{
+	task->tk_timeout = task->tk_rqstp->rq_timeout;
 }
 
 /*
- * Reset the major timeout value
+ * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout
+ * @task: task whose timeout is to be set
+ * 
+ * Set a request's retransmit timeout using the RTT estimator.
  */
+void xprt_set_retrans_timeout_rtt(struct rpc_task *task)
+{
+	int timer = task->tk_msg.rpc_proc->p_timer;
+	struct rpc_rtt *rtt = task->tk_client->cl_rtt;
+	struct rpc_rqst *req = task->tk_rqstp;
+	unsigned long max_timeout = req->rq_xprt->timeout.to_maxval;
+
+	task->tk_timeout = rpc_calc_rto(rtt, timer);
+	task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries;
+	if (task->tk_timeout > max_timeout || task->tk_timeout == 0)
+		task->tk_timeout = max_timeout;
+}
+
 static void xprt_reset_majortimeo(struct rpc_rqst *req)
 {
 	struct rpc_timeout *to = &req->rq_xprt->timeout;
@@ -368,8 +441,10 @@ static void xprt_reset_majortimeo(struct rpc_rqst *req)
 	req->rq_majortimeo += jiffies;
 }
 
-/*
- * Adjust timeout values etc for next retransmit
+/**
+ * xprt_adjust_timeout - adjust timeout values for next retransmit
+ * @req: RPC request containing parameters to use for the adjustment
+ *
  */
 int xprt_adjust_timeout(struct rpc_rqst *req)
 {
@@ -391,9 +466,9 @@ int xprt_adjust_timeout(struct rpc_rqst *req)
 		req->rq_retries = 0;
 		xprt_reset_majortimeo(req);
 		/* Reset the RTT counters == "slow start" */
-		spin_lock_bh(&xprt->sock_lock);
+		spin_lock_bh(&xprt->transport_lock);
 		rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
-		spin_unlock_bh(&xprt->sock_lock);
+		spin_unlock_bh(&xprt->transport_lock);
 		pprintk("RPC: %lu timeout\n", jiffies);
 		status = -ETIMEDOUT;
 	}
@@ -405,133 +480,52 @@ int xprt_adjust_timeout(struct rpc_rqst *req)
 	return status;
 }
 
-/*
- * Close down a transport socket
- */
-static void
-xprt_close(struct rpc_xprt *xprt)
-{
-	struct socket	*sock = xprt->sock;
-	struct sock	*sk = xprt->inet;
-
-	if (!sk)
-		return;
-
-	write_lock_bh(&sk->sk_callback_lock);
-	xprt->inet = NULL;
-	xprt->sock = NULL;
-
-	sk->sk_user_data    = NULL;
-	sk->sk_data_ready   = xprt->old_data_ready;
-	sk->sk_state_change = xprt->old_state_change;
-	sk->sk_write_space  = xprt->old_write_space;
-	write_unlock_bh(&sk->sk_callback_lock);
-
-	sk->sk_no_check	 = 0;
-
-	sock_release(sock);
-}
-
-static void
-xprt_socket_autoclose(void *args)
+static void xprt_autoclose(void *args)
 {
 	struct rpc_xprt *xprt = (struct rpc_xprt *)args;
 
 	xprt_disconnect(xprt);
-	xprt_close(xprt);
+	xprt->ops->close(xprt);
 	xprt_release_write(xprt, NULL);
 }
 
-/*
- * Mark a transport as disconnected
+/**
+ * xprt_disconnect - mark a transport as disconnected
+ * @xprt: transport to flag for disconnect
+ *
  */
-static void
-xprt_disconnect(struct rpc_xprt *xprt)
+void xprt_disconnect(struct rpc_xprt *xprt)
 {
 	dprintk("RPC:      disconnected transport %p\n", xprt);
-	spin_lock_bh(&xprt->sock_lock);
+	spin_lock_bh(&xprt->transport_lock);
 	xprt_clear_connected(xprt);
-	rpc_wake_up_status(&xprt->pending, -ENOTCONN);
-	spin_unlock_bh(&xprt->sock_lock);
+	xprt_wake_pending_tasks(xprt, -ENOTCONN);
+	spin_unlock_bh(&xprt->transport_lock);
 }
 
-/*
- * Used to allow disconnection when we've been idle
- */
 static void
 xprt_init_autodisconnect(unsigned long data)
 {
 	struct rpc_xprt *xprt = (struct rpc_xprt *)data;
 
-	spin_lock(&xprt->sock_lock);
+	spin_lock(&xprt->transport_lock);
 	if (!list_empty(&xprt->recv) || xprt->shutdown)
 		goto out_abort;
-	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
 		goto out_abort;
-	spin_unlock(&xprt->sock_lock);
-	/* Let keventd close the socket */
-	if (test_bit(XPRT_CONNECTING, &xprt->sockstate) != 0)
+	spin_unlock(&xprt->transport_lock);
+	if (xprt_connecting(xprt))
 		xprt_release_write(xprt, NULL);
 	else
 		schedule_work(&xprt->task_cleanup);
 	return;
 out_abort:
-	spin_unlock(&xprt->sock_lock);
-}
-
-static void xprt_socket_connect(void *args)
-{
-	struct rpc_xprt *xprt = (struct rpc_xprt *)args;
-	struct socket *sock = xprt->sock;
-	int status = -EIO;
-
-	if (xprt->shutdown || xprt->addr.sin_port == 0)
-		goto out;
-
-	/*
-	 * Start by resetting any existing state
-	 */
-	xprt_close(xprt);
-	sock = xprt_create_socket(xprt, xprt->prot, xprt->resvport);
-	if (sock == NULL) {
-		/* couldn't create socket or bind to reserved port;
-		 * this is likely a permanent error, so cause an abort */
-		goto out;
-	}
-	xprt_bind_socket(xprt, sock);
-	xprt_sock_setbufsize(xprt);
-
-	status = 0;
-	if (!xprt->stream)
-		goto out;
-
-	/*
-	 * Tell the socket layer to start connecting...
-	 */
-	status = sock->ops->connect(sock, (struct sockaddr *) &xprt->addr,
-			sizeof(xprt->addr), O_NONBLOCK);
-	dprintk("RPC: %p  connect status %d connected %d sock state %d\n",
-			xprt, -status, xprt_connected(xprt), sock->sk->sk_state);
-	if (status < 0) {
-		switch (status) {
-			case -EINPROGRESS:
-			case -EALREADY:
-				goto out_clear;
-		}
-	}
-out:
-	if (status < 0)
-		rpc_wake_up_status(&xprt->pending, status);
-	else
-		rpc_wake_up(&xprt->pending);
-out_clear:
-	smp_mb__before_clear_bit();
-	clear_bit(XPRT_CONNECTING, &xprt->sockstate);
-	smp_mb__after_clear_bit();
+	spin_unlock(&xprt->transport_lock);
 }
 
-/*
- * Attempt to connect a TCP socket.
+/**
+ * xprt_connect - schedule a transport connect operation
+ * @task: RPC task that is requesting the connect
  *
  */
 void xprt_connect(struct rpc_task *task)
@@ -552,37 +546,19 @@ void xprt_connect(struct rpc_task *task)
 	if (!xprt_lock_write(xprt, task))
 		return;
 	if (xprt_connected(xprt))
-		goto out_write;
+		xprt_release_write(xprt, task);
+	else {
+		if (task->tk_rqstp)
+			task->tk_rqstp->rq_bytes_sent = 0;
 
-	if (task->tk_rqstp)
-		task->tk_rqstp->rq_bytes_sent = 0;
-
-	task->tk_timeout = RPC_CONNECT_TIMEOUT;
-	rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL);
-	if (!test_and_set_bit(XPRT_CONNECTING, &xprt->sockstate)) {
-		/* Note: if we are here due to a dropped connection
-		 * 	 we delay reconnecting by RPC_REESTABLISH_TIMEOUT/HZ
-		 * 	 seconds
-		 */
-		if (xprt->sock != NULL)
-			schedule_delayed_work(&xprt->sock_connect,
-					RPC_REESTABLISH_TIMEOUT);
-		else {
-			schedule_work(&xprt->sock_connect);
-			if (!RPC_IS_ASYNC(task))
-				flush_scheduled_work();
-		}
+		task->tk_timeout = xprt->connect_timeout;
+		rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL);
+		xprt->ops->connect(task);
 	}
 	return;
- out_write:
-	xprt_release_write(xprt, task);
 }
 
-/*
- * We arrive here when awoken from waiting on connection establishment.
- */
-static void
-xprt_connect_status(struct rpc_task *task)
+static void xprt_connect_status(struct rpc_task *task)
 {
 	struct rpc_xprt	*xprt = task->tk_xprt;
 
@@ -592,31 +568,42 @@ xprt_connect_status(struct rpc_task *task)
 		return;
 	}
 
-	/* if soft mounted, just cause this RPC to fail */
-	if (RPC_IS_SOFT(task))
-		task->tk_status = -EIO;
-
 	switch (task->tk_status) {
 	case -ECONNREFUSED:
 	case -ECONNRESET:
+		dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n",
+				task->tk_pid, task->tk_client->cl_server);
+		break;
 	case -ENOTCONN:
-		return;
+		dprintk("RPC: %4d xprt_connect_status: connection broken\n",
+				task->tk_pid);
+		break;
 	case -ETIMEDOUT:
-		dprintk("RPC: %4d xprt_connect_status: timed out\n",
+		dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n",
 				task->tk_pid);
 		break;
 	default:
-		printk(KERN_ERR "RPC: error %d connecting to server %s\n",
-				-task->tk_status, task->tk_client->cl_server);
+		dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n",
+				task->tk_pid, -task->tk_status, task->tk_client->cl_server);
+		xprt_release_write(xprt, task);
+		task->tk_status = -EIO;
+		return;
+	}
+
+	/* if soft mounted, just cause this RPC to fail */
+	if (RPC_IS_SOFT(task)) {
+		xprt_release_write(xprt, task);
+		task->tk_status = -EIO;
 	}
-	xprt_release_write(xprt, task);
 }
 
-/*
- * Look up the RPC request corresponding to a reply, and then lock it.
+/**
+ * xprt_lookup_rqst - find an RPC request corresponding to an XID
+ * @xprt: transport on which the original request was transmitted
+ * @xid: RPC XID of incoming reply
+ *
  */
-static inline struct rpc_rqst *
-xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
+struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
 {
 	struct list_head *pos;
 	struct rpc_rqst	*req = NULL;
@@ -631,556 +618,68 @@ xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
 	return req;
 }
 
-/*
- * Complete reply received.
- * The TCP code relies on us to remove the request from xprt->pending.
- */
-static void
-xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied)
-{
-	struct rpc_task	*task = req->rq_task;
-	struct rpc_clnt *clnt = task->tk_client;
-
-	/* Adjust congestion window */
-	if (!xprt->nocong) {
-		unsigned timer = task->tk_msg.rpc_proc->p_timer;
-		xprt_adjust_cwnd(xprt, copied);
-		__xprt_put_cong(xprt, req);
-		if (timer) {
-			if (req->rq_ntrans == 1)
-				rpc_update_rtt(clnt->cl_rtt, timer,
-						(long)jiffies - req->rq_xtime);
-			rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1);
-		}
-	}
-
-#ifdef RPC_PROFILE
-	/* Profile only reads for now */
-	if (copied > 1024) {
-		static unsigned long	nextstat;
-		static unsigned long	pkt_rtt, pkt_len, pkt_cnt;
-
-		pkt_cnt++;
-		pkt_len += req->rq_slen + copied;
-		pkt_rtt += jiffies - req->rq_xtime;
-		if (time_before(nextstat, jiffies)) {
-			printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd);
-			printk("RPC: %ld %ld %ld %ld stat\n",
-					jiffies, pkt_cnt, pkt_len, pkt_rtt);
-			pkt_rtt = pkt_len = pkt_cnt = 0;
-			nextstat = jiffies + 5 * HZ;
-		}
-	}
-#endif
-
-	dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied);
-	list_del_init(&req->rq_list);
-	req->rq_received = req->rq_private_buf.len = copied;
-
-	/* ... and wake up the process. */
-	rpc_wake_up_task(task);
-	return;
-}
-
-static size_t
-skb_read_bits(skb_reader_t *desc, void *to, size_t len)
-{
-	if (len > desc->count)
-		len = desc->count;
-	if (skb_copy_bits(desc->skb, desc->offset, to, len))
-		return 0;
-	desc->count -= len;
-	desc->offset += len;
-	return len;
-}
-
-static size_t
-skb_read_and_csum_bits(skb_reader_t *desc, void *to, size_t len)
-{
-	unsigned int csum2, pos;
-
-	if (len > desc->count)
-		len = desc->count;
-	pos = desc->offset;
-	csum2 = skb_copy_and_csum_bits(desc->skb, pos, to, len, 0);
-	desc->csum = csum_block_add(desc->csum, csum2, pos);
-	desc->count -= len;
-	desc->offset += len;
-	return len;
-}
-
-/*
- * We have set things up such that we perform the checksum of the UDP
- * packet in parallel with the copies into the RPC client iovec.  -DaveM
- */
-int
-csum_partial_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
-{
-	skb_reader_t desc;
-
-	desc.skb = skb;
-	desc.offset = sizeof(struct udphdr);
-	desc.count = skb->len - desc.offset;
-
-	if (skb->ip_summed == CHECKSUM_UNNECESSARY)
-		goto no_checksum;
-
-	desc.csum = csum_partial(skb->data, desc.offset, skb->csum);
-	if (xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_and_csum_bits) < 0)
-		return -1;
-	if (desc.offset != skb->len) {
-		unsigned int csum2;
-		csum2 = skb_checksum(skb, desc.offset, skb->len - desc.offset, 0);
-		desc.csum = csum_block_add(desc.csum, csum2, desc.offset);
-	}
-	if (desc.count)
-		return -1;
-	if ((unsigned short)csum_fold(desc.csum))
-		return -1;
-	return 0;
-no_checksum:
-	if (xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_bits) < 0)
-		return -1;
-	if (desc.count)
-		return -1;
-	return 0;
-}
-
-/*
- * Input handler for RPC replies. Called from a bottom half and hence
- * atomic.
- */
-static void
-udp_data_ready(struct sock *sk, int len)
-{
-	struct rpc_task	*task;
-	struct rpc_xprt	*xprt;
-	struct rpc_rqst *rovr;
-	struct sk_buff	*skb;
-	int err, repsize, copied;
-	u32 _xid, *xp;
-
-	read_lock(&sk->sk_callback_lock);
-	dprintk("RPC:      udp_data_ready...\n");
-	if (!(xprt = xprt_from_sock(sk))) {
-		printk("RPC:      udp_data_ready request not found!\n");
-		goto out;
-	}
-
-	dprintk("RPC:      udp_data_ready client %p\n", xprt);
-
-	if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
-		goto out;
-
-	if (xprt->shutdown)
-		goto dropit;
-
-	repsize = skb->len - sizeof(struct udphdr);
-	if (repsize < 4) {
-		printk("RPC: impossible RPC reply size %d!\n", repsize);
-		goto dropit;
-	}
-
-	/* Copy the XID from the skb... */
-	xp = skb_header_pointer(skb, sizeof(struct udphdr),
-				sizeof(_xid), &_xid);
-	if (xp == NULL)
-		goto dropit;
-
-	/* Look up and lock the request corresponding to the given XID */
-	spin_lock(&xprt->sock_lock);
-	rovr = xprt_lookup_rqst(xprt, *xp);
-	if (!rovr)
-		goto out_unlock;
-	task = rovr->rq_task;
-
-	dprintk("RPC: %4d received reply\n", task->tk_pid);
-
-	if ((copied = rovr->rq_private_buf.buflen) > repsize)
-		copied = repsize;
-
-	/* Suck it into the iovec, verify checksum if not done by hw. */
-	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb))
-		goto out_unlock;
-
-	/* Something worked... */
-	dst_confirm(skb->dst);
-
-	xprt_complete_rqst(xprt, rovr, copied);
-
- out_unlock:
-	spin_unlock(&xprt->sock_lock);
- dropit:
-	skb_free_datagram(sk, skb);
- out:
-	read_unlock(&sk->sk_callback_lock);
-}
-
-/*
- * Copy from an skb into memory and shrink the skb.
- */
-static inline size_t
-tcp_copy_data(skb_reader_t *desc, void *p, size_t len)
-{
-	if (len > desc->count)
-		len = desc->count;
-	if (skb_copy_bits(desc->skb, desc->offset, p, len)) {
-		dprintk("RPC:      failed to copy %zu bytes from skb. %zu bytes remain\n",
-				len, desc->count);
-		return 0;
-	}
-	desc->offset += len;
-	desc->count -= len;
-	dprintk("RPC:      copied %zu bytes from skb. %zu bytes remain\n",
-			len, desc->count);
-	return len;
-}
-
-/*
- * TCP read fragment marker
- */
-static inline void
-tcp_read_fraghdr(struct rpc_xprt *xprt, skb_reader_t *desc)
-{
-	size_t len, used;
-	char *p;
-
-	p = ((char *) &xprt->tcp_recm) + xprt->tcp_offset;
-	len = sizeof(xprt->tcp_recm) - xprt->tcp_offset;
-	used = tcp_copy_data(desc, p, len);
-	xprt->tcp_offset += used;
-	if (used != len)
-		return;
-	xprt->tcp_reclen = ntohl(xprt->tcp_recm);
-	if (xprt->tcp_reclen & 0x80000000)
-		xprt->tcp_flags |= XPRT_LAST_FRAG;
-	else
-		xprt->tcp_flags &= ~XPRT_LAST_FRAG;
-	xprt->tcp_reclen &= 0x7fffffff;
-	xprt->tcp_flags &= ~XPRT_COPY_RECM;
-	xprt->tcp_offset = 0;
-	/* Sanity check of the record length */
-	if (xprt->tcp_reclen < 4) {
-		printk(KERN_ERR "RPC: Invalid TCP record fragment length\n");
-		xprt_disconnect(xprt);
-	}
-	dprintk("RPC:      reading TCP record fragment of length %d\n",
-			xprt->tcp_reclen);
-}
-
-static void
-tcp_check_recm(struct rpc_xprt *xprt)
-{
-	dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u, tcp_flags = %lx\n",
-			xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen, xprt->tcp_flags);
-	if (xprt->tcp_offset == xprt->tcp_reclen) {
-		xprt->tcp_flags |= XPRT_COPY_RECM;
-		xprt->tcp_offset = 0;
-		if (xprt->tcp_flags & XPRT_LAST_FRAG) {
-			xprt->tcp_flags &= ~XPRT_COPY_DATA;
-			xprt->tcp_flags |= XPRT_COPY_XID;
-			xprt->tcp_copied = 0;
-		}
-	}
-}
-
-/*
- * TCP read xid
- */
-static inline void
-tcp_read_xid(struct rpc_xprt *xprt, skb_reader_t *desc)
-{
-	size_t len, used;
-	char *p;
-
-	len = sizeof(xprt->tcp_xid) - xprt->tcp_offset;
-	dprintk("RPC:      reading XID (%Zu bytes)\n", len);
-	p = ((char *) &xprt->tcp_xid) + xprt->tcp_offset;
-	used = tcp_copy_data(desc, p, len);
-	xprt->tcp_offset += used;
-	if (used != len)
-		return;
-	xprt->tcp_flags &= ~XPRT_COPY_XID;
-	xprt->tcp_flags |= XPRT_COPY_DATA;
-	xprt->tcp_copied = 4;
-	dprintk("RPC:      reading reply for XID %08x\n",
-						ntohl(xprt->tcp_xid));
-	tcp_check_recm(xprt);
-}
-
-/*
- * TCP read and complete request
- */
-static inline void
-tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc)
-{
-	struct rpc_rqst *req;
-	struct xdr_buf *rcvbuf;
-	size_t len;
-	ssize_t r;
-
-	/* Find and lock the request corresponding to this xid */
-	spin_lock(&xprt->sock_lock);
-	req = xprt_lookup_rqst(xprt, xprt->tcp_xid);
-	if (!req) {
-		xprt->tcp_flags &= ~XPRT_COPY_DATA;
-		dprintk("RPC:      XID %08x request not found!\n",
-				ntohl(xprt->tcp_xid));
-		spin_unlock(&xprt->sock_lock);
-		return;
-	}
-
-	rcvbuf = &req->rq_private_buf;
-	len = desc->count;
-	if (len > xprt->tcp_reclen - xprt->tcp_offset) {
-		skb_reader_t my_desc;
-
-		len = xprt->tcp_reclen - xprt->tcp_offset;
-		memcpy(&my_desc, desc, sizeof(my_desc));
-		my_desc.count = len;
-		r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
-					  &my_desc, tcp_copy_data);
-		desc->count -= r;
-		desc->offset += r;
-	} else
-		r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
-					  desc, tcp_copy_data);
-
-	if (r > 0) {
-		xprt->tcp_copied += r;
-		xprt->tcp_offset += r;
-	}
-	if (r != len) {
-		/* Error when copying to the receive buffer,
-		 * usually because we weren't able to allocate
-		 * additional buffer pages. All we can do now
-		 * is turn off XPRT_COPY_DATA, so the request
-		 * will not receive any additional updates,
-		 * and time out.
-		 * Any remaining data from this record will
-		 * be discarded.
-		 */
-		xprt->tcp_flags &= ~XPRT_COPY_DATA;
-		dprintk("RPC:      XID %08x truncated request\n",
-				ntohl(xprt->tcp_xid));
-		dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
-				xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
-		goto out;
-	}
-
-	dprintk("RPC:      XID %08x read %Zd bytes\n",
-			ntohl(xprt->tcp_xid), r);
-	dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
-			xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
-
-	if (xprt->tcp_copied == req->rq_private_buf.buflen)
-		xprt->tcp_flags &= ~XPRT_COPY_DATA;
-	else if (xprt->tcp_offset == xprt->tcp_reclen) {
-		if (xprt->tcp_flags & XPRT_LAST_FRAG)
-			xprt->tcp_flags &= ~XPRT_COPY_DATA;
-	}
-
-out:
-	if (!(xprt->tcp_flags & XPRT_COPY_DATA)) {
-		dprintk("RPC: %4d received reply complete\n",
-				req->rq_task->tk_pid);
-		xprt_complete_rqst(xprt, req, xprt->tcp_copied);
-	}
-	spin_unlock(&xprt->sock_lock);
-	tcp_check_recm(xprt);
-}
-
-/*
- * TCP discard extra bytes from a short read
- */
-static inline void
-tcp_read_discard(struct rpc_xprt *xprt, skb_reader_t *desc)
-{
-	size_t len;
-
-	len = xprt->tcp_reclen - xprt->tcp_offset;
-	if (len > desc->count)
-		len = desc->count;
-	desc->count -= len;
-	desc->offset += len;
-	xprt->tcp_offset += len;
-	dprintk("RPC:      discarded %Zu bytes\n", len);
-	tcp_check_recm(xprt);
-}
-
-/*
- * TCP record receive routine
- * We first have to grab the record marker, then the XID, then the data.
+/**
+ * xprt_update_rtt - update an RPC client's RTT state after receiving a reply
+ * @task: RPC request that recently completed
+ *
  */
-static int
-tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
-		unsigned int offset, size_t len)
-{
-	struct rpc_xprt *xprt = rd_desc->arg.data;
-	skb_reader_t desc = {
-		.skb	= skb,
-		.offset	= offset,
-		.count	= len,
-		.csum	= 0
-       	};
-
-	dprintk("RPC:      tcp_data_recv\n");
-	do {
-		/* Read in a new fragment marker if necessary */
-		/* Can we ever really expect to get completely empty fragments? */
-		if (xprt->tcp_flags & XPRT_COPY_RECM) {
-			tcp_read_fraghdr(xprt, &desc);
-			continue;
-		}
-		/* Read in the xid if necessary */
-		if (xprt->tcp_flags & XPRT_COPY_XID) {
-			tcp_read_xid(xprt, &desc);
-			continue;
-		}
-		/* Read in the request data */
-		if (xprt->tcp_flags & XPRT_COPY_DATA) {
-			tcp_read_request(xprt, &desc);
-			continue;
-		}
-		/* Skip over any trailing bytes on short reads */
-		tcp_read_discard(xprt, &desc);
-	} while (desc.count);
-	dprintk("RPC:      tcp_data_recv done\n");
-	return len - desc.count;
-}
-
-static void tcp_data_ready(struct sock *sk, int bytes)
+void xprt_update_rtt(struct rpc_task *task)
 {
-	struct rpc_xprt *xprt;
-	read_descriptor_t rd_desc;
-
-	read_lock(&sk->sk_callback_lock);
-	dprintk("RPC:      tcp_data_ready...\n");
-	if (!(xprt = xprt_from_sock(sk))) {
-		printk("RPC:      tcp_data_ready socket info not found!\n");
-		goto out;
-	}
-	if (xprt->shutdown)
-		goto out;
-
-	/* We use rd_desc to pass struct xprt to tcp_data_recv */
-	rd_desc.arg.data = xprt;
-	rd_desc.count = 65536;
-	tcp_read_sock(sk, &rd_desc, tcp_data_recv);
-out:
-	read_unlock(&sk->sk_callback_lock);
-}
-
-static void
-tcp_state_change(struct sock *sk)
-{
-	struct rpc_xprt	*xprt;
+	struct rpc_rqst *req = task->tk_rqstp;
+	struct rpc_rtt *rtt = task->tk_client->cl_rtt;
+	unsigned timer = task->tk_msg.rpc_proc->p_timer;
 
-	read_lock(&sk->sk_callback_lock);
-	if (!(xprt = xprt_from_sock(sk)))
-		goto out;
-	dprintk("RPC:      tcp_state_change client %p...\n", xprt);
-	dprintk("RPC:      state %x conn %d dead %d zapped %d\n",
-				sk->sk_state, xprt_connected(xprt),
-				sock_flag(sk, SOCK_DEAD),
-				sock_flag(sk, SOCK_ZAPPED));
-
-	switch (sk->sk_state) {
-	case TCP_ESTABLISHED:
-		spin_lock_bh(&xprt->sock_lock);
-		if (!xprt_test_and_set_connected(xprt)) {
-			/* Reset TCP record info */
-			xprt->tcp_offset = 0;
-			xprt->tcp_reclen = 0;
-			xprt->tcp_copied = 0;
-			xprt->tcp_flags = XPRT_COPY_RECM | XPRT_COPY_XID;
-			rpc_wake_up(&xprt->pending);
-		}
-		spin_unlock_bh(&xprt->sock_lock);
-		break;
-	case TCP_SYN_SENT:
-	case TCP_SYN_RECV:
-		break;
-	default:
-		xprt_disconnect(xprt);
-		break;
+	if (timer) {
+		if (req->rq_ntrans == 1)
+			rpc_update_rtt(rtt, timer,
+					(long)jiffies - req->rq_xtime);
+		rpc_set_timeo(rtt, timer, req->rq_ntrans - 1);
 	}
- out:
-	read_unlock(&sk->sk_callback_lock);
 }
 
-/*
- * Called when more output buffer space is available for this socket.
- * We try not to wake our writers until they can make "significant"
- * progress, otherwise we'll waste resources thrashing sock_sendmsg
- * with a bunch of small requests.
+/**
+ * xprt_complete_rqst - called when reply processing is complete
+ * @task: RPC request that recently completed
+ * @copied: actual number of bytes received from the transport
+ *
+ * Caller holds transport lock.
  */
-static void
-xprt_write_space(struct sock *sk)
+void xprt_complete_rqst(struct rpc_task *task, int copied)
 {
-	struct rpc_xprt	*xprt;
-	struct socket	*sock;
-
-	read_lock(&sk->sk_callback_lock);
-	if (!(xprt = xprt_from_sock(sk)) || !(sock = sk->sk_socket))
-		goto out;
-	if (xprt->shutdown)
-		goto out;
-
-	/* Wait until we have enough socket memory */
-	if (xprt->stream) {
-		/* from net/core/stream.c:sk_stream_write_space */
-		if (sk_stream_wspace(sk) < sk_stream_min_wspace(sk))
-			goto out;
-	} else {
-		/* from net/core/sock.c:sock_def_write_space */
-		if (!sock_writeable(sk))
-			goto out;
-	}
+	struct rpc_rqst *req = task->tk_rqstp;
 
-	if (!test_and_clear_bit(SOCK_NOSPACE, &sock->flags))
-		goto out;
+	dprintk("RPC: %5u xid %08x complete (%d bytes received)\n",
+			task->tk_pid, ntohl(req->rq_xid), copied);
 
-	spin_lock_bh(&xprt->sock_lock);
-	if (xprt->snd_task)
-		rpc_wake_up_task(xprt->snd_task);
-	spin_unlock_bh(&xprt->sock_lock);
-out:
-	read_unlock(&sk->sk_callback_lock);
+	list_del_init(&req->rq_list);
+	req->rq_received = req->rq_private_buf.len = copied;
+	rpc_wake_up_task(task);
 }
 
-/*
- * RPC receive timeout handler.
- */
-static void
-xprt_timer(struct rpc_task *task)
+static void xprt_timer(struct rpc_task *task)
 {
-	struct rpc_rqst	*req = task->tk_rqstp;
+	struct rpc_rqst *req = task->tk_rqstp;
 	struct rpc_xprt *xprt = req->rq_xprt;
 
-	spin_lock(&xprt->sock_lock);
-	if (req->rq_received)
-		goto out;
-
-	xprt_adjust_cwnd(req->rq_xprt, -ETIMEDOUT);
-	__xprt_put_cong(xprt, req);
+	dprintk("RPC: %4d xprt_timer\n", task->tk_pid);
 
-	dprintk("RPC: %4d xprt_timer (%s request)\n",
-		task->tk_pid, req ? "pending" : "backlogged");
-
-	task->tk_status  = -ETIMEDOUT;
-out:
+	spin_lock(&xprt->transport_lock);
+	if (!req->rq_received) {
+		if (xprt->ops->timer)
+			xprt->ops->timer(task);
+		task->tk_status = -ETIMEDOUT;
+	}
 	task->tk_timeout = 0;
 	rpc_wake_up_task(task);
-	spin_unlock(&xprt->sock_lock);
+	spin_unlock(&xprt->transport_lock);
 }
 
-/*
- * Place the actual RPC call.
- * We have to copy the iovec because sendmsg fiddles with its contents.
+/**
+ * xprt_prepare_transmit - reserve the transport before sending a request
+ * @task: RPC task about to send a request
+ *
  */
-int
-xprt_prepare_transmit(struct rpc_task *task)
+int xprt_prepare_transmit(struct rpc_task *task)
 {
 	struct rpc_rqst	*req = task->tk_rqstp;
 	struct rpc_xprt	*xprt = req->rq_xprt;
@@ -1191,12 +690,12 @@ xprt_prepare_transmit(struct rpc_task *task)
 	if (xprt->shutdown)
 		return -EIO;
 
-	spin_lock_bh(&xprt->sock_lock);
+	spin_lock_bh(&xprt->transport_lock);
 	if (req->rq_received && !req->rq_bytes_sent) {
 		err = req->rq_received;
 		goto out_unlock;
 	}
-	if (!__xprt_lock_write(xprt, task)) {
+	if (!xprt->ops->reserve_xprt(task)) {
 		err = -EAGAIN;
 		goto out_unlock;
 	}
@@ -1206,39 +705,42 @@ xprt_prepare_transmit(struct rpc_task *task)
 		goto out_unlock;
 	}
 out_unlock:
-	spin_unlock_bh(&xprt->sock_lock);
+	spin_unlock_bh(&xprt->transport_lock);
 	return err;
 }
 
 void
-xprt_transmit(struct rpc_task *task)
+xprt_abort_transmit(struct rpc_task *task)
+{
+	struct rpc_xprt	*xprt = task->tk_xprt;
+
+	xprt_release_write(xprt, task);
+}
+
+/**
+ * xprt_transmit - send an RPC request on a transport
+ * @task: controlling RPC task
+ *
+ * We have to copy the iovec because sendmsg fiddles with its contents.
+ */
+void xprt_transmit(struct rpc_task *task)
 {
-	struct rpc_clnt *clnt = task->tk_client;
 	struct rpc_rqst	*req = task->tk_rqstp;
 	struct rpc_xprt	*xprt = req->rq_xprt;
-	int status, retry = 0;
-
+	int status;
 
 	dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
 
-	/* set up everything as needed. */
-	/* Write the record marker */
-	if (xprt->stream) {
-		u32	*marker = req->rq_svec[0].iov_base;
-
-		*marker = htonl(0x80000000|(req->rq_slen-sizeof(*marker)));
-	}
-
 	smp_rmb();
 	if (!req->rq_received) {
 		if (list_empty(&req->rq_list)) {
-			spin_lock_bh(&xprt->sock_lock);
+			spin_lock_bh(&xprt->transport_lock);
 			/* Update the softirq receive buffer */
 			memcpy(&req->rq_private_buf, &req->rq_rcv_buf,
 					sizeof(req->rq_private_buf));
 			/* Add request to the receive list */
 			list_add_tail(&req->rq_list, &xprt->recv);
-			spin_unlock_bh(&xprt->sock_lock);
+			spin_unlock_bh(&xprt->transport_lock);
 			xprt_reset_majortimeo(req);
 			/* Turn off autodisconnect */
 			del_singleshot_timer_sync(&xprt->timer);
@@ -1246,40 +748,19 @@ xprt_transmit(struct rpc_task *task)
 	} else if (!req->rq_bytes_sent)
 		return;
 
-	/* Continue transmitting the packet/record. We must be careful
-	 * to cope with writespace callbacks arriving _after_ we have
-	 * called xprt_sendmsg().
-	 */
-	while (1) {
-		req->rq_xtime = jiffies;
-		status = xprt_sendmsg(xprt, req);
-
-		if (status < 0)
-			break;
-
-		if (xprt->stream) {
-			req->rq_bytes_sent += status;
-
-			/* If we've sent the entire packet, immediately
-			 * reset the count of bytes sent. */
-			if (req->rq_bytes_sent >= req->rq_slen) {
-				req->rq_bytes_sent = 0;
-				goto out_receive;
-			}
-		} else {
-			if (status >= req->rq_slen)
-				goto out_receive;
-			status = -EAGAIN;
-			break;
-		}
-
-		dprintk("RPC: %4d xmit incomplete (%d left of %d)\n",
-				task->tk_pid, req->rq_slen - req->rq_bytes_sent,
-				req->rq_slen);
-
-		status = -EAGAIN;
-		if (retry++ > 50)
-			break;
+	status = xprt->ops->send_request(task);
+	if (status == 0) {
+		dprintk("RPC: %4d xmit complete\n", task->tk_pid);
+		spin_lock_bh(&xprt->transport_lock);
+		xprt->ops->set_retrans_timeout(task);
+		/* Don't race with disconnect */
+		if (!xprt_connected(xprt))
+			task->tk_status = -ENOTCONN;
+		else if (!req->rq_received)
+			rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer);
+		xprt->ops->release_xprt(xprt, task);
+		spin_unlock_bh(&xprt->transport_lock);
+		return;
 	}
 
 	/* Note: at this point, task->tk_sleeping has not yet been set,
@@ -1289,60 +770,19 @@ xprt_transmit(struct rpc_task *task)
 	task->tk_status = status;
 
 	switch (status) {
-	case -EAGAIN:
-		if (test_bit(SOCK_ASYNC_NOSPACE, &xprt->sock->flags)) {
-			/* Protect against races with xprt_write_space */
-			spin_lock_bh(&xprt->sock_lock);
-			/* Don't race with disconnect */
-			if (!xprt_connected(xprt))
-				task->tk_status = -ENOTCONN;
-			else if (test_bit(SOCK_NOSPACE, &xprt->sock->flags)) {
-				task->tk_timeout = req->rq_timeout;
-				rpc_sleep_on(&xprt->pending, task, NULL, NULL);
-			}
-			spin_unlock_bh(&xprt->sock_lock);
-			return;
-		}
-		/* Keep holding the socket if it is blocked */
-		rpc_delay(task, HZ>>4);
-		return;
 	case -ECONNREFUSED:
-		task->tk_timeout = RPC_REESTABLISH_TIMEOUT;
 		rpc_sleep_on(&xprt->sending, task, NULL, NULL);
+	case -EAGAIN:
 	case -ENOTCONN:
 		return;
 	default:
-		if (xprt->stream)
-			xprt_disconnect(xprt);
+		break;
 	}
 	xprt_release_write(xprt, task);
 	return;
- out_receive:
-	dprintk("RPC: %4d xmit complete\n", task->tk_pid);
-	/* Set the task's receive timeout value */
-	spin_lock_bh(&xprt->sock_lock);
-	if (!xprt->nocong) {
-		int timer = task->tk_msg.rpc_proc->p_timer;
-		task->tk_timeout = rpc_calc_rto(clnt->cl_rtt, timer);
-		task->tk_timeout <<= rpc_ntimeo(clnt->cl_rtt, timer) + req->rq_retries;
-		if (task->tk_timeout > xprt->timeout.to_maxval || task->tk_timeout == 0)
-			task->tk_timeout = xprt->timeout.to_maxval;
-	} else
-		task->tk_timeout = req->rq_timeout;
-	/* Don't race with disconnect */
-	if (!xprt_connected(xprt))
-		task->tk_status = -ENOTCONN;
-	else if (!req->rq_received)
-		rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer);
-	__xprt_release_write(xprt, task);
-	spin_unlock_bh(&xprt->sock_lock);
 }
 
-/*
- * Reserve an RPC call slot.
- */
-static inline void
-do_xprt_reserve(struct rpc_task *task)
+static inline void do_xprt_reserve(struct rpc_task *task)
 {
 	struct rpc_xprt	*xprt = task->tk_xprt;
 
@@ -1362,22 +802,25 @@ do_xprt_reserve(struct rpc_task *task)
 	rpc_sleep_on(&xprt->backlog, task, NULL, NULL);
 }
 
-void
-xprt_reserve(struct rpc_task *task)
+/**
+ * xprt_reserve - allocate an RPC request slot
+ * @task: RPC task requesting a slot allocation
+ *
+ * If no more slots are available, place the task on the transport's
+ * backlog queue.
+ */
+void xprt_reserve(struct rpc_task *task)
 {
 	struct rpc_xprt	*xprt = task->tk_xprt;
 
 	task->tk_status = -EIO;
 	if (!xprt->shutdown) {
-		spin_lock(&xprt->xprt_lock);
+		spin_lock(&xprt->reserve_lock);
 		do_xprt_reserve(task);
-		spin_unlock(&xprt->xprt_lock);
+		spin_unlock(&xprt->reserve_lock);
 	}
 }
 
-/*
- * Allocate a 'unique' XID
- */
 static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt)
 {
 	return xprt->xid++;
@@ -1388,11 +831,7 @@ static inline void xprt_init_xid(struct rpc_xprt *xprt)
 	get_random_bytes(&xprt->xid, sizeof(xprt->xid));
 }
 
-/*
- * Initialize RPC request
- */
-static void
-xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
+static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
 {
 	struct rpc_rqst	*req = task->tk_rqstp;
 
@@ -1400,128 +839,104 @@ xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
 	req->rq_task	= task;
 	req->rq_xprt    = xprt;
 	req->rq_xid     = xprt_alloc_xid(xprt);
+	req->rq_release_snd_buf = NULL;
 	dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid,
 			req, ntohl(req->rq_xid));
 }
 
-/*
- * Release an RPC call slot
+/**
+ * xprt_release - release an RPC request slot
+ * @task: task which is finished with the slot
+ *
  */
-void
-xprt_release(struct rpc_task *task)
+void xprt_release(struct rpc_task *task)
 {
 	struct rpc_xprt	*xprt = task->tk_xprt;
 	struct rpc_rqst	*req;
 
 	if (!(req = task->tk_rqstp))
 		return;
-	spin_lock_bh(&xprt->sock_lock);
-	__xprt_release_write(xprt, task);
-	__xprt_put_cong(xprt, req);
+	spin_lock_bh(&xprt->transport_lock);
+	xprt->ops->release_xprt(xprt, task);
+	if (xprt->ops->release_request)
+		xprt->ops->release_request(task);
 	if (!list_empty(&req->rq_list))
 		list_del(&req->rq_list);
 	xprt->last_used = jiffies;
 	if (list_empty(&xprt->recv) && !xprt->shutdown)
-		mod_timer(&xprt->timer, xprt->last_used + XPRT_IDLE_TIMEOUT);
-	spin_unlock_bh(&xprt->sock_lock);
+		mod_timer(&xprt->timer,
+				xprt->last_used + xprt->idle_timeout);
+	spin_unlock_bh(&xprt->transport_lock);
 	task->tk_rqstp = NULL;
+	if (req->rq_release_snd_buf)
+		req->rq_release_snd_buf(req);
 	memset(req, 0, sizeof(*req));	/* mark unused */
 
 	dprintk("RPC: %4d release request %p\n", task->tk_pid, req);
 
-	spin_lock(&xprt->xprt_lock);
+	spin_lock(&xprt->reserve_lock);
 	list_add(&req->rq_list, &xprt->free);
-	xprt_clear_backlog(xprt);
-	spin_unlock(&xprt->xprt_lock);
-}
-
-/*
- * Set default timeout parameters
- */
-static void
-xprt_default_timeout(struct rpc_timeout *to, int proto)
-{
-	if (proto == IPPROTO_UDP)
-		xprt_set_timeout(to, 5,  5 * HZ);
-	else
-		xprt_set_timeout(to, 5, 60 * HZ);
+	rpc_wake_up_next(&xprt->backlog);
+	spin_unlock(&xprt->reserve_lock);
 }
 
-/*
- * Set constant timeout
+/**
+ * xprt_set_timeout - set constant RPC timeout
+ * @to: RPC timeout parameters to set up
+ * @retr: number of retries
+ * @incr: amount of increase after each retry
+ *
  */
-void
-xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr)
+void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr)
 {
 	to->to_initval   = 
 	to->to_increment = incr;
-	to->to_maxval    = incr * retr;
+	to->to_maxval    = to->to_initval + (incr * retr);
 	to->to_retries   = retr;
 	to->to_exponential = 0;
 }
 
-unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
-unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
-
-/*
- * Initialize an RPC client
- */
-static struct rpc_xprt *
-xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to)
+static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to)
 {
+	int result;
 	struct rpc_xprt	*xprt;
-	unsigned int entries;
-	size_t slot_table_size;
 	struct rpc_rqst	*req;
 
-	dprintk("RPC:      setting up %s transport...\n",
-				proto == IPPROTO_UDP? "UDP" : "TCP");
-
-	entries = (proto == IPPROTO_TCP)?
-		xprt_tcp_slot_table_entries : xprt_udp_slot_table_entries;
-
 	if ((xprt = kmalloc(sizeof(struct rpc_xprt), GFP_KERNEL)) == NULL)
 		return ERR_PTR(-ENOMEM);
 	memset(xprt, 0, sizeof(*xprt)); /* Nnnngh! */
-	xprt->max_reqs = entries;
-	slot_table_size = entries * sizeof(xprt->slot[0]);
-	xprt->slot = kmalloc(slot_table_size, GFP_KERNEL);
-	if (xprt->slot == NULL) {
-		kfree(xprt);
-		return ERR_PTR(-ENOMEM);
-	}
-	memset(xprt->slot, 0, slot_table_size);
 
 	xprt->addr = *ap;
-	xprt->prot = proto;
-	xprt->stream = (proto == IPPROTO_TCP)? 1 : 0;
-	if (xprt->stream) {
-		xprt->cwnd = RPC_MAXCWND(xprt);
-		xprt->nocong = 1;
-		xprt->max_payload = (1U << 31) - 1;
-	} else {
-		xprt->cwnd = RPC_INITCWND;
-		xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
+
+	switch (proto) {
+	case IPPROTO_UDP:
+		result = xs_setup_udp(xprt, to);
+		break;
+	case IPPROTO_TCP:
+		result = xs_setup_tcp(xprt, to);
+		break;
+	default:
+		printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n",
+				proto);
+		result = -EIO;
+		break;
+	}
+	if (result) {
+		kfree(xprt);
+		return ERR_PTR(result);
 	}
-	spin_lock_init(&xprt->sock_lock);
-	spin_lock_init(&xprt->xprt_lock);
-	init_waitqueue_head(&xprt->cong_wait);
+
+	spin_lock_init(&xprt->transport_lock);
+	spin_lock_init(&xprt->reserve_lock);
 
 	INIT_LIST_HEAD(&xprt->free);
 	INIT_LIST_HEAD(&xprt->recv);
-	INIT_WORK(&xprt->sock_connect, xprt_socket_connect, xprt);
-	INIT_WORK(&xprt->task_cleanup, xprt_socket_autoclose, xprt);
+	INIT_WORK(&xprt->task_cleanup, xprt_autoclose, xprt);
 	init_timer(&xprt->timer);
 	xprt->timer.function = xprt_init_autodisconnect;
 	xprt->timer.data = (unsigned long) xprt;
 	xprt->last_used = jiffies;
-	xprt->port = XPRT_MAX_RESVPORT;
-
-	/* Set timeout parameters */
-	if (to) {
-		xprt->timeout = *to;
-	} else
-		xprt_default_timeout(&xprt->timeout, xprt->prot);
+	xprt->cwnd = RPC_INITCWND;
 
 	rpc_init_wait_queue(&xprt->pending, "xprt_pending");
 	rpc_init_wait_queue(&xprt->sending, "xprt_sending");
@@ -1529,139 +944,25 @@ xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to)
 	rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog");
 
 	/* initialize free list */
-	for (req = &xprt->slot[entries-1]; req >= &xprt->slot[0]; req--)
+	for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--)
 		list_add(&req->rq_list, &xprt->free);
 
 	xprt_init_xid(xprt);
 
-	/* Check whether we want to use a reserved port */
-	xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0;
-
 	dprintk("RPC:      created transport %p with %u slots\n", xprt,
 			xprt->max_reqs);
 	
 	return xprt;
 }
 
-/*
- * Bind to a reserved port
- */
-static inline int xprt_bindresvport(struct rpc_xprt *xprt, struct socket *sock)
-{
-	struct sockaddr_in myaddr = {
-		.sin_family = AF_INET,
-	};
-	int		err, port;
-
-	/* Were we already bound to a given port? Try to reuse it */
-	port = xprt->port;
-	do {
-		myaddr.sin_port = htons(port);
-		err = sock->ops->bind(sock, (struct sockaddr *) &myaddr,
-						sizeof(myaddr));
-		if (err == 0) {
-			xprt->port = port;
-			return 0;
-		}
-		if (--port == 0)
-			port = XPRT_MAX_RESVPORT;
-	} while (err == -EADDRINUSE && port != xprt->port);
-
-	printk("RPC: Can't bind to reserved port (%d).\n", -err);
-	return err;
-}
-
-static void
-xprt_bind_socket(struct rpc_xprt *xprt, struct socket *sock)
-{
-	struct sock	*sk = sock->sk;
-
-	if (xprt->inet)
-		return;
-
-	write_lock_bh(&sk->sk_callback_lock);
-	sk->sk_user_data = xprt;
-	xprt->old_data_ready = sk->sk_data_ready;
-	xprt->old_state_change = sk->sk_state_change;
-	xprt->old_write_space = sk->sk_write_space;
-	if (xprt->prot == IPPROTO_UDP) {
-		sk->sk_data_ready = udp_data_ready;
-		sk->sk_no_check = UDP_CSUM_NORCV;
-		xprt_set_connected(xprt);
-	} else {
-		tcp_sk(sk)->nonagle = 1;	/* disable Nagle's algorithm */
-		sk->sk_data_ready = tcp_data_ready;
-		sk->sk_state_change = tcp_state_change;
-		xprt_clear_connected(xprt);
-	}
-	sk->sk_write_space = xprt_write_space;
-
-	/* Reset to new socket */
-	xprt->sock = sock;
-	xprt->inet = sk;
-	write_unlock_bh(&sk->sk_callback_lock);
-
-	return;
-}
-
-/*
- * Set socket buffer length
- */
-void
-xprt_sock_setbufsize(struct rpc_xprt *xprt)
-{
-	struct sock *sk = xprt->inet;
-
-	if (xprt->stream)
-		return;
-	if (xprt->rcvsize) {
-		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
-		sk->sk_rcvbuf = xprt->rcvsize * xprt->max_reqs *  2;
-	}
-	if (xprt->sndsize) {
-		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
-		sk->sk_sndbuf = xprt->sndsize * xprt->max_reqs * 2;
-		sk->sk_write_space(sk);
-	}
-}
-
-/*
- * Datastream sockets are created here, but xprt_connect will create
- * and connect stream sockets.
- */
-static struct socket * xprt_create_socket(struct rpc_xprt *xprt, int proto, int resvport)
-{
-	struct socket	*sock;
-	int		type, err;
-
-	dprintk("RPC:      xprt_create_socket(%s %d)\n",
-			   (proto == IPPROTO_UDP)? "udp" : "tcp", proto);
-
-	type = (proto == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
-
-	if ((err = sock_create_kern(PF_INET, type, proto, &sock)) < 0) {
-		printk("RPC: can't create socket (%d).\n", -err);
-		return NULL;
-	}
-
-	/* If the caller has the capability, bind to a reserved port */
-	if (resvport && xprt_bindresvport(xprt, sock) < 0) {
-		printk("RPC: can't bind to reserved port.\n");
-		goto failed;
-	}
-
-	return sock;
-
-failed:
-	sock_release(sock);
-	return NULL;
-}
-
-/*
- * Create an RPC client transport given the protocol and peer address.
+/**
+ * xprt_create_proto - create an RPC client transport
+ * @proto: requested transport protocol
+ * @sap: remote peer's address
+ * @to: timeout parameters for new transport
+ *
  */
-struct rpc_xprt *
-xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to)
+struct rpc_xprt *xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to)
 {
 	struct rpc_xprt	*xprt;
 
@@ -1673,46 +974,26 @@ xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to)
 	return xprt;
 }
 
-/*
- * Prepare for transport shutdown.
- */
-static void
-xprt_shutdown(struct rpc_xprt *xprt)
+static void xprt_shutdown(struct rpc_xprt *xprt)
 {
 	xprt->shutdown = 1;
 	rpc_wake_up(&xprt->sending);
 	rpc_wake_up(&xprt->resend);
-	rpc_wake_up(&xprt->pending);
+	xprt_wake_pending_tasks(xprt, -EIO);
 	rpc_wake_up(&xprt->backlog);
-	wake_up(&xprt->cong_wait);
 	del_timer_sync(&xprt->timer);
-
-	/* synchronously wait for connect worker to finish */
-	cancel_delayed_work(&xprt->sock_connect);
-	flush_scheduled_work();
 }
 
-/*
- * Clear the xprt backlog queue
- */
-static int
-xprt_clear_backlog(struct rpc_xprt *xprt) {
-	rpc_wake_up_next(&xprt->backlog);
-	wake_up(&xprt->cong_wait);
-	return 1;
-}
-
-/*
- * Destroy an RPC transport, killing off all requests.
+/**
+ * xprt_destroy - destroy an RPC transport, killing off all requests.
+ * @xprt: transport to destroy
+ *
  */
-int
-xprt_destroy(struct rpc_xprt *xprt)
+int xprt_destroy(struct rpc_xprt *xprt)
 {
 	dprintk("RPC:      destroying transport %p\n", xprt);
 	xprt_shutdown(xprt);
-	xprt_disconnect(xprt);
-	xprt_close(xprt);
-	kfree(xprt->slot);
+	xprt->ops->destroy(xprt);
 	kfree(xprt);
 
 	return 0;