Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1678 insertions, 0 deletions

diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
new file mode 100644
index 000000000000..c74a6bb94074
--- /dev/null
+++ b/net/sunrpc/xprt.c
@@ -0,0 +1,1678 @@
+/*
+ *  linux/net/sunrpc/xprt.c
+ *
+ *  This is a generic RPC call interface supporting congestion avoidance,
+ *  and asynchronous calls.
+ *
+ *  The interface works like this:
+ *
+ *  -	When a process places a call, it allocates a request slot if
+ *	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
+ *	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
+ *	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
+ *	timeout values (minor timeout) or wakes up the caller with a status
+ *	of -ETIMEDOUT.
+ *  -	When the caller receives a notification from RPC that a reply arrived,
+ *	it should release the RPC slot, and process the reply.
+ *	If the call timed out, it may choose to retry the operation by
+ *	adjusting the initial timeout value, and simply calling rpc_call
+ *	again.
+ *
+ *  Support for async RPC is done through a set of RPC-specific scheduling
+ *  primitives that `transparently' work for processes as well as async
+ *  tasks that rely on callbacks.
+ *
+ *  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>
+ */
+
+#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/workqueue.h>
+#include <linux/random.h>
+
+#include <net/sock.h>
+#include <net/checksum.h>
+#include <net/udp.h>
+#include <net/tcp.h>
+
+/*
+ * Local variables
+ */
+
+#ifdef RPC_DEBUG
+# undef  RPC_DEBUG_DATA
+# 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).
+ */
+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
+
+/*
+ * Look up RPC transport given an INET socket
+ */
+static inline struct rpc_xprt *
+xprt_from_sock(struct sock *sk)
+{
+	return (struct rpc_xprt *) sk->sk_user_data;
+}
+
+/*
+ * 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.
+ */
+static int
+__xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+	struct rpc_rqst *req = task->tk_rqstp;
+
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) {
+		if (task == xprt->snd_task)
+			return 1;
+		if (task == NULL)
+			return 0;
+		goto out_sleep;
+	}
+	if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+		xprt->snd_task = task;
+		if (req) {
+			req->rq_bytes_sent = 0;
+			req->rq_ntrans++;
+		}
+		return 1;
+	}
+	smp_mb__before_clear_bit();
+	clear_bit(XPRT_LOCKED, &xprt->sockstate);
+	smp_mb__after_clear_bit();
+out_sleep:
+	dprintk("RPC: %4d failed to lock socket %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;
+}
+
+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);
+	return retval;
+}
+
+
+static void
+__xprt_lock_write_next(struct rpc_xprt *xprt)
+{
+	struct rpc_task *task;
+
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
+		return;
+	if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
+		goto out_unlock;
+	task = rpc_wake_up_next(&xprt->resend);
+	if (!task) {
+		task = rpc_wake_up_next(&xprt->sending);
+		if (!task)
+			goto out_unlock;
+	}
+	if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+		struct rpc_rqst *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->sockstate);
+	smp_mb__after_clear_bit();
+}
+
+/*
+ * Releases the socket for use by other requests.
+ */
+static void
+__xprt_release_write(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);
+		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.
+ */
+static inline int
+xprt_sendmsg(struct rpc_xprt *xprt, struct rpc_rqst *req)
+{
+	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);
+	}
+	/* 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;
+}
+
+/*
+ * Van Jacobson congestion avoidance. Check if the congestion window
+ * overflowed. Put the task to sleep if this is the case.
+ */
+static int
+__xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+	struct rpc_rqst *req = task->tk_rqstp;
+
+	if (req->rq_cong)
+		return 1;
+	dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n",
+			task->tk_pid, xprt->cong, xprt->cwnd);
+	if (RPCXPRT_CONGESTED(xprt))
+		return 0;
+	req->rq_cong = 1;
+	xprt->cong += RPC_CWNDSCALE;
+	return 1;
+}
+
+/*
+ * Adjust the congestion window, and wake up the next task
+ * that has been sleeping due to congestion
+ */
+static void
+__xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req)
+{
+	if (!req->rq_cong)
+		return;
+	req->rq_cong = 0;
+	xprt->cong -= RPC_CWNDSCALE;
+	__xprt_lock_write_next(xprt);
+}
+
+/*
+ * Adjust RPC congestion window
+ * We use a time-smoothed congestion estimator to avoid heavy oscillation.
+ */
+static void
+xprt_adjust_cwnd(struct rpc_xprt *xprt, int result)
+{
+	unsigned long	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);
+	} else if (result == -ETIMEDOUT) {
+		cwnd >>= 1;
+		if (cwnd < RPC_CWNDSCALE)
+			cwnd = RPC_CWNDSCALE;
+	}
+	dprintk("RPC:      cong %ld, cwnd was %ld, now %ld\n",
+			xprt->cong, xprt->cwnd, cwnd);
+	xprt->cwnd = cwnd;
+}
+
+/*
+ * Reset the major timeout value
+ */
+static void xprt_reset_majortimeo(struct rpc_rqst *req)
+{
+	struct rpc_timeout *to = &req->rq_xprt->timeout;
+
+	req->rq_majortimeo = req->rq_timeout;
+	if (to->to_exponential)
+		req->rq_majortimeo <<= to->to_retries;
+	else
+		req->rq_majortimeo += to->to_increment * to->to_retries;
+	if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0)
+		req->rq_majortimeo = to->to_maxval;
+	req->rq_majortimeo += jiffies;
+}
+
+/*
+ * Adjust timeout values etc for next retransmit
+ */
+int xprt_adjust_timeout(struct rpc_rqst *req)
+{
+	struct rpc_xprt *xprt = req->rq_xprt;
+	struct rpc_timeout *to = &xprt->timeout;
+	int status = 0;
+
+	if (time_before(jiffies, req->rq_majortimeo)) {
+		if (to->to_exponential)
+			req->rq_timeout <<= 1;
+		else
+			req->rq_timeout += to->to_increment;
+		if (to->to_maxval && req->rq_timeout >= to->to_maxval)
+			req->rq_timeout = to->to_maxval;
+		req->rq_retries++;
+		pprintk("RPC: %lu retrans\n", jiffies);
+	} else {
+		req->rq_timeout = to->to_initval;
+		req->rq_retries = 0;
+		xprt_reset_majortimeo(req);
+		/* Reset the RTT counters == "slow start" */
+		spin_lock_bh(&xprt->sock_lock);
+		rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
+		spin_unlock_bh(&xprt->sock_lock);
+		pprintk("RPC: %lu timeout\n", jiffies);
+		status = -ETIMEDOUT;
+	}
+
+	if (req->rq_timeout == 0) {
+		printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n");
+		req->rq_timeout = 5 * HZ;
+	}
+	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)
+{
+	struct rpc_xprt *xprt = (struct rpc_xprt *)args;
+
+	xprt_disconnect(xprt);
+	xprt_close(xprt);
+	xprt_release_write(xprt, NULL);
+}
+
+/*
+ * Mark a transport as disconnected
+ */
+static void
+xprt_disconnect(struct rpc_xprt *xprt)
+{
+	dprintk("RPC:      disconnected transport %p\n", xprt);
+	spin_lock_bh(&xprt->sock_lock);
+	xprt_clear_connected(xprt);
+	rpc_wake_up_status(&xprt->pending, -ENOTCONN);
+	spin_unlock_bh(&xprt->sock_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);
+	if (!list_empty(&xprt->recv) || xprt->shutdown)
+		goto out_abort;
+	if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
+		goto out_abort;
+	spin_unlock(&xprt->sock_lock);
+	/* Let keventd close the socket */
+	if (test_bit(XPRT_CONNECTING, &xprt->sockstate) != 0)
+		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();
+}
+
+/*
+ * Attempt to connect a TCP socket.
+ *
+ */
+void xprt_connect(struct rpc_task *task)
+{
+	struct rpc_xprt	*xprt = task->tk_xprt;
+
+	dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task->tk_pid,
+			xprt, (xprt_connected(xprt) ? "is" : "is not"));
+
+	if (xprt->shutdown) {
+		task->tk_status = -EIO;
+		return;
+	}
+	if (!xprt->addr.sin_port) {
+		task->tk_status = -EIO;
+		return;
+	}
+	if (!xprt_lock_write(xprt, task))
+		return;
+	if (xprt_connected(xprt))
+		goto out_write;
+
+	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);
+	}
+	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)
+{
+	struct rpc_xprt	*xprt = task->tk_xprt;
+
+	if (task->tk_status >= 0) {
+		dprintk("RPC: %4d xprt_connect_status: connection established\n",
+				task->tk_pid);
+		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:
+	case -ENOTCONN:
+		return;
+	case -ETIMEDOUT:
+		dprintk("RPC: %4d xprt_connect_status: 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);
+	}
+	xprt_release_write(xprt, task);
+}
+
+/*
+ * Look up the RPC request corresponding to a reply, and then lock it.
+ */
+static inline struct rpc_rqst *
+xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
+{
+	struct list_head *pos;
+	struct rpc_rqst	*req = NULL;
+
+	list_for_each(pos, &xprt->recv) {
+		struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list);
+		if (entry->rq_xid == xid) {
+			req = entry;
+			break;
+		}
+	}
+	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);
+	xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_and_csum_bits);
+	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:
+	xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_bits);
+	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))
+		return 0;
+	desc->offset += len;
+	desc->count -= len;
+	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)
+{
+	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;
+
+	/* 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;
+		xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
+					  &my_desc, tcp_copy_data);
+		desc->count -= len;
+		desc->offset += len;
+	} else
+		xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
+					  desc, tcp_copy_data);
+	xprt->tcp_copied += len;
+	xprt->tcp_offset += len;
+
+	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;
+	}
+
+	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;
+	tcp_check_recm(xprt);
+}
+
+/*
+ * TCP record receive routine
+ * We first have to grab the record marker, then the XID, then the data.
+ */
+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)
+{
+	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;
+
+	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:
+		if (xprt_test_and_clear_connected(xprt))
+			rpc_wake_up_status(&xprt->pending, -ENOTCONN);
+		break;
+	}
+ 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.
+ */
+static void
+xprt_write_space(struct sock *sk)
+{
+	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;
+	}
+
+	if (!test_and_clear_bit(SOCK_NOSPACE, &sock->flags))
+		goto out;
+
+	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);
+}
+
+/*
+ * RPC receive timeout handler.
+ */
+static void
+xprt_timer(struct rpc_task *task)
+{
+	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 (%s request)\n",
+		task->tk_pid, req ? "pending" : "backlogged");
+
+	task->tk_status  = -ETIMEDOUT;
+out:
+	task->tk_timeout = 0;
+	rpc_wake_up_task(task);
+	spin_unlock(&xprt->sock_lock);
+}
+
+/*
+ * Place the actual RPC call.
+ * We have to copy the iovec because sendmsg fiddles with its contents.
+ */
+int
+xprt_prepare_transmit(struct rpc_task *task)
+{
+	struct rpc_rqst	*req = task->tk_rqstp;
+	struct rpc_xprt	*xprt = req->rq_xprt;
+	int err = 0;
+
+	dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid);
+
+	if (xprt->shutdown)
+		return -EIO;
+
+	spin_lock_bh(&xprt->sock_lock);
+	if (req->rq_received && !req->rq_bytes_sent) {
+		err = req->rq_received;
+		goto out_unlock;
+	}
+	if (!__xprt_lock_write(xprt, task)) {
+		err = -EAGAIN;
+		goto out_unlock;
+	}
+
+	if (!xprt_connected(xprt)) {
+		err = -ENOTCONN;
+		goto out_unlock;
+	}
+out_unlock:
+	spin_unlock_bh(&xprt->sock_lock);
+	return err;
+}
+
+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;
+
+
+	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);
+			/* 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);
+			xprt_reset_majortimeo(req);
+		}
+	} 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;
+	}
+
+	/* Note: at this point, task->tk_sleeping has not yet been set,
+	 *	 hence there is no danger of the waking up task being put on
+	 *	 schedq, and being picked up by a parallel run of rpciod().
+	 */
+	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 -ENOTCONN:
+		return;
+	default:
+		if (xprt->stream)
+			xprt_disconnect(xprt);
+	}
+	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)
+{
+	struct rpc_xprt	*xprt = task->tk_xprt;
+
+	task->tk_status = 0;
+	if (task->tk_rqstp)
+		return;
+	if (!list_empty(&xprt->free)) {
+		struct rpc_rqst	*req = list_entry(xprt->free.next, struct rpc_rqst, rq_list);
+		list_del_init(&req->rq_list);
+		task->tk_rqstp = req;
+		xprt_request_init(task, xprt);
+		return;
+	}
+	dprintk("RPC:      waiting for request slot\n");
+	task->tk_status = -EAGAIN;
+	task->tk_timeout = 0;
+	rpc_sleep_on(&xprt->backlog, task, NULL, NULL);
+}
+
+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);
+		do_xprt_reserve(task);
+		spin_unlock(&xprt->xprt_lock);
+		if (task->tk_rqstp)
+			del_timer_sync(&xprt->timer);
+	}
+}
+
+/*
+ * Allocate a 'unique' XID
+ */
+static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt)
+{
+	return xprt->xid++;
+}
+
+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)
+{
+	struct rpc_rqst	*req = task->tk_rqstp;
+
+	req->rq_timeout = xprt->timeout.to_initval;
+	req->rq_task	= task;
+	req->rq_xprt    = xprt;
+	req->rq_xid     = xprt_alloc_xid(xprt);
+	dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid,
+			req, ntohl(req->rq_xid));
+}
+
+/*
+ * Release an RPC call slot
+ */
+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);
+	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);
+	task->tk_rqstp = NULL;
+	memset(req, 0, sizeof(*req));	/* mark unused */
+
+	dprintk("RPC: %4d release request %p\n", task->tk_pid, req);
+
+	spin_lock(&xprt->xprt_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);
+}
+
+/*
+ * Set constant timeout
+ */
+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_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)
+{
+	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);
+	}
+	spin_lock_init(&xprt->sock_lock);
+	spin_lock_init(&xprt->xprt_lock);
+	init_waitqueue_head(&xprt->cong_wait);
+
+	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_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);
+
+	rpc_init_wait_queue(&xprt->pending, "xprt_pending");
+	rpc_init_wait_queue(&xprt->sending, "xprt_sending");
+	rpc_init_wait_queue(&xprt->resend, "xprt_resend");
+	rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog");
+
+	/* initialize free list */
+	for (req = &xprt->slot[entries-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.
+ */
+struct rpc_xprt *
+xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to)
+{
+	struct rpc_xprt	*xprt;
+
+	xprt = xprt_setup(proto, sap, to);
+	if (IS_ERR(xprt))
+		dprintk("RPC:      xprt_create_proto failed\n");
+	else
+		dprintk("RPC:      xprt_create_proto created xprt %p\n", xprt);
+	return xprt;
+}
+
+/*
+ * Prepare for transport shutdown.
+ */
+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);
+	rpc_wake_up(&xprt->backlog);
+	wake_up(&xprt->cong_wait);
+	del_timer_sync(&xprt->timer);
+}
+
+/*
+ * 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.
+ */
+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);
+	kfree(xprt);
+
+	return 0;
+}