Merge tag 'rxrpc-devel-20140304' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
net-next: AF_RXRPC fixes and development

Here are some AF_RXRPC fixes:

 (1) Fix to remove incorrect checksum calculation made during recvmsg().  It's
     unnecessary to try to do this there since we check the checksum before
     reading the RxRPC header from the packet.

 (2) Fix to prevent the sending of an ABORT packet in response to another
     ABORT packet and inducing a storm.

 (3) Fix UDP MTU calculation from parsing ICMP_FRAG_NEEDED packets where we
     don't handle the ICMP packet not specifying an MTU size.

And development patches:

 (4) Add sysctls for configuring RxRPC parameters, specifically various delays
     pertaining to ACK generation, the time before we resend a packet for
     which we don't receive an ACK, the maximum time a call is permitted to
     live and the amount of time transport, connection and dead call
     information is cached.

 (5) Improve ACK packet production by adjusting the handling of ACK_REQUESTED
     packets, ignoring the MORE_PACKETS flag, delaying the production of
     otherwise immediate ACK_IDLE packets and delaying all ACK_IDLE production
     (barring the call termination) to half a second.

 (6) Add more sysctl parameters to expose the Rx window size, the maximum
     packet size that we're willing to receive and the number of jumbo rxrpc
     packets we're willing to handle in a single UDP packet.

 (7) Request ACKs on alternate DATA packets so that the other side doesn't
     wait till we fill up the Tx window.

 (8) Use a RCU hash table to look up the rxrpc_call for an incoming packet
     rather than stepping through a hierarchy involving several spinlocks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/rxrpc.txt

@@ -27,6 +27,8 @@ Contents of this document:
 
  (*) AF_RXRPC kernel interface.
 
+ (*) Configurable parameters.
+
 
 ========
 OVERVIEW
@@ -864,3 +866,82 @@ The kernel interface functions are as follows:
 
      This is used to allocate a null RxRPC key that can be used to indicate
      anonymous security for a particular domain.
+
+
+=======================
+CONFIGURABLE PARAMETERS
+=======================
+
+The RxRPC protocol driver has a number of configurable parameters that can be
+adjusted through sysctls in /proc/net/rxrpc/:
+
+ (*) req_ack_delay
+
+     The amount of time in milliseconds after receiving a packet with the
+     request-ack flag set before we honour the flag and actually send the
+     requested ack.
+
+     Usually the other side won't stop sending packets until the advertised
+     reception window is full (to a maximum of 255 packets), so delaying the
+     ACK permits several packets to be ACK'd in one go.
+
+ (*) soft_ack_delay
+
+     The amount of time in milliseconds after receiving a new packet before we
+     generate a soft-ACK to tell the sender that it doesn't need to resend.
+
+ (*) idle_ack_delay
+
+     The amount of time in milliseconds after all the packets currently in the
+     received queue have been consumed before we generate a hard-ACK to tell
+     the sender it can free its buffers, assuming no other reason occurs that
+     we would send an ACK.
+
+ (*) resend_timeout
+
+     The amount of time in milliseconds after transmitting a packet before we
+     transmit it again, assuming no ACK is received from the receiver telling
+     us they got it.
+
+ (*) max_call_lifetime
+
+     The maximum amount of time in seconds that a call may be in progress
+     before we preemptively kill it.
+
+ (*) dead_call_expiry
+
+     The amount of time in seconds before we remove a dead call from the call
+     list.  Dead calls are kept around for a little while for the purpose of
+     repeating ACK and ABORT packets.
+
+ (*) connection_expiry
+
+     The amount of time in seconds after a connection was last used before we
+     remove it from the connection list.  Whilst a connection is in existence,
+     it serves as a placeholder for negotiated security; when it is deleted,
+     the security must be renegotiated.
+
+ (*) transport_expiry
+
+     The amount of time in seconds after a transport was last used before we
+     remove it from the transport list.  Whilst a transport is in existence, it
+     serves to anchor the peer data and keeps the connection ID counter.
+
+ (*) rxrpc_rx_window_size
+
+     The size of the receive window in packets.  This is the maximum number of
+     unconsumed received packets we're willing to hold in memory for any
+     particular call.
+
+ (*) rxrpc_rx_mtu
+
+     The maximum packet MTU size that we're willing to receive in bytes.  This
+     indicates to the peer whether we're willing to accept jumbo packets.
+
+ (*) rxrpc_rx_jumbo_max
+
+     The maximum number of packets that we're willing to accept in a jumbo
+     packet.  Non-terminal packets in a jumbo packet must contain a four byte
+     header plus exactly 1412 bytes of data.  The terminal packet must contain
+     a four byte header plus any amount of data.  In any event, a jumbo packet
+     may not exceed rxrpc_rx_mtu in size.

net/rxrpc/Makefile

@@ -20,9 +20,8 @@ af-rxrpc-y := \
 	ar-skbuff.o \
 	ar-transport.o
 
-ifeq ($(CONFIG_PROC_FS),y)
-af-rxrpc-y += ar-proc.o
-endif
+af-rxrpc-$(CONFIG_PROC_FS) += ar-proc.o
+af-rxrpc-$(CONFIG_SYSCTL) += sysctl.o
 
 obj-$(CONFIG_AF_RXRPC) += af-rxrpc.o
 

net/rxrpc/af_rxrpc.c

@@ -838,6 +838,12 @@ static int __init af_rxrpc_init(void)
 		goto error_key_type_s;
 	}
 
+	ret = rxrpc_sysctl_init();
+	if (ret < 0) {
+		printk(KERN_CRIT "RxRPC: Cannot register sysctls\n");
+		goto error_sysctls;
+	}
+
 #ifdef CONFIG_PROC_FS
 	proc_create("rxrpc_calls", 0, init_net.proc_net, &rxrpc_call_seq_fops);
 	proc_create("rxrpc_conns", 0, init_net.proc_net,
@@ -845,6 +851,8 @@ static int __init af_rxrpc_init(void)
 #endif
 	return 0;
 
+error_sysctls:
+	unregister_key_type(&key_type_rxrpc_s);
 error_key_type_s:
 	unregister_key_type(&key_type_rxrpc);
 error_key_type:
@@ -865,6 +873,7 @@ static int __init af_rxrpc_init(void)
 static void __exit af_rxrpc_exit(void)
 {
 	_enter("");
+	rxrpc_sysctl_exit();
 	unregister_key_type(&key_type_rxrpc_s);
 	unregister_key_type(&key_type_rxrpc);
 	sock_unregister(PF_RXRPC);

net/rxrpc/ar-ack.c

@@ -19,7 +19,49 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
-static unsigned int rxrpc_ack_defer = 1;
+/*
+ * How long to wait before scheduling ACK generation after seeing a
+ * packet with RXRPC_REQUEST_ACK set (in jiffies).
+ */
+unsigned rxrpc_requested_ack_delay = 1;
+
+/*
+ * How long to wait before scheduling an ACK with subtype DELAY (in jiffies).
+ *
+ * We use this when we've received new data packets.  If those packets aren't
+ * all consumed within this time we will send a DELAY ACK if an ACK was not
+ * requested to let the sender know it doesn't need to resend.
+ */
+unsigned rxrpc_soft_ack_delay = 1 * HZ;
+
+/*
+ * How long to wait before scheduling an ACK with subtype IDLE (in jiffies).
+ *
+ * We use this when we've consumed some previously soft-ACK'd packets when
+ * further packets aren't immediately received to decide when to send an IDLE
+ * ACK let the other end know that it can free up its Tx buffer space.
+ */
+unsigned rxrpc_idle_ack_delay = 0.5 * HZ;
+
+/*
+ * Receive window size in packets.  This indicates the maximum number of
+ * unconsumed received packets we're willing to retain in memory.  Once this
+ * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further
+ * packets.
+ */
+unsigned rxrpc_rx_window_size = 32;
+
+/*
+ * Maximum Rx MTU size.  This indicates to the sender the size of jumbo packet
+ * made by gluing normal packets together that we're willing to handle.
+ */
+unsigned rxrpc_rx_mtu = 5692;
+
+/*
+ * The maximum number of fragments in a received jumbo packet that we tell the
+ * sender that we're willing to handle.
+ */
+unsigned rxrpc_rx_jumbo_max = 4;
 
 static const char *rxrpc_acks(u8 reason)
 {
@@ -82,24 +124,23 @@ void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
 	switch (ack_reason) {
 	case RXRPC_ACK_DELAY:
 		_debug("run delay timer");
-		call->ack_timer.expires = jiffies + rxrpc_ack_timeout * HZ;
-		add_timer(&call->ack_timer);
-		return;
+		expiry = rxrpc_soft_ack_delay;
+		goto run_timer;
 
 	case RXRPC_ACK_IDLE:
 		if (!immediate) {
 			_debug("run defer timer");
-			expiry = 1;
+			expiry = rxrpc_idle_ack_delay;
 			goto run_timer;
 		}
 		goto cancel_timer;
 
 	case RXRPC_ACK_REQUESTED:
-		if (!rxrpc_ack_defer)
+		expiry = rxrpc_requested_ack_delay;
+		if (!expiry)
 			goto cancel_timer;
 		if (!immediate || serial == cpu_to_be32(1)) {
 			_debug("run defer timer");
-			expiry = rxrpc_ack_defer;
 			goto run_timer;
 		}
 
@@ -1174,11 +1215,11 @@ void rxrpc_process_call(struct work_struct *work)
 	mtu = call->conn->trans->peer->if_mtu;
 	mtu -= call->conn->trans->peer->hdrsize;
 	ackinfo.maxMTU	= htonl(mtu);
-	ackinfo.rwind	= htonl(32);
+	ackinfo.rwind	= htonl(rxrpc_rx_window_size);
 
 	/* permit the peer to send us jumbo packets if it wants to */
-	ackinfo.rxMTU	= htonl(5692);
-	ackinfo.jumbo_max = htonl(4);
+	ackinfo.rxMTU	= htonl(rxrpc_rx_mtu);
+	ackinfo.jumbo_max = htonl(rxrpc_rx_jumbo_max);
 
 	hdr.serial = htonl(atomic_inc_return(&call->conn->serial));
 	_proto("Tx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",

net/rxrpc/ar-call.c

@@ -12,10 +12,22 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/circ_buf.h>
+#include <linux/hashtable.h>
+#include <linux/spinlock_types.h>
 #include <net/sock.h>
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+/*
+ * Maximum lifetime of a call (in jiffies).
+ */
+unsigned rxrpc_max_call_lifetime = 60 * HZ;
+
+/*
+ * Time till dead call expires after last use (in jiffies).
+ */
+unsigned rxrpc_dead_call_expiry = 2 * HZ;
+
 const char *const rxrpc_call_states[] = {
 	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
 	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
@@ -38,8 +50,6 @@ const char *const rxrpc_call_states[] = {
 struct kmem_cache *rxrpc_call_jar;
 LIST_HEAD(rxrpc_calls);
 DEFINE_RWLOCK(rxrpc_call_lock);
-static unsigned int rxrpc_call_max_lifetime = 60;
-static unsigned int rxrpc_dead_call_timeout = 2;
 
 static void rxrpc_destroy_call(struct work_struct *work);
 static void rxrpc_call_life_expired(unsigned long _call);
@@ -47,6 +57,145 @@ static void rxrpc_dead_call_expired(unsigned long _call);
 static void rxrpc_ack_time_expired(unsigned long _call);
 static void rxrpc_resend_time_expired(unsigned long _call);
 
+static DEFINE_SPINLOCK(rxrpc_call_hash_lock);
+static DEFINE_HASHTABLE(rxrpc_call_hash, 10);
+
+/*
+ * Hash function for rxrpc_call_hash
+ */
+static unsigned long rxrpc_call_hashfunc(
+	u8		clientflag,
+	__be32		cid,
+	__be32		call_id,
+	__be32		epoch,
+	__be16		service_id,
+	sa_family_t	proto,
+	void		*localptr,
+	unsigned int	addr_size,
+	const u8	*peer_addr)
+{
+	const u16 *p;
+	unsigned int i;
+	unsigned long key;
+	u32 hcid = ntohl(cid);
+
+	_enter("");
+
+	key = (unsigned long)localptr;
+	/* We just want to add up the __be32 values, so forcing the
+	 * cast should be okay.
+	 */
+	key += (__force u32)epoch;
+	key += (__force u16)service_id;
+	key += (__force u32)call_id;
+	key += (hcid & RXRPC_CIDMASK) >> RXRPC_CIDSHIFT;
+	key += hcid & RXRPC_CHANNELMASK;
+	key += clientflag;
+	key += proto;
+	/* Step through the peer address in 16-bit portions for speed */
+	for (i = 0, p = (const u16 *)peer_addr; i < addr_size >> 1; i++, p++)
+		key += *p;
+	_leave(" key = 0x%lx", key);
+	return key;
+}
+
+/*
+ * Add a call to the hashtable
+ */
+static void rxrpc_call_hash_add(struct rxrpc_call *call)
+{
+	unsigned long key;
+	unsigned int addr_size = 0;
+
+	_enter("");
+	switch (call->proto) {
+	case AF_INET:
+		addr_size = sizeof(call->peer_ip.ipv4_addr);
+		break;
+	case AF_INET6:
+		addr_size = sizeof(call->peer_ip.ipv6_addr);
+		break;
+	default:
+		break;
+	}
+	key = rxrpc_call_hashfunc(call->in_clientflag, call->cid,
+				  call->call_id, call->epoch,
+				  call->service_id, call->proto,
+				  call->conn->trans->local, addr_size,
+				  call->peer_ip.ipv6_addr);
+	/* Store the full key in the call */
+	call->hash_key = key;
+	spin_lock(&rxrpc_call_hash_lock);
+	hash_add_rcu(rxrpc_call_hash, &call->hash_node, key);
+	spin_unlock(&rxrpc_call_hash_lock);
+	_leave("");
+}
+
+/*
+ * Remove a call from the hashtable
+ */
+static void rxrpc_call_hash_del(struct rxrpc_call *call)
+{
+	_enter("");
+	spin_lock(&rxrpc_call_hash_lock);
+	hash_del_rcu(&call->hash_node);
+	spin_unlock(&rxrpc_call_hash_lock);
+	_leave("");
+}
+
+/*
+ * Find a call in the hashtable and return it, or NULL if it
+ * isn't there.
+ */
+struct rxrpc_call *rxrpc_find_call_hash(
+	u8		clientflag,
+	__be32		cid,
+	__be32		call_id,
+	__be32		epoch,
+	__be16		service_id,
+	void		*localptr,
+	sa_family_t	proto,
+	const u8	*peer_addr)
+{
+	unsigned long key;
+	unsigned int addr_size = 0;
+	struct rxrpc_call *call = NULL;
+	struct rxrpc_call *ret = NULL;
+
+	_enter("");
+	switch (proto) {
+	case AF_INET:
+		addr_size = sizeof(call->peer_ip.ipv4_addr);
+		break;
+	case AF_INET6:
+		addr_size = sizeof(call->peer_ip.ipv6_addr);
+		break;
+	default:
+		break;
+	}
+
+	key = rxrpc_call_hashfunc(clientflag, cid, call_id, epoch,
+				  service_id, proto, localptr, addr_size,
+				  peer_addr);
+	hash_for_each_possible_rcu(rxrpc_call_hash, call, hash_node, key) {
+		if (call->hash_key == key &&
+		    call->call_id == call_id &&
+		    call->cid == cid &&
+		    call->in_clientflag == clientflag &&
+		    call->service_id == service_id &&
+		    call->proto == proto &&
+		    call->local == localptr &&
+		    memcmp(call->peer_ip.ipv6_addr, peer_addr,
+			      addr_size) == 0 &&
+		    call->epoch == epoch) {
+			ret = call;
+			break;
+		}
+	}
+	_leave(" = %p", ret);
+	return ret;
+}
+
 /*
  * allocate a new call
  */
@@ -91,7 +240,7 @@ static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
 	call->rx_data_expect = 1;
 	call->rx_data_eaten = 0;
 	call->rx_first_oos = 0;
-	call->ackr_win_top = call->rx_data_eaten + 1 + RXRPC_MAXACKS;
+	call->ackr_win_top = call->rx_data_eaten + 1 + rxrpc_rx_window_size;
 	call->creation_jif = jiffies;
 	return call;
 }
@@ -128,11 +277,31 @@ static struct rxrpc_call *rxrpc_alloc_client_call(
 		return ERR_PTR(ret);
 	}
 
+	/* Record copies of information for hashtable lookup */
+	call->proto = rx->proto;
+	call->local = trans->local;
+	switch (call->proto) {
+	case AF_INET:
+		call->peer_ip.ipv4_addr =
+			trans->peer->srx.transport.sin.sin_addr.s_addr;
+		break;
+	case AF_INET6:
+		memcpy(call->peer_ip.ipv6_addr,
+		       trans->peer->srx.transport.sin6.sin6_addr.in6_u.u6_addr8,
+		       sizeof(call->peer_ip.ipv6_addr));
+		break;
+	}
+	call->epoch = call->conn->epoch;
+	call->service_id = call->conn->service_id;
+	call->in_clientflag = call->conn->in_clientflag;
+	/* Add the new call to the hashtable */
+	rxrpc_call_hash_add(call);
+
 	spin_lock(&call->conn->trans->peer->lock);
 	list_add(&call->error_link, &call->conn->trans->peer->error_targets);
 	spin_unlock(&call->conn->trans->peer->lock);
 
-	call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
+	call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 	add_timer(&call->lifetimer);
 
 	_leave(" = %p", call);
@@ -320,9 +489,12 @@ struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
 		parent = *p;
 		call = rb_entry(parent, struct rxrpc_call, conn_node);
 
-		if (call_id < call->call_id)
+		/* The tree is sorted in order of the __be32 value without
+		 * turning it into host order.
+		 */
+		if ((__force u32)call_id < (__force u32)call->call_id)
 			p = &(*p)->rb_left;
-		else if (call_id > call->call_id)
+		else if ((__force u32)call_id > (__force u32)call->call_id)
 			p = &(*p)->rb_right;
 		else
 			goto old_call;
@@ -347,9 +519,31 @@ struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
 	list_add_tail(&call->link, &rxrpc_calls);
 	write_unlock_bh(&rxrpc_call_lock);
 
+	/* Record copies of information for hashtable lookup */
+	call->proto = rx->proto;
+	call->local = conn->trans->local;
+	switch (call->proto) {
+	case AF_INET:
+		call->peer_ip.ipv4_addr =
+			conn->trans->peer->srx.transport.sin.sin_addr.s_addr;
+		break;
+	case AF_INET6:
+		memcpy(call->peer_ip.ipv6_addr,
+		       conn->trans->peer->srx.transport.sin6.sin6_addr.in6_u.u6_addr8,
+		       sizeof(call->peer_ip.ipv6_addr));
+		break;
+	default:
+		break;
+	}
+	call->epoch = conn->epoch;
+	call->service_id = conn->service_id;
+	call->in_clientflag = conn->in_clientflag;
+	/* Add the new call to the hashtable */
+	rxrpc_call_hash_add(call);
+
 	_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
 
-	call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
+	call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
 	add_timer(&call->lifetimer);
 	_leave(" = %p {%d} [new]", call, call->debug_id);
 	return call;
@@ -533,7 +727,7 @@ void rxrpc_release_call(struct rxrpc_call *call)
 	del_timer_sync(&call->resend_timer);
 	del_timer_sync(&call->ack_timer);
 	del_timer_sync(&call->lifetimer);
-	call->deadspan.expires = jiffies + rxrpc_dead_call_timeout * HZ;
+	call->deadspan.expires = jiffies + rxrpc_dead_call_expiry;
 	add_timer(&call->deadspan);
 
 	_leave("");
@@ -665,6 +859,9 @@ static void rxrpc_cleanup_call(struct rxrpc_call *call)
 		rxrpc_put_connection(call->conn);
 	}
 
+	/* Remove the call from the hash */
+	rxrpc_call_hash_del(call);
+
 	if (call->acks_window) {
 		_debug("kill Tx window %d",
 		       CIRC_CNT(call->acks_head, call->acks_tail,

net/rxrpc/ar-connection.c

@@ -18,11 +18,15 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+/*
+ * Time till a connection expires after last use (in seconds).
+ */
+unsigned rxrpc_connection_expiry = 10 * 60;
+
 static void rxrpc_connection_reaper(struct work_struct *work);
 
 LIST_HEAD(rxrpc_connections);
 DEFINE_RWLOCK(rxrpc_connection_lock);
-static unsigned long rxrpc_connection_timeout = 10 * 60;
 static DECLARE_DELAYED_WORK(rxrpc_connection_reap, rxrpc_connection_reaper);
 
 /*
@@ -862,7 +866,7 @@ static void rxrpc_connection_reaper(struct work_struct *work)
 
 		spin_lock(&conn->trans->client_lock);
 		write_lock(&conn->trans->conn_lock);
-		reap_time = conn->put_time + rxrpc_connection_timeout;
+		reap_time = conn->put_time + rxrpc_connection_expiry;
 
 		if (atomic_read(&conn->usage) > 0) {
 			;
@@ -916,7 +920,7 @@ void __exit rxrpc_destroy_all_connections(void)
 {
 	_enter("");
 
-	rxrpc_connection_timeout = 0;
+	rxrpc_connection_expiry = 0;
 	cancel_delayed_work(&rxrpc_connection_reap);
 	rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0);
 

net/rxrpc/ar-error.c

@@ -83,6 +83,7 @@ void rxrpc_UDP_error_report(struct sock *sk)
 
 		if (mtu == 0) {
 			/* they didn't give us a size, estimate one */
+			mtu = peer->if_mtu;
 			if (mtu > 1500) {
 				mtu >>= 1;
 				if (mtu < 1500)

net/rxrpc/ar-input.c

@@ -25,8 +25,6 @@
 #include <net/net_namespace.h>
 #include "ar-internal.h"
 
-unsigned long rxrpc_ack_timeout = 1;
-
 const char *rxrpc_pkts[] = {
 	"?00",
 	"DATA", "ACK", "BUSY", "ABORT", "ACKALL", "CHALL", "RESP", "DEBUG",
@@ -349,8 +347,7 @@ void rxrpc_fast_process_packet(struct rxrpc_call *call, struct sk_buff *skb)
 	 * it */
 	if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
 		_proto("ACK Requested on %%%u", serial);
-		rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, sp->hdr.serial,
-				  !(sp->hdr.flags & RXRPC_MORE_PACKETS));
+		rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, sp->hdr.serial, false);
 	}
 
 	switch (sp->hdr.type) {
@@ -526,36 +523,38 @@ static void rxrpc_process_jumbo_packet(struct rxrpc_call *call,
  * post an incoming packet to the appropriate call/socket to deal with
  * - must get rid of the sk_buff, either by freeing it or by queuing it
  */
-static void rxrpc_post_packet_to_call(struct rxrpc_connection *conn,
+static void rxrpc_post_packet_to_call(struct rxrpc_call *call,
 				      struct sk_buff *skb)
 {
 	struct rxrpc_skb_priv *sp;
-	struct rxrpc_call *call;
-	struct rb_node *p;
-	__be32 call_id;
-
-	_enter("%p,%p", conn, skb);
 
-	read_lock_bh(&conn->lock);
+	_enter("%p,%p", call, skb);
 
 	sp = rxrpc_skb(skb);
 
-	/* look at extant calls by channel number first */
-	call = conn->channels[ntohl(sp->hdr.cid) & RXRPC_CHANNELMASK];
-	if (!call || call->call_id != sp->hdr.callNumber)
-		goto call_not_extant;
-
 	_debug("extant call [%d]", call->state);
-	ASSERTCMP(call->conn, ==, conn);
 
 	read_lock(&call->state_lock);
 	switch (call->state) {
 	case RXRPC_CALL_LOCALLY_ABORTED:
-		if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
+		if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events)) {
 			rxrpc_queue_call(call);
+			goto free_unlock;
+		}
 	case RXRPC_CALL_REMOTELY_ABORTED:
 	case RXRPC_CALL_NETWORK_ERROR:
 	case RXRPC_CALL_DEAD:
+		goto dead_call;
+	case RXRPC_CALL_COMPLETE:
+	case RXRPC_CALL_CLIENT_FINAL_ACK:
+		/* complete server call */
+		if (call->conn->in_clientflag)
+			goto dead_call;
+		/* resend last packet of a completed call */
+		_debug("final ack again");
+		rxrpc_get_call(call);
+		set_bit(RXRPC_CALL_ACK_FINAL, &call->events);
+		rxrpc_queue_call(call);
 		goto free_unlock;
 	default:
 		break;
@@ -563,7 +562,6 @@ static void rxrpc_post_packet_to_call(struct rxrpc_connection *conn,
 
 	read_unlock(&call->state_lock);
 	rxrpc_get_call(call);
-	read_unlock_bh(&conn->lock);
 
 	if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 	    sp->hdr.flags & RXRPC_JUMBO_PACKET)
@@ -574,78 +572,16 @@ static void rxrpc_post_packet_to_call(struct rxrpc_connection *conn,
 	rxrpc_put_call(call);
 	goto done;
 
-call_not_extant:
-	/* search the completed calls in case what we're dealing with is
-	 * there */
-	_debug("call not extant");
-
-	call_id = sp->hdr.callNumber;
-	p = conn->calls.rb_node;
-	while (p) {
-		call = rb_entry(p, struct rxrpc_call, conn_node);
-
-		if (call_id < call->call_id)
-			p = p->rb_left;
-		else if (call_id > call->call_id)
-			p = p->rb_right;
-		else
-			goto found_completed_call;
-	}
-
 dead_call:
-	/* it's a either a really old call that we no longer remember or its a
-	 * new incoming call */
-	read_unlock_bh(&conn->lock);
-
-	if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
-	    sp->hdr.seq == cpu_to_be32(1)) {
-		_debug("incoming call");
-		skb_queue_tail(&conn->trans->local->accept_queue, skb);
-		rxrpc_queue_work(&conn->trans->local->acceptor);
-		goto done;
-	}
-
-	_debug("dead call");
-	skb->priority = RX_CALL_DEAD;
-	rxrpc_reject_packet(conn->trans->local, skb);
-	goto done;
-
-	/* resend last packet of a completed call
-	 * - client calls may have been aborted or ACK'd
-	 * - server calls may have been aborted
-	 */
-found_completed_call:
-	_debug("completed call");
-
-	if (atomic_read(&call->usage) == 0)
-		goto dead_call;
-
-	/* synchronise any state changes */
-	read_lock(&call->state_lock);
-	ASSERTIFCMP(call->state != RXRPC_CALL_CLIENT_FINAL_ACK,
-		    call->state, >=, RXRPC_CALL_COMPLETE);
-
-	if (call->state == RXRPC_CALL_LOCALLY_ABORTED ||
-	    call->state == RXRPC_CALL_REMOTELY_ABORTED ||
-	    call->state == RXRPC_CALL_DEAD) {
-		read_unlock(&call->state_lock);
-		goto dead_call;
-	}
-
-	if (call->conn->in_clientflag) {
-		read_unlock(&call->state_lock);
-		goto dead_call; /* complete server call */
+	if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) {
+		skb->priority = RX_CALL_DEAD;
+		rxrpc_reject_packet(call->conn->trans->local, skb);
+		goto unlock;
 	}
-
-	_debug("final ack again");
-	rxrpc_get_call(call);
-	set_bit(RXRPC_CALL_ACK_FINAL, &call->events);
-	rxrpc_queue_call(call);
-
 free_unlock:
-	read_unlock(&call->state_lock);
-	read_unlock_bh(&conn->lock);
 	rxrpc_free_skb(skb);
+unlock:
+	read_unlock(&call->state_lock);
 done:
 	_leave("");
 }
@@ -664,17 +600,42 @@ static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
 	rxrpc_queue_conn(conn);
 }
 
+static struct rxrpc_connection *rxrpc_conn_from_local(struct rxrpc_local *local,
+					       struct sk_buff *skb,
+					       struct rxrpc_skb_priv *sp)
+{
+	struct rxrpc_peer *peer;
+	struct rxrpc_transport *trans;
+	struct rxrpc_connection *conn;
+
+	peer = rxrpc_find_peer(local, ip_hdr(skb)->saddr,
+				udp_hdr(skb)->source);
+	if (IS_ERR(peer))
+		goto cant_find_conn;
+
+	trans = rxrpc_find_transport(local, peer);
+	rxrpc_put_peer(peer);
+	if (!trans)
+		goto cant_find_conn;
+
+	conn = rxrpc_find_connection(trans, &sp->hdr);
+	rxrpc_put_transport(trans);
+	if (!conn)
+		goto cant_find_conn;
+
+	return conn;
+cant_find_conn:
+	return NULL;
+}
+
 /*
  * handle data received on the local endpoint
  * - may be called in interrupt context
  */
 void rxrpc_data_ready(struct sock *sk, int count)
 {
-	struct rxrpc_connection *conn;
-	struct rxrpc_transport *trans;
 	struct rxrpc_skb_priv *sp;
 	struct rxrpc_local *local;
-	struct rxrpc_peer *peer;
 	struct sk_buff *skb;
 	int ret;
 
@@ -749,27 +710,34 @@ void rxrpc_data_ready(struct sock *sk, int count)
 	    (sp->hdr.callNumber == 0 || sp->hdr.seq == 0))
 		goto bad_message;
 
-	peer = rxrpc_find_peer(local, ip_hdr(skb)->saddr, udp_hdr(skb)->source);
-	if (IS_ERR(peer))
-		goto cant_route_call;
+	if (sp->hdr.callNumber == 0) {
+		/* This is a connection-level packet. These should be
+		 * fairly rare, so the extra overhead of looking them up the
+		 * old-fashioned way doesn't really hurt */
+		struct rxrpc_connection *conn;
 
-	trans = rxrpc_find_transport(local, peer);
-	rxrpc_put_peer(peer);
-	if (!trans)
-		goto cant_route_call;
+		conn = rxrpc_conn_from_local(local, skb, sp);
+		if (!conn)
+			goto cant_route_call;
 
-	conn = rxrpc_find_connection(trans, &sp->hdr);
-	rxrpc_put_transport(trans);
-	if (!conn)
-		goto cant_route_call;
-
-	_debug("CONN %p {%d}", conn, conn->debug_id);
-
-	if (sp->hdr.callNumber == 0)
+		_debug("CONN %p {%d}", conn, conn->debug_id);
 		rxrpc_post_packet_to_conn(conn, skb);
-	else
-		rxrpc_post_packet_to_call(conn, skb);
-	rxrpc_put_connection(conn);
+		rxrpc_put_connection(conn);
+	} else {
+		struct rxrpc_call *call;
+		u8 in_clientflag = 0;
+
+		if (sp->hdr.flags & RXRPC_CLIENT_INITIATED)
+			in_clientflag = RXRPC_CLIENT_INITIATED;
+		call = rxrpc_find_call_hash(in_clientflag, sp->hdr.cid,
+					    sp->hdr.callNumber, sp->hdr.epoch,
+					    sp->hdr.serviceId, local, AF_INET,
+					    (u8 *)&ip_hdr(skb)->saddr);
+		if (call)
+			rxrpc_post_packet_to_call(call, skb);
+		else
+			goto cant_route_call;
+	}
 	rxrpc_put_local(local);
 	return;
 
@@ -790,8 +758,10 @@ void rxrpc_data_ready(struct sock *sk, int count)
 		skb->priority = RX_CALL_DEAD;
 	}
 
-	_debug("reject");
-	rxrpc_reject_packet(local, skb);
+	if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) {
+		_debug("reject type %d",sp->hdr.type);
+		rxrpc_reject_packet(local, skb);
+	}
 	rxrpc_put_local(local);
 	_leave(" [no call]");
 	return;

net/rxrpc/ar-internal.h

@@ -396,9 +396,20 @@ struct rxrpc_call {
 #define RXRPC_ACKR_WINDOW_ASZ DIV_ROUND_UP(RXRPC_MAXACKS, BITS_PER_LONG)
 	unsigned long		ackr_window[RXRPC_ACKR_WINDOW_ASZ + 1];
 
+	struct hlist_node	hash_node;
+	unsigned long		hash_key;	/* Full hash key */
+	u8			in_clientflag;	/* Copy of conn->in_clientflag for hashing */
+	struct rxrpc_local	*local;		/* Local endpoint. Used for hashing. */
+	sa_family_t		proto;		/* Frame protocol */
 	/* the following should all be in net order */
 	__be32			cid;		/* connection ID + channel index  */
 	__be32			call_id;	/* call ID on connection  */
+	__be32			epoch;		/* epoch of this connection */
+	__be16			service_id;	/* service ID */
+	union {					/* Peer IP address for hashing */
+		__be32	ipv4_addr;
+		__u8	ipv6_addr[16];		/* Anticipates eventual IPv6 support */
+	} peer_ip;
 };
 
 /*
@@ -433,6 +444,13 @@ int rxrpc_reject_call(struct rxrpc_sock *);
 /*
  * ar-ack.c
  */
+extern unsigned rxrpc_requested_ack_delay;
+extern unsigned rxrpc_soft_ack_delay;
+extern unsigned rxrpc_idle_ack_delay;
+extern unsigned rxrpc_rx_window_size;
+extern unsigned rxrpc_rx_mtu;
+extern unsigned rxrpc_rx_jumbo_max;
+
 void __rxrpc_propose_ACK(struct rxrpc_call *, u8, __be32, bool);
 void rxrpc_propose_ACK(struct rxrpc_call *, u8, __be32, bool);
 void rxrpc_process_call(struct work_struct *);
@@ -440,10 +458,14 @@ void rxrpc_process_call(struct work_struct *);
 /*
  * ar-call.c
  */
+extern unsigned rxrpc_max_call_lifetime;
+extern unsigned rxrpc_dead_call_expiry;
 extern struct kmem_cache *rxrpc_call_jar;
 extern struct list_head rxrpc_calls;
 extern rwlock_t rxrpc_call_lock;
 
+struct rxrpc_call *rxrpc_find_call_hash(u8,  __be32, __be32, __be32,
+					__be16, void *, sa_family_t, const u8 *);
 struct rxrpc_call *rxrpc_get_client_call(struct rxrpc_sock *,
 					 struct rxrpc_transport *,
 					 struct rxrpc_conn_bundle *,
@@ -460,6 +482,7 @@ void __exit rxrpc_destroy_all_calls(void);
 /*
  * ar-connection.c
  */
+extern unsigned rxrpc_connection_expiry;
 extern struct list_head rxrpc_connections;
 extern rwlock_t rxrpc_connection_lock;
 
@@ -493,7 +516,6 @@ void rxrpc_UDP_error_handler(struct work_struct *);
 /*
  * ar-input.c
  */
-extern unsigned long rxrpc_ack_timeout;
 extern const char *rxrpc_pkts[];
 
 void rxrpc_data_ready(struct sock *, int);
@@ -504,6 +526,7 @@ void rxrpc_fast_process_packet(struct rxrpc_call *, struct sk_buff *);
  * ar-local.c
  */
 extern rwlock_t rxrpc_local_lock;
+
 struct rxrpc_local *rxrpc_lookup_local(struct sockaddr_rxrpc *);
 void rxrpc_put_local(struct rxrpc_local *);
 void __exit rxrpc_destroy_all_locals(void);
@@ -522,7 +545,7 @@ int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time_t,
 /*
  * ar-output.c
  */
-extern int rxrpc_resend_timeout;
+extern unsigned rxrpc_resend_timeout;
 
 int rxrpc_send_packet(struct rxrpc_transport *, struct sk_buff *);
 int rxrpc_client_sendmsg(struct kiocb *, struct rxrpc_sock *,
@@ -572,6 +595,8 @@ void rxrpc_packet_destructor(struct sk_buff *);
 /*
  * ar-transport.c
  */
+extern unsigned rxrpc_transport_expiry;
+
 struct rxrpc_transport *rxrpc_get_transport(struct rxrpc_local *,
 					    struct rxrpc_peer *, gfp_t);
 void rxrpc_put_transport(struct rxrpc_transport *);
@@ -579,6 +604,17 @@ void __exit rxrpc_destroy_all_transports(void);
 struct rxrpc_transport *rxrpc_find_transport(struct rxrpc_local *,
 					     struct rxrpc_peer *);
 
+/*
+ * sysctl.c
+ */
+#ifdef CONFIG_SYSCTL
+extern int __init rxrpc_sysctl_init(void);
+extern void rxrpc_sysctl_exit(void);
+#else
+static inline int __init rxrpc_sysctl_init(void) { return 0; }
+static inline void rxrpc_sysctl_exit(void) {}
+#endif
+
 /*
  * debug tracing
  */

net/rxrpc/ar-output.c

@@ -18,7 +18,10 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
-int rxrpc_resend_timeout = 4;
+/*
+ * Time till packet resend (in jiffies).
+ */
+unsigned rxrpc_resend_timeout = 4 * HZ;
 
 static int rxrpc_send_data(struct kiocb *iocb,
 			   struct rxrpc_sock *rx,
@@ -487,7 +490,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 	       ntohl(sp->hdr.serial), ntohl(sp->hdr.seq));
 
 	sp->need_resend = false;
-	sp->resend_at = jiffies + rxrpc_resend_timeout * HZ;
+	sp->resend_at = jiffies + rxrpc_resend_timeout;
 	if (!test_and_set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags)) {
 		_debug("run timer");
 		call->resend_timer.expires = sp->resend_at;
@@ -666,6 +669,7 @@ static int rxrpc_send_data(struct kiocb *iocb,
 		/* add the packet to the send queue if it's now full */
 		if (sp->remain <= 0 || (segment == 0 && !more)) {
 			struct rxrpc_connection *conn = call->conn;
+			uint32_t seq;
 			size_t pad;
 
 			/* pad out if we're using security */
@@ -678,11 +682,12 @@ static int rxrpc_send_data(struct kiocb *iocb,
 					memset(skb_put(skb, pad), 0, pad);
 			}
 
+			seq = atomic_inc_return(&call->sequence);
+
 			sp->hdr.epoch = conn->epoch;
 			sp->hdr.cid = call->cid;
 			sp->hdr.callNumber = call->call_id;
-			sp->hdr.seq =
-				htonl(atomic_inc_return(&call->sequence));
+			sp->hdr.seq = htonl(seq);
 			sp->hdr.serial =
 				htonl(atomic_inc_return(&conn->serial));
 			sp->hdr.type = RXRPC_PACKET_TYPE_DATA;
@@ -697,6 +702,8 @@ static int rxrpc_send_data(struct kiocb *iocb,
 			else if (CIRC_SPACE(call->acks_head, call->acks_tail,
 					    call->acks_winsz) > 1)
 				sp->hdr.flags |= RXRPC_MORE_PACKETS;
+			if (more && seq & 1)
+				sp->hdr.flags |= RXRPC_REQUEST_ACK;
 
 			ret = rxrpc_secure_packet(
 				call, skb, skb->mark,

net/rxrpc/ar-recvmsg.c

@@ -180,16 +180,7 @@ int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock,
 		if (copy > len - copied)
 			copy = len - copied;
 
-		if (skb->ip_summed == CHECKSUM_UNNECESSARY ||
-		    skb->ip_summed == CHECKSUM_PARTIAL) {
-			ret = skb_copy_datagram_iovec(skb, offset,
-						      msg->msg_iov, copy);
-		} else {
-			ret = skb_copy_and_csum_datagram_iovec(skb, offset,
-							       msg->msg_iov);
-			if (ret == -EINVAL)
-				goto csum_copy_error;
-		}
+		ret = skb_copy_datagram_iovec(skb, offset, msg->msg_iov, copy);
 
 		if (ret < 0)
 			goto copy_error;
@@ -348,20 +339,6 @@ int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock,
 	_leave(" = %d", ret);
 	return ret;
 
-csum_copy_error:
-	_debug("csum error");
-	release_sock(&rx->sk);
-	if (continue_call)
-		rxrpc_put_call(continue_call);
-	rxrpc_kill_skb(skb);
-	if (!(flags & MSG_PEEK)) {
-		if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
-			BUG();
-	}
-	skb_kill_datagram(&rx->sk, skb, flags);
-	rxrpc_put_call(call);
-	return -EAGAIN;
-
 wait_interrupted:
 	ret = sock_intr_errno(timeo);
 wait_error:

net/rxrpc/ar-skbuff.c

@@ -83,9 +83,14 @@ static void rxrpc_hard_ACK_data(struct rxrpc_call *call,
 		rxrpc_request_final_ACK(call);
 	} else if (atomic_dec_and_test(&call->ackr_not_idle) &&
 		   test_and_clear_bit(RXRPC_CALL_TX_SOFT_ACK, &call->flags)) {
+		/* We previously soft-ACK'd some received packets that have now
+		 * been consumed, so send a hard-ACK if no more packets are
+		 * immediately forthcoming to allow the transmitter to free up
+		 * its Tx bufferage.
+		 */
 		_debug("send Rx idle ACK");
 		__rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, sp->hdr.serial,
-				    true);
+				    false);
 	}
 
 	spin_unlock_bh(&call->lock);

net/rxrpc/ar-transport.c

@@ -17,11 +17,15 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+/*
+ * Time after last use at which transport record is cleaned up.
+ */
+unsigned rxrpc_transport_expiry = 3600 * 24;
+
 static void rxrpc_transport_reaper(struct work_struct *work);
 
 static LIST_HEAD(rxrpc_transports);
 static DEFINE_RWLOCK(rxrpc_transport_lock);
-static unsigned long rxrpc_transport_timeout = 3600 * 24;
 static DECLARE_DELAYED_WORK(rxrpc_transport_reap, rxrpc_transport_reaper);
 
 /*
@@ -235,7 +239,7 @@ static void rxrpc_transport_reaper(struct work_struct *work)
 		if (likely(atomic_read(&trans->usage) > 0))
 			continue;
 
-		reap_time = trans->put_time + rxrpc_transport_timeout;
+		reap_time = trans->put_time + rxrpc_transport_expiry;
 		if (reap_time <= now)
 			list_move_tail(&trans->link, &graveyard);
 		else if (reap_time < earliest)
@@ -271,7 +275,7 @@ void __exit rxrpc_destroy_all_transports(void)
 {
 	_enter("");
 
-	rxrpc_transport_timeout = 0;
+	rxrpc_transport_expiry = 0;
 	cancel_delayed_work(&rxrpc_transport_reap);
 	rxrpc_queue_delayed_work(&rxrpc_transport_reap, 0);
 

net/rxrpc/sysctl.c

+/* sysctls for configuring RxRPC operating parameters
+ *
+ * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/sysctl.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+static struct ctl_table_header *rxrpc_sysctl_reg_table;
+static const unsigned zero = 0;
+static const unsigned one = 1;
+static const unsigned four = 4;
+static const unsigned n_65535 = 65535;
+static const unsigned n_max_acks = RXRPC_MAXACKS;
+
+/*
+ * RxRPC operating parameters.
+ *
+ * See Documentation/networking/rxrpc.txt and the variable definitions for more
+ * information on the individual parameters.
+ */
+static struct ctl_table rxrpc_sysctl_table[] = {
+	/* Values measured in milliseconds */
+	{
+		.procname	= "req_ack_delay",
+		.data		= &rxrpc_requested_ack_delay,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_ms_jiffies,
+		.extra1		= (void *)&zero,
+	},
+	{
+		.procname	= "soft_ack_delay",
+		.data		= &rxrpc_soft_ack_delay,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_ms_jiffies,
+		.extra1		= (void *)&one,
+	},
+	{
+		.procname	= "idle_ack_delay",
+		.data		= &rxrpc_idle_ack_delay,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_ms_jiffies,
+		.extra1		= (void *)&one,
+	},
+	{
+		.procname	= "resend_timeout",
+		.data		= &rxrpc_resend_timeout,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_ms_jiffies,
+		.extra1		= (void *)&one,
+	},
+
+	/* Values measured in seconds but used in jiffies */
+	{
+		.procname	= "max_call_lifetime",
+		.data		= &rxrpc_max_call_lifetime,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+		.extra1		= (void *)&one,
+	},
+	{
+		.procname	= "dead_call_expiry",
+		.data		= &rxrpc_dead_call_expiry,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+		.extra1		= (void *)&one,
+	},
+
+	/* Values measured in seconds */
+	{
+		.procname	= "connection_expiry",
+		.data		= &rxrpc_connection_expiry,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= (void *)&one,
+	},
+	{
+		.procname	= "transport_expiry",
+		.data		= &rxrpc_transport_expiry,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= (void *)&one,
+	},
+
+	/* Non-time values */
+	{
+		.procname	= "rx_window_size",
+		.data		= &rxrpc_rx_window_size,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= (void *)&one,
+		.extra2		= (void *)&n_max_acks,
+	},
+	{
+		.procname	= "rx_mtu",
+		.data		= &rxrpc_rx_mtu,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= (void *)&one,
+		.extra1		= (void *)&n_65535,
+	},
+	{
+		.procname	= "rx_jumbo_max",
+		.data		= &rxrpc_rx_jumbo_max,
+		.maxlen		= sizeof(unsigned),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= (void *)&one,
+		.extra2		= (void *)&four,
+	},
+
+	{ }
+};
+
+int __init rxrpc_sysctl_init(void)
+{
+	rxrpc_sysctl_reg_table = register_net_sysctl(&init_net, "net/rxrpc",
+						     rxrpc_sysctl_table);
+	if (!rxrpc_sysctl_reg_table)
+		return -ENOMEM;
+	return 0;
+}
+
+void rxrpc_sysctl_exit(void)
+{
+	if (rxrpc_sysctl_reg_table)
+		unregister_net_sysctl_table(rxrpc_sysctl_reg_table);
+}