rxrpc: Kill off the call hash table

The call hash table is now no longer used as calls are looked up directly
by channel slot on the connection, so kill it off.
Signed-off-by: David Howells <dhowells@redhat.com>

net/rxrpc/ar-internal.h

@@ -461,19 +461,12 @@ 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		family;		/* Frame protocol */
+	u8			in_clientflag;	/* Copy of conn->in_clientflag */
+	struct rxrpc_local	*local;		/* Local endpoint. */
 	u32			call_id;	/* call ID on connection  */
 	u32			cid;		/* connection ID plus channel index */
 	u32			epoch;		/* epoch of this connection */
 	u16			service_id;	/* service ID */
-	union {					/* Peer IP address for hashing */
-		__be32	ipv4_addr;
-		__u8	ipv6_addr[16];		/* Anticipates eventual IPv6 support */
-	} peer_ip;
 };
 
 /*
@@ -521,8 +514,6 @@ 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(struct rxrpc_host_header *,
-					void *, sa_family_t, const void *);
 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *, unsigned long);
 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
 					 struct rxrpc_conn_parameters *,

net/rxrpc/call_object.c

@@ -14,7 +14,6 @@
 #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>
@@ -61,142 +60,6 @@ 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		in_clientflag,
-	u32		cid,
-	u32		call_id,
-	u32		epoch,
-	u16		service_id,
-	sa_family_t	family,
-	void		*localptr,
-	unsigned int	addr_size,
-	const u8	*peer_addr)
-{
-	const u16 *p;
-	unsigned int i;
-	unsigned long key;
-
-	_enter("");
-
-	key = (unsigned long)localptr;
-	/* We just want to add up the __be32 values, so forcing the
-	 * cast should be okay.
-	 */
-	key += epoch;
-	key += service_id;
-	key += call_id;
-	key += (cid & RXRPC_CIDMASK) >> RXRPC_CIDSHIFT;
-	key += cid & RXRPC_CHANNELMASK;
-	key += in_clientflag;
-	key += family;
-	/* 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->family) {
-	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->family,
-				  call->conn->params.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(
-	struct rxrpc_host_header *hdr,
-	void		*localptr,
-	sa_family_t	family,
-	const void	*peer_addr)
-{
-	unsigned long key;
-	unsigned int addr_size = 0;
-	struct rxrpc_call *call = NULL;
-	struct rxrpc_call *ret = NULL;
-	u8 in_clientflag = hdr->flags & RXRPC_CLIENT_INITIATED;
-
-	_enter("");
-	switch (family) {
-	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(in_clientflag, hdr->cid, hdr->callNumber,
-				  hdr->epoch, hdr->serviceId,
-				  family, 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 == hdr->callNumber &&
-		    call->cid == hdr->cid &&
-		    call->in_clientflag == in_clientflag &&
-		    call->service_id == hdr->serviceId &&
-		    call->family == family &&
-		    call->local == localptr &&
-		    memcmp(call->peer_ip.ipv6_addr, peer_addr,
-			   addr_size) == 0 &&
-		    call->epoch == hdr->epoch) {
-			ret = call;
-			break;
-		}
-	}
-	_leave(" = %p", ret);
-	return ret;
-}
-
 /*
  * find an extant server call
  * - called in process context with IRQs enabled
@@ -305,20 +168,7 @@ static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 	call->socket = rx;
 	call->rx_data_post = 1;
 
-	/* Record copies of information for hashtable lookup */
-	call->family = rx->family;
 	call->local = rx->local;
-	switch (call->family) {
-	case AF_INET:
-		call->peer_ip.ipv4_addr = srx->transport.sin.sin_addr.s_addr;
-		break;
-	case AF_INET6:
-		memcpy(call->peer_ip.ipv6_addr,
-		       srx->transport.sin6.sin6_addr.in6_u.u6_addr8,
-		       sizeof(call->peer_ip.ipv6_addr));
-		break;
-	}
-
 	call->service_id = srx->srx_service;
 	call->in_clientflag = 0;
 
@@ -345,9 +195,6 @@ static int rxrpc_begin_client_call(struct rxrpc_call *call,
 
 	call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
 
-	/* Add the new call to the hashtable */
-	rxrpc_call_hash_add(call);
-
 	spin_lock(&call->conn->params.peer->lock);
 	hlist_add_head(&call->error_link, &call->conn->params.peer->error_targets);
 	spin_unlock(&call->conn->params.peer->lock);
@@ -548,27 +395,10 @@ 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->family = rx->family;
 	call->local = conn->params.local;
-	switch (call->family) {
-	case AF_INET:
-		call->peer_ip.ipv4_addr =
-			conn->params.peer->srx.transport.sin.sin_addr.s_addr;
-		break;
-	case AF_INET6:
-		memcpy(call->peer_ip.ipv6_addr,
-		       conn->params.peer->srx.transport.sin6.sin6_addr.in6_u.u6_addr8,
-		       sizeof(call->peer_ip.ipv6_addr));
-		break;
-	default:
-		break;
-	}
 	call->epoch = conn->proto.epoch;
 	call->service_id = conn->params.service_id;
 	call->in_clientflag = RXRPC_CLIENT_INITIATED;
-	/* 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);
 
@@ -818,9 +648,6 @@ static void rxrpc_cleanup_call(struct rxrpc_call *call)
 
 	ASSERTCMP(call->conn, ==, NULL);
 
-	/* 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,