patch-2.3.99-pre6 linux/net/atm/mpoa_caches.c

• Lines: 948
• Date: Fri Apr 14 09:48:47 2000
• Orig file: v2.3.99-pre5/linux/net/atm/mpoa_caches.c
• Orig date: Thu Feb 10 17:11:23 2000

diff -u --recursive --new-file v2.3.99-pre5/linux/net/atm/mpoa_caches.c linux/net/atm/mpoa_caches.c
@@ -22,165 +22,159 @@
 #define ddprintk(format,args...)
 #endif
 
-static in_cache_entry *in_cache_search(uint32_t dst_ip, 
-				       struct mpoa_client *client)
+static in_cache_entry *in_cache_get(uint32_t dst_ip,
+				    struct mpoa_client *client)
 {
-        unsigned long flags;
-        in_cache_entry *entry;
+	in_cache_entry *entry;
 
-        read_lock_irqsave(&client->ingress_lock, flags);
-        entry = client->in_cache;
-        while(entry != NULL){
-                if( entry->ctrl_info.in_dst_ip == dst_ip ){
-                        read_unlock_irqrestore(&client->ingress_lock, flags);
-                        return entry;
-                }
-                entry = entry->next;
-        }
-        read_unlock_irqrestore(&client->ingress_lock, flags);
-
-        return NULL;
-}
-
-static in_cache_entry *in_cache_search_with_mask(uint32_t dst_ip,
-						 struct mpoa_client *client,
-						 uint32_t mask){
-        unsigned long flags;
-        in_cache_entry *entry;
-
-        read_lock_irqsave(&client->ingress_lock, flags);
-        entry = client->in_cache;
-        while(entry != NULL){
-                if((entry->ctrl_info.in_dst_ip & mask)  == (dst_ip & mask )){
-                        read_unlock_irqrestore(&client->ingress_lock, flags);
-                        return entry;
-                }
-                entry = entry->next;
-        }
-        read_unlock_irqrestore(&client->ingress_lock, flags);
-
-        return NULL;
-  
-}
-
-static in_cache_entry *in_cache_search_by_vcc(struct atm_vcc *vcc, 
-					      struct mpoa_client *client )
-{
-        unsigned long flags;
-        in_cache_entry *entry;
-
-        read_lock_irqsave(&client->ingress_lock, flags);
-        entry = client->in_cache;
-        while(entry != NULL){
-	        if(entry->shortcut == vcc) {
-                        read_unlock_irqrestore(&client->ingress_lock, flags);
-		        return entry;
-                }
+	read_lock_bh(&client->ingress_lock);
+	entry = client->in_cache;
+	while(entry != NULL){
+		if( entry->ctrl_info.in_dst_ip == dst_ip ){
+			atomic_inc(&entry->use);
+			read_unlock_bh(&client->ingress_lock);
+			return entry;
+		}
+		entry = entry->next;
+	}
+	read_unlock_bh(&client->ingress_lock);
+
+	return NULL;
+}
+
+static in_cache_entry *in_cache_get_with_mask(uint32_t dst_ip,
+					      struct mpoa_client *client,
+					      uint32_t mask)
+{
+	in_cache_entry *entry;
+
+	read_lock_bh(&client->ingress_lock);
+	entry = client->in_cache;
+	while(entry != NULL){
+		if((entry->ctrl_info.in_dst_ip & mask)  == (dst_ip & mask )){
+			atomic_inc(&entry->use);
+			read_unlock_bh(&client->ingress_lock);
+			return entry;
+		}
+		entry = entry->next;
+	}
+	read_unlock_bh(&client->ingress_lock);
+
+	return NULL;
+
+}
+
+static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc,
+					   struct mpoa_client *client )
+{
+	in_cache_entry *entry;
+
+	read_lock_bh(&client->ingress_lock);
+	entry = client->in_cache;
+	while(entry != NULL){
+		if(entry->shortcut == vcc) {
+			atomic_inc(&entry->use);
+			read_unlock_bh(&client->ingress_lock);
+			return entry;
+		}
 		entry = entry->next;
-        }
-        read_unlock_irqrestore(&client->ingress_lock, flags);
+	}
+	read_unlock_bh(&client->ingress_lock);
 
-        return NULL;
+	return NULL;
 }
 
-static in_cache_entry *new_in_cache_entry(uint32_t dst_ip, 
+static in_cache_entry *in_cache_add_entry(uint32_t dst_ip,
 					  struct mpoa_client *client)
 {
-        unsigned long flags;
-        unsigned char *ip __attribute__ ((unused)) = (unsigned char *)&dst_ip;
-        in_cache_entry* entry = kmalloc(sizeof(in_cache_entry), GFP_KERNEL);
-
-        if (entry == NULL) {
-                printk("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n");
-                return NULL;
-        }
-
-        dprintk("mpoa: mpoa_caches.c: adding an ingress entry, ip = %u.%u.%u.%u\n", ip[0], ip[1], ip[2], ip[3]);
-        memset(entry,0,sizeof(in_cache_entry));
-
-        dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: about to lock\n");
-        write_lock_irqsave(&client->ingress_lock, flags);
-        entry->next = client->in_cache;
-        entry->prev = NULL;
-        if (client->in_cache != NULL)
-                client->in_cache->prev = entry;
-        client->in_cache = entry;
-        write_unlock_irqrestore(&client->ingress_lock, flags);
-        dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: unlocked\n");
-
-        memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
-        entry->ctrl_info.in_dst_ip = dst_ip;
-        do_gettimeofday(&(entry->tv));
-        entry->retry_time = client->parameters.mpc_p4;
-        entry->count = 1;
-        entry->entry_state = INGRESS_INVALID; 
-        entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
+	unsigned char *ip __attribute__ ((unused)) = (unsigned char *)&dst_ip;
+	in_cache_entry* entry = kmalloc(sizeof(in_cache_entry), GFP_KERNEL);
+
+	if (entry == NULL) {
+		printk("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n");
+		return NULL;
+	}
+
+	dprintk("mpoa: mpoa_caches.c: adding an ingress entry, ip = %u.%u.%u.%u\n", ip[0], ip[1], ip[2], ip[3]);
+	memset(entry,0,sizeof(in_cache_entry));
+
+	atomic_set(&entry->use, 1);
+	dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: about to lock\n");
+	write_lock_bh(&client->ingress_lock);
+	entry->next = client->in_cache;
+	entry->prev = NULL;
+	if (client->in_cache != NULL)
+		client->in_cache->prev = entry;
+	client->in_cache = entry;
+
+	memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
+	entry->ctrl_info.in_dst_ip = dst_ip;
+	do_gettimeofday(&(entry->tv));
+	entry->retry_time = client->parameters.mpc_p4;
+	entry->count = 1;
+	entry->entry_state = INGRESS_INVALID;
+	entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
+	atomic_inc(&entry->use);
+
+	write_unlock_bh(&client->ingress_lock);
+	dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: unlocked\n");
 
 	return entry;
 }
 
-static int cache_hit( in_cache_entry * entry, struct mpoa_client *mpc)
+static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc)
 {
-        struct atm_mpoa_qos *qos;
-        struct k_message msg;
+	struct atm_mpoa_qos *qos;
+	struct k_message msg;
 
-        entry->count++;
+	entry->count++;
 	if(entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL)
-                return OPEN;
+		return OPEN;
 
 	if(entry->entry_state == INGRESS_REFRESHING){
-	        if(entry->count > mpc->parameters.mpc_p1){
-		        msg.type = SND_MPOA_RES_RQST;
+		if(entry->count > mpc->parameters.mpc_p1){
+			msg.type = SND_MPOA_RES_RQST;
 			msg.content.in_info = entry->ctrl_info;
 			memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
-                        qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
-                        if (qos != NULL) msg.qos = qos->qos;
+			qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
+			if (qos != NULL) msg.qos = qos->qos;
 			msg_to_mpoad(&msg, mpc);
 			do_gettimeofday(&(entry->reply_wait));
 			entry->entry_state = INGRESS_RESOLVING;
 		}
 		if(entry->shortcut != NULL)
-                        return OPEN;
+			return OPEN;
 		return CLOSED;
 	}
 
-        if(entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL)
-	        return OPEN;
+	if(entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL)
+		return OPEN;
 
-        if( entry->count > mpc->parameters.mpc_p1 &&
-            entry->entry_state == INGRESS_INVALID){
-                unsigned char *ip __attribute__ ((unused)) =
+	if( entry->count > mpc->parameters.mpc_p1 &&
+	    entry->entry_state == INGRESS_INVALID){
+		unsigned char *ip __attribute__ ((unused)) =
 		    (unsigned char *)&entry->ctrl_info.in_dst_ip;
 
 		dprintk("mpoa: (%s) mpoa_caches.c: threshold exceeded for ip %u.%u.%u.%u, sending MPOA res req\n", mpc->dev->name, ip[0], ip[1], ip[2], ip[3]);
-                entry->entry_state = INGRESS_RESOLVING;
-                msg.type =  SND_MPOA_RES_RQST;
-                memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN );
-                msg.content.in_info = entry->ctrl_info;
-                qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
-                if (qos != NULL) msg.qos = qos->qos;
-                msg_to_mpoad( &msg, mpc);
-                do_gettimeofday(&(entry->reply_wait));
-        }
+		entry->entry_state = INGRESS_RESOLVING;
+		msg.type =  SND_MPOA_RES_RQST;
+		memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN );
+		msg.content.in_info = entry->ctrl_info;
+		qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
+		if (qos != NULL) msg.qos = qos->qos;
+		msg_to_mpoad( &msg, mpc);
+		do_gettimeofday(&(entry->reply_wait));
+	}
 
-        return CLOSED;
+	return CLOSED;
 }
 
-/*
- * If there are no more references to vcc in egress cache,
- * we are ready to close it.
- */
-static void close_unused_egress_vcc(struct atm_vcc *vcc, struct mpoa_client *mpc)
+static void in_cache_put(in_cache_entry *entry)
 {
-	if (vcc == NULL)
-		return;
-
-	dprintk("mpoa: mpoa_caches.c: close_unused_egress_vcc:\n");
-        if (mpc->eg_ops->search_by_vcc(vcc, mpc) != NULL)
-                return;                             /* entry still in use */
-
-	atm_async_release_vcc(vcc, -EPIPE); /* nobody uses this VCC anymore, close it */
-	dprintk("mpoa: mpoa_caches.c: close_unused_egress_vcc, closed one:\n");
+	if (atomic_dec_and_test(&entry->use)) {
+		memset(entry, 0, sizeof(in_cache_entry));
+		kfree(entry);
+	}
 
 	return;
 }
@@ -188,371 +182,395 @@
 /*
  * This should be called with write lock on
  */
-static int in_cache_remove( in_cache_entry *entry,
-                            struct mpoa_client *client )
+static void in_cache_remove_entry(in_cache_entry *entry,
+				  struct mpoa_client *client)
 {
 	struct atm_vcc *vcc;
-        struct k_message msg;
-        unsigned char *ip;
-
-        if(entry == NULL)
-                return 0;
+	struct k_message msg;
+	unsigned char *ip;
 
 	vcc = entry->shortcut;
-        ip = (unsigned char *)&entry->ctrl_info.in_dst_ip;
-        dprintk("mpoa: mpoa_caches.c: removing an ingress entry, ip = %u.%u.%u.%u\n",ip[0], ip[1], ip[2], ip[3]);
+	ip = (unsigned char *)&entry->ctrl_info.in_dst_ip;
+	dprintk("mpoa: mpoa_caches.c: removing an ingress entry, ip = %u.%u.%u.%u\n",ip[0], ip[1], ip[2], ip[3]);
 
-        if (entry->prev != NULL)
-                entry->prev->next = entry->next;
-        else
-                client->in_cache = entry->next;
-        if (entry->next != NULL)
-                entry->next->prev = entry->prev;
-        memset(entry, 0, sizeof(in_cache_entry));
-        kfree(entry);
+	if (entry->prev != NULL)
+		entry->prev->next = entry->next;
+	else
+		client->in_cache = entry->next;
+	if (entry->next != NULL)
+		entry->next->prev = entry->prev;
+	client->in_ops->put(entry);
 	if(client->in_cache == NULL && client->eg_cache == NULL){
-	        msg.type = STOP_KEEP_ALIVE_SM;
+		msg.type = STOP_KEEP_ALIVE_SM;
 		msg_to_mpoad(&msg,client);
 	}
 
-	close_unused_egress_vcc(vcc, client);
-        return 1;
-} 
+	/* Check if the egress side still uses this VCC */
+	if (vcc != NULL) {
+		eg_cache_entry *eg_entry = client->eg_ops->get_by_vcc(vcc, client);
+		if (eg_entry != NULL) {
+			client->eg_ops->put(eg_entry);
+			return;
+		}
+		atm_async_release_vcc(vcc, -EPIPE);
+	}
+
+	return;
+}
 
 
-/* Call this every MPC-p2 seconds... Not exactly correct solution, 
+/* Call this every MPC-p2 seconds... Not exactly correct solution,
    but an easy one... */
-
 static void clear_count_and_expired(struct mpoa_client *client)
 {
-        unsigned char *ip;
-        unsigned long flags;
-        in_cache_entry *entry, *next_entry;
-        struct timeval now;
+	unsigned char *ip;
+	in_cache_entry *entry, *next_entry;
+	struct timeval now;
 
 	do_gettimeofday(&now);
-        
-        write_lock_irqsave(&client->ingress_lock, flags);
-        entry = client->in_cache;
-        while(entry != NULL){
-                entry->count=0;
-                next_entry = entry->next;
-                if((now.tv_sec - entry->tv.tv_sec) 
-                   > entry->ctrl_info.holding_time){
-		        ip = (unsigned char*)&entry->ctrl_info.in_dst_ip;
-		        dprintk("mpoa: mpoa_caches.c: holding time expired, ip = %d.%d.%d.%d\n", ip[0], ip[1], ip[2], ip[3]);
-                        in_cache_remove(entry, client);
-                }
-                entry = next_entry;
-        }
-        write_unlock_irqrestore(&client->ingress_lock, flags);
-
-        return;
-}
-
-/* Call this every MPC-p4 seconds. */ 
-
-static void check_resolving_entries( struct mpoa_client * client )
-{
-
-        struct atm_mpoa_qos *qos;
-        unsigned long flags;
-        in_cache_entry *entry;
-        struct timeval now;
-        struct k_message msg;
+
+	write_lock_bh(&client->ingress_lock);
+	entry = client->in_cache;
+	while(entry != NULL){
+		entry->count=0;
+		next_entry = entry->next;
+		if((now.tv_sec - entry->tv.tv_sec)
+		   > entry->ctrl_info.holding_time){
+			ip = (unsigned char*)&entry->ctrl_info.in_dst_ip;
+			dprintk("mpoa: mpoa_caches.c: holding time expired, ip = %u.%u.%u.%u\n", NIPQUAD(ip));
+			client->in_ops->remove_entry(entry, client);
+		}
+		entry = next_entry;
+	}
+	write_unlock_bh(&client->ingress_lock);
+
+	return;
+}
+
+/* Call this every MPC-p4 seconds. */
+static void check_resolving_entries(struct mpoa_client *client)
+{
+
+	struct atm_mpoa_qos *qos;
+	in_cache_entry *entry;
+	struct timeval now;
+	struct k_message msg;
 
 	do_gettimeofday( &now );
 
-        read_lock_irqsave(&client->ingress_lock, flags);
-        entry = client->in_cache;
-        while( entry != NULL ){
-                if(entry->entry_state == INGRESS_RESOLVING){
-                        if(now.tv_sec - entry->hold_down.tv_sec < client->parameters.mpc_p6){
-                                entry = entry->next;                      /* Entry in hold down */
-                                continue;
-                        }
-                        if( (now.tv_sec - entry->reply_wait.tv_sec) >
-                            entry->retry_time ){
-                                entry->retry_time = MPC_C1*( entry->retry_time );
-                                if(entry->retry_time > client->parameters.mpc_p5){
-				        /* Retry time maximum exceeded, put entry in hold down. */  
-				        do_gettimeofday(&(entry->hold_down)); 
-                                        entry->retry_time = client->parameters.mpc_p4; 
-                                        entry = entry->next;
-                                        continue;
-                                }
+	read_lock_bh(&client->ingress_lock);
+	entry = client->in_cache;
+	while( entry != NULL ){
+		if(entry->entry_state == INGRESS_RESOLVING){
+			if(now.tv_sec - entry->hold_down.tv_sec < client->parameters.mpc_p6){
+				entry = entry->next;                      /* Entry in hold down */
+				continue;
+			}
+			if( (now.tv_sec - entry->reply_wait.tv_sec) >
+			    entry->retry_time ){
+				entry->retry_time = MPC_C1*( entry->retry_time );
+				if(entry->retry_time > client->parameters.mpc_p5){
+					/* Retry time maximum exceeded, put entry in hold down. */
+					do_gettimeofday(&(entry->hold_down));
+					entry->retry_time = client->parameters.mpc_p4;
+					entry = entry->next;
+					continue;
+				}
 				/* Ask daemon to send a resolution request. */
-                                memset(&(entry->hold_down),0,sizeof(struct timeval));
-                                msg.type = SND_MPOA_RES_RTRY;
-                                memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN);
-                                msg.content.in_info = entry->ctrl_info;
-                                qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
-                                if (qos != NULL) msg.qos = qos->qos;
-                                msg_to_mpoad(&msg, client);
-                                do_gettimeofday(&(entry->reply_wait));
-                        }
-                }
-                entry = entry->next;
-        }
-        read_unlock_irqrestore(&client->ingress_lock, flags);
+				memset(&(entry->hold_down),0,sizeof(struct timeval));
+				msg.type = SND_MPOA_RES_RTRY;
+				memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN);
+				msg.content.in_info = entry->ctrl_info;
+				qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
+				if (qos != NULL) msg.qos = qos->qos;
+				msg_to_mpoad(&msg, client);
+				do_gettimeofday(&(entry->reply_wait));
+			}
+		}
+		entry = entry->next;
+	}
+	read_unlock_bh(&client->ingress_lock);
 }
 
 /* Call this every MPC-p5 seconds. */
-
-static void refresh_entries( struct mpoa_client * client )
+static void refresh_entries(struct mpoa_client *client)
 {
-        unsigned long flags;
-        struct timeval now;
-        struct in_cache_entry *entry = client->in_cache;
-        
-        ddprintk("mpoa: mpoa_caches.c: refresh_entries\n");
+	struct timeval now;
+	struct in_cache_entry *entry = client->in_cache;
+
+	ddprintk("mpoa: mpoa_caches.c: refresh_entries\n");
 	do_gettimeofday(&now);
 
-        read_lock_irqsave(&client->ingress_lock, flags);
-        while( entry != NULL ){
-                if( entry->entry_state == INGRESS_RESOLVED ){
-                        if(!(entry->refresh_time))
-			        entry->refresh_time = (2*(entry->ctrl_info.holding_time))/3;
+	read_lock_bh(&client->ingress_lock);
+	while( entry != NULL ){
+		if( entry->entry_state == INGRESS_RESOLVED ){
+			if(!(entry->refresh_time))
+				entry->refresh_time = (2*(entry->ctrl_info.holding_time))/3;
 			if( (now.tv_sec - entry->reply_wait.tv_sec) > entry->refresh_time ){
-                                dprintk("mpoa: mpoa_caches.c: refreshing an entry.\n");
+				dprintk("mpoa: mpoa_caches.c: refreshing an entry.\n");
 				entry->entry_state = INGRESS_REFRESHING;
-                                
+
 			}
-                }
-                entry = entry->next;
-        }
-        read_unlock_irqrestore(&client->ingress_lock, flags);
+		}
+		entry = entry->next;
+	}
+	read_unlock_bh(&client->ingress_lock);
 }
 
-static eg_cache_entry *eg_cache_search_by_cache_id(uint32_t cache_id,
-						  struct mpoa_client *client)
+static void in_destroy_cache(struct mpoa_client *mpc)
 {
-        eg_cache_entry *entry;
-        unsigned long flags;
-
-        read_lock_irqsave(&client->egress_lock, flags);
-        entry = client->eg_cache;
-        while(entry != NULL){
-                if( entry->ctrl_info.cache_id == cache_id){
-                        read_unlock_irqrestore(&client->egress_lock, flags);
-                        return entry;
-                }
-                entry = entry->next;
-        }
-	read_unlock_irqrestore(&client->egress_lock, flags);
+	write_lock_irq(&mpc->ingress_lock);
+	while(mpc->in_cache != NULL)
+		mpc->in_ops->remove_entry(mpc->in_cache, mpc);
+	write_unlock_irq(&mpc->ingress_lock);
 
-        return NULL;
+	return;
 }
 
-static eg_cache_entry *eg_cache_search_by_tag(uint32_t tag,
-					      struct mpoa_client *client)
+static eg_cache_entry *eg_cache_get_by_cache_id(uint32_t cache_id, struct mpoa_client *mpc)
 {
-        unsigned long flags;
-        eg_cache_entry *entry;
+	eg_cache_entry *entry;
 
-        read_lock_irqsave(&client->egress_lock, flags);
-        entry = client->eg_cache;
-        while(entry != NULL){
-                if( entry->ctrl_info.tag == tag){
-                        read_unlock_irqrestore(&client->egress_lock, flags);
-                        return entry;
-                }
-                entry = entry->next;
-        }
-	read_unlock_irqrestore(&client->egress_lock, flags);
+	read_lock_irq(&mpc->egress_lock);
+	entry = mpc->eg_cache;
+	while(entry != NULL){
+		if(entry->ctrl_info.cache_id == cache_id){
+			atomic_inc(&entry->use);
+			read_unlock_irq(&mpc->egress_lock);
+			return entry;
+		}
+		entry = entry->next;
+	}
+	read_unlock_irq(&mpc->egress_lock);
 
-        return NULL;
+	return NULL;
 }
 
-static eg_cache_entry *eg_cache_search_by_vcc(struct atm_vcc *vcc,
-                                               struct mpoa_client *client )
+/* This can be called from any context since it saves CPU flags */
+static eg_cache_entry *eg_cache_get_by_tag(uint32_t tag, struct mpoa_client *mpc)
 {
-        unsigned long flags;
-        eg_cache_entry *entry;
+	unsigned long flags;
+	eg_cache_entry *entry;
 
-        read_lock_irqsave(&client->egress_lock, flags);
-        entry = client->eg_cache;
-        while( entry != NULL ){
-                if( entry->shortcut == vcc ) {
-               	        read_unlock_irqrestore(&client->egress_lock, flags);
-                        return entry;
+	read_lock_irqsave(&mpc->egress_lock, flags);
+	entry = mpc->eg_cache;
+	while (entry != NULL){
+		if (entry->ctrl_info.tag == tag) {
+			atomic_inc(&entry->use);
+			read_unlock_irqrestore(&mpc->egress_lock, flags);
+			return entry;
 		}
-                entry = entry->next;
-        }
-	read_unlock_irqrestore(&client->egress_lock, flags);
+		entry = entry->next;
+	}
+	read_unlock_irqrestore(&mpc->egress_lock, flags);
 
-        return NULL;
+	return NULL;
 }
 
-static eg_cache_entry *eg_cache_search_by_src_ip(uint32_t ipaddr,
-						 struct mpoa_client *client)
+/* This can be called from any context since it saves CPU flags */
+static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc, struct mpoa_client *mpc)
 {
-        unsigned long flags;
-        eg_cache_entry *entry;
+	unsigned long flags;
+	eg_cache_entry *entry;
 
-        read_lock_irqsave(&client->egress_lock, flags);
-        entry = client->eg_cache;
-        while( entry != NULL ){
-                if(entry->latest_ip_addr == ipaddr) {
-                        break;
+	read_lock_irqsave(&mpc->egress_lock, flags);
+	entry = mpc->eg_cache;
+	while (entry != NULL){
+		if (entry->shortcut == vcc) {
+			atomic_inc(&entry->use);
+	       		read_unlock_irqrestore(&mpc->egress_lock, flags);
+			return entry;
 		}
-                entry = entry->next;
-        }
-	read_unlock_irqrestore(&client->egress_lock, flags);
+		entry = entry->next;
+	}
+	read_unlock_irqrestore(&mpc->egress_lock, flags);
 
-        return entry;
+	return NULL;
 }
 
-/*
- * If there are no more references to vcc in ingress cache,
- * we are ready to close it.
- */
-static void close_unused_ingress_vcc(struct atm_vcc *vcc, struct mpoa_client *mpc)
+static eg_cache_entry *eg_cache_get_by_src_ip(uint32_t ipaddr, struct mpoa_client *mpc)
 {
-	if (vcc == NULL)
-		return;
+	eg_cache_entry *entry;
 
-	dprintk("mpoa: mpoa_caches.c: close_unused_ingress_vcc:\n");
-        if (mpc->in_ops->search_by_vcc(vcc, mpc) != NULL)
-                return;                             /* entry still in use */
+	read_lock_irq(&mpc->egress_lock);
+	entry = mpc->eg_cache;
+	while(entry != NULL){
+		if(entry->latest_ip_addr == ipaddr) {
+			atomic_inc(&entry->use);
+	       		read_unlock_irq(&mpc->egress_lock);
+			return entry;
+		}
+		entry = entry->next;
+	}
+	read_unlock_irq(&mpc->egress_lock);
 
-	atm_async_release_vcc(vcc, -EPIPE); /* nobody uses this VCC anymore, close it */
-	dprintk("mpoa: mpoa_caches.c: close_unused_ingress_vcc:, closed one\n");
+	return NULL;
+}
+
+static void eg_cache_put(eg_cache_entry *entry)
+{
+	if (atomic_dec_and_test(&entry->use)) {
+		memset(entry, 0, sizeof(eg_cache_entry));
+		kfree(entry);
+	}
 
 	return;
 }
+
 /*
  * This should be called with write lock on
  */
-static int eg_cache_remove(eg_cache_entry *entry, 
-                           struct mpoa_client *client)
+static void eg_cache_remove_entry(eg_cache_entry *entry,
+				  struct mpoa_client *client)
 {
 	struct atm_vcc *vcc;
-        struct k_message msg; 
-        if(entry == NULL)
-                return 0;
+	struct k_message msg;
 
 	vcc = entry->shortcut;
-        dprintk("mpoa: mpoa_caches.c: removing an egress entry.\n");
-        if (entry->prev != NULL)
-                entry->prev->next = entry->next;
-        else
-                client->eg_cache = entry->next;
-        if (entry->next != NULL)
-                entry->next->prev = entry->prev;
-        memset(entry, 0, sizeof(eg_cache_entry));
-        kfree(entry);
+	dprintk("mpoa: mpoa_caches.c: removing an egress entry.\n");
+	if (entry->prev != NULL)
+		entry->prev->next = entry->next;
+	else
+		client->eg_cache = entry->next;
+	if (entry->next != NULL)
+		entry->next->prev = entry->prev;
+	client->eg_ops->put(entry);
 	if(client->in_cache == NULL && client->eg_cache == NULL){
-	        msg.type = STOP_KEEP_ALIVE_SM;
+		msg.type = STOP_KEEP_ALIVE_SM;
 		msg_to_mpoad(&msg,client);
 	}
 
-	close_unused_ingress_vcc(vcc, client);
+	/* Check if the ingress side still uses this VCC */
+	if (vcc != NULL) {
+		in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client);
+		if (in_entry != NULL) {
+			client->in_ops->put(in_entry);
+			return;
+		}
+		atm_async_release_vcc(vcc, -EPIPE);
+	}
 
-        return 1;
-} 
+	return;
+}
 
-static eg_cache_entry *new_eg_cache_entry(struct k_message *msg, struct mpoa_client *client)
+static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, struct mpoa_client *client)
 {
-        unsigned long flags;
-        unsigned char *ip;
-        eg_cache_entry *entry = kmalloc(sizeof(eg_cache_entry), GFP_KERNEL);
-
-        if (entry == NULL) {
-                printk("mpoa: mpoa_caches.c: new_eg_cache_entry: out of memory\n");
-                return NULL;
-	}
-
-        ip = (unsigned char *)&msg->content.eg_info.eg_dst_ip;
-        dprintk("mpoa: mpoa_caches.c: adding an egress entry, ip = %d.%d.%d.%d, this should be our IP\n", ip[0], ip[1], ip[2], ip[3]);
-        memset(entry, 0, sizeof(eg_cache_entry));
-
-        dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: about to lock\n");
-        write_lock_irqsave(&client->egress_lock, flags);
-        entry->next = client->eg_cache;
-        entry->prev = NULL;
-        if (client->eg_cache != NULL)
-                client->eg_cache->prev = entry;
-        client->eg_cache = entry;
-        write_unlock_irqrestore(&client->egress_lock, flags);
-        dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: unlocked\n");
-
-        memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
-        entry->ctrl_info = msg->content.eg_info;
-        do_gettimeofday(&(entry->tv));
-        entry->entry_state = EGRESS_RESOLVED;
-        dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry cache_id %lu\n", ntohl(entry->ctrl_info.cache_id));
-        ip = (unsigned char *)&entry->ctrl_info.mps_ip;
-        dprintk("mpoa: mpoa_caches.c: mps_ip = %d.%d.%d.%d\n", ip[0], ip[1], ip[2], ip[3]);
-        return entry;
+	unsigned char *ip;
+	eg_cache_entry *entry = kmalloc(sizeof(eg_cache_entry), GFP_KERNEL);
+
+	if (entry == NULL) {
+		printk("mpoa: mpoa_caches.c: new_eg_cache_entry: out of memory\n");
+		return NULL;
+	}
+
+	ip = (unsigned char *)&msg->content.eg_info.eg_dst_ip;
+	dprintk("mpoa: mpoa_caches.c: adding an egress entry, ip = %u.%u.%u.%u, this should be our IP\n", NIPQUAD(ip));
+	memset(entry, 0, sizeof(eg_cache_entry));
+
+	atomic_set(&entry->use, 1);
+	dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: about to lock\n");
+	write_lock_irq(&client->egress_lock);
+	entry->next = client->eg_cache;
+	entry->prev = NULL;
+	if (client->eg_cache != NULL)
+		client->eg_cache->prev = entry;
+	client->eg_cache = entry;
+
+	memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
+	entry->ctrl_info = msg->content.eg_info;
+	do_gettimeofday(&(entry->tv));
+	entry->entry_state = EGRESS_RESOLVED;
+	dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry cache_id %lu\n", ntohl(entry->ctrl_info.cache_id));
+	ip = (unsigned char *)&entry->ctrl_info.mps_ip;
+	dprintk("mpoa: mpoa_caches.c: mps_ip = %u.%u.%u.%u\n", NIPQUAD(ip));
+	atomic_inc(&entry->use);
+
+	write_unlock_irq(&client->egress_lock);
+	dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: unlocked\n");
+
+	return entry;
 }
 
 static void update_eg_cache_entry(eg_cache_entry * entry, uint16_t holding_time)
 {
-        do_gettimeofday(&(entry->tv));
-        entry->entry_state = EGRESS_RESOLVED;
-        entry->ctrl_info.holding_time = holding_time;
+	do_gettimeofday(&(entry->tv));
+	entry->entry_state = EGRESS_RESOLVED;
+	entry->ctrl_info.holding_time = holding_time;
 
-        return;
+	return;
 }
 
-static void clear_expired(struct mpoa_client *client){
-        eg_cache_entry *entry, *next_entry;
-        unsigned long flags;
-        struct timeval now;
+static void clear_expired(struct mpoa_client *client)
+{
+	eg_cache_entry *entry, *next_entry;
+	struct timeval now;
 	struct k_message msg;
 
-        do_gettimeofday(&now);
+	do_gettimeofday(&now);
 
-        write_lock_irqsave(&client->egress_lock, flags);
-        entry = client->eg_cache;
-        while(entry != NULL){
-	        next_entry = entry->next;
-                if((now.tv_sec - entry->tv.tv_sec) 
-                   > entry->ctrl_info.holding_time){
-		        msg.type = SND_EGRESS_PURGE;
+	write_lock_irq(&client->egress_lock);
+	entry = client->eg_cache;
+	while(entry != NULL){
+		next_entry = entry->next;
+		if((now.tv_sec - entry->tv.tv_sec)
+		   > entry->ctrl_info.holding_time){
+			msg.type = SND_EGRESS_PURGE;
 			msg.content.eg_info = entry->ctrl_info;
-		        dprintk("mpoa: mpoa_caches.c: egress_cache: holding time expired, cache_id = %lu.\n",ntohl(entry->ctrl_info.cache_id));
+			dprintk("mpoa: mpoa_caches.c: egress_cache: holding time expired, cache_id = %lu.\n",ntohl(entry->ctrl_info.cache_id));
 			msg_to_mpoad(&msg, client);
-                        eg_cache_remove(entry, client);
-                }
-                entry = next_entry;
-        }
-        write_unlock_irqrestore(&client->egress_lock, flags);
+			client->eg_ops->remove_entry(entry, client);
+		}
+		entry = next_entry;
+	}
+	write_unlock_irq(&client->egress_lock);
+
+	return;
+}
+
+static void eg_destroy_cache(struct mpoa_client *mpc)
+{
+	write_lock_irq(&mpc->egress_lock);
+	while(mpc->eg_cache != NULL)
+		mpc->eg_ops->remove_entry(mpc->eg_cache, mpc);
+	write_unlock_irq(&mpc->egress_lock);
 
-        return;
+	return;
 }
 
 
 
 static struct in_cache_ops ingress_ops = {
-        new_in_cache_entry,               /* new_entry        */
-        in_cache_search,                  /* search           */
-        in_cache_search_with_mask,        /* search_with_mask */
-	in_cache_search_by_vcc,           /* search_by_vcc    */
-        cache_hit,                        /* cache_hit        */
-        in_cache_remove,                  /* cache_remove     */
-        clear_count_and_expired,          /* clear_count      */
-        check_resolving_entries,          /* check_resolving  */
-        refresh_entries,                  /* refresh          */
+	in_cache_add_entry,               /* add_entry       */
+	in_cache_get,                     /* get             */
+	in_cache_get_with_mask,           /* get_with_mask   */
+	in_cache_get_by_vcc,              /* get_by_vcc      */
+	in_cache_put,                     /* put             */
+	in_cache_remove_entry,            /* remove_entry    */
+	cache_hit,                        /* cache_hit       */
+	clear_count_and_expired,          /* clear_count     */
+	check_resolving_entries,          /* check_resolving */
+	refresh_entries,                  /* refresh         */
+	in_destroy_cache                  /* destroy_cache   */
 };
 
 static struct eg_cache_ops egress_ops = {
-        new_eg_cache_entry,               /* new_entry          */
-        eg_cache_search_by_cache_id,      /* search_by_cache_id */
-        eg_cache_search_by_tag,           /* search_by_tag      */ 
-        eg_cache_search_by_vcc,           /* search_by_vcc      */
-        eg_cache_search_by_src_ip,        /* search_by_src_ip   */
-        eg_cache_remove,                  /* cache_remove       */
-        update_eg_cache_entry,            /* update             */
-	clear_expired                     /* clear_expired      */
+	eg_cache_add_entry,               /* add_entry        */
+	eg_cache_get_by_cache_id,         /* get_by_cache_id  */
+	eg_cache_get_by_tag,              /* get_by_tag       */
+	eg_cache_get_by_vcc,              /* get_by_vcc       */
+	eg_cache_get_by_src_ip,           /* get_by_src_ip    */
+	eg_cache_put,                     /* put              */
+	eg_cache_remove_entry,            /* remove_entry     */
+	update_eg_cache_entry,            /* update           */
+	clear_expired,                    /* clear_expired    */
+	eg_destroy_cache                  /* destroy_cache    */
 };
 
 
 void atm_mpoa_init_cache(struct mpoa_client *mpc)
 {
-        mpc->in_ops = &ingress_ops;
-        mpc->eg_ops = &egress_ops;
+	mpc->in_ops = &ingress_ops;
+	mpc->eg_ops = &egress_ops;
 
-        return;
+	return;
 }