code review and fix the old race condition in dev->set_multicast_list

please test.

1 files changed, 257 insertions, 240 deletions

diff --git a/linux/drivers/media/dvb/dvb-core/dvb_net.c b/linux/drivers/media/dvb/dvb-core/dvb_net.c
index a98258794..529ba27b5 100644
--- a/linux/drivers/media/dvb/dvb-core/dvb_net.c
+++ b/linux/drivers/media/dvb/dvb-core/dvb_net.c
@@ -2,7 +2,7 @@
  * dvb_net.c
  *
  * Copyright (C) 2001 Convergence integrated media GmbH
- *                    Ralph Metzler <ralph@convergence.de>
+ *		    Ralph Metzler <ralph@convergence.de>
  * Copyright (C) 2002 Ralph Metzler <rjkm@metzlerbros.de>
  *
  * This program is free software; you can redistribute it and/or
@@ -25,34 +25,31 @@
  */
 
 #include <asm/uaccess.h>
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/string.h>
-#include <linux/ioctl.h>
-#include <linux/slab.h>
 
 #include <linux/dvb/net.h>
-
 #include "dvb_demux.h"
 #include "dvb_net.h"
 #include "dvb_functions.h"
 
+
 #define DVB_NET_MULTICAST_MAX 10
 
 struct dvb_net_priv {
-        struct net_device_stats stats;
-        char name[6];
+	struct net_device_stats stats;
+	char name[6];
 	u16 pid;
-        struct dmx_demux *demux;
+	struct dmx_demux *demux;
 	struct dmx_section_feed *secfeed;
 	struct dmx_section_filter *secfilter;
 	int multi_num;
 	struct dmx_section_filter *multi_secfilter[DVB_NET_MULTICAST_MAX];
 	unsigned char multi_macs[DVB_NET_MULTICAST_MAX][6];
 	int mode;
+	struct tq_struct tq;
 };
 
-/*
+
+/**
  *	Determine the packet's protocol ID. The rule here is that we 
  *	assume 802.3 if the type field is short enough to be a length.
  *	This is normal practice and works for any 'now in use' protocol.
@@ -60,8 +57,9 @@ struct dvb_net_priv {
  *  stolen from eth.c out of the linux kernel, hacked for dvb-device
  *  by Michael Holzt <kju@debian.org>
  */
- 
-unsigned short my_eth_type_trans(struct sk_buff *skb, struct net_device *dev)
+static 
+unsigned short dvb_net_eth_type_trans(struct sk_buff *skb,
+				      struct net_device *dev)
 {
 	struct ethhdr *eth;
 	unsigned char *rawp;
@@ -70,20 +68,19 @@ unsigned short my_eth_type_trans(struct sk_buff *skb, struct net_device *dev)
 	skb_pull(skb,dev->hard_header_len);
 	eth= skb->mac.ethernet;
 	
-	if(*eth->h_dest&1)
-	{
-		if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
-			skb->pkt_type=PACKET_BROADCAST;
+	if(*eth->h_dest & 1) {
+		if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN) == 0)
+			skb->pkt_type = PACKET_BROADCAST;
 		else
-			skb->pkt_type=PACKET_MULTICAST;
+			skb->pkt_type = PACKET_MULTICAST;
 	}
-	
+
 	if (ntohs(eth->h_proto) >= 1536)
 		return eth->h_proto;
-		
+
 	rawp = skb->data;
-	
-	/*
+
+	/**
 	 *	This is a magic hack to spot IPX packets. Older Novell breaks
 	 *	the protocol design and runs IPX over 802.3 without an 802.2 LLC
 	 *	layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
@@ -92,84 +89,94 @@ unsigned short my_eth_type_trans(struct sk_buff *skb, struct net_device *dev)
 	if (*(unsigned short *)rawp == 0xFFFF)
 		return htons(ETH_P_802_3);
 		
-	/*
+	/**
 	 *	Real 802.2 LLC
 	 */
 	return htons(ETH_P_802_2);
 }
 
-static void 
-dvb_net_sec(struct net_device *dev, const u8 *pkt, int pkt_len)
+
+static 
+void dvb_net_sec(struct net_device *dev, u8 *pkt, int pkt_len)
 {
-        u8 *eth;
-        struct sk_buff *skb;
+	u8 *eth;
+	struct sk_buff *skb;
+
+	if (pkt_len < 13) {
+		printk("%s: IP/MPE packet length = %d too small.\n",
+			dev->name, pkt_len);
+		return;
+	}
 
-        if (pkt_len<13) {
-                printk("%s: IP/MPE packet length = %d too small.\n", dev->name, pkt_len);
+	if (!(skb = dev_alloc_skb(pkt_len+2))) {
+		printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
+		       dev->name);
+		((struct dvb_net_priv *)dev->priv)->stats.rx_dropped++;
 		return;
 	}
-        skb = dev_alloc_skb(pkt_len+2);
-        if (skb == NULL) {
-                printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
-                       dev->name);
-                ((struct dvb_net_priv *)dev->priv)->stats.rx_dropped++;
-                return;
-        }
-        eth=(u8 *) skb_put(skb, pkt_len+2);
-        memcpy(eth+14, (void*)pkt+12, pkt_len-12);
-
-        eth[0]=pkt[0x0b];
-        eth[1]=pkt[0x0a];
-        eth[2]=pkt[0x09];
-        eth[3]=pkt[0x08];
-        eth[4]=pkt[0x04];
-        eth[5]=pkt[0x03];
-        eth[6]=eth[7]=eth[8]=eth[9]=eth[10]=eth[11]=0;
-        eth[12]=0x08; eth[13]=0x00;
-
-	skb->protocol=my_eth_type_trans(skb,dev);
-        skb->dev=dev;
-        
-        ((struct dvb_net_priv *)dev->priv)->stats.rx_packets++;
-        ((struct dvb_net_priv *)dev->priv)->stats.rx_bytes+=skb->len;
-        netif_rx(skb);
+
+	eth=(u8 *) skb_put(skb, pkt_len+2);
+	memcpy(eth+14, (void*)pkt+12, pkt_len-12);
+
+	eth[0] = pkt[0x0b];
+	eth[1] = pkt[0x0a];
+	eth[2] = pkt[0x09];
+	eth[3] = pkt[0x08];
+	eth[4] = pkt[0x04];
+	eth[5] = pkt[0x03];
+	eth[6] = eth[7] = eth[8] = eth[9] = eth[10] = eth[11] = 0;
+	eth[12] = 0x08;
+	eth[13] = 0x00;
+
+	skb->protocol = dvb_net_eth_type_trans(skb,dev);
+	skb->dev = dev;
+
+	((struct dvb_net_priv *)dev->priv)->stats.rx_packets++;
+	((struct dvb_net_priv *)dev->priv)->stats.rx_bytes += skb->len;
+	netif_rx(skb);
 }
  
-static int 
-dvb_net_callback(const u8 *buffer1, size_t buffer1_len,
-		 const u8 *buffer2, size_t buffer2_len,
-		 struct dmx_section_filter *filter,
-		 enum dmx_success success)
+static
+int dvb_net_callback (const u8 *buffer1, size_t buffer1_len,
+		      const u8 *buffer2, size_t buffer2_len,
+		      struct dmx_section_filter *filter,
+		      enum dmx_success success)
 {
-        struct net_device *dev=(struct net_device *) filter->priv;
+	struct net_device *dev=(struct net_device *) filter->priv;
 
-	/* FIXME: this only works if exactly one complete section is
-	          delivered in buffer1 only */
-	dvb_net_sec(dev, buffer1, buffer1_len);
+	/**
+	 * we rely on the DVB API definition where exactly one complete 
+	 * section is delivered in buffer1
+	 */
+	dvb_net_sec (dev, (u8*) buffer1, buffer1_len);
 	return 0;
 }
 
-static int
-dvb_net_tx(struct sk_buff *skb, struct net_device *dev)
+
+static
+int dvb_net_tx (struct sk_buff *skb, struct net_device *dev)
 {
 	return 0;
 }
 
-static u8 mask_normal[6]={0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
-static u8 mask_allmulti[6]={0xff, 0xff, 0xff, 0x00, 0x00, 0x00};
-static u8 mac_allmulti[6]={0x01, 0x00, 0x5e, 0x00, 0x00, 0x00};
-static u8 mask_promisc[6]={0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
 
-static int 
-dvb_net_filter_set(struct net_device *dev, 
-		   struct dmx_section_filter **secfilter,
-		   u8 *mac, u8 *mac_mask)
+static u8 mask_normal   [6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+static u8 mask_allmulti [6] = {0xff, 0xff, 0xff, 0x00, 0x00, 0x00};
+static u8 mac_allmulti  [6] = {0x01, 0x00, 0x5e, 0x00, 0x00, 0x00};
+static u8 mask_promisc  [6] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
+
+static
+int dvb_net_filter_set (struct net_device *dev,
+			struct dmx_section_filter **secfilter,
+			u8 *mac, u8 *mac_mask)
 {
 	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
 	int ret;
 
 	*secfilter=0;
+
 	ret = priv->secfeed->allocate_filter(priv->secfeed, secfilter);
+	
 	if (ret<0) {
 		printk("%s: could not get filter\n", dev->name);
 		return ret;
@@ -181,58 +188,56 @@ dvb_net_filter_set(struct net_device *dev,
 	memset((*secfilter)->filter_mask,  0x00, DMX_MAX_FILTER_SIZE);
 	memset((*secfilter)->filter_mode,  0xff, DMX_MAX_FILTER_SIZE);
 
-	(*secfilter)->filter_value[0]=0x3e;
-	(*secfilter)->filter_mask[0]=0xff;
-
-	(*secfilter)->filter_value[3]=mac[5];
-	(*secfilter)->filter_mask[3]=mac_mask[5];
-	(*secfilter)->filter_value[4]=mac[4];
-	(*secfilter)->filter_mask[4]=mac_mask[4];
-	(*secfilter)->filter_value[8]=mac[3];
-	(*secfilter)->filter_mask[8]=mac_mask[3];
-	(*secfilter)->filter_value[9]=mac[2];
-	(*secfilter)->filter_mask[9]=mac_mask[2];
-
-	(*secfilter)->filter_value[10]=mac[1];
-	(*secfilter)->filter_mask[10]=mac_mask[1];
-	(*secfilter)->filter_value[11]=mac[0];
-	(*secfilter)->filter_mask[11]=mac_mask[0];
+	(*secfilter)->filter_value[0] = 0x3e;
+	(*secfilter)->filter_value[3] = mac[5];
+	(*secfilter)->filter_value[4] = mac[4];
+	(*secfilter)->filter_value[8] = mac[3];
+	(*secfilter)->filter_value[9] = mac[2];
+	(*secfilter)->filter_value[10] = mac[1];
+	(*secfilter)->filter_value[11] = mac[0];
+
+	(*secfilter)->filter_mask[0] = 0xff;
+	(*secfilter)->filter_mask[3] = mac_mask[5];
+	(*secfilter)->filter_mask[4] = mac_mask[4];
+	(*secfilter)->filter_mask[8] = mac_mask[3];
+	(*secfilter)->filter_mask[9] = mac_mask[2];
+	(*secfilter)->filter_mask[10] = mac_mask[1];
+	(*secfilter)->filter_mask[11] = mac_mask[0];
 
 	printk("%s: filter mac=%02x %02x %02x %02x %02x %02x\n", 
 	       dev->name, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+
 	return 0;
 }
 
-static int
-dvb_net_feed_start(struct net_device *dev)
+static
+int dvb_net_feed_start (struct net_device *dev)
 {
 	int ret, i;
 	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
-        struct dmx_demux *demux = priv->demux;
-        unsigned char *mac = (unsigned char *) dev->dev_addr;
+	struct dmx_demux *demux = priv->demux;
+	unsigned char *mac = (unsigned char *) dev->dev_addr;
 		
-	priv->secfeed=0;
-	priv->secfilter=0;
+	priv->secfeed = 0;
+	priv->secfilter = 0;
 
 	ret=demux->allocate_section_feed(demux, &priv->secfeed, 
 					 dvb_net_callback);
-	if (ret<0) {
+	if (ret < 0) {
 		printk("%s: could not get section feed\n", dev->name);
 		return ret;
 	}
 
-	ret=priv->secfeed->set(priv->secfeed, priv->pid, 32768, 0, 0);
-	if (ret<0) {
+	ret = priv->secfeed->set(priv->secfeed, priv->pid, 32768, 0, 0);
+
+	if (ret < 0) {
 		printk("%s: could not set section feed\n", dev->name);
-		priv->demux->
-		        release_section_feed(priv->demux, priv->secfeed);
+		priv->demux->release_section_feed(priv->demux, priv->secfeed);
 		priv->secfeed=0;
 		return ret;
 	}
-	/* fixme: is this correct? */
-	try_module_get(THIS_MODULE);
 
-	if (priv->mode<3) 
+	if (priv->mode < 3) 
 		dvb_net_filter_set(dev, &priv->secfilter, mac, mask_normal);
 
 	switch (priv->mode) {
@@ -242,157 +247,160 @@ dvb_net_feed_start(struct net_device *dev)
 					   priv->multi_macs[i], mask_normal);
 		break;
 	case 2:
-		priv->multi_num=1;
-		dvb_net_filter_set(dev, &priv->multi_secfilter[0], mac_allmulti, mask_allmulti);
+		priv->multi_num = 1;
+		dvb_net_filter_set(dev, &priv->multi_secfilter[0],
+				   mac_allmulti, mask_allmulti);
 		break;
 	case 3:
-		priv->multi_num=0;
+		priv->multi_num = 0;
 		dvb_net_filter_set(dev, &priv->secfilter, mac, mask_promisc);
 		break;
 	}
-	
+
 	priv->secfeed->start_filtering(priv->secfeed);
 	return 0;
 }
 
-static void
-dvb_net_feed_stop(struct net_device *dev)
+
+static
+void dvb_net_feed_stop (struct net_device *dev)
 {
 	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
 	int i;
 
-        if (priv->secfeed) {
-	        if (priv->secfeed->is_filtering)
-		        priv->secfeed->stop_filtering(priv->secfeed);
-	        if (priv->secfilter)
-		        priv->secfeed->
-			        release_filter(priv->secfeed, 
-					       priv->secfilter);
-		priv->secfilter=0;
+	if (priv->secfeed) {
+		if (priv->secfeed->is_filtering)
+			priv->secfeed->stop_filtering(priv->secfeed);
+
+		if (priv->secfilter)
+			priv->secfeed->release_filter(priv->secfeed,
+						      priv->secfilter);
+		priv->secfilter = 0;
 
 		for (i=0; i<priv->multi_num; i++) {
 			if (priv->multi_secfilter[i])
-				priv->secfeed->
-					release_filter(priv->secfeed, 
-						       priv->multi_secfilter[i]);
+				priv->secfeed->release_filter(priv->secfeed, 
+						     priv->multi_secfilter[i]);
 			priv->multi_secfilter[i]=0;
 		}
-		priv->demux->
-		        release_section_feed(priv->demux, priv->secfeed);
+
+		priv->demux->release_section_feed(priv->demux, priv->secfeed);
 		priv->secfeed=0;
-		/* fixme: is this correct? */
-		module_put(THIS_MODULE);
 	} else
 		printk("%s: no feed to stop\n", dev->name);
 }
 
-static int
-dvb_add_mc_filter(struct net_device *dev, struct dev_mc_list *mc)
+
+static
+int dvb_set_mc_filter (struct net_device *dev, struct dev_mc_list *mc)
 {
 	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
-	int ret;
 
-	if (priv->multi_num >= DVB_NET_MULTICAST_MAX)
+	if (priv->multi_num==DVB_NET_MULTICAST_MAX)
 		return -ENOMEM;
 
-	ret = memcmp(priv->multi_macs[priv->multi_num], mc->dmi_addr, 6);
 	memcpy(priv->multi_macs[priv->multi_num], mc->dmi_addr, 6);
 
 	priv->multi_num++;
-
-	return ret;
+	return 0;
 }
 
-static void
-dvb_net_set_multi(struct net_device *dev)
+
+static
+void tq_set_multicast_list (void *data)
 {
+	struct net_device *dev = data;
 	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
-	struct dev_mc_list *mc;
-	int mci;
-	int update = 0;
-	
-	if(dev->flags & IFF_PROMISC) {
-//	printk("%s: promiscuous mode\n", dev->name);
-		if(priv->mode != 3)
-			update = 1;
+
+	dvb_net_feed_stop(dev);
+
+	priv->mode = 0;
+
+	if (dev->flags & IFF_PROMISC) {
+		printk("%s: promiscuous mode\n", dev->name);
 		priv->mode = 3;
-	} else if(dev->flags & IFF_ALLMULTI) {
-//	printk("%s: allmulti mode\n", dev->name);
-		if(priv->mode != 2)
-			update = 1;
+	} else if((dev->flags & IFF_ALLMULTI)) {
+		printk("%s: allmulti mode\n", dev->name);
 		priv->mode = 2;
-	} else if(dev->mc_count > 0) {
-//	printk("%s: set_mc_list, %d entries\n", 
-//	       dev->name, dev->mc_count);
-		if(priv->mode != 1)
-			update = 1;
+	} else if(dev->mc_count) {
+		int mci;
+		struct dev_mc_list *mc;
+
+		printk("%s: set_mc_list, %d entries\n", 
+		       dev->name, dev->mc_count);
+
 		priv->mode = 1;
 		priv->multi_num = 0;
-		for (mci = 0, mc=dev->mc_list; 
-		     mci < dev->mc_count;
-		     mc=mc->next, mci++)
-			if(dvb_add_mc_filter(dev, mc) != 0)
-				update = 1;
-	} else {
-		if(priv->mode != 0)
-			update = 1;
-		priv->mode = 0;
-	}
 
-	if(netif_running(dev) != 0 && update > 0)
-	{
-		dvb_net_feed_stop(dev);
-		dvb_net_feed_start(dev);
+		for (mci=0, mc=dev->mc_list; 
+		     mci<dev->mc_count;
+		     mc=mc->next, mci++) {
+			dvb_set_mc_filter(dev, mc);
+		} 
 	}
+
+	dvb_net_feed_start(dev);
 }
 
-static int
-dvb_net_set_config(struct net_device *dev, struct ifmap *map)
+	
+static
+void dvb_net_set_multicast_list (struct net_device *dev)
+{
+	struct dvb_net_priv *priv = (struct dvb_net_priv*) dev->priv;
+	queue_task(&priv->tq, &tq_immediate);
+}
+
+
+static
+int dvb_net_set_config (struct net_device *dev, struct ifmap *map)
 {
 	if (netif_running(dev))
 		return -EBUSY;
 	return 0;
 }
 
-static int
-dvb_net_set_mac(struct net_device *dev, void *p)
+
+static
+int dvb_net_set_mac (struct net_device *dev, void *p)
 {
 	struct sockaddr *addr=p;
-	int update;
 
-	update = memcmp(dev->dev_addr, addr->sa_data, dev->addr_len);
 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
-	if (netif_running(dev) != 0 && update > 0) {
+
+	if (netif_running(dev)) {
 		dvb_net_feed_stop(dev);
 		dvb_net_feed_start(dev);
 	}
+
 	return 0;
 }
 
 
-static int
-dvb_net_open(struct net_device *dev)
+static
+int dvb_net_open (struct net_device *dev)
 {
 	dvb_net_feed_start(dev);
 	return 0;
 }
 
-static int
-dvb_net_stop(struct net_device *dev)
+
+static
+int dvb_net_stop (struct net_device *dev)
 {
-        dvb_net_feed_stop(dev);
+	dvb_net_feed_stop(dev);
 	return 0;
 }
 
-static struct net_device_stats *
-dvb_net_get_stats(struct net_device *dev)
+
+static
+struct net_device_stats* dvb_net_get_stats (struct net_device *dev)
 {
-        return &((struct dvb_net_priv*) dev->priv)->stats;
+	return &((struct dvb_net_priv*) dev->priv)->stats;
 }
 
 
-static int
-dvb_net_init_dev(struct net_device *dev)
+static
+int dvb_net_init_dev (struct net_device *dev)
 {
 	ether_setup(dev);
 
@@ -400,39 +408,40 @@ dvb_net_init_dev(struct net_device *dev)
 	dev->stop		= dvb_net_stop;
 	dev->hard_start_xmit	= dvb_net_tx;
 	dev->get_stats		= dvb_net_get_stats;
-	dev->set_multicast_list = dvb_net_set_multi;
-	dev->set_config         = dvb_net_set_config;
+	dev->set_multicast_list = dvb_net_set_multicast_list;
+	dev->set_config	 	= dvb_net_set_config;
 	dev->set_mac_address    = dvb_net_set_mac;
 	dev->mtu		= 4096;
-	dev->mc_count           = 0;
-
-	dev->flags             |= IFF_NOARP;
+	dev->mc_count		= 0;
 	dev->hard_header_cache  = NULL;
 
-	//SET_MODULE_OWNER(dev);
-	
+	dev->flags |= IFF_NOARP;
+
 	return 0;
 }
 
-static int 
-get_if(struct dvb_net *dvbnet)
+
+static
+int get_if (struct dvb_net *dvbnet)
 {
 	int i;
 
 	for (i=0; i<dvbnet->dev_num; i++) 
 		if (!dvbnet->state[i])
 			break;
-	if (i==dvbnet->dev_num)
+
+	if (i == dvbnet->dev_num)
 		return -1;
-	dvbnet->state[i]=1;
+	
+	dvbnet->state[i] = 1;
 	return i;
 }
 
 
-int 
-dvb_net_add_if(struct dvb_net *dvbnet, u16 pid)
+static
+int dvb_net_add_if(struct dvb_net *dvbnet, u16 pid)
 {
-        struct net_device *net;
+	struct net_device *net;
 	struct dmx_demux *demux;
 	struct dvb_net_priv *priv;
 	int result;
@@ -449,101 +458,105 @@ dvb_net_add_if(struct dvb_net *dvbnet, u16 pid)
 	net->irq       = 0;
 	net->dma       = 0;
 	net->mem_start = 0;
-        memcpy(net->name, "dvb0_0", 7);
-        net->name[3]=dvbnet->card_num+0x30;
-        net->name[5]=if_num+0x30;
-        net->next      = NULL;
-        net->init      = dvb_net_init_dev;
-        net->priv      = kmalloc(sizeof(struct dvb_net_priv), GFP_KERNEL);
-	if (net->priv == NULL)
-			return -ENOMEM;
+	memcpy(net->name, "dvb0_0", 7);
+	net->name[3]   = dvbnet->card_num+0x30;
+	net->name[5]   = if_num + '0';
+	net->next      = NULL;
+	net->init      = dvb_net_init_dev;
+
+	if (!(net->priv = kmalloc(sizeof(struct dvb_net_priv), GFP_KERNEL)))
+		return -ENOMEM;
 
 	priv = net->priv;
 	memset(priv, 0, sizeof(struct dvb_net_priv));
-        priv->demux = demux;
-        priv->pid = pid;
+	priv->demux = demux;
+	priv->pid = pid;
 	priv->mode = 0;
 
-        net->base_addr = pid;
-                
+	PREPARE_TQUEUE(&priv->tq, tq_set_multicast_list, net);
+
+	net->base_addr = pid;
+
 	if ((result = register_netdev(net)) < 0) {
 		return result;
 	}
-	/* fixme: is this correct? */
-	try_module_get(THIS_MODULE);
 
-        return if_num;
+	return if_num;
 }
 
-int 
-dvb_net_remove_if(struct dvb_net *dvbnet, int num)
+
+static
+int dvb_net_remove_if(struct dvb_net *dvbnet, int num)
 {
 	if (!dvbnet->state[num])
 		return -EINVAL;
 	dvb_net_stop(&dvbnet->device[num]);
-        kfree(dvbnet->device[num].priv);
-        unregister_netdev(&dvbnet->device[num]);
+	kfree(dvbnet->device[num].priv);
+	unregister_netdev(&dvbnet->device[num]);
 	dvbnet->state[num]=0;
-	/* fixme: is this correct? */
-	module_put(THIS_MODULE);
-
 	return 0;
 }
 
+
+static
 int dvb_net_do_ioctl(struct inode *inode, struct file *file, 
 		  unsigned int cmd, void *parg)
 {
 	struct dvb_device *dvbdev = (struct dvb_device *) file->private_data;
 	struct dvb_net *dvbnet = (struct dvb_net *) dvbdev->priv;
 
-	if (((file->f_flags&O_ACCMODE)==O_RDONLY))
+	if (((file->f_flags&O_ACCMODE) == O_RDONLY))
 		return -EPERM;
 	
 	switch (cmd) {
 	case NET_ADD_IF:
 	{
-		struct dvb_net_if *dvbnetif=(struct dvb_net_if *)parg;
+		struct dvb_net_if *dvbnetif = (struct dvb_net_if *)parg;
 		int result;
 		
-		result=dvb_net_add_if(dvbnet, dvbnetif->pid);
+		result = dvb_net_add_if(dvbnet, dvbnetif->pid);
 		if (result<0)
 			return result;
-		dvbnetif->if_num=result;
+		dvbnetif->if_num = result;
 		break;
 	}
 	case NET_GET_IF:
 	{
 		struct net_device *netdev;
 		struct dvb_net_priv *priv_data;
-		struct dvb_net_if *dvbnetif=(struct dvb_net_if *)parg;
+		struct dvb_net_if *dvbnetif = (struct dvb_net_if *)parg;
 
 		if (dvbnetif->if_num >= dvbnet->dev_num ||
 		    !dvbnet->state[dvbnetif->if_num])
 			return -EFAULT;
 
-		netdev=(struct net_device*)&dvbnet->device[dvbnetif->if_num];
-		priv_data=(struct dvb_net_priv*)netdev->priv;
-		dvbnetif->pid=priv_data->pid;
+		netdev = (struct net_device*)&dvbnet->device[dvbnetif->if_num];
+		priv_data = (struct dvb_net_priv*)netdev->priv;
+		dvbnetif->pid = priv_data->pid;
 		break;
 	}
 	case NET_REMOVE_IF:
-		return dvb_net_remove_if(dvbnet, (long) parg);
+		return dvb_net_remove_if(dvbnet, (int) parg);
 	default:
 		return -EINVAL;
 	}
+
 	return 0;
 }
 
-static int 
-dvb_net_ioctl(struct inode *inode, struct file *file,
-	      unsigned int cmd, unsigned long arg)
+
+static
+int dvb_net_ioctl(struct inode *inode, struct file *file,
+		  unsigned int cmd, unsigned long arg)
 {
 	return dvb_usercopy(inode, file, cmd, arg, dvb_net_do_ioctl);
 }
 
-static struct file_operations dvb_net_fops = {
+
+static
+struct file_operations dvb_net_fops = {
 	.owner = THIS_MODULE,
-        .read =	0,
+	.read =	0,
 	.write = 0,
 	.ioctl = dvb_net_ioctl,
 	.open =	dvb_generic_open,
@@ -551,19 +564,22 @@ static struct file_operations dvb_net_fops = {
 	.poll =	0,
 };
 
-static struct dvb_device dvbdev_net = {
-        .priv = 0,
-        .users = 1,
-        .writers = 1,
-        .fops = &dvb_net_fops,
+
+static
+struct dvb_device dvbdev_net = {
+	.priv = 0,
+	.users = 1,
+	.writers = 1,
+	.fops = &dvb_net_fops,
 };
 
-void
-dvb_net_release(struct dvb_net *dvbnet)
+
+void dvb_net_release (struct dvb_net *dvbnet)
 {
 	int i;
 
 	dvb_unregister_device(dvbnet->dvbdev);
+
 	for (i=0; i<dvbnet->dev_num; i++) {
 		if (!dvbnet->state[i])
 			continue;
@@ -571,8 +587,9 @@ dvb_net_release(struct dvb_net *dvbnet)
 	}
 }
 
-int
-dvb_net_init(struct dvb_adapter *adap, struct dvb_net *dvbnet, struct dmx_demux *dmx)
+
+int dvb_net_init (struct dvb_adapter *adap, struct dvb_net *dvbnet,
+		  struct dmx_demux *dmx)
 {
 	int i;