[NET]: Kill skb->list

Remove the "list" member of struct sk_buff, as it is entirely
redundant.  All SKB list removal callers know which list the
SKB is on, so storing this in sk_buff does nothing other than
taking up some space.

Two tricky bits were SCTP, which I took care of, and two ATM
drivers which Francois Romieu <romieu@fr.zoreil.com> fixed
up.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>

drivers/atm/nicstar.h

@@ -103,8 +103,14 @@
 
 #define NS_IOREMAP_SIZE 4096
 
-#define BUF_SM 0x00000000	/* These two are used for push_rxbufs() */
-#define BUF_LG 0x00000001       /* CMD, Write_FreeBufQ, LBUF bit */
+/*
+ * BUF_XX distinguish the Rx buffers depending on their (small/large) size.
+ * BUG_SM and BUG_LG are both used by the driver and the device.
+ * BUF_NONE is only used by the driver.
+ */
+#define BUF_SM		0x00000000	/* These two are used for push_rxbufs() */
+#define BUF_LG		0x00000001	/* CMD, Write_FreeBufQ, LBUF bit */
+#define BUF_NONE 	0xffffffff	/* Software only: */
 
 #define NS_HBUFSIZE 65568	/* Size of max. AAL5 PDU */
 #define NS_MAX_IOVECS (2 + (65568 - NS_SMBUFSIZE) / \
@@ -684,6 +690,12 @@ enum ns_regs
 /* Device driver structures ***************************************************/
 
 
+struct ns_skb_cb {
+	u32 buf_type;			/* BUF_SM/BUF_LG/BUF_NONE */
+};
+
+#define NS_SKB_CB(skb)	((struct ns_skb_cb *)((skb)->cb))
+
 typedef struct tsq_info
 {
    void *org;

drivers/atm/zatm.c

@@ -417,10 +417,12 @@ printk("dummy: 0x%08lx, 0x%08lx\n",dummy[0],dummy[1]);
 		chan = (here[3] & uPD98401_AAL5_CHAN) >>
 		    uPD98401_AAL5_CHAN_SHIFT;
 		if (chan < zatm_dev->chans && zatm_dev->rx_map[chan]) {
+			int pos = ZATM_VCC(vcc)->pool;
+
 			vcc = zatm_dev->rx_map[chan];
-			if (skb == zatm_dev->last_free[ZATM_VCC(vcc)->pool])
-				zatm_dev->last_free[ZATM_VCC(vcc)->pool] = NULL;
-			skb_unlink(skb);
+			if (skb == zatm_dev->last_free[pos])
+				zatm_dev->last_free[pos] = NULL;
+			skb_unlink(skb, zatm_dev->pool + pos);
 		}
 		else {
 			printk(KERN_ERR DEV_LABEL "(itf %d): RX indication "

drivers/bluetooth/bfusb.c

@@ -158,7 +158,7 @@ static int bfusb_send_bulk(struct bfusb *bfusb, struct sk_buff *skb)
 	if (err) {
 		BT_ERR("%s bulk tx submit failed urb %p err %d", 
 					bfusb->hdev->name, urb, err);
-		skb_unlink(skb);
+		skb_unlink(skb, &bfusb->pending_q);
 		usb_free_urb(urb);
 	} else
 		atomic_inc(&bfusb->pending_tx);
@@ -212,7 +212,7 @@ static void bfusb_tx_complete(struct urb *urb, struct pt_regs *regs)
 
 	read_lock(&bfusb->lock);
 
-	skb_unlink(skb);
+	skb_unlink(skb, &bfusb->pending_q);
 	skb_queue_tail(&bfusb->completed_q, skb);
 
 	bfusb_tx_wakeup(bfusb);
@@ -253,7 +253,7 @@ static int bfusb_rx_submit(struct bfusb *bfusb, struct urb *urb)
 	if (err) {
 		BT_ERR("%s bulk rx submit failed urb %p err %d",
 					bfusb->hdev->name, urb, err);
-		skb_unlink(skb);
+		skb_unlink(skb, &bfusb->pending_q);
 		kfree_skb(skb);
 		usb_free_urb(urb);
 	}
@@ -398,7 +398,7 @@ static void bfusb_rx_complete(struct urb *urb, struct pt_regs *regs)
 		buf   += len;
 	}
 
-	skb_unlink(skb);
+	skb_unlink(skb, &bfusb->pending_q);
 	kfree_skb(skb);
 
 	bfusb_rx_submit(bfusb, urb);

drivers/ieee1394/ieee1394_core.c

@@ -681,7 +681,7 @@ static void handle_packet_response(struct hpsb_host *host, int tcode,
                 return;
         }
 
-	__skb_unlink(skb, skb->list);
+	__skb_unlink(skb, &host->pending_packet_queue);
 
 	if (packet->state == hpsb_queued) {
 		packet->sendtime = jiffies;
@@ -989,7 +989,7 @@ void abort_timedouts(unsigned long __opaque)
 		packet = (struct hpsb_packet *)skb->data;
 
 		if (time_before(packet->sendtime + expire, jiffies)) {
-			__skb_unlink(skb, skb->list);
+			__skb_unlink(skb, &host->pending_packet_queue);
 			packet->state = hpsb_complete;
 			packet->ack_code = ACKX_TIMEOUT;
 			queue_packet_complete(packet);

drivers/isdn/act2000/capi.c

@@ -606,7 +606,7 @@ handle_ack(act2000_card *card, act2000_chan *chan, __u8 blocknr) {
                 if ((((m->msg.data_b3_req.fakencci >> 8) & 0xff) == chan->ncci) &&
 		    (m->msg.data_b3_req.blocknr == blocknr)) {
 			/* found corresponding DATA_B3_REQ */
-                        skb_unlink(tmp);
+                        skb_unlink(tmp, &card->ackq);
 			chan->queued -= m->msg.data_b3_req.datalen;
 			if (m->msg.data_b3_req.flags)
 				ret = m->msg.data_b3_req.datalen;

drivers/net/shaper.c

@@ -156,52 +156,6 @@ static int shaper_start_xmit(struct sk_buff *skb, struct net_device *dev)
  	 
  	SHAPERCB(skb)->shapelen= shaper_clocks(shaper,skb);
  	
-#ifdef SHAPER_COMPLEX /* and broken.. */
-
- 	while(ptr && ptr!=(struct sk_buff *)&shaper->sendq)
- 	{
- 		if(ptr->pri<skb->pri 
- 			&& jiffies - SHAPERCB(ptr)->shapeclock < SHAPER_MAXSLIP)
- 		{
- 			struct sk_buff *tmp=ptr->prev;
-
- 			/*
- 			 *	It goes before us therefore we slip the length
- 			 *	of the new frame.
- 			 */
-
- 			SHAPERCB(ptr)->shapeclock+=SHAPERCB(skb)->shapelen;
- 			SHAPERCB(ptr)->shapelatency+=SHAPERCB(skb)->shapelen;
-
- 			/*
- 			 *	The packet may have slipped so far back it
- 			 *	fell off.
- 			 */
- 			if(SHAPERCB(ptr)->shapelatency > SHAPER_LATENCY)
- 			{
- 				skb_unlink(ptr);
- 				dev_kfree_skb(ptr);
- 			}
- 			ptr=tmp;
- 		}
- 		else
- 			break;
- 	}
- 	if(ptr==NULL || ptr==(struct sk_buff *)&shaper->sendq)
- 		skb_queue_head(&shaper->sendq,skb);
- 	else
- 	{
- 		struct sk_buff *tmp;
- 		/*
- 		 *	Set the packet clock out time according to the
- 		 *	frames ahead. Im sure a bit of thought could drop
- 		 *	this loop.
- 		 */
- 		for(tmp=skb_peek(&shaper->sendq); tmp!=NULL && tmp!=ptr; tmp=tmp->next)
- 			SHAPERCB(skb)->shapeclock+=tmp->shapelen;
- 		skb_append(ptr,skb);
- 	}
-#else
 	{
 		struct sk_buff *tmp;
 		/*
@@ -220,7 +174,7 @@ static int shaper_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		} else
 			skb_queue_tail(&shaper->sendq, skb);
 	}
-#endif 	
+
 	if(sh_debug)
  		printk("Frame queued.\n");
  	if(skb_queue_len(&shaper->sendq)>SHAPER_QLEN)
@@ -302,7 +256,7 @@ static void shaper_kick(struct shaper *shaper)
 			 *	Pull the frame and get interrupts back on.
 			 */
 			 
-			skb_unlink(skb);
+			skb_unlink(skb, &shaper->sendq);
 			if (shaper->recovery < 
 			    SHAPERCB(skb)->shapeclock + SHAPERCB(skb)->shapelen)
 				shaper->recovery = SHAPERCB(skb)->shapeclock + SHAPERCB(skb)->shapelen;

drivers/net/wan/sdla_fr.c

@@ -445,7 +445,7 @@ void 	s508_s514_unlock(sdla_t *card, unsigned long *smp_flags);
 void 	s508_s514_lock(sdla_t *card, unsigned long *smp_flags);
 
 unsigned short calc_checksum (char *, int);
-static int setup_fr_header(struct sk_buff** skb,
+static int setup_fr_header(struct sk_buff *skb,
 			   struct net_device* dev, char op_mode);
 
 
@@ -1372,7 +1372,7 @@ static int if_send(struct sk_buff* skb, struct net_device* dev)
 	/* Move the if_header() code to here. By inserting frame
 	 * relay header in if_header() we would break the
 	 * tcpdump and other packet sniffers */
-	chan->fr_header_len = setup_fr_header(&skb,dev,chan->common.usedby);
+	chan->fr_header_len = setup_fr_header(skb,dev,chan->common.usedby);
 	if (chan->fr_header_len < 0 ){
 		++chan->ifstats.tx_dropped;
 		++card->wandev.stats.tx_dropped;
@@ -1597,8 +1597,6 @@ static int setup_for_delayed_transmit(struct net_device* dev,
 		return 1;
 	}
 
-	skb_unlink(skb);
-	
         chan->transmit_length = len;
 	chan->delay_skb = skb;
         
@@ -4871,18 +4869,15 @@ static void unconfig_fr (sdla_t *card)
 	}
 }
 
-static int setup_fr_header(struct sk_buff **skb_orig, struct net_device* dev,
+static int setup_fr_header(struct sk_buff *skb, struct net_device* dev,
 			   char op_mode)
 {
-	struct sk_buff *skb = *skb_orig;
 	fr_channel_t *chan=dev->priv;
 
-	if (op_mode == WANPIPE){
-
+	if (op_mode == WANPIPE) {
 		chan->fr_header[0]=Q922_UI;
 		
 		switch (htons(skb->protocol)){
-			
 		case ETH_P_IP:
 			chan->fr_header[1]=NLPID_IP;
 			break;
@@ -4894,16 +4889,14 @@ static int setup_fr_header(struct sk_buff **skb_orig, struct net_device* dev,
 	}
 
 	/* If we are in bridging mode, we must apply
-	 * an Ethernet header */
-	if (op_mode == BRIDGE || op_mode == BRIDGE_NODE){
-
-
+	 * an Ethernet header
+	 */
+	if (op_mode == BRIDGE || op_mode == BRIDGE_NODE) {
 		/* Encapsulate the packet as a bridged Ethernet frame. */
 #ifdef DEBUG
 		printk(KERN_INFO "%s: encapsulating skb for frame relay\n", 
 			dev->name);
 #endif
-		
 		chan->fr_header[0] = 0x03;
 		chan->fr_header[1] = 0x00;
 		chan->fr_header[2] = 0x80;
@@ -4916,7 +4909,6 @@ static int setup_fr_header(struct sk_buff **skb_orig, struct net_device* dev,
 		/* Yuck. */
 		skb->protocol = ETH_P_802_3;
 		return 8;
-
 	}
 		
 	return 0;

drivers/usb/net/usbnet.c

@@ -2903,19 +2903,18 @@ static struct net_device_stats *usbnet_get_stats (struct net_device *net)
  * completion callbacks.  2.5 should have fixed those bugs...
  */
 
-static void defer_bh (struct usbnet *dev, struct sk_buff *skb)
+static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 {
-	struct sk_buff_head	*list = skb->list;
 	unsigned long		flags;
 
-	spin_lock_irqsave (&list->lock, flags);
-	__skb_unlink (skb, list);
-	spin_unlock (&list->lock);
-	spin_lock (&dev->done.lock);
-	__skb_queue_tail (&dev->done, skb);
+	spin_lock_irqsave(&list->lock, flags);
+	__skb_unlink(skb, list);
+	spin_unlock(&list->lock);
+	spin_lock(&dev->done.lock);
+	__skb_queue_tail(&dev->done, skb);
 	if (dev->done.qlen == 1)
-		tasklet_schedule (&dev->bh);
-	spin_unlock_irqrestore (&dev->done.lock, flags);
+		tasklet_schedule(&dev->bh);
+	spin_unlock_irqrestore(&dev->done.lock, flags);
 }
 
 /* some work can't be done in tasklets, so we use keventd
@@ -3120,7 +3119,7 @@ static void rx_complete (struct urb *urb, struct pt_regs *regs)
 		break;
 	}
 
-	defer_bh (dev, skb);
+	defer_bh(dev, skb, &dev->rxq);
 
 	if (urb) {
 		if (netif_running (dev->net)
@@ -3490,7 +3489,7 @@ static void tx_complete (struct urb *urb, struct pt_regs *regs)
 
 	urb->dev = NULL;
 	entry->state = tx_done;
-	defer_bh (dev, skb);
+	defer_bh(dev, skb, &dev->txq);
 }
 
 /*-------------------------------------------------------------------------*/

include/linux/skbuff.h

@@ -204,7 +204,6 @@ struct sk_buff {
 	struct sk_buff		*next;
 	struct sk_buff		*prev;
 
-	struct sk_buff_head	*list;
 	struct sock		*sk;
 	struct timeval		stamp;
 	struct net_device	*dev;
@@ -597,7 +596,6 @@ static inline void __skb_queue_head(struct sk_buff_head *list,
 {
 	struct sk_buff *prev, *next;
 
-	newsk->list = list;
 	list->qlen++;
 	prev = (struct sk_buff *)list;
 	next = prev->next;
@@ -622,7 +620,6 @@ static inline void __skb_queue_tail(struct sk_buff_head *list,
 {
 	struct sk_buff *prev, *next;
 
-	newsk->list = list;
 	list->qlen++;
 	next = (struct sk_buff *)list;
 	prev = next->prev;
@@ -655,7 +652,6 @@ static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
 		next->prev   = prev;
 		prev->next   = next;
 		result->next = result->prev = NULL;
-		result->list = NULL;
 	}
 	return result;
 }
@@ -664,7 +660,7 @@ static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
 /*
  *	Insert a packet on a list.
  */
-extern void        skb_insert(struct sk_buff *old, struct sk_buff *newsk);
+extern void        skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
 static inline void __skb_insert(struct sk_buff *newsk,
 				struct sk_buff *prev, struct sk_buff *next,
 				struct sk_buff_head *list)
@@ -672,24 +668,23 @@ static inline void __skb_insert(struct sk_buff *newsk,
 	newsk->next = next;
 	newsk->prev = prev;
 	next->prev  = prev->next = newsk;
-	newsk->list = list;
 	list->qlen++;
 }
 
 /*
  *	Place a packet after a given packet in a list.
  */
-extern void	   skb_append(struct sk_buff *old, struct sk_buff *newsk);
-static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk)
+extern void	   skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
+static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
 {
-	__skb_insert(newsk, old, old->next, old->list);
+	__skb_insert(newsk, old, old->next, list);
 }
 
 /*
  * remove sk_buff from list. _Must_ be called atomically, and with
  * the list known..
  */
-extern void	   skb_unlink(struct sk_buff *skb);
+extern void	   skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
 static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
 {
 	struct sk_buff *next, *prev;
@@ -698,7 +693,6 @@ static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
 	next	   = skb->next;
 	prev	   = skb->prev;
 	skb->next  = skb->prev = NULL;
-	skb->list  = NULL;
 	next->prev = prev;
 	prev->next = next;
 }

net/atm/ipcommon.c

@@ -34,7 +34,6 @@
 
 void skb_migrate(struct sk_buff_head *from,struct sk_buff_head *to)
 {
-	struct sk_buff *skb;
 	unsigned long flags;
 	struct sk_buff *skb_from = (struct sk_buff *) from;
 	struct sk_buff *skb_to = (struct sk_buff *) to;
@@ -47,8 +46,6 @@ void skb_migrate(struct sk_buff_head *from,struct sk_buff_head *to)
 	prev->next = skb_to;
 	to->prev->next = from->next;
 	to->prev = from->prev;
-	for (skb = from->next; skb != skb_to; skb = skb->next)
-		skb->list = to;
 	to->qlen += from->qlen;
 	spin_unlock(&to->lock);
 	from->prev = skb_from;

net/ax25/ax25_subr.c

@@ -76,7 +76,7 @@ void ax25_requeue_frames(ax25_cb *ax25)
 		if (skb_prev == NULL)
 			skb_queue_head(&ax25->write_queue, skb);
 		else
-			skb_append(skb_prev, skb);
+			skb_append(skb_prev, skb, &ax25->write_queue);
 		skb_prev = skb;
 	}
 }

net/core/skbuff.c

@@ -281,8 +281,6 @@ void kfree_skbmem(struct sk_buff *skb)
 
 void __kfree_skb(struct sk_buff *skb)
 {
-	BUG_ON(skb->list != NULL);
-
 	dst_release(skb->dst);
 #ifdef CONFIG_XFRM
 	secpath_put(skb->sp);
@@ -333,7 +331,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask)
 #define C(x) n->x = skb->x
 
 	n->next = n->prev = NULL;
-	n->list = NULL;
 	n->sk = NULL;
 	C(stamp);
 	C(dev);
@@ -403,7 +400,6 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 	 */
 	unsigned long offset = new->data - old->data;
 
-	new->list	= NULL;
 	new->sk		= NULL;
 	new->dev	= old->dev;
 	new->real_dev	= old->real_dev;
@@ -1342,50 +1338,43 @@ void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk)
 	__skb_queue_tail(list, newsk);
 	spin_unlock_irqrestore(&list->lock, flags);
 }
+
 /**
  *	skb_unlink	-	remove a buffer from a list
  *	@skb: buffer to remove
+ *	@list: list to use
  *
- *	Place a packet after a given packet in a list. The list locks are taken
- *	and this function is atomic with respect to other list locked calls
+ *	Remove a packet from a list. The list locks are taken and this
+ *	function is atomic with respect to other list locked calls
  *
- *	Works even without knowing the list it is sitting on, which can be
- *	handy at times. It also means that THE LIST MUST EXIST when you
- *	unlink. Thus a list must have its contents unlinked before it is
- *	destroyed.
+ *	You must know what list the SKB is on.
  */
-void skb_unlink(struct sk_buff *skb)
+void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
 {
-	struct sk_buff_head *list = skb->list;
-
-	if (list) {
-		unsigned long flags;
+	unsigned long flags;
 
-		spin_lock_irqsave(&list->lock, flags);
-		if (skb->list == list)
-			__skb_unlink(skb, skb->list);
-		spin_unlock_irqrestore(&list->lock, flags);
-	}
+	spin_lock_irqsave(&list->lock, flags);
+	__skb_unlink(skb, list);
+	spin_unlock_irqrestore(&list->lock, flags);
 }
 
-
 /**
  *	skb_append	-	append a buffer
  *	@old: buffer to insert after
  *	@newsk: buffer to insert
+ *	@list: list to use
  *
  *	Place a packet after a given packet in a list. The list locks are taken
  *	and this function is atomic with respect to other list locked calls.
  *	A buffer cannot be placed on two lists at the same time.
  */
-
-void skb_append(struct sk_buff *old, struct sk_buff *newsk)
+void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&old->list->lock, flags);
-	__skb_append(old, newsk);
-	spin_unlock_irqrestore(&old->list->lock, flags);
+	spin_lock_irqsave(&list->lock, flags);
+	__skb_append(old, newsk, list);
+	spin_unlock_irqrestore(&list->lock, flags);
 }
 
 
@@ -1393,19 +1382,21 @@ void skb_append(struct sk_buff *old, struct sk_buff *newsk)
  *	skb_insert	-	insert a buffer
  *	@old: buffer to insert before
  *	@newsk: buffer to insert
+ *	@list: list to use
+ *
+ *	Place a packet before a given packet in a list. The list locks are
+ * 	taken and this function is atomic with respect to other list locked
+ *	calls.
  *
- *	Place a packet before a given packet in a list. The list locks are taken
- *	and this function is atomic with respect to other list locked calls
  *	A buffer cannot be placed on two lists at the same time.
  */
-
-void skb_insert(struct sk_buff *old, struct sk_buff *newsk)
+void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&old->list->lock, flags);
-	__skb_insert(newsk, old->prev, old, old->list);
-	spin_unlock_irqrestore(&old->list->lock, flags);
+	spin_lock_irqsave(&list->lock, flags);
+	__skb_insert(newsk, old->prev, old, list);
+	spin_unlock_irqrestore(&list->lock, flags);
 }
 
 #if 0

net/decnet/af_decnet.c

@@ -1763,7 +1763,7 @@ static int dn_recvmsg(struct kiocb *iocb, struct socket *sock,
 		nskb = skb->next;
 
 		if (skb->len == 0) {
-			skb_unlink(skb);
+			skb_unlink(skb, queue);
 			kfree_skb(skb);
 			/* 
 			 * N.B. Don't refer to skb or cb after this point

net/decnet/dn_nsp_out.c

@@ -479,7 +479,7 @@ int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff
 		xmit_count = cb2->xmit_count;
 		segnum = cb2->segnum;
 		/* Remove and drop ack'ed packet */
-		skb_unlink(ack);
+		skb_unlink(ack, q);
 		kfree_skb(ack);
 		ack = NULL;
 

net/econet/af_econet.c

@@ -869,7 +869,7 @@ static void aun_tx_ack(unsigned long seq, int result)
 
 foundit:
 	tx_result(skb->sk, eb->cookie, result);
-	skb_unlink(skb);
+	skb_unlink(skb, &aun_queue);
 	spin_unlock_irqrestore(&aun_queue_lock, flags);
 	kfree_skb(skb);
 }
@@ -947,7 +947,7 @@ static void ab_cleanup(unsigned long h)
 		{
 			tx_result(skb->sk, eb->cookie, 
 				  ECTYPE_TRANSMIT_NOT_PRESENT);
-			skb_unlink(skb);
+			skb_unlink(skb, &aun_queue);
 			kfree_skb(skb);
 		}
 		skb = newskb;

net/ipv4/tcp.c

@@ -975,7 +975,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	if (!skb->len) {
 		if (sk->sk_send_head == skb)
 			sk->sk_send_head = NULL;
-		__skb_unlink(skb, skb->list);
+		__skb_unlink(skb, &sk->sk_write_queue);
 		sk_stream_free_skb(sk, skb);
 	}
 

net/ipv4/tcp_input.c

@@ -2085,7 +2085,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p, s32 *seq_usrtt
 			seq_rtt = now - scb->when;
 		tcp_dec_pcount_approx(&tp->fackets_out, skb);
 		tcp_packets_out_dec(tp, skb);
-		__skb_unlink(skb, skb->list);
+		__skb_unlink(skb, &sk->sk_write_queue);
 		sk_stream_free_skb(sk, skb);
 	}
 
@@ -2853,7 +2853,7 @@ static void tcp_ofo_queue(struct sock *sk)
 
 		if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) {
 			SOCK_DEBUG(sk, "ofo packet was already received \n");
-			__skb_unlink(skb, skb->list);
+			__skb_unlink(skb, &tp->out_of_order_queue);
 			__kfree_skb(skb);
 			continue;
 		}
@@ -2861,7 +2861,7 @@ static void tcp_ofo_queue(struct sock *sk)
 			   tp->rcv_nxt, TCP_SKB_CB(skb)->seq,
 			   TCP_SKB_CB(skb)->end_seq);
 
-		__skb_unlink(skb, skb->list);
+		__skb_unlink(skb, &tp->out_of_order_queue);
 		__skb_queue_tail(&sk->sk_receive_queue, skb);
 		tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
 		if(skb->h.th->fin)
@@ -3027,7 +3027,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 		u32 end_seq = TCP_SKB_CB(skb)->end_seq;
 
 		if (seq == TCP_SKB_CB(skb1)->end_seq) {
-			__skb_append(skb1, skb);
+			__skb_append(skb1, skb, &tp->out_of_order_queue);
 
 			if (!tp->rx_opt.num_sacks ||
 			    tp->selective_acks[0].end_seq != seq)
@@ -3071,7 +3071,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 			       tcp_dsack_extend(tp, TCP_SKB_CB(skb1)->seq, end_seq);
 			       break;
 		       }
-		       __skb_unlink(skb1, skb1->list);
+		       __skb_unlink(skb1, &tp->out_of_order_queue);
 		       tcp_dsack_extend(tp, TCP_SKB_CB(skb1)->seq, TCP_SKB_CB(skb1)->end_seq);
 		       __kfree_skb(skb1);
 		}
@@ -3088,8 +3088,9 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
  * simplifies code)
  */
 static void
-tcp_collapse(struct sock *sk, struct sk_buff *head,
-	     struct sk_buff *tail, u32 start, u32 end)
+tcp_collapse(struct sock *sk, struct sk_buff_head *list,
+	     struct sk_buff *head, struct sk_buff *tail,
+	     u32 start, u32 end)
 {
 	struct sk_buff *skb;
 
@@ -3099,7 +3100,7 @@ tcp_collapse(struct sock *sk, struct sk_buff *head,
 		/* No new bits? It is possible on ofo queue. */
 		if (!before(start, TCP_SKB_CB(skb)->end_seq)) {
 			struct sk_buff *next = skb->next;
-			__skb_unlink(skb, skb->list);
+			__skb_unlink(skb, list);
 			__kfree_skb(skb);
 			NET_INC_STATS_BH(LINUX_MIB_TCPRCVCOLLAPSED);
 			skb = next;
@@ -3145,7 +3146,7 @@ tcp_collapse(struct sock *sk, struct sk_buff *head,
 		nskb->mac.raw = nskb->head + (skb->mac.raw-skb->head);
 		memcpy(nskb->cb, skb->cb, sizeof(skb->cb));
 		TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start;
-		__skb_insert(nskb, skb->prev, skb, skb->list);
+		__skb_insert(nskb, skb->prev, skb, list);
 		sk_stream_set_owner_r(nskb, sk);
 
 		/* Copy data, releasing collapsed skbs. */
@@ -3164,7 +3165,7 @@ tcp_collapse(struct sock *sk, struct sk_buff *head,
 			}
 			if (!before(start, TCP_SKB_CB(skb)->end_seq)) {
 				struct sk_buff *next = skb->next;
-				__skb_unlink(skb, skb->list);
+				__skb_unlink(skb, list);
 				__kfree_skb(skb);
 				NET_INC_STATS_BH(LINUX_MIB_TCPRCVCOLLAPSED);
 				skb = next;
@@ -3200,7 +3201,8 @@ static void tcp_collapse_ofo_queue(struct sock *sk)
 		if (skb == (struct sk_buff *)&tp->out_of_order_queue ||
 		    after(TCP_SKB_CB(skb)->seq, end) ||
 		    before(TCP_SKB_CB(skb)->end_seq, start)) {
-			tcp_collapse(sk, head, skb, start, end);
+			tcp_collapse(sk, &tp->out_of_order_queue,
+				     head, skb, start, end);
 			head = skb;
 			if (skb == (struct sk_buff *)&tp->out_of_order_queue)
 				break;
@@ -3237,7 +3239,8 @@ static int tcp_prune_queue(struct sock *sk)
 		tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss);
 
 	tcp_collapse_ofo_queue(sk);
-	tcp_collapse(sk, sk->sk_receive_queue.next,
+	tcp_collapse(sk, &sk->sk_receive_queue,
+		     sk->sk_receive_queue.next,
 		     (struct sk_buff*)&sk->sk_receive_queue,
 		     tp->copied_seq, tp->rcv_nxt);
 	sk_stream_mem_reclaim(sk);
@@ -3462,7 +3465,7 @@ static void tcp_check_urg(struct sock * sk, struct tcphdr * th)
 		struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
 		tp->copied_seq++;
 		if (skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq)) {
-			__skb_unlink(skb, skb->list);
+			__skb_unlink(skb, &sk->sk_receive_queue);
 			__kfree_skb(skb);
 		}
 	}

net/ipv4/tcp_output.c

@@ -505,7 +505,7 @@ static int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned
 
 	/* Link BUFF into the send queue. */
 	skb_header_release(buff);
-	__skb_append(skb, buff);
+	__skb_append(skb, buff, &sk->sk_write_queue);
 
 	return 0;
 }
@@ -893,7 +893,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
 
 	/* Link BUFF into the send queue. */
 	skb_header_release(buff);
-	__skb_append(skb, buff);
+	__skb_append(skb, buff, &sk->sk_write_queue);
 
 	return 0;
 }
@@ -1238,7 +1238,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
 		       tcp_skb_pcount(next_skb) != 1);
 
 		/* Ok.  We will be able to collapse the packet. */
-		__skb_unlink(next_skb, next_skb->list);
+		__skb_unlink(next_skb, &sk->sk_write_queue);
 
 		memcpy(skb_put(skb, next_skb_size), next_skb->data, next_skb_size);
 

net/irda/irlap_frame.c

@@ -988,9 +988,6 @@ void irlap_resend_rejected_frames(struct irlap_cb *self, int command)
 			IRDA_DEBUG(0, "%s(), unable to copy\n", __FUNCTION__);
 			return;
 		}
-		/* Unlink tx_skb from list */
-		tx_skb->next = tx_skb->prev = NULL;
-		tx_skb->list = NULL;
 
 		/* Clear old Nr field + poll bit */
 		tx_skb->data[1] &= 0x0f;
@@ -1063,9 +1060,6 @@ void irlap_resend_rejected_frame(struct irlap_cb *self, int command)
 			IRDA_DEBUG(0, "%s(), unable to copy\n", __FUNCTION__);
 			return;
 		}
-		/* Unlink tx_skb from list */
-		tx_skb->next = tx_skb->prev = NULL;
-		tx_skb->list = NULL;
 
 		/* Clear old Nr field + poll bit */
 		tx_skb->data[1] &= 0x0f;

net/lapb/lapb_subr.c

@@ -78,7 +78,7 @@ void lapb_requeue_frames(struct lapb_cb *lapb)
 		if (!skb_prev)
 			skb_queue_head(&lapb->write_queue, skb);
 		else
-			skb_append(skb_prev, skb);
+			skb_append(skb_prev, skb, &lapb->write_queue);
 		skb_prev = skb;
 	}
 }

net/llc/af_llc.c

@@ -714,7 +714,7 @@ static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
 	if (uaddr)
 		memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
 	msg->msg_namelen = sizeof(*uaddr);
-	if (!skb->list) {
+	if (!skb->next) {
 dgram_free:
 		kfree_skb(skb);
 	}

net/llc/llc_conn.c

@@ -71,7 +71,11 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
 
 	if (!ev->ind_prim && !ev->cfm_prim) {
 		/* indicate or confirm not required */
-		if (!skb->list)
+		/* XXX this is not very pretty, perhaps we should store
+		 * XXX indicate/confirm-needed state in the llc_conn_state_ev
+		 * XXX control block of the SKB instead? -DaveM
+		 */
+		if (!skb->next)
 			goto out_kfree_skb;
 		goto out_skb_put;
 	}

net/netrom/nr_subr.c

@@ -77,7 +77,7 @@ void nr_requeue_frames(struct sock *sk)
 		if (skb_prev == NULL)
 			skb_queue_head(&sk->sk_write_queue, skb);
 		else
-			skb_append(skb_prev, skb);
+			skb_append(skb_prev, skb, &sk->sk_write_queue);
 		skb_prev = skb;
 	}
 }

net/rose/rose_subr.c

@@ -74,7 +74,7 @@ void rose_requeue_frames(struct sock *sk)
 		if (skb_prev == NULL)
 			skb_queue_head(&sk->sk_write_queue, skb);
 		else
-			skb_append(skb_prev, skb);
+			skb_append(skb_prev, skb, &sk->sk_write_queue);
 		skb_prev = skb;
 	}
 }

net/sctp/socket.c

@@ -4892,7 +4892,7 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
 		event = sctp_skb2event(skb);
 		if (event->asoc == assoc) {
-			__skb_unlink(skb, skb->list);
+			__skb_unlink(skb, &oldsk->sk_receive_queue);
 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
 		}
 	}
@@ -4921,7 +4921,7 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
 			event = sctp_skb2event(skb);
 			if (event->asoc == assoc) {
-				__skb_unlink(skb, skb->list);
+				__skb_unlink(skb, &oldsp->pd_lobby);
 				__skb_queue_tail(queue, skb);
 			}
 		}

net/sctp/ulpqueue.c

@@ -50,9 +50,9 @@
 
 /* Forward declarations for internal helpers.  */
 static struct sctp_ulpevent * sctp_ulpq_reasm(struct sctp_ulpq *ulpq,
-						struct sctp_ulpevent *);
+					      struct sctp_ulpevent *);
 static struct sctp_ulpevent * sctp_ulpq_order(struct sctp_ulpq *,
-						struct sctp_ulpevent *);
+					      struct sctp_ulpevent *);
 
 /* 1st Level Abstractions */
 
@@ -125,7 +125,9 @@ int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,
 		event = sctp_ulpq_order(ulpq, event);
 	}
 
-	/* Send event to the ULP.  */
+	/* Send event to the ULP.  'event' is the sctp_ulpevent for
+	 * very first SKB on the 'temp' list.
+	 */
 	if (event)
 		sctp_ulpq_tail_event(ulpq, event);
 
@@ -158,14 +160,18 @@ static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq)
 	return sctp_clear_pd(ulpq->asoc->base.sk);
 }
 
-
-
+/* If the SKB of 'event' is on a list, it is the first such member
+ * of that list.
+ */
 int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
 {
 	struct sock *sk = ulpq->asoc->base.sk;
-	struct sk_buff_head *queue;
+	struct sk_buff_head *queue, *skb_list;
+	struct sk_buff *skb = sctp_event2skb(event);
 	int clear_pd = 0;
 
+	skb_list = (struct sk_buff_head *) skb->prev;
+
 	/* If the socket is just going to throw this away, do not
 	 * even try to deliver it.
 	 */
@@ -197,10 +203,10 @@ int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
 	/* If we are harvesting multiple skbs they will be
 	 * collected on a list.
 	 */
-	if (sctp_event2skb(event)->list)
-		sctp_skb_list_tail(sctp_event2skb(event)->list, queue);
+	if (skb_list)
+		sctp_skb_list_tail(skb_list, queue);
 	else
-		__skb_queue_tail(queue, sctp_event2skb(event));
+		__skb_queue_tail(queue, skb);
 
 	/* Did we just complete partial delivery and need to get
 	 * rolling again?  Move pending data to the receive
@@ -214,10 +220,11 @@ int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
 	return 1;
 
 out_free:
-	if (sctp_event2skb(event)->list)
-		sctp_queue_purge_ulpevents(sctp_event2skb(event)->list);
+	if (skb_list)
+		sctp_queue_purge_ulpevents(skb_list);
 	else
 		sctp_ulpevent_free(event);
+
 	return 0;
 }
 
@@ -269,7 +276,7 @@ static inline void sctp_ulpq_store_reasm(struct sctp_ulpq *ulpq,
  * payload was fragmented on the way and ip had to reassemble them.
  * We add the rest of skb's to the first skb's fraglist.
  */
-static struct sctp_ulpevent *sctp_make_reassembled_event(struct sk_buff *f_frag, struct sk_buff *l_frag)
+static struct sctp_ulpevent *sctp_make_reassembled_event(struct sk_buff_head *queue, struct sk_buff *f_frag, struct sk_buff *l_frag)
 {
 	struct sk_buff *pos;
 	struct sctp_ulpevent *event;
@@ -294,7 +301,7 @@ static struct sctp_ulpevent *sctp_make_reassembled_event(struct sk_buff *f_frag,
 		skb_shinfo(f_frag)->frag_list = pos;
 
 	/* Remove the first fragment from the reassembly queue.  */
-	__skb_unlink(f_frag, f_frag->list);
+	__skb_unlink(f_frag, queue);
 	while (pos) {
 
 		pnext = pos->next;
@@ -304,7 +311,7 @@ static struct sctp_ulpevent *sctp_make_reassembled_event(struct sk_buff *f_frag,
 		f_frag->data_len += pos->len;
 
 		/* Remove the fragment from the reassembly queue.  */
-		__skb_unlink(pos, pos->list);
+		__skb_unlink(pos, queue);
 	
 		/* Break if we have reached the last fragment.  */
 		if (pos == l_frag)
@@ -375,7 +382,7 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_u
 done:
 	return retval;
 found:
-	retval = sctp_make_reassembled_event(first_frag, pos);
+	retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, pos);
 	if (retval)
 		retval->msg_flags |= MSG_EOR;
 	goto done;
@@ -435,7 +442,7 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq
 	 * further.
 	 */
 done:
-	retval = sctp_make_reassembled_event(first_frag, last_frag);
+	retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, last_frag);
 	if (retval && is_last)
 		retval->msg_flags |= MSG_EOR;
 
@@ -527,7 +534,7 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *u
 	 * further.
 	 */
 done:
-	retval = sctp_make_reassembled_event(first_frag, last_frag);
+	retval = sctp_make_reassembled_event(&ulpq->reasm, first_frag, last_frag);
 	return retval;
 }
 
@@ -537,6 +544,7 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *u
 static inline void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq,
 					      struct sctp_ulpevent *event)
 {
+	struct sk_buff_head *event_list;
 	struct sk_buff *pos, *tmp;
 	struct sctp_ulpevent *cevent;
 	struct sctp_stream *in;
@@ -547,6 +555,8 @@ static inline void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq,
 	ssn = event->ssn;
 	in  = &ulpq->asoc->ssnmap->in;
 
+	event_list = (struct sk_buff_head *) sctp_event2skb(event)->prev;
+
 	/* We are holding the chunks by stream, by SSN.  */
 	sctp_skb_for_each(pos, &ulpq->lobby, tmp) {
 		cevent = (struct sctp_ulpevent *) pos->cb;
@@ -567,10 +577,10 @@ static inline void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq,
 		/* Found it, so mark in the ssnmap. */
 		sctp_ssn_next(in, sid);
 
-		__skb_unlink(pos, pos->list);
+		__skb_unlink(pos, &ulpq->lobby);
 
 		/* Attach all gathered skbs to the event.  */
-		__skb_queue_tail(sctp_event2skb(event)->list, pos);
+		__skb_queue_tail(event_list, pos);
 	}
 }
 
@@ -626,7 +636,7 @@ static inline void sctp_ulpq_store_ordered(struct sctp_ulpq *ulpq,
 }
 
 static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *ulpq,
-						struct sctp_ulpevent *event)
+					     struct sctp_ulpevent *event)
 {
 	__u16 sid, ssn;
 	struct sctp_stream *in;
@@ -667,7 +677,7 @@ static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq)
 {
 	struct sk_buff *pos, *tmp;
 	struct sctp_ulpevent *cevent;
-	struct sctp_ulpevent *event = NULL;
+	struct sctp_ulpevent *event;
 	struct sctp_stream *in;
 	struct sk_buff_head temp;
 	__u16 csid, cssn;
@@ -675,6 +685,8 @@ static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq)
 	in  = &ulpq->asoc->ssnmap->in;
 
 	/* We are holding the chunks by stream, by SSN.  */
+	skb_queue_head_init(&temp);
+	event = NULL;
 	sctp_skb_for_each(pos, &ulpq->lobby, tmp) {
 		cevent = (struct sctp_ulpevent *) pos->cb;
 		csid = cevent->stream;
@@ -686,19 +698,20 @@ static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq)
 		/* Found it, so mark in the ssnmap. */	       
 		sctp_ssn_next(in, csid);
 
-		__skb_unlink(pos, pos->list);
+		__skb_unlink(pos, &ulpq->lobby);
 		if (!event) {						
 			/* Create a temporary list to collect chunks on.  */
 			event = sctp_skb2event(pos);
-			skb_queue_head_init(&temp);
 			__skb_queue_tail(&temp, sctp_event2skb(event));
 		} else {
 			/* Attach all gathered skbs to the event.  */
-			__skb_queue_tail(sctp_event2skb(event)->list, pos);
+			__skb_queue_tail(&temp, pos);
 		}
 	}
 
-	/* Send event to the ULP.  */
+	/* Send event to the ULP.  'event' is the sctp_ulpevent for
+	 * very first SKB on the 'temp' list.
+	 */
 	if (event)
 		sctp_ulpq_tail_event(ulpq, event);
 }

net/unix/garbage.c

@@ -286,16 +286,16 @@ void unix_gc(void)
 			skb = skb_peek(&s->sk_receive_queue);
 			while (skb &&
 			       skb != (struct sk_buff *)&s->sk_receive_queue) {
-				nextsk=skb->next;
+				nextsk = skb->next;
 				/*
 				 *	Do we have file descriptors ?
 				 */
-				if(UNIXCB(skb).fp)
-				{
-					__skb_unlink(skb, skb->list);
-					__skb_queue_tail(&hitlist,skb);
+				if (UNIXCB(skb).fp) {
+					__skb_unlink(skb,
+						     &s->sk_receive_queue);
+					__skb_queue_tail(&hitlist, skb);
 				}
-				skb=nextsk;
+				skb = nextsk;
 			}
 			spin_unlock(&s->sk_receive_queue.lock);
 		}

net/x25/x25_subr.c

@@ -80,7 +80,7 @@ void x25_requeue_frames(struct sock *sk)
 		if (!skb_prev)
 			skb_queue_head(&sk->sk_write_queue, skb);
 		else
-			skb_append(skb_prev, skb);
+			skb_append(skb_prev, skb, &sk->sk_write_queue);
 		skb_prev = skb;
 	}
 }