[NET]: Remove gratuitous use of skb->tail in network drivers.

Many drivers use skb->tail unnecessarily.

In these situations, the code roughly looks like:

	dev = dev_alloc_skb(...);

	[optional] skb_reserve(skb, ...);

	... skb->tail ...

But even if the skb_reserve() happens, skb->data equals
skb->tail.  So it doesn't make any sense to use anything
other than skb->data in these cases.

Another case was the s2io.c driver directly mucking with
the skb->data and skb->tail pointers.  It really just wanted
to do an skb_reserve(), so that's what the code was changed
to do instead.

Another reason I'm making this change as it allows some SKB
cleanups I have planned simpler to merge.  In those cleanups,
skb->head, skb->tail, and skb->end pointers are removed, and
replaced with skb->head_room and skb->tail_room integers.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jgarzik@pobox.com>

drivers/net/3c515.c

@@ -822,7 +822,7 @@ static int corkscrew_open(struct net_device *dev)
 				break;	/* Bad news!  */
 			skb->dev = dev;	/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
-			vp->rx_ring[i].addr = isa_virt_to_bus(skb->tail);
+			vp->rx_ring[i].addr = isa_virt_to_bus(skb->data);
 		}
 		vp->rx_ring[i - 1].next = isa_virt_to_bus(&vp->rx_ring[0]);	/* Wrap the ring. */
 		outl(isa_virt_to_bus(&vp->rx_ring[0]), ioaddr + UpListPtr);
@@ -1406,7 +1406,7 @@ static int boomerang_rx(struct net_device *dev)
 				break;	/* Bad news!  */
 			skb->dev = dev;	/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
-			vp->rx_ring[entry].addr = isa_virt_to_bus(skb->tail);
+			vp->rx_ring[entry].addr = isa_virt_to_bus(skb->data);
 			vp->rx_skbuff[entry] = skb;
 		}
 		vp->rx_ring[entry].status = 0;	/* Clear complete bit. */

drivers/net/3c59x.c

@@ -1802,7 +1802,7 @@ vortex_open(struct net_device *dev)
 				break;			/* Bad news!  */
 			skb->dev = dev;			/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
-			vp->rx_ring[i].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->tail, PKT_BUF_SZ, PCI_DMA_FROMDEVICE));
+			vp->rx_ring[i].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, PKT_BUF_SZ, PCI_DMA_FROMDEVICE));
 		}
 		if (i != RX_RING_SIZE) {
 			int j;
@@ -2632,7 +2632,7 @@ boomerang_rx(struct net_device *dev)
 				pci_dma_sync_single_for_cpu(VORTEX_PCI(vp), dma, PKT_BUF_SZ, PCI_DMA_FROMDEVICE);
 				/* 'skb_put()' points to the start of sk_buff data area. */
 				memcpy(skb_put(skb, pkt_len),
-					   vp->rx_skbuff[entry]->tail,
+					   vp->rx_skbuff[entry]->data,
 					   pkt_len);
 				pci_dma_sync_single_for_device(VORTEX_PCI(vp), dma, PKT_BUF_SZ, PCI_DMA_FROMDEVICE);
 				vp->rx_copy++;
@@ -2678,7 +2678,7 @@ boomerang_rx(struct net_device *dev)
 			}
 			skb->dev = dev;			/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
-			vp->rx_ring[entry].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->tail, PKT_BUF_SZ, PCI_DMA_FROMDEVICE));
+			vp->rx_ring[entry].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, PKT_BUF_SZ, PCI_DMA_FROMDEVICE));
 			vp->rx_skbuff[entry] = skb;
 		}
 		vp->rx_ring[entry].status = 0;	/* Clear complete bit. */

drivers/net/8139cp.c

@@ -596,7 +596,7 @@ static int cp_rx_poll (struct net_device *dev, int *budget)
 
 		mapping =
 		cp->rx_skb[rx_tail].mapping =
-			pci_map_single(cp->pdev, new_skb->tail,
+			pci_map_single(cp->pdev, new_skb->data,
 				       buflen, PCI_DMA_FROMDEVICE);
 		cp->rx_skb[rx_tail].skb = new_skb;
 
@@ -1101,7 +1101,7 @@ static int cp_refill_rx (struct cp_private *cp)
 		skb_reserve(skb, RX_OFFSET);
 
 		cp->rx_skb[i].mapping = pci_map_single(cp->pdev,
-			skb->tail, cp->rx_buf_sz, PCI_DMA_FROMDEVICE);
+			skb->data, cp->rx_buf_sz, PCI_DMA_FROMDEVICE);
 		cp->rx_skb[i].skb = skb;
 
 		cp->rx_ring[i].opts2 = 0;

drivers/net/82596.c

@@ -546,11 +546,11 @@ static inline void init_rx_bufs(struct net_device *dev)
 		rbd->b_next = WSWAPrbd(virt_to_bus(rbd+1));
 		rbd->b_addr = WSWAPrbd(virt_to_bus(rbd));
 		rbd->skb = skb;
-		rbd->v_data = skb->tail;
-		rbd->b_data = WSWAPchar(virt_to_bus(skb->tail));
+		rbd->v_data = skb->data;
+		rbd->b_data = WSWAPchar(virt_to_bus(skb->data));
 		rbd->size = PKT_BUF_SZ;
 #ifdef __mc68000__
-		cache_clear(virt_to_phys(skb->tail), PKT_BUF_SZ);
+		cache_clear(virt_to_phys(skb->data), PKT_BUF_SZ);
 #endif
 	}
 	lp->rbd_head = lp->rbds;
@@ -816,10 +816,10 @@ static inline int i596_rx(struct net_device *dev)
 				rx_in_place = 1;
 				rbd->skb = newskb;
 				newskb->dev = dev;
-				rbd->v_data = newskb->tail;
-				rbd->b_data = WSWAPchar(virt_to_bus(newskb->tail));
+				rbd->v_data = newskb->data;
+				rbd->b_data = WSWAPchar(virt_to_bus(newskb->data));
 #ifdef __mc68000__
-				cache_clear(virt_to_phys(newskb->tail), PKT_BUF_SZ);
+				cache_clear(virt_to_phys(newskb->data), PKT_BUF_SZ);
 #endif
 			}
 			else
@@ -840,7 +840,7 @@ static inline int i596_rx(struct net_device *dev)
 				skb->protocol=eth_type_trans(skb,dev);
 				skb->len = pkt_len;
 #ifdef __mc68000__
-				cache_clear(virt_to_phys(rbd->skb->tail),
+				cache_clear(virt_to_phys(rbd->skb->data),
 						pkt_len);
 #endif
 				netif_rx(skb);

drivers/net/dl2k.c

@@ -547,7 +547,7 @@ rio_timer (unsigned long data)
 				skb_reserve (skb, 2);
 				np->rx_ring[entry].fraginfo =
 				    cpu_to_le64 (pci_map_single
-					 (np->pdev, skb->tail, np->rx_buf_sz,
+					 (np->pdev, skb->data, np->rx_buf_sz,
 					  PCI_DMA_FROMDEVICE));
 			}
 			np->rx_ring[entry].fraginfo |=
@@ -618,7 +618,7 @@ alloc_list (struct net_device *dev)
 		/* Rubicon now supports 40 bits of addressing space. */
 		np->rx_ring[i].fraginfo =
 		    cpu_to_le64 ( pci_map_single (
-			 	  np->pdev, skb->tail, np->rx_buf_sz,
+			 	  np->pdev, skb->data, np->rx_buf_sz,
 				  PCI_DMA_FROMDEVICE));
 		np->rx_ring[i].fraginfo |= cpu_to_le64 (np->rx_buf_sz) << 48;
 	}
@@ -906,7 +906,7 @@ receive_packet (struct net_device *dev)
 				/* 16 byte align the IP header */
 				skb_reserve (skb, 2);
 				eth_copy_and_sum (skb,
-						  np->rx_skbuff[entry]->tail,
+						  np->rx_skbuff[entry]->data,
 						  pkt_len, 0);
 				skb_put (skb, pkt_len);
 				pci_dma_sync_single_for_device(np->pdev,
@@ -950,7 +950,7 @@ receive_packet (struct net_device *dev)
 			skb_reserve (skb, 2);
 			np->rx_ring[entry].fraginfo =
 			    cpu_to_le64 (pci_map_single
-					 (np->pdev, skb->tail, np->rx_buf_sz,
+					 (np->pdev, skb->data, np->rx_buf_sz,
 					  PCI_DMA_FROMDEVICE));
 		}
 		np->rx_ring[entry].fraginfo |=

drivers/net/eepro100.c

@@ -1269,7 +1269,7 @@ speedo_init_rx_ring(struct net_device *dev)
 		if (skb == NULL)
 			break;			/* OK.  Just initially short of Rx bufs. */
 		skb->dev = dev;			/* Mark as being used by this device. */
-		rxf = (struct RxFD *)skb->tail;
+		rxf = (struct RxFD *)skb->data;
 		sp->rx_ringp[i] = rxf;
 		sp->rx_ring_dma[i] =
 			pci_map_single(sp->pdev, rxf,
@@ -1661,7 +1661,7 @@ static inline struct RxFD *speedo_rx_alloc(struct net_device *dev, int entry)
 		sp->rx_ringp[entry] = NULL;
 		return NULL;
 	}
-	rxf = sp->rx_ringp[entry] = (struct RxFD *)skb->tail;
+	rxf = sp->rx_ringp[entry] = (struct RxFD *)skb->data;
 	sp->rx_ring_dma[entry] =
 		pci_map_single(sp->pdev, rxf,
 					   PKT_BUF_SZ + sizeof(struct RxFD), PCI_DMA_FROMDEVICE);
@@ -1808,10 +1808,10 @@ speedo_rx(struct net_device *dev)
 
 #if 1 || USE_IP_CSUM
 				/* Packet is in one chunk -- we can copy + cksum. */
-				eth_copy_and_sum(skb, sp->rx_skbuff[entry]->tail, pkt_len, 0);
+				eth_copy_and_sum(skb, sp->rx_skbuff[entry]->data, pkt_len, 0);
 				skb_put(skb, pkt_len);
 #else
-				memcpy(skb_put(skb, pkt_len), sp->rx_skbuff[entry]->tail,
+				memcpy(skb_put(skb, pkt_len), sp->rx_skbuff[entry]->data,
 					   pkt_len);
 #endif
 				pci_dma_sync_single_for_device(sp->pdev, sp->rx_ring_dma[entry],

drivers/net/epic100.c

@@ -1003,7 +1003,7 @@ static void epic_init_ring(struct net_device *dev)
 		skb->dev = dev;			/* Mark as being used by this device. */
 		skb_reserve(skb, 2);	/* 16 byte align the IP header. */
 		ep->rx_ring[i].bufaddr = pci_map_single(ep->pci_dev, 
-			skb->tail, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
+			skb->data, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
 		ep->rx_ring[i].rxstatus = cpu_to_le32(DescOwn);
 	}
 	ep->dirty_rx = (unsigned int)(i - RX_RING_SIZE);
@@ -1274,7 +1274,7 @@ static int epic_rx(struct net_device *dev, int budget)
 							    ep->rx_ring[entry].bufaddr,
 							    ep->rx_buf_sz,
 							    PCI_DMA_FROMDEVICE);
-				eth_copy_and_sum(skb, ep->rx_skbuff[entry]->tail, pkt_len, 0);
+				eth_copy_and_sum(skb, ep->rx_skbuff[entry]->data, pkt_len, 0);
 				skb_put(skb, pkt_len);
 				pci_dma_sync_single_for_device(ep->pci_dev,
 							       ep->rx_ring[entry].bufaddr,
@@ -1308,7 +1308,7 @@ static int epic_rx(struct net_device *dev, int budget)
 			skb->dev = dev;			/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
 			ep->rx_ring[entry].bufaddr = pci_map_single(ep->pci_dev, 
-				skb->tail, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
+				skb->data, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
 			work_done++;
 		}
 		ep->rx_ring[entry].rxstatus = cpu_to_le32(DescOwn);

drivers/net/fealnx.c

@@ -1107,7 +1107,7 @@ static void allocate_rx_buffers(struct net_device *dev)
 
 		skb->dev = dev;	/* Mark as being used by this device. */
 		np->lack_rxbuf->skbuff = skb;
-		np->lack_rxbuf->buffer = pci_map_single(np->pci_dev, skb->tail,
+		np->lack_rxbuf->buffer = pci_map_single(np->pci_dev, skb->data,
 			np->rx_buf_sz, PCI_DMA_FROMDEVICE);
 		np->lack_rxbuf->status = RXOWN;
 		++np->really_rx_count;
@@ -1300,7 +1300,7 @@ static void init_ring(struct net_device *dev)
 		++np->really_rx_count;
 		np->rx_ring[i].skbuff = skb;
 		skb->dev = dev;	/* Mark as being used by this device. */
-		np->rx_ring[i].buffer = pci_map_single(np->pci_dev, skb->tail,
+		np->rx_ring[i].buffer = pci_map_single(np->pci_dev, skb->data,
 			np->rx_buf_sz, PCI_DMA_FROMDEVICE);
 		np->rx_ring[i].status = RXOWN;
 		np->rx_ring[i].control |= RXIC;
@@ -1737,11 +1737,11 @@ static int netdev_rx(struct net_device *dev)
 
 #if ! defined(__alpha__)
 				eth_copy_and_sum(skb, 
-					np->cur_rx->skbuff->tail, pkt_len, 0);
+					np->cur_rx->skbuff->data, pkt_len, 0);
 				skb_put(skb, pkt_len);
 #else
 				memcpy(skb_put(skb, pkt_len),
-					np->cur_rx->skbuff->tail, pkt_len);
+					np->cur_rx->skbuff->data, pkt_len);
 #endif
 				pci_dma_sync_single_for_device(np->pci_dev,
 							       np->cur_rx->buffer,

drivers/net/hamachi.c

@@ -1149,7 +1149,7 @@ static void hamachi_tx_timeout(struct net_device *dev)
 		skb->dev = dev;         /* Mark as being used by this device. */
 		skb_reserve(skb, 2); /* 16 byte align the IP header. */
                 hmp->rx_ring[i].addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
-			skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+			skb->data, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
 		hmp->rx_ring[i].status_n_length = cpu_to_le32(DescOwn | 
 			DescEndPacket | DescIntr | (hmp->rx_buf_sz - 2));
 	}
@@ -1210,7 +1210,7 @@ static void hamachi_init_ring(struct net_device *dev)
 		skb->dev = dev;         /* Mark as being used by this device. */
 		skb_reserve(skb, 2); /* 16 byte align the IP header. */
                 hmp->rx_ring[i].addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
-			skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+			skb->data, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
 		/* -2 because it doesn't REALLY have that first 2 bytes -KDU */
 		hmp->rx_ring[i].status_n_length = cpu_to_le32(DescOwn | 
 			DescEndPacket | DescIntr | (hmp->rx_buf_sz -2));
@@ -1509,7 +1509,7 @@ static int hamachi_rx(struct net_device *dev)
 					    desc->addr,
 					    hmp->rx_buf_sz,
 					    PCI_DMA_FROMDEVICE);
-		buf_addr = (u8 *) hmp->rx_skbuff[entry]->tail;
+		buf_addr = (u8 *) hmp->rx_skbuff[entry]->data;
 		frame_status = le32_to_cpu(get_unaligned((s32*)&(buf_addr[data_size - 12])));
 		if (hamachi_debug > 4)
 			printk(KERN_DEBUG "  hamachi_rx() status was %8.8x.\n",
@@ -1678,7 +1678,7 @@ static int hamachi_rx(struct net_device *dev)
 			skb->dev = dev;		/* Mark as being used by this device. */
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
                 	desc->addr = cpu_to_leXX(pci_map_single(hmp->pci_dev, 
-				skb->tail, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
+				skb->data, hmp->rx_buf_sz, PCI_DMA_FROMDEVICE));
 		}
 		desc->status_n_length = cpu_to_le32(hmp->rx_buf_sz);
 		if (entry >= RX_RING_SIZE-1)
@@ -1772,9 +1772,9 @@ static int hamachi_close(struct net_device *dev)
 				   readl(ioaddr + RxCurPtr) == (long)&hmp->rx_ring[i] ? '>' : ' ',
 				   i, hmp->rx_ring[i].status_n_length, hmp->rx_ring[i].addr);
 			if (hamachi_debug > 6) {
-				if (*(u8*)hmp->rx_skbuff[i]->tail != 0x69) {
+				if (*(u8*)hmp->rx_skbuff[i]->data != 0x69) {
 					u16 *addr = (u16 *)
-						hmp->rx_skbuff[i]->tail;
+						hmp->rx_skbuff[i]->data;
 					int j;
 
 					for (j = 0; j < 0x50; j++)

drivers/net/lance.c

@@ -862,7 +862,7 @@ lance_init_ring(struct net_device *dev, int gfp)
 		lp->rx_skbuff[i] = skb;
 		if (skb) {
 			skb->dev = dev;
-			rx_buff = skb->tail;
+			rx_buff = skb->data;
 		} else
 			rx_buff = kmalloc(PKT_BUF_SZ, GFP_DMA | gfp);
 		if (rx_buff == NULL)

drivers/net/lasi_82596.c

@@ -553,14 +553,14 @@ static inline void init_rx_bufs(struct net_device *dev)
 		if (skb == NULL)
 			panic("%s: alloc_skb() failed", __FILE__);
 		skb_reserve(skb, 2);
-		dma_addr = dma_map_single(lp->dev, skb->tail,PKT_BUF_SZ,
+		dma_addr = dma_map_single(lp->dev, skb->data,PKT_BUF_SZ,
 					  DMA_FROM_DEVICE);
 		skb->dev = dev;
 		rbd->v_next = rbd+1;
 		rbd->b_next = WSWAPrbd(virt_to_dma(lp,rbd+1));
 		rbd->b_addr = WSWAPrbd(virt_to_dma(lp,rbd));
 		rbd->skb = skb;
-		rbd->v_data = skb->tail;
+		rbd->v_data = skb->data;
 		rbd->b_data = WSWAPchar(dma_addr);
 		rbd->size = PKT_BUF_SZ;
 	}
@@ -783,8 +783,8 @@ static inline int i596_rx(struct net_device *dev)
 				rx_in_place = 1;
 				rbd->skb = newskb;
 				newskb->dev = dev;
-				dma_addr = dma_map_single(lp->dev, newskb->tail, PKT_BUF_SZ, DMA_FROM_DEVICE);
-				rbd->v_data = newskb->tail;
+				dma_addr = dma_map_single(lp->dev, newskb->data, PKT_BUF_SZ, DMA_FROM_DEVICE);
+				rbd->v_data = newskb->data;
 				rbd->b_data = WSWAPchar(dma_addr);
 				CHECK_WBACK_INV(rbd, sizeof(struct i596_rbd));
 			}

drivers/net/natsemi.c

@@ -1926,7 +1926,7 @@ static void refill_rx(struct net_device *dev)
 				break; /* Better luck next round. */
 			skb->dev = dev; /* Mark as being used by this device. */
 			np->rx_dma[entry] = pci_map_single(np->pci_dev,
-				skb->tail, buflen, PCI_DMA_FROMDEVICE);
+				skb->data, buflen, PCI_DMA_FROMDEVICE);
 			np->rx_ring[entry].addr = cpu_to_le32(np->rx_dma[entry]);
 		}
 		np->rx_ring[entry].cmd_status = cpu_to_le32(np->rx_buf_sz);
@@ -2280,7 +2280,7 @@ static void netdev_rx(struct net_device *dev)
 					buflen,
 					PCI_DMA_FROMDEVICE);
 				eth_copy_and_sum(skb,
-					np->rx_skbuff[entry]->tail, pkt_len, 0);
+					np->rx_skbuff[entry]->data, pkt_len, 0);
 				skb_put(skb, pkt_len);
 				pci_dma_sync_single_for_device(np->pci_dev,
 					np->rx_dma[entry],

drivers/net/ns83820.c

@@ -574,7 +574,7 @@ static inline int ns83820_add_rx_skb(struct ns83820 *dev, struct sk_buff *skb)
 
 	dev->rx_info.next_empty = (next_empty + 1) % NR_RX_DESC;
 	cmdsts = REAL_RX_BUF_SIZE | CMDSTS_INTR;
-	buf = pci_map_single(dev->pci_dev, skb->tail,
+	buf = pci_map_single(dev->pci_dev, skb->data,
 			     REAL_RX_BUF_SIZE, PCI_DMA_FROMDEVICE);
 	build_rx_desc(dev, sg, 0, buf, cmdsts, 0);
 	/* update link of previous rx */
@@ -604,7 +604,7 @@ static inline int rx_refill(struct net_device *ndev, int gfp)
 		if (unlikely(!skb))
 			break;
 
-		res = (long)skb->tail & 0xf;
+		res = (long)skb->data & 0xf;
 		res = 0x10 - res;
 		res &= 0xf;
 		skb_reserve(skb, res);

drivers/net/pcnet32.c

@@ -1602,7 +1602,7 @@ pcnet32_init_ring(struct net_device *dev)
 
 	rmb();
 	if (lp->rx_dma_addr[i] == 0)
-	    lp->rx_dma_addr[i] = pci_map_single(lp->pci_dev, rx_skbuff->tail,
+	    lp->rx_dma_addr[i] = pci_map_single(lp->pci_dev, rx_skbuff->data,
 		    PKT_BUF_SZ-2, PCI_DMA_FROMDEVICE);
 	lp->rx_ring[i].base = (u32)le32_to_cpu(lp->rx_dma_addr[i]);
 	lp->rx_ring[i].buf_length = le16_to_cpu(2-PKT_BUF_SZ);
@@ -1983,7 +1983,7 @@ pcnet32_rx(struct net_device *dev)
 			lp->rx_skbuff[entry] = newskb;
 			newskb->dev = dev;
 			lp->rx_dma_addr[entry] =
-			    pci_map_single(lp->pci_dev, newskb->tail,
+			    pci_map_single(lp->pci_dev, newskb->data,
 				    PKT_BUF_SZ-2, PCI_DMA_FROMDEVICE);
 			lp->rx_ring[entry].base = le32_to_cpu(lp->rx_dma_addr[entry]);
 			rx_in_place = 1;
@@ -2020,7 +2020,7 @@ pcnet32_rx(struct net_device *dev)
 						PKT_BUF_SZ-2,
 						PCI_DMA_FROMDEVICE);
 		    eth_copy_and_sum(skb,
-			    (unsigned char *)(lp->rx_skbuff[entry]->tail),
+			    (unsigned char *)(lp->rx_skbuff[entry]->data),
 			    pkt_len,0);
 		    pci_dma_sync_single_for_device(lp->pci_dev,
 						   lp->rx_dma_addr[entry],

drivers/net/r8169.c

@@ -1876,7 +1876,7 @@ static int rtl8169_alloc_rx_skb(struct pci_dev *pdev, struct sk_buff **sk_buff,
 	skb_reserve(skb, NET_IP_ALIGN);
 	*sk_buff = skb;
 
-	mapping = pci_map_single(pdev, skb->tail, rx_buf_sz,
+	mapping = pci_map_single(pdev, skb->data, rx_buf_sz,
 				 PCI_DMA_FROMDEVICE);
 
 	rtl8169_map_to_asic(desc, mapping, rx_buf_sz);
@@ -2336,7 +2336,7 @@ static inline int rtl8169_try_rx_copy(struct sk_buff **sk_buff, int pkt_size,
 		skb = dev_alloc_skb(pkt_size + NET_IP_ALIGN);
 		if (skb) {
 			skb_reserve(skb, NET_IP_ALIGN);
-			eth_copy_and_sum(skb, sk_buff[0]->tail, pkt_size, 0);
+			eth_copy_and_sum(skb, sk_buff[0]->data, pkt_size, 0);
 			*sk_buff = skb;
 			rtl8169_mark_to_asic(desc, rx_buf_sz);
 			ret = 0;