net: add skb frag size accessors

To ease skb->truesize sanitization, its better to be able to localize
all references to skb frags size.

Define accessors : skb_frag_size() to fetch frag size, and
skb_frag_size_{set|add|sub}() to manipulate it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

71 files changed, 278 insertions, 273 deletions

diff --git a/drivers/atm/eni.c b/drivers/atm/eni.c
index f7ca4c13d61..956e9accb05 100644
--- a/drivers/atm/eni.c
+++ b/drivers/atm/eni.c
@@ -1136,7 +1136,7 @@ DPRINTK("doing direct send\n"); /* @@@ well, this doesn't work anyway */
 				put_dma(tx->index,eni_dev->dma,&j,(unsigned long)
 				    skb_frag_page(&skb_shinfo(skb)->frags[i]) +
 					skb_shinfo(skb)->frags[i].page_offset,
-				    skb_shinfo(skb)->frags[i].size);
+				    skb_frag_size(&skb_shinfo(skb)->frags[i]));
 	}
 	if (skb->len & 3)
 		put_dma(tx->index,eni_dev->dma,&j,zeroes,4-(skb->len & 3));
diff --git a/drivers/infiniband/hw/amso1100/c2.c b/drivers/infiniband/hw/amso1100/c2.c
index 6e85a75289e..5ce7b9e8bff 100644
--- a/drivers/infiniband/hw/amso1100/c2.c
+++ b/drivers/infiniband/hw/amso1100/c2.c
@@ -800,8 +800,8 @@ static int c2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 	/* Loop thru additional data fragments and queue them */
 	if (skb_shinfo(skb)->nr_frags) {
 		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-			maplen = frag->size;
+			const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+			maplen = skb_frag_size(frag);
 			mapaddr = skb_frag_dma_map(&c2dev->pcidev->dev, frag,
 						   0, maplen, DMA_TO_DEVICE);
 			elem = elem->next;
diff --git a/drivers/infiniband/hw/nes/nes_nic.c b/drivers/infiniband/hw/nes/nes_nic.c
index 7cb7f292dfd..47b2ee4c01e 100644
--- a/drivers/infiniband/hw/nes/nes_nic.c
+++ b/drivers/infiniband/hw/nes/nes_nic.c
@@ -444,10 +444,10 @@ static int nes_nic_send(struct sk_buff *skb, struct net_device *netdev)
 			skb_frag_t *frag =
 				&skb_shinfo(skb)->frags[skb_fragment_index];
 			bus_address = skb_frag_dma_map(&nesdev->pcidev->dev,
-						       frag, 0, frag->size,
+						       frag, 0, skb_frag_size(frag),
 						       DMA_TO_DEVICE);
 			wqe_fragment_length[wqe_fragment_index] =
-					cpu_to_le16(skb_shinfo(skb)->frags[skb_fragment_index].size);
+					cpu_to_le16(skb_frag_size(&skb_shinfo(skb)->frags[skb_fragment_index]));
 			set_wqe_64bit_value(nic_sqe->wqe_words, NES_NIC_SQ_WQE_FRAG0_LOW_IDX+(2*wqe_fragment_index),
 				bus_address);
 			wqe_fragment_index++;
@@ -565,7 +565,7 @@ tso_sq_no_longer_full:
 					&skb_shinfo(skb)->frags[tso_frag_count];
 				tso_bus_address[tso_frag_count] =
 					skb_frag_dma_map(&nesdev->pcidev->dev,
-							 frag, 0, frag->size,
+							 frag, 0, skb_frag_size(frag),
 							 DMA_TO_DEVICE);
 			}
 
@@ -637,11 +637,11 @@ tso_sq_no_longer_full:
 				}
 				while (wqe_fragment_index < 5) {
 					wqe_fragment_length[wqe_fragment_index] =
-							cpu_to_le16(skb_shinfo(skb)->frags[tso_frag_index].size);
+							cpu_to_le16(skb_frag_size(&skb_shinfo(skb)->frags[tso_frag_index]));
 					set_wqe_64bit_value(nic_sqe->wqe_words, NES_NIC_SQ_WQE_FRAG0_LOW_IDX+(2*wqe_fragment_index),
 						(u64)tso_bus_address[tso_frag_index]);
 					wqe_fragment_index++;
-					tso_wqe_length += skb_shinfo(skb)->frags[tso_frag_index++].size;
+					tso_wqe_length += skb_frag_size(&skb_shinfo(skb)->frags[tso_frag_index++]);
 					if (wqe_fragment_index < 5)
 						wqe_fragment_length[wqe_fragment_index] = 0;
 					if (tso_frag_index == tso_frag_count)
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 67a477be237..c74548a586e 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -543,7 +543,7 @@ static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
 		} else {
 			size = min(length, (unsigned) PAGE_SIZE);
 
-			frag->size = size;
+			skb_frag_size_set(frag, size);
 			skb->data_len += size;
 			skb->truesize += size;
 			skb->len += size;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 00435be4a44..2b060f45bec 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -117,7 +117,7 @@ static void ipoib_ud_skb_put_frags(struct ipoib_dev_priv *priv,
 
 		size = length - IPOIB_UD_HEAD_SIZE;
 
-		frag->size     = size;
+		skb_frag_size_set(frag, size);
 		skb->data_len += size;
 		skb->truesize += size;
 	} else
@@ -322,10 +322,10 @@ static int ipoib_dma_map_tx(struct ib_device *ca,
 		off = 0;
 
 	for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
-		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 		mapping[i + off] = ib_dma_map_page(ca,
 						 skb_frag_page(frag),
-						 frag->page_offset, frag->size,
+						 frag->page_offset, skb_frag_size(frag),
 						 DMA_TO_DEVICE);
 		if (unlikely(ib_dma_mapping_error(ca, mapping[i + off])))
 			goto partial_error;
@@ -334,8 +334,9 @@ static int ipoib_dma_map_tx(struct ib_device *ca,
 
 partial_error:
 	for (; i > 0; --i) {
-		skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
-		ib_dma_unmap_page(ca, mapping[i - !off], frag->size, DMA_TO_DEVICE);
+		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
+
+		ib_dma_unmap_page(ca, mapping[i - !off], skb_frag_size(frag), DMA_TO_DEVICE);
 	}
 
 	if (off)
@@ -359,8 +360,9 @@ static void ipoib_dma_unmap_tx(struct ib_device *ca,
 		off = 0;
 
 	for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
-		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-		ib_dma_unmap_page(ca, mapping[i + off], frag->size,
+		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+		ib_dma_unmap_page(ca, mapping[i + off], skb_frag_size(frag),
 				  DMA_TO_DEVICE);
 	}
 }
@@ -510,7 +512,7 @@ static inline int post_send(struct ipoib_dev_priv *priv,
 
 	for (i = 0; i < nr_frags; ++i) {
 		priv->tx_sge[i + off].addr = mapping[i + off];
-		priv->tx_sge[i + off].length = frags[i].size;
+		priv->tx_sge[i + off].length = skb_frag_size(&frags[i]);
 	}
 	priv->tx_wr.num_sge	     = nr_frags + off;
 	priv->tx_wr.wr_id 	     = wr_id;
diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c
index 9ca45dcba75..b42c06baba8 100644
--- a/drivers/net/ethernet/3com/3c59x.c
+++ b/drivers/net/ethernet/3com/3c59x.c
@@ -2182,12 +2182,12 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev)
 					cpu_to_le32(pci_map_single(
 						VORTEX_PCI(vp),
 						(void *)skb_frag_address(frag),
-						frag->size, PCI_DMA_TODEVICE));
+						skb_frag_size(frag), PCI_DMA_TODEVICE));
 
 			if (i == skb_shinfo(skb)->nr_frags-1)
-					vp->tx_ring[entry].frag[i+1].length = cpu_to_le32(frag->size|LAST_FRAG);
+					vp->tx_ring[entry].frag[i+1].length = cpu_to_le32(skb_frag_size(frag)|LAST_FRAG);
 			else
-					vp->tx_ring[entry].frag[i+1].length = cpu_to_le32(frag->size);
+					vp->tx_ring[entry].frag[i+1].length = cpu_to_le32(skb_frag_size(frag));
 		}
 	}
 #else
diff --git a/drivers/net/ethernet/3com/typhoon.c b/drivers/net/ethernet/3com/typhoon.c
index 11f8858c786..20ea07508ac 100644
--- a/drivers/net/ethernet/3com/typhoon.c
+++ b/drivers/net/ethernet/3com/typhoon.c
@@ -810,15 +810,15 @@ typhoon_start_tx(struct sk_buff *skb, struct net_device *dev)
 		txd->frag.addrHi = 0;
 		first_txd->numDesc++;
 
-		for(i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+			const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 			void *frag_addr;
 
 			txd = (struct tx_desc *) (txRing->ringBase +
 						txRing->lastWrite);
 			typhoon_inc_tx_index(&txRing->lastWrite, 1);
 
-			len = frag->size;
+			len = skb_frag_size(frag);
 			frag_addr = skb_frag_address(frag);
 			skb_dma = pci_map_single(tp->tx_pdev, frag_addr, len,
 					 PCI_DMA_TODEVICE);
diff --git a/drivers/net/ethernet/adaptec/starfire.c b/drivers/net/ethernet/adaptec/starfire.c
index d6b01559856..6d9f6911000 100644
--- a/drivers/net/ethernet/adaptec/starfire.c
+++ b/drivers/net/ethernet/adaptec/starfire.c
@@ -1256,12 +1256,12 @@ static netdev_tx_t start_tx(struct sk_buff *skb, struct net_device *dev)
 			np->tx_info[entry].mapping =
 				pci_map_single(np->pci_dev, skb->data, skb_first_frag_len(skb), PCI_DMA_TODEVICE);
 		} else {
-			skb_frag_t *this_frag = &skb_shinfo(skb)->frags[i - 1];
-			status |= this_frag->size;
+			const skb_frag_t *this_frag = &skb_shinfo(skb)->frags[i - 1];
+			status |= skb_frag_size(this_frag);
 			np->tx_info[entry].mapping =
 				pci_map_single(np->pci_dev,
 					       skb_frag_address(this_frag),
-					       this_frag->size,
+					       skb_frag_size(this_frag),
 					       PCI_DMA_TODEVICE);
 		}
 
@@ -1378,7 +1378,7 @@ static irqreturn_t intr_handler(int irq, void *dev_instance)
 					for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 						pci_unmap_single(np->pci_dev,
 								 np->tx_info[entry].mapping,
-								 skb_shinfo(skb)->frags[i].size,
+								 skb_frag_size(&skb_shinfo(skb)->frags[i]),
 								 PCI_DMA_TODEVICE);
 						np->dirty_tx++;
 						entry++;
diff --git a/drivers/net/ethernet/aeroflex/greth.c b/drivers/net/ethernet/aeroflex/greth.c
index 6715bf54f04..442fefa4f2c 100644
--- a/drivers/net/ethernet/aeroflex/greth.c
+++ b/drivers/net/ethernet/aeroflex/greth.c
@@ -198,7 +198,7 @@ static void greth_clean_rings(struct greth_private *greth)
 
 				dma_unmap_page(greth->dev,
 					       greth_read_bd(&tx_bdp->addr),
-					       frag->size,
+					       skb_frag_size(frag),
 					       DMA_TO_DEVICE);
 
 				greth->tx_last = NEXT_TX(greth->tx_last);
@@ -517,7 +517,7 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
 		status = GRETH_BD_EN;
 		if (skb->ip_summed == CHECKSUM_PARTIAL)
 			status |= GRETH_TXBD_CSALL;
-		status |= frag->size & GRETH_BD_LEN;
+		status |= skb_frag_size(frag) & GRETH_BD_LEN;
 
 		/* Wrap around descriptor ring */
 		if (curr_tx == GRETH_TXBD_NUM_MASK)
@@ -531,7 +531,7 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
 
 		greth_write_bd(&bdp->stat, status);
 
-		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, frag->size,
+		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
 					    DMA_TO_DEVICE);
 
 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
@@ -713,7 +713,7 @@ static void greth_clean_tx_gbit(struct net_device *dev)
 
 			dma_unmap_page(greth->dev,
 				       greth_read_bd(&bdp->addr),
-				       frag->size,
+				       skb_frag_size(frag),
 				       DMA_TO_DEVICE);
 
 			greth->tx_last = NEXT_TX(greth->tx_last);
diff --git a/drivers/net/ethernet/alteon/acenic.c b/drivers/net/ethernet/alteon/acenic.c
index b1a4e820443..f872748ab4e 100644
--- a/drivers/net/ethernet/alteon/acenic.c
+++ b/drivers/net/ethernet/alteon/acenic.c
@@ -2478,18 +2478,18 @@ restart:
 		idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);
 
 		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+			const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 			struct tx_ring_info *info;
 
-			len += frag->size;
+			len += skb_frag_size(frag);
 			info = ap->skb->tx_skbuff + idx;
 			desc = ap->tx_ring + idx;
 
 			mapping = skb_frag_dma_map(&ap->pdev->dev, frag, 0,
-						   frag->size,
+						   skb_frag_size(frag),
 						   DMA_TO_DEVICE);
 
-			flagsize = (frag->size << 16);
+			flagsize = skb_frag_size(frag) << 16;
 			if (skb->ip_summed == CHECKSUM_PARTIAL)
 				flagsize |= BD_FLG_TCP_UDP_SUM;
 			idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);
@@ -2508,7 +2508,7 @@ restart:
 				info->skb = NULL;
 			}
 			dma_unmap_addr_set(info, mapping, mapping);
-			dma_unmap_len_set(info, maplen, frag->size);
+			dma_unmap_len_set(info, maplen, skb_frag_size(frag));
 			ace_load_tx_bd(ap, desc, mapping, flagsize, vlan_tag);
 		}
 	}
diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
index 12a0b30319d..02c7ed8d9ec 100644
--- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
@@ -2179,7 +2179,7 @@ static void atl1c_tx_map(struct atl1c_adapter *adapter,
 		memcpy(use_tpd, tpd, sizeof(struct atl1c_tpd_desc));
 
 		buffer_info = atl1c_get_tx_buffer(adapter, use_tpd);
-		buffer_info->length = frag->size;
+		buffer_info->length = skb_frag_size(frag);
 		buffer_info->dma = skb_frag_dma_map(&adapter->pdev->dev,
 						    frag, 0,
 						    buffer_info->length,
diff --git a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
index 97c45a4b855..95483bcac1d 100644
--- a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
+++ b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
@@ -1593,7 +1593,7 @@ static u16 atl1e_cal_tdp_req(const struct sk_buff *skb)
 	u16 proto_hdr_len = 0;
 
 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-		fg_size = skb_shinfo(skb)->frags[i].size;
+		fg_size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
 		tpd_req += ((fg_size + MAX_TX_BUF_LEN - 1) >> MAX_TX_BUF_SHIFT);
 	}
 
@@ -1744,12 +1744,12 @@ static void atl1e_tx_map(struct atl1e_adapter *adapter,
 	}
 
 	for (f = 0; f < nr_frags; f++) {
-		struct skb_frag_struct *frag;
+		const struct skb_frag_struct *frag;
 		u16 i;
 		u16 seg_num;
 
 		frag = &skb_shinfo(skb)->frags[f];
-		buf_len = frag->size;
+		buf_len = skb_frag_size(frag);
 
 		seg_num = (buf_len + MAX_TX_BUF_LEN - 1) / MAX_TX_BUF_LEN;
 		for (i = 0; i < seg_num; i++) {
diff --git a/drivers/net/ethernet/atheros/atlx/atl1.c b/drivers/net/ethernet/atheros/atlx/atl1.c
index 7381a49fefb..0405261efb5 100644
--- a/drivers/net/ethernet/atheros/atlx/atl1.c
+++ b/drivers/net/ethernet/atheros/atlx/atl1.c
@@ -2267,11 +2267,11 @@ static void atl1_tx_map(struct atl1_adapter *adapter, struct sk_buff *skb,
 	}
 
 	for (f = 0; f < nr_frags; f++) {
-		struct skb_frag_struct *frag;
+		const struct skb_frag_struct *frag;
 		u16 i, nseg;
 
 		frag = &skb_shinfo(skb)->frags[f];
-		buf_len = frag->size;
+		buf_len = skb_frag_size(frag);
 
 		nseg = (buf_len + ATL1_MAX_TX_BUF_LEN - 1) /
 			ATL1_MAX_TX_BUF_LEN;
@@ -2356,7 +2356,6 @@ static netdev_tx_t atl1_xmit_frame(struct sk_buff *skb,
 	int count = 1;
 	int ret_val;
 	struct tx_packet_desc *ptpd;
-	u16 frag_size;
 	u16 vlan_tag;
 	unsigned int nr_frags = 0;
 	unsigned int mss = 0;
@@ -2372,10 +2371,9 @@ static netdev_tx_t atl1_xmit_frame(struct sk_buff *skb,
 
 	nr_frags = skb_shinfo(skb)->nr_frags;
 	for (f = 0; f < nr_frags; f++) {
-		frag_size = skb_shinfo(skb)->frags[f].size;
-		if (frag_size)
-			count += (frag_size + ATL1_MAX_TX_BUF_LEN - 1) /
-				ATL1_MAX_TX_BUF_LEN;
+		unsigned int f_size = skb_frag_size(&skb_shinfo(skb)->frags[f]);
+		count += (f_size + ATL1_MAX_TX_BUF_LEN - 1) /
+			 ATL1_MAX_TX_BUF_LEN;
 	}
 
 	mss = skb_shinfo(skb)->gso_size;
diff --git a/drivers/net/ethernet/broadcom/bnx2.c b/drivers/net/ethernet/broadcom/bnx2.c
index 6ff7636e73a..965c7235804 100644
--- a/drivers/net/ethernet/broadcom/bnx2.c
+++ b/drivers/net/ethernet/broadcom/bnx2.c
@@ -2871,7 +2871,7 @@ bnx2_tx_int(struct bnx2 *bp, struct bnx2_napi *bnapi, int budget)
 				dma_unmap_addr(
 					&txr->tx_buf_ring[TX_RING_IDX(sw_cons)],
 					mapping),
-				skb_shinfo(skb)->frags[i].size,
+				skb_frag_size(&skb_shinfo(skb)->frags[i]),
 				PCI_DMA_TODEVICE);
 		}
 
@@ -3049,7 +3049,7 @@ bnx2_rx_skb(struct bnx2 *bp, struct bnx2_rx_ring_info *rxr, struct sk_buff *skb,
 				} else {
 					skb_frag_t *frag =
 						&skb_shinfo(skb)->frags[i - 1];
-					frag->size -= tail;
+					skb_frag_size_sub(frag, tail);
 					skb->data_len -= tail;
 				}
 				return 0;
@@ -5395,7 +5395,7 @@ bnx2_free_tx_skbs(struct bnx2 *bp)
 				tx_buf = &txr->tx_buf_ring[TX_RING_IDX(j)];
 				dma_unmap_page(&bp->pdev->dev,
 					dma_unmap_addr(tx_buf, mapping),
-					skb_shinfo(skb)->frags[k].size,
+					skb_frag_size(&skb_shinfo(skb)->frags[k]),
 					PCI_DMA_TODEVICE);
 			}