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>

4 files changed, 18 insertions, 16 deletions

diff --git a/drivers/infiniband/hw/amso1100/c2.c b/drivers/infiniband/hw/amso1100/c2.c
index 6e85a75289e8..5ce7b9e8bff6 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 7cb7f292dfd1..47b2ee4c01e2 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 67a477be237e..c74548a586ea 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 00435be4a44b..2b060f45bec3 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;