networking: introduce and use skb_put_data()

A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 6 deletions

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 1fb92e870040..08338f27c82c 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5147,12 +5147,11 @@ static inline int qeth_create_skb_frag(struct qeth_qdio_buffer *qethbuffer,
 
 		skb_reserve(*pskb, ETH_HLEN);
 		if (data_len <= QETH_RX_PULL_LEN) {
-			memcpy(skb_put(*pskb, data_len), element->addr + offset,
-				data_len);
+			skb_put_data(*pskb, element->addr + offset, data_len);
 		} else {
 			get_page(page);
-			memcpy(skb_put(*pskb, QETH_RX_PULL_LEN),
-			       element->addr + offset, QETH_RX_PULL_LEN);
+			skb_put_data(*pskb, element->addr + offset,
+				     QETH_RX_PULL_LEN);
 			skb_fill_page_desc(*pskb, *pfrag, page,
 				offset + QETH_RX_PULL_LEN,
 				data_len - QETH_RX_PULL_LEN);
@@ -5248,8 +5247,7 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card,
 				    &skb, offset, &frag, data_len))
 					goto no_mem;
 			} else {
-				memcpy(skb_put(skb, data_len), data_ptr,
-					data_len);
+				skb_put_data(skb, data_ptr, data_len);
 			}
 		}
 		skb_len -= data_len;