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>

2 files changed, 16 insertions, 17 deletions

diff --git a/drivers/isdn/hysdn/hycapi.c b/drivers/isdn/hysdn/hycapi.c
index 93bae94314a6..87119b517508 100644
--- a/drivers/isdn/hysdn/hycapi.c
+++ b/drivers/isdn/hysdn/hycapi.c
@@ -171,16 +171,16 @@ hycapi_register_internal(struct capi_ctr *ctrl, __u16 appl,
 		       card->myid);
 		return;
 	}
-	memcpy(skb_put(skb, sizeof(__u16)), &len, sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &appl, sizeof(__u16));
+	skb_put_data(skb, &len, sizeof(__u16));
+	skb_put_data(skb, &appl, sizeof(__u16));
 	memcpy(skb_put(skb, sizeof(__u8)), &_command, sizeof(_command));
 	memcpy(skb_put(skb, sizeof(__u8)), &_subcommand, sizeof(_subcommand));
-	memcpy(skb_put(skb, sizeof(__u16)), &MessageNumber, sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &MessageBufferSize, sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &(rp->level3cnt), sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &(rp->datablkcnt), sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &(rp->datablklen), sizeof(__u16));
-	memcpy(skb_put(skb, slen), ExtFeatureDefaults, slen);
+	skb_put_data(skb, &MessageNumber, sizeof(__u16));
+	skb_put_data(skb, &MessageBufferSize, sizeof(__u16));
+	skb_put_data(skb, &(rp->level3cnt), sizeof(__u16));
+	skb_put_data(skb, &(rp->datablkcnt), sizeof(__u16));
+	skb_put_data(skb, &(rp->datablklen), sizeof(__u16));
+	skb_put_data(skb, ExtFeatureDefaults, slen);
 	hycapi_applications[appl - 1].ctrl_mask |= (1 << (ctrl->cnr - 1));
 	hycapi_send_message(ctrl, skb);
 }
@@ -279,11 +279,11 @@ static void hycapi_release_internal(struct capi_ctr *ctrl, __u16 appl)
 		       card->myid);
 		return;
 	}
-	memcpy(skb_put(skb, sizeof(__u16)), &len, sizeof(__u16));
-	memcpy(skb_put(skb, sizeof(__u16)), &appl, sizeof(__u16));
+	skb_put_data(skb, &len, sizeof(__u16));
+	skb_put_data(skb, &appl, sizeof(__u16));
 	memcpy(skb_put(skb, sizeof(__u8)), &_command, sizeof(_command));
 	memcpy(skb_put(skb, sizeof(__u8)), &_subcommand, sizeof(_subcommand));
-	memcpy(skb_put(skb, sizeof(__u16)), &MessageNumber, sizeof(__u16));
+	skb_put_data(skb, &MessageNumber, sizeof(__u16));
 	hycapi_send_message(ctrl, skb);
 	hycapi_applications[appl - 1].ctrl_mask &= ~(1 << (ctrl->cnr - 1));
 }
@@ -557,10 +557,9 @@ hycapi_rx_capipkt(hysdn_card *card, unsigned char *buf, unsigned short len)
 			       card->myid);
 			return;
 		}
-		memcpy(skb_put(skb, MsgLen), buf, MsgLen);
-		memcpy(skb_put(skb, 2 * sizeof(__u32)), CP64, 2 * sizeof(__u32));
-		memcpy(skb_put(skb, len - MsgLen), buf + MsgLen,
-		       len - MsgLen);
+		skb_put_data(skb, buf, MsgLen);
+		skb_put_data(skb, CP64, 2 * sizeof(__u32));
+		skb_put_data(skb, buf + MsgLen, len - MsgLen);
 		CAPIMSG_SETLEN(skb->data, 30);
 	} else {
 		if (!(skb = alloc_skb(len, GFP_ATOMIC))) {
@@ -568,7 +567,7 @@ hycapi_rx_capipkt(hysdn_card *card, unsigned char *buf, unsigned short len)
 			       card->myid);
 			return;
 		}
-		memcpy(skb_put(skb, len), buf, len);
+		skb_put_data(skb, buf, len);
 	}
 	switch (CAPIMSG_CMD(skb->data))
 	{
diff --git a/drivers/isdn/hysdn/hysdn_net.c b/drivers/isdn/hysdn/hysdn_net.c
index b93a4e9a8d34..8e9c34f33d86 100644
--- a/drivers/isdn/hysdn/hysdn_net.c
+++ b/drivers/isdn/hysdn/hysdn_net.c
@@ -201,7 +201,7 @@ hysdn_rx_netpkt(hysdn_card *card, unsigned char *buf, unsigned short len)
 		return;
 	}
 	/* copy the data */
-	memcpy(skb_put(skb, len), buf, len);
+	skb_put_data(skb, buf, len);
 
 	/* determine the used protocol */
 	skb->protocol = eth_type_trans(skb, dev);