From 59ae1d127ac0ae404baf414c434ba2651b793f46 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Fri, 16 Jun 2017 14:29:20 +0200
Subject: 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>
---
 drivers/isdn/i4l/isdn_ppp.c  | 3 +--
 drivers/isdn/i4l/isdn_tty.c  | 2 +-
 drivers/isdn/i4l/isdn_v110.c | 6 +++---
 3 files changed, 5 insertions(+), 6 deletions(-)

(limited to 'drivers/isdn/i4l')

diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c
index 8aa158a09180..9ce23cf3d7d2 100644
--- a/drivers/isdn/i4l/isdn_ppp.c
+++ b/drivers/isdn/i4l/isdn_ppp.c
@@ -2258,8 +2258,7 @@ static void isdn_ppp_ccp_xmit_reset(struct ippp_struct *is, int proto,
 
 	/* Now stuff remaining bytes */
 	if (len) {
-		p = skb_put(skb, len);
-		memcpy(p, data, len);
+		p = skb_put_data(skb, data, len);
 	}
 
 	/* skb is now ready for xmit */
diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index ddd8207e4e54..d30130c8d0f3 100644
--- a/drivers/isdn/i4l/isdn_tty.c
+++ b/drivers/isdn/i4l/isdn_tty.c
@@ -474,7 +474,7 @@ isdn_tty_senddown(modem_info *info)
 		return;
 	}
 	skb_reserve(skb, skb_res);
-	memcpy(skb_put(skb, buflen), info->port.xmit_buf, buflen);
+	skb_put_data(skb, info->port.xmit_buf, buflen);
 	info->xmit_count = 0;
 #ifdef CONFIG_ISDN_AUDIO
 	if (info->vonline & 2) {
diff --git a/drivers/isdn/i4l/isdn_v110.c b/drivers/isdn/i4l/isdn_v110.c
index 52827a80c51f..8b74ce412524 100644
--- a/drivers/isdn/i4l/isdn_v110.c
+++ b/drivers/isdn/i4l/isdn_v110.c
@@ -421,7 +421,7 @@ isdn_v110_sync(isdn_v110_stream *v)
 	}
 	if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
 		skb_reserve(skb, v->skbres);
-		memcpy(skb_put(skb, v->framelen), v->OfflineFrame, v->framelen);
+		skb_put_data(skb, v->OfflineFrame, v->framelen);
 	}
 	return skb;
 }
@@ -441,7 +441,7 @@ isdn_v110_idle(isdn_v110_stream *v)
 	}
 	if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
 		skb_reserve(skb, v->skbres);
-		memcpy(skb_put(skb, v->framelen), v->OnlineFrame, v->framelen);
+		skb_put_data(skb, v->OnlineFrame, v->framelen);
 	}
 	return skb;
 }
@@ -486,7 +486,7 @@ isdn_v110_encode(isdn_v110_stream *v, struct sk_buff *skb)
 	}
 	skb_reserve(nskb, v->skbres + sizeof(int));
 	if (skb->len == 0) {
-		memcpy(skb_put(nskb, v->framelen), v->OnlineFrame, v->framelen);
+		skb_put_data(nskb, v->OnlineFrame, v->framelen);
 		*((int *)skb_push(nskb, sizeof(int))) = 0;
 		return nskb;
 	}
-- 
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