Merge branch 'pskb_put'

Mathias Krause says:

====================
move pskb_put (was: IPsec improvements)

This series moves pskb_put() to the core code, making the code
duplication in caif obsolete (patches 1 and 2).
Patch 3 fixes a few kernel-doc issues.

v2 of this series does no longer contain the skb_cow_data() patch and
therefore no performance improvements for IPsec. The change is still
under discussion, but otherwise independent from the above changes.

Please apply!

v2:
- kernel-doc fixes for pskb_put, as noticed by Ben
- dropped skb_cow_data patch as it's still discussed
- added a kernel-doc fixes patch (patch 3)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/skbuff.h

@@ -1357,7 +1357,7 @@ static inline void __skb_fill_page_desc(struct sk_buff *skb, int i,
  * @size: the length of the data
  *
  * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
- * @skb to point to &size bytes at offset @off within @page. In
+ * @skb to point to @size bytes at offset @off within @page. In
  * addition updates @skb such that @i is the last fragment.
  *
  * Does not take any additional reference on the fragment.
@@ -1417,6 +1417,7 @@ static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
 /*
  *	Add data to an sk_buff
  */
+unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len);
 unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
 static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
 {

include/net/esp.h

@@ -3,8 +3,6 @@
 
 #include <linux/skbuff.h>
 
-void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len);
-
 struct ip_esp_hdr;
 
 static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb)

net/caif/cfpkt_skbuff.c

@@ -203,20 +203,10 @@ int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len)
 			PKT_ERROR(pkt, "cow failed\n");
 			return -EPROTO;
 		}
-		/*
-		 * Is the SKB non-linear after skb_cow_data()? If so, we are
-		 * going to add data to the last SKB, so we need to adjust
-		 * lengths of the top SKB.
-		 */
-		if (lastskb != skb) {
-			pr_warn("Packet is non-linear\n");
-			skb->len += len;
-			skb->data_len += len;
-		}
 	}
 
 	/* All set to put the last SKB and optionally write data there. */
-	to = skb_put(lastskb, len);
+	to = pskb_put(skb, lastskb, len);
 	if (likely(data))
 		memcpy(to, data, len);
 	return 0;

net/core/skbuff.c

@@ -1051,8 +1051,8 @@ EXPORT_SYMBOL(__pskb_copy);
  *	@ntail: room to add at tail
  *	@gfp_mask: allocation priority
  *
- *	Expands (or creates identical copy, if &nhead and &ntail are zero)
- *	header of skb. &sk_buff itself is not changed. &sk_buff MUST have
+ *	Expands (or creates identical copy, if @nhead and @ntail are zero)
+ *	header of @skb. &sk_buff itself is not changed. &sk_buff MUST have
  *	reference count of 1. Returns zero in the case of success or error,
  *	if expansion failed. In the last case, &sk_buff is not changed.
  *
@@ -1263,6 +1263,29 @@ free_skb:
 }
 EXPORT_SYMBOL(skb_pad);
 
+/**
+ *	pskb_put - add data to the tail of a potentially fragmented buffer
+ *	@skb: start of the buffer to use
+ *	@tail: tail fragment of the buffer to use
+ *	@len: amount of data to add
+ *
+ *	This function extends the used data area of the potentially
+ *	fragmented buffer. @tail must be the last fragment of @skb -- or
+ *	@skb itself. If this would exceed the total buffer size the kernel
+ *	will panic. A pointer to the first byte of the extra data is
+ *	returned.
+ */
+
+unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len)
+{
+	if (tail != skb) {
+		skb->data_len += len;
+		skb->len += len;
+	}
+	return skb_put(tail, len);
+}
+EXPORT_SYMBOL_GPL(pskb_put);
+
 /**
  *	skb_put - add data to a buffer
  *	@skb: buffer to use
@@ -2540,14 +2563,14 @@ EXPORT_SYMBOL(skb_prepare_seq_read);
  * @data: destination pointer for data to be returned
  * @st: state variable
  *
- * Reads a block of skb data at &consumed relative to the
+ * Reads a block of skb data at @consumed relative to the
  * lower offset specified to skb_prepare_seq_read(). Assigns
- * the head of the data block to &data and returns the length
+ * the head of the data block to @data and returns the length
  * of the block or 0 if the end of the skb data or the upper
  * offset has been reached.
  *
  * The caller is not required to consume all of the data
- * returned, i.e. &consumed is typically set to the number
+ * returned, i.e. @consumed is typically set to the number
  * of bytes already consumed and the next call to
  * skb_seq_read() will return the remaining part of the block.
  *

net/xfrm/xfrm_algo.c

@@ -802,17 +802,4 @@ int xfrm_count_pfkey_enc_supported(void)
 }
 EXPORT_SYMBOL_GPL(xfrm_count_pfkey_enc_supported);
 
-#if defined(CONFIG_INET_ESP) || defined(CONFIG_INET_ESP_MODULE) || defined(CONFIG_INET6_ESP) || defined(CONFIG_INET6_ESP_MODULE)
-
-void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len)
-{
-	if (tail != skb) {
-		skb->data_len += len;
-		skb->len += len;
-	}
-	return skb_put(tail, len);
-}
-EXPORT_SYMBOL_GPL(pskb_put);
-#endif
-
 MODULE_LICENSE("GPL");