Commit a8605c60 authored by Ian Campbell's avatar Ian Campbell Committed by David S. Miller
Browse files

net: add opaque struct around skb frag page 



I've split this bit out of the skb frag destructor patch since it helps enforce
the use of the fragment API.

Signed-off-by: default avatarIan Campbell <ian.campbell@citrix.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6a39a16a

include/linux/skbuff.h

+6 −4
Original line number Diff line number Diff line
@@ -140,7 +140,9 @@ struct sk_buff; 
typedef struct skb_frag_struct skb_frag_t;



struct skb_frag_struct {

	struct page *page;

	struct {

		struct page *p;

	} page;

#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)

	__u32 page_offset;

	__u32 size;
@@ -1175,7 +1177,7 @@ static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, 
{

	skb_frag_t *frag = &skb_shinfo(skb)->frags[i];



	frag->page		  = page;

	frag->page.p		  = page;

	frag->page_offset	  = off;

	skb_frag_size_set(frag, size);

}
@@ -1699,7 +1701,7 @@ static inline void netdev_free_page(struct net_device *dev, struct page *page) 
 */

static inline struct page *skb_frag_page(const skb_frag_t *frag)

{

	return frag->page;

	return frag->page.p;

}



/**
@@ -1785,7 +1787,7 @@ static inline void *skb_frag_address_safe(const skb_frag_t *frag) 
 */

static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page)

{

	frag->page = page;

	frag->page.p = page;

}



/**

net/core/skbuff.c

+3 −3
Original line number Diff line number Diff line
@@ -668,14 +668,14 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) 


	/* skb frags release userspace buffers */

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)

		put_page(skb_shinfo(skb)->frags[i].page);

		skb_frag_unref(skb, i);



	uarg->callback(uarg);



	/* skb frags point to kernel buffers */

	for (i = skb_shinfo(skb)->nr_frags; i > 0; i--) {

		skb_shinfo(skb)->frags[i - 1].page_offset = 0;

		skb_shinfo(skb)->frags[i - 1].page = head;

		__skb_fill_page_desc(skb, i-1, head, 0,

				     skb_shinfo(skb)->frags[i - 1].size);

		head = (struct page *)head->private;

	}