Commit 27accb3c authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Jakub Kicinski
Browse files

veth: rely on skb_pp_cow_data utility routine 



Rely on skb_pp_cow_data utility routine and remove duplicated code.

Acked-by: default avatarJesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: default avatarToke Hoiland-Jorgensen <toke@redhat.com>
Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/029cc14cce41cb242ee7efdcf32acc81f1ce4e9f.1707729884.git.lorenzo@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e6d5dbdd

drivers/net/veth.c

+2 −72
Original line number Diff line number Diff line
@@ -729,80 +729,10 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq, 
	if (skb_shared(skb) || skb_head_is_locked(skb) ||

	    skb_shinfo(skb)->nr_frags ||

	    skb_headroom(skb) < XDP_PACKET_HEADROOM) {

		u32 size, len, max_head_size, off, truesize, page_offset;

		struct sk_buff *nskb;

		struct page *page;

		int i, head_off;

		void *va;



		/* We need a private copy of the skb and data buffers since

		 * the ebpf program can modify it. We segment the original skb

		 * into order-0 pages without linearize it.

		 *

		 * Make sure we have enough space for linear and paged area

		 */

		max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE -

						  VETH_XDP_HEADROOM);

		if (skb->len > PAGE_SIZE * MAX_SKB_FRAGS + max_head_size)

			goto drop;



		size = min_t(u32, skb->len, max_head_size);

		truesize = SKB_HEAD_ALIGN(size) + VETH_XDP_HEADROOM;



		/* Allocate skb head */

		va = page_pool_dev_alloc_va(rq->page_pool, &truesize);

		if (!va)

			goto drop;



		nskb = napi_build_skb(va, truesize);

		if (!nskb) {

			page_pool_free_va(rq->page_pool, va, true);

			goto drop;

		}



		skb_reserve(nskb, VETH_XDP_HEADROOM);

		skb_copy_header(nskb, skb);

		skb_mark_for_recycle(nskb);



		if (skb_copy_bits(skb, 0, nskb->data, size)) {

			consume_skb(nskb);

			goto drop;

		}

		skb_put(nskb, size);



		head_off = skb_headroom(nskb) - skb_headroom(skb);

		skb_headers_offset_update(nskb, head_off);



		/* Allocate paged area of new skb */

		off = size;

		len = skb->len - off;



		for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {

			size = min_t(u32, len, PAGE_SIZE);

			truesize = size;



			page = page_pool_dev_alloc(rq->page_pool, &page_offset,

						   &truesize);

			if (!page) {

				consume_skb(nskb);

				goto drop;

			}



			skb_add_rx_frag(nskb, i, page, page_offset, size,

					truesize);

			if (skb_copy_bits(skb, off,

					  page_address(page) + page_offset,

					  size)) {

				consume_skb(nskb);

		if (skb_pp_cow_data(rq->page_pool, pskb, XDP_PACKET_HEADROOM))

			goto drop;

			}



			len -= size;

			off += size;

		}



		consume_skb(skb);

		skb = nskb;

		skb = *pskb;

	}



	/* SKB "head" area always have tailroom for skb_shared_info */

include/linux/skbuff.h

+2 −0
Original line number Diff line number Diff line
@@ -3446,6 +3446,8 @@ static inline void skb_frag_ref(struct sk_buff *skb, int f) 
	__skb_frag_ref(&skb_shinfo(skb)->frags[f]);

}



int skb_pp_cow_data(struct page_pool *pool, struct sk_buff **pskb,

		    unsigned int headroom);

int skb_cow_data_for_xdp(struct page_pool *pool, struct sk_buff **pskb,

			 struct bpf_prog *prog);

bool napi_pp_put_page(struct page *page, bool napi_safe);

net/core/skbuff.c

+3 −2
Original line number Diff line number Diff line
@@ -895,7 +895,7 @@ static bool is_pp_page(struct page *page) 
	return (page->pp_magic & ~0x3UL) == PP_SIGNATURE;

}



static int skb_pp_cow_data(struct page_pool *pool, struct sk_buff **pskb,

int skb_pp_cow_data(struct page_pool *pool, struct sk_buff **pskb,

		    unsigned int headroom)

{

#if IS_ENABLED(CONFIG_PAGE_POOL)
@@ -975,6 +975,7 @@ static int skb_pp_cow_data(struct page_pool *pool, struct sk_buff **pskb, 
	return -EOPNOTSUPP;

#endif

}

EXPORT_SYMBOL(skb_pp_cow_data);



int skb_cow_data_for_xdp(struct page_pool *pool, struct sk_buff **pskb,

			 struct bpf_prog *prog)