net: veth: use newly added page pool API for veth with xdp

Use page_pool_alloc() API to allocate memory with least
memory utilization and performance penalty.

Signed-off-by: Yunsheng Lin <[email protected]>
CC: Lorenzo Bianconi <[email protected]>
CC: Alexander Duyck <[email protected]>
CC: Liang Chen <[email protected]>
CC: Alexander Lobakin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Yunsheng Lin

drivers/net/veth.c

@@ -737,10 +737,11 @@ 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;
+		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
@@ -753,22 +754,24 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
 		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 */
-		page = page_pool_dev_alloc_pages(rq->page_pool);
-		if (!page)
+		va = page_pool_dev_alloc_va(rq->page_pool, &truesize);
+		if (!va)
 			goto drop;
 
-		nskb = napi_build_skb(page_address(page), PAGE_SIZE);
+		nskb = napi_build_skb(va, truesize);
 		if (!nskb) {
-			page_pool_put_full_page(rq->page_pool, page, true);
+			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);
 
-		size = min_t(u32, skb->len, max_head_size);
 		if (skb_copy_bits(skb, 0, nskb->data, size)) {
 			consume_skb(nskb);
 			goto drop;
@@ -783,14 +786,18 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
 		len = skb->len - off;
 
 		for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {
-			page = page_pool_dev_alloc_pages(rq->page_pool);
+			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;
 			}
 
-			size = min_t(u32, len, PAGE_SIZE);
-			skb_add_rx_frag(nskb, i, page, 0, size, PAGE_SIZE);
+			skb_add_rx_frag(nskb, i, page, page_offset, size,
+					truesize);
 			if (skb_copy_bits(skb, off, page_address(page),
 					  size)) {
 				consume_skb(nskb);