netdev - [PATCH net-next 6/7] virtio_net: separate receive

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240508080514.99458-7-xuanzhuo@linux.alibaba.com>
Date: Wed,  8 May 2024 16:05:13 +0800
From: Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
To: netdev@...r.kernel.org
Cc: "David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	"Michael S. Tsirkin" <mst@...hat.com>,
	Jason Wang <jasowang@...hat.com>,
	Xuan Zhuo <xuanzhuo@...ux.alibaba.com>,
	Alexei Starovoitov <ast@...nel.org>,
	Daniel Borkmann <daniel@...earbox.net>,
	Jesper Dangaard Brouer <hawk@...nel.org>,
	John Fastabend <john.fastabend@...il.com>,
	virtualization@...ts.linux.dev,
	bpf@...r.kernel.org
Subject: [PATCH net-next 6/7] virtio_net: separate receive_mergeable

This commit separates the function receive_mergeable(),
put the logic of appending frag to the skb as an independent function.
The subsequent commit will reuse it.

Signed-off-by: Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
---
 drivers/net/virtio/virtnet.h      |  4 ++
 drivers/net/virtio/virtnet_main.c | 77 +++++++++++++++++++------------
 2 files changed, 51 insertions(+), 30 deletions(-)

diff --git a/drivers/net/virtio/virtnet.h b/drivers/net/virtio/virtnet.h
index 9dce5df88fe1..35e8526d2ef3 100644
--- a/drivers/net/virtio/virtnet.h
+++ b/drivers/net/virtio/virtnet.h
@@ -239,4 +239,8 @@ void virtnet_rx_pause(struct virtnet_info *vi, struct virtnet_rq *rq);
 void virtnet_rx_resume(struct virtnet_info *vi, struct virtnet_rq *rq);
 void virtnet_tx_pause(struct virtnet_info *vi, struct virtnet_sq *sq);
 void virtnet_tx_resume(struct virtnet_info *vi, struct virtnet_sq *sq);
+struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb,
+					struct sk_buff *curr_skb,
+					struct page *page, void *buf,
+					int len, int truesize);
 #endif
diff --git a/drivers/net/virtio/virtnet_main.c b/drivers/net/virtio/virtnet_main.c
index 1701640980ba..fcfe190300a6 100644
--- a/drivers/net/virtio/virtnet_main.c
+++ b/drivers/net/virtio/virtnet_main.c
@@ -1549,6 +1549,49 @@ static struct sk_buff *receive_mergeable_xdp(struct net_device *dev,
 	return NULL;
 }
 
+struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb,
+					struct sk_buff *curr_skb,
+					struct page *page, void *buf,
+					int len, int truesize)
+{
+	int num_skb_frags;
+	int offset;
+
+	num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
+	if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
+		struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
+
+		if (unlikely(!nskb))
+			return NULL;
+
+		if (curr_skb == head_skb)
+			skb_shinfo(curr_skb)->frag_list = nskb;
+		else
+			curr_skb->next = nskb;
+		curr_skb = nskb;
+		head_skb->truesize += nskb->truesize;
+		num_skb_frags = 0;
+	}
+
+	if (curr_skb != head_skb) {
+		head_skb->data_len += len;
+		head_skb->len += len;
+		head_skb->truesize += truesize;
+	}
+
+	offset = buf - page_address(page);
+	if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
+		put_page(page);
+		skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
+				     len, truesize);
+	} else {
+		skb_add_rx_frag(curr_skb, num_skb_frags, page,
+				offset, len, truesize);
+	}
+
+	return curr_skb;
+}
+
 static struct sk_buff *receive_mergeable(struct net_device *dev,
 					 struct virtnet_info *vi,
 					 struct virtnet_rq *rq,
@@ -1598,8 +1641,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 	if (unlikely(!curr_skb))
 		goto err_skb;
 	while (--num_buf) {
-		int num_skb_frags;
-
 		buf = virtnet_rq_get_buf(rq, &len, &ctx);
 		if (unlikely(!buf)) {
 			pr_debug("%s: rx error: %d buffers out of %d missing\n",
@@ -1624,34 +1665,10 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 			goto err_skb;
 		}
 
-		num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
-		if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
-			struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
-
-			if (unlikely(!nskb))
-				goto err_skb;
-			if (curr_skb == head_skb)
-				skb_shinfo(curr_skb)->frag_list = nskb;
-			else
-				curr_skb->next = nskb;
-			curr_skb = nskb;
-			head_skb->truesize += nskb->truesize;
-			num_skb_frags = 0;
-		}
-		if (curr_skb != head_skb) {
-			head_skb->data_len += len;
-			head_skb->len += len;
-			head_skb->truesize += truesize;
-		}
-		offset = buf - page_address(page);
-		if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
-			put_page(page);
-			skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
-					     len, truesize);
-		} else {
-			skb_add_rx_frag(curr_skb, num_skb_frags, page,
-					offset, len, truesize);
-		}
+		curr_skb  = virtnet_skb_append_frag(head_skb, curr_skb, page,
+						    buf, len, truesize);
+		if (!curr_skb)
+			goto err_skb;
 	}
 
 	ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
-- 
2.32.0.3.g01195cf9f