diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 101659cd4b87f2..8cd76037c72481 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -379,21 +379,17 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, struct receive_queue *rq, struct page *page, unsigned int offset, unsigned int len, unsigned int truesize, - bool hdr_valid, unsigned int metasize) + bool hdr_valid, unsigned int metasize, + unsigned int headroom) { struct sk_buff *skb; struct virtio_net_hdr_mrg_rxbuf *hdr; unsigned int copy, hdr_len, hdr_padded_len; - char *p; + int tailroom, shinfo_size; + char *p, *hdr_p; p = page_address(page) + offset; - - /* copy small packet so we can reuse these pages for small data */ - skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN); - if (unlikely(!skb)) - return NULL; - - hdr = skb_vnet_hdr(skb); + hdr_p = p; hdr_len = vi->hdr_len; if (vi->mergeable_rx_bufs) @@ -401,14 +397,38 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, else hdr_padded_len = sizeof(struct padded_vnet_hdr); - /* hdr_valid means no XDP, so we can copy the vnet header */ - if (hdr_valid) - memcpy(hdr, p, hdr_len); + /* If headroom is not 0, there is an offset between the beginning of the + * data and the allocated space, otherwise the data and the allocated + * space are aligned. + */ + if (headroom) { + /* The actual allocated space size is PAGE_SIZE. */ + truesize = PAGE_SIZE; + tailroom = truesize - len - offset; + } else { + tailroom = truesize - len; + } len -= hdr_len; offset += hdr_padded_len; p += hdr_padded_len; + shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + + if (len > GOOD_COPY_LEN && tailroom >= shinfo_size) { + skb = build_skb(p, truesize); + if (unlikely(!skb)) + return NULL; + + skb_put(skb, len); + goto ok; + } + + /* copy small packet so we can reuse these pages for small data */ + skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN); + if (unlikely(!skb)) + return NULL; + /* Copy all frame if it fits skb->head, otherwise * we let virtio_net_hdr_to_skb() and GRO pull headers as needed. */ @@ -418,11 +438,6 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, copy = ETH_HLEN + metasize; skb_put_data(skb, p, copy); - if (metasize) { - __skb_pull(skb, metasize); - skb_metadata_set(skb, metasize); - } - len -= copy; offset += copy; @@ -431,7 +446,7 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, skb_add_rx_frag(skb, 0, page, offset, len, truesize); else put_page(page); - return skb; + goto ok; } /* @@ -458,6 +473,18 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi, if (page) give_pages(rq, page); +ok: + /* hdr_valid means no XDP, so we can copy the vnet header */ + if (hdr_valid) { + hdr = skb_vnet_hdr(skb); + memcpy(hdr, hdr_p, hdr_len); + } + + if (metasize) { + __skb_pull(skb, metasize); + skb_metadata_set(skb, metasize); + } + return skb; } @@ -808,7 +835,7 @@ static struct sk_buff *receive_big(struct net_device *dev, { struct page *page = buf; struct sk_buff *skb = - page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, true, 0); + page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, true, 0, 0); stats->bytes += len - vi->hdr_len; if (unlikely(!skb)) @@ -922,7 +949,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, put_page(page); head_skb = page_to_skb(vi, rq, xdp_page, offset, len, PAGE_SIZE, false, - metasize); + metasize, headroom); return head_skb; } break; @@ -980,7 +1007,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, } head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog, - metasize); + metasize, headroom); curr_skb = head_skb; if (unlikely(!curr_skb))