[PATCH net-next 2/2] virtio-net: fix the XDP truesize calculation for mergeable buffers
From: Jason Wang <jasowang@redhat.com>
Date: 2020-05-06 06:16:55
Also in:
bpf, lkml, virtualization
Subsystem:
networking drivers, the rest, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
We should not exclude headroom and tailroom when XDP is set. So this patch fixes this by initializing the truesize from PAGE_SIZE when XDP is set. Cc: Jesper Dangaard Brouer <redacted> Signed-off-by: Jason Wang <jasowang@redhat.com> --- drivers/net/virtio_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 98dd75b665a5..3f3aa8308918 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -1184,7 +1184,7 @@ static int add_recvbuf_mergeable(struct virtnet_info *vi, char *buf; void *ctx; int err; - unsigned int len, hole; + unsigned int len, hole, truesize; /* Extra tailroom is needed to satisfy XDP's assumption. This * means rx frags coalescing won't work, but consider we've
@@ -1194,6 +1194,7 @@ static int add_recvbuf_mergeable(struct virtnet_info *vi, if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp))) return -ENOMEM; + truesize = headroom ? PAGE_SIZE : len; buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset; buf += headroom; /* advance address leaving hole at front of pkt */ get_page(alloc_frag->page);
@@ -1205,11 +1206,12 @@ static int add_recvbuf_mergeable(struct virtnet_info *vi, * the current buffer. */ len += hole; + truesize += hole; alloc_frag->offset += hole; } sg_init_one(rq->sg, buf, len); - ctx = mergeable_len_to_ctx(len, headroom); + ctx = mergeable_len_to_ctx(truesize, headroom); err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp); if (err < 0) put_page(virt_to_head_page(buf));
--
2.20.1