[bpf-next V5 PATCH 07/15] virtio_net: convert to use generic xdp_frame and xdp_return_frame API
flat view
STALE3135d
SUPERSEDED
From: Jesper Dangaard Brouer <hidden>
Date: 2018-03-23 12:18:38
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, Eugenio Pérez
Revision v5 of 11 in this series.
Revisions (11)
The virtio_net driver assumes XDP frames are always released based on page refcnt (via put_page). Thus, is only queues the XDP data pointer address and uses virt_to_head_page() to retrieve struct page. Use the XDP return API to get away from such assumptions. Instead queue an xdp_frame, which allow us to use the xdp_return_frame API, when releasing the frame. Signed-off-by: Jesper Dangaard Brouer <redacted> --- drivers/net/virtio_net.c | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 23374603e4d9..6c4220450506 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -419,30 +419,41 @@ static bool __virtnet_xdp_xmit(struct virtnet_info *vi, struct xdp_buff *xdp) { struct virtio_net_hdr_mrg_rxbuf *hdr; - unsigned int len; + struct xdp_frame *xdpf, *xdpf_sent; struct send_queue *sq; + unsigned int len; unsigned int qp; - void *xdp_sent; int err; qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id(); sq = &vi->sq[qp]; /* Free up any pending old buffers before queueing new ones. */ - while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) { - struct page *sent_page = virt_to_head_page(xdp_sent); + while ((xdpf_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) + xdp_return_frame(xdpf_sent->data, &xdpf_sent->mem); - put_page(sent_page); - } + xdpf = convert_to_xdp_frame(xdp); + if (unlikely(!xdpf)) + return -EOVERFLOW; + + /* virtqueue want to use data area in-front of packet */ + if (unlikely(xdpf->metasize > 0)) + return -EOPNOTSUPP; + + if (unlikely(xdpf->headroom < vi->hdr_len)) + return -EOVERFLOW; - xdp->data -= vi->hdr_len; + /* Make room for virtqueue hdr (also change xdpf->headroom?) */ + xdpf->data -= vi->hdr_len; /* Zero header and leave csum up to XDP layers */ - hdr = xdp->data; + hdr = xdpf->data; memset(hdr, 0, vi->hdr_len); + hdr->hdr.hdr_len = xdpf->len; /* Q: is this needed? */ + xdpf->len += vi->hdr_len; - sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data); + sg_init_one(sq->sg, xdpf->data, xdpf->len); - err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC); + err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdpf, GFP_ATOMIC); if (unlikely(err)) return false; /* Caller handle free/refcnt */