[PATCH net-next v5 4/9] xen-netback: Change RX path for mapped SKB fragments
From: Zoltan Kiss <hidden>
Date: 2014-01-20 21:27:01
Also in:
lkml, xen-devel
Subsystem:
networking drivers, the rest, xen network backend driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Wei Liu, Paul Durrant
RX path need to know if the SKB fragments are stored on pages from another domain. v4: - indentation fixes Signed-off-by: Zoltan Kiss <redacted> --- drivers/net/xen-netback/netback.c | 46 +++++++++++++++++++++++++++++++++---- 1 file changed, 41 insertions(+), 5 deletions(-)
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index f74fa92..d43444d 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c@@ -226,7 +226,9 @@ static struct xenvif_rx_meta *get_next_rx_buffer(struct xenvif *vif, static void xenvif_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, struct netrx_pending_operations *npo, struct page *page, unsigned long size, - unsigned long offset, int *head) + unsigned long offset, int *head, + struct xenvif *foreign_vif, + grant_ref_t foreign_gref) { struct gnttab_copy *copy_gop; struct xenvif_rx_meta *meta;
@@ -268,8 +270,15 @@ static void xenvif_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, copy_gop->flags = GNTCOPY_dest_gref; copy_gop->len = bytes; - copy_gop->source.domid = DOMID_SELF; - copy_gop->source.u.gmfn = virt_to_mfn(page_address(page)); + if (foreign_vif) { + copy_gop->source.domid = foreign_vif->domid; + copy_gop->source.u.ref = foreign_gref; + copy_gop->flags |= GNTCOPY_source_gref; + } else { + copy_gop->source.domid = DOMID_SELF; + copy_gop->source.u.gmfn = + virt_to_mfn(page_address(page)); + } copy_gop->source.offset = offset; copy_gop->dest.domid = vif->domid;
@@ -330,6 +339,9 @@ static int xenvif_gop_skb(struct sk_buff *skb, int old_meta_prod; int gso_type; int gso_size; + struct ubuf_info *ubuf = skb_shinfo(skb)->destructor_arg; + grant_ref_t foreign_grefs[MAX_SKB_FRAGS]; + struct xenvif *foreign_vif = NULL; old_meta_prod = npo->meta_prod;
@@ -370,6 +382,26 @@ static int xenvif_gop_skb(struct sk_buff *skb, npo->copy_off = 0; npo->copy_gref = req->gref; + if ((skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) && + (ubuf->callback == &xenvif_zerocopy_callback)) { + u16 pending_idx = ubuf->desc; + int i = 0; + struct pending_tx_info *temp = + container_of(ubuf, + struct pending_tx_info, + callback_struct); + foreign_vif = + container_of(temp - pending_idx, + struct xenvif, + pending_tx_info[0]); + do { + pending_idx = ubuf->desc; + foreign_grefs[i++] = + foreign_vif->pending_tx_info[pending_idx].req.gref; + ubuf = (struct ubuf_info *) ubuf->ctx; + } while (ubuf); + } + data = skb->data; while (data < skb_tail_pointer(skb)) { unsigned int offset = offset_in_page(data);
@@ -379,7 +411,9 @@ static int xenvif_gop_skb(struct sk_buff *skb, len = skb_tail_pointer(skb) - data; xenvif_gop_frag_copy(vif, skb, npo, - virt_to_page(data), len, offset, &head); + virt_to_page(data), len, offset, &head, + NULL, + 0); data += len; }
@@ -388,7 +422,9 @@ static int xenvif_gop_skb(struct sk_buff *skb, skb_frag_page(&skb_shinfo(skb)->frags[i]), skb_frag_size(&skb_shinfo(skb)->frags[i]), skb_shinfo(skb)->frags[i].page_offset, - &head); + &head, + foreign_vif, + foreign_grefs[i]); } return npo->meta_prod - old_meta_prod;