static void netbk_add_frag_responses(struct xenvif *vif, int status,
struct netbk_rx_meta *meta,
int nr_meta_slots)
{
int i;
unsigned long offset;
/* No fragments used */
if (nr_meta_slots <= 1)
return;
nr_meta_slots--;
for (i = 0; i < nr_meta_slots; i++) {
int flags;
if (i == nr_meta_slots - 1)
flags = 0;
else
flags = XEN_NETRXF_more_data;
offset = 0;
make_rx_response(vif, meta[i].id, status, offset,
meta[i].size, flags);
}
}
static void netbk_add_frag_responses(netif_t *netif, int status,
struct netbk_rx_meta *meta, int nr_frags)
{
int i;
unsigned long offset;
for (i = 0; i < nr_frags; i++) {
int id = meta[i].id;
int flags = (i == nr_frags - 1) ? 0 : NETRXF_more_data;
if (meta[i].copy)
offset = 0;
else
offset = meta[i].frag.page_offset;
make_rx_response(netif, id, status, offset,
meta[i].frag.size, flags);
}
}
static void xenvif_rx_action(struct xenvif *vif)
{
s8 status;
u16 flags;
struct xen_netif_rx_response *resp;
struct sk_buff_head rxq;
struct sk_buff *skb;
LIST_HEAD(notify);
int ret;
unsigned long offset;
bool need_to_notify = false;
struct netrx_pending_operations npo = {
.copy = vif->grant_copy_op,
.meta = vif->meta,
};
skb_queue_head_init(&rxq);
while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) {
RING_IDX max_slots_needed;
RING_IDX old_req_cons;
RING_IDX ring_slots_used;
int i;
/* We need a cheap worse case estimate for the number of
* slots we'll use.
*/
max_slots_needed = DIV_ROUND_UP(offset_in_page(skb->data) +
skb_headlen(skb),
PAGE_SIZE);
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
unsigned int size;
unsigned int offset;
size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
offset = skb_shinfo(skb)->frags[i].page_offset;
/* For a worse-case estimate we need to factor in
* the fragment page offset as this will affect the
* number of times xenvif_gop_frag_copy() will
* call start_new_rx_buffer().
*/
max_slots_needed += DIV_ROUND_UP(offset + size,
PAGE_SIZE);
}
/* To avoid the estimate becoming too pessimal for some
* frontends that limit posted rx requests, cap the estimate
* at MAX_SKB_FRAGS.
*/
if (max_slots_needed > MAX_SKB_FRAGS)
max_slots_needed = MAX_SKB_FRAGS;
/* We may need one more slot for GSO metadata */
if (skb_is_gso(skb) &&
(skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6))
max_slots_needed++;
/* If the skb may not fit then bail out now */
if (!xenvif_rx_ring_slots_available(vif, max_slots_needed)) {
skb_queue_head(&vif->rx_queue, skb);
need_to_notify = true;
vif->rx_last_skb_slots = max_slots_needed;
break;
} else
vif->rx_last_skb_slots = 0;
old_req_cons = vif->rx.req_cons;
XENVIF_RX_CB(skb)->meta_slots_used = xenvif_gop_skb(skb, &npo);
ring_slots_used = vif->rx.req_cons - old_req_cons;
BUG_ON(ring_slots_used > max_slots_needed);
__skb_queue_tail(&rxq, skb);
}
BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta));
if (!npo.copy_prod)
goto done;
BUG_ON(npo.copy_prod > MAX_GRANT_COPY_OPS);
gnttab_batch_copy(vif->grant_copy_op, npo.copy_prod);
while ((skb = __skb_dequeue(&rxq)) != NULL) {
if ((1 << vif->meta[npo.meta_cons].gso_type) &
vif->gso_prefix_mask) {
resp = RING_GET_RESPONSE(&vif->rx,
vif->rx.rsp_prod_pvt++);
resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data;
resp->offset = vif->meta[npo.meta_cons].gso_size;
resp->id = vif->meta[npo.meta_cons].id;
resp->status = XENVIF_RX_CB(skb)->meta_slots_used;
npo.meta_cons++;
XENVIF_RX_CB(skb)->meta_slots_used--;
}
vif->dev->stats.tx_bytes += skb->len;
vif->dev->stats.tx_packets++;
status = xenvif_check_gop(vif,
XENVIF_RX_CB(skb)->meta_slots_used,
&npo);
if (XENVIF_RX_CB(skb)->meta_slots_used == 1)
flags = 0;
else
flags = XEN_NETRXF_more_data;
if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */
flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated;
else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
/* remote but checksummed. */
flags |= XEN_NETRXF_data_validated;
offset = 0;
resp = make_rx_response(vif, vif->meta[npo.meta_cons].id,
status, offset,
vif->meta[npo.meta_cons].size,
flags);
if ((1 << vif->meta[npo.meta_cons].gso_type) &
vif->gso_mask) {
struct xen_netif_extra_info *gso =
(struct xen_netif_extra_info *)
RING_GET_RESPONSE(&vif->rx,
vif->rx.rsp_prod_pvt++);
resp->flags |= XEN_NETRXF_extra_info;
gso->u.gso.type = vif->meta[npo.meta_cons].gso_type;
gso->u.gso.size = vif->meta[npo.meta_cons].gso_size;
gso->u.gso.pad = 0;
gso->u.gso.features = 0;
gso->type = XEN_NETIF_EXTRA_TYPE_GSO;
gso->flags = 0;
}
xenvif_add_frag_responses(vif, status,
vif->meta + npo.meta_cons + 1,
XENVIF_RX_CB(skb)->meta_slots_used);
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret);
need_to_notify |= !!ret;
npo.meta_cons += XENVIF_RX_CB(skb)->meta_slots_used;
dev_kfree_skb(skb);
}
done:
if (need_to_notify)
notify_remote_via_irq(vif->rx_irq);
}
void xenvif_check_rx_xenvif(struct xenvif *vif)
{
int more_to_do;
RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
if (more_to_do)
napi_schedule(&vif->napi);
}