Upon receiving an event channel notification from the frontend, schedule
the bottom half. From the bottom half, read one request from the ring,
create a pdu and call pdu_submit to handle it.
For now, only handle one request per ring at a time.
Signed-off-by: Stefano Stabellini <stef...@aporeto.com>
CC: anthony.per...@citrix.com
CC: jgr...@suse.com
CC: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
CC: Greg Kurz <gr...@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index bfc6eca..60d49d1 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -103,12 +103,62 @@ static int xen_9pfs_init(struct XenDevice *xendev)
return 0;
}
+static int xen_9pfs_receive(Xen9pfsRing *ring)
+{
+ P9MsgHeader h;
+ RING_IDX cons, prod, masked_prod, masked_cons;
+ V9fsPDU *pdu;
+
+ if (ring->inprogress) {
+ return 0;
+ }
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+
+ if (xen_9pfs_queued(prod, cons, XEN_FLEX_RING_SIZE(ring->ring_order)) <
+ sizeof(h)) {
+ return 0;
+ }
+ ring->inprogress = true;
+
+ masked_prod = xen_9pfs_mask(prod, XEN_FLEX_RING_SIZE(ring->ring_order));
+ masked_cons = xen_9pfs_mask(cons, XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ xen_9pfs_read_packet((uint8_t *) &h, ring->ring.out, sizeof(h),
+ masked_prod, &masked_cons,
+ XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ /* cannot fail, because we only handle one request per ring at a time */
+ pdu = pdu_alloc(&ring->priv->state);
+ pdu->size = le32_to_cpu(h.size_le);
+ pdu->id = h.id;
+ pdu->tag = le32_to_cpu(h.tag_le);
+ ring->out_size = le32_to_cpu(h.size_le);
+ ring->out_cons = cons + le32_to_cpu(h.size_le);
+
+ qemu_co_queue_init(&pdu->complete);
+ pdu_submit(pdu);
+
+ return 0;
+}
+
static void xen_9pfs_bh(void *opaque)
{
+ Xen9pfsRing *ring = opaque;
+ xen_9pfs_receive(ring);
}
static void xen_9pfs_evtchn_event(void *opaque)
{
+ Xen9pfsRing *ring = opaque;
+ evtchn_port_t port;
+
+ port = xenevtchn_pending(ring->evtchndev);
+ xenevtchn_unmask(ring->evtchndev, port);
+
+ qemu_bh_schedule(ring->bh);
}
static int xen_9pfs_free(struct XenDevice *xendev)
--
1.9.1
