Imported Upstream version 16.04

[deb_dpdk.git] / drivers / net / virtio / virtqueue.c

diff --git a/drivers/net/virtio/virtqueue.c b/drivers/net/virtio/virtqueue.c
new file mode 100644 (file)
index 0000000..7f60e3e
--- /dev/null
+++ b/drivers/net/virtio/virtqueue.c
@@ -0,0 +1,72 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <stdint.h>
+
+#include <rte_mbuf.h>
+
+#include "virtqueue.h"
+#include "virtio_logs.h"
+#include "virtio_pci.h"
+
+void
+virtqueue_disable_intr(struct virtqueue *vq)
+{
+       /*
+        * Set VRING_AVAIL_F_NO_INTERRUPT to hint host
+        * not to interrupt when it consumes packets
+        * Note: this is only considered a hint to the host
+        */
+       vq->vq_ring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+}
+
+/*
+ * Two types of mbuf to be cleaned:
+ * 1) mbuf that has been consumed by backend but not used by virtio.
+ * 2) mbuf that hasn't been consued by backend.
+ */
+struct rte_mbuf *
+virtqueue_detatch_unused(struct virtqueue *vq)
+{
+       struct rte_mbuf *cookie;
+       int idx;
+
+       if (vq != NULL)
+               for (idx = 0; idx < vq->vq_nentries; idx++) {
+                       cookie = vq->vq_descx[idx].cookie;
+                       if (cookie != NULL) {
+                               vq->vq_descx[idx].cookie = NULL;
+                               return cookie;
+                       }
+               }
+       return NULL;
+}