[dpdk-dev] [PATCH v5 02/15] vhost: add helpers for packed virtqueues

[Maxime Coquelin]

From: Jens Freimann <jfreimann at redhat.com>

Add some helper functions to check descriptor flags
and check if a vring is of type packed.

Signed-off-by: Jens Freimann <jfreimann at redhat.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 lib/librte_vhost/vhost.h         |  6 ++++++
 lib/librte_vhost/virtio-packed.h | 16 ++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index bf2059198..34a614c97 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -319,6 +319,12 @@ struct virtio_net {
 	struct vhost_user_extern_ops extern_ops;
 } __rte_cache_aligned;
 
+static __rte_always_inline bool
+vq_is_packed(struct virtio_net *dev)
+{
+	return dev->features & (1ull << VIRTIO_F_RING_PACKED);
+}
+
 #define VHOST_LOG_PAGE	4096
 
 /*
diff --git a/lib/librte_vhost/virtio-packed.h b/lib/librte_vhost/virtio-packed.h
index 744b3991b..21fe5045b 100644
--- a/lib/librte_vhost/virtio-packed.h
+++ b/lib/librte_vhost/virtio-packed.h
@@ -19,4 +19,20 @@ struct vring_desc_packed {
 	uint16_t flags;
 };
 
+
+static inline int
+desc_is_avail(struct vring_desc_packed *desc, uint16_t wrap_counter)
+{
+	if (wrap_counter == 1) {
+		if ((desc->flags & VRING_DESC_F_AVAIL) &&
+				!(desc->flags & VRING_DESC_F_USED))
+			return 1;
+	} else {
+		if (!(desc->flags & VRING_DESC_F_AVAIL) &&
+				(desc->flags & VRING_DESC_F_USED))
+			return 1;
+	}
+	return 0;
+}
+
 #endif /* __VIRTIO_PACKED_H */
-- 
2.14.4