virtio-net: Introduce hash report feature

The feature VIRTIO_NET_F_HASH_REPORT extends the
layout of the packet and requests the device to
calculate hash on incoming packets and report it
in the packet header.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Link: https://lore.kernel.org/r/20200302115003.14877-4-yuri.benditovich@daynix.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
index aec6fac..19d23e5 100644 (file)
--- a/include/uapi/linux/virtio_net.h
+++ b/include/uapi/linux/virtio_net.h
@@ -57,6 +57,7 @@
                                         * Steering */
 #define VIRTIO_NET_F_CTRL_MAC_ADDR 23  /* Set MAC address */
 
+#define VIRTIO_NET_F_HASH_REPORT  57   /* Supports hash report */
 #define VIRTIO_NET_F_RSS         60    /* Supports RSS RX steering */
 #define VIRTIO_NET_F_RSC_EXT     61    /* extended coalescing info */
 #define VIRTIO_NET_F_STANDBY     62    /* Act as standby for another device
@@ -156,6 +157,23 @@ struct virtio_net_hdr_v1 {
        __virtio16 num_buffers; /* Number of merged rx buffers */
 };
 
+struct virtio_net_hdr_v1_hash {
+       struct virtio_net_hdr_v1 hdr;
+       __le32 hash_value;
+#define VIRTIO_NET_HASH_REPORT_NONE            0
+#define VIRTIO_NET_HASH_REPORT_IPv4            1
+#define VIRTIO_NET_HASH_REPORT_TCPv4           2
+#define VIRTIO_NET_HASH_REPORT_UDPv4           3
+#define VIRTIO_NET_HASH_REPORT_IPv6            4
+#define VIRTIO_NET_HASH_REPORT_TCPv6           5
+#define VIRTIO_NET_HASH_REPORT_UDPv6           6
+#define VIRTIO_NET_HASH_REPORT_IPv6_EX         7
+#define VIRTIO_NET_HASH_REPORT_TCPv6_EX        8
+#define VIRTIO_NET_HASH_REPORT_UDPv6_EX        9
+       __le16 hash_report;
+       __le16 padding;
+};
+
 #ifndef VIRTIO_NET_NO_LEGACY
 /* This header comes first in the scatter-gather list.
  * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
@@ -305,6 +323,24 @@ struct virtio_net_rss_config {
  #define VIRTIO_NET_CTRL_MQ_RSS_CONFIG          1
 
 /*
+ * The command VIRTIO_NET_CTRL_MQ_HASH_CONFIG requests the device
+ * to include in the virtio header of the packet the value of the
+ * calculated hash and the report type of hash. It also provides
+ * parameters for hash calculation. The command requires feature
+ * VIRTIO_NET_F_HASH_REPORT to be negotiated to extend the
+ * layout of virtio header as defined in virtio_net_hdr_v1_hash.
+ */
+struct virtio_net_hash_config {
+       __le32 hash_types;
+       /* for compatibility with virtio_net_rss_config */
+       __le16 reserved[4];
+       __u8 hash_key_length;
+       __u8 hash_key_data[/* hash_key_length */];
+};
+
+ #define VIRTIO_NET_CTRL_MQ_HASH_CONFIG         2
+
+/*
  * Control network offloads
  *
  * Reconfigures the network offloads that Guest can handle.