openvswitch.h: Clarify use of key attributes.

[sliver-openvswitch.git] / include / linux / openvswitch.h

diff --git a/include/linux/openvswitch.h b/include/linux/openvswitch.h
index 1aa9158..d7f85ff 100644 (file)
--- a/include/linux/openvswitch.h
+++ b/include/linux/openvswitch.h
@@ -109,6 +109,7 @@ enum ovs_datapath_attr {
 
 #define OVS_DP_ATTR_MAX (__OVS_DP_ATTR_MAX - 1)
 
+/* All 64-bit integers within Netlink messages are 4-byte aligned only. */
 struct ovs_dp_stats {
        __u64 n_hit;             /* Number of flow table matches. */
        __u64 n_missed;          /* Number of flow table misses. */
@@ -170,7 +171,9 @@ enum ovs_packet_cmd {
  * @OVS_PACKET_ATTR_KEY: Present for all notifications.  Contains the flow key
  * extracted from the packet as nested %OVS_KEY_ATTR_* attributes.  This allows
  * userspace to adapt its flow setup strategy by comparing its notion of the
- * flow key against the kernel's.
+ * flow key against the kernel's.  When used with %OVS_PACKET_CMD_EXECUTE, only
+ * metadata key fields (e.g. priority, skb mark) are honored.  All the packet
+ * header fields are parsed from the packet instead.
  * @OVS_PACKET_ATTR_ACTIONS: Contains actions for the packet.  Used
  * for %OVS_PACKET_CMD_EXECUTE.  It has nested %OVS_ACTION_ATTR_* attributes.
  * @OVS_PACKET_ATTR_USERDATA: Present for an %OVS_PACKET_CMD_ACTION
@@ -312,7 +315,8 @@ enum ovs_key_attr {
        OVS_KEY_ATTR_TUNNEL,    /* Nested set of ovs_tunnel attributes */
        OVS_KEY_ATTR_SCTP,      /* struct ovs_key_sctp */
        OVS_KEY_ATTR_TCP_FLAGS, /* be16 TCP flags. */
-       OVS_KEY_ATTR_DP_HASH,   /* u32 hash value */
+       OVS_KEY_ATTR_DP_HASH,   /* u32 hash value. Value 0 indicates the hash
+                                  is not computed by the datapath. */
        OVS_KEY_ATTR_RECIRC_ID, /* u32 recirc id */
 #ifdef __KERNEL__
        /* Only used within kernel data path. */