[ovs-dev] [PATCHv11 1/5] datapath: Add UFID interface to openvswitch.h.

[Pravin Shelar]

On Tue, Nov 25, 2014 at 5:07 PM, Joe Stringer <joestringer at nicira.com> wrote:
> An upcoming set of patches will implement support for indexing flows by
> Unique Flow IDentifiers (UFID) rather than the traditional unmasked key.
> This patch implements the interface changes required. The implementation
> will follow.
>
> Signed-off-by: Joe Stringer <joestringer at nicira.com>
> CC: Pravin B Shelar <pshelar at nicira.com>

Acked-by: Pravin B Shelar <pshelar at nicira.com>
> ---
> v11: Split from "datapath: Add support for unique flow identifiers."
> ---
>  datapath/README.md                                |   13 +++++++++++++
>  datapath/linux/compat/include/linux/openvswitch.h |   19 +++++++++++++++++++
>  2 files changed, 32 insertions(+)
>
> diff --git a/datapath/README.md b/datapath/README.md
> index a8effa3..9c03a2b 100644
> --- a/datapath/README.md
> +++ b/datapath/README.md
> @@ -131,6 +131,19 @@ performs best-effort detection of overlapping wildcarded flows and may reject
>  some but not all of them. However, this behavior may change in future versions.
>
>
> +Unique flow identifiers
> +-----------------------
> +
> +An alternative to using the original match portion of a key as the handle for
> +flow identification is a unique flow identifier, or "UFID". UFIDs are optional
> +for both the kernel and user space program.
> +
> +User space programs that support UFID are expected to provide it during flow
> +setup in addition to the flow, then refer to the flow using the UFID for all
> +future operations. The kernel is not required to index flows by the original
> +flow key if a UFID is specified.
> +
> +
>  Basic rule for evolving flow keys
>  ---------------------------------
>
> diff --git a/datapath/linux/compat/include/linux/openvswitch.h b/datapath/linux/compat/include/linux/openvswitch.h
> index c8fa66e..67715f8 100644
> --- a/datapath/linux/compat/include/linux/openvswitch.h
> +++ b/datapath/linux/compat/include/linux/openvswitch.h
> @@ -471,6 +471,13 @@ struct ovs_key_nd {
>   * a wildcarded match. Omitting attribute is treated as wildcarding all
>   * corresponding fields. Optional for all requests. If not present,
>   * all flow key bits are exact match bits.
> + * @OVS_FLOW_ATTR_UFID: A unique identifier for the flow. Causes the flow to
> + * be indexed by this value rather than the %OVS_FLOW_ATTR_KEY%. Optional
> + * for all requests. Present in notifications if the flow was created with a
> + * UFID.
> + * @OVS_FLOW_ATTR_UFID_FLAGS: A 32-bit value of OR'd OVS_UFID_F_* flags that
> + * provide alternative semantics for flow installation and retrieval. Optional
> + * for all requests.
>   *
>   * These attributes follow the &struct ovs_header within the Generic Netlink
>   * payload for %OVS_FLOW_* commands.
> @@ -486,12 +493,24 @@ enum ovs_flow_attr {
>         OVS_FLOW_ATTR_MASK,      /* Sequence of OVS_KEY_ATTR_* attributes. */
>         OVS_FLOW_ATTR_PROBE,     /* Flow operation is a feature probe, error
>                                   * logging should be suppressed. */
> +       OVS_FLOW_ATTR_UFID,      /* Variable length unique flow identifier. */
> +       OVS_FLOW_ATTR_UFID_FLAGS,/* u32 of OVS_UFID_F_*. */
>         __OVS_FLOW_ATTR_MAX
>  };
>
>  #define OVS_FLOW_ATTR_MAX (__OVS_FLOW_ATTR_MAX - 1)
>
>  /**
> + * Omit attributes for notifications.
> + *
> + * If a datapath request contains an OVS_UFID_F_OMIT_* flag, then the datapath
> + * may omit the corresponding 'ovs_flow_attr' from the response.
> + */
> +#define OVS_UFID_F_OMIT_KEY      (1 << 0)
> +#define OVS_UFID_F_OMIT_MASK     (1 << 1)
> +#define OVS_UFID_F_OMIT_ACTIONS  (1 << 2)
> +
> +/**
>   * enum ovs_sample_attr - Attributes for %OVS_ACTION_ATTR_SAMPLE action.
>   * @OVS_SAMPLE_ATTR_PROBABILITY: 32-bit fraction of packets to sample with
>   * @OVS_ACTION_ATTR_SAMPLE.  A value of 0 samples no packets, a value of
> --
> 1.7.10.4
>