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From: Ori Kam <orika@mellanox.com>
To: "Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>
Cc: "ferruh.yigit@intel.com" <ferruh.yigit@intel.com>,
	"declan.doherty@intel.com" <declan.doherty@intel.com>,
	"dev@dpdk.org" <dev@dpdk.org>,
	Adrien Mazarguil <adrien.mazarguil@6wind.com>
Subject: Re: [dpdk-dev] [RFC] ethdev: support tunnel encapsulation action
Date: Mon, 11 Jun 2018 07:27:22 +0000	[thread overview]
Message-ID: <AM4PR05MB342592F41928FB6116D490A9DB780@AM4PR05MB3425.eurprd05.prod.outlook.com> (raw)
In-Reply-To: <20180611065317.tco5xy6eettg4obo@laranjeiro-vm.dev.6wind.com>

Hi

No you shouldn't understand this.
I still think that the [1] proposal is the correct 
approach, but due to a very short time frame for this
release I suggest this as intermediate solution.

I want to get comments and open discussion regarding
the proposal and in worst case add it to next release.

Ori

> -----Original Message-----
> From: Nélio Laranjeiro [mailto:nelio.laranjeiro@6wind.com]
> Sent: Monday, June 11, 2018 9:53 AM
> To: Ori Kam <orika@mellanox.com>
> Cc: ferruh.yigit@intel.com; declan.doherty@intel.com; dev@dpdk.org;
> Adrien Mazarguil <adrien.mazarguil@6wind.com>
> Subject: Re: [RFC] ethdev: support tunnel encapsulation action
> 
> Hi Ori,
> 
> Should we understand this proposal is nacked by [1] you have also
> proposed?
> 
> If yes, answer to this one with a self-nack to make it clear.
> 
> Thanks,
> 
> On Tue, Jun 05, 2018 at 06:48:28PM +0300, Ori Kam wrote:
> > This RFC contain proposal to add generic support for tunnel
> > encapsulation/decapsulation.
> >
> > Due to the fact that there are many possible tunnel types
> > and each tunnel type has number of header variations, there
> > is a need for some generic command.
> >
> > example for tunnel headers in case of MPLSoGRE:
> > ETH / VLAN / IPV4 / GRE / MPLS / ETH / IP / L4-L7
> > ETH / VLAN / IPV6 / GRE / MPLS / ETH / IP / L4-L7
> > ETH / IPV4 / GRE / MPLS / ETH / IP / L4-L7
> > ETH / IPV6 / GRE / MPLS / ETH / IP / L4-L7
> > ETH / VLAN / IPV4 / GRE / MPLS / IP / L4-L7
> > ETH / VLAN / IPV6 / GRE / MPLS / IP / L4-L7
> > ETH / IPV4 / GRE / MPLS / IP / L4-L7
> > ETH / IPV6 / GRE / MPLS / IP / L4-L7
> >
> > As can be seen from the examples some of the encapsulation
> > is done by overwriting the inner L2 packet spec.
> >
> > To support all of those configuration it is much
> > easer if we create 2 encap functions one that
> > is used to encap L2 packet and one that is used
> > to encap L3 packet by removing the L2 and applying
> > the encapsulation header.
> >
> > The use of void * buffer will enable the
> > insertion of any valid encapsulation header.
> > the use of such a buffer will also simplify the processing
> > needed to validate and apply vs the use of rte_flow_items.
> > The use of a buffer will also will be easer
> > for some applications (for example vrouter)
> >
> > For decap we will also have 2 actions
> > one for decaping a packet with inner L2
> > and one for decaping a packet with inner L3.
> > when decaping L3 packet the user should
> > supplay the L2 data which should be added to the inner packet.
> >
> > Signed-off-by: Ori Kam <orika@mellanox.com>
> > ---
> >  doc/guides/prog_guide/rte_flow.rst |  141 ++++++++++++++----------------
> -
> >  lib/librte_ethdev/rte_flow.h       |  165 +++++++++++++++++++++-----------
> ---
> >  2 files changed, 161 insertions(+), 145 deletions(-)
> >
> > diff --git a/doc/guides/prog_guide/rte_flow.rst
> b/doc/guides/prog_guide/rte_flow.rst
> > index b305a72..7417833 100644
> > --- a/doc/guides/prog_guide/rte_flow.rst
> > +++ b/doc/guides/prog_guide/rte_flow.rst
> > @@ -1969,112 +1969,95 @@ Implements ``OFPAT_PUSH_MPLS`` ("push a
> new MPLS tag") as defined by the
> >     | ``ethertype`` | EtherType |
> >     +---------------+-----------+
> >
> > -Action: ``VXLAN_ENCAP``
> > -^^^^^^^^^^^^^^^^^^^^^^^
> > -
> > -Performs a VXLAN encapsulation action by encapsulating the matched
> flow in the
> > -VXLAN tunnel as defined in the``rte_flow_action_vxlan_encap`` flow
> items
> > -definition.
> > +Action: ``TUNNEL_ENCAP``
> > +^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > -This action modifies the payload of matched flows. The flow definition
> specified
> > -in the ``rte_flow_action_tunnel_encap`` action structure must define a
> valid
> > -VLXAN network overlay which conforms with RFC 7348 (Virtual eXtensible
> Local
> > -Area Network (VXLAN): A Framework for Overlaying Virtualized Layer 2
> Networks
> > -over Layer 3 Networks). The pattern must be terminated with the
> > -RTE_FLOW_ITEM_TYPE_END item type.
> > +Perform a tunnel encapsulation action by encapsulating the matched flow
> with
> > +the given buffer.
> >
> > -.. _table_rte_flow_action_vxlan_encap:
> > +This action modifies the payload of the matched flows.
> > +The buffer must hold a valid tunnel encapsulation header.
> >
> > -.. table:: VXLAN_ENCAP
> > +.. _table_rte_flow_action_tunnel_encap:
> >
> > +.. table:: TUNNEL_ENCAP
> > +
> >     +----------------+-------------------------------------+
> >     | Field          | Value                               |
> >
> +================+=====================================+
> > -   | ``definition`` | Tunnel end-point overlay definition |
> > +   | ``type``       | Encapsulation tunnel type.          |
> > +   +----------------+-------------------------------------+
> > +   | ``buf``        | The encapsulation header.           |
> > +   +----------------+-------------------------------------+
> > +   | ``len``        | Buf len.                            |
> >     +----------------+-------------------------------------+
> >
> > -.. _table_rte_flow_action_vxlan_encap_example:
> > -
> > -.. table:: IPv4 VxLAN flow pattern example.
> > -
> > -   +-------+----------+
> > -   | Index | Item     |
> > -   +=======+==========+
> > -   | 0     | Ethernet |
> > -   +-------+----------+
> > -   | 1     | IPv4     |
> > -   +-------+----------+
> > -   | 2     | UDP      |
> > -   +-------+----------+
> > -   | 3     | VXLAN    |
> > -   +-------+----------+
> > -   | 4     | END      |
> > -   +-------+----------+
> > -
> > -Action: ``VXLAN_DECAP``
> > -^^^^^^^^^^^^^^^^^^^^^^^
> > +Action: ``TUNNEL_DECAP``
> > +^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > -Performs a decapsulation action by stripping all headers of the VXLAN
> tunnel
> > -network overlay from the matched flow.
> > +Perform a tunnel decapsulation on L2 inner packet
> >
> > -The flow items pattern defined for the flow rule with which a
> ``VXLAN_DECAP``
> > -action is specified, must define a valid VXLAN tunnel as per RFC7348. If the
> > -flow pattern does not specify a valid VXLAN tunnel then a
> > -RTE_FLOW_ERROR_TYPE_ACTION error should be returned.
> > +This action modifies the payload of the matched flows.
> > +The buffer must hold a valid tunnel encapsulation header.
> >
> > -This action modifies the payload of matched flows.
> > +.. _table_rte_flow_action_tunnel_decap:
> >
> > -Action: ``NVGRE_ENCAP``
> > -^^^^^^^^^^^^^^^^^^^^^^^
> > +.. table:: TUNNEL_DECAP
> > +
> > +   +----------------+-------------------------------------+
> > +   | Field          | Value                               |
> > +
> +================+=====================================+
> > +   | ``type``       | Encapsulation tunnel type.          |
> > +   +----------------+-------------------------------------+
> >
> > -Performs a NVGRE encapsulation action by encapsulating the matched
> flow in the
> > -NVGRE tunnel as defined in the``rte_flow_action_tunnel_encap`` flow
> item
> > -definition.
> > +Action: ``TUNNEL_ENCAP_L3``
> > +^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > -This action modifies the payload of matched flows. The flow definition
> specified
> > -in the ``rte_flow_action_tunnel_encap`` action structure must defined a
> valid
> > -NVGRE network overlay which conforms with RFC 7637 (NVGRE: Network
> > -Virtualization Using Generic Routing Encapsulation). The pattern must be
> > -terminated with the RTE_FLOW_ITEM_TYPE_END item type.
> > +Perform a tunnel encapsulation action by encapsulating the matched flow
> with
> > +the given buffer.
> > +The given encapsulation is overwritten the original L2 part of the original
> > +packet.
> >
> > -.. _table_rte_flow_action_nvgre_encap:
> > +This action modifies the payload of the matched flows. The buffer must
> hold
> > +a valid tunnel encapsulation header.
> >
> > -.. table:: NVGRE_ENCAP
> > +.. _table_rte_flow_action_tunnel_encap_l3:
> >
> > +.. table:: TUNNEL_ENCAP_L3
> > +
> >     +----------------+-------------------------------------+
> >     | Field          | Value                               |
> >
> +================+=====================================+
> > -   | ``definition`` | NVGRE end-point overlay definition  |
> > +   | ``type``       | Encapsulation tunnel type.          |
> > +   +----------------+-------------------------------------+
> > +   | ``buf``        | The encapsulation header.           |
> > +   +----------------+-------------------------------------+
> > +   | ``len``        | Buf len.                            |
> >     +----------------+-------------------------------------+
> >
> > -.. _table_rte_flow_action_nvgre_encap_example:
> > -
> > -.. table:: IPv4 NVGRE flow pattern example.
> > -
> > -   +-------+----------+
> > -   | Index | Item     |
> > -   +=======+==========+
> > -   | 0     | Ethernet |
> > -   +-------+----------+
> > -   | 1     | IPv4     |
> > -   +-------+----------+
> > -   | 2     | NVGRE    |
> > -   +-------+----------+
> > -   | 3     | END      |
> > -   +-------+----------+
> > +Action: ``TUNNEL_DECAP_L3``
> > +^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > -Action: ``NVGRE_DECAP``
> > -^^^^^^^^^^^^^^^^^^^^^^^
> > +Perform a tunnel decapsulation action by removing the encapsulating
> packet header
> > +and adding the L2 header which is suplied in the buf parameter.
> >
> > -Performs a decapsulation action by stripping all headers of the NVGRE
> tunnel
> > -network overlay from the matched flow.
> > +This action modifies the payload of the matched flows.
> > +The buffer must hold a valid L2 header and the flow must match patteran
> with the
> > +selected tunnel type.
> >
> > -The flow items pattern defined for the flow rule with which a
> ``NVGRE_DECAP``
> > -action is specified, must define a valid NVGRE tunnel as per RFC7637. If the
> > -flow pattern does not specify a valid NVGRE tunnel then a
> > -RTE_FLOW_ERROR_TYPE_ACTION error should be returned.
> > +.. _table_rte_flow_action_tunnel_decap_l3:
> >
> > -This action modifies the payload of matched flows.
> > +.. table:: TUNNEL_DECAP_L3
> > +
> > +   +----------------+-------------------------------------+
> > +   | Field          | Value                               |
> > +
> +================+=====================================+
> > +   | ``type``       | Encapsulation tunnel type.          |
> > +   +----------------+-------------------------------------+
> > +   | ``buf``        | The encapsulation header.           |
> > +   +----------------+-------------------------------------+
> > +   | ``len``        | Buf len.                            |
> > +   +----------------+-------------------------------------+
> >
> >  Negative types
> >  ~~~~~~~~~~~~~~
> > diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
> > index f8ba71c..cc01786 100644
> > --- a/lib/librte_ethdev/rte_flow.h
> > +++ b/lib/librte_ethdev/rte_flow.h
> > @@ -1473,40 +1473,74 @@ enum rte_flow_action_type {
> >  	RTE_FLOW_ACTION_TYPE_OF_PUSH_MPLS,
> >
> >  	/**
> > -	 * Encapsulate flow in VXLAN tunnel as defined in
> > -	 * rte_flow_action_vxlan_encap action structure.
> > + 	 * Encapsulte a packet with tunnel header.
> > + 	 *
> > + 	 * See struct rte_flow_action_tunnel_encap.
> > + 	 */
> > +	RTE_FLOW_ACTION_TYPE_TUNNEL_ENCAP,
> > +
> > +	/**
> > + 	 * Encapsulte a packet with tunnel header replacing
> > + 	 * the inner L2 data.
> > + 	 *
> > + 	 * See struct rte_flow_action_tunnel_encap_l3.
> > + 	 */
> > +	RTE_FLOW_ACTION_TYPE_TUNNEL_ENCAP_L3,
> > +
> > +	/**
> > +	 * Decapsulate outer most tunnel from matched flow.
> >  	 *
> > -	 * See struct rte_flow_action_vxlan_encap.
> > +	 * If flow pattern does not define a valid tunnel then
> > +	 * the PMD should return a RTE_FLOW_ERROR_TYPE_ACTION
> > +	 * error.
> >  	 */
> > -	RTE_FLOW_ACTION_TYPE_VXLAN_ENCAP,
> > +	RTE_FLOW_ACTION_TYPE_TUNNEL_DECAP,
> >
> >  	/**
> > -	 * Decapsulate outer most VXLAN tunnel from matched flow.
> > +	 * Decapsulate outer most tunnel from matched flow and replace
> > +	 * the L2 header with the new header.
> > +	 * Valid header must be L2 only.
> >  	 *
> > -	 * If flow pattern does not define a valid VXLAN tunnel (as specified
> by
> > -	 * RFC7348) then the PMD should return a
> RTE_FLOW_ERROR_TYPE_ACTION
> > +	 * If flow pattern does not define a valid tunnel then
> > +	 * the PMD should return a RTE_FLOW_ERROR_TYPE_ACTION
> >  	 * error.
> > +	 *
> > +	 * See struct rte_flow_action_tunnel_decap_l3
> >  	 */
> > -	RTE_FLOW_ACTION_TYPE_VXLAN_DECAP,
> > +	RTE_FLOW_ACTION_TYPE_TUNNEL_DECAP_L3,
> > +};
> >
> > +enum rte_flow_tunnel_type {
> >  	/**
> > -	 * Encapsulate flow in NVGRE tunnel defined in the
> > -	 * rte_flow_action_nvgre_encap action structure.
> > -	 *
> > -	 * See struct rte_flow_action_nvgre_encap.
> > +	 * VXLAN tunnel type.
> >  	 */
> > -	RTE_FLOW_ACTION_TYPE_NVGRE_ENCAP,
> > +	RTE_FLOW_TUNNEL_TYPE_VXLAN,
> >
> >  	/**
> > -	 * Decapsulate outer most NVGRE tunnel from matched flow.
> > -	 *
> > -	 * If flow pattern does not define a valid NVGRE tunnel (as specified
> by
> > -	 * RFC7637) then the PMD should return a
> RTE_FLOW_ERROR_TYPE_ACTION
> > -	 * error.
> > +	 * VXLAN_GPE tunnel type.
> >  	 */
> > -	RTE_FLOW_ACTION_TYPE_NVGRE_DECAP,
> > -};
> > +	RTE_FLOW_TUNNEL_TYPE_VXLAN_GPE,
> >
> > +	/**
> > +	 * MPLSoGRE tunnel type.
> > +	 */
> > +	RTE_FLOW_TUNNEL_TYPE_MPLSoGRE,
> > +
> > +	/**
> > +	 * MPLSoUDP tunnel type.
> > +	 */
> > +	RTE_FLOW_TUNNEL_TYPE_MPLSoUDP,
> > +
> > +	/**
> > +	 * NVGRE tunnel type.
> > +	 */
> > +	RTE_FLOW_TUNNEL_TYPE_NVGRE,
> > +
> > +	/**
> > +	 * GRE tunnel type.
> > +	 */
> > +	RTE_FLOW_TUNNEL_TYPE_GRE,
> > +};
> >  /**
> >   * RTE_FLOW_ACTION_TYPE_MARK
> >   *
> > @@ -1526,7 +1560,7 @@ struct rte_flow_action_mark {
> >   * @b EXPERIMENTAL: this structure may change without prior notice
> >   *
> >   * RTE_FLOW_ACTION_TYPE_JUMP
> > - *
> > + o*
> >   * Redirects packets to a group on the current device.
> >   *
> >   * In a hierarchy of groups, which can be used to represent physical or
> logical
> > @@ -1803,69 +1837,68 @@ struct rte_flow_action_of_push_mpls {
> >   * @warning
> >   * @b EXPERIMENTAL: this structure may change without prior notice
> >   *
> > - * RTE_FLOW_ACTION_TYPE_VXLAN_ENCAP
> > - *
> > - * VXLAN tunnel end-point encapsulation data definition
> > + * RTE_FLOW_ACTION_TYPE_TUNNEL_ENCAP
> >   *
> > - * The tunnel definition is provided through the flow item pattern, the
> > - * provided pattern must conform to RFC7348 for the tunnel specified. The
> flow
> > - * definition must be provided in order from the
> RTE_FLOW_ITEM_TYPE_ETH
> > - * definition up the end item which is specified by
> RTE_FLOW_ITEM_TYPE_END.
> > + * Tunnel end-point encapsulation data definition.
> >   *
> > - * The mask field allows user to specify which fields in the flow item
> > - * definitions can be ignored and which have valid data and can be used
> > - * verbatim.
> > - *
> > - * Note: the last field is not used in the definition of a tunnel and can be
> > - * ignored.
> > + * The tunnel definition is provided through the use of buffer that
> > + * holds the encapsulating header.
> > + * Provided header must be a valid outer tunnel header.
> > + */
> > +struct rte_flow_action_tunnel_encap {
> > +	enum rte_flow_tunnel_type type; /**< The tunnel type. */
> > +	void *buf; /**< The header to be used. */
> > +	uint32_t len; /**< The buf len. */
> > +};
> > +
> > +/**
> > + * @warning
> > + * @b EXPERIMENTAL: this structure may change without prior notice
> >   *
> > - * Valid flow definition for RTE_FLOW_ACTION_TYPE_VXLAN_ENCAP
> include:
> > + * RTE_FLOW_ACTION_TYPE_TUNNEL_DECAP
> >   *
> > - * - ETH / IPV4 / UDP / VXLAN / END
> > - * - ETH / IPV6 / UDP / VXLAN / END
> > - * - ETH / VLAN / IPV4 / UDP / VXLAN / END
> > + * Tunnel end-point dencapsulation data definition.
> >   *
> > + * The tunnel type must match the flow rule spec.
> >   */
> > -struct rte_flow_action_vxlan_encap {
> > -	/**
> > -	 * Encapsulating vxlan tunnel definition
> > -	 * (terminated by the END pattern item).
> > -	 */
> > -	struct rte_flow_item *definition;
> > +struct rte_flow_action_tunnel_decap {
> > +	enum rte_flow_tunnel_type type; /**< The tunnel type. */
> >  };
> >
> >  /**
> >   * @warning
> >   * @b EXPERIMENTAL: this structure may change without prior notice
> >   *
> > - * RTE_FLOW_ACTION_TYPE_NVGRE_ENCAP
> > - *
> > - * NVGRE tunnel end-point encapsulation data definition
> > - *
> > - * The tunnel definition is provided through the flow item pattern  the
> > - * provided pattern must conform with RFC7637. The flow definition must
> be
> > - * provided in order from the RTE_FLOW_ITEM_TYPE_ETH definition up
> the end item
> > - * which is specified by RTE_FLOW_ITEM_TYPE_END.
> > + * RTE_FLOW_ACTION_TYPE_TUNNEL_ENCAP_L3
> >   *
> > - * The mask field allows user to specify which fields in the flow item
> > - * definitions can be ignored and which have valid data and can be used
> > - * verbatim.
> > + * Tunnel end-point encapsulation over the inner L2 data definition.
> >   *
> > - * Note: the last field is not used in the definition of a tunnel and can be
> > - * ignored.
> > + * The tunnel definition is provided through the use of buffer that
> > + * holds the encapsulating header.
> > + * Provided header must be a valid outer tunnel header.
> > + */
> > +struct rte_flow_action_tunnel_encap_l3 {
> > +	enum rte_flow_tunnel_type type; /**< The tunnel type. */
> > +	void *buf; /**< The header to be used. */
> > +	uint32_t len; /**< The buf len. */
> > +};
> > +
> > +/**
> > + * @warning
> > + * @b EXPERIMENTAL: this structure may change without prior notice
> >   *
> > - * Valid flow definition for RTE_FLOW_ACTION_TYPE_NVGRE_ENCAP
> include:
> > + * RTE_FLOW_ACTION_TYPE_TUNNEL_DECAP_L3
> >   *
> > - * - ETH / IPV4 / NVGRE / END
> > - * - ETH / VLAN / IPV6 / NVGRE / END
> > + * Tunnel end-point dencapsulation data definition.
> > + * after the decapsulation, the L2 of the resulted packet
> > + * is replaced with the supplied buffer.
> >   *
> > + * The tunnel type must match the flow rule spec.
> >   */
> > -struct rte_flow_action_nvgre_encap {
> > -	/**
> > -	 * Encapsulating vxlan tunnel definition
> > -	 * (terminated by the END pattern item).
> > -	 */
> > -	struct rte_flow_item *definition;
> > +struct rte_flow_action_tunnel_decap_l3 {
> > +	enum rte_flow_tunnel_type type; /**< The tunnel type. */
> > +	void *buf; /**< The L2 header to be used.*/
> > +	uint32_t len; /**< The len of the buf. */
> >  };
> >
> >  /*
> > --
> > 1.7.1
> >
> 
> [1]
> https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdpd
> k.org%2Fdev%2Fpatchwork%2Fpatch%2F40965%2F&data=02%7C01%7Corika
> %40mellanox.com%7C371fe1d7e25544903bc008d5cf680813%7Ca652971c7d2
> e4d9ba6a4d149256f461b%7C0%7C0%7C636642968087329644&sdata=gChSJ2g
> ypLJNQuWrui2aBtw1364RucnaT5hAj6WRNb4%3D&reserved=0
> 
> --
> Nélio Laranjeiro
> 6WIND

  reply	other threads:[~2018-06-11  7:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-05 15:48 Ori Kam
2018-06-11  6:53 ` Nélio Laranjeiro
2018-06-11  7:27   ` Ori Kam [this message]
2018-06-11  7:53     ` Nélio Laranjeiro
2018-06-11 10:46 ` [dpdk-dev] [RFC v2] ethdev: support MPLS " Ori Kam
2018-06-11 11:03 ` [dpdk-dev] [RFC] ethdev: support " Ori Kam
2018-06-11 11:20   ` Thomas Monjalon

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