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diff --git a/Documentation/infiniband/opa_vnic.txt b/Documentation/infiniband/opa_vnic.txt deleted file mode 100644 index 282e17be798a..000000000000 --- a/Documentation/infiniband/opa_vnic.txt +++ /dev/null @@ -1,153 +0,0 @@ -Intel Omni-Path (OPA) Virtual Network Interface Controller (VNIC) feature -supports Ethernet functionality over Omni-Path fabric by encapsulating -the Ethernet packets between HFI nodes. - -Architecture -============= -The patterns of exchanges of Omni-Path encapsulated Ethernet packets -involves one or more virtual Ethernet switches overlaid on the Omni-Path -fabric topology. A subset of HFI nodes on the Omni-Path fabric are -permitted to exchange encapsulated Ethernet packets across a particular -virtual Ethernet switch. The virtual Ethernet switches are logical -abstractions achieved by configuring the HFI nodes on the fabric for -header generation and processing. In the simplest configuration all HFI -nodes across the fabric exchange encapsulated Ethernet packets over a -single virtual Ethernet switch. A virtual Ethernet switch, is effectively -an independent Ethernet network. The configuration is performed by an -Ethernet Manager (EM) which is part of the trusted Fabric Manager (FM) -application. HFI nodes can have multiple VNICs each connected to a -different virtual Ethernet switch. The below diagram presents a case -of two virtual Ethernet switches with two HFI nodes. - - +-------------------+ - | Subnet/ | - | Ethernet | - | Manager | - +-------------------+ - / / - / / - / / - / / -+-----------------------------+ +------------------------------+ -| Virtual Ethernet Switch | | Virtual Ethernet Switch | -| +---------+ +---------+ | | +---------+ +---------+ | -| | VPORT | | VPORT | | | | VPORT | | VPORT | | -+--+---------+----+---------+-+ +-+---------+----+---------+---+ - | \ / | - | \ / | - | \/ | - | / \ | - | / \ | - +-----------+------------+ +-----------+------------+ - | VNIC | VNIC | | VNIC | VNIC | - +-----------+------------+ +-----------+------------+ - | HFI | | HFI | - +------------------------+ +------------------------+ - - -The Omni-Path encapsulated Ethernet packet format is as described below. - -Bits Field ------------------------------------- -Quad Word 0: -0-19 SLID (lower 20 bits) -20-30 Length (in Quad Words) -31 BECN bit -32-51 DLID (lower 20 bits) -52-56 SC (Service Class) -57-59 RC (Routing Control) -60 FECN bit -61-62 L2 (=10, 16B format) -63 LT (=1, Link Transfer Head Flit) - -Quad Word 1: -0-7 L4 type (=0x78 ETHERNET) -8-11 SLID[23:20] -12-15 DLID[23:20] -16-31 PKEY -32-47 Entropy -48-63 Reserved - -Quad Word 2: -0-15 Reserved -16-31 L4 header -32-63 Ethernet Packet - -Quad Words 3 to N-1: -0-63 Ethernet packet (pad extended) - -Quad Word N (last): -0-23 Ethernet packet (pad extended) -24-55 ICRC -56-61 Tail -62-63 LT (=01, Link Transfer Tail Flit) - -Ethernet packet is padded on the transmit side to ensure that the VNIC OPA -packet is quad word aligned. The 'Tail' field contains the number of bytes -padded. On the receive side the 'Tail' field is read and the padding is -removed (along with ICRC, Tail and OPA header) before passing packet up -the network stack. - -The L4 header field contains the virtual Ethernet switch id the VNIC port -belongs to. On the receive side, this field is used to de-multiplex the -received VNIC packets to different VNIC ports. - -Driver Design -============== -Intel OPA VNIC software design is presented in the below diagram. -OPA VNIC functionality has a HW dependent component and a HW -independent component. - -The support has been added for IB device to allocate and free the RDMA -netdev devices. The RDMA netdev supports interfacing with the network -stack thus creating standard network interfaces. OPA_VNIC is an RDMA -netdev device type. - -The HW dependent VNIC functionality is part of the HFI1 driver. It -implements the verbs to allocate and free the OPA_VNIC RDMA netdev. -It involves HW resource allocation/management for VNIC functionality. -It interfaces with the network stack and implements the required -net_device_ops functions. It expects Omni-Path encapsulated Ethernet -packets in the transmit path and provides HW access to them. It strips -the Omni-Path header from the received packets before passing them up -the network stack. It also implements the RDMA netdev control operations. - -The OPA VNIC module implements the HW independent VNIC functionality. -It consists of two parts. The VNIC Ethernet Management Agent (VEMA) -registers itself with IB core as an IB client and interfaces with the -IB MAD stack. It exchanges the management information with the Ethernet -Manager (EM) and the VNIC netdev. The VNIC netdev part allocates and frees -the OPA_VNIC RDMA netdev devices. It overrides the net_device_ops functions -set by HW dependent VNIC driver where required to accommodate any control -operation. It also handles the encapsulation of Ethernet packets with an -Omni-Path header in the transmit path. For each VNIC interface, the -information required for encapsulation is configured by the EM via VEMA MAD -interface. It also passes any control information to the HW dependent driver -by invoking the RDMA netdev control operations. - - +-------------------+ +----------------------+ - | | | Linux | - | IB MAD | | Network | - | | | Stack | - +-------------------+ +----------------------+ - | | | - | | | - +----------------------------+ | - | | | - | OPA VNIC Module | | - | (OPA VNIC RDMA Netdev | | - | & EMA functions) | | - | | | - +----------------------------+ | - | | - | | - +------------------+ | - | IB core | | - +------------------+ | - | | - | | - +--------------------------------------------+ - | | - | HFI1 Driver with VNIC support | - | | - +--------------------------------------------+ |