• Hiral Patel's avatar
    [SCSI] fnic: FIP VLAN Discovery Feature Support · d3c995f1
    Hiral Patel authored
    FIP VLAN discovery discovers the FCoE VLAN that will be used by all other FIP
    protocols as well as by the FCoE encapsulation for Fibre Channel payloads on
    the established virtual link. One of the goals of FC-BB-5 was to be as
    nonintrusive as possible on initiators and targets, and therefore FIP VLAN
    discovery occurs in the native VLAN used by the initiator or target to
    exchange Ethernet traffic. The FIP VLAN discovery protocol is the only FIP
    protocol running on the native VLAN; all other FIP protocols run on the
    discovered FCoE VLANs.
    
    If an administrator has manually configured FCoE VLANs on ENodes and FCFs,
    there is no need to use this protocol. FIP and FCoE will run over the
    configured VLANs.
    
    An ENode without FCoE VLANs configuration would use this automated discovery
    protocol to discover over which VLANs FCoE is running.
    
    The ENode sends a FIP VLAN discovery request to a multicast MAC address called
    All-FCF-MACs, which is a multicast MAC address to which all FCFs listen.
    
    All FCFs that can be reached in the native VLAN of the ENode are expected to
    respond on the same VLAN with a response that lists one or more FCoE VLANs
    that are available for the ENode's VN_Port login. This protocol has the sole
    purpose of allowing the ENode to discover all the available FCoE VLANs.
    
    Now the ENode may enable a subset of these VLANs for FCoE Running the FIP
    protocol in these VLANs on a per VLAN basis. And FCoE data transactions also
    would occur on this VLAN. Hence, Except for FIP VLAN discovery, all other FIP
    and FCoE traffic runs on the selected FCoE VLAN.  Its only the FIP VLAN
    Discovery protocol that is permitted to run on the Default native VLAN of the
    system.
    
    [**** NOTE ****]
    We are working on moving this feature definitions and functionality to libfcoe
    module. We need this patch to be approved, as Suse is looking forward to merge
    this feature in SLES 11 SP3 release.  Once this patch is approved, we will
    submit patch which should move vlan discovery feature to libfoce.
    
    [Fengguang Wu <fengguang.wu@intel.com>: kmalloc cast removal]
    Signed-off-by: default avatarAnantha Prakash T <atungara@cisco.com>
    Signed-off-by: default avatarHiral Patel <hiralpat@cisco.com>
    Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
    d3c995f1
fnic.h 11.5 KB