OpenSM SRIOV (Alias GUID) Support

12/9/11

Overview

In order to support virtualized environments, alias GUID support is added to OpenSM.

This support allows an SA client to add and remove additional port GUIDs based on

SubAdmSet/SubAdmDelete of GUIDInfoRecord. A set with a GUID of 0 in a valid GUIDInfoRecord

index as indicated by the component mask indicates that the additional GUID is to

be SM assigned. The OpenIB OUI (0x001405), along with a configured byte and a

pseudorandom number is currently used for this algorithm (which may be changed in the future).

Most SA queries are updated to handle alias GUIDs as part of any GID specified inside

the query. These include SA path record, multipath record, multicast record, and service record.

There are only a few SA queries (InformInfoRecord, InformInfo) that are not currently updated

for alias GUID support.

In terms of the IBA spec, alias GUIDs are termed additional port GUIDs.

IBA 1.2.1 Volume 1 Changes for Alias GUID Support

The following are MgtWG WG APPROVED spec changes to IBA 1.2.1 volume 1 relative to this support:

RefID 4704

15.2.5.18 GUIDInfoRecord p. 932 line 14

Table 213 GUIDInfoRecord

An entity that wishes to add or remove additional port GUIDs can do so using the SubnAdmSet() and SubnAdmDelete() methods

with the GUIDInfoRecord attribute. This causes the SM to set the updated GUIDs in the specified port via the SM GUIDInfo attribute.

SubnAdmSet() method is used to add additional port GUIDs. SubnAdmDelete() method is used to remove previously added additional

port GUIDs.

o15-0.x.y: If SA supports additional port GUIDs, then both SubAdmSet(GUIDInfoRecord) and SubnAdmDelete(GUIDInfoRecord) are

supported.

o15-0.x.y: If SA supports additional port GUIDs, the component mask for SubAdmSet(GUIDInfoRecord) and

SubnAdmDelete(GUIDInfoRecord) is required to include both LID and block number. If the component mask does not include both of

these, SA shall return an error status of ERR_REQ_INSUFFICIENT_COMPONENTS in its response to the corresponding method.

o15-0.x.y: If SA supports additional port GUIDs, for a SubAdmSet(GUIDInfoRecord), the component mask indicates which GUID indices

are to be set. A GUID can either be added or replaced. A GUID of 0 indicates that the GUID for this index is to be assigned by

the SM.

o15-0.x.y: If SA supports additional port GUIDs, for a SubAdmDelete(GUIDInfoRecord), the component mask indicates which GUID

indices are to be removed.

o15-0.x.y: If SA supports additional port GUIDs, the SA shall return an error status of ERR_REQ_INVALID to any attempt to set

or delete block number 0 index 0.

RefID 4705

p.899 line 26 15.2.4

Table 188 SA-Specific Optional Capabilities

<add table entry:>

IsAdditionalGUIDsSupported | CM2 | 5 | If this value is 1, SA shall support the ability to add and remove additional port GUIDs

                                       via SubAdmSet/SubnAdmDelete(GUIDInfoRecord) as described in

                                       <ref to 15.2.5.18 GUIDInfoRecord>

RefID 4706

p.904 line 21 15.2.5.1

Table 192 Subnet Administration Attribute / Method Map

<Add an "X" to the "Set" and "Delete" columns for GUIDInfoRecord>

<Add footnote "b" to GUIDInfoRecord where footnote "b" is as shown below:>

b: SubAdmSet and SubAdmDelete of GUIDInfoRecord are supported if SA:ClassPortInfo.CapabilityMask2 indicates

IsAdditionalGUIDsSupported.

RefID 4714

Clarify GUID 0 in SA Set GUIDInfoRecord response

p.932 line 14 15.2.18

<change:>

o15-0.x.y: If SA supports additional port GUIDs, for a SubAdmSet(GUIDInfoRecord), the component mask indicates which GUID indices

are to be set. A GUID can either be added or replaced. A GUID of 0 indicates that the GUID for this index is to be assigned by

the SM.

<to:>

o15-0.x.y: If SA supports additional port GUIDs, for a SubAdmSet(GUIDInfoRecord), the component mask indicates which GUID indices

are to be set. A GUID can either be added or replaced. In the request, a GUID of 0 indicates that the GUID for this index is to

be assigned by the SM. In the response, a GUID of 0 indicates that the GUID requested for this index was not accepted by the SA.

RefID 4776

SM GUIDInfo initialization

<change:>

GUIDInfo Description

The requirements for setting additional

GUIDs are beyond the scope of the specification.

<to:>

<none>

OpenSM SRIOV Configuration

Some new options were added for SRIOV configuration of OpenSM.

1. Allow both pkeys

-W or --allow_both_pkeys on the command line or

allow_both_pkeys TRUE

in the options file. Default is false.

allow_both_pkeys indicates whether both full and

limited membership on the same partition is allowed or not.

In order to support allow_both_pkeys, the partition file syntax is

extended with "both" flag (in addition to "full" and "limited").

defmember=full|limited|both

or

[PortGUID[=full|=limited|=both]]

2. SM assigned GUID byte

sm_assigned_guid

in the options file. Default is 0.

An SM assigned GUID byte is added as a configuration option

where an alias GUID is formed from OpenFabrics OUI

followed by 40 bits xy 00 ab cd ef where xy is the SM assigned guid byte

and ab cd ef is an SM autogenerated 24 bits.

The SM assigned GUID byte should be configured as subnet unique.

Also, the algorithm to obtain a "unique" SM assigned GUID is changing from

being based on a static monatomically incrementing counter for the SM

autogenerated part (like SA MCMemberRecord SM assigned MGIDs).

The number of retries to find an unused GUID is currently hardcoded at 1000.

Note that it is not a current requirement to maintain SM assigned GUIDs across OpenSM

failover. Note also that on reregistration, a host may reregister the previously SM

assigned GUID.

Operational Notes

Duplicated alias GUIDs are detected against alias and physical GUIDs and result in

rejection of such registrations.

When a port is dropped, any alias GUID registrations are removed. These are

reregistered by client reregistration mechanism. The exception

to this is service registrations as these are not currently reregistered by

the ULPs/applications that use them.

Futures

1. An alias GUID enforcement feature to which physical ports are allowed to request which

alias GUIDs.