Re: Fwd: Re: [PATCH] libibmad: To reserve upper 8 bits of tid used by solaris SRIOV driver

[Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>]

On Thu, Mar 21, 2013 at 06:14:47PM +0000, brendan doyle wrote:
> Ok so I think we are essentially on the same page...
> 
> >This is already the case, only the lower 32 bits are available for
> >application use, the upper 32 bits are all reserved for the kernel,

> This is not an IB spec defined delineation, but an OF one. Perhaps
> there was some community discussion to architect it this way but it
> is not documented. At the very least this patch should document
> this.

Well, it is how /dev/umad works - IBA does not define the umad api,
Solaris is copying the Linux umad API, so it should work the same..

There is no need to specify the format of the upper 32 bits, it is
kernel specific and has no impact on the application. The kernel
should use those bits as necessary to demux flows between users of
umad, be they processes or VMs.

> So how about modifying the patch such that mad_trid() is something like:

Looks like a reasonable clarification of existing usage to me.

Jason
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