[openib-general] netdev reference counting problem with ib_at

[Sean Hefty]

Hal Rosenstock wrote:
>>    Sean> I continue to hit this same issue, so I've started looking
>>    Sean> at the ib_at code. Ib_at accesses struct ipoib_dev_priv to
>>    Sean> get information about the related port that IPoIB is using.
>>    Sean> Is there some other way for AT to get to the same
>>    Sean> information?  It seems wrong for AT to poke into the priv
>>    Sean> data of a net_device. Should IPoIB expose a function that AT
>>    Sean> can call to map IP addresses (or net_device) to IB ports?
>>    Sean> How do we want to handle this long term?
>>
>>It probably makes sense to add an ib_ptr (or rdma_ptr) to struct
>>net_device (along with all the other ones like ip_ptr, dn_ptr,
>>ax25_ptr, etc).
> 
> 
> Is this ib_ptr or ipoib_ptr ? I would think iWARP devices would need
> this.

I think that we can implement the CMA interface without adding this pointer by 
using ARP and the private data in the CM REQ.  Is it needed for any other purpose?

- Sean