[openib-general] Re: RFC userspace CMA

[Sean Hefty]

Michael S. Tsirkin wrote:
> Quoting Sean Hefty <mshefty at ichips.intel.com>:
> 
>>I considered, and continue to consider implementing on top of ucm.  The 
>>drawbacks are: it requires more kernel modules: one for the CM, one for SA 
>>query, and one for address translation.
> 
> 
> Cant address translation be done with exiting kernel/user interface?

There's no kernel/user interface for ib_addr, which is what the kernel CMA uses. 
  To use the ib_at kernel/user interface, ib_at would need to be fixed to avoid 
crashing the system.  ib_addr is based off of the ib_at/sdp implementations, but 
limited to ARP translation only.

It would also require userspace components for other RDMA CMs, such as iWarp.

- Sean