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On 1/23/23 08:11, Jan Kara wrote:
>> For cifs RDMA, do I need to make it pass in FOLL_LONGTERM?  And does that need
>> a special cleanup?
> 
> FOLL_LONGTERM doesn't need a special cleanup AFAIK. It should be used
> whenever there isn't reasonably bound time after which the page is
> unpinned. So in case CIFS sets up RDMA and then it is up to userspace how
> long the RDMA is going to be running it should be using FOLL_LONGTERM. The

Yes, we have been pretty consistently deciding that RDMA generally
implies FOLL_LONGTERM. (And furthermore, FOLL_LONGTERM implies
FOLL_PIN--that one is actually enforced by the gup/pup APIs.)


thanks,
-- 
John Hubbard
NVIDIA