On Mon 16-10-17 00:45:04, Christoph Hellwig wrote:

quoted

How about the following incremental update? It allows ->mmap_validate()
to be used as a full replacement for ->mmap() and it limits the error
code freedom to a centralized mmap_status_errno() routine:

Nah - my earlier comment was simply misinformed because I didn't
read the whole patch and the _validate name mislead me.

So I think the current calling conventions are ok, I'd just like a
better name (mmap_flags maybe?) and avoid the need the file system
also has to implement ->mmap.

OK, I can do that. But I had just realized that if MAP_DIRECT isn't going
to end up using mmap(2) interface but something else (and I'm not sure
where discussions on this matter ended), we don't need flags argument for
->mmap at all. MAP_SYNC uses a VMA flag anyway and thus it is fine with the
current ->mmap interface. We still need some opt-in mechanism for
MAP_SHARED_VALIDATE though (probably supported mmap flags as Dan had in one
version of his patch). Thoughts on which way to go for now?

								Honza
-- 
Jan Kara [off-list ref]
SUSE Labs, CR