Re: [PATCH v7 0/7] Add O_DENY* support for VFS and CIFS/NFS

[Pavel Shilovsky]

2014/1/17 Frank Filz :
> This looks wonderful and will be useful to the Ganesha user space NFS server
> also.
>
> I do have a couple questions.
> - How will this interact with the idea of private locks from the patch set
>
> Jeff Layton has been pushing?

They don't touch each other.
> - If a process opens multiple file descriptors with deny modes, will they
>
> conflict with each other (which is the behavior we will want for Ganesha).

Yes, a deny mode is associated with file descriptor - so, it will
conflict with any other access/deny modes of file descriptors from any
process.
> - Is there any functionality to upgrade or downgrade the access and deny
>
> modes (thinking in terms of NFS v4 support of OPEN upgrade and
> OPEN_DOWNGRADE operations).

The proposed patchset doesn't allow to change deny modes after an open
is done. But we can add a functionality to let flock syscall change
deny modes as on option.