Some deficiencies with the Samba VFS that I think need to e rectified ...

[Jon Knight]

On Tue, 10 Dec 2013, Richard Sharpe wrote:
> I have written before about wanting all VFS functions to return NT
> Status codes and the fact that the dir related functions do not
> provide something like an FSP, however, one more deficiency has become
> apparent as we get more into distributed systems at my place of
> employment.
>
> That is, we do not have sufficient information to make correct
> decisions during some metadata operations. Specifically, when mkdir
> and open are called, we really need access to fields like access_mask
> and share_mode ...
>
> I wonder if it would be appropriate, early on in CreateFile, to create
> the FSP and pre-load it with these values so we can pass along an FSP
> to all operations that are not path-based?

In the VFS module we've been working on recently we've salted extra 
information away in the fsp during the create_file() VFS call using the 
VFS_ADD_FSP_EXTENSION() macro.  This lets us pass information that isn't 
in POSIX into other VFS calls (in our case its a string representation of 
the ID of the file that's been created in the remote file store which is 
needed when the file is closed and/or deleted as we need to replicate 
cache local state changes back to the remote file store).