Re: [DMAPI] code error in dm_ip_to_handle()

[Aurelien Degremont - Stagiaire <degremont@xxxxxxxxxxx>]

> The dm_fid_len field is used to distinguish between filesystem handles and
> file handles.  That has to stay in place.

Ok. I miss this.
About it, I don't understand how the dm_fid_len is filled. I don't find 
where in the code, you set its len to 0 when its a filesystem handle ? 
How do you know this ?

(But I found in xfs_dm_fh_to_inode(), where you test the fid_len)

> > The question is : Does DMAPI need the inode number of the filehandles ?
> > After some searches it seems this data is only used in dmapi_session.c, 
> > when dealing with hash_event. I don't know the purpose of them. But 
> > concerning repeated_event(), it looks like the inode number is only used 
> > in order to compare 2 handles. I think, this comparison must be done 
> > using the whole structure (memcmp) or at least using the ino AND the gen 
> > number. The ino number is not enough.

> I could agree to that, but what do we give to the hash function?

I don't know the purpose of this hash function, so i couldn't help you 
here. But, at least, check also the i_gen number equality, or do a 
memcmp() between the two handle structures rather then just the ino value.

> It is the FS which must convert between handles and filesystem objects, so the
> handle better make sense to the FS.  Whenever DMAPI needs this conversion, it
> should call to the FS.  So, no, DMAPI should not control the 'dm_fid_ino'
> field.

Ok, so let the FS free of whatever tricks it wants or needs (thinking 
about distributed filesystem by example...)


Ok. So, do we remove the dm_fsfid_t ? Replace it by a dm_fid as you 
proposed ? I think it's a good idea.


Aurelien