On Sun, Sep 12, 2010 at 12:41 AM, Rick Macklem <rmack...@uoguelph.ca> wrote:
>> Then, fid_reserved is no more reserved ? Should we rename it ?
>>
>> Comment for fid_reserved about longword alignment is wrong.
>
> Well, it's actually more broken than that.
> fid_len - Most file systems set it to the size of their variant
> of the entire structure, including the Xfid_len field.
> ZFS sets it to the size of the structure - sizeof(uint16_t)
> { presumably subtracting out the size if Xfid_len? }.
> And xfs, well, it does weird stuff with it I can't figure
> out, but it is definitely not the size of the entire struct.
>
> As such, exposing fid_len above the VOP_xxx() doesn't make much sense.
> (After my commit yesterday, nothing above the VOP_VPTOFH() uses it.)
>
> Personally, I'd lean towards a generic struct fid like...
> struct fid {
> uint8_t fid_data[MAXFIDSZ];
> };
Isilon would love a generic struct like this, as to fit our filesystem
we had to make such a change locally anyways. :-)
Cheers,
matthew
> with MAXFIDSZ increased appropriately, but this will require changes
> to xfs and zfs, since they both set the generic fid_len.
>
> If you go with...
> struct fid {
> uint16_t fid_len;
> uint8_t fid_data[MAXFIDSZ];
> };
> then the hash functions in the two NFS servers need to be changed
> (they assume 32bit alignment of fid_data), but they should be fixed
> anyhow, since they mostly hash to 0 for ZFS at this time. (From what
> I see ZFS file handles looking like.)
>
> Or, you could just rename fid_reserved to fid_pad and not worry about it.
>
> Maybe the ZFS folks could decide what they would prefer? rick
>
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
