Re: [PATCH/RFC] Lustre VFS patch

[Trond Myklebust <trond.myklebust@fys.uio.no>]

På må , 24/05/2004 klokka 08:05, skreiv hch@infradead.org:
> I can't comment on the exact change, you need to talk to trond about
> these.  But as-is they change the API exported to filesystems and thus
> it's and absolute no-go for 2.6.   Where have you been when Trond's
> intent patches went in?  Hiding under a rock?

To be fair: At the time, Peter and I did indeed discuss the changes that
were needed in order to support both Lustre and NFS. The main reason why
I ended up sending in the "NFS minimal" patch was IIRC that Peter was
not ready at the time to send in a full Lustre client that could make
use of this interface.

Peter, I have a couple of objections here

        vfs_intent-flags_rename-vanilla-2.6.patch and
        vfs-intent_exec-vanilla-2.6.patch breaks NFS (though ironically
        it fixes CIFS) due to that gratuitous change of semantics from
        FMODE_READ/FMODE_WRITE to O_RDONLY/O_WRONLY/O_RDWR. Exactly why
        couldn't Lustre work with the native VFS semantics?
        
        vfs_intent-flags_rename-vanilla-2.6.patch also reverts the
        format from being a union of intents for various operations to
        being a single structure. This goes against what was agreed upon
        on linux-fsdevel when this issue was discussed last summer (in
        fact Linus was the one who requested the union approach). What
        justification exists now for a change?

        The vfs-intent_lustre-vanilla-2.6.patch + the "intent_release()"
        code. What if you end up crossing a mountpoint? How do you then
        know to which superblock/filesystem the private field belongs if
        there are more than one user of this mechanism?

        vfs-revalidate_counter-vanilla-2.6.patch: can't "counter" be put
        into the private part of your intent structure so that the whole
        test may be done within Lustre?

        vfs-revalidate_special-vanilla-2.6.patch: see the use of the
        flag FS_REVAL_DOT in order to enable the revalidation of the
        current directory for those filesystems that need to do so.

Cheers,
  Trond