On Mon, May 23, 2011 at 12:45 PM, Jeff Layton <jlayton@xxxxxxxxxx> wrote: > On Mon, 23 May 2011 11:58:50 -0500 > Steve French <smfrench@xxxxxxxxx> wrote: > >> On Mon, May 23, 2011 at 11:31 AM, Gerald Carter <jerry@xxxxxxxxxxxx> wrote: >> > On 05/23/2011 08:42 AM, Steve French wrote: >> > >> >> Shirish had done some experiments (and AFAIK has a small patch >> >> that fixed NFS export over CIFS which works, with the usual restrictions >> >> about having to return ESTALE if the NFS client tries to access >> >> an inode which has been flushed from the cache on the server side). >> >> >> >>>> For nfs v3 clients that can't handle ESTALE, we are probably >> >>>> stuck with having to wait for Samba to implement the flag >> >>> Flag? >> >> >> >> NTCreateX: FILE_OPEN_BY_FILE_ID >> >> >> >> IIRC Shirish verified that the Windows client will emit this flag, but their >> >> server had not gotten around to implementing it (although Samba could >> >> implement it now that their is an open-by-handle syscall). >> > >> > Hey Jeff/Steve, >> > >> > I found in [MS-CIFS] that says a server MUST return STATUS_NOT_SUPPORTED >> > for this option. >> Yes - Microsoft has said that their servers do return >> STATUS_NOT_SUPPORTED but this is not "MUST" in exactly the same sense >> as in an IETF RFC, and the discussion I had with JRA was about servers >> which support the Unix/POSIX extensions allowing this. >> > > Reality check -- this is only going to be useful iff: > > 1) such a thing were to materialize on the server side (and that will > probably be in samba only) > > ...and... > > 2) someone writes the code to take advantage of it > > ...and that still won't fix the aforementioned problem with > directories. Hang on - it is useful already. With Shirish's patch he was able to back up a Windows or Samba server via NFS. For running more complicated applications for long periods of time - it depends on the NFS client whether ESTALE is handled or not - but at least ESTALE is a documented return code and that the Linux NFS implementation did not yet merge Peter Staubach's fix for ESTALE is a bug in Linux NFS (some OS do handle ESTALE properly). -- Thanks, Steve -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
