On Tue, Nov 10, 2020 at 04:07:41PM -0500, Olga Kornievskaia wrote: > On Tue, Nov 10, 2020 at 3:14 PM J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote: > > > > On Mon, Nov 09, 2020 at 10:46:12PM -0800, Dai Ngo wrote: > > > > > > On 11/9/20 2:26 PM, Dai Ngo wrote: > > > > > > > >On 11/9/20 12:42 PM, J. Bruce Fields wrote: > > > >>On Mon, Nov 09, 2020 at 11:34:08AM -0800, Dai Ngo wrote: > > > >>>On 11/9/20 10:30 AM, J. Bruce Fields wrote: > > > >>>>On Tue, Oct 20, 2020 at 11:34:35AM -0700, Dai Ngo wrote: > > > >>>>>On 10/20/20 10:01 AM, J. Bruce Fields wrote: > > > >>>>>>On Sun, Oct 18, 2020 at 11:42:49PM -0400, Dai Ngo wrote: > > > >>>>>>>NFS_FS=y as dependency of CONFIG_NFSD_V4_2_INTER_SSC still have > > > >>>>>>>build errors and some configs with NFSD=m to get NFS4ERR_STALE > > > >>>>>>>error when doing inter server copy. > > > >>>>>>> > > > >>>>>>>Added ops table in nfs_common for knfsd to access NFS > > > >>>>>>>client modules. > > > >>>>>>OK, looks reasonable to me, applying. Does this resolve all the > > > >>>>>>problems you've seen, or is there any bad case left? > > > >>>>>Thanks Bruce. > > > >>>>> > > > >>>>>With this patch, I no longer see the NFS4ERR_STALE in any config. > > > >>>>> > > > >>>>>The problem with NFS4ERR_STALE was because of a bug in > > > >>>>>nfs42_ssc_open. > > > >>>>>When CONFIG_NFSD_V4_2_INTER_SSC is not defined, nfs42_ssc_open > > > >>>>>returns NULL which is incorrect allowing the operation to continue > > > >>>>>until nfsd4_putfh which does not have the code to handle > > > >>>>>nfserr_stale. > > > >>>>> > > > >>>>>With this patch, when CONFIG_NFSD_V4_2_INTER_SSC is not defined the > > > >>>>>new nfs42_ssc_open returns ERR_PTR(-EIO) which causes the NFS client > > > >>>>>to switch over to the split copying (read src and write to dst). > > > >>>>That sounds reasonable, but I don't see any of the patches you've sent > > > >>>>changing that error return. Did I overlook something, or did you mean > > > >>>>to append a patch to this message? > > > >>>Since with the patch, I did not run into the condition where > > > >>>NFS4ERR_STALE > > > >>>is returned so I did not fix this return error code. Do you want me to > > > >>>submit another patch to change the returned error code from > > > >>>NFS4ERR_STALE > > > >>>to NFS4ERR_NOTSUPP if it ever runs into that condition? > > > >>That would be great, thanks. (I mean, it is still possible to hit that > > > >>case, right? You just didn't test with !CONFIG_NFSD_V4_2_INTER_SSC ?) > > > > > > > >will do. I did tested with (!CONFIG_NFSD_V4_2_INTER_SSC) but did not hit > > > >this case. > > > > > > I need to qualify this, the copy_file_range syscall did not return > > > ESTALE in the test. > > > > > > >Because with this patch, when CONFIG_NFSD_V4_2_INTER_SSC is not > > > >defined the new nfs42_ssc_open returns ERR_PTR(-EIO), instead of NULL in > > > >the old code, which causes the NFS client to switch over to the split > > > >copying (read src and write to dst). > > > > > > This is not the reason why the client switches to generic_copy_file_range. > > > > > > >Returning NULL in the old nfs42_ssc_open is not correct, it allows > > > >the copy > > > >operation to proceed and hits the NFS4ERR_STALE case in the COPY > > > >operation. > > > > > > I retested with (!CONFIG_NFSD_V4_2_INTER_SSC) and saw NFS4ERR_STALE > > > returned for the PUTFH of the SRC in the COPY compound. However on the > > > client nfs42_proc_copy (with commit 7e350197a1c10) replaced the ESTALE > > > with EOPNOTSUPP causing nfs4_copy_file_range to use generic_copy_file_range > > > to do the copy. > > > > > > The ESTALE error is only returned by copy_file_range if the client > > > does not have commit 7e350197a1c10. So I think there is no need to > > > make any change on the source server for the NFS4ERR_STALE error. > > > > I don't believe NFS4ERR_STALE is the correct error for the server to > > return. It's nice that the client is able to do the right thing despite > > the server returning the wrong error, but we should still try to get > > this right on the server. > > Hi Bruce, > > ERR_STALE is the appropriate error to be returned by the server that > gets a COPY compound when it doesn't support COPY. Since server can't > understand the filehandle so it can't process it so we can't get to > processing COPY opcode where the server could have returned > EOPNOTSUPP. The case we're discussing is the case where we support COPY but not server-to-server copy. --b. > Thus a client side patch is needed and the server is doing > everything it can in the situation. > > I'm confused about the title of this patch. I thought what it does is > removes NFSD dependency on the NFS and instead loads the needed > function dynamically. > > Honestly, I don't understand why that allows removal of the NFS_FS > from the dependencies I don't understand. nfs4_ssc_open calls nfs > client functions that are built when NFS_FS is compiled but I'm > assuming will not be otherwise.
