On Tue, 2025-01-21 at 11:39 +0100, Amir Goldstein wrote:
> Commit 466e16f0920f3 ("nfsd: check for EBUSY from vfs_rmdir/vfs_unink.")
> mapped EBUSY host error from rmdir/unlink operation to avoid unknown
> error server warning.
>
> The same reason that casued the reported EBUSY on rmdir() (dir is a
> local mount point in some other bind mount) could also cause EBUSY on
> rename and some filesystems (e.g. FUSE) can return EBUSY on other
> operations like open().
>
> Therefore, to avoid unknown error warning in server, we need to map
> EBUSY for all operations.
>
> The original fix mapped EBUSY to NFS4ERR_FILE_OPEN in v4 server and
> to NFS4ERR_ACCESS in v2/v3 server.
>
> During the discussion on this issue, Trond claimed that the mapping
> made from EBUSY to NFS4ERR_FILE_OPEN was incorrect according to the
> protocol spec and specifically, NFS4ERR_FILE_OPEN is not expected
> for directories.
>
> To keep things simple and consistent and avoid the server warning,
> map EBUSY to NFS4ERR_ACCESS for all operations in all protocol versions.
>
> Note that the mapping of NFS4ERR_FILE_OPEN to NFSERR_ACCESS in
> nfsd3_map_status() and nfsd_map_status() remains for possible future
> return of NFS4ERR_FILE_OPEN in a more specific use case (e.g. an unlink
> of a sillyrenamed non-dir).
>
> Fixes: 466e16f0920f3 ("nfsd: check for EBUSY from vfs_rmdir/vfs_unink.")
> Link: https://lore.kernel.org/linux-nfs/20250120172016.397916-1-amir73il@xxxxxxxxx/
> Cc: Trond Myklebust <trondmy@xxxxxxxxxxxxxxx>
> Cc: NeilBrown <neilb@xxxxxxx>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> fs/nfsd/vfs.c | 10 ++--------
> 1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 29cb7b812d713..290c7db8a6180 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -69,6 +69,7 @@ nfserrno (int errno)
> { nfserr_fbig, -E2BIG },
> { nfserr_stale, -EBADF },
> { nfserr_acces, -EACCES },
> + { nfserr_acces, -EBUSY},
> { nfserr_exist, -EEXIST },
> { nfserr_xdev, -EXDEV },
> { nfserr_mlink, -EMLINK },
> @@ -2006,14 +2007,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
> out_drop_write:
> fh_drop_write(fhp);
> out_nfserr:
> - if (host_err == -EBUSY) {
> - /* name is mounted-on. There is no perfect
> - * error status.
> - */
> - err = nfserr_file_open;
> - } else {
> - err = nfserrno(host_err);
> - }
> + err = nfserrno(host_err);
> out:
> return err;
> out_unlock:
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
