From: NeilBrown <neilb@cse.unsw.edu.au>

Return the special NFSv4 pseudo filesystem fsid (0/0) in a GETATTR on an
NFSv4 pseudo filesystem node.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/fs/nfsd/nfs4xdr.c |   15 ++++++++++-----
 1 files changed, 10 insertions(+), 5 deletions(-)

diff -puN fs/nfsd/nfs4xdr.c~knfsd-nfsd4-use-the-fsid-export-option-when-returning-the-fsid-attribute fs/nfsd/nfs4xdr.c
--- 25/fs/nfsd/nfs4xdr.c~knfsd-nfsd4-use-the-fsid-export-option-when-returning-the-fsid-attribute	2004-11-15 22:07:06.743563824 -0800
+++ 25-akpm/fs/nfsd/nfs4xdr.c	2004-11-15 22:07:06.748563064 -0800
@@ -1425,7 +1425,7 @@ nfsd4_encode_fattr(struct svc_fh *fhp, s
 		if (status)
 			goto out_nfserr;
 	}
-	if ((bmval0 & FATTR4_WORD0_FILEHANDLE) && !fhp) {
+	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
 		fh_init(&tempfh, NFS4_FHSIZE);
 		status = fh_compose(&tempfh, exp, dentry, NULL);
 		if (status)
@@ -1508,10 +1508,15 @@ nfsd4_encode_fattr(struct svc_fh *fhp, s
 	if (bmval0 & FATTR4_WORD0_FSID) {
 		if ((buflen -= 16) < 0)
 			goto out_resource;
-		WRITE32(0);
-		WRITE32(MAJOR(stat.dev));
-		WRITE32(0);
-		WRITE32(MINOR(stat.dev));
+		if (is_fsid(fhp, rqstp->rq_reffh)) {
+			WRITE64((u64)exp->ex_fsid);
+			WRITE64((u64)0);
+		} else {
+			WRITE32(0);
+			WRITE32(MAJOR(stat.dev));
+			WRITE32(0);
+			WRITE32(MINOR(stat.dev));
+		}
 	}
 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
 		if ((buflen -= 4) < 0)
_