[PATCH] nfsd4: fix fh_expire_type

We're returning NFS4_FH_NOEXPIRE_WITH_OPEN | NFS4_FH_VOL_RENAME for the
fh_expire_type attribute. This is incorrect:
1. The spec actually only allows NOEXPIRE_WITH_OPEN when
VOLATILE_ANY is also set.
2. Filehandles for open files can expire, if the file is removed
and there is a reboot.
3. Filehandles are only volatile on rename in the nosubtree check
case.

Unfortunately, there's no way to indicate that we only expire on remove. So
our only choice is FH4_VOLATILE_ANY. Although it's redundant, we also set
FH4_VOL_RENAME in the subtree check case, since subtreecheck does actually
cause problems in practice and it seems possibly useful to give clients some
way to distinguish that case.

Fix a mispelled #define while we're at it.

Signed-off-by: J. Bruce Fields <[e-mail]>
Signed-off-by: Neil Brown <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/nfsd/nfs4xdr.c

···
 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
 		if ((buflen -= 4) < 0)
 			goto out_resource;
-		WRITE32( NFS4_FH_NOEXPIRE_WITH_OPEN | NFS4_FH_VOL_RENAME );
+		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
+			WRITE32(NFS4_FH_VOLATILE_ANY);
+		else
+			WRITE32(NFS4_FH_VOLATILE_ANY|NFS4_FH_VOL_RENAME);
 	}
 	if (bmval0 & FATTR4_WORD0_CHANGE) {
 		/*

include/linux/nfs4.h

···
 #define NFS4_ACCESS_DELETE      0x0010
 #define NFS4_ACCESS_EXECUTE     0x0020
 
-#define NFS4_FH_PERISTENT		0x0000
+#define NFS4_FH_PERSISTENT		0x0000
 #define NFS4_FH_NOEXPIRE_WITH_OPEN	0x0001
 #define NFS4_FH_VOLATILE_ANY		0x0002
 #define NFS4_FH_VOL_MIGRATION		0x0004