nfsd41: make sure nfs server process OPEN with EXCLUSIVE4_1 correctly

The NFS server uses nfsd_create_v3 to handle EXCLUSIVE4_1 opens, but
that function is not prepared to handle them.

Rename nfsd_create_v3() to do_nfsd_create(), and add handling of
EXCLUSIVE4_1.

Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 4d2509f..e0bbac0 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -58,7 +58,7 @@
 				int type, dev_t rdev, struct svc_fh *res);
 #ifdef CONFIG_NFSD_V3
 __be32		nfsd_access(struct svc_rqst *, struct svc_fh *, u32 *, u32 *);
-__be32		nfsd_create_v3(struct svc_rqst *, struct svc_fh *,
+__be32		do_nfsd_create(struct svc_rqst *, struct svc_fh *,
 				char *name, int len, struct iattr *attrs,
 				struct svc_fh *res, int createmode,
 				u32 *verifier, int *truncp, int *created);