nfsd: Add ALLOCATE support

The ALLOCATE operation is used to preallocate space in a file.  I can do
this by using vfs_fallocate() to do the actual preallocation.

ALLOCATE only returns a status indicator, so we don't need to write a
special encode() function.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index c2ff3f1..7ffdb14 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -54,6 +54,8 @@
 #ifdef CONFIG_NFSD_V4
 __be32          nfsd4_set_nfs4_label(struct svc_rqst *, struct svc_fh *,
 		    struct xdr_netobj *);
+__be32		nfsd4_vfs_fallocate(struct svc_rqst *, struct svc_fh *,
+				    struct file *, loff_t, loff_t, int);
 #endif /* CONFIG_NFSD_V4 */
 __be32		nfsd_create(struct svc_rqst *, struct svc_fh *,
 				char *name, int len, struct iattr *attrs,