nfsd: drop the ncf_cb_bmap field

This is always the same value, and in a later patch we're going to need
to set bits in WORD2. We can simplify this code and save a little space
in the delegation too. Just hardcode the bitmap in the callback encode
function.

Signed-off-by: Jeff Layton <[e-mail]>
Signed-off-by: Chuck Lever <[e-mail]>

fs/nfsd/nfs4callback.c

···
 	struct nfs4_delegation *dp =
 		container_of(fattr, struct nfs4_delegation, dl_cb_fattr);
 	struct knfsd_fh *fh = &dp->dl_stid.sc_file->fi_fhandle;
+	u32 bmap[1];
+
+	bmap[0] = FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE;
 
 	encode_nfs_cb_opnum4(xdr, OP_CB_GETATTR);
 	encode_nfs_fh4(xdr, fh);
-	encode_bitmap4(xdr, fattr->ncf_cb_bmap, ARRAY_SIZE(fattr->ncf_cb_bmap));
+	encode_bitmap4(xdr, bmap, ARRAY_SIZE(bmap));
 	hdr->nops++;
 }
 

fs/nfsd/nfs4state.c

···
 	nfsd4_init_cb(&dp->dl_cb_fattr.ncf_getattr, dp->dl_stid.sc_client,
 			&nfsd4_cb_getattr_ops, NFSPROC4_CLNT_CB_GETATTR);
 	dp->dl_cb_fattr.ncf_file_modified = false;
-	dp->dl_cb_fattr.ncf_cb_bmap[0] = FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE;
 	get_nfs4_file(fp);
 	dp->dl_stid.sc_file = fp;
 	return dp;

fs/nfsd/state.h

···
 struct nfs4_cb_fattr {
 	struct nfsd4_callback ncf_getattr;
 	u32 ncf_cb_status;
-	u32 ncf_cb_bmap[1];
 
 	/* from CB_GETATTR reply */
 	u64 ncf_cb_change;