NFSD: add support for sending CB_RECALL_ANY

Add XDR encode and decode function for CB_RECALL_ANY.

Signed-off-by: Dai Ngo <[e-mail]>
Signed-off-by: Chuck Lever <[e-mail]>

fs/nfsd/nfs4callback.c

···
  * 1 Protocol"
  */
 
+static void encode_uint32(struct xdr_stream *xdr, u32 n)
+{
+	WARN_ON_ONCE(xdr_stream_encode_u32(xdr, n) < 0);
+}
+
+static void encode_bitmap4(struct xdr_stream *xdr, const __u32 *bitmap,
+			   size_t len)
+{
+	WARN_ON_ONCE(xdr_stream_encode_uint32_array(xdr, bitmap, len) < 0);
+}
+
 /*
  *	nfs_cb_opnum4
  *
···
 }
 
 /*
+ * CB_RECALLANY4args
+ *
+ *	struct CB_RECALLANY4args {
+ *		uint32_t	craa_objects_to_keep;
+ *		bitmap4		craa_type_mask;
+ *	};
+ */
+static void
+encode_cb_recallany4args(struct xdr_stream *xdr,
+	struct nfs4_cb_compound_hdr *hdr, struct nfsd4_cb_recall_any *ra)
+{
+	encode_nfs_cb_opnum4(xdr, OP_CB_RECALL_ANY);
+	encode_uint32(xdr, ra->ra_keep);
+	encode_bitmap4(xdr, ra->ra_bmval, ARRAY_SIZE(ra->ra_bmval));
+	hdr->nops++;
+}
+
+/*
  * CB_SEQUENCE4args
  *
  *	struct CB_SEQUENCE4args {
···
 	encode_cb_nops(&hdr);
 }
 
+/*
+ * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects
+ */
+static void
+nfs4_xdr_enc_cb_recall_any(struct rpc_rqst *req,
+		struct xdr_stream *xdr, const void *data)
+{
+	const struct nfsd4_callback *cb = data;
+	struct nfsd4_cb_recall_any *ra;
+	struct nfs4_cb_compound_hdr hdr = {
+		.ident = cb->cb_clp->cl_cb_ident,
+		.minorversion = cb->cb_clp->cl_minorversion,
+	};
+
+	ra = container_of(cb, struct nfsd4_cb_recall_any, ra_cb);
+	encode_cb_compound4args(xdr, &hdr);
+	encode_cb_sequence4args(xdr, cb, &hdr);
+	encode_cb_recallany4args(xdr, &hdr, ra);
+	encode_cb_nops(&hdr);
+}
 
 /*
  * NFSv4.0 and NFSv4.1 XDR decode functions
···
 		return status;
 
 	return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status);
+}
+
+/*
+ * 20.6. Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects
+ */
+static int
+nfs4_xdr_dec_cb_recall_any(struct rpc_rqst *rqstp,
+				  struct xdr_stream *xdr,
+				  void *data)
+{
+	struct nfsd4_callback *cb = data;
+	struct nfs4_cb_compound_hdr hdr;
+	int status;
+
+	status = decode_cb_compound4res(xdr, &hdr);
+	if (unlikely(status))
+		return status;
+	status = decode_cb_sequence4res(xdr, cb);
+	if (unlikely(status || cb->cb_seq_status))
+		return status;
+	status =  decode_cb_op_status(xdr, OP_CB_RECALL_ANY, &cb->cb_status);
+	return status;
 }
 
 #ifdef CONFIG_NFSD_PNFS
···
 #endif
 	PROC(CB_NOTIFY_LOCK,	COMPOUND,	cb_notify_lock,	cb_notify_lock),
 	PROC(CB_OFFLOAD,	COMPOUND,	cb_offload,	cb_offload),
+	PROC(CB_RECALL_ANY,	COMPOUND,	cb_recall_any,	cb_recall_any),
 };
 
 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)];

fs/nfsd/state.h

···
 	NFSPROC4_CLNT_CB_OFFLOAD,
 	NFSPROC4_CLNT_CB_SEQUENCE,
 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
+	NFSPROC4_CLNT_CB_RECALL_ANY,
 };
 
 /* Returns true iff a is later than b: */

fs/nfsd/xdr4.h

···
 			union nfsd4_op_u *);
 };
 
+struct nfsd4_cb_recall_any {
+	struct nfsd4_callback	ra_cb;
+	u32			ra_keep;
+	u32			ra_bmval[1];
+};
 
 #endif

fs/nfsd/xdr4cb.h

···
 #define NFS4_dec_cb_offload_sz		(cb_compound_dec_hdr_sz  +      \
 					cb_sequence_dec_sz +            \
 					op_dec_sz)
+#define NFS4_enc_cb_recall_any_sz	(cb_compound_enc_hdr_sz +       \
+					cb_sequence_enc_sz +            \
+					1 + 1 + 1)
+#define NFS4_dec_cb_recall_any_sz	(cb_compound_dec_hdr_sz  +      \
+					cb_sequence_dec_sz +            \
+					op_dec_sz)