smb: smbdirect: introduce smbdirect_socket.recv_io.{posted,credits}

This will be used by client and server soon in order to maintain
the state of posted recv_io messages and granted credits.

Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

Author: metze-samba

fs/smb/common/smbdirect/smbdirect_socket.h

@@ -135,6 +135,23 @@ struct smbdirect_socket {
 			spinlock_t lock;
 		} free;
 
+		/*
+		 * The state for posted recv_io messages
+		 * and the refill work struct.
+		 */
+		struct {
+			atomic_t count;
+			struct work_struct refill_work;
+		} posted;
+
+		/*
+		 * The credit state for the recv side
+		 */
+		struct {
+			u16 target;
+			atomic_t count;
+		} credits;
+
 		/*
 		 * The list of arrived non-empty smbdirect_recv_io
 		 * structures
@@ -204,6 +221,10 @@ static __always_inline void smbdirect_socket_init(struct smbdirect_socket *sc)
 	INIT_LIST_HEAD(&sc->recv_io.free.list);
 	spin_lock_init(&sc->recv_io.free.lock);
 
+	atomic_set(&sc->recv_io.posted.count, 0);
+
+	atomic_set(&sc->recv_io.credits.count, 0);
+
 	INIT_LIST_HEAD(&sc->recv_io.reassembly.list);
 	spin_lock_init(&sc->recv_io.reassembly.lock);
 	init_waitqueue_head(&sc->recv_io.reassembly.wait_queue);