[PATCH v2 039/127] smb: smbdirect: introduce smbdirect_connection_grant_recv_credits()

[Stefan Metzmacher]

This is a copy of manage_credits_prior_sending() in the server.

It is very similar to manage_credits_prior_sending() in the
client, the only difference is that
atomic_add(new_credits, &sc->recv_io.credits.count) is done
in the caller there.

It will replace both versions in future.

Cc: Steve French <smfrench at gmail.com>
Cc: Tom Talpey <tom at talpey.com>
Cc: Long Li <longli at microsoft.com>
Cc: Namjae Jeon <linkinjeon at kernel.org>
Cc: linux-cifs at vger.kernel.org
Cc: samba-technical at lists.samba.org
Signed-off-by: Stefan Metzmacher <metze at samba.org>
---
 .../common/smbdirect/smbdirect_connection.c   | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/fs/smb/common/smbdirect/smbdirect_connection.c b/fs/smb/common/smbdirect/smbdirect_connection.c
index 36f82b090bc7..da2e9ecdd98d 100644
--- a/fs/smb/common/smbdirect/smbdirect_connection.c
+++ b/fs/smb/common/smbdirect/smbdirect_connection.c
@@ -1037,6 +1037,26 @@ static int smbdirect_connection_wait_for_credits(struct smbdirect_socket *sc,
 	} while (true);
 }
 
+__maybe_unused /* this is temporary while this file is included in orders */
+static u16 smbdirect_connection_grant_recv_credits(struct smbdirect_socket *sc)
+{
+	u16 new_credits;
+
+	if (atomic_read(&sc->recv_io.credits.count) >= sc->recv_io.credits.target)
+		return 0;
+
+	new_credits = atomic_read(&sc->recv_io.posted.count);
+	if (new_credits == 0)
+		return 0;
+
+	new_credits -= atomic_read(&sc->recv_io.credits.count);
+	if (new_credits <= 0)
+		return 0;
+
+	atomic_add(new_credits, &sc->recv_io.credits.count);
+	return new_credits;
+}
+
 __maybe_unused /* this is temporary while this file is included in orders */
 static void smbdirect_connection_send_io_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-- 
2.43.0