[PATCH 01/10] smb: smbdirect: introduce smbdirect_mr_io.{kref, mutex} and SMBDIRECT_MR_DISABLED

[Stefan Metzmacher]

This will be used in the next commits in order to improve the
client code.

A broken connection can just disable the smbdirect_mr_io while
keeping the memory arround for the caller.

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>
---
 fs/smb/common/smbdirect/smbdirect_socket.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/fs/smb/common/smbdirect/smbdirect_socket.h b/fs/smb/common/smbdirect/smbdirect_socket.h
index db22a1d0546b..361db7f9f623 100644
--- a/fs/smb/common/smbdirect/smbdirect_socket.h
+++ b/fs/smb/common/smbdirect/smbdirect_socket.h
@@ -437,13 +437,22 @@ enum smbdirect_mr_state {
 	SMBDIRECT_MR_READY,
 	SMBDIRECT_MR_REGISTERED,
 	SMBDIRECT_MR_INVALIDATED,
-	SMBDIRECT_MR_ERROR
+	SMBDIRECT_MR_ERROR,
+	SMBDIRECT_MR_DISABLED
 };
 
 struct smbdirect_mr_io {
 	struct smbdirect_socket *socket;
 	struct ib_cqe cqe;
 
+	/*
+	 * We can have up to two references:
+	 * 1. by the connection
+	 * 2. by the registration
+	 */
+	struct kref kref;
+	struct mutex mutex;
+
 	struct list_head list;
 
 	enum smbdirect_mr_state state;
-- 
2.43.0