cifs: New optype for session operations.

We used to share the CIFS_NEG_OP flag between negotiate and
session authentication. There was an assumption in the code that
CIFS_NEG_OP is used by negotiate only. So introcuded CIFS_SESS_OP
and used it for session setup optypes.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/cifsglob.h

@@ -1704,7 +1704,9 @@ static inline bool is_retryable_error(int error)
 #define   CIFS_ECHO_OP      0x080    /* echo request */
 #define   CIFS_OBREAK_OP   0x0100    /* oplock break request */
 #define   CIFS_NEG_OP      0x0200    /* negotiate request */
-#define   CIFS_OP_MASK     0x0380    /* mask request type */
+/* Lower bitmask values are reserved by others below. */
+#define   CIFS_SESS_OP     0x2000    /* session setup request */
+#define   CIFS_OP_MASK     0x2380    /* mask request type */
 
 #define   CIFS_HAS_CREDITS 0x0400    /* already has credits */
 #define   CIFS_TRANSFORM_REQ 0x0800    /* transform request before sending */

fs/cifs/smb2ops.c

@@ -84,7 +84,9 @@ smb2_add_credits(struct TCP_Server_Info *server,
 		pr_warn_once("server overflowed SMB3 credits\n");
 	}
 	server->in_flight--;
-	if (server->in_flight == 0 && (optype & CIFS_OP_MASK) != CIFS_NEG_OP)
+	if (server->in_flight == 0 &&
+	   ((optype & CIFS_OP_MASK) != CIFS_NEG_OP) &&
+	   ((optype & CIFS_OP_MASK) != CIFS_SESS_OP))
 		rc = change_conf(server);
 	/*
 	 * Sometimes server returns 0 credits on oplock break ack - we need to

fs/cifs/smb2pdu.c

@@ -1261,7 +1261,7 @@ SMB2_sess_sendreceive(struct SMB2_sess_data *sess_data)
 			    cifs_ses_server(sess_data->ses),
 			    &rqst,
 			    &sess_data->buf0_type,
-			    CIFS_LOG_ERROR | CIFS_NEG_OP, &rsp_iov);
+			    CIFS_LOG_ERROR | CIFS_SESS_OP, &rsp_iov);
 	cifs_small_buf_release(sess_data->iov[0].iov_base);
 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
 

fs/cifs/transport.c

@@ -1171,7 +1171,7 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	/*
 	 * Compounding is never used during session establish.
 	 */
-	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
+	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP) || (optype & CIFS_SESS_OP))
 		smb311_update_preauth_hash(ses, rqst[0].rq_iov,
 					   rqst[0].rq_nvec);
 
@@ -1236,7 +1236,7 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	/*
 	 * Compounding is never used during session establish.
 	 */
-	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
+	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP) || (optype & CIFS_SESS_OP)) {
 		struct kvec iov = {
 			.iov_base = resp_iov[0].iov_base,
 			.iov_len = resp_iov[0].iov_len