1 /*******************************************************************************
2  * This file contains the iSCSI Virtual Device and Disk Transport
3  * agnostic related functions.
4  *
5  * (c) Copyright 2007-2013 Datera, Inc.
6  *
7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  ******************************************************************************/
19 
20 #include <scsi/scsi_device.h>
21 #include <target/target_core_base.h>
22 #include <target/target_core_fabric.h>
23 
24 #include "iscsi_target_core.h"
25 #include "iscsi_target_device.h"
26 #include "iscsi_target_tpg.h"
27 #include "iscsi_target_util.h"
28 
29 void iscsit_determine_maxcmdsn(struct iscsi_session *sess)
30 {
31 	struct se_node_acl *se_nacl;
32 
33 	/*
34 	 * This is a discovery session, the single queue slot was already
35 	 * assigned in iscsi_login_zero_tsih().  Since only Logout and
36 	 * Text Opcodes are allowed during discovery we do not have to worry
37 	 * about the HBA's queue depth here.
38 	 */
39 	if (sess->sess_ops->SessionType)
40 		return;
41 
42 	se_nacl = sess->se_sess->se_node_acl;
43 
44 	/*
45 	 * This is a normal session, set the Session's CmdSN window to the
46 	 * struct se_node_acl->queue_depth.  The value in struct se_node_acl->queue_depth
47 	 * has already been validated as a legal value in
48 	 * core_set_queue_depth_for_node().
49 	 */
50 	sess->cmdsn_window = se_nacl->queue_depth;
51 	sess->max_cmd_sn = (sess->max_cmd_sn + se_nacl->queue_depth) - 1;
52 }
53 
54 void iscsit_increment_maxcmdsn(struct iscsi_cmd *cmd, struct iscsi_session *sess)
55 {
56 	if (cmd->immediate_cmd || cmd->maxcmdsn_inc)
57 		return;
58 
59 	cmd->maxcmdsn_inc = 1;
60 
61 	mutex_lock(&sess->cmdsn_mutex);
62 	sess->max_cmd_sn += 1;
63 	pr_debug("Updated MaxCmdSN to 0x%08x\n", sess->max_cmd_sn);
64 	mutex_unlock(&sess->cmdsn_mutex);
65 }
66 EXPORT_SYMBOL(iscsit_increment_maxcmdsn);
67