xref: /linux/drivers/target/iscsi/iscsi_target_device.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains the iSCSI Virtual Device and Disk Transport
4  * agnostic related functions.
5  *
6  * (c) Copyright 2007-2013 Datera, Inc.
7  *
8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
9  *
10  ******************************************************************************/
11 
12 #include <target/target_core_base.h>
13 #include <target/target_core_fabric.h>
14 
15 #include <target/iscsi/iscsi_target_core.h>
16 #include "iscsi_target_device.h"
17 #include "iscsi_target_tpg.h"
18 #include "iscsi_target_util.h"
19 
20 void iscsit_determine_maxcmdsn(struct iscsit_session *sess)
21 {
22 	struct se_node_acl *se_nacl;
23 
24 	/*
25 	 * This is a discovery session, the single queue slot was already
26 	 * assigned in iscsi_login_zero_tsih().  Since only Logout and
27 	 * Text Opcodes are allowed during discovery we do not have to worry
28 	 * about the HBA's queue depth here.
29 	 */
30 	if (sess->sess_ops->SessionType)
31 		return;
32 
33 	se_nacl = sess->se_sess->se_node_acl;
34 
35 	/*
36 	 * This is a normal session, set the Session's CmdSN window to the
37 	 * struct se_node_acl->queue_depth.  The value in struct se_node_acl->queue_depth
38 	 * has already been validated as a legal value in
39 	 * core_set_queue_depth_for_node().
40 	 */
41 	sess->cmdsn_window = se_nacl->queue_depth;
42 	atomic_add(se_nacl->queue_depth - 1, &sess->max_cmd_sn);
43 }
44 
45 void iscsit_increment_maxcmdsn(struct iscsit_cmd *cmd, struct iscsit_session *sess)
46 {
47 	u32 max_cmd_sn;
48 
49 	if (cmd->immediate_cmd || cmd->maxcmdsn_inc)
50 		return;
51 
52 	cmd->maxcmdsn_inc = 1;
53 
54 	max_cmd_sn = atomic_inc_return(&sess->max_cmd_sn);
55 	pr_debug("Updated MaxCmdSN to 0x%08x\n", max_cmd_sn);
56 }
57 EXPORT_SYMBOL(iscsit_increment_maxcmdsn);
58