linux/drivers/target/iscsi/iscsi_target_device.c
Roland Dreier 7dd03aca9d target: Fix max_cmd_sn increment w/o cmdsn mutex regressions
Current for-next iscsi target is broken:

commit 109e238174
Author: Roland Dreier <roland@purestorage.com>
Date:   Thu Jul 23 14:53:32 2015 -0700

    target: Drop iSCSI use of mutex around max_cmd_sn increment

This patch fixes incorrect pr_debug() + atomic_inc_return() usage
within iscsit_increment_maxcmdsn() code.

Also fix funny iscsit_determine_maxcmdsn() usage and update
iscsi_target_do_tx_login_io() code.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-09-11 00:32:28 -07:00

66 lines
2.1 KiB
C

/*******************************************************************************
* This file contains the iSCSI Virtual Device and Disk Transport
* agnostic related functions.
*
* (c) Copyright 2007-2013 Datera, Inc.
*
* Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
******************************************************************************/
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/iscsi/iscsi_target_core.h>
#include "iscsi_target_device.h"
#include "iscsi_target_tpg.h"
#include "iscsi_target_util.h"
void iscsit_determine_maxcmdsn(struct iscsi_session *sess)
{
struct se_node_acl *se_nacl;
/*
* This is a discovery session, the single queue slot was already
* assigned in iscsi_login_zero_tsih(). Since only Logout and
* Text Opcodes are allowed during discovery we do not have to worry
* about the HBA's queue depth here.
*/
if (sess->sess_ops->SessionType)
return;
se_nacl = sess->se_sess->se_node_acl;
/*
* This is a normal session, set the Session's CmdSN window to the
* struct se_node_acl->queue_depth. The value in struct se_node_acl->queue_depth
* has already been validated as a legal value in
* core_set_queue_depth_for_node().
*/
sess->cmdsn_window = se_nacl->queue_depth;
atomic_add(se_nacl->queue_depth - 1, &sess->max_cmd_sn);
}
void iscsit_increment_maxcmdsn(struct iscsi_cmd *cmd, struct iscsi_session *sess)
{
u32 max_cmd_sn;
if (cmd->immediate_cmd || cmd->maxcmdsn_inc)
return;
cmd->maxcmdsn_inc = 1;
max_cmd_sn = atomic_inc_return(&sess->max_cmd_sn);
pr_debug("Updated MaxCmdSN to 0x%08x\n", max_cmd_sn);
}
EXPORT_SYMBOL(iscsit_increment_maxcmdsn);