1 /*******************************************************************************
2 * Filename: target_core_hba.c
4 * This file copntains the iSCSI HBA Transport related functions.
6 * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
7 * Copyright (c) 2005, 2006, 2007 SBE, Inc.
8 * Copyright (c) 2007-2010 Rising Tide Systems
9 * Copyright (c) 2008-2010 Linux-iSCSI.org
11 * Nicholas A. Bellinger <nab@kernel.org>
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 ******************************************************************************/
29 #include <linux/net.h>
30 #include <linux/string.h>
31 #include <linux/timer.h>
32 #include <linux/slab.h>
33 #include <linux/spinlock.h>
38 #include <target/target_core_base.h>
39 #include <target/target_core_device.h>
40 #include <target/target_core_device.h>
41 #include <target/target_core_tpg.h>
42 #include <target/target_core_transport.h>
44 #include "target_core_hba.h"
46 static LIST_HEAD(subsystem_list
);
47 static DEFINE_MUTEX(subsystem_mutex
);
49 int transport_subsystem_register(struct se_subsystem_api
*sub_api
)
51 struct se_subsystem_api
*s
;
53 INIT_LIST_HEAD(&sub_api
->sub_api_list
);
55 mutex_lock(&subsystem_mutex
);
56 list_for_each_entry(s
, &subsystem_list
, sub_api_list
) {
57 if (!(strcmp(s
->name
, sub_api
->name
))) {
58 printk(KERN_ERR
"%p is already registered with"
59 " duplicate name %s, unable to process"
60 " request\n", s
, s
->name
);
61 mutex_unlock(&subsystem_mutex
);
65 list_add_tail(&sub_api
->sub_api_list
, &subsystem_list
);
66 mutex_unlock(&subsystem_mutex
);
68 printk(KERN_INFO
"TCM: Registered subsystem plugin: %s struct module:"
69 " %p\n", sub_api
->name
, sub_api
->owner
);
72 EXPORT_SYMBOL(transport_subsystem_register
);
74 void transport_subsystem_release(struct se_subsystem_api
*sub_api
)
76 mutex_lock(&subsystem_mutex
);
77 list_del(&sub_api
->sub_api_list
);
78 mutex_unlock(&subsystem_mutex
);
80 EXPORT_SYMBOL(transport_subsystem_release
);
82 static struct se_subsystem_api
*core_get_backend(const char *sub_name
)
84 struct se_subsystem_api
*s
;
86 mutex_lock(&subsystem_mutex
);
87 list_for_each_entry(s
, &subsystem_list
, sub_api_list
) {
88 if (!strcmp(s
->name
, sub_name
))
91 mutex_unlock(&subsystem_mutex
);
94 if (s
->owner
&& !try_module_get(s
->owner
))
96 mutex_unlock(&subsystem_mutex
);
101 core_alloc_hba(const char *plugin_name
, u32 plugin_dep_id
, u32 hba_flags
)
106 hba
= kzalloc(sizeof(*hba
), GFP_KERNEL
);
108 printk(KERN_ERR
"Unable to allocate struct se_hba\n");
109 return ERR_PTR(-ENOMEM
);
112 INIT_LIST_HEAD(&hba
->hba_dev_list
);
113 spin_lock_init(&hba
->device_lock
);
114 spin_lock_init(&hba
->hba_queue_lock
);
115 mutex_init(&hba
->hba_access_mutex
);
117 hba
->hba_index
= scsi_get_new_index(SCSI_INST_INDEX
);
118 hba
->hba_flags
|= hba_flags
;
120 atomic_set(&hba
->max_queue_depth
, 0);
121 atomic_set(&hba
->left_queue_depth
, 0);
123 hba
->transport
= core_get_backend(plugin_name
);
124 if (!hba
->transport
) {
129 ret
= hba
->transport
->attach_hba(hba
, plugin_dep_id
);
133 spin_lock(&se_global
->hba_lock
);
134 hba
->hba_id
= se_global
->g_hba_id_counter
++;
135 list_add_tail(&hba
->hba_list
, &se_global
->g_hba_list
);
136 spin_unlock(&se_global
->hba_lock
);
138 printk(KERN_INFO
"CORE_HBA[%d] - Attached HBA to Generic Target"
139 " Core\n", hba
->hba_id
);
144 if (hba
->transport
->owner
)
145 module_put(hba
->transport
->owner
);
146 hba
->transport
= NULL
;
153 core_delete_hba(struct se_hba
*hba
)
155 struct se_device
*dev
, *dev_tmp
;
157 spin_lock(&hba
->device_lock
);
158 list_for_each_entry_safe(dev
, dev_tmp
, &hba
->hba_dev_list
, dev_list
) {
160 se_clear_dev_ports(dev
);
161 spin_unlock(&hba
->device_lock
);
163 se_release_device_for_hba(dev
);
165 spin_lock(&hba
->device_lock
);
167 spin_unlock(&hba
->device_lock
);
169 hba
->transport
->detach_hba(hba
);
171 spin_lock(&se_global
->hba_lock
);
172 list_del(&hba
->hba_list
);
173 spin_unlock(&se_global
->hba_lock
);
175 printk(KERN_INFO
"CORE_HBA[%d] - Detached HBA from Generic Target"
176 " Core\n", hba
->hba_id
);
178 if (hba
->transport
->owner
)
179 module_put(hba
->transport
->owner
);
181 hba
->transport
= NULL
;