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1/*******************************************************************************
2 * Filename: target_core_hba.c
3 *
4 * This file contains the TCM HBA Transport related functions.
5 *
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
10 *
11 * Nicholas A. Bellinger <nab@kernel.org>
12 *
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.
17 *
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.
22 *
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.
26 *
27 ******************************************************************************/
28
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>
34#include <linux/in.h>
35#include <net/sock.h>
36#include <net/tcp.h>
37
38#include <target/target_core_base.h>
39#include <target/target_core_device.h>
40#include <target/target_core_tpg.h>
41#include <target/target_core_transport.h>
42
43#include "target_core_hba.h"
44
45static LIST_HEAD(subsystem_list);
46static DEFINE_MUTEX(subsystem_mutex);
47
48static u32 hba_id_counter;
49
50static DEFINE_SPINLOCK(hba_lock);
51static LIST_HEAD(hba_list);
52
53int transport_subsystem_register(struct se_subsystem_api *sub_api)
54{
55 struct se_subsystem_api *s;
56
57 INIT_LIST_HEAD(&sub_api->sub_api_list);
58
59 mutex_lock(&subsystem_mutex);
60 list_for_each_entry(s, &subsystem_list, sub_api_list) {
61 if (!strcmp(s->name, sub_api->name)) {
62 pr_err("%p is already registered with"
63 " duplicate name %s, unable to process"
64 " request\n", s, s->name);
65 mutex_unlock(&subsystem_mutex);
66 return -EEXIST;
67 }
68 }
69 list_add_tail(&sub_api->sub_api_list, &subsystem_list);
70 mutex_unlock(&subsystem_mutex);
71
72 pr_debug("TCM: Registered subsystem plugin: %s struct module:"
73 " %p\n", sub_api->name, sub_api->owner);
74 return 0;
75}
76EXPORT_SYMBOL(transport_subsystem_register);
77
78void transport_subsystem_release(struct se_subsystem_api *sub_api)
79{
80 mutex_lock(&subsystem_mutex);
81 list_del(&sub_api->sub_api_list);
82 mutex_unlock(&subsystem_mutex);
83}
84EXPORT_SYMBOL(transport_subsystem_release);
85
86static struct se_subsystem_api *core_get_backend(const char *sub_name)
87{
88 struct se_subsystem_api *s;
89
90 mutex_lock(&subsystem_mutex);
91 list_for_each_entry(s, &subsystem_list, sub_api_list) {
92 if (!strcmp(s->name, sub_name))
93 goto found;
94 }
95 mutex_unlock(&subsystem_mutex);
96 return NULL;
97found:
98 if (s->owner && !try_module_get(s->owner))
99 s = NULL;
100 mutex_unlock(&subsystem_mutex);
101 return s;
102}
103
104struct se_hba *
105core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags)
106{
107 struct se_hba *hba;
108 int ret = 0;
109
110 hba = kzalloc(sizeof(*hba), GFP_KERNEL);
111 if (!hba) {
112 pr_err("Unable to allocate struct se_hba\n");
113 return ERR_PTR(-ENOMEM);
114 }
115
116 INIT_LIST_HEAD(&hba->hba_dev_list);
117 spin_lock_init(&hba->device_lock);
118 mutex_init(&hba->hba_access_mutex);
119
120 hba->hba_index = scsi_get_new_index(SCSI_INST_INDEX);
121 hba->hba_flags |= hba_flags;
122
123 hba->transport = core_get_backend(plugin_name);
124 if (!hba->transport) {
125 ret = -EINVAL;
126 goto out_free_hba;
127 }
128
129 ret = hba->transport->attach_hba(hba, plugin_dep_id);
130 if (ret < 0)
131 goto out_module_put;
132
133 spin_lock(&hba_lock);
134 hba->hba_id = hba_id_counter++;
135 list_add_tail(&hba->hba_node, &hba_list);
136 spin_unlock(&hba_lock);
137
138 pr_debug("CORE_HBA[%d] - Attached HBA to Generic Target"
139 " Core\n", hba->hba_id);
140
141 return hba;
142
143out_module_put:
144 if (hba->transport->owner)
145 module_put(hba->transport->owner);
146 hba->transport = NULL;
147out_free_hba:
148 kfree(hba);
149 return ERR_PTR(ret);
150}
151
152int
153core_delete_hba(struct se_hba *hba)
154{
155 if (!list_empty(&hba->hba_dev_list))
156 dump_stack();
157
158 hba->transport->detach_hba(hba);
159
160 spin_lock(&hba_lock);
161 list_del(&hba->hba_node);
162 spin_unlock(&hba_lock);
163
164 pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target"
165 " Core\n", hba->hba_id);
166
167 if (hba->transport->owner)
168 module_put(hba->transport->owner);
169
170 hba->transport = NULL;
171 kfree(hba);
172 return 0;
173}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * Filename: target_core_hba.c
4 *
5 * This file contains the TCM HBA Transport related functions.
6 *
7 * (c) Copyright 2003-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 ******************************************************************************/
12
13#include <linux/net.h>
14#include <linux/string.h>
15#include <linux/timer.h>
16#include <linux/slab.h>
17#include <linux/spinlock.h>
18#include <linux/in.h>
19#include <linux/module.h>
20#include <net/sock.h>
21#include <net/tcp.h>
22
23#include <target/target_core_base.h>
24#include <target/target_core_backend.h>
25#include <target/target_core_fabric.h>
26
27#include "target_core_internal.h"
28
29static LIST_HEAD(backend_list);
30static DEFINE_MUTEX(backend_mutex);
31
32static u32 hba_id_counter;
33
34static DEFINE_SPINLOCK(hba_lock);
35static LIST_HEAD(hba_list);
36
37
38int transport_backend_register(const struct target_backend_ops *ops)
39{
40 struct target_backend *tb, *old;
41
42 tb = kzalloc(sizeof(*tb), GFP_KERNEL);
43 if (!tb)
44 return -ENOMEM;
45 tb->ops = ops;
46
47 mutex_lock(&backend_mutex);
48 list_for_each_entry(old, &backend_list, list) {
49 if (!strcmp(old->ops->name, ops->name)) {
50 pr_err("backend %s already registered.\n", ops->name);
51 mutex_unlock(&backend_mutex);
52 kfree(tb);
53 return -EEXIST;
54 }
55 }
56 target_setup_backend_cits(tb);
57 list_add_tail(&tb->list, &backend_list);
58 mutex_unlock(&backend_mutex);
59
60 pr_debug("TCM: Registered subsystem plugin: %s struct module: %p\n",
61 ops->name, ops->owner);
62 return 0;
63}
64EXPORT_SYMBOL(transport_backend_register);
65
66void target_backend_unregister(const struct target_backend_ops *ops)
67{
68 struct target_backend *tb;
69
70 mutex_lock(&backend_mutex);
71 list_for_each_entry(tb, &backend_list, list) {
72 if (tb->ops == ops) {
73 list_del(&tb->list);
74 mutex_unlock(&backend_mutex);
75 /*
76 * Wait for any outstanding backend driver ->rcu_head
77 * callbacks to complete post TBO->free_device() ->
78 * call_rcu(), before allowing backend driver module
79 * unload of target_backend_ops->owner to proceed.
80 */
81 rcu_barrier();
82 kfree(tb);
83 return;
84 }
85 }
86 mutex_unlock(&backend_mutex);
87}
88EXPORT_SYMBOL(target_backend_unregister);
89
90static struct target_backend *core_get_backend(const char *name)
91{
92 struct target_backend *tb;
93
94 mutex_lock(&backend_mutex);
95 list_for_each_entry(tb, &backend_list, list) {
96 if (!strcmp(tb->ops->name, name))
97 goto found;
98 }
99 mutex_unlock(&backend_mutex);
100 return NULL;
101found:
102 if (tb->ops->owner && !try_module_get(tb->ops->owner))
103 tb = NULL;
104 mutex_unlock(&backend_mutex);
105 return tb;
106}
107
108struct se_hba *
109core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags)
110{
111 struct se_hba *hba;
112 int ret = 0;
113
114 hba = kzalloc(sizeof(*hba), GFP_KERNEL);
115 if (!hba) {
116 pr_err("Unable to allocate struct se_hba\n");
117 return ERR_PTR(-ENOMEM);
118 }
119
120 spin_lock_init(&hba->device_lock);
121 mutex_init(&hba->hba_access_mutex);
122
123 hba->hba_index = scsi_get_new_index(SCSI_INST_INDEX);
124 hba->hba_flags |= hba_flags;
125
126 hba->backend = core_get_backend(plugin_name);
127 if (!hba->backend) {
128 ret = -EINVAL;
129 goto out_free_hba;
130 }
131
132 ret = hba->backend->ops->attach_hba(hba, plugin_dep_id);
133 if (ret < 0)
134 goto out_module_put;
135
136 spin_lock(&hba_lock);
137 hba->hba_id = hba_id_counter++;
138 list_add_tail(&hba->hba_node, &hba_list);
139 spin_unlock(&hba_lock);
140
141 pr_debug("CORE_HBA[%d] - Attached HBA to Generic Target"
142 " Core\n", hba->hba_id);
143
144 return hba;
145
146out_module_put:
147 module_put(hba->backend->ops->owner);
148 hba->backend = NULL;
149out_free_hba:
150 kfree(hba);
151 return ERR_PTR(ret);
152}
153
154int
155core_delete_hba(struct se_hba *hba)
156{
157 WARN_ON(hba->dev_count);
158
159 hba->backend->ops->detach_hba(hba);
160
161 spin_lock(&hba_lock);
162 list_del(&hba->hba_node);
163 spin_unlock(&hba_lock);
164
165 pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target"
166 " Core\n", hba->hba_id);
167
168 module_put(hba->backend->ops->owner);
169
170 hba->backend = NULL;
171 kfree(hba);
172 return 0;
173}
174
175bool target_sense_desc_format(struct se_device *dev)
176{
177 return (dev) ? dev->transport->get_blocks(dev) > U32_MAX : false;
178}