Commit | Line | Data |
---|---|---|
c66ac9db NB |
1 | /******************************************************************************* |
2 | * Filename: target_core_hba.c | |
3 | * | |
e3d6f909 | 4 | * This file contains the TCM HBA Transport related functions. |
c66ac9db | 5 | * |
4c76251e | 6 | * (c) Copyright 2003-2013 Datera, Inc. |
c66ac9db NB |
7 | * |
8 | * Nicholas A. Bellinger <nab@kernel.org> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License as published by | |
12 | * the Free Software Foundation; either version 2 of the License, or | |
13 | * (at your option) any later version. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | * GNU General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU General Public License | |
21 | * along with this program; if not, write to the Free Software | |
22 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
23 | * | |
24 | ******************************************************************************/ | |
25 | ||
26 | #include <linux/net.h> | |
27 | #include <linux/string.h> | |
28 | #include <linux/timer.h> | |
29 | #include <linux/slab.h> | |
30 | #include <linux/spinlock.h> | |
c66ac9db | 31 | #include <linux/in.h> |
827509e3 | 32 | #include <linux/module.h> |
c66ac9db NB |
33 | #include <net/sock.h> |
34 | #include <net/tcp.h> | |
35 | ||
36 | #include <target/target_core_base.h> | |
c4795fb2 CH |
37 | #include <target/target_core_backend.h> |
38 | #include <target/target_core_fabric.h> | |
c66ac9db | 39 | |
e26d99ae | 40 | #include "target_core_internal.h" |
c66ac9db | 41 | |
0a06d430 CH |
42 | static LIST_HEAD(backend_list); |
43 | static DEFINE_MUTEX(backend_mutex); | |
c66ac9db | 44 | |
e3d6f909 AG |
45 | static u32 hba_id_counter; |
46 | ||
47 | static DEFINE_SPINLOCK(hba_lock); | |
48 | static LIST_HEAD(hba_list); | |
49 | ||
c66ac9db | 50 | |
0a06d430 CH |
51 | int transport_backend_register(const struct target_backend_ops *ops) |
52 | { | |
53 | struct target_backend *tb, *old; | |
54 | ||
55 | tb = kzalloc(sizeof(*tb), GFP_KERNEL); | |
56 | if (!tb) | |
57 | return -ENOMEM; | |
58 | tb->ops = ops; | |
59 | ||
60 | mutex_lock(&backend_mutex); | |
61 | list_for_each_entry(old, &backend_list, list) { | |
62 | if (!strcmp(old->ops->name, ops->name)) { | |
63 | pr_err("backend %s already registered.\n", ops->name); | |
64 | mutex_unlock(&backend_mutex); | |
65 | kfree(tb); | |
c66ac9db NB |
66 | return -EEXIST; |
67 | } | |
68 | } | |
0a06d430 CH |
69 | target_setup_backend_cits(tb); |
70 | list_add_tail(&tb->list, &backend_list); | |
71 | mutex_unlock(&backend_mutex); | |
c66ac9db | 72 | |
0a06d430 CH |
73 | pr_debug("TCM: Registered subsystem plugin: %s struct module: %p\n", |
74 | ops->name, ops->owner); | |
c66ac9db NB |
75 | return 0; |
76 | } | |
0a06d430 | 77 | EXPORT_SYMBOL(transport_backend_register); |
c66ac9db | 78 | |
0a06d430 | 79 | void target_backend_unregister(const struct target_backend_ops *ops) |
c66ac9db | 80 | { |
0a06d430 CH |
81 | struct target_backend *tb; |
82 | ||
83 | mutex_lock(&backend_mutex); | |
84 | list_for_each_entry(tb, &backend_list, list) { | |
85 | if (tb->ops == ops) { | |
86 | list_del(&tb->list); | |
94509182 NB |
87 | mutex_unlock(&backend_mutex); |
88 | /* | |
89 | * Wait for any outstanding backend driver ->rcu_head | |
90 | * callbacks to complete post TBO->free_device() -> | |
91 | * call_rcu(), before allowing backend driver module | |
92 | * unload of target_backend_ops->owner to proceed. | |
93 | */ | |
94 | rcu_barrier(); | |
0a06d430 | 95 | kfree(tb); |
94509182 | 96 | return; |
0a06d430 CH |
97 | } |
98 | } | |
99 | mutex_unlock(&backend_mutex); | |
c66ac9db | 100 | } |
0a06d430 | 101 | EXPORT_SYMBOL(target_backend_unregister); |
c66ac9db | 102 | |
0a06d430 | 103 | static struct target_backend *core_get_backend(const char *name) |
c66ac9db | 104 | { |
0a06d430 | 105 | struct target_backend *tb; |
c66ac9db | 106 | |
0a06d430 CH |
107 | mutex_lock(&backend_mutex); |
108 | list_for_each_entry(tb, &backend_list, list) { | |
109 | if (!strcmp(tb->ops->name, name)) | |
c66ac9db NB |
110 | goto found; |
111 | } | |
0a06d430 | 112 | mutex_unlock(&backend_mutex); |
c66ac9db NB |
113 | return NULL; |
114 | found: | |
0a06d430 CH |
115 | if (tb->ops->owner && !try_module_get(tb->ops->owner)) |
116 | tb = NULL; | |
117 | mutex_unlock(&backend_mutex); | |
118 | return tb; | |
c66ac9db NB |
119 | } |
120 | ||
121 | struct se_hba * | |
122 | core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags) | |
123 | { | |
124 | struct se_hba *hba; | |
125 | int ret = 0; | |
126 | ||
127 | hba = kzalloc(sizeof(*hba), GFP_KERNEL); | |
128 | if (!hba) { | |
6708bb27 | 129 | pr_err("Unable to allocate struct se_hba\n"); |
c66ac9db NB |
130 | return ERR_PTR(-ENOMEM); |
131 | } | |
132 | ||
c66ac9db | 133 | spin_lock_init(&hba->device_lock); |
c66ac9db NB |
134 | mutex_init(&hba->hba_access_mutex); |
135 | ||
136 | hba->hba_index = scsi_get_new_index(SCSI_INST_INDEX); | |
137 | hba->hba_flags |= hba_flags; | |
138 | ||
0a06d430 CH |
139 | hba->backend = core_get_backend(plugin_name); |
140 | if (!hba->backend) { | |
c66ac9db NB |
141 | ret = -EINVAL; |
142 | goto out_free_hba; | |
143 | } | |
144 | ||
0a06d430 | 145 | ret = hba->backend->ops->attach_hba(hba, plugin_dep_id); |
c66ac9db NB |
146 | if (ret < 0) |
147 | goto out_module_put; | |
148 | ||
e3d6f909 AG |
149 | spin_lock(&hba_lock); |
150 | hba->hba_id = hba_id_counter++; | |
151 | list_add_tail(&hba->hba_node, &hba_list); | |
152 | spin_unlock(&hba_lock); | |
c66ac9db | 153 | |
6708bb27 | 154 | pr_debug("CORE_HBA[%d] - Attached HBA to Generic Target" |
c66ac9db NB |
155 | " Core\n", hba->hba_id); |
156 | ||
157 | return hba; | |
158 | ||
159 | out_module_put: | |
0a06d430 CH |
160 | module_put(hba->backend->ops->owner); |
161 | hba->backend = NULL; | |
c66ac9db NB |
162 | out_free_hba: |
163 | kfree(hba); | |
164 | return ERR_PTR(ret); | |
165 | } | |
166 | ||
167 | int | |
168 | core_delete_hba(struct se_hba *hba) | |
169 | { | |
0fd97ccf | 170 | WARN_ON(hba->dev_count); |
c66ac9db | 171 | |
0a06d430 | 172 | hba->backend->ops->detach_hba(hba); |
c66ac9db | 173 | |
e3d6f909 AG |
174 | spin_lock(&hba_lock); |
175 | list_del(&hba->hba_node); | |
176 | spin_unlock(&hba_lock); | |
c66ac9db | 177 | |
6708bb27 | 178 | pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target" |
c66ac9db NB |
179 | " Core\n", hba->hba_id); |
180 | ||
0a06d430 | 181 | module_put(hba->backend->ops->owner); |
c66ac9db | 182 | |
0a06d430 | 183 | hba->backend = NULL; |
c66ac9db NB |
184 | kfree(hba); |
185 | return 0; | |
186 | } | |
4e4937e8 SG |
187 | |
188 | bool target_sense_desc_format(struct se_device *dev) | |
189 | { | |
f3bb467f | 190 | return (dev) ? dev->transport->get_blocks(dev) > U32_MAX : false; |
4e4937e8 | 191 | } |