blob: 3dd1bd4b6f71c712eb10770ebf976a9a7fa67cfc [file] [log] [blame]
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -08001/*******************************************************************************
2 * Filename: target_core_hba.c
3 *
Andy Grovere3d6f902011-07-19 08:55:10 +00004 * This file contains the TCM HBA Transport related functions.
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -08005 *
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>
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080034#include <linux/in.h>
Paul Gortmaker827509e2011-08-30 14:20:44 -040035#include <linux/module.h>
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080036#include <net/sock.h>
37#include <net/tcp.h>
38
39#include <target/target_core_base.h>
Christoph Hellwigc4795fb2011-11-16 09:46:48 -050040#include <target/target_core_backend.h>
41#include <target/target_core_fabric.h>
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080042
Christoph Hellwige26d99a2011-11-14 12:30:30 -050043#include "target_core_internal.h"
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080044
45static LIST_HEAD(subsystem_list);
46static DEFINE_MUTEX(subsystem_mutex);
47
Andy Grovere3d6f902011-07-19 08:55:10 +000048static u32 hba_id_counter;
49
50static DEFINE_SPINLOCK(hba_lock);
51static LIST_HEAD(hba_list);
52
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080053int 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) {
Andy Grover6708bb22011-06-08 10:36:43 -070061 if (!strcmp(s->name, sub_api->name)) {
62 pr_err("%p is already registered with"
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080063 " 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
Andy Grover6708bb22011-06-08 10:36:43 -070072 pr_debug("TCM: Registered subsystem plugin: %s struct module:"
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -080073 " %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) {
Andy Grover6708bb22011-06-08 10:36:43 -0700112 pr_err("Unable to allocate struct se_hba\n");
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800113 return ERR_PTR(-ENOMEM);
114 }
115
116 INIT_LIST_HEAD(&hba->hba_dev_list);
117 spin_lock_init(&hba->device_lock);
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800118 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
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800123 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
Andy Grovere3d6f902011-07-19 08:55:10 +0000133 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);
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800137
Andy Grover6708bb22011-06-08 10:36:43 -0700138 pr_debug("CORE_HBA[%d] - Attached HBA to Generic Target"
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800139 " 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{
Fubo Chen05aea6e2011-03-14 04:06:00 -0700155 if (!list_empty(&hba->hba_dev_list))
156 dump_stack();
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800157
158 hba->transport->detach_hba(hba);
159
Andy Grovere3d6f902011-07-19 08:55:10 +0000160 spin_lock(&hba_lock);
161 list_del(&hba->hba_node);
162 spin_unlock(&hba_lock);
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800163
Andy Grover6708bb22011-06-08 10:36:43 -0700164 pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target"
Nicholas Bellingerc66ac9d2010-12-17 11:11:26 -0800165 " 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}