| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | #include <linux/spinlock.h> |
| 3 | #include <linux/list.h> |
| 4 | #include <linux/module.h> |
| 5 | #include <target/iscsi/iscsi_transport.h> |
| 6 | |
| 7 | static LIST_HEAD(g_transport_list); |
| 8 | static DEFINE_MUTEX(transport_mutex); |
| 9 | |
| 10 | struct iscsit_transport *iscsit_get_transport(int type) |
| 11 | { |
| 12 | struct iscsit_transport *t; |
| 13 | |
| 14 | mutex_lock(&transport_mutex); |
| 15 | list_for_each_entry(t, &g_transport_list, t_node) { |
| 16 | if (t->transport_type == type) { |
| 17 | if (t->owner && !try_module_get(module: t->owner)) { |
| 18 | t = NULL; |
| 19 | } |
| 20 | mutex_unlock(lock: &transport_mutex); |
| 21 | return t; |
| 22 | } |
| 23 | } |
| 24 | mutex_unlock(lock: &transport_mutex); |
| 25 | |
| 26 | return NULL; |
| 27 | } |
| 28 | |
| 29 | void iscsit_put_transport(struct iscsit_transport *t) |
| 30 | { |
| 31 | module_put(module: t->owner); |
| 32 | } |
| 33 | |
| 34 | void iscsit_register_transport(struct iscsit_transport *t) |
| 35 | { |
| 36 | INIT_LIST_HEAD(list: &t->t_node); |
| 37 | |
| 38 | mutex_lock(&transport_mutex); |
| 39 | list_add_tail(new: &t->t_node, head: &g_transport_list); |
| 40 | mutex_unlock(lock: &transport_mutex); |
| 41 | |
| 42 | pr_debug("Registered iSCSI transport: %s\n", t->name); |
| 43 | } |
| 44 | EXPORT_SYMBOL(iscsit_register_transport); |
| 45 | |
| 46 | void iscsit_unregister_transport(struct iscsit_transport *t) |
| 47 | { |
| 48 | mutex_lock(&transport_mutex); |
| 49 | list_del(entry: &t->t_node); |
| 50 | mutex_unlock(lock: &transport_mutex); |
| 51 | |
| 52 | pr_debug("Unregistered iSCSI transport: %s\n", t->name); |
| 53 | } |
| 54 | EXPORT_SYMBOL(iscsit_unregister_transport); |
| 55 |