Nicholas Bellinger | 3f99306 | 2013-03-06 21:53:26 -0800 | [diff] [blame^] | 1 | #include <linux/spinlock.h> |
| 2 | #include <linux/list.h> |
| 3 | #include <target/iscsi/iscsi_transport.h> |
| 4 | |
| 5 | static LIST_HEAD(g_transport_list); |
| 6 | static DEFINE_MUTEX(transport_mutex); |
| 7 | |
| 8 | struct iscsit_transport *iscsit_get_transport(int type) |
| 9 | { |
| 10 | struct iscsit_transport *t; |
| 11 | |
| 12 | mutex_lock(&transport_mutex); |
| 13 | list_for_each_entry(t, &g_transport_list, t_node) { |
| 14 | if (t->transport_type == type) { |
| 15 | if (t->owner && !try_module_get(t->owner)) { |
| 16 | t = NULL; |
| 17 | } |
| 18 | mutex_unlock(&transport_mutex); |
| 19 | return t; |
| 20 | } |
| 21 | } |
| 22 | mutex_unlock(&transport_mutex); |
| 23 | |
| 24 | return NULL; |
| 25 | } |
| 26 | |
| 27 | void iscsit_put_transport(struct iscsit_transport *t) |
| 28 | { |
| 29 | if (t->owner) |
| 30 | module_put(t->owner); |
| 31 | } |
| 32 | |
| 33 | int iscsit_register_transport(struct iscsit_transport *t) |
| 34 | { |
| 35 | INIT_LIST_HEAD(&t->t_node); |
| 36 | |
| 37 | mutex_lock(&transport_mutex); |
| 38 | list_add_tail(&t->t_node, &g_transport_list); |
| 39 | mutex_unlock(&transport_mutex); |
| 40 | |
| 41 | pr_debug("Registered iSCSI transport: %s\n", t->name); |
| 42 | |
| 43 | return 0; |
| 44 | } |
| 45 | EXPORT_SYMBOL(iscsit_register_transport); |
| 46 | |
| 47 | void iscsit_unregister_transport(struct iscsit_transport *t) |
| 48 | { |
| 49 | mutex_lock(&transport_mutex); |
| 50 | list_del(&t->t_node); |
| 51 | mutex_unlock(&transport_mutex); |
| 52 | |
| 53 | pr_debug("Unregistered iSCSI transport: %s\n", t->name); |
| 54 | } |
| 55 | EXPORT_SYMBOL(iscsit_unregister_transport); |