1 #include <linux/spinlock.h> 2 #include <linux/list.h> 3 #include <linux/module.h> 4 #include <target/iscsi/iscsi_transport.h> 5 6 static LIST_HEAD(g_transport_list); 7 static DEFINE_MUTEX(transport_mutex); 8 9 struct iscsit_transport *iscsit_get_transport(int type) 10 { 11 struct iscsit_transport *t; 12 13 mutex_lock(&transport_mutex); 14 list_for_each_entry(t, &g_transport_list, t_node) { 15 if (t->transport_type == type) { 16 if (t->owner && !try_module_get(t->owner)) { 17 t = NULL; 18 } 19 mutex_unlock(&transport_mutex); 20 return t; 21 } 22 } 23 mutex_unlock(&transport_mutex); 24 25 return NULL; 26 } 27 28 void iscsit_put_transport(struct iscsit_transport *t) 29 { 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); 56