18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0 28c2ecf20Sopenharmony_ci#include <linux/spinlock.h> 38c2ecf20Sopenharmony_ci#include <linux/list.h> 48c2ecf20Sopenharmony_ci#include <linux/module.h> 58c2ecf20Sopenharmony_ci#include <target/iscsi/iscsi_transport.h> 68c2ecf20Sopenharmony_ci 78c2ecf20Sopenharmony_cistatic LIST_HEAD(g_transport_list); 88c2ecf20Sopenharmony_cistatic DEFINE_MUTEX(transport_mutex); 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_cistruct iscsit_transport *iscsit_get_transport(int type) 118c2ecf20Sopenharmony_ci{ 128c2ecf20Sopenharmony_ci struct iscsit_transport *t; 138c2ecf20Sopenharmony_ci 148c2ecf20Sopenharmony_ci mutex_lock(&transport_mutex); 158c2ecf20Sopenharmony_ci list_for_each_entry(t, &g_transport_list, t_node) { 168c2ecf20Sopenharmony_ci if (t->transport_type == type) { 178c2ecf20Sopenharmony_ci if (t->owner && !try_module_get(t->owner)) { 188c2ecf20Sopenharmony_ci t = NULL; 198c2ecf20Sopenharmony_ci } 208c2ecf20Sopenharmony_ci mutex_unlock(&transport_mutex); 218c2ecf20Sopenharmony_ci return t; 228c2ecf20Sopenharmony_ci } 238c2ecf20Sopenharmony_ci } 248c2ecf20Sopenharmony_ci mutex_unlock(&transport_mutex); 258c2ecf20Sopenharmony_ci 268c2ecf20Sopenharmony_ci return NULL; 278c2ecf20Sopenharmony_ci} 288c2ecf20Sopenharmony_ci 298c2ecf20Sopenharmony_civoid iscsit_put_transport(struct iscsit_transport *t) 308c2ecf20Sopenharmony_ci{ 318c2ecf20Sopenharmony_ci module_put(t->owner); 328c2ecf20Sopenharmony_ci} 338c2ecf20Sopenharmony_ci 348c2ecf20Sopenharmony_civoid iscsit_register_transport(struct iscsit_transport *t) 358c2ecf20Sopenharmony_ci{ 368c2ecf20Sopenharmony_ci INIT_LIST_HEAD(&t->t_node); 378c2ecf20Sopenharmony_ci 388c2ecf20Sopenharmony_ci mutex_lock(&transport_mutex); 398c2ecf20Sopenharmony_ci list_add_tail(&t->t_node, &g_transport_list); 408c2ecf20Sopenharmony_ci mutex_unlock(&transport_mutex); 418c2ecf20Sopenharmony_ci 428c2ecf20Sopenharmony_ci pr_debug("Registered iSCSI transport: %s\n", t->name); 438c2ecf20Sopenharmony_ci} 448c2ecf20Sopenharmony_ciEXPORT_SYMBOL(iscsit_register_transport); 458c2ecf20Sopenharmony_ci 468c2ecf20Sopenharmony_civoid iscsit_unregister_transport(struct iscsit_transport *t) 478c2ecf20Sopenharmony_ci{ 488c2ecf20Sopenharmony_ci mutex_lock(&transport_mutex); 498c2ecf20Sopenharmony_ci list_del(&t->t_node); 508c2ecf20Sopenharmony_ci mutex_unlock(&transport_mutex); 518c2ecf20Sopenharmony_ci 528c2ecf20Sopenharmony_ci pr_debug("Unregistered iSCSI transport: %s\n", t->name); 538c2ecf20Sopenharmony_ci} 548c2ecf20Sopenharmony_ciEXPORT_SYMBOL(iscsit_unregister_transport); 55