162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0 262306a36Sopenharmony_ci#include <linux/spinlock.h> 362306a36Sopenharmony_ci#include <linux/list.h> 462306a36Sopenharmony_ci#include <linux/module.h> 562306a36Sopenharmony_ci#include <target/iscsi/iscsi_transport.h> 662306a36Sopenharmony_ci 762306a36Sopenharmony_cistatic LIST_HEAD(g_transport_list); 862306a36Sopenharmony_cistatic DEFINE_MUTEX(transport_mutex); 962306a36Sopenharmony_ci 1062306a36Sopenharmony_cistruct iscsit_transport *iscsit_get_transport(int type) 1162306a36Sopenharmony_ci{ 1262306a36Sopenharmony_ci struct iscsit_transport *t; 1362306a36Sopenharmony_ci 1462306a36Sopenharmony_ci mutex_lock(&transport_mutex); 1562306a36Sopenharmony_ci list_for_each_entry(t, &g_transport_list, t_node) { 1662306a36Sopenharmony_ci if (t->transport_type == type) { 1762306a36Sopenharmony_ci if (t->owner && !try_module_get(t->owner)) { 1862306a36Sopenharmony_ci t = NULL; 1962306a36Sopenharmony_ci } 2062306a36Sopenharmony_ci mutex_unlock(&transport_mutex); 2162306a36Sopenharmony_ci return t; 2262306a36Sopenharmony_ci } 2362306a36Sopenharmony_ci } 2462306a36Sopenharmony_ci mutex_unlock(&transport_mutex); 2562306a36Sopenharmony_ci 2662306a36Sopenharmony_ci return NULL; 2762306a36Sopenharmony_ci} 2862306a36Sopenharmony_ci 2962306a36Sopenharmony_civoid iscsit_put_transport(struct iscsit_transport *t) 3062306a36Sopenharmony_ci{ 3162306a36Sopenharmony_ci module_put(t->owner); 3262306a36Sopenharmony_ci} 3362306a36Sopenharmony_ci 3462306a36Sopenharmony_civoid iscsit_register_transport(struct iscsit_transport *t) 3562306a36Sopenharmony_ci{ 3662306a36Sopenharmony_ci INIT_LIST_HEAD(&t->t_node); 3762306a36Sopenharmony_ci 3862306a36Sopenharmony_ci mutex_lock(&transport_mutex); 3962306a36Sopenharmony_ci list_add_tail(&t->t_node, &g_transport_list); 4062306a36Sopenharmony_ci mutex_unlock(&transport_mutex); 4162306a36Sopenharmony_ci 4262306a36Sopenharmony_ci pr_debug("Registered iSCSI transport: %s\n", t->name); 4362306a36Sopenharmony_ci} 4462306a36Sopenharmony_ciEXPORT_SYMBOL(iscsit_register_transport); 4562306a36Sopenharmony_ci 4662306a36Sopenharmony_civoid iscsit_unregister_transport(struct iscsit_transport *t) 4762306a36Sopenharmony_ci{ 4862306a36Sopenharmony_ci mutex_lock(&transport_mutex); 4962306a36Sopenharmony_ci list_del(&t->t_node); 5062306a36Sopenharmony_ci mutex_unlock(&transport_mutex); 5162306a36Sopenharmony_ci 5262306a36Sopenharmony_ci pr_debug("Unregistered iSCSI transport: %s\n", t->name); 5362306a36Sopenharmony_ci} 5462306a36Sopenharmony_ciEXPORT_SYMBOL(iscsit_unregister_transport); 55