// SPDX-License-Identifier: GPL-2.0
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/module.h>
#include <target/iscsi/iscsi_transport.h>

static LIST_HEAD(g_transport_list);
static DEFINE_MUTEX(transport_mutex);

struct iscsit_transport *iscsit_get_transport(int type)
{
        struct iscsit_transport *t;

        mutex_lock(&transport_mutex);
        list_for_each_entry(t, &g_transport_list, t_node) {
                if (t->transport_type == type) {
                        if (t->owner && !try_module_get(t->owner)) {
                                t = NULL;
                        }
                        mutex_unlock(&transport_mutex);
                        return t;
                }
        }
        mutex_unlock(&transport_mutex);

        return NULL;
}

void iscsit_put_transport(struct iscsit_transport *t)
{
        module_put(t->owner);
}

void iscsit_register_transport(struct iscsit_transport *t)
{
        INIT_LIST_HEAD(&t->t_node);

        mutex_lock(&transport_mutex);
        list_add_tail(&t->t_node, &g_transport_list);
        mutex_unlock(&transport_mutex);

        pr_debug("Registered iSCSI transport: %s\n", t->name);
}
EXPORT_SYMBOL(iscsit_register_transport);

void iscsit_unregister_transport(struct iscsit_transport *t)
{
        mutex_lock(&transport_mutex);
        list_del(&t->t_node);
        mutex_unlock(&transport_mutex);

        pr_debug("Unregistered iSCSI transport: %s\n", t->name);
}
EXPORT_SYMBOL(iscsit_unregister_transport);