// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <asm/mshyperv.h>

#include "mshv.h"
#include "mshv_root.h"

/*
 * Ports and connections are hypervisor struct used for inter-partition
 * communication. Port represents the source and connection represents
 * the destination. Partitions are responsible for managing the port and
 * connection ids.
 *
 */

#define PORTID_MIN      1
#define PORTID_MAX      INT_MAX

static DEFINE_IDR(port_table_idr);

void
mshv_port_table_fini(void)
{
        struct port_table_info *port_info;
        unsigned long i, tmp;

        idr_lock(&port_table_idr);
        if (!idr_is_empty(&port_table_idr)) {
                idr_for_each_entry_ul(&port_table_idr, port_info, tmp, i) {
                        port_info = idr_remove(&port_table_idr, i);
                        kfree_rcu(port_info, portbl_rcu);
                }
        }
        idr_unlock(&port_table_idr);
}

int
mshv_portid_alloc(struct port_table_info *info)
{
        int ret = 0;

        idr_lock(&port_table_idr);
        ret = idr_alloc(&port_table_idr, info, PORTID_MIN,
                        PORTID_MAX, GFP_KERNEL);
        idr_unlock(&port_table_idr);

        return ret;
}

void
mshv_portid_free(int port_id)
{
        struct port_table_info *info;

        idr_lock(&port_table_idr);
        info = idr_remove(&port_table_idr, port_id);
        WARN_ON(!info);
        idr_unlock(&port_table_idr);

        synchronize_rcu();
        kfree(info);
}

int
mshv_portid_lookup(int port_id, struct port_table_info *info)
{
        struct port_table_info *_info;
        int ret = -ENOENT;

        rcu_read_lock();
        _info = idr_find(&port_table_idr, port_id);
        rcu_read_unlock();

        if (_info) {
                *info = *_info;
                ret = 0;
        }

        return ret;
}