/*
 * Copyright (c) 2007-2012 Nicira, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 */

/*
 * Includes Inango Systems Ltd’s changes/modifications dated: 2021.
 * Changed/modified portions - Copyright (c) 2021 , Inango Systems Ltd.
 */

/*
  Includes MaxLinear's changes dated: 2021, 2022, 2023.
  Changed portions - Copyright 2021-2023 MaxLinear, Inc.
*/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/if_bridge.h>
#include <linux/rtnetlink.h>
#if IS_ENABLED(CONFIG_BRIDGE)
#include <net/br_compat.h>
#endif
#include "datapath.h"
#include "dp_sysfs.h"
#include "vport.h"

#ifdef CONFIG_SYSFS

struct brport_attribute {
	struct attribute	attr;
	ssize_t (*show)(struct vport *, char *);
	ssize_t (*store)(struct vport *, unsigned long);
};

#define BRPORT_ATTR(_name, _mode, _show, _store)		\
struct brport_attribute brport_attr_##_name = {		        \
	.attr = {.name = __stringify(_name),			\
		 .mode = _mode },				\
	.show	= _show,					\
	.store	= _store,					\
};

static ssize_t show_path_cost(struct vport *p, char *buf)
{
	unsigned long value = 0;

	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &value, IFLA_BRPORT_COST, GET_PARAMETER);
	return sprintf(buf, "%lu\n", value);
}

static ssize_t store_path_cost(struct vport *p, unsigned long v)
{
	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &v, IFLA_BRPORT_COST, SET_PARAMETER);
	return 0;
}
static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
		   show_path_cost, store_path_cost);

static ssize_t show_priority(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static ssize_t store_priority(struct vport *p, unsigned long v)
{
	return 0;
}
static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
			 show_priority, store_priority);

static ssize_t show_designated_root(struct vport *p, char *buf)
{
	return sprintf(buf, "0000.010203040506\n");
}
static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);

static ssize_t show_designated_bridge(struct vport *p, char *buf)
{
	return sprintf(buf, "0000.060504030201\n");
}
static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);

static ssize_t show_designated_port(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);

static ssize_t show_designated_cost(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);

static ssize_t show_port_id(struct vport *p, char *buf)
{
	return sprintf(buf, "0x%x\n", 0);
}
static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);

static ssize_t show_port_no(struct vport *p, char *buf)
{
	unsigned long value = 0;

	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &value, IFLA_BRPORT_NO, GET_PARAMETER);
	return sprintf(buf, "0x%lx\n", value);
}

static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);

static ssize_t show_change_ack(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);

static ssize_t show_config_pending(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);

static ssize_t show_port_state(struct vport *p, char *buf)
{
	unsigned long value = 0;

	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &value, IFLA_BRPORT_STATE, GET_PARAMETER);
	return sprintf(buf, "%lu\n", value);
}
static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);

static ssize_t show_message_age_timer(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);

static ssize_t show_forward_delay_timer(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);

static ssize_t show_hold_timer(struct vport *p, char *buf)
{
	return sprintf(buf, "%d\n", 0);
}
static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);

static ssize_t show_fastleave(struct vport *p, char *buf)
{
	unsigned long flag = 0;

#if IS_ENABLED(CONFIG_BRIDGE)
	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &flag, IFLA_BRPORT_FAST_LEAVE, GET_PARAMETER);
#endif

	return sprintf(buf, "%lu\n", flag);
}
static ssize_t store_fastleave(struct vport *p, unsigned long v)
{
	unsigned long val = !!v;
	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &val, IFLA_BRPORT_FAST_LEAVE, SET_PARAMETER);

	return 0;
}
static BRPORT_ATTR(fastleave, S_IRUGO | S_IWUSR, show_fastleave, store_fastleave);

static ssize_t show_hairpin_mode(struct vport *p, char *buf)
{
	unsigned long flag = 0;

#if IS_ENABLED(CONFIG_BRIDGE)
	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &flag, IFLA_BRPORT_MODE, GET_PARAMETER);
#endif

	return sprintf(buf, "%lu\n", flag);
}
static ssize_t store_hairpin_mode(struct vport *p, unsigned long v)
{
	v = !!v;
	if (ovs_dp_sysfs_hook)
		ovs_dp_sysfs_hook(p->dev, &v, IFLA_BRPORT_MODE, SET_PARAMETER);

	return 0;
}
static BRPORT_ATTR(hairpin_mode, S_IRUGO | S_IWUSR, show_hairpin_mode, store_hairpin_mode);

static struct brport_attribute *brport_attrs[] = {
	&brport_attr_path_cost,
	&brport_attr_priority,
	&brport_attr_port_id,
	&brport_attr_port_no,
	&brport_attr_designated_root,
	&brport_attr_designated_bridge,
	&brport_attr_designated_port,
	&brport_attr_designated_cost,
	&brport_attr_state,
	&brport_attr_change_ack,
	&brport_attr_config_pending,
	&brport_attr_message_age_timer,
	&brport_attr_forward_delay_timer,
	&brport_attr_hold_timer,
	&brport_attr_fastleave,
	&brport_attr_hairpin_mode,
	NULL
};

#define to_vport_attr(_at) container_of(_at, struct brport_attribute, attr)
#define to_vport(obj)	container_of(obj, struct vport, kobj)

static ssize_t brport_show(struct kobject *kobj,
			   struct attribute *attr, char *buf)
{
	struct brport_attribute *brport_attr = to_vport_attr(attr);
	struct vport *p = to_vport(kobj);
	return brport_attr->show(p, buf);
}

static ssize_t brport_store(struct kobject *kobj,
			    struct attribute *attr,
			    const char *buf, size_t count)
{
	struct vport *p = to_vport(kobj);
	ssize_t err = -EINVAL;
	unsigned long val;
	char *endp;
	struct brport_attribute *brport_attr = to_vport_attr(attr);

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;
	
	val = simple_strtoul(buf, &endp, 0);
	if (endp == buf)
		return -EINVAL;

	if (!rtnl_trylock())
		return restart_syscall();
	if (p)
		err = brport_attr->store(p, val);
	else
		err = -ENODEV;

	rtnl_unlock();

	return err ? err : count;
}

struct sysfs_ops ovs_brport_sysfs_ops = {
	.show = brport_show,
	.store = brport_store,
};

/*
 * Add sysfs entries to ethernet device added to a bridge.
 * Creates a brport subdirectory with bridge attributes.
 * Puts symlink in bridge's brport subdirectory
 */
int ovs_dp_sysfs_add_if(struct vport *p, struct vport *br)
{
	struct brport_attribute **a;
	int err;

	/* Create /sys/class/net/<devname>/brport directory. */
	if (!p->ops->get_kobj(p))
		return -ENOENT;

	err = kobject_add(&p->kobj, p->ops->get_kobj(p),
			  SYSFS_BRIDGE_PORT_ATTR);
	if (err)
		goto err;

	/* Create symlink from /sys/class/net/<devname>/brport/bridge to
	 * /sys/class/net/<bridgename>. */
	err = sysfs_create_link(&p->kobj, br->ops->get_kobj(br),
		SYSFS_BRIDGE_PORT_LINK); /* "bridge" */
	if (err)
		goto err_del;

	/* Populate /sys/class/net/<devname>/brport directory with files. */
	for (a = brport_attrs; *a; ++a) {
		err = sysfs_create_file(&p->kobj, &((*a)->attr));
		if (err)
			goto err_del;
	}

	/* Create symlink from /sys/class/net/<bridgename>/brif/<devname> to
	 * /sys/class/net/<devname>/brport.  */
	err = sysfs_create_link(br->ifobj, &p->kobj, p->ops->get_name(p));
	if (err)
		goto err_del;
	strcpy(p->linkname, p->ops->get_name(p));

	p->ifobj = br->ifobj;
	kobject_uevent(&p->kobj, KOBJ_ADD);

	return 0;

err_del:
	kobject_del(&p->kobj);
err:
	p->linkname[0] = 0;
	return err;
}

int ovs_dp_sysfs_del_if(struct vport *p)
{
	if (p->linkname[0]) {
		sysfs_remove_link(p->ifobj, p->linkname);
		kobject_uevent(&p->kobj, KOBJ_REMOVE);
		kobject_del(&p->kobj);
		p->linkname[0] = '\0';
	}
	return 0;
}
#else /* !CONFIG_SYSFS */
int ovs_dp_sysfs_add_if(struct vport *p) { return 0; }
int ovs_dp_sysfs_del_if(struct vport *p) { return 0; }
#endif /* !CONFIG_SYSFS */