/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* connector.h
*
* 2004-2005 Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
* All rights reserved.
*/
#ifndef __CONNECTOR_H
#define __CONNECTOR_H
#include <linux/refcount.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <net/sock.h>
#include <uapi/linux/connector.h>
#define CN_CBQ_NAMELEN 32
struct cn_queue_dev {
atomic_t refcnt;
unsigned char name[CN_CBQ_NAMELEN];
struct list_head queue_list;
spinlock_t queue_lock;
struct sock *nls;
};
struct cn_callback_id {
unsigned char name[CN_CBQ_NAMELEN];
struct cb_id id;
};
struct cn_callback_entry {
struct list_head callback_entry;
refcount_t refcnt;
struct cn_queue_dev *pdev;
struct cn_callback_id id;
void (*callback) (struct cn_msg *, struct netlink_skb_parms *);
u32 seq, group;
};
struct cn_dev {
struct cb_id id;
u32 seq, groups;
struct sock *nls;
struct cn_queue_dev *cbdev;
};
/**
* cn_add_callback() - Registers new callback with connector core.
*
* @id: unique connector's user identifier.
* It must be registered in connector.h for legal
* in-kernel users.
* @name: connector's callback symbolic name.
* @callback: connector's callback.
* parameters are %cn_msg and the sender's credentials
*/
int cn_add_callback(struct cb_id *id, const char *name,
void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
/**
* cn_del_callback() - Unregisters new callback with connector core.
*
* @id: unique connector's user identifier.
*/
void cn_del_callback(struct cb_id *id);
/**
* cn_netlink_send_mult - Sends message to the specified groups.
*
* @msg: message header(with attached data).
* @len: Number of @msg to be sent.
* @portid: destination port.
* If non-zero the message will be sent to the given port,
* which should be set to the original sender.
* @group: destination group.
* If @portid and @group is zero, then appropriate group will
* be searched through all registered connector users, and
* message will be delivered to the group which was created
* for user with the same ID as in @msg.
* If @group is not zero, then message will be delivered
* to the specified group.
* @gfp_mask: GFP mask.
*
* It can be safely called from softirq context, but may silently
* fail under strong memory pressure.
*
* If there are no listeners for given group %-ESRCH can be returned.
*/
int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, u32 group, gfp_t gfp_mask);
/**
* cn_netlink_send_mult - Sends message to the specified groups.
*
* @msg: message header(with attached data).
* @portid: destination port.
* If non-zero the message will be sent to the given port,
* which should be set to the original sender.
* @group: destination group.
* If @portid and @group is zero, then appropriate group will
* be searched through all registered connector users, and
* message will be delivered to the group which was created
* for user with the same ID as in @msg.
* If @group is not zero, then message will be delivered
* to the specified group.
* @gfp_mask: GFP mask.
*
* It can be safely called from softirq context, but may silently
* fail under strong memory pressure.
*
* If there are no listeners for given group %-ESRCH can be returned.
*/
int cn_netlink_send(struct cn_msg *msg, u32 portid, u32 group, gfp_t gfp_mask);
int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name,
struct cb_id *id,
void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id);
void cn_queue_release_callback(struct cn_callback_entry *);
struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *);
void cn_queue_free_dev(struct cn_queue_dev *dev);
int cn_cb_equal(struct cb_id *, struct cb_id *);
#endif /* __CONNECTOR_H */
