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/*
* Copyright (C) 2013-2015 Kay Sievers
* Copyright (C) 2013-2015 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Copyright (C) 2013-2015 Daniel Mack <daniel@zonque.org>
* Copyright (C) 2013-2015 David Herrmann <dh.herrmann@gmail.com>
* Copyright (C) 2013-2015 Linux Foundation
* Copyright (C) 2014-2015 Djalal Harouni <tixxdz@opendz.org>
*
* kdbus is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*/
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include "bus.h"
#include "connection.h"
#include "domain.h"
#include "endpoint.h"
#include "item.h"
#include "message.h"
#include "notify.h"
static inline void kdbus_notify_add_tail(struct kdbus_kmsg *kmsg,
struct kdbus_bus *bus)
{
spin_lock(&bus->notify_lock);
list_add_tail(&kmsg->notify_entry, &bus->notify_list);
spin_unlock(&bus->notify_lock);
}
static int kdbus_notify_reply(struct kdbus_bus *bus, u64 id,
u64 cookie, u64 msg_type)
{
struct kdbus_kmsg *kmsg = NULL;
WARN_ON(id == 0);
kmsg = kdbus_kmsg_new(bus, 0);
if (IS_ERR(kmsg))
return PTR_ERR(kmsg);
/*
* a kernel-generated notification can only contain one
* struct kdbus_item, so make a shortcut here for
* faster lookup in the match db.
*/
kmsg->notify_type = msg_type;
kmsg->msg.flags = KDBUS_MSG_SIGNAL;
kmsg->msg.dst_id = id;
kmsg->msg.src_id = KDBUS_SRC_ID_KERNEL;
kmsg->msg.payload_type = KDBUS_PAYLOAD_KERNEL;
kmsg->msg.cookie_reply = cookie;
kmsg->msg.items[0].type = msg_type;
kdbus_notify_add_tail(kmsg, bus);
return 0;
}
/**
* kdbus_notify_reply_timeout() - queue a timeout reply
* @bus: Bus which queues the messages
* @id: The destination's connection ID
* @cookie: The cookie to set in the reply.
*
* Queues a message that has a KDBUS_ITEM_REPLY_TIMEOUT item attached.
*
* Return: 0 on success, negative errno on failure.
*/
int kdbus_notify_reply_timeout(struct kdbus_bus *bus, u64 id, u64 cookie)
{
return kdbus_notify_reply(bus, id, cookie, KDBUS_ITEM_REPLY_TIMEOUT);
}
/**
* kdbus_notify_reply_dead() - queue a 'dead' reply
* @bus: Bus which queues the messages
* @id: The destination's connection ID
* @cookie: The cookie to set in the reply.
*
* Queues a message that has a KDBUS_ITEM_REPLY_DEAD item attached.
*
* Return: 0 on success, negative errno on failure.
*/
int kdbus_notify_reply_dead(struct kdbus_bus *bus, u64 id, u64 cookie)
{
return kdbus_notify_reply(bus, id, cookie, KDBUS_ITEM_REPLY_DEAD);
}
/**
* kdbus_notify_name_change() - queue a notification about a name owner change
* @bus: Bus which queues the messages
* @type: The type if the notification; KDBUS_ITEM_NAME_ADD,
* KDBUS_ITEM_NAME_CHANGE or KDBUS_ITEM_NAME_REMOVE
* @old_id: The id of the connection that used to own the name
* @new_id: The id of the new owner connection
* @old_flags: The flags to pass in the KDBUS_ITEM flags field for
* the old owner
* @new_flags: The flags to pass in the KDBUS_ITEM flags field for
* the new owner
* @name: The name that was removed or assigned to a new owner
*
* Return: 0 on success, negative errno on failure.
*/
int kdbus_notify_name_change(struct kdbus_bus *bus, u64 type,
u64 old_id, u64 new_id,
u64 old_flags, u64 new_flags,
const char *name)
{
struct kdbus_kmsg *kmsg = NULL;
size_t name_len, extra_size;
name_len = strlen(name) + 1;
extra_size = sizeof(struct kdbus_notify_name_change) + name_len;
kmsg = kdbus_kmsg_new(bus, extra_size);
if (IS_ERR(kmsg))
return PTR_ERR(kmsg);
kmsg->msg.flags = KDBUS_MSG_SIGNAL;
kmsg->msg.dst_id = KDBUS_DST_ID_BROADCAST;
kmsg->msg.src_id = KDBUS_SRC_ID_KERNEL;
kmsg->msg.payload_type = KDBUS_PAYLOAD_KERNEL;
kmsg->notify_type = type;
kmsg->notify_old_id = old_id;
kmsg->notify_new_id = new_id;
kmsg->msg.items[0].type = type;
kmsg->msg.items[0].name_change.old_id.id = old_id;
kmsg->msg.items[0].name_change.old_id.flags = old_flags;
kmsg->msg.items[0].name_change.new_id.id = new_id;
kmsg->msg.items[0].name_change.new_id.flags = new_flags;
memcpy(kmsg->msg.items[0].name_change.name, name, name_len);
kmsg->notify_name = kmsg->msg.items[0].name_change.name;
kdbus_notify_add_tail(kmsg, bus);
return 0;
}
/**
* kdbus_notify_id_change() - queue a notification about a unique ID change
* @bus: Bus which queues the messages
* @type: The type if the notification; KDBUS_ITEM_ID_ADD or
* KDBUS_ITEM_ID_REMOVE
* @id: The id of the connection that was added or removed
* @flags: The flags to pass in the KDBUS_ITEM flags field
*
* Return: 0 on success, negative errno on failure.
*/
int kdbus_notify_id_change(struct kdbus_bus *bus, u64 type, u64 id, u64 flags)
{
struct kdbus_kmsg *kmsg = NULL;
kmsg = kdbus_kmsg_new(bus, sizeof(struct kdbus_notify_id_change));
if (IS_ERR(kmsg))
return PTR_ERR(kmsg);
kmsg->msg.flags = KDBUS_MSG_SIGNAL;
kmsg->msg.dst_id = KDBUS_DST_ID_BROADCAST;
kmsg->msg.src_id = KDBUS_SRC_ID_KERNEL;
kmsg->msg.payload_type = KDBUS_PAYLOAD_KERNEL;
kmsg->notify_type = type;
switch (type) {
case KDBUS_ITEM_ID_ADD:
kmsg->notify_new_id = id;
break;
case KDBUS_ITEM_ID_REMOVE:
kmsg->notify_old_id = id;
break;
default:
BUG();
}
kmsg->msg.items[0].type = type;
kmsg->msg.items[0].id_change.id = id;
kmsg->msg.items[0].id_change.flags = flags;
kdbus_notify_add_tail(kmsg, bus);
return 0;
}
/**
* kdbus_notify_flush() - send a list of collected messages
* @bus: Bus which queues the messages
*
* The list is empty after sending the messages.
*/
void kdbus_notify_flush(struct kdbus_bus *bus)
{
LIST_HEAD(notify_list);
struct kdbus_kmsg *kmsg, *tmp;
mutex_lock(&bus->notify_flush_lock);
down_read(&bus->name_registry->rwlock);
spin_lock(&bus->notify_lock);
list_splice_init(&bus->notify_list, &notify_list);
spin_unlock(&bus->notify_lock);
list_for_each_entry_safe(kmsg, tmp, &notify_list, notify_entry) {
kdbus_meta_conn_collect(kmsg->conn_meta, kmsg, NULL,
KDBUS_ATTACH_TIMESTAMP);
if (kmsg->msg.dst_id != KDBUS_DST_ID_BROADCAST) {
struct kdbus_conn *conn;
conn = kdbus_bus_find_conn_by_id(bus, kmsg->msg.dst_id);
if (conn) {
kdbus_bus_eavesdrop(bus, NULL, kmsg);
kdbus_conn_entry_insert(NULL, conn, kmsg, NULL);
kdbus_conn_unref(conn);
}
} else {
kdbus_bus_broadcast(bus, NULL, kmsg);
}
list_del(&kmsg->notify_entry);
kdbus_kmsg_free(kmsg);
}
up_read(&bus->name_registry->rwlock);
mutex_unlock(&bus->notify_flush_lock);
}
/**
* kdbus_notify_free() - free a list of collected messages
* @bus: Bus which queues the messages
*/
void kdbus_notify_free(struct kdbus_bus *bus)
{
struct kdbus_kmsg *kmsg, *tmp;
list_for_each_entry_safe(kmsg, tmp, &bus->notify_list, notify_entry) {
list_del(&kmsg->notify_entry);
kdbus_kmsg_free(kmsg);
}
}