[mirror_ubuntu-artful-kernel.git] / drivers / connector / cn_queue.c

/*
 * 	cn_queue.c
 * 
 * 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 * All rights reserved.
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/suspend.h>
#include <linux/connector.h>
#include <linux/delay.h>

void cn_queue_wrapper(struct work_struct *work)
{
	struct cn_callback_entry *cbq =
		container_of(work, struct cn_callback_entry, work);
	struct cn_callback_data *d = &cbq->data;

	d->callback(d->callback_priv);

	d->destruct_data(d->ddata);
	d->ddata = NULL;

	kfree(d->free);
}

static struct cn_callback_entry *cn_queue_alloc_callback_entry(char *name, struct cb_id *id, void (*callback)(void *))
{
	struct cn_callback_entry *cbq;

	cbq = kzalloc(sizeof(*cbq), GFP_KERNEL);
	if (!cbq) {
		printk(KERN_ERR "Failed to create new callback queue.\n");
		return NULL;
	}

	snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name);
	memcpy(&cbq->id.id, id, sizeof(struct cb_id));
	cbq->data.callback = callback;
	
	INIT_WORK(&cbq->work, &cn_queue_wrapper);
	return cbq;
}

static void cn_queue_free_callback(struct cn_callback_entry *cbq)
{
	flush_workqueue(cbq->pdev->cn_queue);

	kfree(cbq);
}

int cn_cb_equal(struct cb_id *i1, struct cb_id *i2)
{
	return ((i1->idx == i2->idx) && (i1->val == i2->val));
}

int cn_queue_add_callback(struct cn_queue_dev *dev, char *name, struct cb_id *id, void (*callback)(void *))
{
	struct cn_callback_entry *cbq, *__cbq;
	int found = 0;

	cbq = cn_queue_alloc_callback_entry(name, id, callback);
	if (!cbq)
		return -ENOMEM;

	atomic_inc(&dev->refcnt);
	cbq->pdev = dev;

	spin_lock_bh(&dev->queue_lock);
	list_for_each_entry(__cbq, &dev->queue_list, callback_entry) {
		if (cn_cb_equal(&__cbq->id.id, id)) {
			found = 1;
			break;
		}
	}
	if (!found)
		list_add_tail(&cbq->callback_entry, &dev->queue_list);
	spin_unlock_bh(&dev->queue_lock);

	if (found) {
		atomic_dec(&dev->refcnt);
		cn_queue_free_callback(cbq);
		return -EINVAL;
	}

	cbq->nls = dev->nls;
	cbq->seq = 0;
	cbq->group = cbq->id.id.idx;

	return 0;
}

void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id)
{
	struct cn_callback_entry *cbq, *n;
	int found = 0;

	spin_lock_bh(&dev->queue_lock);
	list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) {
		if (cn_cb_equal(&cbq->id.id, id)) {
			list_del(&cbq->callback_entry);
			found = 1;
			break;
		}
	}
	spin_unlock_bh(&dev->queue_lock);

	if (found) {
		cn_queue_free_callback(cbq);
		atomic_dec(&dev->refcnt);
	}
}

struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *nls)
{
	struct cn_queue_dev *dev;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return NULL;

	snprintf(dev->name, sizeof(dev->name), "%s", name);
	atomic_set(&dev->refcnt, 0);
	INIT_LIST_HEAD(&dev->queue_list);
	spin_lock_init(&dev->queue_lock);

	dev->nls = nls;
	dev->netlink_groups = 0;

	dev->cn_queue = create_workqueue(dev->name);
	if (!dev->cn_queue) {
		kfree(dev);
		return NULL;
	}

	return dev;
}

void cn_queue_free_dev(struct cn_queue_dev *dev)
{
	struct cn_callback_entry *cbq, *n;

	flush_workqueue(dev->cn_queue);
	destroy_workqueue(dev->cn_queue);

	spin_lock_bh(&dev->queue_lock);
	list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry)
		list_del(&cbq->callback_entry);
	spin_unlock_bh(&dev->queue_lock);

	while (atomic_read(&dev->refcnt)) {
		printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
		       dev->name, atomic_read(&dev->refcnt));
		msleep(1000);
	}

	kfree(dev);
	dev = NULL;
}
Commit	Line	Data
7672d0b5 EP	1	/*
	2	* cn_queue.c
	3	*
	4	* 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
	5	* All rights reserved.
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*
	21	*/
	22
	23	#include <linux/kernel.h>
	24	#include <linux/module.h>
	25	#include <linux/list.h>
	26	#include <linux/workqueue.h>
	27	#include <linux/spinlock.h>
	28	#include <linux/slab.h>
	29	#include <linux/skbuff.h>
	30	#include <linux/suspend.h>
	31	#include <linux/connector.h>
	32	#include <linux/delay.h>
	33
c4028958	34	void cn_queue_wrapper(struct work_struct *work)
7672d0b5	35	{
c4028958	36	struct cn_callback_entry *cbq =
a240d9f1	37	container_of(work, struct cn_callback_entry, work);
c4028958	38	struct cn_callback_data *d = &cbq->data;
7672d0b5	39
acd042bb EP	40	d->callback(d->callback_priv);
	41
	42	d->destruct_data(d->ddata);
	43	d->ddata = NULL;
	44
	45	kfree(d->free);
7672d0b5 EP	46	}
7672d0b5 EP	47
acd042bb	48	static struct cn_callback_entry cn_queue_alloc_callback_entry(char name, struct cb_id id, void (callback)(void *))
7672d0b5 EP	49	{
	50	struct cn_callback_entry *cbq;
	51
	52	cbq = kzalloc(sizeof(*cbq), GFP_KERNEL);
	53	if (!cbq) {
	54	printk(KERN_ERR "Failed to create new callback queue.\n");
	55	return NULL;
	56	}
	57
acd042bb EP	58	snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name);
	59	memcpy(&cbq->id.id, id, sizeof(struct cb_id));
	60	cbq->data.callback = callback;
	61
a240d9f1	62	INIT_WORK(&cbq->work, &cn_queue_wrapper);
7672d0b5 EP	63	return cbq;
	64	}
	65
	66	static void cn_queue_free_callback(struct cn_callback_entry *cbq)
	67	{
7672d0b5 EP	68	flush_workqueue(cbq->pdev->cn_queue);
	69
	70	kfree(cbq);
	71	}
	72
	73	int cn_cb_equal(struct cb_id i1, struct cb_id i2)
	74	{
	75	return ((i1->idx == i2->idx) && (i1->val == i2->val));
	76	}
	77
acd042bb	78	int cn_queue_add_callback(struct cn_queue_dev dev, char name, struct cb_id id, void (callback)(void *))
7672d0b5 EP	79	{
	80	struct cn_callback_entry cbq, __cbq;
	81	int found = 0;
	82
acd042bb	83	cbq = cn_queue_alloc_callback_entry(name, id, callback);
7672d0b5 EP	84	if (!cbq)
	85	return -ENOMEM;
	86
	87	atomic_inc(&dev->refcnt);
	88	cbq->pdev = dev;
	89
	90	spin_lock_bh(&dev->queue_lock);
	91	list_for_each_entry(__cbq, &dev->queue_list, callback_entry) {
acd042bb	92	if (cn_cb_equal(&__cbq->id.id, id)) {
7672d0b5 EP	93	found = 1;
	94	break;
	95	}
	96	}
	97	if (!found)
	98	list_add_tail(&cbq->callback_entry, &dev->queue_list);
	99	spin_unlock_bh(&dev->queue_lock);
	100
	101	if (found) {
	102	atomic_dec(&dev->refcnt);
	103	cn_queue_free_callback(cbq);
	104	return -EINVAL;
	105	}
	106
	107	cbq->nls = dev->nls;
	108	cbq->seq = 0;
acd042bb	109	cbq->group = cbq->id.id.idx;
7672d0b5 EP	110
	111	return 0;
	112	}
	113
	114	void cn_queue_del_callback(struct cn_queue_dev dev, struct cb_id id)
	115	{
	116	struct cn_callback_entry cbq, n;
	117	int found = 0;
	118
	119	spin_lock_bh(&dev->queue_lock);
	120	list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) {
acd042bb	121	if (cn_cb_equal(&cbq->id.id, id)) {
7672d0b5 EP	122	list_del(&cbq->callback_entry);
	123	found = 1;
	124	break;
	125	}
	126	}
	127	spin_unlock_bh(&dev->queue_lock);
	128
	129	if (found) {
	130	cn_queue_free_callback(cbq);
cec6f7f3	131	atomic_dec(&dev->refcnt);
7672d0b5 EP	132	}
	133	}
	134
	135	struct cn_queue_dev cn_queue_alloc_dev(char name, struct sock *nls)
	136	{
	137	struct cn_queue_dev *dev;
	138
	139	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	140	if (!dev)
	141	return NULL;
	142
	143	snprintf(dev->name, sizeof(dev->name), "%s", name);
	144	atomic_set(&dev->refcnt, 0);
	145	INIT_LIST_HEAD(&dev->queue_list);
	146	spin_lock_init(&dev->queue_lock);
	147
	148	dev->nls = nls;
	149	dev->netlink_groups = 0;
	150
	151	dev->cn_queue = create_workqueue(dev->name);
	152	if (!dev->cn_queue) {
	153	kfree(dev);
	154	return NULL;
	155	}
	156
	157	return dev;
	158	}
	159
	160	void cn_queue_free_dev(struct cn_queue_dev *dev)
	161	{
	162	struct cn_callback_entry cbq, n;
	163
	164	flush_workqueue(dev->cn_queue);
	165	destroy_workqueue(dev->cn_queue);
	166
	167	spin_lock_bh(&dev->queue_lock);
	168	list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry)
	169	list_del(&cbq->callback_entry);
	170	spin_unlock_bh(&dev->queue_lock);
	171
	172	while (atomic_read(&dev->refcnt)) {
	173	printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
	174	dev->name, atomic_read(&dev->refcnt));
	175	msleep(1000);
	176	}
	177
	178	kfree(dev);
	179	dev = NULL;
	180	}