drivers/w1/w1_netlink.c - fp2-dev/kernel/msm - Gitiles

 /*
  * w1_netlink.c
  *
  * Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
  *
  *
  * 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/skbuff.h>
 #include <linux/netlink.h>
 #include <linux/connector.h>

 #include "w1.h"
 #include "w1_log.h"
 #include "w1_netlink.h"

 #if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
 {
 	char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
 	struct cn_msg *m = (struct cn_msg *)buf;
 	struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1);

 	memset(buf, 0, sizeof(buf));

 	m->id.idx = CN_W1_IDX;
 	m->id.val = CN_W1_VAL;

 	m->seq = dev->seq++;
 	m->len = sizeof(struct w1_netlink_msg);

 	memcpy(w, msg, sizeof(struct w1_netlink_msg));

 	cn_netlink_send(m, 0, GFP_KERNEL);
 }

 static void w1_send_slave(struct w1_master *dev, u64 rn)
 {
 	struct cn_msg *msg = dev->priv;
 	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 	int avail;

 	avail = dev->priv_size - cmd->len;

 	if (avail > 8) {
 		u64 *data = (void *)(cmd + 1) + cmd->len;

 		*data = rn;
 		cmd->len += 8;
 		hdr->len += 8;
 		msg->len += 8;
 		return;
 	}

 	msg->ack++;
 	cn_netlink_send(msg, 0, GFP_KERNEL);

 	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
 	hdr->len = sizeof(struct w1_netlink_cmd);
 	cmd->len = 0;
 }

 static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg,
 		unsigned int avail)
 {
 	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 	int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH;

 	dev->priv = msg;
 	dev->priv_size = avail;

 	w1_search_devices(dev, search_type, w1_send_slave);

 	msg->ack = 0;
 	cn_netlink_send(msg, 0, GFP_KERNEL);

 	dev->priv = NULL;
 	dev->priv_size = 0;

 	return 0;
 }

 static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr,
 		struct w1_netlink_cmd *cmd)
 {
 	void *data;
 	struct w1_netlink_msg *h;
 	struct w1_netlink_cmd *c;
 	struct cn_msg *cm;
 	int err;

 	data = kzalloc(sizeof(struct cn_msg) +
 			sizeof(struct w1_netlink_msg) +
 			sizeof(struct w1_netlink_cmd) +
 			cmd->len, GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;

 	cm = (struct cn_msg *)(data);
 	h = (struct w1_netlink_msg *)(cm + 1);
 	c = (struct w1_netlink_cmd *)(h + 1);

 	memcpy(cm, msg, sizeof(struct cn_msg));
 	memcpy(h, hdr, sizeof(struct w1_netlink_msg));
 	memcpy(c, cmd, sizeof(struct w1_netlink_cmd));

 	cm->ack = msg->seq+1;
 	cm->len = sizeof(struct w1_netlink_msg) +
 		sizeof(struct w1_netlink_cmd) + cmd->len;

 	h->len = sizeof(struct w1_netlink_cmd) + cmd->len;

 	memcpy(c->data, cmd->data, c->len);

 	err = cn_netlink_send(cm, 0, GFP_KERNEL);

 	kfree(data);

 	return err;
 }

 static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg,
 		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
 {
 	int err = 0;

 	switch (cmd->cmd) {
 	case W1_CMD_TOUCH:
 		w1_touch_block(dev, cmd->data, cmd->len);
 		w1_send_read_reply(msg, hdr, cmd);
 		break;
 	case W1_CMD_READ:
 		w1_read_block(dev, cmd->data, cmd->len);
 		w1_send_read_reply(msg, hdr, cmd);
 		break;
 	case W1_CMD_WRITE:
 		w1_write_block(dev, cmd->data, cmd->len);
 		break;
 	default:
 		err = -EINVAL;
 		break;
 	}

 	return err;
 }

 static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg,
 		struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd)
 {
 	int err = -EINVAL;
 	struct cn_msg *msg;
 	struct w1_netlink_msg *hdr;
 	struct w1_netlink_cmd *cmd;

 	msg = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;

 	msg->id = req_msg->id;
 	msg->seq = req_msg->seq;
 	msg->ack = 0;
 	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);

 	hdr = (struct w1_netlink_msg *)(msg + 1);
 	cmd = (struct w1_netlink_cmd *)(hdr + 1);

 	hdr->type = W1_MASTER_CMD;
 	hdr->id = req_hdr->id;
 	hdr->len = sizeof(struct w1_netlink_cmd);

 	cmd->cmd = req_cmd->cmd;
 	cmd->len = 0;

 	switch (cmd->cmd) {
 	case W1_CMD_SEARCH:
 	case W1_CMD_ALARM_SEARCH:
 		err = w1_process_search_command(dev, msg,
 				PAGE_SIZE - msg->len - sizeof(struct cn_msg));
 		break;
 	case W1_CMD_READ:
 	case W1_CMD_WRITE:
 	case W1_CMD_TOUCH:
 		err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd);
 		break;
 	case W1_CMD_RESET:
 		err = w1_reset_bus(dev);
 		break;
 	default:
 		err = -EINVAL;
 		break;
 	}

 	kfree(msg);
 	return err;
 }

 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg,
 		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
 {
 	dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
 		__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
 		sl->reg_num.crc, cmd->cmd, cmd->len);

 	return w1_process_command_io(sl->master, msg, hdr, cmd);
 }

 static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd)
 {
 	struct w1_master *m;
 	struct cn_msg *cn;
 	struct w1_netlink_msg *w;
 	u32 *id;

 	if (mcmd->type != W1_LIST_MASTERS) {
 		printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n",
 			__func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len);
 		return -EPROTO;
 	}

 	cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!cn)
 		return -ENOMEM;

 	cn->id.idx = CN_W1_IDX;
 	cn->id.val = CN_W1_VAL;

 	cn->seq = msg->seq;
 	cn->ack = 1;
 	cn->len = sizeof(struct w1_netlink_msg);
 	w = (struct w1_netlink_msg *)(cn + 1);

 	w->type = W1_LIST_MASTERS;
 	w->status = 0;
 	w->len = 0;
 	id = (u32 *)(w + 1);

 	mutex_lock(&w1_mlock);
 	list_for_each_entry(m, &w1_masters, w1_master_entry) {
 		if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
 			cn_netlink_send(cn, 0, GFP_KERNEL);
 			cn->ack++;
 			cn->len = sizeof(struct w1_netlink_msg);
 			w->len = 0;
 			id = (u32 *)(w + 1);
 		}

 		*id = m->id;
 		w->len += sizeof(*id);
 		cn->len += sizeof(*id);
 		id++;
 	}
 	cn->ack = 0;
 	cn_netlink_send(cn, 0, GFP_KERNEL);
 	mutex_unlock(&w1_mlock);

 	kfree(cn);
 	return 0;
 }

 static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg,
 		struct w1_netlink_cmd *rcmd, int error)
 {
 	struct cn_msg *cmsg;
 	struct w1_netlink_msg *msg;
 	struct w1_netlink_cmd *cmd;

 	cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL);
 	if (!cmsg)
 		return -ENOMEM;

 	msg = (struct w1_netlink_msg *)(cmsg + 1);
 	cmd = (struct w1_netlink_cmd *)(msg + 1);

 	memcpy(cmsg, rcmsg, sizeof(*cmsg));
 	cmsg->len = sizeof(*msg);

 	memcpy(msg, rmsg, sizeof(*msg));
 	msg->len = 0;
 	msg->status = (short)-error;

 	if (rcmd) {
 		memcpy(cmd, rcmd, sizeof(*cmd));
 		cmd->len = 0;
 		msg->len += sizeof(*cmd);
 		cmsg->len += sizeof(*cmd);
 	}

 	error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
 	kfree(cmsg);

 	return error;
 }

 static void w1_cn_callback(struct cn_msg *msg)
 {
 	struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
 	struct w1_netlink_cmd *cmd;
 	struct w1_slave *sl;
 	struct w1_master *dev;
 	int err = 0;

 	while (msg->len && !err) {
 		struct w1_reg_num id;
 		u16 mlen = m->len;
 		u8 *cmd_data = m->data;

 		dev = NULL;
 		sl = NULL;
 		cmd = NULL;

 		memcpy(&id, m->id.id, sizeof(id));
 #if 0
 		printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
 				__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
 #endif
 		if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
 			err = -E2BIG;
 			break;
 		}

 		if (m->type == W1_MASTER_CMD) {
 			dev = w1_search_master_id(m->id.mst.id);
 		} else if (m->type == W1_SLAVE_CMD) {
 			sl = w1_search_slave(&id);
 			if (sl)
 				dev = sl->master;
 		} else {
 			err = w1_process_command_root(msg, m);
 			goto out_cont;
 		}

 		if (!dev) {
 			err = -ENODEV;
 			goto out_cont;
 		}

 		err = 0;
 		if (!mlen)
 			goto out_cont;

 		mutex_lock(&dev->mutex);

 		if (sl && w1_reset_select_slave(sl)) {
 			err = -ENODEV;
 			goto out_up;
 		}

 		while (mlen) {
 			cmd = (struct w1_netlink_cmd *)cmd_data;

 			if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
 				err = -E2BIG;
 				break;
 			}

 			if (sl)
 				err = w1_process_command_slave(sl, msg, m, cmd);
 			else
 				err = w1_process_command_master(dev, msg, m, cmd);

 			w1_netlink_send_error(msg, m, cmd, err);
 			err = 0;

 			cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
 			mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
 		}
 out_up:
 		atomic_dec(&dev->refcnt);
 		if (sl)
 			atomic_dec(&sl->refcnt);
 		mutex_unlock(&dev->mutex);
 out_cont:
 		if (!cmd || err)
 			w1_netlink_send_error(msg, m, cmd, err);
 		msg->len -= sizeof(struct w1_netlink_msg) + m->len;
 		m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);

 		/*
 		 * Let's allow requests for nonexisting devices.
 		 */
 		if (err == -ENODEV)
 			err = 0;
 	}
 }

 int w1_init_netlink(void)
 {
 	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};

 	return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
 }

 void w1_fini_netlink(void)
 {
 	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};

 	cn_del_callback(&w1_id);
 }
 #else
 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
 {
 }

 int w1_init_netlink(void)
 {
 	return 0;
 }

 void w1_fini_netlink(void)
 {
 }
 #endif
	/*
	* w1_netlink.c
	*
	* Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
	*
	*
	* 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/skbuff.h>
	#include <linux/netlink.h>
	#include <linux/connector.h>

	#include "w1.h"
	#include "w1_log.h"
	#include "w1_netlink.h"

	#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) \|\| (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
	void w1_netlink_send(struct w1_master dev, struct w1_netlink_msg msg)
	{
	char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
	struct cn_msg m = (struct cn_msg )buf;
	struct w1_netlink_msg w = (struct w1_netlink_msg )(m+1);

	memset(buf, 0, sizeof(buf));

	m->id.idx = CN_W1_IDX;
	m->id.val = CN_W1_VAL;

	m->seq = dev->seq++;
	m->len = sizeof(struct w1_netlink_msg);

	memcpy(w, msg, sizeof(struct w1_netlink_msg));

	cn_netlink_send(m, 0, GFP_KERNEL);
	}

	static void w1_send_slave(struct w1_master *dev, u64 rn)
	{
	struct cn_msg *msg = dev->priv;
	struct w1_netlink_msg hdr = (struct w1_netlink_msg )(msg + 1);
	struct w1_netlink_cmd cmd = (struct w1_netlink_cmd )(hdr + 1);
	int avail;

	avail = dev->priv_size - cmd->len;

	if (avail > 8) {
	u64 data = (void )(cmd + 1) + cmd->len;

	*data = rn;
	cmd->len += 8;
	hdr->len += 8;
	msg->len += 8;
	return;
	}

	msg->ack++;
	cn_netlink_send(msg, 0, GFP_KERNEL);

	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
	hdr->len = sizeof(struct w1_netlink_cmd);
	cmd->len = 0;
	}

	static int w1_process_search_command(struct w1_master dev, struct cn_msg msg,
	unsigned int avail)
	{
	struct w1_netlink_msg hdr = (struct w1_netlink_msg )(msg + 1);
	struct w1_netlink_cmd cmd = (struct w1_netlink_cmd )(hdr + 1);
	int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH;

	dev->priv = msg;
	dev->priv_size = avail;

	w1_search_devices(dev, search_type, w1_send_slave);

	msg->ack = 0;
	cn_netlink_send(msg, 0, GFP_KERNEL);

	dev->priv = NULL;
	dev->priv_size = 0;

	return 0;
	}

	static int w1_send_read_reply(struct cn_msg msg, struct w1_netlink_msg hdr,
	struct w1_netlink_cmd *cmd)
	{
	void *data;
	struct w1_netlink_msg *h;
	struct w1_netlink_cmd *c;
	struct cn_msg *cm;
	int err;

	data = kzalloc(sizeof(struct cn_msg) +
	sizeof(struct w1_netlink_msg) +
	sizeof(struct w1_netlink_cmd) +
	cmd->len, GFP_KERNEL);
	if (!data)
	return -ENOMEM;

	cm = (struct cn_msg *)(data);
	h = (struct w1_netlink_msg *)(cm + 1);
	c = (struct w1_netlink_cmd *)(h + 1);

	memcpy(cm, msg, sizeof(struct cn_msg));
	memcpy(h, hdr, sizeof(struct w1_netlink_msg));
	memcpy(c, cmd, sizeof(struct w1_netlink_cmd));

	cm->ack = msg->seq+1;
	cm->len = sizeof(struct w1_netlink_msg) +
	sizeof(struct w1_netlink_cmd) + cmd->len;

	h->len = sizeof(struct w1_netlink_cmd) + cmd->len;

	memcpy(c->data, cmd->data, c->len);

	err = cn_netlink_send(cm, 0, GFP_KERNEL);

	kfree(data);

	return err;
	}

	static int w1_process_command_io(struct w1_master dev, struct cn_msg msg,
	struct w1_netlink_msg hdr, struct w1_netlink_cmd cmd)
	{
	int err = 0;

	switch (cmd->cmd) {
	case W1_CMD_TOUCH:
	w1_touch_block(dev, cmd->data, cmd->len);
	w1_send_read_reply(msg, hdr, cmd);
	break;
	case W1_CMD_READ:
	w1_read_block(dev, cmd->data, cmd->len);
	w1_send_read_reply(msg, hdr, cmd);
	break;
	case W1_CMD_WRITE:
	w1_write_block(dev, cmd->data, cmd->len);
	break;
	default:
	err = -EINVAL;
	break;
	}

	return err;
	}

	static int w1_process_command_master(struct w1_master dev, struct cn_msg req_msg,
	struct w1_netlink_msg req_hdr, struct w1_netlink_cmd req_cmd)
	{
	int err = -EINVAL;
	struct cn_msg *msg;
	struct w1_netlink_msg *hdr;
	struct w1_netlink_cmd *cmd;

	msg = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!msg)
	return -ENOMEM;

	msg->id = req_msg->id;
	msg->seq = req_msg->seq;
	msg->ack = 0;
	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);

	hdr = (struct w1_netlink_msg *)(msg + 1);
	cmd = (struct w1_netlink_cmd *)(hdr + 1);

	hdr->type = W1_MASTER_CMD;
	hdr->id = req_hdr->id;
	hdr->len = sizeof(struct w1_netlink_cmd);

	cmd->cmd = req_cmd->cmd;
	cmd->len = 0;

	switch (cmd->cmd) {
	case W1_CMD_SEARCH:
	case W1_CMD_ALARM_SEARCH:
	err = w1_process_search_command(dev, msg,
	PAGE_SIZE - msg->len - sizeof(struct cn_msg));
	break;
	case W1_CMD_READ:
	case W1_CMD_WRITE:
	case W1_CMD_TOUCH:
	err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd);
	break;
	case W1_CMD_RESET:
	err = w1_reset_bus(dev);
	break;
	default:
	err = -EINVAL;
	break;
	}

	kfree(msg);
	return err;
	}

	static int w1_process_command_slave(struct w1_slave sl, struct cn_msg msg,
	struct w1_netlink_msg hdr, struct w1_netlink_cmd cmd)
	{
	dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
	__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
	sl->reg_num.crc, cmd->cmd, cmd->len);

	return w1_process_command_io(sl->master, msg, hdr, cmd);
	}

	static int w1_process_command_root(struct cn_msg msg, struct w1_netlink_msg mcmd)
	{
	struct w1_master *m;
	struct cn_msg *cn;
	struct w1_netlink_msg *w;
	u32 *id;

	if (mcmd->type != W1_LIST_MASTERS) {
	printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n",
	__func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len);
	return -EPROTO;
	}

	cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (!cn)
	return -ENOMEM;

	cn->id.idx = CN_W1_IDX;
	cn->id.val = CN_W1_VAL;

	cn->seq = msg->seq;
	cn->ack = 1;
	cn->len = sizeof(struct w1_netlink_msg);
	w = (struct w1_netlink_msg *)(cn + 1);

	w->type = W1_LIST_MASTERS;
	w->status = 0;
	w->len = 0;
	id = (u32 *)(w + 1);

	mutex_lock(&w1_mlock);
	list_for_each_entry(m, &w1_masters, w1_master_entry) {
	if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
	cn_netlink_send(cn, 0, GFP_KERNEL);
	cn->ack++;
	cn->len = sizeof(struct w1_netlink_msg);
	w->len = 0;
	id = (u32 *)(w + 1);
	}

	*id = m->id;
	w->len += sizeof(*id);
	cn->len += sizeof(*id);
	id++;
	}
	cn->ack = 0;
	cn_netlink_send(cn, 0, GFP_KERNEL);
	mutex_unlock(&w1_mlock);

	kfree(cn);
	return 0;
	}

	static int w1_netlink_send_error(struct cn_msg rcmsg, struct w1_netlink_msg rmsg,
	struct w1_netlink_cmd *rcmd, int error)
	{
	struct cn_msg *cmsg;
	struct w1_netlink_msg *msg;
	struct w1_netlink_cmd *cmd;

	cmsg = kzalloc(sizeof(msg) + sizeof(cmd) + sizeof(*cmsg), GFP_KERNEL);
	if (!cmsg)
	return -ENOMEM;

	msg = (struct w1_netlink_msg *)(cmsg + 1);
	cmd = (struct w1_netlink_cmd *)(msg + 1);

	memcpy(cmsg, rcmsg, sizeof(*cmsg));
	cmsg->len = sizeof(*msg);

	memcpy(msg, rmsg, sizeof(*msg));
	msg->len = 0;
	msg->status = (short)-error;

	if (rcmd) {
	memcpy(cmd, rcmd, sizeof(*cmd));
	cmd->len = 0;
	msg->len += sizeof(*cmd);
	cmsg->len += sizeof(*cmd);
	}

	error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
	kfree(cmsg);

	return error;
	}

	static void w1_cn_callback(struct cn_msg *msg)
	{
	struct w1_netlink_msg m = (struct w1_netlink_msg )(msg + 1);
	struct w1_netlink_cmd *cmd;
	struct w1_slave *sl;
	struct w1_master *dev;
	int err = 0;

	while (msg->len && !err) {
	struct w1_reg_num id;
	u16 mlen = m->len;
	u8 *cmd_data = m->data;

	dev = NULL;
	sl = NULL;
	cmd = NULL;

	memcpy(&id, m->id.id, sizeof(id));
	#if 0
	printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
	__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
	#endif
	if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
	err = -E2BIG;
	break;
	}

	if (m->type == W1_MASTER_CMD) {
	dev = w1_search_master_id(m->id.mst.id);
	} else if (m->type == W1_SLAVE_CMD) {
	sl = w1_search_slave(&id);
	if (sl)
	dev = sl->master;
	} else {
	err = w1_process_command_root(msg, m);
	goto out_cont;
	}

	if (!dev) {
	err = -ENODEV;
	goto out_cont;
	}

	err = 0;
	if (!mlen)
	goto out_cont;

	mutex_lock(&dev->mutex);

	if (sl && w1_reset_select_slave(sl)) {
	err = -ENODEV;
	goto out_up;
	}

	while (mlen) {
	cmd = (struct w1_netlink_cmd *)cmd_data;

	if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
	err = -E2BIG;
	break;
	}

	if (sl)
	err = w1_process_command_slave(sl, msg, m, cmd);
	else
	err = w1_process_command_master(dev, msg, m, cmd);

	w1_netlink_send_error(msg, m, cmd, err);
	err = 0;

	cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
	mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
	}
	out_up:
	atomic_dec(&dev->refcnt);
	if (sl)
	atomic_dec(&sl->refcnt);
	mutex_unlock(&dev->mutex);
	out_cont:
	if (!cmd \|\| err)
	w1_netlink_send_error(msg, m, cmd, err);
	msg->len -= sizeof(struct w1_netlink_msg) + m->len;
	m = (struct w1_netlink_msg )(((u8 )m) + sizeof(struct w1_netlink_msg) + m->len);

	/*
	* Let's allow requests for nonexisting devices.
	*/
	if (err == -ENODEV)
	err = 0;
	}
	}

	int w1_init_netlink(void)
	{
	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};

	return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
	}

	void w1_fini_netlink(void)
	{
	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};

	cn_del_callback(&w1_id);
	}
	#else
	void w1_netlink_send(struct w1_master dev, struct w1_netlink_msg msg)
	{
	}

	int w1_init_netlink(void)
	{
	return 0;
	}

	void w1_fini_netlink(void)
	{
	}
	#endif