[mirror_ubuntu-bionic-kernel.git] / drivers / w1 / w1_netlink.c

/*
 * 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 int w1_process_command_master(struct w1_master *dev, struct cn_msg *msg,
		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
{
	dev_dbg(&dev->dev, "%s: %s: cmd=%02x, len=%u.\n",
		__func__, dev->name, cmd->cmd, cmd->len);

	if (cmd->cmd != W1_CMD_SEARCH && cmd->cmd != W1_CMD_ALARM_SEARCH)
		return -EINVAL;

	w1_search_process(dev, (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
	return 0;
}

static int w1_send_read_reply(struct w1_slave *sl, 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_slave(struct w1_slave *sl, struct cn_msg *msg,
		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
{
	int err = 0;

	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);

	switch (cmd->cmd) {
		case W1_CMD_READ:
			w1_read_block(sl->master, cmd->data, cmd->len);
			w1_send_read_reply(sl, msg, hdr, cmd);
			break;
		case W1_CMD_WRITE:
			w1_write_block(sl->master, cmd->data, cmd->len);
			break;
		case W1_CMD_SEARCH:
		case W1_CMD_ALARM_SEARCH:
			w1_search_process(sl->master,
					(cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
			break;
		default:
			err = -1;
			break;
	}

	return err;
}

static void w1_cn_callback(void *data)
{
	struct cn_msg *msg = data;
	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;

		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 (!mlen)
			goto out_cont;

		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;
		}

		if (!dev) {
			err = -ENODEV;
			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)
				w1_process_command_slave(sl, msg, m, cmd);
			else
				w1_process_command_master(dev, msg, m, cmd);

			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:
		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;
	}
#if 0
	if (err) {
		printk("%s: malformed message. Dropping.\n", __func__);
	}
#endif
}

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
Commit	Line	Data
1da177e4 LT	1	/*
	2	* w1_netlink.c
	3	*
	4	* Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
	5	*
	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	#include <linux/skbuff.h>
	23	#include <linux/netlink.h>
12003375	24	#include <linux/connector.h>
1da177e4 LT	25
	26	#include "w1.h"
	27	#include "w1_log.h"
	28	#include "w1_netlink.h"
	29
46e07f6e	30	#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) \|\| (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
1da177e4 LT	31	void w1_netlink_send(struct w1_master dev, struct w1_netlink_msg msg)
1da177e4 LT	32	{
12003375 EP	33	char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
	34	struct cn_msg m = (struct cn_msg )buf;
	35	struct w1_netlink_msg w = (struct w1_netlink_msg )(m+1);
1da177e4	36
12003375	37	memset(buf, 0, sizeof(buf));
1da177e4	38
12003375 EP	39	m->id.idx = CN_W1_IDX;
12003375 EP	40	m->id.val = CN_W1_VAL;
1da177e4	41
12003375 EP	42	m->seq = dev->seq++;
12003375 EP	43	m->len = sizeof(struct w1_netlink_msg);
1da177e4	44
12003375	45	memcpy(w, msg, sizeof(struct w1_netlink_msg));
1da177e4	46
12003375 EP	47	cn_netlink_send(m, 0, GFP_KERNEL);
12003375 EP	48	}
1da177e4	49
12003375 EP	50	static int w1_process_command_master(struct w1_master dev, struct cn_msg msg,
	51	struct w1_netlink_msg hdr, struct w1_netlink_cmd cmd)
	52	{
	53	dev_dbg(&dev->dev, "%s: %s: cmd=%02x, len=%u.\n",
	54	__func__, dev->name, cmd->cmd, cmd->len);
1da177e4	55
12003375 EP	56	if (cmd->cmd != W1_CMD_SEARCH && cmd->cmd != W1_CMD_ALARM_SEARCH)
12003375 EP	57	return -EINVAL;
1da177e4	58
12003375 EP	59	w1_search_process(dev, (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
12003375 EP	60	return 0;
1da177e4	61	}
2d833179	62
12003375 EP	63	static int w1_send_read_reply(struct w1_slave sl, struct cn_msg msg,
12003375 EP	64	struct w1_netlink_msg hdr, struct w1_netlink_cmd cmd)
2d833179	65	{
12003375 EP	66	void *data;
	67	struct w1_netlink_msg *h;
	68	struct w1_netlink_cmd *c;
	69	struct cn_msg *cm;
	70	int err;
	71
	72	data = kzalloc(sizeof(struct cn_msg) +
	73	sizeof(struct w1_netlink_msg) +
	74	sizeof(struct w1_netlink_cmd) +
	75	cmd->len, GFP_KERNEL);
	76	if (!data)
	77	return -ENOMEM;
	78
	79	cm = (struct cn_msg *)(data);
	80	h = (struct w1_netlink_msg *)(cm + 1);
	81	c = (struct w1_netlink_cmd *)(h + 1);
	82
	83	memcpy(cm, msg, sizeof(struct cn_msg));
	84	memcpy(h, hdr, sizeof(struct w1_netlink_msg));
	85	memcpy(c, cmd, sizeof(struct w1_netlink_cmd));
	86
	87	cm->ack = msg->seq+1;
	88	cm->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd) + cmd->len;
	89
	90	h->len = sizeof(struct w1_netlink_cmd) + cmd->len;
	91
	92	memcpy(c->data, cmd->data, c->len);
	93
	94	err = cn_netlink_send(cm, 0, GFP_KERNEL);
	95
	96	kfree(data);
	97
	98	return err;
	99	}
	100
	101	static int w1_process_command_slave(struct w1_slave sl, struct cn_msg msg,
	102	struct w1_netlink_msg hdr, struct w1_netlink_cmd cmd)
	103	{
	104	int err = 0;
	105
	106	dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
	107	__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, sl->reg_num.crc,
	108	cmd->cmd, cmd->len);
	109
	110	switch (cmd->cmd) {
	111	case W1_CMD_READ:
	112	w1_read_block(sl->master, cmd->data, cmd->len);
	113	w1_send_read_reply(sl, msg, hdr, cmd);
	114	break;
	115	case W1_CMD_WRITE:
	116	w1_write_block(sl->master, cmd->data, cmd->len);
	117	break;
	118	case W1_CMD_SEARCH:
	119	case W1_CMD_ALARM_SEARCH:
	120	w1_search_process(sl->master,
	121	(cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH);
	122	break;
	123	default:
	124	err = -1;
	125	break;
2d833179 EP	126	}
2d833179 EP	127
12003375 EP	128	return err;
	129	}
	130
	131	static void w1_cn_callback(void *data)
	132	{
	133	struct cn_msg *msg = data;
	134	struct w1_netlink_msg m = (struct w1_netlink_msg )(msg + 1);
	135	struct w1_netlink_cmd *cmd;
	136	struct w1_slave *sl;
	137	struct w1_master *dev;
	138	int err = 0;
	139
	140	while (msg->len && !err) {
	141	struct w1_reg_num id;
	142	u16 mlen = m->len;
	143	u8 *cmd_data = m->data;
	144
	145	dev = NULL;
	146	sl = NULL;
	147
	148	memcpy(&id, m->id.id, sizeof(id));
	149	#if 0
	150	printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
	151	__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
	152	#endif
	153	if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
	154	err = -E2BIG;
	155	break;
	156	}
	157
	158	if (!mlen)
	159	goto out_cont;
	160
	161	if (m->type == W1_MASTER_CMD) {
	162	dev = w1_search_master_id(m->id.mst.id);
	163	} else if (m->type == W1_SLAVE_CMD) {
	164	sl = w1_search_slave(&id);
	165	if (sl)
	166	dev = sl->master;
	167	}
	168
	169	if (!dev) {
	170	err = -ENODEV;
	171	goto out_cont;
	172	}
	173
abd52a13	174	mutex_lock(&dev->mutex);
12003375 EP	175
	176	if (sl && w1_reset_select_slave(sl)) {
	177	err = -ENODEV;
	178	goto out_up;
	179	}
	180
	181	while (mlen) {
	182	cmd = (struct w1_netlink_cmd *)cmd_data;
	183
	184	if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
	185	err = -E2BIG;
	186	break;
	187	}
	188
	189	if (sl)
	190	w1_process_command_slave(sl, msg, m, cmd);
	191	else
	192	w1_process_command_master(dev, msg, m, cmd);
	193
	194	cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
	195	mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
	196	}
	197	out_up:
	198	atomic_dec(&dev->refcnt);
	199	if (sl)
	200	atomic_dec(&sl->refcnt);
abd52a13	201	mutex_unlock(&dev->mutex);
12003375 EP	202	out_cont:
	203	msg->len -= sizeof(struct w1_netlink_msg) + m->len;
	204	m = (struct w1_netlink_msg )(((u8 )m) + sizeof(struct w1_netlink_msg) + m->len);
	205
	206	/*
	207	* Let's allow requests for nonexisting devices.
	208	*/
	209	if (err == -ENODEV)
	210	err = 0;
	211	}
	212	#if 0
	213	if (err) {
	214	printk("%s: malformed message. Dropping.\n", __func__);
	215	}
	216	#endif
2d833179 EP	217	}
2d833179 EP	218
12003375	219	int w1_init_netlink(void)
2d833179	220	{
12003375 EP	221	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
	222
	223	return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
	224	}
	225
	226	void w1_fini_netlink(void)
	227	{
	228	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
	229
	230	cn_del_callback(&w1_id);
2d833179	231	}
1da177e4	232	#else
1da177e4 LT	233	void w1_netlink_send(struct w1_master dev, struct w1_netlink_msg msg)
	234	{
	235	}
2d833179	236
12003375	237	int w1_init_netlink(void)
2d833179 EP	238	{
	239	return 0;
	240	}
	241
12003375	242	void w1_fini_netlink(void)
2d833179 EP	243	{
2d833179 EP	244	}
1da177e4	245	#endif