Linux Audio

Check our new training course

Loading...
v3.1
  1/*
  2 * w1_netlink.c
  3 *
  4 * Copyright (c) 2003 Evgeniy Polyakov <zbr@ioremap.net>
  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/slab.h>
 23#include <linux/skbuff.h>
 24#include <linux/netlink.h>
 25#include <linux/connector.h>
 26
 27#include "w1.h"
 28#include "w1_log.h"
 29#include "w1_netlink.h"
 30
 31#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
 32void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
 33{
 34	char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
 35	struct cn_msg *m = (struct cn_msg *)buf;
 36	struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1);
 37
 38	memset(buf, 0, sizeof(buf));
 39
 40	m->id.idx = CN_W1_IDX;
 41	m->id.val = CN_W1_VAL;
 42
 43	m->seq = dev->seq++;
 44	m->len = sizeof(struct w1_netlink_msg);
 45
 46	memcpy(w, msg, sizeof(struct w1_netlink_msg));
 47
 48	cn_netlink_send(m, 0, GFP_KERNEL);
 49}
 50
 51static void w1_send_slave(struct w1_master *dev, u64 rn)
 52{
 53	struct cn_msg *msg = dev->priv;
 54	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 55	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 56	int avail;
 57
 58	/* update kernel slave list */
 59	w1_slave_found(dev, rn);
 60
 61	avail = dev->priv_size - cmd->len;
 62
 63	if (avail > 8) {
 64		u64 *data = (void *)(cmd + 1) + cmd->len;
 65
 66		*data = rn;
 67		cmd->len += 8;
 68		hdr->len += 8;
 69		msg->len += 8;
 70		return;
 71	}
 72
 73	msg->ack++;
 74	cn_netlink_send(msg, 0, GFP_KERNEL);
 75
 76	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
 77	hdr->len = sizeof(struct w1_netlink_cmd);
 78	cmd->len = 0;
 79}
 80
 81static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg,
 82		unsigned int avail)
 83{
 84	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 85	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 86	int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH;
 87
 88	dev->priv = msg;
 89	dev->priv_size = avail;
 90
 91	w1_search_process_cb(dev, search_type, w1_send_slave);
 92
 93	msg->ack = 0;
 94	cn_netlink_send(msg, 0, GFP_KERNEL);
 95
 96	dev->priv = NULL;
 97	dev->priv_size = 0;
 98
 99	return 0;
100}
101
102static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr,
103		struct w1_netlink_cmd *cmd)
104{
105	void *data;
106	struct w1_netlink_msg *h;
107	struct w1_netlink_cmd *c;
108	struct cn_msg *cm;
109	int err;
110
111	data = kzalloc(sizeof(struct cn_msg) +
112			sizeof(struct w1_netlink_msg) +
113			sizeof(struct w1_netlink_cmd) +
114			cmd->len, GFP_KERNEL);
115	if (!data)
116		return -ENOMEM;
117
118	cm = (struct cn_msg *)(data);
119	h = (struct w1_netlink_msg *)(cm + 1);
120	c = (struct w1_netlink_cmd *)(h + 1);
121
122	memcpy(cm, msg, sizeof(struct cn_msg));
123	memcpy(h, hdr, sizeof(struct w1_netlink_msg));
124	memcpy(c, cmd, sizeof(struct w1_netlink_cmd));
125
126	cm->ack = msg->seq+1;
127	cm->len = sizeof(struct w1_netlink_msg) +
128		sizeof(struct w1_netlink_cmd) + cmd->len;
129
130	h->len = sizeof(struct w1_netlink_cmd) + cmd->len;
131
132	memcpy(c->data, cmd->data, c->len);
133
134	err = cn_netlink_send(cm, 0, GFP_KERNEL);
135
136	kfree(data);
137
138	return err;
139}
140
141static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg,
142		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
143{
144	int err = 0;
145
146	switch (cmd->cmd) {
147	case W1_CMD_TOUCH:
148		w1_touch_block(dev, cmd->data, cmd->len);
149		w1_send_read_reply(msg, hdr, cmd);
150		break;
151	case W1_CMD_READ:
152		w1_read_block(dev, cmd->data, cmd->len);
153		w1_send_read_reply(msg, hdr, cmd);
154		break;
155	case W1_CMD_WRITE:
156		w1_write_block(dev, cmd->data, cmd->len);
157		break;
158	default:
159		err = -EINVAL;
160		break;
161	}
162
163	return err;
164}
165
166static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg,
167		struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd)
168{
169	int err = -EINVAL;
170	struct cn_msg *msg;
171	struct w1_netlink_msg *hdr;
172	struct w1_netlink_cmd *cmd;
173
174	msg = kzalloc(PAGE_SIZE, GFP_KERNEL);
175	if (!msg)
176		return -ENOMEM;
177
178	msg->id = req_msg->id;
179	msg->seq = req_msg->seq;
180	msg->ack = 0;
181	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
182
183	hdr = (struct w1_netlink_msg *)(msg + 1);
184	cmd = (struct w1_netlink_cmd *)(hdr + 1);
185
186	hdr->type = W1_MASTER_CMD;
187	hdr->id = req_hdr->id;
188	hdr->len = sizeof(struct w1_netlink_cmd);
189
190	cmd->cmd = req_cmd->cmd;
191	cmd->len = 0;
192
193	switch (cmd->cmd) {
194	case W1_CMD_SEARCH:
195	case W1_CMD_ALARM_SEARCH:
196		err = w1_process_search_command(dev, msg,
197				PAGE_SIZE - msg->len - sizeof(struct cn_msg));
198		break;
199	case W1_CMD_READ:
200	case W1_CMD_WRITE:
201	case W1_CMD_TOUCH:
202		err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd);
203		break;
204	case W1_CMD_RESET:
205		err = w1_reset_bus(dev);
206		break;
207	default:
208		err = -EINVAL;
209		break;
210	}
211
212	kfree(msg);
213	return err;
214}
215
216static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg,
217		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
218{
219	dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
220		__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
221		sl->reg_num.crc, cmd->cmd, cmd->len);
222
223	return w1_process_command_io(sl->master, msg, hdr, cmd);
224}
225
226static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd)
227{
228	struct w1_master *m;
229	struct cn_msg *cn;
230	struct w1_netlink_msg *w;
231	u32 *id;
232
233	if (mcmd->type != W1_LIST_MASTERS) {
234		printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n",
235			__func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len);
236		return -EPROTO;
237	}
238
239	cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
240	if (!cn)
241		return -ENOMEM;
242
243	cn->id.idx = CN_W1_IDX;
244	cn->id.val = CN_W1_VAL;
245
246	cn->seq = msg->seq;
247	cn->ack = 1;
248	cn->len = sizeof(struct w1_netlink_msg);
249	w = (struct w1_netlink_msg *)(cn + 1);
250
251	w->type = W1_LIST_MASTERS;
252	w->status = 0;
253	w->len = 0;
254	id = (u32 *)(w + 1);
255
256	mutex_lock(&w1_mlock);
257	list_for_each_entry(m, &w1_masters, w1_master_entry) {
258		if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
259			cn_netlink_send(cn, 0, GFP_KERNEL);
260			cn->ack++;
261			cn->len = sizeof(struct w1_netlink_msg);
262			w->len = 0;
263			id = (u32 *)(w + 1);
264		}
265
266		*id = m->id;
267		w->len += sizeof(*id);
268		cn->len += sizeof(*id);
269		id++;
270	}
271	cn->ack = 0;
272	cn_netlink_send(cn, 0, GFP_KERNEL);
273	mutex_unlock(&w1_mlock);
274
275	kfree(cn);
276	return 0;
277}
278
279static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg,
280		struct w1_netlink_cmd *rcmd, int error)
281{
282	struct cn_msg *cmsg;
283	struct w1_netlink_msg *msg;
284	struct w1_netlink_cmd *cmd;
285
286	cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL);
287	if (!cmsg)
288		return -ENOMEM;
289
290	msg = (struct w1_netlink_msg *)(cmsg + 1);
291	cmd = (struct w1_netlink_cmd *)(msg + 1);
292
293	memcpy(cmsg, rcmsg, sizeof(*cmsg));
294	cmsg->len = sizeof(*msg);
295
296	memcpy(msg, rmsg, sizeof(*msg));
297	msg->len = 0;
298	msg->status = (short)-error;
299
300	if (rcmd) {
301		memcpy(cmd, rcmd, sizeof(*cmd));
302		cmd->len = 0;
303		msg->len += sizeof(*cmd);
304		cmsg->len += sizeof(*cmd);
305	}
306
307	error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
308	kfree(cmsg);
309
310	return error;
311}
312
313static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
314{
315	struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
316	struct w1_netlink_cmd *cmd;
317	struct w1_slave *sl;
318	struct w1_master *dev;
319	int err = 0;
320
321	while (msg->len && !err) {
322		struct w1_reg_num id;
323		u16 mlen = m->len;
324		u8 *cmd_data = m->data;
325
326		dev = NULL;
327		sl = NULL;
328		cmd = NULL;
329
330		memcpy(&id, m->id.id, sizeof(id));
331#if 0
332		printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
333				__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
334#endif
335		if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
336			err = -E2BIG;
337			break;
338		}
339
340		if (m->type == W1_MASTER_CMD) {
341			dev = w1_search_master_id(m->id.mst.id);
342		} else if (m->type == W1_SLAVE_CMD) {
343			sl = w1_search_slave(&id);
344			if (sl)
345				dev = sl->master;
346		} else {
347			err = w1_process_command_root(msg, m);
348			goto out_cont;
349		}
350
351		if (!dev) {
352			err = -ENODEV;
353			goto out_cont;
354		}
355
356		err = 0;
357		if (!mlen)
358			goto out_cont;
359
360		mutex_lock(&dev->mutex);
361
362		if (sl && w1_reset_select_slave(sl)) {
363			err = -ENODEV;
364			goto out_up;
365		}
366
367		while (mlen) {
368			cmd = (struct w1_netlink_cmd *)cmd_data;
369
370			if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
371				err = -E2BIG;
372				break;
373			}
374
375			if (sl)
376				err = w1_process_command_slave(sl, msg, m, cmd);
377			else
378				err = w1_process_command_master(dev, msg, m, cmd);
379
380			w1_netlink_send_error(msg, m, cmd, err);
381			err = 0;
382
383			cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
384			mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
385		}
386out_up:
387		atomic_dec(&dev->refcnt);
388		if (sl)
389			atomic_dec(&sl->refcnt);
390		mutex_unlock(&dev->mutex);
391out_cont:
392		if (!cmd || err)
393			w1_netlink_send_error(msg, m, cmd, err);
394		msg->len -= sizeof(struct w1_netlink_msg) + m->len;
395		m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);
396
397		/*
398		 * Let's allow requests for nonexisting devices.
399		 */
400		if (err == -ENODEV)
401			err = 0;
402	}
403}
404
405int w1_init_netlink(void)
406{
407	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
408
409	return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
410}
411
412void w1_fini_netlink(void)
413{
414	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
415
416	cn_del_callback(&w1_id);
417}
418#else
419void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
420{
421}
422
423int w1_init_netlink(void)
424{
425	return 0;
426}
427
428void w1_fini_netlink(void)
429{
430}
431#endif
v3.5.6
  1/*
  2 * w1_netlink.c
  3 *
  4 * Copyright (c) 2003 Evgeniy Polyakov <zbr@ioremap.net>
  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/slab.h>
 23#include <linux/skbuff.h>
 24#include <linux/netlink.h>
 25#include <linux/connector.h>
 26
 27#include "w1.h"
 28#include "w1_log.h"
 29#include "w1_netlink.h"
 30
 31#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
 32void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
 33{
 34	char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
 35	struct cn_msg *m = (struct cn_msg *)buf;
 36	struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1);
 37
 38	memset(buf, 0, sizeof(buf));
 39
 40	m->id.idx = CN_W1_IDX;
 41	m->id.val = CN_W1_VAL;
 42
 43	m->seq = dev->seq++;
 44	m->len = sizeof(struct w1_netlink_msg);
 45
 46	memcpy(w, msg, sizeof(struct w1_netlink_msg));
 47
 48	cn_netlink_send(m, 0, GFP_KERNEL);
 49}
 50
 51static void w1_send_slave(struct w1_master *dev, u64 rn)
 52{
 53	struct cn_msg *msg = dev->priv;
 54	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 55	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 56	int avail;
 57
 58	/* update kernel slave list */
 59	w1_slave_found(dev, rn);
 60
 61	avail = dev->priv_size - cmd->len;
 62
 63	if (avail > 8) {
 64		u64 *data = (void *)(cmd + 1) + cmd->len;
 65
 66		*data = rn;
 67		cmd->len += 8;
 68		hdr->len += 8;
 69		msg->len += 8;
 70		return;
 71	}
 72
 73	msg->ack++;
 74	cn_netlink_send(msg, 0, GFP_KERNEL);
 75
 76	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
 77	hdr->len = sizeof(struct w1_netlink_cmd);
 78	cmd->len = 0;
 79}
 80
 81static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg,
 82		unsigned int avail)
 83{
 84	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 85	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 86	int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH;
 87
 88	dev->priv = msg;
 89	dev->priv_size = avail;
 90
 91	w1_search_process_cb(dev, search_type, w1_send_slave);
 92
 93	msg->ack = 0;
 94	cn_netlink_send(msg, 0, GFP_KERNEL);
 95
 96	dev->priv = NULL;
 97	dev->priv_size = 0;
 98
 99	return 0;
100}
101
102static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr,
103		struct w1_netlink_cmd *cmd)
104{
105	void *data;
106	struct w1_netlink_msg *h;
107	struct w1_netlink_cmd *c;
108	struct cn_msg *cm;
109	int err;
110
111	data = kzalloc(sizeof(struct cn_msg) +
112			sizeof(struct w1_netlink_msg) +
113			sizeof(struct w1_netlink_cmd) +
114			cmd->len, GFP_KERNEL);
115	if (!data)
116		return -ENOMEM;
117
118	cm = (struct cn_msg *)(data);
119	h = (struct w1_netlink_msg *)(cm + 1);
120	c = (struct w1_netlink_cmd *)(h + 1);
121
122	memcpy(cm, msg, sizeof(struct cn_msg));
123	memcpy(h, hdr, sizeof(struct w1_netlink_msg));
124	memcpy(c, cmd, sizeof(struct w1_netlink_cmd));
125
126	cm->ack = msg->seq+1;
127	cm->len = sizeof(struct w1_netlink_msg) +
128		sizeof(struct w1_netlink_cmd) + cmd->len;
129
130	h->len = sizeof(struct w1_netlink_cmd) + cmd->len;
131
132	memcpy(c->data, cmd->data, c->len);
133
134	err = cn_netlink_send(cm, 0, GFP_KERNEL);
135
136	kfree(data);
137
138	return err;
139}
140
141static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg,
142		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
143{
144	int err = 0;
145
146	switch (cmd->cmd) {
147	case W1_CMD_TOUCH:
148		w1_touch_block(dev, cmd->data, cmd->len);
149		w1_send_read_reply(msg, hdr, cmd);
150		break;
151	case W1_CMD_READ:
152		w1_read_block(dev, cmd->data, cmd->len);
153		w1_send_read_reply(msg, hdr, cmd);
154		break;
155	case W1_CMD_WRITE:
156		w1_write_block(dev, cmd->data, cmd->len);
157		break;
158	default:
159		err = -EINVAL;
160		break;
161	}
162
163	return err;
164}
165
166static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg,
167		struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd)
168{
169	int err = -EINVAL;
170	struct cn_msg *msg;
171	struct w1_netlink_msg *hdr;
172	struct w1_netlink_cmd *cmd;
173
174	msg = kzalloc(PAGE_SIZE, GFP_KERNEL);
175	if (!msg)
176		return -ENOMEM;
177
178	msg->id = req_msg->id;
179	msg->seq = req_msg->seq;
180	msg->ack = 0;
181	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
182
183	hdr = (struct w1_netlink_msg *)(msg + 1);
184	cmd = (struct w1_netlink_cmd *)(hdr + 1);
185
186	hdr->type = W1_MASTER_CMD;
187	hdr->id = req_hdr->id;
188	hdr->len = sizeof(struct w1_netlink_cmd);
189
190	cmd->cmd = req_cmd->cmd;
191	cmd->len = 0;
192
193	switch (cmd->cmd) {
194	case W1_CMD_SEARCH:
195	case W1_CMD_ALARM_SEARCH:
196		err = w1_process_search_command(dev, msg,
197				PAGE_SIZE - msg->len - sizeof(struct cn_msg));
198		break;
199	case W1_CMD_READ:
200	case W1_CMD_WRITE:
201	case W1_CMD_TOUCH:
202		err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd);
203		break;
204	case W1_CMD_RESET:
205		err = w1_reset_bus(dev);
206		break;
207	default:
208		err = -EINVAL;
209		break;
210	}
211
212	kfree(msg);
213	return err;
214}
215
216static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg,
217		struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
218{
219	dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
220		__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
221		sl->reg_num.crc, cmd->cmd, cmd->len);
222
223	return w1_process_command_io(sl->master, msg, hdr, cmd);
224}
225
226static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd)
227{
228	struct w1_master *m;
229	struct cn_msg *cn;
230	struct w1_netlink_msg *w;
231	u32 *id;
232
233	if (mcmd->type != W1_LIST_MASTERS) {
234		printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n",
235			__func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len);
236		return -EPROTO;
237	}
238
239	cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
240	if (!cn)
241		return -ENOMEM;
242
243	cn->id.idx = CN_W1_IDX;
244	cn->id.val = CN_W1_VAL;
245
246	cn->seq = msg->seq;
247	cn->ack = 1;
248	cn->len = sizeof(struct w1_netlink_msg);
249	w = (struct w1_netlink_msg *)(cn + 1);
250
251	w->type = W1_LIST_MASTERS;
252	w->status = 0;
253	w->len = 0;
254	id = (u32 *)(w + 1);
255
256	mutex_lock(&w1_mlock);
257	list_for_each_entry(m, &w1_masters, w1_master_entry) {
258		if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
259			cn_netlink_send(cn, 0, GFP_KERNEL);
260			cn->ack++;
261			cn->len = sizeof(struct w1_netlink_msg);
262			w->len = 0;
263			id = (u32 *)(w + 1);
264		}
265
266		*id = m->id;
267		w->len += sizeof(*id);
268		cn->len += sizeof(*id);
269		id++;
270	}
271	cn->ack = 0;
272	cn_netlink_send(cn, 0, GFP_KERNEL);
273	mutex_unlock(&w1_mlock);
274
275	kfree(cn);
276	return 0;
277}
278
279static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg,
280		struct w1_netlink_cmd *rcmd, int error)
281{
282	struct cn_msg *cmsg;
283	struct w1_netlink_msg *msg;
284	struct w1_netlink_cmd *cmd;
285
286	cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL);
287	if (!cmsg)
288		return -ENOMEM;
289
290	msg = (struct w1_netlink_msg *)(cmsg + 1);
291	cmd = (struct w1_netlink_cmd *)(msg + 1);
292
293	memcpy(cmsg, rcmsg, sizeof(*cmsg));
294	cmsg->len = sizeof(*msg);
295
296	memcpy(msg, rmsg, sizeof(*msg));
297	msg->len = 0;
298	msg->status = (short)-error;
299
300	if (rcmd) {
301		memcpy(cmd, rcmd, sizeof(*cmd));
302		cmd->len = 0;
303		msg->len += sizeof(*cmd);
304		cmsg->len += sizeof(*cmd);
305	}
306
307	error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
308	kfree(cmsg);
309
310	return error;
311}
312
313static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
314{
315	struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
316	struct w1_netlink_cmd *cmd;
317	struct w1_slave *sl;
318	struct w1_master *dev;
319	int err = 0;
320
321	while (msg->len && !err) {
322		struct w1_reg_num id;
323		u16 mlen = m->len;
324		u8 *cmd_data = m->data;
325
326		dev = NULL;
327		sl = NULL;
328		cmd = NULL;
329
330		memcpy(&id, m->id.id, sizeof(id));
331#if 0
332		printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
333				__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
334#endif
335		if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
336			err = -E2BIG;
337			break;
338		}
339
340		if (m->type == W1_MASTER_CMD) {
341			dev = w1_search_master_id(m->id.mst.id);
342		} else if (m->type == W1_SLAVE_CMD) {
343			sl = w1_search_slave(&id);
344			if (sl)
345				dev = sl->master;
346		} else {
347			err = w1_process_command_root(msg, m);
348			goto out_cont;
349		}
350
351		if (!dev) {
352			err = -ENODEV;
353			goto out_cont;
354		}
355
356		err = 0;
357		if (!mlen)
358			goto out_cont;
359
360		mutex_lock(&dev->mutex);
361
362		if (sl && w1_reset_select_slave(sl)) {
363			err = -ENODEV;
364			goto out_up;
365		}
366
367		while (mlen) {
368			cmd = (struct w1_netlink_cmd *)cmd_data;
369
370			if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
371				err = -E2BIG;
372				break;
373			}
374
375			if (sl)
376				err = w1_process_command_slave(sl, msg, m, cmd);
377			else
378				err = w1_process_command_master(dev, msg, m, cmd);
379
380			w1_netlink_send_error(msg, m, cmd, err);
381			err = 0;
382
383			cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
384			mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
385		}
386out_up:
387		atomic_dec(&dev->refcnt);
388		if (sl)
389			atomic_dec(&sl->refcnt);
390		mutex_unlock(&dev->mutex);
391out_cont:
392		if (!cmd || err)
393			w1_netlink_send_error(msg, m, cmd, err);
394		msg->len -= sizeof(struct w1_netlink_msg) + m->len;
395		m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);
396
397		/*
398		 * Let's allow requests for nonexisting devices.
399		 */
400		if (err == -ENODEV)
401			err = 0;
402	}
403}
404
405int w1_init_netlink(void)
406{
407	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
408
409	return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
410}
411
412void w1_fini_netlink(void)
413{
414	struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
415
416	cn_del_callback(&w1_id);
417}
418#else
419void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
420{
421}
422
423int w1_init_netlink(void)
424{
425	return 0;
426}
427
428void w1_fini_netlink(void)
429{
430}
431#endif