blob: dd96562372745ea11bd71d83901039423b24f403 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * w1_netlink.c
3 *
Evgeniy Polyakova8018762011-08-25 15:59:06 -07004 * Copyright (c) 2003 Evgeniy Polyakov <zbr@ioremap.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
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
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090022#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/skbuff.h>
24#include <linux/netlink.h>
Evgeniy Polyakov12003372006-03-23 19:11:58 +030025#include <linux/connector.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
27#include "w1.h"
28#include "w1_log.h"
29#include "w1_netlink.h"
30
Evgeniy Polyakov46e07f62006-04-03 12:01:12 +040031#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
David Fries8a0427d2014-04-08 22:37:09 -050032
33#define MIN(a, b) (((a) < (b)) ? (a) : (b))
34
35/* Bundle together everything required to process a request in one memory
36 * allocation.
37 */
38struct w1_cb_block {
39 atomic_t refcnt;
40 u32 portid; /* Sending process port ID */
41 /* maximum value for first_cn->len */
42 u16 maxlen;
43 /* pointers to building up the reply message */
44 struct cn_msg *first_cn; /* fixed once the structure is populated */
45 struct cn_msg *cn; /* advances as cn_msg is appeneded */
46 struct w1_netlink_msg *msg; /* advances as w1_netlink_msg is appened */
47 struct w1_netlink_cmd *cmd; /* advances as cmds are appened */
48 struct w1_netlink_msg *cur_msg; /* currently message being processed */
49 /* copy of the original request follows */
50 struct cn_msg request_cn;
51 /* followed by variable length:
52 * cn_msg, data (w1_netlink_msg and w1_netlink_cmd)
53 * one or more struct w1_cb_node
54 * reply first_cn, data (w1_netlink_msg and w1_netlink_cmd)
55 */
56};
57struct w1_cb_node {
58 struct w1_async_cmd async;
59 /* pointers within w1_cb_block and cn data */
60 struct w1_cb_block *block;
61 struct w1_netlink_msg *msg;
62 struct w1_slave *sl;
63 struct w1_master *dev;
64};
65
66/**
67 * w1_reply_len() - calculate current reply length, compare to maxlen
68 * @block: block to calculate
69 *
70 * Calculates the current message length including possible multiple
71 * cn_msg and data, excludes the first sizeof(struct cn_msg). Direclty
72 * compariable to maxlen and usable to send the message.
73 */
74static u16 w1_reply_len(struct w1_cb_block *block)
75{
76 if (!block->cn)
77 return 0;
78 return (u8 *)block->cn - (u8 *)block->first_cn + block->cn->len;
79}
80
81static void w1_unref_block(struct w1_cb_block *block)
82{
83 if (atomic_sub_return(1, &block->refcnt) == 0) {
84 u16 len = w1_reply_len(block);
85 if (len) {
86 cn_netlink_send_mult(block->first_cn, len,
87 block->portid, 0, GFP_KERNEL);
88 }
89 kfree(block);
90 }
91}
92
93/**
94 * w1_reply_make_space() - send message if needed to make space
95 * @block: block to make space on
96 * @space: how many bytes requested
97 *
98 * Verify there is enough room left for the caller to add "space" bytes to the
99 * message, if there isn't send the message and reset.
100 */
101static void w1_reply_make_space(struct w1_cb_block *block, u16 space)
102{
103 u16 len = w1_reply_len(block);
104 if (len + space >= block->maxlen) {
105 cn_netlink_send_mult(block->first_cn, len, block->portid, 0, GFP_KERNEL);
106 block->first_cn->len = 0;
107 block->cn = NULL;
108 block->msg = NULL;
109 block->cmd = NULL;
110 }
111}
112
113/* Early send when replies aren't bundled. */
114static void w1_netlink_check_send(struct w1_cb_block *block)
115{
116 if (!(block->request_cn.flags & W1_CN_BUNDLE) && block->cn)
117 w1_reply_make_space(block, block->maxlen);
118}
119
120/**
121 * w1_netlink_setup_msg() - prepare to write block->msg
122 * @block: block to operate on
123 * @ack: determines if cn can be reused
124 *
125 * block->cn will be setup with the correct ack, advancing if needed
126 * block->cn->len does not include space for block->msg
127 * block->msg advances but remains uninitialized
128 */
129static void w1_netlink_setup_msg(struct w1_cb_block *block, u32 ack)
130{
131 if (block->cn && block->cn->ack == ack) {
132 block->msg = (struct w1_netlink_msg *)(block->cn->data + block->cn->len);
133 } else {
134 /* advance or set to data */
135 if (block->cn)
136 block->cn = (struct cn_msg *)(block->cn->data +
137 block->cn->len);
138 else
139 block->cn = block->first_cn;
140
141 memcpy(block->cn, &block->request_cn, sizeof(*block->cn));
142 block->cn->len = 0;
143 block->cn->ack = ack;
144 block->msg = (struct w1_netlink_msg *)block->cn->data;
145 }
146}
147
148/* Append cmd to msg, include cmd->data as well. This is because
149 * any following data goes with the command and in the case of a read is
150 * the results.
151 */
152static void w1_netlink_queue_cmd(struct w1_cb_block *block,
153 struct w1_netlink_cmd *cmd)
154{
155 u32 space;
156 w1_reply_make_space(block, sizeof(struct cn_msg) +
157 sizeof(struct w1_netlink_msg) + sizeof(*cmd) + cmd->len);
158
159 /* There's a status message sent after each command, so no point
160 * in trying to bundle this cmd after an existing one, because
161 * there won't be one. Allocate and copy over a new cn_msg.
162 */
163 w1_netlink_setup_msg(block, block->request_cn.seq + 1);
164 memcpy(block->msg, block->cur_msg, sizeof(*block->msg));
165 block->cn->len += sizeof(*block->msg);
166 block->msg->len = 0;
167 block->cmd = (struct w1_netlink_cmd *)(block->msg->data);
168
169 space = sizeof(*cmd) + cmd->len;
170 if (block->cmd != cmd)
171 memcpy(block->cmd, cmd, space);
172 block->cn->len += space;
173 block->msg->len += space;
174}
175
176/* Append req_msg and req_cmd, no other commands and no data from req_cmd are
177 * copied.
178 */
179static void w1_netlink_queue_status(struct w1_cb_block *block,
180 struct w1_netlink_msg *req_msg, struct w1_netlink_cmd *req_cmd,
181 int error)
182{
183 u16 space = sizeof(struct cn_msg) + sizeof(*req_msg) + sizeof(*req_cmd);
184 w1_reply_make_space(block, space);
185 w1_netlink_setup_msg(block, block->request_cn.ack);
186
187 memcpy(block->msg, req_msg, sizeof(*req_msg));
188 block->cn->len += sizeof(*req_msg);
189 block->msg->len = 0;
190 block->msg->status = (u8)-error;
191 if (req_cmd) {
192 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)block->msg->data;
193 memcpy(cmd, req_cmd, sizeof(*cmd));
194 block->cn->len += sizeof(*cmd);
195 block->msg->len += sizeof(*cmd);
196 cmd->len = 0;
197 }
198 w1_netlink_check_send(block);
199}
200
201/**
202 * w1_netlink_send_error() - sends the error message now
203 * @cn: original cn_msg
204 * @msg: original w1_netlink_msg
205 * @portid: where to send it
206 * @error: error status
207 *
208 * Use when a block isn't available to queue the message to and cn, msg
209 * might not be contiguous.
210 */
211static void w1_netlink_send_error(struct cn_msg *cn, struct w1_netlink_msg *msg,
212 int portid, int error)
213{
214 struct {
215 struct cn_msg cn;
216 struct w1_netlink_msg msg;
217 } packet;
218 memcpy(&packet.cn, cn, sizeof(packet.cn));
219 memcpy(&packet.msg, msg, sizeof(packet.msg));
220 packet.cn.len = sizeof(packet.msg);
221 packet.msg.len = 0;
222 packet.msg.status = (u8)-error;
223 cn_netlink_send(&packet.cn, portid, 0, GFP_KERNEL);
224}
225
226/**
227 * w1_netlink_send() - sends w1 netlink notifications
228 * @dev: w1_master the even is associated with or for
229 * @msg: w1_netlink_msg message to be sent
230 *
231 * This are notifications generated from the kernel.
232 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
234{
David Fries8a0427d2014-04-08 22:37:09 -0500235 struct {
236 struct cn_msg cn;
237 struct w1_netlink_msg msg;
238 } packet;
239 memset(&packet, 0, sizeof(packet));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240
David Fries8a0427d2014-04-08 22:37:09 -0500241 packet.cn.id.idx = CN_W1_IDX;
242 packet.cn.id.val = CN_W1_VAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243
David Fries8a0427d2014-04-08 22:37:09 -0500244 packet.cn.seq = dev->seq++;
245 packet.cn.len = sizeof(*msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
David Fries8a0427d2014-04-08 22:37:09 -0500247 memcpy(&packet.msg, msg, sizeof(*msg));
248 packet.msg.len = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249
David Fries8a0427d2014-04-08 22:37:09 -0500250 cn_netlink_send(&packet.cn, 0, 0, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251}
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400252
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800253static void w1_send_slave(struct w1_master *dev, u64 rn)
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400254{
David Fries8a0427d2014-04-08 22:37:09 -0500255 struct w1_cb_block *block = dev->priv;
256 struct w1_netlink_cmd *cache_cmd = block->cmd;
David Fries6b355b32014-01-15 22:29:12 -0600257 u64 *data;
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400258
David Fries8a0427d2014-04-08 22:37:09 -0500259 w1_reply_make_space(block, sizeof(*data));
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300260
David Fries8a0427d2014-04-08 22:37:09 -0500261 /* Add cmd back if the packet was sent */
262 if (!block->cmd) {
263 cache_cmd->len = 0;
264 w1_netlink_queue_cmd(block, cache_cmd);
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800265 }
266
David Fries8a0427d2014-04-08 22:37:09 -0500267 data = (u64 *)(block->cmd->data + block->cmd->len);
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800268
David Fries6b355b32014-01-15 22:29:12 -0600269 *data = rn;
David Fries8a0427d2014-04-08 22:37:09 -0500270 block->cn->len += sizeof(*data);
271 block->msg->len += sizeof(*data);
272 block->cmd->len += sizeof(*data);
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800273}
274
David Fries70b34d22014-01-15 22:29:17 -0600275static void w1_found_send_slave(struct w1_master *dev, u64 rn)
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800276{
David Fries70b34d22014-01-15 22:29:17 -0600277 /* update kernel slave list */
278 w1_slave_found(dev, rn);
279
280 w1_send_slave(dev, rn);
281}
282
283/* Get the current slave list, or search (with or without alarm) */
David Fries8a0427d2014-04-08 22:37:09 -0500284static int w1_get_slaves(struct w1_master *dev, struct w1_netlink_cmd *req_cmd)
David Fries70b34d22014-01-15 22:29:17 -0600285{
David Fries70b34d22014-01-15 22:29:17 -0600286 struct w1_slave *sl;
287
David Fries8a0427d2014-04-08 22:37:09 -0500288 req_cmd->len = 0;
289 w1_netlink_queue_cmd(dev->priv, req_cmd);
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800290
David Fries70b34d22014-01-15 22:29:17 -0600291 if (req_cmd->cmd == W1_CMD_LIST_SLAVES) {
David Fries8a0427d2014-04-08 22:37:09 -0500292 u64 rn;
David Fries9fcbbac2014-01-15 22:29:18 -0600293 mutex_lock(&dev->list_mutex);
David Fries70b34d22014-01-15 22:29:17 -0600294 list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
295 memcpy(&rn, &sl->reg_num, sizeof(rn));
296 w1_send_slave(dev, rn);
297 }
David Fries9fcbbac2014-01-15 22:29:18 -0600298 mutex_unlock(&dev->list_mutex);
David Fries70b34d22014-01-15 22:29:17 -0600299 } else {
David Fries8a0427d2014-04-08 22:37:09 -0500300 w1_search_process_cb(dev, req_cmd->cmd == W1_CMD_ALARM_SEARCH ?
David Fries70b34d22014-01-15 22:29:17 -0600301 W1_ALARM_SEARCH : W1_SEARCH, w1_found_send_slave);
302 }
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800303
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400304 return 0;
305}
306
David Fries8a0427d2014-04-08 22:37:09 -0500307static int w1_process_command_io(struct w1_master *dev,
308 struct w1_netlink_cmd *cmd)
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800309{
310 int err = 0;
311
312 switch (cmd->cmd) {
313 case W1_CMD_TOUCH:
314 w1_touch_block(dev, cmd->data, cmd->len);
David Fries8a0427d2014-04-08 22:37:09 -0500315 w1_netlink_queue_cmd(dev->priv, cmd);
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800316 break;
317 case W1_CMD_READ:
318 w1_read_block(dev, cmd->data, cmd->len);
David Fries8a0427d2014-04-08 22:37:09 -0500319 w1_netlink_queue_cmd(dev->priv, cmd);
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800320 break;
321 case W1_CMD_WRITE:
322 w1_write_block(dev, cmd->data, cmd->len);
323 break;
324 default:
Evgeniy Polyakov40370142009-01-07 18:09:05 -0800325 err = -EINVAL;
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800326 break;
327 }
328
329 return err;
330}
331
David Fries70b34d22014-01-15 22:29:17 -0600332static int w1_process_command_addremove(struct w1_master *dev,
David Fries70b34d22014-01-15 22:29:17 -0600333 struct w1_netlink_cmd *cmd)
334{
335 struct w1_slave *sl;
336 int err = 0;
337 struct w1_reg_num *id;
338
David Fries8a0427d2014-04-08 22:37:09 -0500339 if (cmd->len != sizeof(*id))
David Fries70b34d22014-01-15 22:29:17 -0600340 return -EINVAL;
341
342 id = (struct w1_reg_num *)cmd->data;
343
344 sl = w1_slave_search_device(dev, id);
345 switch (cmd->cmd) {
346 case W1_CMD_SLAVE_ADD:
347 if (sl)
348 err = -EINVAL;
349 else
350 err = w1_attach_slave_device(dev, id);
351 break;
352 case W1_CMD_SLAVE_REMOVE:
353 if (sl)
354 w1_slave_detach(sl);
355 else
356 err = -EINVAL;
357 break;
358 default:
359 err = -EINVAL;
360 break;
361 }
362
363 return err;
364}
365
366static int w1_process_command_master(struct w1_master *dev,
David Fries70b34d22014-01-15 22:29:17 -0600367 struct w1_netlink_cmd *req_cmd)
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800368{
369 int err = -EINVAL;
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800370
David Friesd3a8a9d2014-01-15 22:29:26 -0600371 /* drop bus_mutex for search (does it's own locking), and add/remove
372 * which doesn't use the bus
373 */
David Fries70b34d22014-01-15 22:29:17 -0600374 switch (req_cmd->cmd) {
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800375 case W1_CMD_SEARCH:
376 case W1_CMD_ALARM_SEARCH:
David Fries70b34d22014-01-15 22:29:17 -0600377 case W1_CMD_LIST_SLAVES:
David Friesd3a8a9d2014-01-15 22:29:26 -0600378 mutex_unlock(&dev->bus_mutex);
David Fries8a0427d2014-04-08 22:37:09 -0500379 err = w1_get_slaves(dev, req_cmd);
David Friesd3a8a9d2014-01-15 22:29:26 -0600380 mutex_lock(&dev->bus_mutex);
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800381 break;
382 case W1_CMD_READ:
383 case W1_CMD_WRITE:
384 case W1_CMD_TOUCH:
David Fries8a0427d2014-04-08 22:37:09 -0500385 err = w1_process_command_io(dev, req_cmd);
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800386 break;
Evgeniy Polyakovf89735c2009-01-07 18:09:04 -0800387 case W1_CMD_RESET:
388 err = w1_reset_bus(dev);
389 break;
David Fries70b34d22014-01-15 22:29:17 -0600390 case W1_CMD_SLAVE_ADD:
391 case W1_CMD_SLAVE_REMOVE:
David Friesd3a8a9d2014-01-15 22:29:26 -0600392 mutex_unlock(&dev->bus_mutex);
393 mutex_lock(&dev->mutex);
David Fries8a0427d2014-04-08 22:37:09 -0500394 err = w1_process_command_addremove(dev, req_cmd);
David Friesd3a8a9d2014-01-15 22:29:26 -0600395 mutex_unlock(&dev->mutex);
396 mutex_lock(&dev->bus_mutex);
David Fries70b34d22014-01-15 22:29:17 -0600397 break;
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800398 default:
Evgeniy Polyakov40370142009-01-07 18:09:05 -0800399 err = -EINVAL;
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800400 break;
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800401 }
402
Evgeniy Polyakov3b838402009-01-07 18:09:01 -0800403 return err;
404}
405
David Fries8a0427d2014-04-08 22:37:09 -0500406static int w1_process_command_slave(struct w1_slave *sl,
407 struct w1_netlink_cmd *cmd)
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300408{
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300409 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
Evgeniy Polyakovc7e26632009-01-07 18:09:03 -0800410 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
411 sl->reg_num.crc, cmd->cmd, cmd->len);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300412
David Fries8a0427d2014-04-08 22:37:09 -0500413 return w1_process_command_io(sl->master, cmd);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300414}
415
David Fries8a0427d2014-04-08 22:37:09 -0500416static int w1_process_command_root(struct cn_msg *req_cn, u32 portid)
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800417{
David Fries8a0427d2014-04-08 22:37:09 -0500418 struct w1_master *dev;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800419 struct cn_msg *cn;
David Fries8a0427d2014-04-08 22:37:09 -0500420 struct w1_netlink_msg *msg;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800421 u32 *id;
422
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800423 cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
424 if (!cn)
425 return -ENOMEM;
426
427 cn->id.idx = CN_W1_IDX;
428 cn->id.val = CN_W1_VAL;
429
David Fries8a0427d2014-04-08 22:37:09 -0500430 cn->seq = req_cn->seq;
431 cn->ack = req_cn->seq + 1;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800432 cn->len = sizeof(struct w1_netlink_msg);
David Fries8a0427d2014-04-08 22:37:09 -0500433 msg = (struct w1_netlink_msg *)cn->data;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800434
David Fries8a0427d2014-04-08 22:37:09 -0500435 msg->type = W1_LIST_MASTERS;
436 msg->status = 0;
437 msg->len = 0;
438 id = (u32 *)msg->data;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800439
440 mutex_lock(&w1_mlock);
David Fries8a0427d2014-04-08 22:37:09 -0500441 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800442 if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
David Fries5dbf5672014-01-15 22:29:20 -0600443 cn_netlink_send(cn, portid, 0, GFP_KERNEL);
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800444 cn->len = sizeof(struct w1_netlink_msg);
David Fries8a0427d2014-04-08 22:37:09 -0500445 msg->len = 0;
446 id = (u32 *)msg->data;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800447 }
448
David Fries8a0427d2014-04-08 22:37:09 -0500449 *id = dev->id;
450 msg->len += sizeof(*id);
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800451 cn->len += sizeof(*id);
452 id++;
453 }
David Fries5dbf5672014-01-15 22:29:20 -0600454 cn_netlink_send(cn, portid, 0, GFP_KERNEL);
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800455 mutex_unlock(&w1_mlock);
456
457 kfree(cn);
458 return 0;
459}
460
David Fries9fcbbac2014-01-15 22:29:18 -0600461static void w1_process_cb(struct w1_master *dev, struct w1_async_cmd *async_cmd)
462{
463 struct w1_cb_node *node = container_of(async_cmd, struct w1_cb_node,
464 async);
David Fries8a0427d2014-04-08 22:37:09 -0500465 u16 mlen = node->msg->len;
466 u16 len;
David Fries9fcbbac2014-01-15 22:29:18 -0600467 int err = 0;
468 struct w1_slave *sl = node->sl;
David Fries8a0427d2014-04-08 22:37:09 -0500469 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)node->msg->data;
David Fries9fcbbac2014-01-15 22:29:18 -0600470
David Friesd3a8a9d2014-01-15 22:29:26 -0600471 mutex_lock(&dev->bus_mutex);
David Fries8a0427d2014-04-08 22:37:09 -0500472 dev->priv = node->block;
David Fries9fcbbac2014-01-15 22:29:18 -0600473 if (sl && w1_reset_select_slave(sl))
474 err = -ENODEV;
David Fries8a0427d2014-04-08 22:37:09 -0500475 node->block->cur_msg = node->msg;
David Fries9fcbbac2014-01-15 22:29:18 -0600476
477 while (mlen && !err) {
David Fries9fcbbac2014-01-15 22:29:18 -0600478 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
479 err = -E2BIG;
480 break;
481 }
482
483 if (sl)
David Fries8a0427d2014-04-08 22:37:09 -0500484 err = w1_process_command_slave(sl, cmd);
David Fries9fcbbac2014-01-15 22:29:18 -0600485 else
David Fries8a0427d2014-04-08 22:37:09 -0500486 err = w1_process_command_master(dev, cmd);
487 w1_netlink_check_send(node->block);
David Fries9fcbbac2014-01-15 22:29:18 -0600488
David Fries8a0427d2014-04-08 22:37:09 -0500489 w1_netlink_queue_status(node->block, node->msg, cmd, err);
David Fries9fcbbac2014-01-15 22:29:18 -0600490 err = 0;
491
David Fries8a0427d2014-04-08 22:37:09 -0500492 len = sizeof(*cmd) + cmd->len;
493 cmd = (struct w1_netlink_cmd *)((u8 *)cmd + len);
494 mlen -= len;
David Fries9fcbbac2014-01-15 22:29:18 -0600495 }
496
497 if (!cmd || err)
David Fries8a0427d2014-04-08 22:37:09 -0500498 w1_netlink_queue_status(node->block, node->msg, cmd, err);
David Fries9fcbbac2014-01-15 22:29:18 -0600499
David Fries593ceb02014-04-08 22:37:07 -0500500 /* ref taken in w1_search_slave or w1_search_master_id when building
501 * the block
502 */
David Fries9fcbbac2014-01-15 22:29:18 -0600503 if (sl)
504 w1_unref_slave(sl);
505 else
506 atomic_dec(&dev->refcnt);
David Fries8a0427d2014-04-08 22:37:09 -0500507 dev->priv = NULL;
David Friesd3a8a9d2014-01-15 22:29:26 -0600508 mutex_unlock(&dev->bus_mutex);
David Fries9fcbbac2014-01-15 22:29:18 -0600509
510 mutex_lock(&dev->list_mutex);
511 list_del(&async_cmd->async_entry);
512 mutex_unlock(&dev->list_mutex);
513
David Fries8a0427d2014-04-08 22:37:09 -0500514 w1_unref_block(node->block);
David Fries9fcbbac2014-01-15 22:29:18 -0600515}
516
David Fries8a0427d2014-04-08 22:37:09 -0500517static void w1_list_count_cmds(struct w1_netlink_msg *msg, int *cmd_count,
518 u16 *slave_len)
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300519{
David Fries8a0427d2014-04-08 22:37:09 -0500520 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)msg->data;
521 u16 mlen = msg->len;
522 u16 len;
523 int slave_list = 0;
524 while (mlen) {
525 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen)
526 break;
527
528 switch (cmd->cmd) {
529 case W1_CMD_SEARCH:
530 case W1_CMD_ALARM_SEARCH:
531 case W1_CMD_LIST_SLAVES:
532 ++slave_list;
533 }
534 ++*cmd_count;
535 len = sizeof(*cmd) + cmd->len;
536 cmd = (struct w1_netlink_cmd *)((u8 *)cmd + len);
537 mlen -= len;
538 }
539
540 if (slave_list) {
541 struct w1_master *dev = w1_search_master_id(msg->id.mst.id);
542 if (dev) {
543 /* Bytes, and likely an overstimate, and if it isn't
544 * the results can still be split between packets.
545 */
546 *slave_len += sizeof(struct w1_reg_num) * slave_list *
547 (dev->slave_count + dev->max_slave_count);
548 /* search incremented it */
549 atomic_dec(&dev->refcnt);
550 }
551 }
552}
553
554static void w1_cn_callback(struct cn_msg *cn, struct netlink_skb_parms *nsp)
555{
556 struct w1_netlink_msg *msg = (struct w1_netlink_msg *)(cn + 1);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300557 struct w1_slave *sl;
558 struct w1_master *dev;
David Fries9fcbbac2014-01-15 22:29:18 -0600559 u16 msg_len;
David Fries8a0427d2014-04-08 22:37:09 -0500560 u16 slave_len = 0;
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300561 int err = 0;
David Fries9fcbbac2014-01-15 22:29:18 -0600562 struct w1_cb_block *block = NULL;
563 struct w1_cb_node *node = NULL;
564 int node_count = 0;
David Fries8a0427d2014-04-08 22:37:09 -0500565 int cmd_count = 0;
566
567 /* If any unknown flag is set let the application know, that way
568 * applications can detect the absence of features in kernels that
569 * don't know about them. http://lwn.net/Articles/587527/
570 */
571 if (cn->flags & ~(W1_CN_BUNDLE)) {
572 w1_netlink_send_error(cn, msg, nsp->portid, -EINVAL);
573 return;
574 }
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300575
David Fries9fcbbac2014-01-15 22:29:18 -0600576 /* Count the number of master or slave commands there are to allocate
577 * space for one cb_node each.
578 */
David Fries8a0427d2014-04-08 22:37:09 -0500579 msg_len = cn->len;
David Fries9fcbbac2014-01-15 22:29:18 -0600580 while (msg_len && !err) {
David Fries8a0427d2014-04-08 22:37:09 -0500581 if (msg->len + sizeof(struct w1_netlink_msg) > msg_len) {
David Fries9fcbbac2014-01-15 22:29:18 -0600582 err = -E2BIG;
583 break;
584 }
585
David Fries8a0427d2014-04-08 22:37:09 -0500586 /* count messages for nodes and allocate any additional space
587 * required for slave lists
588 */
589 if (msg->type == W1_MASTER_CMD || msg->type == W1_SLAVE_CMD) {
David Fries9fcbbac2014-01-15 22:29:18 -0600590 ++node_count;
David Fries8a0427d2014-04-08 22:37:09 -0500591 w1_list_count_cmds(msg, &cmd_count, &slave_len);
592 }
David Fries9fcbbac2014-01-15 22:29:18 -0600593
David Fries8a0427d2014-04-08 22:37:09 -0500594 msg_len -= sizeof(struct w1_netlink_msg) + msg->len;
595 msg = (struct w1_netlink_msg *)(((u8 *)msg) +
596 sizeof(struct w1_netlink_msg) + msg->len);
David Fries9fcbbac2014-01-15 22:29:18 -0600597 }
David Fries8a0427d2014-04-08 22:37:09 -0500598 msg = (struct w1_netlink_msg *)(cn + 1);
David Fries9fcbbac2014-01-15 22:29:18 -0600599 if (node_count) {
David Fries8a0427d2014-04-08 22:37:09 -0500600 int size;
601 u16 reply_size = sizeof(*cn) + cn->len + slave_len;
602 if (cn->flags & W1_CN_BUNDLE) {
603 /* bundling duplicats some of the messages */
604 reply_size += 2 * cmd_count * (sizeof(struct cn_msg) +
605 sizeof(struct w1_netlink_msg) +
606 sizeof(struct w1_netlink_cmd));
607 }
608 reply_size = MIN(CONNECTOR_MAX_MSG_SIZE, reply_size);
609
610 /* allocate space for the block, a copy of the original message,
611 * one node per cmd to point into the original message,
612 * space for replies which is the original message size plus
613 * space for any list slave data and status messages
614 * cn->len doesn't include itself which is part of the block
615 * */
616 size = /* block + original message */
617 sizeof(struct w1_cb_block) + sizeof(*cn) + cn->len +
618 /* space for nodes */
619 node_count * sizeof(struct w1_cb_node) +
620 /* replies */
621 sizeof(struct cn_msg) + reply_size;
622 block = kzalloc(size, GFP_KERNEL);
David Fries9fcbbac2014-01-15 22:29:18 -0600623 if (!block) {
David Fries8a0427d2014-04-08 22:37:09 -0500624 /* if the system is already out of memory,
625 * (A) will this work, and (B) would it be better
626 * to not try?
627 */
628 w1_netlink_send_error(cn, msg, nsp->portid, -ENOMEM);
David Fries9fcbbac2014-01-15 22:29:18 -0600629 return;
630 }
631 atomic_set(&block->refcnt, 1);
David Fries5dbf5672014-01-15 22:29:20 -0600632 block->portid = nsp->portid;
David Fries8a0427d2014-04-08 22:37:09 -0500633 memcpy(&block->request_cn, cn, sizeof(*cn) + cn->len);
634 node = (struct w1_cb_node *)(block->request_cn.data + cn->len);
635
636 /* Sneeky, when not bundling, reply_size is the allocated space
637 * required for the reply, cn_msg isn't part of maxlen so
638 * it should be reply_size - sizeof(struct cn_msg), however
639 * when checking if there is enough space, w1_reply_make_space
640 * is called with the full message size including cn_msg,
641 * because it isn't known at that time if an additional cn_msg
642 * will need to be allocated. So an extra cn_msg is added
643 * above in "size".
644 */
645 block->maxlen = reply_size;
646 block->first_cn = (struct cn_msg *)(node + node_count);
647 memset(block->first_cn, 0, sizeof(*block->first_cn));
David Fries9fcbbac2014-01-15 22:29:18 -0600648 }
649
David Fries8a0427d2014-04-08 22:37:09 -0500650 msg_len = cn->len;
David Fries9fcbbac2014-01-15 22:29:18 -0600651 while (msg_len && !err) {
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300652
653 dev = NULL;
654 sl = NULL;
655
David Fries8a0427d2014-04-08 22:37:09 -0500656 if (msg->len + sizeof(struct w1_netlink_msg) > msg_len) {
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300657 err = -E2BIG;
658 break;
659 }
660
David Fries593ceb02014-04-08 22:37:07 -0500661 /* execute on this thread, no need to process later */
David Fries8a0427d2014-04-08 22:37:09 -0500662 if (msg->type == W1_LIST_MASTERS) {
663 err = w1_process_command_root(cn, nsp->portid);
David Fries593ceb02014-04-08 22:37:07 -0500664 goto out_cont;
665 }
666
667 /* All following message types require additional data,
668 * check here before references are taken.
669 */
David Fries8a0427d2014-04-08 22:37:09 -0500670 if (!msg->len) {
David Fries593ceb02014-04-08 22:37:07 -0500671 err = -EPROTO;
672 goto out_cont;
673 }
674
David Fries8a0427d2014-04-08 22:37:09 -0500675 /* both search calls take references */
676 if (msg->type == W1_MASTER_CMD) {
677 dev = w1_search_master_id(msg->id.mst.id);
678 } else if (msg->type == W1_SLAVE_CMD) {
679 sl = w1_search_slave((struct w1_reg_num *)msg->id.id);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300680 if (sl)
681 dev = sl->master;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800682 } else {
Fjodor Schelichowfdc91672014-06-19 02:52:00 +0200683 pr_notice("%s: cn: %x.%x, wrong type: %u, len: %u.\n",
David Fries8a0427d2014-04-08 22:37:09 -0500684 __func__, cn->id.idx, cn->id.val,
685 msg->type, msg->len);
David Fries593ceb02014-04-08 22:37:07 -0500686 err = -EPROTO;
Evgeniy Polyakov610705e2009-01-07 18:08:59 -0800687 goto out_cont;
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300688 }
689
690 if (!dev) {
691 err = -ENODEV;
692 goto out_cont;
693 }
694
Evgeniy Polyakov9be62e02009-01-07 18:09:01 -0800695 err = 0;
Evgeniy Polyakov9be62e02009-01-07 18:09:01 -0800696
David Fries9fcbbac2014-01-15 22:29:18 -0600697 atomic_inc(&block->refcnt);
698 node->async.cb = w1_process_cb;
699 node->block = block;
David Fries8a0427d2014-04-08 22:37:09 -0500700 node->msg = (struct w1_netlink_msg *)((u8 *)&block->request_cn +
701 (size_t)((u8 *)msg - (u8 *)cn));
David Fries9fcbbac2014-01-15 22:29:18 -0600702 node->sl = sl;
703 node->dev = dev;
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300704
David Fries9fcbbac2014-01-15 22:29:18 -0600705 mutex_lock(&dev->list_mutex);
706 list_add_tail(&node->async.async_entry, &dev->async_list);
707 wake_up_process(dev->thread);
708 mutex_unlock(&dev->list_mutex);
709 ++node;
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300710
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300711out_cont:
David Fries8a0427d2014-04-08 22:37:09 -0500712 /* Can't queue because that modifies block and another
713 * thread could be processing the messages by now and
714 * there isn't a lock, send directly.
715 */
David Fries9fcbbac2014-01-15 22:29:18 -0600716 if (err)
David Fries8a0427d2014-04-08 22:37:09 -0500717 w1_netlink_send_error(cn, msg, nsp->portid, err);
718 msg_len -= sizeof(struct w1_netlink_msg) + msg->len;
719 msg = (struct w1_netlink_msg *)(((u8 *)msg) +
720 sizeof(struct w1_netlink_msg) + msg->len);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300721
722 /*
723 * Let's allow requests for nonexisting devices.
724 */
725 if (err == -ENODEV)
726 err = 0;
727 }
David Fries8a0427d2014-04-08 22:37:09 -0500728 if (block)
729 w1_unref_block(block);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300730}
731
732int w1_init_netlink(void)
733{
734 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
735
736 return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
737}
738
739void w1_fini_netlink(void)
740{
741 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
742
743 cn_del_callback(&w1_id);
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400744}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745#else
David Fries8a0427d2014-04-08 22:37:09 -0500746void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *cn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747{
748}
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400749
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300750int w1_init_netlink(void)
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400751{
752 return 0;
753}
754
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300755void w1_fini_netlink(void)
Evgeniy Polyakov2d833172005-07-27 13:10:11 +0400756{
757}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758#endif