diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-07 18:37:24 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-07 18:37:24 -0500 |
commit | 7c7758f99d39d529a64d4f60d22129bbf2f16d74 (patch) | |
tree | 8847b5e56812fe4c4c812cfffc78e391a91f4ebe /net/wimax/op-msg.c | |
parent | 67acd8b4b7a3f1b183ae358e1dfdb8a80e170736 (diff) | |
parent | 8a70da82edc50aa7a4b54864babf2d72538ba1bb (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (123 commits)
wimax/i2400m: add CREDITS and MAINTAINERS entries
wimax: export linux/wimax.h and linux/wimax/i2400m.h with headers_install
i2400m: Makefile and Kconfig
i2400m/SDIO: TX and RX path backends
i2400m/SDIO: firmware upload backend
i2400m/SDIO: probe/disconnect, dev init/shutdown and reset backends
i2400m/SDIO: header for the SDIO subdriver
i2400m/USB: TX and RX path backends
i2400m/USB: firmware upload backend
i2400m/USB: probe/disconnect, dev init/shutdown and reset backends
i2400m/USB: header for the USB bus driver
i2400m: debugfs controls
i2400m: various functions for device management
i2400m: RX and TX data/control paths
i2400m: firmware loading and bootrom initialization
i2400m: linkage to the networking stack
i2400m: Generic probe/disconnect, reset and message passing
i2400m: host/device procotol and core driver definitions
i2400m: documentation and instructions for usage
wimax: Makefile, Kconfig and docbook linkage for the stack
...
Diffstat (limited to 'net/wimax/op-msg.c')
-rw-r--r-- | net/wimax/op-msg.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/net/wimax/op-msg.c b/net/wimax/op-msg.c new file mode 100644 index 000000000000..cb3b4ad53683 --- /dev/null +++ b/net/wimax/op-msg.c | |||
@@ -0,0 +1,421 @@ | |||
1 | /* | ||
2 | * Linux WiMAX | ||
3 | * Generic messaging interface between userspace and driver/device | ||
4 | * | ||
5 | * | ||
6 | * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com> | ||
7 | * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> | ||
8 | * | ||
9 | * This program is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU General Public License version | ||
11 | * 2 as published by the Free Software Foundation. | ||
12 | * | ||
13 | * This program is distributed in the hope that it will be useful, | ||
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
16 | * GNU General Public License for more details. | ||
17 | * | ||
18 | * You should have received a copy of the GNU General Public License | ||
19 | * along with this program; if not, write to the Free Software | ||
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA | ||
21 | * 02110-1301, USA. | ||
22 | * | ||
23 | * | ||
24 | * This implements a direct communication channel between user space and | ||
25 | * the driver/device, by which free form messages can be sent back and | ||
26 | * forth. | ||
27 | * | ||
28 | * This is intended for device-specific features, vendor quirks, etc. | ||
29 | * | ||
30 | * See include/net/wimax.h | ||
31 | * | ||
32 | * GENERIC NETLINK ENCODING AND CAPACITY | ||
33 | * | ||
34 | * A destination "pipe name" is added to each message; it is up to the | ||
35 | * drivers to assign or use those names (if using them at all). | ||
36 | * | ||
37 | * Messages are encoded as a binary netlink attribute using nla_put() | ||
38 | * using type NLA_UNSPEC (as some versions of libnl still in | ||
39 | * deployment don't yet understand NLA_BINARY). | ||
40 | * | ||
41 | * The maximum capacity of this transport is PAGESIZE per message (so | ||
42 | * the actual payload will be bit smaller depending on the | ||
43 | * netlink/generic netlink attributes and headers). | ||
44 | * | ||
45 | * RECEPTION OF MESSAGES | ||
46 | * | ||
47 | * When a message is received from user space, it is passed verbatim | ||
48 | * to the driver calling wimax_dev->op_msg_from_user(). The return | ||
49 | * value from this function is passed back to user space as an ack | ||
50 | * over the generic netlink protocol. | ||
51 | * | ||
52 | * The stack doesn't do any processing or interpretation of these | ||
53 | * messages. | ||
54 | * | ||
55 | * SENDING MESSAGES | ||
56 | * | ||
57 | * Messages can be sent with wimax_msg(). | ||
58 | * | ||
59 | * If the message delivery needs to happen on a different context to | ||
60 | * that of its creation, wimax_msg_alloc() can be used to get a | ||
61 | * pointer to the message that can be delivered later on with | ||
62 | * wimax_msg_send(). | ||
63 | * | ||
64 | * ROADMAP | ||
65 | * | ||
66 | * wimax_gnl_doit_msg_from_user() Process a message from user space | ||
67 | * wimax_dev_get_by_genl_info() | ||
68 | * wimax_dev->op_msg_from_user() Delivery of message to the driver | ||
69 | * | ||
70 | * wimax_msg() Send a message to user space | ||
71 | * wimax_msg_alloc() | ||
72 | * wimax_msg_send() | ||
73 | */ | ||
74 | #include <linux/device.h> | ||
75 | #include <net/genetlink.h> | ||
76 | #include <linux/netdevice.h> | ||
77 | #include <linux/wimax.h> | ||
78 | #include <linux/security.h> | ||
79 | #include "wimax-internal.h" | ||
80 | |||
81 | |||
82 | #define D_SUBMODULE op_msg | ||
83 | #include "debug-levels.h" | ||
84 | |||
85 | |||
86 | /** | ||
87 | * wimax_msg_alloc - Create a new skb for sending a message to userspace | ||
88 | * | ||
89 | * @wimax_dev: WiMAX device descriptor | ||
90 | * @pipe_name: "named pipe" the message will be sent to | ||
91 | * @msg: pointer to the message data to send | ||
92 | * @size: size of the message to send (in bytes), including the header. | ||
93 | * @gfp_flags: flags for memory allocation. | ||
94 | * | ||
95 | * Returns: %0 if ok, negative errno code on error | ||
96 | * | ||
97 | * Description: | ||
98 | * | ||
99 | * Allocates an skb that will contain the message to send to user | ||
100 | * space over the messaging pipe and initializes it, copying the | ||
101 | * payload. | ||
102 | * | ||
103 | * Once this call is done, you can deliver it with | ||
104 | * wimax_msg_send(). | ||
105 | * | ||
106 | * IMPORTANT: | ||
107 | * | ||
108 | * Don't use skb_push()/skb_pull()/skb_reserve() on the skb, as | ||
109 | * wimax_msg_send() depends on skb->data being placed at the | ||
110 | * beginning of the user message. | ||
111 | */ | ||
112 | struct sk_buff *wimax_msg_alloc(struct wimax_dev *wimax_dev, | ||
113 | const char *pipe_name, | ||
114 | const void *msg, size_t size, | ||
115 | gfp_t gfp_flags) | ||
116 | { | ||
117 | int result; | ||
118 | struct device *dev = wimax_dev->net_dev->dev.parent; | ||
119 | size_t msg_size; | ||
120 | void *genl_msg; | ||
121 | struct sk_buff *skb; | ||
122 | |||
123 | msg_size = nla_total_size(size) | ||
124 | + nla_total_size(sizeof(u32)) | ||
125 | + (pipe_name ? nla_total_size(strlen(pipe_name)) : 0); | ||
126 | result = -ENOMEM; | ||
127 | skb = genlmsg_new(msg_size, gfp_flags); | ||
128 | if (skb == NULL) | ||
129 | goto error_new; | ||
130 | genl_msg = genlmsg_put(skb, 0, 0, &wimax_gnl_family, | ||
131 | 0, WIMAX_GNL_OP_MSG_TO_USER); | ||
132 | if (genl_msg == NULL) { | ||
133 | dev_err(dev, "no memory to create generic netlink message\n"); | ||
134 | goto error_genlmsg_put; | ||
135 | } | ||
136 | result = nla_put_u32(skb, WIMAX_GNL_MSG_IFIDX, | ||
137 | wimax_dev->net_dev->ifindex); | ||
138 | if (result < 0) { | ||
139 | dev_err(dev, "no memory to add ifindex attribute\n"); | ||
140 | goto error_nla_put; | ||
141 | } | ||
142 | if (pipe_name) { | ||
143 | result = nla_put_string(skb, WIMAX_GNL_MSG_PIPE_NAME, | ||
144 | pipe_name); | ||
145 | if (result < 0) { | ||
146 | dev_err(dev, "no memory to add pipe_name attribute\n"); | ||
147 | goto error_nla_put; | ||
148 | } | ||
149 | } | ||
150 | result = nla_put(skb, WIMAX_GNL_MSG_DATA, size, msg); | ||
151 | if (result < 0) { | ||
152 | dev_err(dev, "no memory to add payload in attribute\n"); | ||
153 | goto error_nla_put; | ||
154 | } | ||
155 | genlmsg_end(skb, genl_msg); | ||
156 | return skb; | ||
157 | |||
158 | error_nla_put: | ||
159 | error_genlmsg_put: | ||
160 | error_new: | ||
161 | nlmsg_free(skb); | ||
162 | return ERR_PTR(result); | ||
163 | |||
164 | } | ||
165 | EXPORT_SYMBOL_GPL(wimax_msg_alloc); | ||
166 | |||
167 | |||
168 | /** | ||
169 | * wimax_msg_data_len - Return a pointer and size of a message's payload | ||
170 | * | ||
171 | * @msg: Pointer to a message created with wimax_msg_alloc() | ||
172 | * @size: Pointer to where to store the message's size | ||
173 | * | ||
174 | * Returns the pointer to the message data. | ||
175 | */ | ||
176 | const void *wimax_msg_data_len(struct sk_buff *msg, size_t *size) | ||
177 | { | ||
178 | struct nlmsghdr *nlh = (void *) msg->head; | ||
179 | struct nlattr *nla; | ||
180 | |||
181 | nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr), | ||
182 | WIMAX_GNL_MSG_DATA); | ||
183 | if (nla == NULL) { | ||
184 | printk(KERN_ERR "Cannot find attribute WIMAX_GNL_MSG_DATA\n"); | ||
185 | return NULL; | ||
186 | } | ||
187 | *size = nla_len(nla); | ||
188 | return nla_data(nla); | ||
189 | } | ||
190 | EXPORT_SYMBOL_GPL(wimax_msg_data_len); | ||
191 | |||
192 | |||
193 | /** | ||
194 | * wimax_msg_data - Return a pointer to a message's payload | ||
195 | * | ||
196 | * @msg: Pointer to a message created with wimax_msg_alloc() | ||
197 | */ | ||
198 | const void *wimax_msg_data(struct sk_buff *msg) | ||
199 | { | ||
200 | struct nlmsghdr *nlh = (void *) msg->head; | ||
201 | struct nlattr *nla; | ||
202 | |||
203 | nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr), | ||
204 | WIMAX_GNL_MSG_DATA); | ||
205 | if (nla == NULL) { | ||
206 | printk(KERN_ERR "Cannot find attribute WIMAX_GNL_MSG_DATA\n"); | ||
207 | return NULL; | ||
208 | } | ||
209 | return nla_data(nla); | ||
210 | } | ||
211 | EXPORT_SYMBOL_GPL(wimax_msg_data); | ||
212 | |||
213 | |||
214 | /** | ||
215 | * wimax_msg_len - Return a message's payload length | ||
216 | * | ||
217 | * @msg: Pointer to a message created with wimax_msg_alloc() | ||
218 | */ | ||
219 | ssize_t wimax_msg_len(struct sk_buff *msg) | ||
220 | { | ||
221 | struct nlmsghdr *nlh = (void *) msg->head; | ||
222 | struct nlattr *nla; | ||
223 | |||
224 | nla = nlmsg_find_attr(nlh, sizeof(struct genlmsghdr), | ||
225 | WIMAX_GNL_MSG_DATA); | ||
226 | if (nla == NULL) { | ||
227 | printk(KERN_ERR "Cannot find attribute WIMAX_GNL_MSG_DATA\n"); | ||
228 | return -EINVAL; | ||
229 | } | ||
230 | return nla_len(nla); | ||
231 | } | ||
232 | EXPORT_SYMBOL_GPL(wimax_msg_len); | ||
233 | |||
234 | |||
235 | /** | ||
236 | * wimax_msg_send - Send a pre-allocated message to user space | ||
237 | * | ||
238 | * @wimax_dev: WiMAX device descriptor | ||
239 | * | ||
240 | * @skb: &struct sk_buff returned by wimax_msg_alloc(). Note the | ||
241 | * ownership of @skb is transferred to this function. | ||
242 | * | ||
243 | * Returns: 0 if ok, < 0 errno code on error | ||
244 | * | ||
245 | * Description: | ||
246 | * | ||
247 | * Sends a free-form message that was preallocated with | ||
248 | * wimax_msg_alloc() and filled up. | ||
249 | * | ||
250 | * Assumes that once you pass an skb to this function for sending, it | ||
251 | * owns it and will release it when done (on success). | ||
252 | * | ||
253 | * IMPORTANT: | ||
254 | * | ||
255 | * Don't use skb_push()/skb_pull()/skb_reserve() on the skb, as | ||
256 | * wimax_msg_send() depends on skb->data being placed at the | ||
257 | * beginning of the user message. | ||
258 | */ | ||
259 | int wimax_msg_send(struct wimax_dev *wimax_dev, struct sk_buff *skb) | ||
260 | { | ||
261 | int result; | ||
262 | struct device *dev = wimax_dev->net_dev->dev.parent; | ||
263 | void *msg = skb->data; | ||
264 | size_t size = skb->len; | ||
265 | might_sleep(); | ||
266 | |||
267 | d_printf(1, dev, "CTX: wimax msg, %zu bytes\n", size); | ||
268 | d_dump(2, dev, msg, size); | ||
269 | result = genlmsg_multicast(skb, 0, wimax_gnl_mcg.id, GFP_KERNEL); | ||
270 | d_printf(1, dev, "CTX: genl multicast result %d\n", result); | ||
271 | if (result == -ESRCH) /* Nobody connected, ignore it */ | ||
272 | result = 0; /* btw, the skb is freed already */ | ||
273 | return result; | ||
274 | } | ||
275 | EXPORT_SYMBOL_GPL(wimax_msg_send); | ||
276 | |||
277 | |||
278 | /** | ||
279 | * wimax_msg - Send a message to user space | ||
280 | * | ||
281 | * @wimax_dev: WiMAX device descriptor (properly referenced) | ||
282 | * @pipe_name: "named pipe" the message will be sent to | ||
283 | * @buf: pointer to the message to send. | ||
284 | * @size: size of the buffer pointed to by @buf (in bytes). | ||
285 | * @gfp_flags: flags for memory allocation. | ||
286 | * | ||
287 | * Returns: %0 if ok, negative errno code on error. | ||
288 | * | ||
289 | * Description: | ||
290 | * | ||
291 | * Sends a free-form message to user space on the device @wimax_dev. | ||
292 | * | ||
293 | * NOTES: | ||
294 | * | ||
295 | * Once the @skb is given to this function, who will own it and will | ||
296 | * release it when done (unless it returns error). | ||
297 | */ | ||
298 | int wimax_msg(struct wimax_dev *wimax_dev, const char *pipe_name, | ||
299 | const void *buf, size_t size, gfp_t gfp_flags) | ||
300 | { | ||
301 | int result = -ENOMEM; | ||
302 | struct sk_buff *skb; | ||
303 | |||
304 | skb = wimax_msg_alloc(wimax_dev, pipe_name, buf, size, gfp_flags); | ||
305 | if (skb == NULL) | ||
306 | goto error_msg_new; | ||
307 | result = wimax_msg_send(wimax_dev, skb); | ||
308 | error_msg_new: | ||
309 | return result; | ||
310 | } | ||
311 | EXPORT_SYMBOL_GPL(wimax_msg); | ||
312 | |||
313 | |||
314 | static const | ||
315 | struct nla_policy wimax_gnl_msg_policy[WIMAX_GNL_ATTR_MAX + 1] = { | ||
316 | [WIMAX_GNL_MSG_IFIDX] = { | ||
317 | .type = NLA_U32, | ||
318 | }, | ||
319 | [WIMAX_GNL_MSG_DATA] = { | ||
320 | .type = NLA_UNSPEC, /* libnl doesn't grok BINARY yet */ | ||
321 | }, | ||
322 | }; | ||
323 | |||
324 | |||
325 | /* | ||
326 | * Relays a message from user space to the driver | ||
327 | * | ||
328 | * The skb is passed to the driver-specific function with the netlink | ||
329 | * and generic netlink headers already stripped. | ||
330 | * | ||
331 | * This call will block while handling/relaying the message. | ||
332 | */ | ||
333 | static | ||
334 | int wimax_gnl_doit_msg_from_user(struct sk_buff *skb, struct genl_info *info) | ||
335 | { | ||
336 | int result, ifindex; | ||
337 | struct wimax_dev *wimax_dev; | ||
338 | struct device *dev; | ||
339 | struct nlmsghdr *nlh = info->nlhdr; | ||
340 | char *pipe_name; | ||
341 | void *msg_buf; | ||
342 | size_t msg_len; | ||
343 | |||
344 | might_sleep(); | ||
345 | d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info); | ||
346 | result = -ENODEV; | ||
347 | if (info->attrs[WIMAX_GNL_MSG_IFIDX] == NULL) { | ||
348 | printk(KERN_ERR "WIMAX_GNL_MSG_FROM_USER: can't find IFIDX " | ||
349 | "attribute\n"); | ||
350 | goto error_no_wimax_dev; | ||
351 | } | ||
352 | ifindex = nla_get_u32(info->attrs[WIMAX_GNL_MSG_IFIDX]); | ||
353 | wimax_dev = wimax_dev_get_by_genl_info(info, ifindex); | ||
354 | if (wimax_dev == NULL) | ||
355 | goto error_no_wimax_dev; | ||
356 | dev = wimax_dev_to_dev(wimax_dev); | ||
357 | |||
358 | /* Unpack arguments */ | ||
359 | result = -EINVAL; | ||
360 | if (info->attrs[WIMAX_GNL_MSG_DATA] == NULL) { | ||
361 | dev_err(dev, "WIMAX_GNL_MSG_FROM_USER: can't find MSG_DATA " | ||
362 | "attribute\n"); | ||
363 | goto error_no_data; | ||
364 | } | ||
365 | msg_buf = nla_data(info->attrs[WIMAX_GNL_MSG_DATA]); | ||
366 | msg_len = nla_len(info->attrs[WIMAX_GNL_MSG_DATA]); | ||
367 | |||
368 | if (info->attrs[WIMAX_GNL_MSG_PIPE_NAME] == NULL) | ||
369 | pipe_name = NULL; | ||
370 | else { | ||
371 | struct nlattr *attr = info->attrs[WIMAX_GNL_MSG_PIPE_NAME]; | ||
372 | size_t attr_len = nla_len(attr); | ||
373 | /* libnl-1.1 does not yet support NLA_NUL_STRING */ | ||
374 | result = -ENOMEM; | ||
375 | pipe_name = kstrndup(nla_data(attr), attr_len + 1, GFP_KERNEL); | ||
376 | if (pipe_name == NULL) | ||
377 | goto error_alloc; | ||
378 | pipe_name[attr_len] = 0; | ||
379 | } | ||
380 | mutex_lock(&wimax_dev->mutex); | ||
381 | result = wimax_dev_is_ready(wimax_dev); | ||
382 | if (result < 0) | ||
383 | goto error_not_ready; | ||
384 | result = -ENOSYS; | ||
385 | if (wimax_dev->op_msg_from_user == NULL) | ||
386 | goto error_noop; | ||
387 | |||
388 | d_printf(1, dev, | ||
389 | "CRX: nlmsghdr len %u type %u flags 0x%04x seq 0x%x pid %u\n", | ||
390 | nlh->nlmsg_len, nlh->nlmsg_type, nlh->nlmsg_flags, | ||
391 | nlh->nlmsg_seq, nlh->nlmsg_pid); | ||
392 | d_printf(1, dev, "CRX: wimax message %zu bytes\n", msg_len); | ||
393 | d_dump(2, dev, msg_buf, msg_len); | ||
394 | |||
395 | result = wimax_dev->op_msg_from_user(wimax_dev, pipe_name, | ||
396 | msg_buf, msg_len, info); | ||
397 | error_noop: | ||
398 | error_not_ready: | ||
399 | mutex_unlock(&wimax_dev->mutex); | ||
400 | error_alloc: | ||
401 | kfree(pipe_name); | ||
402 | error_no_data: | ||
403 | dev_put(wimax_dev->net_dev); | ||
404 | error_no_wimax_dev: | ||
405 | d_fnend(3, NULL, "(skb %p info %p) = %d\n", skb, info, result); | ||
406 | return result; | ||
407 | } | ||
408 | |||
409 | |||
410 | /* | ||
411 | * Generic Netlink glue | ||
412 | */ | ||
413 | |||
414 | struct genl_ops wimax_gnl_msg_from_user = { | ||
415 | .cmd = WIMAX_GNL_OP_MSG_FROM_USER, | ||
416 | .flags = GENL_ADMIN_PERM, | ||
417 | .policy = wimax_gnl_msg_policy, | ||
418 | .doit = wimax_gnl_doit_msg_from_user, | ||
419 | .dumpit = NULL, | ||
420 | }; | ||
421 | |||