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64e04910 DB |
1 | /* |
2 | * Host Side support for RNDIS Networking Links | |
3 | * Copyright (C) 2005 by David Brownell | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | ||
20 | // #define DEBUG // error path messages, extra info | |
21 | // #define VERBOSE // more; success messages | |
22 | ||
23 | #include <linux/config.h> | |
24 | #ifdef CONFIG_USB_DEBUG | |
25 | # define DEBUG | |
26 | #endif | |
27 | #include <linux/module.h> | |
28 | #include <linux/sched.h> | |
29 | #include <linux/init.h> | |
30 | #include <linux/netdevice.h> | |
31 | #include <linux/etherdevice.h> | |
32 | #include <linux/ethtool.h> | |
33 | #include <linux/workqueue.h> | |
34 | #include <linux/mii.h> | |
35 | #include <linux/usb.h> | |
36 | #include <linux/usb_cdc.h> | |
37 | ||
38 | #include "usbnet.h" | |
39 | ||
40 | ||
41 | /* | |
42 | * RNDIS is NDIS remoted over USB. It's a MSFT variant of CDC ACM ... of | |
43 | * course ACM was intended for modems, not Ethernet links! USB's standard | |
44 | * for Ethernet links is "CDC Ethernet", which is significantly simpler. | |
45 | */ | |
46 | ||
47 | /* | |
48 | * CONTROL uses CDC "encapsulated commands" with funky notifications. | |
49 | * - control-out: SEND_ENCAPSULATED | |
50 | * - interrupt-in: RESPONSE_AVAILABLE | |
51 | * - control-in: GET_ENCAPSULATED | |
52 | * | |
53 | * We'll try to ignore the RESPONSE_AVAILABLE notifications. | |
54 | */ | |
55 | struct rndis_msg_hdr { | |
56 | __le32 msg_type; /* RNDIS_MSG_* */ | |
57 | __le32 msg_len; | |
58 | // followed by data that varies between messages | |
59 | __le32 request_id; | |
60 | __le32 status; | |
61 | // ... and more | |
62 | } __attribute__ ((packed)); | |
63 | ||
64 | /* RNDIS defines this (absurdly huge) control timeout */ | |
65 | #define RNDIS_CONTROL_TIMEOUT_MS (10 * 1000) | |
66 | ||
67 | ||
68 | #define ccpu2 __constant_cpu_to_le32 | |
69 | ||
70 | #define RNDIS_MSG_COMPLETION ccpu2(0x80000000) | |
71 | ||
72 | /* codes for "msg_type" field of rndis messages; | |
73 | * only the data channel uses packet messages (maybe batched); | |
74 | * everything else goes on the control channel. | |
75 | */ | |
76 | #define RNDIS_MSG_PACKET ccpu2(0x00000001) /* 1-N packets */ | |
77 | #define RNDIS_MSG_INIT ccpu2(0x00000002) | |
78 | #define RNDIS_MSG_INIT_C (RNDIS_MSG_INIT|RNDIS_MSG_COMPLETION) | |
79 | #define RNDIS_MSG_HALT ccpu2(0x00000003) | |
80 | #define RNDIS_MSG_QUERY ccpu2(0x00000004) | |
81 | #define RNDIS_MSG_QUERY_C (RNDIS_MSG_QUERY|RNDIS_MSG_COMPLETION) | |
82 | #define RNDIS_MSG_SET ccpu2(0x00000005) | |
83 | #define RNDIS_MSG_SET_C (RNDIS_MSG_SET|RNDIS_MSG_COMPLETION) | |
84 | #define RNDIS_MSG_RESET ccpu2(0x00000006) | |
85 | #define RNDIS_MSG_RESET_C (RNDIS_MSG_RESET|RNDIS_MSG_COMPLETION) | |
86 | #define RNDIS_MSG_INDICATE ccpu2(0x00000007) | |
87 | #define RNDIS_MSG_KEEPALIVE ccpu2(0x00000008) | |
88 | #define RNDIS_MSG_KEEPALIVE_C (RNDIS_MSG_KEEPALIVE|RNDIS_MSG_COMPLETION) | |
89 | ||
90 | /* codes for "status" field of completion messages */ | |
91 | #define RNDIS_STATUS_SUCCESS ccpu2(0x00000000) | |
92 | #define RNDIS_STATUS_FAILURE ccpu2(0xc0000001) | |
93 | #define RNDIS_STATUS_INVALID_DATA ccpu2(0xc0010015) | |
94 | #define RNDIS_STATUS_NOT_SUPPORTED ccpu2(0xc00000bb) | |
95 | #define RNDIS_STATUS_MEDIA_CONNECT ccpu2(0x4001000b) | |
96 | #define RNDIS_STATUS_MEDIA_DISCONNECT ccpu2(0x4001000c) | |
97 | ||
98 | ||
99 | struct rndis_data_hdr { | |
100 | __le32 msg_type; /* RNDIS_MSG_PACKET */ | |
101 | __le32 msg_len; // rndis_data_hdr + data_len + pad | |
102 | __le32 data_offset; // 36 -- right after header | |
103 | __le32 data_len; // ... real packet size | |
104 | ||
105 | __le32 oob_data_offset; // zero | |
106 | __le32 oob_data_len; // zero | |
107 | __le32 num_oob; // zero | |
108 | __le32 packet_data_offset; // zero | |
109 | ||
110 | __le32 packet_data_len; // zero | |
111 | __le32 vc_handle; // zero | |
112 | __le32 reserved; // zero | |
113 | } __attribute__ ((packed)); | |
114 | ||
115 | struct rndis_init { /* OUT */ | |
116 | // header and: | |
117 | __le32 msg_type; /* RNDIS_MSG_INIT */ | |
118 | __le32 msg_len; // 24 | |
119 | __le32 request_id; | |
120 | __le32 major_version; // of rndis (1.0) | |
121 | __le32 minor_version; | |
122 | __le32 max_transfer_size; | |
123 | } __attribute__ ((packed)); | |
124 | ||
125 | struct rndis_init_c { /* IN */ | |
126 | // header and: | |
127 | __le32 msg_type; /* RNDIS_MSG_INIT_C */ | |
128 | __le32 msg_len; | |
129 | __le32 request_id; | |
130 | __le32 status; | |
131 | __le32 major_version; // of rndis (1.0) | |
132 | __le32 minor_version; | |
133 | __le32 device_flags; | |
134 | __le32 medium; // zero == 802.3 | |
135 | __le32 max_packets_per_message; | |
136 | __le32 max_transfer_size; | |
137 | __le32 packet_alignment; // max 7; (1<<n) bytes | |
138 | __le32 af_list_offset; // zero | |
139 | __le32 af_list_size; // zero | |
140 | } __attribute__ ((packed)); | |
141 | ||
142 | struct rndis_halt { /* OUT (no reply) */ | |
143 | // header and: | |
144 | __le32 msg_type; /* RNDIS_MSG_HALT */ | |
145 | __le32 msg_len; | |
146 | __le32 request_id; | |
147 | } __attribute__ ((packed)); | |
148 | ||
149 | struct rndis_query { /* OUT */ | |
150 | // header and: | |
151 | __le32 msg_type; /* RNDIS_MSG_QUERY */ | |
152 | __le32 msg_len; | |
153 | __le32 request_id; | |
154 | __le32 oid; | |
155 | __le32 len; | |
156 | __le32 offset; | |
157 | /*?*/ __le32 handle; // zero | |
158 | } __attribute__ ((packed)); | |
159 | ||
160 | struct rndis_query_c { /* IN */ | |
161 | // header and: | |
162 | __le32 msg_type; /* RNDIS_MSG_QUERY_C */ | |
163 | __le32 msg_len; | |
164 | __le32 request_id; | |
165 | __le32 status; | |
166 | __le32 len; | |
167 | __le32 offset; | |
168 | } __attribute__ ((packed)); | |
169 | ||
170 | struct rndis_set { /* OUT */ | |
171 | // header and: | |
172 | __le32 msg_type; /* RNDIS_MSG_SET */ | |
173 | __le32 msg_len; | |
174 | __le32 request_id; | |
175 | __le32 oid; | |
176 | __le32 len; | |
177 | __le32 offset; | |
178 | /*?*/ __le32 handle; // zero | |
179 | } __attribute__ ((packed)); | |
180 | ||
181 | struct rndis_set_c { /* IN */ | |
182 | // header and: | |
183 | __le32 msg_type; /* RNDIS_MSG_SET_C */ | |
184 | __le32 msg_len; | |
185 | __le32 request_id; | |
186 | __le32 status; | |
187 | } __attribute__ ((packed)); | |
188 | ||
189 | struct rndis_reset { /* IN */ | |
190 | // header and: | |
191 | __le32 msg_type; /* RNDIS_MSG_RESET */ | |
192 | __le32 msg_len; | |
193 | __le32 reserved; | |
194 | } __attribute__ ((packed)); | |
195 | ||
196 | struct rndis_reset_c { /* OUT */ | |
197 | // header and: | |
198 | __le32 msg_type; /* RNDIS_MSG_RESET_C */ | |
199 | __le32 msg_len; | |
200 | __le32 status; | |
201 | __le32 addressing_lost; | |
202 | } __attribute__ ((packed)); | |
203 | ||
204 | struct rndis_indicate { /* IN (unrequested) */ | |
205 | // header and: | |
206 | __le32 msg_type; /* RNDIS_MSG_INDICATE */ | |
207 | __le32 msg_len; | |
208 | __le32 status; | |
209 | __le32 length; | |
210 | __le32 offset; | |
211 | /**/ __le32 diag_status; | |
212 | __le32 error_offset; | |
213 | /**/ __le32 message; | |
214 | } __attribute__ ((packed)); | |
215 | ||
216 | struct rndis_keepalive { /* OUT (optionally IN) */ | |
217 | // header and: | |
218 | __le32 msg_type; /* RNDIS_MSG_KEEPALIVE */ | |
219 | __le32 msg_len; | |
220 | __le32 request_id; | |
221 | } __attribute__ ((packed)); | |
222 | ||
223 | struct rndis_keepalive_c { /* IN (optionally OUT) */ | |
224 | // header and: | |
225 | __le32 msg_type; /* RNDIS_MSG_KEEPALIVE_C */ | |
226 | __le32 msg_len; | |
227 | __le32 request_id; | |
228 | __le32 status; | |
229 | } __attribute__ ((packed)); | |
230 | ||
231 | /* NOTE: about 30 OIDs are "mandatory" for peripherals to support ... and | |
232 | * there are gobs more that may optionally be supported. We'll avoid as much | |
233 | * of that mess as possible. | |
234 | */ | |
235 | #define OID_802_3_PERMANENT_ADDRESS ccpu2(0x01010101) | |
236 | #define OID_GEN_CURRENT_PACKET_FILTER ccpu2(0x0001010e) | |
237 | ||
238 | /* | |
239 | * RNDIS notifications from device: command completion; "reverse" | |
240 | * keepalives; etc | |
241 | */ | |
242 | static void rndis_status(struct usbnet *dev, struct urb *urb) | |
243 | { | |
244 | devdbg(dev, "rndis status urb, len %d stat %d", | |
245 | urb->actual_length, urb->status); | |
246 | // FIXME for keepalives, respond immediately (asynchronously) | |
247 | // if not an RNDIS status, do like cdc_status(dev,urb) does | |
248 | } | |
249 | ||
250 | /* | |
251 | * RPC done RNDIS-style. Caller guarantees: | |
252 | * - message is properly byteswapped | |
253 | * - there's no other request pending | |
254 | * - buf can hold up to 1KB response (required by RNDIS spec) | |
255 | * On return, the first few entries are already byteswapped. | |
256 | * | |
257 | * Call context is likely probe(), before interface name is known, | |
258 | * which is why we won't try to use it in the diagnostics. | |
259 | */ | |
260 | static int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf) | |
261 | { | |
262 | struct cdc_state *info = (void *) &dev->data; | |
263 | int retval; | |
264 | unsigned count; | |
265 | __le32 rsp; | |
266 | u32 xid = 0, msg_len, request_id; | |
267 | ||
268 | /* REVISIT when this gets called from contexts other than probe() or | |
269 | * disconnect(): either serialize, or dispatch responses on xid | |
270 | */ | |
271 | ||
272 | /* Issue the request; don't bother byteswapping our xid */ | |
273 | if (likely(buf->msg_type != RNDIS_MSG_HALT | |
274 | && buf->msg_type != RNDIS_MSG_RESET)) { | |
275 | xid = dev->xid++; | |
276 | if (!xid) | |
277 | xid = dev->xid++; | |
278 | buf->request_id = (__force __le32) xid; | |
279 | } | |
280 | retval = usb_control_msg(dev->udev, | |
281 | usb_sndctrlpipe(dev->udev, 0), | |
282 | USB_CDC_SEND_ENCAPSULATED_COMMAND, | |
283 | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
284 | 0, info->u->bMasterInterface0, | |
285 | buf, le32_to_cpu(buf->msg_len), | |
286 | RNDIS_CONTROL_TIMEOUT_MS); | |
287 | if (unlikely(retval < 0 || xid == 0)) | |
288 | return retval; | |
289 | ||
290 | // FIXME Seems like some devices discard responses when | |
291 | // we time out and cancel our "get response" requests... | |
292 | // so, this is fragile. Probably need to poll for status. | |
293 | ||
294 | /* ignore status endpoint, just poll the control channel; | |
295 | * the request probably completed immediately | |
296 | */ | |
297 | rsp = buf->msg_type | RNDIS_MSG_COMPLETION; | |
298 | for (count = 0; count < 10; count++) { | |
299 | memset(buf, 0, 1024); | |
300 | retval = usb_control_msg(dev->udev, | |
301 | usb_rcvctrlpipe(dev->udev, 0), | |
302 | USB_CDC_GET_ENCAPSULATED_RESPONSE, | |
303 | USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
304 | 0, info->u->bMasterInterface0, | |
305 | buf, 1024, | |
306 | RNDIS_CONTROL_TIMEOUT_MS); | |
307 | if (likely(retval >= 8)) { | |
308 | msg_len = le32_to_cpu(buf->msg_len); | |
309 | request_id = (__force u32) buf->request_id; | |
310 | if (likely(buf->msg_type == rsp)) { | |
311 | if (likely(request_id == xid)) { | |
312 | if (unlikely(rsp == RNDIS_MSG_RESET_C)) | |
313 | return 0; | |
314 | if (likely(RNDIS_STATUS_SUCCESS | |
315 | == buf->status)) | |
316 | return 0; | |
317 | dev_dbg(&info->control->dev, | |
318 | "rndis reply status %08x\n", | |
319 | le32_to_cpu(buf->status)); | |
320 | return -EL3RST; | |
321 | } | |
322 | dev_dbg(&info->control->dev, | |
323 | "rndis reply id %d expected %d\n", | |
324 | request_id, xid); | |
325 | /* then likely retry */ | |
326 | } else switch (buf->msg_type) { | |
327 | case RNDIS_MSG_INDICATE: { /* fault */ | |
328 | // struct rndis_indicate *msg = (void *)buf; | |
329 | dev_info(&info->control->dev, | |
330 | "rndis fault indication\n"); | |
331 | } | |
332 | break; | |
333 | case RNDIS_MSG_KEEPALIVE: { /* ping */ | |
334 | struct rndis_keepalive_c *msg = (void *)buf; | |
335 | ||
336 | msg->msg_type = RNDIS_MSG_KEEPALIVE_C; | |
337 | msg->msg_len = ccpu2(sizeof *msg); | |
338 | msg->status = RNDIS_STATUS_SUCCESS; | |
339 | retval = usb_control_msg(dev->udev, | |
340 | usb_sndctrlpipe(dev->udev, 0), | |
341 | USB_CDC_SEND_ENCAPSULATED_COMMAND, | |
342 | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
343 | 0, info->u->bMasterInterface0, | |
344 | msg, sizeof *msg, | |
345 | RNDIS_CONTROL_TIMEOUT_MS); | |
346 | if (unlikely(retval < 0)) | |
347 | dev_dbg(&info->control->dev, | |
348 | "rndis keepalive err %d\n", | |
349 | retval); | |
350 | } | |
351 | break; | |
352 | default: | |
353 | dev_dbg(&info->control->dev, | |
354 | "unexpected rndis msg %08x len %d\n", | |
355 | le32_to_cpu(buf->msg_type), msg_len); | |
356 | } | |
357 | } else { | |
358 | /* device probably issued a protocol stall; ignore */ | |
359 | dev_dbg(&info->control->dev, | |
360 | "rndis response error, code %d\n", retval); | |
361 | } | |
362 | msleep(2); | |
363 | } | |
364 | dev_dbg(&info->control->dev, "rndis response timeout\n"); | |
365 | return -ETIMEDOUT; | |
366 | } | |
367 | ||
368 | static int rndis_bind(struct usbnet *dev, struct usb_interface *intf) | |
369 | { | |
370 | int retval; | |
371 | struct net_device *net = dev->net; | |
372 | union { | |
373 | void *buf; | |
374 | struct rndis_msg_hdr *header; | |
375 | struct rndis_init *init; | |
376 | struct rndis_init_c *init_c; | |
377 | struct rndis_query *get; | |
378 | struct rndis_query_c *get_c; | |
379 | struct rndis_set *set; | |
380 | struct rndis_set_c *set_c; | |
381 | } u; | |
382 | u32 tmp; | |
383 | ||
384 | /* we can't rely on i/o from stack working, or stack allocation */ | |
385 | u.buf = kmalloc(1024, GFP_KERNEL); | |
386 | if (!u.buf) | |
387 | return -ENOMEM; | |
388 | retval = usbnet_generic_cdc_bind(dev, intf); | |
389 | if (retval < 0) | |
390 | goto done; | |
391 | ||
392 | net->hard_header_len += sizeof (struct rndis_data_hdr); | |
393 | ||
394 | /* initialize; max transfer is 16KB at full speed */ | |
395 | u.init->msg_type = RNDIS_MSG_INIT; | |
396 | u.init->msg_len = ccpu2(sizeof *u.init); | |
397 | u.init->major_version = ccpu2(1); | |
398 | u.init->minor_version = ccpu2(0); | |
399 | u.init->max_transfer_size = ccpu2(net->mtu + net->hard_header_len); | |
400 | ||
401 | retval = rndis_command(dev, u.header); | |
402 | if (unlikely(retval < 0)) { | |
403 | /* it might not even be an RNDIS device!! */ | |
404 | dev_err(&intf->dev, "RNDIS init failed, %d\n", retval); | |
405 | fail: | |
406 | usb_driver_release_interface(driver_of(intf), | |
407 | ((struct cdc_state *)&(dev->data))->data); | |
408 | goto done; | |
409 | } | |
410 | dev->hard_mtu = le32_to_cpu(u.init_c->max_transfer_size); | |
411 | /* REVISIT: peripheral "alignment" request is ignored ... */ | |
412 | dev_dbg(&intf->dev, "hard mtu %u, align %d\n", dev->hard_mtu, | |
413 | 1 << le32_to_cpu(u.init_c->packet_alignment)); | |
414 | ||
415 | /* get designated host ethernet address */ | |
416 | memset(u.get, 0, sizeof *u.get); | |
417 | u.get->msg_type = RNDIS_MSG_QUERY; | |
418 | u.get->msg_len = ccpu2(sizeof *u.get); | |
419 | u.get->oid = OID_802_3_PERMANENT_ADDRESS; | |
420 | ||
421 | retval = rndis_command(dev, u.header); | |
422 | if (unlikely(retval < 0)) { | |
423 | dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval); | |
424 | goto fail; | |
425 | } | |
426 | tmp = le32_to_cpu(u.get_c->offset); | |
427 | if (unlikely((tmp + 8) > (1024 - ETH_ALEN) | |
428 | || u.get_c->len != ccpu2(ETH_ALEN))) { | |
429 | dev_err(&intf->dev, "rndis ethaddr off %d len %d ?\n", | |
430 | tmp, le32_to_cpu(u.get_c->len)); | |
431 | retval = -EDOM; | |
432 | goto fail; | |
433 | } | |
434 | memcpy(net->dev_addr, tmp + (char *)&u.get_c->request_id, ETH_ALEN); | |
435 | ||
436 | /* set a nonzero filter to enable data transfers */ | |
437 | memset(u.set, 0, sizeof *u.set); | |
438 | u.set->msg_type = RNDIS_MSG_SET; | |
439 | u.set->msg_len = ccpu2(4 + sizeof *u.set); | |
440 | u.set->oid = OID_GEN_CURRENT_PACKET_FILTER; | |
441 | u.set->len = ccpu2(4); | |
442 | u.set->offset = ccpu2((sizeof *u.set) - 8); | |
443 | *(__le32 *)(u.buf + sizeof *u.set) = ccpu2(DEFAULT_FILTER); | |
444 | ||
445 | retval = rndis_command(dev, u.header); | |
446 | if (unlikely(retval < 0)) { | |
447 | dev_err(&intf->dev, "rndis set packet filter, %d\n", retval); | |
448 | goto fail; | |
449 | } | |
450 | ||
451 | retval = 0; | |
452 | done: | |
453 | kfree(u.buf); | |
454 | return retval; | |
455 | } | |
456 | ||
457 | static void rndis_unbind(struct usbnet *dev, struct usb_interface *intf) | |
458 | { | |
459 | struct rndis_halt *halt; | |
460 | ||
461 | /* try to clear any rndis state/activity (no i/o from stack!) */ | |
462 | halt = kcalloc(1, sizeof *halt, SLAB_KERNEL); | |
463 | if (halt) { | |
464 | halt->msg_type = RNDIS_MSG_HALT; | |
465 | halt->msg_len = ccpu2(sizeof *halt); | |
466 | (void) rndis_command(dev, (void *)halt); | |
467 | kfree(halt); | |
468 | } | |
469 | ||
470 | return usbnet_cdc_unbind(dev, intf); | |
471 | } | |
472 | ||
473 | /* | |
474 | * DATA -- host must not write zlps | |
475 | */ | |
476 | static int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb) | |
477 | { | |
478 | /* peripheral may have batched packets to us... */ | |
479 | while (likely(skb->len)) { | |
480 | struct rndis_data_hdr *hdr = (void *)skb->data; | |
481 | struct sk_buff *skb2; | |
482 | u32 msg_len, data_offset, data_len; | |
483 | ||
484 | msg_len = le32_to_cpu(hdr->msg_len); | |
485 | data_offset = le32_to_cpu(hdr->data_offset); | |
486 | data_len = le32_to_cpu(hdr->data_len); | |
487 | ||
488 | /* don't choke if we see oob, per-packet data, etc */ | |
489 | if (unlikely(hdr->msg_type != RNDIS_MSG_PACKET | |
490 | || skb->len < msg_len | |
491 | || (data_offset + data_len + 8) > msg_len)) { | |
492 | dev->stats.rx_frame_errors++; | |
493 | devdbg(dev, "bad rndis message %d/%d/%d/%d, len %d", | |
494 | le32_to_cpu(hdr->msg_type), | |
495 | msg_len, data_offset, data_len, skb->len); | |
496 | return 0; | |
497 | } | |
498 | skb_pull(skb, 8 + data_offset); | |
499 | ||
500 | /* at most one packet left? */ | |
501 | if (likely((data_len - skb->len) <= sizeof *hdr)) { | |
502 | skb_trim(skb, data_len); | |
503 | break; | |
504 | } | |
505 | ||
506 | /* try to return all the packets in the batch */ | |
507 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
508 | if (unlikely(!skb2)) | |
509 | break; | |
510 | skb_pull(skb, msg_len - sizeof *hdr); | |
511 | skb_trim(skb2, data_len); | |
512 | usbnet_skb_return(dev, skb2); | |
513 | } | |
514 | ||
515 | /* caller will usbnet_skb_return the remaining packet */ | |
516 | return 1; | |
517 | } | |
518 | ||
519 | static struct sk_buff * | |
520 | rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, unsigned flags) | |
521 | { | |
522 | struct rndis_data_hdr *hdr; | |
523 | struct sk_buff *skb2; | |
524 | unsigned len = skb->len; | |
525 | ||
526 | if (likely(!skb_cloned(skb))) { | |
527 | int room = skb_headroom(skb); | |
528 | ||
529 | /* enough head room as-is? */ | |
530 | if (unlikely((sizeof *hdr) <= room)) | |
531 | goto fill; | |
532 | ||
533 | /* enough room, but needs to be readjusted? */ | |
534 | room += skb_tailroom(skb); | |
535 | if (likely((sizeof *hdr) <= room)) { | |
536 | skb->data = memmove(skb->head + sizeof *hdr, | |
537 | skb->data, len); | |
538 | skb->tail = skb->data + len; | |
539 | goto fill; | |
540 | } | |
541 | } | |
542 | ||
543 | /* create a new skb, with the correct size (and tailpad) */ | |
544 | skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags); | |
545 | dev_kfree_skb_any(skb); | |
546 | if (unlikely(!skb2)) | |
547 | return skb2; | |
548 | skb = skb2; | |
549 | ||
550 | /* fill out the RNDIS header. we won't bother trying to batch | |
551 | * packets; Linux minimizes wasted bandwidth through tx queues. | |
552 | */ | |
553 | fill: | |
554 | hdr = (void *) __skb_push(skb, sizeof *hdr); | |
555 | memset(hdr, 0, sizeof *hdr); | |
556 | hdr->msg_type = RNDIS_MSG_PACKET; | |
557 | hdr->msg_len = cpu_to_le32(skb->len); | |
558 | hdr->data_offset = ccpu2(sizeof(*hdr) - 8); | |
559 | hdr->data_len = cpu_to_le32(len); | |
560 | ||
561 | /* FIXME make the last packet always be short ... */ | |
562 | return skb; | |
563 | } | |
564 | ||
565 | ||
566 | static const struct driver_info rndis_info = { | |
567 | .description = "RNDIS device", | |
568 | .flags = FLAG_ETHER | FLAG_FRAMING_RN, | |
569 | .bind = rndis_bind, | |
570 | .unbind = rndis_unbind, | |
571 | .status = rndis_status, | |
572 | .rx_fixup = rndis_rx_fixup, | |
573 | .tx_fixup = rndis_tx_fixup, | |
574 | }; | |
575 | ||
576 | #undef ccpu2 | |
577 | ||
578 | ||
579 | /*-------------------------------------------------------------------------*/ | |
580 | ||
581 | static const struct usb_device_id products [] = { | |
582 | { | |
583 | /* RNDIS is MSFT's un-official variant of CDC ACM */ | |
584 | USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff), | |
585 | .driver_info = (unsigned long) &rndis_info, | |
586 | }, | |
587 | { }, // END | |
588 | }; | |
589 | MODULE_DEVICE_TABLE(usb, products); | |
590 | ||
591 | static struct usb_driver rndis_driver = { | |
592 | .owner = THIS_MODULE, | |
593 | .name = "rndis_host", | |
594 | .id_table = products, | |
595 | .probe = usbnet_probe, | |
596 | .disconnect = usbnet_disconnect, | |
597 | .suspend = usbnet_suspend, | |
598 | .resume = usbnet_resume, | |
599 | }; | |
600 | ||
601 | static int __init rndis_init(void) | |
602 | { | |
603 | return usb_register(&rndis_driver); | |
604 | } | |
605 | module_init(rndis_init); | |
606 | ||
607 | static void __exit rndis_exit(void) | |
608 | { | |
609 | usb_deregister(&rndis_driver); | |
610 | } | |
611 | module_exit(rndis_exit); | |
612 | ||
613 | MODULE_AUTHOR("David Brownell"); | |
614 | MODULE_DESCRIPTION("USB Host side RNDIS driver"); | |
615 | MODULE_LICENSE("GPL"); |