• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Networking over Thunderbolt cable using Apple ThunderboltIP protocol
4  *
5  * Copyright (C) 2017, Intel Corporation
6  * Authors: Amir Levy <amir.jer.levy@intel.com>
7  *          Michael Jamet <michael.jamet@intel.com>
8  *          Mika Westerberg <mika.westerberg@linux.intel.com>
9  */
10 
11 #include <linux/atomic.h>
12 #include <linux/highmem.h>
13 #include <linux/if_vlan.h>
14 #include <linux/jhash.h>
15 #include <linux/module.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/sizes.h>
19 #include <linux/thunderbolt.h>
20 #include <linux/uuid.h>
21 #include <linux/workqueue.h>
22 
23 #include <net/ip6_checksum.h>
24 
25 /* Protocol timeouts in ms */
26 #define TBNET_LOGIN_DELAY	4500
27 #define TBNET_LOGIN_TIMEOUT	500
28 #define TBNET_LOGOUT_TIMEOUT	1000
29 
30 #define TBNET_RING_SIZE		256
31 #define TBNET_LOGIN_RETRIES	60
32 #define TBNET_LOGOUT_RETRIES	10
33 #define TBNET_MATCH_FRAGS_ID	BIT(1)
34 #define TBNET_64K_FRAMES	BIT(2)
35 #define TBNET_MAX_MTU		SZ_64K
36 #define TBNET_FRAME_SIZE	SZ_4K
37 #define TBNET_MAX_PAYLOAD_SIZE	\
38 	(TBNET_FRAME_SIZE - sizeof(struct thunderbolt_ip_frame_header))
39 /* Rx packets need to hold space for skb_shared_info */
40 #define TBNET_RX_MAX_SIZE	\
41 	(TBNET_FRAME_SIZE + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
42 #define TBNET_RX_PAGE_ORDER	get_order(TBNET_RX_MAX_SIZE)
43 #define TBNET_RX_PAGE_SIZE	(PAGE_SIZE << TBNET_RX_PAGE_ORDER)
44 
45 #define TBNET_L0_PORT_NUM(route) ((route) & GENMASK(5, 0))
46 
47 /**
48  * struct thunderbolt_ip_frame_header - Header for each Thunderbolt frame
49  * @frame_size: size of the data with the frame
50  * @frame_index: running index on the frames
51  * @frame_id: ID of the frame to match frames to specific packet
52  * @frame_count: how many frames assembles a full packet
53  *
54  * Each data frame passed to the high-speed DMA ring has this header. If
55  * the XDomain network directory announces that %TBNET_MATCH_FRAGS_ID is
56  * supported then @frame_id is filled, otherwise it stays %0.
57  */
58 struct thunderbolt_ip_frame_header {
59 	u32 frame_size;
60 	u16 frame_index;
61 	u16 frame_id;
62 	u32 frame_count;
63 };
64 
65 enum thunderbolt_ip_frame_pdf {
66 	TBIP_PDF_FRAME_START = 1,
67 	TBIP_PDF_FRAME_END,
68 };
69 
70 enum thunderbolt_ip_type {
71 	TBIP_LOGIN,
72 	TBIP_LOGIN_RESPONSE,
73 	TBIP_LOGOUT,
74 	TBIP_STATUS,
75 };
76 
77 struct thunderbolt_ip_header {
78 	u32 route_hi;
79 	u32 route_lo;
80 	u32 length_sn;
81 	uuid_t uuid;
82 	uuid_t initiator_uuid;
83 	uuid_t target_uuid;
84 	u32 type;
85 	u32 command_id;
86 };
87 
88 #define TBIP_HDR_LENGTH_MASK		GENMASK(5, 0)
89 #define TBIP_HDR_SN_MASK		GENMASK(28, 27)
90 #define TBIP_HDR_SN_SHIFT		27
91 
92 struct thunderbolt_ip_login {
93 	struct thunderbolt_ip_header hdr;
94 	u32 proto_version;
95 	u32 transmit_path;
96 	u32 reserved[4];
97 };
98 
99 #define TBIP_LOGIN_PROTO_VERSION	1
100 
101 struct thunderbolt_ip_login_response {
102 	struct thunderbolt_ip_header hdr;
103 	u32 status;
104 	u32 receiver_mac[2];
105 	u32 receiver_mac_len;
106 	u32 reserved[4];
107 };
108 
109 struct thunderbolt_ip_logout {
110 	struct thunderbolt_ip_header hdr;
111 };
112 
113 struct thunderbolt_ip_status {
114 	struct thunderbolt_ip_header hdr;
115 	u32 status;
116 };
117 
118 struct tbnet_stats {
119 	u64 tx_packets;
120 	u64 rx_packets;
121 	u64 tx_bytes;
122 	u64 rx_bytes;
123 	u64 rx_errors;
124 	u64 tx_errors;
125 	u64 rx_length_errors;
126 	u64 rx_over_errors;
127 	u64 rx_crc_errors;
128 	u64 rx_missed_errors;
129 };
130 
131 struct tbnet_frame {
132 	struct net_device *dev;
133 	struct page *page;
134 	struct ring_frame frame;
135 };
136 
137 struct tbnet_ring {
138 	struct tbnet_frame frames[TBNET_RING_SIZE];
139 	unsigned int cons;
140 	unsigned int prod;
141 	struct tb_ring *ring;
142 };
143 
144 /**
145  * struct tbnet - ThunderboltIP network driver private data
146  * @svc: XDomain service the driver is bound to
147  * @xd: XDomain the service blongs to
148  * @handler: ThunderboltIP configuration protocol handler
149  * @dev: Networking device
150  * @napi: NAPI structure for Rx polling
151  * @stats: Network statistics
152  * @skb: Network packet that is currently processed on Rx path
153  * @command_id: ID used for next configuration protocol packet
154  * @login_sent: ThunderboltIP login message successfully sent
155  * @login_received: ThunderboltIP login message received from the remote
156  *		    host
157  * @local_transmit_path: HopID we are using to send out packets
158  * @remote_transmit_path: HopID the other end is using to send packets to us
159  * @connection_lock: Lock serializing access to @login_sent,
160  *		     @login_received and @transmit_path.
161  * @login_retries: Number of login retries currently done
162  * @login_work: Worker to send ThunderboltIP login packets
163  * @connected_work: Worker that finalizes the ThunderboltIP connection
164  *		    setup and enables DMA paths for high speed data
165  *		    transfers
166  * @disconnect_work: Worker that handles tearing down the ThunderboltIP
167  *		     connection
168  * @rx_hdr: Copy of the currently processed Rx frame. Used when a
169  *	    network packet consists of multiple Thunderbolt frames.
170  *	    In host byte order.
171  * @rx_ring: Software ring holding Rx frames
172  * @frame_id: Frame ID use for next Tx packet
173  *            (if %TBNET_MATCH_FRAGS_ID is supported in both ends)
174  * @tx_ring: Software ring holding Tx frames
175  */
176 struct tbnet {
177 	const struct tb_service *svc;
178 	struct tb_xdomain *xd;
179 	struct tb_protocol_handler handler;
180 	struct net_device *dev;
181 	struct napi_struct napi;
182 	struct tbnet_stats stats;
183 	struct sk_buff *skb;
184 	atomic_t command_id;
185 	bool login_sent;
186 	bool login_received;
187 	int local_transmit_path;
188 	int remote_transmit_path;
189 	struct mutex connection_lock;
190 	int login_retries;
191 	struct delayed_work login_work;
192 	struct work_struct connected_work;
193 	struct work_struct disconnect_work;
194 	struct thunderbolt_ip_frame_header rx_hdr;
195 	struct tbnet_ring rx_ring;
196 	atomic_t frame_id;
197 	struct tbnet_ring tx_ring;
198 };
199 
200 /* Network property directory UUID: c66189ca-1cce-4195-bdb8-49592e5f5a4f */
201 static const uuid_t tbnet_dir_uuid =
202 	UUID_INIT(0xc66189ca, 0x1cce, 0x4195,
203 		  0xbd, 0xb8, 0x49, 0x59, 0x2e, 0x5f, 0x5a, 0x4f);
204 
205 /* ThunderboltIP protocol UUID: 798f589e-3616-8a47-97c6-5664a920c8dd */
206 static const uuid_t tbnet_svc_uuid =
207 	UUID_INIT(0x798f589e, 0x3616, 0x8a47,
208 		  0x97, 0xc6, 0x56, 0x64, 0xa9, 0x20, 0xc8, 0xdd);
209 
210 static struct tb_property_dir *tbnet_dir;
211 
tbnet_fill_header(struct thunderbolt_ip_header * hdr,u64 route,u8 sequence,const uuid_t * initiator_uuid,const uuid_t * target_uuid,enum thunderbolt_ip_type type,size_t size,u32 command_id)212 static void tbnet_fill_header(struct thunderbolt_ip_header *hdr, u64 route,
213 	u8 sequence, const uuid_t *initiator_uuid, const uuid_t *target_uuid,
214 	enum thunderbolt_ip_type type, size_t size, u32 command_id)
215 {
216 	u32 length_sn;
217 
218 	/* Length does not include route_hi/lo and length_sn fields */
219 	length_sn = (size - 3 * 4) / 4;
220 	length_sn |= (sequence << TBIP_HDR_SN_SHIFT) & TBIP_HDR_SN_MASK;
221 
222 	hdr->route_hi = upper_32_bits(route);
223 	hdr->route_lo = lower_32_bits(route);
224 	hdr->length_sn = length_sn;
225 	uuid_copy(&hdr->uuid, &tbnet_svc_uuid);
226 	uuid_copy(&hdr->initiator_uuid, initiator_uuid);
227 	uuid_copy(&hdr->target_uuid, target_uuid);
228 	hdr->type = type;
229 	hdr->command_id = command_id;
230 }
231 
tbnet_login_response(struct tbnet * net,u64 route,u8 sequence,u32 command_id)232 static int tbnet_login_response(struct tbnet *net, u64 route, u8 sequence,
233 				u32 command_id)
234 {
235 	struct thunderbolt_ip_login_response reply;
236 	struct tb_xdomain *xd = net->xd;
237 
238 	memset(&reply, 0, sizeof(reply));
239 	tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
240 			  xd->remote_uuid, TBIP_LOGIN_RESPONSE, sizeof(reply),
241 			  command_id);
242 	memcpy(reply.receiver_mac, net->dev->dev_addr, ETH_ALEN);
243 	reply.receiver_mac_len = ETH_ALEN;
244 
245 	return tb_xdomain_response(xd, &reply, sizeof(reply),
246 				   TB_CFG_PKG_XDOMAIN_RESP);
247 }
248 
tbnet_login_request(struct tbnet * net,u8 sequence)249 static int tbnet_login_request(struct tbnet *net, u8 sequence)
250 {
251 	struct thunderbolt_ip_login_response reply;
252 	struct thunderbolt_ip_login request;
253 	struct tb_xdomain *xd = net->xd;
254 
255 	memset(&request, 0, sizeof(request));
256 	tbnet_fill_header(&request.hdr, xd->route, sequence, xd->local_uuid,
257 			  xd->remote_uuid, TBIP_LOGIN, sizeof(request),
258 			  atomic_inc_return(&net->command_id));
259 
260 	request.proto_version = TBIP_LOGIN_PROTO_VERSION;
261 	request.transmit_path = net->local_transmit_path;
262 
263 	return tb_xdomain_request(xd, &request, sizeof(request),
264 				  TB_CFG_PKG_XDOMAIN_RESP, &reply,
265 				  sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
266 				  TBNET_LOGIN_TIMEOUT);
267 }
268 
tbnet_logout_response(struct tbnet * net,u64 route,u8 sequence,u32 command_id)269 static int tbnet_logout_response(struct tbnet *net, u64 route, u8 sequence,
270 				 u32 command_id)
271 {
272 	struct thunderbolt_ip_status reply;
273 	struct tb_xdomain *xd = net->xd;
274 
275 	memset(&reply, 0, sizeof(reply));
276 	tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
277 			  xd->remote_uuid, TBIP_STATUS, sizeof(reply),
278 			  atomic_inc_return(&net->command_id));
279 	return tb_xdomain_response(xd, &reply, sizeof(reply),
280 				   TB_CFG_PKG_XDOMAIN_RESP);
281 }
282 
tbnet_logout_request(struct tbnet * net)283 static int tbnet_logout_request(struct tbnet *net)
284 {
285 	struct thunderbolt_ip_logout request;
286 	struct thunderbolt_ip_status reply;
287 	struct tb_xdomain *xd = net->xd;
288 
289 	memset(&request, 0, sizeof(request));
290 	tbnet_fill_header(&request.hdr, xd->route, 0, xd->local_uuid,
291 			  xd->remote_uuid, TBIP_LOGOUT, sizeof(request),
292 			  atomic_inc_return(&net->command_id));
293 
294 	return tb_xdomain_request(xd, &request, sizeof(request),
295 				  TB_CFG_PKG_XDOMAIN_RESP, &reply,
296 				  sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
297 				  TBNET_LOGOUT_TIMEOUT);
298 }
299 
start_login(struct tbnet * net)300 static void start_login(struct tbnet *net)
301 {
302 	mutex_lock(&net->connection_lock);
303 	net->login_sent = false;
304 	net->login_received = false;
305 	mutex_unlock(&net->connection_lock);
306 
307 	queue_delayed_work(system_long_wq, &net->login_work,
308 			   msecs_to_jiffies(1000));
309 }
310 
stop_login(struct tbnet * net)311 static void stop_login(struct tbnet *net)
312 {
313 	cancel_delayed_work_sync(&net->login_work);
314 	cancel_work_sync(&net->connected_work);
315 }
316 
tbnet_frame_size(const struct tbnet_frame * tf)317 static inline unsigned int tbnet_frame_size(const struct tbnet_frame *tf)
318 {
319 	return tf->frame.size ? : TBNET_FRAME_SIZE;
320 }
321 
tbnet_free_buffers(struct tbnet_ring * ring)322 static void tbnet_free_buffers(struct tbnet_ring *ring)
323 {
324 	unsigned int i;
325 
326 	for (i = 0; i < TBNET_RING_SIZE; i++) {
327 		struct device *dma_dev = tb_ring_dma_device(ring->ring);
328 		struct tbnet_frame *tf = &ring->frames[i];
329 		enum dma_data_direction dir;
330 		unsigned int order;
331 		size_t size;
332 
333 		if (!tf->page)
334 			continue;
335 
336 		if (ring->ring->is_tx) {
337 			dir = DMA_TO_DEVICE;
338 			order = 0;
339 			size = TBNET_FRAME_SIZE;
340 		} else {
341 			dir = DMA_FROM_DEVICE;
342 			order = TBNET_RX_PAGE_ORDER;
343 			size = TBNET_RX_PAGE_SIZE;
344 		}
345 
346 		if (tf->frame.buffer_phy)
347 			dma_unmap_page(dma_dev, tf->frame.buffer_phy, size,
348 				       dir);
349 
350 		__free_pages(tf->page, order);
351 		tf->page = NULL;
352 	}
353 
354 	ring->cons = 0;
355 	ring->prod = 0;
356 }
357 
tbnet_tear_down(struct tbnet * net,bool send_logout)358 static void tbnet_tear_down(struct tbnet *net, bool send_logout)
359 {
360 	netif_carrier_off(net->dev);
361 	netif_stop_queue(net->dev);
362 
363 	stop_login(net);
364 
365 	mutex_lock(&net->connection_lock);
366 
367 	if (net->login_sent && net->login_received) {
368 		int ret, retries = TBNET_LOGOUT_RETRIES;
369 
370 		while (send_logout && retries-- > 0) {
371 			ret = tbnet_logout_request(net);
372 			if (ret != -ETIMEDOUT)
373 				break;
374 		}
375 
376 		tb_ring_stop(net->rx_ring.ring);
377 		tb_ring_stop(net->tx_ring.ring);
378 		tbnet_free_buffers(&net->rx_ring);
379 		tbnet_free_buffers(&net->tx_ring);
380 
381 		ret = tb_xdomain_disable_paths(net->xd,
382 					       net->local_transmit_path,
383 					       net->rx_ring.ring->hop,
384 					       net->remote_transmit_path,
385 					       net->tx_ring.ring->hop);
386 		if (ret)
387 			netdev_warn(net->dev, "failed to disable DMA paths\n");
388 
389 		tb_xdomain_release_in_hopid(net->xd, net->remote_transmit_path);
390 		net->remote_transmit_path = 0;
391 	}
392 
393 	net->login_retries = 0;
394 	net->login_sent = false;
395 	net->login_received = false;
396 
397 	mutex_unlock(&net->connection_lock);
398 }
399 
tbnet_handle_packet(const void * buf,size_t size,void * data)400 static int tbnet_handle_packet(const void *buf, size_t size, void *data)
401 {
402 	const struct thunderbolt_ip_login *pkg = buf;
403 	struct tbnet *net = data;
404 	u32 command_id;
405 	int ret = 0;
406 	u32 sequence;
407 	u64 route;
408 
409 	/* Make sure the packet is for us */
410 	if (size < sizeof(struct thunderbolt_ip_header))
411 		return 0;
412 	if (!uuid_equal(&pkg->hdr.initiator_uuid, net->xd->remote_uuid))
413 		return 0;
414 	if (!uuid_equal(&pkg->hdr.target_uuid, net->xd->local_uuid))
415 		return 0;
416 
417 	route = ((u64)pkg->hdr.route_hi << 32) | pkg->hdr.route_lo;
418 	route &= ~BIT_ULL(63);
419 	if (route != net->xd->route)
420 		return 0;
421 
422 	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
423 	sequence >>= TBIP_HDR_SN_SHIFT;
424 	command_id = pkg->hdr.command_id;
425 
426 	switch (pkg->hdr.type) {
427 	case TBIP_LOGIN:
428 		if (!netif_running(net->dev))
429 			break;
430 
431 		ret = tbnet_login_response(net, route, sequence,
432 					   pkg->hdr.command_id);
433 		if (!ret) {
434 			mutex_lock(&net->connection_lock);
435 			net->login_received = true;
436 			net->remote_transmit_path = pkg->transmit_path;
437 
438 			/* If we reached the number of max retries or
439 			 * previous logout, schedule another round of
440 			 * login retries
441 			 */
442 			if (net->login_retries >= TBNET_LOGIN_RETRIES ||
443 			    !net->login_sent) {
444 				net->login_retries = 0;
445 				queue_delayed_work(system_long_wq,
446 						   &net->login_work, 0);
447 			}
448 			mutex_unlock(&net->connection_lock);
449 
450 			queue_work(system_long_wq, &net->connected_work);
451 		}
452 		break;
453 
454 	case TBIP_LOGOUT:
455 		ret = tbnet_logout_response(net, route, sequence, command_id);
456 		if (!ret)
457 			queue_work(system_long_wq, &net->disconnect_work);
458 		break;
459 
460 	default:
461 		return 0;
462 	}
463 
464 	if (ret)
465 		netdev_warn(net->dev, "failed to send ThunderboltIP response\n");
466 
467 	return 1;
468 }
469 
tbnet_available_buffers(const struct tbnet_ring * ring)470 static unsigned int tbnet_available_buffers(const struct tbnet_ring *ring)
471 {
472 	return ring->prod - ring->cons;
473 }
474 
tbnet_alloc_rx_buffers(struct tbnet * net,unsigned int nbuffers)475 static int tbnet_alloc_rx_buffers(struct tbnet *net, unsigned int nbuffers)
476 {
477 	struct tbnet_ring *ring = &net->rx_ring;
478 	int ret;
479 
480 	while (nbuffers--) {
481 		struct device *dma_dev = tb_ring_dma_device(ring->ring);
482 		unsigned int index = ring->prod & (TBNET_RING_SIZE - 1);
483 		struct tbnet_frame *tf = &ring->frames[index];
484 		dma_addr_t dma_addr;
485 
486 		if (tf->page)
487 			break;
488 
489 		/* Allocate page (order > 0) so that it can hold maximum
490 		 * ThunderboltIP frame (4kB) and the additional room for
491 		 * SKB shared info required by build_skb().
492 		 */
493 		tf->page = dev_alloc_pages(TBNET_RX_PAGE_ORDER);
494 		if (!tf->page) {
495 			ret = -ENOMEM;
496 			goto err_free;
497 		}
498 
499 		dma_addr = dma_map_page(dma_dev, tf->page, 0,
500 					TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
501 		if (dma_mapping_error(dma_dev, dma_addr)) {
502 			ret = -ENOMEM;
503 			goto err_free;
504 		}
505 
506 		tf->frame.buffer_phy = dma_addr;
507 		tf->dev = net->dev;
508 
509 		tb_ring_rx(ring->ring, &tf->frame);
510 
511 		ring->prod++;
512 	}
513 
514 	return 0;
515 
516 err_free:
517 	tbnet_free_buffers(ring);
518 	return ret;
519 }
520 
tbnet_get_tx_buffer(struct tbnet * net)521 static struct tbnet_frame *tbnet_get_tx_buffer(struct tbnet *net)
522 {
523 	struct tbnet_ring *ring = &net->tx_ring;
524 	struct device *dma_dev = tb_ring_dma_device(ring->ring);
525 	struct tbnet_frame *tf;
526 	unsigned int index;
527 
528 	if (!tbnet_available_buffers(ring))
529 		return NULL;
530 
531 	index = ring->cons++ & (TBNET_RING_SIZE - 1);
532 
533 	tf = &ring->frames[index];
534 	tf->frame.size = 0;
535 
536 	dma_sync_single_for_cpu(dma_dev, tf->frame.buffer_phy,
537 				tbnet_frame_size(tf), DMA_TO_DEVICE);
538 
539 	return tf;
540 }
541 
tbnet_tx_callback(struct tb_ring * ring,struct ring_frame * frame,bool canceled)542 static void tbnet_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
543 			      bool canceled)
544 {
545 	struct tbnet_frame *tf = container_of(frame, typeof(*tf), frame);
546 	struct tbnet *net = netdev_priv(tf->dev);
547 
548 	/* Return buffer to the ring */
549 	net->tx_ring.prod++;
550 
551 	if (tbnet_available_buffers(&net->tx_ring) >= TBNET_RING_SIZE / 2)
552 		netif_wake_queue(net->dev);
553 }
554 
tbnet_alloc_tx_buffers(struct tbnet * net)555 static int tbnet_alloc_tx_buffers(struct tbnet *net)
556 {
557 	struct tbnet_ring *ring = &net->tx_ring;
558 	struct device *dma_dev = tb_ring_dma_device(ring->ring);
559 	unsigned int i;
560 
561 	for (i = 0; i < TBNET_RING_SIZE; i++) {
562 		struct tbnet_frame *tf = &ring->frames[i];
563 		dma_addr_t dma_addr;
564 
565 		tf->page = alloc_page(GFP_KERNEL);
566 		if (!tf->page) {
567 			tbnet_free_buffers(ring);
568 			return -ENOMEM;
569 		}
570 
571 		dma_addr = dma_map_page(dma_dev, tf->page, 0, TBNET_FRAME_SIZE,
572 					DMA_TO_DEVICE);
573 		if (dma_mapping_error(dma_dev, dma_addr)) {
574 			__free_page(tf->page);
575 			tf->page = NULL;
576 			tbnet_free_buffers(ring);
577 			return -ENOMEM;
578 		}
579 
580 		tf->dev = net->dev;
581 		tf->frame.buffer_phy = dma_addr;
582 		tf->frame.callback = tbnet_tx_callback;
583 		tf->frame.sof = TBIP_PDF_FRAME_START;
584 		tf->frame.eof = TBIP_PDF_FRAME_END;
585 	}
586 
587 	ring->cons = 0;
588 	ring->prod = TBNET_RING_SIZE - 1;
589 
590 	return 0;
591 }
592 
tbnet_connected_work(struct work_struct * work)593 static void tbnet_connected_work(struct work_struct *work)
594 {
595 	struct tbnet *net = container_of(work, typeof(*net), connected_work);
596 	bool connected;
597 	int ret;
598 
599 	if (netif_carrier_ok(net->dev))
600 		return;
601 
602 	mutex_lock(&net->connection_lock);
603 	connected = net->login_sent && net->login_received;
604 	mutex_unlock(&net->connection_lock);
605 
606 	if (!connected)
607 		return;
608 
609 	ret = tb_xdomain_alloc_in_hopid(net->xd, net->remote_transmit_path);
610 	if (ret != net->remote_transmit_path) {
611 		netdev_err(net->dev, "failed to allocate Rx HopID\n");
612 		return;
613 	}
614 
615 	/* Both logins successful so enable the rings, high-speed DMA
616 	 * paths and start the network device queue.
617 	 *
618 	 * Note we enable the DMA paths last to make sure we have primed
619 	 * the Rx ring before any incoming packets are allowed to
620 	 * arrive.
621 	 */
622 	tb_ring_start(net->tx_ring.ring);
623 	tb_ring_start(net->rx_ring.ring);
624 
625 	ret = tbnet_alloc_rx_buffers(net, TBNET_RING_SIZE);
626 	if (ret)
627 		goto err_stop_rings;
628 
629 	ret = tbnet_alloc_tx_buffers(net);
630 	if (ret)
631 		goto err_free_rx_buffers;
632 
633 	ret = tb_xdomain_enable_paths(net->xd, net->local_transmit_path,
634 				      net->rx_ring.ring->hop,
635 				      net->remote_transmit_path,
636 				      net->tx_ring.ring->hop);
637 	if (ret) {
638 		netdev_err(net->dev, "failed to enable DMA paths\n");
639 		goto err_free_tx_buffers;
640 	}
641 
642 	netif_carrier_on(net->dev);
643 	netif_start_queue(net->dev);
644 	return;
645 
646 err_free_tx_buffers:
647 	tbnet_free_buffers(&net->tx_ring);
648 err_free_rx_buffers:
649 	tbnet_free_buffers(&net->rx_ring);
650 err_stop_rings:
651 	tb_ring_stop(net->rx_ring.ring);
652 	tb_ring_stop(net->tx_ring.ring);
653 	tb_xdomain_release_in_hopid(net->xd, net->remote_transmit_path);
654 }
655 
tbnet_login_work(struct work_struct * work)656 static void tbnet_login_work(struct work_struct *work)
657 {
658 	struct tbnet *net = container_of(work, typeof(*net), login_work.work);
659 	unsigned long delay = msecs_to_jiffies(TBNET_LOGIN_DELAY);
660 	int ret;
661 
662 	if (netif_carrier_ok(net->dev))
663 		return;
664 
665 	ret = tbnet_login_request(net, net->login_retries % 4);
666 	if (ret) {
667 		if (net->login_retries++ < TBNET_LOGIN_RETRIES) {
668 			queue_delayed_work(system_long_wq, &net->login_work,
669 					   delay);
670 		} else {
671 			netdev_info(net->dev, "ThunderboltIP login timed out\n");
672 		}
673 	} else {
674 		net->login_retries = 0;
675 
676 		mutex_lock(&net->connection_lock);
677 		net->login_sent = true;
678 		mutex_unlock(&net->connection_lock);
679 
680 		queue_work(system_long_wq, &net->connected_work);
681 	}
682 }
683 
tbnet_disconnect_work(struct work_struct * work)684 static void tbnet_disconnect_work(struct work_struct *work)
685 {
686 	struct tbnet *net = container_of(work, typeof(*net), disconnect_work);
687 
688 	tbnet_tear_down(net, false);
689 }
690 
tbnet_check_frame(struct tbnet * net,const struct tbnet_frame * tf,const struct thunderbolt_ip_frame_header * hdr)691 static bool tbnet_check_frame(struct tbnet *net, const struct tbnet_frame *tf,
692 			      const struct thunderbolt_ip_frame_header *hdr)
693 {
694 	u32 frame_id, frame_count, frame_size, frame_index;
695 	unsigned int size;
696 
697 	if (tf->frame.flags & RING_DESC_CRC_ERROR) {
698 		net->stats.rx_crc_errors++;
699 		return false;
700 	} else if (tf->frame.flags & RING_DESC_BUFFER_OVERRUN) {
701 		net->stats.rx_over_errors++;
702 		return false;
703 	}
704 
705 	/* Should be greater than just header i.e. contains data */
706 	size = tbnet_frame_size(tf);
707 	if (size <= sizeof(*hdr)) {
708 		net->stats.rx_length_errors++;
709 		return false;
710 	}
711 
712 	frame_count = le32_to_cpu(hdr->frame_count);
713 	frame_size = le32_to_cpu(hdr->frame_size);
714 	frame_index = le16_to_cpu(hdr->frame_index);
715 	frame_id = le16_to_cpu(hdr->frame_id);
716 
717 	if ((frame_size > size - sizeof(*hdr)) || !frame_size) {
718 		net->stats.rx_length_errors++;
719 		return false;
720 	}
721 
722 	/* In case we're in the middle of packet, validate the frame
723 	 * header based on first fragment of the packet.
724 	 */
725 	if (net->skb && net->rx_hdr.frame_count) {
726 		/* Check the frame count fits the count field */
727 		if (frame_count != net->rx_hdr.frame_count) {
728 			net->stats.rx_length_errors++;
729 			return false;
730 		}
731 
732 		/* Check the frame identifiers are incremented correctly,
733 		 * and id is matching.
734 		 */
735 		if (frame_index != net->rx_hdr.frame_index + 1 ||
736 		    frame_id != net->rx_hdr.frame_id) {
737 			net->stats.rx_missed_errors++;
738 			return false;
739 		}
740 
741 		if (net->skb->len + frame_size > TBNET_MAX_MTU) {
742 			net->stats.rx_length_errors++;
743 			return false;
744 		}
745 
746 		return true;
747 	}
748 
749 	/* Start of packet, validate the frame header */
750 	if (frame_count == 0 || frame_count > TBNET_RING_SIZE / 4) {
751 		net->stats.rx_length_errors++;
752 		return false;
753 	}
754 	if (frame_index != 0) {
755 		net->stats.rx_missed_errors++;
756 		return false;
757 	}
758 
759 	return true;
760 }
761 
tbnet_poll(struct napi_struct * napi,int budget)762 static int tbnet_poll(struct napi_struct *napi, int budget)
763 {
764 	struct tbnet *net = container_of(napi, struct tbnet, napi);
765 	unsigned int cleaned_count = tbnet_available_buffers(&net->rx_ring);
766 	struct device *dma_dev = tb_ring_dma_device(net->rx_ring.ring);
767 	unsigned int rx_packets = 0;
768 
769 	while (rx_packets < budget) {
770 		const struct thunderbolt_ip_frame_header *hdr;
771 		unsigned int hdr_size = sizeof(*hdr);
772 		struct sk_buff *skb = NULL;
773 		struct ring_frame *frame;
774 		struct tbnet_frame *tf;
775 		struct page *page;
776 		bool last = true;
777 		u32 frame_size;
778 
779 		/* Return some buffers to hardware, one at a time is too
780 		 * slow so allocate MAX_SKB_FRAGS buffers at the same
781 		 * time.
782 		 */
783 		if (cleaned_count >= MAX_SKB_FRAGS) {
784 			tbnet_alloc_rx_buffers(net, cleaned_count);
785 			cleaned_count = 0;
786 		}
787 
788 		frame = tb_ring_poll(net->rx_ring.ring);
789 		if (!frame)
790 			break;
791 
792 		dma_unmap_page(dma_dev, frame->buffer_phy,
793 			       TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
794 
795 		tf = container_of(frame, typeof(*tf), frame);
796 
797 		page = tf->page;
798 		tf->page = NULL;
799 		net->rx_ring.cons++;
800 		cleaned_count++;
801 
802 		hdr = page_address(page);
803 		if (!tbnet_check_frame(net, tf, hdr)) {
804 			__free_pages(page, TBNET_RX_PAGE_ORDER);
805 			dev_kfree_skb_any(net->skb);
806 			net->skb = NULL;
807 			continue;
808 		}
809 
810 		frame_size = le32_to_cpu(hdr->frame_size);
811 
812 		skb = net->skb;
813 		if (!skb) {
814 			skb = build_skb(page_address(page),
815 					TBNET_RX_PAGE_SIZE);
816 			if (!skb) {
817 				__free_pages(page, TBNET_RX_PAGE_ORDER);
818 				net->stats.rx_errors++;
819 				break;
820 			}
821 
822 			skb_reserve(skb, hdr_size);
823 			skb_put(skb, frame_size);
824 
825 			net->skb = skb;
826 		} else {
827 			skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
828 					page, hdr_size, frame_size,
829 					TBNET_RX_PAGE_SIZE - hdr_size);
830 		}
831 
832 		net->rx_hdr.frame_size = frame_size;
833 		net->rx_hdr.frame_count = le32_to_cpu(hdr->frame_count);
834 		net->rx_hdr.frame_index = le16_to_cpu(hdr->frame_index);
835 		net->rx_hdr.frame_id = le16_to_cpu(hdr->frame_id);
836 		last = net->rx_hdr.frame_index == net->rx_hdr.frame_count - 1;
837 
838 		rx_packets++;
839 		net->stats.rx_bytes += frame_size;
840 
841 		if (last) {
842 			skb->protocol = eth_type_trans(skb, net->dev);
843 			napi_gro_receive(&net->napi, skb);
844 			net->skb = NULL;
845 		}
846 	}
847 
848 	net->stats.rx_packets += rx_packets;
849 
850 	if (cleaned_count)
851 		tbnet_alloc_rx_buffers(net, cleaned_count);
852 
853 	if (rx_packets >= budget)
854 		return budget;
855 
856 	napi_complete_done(napi, rx_packets);
857 	/* Re-enable the ring interrupt */
858 	tb_ring_poll_complete(net->rx_ring.ring);
859 
860 	return rx_packets;
861 }
862 
tbnet_start_poll(void * data)863 static void tbnet_start_poll(void *data)
864 {
865 	struct tbnet *net = data;
866 
867 	napi_schedule(&net->napi);
868 }
869 
tbnet_open(struct net_device * dev)870 static int tbnet_open(struct net_device *dev)
871 {
872 	struct tbnet *net = netdev_priv(dev);
873 	struct tb_xdomain *xd = net->xd;
874 	u16 sof_mask, eof_mask;
875 	struct tb_ring *ring;
876 	int hopid;
877 
878 	netif_carrier_off(dev);
879 
880 	ring = tb_ring_alloc_tx(xd->tb->nhi, -1, TBNET_RING_SIZE,
881 				RING_FLAG_FRAME);
882 	if (!ring) {
883 		netdev_err(dev, "failed to allocate Tx ring\n");
884 		return -ENOMEM;
885 	}
886 	net->tx_ring.ring = ring;
887 
888 	hopid = tb_xdomain_alloc_out_hopid(xd, -1);
889 	if (hopid < 0) {
890 		netdev_err(dev, "failed to allocate Tx HopID\n");
891 		tb_ring_free(net->tx_ring.ring);
892 		net->tx_ring.ring = NULL;
893 		return hopid;
894 	}
895 	net->local_transmit_path = hopid;
896 
897 	sof_mask = BIT(TBIP_PDF_FRAME_START);
898 	eof_mask = BIT(TBIP_PDF_FRAME_END);
899 
900 	ring = tb_ring_alloc_rx(xd->tb->nhi, -1, TBNET_RING_SIZE,
901 				RING_FLAG_FRAME, 0, sof_mask, eof_mask,
902 				tbnet_start_poll, net);
903 	if (!ring) {
904 		netdev_err(dev, "failed to allocate Rx ring\n");
905 		tb_xdomain_release_out_hopid(xd, hopid);
906 		tb_ring_free(net->tx_ring.ring);
907 		net->tx_ring.ring = NULL;
908 		return -ENOMEM;
909 	}
910 	net->rx_ring.ring = ring;
911 
912 	napi_enable(&net->napi);
913 	start_login(net);
914 
915 	return 0;
916 }
917 
tbnet_stop(struct net_device * dev)918 static int tbnet_stop(struct net_device *dev)
919 {
920 	struct tbnet *net = netdev_priv(dev);
921 
922 	napi_disable(&net->napi);
923 
924 	cancel_work_sync(&net->disconnect_work);
925 	tbnet_tear_down(net, true);
926 
927 	tb_ring_free(net->rx_ring.ring);
928 	net->rx_ring.ring = NULL;
929 
930 	tb_xdomain_release_out_hopid(net->xd, net->local_transmit_path);
931 	tb_ring_free(net->tx_ring.ring);
932 	net->tx_ring.ring = NULL;
933 
934 	return 0;
935 }
936 
tbnet_xmit_csum_and_map(struct tbnet * net,struct sk_buff * skb,struct tbnet_frame ** frames,u32 frame_count)937 static bool tbnet_xmit_csum_and_map(struct tbnet *net, struct sk_buff *skb,
938 	struct tbnet_frame **frames, u32 frame_count)
939 {
940 	struct thunderbolt_ip_frame_header *hdr = page_address(frames[0]->page);
941 	struct device *dma_dev = tb_ring_dma_device(net->tx_ring.ring);
942 	__wsum wsum = htonl(skb->len - skb_transport_offset(skb));
943 	unsigned int i, len, offset = skb_transport_offset(skb);
944 	__be16 protocol = skb->protocol;
945 	void *data = skb->data;
946 	void *dest = hdr + 1;
947 	__sum16 *tucso;
948 
949 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
950 		/* No need to calculate checksum so we just update the
951 		 * total frame count and sync the frames for DMA.
952 		 */
953 		for (i = 0; i < frame_count; i++) {
954 			hdr = page_address(frames[i]->page);
955 			hdr->frame_count = cpu_to_le32(frame_count);
956 			dma_sync_single_for_device(dma_dev,
957 				frames[i]->frame.buffer_phy,
958 				tbnet_frame_size(frames[i]), DMA_TO_DEVICE);
959 		}
960 
961 		return true;
962 	}
963 
964 	if (protocol == htons(ETH_P_8021Q)) {
965 		struct vlan_hdr *vhdr, vh;
966 
967 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(vh), &vh);
968 		if (!vhdr)
969 			return false;
970 
971 		protocol = vhdr->h_vlan_encapsulated_proto;
972 	}
973 
974 	/* Data points on the beginning of packet.
975 	 * Check is the checksum absolute place in the packet.
976 	 * ipcso will update IP checksum.
977 	 * tucso will update TCP/UPD checksum.
978 	 */
979 	if (protocol == htons(ETH_P_IP)) {
980 		__sum16 *ipcso = dest + ((void *)&(ip_hdr(skb)->check) - data);
981 
982 		*ipcso = 0;
983 		*ipcso = ip_fast_csum(dest + skb_network_offset(skb),
984 				      ip_hdr(skb)->ihl);
985 
986 		if (ip_hdr(skb)->protocol == IPPROTO_TCP)
987 			tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
988 		else if (ip_hdr(skb)->protocol == IPPROTO_UDP)
989 			tucso = dest + ((void *)&(udp_hdr(skb)->check) - data);
990 		else
991 			return false;
992 
993 		*tucso = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
994 					    ip_hdr(skb)->daddr, 0,
995 					    ip_hdr(skb)->protocol, 0);
996 	} else if (skb_is_gso(skb) && skb_is_gso_v6(skb)) {
997 		tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
998 		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
999 					  &ipv6_hdr(skb)->daddr, 0,
1000 					  IPPROTO_TCP, 0);
1001 	} else if (protocol == htons(ETH_P_IPV6)) {
1002 		tucso = dest + skb_checksum_start_offset(skb) + skb->csum_offset;
1003 		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
1004 					  &ipv6_hdr(skb)->daddr, 0,
1005 					  ipv6_hdr(skb)->nexthdr, 0);
1006 	} else {
1007 		return false;
1008 	}
1009 
1010 	/* First frame was headers, rest of the frames contain data.
1011 	 * Calculate checksum over each frame.
1012 	 */
1013 	for (i = 0; i < frame_count; i++) {
1014 		hdr = page_address(frames[i]->page);
1015 		dest = (void *)(hdr + 1) + offset;
1016 		len = le32_to_cpu(hdr->frame_size) - offset;
1017 		wsum = csum_partial(dest, len, wsum);
1018 		hdr->frame_count = cpu_to_le32(frame_count);
1019 
1020 		offset = 0;
1021 	}
1022 
1023 	*tucso = csum_fold(wsum);
1024 
1025 	/* Checksum is finally calculated and we don't touch the memory
1026 	 * anymore, so DMA sync the frames now.
1027 	 */
1028 	for (i = 0; i < frame_count; i++) {
1029 		dma_sync_single_for_device(dma_dev, frames[i]->frame.buffer_phy,
1030 			tbnet_frame_size(frames[i]), DMA_TO_DEVICE);
1031 	}
1032 
1033 	return true;
1034 }
1035 
tbnet_kmap_frag(struct sk_buff * skb,unsigned int frag_num,unsigned int * len)1036 static void *tbnet_kmap_frag(struct sk_buff *skb, unsigned int frag_num,
1037 			     unsigned int *len)
1038 {
1039 	const skb_frag_t *frag = &skb_shinfo(skb)->frags[frag_num];
1040 
1041 	*len = skb_frag_size(frag);
1042 	return kmap_atomic(skb_frag_page(frag)) + skb_frag_off(frag);
1043 }
1044 
tbnet_start_xmit(struct sk_buff * skb,struct net_device * dev)1045 static netdev_tx_t tbnet_start_xmit(struct sk_buff *skb,
1046 				    struct net_device *dev)
1047 {
1048 	struct tbnet *net = netdev_priv(dev);
1049 	struct tbnet_frame *frames[MAX_SKB_FRAGS];
1050 	u16 frame_id = atomic_read(&net->frame_id);
1051 	struct thunderbolt_ip_frame_header *hdr;
1052 	unsigned int len = skb_headlen(skb);
1053 	unsigned int data_len = skb->len;
1054 	unsigned int nframes, i;
1055 	unsigned int frag = 0;
1056 	void *src = skb->data;
1057 	u32 frame_index = 0;
1058 	bool unmap = false;
1059 	void *dest;
1060 
1061 	nframes = DIV_ROUND_UP(data_len, TBNET_MAX_PAYLOAD_SIZE);
1062 	if (tbnet_available_buffers(&net->tx_ring) < nframes) {
1063 		netif_stop_queue(net->dev);
1064 		return NETDEV_TX_BUSY;
1065 	}
1066 
1067 	frames[frame_index] = tbnet_get_tx_buffer(net);
1068 	if (!frames[frame_index])
1069 		goto err_drop;
1070 
1071 	hdr = page_address(frames[frame_index]->page);
1072 	dest = hdr + 1;
1073 
1074 	/* If overall packet is bigger than the frame data size */
1075 	while (data_len > TBNET_MAX_PAYLOAD_SIZE) {
1076 		unsigned int size_left = TBNET_MAX_PAYLOAD_SIZE;
1077 
1078 		hdr->frame_size = cpu_to_le32(TBNET_MAX_PAYLOAD_SIZE);
1079 		hdr->frame_index = cpu_to_le16(frame_index);
1080 		hdr->frame_id = cpu_to_le16(frame_id);
1081 
1082 		do {
1083 			if (len > size_left) {
1084 				/* Copy data onto Tx buffer data with
1085 				 * full frame size then break and go to
1086 				 * next frame
1087 				 */
1088 				memcpy(dest, src, size_left);
1089 				len -= size_left;
1090 				dest += size_left;
1091 				src += size_left;
1092 				break;
1093 			}
1094 
1095 			memcpy(dest, src, len);
1096 			size_left -= len;
1097 			dest += len;
1098 
1099 			if (unmap) {
1100 				kunmap_atomic(src);
1101 				unmap = false;
1102 			}
1103 
1104 			/* Ensure all fragments have been processed */
1105 			if (frag < skb_shinfo(skb)->nr_frags) {
1106 				/* Map and then unmap quickly */
1107 				src = tbnet_kmap_frag(skb, frag++, &len);
1108 				unmap = true;
1109 			} else if (unlikely(size_left > 0)) {
1110 				goto err_drop;
1111 			}
1112 		} while (size_left > 0);
1113 
1114 		data_len -= TBNET_MAX_PAYLOAD_SIZE;
1115 		frame_index++;
1116 
1117 		frames[frame_index] = tbnet_get_tx_buffer(net);
1118 		if (!frames[frame_index])
1119 			goto err_drop;
1120 
1121 		hdr = page_address(frames[frame_index]->page);
1122 		dest = hdr + 1;
1123 	}
1124 
1125 	hdr->frame_size = cpu_to_le32(data_len);
1126 	hdr->frame_index = cpu_to_le16(frame_index);
1127 	hdr->frame_id = cpu_to_le16(frame_id);
1128 
1129 	frames[frame_index]->frame.size = data_len + sizeof(*hdr);
1130 
1131 	/* In case the remaining data_len is smaller than a frame */
1132 	while (len < data_len) {
1133 		memcpy(dest, src, len);
1134 		data_len -= len;
1135 		dest += len;
1136 
1137 		if (unmap) {
1138 			kunmap_atomic(src);
1139 			unmap = false;
1140 		}
1141 
1142 		if (frag < skb_shinfo(skb)->nr_frags) {
1143 			src = tbnet_kmap_frag(skb, frag++, &len);
1144 			unmap = true;
1145 		} else if (unlikely(data_len > 0)) {
1146 			goto err_drop;
1147 		}
1148 	}
1149 
1150 	memcpy(dest, src, data_len);
1151 
1152 	if (unmap)
1153 		kunmap_atomic(src);
1154 
1155 	if (!tbnet_xmit_csum_and_map(net, skb, frames, frame_index + 1))
1156 		goto err_drop;
1157 
1158 	for (i = 0; i < frame_index + 1; i++)
1159 		tb_ring_tx(net->tx_ring.ring, &frames[i]->frame);
1160 
1161 	if (net->svc->prtcstns & TBNET_MATCH_FRAGS_ID)
1162 		atomic_inc(&net->frame_id);
1163 
1164 	net->stats.tx_packets++;
1165 	net->stats.tx_bytes += skb->len;
1166 
1167 	dev_consume_skb_any(skb);
1168 
1169 	return NETDEV_TX_OK;
1170 
1171 err_drop:
1172 	/* We can re-use the buffers */
1173 	net->tx_ring.cons -= frame_index;
1174 
1175 	dev_kfree_skb_any(skb);
1176 	net->stats.tx_errors++;
1177 
1178 	return NETDEV_TX_OK;
1179 }
1180 
tbnet_get_stats64(struct net_device * dev,struct rtnl_link_stats64 * stats)1181 static void tbnet_get_stats64(struct net_device *dev,
1182 			      struct rtnl_link_stats64 *stats)
1183 {
1184 	struct tbnet *net = netdev_priv(dev);
1185 
1186 	stats->tx_packets = net->stats.tx_packets;
1187 	stats->rx_packets = net->stats.rx_packets;
1188 	stats->tx_bytes = net->stats.tx_bytes;
1189 	stats->rx_bytes = net->stats.rx_bytes;
1190 	stats->rx_errors = net->stats.rx_errors + net->stats.rx_length_errors +
1191 		net->stats.rx_over_errors + net->stats.rx_crc_errors +
1192 		net->stats.rx_missed_errors;
1193 	stats->tx_errors = net->stats.tx_errors;
1194 	stats->rx_length_errors = net->stats.rx_length_errors;
1195 	stats->rx_over_errors = net->stats.rx_over_errors;
1196 	stats->rx_crc_errors = net->stats.rx_crc_errors;
1197 	stats->rx_missed_errors = net->stats.rx_missed_errors;
1198 }
1199 
1200 static const struct net_device_ops tbnet_netdev_ops = {
1201 	.ndo_open = tbnet_open,
1202 	.ndo_stop = tbnet_stop,
1203 	.ndo_start_xmit = tbnet_start_xmit,
1204 	.ndo_get_stats64 = tbnet_get_stats64,
1205 };
1206 
tbnet_generate_mac(struct net_device * dev)1207 static void tbnet_generate_mac(struct net_device *dev)
1208 {
1209 	const struct tbnet *net = netdev_priv(dev);
1210 	const struct tb_xdomain *xd = net->xd;
1211 	u8 phy_port;
1212 	u32 hash;
1213 
1214 	phy_port = tb_phy_port_from_link(TBNET_L0_PORT_NUM(xd->route));
1215 
1216 	/* Unicast and locally administered MAC */
1217 	dev->dev_addr[0] = phy_port << 4 | 0x02;
1218 	hash = jhash2((u32 *)xd->local_uuid, 4, 0);
1219 	memcpy(dev->dev_addr + 1, &hash, sizeof(hash));
1220 	hash = jhash2((u32 *)xd->local_uuid, 4, hash);
1221 	dev->dev_addr[5] = hash & 0xff;
1222 }
1223 
tbnet_probe(struct tb_service * svc,const struct tb_service_id * id)1224 static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
1225 {
1226 	struct tb_xdomain *xd = tb_service_parent(svc);
1227 	struct net_device *dev;
1228 	struct tbnet *net;
1229 	int ret;
1230 
1231 	dev = alloc_etherdev(sizeof(*net));
1232 	if (!dev)
1233 		return -ENOMEM;
1234 
1235 	SET_NETDEV_DEV(dev, &svc->dev);
1236 
1237 	net = netdev_priv(dev);
1238 	INIT_DELAYED_WORK(&net->login_work, tbnet_login_work);
1239 	INIT_WORK(&net->connected_work, tbnet_connected_work);
1240 	INIT_WORK(&net->disconnect_work, tbnet_disconnect_work);
1241 	mutex_init(&net->connection_lock);
1242 	atomic_set(&net->command_id, 0);
1243 	atomic_set(&net->frame_id, 0);
1244 	net->svc = svc;
1245 	net->dev = dev;
1246 	net->xd = xd;
1247 
1248 	tbnet_generate_mac(dev);
1249 
1250 	strcpy(dev->name, "thunderbolt%d");
1251 	dev->netdev_ops = &tbnet_netdev_ops;
1252 
1253 	/* ThunderboltIP takes advantage of TSO packets but instead of
1254 	 * segmenting them we just split the packet into Thunderbolt
1255 	 * frames (maximum payload size of each frame is 4084 bytes) and
1256 	 * calculate checksum over the whole packet here.
1257 	 *
1258 	 * The receiving side does the opposite if the host OS supports
1259 	 * LRO, otherwise it needs to split the large packet into MTU
1260 	 * sized smaller packets.
1261 	 *
1262 	 * In order to receive large packets from the networking stack,
1263 	 * we need to announce support for most of the offloading
1264 	 * features here.
1265 	 */
1266 	dev->hw_features = NETIF_F_SG | NETIF_F_ALL_TSO | NETIF_F_GRO |
1267 			   NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
1268 	dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1269 	dev->hard_header_len += sizeof(struct thunderbolt_ip_frame_header);
1270 
1271 	netif_napi_add(dev, &net->napi, tbnet_poll, NAPI_POLL_WEIGHT);
1272 
1273 	/* MTU range: 68 - 65522 */
1274 	dev->min_mtu = ETH_MIN_MTU;
1275 	dev->max_mtu = TBNET_MAX_MTU - ETH_HLEN;
1276 
1277 	net->handler.uuid = &tbnet_svc_uuid;
1278 	net->handler.callback = tbnet_handle_packet;
1279 	net->handler.data = net;
1280 	tb_register_protocol_handler(&net->handler);
1281 
1282 	tb_service_set_drvdata(svc, net);
1283 
1284 	ret = register_netdev(dev);
1285 	if (ret) {
1286 		tb_unregister_protocol_handler(&net->handler);
1287 		free_netdev(dev);
1288 		return ret;
1289 	}
1290 
1291 	return 0;
1292 }
1293 
tbnet_remove(struct tb_service * svc)1294 static void tbnet_remove(struct tb_service *svc)
1295 {
1296 	struct tbnet *net = tb_service_get_drvdata(svc);
1297 
1298 	unregister_netdev(net->dev);
1299 	tb_unregister_protocol_handler(&net->handler);
1300 	free_netdev(net->dev);
1301 }
1302 
tbnet_shutdown(struct tb_service * svc)1303 static void tbnet_shutdown(struct tb_service *svc)
1304 {
1305 	tbnet_tear_down(tb_service_get_drvdata(svc), true);
1306 }
1307 
tbnet_suspend(struct device * dev)1308 static int __maybe_unused tbnet_suspend(struct device *dev)
1309 {
1310 	struct tb_service *svc = tb_to_service(dev);
1311 	struct tbnet *net = tb_service_get_drvdata(svc);
1312 
1313 	stop_login(net);
1314 	if (netif_running(net->dev)) {
1315 		netif_device_detach(net->dev);
1316 		tbnet_tear_down(net, true);
1317 	}
1318 
1319 	tb_unregister_protocol_handler(&net->handler);
1320 	return 0;
1321 }
1322 
tbnet_resume(struct device * dev)1323 static int __maybe_unused tbnet_resume(struct device *dev)
1324 {
1325 	struct tb_service *svc = tb_to_service(dev);
1326 	struct tbnet *net = tb_service_get_drvdata(svc);
1327 
1328 	tb_register_protocol_handler(&net->handler);
1329 
1330 	netif_carrier_off(net->dev);
1331 	if (netif_running(net->dev)) {
1332 		netif_device_attach(net->dev);
1333 		start_login(net);
1334 	}
1335 
1336 	return 0;
1337 }
1338 
1339 static const struct dev_pm_ops tbnet_pm_ops = {
1340 	SET_SYSTEM_SLEEP_PM_OPS(tbnet_suspend, tbnet_resume)
1341 };
1342 
1343 static const struct tb_service_id tbnet_ids[] = {
1344 	{ TB_SERVICE("network", 1) },
1345 	{ },
1346 };
1347 MODULE_DEVICE_TABLE(tbsvc, tbnet_ids);
1348 
1349 static struct tb_service_driver tbnet_driver = {
1350 	.driver = {
1351 		.owner = THIS_MODULE,
1352 		.name = "thunderbolt-net",
1353 		.pm = &tbnet_pm_ops,
1354 	},
1355 	.probe = tbnet_probe,
1356 	.remove = tbnet_remove,
1357 	.shutdown = tbnet_shutdown,
1358 	.id_table = tbnet_ids,
1359 };
1360 
tbnet_init(void)1361 static int __init tbnet_init(void)
1362 {
1363 	int ret;
1364 
1365 	tbnet_dir = tb_property_create_dir(&tbnet_dir_uuid);
1366 	if (!tbnet_dir)
1367 		return -ENOMEM;
1368 
1369 	tb_property_add_immediate(tbnet_dir, "prtcid", 1);
1370 	tb_property_add_immediate(tbnet_dir, "prtcvers", 1);
1371 	tb_property_add_immediate(tbnet_dir, "prtcrevs", 1);
1372 	/* Currently only announce support for match frags ID (bit 1). Bit 0
1373 	 * is reserved for full E2E flow control which we do not support at
1374 	 * the moment.
1375 	 */
1376 	tb_property_add_immediate(tbnet_dir, "prtcstns",
1377 				  TBNET_MATCH_FRAGS_ID | TBNET_64K_FRAMES);
1378 
1379 	ret = tb_register_property_dir("network", tbnet_dir);
1380 	if (ret)
1381 		goto err_free_dir;
1382 
1383 	ret = tb_register_service_driver(&tbnet_driver);
1384 	if (ret)
1385 		goto err_unregister;
1386 
1387 	return 0;
1388 
1389 err_unregister:
1390 	tb_unregister_property_dir("network", tbnet_dir);
1391 err_free_dir:
1392 	tb_property_free_dir(tbnet_dir);
1393 
1394 	return ret;
1395 }
1396 module_init(tbnet_init);
1397 
tbnet_exit(void)1398 static void __exit tbnet_exit(void)
1399 {
1400 	tb_unregister_service_driver(&tbnet_driver);
1401 	tb_unregister_property_dir("network", tbnet_dir);
1402 	tb_property_free_dir(tbnet_dir);
1403 }
1404 module_exit(tbnet_exit);
1405 
1406 MODULE_AUTHOR("Amir Levy <amir.jer.levy@intel.com>");
1407 MODULE_AUTHOR("Michael Jamet <michael.jamet@intel.com>");
1408 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
1409 MODULE_DESCRIPTION("Thunderbolt network driver");
1410 MODULE_LICENSE("GPL v2");
1411