1	// SPDX-License-Identifier: GPL-2.0
2	/*
3	* Networking over Thunderbolt/USB4 cables using USB4NET protocol
4	* (formerly Apple ThunderboltIP).
5	*
6	* Copyright (C) 2017, Intel Corporation
7	* Authors: Amir Levy <amir.jer.levy@intel.com>
8	* Michael Jamet <michael.jamet@intel.com>
9	* Mika Westerberg <mika.westerberg@linux.intel.com>
10	*/
11
12	#include <linux/atomic.h>
13	#include <linux/highmem.h>
14	#include <linux/if_vlan.h>
15	#include <linux/jhash.h>
16	#include <linux/module.h>
17	#include <linux/etherdevice.h>
18	#include <linux/rtnetlink.h>
19	#include <linux/sizes.h>
20	#include <linux/thunderbolt.h>
21	#include <linux/uuid.h>
22	#include <linux/workqueue.h>
23
24	#include <net/ip6_checksum.h>
25
26	#include "trace.h"
27
28	/* Protocol timeouts in ms */
29	#define TBNET_LOGIN_DELAY 4500
30	#define TBNET_LOGIN_TIMEOUT 500
31	#define TBNET_LOGOUT_TIMEOUT 1000
32
33	#define TBNET_RING_SIZE 256
34	#define TBNET_LOGIN_RETRIES 60
35	#define TBNET_LOGOUT_RETRIES 10
36	#define TBNET_E2E BIT(0)
37	#define TBNET_MATCH_FRAGS_ID BIT(1)
38	#define TBNET_64K_FRAMES BIT(2)
39	#define TBNET_MAX_MTU SZ_64K
40	#define TBNET_FRAME_SIZE SZ_4K
41	#define TBNET_MAX_PAYLOAD_SIZE \
42	(TBNET_FRAME_SIZE - sizeof(struct thunderbolt_ip_frame_header))
43	/* Rx packets need to hold space for skb_shared_info */
44	#define TBNET_RX_MAX_SIZE \
45	(TBNET_FRAME_SIZE + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
46	#define TBNET_RX_PAGE_ORDER get_order(TBNET_RX_MAX_SIZE)
47	#define TBNET_RX_PAGE_SIZE (PAGE_SIZE << TBNET_RX_PAGE_ORDER)
48
49	#define TBNET_L0_PORT_NUM(route) ((route) & GENMASK(5, 0))
50
51	/**
52	* struct thunderbolt_ip_frame_header - Header for each Thunderbolt frame
53	* @frame_size: size of the data with the frame
54	* @frame_index: running index on the frames
55	* @frame_id: ID of the frame to match frames to specific packet
56	* @frame_count: how many frames assembles a full packet
57	*
58	* Each data frame passed to the high-speed DMA ring has this header. If
59	* the XDomain network directory announces that %TBNET_MATCH_FRAGS_ID is
60	* supported then @frame_id is filled, otherwise it stays %0.
61	*/
62	struct thunderbolt_ip_frame_header {
63	__le32 frame_size;
64	__le16 frame_index;
65	__le16 frame_id;
66	__le32 frame_count;
67	};
68
69	enum thunderbolt_ip_frame_pdf {
70	TBIP_PDF_FRAME_START = 1,
71	TBIP_PDF_FRAME_END,
72	};
73
74	enum thunderbolt_ip_type {
75	TBIP_LOGIN,
76	TBIP_LOGIN_RESPONSE,
77	TBIP_LOGOUT,
78	TBIP_STATUS,
79	};
80
81	struct thunderbolt_ip_header {
82	u32 route_hi;
83	u32 route_lo;
84	u32 length_sn;
85	uuid_t uuid;
86	uuid_t initiator_uuid;
87	uuid_t target_uuid;
88	u32 type;
89	u32 command_id;
90	};
91
92	#define TBIP_HDR_LENGTH_MASK GENMASK(5, 0)
93	#define TBIP_HDR_SN_MASK GENMASK(28, 27)
94	#define TBIP_HDR_SN_SHIFT 27
95
96	struct thunderbolt_ip_login {
97	struct thunderbolt_ip_header hdr;
98	u32 proto_version;
99	u32 transmit_path;
100	u32 reserved[4];
101	};
102
103	#define TBIP_LOGIN_PROTO_VERSION 1
104
105	struct thunderbolt_ip_login_response {
106	struct thunderbolt_ip_header hdr;
107	u32 status;
108	u32 receiver_mac[2];
109	u32 receiver_mac_len;
110	u32 reserved[4];
111	};
112
113	struct thunderbolt_ip_logout {
114	struct thunderbolt_ip_header hdr;
115	};
116
117	struct thunderbolt_ip_status {
118	struct thunderbolt_ip_header hdr;
119	u32 status;
120	};
121
122	struct tbnet_stats {
123	u64 tx_packets;
124	u64 rx_packets;
125	u64 tx_bytes;
126	u64 rx_bytes;
127	u64 rx_errors;
128	u64 tx_errors;
129	u64 rx_length_errors;
130	u64 rx_over_errors;
131	u64 rx_crc_errors;
132	u64 rx_missed_errors;
133	};
134
135	struct tbnet_frame {
136	struct net_device *dev;
137	struct page *page;
138	struct ring_frame frame;
139	};
140
141	struct tbnet_ring {
142	struct tbnet_frame frames[TBNET_RING_SIZE];
143	unsigned int cons;
144	unsigned int prod;
145	struct tb_ring *ring;
146	};
147
148	/**
149	* struct tbnet - ThunderboltIP network driver private data
150	* @svc: XDomain service the driver is bound to
151	* @xd: XDomain the service belongs to
152	* @handler: ThunderboltIP configuration protocol handler
153	* @dev: Networking device
154	* @napi: NAPI structure for Rx polling
155	* @stats: Network statistics
156	* @skb: Network packet that is currently processed on Rx path
157	* @command_id: ID used for next configuration protocol packet
158	* @login_sent: ThunderboltIP login message successfully sent
159	* @login_received: ThunderboltIP login message received from the remote
160	* host
161	* @local_transmit_path: HopID we are using to send out packets
162	* @remote_transmit_path: HopID the other end is using to send packets to us
163	* @connection_lock: Lock serializing access to @login_sent,
164	* @login_received and @transmit_path.
165	* @login_retries: Number of login retries currently done
166	* @login_work: Worker to send ThunderboltIP login packets
167	* @connected_work: Worker that finalizes the ThunderboltIP connection
168	* setup and enables DMA paths for high speed data
169	* transfers
170	* @disconnect_work: Worker that handles tearing down the ThunderboltIP
171	* connection
172	* @rx_hdr: Copy of the currently processed Rx frame. Used when a
173	* network packet consists of multiple Thunderbolt frames.
174	* In host byte order.
175	* @rx_ring: Software ring holding Rx frames
176	* @frame_id: Frame ID use for next Tx packet
177	* (if %TBNET_MATCH_FRAGS_ID is supported in both ends)
178	* @tx_ring: Software ring holding Tx frames
179	*/
180	struct tbnet {
181	const struct tb_service *svc;
182	struct tb_xdomain *xd;
183	struct tb_protocol_handler handler;
184	struct net_device *dev;
185	struct napi_struct napi;
186	struct tbnet_stats stats;
187	struct sk_buff *skb;
188	atomic_t command_id;
189	bool login_sent;
190	bool login_received;
191	int local_transmit_path;
192	int remote_transmit_path;
193	struct mutex connection_lock;
194	int login_retries;
195	struct delayed_work login_work;
196	struct work_struct connected_work;
197	struct work_struct disconnect_work;
198	struct thunderbolt_ip_frame_header rx_hdr;
199	struct tbnet_ring rx_ring;
200	atomic_t frame_id;
201	struct tbnet_ring tx_ring;
202	};
203
204	/* Network property directory UUID: c66189ca-1cce-4195-bdb8-49592e5f5a4f */
205	static const uuid_t tbnet_dir_uuid =
206	UUID_INIT(0xc66189ca, 0x1cce, 0x4195,
207	0xbd, 0xb8, 0x49, 0x59, 0x2e, 0x5f, 0x5a, 0x4f);
208
209	/* ThunderboltIP protocol UUID: 798f589e-3616-8a47-97c6-5664a920c8dd */
210	static const uuid_t tbnet_svc_uuid =
211	UUID_INIT(0x798f589e, 0x3616, 0x8a47,
212	0x97, 0xc6, 0x56, 0x64, 0xa9, 0x20, 0xc8, 0xdd);
213
214	static struct tb_property_dir *tbnet_dir;
215
216	static bool tbnet_e2e = true;
217	module_param_named(e2e, tbnet_e2e, bool, 0444);
218	MODULE_PARM_DESC(e2e, "USB4NET full end-to-end flow control (default: true)");
219
220	static void tbnet_fill_header(struct thunderbolt_ip_header *hdr, u64 route,
221	u8 sequence, const uuid_t *initiator_uuid, const uuid_t *target_uuid,
222	enum thunderbolt_ip_type type, size_t size, u32 command_id)
223	{
224	u32 length_sn;
225
226	/* Length does not include route_hi/lo and length_sn fields */
227	length_sn = (size - 3 * 4) / 4;
228	length_sn |= (sequence << TBIP_HDR_SN_SHIFT) & TBIP_HDR_SN_MASK;
229
230	hdr->route_hi = upper_32_bits(route);
231	hdr->route_lo = lower_32_bits(route);
232	hdr->length_sn = length_sn;
233	uuid_copy(dst: &hdr->uuid, src: &tbnet_svc_uuid);
234	uuid_copy(dst: &hdr->initiator_uuid, src: initiator_uuid);
235	uuid_copy(dst: &hdr->target_uuid, src: target_uuid);
236	hdr->type = type;
237	hdr->command_id = command_id;
238	}
239
240	static int tbnet_login_response(struct tbnet *net, u64 route, u8 sequence,
241	u32 command_id)
242	{
243	struct thunderbolt_ip_login_response reply;
244	struct tb_xdomain *xd = net->xd;
245
246	memset(&reply, 0, sizeof(reply));
247	tbnet_fill_header(hdr: &reply.hdr, route, sequence, initiator_uuid: xd->local_uuid,
248	target_uuid: xd->remote_uuid, type: TBIP_LOGIN_RESPONSE, size: sizeof(reply),
249	command_id);
250	memcpy(reply.receiver_mac, net->dev->dev_addr, ETH_ALEN);
251	reply.receiver_mac_len = ETH_ALEN;
252
253	return tb_xdomain_response(xd, response: &reply, size: sizeof(reply),
254	type: TB_CFG_PKG_XDOMAIN_RESP);
255	}
256
257	static int tbnet_login_request(struct tbnet *net, u8 sequence)
258	{
259	struct thunderbolt_ip_login_response reply;
260	struct thunderbolt_ip_login request;
261	struct tb_xdomain *xd = net->xd;
262
263	memset(&request, 0, sizeof(request));
264	tbnet_fill_header(hdr: &request.hdr, route: xd->route, sequence, initiator_uuid: xd->local_uuid,
265	target_uuid: xd->remote_uuid, type: TBIP_LOGIN, size: sizeof(request),
266	command_id: atomic_inc_return(v: &net->command_id));
267
268	request.proto_version = TBIP_LOGIN_PROTO_VERSION;
269	request.transmit_path = net->local_transmit_path;
270
271	return tb_xdomain_request(xd, request: &request, request_size: sizeof(request),
272	request_type: TB_CFG_PKG_XDOMAIN_RESP, response: &reply,
273	response_size: sizeof(reply), response_type: TB_CFG_PKG_XDOMAIN_RESP,
274	TBNET_LOGIN_TIMEOUT);
275	}
276
277	static int tbnet_logout_response(struct tbnet *net, u64 route, u8 sequence,
278	u32 command_id)
279	{
280	struct thunderbolt_ip_status reply;
281	struct tb_xdomain *xd = net->xd;
282
283	memset(&reply, 0, sizeof(reply));
284	tbnet_fill_header(hdr: &reply.hdr, route, sequence, initiator_uuid: xd->local_uuid,
285	target_uuid: xd->remote_uuid, type: TBIP_STATUS, size: sizeof(reply),
286	command_id: atomic_inc_return(v: &net->command_id));
287	return tb_xdomain_response(xd, response: &reply, size: sizeof(reply),
288	type: TB_CFG_PKG_XDOMAIN_RESP);
289	}
290
291	static int tbnet_logout_request(struct tbnet *net)
292	{
293	struct thunderbolt_ip_logout request;
294	struct thunderbolt_ip_status reply;
295	struct tb_xdomain *xd = net->xd;
296
297	memset(&request, 0, sizeof(request));
298	tbnet_fill_header(hdr: &request.hdr, route: xd->route, sequence: 0, initiator_uuid: xd->local_uuid,
299	target_uuid: xd->remote_uuid, type: TBIP_LOGOUT, size: sizeof(request),
300	command_id: atomic_inc_return(v: &net->command_id));
301
302	return tb_xdomain_request(xd, request: &request, request_size: sizeof(request),
303	request_type: TB_CFG_PKG_XDOMAIN_RESP, response: &reply,
304	response_size: sizeof(reply), response_type: TB_CFG_PKG_XDOMAIN_RESP,
305	TBNET_LOGOUT_TIMEOUT);
306	}
307
308	static void start_login(struct tbnet *net)
309	{
310	netdev_dbg(net->dev, "login started\n");
311
312	mutex_lock(&net->connection_lock);
313	net->login_sent = false;
314	net->login_received = false;
315	mutex_unlock(lock: &net->connection_lock);
316
317	queue_delayed_work(wq: system_long_wq, dwork: &net->login_work,
318	delay: msecs_to_jiffies(m: 1000));
319	}
320
321	static void stop_login(struct tbnet *net)
322	{
323	cancel_delayed_work_sync(dwork: &net->login_work);
324	cancel_work_sync(work: &net->connected_work);
325
326	netdev_dbg(net->dev, "login stopped\n");
327	}
328
329	static inline unsigned int tbnet_frame_size(const struct tbnet_frame *tf)
330	{
331	return tf->frame.size ? : TBNET_FRAME_SIZE;
332	}
333
334	static void tbnet_free_buffers(struct tbnet_ring *ring)
335	{
336	unsigned int i;
337
338	for (i = 0; i < TBNET_RING_SIZE; i++) {
339	struct device *dma_dev = tb_ring_dma_device(ring: ring->ring);
340	struct tbnet_frame *tf = &ring->frames[i];
341	enum dma_data_direction dir;
342	unsigned int order;
343	size_t size;
344
345	if (!tf->page)
346	continue;
347
348	if (ring->ring->is_tx) {
349	dir = DMA_TO_DEVICE;
350	order = 0;
351	size = TBNET_FRAME_SIZE;
352	} else {
353	dir = DMA_FROM_DEVICE;
354	order = TBNET_RX_PAGE_ORDER;
355	size = TBNET_RX_PAGE_SIZE;
356	}
357
358	trace_tbnet_free_frame(index: i, page: tf->page, phys: tf->frame.buffer_phy, dir);
359
360	if (tf->frame.buffer_phy)
361	dma_unmap_page(dma_dev, tf->frame.buffer_phy, size,
362	dir);
363
364	__free_pages(page: tf->page, order);
365	tf->page = NULL;
366	}
367
368	ring->cons = 0;
369	ring->prod = 0;
370	}
371
372	static void tbnet_tear_down(struct tbnet *net, bool send_logout)
373	{
374	netif_carrier_off(dev: net->dev);
375	netif_stop_queue(dev: net->dev);
376
377	stop_login(net);
378
379	mutex_lock(&net->connection_lock);
380
381	if (net->login_sent && net->login_received) {
382	int ret, retries = TBNET_LOGOUT_RETRIES;
383
384	while (send_logout && retries-- > 0) {
385	netdev_dbg(net->dev, "sending logout request %u\n",
386	retries);
387	ret = tbnet_logout_request(net);
388	if (ret != -ETIMEDOUT)
389	break;
390	}
391
392	tb_ring_stop(ring: net->rx_ring.ring);
393	tb_ring_stop(ring: net->tx_ring.ring);
394	tbnet_free_buffers(ring: &net->rx_ring);
395	tbnet_free_buffers(ring: &net->tx_ring);
396
397	ret = tb_xdomain_disable_paths(xd: net->xd,
398	transmit_path: net->local_transmit_path,
399	transmit_ring: net->rx_ring.ring->hop,
400	receive_path: net->remote_transmit_path,
401	receive_ring: net->tx_ring.ring->hop);
402	if (ret)
403	netdev_warn(dev: net->dev, format: "failed to disable DMA paths\n");
404
405	tb_xdomain_release_in_hopid(xd: net->xd, hopid: net->remote_transmit_path);
406	net->remote_transmit_path = 0;
407	}
408
409	net->login_retries = 0;
410	net->login_sent = false;
411	net->login_received = false;
412
413	netdev_dbg(net->dev, "network traffic stopped\n");
414
415	mutex_unlock(lock: &net->connection_lock);
416	}
417
418	static int tbnet_handle_packet(const void *buf, size_t size, void *data)
419	{
420	const struct thunderbolt_ip_login *pkg = buf;
421	struct tbnet *net = data;
422	u32 command_id;
423	int ret = 0;
424	u32 sequence;
425	u64 route;
426
427	/* Make sure the packet is for us */
428	if (size < sizeof(struct thunderbolt_ip_header))
429	return 0;
430	if (!uuid_equal(u1: &pkg->hdr.initiator_uuid, u2: net->xd->remote_uuid))
431	return 0;
432	if (!uuid_equal(u1: &pkg->hdr.target_uuid, u2: net->xd->local_uuid))
433	return 0;
434
435	route = ((u64)pkg->hdr.route_hi << 32) | pkg->hdr.route_lo;
436	route &= ~BIT_ULL(63);
437	if (route != net->xd->route)
438	return 0;
439
440	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
441	sequence >>= TBIP_HDR_SN_SHIFT;
442	command_id = pkg->hdr.command_id;
443
444	switch (pkg->hdr.type) {
445	case TBIP_LOGIN:
446	netdev_dbg(net->dev, "remote login request received\n");
447	if (!netif_running(dev: net->dev))
448	break;
449
450	ret = tbnet_login_response(net, route, sequence,
451	command_id: pkg->hdr.command_id);
452	if (!ret) {
453	netdev_dbg(net->dev, "remote login response sent\n");
454
455	mutex_lock(&net->connection_lock);
456	net->login_received = true;
457	net->remote_transmit_path = pkg->transmit_path;
458
459	/* If we reached the number of max retries or
460	* previous logout, schedule another round of
461	* login retries
462	*/
463	if (net->login_retries >= TBNET_LOGIN_RETRIES ||
464	!net->login_sent) {
465	net->login_retries = 0;
466	queue_delayed_work(wq: system_long_wq,
467	dwork: &net->login_work, delay: 0);
468	}
469	mutex_unlock(lock: &net->connection_lock);
470
471	queue_work(wq: system_long_wq, work: &net->connected_work);
472	}
473	break;
474
475	case TBIP_LOGOUT:
476	netdev_dbg(net->dev, "remote logout request received\n");
477	ret = tbnet_logout_response(net, route, sequence, command_id);
478	if (!ret) {
479	netdev_dbg(net->dev, "remote logout response sent\n");
480	queue_work(wq: system_long_wq, work: &net->disconnect_work);
481	}
482	break;
483
484	default:
485	return 0;
486	}
487
488	if (ret)
489	netdev_warn(dev: net->dev, format: "failed to send ThunderboltIP response\n");
490
491	return 1;
492	}
493
494	static unsigned int tbnet_available_buffers(const struct tbnet_ring *ring)
495	{
496	return ring->prod - ring->cons;
497	}
498
499	static int tbnet_alloc_rx_buffers(struct tbnet *net, unsigned int nbuffers)
500	{
501	struct tbnet_ring *ring = &net->rx_ring;
502	int ret;
503
504	while (nbuffers--) {
505	struct device *dma_dev = tb_ring_dma_device(ring: ring->ring);
506	unsigned int index = ring->prod & (TBNET_RING_SIZE - 1);
507	struct tbnet_frame *tf = &ring->frames[index];
508	dma_addr_t dma_addr;
509
510	if (tf->page)
511	break;
512
513	/* Allocate page (order > 0) so that it can hold maximum
514	* ThunderboltIP frame (4kB) and the additional room for
515	* SKB shared info required by build_skb().
516	*/
517	tf->page = dev_alloc_pages(TBNET_RX_PAGE_ORDER);
518	if (!tf->page) {
519	ret = -ENOMEM;
520	goto err_free;
521	}
522
523	dma_addr = dma_map_page(dma_dev, tf->page, 0,
524	TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
525	if (dma_mapping_error(dev: dma_dev, dma_addr)) {
526	ret = -ENOMEM;
527	goto err_free;
528	}
529
530	tf->frame.buffer_phy = dma_addr;
531	tf->dev = net->dev;
532
533	trace_tbnet_alloc_rx_frame(index, page: tf->page, phys: dma_addr,
534	dir: DMA_FROM_DEVICE);
535
536	tb_ring_rx(ring: ring->ring, frame: &tf->frame);
537
538	ring->prod++;
539	}
540
541	return 0;
542
543	err_free:
544	tbnet_free_buffers(ring);
545	return ret;
546	}
547
548	static struct tbnet_frame *tbnet_get_tx_buffer(struct tbnet *net)
549	{
550	struct tbnet_ring *ring = &net->tx_ring;
551	struct device *dma_dev = tb_ring_dma_device(ring: ring->ring);
552	struct tbnet_frame *tf;
553	unsigned int index;
554
555	if (!tbnet_available_buffers(ring))
556	return NULL;
557
558	index = ring->cons++ & (TBNET_RING_SIZE - 1);
559
560	tf = &ring->frames[index];
561	tf->frame.size = 0;
562
563	dma_sync_single_for_cpu(dev: dma_dev, addr: tf->frame.buffer_phy,
564	size: tbnet_frame_size(tf), dir: DMA_TO_DEVICE);
565
566	return tf;
567	}
568
569	static void tbnet_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
570	bool canceled)
571	{
572	struct tbnet_frame *tf = container_of(frame, typeof(*tf), frame);
573	struct tbnet *net = netdev_priv(dev: tf->dev);
574
575	/* Return buffer to the ring */
576	net->tx_ring.prod++;
577
578	if (tbnet_available_buffers(ring: &net->tx_ring) >= TBNET_RING_SIZE / 2)
579	netif_wake_queue(dev: net->dev);
580	}
581
582	static int tbnet_alloc_tx_buffers(struct tbnet *net)
583	{
584	struct tbnet_ring *ring = &net->tx_ring;
585	struct device *dma_dev = tb_ring_dma_device(ring: ring->ring);
586	unsigned int i;
587
588	for (i = 0; i < TBNET_RING_SIZE; i++) {
589	struct tbnet_frame *tf = &ring->frames[i];
590	dma_addr_t dma_addr;
591
592	tf->page = alloc_page(GFP_KERNEL);
593	if (!tf->page) {
594	tbnet_free_buffers(ring);
595	return -ENOMEM;
596	}
597
598	dma_addr = dma_map_page(dma_dev, tf->page, 0, TBNET_FRAME_SIZE,
599	DMA_TO_DEVICE);
600	if (dma_mapping_error(dev: dma_dev, dma_addr)) {
601	__free_page(tf->page);
602	tf->page = NULL;
603	tbnet_free_buffers(ring);
604	return -ENOMEM;
605	}
606
607	tf->dev = net->dev;
608	tf->frame.buffer_phy = dma_addr;
609	tf->frame.callback = tbnet_tx_callback;
610	tf->frame.sof = TBIP_PDF_FRAME_START;
611	tf->frame.eof = TBIP_PDF_FRAME_END;
612
613	trace_tbnet_alloc_tx_frame(index: i, page: tf->page, phys: dma_addr, dir: DMA_TO_DEVICE);
614	}
615
616	ring->cons = 0;
617	ring->prod = TBNET_RING_SIZE - 1;
618
619	return 0;
620	}
621
622	static void tbnet_connected_work(struct work_struct *work)
623	{
624	struct tbnet *net = container_of(work, typeof(*net), connected_work);
625	bool connected;
626	int ret;
627
628	if (netif_carrier_ok(dev: net->dev))
629	return;
630
631	mutex_lock(&net->connection_lock);
632	connected = net->login_sent && net->login_received;
633	mutex_unlock(lock: &net->connection_lock);
634
635	if (!connected)
636	return;
637
638	netdev_dbg(net->dev, "login successful, enabling paths\n");
639
640	ret = tb_xdomain_alloc_in_hopid(xd: net->xd, hopid: net->remote_transmit_path);
641	if (ret != net->remote_transmit_path) {
642	netdev_err(dev: net->dev, format: "failed to allocate Rx HopID\n");
643	return;
644	}
645
646	/* Both logins successful so enable the rings, high-speed DMA
647	* paths and start the network device queue.
648	*
649	* Note we enable the DMA paths last to make sure we have primed
650	* the Rx ring before any incoming packets are allowed to
651	* arrive.
652	*/
653	tb_ring_start(ring: net->tx_ring.ring);
654	tb_ring_start(ring: net->rx_ring.ring);
655
656	ret = tbnet_alloc_rx_buffers(net, TBNET_RING_SIZE);
657	if (ret)
658	goto err_stop_rings;
659
660	ret = tbnet_alloc_tx_buffers(net);
661	if (ret)
662	goto err_free_rx_buffers;
663
664	ret = tb_xdomain_enable_paths(xd: net->xd, transmit_path: net->local_transmit_path,
665	transmit_ring: net->rx_ring.ring->hop,
666	receive_path: net->remote_transmit_path,
667	receive_ring: net->tx_ring.ring->hop);
668	if (ret) {
669	netdev_err(dev: net->dev, format: "failed to enable DMA paths\n");
670	goto err_free_tx_buffers;
671	}
672
673	netif_carrier_on(dev: net->dev);
674	netif_start_queue(dev: net->dev);
675
676	netdev_dbg(net->dev, "network traffic started\n");
677	return;
678
679	err_free_tx_buffers:
680	tbnet_free_buffers(ring: &net->tx_ring);
681	err_free_rx_buffers:
682	tbnet_free_buffers(ring: &net->rx_ring);
683	err_stop_rings:
684	tb_ring_stop(ring: net->rx_ring.ring);
685	tb_ring_stop(ring: net->tx_ring.ring);
686	tb_xdomain_release_in_hopid(xd: net->xd, hopid: net->remote_transmit_path);
687	}
688
689	static void tbnet_login_work(struct work_struct *work)
690	{
691	struct tbnet *net = container_of(work, typeof(*net), login_work.work);
692	unsigned long delay = msecs_to_jiffies(TBNET_LOGIN_DELAY);
693	int ret;
694
695	if (netif_carrier_ok(dev: net->dev))
696	return;
697
698	netdev_dbg(net->dev, "sending login request, retries=%u\n",
699	net->login_retries);
700
701	ret = tbnet_login_request(net, sequence: net->login_retries % 4);
702	if (ret) {
703	netdev_dbg(net->dev, "sending login request failed, ret=%d\n",
704	ret);
705	if (net->login_retries++ < TBNET_LOGIN_RETRIES) {
706	queue_delayed_work(wq: system_long_wq, dwork: &net->login_work,
707	delay);
708	} else {
709	netdev_info(dev: net->dev, format: "ThunderboltIP login timed out\n");
710	}
711	} else {
712	netdev_dbg(net->dev, "received login reply\n");
713
714	net->login_retries = 0;
715
716	mutex_lock(&net->connection_lock);
717	net->login_sent = true;
718	mutex_unlock(lock: &net->connection_lock);
719
720	queue_work(wq: system_long_wq, work: &net->connected_work);
721	}
722	}
723
724	static void tbnet_disconnect_work(struct work_struct *work)
725	{
726	struct tbnet *net = container_of(work, typeof(*net), disconnect_work);
727
728	tbnet_tear_down(net, send_logout: false);
729	}
730
731	static bool tbnet_check_frame(struct tbnet *net, const struct tbnet_frame *tf,
732	const struct thunderbolt_ip_frame_header *hdr)
733	{
734	u32 frame_id, frame_count, frame_size, frame_index;
735	unsigned int size;
736
737	if (tf->frame.flags & RING_DESC_CRC_ERROR) {
738	net->stats.rx_crc_errors++;
739	return false;
740	} else if (tf->frame.flags & RING_DESC_BUFFER_OVERRUN) {
741	net->stats.rx_over_errors++;
742	return false;
743	}
744
745	/* Should be greater than just header i.e. contains data */
746	size = tbnet_frame_size(tf);
747	if (size <= sizeof(*hdr)) {
748	net->stats.rx_length_errors++;
749	return false;
750	}
751
752	frame_count = le32_to_cpu(hdr->frame_count);
753	frame_size = le32_to_cpu(hdr->frame_size);
754	frame_index = le16_to_cpu(hdr->frame_index);
755	frame_id = le16_to_cpu(hdr->frame_id);
756
757	if ((frame_size > size - sizeof(*hdr)) || !frame_size) {
758	net->stats.rx_length_errors++;
759	return false;
760	}
761
762	/* In case we're in the middle of packet, validate the frame
763	* header based on first fragment of the packet.
764	*/
765	if (net->skb && net->rx_hdr.frame_count) {
766	/* Check the frame count fits the count field */
767	if (frame_count != le32_to_cpu(net->rx_hdr.frame_count)) {
768	net->stats.rx_length_errors++;
769	return false;
770	}
771
772	/* Check the frame identifiers are incremented correctly,
773	* and id is matching.
774	*/
775	if (frame_index != le16_to_cpu(net->rx_hdr.frame_index) + 1 ||
776	frame_id != le16_to_cpu(net->rx_hdr.frame_id)) {
777	net->stats.rx_missed_errors++;
778	return false;
779	}
780
781	if (net->skb->len + frame_size > TBNET_MAX_MTU) {
782	net->stats.rx_length_errors++;
783	return false;
784	}
785
786	return true;
787	}
788
789	/* Start of packet, validate the frame header */
790	if (frame_count == 0 || frame_count > TBNET_RING_SIZE / 4) {
791	net->stats.rx_length_errors++;
792	return false;
793	}
794	if (frame_index != 0) {
795	net->stats.rx_missed_errors++;
796	return false;
797	}
798
799	return true;
800	}
801
802	static int tbnet_poll(struct napi_struct *napi, int budget)
803	{
804	struct tbnet *net = container_of(napi, struct tbnet, napi);
805	unsigned int cleaned_count = tbnet_available_buffers(ring: &net->rx_ring);
806	struct device *dma_dev = tb_ring_dma_device(ring: net->rx_ring.ring);
807	unsigned int rx_packets = 0;
808
809	while (rx_packets < budget) {
810	const struct thunderbolt_ip_frame_header *hdr;
811	unsigned int hdr_size = sizeof(*hdr);
812	struct sk_buff *skb = NULL;
813	struct ring_frame *frame;
814	struct tbnet_frame *tf;
815	struct page *page;
816	bool last = true;
817	u32 frame_size;
818
819	/* Return some buffers to hardware, one at a time is too
820	* slow so allocate MAX_SKB_FRAGS buffers at the same
821	* time.
822	*/
823	if (cleaned_count >= MAX_SKB_FRAGS) {
824	tbnet_alloc_rx_buffers(net, nbuffers: cleaned_count);
825	cleaned_count = 0;
826	}
827
828	frame = tb_ring_poll(ring: net->rx_ring.ring);
829	if (!frame)
830	break;
831
832	dma_unmap_page(dma_dev, frame->buffer_phy,
833	TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
834
835	tf = container_of(frame, typeof(*tf), frame);
836
837	page = tf->page;
838	tf->page = NULL;
839	net->rx_ring.cons++;
840	cleaned_count++;
841
842	hdr = page_address(page);
843	if (!tbnet_check_frame(net, tf, hdr)) {
844	trace_tbnet_invalid_rx_ip_frame(size: hdr->frame_size,
845	id: hdr->frame_id, index: hdr->frame_index, count: hdr->frame_count);
846	__free_pages(page, TBNET_RX_PAGE_ORDER);
847	dev_kfree_skb_any(skb: net->skb);
848	net->skb = NULL;
849	continue;
850	}
851
852	trace_tbnet_rx_ip_frame(size: hdr->frame_size, id: hdr->frame_id,
853	index: hdr->frame_index, count: hdr->frame_count);
854	frame_size = le32_to_cpu(hdr->frame_size);
855
856	skb = net->skb;
857	if (!skb) {
858	skb = build_skb(page_address(page),
859	TBNET_RX_PAGE_SIZE);
860	if (!skb) {
861	__free_pages(page, TBNET_RX_PAGE_ORDER);
862	net->stats.rx_errors++;
863	break;
864	}
865
866	skb_reserve(skb, len: hdr_size);
867	skb_put(skb, len: frame_size);
868
869	net->skb = skb;
870	} else {
871	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
872	page, off: hdr_size, size: frame_size,
873	TBNET_RX_PAGE_SIZE - hdr_size);
874	}
875
876	net->rx_hdr.frame_size = hdr->frame_size;
877	net->rx_hdr.frame_count = hdr->frame_count;
878	net->rx_hdr.frame_index = hdr->frame_index;
879	net->rx_hdr.frame_id = hdr->frame_id;
880	last = le16_to_cpu(net->rx_hdr.frame_index) ==
881	le32_to_cpu(net->rx_hdr.frame_count) - 1;
882
883	rx_packets++;
884	net->stats.rx_bytes += frame_size;
885
886	if (last) {
887	skb->protocol = eth_type_trans(skb, dev: net->dev);
888	trace_tbnet_rx_skb(skb);
889	napi_gro_receive(napi: &net->napi, skb);
890	net->skb = NULL;
891	}
892	}
893
894	net->stats.rx_packets += rx_packets;
895
896	if (cleaned_count)
897	tbnet_alloc_rx_buffers(net, nbuffers: cleaned_count);
898
899	if (rx_packets >= budget)
900	return budget;
901
902	napi_complete_done(n: napi, work_done: rx_packets);
903	/* Re-enable the ring interrupt */
904	tb_ring_poll_complete(ring: net->rx_ring.ring);
905
906	return rx_packets;
907	}
908
909	static void tbnet_start_poll(void *data)
910	{
911	struct tbnet *net = data;
912
913	napi_schedule(n: &net->napi);
914	}
915
916	static int tbnet_open(struct net_device *dev)
917	{
918	struct tbnet *net = netdev_priv(dev);
919	struct tb_xdomain *xd = net->xd;
920	u16 sof_mask, eof_mask;
921	struct tb_ring *ring;
922	unsigned int flags;
923	int hopid;
924
925	netif_carrier_off(dev);
926
927	ring = tb_ring_alloc_tx(nhi: xd->tb->nhi, hop: -1, TBNET_RING_SIZE,
928	RING_FLAG_FRAME);
929	if (!ring) {
930	netdev_err(dev, format: "failed to allocate Tx ring\n");
931	return -ENOMEM;
932	}
933	net->tx_ring.ring = ring;
934
935	hopid = tb_xdomain_alloc_out_hopid(xd, hopid: -1);
936	if (hopid < 0) {
937	netdev_err(dev, format: "failed to allocate Tx HopID\n");
938	tb_ring_free(ring: net->tx_ring.ring);
939	net->tx_ring.ring = NULL;
940	return hopid;
941	}
942	net->local_transmit_path = hopid;
943
944	sof_mask = BIT(TBIP_PDF_FRAME_START);
945	eof_mask = BIT(TBIP_PDF_FRAME_END);
946
947	flags = RING_FLAG_FRAME;
948	/* Only enable full E2E if the other end supports it too */
949	if (tbnet_e2e && net->svc->prtcstns & TBNET_E2E)
950	flags |= RING_FLAG_E2E;
951
952	ring = tb_ring_alloc_rx(nhi: xd->tb->nhi, hop: -1, TBNET_RING_SIZE, flags,
953	e2e_tx_hop: net->tx_ring.ring->hop, sof_mask,
954	eof_mask, start_poll: tbnet_start_poll, poll_data: net);
955	if (!ring) {
956	netdev_err(dev, format: "failed to allocate Rx ring\n");
957	tb_xdomain_release_out_hopid(xd, hopid);
958	tb_ring_free(ring: net->tx_ring.ring);
959	net->tx_ring.ring = NULL;
960	return -ENOMEM;
961	}
962	net->rx_ring.ring = ring;
963
964	napi_enable(n: &net->napi);
965	start_login(net);
966
967	return 0;
968	}
969
970	static int tbnet_stop(struct net_device *dev)
971	{
972	struct tbnet *net = netdev_priv(dev);
973
974	napi_disable(n: &net->napi);
975
976	cancel_work_sync(work: &net->disconnect_work);
977	tbnet_tear_down(net, send_logout: true);
978
979	tb_ring_free(ring: net->rx_ring.ring);
980	net->rx_ring.ring = NULL;
981
982	tb_xdomain_release_out_hopid(xd: net->xd, hopid: net->local_transmit_path);
983	tb_ring_free(ring: net->tx_ring.ring);
984	net->tx_ring.ring = NULL;
985
986	return 0;
987	}
988
989	static bool tbnet_xmit_csum_and_map(struct tbnet *net, struct sk_buff *skb,
990	struct tbnet_frame **frames, u32 frame_count)
991	{
992	struct thunderbolt_ip_frame_header *hdr = page_address(frames[0]->page);
993	struct device *dma_dev = tb_ring_dma_device(ring: net->tx_ring.ring);
994	unsigned int i, len, offset = skb_transport_offset(skb);
995	/* Remove payload length from checksum */
996	u32 paylen = skb->len - skb_transport_offset(skb);
997	__wsum wsum = (__force __wsum)htonl(paylen);
998	__be16 protocol = skb->protocol;
999	void *data = skb->data;
1000	void *dest = hdr + 1;
1001	__sum16 *tucso;
1002
1003	if (skb->ip_summed != CHECKSUM_PARTIAL) {
1004	/* No need to calculate checksum so we just update the
1005	* total frame count and sync the frames for DMA.
1006	*/
1007	for (i = 0; i < frame_count; i++) {
1008	hdr = page_address(frames[i]->page);
1009	hdr->frame_count = cpu_to_le32(frame_count);
1010	trace_tbnet_tx_ip_frame(size: hdr->frame_size, id: hdr->frame_id,
1011	index: hdr->frame_index, count: hdr->frame_count);
1012	dma_sync_single_for_device(dev: dma_dev,
1013	addr: frames[i]->frame.buffer_phy,
1014	size: tbnet_frame_size(tf: frames[i]), dir: DMA_TO_DEVICE);
1015	}
1016
1017	return true;
1018	}
1019
1020	if (protocol == htons(ETH_P_8021Q)) {
1021	struct vlan_hdr *vhdr, vh;
1022
1023	vhdr = skb_header_pointer(skb, ETH_HLEN, len: sizeof(vh), buffer: &vh);
1024	if (!vhdr)
1025	return false;
1026
1027	protocol = vhdr->h_vlan_encapsulated_proto;
1028	}
1029
1030	/* Data points on the beginning of packet.
1031	* Check is the checksum absolute place in the packet.
1032	* ipcso will update IP checksum.
1033	* tucso will update TCP/UDP checksum.
1034	*/
1035	if (protocol == htons(ETH_P_IP)) {
1036	__sum16 *ipcso = dest + ((void *)&(ip_hdr(skb)->check) - data);
1037
1038	*ipcso = 0;
1039	*ipcso = ip_fast_csum(iph: dest + skb_network_offset(skb),
1040	ihl: ip_hdr(skb)->ihl);
1041
1042	if (ip_hdr(skb)->protocol == IPPROTO_TCP)
1043	tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
1044	else if (ip_hdr(skb)->protocol == IPPROTO_UDP)
1045	tucso = dest + ((void *)&(udp_hdr(skb)->check) - data);
1046	else
1047	return false;
1048
1049	*tucso = ~csum_tcpudp_magic(saddr: ip_hdr(skb)->saddr,
1050	daddr: ip_hdr(skb)->daddr, len: 0,
1051	proto: ip_hdr(skb)->protocol, sum: 0);
1052	} else if (skb_is_gso(skb) && skb_is_gso_v6(skb)) {
1053	tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
1054	*tucso = ~csum_ipv6_magic(saddr: &ipv6_hdr(skb)->saddr,
1055	daddr: &ipv6_hdr(skb)->daddr, len: 0,
1056	IPPROTO_TCP, sum: 0);
1057	} else if (protocol == htons(ETH_P_IPV6)) {
1058	tucso = dest + skb_checksum_start_offset(skb) + skb->csum_offset;
1059	*tucso = ~csum_ipv6_magic(saddr: &ipv6_hdr(skb)->saddr,
1060	daddr: &ipv6_hdr(skb)->daddr, len: 0,
1061	proto: ipv6_hdr(skb)->nexthdr, sum: 0);
1062	} else {
1063	return false;
1064	}
1065
1066	/* First frame was headers, rest of the frames contain data.
1067	* Calculate checksum over each frame.
1068	*/
1069	for (i = 0; i < frame_count; i++) {
1070	hdr = page_address(frames[i]->page);
1071	dest = (void *)(hdr + 1) + offset;
1072	len = le32_to_cpu(hdr->frame_size) - offset;
1073	wsum = csum_partial(buff: dest, len, sum: wsum);
1074	hdr->frame_count = cpu_to_le32(frame_count);
1075	trace_tbnet_tx_ip_frame(size: hdr->frame_size, id: hdr->frame_id,
1076	index: hdr->frame_index, count: hdr->frame_count);
1077
1078	offset = 0;
1079	}
1080
1081	*tucso = csum_fold(sum: wsum);
1082
1083	/* Checksum is finally calculated and we don't touch the memory
1084	* anymore, so DMA sync the frames now.
1085	*/
1086	for (i = 0; i < frame_count; i++) {
1087	dma_sync_single_for_device(dev: dma_dev, addr: frames[i]->frame.buffer_phy,
1088	size: tbnet_frame_size(tf: frames[i]), dir: DMA_TO_DEVICE);
1089	}
1090
1091	return true;
1092	}
1093
1094	static void *tbnet_kmap_frag(struct sk_buff *skb, unsigned int frag_num,
1095	unsigned int *len)
1096	{
1097	const skb_frag_t *frag = &skb_shinfo(skb)->frags[frag_num];
1098
1099	*len = skb_frag_size(frag);
1100	return kmap_local_page(page: skb_frag_page(frag)) + skb_frag_off(frag);
1101	}
1102
1103	static netdev_tx_t tbnet_start_xmit(struct sk_buff *skb,
1104	struct net_device *dev)
1105	{
1106	struct tbnet *net = netdev_priv(dev);
1107	struct tbnet_frame *frames[MAX_SKB_FRAGS];
1108	u16 frame_id = atomic_read(v: &net->frame_id);
1109	struct thunderbolt_ip_frame_header *hdr;
1110	unsigned int len = skb_headlen(skb);
1111	unsigned int data_len = skb->len;
1112	unsigned int nframes, i;
1113	unsigned int frag = 0;
1114	void *src = skb->data;
1115	u32 frame_index = 0;
1116	bool unmap = false;
1117	void *dest;
1118
1119	trace_tbnet_tx_skb(skb);
1120
1121	nframes = DIV_ROUND_UP(data_len, TBNET_MAX_PAYLOAD_SIZE);
1122	if (tbnet_available_buffers(ring: &net->tx_ring) < nframes) {
1123	netif_stop_queue(dev: net->dev);
1124	return NETDEV_TX_BUSY;
1125	}
1126
1127	frames[frame_index] = tbnet_get_tx_buffer(net);
1128	if (!frames[frame_index])
1129	goto err_drop;
1130
1131	hdr = page_address(frames[frame_index]->page);
1132	dest = hdr + 1;
1133
1134	/* If overall packet is bigger than the frame data size */
1135	while (data_len > TBNET_MAX_PAYLOAD_SIZE) {
1136	unsigned int size_left = TBNET_MAX_PAYLOAD_SIZE;
1137
1138	hdr->frame_size = cpu_to_le32(TBNET_MAX_PAYLOAD_SIZE);
1139	hdr->frame_index = cpu_to_le16(frame_index);
1140	hdr->frame_id = cpu_to_le16(frame_id);
1141
1142	do {
1143	if (len > size_left) {
1144	/* Copy data onto Tx buffer data with
1145	* full frame size then break and go to
1146	* next frame
1147	*/
1148	memcpy(dest, src, size_left);
1149	len -= size_left;
1150	dest += size_left;
1151	src += size_left;
1152	break;
1153	}
1154
1155	memcpy(dest, src, len);
1156	size_left -= len;
1157	dest += len;
1158
1159	if (unmap) {
1160	kunmap_local(src);
1161	unmap = false;
1162	}
1163
1164	/* Ensure all fragments have been processed */
1165	if (frag < skb_shinfo(skb)->nr_frags) {
1166	/* Map and then unmap quickly */
1167	src = tbnet_kmap_frag(skb, frag_num: frag++, len: &len);
1168	unmap = true;
1169	} else if (unlikely(size_left > 0)) {
1170	goto err_drop;
1171	}
1172	} while (size_left > 0);
1173
1174	data_len -= TBNET_MAX_PAYLOAD_SIZE;
1175	frame_index++;
1176
1177	frames[frame_index] = tbnet_get_tx_buffer(net);
1178	if (!frames[frame_index])
1179	goto err_drop;
1180
1181	hdr = page_address(frames[frame_index]->page);
1182	dest = hdr + 1;
1183	}
1184
1185	hdr->frame_size = cpu_to_le32(data_len);
1186	hdr->frame_index = cpu_to_le16(frame_index);
1187	hdr->frame_id = cpu_to_le16(frame_id);
1188
1189	frames[frame_index]->frame.size = data_len + sizeof(*hdr);
1190
1191	/* In case the remaining data_len is smaller than a frame */
1192	while (len < data_len) {
1193	memcpy(dest, src, len);
1194	data_len -= len;
1195	dest += len;
1196
1197	if (unmap) {
1198	kunmap_local(src);
1199	unmap = false;
1200	}
1201
1202	if (frag < skb_shinfo(skb)->nr_frags) {
1203	src = tbnet_kmap_frag(skb, frag_num: frag++, len: &len);
1204	unmap = true;
1205	} else if (unlikely(data_len > 0)) {
1206	goto err_drop;
1207	}
1208	}
1209
1210	memcpy(dest, src, data_len);
1211
1212	if (unmap)
1213	kunmap_local(src);
1214
1215	if (!tbnet_xmit_csum_and_map(net, skb, frames, frame_count: frame_index + 1))
1216	goto err_drop;
1217
1218	for (i = 0; i < frame_index + 1; i++)
1219	tb_ring_tx(ring: net->tx_ring.ring, frame: &frames[i]->frame);
1220
1221	if (net->svc->prtcstns & TBNET_MATCH_FRAGS_ID)
1222	atomic_inc(v: &net->frame_id);
1223
1224	net->stats.tx_packets++;
1225	net->stats.tx_bytes += skb->len;
1226
1227	trace_tbnet_consume_skb(skb);
1228	dev_consume_skb_any(skb);
1229
1230	return NETDEV_TX_OK;
1231
1232	err_drop:
1233	/* We can re-use the buffers */
1234	net->tx_ring.cons -= frame_index;
1235
1236	dev_kfree_skb_any(skb);
1237	net->stats.tx_errors++;
1238
1239	return NETDEV_TX_OK;
1240	}
1241
1242	static void tbnet_get_stats64(struct net_device *dev,
1243	struct rtnl_link_stats64 *stats)
1244	{
1245	struct tbnet *net = netdev_priv(dev);
1246
1247	stats->tx_packets = net->stats.tx_packets;
1248	stats->rx_packets = net->stats.rx_packets;
1249	stats->tx_bytes = net->stats.tx_bytes;
1250	stats->rx_bytes = net->stats.rx_bytes;
1251	stats->rx_errors = net->stats.rx_errors + net->stats.rx_length_errors +
1252	net->stats.rx_over_errors + net->stats.rx_crc_errors +
1253	net->stats.rx_missed_errors;
1254	stats->tx_errors = net->stats.tx_errors;
1255	stats->rx_length_errors = net->stats.rx_length_errors;
1256	stats->rx_over_errors = net->stats.rx_over_errors;
1257	stats->rx_crc_errors = net->stats.rx_crc_errors;
1258	stats->rx_missed_errors = net->stats.rx_missed_errors;
1259	}
1260
1261	static const struct net_device_ops tbnet_netdev_ops = {
1262	.ndo_open = tbnet_open,
1263	.ndo_stop = tbnet_stop,
1264	.ndo_start_xmit = tbnet_start_xmit,
1265	.ndo_get_stats64 = tbnet_get_stats64,
1266	};
1267
1268	static void tbnet_generate_mac(struct net_device *dev)
1269	{
1270	const struct tbnet *net = netdev_priv(dev);
1271	const struct tb_xdomain *xd = net->xd;
1272	u8 addr[ETH_ALEN];
1273	u8 phy_port;
1274	u32 hash;
1275
1276	phy_port = tb_phy_port_from_link(TBNET_L0_PORT_NUM(xd->route));
1277
1278	/* Unicast and locally administered MAC */
1279	addr[0] = phy_port << 4 | 0x02;
1280	hash = jhash2(k: (u32 *)xd->local_uuid, length: 4, initval: 0);
1281	memcpy(addr + 1, &hash, sizeof(hash));
1282	hash = jhash2(k: (u32 *)xd->local_uuid, length: 4, initval: hash);
1283	addr[5] = hash & 0xff;
1284	eth_hw_addr_set(dev, addr);
1285	}
1286
1287	static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
1288	{
1289	struct tb_xdomain *xd = tb_service_parent(svc);
1290	struct net_device *dev;
1291	struct tbnet *net;
1292	int ret;
1293
1294	dev = alloc_etherdev(sizeof(*net));
1295	if (!dev)
1296	return -ENOMEM;
1297
1298	SET_NETDEV_DEV(dev, &svc->dev);
1299
1300	net = netdev_priv(dev);
1301	INIT_DELAYED_WORK(&net->login_work, tbnet_login_work);
1302	INIT_WORK(&net->connected_work, tbnet_connected_work);
1303	INIT_WORK(&net->disconnect_work, tbnet_disconnect_work);
1304	mutex_init(&net->connection_lock);
1305	atomic_set(v: &net->command_id, i: 0);
1306	atomic_set(v: &net->frame_id, i: 0);
1307	net->svc = svc;
1308	net->dev = dev;
1309	net->xd = xd;
1310
1311	tbnet_generate_mac(dev);
1312
1313	strcpy(p: dev->name, q: "thunderbolt%d");
1314	dev->netdev_ops = &tbnet_netdev_ops;
1315
1316	/* ThunderboltIP takes advantage of TSO packets but instead of
1317	* segmenting them we just split the packet into Thunderbolt
1318	* frames (maximum payload size of each frame is 4084 bytes) and
1319	* calculate checksum over the whole packet here.
1320	*
1321	* The receiving side does the opposite if the host OS supports
1322	* LRO, otherwise it needs to split the large packet into MTU
1323	* sized smaller packets.
1324	*
1325	* In order to receive large packets from the networking stack,
1326	* we need to announce support for most of the offloading
1327	* features here.
1328	*/
1329	dev->hw_features = NETIF_F_SG | NETIF_F_ALL_TSO | NETIF_F_GRO |
1330	NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
1331	dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1332	dev->hard_header_len += sizeof(struct thunderbolt_ip_frame_header);
1333
1334	netif_napi_add(dev, napi: &net->napi, poll: tbnet_poll);
1335
1336	/* MTU range: 68 - 65522 */
1337	dev->min_mtu = ETH_MIN_MTU;
1338	dev->max_mtu = TBNET_MAX_MTU - ETH_HLEN;
1339
1340	net->handler.uuid = &tbnet_svc_uuid;
1341	net->handler.callback = tbnet_handle_packet;
1342	net->handler.data = net;
1343	tb_register_protocol_handler(handler: &net->handler);
1344
1345	tb_service_set_drvdata(svc, data: net);
1346
1347	ret = register_netdev(dev);
1348	if (ret) {
1349	tb_unregister_protocol_handler(handler: &net->handler);
1350	free_netdev(dev);
1351	return ret;
1352	}
1353
1354	return 0;
1355	}
1356
1357	static void tbnet_remove(struct tb_service *svc)
1358	{
1359	struct tbnet *net = tb_service_get_drvdata(svc);
1360
1361	unregister_netdev(dev: net->dev);
1362	tb_unregister_protocol_handler(handler: &net->handler);
1363	free_netdev(dev: net->dev);
1364	}
1365
1366	static void tbnet_shutdown(struct tb_service *svc)
1367	{
1368	tbnet_tear_down(net: tb_service_get_drvdata(svc), send_logout: true);
1369	}
1370
1371	static int tbnet_suspend(struct device *dev)
1372	{
1373	struct tb_service *svc = tb_to_service(dev);
1374	struct tbnet *net = tb_service_get_drvdata(svc);
1375
1376	stop_login(net);
1377	if (netif_running(dev: net->dev)) {
1378	netif_device_detach(dev: net->dev);
1379	tbnet_tear_down(net, send_logout: true);
1380	}
1381
1382	tb_unregister_protocol_handler(handler: &net->handler);
1383	return 0;
1384	}
1385
1386	static int tbnet_resume(struct device *dev)
1387	{
1388	struct tb_service *svc = tb_to_service(dev);
1389	struct tbnet *net = tb_service_get_drvdata(svc);
1390
1391	tb_register_protocol_handler(handler: &net->handler);
1392
1393	netif_carrier_off(dev: net->dev);
1394	if (netif_running(dev: net->dev)) {
1395	netif_device_attach(dev: net->dev);
1396	start_login(net);
1397	}
1398
1399	return 0;
1400	}
1401
1402	static DEFINE_SIMPLE_DEV_PM_OPS(tbnet_pm_ops, tbnet_suspend, tbnet_resume);
1403
1404	static const struct tb_service_id tbnet_ids[] = {
1405	{ TB_SERVICE("network", 1) },
1406	{ },
1407	};
1408	MODULE_DEVICE_TABLE(tbsvc, tbnet_ids);
1409
1410	static struct tb_service_driver tbnet_driver = {
1411	.driver = {
1412	.owner = THIS_MODULE,
1413	.name = "thunderbolt-net",
1414	.pm = pm_sleep_ptr(&tbnet_pm_ops),
1415	},
1416	.probe = tbnet_probe,
1417	.remove = tbnet_remove,
1418	.shutdown = tbnet_shutdown,
1419	.id_table = tbnet_ids,
1420	};
1421
1422	static int __init tbnet_init(void)
1423	{
1424	unsigned int flags;
1425	int ret;
1426
1427	tbnet_dir = tb_property_create_dir(uuid: &tbnet_dir_uuid);
1428	if (!tbnet_dir)
1429	return -ENOMEM;
1430
1431	tb_property_add_immediate(parent: tbnet_dir, key: "prtcid", value: 1);
1432	tb_property_add_immediate(parent: tbnet_dir, key: "prtcvers", value: 1);
1433	tb_property_add_immediate(parent: tbnet_dir, key: "prtcrevs", value: 1);
1434
1435	flags = TBNET_MATCH_FRAGS_ID | TBNET_64K_FRAMES;
1436	if (tbnet_e2e)
1437	flags |= TBNET_E2E;
1438	tb_property_add_immediate(parent: tbnet_dir, key: "prtcstns", value: flags);
1439
1440	ret = tb_register_property_dir(key: "network", dir: tbnet_dir);
1441	if (ret)
1442	goto err_free_dir;
1443
1444	ret = tb_register_service_driver(drv: &tbnet_driver);
1445	if (ret)
1446	goto err_unregister;
1447
1448	return 0;
1449
1450	err_unregister:
1451	tb_unregister_property_dir(key: "network", dir: tbnet_dir);
1452	err_free_dir:
1453	tb_property_free_dir(dir: tbnet_dir);
1454
1455	return ret;
1456	}
1457	module_init(tbnet_init);
1458
1459	static void __exit tbnet_exit(void)
1460	{
1461	tb_unregister_service_driver(drv: &tbnet_driver);
1462	tb_unregister_property_dir(key: "network", dir: tbnet_dir);
1463	tb_property_free_dir(dir: tbnet_dir);
1464	}
1465	module_exit(tbnet_exit);
1466
1467	MODULE_AUTHOR("Amir Levy <amir.jer.levy@intel.com>");
1468	MODULE_AUTHOR("Michael Jamet <michael.jamet@intel.com>");
1469	MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
1470	MODULE_DESCRIPTION("Thunderbolt/USB4 network driver");
1471	MODULE_LICENSE("GPL v2");
1472