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