drivers/net/thunderbolt/main.c

   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 <[email protected]>
   8  *          Michael Jamet <[email protected]>
   9  *          Mika Westerberg <[email protected]>
  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(&hdr->uuid, &tbnet_svc_uuid);
 234         uuid_copy(&hdr->initiator_uuid, initiator_uuid);
 235         uuid_copy(&hdr->target_uuid, 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(&reply.hdr, route, sequence, xd->local_uuid,
 248                           xd->remote_uuid, TBIP_LOGIN_RESPONSE, 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, &reply, sizeof(reply),
 254                                    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(&request.hdr, xd->route, sequence, xd->local_uuid,
 265                           xd->remote_uuid, TBIP_LOGIN, sizeof(request),
 266                           atomic_inc_return(&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, sizeof(request),
 272                                   TB_CFG_PKG_XDOMAIN_RESP, &reply,
 273                                   sizeof(reply), 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(&reply.hdr, route, sequence, xd->local_uuid,
 285                           xd->remote_uuid, TBIP_STATUS, sizeof(reply),
 286                           atomic_inc_return(&net->command_id));
 287         return tb_xdomain_response(xd, &reply, sizeof(reply),
 288                                    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(&request.hdr, xd->route, 0, xd->local_uuid,
 299                           xd->remote_uuid, TBIP_LOGOUT, sizeof(request),
 300                           atomic_inc_return(&net->command_id));
 301
 302         return tb_xdomain_request(xd, &request, sizeof(request),
 303                                   TB_CFG_PKG_XDOMAIN_RESP, &reply,
 304                                   sizeof(reply), 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(&net->connection_lock);
 316
 317         queue_delayed_work(system_long_wq, &net->login_work,
 318                            msecs_to_jiffies(1000));
 319 }
 320
 321 static void stop_login(struct tbnet *net)
 322 {
 323         cancel_delayed_work_sync(&net->login_work);
 324         cancel_work_sync(&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);
 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(i, tf->page, 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(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(net->dev);
 375         netif_stop_queue(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(net->rx_ring.ring);
 393                 tb_ring_stop(net->tx_ring.ring);
 394                 tbnet_free_buffers(&net->rx_ring);
 395                 tbnet_free_buffers(&net->tx_ring);
 396
 397                 ret = tb_xdomain_disable_paths(net->xd,
 398                                                net->local_transmit_path,
 399                                                net->rx_ring.ring->hop,
 400                                                net->remote_transmit_path,
 401                                                net->tx_ring.ring->hop);
 402                 if (ret)
 403                         netdev_warn(net->dev, "failed to disable DMA paths\n");
 404
 405                 tb_xdomain_release_in_hopid(net->xd, 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(&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(&pkg->hdr.initiator_uuid, net->xd->remote_uuid))
 431                 return 0;
 432         if (!uuid_equal(&pkg->hdr.target_uuid, 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(net->dev))
 448                         break;
 449
 450                 ret = tbnet_login_response(net, route, sequence,
 451                                            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(system_long_wq,
 467                                                    &net->login_work, 0);
 468                         }
 469                         mutex_unlock(&net->connection_lock);
 470
 471                         queue_work(system_long_wq, &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(system_long_wq, &net->disconnect_work);
 481                 }
 482                 break;
 483
 484         default:
 485                 return 0;
 486         }
 487
 488         if (ret)
 489                 netdev_warn(net->dev, "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);
 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(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, tf->page, dma_addr,
 534                                            DMA_FROM_DEVICE);
 535
 536                 tb_ring_rx(ring->ring, &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);
 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(dma_dev, tf->frame.buffer_phy,
 564                                 tbnet_frame_size(tf), 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(tf->dev);
 574
 575         /* Return buffer to the ring */
 576         net->tx_ring.prod++;
 577
 578         if (tbnet_available_buffers(&net->tx_ring) >= TBNET_RING_SIZE / 2)
 579                 netif_wake_queue(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);
 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(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(i, tf->page, dma_addr, 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(net->dev))
 629                 return;
 630
 631         mutex_lock(&net->connection_lock);
 632         connected = net->login_sent && net->login_received;
 633         mutex_unlock(&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(net->xd, net->remote_transmit_path);
 641         if (ret != net->remote_transmit_path) {
 642                 netdev_err(net->dev, "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(net->tx_ring.ring);
 654         tb_ring_start(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(net->xd, net->local_transmit_path,
 665                                       net->rx_ring.ring->hop,
 666                                       net->remote_transmit_path,
 667                                       net->tx_ring.ring->hop);
 668         if (ret) {
 669                 netdev_err(net->dev, "failed to enable DMA paths\n");
 670                 goto err_free_tx_buffers;
 671         }
 672
 673         netif_carrier_on(net->dev);
 674         netif_start_queue(net->dev);
 675
 676         netdev_dbg(net->dev, "network traffic started\n");
 677         return;
 678
 679 err_free_tx_buffers:
 680         tbnet_free_buffers(&net->tx_ring);
 681 err_free_rx_buffers:
 682         tbnet_free_buffers(&net->rx_ring);
 683 err_stop_rings:
 684         tb_ring_stop(net->rx_ring.ring);
 685         tb_ring_stop(net->tx_ring.ring);
 686         tb_xdomain_release_in_hopid(net->xd, 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(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, 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(system_long_wq, &net->login_work,
 707                                            delay);
 708                 } else {
 709                         netdev_info(net->dev, "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(&net->connection_lock);
 719
 720                 queue_work(system_long_wq, &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, 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(&net->rx_ring);
 806         struct device *dma_dev = tb_ring_dma_device(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, cleaned_count);
 825                         cleaned_count = 0;
 826                 }
 827
 828                 frame = tb_ring_poll(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(hdr->frame_size,
 845                                 hdr->frame_id, hdr->frame_index, hdr->frame_count);
 846                         __free_pages(page, TBNET_RX_PAGE_ORDER);
 847                         dev_kfree_skb_any(net->skb);
 848                         net->skb = NULL;
 849                         continue;
 850                 }
 851
 852                 trace_tbnet_rx_ip_frame(hdr->frame_size, hdr->frame_id,
 853                                         hdr->frame_index, 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, hdr_size);
 867                         skb_put(skb, frame_size);
 868
 869                         net->skb = skb;
 870                 } else {
 871                         skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
 872                                         page, hdr_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, net->dev);
 888                         trace_tbnet_rx_skb(skb);
 889                         napi_gro_receive(&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, cleaned_count);
 898
 899         if (rx_packets >= budget)
 900                 return budget;
 901
 902         napi_complete_done(napi, rx_packets);
 903         /* Re-enable the ring interrupt */
 904         tb_ring_poll_complete(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(&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(xd->tb->nhi, -1, TBNET_RING_SIZE,
 928                                 RING_FLAG_FRAME);
 929         if (!ring) {
 930                 netdev_err(dev, "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, -1);
 936         if (hopid < 0) {
 937                 netdev_err(dev, "failed to allocate Tx HopID\n");
 938                 tb_ring_free(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(xd->tb->nhi, -1, TBNET_RING_SIZE, flags,
 953                                 net->tx_ring.ring->hop, sof_mask,
 954                                 eof_mask, tbnet_start_poll, net);
 955         if (!ring) {
 956                 netdev_err(dev, "failed to allocate Rx ring\n");
 957                 tb_xdomain_release_out_hopid(xd, hopid);
 958                 tb_ring_free(net->tx_ring.ring);
 959                 net->tx_ring.ring = NULL;
 960                 return -ENOMEM;
 961         }
 962         net->rx_ring.ring = ring;
 963
 964         napi_enable(&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(&net->napi);
 975
 976         cancel_work_sync(&net->disconnect_work);
 977         tbnet_tear_down(net, true);
 978
 979         tb_ring_free(net->rx_ring.ring);
 980         net->rx_ring.ring = NULL;
 981
 982         tb_xdomain_release_out_hopid(net->xd, net->local_transmit_path);
 983         tb_ring_free(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(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(hdr->frame_size, hdr->frame_id,
1011                                                 hdr->frame_index, hdr->frame_count);
1012                         dma_sync_single_for_device(dma_dev,
1013                                 frames[i]->frame.buffer_phy,
1014                                 tbnet_frame_size(frames[i]), 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, sizeof(vh), &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(dest + skb_network_offset(skb),
1040                                       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(ip_hdr(skb)->saddr,
1050                                             ip_hdr(skb)->daddr, 0,
1051                                             ip_hdr(skb)->protocol, 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(&ipv6_hdr(skb)->saddr,
1055                                           &ipv6_hdr(skb)->daddr, 0,
1056                                           IPPROTO_TCP, 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(&ipv6_hdr(skb)->saddr,
1060                                           &ipv6_hdr(skb)->daddr, 0,
1061                                           ipv6_hdr(skb)->nexthdr, 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(dest, len, wsum);
1074                 hdr->frame_count = cpu_to_le32(frame_count);
1075                 trace_tbnet_tx_ip_frame(hdr->frame_size, hdr->frame_id,
1076                                         hdr->frame_index, hdr->frame_count);
1077
1078                 offset = 0;
1079         }
1080
1081         *tucso = csum_fold(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(dma_dev, frames[i]->frame.buffer_phy,
1088                         tbnet_frame_size(frames[i]), 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(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(&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(&net->tx_ring) < nframes) {
1123                 netif_stop_queue(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++, &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++, &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_index + 1))
1216                 goto err_drop;
1217
1218         for (i = 0; i < frame_index + 1; i++)
1219                 tb_ring_tx(net->tx_ring.ring, &frames[i]->frame);
1220
1221         if (net->svc->prtcstns & TBNET_MATCH_FRAGS_ID)
1222                 atomic_inc(&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((u32 *)xd->local_uuid, 4, 0);
1281         memcpy(addr + 1, &hash, sizeof(hash));
1282         hash = jhash2((u32 *)xd->local_uuid, 4, 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(&net->command_id, 0);
1306         atomic_set(&net->frame_id, 0);
1307         net->svc = svc;
1308         net->dev = dev;
1309         net->xd = xd;
1310
1311         tbnet_generate_mac(dev);
1312
1313         strcpy(dev->name, "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, &net->napi, 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(&net->handler);
1344
1345         tb_service_set_drvdata(svc, net);
1346
1347         ret = register_netdev(dev);
1348         if (ret) {
1349                 tb_unregister_protocol_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(net->dev);
1362         tb_unregister_protocol_handler(&net->handler);
1363         free_netdev(net->dev);
1364 }
1365
1366 static void tbnet_shutdown(struct tb_service *svc)
1367 {
1368         tbnet_tear_down(tb_service_get_drvdata(svc), 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(net->dev)) {
1378                 netif_device_detach(net->dev);
1379                 tbnet_tear_down(net, true);
1380         }
1381
1382         tb_unregister_protocol_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(&net->handler);
1392
1393         netif_carrier_off(net->dev);
1394         if (netif_running(net->dev)) {
1395                 netif_device_attach(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(&tbnet_dir_uuid);
1428         if (!tbnet_dir)
1429                 return -ENOMEM;
1430
1431         tb_property_add_immediate(tbnet_dir, "prtcid", 1);
1432         tb_property_add_immediate(tbnet_dir, "prtcvers", 1);
1433         tb_property_add_immediate(tbnet_dir, "prtcrevs", 1);
1434
1435         flags = TBNET_MATCH_FRAGS_ID | TBNET_64K_FRAMES;
1436         if (tbnet_e2e)
1437                 flags |= TBNET_E2E;
1438         tb_property_add_immediate(tbnet_dir, "prtcstns", flags);
1439
1440         ret = tb_register_property_dir("network", tbnet_dir);
1441         if (ret)
1442                 goto err_free_dir;
1443
1444         ret = tb_register_service_driver(&tbnet_driver);
1445         if (ret)
1446                 goto err_unregister;
1447
1448         return 0;
1449
1450 err_unregister:
1451         tb_unregister_property_dir("network", tbnet_dir);
1452 err_free_dir:
1453         tb_property_free_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(&tbnet_driver);
1462         tb_unregister_property_dir("network", tbnet_dir);
1463         tb_property_free_dir(tbnet_dir);
1464 }
1465 module_exit(tbnet_exit);
1466
1467 MODULE_AUTHOR("Amir Levy <[email protected]>");
1468 MODULE_AUTHOR("Michael Jamet <[email protected]>");
1469 MODULE_AUTHOR("Mika Westerberg <[email protected]>");
1470 MODULE_DESCRIPTION("Thunderbolt/USB4 network driver");
1471 MODULE_LICENSE("GPL v2");