drivers/net/ethernet/intel/i40e/i40e_xsk.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright(c) 2018 Intel Corporation. */
   3
   4 #include <linux/bpf_trace.h>
   5 #include <net/xdp_sock.h>
   6 #include <net/xdp.h>
   7
   8 #include "i40e.h"
   9 #include "i40e_txrx_common.h"
  10 #include "i40e_xsk.h"
  11
  12 /**
  13  * i40e_xsk_umem_dma_map - DMA maps all UMEM memory for the netdev
  14  * @vsi: Current VSI
  15  * @umem: UMEM to DMA map
  16  *
  17  * Returns 0 on success, <0 on failure
  18  **/
  19 static int i40e_xsk_umem_dma_map(struct i40e_vsi *vsi, struct xdp_umem *umem)
  20 {
  21         struct i40e_pf *pf = vsi->back;
  22         struct device *dev;
  23         unsigned int i, j;
  24         dma_addr_t dma;
  25
  26         dev = &pf->pdev->dev;
  27         for (i = 0; i < umem->npgs; i++) {
  28                 dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
  29                                          DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
  30                 if (dma_mapping_error(dev, dma))
  31                         goto out_unmap;
  32
  33                 umem->pages[i].dma = dma;
  34         }
  35
  36         return 0;
  37
  38 out_unmap:
  39         for (j = 0; j < i; j++) {
  40                 dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
  41                                      DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
  42                 umem->pages[i].dma = 0;
  43         }
  44
  45         return -1;
  46 }
  47
  48 /**
  49  * i40e_xsk_umem_dma_unmap - DMA unmaps all UMEM memory for the netdev
  50  * @vsi: Current VSI
  51  * @umem: UMEM to DMA map
  52  **/
  53 static void i40e_xsk_umem_dma_unmap(struct i40e_vsi *vsi, struct xdp_umem *umem)
  54 {
  55         struct i40e_pf *pf = vsi->back;
  56         struct device *dev;
  57         unsigned int i;
  58
  59         dev = &pf->pdev->dev;
  60
  61         for (i = 0; i < umem->npgs; i++) {
  62                 dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
  63                                      DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
  64
  65                 umem->pages[i].dma = 0;
  66         }
  67 }
  68
  69 /**
  70  * i40e_xsk_umem_enable - Enable/associate a UMEM to a certain ring/qid
  71  * @vsi: Current VSI
  72  * @umem: UMEM
  73  * @qid: Rx ring to associate UMEM to
  74  *
  75  * Returns 0 on success, <0 on failure
  76  **/
  77 static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
  78                                 u16 qid)
  79 {
  80         struct net_device *netdev = vsi->netdev;
  81         struct xdp_umem_fq_reuse *reuseq;
  82         bool if_running;
  83         int err;
  84
  85         if (vsi->type != I40E_VSI_MAIN)
  86                 return -EINVAL;
  87
  88         if (qid >= vsi->num_queue_pairs)
  89                 return -EINVAL;
  90
  91         if (qid >= netdev->real_num_rx_queues ||
  92             qid >= netdev->real_num_tx_queues)
  93                 return -EINVAL;
  94
  95         reuseq = xsk_reuseq_prepare(vsi->rx_rings[0]->count);
  96         if (!reuseq)
  97                 return -ENOMEM;
  98
  99         xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
 100
 101         err = i40e_xsk_umem_dma_map(vsi, umem);
 102         if (err)
 103                 return err;
 104
 105         if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
 106
 107         if (if_running) {
 108                 err = i40e_queue_pair_disable(vsi, qid);
 109                 if (err)
 110                         return err;
 111
 112                 err = i40e_queue_pair_enable(vsi, qid);
 113                 if (err)
 114                         return err;
 115
 116                 /* Kick start the NAPI context so that receiving will start */
 117                 err = i40e_xsk_async_xmit(vsi->netdev, qid);
 118                 if (err)
 119                         return err;
 120         }
 121
 122         return 0;
 123 }
 124
 125 /**
 126  * i40e_xsk_umem_disable - Disassociate a UMEM from a certain ring/qid
 127  * @vsi: Current VSI
 128  * @qid: Rx ring to associate UMEM to
 129  *
 130  * Returns 0 on success, <0 on failure
 131  **/
 132 static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
 133 {
 134         struct net_device *netdev = vsi->netdev;
 135         struct xdp_umem *umem;
 136         bool if_running;
 137         int err;
 138
 139         umem = xdp_get_umem_from_qid(netdev, qid);
 140         if (!umem)
 141                 return -EINVAL;
 142
 143         if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
 144
 145         if (if_running) {
 146                 err = i40e_queue_pair_disable(vsi, qid);
 147                 if (err)
 148                         return err;
 149         }
 150
 151         i40e_xsk_umem_dma_unmap(vsi, umem);
 152
 153         if (if_running) {
 154                 err = i40e_queue_pair_enable(vsi, qid);
 155                 if (err)
 156                         return err;
 157         }
 158
 159         return 0;
 160 }
 161
 162 /**
 163  * i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
 164  * @vsi: Current VSI
 165  * @umem: UMEM to enable/associate to a ring, or NULL to disable
 166  * @qid: Rx ring to (dis)associate UMEM (from)to
 167  *
 168  * This function enables or disables a UMEM to a certain ring.
 169  *
 170  * Returns 0 on success, <0 on failure
 171  **/
 172 int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
 173                         u16 qid)
 174 {
 175         return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
 176                 i40e_xsk_umem_disable(vsi, qid);
 177 }
 178
 179 /**
 180  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
 181  * @rx_ring: Rx ring
 182  * @xdp: xdp_buff used as input to the XDP program
 183  *
 184  * This function enables or disables a UMEM to a certain ring.
 185  *
 186  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
 187  **/
 188 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
 189 {
 190         int err, result = I40E_XDP_PASS;
 191         struct i40e_ring *xdp_ring;
 192         struct bpf_prog *xdp_prog;
 193         u32 act;
 194
 195         rcu_read_lock();
 196         /* NB! xdp_prog will always be !NULL, due to the fact that
 197          * this path is enabled by setting an XDP program.
 198          */
 199         xdp_prog = READ_ONCE(rx_ring->xdp_prog);
 200         act = bpf_prog_run_xdp(xdp_prog, xdp);
 201         xdp->handle += xdp->data - xdp->data_hard_start;
 202         switch (act) {
 203         case XDP_PASS:
 204                 break;
 205         case XDP_TX:
 206                 xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
 207                 result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
 208                 break;
 209         case XDP_REDIRECT:
 210                 err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 211                 result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
 212                 break;
 213         default:
 214                 bpf_warn_invalid_xdp_action(act);
 215         case XDP_ABORTED:
 216                 trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 217                 /* fallthrough -- handle aborts by dropping packet */
 218         case XDP_DROP:
 219                 result = I40E_XDP_CONSUMED;
 220                 break;
 221         }
 222         rcu_read_unlock();
 223         return result;
 224 }
 225
 226 /**
 227  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
 228  * @rx_ring: Rx ring
 229  * @bi: Rx buffer to populate
 230  *
 231  * This function allocates an Rx buffer. The buffer can come from fill
 232  * queue, or via the recycle queue (next_to_alloc).
 233  *
 234  * Returns true for a successful allocation, false otherwise
 235  **/
 236 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
 237                                  struct i40e_rx_buffer *bi)
 238 {
 239         struct xdp_umem *umem = rx_ring->xsk_umem;
 240         void *addr = bi->addr;
 241         u64 handle, hr;
 242
 243         if (addr) {
 244                 rx_ring->rx_stats.page_reuse_count++;
 245                 return true;
 246         }
 247
 248         if (!xsk_umem_peek_addr(umem, &handle)) {
 249                 rx_ring->rx_stats.alloc_page_failed++;
 250                 return false;
 251         }
 252
 253         hr = umem->headroom + XDP_PACKET_HEADROOM;
 254
 255         bi->dma = xdp_umem_get_dma(umem, handle);
 256         bi->dma += hr;
 257
 258         bi->addr = xdp_umem_get_data(umem, handle);
 259         bi->addr += hr;
 260
 261         bi->handle = handle + umem->headroom;
 262
 263         xsk_umem_discard_addr(umem);
 264         return true;
 265 }
 266
 267 /**
 268  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
 269  * @rx_ring: Rx ring
 270  * @bi: Rx buffer to populate
 271  *
 272  * This function allocates an Rx buffer. The buffer can come from fill
 273  * queue, or via the reuse queue.
 274  *
 275  * Returns true for a successful allocation, false otherwise
 276  **/
 277 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
 278                                       struct i40e_rx_buffer *bi)
 279 {
 280         struct xdp_umem *umem = rx_ring->xsk_umem;
 281         u64 handle, hr;
 282
 283         if (!xsk_umem_peek_addr_rq(umem, &handle)) {
 284                 rx_ring->rx_stats.alloc_page_failed++;
 285                 return false;
 286         }
 287
 288         handle &= rx_ring->xsk_umem->chunk_mask;
 289
 290         hr = umem->headroom + XDP_PACKET_HEADROOM;
 291
 292         bi->dma = xdp_umem_get_dma(umem, handle);
 293         bi->dma += hr;
 294
 295         bi->addr = xdp_umem_get_data(umem, handle);
 296         bi->addr += hr;
 297
 298         bi->handle = handle + umem->headroom;
 299
 300         xsk_umem_discard_addr_rq(umem);
 301         return true;
 302 }
 303
 304 static __always_inline bool
 305 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
 306                            bool alloc(struct i40e_ring *rx_ring,
 307                                       struct i40e_rx_buffer *bi))
 308 {
 309         u16 ntu = rx_ring->next_to_use;
 310         union i40e_rx_desc *rx_desc;
 311         struct i40e_rx_buffer *bi;
 312         bool ok = true;
 313
 314         rx_desc = I40E_RX_DESC(rx_ring, ntu);
 315         bi = &rx_ring->rx_bi[ntu];
 316         do {
 317                 if (!alloc(rx_ring, bi)) {
 318                         ok = false;
 319                         goto no_buffers;
 320                 }
 321
 322                 dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
 323                                                  rx_ring->rx_buf_len,
 324                                                  DMA_BIDIRECTIONAL);
 325
 326                 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
 327
 328                 rx_desc++;
 329                 bi++;
 330                 ntu++;
 331
 332                 if (unlikely(ntu == rx_ring->count)) {
 333                         rx_desc = I40E_RX_DESC(rx_ring, 0);
 334                         bi = rx_ring->rx_bi;
 335                         ntu = 0;
 336                 }
 337
 338                 rx_desc->wb.qword1.status_error_len = 0;
 339                 count--;
 340         } while (count);
 341
 342 no_buffers:
 343         if (rx_ring->next_to_use != ntu)
 344                 i40e_release_rx_desc(rx_ring, ntu);
 345
 346         return ok;
 347 }
 348
 349 /**
 350  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
 351  * @rx_ring: Rx ring
 352  * @count: The number of buffers to allocate
 353  *
 354  * This function allocates a number of Rx buffers from the reuse queue
 355  * or fill ring and places them on the Rx ring.
 356  *
 357  * Returns true for a successful allocation, false otherwise
 358  **/
 359 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
 360 {
 361         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 362                                           i40e_alloc_buffer_slow_zc);
 363 }
 364
 365 /**
 366  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
 367  * @rx_ring: Rx ring
 368  * @count: The number of buffers to allocate
 369  *
 370  * This function allocates a number of Rx buffers from the fill ring
 371  * or the internal recycle mechanism and places them on the Rx ring.
 372  *
 373  * Returns true for a successful allocation, false otherwise
 374  **/
 375 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
 376 {
 377         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 378                                           i40e_alloc_buffer_zc);
 379 }
 380
 381 /**
 382  * i40e_get_rx_buffer_zc - Return the current Rx buffer
 383  * @rx_ring: Rx ring
 384  * @size: The size of the rx buffer (read from descriptor)
 385  *
 386  * This function returns the current, received Rx buffer, and also
 387  * does DMA synchronization.  the Rx ring.
 388  *
 389  * Returns the received Rx buffer
 390  **/
 391 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
 392                                                     const unsigned int size)
 393 {
 394         struct i40e_rx_buffer *bi;
 395
 396         bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
 397
 398         /* we are reusing so sync this buffer for CPU use */
 399         dma_sync_single_range_for_cpu(rx_ring->dev,
 400                                       bi->dma, 0,
 401                                       size,
 402                                       DMA_BIDIRECTIONAL);
 403
 404         return bi;
 405 }
 406
 407 /**
 408  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
 409  * @rx_ring: Rx ring
 410  * @old_bi: The Rx buffer to recycle
 411  *
 412  * This function recycles a finished Rx buffer, and places it on the
 413  * recycle queue (next_to_alloc).
 414  **/
 415 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
 416                                     struct i40e_rx_buffer *old_bi)
 417 {
 418         struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
 419         unsigned long mask = (unsigned long)rx_ring->xsk_umem->chunk_mask;
 420         u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 421         u16 nta = rx_ring->next_to_alloc;
 422
 423         /* update, and store next to alloc */
 424         nta++;
 425         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 426
 427         /* transfer page from old buffer to new buffer */
 428         new_bi->dma = old_bi->dma & mask;
 429         new_bi->dma += hr;
 430
 431         new_bi->addr = (void *)((unsigned long)old_bi->addr & mask);
 432         new_bi->addr += hr;
 433
 434         new_bi->handle = old_bi->handle & mask;
 435         new_bi->handle += rx_ring->xsk_umem->headroom;
 436
 437         old_bi->addr = NULL;
 438 }
 439
 440 /**
 441  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
 442  * @alloc: Zero-copy allocator
 443  * @handle: Buffer handle
 444  **/
 445 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
 446 {
 447         struct i40e_rx_buffer *bi;
 448         struct i40e_ring *rx_ring;
 449         u64 hr, mask;
 450         u16 nta;
 451
 452         rx_ring = container_of(alloc, struct i40e_ring, zca);
 453         hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 454         mask = rx_ring->xsk_umem->chunk_mask;
 455
 456         nta = rx_ring->next_to_alloc;
 457         bi = &rx_ring->rx_bi[nta];
 458
 459         nta++;
 460         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 461
 462         handle &= mask;
 463
 464         bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
 465         bi->dma += hr;
 466
 467         bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
 468         bi->addr += hr;
 469
 470         bi->handle = (u64)handle + rx_ring->xsk_umem->headroom;
 471 }
 472
 473 /**
 474  * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
 475  * @rx_ring: Rx ring
 476  * @bi: Rx buffer
 477  * @xdp: xdp_buff
 478  *
 479  * This functions allocates a new skb from a zero-copy Rx buffer.
 480  *
 481  * Returns the skb, or NULL on failure.
 482  **/
 483 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
 484                                              struct i40e_rx_buffer *bi,
 485                                              struct xdp_buff *xdp)
 486 {
 487         unsigned int metasize = xdp->data - xdp->data_meta;
 488         unsigned int datasize = xdp->data_end - xdp->data;
 489         struct sk_buff *skb;
 490
 491         /* allocate a skb to store the frags */
 492         skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
 493                                xdp->data_end - xdp->data_hard_start,
 494                                GFP_ATOMIC | __GFP_NOWARN);
 495         if (unlikely(!skb))
 496                 return NULL;
 497
 498         skb_reserve(skb, xdp->data - xdp->data_hard_start);
 499         memcpy(__skb_put(skb, datasize), xdp->data, datasize);
 500         if (metasize)
 501                 skb_metadata_set(skb, metasize);
 502
 503         i40e_reuse_rx_buffer_zc(rx_ring, bi);
 504         return skb;
 505 }
 506
 507 /**
 508  * i40e_inc_ntc: Advance the next_to_clean index
 509  * @rx_ring: Rx ring
 510  **/
 511 static void i40e_inc_ntc(struct i40e_ring *rx_ring)
 512 {
 513         u32 ntc = rx_ring->next_to_clean + 1;
 514
 515         ntc = (ntc < rx_ring->count) ? ntc : 0;
 516         rx_ring->next_to_clean = ntc;
 517         prefetch(I40E_RX_DESC(rx_ring, ntc));
 518 }
 519
 520 /**
 521  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
 522  * @rx_ring: Rx ring
 523  * @budget: NAPI budget
 524  *
 525  * Returns amount of work completed
 526  **/
 527 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
 528 {
 529         unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 530         u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
 531         unsigned int xdp_res, xdp_xmit = 0;
 532         bool failure = false;
 533         struct sk_buff *skb;
 534         struct xdp_buff xdp;
 535
 536         xdp.rxq = &rx_ring->xdp_rxq;
 537
 538         while (likely(total_rx_packets < (unsigned int)budget)) {
 539                 struct i40e_rx_buffer *bi;
 540                 union i40e_rx_desc *rx_desc;
 541                 unsigned int size;
 542                 u64 qword;
 543
 544                 if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
 545                         failure = failure ||
 546                                   !i40e_alloc_rx_buffers_fast_zc(rx_ring,
 547                                                                  cleaned_count);
 548                         cleaned_count = 0;
 549                 }
 550
 551                 rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
 552                 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
 553
 554                 /* This memory barrier is needed to keep us from reading
 555                  * any other fields out of the rx_desc until we have
 556                  * verified the descriptor has been written back.
 557                  */
 558                 dma_rmb();
 559
 560                 bi = i40e_clean_programming_status(rx_ring, rx_desc,
 561                                                    qword);
 562                 if (unlikely(bi)) {
 563                         i40e_reuse_rx_buffer_zc(rx_ring, bi);
 564                         cleaned_count++;
 565                         continue;
 566                 }
 567
 568                 size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
 569                        I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
 570                 if (!size)
 571                         break;
 572
 573                 bi = i40e_get_rx_buffer_zc(rx_ring, size);
 574                 xdp.data = bi->addr;
 575                 xdp.data_meta = xdp.data;
 576                 xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
 577                 xdp.data_end = xdp.data + size;
 578                 xdp.handle = bi->handle;
 579
 580                 xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
 581                 if (xdp_res) {
 582                         if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
 583                                 xdp_xmit |= xdp_res;
 584                                 bi->addr = NULL;
 585                         } else {
 586                                 i40e_reuse_rx_buffer_zc(rx_ring, bi);
 587                         }
 588
 589                         total_rx_bytes += size;
 590                         total_rx_packets++;
 591
 592                         cleaned_count++;
 593                         i40e_inc_ntc(rx_ring);
 594                         continue;
 595                 }
 596
 597                 /* XDP_PASS path */
 598
 599                 /* NB! We are not checking for errors using
 600                  * i40e_test_staterr with
 601                  * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
 602                  * SBP is *not* set in PRT_SBPVSI (default not set).
 603                  */
 604                 skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
 605                 if (!skb) {
 606                         rx_ring->rx_stats.alloc_buff_failed++;
 607                         break;
 608                 }
 609
 610                 cleaned_count++;
 611                 i40e_inc_ntc(rx_ring);
 612
 613                 if (eth_skb_pad(skb))
 614                         continue;
 615
 616                 total_rx_bytes += skb->len;
 617                 total_rx_packets++;
 618
 619                 i40e_process_skb_fields(rx_ring, rx_desc, skb);
 620                 napi_gro_receive(&rx_ring->q_vector->napi, skb);
 621         }
 622
 623         i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
 624         i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
 625         return failure ? budget : (int)total_rx_packets;
 626 }
 627
 628 /**
 629  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
 630  * @xdp_ring: XDP Tx ring
 631  * @budget: NAPI budget
 632  *
 633  * Returns true if the work is finished.
 634  **/
 635 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 636 {
 637         struct i40e_tx_desc *tx_desc = NULL;
 638         struct i40e_tx_buffer *tx_bi;
 639         bool work_done = true;
 640         dma_addr_t dma;
 641         u32 len;
 642
 643         while (budget-- > 0) {
 644                 if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
 645                         xdp_ring->tx_stats.tx_busy++;
 646                         work_done = false;
 647                         break;
 648                 }
 649
 650                 if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &dma, &len))
 651                         break;
 652
 653                 dma_sync_single_for_device(xdp_ring->dev, dma, len,
 654                                            DMA_BIDIRECTIONAL);
 655
 656                 tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
 657                 tx_bi->bytecount = len;
 658
 659                 tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
 660                 tx_desc->buffer_addr = cpu_to_le64(dma);
 661                 tx_desc->cmd_type_offset_bsz =
 662                         build_ctob(I40E_TX_DESC_CMD_ICRC
 663                                    | I40E_TX_DESC_CMD_EOP,
 664                                    0, len, 0);
 665
 666                 xdp_ring->next_to_use++;
 667                 if (xdp_ring->next_to_use == xdp_ring->count)
 668                         xdp_ring->next_to_use = 0;
 669         }
 670
 671         if (tx_desc) {
 672                 /* Request an interrupt for the last frame and bump tail ptr. */
 673                 tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
 674                                                  I40E_TXD_QW1_CMD_SHIFT);
 675                 i40e_xdp_ring_update_tail(xdp_ring);
 676
 677                 xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
 678         }
 679
 680         return !!budget && work_done;
 681 }
 682
 683 /**
 684  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
 685  * @tx_ring: XDP Tx ring
 686  * @tx_bi: Tx buffer info to clean
 687  **/
 688 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
 689                                      struct i40e_tx_buffer *tx_bi)
 690 {
 691         xdp_return_frame(tx_bi->xdpf);
 692         dma_unmap_single(tx_ring->dev,
 693                          dma_unmap_addr(tx_bi, dma),
 694                          dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
 695         dma_unmap_len_set(tx_bi, len, 0);
 696 }
 697
 698 /**
 699  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
 700  * @tx_ring: XDP Tx ring
 701  * @tx_bi: Tx buffer info to clean
 702  *
 703  * Returns true if cleanup/tranmission is done.
 704  **/
 705 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
 706                            struct i40e_ring *tx_ring, int napi_budget)
 707 {
 708         unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
 709         u32 i, completed_frames, frames_ready, xsk_frames = 0;
 710         struct xdp_umem *umem = tx_ring->xsk_umem;
 711         u32 head_idx = i40e_get_head(tx_ring);
 712         bool work_done = true, xmit_done;
 713         struct i40e_tx_buffer *tx_bi;
 714
 715         if (head_idx < tx_ring->next_to_clean)
 716                 head_idx += tx_ring->count;
 717         frames_ready = head_idx - tx_ring->next_to_clean;
 718
 719         if (frames_ready == 0) {
 720                 goto out_xmit;
 721         } else if (frames_ready > budget) {
 722                 completed_frames = budget;
 723                 work_done = false;
 724         } else {
 725                 completed_frames = frames_ready;
 726         }
 727
 728         ntc = tx_ring->next_to_clean;
 729
 730         for (i = 0; i < completed_frames; i++) {
 731                 tx_bi = &tx_ring->tx_bi[ntc];
 732
 733                 if (tx_bi->xdpf)
 734                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 735                 else
 736                         xsk_frames++;
 737
 738                 tx_bi->xdpf = NULL;
 739                 total_bytes += tx_bi->bytecount;
 740
 741                 if (++ntc >= tx_ring->count)
 742                         ntc = 0;
 743         }
 744
 745         tx_ring->next_to_clean += completed_frames;
 746         if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
 747                 tx_ring->next_to_clean -= tx_ring->count;
 748
 749         if (xsk_frames)
 750                 xsk_umem_complete_tx(umem, xsk_frames);
 751
 752         i40e_arm_wb(tx_ring, vsi, budget);
 753         i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
 754
 755 out_xmit:
 756         xmit_done = i40e_xmit_zc(tx_ring, budget);
 757
 758         return work_done && xmit_done;
 759 }
 760
 761 /**
 762  * i40e_xsk_async_xmit - Implements the ndo_xsk_async_xmit
 763  * @dev: the netdevice
 764  * @queue_id: queue id to wake up
 765  *
 766  * Returns <0 for errors, 0 otherwise.
 767  **/
 768 int i40e_xsk_async_xmit(struct net_device *dev, u32 queue_id)
 769 {
 770         struct i40e_netdev_priv *np = netdev_priv(dev);
 771         struct i40e_vsi *vsi = np->vsi;
 772         struct i40e_ring *ring;
 773
 774         if (test_bit(__I40E_VSI_DOWN, vsi->state))
 775                 return -ENETDOWN;
 776
 777         if (!i40e_enabled_xdp_vsi(vsi))
 778                 return -ENXIO;
 779
 780         if (queue_id >= vsi->num_queue_pairs)
 781                 return -ENXIO;
 782
 783         if (!vsi->xdp_rings[queue_id]->xsk_umem)
 784                 return -ENXIO;
 785
 786         ring = vsi->xdp_rings[queue_id];
 787
 788         /* The idea here is that if NAPI is running, mark a miss, so
 789          * it will run again. If not, trigger an interrupt and
 790          * schedule the NAPI from interrupt context. If NAPI would be
 791          * scheduled here, the interrupt affinity would not be
 792          * honored.
 793          */
 794         if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
 795                 i40e_force_wb(vsi, ring->q_vector);
 796
 797         return 0;
 798 }
 799
 800 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
 801 {
 802         u16 i;
 803
 804         for (i = 0; i < rx_ring->count; i++) {
 805                 struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
 806
 807                 if (!rx_bi->addr)
 808                         continue;
 809
 810                 xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
 811                 rx_bi->addr = NULL;
 812         }
 813 }
 814
 815 /**
 816  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
 817  * @xdp_ring: XDP Tx ring
 818  **/
 819 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
 820 {
 821         u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
 822         struct xdp_umem *umem = tx_ring->xsk_umem;
 823         struct i40e_tx_buffer *tx_bi;
 824         u32 xsk_frames = 0;
 825
 826         while (ntc != ntu) {
 827                 tx_bi = &tx_ring->tx_bi[ntc];
 828
 829                 if (tx_bi->xdpf)
 830                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 831                 else
 832                         xsk_frames++;
 833
 834                 tx_bi->xdpf = NULL;
 835
 836                 ntc++;
 837                 if (ntc >= tx_ring->count)
 838                         ntc = 0;
 839         }
 840
 841         if (xsk_frames)
 842                 xsk_umem_complete_tx(umem, xsk_frames);
 843 }
 844
 845 /**
 846  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
 847  * @vsi: vsi
 848  *
 849  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
 850  **/
 851 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
 852 {
 853         struct net_device *netdev = vsi->netdev;
 854         int i;
 855
 856         for (i = 0; i < vsi->num_queue_pairs; i++) {
 857                 if (xdp_get_umem_from_qid(netdev, i))
 858                         return true;
 859         }
 860
 861         return false;
 862 }