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         set_bit(qid, vsi->af_xdp_zc_qps);
 106
 107         if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
 108
 109         if (if_running) {
 110                 err = i40e_queue_pair_disable(vsi, qid);
 111                 if (err)
 112                         return err;
 113
 114                 err = i40e_queue_pair_enable(vsi, qid);
 115                 if (err)
 116                         return err;
 117
 118                 /* Kick start the NAPI context so that receiving will start */
 119                 err = i40e_xsk_async_xmit(vsi->netdev, qid);
 120                 if (err)
 121                         return err;
 122         }
 123
 124         return 0;
 125 }
 126
 127 /**
 128  * i40e_xsk_umem_disable - Disassociate a UMEM from a certain ring/qid
 129  * @vsi: Current VSI
 130  * @qid: Rx ring to associate UMEM to
 131  *
 132  * Returns 0 on success, <0 on failure
 133  **/
 134 static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
 135 {
 136         struct net_device *netdev = vsi->netdev;
 137         struct xdp_umem *umem;
 138         bool if_running;
 139         int err;
 140
 141         umem = xdp_get_umem_from_qid(netdev, qid);
 142         if (!umem)
 143                 return -EINVAL;
 144
 145         if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
 146
 147         if (if_running) {
 148                 err = i40e_queue_pair_disable(vsi, qid);
 149                 if (err)
 150                         return err;
 151         }
 152
 153         clear_bit(qid, vsi->af_xdp_zc_qps);
 154         i40e_xsk_umem_dma_unmap(vsi, umem);
 155
 156         if (if_running) {
 157                 err = i40e_queue_pair_enable(vsi, qid);
 158                 if (err)
 159                         return err;
 160         }
 161
 162         return 0;
 163 }
 164
 165 /**
 166  * i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
 167  * @vsi: Current VSI
 168  * @umem: UMEM to enable/associate to a ring, or NULL to disable
 169  * @qid: Rx ring to (dis)associate UMEM (from)to
 170  *
 171  * This function enables or disables a UMEM to a certain ring.
 172  *
 173  * Returns 0 on success, <0 on failure
 174  **/
 175 int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
 176                         u16 qid)
 177 {
 178         return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
 179                 i40e_xsk_umem_disable(vsi, qid);
 180 }
 181
 182 /**
 183  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
 184  * @rx_ring: Rx ring
 185  * @xdp: xdp_buff used as input to the XDP program
 186  *
 187  * This function enables or disables a UMEM to a certain ring.
 188  *
 189  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
 190  **/
 191 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
 192 {
 193         int err, result = I40E_XDP_PASS;
 194         struct i40e_ring *xdp_ring;
 195         struct bpf_prog *xdp_prog;
 196         u32 act;
 197
 198         rcu_read_lock();
 199         /* NB! xdp_prog will always be !NULL, due to the fact that
 200          * this path is enabled by setting an XDP program.
 201          */
 202         xdp_prog = READ_ONCE(rx_ring->xdp_prog);
 203         act = bpf_prog_run_xdp(xdp_prog, xdp);
 204         xdp->handle += xdp->data - xdp->data_hard_start;
 205         switch (act) {
 206         case XDP_PASS:
 207                 break;
 208         case XDP_TX:
 209                 xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
 210                 result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
 211                 break;
 212         case XDP_REDIRECT:
 213                 err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 214                 result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
 215                 break;
 216         default:
 217                 bpf_warn_invalid_xdp_action(act);
 218         case XDP_ABORTED:
 219                 trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 220                 /* fallthrough -- handle aborts by dropping packet */
 221         case XDP_DROP:
 222                 result = I40E_XDP_CONSUMED;
 223                 break;
 224         }
 225         rcu_read_unlock();
 226         return result;
 227 }
 228
 229 /**
 230  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
 231  * @rx_ring: Rx ring
 232  * @bi: Rx buffer to populate
 233  *
 234  * This function allocates an Rx buffer. The buffer can come from fill
 235  * queue, or via the recycle queue (next_to_alloc).
 236  *
 237  * Returns true for a successful allocation, false otherwise
 238  **/
 239 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
 240                                  struct i40e_rx_buffer *bi)
 241 {
 242         struct xdp_umem *umem = rx_ring->xsk_umem;
 243         void *addr = bi->addr;
 244         u64 handle, hr;
 245
 246         if (addr) {
 247                 rx_ring->rx_stats.page_reuse_count++;
 248                 return true;
 249         }
 250
 251         if (!xsk_umem_peek_addr(umem, &handle)) {
 252                 rx_ring->rx_stats.alloc_page_failed++;
 253                 return false;
 254         }
 255
 256         hr = umem->headroom + XDP_PACKET_HEADROOM;
 257
 258         bi->dma = xdp_umem_get_dma(umem, handle);
 259         bi->dma += hr;
 260
 261         bi->addr = xdp_umem_get_data(umem, handle);
 262         bi->addr += hr;
 263
 264         bi->handle = handle + umem->headroom;
 265
 266         xsk_umem_discard_addr(umem);
 267         return true;
 268 }
 269
 270 /**
 271  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
 272  * @rx_ring: Rx ring
 273  * @bi: Rx buffer to populate
 274  *
 275  * This function allocates an Rx buffer. The buffer can come from fill
 276  * queue, or via the reuse queue.
 277  *
 278  * Returns true for a successful allocation, false otherwise
 279  **/
 280 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
 281                                       struct i40e_rx_buffer *bi)
 282 {
 283         struct xdp_umem *umem = rx_ring->xsk_umem;
 284         u64 handle, hr;
 285
 286         if (!xsk_umem_peek_addr_rq(umem, &handle)) {
 287                 rx_ring->rx_stats.alloc_page_failed++;
 288                 return false;
 289         }
 290
 291         handle &= rx_ring->xsk_umem->chunk_mask;
 292
 293         hr = umem->headroom + XDP_PACKET_HEADROOM;
 294
 295         bi->dma = xdp_umem_get_dma(umem, handle);
 296         bi->dma += hr;
 297
 298         bi->addr = xdp_umem_get_data(umem, handle);
 299         bi->addr += hr;
 300
 301         bi->handle = handle + umem->headroom;
 302
 303         xsk_umem_discard_addr_rq(umem);
 304         return true;
 305 }
 306
 307 static __always_inline bool
 308 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
 309                            bool alloc(struct i40e_ring *rx_ring,
 310                                       struct i40e_rx_buffer *bi))
 311 {
 312         u16 ntu = rx_ring->next_to_use;
 313         union i40e_rx_desc *rx_desc;
 314         struct i40e_rx_buffer *bi;
 315         bool ok = true;
 316
 317         rx_desc = I40E_RX_DESC(rx_ring, ntu);
 318         bi = &rx_ring->rx_bi[ntu];
 319         do {
 320                 if (!alloc(rx_ring, bi)) {
 321                         ok = false;
 322                         goto no_buffers;
 323                 }
 324
 325                 dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
 326                                                  rx_ring->rx_buf_len,
 327                                                  DMA_BIDIRECTIONAL);
 328
 329                 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
 330
 331                 rx_desc++;
 332                 bi++;
 333                 ntu++;
 334
 335                 if (unlikely(ntu == rx_ring->count)) {
 336                         rx_desc = I40E_RX_DESC(rx_ring, 0);
 337                         bi = rx_ring->rx_bi;
 338                         ntu = 0;
 339                 }
 340
 341                 rx_desc->wb.qword1.status_error_len = 0;
 342                 count--;
 343         } while (count);
 344
 345 no_buffers:
 346         if (rx_ring->next_to_use != ntu)
 347                 i40e_release_rx_desc(rx_ring, ntu);
 348
 349         return ok;
 350 }
 351
 352 /**
 353  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
 354  * @rx_ring: Rx ring
 355  * @count: The number of buffers to allocate
 356  *
 357  * This function allocates a number of Rx buffers from the reuse queue
 358  * or fill ring and places them on the Rx ring.
 359  *
 360  * Returns true for a successful allocation, false otherwise
 361  **/
 362 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
 363 {
 364         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 365                                           i40e_alloc_buffer_slow_zc);
 366 }
 367
 368 /**
 369  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
 370  * @rx_ring: Rx ring
 371  * @count: The number of buffers to allocate
 372  *
 373  * This function allocates a number of Rx buffers from the fill ring
 374  * or the internal recycle mechanism and places them on the Rx ring.
 375  *
 376  * Returns true for a successful allocation, false otherwise
 377  **/
 378 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
 379 {
 380         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 381                                           i40e_alloc_buffer_zc);
 382 }
 383
 384 /**
 385  * i40e_get_rx_buffer_zc - Return the current Rx buffer
 386  * @rx_ring: Rx ring
 387  * @size: The size of the rx buffer (read from descriptor)
 388  *
 389  * This function returns the current, received Rx buffer, and also
 390  * does DMA synchronization.  the Rx ring.
 391  *
 392  * Returns the received Rx buffer
 393  **/
 394 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
 395                                                     const unsigned int size)
 396 {
 397         struct i40e_rx_buffer *bi;
 398
 399         bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
 400
 401         /* we are reusing so sync this buffer for CPU use */
 402         dma_sync_single_range_for_cpu(rx_ring->dev,
 403                                       bi->dma, 0,
 404                                       size,
 405                                       DMA_BIDIRECTIONAL);
 406
 407         return bi;
 408 }
 409
 410 /**
 411  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
 412  * @rx_ring: Rx ring
 413  * @old_bi: The Rx buffer to recycle
 414  *
 415  * This function recycles a finished Rx buffer, and places it on the
 416  * recycle queue (next_to_alloc).
 417  **/
 418 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
 419                                     struct i40e_rx_buffer *old_bi)
 420 {
 421         struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
 422         unsigned long mask = (unsigned long)rx_ring->xsk_umem->chunk_mask;
 423         u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 424         u16 nta = rx_ring->next_to_alloc;
 425
 426         /* update, and store next to alloc */
 427         nta++;
 428         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 429
 430         /* transfer page from old buffer to new buffer */
 431         new_bi->dma = old_bi->dma & mask;
 432         new_bi->dma += hr;
 433
 434         new_bi->addr = (void *)((unsigned long)old_bi->addr & mask);
 435         new_bi->addr += hr;
 436
 437         new_bi->handle = old_bi->handle & mask;
 438         new_bi->handle += rx_ring->xsk_umem->headroom;
 439
 440         old_bi->addr = NULL;
 441 }
 442
 443 /**
 444  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
 445  * @alloc: Zero-copy allocator
 446  * @handle: Buffer handle
 447  **/
 448 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
 449 {
 450         struct i40e_rx_buffer *bi;
 451         struct i40e_ring *rx_ring;
 452         u64 hr, mask;
 453         u16 nta;
 454
 455         rx_ring = container_of(alloc, struct i40e_ring, zca);
 456         hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 457         mask = rx_ring->xsk_umem->chunk_mask;
 458
 459         nta = rx_ring->next_to_alloc;
 460         bi = &rx_ring->rx_bi[nta];
 461
 462         nta++;
 463         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 464
 465         handle &= mask;
 466
 467         bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
 468         bi->dma += hr;
 469
 470         bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
 471         bi->addr += hr;
 472
 473         bi->handle = (u64)handle + rx_ring->xsk_umem->headroom;
 474 }
 475
 476 /**
 477  * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
 478  * @rx_ring: Rx ring
 479  * @bi: Rx buffer
 480  * @xdp: xdp_buff
 481  *
 482  * This functions allocates a new skb from a zero-copy Rx buffer.
 483  *
 484  * Returns the skb, or NULL on failure.
 485  **/
 486 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
 487                                              struct i40e_rx_buffer *bi,
 488                                              struct xdp_buff *xdp)
 489 {
 490         unsigned int metasize = xdp->data - xdp->data_meta;
 491         unsigned int datasize = xdp->data_end - xdp->data;
 492         struct sk_buff *skb;
 493
 494         /* allocate a skb to store the frags */
 495         skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
 496                                xdp->data_end - xdp->data_hard_start,
 497                                GFP_ATOMIC | __GFP_NOWARN);
 498         if (unlikely(!skb))
 499                 return NULL;
 500
 501         skb_reserve(skb, xdp->data - xdp->data_hard_start);
 502         memcpy(__skb_put(skb, datasize), xdp->data, datasize);
 503         if (metasize)
 504                 skb_metadata_set(skb, metasize);
 505
 506         i40e_reuse_rx_buffer_zc(rx_ring, bi);
 507         return skb;
 508 }
 509
 510 /**
 511  * i40e_inc_ntc: Advance the next_to_clean index
 512  * @rx_ring: Rx ring
 513  **/
 514 static void i40e_inc_ntc(struct i40e_ring *rx_ring)
 515 {
 516         u32 ntc = rx_ring->next_to_clean + 1;
 517
 518         ntc = (ntc < rx_ring->count) ? ntc : 0;
 519         rx_ring->next_to_clean = ntc;
 520         prefetch(I40E_RX_DESC(rx_ring, ntc));
 521 }
 522
 523 /**
 524  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
 525  * @rx_ring: Rx ring
 526  * @budget: NAPI budget
 527  *
 528  * Returns amount of work completed
 529  **/
 530 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
 531 {
 532         unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 533         u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
 534         unsigned int xdp_res, xdp_xmit = 0;
 535         bool failure = false;
 536         struct sk_buff *skb;
 537         struct xdp_buff xdp;
 538
 539         xdp.rxq = &rx_ring->xdp_rxq;
 540
 541         while (likely(total_rx_packets < (unsigned int)budget)) {
 542                 struct i40e_rx_buffer *bi;
 543                 union i40e_rx_desc *rx_desc;
 544                 unsigned int size;
 545                 u64 qword;
 546
 547                 if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
 548                         failure = failure ||
 549                                   !i40e_alloc_rx_buffers_fast_zc(rx_ring,
 550                                                                  cleaned_count);
 551                         cleaned_count = 0;
 552                 }
 553
 554                 rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
 555                 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
 556
 557                 /* This memory barrier is needed to keep us from reading
 558                  * any other fields out of the rx_desc until we have
 559                  * verified the descriptor has been written back.
 560                  */
 561                 dma_rmb();
 562
 563                 bi = i40e_clean_programming_status(rx_ring, rx_desc,
 564                                                    qword);
 565                 if (unlikely(bi)) {
 566                         i40e_reuse_rx_buffer_zc(rx_ring, bi);
 567                         cleaned_count++;
 568                         continue;
 569                 }
 570
 571                 size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
 572                        I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
 573                 if (!size)
 574                         break;
 575
 576                 bi = i40e_get_rx_buffer_zc(rx_ring, size);
 577                 xdp.data = bi->addr;
 578                 xdp.data_meta = xdp.data;
 579                 xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
 580                 xdp.data_end = xdp.data + size;
 581                 xdp.handle = bi->handle;
 582
 583                 xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
 584                 if (xdp_res) {
 585                         if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
 586                                 xdp_xmit |= xdp_res;
 587                                 bi->addr = NULL;
 588                         } else {
 589                                 i40e_reuse_rx_buffer_zc(rx_ring, bi);
 590                         }
 591
 592                         total_rx_bytes += size;
 593                         total_rx_packets++;
 594
 595                         cleaned_count++;
 596                         i40e_inc_ntc(rx_ring);
 597                         continue;
 598                 }
 599
 600                 /* XDP_PASS path */
 601
 602                 /* NB! We are not checking for errors using
 603                  * i40e_test_staterr with
 604                  * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
 605                  * SBP is *not* set in PRT_SBPVSI (default not set).
 606                  */
 607                 skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
 608                 if (!skb) {
 609                         rx_ring->rx_stats.alloc_buff_failed++;
 610                         break;
 611                 }
 612
 613                 cleaned_count++;
 614                 i40e_inc_ntc(rx_ring);
 615
 616                 if (eth_skb_pad(skb))
 617                         continue;
 618
 619                 total_rx_bytes += skb->len;
 620                 total_rx_packets++;
 621
 622                 i40e_process_skb_fields(rx_ring, rx_desc, skb);
 623                 napi_gro_receive(&rx_ring->q_vector->napi, skb);
 624         }
 625
 626         i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
 627         i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
 628         return failure ? budget : (int)total_rx_packets;
 629 }
 630
 631 /**
 632  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
 633  * @xdp_ring: XDP Tx ring
 634  * @budget: NAPI budget
 635  *
 636  * Returns true if the work is finished.
 637  **/
 638 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 639 {
 640         struct i40e_tx_desc *tx_desc = NULL;
 641         struct i40e_tx_buffer *tx_bi;
 642         bool work_done = true;
 643         dma_addr_t dma;
 644         u32 len;
 645
 646         while (budget-- > 0) {
 647                 if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
 648                         xdp_ring->tx_stats.tx_busy++;
 649                         work_done = false;
 650                         break;
 651                 }
 652
 653                 if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &dma, &len))
 654                         break;
 655
 656                 dma_sync_single_for_device(xdp_ring->dev, dma, len,
 657                                            DMA_BIDIRECTIONAL);
 658
 659                 tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
 660                 tx_bi->bytecount = len;
 661
 662                 tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
 663                 tx_desc->buffer_addr = cpu_to_le64(dma);
 664                 tx_desc->cmd_type_offset_bsz =
 665                         build_ctob(I40E_TX_DESC_CMD_ICRC
 666                                    | I40E_TX_DESC_CMD_EOP,
 667                                    0, len, 0);
 668
 669                 xdp_ring->next_to_use++;
 670                 if (xdp_ring->next_to_use == xdp_ring->count)
 671                         xdp_ring->next_to_use = 0;
 672         }
 673
 674         if (tx_desc) {
 675                 /* Request an interrupt for the last frame and bump tail ptr. */
 676                 tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
 677                                                  I40E_TXD_QW1_CMD_SHIFT);
 678                 i40e_xdp_ring_update_tail(xdp_ring);
 679
 680                 xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
 681         }
 682
 683         return !!budget && work_done;
 684 }
 685
 686 /**
 687  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
 688  * @tx_ring: XDP Tx ring
 689  * @tx_bi: Tx buffer info to clean
 690  **/
 691 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
 692                                      struct i40e_tx_buffer *tx_bi)
 693 {
 694         xdp_return_frame(tx_bi->xdpf);
 695         dma_unmap_single(tx_ring->dev,
 696                          dma_unmap_addr(tx_bi, dma),
 697                          dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
 698         dma_unmap_len_set(tx_bi, len, 0);
 699 }
 700
 701 /**
 702  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
 703  * @tx_ring: XDP Tx ring
 704  * @tx_bi: Tx buffer info to clean
 705  *
 706  * Returns true if cleanup/tranmission is done.
 707  **/
 708 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
 709                            struct i40e_ring *tx_ring, int napi_budget)
 710 {
 711         unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
 712         u32 i, completed_frames, frames_ready, xsk_frames = 0;
 713         struct xdp_umem *umem = tx_ring->xsk_umem;
 714         u32 head_idx = i40e_get_head(tx_ring);
 715         bool work_done = true, xmit_done;
 716         struct i40e_tx_buffer *tx_bi;
 717
 718         if (head_idx < tx_ring->next_to_clean)
 719                 head_idx += tx_ring->count;
 720         frames_ready = head_idx - tx_ring->next_to_clean;
 721
 722         if (frames_ready == 0) {
 723                 goto out_xmit;
 724         } else if (frames_ready > budget) {
 725                 completed_frames = budget;
 726                 work_done = false;
 727         } else {
 728                 completed_frames = frames_ready;
 729         }
 730
 731         ntc = tx_ring->next_to_clean;
 732
 733         for (i = 0; i < completed_frames; i++) {
 734                 tx_bi = &tx_ring->tx_bi[ntc];
 735
 736                 if (tx_bi->xdpf)
 737                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 738                 else
 739                         xsk_frames++;
 740
 741                 tx_bi->xdpf = NULL;
 742                 total_bytes += tx_bi->bytecount;
 743
 744                 if (++ntc >= tx_ring->count)
 745                         ntc = 0;
 746         }
 747
 748         tx_ring->next_to_clean += completed_frames;
 749         if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
 750                 tx_ring->next_to_clean -= tx_ring->count;
 751
 752         if (xsk_frames)
 753                 xsk_umem_complete_tx(umem, xsk_frames);
 754
 755         i40e_arm_wb(tx_ring, vsi, budget);
 756         i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
 757
 758 out_xmit:
 759         xmit_done = i40e_xmit_zc(tx_ring, budget);
 760
 761         return work_done && xmit_done;
 762 }
 763
 764 /**
 765  * i40e_xsk_async_xmit - Implements the ndo_xsk_async_xmit
 766  * @dev: the netdevice
 767  * @queue_id: queue id to wake up
 768  *
 769  * Returns <0 for errors, 0 otherwise.
 770  **/
 771 int i40e_xsk_async_xmit(struct net_device *dev, u32 queue_id)
 772 {
 773         struct i40e_netdev_priv *np = netdev_priv(dev);
 774         struct i40e_vsi *vsi = np->vsi;
 775         struct i40e_ring *ring;
 776
 777         if (test_bit(__I40E_VSI_DOWN, vsi->state))
 778                 return -ENETDOWN;
 779
 780         if (!i40e_enabled_xdp_vsi(vsi))
 781                 return -ENXIO;
 782
 783         if (queue_id >= vsi->num_queue_pairs)
 784                 return -ENXIO;
 785
 786         if (!vsi->xdp_rings[queue_id]->xsk_umem)
 787                 return -ENXIO;
 788
 789         ring = vsi->xdp_rings[queue_id];
 790
 791         /* The idea here is that if NAPI is running, mark a miss, so
 792          * it will run again. If not, trigger an interrupt and
 793          * schedule the NAPI from interrupt context. If NAPI would be
 794          * scheduled here, the interrupt affinity would not be
 795          * honored.
 796          */
 797         if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
 798                 i40e_force_wb(vsi, ring->q_vector);
 799
 800         return 0;
 801 }
 802
 803 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
 804 {
 805         u16 i;
 806
 807         for (i = 0; i < rx_ring->count; i++) {
 808                 struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
 809
 810                 if (!rx_bi->addr)
 811                         continue;
 812
 813                 xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
 814                 rx_bi->addr = NULL;
 815         }
 816 }
 817
 818 /**
 819  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
 820  * @xdp_ring: XDP Tx ring
 821  **/
 822 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
 823 {
 824         u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
 825         struct xdp_umem *umem = tx_ring->xsk_umem;
 826         struct i40e_tx_buffer *tx_bi;
 827         u32 xsk_frames = 0;
 828
 829         while (ntc != ntu) {
 830                 tx_bi = &tx_ring->tx_bi[ntc];
 831
 832                 if (tx_bi->xdpf)
 833                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 834                 else
 835                         xsk_frames++;
 836
 837                 tx_bi->xdpf = NULL;
 838
 839                 ntc++;
 840                 if (ntc >= tx_ring->count)
 841                         ntc = 0;
 842         }
 843
 844         if (xsk_frames)
 845                 xsk_umem_complete_tx(umem, xsk_frames);
 846 }
 847
 848 /**
 849  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
 850  * @vsi: vsi
 851  *
 852  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
 853  **/
 854 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
 855 {
 856         struct net_device *netdev = vsi->netdev;
 857         int i;
 858
 859         for (i = 0; i < vsi->num_queue_pairs; i++) {
 860                 if (xdp_get_umem_from_qid(netdev, i))
 861                         return true;
 862         }
 863
 864         return false;
 865 }