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_wakeup(vsi->netdev, qid, XDP_WAKEUP_RX);
 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         struct xdp_umem *umem = rx_ring->xsk_umem;
 194         int err, result = I40E_XDP_PASS;
 195         struct i40e_ring *xdp_ring;
 196         struct bpf_prog *xdp_prog;
 197         u64 offset;
 198         u32 act;
 199
 200         rcu_read_lock();
 201         /* NB! xdp_prog will always be !NULL, due to the fact that
 202          * this path is enabled by setting an XDP program.
 203          */
 204         xdp_prog = READ_ONCE(rx_ring->xdp_prog);
 205         act = bpf_prog_run_xdp(xdp_prog, xdp);
 206         offset = xdp->data - xdp->data_hard_start;
 207
 208         xdp->handle = xsk_umem_adjust_offset(umem, xdp->handle, offset);
 209
 210         switch (act) {
 211         case XDP_PASS:
 212                 break;
 213         case XDP_TX:
 214                 xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
 215                 result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
 216                 break;
 217         case XDP_REDIRECT:
 218                 err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 219                 result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
 220                 break;
 221         default:
 222                 bpf_warn_invalid_xdp_action(act);
 223                 /* fall through */
 224         case XDP_ABORTED:
 225                 trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 226                 /* fallthrough -- handle aborts by dropping packet */
 227         case XDP_DROP:
 228                 result = I40E_XDP_CONSUMED;
 229                 break;
 230         }
 231         rcu_read_unlock();
 232         return result;
 233 }
 234
 235 /**
 236  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
 237  * @rx_ring: Rx ring
 238  * @bi: Rx buffer to populate
 239  *
 240  * This function allocates an Rx buffer. The buffer can come from fill
 241  * queue, or via the recycle queue (next_to_alloc).
 242  *
 243  * Returns true for a successful allocation, false otherwise
 244  **/
 245 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
 246                                  struct i40e_rx_buffer *bi)
 247 {
 248         struct xdp_umem *umem = rx_ring->xsk_umem;
 249         void *addr = bi->addr;
 250         u64 handle, hr;
 251
 252         if (addr) {
 253                 rx_ring->rx_stats.page_reuse_count++;
 254                 return true;
 255         }
 256
 257         if (!xsk_umem_peek_addr(umem, &handle)) {
 258                 rx_ring->rx_stats.alloc_page_failed++;
 259                 return false;
 260         }
 261
 262         hr = umem->headroom + XDP_PACKET_HEADROOM;
 263
 264         bi->dma = xdp_umem_get_dma(umem, handle);
 265         bi->dma += hr;
 266
 267         bi->addr = xdp_umem_get_data(umem, handle);
 268         bi->addr += hr;
 269
 270         bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
 271
 272         xsk_umem_release_addr(umem);
 273         return true;
 274 }
 275
 276 /**
 277  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
 278  * @rx_ring: Rx ring
 279  * @bi: Rx buffer to populate
 280  *
 281  * This function allocates an Rx buffer. The buffer can come from fill
 282  * queue, or via the reuse queue.
 283  *
 284  * Returns true for a successful allocation, false otherwise
 285  **/
 286 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
 287                                       struct i40e_rx_buffer *bi)
 288 {
 289         struct xdp_umem *umem = rx_ring->xsk_umem;
 290         u64 handle, hr;
 291
 292         if (!xsk_umem_peek_addr_rq(umem, &handle)) {
 293                 rx_ring->rx_stats.alloc_page_failed++;
 294                 return false;
 295         }
 296
 297         handle &= rx_ring->xsk_umem->chunk_mask;
 298
 299         hr = umem->headroom + XDP_PACKET_HEADROOM;
 300
 301         bi->dma = xdp_umem_get_dma(umem, handle);
 302         bi->dma += hr;
 303
 304         bi->addr = xdp_umem_get_data(umem, handle);
 305         bi->addr += hr;
 306
 307         bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
 308
 309         xsk_umem_release_addr_rq(umem);
 310         return true;
 311 }
 312
 313 static __always_inline bool
 314 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
 315                            bool alloc(struct i40e_ring *rx_ring,
 316                                       struct i40e_rx_buffer *bi))
 317 {
 318         u16 ntu = rx_ring->next_to_use;
 319         union i40e_rx_desc *rx_desc;
 320         struct i40e_rx_buffer *bi;
 321         bool ok = true;
 322
 323         rx_desc = I40E_RX_DESC(rx_ring, ntu);
 324         bi = &rx_ring->rx_bi[ntu];
 325         do {
 326                 if (!alloc(rx_ring, bi)) {
 327                         ok = false;
 328                         goto no_buffers;
 329                 }
 330
 331                 dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
 332                                                  rx_ring->rx_buf_len,
 333                                                  DMA_BIDIRECTIONAL);
 334
 335                 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
 336
 337                 rx_desc++;
 338                 bi++;
 339                 ntu++;
 340
 341                 if (unlikely(ntu == rx_ring->count)) {
 342                         rx_desc = I40E_RX_DESC(rx_ring, 0);
 343                         bi = rx_ring->rx_bi;
 344                         ntu = 0;
 345                 }
 346
 347                 rx_desc->wb.qword1.status_error_len = 0;
 348                 count--;
 349         } while (count);
 350
 351 no_buffers:
 352         if (rx_ring->next_to_use != ntu)
 353                 i40e_release_rx_desc(rx_ring, ntu);
 354
 355         return ok;
 356 }
 357
 358 /**
 359  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
 360  * @rx_ring: Rx ring
 361  * @count: The number of buffers to allocate
 362  *
 363  * This function allocates a number of Rx buffers from the reuse queue
 364  * or fill ring and places them on the Rx ring.
 365  *
 366  * Returns true for a successful allocation, false otherwise
 367  **/
 368 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
 369 {
 370         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 371                                           i40e_alloc_buffer_slow_zc);
 372 }
 373
 374 /**
 375  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
 376  * @rx_ring: Rx ring
 377  * @count: The number of buffers to allocate
 378  *
 379  * This function allocates a number of Rx buffers from the fill ring
 380  * or the internal recycle mechanism and places them on the Rx ring.
 381  *
 382  * Returns true for a successful allocation, false otherwise
 383  **/
 384 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
 385 {
 386         return __i40e_alloc_rx_buffers_zc(rx_ring, count,
 387                                           i40e_alloc_buffer_zc);
 388 }
 389
 390 /**
 391  * i40e_get_rx_buffer_zc - Return the current Rx buffer
 392  * @rx_ring: Rx ring
 393  * @size: The size of the rx buffer (read from descriptor)
 394  *
 395  * This function returns the current, received Rx buffer, and also
 396  * does DMA synchronization.  the Rx ring.
 397  *
 398  * Returns the received Rx buffer
 399  **/
 400 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
 401                                                     const unsigned int size)
 402 {
 403         struct i40e_rx_buffer *bi;
 404
 405         bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
 406
 407         /* we are reusing so sync this buffer for CPU use */
 408         dma_sync_single_range_for_cpu(rx_ring->dev,
 409                                       bi->dma, 0,
 410                                       size,
 411                                       DMA_BIDIRECTIONAL);
 412
 413         return bi;
 414 }
 415
 416 /**
 417  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
 418  * @rx_ring: Rx ring
 419  * @old_bi: The Rx buffer to recycle
 420  *
 421  * This function recycles a finished Rx buffer, and places it on the
 422  * recycle queue (next_to_alloc).
 423  **/
 424 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
 425                                     struct i40e_rx_buffer *old_bi)
 426 {
 427         struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
 428         u16 nta = rx_ring->next_to_alloc;
 429
 430         /* update, and store next to alloc */
 431         nta++;
 432         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 433
 434         /* transfer page from old buffer to new buffer */
 435         new_bi->dma = old_bi->dma;
 436         new_bi->addr = old_bi->addr;
 437         new_bi->handle = old_bi->handle;
 438
 439         old_bi->addr = NULL;
 440 }
 441
 442 /**
 443  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
 444  * @alloc: Zero-copy allocator
 445  * @handle: Buffer handle
 446  **/
 447 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
 448 {
 449         struct i40e_rx_buffer *bi;
 450         struct i40e_ring *rx_ring;
 451         u64 hr, mask;
 452         u16 nta;
 453
 454         rx_ring = container_of(alloc, struct i40e_ring, zca);
 455         hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 456         mask = rx_ring->xsk_umem->chunk_mask;
 457
 458         nta = rx_ring->next_to_alloc;
 459         bi = &rx_ring->rx_bi[nta];
 460
 461         nta++;
 462         rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 463
 464         handle &= mask;
 465
 466         bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
 467         bi->dma += hr;
 468
 469         bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
 470         bi->addr += hr;
 471
 472         bi->handle = xsk_umem_adjust_offset(rx_ring->xsk_umem, (u64)handle,
 473                                             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
 629         if (xsk_umem_uses_need_wakeup(rx_ring->xsk_umem)) {
 630                 if (failure || rx_ring->next_to_clean == rx_ring->next_to_use)
 631                         xsk_set_rx_need_wakeup(rx_ring->xsk_umem);
 632                 else
 633                         xsk_clear_rx_need_wakeup(rx_ring->xsk_umem);
 634
 635                 return (int)total_rx_packets;
 636         }
 637         return failure ? budget : (int)total_rx_packets;
 638 }
 639
 640 /**
 641  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
 642  * @xdp_ring: XDP Tx ring
 643  * @budget: NAPI budget
 644  *
 645  * Returns true if the work is finished.
 646  **/
 647 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 648 {
 649         struct i40e_tx_desc *tx_desc = NULL;
 650         struct i40e_tx_buffer *tx_bi;
 651         bool work_done = true;
 652         struct xdp_desc desc;
 653         dma_addr_t dma;
 654
 655         while (budget-- > 0) {
 656                 if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
 657                         xdp_ring->tx_stats.tx_busy++;
 658                         work_done = false;
 659                         break;
 660                 }
 661
 662                 if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &desc))
 663                         break;
 664
 665                 dma = xdp_umem_get_dma(xdp_ring->xsk_umem, desc.addr);
 666
 667                 dma_sync_single_for_device(xdp_ring->dev, dma, desc.len,
 668                                            DMA_BIDIRECTIONAL);
 669
 670                 tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
 671                 tx_bi->bytecount = desc.len;
 672
 673                 tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
 674                 tx_desc->buffer_addr = cpu_to_le64(dma);
 675                 tx_desc->cmd_type_offset_bsz =
 676                         build_ctob(I40E_TX_DESC_CMD_ICRC
 677                                    | I40E_TX_DESC_CMD_EOP,
 678                                    0, desc.len, 0);
 679
 680                 xdp_ring->next_to_use++;
 681                 if (xdp_ring->next_to_use == xdp_ring->count)
 682                         xdp_ring->next_to_use = 0;
 683         }
 684
 685         if (tx_desc) {
 686                 /* Request an interrupt for the last frame and bump tail ptr. */
 687                 tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
 688                                                  I40E_TXD_QW1_CMD_SHIFT);
 689                 i40e_xdp_ring_update_tail(xdp_ring);
 690
 691                 xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
 692         }
 693
 694         return !!budget && work_done;
 695 }
 696
 697 /**
 698  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
 699  * @tx_ring: XDP Tx ring
 700  * @tx_bi: Tx buffer info to clean
 701  **/
 702 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
 703                                      struct i40e_tx_buffer *tx_bi)
 704 {
 705         xdp_return_frame(tx_bi->xdpf);
 706         dma_unmap_single(tx_ring->dev,
 707                          dma_unmap_addr(tx_bi, dma),
 708                          dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
 709         dma_unmap_len_set(tx_bi, len, 0);
 710 }
 711
 712 /**
 713  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
 714  * @tx_ring: XDP Tx ring
 715  * @tx_bi: Tx buffer info to clean
 716  *
 717  * Returns true if cleanup/tranmission is done.
 718  **/
 719 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
 720                            struct i40e_ring *tx_ring, int napi_budget)
 721 {
 722         unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
 723         u32 i, completed_frames, frames_ready, xsk_frames = 0;
 724         struct xdp_umem *umem = tx_ring->xsk_umem;
 725         u32 head_idx = i40e_get_head(tx_ring);
 726         bool work_done = true, xmit_done;
 727         struct i40e_tx_buffer *tx_bi;
 728
 729         if (head_idx < tx_ring->next_to_clean)
 730                 head_idx += tx_ring->count;
 731         frames_ready = head_idx - tx_ring->next_to_clean;
 732
 733         if (frames_ready == 0) {
 734                 goto out_xmit;
 735         } else if (frames_ready > budget) {
 736                 completed_frames = budget;
 737                 work_done = false;
 738         } else {
 739                 completed_frames = frames_ready;
 740         }
 741
 742         ntc = tx_ring->next_to_clean;
 743
 744         for (i = 0; i < completed_frames; i++) {
 745                 tx_bi = &tx_ring->tx_bi[ntc];
 746
 747                 if (tx_bi->xdpf)
 748                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 749                 else
 750                         xsk_frames++;
 751
 752                 tx_bi->xdpf = NULL;
 753                 total_bytes += tx_bi->bytecount;
 754
 755                 if (++ntc >= tx_ring->count)
 756                         ntc = 0;
 757         }
 758
 759         tx_ring->next_to_clean += completed_frames;
 760         if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
 761                 tx_ring->next_to_clean -= tx_ring->count;
 762
 763         if (xsk_frames)
 764                 xsk_umem_complete_tx(umem, xsk_frames);
 765
 766         i40e_arm_wb(tx_ring, vsi, budget);
 767         i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
 768
 769 out_xmit:
 770         if (xsk_umem_uses_need_wakeup(tx_ring->xsk_umem))
 771                 xsk_set_tx_need_wakeup(tx_ring->xsk_umem);
 772
 773         xmit_done = i40e_xmit_zc(tx_ring, budget);
 774
 775         return work_done && xmit_done;
 776 }
 777
 778 /**
 779  * i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
 780  * @dev: the netdevice
 781  * @queue_id: queue id to wake up
 782  * @flags: ignored in our case since we have Rx and Tx in the same NAPI.
 783  *
 784  * Returns <0 for errors, 0 otherwise.
 785  **/
 786 int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
 787 {
 788         struct i40e_netdev_priv *np = netdev_priv(dev);
 789         struct i40e_vsi *vsi = np->vsi;
 790         struct i40e_pf *pf = vsi->back;
 791         struct i40e_ring *ring;
 792
 793         if (test_bit(__I40E_CONFIG_BUSY, pf->state))
 794                 return -EAGAIN;
 795
 796         if (test_bit(__I40E_VSI_DOWN, vsi->state))
 797                 return -ENETDOWN;
 798
 799         if (!i40e_enabled_xdp_vsi(vsi))
 800                 return -ENXIO;
 801
 802         if (queue_id >= vsi->num_queue_pairs)
 803                 return -ENXIO;
 804
 805         if (!vsi->xdp_rings[queue_id]->xsk_umem)
 806                 return -ENXIO;
 807
 808         ring = vsi->xdp_rings[queue_id];
 809
 810         /* The idea here is that if NAPI is running, mark a miss, so
 811          * it will run again. If not, trigger an interrupt and
 812          * schedule the NAPI from interrupt context. If NAPI would be
 813          * scheduled here, the interrupt affinity would not be
 814          * honored.
 815          */
 816         if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
 817                 i40e_force_wb(vsi, ring->q_vector);
 818
 819         return 0;
 820 }
 821
 822 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
 823 {
 824         u16 i;
 825
 826         for (i = 0; i < rx_ring->count; i++) {
 827                 struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
 828
 829                 if (!rx_bi->addr)
 830                         continue;
 831
 832                 xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
 833                 rx_bi->addr = NULL;
 834         }
 835 }
 836
 837 /**
 838  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
 839  * @xdp_ring: XDP Tx ring
 840  **/
 841 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
 842 {
 843         u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
 844         struct xdp_umem *umem = tx_ring->xsk_umem;
 845         struct i40e_tx_buffer *tx_bi;
 846         u32 xsk_frames = 0;
 847
 848         while (ntc != ntu) {
 849                 tx_bi = &tx_ring->tx_bi[ntc];
 850
 851                 if (tx_bi->xdpf)
 852                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 853                 else
 854                         xsk_frames++;
 855
 856                 tx_bi->xdpf = NULL;
 857
 858                 ntc++;
 859                 if (ntc >= tx_ring->count)
 860                         ntc = 0;
 861         }
 862
 863         if (xsk_frames)
 864                 xsk_umem_complete_tx(umem, xsk_frames);
 865 }
 866
 867 /**
 868  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
 869  * @vsi: vsi
 870  *
 871  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
 872  **/
 873 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
 874 {
 875         struct net_device *netdev = vsi->netdev;
 876         int i;
 877
 878         for (i = 0; i < vsi->num_queue_pairs; i++) {
 879                 if (xdp_get_umem_from_qid(netdev, i))
 880                         return true;
 881         }
 882
 883         return false;
 884 }