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_drv.h>
   6 #include "i40e_txrx_common.h"
   7 #include "i40e_xsk.h"
   8
   9 void i40e_clear_rx_bi_zc(struct i40e_ring *rx_ring)
  10 {
  11         memset(rx_ring->rx_bi_zc, 0,
  12                sizeof(*rx_ring->rx_bi_zc) * rx_ring->count);
  13 }
  14
  15 static struct xdp_buff **i40e_rx_bi(struct i40e_ring *rx_ring, u32 idx)
  16 {
  17         return &rx_ring->rx_bi_zc[idx];
  18 }
  19
  20 /**
  21  * i40e_realloc_rx_xdp_bi - reallocate SW ring for either XSK or normal buffer
  22  * @rx_ring: Current rx ring
  23  * @pool_present: is pool for XSK present
  24  *
  25  * Try allocating memory and return ENOMEM, if failed to allocate.
  26  * If allocation was successful, substitute buffer with allocated one.
  27  * Returns 0 on success, negative on failure
  28  */
  29 static int i40e_realloc_rx_xdp_bi(struct i40e_ring *rx_ring, bool pool_present)
  30 {
  31         size_t elem_size = pool_present ? sizeof(*rx_ring->rx_bi_zc) :
  32                                           sizeof(*rx_ring->rx_bi);
  33         void *sw_ring = kcalloc(rx_ring->count, elem_size, GFP_KERNEL);
  34
  35         if (!sw_ring)
  36                 return -ENOMEM;
  37
  38         if (pool_present) {
  39                 kfree(rx_ring->rx_bi);
  40                 rx_ring->rx_bi = NULL;
  41                 rx_ring->rx_bi_zc = sw_ring;
  42         } else {
  43                 kfree(rx_ring->rx_bi_zc);
  44                 rx_ring->rx_bi_zc = NULL;
  45                 rx_ring->rx_bi = sw_ring;
  46         }
  47         return 0;
  48 }
  49
  50 /**
  51  * i40e_realloc_rx_bi_zc - reallocate rx SW rings
  52  * @vsi: Current VSI
  53  * @zc: is zero copy set
  54  *
  55  * Reallocate buffer for rx_rings that might be used by XSK.
  56  * XDP requires more memory, than rx_buf provides.
  57  * Returns 0 on success, negative on failure
  58  */
  59 int i40e_realloc_rx_bi_zc(struct i40e_vsi *vsi, bool zc)
  60 {
  61         struct i40e_ring *rx_ring;
  62         unsigned long q;
  63
  64         for_each_set_bit(q, vsi->af_xdp_zc_qps, vsi->alloc_queue_pairs) {
  65                 rx_ring = vsi->rx_rings[q];
  66                 if (i40e_realloc_rx_xdp_bi(rx_ring, zc))
  67                         return -ENOMEM;
  68         }
  69         return 0;
  70 }
  71
  72 /**
  73  * i40e_xsk_pool_enable - Enable/associate an AF_XDP buffer pool to a
  74  * certain ring/qid
  75  * @vsi: Current VSI
  76  * @pool: buffer pool
  77  * @qid: Rx ring to associate buffer pool with
  78  *
  79  * Returns 0 on success, <0 on failure
  80  **/
  81 static int i40e_xsk_pool_enable(struct i40e_vsi *vsi,
  82                                 struct xsk_buff_pool *pool,
  83                                 u16 qid)
  84 {
  85         struct net_device *netdev = vsi->netdev;
  86         bool if_running;
  87         int err;
  88
  89         if (vsi->type != I40E_VSI_MAIN)
  90                 return -EINVAL;
  91
  92         if (qid >= vsi->num_queue_pairs)
  93                 return -EINVAL;
  94
  95         if (qid >= netdev->real_num_rx_queues ||
  96             qid >= netdev->real_num_tx_queues)
  97                 return -EINVAL;
  98
  99         err = xsk_pool_dma_map(pool, &vsi->back->pdev->dev, I40E_RX_DMA_ATTR);
 100         if (err)
 101                 return err;
 102
 103         set_bit(qid, vsi->af_xdp_zc_qps);
 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_realloc_rx_xdp_bi(vsi->rx_rings[qid], true);
 113                 if (err)
 114                         return err;
 115
 116                 err = i40e_queue_pair_enable(vsi, qid);
 117                 if (err)
 118                         return err;
 119
 120                 /* Kick start the NAPI context so that receiving will start */
 121                 err = i40e_xsk_wakeup(vsi->netdev, qid, XDP_WAKEUP_RX);
 122                 if (err)
 123                         return err;
 124         }
 125
 126         return 0;
 127 }
 128
 129 /**
 130  * i40e_xsk_pool_disable - Disassociate an AF_XDP buffer pool from a
 131  * certain ring/qid
 132  * @vsi: Current VSI
 133  * @qid: Rx ring to associate buffer pool with
 134  *
 135  * Returns 0 on success, <0 on failure
 136  **/
 137 static int i40e_xsk_pool_disable(struct i40e_vsi *vsi, u16 qid)
 138 {
 139         struct net_device *netdev = vsi->netdev;
 140         struct xsk_buff_pool *pool;
 141         bool if_running;
 142         int err;
 143
 144         pool = xsk_get_pool_from_qid(netdev, qid);
 145         if (!pool)
 146                 return -EINVAL;
 147
 148         if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
 149
 150         if (if_running) {
 151                 err = i40e_queue_pair_disable(vsi, qid);
 152                 if (err)
 153                         return err;
 154         }
 155
 156         clear_bit(qid, vsi->af_xdp_zc_qps);
 157         xsk_pool_dma_unmap(pool, I40E_RX_DMA_ATTR);
 158
 159         if (if_running) {
 160                 err = i40e_realloc_rx_xdp_bi(vsi->rx_rings[qid], false);
 161                 if (err)
 162                         return err;
 163                 err = i40e_queue_pair_enable(vsi, qid);
 164                 if (err)
 165                         return err;
 166         }
 167
 168         return 0;
 169 }
 170
 171 /**
 172  * i40e_xsk_pool_setup - Enable/disassociate an AF_XDP buffer pool to/from
 173  * a ring/qid
 174  * @vsi: Current VSI
 175  * @pool: Buffer pool to enable/associate to a ring, or NULL to disable
 176  * @qid: Rx ring to (dis)associate buffer pool (from)to
 177  *
 178  * This function enables or disables a buffer pool to a certain ring.
 179  *
 180  * Returns 0 on success, <0 on failure
 181  **/
 182 int i40e_xsk_pool_setup(struct i40e_vsi *vsi, struct xsk_buff_pool *pool,
 183                         u16 qid)
 184 {
 185         return pool ? i40e_xsk_pool_enable(vsi, pool, qid) :
 186                 i40e_xsk_pool_disable(vsi, qid);
 187 }
 188
 189 /**
 190  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
 191  * @rx_ring: Rx ring
 192  * @xdp: xdp_buff used as input to the XDP program
 193  * @xdp_prog: XDP program to run
 194  *
 195  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
 196  **/
 197 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp,
 198                            struct bpf_prog *xdp_prog)
 199 {
 200         int err, result = I40E_XDP_PASS;
 201         struct i40e_ring *xdp_ring;
 202         u32 act;
 203
 204         act = bpf_prog_run_xdp(xdp_prog, xdp);
 205
 206         if (likely(act == XDP_REDIRECT)) {
 207                 err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 208                 if (!err)
 209                         return I40E_XDP_REDIR;
 210                 if (xsk_uses_need_wakeup(rx_ring->xsk_pool) && err == -ENOBUFS)
 211                         result = I40E_XDP_EXIT;
 212                 else
 213                         result = I40E_XDP_CONSUMED;
 214                 goto out_failure;
 215         }
 216
 217         switch (act) {
 218         case XDP_PASS:
 219                 break;
 220         case XDP_TX:
 221                 xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
 222                 result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
 223                 if (result == I40E_XDP_CONSUMED)
 224                         goto out_failure;
 225                 break;
 226         case XDP_DROP:
 227                 result = I40E_XDP_CONSUMED;
 228                 break;
 229         default:
 230                 bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 231                 fallthrough;
 232         case XDP_ABORTED:
 233                 result = I40E_XDP_CONSUMED;
 234 out_failure:
 235                 trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 236         }
 237         return result;
 238 }
 239
 240 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
 241 {
 242         u16 ntu = rx_ring->next_to_use;
 243         union i40e_rx_desc *rx_desc;
 244         struct xdp_buff **xdp;
 245         u32 nb_buffs, i;
 246         dma_addr_t dma;
 247
 248         rx_desc = I40E_RX_DESC(rx_ring, ntu);
 249         xdp = i40e_rx_bi(rx_ring, ntu);
 250
 251         nb_buffs = min_t(u16, count, rx_ring->count - ntu);
 252         nb_buffs = xsk_buff_alloc_batch(rx_ring->xsk_pool, xdp, nb_buffs);
 253         if (!nb_buffs)
 254                 return false;
 255
 256         i = nb_buffs;
 257         while (i--) {
 258                 dma = xsk_buff_xdp_get_dma(*xdp);
 259                 rx_desc->read.pkt_addr = cpu_to_le64(dma);
 260                 rx_desc->read.hdr_addr = 0;
 261
 262                 rx_desc++;
 263                 xdp++;
 264         }
 265
 266         ntu += nb_buffs;
 267         if (ntu == rx_ring->count) {
 268                 rx_desc = I40E_RX_DESC(rx_ring, 0);
 269                 ntu = 0;
 270         }
 271
 272         /* clear the status bits for the next_to_use descriptor */
 273         rx_desc->wb.qword1.status_error_len = 0;
 274         i40e_release_rx_desc(rx_ring, ntu);
 275
 276         return count == nb_buffs;
 277 }
 278
 279 /**
 280  * i40e_construct_skb_zc - Create skbuff from zero-copy Rx buffer
 281  * @rx_ring: Rx ring
 282  * @xdp: xdp_buff
 283  *
 284  * This functions allocates a new skb from a zero-copy Rx buffer.
 285  *
 286  * Returns the skb, or NULL on failure.
 287  **/
 288 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
 289                                              struct xdp_buff *xdp)
 290 {
 291         unsigned int totalsize = xdp->data_end - xdp->data_meta;
 292         unsigned int metasize = xdp->data - xdp->data_meta;
 293         struct skb_shared_info *sinfo = NULL;
 294         struct sk_buff *skb;
 295         u32 nr_frags = 0;
 296
 297         if (unlikely(xdp_buff_has_frags(xdp))) {
 298                 sinfo = xdp_get_shared_info_from_buff(xdp);
 299                 nr_frags = sinfo->nr_frags;
 300         }
 301         net_prefetch(xdp->data_meta);
 302
 303         /* allocate a skb to store the frags */
 304         skb = __napi_alloc_skb(&rx_ring->q_vector->napi, totalsize,
 305                                GFP_ATOMIC | __GFP_NOWARN);
 306         if (unlikely(!skb))
 307                 goto out;
 308
 309         memcpy(__skb_put(skb, totalsize), xdp->data_meta,
 310                ALIGN(totalsize, sizeof(long)));
 311
 312         if (metasize) {
 313                 skb_metadata_set(skb, metasize);
 314                 __skb_pull(skb, metasize);
 315         }
 316
 317         if (likely(!xdp_buff_has_frags(xdp)))
 318                 goto out;
 319
 320         for (int i = 0; i < nr_frags; i++) {
 321                 struct skb_shared_info *skinfo = skb_shinfo(skb);
 322                 skb_frag_t *frag = &sinfo->frags[i];
 323                 struct page *page;
 324                 void *addr;
 325
 326                 page = dev_alloc_page();
 327                 if (!page) {
 328                         dev_kfree_skb(skb);
 329                         return NULL;
 330                 }
 331                 addr = page_to_virt(page);
 332
 333                 memcpy(addr, skb_frag_page(frag), skb_frag_size(frag));
 334
 335                 __skb_fill_page_desc_noacc(skinfo, skinfo->nr_frags++,
 336                                            addr, 0, skb_frag_size(frag));
 337         }
 338
 339 out:
 340         xsk_buff_free(xdp);
 341         return skb;
 342 }
 343
 344 static void i40e_handle_xdp_result_zc(struct i40e_ring *rx_ring,
 345                                       struct xdp_buff *xdp_buff,
 346                                       union i40e_rx_desc *rx_desc,
 347                                       unsigned int *rx_packets,
 348                                       unsigned int *rx_bytes,
 349                                       unsigned int xdp_res,
 350                                       bool *failure)
 351 {
 352         struct sk_buff *skb;
 353
 354         *rx_packets = 1;
 355         *rx_bytes = xdp_get_buff_len(xdp_buff);
 356
 357         if (likely(xdp_res == I40E_XDP_REDIR) || xdp_res == I40E_XDP_TX)
 358                 return;
 359
 360         if (xdp_res == I40E_XDP_EXIT) {
 361                 *failure = true;
 362                 return;
 363         }
 364
 365         if (xdp_res == I40E_XDP_CONSUMED) {
 366                 xsk_buff_free(xdp_buff);
 367                 return;
 368         }
 369         if (xdp_res == I40E_XDP_PASS) {
 370                 /* NB! We are not checking for errors using
 371                  * i40e_test_staterr with
 372                  * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
 373                  * SBP is *not* set in PRT_SBPVSI (default not set).
 374                  */
 375                 skb = i40e_construct_skb_zc(rx_ring, xdp_buff);
 376                 if (!skb) {
 377                         rx_ring->rx_stats.alloc_buff_failed++;
 378                         *rx_packets = 0;
 379                         *rx_bytes = 0;
 380                         return;
 381                 }
 382
 383                 if (eth_skb_pad(skb)) {
 384                         *rx_packets = 0;
 385                         *rx_bytes = 0;
 386                         return;
 387                 }
 388
 389                 i40e_process_skb_fields(rx_ring, rx_desc, skb);
 390                 napi_gro_receive(&rx_ring->q_vector->napi, skb);
 391                 return;
 392         }
 393
 394         /* Should never get here, as all valid cases have been handled already.
 395          */
 396         WARN_ON_ONCE(1);
 397 }
 398
 399 static int
 400 i40e_add_xsk_frag(struct i40e_ring *rx_ring, struct xdp_buff *first,
 401                   struct xdp_buff *xdp, const unsigned int size)
 402 {
 403         struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(first);
 404
 405         if (!xdp_buff_has_frags(first)) {
 406                 sinfo->nr_frags = 0;
 407                 sinfo->xdp_frags_size = 0;
 408                 xdp_buff_set_frags_flag(first);
 409         }
 410
 411         if (unlikely(sinfo->nr_frags == MAX_SKB_FRAGS)) {
 412                 xsk_buff_free(first);
 413                 return -ENOMEM;
 414         }
 415
 416         __skb_fill_page_desc_noacc(sinfo, sinfo->nr_frags++,
 417                                    virt_to_page(xdp->data_hard_start),
 418                                    XDP_PACKET_HEADROOM, size);
 419         sinfo->xdp_frags_size += size;
 420         xsk_buff_add_frag(xdp);
 421
 422         return 0;
 423 }
 424
 425 /**
 426  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
 427  * @rx_ring: Rx ring
 428  * @budget: NAPI budget
 429  *
 430  * Returns amount of work completed
 431  **/
 432 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
 433 {
 434         unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 435         u16 next_to_process = rx_ring->next_to_process;
 436         u16 next_to_clean = rx_ring->next_to_clean;
 437         unsigned int xdp_res, xdp_xmit = 0;
 438         struct xdp_buff *first = NULL;
 439         u32 count = rx_ring->count;
 440         struct bpf_prog *xdp_prog;
 441         u32 entries_to_alloc;
 442         bool failure = false;
 443
 444         if (next_to_process != next_to_clean)
 445                 first = *i40e_rx_bi(rx_ring, next_to_clean);
 446
 447         /* NB! xdp_prog will always be !NULL, due to the fact that
 448          * this path is enabled by setting an XDP program.
 449          */
 450         xdp_prog = READ_ONCE(rx_ring->xdp_prog);
 451
 452         while (likely(total_rx_packets < (unsigned int)budget)) {
 453                 union i40e_rx_desc *rx_desc;
 454                 unsigned int rx_packets;
 455                 unsigned int rx_bytes;
 456                 struct xdp_buff *bi;
 457                 unsigned int size;
 458                 u64 qword;
 459
 460                 rx_desc = I40E_RX_DESC(rx_ring, next_to_process);
 461                 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
 462
 463                 /* This memory barrier is needed to keep us from reading
 464                  * any other fields out of the rx_desc until we have
 465                  * verified the descriptor has been written back.
 466                  */
 467                 dma_rmb();
 468
 469                 if (i40e_rx_is_programming_status(qword)) {
 470                         i40e_clean_programming_status(rx_ring,
 471                                                       rx_desc->raw.qword[0],
 472                                                       qword);
 473                         bi = *i40e_rx_bi(rx_ring, next_to_process);
 474                         xsk_buff_free(bi);
 475                         if (++next_to_process == count)
 476                                 next_to_process = 0;
 477                         continue;
 478                 }
 479
 480                 size = FIELD_GET(I40E_RXD_QW1_LENGTH_PBUF_MASK, qword);
 481                 if (!size)
 482                         break;
 483
 484                 bi = *i40e_rx_bi(rx_ring, next_to_process);
 485                 xsk_buff_set_size(bi, size);
 486                 xsk_buff_dma_sync_for_cpu(bi, rx_ring->xsk_pool);
 487
 488                 if (!first)
 489                         first = bi;
 490                 else if (i40e_add_xsk_frag(rx_ring, first, bi, size))
 491                         break;
 492
 493                 if (++next_to_process == count)
 494                         next_to_process = 0;
 495
 496                 if (i40e_is_non_eop(rx_ring, rx_desc))
 497                         continue;
 498
 499                 xdp_res = i40e_run_xdp_zc(rx_ring, first, xdp_prog);
 500                 i40e_handle_xdp_result_zc(rx_ring, first, rx_desc, &rx_packets,
 501                                           &rx_bytes, xdp_res, &failure);
 502                 next_to_clean = next_to_process;
 503                 if (failure)
 504                         break;
 505                 total_rx_packets += rx_packets;
 506                 total_rx_bytes += rx_bytes;
 507                 xdp_xmit |= xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR);
 508                 first = NULL;
 509         }
 510
 511         rx_ring->next_to_clean = next_to_clean;
 512         rx_ring->next_to_process = next_to_process;
 513
 514         entries_to_alloc = I40E_DESC_UNUSED(rx_ring);
 515         if (entries_to_alloc >= I40E_RX_BUFFER_WRITE)
 516                 failure |= !i40e_alloc_rx_buffers_zc(rx_ring, entries_to_alloc);
 517
 518         i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
 519         i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
 520
 521         if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) {
 522                 if (failure || next_to_clean == rx_ring->next_to_use)
 523                         xsk_set_rx_need_wakeup(rx_ring->xsk_pool);
 524                 else
 525                         xsk_clear_rx_need_wakeup(rx_ring->xsk_pool);
 526
 527                 return (int)total_rx_packets;
 528         }
 529         return failure ? budget : (int)total_rx_packets;
 530 }
 531
 532 static void i40e_xmit_pkt(struct i40e_ring *xdp_ring, struct xdp_desc *desc,
 533                           unsigned int *total_bytes)
 534 {
 535         u32 cmd = I40E_TX_DESC_CMD_ICRC | xsk_is_eop_desc(desc);
 536         struct i40e_tx_desc *tx_desc;
 537         dma_addr_t dma;
 538
 539         dma = xsk_buff_raw_get_dma(xdp_ring->xsk_pool, desc->addr);
 540         xsk_buff_raw_dma_sync_for_device(xdp_ring->xsk_pool, dma, desc->len);
 541
 542         tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use++);
 543         tx_desc->buffer_addr = cpu_to_le64(dma);
 544         tx_desc->cmd_type_offset_bsz = build_ctob(cmd, 0, desc->len, 0);
 545
 546         *total_bytes += desc->len;
 547 }
 548
 549 static void i40e_xmit_pkt_batch(struct i40e_ring *xdp_ring, struct xdp_desc *desc,
 550                                 unsigned int *total_bytes)
 551 {
 552         u16 ntu = xdp_ring->next_to_use;
 553         struct i40e_tx_desc *tx_desc;
 554         dma_addr_t dma;
 555         u32 i;
 556
 557         loop_unrolled_for(i = 0; i < PKTS_PER_BATCH; i++) {
 558                 u32 cmd = I40E_TX_DESC_CMD_ICRC | xsk_is_eop_desc(&desc[i]);
 559
 560                 dma = xsk_buff_raw_get_dma(xdp_ring->xsk_pool, desc[i].addr);
 561                 xsk_buff_raw_dma_sync_for_device(xdp_ring->xsk_pool, dma, desc[i].len);
 562
 563                 tx_desc = I40E_TX_DESC(xdp_ring, ntu++);
 564                 tx_desc->buffer_addr = cpu_to_le64(dma);
 565                 tx_desc->cmd_type_offset_bsz = build_ctob(cmd, 0, desc[i].len, 0);
 566
 567                 *total_bytes += desc[i].len;
 568         }
 569
 570         xdp_ring->next_to_use = ntu;
 571 }
 572
 573 static void i40e_fill_tx_hw_ring(struct i40e_ring *xdp_ring, struct xdp_desc *descs, u32 nb_pkts,
 574                                  unsigned int *total_bytes)
 575 {
 576         u32 batched, leftover, i;
 577
 578         batched = nb_pkts & ~(PKTS_PER_BATCH - 1);
 579         leftover = nb_pkts & (PKTS_PER_BATCH - 1);
 580         for (i = 0; i < batched; i += PKTS_PER_BATCH)
 581                 i40e_xmit_pkt_batch(xdp_ring, &descs[i], total_bytes);
 582         for (i = batched; i < batched + leftover; i++)
 583                 i40e_xmit_pkt(xdp_ring, &descs[i], total_bytes);
 584 }
 585
 586 static void i40e_set_rs_bit(struct i40e_ring *xdp_ring)
 587 {
 588         u16 ntu = xdp_ring->next_to_use ? xdp_ring->next_to_use - 1 : xdp_ring->count - 1;
 589         struct i40e_tx_desc *tx_desc;
 590
 591         tx_desc = I40E_TX_DESC(xdp_ring, ntu);
 592         tx_desc->cmd_type_offset_bsz |= cpu_to_le64(I40E_TX_DESC_CMD_RS << I40E_TXD_QW1_CMD_SHIFT);
 593 }
 594
 595 /**
 596  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
 597  * @xdp_ring: XDP Tx ring
 598  * @budget: NAPI budget
 599  *
 600  * Returns true if the work is finished.
 601  **/
 602 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 603 {
 604         struct xdp_desc *descs = xdp_ring->xsk_pool->tx_descs;
 605         u32 nb_pkts, nb_processed = 0;
 606         unsigned int total_bytes = 0;
 607
 608         nb_pkts = xsk_tx_peek_release_desc_batch(xdp_ring->xsk_pool, budget);
 609         if (!nb_pkts)
 610                 return true;
 611
 612         if (xdp_ring->next_to_use + nb_pkts >= xdp_ring->count) {
 613                 nb_processed = xdp_ring->count - xdp_ring->next_to_use;
 614                 i40e_fill_tx_hw_ring(xdp_ring, descs, nb_processed, &total_bytes);
 615                 xdp_ring->next_to_use = 0;
 616         }
 617
 618         i40e_fill_tx_hw_ring(xdp_ring, &descs[nb_processed], nb_pkts - nb_processed,
 619                              &total_bytes);
 620
 621         /* Request an interrupt for the last frame and bump tail ptr. */
 622         i40e_set_rs_bit(xdp_ring);
 623         i40e_xdp_ring_update_tail(xdp_ring);
 624
 625         i40e_update_tx_stats(xdp_ring, nb_pkts, total_bytes);
 626
 627         return nb_pkts < budget;
 628 }
 629
 630 /**
 631  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
 632  * @tx_ring: XDP Tx ring
 633  * @tx_bi: Tx buffer info to clean
 634  **/
 635 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
 636                                      struct i40e_tx_buffer *tx_bi)
 637 {
 638         xdp_return_frame(tx_bi->xdpf);
 639         tx_ring->xdp_tx_active--;
 640         dma_unmap_single(tx_ring->dev,
 641                          dma_unmap_addr(tx_bi, dma),
 642                          dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
 643         dma_unmap_len_set(tx_bi, len, 0);
 644 }
 645
 646 /**
 647  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
 648  * @vsi: Current VSI
 649  * @tx_ring: XDP Tx ring
 650  *
 651  * Returns true if cleanup/transmission is done.
 652  **/
 653 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi, struct i40e_ring *tx_ring)
 654 {
 655         struct xsk_buff_pool *bp = tx_ring->xsk_pool;
 656         u32 i, completed_frames, xsk_frames = 0;
 657         u32 head_idx = i40e_get_head(tx_ring);
 658         struct i40e_tx_buffer *tx_bi;
 659         unsigned int ntc;
 660
 661         if (head_idx < tx_ring->next_to_clean)
 662                 head_idx += tx_ring->count;
 663         completed_frames = head_idx - tx_ring->next_to_clean;
 664
 665         if (completed_frames == 0)
 666                 goto out_xmit;
 667
 668         if (likely(!tx_ring->xdp_tx_active)) {
 669                 xsk_frames = completed_frames;
 670                 goto skip;
 671         }
 672
 673         ntc = tx_ring->next_to_clean;
 674
 675         for (i = 0; i < completed_frames; i++) {
 676                 tx_bi = &tx_ring->tx_bi[ntc];
 677
 678                 if (tx_bi->xdpf) {
 679                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 680                         tx_bi->xdpf = NULL;
 681                 } else {
 682                         xsk_frames++;
 683                 }
 684
 685                 if (++ntc >= tx_ring->count)
 686                         ntc = 0;
 687         }
 688
 689 skip:
 690         tx_ring->next_to_clean += completed_frames;
 691         if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
 692                 tx_ring->next_to_clean -= tx_ring->count;
 693
 694         if (xsk_frames)
 695                 xsk_tx_completed(bp, xsk_frames);
 696
 697         i40e_arm_wb(tx_ring, vsi, completed_frames);
 698
 699 out_xmit:
 700         if (xsk_uses_need_wakeup(tx_ring->xsk_pool))
 701                 xsk_set_tx_need_wakeup(tx_ring->xsk_pool);
 702
 703         return i40e_xmit_zc(tx_ring, I40E_DESC_UNUSED(tx_ring));
 704 }
 705
 706 /**
 707  * i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
 708  * @dev: the netdevice
 709  * @queue_id: queue id to wake up
 710  * @flags: ignored in our case since we have Rx and Tx in the same NAPI.
 711  *
 712  * Returns <0 for errors, 0 otherwise.
 713  **/
 714 int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
 715 {
 716         struct i40e_netdev_priv *np = netdev_priv(dev);
 717         struct i40e_vsi *vsi = np->vsi;
 718         struct i40e_pf *pf = vsi->back;
 719         struct i40e_ring *ring;
 720
 721         if (test_bit(__I40E_CONFIG_BUSY, pf->state))
 722                 return -EAGAIN;
 723
 724         if (test_bit(__I40E_VSI_DOWN, vsi->state))
 725                 return -ENETDOWN;
 726
 727         if (!i40e_enabled_xdp_vsi(vsi))
 728                 return -EINVAL;
 729
 730         if (queue_id >= vsi->num_queue_pairs)
 731                 return -EINVAL;
 732
 733         if (!vsi->xdp_rings[queue_id]->xsk_pool)
 734                 return -EINVAL;
 735
 736         ring = vsi->xdp_rings[queue_id];
 737
 738         /* The idea here is that if NAPI is running, mark a miss, so
 739          * it will run again. If not, trigger an interrupt and
 740          * schedule the NAPI from interrupt context. If NAPI would be
 741          * scheduled here, the interrupt affinity would not be
 742          * honored.
 743          */
 744         if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
 745                 i40e_force_wb(vsi, ring->q_vector);
 746
 747         return 0;
 748 }
 749
 750 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
 751 {
 752         u16 ntc = rx_ring->next_to_clean;
 753         u16 ntu = rx_ring->next_to_use;
 754
 755         while (ntc != ntu) {
 756                 struct xdp_buff *rx_bi = *i40e_rx_bi(rx_ring, ntc);
 757
 758                 xsk_buff_free(rx_bi);
 759                 ntc++;
 760                 if (ntc >= rx_ring->count)
 761                         ntc = 0;
 762         }
 763 }
 764
 765 /**
 766  * i40e_xsk_clean_tx_ring - Clean the XDP Tx ring on shutdown
 767  * @tx_ring: XDP Tx ring
 768  **/
 769 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
 770 {
 771         u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
 772         struct xsk_buff_pool *bp = tx_ring->xsk_pool;
 773         struct i40e_tx_buffer *tx_bi;
 774         u32 xsk_frames = 0;
 775
 776         while (ntc != ntu) {
 777                 tx_bi = &tx_ring->tx_bi[ntc];
 778
 779                 if (tx_bi->xdpf)
 780                         i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
 781                 else
 782                         xsk_frames++;
 783
 784                 tx_bi->xdpf = NULL;
 785
 786                 ntc++;
 787                 if (ntc >= tx_ring->count)
 788                         ntc = 0;
 789         }
 790
 791         if (xsk_frames)
 792                 xsk_tx_completed(bp, xsk_frames);
 793 }
 794
 795 /**
 796  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have an AF_XDP
 797  * buffer pool attached
 798  * @vsi: vsi
 799  *
 800  * Returns true if any of the Rx rings has an AF_XDP buffer pool attached
 801  **/
 802 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
 803 {
 804         struct net_device *netdev = vsi->netdev;
 805         int i;
 806
 807         for (i = 0; i < vsi->num_queue_pairs; i++) {
 808                 if (xsk_get_pool_from_qid(netdev, i))
 809                         return true;
 810         }
 811
 812         return false;
 813 }