drivers/net/ethernet/aquantia/atlantic/aq_ring.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * aQuantia Corporation Network Driver
   4  * Copyright (C) 2014-2019 aQuantia Corporation. All rights reserved
   5  */
   6
   7 /* File aq_ring.c: Definition of functions for Rx/Tx rings. */
   8
   9 #include "aq_ring.h"
  10 #include "aq_nic.h"
  11 #include "aq_hw.h"
  12 #include "aq_hw_utils.h"
  13 #include "aq_ptp.h"
  14
  15 #include <linux/netdevice.h>
  16 #include <linux/etherdevice.h>
  17
  18 static inline void aq_free_rxpage(struct aq_rxpage *rxpage, struct device *dev)
  19 {
  20         unsigned int len = PAGE_SIZE << rxpage->order;
  21
  22         dma_unmap_page(dev, rxpage->daddr, len, DMA_FROM_DEVICE);
  23
  24         /* Drop the ref for being in the ring. */
  25         __free_pages(rxpage->page, rxpage->order);
  26         rxpage->page = NULL;
  27 }
  28
  29 static int aq_get_rxpage(struct aq_rxpage *rxpage, unsigned int order,
  30                          struct device *dev)
  31 {
  32         struct page *page;
  33         int ret = -ENOMEM;
  34         dma_addr_t daddr;
  35
  36         page = dev_alloc_pages(order);
  37         if (unlikely(!page))
  38                 goto err_exit;
  39
  40         daddr = dma_map_page(dev, page, 0, PAGE_SIZE << order,
  41                              DMA_FROM_DEVICE);
  42
  43         if (unlikely(dma_mapping_error(dev, daddr)))
  44                 goto free_page;
  45
  46         rxpage->page = page;
  47         rxpage->daddr = daddr;
  48         rxpage->order = order;
  49         rxpage->pg_off = 0;
  50
  51         return 0;
  52
  53 free_page:
  54         __free_pages(page, order);
  55
  56 err_exit:
  57         return ret;
  58 }
  59
  60 static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf,
  61                           int order)
  62 {
  63         int ret;
  64
  65         if (rxbuf->rxdata.page) {
  66                 /* One means ring is the only user and can reuse */
  67                 if (page_ref_count(rxbuf->rxdata.page) > 1) {
  68                         /* Try reuse buffer */
  69                         rxbuf->rxdata.pg_off += AQ_CFG_RX_FRAME_MAX;
  70                         if (rxbuf->rxdata.pg_off + AQ_CFG_RX_FRAME_MAX <=
  71                                 (PAGE_SIZE << order)) {
  72                                 self->stats.rx.pg_flips++;
  73                         } else {
  74                                 /* Buffer exhausted. We have other users and
  75                                  * should release this page and realloc
  76                                  */
  77                                 aq_free_rxpage(&rxbuf->rxdata,
  78                                                aq_nic_get_dev(self->aq_nic));
  79                                 self->stats.rx.pg_losts++;
  80                         }
  81                 } else {
  82                         rxbuf->rxdata.pg_off = 0;
  83                         self->stats.rx.pg_reuses++;
  84                 }
  85         }
  86
  87         if (!rxbuf->rxdata.page) {
  88                 ret = aq_get_rxpage(&rxbuf->rxdata, order,
  89                                     aq_nic_get_dev(self->aq_nic));
  90                 return ret;
  91         }
  92
  93         return 0;
  94 }
  95
  96 static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
  97                                        struct aq_nic_s *aq_nic)
  98 {
  99         int err = 0;
 100
 101         self->buff_ring =
 102                 kcalloc(self->size, sizeof(struct aq_ring_buff_s), GFP_KERNEL);
 103
 104         if (!self->buff_ring) {
 105                 err = -ENOMEM;
 106                 goto err_exit;
 107         }
 108         self->dx_ring = dma_alloc_coherent(aq_nic_get_dev(aq_nic),
 109                                            self->size * self->dx_size,
 110                                            &self->dx_ring_pa, GFP_KERNEL);
 111         if (!self->dx_ring) {
 112                 err = -ENOMEM;
 113                 goto err_exit;
 114         }
 115
 116 err_exit:
 117         if (err < 0) {
 118                 aq_ring_free(self);
 119                 self = NULL;
 120         }
 121
 122         return self;
 123 }
 124
 125 struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
 126                                    struct aq_nic_s *aq_nic,
 127                                    unsigned int idx,
 128                                    struct aq_nic_cfg_s *aq_nic_cfg)
 129 {
 130         int err = 0;
 131
 132         self->aq_nic = aq_nic;
 133         self->idx = idx;
 134         self->size = aq_nic_cfg->txds;
 135         self->dx_size = aq_nic_cfg->aq_hw_caps->txd_size;
 136
 137         self = aq_ring_alloc(self, aq_nic);
 138         if (!self) {
 139                 err = -ENOMEM;
 140                 goto err_exit;
 141         }
 142
 143 err_exit:
 144         if (err < 0) {
 145                 aq_ring_free(self);
 146                 self = NULL;
 147         }
 148
 149         return self;
 150 }
 151
 152 struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
 153                                    struct aq_nic_s *aq_nic,
 154                                    unsigned int idx,
 155                                    struct aq_nic_cfg_s *aq_nic_cfg)
 156 {
 157         int err = 0;
 158
 159         self->aq_nic = aq_nic;
 160         self->idx = idx;
 161         self->size = aq_nic_cfg->rxds;
 162         self->dx_size = aq_nic_cfg->aq_hw_caps->rxd_size;
 163         self->page_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE +
 164                                (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1;
 165
 166         if (aq_nic_cfg->rxpageorder > self->page_order)
 167                 self->page_order = aq_nic_cfg->rxpageorder;
 168
 169         self = aq_ring_alloc(self, aq_nic);
 170         if (!self) {
 171                 err = -ENOMEM;
 172                 goto err_exit;
 173         }
 174
 175 err_exit:
 176         if (err < 0) {
 177                 aq_ring_free(self);
 178                 self = NULL;
 179         }
 180
 181         return self;
 182 }
 183
 184 struct aq_ring_s *
 185 aq_ring_hwts_rx_alloc(struct aq_ring_s *self, struct aq_nic_s *aq_nic,
 186                       unsigned int idx, unsigned int size, unsigned int dx_size)
 187 {
 188         struct device *dev = aq_nic_get_dev(aq_nic);
 189         size_t sz = size * dx_size + AQ_CFG_RXDS_DEF;
 190
 191         memset(self, 0, sizeof(*self));
 192
 193         self->aq_nic = aq_nic;
 194         self->idx = idx;
 195         self->size = size;
 196         self->dx_size = dx_size;
 197
 198         self->dx_ring = dma_alloc_coherent(dev, sz, &self->dx_ring_pa,
 199                                            GFP_KERNEL);
 200         if (!self->dx_ring) {
 201                 aq_ring_free(self);
 202                 return NULL;
 203         }
 204
 205         return self;
 206 }
 207
 208 int aq_ring_init(struct aq_ring_s *self)
 209 {
 210         self->hw_head = 0;
 211         self->sw_head = 0;
 212         self->sw_tail = 0;
 213
 214         return 0;
 215 }
 216
 217 static inline bool aq_ring_dx_in_range(unsigned int h, unsigned int i,
 218                                        unsigned int t)
 219 {
 220         return (h < t) ? ((h < i) && (i < t)) : ((h < i) || (i < t));
 221 }
 222
 223 void aq_ring_update_queue_state(struct aq_ring_s *ring)
 224 {
 225         if (aq_ring_avail_dx(ring) <= AQ_CFG_SKB_FRAGS_MAX)
 226                 aq_ring_queue_stop(ring);
 227         else if (aq_ring_avail_dx(ring) > AQ_CFG_RESTART_DESC_THRES)
 228                 aq_ring_queue_wake(ring);
 229 }
 230
 231 void aq_ring_queue_wake(struct aq_ring_s *ring)
 232 {
 233         struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
 234
 235         if (__netif_subqueue_stopped(ndev, ring->idx)) {
 236                 netif_wake_subqueue(ndev, ring->idx);
 237                 ring->stats.tx.queue_restarts++;
 238         }
 239 }
 240
 241 void aq_ring_queue_stop(struct aq_ring_s *ring)
 242 {
 243         struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
 244
 245         if (!__netif_subqueue_stopped(ndev, ring->idx))
 246                 netif_stop_subqueue(ndev, ring->idx);
 247 }
 248
 249 bool aq_ring_tx_clean(struct aq_ring_s *self)
 250 {
 251         struct device *dev = aq_nic_get_dev(self->aq_nic);
 252         unsigned int budget;
 253
 254         for (budget = AQ_CFG_TX_CLEAN_BUDGET;
 255              budget && self->sw_head != self->hw_head; budget--) {
 256                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 257
 258                 if (likely(buff->is_mapped)) {
 259                         if (unlikely(buff->is_sop)) {
 260                                 if (!buff->is_eop &&
 261                                     buff->eop_index != 0xffffU &&
 262                                     (!aq_ring_dx_in_range(self->sw_head,
 263                                                 buff->eop_index,
 264                                                 self->hw_head)))
 265                                         break;
 266
 267                                 dma_unmap_single(dev, buff->pa, buff->len,
 268                                                  DMA_TO_DEVICE);
 269                         } else {
 270                                 dma_unmap_page(dev, buff->pa, buff->len,
 271                                                DMA_TO_DEVICE);
 272                         }
 273                 }
 274
 275                 if (unlikely(buff->is_eop))
 276                         dev_kfree_skb_any(buff->skb);
 277
 278                 buff->pa = 0U;
 279                 buff->eop_index = 0xffffU;
 280                 self->sw_head = aq_ring_next_dx(self, self->sw_head);
 281         }
 282
 283         return !!budget;
 284 }
 285
 286 static void aq_rx_checksum(struct aq_ring_s *self,
 287                            struct aq_ring_buff_s *buff,
 288                            struct sk_buff *skb)
 289 {
 290         if (!(self->aq_nic->ndev->features & NETIF_F_RXCSUM))
 291                 return;
 292
 293         if (unlikely(buff->is_cso_err)) {
 294                 ++self->stats.rx.errors;
 295                 skb->ip_summed = CHECKSUM_NONE;
 296                 return;
 297         }
 298         if (buff->is_ip_cso) {
 299                 __skb_incr_checksum_unnecessary(skb);
 300         } else {
 301                 skb->ip_summed = CHECKSUM_NONE;
 302         }
 303
 304         if (buff->is_udp_cso || buff->is_tcp_cso)
 305                 __skb_incr_checksum_unnecessary(skb);
 306 }
 307
 308 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
 309 int aq_ring_rx_clean(struct aq_ring_s *self,
 310                      struct napi_struct *napi,
 311                      int *work_done,
 312                      int budget)
 313 {
 314         struct net_device *ndev = aq_nic_get_ndev(self->aq_nic);
 315         bool is_rsc_completed = true;
 316         int err = 0;
 317
 318         for (; (self->sw_head != self->hw_head) && budget;
 319                 self->sw_head = aq_ring_next_dx(self, self->sw_head),
 320                 --budget, ++(*work_done)) {
 321                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 322                 bool is_ptp_ring = aq_ptp_ring(self->aq_nic, self);
 323                 struct aq_ring_buff_s *buff_ = NULL;
 324                 struct sk_buff *skb = NULL;
 325                 unsigned int next_ = 0U;
 326                 unsigned int i = 0U;
 327                 u16 hdr_len;
 328
 329                 if (buff->is_cleaned)
 330                         continue;
 331
 332                 if (!buff->is_eop) {
 333                         buff_ = buff;
 334                         do {
 335                                 next_ = buff_->next,
 336                                 buff_ = &self->buff_ring[next_];
 337                                 is_rsc_completed =
 338                                         aq_ring_dx_in_range(self->sw_head,
 339                                                             next_,
 340                                                             self->hw_head);
 341
 342                                 if (unlikely(!is_rsc_completed))
 343                                         break;
 344
 345                                 buff->is_error |= buff_->is_error;
 346                                 buff->is_cso_err |= buff_->is_cso_err;
 347
 348                         } while (!buff_->is_eop);
 349
 350                         if (!is_rsc_completed) {
 351                                 err = 0;
 352                                 goto err_exit;
 353                         }
 354                         if (buff->is_error || buff->is_cso_err) {
 355                                 buff_ = buff;
 356                                 do {
 357                                         next_ = buff_->next,
 358                                         buff_ = &self->buff_ring[next_];
 359
 360                                         buff_->is_cleaned = true;
 361                                 } while (!buff_->is_eop);
 362
 363                                 ++self->stats.rx.errors;
 364                                 continue;
 365                         }
 366                 }
 367
 368                 if (buff->is_error) {
 369                         ++self->stats.rx.errors;
 370                         continue;
 371                 }
 372
 373                 dma_sync_single_range_for_cpu(aq_nic_get_dev(self->aq_nic),
 374                                               buff->rxdata.daddr,
 375                                               buff->rxdata.pg_off,
 376                                               buff->len, DMA_FROM_DEVICE);
 377
 378                 /* for single fragment packets use build_skb() */
 379                 if (buff->is_eop &&
 380                     buff->len <= AQ_CFG_RX_FRAME_MAX - AQ_SKB_ALIGN) {
 381                         skb = build_skb(aq_buf_vaddr(&buff->rxdata),
 382                                         AQ_CFG_RX_FRAME_MAX);
 383                         if (unlikely(!skb)) {
 384                                 err = -ENOMEM;
 385                                 goto err_exit;
 386                         }
 387                         if (is_ptp_ring)
 388                                 buff->len -=
 389                                         aq_ptp_extract_ts(self->aq_nic, skb,
 390                                                 aq_buf_vaddr(&buff->rxdata),
 391                                                 buff->len);
 392                         skb_put(skb, buff->len);
 393                         page_ref_inc(buff->rxdata.page);
 394                 } else {
 395                         skb = napi_alloc_skb(napi, AQ_CFG_RX_HDR_SIZE);
 396                         if (unlikely(!skb)) {
 397                                 err = -ENOMEM;
 398                                 goto err_exit;
 399                         }
 400                         if (is_ptp_ring)
 401                                 buff->len -=
 402                                         aq_ptp_extract_ts(self->aq_nic, skb,
 403                                                 aq_buf_vaddr(&buff->rxdata),
 404                                                 buff->len);
 405
 406                         hdr_len = buff->len;
 407                         if (hdr_len > AQ_CFG_RX_HDR_SIZE)
 408                                 hdr_len = eth_get_headlen(skb->dev,
 409                                                           aq_buf_vaddr(&buff->rxdata),
 410                                                           AQ_CFG_RX_HDR_SIZE);
 411
 412                         memcpy(__skb_put(skb, hdr_len), aq_buf_vaddr(&buff->rxdata),
 413                                ALIGN(hdr_len, sizeof(long)));
 414
 415                         if (buff->len - hdr_len > 0) {
 416                                 skb_add_rx_frag(skb, 0, buff->rxdata.page,
 417                                                 buff->rxdata.pg_off + hdr_len,
 418                                                 buff->len - hdr_len,
 419                                                 AQ_CFG_RX_FRAME_MAX);
 420                                 page_ref_inc(buff->rxdata.page);
 421                         }
 422
 423                         if (!buff->is_eop) {
 424                                 buff_ = buff;
 425                                 i = 1U;
 426                                 do {
 427                                         next_ = buff_->next,
 428                                         buff_ = &self->buff_ring[next_];
 429
 430                                         dma_sync_single_range_for_cpu(
 431                                                         aq_nic_get_dev(self->aq_nic),
 432                                                         buff_->rxdata.daddr,
 433                                                         buff_->rxdata.pg_off,
 434                                                         buff_->len,
 435                                                         DMA_FROM_DEVICE);
 436                                         skb_add_rx_frag(skb, i++,
 437                                                         buff_->rxdata.page,
 438                                                         buff_->rxdata.pg_off,
 439                                                         buff_->len,
 440                                                         AQ_CFG_RX_FRAME_MAX);
 441                                         page_ref_inc(buff_->rxdata.page);
 442                                         buff_->is_cleaned = 1;
 443
 444                                         buff->is_ip_cso &= buff_->is_ip_cso;
 445                                         buff->is_udp_cso &= buff_->is_udp_cso;
 446                                         buff->is_tcp_cso &= buff_->is_tcp_cso;
 447                                         buff->is_cso_err |= buff_->is_cso_err;
 448
 449                                 } while (!buff_->is_eop);
 450                         }
 451                 }
 452
 453                 if (buff->is_vlan)
 454                         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 455                                                buff->vlan_rx_tag);
 456
 457                 skb->protocol = eth_type_trans(skb, ndev);
 458
 459                 aq_rx_checksum(self, buff, skb);
 460
 461                 skb_set_hash(skb, buff->rss_hash,
 462                              buff->is_hash_l4 ? PKT_HASH_TYPE_L4 :
 463                              PKT_HASH_TYPE_NONE);
 464                 /* Send all PTP traffic to 0 queue */
 465                 skb_record_rx_queue(skb, is_ptp_ring ? 0 : self->idx);
 466
 467                 ++self->stats.rx.packets;
 468                 self->stats.rx.bytes += skb->len;
 469
 470                 napi_gro_receive(napi, skb);
 471         }
 472
 473 err_exit:
 474         return err;
 475 }
 476
 477 void aq_ring_hwts_rx_clean(struct aq_ring_s *self, struct aq_nic_s *aq_nic)
 478 {
 479         while (self->sw_head != self->hw_head) {
 480                 u64 ns;
 481
 482                 aq_nic->aq_hw_ops->extract_hwts(aq_nic->aq_hw,
 483                                                 self->dx_ring +
 484                                                 (self->sw_head * self->dx_size),
 485                                                 self->dx_size, &ns);
 486                 aq_ptp_tx_hwtstamp(aq_nic, ns);
 487
 488                 self->sw_head = aq_ring_next_dx(self, self->sw_head);
 489         }
 490 }
 491
 492 int aq_ring_rx_fill(struct aq_ring_s *self)
 493 {
 494         unsigned int page_order = self->page_order;
 495         struct aq_ring_buff_s *buff = NULL;
 496         int err = 0;
 497         int i = 0;
 498
 499         if (aq_ring_avail_dx(self) < min_t(unsigned int, AQ_CFG_RX_REFILL_THRES,
 500                                            self->size / 2))
 501                 return err;
 502
 503         for (i = aq_ring_avail_dx(self); i--;
 504                 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) {
 505                 buff = &self->buff_ring[self->sw_tail];
 506
 507                 buff->flags = 0U;
 508                 buff->len = AQ_CFG_RX_FRAME_MAX;
 509
 510                 err = aq_get_rxpages(self, buff, page_order);
 511                 if (err)
 512                         goto err_exit;
 513
 514                 buff->pa = aq_buf_daddr(&buff->rxdata);
 515                 buff = NULL;
 516         }
 517
 518 err_exit:
 519         return err;
 520 }
 521
 522 void aq_ring_rx_deinit(struct aq_ring_s *self)
 523 {
 524         if (!self)
 525                 goto err_exit;
 526
 527         for (; self->sw_head != self->sw_tail;
 528                 self->sw_head = aq_ring_next_dx(self, self->sw_head)) {
 529                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 530
 531                 aq_free_rxpage(&buff->rxdata, aq_nic_get_dev(self->aq_nic));
 532         }
 533
 534 err_exit:;
 535 }
 536
 537 void aq_ring_free(struct aq_ring_s *self)
 538 {
 539         if (!self)
 540                 goto err_exit;
 541
 542         kfree(self->buff_ring);
 543
 544         if (self->dx_ring)
 545                 dma_free_coherent(aq_nic_get_dev(self->aq_nic),
 546                                   self->size * self->dx_size, self->dx_ring,
 547                                   self->dx_ring_pa);
 548
 549 err_exit:;
 550 }