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

   1 /*
   2  * aQuantia Corporation Network Driver
   3  * Copyright (C) 2014-2017 aQuantia Corporation. All rights reserved
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  */
   9
  10 /* File aq_ring.c: Definition of functions for Rx/Tx rings. */
  11
  12 #include "aq_ring.h"
  13 #include "aq_nic.h"
  14 #include "aq_hw.h"
  15
  16 #include <linux/netdevice.h>
  17 #include <linux/etherdevice.h>
  18
  19 static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
  20                                        struct aq_nic_s *aq_nic)
  21 {
  22         int err = 0;
  23
  24         self->buff_ring =
  25                 kcalloc(self->size, sizeof(struct aq_ring_buff_s), GFP_KERNEL);
  26
  27         if (!self->buff_ring) {
  28                 err = -ENOMEM;
  29                 goto err_exit;
  30         }
  31         self->dx_ring = dma_alloc_coherent(aq_nic_get_dev(aq_nic),
  32                                            self->size * self->dx_size,
  33                                            &self->dx_ring_pa, GFP_KERNEL);
  34         if (!self->dx_ring) {
  35                 err = -ENOMEM;
  36                 goto err_exit;
  37         }
  38
  39 err_exit:
  40         if (err < 0) {
  41                 aq_ring_free(self);
  42                 self = NULL;
  43         }
  44         return self;
  45 }
  46
  47 struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
  48                                    struct aq_nic_s *aq_nic,
  49                                    unsigned int idx,
  50                                    struct aq_nic_cfg_s *aq_nic_cfg)
  51 {
  52         int err = 0;
  53
  54         self->aq_nic = aq_nic;
  55         self->idx = idx;
  56         self->size = aq_nic_cfg->txds;
  57         self->dx_size = aq_nic_cfg->aq_hw_caps->txd_size;
  58
  59         self = aq_ring_alloc(self, aq_nic);
  60         if (!self) {
  61                 err = -ENOMEM;
  62                 goto err_exit;
  63         }
  64
  65 err_exit:
  66         if (err < 0) {
  67                 aq_ring_free(self);
  68                 self = NULL;
  69         }
  70         return self;
  71 }
  72
  73 struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
  74                                    struct aq_nic_s *aq_nic,
  75                                    unsigned int idx,
  76                                    struct aq_nic_cfg_s *aq_nic_cfg)
  77 {
  78         int err = 0;
  79
  80         self->aq_nic = aq_nic;
  81         self->idx = idx;
  82         self->size = aq_nic_cfg->rxds;
  83         self->dx_size = aq_nic_cfg->aq_hw_caps->rxd_size;
  84
  85         self = aq_ring_alloc(self, aq_nic);
  86         if (!self) {
  87                 err = -ENOMEM;
  88                 goto err_exit;
  89         }
  90
  91 err_exit:
  92         if (err < 0) {
  93                 aq_ring_free(self);
  94                 self = NULL;
  95         }
  96         return self;
  97 }
  98
  99 int aq_ring_init(struct aq_ring_s *self)
 100 {
 101         self->hw_head = 0;
 102         self->sw_head = 0;
 103         self->sw_tail = 0;
 104         return 0;
 105 }
 106
 107 static inline bool aq_ring_dx_in_range(unsigned int h, unsigned int i,
 108                                        unsigned int t)
 109 {
 110         return (h < t) ? ((h < i) && (i < t)) : ((h < i) || (i < t));
 111 }
 112
 113 void aq_ring_update_queue_state(struct aq_ring_s *ring)
 114 {
 115         if (aq_ring_avail_dx(ring) <= AQ_CFG_SKB_FRAGS_MAX)
 116                 aq_ring_queue_stop(ring);
 117         else if (aq_ring_avail_dx(ring) > AQ_CFG_RESTART_DESC_THRES)
 118                 aq_ring_queue_wake(ring);
 119 }
 120
 121 void aq_ring_queue_wake(struct aq_ring_s *ring)
 122 {
 123         struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
 124
 125         if (__netif_subqueue_stopped(ndev, ring->idx)) {
 126                 netif_wake_subqueue(ndev, ring->idx);
 127                 ring->stats.tx.queue_restarts++;
 128         }
 129 }
 130
 131 void aq_ring_queue_stop(struct aq_ring_s *ring)
 132 {
 133         struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
 134
 135         if (!__netif_subqueue_stopped(ndev, ring->idx))
 136                 netif_stop_subqueue(ndev, ring->idx);
 137 }
 138
 139 bool aq_ring_tx_clean(struct aq_ring_s *self)
 140 {
 141         struct device *dev = aq_nic_get_dev(self->aq_nic);
 142         unsigned int budget = AQ_CFG_TX_CLEAN_BUDGET;
 143
 144         for (; self->sw_head != self->hw_head && budget--;
 145                 self->sw_head = aq_ring_next_dx(self, self->sw_head)) {
 146                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 147
 148                 if (likely(buff->is_mapped)) {
 149                         if (unlikely(buff->is_sop)) {
 150                                 if (!buff->is_eop &&
 151                                     buff->eop_index != 0xffffU &&
 152                                     (!aq_ring_dx_in_range(self->sw_head,
 153                                                 buff->eop_index,
 154                                                 self->hw_head)))
 155                                         break;
 156
 157                                 dma_unmap_single(dev, buff->pa, buff->len,
 158                                                  DMA_TO_DEVICE);
 159                         } else {
 160                                 dma_unmap_page(dev, buff->pa, buff->len,
 161                                                DMA_TO_DEVICE);
 162                         }
 163                 }
 164
 165                 if (unlikely(buff->is_eop))
 166                         dev_kfree_skb_any(buff->skb);
 167
 168                 buff->pa = 0U;
 169                 buff->eop_index = 0xffffU;
 170         }
 171
 172         return !!budget;
 173 }
 174
 175 static void aq_rx_checksum(struct aq_ring_s *self,
 176                            struct aq_ring_buff_s *buff,
 177                            struct sk_buff *skb)
 178 {
 179         if (!(self->aq_nic->ndev->features & NETIF_F_RXCSUM))
 180                 return;
 181
 182         if (unlikely(buff->is_cso_err)) {
 183                 ++self->stats.rx.errors;
 184                 skb->ip_summed = CHECKSUM_NONE;
 185                 return;
 186         }
 187         if (buff->is_ip_cso) {
 188                 __skb_incr_checksum_unnecessary(skb);
 189                 if (buff->is_udp_cso || buff->is_tcp_cso)
 190                         __skb_incr_checksum_unnecessary(skb);
 191         } else {
 192                 skb->ip_summed = CHECKSUM_NONE;
 193         }
 194 }
 195
 196 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
 197 int aq_ring_rx_clean(struct aq_ring_s *self,
 198                      struct napi_struct *napi,
 199                      int *work_done,
 200                      int budget)
 201 {
 202         struct net_device *ndev = aq_nic_get_ndev(self->aq_nic);
 203         int err = 0;
 204         bool is_rsc_completed = true;
 205
 206         for (; (self->sw_head != self->hw_head) && budget;
 207                 self->sw_head = aq_ring_next_dx(self, self->sw_head),
 208                 --budget, ++(*work_done)) {
 209                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 210                 struct sk_buff *skb = NULL;
 211                 unsigned int next_ = 0U;
 212                 unsigned int i = 0U;
 213                 struct aq_ring_buff_s *buff_ = NULL;
 214
 215                 if (buff->is_error) {
 216                         __free_pages(buff->page, 0);
 217                         continue;
 218                 }
 219
 220                 if (buff->is_cleaned)
 221                         continue;
 222
 223                 if (!buff->is_eop) {
 224                         for (next_ = buff->next,
 225                              buff_ = &self->buff_ring[next_]; true;
 226                              next_ = buff_->next,
 227                              buff_ = &self->buff_ring[next_]) {
 228                                 is_rsc_completed =
 229                                         aq_ring_dx_in_range(self->sw_head,
 230                                                             next_,
 231                                                             self->hw_head);
 232
 233                                 if (unlikely(!is_rsc_completed)) {
 234                                         is_rsc_completed = false;
 235                                         break;
 236                                 }
 237
 238                                 if (buff_->is_eop)
 239                                         break;
 240                         }
 241
 242                         if (!is_rsc_completed) {
 243                                 err = 0;
 244                                 goto err_exit;
 245                         }
 246                 }
 247
 248                 /* for single fragment packets use build_skb() */
 249                 if (buff->is_eop &&
 250                     buff->len <= AQ_CFG_RX_FRAME_MAX - AQ_SKB_ALIGN) {
 251                         skb = build_skb(page_address(buff->page),
 252                                         AQ_CFG_RX_FRAME_MAX);
 253                         if (unlikely(!skb)) {
 254                                 err = -ENOMEM;
 255                                 goto err_exit;
 256                         }
 257
 258                         skb_put(skb, buff->len);
 259                 } else {
 260                         skb = netdev_alloc_skb(ndev, ETH_HLEN);
 261                         if (unlikely(!skb)) {
 262                                 err = -ENOMEM;
 263                                 goto err_exit;
 264                         }
 265                         skb_put(skb, ETH_HLEN);
 266                         memcpy(skb->data, page_address(buff->page), ETH_HLEN);
 267
 268                         skb_add_rx_frag(skb, 0, buff->page, ETH_HLEN,
 269                                         buff->len - ETH_HLEN,
 270                                         SKB_TRUESIZE(buff->len - ETH_HLEN));
 271
 272                         if (!buff->is_eop) {
 273                                 for (i = 1U, next_ = buff->next,
 274                                      buff_ = &self->buff_ring[next_];
 275                                      true; next_ = buff_->next,
 276                                      buff_ = &self->buff_ring[next_], ++i) {
 277                                         skb_add_rx_frag(skb, i,
 278                                                         buff_->page, 0,
 279                                                         buff_->len,
 280                                                         SKB_TRUESIZE(buff->len -
 281                                                         ETH_HLEN));
 282                                         buff_->is_cleaned = 1;
 283
 284                                         if (buff_->is_eop)
 285                                                 break;
 286                                 }
 287                         }
 288                 }
 289
 290                 skb->protocol = eth_type_trans(skb, ndev);
 291
 292                 aq_rx_checksum(self, buff, skb);
 293
 294                 skb_set_hash(skb, buff->rss_hash,
 295                              buff->is_hash_l4 ? PKT_HASH_TYPE_L4 :
 296                              PKT_HASH_TYPE_NONE);
 297
 298                 skb_record_rx_queue(skb, self->idx);
 299
 300                 ++self->stats.rx.packets;
 301                 self->stats.rx.bytes += skb->len;
 302
 303                 napi_gro_receive(napi, skb);
 304         }
 305
 306 err_exit:
 307         return err;
 308 }
 309
 310 int aq_ring_rx_fill(struct aq_ring_s *self)
 311 {
 312         unsigned int pages_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE +
 313                 (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1;
 314         struct aq_ring_buff_s *buff = NULL;
 315         int err = 0;
 316         int i = 0;
 317
 318         for (i = aq_ring_avail_dx(self); i--;
 319                 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) {
 320                 buff = &self->buff_ring[self->sw_tail];
 321
 322                 buff->flags = 0U;
 323                 buff->len = AQ_CFG_RX_FRAME_MAX;
 324
 325                 buff->page = alloc_pages(GFP_ATOMIC | __GFP_COMP, pages_order);
 326                 if (!buff->page) {
 327                         err = -ENOMEM;
 328                         goto err_exit;
 329                 }
 330
 331                 buff->pa = dma_map_page(aq_nic_get_dev(self->aq_nic),
 332                                         buff->page, 0,
 333                                         AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE);
 334
 335                 if (dma_mapping_error(aq_nic_get_dev(self->aq_nic), buff->pa)) {
 336                         err = -ENOMEM;
 337                         goto err_exit;
 338                 }
 339
 340                 buff = NULL;
 341         }
 342
 343 err_exit:
 344         if (err < 0) {
 345                 if (buff && buff->page)
 346                         __free_pages(buff->page, 0);
 347         }
 348
 349         return err;
 350 }
 351
 352 void aq_ring_rx_deinit(struct aq_ring_s *self)
 353 {
 354         if (!self)
 355                 goto err_exit;
 356
 357         for (; self->sw_head != self->sw_tail;
 358                 self->sw_head = aq_ring_next_dx(self, self->sw_head)) {
 359                 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
 360
 361                 dma_unmap_page(aq_nic_get_dev(self->aq_nic), buff->pa,
 362                                AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE);
 363
 364                 __free_pages(buff->page, 0);
 365         }
 366
 367 err_exit:;
 368 }
 369
 370 void aq_ring_free(struct aq_ring_s *self)
 371 {
 372         if (!self)
 373                 goto err_exit;
 374
 375         kfree(self->buff_ring);
 376
 377         if (self->dx_ring)
 378                 dma_free_coherent(aq_nic_get_dev(self->aq_nic),
 379                                   self->size * self->dx_size, self->dx_ring,
 380                                   self->dx_ring_pa);
 381
 382 err_exit:;
 383 }