1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * aQuantia Corporation Network Driver 4 * Copyright (C) 2014-2017 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 14 #include <linux/netdevice.h> 15 #include <linux/etherdevice.h> 16 17 static inline void aq_free_rxpage(struct aq_rxpage *rxpage, struct device *dev) 18 { 19 unsigned int len = PAGE_SIZE << rxpage->order; 20 21 dma_unmap_page(dev, rxpage->daddr, len, DMA_FROM_DEVICE); 22 23 /* Drop the ref for being in the ring. */ 24 __free_pages(rxpage->page, rxpage->order); 25 rxpage->page = NULL; 26 } 27 28 static int aq_get_rxpage(struct aq_rxpage *rxpage, unsigned int order, 29 struct device *dev) 30 { 31 struct page *page; 32 dma_addr_t daddr; 33 int ret = -ENOMEM; 34 35 page = dev_alloc_pages(order); 36 if (unlikely(!page)) 37 goto err_exit; 38 39 daddr = dma_map_page(dev, page, 0, PAGE_SIZE << order, 40 DMA_FROM_DEVICE); 41 42 if (unlikely(dma_mapping_error(dev, daddr))) 43 goto free_page; 44 45 rxpage->page = page; 46 rxpage->daddr = daddr; 47 rxpage->order = order; 48 rxpage->pg_off = 0; 49 50 return 0; 51 52 free_page: 53 __free_pages(page, order); 54 55 err_exit: 56 return ret; 57 } 58 59 static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf, 60 int order) 61 { 62 int ret; 63 64 if (rxbuf->rxdata.page) { 65 /* One means ring is the only user and can reuse */ 66 if (page_ref_count(rxbuf->rxdata.page) > 1) { 67 /* Try reuse buffer */ 68 rxbuf->rxdata.pg_off += AQ_CFG_RX_FRAME_MAX; 69 if (rxbuf->rxdata.pg_off + AQ_CFG_RX_FRAME_MAX <= 70 (PAGE_SIZE << order)) { 71 self->stats.rx.pg_flips++; 72 } else { 73 /* Buffer exhausted. We have other users and 74 * should release this page and realloc 75 */ 76 aq_free_rxpage(&rxbuf->rxdata, 77 aq_nic_get_dev(self->aq_nic)); 78 self->stats.rx.pg_losts++; 79 } 80 } else { 81 rxbuf->rxdata.pg_off = 0; 82 self->stats.rx.pg_reuses++; 83 } 84 } 85 86 if (!rxbuf->rxdata.page) { 87 ret = aq_get_rxpage(&rxbuf->rxdata, order, 88 aq_nic_get_dev(self->aq_nic)); 89 return ret; 90 } 91 92 return 0; 93 } 94 95 static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self, 96 struct aq_nic_s *aq_nic) 97 { 98 int err = 0; 99 100 self->buff_ring = 101 kcalloc(self->size, sizeof(struct aq_ring_buff_s), GFP_KERNEL); 102 103 if (!self->buff_ring) { 104 err = -ENOMEM; 105 goto err_exit; 106 } 107 self->dx_ring = dma_alloc_coherent(aq_nic_get_dev(aq_nic), 108 self->size * self->dx_size, 109 &self->dx_ring_pa, GFP_KERNEL); 110 if (!self->dx_ring) { 111 err = -ENOMEM; 112 goto err_exit; 113 } 114 115 err_exit: 116 if (err < 0) { 117 aq_ring_free(self); 118 self = NULL; 119 } 120 return self; 121 } 122 123 struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self, 124 struct aq_nic_s *aq_nic, 125 unsigned int idx, 126 struct aq_nic_cfg_s *aq_nic_cfg) 127 { 128 int err = 0; 129 130 self->aq_nic = aq_nic; 131 self->idx = idx; 132 self->size = aq_nic_cfg->txds; 133 self->dx_size = aq_nic_cfg->aq_hw_caps->txd_size; 134 135 self = aq_ring_alloc(self, aq_nic); 136 if (!self) { 137 err = -ENOMEM; 138 goto err_exit; 139 } 140 141 err_exit: 142 if (err < 0) { 143 aq_ring_free(self); 144 self = NULL; 145 } 146 return self; 147 } 148 149 struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self, 150 struct aq_nic_s *aq_nic, 151 unsigned int idx, 152 struct aq_nic_cfg_s *aq_nic_cfg) 153 { 154 int err = 0; 155 156 self->aq_nic = aq_nic; 157 self->idx = idx; 158 self->size = aq_nic_cfg->rxds; 159 self->dx_size = aq_nic_cfg->aq_hw_caps->rxd_size; 160 self->page_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE + 161 (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1; 162 163 if (aq_nic_cfg->rxpageorder > self->page_order) 164 self->page_order = aq_nic_cfg->rxpageorder; 165 166 self = aq_ring_alloc(self, aq_nic); 167 if (!self) { 168 err = -ENOMEM; 169 goto err_exit; 170 } 171 172 err_exit: 173 if (err < 0) { 174 aq_ring_free(self); 175 self = NULL; 176 } 177 return self; 178 } 179 180 int aq_ring_init(struct aq_ring_s *self) 181 { 182 self->hw_head = 0; 183 self->sw_head = 0; 184 self->sw_tail = 0; 185 return 0; 186 } 187 188 static inline bool aq_ring_dx_in_range(unsigned int h, unsigned int i, 189 unsigned int t) 190 { 191 return (h < t) ? ((h < i) && (i < t)) : ((h < i) || (i < t)); 192 } 193 194 void aq_ring_update_queue_state(struct aq_ring_s *ring) 195 { 196 if (aq_ring_avail_dx(ring) <= AQ_CFG_SKB_FRAGS_MAX) 197 aq_ring_queue_stop(ring); 198 else if (aq_ring_avail_dx(ring) > AQ_CFG_RESTART_DESC_THRES) 199 aq_ring_queue_wake(ring); 200 } 201 202 void aq_ring_queue_wake(struct aq_ring_s *ring) 203 { 204 struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic); 205 206 if (__netif_subqueue_stopped(ndev, ring->idx)) { 207 netif_wake_subqueue(ndev, ring->idx); 208 ring->stats.tx.queue_restarts++; 209 } 210 } 211 212 void aq_ring_queue_stop(struct aq_ring_s *ring) 213 { 214 struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic); 215 216 if (!__netif_subqueue_stopped(ndev, ring->idx)) 217 netif_stop_subqueue(ndev, ring->idx); 218 } 219 220 bool aq_ring_tx_clean(struct aq_ring_s *self) 221 { 222 struct device *dev = aq_nic_get_dev(self->aq_nic); 223 unsigned int budget; 224 225 for (budget = AQ_CFG_TX_CLEAN_BUDGET; 226 budget && self->sw_head != self->hw_head; budget--) { 227 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 228 229 if (likely(buff->is_mapped)) { 230 if (unlikely(buff->is_sop)) { 231 if (!buff->is_eop && 232 buff->eop_index != 0xffffU && 233 (!aq_ring_dx_in_range(self->sw_head, 234 buff->eop_index, 235 self->hw_head))) 236 break; 237 238 dma_unmap_single(dev, buff->pa, buff->len, 239 DMA_TO_DEVICE); 240 } else { 241 dma_unmap_page(dev, buff->pa, buff->len, 242 DMA_TO_DEVICE); 243 } 244 } 245 246 if (unlikely(buff->is_eop)) 247 dev_kfree_skb_any(buff->skb); 248 249 buff->pa = 0U; 250 buff->eop_index = 0xffffU; 251 self->sw_head = aq_ring_next_dx(self, self->sw_head); 252 } 253 254 return !!budget; 255 } 256 257 static void aq_rx_checksum(struct aq_ring_s *self, 258 struct aq_ring_buff_s *buff, 259 struct sk_buff *skb) 260 { 261 if (!(self->aq_nic->ndev->features & NETIF_F_RXCSUM)) 262 return; 263 264 if (unlikely(buff->is_cso_err)) { 265 ++self->stats.rx.errors; 266 skb->ip_summed = CHECKSUM_NONE; 267 return; 268 } 269 if (buff->is_ip_cso) { 270 __skb_incr_checksum_unnecessary(skb); 271 } else { 272 skb->ip_summed = CHECKSUM_NONE; 273 } 274 275 if (buff->is_udp_cso || buff->is_tcp_cso) 276 __skb_incr_checksum_unnecessary(skb); 277 } 278 279 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) 280 int aq_ring_rx_clean(struct aq_ring_s *self, 281 struct napi_struct *napi, 282 int *work_done, 283 int budget) 284 { 285 struct net_device *ndev = aq_nic_get_ndev(self->aq_nic); 286 bool is_rsc_completed = true; 287 int err = 0; 288 289 for (; (self->sw_head != self->hw_head) && budget; 290 self->sw_head = aq_ring_next_dx(self, self->sw_head), 291 --budget, ++(*work_done)) { 292 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 293 struct aq_ring_buff_s *buff_ = NULL; 294 struct sk_buff *skb = NULL; 295 unsigned int next_ = 0U; 296 unsigned int i = 0U; 297 u16 hdr_len; 298 299 if (buff->is_cleaned) 300 continue; 301 302 if (!buff->is_eop) { 303 buff_ = buff; 304 do { 305 next_ = buff_->next, 306 buff_ = &self->buff_ring[next_]; 307 is_rsc_completed = 308 aq_ring_dx_in_range(self->sw_head, 309 next_, 310 self->hw_head); 311 312 if (unlikely(!is_rsc_completed)) 313 break; 314 315 buff->is_error |= buff_->is_error; 316 317 } while (!buff_->is_eop); 318 319 if (!is_rsc_completed) { 320 err = 0; 321 goto err_exit; 322 } 323 if (buff->is_error) { 324 buff_ = buff; 325 do { 326 next_ = buff_->next, 327 buff_ = &self->buff_ring[next_]; 328 329 buff_->is_cleaned = true; 330 } while (!buff_->is_eop); 331 332 ++self->stats.rx.errors; 333 continue; 334 } 335 } 336 337 if (buff->is_error) { 338 ++self->stats.rx.errors; 339 continue; 340 } 341 342 dma_sync_single_range_for_cpu(aq_nic_get_dev(self->aq_nic), 343 buff->rxdata.daddr, 344 buff->rxdata.pg_off, 345 buff->len, DMA_FROM_DEVICE); 346 347 /* for single fragment packets use build_skb() */ 348 if (buff->is_eop && 349 buff->len <= AQ_CFG_RX_FRAME_MAX - AQ_SKB_ALIGN) { 350 skb = build_skb(aq_buf_vaddr(&buff->rxdata), 351 AQ_CFG_RX_FRAME_MAX); 352 if (unlikely(!skb)) { 353 err = -ENOMEM; 354 goto err_exit; 355 } 356 skb_put(skb, buff->len); 357 page_ref_inc(buff->rxdata.page); 358 } else { 359 skb = napi_alloc_skb(napi, AQ_CFG_RX_HDR_SIZE); 360 if (unlikely(!skb)) { 361 err = -ENOMEM; 362 goto err_exit; 363 } 364 365 hdr_len = buff->len; 366 if (hdr_len > AQ_CFG_RX_HDR_SIZE) 367 hdr_len = eth_get_headlen(skb->dev, 368 aq_buf_vaddr(&buff->rxdata), 369 AQ_CFG_RX_HDR_SIZE); 370 371 memcpy(__skb_put(skb, hdr_len), aq_buf_vaddr(&buff->rxdata), 372 ALIGN(hdr_len, sizeof(long))); 373 374 if (buff->len - hdr_len > 0) { 375 skb_add_rx_frag(skb, 0, buff->rxdata.page, 376 buff->rxdata.pg_off + hdr_len, 377 buff->len - hdr_len, 378 AQ_CFG_RX_FRAME_MAX); 379 page_ref_inc(buff->rxdata.page); 380 } 381 382 if (!buff->is_eop) { 383 buff_ = buff; 384 i = 1U; 385 do { 386 next_ = buff_->next, 387 buff_ = &self->buff_ring[next_]; 388 389 dma_sync_single_range_for_cpu( 390 aq_nic_get_dev(self->aq_nic), 391 buff_->rxdata.daddr, 392 buff_->rxdata.pg_off, 393 buff_->len, 394 DMA_FROM_DEVICE); 395 skb_add_rx_frag(skb, i++, 396 buff_->rxdata.page, 397 buff_->rxdata.pg_off, 398 buff_->len, 399 AQ_CFG_RX_FRAME_MAX); 400 page_ref_inc(buff_->rxdata.page); 401 buff_->is_cleaned = 1; 402 403 buff->is_ip_cso &= buff_->is_ip_cso; 404 buff->is_udp_cso &= buff_->is_udp_cso; 405 buff->is_tcp_cso &= buff_->is_tcp_cso; 406 buff->is_cso_err |= buff_->is_cso_err; 407 408 } while (!buff_->is_eop); 409 } 410 } 411 412 if (buff->is_vlan) 413 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), 414 buff->vlan_rx_tag); 415 416 skb->protocol = eth_type_trans(skb, ndev); 417 418 aq_rx_checksum(self, buff, skb); 419 420 skb_set_hash(skb, buff->rss_hash, 421 buff->is_hash_l4 ? PKT_HASH_TYPE_L4 : 422 PKT_HASH_TYPE_NONE); 423 424 skb_record_rx_queue(skb, self->idx); 425 426 ++self->stats.rx.packets; 427 self->stats.rx.bytes += skb->len; 428 429 napi_gro_receive(napi, skb); 430 } 431 432 err_exit: 433 return err; 434 } 435 436 int aq_ring_rx_fill(struct aq_ring_s *self) 437 { 438 unsigned int page_order = self->page_order; 439 struct aq_ring_buff_s *buff = NULL; 440 int err = 0; 441 int i = 0; 442 443 if (aq_ring_avail_dx(self) < min_t(unsigned int, AQ_CFG_RX_REFILL_THRES, 444 self->size / 2)) 445 return err; 446 447 for (i = aq_ring_avail_dx(self); i--; 448 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) { 449 buff = &self->buff_ring[self->sw_tail]; 450 451 buff->flags = 0U; 452 buff->len = AQ_CFG_RX_FRAME_MAX; 453 454 err = aq_get_rxpages(self, buff, page_order); 455 if (err) 456 goto err_exit; 457 458 buff->pa = aq_buf_daddr(&buff->rxdata); 459 buff = NULL; 460 } 461 462 err_exit: 463 return err; 464 } 465 466 void aq_ring_rx_deinit(struct aq_ring_s *self) 467 { 468 if (!self) 469 goto err_exit; 470 471 for (; self->sw_head != self->sw_tail; 472 self->sw_head = aq_ring_next_dx(self, self->sw_head)) { 473 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 474 475 aq_free_rxpage(&buff->rxdata, aq_nic_get_dev(self->aq_nic)); 476 } 477 478 err_exit:; 479 } 480 481 void aq_ring_free(struct aq_ring_s *self) 482 { 483 if (!self) 484 goto err_exit; 485 486 kfree(self->buff_ring); 487 488 if (self->dx_ring) 489 dma_free_coherent(aq_nic_get_dev(self->aq_nic), 490 self->size * self->dx_size, self->dx_ring, 491 self->dx_ring_pa); 492 493 err_exit:; 494 } 495