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 buff->is_cso_err |= buff_->is_cso_err; 317 318 } while (!buff_->is_eop); 319 320 if (!is_rsc_completed) { 321 err = 0; 322 goto err_exit; 323 } 324 if (buff->is_error || buff->is_cso_err) { 325 buff_ = buff; 326 do { 327 next_ = buff_->next, 328 buff_ = &self->buff_ring[next_]; 329 330 buff_->is_cleaned = true; 331 } while (!buff_->is_eop); 332 333 ++self->stats.rx.errors; 334 continue; 335 } 336 } 337 338 if (buff->is_error) { 339 ++self->stats.rx.errors; 340 continue; 341 } 342 343 dma_sync_single_range_for_cpu(aq_nic_get_dev(self->aq_nic), 344 buff->rxdata.daddr, 345 buff->rxdata.pg_off, 346 buff->len, DMA_FROM_DEVICE); 347 348 /* for single fragment packets use build_skb() */ 349 if (buff->is_eop && 350 buff->len <= AQ_CFG_RX_FRAME_MAX - AQ_SKB_ALIGN) { 351 skb = build_skb(aq_buf_vaddr(&buff->rxdata), 352 AQ_CFG_RX_FRAME_MAX); 353 if (unlikely(!skb)) { 354 err = -ENOMEM; 355 goto err_exit; 356 } 357 skb_put(skb, buff->len); 358 page_ref_inc(buff->rxdata.page); 359 } else { 360 skb = napi_alloc_skb(napi, AQ_CFG_RX_HDR_SIZE); 361 if (unlikely(!skb)) { 362 err = -ENOMEM; 363 goto err_exit; 364 } 365 366 hdr_len = buff->len; 367 if (hdr_len > AQ_CFG_RX_HDR_SIZE) 368 hdr_len = eth_get_headlen(skb->dev, 369 aq_buf_vaddr(&buff->rxdata), 370 AQ_CFG_RX_HDR_SIZE); 371 372 memcpy(__skb_put(skb, hdr_len), aq_buf_vaddr(&buff->rxdata), 373 ALIGN(hdr_len, sizeof(long))); 374 375 if (buff->len - hdr_len > 0) { 376 skb_add_rx_frag(skb, 0, buff->rxdata.page, 377 buff->rxdata.pg_off + hdr_len, 378 buff->len - hdr_len, 379 AQ_CFG_RX_FRAME_MAX); 380 page_ref_inc(buff->rxdata.page); 381 } 382 383 if (!buff->is_eop) { 384 buff_ = buff; 385 i = 1U; 386 do { 387 next_ = buff_->next, 388 buff_ = &self->buff_ring[next_]; 389 390 dma_sync_single_range_for_cpu( 391 aq_nic_get_dev(self->aq_nic), 392 buff_->rxdata.daddr, 393 buff_->rxdata.pg_off, 394 buff_->len, 395 DMA_FROM_DEVICE); 396 skb_add_rx_frag(skb, i++, 397 buff_->rxdata.page, 398 buff_->rxdata.pg_off, 399 buff_->len, 400 AQ_CFG_RX_FRAME_MAX); 401 page_ref_inc(buff_->rxdata.page); 402 buff_->is_cleaned = 1; 403 404 buff->is_ip_cso &= buff_->is_ip_cso; 405 buff->is_udp_cso &= buff_->is_udp_cso; 406 buff->is_tcp_cso &= buff_->is_tcp_cso; 407 buff->is_cso_err |= buff_->is_cso_err; 408 409 } while (!buff_->is_eop); 410 } 411 } 412 413 if (buff->is_vlan) 414 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), 415 buff->vlan_rx_tag); 416 417 skb->protocol = eth_type_trans(skb, ndev); 418 419 aq_rx_checksum(self, buff, skb); 420 421 skb_set_hash(skb, buff->rss_hash, 422 buff->is_hash_l4 ? PKT_HASH_TYPE_L4 : 423 PKT_HASH_TYPE_NONE); 424 425 skb_record_rx_queue(skb, self->idx); 426 427 ++self->stats.rx.packets; 428 self->stats.rx.bytes += skb->len; 429 430 napi_gro_receive(napi, skb); 431 } 432 433 err_exit: 434 return err; 435 } 436 437 int aq_ring_rx_fill(struct aq_ring_s *self) 438 { 439 unsigned int page_order = self->page_order; 440 struct aq_ring_buff_s *buff = NULL; 441 int err = 0; 442 int i = 0; 443 444 if (aq_ring_avail_dx(self) < min_t(unsigned int, AQ_CFG_RX_REFILL_THRES, 445 self->size / 2)) 446 return err; 447 448 for (i = aq_ring_avail_dx(self); i--; 449 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) { 450 buff = &self->buff_ring[self->sw_tail]; 451 452 buff->flags = 0U; 453 buff->len = AQ_CFG_RX_FRAME_MAX; 454 455 err = aq_get_rxpages(self, buff, page_order); 456 if (err) 457 goto err_exit; 458 459 buff->pa = aq_buf_daddr(&buff->rxdata); 460 buff = NULL; 461 } 462 463 err_exit: 464 return err; 465 } 466 467 void aq_ring_rx_deinit(struct aq_ring_s *self) 468 { 469 if (!self) 470 goto err_exit; 471 472 for (; self->sw_head != self->sw_tail; 473 self->sw_head = aq_ring_next_dx(self, self->sw_head)) { 474 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 475 476 aq_free_rxpage(&buff->rxdata, aq_nic_get_dev(self->aq_nic)); 477 } 478 479 err_exit:; 480 } 481 482 void aq_ring_free(struct aq_ring_s *self) 483 { 484 if (!self) 485 goto err_exit; 486 487 kfree(self->buff_ring); 488 489 if (self->dx_ring) 490 dma_free_coherent(aq_nic_get_dev(self->aq_nic), 491 self->size * self->dx_size, self->dx_ring, 492 self->dx_ring_pa); 493 494 err_exit:; 495 } 496