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 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) 176 int aq_ring_rx_clean(struct aq_ring_s *self, 177 struct napi_struct *napi, 178 int *work_done, 179 int budget) 180 { 181 struct net_device *ndev = aq_nic_get_ndev(self->aq_nic); 182 int err = 0; 183 bool is_rsc_completed = true; 184 185 for (; (self->sw_head != self->hw_head) && budget; 186 self->sw_head = aq_ring_next_dx(self, self->sw_head), 187 --budget, ++(*work_done)) { 188 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 189 struct sk_buff *skb = NULL; 190 unsigned int next_ = 0U; 191 unsigned int i = 0U; 192 struct aq_ring_buff_s *buff_ = NULL; 193 194 if (buff->is_error) { 195 __free_pages(buff->page, 0); 196 continue; 197 } 198 199 if (buff->is_cleaned) 200 continue; 201 202 if (!buff->is_eop) { 203 for (next_ = buff->next, 204 buff_ = &self->buff_ring[next_]; true; 205 next_ = buff_->next, 206 buff_ = &self->buff_ring[next_]) { 207 is_rsc_completed = 208 aq_ring_dx_in_range(self->sw_head, 209 next_, 210 self->hw_head); 211 212 if (unlikely(!is_rsc_completed)) { 213 is_rsc_completed = false; 214 break; 215 } 216 217 if (buff_->is_eop) 218 break; 219 } 220 221 if (!is_rsc_completed) { 222 err = 0; 223 goto err_exit; 224 } 225 } 226 227 /* for single fragment packets use build_skb() */ 228 if (buff->is_eop) { 229 skb = build_skb(page_address(buff->page), 230 buff->len + AQ_SKB_ALIGN); 231 if (unlikely(!skb)) { 232 err = -ENOMEM; 233 goto err_exit; 234 } 235 236 skb_put(skb, buff->len); 237 } else { 238 skb = netdev_alloc_skb(ndev, ETH_HLEN); 239 if (unlikely(!skb)) { 240 err = -ENOMEM; 241 goto err_exit; 242 } 243 skb_put(skb, ETH_HLEN); 244 memcpy(skb->data, page_address(buff->page), ETH_HLEN); 245 246 skb_add_rx_frag(skb, 0, buff->page, ETH_HLEN, 247 buff->len - ETH_HLEN, 248 SKB_TRUESIZE(buff->len - ETH_HLEN)); 249 250 for (i = 1U, next_ = buff->next, 251 buff_ = &self->buff_ring[next_]; true; 252 next_ = buff_->next, 253 buff_ = &self->buff_ring[next_], ++i) { 254 skb_add_rx_frag(skb, i, buff_->page, 0, 255 buff_->len, 256 SKB_TRUESIZE(buff->len - 257 ETH_HLEN)); 258 buff_->is_cleaned = 1; 259 260 if (buff_->is_eop) 261 break; 262 } 263 } 264 265 skb->protocol = eth_type_trans(skb, ndev); 266 if (unlikely(buff->is_cso_err)) { 267 ++self->stats.rx.errors; 268 skb->ip_summed = CHECKSUM_NONE; 269 } else { 270 if (buff->is_ip_cso) { 271 __skb_incr_checksum_unnecessary(skb); 272 if (buff->is_udp_cso || buff->is_tcp_cso) 273 __skb_incr_checksum_unnecessary(skb); 274 } else { 275 skb->ip_summed = CHECKSUM_NONE; 276 } 277 } 278 279 skb_set_hash(skb, buff->rss_hash, 280 buff->is_hash_l4 ? PKT_HASH_TYPE_L4 : 281 PKT_HASH_TYPE_NONE); 282 283 skb_record_rx_queue(skb, self->idx); 284 285 ++self->stats.rx.packets; 286 self->stats.rx.bytes += skb->len; 287 288 napi_gro_receive(napi, skb); 289 } 290 291 err_exit: 292 return err; 293 } 294 295 int aq_ring_rx_fill(struct aq_ring_s *self) 296 { 297 unsigned int pages_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE + 298 (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1; 299 struct aq_ring_buff_s *buff = NULL; 300 int err = 0; 301 int i = 0; 302 303 for (i = aq_ring_avail_dx(self); i--; 304 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) { 305 buff = &self->buff_ring[self->sw_tail]; 306 307 buff->flags = 0U; 308 buff->len = AQ_CFG_RX_FRAME_MAX; 309 310 buff->page = alloc_pages(GFP_ATOMIC | __GFP_COMP, pages_order); 311 if (!buff->page) { 312 err = -ENOMEM; 313 goto err_exit; 314 } 315 316 buff->pa = dma_map_page(aq_nic_get_dev(self->aq_nic), 317 buff->page, 0, 318 AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE); 319 320 if (dma_mapping_error(aq_nic_get_dev(self->aq_nic), buff->pa)) { 321 err = -ENOMEM; 322 goto err_exit; 323 } 324 325 buff = NULL; 326 } 327 328 err_exit: 329 if (err < 0) { 330 if (buff && buff->page) 331 __free_pages(buff->page, 0); 332 } 333 334 return err; 335 } 336 337 void aq_ring_rx_deinit(struct aq_ring_s *self) 338 { 339 if (!self) 340 goto err_exit; 341 342 for (; self->sw_head != self->sw_tail; 343 self->sw_head = aq_ring_next_dx(self, self->sw_head)) { 344 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 345 346 dma_unmap_page(aq_nic_get_dev(self->aq_nic), buff->pa, 347 AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE); 348 349 __free_pages(buff->page, 0); 350 } 351 352 err_exit:; 353 } 354 355 void aq_ring_free(struct aq_ring_s *self) 356 { 357 if (!self) 358 goto err_exit; 359 360 kfree(self->buff_ring); 361 362 if (self->dx_ring) 363 dma_free_coherent(aq_nic_get_dev(self->aq_nic), 364 self->size * self->dx_size, self->dx_ring, 365 self->dx_ring_pa); 366 367 err_exit:; 368 } 369