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 void aq_ring_tx_clean(struct aq_ring_s *self) 140 { 141 struct device *dev = aq_nic_get_dev(self->aq_nic); 142 143 for (; self->sw_head != self->hw_head; 144 self->sw_head = aq_ring_next_dx(self, self->sw_head)) { 145 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 146 147 if (likely(buff->is_mapped)) { 148 if (unlikely(buff->is_sop)) { 149 if (!buff->is_eop && 150 buff->eop_index != 0xffffU && 151 (!aq_ring_dx_in_range(self->sw_head, 152 buff->eop_index, 153 self->hw_head))) 154 break; 155 156 dma_unmap_single(dev, buff->pa, buff->len, 157 DMA_TO_DEVICE); 158 } else { 159 dma_unmap_page(dev, buff->pa, buff->len, 160 DMA_TO_DEVICE); 161 } 162 } 163 164 if (unlikely(buff->is_eop)) 165 dev_kfree_skb_any(buff->skb); 166 167 buff->pa = 0U; 168 buff->eop_index = 0xffffU; 169 } 170 } 171 172 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) 173 int aq_ring_rx_clean(struct aq_ring_s *self, 174 struct napi_struct *napi, 175 int *work_done, 176 int budget) 177 { 178 struct net_device *ndev = aq_nic_get_ndev(self->aq_nic); 179 int err = 0; 180 bool is_rsc_completed = true; 181 182 for (; (self->sw_head != self->hw_head) && budget; 183 self->sw_head = aq_ring_next_dx(self, self->sw_head), 184 --budget, ++(*work_done)) { 185 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 186 struct sk_buff *skb = NULL; 187 unsigned int next_ = 0U; 188 unsigned int i = 0U; 189 struct aq_ring_buff_s *buff_ = NULL; 190 191 if (buff->is_error) { 192 __free_pages(buff->page, 0); 193 continue; 194 } 195 196 if (buff->is_cleaned) 197 continue; 198 199 if (!buff->is_eop) { 200 for (next_ = buff->next, 201 buff_ = &self->buff_ring[next_]; true; 202 next_ = buff_->next, 203 buff_ = &self->buff_ring[next_]) { 204 is_rsc_completed = 205 aq_ring_dx_in_range(self->sw_head, 206 next_, 207 self->hw_head); 208 209 if (unlikely(!is_rsc_completed)) { 210 is_rsc_completed = false; 211 break; 212 } 213 214 if (buff_->is_eop) 215 break; 216 } 217 218 if (!is_rsc_completed) { 219 err = 0; 220 goto err_exit; 221 } 222 } 223 224 /* for single fragment packets use build_skb() */ 225 if (buff->is_eop) { 226 skb = build_skb(page_address(buff->page), 227 buff->len + AQ_SKB_ALIGN); 228 if (unlikely(!skb)) { 229 err = -ENOMEM; 230 goto err_exit; 231 } 232 233 skb_put(skb, buff->len); 234 } else { 235 skb = netdev_alloc_skb(ndev, ETH_HLEN); 236 if (unlikely(!skb)) { 237 err = -ENOMEM; 238 goto err_exit; 239 } 240 skb_put(skb, ETH_HLEN); 241 memcpy(skb->data, page_address(buff->page), ETH_HLEN); 242 243 skb_add_rx_frag(skb, 0, buff->page, ETH_HLEN, 244 buff->len - ETH_HLEN, 245 SKB_TRUESIZE(buff->len - ETH_HLEN)); 246 247 for (i = 1U, next_ = buff->next, 248 buff_ = &self->buff_ring[next_]; true; 249 next_ = buff_->next, 250 buff_ = &self->buff_ring[next_], ++i) { 251 skb_add_rx_frag(skb, i, buff_->page, 0, 252 buff_->len, 253 SKB_TRUESIZE(buff->len - 254 ETH_HLEN)); 255 buff_->is_cleaned = 1; 256 257 if (buff_->is_eop) 258 break; 259 } 260 } 261 262 skb->protocol = eth_type_trans(skb, ndev); 263 if (unlikely(buff->is_cso_err)) { 264 ++self->stats.rx.errors; 265 skb->ip_summed = CHECKSUM_NONE; 266 } else { 267 if (buff->is_ip_cso) { 268 __skb_incr_checksum_unnecessary(skb); 269 if (buff->is_udp_cso || buff->is_tcp_cso) 270 __skb_incr_checksum_unnecessary(skb); 271 } else { 272 skb->ip_summed = CHECKSUM_NONE; 273 } 274 } 275 276 skb_set_hash(skb, buff->rss_hash, 277 buff->is_hash_l4 ? PKT_HASH_TYPE_L4 : 278 PKT_HASH_TYPE_NONE); 279 280 skb_record_rx_queue(skb, self->idx); 281 282 ++self->stats.rx.packets; 283 self->stats.rx.bytes += skb->len; 284 285 napi_gro_receive(napi, skb); 286 } 287 288 err_exit: 289 return err; 290 } 291 292 int aq_ring_rx_fill(struct aq_ring_s *self) 293 { 294 unsigned int pages_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE + 295 (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1; 296 struct aq_ring_buff_s *buff = NULL; 297 int err = 0; 298 int i = 0; 299 300 for (i = aq_ring_avail_dx(self); i--; 301 self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) { 302 buff = &self->buff_ring[self->sw_tail]; 303 304 buff->flags = 0U; 305 buff->len = AQ_CFG_RX_FRAME_MAX; 306 307 buff->page = alloc_pages(GFP_ATOMIC | __GFP_COMP, pages_order); 308 if (!buff->page) { 309 err = -ENOMEM; 310 goto err_exit; 311 } 312 313 buff->pa = dma_map_page(aq_nic_get_dev(self->aq_nic), 314 buff->page, 0, 315 AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE); 316 317 if (dma_mapping_error(aq_nic_get_dev(self->aq_nic), buff->pa)) { 318 err = -ENOMEM; 319 goto err_exit; 320 } 321 322 buff = NULL; 323 } 324 325 err_exit: 326 if (err < 0) { 327 if (buff && buff->page) 328 __free_pages(buff->page, 0); 329 } 330 331 return err; 332 } 333 334 void aq_ring_rx_deinit(struct aq_ring_s *self) 335 { 336 if (!self) 337 goto err_exit; 338 339 for (; self->sw_head != self->sw_tail; 340 self->sw_head = aq_ring_next_dx(self, self->sw_head)) { 341 struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head]; 342 343 dma_unmap_page(aq_nic_get_dev(self->aq_nic), buff->pa, 344 AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE); 345 346 __free_pages(buff->page, 0); 347 } 348 349 err_exit:; 350 } 351 352 void aq_ring_free(struct aq_ring_s *self) 353 { 354 if (!self) 355 goto err_exit; 356 357 kfree(self->buff_ring); 358 359 if (self->dx_ring) 360 dma_free_coherent(aq_nic_get_dev(self->aq_nic), 361 self->size * self->dx_size, self->dx_ring, 362 self->dx_ring_pa); 363 364 err_exit:; 365 } 366