1 /**************************************************************************** 2 * Driver for Solarflare network controllers and boards 3 * Copyright 2005-2006 Fen Systems Ltd. 4 * Copyright 2005-2013 Solarflare Communications Inc. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published 8 * by the Free Software Foundation, incorporated herein by reference. 9 */ 10 11 #include <linux/socket.h> 12 #include <linux/in.h> 13 #include <linux/slab.h> 14 #include <linux/ip.h> 15 #include <linux/ipv6.h> 16 #include <linux/tcp.h> 17 #include <linux/udp.h> 18 #include <linux/prefetch.h> 19 #include <linux/moduleparam.h> 20 #include <linux/iommu.h> 21 #include <net/ip.h> 22 #include <net/checksum.h> 23 #include "net_driver.h" 24 #include "efx.h" 25 #include "filter.h" 26 #include "nic.h" 27 #include "selftest.h" 28 #include "workarounds.h" 29 30 /* Preferred number of descriptors to fill at once */ 31 #define EF4_RX_PREFERRED_BATCH 8U 32 33 /* Number of RX buffers to recycle pages for. When creating the RX page recycle 34 * ring, this number is divided by the number of buffers per page to calculate 35 * the number of pages to store in the RX page recycle ring. 36 */ 37 #define EF4_RECYCLE_RING_SIZE_IOMMU 4096 38 #define EF4_RECYCLE_RING_SIZE_NOIOMMU (2 * EF4_RX_PREFERRED_BATCH) 39 40 /* Size of buffer allocated for skb header area. */ 41 #define EF4_SKB_HEADERS 128u 42 43 /* This is the percentage fill level below which new RX descriptors 44 * will be added to the RX descriptor ring. 45 */ 46 static unsigned int rx_refill_threshold; 47 48 /* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */ 49 #define EF4_RX_MAX_FRAGS DIV_ROUND_UP(EF4_MAX_FRAME_LEN(EF4_MAX_MTU), \ 50 EF4_RX_USR_BUF_SIZE) 51 52 /* 53 * RX maximum head room required. 54 * 55 * This must be at least 1 to prevent overflow, plus one packet-worth 56 * to allow pipelined receives. 57 */ 58 #define EF4_RXD_HEAD_ROOM (1 + EF4_RX_MAX_FRAGS) 59 60 static inline u8 *ef4_rx_buf_va(struct ef4_rx_buffer *buf) 61 { 62 return page_address(buf->page) + buf->page_offset; 63 } 64 65 static inline u32 ef4_rx_buf_hash(struct ef4_nic *efx, const u8 *eh) 66 { 67 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 68 return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_hash_offset)); 69 #else 70 const u8 *data = eh + efx->rx_packet_hash_offset; 71 return (u32)data[0] | 72 (u32)data[1] << 8 | 73 (u32)data[2] << 16 | 74 (u32)data[3] << 24; 75 #endif 76 } 77 78 static inline struct ef4_rx_buffer * 79 ef4_rx_buf_next(struct ef4_rx_queue *rx_queue, struct ef4_rx_buffer *rx_buf) 80 { 81 if (unlikely(rx_buf == ef4_rx_buffer(rx_queue, rx_queue->ptr_mask))) 82 return ef4_rx_buffer(rx_queue, 0); 83 else 84 return rx_buf + 1; 85 } 86 87 static inline void ef4_sync_rx_buffer(struct ef4_nic *efx, 88 struct ef4_rx_buffer *rx_buf, 89 unsigned int len) 90 { 91 dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len, 92 DMA_FROM_DEVICE); 93 } 94 95 void ef4_rx_config_page_split(struct ef4_nic *efx) 96 { 97 efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align, 98 EF4_RX_BUF_ALIGNMENT); 99 efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 : 100 ((PAGE_SIZE - sizeof(struct ef4_rx_page_state)) / 101 efx->rx_page_buf_step); 102 efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) / 103 efx->rx_bufs_per_page; 104 efx->rx_pages_per_batch = DIV_ROUND_UP(EF4_RX_PREFERRED_BATCH, 105 efx->rx_bufs_per_page); 106 } 107 108 /* Check the RX page recycle ring for a page that can be reused. */ 109 static struct page *ef4_reuse_page(struct ef4_rx_queue *rx_queue) 110 { 111 struct ef4_nic *efx = rx_queue->efx; 112 struct page *page; 113 struct ef4_rx_page_state *state; 114 unsigned index; 115 116 index = rx_queue->page_remove & rx_queue->page_ptr_mask; 117 page = rx_queue->page_ring[index]; 118 if (page == NULL) 119 return NULL; 120 121 rx_queue->page_ring[index] = NULL; 122 /* page_remove cannot exceed page_add. */ 123 if (rx_queue->page_remove != rx_queue->page_add) 124 ++rx_queue->page_remove; 125 126 /* If page_count is 1 then we hold the only reference to this page. */ 127 if (page_count(page) == 1) { 128 ++rx_queue->page_recycle_count; 129 return page; 130 } else { 131 state = page_address(page); 132 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, 133 PAGE_SIZE << efx->rx_buffer_order, 134 DMA_FROM_DEVICE); 135 put_page(page); 136 ++rx_queue->page_recycle_failed; 137 } 138 139 return NULL; 140 } 141 142 /** 143 * ef4_init_rx_buffers - create EF4_RX_BATCH page-based RX buffers 144 * 145 * @rx_queue: Efx RX queue 146 * 147 * This allocates a batch of pages, maps them for DMA, and populates 148 * struct ef4_rx_buffers for each one. Return a negative error code or 149 * 0 on success. If a single page can be used for multiple buffers, 150 * then the page will either be inserted fully, or not at all. 151 */ 152 static int ef4_init_rx_buffers(struct ef4_rx_queue *rx_queue, bool atomic) 153 { 154 struct ef4_nic *efx = rx_queue->efx; 155 struct ef4_rx_buffer *rx_buf; 156 struct page *page; 157 unsigned int page_offset; 158 struct ef4_rx_page_state *state; 159 dma_addr_t dma_addr; 160 unsigned index, count; 161 162 count = 0; 163 do { 164 page = ef4_reuse_page(rx_queue); 165 if (page == NULL) { 166 page = alloc_pages(__GFP_COMP | 167 (atomic ? GFP_ATOMIC : GFP_KERNEL), 168 efx->rx_buffer_order); 169 if (unlikely(page == NULL)) 170 return -ENOMEM; 171 dma_addr = 172 dma_map_page(&efx->pci_dev->dev, page, 0, 173 PAGE_SIZE << efx->rx_buffer_order, 174 DMA_FROM_DEVICE); 175 if (unlikely(dma_mapping_error(&efx->pci_dev->dev, 176 dma_addr))) { 177 __free_pages(page, efx->rx_buffer_order); 178 return -EIO; 179 } 180 state = page_address(page); 181 state->dma_addr = dma_addr; 182 } else { 183 state = page_address(page); 184 dma_addr = state->dma_addr; 185 } 186 187 dma_addr += sizeof(struct ef4_rx_page_state); 188 page_offset = sizeof(struct ef4_rx_page_state); 189 190 do { 191 index = rx_queue->added_count & rx_queue->ptr_mask; 192 rx_buf = ef4_rx_buffer(rx_queue, index); 193 rx_buf->dma_addr = dma_addr + efx->rx_ip_align; 194 rx_buf->page = page; 195 rx_buf->page_offset = page_offset + efx->rx_ip_align; 196 rx_buf->len = efx->rx_dma_len; 197 rx_buf->flags = 0; 198 ++rx_queue->added_count; 199 get_page(page); 200 dma_addr += efx->rx_page_buf_step; 201 page_offset += efx->rx_page_buf_step; 202 } while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE); 203 204 rx_buf->flags = EF4_RX_BUF_LAST_IN_PAGE; 205 } while (++count < efx->rx_pages_per_batch); 206 207 return 0; 208 } 209 210 /* Unmap a DMA-mapped page. This function is only called for the final RX 211 * buffer in a page. 212 */ 213 static void ef4_unmap_rx_buffer(struct ef4_nic *efx, 214 struct ef4_rx_buffer *rx_buf) 215 { 216 struct page *page = rx_buf->page; 217 218 if (page) { 219 struct ef4_rx_page_state *state = page_address(page); 220 dma_unmap_page(&efx->pci_dev->dev, 221 state->dma_addr, 222 PAGE_SIZE << efx->rx_buffer_order, 223 DMA_FROM_DEVICE); 224 } 225 } 226 227 static void ef4_free_rx_buffers(struct ef4_rx_queue *rx_queue, 228 struct ef4_rx_buffer *rx_buf, 229 unsigned int num_bufs) 230 { 231 do { 232 if (rx_buf->page) { 233 put_page(rx_buf->page); 234 rx_buf->page = NULL; 235 } 236 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf); 237 } while (--num_bufs); 238 } 239 240 /* Attempt to recycle the page if there is an RX recycle ring; the page can 241 * only be added if this is the final RX buffer, to prevent pages being used in 242 * the descriptor ring and appearing in the recycle ring simultaneously. 243 */ 244 static void ef4_recycle_rx_page(struct ef4_channel *channel, 245 struct ef4_rx_buffer *rx_buf) 246 { 247 struct page *page = rx_buf->page; 248 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel); 249 struct ef4_nic *efx = rx_queue->efx; 250 unsigned index; 251 252 /* Only recycle the page after processing the final buffer. */ 253 if (!(rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE)) 254 return; 255 256 index = rx_queue->page_add & rx_queue->page_ptr_mask; 257 if (rx_queue->page_ring[index] == NULL) { 258 unsigned read_index = rx_queue->page_remove & 259 rx_queue->page_ptr_mask; 260 261 /* The next slot in the recycle ring is available, but 262 * increment page_remove if the read pointer currently 263 * points here. 264 */ 265 if (read_index == index) 266 ++rx_queue->page_remove; 267 rx_queue->page_ring[index] = page; 268 ++rx_queue->page_add; 269 return; 270 } 271 ++rx_queue->page_recycle_full; 272 ef4_unmap_rx_buffer(efx, rx_buf); 273 put_page(rx_buf->page); 274 } 275 276 static void ef4_fini_rx_buffer(struct ef4_rx_queue *rx_queue, 277 struct ef4_rx_buffer *rx_buf) 278 { 279 /* Release the page reference we hold for the buffer. */ 280 if (rx_buf->page) 281 put_page(rx_buf->page); 282 283 /* If this is the last buffer in a page, unmap and free it. */ 284 if (rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE) { 285 ef4_unmap_rx_buffer(rx_queue->efx, rx_buf); 286 ef4_free_rx_buffers(rx_queue, rx_buf, 1); 287 } 288 rx_buf->page = NULL; 289 } 290 291 /* Recycle the pages that are used by buffers that have just been received. */ 292 static void ef4_recycle_rx_pages(struct ef4_channel *channel, 293 struct ef4_rx_buffer *rx_buf, 294 unsigned int n_frags) 295 { 296 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel); 297 298 do { 299 ef4_recycle_rx_page(channel, rx_buf); 300 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf); 301 } while (--n_frags); 302 } 303 304 static void ef4_discard_rx_packet(struct ef4_channel *channel, 305 struct ef4_rx_buffer *rx_buf, 306 unsigned int n_frags) 307 { 308 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel); 309 310 ef4_recycle_rx_pages(channel, rx_buf, n_frags); 311 312 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags); 313 } 314 315 /** 316 * ef4_fast_push_rx_descriptors - push new RX descriptors quickly 317 * @rx_queue: RX descriptor queue 318 * 319 * This will aim to fill the RX descriptor queue up to 320 * @rx_queue->@max_fill. If there is insufficient atomic 321 * memory to do so, a slow fill will be scheduled. 322 * 323 * The caller must provide serialisation (none is used here). In practise, 324 * this means this function must run from the NAPI handler, or be called 325 * when NAPI is disabled. 326 */ 327 void ef4_fast_push_rx_descriptors(struct ef4_rx_queue *rx_queue, bool atomic) 328 { 329 struct ef4_nic *efx = rx_queue->efx; 330 unsigned int fill_level, batch_size; 331 int space, rc = 0; 332 333 if (!rx_queue->refill_enabled) 334 return; 335 336 /* Calculate current fill level, and exit if we don't need to fill */ 337 fill_level = (rx_queue->added_count - rx_queue->removed_count); 338 EF4_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries); 339 if (fill_level >= rx_queue->fast_fill_trigger) 340 goto out; 341 342 /* Record minimum fill level */ 343 if (unlikely(fill_level < rx_queue->min_fill)) { 344 if (fill_level) 345 rx_queue->min_fill = fill_level; 346 } 347 348 batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page; 349 space = rx_queue->max_fill - fill_level; 350 EF4_BUG_ON_PARANOID(space < batch_size); 351 352 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, 353 "RX queue %d fast-filling descriptor ring from" 354 " level %d to level %d\n", 355 ef4_rx_queue_index(rx_queue), fill_level, 356 rx_queue->max_fill); 357 358 359 do { 360 rc = ef4_init_rx_buffers(rx_queue, atomic); 361 if (unlikely(rc)) { 362 /* Ensure that we don't leave the rx queue empty */ 363 if (rx_queue->added_count == rx_queue->removed_count) 364 ef4_schedule_slow_fill(rx_queue); 365 goto out; 366 } 367 } while ((space -= batch_size) >= batch_size); 368 369 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, 370 "RX queue %d fast-filled descriptor ring " 371 "to level %d\n", ef4_rx_queue_index(rx_queue), 372 rx_queue->added_count - rx_queue->removed_count); 373 374 out: 375 if (rx_queue->notified_count != rx_queue->added_count) 376 ef4_nic_notify_rx_desc(rx_queue); 377 } 378 379 void ef4_rx_slow_fill(struct timer_list *t) 380 { 381 struct ef4_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill); 382 383 /* Post an event to cause NAPI to run and refill the queue */ 384 ef4_nic_generate_fill_event(rx_queue); 385 ++rx_queue->slow_fill_count; 386 } 387 388 static void ef4_rx_packet__check_len(struct ef4_rx_queue *rx_queue, 389 struct ef4_rx_buffer *rx_buf, 390 int len) 391 { 392 struct ef4_nic *efx = rx_queue->efx; 393 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding; 394 395 if (likely(len <= max_len)) 396 return; 397 398 /* The packet must be discarded, but this is only a fatal error 399 * if the caller indicated it was 400 */ 401 rx_buf->flags |= EF4_RX_PKT_DISCARD; 402 403 if ((len > rx_buf->len) && EF4_WORKAROUND_8071(efx)) { 404 if (net_ratelimit()) 405 netif_err(efx, rx_err, efx->net_dev, 406 " RX queue %d seriously overlength " 407 "RX event (0x%x > 0x%x+0x%x). Leaking\n", 408 ef4_rx_queue_index(rx_queue), len, max_len, 409 efx->type->rx_buffer_padding); 410 ef4_schedule_reset(efx, RESET_TYPE_RX_RECOVERY); 411 } else { 412 if (net_ratelimit()) 413 netif_err(efx, rx_err, efx->net_dev, 414 " RX queue %d overlength RX event " 415 "(0x%x > 0x%x)\n", 416 ef4_rx_queue_index(rx_queue), len, max_len); 417 } 418 419 ef4_rx_queue_channel(rx_queue)->n_rx_overlength++; 420 } 421 422 /* Pass a received packet up through GRO. GRO can handle pages 423 * regardless of checksum state and skbs with a good checksum. 424 */ 425 static void 426 ef4_rx_packet_gro(struct ef4_channel *channel, struct ef4_rx_buffer *rx_buf, 427 unsigned int n_frags, u8 *eh) 428 { 429 struct napi_struct *napi = &channel->napi_str; 430 gro_result_t gro_result; 431 struct ef4_nic *efx = channel->efx; 432 struct sk_buff *skb; 433 434 skb = napi_get_frags(napi); 435 if (unlikely(!skb)) { 436 struct ef4_rx_queue *rx_queue; 437 438 rx_queue = ef4_channel_get_rx_queue(channel); 439 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags); 440 return; 441 } 442 443 if (efx->net_dev->features & NETIF_F_RXHASH) 444 skb_set_hash(skb, ef4_rx_buf_hash(efx, eh), 445 PKT_HASH_TYPE_L3); 446 skb->ip_summed = ((rx_buf->flags & EF4_RX_PKT_CSUMMED) ? 447 CHECKSUM_UNNECESSARY : CHECKSUM_NONE); 448 449 for (;;) { 450 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, 451 rx_buf->page, rx_buf->page_offset, 452 rx_buf->len); 453 rx_buf->page = NULL; 454 skb->len += rx_buf->len; 455 if (skb_shinfo(skb)->nr_frags == n_frags) 456 break; 457 458 rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf); 459 } 460 461 skb->data_len = skb->len; 462 skb->truesize += n_frags * efx->rx_buffer_truesize; 463 464 skb_record_rx_queue(skb, channel->rx_queue.core_index); 465 466 gro_result = napi_gro_frags(napi); 467 if (gro_result != GRO_DROP) 468 channel->irq_mod_score += 2; 469 } 470 471 /* Allocate and construct an SKB around page fragments */ 472 static struct sk_buff *ef4_rx_mk_skb(struct ef4_channel *channel, 473 struct ef4_rx_buffer *rx_buf, 474 unsigned int n_frags, 475 u8 *eh, int hdr_len) 476 { 477 struct ef4_nic *efx = channel->efx; 478 struct sk_buff *skb; 479 480 /* Allocate an SKB to store the headers */ 481 skb = netdev_alloc_skb(efx->net_dev, 482 efx->rx_ip_align + efx->rx_prefix_size + 483 hdr_len); 484 if (unlikely(skb == NULL)) { 485 atomic_inc(&efx->n_rx_noskb_drops); 486 return NULL; 487 } 488 489 EF4_BUG_ON_PARANOID(rx_buf->len < hdr_len); 490 491 memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size, 492 efx->rx_prefix_size + hdr_len); 493 skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size); 494 __skb_put(skb, hdr_len); 495 496 /* Append the remaining page(s) onto the frag list */ 497 if (rx_buf->len > hdr_len) { 498 rx_buf->page_offset += hdr_len; 499 rx_buf->len -= hdr_len; 500 501 for (;;) { 502 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, 503 rx_buf->page, rx_buf->page_offset, 504 rx_buf->len); 505 rx_buf->page = NULL; 506 skb->len += rx_buf->len; 507 skb->data_len += rx_buf->len; 508 if (skb_shinfo(skb)->nr_frags == n_frags) 509 break; 510 511 rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf); 512 } 513 } else { 514 __free_pages(rx_buf->page, efx->rx_buffer_order); 515 rx_buf->page = NULL; 516 n_frags = 0; 517 } 518 519 skb->truesize += n_frags * efx->rx_buffer_truesize; 520 521 /* Move past the ethernet header */ 522 skb->protocol = eth_type_trans(skb, efx->net_dev); 523 524 skb_mark_napi_id(skb, &channel->napi_str); 525 526 return skb; 527 } 528 529 void ef4_rx_packet(struct ef4_rx_queue *rx_queue, unsigned int index, 530 unsigned int n_frags, unsigned int len, u16 flags) 531 { 532 struct ef4_nic *efx = rx_queue->efx; 533 struct ef4_channel *channel = ef4_rx_queue_channel(rx_queue); 534 struct ef4_rx_buffer *rx_buf; 535 536 rx_queue->rx_packets++; 537 538 rx_buf = ef4_rx_buffer(rx_queue, index); 539 rx_buf->flags |= flags; 540 541 /* Validate the number of fragments and completed length */ 542 if (n_frags == 1) { 543 if (!(flags & EF4_RX_PKT_PREFIX_LEN)) 544 ef4_rx_packet__check_len(rx_queue, rx_buf, len); 545 } else if (unlikely(n_frags > EF4_RX_MAX_FRAGS) || 546 unlikely(len <= (n_frags - 1) * efx->rx_dma_len) || 547 unlikely(len > n_frags * efx->rx_dma_len) || 548 unlikely(!efx->rx_scatter)) { 549 /* If this isn't an explicit discard request, either 550 * the hardware or the driver is broken. 551 */ 552 WARN_ON(!(len == 0 && rx_buf->flags & EF4_RX_PKT_DISCARD)); 553 rx_buf->flags |= EF4_RX_PKT_DISCARD; 554 } 555 556 netif_vdbg(efx, rx_status, efx->net_dev, 557 "RX queue %d received ids %x-%x len %d %s%s\n", 558 ef4_rx_queue_index(rx_queue), index, 559 (index + n_frags - 1) & rx_queue->ptr_mask, len, 560 (rx_buf->flags & EF4_RX_PKT_CSUMMED) ? " [SUMMED]" : "", 561 (rx_buf->flags & EF4_RX_PKT_DISCARD) ? " [DISCARD]" : ""); 562 563 /* Discard packet, if instructed to do so. Process the 564 * previous receive first. 565 */ 566 if (unlikely(rx_buf->flags & EF4_RX_PKT_DISCARD)) { 567 ef4_rx_flush_packet(channel); 568 ef4_discard_rx_packet(channel, rx_buf, n_frags); 569 return; 570 } 571 572 if (n_frags == 1 && !(flags & EF4_RX_PKT_PREFIX_LEN)) 573 rx_buf->len = len; 574 575 /* Release and/or sync the DMA mapping - assumes all RX buffers 576 * consumed in-order per RX queue. 577 */ 578 ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len); 579 580 /* Prefetch nice and early so data will (hopefully) be in cache by 581 * the time we look at it. 582 */ 583 prefetch(ef4_rx_buf_va(rx_buf)); 584 585 rx_buf->page_offset += efx->rx_prefix_size; 586 rx_buf->len -= efx->rx_prefix_size; 587 588 if (n_frags > 1) { 589 /* Release/sync DMA mapping for additional fragments. 590 * Fix length for last fragment. 591 */ 592 unsigned int tail_frags = n_frags - 1; 593 594 for (;;) { 595 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf); 596 if (--tail_frags == 0) 597 break; 598 ef4_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len); 599 } 600 rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len; 601 ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len); 602 } 603 604 /* All fragments have been DMA-synced, so recycle pages. */ 605 rx_buf = ef4_rx_buffer(rx_queue, index); 606 ef4_recycle_rx_pages(channel, rx_buf, n_frags); 607 608 /* Pipeline receives so that we give time for packet headers to be 609 * prefetched into cache. 610 */ 611 ef4_rx_flush_packet(channel); 612 channel->rx_pkt_n_frags = n_frags; 613 channel->rx_pkt_index = index; 614 } 615 616 static void ef4_rx_deliver(struct ef4_channel *channel, u8 *eh, 617 struct ef4_rx_buffer *rx_buf, 618 unsigned int n_frags) 619 { 620 struct sk_buff *skb; 621 u16 hdr_len = min_t(u16, rx_buf->len, EF4_SKB_HEADERS); 622 623 skb = ef4_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len); 624 if (unlikely(skb == NULL)) { 625 struct ef4_rx_queue *rx_queue; 626 627 rx_queue = ef4_channel_get_rx_queue(channel); 628 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags); 629 return; 630 } 631 skb_record_rx_queue(skb, channel->rx_queue.core_index); 632 633 /* Set the SKB flags */ 634 skb_checksum_none_assert(skb); 635 if (likely(rx_buf->flags & EF4_RX_PKT_CSUMMED)) 636 skb->ip_summed = CHECKSUM_UNNECESSARY; 637 638 if (channel->type->receive_skb) 639 if (channel->type->receive_skb(channel, skb)) 640 return; 641 642 /* Pass the packet up */ 643 netif_receive_skb(skb); 644 } 645 646 /* Handle a received packet. Second half: Touches packet payload. */ 647 void __ef4_rx_packet(struct ef4_channel *channel) 648 { 649 struct ef4_nic *efx = channel->efx; 650 struct ef4_rx_buffer *rx_buf = 651 ef4_rx_buffer(&channel->rx_queue, channel->rx_pkt_index); 652 u8 *eh = ef4_rx_buf_va(rx_buf); 653 654 /* Read length from the prefix if necessary. This already 655 * excludes the length of the prefix itself. 656 */ 657 if (rx_buf->flags & EF4_RX_PKT_PREFIX_LEN) 658 rx_buf->len = le16_to_cpup((__le16 *) 659 (eh + efx->rx_packet_len_offset)); 660 661 /* If we're in loopback test, then pass the packet directly to the 662 * loopback layer, and free the rx_buf here 663 */ 664 if (unlikely(efx->loopback_selftest)) { 665 struct ef4_rx_queue *rx_queue; 666 667 ef4_loopback_rx_packet(efx, eh, rx_buf->len); 668 rx_queue = ef4_channel_get_rx_queue(channel); 669 ef4_free_rx_buffers(rx_queue, rx_buf, 670 channel->rx_pkt_n_frags); 671 goto out; 672 } 673 674 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM))) 675 rx_buf->flags &= ~EF4_RX_PKT_CSUMMED; 676 677 if ((rx_buf->flags & EF4_RX_PKT_TCP) && !channel->type->receive_skb) 678 ef4_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh); 679 else 680 ef4_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags); 681 out: 682 channel->rx_pkt_n_frags = 0; 683 } 684 685 int ef4_probe_rx_queue(struct ef4_rx_queue *rx_queue) 686 { 687 struct ef4_nic *efx = rx_queue->efx; 688 unsigned int entries; 689 int rc; 690 691 /* Create the smallest power-of-two aligned ring */ 692 entries = max(roundup_pow_of_two(efx->rxq_entries), EF4_MIN_DMAQ_SIZE); 693 EF4_BUG_ON_PARANOID(entries > EF4_MAX_DMAQ_SIZE); 694 rx_queue->ptr_mask = entries - 1; 695 696 netif_dbg(efx, probe, efx->net_dev, 697 "creating RX queue %d size %#x mask %#x\n", 698 ef4_rx_queue_index(rx_queue), efx->rxq_entries, 699 rx_queue->ptr_mask); 700 701 /* Allocate RX buffers */ 702 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer), 703 GFP_KERNEL); 704 if (!rx_queue->buffer) 705 return -ENOMEM; 706 707 rc = ef4_nic_probe_rx(rx_queue); 708 if (rc) { 709 kfree(rx_queue->buffer); 710 rx_queue->buffer = NULL; 711 } 712 713 return rc; 714 } 715 716 static void ef4_init_rx_recycle_ring(struct ef4_nic *efx, 717 struct ef4_rx_queue *rx_queue) 718 { 719 unsigned int bufs_in_recycle_ring, page_ring_size; 720 721 /* Set the RX recycle ring size */ 722 #ifdef CONFIG_PPC64 723 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU; 724 #else 725 if (iommu_present(&pci_bus_type)) 726 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU; 727 else 728 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_NOIOMMU; 729 #endif /* CONFIG_PPC64 */ 730 731 page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring / 732 efx->rx_bufs_per_page); 733 rx_queue->page_ring = kcalloc(page_ring_size, 734 sizeof(*rx_queue->page_ring), GFP_KERNEL); 735 rx_queue->page_ptr_mask = page_ring_size - 1; 736 } 737 738 void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue) 739 { 740 struct ef4_nic *efx = rx_queue->efx; 741 unsigned int max_fill, trigger, max_trigger; 742 743 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 744 "initialising RX queue %d\n", ef4_rx_queue_index(rx_queue)); 745 746 /* Initialise ptr fields */ 747 rx_queue->added_count = 0; 748 rx_queue->notified_count = 0; 749 rx_queue->removed_count = 0; 750 rx_queue->min_fill = -1U; 751 ef4_init_rx_recycle_ring(efx, rx_queue); 752 753 rx_queue->page_remove = 0; 754 rx_queue->page_add = rx_queue->page_ptr_mask + 1; 755 rx_queue->page_recycle_count = 0; 756 rx_queue->page_recycle_failed = 0; 757 rx_queue->page_recycle_full = 0; 758 759 /* Initialise limit fields */ 760 max_fill = efx->rxq_entries - EF4_RXD_HEAD_ROOM; 761 max_trigger = 762 max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page; 763 if (rx_refill_threshold != 0) { 764 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U; 765 if (trigger > max_trigger) 766 trigger = max_trigger; 767 } else { 768 trigger = max_trigger; 769 } 770 771 rx_queue->max_fill = max_fill; 772 rx_queue->fast_fill_trigger = trigger; 773 rx_queue->refill_enabled = true; 774 775 /* Set up RX descriptor ring */ 776 ef4_nic_init_rx(rx_queue); 777 } 778 779 void ef4_fini_rx_queue(struct ef4_rx_queue *rx_queue) 780 { 781 int i; 782 struct ef4_nic *efx = rx_queue->efx; 783 struct ef4_rx_buffer *rx_buf; 784 785 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 786 "shutting down RX queue %d\n", ef4_rx_queue_index(rx_queue)); 787 788 del_timer_sync(&rx_queue->slow_fill); 789 790 /* Release RX buffers from the current read ptr to the write ptr */ 791 if (rx_queue->buffer) { 792 for (i = rx_queue->removed_count; i < rx_queue->added_count; 793 i++) { 794 unsigned index = i & rx_queue->ptr_mask; 795 rx_buf = ef4_rx_buffer(rx_queue, index); 796 ef4_fini_rx_buffer(rx_queue, rx_buf); 797 } 798 } 799 800 /* Unmap and release the pages in the recycle ring. Remove the ring. */ 801 for (i = 0; i <= rx_queue->page_ptr_mask; i++) { 802 struct page *page = rx_queue->page_ring[i]; 803 struct ef4_rx_page_state *state; 804 805 if (page == NULL) 806 continue; 807 808 state = page_address(page); 809 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, 810 PAGE_SIZE << efx->rx_buffer_order, 811 DMA_FROM_DEVICE); 812 put_page(page); 813 } 814 kfree(rx_queue->page_ring); 815 rx_queue->page_ring = NULL; 816 } 817 818 void ef4_remove_rx_queue(struct ef4_rx_queue *rx_queue) 819 { 820 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 821 "destroying RX queue %d\n", ef4_rx_queue_index(rx_queue)); 822 823 ef4_nic_remove_rx(rx_queue); 824 825 kfree(rx_queue->buffer); 826 rx_queue->buffer = NULL; 827 } 828 829 830 module_param(rx_refill_threshold, uint, 0444); 831 MODULE_PARM_DESC(rx_refill_threshold, 832 "RX descriptor ring refill threshold (%)"); 833 834 #ifdef CONFIG_RFS_ACCEL 835 836 int ef4_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb, 837 u16 rxq_index, u32 flow_id) 838 { 839 struct ef4_nic *efx = netdev_priv(net_dev); 840 struct ef4_channel *channel; 841 struct ef4_filter_spec spec; 842 struct flow_keys fk; 843 int rc; 844 845 if (flow_id == RPS_FLOW_ID_INVALID) 846 return -EINVAL; 847 848 if (!skb_flow_dissect_flow_keys(skb, &fk, 0)) 849 return -EPROTONOSUPPORT; 850 851 if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6)) 852 return -EPROTONOSUPPORT; 853 if (fk.control.flags & FLOW_DIS_IS_FRAGMENT) 854 return -EPROTONOSUPPORT; 855 856 ef4_filter_init_rx(&spec, EF4_FILTER_PRI_HINT, 857 efx->rx_scatter ? EF4_FILTER_FLAG_RX_SCATTER : 0, 858 rxq_index); 859 spec.match_flags = 860 EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_IP_PROTO | 861 EF4_FILTER_MATCH_LOC_HOST | EF4_FILTER_MATCH_LOC_PORT | 862 EF4_FILTER_MATCH_REM_HOST | EF4_FILTER_MATCH_REM_PORT; 863 spec.ether_type = fk.basic.n_proto; 864 spec.ip_proto = fk.basic.ip_proto; 865 866 if (fk.basic.n_proto == htons(ETH_P_IP)) { 867 spec.rem_host[0] = fk.addrs.v4addrs.src; 868 spec.loc_host[0] = fk.addrs.v4addrs.dst; 869 } else { 870 memcpy(spec.rem_host, &fk.addrs.v6addrs.src, sizeof(struct in6_addr)); 871 memcpy(spec.loc_host, &fk.addrs.v6addrs.dst, sizeof(struct in6_addr)); 872 } 873 874 spec.rem_port = fk.ports.src; 875 spec.loc_port = fk.ports.dst; 876 877 rc = efx->type->filter_rfs_insert(efx, &spec); 878 if (rc < 0) 879 return rc; 880 881 /* Remember this so we can check whether to expire the filter later */ 882 channel = ef4_get_channel(efx, rxq_index); 883 channel->rps_flow_id[rc] = flow_id; 884 ++channel->rfs_filters_added; 885 886 if (spec.ether_type == htons(ETH_P_IP)) 887 netif_info(efx, rx_status, efx->net_dev, 888 "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n", 889 (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP", 890 spec.rem_host, ntohs(spec.rem_port), spec.loc_host, 891 ntohs(spec.loc_port), rxq_index, flow_id, rc); 892 else 893 netif_info(efx, rx_status, efx->net_dev, 894 "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n", 895 (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP", 896 spec.rem_host, ntohs(spec.rem_port), spec.loc_host, 897 ntohs(spec.loc_port), rxq_index, flow_id, rc); 898 899 return rc; 900 } 901 902 bool __ef4_filter_rfs_expire(struct ef4_nic *efx, unsigned int quota) 903 { 904 bool (*expire_one)(struct ef4_nic *efx, u32 flow_id, unsigned int index); 905 unsigned int channel_idx, index, size; 906 u32 flow_id; 907 908 if (!spin_trylock_bh(&efx->filter_lock)) 909 return false; 910 911 expire_one = efx->type->filter_rfs_expire_one; 912 channel_idx = efx->rps_expire_channel; 913 index = efx->rps_expire_index; 914 size = efx->type->max_rx_ip_filters; 915 while (quota--) { 916 struct ef4_channel *channel = ef4_get_channel(efx, channel_idx); 917 flow_id = channel->rps_flow_id[index]; 918 919 if (flow_id != RPS_FLOW_ID_INVALID && 920 expire_one(efx, flow_id, index)) { 921 netif_info(efx, rx_status, efx->net_dev, 922 "expired filter %d [queue %u flow %u]\n", 923 index, channel_idx, flow_id); 924 channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID; 925 } 926 if (++index == size) { 927 if (++channel_idx == efx->n_channels) 928 channel_idx = 0; 929 index = 0; 930 } 931 } 932 efx->rps_expire_channel = channel_idx; 933 efx->rps_expire_index = index; 934 935 spin_unlock_bh(&efx->filter_lock); 936 return true; 937 } 938 939 #endif /* CONFIG_RFS_ACCEL */ 940 941 /** 942 * ef4_filter_is_mc_recipient - test whether spec is a multicast recipient 943 * @spec: Specification to test 944 * 945 * Return: %true if the specification is a non-drop RX filter that 946 * matches a local MAC address I/G bit value of 1 or matches a local 947 * IPv4 or IPv6 address value in the respective multicast address 948 * range. Otherwise %false. 949 */ 950 bool ef4_filter_is_mc_recipient(const struct ef4_filter_spec *spec) 951 { 952 if (!(spec->flags & EF4_FILTER_FLAG_RX) || 953 spec->dmaq_id == EF4_FILTER_RX_DMAQ_ID_DROP) 954 return false; 955 956 if (spec->match_flags & 957 (EF4_FILTER_MATCH_LOC_MAC | EF4_FILTER_MATCH_LOC_MAC_IG) && 958 is_multicast_ether_addr(spec->loc_mac)) 959 return true; 960 961 if ((spec->match_flags & 962 (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) == 963 (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) { 964 if (spec->ether_type == htons(ETH_P_IP) && 965 ipv4_is_multicast(spec->loc_host[0])) 966 return true; 967 if (spec->ether_type == htons(ETH_P_IPV6) && 968 ((const u8 *)spec->loc_host)[0] == 0xff) 969 return true; 970 } 971 972 return false; 973 } 974