1/**************************************************************************** 2 * Driver for Solarflare Solarstorm network controllers and boards 3 * Copyright 2005-2006 Fen Systems Ltd. 4 * Copyright 2005-2011 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/tcp.h> 16#include <linux/udp.h> 17#include <linux/prefetch.h> 18#include <linux/moduleparam.h> 19#include <net/ip.h> 20#include <net/checksum.h> 21#include "net_driver.h" 22#include "efx.h" 23#include "nic.h" 24#include "selftest.h" 25#include "workarounds.h" 26 27/* Number of RX descriptors pushed at once. */ 28#define EFX_RX_BATCH 8 29 30/* Maximum size of a buffer sharing a page */ 31#define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state)) 32 33/* Size of buffer allocated for skb header area. */ 34#define EFX_SKB_HEADERS 64u 35 36/* 37 * rx_alloc_method - RX buffer allocation method 38 * 39 * This driver supports two methods for allocating and using RX buffers: 40 * each RX buffer may be backed by an skb or by an order-n page. 41 * 42 * When GRO is in use then the second method has a lower overhead, 43 * since we don't have to allocate then free skbs on reassembled frames. 44 * 45 * Values: 46 * - RX_ALLOC_METHOD_AUTO = 0 47 * - RX_ALLOC_METHOD_SKB = 1 48 * - RX_ALLOC_METHOD_PAGE = 2 49 * 50 * The heuristic for %RX_ALLOC_METHOD_AUTO is a simple hysteresis count 51 * controlled by the parameters below. 52 * 53 * - Since pushing and popping descriptors are separated by the rx_queue 54 * size, so the watermarks should be ~rxd_size. 55 * - The performance win by using page-based allocation for GRO is less 56 * than the performance hit of using page-based allocation of non-GRO, 57 * so the watermarks should reflect this. 58 * 59 * Per channel we maintain a single variable, updated by each channel: 60 * 61 * rx_alloc_level += (gro_performed ? RX_ALLOC_FACTOR_GRO : 62 * RX_ALLOC_FACTOR_SKB) 63 * Per NAPI poll interval, we constrain rx_alloc_level to 0..MAX (which 64 * limits the hysteresis), and update the allocation strategy: 65 * 66 * rx_alloc_method = (rx_alloc_level > RX_ALLOC_LEVEL_GRO ? 67 * RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB) 68 */ 69static int rx_alloc_method = RX_ALLOC_METHOD_AUTO; 70 71#define RX_ALLOC_LEVEL_GRO 0x2000 72#define RX_ALLOC_LEVEL_MAX 0x3000 73#define RX_ALLOC_FACTOR_GRO 1 74#define RX_ALLOC_FACTOR_SKB (-2) 75 76/* This is the percentage fill level below which new RX descriptors 77 * will be added to the RX descriptor ring. 78 */ 79static unsigned int rx_refill_threshold = 90; 80 81/* This is the percentage fill level to which an RX queue will be refilled 82 * when the "RX refill threshold" is reached. 83 */ 84static unsigned int rx_refill_limit = 95; 85 86/* 87 * RX maximum head room required. 88 * 89 * This must be at least 1 to prevent overflow and at least 2 to allow 90 * pipelined receives. 91 */ 92#define EFX_RXD_HEAD_ROOM 2 93 94/* Offset of ethernet header within page */ 95static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx, 96 struct efx_rx_buffer *buf) 97{ 98 /* Offset is always within one page, so we don't need to consider 99 * the page order. 100 */ 101 return (((__force unsigned long) buf->dma_addr & (PAGE_SIZE - 1)) + 102 efx->type->rx_buffer_hash_size); 103} 104static inline unsigned int efx_rx_buf_size(struct efx_nic *efx) 105{ 106 return PAGE_SIZE << efx->rx_buffer_order; 107} 108 109static u8 *efx_rx_buf_eh(struct efx_nic *efx, struct efx_rx_buffer *buf) 110{ 111 if (buf->is_page) 112 return page_address(buf->u.page) + efx_rx_buf_offset(efx, buf); 113 else 114 return ((u8 *)buf->u.skb->data + 115 efx->type->rx_buffer_hash_size); 116} 117 118static inline u32 efx_rx_buf_hash(const u8 *eh) 119{ 120 /* The ethernet header is always directly after any hash. */ 121#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || NET_IP_ALIGN % 4 == 0 122 return __le32_to_cpup((const __le32 *)(eh - 4)); 123#else 124 const u8 *data = eh - 4; 125 return ((u32)data[0] | 126 (u32)data[1] << 8 | 127 (u32)data[2] << 16 | 128 (u32)data[3] << 24); 129#endif 130} 131 132/** 133 * efx_init_rx_buffers_skb - create EFX_RX_BATCH skb-based RX buffers 134 * 135 * @rx_queue: Efx RX queue 136 * 137 * This allocates EFX_RX_BATCH skbs, maps them for DMA, and populates a 138 * struct efx_rx_buffer for each one. Return a negative error code or 0 139 * on success. May fail having only inserted fewer than EFX_RX_BATCH 140 * buffers. 141 */ 142static int efx_init_rx_buffers_skb(struct efx_rx_queue *rx_queue) 143{ 144 struct efx_nic *efx = rx_queue->efx; 145 struct net_device *net_dev = efx->net_dev; 146 struct efx_rx_buffer *rx_buf; 147 struct sk_buff *skb; 148 int skb_len = efx->rx_buffer_len; 149 unsigned index, count; 150 151 for (count = 0; count < EFX_RX_BATCH; ++count) { 152 index = rx_queue->added_count & rx_queue->ptr_mask; 153 rx_buf = efx_rx_buffer(rx_queue, index); 154 155 rx_buf->u.skb = skb = netdev_alloc_skb(net_dev, skb_len); 156 if (unlikely(!skb)) 157 return -ENOMEM; 158 159 /* Adjust the SKB for padding */ 160 skb_reserve(skb, NET_IP_ALIGN); 161 rx_buf->len = skb_len - NET_IP_ALIGN; 162 rx_buf->is_page = false; 163 164 rx_buf->dma_addr = pci_map_single(efx->pci_dev, 165 skb->data, rx_buf->len, 166 PCI_DMA_FROMDEVICE); 167 if (unlikely(pci_dma_mapping_error(efx->pci_dev, 168 rx_buf->dma_addr))) { 169 dev_kfree_skb_any(skb); 170 rx_buf->u.skb = NULL; 171 return -EIO; 172 } 173 174 ++rx_queue->added_count; 175 ++rx_queue->alloc_skb_count; 176 } 177 178 return 0; 179} 180 181/** 182 * efx_init_rx_buffers_page - create EFX_RX_BATCH page-based RX buffers 183 * 184 * @rx_queue: Efx RX queue 185 * 186 * This allocates memory for EFX_RX_BATCH receive buffers, maps them for DMA, 187 * and populates struct efx_rx_buffers for each one. Return a negative error 188 * code or 0 on success. If a single page can be split between two buffers, 189 * then the page will either be inserted fully, or not at at all. 190 */ 191static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue) 192{ 193 struct efx_nic *efx = rx_queue->efx; 194 struct efx_rx_buffer *rx_buf; 195 struct page *page; 196 void *page_addr; 197 struct efx_rx_page_state *state; 198 dma_addr_t dma_addr; 199 unsigned index, count; 200 201 /* We can split a page between two buffers */ 202 BUILD_BUG_ON(EFX_RX_BATCH & 1); 203 204 for (count = 0; count < EFX_RX_BATCH; ++count) { 205 page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC, 206 efx->rx_buffer_order); 207 if (unlikely(page == NULL)) 208 return -ENOMEM; 209 dma_addr = pci_map_page(efx->pci_dev, page, 0, 210 efx_rx_buf_size(efx), 211 PCI_DMA_FROMDEVICE); 212 if (unlikely(pci_dma_mapping_error(efx->pci_dev, dma_addr))) { 213 __free_pages(page, efx->rx_buffer_order); 214 return -EIO; 215 } 216 page_addr = page_address(page); 217 state = page_addr; 218 state->refcnt = 0; 219 state->dma_addr = dma_addr; 220 221 page_addr += sizeof(struct efx_rx_page_state); 222 dma_addr += sizeof(struct efx_rx_page_state); 223 224 split: 225 index = rx_queue->added_count & rx_queue->ptr_mask; 226 rx_buf = efx_rx_buffer(rx_queue, index); 227 rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN; 228 rx_buf->u.page = page; 229 rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN; 230 rx_buf->is_page = true; 231 ++rx_queue->added_count; 232 ++rx_queue->alloc_page_count; 233 ++state->refcnt; 234 235 if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) { 236 /* Use the second half of the page */ 237 get_page(page); 238 dma_addr += (PAGE_SIZE >> 1); 239 page_addr += (PAGE_SIZE >> 1); 240 ++count; 241 goto split; 242 } 243 } 244 245 return 0; 246} 247 248static void efx_unmap_rx_buffer(struct efx_nic *efx, 249 struct efx_rx_buffer *rx_buf) 250{ 251 if (rx_buf->is_page && rx_buf->u.page) { 252 struct efx_rx_page_state *state; 253 254 state = page_address(rx_buf->u.page); 255 if (--state->refcnt == 0) { 256 pci_unmap_page(efx->pci_dev, 257 state->dma_addr, 258 efx_rx_buf_size(efx), 259 PCI_DMA_FROMDEVICE); 260 } 261 } else if (!rx_buf->is_page && rx_buf->u.skb) { 262 pci_unmap_single(efx->pci_dev, rx_buf->dma_addr, 263 rx_buf->len, PCI_DMA_FROMDEVICE); 264 } 265} 266 267static void efx_free_rx_buffer(struct efx_nic *efx, 268 struct efx_rx_buffer *rx_buf) 269{ 270 if (rx_buf->is_page && rx_buf->u.page) { 271 __free_pages(rx_buf->u.page, efx->rx_buffer_order); 272 rx_buf->u.page = NULL; 273 } else if (!rx_buf->is_page && rx_buf->u.skb) { 274 dev_kfree_skb_any(rx_buf->u.skb); 275 rx_buf->u.skb = NULL; 276 } 277} 278 279static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue, 280 struct efx_rx_buffer *rx_buf) 281{ 282 efx_unmap_rx_buffer(rx_queue->efx, rx_buf); 283 efx_free_rx_buffer(rx_queue->efx, rx_buf); 284} 285 286/* Attempt to resurrect the other receive buffer that used to share this page, 287 * which had previously been passed up to the kernel and freed. */ 288static void efx_resurrect_rx_buffer(struct efx_rx_queue *rx_queue, 289 struct efx_rx_buffer *rx_buf) 290{ 291 struct efx_rx_page_state *state = page_address(rx_buf->u.page); 292 struct efx_rx_buffer *new_buf; 293 unsigned fill_level, index; 294 295 /* +1 because efx_rx_packet() incremented removed_count. +1 because 296 * we'd like to insert an additional descriptor whilst leaving 297 * EFX_RXD_HEAD_ROOM for the non-recycle path */ 298 fill_level = (rx_queue->added_count - rx_queue->removed_count + 2); 299 if (unlikely(fill_level > rx_queue->max_fill)) { 300 /* We could place "state" on a list, and drain the list in 301 * efx_fast_push_rx_descriptors(). For now, this will do. */ 302 return; 303 } 304 305 ++state->refcnt; 306 get_page(rx_buf->u.page); 307 308 index = rx_queue->added_count & rx_queue->ptr_mask; 309 new_buf = efx_rx_buffer(rx_queue, index); 310 new_buf->dma_addr = rx_buf->dma_addr ^ (PAGE_SIZE >> 1); 311 new_buf->u.page = rx_buf->u.page; 312 new_buf->len = rx_buf->len; 313 new_buf->is_page = true; 314 ++rx_queue->added_count; 315} 316 317/* Recycle the given rx buffer directly back into the rx_queue. There is 318 * always room to add this buffer, because we've just popped a buffer. */ 319static void efx_recycle_rx_buffer(struct efx_channel *channel, 320 struct efx_rx_buffer *rx_buf) 321{ 322 struct efx_nic *efx = channel->efx; 323 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); 324 struct efx_rx_buffer *new_buf; 325 unsigned index; 326 327 if (rx_buf->is_page && efx->rx_buffer_len <= EFX_RX_HALF_PAGE && 328 page_count(rx_buf->u.page) == 1) 329 efx_resurrect_rx_buffer(rx_queue, rx_buf); 330 331 index = rx_queue->added_count & rx_queue->ptr_mask; 332 new_buf = efx_rx_buffer(rx_queue, index); 333 334 memcpy(new_buf, rx_buf, sizeof(*new_buf)); 335 rx_buf->u.page = NULL; 336 ++rx_queue->added_count; 337} 338 339/** 340 * efx_fast_push_rx_descriptors - push new RX descriptors quickly 341 * @rx_queue: RX descriptor queue 342 * This will aim to fill the RX descriptor queue up to 343 * @rx_queue->@fast_fill_limit. If there is insufficient atomic 344 * memory to do so, a slow fill will be scheduled. 345 * 346 * The caller must provide serialisation (none is used here). In practise, 347 * this means this function must run from the NAPI handler, or be called 348 * when NAPI is disabled. 349 */ 350void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue) 351{ 352 struct efx_channel *channel = efx_rx_queue_channel(rx_queue); 353 unsigned fill_level; 354 int space, rc = 0; 355 356 /* Calculate current fill level, and exit if we don't need to fill */ 357 fill_level = (rx_queue->added_count - rx_queue->removed_count); 358 EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries); 359 if (fill_level >= rx_queue->fast_fill_trigger) 360 goto out; 361 362 /* Record minimum fill level */ 363 if (unlikely(fill_level < rx_queue->min_fill)) { 364 if (fill_level) 365 rx_queue->min_fill = fill_level; 366 } 367 368 space = rx_queue->fast_fill_limit - fill_level; 369 if (space < EFX_RX_BATCH) 370 goto out; 371 372 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, 373 "RX queue %d fast-filling descriptor ring from" 374 " level %d to level %d using %s allocation\n", 375 efx_rx_queue_index(rx_queue), fill_level, 376 rx_queue->fast_fill_limit, 377 channel->rx_alloc_push_pages ? "page" : "skb"); 378 379 do { 380 if (channel->rx_alloc_push_pages) 381 rc = efx_init_rx_buffers_page(rx_queue); 382 else 383 rc = efx_init_rx_buffers_skb(rx_queue); 384 if (unlikely(rc)) { 385 /* Ensure that we don't leave the rx queue empty */ 386 if (rx_queue->added_count == rx_queue->removed_count) 387 efx_schedule_slow_fill(rx_queue); 388 goto out; 389 } 390 } while ((space -= EFX_RX_BATCH) >= EFX_RX_BATCH); 391 392 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, 393 "RX queue %d fast-filled descriptor ring " 394 "to level %d\n", efx_rx_queue_index(rx_queue), 395 rx_queue->added_count - rx_queue->removed_count); 396 397 out: 398 if (rx_queue->notified_count != rx_queue->added_count) 399 efx_nic_notify_rx_desc(rx_queue); 400} 401 402void efx_rx_slow_fill(unsigned long context) 403{ 404 struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context; 405 struct efx_channel *channel = efx_rx_queue_channel(rx_queue); 406 407 /* Post an event to cause NAPI to run and refill the queue */ 408 efx_nic_generate_fill_event(channel); 409 ++rx_queue->slow_fill_count; 410} 411 412static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue, 413 struct efx_rx_buffer *rx_buf, 414 int len, bool *discard, 415 bool *leak_packet) 416{ 417 struct efx_nic *efx = rx_queue->efx; 418 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding; 419 420 if (likely(len <= max_len)) 421 return; 422 423 /* The packet must be discarded, but this is only a fatal error 424 * if the caller indicated it was 425 */ 426 *discard = true; 427 428 if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) { 429 if (net_ratelimit()) 430 netif_err(efx, rx_err, efx->net_dev, 431 " RX queue %d seriously overlength " 432 "RX event (0x%x > 0x%x+0x%x). Leaking\n", 433 efx_rx_queue_index(rx_queue), len, max_len, 434 efx->type->rx_buffer_padding); 435 /* If this buffer was skb-allocated, then the meta 436 * data at the end of the skb will be trashed. So 437 * we have no choice but to leak the fragment. 438 */ 439 *leak_packet = !rx_buf->is_page; 440 efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY); 441 } else { 442 if (net_ratelimit()) 443 netif_err(efx, rx_err, efx->net_dev, 444 " RX queue %d overlength RX event " 445 "(0x%x > 0x%x)\n", 446 efx_rx_queue_index(rx_queue), len, max_len); 447 } 448 449 efx_rx_queue_channel(rx_queue)->n_rx_overlength++; 450} 451 452/* Pass a received packet up through the generic GRO stack 453 * 454 * Handles driverlink veto, and passes the fragment up via 455 * the appropriate GRO method 456 */ 457static void efx_rx_packet_gro(struct efx_channel *channel, 458 struct efx_rx_buffer *rx_buf, 459 const u8 *eh, bool checksummed) 460{ 461 struct napi_struct *napi = &channel->napi_str; 462 gro_result_t gro_result; 463 464 /* Pass the skb/page into the GRO engine */ 465 if (rx_buf->is_page) { 466 struct efx_nic *efx = channel->efx; 467 struct page *page = rx_buf->u.page; 468 struct sk_buff *skb; 469 470 rx_buf->u.page = NULL; 471 472 skb = napi_get_frags(napi); 473 if (!skb) { 474 put_page(page); 475 return; 476 } 477 478 if (efx->net_dev->features & NETIF_F_RXHASH) 479 skb->rxhash = efx_rx_buf_hash(eh); 480 481 skb_fill_page_desc(skb, 0, page, 482 efx_rx_buf_offset(efx, rx_buf), rx_buf->len); 483 484 skb->len = rx_buf->len; 485 skb->data_len = rx_buf->len; 486 skb->truesize += rx_buf->len; 487 skb->ip_summed = 488 checksummed ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE; 489 490 skb_record_rx_queue(skb, channel->channel); 491 492 gro_result = napi_gro_frags(napi); 493 } else { 494 struct sk_buff *skb = rx_buf->u.skb; 495 496 EFX_BUG_ON_PARANOID(!checksummed); 497 rx_buf->u.skb = NULL; 498 skb->ip_summed = CHECKSUM_UNNECESSARY; 499 500 gro_result = napi_gro_receive(napi, skb); 501 } 502 503 if (gro_result == GRO_NORMAL) { 504 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB; 505 } else if (gro_result != GRO_DROP) { 506 channel->rx_alloc_level += RX_ALLOC_FACTOR_GRO; 507 channel->irq_mod_score += 2; 508 } 509} 510 511void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index, 512 unsigned int len, bool checksummed, bool discard) 513{ 514 struct efx_nic *efx = rx_queue->efx; 515 struct efx_channel *channel = efx_rx_queue_channel(rx_queue); 516 struct efx_rx_buffer *rx_buf; 517 bool leak_packet = false; 518 519 rx_buf = efx_rx_buffer(rx_queue, index); 520 521 /* This allows the refill path to post another buffer. 522 * EFX_RXD_HEAD_ROOM ensures that the slot we are using 523 * isn't overwritten yet. 524 */ 525 rx_queue->removed_count++; 526 527 /* Validate the length encoded in the event vs the descriptor pushed */ 528 efx_rx_packet__check_len(rx_queue, rx_buf, len, 529 &discard, &leak_packet); 530 531 netif_vdbg(efx, rx_status, efx->net_dev, 532 "RX queue %d received id %x at %llx+%x %s%s\n", 533 efx_rx_queue_index(rx_queue), index, 534 (unsigned long long)rx_buf->dma_addr, len, 535 (checksummed ? " [SUMMED]" : ""), 536 (discard ? " [DISCARD]" : "")); 537 538 /* Discard packet, if instructed to do so */ 539 if (unlikely(discard)) { 540 if (unlikely(leak_packet)) 541 channel->n_skbuff_leaks++; 542 else 543 efx_recycle_rx_buffer(channel, rx_buf); 544 545 /* Don't hold off the previous receive */ 546 rx_buf = NULL; 547 goto out; 548 } 549 550 /* Release card resources - assumes all RX buffers consumed in-order 551 * per RX queue 552 */ 553 efx_unmap_rx_buffer(efx, rx_buf); 554 555 /* Prefetch nice and early so data will (hopefully) be in cache by 556 * the time we look at it. 557 */ 558 prefetch(efx_rx_buf_eh(efx, rx_buf)); 559 560 /* Pipeline receives so that we give time for packet headers to be 561 * prefetched into cache. 562 */ 563 rx_buf->len = len - efx->type->rx_buffer_hash_size; 564out: 565 if (channel->rx_pkt) 566 __efx_rx_packet(channel, 567 channel->rx_pkt, channel->rx_pkt_csummed); 568 channel->rx_pkt = rx_buf; 569 channel->rx_pkt_csummed = checksummed; 570} 571 572/* Handle a received packet. Second half: Touches packet payload. */ 573void __efx_rx_packet(struct efx_channel *channel, 574 struct efx_rx_buffer *rx_buf, bool checksummed) 575{ 576 struct efx_nic *efx = channel->efx; 577 struct sk_buff *skb; 578 u8 *eh = efx_rx_buf_eh(efx, rx_buf); 579 580 /* If we're in loopback test, then pass the packet directly to the 581 * loopback layer, and free the rx_buf here 582 */ 583 if (unlikely(efx->loopback_selftest)) { 584 efx_loopback_rx_packet(efx, eh, rx_buf->len); 585 efx_free_rx_buffer(efx, rx_buf); 586 return; 587 } 588 589 if (!rx_buf->is_page) { 590 skb = rx_buf->u.skb; 591 592 prefetch(skb_shinfo(skb)); 593 594 skb_reserve(skb, efx->type->rx_buffer_hash_size); 595 skb_put(skb, rx_buf->len); 596 597 if (efx->net_dev->features & NETIF_F_RXHASH) 598 skb->rxhash = efx_rx_buf_hash(eh); 599 600 /* Move past the ethernet header. rx_buf->data still points 601 * at the ethernet header */ 602 skb->protocol = eth_type_trans(skb, efx->net_dev); 603 604 skb_record_rx_queue(skb, channel->channel); 605 } 606 607 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM))) 608 checksummed = false; 609 610 if (likely(checksummed || rx_buf->is_page)) { 611 efx_rx_packet_gro(channel, rx_buf, eh, checksummed); 612 return; 613 } 614 615 /* We now own the SKB */ 616 skb = rx_buf->u.skb; 617 rx_buf->u.skb = NULL; 618 619 /* Set the SKB flags */ 620 skb_checksum_none_assert(skb); 621 622 /* Pass the packet up */ 623 netif_receive_skb(skb); 624 625 /* Update allocation strategy method */ 626 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB; 627} 628 629void efx_rx_strategy(struct efx_channel *channel) 630{ 631 enum efx_rx_alloc_method method = rx_alloc_method; 632 633 /* Only makes sense to use page based allocation if GRO is enabled */ 634 if (!(channel->efx->net_dev->features & NETIF_F_GRO)) { 635 method = RX_ALLOC_METHOD_SKB; 636 } else if (method == RX_ALLOC_METHOD_AUTO) { 637 /* Constrain the rx_alloc_level */ 638 if (channel->rx_alloc_level < 0) 639 channel->rx_alloc_level = 0; 640 else if (channel->rx_alloc_level > RX_ALLOC_LEVEL_MAX) 641 channel->rx_alloc_level = RX_ALLOC_LEVEL_MAX; 642 643 /* Decide on the allocation method */ 644 method = ((channel->rx_alloc_level > RX_ALLOC_LEVEL_GRO) ? 645 RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB); 646 } 647 648 /* Push the option */ 649 channel->rx_alloc_push_pages = (method == RX_ALLOC_METHOD_PAGE); 650} 651 652int efx_probe_rx_queue(struct efx_rx_queue *rx_queue) 653{ 654 struct efx_nic *efx = rx_queue->efx; 655 unsigned int entries; 656 int rc; 657 658 /* Create the smallest power-of-two aligned ring */ 659 entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE); 660 EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE); 661 rx_queue->ptr_mask = entries - 1; 662 663 netif_dbg(efx, probe, efx->net_dev, 664 "creating RX queue %d size %#x mask %#x\n", 665 efx_rx_queue_index(rx_queue), efx->rxq_entries, 666 rx_queue->ptr_mask); 667 668 /* Allocate RX buffers */ 669 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer), 670 GFP_KERNEL); 671 if (!rx_queue->buffer) 672 return -ENOMEM; 673 674 rc = efx_nic_probe_rx(rx_queue); 675 if (rc) { 676 kfree(rx_queue->buffer); 677 rx_queue->buffer = NULL; 678 } 679 return rc; 680} 681 682void efx_init_rx_queue(struct efx_rx_queue *rx_queue) 683{ 684 struct efx_nic *efx = rx_queue->efx; 685 unsigned int max_fill, trigger, limit; 686 687 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 688 "initialising RX queue %d\n", efx_rx_queue_index(rx_queue)); 689 690 /* Initialise ptr fields */ 691 rx_queue->added_count = 0; 692 rx_queue->notified_count = 0; 693 rx_queue->removed_count = 0; 694 rx_queue->min_fill = -1U; 695 696 /* Initialise limit fields */ 697 max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM; 698 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U; 699 limit = max_fill * min(rx_refill_limit, 100U) / 100U; 700 701 rx_queue->max_fill = max_fill; 702 rx_queue->fast_fill_trigger = trigger; 703 rx_queue->fast_fill_limit = limit; 704 705 /* Set up RX descriptor ring */ 706 efx_nic_init_rx(rx_queue); 707} 708 709void efx_fini_rx_queue(struct efx_rx_queue *rx_queue) 710{ 711 int i; 712 struct efx_rx_buffer *rx_buf; 713 714 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 715 "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue)); 716 717 del_timer_sync(&rx_queue->slow_fill); 718 efx_nic_fini_rx(rx_queue); 719 720 /* Release RX buffers NB start at index 0 not current HW ptr */ 721 if (rx_queue->buffer) { 722 for (i = 0; i <= rx_queue->ptr_mask; i++) { 723 rx_buf = efx_rx_buffer(rx_queue, i); 724 efx_fini_rx_buffer(rx_queue, rx_buf); 725 } 726 } 727} 728 729void efx_remove_rx_queue(struct efx_rx_queue *rx_queue) 730{ 731 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, 732 "destroying RX queue %d\n", efx_rx_queue_index(rx_queue)); 733 734 efx_nic_remove_rx(rx_queue); 735 736 kfree(rx_queue->buffer); 737 rx_queue->buffer = NULL; 738} 739 740 741module_param(rx_alloc_method, int, 0644); 742MODULE_PARM_DESC(rx_alloc_method, "Allocation method used for RX buffers"); 743 744module_param(rx_refill_threshold, uint, 0444); 745MODULE_PARM_DESC(rx_refill_threshold, 746 "RX descriptor ring fast/slow fill threshold (%)"); 747 748