1 /****************************************************************************
2 * Driver for Solarflare Solarstorm network controllers and boards
3 * Copyright 2005-2006 Fen Systems Ltd.
4 * Copyright 2005-2011 Solarflare Communications Inc.
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.
11 #include <linux/socket.h>
13 #include <linux/slab.h>
15 #include <linux/tcp.h>
16 #include <linux/udp.h>
17 #include <linux/prefetch.h>
18 #include <linux/moduleparam.h>
20 #include <net/checksum.h>
21 #include "net_driver.h"
25 #include "workarounds.h"
27 /* Number of RX descriptors pushed at once. */
28 #define EFX_RX_BATCH 8
30 /* Maximum size of a buffer sharing a page */
31 #define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state))
33 /* Size of buffer allocated for skb header area. */
34 #define EFX_SKB_HEADERS 64u
37 * rx_alloc_method - RX buffer allocation method
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.
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.
46 * - RX_ALLOC_METHOD_AUTO = 0
47 * - RX_ALLOC_METHOD_SKB = 1
48 * - RX_ALLOC_METHOD_PAGE = 2
50 * The heuristic for %RX_ALLOC_METHOD_AUTO is a simple hysteresis count
51 * controlled by the parameters below.
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.
59 * Per channel we maintain a single variable, updated by each channel:
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:
66 * rx_alloc_method = (rx_alloc_level > RX_ALLOC_LEVEL_GRO ?
67 * RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB)
69 static int rx_alloc_method = RX_ALLOC_METHOD_AUTO;
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)
76 /* This is the percentage fill level below which new RX descriptors
77 * will be added to the RX descriptor ring.
79 static unsigned int rx_refill_threshold;
82 * RX maximum head room required.
84 * This must be at least 1 to prevent overflow and at least 2 to allow
87 #define EFX_RXD_HEAD_ROOM 2
89 /* Offset of ethernet header within page */
90 static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx,
91 struct efx_rx_buffer *buf)
93 /* Offset is always within one page, so we don't need to consider
96 return ((unsigned int) buf->dma_addr & (PAGE_SIZE - 1)) +
97 efx->type->rx_buffer_hash_size;
99 static inline unsigned int efx_rx_buf_size(struct efx_nic *efx)
101 return PAGE_SIZE << efx->rx_buffer_order;
104 static u8 *efx_rx_buf_eh(struct efx_nic *efx, struct efx_rx_buffer *buf)
106 if (buf->flags & EFX_RX_BUF_PAGE)
107 return page_address(buf->u.page) + efx_rx_buf_offset(efx, buf);
109 return (u8 *)buf->u.skb->data + efx->type->rx_buffer_hash_size;
112 static inline u32 efx_rx_buf_hash(const u8 *eh)
114 /* The ethernet header is always directly after any hash. */
115 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || NET_IP_ALIGN % 4 == 0
116 return __le32_to_cpup((const __le32 *)(eh - 4));
118 const u8 *data = eh - 4;
119 return (u32)data[0] |
127 * efx_init_rx_buffers_skb - create EFX_RX_BATCH skb-based RX buffers
129 * @rx_queue: Efx RX queue
131 * This allocates EFX_RX_BATCH skbs, maps them for DMA, and populates a
132 * struct efx_rx_buffer for each one. Return a negative error code or 0
133 * on success. May fail having only inserted fewer than EFX_RX_BATCH
136 static int efx_init_rx_buffers_skb(struct efx_rx_queue *rx_queue)
138 struct efx_nic *efx = rx_queue->efx;
139 struct net_device *net_dev = efx->net_dev;
140 struct efx_rx_buffer *rx_buf;
142 int skb_len = efx->rx_buffer_len;
143 unsigned index, count;
145 for (count = 0; count < EFX_RX_BATCH; ++count) {
146 index = rx_queue->added_count & rx_queue->ptr_mask;
147 rx_buf = efx_rx_buffer(rx_queue, index);
149 rx_buf->u.skb = skb = netdev_alloc_skb(net_dev, skb_len);
153 /* Adjust the SKB for padding */
154 skb_reserve(skb, NET_IP_ALIGN);
155 rx_buf->len = skb_len - NET_IP_ALIGN;
158 rx_buf->dma_addr = dma_map_single(&efx->pci_dev->dev,
159 skb->data, rx_buf->len,
161 if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
162 rx_buf->dma_addr))) {
163 dev_kfree_skb_any(skb);
164 rx_buf->u.skb = NULL;
168 ++rx_queue->added_count;
169 ++rx_queue->alloc_skb_count;
176 * efx_init_rx_buffers_page - create EFX_RX_BATCH page-based RX buffers
178 * @rx_queue: Efx RX queue
180 * This allocates memory for EFX_RX_BATCH receive buffers, maps them for DMA,
181 * and populates struct efx_rx_buffers for each one. Return a negative error
182 * code or 0 on success. If a single page can be split between two buffers,
183 * then the page will either be inserted fully, or not at at all.
185 static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
187 struct efx_nic *efx = rx_queue->efx;
188 struct efx_rx_buffer *rx_buf;
190 struct efx_rx_page_state *state;
192 unsigned index, count;
194 /* We can split a page between two buffers */
195 BUILD_BUG_ON(EFX_RX_BATCH & 1);
197 for (count = 0; count < EFX_RX_BATCH; ++count) {
198 page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
199 efx->rx_buffer_order);
200 if (unlikely(page == NULL))
202 dma_addr = dma_map_page(&efx->pci_dev->dev, page, 0,
203 efx_rx_buf_size(efx),
205 if (unlikely(dma_mapping_error(&efx->pci_dev->dev, dma_addr))) {
206 __free_pages(page, efx->rx_buffer_order);
209 state = page_address(page);
211 state->dma_addr = dma_addr;
213 dma_addr += sizeof(struct efx_rx_page_state);
216 index = rx_queue->added_count & rx_queue->ptr_mask;
217 rx_buf = efx_rx_buffer(rx_queue, index);
218 rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
219 rx_buf->u.page = page;
220 rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
221 rx_buf->flags = EFX_RX_BUF_PAGE;
222 ++rx_queue->added_count;
223 ++rx_queue->alloc_page_count;
226 if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) {
227 /* Use the second half of the page */
229 dma_addr += (PAGE_SIZE >> 1);
238 static void efx_unmap_rx_buffer(struct efx_nic *efx,
239 struct efx_rx_buffer *rx_buf)
241 if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
242 struct efx_rx_page_state *state;
244 state = page_address(rx_buf->u.page);
245 if (--state->refcnt == 0) {
246 dma_unmap_page(&efx->pci_dev->dev,
248 efx_rx_buf_size(efx),
251 } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
252 dma_unmap_single(&efx->pci_dev->dev, rx_buf->dma_addr,
253 rx_buf->len, DMA_FROM_DEVICE);
257 static void efx_free_rx_buffer(struct efx_nic *efx,
258 struct efx_rx_buffer *rx_buf)
260 if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
261 __free_pages(rx_buf->u.page, efx->rx_buffer_order);
262 rx_buf->u.page = NULL;
263 } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
264 dev_kfree_skb_any(rx_buf->u.skb);
265 rx_buf->u.skb = NULL;
269 static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
270 struct efx_rx_buffer *rx_buf)
272 efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
273 efx_free_rx_buffer(rx_queue->efx, rx_buf);
276 /* Attempt to resurrect the other receive buffer that used to share this page,
277 * which had previously been passed up to the kernel and freed. */
278 static void efx_resurrect_rx_buffer(struct efx_rx_queue *rx_queue,
279 struct efx_rx_buffer *rx_buf)
281 struct efx_rx_page_state *state = page_address(rx_buf->u.page);
282 struct efx_rx_buffer *new_buf;
283 unsigned fill_level, index;
285 /* +1 because efx_rx_packet() incremented removed_count. +1 because
286 * we'd like to insert an additional descriptor whilst leaving
287 * EFX_RXD_HEAD_ROOM for the non-recycle path */
288 fill_level = (rx_queue->added_count - rx_queue->removed_count + 2);
289 if (unlikely(fill_level > rx_queue->max_fill)) {
290 /* We could place "state" on a list, and drain the list in
291 * efx_fast_push_rx_descriptors(). For now, this will do. */
296 get_page(rx_buf->u.page);
298 index = rx_queue->added_count & rx_queue->ptr_mask;
299 new_buf = efx_rx_buffer(rx_queue, index);
300 new_buf->dma_addr = rx_buf->dma_addr ^ (PAGE_SIZE >> 1);
301 new_buf->u.page = rx_buf->u.page;
302 new_buf->len = rx_buf->len;
303 new_buf->flags = EFX_RX_BUF_PAGE;
304 ++rx_queue->added_count;
307 /* Recycle the given rx buffer directly back into the rx_queue. There is
308 * always room to add this buffer, because we've just popped a buffer. */
309 static void efx_recycle_rx_buffer(struct efx_channel *channel,
310 struct efx_rx_buffer *rx_buf)
312 struct efx_nic *efx = channel->efx;
313 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
314 struct efx_rx_buffer *new_buf;
317 rx_buf->flags &= EFX_RX_BUF_PAGE;
319 if ((rx_buf->flags & EFX_RX_BUF_PAGE) &&
320 efx->rx_buffer_len <= EFX_RX_HALF_PAGE &&
321 page_count(rx_buf->u.page) == 1)
322 efx_resurrect_rx_buffer(rx_queue, rx_buf);
324 index = rx_queue->added_count & rx_queue->ptr_mask;
325 new_buf = efx_rx_buffer(rx_queue, index);
327 memcpy(new_buf, rx_buf, sizeof(*new_buf));
328 rx_buf->u.page = NULL;
329 ++rx_queue->added_count;
333 * efx_fast_push_rx_descriptors - push new RX descriptors quickly
334 * @rx_queue: RX descriptor queue
336 * This will aim to fill the RX descriptor queue up to
337 * @rx_queue->@max_fill. If there is insufficient atomic
338 * memory to do so, a slow fill will be scheduled.
340 * The caller must provide serialisation (none is used here). In practise,
341 * this means this function must run from the NAPI handler, or be called
342 * when NAPI is disabled.
344 void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue)
346 struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
350 /* Calculate current fill level, and exit if we don't need to fill */
351 fill_level = (rx_queue->added_count - rx_queue->removed_count);
352 EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
353 if (fill_level >= rx_queue->fast_fill_trigger)
356 /* Record minimum fill level */
357 if (unlikely(fill_level < rx_queue->min_fill)) {
359 rx_queue->min_fill = fill_level;
362 space = rx_queue->max_fill - fill_level;
363 EFX_BUG_ON_PARANOID(space < EFX_RX_BATCH);
365 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
366 "RX queue %d fast-filling descriptor ring from"
367 " level %d to level %d using %s allocation\n",
368 efx_rx_queue_index(rx_queue), fill_level,
370 channel->rx_alloc_push_pages ? "page" : "skb");
373 if (channel->rx_alloc_push_pages)
374 rc = efx_init_rx_buffers_page(rx_queue);
376 rc = efx_init_rx_buffers_skb(rx_queue);
378 /* Ensure that we don't leave the rx queue empty */
379 if (rx_queue->added_count == rx_queue->removed_count)
380 efx_schedule_slow_fill(rx_queue);
383 } while ((space -= EFX_RX_BATCH) >= EFX_RX_BATCH);
385 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
386 "RX queue %d fast-filled descriptor ring "
387 "to level %d\n", efx_rx_queue_index(rx_queue),
388 rx_queue->added_count - rx_queue->removed_count);
391 if (rx_queue->notified_count != rx_queue->added_count)
392 efx_nic_notify_rx_desc(rx_queue);
395 void efx_rx_slow_fill(unsigned long context)
397 struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context;
399 /* Post an event to cause NAPI to run and refill the queue */
400 efx_nic_generate_fill_event(rx_queue);
401 ++rx_queue->slow_fill_count;
404 static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
405 struct efx_rx_buffer *rx_buf,
406 int len, bool *leak_packet)
408 struct efx_nic *efx = rx_queue->efx;
409 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
411 if (likely(len <= max_len))
414 /* The packet must be discarded, but this is only a fatal error
415 * if the caller indicated it was
417 rx_buf->flags |= EFX_RX_PKT_DISCARD;
419 if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) {
421 netif_err(efx, rx_err, efx->net_dev,
422 " RX queue %d seriously overlength "
423 "RX event (0x%x > 0x%x+0x%x). Leaking\n",
424 efx_rx_queue_index(rx_queue), len, max_len,
425 efx->type->rx_buffer_padding);
426 /* If this buffer was skb-allocated, then the meta
427 * data at the end of the skb will be trashed. So
428 * we have no choice but to leak the fragment.
430 *leak_packet = !(rx_buf->flags & EFX_RX_BUF_PAGE);
431 efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
434 netif_err(efx, rx_err, efx->net_dev,
435 " RX queue %d overlength RX event "
437 efx_rx_queue_index(rx_queue), len, max_len);
440 efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
443 /* Pass a received packet up through GRO. GRO can handle pages
444 * regardless of checksum state and skbs with a good checksum.
446 static void efx_rx_packet_gro(struct efx_channel *channel,
447 struct efx_rx_buffer *rx_buf,
450 struct napi_struct *napi = &channel->napi_str;
451 gro_result_t gro_result;
453 if (rx_buf->flags & EFX_RX_BUF_PAGE) {
454 struct efx_nic *efx = channel->efx;
455 struct page *page = rx_buf->u.page;
458 rx_buf->u.page = NULL;
460 skb = napi_get_frags(napi);
466 if (efx->net_dev->features & NETIF_F_RXHASH)
467 skb->rxhash = efx_rx_buf_hash(eh);
469 skb_fill_page_desc(skb, 0, page,
470 efx_rx_buf_offset(efx, rx_buf), rx_buf->len);
472 skb->len = rx_buf->len;
473 skb->data_len = rx_buf->len;
474 skb->truesize += rx_buf->len;
475 skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
476 CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
478 skb_record_rx_queue(skb, channel->rx_queue.core_index);
480 gro_result = napi_gro_frags(napi);
482 struct sk_buff *skb = rx_buf->u.skb;
484 EFX_BUG_ON_PARANOID(!(rx_buf->flags & EFX_RX_PKT_CSUMMED));
485 rx_buf->u.skb = NULL;
486 skb->ip_summed = CHECKSUM_UNNECESSARY;
488 gro_result = napi_gro_receive(napi, skb);
491 if (gro_result == GRO_NORMAL) {
492 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
493 } else if (gro_result != GRO_DROP) {
494 channel->rx_alloc_level += RX_ALLOC_FACTOR_GRO;
495 channel->irq_mod_score += 2;
499 void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
500 unsigned int len, u16 flags)
502 struct efx_nic *efx = rx_queue->efx;
503 struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
504 struct efx_rx_buffer *rx_buf;
505 bool leak_packet = false;
507 rx_buf = efx_rx_buffer(rx_queue, index);
508 rx_buf->flags |= flags;
510 /* This allows the refill path to post another buffer.
511 * EFX_RXD_HEAD_ROOM ensures that the slot we are using
512 * isn't overwritten yet.
514 rx_queue->removed_count++;
516 /* Validate the length encoded in the event vs the descriptor pushed */
517 efx_rx_packet__check_len(rx_queue, rx_buf, len, &leak_packet);
519 netif_vdbg(efx, rx_status, efx->net_dev,
520 "RX queue %d received id %x at %llx+%x %s%s\n",
521 efx_rx_queue_index(rx_queue), index,
522 (unsigned long long)rx_buf->dma_addr, len,
523 (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
524 (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
526 /* Discard packet, if instructed to do so */
527 if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
528 if (unlikely(leak_packet))
529 channel->n_skbuff_leaks++;
531 efx_recycle_rx_buffer(channel, rx_buf);
533 /* Don't hold off the previous receive */
538 /* Release card resources - assumes all RX buffers consumed in-order
541 efx_unmap_rx_buffer(efx, rx_buf);
543 /* Prefetch nice and early so data will (hopefully) be in cache by
544 * the time we look at it.
546 prefetch(efx_rx_buf_eh(efx, rx_buf));
548 /* Pipeline receives so that we give time for packet headers to be
549 * prefetched into cache.
551 rx_buf->len = len - efx->type->rx_buffer_hash_size;
554 __efx_rx_packet(channel, channel->rx_pkt);
555 channel->rx_pkt = rx_buf;
558 static void efx_rx_deliver(struct efx_channel *channel,
559 struct efx_rx_buffer *rx_buf)
563 /* We now own the SKB */
565 rx_buf->u.skb = NULL;
567 /* Set the SKB flags */
568 skb_checksum_none_assert(skb);
570 /* Record the rx_queue */
571 skb_record_rx_queue(skb, channel->rx_queue.core_index);
573 /* Pass the packet up */
574 if (channel->type->receive_skb)
575 channel->type->receive_skb(channel, skb);
577 netif_receive_skb(skb);
579 /* Update allocation strategy method */
580 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
583 /* Handle a received packet. Second half: Touches packet payload. */
584 void __efx_rx_packet(struct efx_channel *channel, struct efx_rx_buffer *rx_buf)
586 struct efx_nic *efx = channel->efx;
587 u8 *eh = efx_rx_buf_eh(efx, rx_buf);
589 /* If we're in loopback test, then pass the packet directly to the
590 * loopback layer, and free the rx_buf here
592 if (unlikely(efx->loopback_selftest)) {
593 efx_loopback_rx_packet(efx, eh, rx_buf->len);
594 efx_free_rx_buffer(efx, rx_buf);
598 if (!(rx_buf->flags & EFX_RX_BUF_PAGE)) {
599 struct sk_buff *skb = rx_buf->u.skb;
601 prefetch(skb_shinfo(skb));
603 skb_reserve(skb, efx->type->rx_buffer_hash_size);
604 skb_put(skb, rx_buf->len);
606 if (efx->net_dev->features & NETIF_F_RXHASH)
607 skb->rxhash = efx_rx_buf_hash(eh);
609 /* Move past the ethernet header. rx_buf->data still points
610 * at the ethernet header */
611 skb->protocol = eth_type_trans(skb, efx->net_dev);
613 skb_record_rx_queue(skb, channel->rx_queue.core_index);
616 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
617 rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
619 if (likely(rx_buf->flags & (EFX_RX_BUF_PAGE | EFX_RX_PKT_CSUMMED)) &&
620 !channel->type->receive_skb)
621 efx_rx_packet_gro(channel, rx_buf, eh);
623 efx_rx_deliver(channel, rx_buf);
626 void efx_rx_strategy(struct efx_channel *channel)
628 enum efx_rx_alloc_method method = rx_alloc_method;
630 if (channel->type->receive_skb) {
631 channel->rx_alloc_push_pages = false;
635 /* Only makes sense to use page based allocation if GRO is enabled */
636 if (!(channel->efx->net_dev->features & NETIF_F_GRO)) {
637 method = RX_ALLOC_METHOD_SKB;
638 } else if (method == RX_ALLOC_METHOD_AUTO) {
639 /* Constrain the rx_alloc_level */
640 if (channel->rx_alloc_level < 0)
641 channel->rx_alloc_level = 0;
642 else if (channel->rx_alloc_level > RX_ALLOC_LEVEL_MAX)
643 channel->rx_alloc_level = RX_ALLOC_LEVEL_MAX;
645 /* Decide on the allocation method */
646 method = ((channel->rx_alloc_level > RX_ALLOC_LEVEL_GRO) ?
647 RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB);
650 /* Push the option */
651 channel->rx_alloc_push_pages = (method == RX_ALLOC_METHOD_PAGE);
654 int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
656 struct efx_nic *efx = rx_queue->efx;
657 unsigned int entries;
660 /* Create the smallest power-of-two aligned ring */
661 entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
662 EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
663 rx_queue->ptr_mask = entries - 1;
665 netif_dbg(efx, probe, efx->net_dev,
666 "creating RX queue %d size %#x mask %#x\n",
667 efx_rx_queue_index(rx_queue), efx->rxq_entries,
670 /* Allocate RX buffers */
671 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
673 if (!rx_queue->buffer)
676 rc = efx_nic_probe_rx(rx_queue);
678 kfree(rx_queue->buffer);
679 rx_queue->buffer = NULL;
684 void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
686 struct efx_nic *efx = rx_queue->efx;
687 unsigned int max_fill, trigger, max_trigger;
689 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
690 "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
692 /* Initialise ptr fields */
693 rx_queue->added_count = 0;
694 rx_queue->notified_count = 0;
695 rx_queue->removed_count = 0;
696 rx_queue->min_fill = -1U;
698 /* Initialise limit fields */
699 max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
700 max_trigger = max_fill - EFX_RX_BATCH;
701 if (rx_refill_threshold != 0) {
702 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
703 if (trigger > max_trigger)
704 trigger = max_trigger;
706 trigger = max_trigger;
709 rx_queue->max_fill = max_fill;
710 rx_queue->fast_fill_trigger = trigger;
712 /* Set up RX descriptor ring */
713 rx_queue->enabled = true;
714 efx_nic_init_rx(rx_queue);
717 void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
720 struct efx_rx_buffer *rx_buf;
722 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
723 "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
725 /* A flush failure might have left rx_queue->enabled */
726 rx_queue->enabled = false;
728 del_timer_sync(&rx_queue->slow_fill);
729 efx_nic_fini_rx(rx_queue);
731 /* Release RX buffers NB start at index 0 not current HW ptr */
732 if (rx_queue->buffer) {
733 for (i = 0; i <= rx_queue->ptr_mask; i++) {
734 rx_buf = efx_rx_buffer(rx_queue, i);
735 efx_fini_rx_buffer(rx_queue, rx_buf);
740 void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
742 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
743 "destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
745 efx_nic_remove_rx(rx_queue);
747 kfree(rx_queue->buffer);
748 rx_queue->buffer = NULL;
752 module_param(rx_alloc_method, int, 0644);
753 MODULE_PARM_DESC(rx_alloc_method, "Allocation method used for RX buffers");
755 module_param(rx_refill_threshold, uint, 0444);
756 MODULE_PARM_DESC(rx_refill_threshold,
757 "RX descriptor ring refill threshold (%)");