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;
191 struct efx_rx_page_state *state;
193 unsigned index, count;
195 /* We can split a page between two buffers */
196 BUILD_BUG_ON(EFX_RX_BATCH & 1);
198 for (count = 0; count < EFX_RX_BATCH; ++count) {
199 page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
200 efx->rx_buffer_order);
201 if (unlikely(page == NULL))
203 dma_addr = dma_map_page(&efx->pci_dev->dev, page, 0,
204 efx_rx_buf_size(efx),
206 if (unlikely(dma_mapping_error(&efx->pci_dev->dev, dma_addr))) {
207 __free_pages(page, efx->rx_buffer_order);
210 page_addr = page_address(page);
213 state->dma_addr = dma_addr;
215 page_addr += sizeof(struct efx_rx_page_state);
216 dma_addr += sizeof(struct efx_rx_page_state);
219 index = rx_queue->added_count & rx_queue->ptr_mask;
220 rx_buf = efx_rx_buffer(rx_queue, index);
221 rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
222 rx_buf->u.page = page;
223 rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
224 rx_buf->flags = EFX_RX_BUF_PAGE;
225 ++rx_queue->added_count;
226 ++rx_queue->alloc_page_count;
229 if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) {
230 /* Use the second half of the page */
232 dma_addr += (PAGE_SIZE >> 1);
233 page_addr += (PAGE_SIZE >> 1);
242 static void efx_unmap_rx_buffer(struct efx_nic *efx,
243 struct efx_rx_buffer *rx_buf)
245 if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
246 struct efx_rx_page_state *state;
248 state = page_address(rx_buf->u.page);
249 if (--state->refcnt == 0) {
250 dma_unmap_page(&efx->pci_dev->dev,
252 efx_rx_buf_size(efx),
255 } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
256 dma_unmap_single(&efx->pci_dev->dev, rx_buf->dma_addr,
257 rx_buf->len, DMA_FROM_DEVICE);
261 static void efx_free_rx_buffer(struct efx_nic *efx,
262 struct efx_rx_buffer *rx_buf)
264 if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
265 __free_pages(rx_buf->u.page, efx->rx_buffer_order);
266 rx_buf->u.page = NULL;
267 } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
268 dev_kfree_skb_any(rx_buf->u.skb);
269 rx_buf->u.skb = NULL;
273 static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
274 struct efx_rx_buffer *rx_buf)
276 efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
277 efx_free_rx_buffer(rx_queue->efx, rx_buf);
280 /* Attempt to resurrect the other receive buffer that used to share this page,
281 * which had previously been passed up to the kernel and freed. */
282 static void efx_resurrect_rx_buffer(struct efx_rx_queue *rx_queue,
283 struct efx_rx_buffer *rx_buf)
285 struct efx_rx_page_state *state = page_address(rx_buf->u.page);
286 struct efx_rx_buffer *new_buf;
287 unsigned fill_level, index;
289 /* +1 because efx_rx_packet() incremented removed_count. +1 because
290 * we'd like to insert an additional descriptor whilst leaving
291 * EFX_RXD_HEAD_ROOM for the non-recycle path */
292 fill_level = (rx_queue->added_count - rx_queue->removed_count + 2);
293 if (unlikely(fill_level > rx_queue->max_fill)) {
294 /* We could place "state" on a list, and drain the list in
295 * efx_fast_push_rx_descriptors(). For now, this will do. */
300 get_page(rx_buf->u.page);
302 index = rx_queue->added_count & rx_queue->ptr_mask;
303 new_buf = efx_rx_buffer(rx_queue, index);
304 new_buf->dma_addr = rx_buf->dma_addr ^ (PAGE_SIZE >> 1);
305 new_buf->u.page = rx_buf->u.page;
306 new_buf->len = rx_buf->len;
307 new_buf->flags = EFX_RX_BUF_PAGE;
308 ++rx_queue->added_count;
311 /* Recycle the given rx buffer directly back into the rx_queue. There is
312 * always room to add this buffer, because we've just popped a buffer. */
313 static void efx_recycle_rx_buffer(struct efx_channel *channel,
314 struct efx_rx_buffer *rx_buf)
316 struct efx_nic *efx = channel->efx;
317 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
318 struct efx_rx_buffer *new_buf;
321 rx_buf->flags &= EFX_RX_BUF_PAGE;
323 if ((rx_buf->flags & EFX_RX_BUF_PAGE) &&
324 efx->rx_buffer_len <= EFX_RX_HALF_PAGE &&
325 page_count(rx_buf->u.page) == 1)
326 efx_resurrect_rx_buffer(rx_queue, rx_buf);
328 index = rx_queue->added_count & rx_queue->ptr_mask;
329 new_buf = efx_rx_buffer(rx_queue, index);
331 memcpy(new_buf, rx_buf, sizeof(*new_buf));
332 rx_buf->u.page = NULL;
333 ++rx_queue->added_count;
337 * efx_fast_push_rx_descriptors - push new RX descriptors quickly
338 * @rx_queue: RX descriptor queue
340 * This will aim to fill the RX descriptor queue up to
341 * @rx_queue->@max_fill. If there is insufficient atomic
342 * memory to do so, a slow fill will be scheduled.
344 * The caller must provide serialisation (none is used here). In practise,
345 * this means this function must run from the NAPI handler, or be called
346 * when NAPI is disabled.
348 void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue)
350 struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
354 /* Calculate current fill level, and exit if we don't need to fill */
355 fill_level = (rx_queue->added_count - rx_queue->removed_count);
356 EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
357 if (fill_level >= rx_queue->fast_fill_trigger)
360 /* Record minimum fill level */
361 if (unlikely(fill_level < rx_queue->min_fill)) {
363 rx_queue->min_fill = fill_level;
366 space = rx_queue->max_fill - fill_level;
367 EFX_BUG_ON_PARANOID(space < EFX_RX_BATCH);
369 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
370 "RX queue %d fast-filling descriptor ring from"
371 " level %d to level %d using %s allocation\n",
372 efx_rx_queue_index(rx_queue), fill_level,
374 channel->rx_alloc_push_pages ? "page" : "skb");
377 if (channel->rx_alloc_push_pages)
378 rc = efx_init_rx_buffers_page(rx_queue);
380 rc = efx_init_rx_buffers_skb(rx_queue);
382 /* Ensure that we don't leave the rx queue empty */
383 if (rx_queue->added_count == rx_queue->removed_count)
384 efx_schedule_slow_fill(rx_queue);
387 } while ((space -= EFX_RX_BATCH) >= EFX_RX_BATCH);
389 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
390 "RX queue %d fast-filled descriptor ring "
391 "to level %d\n", efx_rx_queue_index(rx_queue),
392 rx_queue->added_count - rx_queue->removed_count);
395 if (rx_queue->notified_count != rx_queue->added_count)
396 efx_nic_notify_rx_desc(rx_queue);
399 void efx_rx_slow_fill(unsigned long context)
401 struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context;
403 /* Post an event to cause NAPI to run and refill the queue */
404 efx_nic_generate_fill_event(rx_queue);
405 ++rx_queue->slow_fill_count;
408 static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
409 struct efx_rx_buffer *rx_buf,
410 int len, bool *leak_packet)
412 struct efx_nic *efx = rx_queue->efx;
413 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
415 if (likely(len <= max_len))
418 /* The packet must be discarded, but this is only a fatal error
419 * if the caller indicated it was
421 rx_buf->flags |= EFX_RX_PKT_DISCARD;
423 if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) {
425 netif_err(efx, rx_err, efx->net_dev,
426 " RX queue %d seriously overlength "
427 "RX event (0x%x > 0x%x+0x%x). Leaking\n",
428 efx_rx_queue_index(rx_queue), len, max_len,
429 efx->type->rx_buffer_padding);
430 /* If this buffer was skb-allocated, then the meta
431 * data at the end of the skb will be trashed. So
432 * we have no choice but to leak the fragment.
434 *leak_packet = !(rx_buf->flags & EFX_RX_BUF_PAGE);
435 efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
438 netif_err(efx, rx_err, efx->net_dev,
439 " RX queue %d overlength RX event "
441 efx_rx_queue_index(rx_queue), len, max_len);
444 efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
447 /* Pass a received packet up through GRO. GRO can handle pages
448 * regardless of checksum state and skbs with a good checksum.
450 static void efx_rx_packet_gro(struct efx_channel *channel,
451 struct efx_rx_buffer *rx_buf,
454 struct napi_struct *napi = &channel->napi_str;
455 gro_result_t gro_result;
457 if (rx_buf->flags & EFX_RX_BUF_PAGE) {
458 struct efx_nic *efx = channel->efx;
459 struct page *page = rx_buf->u.page;
462 rx_buf->u.page = NULL;
464 skb = napi_get_frags(napi);
470 if (efx->net_dev->features & NETIF_F_RXHASH)
471 skb->rxhash = efx_rx_buf_hash(eh);
473 skb_fill_page_desc(skb, 0, page,
474 efx_rx_buf_offset(efx, rx_buf), rx_buf->len);
476 skb->len = rx_buf->len;
477 skb->data_len = rx_buf->len;
478 skb->truesize += rx_buf->len;
479 skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
480 CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
482 skb_record_rx_queue(skb, channel->rx_queue.core_index);
484 gro_result = napi_gro_frags(napi);
486 struct sk_buff *skb = rx_buf->u.skb;
488 EFX_BUG_ON_PARANOID(!(rx_buf->flags & EFX_RX_PKT_CSUMMED));
489 rx_buf->u.skb = NULL;
490 skb->ip_summed = CHECKSUM_UNNECESSARY;
492 gro_result = napi_gro_receive(napi, skb);
495 if (gro_result == GRO_NORMAL) {
496 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
497 } else if (gro_result != GRO_DROP) {
498 channel->rx_alloc_level += RX_ALLOC_FACTOR_GRO;
499 channel->irq_mod_score += 2;
503 void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
504 unsigned int len, u16 flags)
506 struct efx_nic *efx = rx_queue->efx;
507 struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
508 struct efx_rx_buffer *rx_buf;
509 bool leak_packet = false;
511 rx_buf = efx_rx_buffer(rx_queue, index);
512 rx_buf->flags |= flags;
514 /* This allows the refill path to post another buffer.
515 * EFX_RXD_HEAD_ROOM ensures that the slot we are using
516 * isn't overwritten yet.
518 rx_queue->removed_count++;
520 /* Validate the length encoded in the event vs the descriptor pushed */
521 efx_rx_packet__check_len(rx_queue, rx_buf, len, &leak_packet);
523 netif_vdbg(efx, rx_status, efx->net_dev,
524 "RX queue %d received id %x at %llx+%x %s%s\n",
525 efx_rx_queue_index(rx_queue), index,
526 (unsigned long long)rx_buf->dma_addr, len,
527 (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
528 (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
530 /* Discard packet, if instructed to do so */
531 if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
532 if (unlikely(leak_packet))
533 channel->n_skbuff_leaks++;
535 efx_recycle_rx_buffer(channel, rx_buf);
537 /* Don't hold off the previous receive */
542 /* Release card resources - assumes all RX buffers consumed in-order
545 efx_unmap_rx_buffer(efx, rx_buf);
547 /* Prefetch nice and early so data will (hopefully) be in cache by
548 * the time we look at it.
550 prefetch(efx_rx_buf_eh(efx, rx_buf));
552 /* Pipeline receives so that we give time for packet headers to be
553 * prefetched into cache.
555 rx_buf->len = len - efx->type->rx_buffer_hash_size;
558 __efx_rx_packet(channel, channel->rx_pkt);
559 channel->rx_pkt = rx_buf;
562 static void efx_rx_deliver(struct efx_channel *channel,
563 struct efx_rx_buffer *rx_buf)
567 /* We now own the SKB */
569 rx_buf->u.skb = NULL;
571 /* Set the SKB flags */
572 skb_checksum_none_assert(skb);
574 /* Record the rx_queue */
575 skb_record_rx_queue(skb, channel->rx_queue.core_index);
577 /* Pass the packet up */
578 if (channel->type->receive_skb)
579 channel->type->receive_skb(channel, skb);
581 netif_receive_skb(skb);
583 /* Update allocation strategy method */
584 channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
587 /* Handle a received packet. Second half: Touches packet payload. */
588 void __efx_rx_packet(struct efx_channel *channel, struct efx_rx_buffer *rx_buf)
590 struct efx_nic *efx = channel->efx;
591 u8 *eh = efx_rx_buf_eh(efx, rx_buf);
593 /* If we're in loopback test, then pass the packet directly to the
594 * loopback layer, and free the rx_buf here
596 if (unlikely(efx->loopback_selftest)) {
597 efx_loopback_rx_packet(efx, eh, rx_buf->len);
598 efx_free_rx_buffer(efx, rx_buf);
602 if (!(rx_buf->flags & EFX_RX_BUF_PAGE)) {
603 struct sk_buff *skb = rx_buf->u.skb;
605 prefetch(skb_shinfo(skb));
607 skb_reserve(skb, efx->type->rx_buffer_hash_size);
608 skb_put(skb, rx_buf->len);
610 if (efx->net_dev->features & NETIF_F_RXHASH)
611 skb->rxhash = efx_rx_buf_hash(eh);
613 /* Move past the ethernet header. rx_buf->data still points
614 * at the ethernet header */
615 skb->protocol = eth_type_trans(skb, efx->net_dev);
617 skb_record_rx_queue(skb, channel->rx_queue.core_index);
620 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
621 rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
623 if (likely(rx_buf->flags & (EFX_RX_BUF_PAGE | EFX_RX_PKT_CSUMMED)) &&
624 !channel->type->receive_skb)
625 efx_rx_packet_gro(channel, rx_buf, eh);
627 efx_rx_deliver(channel, rx_buf);
630 void efx_rx_strategy(struct efx_channel *channel)
632 enum efx_rx_alloc_method method = rx_alloc_method;
634 if (channel->type->receive_skb) {
635 channel->rx_alloc_push_pages = false;
639 /* Only makes sense to use page based allocation if GRO is enabled */
640 if (!(channel->efx->net_dev->features & NETIF_F_GRO)) {
641 method = RX_ALLOC_METHOD_SKB;
642 } else if (method == RX_ALLOC_METHOD_AUTO) {
643 /* Constrain the rx_alloc_level */
644 if (channel->rx_alloc_level < 0)
645 channel->rx_alloc_level = 0;
646 else if (channel->rx_alloc_level > RX_ALLOC_LEVEL_MAX)
647 channel->rx_alloc_level = RX_ALLOC_LEVEL_MAX;
649 /* Decide on the allocation method */
650 method = ((channel->rx_alloc_level > RX_ALLOC_LEVEL_GRO) ?
651 RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB);
654 /* Push the option */
655 channel->rx_alloc_push_pages = (method == RX_ALLOC_METHOD_PAGE);
658 int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
660 struct efx_nic *efx = rx_queue->efx;
661 unsigned int entries;
664 /* Create the smallest power-of-two aligned ring */
665 entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
666 EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
667 rx_queue->ptr_mask = entries - 1;
669 netif_dbg(efx, probe, efx->net_dev,
670 "creating RX queue %d size %#x mask %#x\n",
671 efx_rx_queue_index(rx_queue), efx->rxq_entries,
674 /* Allocate RX buffers */
675 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
677 if (!rx_queue->buffer)
680 rc = efx_nic_probe_rx(rx_queue);
682 kfree(rx_queue->buffer);
683 rx_queue->buffer = NULL;
688 void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
690 struct efx_nic *efx = rx_queue->efx;
691 unsigned int max_fill, trigger, max_trigger;
693 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
694 "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
696 /* Initialise ptr fields */
697 rx_queue->added_count = 0;
698 rx_queue->notified_count = 0;
699 rx_queue->removed_count = 0;
700 rx_queue->min_fill = -1U;
702 /* Initialise limit fields */
703 max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
704 max_trigger = max_fill - EFX_RX_BATCH;
705 if (rx_refill_threshold != 0) {
706 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
707 if (trigger > max_trigger)
708 trigger = max_trigger;
710 trigger = max_trigger;
713 rx_queue->max_fill = max_fill;
714 rx_queue->fast_fill_trigger = trigger;
716 /* Set up RX descriptor ring */
717 rx_queue->enabled = true;
718 efx_nic_init_rx(rx_queue);
721 void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
724 struct efx_rx_buffer *rx_buf;
726 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
727 "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
729 /* A flush failure might have left rx_queue->enabled */
730 rx_queue->enabled = false;
732 del_timer_sync(&rx_queue->slow_fill);
733 efx_nic_fini_rx(rx_queue);
735 /* Release RX buffers NB start at index 0 not current HW ptr */
736 if (rx_queue->buffer) {
737 for (i = 0; i <= rx_queue->ptr_mask; i++) {
738 rx_buf = efx_rx_buffer(rx_queue, i);
739 efx_fini_rx_buffer(rx_queue, rx_buf);
744 void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
746 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
747 "destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
749 efx_nic_remove_rx(rx_queue);
751 kfree(rx_queue->buffer);
752 rx_queue->buffer = NULL;
756 module_param(rx_alloc_method, int, 0644);
757 MODULE_PARM_DESC(rx_alloc_method, "Allocation method used for RX buffers");
759 module_param(rx_refill_threshold, uint, 0444);
760 MODULE_PARM_DESC(rx_refill_threshold,
761 "RX descriptor ring refill threshold (%)");