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v4.17
 
  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 */
 46static 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
 60static inline u8 *ef4_rx_buf_va(struct ef4_rx_buffer *buf)
 61{
 62	return page_address(buf->page) + buf->page_offset;
 63}
 64
 65static 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
 78static inline struct ef4_rx_buffer *
 79ef4_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
 87static 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
 95void 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. */
109static 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 */
152static 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 */
213static 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
227static 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 */
244static 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
276static 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. */
292static 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
304static 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 */
327void 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
379void 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
388static 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 */
425static void
426ef4_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 */
472static 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
529void 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
616static 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. */
647void __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);
681out:
682	channel->rx_pkt_n_frags = 0;
683}
684
685int 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
716static 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
738void 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
779void 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
818void 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
830module_param(rx_refill_threshold, uint, 0444);
831MODULE_PARM_DESC(rx_refill_threshold,
832		 "RX descriptor ring refill threshold (%)");
833
834#ifdef CONFIG_RFS_ACCEL
835
836int 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
902bool __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 */
950bool 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}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/****************************************************************************
  3 * Driver for Solarflare network controllers and boards
  4 * Copyright 2005-2006 Fen Systems Ltd.
  5 * Copyright 2005-2013 Solarflare Communications Inc.
 
 
 
 
  6 */
  7
  8#include <linux/socket.h>
  9#include <linux/in.h>
 10#include <linux/slab.h>
 11#include <linux/ip.h>
 12#include <linux/ipv6.h>
 13#include <linux/tcp.h>
 14#include <linux/udp.h>
 15#include <linux/prefetch.h>
 16#include <linux/moduleparam.h>
 17#include <linux/iommu.h>
 18#include <net/ip.h>
 19#include <net/checksum.h>
 20#include "net_driver.h"
 21#include "efx.h"
 22#include "filter.h"
 23#include "nic.h"
 24#include "selftest.h"
 25#include "workarounds.h"
 26
 27/* Preferred number of descriptors to fill at once */
 28#define EF4_RX_PREFERRED_BATCH 8U
 29
 30/* Number of RX buffers to recycle pages for.  When creating the RX page recycle
 31 * ring, this number is divided by the number of buffers per page to calculate
 32 * the number of pages to store in the RX page recycle ring.
 33 */
 34#define EF4_RECYCLE_RING_SIZE_IOMMU 4096
 35#define EF4_RECYCLE_RING_SIZE_NOIOMMU (2 * EF4_RX_PREFERRED_BATCH)
 36
 37/* Size of buffer allocated for skb header area. */
 38#define EF4_SKB_HEADERS  128u
 39
 40/* This is the percentage fill level below which new RX descriptors
 41 * will be added to the RX descriptor ring.
 42 */
 43static unsigned int rx_refill_threshold;
 44
 45/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
 46#define EF4_RX_MAX_FRAGS DIV_ROUND_UP(EF4_MAX_FRAME_LEN(EF4_MAX_MTU), \
 47				      EF4_RX_USR_BUF_SIZE)
 48
 49/*
 50 * RX maximum head room required.
 51 *
 52 * This must be at least 1 to prevent overflow, plus one packet-worth
 53 * to allow pipelined receives.
 54 */
 55#define EF4_RXD_HEAD_ROOM (1 + EF4_RX_MAX_FRAGS)
 56
 57static inline u8 *ef4_rx_buf_va(struct ef4_rx_buffer *buf)
 58{
 59	return page_address(buf->page) + buf->page_offset;
 60}
 61
 62static inline u32 ef4_rx_buf_hash(struct ef4_nic *efx, const u8 *eh)
 63{
 64#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
 65	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_hash_offset));
 66#else
 67	const u8 *data = eh + efx->rx_packet_hash_offset;
 68	return (u32)data[0]	  |
 69	       (u32)data[1] << 8  |
 70	       (u32)data[2] << 16 |
 71	       (u32)data[3] << 24;
 72#endif
 73}
 74
 75static inline struct ef4_rx_buffer *
 76ef4_rx_buf_next(struct ef4_rx_queue *rx_queue, struct ef4_rx_buffer *rx_buf)
 77{
 78	if (unlikely(rx_buf == ef4_rx_buffer(rx_queue, rx_queue->ptr_mask)))
 79		return ef4_rx_buffer(rx_queue, 0);
 80	else
 81		return rx_buf + 1;
 82}
 83
 84static inline void ef4_sync_rx_buffer(struct ef4_nic *efx,
 85				      struct ef4_rx_buffer *rx_buf,
 86				      unsigned int len)
 87{
 88	dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len,
 89				DMA_FROM_DEVICE);
 90}
 91
 92void ef4_rx_config_page_split(struct ef4_nic *efx)
 93{
 94	efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align,
 95				      EF4_RX_BUF_ALIGNMENT);
 96	efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
 97		((PAGE_SIZE - sizeof(struct ef4_rx_page_state)) /
 98		 efx->rx_page_buf_step);
 99	efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
100		efx->rx_bufs_per_page;
101	efx->rx_pages_per_batch = DIV_ROUND_UP(EF4_RX_PREFERRED_BATCH,
102					       efx->rx_bufs_per_page);
103}
104
105/* Check the RX page recycle ring for a page that can be reused. */
106static struct page *ef4_reuse_page(struct ef4_rx_queue *rx_queue)
107{
108	struct ef4_nic *efx = rx_queue->efx;
109	struct page *page;
110	struct ef4_rx_page_state *state;
111	unsigned index;
112
113	index = rx_queue->page_remove & rx_queue->page_ptr_mask;
114	page = rx_queue->page_ring[index];
115	if (page == NULL)
116		return NULL;
117
118	rx_queue->page_ring[index] = NULL;
119	/* page_remove cannot exceed page_add. */
120	if (rx_queue->page_remove != rx_queue->page_add)
121		++rx_queue->page_remove;
122
123	/* If page_count is 1 then we hold the only reference to this page. */
124	if (page_count(page) == 1) {
125		++rx_queue->page_recycle_count;
126		return page;
127	} else {
128		state = page_address(page);
129		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
130			       PAGE_SIZE << efx->rx_buffer_order,
131			       DMA_FROM_DEVICE);
132		put_page(page);
133		++rx_queue->page_recycle_failed;
134	}
135
136	return NULL;
137}
138
139/**
140 * ef4_init_rx_buffers - create EF4_RX_BATCH page-based RX buffers
141 *
142 * @rx_queue:		Efx RX queue
143 * @atomic:		control memory allocation flags
144 *
145 * This allocates a batch of pages, maps them for DMA, and populates
146 * struct ef4_rx_buffers for each one. Return a negative error code or
147 * 0 on success. If a single page can be used for multiple buffers,
148 * then the page will either be inserted fully, or not at all.
149 */
150static int ef4_init_rx_buffers(struct ef4_rx_queue *rx_queue, bool atomic)
151{
152	struct ef4_nic *efx = rx_queue->efx;
153	struct ef4_rx_buffer *rx_buf;
154	struct page *page;
155	unsigned int page_offset;
156	struct ef4_rx_page_state *state;
157	dma_addr_t dma_addr;
158	unsigned index, count;
159
160	count = 0;
161	do {
162		page = ef4_reuse_page(rx_queue);
163		if (page == NULL) {
164			page = alloc_pages(__GFP_COMP |
165					   (atomic ? GFP_ATOMIC : GFP_KERNEL),
166					   efx->rx_buffer_order);
167			if (unlikely(page == NULL))
168				return -ENOMEM;
169			dma_addr =
170				dma_map_page(&efx->pci_dev->dev, page, 0,
171					     PAGE_SIZE << efx->rx_buffer_order,
172					     DMA_FROM_DEVICE);
173			if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
174						       dma_addr))) {
175				__free_pages(page, efx->rx_buffer_order);
176				return -EIO;
177			}
178			state = page_address(page);
179			state->dma_addr = dma_addr;
180		} else {
181			state = page_address(page);
182			dma_addr = state->dma_addr;
183		}
184
185		dma_addr += sizeof(struct ef4_rx_page_state);
186		page_offset = sizeof(struct ef4_rx_page_state);
187
188		do {
189			index = rx_queue->added_count & rx_queue->ptr_mask;
190			rx_buf = ef4_rx_buffer(rx_queue, index);
191			rx_buf->dma_addr = dma_addr + efx->rx_ip_align;
192			rx_buf->page = page;
193			rx_buf->page_offset = page_offset + efx->rx_ip_align;
194			rx_buf->len = efx->rx_dma_len;
195			rx_buf->flags = 0;
196			++rx_queue->added_count;
197			get_page(page);
198			dma_addr += efx->rx_page_buf_step;
199			page_offset += efx->rx_page_buf_step;
200		} while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE);
201
202		rx_buf->flags = EF4_RX_BUF_LAST_IN_PAGE;
203	} while (++count < efx->rx_pages_per_batch);
204
205	return 0;
206}
207
208/* Unmap a DMA-mapped page.  This function is only called for the final RX
209 * buffer in a page.
210 */
211static void ef4_unmap_rx_buffer(struct ef4_nic *efx,
212				struct ef4_rx_buffer *rx_buf)
213{
214	struct page *page = rx_buf->page;
215
216	if (page) {
217		struct ef4_rx_page_state *state = page_address(page);
218		dma_unmap_page(&efx->pci_dev->dev,
219			       state->dma_addr,
220			       PAGE_SIZE << efx->rx_buffer_order,
221			       DMA_FROM_DEVICE);
222	}
223}
224
225static void ef4_free_rx_buffers(struct ef4_rx_queue *rx_queue,
226				struct ef4_rx_buffer *rx_buf,
227				unsigned int num_bufs)
228{
229	do {
230		if (rx_buf->page) {
231			put_page(rx_buf->page);
232			rx_buf->page = NULL;
233		}
234		rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
235	} while (--num_bufs);
236}
237
238/* Attempt to recycle the page if there is an RX recycle ring; the page can
239 * only be added if this is the final RX buffer, to prevent pages being used in
240 * the descriptor ring and appearing in the recycle ring simultaneously.
241 */
242static void ef4_recycle_rx_page(struct ef4_channel *channel,
243				struct ef4_rx_buffer *rx_buf)
244{
245	struct page *page = rx_buf->page;
246	struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
247	struct ef4_nic *efx = rx_queue->efx;
248	unsigned index;
249
250	/* Only recycle the page after processing the final buffer. */
251	if (!(rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE))
252		return;
253
254	index = rx_queue->page_add & rx_queue->page_ptr_mask;
255	if (rx_queue->page_ring[index] == NULL) {
256		unsigned read_index = rx_queue->page_remove &
257			rx_queue->page_ptr_mask;
258
259		/* The next slot in the recycle ring is available, but
260		 * increment page_remove if the read pointer currently
261		 * points here.
262		 */
263		if (read_index == index)
264			++rx_queue->page_remove;
265		rx_queue->page_ring[index] = page;
266		++rx_queue->page_add;
267		return;
268	}
269	++rx_queue->page_recycle_full;
270	ef4_unmap_rx_buffer(efx, rx_buf);
271	put_page(rx_buf->page);
272}
273
274static void ef4_fini_rx_buffer(struct ef4_rx_queue *rx_queue,
275			       struct ef4_rx_buffer *rx_buf)
276{
277	/* Release the page reference we hold for the buffer. */
278	if (rx_buf->page)
279		put_page(rx_buf->page);
280
281	/* If this is the last buffer in a page, unmap and free it. */
282	if (rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE) {
283		ef4_unmap_rx_buffer(rx_queue->efx, rx_buf);
284		ef4_free_rx_buffers(rx_queue, rx_buf, 1);
285	}
286	rx_buf->page = NULL;
287}
288
289/* Recycle the pages that are used by buffers that have just been received. */
290static void ef4_recycle_rx_pages(struct ef4_channel *channel,
291				 struct ef4_rx_buffer *rx_buf,
292				 unsigned int n_frags)
293{
294	struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
295
296	do {
297		ef4_recycle_rx_page(channel, rx_buf);
298		rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
299	} while (--n_frags);
300}
301
302static void ef4_discard_rx_packet(struct ef4_channel *channel,
303				  struct ef4_rx_buffer *rx_buf,
304				  unsigned int n_frags)
305{
306	struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
307
308	ef4_recycle_rx_pages(channel, rx_buf, n_frags);
309
310	ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
311}
312
313/**
314 * ef4_fast_push_rx_descriptors - push new RX descriptors quickly
315 * @rx_queue:		RX descriptor queue
316 *
317 * This will aim to fill the RX descriptor queue up to
318 * @rx_queue->@max_fill. If there is insufficient atomic
319 * memory to do so, a slow fill will be scheduled.
320 * @atomic: control memory allocation flags
321 *
322 * The caller must provide serialisation (none is used here). In practise,
323 * this means this function must run from the NAPI handler, or be called
324 * when NAPI is disabled.
325 */
326void ef4_fast_push_rx_descriptors(struct ef4_rx_queue *rx_queue, bool atomic)
327{
328	struct ef4_nic *efx = rx_queue->efx;
329	unsigned int fill_level, batch_size;
330	int space, rc = 0;
331
332	if (!rx_queue->refill_enabled)
333		return;
334
335	/* Calculate current fill level, and exit if we don't need to fill */
336	fill_level = (rx_queue->added_count - rx_queue->removed_count);
337	EF4_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
338	if (fill_level >= rx_queue->fast_fill_trigger)
339		goto out;
340
341	/* Record minimum fill level */
342	if (unlikely(fill_level < rx_queue->min_fill)) {
343		if (fill_level)
344			rx_queue->min_fill = fill_level;
345	}
346
347	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
348	space = rx_queue->max_fill - fill_level;
349	EF4_BUG_ON_PARANOID(space < batch_size);
350
351	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
352		   "RX queue %d fast-filling descriptor ring from"
353		   " level %d to level %d\n",
354		   ef4_rx_queue_index(rx_queue), fill_level,
355		   rx_queue->max_fill);
356
357
358	do {
359		rc = ef4_init_rx_buffers(rx_queue, atomic);
360		if (unlikely(rc)) {
361			/* Ensure that we don't leave the rx queue empty */
362			if (rx_queue->added_count == rx_queue->removed_count)
363				ef4_schedule_slow_fill(rx_queue);
364			goto out;
365		}
366	} while ((space -= batch_size) >= batch_size);
367
368	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
369		   "RX queue %d fast-filled descriptor ring "
370		   "to level %d\n", ef4_rx_queue_index(rx_queue),
371		   rx_queue->added_count - rx_queue->removed_count);
372
373 out:
374	if (rx_queue->notified_count != rx_queue->added_count)
375		ef4_nic_notify_rx_desc(rx_queue);
376}
377
378void ef4_rx_slow_fill(struct timer_list *t)
379{
380	struct ef4_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);
381
382	/* Post an event to cause NAPI to run and refill the queue */
383	ef4_nic_generate_fill_event(rx_queue);
384	++rx_queue->slow_fill_count;
385}
386
387static void ef4_rx_packet__check_len(struct ef4_rx_queue *rx_queue,
388				     struct ef4_rx_buffer *rx_buf,
389				     int len)
390{
391	struct ef4_nic *efx = rx_queue->efx;
392	unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
393
394	if (likely(len <= max_len))
395		return;
396
397	/* The packet must be discarded, but this is only a fatal error
398	 * if the caller indicated it was
399	 */
400	rx_buf->flags |= EF4_RX_PKT_DISCARD;
401
402	if ((len > rx_buf->len) && EF4_WORKAROUND_8071(efx)) {
403		if (net_ratelimit())
404			netif_err(efx, rx_err, efx->net_dev,
405				  " RX queue %d seriously overlength "
406				  "RX event (0x%x > 0x%x+0x%x). Leaking\n",
407				  ef4_rx_queue_index(rx_queue), len, max_len,
408				  efx->type->rx_buffer_padding);
409		ef4_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
410	} else {
411		if (net_ratelimit())
412			netif_err(efx, rx_err, efx->net_dev,
413				  " RX queue %d overlength RX event "
414				  "(0x%x > 0x%x)\n",
415				  ef4_rx_queue_index(rx_queue), len, max_len);
416	}
417
418	ef4_rx_queue_channel(rx_queue)->n_rx_overlength++;
419}
420
421/* Pass a received packet up through GRO.  GRO can handle pages
422 * regardless of checksum state and skbs with a good checksum.
423 */
424static void
425ef4_rx_packet_gro(struct ef4_channel *channel, struct ef4_rx_buffer *rx_buf,
426		  unsigned int n_frags, u8 *eh)
427{
428	struct napi_struct *napi = &channel->napi_str;
 
429	struct ef4_nic *efx = channel->efx;
430	struct sk_buff *skb;
431
432	skb = napi_get_frags(napi);
433	if (unlikely(!skb)) {
434		struct ef4_rx_queue *rx_queue;
435
436		rx_queue = ef4_channel_get_rx_queue(channel);
437		ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
438		return;
439	}
440
441	if (efx->net_dev->features & NETIF_F_RXHASH)
442		skb_set_hash(skb, ef4_rx_buf_hash(efx, eh),
443			     PKT_HASH_TYPE_L3);
444	skb->ip_summed = ((rx_buf->flags & EF4_RX_PKT_CSUMMED) ?
445			  CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
446
447	for (;;) {
448		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
449				   rx_buf->page, rx_buf->page_offset,
450				   rx_buf->len);
451		rx_buf->page = NULL;
452		skb->len += rx_buf->len;
453		if (skb_shinfo(skb)->nr_frags == n_frags)
454			break;
455
456		rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
457	}
458
459	skb->data_len = skb->len;
460	skb->truesize += n_frags * efx->rx_buffer_truesize;
461
462	skb_record_rx_queue(skb, channel->rx_queue.core_index);
463
464	napi_gro_frags(napi);
 
 
465}
466
467/* Allocate and construct an SKB around page fragments */
468static struct sk_buff *ef4_rx_mk_skb(struct ef4_channel *channel,
469				     struct ef4_rx_buffer *rx_buf,
470				     unsigned int n_frags,
471				     u8 *eh, int hdr_len)
472{
473	struct ef4_nic *efx = channel->efx;
474	struct sk_buff *skb;
475
476	/* Allocate an SKB to store the headers */
477	skb = netdev_alloc_skb(efx->net_dev,
478			       efx->rx_ip_align + efx->rx_prefix_size +
479			       hdr_len);
480	if (unlikely(skb == NULL)) {
481		atomic_inc(&efx->n_rx_noskb_drops);
482		return NULL;
483	}
484
485	EF4_BUG_ON_PARANOID(rx_buf->len < hdr_len);
486
487	memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
488	       efx->rx_prefix_size + hdr_len);
489	skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
490	__skb_put(skb, hdr_len);
491
492	/* Append the remaining page(s) onto the frag list */
493	if (rx_buf->len > hdr_len) {
494		rx_buf->page_offset += hdr_len;
495		rx_buf->len -= hdr_len;
496
497		for (;;) {
498			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
499					   rx_buf->page, rx_buf->page_offset,
500					   rx_buf->len);
501			rx_buf->page = NULL;
502			skb->len += rx_buf->len;
503			skb->data_len += rx_buf->len;
504			if (skb_shinfo(skb)->nr_frags == n_frags)
505				break;
506
507			rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
508		}
509	} else {
510		__free_pages(rx_buf->page, efx->rx_buffer_order);
511		rx_buf->page = NULL;
512		n_frags = 0;
513	}
514
515	skb->truesize += n_frags * efx->rx_buffer_truesize;
516
517	/* Move past the ethernet header */
518	skb->protocol = eth_type_trans(skb, efx->net_dev);
519
520	skb_mark_napi_id(skb, &channel->napi_str);
521
522	return skb;
523}
524
525void ef4_rx_packet(struct ef4_rx_queue *rx_queue, unsigned int index,
526		   unsigned int n_frags, unsigned int len, u16 flags)
527{
528	struct ef4_nic *efx = rx_queue->efx;
529	struct ef4_channel *channel = ef4_rx_queue_channel(rx_queue);
530	struct ef4_rx_buffer *rx_buf;
531
532	rx_queue->rx_packets++;
533
534	rx_buf = ef4_rx_buffer(rx_queue, index);
535	rx_buf->flags |= flags;
536
537	/* Validate the number of fragments and completed length */
538	if (n_frags == 1) {
539		if (!(flags & EF4_RX_PKT_PREFIX_LEN))
540			ef4_rx_packet__check_len(rx_queue, rx_buf, len);
541	} else if (unlikely(n_frags > EF4_RX_MAX_FRAGS) ||
542		   unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
543		   unlikely(len > n_frags * efx->rx_dma_len) ||
544		   unlikely(!efx->rx_scatter)) {
545		/* If this isn't an explicit discard request, either
546		 * the hardware or the driver is broken.
547		 */
548		WARN_ON(!(len == 0 && rx_buf->flags & EF4_RX_PKT_DISCARD));
549		rx_buf->flags |= EF4_RX_PKT_DISCARD;
550	}
551
552	netif_vdbg(efx, rx_status, efx->net_dev,
553		   "RX queue %d received ids %x-%x len %d %s%s\n",
554		   ef4_rx_queue_index(rx_queue), index,
555		   (index + n_frags - 1) & rx_queue->ptr_mask, len,
556		   (rx_buf->flags & EF4_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
557		   (rx_buf->flags & EF4_RX_PKT_DISCARD) ? " [DISCARD]" : "");
558
559	/* Discard packet, if instructed to do so.  Process the
560	 * previous receive first.
561	 */
562	if (unlikely(rx_buf->flags & EF4_RX_PKT_DISCARD)) {
563		ef4_rx_flush_packet(channel);
564		ef4_discard_rx_packet(channel, rx_buf, n_frags);
565		return;
566	}
567
568	if (n_frags == 1 && !(flags & EF4_RX_PKT_PREFIX_LEN))
569		rx_buf->len = len;
570
571	/* Release and/or sync the DMA mapping - assumes all RX buffers
572	 * consumed in-order per RX queue.
573	 */
574	ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
575
576	/* Prefetch nice and early so data will (hopefully) be in cache by
577	 * the time we look at it.
578	 */
579	prefetch(ef4_rx_buf_va(rx_buf));
580
581	rx_buf->page_offset += efx->rx_prefix_size;
582	rx_buf->len -= efx->rx_prefix_size;
583
584	if (n_frags > 1) {
585		/* Release/sync DMA mapping for additional fragments.
586		 * Fix length for last fragment.
587		 */
588		unsigned int tail_frags = n_frags - 1;
589
590		for (;;) {
591			rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
592			if (--tail_frags == 0)
593				break;
594			ef4_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
595		}
596		rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
597		ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
598	}
599
600	/* All fragments have been DMA-synced, so recycle pages. */
601	rx_buf = ef4_rx_buffer(rx_queue, index);
602	ef4_recycle_rx_pages(channel, rx_buf, n_frags);
603
604	/* Pipeline receives so that we give time for packet headers to be
605	 * prefetched into cache.
606	 */
607	ef4_rx_flush_packet(channel);
608	channel->rx_pkt_n_frags = n_frags;
609	channel->rx_pkt_index = index;
610}
611
612static void ef4_rx_deliver(struct ef4_channel *channel, u8 *eh,
613			   struct ef4_rx_buffer *rx_buf,
614			   unsigned int n_frags)
615{
616	struct sk_buff *skb;
617	u16 hdr_len = min_t(u16, rx_buf->len, EF4_SKB_HEADERS);
618
619	skb = ef4_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
620	if (unlikely(skb == NULL)) {
621		struct ef4_rx_queue *rx_queue;
622
623		rx_queue = ef4_channel_get_rx_queue(channel);
624		ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
625		return;
626	}
627	skb_record_rx_queue(skb, channel->rx_queue.core_index);
628
629	/* Set the SKB flags */
630	skb_checksum_none_assert(skb);
631	if (likely(rx_buf->flags & EF4_RX_PKT_CSUMMED))
632		skb->ip_summed = CHECKSUM_UNNECESSARY;
633
634	if (channel->type->receive_skb)
635		if (channel->type->receive_skb(channel, skb))
636			return;
637
638	/* Pass the packet up */
639	netif_receive_skb(skb);
640}
641
642/* Handle a received packet.  Second half: Touches packet payload. */
643void __ef4_rx_packet(struct ef4_channel *channel)
644{
645	struct ef4_nic *efx = channel->efx;
646	struct ef4_rx_buffer *rx_buf =
647		ef4_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
648	u8 *eh = ef4_rx_buf_va(rx_buf);
649
650	/* Read length from the prefix if necessary.  This already
651	 * excludes the length of the prefix itself.
652	 */
653	if (rx_buf->flags & EF4_RX_PKT_PREFIX_LEN)
654		rx_buf->len = le16_to_cpup((__le16 *)
655					   (eh + efx->rx_packet_len_offset));
656
657	/* If we're in loopback test, then pass the packet directly to the
658	 * loopback layer, and free the rx_buf here
659	 */
660	if (unlikely(efx->loopback_selftest)) {
661		struct ef4_rx_queue *rx_queue;
662
663		ef4_loopback_rx_packet(efx, eh, rx_buf->len);
664		rx_queue = ef4_channel_get_rx_queue(channel);
665		ef4_free_rx_buffers(rx_queue, rx_buf,
666				    channel->rx_pkt_n_frags);
667		goto out;
668	}
669
670	if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
671		rx_buf->flags &= ~EF4_RX_PKT_CSUMMED;
672
673	if ((rx_buf->flags & EF4_RX_PKT_TCP) && !channel->type->receive_skb)
674		ef4_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
675	else
676		ef4_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
677out:
678	channel->rx_pkt_n_frags = 0;
679}
680
681int ef4_probe_rx_queue(struct ef4_rx_queue *rx_queue)
682{
683	struct ef4_nic *efx = rx_queue->efx;
684	unsigned int entries;
685	int rc;
686
687	/* Create the smallest power-of-two aligned ring */
688	entries = max(roundup_pow_of_two(efx->rxq_entries), EF4_MIN_DMAQ_SIZE);
689	EF4_BUG_ON_PARANOID(entries > EF4_MAX_DMAQ_SIZE);
690	rx_queue->ptr_mask = entries - 1;
691
692	netif_dbg(efx, probe, efx->net_dev,
693		  "creating RX queue %d size %#x mask %#x\n",
694		  ef4_rx_queue_index(rx_queue), efx->rxq_entries,
695		  rx_queue->ptr_mask);
696
697	/* Allocate RX buffers */
698	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
699				   GFP_KERNEL);
700	if (!rx_queue->buffer)
701		return -ENOMEM;
702
703	rc = ef4_nic_probe_rx(rx_queue);
704	if (rc) {
705		kfree(rx_queue->buffer);
706		rx_queue->buffer = NULL;
707	}
708
709	return rc;
710}
711
712static void ef4_init_rx_recycle_ring(struct ef4_nic *efx,
713				     struct ef4_rx_queue *rx_queue)
714{
715	unsigned int bufs_in_recycle_ring, page_ring_size;
716
717	/* Set the RX recycle ring size */
718#ifdef CONFIG_PPC64
719	bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
720#else
721	if (iommu_present(&pci_bus_type))
722		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
723	else
724		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_NOIOMMU;
725#endif /* CONFIG_PPC64 */
726
727	page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /
728					    efx->rx_bufs_per_page);
729	rx_queue->page_ring = kcalloc(page_ring_size,
730				      sizeof(*rx_queue->page_ring), GFP_KERNEL);
731	rx_queue->page_ptr_mask = page_ring_size - 1;
732}
733
734void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue)
735{
736	struct ef4_nic *efx = rx_queue->efx;
737	unsigned int max_fill, trigger, max_trigger;
738
739	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
740		  "initialising RX queue %d\n", ef4_rx_queue_index(rx_queue));
741
742	/* Initialise ptr fields */
743	rx_queue->added_count = 0;
744	rx_queue->notified_count = 0;
745	rx_queue->removed_count = 0;
746	rx_queue->min_fill = -1U;
747	ef4_init_rx_recycle_ring(efx, rx_queue);
748
749	rx_queue->page_remove = 0;
750	rx_queue->page_add = rx_queue->page_ptr_mask + 1;
751	rx_queue->page_recycle_count = 0;
752	rx_queue->page_recycle_failed = 0;
753	rx_queue->page_recycle_full = 0;
754
755	/* Initialise limit fields */
756	max_fill = efx->rxq_entries - EF4_RXD_HEAD_ROOM;
757	max_trigger =
758		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
759	if (rx_refill_threshold != 0) {
760		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
761		if (trigger > max_trigger)
762			trigger = max_trigger;
763	} else {
764		trigger = max_trigger;
765	}
766
767	rx_queue->max_fill = max_fill;
768	rx_queue->fast_fill_trigger = trigger;
769	rx_queue->refill_enabled = true;
770
771	/* Set up RX descriptor ring */
772	ef4_nic_init_rx(rx_queue);
773}
774
775void ef4_fini_rx_queue(struct ef4_rx_queue *rx_queue)
776{
777	int i;
778	struct ef4_nic *efx = rx_queue->efx;
779	struct ef4_rx_buffer *rx_buf;
780
781	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
782		  "shutting down RX queue %d\n", ef4_rx_queue_index(rx_queue));
783
784	del_timer_sync(&rx_queue->slow_fill);
785
786	/* Release RX buffers from the current read ptr to the write ptr */
787	if (rx_queue->buffer) {
788		for (i = rx_queue->removed_count; i < rx_queue->added_count;
789		     i++) {
790			unsigned index = i & rx_queue->ptr_mask;
791			rx_buf = ef4_rx_buffer(rx_queue, index);
792			ef4_fini_rx_buffer(rx_queue, rx_buf);
793		}
794	}
795
796	/* Unmap and release the pages in the recycle ring. Remove the ring. */
797	for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
798		struct page *page = rx_queue->page_ring[i];
799		struct ef4_rx_page_state *state;
800
801		if (page == NULL)
802			continue;
803
804		state = page_address(page);
805		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
806			       PAGE_SIZE << efx->rx_buffer_order,
807			       DMA_FROM_DEVICE);
808		put_page(page);
809	}
810	kfree(rx_queue->page_ring);
811	rx_queue->page_ring = NULL;
812}
813
814void ef4_remove_rx_queue(struct ef4_rx_queue *rx_queue)
815{
816	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
817		  "destroying RX queue %d\n", ef4_rx_queue_index(rx_queue));
818
819	ef4_nic_remove_rx(rx_queue);
820
821	kfree(rx_queue->buffer);
822	rx_queue->buffer = NULL;
823}
824
825
826module_param(rx_refill_threshold, uint, 0444);
827MODULE_PARM_DESC(rx_refill_threshold,
828		 "RX descriptor ring refill threshold (%)");
829
830#ifdef CONFIG_RFS_ACCEL
831
832int ef4_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
833		   u16 rxq_index, u32 flow_id)
834{
835	struct ef4_nic *efx = netdev_priv(net_dev);
836	struct ef4_channel *channel;
837	struct ef4_filter_spec spec;
838	struct flow_keys fk;
839	int rc;
840
841	if (flow_id == RPS_FLOW_ID_INVALID)
842		return -EINVAL;
843
844	if (!skb_flow_dissect_flow_keys(skb, &fk, 0))
845		return -EPROTONOSUPPORT;
846
847	if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6))
848		return -EPROTONOSUPPORT;
849	if (fk.control.flags & FLOW_DIS_IS_FRAGMENT)
850		return -EPROTONOSUPPORT;
851
852	ef4_filter_init_rx(&spec, EF4_FILTER_PRI_HINT,
853			   efx->rx_scatter ? EF4_FILTER_FLAG_RX_SCATTER : 0,
854			   rxq_index);
855	spec.match_flags =
856		EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_IP_PROTO |
857		EF4_FILTER_MATCH_LOC_HOST | EF4_FILTER_MATCH_LOC_PORT |
858		EF4_FILTER_MATCH_REM_HOST | EF4_FILTER_MATCH_REM_PORT;
859	spec.ether_type = fk.basic.n_proto;
860	spec.ip_proto = fk.basic.ip_proto;
861
862	if (fk.basic.n_proto == htons(ETH_P_IP)) {
863		spec.rem_host[0] = fk.addrs.v4addrs.src;
864		spec.loc_host[0] = fk.addrs.v4addrs.dst;
865	} else {
866		memcpy(spec.rem_host, &fk.addrs.v6addrs.src, sizeof(struct in6_addr));
867		memcpy(spec.loc_host, &fk.addrs.v6addrs.dst, sizeof(struct in6_addr));
868	}
869
870	spec.rem_port = fk.ports.src;
871	spec.loc_port = fk.ports.dst;
872
873	rc = efx->type->filter_rfs_insert(efx, &spec);
874	if (rc < 0)
875		return rc;
876
877	/* Remember this so we can check whether to expire the filter later */
878	channel = ef4_get_channel(efx, rxq_index);
879	channel->rps_flow_id[rc] = flow_id;
880	++channel->rfs_filters_added;
881
882	if (spec.ether_type == htons(ETH_P_IP))
883		netif_info(efx, rx_status, efx->net_dev,
884			   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
885			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
886			   spec.rem_host, ntohs(spec.rem_port), spec.loc_host,
887			   ntohs(spec.loc_port), rxq_index, flow_id, rc);
888	else
889		netif_info(efx, rx_status, efx->net_dev,
890			   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
891			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
892			   spec.rem_host, ntohs(spec.rem_port), spec.loc_host,
893			   ntohs(spec.loc_port), rxq_index, flow_id, rc);
894
895	return rc;
896}
897
898bool __ef4_filter_rfs_expire(struct ef4_nic *efx, unsigned int quota)
899{
900	bool (*expire_one)(struct ef4_nic *efx, u32 flow_id, unsigned int index);
901	unsigned int channel_idx, index, size;
902	u32 flow_id;
903
904	if (!spin_trylock_bh(&efx->filter_lock))
905		return false;
906
907	expire_one = efx->type->filter_rfs_expire_one;
908	channel_idx = efx->rps_expire_channel;
909	index = efx->rps_expire_index;
910	size = efx->type->max_rx_ip_filters;
911	while (quota--) {
912		struct ef4_channel *channel = ef4_get_channel(efx, channel_idx);
913		flow_id = channel->rps_flow_id[index];
914
915		if (flow_id != RPS_FLOW_ID_INVALID &&
916		    expire_one(efx, flow_id, index)) {
917			netif_info(efx, rx_status, efx->net_dev,
918				   "expired filter %d [queue %u flow %u]\n",
919				   index, channel_idx, flow_id);
920			channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;
921		}
922		if (++index == size) {
923			if (++channel_idx == efx->n_channels)
924				channel_idx = 0;
925			index = 0;
926		}
927	}
928	efx->rps_expire_channel = channel_idx;
929	efx->rps_expire_index = index;
930
931	spin_unlock_bh(&efx->filter_lock);
932	return true;
933}
934
935#endif /* CONFIG_RFS_ACCEL */
936
937/**
938 * ef4_filter_is_mc_recipient - test whether spec is a multicast recipient
939 * @spec: Specification to test
940 *
941 * Return: %true if the specification is a non-drop RX filter that
942 * matches a local MAC address I/G bit value of 1 or matches a local
943 * IPv4 or IPv6 address value in the respective multicast address
944 * range.  Otherwise %false.
945 */
946bool ef4_filter_is_mc_recipient(const struct ef4_filter_spec *spec)
947{
948	if (!(spec->flags & EF4_FILTER_FLAG_RX) ||
949	    spec->dmaq_id == EF4_FILTER_RX_DMAQ_ID_DROP)
950		return false;
951
952	if (spec->match_flags &
953	    (EF4_FILTER_MATCH_LOC_MAC | EF4_FILTER_MATCH_LOC_MAC_IG) &&
954	    is_multicast_ether_addr(spec->loc_mac))
955		return true;
956
957	if ((spec->match_flags &
958	     (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) ==
959	    (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) {
960		if (spec->ether_type == htons(ETH_P_IP) &&
961		    ipv4_is_multicast(spec->loc_host[0]))
962			return true;
963		if (spec->ether_type == htons(ETH_P_IPV6) &&
964		    ((const u8 *)spec->loc_host)[0] == 0xff)
965			return true;
966	}
967
968	return false;
969}