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v6.8
  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	if (unlikely(!rx_queue->page_ring))
114		return NULL;
115	index = rx_queue->page_remove & rx_queue->page_ptr_mask;
116	page = rx_queue->page_ring[index];
117	if (page == NULL)
118		return NULL;
119
120	rx_queue->page_ring[index] = NULL;
121	/* page_remove cannot exceed page_add. */
122	if (rx_queue->page_remove != rx_queue->page_add)
123		++rx_queue->page_remove;
124
125	/* If page_count is 1 then we hold the only reference to this page. */
126	if (page_count(page) == 1) {
127		++rx_queue->page_recycle_count;
128		return page;
129	} else {
130		state = page_address(page);
131		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
132			       PAGE_SIZE << efx->rx_buffer_order,
133			       DMA_FROM_DEVICE);
134		put_page(page);
135		++rx_queue->page_recycle_failed;
136	}
137
138	return NULL;
139}
140
141/**
142 * ef4_init_rx_buffers - create EF4_RX_BATCH page-based RX buffers
143 *
144 * @rx_queue:		Efx RX queue
145 * @atomic:		control memory allocation flags
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	if (unlikely(!rx_queue->page_ring))
299		return;
300
301	do {
302		ef4_recycle_rx_page(channel, rx_buf);
303		rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
304	} while (--n_frags);
305}
306
307static void ef4_discard_rx_packet(struct ef4_channel *channel,
308				  struct ef4_rx_buffer *rx_buf,
309				  unsigned int n_frags)
310{
311	struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
312
313	ef4_recycle_rx_pages(channel, rx_buf, n_frags);
314
315	ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
316}
317
318/**
319 * ef4_fast_push_rx_descriptors - push new RX descriptors quickly
320 * @rx_queue:		RX descriptor queue
321 *
322 * This will aim to fill the RX descriptor queue up to
323 * @rx_queue->@max_fill. If there is insufficient atomic
324 * memory to do so, a slow fill will be scheduled.
325 * @atomic: control memory allocation flags
326 *
327 * The caller must provide serialisation (none is used here). In practise,
328 * this means this function must run from the NAPI handler, or be called
329 * when NAPI is disabled.
330 */
331void ef4_fast_push_rx_descriptors(struct ef4_rx_queue *rx_queue, bool atomic)
332{
333	struct ef4_nic *efx = rx_queue->efx;
334	unsigned int fill_level, batch_size;
335	int space, rc = 0;
336
337	if (!rx_queue->refill_enabled)
338		return;
339
340	/* Calculate current fill level, and exit if we don't need to fill */
341	fill_level = (rx_queue->added_count - rx_queue->removed_count);
342	EF4_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
343	if (fill_level >= rx_queue->fast_fill_trigger)
344		goto out;
345
346	/* Record minimum fill level */
347	if (unlikely(fill_level < rx_queue->min_fill)) {
348		if (fill_level)
349			rx_queue->min_fill = fill_level;
350	}
351
352	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
353	space = rx_queue->max_fill - fill_level;
354	EF4_BUG_ON_PARANOID(space < batch_size);
355
356	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
357		   "RX queue %d fast-filling descriptor ring from"
358		   " level %d to level %d\n",
359		   ef4_rx_queue_index(rx_queue), fill_level,
360		   rx_queue->max_fill);
361
362
363	do {
364		rc = ef4_init_rx_buffers(rx_queue, atomic);
365		if (unlikely(rc)) {
366			/* Ensure that we don't leave the rx queue empty */
367			if (rx_queue->added_count == rx_queue->removed_count)
368				ef4_schedule_slow_fill(rx_queue);
369			goto out;
370		}
371	} while ((space -= batch_size) >= batch_size);
372
373	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
374		   "RX queue %d fast-filled descriptor ring "
375		   "to level %d\n", ef4_rx_queue_index(rx_queue),
376		   rx_queue->added_count - rx_queue->removed_count);
377
378 out:
379	if (rx_queue->notified_count != rx_queue->added_count)
380		ef4_nic_notify_rx_desc(rx_queue);
381}
382
383void ef4_rx_slow_fill(struct timer_list *t)
384{
385	struct ef4_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);
386
387	/* Post an event to cause NAPI to run and refill the queue */
388	ef4_nic_generate_fill_event(rx_queue);
389	++rx_queue->slow_fill_count;
390}
391
392static void ef4_rx_packet__check_len(struct ef4_rx_queue *rx_queue,
393				     struct ef4_rx_buffer *rx_buf,
394				     int len)
395{
396	struct ef4_nic *efx = rx_queue->efx;
397	unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
398
399	if (likely(len <= max_len))
400		return;
401
402	/* The packet must be discarded, but this is only a fatal error
403	 * if the caller indicated it was
404	 */
405	rx_buf->flags |= EF4_RX_PKT_DISCARD;
406
407	if ((len > rx_buf->len) && EF4_WORKAROUND_8071(efx)) {
408		if (net_ratelimit())
409			netif_err(efx, rx_err, efx->net_dev,
410				  " RX queue %d seriously overlength "
411				  "RX event (0x%x > 0x%x+0x%x). Leaking\n",
412				  ef4_rx_queue_index(rx_queue), len, max_len,
413				  efx->type->rx_buffer_padding);
414		ef4_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
415	} else {
416		if (net_ratelimit())
417			netif_err(efx, rx_err, efx->net_dev,
418				  " RX queue %d overlength RX event "
419				  "(0x%x > 0x%x)\n",
420				  ef4_rx_queue_index(rx_queue), len, max_len);
421	}
422
423	ef4_rx_queue_channel(rx_queue)->n_rx_overlength++;
424}
425
426/* Pass a received packet up through GRO.  GRO can handle pages
427 * regardless of checksum state and skbs with a good checksum.
428 */
429static void
430ef4_rx_packet_gro(struct ef4_channel *channel, struct ef4_rx_buffer *rx_buf,
431		  unsigned int n_frags, u8 *eh)
432{
433	struct napi_struct *napi = &channel->napi_str;
434	struct ef4_nic *efx = channel->efx;
435	struct sk_buff *skb;
436
437	skb = napi_get_frags(napi);
438	if (unlikely(!skb)) {
439		struct ef4_rx_queue *rx_queue;
440
441		rx_queue = ef4_channel_get_rx_queue(channel);
442		ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
443		return;
444	}
445
446	if (efx->net_dev->features & NETIF_F_RXHASH)
447		skb_set_hash(skb, ef4_rx_buf_hash(efx, eh),
448			     PKT_HASH_TYPE_L3);
449	skb->ip_summed = ((rx_buf->flags & EF4_RX_PKT_CSUMMED) ?
450			  CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
451
452	for (;;) {
453		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
454				   rx_buf->page, rx_buf->page_offset,
455				   rx_buf->len);
456		rx_buf->page = NULL;
457		skb->len += rx_buf->len;
458		if (skb_shinfo(skb)->nr_frags == n_frags)
459			break;
460
461		rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
462	}
463
464	skb->data_len = skb->len;
465	skb->truesize += n_frags * efx->rx_buffer_truesize;
466
467	skb_record_rx_queue(skb, channel->rx_queue.core_index);
468
469	napi_gro_frags(napi);
470}
471
472/* Allocate and construct an SKB around page fragments */
473static struct sk_buff *ef4_rx_mk_skb(struct ef4_channel *channel,
474				     struct ef4_rx_buffer *rx_buf,
475				     unsigned int n_frags,
476				     u8 *eh, int hdr_len)
477{
478	struct ef4_nic *efx = channel->efx;
479	struct sk_buff *skb;
480
481	/* Allocate an SKB to store the headers */
482	skb = netdev_alloc_skb(efx->net_dev,
483			       efx->rx_ip_align + efx->rx_prefix_size +
484			       hdr_len);
485	if (unlikely(skb == NULL)) {
486		atomic_inc(&efx->n_rx_noskb_drops);
487		return NULL;
488	}
489
490	EF4_BUG_ON_PARANOID(rx_buf->len < hdr_len);
491
492	memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
493	       efx->rx_prefix_size + hdr_len);
494	skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
495	__skb_put(skb, hdr_len);
496
497	/* Append the remaining page(s) onto the frag list */
498	if (rx_buf->len > hdr_len) {
499		rx_buf->page_offset += hdr_len;
500		rx_buf->len -= hdr_len;
501
502		for (;;) {
503			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
504					   rx_buf->page, rx_buf->page_offset,
505					   rx_buf->len);
506			rx_buf->page = NULL;
507			skb->len += rx_buf->len;
508			skb->data_len += rx_buf->len;
509			if (skb_shinfo(skb)->nr_frags == n_frags)
510				break;
511
512			rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
513		}
514	} else {
515		__free_pages(rx_buf->page, efx->rx_buffer_order);
516		rx_buf->page = NULL;
517		n_frags = 0;
518	}
519
520	skb->truesize += n_frags * efx->rx_buffer_truesize;
521
522	/* Move past the ethernet header */
523	skb->protocol = eth_type_trans(skb, efx->net_dev);
524
525	skb_mark_napi_id(skb, &channel->napi_str);
526
527	return skb;
528}
529
530void ef4_rx_packet(struct ef4_rx_queue *rx_queue, unsigned int index,
531		   unsigned int n_frags, unsigned int len, u16 flags)
532{
533	struct ef4_nic *efx = rx_queue->efx;
534	struct ef4_channel *channel = ef4_rx_queue_channel(rx_queue);
535	struct ef4_rx_buffer *rx_buf;
536
537	rx_queue->rx_packets++;
538
539	rx_buf = ef4_rx_buffer(rx_queue, index);
540	rx_buf->flags |= flags;
541
542	/* Validate the number of fragments and completed length */
543	if (n_frags == 1) {
544		if (!(flags & EF4_RX_PKT_PREFIX_LEN))
545			ef4_rx_packet__check_len(rx_queue, rx_buf, len);
546	} else if (unlikely(n_frags > EF4_RX_MAX_FRAGS) ||
547		   unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
548		   unlikely(len > n_frags * efx->rx_dma_len) ||
549		   unlikely(!efx->rx_scatter)) {
550		/* If this isn't an explicit discard request, either
551		 * the hardware or the driver is broken.
552		 */
553		WARN_ON(!(len == 0 && rx_buf->flags & EF4_RX_PKT_DISCARD));
554		rx_buf->flags |= EF4_RX_PKT_DISCARD;
555	}
556
557	netif_vdbg(efx, rx_status, efx->net_dev,
558		   "RX queue %d received ids %x-%x len %d %s%s\n",
559		   ef4_rx_queue_index(rx_queue), index,
560		   (index + n_frags - 1) & rx_queue->ptr_mask, len,
561		   (rx_buf->flags & EF4_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
562		   (rx_buf->flags & EF4_RX_PKT_DISCARD) ? " [DISCARD]" : "");
563
564	/* Discard packet, if instructed to do so.  Process the
565	 * previous receive first.
566	 */
567	if (unlikely(rx_buf->flags & EF4_RX_PKT_DISCARD)) {
568		ef4_rx_flush_packet(channel);
569		ef4_discard_rx_packet(channel, rx_buf, n_frags);
570		return;
571	}
572
573	if (n_frags == 1 && !(flags & EF4_RX_PKT_PREFIX_LEN))
574		rx_buf->len = len;
575
576	/* Release and/or sync the DMA mapping - assumes all RX buffers
577	 * consumed in-order per RX queue.
578	 */
579	ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
580
581	/* Prefetch nice and early so data will (hopefully) be in cache by
582	 * the time we look at it.
583	 */
584	prefetch(ef4_rx_buf_va(rx_buf));
585
586	rx_buf->page_offset += efx->rx_prefix_size;
587	rx_buf->len -= efx->rx_prefix_size;
588
589	if (n_frags > 1) {
590		/* Release/sync DMA mapping for additional fragments.
591		 * Fix length for last fragment.
592		 */
593		unsigned int tail_frags = n_frags - 1;
594
595		for (;;) {
596			rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
597			if (--tail_frags == 0)
598				break;
599			ef4_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
600		}
601		rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
602		ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
603	}
604
605	/* All fragments have been DMA-synced, so recycle pages. */
606	rx_buf = ef4_rx_buffer(rx_queue, index);
607	ef4_recycle_rx_pages(channel, rx_buf, n_frags);
608
609	/* Pipeline receives so that we give time for packet headers to be
610	 * prefetched into cache.
611	 */
612	ef4_rx_flush_packet(channel);
613	channel->rx_pkt_n_frags = n_frags;
614	channel->rx_pkt_index = index;
615}
616
617static void ef4_rx_deliver(struct ef4_channel *channel, u8 *eh,
618			   struct ef4_rx_buffer *rx_buf,
619			   unsigned int n_frags)
620{
621	struct sk_buff *skb;
622	u16 hdr_len = min_t(u16, rx_buf->len, EF4_SKB_HEADERS);
623
624	skb = ef4_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
625	if (unlikely(skb == NULL)) {
626		struct ef4_rx_queue *rx_queue;
627
628		rx_queue = ef4_channel_get_rx_queue(channel);
629		ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
630		return;
631	}
632	skb_record_rx_queue(skb, channel->rx_queue.core_index);
633
634	/* Set the SKB flags */
635	skb_checksum_none_assert(skb);
636	if (likely(rx_buf->flags & EF4_RX_PKT_CSUMMED))
637		skb->ip_summed = CHECKSUM_UNNECESSARY;
638
639	if (channel->type->receive_skb)
640		if (channel->type->receive_skb(channel, skb))
641			return;
642
643	/* Pass the packet up */
644	netif_receive_skb(skb);
645}
646
647/* Handle a received packet.  Second half: Touches packet payload. */
648void __ef4_rx_packet(struct ef4_channel *channel)
649{
650	struct ef4_nic *efx = channel->efx;
651	struct ef4_rx_buffer *rx_buf =
652		ef4_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
653	u8 *eh = ef4_rx_buf_va(rx_buf);
654
655	/* Read length from the prefix if necessary.  This already
656	 * excludes the length of the prefix itself.
657	 */
658	if (rx_buf->flags & EF4_RX_PKT_PREFIX_LEN)
659		rx_buf->len = le16_to_cpup((__le16 *)
660					   (eh + efx->rx_packet_len_offset));
661
662	/* If we're in loopback test, then pass the packet directly to the
663	 * loopback layer, and free the rx_buf here
664	 */
665	if (unlikely(efx->loopback_selftest)) {
666		struct ef4_rx_queue *rx_queue;
667
668		ef4_loopback_rx_packet(efx, eh, rx_buf->len);
669		rx_queue = ef4_channel_get_rx_queue(channel);
670		ef4_free_rx_buffers(rx_queue, rx_buf,
671				    channel->rx_pkt_n_frags);
672		goto out;
673	}
674
675	if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
676		rx_buf->flags &= ~EF4_RX_PKT_CSUMMED;
677
678	if ((rx_buf->flags & EF4_RX_PKT_TCP) && !channel->type->receive_skb)
679		ef4_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
680	else
681		ef4_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
682out:
683	channel->rx_pkt_n_frags = 0;
684}
685
686int ef4_probe_rx_queue(struct ef4_rx_queue *rx_queue)
687{
688	struct ef4_nic *efx = rx_queue->efx;
689	unsigned int entries;
690	int rc;
691
692	/* Create the smallest power-of-two aligned ring */
693	entries = max(roundup_pow_of_two(efx->rxq_entries), EF4_MIN_DMAQ_SIZE);
694	EF4_BUG_ON_PARANOID(entries > EF4_MAX_DMAQ_SIZE);
695	rx_queue->ptr_mask = entries - 1;
696
697	netif_dbg(efx, probe, efx->net_dev,
698		  "creating RX queue %d size %#x mask %#x\n",
699		  ef4_rx_queue_index(rx_queue), efx->rxq_entries,
700		  rx_queue->ptr_mask);
701
702	/* Allocate RX buffers */
703	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
704				   GFP_KERNEL);
705	if (!rx_queue->buffer)
706		return -ENOMEM;
707
708	rc = ef4_nic_probe_rx(rx_queue);
709	if (rc) {
710		kfree(rx_queue->buffer);
711		rx_queue->buffer = NULL;
712	}
713
714	return rc;
715}
716
717static void ef4_init_rx_recycle_ring(struct ef4_nic *efx,
718				     struct ef4_rx_queue *rx_queue)
719{
720	unsigned int bufs_in_recycle_ring, page_ring_size;
721	struct iommu_domain __maybe_unused *domain;
722
723	/* Set the RX recycle ring size */
724#ifdef CONFIG_PPC64
725	bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
726#else
727	domain = iommu_get_domain_for_dev(&efx->pci_dev->dev);
728	if (domain && domain->type != IOMMU_DOMAIN_IDENTITY)
729		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
730	else
731		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_NOIOMMU;
732#endif /* CONFIG_PPC64 */
733
734	page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /
735					    efx->rx_bufs_per_page);
736	rx_queue->page_ring = kcalloc(page_ring_size,
737				      sizeof(*rx_queue->page_ring), GFP_KERNEL);
738	if (!rx_queue->page_ring)
739		rx_queue->page_ptr_mask = 0;
740	else
741		rx_queue->page_ptr_mask = page_ring_size - 1;
742}
743
744void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue)
745{
746	struct ef4_nic *efx = rx_queue->efx;
747	unsigned int max_fill, trigger, max_trigger;
748
749	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
750		  "initialising RX queue %d\n", ef4_rx_queue_index(rx_queue));
751
752	/* Initialise ptr fields */
753	rx_queue->added_count = 0;
754	rx_queue->notified_count = 0;
755	rx_queue->removed_count = 0;
756	rx_queue->min_fill = -1U;
757	ef4_init_rx_recycle_ring(efx, rx_queue);
758
759	rx_queue->page_remove = 0;
760	rx_queue->page_add = rx_queue->page_ptr_mask + 1;
761	rx_queue->page_recycle_count = 0;
762	rx_queue->page_recycle_failed = 0;
763	rx_queue->page_recycle_full = 0;
764
765	/* Initialise limit fields */
766	max_fill = efx->rxq_entries - EF4_RXD_HEAD_ROOM;
767	max_trigger =
768		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
769	if (rx_refill_threshold != 0) {
770		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
771		if (trigger > max_trigger)
772			trigger = max_trigger;
773	} else {
774		trigger = max_trigger;
775	}
776
777	rx_queue->max_fill = max_fill;
778	rx_queue->fast_fill_trigger = trigger;
779	rx_queue->refill_enabled = true;
780
781	/* Set up RX descriptor ring */
782	ef4_nic_init_rx(rx_queue);
783}
784
785void ef4_fini_rx_queue(struct ef4_rx_queue *rx_queue)
786{
787	int i;
788	struct ef4_nic *efx = rx_queue->efx;
789	struct ef4_rx_buffer *rx_buf;
790
791	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
792		  "shutting down RX queue %d\n", ef4_rx_queue_index(rx_queue));
793
794	del_timer_sync(&rx_queue->slow_fill);
795
796	/* Release RX buffers from the current read ptr to the write ptr */
797	if (rx_queue->buffer) {
798		for (i = rx_queue->removed_count; i < rx_queue->added_count;
799		     i++) {
800			unsigned index = i & rx_queue->ptr_mask;
801			rx_buf = ef4_rx_buffer(rx_queue, index);
802			ef4_fini_rx_buffer(rx_queue, rx_buf);
803		}
804	}
805
806	/* Unmap and release the pages in the recycle ring. Remove the ring. */
807	for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
808		struct page *page = rx_queue->page_ring[i];
809		struct ef4_rx_page_state *state;
810
811		if (page == NULL)
812			continue;
813
814		state = page_address(page);
815		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
816			       PAGE_SIZE << efx->rx_buffer_order,
817			       DMA_FROM_DEVICE);
818		put_page(page);
819	}
820	kfree(rx_queue->page_ring);
821	rx_queue->page_ring = NULL;
822}
823
824void ef4_remove_rx_queue(struct ef4_rx_queue *rx_queue)
825{
826	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
827		  "destroying RX queue %d\n", ef4_rx_queue_index(rx_queue));
828
829	ef4_nic_remove_rx(rx_queue);
830
831	kfree(rx_queue->buffer);
832	rx_queue->buffer = NULL;
833}
834
835
836module_param(rx_refill_threshold, uint, 0444);
837MODULE_PARM_DESC(rx_refill_threshold,
838		 "RX descriptor ring refill threshold (%)");
839
840#ifdef CONFIG_RFS_ACCEL
841
842int ef4_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
843		   u16 rxq_index, u32 flow_id)
844{
845	struct ef4_nic *efx = netdev_priv(net_dev);
846	struct ef4_channel *channel;
847	struct ef4_filter_spec spec;
848	struct flow_keys fk;
849	int rc;
850
851	if (flow_id == RPS_FLOW_ID_INVALID)
852		return -EINVAL;
853
854	if (!skb_flow_dissect_flow_keys(skb, &fk, 0))
855		return -EPROTONOSUPPORT;
856
857	if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6))
858		return -EPROTONOSUPPORT;
859	if (fk.control.flags & FLOW_DIS_IS_FRAGMENT)
860		return -EPROTONOSUPPORT;
861
862	ef4_filter_init_rx(&spec, EF4_FILTER_PRI_HINT,
863			   efx->rx_scatter ? EF4_FILTER_FLAG_RX_SCATTER : 0,
864			   rxq_index);
865	spec.match_flags =
866		EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_IP_PROTO |
867		EF4_FILTER_MATCH_LOC_HOST | EF4_FILTER_MATCH_LOC_PORT |
868		EF4_FILTER_MATCH_REM_HOST | EF4_FILTER_MATCH_REM_PORT;
869	spec.ether_type = fk.basic.n_proto;
870	spec.ip_proto = fk.basic.ip_proto;
871
872	if (fk.basic.n_proto == htons(ETH_P_IP)) {
873		spec.rem_host[0] = fk.addrs.v4addrs.src;
874		spec.loc_host[0] = fk.addrs.v4addrs.dst;
875	} else {
876		memcpy(spec.rem_host, &fk.addrs.v6addrs.src, sizeof(struct in6_addr));
877		memcpy(spec.loc_host, &fk.addrs.v6addrs.dst, sizeof(struct in6_addr));
878	}
879
880	spec.rem_port = fk.ports.src;
881	spec.loc_port = fk.ports.dst;
882
883	rc = efx->type->filter_rfs_insert(efx, &spec);
884	if (rc < 0)
885		return rc;
886
887	/* Remember this so we can check whether to expire the filter later */
888	channel = ef4_get_channel(efx, rxq_index);
889	channel->rps_flow_id[rc] = flow_id;
890	++channel->rfs_filters_added;
891
892	if (spec.ether_type == htons(ETH_P_IP))
893		netif_info(efx, rx_status, efx->net_dev,
894			   "steering %s %pI4:%u:%pI4:%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	else
899		netif_info(efx, rx_status, efx->net_dev,
900			   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
901			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
902			   spec.rem_host, ntohs(spec.rem_port), spec.loc_host,
903			   ntohs(spec.loc_port), rxq_index, flow_id, rc);
904
905	return rc;
906}
907
908bool __ef4_filter_rfs_expire(struct ef4_nic *efx, unsigned int quota)
909{
910	bool (*expire_one)(struct ef4_nic *efx, u32 flow_id, unsigned int index);
911	unsigned int channel_idx, index, size;
912	u32 flow_id;
913
914	if (!spin_trylock_bh(&efx->filter_lock))
915		return false;
916
917	expire_one = efx->type->filter_rfs_expire_one;
918	channel_idx = efx->rps_expire_channel;
919	index = efx->rps_expire_index;
920	size = efx->type->max_rx_ip_filters;
921	while (quota--) {
922		struct ef4_channel *channel = ef4_get_channel(efx, channel_idx);
923		flow_id = channel->rps_flow_id[index];
924
925		if (flow_id != RPS_FLOW_ID_INVALID &&
926		    expire_one(efx, flow_id, index)) {
927			netif_info(efx, rx_status, efx->net_dev,
928				   "expired filter %d [queue %u flow %u]\n",
929				   index, channel_idx, flow_id);
930			channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;
931		}
932		if (++index == size) {
933			if (++channel_idx == efx->n_channels)
934				channel_idx = 0;
935			index = 0;
936		}
937	}
938	efx->rps_expire_channel = channel_idx;
939	efx->rps_expire_index = index;
940
941	spin_unlock_bh(&efx->filter_lock);
942	return true;
943}
944
945#endif /* CONFIG_RFS_ACCEL */
946
947/**
948 * ef4_filter_is_mc_recipient - test whether spec is a multicast recipient
949 * @spec: Specification to test
950 *
951 * Return: %true if the specification is a non-drop RX filter that
952 * matches a local MAC address I/G bit value of 1 or matches a local
953 * IPv4 or IPv6 address value in the respective multicast address
954 * range.  Otherwise %false.
955 */
956bool ef4_filter_is_mc_recipient(const struct ef4_filter_spec *spec)
957{
958	if (!(spec->flags & EF4_FILTER_FLAG_RX) ||
959	    spec->dmaq_id == EF4_FILTER_RX_DMAQ_ID_DROP)
960		return false;
961
962	if (spec->match_flags &
963	    (EF4_FILTER_MATCH_LOC_MAC | EF4_FILTER_MATCH_LOC_MAC_IG) &&
964	    is_multicast_ether_addr(spec->loc_mac))
965		return true;
966
967	if ((spec->match_flags &
968	     (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) ==
969	    (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) {
970		if (spec->ether_type == htons(ETH_P_IP) &&
971		    ipv4_is_multicast(spec->loc_host[0]))
972			return true;
973		if (spec->ether_type == htons(ETH_P_IPV6) &&
974		    ((const u8 *)spec->loc_host)[0] == 0xff)
975			return true;
976	}
977
978	return false;
979}
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}