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1// SPDX-License-Identifier: GPL-2.0-only2/****************************************************************************3 * Driver for Solarflare network controllers and boards4 * Copyright 2018 Solarflare Communications Inc.5 *6 * This program is free software; you can redistribute it and/or modify it7 * under the terms of the GNU General Public License version 2 as published8 * by the Free Software Foundation, incorporated herein by reference.9 */10 11#include "net_driver.h"12#include <linux/module.h>13#include <linux/iommu.h>14#include <net/rps.h>15#include "efx.h"16#include "nic.h"17#include "rx_common.h"18 19/* This is the percentage fill level below which new RX descriptors20 * will be added to the RX descriptor ring.21 */22static unsigned int rx_refill_threshold;23module_param(rx_refill_threshold, uint, 0444);24MODULE_PARM_DESC(rx_refill_threshold,25		 "RX descriptor ring refill threshold (%)");26 27/* RX maximum head room required.28 *29 * This must be at least 1 to prevent overflow, plus one packet-worth30 * to allow pipelined receives.31 */32#define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS)33 34static void efx_unmap_rx_buffer(struct efx_nic *efx,35				struct efx_rx_buffer *rx_buf);36 37/* Check the RX page recycle ring for a page that can be reused. */38static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)39{40	struct efx_nic *efx = rx_queue->efx;41	struct efx_rx_page_state *state;42	unsigned int index;43	struct page *page;44 45	if (unlikely(!rx_queue->page_ring))46		return NULL;47	index = rx_queue->page_remove & rx_queue->page_ptr_mask;48	page = rx_queue->page_ring[index];49	if (page == NULL)50		return NULL;51 52	rx_queue->page_ring[index] = NULL;53	/* page_remove cannot exceed page_add. */54	if (rx_queue->page_remove != rx_queue->page_add)55		++rx_queue->page_remove;56 57	/* If page_count is 1 then we hold the only reference to this page. */58	if (page_count(page) == 1) {59		++rx_queue->page_recycle_count;60		return page;61	} else {62		state = page_address(page);63		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,64			       PAGE_SIZE << efx->rx_buffer_order,65			       DMA_FROM_DEVICE);66		put_page(page);67		++rx_queue->page_recycle_failed;68	}69 70	return NULL;71}72 73/* Attempt to recycle the page if there is an RX recycle ring; the page can74 * only be added if this is the final RX buffer, to prevent pages being used in75 * the descriptor ring and appearing in the recycle ring simultaneously.76 */77static void efx_recycle_rx_page(struct efx_channel *channel,78				struct efx_rx_buffer *rx_buf)79{80	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);81	struct efx_nic *efx = rx_queue->efx;82	struct page *page = rx_buf->page;83	unsigned int index;84 85	/* Only recycle the page after processing the final buffer. */86	if (!(rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE))87		return;88 89	index = rx_queue->page_add & rx_queue->page_ptr_mask;90	if (rx_queue->page_ring[index] == NULL) {91		unsigned int read_index = rx_queue->page_remove &92			rx_queue->page_ptr_mask;93 94		/* The next slot in the recycle ring is available, but95		 * increment page_remove if the read pointer currently96		 * points here.97		 */98		if (read_index == index)99			++rx_queue->page_remove;100		rx_queue->page_ring[index] = page;101		++rx_queue->page_add;102		return;103	}104	++rx_queue->page_recycle_full;105	efx_unmap_rx_buffer(efx, rx_buf);106	put_page(rx_buf->page);107}108 109/* Recycle the pages that are used by buffers that have just been received. */110void efx_siena_recycle_rx_pages(struct efx_channel *channel,111				struct efx_rx_buffer *rx_buf,112				unsigned int n_frags)113{114	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);115 116	if (unlikely(!rx_queue->page_ring))117		return;118 119	do {120		efx_recycle_rx_page(channel, rx_buf);121		rx_buf = efx_rx_buf_next(rx_queue, rx_buf);122	} while (--n_frags);123}124 125void efx_siena_discard_rx_packet(struct efx_channel *channel,126				 struct efx_rx_buffer *rx_buf,127				 unsigned int n_frags)128{129	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);130 131	efx_siena_recycle_rx_pages(channel, rx_buf, n_frags);132 133	efx_siena_free_rx_buffers(rx_queue, rx_buf, n_frags);134}135 136static void efx_init_rx_recycle_ring(struct efx_rx_queue *rx_queue)137{138	unsigned int bufs_in_recycle_ring, page_ring_size;139	struct efx_nic *efx = rx_queue->efx;140 141	bufs_in_recycle_ring = efx_rx_recycle_ring_size(efx);142	page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /143					    efx->rx_bufs_per_page);144	rx_queue->page_ring = kcalloc(page_ring_size,145				      sizeof(*rx_queue->page_ring), GFP_KERNEL);146	if (!rx_queue->page_ring)147		rx_queue->page_ptr_mask = 0;148	else149		rx_queue->page_ptr_mask = page_ring_size - 1;150}151 152static void efx_fini_rx_recycle_ring(struct efx_rx_queue *rx_queue)153{154	struct efx_nic *efx = rx_queue->efx;155	int i;156 157	if (unlikely(!rx_queue->page_ring))158		return;159 160	/* Unmap and release the pages in the recycle ring. Remove the ring. */161	for (i = 0; i <= rx_queue->page_ptr_mask; i++) {162		struct page *page = rx_queue->page_ring[i];163		struct efx_rx_page_state *state;164 165		if (page == NULL)166			continue;167 168		state = page_address(page);169		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,170			       PAGE_SIZE << efx->rx_buffer_order,171			       DMA_FROM_DEVICE);172		put_page(page);173	}174	kfree(rx_queue->page_ring);175	rx_queue->page_ring = NULL;176}177 178static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,179			       struct efx_rx_buffer *rx_buf)180{181	/* Release the page reference we hold for the buffer. */182	if (rx_buf->page)183		put_page(rx_buf->page);184 185	/* If this is the last buffer in a page, unmap and free it. */186	if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) {187		efx_unmap_rx_buffer(rx_queue->efx, rx_buf);188		efx_siena_free_rx_buffers(rx_queue, rx_buf, 1);189	}190	rx_buf->page = NULL;191}192 193int efx_siena_probe_rx_queue(struct efx_rx_queue *rx_queue)194{195	struct efx_nic *efx = rx_queue->efx;196	unsigned int entries;197	int rc;198 199	/* Create the smallest power-of-two aligned ring */200	entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);201	EFX_WARN_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);202	rx_queue->ptr_mask = entries - 1;203 204	netif_dbg(efx, probe, efx->net_dev,205		  "creating RX queue %d size %#x mask %#x\n",206		  efx_rx_queue_index(rx_queue), efx->rxq_entries,207		  rx_queue->ptr_mask);208 209	/* Allocate RX buffers */210	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),211				   GFP_KERNEL);212	if (!rx_queue->buffer)213		return -ENOMEM;214 215	rc = efx_nic_probe_rx(rx_queue);216	if (rc) {217		kfree(rx_queue->buffer);218		rx_queue->buffer = NULL;219	}220 221	return rc;222}223 224void efx_siena_init_rx_queue(struct efx_rx_queue *rx_queue)225{226	unsigned int max_fill, trigger, max_trigger;227	struct efx_nic *efx = rx_queue->efx;228	int rc = 0;229 230	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,231		  "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));232 233	/* Initialise ptr fields */234	rx_queue->added_count = 0;235	rx_queue->notified_count = 0;236	rx_queue->removed_count = 0;237	rx_queue->min_fill = -1U;238	efx_init_rx_recycle_ring(rx_queue);239 240	rx_queue->page_remove = 0;241	rx_queue->page_add = rx_queue->page_ptr_mask + 1;242	rx_queue->page_recycle_count = 0;243	rx_queue->page_recycle_failed = 0;244	rx_queue->page_recycle_full = 0;245 246	/* Initialise limit fields */247	max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;248	max_trigger =249		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;250	if (rx_refill_threshold != 0) {251		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;252		if (trigger > max_trigger)253			trigger = max_trigger;254	} else {255		trigger = max_trigger;256	}257 258	rx_queue->max_fill = max_fill;259	rx_queue->fast_fill_trigger = trigger;260	rx_queue->refill_enabled = true;261 262	/* Initialise XDP queue information */263	rc = xdp_rxq_info_reg(&rx_queue->xdp_rxq_info, efx->net_dev,264			      rx_queue->core_index, 0);265 266	if (rc) {267		netif_err(efx, rx_err, efx->net_dev,268			  "Failure to initialise XDP queue information rc=%d\n",269			  rc);270		efx->xdp_rxq_info_failed = true;271	} else {272		rx_queue->xdp_rxq_info_valid = true;273	}274 275	/* Set up RX descriptor ring */276	efx_nic_init_rx(rx_queue);277}278 279void efx_siena_fini_rx_queue(struct efx_rx_queue *rx_queue)280{281	struct efx_rx_buffer *rx_buf;282	int i;283 284	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,285		  "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));286 287	del_timer_sync(&rx_queue->slow_fill);288 289	/* Release RX buffers from the current read ptr to the write ptr */290	if (rx_queue->buffer) {291		for (i = rx_queue->removed_count; i < rx_queue->added_count;292		     i++) {293			unsigned int index = i & rx_queue->ptr_mask;294 295			rx_buf = efx_rx_buffer(rx_queue, index);296			efx_fini_rx_buffer(rx_queue, rx_buf);297		}298	}299 300	efx_fini_rx_recycle_ring(rx_queue);301 302	if (rx_queue->xdp_rxq_info_valid)303		xdp_rxq_info_unreg(&rx_queue->xdp_rxq_info);304 305	rx_queue->xdp_rxq_info_valid = false;306}307 308void efx_siena_remove_rx_queue(struct efx_rx_queue *rx_queue)309{310	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,311		  "destroying RX queue %d\n", efx_rx_queue_index(rx_queue));312 313	efx_nic_remove_rx(rx_queue);314 315	kfree(rx_queue->buffer);316	rx_queue->buffer = NULL;317}318 319/* Unmap a DMA-mapped page.  This function is only called for the final RX320 * buffer in a page.321 */322static void efx_unmap_rx_buffer(struct efx_nic *efx,323				struct efx_rx_buffer *rx_buf)324{325	struct page *page = rx_buf->page;326 327	if (page) {328		struct efx_rx_page_state *state = page_address(page);329 330		dma_unmap_page(&efx->pci_dev->dev,331			       state->dma_addr,332			       PAGE_SIZE << efx->rx_buffer_order,333			       DMA_FROM_DEVICE);334	}335}336 337void efx_siena_free_rx_buffers(struct efx_rx_queue *rx_queue,338			       struct efx_rx_buffer *rx_buf,339			       unsigned int num_bufs)340{341	do {342		if (rx_buf->page) {343			put_page(rx_buf->page);344			rx_buf->page = NULL;345		}346		rx_buf = efx_rx_buf_next(rx_queue, rx_buf);347	} while (--num_bufs);348}349 350void efx_siena_rx_slow_fill(struct timer_list *t)351{352	struct efx_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);353 354	/* Post an event to cause NAPI to run and refill the queue */355	efx_nic_generate_fill_event(rx_queue);356	++rx_queue->slow_fill_count;357}358 359static void efx_schedule_slow_fill(struct efx_rx_queue *rx_queue)360{361	mod_timer(&rx_queue->slow_fill, jiffies + msecs_to_jiffies(10));362}363 364/* efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers365 *366 * @rx_queue:		Efx RX queue367 *368 * This allocates a batch of pages, maps them for DMA, and populates369 * struct efx_rx_buffers for each one. Return a negative error code or370 * 0 on success. If a single page can be used for multiple buffers,371 * then the page will either be inserted fully, or not at all.372 */373static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue, bool atomic)374{375	unsigned int page_offset, index, count;376	struct efx_nic *efx = rx_queue->efx;377	struct efx_rx_page_state *state;378	struct efx_rx_buffer *rx_buf;379	dma_addr_t dma_addr;380	struct page *page;381 382	count = 0;383	do {384		page = efx_reuse_page(rx_queue);385		if (page == NULL) {386			page = alloc_pages(__GFP_COMP |387					   (atomic ? GFP_ATOMIC : GFP_KERNEL),388					   efx->rx_buffer_order);389			if (unlikely(page == NULL))390				return -ENOMEM;391			dma_addr =392				dma_map_page(&efx->pci_dev->dev, page, 0,393					     PAGE_SIZE << efx->rx_buffer_order,394					     DMA_FROM_DEVICE);395			if (unlikely(dma_mapping_error(&efx->pci_dev->dev,396						       dma_addr))) {397				__free_pages(page, efx->rx_buffer_order);398				return -EIO;399			}400			state = page_address(page);401			state->dma_addr = dma_addr;402		} else {403			state = page_address(page);404			dma_addr = state->dma_addr;405		}406 407		dma_addr += sizeof(struct efx_rx_page_state);408		page_offset = sizeof(struct efx_rx_page_state);409 410		do {411			index = rx_queue->added_count & rx_queue->ptr_mask;412			rx_buf = efx_rx_buffer(rx_queue, index);413			rx_buf->dma_addr = dma_addr + efx->rx_ip_align +414					   EFX_XDP_HEADROOM;415			rx_buf->page = page;416			rx_buf->page_offset = page_offset + efx->rx_ip_align +417					      EFX_XDP_HEADROOM;418			rx_buf->len = efx->rx_dma_len;419			rx_buf->flags = 0;420			++rx_queue->added_count;421			get_page(page);422			dma_addr += efx->rx_page_buf_step;423			page_offset += efx->rx_page_buf_step;424		} while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE);425 426		rx_buf->flags = EFX_RX_BUF_LAST_IN_PAGE;427	} while (++count < efx->rx_pages_per_batch);428 429	return 0;430}431 432void efx_siena_rx_config_page_split(struct efx_nic *efx)433{434	efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align +435				      EFX_XDP_HEADROOM + EFX_XDP_TAILROOM,436				      EFX_RX_BUF_ALIGNMENT);437	efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :438		((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /439		efx->rx_page_buf_step);440	efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /441		efx->rx_bufs_per_page;442	efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH,443					       efx->rx_bufs_per_page);444}445 446/* efx_siena_fast_push_rx_descriptors - push new RX descriptors quickly447 * @rx_queue:		RX descriptor queue448 *449 * This will aim to fill the RX descriptor queue up to450 * @rx_queue->@max_fill. If there is insufficient atomic451 * memory to do so, a slow fill will be scheduled.452 *453 * The caller must provide serialisation (none is used here). In practise,454 * this means this function must run from the NAPI handler, or be called455 * when NAPI is disabled.456 */457void efx_siena_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue,458					bool atomic)459{460	struct efx_nic *efx = rx_queue->efx;461	unsigned int fill_level, batch_size;462	int space, rc = 0;463 464	if (!rx_queue->refill_enabled)465		return;466 467	/* Calculate current fill level, and exit if we don't need to fill */468	fill_level = (rx_queue->added_count - rx_queue->removed_count);469	EFX_WARN_ON_ONCE_PARANOID(fill_level > rx_queue->efx->rxq_entries);470	if (fill_level >= rx_queue->fast_fill_trigger)471		goto out;472 473	/* Record minimum fill level */474	if (unlikely(fill_level < rx_queue->min_fill)) {475		if (fill_level)476			rx_queue->min_fill = fill_level;477	}478 479	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;480	space = rx_queue->max_fill - fill_level;481	EFX_WARN_ON_ONCE_PARANOID(space < batch_size);482 483	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,484		   "RX queue %d fast-filling descriptor ring from"485		   " level %d to level %d\n",486		   efx_rx_queue_index(rx_queue), fill_level,487		   rx_queue->max_fill);488 489	do {490		rc = efx_init_rx_buffers(rx_queue, atomic);491		if (unlikely(rc)) {492			/* Ensure that we don't leave the rx queue empty */493			efx_schedule_slow_fill(rx_queue);494			goto out;495		}496	} while ((space -= batch_size) >= batch_size);497 498	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,499		   "RX queue %d fast-filled descriptor ring "500		   "to level %d\n", efx_rx_queue_index(rx_queue),501		   rx_queue->added_count - rx_queue->removed_count);502 503 out:504	if (rx_queue->notified_count != rx_queue->added_count)505		efx_nic_notify_rx_desc(rx_queue);506}507 508/* Pass a received packet up through GRO.  GRO can handle pages509 * regardless of checksum state and skbs with a good checksum.510 */511void512efx_siena_rx_packet_gro(struct efx_channel *channel,513			struct efx_rx_buffer *rx_buf,514			unsigned int n_frags, u8 *eh, __wsum csum)515{516	struct napi_struct *napi = &channel->napi_str;517	struct efx_nic *efx = channel->efx;518	struct sk_buff *skb;519 520	skb = napi_get_frags(napi);521	if (unlikely(!skb)) {522		struct efx_rx_queue *rx_queue;523 524		rx_queue = efx_channel_get_rx_queue(channel);525		efx_siena_free_rx_buffers(rx_queue, rx_buf, n_frags);526		return;527	}528 529	if (efx->net_dev->features & NETIF_F_RXHASH)530		skb_set_hash(skb, efx_rx_buf_hash(efx, eh),531			     PKT_HASH_TYPE_L3);532	if (csum) {533		skb->csum = csum;534		skb->ip_summed = CHECKSUM_COMPLETE;535	} else {536		skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?537				  CHECKSUM_UNNECESSARY : CHECKSUM_NONE);538	}539	skb->csum_level = !!(rx_buf->flags & EFX_RX_PKT_CSUM_LEVEL);540 541	for (;;) {542		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,543				   rx_buf->page, rx_buf->page_offset,544				   rx_buf->len);545		rx_buf->page = NULL;546		skb->len += rx_buf->len;547		if (skb_shinfo(skb)->nr_frags == n_frags)548			break;549 550		rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);551	}552 553	skb->data_len = skb->len;554	skb->truesize += n_frags * efx->rx_buffer_truesize;555 556	skb_record_rx_queue(skb, channel->rx_queue.core_index);557 558	napi_gro_frags(napi);559}560 561void efx_siena_set_default_rx_indir_table(struct efx_nic *efx,562					  struct efx_rss_context *ctx)563{564	size_t i;565 566	for (i = 0; i < ARRAY_SIZE(ctx->rx_indir_table); i++)567		ctx->rx_indir_table[i] =568			ethtool_rxfh_indir_default(i, efx->rss_spread);569}570 571/**572 * efx_siena_filter_is_mc_recipient - test whether spec is a multicast recipient573 * @spec: Specification to test574 *575 * Return: %true if the specification is a non-drop RX filter that576 * matches a local MAC address I/G bit value of 1 or matches a local577 * IPv4 or IPv6 address value in the respective multicast address578 * range.  Otherwise %false.579 */580bool efx_siena_filter_is_mc_recipient(const struct efx_filter_spec *spec)581{582	if (!(spec->flags & EFX_FILTER_FLAG_RX) ||583	    spec->dmaq_id == EFX_FILTER_RX_DMAQ_ID_DROP)584		return false;585 586	if (spec->match_flags &587	    (EFX_FILTER_MATCH_LOC_MAC | EFX_FILTER_MATCH_LOC_MAC_IG) &&588	    is_multicast_ether_addr(spec->loc_mac))589		return true;590 591	if ((spec->match_flags &592	     (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) ==593	    (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) {594		if (spec->ether_type == htons(ETH_P_IP) &&595		    ipv4_is_multicast(spec->loc_host[0]))596			return true;597		if (spec->ether_type == htons(ETH_P_IPV6) &&598		    ((const u8 *)spec->loc_host)[0] == 0xff)599			return true;600	}601 602	return false;603}604 605bool efx_siena_filter_spec_equal(const struct efx_filter_spec *left,606				 const struct efx_filter_spec *right)607{608	if ((left->match_flags ^ right->match_flags) |609	    ((left->flags ^ right->flags) &610	     (EFX_FILTER_FLAG_RX | EFX_FILTER_FLAG_TX)))611		return false;612 613	return memcmp(&left->outer_vid, &right->outer_vid,614		      sizeof(struct efx_filter_spec) -615		      offsetof(struct efx_filter_spec, outer_vid)) == 0;616}617 618u32 efx_siena_filter_spec_hash(const struct efx_filter_spec *spec)619{620	BUILD_BUG_ON(offsetof(struct efx_filter_spec, outer_vid) & 3);621	return jhash2((const u32 *)&spec->outer_vid,622		      (sizeof(struct efx_filter_spec) -623		       offsetof(struct efx_filter_spec, outer_vid)) / 4,624		      0);625}626 627#ifdef CONFIG_RFS_ACCEL628bool efx_siena_rps_check_rule(struct efx_arfs_rule *rule,629			      unsigned int filter_idx, bool *force)630{631	if (rule->filter_id == EFX_ARFS_FILTER_ID_PENDING) {632		/* ARFS is currently updating this entry, leave it */633		return false;634	}635	if (rule->filter_id == EFX_ARFS_FILTER_ID_ERROR) {636		/* ARFS tried and failed to update this, so it's probably out637		 * of date.  Remove the filter and the ARFS rule entry.638		 */639		rule->filter_id = EFX_ARFS_FILTER_ID_REMOVING;640		*force = true;641		return true;642	} else if (WARN_ON(rule->filter_id != filter_idx)) { /* can't happen */643		/* ARFS has moved on, so old filter is not needed.  Since we did644		 * not mark the rule with EFX_ARFS_FILTER_ID_REMOVING, it will645		 * not be removed by efx_siena_rps_hash_del() subsequently.646		 */647		*force = true;648		return true;649	}650	/* Remove it iff ARFS wants to. */651	return true;652}653 654static655struct hlist_head *efx_rps_hash_bucket(struct efx_nic *efx,656				       const struct efx_filter_spec *spec)657{658	u32 hash = efx_siena_filter_spec_hash(spec);659 660	lockdep_assert_held(&efx->rps_hash_lock);661	if (!efx->rps_hash_table)662		return NULL;663	return &efx->rps_hash_table[hash % EFX_ARFS_HASH_TABLE_SIZE];664}665 666struct efx_arfs_rule *efx_siena_rps_hash_find(struct efx_nic *efx,667					const struct efx_filter_spec *spec)668{669	struct efx_arfs_rule *rule;670	struct hlist_head *head;671	struct hlist_node *node;672 673	head = efx_rps_hash_bucket(efx, spec);674	if (!head)675		return NULL;676	hlist_for_each(node, head) {677		rule = container_of(node, struct efx_arfs_rule, node);678		if (efx_siena_filter_spec_equal(spec, &rule->spec))679			return rule;680	}681	return NULL;682}683 684static struct efx_arfs_rule *efx_rps_hash_add(struct efx_nic *efx,685					const struct efx_filter_spec *spec,686					bool *new)687{688	struct efx_arfs_rule *rule;689	struct hlist_head *head;690	struct hlist_node *node;691 692	head = efx_rps_hash_bucket(efx, spec);693	if (!head)694		return NULL;695	hlist_for_each(node, head) {696		rule = container_of(node, struct efx_arfs_rule, node);697		if (efx_siena_filter_spec_equal(spec, &rule->spec)) {698			*new = false;699			return rule;700		}701	}702	rule = kmalloc(sizeof(*rule), GFP_ATOMIC);703	*new = true;704	if (rule) {705		memcpy(&rule->spec, spec, sizeof(rule->spec));706		hlist_add_head(&rule->node, head);707	}708	return rule;709}710 711void efx_siena_rps_hash_del(struct efx_nic *efx,712			    const struct efx_filter_spec *spec)713{714	struct efx_arfs_rule *rule;715	struct hlist_head *head;716	struct hlist_node *node;717 718	head = efx_rps_hash_bucket(efx, spec);719	if (WARN_ON(!head))720		return;721	hlist_for_each(node, head) {722		rule = container_of(node, struct efx_arfs_rule, node);723		if (efx_siena_filter_spec_equal(spec, &rule->spec)) {724			/* Someone already reused the entry.  We know that if725			 * this check doesn't fire (i.e. filter_id == REMOVING)726			 * then the REMOVING mark was put there by our caller,727			 * because caller is holding a lock on filter table and728			 * only holders of that lock set REMOVING.729			 */730			if (rule->filter_id != EFX_ARFS_FILTER_ID_REMOVING)731				return;732			hlist_del(node);733			kfree(rule);734			return;735		}736	}737	/* We didn't find it. */738	WARN_ON(1);739}740#endif741 742int efx_siena_probe_filters(struct efx_nic *efx)743{744	int rc;745 746	mutex_lock(&efx->mac_lock);747	down_write(&efx->filter_sem);748	rc = efx->type->filter_table_probe(efx);749	if (rc)750		goto out_unlock;751 752#ifdef CONFIG_RFS_ACCEL753	if (efx->type->offload_features & NETIF_F_NTUPLE) {754		struct efx_channel *channel;755		int i, success = 1;756 757		efx_for_each_channel(channel, efx) {758			channel->rps_flow_id =759				kcalloc(efx->type->max_rx_ip_filters,760					sizeof(*channel->rps_flow_id),761					GFP_KERNEL);762			if (!channel->rps_flow_id)763				success = 0;764			else765				for (i = 0;766				     i < efx->type->max_rx_ip_filters;767				     ++i)768					channel->rps_flow_id[i] =769						RPS_FLOW_ID_INVALID;770			channel->rfs_expire_index = 0;771			channel->rfs_filter_count = 0;772		}773 774		if (!success) {775			efx_for_each_channel(channel, efx)776				kfree(channel->rps_flow_id);777			efx->type->filter_table_remove(efx);778			rc = -ENOMEM;779			goto out_unlock;780		}781	}782#endif783out_unlock:784	up_write(&efx->filter_sem);785	mutex_unlock(&efx->mac_lock);786	return rc;787}788 789void efx_siena_remove_filters(struct efx_nic *efx)790{791#ifdef CONFIG_RFS_ACCEL792	struct efx_channel *channel;793 794	efx_for_each_channel(channel, efx) {795		cancel_delayed_work_sync(&channel->filter_work);796		kfree(channel->rps_flow_id);797		channel->rps_flow_id = NULL;798	}799#endif800	down_write(&efx->filter_sem);801	efx->type->filter_table_remove(efx);802	up_write(&efx->filter_sem);803}804 805#ifdef CONFIG_RFS_ACCEL806 807static void efx_filter_rfs_work(struct work_struct *data)808{809	struct efx_async_filter_insertion *req = container_of(data, struct efx_async_filter_insertion,810							      work);811	struct efx_nic *efx = netdev_priv(req->net_dev);812	struct efx_channel *channel = efx_get_channel(efx, req->rxq_index);813	int slot_idx = req - efx->rps_slot;814	struct efx_arfs_rule *rule;815	u16 arfs_id = 0;816	int rc;817 818	rc = efx->type->filter_insert(efx, &req->spec, true);819	if (rc >= 0)820		/* Discard 'priority' part of EF10+ filter ID (mcdi_filters) */821		rc %= efx->type->max_rx_ip_filters;822	if (efx->rps_hash_table) {823		spin_lock_bh(&efx->rps_hash_lock);824		rule = efx_siena_rps_hash_find(efx, &req->spec);825		/* The rule might have already gone, if someone else's request826		 * for the same spec was already worked and then expired before827		 * we got around to our work.  In that case we have nothing828		 * tying us to an arfs_id, meaning that as soon as the filter829		 * is considered for expiry it will be removed.830		 */831		if (rule) {832			if (rc < 0)833				rule->filter_id = EFX_ARFS_FILTER_ID_ERROR;834			else835				rule->filter_id = rc;836			arfs_id = rule->arfs_id;837		}838		spin_unlock_bh(&efx->rps_hash_lock);839	}840	if (rc >= 0) {841		/* Remember this so we can check whether to expire the filter842		 * later.843		 */844		mutex_lock(&efx->rps_mutex);845		if (channel->rps_flow_id[rc] == RPS_FLOW_ID_INVALID)846			channel->rfs_filter_count++;847		channel->rps_flow_id[rc] = req->flow_id;848		mutex_unlock(&efx->rps_mutex);849 850		if (req->spec.ether_type == htons(ETH_P_IP))851			netif_info(efx, rx_status, efx->net_dev,852				   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d id %u]\n",853				   (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",854				   req->spec.rem_host, ntohs(req->spec.rem_port),855				   req->spec.loc_host, ntohs(req->spec.loc_port),856				   req->rxq_index, req->flow_id, rc, arfs_id);857		else858			netif_info(efx, rx_status, efx->net_dev,859				   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d id %u]\n",860				   (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",861				   req->spec.rem_host, ntohs(req->spec.rem_port),862				   req->spec.loc_host, ntohs(req->spec.loc_port),863				   req->rxq_index, req->flow_id, rc, arfs_id);864		channel->n_rfs_succeeded++;865	} else {866		if (req->spec.ether_type == htons(ETH_P_IP))867			netif_dbg(efx, rx_status, efx->net_dev,868				  "failed to steer %s %pI4:%u:%pI4:%u to queue %u [flow %u rc %d id %u]\n",869				  (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",870				  req->spec.rem_host, ntohs(req->spec.rem_port),871				  req->spec.loc_host, ntohs(req->spec.loc_port),872				  req->rxq_index, req->flow_id, rc, arfs_id);873		else874			netif_dbg(efx, rx_status, efx->net_dev,875				  "failed to steer %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u rc %d id %u]\n",876				  (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",877				  req->spec.rem_host, ntohs(req->spec.rem_port),878				  req->spec.loc_host, ntohs(req->spec.loc_port),879				  req->rxq_index, req->flow_id, rc, arfs_id);880		channel->n_rfs_failed++;881		/* We're overloading the NIC's filter tables, so let's do a882		 * chunk of extra expiry work.883		 */884		__efx_siena_filter_rfs_expire(channel,885					      min(channel->rfs_filter_count,886						  100u));887	}888 889	/* Release references */890	clear_bit(slot_idx, &efx->rps_slot_map);891	dev_put(req->net_dev);892}893 894int efx_siena_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,895			 u16 rxq_index, u32 flow_id)896{897	struct efx_nic *efx = netdev_priv(net_dev);898	struct efx_async_filter_insertion *req;899	struct efx_arfs_rule *rule;900	struct flow_keys fk;901	int slot_idx;902	bool new;903	int rc;904 905	/* find a free slot */906	for (slot_idx = 0; slot_idx < EFX_RPS_MAX_IN_FLIGHT; slot_idx++)907		if (!test_and_set_bit(slot_idx, &efx->rps_slot_map))908			break;909	if (slot_idx >= EFX_RPS_MAX_IN_FLIGHT)910		return -EBUSY;911 912	if (flow_id == RPS_FLOW_ID_INVALID) {913		rc = -EINVAL;914		goto out_clear;915	}916 917	if (!skb_flow_dissect_flow_keys(skb, &fk, 0)) {918		rc = -EPROTONOSUPPORT;919		goto out_clear;920	}921 922	if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6)) {923		rc = -EPROTONOSUPPORT;924		goto out_clear;925	}926	if (fk.control.flags & FLOW_DIS_IS_FRAGMENT) {927		rc = -EPROTONOSUPPORT;928		goto out_clear;929	}930 931	req = efx->rps_slot + slot_idx;932	efx_filter_init_rx(&req->spec, EFX_FILTER_PRI_HINT,933			   efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,934			   rxq_index);935	req->spec.match_flags =936		EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO |937		EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT |938		EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT;939	req->spec.ether_type = fk.basic.n_proto;940	req->spec.ip_proto = fk.basic.ip_proto;941 942	if (fk.basic.n_proto == htons(ETH_P_IP)) {943		req->spec.rem_host[0] = fk.addrs.v4addrs.src;944		req->spec.loc_host[0] = fk.addrs.v4addrs.dst;945	} else {946		memcpy(req->spec.rem_host, &fk.addrs.v6addrs.src,947		       sizeof(struct in6_addr));948		memcpy(req->spec.loc_host, &fk.addrs.v6addrs.dst,949		       sizeof(struct in6_addr));950	}951 952	req->spec.rem_port = fk.ports.src;953	req->spec.loc_port = fk.ports.dst;954 955	if (efx->rps_hash_table) {956		/* Add it to ARFS hash table */957		spin_lock(&efx->rps_hash_lock);958		rule = efx_rps_hash_add(efx, &req->spec, &new);959		if (!rule) {960			rc = -ENOMEM;961			goto out_unlock;962		}963		if (new)964			rule->arfs_id = efx->rps_next_id++ % RPS_NO_FILTER;965		rc = rule->arfs_id;966		/* Skip if existing or pending filter already does the right thing */967		if (!new && rule->rxq_index == rxq_index &&968		    rule->filter_id >= EFX_ARFS_FILTER_ID_PENDING)969			goto out_unlock;970		rule->rxq_index = rxq_index;971		rule->filter_id = EFX_ARFS_FILTER_ID_PENDING;972		spin_unlock(&efx->rps_hash_lock);973	} else {974		/* Without an ARFS hash table, we just use arfs_id 0 for all975		 * filters.  This means if multiple flows hash to the same976		 * flow_id, all but the most recently touched will be eligible977		 * for expiry.978		 */979		rc = 0;980	}981 982	/* Queue the request */983	dev_hold(req->net_dev = net_dev);984	INIT_WORK(&req->work, efx_filter_rfs_work);985	req->rxq_index = rxq_index;986	req->flow_id = flow_id;987	schedule_work(&req->work);988	return rc;989out_unlock:990	spin_unlock(&efx->rps_hash_lock);991out_clear:992	clear_bit(slot_idx, &efx->rps_slot_map);993	return rc;994}995 996bool __efx_siena_filter_rfs_expire(struct efx_channel *channel,997				   unsigned int quota)998{999	bool (*expire_one)(struct efx_nic *efx, u32 flow_id, unsigned int index);1000	struct efx_nic *efx = channel->efx;1001	unsigned int index, size, start;1002	u32 flow_id;1003 1004	if (!mutex_trylock(&efx->rps_mutex))1005		return false;1006	expire_one = efx->type->filter_rfs_expire_one;1007	index = channel->rfs_expire_index;1008	start = index;1009	size = efx->type->max_rx_ip_filters;1010	while (quota) {1011		flow_id = channel->rps_flow_id[index];1012 1013		if (flow_id != RPS_FLOW_ID_INVALID) {1014			quota--;1015			if (expire_one(efx, flow_id, index)) {1016				netif_info(efx, rx_status, efx->net_dev,1017					   "expired filter %d [channel %u flow %u]\n",1018					   index, channel->channel, flow_id);1019				channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;1020				channel->rfs_filter_count--;1021			}1022		}1023		if (++index == size)1024			index = 0;1025		/* If we were called with a quota that exceeds the total number1026		 * of filters in the table (which shouldn't happen, but could1027		 * if two callers race), ensure that we don't loop forever -1028		 * stop when we've examined every row of the table.1029		 */1030		if (index == start)1031			break;1032	}1033 1034	channel->rfs_expire_index = index;1035	mutex_unlock(&efx->rps_mutex);1036	return true;1037}1038 1039#endif /* CONFIG_RFS_ACCEL */1040