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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 34/* Check the RX page recycle ring for a page that can be reused. */35static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)36{37	struct efx_nic *efx = rx_queue->efx;38	struct efx_rx_page_state *state;39	unsigned int index;40	struct page *page;41 42	if (unlikely(!rx_queue->page_ring))43		return NULL;44	index = rx_queue->page_remove & rx_queue->page_ptr_mask;45	page = rx_queue->page_ring[index];46	if (page == NULL)47		return NULL;48 49	rx_queue->page_ring[index] = NULL;50	/* page_remove cannot exceed page_add. */51	if (rx_queue->page_remove != rx_queue->page_add)52		++rx_queue->page_remove;53 54	/* If page_count is 1 then we hold the only reference to this page. */55	if (page_count(page) == 1) {56		++rx_queue->page_recycle_count;57		return page;58	} else {59		state = page_address(page);60		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,61			       PAGE_SIZE << efx->rx_buffer_order,62			       DMA_FROM_DEVICE);63		put_page(page);64		++rx_queue->page_recycle_failed;65	}66 67	return NULL;68}69 70/* Attempt to recycle the page if there is an RX recycle ring; the page can71 * only be added if this is the final RX buffer, to prevent pages being used in72 * the descriptor ring and appearing in the recycle ring simultaneously.73 */74static void efx_recycle_rx_page(struct efx_channel *channel,75				struct efx_rx_buffer *rx_buf)76{77	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);78	struct efx_nic *efx = rx_queue->efx;79	struct page *page = rx_buf->page;80	unsigned int index;81 82	/* Only recycle the page after processing the final buffer. */83	if (!(rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE))84		return;85 86	index = rx_queue->page_add & rx_queue->page_ptr_mask;87	if (rx_queue->page_ring[index] == NULL) {88		unsigned int read_index = rx_queue->page_remove &89			rx_queue->page_ptr_mask;90 91		/* The next slot in the recycle ring is available, but92		 * increment page_remove if the read pointer currently93		 * points here.94		 */95		if (read_index == index)96			++rx_queue->page_remove;97		rx_queue->page_ring[index] = page;98		++rx_queue->page_add;99		return;100	}101	++rx_queue->page_recycle_full;102	efx_unmap_rx_buffer(efx, rx_buf);103	put_page(rx_buf->page);104}105 106/* Recycle the pages that are used by buffers that have just been received. */107void efx_recycle_rx_pages(struct efx_channel *channel,108			  struct efx_rx_buffer *rx_buf,109			  unsigned int n_frags)110{111	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);112 113	if (unlikely(!rx_queue->page_ring))114		return;115 116	do {117		efx_recycle_rx_page(channel, rx_buf);118		rx_buf = efx_rx_buf_next(rx_queue, rx_buf);119	} while (--n_frags);120}121 122void efx_discard_rx_packet(struct efx_channel *channel,123			   struct efx_rx_buffer *rx_buf,124			   unsigned int n_frags)125{126	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);127 128	efx_recycle_rx_pages(channel, rx_buf, n_frags);129 130	efx_free_rx_buffers(rx_queue, rx_buf, n_frags);131}132 133static void efx_init_rx_recycle_ring(struct efx_rx_queue *rx_queue)134{135	unsigned int bufs_in_recycle_ring, page_ring_size;136	struct efx_nic *efx = rx_queue->efx;137 138	bufs_in_recycle_ring = efx_rx_recycle_ring_size(efx);139	page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /140					    efx->rx_bufs_per_page);141	rx_queue->page_ring = kcalloc(page_ring_size,142				      sizeof(*rx_queue->page_ring), GFP_KERNEL);143	if (!rx_queue->page_ring)144		rx_queue->page_ptr_mask = 0;145	else146		rx_queue->page_ptr_mask = page_ring_size - 1;147}148 149static void efx_fini_rx_recycle_ring(struct efx_rx_queue *rx_queue)150{151	struct efx_nic *efx = rx_queue->efx;152	int i;153 154	if (unlikely(!rx_queue->page_ring))155		return;156 157	/* Unmap and release the pages in the recycle ring. Remove the ring. */158	for (i = 0; i <= rx_queue->page_ptr_mask; i++) {159		struct page *page = rx_queue->page_ring[i];160		struct efx_rx_page_state *state;161 162		if (page == NULL)163			continue;164 165		state = page_address(page);166		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,167			       PAGE_SIZE << efx->rx_buffer_order,168			       DMA_FROM_DEVICE);169		put_page(page);170	}171	kfree(rx_queue->page_ring);172	rx_queue->page_ring = NULL;173}174 175static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,176			       struct efx_rx_buffer *rx_buf)177{178	/* Release the page reference we hold for the buffer. */179	if (rx_buf->page)180		put_page(rx_buf->page);181 182	/* If this is the last buffer in a page, unmap and free it. */183	if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) {184		efx_unmap_rx_buffer(rx_queue->efx, rx_buf);185		efx_free_rx_buffers(rx_queue, rx_buf, 1);186	}187	rx_buf->page = NULL;188}189 190int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)191{192	struct efx_nic *efx = rx_queue->efx;193	unsigned int entries;194	int rc;195 196	/* Create the smallest power-of-two aligned ring */197	entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);198	EFX_WARN_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);199	rx_queue->ptr_mask = entries - 1;200 201	netif_dbg(efx, probe, efx->net_dev,202		  "creating RX queue %d size %#x mask %#x\n",203		  efx_rx_queue_index(rx_queue), efx->rxq_entries,204		  rx_queue->ptr_mask);205 206	/* Allocate RX buffers */207	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),208				   GFP_KERNEL);209	if (!rx_queue->buffer)210		return -ENOMEM;211 212	rc = efx_nic_probe_rx(rx_queue);213	if (rc) {214		kfree(rx_queue->buffer);215		rx_queue->buffer = NULL;216	}217 218	return rc;219}220 221void efx_init_rx_queue(struct efx_rx_queue *rx_queue)222{223	unsigned int max_fill, trigger, max_trigger;224	struct efx_nic *efx = rx_queue->efx;225	int rc = 0;226 227	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,228		  "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));229 230	/* Initialise ptr fields */231	rx_queue->added_count = 0;232	rx_queue->notified_count = 0;233	rx_queue->granted_count = 0;234	rx_queue->removed_count = 0;235	rx_queue->min_fill = -1U;236	efx_init_rx_recycle_ring(rx_queue);237 238	rx_queue->page_remove = 0;239	rx_queue->page_add = rx_queue->page_ptr_mask + 1;240	rx_queue->page_recycle_count = 0;241	rx_queue->page_recycle_failed = 0;242	rx_queue->page_recycle_full = 0;243 244	/* Initialise limit fields */245	max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;246	max_trigger =247		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;248	if (rx_refill_threshold != 0) {249		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;250		if (trigger > max_trigger)251			trigger = max_trigger;252	} else {253		trigger = max_trigger;254	}255 256	rx_queue->max_fill = max_fill;257	rx_queue->fast_fill_trigger = trigger;258	rx_queue->refill_enabled = true;259 260	/* Initialise XDP queue information */261	rc = xdp_rxq_info_reg(&rx_queue->xdp_rxq_info, efx->net_dev,262			      rx_queue->core_index, 0);263 264	if (rc) {265		netif_err(efx, rx_err, efx->net_dev,266			  "Failure to initialise XDP queue information rc=%d\n",267			  rc);268		efx->xdp_rxq_info_failed = true;269	} else {270		rx_queue->xdp_rxq_info_valid = true;271	}272 273	/* Set up RX descriptor ring */274	efx_nic_init_rx(rx_queue);275}276 277void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)278{279	struct efx_rx_buffer *rx_buf;280	int i;281 282	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,283		  "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));284 285	del_timer_sync(&rx_queue->slow_fill);286	if (rx_queue->grant_credits)287		flush_work(&rx_queue->grant_work);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_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 */322void 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_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_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 359void 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_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_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_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue, bool atomic)458{459	struct efx_nic *efx = rx_queue->efx;460	unsigned int fill_level, batch_size;461	int space, rc = 0;462 463	if (!rx_queue->refill_enabled)464		return;465 466	/* Calculate current fill level, and exit if we don't need to fill */467	fill_level = (rx_queue->added_count - rx_queue->removed_count);468	EFX_WARN_ON_ONCE_PARANOID(fill_level > rx_queue->efx->rxq_entries);469	if (fill_level >= rx_queue->fast_fill_trigger)470		goto out;471 472	/* Record minimum fill level */473	if (unlikely(fill_level < rx_queue->min_fill)) {474		if (fill_level)475			rx_queue->min_fill = fill_level;476	}477 478	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;479	space = rx_queue->max_fill - fill_level;480	EFX_WARN_ON_ONCE_PARANOID(space < batch_size);481 482	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,483		   "RX queue %d fast-filling descriptor ring from"484		   " level %d to level %d\n",485		   efx_rx_queue_index(rx_queue), fill_level,486		   rx_queue->max_fill);487 488	do {489		rc = efx_init_rx_buffers(rx_queue, atomic);490		if (unlikely(rc)) {491			/* Ensure that we don't leave the rx queue empty */492			efx_schedule_slow_fill(rx_queue);493			goto out;494		}495	} while ((space -= batch_size) >= batch_size);496 497	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,498		   "RX queue %d fast-filled descriptor ring "499		   "to level %d\n", efx_rx_queue_index(rx_queue),500		   rx_queue->added_count - rx_queue->removed_count);501 502 out:503	if (rx_queue->notified_count != rx_queue->added_count)504		efx_nic_notify_rx_desc(rx_queue);505}506 507/* Pass a received packet up through GRO.  GRO can handle pages508 * regardless of checksum state and skbs with a good checksum.509 */510void511efx_rx_packet_gro(struct efx_channel *channel, struct efx_rx_buffer *rx_buf,512		  unsigned int n_frags, u8 *eh, __wsum csum)513{514	struct napi_struct *napi = &channel->napi_str;515	struct efx_nic *efx = channel->efx;516	struct sk_buff *skb;517 518	skb = napi_get_frags(napi);519	if (unlikely(!skb)) {520		struct efx_rx_queue *rx_queue;521 522		rx_queue = efx_channel_get_rx_queue(channel);523		efx_free_rx_buffers(rx_queue, rx_buf, n_frags);524		return;525	}526 527	if (efx->net_dev->features & NETIF_F_RXHASH &&528	    efx_rx_buf_hash_valid(efx, eh))529		skb_set_hash(skb, efx_rx_buf_hash(efx, eh),530			     PKT_HASH_TYPE_L3);531	if (csum) {532		skb->csum = csum;533		skb->ip_summed = CHECKSUM_COMPLETE;534	} else {535		skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?536				  CHECKSUM_UNNECESSARY : CHECKSUM_NONE);537	}538	skb->csum_level = !!(rx_buf->flags & EFX_RX_PKT_CSUM_LEVEL);539 540	for (;;) {541		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,542				   rx_buf->page, rx_buf->page_offset,543				   rx_buf->len);544		rx_buf->page = NULL;545		skb->len += rx_buf->len;546		if (skb_shinfo(skb)->nr_frags == n_frags)547			break;548 549		rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);550	}551 552	skb->data_len = skb->len;553	skb->truesize += n_frags * efx->rx_buffer_truesize;554 555	skb_record_rx_queue(skb, channel->rx_queue.core_index);556 557	napi_gro_frags(napi);558}559 560struct efx_rss_context_priv *efx_find_rss_context_entry(struct efx_nic *efx,561							u32 id)562{563	struct ethtool_rxfh_context *ctx;564 565	WARN_ON(!mutex_is_locked(&efx->net_dev->ethtool->rss_lock));566 567	ctx = xa_load(&efx->net_dev->ethtool->rss_ctx, id);568	if (!ctx)569		return NULL;570	return ethtool_rxfh_context_priv(ctx);571}572 573void efx_set_default_rx_indir_table(struct efx_nic *efx, u32 *indir)574{575	size_t i;576 577	for (i = 0; i < ARRAY_SIZE(efx->rss_context.rx_indir_table); i++)578		indir[i] = ethtool_rxfh_indir_default(i, efx->rss_spread);579}580 581/**582 * efx_filter_is_mc_recipient - test whether spec is a multicast recipient583 * @spec: Specification to test584 *585 * Return: %true if the specification is a non-drop RX filter that586 * matches a local MAC address I/G bit value of 1 or matches a local587 * IPv4 or IPv6 address value in the respective multicast address588 * range.  Otherwise %false.589 */590bool efx_filter_is_mc_recipient(const struct efx_filter_spec *spec)591{592	if (!(spec->flags & EFX_FILTER_FLAG_RX) ||593	    spec->dmaq_id == EFX_FILTER_RX_DMAQ_ID_DROP)594		return false;595 596	if (spec->match_flags &597	    (EFX_FILTER_MATCH_LOC_MAC | EFX_FILTER_MATCH_LOC_MAC_IG) &&598	    is_multicast_ether_addr(spec->loc_mac))599		return true;600 601	if ((spec->match_flags &602	     (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) ==603	    (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) {604		if (spec->ether_type == htons(ETH_P_IP) &&605		    ipv4_is_multicast(spec->loc_host[0]))606			return true;607		if (spec->ether_type == htons(ETH_P_IPV6) &&608		    ((const u8 *)spec->loc_host)[0] == 0xff)609			return true;610	}611 612	return false;613}614 615bool efx_filter_spec_equal(const struct efx_filter_spec *left,616			   const struct efx_filter_spec *right)617{618	if ((left->match_flags ^ right->match_flags) |619	    ((left->flags ^ right->flags) &620	     (EFX_FILTER_FLAG_RX | EFX_FILTER_FLAG_TX)))621		return false;622 623	return memcmp(&left->vport_id, &right->vport_id,624		      sizeof(struct efx_filter_spec) -625		      offsetof(struct efx_filter_spec, vport_id)) == 0;626}627 628u32 efx_filter_spec_hash(const struct efx_filter_spec *spec)629{630	BUILD_BUG_ON(offsetof(struct efx_filter_spec, vport_id) & 3);631	return jhash2((const u32 *)&spec->vport_id,632		      (sizeof(struct efx_filter_spec) -633		       offsetof(struct efx_filter_spec, vport_id)) / 4,634		      0);635}636 637#ifdef CONFIG_RFS_ACCEL638bool efx_rps_check_rule(struct efx_arfs_rule *rule, unsigned int filter_idx,639			bool *force)640{641	if (rule->filter_id == EFX_ARFS_FILTER_ID_PENDING) {642		/* ARFS is currently updating this entry, leave it */643		return false;644	}645	if (rule->filter_id == EFX_ARFS_FILTER_ID_ERROR) {646		/* ARFS tried and failed to update this, so it's probably out647		 * of date.  Remove the filter and the ARFS rule entry.648		 */649		rule->filter_id = EFX_ARFS_FILTER_ID_REMOVING;650		*force = true;651		return true;652	} else if (WARN_ON(rule->filter_id != filter_idx)) { /* can't happen */653		/* ARFS has moved on, so old filter is not needed.  Since we did654		 * not mark the rule with EFX_ARFS_FILTER_ID_REMOVING, it will655		 * not be removed by efx_rps_hash_del() subsequently.656		 */657		*force = true;658		return true;659	}660	/* Remove it iff ARFS wants to. */661	return true;662}663 664static665struct hlist_head *efx_rps_hash_bucket(struct efx_nic *efx,666				       const struct efx_filter_spec *spec)667{668	u32 hash = efx_filter_spec_hash(spec);669 670	lockdep_assert_held(&efx->rps_hash_lock);671	if (!efx->rps_hash_table)672		return NULL;673	return &efx->rps_hash_table[hash % EFX_ARFS_HASH_TABLE_SIZE];674}675 676struct efx_arfs_rule *efx_rps_hash_find(struct efx_nic *efx,677					const struct efx_filter_spec *spec)678{679	struct efx_arfs_rule *rule;680	struct hlist_head *head;681	struct hlist_node *node;682 683	head = efx_rps_hash_bucket(efx, spec);684	if (!head)685		return NULL;686	hlist_for_each(node, head) {687		rule = container_of(node, struct efx_arfs_rule, node);688		if (efx_filter_spec_equal(spec, &rule->spec))689			return rule;690	}691	return NULL;692}693 694struct efx_arfs_rule *efx_rps_hash_add(struct efx_nic *efx,695				       const struct efx_filter_spec *spec,696				       bool *new)697{698	struct efx_arfs_rule *rule;699	struct hlist_head *head;700	struct hlist_node *node;701 702	head = efx_rps_hash_bucket(efx, spec);703	if (!head)704		return NULL;705	hlist_for_each(node, head) {706		rule = container_of(node, struct efx_arfs_rule, node);707		if (efx_filter_spec_equal(spec, &rule->spec)) {708			*new = false;709			return rule;710		}711	}712	rule = kmalloc(sizeof(*rule), GFP_ATOMIC);713	*new = true;714	if (rule) {715		memcpy(&rule->spec, spec, sizeof(rule->spec));716		hlist_add_head(&rule->node, head);717	}718	return rule;719}720 721void efx_rps_hash_del(struct efx_nic *efx, const struct efx_filter_spec *spec)722{723	struct efx_arfs_rule *rule;724	struct hlist_head *head;725	struct hlist_node *node;726 727	head = efx_rps_hash_bucket(efx, spec);728	if (WARN_ON(!head))729		return;730	hlist_for_each(node, head) {731		rule = container_of(node, struct efx_arfs_rule, node);732		if (efx_filter_spec_equal(spec, &rule->spec)) {733			/* Someone already reused the entry.  We know that if734			 * this check doesn't fire (i.e. filter_id == REMOVING)735			 * then the REMOVING mark was put there by our caller,736			 * because caller is holding a lock on filter table and737			 * only holders of that lock set REMOVING.738			 */739			if (rule->filter_id != EFX_ARFS_FILTER_ID_REMOVING)740				return;741			hlist_del(node);742			kfree(rule);743			return;744		}745	}746	/* We didn't find it. */747	WARN_ON(1);748}749#endif750 751int efx_probe_filters(struct efx_nic *efx)752{753	int rc;754 755	mutex_lock(&efx->mac_lock);756	rc = efx->type->filter_table_probe(efx);757	if (rc)758		goto out_unlock;759 760#ifdef CONFIG_RFS_ACCEL761	if (efx->type->offload_features & NETIF_F_NTUPLE) {762		struct efx_channel *channel;763		int i, success = 1;764 765		efx_for_each_channel(channel, efx) {766			channel->rps_flow_id =767				kcalloc(efx->type->max_rx_ip_filters,768					sizeof(*channel->rps_flow_id),769					GFP_KERNEL);770			if (!channel->rps_flow_id)771				success = 0;772			else773				for (i = 0;774				     i < efx->type->max_rx_ip_filters;775				     ++i)776					channel->rps_flow_id[i] =777						RPS_FLOW_ID_INVALID;778			channel->rfs_expire_index = 0;779			channel->rfs_filter_count = 0;780		}781 782		if (!success) {783			efx_for_each_channel(channel, efx) {784				kfree(channel->rps_flow_id);785				channel->rps_flow_id = NULL;786			}787			efx->type->filter_table_remove(efx);788			rc = -ENOMEM;789			goto out_unlock;790		}791	}792#endif793out_unlock:794	mutex_unlock(&efx->mac_lock);795	return rc;796}797 798void efx_remove_filters(struct efx_nic *efx)799{800#ifdef CONFIG_RFS_ACCEL801	struct efx_channel *channel;802 803	efx_for_each_channel(channel, efx) {804		cancel_delayed_work_sync(&channel->filter_work);805		kfree(channel->rps_flow_id);806		channel->rps_flow_id = NULL;807	}808#endif809	efx->type->filter_table_remove(efx);810}811 812#ifdef CONFIG_RFS_ACCEL813 814static void efx_filter_rfs_work(struct work_struct *data)815{816	struct efx_async_filter_insertion *req = container_of(data, struct efx_async_filter_insertion,817							      work);818	struct efx_nic *efx = efx_netdev_priv(req->net_dev);819	struct efx_channel *channel = efx_get_channel(efx, req->rxq_index);820	int slot_idx = req - efx->rps_slot;821	struct efx_arfs_rule *rule;822	u16 arfs_id = 0;823	int rc;824 825	rc = efx->type->filter_insert(efx, &req->spec, true);826	if (rc >= 0)827		/* Discard 'priority' part of EF10+ filter ID (mcdi_filters) */828		rc %= efx->type->max_rx_ip_filters;829	if (efx->rps_hash_table) {830		spin_lock_bh(&efx->rps_hash_lock);831		rule = efx_rps_hash_find(efx, &req->spec);832		/* The rule might have already gone, if someone else's request833		 * for the same spec was already worked and then expired before834		 * we got around to our work.  In that case we have nothing835		 * tying us to an arfs_id, meaning that as soon as the filter836		 * is considered for expiry it will be removed.837		 */838		if (rule) {839			if (rc < 0)840				rule->filter_id = EFX_ARFS_FILTER_ID_ERROR;841			else842				rule->filter_id = rc;843			arfs_id = rule->arfs_id;844		}845		spin_unlock_bh(&efx->rps_hash_lock);846	}847	if (rc >= 0) {848		/* Remember this so we can check whether to expire the filter849		 * later.850		 */851		mutex_lock(&efx->rps_mutex);852		if (channel->rps_flow_id[rc] == RPS_FLOW_ID_INVALID)853			channel->rfs_filter_count++;854		channel->rps_flow_id[rc] = req->flow_id;855		mutex_unlock(&efx->rps_mutex);856 857		if (req->spec.ether_type == htons(ETH_P_IP))858			netif_info(efx, rx_status, efx->net_dev,859				   "steering %s %pI4:%u:%pI4:%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		else865			netif_info(efx, rx_status, efx->net_dev,866				   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d id %u]\n",867				   (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",868				   req->spec.rem_host, ntohs(req->spec.rem_port),869				   req->spec.loc_host, ntohs(req->spec.loc_port),870				   req->rxq_index, req->flow_id, rc, arfs_id);871		channel->n_rfs_succeeded++;872	} else {873		if (req->spec.ether_type == htons(ETH_P_IP))874			netif_dbg(efx, rx_status, efx->net_dev,875				  "failed to steer %s %pI4:%u:%pI4:%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		else881			netif_dbg(efx, rx_status, efx->net_dev,882				  "failed to steer %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u rc %d id %u]\n",883				  (req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",884				  req->spec.rem_host, ntohs(req->spec.rem_port),885				  req->spec.loc_host, ntohs(req->spec.loc_port),886				  req->rxq_index, req->flow_id, rc, arfs_id);887		channel->n_rfs_failed++;888		/* We're overloading the NIC's filter tables, so let's do a889		 * chunk of extra expiry work.890		 */891		__efx_filter_rfs_expire(channel, min(channel->rfs_filter_count,892						     100u));893	}894 895	/* Release references */896	clear_bit(slot_idx, &efx->rps_slot_map);897	dev_put(req->net_dev);898}899 900int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,901		   u16 rxq_index, u32 flow_id)902{903	struct efx_nic *efx = efx_netdev_priv(net_dev);904	struct efx_async_filter_insertion *req;905	struct efx_arfs_rule *rule;906	struct flow_keys fk;907	int slot_idx;908	bool new;909	int rc;910 911	/* find a free slot */912	for (slot_idx = 0; slot_idx < EFX_RPS_MAX_IN_FLIGHT; slot_idx++)913		if (!test_and_set_bit(slot_idx, &efx->rps_slot_map))914			break;915	if (slot_idx >= EFX_RPS_MAX_IN_FLIGHT)916		return -EBUSY;917 918	if (flow_id == RPS_FLOW_ID_INVALID) {919		rc = -EINVAL;920		goto out_clear;921	}922 923	if (!skb_flow_dissect_flow_keys(skb, &fk, 0)) {924		rc = -EPROTONOSUPPORT;925		goto out_clear;926	}927 928	if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6)) {929		rc = -EPROTONOSUPPORT;930		goto out_clear;931	}932	if (fk.control.flags & FLOW_DIS_IS_FRAGMENT) {933		rc = -EPROTONOSUPPORT;934		goto out_clear;935	}936 937	req = efx->rps_slot + slot_idx;938	efx_filter_init_rx(&req->spec, EFX_FILTER_PRI_HINT,939			   efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,940			   rxq_index);941	req->spec.match_flags =942		EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO |943		EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT |944		EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT;945	req->spec.ether_type = fk.basic.n_proto;946	req->spec.ip_proto = fk.basic.ip_proto;947 948	if (fk.basic.n_proto == htons(ETH_P_IP)) {949		req->spec.rem_host[0] = fk.addrs.v4addrs.src;950		req->spec.loc_host[0] = fk.addrs.v4addrs.dst;951	} else {952		memcpy(req->spec.rem_host, &fk.addrs.v6addrs.src,953		       sizeof(struct in6_addr));954		memcpy(req->spec.loc_host, &fk.addrs.v6addrs.dst,955		       sizeof(struct in6_addr));956	}957 958	req->spec.rem_port = fk.ports.src;959	req->spec.loc_port = fk.ports.dst;960 961	if (efx->rps_hash_table) {962		/* Add it to ARFS hash table */963		spin_lock(&efx->rps_hash_lock);964		rule = efx_rps_hash_add(efx, &req->spec, &new);965		if (!rule) {966			rc = -ENOMEM;967			goto out_unlock;968		}969		if (new)970			rule->arfs_id = efx->rps_next_id++ % RPS_NO_FILTER;971		rc = rule->arfs_id;972		/* Skip if existing or pending filter already does the right thing */973		if (!new && rule->rxq_index == rxq_index &&974		    rule->filter_id >= EFX_ARFS_FILTER_ID_PENDING)975			goto out_unlock;976		rule->rxq_index = rxq_index;977		rule->filter_id = EFX_ARFS_FILTER_ID_PENDING;978		spin_unlock(&efx->rps_hash_lock);979	} else {980		/* Without an ARFS hash table, we just use arfs_id 0 for all981		 * filters.  This means if multiple flows hash to the same982		 * flow_id, all but the most recently touched will be eligible983		 * for expiry.984		 */985		rc = 0;986	}987 988	/* Queue the request */989	dev_hold(req->net_dev = net_dev);990	INIT_WORK(&req->work, efx_filter_rfs_work);991	req->rxq_index = rxq_index;992	req->flow_id = flow_id;993	schedule_work(&req->work);994	return rc;995out_unlock:996	spin_unlock(&efx->rps_hash_lock);997out_clear:998	clear_bit(slot_idx, &efx->rps_slot_map);999	return rc;1000}1001 1002bool __efx_filter_rfs_expire(struct efx_channel *channel, unsigned int quota)1003{1004	bool (*expire_one)(struct efx_nic *efx, u32 flow_id, unsigned int index);1005	struct efx_nic *efx = channel->efx;1006	unsigned int index, size, start;1007	u32 flow_id;1008 1009	if (!mutex_trylock(&efx->rps_mutex))1010		return false;1011	expire_one = efx->type->filter_rfs_expire_one;1012	index = channel->rfs_expire_index;1013	start = index;1014	size = efx->type->max_rx_ip_filters;1015	while (quota) {1016		flow_id = channel->rps_flow_id[index];1017 1018		if (flow_id != RPS_FLOW_ID_INVALID) {1019			quota--;1020			if (expire_one(efx, flow_id, index)) {1021				netif_info(efx, rx_status, efx->net_dev,1022					   "expired filter %d [channel %u flow %u]\n",1023					   index, channel->channel, flow_id);1024				channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;1025				channel->rfs_filter_count--;1026			}1027		}1028		if (++index == size)1029			index = 0;1030		/* If we were called with a quota that exceeds the total number1031		 * of filters in the table (which shouldn't happen, but could1032		 * if two callers race), ensure that we don't loop forever -1033		 * stop when we've examined every row of the table.1034		 */1035		if (index == start)1036			break;1037	}1038 1039	channel->rfs_expire_index = index;1040	mutex_unlock(&efx->rps_mutex);1041	return true;1042}1043 1044#endif /* CONFIG_RFS_ACCEL */1045