diff options
Diffstat (limited to 'drivers/net/ethernet/sfc/rx.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/rx.c | 981 | 
1 files changed, 981 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c new file mode 100644 index 00000000000..48588ddf81b --- /dev/null +++ b/drivers/net/ethernet/sfc/rx.c @@ -0,0 +1,981 @@ +/**************************************************************************** + * Driver for Solarflare network controllers and boards + * Copyright 2005-2006 Fen Systems Ltd. + * Copyright 2005-2013 Solarflare Communications Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation, incorporated herein by reference. + */ + +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/slab.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/prefetch.h> +#include <linux/moduleparam.h> +#include <linux/iommu.h> +#include <net/ip.h> +#include <net/checksum.h> +#include "net_driver.h" +#include "efx.h" +#include "filter.h" +#include "nic.h" +#include "selftest.h" +#include "workarounds.h" + +/* Preferred number of descriptors to fill at once */ +#define EFX_RX_PREFERRED_BATCH 8U + +/* Number of RX buffers to recycle pages for.  When creating the RX page recycle + * ring, this number is divided by the number of buffers per page to calculate + * the number of pages to store in the RX page recycle ring. + */ +#define EFX_RECYCLE_RING_SIZE_IOMMU 4096 +#define EFX_RECYCLE_RING_SIZE_NOIOMMU (2 * EFX_RX_PREFERRED_BATCH) + +/* Size of buffer allocated for skb header area. */ +#define EFX_SKB_HEADERS  128u + +/* This is the percentage fill level below which new RX descriptors + * will be added to the RX descriptor ring. + */ +static unsigned int rx_refill_threshold; + +/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */ +#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \ +				      EFX_RX_USR_BUF_SIZE) + +/* + * RX maximum head room required. + * + * This must be at least 1 to prevent overflow, plus one packet-worth + * to allow pipelined receives. + */ +#define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS) + +static inline u8 *efx_rx_buf_va(struct efx_rx_buffer *buf) +{ +	return page_address(buf->page) + buf->page_offset; +} + +static inline u32 efx_rx_buf_hash(struct efx_nic *efx, const u8 *eh) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) +	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_hash_offset)); +#else +	const u8 *data = eh + efx->rx_packet_hash_offset; +	return (u32)data[0]	  | +	       (u32)data[1] << 8  | +	       (u32)data[2] << 16 | +	       (u32)data[3] << 24; +#endif +} + +static inline struct efx_rx_buffer * +efx_rx_buf_next(struct efx_rx_queue *rx_queue, struct efx_rx_buffer *rx_buf) +{ +	if (unlikely(rx_buf == efx_rx_buffer(rx_queue, rx_queue->ptr_mask))) +		return efx_rx_buffer(rx_queue, 0); +	else +		return rx_buf + 1; +} + +static inline void efx_sync_rx_buffer(struct efx_nic *efx, +				      struct efx_rx_buffer *rx_buf, +				      unsigned int len) +{ +	dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len, +				DMA_FROM_DEVICE); +} + +void efx_rx_config_page_split(struct efx_nic *efx) +{ +	efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align, +				      EFX_RX_BUF_ALIGNMENT); +	efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 : +		((PAGE_SIZE - sizeof(struct efx_rx_page_state)) / +		 efx->rx_page_buf_step); +	efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) / +		efx->rx_bufs_per_page; +	efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH, +					       efx->rx_bufs_per_page); +} + +/* Check the RX page recycle ring for a page that can be reused. */ +static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue) +{ +	struct efx_nic *efx = rx_queue->efx; +	struct page *page; +	struct efx_rx_page_state *state; +	unsigned index; + +	index = rx_queue->page_remove & rx_queue->page_ptr_mask; +	page = rx_queue->page_ring[index]; +	if (page == NULL) +		return NULL; + +	rx_queue->page_ring[index] = NULL; +	/* page_remove cannot exceed page_add. */ +	if (rx_queue->page_remove != rx_queue->page_add) +		++rx_queue->page_remove; + +	/* If page_count is 1 then we hold the only reference to this page. */ +	if (page_count(page) == 1) { +		++rx_queue->page_recycle_count; +		return page; +	} else { +		state = page_address(page); +		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, +			       PAGE_SIZE << efx->rx_buffer_order, +			       DMA_FROM_DEVICE); +		put_page(page); +		++rx_queue->page_recycle_failed; +	} + +	return NULL; +} + +/** + * efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers + * + * @rx_queue:		Efx RX queue + * + * This allocates a batch of pages, maps them for DMA, and populates + * struct efx_rx_buffers for each one. Return a negative error code or + * 0 on success. If a single page can be used for multiple buffers, + * then the page will either be inserted fully, or not at all. + */ +static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue, bool atomic) +{ +	struct efx_nic *efx = rx_queue->efx; +	struct efx_rx_buffer *rx_buf; +	struct page *page; +	unsigned int page_offset; +	struct efx_rx_page_state *state; +	dma_addr_t dma_addr; +	unsigned index, count; + +	count = 0; +	do { +		page = efx_reuse_page(rx_queue); +		if (page == NULL) { +			page = alloc_pages(__GFP_COLD | __GFP_COMP | +					   (atomic ? GFP_ATOMIC : GFP_KERNEL), +					   efx->rx_buffer_order); +			if (unlikely(page == NULL)) +				return -ENOMEM; +			dma_addr = +				dma_map_page(&efx->pci_dev->dev, page, 0, +					     PAGE_SIZE << efx->rx_buffer_order, +					     DMA_FROM_DEVICE); +			if (unlikely(dma_mapping_error(&efx->pci_dev->dev, +						       dma_addr))) { +				__free_pages(page, efx->rx_buffer_order); +				return -EIO; +			} +			state = page_address(page); +			state->dma_addr = dma_addr; +		} else { +			state = page_address(page); +			dma_addr = state->dma_addr; +		} + +		dma_addr += sizeof(struct efx_rx_page_state); +		page_offset = sizeof(struct efx_rx_page_state); + +		do { +			index = rx_queue->added_count & rx_queue->ptr_mask; +			rx_buf = efx_rx_buffer(rx_queue, index); +			rx_buf->dma_addr = dma_addr + efx->rx_ip_align; +			rx_buf->page = page; +			rx_buf->page_offset = page_offset + efx->rx_ip_align; +			rx_buf->len = efx->rx_dma_len; +			rx_buf->flags = 0; +			++rx_queue->added_count; +			get_page(page); +			dma_addr += efx->rx_page_buf_step; +			page_offset += efx->rx_page_buf_step; +		} while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE); + +		rx_buf->flags = EFX_RX_BUF_LAST_IN_PAGE; +	} while (++count < efx->rx_pages_per_batch); + +	return 0; +} + +/* Unmap a DMA-mapped page.  This function is only called for the final RX + * buffer in a page. + */ +static void efx_unmap_rx_buffer(struct efx_nic *efx, +				struct efx_rx_buffer *rx_buf) +{ +	struct page *page = rx_buf->page; + +	if (page) { +		struct efx_rx_page_state *state = page_address(page); +		dma_unmap_page(&efx->pci_dev->dev, +			       state->dma_addr, +			       PAGE_SIZE << efx->rx_buffer_order, +			       DMA_FROM_DEVICE); +	} +} + +static void efx_free_rx_buffer(struct efx_rx_buffer *rx_buf) +{ +	if (rx_buf->page) { +		put_page(rx_buf->page); +		rx_buf->page = NULL; +	} +} + +/* Attempt to recycle the page if there is an RX recycle ring; the page can + * only be added if this is the final RX buffer, to prevent pages being used in + * the descriptor ring and appearing in the recycle ring simultaneously. + */ +static void efx_recycle_rx_page(struct efx_channel *channel, +				struct efx_rx_buffer *rx_buf) +{ +	struct page *page = rx_buf->page; +	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); +	struct efx_nic *efx = rx_queue->efx; +	unsigned index; + +	/* Only recycle the page after processing the final buffer. */ +	if (!(rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE)) +		return; + +	index = rx_queue->page_add & rx_queue->page_ptr_mask; +	if (rx_queue->page_ring[index] == NULL) { +		unsigned read_index = rx_queue->page_remove & +			rx_queue->page_ptr_mask; + +		/* The next slot in the recycle ring is available, but +		 * increment page_remove if the read pointer currently +		 * points here. +		 */ +		if (read_index == index) +			++rx_queue->page_remove; +		rx_queue->page_ring[index] = page; +		++rx_queue->page_add; +		return; +	} +	++rx_queue->page_recycle_full; +	efx_unmap_rx_buffer(efx, rx_buf); +	put_page(rx_buf->page); +} + +static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue, +			       struct efx_rx_buffer *rx_buf) +{ +	/* Release the page reference we hold for the buffer. */ +	if (rx_buf->page) +		put_page(rx_buf->page); + +	/* If this is the last buffer in a page, unmap and free it. */ +	if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) { +		efx_unmap_rx_buffer(rx_queue->efx, rx_buf); +		efx_free_rx_buffer(rx_buf); +	} +	rx_buf->page = NULL; +} + +/* Recycle the pages that are used by buffers that have just been received. */ +static void efx_recycle_rx_pages(struct efx_channel *channel, +				 struct efx_rx_buffer *rx_buf, +				 unsigned int n_frags) +{ +	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); + +	do { +		efx_recycle_rx_page(channel, rx_buf); +		rx_buf = efx_rx_buf_next(rx_queue, rx_buf); +	} while (--n_frags); +} + +static void efx_discard_rx_packet(struct efx_channel *channel, +				  struct efx_rx_buffer *rx_buf, +				  unsigned int n_frags) +{ +	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); + +	efx_recycle_rx_pages(channel, rx_buf, n_frags); + +	do { +		efx_free_rx_buffer(rx_buf); +		rx_buf = efx_rx_buf_next(rx_queue, rx_buf); +	} while (--n_frags); +} + +/** + * efx_fast_push_rx_descriptors - push new RX descriptors quickly + * @rx_queue:		RX descriptor queue + * + * This will aim to fill the RX descriptor queue up to + * @rx_queue->@max_fill. If there is insufficient atomic + * memory to do so, a slow fill will be scheduled. + * + * The caller must provide serialisation (none is used here). In practise, + * this means this function must run from the NAPI handler, or be called + * when NAPI is disabled. + */ +void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue, bool atomic) +{ +	struct efx_nic *efx = rx_queue->efx; +	unsigned int fill_level, batch_size; +	int space, rc = 0; + +	if (!rx_queue->refill_enabled) +		return; + +	/* Calculate current fill level, and exit if we don't need to fill */ +	fill_level = (rx_queue->added_count - rx_queue->removed_count); +	EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries); +	if (fill_level >= rx_queue->fast_fill_trigger) +		goto out; + +	/* Record minimum fill level */ +	if (unlikely(fill_level < rx_queue->min_fill)) { +		if (fill_level) +			rx_queue->min_fill = fill_level; +	} + +	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page; +	space = rx_queue->max_fill - fill_level; +	EFX_BUG_ON_PARANOID(space < batch_size); + +	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, +		   "RX queue %d fast-filling descriptor ring from" +		   " level %d to level %d\n", +		   efx_rx_queue_index(rx_queue), fill_level, +		   rx_queue->max_fill); + + +	do { +		rc = efx_init_rx_buffers(rx_queue, atomic); +		if (unlikely(rc)) { +			/* Ensure that we don't leave the rx queue empty */ +			if (rx_queue->added_count == rx_queue->removed_count) +				efx_schedule_slow_fill(rx_queue); +			goto out; +		} +	} while ((space -= batch_size) >= batch_size); + +	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, +		   "RX queue %d fast-filled descriptor ring " +		   "to level %d\n", efx_rx_queue_index(rx_queue), +		   rx_queue->added_count - rx_queue->removed_count); + + out: +	if (rx_queue->notified_count != rx_queue->added_count) +		efx_nic_notify_rx_desc(rx_queue); +} + +void efx_rx_slow_fill(unsigned long context) +{ +	struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context; + +	/* Post an event to cause NAPI to run and refill the queue */ +	efx_nic_generate_fill_event(rx_queue); +	++rx_queue->slow_fill_count; +} + +static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue, +				     struct efx_rx_buffer *rx_buf, +				     int len) +{ +	struct efx_nic *efx = rx_queue->efx; +	unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding; + +	if (likely(len <= max_len)) +		return; + +	/* The packet must be discarded, but this is only a fatal error +	 * if the caller indicated it was +	 */ +	rx_buf->flags |= EFX_RX_PKT_DISCARD; + +	if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) { +		if (net_ratelimit()) +			netif_err(efx, rx_err, efx->net_dev, +				  " RX queue %d seriously overlength " +				  "RX event (0x%x > 0x%x+0x%x). Leaking\n", +				  efx_rx_queue_index(rx_queue), len, max_len, +				  efx->type->rx_buffer_padding); +		efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY); +	} else { +		if (net_ratelimit()) +			netif_err(efx, rx_err, efx->net_dev, +				  " RX queue %d overlength RX event " +				  "(0x%x > 0x%x)\n", +				  efx_rx_queue_index(rx_queue), len, max_len); +	} + +	efx_rx_queue_channel(rx_queue)->n_rx_overlength++; +} + +/* Pass a received packet up through GRO.  GRO can handle pages + * regardless of checksum state and skbs with a good checksum. + */ +static void +efx_rx_packet_gro(struct efx_channel *channel, struct efx_rx_buffer *rx_buf, +		  unsigned int n_frags, u8 *eh) +{ +	struct napi_struct *napi = &channel->napi_str; +	gro_result_t gro_result; +	struct efx_nic *efx = channel->efx; +	struct sk_buff *skb; + +	skb = napi_get_frags(napi); +	if (unlikely(!skb)) { +		while (n_frags--) { +			put_page(rx_buf->page); +			rx_buf->page = NULL; +			rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); +		} +		return; +	} + +	if (efx->net_dev->features & NETIF_F_RXHASH) +		skb_set_hash(skb, efx_rx_buf_hash(efx, eh), +			     PKT_HASH_TYPE_L3); +	skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ? +			  CHECKSUM_UNNECESSARY : CHECKSUM_NONE); + +	for (;;) { +		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, +				   rx_buf->page, rx_buf->page_offset, +				   rx_buf->len); +		rx_buf->page = NULL; +		skb->len += rx_buf->len; +		if (skb_shinfo(skb)->nr_frags == n_frags) +			break; + +		rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); +	} + +	skb->data_len = skb->len; +	skb->truesize += n_frags * efx->rx_buffer_truesize; + +	skb_record_rx_queue(skb, channel->rx_queue.core_index); + +	gro_result = napi_gro_frags(napi); +	if (gro_result != GRO_DROP) +		channel->irq_mod_score += 2; +} + +/* Allocate and construct an SKB around page fragments */ +static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel, +				     struct efx_rx_buffer *rx_buf, +				     unsigned int n_frags, +				     u8 *eh, int hdr_len) +{ +	struct efx_nic *efx = channel->efx; +	struct sk_buff *skb; + +	/* Allocate an SKB to store the headers */ +	skb = netdev_alloc_skb(efx->net_dev, +			       efx->rx_ip_align + efx->rx_prefix_size + +			       hdr_len); +	if (unlikely(skb == NULL)) +		return NULL; + +	EFX_BUG_ON_PARANOID(rx_buf->len < hdr_len); + +	memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size, +	       efx->rx_prefix_size + hdr_len); +	skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size); +	__skb_put(skb, hdr_len); + +	/* Append the remaining page(s) onto the frag list */ +	if (rx_buf->len > hdr_len) { +		rx_buf->page_offset += hdr_len; +		rx_buf->len -= hdr_len; + +		for (;;) { +			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, +					   rx_buf->page, rx_buf->page_offset, +					   rx_buf->len); +			rx_buf->page = NULL; +			skb->len += rx_buf->len; +			skb->data_len += rx_buf->len; +			if (skb_shinfo(skb)->nr_frags == n_frags) +				break; + +			rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); +		} +	} else { +		__free_pages(rx_buf->page, efx->rx_buffer_order); +		rx_buf->page = NULL; +		n_frags = 0; +	} + +	skb->truesize += n_frags * efx->rx_buffer_truesize; + +	/* Move past the ethernet header */ +	skb->protocol = eth_type_trans(skb, efx->net_dev); + +	return skb; +} + +void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index, +		   unsigned int n_frags, unsigned int len, u16 flags) +{ +	struct efx_nic *efx = rx_queue->efx; +	struct efx_channel *channel = efx_rx_queue_channel(rx_queue); +	struct efx_rx_buffer *rx_buf; + +	rx_buf = efx_rx_buffer(rx_queue, index); +	rx_buf->flags |= flags; + +	/* Validate the number of fragments and completed length */ +	if (n_frags == 1) { +		if (!(flags & EFX_RX_PKT_PREFIX_LEN)) +			efx_rx_packet__check_len(rx_queue, rx_buf, len); +	} else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) || +		   unlikely(len <= (n_frags - 1) * efx->rx_dma_len) || +		   unlikely(len > n_frags * efx->rx_dma_len) || +		   unlikely(!efx->rx_scatter)) { +		/* If this isn't an explicit discard request, either +		 * the hardware or the driver is broken. +		 */ +		WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD)); +		rx_buf->flags |= EFX_RX_PKT_DISCARD; +	} + +	netif_vdbg(efx, rx_status, efx->net_dev, +		   "RX queue %d received ids %x-%x len %d %s%s\n", +		   efx_rx_queue_index(rx_queue), index, +		   (index + n_frags - 1) & rx_queue->ptr_mask, len, +		   (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "", +		   (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : ""); + +	/* Discard packet, if instructed to do so.  Process the +	 * previous receive first. +	 */ +	if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) { +		efx_rx_flush_packet(channel); +		efx_discard_rx_packet(channel, rx_buf, n_frags); +		return; +	} + +	if (n_frags == 1 && !(flags & EFX_RX_PKT_PREFIX_LEN)) +		rx_buf->len = len; + +	/* Release and/or sync the DMA mapping - assumes all RX buffers +	 * consumed in-order per RX queue. +	 */ +	efx_sync_rx_buffer(efx, rx_buf, rx_buf->len); + +	/* Prefetch nice and early so data will (hopefully) be in cache by +	 * the time we look at it. +	 */ +	prefetch(efx_rx_buf_va(rx_buf)); + +	rx_buf->page_offset += efx->rx_prefix_size; +	rx_buf->len -= efx->rx_prefix_size; + +	if (n_frags > 1) { +		/* Release/sync DMA mapping for additional fragments. +		 * Fix length for last fragment. +		 */ +		unsigned int tail_frags = n_frags - 1; + +		for (;;) { +			rx_buf = efx_rx_buf_next(rx_queue, rx_buf); +			if (--tail_frags == 0) +				break; +			efx_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len); +		} +		rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len; +		efx_sync_rx_buffer(efx, rx_buf, rx_buf->len); +	} + +	/* All fragments have been DMA-synced, so recycle pages. */ +	rx_buf = efx_rx_buffer(rx_queue, index); +	efx_recycle_rx_pages(channel, rx_buf, n_frags); + +	/* Pipeline receives so that we give time for packet headers to be +	 * prefetched into cache. +	 */ +	efx_rx_flush_packet(channel); +	channel->rx_pkt_n_frags = n_frags; +	channel->rx_pkt_index = index; +} + +static void efx_rx_deliver(struct efx_channel *channel, u8 *eh, +			   struct efx_rx_buffer *rx_buf, +			   unsigned int n_frags) +{ +	struct sk_buff *skb; +	u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS); + +	skb = efx_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len); +	if (unlikely(skb == NULL)) { +		efx_free_rx_buffer(rx_buf); +		return; +	} +	skb_record_rx_queue(skb, channel->rx_queue.core_index); + +	/* Set the SKB flags */ +	skb_checksum_none_assert(skb); +	if (likely(rx_buf->flags & EFX_RX_PKT_CSUMMED)) +		skb->ip_summed = CHECKSUM_UNNECESSARY; + +	efx_rx_skb_attach_timestamp(channel, skb); + +	if (channel->type->receive_skb) +		if (channel->type->receive_skb(channel, skb)) +			return; + +	/* Pass the packet up */ +	netif_receive_skb(skb); +} + +/* Handle a received packet.  Second half: Touches packet payload. */ +void __efx_rx_packet(struct efx_channel *channel) +{ +	struct efx_nic *efx = channel->efx; +	struct efx_rx_buffer *rx_buf = +		efx_rx_buffer(&channel->rx_queue, channel->rx_pkt_index); +	u8 *eh = efx_rx_buf_va(rx_buf); + +	/* Read length from the prefix if necessary.  This already +	 * excludes the length of the prefix itself. +	 */ +	if (rx_buf->flags & EFX_RX_PKT_PREFIX_LEN) +		rx_buf->len = le16_to_cpup((__le16 *) +					   (eh + efx->rx_packet_len_offset)); + +	/* If we're in loopback test, then pass the packet directly to the +	 * loopback layer, and free the rx_buf here +	 */ +	if (unlikely(efx->loopback_selftest)) { +		efx_loopback_rx_packet(efx, eh, rx_buf->len); +		efx_free_rx_buffer(rx_buf); +		goto out; +	} + +	if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM))) +		rx_buf->flags &= ~EFX_RX_PKT_CSUMMED; + +	if ((rx_buf->flags & EFX_RX_PKT_TCP) && !channel->type->receive_skb) +		efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh); +	else +		efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags); +out: +	channel->rx_pkt_n_frags = 0; +} + +int efx_probe_rx_queue(struct efx_rx_queue *rx_queue) +{ +	struct efx_nic *efx = rx_queue->efx; +	unsigned int entries; +	int rc; + +	/* Create the smallest power-of-two aligned ring */ +	entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE); +	EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE); +	rx_queue->ptr_mask = entries - 1; + +	netif_dbg(efx, probe, efx->net_dev, +		  "creating RX queue %d size %#x mask %#x\n", +		  efx_rx_queue_index(rx_queue), efx->rxq_entries, +		  rx_queue->ptr_mask); + +	/* Allocate RX buffers */ +	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer), +				   GFP_KERNEL); +	if (!rx_queue->buffer) +		return -ENOMEM; + +	rc = efx_nic_probe_rx(rx_queue); +	if (rc) { +		kfree(rx_queue->buffer); +		rx_queue->buffer = NULL; +	} + +	return rc; +} + +static void efx_init_rx_recycle_ring(struct efx_nic *efx, +				     struct efx_rx_queue *rx_queue) +{ +	unsigned int bufs_in_recycle_ring, page_ring_size; + +	/* Set the RX recycle ring size */ +#ifdef CONFIG_PPC64 +	bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU; +#else +	if (iommu_present(&pci_bus_type)) +		bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU; +	else +		bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_NOIOMMU; +#endif /* CONFIG_PPC64 */ + +	page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring / +					    efx->rx_bufs_per_page); +	rx_queue->page_ring = kcalloc(page_ring_size, +				      sizeof(*rx_queue->page_ring), GFP_KERNEL); +	rx_queue->page_ptr_mask = page_ring_size - 1; +} + +void efx_init_rx_queue(struct efx_rx_queue *rx_queue) +{ +	struct efx_nic *efx = rx_queue->efx; +	unsigned int max_fill, trigger, max_trigger; + +	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, +		  "initialising RX queue %d\n", efx_rx_queue_index(rx_queue)); + +	/* Initialise ptr fields */ +	rx_queue->added_count = 0; +	rx_queue->notified_count = 0; +	rx_queue->removed_count = 0; +	rx_queue->min_fill = -1U; +	efx_init_rx_recycle_ring(efx, rx_queue); + +	rx_queue->page_remove = 0; +	rx_queue->page_add = rx_queue->page_ptr_mask + 1; +	rx_queue->page_recycle_count = 0; +	rx_queue->page_recycle_failed = 0; +	rx_queue->page_recycle_full = 0; + +	/* Initialise limit fields */ +	max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM; +	max_trigger = +		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page; +	if (rx_refill_threshold != 0) { +		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U; +		if (trigger > max_trigger) +			trigger = max_trigger; +	} else { +		trigger = max_trigger; +	} + +	rx_queue->max_fill = max_fill; +	rx_queue->fast_fill_trigger = trigger; +	rx_queue->refill_enabled = true; + +	/* Set up RX descriptor ring */ +	efx_nic_init_rx(rx_queue); +} + +void efx_fini_rx_queue(struct efx_rx_queue *rx_queue) +{ +	int i; +	struct efx_nic *efx = rx_queue->efx; +	struct efx_rx_buffer *rx_buf; + +	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, +		  "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue)); + +	del_timer_sync(&rx_queue->slow_fill); + +	/* Release RX buffers from the current read ptr to the write ptr */ +	if (rx_queue->buffer) { +		for (i = rx_queue->removed_count; i < rx_queue->added_count; +		     i++) { +			unsigned index = i & rx_queue->ptr_mask; +			rx_buf = efx_rx_buffer(rx_queue, index); +			efx_fini_rx_buffer(rx_queue, rx_buf); +		} +	} + +	/* Unmap and release the pages in the recycle ring. Remove the ring. */ +	for (i = 0; i <= rx_queue->page_ptr_mask; i++) { +		struct page *page = rx_queue->page_ring[i]; +		struct efx_rx_page_state *state; + +		if (page == NULL) +			continue; + +		state = page_address(page); +		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, +			       PAGE_SIZE << efx->rx_buffer_order, +			       DMA_FROM_DEVICE); +		put_page(page); +	} +	kfree(rx_queue->page_ring); +	rx_queue->page_ring = NULL; +} + +void efx_remove_rx_queue(struct efx_rx_queue *rx_queue) +{ +	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, +		  "destroying RX queue %d\n", efx_rx_queue_index(rx_queue)); + +	efx_nic_remove_rx(rx_queue); + +	kfree(rx_queue->buffer); +	rx_queue->buffer = NULL; +} + + +module_param(rx_refill_threshold, uint, 0444); +MODULE_PARM_DESC(rx_refill_threshold, +		 "RX descriptor ring refill threshold (%)"); + +#ifdef CONFIG_RFS_ACCEL + +int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb, +		   u16 rxq_index, u32 flow_id) +{ +	struct efx_nic *efx = netdev_priv(net_dev); +	struct efx_channel *channel; +	struct efx_filter_spec spec; +	const __be16 *ports; +	__be16 ether_type; +	int nhoff; +	int rc; + +	/* The core RPS/RFS code has already parsed and validated +	 * VLAN, IP and transport headers.  We assume they are in the +	 * header area. +	 */ + +	if (skb->protocol == htons(ETH_P_8021Q)) { +		const struct vlan_hdr *vh = +			(const struct vlan_hdr *)skb->data; + +		/* We can't filter on the IP 5-tuple and the vlan +		 * together, so just strip the vlan header and filter +		 * on the IP part. +		 */ +		EFX_BUG_ON_PARANOID(skb_headlen(skb) < sizeof(*vh)); +		ether_type = vh->h_vlan_encapsulated_proto; +		nhoff = sizeof(struct vlan_hdr); +	} else { +		ether_type = skb->protocol; +		nhoff = 0; +	} + +	if (ether_type != htons(ETH_P_IP) && ether_type != htons(ETH_P_IPV6)) +		return -EPROTONOSUPPORT; + +	efx_filter_init_rx(&spec, EFX_FILTER_PRI_HINT, +			   efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0, +			   rxq_index); +	spec.match_flags = +		EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO | +		EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT | +		EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT; +	spec.ether_type = ether_type; + +	if (ether_type == htons(ETH_P_IP)) { +		const struct iphdr *ip = +			(const struct iphdr *)(skb->data + nhoff); + +		EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + sizeof(*ip)); +		if (ip_is_fragment(ip)) +			return -EPROTONOSUPPORT; +		spec.ip_proto = ip->protocol; +		spec.rem_host[0] = ip->saddr; +		spec.loc_host[0] = ip->daddr; +		EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + 4 * ip->ihl + 4); +		ports = (const __be16 *)(skb->data + nhoff + 4 * ip->ihl); +	} else { +		const struct ipv6hdr *ip6 = +			(const struct ipv6hdr *)(skb->data + nhoff); + +		EFX_BUG_ON_PARANOID(skb_headlen(skb) < +				    nhoff + sizeof(*ip6) + 4); +		spec.ip_proto = ip6->nexthdr; +		memcpy(spec.rem_host, &ip6->saddr, sizeof(ip6->saddr)); +		memcpy(spec.loc_host, &ip6->daddr, sizeof(ip6->daddr)); +		ports = (const __be16 *)(ip6 + 1); +	} + +	spec.rem_port = ports[0]; +	spec.loc_port = ports[1]; + +	rc = efx->type->filter_rfs_insert(efx, &spec); +	if (rc < 0) +		return rc; + +	/* Remember this so we can check whether to expire the filter later */ +	efx->rps_flow_id[rc] = flow_id; +	channel = efx_get_channel(efx, skb_get_rx_queue(skb)); +	++channel->rfs_filters_added; + +	if (ether_type == htons(ETH_P_IP)) +		netif_info(efx, rx_status, efx->net_dev, +			   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n", +			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP", +			   spec.rem_host, ntohs(ports[0]), spec.loc_host, +			   ntohs(ports[1]), rxq_index, flow_id, rc); +	else +		netif_info(efx, rx_status, efx->net_dev, +			   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n", +			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP", +			   spec.rem_host, ntohs(ports[0]), spec.loc_host, +			   ntohs(ports[1]), rxq_index, flow_id, rc); + +	return rc; +} + +bool __efx_filter_rfs_expire(struct efx_nic *efx, unsigned int quota) +{ +	bool (*expire_one)(struct efx_nic *efx, u32 flow_id, unsigned int index); +	unsigned int index, size; +	u32 flow_id; + +	if (!spin_trylock_bh(&efx->filter_lock)) +		return false; + +	expire_one = efx->type->filter_rfs_expire_one; +	index = efx->rps_expire_index; +	size = efx->type->max_rx_ip_filters; +	while (quota--) { +		flow_id = efx->rps_flow_id[index]; +		if (expire_one(efx, flow_id, index)) +			netif_info(efx, rx_status, efx->net_dev, +				   "expired filter %d [flow %u]\n", +				   index, flow_id); +		if (++index == size) +			index = 0; +	} +	efx->rps_expire_index = index; + +	spin_unlock_bh(&efx->filter_lock); +	return true; +} + +#endif /* CONFIG_RFS_ACCEL */ + +/** + * efx_filter_is_mc_recipient - test whether spec is a multicast recipient + * @spec: Specification to test + * + * Return: %true if the specification is a non-drop RX filter that + * matches a local MAC address I/G bit value of 1 or matches a local + * IPv4 or IPv6 address value in the respective multicast address + * range.  Otherwise %false. + */ +bool efx_filter_is_mc_recipient(const struct efx_filter_spec *spec) +{ +	if (!(spec->flags & EFX_FILTER_FLAG_RX) || +	    spec->dmaq_id == EFX_FILTER_RX_DMAQ_ID_DROP) +		return false; + +	if (spec->match_flags & +	    (EFX_FILTER_MATCH_LOC_MAC | EFX_FILTER_MATCH_LOC_MAC_IG) && +	    is_multicast_ether_addr(spec->loc_mac)) +		return true; + +	if ((spec->match_flags & +	     (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) == +	    (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) { +		if (spec->ether_type == htons(ETH_P_IP) && +		    ipv4_is_multicast(spec->loc_host[0])) +			return true; +		if (spec->ether_type == htons(ETH_P_IPV6) && +		    ((const u8 *)spec->loc_host)[0] == 0xff) +			return true; +	} + +	return false; +}  | 
