From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/net/ethernet/sfc/rx.c | 399 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 399 insertions(+) create mode 100644 drivers/net/ethernet/sfc/rx.c (limited to 'drivers/net/ethernet/sfc/rx.c') diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c new file mode 100644 index 000000000..2375cef57 --- /dev/null +++ b/drivers/net/ethernet/sfc/rx.c @@ -0,0 +1,399 @@ +// SPDX-License-Identifier: GPL-2.0-only +/**************************************************************************** + * Driver for Solarflare network controllers and boards + * Copyright 2005-2006 Fen Systems Ltd. + * Copyright 2005-2013 Solarflare Communications Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "net_driver.h" +#include "efx.h" +#include "rx_common.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 + +/* Maximum rx prefix used by any architecture. */ +#define EFX_MAX_RX_PREFIX_SIZE 16 + +/* Size of buffer allocated for skb header area. */ +#define EFX_SKB_HEADERS 128u + +/* 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) + +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 (net_ratelimit()) + netif_err(efx, rx_err, efx->net_dev, + "RX queue %d overlength RX event (%#x > %#x)\n", + efx_rx_queue_index(rx_queue), len, max_len); + + efx_rx_queue_channel(rx_queue)->n_rx_overlength++; +} + +/* 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)) { + atomic_inc(&efx->n_rx_noskb_drops); + return NULL; + } + + EFX_WARN_ON_ONCE_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_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, + rx_buf->page, rx_buf->page_offset, + rx_buf->len, efx->rx_buffer_truesize); + rx_buf->page = NULL; + + 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; + } + + /* Move past the ethernet header */ + skb->protocol = eth_type_trans(skb, efx->net_dev); + + skb_mark_napi_id(skb, &channel->napi_str); + + 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_queue->rx_packets++; + + 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)) { + struct efx_rx_queue *rx_queue; + + rx_queue = efx_channel_get_rx_queue(channel); + efx_free_rx_buffers(rx_queue, rx_buf, n_frags); + 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; + skb->csum_level = !!(rx_buf->flags & EFX_RX_PKT_CSUM_LEVEL); + } + + efx_rx_skb_attach_timestamp(channel, skb); + + if (channel->type->receive_skb) + if (channel->type->receive_skb(channel, skb)) + return; + + /* Pass the packet up */ + if (channel->rx_list != NULL) + /* Add to list, will pass up later */ + list_add_tail(&skb->list, channel->rx_list); + else + /* No list, so pass it up now */ + netif_receive_skb(skb); +} + +/** efx_do_xdp: perform XDP processing on a received packet + * + * Returns true if packet should still be delivered. + */ +static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel, + struct efx_rx_buffer *rx_buf, u8 **ehp) +{ + u8 rx_prefix[EFX_MAX_RX_PREFIX_SIZE]; + struct efx_rx_queue *rx_queue; + struct bpf_prog *xdp_prog; + struct xdp_frame *xdpf; + struct xdp_buff xdp; + u32 xdp_act; + s16 offset; + int err; + + xdp_prog = rcu_dereference_bh(efx->xdp_prog); + if (!xdp_prog) + return true; + + rx_queue = efx_channel_get_rx_queue(channel); + + if (unlikely(channel->rx_pkt_n_frags > 1)) { + /* We can't do XDP on fragmented packets - drop. */ + efx_free_rx_buffers(rx_queue, rx_buf, + channel->rx_pkt_n_frags); + if (net_ratelimit()) + netif_err(efx, rx_err, efx->net_dev, + "XDP is not possible with multiple receive fragments (%d)\n", + channel->rx_pkt_n_frags); + channel->n_rx_xdp_bad_drops++; + return false; + } + + dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, + rx_buf->len, DMA_FROM_DEVICE); + + /* Save the rx prefix. */ + EFX_WARN_ON_PARANOID(efx->rx_prefix_size > EFX_MAX_RX_PREFIX_SIZE); + memcpy(rx_prefix, *ehp - efx->rx_prefix_size, + efx->rx_prefix_size); + + xdp_init_buff(&xdp, efx->rx_page_buf_step, &rx_queue->xdp_rxq_info); + /* No support yet for XDP metadata */ + xdp_prepare_buff(&xdp, *ehp - EFX_XDP_HEADROOM, EFX_XDP_HEADROOM, + rx_buf->len, false); + + xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp); + + offset = (u8 *)xdp.data - *ehp; + + switch (xdp_act) { + case XDP_PASS: + /* Fix up rx prefix. */ + if (offset) { + *ehp += offset; + rx_buf->page_offset += offset; + rx_buf->len -= offset; + memcpy(*ehp - efx->rx_prefix_size, rx_prefix, + efx->rx_prefix_size); + } + break; + + case XDP_TX: + /* Buffer ownership passes to tx on success. */ + xdpf = xdp_convert_buff_to_frame(&xdp); + err = efx_xdp_tx_buffers(efx, 1, &xdpf, true); + if (unlikely(err != 1)) { + efx_free_rx_buffers(rx_queue, rx_buf, 1); + if (net_ratelimit()) + netif_err(efx, rx_err, efx->net_dev, + "XDP TX failed (%d)\n", err); + channel->n_rx_xdp_bad_drops++; + trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act); + } else { + channel->n_rx_xdp_tx++; + } + break; + + case XDP_REDIRECT: + err = xdp_do_redirect(efx->net_dev, &xdp, xdp_prog); + if (unlikely(err)) { + efx_free_rx_buffers(rx_queue, rx_buf, 1); + if (net_ratelimit()) + netif_err(efx, rx_err, efx->net_dev, + "XDP redirect failed (%d)\n", err); + channel->n_rx_xdp_bad_drops++; + trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act); + } else { + channel->n_rx_xdp_redirect++; + } + break; + + default: + bpf_warn_invalid_xdp_action(efx->net_dev, xdp_prog, xdp_act); + efx_free_rx_buffers(rx_queue, rx_buf, 1); + channel->n_rx_xdp_bad_drops++; + trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act); + break; + + case XDP_ABORTED: + trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act); + fallthrough; + case XDP_DROP: + efx_free_rx_buffers(rx_queue, rx_buf, 1); + channel->n_rx_xdp_drops++; + break; + } + + return xdp_act == XDP_PASS; +} + +/* 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)) { + struct efx_rx_queue *rx_queue; + + efx_loopback_rx_packet(efx, eh, rx_buf->len); + rx_queue = efx_channel_get_rx_queue(channel); + efx_free_rx_buffers(rx_queue, rx_buf, + channel->rx_pkt_n_frags); + goto out; + } + + if (!efx_do_xdp(efx, channel, rx_buf, &eh)) + 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, 0); + else + efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags); +out: + channel->rx_pkt_n_frags = 0; +} -- cgit v1.2.3