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-rw-r--r--drivers/net/ethernet/sfc/falcon/rx.c979
1 files changed, 979 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/falcon/rx.c b/drivers/net/ethernet/sfc/falcon/rx.c
new file mode 100644
index 000000000..6bbdb5d2e
--- /dev/null
+++ b/drivers/net/ethernet/sfc/falcon/rx.c
@@ -0,0 +1,979 @@
+// 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 <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 EF4_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 EF4_RECYCLE_RING_SIZE_IOMMU 4096
+#define EF4_RECYCLE_RING_SIZE_NOIOMMU (2 * EF4_RX_PREFERRED_BATCH)
+
+/* Size of buffer allocated for skb header area. */
+#define EF4_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 EF4_RX_MAX_FRAGS DIV_ROUND_UP(EF4_MAX_FRAME_LEN(EF4_MAX_MTU), \
+ EF4_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 EF4_RXD_HEAD_ROOM (1 + EF4_RX_MAX_FRAGS)
+
+static inline u8 *ef4_rx_buf_va(struct ef4_rx_buffer *buf)
+{
+ return page_address(buf->page) + buf->page_offset;
+}
+
+static inline u32 ef4_rx_buf_hash(struct ef4_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 ef4_rx_buffer *
+ef4_rx_buf_next(struct ef4_rx_queue *rx_queue, struct ef4_rx_buffer *rx_buf)
+{
+ if (unlikely(rx_buf == ef4_rx_buffer(rx_queue, rx_queue->ptr_mask)))
+ return ef4_rx_buffer(rx_queue, 0);
+ else
+ return rx_buf + 1;
+}
+
+static inline void ef4_sync_rx_buffer(struct ef4_nic *efx,
+ struct ef4_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 ef4_rx_config_page_split(struct ef4_nic *efx)
+{
+ efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align,
+ EF4_RX_BUF_ALIGNMENT);
+ efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
+ ((PAGE_SIZE - sizeof(struct ef4_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(EF4_RX_PREFERRED_BATCH,
+ efx->rx_bufs_per_page);
+}
+
+/* Check the RX page recycle ring for a page that can be reused. */
+static struct page *ef4_reuse_page(struct ef4_rx_queue *rx_queue)
+{
+ struct ef4_nic *efx = rx_queue->efx;
+ struct page *page;
+ struct ef4_rx_page_state *state;
+ unsigned index;
+
+ if (unlikely(!rx_queue->page_ring))
+ return NULL;
+ 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;
+}
+
+/**
+ * ef4_init_rx_buffers - create EF4_RX_BATCH page-based RX buffers
+ *
+ * @rx_queue: Efx RX queue
+ * @atomic: control memory allocation flags
+ *
+ * This allocates a batch of pages, maps them for DMA, and populates
+ * struct ef4_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 ef4_init_rx_buffers(struct ef4_rx_queue *rx_queue, bool atomic)
+{
+ struct ef4_nic *efx = rx_queue->efx;
+ struct ef4_rx_buffer *rx_buf;
+ struct page *page;
+ unsigned int page_offset;
+ struct ef4_rx_page_state *state;
+ dma_addr_t dma_addr;
+ unsigned index, count;
+
+ count = 0;
+ do {
+ page = ef4_reuse_page(rx_queue);
+ if (page == NULL) {
+ page = alloc_pages(__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 ef4_rx_page_state);
+ page_offset = sizeof(struct ef4_rx_page_state);
+
+ do {
+ index = rx_queue->added_count & rx_queue->ptr_mask;
+ rx_buf = ef4_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 = EF4_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 ef4_unmap_rx_buffer(struct ef4_nic *efx,
+ struct ef4_rx_buffer *rx_buf)
+{
+ struct page *page = rx_buf->page;
+
+ if (page) {
+ struct ef4_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 ef4_free_rx_buffers(struct ef4_rx_queue *rx_queue,
+ struct ef4_rx_buffer *rx_buf,
+ unsigned int num_bufs)
+{
+ do {
+ if (rx_buf->page) {
+ put_page(rx_buf->page);
+ rx_buf->page = NULL;
+ }
+ rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
+ } while (--num_bufs);
+}
+
+/* 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 ef4_recycle_rx_page(struct ef4_channel *channel,
+ struct ef4_rx_buffer *rx_buf)
+{
+ struct page *page = rx_buf->page;
+ struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
+ struct ef4_nic *efx = rx_queue->efx;
+ unsigned index;
+
+ /* Only recycle the page after processing the final buffer. */
+ if (!(rx_buf->flags & EF4_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;
+ ef4_unmap_rx_buffer(efx, rx_buf);
+ put_page(rx_buf->page);
+}
+
+static void ef4_fini_rx_buffer(struct ef4_rx_queue *rx_queue,
+ struct ef4_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 & EF4_RX_BUF_LAST_IN_PAGE) {
+ ef4_unmap_rx_buffer(rx_queue->efx, rx_buf);
+ ef4_free_rx_buffers(rx_queue, rx_buf, 1);
+ }
+ rx_buf->page = NULL;
+}
+
+/* Recycle the pages that are used by buffers that have just been received. */
+static void ef4_recycle_rx_pages(struct ef4_channel *channel,
+ struct ef4_rx_buffer *rx_buf,
+ unsigned int n_frags)
+{
+ struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
+
+ if (unlikely(!rx_queue->page_ring))
+ return;
+
+ do {
+ ef4_recycle_rx_page(channel, rx_buf);
+ rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
+ } while (--n_frags);
+}
+
+static void ef4_discard_rx_packet(struct ef4_channel *channel,
+ struct ef4_rx_buffer *rx_buf,
+ unsigned int n_frags)
+{
+ struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
+
+ ef4_recycle_rx_pages(channel, rx_buf, n_frags);
+
+ ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
+}
+
+/**
+ * ef4_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.
+ * @atomic: control memory allocation flags
+ *
+ * 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 ef4_fast_push_rx_descriptors(struct ef4_rx_queue *rx_queue, bool atomic)
+{
+ struct ef4_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);
+ EF4_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;
+ EF4_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",
+ ef4_rx_queue_index(rx_queue), fill_level,
+ rx_queue->max_fill);
+
+
+ do {
+ rc = ef4_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)
+ ef4_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", ef4_rx_queue_index(rx_queue),
+ rx_queue->added_count - rx_queue->removed_count);
+
+ out:
+ if (rx_queue->notified_count != rx_queue->added_count)
+ ef4_nic_notify_rx_desc(rx_queue);
+}
+
+void ef4_rx_slow_fill(struct timer_list *t)
+{
+ struct ef4_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);
+
+ /* Post an event to cause NAPI to run and refill the queue */
+ ef4_nic_generate_fill_event(rx_queue);
+ ++rx_queue->slow_fill_count;
+}
+
+static void ef4_rx_packet__check_len(struct ef4_rx_queue *rx_queue,
+ struct ef4_rx_buffer *rx_buf,
+ int len)
+{
+ struct ef4_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 |= EF4_RX_PKT_DISCARD;
+
+ if ((len > rx_buf->len) && EF4_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",
+ ef4_rx_queue_index(rx_queue), len, max_len,
+ efx->type->rx_buffer_padding);
+ ef4_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",
+ ef4_rx_queue_index(rx_queue), len, max_len);
+ }
+
+ ef4_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
+ef4_rx_packet_gro(struct ef4_channel *channel, struct ef4_rx_buffer *rx_buf,
+ unsigned int n_frags, u8 *eh)
+{
+ struct napi_struct *napi = &channel->napi_str;
+ struct ef4_nic *efx = channel->efx;
+ struct sk_buff *skb;
+
+ skb = napi_get_frags(napi);
+ if (unlikely(!skb)) {
+ struct ef4_rx_queue *rx_queue;
+
+ rx_queue = ef4_channel_get_rx_queue(channel);
+ ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
+ return;
+ }
+
+ if (efx->net_dev->features & NETIF_F_RXHASH)
+ skb_set_hash(skb, ef4_rx_buf_hash(efx, eh),
+ PKT_HASH_TYPE_L3);
+ skb->ip_summed = ((rx_buf->flags & EF4_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 = ef4_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);
+
+ napi_gro_frags(napi);
+}
+
+/* Allocate and construct an SKB around page fragments */
+static struct sk_buff *ef4_rx_mk_skb(struct ef4_channel *channel,
+ struct ef4_rx_buffer *rx_buf,
+ unsigned int n_frags,
+ u8 *eh, int hdr_len)
+{
+ struct ef4_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;
+ }
+
+ EF4_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 = ef4_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);
+
+ skb_mark_napi_id(skb, &channel->napi_str);
+
+ return skb;
+}
+
+void ef4_rx_packet(struct ef4_rx_queue *rx_queue, unsigned int index,
+ unsigned int n_frags, unsigned int len, u16 flags)
+{
+ struct ef4_nic *efx = rx_queue->efx;
+ struct ef4_channel *channel = ef4_rx_queue_channel(rx_queue);
+ struct ef4_rx_buffer *rx_buf;
+
+ rx_queue->rx_packets++;
+
+ rx_buf = ef4_rx_buffer(rx_queue, index);
+ rx_buf->flags |= flags;
+
+ /* Validate the number of fragments and completed length */
+ if (n_frags == 1) {
+ if (!(flags & EF4_RX_PKT_PREFIX_LEN))
+ ef4_rx_packet__check_len(rx_queue, rx_buf, len);
+ } else if (unlikely(n_frags > EF4_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 & EF4_RX_PKT_DISCARD));
+ rx_buf->flags |= EF4_RX_PKT_DISCARD;
+ }
+
+ netif_vdbg(efx, rx_status, efx->net_dev,
+ "RX queue %d received ids %x-%x len %d %s%s\n",
+ ef4_rx_queue_index(rx_queue), index,
+ (index + n_frags - 1) & rx_queue->ptr_mask, len,
+ (rx_buf->flags & EF4_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
+ (rx_buf->flags & EF4_RX_PKT_DISCARD) ? " [DISCARD]" : "");
+
+ /* Discard packet, if instructed to do so. Process the
+ * previous receive first.
+ */
+ if (unlikely(rx_buf->flags & EF4_RX_PKT_DISCARD)) {
+ ef4_rx_flush_packet(channel);
+ ef4_discard_rx_packet(channel, rx_buf, n_frags);
+ return;
+ }
+
+ if (n_frags == 1 && !(flags & EF4_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.
+ */
+ ef4_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(ef4_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 = ef4_rx_buf_next(rx_queue, rx_buf);
+ if (--tail_frags == 0)
+ break;
+ ef4_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
+ }
+ rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
+ ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
+ }
+
+ /* All fragments have been DMA-synced, so recycle pages. */
+ rx_buf = ef4_rx_buffer(rx_queue, index);
+ ef4_recycle_rx_pages(channel, rx_buf, n_frags);
+
+ /* Pipeline receives so that we give time for packet headers to be
+ * prefetched into cache.
+ */
+ ef4_rx_flush_packet(channel);
+ channel->rx_pkt_n_frags = n_frags;
+ channel->rx_pkt_index = index;
+}
+
+static void ef4_rx_deliver(struct ef4_channel *channel, u8 *eh,
+ struct ef4_rx_buffer *rx_buf,
+ unsigned int n_frags)
+{
+ struct sk_buff *skb;
+ u16 hdr_len = min_t(u16, rx_buf->len, EF4_SKB_HEADERS);
+
+ skb = ef4_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
+ if (unlikely(skb == NULL)) {
+ struct ef4_rx_queue *rx_queue;
+
+ rx_queue = ef4_channel_get_rx_queue(channel);
+ ef4_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 & EF4_RX_PKT_CSUMMED))
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ 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 __ef4_rx_packet(struct ef4_channel *channel)
+{
+ struct ef4_nic *efx = channel->efx;
+ struct ef4_rx_buffer *rx_buf =
+ ef4_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
+ u8 *eh = ef4_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 & EF4_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 ef4_rx_queue *rx_queue;
+
+ ef4_loopback_rx_packet(efx, eh, rx_buf->len);
+ rx_queue = ef4_channel_get_rx_queue(channel);
+ ef4_free_rx_buffers(rx_queue, rx_buf,
+ channel->rx_pkt_n_frags);
+ goto out;
+ }
+
+ if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
+ rx_buf->flags &= ~EF4_RX_PKT_CSUMMED;
+
+ if ((rx_buf->flags & EF4_RX_PKT_TCP) && !channel->type->receive_skb)
+ ef4_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
+ else
+ ef4_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
+out:
+ channel->rx_pkt_n_frags = 0;
+}
+
+int ef4_probe_rx_queue(struct ef4_rx_queue *rx_queue)
+{
+ struct ef4_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), EF4_MIN_DMAQ_SIZE);
+ EF4_BUG_ON_PARANOID(entries > EF4_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",
+ ef4_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 = ef4_nic_probe_rx(rx_queue);
+ if (rc) {
+ kfree(rx_queue->buffer);
+ rx_queue->buffer = NULL;
+ }
+
+ return rc;
+}
+
+static void ef4_init_rx_recycle_ring(struct ef4_nic *efx,
+ struct ef4_rx_queue *rx_queue)
+{
+ unsigned int bufs_in_recycle_ring, page_ring_size;
+ struct iommu_domain __maybe_unused *domain;
+
+ /* Set the RX recycle ring size */
+#ifdef CONFIG_PPC64
+ bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
+#else
+ domain = iommu_get_domain_for_dev(&efx->pci_dev->dev);
+ if (domain && domain->type != IOMMU_DOMAIN_IDENTITY)
+ bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
+ else
+ bufs_in_recycle_ring = EF4_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);
+ if (!rx_queue->page_ring)
+ rx_queue->page_ptr_mask = 0;
+ else
+ rx_queue->page_ptr_mask = page_ring_size - 1;
+}
+
+void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue)
+{
+ struct ef4_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", ef4_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;
+ ef4_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 - EF4_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 */
+ ef4_nic_init_rx(rx_queue);
+}
+
+void ef4_fini_rx_queue(struct ef4_rx_queue *rx_queue)
+{
+ int i;
+ struct ef4_nic *efx = rx_queue->efx;
+ struct ef4_rx_buffer *rx_buf;
+
+ netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
+ "shutting down RX queue %d\n", ef4_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 = ef4_rx_buffer(rx_queue, index);
+ ef4_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 ef4_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 ef4_remove_rx_queue(struct ef4_rx_queue *rx_queue)
+{
+ netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
+ "destroying RX queue %d\n", ef4_rx_queue_index(rx_queue));
+
+ ef4_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 ef4_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
+ u16 rxq_index, u32 flow_id)
+{
+ struct ef4_nic *efx = netdev_priv(net_dev);
+ struct ef4_channel *channel;
+ struct ef4_filter_spec spec;
+ struct flow_keys fk;
+ int rc;
+
+ if (flow_id == RPS_FLOW_ID_INVALID)
+ return -EINVAL;
+
+ if (!skb_flow_dissect_flow_keys(skb, &fk, 0))
+ return -EPROTONOSUPPORT;
+
+ if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6))
+ return -EPROTONOSUPPORT;
+ if (fk.control.flags & FLOW_DIS_IS_FRAGMENT)
+ return -EPROTONOSUPPORT;
+
+ ef4_filter_init_rx(&spec, EF4_FILTER_PRI_HINT,
+ efx->rx_scatter ? EF4_FILTER_FLAG_RX_SCATTER : 0,
+ rxq_index);
+ spec.match_flags =
+ EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_IP_PROTO |
+ EF4_FILTER_MATCH_LOC_HOST | EF4_FILTER_MATCH_LOC_PORT |
+ EF4_FILTER_MATCH_REM_HOST | EF4_FILTER_MATCH_REM_PORT;
+ spec.ether_type = fk.basic.n_proto;
+ spec.ip_proto = fk.basic.ip_proto;
+
+ if (fk.basic.n_proto == htons(ETH_P_IP)) {
+ spec.rem_host[0] = fk.addrs.v4addrs.src;
+ spec.loc_host[0] = fk.addrs.v4addrs.dst;
+ } else {
+ memcpy(spec.rem_host, &fk.addrs.v6addrs.src, sizeof(struct in6_addr));
+ memcpy(spec.loc_host, &fk.addrs.v6addrs.dst, sizeof(struct in6_addr));
+ }
+
+ spec.rem_port = fk.ports.src;
+ spec.loc_port = fk.ports.dst;
+
+ 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 */
+ channel = ef4_get_channel(efx, rxq_index);
+ channel->rps_flow_id[rc] = flow_id;
+ ++channel->rfs_filters_added;
+
+ if (spec.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(spec.rem_port), spec.loc_host,
+ ntohs(spec.loc_port), 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(spec.rem_port), spec.loc_host,
+ ntohs(spec.loc_port), rxq_index, flow_id, rc);
+
+ return rc;
+}
+
+bool __ef4_filter_rfs_expire(struct ef4_nic *efx, unsigned int quota)
+{
+ bool (*expire_one)(struct ef4_nic *efx, u32 flow_id, unsigned int index);
+ unsigned int channel_idx, index, size;
+ u32 flow_id;
+
+ if (!spin_trylock_bh(&efx->filter_lock))
+ return false;
+
+ expire_one = efx->type->filter_rfs_expire_one;
+ channel_idx = efx->rps_expire_channel;
+ index = efx->rps_expire_index;
+ size = efx->type->max_rx_ip_filters;
+ while (quota--) {
+ struct ef4_channel *channel = ef4_get_channel(efx, channel_idx);
+ flow_id = channel->rps_flow_id[index];
+
+ if (flow_id != RPS_FLOW_ID_INVALID &&
+ expire_one(efx, flow_id, index)) {
+ netif_info(efx, rx_status, efx->net_dev,
+ "expired filter %d [queue %u flow %u]\n",
+ index, channel_idx, flow_id);
+ channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;
+ }
+ if (++index == size) {
+ if (++channel_idx == efx->n_channels)
+ channel_idx = 0;
+ index = 0;
+ }
+ }
+ efx->rps_expire_channel = channel_idx;
+ efx->rps_expire_index = index;
+
+ spin_unlock_bh(&efx->filter_lock);
+ return true;
+}
+
+#endif /* CONFIG_RFS_ACCEL */
+
+/**
+ * ef4_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 ef4_filter_is_mc_recipient(const struct ef4_filter_spec *spec)
+{
+ if (!(spec->flags & EF4_FILTER_FLAG_RX) ||
+ spec->dmaq_id == EF4_FILTER_RX_DMAQ_ID_DROP)
+ return false;
+
+ if (spec->match_flags &
+ (EF4_FILTER_MATCH_LOC_MAC | EF4_FILTER_MATCH_LOC_MAC_IG) &&
+ is_multicast_ether_addr(spec->loc_mac))
+ return true;
+
+ if ((spec->match_flags &
+ (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) ==
+ (EF4_FILTER_MATCH_ETHER_TYPE | EF4_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;
+}