1 files changed, 574 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
new file mode 100644
index 000000000..1703c640a
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
@@ -0,0 +1,574 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2018 Intel Corporation. */
+
+#include <linux/bpf_trace.h>
+#include <net/xdp_sock_drv.h>
+#include <net/xdp.h>
+
+#include "ixgbe.h"
+#include "ixgbe_txrx_common.h"
+
+struct xsk_buff_pool *ixgbe_xsk_pool(struct ixgbe_adapter *adapter,
+				     struct ixgbe_ring *ring)
+{
+	bool xdp_on = READ_ONCE(adapter->xdp_prog);
+	int qid = ring->ring_idx;
+
+	if (!xdp_on || !test_bit(qid, adapter->af_xdp_zc_qps))
+		return NULL;
+
+	return xsk_get_pool_from_qid(adapter->netdev, qid);
+}
+
+static int ixgbe_xsk_pool_enable(struct ixgbe_adapter *adapter,
+				 struct xsk_buff_pool *pool,
+				 u16 qid)
+{
+	struct net_device *netdev = adapter->netdev;
+	bool if_running;
+	int err;
+
+	if (qid >= adapter->num_rx_queues)
+		return -EINVAL;
+
+	if (qid >= netdev->real_num_rx_queues ||
+	    qid >= netdev->real_num_tx_queues)
+		return -EINVAL;
+
+	err = xsk_pool_dma_map(pool, &adapter->pdev->dev, IXGBE_RX_DMA_ATTR);
+	if (err)
+		return err;
+
+	if_running = netif_running(adapter->netdev) &&
+		     ixgbe_enabled_xdp_adapter(adapter);
+
+	if (if_running)
+		ixgbe_txrx_ring_disable(adapter, qid);
+
+	set_bit(qid, adapter->af_xdp_zc_qps);
+
+	if (if_running) {
+		ixgbe_txrx_ring_enable(adapter, qid);
+
+		/* Kick start the NAPI context so that receiving will start */
+		err = ixgbe_xsk_wakeup(adapter->netdev, qid, XDP_WAKEUP_RX);
+		if (err) {
+			clear_bit(qid, adapter->af_xdp_zc_qps);
+			xsk_pool_dma_unmap(pool, IXGBE_RX_DMA_ATTR);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static int ixgbe_xsk_pool_disable(struct ixgbe_adapter *adapter, u16 qid)
+{
+	struct xsk_buff_pool *pool;
+	bool if_running;
+
+	pool = xsk_get_pool_from_qid(adapter->netdev, qid);
+	if (!pool)
+		return -EINVAL;
+
+	if_running = netif_running(adapter->netdev) &&
+		     ixgbe_enabled_xdp_adapter(adapter);
+
+	if (if_running)
+		ixgbe_txrx_ring_disable(adapter, qid);
+
+	clear_bit(qid, adapter->af_xdp_zc_qps);
+	xsk_pool_dma_unmap(pool, IXGBE_RX_DMA_ATTR);
+
+	if (if_running)
+		ixgbe_txrx_ring_enable(adapter, qid);
+
+	return 0;
+}
+
+int ixgbe_xsk_pool_setup(struct ixgbe_adapter *adapter,
+			 struct xsk_buff_pool *pool,
+			 u16 qid)
+{
+	return pool ? ixgbe_xsk_pool_enable(adapter, pool, qid) :
+		ixgbe_xsk_pool_disable(adapter, qid);
+}
+
+static int ixgbe_run_xdp_zc(struct ixgbe_adapter *adapter,
+			    struct ixgbe_ring *rx_ring,
+			    struct xdp_buff *xdp)
+{
+	int err, result = IXGBE_XDP_PASS;
+	struct bpf_prog *xdp_prog;
+	struct ixgbe_ring *ring;
+	struct xdp_frame *xdpf;
+	u32 act;
+
+	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
+	act = bpf_prog_run_xdp(xdp_prog, xdp);
+
+	if (likely(act == XDP_REDIRECT)) {
+		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
+		if (!err)
+			return IXGBE_XDP_REDIR;
+		if (xsk_uses_need_wakeup(rx_ring->xsk_pool) && err == -ENOBUFS)
+			result = IXGBE_XDP_EXIT;
+		else
+			result = IXGBE_XDP_CONSUMED;
+		goto out_failure;
+	}
+
+	switch (act) {
+	case XDP_PASS:
+		break;
+	case XDP_TX:
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf))
+			goto out_failure;
+		ring = ixgbe_determine_xdp_ring(adapter);
+		if (static_branch_unlikely(&ixgbe_xdp_locking_key))
+			spin_lock(&ring->tx_lock);
+		result = ixgbe_xmit_xdp_ring(ring, xdpf);
+		if (static_branch_unlikely(&ixgbe_xdp_locking_key))
+			spin_unlock(&ring->tx_lock);
+		if (result == IXGBE_XDP_CONSUMED)
+			goto out_failure;
+		break;
+	case XDP_DROP:
+		result = IXGBE_XDP_CONSUMED;
+		break;
+	default:
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
+		fallthrough;
+	case XDP_ABORTED:
+		result = IXGBE_XDP_CONSUMED;
+out_failure:
+		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
+	}
+	return result;
+}
+
+bool ixgbe_alloc_rx_buffers_zc(struct ixgbe_ring *rx_ring, u16 count)
+{
+	union ixgbe_adv_rx_desc *rx_desc;
+	struct ixgbe_rx_buffer *bi;
+	u16 i = rx_ring->next_to_use;
+	dma_addr_t dma;
+	bool ok = true;
+
+	/* nothing to do */
+	if (!count)
+		return true;
+
+	rx_desc = IXGBE_RX_DESC(rx_ring, i);
+	bi = &rx_ring->rx_buffer_info[i];
+	i -= rx_ring->count;
+
+	do {
+		bi->xdp = xsk_buff_alloc(rx_ring->xsk_pool);
+		if (!bi->xdp) {
+			ok = false;
+			break;
+		}
+
+		dma = xsk_buff_xdp_get_dma(bi->xdp);
+
+		/* Refresh the desc even if buffer_addrs didn't change
+		 * because each write-back erases this info.
+		 */
+		rx_desc->read.pkt_addr = cpu_to_le64(dma);
+
+		rx_desc++;
+		bi++;
+		i++;
+		if (unlikely(!i)) {
+			rx_desc = IXGBE_RX_DESC(rx_ring, 0);
+			bi = rx_ring->rx_buffer_info;
+			i -= rx_ring->count;
+		}
+
+		/* clear the length for the next_to_use descriptor */
+		rx_desc->wb.upper.length = 0;
+
+		count--;
+	} while (count);
+
+	i += rx_ring->count;
+
+	if (rx_ring->next_to_use != i) {
+		rx_ring->next_to_use = i;
+
+		/* Force memory writes to complete before letting h/w
+		 * know there are new descriptors to fetch.  (Only
+		 * applicable for weak-ordered memory model archs,
+		 * such as IA-64).
+		 */
+		wmb();
+		writel(i, rx_ring->tail);
+	}
+
+	return ok;
+}
+
+static struct sk_buff *ixgbe_construct_skb_zc(struct ixgbe_ring *rx_ring,
+					      const struct xdp_buff *xdp)
+{
+	unsigned int totalsize = xdp->data_end - xdp->data_meta;
+	unsigned int metasize = xdp->data - xdp->data_meta;
+	struct sk_buff *skb;
+
+	net_prefetch(xdp->data_meta);
+
+	/* allocate a skb to store the frags */
+	skb = __napi_alloc_skb(&rx_ring->q_vector->napi, totalsize,
+			       GFP_ATOMIC | __GFP_NOWARN);
+	if (unlikely(!skb))
+		return NULL;
+
+	memcpy(__skb_put(skb, totalsize), xdp->data_meta,
+	       ALIGN(totalsize, sizeof(long)));
+
+	if (metasize) {
+		skb_metadata_set(skb, metasize);
+		__skb_pull(skb, metasize);
+	}
+
+	return skb;
+}
+
+static void ixgbe_inc_ntc(struct ixgbe_ring *rx_ring)
+{
+	u32 ntc = rx_ring->next_to_clean + 1;
+
+	ntc = (ntc < rx_ring->count) ? ntc : 0;
+	rx_ring->next_to_clean = ntc;
+	prefetch(IXGBE_RX_DESC(rx_ring, ntc));
+}
+
+int ixgbe_clean_rx_irq_zc(struct ixgbe_q_vector *q_vector,
+			  struct ixgbe_ring *rx_ring,
+			  const int budget)
+{
+	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
+	struct ixgbe_adapter *adapter = q_vector->adapter;
+	u16 cleaned_count = ixgbe_desc_unused(rx_ring);
+	unsigned int xdp_res, xdp_xmit = 0;
+	bool failure = false;
+	struct sk_buff *skb;
+
+	while (likely(total_rx_packets < budget)) {
+		union ixgbe_adv_rx_desc *rx_desc;
+		struct ixgbe_rx_buffer *bi;
+		unsigned int size;
+
+		/* return some buffers to hardware, one at a time is too slow */
+		if (cleaned_count >= IXGBE_RX_BUFFER_WRITE) {
+			failure = failure ||
+				  !ixgbe_alloc_rx_buffers_zc(rx_ring,
+							     cleaned_count);
+			cleaned_count = 0;
+		}
+
+		rx_desc = IXGBE_RX_DESC(rx_ring, rx_ring->next_to_clean);
+		size = le16_to_cpu(rx_desc->wb.upper.length);
+		if (!size)
+			break;
+
+		/* This memory barrier is needed to keep us from reading
+		 * any other fields out of the rx_desc until we know the
+		 * descriptor has been written back
+		 */
+		dma_rmb();
+
+		bi = &rx_ring->rx_buffer_info[rx_ring->next_to_clean];
+
+		if (unlikely(!ixgbe_test_staterr(rx_desc,
+						 IXGBE_RXD_STAT_EOP))) {
+			struct ixgbe_rx_buffer *next_bi;
+
+			xsk_buff_free(bi->xdp);
+			bi->xdp = NULL;
+			ixgbe_inc_ntc(rx_ring);
+			next_bi =
+			       &rx_ring->rx_buffer_info[rx_ring->next_to_clean];
+			next_bi->discard = true;
+			continue;
+		}
+
+		if (unlikely(bi->discard)) {
+			xsk_buff_free(bi->xdp);
+			bi->xdp = NULL;
+			bi->discard = false;
+			ixgbe_inc_ntc(rx_ring);
+			continue;
+		}
+
+		bi->xdp->data_end = bi->xdp->data + size;
+		xsk_buff_dma_sync_for_cpu(bi->xdp, rx_ring->xsk_pool);
+		xdp_res = ixgbe_run_xdp_zc(adapter, rx_ring, bi->xdp);
+
+		if (likely(xdp_res & (IXGBE_XDP_TX | IXGBE_XDP_REDIR))) {
+			xdp_xmit |= xdp_res;
+		} else if (xdp_res == IXGBE_XDP_EXIT) {
+			failure = true;
+			break;
+		} else if (xdp_res == IXGBE_XDP_CONSUMED) {
+			xsk_buff_free(bi->xdp);
+		} else if (xdp_res == IXGBE_XDP_PASS) {
+			goto construct_skb;
+		}
+
+		bi->xdp = NULL;
+		total_rx_packets++;
+		total_rx_bytes += size;
+
+		cleaned_count++;
+		ixgbe_inc_ntc(rx_ring);
+		continue;
+
+construct_skb:
+		/* XDP_PASS path */
+		skb = ixgbe_construct_skb_zc(rx_ring, bi->xdp);
+		if (!skb) {
+			rx_ring->rx_stats.alloc_rx_buff_failed++;
+			break;
+		}
+
+		xsk_buff_free(bi->xdp);
+		bi->xdp = NULL;
+
+		cleaned_count++;
+		ixgbe_inc_ntc(rx_ring);
+
+		if (eth_skb_pad(skb))
+			continue;
+
+		total_rx_bytes += skb->len;
+		total_rx_packets++;
+
+		ixgbe_process_skb_fields(rx_ring, rx_desc, skb);
+		ixgbe_rx_skb(q_vector, skb);
+	}
+
+	if (xdp_xmit & IXGBE_XDP_REDIR)
+		xdp_do_flush_map();
+
+	if (xdp_xmit & IXGBE_XDP_TX) {
+		struct ixgbe_ring *ring = ixgbe_determine_xdp_ring(adapter);
+
+		ixgbe_xdp_ring_update_tail_locked(ring);
+	}
+
+	u64_stats_update_begin(&rx_ring->syncp);
+	rx_ring->stats.packets += total_rx_packets;
+	rx_ring->stats.bytes += total_rx_bytes;
+	u64_stats_update_end(&rx_ring->syncp);
+	q_vector->rx.total_packets += total_rx_packets;
+	q_vector->rx.total_bytes += total_rx_bytes;
+
+	if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) {
+		if (failure || rx_ring->next_to_clean == rx_ring->next_to_use)
+			xsk_set_rx_need_wakeup(rx_ring->xsk_pool);
+		else
+			xsk_clear_rx_need_wakeup(rx_ring->xsk_pool);
+
+		return (int)total_rx_packets;
+	}
+	return failure ? budget : (int)total_rx_packets;
+}
+
+void ixgbe_xsk_clean_rx_ring(struct ixgbe_ring *rx_ring)
+{
+	struct ixgbe_rx_buffer *bi;
+	u16 i;
+
+	for (i = 0; i < rx_ring->count; i++) {
+		bi = &rx_ring->rx_buffer_info[i];
+
+		if (!bi->xdp)
+			continue;
+
+		xsk_buff_free(bi->xdp);
+		bi->xdp = NULL;
+	}
+}
+
+static bool ixgbe_xmit_zc(struct ixgbe_ring *xdp_ring, unsigned int budget)
+{
+	struct xsk_buff_pool *pool = xdp_ring->xsk_pool;
+	union ixgbe_adv_tx_desc *tx_desc = NULL;
+	struct ixgbe_tx_buffer *tx_bi;
+	bool work_done = true;
+	struct xdp_desc desc;
+	dma_addr_t dma;
+	u32 cmd_type;
+
+	while (budget-- > 0) {
+		if (unlikely(!ixgbe_desc_unused(xdp_ring))) {
+			work_done = false;
+			break;
+		}
+
+		if (!netif_carrier_ok(xdp_ring->netdev))
+			break;
+
+		if (!xsk_tx_peek_desc(pool, &desc))
+			break;
+
+		dma = xsk_buff_raw_get_dma(pool, desc.addr);
+		xsk_buff_raw_dma_sync_for_device(pool, dma, desc.len);
+
+		tx_bi = &xdp_ring->tx_buffer_info[xdp_ring->next_to_use];
+		tx_bi->bytecount = desc.len;
+		tx_bi->xdpf = NULL;
+		tx_bi->gso_segs = 1;
+
+		tx_desc = IXGBE_TX_DESC(xdp_ring, xdp_ring->next_to_use);
+		tx_desc->read.buffer_addr = cpu_to_le64(dma);
+
+		/* put descriptor type bits */
+		cmd_type = IXGBE_ADVTXD_DTYP_DATA |
+			   IXGBE_ADVTXD_DCMD_DEXT |
+			   IXGBE_ADVTXD_DCMD_IFCS;
+		cmd_type |= desc.len | IXGBE_TXD_CMD;
+		tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type);
+		tx_desc->read.olinfo_status =
+			cpu_to_le32(desc.len << IXGBE_ADVTXD_PAYLEN_SHIFT);
+
+		xdp_ring->next_to_use++;
+		if (xdp_ring->next_to_use == xdp_ring->count)
+			xdp_ring->next_to_use = 0;
+	}
+
+	if (tx_desc) {
+		ixgbe_xdp_ring_update_tail(xdp_ring);
+		xsk_tx_release(pool);
+	}
+
+	return !!budget && work_done;
+}
+
+static void ixgbe_clean_xdp_tx_buffer(struct ixgbe_ring *tx_ring,
+				      struct ixgbe_tx_buffer *tx_bi)
+{
+	xdp_return_frame(tx_bi->xdpf);
+	dma_unmap_single(tx_ring->dev,
+			 dma_unmap_addr(tx_bi, dma),
+			 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
+	dma_unmap_len_set(tx_bi, len, 0);
+}
+
+bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector,
+			    struct ixgbe_ring *tx_ring, int napi_budget)
+{
+	u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
+	unsigned int total_packets = 0, total_bytes = 0;
+	struct xsk_buff_pool *pool = tx_ring->xsk_pool;
+	union ixgbe_adv_tx_desc *tx_desc;
+	struct ixgbe_tx_buffer *tx_bi;
+	u32 xsk_frames = 0;
+
+	tx_bi = &tx_ring->tx_buffer_info[ntc];
+	tx_desc = IXGBE_TX_DESC(tx_ring, ntc);
+
+	while (ntc != ntu) {
+		if (!(tx_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)))
+			break;
+
+		total_bytes += tx_bi->bytecount;
+		total_packets += tx_bi->gso_segs;
+
+		if (tx_bi->xdpf)
+			ixgbe_clean_xdp_tx_buffer(tx_ring, tx_bi);
+		else
+			xsk_frames++;
+
+		tx_bi->xdpf = NULL;
+
+		tx_bi++;
+		tx_desc++;
+		ntc++;
+		if (unlikely(ntc == tx_ring->count)) {
+			ntc = 0;
+			tx_bi = tx_ring->tx_buffer_info;
+			tx_desc = IXGBE_TX_DESC(tx_ring, 0);
+		}
+
+		/* issue prefetch for next Tx descriptor */
+		prefetch(tx_desc);
+	}
+
+	tx_ring->next_to_clean = ntc;
+
+	u64_stats_update_begin(&tx_ring->syncp);
+	tx_ring->stats.bytes += total_bytes;
+	tx_ring->stats.packets += total_packets;
+	u64_stats_update_end(&tx_ring->syncp);
+	q_vector->tx.total_bytes += total_bytes;
+	q_vector->tx.total_packets += total_packets;
+
+	if (xsk_frames)
+		xsk_tx_completed(pool, xsk_frames);
+
+	if (xsk_uses_need_wakeup(pool))
+		xsk_set_tx_need_wakeup(pool);
+
+	return ixgbe_xmit_zc(tx_ring, q_vector->tx.work_limit);
+}
+
+int ixgbe_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags)
+{
+	struct ixgbe_adapter *adapter = netdev_priv(dev);
+	struct ixgbe_ring *ring;
+
+	if (test_bit(__IXGBE_DOWN, &adapter->state))
+		return -ENETDOWN;
+
+	if (!READ_ONCE(adapter->xdp_prog))
+		return -EINVAL;
+
+	if (qid >= adapter->num_xdp_queues)
+		return -EINVAL;
+
+	ring = adapter->xdp_ring[qid];
+
+	if (test_bit(__IXGBE_TX_DISABLED, &ring->state))
+		return -ENETDOWN;
+
+	if (!ring->xsk_pool)
+		return -EINVAL;
+
+	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi)) {
+		u64 eics = BIT_ULL(ring->q_vector->v_idx);
+
+		ixgbe_irq_rearm_queues(adapter, eics);
+	}
+
+	return 0;
+}
+
+void ixgbe_xsk_clean_tx_ring(struct ixgbe_ring *tx_ring)
+{
+	u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
+	struct xsk_buff_pool *pool = tx_ring->xsk_pool;
+	struct ixgbe_tx_buffer *tx_bi;
+	u32 xsk_frames = 0;
+
+	while (ntc != ntu) {
+		tx_bi = &tx_ring->tx_buffer_info[ntc];
+
+		if (tx_bi->xdpf)
+			ixgbe_clean_xdp_tx_buffer(tx_ring, tx_bi);
+		else
+			xsk_frames++;
+
+		tx_bi->xdpf = NULL;
+
+		ntc++;
+		if (ntc == tx_ring->count)
+			ntc = 0;
+	}
+
+	if (xsk_frames)
+		xsk_tx_completed(pool, xsk_frames);
+}