1 files changed, 419 insertions, 0 deletions

diff --git a/drivers/net/vmxnet3/vmxnet3_xdp.c b/drivers/net/vmxnet3/vmxnet3_xdp.c
new file mode 100644
index 000000000000..80ddaff759d4
--- /dev/null
+++ b/drivers/net/vmxnet3/vmxnet3_xdp.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux driver for VMware's vmxnet3 ethernet NIC.
+ * Copyright (C) 2008-2023, VMware, Inc. All Rights Reserved.
+ * Maintained by: pv-drivers@vmware.com
+ *
+ */
+
+#include "vmxnet3_int.h"
+#include "vmxnet3_xdp.h"
+
+static void
+vmxnet3_xdp_exchange_program(struct vmxnet3_adapter *adapter,
+			     struct bpf_prog *prog)
+{
+	rcu_assign_pointer(adapter->xdp_bpf_prog, prog);
+}
+
+static inline struct vmxnet3_tx_queue *
+vmxnet3_xdp_get_tq(struct vmxnet3_adapter *adapter)
+{
+	struct vmxnet3_tx_queue *tq;
+	int tq_number;
+	int cpu;
+
+	tq_number = adapter->num_tx_queues;
+	cpu = smp_processor_id();
+	if (likely(cpu < tq_number))
+		tq = &adapter->tx_queue[cpu];
+	else
+		tq = &adapter->tx_queue[reciprocal_scale(cpu, tq_number)];
+
+	return tq;
+}
+
+static int
+vmxnet3_xdp_set(struct net_device *netdev, struct netdev_bpf *bpf,
+		struct netlink_ext_ack *extack)
+{
+	struct vmxnet3_adapter *adapter = netdev_priv(netdev);
+	struct bpf_prog *new_bpf_prog = bpf->prog;
+	struct bpf_prog *old_bpf_prog;
+	bool need_update;
+	bool running;
+	int err;
+
+	if (new_bpf_prog && netdev->mtu > VMXNET3_XDP_MAX_MTU) {
+		NL_SET_ERR_MSG_FMT_MOD(extack, "MTU %u too large for XDP",
+				       netdev->mtu);
+		return -EOPNOTSUPP;
+	}
+
+	if (adapter->netdev->features & NETIF_F_LRO) {
+		NL_SET_ERR_MSG_MOD(extack, "LRO is not supported with XDP");
+		adapter->netdev->features &= ~NETIF_F_LRO;
+	}
+
+	old_bpf_prog = rcu_dereference(adapter->xdp_bpf_prog);
+	if (!new_bpf_prog && !old_bpf_prog)
+		return 0;
+
+	running = netif_running(netdev);
+	need_update = !!old_bpf_prog != !!new_bpf_prog;
+
+	if (running && need_update)
+		vmxnet3_quiesce_dev(adapter);
+
+	vmxnet3_xdp_exchange_program(adapter, new_bpf_prog);
+	if (old_bpf_prog)
+		bpf_prog_put(old_bpf_prog);
+
+	if (!running || !need_update)
+		return 0;
+
+	if (new_bpf_prog)
+		xdp_features_set_redirect_target(netdev, false);
+	else
+		xdp_features_clear_redirect_target(netdev);
+
+	vmxnet3_reset_dev(adapter);
+	vmxnet3_rq_destroy_all(adapter);
+	vmxnet3_adjust_rx_ring_size(adapter);
+	err = vmxnet3_rq_create_all(adapter);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "failed to re-create rx queues for XDP.");
+		return -EOPNOTSUPP;
+	}
+	err = vmxnet3_activate_dev(adapter);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "failed to activate device for XDP.");
+		return -EOPNOTSUPP;
+	}
+	clear_bit(VMXNET3_STATE_BIT_RESETTING, &adapter->state);
+
+	return 0;
+}
+
+/* This is the main xdp call used by kernel to set/unset eBPF program. */
+int
+vmxnet3_xdp(struct net_device *netdev, struct netdev_bpf *bpf)
+{
+	switch (bpf->command) {
+	case XDP_SETUP_PROG:
+		return vmxnet3_xdp_set(netdev, bpf, bpf->extack);
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int
+vmxnet3_xdp_xmit_frame(struct vmxnet3_adapter *adapter,
+		       struct xdp_frame *xdpf,
+		       struct vmxnet3_tx_queue *tq, bool dma_map)
+{
+	struct vmxnet3_tx_buf_info *tbi = NULL;
+	union Vmxnet3_GenericDesc *gdesc;
+	struct vmxnet3_tx_ctx ctx;
+	int tx_num_deferred;
+	struct page *page;
+	u32 buf_size;
+	u32 dw2;
+
+	dw2 = (tq->tx_ring.gen ^ 0x1) << VMXNET3_TXD_GEN_SHIFT;
+	dw2 |= xdpf->len;
+	ctx.sop_txd = tq->tx_ring.base + tq->tx_ring.next2fill;
+	gdesc = ctx.sop_txd;
+
+	buf_size = xdpf->len;
+	tbi = tq->buf_info + tq->tx_ring.next2fill;
+
+	if (vmxnet3_cmd_ring_desc_avail(&tq->tx_ring) == 0) {
+		tq->stats.tx_ring_full++;
+		return -ENOSPC;
+	}
+
+	tbi->map_type = VMXNET3_MAP_XDP;
+	if (dma_map) { /* ndo_xdp_xmit */
+		tbi->dma_addr = dma_map_single(&adapter->pdev->dev,
+					       xdpf->data, buf_size,
+					       DMA_TO_DEVICE);
+		if (dma_mapping_error(&adapter->pdev->dev, tbi->dma_addr))
+			return -EFAULT;
+		tbi->map_type |= VMXNET3_MAP_SINGLE;
+	} else { /* XDP buffer from page pool */
+		page = virt_to_page(xdpf->data);
+		tbi->dma_addr = page_pool_get_dma_addr(page) +
+				VMXNET3_XDP_HEADROOM;
+		dma_sync_single_for_device(&adapter->pdev->dev,
+					   tbi->dma_addr, buf_size,
+					   DMA_TO_DEVICE);
+	}
+	tbi->xdpf = xdpf;
+	tbi->len = buf_size;
+
+	gdesc = tq->tx_ring.base + tq->tx_ring.next2fill;
+	WARN_ON_ONCE(gdesc->txd.gen == tq->tx_ring.gen);
+
+	gdesc->txd.addr = cpu_to_le64(tbi->dma_addr);
+	gdesc->dword[2] = cpu_to_le32(dw2);
+
+	/* Setup the EOP desc */
+	gdesc->dword[3] = cpu_to_le32(VMXNET3_TXD_CQ | VMXNET3_TXD_EOP);
+
+	gdesc->txd.om = 0;
+	gdesc->txd.msscof = 0;
+	gdesc->txd.hlen = 0;
+	gdesc->txd.ti = 0;
+
+	tx_num_deferred = le32_to_cpu(tq->shared->txNumDeferred);
+	le32_add_cpu(&tq->shared->txNumDeferred, 1);
+	tx_num_deferred++;
+
+	vmxnet3_cmd_ring_adv_next2fill(&tq->tx_ring);
+
+	/* set the last buf_info for the pkt */
+	tbi->sop_idx = ctx.sop_txd - tq->tx_ring.base;
+
+	dma_wmb();
+	gdesc->dword[2] = cpu_to_le32(le32_to_cpu(gdesc->dword[2]) ^
+						  VMXNET3_TXD_GEN);
+
+	/* No need to handle the case when tx_num_deferred doesn't reach
+	 * threshold. Backend driver at hypervisor side will poll and reset
+	 * tq->shared->txNumDeferred to 0.
+	 */
+	if (tx_num_deferred >= le32_to_cpu(tq->shared->txThreshold)) {
+		tq->shared->txNumDeferred = 0;
+		VMXNET3_WRITE_BAR0_REG(adapter,
+				       VMXNET3_REG_TXPROD + tq->qid * 8,
+				       tq->tx_ring.next2fill);
+	}
+
+	return 0;
+}
+
+static int
+vmxnet3_xdp_xmit_back(struct vmxnet3_adapter *adapter,
+		      struct xdp_frame *xdpf)
+{
+	struct vmxnet3_tx_queue *tq;
+	struct netdev_queue *nq;
+	int err;
+
+	tq = vmxnet3_xdp_get_tq(adapter);
+	if (tq->stopped)
+		return -ENETDOWN;
+
+	nq = netdev_get_tx_queue(adapter->netdev, tq->qid);
+
+	__netif_tx_lock(nq, smp_processor_id());
+	err = vmxnet3_xdp_xmit_frame(adapter, xdpf, tq, false);
+	__netif_tx_unlock(nq);
+
+	return err;
+}
+
+/* ndo_xdp_xmit */
+int
+vmxnet3_xdp_xmit(struct net_device *dev,
+		 int n, struct xdp_frame **frames, u32 flags)
+{
+	struct vmxnet3_adapter *adapter = netdev_priv(dev);
+	struct vmxnet3_tx_queue *tq;
+	int i;
+
+	if (unlikely(test_bit(VMXNET3_STATE_BIT_QUIESCED, &adapter->state)))
+		return -ENETDOWN;
+	if (unlikely(test_bit(VMXNET3_STATE_BIT_RESETTING, &adapter->state)))
+		return -EINVAL;
+
+	tq = vmxnet3_xdp_get_tq(adapter);
+	if (tq->stopped)
+		return -ENETDOWN;
+
+	for (i = 0; i < n; i++) {
+		if (vmxnet3_xdp_xmit_frame(adapter, frames[i], tq, true)) {
+			tq->stats.xdp_xmit_err++;
+			break;
+		}
+	}
+	tq->stats.xdp_xmit += i;
+
+	return i;
+}
+
+static int
+vmxnet3_run_xdp(struct vmxnet3_rx_queue *rq, struct xdp_buff *xdp,
+		struct bpf_prog *prog)
+{
+	struct xdp_frame *xdpf;
+	struct page *page;
+	int err;
+	u32 act;
+
+	rq->stats.xdp_packets++;
+	act = bpf_prog_run_xdp(prog, xdp);
+	page = virt_to_page(xdp->data_hard_start);
+
+	switch (act) {
+	case XDP_PASS:
+		return act;
+	case XDP_REDIRECT:
+		err = xdp_do_redirect(rq->adapter->netdev, xdp, prog);
+		if (!err) {
+			rq->stats.xdp_redirects++;
+		} else {
+			rq->stats.xdp_drops++;
+			page_pool_recycle_direct(rq->page_pool, page);
+		}
+		return act;
+	case XDP_TX:
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf ||
+			     vmxnet3_xdp_xmit_back(rq->adapter, xdpf))) {
+			rq->stats.xdp_drops++;
+			page_pool_recycle_direct(rq->page_pool, page);
+		} else {
+			rq->stats.xdp_tx++;
+		}
+		return act;
+	default:
+		bpf_warn_invalid_xdp_action(rq->adapter->netdev, prog, act);
+		fallthrough;
+	case XDP_ABORTED:
+		trace_xdp_exception(rq->adapter->netdev, prog, act);
+		rq->stats.xdp_aborted++;
+		break;
+	case XDP_DROP:
+		rq->stats.xdp_drops++;
+		break;
+	}
+
+	page_pool_recycle_direct(rq->page_pool, page);
+
+	return act;
+}
+
+static struct sk_buff *
+vmxnet3_build_skb(struct vmxnet3_rx_queue *rq, struct page *page,
+		  const struct xdp_buff *xdp)
+{
+	struct sk_buff *skb;
+
+	skb = build_skb(page_address(page), PAGE_SIZE);
+	if (unlikely(!skb)) {
+		page_pool_recycle_direct(rq->page_pool, page);
+		rq->stats.rx_buf_alloc_failure++;
+		return NULL;
+	}
+
+	/* bpf prog might change len and data position. */
+	skb_reserve(skb, xdp->data - xdp->data_hard_start);
+	skb_put(skb, xdp->data_end - xdp->data);
+	skb_mark_for_recycle(skb);
+
+	return skb;
+}
+
+/* Handle packets from DataRing. */
+int
+vmxnet3_process_xdp_small(struct vmxnet3_adapter *adapter,
+			  struct vmxnet3_rx_queue *rq,
+			  void *data, int len,
+			  struct sk_buff **skb_xdp_pass)
+{
+	struct bpf_prog *xdp_prog;
+	struct xdp_buff xdp;
+	struct page *page;
+	int act;
+
+	page = page_pool_alloc_pages(rq->page_pool, GFP_ATOMIC);
+	if (unlikely(!page)) {
+		rq->stats.rx_buf_alloc_failure++;
+		return XDP_DROP;
+	}
+
+	xdp_init_buff(&xdp, PAGE_SIZE, &rq->xdp_rxq);
+	xdp_prepare_buff(&xdp, page_address(page), rq->page_pool->p.offset,
+			 len, false);
+	xdp_buff_clear_frags_flag(&xdp);
+
+	/* Must copy the data because it's at dataring. */
+	memcpy(xdp.data, data, len);
+
+	xdp_prog = rcu_dereference(rq->adapter->xdp_bpf_prog);
+	if (!xdp_prog) {
+		act = XDP_PASS;
+		goto out_skb;
+	}
+	act = vmxnet3_run_xdp(rq, &xdp, xdp_prog);
+	if (act != XDP_PASS)
+		return act;
+
+out_skb:
+	*skb_xdp_pass = vmxnet3_build_skb(rq, page, &xdp);
+	if (!*skb_xdp_pass)
+		return XDP_DROP;
+
+	/* No need to refill. */
+	return likely(*skb_xdp_pass) ? act : XDP_DROP;
+}
+
+int
+vmxnet3_process_xdp(struct vmxnet3_adapter *adapter,
+		    struct vmxnet3_rx_queue *rq,
+		    struct Vmxnet3_RxCompDesc *rcd,
+		    struct vmxnet3_rx_buf_info *rbi,
+		    struct Vmxnet3_RxDesc *rxd,
+		    struct sk_buff **skb_xdp_pass)
+{
+	struct bpf_prog *xdp_prog;
+	dma_addr_t new_dma_addr;
+	struct xdp_buff xdp;
+	struct page *page;
+	void *new_data;
+	int act;
+
+	page = rbi->page;
+	dma_sync_single_for_cpu(&adapter->pdev->dev,
+				page_pool_get_dma_addr(page) +
+				rq->page_pool->p.offset, rcd->len,
+				page_pool_get_dma_dir(rq->page_pool));
+
+	xdp_init_buff(&xdp, rbi->len, &rq->xdp_rxq);
+	xdp_prepare_buff(&xdp, page_address(page), rq->page_pool->p.offset,
+			 rcd->len, false);
+	xdp_buff_clear_frags_flag(&xdp);
+
+	xdp_prog = rcu_dereference(rq->adapter->xdp_bpf_prog);
+	if (!xdp_prog) {
+		act = XDP_PASS;
+		goto out_skb;
+	}
+	act = vmxnet3_run_xdp(rq, &xdp, xdp_prog);
+
+	if (act == XDP_PASS) {
+out_skb:
+		*skb_xdp_pass = vmxnet3_build_skb(rq, page, &xdp);
+		if (!*skb_xdp_pass)
+			act = XDP_DROP;
+	}
+
+	new_data = vmxnet3_pp_get_buff(rq->page_pool, &new_dma_addr,
+				       GFP_ATOMIC);
+	if (!new_data) {
+		rq->stats.rx_buf_alloc_failure++;
+		return XDP_DROP;
+	}
+	rbi->page = virt_to_page(new_data);
+	rbi->dma_addr = new_dma_addr;
+	rxd->addr = cpu_to_le64(rbi->dma_addr);
+	rxd->len = rbi->len;
+
+	return act;
+}