3 files changed, 160 insertions, 27 deletions

diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
index a58cc1e7b94a..bb13dee388c3 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
@@ -501,9 +501,8 @@ static int nicvf_init_resources(struct nicvf *nic)
 	return 0;
 }
 
-static inline bool nicvf_xdp_rx(struct nicvf *nic,
-				struct bpf_prog *prog,
-				struct cqe_rx_t *cqe_rx)
+static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
+				struct cqe_rx_t *cqe_rx, struct snd_queue *sq)
 {
 	struct xdp_buff xdp;
 	struct page *page;
@@ -528,9 +527,11 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic,
 
 	switch (action) {
 	case XDP_PASS:
-	case XDP_TX:
-		/* Pass on all packets to network stack */
+		/* Pass on packet to network stack */
 		return false;
+	case XDP_TX:
+		nicvf_xdp_sq_append_pkt(nic, sq, (u64)xdp.data, dma_addr, len);
+		return true;
 	default:
 		bpf_warn_invalid_xdp_action(action);
 	case XDP_ABORTED:
@@ -560,6 +561,7 @@ static void nicvf_snd_pkt_handler(struct net_device *netdev,
 				  unsigned int *tx_pkts, unsigned int *tx_bytes)
 {
 	struct sk_buff *skb = NULL;
+	struct page *page;
 	struct nicvf *nic = netdev_priv(netdev);
 	struct snd_queue *sq;
 	struct sq_hdr_subdesc *hdr;
@@ -575,6 +577,22 @@ static void nicvf_snd_pkt_handler(struct net_device *netdev,
 	if (cqe_tx->send_status)
 		nicvf_check_cqe_tx_errs(nic->pnicvf, cqe_tx);
 
+	/* Is this a XDP designated Tx queue */
+	if (sq->is_xdp) {
+		page = (struct page *)sq->xdp_page[cqe_tx->sqe_ptr];
+		/* Check if it's recycled page or else unmap DMA mapping */
+		if (page && (page_ref_count(page) == 1))
+			nicvf_unmap_sndq_buffers(nic, sq, cqe_tx->sqe_ptr,
+						 hdr->subdesc_cnt);
+
+		/* Release page reference for recycling */
+		if (page)
+			put_page(page);
+		sq->xdp_page[cqe_tx->sqe_ptr] = (u64)NULL;
+		*subdesc_cnt += hdr->subdesc_cnt + 1;
+		return;
+	}
+
 	skb = (struct sk_buff *)sq->skbuff[cqe_tx->sqe_ptr];
 	if (skb) {
 		/* Check for dummy descriptor used for HW TSO offload on 88xx */
@@ -634,7 +652,7 @@ static inline void nicvf_set_rxhash(struct net_device *netdev,
 
 static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 				  struct napi_struct *napi,
-				  struct cqe_rx_t *cqe_rx)
+				  struct cqe_rx_t *cqe_rx, struct snd_queue *sq)
 {
 	struct sk_buff *skb;
 	struct nicvf *nic = netdev_priv(netdev);
@@ -659,7 +677,7 @@ static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 
 	/* For XDP, ignore pkts spanning multiple pages */
 	if (nic->xdp_prog && (cqe_rx->rb_cnt == 1))
-		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx))
+		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx, sq))
 			return;
 
 	skb = nicvf_get_rcv_skb(snic, cqe_rx, nic->xdp_prog ? true : false);
@@ -715,8 +733,8 @@ static int nicvf_cq_intr_handler(struct net_device *netdev, u8 cq_idx,
 	struct cmp_queue *cq = &qs->cq[cq_idx];
 	struct cqe_rx_t *cq_desc;
 	struct netdev_queue *txq;
-	struct snd_queue *sq;
-	unsigned int tx_pkts = 0, tx_bytes = 0;
+	struct snd_queue *sq = &qs->sq[cq_idx];
+	unsigned int tx_pkts = 0, tx_bytes = 0, txq_idx;
 
 	spin_lock_bh(&cq->lock);
 loop:
@@ -746,7 +764,7 @@ loop:
 
 		switch (cq_desc->cqe_type) {
 		case CQE_TYPE_RX:
-			nicvf_rcv_pkt_handler(netdev, napi, cq_desc);
+			nicvf_rcv_pkt_handler(netdev, napi, cq_desc, sq);
 			work_done++;
 		break;
 		case CQE_TYPE_SEND:
@@ -773,17 +791,26 @@ loop:
 		goto loop;
 
 done:
-	sq = &nic->qs->sq[cq_idx];
 	/* Update SQ's descriptor free count */
 	if (subdesc_cnt)
 		nicvf_put_sq_desc(sq, subdesc_cnt);
 
+	txq_idx = nicvf_netdev_qidx(nic, cq_idx);
+	/* Handle XDP TX queues */
+	if (nic->pnicvf->xdp_prog) {
+		if (txq_idx < nic->pnicvf->xdp_tx_queues) {
+			nicvf_xdp_sq_doorbell(nic, sq, cq_idx);
+			goto out;
+		}
+		nic = nic->pnicvf;
+		txq_idx -= nic->pnicvf->xdp_tx_queues;
+	}
+
 	/* Wakeup TXQ if its stopped earlier due to SQ full */
 	if (tx_done ||
 	    (atomic_read(&sq->free_cnt) >= MIN_SQ_DESC_PER_PKT_XMIT)) {
 		netdev = nic->pnicvf->netdev;
-		txq = netdev_get_tx_queue(netdev,
-					  nicvf_netdev_qidx(nic, cq_idx));
+		txq = netdev_get_tx_queue(netdev, txq_idx);
 		if (tx_pkts)
 			netdev_tx_completed_queue(txq, tx_pkts, tx_bytes);
 
@@ -796,10 +823,11 @@ done:
 			if (netif_msg_tx_err(nic))
 				netdev_warn(netdev,
 					    "%s: Transmit queue wakeup SQ%d\n",
-					    netdev->name, cq_idx);
+					    netdev->name, txq_idx);
 		}
 	}
 
+out:
 	spin_unlock_bh(&cq->lock);
 	return work_done;
 }
@@ -1115,6 +1143,13 @@ static netdev_tx_t nicvf_xmit(struct sk_buff *skb, struct net_device *netdev)
 		return NETDEV_TX_OK;
 	}
 
+	/* In XDP case, initial HW tx queues are used for XDP,
+	 * but stack's queue mapping starts at '0', so skip the
+	 * Tx queues attached to Rx queues for XDP.
+	 */
+	if (nic->xdp_prog)
+		qid += nic->xdp_tx_queues;
+
 	snic = nic;
 	/* Get secondary Qset's SQ structure */
 	if (qid >= MAX_SND_QUEUES_PER_QS) {
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index 5009f497e64f..ec234b626fe3 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -19,6 +19,8 @@
 #include "q_struct.h"
 #include "nicvf_queues.h"
 
+static inline void nicvf_sq_add_gather_subdesc(struct snd_queue *sq, int qentry,
+					       int size, u64 data);
 static void nicvf_get_page(struct nicvf *nic)
 {
 	if (!nic->rb_pageref || !nic->rb_page)
@@ -456,7 +458,7 @@ static void nicvf_free_cmp_queue(struct nicvf *nic, struct cmp_queue *cq)
 
 /* Initialize transmit queue */
 static int nicvf_init_snd_queue(struct nicvf *nic,
-				struct snd_queue *sq, int q_len)
+				struct snd_queue *sq, int q_len, int qidx)
 {
 	int err;
 
@@ -469,17 +471,38 @@ static int nicvf_init_snd_queue(struct nicvf *nic,
 	sq->skbuff = kcalloc(q_len, sizeof(u64), GFP_KERNEL);
 	if (!sq->skbuff)
 		return -ENOMEM;
+
 	sq->head = 0;
 	sq->tail = 0;
-	atomic_set(&sq->free_cnt, q_len - 1);
 	sq->thresh = SND_QUEUE_THRESH;
 
-	/* Preallocate memory for TSO segment's header */
-	sq->tso_hdrs = dma_alloc_coherent(&nic->pdev->dev,
-					  q_len * TSO_HEADER_SIZE,
-					  &sq->tso_hdrs_phys, GFP_KERNEL);
-	if (!sq->tso_hdrs)
-		return -ENOMEM;
+	/* Check if this SQ is a XDP TX queue */
+	if (nic->sqs_mode)
+		qidx += ((nic->sqs_id + 1) * MAX_SND_QUEUES_PER_QS);
+	if (qidx < nic->pnicvf->xdp_tx_queues) {
+		/* Alloc memory to save page pointers for XDP_TX */
+		sq->xdp_page = kcalloc(q_len, sizeof(u64), GFP_KERNEL);
+		if (!sq->xdp_page)
+			return -ENOMEM;
+		sq->xdp_desc_cnt = 0;
+		sq->xdp_free_cnt = q_len - 1;
+		sq->is_xdp = true;
+	} else {
+		sq->xdp_page = NULL;
+		sq->xdp_desc_cnt = 0;
+		sq->xdp_free_cnt = 0;
+		sq->is_xdp = false;
+
+		atomic_set(&sq->free_cnt, q_len - 1);
+
+		/* Preallocate memory for TSO segment's header */
+		sq->tso_hdrs = dma_alloc_coherent(&nic->pdev->dev,
+						  q_len * TSO_HEADER_SIZE,
+						  &sq->tso_hdrs_phys,
+						  GFP_KERNEL);
+		if (!sq->tso_hdrs)
+			return -ENOMEM;
+	}
 
 	return 0;
 }
@@ -505,6 +528,7 @@ void nicvf_unmap_sndq_buffers(struct nicvf *nic, struct snd_queue *sq,
 static void nicvf_free_snd_queue(struct nicvf *nic, struct snd_queue *sq)
 {
 	struct sk_buff *skb;
+	struct page *page;
 	struct sq_hdr_subdesc *hdr;
 	struct sq_hdr_subdesc *tso_sqe;
 
@@ -522,8 +546,15 @@ static void nicvf_free_snd_queue(struct nicvf *nic, struct snd_queue *sq)
 	smp_rmb();
 	while (sq->head != sq->tail) {
 		skb = (struct sk_buff *)sq->skbuff[sq->head];
-		if (!skb)
+		if (!skb || !sq->xdp_page)
+			goto next;
+
+		page = (struct page *)sq->xdp_page[sq->head];
+		if (!page)
 			goto next;
+		else
+			put_page(page);
+
 		hdr = (struct sq_hdr_subdesc *)GET_SQ_DESC(sq, sq->head);
 		/* Check for dummy descriptor used for HW TSO offload on 88xx */
 		if (hdr->dont_send) {
@@ -536,12 +567,14 @@ static void nicvf_free_snd_queue(struct nicvf *nic, struct snd_queue *sq)
 			nicvf_unmap_sndq_buffers(nic, sq, sq->head,
 						 hdr->subdesc_cnt);
 		}
-		dev_kfree_skb_any(skb);
+		if (skb)
+			dev_kfree_skb_any(skb);
 next:
 		sq->head++;
 		sq->head &= (sq->dmem.q_len - 1);
 	}
 	kfree(sq->skbuff);
+	kfree(sq->xdp_page);
 	nicvf_free_q_desc_mem(nic, &sq->dmem);
 }
 
@@ -932,7 +965,7 @@ static int nicvf_alloc_resources(struct nicvf *nic)
 
 	/* Alloc send queue */
 	for (qidx = 0; qidx < qs->sq_cnt; qidx++) {
-		if (nicvf_init_snd_queue(nic, &qs->sq[qidx], qs->sq_len))
+		if (nicvf_init_snd_queue(nic, &qs->sq[qidx], qs->sq_len, qidx))
 			goto alloc_fail;
 	}
 
@@ -1035,7 +1068,10 @@ static inline int nicvf_get_sq_desc(struct snd_queue *sq, int desc_cnt)
 	int qentry;
 
 	qentry = sq->tail;
-	atomic_sub(desc_cnt, &sq->free_cnt);
+	if (!sq->is_xdp)
+		atomic_sub(desc_cnt, &sq->free_cnt);
+	else
+		sq->xdp_free_cnt -= desc_cnt;
 	sq->tail += desc_cnt;
 	sq->tail &= (sq->dmem.q_len - 1);
 
@@ -1053,7 +1089,10 @@ static inline void nicvf_rollback_sq_desc(struct snd_queue *sq,
 /* Free descriptor back to SQ for future use */
 void nicvf_put_sq_desc(struct snd_queue *sq, int desc_cnt)
 {
-	atomic_add(desc_cnt, &sq->free_cnt);
+	if (!sq->is_xdp)
+		atomic_add(desc_cnt, &sq->free_cnt);
+	else
+		sq->xdp_free_cnt += desc_cnt;
 	sq->head += desc_cnt;
 	sq->head &= (sq->dmem.q_len - 1);
 }
@@ -1111,6 +1150,58 @@ void nicvf_sq_free_used_descs(struct net_device *netdev, struct snd_queue *sq,
 	}
 }
 
+/* XDP Transmit APIs */
+void nicvf_xdp_sq_doorbell(struct nicvf *nic,
+			   struct snd_queue *sq, int sq_num)
+{
+	if (!sq->xdp_desc_cnt)
+		return;
+
+	/* make sure all memory stores are done before ringing doorbell */
+	wmb();
+
+	/* Inform HW to xmit all TSO segments */
+	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_DOOR,
+			      sq_num, sq->xdp_desc_cnt);
+	sq->xdp_desc_cnt = 0;
+}
+
+static inline void
+nicvf_xdp_sq_add_hdr_subdesc(struct snd_queue *sq, int qentry,
+			     int subdesc_cnt, u64 data, int len)
+{
+	struct sq_hdr_subdesc *hdr;
+
+	hdr = (struct sq_hdr_subdesc *)GET_SQ_DESC(sq, qentry);
+	memset(hdr, 0, SND_QUEUE_DESC_SIZE);
+	hdr->subdesc_type = SQ_DESC_TYPE_HEADER;
+	hdr->subdesc_cnt = subdesc_cnt;
+	hdr->tot_len = len;
+	hdr->post_cqe = 1;
+	sq->xdp_page[qentry] = (u64)virt_to_page((void *)data);
+}
+
+int nicvf_xdp_sq_append_pkt(struct nicvf *nic, struct snd_queue *sq,
+			    u64 bufaddr, u64 dma_addr, u16 len)
+{
+	int subdesc_cnt = MIN_SQ_DESC_PER_PKT_XMIT;
+	int qentry;
+
+	if (subdesc_cnt > sq->xdp_free_cnt)
+		return 0;
+
+	qentry = nicvf_get_sq_desc(sq, subdesc_cnt);
+
+	nicvf_xdp_sq_add_hdr_subdesc(sq, qentry, subdesc_cnt - 1, bufaddr, len);
+
+	qentry = nicvf_get_nxt_sqentry(sq, qentry);
+	nicvf_sq_add_gather_subdesc(sq, qentry, len, dma_addr);
+
+	sq->xdp_desc_cnt += subdesc_cnt;
+
+	return 1;
+}
+
 /* Calculate no of SQ subdescriptors needed to transmit all
  * segments of this TSO packet.
  * Taken from 'Tilera network driver' with a minor modification.
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
index db04c0e33c6c..a07d5b4d5ce2 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
@@ -271,6 +271,10 @@ struct snd_queue {
 	u32		tail;
 	u64		*skbuff;
 	void		*desc;
+	u64		*xdp_page;
+	u16		xdp_desc_cnt;
+	u16		xdp_free_cnt;
+	bool		is_xdp;
 
 #define	TSO_HEADER_SIZE	128
 	/* For TSO segment's header */
@@ -339,6 +343,9 @@ void nicvf_sq_free_used_descs(struct net_device *netdev,
 			      struct snd_queue *sq, int qidx);
 int nicvf_sq_append_skb(struct nicvf *nic, struct snd_queue *sq,
 			struct sk_buff *skb, u8 sq_num);
+int nicvf_xdp_sq_append_pkt(struct nicvf *nic, struct snd_queue *sq,
+			    u64 bufaddr, u64 dma_addr, u16 len);
+void nicvf_xdp_sq_doorbell(struct nicvf *nic, struct snd_queue *sq, int sq_num);
 
 struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic,
 				  struct cqe_rx_t *cqe_rx, bool xdp);