Merge branch 'dpaa2-eth-Introduce-XDP-support'

Ioana Ciocoi Radulescu says:

====================
dpaa2-eth: Introduce XDP support

Add support for XDP programs. Only XDP_PASS, XDP_DROP and XDP_TX
actions are supported for now. Frame header changes are also
allowed.

v2: - count the XDP packets in the rx/tx inteface stats
    - add message with the maximum supported MTU value for XDP
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 350 insertions, 38 deletions

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
index 640967a4d50d..be841718eb49 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -13,7 +13,8 @@
 #include <linux/iommu.h>
 #include <linux/net_tstamp.h>
 #include <linux/fsl/mc.h>
-
+#include <linux/bpf.h>
+#include <linux/bpf_trace.h>
 #include <net/sock.h>
 
 #include "dpaa2-eth.h"
@@ -86,7 +87,7 @@ static void free_rx_fd(struct dpaa2_eth_priv *priv,
 		addr = dpaa2_sg_get_addr(&sgt[i]);
 		sg_vaddr = dpaa2_iova_to_virt(priv->iommu_domain, addr);
 		dma_unmap_single(dev, addr, DPAA2_ETH_RX_BUF_SIZE,
-				 DMA_FROM_DEVICE);
+				 DMA_BIDIRECTIONAL);
 
 		skb_free_frag(sg_vaddr);
 		if (dpaa2_sg_is_final(&sgt[i]))
@@ -144,7 +145,7 @@ static struct sk_buff *build_frag_skb(struct dpaa2_eth_priv *priv,
 		sg_addr = dpaa2_sg_get_addr(sge);
 		sg_vaddr = dpaa2_iova_to_virt(priv->iommu_domain, sg_addr);
 		dma_unmap_single(dev, sg_addr, DPAA2_ETH_RX_BUF_SIZE,
-				 DMA_FROM_DEVICE);
+				 DMA_BIDIRECTIONAL);
 
 		sg_length = dpaa2_sg_get_len(sge);
 
@@ -199,6 +200,141 @@ static struct sk_buff *build_frag_skb(struct dpaa2_eth_priv *priv,
 	return skb;
 }
 
+/* Free buffers acquired from the buffer pool or which were meant to
+ * be released in the pool
+ */
+static void free_bufs(struct dpaa2_eth_priv *priv, u64 *buf_array, int count)
+{
+	struct device *dev = priv->net_dev->dev.parent;
+	void *vaddr;
+	int i;
+
+	for (i = 0; i < count; i++) {
+		vaddr = dpaa2_iova_to_virt(priv->iommu_domain, buf_array[i]);
+		dma_unmap_single(dev, buf_array[i], DPAA2_ETH_RX_BUF_SIZE,
+				 DMA_BIDIRECTIONAL);
+		skb_free_frag(vaddr);
+	}
+}
+
+static void xdp_release_buf(struct dpaa2_eth_priv *priv,
+			    struct dpaa2_eth_channel *ch,
+			    dma_addr_t addr)
+{
+	int err;
+
+	ch->xdp.drop_bufs[ch->xdp.drop_cnt++] = addr;
+	if (ch->xdp.drop_cnt < DPAA2_ETH_BUFS_PER_CMD)
+		return;
+
+	while ((err = dpaa2_io_service_release(ch->dpio, priv->bpid,
+					       ch->xdp.drop_bufs,
+					       ch->xdp.drop_cnt)) == -EBUSY)
+		cpu_relax();
+
+	if (err) {
+		free_bufs(priv, ch->xdp.drop_bufs, ch->xdp.drop_cnt);
+		ch->buf_count -= ch->xdp.drop_cnt;
+	}
+
+	ch->xdp.drop_cnt = 0;
+}
+
+static int xdp_enqueue(struct dpaa2_eth_priv *priv, struct dpaa2_fd *fd,
+		       void *buf_start, u16 queue_id)
+{
+	struct dpaa2_eth_fq *fq;
+	struct dpaa2_faead *faead;
+	u32 ctrl, frc;
+	int i, err;
+
+	/* Mark the egress frame hardware annotation area as valid */
+	frc = dpaa2_fd_get_frc(fd);
+	dpaa2_fd_set_frc(fd, frc | DPAA2_FD_FRC_FAEADV);
+	dpaa2_fd_set_ctrl(fd, DPAA2_FD_CTRL_ASAL);
+
+	/* Instruct hardware to release the FD buffer directly into
+	 * the buffer pool once transmission is completed, instead of
+	 * sending a Tx confirmation frame to us
+	 */
+	ctrl = DPAA2_FAEAD_A4V | DPAA2_FAEAD_A2V | DPAA2_FAEAD_EBDDV;
+	faead = dpaa2_get_faead(buf_start, false);
+	faead->ctrl = cpu_to_le32(ctrl);
+	faead->conf_fqid = 0;
+
+	fq = &priv->fq[queue_id];
+	for (i = 0; i < DPAA2_ETH_ENQUEUE_RETRIES; i++) {
+		err = dpaa2_io_service_enqueue_qd(fq->channel->dpio,
+						  priv->tx_qdid, 0,
+						  fq->tx_qdbin, fd);
+		if (err != -EBUSY)
+			break;
+	}
+
+	return err;
+}
+
+static u32 run_xdp(struct dpaa2_eth_priv *priv,
+		   struct dpaa2_eth_channel *ch,
+		   struct dpaa2_eth_fq *rx_fq,
+		   struct dpaa2_fd *fd, void *vaddr)
+{
+	dma_addr_t addr = dpaa2_fd_get_addr(fd);
+	struct rtnl_link_stats64 *percpu_stats;
+	struct bpf_prog *xdp_prog;
+	struct xdp_buff xdp;
+	u32 xdp_act = XDP_PASS;
+	int err;
+
+	percpu_stats = this_cpu_ptr(priv->percpu_stats);
+
+	rcu_read_lock();
+
+	xdp_prog = READ_ONCE(ch->xdp.prog);
+	if (!xdp_prog)
+		goto out;
+
+	xdp.data = vaddr + dpaa2_fd_get_offset(fd);
+	xdp.data_end = xdp.data + dpaa2_fd_get_len(fd);
+	xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
+	xdp_set_data_meta_invalid(&xdp);
+
+	xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp);
+
+	/* xdp.data pointer may have changed */
+	dpaa2_fd_set_offset(fd, xdp.data - vaddr);
+	dpaa2_fd_set_len(fd, xdp.data_end - xdp.data);
+
+	switch (xdp_act) {
+	case XDP_PASS:
+		break;
+	case XDP_TX:
+		err = xdp_enqueue(priv, fd, vaddr, rx_fq->flowid);
+		if (err) {
+			xdp_release_buf(priv, ch, addr);
+			percpu_stats->tx_errors++;
+			ch->stats.xdp_tx_err++;
+		} else {
+			percpu_stats->tx_packets++;
+			percpu_stats->tx_bytes += dpaa2_fd_get_len(fd);
+			ch->stats.xdp_tx++;
+		}
+		break;
+	default:
+		bpf_warn_invalid_xdp_action(xdp_act);
+	case XDP_ABORTED:
+		trace_xdp_exception(priv->net_dev, xdp_prog, xdp_act);
+	case XDP_DROP:
+		xdp_release_buf(priv, ch, addr);
+		ch->stats.xdp_drop++;
+		break;
+	}
+
+out:
+	rcu_read_unlock();
+	return xdp_act;
+}
+
 /* Main Rx frame processing routine */
 static void dpaa2_eth_rx(struct dpaa2_eth_priv *priv,
 			 struct dpaa2_eth_channel *ch,
@@ -215,12 +351,14 @@ static void dpaa2_eth_rx(struct dpaa2_eth_priv *priv,
 	struct dpaa2_fas *fas;
 	void *buf_data;
 	u32 status = 0;
+	u32 xdp_act;
 
 	/* Tracing point */
 	trace_dpaa2_rx_fd(priv->net_dev, fd);
 
 	vaddr = dpaa2_iova_to_virt(priv->iommu_domain, addr);
-	dma_unmap_single(dev, addr, DPAA2_ETH_RX_BUF_SIZE, DMA_FROM_DEVICE);
+	dma_sync_single_for_cpu(dev, addr, DPAA2_ETH_RX_BUF_SIZE,
+				DMA_BIDIRECTIONAL);
 
 	fas = dpaa2_get_fas(vaddr, false);
 	prefetch(fas);
@@ -231,8 +369,21 @@ static void dpaa2_eth_rx(struct dpaa2_eth_priv *priv,
 	percpu_extras = this_cpu_ptr(priv->percpu_extras);
 
 	if (fd_format == dpaa2_fd_single) {
+		xdp_act = run_xdp(priv, ch, fq, (struct dpaa2_fd *)fd, vaddr);
+		if (xdp_act != XDP_PASS) {
+			percpu_stats->rx_packets++;
+			percpu_stats->rx_bytes += dpaa2_fd_get_len(fd);
+			return;
+		}
+
+		dma_unmap_single(dev, addr, DPAA2_ETH_RX_BUF_SIZE,
+				 DMA_BIDIRECTIONAL);
 		skb = build_linear_skb(ch, fd, vaddr);
 	} else if (fd_format == dpaa2_fd_sg) {
+		WARN_ON(priv->xdp_prog);
+
+		dma_unmap_single(dev, addr, DPAA2_ETH_RX_BUF_SIZE,
+				 DMA_BIDIRECTIONAL);
 		skb = build_frag_skb(priv, ch, buf_data);
 		skb_free_frag(vaddr);
 		percpu_extras->rx_sg_frames++;
@@ -319,7 +470,6 @@ static int consume_frames(struct dpaa2_eth_channel *ch,
 		return 0;
 
 	fq->stats.frames += cleaned;
-	ch->stats.frames += cleaned;
 
 	/* A dequeue operation only pulls frames from a single queue
 	 * into the store. Return the frame queue as an out param.
@@ -743,23 +893,6 @@ static int set_tx_csum(struct dpaa2_eth_priv *priv, bool enable)
 	return 0;
 }
 
-/* Free buffers acquired from the buffer pool or which were meant to
- * be released in the pool
- */
-static void free_bufs(struct dpaa2_eth_priv *priv, u64 *buf_array, int count)
-{
-	struct device *dev = priv->net_dev->dev.parent;
-	void *vaddr;
-	int i;
-
-	for (i = 0; i < count; i++) {
-		vaddr = dpaa2_iova_to_virt(priv->iommu_domain, buf_array[i]);
-		dma_unmap_single(dev, buf_array[i], DPAA2_ETH_RX_BUF_SIZE,
-				 DMA_FROM_DEVICE);
-		skb_free_frag(vaddr);
-	}
-}
-
 /* Perform a single release command to add buffers
  * to the specified buffer pool
  */
@@ -783,7 +916,7 @@ static int add_bufs(struct dpaa2_eth_priv *priv,
 		buf = PTR_ALIGN(buf, priv->rx_buf_align);
 
 		addr = dma_map_single(dev, buf, DPAA2_ETH_RX_BUF_SIZE,
-				      DMA_FROM_DEVICE);
+				      DMA_BIDIRECTIONAL);
 		if (unlikely(dma_mapping_error(dev, addr)))
 			goto err_map;
 
@@ -1427,6 +1560,174 @@ static int dpaa2_eth_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 	return -EINVAL;
 }
 
+static bool xdp_mtu_valid(struct dpaa2_eth_priv *priv, int mtu)
+{
+	int mfl, linear_mfl;
+
+	mfl = DPAA2_ETH_L2_MAX_FRM(mtu);
+	linear_mfl = DPAA2_ETH_RX_BUF_SIZE - DPAA2_ETH_RX_HWA_SIZE -
+		     dpaa2_eth_rx_head_room(priv) - XDP_PACKET_HEADROOM;
+
+	if (mfl > linear_mfl) {
+		netdev_warn(priv->net_dev, "Maximum MTU for XDP is %d\n",
+			    linear_mfl - VLAN_ETH_HLEN);
+		return false;
+	}
+
+	return true;
+}
+
+static int set_rx_mfl(struct dpaa2_eth_priv *priv, int mtu, bool has_xdp)
+{
+	int mfl, err;
+
+	/* We enforce a maximum Rx frame length based on MTU only if we have
+	 * an XDP program attached (in order to avoid Rx S/G frames).
+	 * Otherwise, we accept all incoming frames as long as they are not
+	 * larger than maximum size supported in hardware
+	 */
+	if (has_xdp)
+		mfl = DPAA2_ETH_L2_MAX_FRM(mtu);
+	else
+		mfl = DPAA2_ETH_MFL;
+
+	err = dpni_set_max_frame_length(priv->mc_io, 0, priv->mc_token, mfl);
+	if (err) {
+		netdev_err(priv->net_dev, "dpni_set_max_frame_length failed\n");
+		return err;
+	}
+
+	return 0;
+}
+
+static int dpaa2_eth_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct dpaa2_eth_priv *priv = netdev_priv(dev);
+	int err;
+
+	if (!priv->xdp_prog)
+		goto out;
+
+	if (!xdp_mtu_valid(priv, new_mtu))
+		return -EINVAL;
+
+	err = set_rx_mfl(priv, new_mtu, true);
+	if (err)
+		return err;
+
+out:
+	dev->mtu = new_mtu;
+	return 0;
+}
+
+static int update_rx_buffer_headroom(struct dpaa2_eth_priv *priv, bool has_xdp)
+{
+	struct dpni_buffer_layout buf_layout = {0};
+	int err;
+
+	err = dpni_get_buffer_layout(priv->mc_io, 0, priv->mc_token,
+				     DPNI_QUEUE_RX, &buf_layout);
+	if (err) {
+		netdev_err(priv->net_dev, "dpni_get_buffer_layout failed\n");
+		return err;
+	}
+
+	/* Reserve extra headroom for XDP header size changes */
+	buf_layout.data_head_room = dpaa2_eth_rx_head_room(priv) +
+				    (has_xdp ? XDP_PACKET_HEADROOM : 0);
+	buf_layout.options = DPNI_BUF_LAYOUT_OPT_DATA_HEAD_ROOM;
+	err = dpni_set_buffer_layout(priv->mc_io, 0, priv->mc_token,
+				     DPNI_QUEUE_RX, &buf_layout);
+	if (err) {
+		netdev_err(priv->net_dev, "dpni_set_buffer_layout failed\n");
+		return err;
+	}
+
+	return 0;
+}
+
+static int setup_xdp(struct net_device *dev, struct bpf_prog *prog)
+{
+	struct dpaa2_eth_priv *priv = netdev_priv(dev);
+	struct dpaa2_eth_channel *ch;
+	struct bpf_prog *old;
+	bool up, need_update;
+	int i, err;
+
+	if (prog && !xdp_mtu_valid(priv, dev->mtu))
+		return -EINVAL;
+
+	if (prog) {
+		prog = bpf_prog_add(prog, priv->num_channels);
+		if (IS_ERR(prog))
+			return PTR_ERR(prog);
+	}
+
+	up = netif_running(dev);
+	need_update = (!!priv->xdp_prog != !!prog);
+
+	if (up)
+		dpaa2_eth_stop(dev);
+
+	/* While in xdp mode, enforce a maximum Rx frame size based on MTU.
+	 * Also, when switching between xdp/non-xdp modes we need to reconfigure
+	 * our Rx buffer layout. Buffer pool was drained on dpaa2_eth_stop,
+	 * so we are sure no old format buffers will be used from now on.
+	 */
+	if (need_update) {
+		err = set_rx_mfl(priv, dev->mtu, !!prog);
+		if (err)
+			goto out_err;
+		err = update_rx_buffer_headroom(priv, !!prog);
+		if (err)
+			goto out_err;
+	}
+
+	old = xchg(&priv->xdp_prog, prog);
+	if (old)
+		bpf_prog_put(old);
+
+	for (i = 0; i < priv->num_channels; i++) {
+		ch = priv->channel[i];
+		old = xchg(&ch->xdp.prog, prog);
+		if (old)
+			bpf_prog_put(old);
+	}
+
+	if (up) {
+		err = dpaa2_eth_open(dev);
+		if (err)
+			return err;
+	}
+
+	return 0;
+
+out_err:
+	if (prog)
+		bpf_prog_sub(prog, priv->num_channels);
+	if (up)
+		dpaa2_eth_open(dev);
+
+	return err;
+}
+
+static int dpaa2_eth_xdp(struct net_device *dev, struct netdev_bpf *xdp)
+{
+	struct dpaa2_eth_priv *priv = netdev_priv(dev);
+
+	switch (xdp->command) {
+	case XDP_SETUP_PROG:
+		return setup_xdp(dev, xdp->prog);
+	case XDP_QUERY_PROG:
+		xdp->prog_id = priv->xdp_prog ? priv->xdp_prog->aux->id : 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static const struct net_device_ops dpaa2_eth_ops = {
 	.ndo_open = dpaa2_eth_open,
 	.ndo_start_xmit = dpaa2_eth_tx,
@@ -1436,6 +1737,8 @@ static const struct net_device_ops dpaa2_eth_ops = {
 	.ndo_set_rx_mode = dpaa2_eth_set_rx_mode,
 	.ndo_set_features = dpaa2_eth_set_features,
 	.ndo_do_ioctl = dpaa2_eth_ioctl,
+	.ndo_change_mtu = dpaa2_eth_change_mtu,
+	.ndo_bpf = dpaa2_eth_xdp,
 };
 
 static void cdan_cb(struct dpaa2_io_notification_ctx *ctx)
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
index 16545e9386cd..69c965de192b 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
@@ -139,7 +139,9 @@ struct dpaa2_faead {
 };
 
 #define DPAA2_FAEAD_A2V			0x20000000
+#define DPAA2_FAEAD_A4V			0x08000000
 #define DPAA2_FAEAD_UPDV		0x00001000
+#define DPAA2_FAEAD_EBDDV		0x00002000
 #define DPAA2_FAEAD_UPD			0x00000010
 
 /* Accessors for the hardware annotation fields that we use */
@@ -243,12 +245,14 @@ struct dpaa2_eth_fq_stats {
 struct dpaa2_eth_ch_stats {
 	/* Volatile dequeues retried due to portal busy */
 	__u64 dequeue_portal_busy;
-	/* Number of CDANs; useful to estimate avg NAPI len */
-	__u64 cdan;
-	/* Number of frames received on queues from this channel */
-	__u64 frames;
 	/* Pull errors */
 	__u64 pull_err;
+	/* Number of CDANs; useful to estimate avg NAPI len */
+	__u64 cdan;
+	/* XDP counters */
+	__u64 xdp_drop;
+	__u64 xdp_tx;
+	__u64 xdp_tx_err;
 };
 
 /* Maximum number of queues associated with a DPNI */
@@ -283,6 +287,12 @@ struct dpaa2_eth_fq {
 	struct dpaa2_eth_fq_stats stats;
 };
 
+struct dpaa2_eth_ch_xdp {
+	struct bpf_prog *prog;
+	u64 drop_bufs[DPAA2_ETH_BUFS_PER_CMD];
+	int drop_cnt;
+};
+
 struct dpaa2_eth_channel {
 	struct dpaa2_io_notification_ctx nctx;
 	struct fsl_mc_device *dpcon;
@@ -294,6 +304,7 @@ struct dpaa2_eth_channel {
 	struct dpaa2_eth_priv *priv;
 	int buf_count;
 	struct dpaa2_eth_ch_stats stats;
+	struct dpaa2_eth_ch_xdp xdp;
 };
 
 struct dpaa2_eth_dist_fields {
@@ -353,6 +364,7 @@ struct dpaa2_eth_priv {
 	u64 rx_hash_fields;
 	struct dpaa2_eth_cls_rule *cls_rules;
 	u8 rx_cls_enabled;
+	struct bpf_prog *xdp_prog;
 };
 
 #define DPAA2_RXH_SUPPORTED	(RXH_L2DA | RXH_VLAN | RXH_L3_PROTO \
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
index 26bd5a2bd8ed..0c831bffeb92 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
@@ -45,6 +45,9 @@ static char dpaa2_ethtool_extras[][ETH_GSTRING_LEN] = {
 	"[drv] dequeue portal busy",
 	"[drv] channel pull errors",
 	"[drv] cdan",
+	"[drv] xdp drop",
+	"[drv] xdp tx",
+	"[drv] xdp tx errors",
 };
 
 #define DPAA2_ETH_NUM_EXTRA_STATS	ARRAY_SIZE(dpaa2_ethtool_extras)
@@ -174,8 +177,6 @@ static void dpaa2_eth_get_ethtool_stats(struct net_device *net_dev,
 	int j, k, err;
 	int num_cnt;
 	union dpni_statistics dpni_stats;
-	u64 cdan = 0;
-	u64 portal_busy = 0, pull_err = 0;
 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
 	struct dpaa2_eth_drv_stats *extras;
 	struct dpaa2_eth_ch_stats *ch_stats;
@@ -212,16 +213,12 @@ static void dpaa2_eth_get_ethtool_stats(struct net_device *net_dev,
 	}
 	i += j;
 
-	for (j = 0; j < priv->num_channels; j++) {
-		ch_stats = &priv->channel[j]->stats;
-		cdan += ch_stats->cdan;
-		portal_busy += ch_stats->dequeue_portal_busy;
-		pull_err += ch_stats->pull_err;
+	/* Per-channel stats */
+	for (k = 0; k < priv->num_channels; k++) {
+		ch_stats = &priv->channel[k]->stats;
+		for (j = 0; j < sizeof(*ch_stats) / sizeof(__u64); j++)
+			*((__u64 *)data + i + j) += *((__u64 *)ch_stats + j);
 	}
-
-	*(data + i++) = portal_busy;
-	*(data + i++) = pull_err;
-	*(data + i++) = cdan;
 }
 
 static int prep_eth_rule(struct ethhdr *eth_value, struct ethhdr *eth_mask,