[net-next,v3,6/7] net: lan966x: Add support for XDP_TX

Message ID 20221121212850.3212649-7-horatiu.vultur@microchip.com
State New
Headers
Series net: lan966x: Extend xdp support |

Commit Message

Horatiu Vultur Nov. 21, 2022, 9:28 p.m. UTC
  Extend lan966x XDP support with the action XDP_TX. In this case when the
received buffer needs to execute XDP_TX, the buffer will be moved to the
TX buffers. So a new RX buffer will be allocated.
When the TX finish with the frame, it would give back the buffer to the
page pool.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
---
 .../ethernet/microchip/lan966x/lan966x_fdma.c | 78 +++++++++++++++++--
 .../ethernet/microchip/lan966x/lan966x_main.c |  4 +-
 .../ethernet/microchip/lan966x/lan966x_main.h |  8 ++
 .../ethernet/microchip/lan966x/lan966x_xdp.c  |  8 ++
 4 files changed, 90 insertions(+), 8 deletions(-)
  

Comments

Alexander Lobakin Nov. 22, 2022, 4:56 p.m. UTC | #1
From: Horatiu Vultur <horatiu.vultur@microchip.com>
Date: Mon, 21 Nov 2022 22:28:49 +0100

> Extend lan966x XDP support with the action XDP_TX. In this case when the
> received buffer needs to execute XDP_TX, the buffer will be moved to the
> TX buffers. So a new RX buffer will be allocated.
> When the TX finish with the frame, it would give back the buffer to the
> page pool.
> 
> Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> ---
>  .../ethernet/microchip/lan966x/lan966x_fdma.c | 78 +++++++++++++++++--
>  .../ethernet/microchip/lan966x/lan966x_main.c |  4 +-
>  .../ethernet/microchip/lan966x/lan966x_main.h |  8 ++
>  .../ethernet/microchip/lan966x/lan966x_xdp.c  |  8 ++
>  4 files changed, 90 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> index f8287a6a86ed5..b14fdb8e15e22 100644
> --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> @@ -411,12 +411,18 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
>  		dcb_buf->dev->stats.tx_bytes += dcb_buf->len;
>  
>  		dcb_buf->used = false;
> -		dma_unmap_single(lan966x->dev,
> -				 dcb_buf->dma_addr,
> -				 dcb_buf->len,
> -				 DMA_TO_DEVICE);
> -		if (!dcb_buf->ptp)
> -			dev_kfree_skb_any(dcb_buf->skb);
> +		if (dcb_buf->skb) {
> +			dma_unmap_single(lan966x->dev,
> +					 dcb_buf->dma_addr,
> +					 dcb_buf->len,
> +					 DMA_TO_DEVICE);
> +
> +			if (!dcb_buf->ptp)
> +				dev_kfree_skb_any(dcb_buf->skb);

Damn, forgot to remind you you wanted to switch to
napi_consume_skb() :s

> +		}
> +
> +		if (dcb_buf->xdpf)
> +			xdp_return_frame_rx_napi(dcb_buf->xdpf);
>  
>  		clear = true;
>  	}

[...]

> -- 
> 2.38.0

Thanks,
Olek
  
Horatiu Vultur Nov. 22, 2022, 9:38 p.m. UTC | #2
The 11/22/2022 17:56, Alexander Lobakin wrote:
> 
> From: Horatiu Vultur <horatiu.vultur@microchip.com>
> Date: Mon, 21 Nov 2022 22:28:49 +0100
> 
> > Extend lan966x XDP support with the action XDP_TX. In this case when the
> > received buffer needs to execute XDP_TX, the buffer will be moved to the
> > TX buffers. So a new RX buffer will be allocated.
> > When the TX finish with the frame, it would give back the buffer to the
> > page pool.
> >
> > Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> > ---
> >  .../ethernet/microchip/lan966x/lan966x_fdma.c | 78 +++++++++++++++++--
> >  .../ethernet/microchip/lan966x/lan966x_main.c |  4 +-
> >  .../ethernet/microchip/lan966x/lan966x_main.h |  8 ++
> >  .../ethernet/microchip/lan966x/lan966x_xdp.c  |  8 ++
> >  4 files changed, 90 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> > index f8287a6a86ed5..b14fdb8e15e22 100644
> > --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> > +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> > @@ -411,12 +411,18 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
> >               dcb_buf->dev->stats.tx_bytes += dcb_buf->len;
> >
> >               dcb_buf->used = false;
> > -             dma_unmap_single(lan966x->dev,
> > -                              dcb_buf->dma_addr,
> > -                              dcb_buf->len,
> > -                              DMA_TO_DEVICE);
> > -             if (!dcb_buf->ptp)
> > -                     dev_kfree_skb_any(dcb_buf->skb);
> > +             if (dcb_buf->skb) {
> > +                     dma_unmap_single(lan966x->dev,
> > +                                      dcb_buf->dma_addr,
> > +                                      dcb_buf->len,
> > +                                      DMA_TO_DEVICE);
> > +
> > +                     if (!dcb_buf->ptp)
> > +                             dev_kfree_skb_any(dcb_buf->skb);
> 
> Damn, forgot to remind you you wanted to switch to
> napi_consume_skb() :s

Correct, I forgot to update this. Will do in the next series.

> 
> > +             }
> > +
> > +             if (dcb_buf->xdpf)
> > +                     xdp_return_frame_rx_napi(dcb_buf->xdpf);
> >
> >               clear = true;
> >       }
> 
> [...]
> 
> > --
> > 2.38.0
> 
> Thanks,
> Olek
  

Patch

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
index f8287a6a86ed5..b14fdb8e15e22 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
@@ -411,12 +411,18 @@  static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
 		dcb_buf->dev->stats.tx_bytes += dcb_buf->len;
 
 		dcb_buf->used = false;
-		dma_unmap_single(lan966x->dev,
-				 dcb_buf->dma_addr,
-				 dcb_buf->len,
-				 DMA_TO_DEVICE);
-		if (!dcb_buf->ptp)
-			dev_kfree_skb_any(dcb_buf->skb);
+		if (dcb_buf->skb) {
+			dma_unmap_single(lan966x->dev,
+					 dcb_buf->dma_addr,
+					 dcb_buf->len,
+					 DMA_TO_DEVICE);
+
+			if (!dcb_buf->ptp)
+				dev_kfree_skb_any(dcb_buf->skb);
+		}
+
+		if (dcb_buf->xdpf)
+			xdp_return_frame_rx_napi(dcb_buf->xdpf);
 
 		clear = true;
 	}
@@ -549,6 +555,9 @@  static int lan966x_fdma_napi_poll(struct napi_struct *napi, int weight)
 			lan966x_fdma_rx_free_page(rx);
 			lan966x_fdma_rx_advance_dcb(rx);
 			goto allocate_new;
+		case FDMA_TX:
+			lan966x_fdma_rx_advance_dcb(rx);
+			continue;
 		case FDMA_DROP:
 			lan966x_fdma_rx_free_page(rx);
 			lan966x_fdma_rx_advance_dcb(rx);
@@ -670,6 +679,62 @@  static void lan966x_fdma_tx_start(struct lan966x_tx *tx, int next_to_use)
 	tx->last_in_use = next_to_use;
 }
 
+int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
+			   struct xdp_frame *xdpf,
+			   struct page *page)
+{
+	struct lan966x *lan966x = port->lan966x;
+	struct lan966x_tx_dcb_buf *next_dcb_buf;
+	struct lan966x_tx *tx = &lan966x->tx;
+	dma_addr_t dma_addr;
+	int next_to_use;
+	__be32 *ifh;
+	int ret = 0;
+
+	spin_lock(&lan966x->tx_lock);
+
+	/* Get next index */
+	next_to_use = lan966x_fdma_get_next_dcb(tx);
+	if (next_to_use < 0) {
+		netif_stop_queue(port->dev);
+		ret = NETDEV_TX_BUSY;
+		goto out;
+	}
+
+	/* Generate new IFH */
+	ifh = page_address(page) + XDP_PACKET_HEADROOM;
+	memset(ifh, 0x0, sizeof(__be32) * IFH_LEN);
+	lan966x_ifh_set_bypass(ifh, 1);
+	lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port));
+
+	dma_addr = page_pool_get_dma_addr(page);
+	dma_sync_single_for_device(lan966x->dev, dma_addr + XDP_PACKET_HEADROOM,
+				   xdpf->len + IFH_LEN_BYTES,
+				   DMA_TO_DEVICE);
+
+	/* Setup next dcb */
+	lan966x_fdma_tx_setup_dcb(tx, next_to_use, xdpf->len + IFH_LEN_BYTES,
+				  dma_addr + XDP_PACKET_HEADROOM);
+
+	/* Fill up the buffer */
+	next_dcb_buf = &tx->dcbs_buf[next_to_use];
+	next_dcb_buf->skb = NULL;
+	next_dcb_buf->xdpf = xdpf;
+	next_dcb_buf->len = xdpf->len + IFH_LEN_BYTES;
+	next_dcb_buf->dma_addr = dma_addr;
+	next_dcb_buf->used = true;
+	next_dcb_buf->ptp = false;
+	next_dcb_buf->dev = port->dev;
+
+	/* Start the transmission */
+	lan966x_fdma_tx_start(tx, next_to_use);
+
+out:
+	spin_unlock(&lan966x->tx_lock);
+
+	return ret;
+}
+
 int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev)
 {
 	struct lan966x_port *port = netdev_priv(dev);
@@ -726,6 +791,7 @@  int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev)
 	/* Fill up the buffer */
 	next_dcb_buf = &tx->dcbs_buf[next_to_use];
 	next_dcb_buf->skb = skb;
+	next_dcb_buf->xdpf = NULL;
 	next_dcb_buf->len = skb->len;
 	next_dcb_buf->dma_addr = dma_addr;
 	next_dcb_buf->used = true;
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
index 42be5d0f1f015..0b7707306da26 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
@@ -302,13 +302,13 @@  static int lan966x_port_ifh_xmit(struct sk_buff *skb,
 	return NETDEV_TX_BUSY;
 }
 
-static void lan966x_ifh_set_bypass(void *ifh, u64 bypass)
+void lan966x_ifh_set_bypass(void *ifh, u64 bypass)
 {
 	packing(ifh, &bypass, IFH_POS_BYPASS + IFH_WID_BYPASS - 1,
 		IFH_POS_BYPASS, IFH_LEN * 4, PACK, 0);
 }
 
-static void lan966x_ifh_set_port(void *ifh, u64 bypass)
+void lan966x_ifh_set_port(void *ifh, u64 bypass)
 {
 	packing(ifh, &bypass, IFH_POS_DSTS + IFH_WID_DSTS - 1,
 		IFH_POS_DSTS, IFH_LEN * 4, PACK, 0);
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
index 7f1231b31c924..e303a12daf88a 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
@@ -105,11 +105,13 @@  enum macaccess_entry_type {
  * FDMA_PASS, frame is valid and can be used
  * FDMA_ERROR, something went wrong, stop getting more frames
  * FDMA_DROP, frame is dropped, but continue to get more frames
+ * FDMA_TX, frame is given to TX, but continue to get more frames
  */
 enum lan966x_fdma_action {
 	FDMA_PASS = 0,
 	FDMA_ERROR,
 	FDMA_DROP,
+	FDMA_TX,
 };
 
 struct lan966x_port;
@@ -175,6 +177,7 @@  struct lan966x_rx {
 struct lan966x_tx_dcb_buf {
 	struct net_device *dev;
 	struct sk_buff *skb;
+	struct xdp_frame *xdpf;
 	int len;
 	dma_addr_t dma_addr;
 	bool used;
@@ -360,6 +363,8 @@  bool lan966x_hw_offload(struct lan966x *lan966x, u32 port, struct sk_buff *skb);
 
 void lan966x_ifh_get_src_port(void *ifh, u64 *src_port);
 void lan966x_ifh_get_timestamp(void *ifh, u64 *timestamp);
+void lan966x_ifh_set_bypass(void *ifh, u64 bypass);
+void lan966x_ifh_set_port(void *ifh, u64 bypass);
 
 void lan966x_stats_get(struct net_device *dev,
 		       struct rtnl_link_stats64 *stats);
@@ -460,6 +465,9 @@  u32 lan966x_ptp_get_period_ps(void);
 int lan966x_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts);
 
 int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev);
+int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
+			   struct xdp_frame *frame,
+			   struct page *page);
 int lan966x_fdma_change_mtu(struct lan966x *lan966x);
 void lan966x_fdma_netdev_init(struct lan966x *lan966x, struct net_device *dev);
 void lan966x_fdma_netdev_deinit(struct lan966x *lan966x, struct net_device *dev);
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
index 05c5a28206558..5fd2f3b01e179 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
@@ -54,6 +54,7 @@  int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
 {
 	struct bpf_prog *xdp_prog = port->xdp_prog;
 	struct lan966x *lan966x = port->lan966x;
+	struct xdp_frame *xdpf;
 	struct xdp_buff xdp;
 	u32 act;
 
@@ -66,6 +67,13 @@  int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
 	switch (act) {
 	case XDP_PASS:
 		return FDMA_PASS;
+	case XDP_TX:
+		xdpf = xdp_convert_buff_to_frame(&xdp);
+		if (!xdpf)
+			return FDMA_DROP;
+
+		return lan966x_fdma_xmit_xdpf(port, xdpf, page) ?
+		       FDMA_DROP : FDMA_TX;
 	default:
 		bpf_warn_invalid_xdp_action(port->dev, xdp_prog, act);
 		fallthrough;