[PATCH net-next 00/10] bnxt_en: Add XDP support.

[PATCH net-next 00/10] bnxt_en: Add XDP support.

[Michael Chan]

The first 8 patches refactor the code (rx/tx code paths and ring logic)
and add the basic infrastructure to support XDP.  The 9th patch adds
basic ndo_xdp to support XDP_DROP and XDP_PASS only.  The 10th patch
completes the series with XDP_TX.

Michael Chan (10):
  bnxt_en: Refactor rx SKB function.
  bnxt_en: Add bp->rx_dir field for rx buffer DMA direction.
  bnxt_en: Add RX page mode support.
  bnxt_en: Use event bit map in RX path.
  bnxt_en: Centralize logic to reserve rings.
  bnxt_en: Add tx ring mapping logic.
  bnxt_en: Add a set of TX rings to support XDP.
  bnxt_en: Refactor tx completion path.
  bnxt_en: Add basic XDP support.
  bnxt_en: Add support for XDP_TX action.

 drivers/net/ethernet/broadcom/Kconfig             |   8 +
 drivers/net/ethernet/broadcom/bnxt/Makefile       |   2 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt.c         | 347 ++++++++++++++++------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h         |  56 +++-
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c |  53 ++--
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c     | 231 ++++++++++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h     |  30 ++
 7 files changed, 599 insertions(+), 128 deletions(-)
 create mode 100644 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
 create mode 100644 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h

-- 
1.8.3.1

[PATCH net-next 01/10] bnxt_en: Refactor rx SKB function.

[Michael Chan]

Minor refactoring of bnxt_rx_skb() so that it can easily be replaced by
a new function that handles packets in a single page.  Also, use a
function pointer bp->rx_skb_func() to switch to a new function when
we add the new mode in the next patch.

Add a new field data_ptr that points to the packet data in the
bnxt_sw_rx_bd structure.  The original data field is changed to void
pointer so that it can either hold the kmalloc'ed data or a page
pointer.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 42 ++++++++++++++++++++++---------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h | 11 ++++++--
 2 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 3d83b90..d419199 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -607,6 +607,7 @@ static inline int bnxt_alloc_rx_data(struct bnxt *bp,
 		return -ENOMEM;
 
 	rx_buf->data = data;
+	rx_buf->data_ptr = data + BNXT_RX_OFFSET;
 	dma_unmap_addr_set(rx_buf, mapping, mapping);
 
 	rxbd->rx_bd_haddr = cpu_to_le64(mapping);
@@ -615,7 +616,7 @@ static inline int bnxt_alloc_rx_data(struct bnxt *bp,
 }
 
 static void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons,
-			       u8 *data)
+			       void *data)
 {
 	u16 prod = rxr->rx_prod;
 	struct bnxt_sw_rx_bd *cons_rx_buf, *prod_rx_buf;
@@ -625,6 +626,7 @@ static void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons,
 	cons_rx_buf = &rxr->rx_buf_ring[cons];
 
 	prod_rx_buf->data = data;
+	prod_rx_buf->data_ptr = cons_rx_buf->data_ptr;
 
 	dma_unmap_addr_set(prod_rx_buf, mapping,
 			   dma_unmap_addr(cons_rx_buf, mapping));
@@ -755,7 +757,7 @@ static void bnxt_reuse_rx_agg_bufs(struct bnxt_napi *bnapi, u16 cp_cons,
 
 static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
 				   struct bnxt_rx_ring_info *rxr, u16 cons,
-				   u16 prod, u8 *data, dma_addr_t dma_addr,
+				   u16 prod, void *data, dma_addr_t dma_addr,
 				   unsigned int len)
 {
 	int err;
@@ -776,7 +778,7 @@ static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
 	}
 
 	skb_reserve(skb, BNXT_RX_OFFSET);
-	skb_put(skb, len);
+	skb_put(skb, len & 0xffff);
 	return skb;
 }
 
@@ -878,7 +880,8 @@ static inline struct sk_buff *bnxt_copy_skb(struct bnxt_napi *bnapi, u8 *data,
 	dma_sync_single_for_cpu(&pdev->dev, mapping,
 				bp->rx_copy_thresh, PCI_DMA_FROMDEVICE);
 
-	memcpy(skb->data - BNXT_RX_OFFSET, data, len + BNXT_RX_OFFSET);
+	memcpy(skb->data - NET_IP_ALIGN, data - NET_IP_ALIGN,
+	       len + NET_IP_ALIGN);
 
 	dma_sync_single_for_device(&pdev->dev, mapping,
 				   bp->rx_copy_thresh,
@@ -951,6 +954,7 @@ static void bnxt_tpa_start(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 	}
 
 	prod_rx_buf->data = tpa_info->data;
+	prod_rx_buf->data_ptr = tpa_info->data_ptr;
 
 	mapping = tpa_info->mapping;
 	dma_unmap_addr_set(prod_rx_buf, mapping, mapping);
@@ -960,6 +964,7 @@ static void bnxt_tpa_start(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 	prod_bd->rx_bd_haddr = cpu_to_le64(mapping);
 
 	tpa_info->data = cons_rx_buf->data;
+	tpa_info->data_ptr = cons_rx_buf->data_ptr;
 	cons_rx_buf->data = NULL;
 	tpa_info->mapping = dma_unmap_addr(cons_rx_buf, mapping);
 
@@ -1192,12 +1197,13 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 	struct bnxt_cp_ring_info *cpr = &bnapi->cp_ring;
 	struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
 	u8 agg_id = TPA_END_AGG_ID(tpa_end);
-	u8 *data, agg_bufs;
+	u8 *data_ptr, agg_bufs;
 	u16 cp_cons = RING_CMP(*raw_cons);
 	unsigned int len;
 	struct bnxt_tpa_info *tpa_info;
 	dma_addr_t mapping;
 	struct sk_buff *skb;
+	void *data;
 
 	if (unlikely(bnapi->in_reset)) {
 		int rc = bnxt_discard_rx(bp, bnapi, raw_cons, tpa_end);
@@ -1209,7 +1215,8 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 
 	tpa_info = &rxr->rx_tpa[agg_id];
 	data = tpa_info->data;
-	prefetch(data);
+	data_ptr = tpa_info->data_ptr;
+	prefetch(data_ptr);
 	len = tpa_info->len;
 	mapping = tpa_info->mapping;
 
@@ -1232,7 +1239,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 	}
 
 	if (len <= bp->rx_copy_thresh) {
-		skb = bnxt_copy_skb(bnapi, data, len, mapping);
+		skb = bnxt_copy_skb(bnapi, data_ptr, len, mapping);
 		if (!skb) {
 			bnxt_abort_tpa(bp, bnapi, cp_cons, agg_bufs);
 			return NULL;
@@ -1248,6 +1255,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		}
 
 		tpa_info->data = new_data;
+		tpa_info->data_ptr = new_data + BNXT_RX_OFFSET;
 		tpa_info->mapping = new_mapping;
 
 		skb = build_skb(data, 0);
@@ -1316,9 +1324,10 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 	u16 cons, prod, cp_cons = RING_CMP(tmp_raw_cons);
 	struct bnxt_sw_rx_bd *rx_buf;
 	unsigned int len;
-	u8 *data, agg_bufs, cmp_type;
+	u8 *data_ptr, agg_bufs, cmp_type;
 	dma_addr_t dma_addr;
 	struct sk_buff *skb;
+	void *data;
 	int rc = 0;
 
 	rxcmp = (struct rx_cmp *)
@@ -1363,13 +1372,14 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 	cons = rxcmp->rx_cmp_opaque;
 	rx_buf = &rxr->rx_buf_ring[cons];
 	data = rx_buf->data;
+	data_ptr = rx_buf->data_ptr;
 	if (unlikely(cons != rxr->rx_next_cons)) {
 		int rc1 = bnxt_discard_rx(bp, bnapi, raw_cons, rxcmp);
 
 		bnxt_sched_reset(bp, rxr);
 		return rc1;
 	}
-	prefetch(data);
+	prefetch(data_ptr);
 
 	agg_bufs = (le32_to_cpu(rxcmp->rx_cmp_misc_v1) & RX_CMP_AGG_BUFS) >>
 				RX_CMP_AGG_BUFS_SHIFT;
@@ -1396,14 +1406,14 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 	dma_addr = dma_unmap_addr(rx_buf, mapping);
 
 	if (len <= bp->rx_copy_thresh) {
-		skb = bnxt_copy_skb(bnapi, data, len, dma_addr);
+		skb = bnxt_copy_skb(bnapi, data_ptr, len, dma_addr);
 		bnxt_reuse_rx_data(rxr, cons, data);
 		if (!skb) {
 			rc = -ENOMEM;
 			goto next_rx;
 		}
 	} else {
-		skb = bnxt_rx_skb(bp, rxr, cons, prod, data, dma_addr, len);
+		skb = bp->rx_skb_func(bp, rxr, cons, prod, data, dma_addr, len);
 		if (!skb) {
 			rc = -ENOMEM;
 			goto next_rx;
@@ -1880,7 +1890,7 @@ static void bnxt_free_rx_skbs(struct bnxt *bp)
 
 		for (j = 0; j < max_idx; j++) {
 			struct bnxt_sw_rx_bd *rx_buf = &rxr->rx_buf_ring[j];
-			u8 *data = rx_buf->data;
+			void *data = rx_buf->data;
 
 			if (!data)
 				continue;
@@ -2326,6 +2336,7 @@ static int bnxt_init_one_rx_ring(struct bnxt *bp, int ring_nr)
 					return -ENOMEM;
 
 				rxr->rx_tpa[i].data = data;
+				rxr->rx_tpa[i].data_ptr = data + BNXT_RX_OFFSET;
 				rxr->rx_tpa[i].mapping = mapping;
 			}
 		} else {
@@ -2550,6 +2561,12 @@ void bnxt_set_ring_params(struct bnxt *bp)
 	bp->cp_ring_mask = bp->cp_bit - 1;
 }
 
+static int bnxt_set_rx_skb_mode(struct bnxt *bp)
+{
+	bp->rx_skb_func = bnxt_rx_skb;
+	return 0;
+}
+
 static void bnxt_free_vnic_attributes(struct bnxt *bp)
 {
 	int i;
@@ -7299,6 +7316,7 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	bnxt_hwrm_func_qcfg(bp);
 	bnxt_hwrm_port_led_qcaps(bp);
 
+	bnxt_set_rx_skb_mode(bp);
 	bnxt_set_tpa_flags(bp);
 	bnxt_set_ring_params(bp);
 	bnxt_set_max_func_irqs(bp, max_irqs);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 52a1cc0..33302b0 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -516,7 +516,8 @@ struct bnxt_sw_tx_bd {
 };
 
 struct bnxt_sw_rx_bd {
-	u8			*data;
+	void			*data;
+	u8			*data_ptr;
 	DEFINE_DMA_UNMAP_ADDR(mapping);
 };
 
@@ -576,7 +577,8 @@ struct bnxt_tx_ring_info {
 };
 
 struct bnxt_tpa_info {
-	u8			*data;
+	void			*data;
+	u8			*data_ptr;
 	dma_addr_t		mapping;
 	u16			len;
 	unsigned short		gso_type;
@@ -988,6 +990,11 @@ struct bnxt {
 	struct sk_buff *	(*gro_func)(struct bnxt_tpa_info *, int, int,
 					    struct sk_buff *);
 
+	struct sk_buff *	(*rx_skb_func)(struct bnxt *,
+					       struct bnxt_rx_ring_info *,
+					       u16, u16, void *, dma_addr_t,
+					       unsigned int);
+
 	u32			rx_buf_size;
 	u32			rx_buf_use_size;	/* useable size */
 	u32			rx_ring_size;
-- 
1.8.3.1

Re: [PATCH net-next 01/10] bnxt_en: Refactor rx SKB function.

[Jakub Kicinski]

On Mon, 30 Jan 2017 20:49:26 -0500, Michael Chan wrote:
> @@ -776,7 +778,7 @@ static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
>  	}
>  
>  	skb_reserve(skb, BNXT_RX_OFFSET);
> -	skb_put(skb, len);
> +	skb_put(skb, len & 0xffff);
>  	return skb;
>  }

Looks unrelated?

Re: [PATCH net-next 01/10] bnxt_en: Refactor rx SKB function.

[David Miller]

From: Michael Chan <michael.chan@broadcom.com>
Date: Mon, 30 Jan 2017 20:49:26 -0500

> @@ -776,7 +778,7 @@ static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
>  	}
>  
>  	skb_reserve(skb, BNXT_RX_OFFSET);
> -	skb_put(skb, len);
> +	skb_put(skb, len & 0xffff);
>  	return skb;
>  }
>  

Like Jakub I wonder about this.

The caller extracts the length field out of the descriptor using a
right shift of an unsigned value by 16 bits.  The mask seems
completely unnecessary.

If it is needed, perhaps due to some subsequent change, then please
document it and pair the change with the part the necessitates it.

Thank you.

[PATCH net-next 02/10] bnxt_en: Add bp->rx_dir field for rx buffer DMA direction.

[Michael Chan]

When driver is running in XDP mode, rx buffers are DMA mapped as
DMA_BIDIRECTIONAL.  Add a field so the code will map/unmap rx buffers
according to this field.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 22 ++++++++++------------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  1 +
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index d419199..c343ade 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -584,7 +584,7 @@ static inline u8 *__bnxt_alloc_rx_data(struct bnxt *bp, dma_addr_t *mapping,
 		return NULL;
 
 	*mapping = dma_map_single(&pdev->dev, data + BNXT_RX_DMA_OFFSET,
-				  bp->rx_buf_use_size, PCI_DMA_FROMDEVICE);
+				  bp->rx_buf_use_size, bp->rx_dir);
 
 	if (dma_mapping_error(&pdev->dev, *mapping)) {
 		kfree(data);
@@ -771,7 +771,7 @@ static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
 
 	skb = build_skb(data, 0);
 	dma_unmap_single(&bp->pdev->dev, dma_addr, bp->rx_buf_use_size,
-			 PCI_DMA_FROMDEVICE);
+			 bp->rx_dir);
 	if (!skb) {
 		kfree(data);
 		return NULL;
@@ -877,15 +877,14 @@ static inline struct sk_buff *bnxt_copy_skb(struct bnxt_napi *bnapi, u8 *data,
 	if (!skb)
 		return NULL;
 
-	dma_sync_single_for_cpu(&pdev->dev, mapping,
-				bp->rx_copy_thresh, PCI_DMA_FROMDEVICE);
+	dma_sync_single_for_cpu(&pdev->dev, mapping, bp->rx_copy_thresh,
+				bp->rx_dir);
 
 	memcpy(skb->data - NET_IP_ALIGN, data - NET_IP_ALIGN,
 	       len + NET_IP_ALIGN);
 
-	dma_sync_single_for_device(&pdev->dev, mapping,
-				   bp->rx_copy_thresh,
-				   PCI_DMA_FROMDEVICE);
+	dma_sync_single_for_device(&pdev->dev, mapping, bp->rx_copy_thresh,
+				   bp->rx_dir);
 
 	skb_put(skb, len);
 	return skb;
@@ -1260,7 +1259,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 
 		skb = build_skb(data, 0);
 		dma_unmap_single(&bp->pdev->dev, mapping, bp->rx_buf_use_size,
-				 PCI_DMA_FROMDEVICE);
+				 bp->rx_dir);
 
 		if (!skb) {
 			kfree(data);
@@ -1879,8 +1878,7 @@ static void bnxt_free_rx_skbs(struct bnxt *bp)
 				dma_unmap_single(
 					&pdev->dev,
 					dma_unmap_addr(tpa_info, mapping),
-					bp->rx_buf_use_size,
-					PCI_DMA_FROMDEVICE);
+					bp->rx_buf_use_size, bp->rx_dir);
 
 				tpa_info->data = NULL;
 
@@ -1897,8 +1895,7 @@ static void bnxt_free_rx_skbs(struct bnxt *bp)
 
 			dma_unmap_single(&pdev->dev,
 					 dma_unmap_addr(rx_buf, mapping),
-					 bp->rx_buf_use_size,
-					 PCI_DMA_FROMDEVICE);
+					 bp->rx_buf_use_size, bp->rx_dir);
 
 			rx_buf->data = NULL;
 
@@ -2563,6 +2560,7 @@ void bnxt_set_ring_params(struct bnxt *bp)
 
 static int bnxt_set_rx_skb_mode(struct bnxt *bp)
 {
+	bp->rx_dir = DMA_FROM_DEVICE;
 	bp->rx_skb_func = bnxt_rx_skb;
 	return 0;
 }
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 33302b0..b0da02d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -997,6 +997,7 @@ struct bnxt {
 
 	u32			rx_buf_size;
 	u32			rx_buf_use_size;	/* useable size */
+	enum dma_data_direction	rx_dir;
 	u32			rx_ring_size;
 	u32			rx_agg_ring_size;
 	u32			rx_copy_thresh;
-- 
1.8.3.1

[PATCH net-next 03/10] bnxt_en: Add RX page mode support.

[Michael Chan]

This mode is to support XDP.  In this mode, each rx ring is configured with
page sized buffers for linear placement of each packet.  MTU will be
restricted to what the page sized buffers can support.

Signed-off-by: Michael Chan <michael.chan@broadocm.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 121 ++++++++++++++++++++++++++----
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |   7 ++
 2 files changed, 115 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index c343ade..c63570d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -573,6 +573,24 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
 	}
 }
 
+static struct page *__bnxt_alloc_rx_page(struct bnxt *bp, dma_addr_t *mapping,
+					 gfp_t gfp)
+{
+	struct device *dev = &bp->pdev->dev;
+	struct page *page;
+
+	page = alloc_page(gfp);
+	if (!page)
+		return NULL;
+
+	*mapping = dma_map_page(dev, page, 0, PAGE_SIZE, bp->rx_dir);
+	if (dma_mapping_error(dev, *mapping)) {
+		__free_page(page);
+		return NULL;
+	}
+	return page;
+}
+
 static inline u8 *__bnxt_alloc_rx_data(struct bnxt *bp, dma_addr_t *mapping,
 				       gfp_t gfp)
 {
@@ -599,15 +617,25 @@ static inline int bnxt_alloc_rx_data(struct bnxt *bp,
 {
 	struct rx_bd *rxbd = &rxr->rx_desc_ring[RX_RING(prod)][RX_IDX(prod)];
 	struct bnxt_sw_rx_bd *rx_buf = &rxr->rx_buf_ring[prod];
-	u8 *data;
 	dma_addr_t mapping;
 
-	data = __bnxt_alloc_rx_data(bp, &mapping, gfp);
-	if (!data)
-		return -ENOMEM;
+	if (BNXT_RX_PAGE_MODE(bp)) {
+		struct page *page = __bnxt_alloc_rx_page(bp, &mapping, gfp);
 
-	rx_buf->data = data;
-	rx_buf->data_ptr = data + BNXT_RX_OFFSET;
+		if (!page)
+			return -ENOMEM;
+
+		rx_buf->data = page;
+		rx_buf->data_ptr = page_address(page) + NET_IP_ALIGN;
+	} else {
+		u8 *data = __bnxt_alloc_rx_data(bp, &mapping, gfp);
+
+		if (!data)
+			return -ENOMEM;
+
+		rx_buf->data = data;
+		rx_buf->data_ptr = data + BNXT_RX_OFFSET;
+	}
 	dma_unmap_addr_set(rx_buf, mapping, mapping);
 
 	rxbd->rx_bd_haddr = cpu_to_le64(mapping);
@@ -755,6 +783,51 @@ static void bnxt_reuse_rx_agg_bufs(struct bnxt_napi *bnapi, u16 cp_cons,
 	rxr->rx_sw_agg_prod = sw_prod;
 }
 
+static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp,
+					struct bnxt_rx_ring_info *rxr,
+					u16 cons, u16 prod,
+					void *data, dma_addr_t dma_addr,
+					unsigned int len)
+{
+	struct bnxt_sw_rx_bd *cons_rx_buf = &rxr->rx_buf_ring[cons];
+	unsigned int payload = len >> 16;
+	struct skb_frag_struct *frag;
+	struct page *page = data;
+	struct sk_buff *skb;
+	char *data_ptr;
+	int err;
+
+	len &= 0xffff;
+	err = bnxt_alloc_rx_data(bp, rxr, prod, GFP_ATOMIC);
+	if (unlikely(err)) {
+		bnxt_reuse_rx_data(rxr, cons, data);
+		return NULL;
+	}
+	dma_unmap_page(&bp->pdev->dev, dma_addr, PAGE_SIZE, bp->rx_dir);
+
+	data_ptr = cons_rx_buf->data_ptr;
+	if (unlikely(!payload))
+		payload = eth_get_headlen(data_ptr, len);
+
+	skb = napi_alloc_skb(&rxr->bnapi->napi, payload);
+	if (!skb) {
+		__free_page(page);
+		return NULL;
+	}
+
+	skb_add_rx_frag(skb, 0, page, NET_IP_ALIGN, len, PAGE_SIZE);
+	memcpy(skb->data - NET_IP_ALIGN, data_ptr - NET_IP_ALIGN,
+	       payload + NET_IP_ALIGN);
+
+	frag = &skb_shinfo(skb)->frags[0];
+	skb_frag_size_sub(frag, payload);
+	frag->page_offset += payload;
+	skb->data_len -= payload;
+	skb->tail += payload;
+
+	return skb;
+}
+
 static struct sk_buff *bnxt_rx_skb(struct bnxt *bp,
 				   struct bnxt_rx_ring_info *rxr, u16 cons,
 				   u16 prod, void *data, dma_addr_t dma_addr,
@@ -1412,7 +1485,12 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 			goto next_rx;
 		}
 	} else {
-		skb = bp->rx_skb_func(bp, rxr, cons, prod, data, dma_addr, len);
+		unsigned int payload_len;
+
+		payload_len = (le32_to_cpu(rxcmp->rx_cmp_misc_v1) &
+			       RX_CMP_PAYLOAD_OFFSET) | len;
+		skb = bp->rx_skb_func(bp, rxr, cons, prod, data, dma_addr,
+				      payload_len);
 		if (!skb) {
 			rc = -ENOMEM;
 			goto next_rx;
@@ -1899,7 +1977,10 @@ static void bnxt_free_rx_skbs(struct bnxt *bp)
 
 			rx_buf->data = NULL;
 
-			kfree(data);
+			if (BNXT_RX_PAGE_MODE(bp))
+				__free_page(data);
+			else
+				kfree(data);
 		}
 
 		for (j = 0; j < max_agg_idx; j++) {
@@ -2558,10 +2639,24 @@ void bnxt_set_ring_params(struct bnxt *bp)
 	bp->cp_ring_mask = bp->cp_bit - 1;
 }
 
-static int bnxt_set_rx_skb_mode(struct bnxt *bp)
+int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode)
 {
-	bp->rx_dir = DMA_FROM_DEVICE;
-	bp->rx_skb_func = bnxt_rx_skb;
+	if (page_mode) {
+		if (bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU)
+			return -EOPNOTSUPP;
+		bp->dev->max_mtu = BNXT_MAX_PAGE_MODE_MTU;
+		bp->flags &= ~BNXT_FLAG_AGG_RINGS;
+		bp->flags |= BNXT_FLAG_NO_AGG_RINGS | BNXT_FLAG_RX_PAGE_MODE;
+		bp->dev->hw_features &= ~NETIF_F_LRO;
+		bp->dev->features &= ~NETIF_F_LRO;
+		bp->rx_dir = DMA_BIDIRECTIONAL;
+		bp->rx_skb_func = bnxt_rx_page_skb;
+	} else {
+		bp->dev->max_mtu = BNXT_MAX_MTU;
+		bp->flags &= ~BNXT_FLAG_RX_PAGE_MODE;
+		bp->rx_dir = DMA_FROM_DEVICE;
+		bp->rx_skb_func = bnxt_rx_skb;
+	}
 	return 0;
 }
 
@@ -7273,7 +7368,7 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	/* MTU range: 60 - 9500 */
 	dev->min_mtu = ETH_ZLEN;
-	dev->max_mtu = 9500;
+	dev->max_mtu = BNXT_MAX_MTU;
 
 	bnxt_dcb_init(bp);
 
@@ -7314,7 +7409,7 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	bnxt_hwrm_func_qcfg(bp);
 	bnxt_hwrm_port_led_qcaps(bp);
 
-	bnxt_set_rx_skb_mode(bp);
+	bnxt_set_rx_skb_mode(bp, false);
 	bnxt_set_tpa_flags(bp);
 	bnxt_set_ring_params(bp);
 	bnxt_set_max_func_irqs(bp, max_irqs);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index b0da02d..b55a9c1 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -416,6 +416,10 @@ struct rx_tpa_end_cmp_ext {
 
 #define BNXT_RX_PAGE_SIZE (1 << BNXT_RX_PAGE_SHIFT)
 
+#define BNXT_MAX_MTU		9500
+#define BNXT_MAX_PAGE_MODE_MTU	\
+	((unsigned int)PAGE_SIZE - VLAN_ETH_HLEN - NET_IP_ALIGN)
+
 #define BNXT_MIN_PKT_SIZE	52
 
 #define BNXT_NUM_TESTS(bp)	0
@@ -967,6 +971,7 @@ struct bnxt {
 	#define BNXT_FLAG_ROCE_CAP	(BNXT_FLAG_ROCEV1_CAP |	\
 					 BNXT_FLAG_ROCEV2_CAP)
 	#define BNXT_FLAG_NO_AGG_RINGS	0x20000
+	#define BNXT_FLAG_RX_PAGE_MODE	0x40000
 	#define BNXT_FLAG_CHIP_NITRO_A0	0x1000000
 
 	#define BNXT_FLAG_ALL_CONFIG_FEATS (BNXT_FLAG_TPA |		\
@@ -978,6 +983,7 @@ struct bnxt {
 #define BNXT_NPAR(bp)		((bp)->port_partition_type)
 #define BNXT_SINGLE_PF(bp)	(BNXT_PF(bp) && !BNXT_NPAR(bp))
 #define BNXT_CHIP_TYPE_NITRO_A0(bp) ((bp)->flags & BNXT_FLAG_CHIP_NITRO_A0)
+#define BNXT_RX_PAGE_MODE(bp)	((bp)->flags & BNXT_FLAG_RX_PAGE_MODE)
 
 	struct bnxt_en_dev	*edev;
 	struct bnxt_en_dev *	(*ulp_probe)(struct net_device *);
@@ -1168,6 +1174,7 @@ struct bnxt {
 #define BNXT_MAX_PHY_I2C_RESP_SIZE		64
 
 void bnxt_set_ring_params(struct bnxt *);
+int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode);
 void bnxt_hwrm_cmd_hdr_init(struct bnxt *, void *, u16, u16, u16);
 int _hwrm_send_message(struct bnxt *, void *, u32, int);
 int hwrm_send_message(struct bnxt *, void *, u32, int);
-- 
1.8.3.1

[PATCH net-next 04/10] bnxt_en: Use event bit map in RX path.

[Michael Chan]

In the current code, we have separate rx_event and agg_event parameters
to keep track of rx and aggregation events.  Combine these events into
an u8 event mask with different bits defined for different events.  This
way, it is easier to expand the logic to include XDP tx events.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 28 +++++++++++++---------------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  3 +++
 2 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index c63570d..0f6ca67 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1264,7 +1264,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 					   u32 *raw_cons,
 					   struct rx_tpa_end_cmp *tpa_end,
 					   struct rx_tpa_end_cmp_ext *tpa_end1,
-					   bool *agg_event)
+					   u8 *event)
 {
 	struct bnxt_cp_ring_info *cpr = &bnapi->cp_ring;
 	struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
@@ -1299,7 +1299,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		if (!bnxt_agg_bufs_valid(bp, cpr, agg_bufs, raw_cons))
 			return ERR_PTR(-EBUSY);
 
-		*agg_event = true;
+		*event |= BNXT_AGG_EVENT;
 		cp_cons = NEXT_CMP(cp_cons);
 	}
 
@@ -1385,7 +1385,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
  * -EIO    - packet aborted due to hw error indicated in BD
  */
 static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
-		       bool *agg_event)
+		       u8 *event)
 {
 	struct bnxt_cp_ring_info *cpr = &bnapi->cp_ring;
 	struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
@@ -1426,8 +1426,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 	} else if (cmp_type == CMP_TYPE_RX_L2_TPA_END_CMP) {
 		skb = bnxt_tpa_end(bp, bnapi, &tmp_raw_cons,
 				   (struct rx_tpa_end_cmp *)rxcmp,
-				   (struct rx_tpa_end_cmp_ext *)rxcmp1,
-				   agg_event);
+				   (struct rx_tpa_end_cmp_ext *)rxcmp1, event);
 
 		if (unlikely(IS_ERR(skb)))
 			return -EBUSY;
@@ -1461,7 +1460,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 			return -EBUSY;
 
 		cp_cons = NEXT_CMP(cp_cons);
-		*agg_event = true;
+		*event |= BNXT_AGG_EVENT;
 	}
 
 	rx_buf->data = NULL;
@@ -1714,8 +1713,7 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 	u32 cons;
 	int tx_pkts = 0;
 	int rx_pkts = 0;
-	bool rx_event = false;
-	bool agg_event = false;
+	u8 event = 0;
 	struct tx_cmp *txcmp;
 
 	while (1) {
@@ -1737,12 +1735,12 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 			if (unlikely(tx_pkts > bp->tx_wake_thresh))
 				rx_pkts = budget;
 		} else if ((TX_CMP_TYPE(txcmp) & 0x30) == 0x10) {
-			rc = bnxt_rx_pkt(bp, bnapi, &raw_cons, &agg_event);
+			rc = bnxt_rx_pkt(bp, bnapi, &raw_cons, &event);
 			if (likely(rc >= 0))
 				rx_pkts += rc;
 			else if (rc == -EBUSY)	/* partial completion */
 				break;
-			rx_event = true;
+			event |= BNXT_RX_EVENT;
 		} else if (unlikely((TX_CMP_TYPE(txcmp) ==
 				     CMPL_BASE_TYPE_HWRM_DONE) ||
 				    (TX_CMP_TYPE(txcmp) ==
@@ -1767,12 +1765,12 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 	if (tx_pkts)
 		bnxt_tx_int(bp, bnapi, tx_pkts);
 
-	if (rx_event) {
+	if (event & BNXT_RX_EVENT) {
 		struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
 
 		writel(DB_KEY_RX | rxr->rx_prod, rxr->rx_doorbell);
 		writel(DB_KEY_RX | rxr->rx_prod, rxr->rx_doorbell);
-		if (agg_event) {
+		if (event & BNXT_AGG_EVENT) {
 			writel(DB_KEY_RX | rxr->rx_agg_prod,
 			       rxr->rx_agg_doorbell);
 			writel(DB_KEY_RX | rxr->rx_agg_prod,
@@ -1793,7 +1791,7 @@ static int bnxt_poll_nitroa0(struct napi_struct *napi, int budget)
 	u32 cp_cons, tmp_raw_cons;
 	u32 raw_cons = cpr->cp_raw_cons;
 	u32 rx_pkts = 0;
-	bool agg_event = false;
+	u8 event = 0;
 
 	while (1) {
 		int rc;
@@ -1817,7 +1815,7 @@ static int bnxt_poll_nitroa0(struct napi_struct *napi, int budget)
 			rxcmp1->rx_cmp_cfa_code_errors_v2 |=
 				cpu_to_le32(RX_CMPL_ERRORS_CRC_ERROR);
 
-			rc = bnxt_rx_pkt(bp, bnapi, &raw_cons, &agg_event);
+			rc = bnxt_rx_pkt(bp, bnapi, &raw_cons, &event);
 			if (likely(rc == -EIO))
 				rx_pkts++;
 			else if (rc == -EBUSY)	/* partial completion */
@@ -1840,7 +1838,7 @@ static int bnxt_poll_nitroa0(struct napi_struct *napi, int budget)
 	writel(DB_KEY_RX | rxr->rx_prod, rxr->rx_doorbell);
 	writel(DB_KEY_RX | rxr->rx_prod, rxr->rx_doorbell);
 
-	if (agg_event) {
+	if (event & BNXT_AGG_EVENT) {
 		writel(DB_KEY_RX | rxr->rx_agg_prod, rxr->rx_agg_doorbell);
 		writel(DB_KEY_RX | rxr->rx_agg_prod, rxr->rx_agg_doorbell);
 	}
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index b55a9c1..2202113 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -511,6 +511,9 @@ struct rx_tpa_end_cmp_ext {
 #define BNXT_HWRM_REQS_PER_PAGE		(BNXT_PAGE_SIZE /	\
 					 BNXT_HWRM_REQ_MAX_SIZE)
 
+#define BNXT_RX_EVENT	1
+#define BNXT_AGG_EVENT	2
+
 struct bnxt_sw_tx_bd {
 	struct sk_buff		*skb;
 	DEFINE_DMA_UNMAP_ADDR(mapping);
-- 
1.8.3.1

[PATCH net-next 05/10] bnxt_en: Centralize logic to reserve rings.

[Michael Chan]

Currently, bnxt_setup_tc() and bnxt_set_channels() have similar and
duplicated code to check and reserve rx and tx rings.  Add a new
function bnxt_reserve_rings() to centralize the logic.  This will
make it easier to add XDP_TX support which requires allocating a
new set of TX rings.

Also, the tx ring checking logic in bnxt_setup_msix() can be removed.
The rings have been reserved before hand.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c         | 68 ++++++++++++++---------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h         |  2 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 39 +++----------
 3 files changed, 52 insertions(+), 57 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 0f6ca67..cb30ba4 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4204,7 +4204,7 @@ int __bnxt_hwrm_get_tx_rings(struct bnxt *bp, u16 fid, int *tx_rings)
 	return rc;
 }
 
-int bnxt_hwrm_reserve_tx_rings(struct bnxt *bp, int *tx_rings)
+static int bnxt_hwrm_reserve_tx_rings(struct bnxt *bp, int *tx_rings)
 {
 	struct hwrm_func_cfg_input req = {0};
 	int rc;
@@ -4997,19 +4997,12 @@ static void bnxt_setup_msix(struct bnxt *bp)
 
 	tcs = netdev_get_num_tc(dev);
 	if (tcs > 1) {
-		bp->tx_nr_rings_per_tc = bp->tx_nr_rings / tcs;
-		if (bp->tx_nr_rings_per_tc == 0) {
-			netdev_reset_tc(dev);
-			bp->tx_nr_rings_per_tc = bp->tx_nr_rings;
-		} else {
-			int i, off, count;
+		int i, off, count;
 
-			bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tcs;
-			for (i = 0; i < tcs; i++) {
-				count = bp->tx_nr_rings_per_tc;
-				off = i * count;
-				netdev_set_tc_queue(dev, i, count, off);
-			}
+		for (i = 0; i < tcs; i++) {
+			count = bp->tx_nr_rings_per_tc;
+			off = i * count;
+			netdev_set_tc_queue(dev, i, count, off);
 		}
 	}
 
@@ -6571,6 +6564,37 @@ static void bnxt_sp_task(struct work_struct *work)
 	clear_bit(BNXT_STATE_IN_SP_TASK, &bp->state);
 }
 
+/* Under rtnl_lock */
+int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs)
+{
+	int max_rx, max_tx, tx_sets = 1;
+	int tx_rings_needed;
+	bool sh = true;
+	int rc;
+
+	if (!(bp->flags & BNXT_FLAG_SHARED_RINGS))
+		sh = false;
+
+	if (tcs)
+		tx_sets = tcs;
+
+	rc = bnxt_get_max_rings(bp, &max_rx, &max_tx, sh);
+	if (rc)
+		return rc;
+
+	if (max_rx < rx)
+		return -ENOMEM;
+
+	tx_rings_needed = tx * tx_sets;
+	if (max_tx < tx_rings_needed)
+		return -ENOMEM;
+
+	if (bnxt_hwrm_reserve_tx_rings(bp, &tx_rings_needed) ||
+	    tx_rings_needed < (tx * tx_sets))
+		return -ENOMEM;
+	return 0;
+}
+
 static int bnxt_init_board(struct pci_dev *pdev, struct net_device *dev)
 {
 	int rc;
@@ -6733,6 +6757,7 @@ int bnxt_setup_mq_tc(struct net_device *dev, u8 tc)
 {
 	struct bnxt *bp = netdev_priv(dev);
 	bool sh = false;
+	int rc;
 
 	if (tc > bp->max_tc) {
 		netdev_err(dev, "too many traffic classes requested: %d Max supported is %d\n",
@@ -6746,19 +6771,10 @@ int bnxt_setup_mq_tc(struct net_device *dev, u8 tc)
 	if (bp->flags & BNXT_FLAG_SHARED_RINGS)
 		sh = true;
 
-	if (tc) {
-		int max_rx_rings, max_tx_rings, req_tx_rings, rsv_tx_rings, rc;
-
-		req_tx_rings = bp->tx_nr_rings_per_tc * tc;
-		rc = bnxt_get_max_rings(bp, &max_rx_rings, &max_tx_rings, sh);
-		if (rc || req_tx_rings > max_tx_rings)
-			return -ENOMEM;
-
-		rsv_tx_rings = req_tx_rings;
-		if (bnxt_hwrm_reserve_tx_rings(bp, &rsv_tx_rings) ||
-		    rsv_tx_rings < req_tx_rings)
-			return -ENOMEM;
-	}
+	rc = bnxt_reserve_rings(bp, bp->tx_nr_rings_per_tc,
+				bp->rx_nr_rings, tc);
+	if (rc)
+		return rc;
 
 	/* Needs to close the device and do hw resource re-allocations */
 	if (netif_running(bp->dev))
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 2202113..44dcc26 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1186,7 +1186,6 @@ int bnxt_hwrm_func_rgtr_async_events(struct bnxt *bp, unsigned long *bmap,
 				     int bmap_size);
 int bnxt_hwrm_vnic_cfg(struct bnxt *bp, u16 vnic_id);
 int __bnxt_hwrm_get_tx_rings(struct bnxt *bp, u16 fid, int *tx_rings);
-int bnxt_hwrm_reserve_tx_rings(struct bnxt *bp, int *tx_rings);
 int bnxt_hwrm_set_coal(struct bnxt *);
 unsigned int bnxt_get_max_func_stat_ctxs(struct bnxt *bp);
 void bnxt_set_max_func_stat_ctxs(struct bnxt *bp, unsigned int max);
@@ -1200,6 +1199,7 @@ int bnxt_hwrm_func_rgtr_async_events(struct bnxt *bp, unsigned long *bmap,
 int bnxt_hwrm_fw_set_time(struct bnxt *);
 int bnxt_open_nic(struct bnxt *, bool, bool);
 int bnxt_close_nic(struct bnxt *, bool, bool);
+int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs);
 int bnxt_setup_mq_tc(struct net_device *dev, u8 tc);
 int bnxt_get_max_rings(struct bnxt *, int *, int *, bool);
 void bnxt_restore_pf_fw_resources(struct bnxt *bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 24818e1..6f2568d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -387,10 +387,9 @@ static int bnxt_set_channels(struct net_device *dev,
 			     struct ethtool_channels *channel)
 {
 	struct bnxt *bp = netdev_priv(dev);
-	int max_rx_rings, max_tx_rings, tcs;
-	int req_tx_rings, rsv_tx_rings;
-	u32 rc = 0;
+	int req_tx_rings, req_rx_rings, tcs;
 	bool sh = false;
+	int rc = 0;
 
 	if (channel->other_count)
 		return -EINVAL;
@@ -410,32 +409,14 @@ static int bnxt_set_channels(struct net_device *dev,
 	if (channel->combined_count)
 		sh = true;
 
-	bnxt_get_max_rings(bp, &max_rx_rings, &max_tx_rings, sh);
-
 	tcs = netdev_get_num_tc(dev);
-	if (tcs > 1)
-		max_tx_rings /= tcs;
-
-	if (sh &&
-	    channel->combined_count > max_t(int, max_rx_rings, max_tx_rings))
-		return -ENOMEM;
-
-	if (!sh && (channel->rx_count > max_rx_rings ||
-		    channel->tx_count > max_tx_rings))
-		return -ENOMEM;
 
 	req_tx_rings = sh ? channel->combined_count : channel->tx_count;
-	req_tx_rings = min_t(int, req_tx_rings, max_tx_rings);
-	if (tcs > 1)
-		req_tx_rings *= tcs;
-
-	rsv_tx_rings = req_tx_rings;
-	if (bnxt_hwrm_reserve_tx_rings(bp, &rsv_tx_rings))
-		return -ENOMEM;
-
-	if (rsv_tx_rings < req_tx_rings) {
-		netdev_warn(dev, "Unable to allocate the requested tx rings\n");
-		return -ENOMEM;
+	req_rx_rings = sh ? channel->combined_count : channel->rx_count;
+	rc = bnxt_reserve_rings(bp, req_tx_rings, req_rx_rings, tcs);
+	if (rc) {
+		netdev_warn(dev, "Unable to allocate the requested rings\n");
+		return rc;
 	}
 
 	if (netif_running(dev)) {
@@ -454,10 +435,8 @@ static int bnxt_set_channels(struct net_device *dev,
 
 	if (sh) {
 		bp->flags |= BNXT_FLAG_SHARED_RINGS;
-		bp->rx_nr_rings = min_t(int, channel->combined_count,
-					max_rx_rings);
-		bp->tx_nr_rings_per_tc = min_t(int, channel->combined_count,
-					       max_tx_rings);
+		bp->rx_nr_rings = channel->combined_count;
+		bp->tx_nr_rings_per_tc = channel->combined_count;
 	} else {
 		bp->flags &= ~BNXT_FLAG_SHARED_RINGS;
 		bp->rx_nr_rings = channel->rx_count;
-- 
1.8.3.1

[PATCH net-next 06/10] bnxt_en: Add tx ring mapping logic.

[Michael Chan]

To support XDP_TX, we need to add a set of dedicated TX rings, each
associated with the NAPI of an RX ring.  To assign XDP rings and regular
rings in a flexible way, we add a bp->tx_ring_map[] array to do the
remapping.  In this patch, before we introduce XDP_TX, the mapping is 1:1.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 11 ++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  1 +
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index cb30ba4..db78103 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -262,8 +262,8 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		return NETDEV_TX_OK;
 	}
 
-	txr = &bp->tx_ring[i];
 	txq = netdev_get_tx_queue(dev, i);
+	txr = &bp->tx_ring[bp->tx_ring_map[i]];
 	prod = txr->tx_prod;
 
 	free_size = bnxt_tx_avail(bp, txr);
@@ -2967,6 +2967,8 @@ static void bnxt_free_mem(struct bnxt *bp, bool irq_re_init)
 		bnxt_free_stats(bp);
 		bnxt_free_ring_grps(bp);
 		bnxt_free_vnics(bp);
+		kfree(bp->tx_ring_map);
+		bp->tx_ring_map = NULL;
 		kfree(bp->tx_ring);
 		bp->tx_ring = NULL;
 		kfree(bp->rx_ring);
@@ -3019,6 +3021,12 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 		if (!bp->tx_ring)
 			return -ENOMEM;
 
+		bp->tx_ring_map = kcalloc(bp->tx_nr_rings, sizeof(u16),
+					  GFP_KERNEL);
+
+		if (!bp->tx_ring_map)
+			return -ENOMEM;
+
 		if (bp->flags & BNXT_FLAG_SHARED_RINGS)
 			j = 0;
 		else
@@ -3027,6 +3035,7 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 		for (i = 0; i < bp->tx_nr_rings; i++, j++) {
 			bp->tx_ring[i].bnapi = bp->bnapi[j];
 			bp->bnapi[j]->tx_ring = &bp->tx_ring[i];
+			bp->tx_ring_map[i] = i;
 		}
 
 		rc = bnxt_alloc_stats(bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 44dcc26..924c1fa 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -995,6 +995,7 @@ struct bnxt {
 
 	struct bnxt_rx_ring_info	*rx_ring;
 	struct bnxt_tx_ring_info	*tx_ring;
+	u16			*tx_ring_map;
 
 	struct sk_buff *	(*gro_func)(struct bnxt_tpa_info *, int, int,
 					    struct sk_buff *);
-- 
1.8.3.1

[PATCH net-next 07/10] bnxt_en: Add a set of TX rings to support XDP.

[Michael Chan]

Add logic for an extra set of TX rings for XDP.  If enabled, this
set of TX rings equals the number of RX rings and shares the same
IRQ as the RX ring set.  A new field bp->tx_nr_rings_xdp is added
to keep track of these TX XDP rings.  Adjust all other relevant functions
to handle bp->tx_nr_rings_xdp.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c         | 17 ++++++++++-------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h         |  3 ++-
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 16 ++++++++++++----
 3 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index db78103..295c91f 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -2219,6 +2219,8 @@ static int bnxt_alloc_tx_rings(struct bnxt *bp)
 			memset(txr->tx_push, 0, sizeof(struct tx_push_bd));
 		}
 		ring->queue_id = bp->q_info[j].queue_id;
+		if (i < bp->tx_nr_rings_xdp)
+			continue;
 		if (i % bp->tx_nr_rings_per_tc == (bp->tx_nr_rings_per_tc - 1))
 			j++;
 	}
@@ -3035,7 +3037,7 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 		for (i = 0; i < bp->tx_nr_rings; i++, j++) {
 			bp->tx_ring[i].bnapi = bp->bnapi[j];
 			bp->bnapi[j]->tx_ring = &bp->tx_ring[i];
-			bp->tx_ring_map[i] = i;
+			bp->tx_ring_map[i] = bp->tx_nr_rings_xdp + i;
 		}
 
 		rc = bnxt_alloc_stats(bp);
@@ -4958,7 +4960,8 @@ static int bnxt_set_real_num_queues(struct bnxt *bp)
 	int rc;
 	struct net_device *dev = bp->dev;
 
-	rc = netif_set_real_num_tx_queues(dev, bp->tx_nr_rings);
+	rc = netif_set_real_num_tx_queues(dev, bp->tx_nr_rings -
+					  bp->tx_nr_rings_xdp);
 	if (rc)
 		return rc;
 
@@ -6574,7 +6577,7 @@ static void bnxt_sp_task(struct work_struct *work)
 }
 
 /* Under rtnl_lock */
-int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs)
+int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs, int tx_xdp)
 {
 	int max_rx, max_tx, tx_sets = 1;
 	int tx_rings_needed;
@@ -6594,12 +6597,12 @@ int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs)
 	if (max_rx < rx)
 		return -ENOMEM;
 
-	tx_rings_needed = tx * tx_sets;
+	tx_rings_needed = tx * tx_sets + tx_xdp;
 	if (max_tx < tx_rings_needed)
 		return -ENOMEM;
 
 	if (bnxt_hwrm_reserve_tx_rings(bp, &tx_rings_needed) ||
-	    tx_rings_needed < (tx * tx_sets))
+	    tx_rings_needed < (tx * tx_sets + tx_xdp))
 		return -ENOMEM;
 	return 0;
 }
@@ -6780,8 +6783,8 @@ int bnxt_setup_mq_tc(struct net_device *dev, u8 tc)
 	if (bp->flags & BNXT_FLAG_SHARED_RINGS)
 		sh = true;
 
-	rc = bnxt_reserve_rings(bp, bp->tx_nr_rings_per_tc,
-				bp->rx_nr_rings, tc);
+	rc = bnxt_reserve_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings,
+				tc, bp->tx_nr_rings_xdp);
 	if (rc)
 		return rc;
 
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 924c1fa..9bd1a26 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1023,6 +1023,7 @@ struct bnxt {
 	int			tx_nr_pages;
 	int			tx_nr_rings;
 	int			tx_nr_rings_per_tc;
+	int			tx_nr_rings_xdp;
 
 	int			tx_wake_thresh;
 	int			tx_push_thresh;
@@ -1200,7 +1201,7 @@ int bnxt_hwrm_func_rgtr_async_events(struct bnxt *bp, unsigned long *bmap,
 int bnxt_hwrm_fw_set_time(struct bnxt *);
 int bnxt_open_nic(struct bnxt *, bool, bool);
 int bnxt_close_nic(struct bnxt *, bool, bool);
-int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs);
+int bnxt_reserve_rings(struct bnxt *bp, int tx, int rx, int tcs, int tx_xdp);
 int bnxt_setup_mq_tc(struct net_device *dev, u8 tc);
 int bnxt_get_max_rings(struct bnxt *, int *, int *, bool);
 void bnxt_restore_pf_fw_resources(struct bnxt *bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 6f2568d..7aa248d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -389,6 +389,7 @@ static int bnxt_set_channels(struct net_device *dev,
 	struct bnxt *bp = netdev_priv(dev);
 	int req_tx_rings, req_rx_rings, tcs;
 	bool sh = false;
+	int tx_xdp = 0;
 	int rc = 0;
 
 	if (channel->other_count)
@@ -413,7 +414,14 @@ static int bnxt_set_channels(struct net_device *dev,
 
 	req_tx_rings = sh ? channel->combined_count : channel->tx_count;
 	req_rx_rings = sh ? channel->combined_count : channel->rx_count;
-	rc = bnxt_reserve_rings(bp, req_tx_rings, req_rx_rings, tcs);
+	if (bp->tx_nr_rings_xdp) {
+		if (!sh) {
+			netdev_err(dev, "Only combined mode supported when XDP is enabled.\n");
+			return -EINVAL;
+		}
+		tx_xdp = req_rx_rings;
+	}
+	rc = bnxt_reserve_rings(bp, req_tx_rings, req_rx_rings, tcs, tx_xdp);
 	if (rc) {
 		netdev_warn(dev, "Unable to allocate the requested rings\n");
 		return rc;
@@ -442,10 +450,10 @@ static int bnxt_set_channels(struct net_device *dev,
 		bp->rx_nr_rings = channel->rx_count;
 		bp->tx_nr_rings_per_tc = channel->tx_count;
 	}
-
-	bp->tx_nr_rings = bp->tx_nr_rings_per_tc;
+	bp->tx_nr_rings_xdp = tx_xdp;
+	bp->tx_nr_rings = bp->tx_nr_rings_per_tc + tx_xdp;
 	if (tcs > 1)
-		bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tcs;
+		bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tcs + tx_xdp;
 
 	bp->cp_nr_rings = sh ? max_t(int, bp->tx_nr_rings, bp->rx_nr_rings) :
 			       bp->tx_nr_rings + bp->rx_nr_rings;
-- 
1.8.3.1

[PATCH net-next 08/10] bnxt_en: Refactor tx completion path.

[Michael Chan]

XDP_TX requires a different function to handle completion.  Add a
function pointer to handle tx completion logic.  Regular TX rings
will be assigned the current bnxt_tx_int() for the ->tx_int()
function pointer.

Also, add a struct page pointer as a union with the current skb pointer
to the struct bnxt_sw_tx_bd.  XDP TX rings will use the struct page
pointer.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c |  5 ++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h | 10 +++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 295c91f..d9098ee 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1763,7 +1763,7 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 	BNXT_CP_DB(cpr->cp_doorbell, cpr->cp_raw_cons);
 
 	if (tx_pkts)
-		bnxt_tx_int(bp, bnapi, tx_pkts);
+		bnapi->tx_int(bp, bnapi, tx_pkts);
 
 	if (event & BNXT_RX_EVENT) {
 		struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
@@ -3038,6 +3038,9 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 			bp->tx_ring[i].bnapi = bp->bnapi[j];
 			bp->bnapi[j]->tx_ring = &bp->tx_ring[i];
 			bp->tx_ring_map[i] = bp->tx_nr_rings_xdp + i;
+			if (i < bp->tx_nr_rings_xdp)
+				bp->bnapi[j]->flags |= BNXT_NAPI_FLAG_XDP;
+			bp->bnapi[j]->tx_int = bnxt_tx_int;
 		}
 
 		rc = bnxt_alloc_stats(bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 9bd1a26..f5d5971 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -515,7 +515,10 @@ struct rx_tpa_end_cmp_ext {
 #define BNXT_AGG_EVENT	2
 
 struct bnxt_sw_tx_bd {
-	struct sk_buff		*skb;
+	union {
+		struct sk_buff		*skb;
+		struct page		*page;
+	};
 	DEFINE_DMA_UNMAP_ADDR(mapping);
 	u8			is_gso;
 	u8			is_push;
@@ -663,6 +666,11 @@ struct bnxt_napi {
 	struct bnxt_rx_ring_info	*rx_ring;
 	struct bnxt_tx_ring_info	*tx_ring;
 
+	void			(*tx_int)(struct bnxt *, struct bnxt_napi *,
+					  int);
+	u32			flags;
+#define BNXT_NAPI_FLAG_XDP	0x1
+
 	bool			in_reset;
 };
 
-- 
1.8.3.1

[PATCH net-next 09/10] bnxt_en: Add basic XDP support.

[Michael Chan]

Add basic ndo_xdp support to setup and query program, configure the NIC
to run in rx page mode, and support XDP_PASS, XDP_DROP, XDP_ABORTED
actions only.  Use Kconfig option to enable XDP support.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Tested-by: Andy Gospodarek <gospo@broadcom.com>
---
 drivers/net/ethernet/broadcom/Kconfig         |   8 ++
 drivers/net/ethernet/broadcom/bnxt/Makefile   |   2 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  29 +++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |   6 ++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 141 ++++++++++++++++++++++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |  28 +++++
 6 files changed, 210 insertions(+), 4 deletions(-)
 create mode 100644 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
 create mode 100644 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h

diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig
index 940fb24..ca543a4 100644
--- a/drivers/net/ethernet/broadcom/Kconfig
+++ b/drivers/net/ethernet/broadcom/Kconfig
@@ -213,4 +213,12 @@ config BNXT_DCB
 
 	  If unsure, say N.
 
+config BNXT_XDP
+	bool "Xpress Data Path (XDP) driver support"
+	default n
+	depends on BNXT && BPF
+	---help---
+	  Say Y here if you want to enable XDP in the driver to support
+	  eBPF programs in the fast path.
+
 endif # NET_VENDOR_BROADCOM
diff --git a/drivers/net/ethernet/broadcom/bnxt/Makefile b/drivers/net/ethernet/broadcom/bnxt/Makefile
index 6082ed1..a7ca45b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/Makefile
+++ b/drivers/net/ethernet/broadcom/bnxt/Makefile
@@ -1,3 +1,3 @@
 obj-$(CONFIG_BNXT) += bnxt_en.o
 
-bnxt_en-y := bnxt.o bnxt_sriov.o bnxt_ethtool.o bnxt_dcb.o bnxt_ulp.o
+bnxt_en-y := bnxt.o bnxt_sriov.o bnxt_ethtool.o bnxt_dcb.o bnxt_ulp.o bnxt_xdp.o
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index d9098ee..ae1f400 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -33,6 +33,7 @@
 #include <linux/if.h>
 #include <linux/if_vlan.h>
 #include <linux/rtc.h>
+#include <linux/bpf.h>
 #include <net/ip.h>
 #include <net/tcp.h>
 #include <net/udp.h>
@@ -53,6 +54,7 @@
 #include "bnxt_sriov.h"
 #include "bnxt_ethtool.h"
 #include "bnxt_dcb.h"
+#include "bnxt_xdp.h"
 
 #define BNXT_TX_TIMEOUT		(5 * HZ)
 
@@ -643,8 +645,7 @@ static inline int bnxt_alloc_rx_data(struct bnxt *bp,
 	return 0;
 }
 
-static void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons,
-			       void *data)
+void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons, void *data)
 {
 	u16 prod = rxr->rx_prod;
 	struct bnxt_sw_rx_bd *cons_rx_buf, *prod_rx_buf;
@@ -1476,6 +1477,11 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
 	len = le32_to_cpu(rxcmp->rx_cmp_len_flags_type) >> RX_CMP_LEN_SHIFT;
 	dma_addr = dma_unmap_addr(rx_buf, mapping);
 
+	if (bnxt_rx_xdp(rxr, cons, data, data_ptr, len, dma_addr, event)) {
+		rc = 1;
+		goto next_rx;
+	}
+
 	if (len <= bp->rx_copy_thresh) {
 		skb = bnxt_copy_skb(bnapi, data_ptr, len, dma_addr);
 		bnxt_reuse_rx_data(rxr, cons, data);
@@ -2081,6 +2087,9 @@ static void bnxt_free_rx_rings(struct bnxt *bp)
 		struct bnxt_rx_ring_info *rxr = &bp->rx_ring[i];
 		struct bnxt_ring_struct *ring;
 
+		if (rxr->xdp_prog)
+			bpf_prog_put(rxr->xdp_prog);
+
 		kfree(rxr->rx_tpa);
 		rxr->rx_tpa = NULL;
 
@@ -2368,6 +2377,15 @@ static int bnxt_init_one_rx_ring(struct bnxt *bp, int ring_nr)
 	ring = &rxr->rx_ring_struct;
 	bnxt_init_rxbd_pages(ring, type);
 
+	if (BNXT_RX_PAGE_MODE(bp) && bp->xdp_prog) {
+		rxr->xdp_prog = bpf_prog_add(bp->xdp_prog, 1);
+		if (IS_ERR(rxr->xdp_prog)) {
+			int rc = PTR_ERR(rxr->xdp_prog);
+
+			rxr->xdp_prog = NULL;
+			return rc;
+		}
+	}
 	prod = rxr->rx_prod;
 	for (i = 0; i < bp->rx_ring_size; i++) {
 		if (bnxt_alloc_rx_data(bp, rxr, prod, GFP_KERNEL) != 0) {
@@ -2553,7 +2571,7 @@ static int bnxt_calc_nr_ring_pages(u32 ring_size, int desc_per_pg)
 	return pages;
 }
 
-static void bnxt_set_tpa_flags(struct bnxt *bp)
+void bnxt_set_tpa_flags(struct bnxt *bp)
 {
 	bp->flags &= ~BNXT_FLAG_TPA;
 	if (bp->flags & BNXT_FLAG_NO_AGG_RINGS)
@@ -7097,6 +7115,9 @@ static void bnxt_udp_tunnel_del(struct net_device *dev,
 #endif
 	.ndo_udp_tunnel_add	= bnxt_udp_tunnel_add,
 	.ndo_udp_tunnel_del	= bnxt_udp_tunnel_del,
+#ifdef CONFIG_BNXT_XDP
+	.ndo_xdp		= bnxt_xdp,
+#endif
 };
 
 static void bnxt_remove_one(struct pci_dev *pdev)
@@ -7121,6 +7142,8 @@ static void bnxt_remove_one(struct pci_dev *pdev)
 	pci_iounmap(pdev, bp->bar0);
 	kfree(bp->edev);
 	bp->edev = NULL;
+	if (bp->xdp_prog)
+		bpf_prog_put(bp->xdp_prog);
 	free_netdev(dev);
 
 	pci_release_regions(pdev);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index f5d5971..007e779 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -620,6 +620,8 @@ struct bnxt_rx_ring_info {
 	void __iomem		*rx_doorbell;
 	void __iomem		*rx_agg_doorbell;
 
+	struct bpf_prog		*xdp_prog;
+
 	struct rx_bd		*rx_desc_ring[MAX_RX_PAGES];
 	struct bnxt_sw_rx_bd	*rx_buf_ring;
 
@@ -1167,6 +1169,8 @@ struct bnxt {
 
 	u8			num_leds;
 	struct bnxt_led_info	leds[BNXT_MAX_LED];
+
+	struct bpf_prog		*xdp_prog;
 };
 
 #define BNXT_RX_STATS_OFFSET(counter)			\
@@ -1186,6 +1190,8 @@ struct bnxt {
 #define SFF_MODULE_ID_QSFP28			0x11
 #define BNXT_MAX_PHY_I2C_RESP_SIZE		64
 
+void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons, void *data);
+void bnxt_set_tpa_flags(struct bnxt *bp);
 void bnxt_set_ring_params(struct bnxt *);
 int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode);
 void bnxt_hwrm_cmd_hdr_init(struct bnxt *, void *, u16, u16, u16);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
new file mode 100644
index 0000000..133e515
--- /dev/null
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -0,0 +1,141 @@
+/* Broadcom NetXtreme-C/E network driver.
+ *
+ * Copyright (c) 2016-2017 Broadcom Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include "bnxt_hsi.h"
+#include "bnxt.h"
+#include "bnxt_xdp.h"
+
+#ifdef CONFIG_BNXT_XDP
+/* returns the following:
+ * true    - packet consumed by XDP and new buffer is allocated.
+ * false   - packet should be passed to the stack.
+ */
+bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons, void *data,
+		 u8 *data_ptr, unsigned int len, dma_addr_t dma_addr,
+		 u8 *event)
+{
+	struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog);
+	struct xdp_buff xdp;
+	u32 act;
+
+	if (!xdp_prog)
+		return false;
+
+	xdp.data = data_ptr;
+	xdp.data_end = xdp.data + len;
+	rcu_read_lock();
+	act = bpf_prog_run_xdp(xdp_prog, &xdp);
+	rcu_read_unlock();
+
+	switch (act) {
+	case XDP_PASS:
+		return false;
+
+	default:
+		bpf_warn_invalid_xdp_action(act);
+		/* Fall thru */
+	case XDP_DROP:
+	case XDP_ABORTED:
+		bnxt_reuse_rx_data(rxr, cons, data);
+		break;
+	}
+	return true;
+}
+
+/* Under rtnl_lock */
+static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog)
+{
+	struct net_device *dev = bp->dev;
+	int tx_xdp = 0, rc, tc;
+	struct bpf_prog *old;
+
+	if (prog && prog->xdp_adjust_head) {
+		netdev_err(dev, "Does not support bpf_xdp_adjust_head().\n");
+		return -EOPNOTSUPP;
+	}
+	if (prog && bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) {
+		netdev_err(dev, "MTU %d larger than largest XDP supported MTU %d.\n",
+			   bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU);
+		return -EOPNOTSUPP;
+	}
+	if (!(bp->flags & BNXT_FLAG_SHARED_RINGS)) {
+		netdev_err(dev, "ethtool rx/tx channels must be combined to support XDP.\n");
+		return -EOPNOTSUPP;
+	}
+	if (prog)
+		tx_xdp = bp->rx_nr_rings;
+
+	tc = netdev_get_num_tc(dev);
+	if (!tc)
+		tc = 1;
+	rc = bnxt_reserve_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings,
+				tc, tx_xdp);
+	if (rc) {
+		netdev_err(dev, "Unable to reserve enough TX rings to support XDP.\n");
+		return rc;
+	}
+	if (netif_running(dev))
+		bnxt_close_nic(bp, true, false);
+
+	old = xchg(&bp->xdp_prog, prog);
+	if (old)
+		bpf_prog_put(old);
+
+	if (prog) {
+		bnxt_set_rx_skb_mode(bp, true);
+	} else {
+		bool sh = (bp->flags & BNXT_FLAG_SHARED_RINGS) ? true : false;
+		int rx, tx;
+
+		bnxt_set_rx_skb_mode(bp, false);
+		bnxt_get_max_rings(bp, &rx, &tx, sh);
+		if (rx > 1) {
+			bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS;
+			bp->dev->hw_features |= NETIF_F_LRO;
+		}
+	}
+	bp->tx_nr_rings_xdp = tx_xdp;
+	bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp;
+	bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings);
+	bp->num_stat_ctxs = bp->cp_nr_rings;
+	bnxt_set_tpa_flags(bp);
+	bnxt_set_ring_params(bp);
+
+	if (netif_running(dev))
+		return bnxt_open_nic(bp, true, false);
+
+	return 0;
+}
+
+int bnxt_xdp(struct net_device *dev, struct netdev_xdp *xdp)
+{
+	struct bnxt *bp = netdev_priv(dev);
+	int rc;
+
+	switch (xdp->command) {
+	case XDP_SETUP_PROG:
+		rc = bnxt_xdp_set(bp, xdp->prog);
+		break;
+	case XDP_QUERY_PROG:
+		xdp->prog_attached = !!bp->xdp_prog;
+		rc = 0;
+		break;
+	default:
+		rc = -EINVAL;
+		break;
+	}
+	return rc;
+}
+#endif
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
new file mode 100644
index 0000000..066a411
--- /dev/null
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
@@ -0,0 +1,28 @@
+/* Broadcom NetXtreme-C/E network driver.
+ *
+ * Copyright (c) 2016-2017 Broadcom Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#ifndef BNXT_XDP_H
+#define BNXT_XDP_H
+
+#ifdef CONFIG_BNXT_XDP
+bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons, void *data,
+		 u8 *data_ptr, unsigned int len, dma_addr_t dma_addr,
+		 u8 *event);
+
+int bnxt_xdp(struct net_device *dev, struct netdev_xdp *xdp);
+
+#else
+static inline bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons,
+			       void *data, u8 *data_ptr, unsigned int len,
+			       dma_addr_t dma_addr, u8 *event)
+{
+	return false;
+}
+#endif
+#endif
-- 
1.8.3.1

Re: [PATCH net-next 09/10] bnxt_en: Add basic XDP support.

[Jakub Kicinski]

On Mon, 30 Jan 2017 20:49:34 -0500, Michael Chan wrote:
> +#ifdef CONFIG_BNXT_XDP
> +/* returns the following:
> + * true    - packet consumed by XDP and new buffer is allocated.
> + * false   - packet should be passed to the stack.
> + */
> +bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons, void *data,
> +		 u8 *data_ptr, unsigned int len, dma_addr_t dma_addr,
> +		 u8 *event)
> +{
> +	struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog);
> +	struct xdp_buff xdp;
> +	u32 act;
> +
> +	if (!xdp_prog)
> +		return false;
> +
> +	xdp.data = data_ptr;
> +	xdp.data_end = xdp.data + len;
> +	rcu_read_lock();
> +	act = bpf_prog_run_xdp(xdp_prog, &xdp);
> +	rcu_read_unlock();
> +
> +	switch (act) {
> +	case XDP_PASS:
> +		return false;
> +
> +	default:
> +		bpf_warn_invalid_xdp_action(act);
> +		/* Fall thru */
> +	case XDP_DROP:
> +	case XDP_ABORTED:
> +		bnxt_reuse_rx_data(rxr, cons, data);
> +		break;
> +	}
> +	return true;
> +}

It would be cool if you could populate the appropriate paths with
tracepoints Daniel added in a67edbf4fb6d ("bpf: add initial bpf
tracepoints").

> +	if (netif_running(dev))
> +		bnxt_close_nic(bp, true, false);
> +
> +	old = xchg(&bp->xdp_prog, prog);
> +	if (old)
> +		bpf_prog_put(old);
> +
> +	if (prog) {
> +		bnxt_set_rx_skb_mode(bp, true);
> +	} else {
> +		bool sh = (bp->flags & BNXT_FLAG_SHARED_RINGS) ? true : false;
> +		int rx, tx;
> +
> +		bnxt_set_rx_skb_mode(bp, false);
> +		bnxt_get_max_rings(bp, &rx, &tx, sh);
> +		if (rx > 1) {
> +			bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS;
> +			bp->dev->hw_features |= NETIF_F_LRO;
> +		}
> +	}
> +	bp->tx_nr_rings_xdp = tx_xdp;
> +	bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp;
> +	bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings);
> +	bp->num_stat_ctxs = bp->cp_nr_rings;
> +	bnxt_set_tpa_flags(bp);
> +	bnxt_set_ring_params(bp);
> +
> +	if (netif_running(dev))
> +		return bnxt_open_nic(bp, true, false);

Mm..  I thought doing open/close like this and risking you won't be
able to come back up was frowned upon [1].  I must be misunderstanding
things...

[1] https://www.spinics.net/lists/netdev/msg365229.html

> +int bnxt_xdp(struct net_device *dev, struct netdev_xdp *xdp)
> +{
> +	struct bnxt *bp = netdev_priv(dev);
> +	int rc;
> +
> +	switch (xdp->command) {
> +	case XDP_SETUP_PROG:
> +		rc = bnxt_xdp_set(bp, xdp->prog);
> +		break;
> +	case XDP_QUERY_PROG:
> +		xdp->prog_attached = !!bp->xdp_prog;
> +		rc = 0;
> +		break;
> +	default:
> +		rc = -EINVAL;
> +		break;
> +	}
> +	return rc;
> +}

Nit: why not simply return?

Re: [PATCH net-next 09/10] bnxt_en: Add basic XDP support.

[Michael Chan]

On Mon, Jan 30, 2017 at 9:04 PM, Jakub Kicinski <kubakici@wp.pl> wrote:
>
>
>> +     if (netif_running(dev))
>> +             bnxt_close_nic(bp, true, false);
>> +
>> +     old = xchg(&bp->xdp_prog, prog);
>> +     if (old)
>> +             bpf_prog_put(old);
>> +
>> +     if (prog) {
>> +             bnxt_set_rx_skb_mode(bp, true);
>> +     } else {
>> +             bool sh = (bp->flags & BNXT_FLAG_SHARED_RINGS) ? true : false;
>> +             int rx, tx;
>> +
>> +             bnxt_set_rx_skb_mode(bp, false);
>> +             bnxt_get_max_rings(bp, &rx, &tx, sh);
>> +             if (rx > 1) {
>> +                     bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS;
>> +                     bp->dev->hw_features |= NETIF_F_LRO;
>> +             }
>> +     }
>> +     bp->tx_nr_rings_xdp = tx_xdp;
>> +     bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp;
>> +     bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings);
>> +     bp->num_stat_ctxs = bp->cp_nr_rings;
>> +     bnxt_set_tpa_flags(bp);
>> +     bnxt_set_ring_params(bp);
>> +
>> +     if (netif_running(dev))
>> +             return bnxt_open_nic(bp, true, false);
>
> Mm..  I thought doing open/close like this and risking you won't be
> able to come back up was frowned upon [1].  I must be misunderstanding
> things...

We take these steps:

1. Check to make sure we have enough rings, MSIX, other resources
first.  If we don't have enough resources, ndo_xdp() will return error
code.  Device is still up.
2. We then call firmware to reserve the rings.  If the firmware call
fails, ndo_xdp() will return error code.  Device is still up.
3. Now we close the device and open the device with additional rings.
Yeah, it is possible the open will fail, but it should be quite
unlikely.  In the event that it fails, the netdev will not be in an
inconsistent state.  It will be in the down state.

[PATCH net-next 10/10] bnxt_en: Add support for XDP_TX action.

[Michael Chan]

Add dedicated transmit function and transmit completion handler for
XDP which are a lot simpler than the original functions for SKB.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Tested-by: Andy Gospodarek <gospo@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 34 +++++-----
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     | 14 +++++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 90 +++++++++++++++++++++++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |  2 +
 4 files changed, 125 insertions(+), 15 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index ae1f400..826915c 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -212,16 +212,7 @@ static bool bnxt_vf_pciid(enum board_idx idx)
 #define BNXT_CP_DB_IRQ_DIS(db)						\
 		writel(DB_CP_IRQ_DIS_FLAGS, db)
 
-static inline u32 bnxt_tx_avail(struct bnxt *bp, struct bnxt_tx_ring_info *txr)
-{
-	/* Tell compiler to fetch tx indices from memory. */
-	barrier();
-
-	return bp->tx_ring_size -
-		((txr->tx_prod - txr->tx_cons) & bp->tx_ring_mask);
-}
-
-static const u16 bnxt_lhint_arr[] = {
+const u16 bnxt_lhint_arr[] = {
 	TX_BD_FLAGS_LHINT_512_AND_SMALLER,
 	TX_BD_FLAGS_LHINT_512_TO_1023,
 	TX_BD_FLAGS_LHINT_1024_TO_2047,
@@ -613,9 +604,8 @@ static inline u8 *__bnxt_alloc_rx_data(struct bnxt *bp, dma_addr_t *mapping,
 	return data;
 }
 
-static inline int bnxt_alloc_rx_data(struct bnxt *bp,
-				     struct bnxt_rx_ring_info *rxr,
-				     u16 prod, gfp_t gfp)
+int bnxt_alloc_rx_data(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
+		       u16 prod, gfp_t gfp)
 {
 	struct rx_bd *rxbd = &rxr->rx_desc_ring[RX_RING(prod)][RX_IDX(prod)];
 	struct bnxt_sw_rx_bd *rx_buf = &rxr->rx_buf_ring[prod];
@@ -1771,6 +1761,17 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 	if (tx_pkts)
 		bnapi->tx_int(bp, bnapi, tx_pkts);
 
+	if (event & BNXT_TX_EVENT) {
+		struct bnxt_tx_ring_info *txr = bnapi->tx_ring;
+		void __iomem *db = txr->tx_doorbell;
+		u16 prod = txr->tx_prod;
+
+		/* Sync BD data before updating doorbell */
+		wmb();
+
+		writel(DB_KEY_TX | prod, db);
+		writel(DB_KEY_TX | prod, db);
+	}
 	if (event & BNXT_RX_EVENT) {
 		struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
 
@@ -3056,9 +3057,12 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 			bp->tx_ring[i].bnapi = bp->bnapi[j];
 			bp->bnapi[j]->tx_ring = &bp->tx_ring[i];
 			bp->tx_ring_map[i] = bp->tx_nr_rings_xdp + i;
-			if (i < bp->tx_nr_rings_xdp)
+			if (i < bp->tx_nr_rings_xdp) {
 				bp->bnapi[j]->flags |= BNXT_NAPI_FLAG_XDP;
-			bp->bnapi[j]->tx_int = bnxt_tx_int;
+				bp->bnapi[j]->tx_int = bnxt_tx_int_xdp;
+			} else {
+				bp->bnapi[j]->tx_int = bnxt_tx_int;
+			}
 		}
 
 		rc = bnxt_alloc_stats(bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 007e779..cf7d33f 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -513,6 +513,7 @@ struct rx_tpa_end_cmp_ext {
 
 #define BNXT_RX_EVENT	1
 #define BNXT_AGG_EVENT	2
+#define BNXT_TX_EVENT	4
 
 struct bnxt_sw_tx_bd {
 	union {
@@ -1190,6 +1191,19 @@ struct bnxt {
 #define SFF_MODULE_ID_QSFP28			0x11
 #define BNXT_MAX_PHY_I2C_RESP_SIZE		64
 
+static inline u32 bnxt_tx_avail(struct bnxt *bp, struct bnxt_tx_ring_info *txr)
+{
+	/* Tell compiler to fetch tx indices from memory. */
+	barrier();
+
+	return bp->tx_ring_size -
+		((txr->tx_prod - txr->tx_cons) & bp->tx_ring_mask);
+}
+
+extern const u16 bnxt_lhint_arr[];
+
+int bnxt_alloc_rx_data(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
+		       u16 prod, gfp_t gfp);
 void bnxt_reuse_rx_data(struct bnxt_rx_ring_info *rxr, u16 cons, void *data);
 void bnxt_set_tpa_flags(struct bnxt *bp);
 void bnxt_set_ring_params(struct bnxt *);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 133e515..a9770ed 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -8,6 +8,7 @@
  */
 #include <linux/kernel.h>
 #include <linux/errno.h>
+#include <linux/pci.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/if_vlan.h>
@@ -18,6 +19,69 @@
 #include "bnxt_xdp.h"
 
 #ifdef CONFIG_BNXT_XDP
+static int bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_napi *bnapi,
+			 struct page *page, dma_addr_t mapping, u32 offset,
+			 u32 len)
+{
+	struct bnxt_tx_ring_info *txr = bnapi->tx_ring;
+	struct bnxt_sw_tx_bd *tx_buf;
+	struct tx_bd_ext *txbd1;
+	struct tx_bd *txbd;
+	u32 flags;
+	u16 prod;
+
+	if (bnxt_tx_avail(bp, txr) < 2)
+		return -ENOSPC;
+
+	prod = txr->tx_prod;
+	txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
+
+	tx_buf = &txr->tx_buf_ring[prod];
+	tx_buf->page = page;
+	dma_unmap_addr_set(tx_buf, mapping, mapping);
+	flags = (len << TX_BD_LEN_SHIFT) | TX_BD_TYPE_LONG_TX_BD |
+		(2 << TX_BD_FLAGS_BD_CNT_SHIFT) | TX_BD_FLAGS_PACKET_END |
+		bnxt_lhint_arr[len >> 9];
+	txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
+	txbd->tx_bd_opaque = prod;
+	txbd->tx_bd_haddr = cpu_to_le64(mapping + offset);
+
+	prod = NEXT_TX(prod);
+	txbd1 = (struct tx_bd_ext *)
+		&txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
+
+	txbd1->tx_bd_hsize_lflags = cpu_to_le32(0);
+	txbd1->tx_bd_mss = cpu_to_le32(0);
+	txbd1->tx_bd_cfa_action = cpu_to_le32(0);
+	txbd1->tx_bd_cfa_meta = cpu_to_le32(0);
+
+	prod = NEXT_TX(prod);
+	txr->tx_prod = prod;
+	return 0;
+}
+
+void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
+{
+	struct bnxt_tx_ring_info *txr = bnapi->tx_ring;
+	struct device *dev = &bp->pdev->dev;
+	u16 cons = txr->tx_cons;
+	int i;
+
+	for (i = 0; i < nr_pkts; i++) {
+		struct bnxt_sw_tx_bd *tx_buf;
+
+		tx_buf = &txr->tx_buf_ring[cons];
+		cons = NEXT_TX(cons);
+		cons = NEXT_TX(cons);
+
+		dma_unmap_page(dev, dma_unmap_addr(tx_buf, mapping), PAGE_SIZE,
+			       bp->rx_dir);
+		__free_page(tx_buf->page);
+		tx_buf->page = NULL;
+	}
+	txr->tx_cons = cons;
+}
+
 /* returns the following:
  * true    - packet consumed by XDP and new buffer is allocated.
  * false   - packet should be passed to the stack.
@@ -43,6 +107,26 @@ bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons, void *data,
 	case XDP_PASS:
 		return false;
 
+	case XDP_TX: {
+		struct bnxt_napi *bnapi = rxr->bnapi;
+		struct bnxt *bp = bnapi->bp;
+		int rc;
+
+		rc = bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC);
+		if (unlikely(rc)) {
+			bnxt_reuse_rx_data(rxr, cons, data);
+			return true;
+		}
+		if (bnxt_xmit_xdp(bp, bnapi, data, dma_addr, NET_IP_ALIGN,
+				  len)) {
+			dma_unmap_page(&bp->pdev->dev, dma_addr, PAGE_SIZE,
+				       bp->rx_dir);
+			__free_page(data);
+			return true;
+		}
+		*event |= BNXT_TX_EVENT;
+		return true;
+	}
 	default:
 		bpf_warn_invalid_xdp_action(act);
 		/* Fall thru */
@@ -138,4 +222,10 @@ int bnxt_xdp(struct net_device *dev, struct netdev_xdp *xdp)
 	}
 	return rc;
 }
+
+#else
+
+void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
+{
+}
 #endif
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
index 066a411..835eca5 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
@@ -10,6 +10,8 @@
 #ifndef BNXT_XDP_H
 #define BNXT_XDP_H
 
+void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts);
+
 #ifdef CONFIG_BNXT_XDP
 bool bnxt_rx_xdp(struct bnxt_rx_ring_info *rxr, u16 cons, void *data,
 		 u8 *data_ptr, unsigned int len, dma_addr_t dma_addr,
-- 
1.8.3.1

Re: [PATCH net-next 10/10] bnxt_en: Add support for XDP_TX action.

[Jakub Kicinski]

On Mon, 30 Jan 2017 20:49:35 -0500, Michael Chan wrote:
> +static int bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_napi *bnapi,
> +			 struct page *page, dma_addr_t mapping, u32 offset,
> +			 u32 len)
> +{
> +	struct bnxt_tx_ring_info *txr = bnapi->tx_ring;
> +	struct bnxt_sw_tx_bd *tx_buf;
> +	struct tx_bd_ext *txbd1;
> +	struct tx_bd *txbd;
> +	u32 flags;
> +	u16 prod;
> +
> +	if (bnxt_tx_avail(bp, txr) < 2)
> +		return -ENOSPC;
> +
> +	prod = txr->tx_prod;
> +	txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
> +
> +	tx_buf = &txr->tx_buf_ring[prod];
> +	tx_buf->page = page;
> +	dma_unmap_addr_set(tx_buf, mapping, mapping);
> +	flags = (len << TX_BD_LEN_SHIFT) | TX_BD_TYPE_LONG_TX_BD |
> +		(2 << TX_BD_FLAGS_BD_CNT_SHIFT) | TX_BD_FLAGS_PACKET_END |
> +		bnxt_lhint_arr[len >> 9];
> +	txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
> +	txbd->tx_bd_opaque = prod;
> +	txbd->tx_bd_haddr = cpu_to_le64(mapping + offset);
> +
> +	prod = NEXT_TX(prod);
> +	txbd1 = (struct tx_bd_ext *)
> +		&txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
> +
> +	txbd1->tx_bd_hsize_lflags = cpu_to_le32(0);
> +	txbd1->tx_bd_mss = cpu_to_le32(0);
> +	txbd1->tx_bd_cfa_action = cpu_to_le32(0);
> +	txbd1->tx_bd_cfa_meta = cpu_to_le32(0);
> +
> +	prod = NEXT_TX(prod);
> +	txr->tx_prod = prod;
> +	return 0;
> +}

Are you not lacking DMA syncs in general?  You map the buffers
bidirectionally, but I failed to find any dma_syncs.  I would expect
one before you run xdp and one before you TX because packet could have
been modified.  What am I missing?

Re: [PATCH net-next 10/10] bnxt_en: Add support for XDP_TX action.

[Michael Chan]

On Mon, Jan 30, 2017 at 9:27 PM, Jakub Kicinski <kubakici@wp.pl> wrote:
> On Mon, 30 Jan 2017 20:49:35 -0500, Michael Chan wrote:
>> +static int bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_napi *bnapi,
>> +                      struct page *page, dma_addr_t mapping, u32 offset,
>> +                      u32 len)
>> +{
>> +     struct bnxt_tx_ring_info *txr = bnapi->tx_ring;
>> +     struct bnxt_sw_tx_bd *tx_buf;
>> +     struct tx_bd_ext *txbd1;
>> +     struct tx_bd *txbd;
>> +     u32 flags;
>> +     u16 prod;
>> +
>> +     if (bnxt_tx_avail(bp, txr) < 2)
>> +             return -ENOSPC;
>> +
>> +     prod = txr->tx_prod;
>> +     txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
>> +
>> +     tx_buf = &txr->tx_buf_ring[prod];
>> +     tx_buf->page = page;
>> +     dma_unmap_addr_set(tx_buf, mapping, mapping);
>> +     flags = (len << TX_BD_LEN_SHIFT) | TX_BD_TYPE_LONG_TX_BD |
>> +             (2 << TX_BD_FLAGS_BD_CNT_SHIFT) | TX_BD_FLAGS_PACKET_END |
>> +             bnxt_lhint_arr[len >> 9];
>> +     txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
>> +     txbd->tx_bd_opaque = prod;
>> +     txbd->tx_bd_haddr = cpu_to_le64(mapping + offset);
>> +
>> +     prod = NEXT_TX(prod);
>> +     txbd1 = (struct tx_bd_ext *)
>> +             &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
>> +
>> +     txbd1->tx_bd_hsize_lflags = cpu_to_le32(0);
>> +     txbd1->tx_bd_mss = cpu_to_le32(0);
>> +     txbd1->tx_bd_cfa_action = cpu_to_le32(0);
>> +     txbd1->tx_bd_cfa_meta = cpu_to_le32(0);
>> +
>> +     prod = NEXT_TX(prod);
>> +     txr->tx_prod = prod;
>> +     return 0;
>> +}
>
> Are you not lacking DMA syncs in general?  You map the buffers
> bidirectionally, but I failed to find any dma_syncs.  I would expect
> one before you run xdp and one before you TX because packet could have
> been modified.  What am I missing?

You are right.  I missed the DMA syncs.

Re: [PATCH net-next 00/10] bnxt_en: Add XDP support.

[Alexei Starovoitov]

On Mon, Jan 30, 2017 at 08:49:25PM -0500, Michael Chan wrote:
> The first 8 patches refactor the code (rx/tx code paths and ring logic)
> and add the basic infrastructure to support XDP.  The 9th patch adds
> basic ndo_xdp to support XDP_DROP and XDP_PASS only.  The 10th patch
> completes the series with XDP_TX.

Looks great.
Could you please share performance numbers ?

Also please add something like:
  if (prog && prog->xdp_adjust_head) {
          netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
          return -EOPNOTSUPP;
  }
unless you plan to add adjut_head support until net-next closes.
Note, it's must have for load balancer functionality.

Re: [PATCH net-next 00/10] bnxt_en: Add XDP support.

[Jakub Kicinski]

On Mon, 30 Jan 2017 20:47:47 -0800, Alexei Starovoitov wrote:
> On Mon, Jan 30, 2017 at 08:49:25PM -0500, Michael Chan wrote:
> > The first 8 patches refactor the code (rx/tx code paths and ring logic)
> > and add the basic infrastructure to support XDP.  The 9th patch adds
> > basic ndo_xdp to support XDP_DROP and XDP_PASS only.  The 10th patch
> > completes the series with XDP_TX.  
> 
> Looks great.
> Could you please share performance numbers ?
> 
> Also please add something like:
>   if (prog && prog->xdp_adjust_head) {
>           netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
>           return -EOPNOTSUPP;
>   }
> unless you plan to add adjut_head support until net-next closes.
> Note, it's must have for load balancer functionality.

I was about to ask whether it's OK at this point to add XDP support
without xdp_adjust_head()?  My understanding was that this is basic
functionality and therefore required?

FWIW the check you requested is there in patch 9.

Re: [PATCH net-next 00/10] bnxt_en: Add XDP support.

[Michael Chan]

On Mon, Jan 30, 2017 at 9:13 PM, Jakub Kicinski <kubakici@wp.pl> wrote:
> On Mon, 30 Jan 2017 20:47:47 -0800, Alexei Starovoitov wrote:
>> On Mon, Jan 30, 2017 at 08:49:25PM -0500, Michael Chan wrote:
>> > The first 8 patches refactor the code (rx/tx code paths and ring logic)
>> > and add the basic infrastructure to support XDP.  The 9th patch adds
>> > basic ndo_xdp to support XDP_DROP and XDP_PASS only.  The 10th patch
>> > completes the series with XDP_TX.
>>
>> Looks great.
>> Could you please share performance numbers ?
>>
>> Also please add something like:
>>   if (prog && prog->xdp_adjust_head) {
>>           netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
>>           return -EOPNOTSUPP;
>>   }
>> unless you plan to add adjut_head support until net-next closes.
>> Note, it's must have for load balancer functionality.
>
> I was about to ask whether it's OK at this point to add XDP support
> without xdp_adjust_head()?  My understanding was that this is basic
> functionality and therefore required?

I need to first figure out what xdp_adjust_head means.  If it is ok,
I'd like to defer it.

>
> FWIW the check you requested is there in patch 9.

Yes, it is in there.  I just copied the same code from other drivers.