From 123cecd427b6c1af5bdc3a90131ae85581854319 Mon Sep 17 00:00:00 2001
From: Björn Töpel <bjorn.topel@intel.com>
Date: Tue, 28 Aug 2018 14:44:29 +0200
Subject: i40e: added queue pair disable/enable functions
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add functions for queue pair enable/disable. Instead of resetting the
whole device, only the affected queue pair is disabled or enabled.

This plumbing is used in a later commit, when zero-copy AF_XDP support
is introduced.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 250 ++++++++++++++++++++++++++++
 1 file changed, 250 insertions(+)

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index ac685ad4d877..d8b5a6af72bd 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -11827,6 +11827,256 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi,
 	return 0;
 }
 
+/**
+ * i40e_enter_busy_conf - Enters busy config state
+ * @vsi: vsi
+ *
+ * Returns 0 on success, <0 for failure.
+ **/
+static int i40e_enter_busy_conf(struct i40e_vsi *vsi)
+{
+	struct i40e_pf *pf = vsi->back;
+	int timeout = 50;
+
+	while (test_and_set_bit(__I40E_CONFIG_BUSY, pf->state)) {
+		timeout--;
+		if (!timeout)
+			return -EBUSY;
+		usleep_range(1000, 2000);
+	}
+
+	return 0;
+}
+
+/**
+ * i40e_exit_busy_conf - Exits busy config state
+ * @vsi: vsi
+ **/
+static void i40e_exit_busy_conf(struct i40e_vsi *vsi)
+{
+	struct i40e_pf *pf = vsi->back;
+
+	clear_bit(__I40E_CONFIG_BUSY, pf->state);
+}
+
+/**
+ * i40e_queue_pair_reset_stats - Resets all statistics for a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ **/
+static void i40e_queue_pair_reset_stats(struct i40e_vsi *vsi, int queue_pair)
+{
+	memset(&vsi->rx_rings[queue_pair]->rx_stats, 0,
+	       sizeof(vsi->rx_rings[queue_pair]->rx_stats));
+	memset(&vsi->tx_rings[queue_pair]->stats, 0,
+	       sizeof(vsi->tx_rings[queue_pair]->stats));
+	if (i40e_enabled_xdp_vsi(vsi)) {
+		memset(&vsi->xdp_rings[queue_pair]->stats, 0,
+		       sizeof(vsi->xdp_rings[queue_pair]->stats));
+	}
+}
+
+/**
+ * i40e_queue_pair_clean_rings - Cleans all the rings of a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ **/
+static void i40e_queue_pair_clean_rings(struct i40e_vsi *vsi, int queue_pair)
+{
+	i40e_clean_tx_ring(vsi->tx_rings[queue_pair]);
+	if (i40e_enabled_xdp_vsi(vsi))
+		i40e_clean_tx_ring(vsi->xdp_rings[queue_pair]);
+	i40e_clean_rx_ring(vsi->rx_rings[queue_pair]);
+}
+
+/**
+ * i40e_queue_pair_toggle_napi - Enables/disables NAPI for a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ * @enable: true for enable, false for disable
+ **/
+static void i40e_queue_pair_toggle_napi(struct i40e_vsi *vsi, int queue_pair,
+					bool enable)
+{
+	struct i40e_ring *rxr = vsi->rx_rings[queue_pair];
+	struct i40e_q_vector *q_vector = rxr->q_vector;
+
+	if (!vsi->netdev)
+		return;
+
+	/* All rings in a qp belong to the same qvector. */
+	if (q_vector->rx.ring || q_vector->tx.ring) {
+		if (enable)
+			napi_enable(&q_vector->napi);
+		else
+			napi_disable(&q_vector->napi);
+	}
+}
+
+/**
+ * i40e_queue_pair_toggle_rings - Enables/disables all rings for a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ * @enable: true for enable, false for disable
+ *
+ * Returns 0 on success, <0 on failure.
+ **/
+static int i40e_queue_pair_toggle_rings(struct i40e_vsi *vsi, int queue_pair,
+					bool enable)
+{
+	struct i40e_pf *pf = vsi->back;
+	int pf_q, ret = 0;
+
+	pf_q = vsi->base_queue + queue_pair;
+	ret = i40e_control_wait_tx_q(vsi->seid, pf, pf_q,
+				     false /*is xdp*/, enable);
+	if (ret) {
+		dev_info(&pf->pdev->dev,
+			 "VSI seid %d Tx ring %d %sable timeout\n",
+			 vsi->seid, pf_q, (enable ? "en" : "dis"));
+		return ret;
+	}
+
+	i40e_control_rx_q(pf, pf_q, enable);
+	ret = i40e_pf_rxq_wait(pf, pf_q, enable);
+	if (ret) {
+		dev_info(&pf->pdev->dev,
+			 "VSI seid %d Rx ring %d %sable timeout\n",
+			 vsi->seid, pf_q, (enable ? "en" : "dis"));
+		return ret;
+	}
+
+	/* Due to HW errata, on Rx disable only, the register can
+	 * indicate done before it really is. Needs 50ms to be sure
+	 */
+	if (!enable)
+		mdelay(50);
+
+	if (!i40e_enabled_xdp_vsi(vsi))
+		return ret;
+
+	ret = i40e_control_wait_tx_q(vsi->seid, pf,
+				     pf_q + vsi->alloc_queue_pairs,
+				     true /*is xdp*/, enable);
+	if (ret) {
+		dev_info(&pf->pdev->dev,
+			 "VSI seid %d XDP Tx ring %d %sable timeout\n",
+			 vsi->seid, pf_q, (enable ? "en" : "dis"));
+	}
+
+	return ret;
+}
+
+/**
+ * i40e_queue_pair_enable_irq - Enables interrupts for a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue_pair
+ **/
+static void i40e_queue_pair_enable_irq(struct i40e_vsi *vsi, int queue_pair)
+{
+	struct i40e_ring *rxr = vsi->rx_rings[queue_pair];
+	struct i40e_pf *pf = vsi->back;
+	struct i40e_hw *hw = &pf->hw;
+
+	/* All rings in a qp belong to the same qvector. */
+	if (pf->flags & I40E_FLAG_MSIX_ENABLED)
+		i40e_irq_dynamic_enable(vsi, rxr->q_vector->v_idx);
+	else
+		i40e_irq_dynamic_enable_icr0(pf);
+
+	i40e_flush(hw);
+}
+
+/**
+ * i40e_queue_pair_disable_irq - Disables interrupts for a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue_pair
+ **/
+static void i40e_queue_pair_disable_irq(struct i40e_vsi *vsi, int queue_pair)
+{
+	struct i40e_ring *rxr = vsi->rx_rings[queue_pair];
+	struct i40e_pf *pf = vsi->back;
+	struct i40e_hw *hw = &pf->hw;
+
+	/* For simplicity, instead of removing the qp interrupt causes
+	 * from the interrupt linked list, we simply disable the interrupt, and
+	 * leave the list intact.
+	 *
+	 * All rings in a qp belong to the same qvector.
+	 */
+	if (pf->flags & I40E_FLAG_MSIX_ENABLED) {
+		u32 intpf = vsi->base_vector + rxr->q_vector->v_idx;
+
+		wr32(hw, I40E_PFINT_DYN_CTLN(intpf - 1), 0);
+		i40e_flush(hw);
+		synchronize_irq(pf->msix_entries[intpf].vector);
+	} else {
+		/* Legacy and MSI mode - this stops all interrupt handling */
+		wr32(hw, I40E_PFINT_ICR0_ENA, 0);
+		wr32(hw, I40E_PFINT_DYN_CTL0, 0);
+		i40e_flush(hw);
+		synchronize_irq(pf->pdev->irq);
+	}
+}
+
+/**
+ * i40e_queue_pair_disable - Disables a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ *
+ * Returns 0 on success, <0 on failure.
+ **/
+int i40e_queue_pair_disable(struct i40e_vsi *vsi, int queue_pair)
+{
+	int err;
+
+	err = i40e_enter_busy_conf(vsi);
+	if (err)
+		return err;
+
+	i40e_queue_pair_disable_irq(vsi, queue_pair);
+	err = i40e_queue_pair_toggle_rings(vsi, queue_pair, false /* off */);
+	i40e_queue_pair_toggle_napi(vsi, queue_pair, false /* off */);
+	i40e_queue_pair_clean_rings(vsi, queue_pair);
+	i40e_queue_pair_reset_stats(vsi, queue_pair);
+
+	return err;
+}
+
+/**
+ * i40e_queue_pair_enable - Enables a queue pair
+ * @vsi: vsi
+ * @queue_pair: queue pair
+ *
+ * Returns 0 on success, <0 on failure.
+ **/
+int i40e_queue_pair_enable(struct i40e_vsi *vsi, int queue_pair)
+{
+	int err;
+
+	err = i40e_configure_tx_ring(vsi->tx_rings[queue_pair]);
+	if (err)
+		return err;
+
+	if (i40e_enabled_xdp_vsi(vsi)) {
+		err = i40e_configure_tx_ring(vsi->xdp_rings[queue_pair]);
+		if (err)
+			return err;
+	}
+
+	err = i40e_configure_rx_ring(vsi->rx_rings[queue_pair]);
+	if (err)
+		return err;
+
+	err = i40e_queue_pair_toggle_rings(vsi, queue_pair, true /* on */);
+	i40e_queue_pair_toggle_napi(vsi, queue_pair, true /* on */);
+	i40e_queue_pair_enable_irq(vsi, queue_pair);
+
+	i40e_exit_busy_conf(vsi);
+
+	return err;
+}
+
 /**
  * i40e_xdp - implements ndo_bpf for i40e
  * @dev: netdevice
-- 
cgit v1.2.3-59-g8ed1b


From 6d7aad1da2791cc0863a5b8068dcdb8c7536519d Mon Sep 17 00:00:00 2001
From: Björn Töpel <bjorn.topel@intel.com>
Date: Tue, 28 Aug 2018 14:44:30 +0200
Subject: i40e: refactor Rx path for re-use
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

In this commit, the Rx path is refactored some, as a step torwards the
introduction AF_XDP Rx zero-copy.

The page re-use counter is moved into the i40e_reuse_rx_page, instead
of bumping the counter in many places. The Rx buffer page clearing is
moved for better readability. Lastely, functions to update statistics
and bump the XDP Tx ring are introduced.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_txrx.c | 111 +++++++++++++++++++---------
 1 file changed, 77 insertions(+), 34 deletions(-)

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index b5042d1a63c0..b5a2cfeb68a5 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -1244,6 +1244,11 @@ static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
 	new_buff->page		= old_buff->page;
 	new_buff->page_offset	= old_buff->page_offset;
 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
+
+	rx_ring->rx_stats.page_reuse_count++;
+
+	/* clear contents of buffer_info */
+	old_buff->page = NULL;
 }
 
 /**
@@ -1266,7 +1271,7 @@ static inline bool i40e_rx_is_programming_status(u64 qw)
 }
 
 /**
- * i40e_clean_programming_status - clean the programming status descriptor
+ * i40e_clean_programming_status - try clean the programming status descriptor
  * @rx_ring: the rx ring that has this descriptor
  * @rx_desc: the rx descriptor written back by HW
  * @qw: qword representing status_error_len in CPU ordering
@@ -1275,15 +1280,22 @@ static inline bool i40e_rx_is_programming_status(u64 qw)
  * status being successful or not and take actions accordingly. FCoE should
  * handle its context/filter programming/invalidation status and take actions.
  *
+ * Returns an i40e_rx_buffer to reuse if the cleanup occurred, otherwise NULL.
  **/
-static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
-					  union i40e_rx_desc *rx_desc,
-					  u64 qw)
+static struct i40e_rx_buffer *i40e_clean_programming_status(
+	struct i40e_ring *rx_ring,
+	union i40e_rx_desc *rx_desc,
+	u64 qw)
 {
 	struct i40e_rx_buffer *rx_buffer;
-	u32 ntc = rx_ring->next_to_clean;
+	u32 ntc;
 	u8 id;
 
+	if (!i40e_rx_is_programming_status(qw))
+		return NULL;
+
+	ntc = rx_ring->next_to_clean;
+
 	/* fetch, update, and store next to clean */
 	rx_buffer = &rx_ring->rx_bi[ntc++];
 	ntc = (ntc < rx_ring->count) ? ntc : 0;
@@ -1291,18 +1303,13 @@ static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
 
 	prefetch(I40E_RX_DESC(rx_ring, ntc));
 
-	/* place unused page back on the ring */
-	i40e_reuse_rx_page(rx_ring, rx_buffer);
-	rx_ring->rx_stats.page_reuse_count++;
-
-	/* clear contents of buffer_info */
-	rx_buffer->page = NULL;
-
 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
 
 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
 		i40e_fd_handle_status(rx_ring, rx_desc, id);
+
+	return rx_buffer;
 }
 
 /**
@@ -2152,7 +2159,6 @@ static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
 	if (i40e_can_reuse_rx_page(rx_buffer)) {
 		/* hand second half of page back to the ring */
 		i40e_reuse_rx_page(rx_ring, rx_buffer);
-		rx_ring->rx_stats.page_reuse_count++;
 	} else {
 		/* we are not reusing the buffer so unmap it */
 		dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
@@ -2160,10 +2166,9 @@ static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
 				     DMA_FROM_DEVICE, I40E_RX_DMA_ATTR);
 		__page_frag_cache_drain(rx_buffer->page,
 					rx_buffer->pagecnt_bias);
+		/* clear contents of buffer_info */
+		rx_buffer->page = NULL;
 	}
-
-	/* clear contents of buffer_info */
-	rx_buffer->page = NULL;
 }
 
 /**
@@ -2287,6 +2292,12 @@ static void i40e_rx_buffer_flip(struct i40e_ring *rx_ring,
 #endif
 }
 
+/**
+ * i40e_xdp_ring_update_tail - Updates the XDP Tx ring tail register
+ * @xdp_ring: XDP Tx ring
+ *
+ * This function updates the XDP Tx ring tail register.
+ **/
 static inline void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
 {
 	/* Force memory writes to complete before letting h/w
@@ -2296,6 +2307,49 @@ static inline void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
 	writel_relaxed(xdp_ring->next_to_use, xdp_ring->tail);
 }
 
+/**
+ * i40e_update_rx_stats - Update Rx ring statistics
+ * @rx_ring: rx descriptor ring
+ * @total_rx_bytes: number of bytes received
+ * @total_rx_packets: number of packets received
+ *
+ * This function updates the Rx ring statistics.
+ **/
+static void i40e_update_rx_stats(struct i40e_ring *rx_ring,
+				 unsigned int total_rx_bytes,
+				 unsigned int total_rx_packets)
+{
+	u64_stats_update_begin(&rx_ring->syncp);
+	rx_ring->stats.packets += total_rx_packets;
+	rx_ring->stats.bytes += total_rx_bytes;
+	u64_stats_update_end(&rx_ring->syncp);
+	rx_ring->q_vector->rx.total_packets += total_rx_packets;
+	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
+}
+
+/**
+ * i40e_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
+ * @rx_ring: Rx ring
+ * @xdp_res: Result of the receive batch
+ *
+ * This function bumps XDP Tx tail and/or flush redirect map, and
+ * should be called when a batch of packets has been processed in the
+ * napi loop.
+ **/
+static void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring,
+				 unsigned int xdp_res)
+{
+	if (xdp_res & I40E_XDP_REDIR)
+		xdp_do_flush_map();
+
+	if (xdp_res & I40E_XDP_TX) {
+		struct i40e_ring *xdp_ring =
+			rx_ring->vsi->xdp_rings[rx_ring->queue_index];
+
+		i40e_xdp_ring_update_tail(xdp_ring);
+	}
+}
+
 /**
  * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
  * @rx_ring: rx descriptor ring to transact packets on
@@ -2349,11 +2403,14 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 		 */
 		dma_rmb();
 
-		if (unlikely(i40e_rx_is_programming_status(qword))) {
-			i40e_clean_programming_status(rx_ring, rx_desc, qword);
+		rx_buffer = i40e_clean_programming_status(rx_ring, rx_desc,
+							  qword);
+		if (unlikely(rx_buffer)) {
+			i40e_reuse_rx_page(rx_ring, rx_buffer);
 			cleaned_count++;
 			continue;
 		}
+
 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
 		if (!size)
@@ -2432,24 +2489,10 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 		total_rx_packets++;
 	}
 
-	if (xdp_xmit & I40E_XDP_REDIR)
-		xdp_do_flush_map();
-
-	if (xdp_xmit & I40E_XDP_TX) {
-		struct i40e_ring *xdp_ring =
-			rx_ring->vsi->xdp_rings[rx_ring->queue_index];
-
-		i40e_xdp_ring_update_tail(xdp_ring);
-	}
-
+	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
 	rx_ring->skb = skb;
 
-	u64_stats_update_begin(&rx_ring->syncp);
-	rx_ring->stats.packets += total_rx_packets;
-	rx_ring->stats.bytes += total_rx_bytes;
-	u64_stats_update_end(&rx_ring->syncp);
-	rx_ring->q_vector->rx.total_packets += total_rx_packets;
-	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
+	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
 
 	/* guarantee a trip back through this routine if there was a failure */
 	return failure ? budget : (int)total_rx_packets;
-- 
cgit v1.2.3-59-g8ed1b


From 20a739dbef28fb3c17de2789a3d7847efec6a3ff Mon Sep 17 00:00:00 2001
From: Björn Töpel <bjorn.topel@intel.com>
Date: Tue, 28 Aug 2018 14:44:31 +0200
Subject: i40e: move common Rx functions to i40e_txrx_common.h
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This patch prepares for the upcoming zero-copy Rx functionality, by
moving/changing linkage of common functions, used both by the regular
path and zero-copy path.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_txrx.c        | 33 +++++++++-------------
 drivers/net/ethernet/intel/i40e/i40e_txrx_common.h | 31 ++++++++++++++++++++
 2 files changed, 44 insertions(+), 20 deletions(-)
 create mode 100644 drivers/net/ethernet/intel/i40e/i40e_txrx_common.h

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index b5a2cfeb68a5..878fb4b47484 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -8,6 +8,7 @@
 #include "i40e.h"
 #include "i40e_trace.h"
 #include "i40e_prototype.h"
+#include "i40e_txrx_common.h"
 
 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
 				u32 td_tag)
@@ -536,8 +537,8 @@ int i40e_add_del_fdir(struct i40e_vsi *vsi,
  * This is used to verify if the FD programming or invalidation
  * requested by SW to the HW is successful or not and take actions accordingly.
  **/
-static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
-				  union i40e_rx_desc *rx_desc, u8 prog_id)
+void i40e_fd_handle_status(struct i40e_ring *rx_ring,
+			   union i40e_rx_desc *rx_desc, u8 prog_id)
 {
 	struct i40e_pf *pf = rx_ring->vsi->back;
 	struct pci_dev *pdev = pf->pdev;
@@ -1282,7 +1283,7 @@ static inline bool i40e_rx_is_programming_status(u64 qw)
  *
  * Returns an i40e_rx_buffer to reuse if the cleanup occurred, otherwise NULL.
  **/
-static struct i40e_rx_buffer *i40e_clean_programming_status(
+struct i40e_rx_buffer *i40e_clean_programming_status(
 	struct i40e_ring *rx_ring,
 	union i40e_rx_desc *rx_desc,
 	u64 qw)
@@ -1499,7 +1500,7 @@ err:
  * @rx_ring: ring to bump
  * @val: new head index
  **/
-static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
+void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
 {
 	rx_ring->next_to_use = val;
 
@@ -1583,8 +1584,8 @@ static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
  * @skb: packet to send up
  * @vlan_tag: vlan tag for packet
  **/
-static void i40e_receive_skb(struct i40e_ring *rx_ring,
-			     struct sk_buff *skb, u16 vlan_tag)
+void i40e_receive_skb(struct i40e_ring *rx_ring,
+		      struct sk_buff *skb, u16 vlan_tag)
 {
 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
 
@@ -1811,7 +1812,6 @@ static inline void i40e_rx_hash(struct i40e_ring *ring,
  * order to populate the hash, checksum, VLAN, protocol, and
  * other fields within the skb.
  **/
-static inline
 void i40e_process_skb_fields(struct i40e_ring *rx_ring,
 			     union i40e_rx_desc *rx_desc, struct sk_buff *skb,
 			     u8 rx_ptype)
@@ -2204,16 +2204,10 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
 	return true;
 }
 
-#define I40E_XDP_PASS		0
-#define I40E_XDP_CONSUMED	BIT(0)
-#define I40E_XDP_TX		BIT(1)
-#define I40E_XDP_REDIR		BIT(2)
-
 static int i40e_xmit_xdp_ring(struct xdp_frame *xdpf,
 			      struct i40e_ring *xdp_ring);
 
-static int i40e_xmit_xdp_tx_ring(struct xdp_buff *xdp,
-				 struct i40e_ring *xdp_ring)
+int i40e_xmit_xdp_tx_ring(struct xdp_buff *xdp, struct i40e_ring *xdp_ring)
 {
 	struct xdp_frame *xdpf = convert_to_xdp_frame(xdp);
 
@@ -2298,7 +2292,7 @@ static void i40e_rx_buffer_flip(struct i40e_ring *rx_ring,
  *
  * This function updates the XDP Tx ring tail register.
  **/
-static inline void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
+void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
 {
 	/* Force memory writes to complete before letting h/w
 	 * know there are new descriptors to fetch.
@@ -2315,9 +2309,9 @@ static inline void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
  *
  * This function updates the Rx ring statistics.
  **/
-static void i40e_update_rx_stats(struct i40e_ring *rx_ring,
-				 unsigned int total_rx_bytes,
-				 unsigned int total_rx_packets)
+void i40e_update_rx_stats(struct i40e_ring *rx_ring,
+			  unsigned int total_rx_bytes,
+			  unsigned int total_rx_packets)
 {
 	u64_stats_update_begin(&rx_ring->syncp);
 	rx_ring->stats.packets += total_rx_packets;
@@ -2336,8 +2330,7 @@ static void i40e_update_rx_stats(struct i40e_ring *rx_ring,
  * should be called when a batch of packets has been processed in the
  * napi loop.
  **/
-static void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring,
-				 unsigned int xdp_res)
+void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring, unsigned int xdp_res)
 {
 	if (xdp_res & I40E_XDP_REDIR)
 		xdp_do_flush_map();
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
new file mode 100644
index 000000000000..2bd5187fcd66
--- /dev/null
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright(c) 2018 Intel Corporation. */
+
+#ifndef I40E_TXRX_COMMON_
+#define I40E_TXRX_COMMON_
+
+void i40e_fd_handle_status(struct i40e_ring *rx_ring,
+			   union i40e_rx_desc *rx_desc, u8 prog_id);
+int i40e_xmit_xdp_tx_ring(struct xdp_buff *xdp, struct i40e_ring *xdp_ring);
+struct i40e_rx_buffer *i40e_clean_programming_status(
+	struct i40e_ring *rx_ring,
+	union i40e_rx_desc *rx_desc,
+	u64 qw);
+void i40e_process_skb_fields(struct i40e_ring *rx_ring,
+			     union i40e_rx_desc *rx_desc, struct sk_buff *skb,
+			     u8 rx_ptype);
+void i40e_receive_skb(struct i40e_ring *rx_ring,
+		      struct sk_buff *skb, u16 vlan_tag);
+void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring);
+void i40e_update_rx_stats(struct i40e_ring *rx_ring,
+			  unsigned int total_rx_bytes,
+			  unsigned int total_rx_packets);
+void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring, unsigned int xdp_res);
+void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val);
+
+#define I40E_XDP_PASS		0
+#define I40E_XDP_CONSUMED	BIT(0)
+#define I40E_XDP_TX		BIT(1)
+#define I40E_XDP_REDIR		BIT(2)
+
+#endif /* I40E_TXRX_COMMON_ */
-- 
cgit v1.2.3-59-g8ed1b


From 0a714186d3c0f7c563a03537f98716457c1f5ae0 Mon Sep 17 00:00:00 2001
From: Björn Töpel <bjorn.topel@intel.com>
Date: Tue, 28 Aug 2018 14:44:32 +0200
Subject: i40e: add AF_XDP zero-copy Rx support
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This patch adds zero-copy Rx support for AF_XDP sockets. Instead of
allocating buffers of type MEM_TYPE_PAGE_SHARED, the Rx frames are
allocated as MEM_TYPE_ZERO_COPY when AF_XDP is enabled for a certain
queue.

All AF_XDP specific functions are added to a new file, i40e_xsk.c.

Note that when AF_XDP zero-copy is enabled, the XDP action XDP_PASS
will allocate a new buffer and copy the zero-copy frame prior passing
it to the kernel stack.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/Makefile    |   3 +-
 drivers/net/ethernet/intel/i40e/i40e.h      |  19 +
 drivers/net/ethernet/intel/i40e/i40e_main.c |  53 ++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c |   9 +-
 drivers/net/ethernet/intel/i40e/i40e_txrx.h |  20 +-
 drivers/net/ethernet/intel/i40e/i40e_xsk.c  | 661 ++++++++++++++++++++++++++++
 drivers/net/ethernet/intel/i40e/i40e_xsk.h  |  21 +
 7 files changed, 775 insertions(+), 11 deletions(-)
 create mode 100644 drivers/net/ethernet/intel/i40e/i40e_xsk.c
 create mode 100644 drivers/net/ethernet/intel/i40e/i40e_xsk.h

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/Makefile b/drivers/net/ethernet/intel/i40e/Makefile
index 14397e7e9925..50590e8d1fd1 100644
--- a/drivers/net/ethernet/intel/i40e/Makefile
+++ b/drivers/net/ethernet/intel/i40e/Makefile
@@ -22,6 +22,7 @@ i40e-objs := i40e_main.o \
 	i40e_txrx.o	\
 	i40e_ptp.o	\
 	i40e_client.o   \
-	i40e_virtchnl_pf.o
+	i40e_virtchnl_pf.o \
+	i40e_xsk.o
 
 i40e-$(CONFIG_I40E_DCB) += i40e_dcb.o i40e_dcb_nl.o
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 7a80652e2500..876cac317e79 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -786,6 +786,11 @@ struct i40e_vsi {
 
 	/* VSI specific handlers */
 	irqreturn_t (*irq_handler)(int irq, void *data);
+
+	/* AF_XDP zero-copy */
+	struct xdp_umem **xsk_umems;
+	u16 num_xsk_umems_used;
+	u16 num_xsk_umems;
 } ____cacheline_internodealigned_in_smp;
 
 struct i40e_netdev_priv {
@@ -1090,6 +1095,20 @@ static inline bool i40e_enabled_xdp_vsi(struct i40e_vsi *vsi)
 	return !!vsi->xdp_prog;
 }
 
+static inline struct xdp_umem *i40e_xsk_umem(struct i40e_ring *ring)
+{
+	bool xdp_on = i40e_enabled_xdp_vsi(ring->vsi);
+	int qid = ring->queue_index;
+
+	if (ring_is_xdp(ring))
+		qid -= ring->vsi->alloc_queue_pairs;
+
+	if (!ring->vsi->xsk_umems || !ring->vsi->xsk_umems[qid] || !xdp_on)
+		return NULL;
+
+	return ring->vsi->xsk_umems[qid];
+}
+
 int i40e_create_queue_channel(struct i40e_vsi *vsi, struct i40e_channel *ch);
 int i40e_set_bw_limit(struct i40e_vsi *vsi, u16 seid, u64 max_tx_rate);
 int i40e_add_del_cloud_filter(struct i40e_vsi *vsi,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index d8b5a6af72bd..848eea7c84db 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -9,7 +9,9 @@
 /* Local includes */
 #include "i40e.h"
 #include "i40e_diag.h"
+#include "i40e_xsk.h"
 #include <net/udp_tunnel.h>
+#include <net/xdp_sock.h>
 /* All i40e tracepoints are defined by the include below, which
  * must be included exactly once across the whole kernel with
  * CREATE_TRACE_POINTS defined
@@ -3181,13 +3183,46 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
 	struct i40e_hw *hw = &vsi->back->hw;
 	struct i40e_hmc_obj_rxq rx_ctx;
 	i40e_status err = 0;
+	bool ok;
+	int ret;
 
 	bitmap_zero(ring->state, __I40E_RING_STATE_NBITS);
 
 	/* clear the context structure first */
 	memset(&rx_ctx, 0, sizeof(rx_ctx));
 
-	ring->rx_buf_len = vsi->rx_buf_len;
+	if (ring->vsi->type == I40E_VSI_MAIN)
+		xdp_rxq_info_unreg_mem_model(&ring->xdp_rxq);
+
+	ring->xsk_umem = i40e_xsk_umem(ring);
+	if (ring->xsk_umem) {
+		ring->rx_buf_len = ring->xsk_umem->chunk_size_nohr -
+				   XDP_PACKET_HEADROOM;
+		/* For AF_XDP ZC, we disallow packets to span on
+		 * multiple buffers, thus letting us skip that
+		 * handling in the fast-path.
+		 */
+		chain_len = 1;
+		ring->zca.free = i40e_zca_free;
+		ret = xdp_rxq_info_reg_mem_model(&ring->xdp_rxq,
+						 MEM_TYPE_ZERO_COPY,
+						 &ring->zca);
+		if (ret)
+			return ret;
+		dev_info(&vsi->back->pdev->dev,
+			 "Registered XDP mem model MEM_TYPE_ZERO_COPY on Rx ring %d\n",
+			 ring->queue_index);
+
+	} else {
+		ring->rx_buf_len = vsi->rx_buf_len;
+		if (ring->vsi->type == I40E_VSI_MAIN) {
+			ret = xdp_rxq_info_reg_mem_model(&ring->xdp_rxq,
+							 MEM_TYPE_PAGE_SHARED,
+							 NULL);
+			if (ret)
+				return ret;
+		}
+	}
 
 	rx_ctx.dbuff = DIV_ROUND_UP(ring->rx_buf_len,
 				    BIT_ULL(I40E_RXQ_CTX_DBUFF_SHIFT));
@@ -3243,7 +3278,15 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
 	ring->tail = hw->hw_addr + I40E_QRX_TAIL(pf_q);
 	writel(0, ring->tail);
 
-	i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring));
+	ok = ring->xsk_umem ?
+	     i40e_alloc_rx_buffers_zc(ring, I40E_DESC_UNUSED(ring)) :
+	     !i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring));
+	if (!ok) {
+		dev_info(&vsi->back->pdev->dev,
+			 "Failed allocate some buffers on %sRx ring %d (pf_q %d)\n",
+			 ring->xsk_umem ? "UMEM enabled " : "",
+			 ring->queue_index, pf_q);
+	}
 
 	return 0;
 }
@@ -12097,6 +12140,12 @@ static int i40e_xdp(struct net_device *dev,
 	case XDP_QUERY_PROG:
 		xdp->prog_id = vsi->xdp_prog ? vsi->xdp_prog->aux->id : 0;
 		return 0;
+	case XDP_QUERY_XSK_UMEM:
+		return i40e_xsk_umem_query(vsi, &xdp->xsk.umem,
+					   xdp->xsk.queue_id);
+	case XDP_SETUP_XSK_UMEM:
+		return i40e_xsk_umem_setup(vsi, xdp->xsk.umem,
+					   xdp->xsk.queue_id);
 	default:
 		return -EINVAL;
 	}
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 878fb4b47484..2c4d179ffebf 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -9,6 +9,7 @@
 #include "i40e_trace.h"
 #include "i40e_prototype.h"
 #include "i40e_txrx_common.h"
+#include "i40e_xsk.h"
 
 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
 				u32 td_tag)
@@ -1380,6 +1381,9 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
 		rx_ring->skb = NULL;
 	}
 
+	if (rx_ring->xsk_umem)
+		goto skip_free;
+
 	/* Free all the Rx ring sk_buffs */
 	for (i = 0; i < rx_ring->count; i++) {
 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
@@ -1408,6 +1412,7 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
 		rx_bi->page_offset = 0;
 	}
 
+skip_free:
 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
 	memset(rx_ring->rx_bi, 0, bi_size);
 
@@ -2641,7 +2646,9 @@ int i40e_napi_poll(struct napi_struct *napi, int budget)
 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
 
 	i40e_for_each_ring(ring, q_vector->rx) {
-		int cleaned = i40e_clean_rx_irq(ring, budget_per_ring);
+		int cleaned = ring->xsk_umem ?
+			      i40e_clean_rx_irq_zc(ring, budget_per_ring) :
+			      i40e_clean_rx_irq(ring, budget_per_ring);
 
 		work_done += cleaned;
 		/* if we clean as many as budgeted, we must not be done */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index bb04f6a731fe..100e92d2982f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -296,13 +296,17 @@ struct i40e_tx_buffer {
 
 struct i40e_rx_buffer {
 	dma_addr_t dma;
-	struct page *page;
-#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
-	__u32 page_offset;
-#else
-	__u16 page_offset;
-#endif
-	__u16 pagecnt_bias;
+	union {
+		struct {
+			struct page *page;
+			__u32 page_offset;
+			__u16 pagecnt_bias;
+		};
+		struct {
+			void *addr;
+			u64 handle;
+		};
+	};
 };
 
 struct i40e_queue_stats {
@@ -414,6 +418,8 @@ struct i40e_ring {
 
 	struct i40e_channel *ch;
 	struct xdp_rxq_info xdp_rxq;
+	struct xdp_umem *xsk_umem;
+	struct zero_copy_allocator zca; /* ZC allocator anchor */
 } ____cacheline_internodealigned_in_smp;
 
 static inline bool ring_uses_build_skb(struct i40e_ring *ring)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
new file mode 100644
index 000000000000..bf502f2307c2
--- /dev/null
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2018 Intel Corporation. */
+
+#include <linux/bpf_trace.h>
+#include <net/xdp_sock.h>
+#include <net/xdp.h>
+
+#include "i40e.h"
+#include "i40e_txrx_common.h"
+#include "i40e_xsk.h"
+
+/**
+ * i40e_alloc_xsk_umems - Allocate an array to store per ring UMEMs
+ * @vsi: Current VSI
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+static int i40e_alloc_xsk_umems(struct i40e_vsi *vsi)
+{
+	if (vsi->xsk_umems)
+		return 0;
+
+	vsi->num_xsk_umems_used = 0;
+	vsi->num_xsk_umems = vsi->alloc_queue_pairs;
+	vsi->xsk_umems = kcalloc(vsi->num_xsk_umems, sizeof(*vsi->xsk_umems),
+				 GFP_KERNEL);
+	if (!vsi->xsk_umems) {
+		vsi->num_xsk_umems = 0;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * i40e_add_xsk_umem - Store an UMEM for a certain ring/qid
+ * @vsi: Current VSI
+ * @umem: UMEM to store
+ * @qid: Ring/qid to associate with the UMEM
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+static int i40e_add_xsk_umem(struct i40e_vsi *vsi, struct xdp_umem *umem,
+			     u16 qid)
+{
+	int err;
+
+	err = i40e_alloc_xsk_umems(vsi);
+	if (err)
+		return err;
+
+	vsi->xsk_umems[qid] = umem;
+	vsi->num_xsk_umems_used++;
+
+	return 0;
+}
+
+/**
+ * i40e_remove_xsk_umem - Remove an UMEM for a certain ring/qid
+ * @vsi: Current VSI
+ * @qid: Ring/qid associated with the UMEM
+ **/
+static void i40e_remove_xsk_umem(struct i40e_vsi *vsi, u16 qid)
+{
+	vsi->xsk_umems[qid] = NULL;
+	vsi->num_xsk_umems_used--;
+
+	if (vsi->num_xsk_umems == 0) {
+		kfree(vsi->xsk_umems);
+		vsi->xsk_umems = NULL;
+		vsi->num_xsk_umems = 0;
+	}
+}
+
+/**
+ * i40e_xsk_umem_dma_map - DMA maps all UMEM memory for the netdev
+ * @vsi: Current VSI
+ * @umem: UMEM to DMA map
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+static int i40e_xsk_umem_dma_map(struct i40e_vsi *vsi, struct xdp_umem *umem)
+{
+	struct i40e_pf *pf = vsi->back;
+	struct device *dev;
+	unsigned int i, j;
+	dma_addr_t dma;
+
+	dev = &pf->pdev->dev;
+	for (i = 0; i < umem->npgs; i++) {
+		dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
+					 DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
+		if (dma_mapping_error(dev, dma))
+			goto out_unmap;
+
+		umem->pages[i].dma = dma;
+	}
+
+	return 0;
+
+out_unmap:
+	for (j = 0; j < i; j++) {
+		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
+				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
+		umem->pages[i].dma = 0;
+	}
+
+	return -1;
+}
+
+/**
+ * i40e_xsk_umem_dma_unmap - DMA unmaps all UMEM memory for the netdev
+ * @vsi: Current VSI
+ * @umem: UMEM to DMA map
+ **/
+static void i40e_xsk_umem_dma_unmap(struct i40e_vsi *vsi, struct xdp_umem *umem)
+{
+	struct i40e_pf *pf = vsi->back;
+	struct device *dev;
+	unsigned int i;
+
+	dev = &pf->pdev->dev;
+
+	for (i = 0; i < umem->npgs; i++) {
+		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
+				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
+
+		umem->pages[i].dma = 0;
+	}
+}
+
+/**
+ * i40e_xsk_umem_enable - Enable/associate an UMEM to a certain ring/qid
+ * @vsi: Current VSI
+ * @umem: UMEM
+ * @qid: Rx ring to associate UMEM to
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
+				u16 qid)
+{
+	bool if_running;
+	int err;
+
+	if (vsi->type != I40E_VSI_MAIN)
+		return -EINVAL;
+
+	if (qid >= vsi->num_queue_pairs)
+		return -EINVAL;
+
+	if (vsi->xsk_umems) {
+		if (qid >= vsi->num_xsk_umems)
+			return -EINVAL;
+		if (vsi->xsk_umems[qid])
+			return -EBUSY;
+	}
+
+	err = i40e_xsk_umem_dma_map(vsi, umem);
+	if (err)
+		return err;
+
+	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
+
+	if (if_running) {
+		err = i40e_queue_pair_disable(vsi, qid);
+		if (err)
+			return err;
+	}
+
+	err = i40e_add_xsk_umem(vsi, umem, qid);
+	if (err)
+		return err;
+
+	if (if_running) {
+		err = i40e_queue_pair_enable(vsi, qid);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+/**
+ * i40e_xsk_umem_disable - Diassociate an UMEM from a certain ring/qid
+ * @vsi: Current VSI
+ * @qid: Rx ring to associate UMEM to
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
+{
+	bool if_running;
+	int err;
+
+	if (!vsi->xsk_umems || qid >= vsi->num_xsk_umems ||
+	    !vsi->xsk_umems[qid])
+		return -EINVAL;
+
+	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
+
+	if (if_running) {
+		err = i40e_queue_pair_disable(vsi, qid);
+		if (err)
+			return err;
+	}
+
+	i40e_xsk_umem_dma_unmap(vsi, vsi->xsk_umems[qid]);
+	i40e_remove_xsk_umem(vsi, qid);
+
+	if (if_running) {
+		err = i40e_queue_pair_enable(vsi, qid);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+/**
+ * i40e_xsk_umem_query - Queries a certain ring/qid for its UMEM
+ * @vsi: Current VSI
+ * @umem: UMEM associated to the ring, if any
+ * @qid: Rx ring to associate UMEM to
+ *
+ * This function will store, if any, the UMEM associated to certain ring.
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+int i40e_xsk_umem_query(struct i40e_vsi *vsi, struct xdp_umem **umem,
+			u16 qid)
+{
+	if (vsi->type != I40E_VSI_MAIN)
+		return -EINVAL;
+
+	if (qid >= vsi->num_queue_pairs)
+		return -EINVAL;
+
+	if (vsi->xsk_umems) {
+		if (qid >= vsi->num_xsk_umems)
+			return -EINVAL;
+		*umem = vsi->xsk_umems[qid];
+		return 0;
+	}
+
+	*umem = NULL;
+	return 0;
+}
+
+/**
+ * i40e_xsk_umem_query - Queries a certain ring/qid for its UMEM
+ * @vsi: Current VSI
+ * @umem: UMEM to enable/associate to a ring, or NULL to disable
+ * @qid: Rx ring to (dis)associate UMEM (from)to
+ *
+ * This function enables or disables an UMEM to a certain ring.
+ *
+ * Returns 0 on success, <0 on failure
+ **/
+int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
+			u16 qid)
+{
+	return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
+		i40e_xsk_umem_disable(vsi, qid);
+}
+
+/**
+ * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
+ * @rx_ring: Rx ring
+ * @xdp: xdp_buff used as input to the XDP program
+ *
+ * This function enables or disables an UMEM to a certain ring.
+ *
+ * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
+ **/
+static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
+{
+	int err, result = I40E_XDP_PASS;
+	struct i40e_ring *xdp_ring;
+	struct bpf_prog *xdp_prog;
+	u32 act;
+
+	rcu_read_lock();
+	/* NB! xdp_prog will always be !NULL, due to the fact that
+	 * this path is enabled by setting an XDP program.
+	 */
+	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
+	act = bpf_prog_run_xdp(xdp_prog, xdp);
+	xdp->handle += xdp->data - xdp->data_hard_start;
+	switch (act) {
+	case XDP_PASS:
+		break;
+	case XDP_TX:
+		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
+		result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
+		break;
+	case XDP_REDIRECT:
+		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
+		result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
+		break;
+	default:
+		bpf_warn_invalid_xdp_action(act);
+	case XDP_ABORTED:
+		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
+		/* fallthrough -- handle aborts by dropping packet */
+	case XDP_DROP:
+		result = I40E_XDP_CONSUMED;
+		break;
+	}
+	rcu_read_unlock();
+	return result;
+}
+
+/**
+ * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
+ * @rx_ring: Rx ring
+ * @bi: Rx buffer to populate
+ *
+ * This function allocates an Rx buffer. The buffer can come from fill
+ * queue, or via the recycle queue (next_to_alloc).
+ *
+ * Returns true for a successful allocation, false otherwise
+ **/
+static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
+				 struct i40e_rx_buffer *bi)
+{
+	struct xdp_umem *umem = rx_ring->xsk_umem;
+	void *addr = bi->addr;
+	u64 handle, hr;
+
+	if (addr) {
+		rx_ring->rx_stats.page_reuse_count++;
+		return true;
+	}
+
+	if (!xsk_umem_peek_addr(umem, &handle)) {
+		rx_ring->rx_stats.alloc_page_failed++;
+		return false;
+	}
+
+	hr = umem->headroom + XDP_PACKET_HEADROOM;
+
+	bi->dma = xdp_umem_get_dma(umem, handle);
+	bi->dma += hr;
+
+	bi->addr = xdp_umem_get_data(umem, handle);
+	bi->addr += hr;
+
+	bi->handle = handle + umem->headroom;
+
+	xsk_umem_discard_addr(umem);
+	return true;
+}
+
+/**
+ * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
+ * @rx_ring: Rx ring
+ * @count: The number of buffers to allocate
+ *
+ * This function allocates a number of Rx buffers and places them on
+ * the Rx ring.
+ *
+ * Returns true for a successful allocation, false otherwise
+ **/
+bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
+{
+	u16 ntu = rx_ring->next_to_use;
+	union i40e_rx_desc *rx_desc;
+	struct i40e_rx_buffer *bi;
+	bool ok = true;
+
+	rx_desc = I40E_RX_DESC(rx_ring, ntu);
+	bi = &rx_ring->rx_bi[ntu];
+	do {
+		if (!i40e_alloc_buffer_zc(rx_ring, bi)) {
+			ok = false;
+			goto no_buffers;
+		}
+
+		dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
+						 rx_ring->rx_buf_len,
+						 DMA_BIDIRECTIONAL);
+
+		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
+
+		rx_desc++;
+		bi++;
+		ntu++;
+
+		if (unlikely(ntu == rx_ring->count)) {
+			rx_desc = I40E_RX_DESC(rx_ring, 0);
+			bi = rx_ring->rx_bi;
+			ntu = 0;
+		}
+
+		rx_desc->wb.qword1.status_error_len = 0;
+		count--;
+	} while (count);
+
+no_buffers:
+	if (rx_ring->next_to_use != ntu)
+		i40e_release_rx_desc(rx_ring, ntu);
+
+	return ok;
+}
+
+/**
+ * i40e_get_rx_buffer_zc - Return the current Rx buffer
+ * @rx_ring: Rx ring
+ * @size: The size of the rx buffer (read from descriptor)
+ *
+ * This function returns the current, received Rx buffer, and also
+ * does DMA synchronization.  the Rx ring.
+ *
+ * Returns the received Rx buffer
+ **/
+static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
+						    const unsigned int size)
+{
+	struct i40e_rx_buffer *bi;
+
+	bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
+
+	/* we are reusing so sync this buffer for CPU use */
+	dma_sync_single_range_for_cpu(rx_ring->dev,
+				      bi->dma, 0,
+				      size,
+				      DMA_BIDIRECTIONAL);
+
+	return bi;
+}
+
+/**
+ * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
+ * @rx_ring: Rx ring
+ * @old_bi: The Rx buffer to recycle
+ *
+ * This function recycles a finished Rx buffer, and places it on the
+ * recycle queue (next_to_alloc).
+ **/
+static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
+				    struct i40e_rx_buffer *old_bi)
+{
+	struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
+	unsigned long mask = (unsigned long)rx_ring->xsk_umem->props.chunk_mask;
+	u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
+	u16 nta = rx_ring->next_to_alloc;
+
+	/* update, and store next to alloc */
+	nta++;
+	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
+
+	/* transfer page from old buffer to new buffer */
+	new_bi->dma = old_bi->dma & mask;
+	new_bi->dma += hr;
+
+	new_bi->addr = (void *)((unsigned long)old_bi->addr & mask);
+	new_bi->addr += hr;
+
+	new_bi->handle = old_bi->handle & mask;
+	new_bi->handle += rx_ring->xsk_umem->headroom;
+
+	old_bi->addr = NULL;
+}
+
+/**
+ * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
+ * @alloc: Zero-copy allocator
+ * @handle: Buffer handle
+ **/
+void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
+{
+	struct i40e_rx_buffer *bi;
+	struct i40e_ring *rx_ring;
+	u64 hr, mask;
+	u16 nta;
+
+	rx_ring = container_of(alloc, struct i40e_ring, zca);
+	hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
+	mask = rx_ring->xsk_umem->props.chunk_mask;
+
+	nta = rx_ring->next_to_alloc;
+	bi = &rx_ring->rx_bi[nta];
+
+	nta++;
+	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
+
+	handle &= mask;
+
+	bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
+	bi->dma += hr;
+
+	bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
+	bi->addr += hr;
+
+	bi->handle = (u64)handle + rx_ring->xsk_umem->headroom;
+}
+
+/**
+ * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
+ * @rx_ring: Rx ring
+ * @bi: Rx buffer
+ * @xdp: xdp_buff
+ *
+ * This functions allocates a new skb from a zero-copy Rx buffer.
+ *
+ * Returns the skb, or NULL on failure.
+ **/
+static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
+					     struct i40e_rx_buffer *bi,
+					     struct xdp_buff *xdp)
+{
+	unsigned int metasize = xdp->data - xdp->data_meta;
+	unsigned int datasize = xdp->data_end - xdp->data;
+	struct sk_buff *skb;
+
+	/* allocate a skb to store the frags */
+	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
+			       xdp->data_end - xdp->data_hard_start,
+			       GFP_ATOMIC | __GFP_NOWARN);
+	if (unlikely(!skb))
+		return NULL;
+
+	skb_reserve(skb, xdp->data - xdp->data_hard_start);
+	memcpy(__skb_put(skb, datasize), xdp->data, datasize);
+	if (metasize)
+		skb_metadata_set(skb, metasize);
+
+	i40e_reuse_rx_buffer_zc(rx_ring, bi);
+	return skb;
+}
+
+/**
+ * i40e_inc_ntc: Advance the next_to_clean index
+ * @rx_ring: Rx ring
+ **/
+static void i40e_inc_ntc(struct i40e_ring *rx_ring)
+{
+	u32 ntc = rx_ring->next_to_clean + 1;
+
+	ntc = (ntc < rx_ring->count) ? ntc : 0;
+	rx_ring->next_to_clean = ntc;
+	prefetch(I40E_RX_DESC(rx_ring, ntc));
+}
+
+/**
+ * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
+ * @rx_ring: Rx ring
+ * @budget: NAPI budget
+ *
+ * Returns amount of work completed
+ **/
+int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
+{
+	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
+	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
+	unsigned int xdp_res, xdp_xmit = 0;
+	bool failure = false;
+	struct sk_buff *skb;
+	struct xdp_buff xdp;
+
+	xdp.rxq = &rx_ring->xdp_rxq;
+
+	while (likely(total_rx_packets < (unsigned int)budget)) {
+		struct i40e_rx_buffer *bi;
+		union i40e_rx_desc *rx_desc;
+		unsigned int size;
+		u16 vlan_tag;
+		u8 rx_ptype;
+		u64 qword;
+
+		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
+			failure = failure ||
+				  !i40e_alloc_rx_buffers_zc(rx_ring,
+							    cleaned_count);
+			cleaned_count = 0;
+		}
+
+		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
+		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+
+		/* This memory barrier is needed to keep us from reading
+		 * any other fields out of the rx_desc until we have
+		 * verified the descriptor has been written back.
+		 */
+		dma_rmb();
+
+		bi = i40e_clean_programming_status(rx_ring, rx_desc,
+						   qword);
+		if (unlikely(bi)) {
+			i40e_reuse_rx_buffer_zc(rx_ring, bi);
+			cleaned_count++;
+			continue;
+		}
+
+		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
+		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
+		if (!size)
+			break;
+
+		bi = i40e_get_rx_buffer_zc(rx_ring, size);
+		xdp.data = bi->addr;
+		xdp.data_meta = xdp.data;
+		xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
+		xdp.data_end = xdp.data + size;
+		xdp.handle = bi->handle;
+
+		xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
+		if (xdp_res) {
+			if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
+				xdp_xmit |= xdp_res;
+				bi->addr = NULL;
+			} else {
+				i40e_reuse_rx_buffer_zc(rx_ring, bi);
+			}
+
+			total_rx_bytes += size;
+			total_rx_packets++;
+
+			cleaned_count++;
+			i40e_inc_ntc(rx_ring);
+			continue;
+		}
+
+		/* XDP_PASS path */
+
+		/* NB! We are not checking for errors using
+		 * i40e_test_staterr with
+		 * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
+		 * SBP is *not* set in PRT_SBPVSI (default not set).
+		 */
+		skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
+		if (!skb) {
+			rx_ring->rx_stats.alloc_buff_failed++;
+			break;
+		}
+
+		cleaned_count++;
+		i40e_inc_ntc(rx_ring);
+
+		if (eth_skb_pad(skb))
+			continue;
+
+		total_rx_bytes += skb->len;
+		total_rx_packets++;
+
+		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
+			   I40E_RXD_QW1_PTYPE_SHIFT;
+		i40e_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
+
+		vlan_tag = (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) ?
+			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;
+		i40e_receive_skb(rx_ring, skb, vlan_tag);
+	}
+
+	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
+	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
+	return failure ? budget : (int)total_rx_packets;
+}
+
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.h b/drivers/net/ethernet/intel/i40e/i40e_xsk.h
new file mode 100644
index 000000000000..427a844f78a7
--- /dev/null
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright(c) 2018 Intel Corporation. */
+
+#ifndef _I40E_XSK_H_
+#define _I40E_XSK_H_
+
+struct i40e_vsi;
+struct xdp_umem;
+struct zero_copy_allocator;
+
+int i40e_queue_pair_disable(struct i40e_vsi *vsi, int queue_pair);
+int i40e_queue_pair_enable(struct i40e_vsi *vsi, int queue_pair);
+int i40e_xsk_umem_query(struct i40e_vsi *vsi, struct xdp_umem **umem,
+			u16 qid);
+int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
+			u16 qid);
+void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle);
+bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 cleaned_count);
+int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget);
+
+#endif /* _I40E_XSK_H_ */
-- 
cgit v1.2.3-59-g8ed1b


From a96e7472732842d76af0132c5f87f531f312d7a9 Mon Sep 17 00:00:00 2001
From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Tue, 28 Aug 2018 14:44:33 +0200
Subject: i40e: move common Tx functions to i40e_txrx_common.h

This patch prepares for the upcoming zero-copy Tx functionality, by
moving common functions and refactor chunks of code into re-usable
functions, used both by the regular path and zero-copy path.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_txrx.c        | 35 +------------
 drivers/net/ethernet/intel/i40e/i40e_txrx_common.h | 59 ++++++++++++++++++++++
 2 files changed, 61 insertions(+), 33 deletions(-)

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 2c4d179ffebf..11e201fcb57a 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -11,16 +11,6 @@
 #include "i40e_txrx_common.h"
 #include "i40e_xsk.h"
 
-static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
-				u32 td_tag)
-{
-	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
-			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
-			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
-			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
-			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
-}
-
 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
 /**
  * i40e_fdir - Generate a Flow Director descriptor based on fdata
@@ -769,8 +759,6 @@ void i40e_detect_recover_hung(struct i40e_vsi *vsi)
 	}
 }
 
-#define WB_STRIDE 4
-
 /**
  * i40e_clean_tx_irq - Reclaim resources after transmit completes
  * @vsi: the VSI we care about
@@ -875,27 +863,8 @@ static bool i40e_clean_tx_irq(struct i40e_vsi *vsi,
 
 	i += tx_ring->count;
 	tx_ring->next_to_clean = i;
-	u64_stats_update_begin(&tx_ring->syncp);
-	tx_ring->stats.bytes += total_bytes;
-	tx_ring->stats.packets += total_packets;
-	u64_stats_update_end(&tx_ring->syncp);
-	tx_ring->q_vector->tx.total_bytes += total_bytes;
-	tx_ring->q_vector->tx.total_packets += total_packets;
-
-	if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
-		/* check to see if there are < 4 descriptors
-		 * waiting to be written back, then kick the hardware to force
-		 * them to be written back in case we stay in NAPI.
-		 * In this mode on X722 we do not enable Interrupt.
-		 */
-		unsigned int j = i40e_get_tx_pending(tx_ring, false);
-
-		if (budget &&
-		    ((j / WB_STRIDE) == 0) && (j > 0) &&
-		    !test_bit(__I40E_VSI_DOWN, vsi->state) &&
-		    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
-			tx_ring->arm_wb = true;
-	}
+	i40e_update_tx_stats(tx_ring, total_packets, total_bytes);
+	i40e_arm_wb(tx_ring, vsi, budget);
 
 	if (ring_is_xdp(tx_ring))
 		return !!budget;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
index 2bd5187fcd66..b5afd479a9c5 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
@@ -28,4 +28,63 @@ void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val);
 #define I40E_XDP_TX		BIT(1)
 #define I40E_XDP_REDIR		BIT(2)
 
+/**
+ * build_ctob - Builds the Tx descriptor (cmd, offset and type) qword
+ **/
+static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
+				u32 td_tag)
+{
+	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
+			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
+			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
+			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
+			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
+}
+
+/**
+ * i40e_update_tx_stats - Update the egress statistics for the Tx ring
+ * @tx_ring: Tx ring to update
+ * @total_packet: total packets sent
+ * @total_bytes: total bytes sent
+ **/
+static inline void i40e_update_tx_stats(struct i40e_ring *tx_ring,
+					unsigned int total_packets,
+					unsigned int total_bytes)
+{
+	u64_stats_update_begin(&tx_ring->syncp);
+	tx_ring->stats.bytes += total_bytes;
+	tx_ring->stats.packets += total_packets;
+	u64_stats_update_end(&tx_ring->syncp);
+	tx_ring->q_vector->tx.total_bytes += total_bytes;
+	tx_ring->q_vector->tx.total_packets += total_packets;
+}
+
+#define WB_STRIDE 4
+
+/**
+ * i40e_arm_wb - (Possibly) arms Tx write-back
+ * @tx_ring: Tx ring to update
+ * @vsi: the VSI
+ * @budget: the NAPI budget left
+ **/
+static inline void i40e_arm_wb(struct i40e_ring *tx_ring,
+			       struct i40e_vsi *vsi,
+			       int budget)
+{
+	if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
+		/* check to see if there are < 4 descriptors
+		 * waiting to be written back, then kick the hardware to force
+		 * them to be written back in case we stay in NAPI.
+		 * In this mode on X722 we do not enable Interrupt.
+		 */
+		unsigned int j = i40e_get_tx_pending(tx_ring, false);
+
+		if (budget &&
+		    ((j / WB_STRIDE) == 0) && j > 0 &&
+		    !test_bit(__I40E_VSI_DOWN, vsi->state) &&
+		    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
+			tx_ring->arm_wb = true;
+	}
+}
+
 #endif /* I40E_TXRX_COMMON_ */
-- 
cgit v1.2.3-59-g8ed1b


From 1328dcddbd53900481994f4c4d8b79e64477965e Mon Sep 17 00:00:00 2001
From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Tue, 28 Aug 2018 14:44:34 +0200
Subject: i40e: add AF_XDP zero-copy Tx support

This patch adds zero-copy Tx support for AF_XDP sockets. It implements
the ndo_xsk_async_xmit netdev ndo and performs all the Tx logic from a
NAPI context. This means pulling egress packets from the Tx ring,
placing the frames on the NIC HW descriptor ring and completing sent
frames back to the application via the completion ring.

The regular XDP Tx ring is used for AF_XDP as well. This rationale for
this is as follows: XDP_REDIRECT guarantees mutual exclusion between
different NAPI contexts based on CPU id. In other words, a netdev can
XDP_REDIRECT to another netdev with a different NAPI context, since
the operation is bound to a specific core and each core has its own
hardware ring.

As the AF_XDP Tx action is running in the same NAPI context and using
the same ring, it will also be protected from XDP_REDIRECT actions
with the exact same mechanism.

As with AF_XDP Rx, all AF_XDP Tx specific functions are added to
i40e_xsk.c.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c |   4 +
 drivers/net/ethernet/intel/i40e/i40e_txrx.c |   6 +-
 drivers/net/ethernet/intel/i40e/i40e_xsk.c  | 173 ++++++++++++++++++++++++++++
 drivers/net/ethernet/intel/i40e/i40e_xsk.h  |   4 +
 4 files changed, 186 insertions(+), 1 deletion(-)

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 848eea7c84db..5da7eb0fe4ae 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -3074,6 +3074,9 @@ static int i40e_configure_tx_ring(struct i40e_ring *ring)
 	i40e_status err = 0;
 	u32 qtx_ctl = 0;
 
+	if (ring_is_xdp(ring))
+		ring->xsk_umem = i40e_xsk_umem(ring);
+
 	/* some ATR related tx ring init */
 	if (vsi->back->flags & I40E_FLAG_FD_ATR_ENABLED) {
 		ring->atr_sample_rate = vsi->back->atr_sample_rate;
@@ -12185,6 +12188,7 @@ static const struct net_device_ops i40e_netdev_ops = {
 	.ndo_bridge_setlink	= i40e_ndo_bridge_setlink,
 	.ndo_bpf		= i40e_xdp,
 	.ndo_xdp_xmit		= i40e_xdp_xmit,
+	.ndo_xsk_async_xmit	= i40e_xsk_async_xmit,
 };
 
 /**
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 11e201fcb57a..37bd4e50ccde 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2597,7 +2597,11 @@ int i40e_napi_poll(struct napi_struct *napi, int budget)
 	 * budget and be more aggressive about cleaning up the Tx descriptors.
 	 */
 	i40e_for_each_ring(ring, q_vector->tx) {
-		if (!i40e_clean_tx_irq(vsi, ring, budget)) {
+		bool wd = ring->xsk_umem ?
+			  i40e_clean_xdp_tx_irq(vsi, ring, budget) :
+			  i40e_clean_tx_irq(vsi, ring, budget);
+
+		if (!wd) {
 			clean_complete = false;
 			continue;
 		}
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index bf502f2307c2..94947a826bc3 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -659,3 +659,176 @@ int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
 	return failure ? budget : (int)total_rx_packets;
 }
 
+/**
+ * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
+ * @xdp_ring: XDP Tx ring
+ * @budget: NAPI budget
+ *
+ * Returns true if the work is finished.
+ **/
+static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
+{
+	unsigned int total_packets = 0;
+	struct i40e_tx_buffer *tx_bi;
+	struct i40e_tx_desc *tx_desc;
+	bool work_done = true;
+	dma_addr_t dma;
+	u32 len;
+
+	while (budget-- > 0) {
+		if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
+			xdp_ring->tx_stats.tx_busy++;
+			work_done = false;
+			break;
+		}
+
+		if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &dma, &len))
+			break;
+
+		dma_sync_single_for_device(xdp_ring->dev, dma, len,
+					   DMA_BIDIRECTIONAL);
+
+		tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
+		tx_bi->bytecount = len;
+
+		tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
+		tx_desc->buffer_addr = cpu_to_le64(dma);
+		tx_desc->cmd_type_offset_bsz =
+			build_ctob(I40E_TX_DESC_CMD_ICRC
+				   | I40E_TX_DESC_CMD_EOP,
+				   0, len, 0);
+		total_packets++;
+
+		xdp_ring->next_to_use++;
+		if (xdp_ring->next_to_use == xdp_ring->count)
+			xdp_ring->next_to_use = 0;
+	}
+
+	if (total_packets > 0) {
+		/* Request an interrupt for the last frame and bump tail ptr. */
+		tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
+						 I40E_TXD_QW1_CMD_SHIFT);
+		i40e_xdp_ring_update_tail(xdp_ring);
+
+		xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
+	}
+
+	return !!budget && work_done;
+}
+
+/**
+ * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
+ * @tx_ring: XDP Tx ring
+ * @tx_bi: Tx buffer info to clean
+ **/
+static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
+				     struct i40e_tx_buffer *tx_bi)
+{
+	xdp_return_frame(tx_bi->xdpf);
+	dma_unmap_single(tx_ring->dev,
+			 dma_unmap_addr(tx_bi, dma),
+			 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
+	dma_unmap_len_set(tx_bi, len, 0);
+}
+
+/**
+ * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
+ * @tx_ring: XDP Tx ring
+ * @tx_bi: Tx buffer info to clean
+ *
+ * Returns true if cleanup/tranmission is done.
+ **/
+bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
+			   struct i40e_ring *tx_ring, int napi_budget)
+{
+	unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
+	u32 i, completed_frames, frames_ready, xsk_frames = 0;
+	struct xdp_umem *umem = tx_ring->xsk_umem;
+	u32 head_idx = i40e_get_head(tx_ring);
+	bool work_done = true, xmit_done;
+	struct i40e_tx_buffer *tx_bi;
+
+	if (head_idx < tx_ring->next_to_clean)
+		head_idx += tx_ring->count;
+	frames_ready = head_idx - tx_ring->next_to_clean;
+
+	if (frames_ready == 0) {
+		goto out_xmit;
+	} else if (frames_ready > budget) {
+		completed_frames = budget;
+		work_done = false;
+	} else {
+		completed_frames = frames_ready;
+	}
+
+	ntc = tx_ring->next_to_clean;
+
+	for (i = 0; i < completed_frames; i++) {
+		tx_bi = &tx_ring->tx_bi[ntc];
+
+		if (tx_bi->xdpf)
+			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
+		else
+			xsk_frames++;
+
+		tx_bi->xdpf = NULL;
+		total_bytes += tx_bi->bytecount;
+
+		if (++ntc >= tx_ring->count)
+			ntc = 0;
+	}
+
+	tx_ring->next_to_clean += completed_frames;
+	if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
+		tx_ring->next_to_clean -= tx_ring->count;
+
+	if (xsk_frames)
+		xsk_umem_complete_tx(umem, xsk_frames);
+
+	i40e_arm_wb(tx_ring, vsi, budget);
+	i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
+
+out_xmit:
+	xmit_done = i40e_xmit_zc(tx_ring, budget);
+
+	return work_done && xmit_done;
+}
+
+/**
+ * i40e_xsk_async_xmit - Implements the ndo_xsk_async_xmit
+ * @dev: the netdevice
+ * @queue_id: queue id to wake up
+ *
+ * Returns <0 for errors, 0 otherwise.
+ **/
+int i40e_xsk_async_xmit(struct net_device *dev, u32 queue_id)
+{
+	struct i40e_netdev_priv *np = netdev_priv(dev);
+	struct i40e_vsi *vsi = np->vsi;
+	struct i40e_ring *ring;
+
+	if (test_bit(__I40E_VSI_DOWN, vsi->state))
+		return -ENETDOWN;
+
+	if (!i40e_enabled_xdp_vsi(vsi))
+		return -ENXIO;
+
+	if (queue_id >= vsi->num_queue_pairs)
+		return -ENXIO;
+
+	if (!vsi->xdp_rings[queue_id]->xsk_umem)
+		return -ENXIO;
+
+	ring = vsi->xdp_rings[queue_id];
+
+	/* The idea here is that if NAPI is running, mark a miss, so
+	 * it will run again. If not, trigger an interrupt and
+	 * schedule the NAPI from interrupt context. If NAPI would be
+	 * scheduled here, the interrupt affinity would not be
+	 * honored.
+	 */
+	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
+		i40e_force_wb(vsi, ring->q_vector);
+
+	return 0;
+}
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.h b/drivers/net/ethernet/intel/i40e/i40e_xsk.h
index 427a844f78a7..9038c5d5cf08 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.h
@@ -18,4 +18,8 @@ void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle);
 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 cleaned_count);
 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget);
 
+bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
+			   struct i40e_ring *tx_ring, int napi_budget);
+int i40e_xsk_async_xmit(struct net_device *dev, u32 queue_id);
+
 #endif /* _I40E_XSK_H_ */
-- 
cgit v1.2.3-59-g8ed1b


From cf484f9f91f702e61eb47f7b142de6edc33a4a88 Mon Sep 17 00:00:00 2001
From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Fri, 31 Aug 2018 13:40:01 +0200
Subject: i40e: fix possible compiler warning in xsk TX path

With certain gcc versions, it was possible to get the warning
"'tx_desc' may be used uninitialized in this function" for the
i40e_xmit_zc. This was not possible, however this commit simplifies
the code path so that this warning is no longer emitted.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
 drivers/net/ethernet/intel/i40e/i40e_xsk.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index 94947a826bc3..41ca7e1310bc 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -668,9 +668,8 @@ int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
  **/
 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 {
-	unsigned int total_packets = 0;
+	struct i40e_tx_desc *tx_desc = NULL;
 	struct i40e_tx_buffer *tx_bi;
-	struct i40e_tx_desc *tx_desc;
 	bool work_done = true;
 	dma_addr_t dma;
 	u32 len;
@@ -697,14 +696,13 @@ static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
 			build_ctob(I40E_TX_DESC_CMD_ICRC
 				   | I40E_TX_DESC_CMD_EOP,
 				   0, len, 0);
-		total_packets++;
 
 		xdp_ring->next_to_use++;
 		if (xdp_ring->next_to_use == xdp_ring->count)
 			xdp_ring->next_to_use = 0;
 	}
 
-	if (total_packets > 0) {
+	if (tx_desc) {
 		/* Request an interrupt for the last frame and bump tail ptr. */
 		tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
 						 I40E_TXD_QW1_CMD_SHIFT);
-- 
cgit v1.2.3-59-g8ed1b


From 93ee30f3e8b412c5fc2d2f7d9d002529d9a209ad Mon Sep 17 00:00:00 2001
From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Fri, 31 Aug 2018 13:40:02 +0200
Subject: xsk: i40e: get rid of useless struct xdp_umem_props

This commit gets rid of the structure xdp_umem_props. It was there to
be able to break a dependency at one point, but this is no longer
needed. The values in the struct are instead stored directly in the
xdp_umem structure. This simplifies the xsk code as well as af_xdp
zero-copy drivers and as a bonus gets rid of one internal header file.

The i40e driver is also adapted to the new interface in this commit.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
 drivers/net/ethernet/intel/i40e/i40e_xsk.c |  4 ++--
 include/net/xdp_sock.h                     |  8 ++------
 net/xdp/xdp_umem.c                         |  4 ++--
 net/xdp/xdp_umem_props.h                   | 14 --------------
 net/xdp/xsk.c                              | 10 ++++++----
 net/xdp/xsk_queue.c                        |  5 +++--
 net/xdp/xsk_queue.h                        | 13 +++++++------
 7 files changed, 22 insertions(+), 36 deletions(-)
 delete mode 100644 net/xdp/xdp_umem_props.h

(limited to 'drivers/net/ethernet/intel/i40e')

diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index 41ca7e1310bc..2ebfc78bbd09 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -442,7 +442,7 @@ static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
 				    struct i40e_rx_buffer *old_bi)
 {
 	struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
-	unsigned long mask = (unsigned long)rx_ring->xsk_umem->props.chunk_mask;
+	unsigned long mask = (unsigned long)rx_ring->xsk_umem->chunk_mask;
 	u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
 	u16 nta = rx_ring->next_to_alloc;
 
@@ -477,7 +477,7 @@ void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
 
 	rx_ring = container_of(alloc, struct i40e_ring, zca);
 	hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
-	mask = rx_ring->xsk_umem->props.chunk_mask;
+	mask = rx_ring->xsk_umem->chunk_mask;
 
 	nta = rx_ring->next_to_alloc;
 	bi = &rx_ring->rx_bi[nta];
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index 56994ad1ab40..932ca0dad6f3 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -16,11 +16,6 @@
 struct net_device;
 struct xsk_queue;
 
-struct xdp_umem_props {
-	u64 chunk_mask;
-	u64 size;
-};
-
 struct xdp_umem_page {
 	void *addr;
 	dma_addr_t dma;
@@ -30,7 +25,8 @@ struct xdp_umem {
 	struct xsk_queue *fq;
 	struct xsk_queue *cq;
 	struct xdp_umem_page *pages;
-	struct xdp_umem_props props;
+	u64 chunk_mask;
+	u64 size;
 	u32 headroom;
 	u32 chunk_size_nohr;
 	struct user_struct *user;
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index d179732617dc..b3b632c5aeae 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -312,8 +312,8 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr)
 
 	umem->pid = get_task_pid(current, PIDTYPE_PID);
 	umem->address = (unsigned long)addr;
-	umem->props.chunk_mask = ~((u64)chunk_size - 1);
-	umem->props.size = size;
+	umem->chunk_mask = ~((u64)chunk_size - 1);
+	umem->size = size;
 	umem->headroom = headroom;
 	umem->chunk_size_nohr = chunk_size - headroom;
 	umem->npgs = size / PAGE_SIZE;
diff --git a/net/xdp/xdp_umem_props.h b/net/xdp/xdp_umem_props.h
deleted file mode 100644
index 40eab10dfc49..000000000000
--- a/net/xdp/xdp_umem_props.h
+++ /dev/null
@@ -1,14 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/* XDP user-space packet buffer
- * Copyright(c) 2018 Intel Corporation.
- */
-
-#ifndef XDP_UMEM_PROPS_H_
-#define XDP_UMEM_PROPS_H_
-
-struct xdp_umem_props {
-	u64 chunk_mask;
-	u64 size;
-};
-
-#endif /* XDP_UMEM_PROPS_H_ */
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 569048e299df..5a432dfee4ee 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -470,8 +470,10 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 		goto out_unlock;
 	} else {
 		/* This xsk has its own umem. */
-		xskq_set_umem(xs->umem->fq, &xs->umem->props);
-		xskq_set_umem(xs->umem->cq, &xs->umem->props);
+		xskq_set_umem(xs->umem->fq, xs->umem->size,
+			      xs->umem->chunk_mask);
+		xskq_set_umem(xs->umem->cq, xs->umem->size,
+			      xs->umem->chunk_mask);
 
 		err = xdp_umem_assign_dev(xs->umem, dev, qid, flags);
 		if (err)
@@ -481,8 +483,8 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 	xs->dev = dev;
 	xs->zc = xs->umem->zc;
 	xs->queue_id = qid;
-	xskq_set_umem(xs->rx, &xs->umem->props);
-	xskq_set_umem(xs->tx, &xs->umem->props);
+	xskq_set_umem(xs->rx, xs->umem->size, xs->umem->chunk_mask);
+	xskq_set_umem(xs->tx, xs->umem->size, xs->umem->chunk_mask);
 	xdp_add_sk_umem(xs->umem, xs);
 
 out_unlock:
diff --git a/net/xdp/xsk_queue.c b/net/xdp/xsk_queue.c
index 6c32e92e98fc..2dc1384d9f27 100644
--- a/net/xdp/xsk_queue.c
+++ b/net/xdp/xsk_queue.c
@@ -7,12 +7,13 @@
 
 #include "xsk_queue.h"
 
-void xskq_set_umem(struct xsk_queue *q, struct xdp_umem_props *umem_props)
+void xskq_set_umem(struct xsk_queue *q, u64 size, u64 chunk_mask)
 {
 	if (!q)
 		return;
 
-	q->umem_props = *umem_props;
+	q->size = size;
+	q->chunk_mask = chunk_mask;
 }
 
 static u32 xskq_umem_get_ring_size(struct xsk_queue *q)
diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h
index 8a64b150be54..82252cccb4e0 100644
--- a/net/xdp/xsk_queue.h
+++ b/net/xdp/xsk_queue.h
@@ -31,7 +31,8 @@ struct xdp_umem_ring {
 };
 
 struct xsk_queue {
-	struct xdp_umem_props umem_props;
+	u64 chunk_mask;
+	u64 size;
 	u32 ring_mask;
 	u32 nentries;
 	u32 prod_head;
@@ -78,7 +79,7 @@ static inline u32 xskq_nb_free(struct xsk_queue *q, u32 producer, u32 dcnt)
 
 static inline bool xskq_is_valid_addr(struct xsk_queue *q, u64 addr)
 {
-	if (addr >= q->umem_props.size) {
+	if (addr >= q->size) {
 		q->invalid_descs++;
 		return false;
 	}
@@ -92,7 +93,7 @@ static inline u64 *xskq_validate_addr(struct xsk_queue *q, u64 *addr)
 		struct xdp_umem_ring *ring = (struct xdp_umem_ring *)q->ring;
 		unsigned int idx = q->cons_tail & q->ring_mask;
 
-		*addr = READ_ONCE(ring->desc[idx]) & q->umem_props.chunk_mask;
+		*addr = READ_ONCE(ring->desc[idx]) & q->chunk_mask;
 		if (xskq_is_valid_addr(q, *addr))
 			return addr;
 
@@ -173,8 +174,8 @@ static inline bool xskq_is_valid_desc(struct xsk_queue *q, struct xdp_desc *d)
 	if (!xskq_is_valid_addr(q, d->addr))
 		return false;
 
-	if (((d->addr + d->len) & q->umem_props.chunk_mask) !=
-	    (d->addr & q->umem_props.chunk_mask)) {
+	if (((d->addr + d->len) & q->chunk_mask) !=
+	    (d->addr & q->chunk_mask)) {
 		q->invalid_descs++;
 		return false;
 	}
@@ -253,7 +254,7 @@ static inline bool xskq_empty_desc(struct xsk_queue *q)
 	return xskq_nb_free(q, q->prod_tail, q->nentries) == q->nentries;
 }
 
-void xskq_set_umem(struct xsk_queue *q, struct xdp_umem_props *umem_props);
+void xskq_set_umem(struct xsk_queue *q, u64 size, u64 chunk_mask);
 struct xsk_queue *xskq_create(u32 nentries, bool umem_queue);
 void xskq_destroy(struct xsk_queue *q_ops);
 
-- 
cgit v1.2.3-59-g8ed1b