[dpdk-dev] [PATCH v2 5/7] ethdev: add mtu accessors

[David Marchand <david.marchand@6wind.com>]

From: Samuel Gauthier <samuel.gauthier@6wind.com>

This patch adds two new functions in ethdev api to retrieve current MTU and
change MTU of a port.
Only .mtu_set function is pmd specific.
pmd should update its max_rx_pkt_len if needed.

This operation has been implemented for rte_em_pmd, rte_igb_pmd and
rte_ixgbe_pmd.

Signed-off-by: Samuel Gauthier <samuel.gauthier@6wind.com>
Signed-off-by: Ivan Boule <ivan.boule@6wind.com>
Signed-off-by: David Marchand <david.marchand@6wind.com>
---
 lib/librte_ether/rte_ethdev.c       |   41 +++++++++++++++++++++++++--
 lib/librte_ether/rte_ethdev.h       |   34 +++++++++++++++++++++-
 lib/librte_pmd_e1000/em_ethdev.c    |   42 +++++++++++++++++++++++++++
 lib/librte_pmd_e1000/igb_ethdev.c   |   53 +++++++++++++++++++++++++++++++++++
 lib/librte_pmd_ixgbe/ixgbe_ethdev.c |   49 ++++++++++++++++++++++++++++++++
 lib/librte_pmd_ixgbe/ixgbe_rxtx.c   |    2 +-
 6 files changed, 217 insertions(+), 4 deletions(-)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index df18b7b..a411f99 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -200,9 +200,9 @@ rte_eth_dev_init(struct rte_pci_driver *pci_drv,
 	TAILQ_INIT(&(eth_dev->callbacks));
 
 	/*
-	 * Set the default maximum frame size.
+	 * Set the default MTU.
 	 */
-	eth_dev->data->max_frame_size = ETHER_MAX_LEN;
+	eth_dev->data->mtu = ETHER_MTU;
 
 	/* Invoke PMD device initialization function */
 	diag = (*eth_drv->eth_dev_init)(eth_drv, eth_dev);
@@ -1228,6 +1228,43 @@ rte_eth_macaddr_get(uint8_t port_id, struct ether_addr *mac_addr)
 	ether_addr_copy(&dev->data->mac_addrs[0], mac_addr);
 }
 
+
+int
+rte_eth_dev_get_mtu(uint8_t port_id, uint16_t *mtu)
+{
+	struct rte_eth_dev *dev;
+
+	if (port_id >= nb_ports) {
+		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
+		return (-ENODEV);
+	}
+
+	dev = &rte_eth_devices[port_id];
+	*mtu = dev->data->mtu;
+	return 0;
+}
+
+int
+rte_eth_dev_set_mtu(uint8_t port_id, uint16_t mtu)
+{
+	int ret;
+	struct rte_eth_dev *dev;
+
+	if (port_id >= nb_ports) {
+		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
+		return (-ENODEV);
+	}
+
+	dev = &rte_eth_devices[port_id];
+	FUNC_PTR_OR_ERR_RET(*dev->dev_ops->mtu_set, -ENOTSUP);
+
+	ret = (*dev->dev_ops->mtu_set)(dev, mtu);
+	if (!ret)
+		dev->data->mtu = mtu;
+
+	return ret;
+}
+
 int
 rte_eth_dev_vlan_filter(uint8_t port_id, uint16_t vlan_id, int on)
 {
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 54646bb..7e490d0 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -905,6 +905,9 @@ typedef uint32_t (*eth_rx_queue_count_t)(struct rte_eth_dev *dev,
 typedef int (*eth_rx_descriptor_done_t)(void *rxq, uint16_t offset);
 /**< @Check DD bit of specific RX descriptor */
 
+typedef int (*mtu_set_t)(struct rte_eth_dev *dev, uint16_t mtu);
+/**< @internal Set MTU. */
+
 typedef int (*vlan_filter_set_t)(struct rte_eth_dev *dev,
 				  uint16_t vlan_id,
 				  int on);
@@ -1141,6 +1144,7 @@ struct eth_dev_ops {
 	eth_queue_stats_mapping_set_t queue_stats_mapping_set;
 	/**< Configure per queue stat counter mapping. */
 	eth_dev_infos_get_t        dev_infos_get; /**< Get device info. */
+	mtu_set_t                  mtu_set; /**< Set MTU. */
 	vlan_filter_set_t          vlan_filter_set;  /**< Filter VLAN Setup. */
 	vlan_tpid_set_t            vlan_tpid_set;      /**< Outer VLAN TPID Setup. */
 	vlan_strip_queue_set_t     vlan_strip_queue_set; /**< VLAN Stripping on queue. */
@@ -1261,7 +1265,7 @@ struct rte_eth_dev_data {
 	/**< Link-level information & status */
 
 	struct rte_eth_conf dev_conf;   /**< Configuration applied to device. */
-	uint16_t max_frame_size;        /**< Default is ETHER_MAX_LEN (1518). */
+	uint16_t mtu;                   /**< Maximum Transmission Unit. */
 
 	uint32_t min_rx_buf_size;
 	/**< Common rx buffer size handled by all queues */
@@ -1808,6 +1812,34 @@ extern void rte_eth_dev_info_get(uint8_t port_id,
 				 struct rte_eth_dev_info *dev_info);
 
 /**
+ * Retrieve the MTU of an Ethernet device.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param mtu
+ *   A pointer to a uint16_t where the retrieved MTU is to be stored.
+ * @return
+ *   - (0) if successful.
+ *   - (-ENODEV) if *port_id* invalid.
+ */
+extern int rte_eth_dev_get_mtu(uint8_t port_id, uint16_t *mtu);
+
+/**
+ * Change the MTU of an Ethernet device.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param mtu
+ *   A uint16_t for the MTU to be applied.
+ * @return
+ *   - (0) if successful.
+ *   - (-ENOTSUP) if operation is not supported.
+ *   - (-ENODEV) if *port_id* invalid.
+ *   - (-EINVAL) if *mtu* invalid.
+ */
+extern int rte_eth_dev_set_mtu(uint8_t port_id, uint16_t mtu);
+
+/**
  * Enable/Disable hardware filtering by an Ethernet device of received
  * VLAN packets tagged with a given VLAN Tag Identifier.
  *
diff --git a/lib/librte_pmd_e1000/em_ethdev.c b/lib/librte_pmd_e1000/em_ethdev.c
index 657f843..328a2e7 100644
--- a/lib/librte_pmd_e1000/em_ethdev.c
+++ b/lib/librte_pmd_e1000/em_ethdev.c
@@ -94,6 +94,8 @@ static void em_hw_control_release(struct e1000_hw *hw);
 static void em_init_manageability(struct e1000_hw *hw);
 static void em_release_manageability(struct e1000_hw *hw);
 
+static int eth_em_mtu_set(struct rte_eth_dev *dev, uint16_t mtu);
+
 static int eth_em_vlan_filter_set(struct rte_eth_dev *dev,
 		uint16_t vlan_id, int on);
 static void eth_em_vlan_offload_set(struct rte_eth_dev *dev, int mask);
@@ -145,6 +147,7 @@ static struct eth_dev_ops eth_em_ops = {
 	.stats_get            = eth_em_stats_get,
 	.stats_reset          = eth_em_stats_reset,
 	.dev_infos_get        = eth_em_infos_get,
+	.mtu_set              = eth_em_mtu_set,
 	.vlan_filter_set      = eth_em_vlan_filter_set,
 	.vlan_offload_set     = eth_em_vlan_offload_set,
 	.rx_queue_setup       = eth_em_rx_queue_setup,
@@ -1482,6 +1485,45 @@ eth_em_rar_clear(struct rte_eth_dev *dev, uint32_t index)
 	e1000_rar_set(hw, addr, index);
 }
 
+static int
+eth_em_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
+{
+	struct rte_eth_dev_info dev_info;
+	struct e1000_hw *hw;
+	uint32_t frame_size;
+	uint32_t rctl;
+
+	eth_em_infos_get(dev, &dev_info);
+	frame_size = mtu + ETHER_HDR_LEN + ETHER_CRC_LEN + VLAN_TAG_SIZE;
+
+	/* check that mtu is within the allowed range */
+	if ((mtu < 68) || (frame_size > dev_info.max_rx_pktlen))
+		return -EINVAL;
+
+	/* refuse mtu that requires the support of scattered packets when this
+	 * feature has not been enabled before. */
+	if (!dev->data->scattered_rx &&
+	    frame_size > dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM)
+		return -EINVAL;
+
+	hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	rctl = E1000_READ_REG(hw, E1000_RCTL);
+
+	/* switch to jumbo mode if needed */
+	if (frame_size > ETHER_MAX_LEN) {
+		dev->data->dev_conf.rxmode.jumbo_frame = 1;
+		rctl |= E1000_RCTL_LPE;
+	} else {
+		dev->data->dev_conf.rxmode.jumbo_frame = 0;
+		rctl &= ~E1000_RCTL_LPE;
+	}
+	E1000_WRITE_REG(hw, E1000_RCTL, rctl);
+
+	/* update max frame size */
+	dev->data->dev_conf.rxmode.max_rx_pkt_len = frame_size;
+	return 0;
+}
+
 struct rte_driver em_pmd_drv = {
 	.type = PMD_PDEV,
 	.init = rte_em_pmd_init,
diff --git a/lib/librte_pmd_e1000/igb_ethdev.c b/lib/librte_pmd_e1000/igb_ethdev.c
index a2f1af9..402361c 100644
--- a/lib/librte_pmd_e1000/igb_ethdev.c
+++ b/lib/librte_pmd_e1000/igb_ethdev.c
@@ -87,6 +87,8 @@ static void igb_hw_control_release(struct e1000_hw *hw);
 static void igb_init_manageability(struct e1000_hw *hw);
 static void igb_release_manageability(struct e1000_hw *hw);
 
+static int  eth_igb_mtu_set(struct rte_eth_dev *dev, uint16_t mtu);
+
 static int eth_igb_vlan_filter_set(struct rte_eth_dev *dev,
 		uint16_t vlan_id, int on);
 static void eth_igb_vlan_tpid_set(struct rte_eth_dev *dev, uint16_t tpid_id);
@@ -180,6 +182,7 @@ static struct eth_dev_ops eth_igb_ops = {
 	.stats_get            = eth_igb_stats_get,
 	.stats_reset          = eth_igb_stats_reset,
 	.dev_infos_get        = eth_igb_infos_get,
+	.mtu_set              = eth_igb_mtu_set,
 	.vlan_filter_set      = eth_igb_vlan_filter_set,
 	.vlan_tpid_set        = eth_igb_vlan_tpid_set,
 	.vlan_offload_set     = eth_igb_vlan_offload_set,
@@ -2233,6 +2236,56 @@ eth_igb_rss_reta_query(struct rte_eth_dev *dev,
 	return 0;
 }
 
+static int
+eth_igb_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
+{
+	uint32_t rctl;
+	struct e1000_hw *hw;
+	struct rte_eth_dev_info dev_info;
+	uint32_t frame_size = mtu + (ETHER_HDR_LEN + ETHER_CRC_LEN +
+				     VLAN_TAG_SIZE);
+
+	hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+
+#ifdef RTE_LIBRTE_82571_SUPPORT
+	/* XXX: not bigger than max_rx_pktlen */
+	if (hw->mac.type == e1000_82571)
+		return -ENOTSUP;
+#endif
+	eth_igb_infos_get(dev, &dev_info);
+
+	/* check that mtu is within the allowed range */
+	if ((mtu < 68) ||
+	    (frame_size > dev_info.max_rx_pktlen))
+		return -EINVAL;
+
+	/* refuse mtu that requires the support of scattered packets when this
+	 * feature has not been enabled before. */
+	if (!dev->data->scattered_rx &&
+	    frame_size > dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM)
+		return -EINVAL;
+
+	rctl = E1000_READ_REG(hw, E1000_RCTL);
+
+	/* switch to jumbo mode if needed */
+	if (frame_size > ETHER_MAX_LEN) {
+		dev->data->dev_conf.rxmode.jumbo_frame = 1;
+		rctl |= E1000_RCTL_LPE;
+	} else {
+		dev->data->dev_conf.rxmode.jumbo_frame = 0;
+		rctl &= ~E1000_RCTL_LPE;
+	}
+	E1000_WRITE_REG(hw, E1000_RCTL, rctl);
+
+	/* update max frame size */
+	dev->data->dev_conf.rxmode.max_rx_pkt_len = frame_size;
+
+	E1000_WRITE_REG(hw, E1000_RLPML,
+			dev->data->dev_conf.rxmode.max_rx_pkt_len);
+
+	return 0;
+}
+
 static struct rte_driver pmd_igb_drv = {
 	.type = PMD_PDEV,
 	.init = rte_igb_pmd_init,
diff --git a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
index 5c846e5..43d0683 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
+++ b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
@@ -118,6 +118,9 @@ static int ixgbe_dev_queue_stats_mapping_set(struct rte_eth_dev *eth_dev,
 					     uint8_t is_rx);
 static void ixgbe_dev_info_get(struct rte_eth_dev *dev,
 				struct rte_eth_dev_info *dev_info);
+
+static int ixgbe_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu);
+
 static int ixgbe_vlan_filter_set(struct rte_eth_dev *dev,
 		uint16_t vlan_id, int on);
 static void ixgbe_vlan_tpid_set(struct rte_eth_dev *dev, uint16_t tpid_id);
@@ -275,6 +278,7 @@ static struct eth_dev_ops ixgbe_eth_dev_ops = {
 	.stats_reset          = ixgbe_dev_stats_reset,
 	.queue_stats_mapping_set = ixgbe_dev_queue_stats_mapping_set,
 	.dev_infos_get        = ixgbe_dev_info_get,
+	.mtu_set              = ixgbe_dev_mtu_set,
 	.vlan_filter_set      = ixgbe_vlan_filter_set,
 	.vlan_tpid_set        = ixgbe_vlan_tpid_set,
 	.vlan_offload_set     = ixgbe_vlan_offload_set,
@@ -2673,6 +2677,51 @@ ixgbe_remove_rar(struct rte_eth_dev *dev, uint32_t index)
 	ixgbe_clear_rar(hw, index);
 }
 
+static int
+ixgbe_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
+{
+	uint32_t hlreg0;
+	uint32_t maxfrs;
+	struct ixgbe_hw *hw;
+	struct rte_eth_dev_info dev_info;
+	uint32_t frame_size = mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
+
+	ixgbe_dev_info_get(dev, &dev_info);
+
+	/* check that mtu is within the allowed range */
+	if ((mtu < 68) || (frame_size > dev_info.max_rx_pktlen))
+		return -EINVAL;
+
+	/* refuse mtu that requires the support of scattered packets when this
+	 * feature has not been enabled before. */
+	if (!dev->data->scattered_rx &&
+	    frame_size > dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM)
+		return -EINVAL;
+
+	hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	hlreg0 = IXGBE_READ_REG(hw, IXGBE_HLREG0);
+
+	/* switch to jumbo mode if needed */
+	if (frame_size > ETHER_MAX_LEN) {
+		dev->data->dev_conf.rxmode.jumbo_frame = 1;
+		hlreg0 |= IXGBE_HLREG0_JUMBOEN;
+	} else {
+		dev->data->dev_conf.rxmode.jumbo_frame = 0;
+		hlreg0 &= ~IXGBE_HLREG0_JUMBOEN;
+	}
+	IXGBE_WRITE_REG(hw, IXGBE_HLREG0, hlreg0);
+
+	/* update max frame size */
+	dev->data->dev_conf.rxmode.max_rx_pkt_len = frame_size;
+
+	maxfrs = IXGBE_READ_REG(hw, IXGBE_MAXFRS);
+	maxfrs &= 0x0000FFFF;
+	maxfrs |= (dev->data->dev_conf.rxmode.max_rx_pkt_len << 16);
+	IXGBE_WRITE_REG(hw, IXGBE_MAXFRS, maxfrs);
+
+	return 0;
+}
+
 /*
  * Virtual Function operations
  */
diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
index a2f6413..43b7d0b 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
@@ -2878,7 +2878,7 @@ ixgbe_dcb_hw_configure(struct rte_eth_dev *dev,
 	uint16_t max[IXGBE_DCB_MAX_TRAFFIC_CLASS] = {0};
 	uint8_t map[IXGBE_DCB_MAX_TRAFFIC_CLASS] = {0};
 	struct ixgbe_dcb_tc_config *tc;
-	uint32_t max_frame = dev->data->max_frame_size;
+	uint32_t max_frame = dev->data->mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
 	struct ixgbe_hw *hw =
 			IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 
-- 
1.7.10.4