[mirror_ubuntu-artful-kernel.git] / drivers / net / ntb_netdev.c

/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 *   redistributing this file, you may do so under either license.
 *
 *   GPL LICENSE SUMMARY
 *
 *   Copyright(c) 2012 Intel Corporation. All rights reserved.
 *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of version 2 of the GNU General Public License as
 *   published by the Free Software Foundation.
 *
 *   BSD LICENSE
 *
 *   Copyright(c) 2012 Intel Corporation. All rights reserved.
 *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copy
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * PCIe NTB Network Linux driver
 *
 * Contact Information:
 * Jon Mason <jon.mason@intel.com>
 */
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/ntb.h>
#include <linux/ntb_transport.h>

#define NTB_NETDEV_VER	"0.7"

MODULE_DESCRIPTION(KBUILD_MODNAME);
MODULE_VERSION(NTB_NETDEV_VER);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Intel Corporation");

/* Time in usecs for tx resource reaper */
static unsigned int tx_time = 1;

/* Number of descriptors to free before resuming tx */
static unsigned int tx_start = 10;

/* Number of descriptors still available before stop upper layer tx */
static unsigned int tx_stop = 5;

struct ntb_netdev {
	struct list_head list;
	struct pci_dev *pdev;
	struct net_device *ndev;
	struct ntb_transport_qp *qp;
	struct timer_list tx_timer;
};

#define	NTB_TX_TIMEOUT_MS	1000
#define	NTB_RXQ_SIZE		100

static LIST_HEAD(dev_list);

static void ntb_netdev_event_handler(void *data, int link_is_up)
{
	struct net_device *ndev = data;
	struct ntb_netdev *dev = netdev_priv(ndev);

	netdev_dbg(ndev, "Event %x, Link %x\n", link_is_up,
		   ntb_transport_link_query(dev->qp));

	if (link_is_up) {
		if (ntb_transport_link_query(dev->qp))
			netif_carrier_on(ndev);
	} else {
		netif_carrier_off(ndev);
	}
}

static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
				  void *data, int len)
{
	struct net_device *ndev = qp_data;
	struct sk_buff *skb;
	int rc;

	skb = data;
	if (!skb)
		return;

	netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);

	if (len < 0) {
		ndev->stats.rx_errors++;
		ndev->stats.rx_length_errors++;
		goto enqueue_again;
	}

	skb_put(skb, len);
	skb->protocol = eth_type_trans(skb, ndev);
	skb->ip_summed = CHECKSUM_NONE;

	if (netif_rx(skb) == NET_RX_DROP) {
		ndev->stats.rx_errors++;
		ndev->stats.rx_dropped++;
	} else {
		ndev->stats.rx_packets++;
		ndev->stats.rx_bytes += len;
	}

	skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
	if (!skb) {
		ndev->stats.rx_errors++;
		ndev->stats.rx_frame_errors++;
		return;
	}

enqueue_again:
	rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
	if (rc) {
		dev_kfree_skb(skb);
		ndev->stats.rx_errors++;
		ndev->stats.rx_fifo_errors++;
	}
}

static int __ntb_netdev_maybe_stop_tx(struct net_device *netdev,
				      struct ntb_transport_qp *qp, int size)
{
	struct ntb_netdev *dev = netdev_priv(netdev);

	netif_stop_queue(netdev);
	/* Make sure to see the latest value of ntb_transport_tx_free_entry()
	 * since the queue was last started.
	 */
	smp_mb();

	if (likely(ntb_transport_tx_free_entry(qp) < size)) {
		mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time));
		return -EBUSY;
	}

	netif_start_queue(netdev);
	return 0;
}

static int ntb_netdev_maybe_stop_tx(struct net_device *ndev,
				    struct ntb_transport_qp *qp, int size)
{
	if (netif_queue_stopped(ndev) ||
	    (ntb_transport_tx_free_entry(qp) >= size))
		return 0;

	return __ntb_netdev_maybe_stop_tx(ndev, qp, size);
}

static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
				  void *data, int len)
{
	struct net_device *ndev = qp_data;
	struct sk_buff *skb;
	struct ntb_netdev *dev = netdev_priv(ndev);

	skb = data;
	if (!skb || !ndev)
		return;

	if (len > 0) {
		ndev->stats.tx_packets++;
		ndev->stats.tx_bytes += skb->len;
	} else {
		ndev->stats.tx_errors++;
		ndev->stats.tx_aborted_errors++;
	}

	dev_kfree_skb(skb);

	if (ntb_transport_tx_free_entry(dev->qp) >= tx_start) {
		/* Make sure anybody stopping the queue after this sees the new
		 * value of ntb_transport_tx_free_entry()
		 */
		smp_mb();
		if (netif_queue_stopped(ndev))
			netif_wake_queue(ndev);
	}
}

static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
					 struct net_device *ndev)
{
	struct ntb_netdev *dev = netdev_priv(ndev);
	int rc;

	ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);

	rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
	if (rc)
		goto err;

	/* check for next submit */
	ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);

	return NETDEV_TX_OK;

err:
	ndev->stats.tx_dropped++;
	ndev->stats.tx_errors++;
	return NETDEV_TX_BUSY;
}

static void ntb_netdev_tx_timer(unsigned long data)
{
	struct net_device *ndev = (struct net_device *)data;
	struct ntb_netdev *dev = netdev_priv(ndev);

	if (ntb_transport_tx_free_entry(dev->qp) < tx_stop) {
		mod_timer(&dev->tx_timer, jiffies + msecs_to_jiffies(tx_time));
	} else {
		/* Make sure anybody stopping the queue after this sees the new
		 * value of ntb_transport_tx_free_entry()
		 */
		smp_mb();
		if (netif_queue_stopped(ndev))
			netif_wake_queue(ndev);
	}
}

static int ntb_netdev_open(struct net_device *ndev)
{
	struct ntb_netdev *dev = netdev_priv(ndev);
	struct sk_buff *skb;
	int rc, i, len;

	/* Add some empty rx bufs */
	for (i = 0; i < NTB_RXQ_SIZE; i++) {
		skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
		if (!skb) {
			rc = -ENOMEM;
			goto err;
		}

		rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
					      ndev->mtu + ETH_HLEN);
		if (rc) {
			dev_kfree_skb(skb);
			goto err;
		}
	}

	setup_timer(&dev->tx_timer, ntb_netdev_tx_timer, (unsigned long)ndev);

	netif_carrier_off(ndev);
	ntb_transport_link_up(dev->qp);
	netif_start_queue(ndev);

	return 0;

err:
	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
		dev_kfree_skb(skb);
	return rc;
}

static int ntb_netdev_close(struct net_device *ndev)
{
	struct ntb_netdev *dev = netdev_priv(ndev);
	struct sk_buff *skb;
	int len;

	ntb_transport_link_down(dev->qp);

	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
		dev_kfree_skb(skb);

	del_timer_sync(&dev->tx_timer);

	return 0;
}

static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
{
	struct ntb_netdev *dev = netdev_priv(ndev);
	struct sk_buff *skb;
	int len, rc;

	if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
		return -EINVAL;

	if (!netif_running(ndev)) {
		ndev->mtu = new_mtu;
		return 0;
	}

	/* Bring down the link and dispose of posted rx entries */
	ntb_transport_link_down(dev->qp);

	if (ndev->mtu < new_mtu) {
		int i;

		for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
			dev_kfree_skb(skb);

		for (; i; i--) {
			skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
			if (!skb) {
				rc = -ENOMEM;
				goto err;
			}

			rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
						      new_mtu + ETH_HLEN);
			if (rc) {
				dev_kfree_skb(skb);
				goto err;
			}
		}
	}

	ndev->mtu = new_mtu;

	ntb_transport_link_up(dev->qp);

	return 0;

err:
	ntb_transport_link_down(dev->qp);

	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
		dev_kfree_skb(skb);

	netdev_err(ndev, "Error changing MTU, device inoperable\n");
	return rc;
}

static const struct net_device_ops ntb_netdev_ops = {
	.ndo_open = ntb_netdev_open,
	.ndo_stop = ntb_netdev_close,
	.ndo_start_xmit = ntb_netdev_start_xmit,
	.ndo_change_mtu = ntb_netdev_change_mtu,
	.ndo_set_mac_address = eth_mac_addr,
};

static void ntb_get_drvinfo(struct net_device *ndev,
			    struct ethtool_drvinfo *info)
{
	struct ntb_netdev *dev = netdev_priv(ndev);

	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
	strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
	strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
}

static int ntb_get_link_ksettings(struct net_device *dev,
				  struct ethtool_link_ksettings *cmd)
{
	ethtool_link_ksettings_zero_link_mode(cmd, supported);
	ethtool_link_ksettings_add_link_mode(cmd, supported, Backplane);
	ethtool_link_ksettings_zero_link_mode(cmd, advertising);
	ethtool_link_ksettings_add_link_mode(cmd, advertising, Backplane);

	cmd->base.speed = SPEED_UNKNOWN;
	cmd->base.duplex = DUPLEX_FULL;
	cmd->base.port = PORT_OTHER;
	cmd->base.phy_address = 0;
	cmd->base.autoneg = AUTONEG_ENABLE;

	return 0;
}

static const struct ethtool_ops ntb_ethtool_ops = {
	.get_drvinfo = ntb_get_drvinfo,
	.get_link = ethtool_op_get_link,
	.get_link_ksettings = ntb_get_link_ksettings,
};

static const struct ntb_queue_handlers ntb_netdev_handlers = {
	.tx_handler = ntb_netdev_tx_handler,
	.rx_handler = ntb_netdev_rx_handler,
	.event_handler = ntb_netdev_event_handler,
};

static int ntb_netdev_probe(struct device *client_dev)
{
	struct ntb_dev *ntb;
	struct net_device *ndev;
	struct pci_dev *pdev;
	struct ntb_netdev *dev;
	int rc;

	ntb = dev_ntb(client_dev->parent);
	pdev = ntb->pdev;
	if (!pdev)
		return -ENODEV;

	ndev = alloc_etherdev(sizeof(*dev));
	if (!ndev)
		return -ENOMEM;

	SET_NETDEV_DEV(ndev, client_dev);

	dev = netdev_priv(ndev);
	dev->ndev = ndev;
	dev->pdev = pdev;
	ndev->features = NETIF_F_HIGHDMA;

	ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;

	ndev->hw_features = ndev->features;
	ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);

	random_ether_addr(ndev->perm_addr);
	memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);

	ndev->netdev_ops = &ntb_netdev_ops;
	ndev->ethtool_ops = &ntb_ethtool_ops;

	ndev->min_mtu = 0;
	ndev->max_mtu = ETH_MAX_MTU;

	dev->qp = ntb_transport_create_queue(ndev, client_dev,
					     &ntb_netdev_handlers);
	if (!dev->qp) {
		rc = -EIO;
		goto err;
	}

	ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;

	rc = register_netdev(ndev);
	if (rc)
		goto err1;

	list_add(&dev->list, &dev_list);
	dev_info(&pdev->dev, "%s created\n", ndev->name);
	return 0;

err1:
	ntb_transport_free_queue(dev->qp);
err:
	free_netdev(ndev);
	return rc;
}

static void ntb_netdev_remove(struct device *client_dev)
{
	struct ntb_dev *ntb;
	struct net_device *ndev;
	struct pci_dev *pdev;
	struct ntb_netdev *dev;
	bool found = false;

	ntb = dev_ntb(client_dev->parent);
	pdev = ntb->pdev;

	list_for_each_entry(dev, &dev_list, list) {
		if (dev->pdev == pdev) {
			found = true;
			break;
		}
	}
	if (!found)
		return;

	list_del(&dev->list);

	ndev = dev->ndev;

	unregister_netdev(ndev);
	ntb_transport_free_queue(dev->qp);
	free_netdev(ndev);
}

static struct ntb_transport_client ntb_netdev_client = {
	.driver.name = KBUILD_MODNAME,
	.driver.owner = THIS_MODULE,
	.probe = ntb_netdev_probe,
	.remove = ntb_netdev_remove,
};

static int __init ntb_netdev_init_module(void)
{
	int rc;

	rc = ntb_transport_register_client_dev(KBUILD_MODNAME);
	if (rc)
		return rc;
	return ntb_transport_register_client(&ntb_netdev_client);
}
module_init(ntb_netdev_init_module);

static void __exit ntb_netdev_exit_module(void)
{
	ntb_transport_unregister_client(&ntb_netdev_client);
	ntb_transport_unregister_client_dev(KBUILD_MODNAME);
}
module_exit(ntb_netdev_exit_module);
Commit	Line	Data
548c237c JM	1	/*
	2	* This file is provided under a dual BSD/GPLv2 license. When using or
	3	* redistributing this file, you may do so under either license.
	4	*
	5	* GPL LICENSE SUMMARY
	6	*
	7	* Copyright(c) 2012 Intel Corporation. All rights reserved.
e26a5843	8	* Copyright (C) 2015 EMC Corporation. All Rights Reserved.
548c237c JM	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of version 2 of the GNU General Public License as
	12	* published by the Free Software Foundation.
	13	*
	14	* BSD LICENSE
	15	*
	16	* Copyright(c) 2012 Intel Corporation. All rights reserved.
e26a5843	17	* Copyright (C) 2015 EMC Corporation. All Rights Reserved.
548c237c JM	18	*
	19	* Redistribution and use in source and binary forms, with or without
	20	* modification, are permitted provided that the following conditions
	21	* are met:
	22	*
	23	* * Redistributions of source code must retain the above copyright
	24	* notice, this list of conditions and the following disclaimer.
	25	* * Redistributions in binary form must reproduce the above copy
	26	* notice, this list of conditions and the following disclaimer in
	27	* the documentation and/or other materials provided with the
	28	* distribution.
	29	* * Neither the name of Intel Corporation nor the names of its
	30	* contributors may be used to endorse or promote products derived
	31	* from this software without specific prior written permission.
	32	*
	33	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	34	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	35	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	36	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	37	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	38	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	39	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	40	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	41	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	42	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	43	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	44	*
e26a5843	45	* PCIe NTB Network Linux driver
548c237c JM	46	*
	47	* Contact Information:
	48	* Jon Mason <jon.mason@intel.com>
	49	*/
	50	#include <linux/etherdevice.h>
	51	#include <linux/ethtool.h>
	52	#include <linux/module.h>
	53	#include <linux/pci.h>
e26a5843	54	#include <linux/ntb.h>
ec110bc7	55	#include <linux/ntb_transport.h>
548c237c	56
24208bbe	57	#define NTB_NETDEV_VER "0.7"
548c237c JM	58
	59	MODULE_DESCRIPTION(KBUILD_MODNAME);
	60	MODULE_VERSION(NTB_NETDEV_VER);
	61	MODULE_LICENSE("Dual BSD/GPL");
	62	MODULE_AUTHOR("Intel Corporation");
	63
e74bfeed DJ	64	/* Time in usecs for tx resource reaper */
	65	static unsigned int tx_time = 1;
	66
	67	/* Number of descriptors to free before resuming tx */
	68	static unsigned int tx_start = 10;
	69
	70	/* Number of descriptors still available before stop upper layer tx */
	71	static unsigned int tx_stop = 5;
	72
548c237c JM	73	struct ntb_netdev {
	74	struct list_head list;
	75	struct pci_dev *pdev;
	76	struct net_device *ndev;
	77	struct ntb_transport_qp *qp;
e74bfeed	78	struct timer_list tx_timer;
548c237c JM	79	};
	80
	81	#define NTB_TX_TIMEOUT_MS 1000
	82	#define NTB_RXQ_SIZE 100
	83
	84	static LIST_HEAD(dev_list);
	85
e26a5843	86	static void ntb_netdev_event_handler(void *data, int link_is_up)
548c237c JM	87	{
	88	struct net_device *ndev = data;
	89	struct ntb_netdev *dev = netdev_priv(ndev);
	90
e26a5843	91	netdev_dbg(ndev, "Event %x, Link %x\n", link_is_up,
548c237c JM	92	ntb_transport_link_query(dev->qp));
548c237c JM	93
e26a5843 AH	94	if (link_is_up) {
	95	if (ntb_transport_link_query(dev->qp))
	96	netif_carrier_on(ndev);
	97	} else {
548c237c	98	netif_carrier_off(ndev);
403c63cb	99	}
548c237c JM	100	}
	101
	102	static void ntb_netdev_rx_handler(struct ntb_transport_qp qp, void qp_data,
	103	void *data, int len)
	104	{
	105	struct net_device *ndev = qp_data;
	106	struct sk_buff *skb;
	107	int rc;
	108
	109	skb = data;
	110	if (!skb)
	111	return;
	112
	113	netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);
	114
da2e5ae5 AH	115	if (len < 0) {
	116	ndev->stats.rx_errors++;
	117	ndev->stats.rx_length_errors++;
	118	goto enqueue_again;
	119	}
	120
548c237c JM	121	skb_put(skb, len);
	122	skb->protocol = eth_type_trans(skb, ndev);
	123	skb->ip_summed = CHECKSUM_NONE;
	124
	125	if (netif_rx(skb) == NET_RX_DROP) {
	126	ndev->stats.rx_errors++;
	127	ndev->stats.rx_dropped++;
	128	} else {
	129	ndev->stats.rx_packets++;
	130	ndev->stats.rx_bytes += len;
	131	}
	132
	133	skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
	134	if (!skb) {
	135	ndev->stats.rx_errors++;
	136	ndev->stats.rx_frame_errors++;
	137	return;
	138	}
	139
da2e5ae5	140	enqueue_again:
548c237c JM	141	rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
548c237c JM	142	if (rc) {
765ccc7b	143	dev_kfree_skb(skb);
548c237c JM	144	ndev->stats.rx_errors++;
	145	ndev->stats.rx_fifo_errors++;
	146	}
	147	}
	148
e74bfeed DJ	149	static int __ntb_netdev_maybe_stop_tx(struct net_device *netdev,
	150	struct ntb_transport_qp *qp, int size)
	151	{
	152	struct ntb_netdev *dev = netdev_priv(netdev);
	153
	154	netif_stop_queue(netdev);
	155	/* Make sure to see the latest value of ntb_transport_tx_free_entry()
	156	* since the queue was last started.
	157	*/
	158	smp_mb();
	159
	160	if (likely(ntb_transport_tx_free_entry(qp) < size)) {
	161	mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time));
	162	return -EBUSY;
	163	}
	164
	165	netif_start_queue(netdev);
	166	return 0;
	167	}
	168
	169	static int ntb_netdev_maybe_stop_tx(struct net_device *ndev,
	170	struct ntb_transport_qp *qp, int size)
	171	{
	172	if (netif_queue_stopped(ndev) \|\|
	173	(ntb_transport_tx_free_entry(qp) >= size))
	174	return 0;
	175
	176	return __ntb_netdev_maybe_stop_tx(ndev, qp, size);
	177	}
	178
548c237c JM	179	static void ntb_netdev_tx_handler(struct ntb_transport_qp qp, void qp_data,
	180	void *data, int len)
	181	{
	182	struct net_device *ndev = qp_data;
	183	struct sk_buff *skb;
e74bfeed	184	struct ntb_netdev *dev = netdev_priv(ndev);
548c237c JM	185
	186	skb = data;
	187	if (!skb \|\| !ndev)
	188	return;
	189
	190	if (len > 0) {
	191	ndev->stats.tx_packets++;
	192	ndev->stats.tx_bytes += skb->len;
	193	} else {
	194	ndev->stats.tx_errors++;
	195	ndev->stats.tx_aborted_errors++;
	196	}
	197
	198	dev_kfree_skb(skb);
e74bfeed DJ	199
	200	if (ntb_transport_tx_free_entry(dev->qp) >= tx_start) {
	201	/* Make sure anybody stopping the queue after this sees the new
	202	* value of ntb_transport_tx_free_entry()
	203	*/
	204	smp_mb();
	205	if (netif_queue_stopped(ndev))
	206	netif_wake_queue(ndev);
	207	}
548c237c JM	208	}
	209
	210	static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
	211	struct net_device *ndev)
	212	{
	213	struct ntb_netdev *dev = netdev_priv(ndev);
	214	int rc;
	215
e74bfeed DJ	216	ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
e74bfeed DJ	217
548c237c JM	218	rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
	219	if (rc)
	220	goto err;
	221
e74bfeed DJ	222	/* check for next submit */
	223	ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
	224
548c237c JM	225	return NETDEV_TX_OK;
	226
	227	err:
	228	ndev->stats.tx_dropped++;
	229	ndev->stats.tx_errors++;
548c237c JM	230	return NETDEV_TX_BUSY;
	231	}
	232
e74bfeed DJ	233	static void ntb_netdev_tx_timer(unsigned long data)
	234	{
	235	struct net_device ndev = (struct net_device )data;
	236	struct ntb_netdev *dev = netdev_priv(ndev);
	237
	238	if (ntb_transport_tx_free_entry(dev->qp) < tx_stop) {
	239	mod_timer(&dev->tx_timer, jiffies + msecs_to_jiffies(tx_time));
	240	} else {
	241	/* Make sure anybody stopping the queue after this sees the new
	242	* value of ntb_transport_tx_free_entry()
	243	*/
	244	smp_mb();
	245	if (netif_queue_stopped(ndev))
	246	netif_wake_queue(ndev);
	247	}
	248	}
	249
548c237c JM	250	static int ntb_netdev_open(struct net_device *ndev)
	251	{
	252	struct ntb_netdev *dev = netdev_priv(ndev);
	253	struct sk_buff *skb;
	254	int rc, i, len;
	255
	256	/* Add some empty rx bufs */
	257	for (i = 0; i < NTB_RXQ_SIZE; i++) {
	258	skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
	259	if (!skb) {
	260	rc = -ENOMEM;
	261	goto err;
	262	}
	263
	264	rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
	265	ndev->mtu + ETH_HLEN);
da4eb27a	266	if (rc) {
e8bc2ebd	267	dev_kfree_skb(skb);
548c237c	268	goto err;
e8bc2ebd	269	}
548c237c JM	270	}
548c237c JM	271
e74bfeed DJ	272	setup_timer(&dev->tx_timer, ntb_netdev_tx_timer, (unsigned long)ndev);
e74bfeed DJ	273
548c237c JM	274	netif_carrier_off(ndev);
548c237c JM	275	ntb_transport_link_up(dev->qp);
e74bfeed	276	netif_start_queue(ndev);
548c237c JM	277
	278	return 0;
	279
	280	err:
	281	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
	282	dev_kfree_skb(skb);
	283	return rc;
	284	}
	285
	286	static int ntb_netdev_close(struct net_device *ndev)
	287	{
	288	struct ntb_netdev *dev = netdev_priv(ndev);
	289	struct sk_buff *skb;
	290	int len;
	291
	292	ntb_transport_link_down(dev->qp);
	293
	294	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
	295	dev_kfree_skb(skb);
	296
e74bfeed DJ	297	del_timer_sync(&dev->tx_timer);
e74bfeed DJ	298
548c237c JM	299	return 0;
	300	}
	301
	302	static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
	303	{
	304	struct ntb_netdev *dev = netdev_priv(ndev);
	305	struct sk_buff *skb;
	306	int len, rc;
	307
	308	if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
	309	return -EINVAL;
	310
	311	if (!netif_running(ndev)) {
	312	ndev->mtu = new_mtu;
	313	return 0;
	314	}
	315
	316	/* Bring down the link and dispose of posted rx entries */
	317	ntb_transport_link_down(dev->qp);
	318
	319	if (ndev->mtu < new_mtu) {
	320	int i;
	321
	322	for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
	323	dev_kfree_skb(skb);
	324
	325	for (; i; i--) {
	326	skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
	327	if (!skb) {
	328	rc = -ENOMEM;
	329	goto err;
	330	}
	331
	332	rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
	333	new_mtu + ETH_HLEN);
	334	if (rc) {
	335	dev_kfree_skb(skb);
	336	goto err;
	337	}
	338	}
	339	}
	340
	341	ndev->mtu = new_mtu;
	342
	343	ntb_transport_link_up(dev->qp);
	344
	345	return 0;
	346
	347	err:
	348	ntb_transport_link_down(dev->qp);
	349
	350	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
	351	dev_kfree_skb(skb);
	352
	353	netdev_err(ndev, "Error changing MTU, device inoperable\n");
	354	return rc;
	355	}
	356
548c237c JM	357	static const struct net_device_ops ntb_netdev_ops = {
	358	.ndo_open = ntb_netdev_open,
	359	.ndo_stop = ntb_netdev_close,
	360	.ndo_start_xmit = ntb_netdev_start_xmit,
	361	.ndo_change_mtu = ntb_netdev_change_mtu,
548c237c JM	362	.ndo_set_mac_address = eth_mac_addr,
	363	};
	364
	365	static void ntb_get_drvinfo(struct net_device *ndev,
	366	struct ethtool_drvinfo *info)
	367	{
	368	struct ntb_netdev *dev = netdev_priv(ndev);
	369
	370	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
	371	strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
	372	strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
	373	}
	374
a062d19e PR	375	static int ntb_get_link_ksettings(struct net_device *dev,
a062d19e PR	376	struct ethtool_link_ksettings *cmd)
548c237c	377	{
a062d19e PR	378	ethtool_link_ksettings_zero_link_mode(cmd, supported);
	379	ethtool_link_ksettings_add_link_mode(cmd, supported, Backplane);
	380	ethtool_link_ksettings_zero_link_mode(cmd, advertising);
	381	ethtool_link_ksettings_add_link_mode(cmd, advertising, Backplane);
	382
	383	cmd->base.speed = SPEED_UNKNOWN;
	384	cmd->base.duplex = DUPLEX_FULL;
	385	cmd->base.port = PORT_OTHER;
	386	cmd->base.phy_address = 0;
	387	cmd->base.autoneg = AUTONEG_ENABLE;
548c237c JM	388
	389	return 0;
	390	}
	391
	392	static const struct ethtool_ops ntb_ethtool_ops = {
	393	.get_drvinfo = ntb_get_drvinfo,
	394	.get_link = ethtool_op_get_link,
a062d19e	395	.get_link_ksettings = ntb_get_link_ksettings,
548c237c JM	396	};
	397
	398	static const struct ntb_queue_handlers ntb_netdev_handlers = {
	399	.tx_handler = ntb_netdev_tx_handler,
	400	.rx_handler = ntb_netdev_rx_handler,
	401	.event_handler = ntb_netdev_event_handler,
	402	};
	403
e26a5843	404	static int ntb_netdev_probe(struct device *client_dev)
548c237c	405	{
e26a5843	406	struct ntb_dev *ntb;
548c237c	407	struct net_device *ndev;
e26a5843	408	struct pci_dev *pdev;
548c237c JM	409	struct ntb_netdev *dev;
	410	int rc;
	411
e26a5843 AH	412	ntb = dev_ntb(client_dev->parent);
	413	pdev = ntb->pdev;
	414	if (!pdev)
	415	return -ENODEV;
	416
	417	ndev = alloc_etherdev(sizeof(*dev));
548c237c JM	418	if (!ndev)
	419	return -ENOMEM;
	420
854b1dd9 LG	421	SET_NETDEV_DEV(ndev, client_dev);
854b1dd9 LG	422
548c237c JM	423	dev = netdev_priv(ndev);
	424	dev->ndev = ndev;
	425	dev->pdev = pdev;
548c237c JM	426	ndev->features = NETIF_F_HIGHDMA;
	427
	428	ndev->priv_flags \|= IFF_LIVE_ADDR_CHANGE;
	429
	430	ndev->hw_features = ndev->features;
	431	ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
	432
	433	random_ether_addr(ndev->perm_addr);
	434	memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
	435
	436	ndev->netdev_ops = &ntb_netdev_ops;
7ad24ea4	437	ndev->ethtool_ops = &ntb_ethtool_ops;
548c237c	438
91572088 JW	439	ndev->min_mtu = 0;
	440	ndev->max_mtu = ETH_MAX_MTU;
	441
e26a5843 AH	442	dev->qp = ntb_transport_create_queue(ndev, client_dev,
e26a5843 AH	443	&ntb_netdev_handlers);
548c237c JM	444	if (!dev->qp) {
	445	rc = -EIO;
	446	goto err;
	447	}
	448
	449	ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
	450
	451	rc = register_netdev(ndev);
	452	if (rc)
	453	goto err1;
	454
	455	list_add(&dev->list, &dev_list);
7bcd2b11	456	dev_info(&pdev->dev, "%s created\n", ndev->name);
548c237c JM	457	return 0;
	458
	459	err1:
	460	ntb_transport_free_queue(dev->qp);
	461	err:
	462	free_netdev(ndev);
	463	return rc;
	464	}
	465
e26a5843	466	static void ntb_netdev_remove(struct device *client_dev)
548c237c	467	{
e26a5843	468	struct ntb_dev *ntb;
548c237c	469	struct net_device *ndev;
e26a5843	470	struct pci_dev *pdev;
548c237c	471	struct ntb_netdev *dev;
53ca4fea	472	bool found = false;
548c237c	473
e26a5843 AH	474	ntb = dev_ntb(client_dev->parent);
	475	pdev = ntb->pdev;
	476
548c237c	477	list_for_each_entry(dev, &dev_list, list) {
fea903ec JM	478	if (dev->pdev == pdev) {
fea903ec JM	479	found = true;
548c237c	480	break;
fea903ec	481	}
548c237c	482	}
fea903ec	483	if (!found)
548c237c JM	484	return;
548c237c JM	485
904435cf JM	486	list_del(&dev->list);
904435cf JM	487
548c237c JM	488	ndev = dev->ndev;
	489
	490	unregister_netdev(ndev);
	491	ntb_transport_free_queue(dev->qp);
	492	free_netdev(ndev);
	493	}
	494
e26a5843	495	static struct ntb_transport_client ntb_netdev_client = {
548c237c JM	496	.driver.name = KBUILD_MODNAME,
	497	.driver.owner = THIS_MODULE,
	498	.probe = ntb_netdev_probe,
	499	.remove = ntb_netdev_remove,
	500	};
	501
	502	static int __init ntb_netdev_init_module(void)
	503	{
	504	int rc;
	505
e26a5843	506	rc = ntb_transport_register_client_dev(KBUILD_MODNAME);
548c237c JM	507	if (rc)
548c237c JM	508	return rc;
ec110bc7	509	return ntb_transport_register_client(&ntb_netdev_client);
548c237c JM	510	}
	511	module_init(ntb_netdev_init_module);
	512
	513	static void __exit ntb_netdev_exit_module(void)
	514	{
ec110bc7	515	ntb_transport_unregister_client(&ntb_netdev_client);
e26a5843	516	ntb_transport_unregister_client_dev(KBUILD_MODNAME);
548c237c JM	517	}
548c237c JM	518	module_exit(ntb_netdev_exit_module);