xref: /openbmc/linux/drivers/net/ntb_netdev.c (revision 12eb4683)
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.
8  *
9  *   This program is free software; you can redistribute it and/or modify
10  *   it under the terms of version 2 of the GNU General Public License as
11  *   published by the Free Software Foundation.
12  *
13  *   BSD LICENSE
14  *
15  *   Copyright(c) 2012 Intel Corporation. All rights reserved.
16  *
17  *   Redistribution and use in source and binary forms, with or without
18  *   modification, are permitted provided that the following conditions
19  *   are met:
20  *
21  *     * Redistributions of source code must retain the above copyright
22  *       notice, this list of conditions and the following disclaimer.
23  *     * Redistributions in binary form must reproduce the above copy
24  *       notice, this list of conditions and the following disclaimer in
25  *       the documentation and/or other materials provided with the
26  *       distribution.
27  *     * Neither the name of Intel Corporation nor the names of its
28  *       contributors may be used to endorse or promote products derived
29  *       from this software without specific prior written permission.
30  *
31  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
37  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
38  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
39  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
40  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
41  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42  *
43  * Intel PCIe NTB Network Linux driver
44  *
45  * Contact Information:
46  * Jon Mason <jon.mason@intel.com>
47  */
48 #include <linux/etherdevice.h>
49 #include <linux/ethtool.h>
50 #include <linux/module.h>
51 #include <linux/pci.h>
52 #include <linux/ntb.h>
53 
54 #define NTB_NETDEV_VER	"0.7"
55 
56 MODULE_DESCRIPTION(KBUILD_MODNAME);
57 MODULE_VERSION(NTB_NETDEV_VER);
58 MODULE_LICENSE("Dual BSD/GPL");
59 MODULE_AUTHOR("Intel Corporation");
60 
61 struct ntb_netdev {
62 	struct list_head list;
63 	struct pci_dev *pdev;
64 	struct net_device *ndev;
65 	struct ntb_transport_qp *qp;
66 };
67 
68 #define	NTB_TX_TIMEOUT_MS	1000
69 #define	NTB_RXQ_SIZE		100
70 
71 static LIST_HEAD(dev_list);
72 
73 static void ntb_netdev_event_handler(void *data, int status)
74 {
75 	struct net_device *ndev = data;
76 	struct ntb_netdev *dev = netdev_priv(ndev);
77 
78 	netdev_dbg(ndev, "Event %x, Link %x\n", status,
79 		   ntb_transport_link_query(dev->qp));
80 
81 	/* Currently, only link status event is supported */
82 	if (status)
83 		netif_carrier_on(ndev);
84 	else
85 		netif_carrier_off(ndev);
86 }
87 
88 static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
89 				  void *data, int len)
90 {
91 	struct net_device *ndev = qp_data;
92 	struct sk_buff *skb;
93 	int rc;
94 
95 	skb = data;
96 	if (!skb)
97 		return;
98 
99 	netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);
100 
101 	skb_put(skb, len);
102 	skb->protocol = eth_type_trans(skb, ndev);
103 	skb->ip_summed = CHECKSUM_NONE;
104 
105 	if (netif_rx(skb) == NET_RX_DROP) {
106 		ndev->stats.rx_errors++;
107 		ndev->stats.rx_dropped++;
108 	} else {
109 		ndev->stats.rx_packets++;
110 		ndev->stats.rx_bytes += len;
111 	}
112 
113 	skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
114 	if (!skb) {
115 		ndev->stats.rx_errors++;
116 		ndev->stats.rx_frame_errors++;
117 		return;
118 	}
119 
120 	rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
121 	if (rc) {
122 		dev_kfree_skb(skb);
123 		ndev->stats.rx_errors++;
124 		ndev->stats.rx_fifo_errors++;
125 	}
126 }
127 
128 static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
129 				  void *data, int len)
130 {
131 	struct net_device *ndev = qp_data;
132 	struct sk_buff *skb;
133 
134 	skb = data;
135 	if (!skb || !ndev)
136 		return;
137 
138 	if (len > 0) {
139 		ndev->stats.tx_packets++;
140 		ndev->stats.tx_bytes += skb->len;
141 	} else {
142 		ndev->stats.tx_errors++;
143 		ndev->stats.tx_aborted_errors++;
144 	}
145 
146 	dev_kfree_skb(skb);
147 }
148 
149 static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
150 					 struct net_device *ndev)
151 {
152 	struct ntb_netdev *dev = netdev_priv(ndev);
153 	int rc;
154 
155 	netdev_dbg(ndev, "%s: skb len %d\n", __func__, skb->len);
156 
157 	rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
158 	if (rc)
159 		goto err;
160 
161 	return NETDEV_TX_OK;
162 
163 err:
164 	ndev->stats.tx_dropped++;
165 	ndev->stats.tx_errors++;
166 	return NETDEV_TX_BUSY;
167 }
168 
169 static int ntb_netdev_open(struct net_device *ndev)
170 {
171 	struct ntb_netdev *dev = netdev_priv(ndev);
172 	struct sk_buff *skb;
173 	int rc, i, len;
174 
175 	/* Add some empty rx bufs */
176 	for (i = 0; i < NTB_RXQ_SIZE; i++) {
177 		skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
178 		if (!skb) {
179 			rc = -ENOMEM;
180 			goto err;
181 		}
182 
183 		rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
184 					      ndev->mtu + ETH_HLEN);
185 		if (rc == -EINVAL)
186 			goto err;
187 	}
188 
189 	netif_carrier_off(ndev);
190 	ntb_transport_link_up(dev->qp);
191 
192 	return 0;
193 
194 err:
195 	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
196 		dev_kfree_skb(skb);
197 	return rc;
198 }
199 
200 static int ntb_netdev_close(struct net_device *ndev)
201 {
202 	struct ntb_netdev *dev = netdev_priv(ndev);
203 	struct sk_buff *skb;
204 	int len;
205 
206 	ntb_transport_link_down(dev->qp);
207 
208 	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
209 		dev_kfree_skb(skb);
210 
211 	return 0;
212 }
213 
214 static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
215 {
216 	struct ntb_netdev *dev = netdev_priv(ndev);
217 	struct sk_buff *skb;
218 	int len, rc;
219 
220 	if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
221 		return -EINVAL;
222 
223 	if (!netif_running(ndev)) {
224 		ndev->mtu = new_mtu;
225 		return 0;
226 	}
227 
228 	/* Bring down the link and dispose of posted rx entries */
229 	ntb_transport_link_down(dev->qp);
230 
231 	if (ndev->mtu < new_mtu) {
232 		int i;
233 
234 		for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
235 			dev_kfree_skb(skb);
236 
237 		for (; i; i--) {
238 			skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
239 			if (!skb) {
240 				rc = -ENOMEM;
241 				goto err;
242 			}
243 
244 			rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
245 						      new_mtu + ETH_HLEN);
246 			if (rc) {
247 				dev_kfree_skb(skb);
248 				goto err;
249 			}
250 		}
251 	}
252 
253 	ndev->mtu = new_mtu;
254 
255 	ntb_transport_link_up(dev->qp);
256 
257 	return 0;
258 
259 err:
260 	ntb_transport_link_down(dev->qp);
261 
262 	while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
263 		dev_kfree_skb(skb);
264 
265 	netdev_err(ndev, "Error changing MTU, device inoperable\n");
266 	return rc;
267 }
268 
269 static const struct net_device_ops ntb_netdev_ops = {
270 	.ndo_open = ntb_netdev_open,
271 	.ndo_stop = ntb_netdev_close,
272 	.ndo_start_xmit = ntb_netdev_start_xmit,
273 	.ndo_change_mtu = ntb_netdev_change_mtu,
274 	.ndo_set_mac_address = eth_mac_addr,
275 };
276 
277 static void ntb_get_drvinfo(struct net_device *ndev,
278 			    struct ethtool_drvinfo *info)
279 {
280 	struct ntb_netdev *dev = netdev_priv(ndev);
281 
282 	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
283 	strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
284 	strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
285 }
286 
287 static int ntb_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
288 {
289 	cmd->supported = SUPPORTED_Backplane;
290 	cmd->advertising = ADVERTISED_Backplane;
291 	cmd->speed = SPEED_UNKNOWN;
292 	ethtool_cmd_speed_set(cmd, SPEED_UNKNOWN);
293 	cmd->duplex = DUPLEX_FULL;
294 	cmd->port = PORT_OTHER;
295 	cmd->phy_address = 0;
296 	cmd->transceiver = XCVR_DUMMY1;
297 	cmd->autoneg = AUTONEG_ENABLE;
298 	cmd->maxtxpkt = 0;
299 	cmd->maxrxpkt = 0;
300 
301 	return 0;
302 }
303 
304 static const struct ethtool_ops ntb_ethtool_ops = {
305 	.get_drvinfo = ntb_get_drvinfo,
306 	.get_link = ethtool_op_get_link,
307 	.get_settings = ntb_get_settings,
308 };
309 
310 static const struct ntb_queue_handlers ntb_netdev_handlers = {
311 	.tx_handler = ntb_netdev_tx_handler,
312 	.rx_handler = ntb_netdev_rx_handler,
313 	.event_handler = ntb_netdev_event_handler,
314 };
315 
316 static int ntb_netdev_probe(struct pci_dev *pdev)
317 {
318 	struct net_device *ndev;
319 	struct ntb_netdev *dev;
320 	int rc;
321 
322 	ndev = alloc_etherdev(sizeof(struct ntb_netdev));
323 	if (!ndev)
324 		return -ENOMEM;
325 
326 	dev = netdev_priv(ndev);
327 	dev->ndev = ndev;
328 	dev->pdev = pdev;
329 	BUG_ON(!dev->pdev);
330 	ndev->features = NETIF_F_HIGHDMA;
331 
332 	ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
333 
334 	ndev->hw_features = ndev->features;
335 	ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
336 
337 	random_ether_addr(ndev->perm_addr);
338 	memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
339 
340 	ndev->netdev_ops = &ntb_netdev_ops;
341 	SET_ETHTOOL_OPS(ndev, &ntb_ethtool_ops);
342 
343 	dev->qp = ntb_transport_create_queue(ndev, pdev, &ntb_netdev_handlers);
344 	if (!dev->qp) {
345 		rc = -EIO;
346 		goto err;
347 	}
348 
349 	ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
350 
351 	rc = register_netdev(ndev);
352 	if (rc)
353 		goto err1;
354 
355 	list_add(&dev->list, &dev_list);
356 	dev_info(&pdev->dev, "%s created\n", ndev->name);
357 	return 0;
358 
359 err1:
360 	ntb_transport_free_queue(dev->qp);
361 err:
362 	free_netdev(ndev);
363 	return rc;
364 }
365 
366 static void ntb_netdev_remove(struct pci_dev *pdev)
367 {
368 	struct net_device *ndev;
369 	struct ntb_netdev *dev;
370 
371 	list_for_each_entry(dev, &dev_list, list) {
372 		if (dev->pdev == pdev)
373 			break;
374 	}
375 	if (dev == NULL)
376 		return;
377 
378 	list_del(&dev->list);
379 
380 	ndev = dev->ndev;
381 
382 	unregister_netdev(ndev);
383 	ntb_transport_free_queue(dev->qp);
384 	free_netdev(ndev);
385 }
386 
387 static struct ntb_client ntb_netdev_client = {
388 	.driver.name = KBUILD_MODNAME,
389 	.driver.owner = THIS_MODULE,
390 	.probe = ntb_netdev_probe,
391 	.remove = ntb_netdev_remove,
392 };
393 
394 static int __init ntb_netdev_init_module(void)
395 {
396 	int rc;
397 
398 	rc = ntb_register_client_dev(KBUILD_MODNAME);
399 	if (rc)
400 		return rc;
401 	return ntb_register_client(&ntb_netdev_client);
402 }
403 module_init(ntb_netdev_init_module);
404 
405 static void __exit ntb_netdev_exit_module(void)
406 {
407 	ntb_unregister_client(&ntb_netdev_client);
408 	ntb_unregister_client_dev(KBUILD_MODNAME);
409 }
410 module_exit(ntb_netdev_exit_module);
411