net/hyperv: Remove unnecessary kmap_atomic in netvsc driver
[linux-2.6.git] / drivers / net / hyperv / netvsc_drv.c
1 /*
2  * Copyright (c) 2009, Microsoft Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15  * Place - Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Authors:
18  *   Haiyang Zhang <haiyangz@microsoft.com>
19  *   Hank Janssen  <hjanssen@microsoft.com>
20  */
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23 #include <linux/init.h>
24 #include <linux/atomic.h>
25 #include <linux/module.h>
26 #include <linux/highmem.h>
27 #include <linux/device.h>
28 #include <linux/io.h>
29 #include <linux/delay.h>
30 #include <linux/netdevice.h>
31 #include <linux/inetdevice.h>
32 #include <linux/etherdevice.h>
33 #include <linux/skbuff.h>
34 #include <linux/in.h>
35 #include <linux/slab.h>
36 #include <net/arp.h>
37 #include <net/route.h>
38 #include <net/sock.h>
39 #include <net/pkt_sched.h>
40
41 #include "hyperv_net.h"
42
43 struct net_device_context {
44         /* point back to our device context */
45         struct hv_device *device_ctx;
46         struct delayed_work dwork;
47 };
48
49
50 static int ring_size = 128;
51 module_param(ring_size, int, S_IRUGO);
52 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
53
54 struct set_multicast_work {
55         struct work_struct work;
56         struct net_device *net;
57 };
58
59 static void do_set_multicast(struct work_struct *w)
60 {
61         struct set_multicast_work *swk =
62                 container_of(w, struct set_multicast_work, work);
63         struct net_device *net = swk->net;
64
65         struct net_device_context *ndevctx = netdev_priv(net);
66         struct netvsc_device *nvdev;
67         struct rndis_device *rdev;
68
69         nvdev = hv_get_drvdata(ndevctx->device_ctx);
70         if (nvdev == NULL)
71                 return;
72
73         rdev = nvdev->extension;
74         if (rdev == NULL)
75                 return;
76
77         if (net->flags & IFF_PROMISC)
78                 rndis_filter_set_packet_filter(rdev,
79                         NDIS_PACKET_TYPE_PROMISCUOUS);
80         else
81                 rndis_filter_set_packet_filter(rdev,
82                         NDIS_PACKET_TYPE_BROADCAST |
83                         NDIS_PACKET_TYPE_ALL_MULTICAST |
84                         NDIS_PACKET_TYPE_DIRECTED);
85
86         kfree(w);
87 }
88
89 static void netvsc_set_multicast_list(struct net_device *net)
90 {
91         struct set_multicast_work *swk =
92                 kmalloc(sizeof(struct set_multicast_work), GFP_ATOMIC);
93         if (swk == NULL)
94                 return;
95
96         swk->net = net;
97         INIT_WORK(&swk->work, do_set_multicast);
98         schedule_work(&swk->work);
99 }
100
101 static int netvsc_open(struct net_device *net)
102 {
103         struct net_device_context *net_device_ctx = netdev_priv(net);
104         struct hv_device *device_obj = net_device_ctx->device_ctx;
105         int ret = 0;
106
107         /* Open up the device */
108         ret = rndis_filter_open(device_obj);
109         if (ret != 0) {
110                 netdev_err(net, "unable to open device (ret %d).\n", ret);
111                 return ret;
112         }
113
114         netif_start_queue(net);
115
116         return ret;
117 }
118
119 static int netvsc_close(struct net_device *net)
120 {
121         struct net_device_context *net_device_ctx = netdev_priv(net);
122         struct hv_device *device_obj = net_device_ctx->device_ctx;
123         int ret;
124
125         netif_stop_queue(net);
126
127         ret = rndis_filter_close(device_obj);
128         if (ret != 0)
129                 netdev_err(net, "unable to close device (ret %d).\n", ret);
130
131         return ret;
132 }
133
134 static void netvsc_xmit_completion(void *context)
135 {
136         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
137         struct sk_buff *skb = (struct sk_buff *)
138                 (unsigned long)packet->completion.send.send_completion_tid;
139
140         kfree(packet);
141
142         if (skb)
143                 dev_kfree_skb_any(skb);
144 }
145
146 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
147 {
148         struct net_device_context *net_device_ctx = netdev_priv(net);
149         struct hv_netvsc_packet *packet;
150         int ret;
151         unsigned int i, num_pages;
152
153         /* Add 1 for skb->data and additional one for RNDIS */
154         num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
155
156         /* Allocate a netvsc packet based on # of frags. */
157         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
158                          (num_pages * sizeof(struct hv_page_buffer)) +
159                          sizeof(struct rndis_filter_packet), GFP_ATOMIC);
160         if (!packet) {
161                 /* out of memory, drop packet */
162                 netdev_err(net, "unable to allocate hv_netvsc_packet\n");
163
164                 dev_kfree_skb(skb);
165                 net->stats.tx_dropped++;
166                 return NETDEV_TX_BUSY;
167         }
168
169         packet->extension = (void *)(unsigned long)packet +
170                                 sizeof(struct hv_netvsc_packet) +
171                                     (num_pages * sizeof(struct hv_page_buffer));
172
173         /* Setup the rndis header */
174         packet->page_buf_cnt = num_pages;
175
176         /* Initialize it from the skb */
177         packet->total_data_buflen       = skb->len;
178
179         /* Start filling in the page buffers starting after RNDIS buffer. */
180         packet->page_buf[1].pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
181         packet->page_buf[1].offset
182                 = (unsigned long)skb->data & (PAGE_SIZE - 1);
183         packet->page_buf[1].len = skb_headlen(skb);
184
185         /* Additional fragments are after SKB data */
186         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
187                 const skb_frag_t *f = &skb_shinfo(skb)->frags[i];
188
189                 packet->page_buf[i+2].pfn = page_to_pfn(skb_frag_page(f));
190                 packet->page_buf[i+2].offset = f->page_offset;
191                 packet->page_buf[i+2].len = skb_frag_size(f);
192         }
193
194         /* Set the completion routine */
195         packet->completion.send.send_completion = netvsc_xmit_completion;
196         packet->completion.send.send_completion_ctx = packet;
197         packet->completion.send.send_completion_tid = (unsigned long)skb;
198
199         ret = rndis_filter_send(net_device_ctx->device_ctx,
200                                   packet);
201         if (ret == 0) {
202                 net->stats.tx_bytes += skb->len;
203                 net->stats.tx_packets++;
204         } else {
205                 /* we are shutting down or bus overloaded, just drop packet */
206                 net->stats.tx_dropped++;
207                 kfree(packet);
208                 dev_kfree_skb_any(skb);
209         }
210
211         return ret ? NETDEV_TX_BUSY : NETDEV_TX_OK;
212 }
213
214 /*
215  * netvsc_linkstatus_callback - Link up/down notification
216  */
217 void netvsc_linkstatus_callback(struct hv_device *device_obj,
218                                        unsigned int status)
219 {
220         struct net_device *net;
221         struct net_device_context *ndev_ctx;
222         struct netvsc_device *net_device;
223
224         net_device = hv_get_drvdata(device_obj);
225         net = net_device->ndev;
226
227         if (!net) {
228                 netdev_err(net, "got link status but net device "
229                                 "not initialized yet\n");
230                 return;
231         }
232
233         if (status == 1) {
234                 netif_carrier_on(net);
235                 netif_wake_queue(net);
236                 ndev_ctx = netdev_priv(net);
237                 schedule_delayed_work(&ndev_ctx->dwork, 0);
238                 schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
239         } else {
240                 netif_carrier_off(net);
241                 netif_stop_queue(net);
242         }
243 }
244
245 /*
246  * netvsc_recv_callback -  Callback when we receive a packet from the
247  * "wire" on the specified device.
248  */
249 int netvsc_recv_callback(struct hv_device *device_obj,
250                                 struct hv_netvsc_packet *packet)
251 {
252         struct net_device *net = dev_get_drvdata(&device_obj->device);
253         struct sk_buff *skb;
254         struct netvsc_device *net_device;
255
256         net_device = hv_get_drvdata(device_obj);
257         net = net_device->ndev;
258
259         if (!net) {
260                 netdev_err(net, "got receive callback but net device"
261                         " not initialized yet\n");
262                 return 0;
263         }
264
265         /* Allocate a skb - TODO direct I/O to pages? */
266         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
267         if (unlikely(!skb)) {
268                 ++net->stats.rx_dropped;
269                 return 0;
270         }
271
272         /*
273          * Copy to skb. This copy is needed here since the memory pointed by
274          * hv_netvsc_packet cannot be deallocated
275          */
276         memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
277                 packet->total_data_buflen);
278
279         skb->protocol = eth_type_trans(skb, net);
280         skb->ip_summed = CHECKSUM_NONE;
281
282         net->stats.rx_packets++;
283         net->stats.rx_bytes += skb->len;
284
285         /*
286          * Pass the skb back up. Network stack will deallocate the skb when it
287          * is done.
288          * TODO - use NAPI?
289          */
290         netif_rx(skb);
291
292         return 0;
293 }
294
295 static void netvsc_get_drvinfo(struct net_device *net,
296                                struct ethtool_drvinfo *info)
297 {
298         strcpy(info->driver, "hv_netvsc");
299         strcpy(info->version, HV_DRV_VERSION);
300         strcpy(info->fw_version, "N/A");
301 }
302
303 static const struct ethtool_ops ethtool_ops = {
304         .get_drvinfo    = netvsc_get_drvinfo,
305         .get_link       = ethtool_op_get_link,
306 };
307
308 static const struct net_device_ops device_ops = {
309         .ndo_open =                     netvsc_open,
310         .ndo_stop =                     netvsc_close,
311         .ndo_start_xmit =               netvsc_start_xmit,
312         .ndo_set_rx_mode =              netvsc_set_multicast_list,
313         .ndo_change_mtu =               eth_change_mtu,
314         .ndo_validate_addr =            eth_validate_addr,
315         .ndo_set_mac_address =          eth_mac_addr,
316 };
317
318 /*
319  * Send GARP packet to network peers after migrations.
320  * After Quick Migration, the network is not immediately operational in the
321  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
322  * another netif_notify_peers() into a delayed work, otherwise GARP packet
323  * will not be sent after quick migration, and cause network disconnection.
324  */
325 static void netvsc_send_garp(struct work_struct *w)
326 {
327         struct net_device_context *ndev_ctx;
328         struct net_device *net;
329         struct netvsc_device *net_device;
330
331         ndev_ctx = container_of(w, struct net_device_context, dwork.work);
332         net_device = hv_get_drvdata(ndev_ctx->device_ctx);
333         net = net_device->ndev;
334         netif_notify_peers(net);
335 }
336
337
338 static int netvsc_probe(struct hv_device *dev,
339                         const struct hv_vmbus_device_id *dev_id)
340 {
341         struct net_device *net = NULL;
342         struct net_device_context *net_device_ctx;
343         struct netvsc_device_info device_info;
344         int ret;
345
346         net = alloc_etherdev(sizeof(struct net_device_context));
347         if (!net)
348                 return -ENOMEM;
349
350         /* Set initial state */
351         netif_carrier_off(net);
352
353         net_device_ctx = netdev_priv(net);
354         net_device_ctx->device_ctx = dev;
355         hv_set_drvdata(dev, net);
356         INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp);
357
358         net->netdev_ops = &device_ops;
359
360         /* TODO: Add GSO and Checksum offload */
361         net->hw_features = NETIF_F_SG;
362         net->features = NETIF_F_SG;
363
364         SET_ETHTOOL_OPS(net, &ethtool_ops);
365         SET_NETDEV_DEV(net, &dev->device);
366
367         ret = register_netdev(net);
368         if (ret != 0) {
369                 pr_err("Unable to register netdev.\n");
370                 free_netdev(net);
371                 goto out;
372         }
373
374         /* Notify the netvsc driver of the new device */
375         device_info.ring_size = ring_size;
376         ret = rndis_filter_device_add(dev, &device_info);
377         if (ret != 0) {
378                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
379                 unregister_netdev(net);
380                 free_netdev(net);
381                 hv_set_drvdata(dev, NULL);
382                 return ret;
383         }
384         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
385
386         netif_carrier_on(net);
387
388 out:
389         return ret;
390 }
391
392 static int netvsc_remove(struct hv_device *dev)
393 {
394         struct net_device *net;
395         struct net_device_context *ndev_ctx;
396         struct netvsc_device *net_device;
397
398         net_device = hv_get_drvdata(dev);
399         net = net_device->ndev;
400
401         if (net == NULL) {
402                 dev_err(&dev->device, "No net device to remove\n");
403                 return 0;
404         }
405
406         ndev_ctx = netdev_priv(net);
407         cancel_delayed_work_sync(&ndev_ctx->dwork);
408
409         /* Stop outbound asap */
410         netif_stop_queue(net);
411
412         unregister_netdev(net);
413
414         /*
415          * Call to the vsc driver to let it know that the device is being
416          * removed
417          */
418         rndis_filter_device_remove(dev);
419
420         free_netdev(net);
421         return 0;
422 }
423
424 static const struct hv_vmbus_device_id id_table[] = {
425         /* Network guid */
426         { VMBUS_DEVICE(0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
427                        0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E) },
428         { },
429 };
430
431 MODULE_DEVICE_TABLE(vmbus, id_table);
432
433 /* The one and only one */
434 static struct  hv_driver netvsc_drv = {
435         .name = "netvsc",
436         .id_table = id_table,
437         .probe = netvsc_probe,
438         .remove = netvsc_remove,
439 };
440
441 static void __exit netvsc_drv_exit(void)
442 {
443         vmbus_driver_unregister(&netvsc_drv);
444 }
445
446 static int __init netvsc_drv_init(void)
447 {
448         return vmbus_driver_register(&netvsc_drv);
449 }
450
451 MODULE_LICENSE("GPL");
452 MODULE_VERSION(HV_DRV_VERSION);
453 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
454
455 module_init(netvsc_drv_init);
456 module_exit(netvsc_drv_exit);