cd3eef04e59e123659e802ac72f38a6abb1c0a36
[pandora-kernel.git] / drivers / staging / hv / 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 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/highmem.h>
24 #include <linux/device.h>
25 #include <linux/io.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/inetdevice.h>
29 #include <linux/etherdevice.h>
30 #include <linux/skbuff.h>
31 #include <linux/in.h>
32 #include <linux/slab.h>
33 #include <linux/dmi.h>
34 #include <linux/pci.h>
35 #include <net/arp.h>
36 #include <net/route.h>
37 #include <net/sock.h>
38 #include <net/pkt_sched.h>
39 #include "osd.h"
40 #include "logging.h"
41 #include "version_info.h"
42 #include "vmbus.h"
43 #include "netvsc_api.h"
44
45 struct net_device_context {
46         /* point back to our device context */
47         struct vm_device *device_ctx;
48         unsigned long avail;
49 };
50
51 struct netvsc_driver_context {
52         /* !! These must be the first 2 fields !! */
53         /* Which is a bug FIXME! */
54         struct driver_context drv_ctx;
55         struct netvsc_driver drv_obj;
56 };
57
58 #define PACKET_PAGES_LOWATER  8
59 /* Need this many pages to handle worst case fragmented packet */
60 #define PACKET_PAGES_HIWATER  (MAX_SKB_FRAGS + 2)
61
62 static int ring_size = 128;
63 module_param(ring_size, int, S_IRUGO);
64 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
65
66 /* The one and only one */
67 static struct netvsc_driver_context g_netvsc_drv;
68
69 /* no-op so the netdev core doesn't return -EINVAL when modifying the the
70  * multicast address list in SIOCADDMULTI. hv is setup to get all multicast
71  * when it calls RndisFilterOnOpen() */
72 static void netvsc_set_multicast_list(struct net_device *net)
73 {
74 }
75
76 static int netvsc_open(struct net_device *net)
77 {
78         struct net_device_context *net_device_ctx = netdev_priv(net);
79         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
80         int ret = 0;
81
82         if (netif_carrier_ok(net)) {
83                 /* Open up the device */
84                 ret = RndisFilterOnOpen(device_obj);
85                 if (ret != 0) {
86                         DPRINT_ERR(NETVSC_DRV,
87                                    "unable to open device (ret %d).", ret);
88                         return ret;
89                 }
90
91                 netif_start_queue(net);
92         } else {
93                 DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
94         }
95
96         return ret;
97 }
98
99 static int netvsc_close(struct net_device *net)
100 {
101         struct net_device_context *net_device_ctx = netdev_priv(net);
102         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
103         int ret;
104
105         netif_stop_queue(net);
106
107         ret = RndisFilterOnClose(device_obj);
108         if (ret != 0)
109                 DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
110
111         return ret;
112 }
113
114 static void netvsc_xmit_completion(void *context)
115 {
116         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
117         struct sk_buff *skb = (struct sk_buff *)
118                 (unsigned long)packet->Completion.Send.SendCompletionTid;
119
120         kfree(packet);
121
122         if (skb) {
123                 struct net_device *net = skb->dev;
124                 struct net_device_context *net_device_ctx = netdev_priv(net);
125                 unsigned int num_pages = skb_shinfo(skb)->nr_frags + 2;
126
127                 dev_kfree_skb_any(skb);
128
129                 if ((net_device_ctx->avail += num_pages) >= PACKET_PAGES_HIWATER)
130                         netif_wake_queue(net);
131         }
132 }
133
134 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
135 {
136         struct net_device_context *net_device_ctx = netdev_priv(net);
137         struct driver_context *driver_ctx =
138             driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
139         struct netvsc_driver_context *net_drv_ctx =
140                 (struct netvsc_driver_context *)driver_ctx;
141         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
142         struct hv_netvsc_packet *packet;
143         int ret;
144         unsigned int i, num_pages;
145
146         DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d",
147                    skb->len, skb->data_len);
148
149         /* Add 1 for skb->data and additional one for RNDIS */
150         num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
151         if (num_pages > net_device_ctx->avail)
152                 return NETDEV_TX_BUSY;
153
154         /* Allocate a netvsc packet based on # of frags. */
155         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
156                          (num_pages * sizeof(struct hv_page_buffer)) +
157                          net_drv_obj->RequestExtSize, GFP_ATOMIC);
158         if (!packet) {
159                 /* out of memory, silently drop packet */
160                 DPRINT_ERR(NETVSC_DRV, "unable to allocate hv_netvsc_packet");
161
162                 dev_kfree_skb(skb);
163                 net->stats.tx_dropped++;
164                 return NETDEV_TX_OK;
165         }
166
167         packet->Extension = (void *)(unsigned long)packet +
168                                 sizeof(struct hv_netvsc_packet) +
169                                     (num_pages * sizeof(struct hv_page_buffer));
170
171         /* Setup the rndis header */
172         packet->PageBufferCount = num_pages;
173
174         /* TODO: Flush all write buffers/ memory fence ??? */
175         /* wmb(); */
176
177         /* Initialize it from the skb */
178         packet->TotalDataBufferLength   = skb->len;
179
180         /* Start filling in the page buffers starting after RNDIS buffer. */
181         packet->PageBuffers[1].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
182         packet->PageBuffers[1].Offset
183                 = (unsigned long)skb->data & (PAGE_SIZE - 1);
184         packet->PageBuffers[1].Length = skb_headlen(skb);
185
186         /* Additional fragments are after SKB data */
187         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
188                 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
189
190                 packet->PageBuffers[i+2].Pfn = page_to_pfn(f->page);
191                 packet->PageBuffers[i+2].Offset = f->page_offset;
192                 packet->PageBuffers[i+2].Length = f->size;
193         }
194
195         /* Set the completion routine */
196         packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
197         packet->Completion.Send.SendCompletionContext = packet;
198         packet->Completion.Send.SendCompletionTid = (unsigned long)skb;
199
200         ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj,
201                                   packet);
202         if (ret == 0) {
203                 net->stats.tx_bytes += skb->len;
204                 net->stats.tx_packets++;
205
206                 DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
207                            net->stats.tx_packets,
208                            net->stats.tx_bytes);
209
210                 if ((net_device_ctx->avail -= num_pages) < PACKET_PAGES_LOWATER)
211                         netif_stop_queue(net);
212         } else {
213                 /* we are shutting down or bus overloaded, just drop packet */
214                 net->stats.tx_dropped++;
215                 netvsc_xmit_completion(packet);
216         }
217
218         return NETDEV_TX_OK;
219 }
220
221 /*
222  * netvsc_linkstatus_callback - Link up/down notification
223  */
224 static void netvsc_linkstatus_callback(struct hv_device *device_obj,
225                                        unsigned int status)
226 {
227         struct vm_device *device_ctx = to_vm_device(device_obj);
228         struct net_device *net = dev_get_drvdata(&device_ctx->device);
229
230         if (!net) {
231                 DPRINT_ERR(NETVSC_DRV, "got link status but net device "
232                                 "not initialized yet");
233                 return;
234         }
235
236         if (status == 1) {
237                 netif_carrier_on(net);
238                 netif_wake_queue(net);
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 static int netvsc_recv_callback(struct hv_device *device_obj,
250                                 struct hv_netvsc_packet *packet)
251 {
252         struct vm_device *device_ctx = to_vm_device(device_obj);
253         struct net_device *net = dev_get_drvdata(&device_ctx->device);
254         struct sk_buff *skb;
255         void *data;
256         int i;
257         unsigned long flags;
258
259         if (!net) {
260                 DPRINT_ERR(NETVSC_DRV, "got receive callback but net device "
261                                 "not initialized yet");
262                 return 0;
263         }
264
265         /* Allocate a skb - TODO direct I/O to pages? */
266         skb = netdev_alloc_skb_ip_align(net, packet->TotalDataBufferLength);
267         if (unlikely(!skb)) {
268                 ++net->stats.rx_dropped;
269                 return 0;
270         }
271
272         /* for kmap_atomic */
273         local_irq_save(flags);
274
275         /*
276          * Copy to skb. This copy is needed here since the memory pointed by
277          * hv_netvsc_packet cannot be deallocated
278          */
279         for (i = 0; i < packet->PageBufferCount; i++) {
280                 data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn),
281                                                KM_IRQ1);
282                 data = (void *)(unsigned long)data +
283                                 packet->PageBuffers[i].Offset;
284
285                 memcpy(skb_put(skb, packet->PageBuffers[i].Length), data,
286                        packet->PageBuffers[i].Length);
287
288                 kunmap_atomic((void *)((unsigned long)data -
289                                        packet->PageBuffers[i].Offset), KM_IRQ1);
290         }
291
292         local_irq_restore(flags);
293
294         skb->protocol = eth_type_trans(skb, net);
295         skb->ip_summed = CHECKSUM_NONE;
296
297         net->stats.rx_packets++;
298         net->stats.rx_bytes += skb->len;
299
300         /*
301          * Pass the skb back up. Network stack will deallocate the skb when it
302          * is done.
303          * TODO - use NAPI?
304          */
305         netif_rx(skb);
306
307         DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
308                    net->stats.rx_packets, net->stats.rx_bytes);
309
310         return 0;
311 }
312
313 static void netvsc_get_drvinfo(struct net_device *net,
314                                struct ethtool_drvinfo *info)
315 {
316         strcpy(info->driver, "hv_netvsc");
317         strcpy(info->version, HV_DRV_VERSION);
318         strcpy(info->fw_version, "N/A");
319 }
320
321 static const struct ethtool_ops ethtool_ops = {
322         .get_drvinfo    = netvsc_get_drvinfo,
323         .get_sg         = ethtool_op_get_sg,
324         .set_sg         = ethtool_op_set_sg,
325         .get_link       = ethtool_op_get_link,
326 };
327
328 static const struct net_device_ops device_ops = {
329         .ndo_open =                     netvsc_open,
330         .ndo_stop =                     netvsc_close,
331         .ndo_start_xmit =               netvsc_start_xmit,
332         .ndo_set_multicast_list =       netvsc_set_multicast_list,
333         .ndo_change_mtu =               eth_change_mtu,
334         .ndo_validate_addr =            eth_validate_addr,
335         .ndo_set_mac_address =          eth_mac_addr,
336 };
337
338 static int netvsc_probe(struct device *device)
339 {
340         struct driver_context *driver_ctx =
341                 driver_to_driver_context(device->driver);
342         struct netvsc_driver_context *net_drv_ctx =
343                 (struct netvsc_driver_context *)driver_ctx;
344         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
345         struct vm_device *device_ctx = device_to_vm_device(device);
346         struct hv_device *device_obj = &device_ctx->device_obj;
347         struct net_device *net = NULL;
348         struct net_device_context *net_device_ctx;
349         struct netvsc_device_info device_info;
350         int ret;
351
352         if (!net_drv_obj->Base.OnDeviceAdd)
353                 return -1;
354
355         net = alloc_etherdev(sizeof(struct net_device_context));
356         if (!net)
357                 return -1;
358
359         /* Set initial state */
360         netif_carrier_off(net);
361         netif_stop_queue(net);
362
363         net_device_ctx = netdev_priv(net);
364         net_device_ctx->device_ctx = device_ctx;
365         net_device_ctx->avail = ring_size;
366         dev_set_drvdata(device, net);
367
368         /* Notify the netvsc driver of the new device */
369         ret = net_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
370         if (ret != 0) {
371                 free_netdev(net);
372                 dev_set_drvdata(device, NULL);
373
374                 DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)",
375                            ret);
376                 return ret;
377         }
378
379         /*
380          * If carrier is still off ie we did not get a link status callback,
381          * update it if necessary
382          */
383         /*
384          * FIXME: We should use a atomic or test/set instead to avoid getting
385          * out of sync with the device's link status
386          */
387         if (!netif_carrier_ok(net))
388                 if (!device_info.LinkState)
389                         netif_carrier_on(net);
390
391         memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);
392
393         net->netdev_ops = &device_ops;
394
395         /* TODO: Add GSO and Checksum offload */
396         net->features = NETIF_F_SG;
397
398         SET_ETHTOOL_OPS(net, &ethtool_ops);
399         SET_NETDEV_DEV(net, device);
400
401         ret = register_netdev(net);
402         if (ret != 0) {
403                 /* Remove the device and release the resource */
404                 net_drv_obj->Base.OnDeviceRemove(device_obj);
405                 free_netdev(net);
406         }
407
408         return ret;
409 }
410
411 static int netvsc_remove(struct device *device)
412 {
413         struct driver_context *driver_ctx =
414                 driver_to_driver_context(device->driver);
415         struct netvsc_driver_context *net_drv_ctx =
416                 (struct netvsc_driver_context *)driver_ctx;
417         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
418         struct vm_device *device_ctx = device_to_vm_device(device);
419         struct net_device *net = dev_get_drvdata(&device_ctx->device);
420         struct hv_device *device_obj = &device_ctx->device_obj;
421         int ret;
422
423         if (net == NULL) {
424                 DPRINT_INFO(NETVSC, "no net device to remove");
425                 return 0;
426         }
427
428         if (!net_drv_obj->Base.OnDeviceRemove)
429                 return -1;
430
431         /* Stop outbound asap */
432         netif_stop_queue(net);
433         /* netif_carrier_off(net); */
434
435         unregister_netdev(net);
436
437         /*
438          * Call to the vsc driver to let it know that the device is being
439          * removed
440          */
441         ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
442         if (ret != 0) {
443                 /* TODO: */
444                 DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
445         }
446
447         free_netdev(net);
448         return ret;
449 }
450
451 static int netvsc_drv_exit_cb(struct device *dev, void *data)
452 {
453         struct device **curr = (struct device **)data;
454
455         *curr = dev;
456         /* stop iterating */
457         return 1;
458 }
459
460 static void netvsc_drv_exit(void)
461 {
462         struct netvsc_driver *netvsc_drv_obj = &g_netvsc_drv.drv_obj;
463         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
464         struct device *current_dev;
465         int ret;
466
467         while (1) {
468                 current_dev = NULL;
469
470                 /* Get the device */
471                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
472                                              &current_dev, netvsc_drv_exit_cb);
473                 if (ret)
474                         DPRINT_WARN(NETVSC_DRV,
475                                     "driver_for_each_device returned %d", ret);
476
477                 if (current_dev == NULL)
478                         break;
479
480                 /* Initiate removal from the top-down */
481                 DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...",
482                             current_dev);
483
484                 device_unregister(current_dev);
485         }
486
487         if (netvsc_drv_obj->Base.OnCleanup)
488                 netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);
489
490         vmbus_child_driver_unregister(drv_ctx);
491
492         return;
493 }
494
495 static int netvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
496 {
497         struct netvsc_driver *net_drv_obj = &g_netvsc_drv.drv_obj;
498         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
499         int ret;
500
501         net_drv_obj->RingBufferSize = ring_size * PAGE_SIZE;
502         net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
503         net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;
504
505         /* Callback to client driver to complete the initialization */
506         drv_init(&net_drv_obj->Base);
507
508         drv_ctx->driver.name = net_drv_obj->Base.name;
509         memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType,
510                sizeof(struct hv_guid));
511
512         drv_ctx->probe = netvsc_probe;
513         drv_ctx->remove = netvsc_remove;
514
515         /* The driver belongs to vmbus */
516         ret = vmbus_child_driver_register(drv_ctx);
517
518         return ret;
519 }
520
521 static const struct dmi_system_id __initconst
522 hv_netvsc_dmi_table[] __maybe_unused  = {
523         {
524                 .ident = "Hyper-V",
525                 .matches = {
526                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
527                         DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
528                         DMI_MATCH(DMI_BOARD_NAME, "Virtual Machine"),
529                 },
530         },
531         { },
532 };
533 MODULE_DEVICE_TABLE(dmi, hv_netvsc_dmi_table);
534
535 static int __init netvsc_init(void)
536 {
537         DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
538
539         if (!dmi_check_system(hv_netvsc_dmi_table))
540                 return -ENODEV;
541
542         return netvsc_drv_init(netvsc_initialize);
543 }
544
545 static void __exit netvsc_exit(void)
546 {
547         netvsc_drv_exit();
548 }
549
550 static const struct pci_device_id __initconst
551 hv_netvsc_pci_table[] __maybe_unused = {
552         { PCI_DEVICE(0x1414, 0x5353) }, /* VGA compatible controller */
553         { 0 }
554 };
555 MODULE_DEVICE_TABLE(pci, hv_netvsc_pci_table);
556
557 MODULE_LICENSE("GPL");
558 MODULE_VERSION(HV_DRV_VERSION);
559 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
560
561 module_init(netvsc_init);
562 module_exit(netvsc_exit);