Staging: hv: check return value of driver_for_each_device()
[linux-2.6/mini2440.git] / drivers / staging / hv / netvsc_drv.c
blob9010f0e2ce680793bd715f60bb59decae51ed5f3
1 /*
3 * Copyright (c) 2009, Microsoft Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Authors:
19 * Hank Janssen <hjanssen@microsoft.com>
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/highmem.h>
26 #include <linux/device.h>
27 #include <linux/io.h>
28 #include <linux/delay.h>
29 #include <linux/netdevice.h>
30 #include <linux/inetdevice.h>
31 #include <linux/etherdevice.h>
32 #include <linux/skbuff.h>
33 #include <linux/in.h>
34 #include <net/arp.h>
35 #include <net/route.h>
36 #include <net/sock.h>
37 #include <net/pkt_sched.h>
39 #include "include/logging.h"
40 #include "include/vmbus.h"
42 #include "include/NetVscApi.h"
44 MODULE_LICENSE("GPL");
47 /* Static decl */
49 static int netvsc_probe(struct device *device);
50 static int netvsc_remove(struct device *device);
51 static int netvsc_open(struct net_device *net);
52 static void netvsc_xmit_completion(void *context);
53 static int netvsc_start_xmit (struct sk_buff *skb, struct net_device *net);
54 static int netvsc_recv_callback(struct hv_device *device_obj, NETVSC_PACKET* Packet);
55 static int netvsc_close(struct net_device *net);
56 static struct net_device_stats *netvsc_get_stats(struct net_device *net);
57 static void netvsc_linkstatus_callback(struct hv_device *device_obj, unsigned int status);
60 /* Data types */
62 struct net_device_context {
63 struct device_context *device_ctx; /* point back to our device context */
64 struct net_device_stats stats;
67 struct netvsc_driver_context {
68 /* !! These must be the first 2 fields !! */
69 struct driver_context drv_ctx;
70 NETVSC_DRIVER_OBJECT drv_obj;
74 /* Globals */
77 static int netvsc_ringbuffer_size = NETVSC_DEVICE_RING_BUFFER_SIZE;
79 /* The one and only one */
80 static struct netvsc_driver_context g_netvsc_drv;
83 /* Routines */
86 /*++
88 Name: netvsc_drv_init()
90 Desc: NetVsc driver initialization
92 --*/
93 int netvsc_drv_init(PFN_DRIVERINITIALIZE pfn_drv_init)
95 int ret=0;
96 NETVSC_DRIVER_OBJECT *net_drv_obj=&g_netvsc_drv.drv_obj;
97 struct driver_context *drv_ctx=&g_netvsc_drv.drv_ctx;
99 DPRINT_ENTER(NETVSC_DRV);
101 vmbus_get_interface(&net_drv_obj->Base.VmbusChannelInterface);
103 net_drv_obj->RingBufferSize = netvsc_ringbuffer_size;
104 net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
105 net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;
107 /* Callback to client driver to complete the initialization */
108 pfn_drv_init(&net_drv_obj->Base);
110 drv_ctx->driver.name = net_drv_obj->Base.name;
111 memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType, sizeof(GUID));
113 drv_ctx->probe = netvsc_probe;
114 drv_ctx->remove = netvsc_remove;
116 /* The driver belongs to vmbus */
117 ret = vmbus_child_driver_register(drv_ctx);
119 DPRINT_EXIT(NETVSC_DRV);
121 return ret;
124 /*++
126 Name: netvsc_get_stats()
128 Desc: Get the network stats
130 --*/
131 static struct net_device_stats *netvsc_get_stats(struct net_device *net)
133 struct net_device_context *net_device_ctx = netdev_priv(net);
135 return &net_device_ctx->stats;
138 /*++
140 Name: netvsc_set_multicast_list()
142 Desc: Set the multicast list
144 Remark: No-op here
145 --*/
146 static void netvsc_set_multicast_list(struct net_device *net)
151 static const struct net_device_ops device_ops = {
152 .ndo_open = netvsc_open,
153 .ndo_stop = netvsc_close,
154 .ndo_start_xmit = netvsc_start_xmit,
155 .ndo_get_stats = netvsc_get_stats,
156 .ndo_set_multicast_list = netvsc_set_multicast_list,
159 /*++
161 Name: netvsc_probe()
163 Desc: Add the specified new device to this driver
165 --*/
166 static int netvsc_probe(struct device *device)
168 int ret=0;
170 struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
171 struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
172 NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
174 struct device_context *device_ctx = device_to_device_context(device);
175 struct hv_device *device_obj = &device_ctx->device_obj;
177 struct net_device *net = NULL;
178 struct net_device_context *net_device_ctx;
179 NETVSC_DEVICE_INFO device_info;
181 DPRINT_ENTER(NETVSC_DRV);
183 if (!net_drv_obj->Base.OnDeviceAdd)
185 return -1;
188 net = alloc_netdev(sizeof(struct net_device_context), "seth%d", ether_setup);
189 /* net = alloc_etherdev(sizeof(struct net_device_context)); */
190 if (!net)
192 return -1;
195 /* Set initial state */
196 netif_carrier_off(net);
197 netif_stop_queue(net);
199 net_device_ctx = netdev_priv(net);
200 net_device_ctx->device_ctx = device_ctx;
201 dev_set_drvdata(device, net);
203 /* Notify the netvsc driver of the new device */
204 ret = net_drv_obj->Base.OnDeviceAdd(device_obj, (void*)&device_info);
205 if (ret != 0)
207 free_netdev(net);
208 dev_set_drvdata(device, NULL);
210 DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)", ret);
211 return ret;
214 /* If carrier is still off ie we did not get a link status callback, update it if necessary */
215 /* FIXME: We should use a atomic or test/set instead to avoid getting out of sync with the device's link status */
216 if (!netif_carrier_ok(net))
218 if (!device_info.LinkState)
220 netif_carrier_on(net);
224 memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);
226 net->netdev_ops = &device_ops;
228 SET_NETDEV_DEV(net, device);
230 ret = register_netdev(net);
231 if (ret != 0)
233 /* Remove the device and release the resource */
234 net_drv_obj->Base.OnDeviceRemove(device_obj);
235 free_netdev(net);
238 DPRINT_EXIT(NETVSC_DRV);
240 return ret;
243 static int netvsc_remove(struct device *device)
245 int ret=0;
246 struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
247 struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
248 NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
250 struct device_context *device_ctx = device_to_device_context(device);
251 struct net_device *net = dev_get_drvdata(&device_ctx->device);
252 struct hv_device *device_obj = &device_ctx->device_obj;
254 DPRINT_ENTER(NETVSC_DRV);
256 if (net == NULL)
258 DPRINT_INFO(NETVSC, "no net device to remove");
259 DPRINT_EXIT(NETVSC_DRV);
260 return 0;
263 if (!net_drv_obj->Base.OnDeviceRemove)
265 DPRINT_EXIT(NETVSC_DRV);
266 return -1;
269 /* Stop outbound asap */
270 netif_stop_queue(net);
271 /* netif_carrier_off(net); */
273 unregister_netdev(net);
275 /* Call to the vsc driver to let it know that the device is being removed */
276 ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
277 if (ret != 0)
279 /* TODO: */
280 DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
283 free_netdev(net);
285 DPRINT_EXIT(NETVSC_DRV);
287 return ret;
290 /*++
292 Name: netvsc_open()
294 Desc: Open the specified interface device
296 --*/
297 static int netvsc_open(struct net_device *net)
299 int ret=0;
300 struct net_device_context *net_device_ctx = netdev_priv(net);
301 struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
302 struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
303 NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
305 struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
307 DPRINT_ENTER(NETVSC_DRV);
309 if (netif_carrier_ok(net))
311 memset(&net_device_ctx->stats, 0 , sizeof(struct net_device_stats));
313 /* Open up the device */
314 ret = net_drv_obj->OnOpen(device_obj);
315 if (ret != 0)
317 DPRINT_ERR(NETVSC_DRV, "unable to open device (ret %d).", ret);
318 return ret;
321 netif_start_queue(net);
323 else
325 DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
328 DPRINT_EXIT(NETVSC_DRV);
329 return ret;
332 /*++
334 Name: netvsc_close()
336 Desc: Close the specified interface device
338 --*/
339 static int netvsc_close(struct net_device *net)
341 int ret=0;
342 struct net_device_context *net_device_ctx = netdev_priv(net);
343 struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
344 struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
345 NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
347 struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
349 DPRINT_ENTER(NETVSC_DRV);
351 netif_stop_queue(net);
353 ret = net_drv_obj->OnClose(device_obj);
354 if (ret != 0)
356 DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
359 DPRINT_EXIT(NETVSC_DRV);
361 return ret;
365 /*++
367 Name: netvsc_xmit_completion()
369 Desc: Send completion processing
371 --*/
372 static void netvsc_xmit_completion(void *context)
374 NETVSC_PACKET *packet = (NETVSC_PACKET *)context;
375 struct sk_buff *skb = (struct sk_buff *)(unsigned long)packet->Completion.Send.SendCompletionTid;
376 struct net_device* net;
378 DPRINT_ENTER(NETVSC_DRV);
380 kfree(packet);
382 if (skb)
384 net = skb->dev;
386 dev_kfree_skb_any(skb);
388 if (netif_queue_stopped(net))
390 DPRINT_INFO(NETVSC_DRV, "net device (%p) waking up...", net);
392 netif_wake_queue(net);
396 DPRINT_EXIT(NETVSC_DRV);
399 /*++
401 Name: netvsc_start_xmit()
403 Desc: Start a send
405 --*/
406 static int netvsc_start_xmit (struct sk_buff *skb, struct net_device *net)
408 int ret=0;
409 struct net_device_context *net_device_ctx = netdev_priv(net);
410 struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
411 struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
412 NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
414 int i=0;
415 NETVSC_PACKET* packet;
416 int num_frags;
417 int retries=0;
419 DPRINT_ENTER(NETVSC_DRV);
421 /* Support only 1 chain of frags */
422 ASSERT(skb_shinfo(skb)->frag_list == NULL);
423 ASSERT(skb->dev == net);
425 DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d", skb->len, skb->data_len);
427 /* Add 1 for skb->data and any additional ones requested */
428 num_frags = skb_shinfo(skb)->nr_frags + 1 + net_drv_obj->AdditionalRequestPageBufferCount;
430 /* Allocate a netvsc packet based on # of frags. */
431 packet = kzalloc(sizeof(NETVSC_PACKET) + (num_frags * sizeof(PAGE_BUFFER)) + net_drv_obj->RequestExtSize, GFP_ATOMIC);
432 if (!packet)
434 DPRINT_ERR(NETVSC_DRV, "unable to allocate NETVSC_PACKET");
435 return -1;
438 packet->Extension = (void*)(unsigned long)packet + sizeof(NETVSC_PACKET) + (num_frags * sizeof(PAGE_BUFFER)) ;
440 /* Setup the rndis header */
441 packet->PageBufferCount = num_frags;
443 /* TODO: Flush all write buffers/ memory fence ??? */
444 /* wmb(); */
446 /* Initialize it from the skb */
447 ASSERT(skb->data);
448 packet->TotalDataBufferLength = skb->len;
450 /* Start filling in the page buffers starting at AdditionalRequestPageBufferCount offset */
451 packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
452 packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Offset = (unsigned long)skb->data & (PAGE_SIZE -1);
453 packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Length = skb->len - skb->data_len;
455 ASSERT((skb->len - skb->data_len) <= PAGE_SIZE);
457 for (i=net_drv_obj->AdditionalRequestPageBufferCount+1; i<num_frags; i++)
459 packet->PageBuffers[i].Pfn = page_to_pfn(skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page);
460 packet->PageBuffers[i].Offset = skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page_offset;
461 packet->PageBuffers[i].Length = skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].size;
464 /* Set the completion routine */
465 packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
466 packet->Completion.Send.SendCompletionContext = packet;
467 packet->Completion.Send.SendCompletionTid = (unsigned long)skb;
469 retry_send:
470 ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj, packet);
472 if (ret == 0)
474 ret = NETDEV_TX_OK;
475 net_device_ctx->stats.tx_bytes += skb->len;
476 net_device_ctx->stats.tx_packets++;
478 else
480 retries++;
481 if (retries < 4)
483 DPRINT_ERR(NETVSC_DRV, "unable to send...retrying %d...", retries);
484 udelay(100);
485 goto retry_send;
488 /* no more room or we are shutting down */
489 DPRINT_ERR(NETVSC_DRV, "unable to send (%d)...marking net device (%p) busy", ret, net);
490 DPRINT_INFO(NETVSC_DRV, "net device (%p) stopping", net);
492 ret = NETDEV_TX_BUSY;
493 net_device_ctx->stats.tx_dropped++;
495 netif_stop_queue(net);
497 /* Null it since the caller will free it instead of the completion routine */
498 packet->Completion.Send.SendCompletionTid = 0;
500 /* Release the resources since we will not get any send completion */
501 netvsc_xmit_completion((void*)packet);
504 DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu", net_device_ctx->stats.tx_packets, net_device_ctx->stats.tx_bytes);
506 DPRINT_EXIT(NETVSC_DRV);
507 return ret;
511 /*++
513 Name: netvsc_linkstatus_callback()
515 Desc: Link up/down notification
517 --*/
518 static void netvsc_linkstatus_callback(struct hv_device *device_obj, unsigned int status)
520 struct device_context* device_ctx = to_device_context(device_obj);
521 struct net_device* net = dev_get_drvdata(&device_ctx->device);
523 DPRINT_ENTER(NETVSC_DRV);
525 if (!net)
527 DPRINT_ERR(NETVSC_DRV, "got link status but net device not initialized yet");
528 return;
531 if (status == 1)
533 netif_carrier_on(net);
534 netif_wake_queue(net);
536 else
538 netif_carrier_off(net);
539 netif_stop_queue(net);
541 DPRINT_EXIT(NETVSC_DRV);
545 /*++
547 Name: netvsc_recv_callback()
549 Desc: Callback when we receive a packet from the "wire" on the specify device
551 --*/
552 static int netvsc_recv_callback(struct hv_device *device_obj, NETVSC_PACKET* packet)
554 int ret=0;
555 struct device_context *device_ctx = to_device_context(device_obj);
556 struct net_device *net = dev_get_drvdata(&device_ctx->device);
557 struct net_device_context *net_device_ctx;
559 struct sk_buff *skb;
560 void *data;
561 int i=0;
562 unsigned long flags;
564 DPRINT_ENTER(NETVSC_DRV);
566 if (!net)
568 DPRINT_ERR(NETVSC_DRV, "got receive callback but net device not initialized yet");
569 return 0;
572 net_device_ctx = netdev_priv(net);
574 /* Allocate a skb - TODO preallocate this */
575 /* skb = alloc_skb(packet->TotalDataBufferLength, GFP_ATOMIC); */
576 skb = dev_alloc_skb(packet->TotalDataBufferLength + 2); /* Pad 2-bytes to align IP header to 16 bytes */
577 ASSERT(skb);
578 skb_reserve(skb, 2);
579 skb->dev = net;
581 /* for kmap_atomic */
582 local_irq_save(flags);
584 /* Copy to skb. This copy is needed here since the memory pointed by NETVSC_PACKET */
585 /* cannot be deallocated */
586 for (i=0; i<packet->PageBufferCount; i++)
588 data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn), KM_IRQ1);
589 data = (void*)(unsigned long)data + packet->PageBuffers[i].Offset;
591 memcpy(skb_put(skb, packet->PageBuffers[i].Length), data, packet->PageBuffers[i].Length);
593 kunmap_atomic((void*)((unsigned long)data - packet->PageBuffers[i].Offset), KM_IRQ1);
596 local_irq_restore(flags);
598 skb->protocol = eth_type_trans(skb, net);
600 skb->ip_summed = CHECKSUM_NONE;
602 /* Pass the skb back up. Network stack will deallocate the skb when it is done */
603 ret = netif_rx(skb);
605 switch (ret)
607 case NET_RX_DROP:
608 net_device_ctx->stats.rx_dropped++;
609 break;
610 default:
611 net_device_ctx->stats.rx_packets++;
612 net_device_ctx->stats.rx_bytes += skb->len;
613 break;
616 DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu", net_device_ctx->stats.rx_packets, net_device_ctx->stats.rx_bytes);
618 DPRINT_EXIT(NETVSC_DRV);
620 return 0;
623 static int netvsc_drv_exit_cb(struct device *dev, void *data)
625 struct device **curr = (struct device **)data;
626 *curr = dev;
627 return 1; /* stop iterating */
630 /*++
632 Name: netvsc_drv_exit()
634 Desc:
636 --*/
637 void netvsc_drv_exit(void)
639 NETVSC_DRIVER_OBJECT *netvsc_drv_obj=&g_netvsc_drv.drv_obj;
640 struct driver_context *drv_ctx=&g_netvsc_drv.drv_ctx;
641 struct device *current_dev=NULL;
642 int ret;
644 DPRINT_ENTER(NETVSC_DRV);
646 while (1)
648 current_dev = NULL;
650 /* Get the device */
651 ret = driver_for_each_device(&drv_ctx->driver, NULL,
652 (void *) &current_dev,
653 netvsc_drv_exit_cb);
655 if (ret)
656 DPRINT_WARN(NETVSC_DRV,
657 "driver_for_each_device returned %d", ret);
660 if (current_dev == NULL)
661 break;
663 /* Initiate removal from the top-down */
664 DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...", current_dev);
666 device_unregister(current_dev);
669 if (netvsc_drv_obj->Base.OnCleanup)
670 netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);
672 vmbus_child_driver_unregister(drv_ctx);
674 DPRINT_EXIT(NETVSC_DRV);
676 return;
679 static int __init netvsc_init(void)
681 int ret;
683 DPRINT_ENTER(NETVSC_DRV);
684 DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
686 ret = netvsc_drv_init(NetVscInitialize);
688 DPRINT_EXIT(NETVSC_DRV);
690 return ret;
693 static void __exit netvsc_exit(void)
695 DPRINT_ENTER(NETVSC_DRV);
697 netvsc_drv_exit();
699 DPRINT_EXIT(NETVSC_DRV);
702 module_param(netvsc_ringbuffer_size, int, S_IRUGO);
704 module_init(netvsc_init);
705 module_exit(netvsc_exit);