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Merge tag 'for-linus-20190706' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / net / hyperv / netvsc.c
blobd22a36fc7a7c62bd855e0f5b278d28b247f31be1
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2009, Microsoft Corporation.
4 *
5 * Authors:
6 * Haiyang Zhang <haiyangz@microsoft.com>
7 * Hank Janssen <hjanssen@microsoft.com>
8 */
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/wait.h>
14 #include <linux/mm.h>
15 #include <linux/delay.h>
16 #include <linux/io.h>
17 #include <linux/slab.h>
18 #include <linux/netdevice.h>
19 #include <linux/if_ether.h>
20 #include <linux/vmalloc.h>
21 #include <linux/rtnetlink.h>
22 #include <linux/prefetch.h>
23
24 #include <asm/sync_bitops.h>
25
26 #include "hyperv_net.h"
27 #include "netvsc_trace.h"
28
29 /*
30 * Switch the data path from the synthetic interface to the VF
31 * interface.
32 */
33 void netvsc_switch_datapath(struct net_device *ndev, bool vf)
34 {
35 struct net_device_context *net_device_ctx = netdev_priv(ndev);
36 struct hv_device *dev = net_device_ctx->device_ctx;
37 struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev);
38 struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;
39
40 memset(init_pkt, 0, sizeof(struct nvsp_message));
41 init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;
42 if (vf)
43 init_pkt->msg.v4_msg.active_dp.active_datapath =
44 NVSP_DATAPATH_VF;
45 else
46 init_pkt->msg.v4_msg.active_dp.active_datapath =
47 NVSP_DATAPATH_SYNTHETIC;
48
49 trace_nvsp_send(ndev, init_pkt);
50
51 vmbus_sendpacket(dev->channel, init_pkt,
52 sizeof(struct nvsp_message),
53 (unsigned long)init_pkt,
54 VM_PKT_DATA_INBAND, 0);
55 }
56
57 /* Worker to setup sub channels on initial setup
58 * Initial hotplug event occurs in softirq context
59 * and can't wait for channels.
60 */
61 static void netvsc_subchan_work(struct work_struct *w)
62 {
63 struct netvsc_device *nvdev =
64 container_of(w, struct netvsc_device, subchan_work);
65 struct rndis_device *rdev;
66 int i, ret;
67
68 /* Avoid deadlock with device removal already under RTNL */
69 if (!rtnl_trylock()) {
70 schedule_work(w);
71 return;
72 }
73
74 rdev = nvdev->extension;
75 if (rdev) {
76 ret = rndis_set_subchannel(rdev->ndev, nvdev, NULL);
77 if (ret == 0) {
78 netif_device_attach(rdev->ndev);
79 } else {
80 /* fallback to only primary channel */
81 for (i = 1; i < nvdev->num_chn; i++)
82 netif_napi_del(&nvdev->chan_table[i].napi);
83
84 nvdev->max_chn = 1;
85 nvdev->num_chn = 1;
86 }
87 }
88
89 rtnl_unlock();
90 }
91
92 static struct netvsc_device *alloc_net_device(void)
93 {
94 struct netvsc_device *net_device;
95
96 net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
97 if (!net_device)
98 return NULL;
99
100 init_waitqueue_head(&net_device->wait_drain);
101 net_device->destroy = false;
102 net_device->tx_disable = false;
103
104 net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
105 net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
106
107 init_completion(&net_device->channel_init_wait);
108 init_waitqueue_head(&net_device->subchan_open);
109 INIT_WORK(&net_device->subchan_work, netvsc_subchan_work);
110
111 return net_device;
112 }
113
114 static void free_netvsc_device(struct rcu_head *head)
115 {
116 struct netvsc_device *nvdev
117 = container_of(head, struct netvsc_device, rcu);
118 int i;
119
120 kfree(nvdev->extension);
121 vfree(nvdev->recv_buf);
122 vfree(nvdev->send_buf);
123 kfree(nvdev->send_section_map);
124
125 for (i = 0; i < VRSS_CHANNEL_MAX; i++)
126 vfree(nvdev->chan_table[i].mrc.slots);
127
128 kfree(nvdev);
129 }
130
131 static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
132 {
133 call_rcu(&nvdev->rcu, free_netvsc_device);
134 }
135
136 static void netvsc_revoke_recv_buf(struct hv_device *device,
137 struct netvsc_device *net_device,
138 struct net_device *ndev)
139 {
140 struct nvsp_message *revoke_packet;
141 int ret;
142
143 /*
144 * If we got a section count, it means we received a
145 * SendReceiveBufferComplete msg (ie sent
146 * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
147 * to send a revoke msg here
148 */
149 if (net_device->recv_section_cnt) {
150 /* Send the revoke receive buffer */
151 revoke_packet = &net_device->revoke_packet;
152 memset(revoke_packet, 0, sizeof(struct nvsp_message));
153
154 revoke_packet->hdr.msg_type =
155 NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
156 revoke_packet->msg.v1_msg.
157 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
158
159 trace_nvsp_send(ndev, revoke_packet);
160
161 ret = vmbus_sendpacket(device->channel,
162 revoke_packet,
163 sizeof(struct nvsp_message),
164 (unsigned long)revoke_packet,
165 VM_PKT_DATA_INBAND, 0);
166 /* If the failure is because the channel is rescinded;
167 * ignore the failure since we cannot send on a rescinded
168 * channel. This would allow us to properly cleanup
169 * even when the channel is rescinded.
170 */
171 if (device->channel->rescind)
172 ret = 0;
173 /*
174 * If we failed here, we might as well return and
175 * have a leak rather than continue and a bugchk
176 */
177 if (ret != 0) {
178 netdev_err(ndev, "unable to send "
179 "revoke receive buffer to netvsp\n");
180 return;
181 }
182 net_device->recv_section_cnt = 0;
183 }
184 }
185
186 static void netvsc_revoke_send_buf(struct hv_device *device,
187 struct netvsc_device *net_device,
188 struct net_device *ndev)
189 {
190 struct nvsp_message *revoke_packet;
191 int ret;
192
193 /* Deal with the send buffer we may have setup.
194 * If we got a send section size, it means we received a
195 * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
196 * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
197 * to send a revoke msg here
198 */
199 if (net_device->send_section_cnt) {
200 /* Send the revoke receive buffer */
201 revoke_packet = &net_device->revoke_packet;
202 memset(revoke_packet, 0, sizeof(struct nvsp_message));
203
204 revoke_packet->hdr.msg_type =
205 NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
206 revoke_packet->msg.v1_msg.revoke_send_buf.id =
207 NETVSC_SEND_BUFFER_ID;
208
209 trace_nvsp_send(ndev, revoke_packet);
210
211 ret = vmbus_sendpacket(device->channel,
212 revoke_packet,
213 sizeof(struct nvsp_message),
214 (unsigned long)revoke_packet,
215 VM_PKT_DATA_INBAND, 0);
216
217 /* If the failure is because the channel is rescinded;
218 * ignore the failure since we cannot send on a rescinded
219 * channel. This would allow us to properly cleanup
220 * even when the channel is rescinded.
221 */
222 if (device->channel->rescind)
223 ret = 0;
224
225 /* If we failed here, we might as well return and
226 * have a leak rather than continue and a bugchk
227 */
228 if (ret != 0) {
229 netdev_err(ndev, "unable to send "
230 "revoke send buffer to netvsp\n");
231 return;
232 }
233 net_device->send_section_cnt = 0;
234 }
235 }
236
237 static void netvsc_teardown_recv_gpadl(struct hv_device *device,
238 struct netvsc_device *net_device,
239 struct net_device *ndev)
240 {
241 int ret;
242
243 if (net_device->recv_buf_gpadl_handle) {
244 ret = vmbus_teardown_gpadl(device->channel,
245 net_device->recv_buf_gpadl_handle);
246
247 /* If we failed here, we might as well return and have a leak
248 * rather than continue and a bugchk
249 */
250 if (ret != 0) {
251 netdev_err(ndev,
252 "unable to teardown receive buffer's gpadl\n");
253 return;
254 }
255 net_device->recv_buf_gpadl_handle = 0;
256 }
257 }
258
259 static void netvsc_teardown_send_gpadl(struct hv_device *device,
260 struct netvsc_device *net_device,
261 struct net_device *ndev)
262 {
263 int ret;
264
265 if (net_device->send_buf_gpadl_handle) {
266 ret = vmbus_teardown_gpadl(device->channel,
267 net_device->send_buf_gpadl_handle);
268
269 /* If we failed here, we might as well return and have a leak
270 * rather than continue and a bugchk
271 */
272 if (ret != 0) {
273 netdev_err(ndev,
274 "unable to teardown send buffer's gpadl\n");
275 return;
276 }
277 net_device->send_buf_gpadl_handle = 0;
278 }
279 }
280
281 int netvsc_alloc_recv_comp_ring(struct netvsc_device *net_device, u32 q_idx)
282 {
283 struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
284 int node = cpu_to_node(nvchan->channel->target_cpu);
285 size_t size;
286
287 size = net_device->recv_completion_cnt * sizeof(struct recv_comp_data);
288 nvchan->mrc.slots = vzalloc_node(size, node);
289 if (!nvchan->mrc.slots)
290 nvchan->mrc.slots = vzalloc(size);
291
292 return nvchan->mrc.slots ? 0 : -ENOMEM;
293 }
294
295 static int netvsc_init_buf(struct hv_device *device,
296 struct netvsc_device *net_device,
297 const struct netvsc_device_info *device_info)
298 {
299 struct nvsp_1_message_send_receive_buffer_complete *resp;
300 struct net_device *ndev = hv_get_drvdata(device);
301 struct nvsp_message *init_packet;
302 unsigned int buf_size;
303 size_t map_words;
304 int ret = 0;
305
306 /* Get receive buffer area. */
307 buf_size = device_info->recv_sections * device_info->recv_section_size;
308 buf_size = roundup(buf_size, PAGE_SIZE);
309
310 /* Legacy hosts only allow smaller receive buffer */
311 if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
312 buf_size = min_t(unsigned int, buf_size,
313 NETVSC_RECEIVE_BUFFER_SIZE_LEGACY);
314
315 net_device->recv_buf = vzalloc(buf_size);
316 if (!net_device->recv_buf) {
317 netdev_err(ndev,
318 "unable to allocate receive buffer of size %u\n",
319 buf_size);
320 ret = -ENOMEM;
321 goto cleanup;
322 }
323
324 net_device->recv_buf_size = buf_size;
325
326 /*
327 * Establish the gpadl handle for this buffer on this
328 * channel. Note: This call uses the vmbus connection rather
329 * than the channel to establish the gpadl handle.
330 */
331 ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
332 buf_size,
333 &net_device->recv_buf_gpadl_handle);
334 if (ret != 0) {
335 netdev_err(ndev,
336 "unable to establish receive buffer's gpadl\n");
337 goto cleanup;
338 }
339
340 /* Notify the NetVsp of the gpadl handle */
341 init_packet = &net_device->channel_init_pkt;
342 memset(init_packet, 0, sizeof(struct nvsp_message));
343 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
344 init_packet->msg.v1_msg.send_recv_buf.
345 gpadl_handle = net_device->recv_buf_gpadl_handle;
346 init_packet->msg.v1_msg.
347 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
348
349 trace_nvsp_send(ndev, init_packet);
350
351 /* Send the gpadl notification request */
352 ret = vmbus_sendpacket(device->channel, init_packet,
353 sizeof(struct nvsp_message),
354 (unsigned long)init_packet,
355 VM_PKT_DATA_INBAND,
356 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
357 if (ret != 0) {
358 netdev_err(ndev,
359 "unable to send receive buffer's gpadl to netvsp\n");
360 goto cleanup;
361 }
362
363 wait_for_completion(&net_device->channel_init_wait);
364
365 /* Check the response */
366 resp = &init_packet->msg.v1_msg.send_recv_buf_complete;
367 if (resp->status != NVSP_STAT_SUCCESS) {
368 netdev_err(ndev,
369 "Unable to complete receive buffer initialization with NetVsp - status %d\n",
370 resp->status);
371 ret = -EINVAL;
372 goto cleanup;
373 }
374
375 /* Parse the response */
376 netdev_dbg(ndev, "Receive sections: %u sub_allocs: size %u count: %u\n",
377 resp->num_sections, resp->sections[0].sub_alloc_size,
378 resp->sections[0].num_sub_allocs);
379
380 /* There should only be one section for the entire receive buffer */
381 if (resp->num_sections != 1 || resp->sections[0].offset != 0) {
382 ret = -EINVAL;
383 goto cleanup;
384 }
385
386 net_device->recv_section_size = resp->sections[0].sub_alloc_size;
387 net_device->recv_section_cnt = resp->sections[0].num_sub_allocs;
388
389 /* Setup receive completion ring */
390 net_device->recv_completion_cnt
391 = round_up(net_device->recv_section_cnt + 1,
392 PAGE_SIZE / sizeof(u64));
393 ret = netvsc_alloc_recv_comp_ring(net_device, 0);
394 if (ret)
395 goto cleanup;
396
397 /* Now setup the send buffer. */
398 buf_size = device_info->send_sections * device_info->send_section_size;
399 buf_size = round_up(buf_size, PAGE_SIZE);
400
401 net_device->send_buf = vzalloc(buf_size);
402 if (!net_device->send_buf) {
403 netdev_err(ndev, "unable to allocate send buffer of size %u\n",
404 buf_size);
405 ret = -ENOMEM;
406 goto cleanup;
407 }
408
409 /* Establish the gpadl handle for this buffer on this
410 * channel. Note: This call uses the vmbus connection rather
411 * than the channel to establish the gpadl handle.
412 */
413 ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
414 buf_size,
415 &net_device->send_buf_gpadl_handle);
416 if (ret != 0) {
417 netdev_err(ndev,
418 "unable to establish send buffer's gpadl\n");
419 goto cleanup;
420 }
421
422 /* Notify the NetVsp of the gpadl handle */
423 init_packet = &net_device->channel_init_pkt;
424 memset(init_packet, 0, sizeof(struct nvsp_message));
425 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
426 init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
427 net_device->send_buf_gpadl_handle;
428 init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
429
430 trace_nvsp_send(ndev, init_packet);
431
432 /* Send the gpadl notification request */
433 ret = vmbus_sendpacket(device->channel, init_packet,
434 sizeof(struct nvsp_message),
435 (unsigned long)init_packet,
436 VM_PKT_DATA_INBAND,
437 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
438 if (ret != 0) {
439 netdev_err(ndev,
440 "unable to send send buffer's gpadl to netvsp\n");
441 goto cleanup;
442 }
443
444 wait_for_completion(&net_device->channel_init_wait);
445
446 /* Check the response */
447 if (init_packet->msg.v1_msg.
448 send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
449 netdev_err(ndev, "Unable to complete send buffer "
450 "initialization with NetVsp - status %d\n",
451 init_packet->msg.v1_msg.
452 send_send_buf_complete.status);
453 ret = -EINVAL;
454 goto cleanup;
455 }
456
457 /* Parse the response */
458 net_device->send_section_size = init_packet->msg.
459 v1_msg.send_send_buf_complete.section_size;
460
461 /* Section count is simply the size divided by the section size. */
462 net_device->send_section_cnt = buf_size / net_device->send_section_size;
463
464 netdev_dbg(ndev, "Send section size: %d, Section count:%d\n",
465 net_device->send_section_size, net_device->send_section_cnt);
466
467 /* Setup state for managing the send buffer. */
468 map_words = DIV_ROUND_UP(net_device->send_section_cnt, BITS_PER_LONG);
469
470 net_device->send_section_map = kcalloc(map_words, sizeof(ulong), GFP_KERNEL);
471 if (net_device->send_section_map == NULL) {
472 ret = -ENOMEM;
473 goto cleanup;
474 }
475
476 goto exit;
477
478 cleanup:
479 netvsc_revoke_recv_buf(device, net_device, ndev);
480 netvsc_revoke_send_buf(device, net_device, ndev);
481 netvsc_teardown_recv_gpadl(device, net_device, ndev);
482 netvsc_teardown_send_gpadl(device, net_device, ndev);
483
484 exit:
485 return ret;
486 }
487
488 /* Negotiate NVSP protocol version */
489 static int negotiate_nvsp_ver(struct hv_device *device,
490 struct netvsc_device *net_device,
491 struct nvsp_message *init_packet,
492 u32 nvsp_ver)
493 {
494 struct net_device *ndev = hv_get_drvdata(device);
495 int ret;
496
497 memset(init_packet, 0, sizeof(struct nvsp_message));
498 init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
499 init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
500 init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
501 trace_nvsp_send(ndev, init_packet);
502
503 /* Send the init request */
504 ret = vmbus_sendpacket(device->channel, init_packet,
505 sizeof(struct nvsp_message),
506 (unsigned long)init_packet,
507 VM_PKT_DATA_INBAND,
508 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
509
510 if (ret != 0)
511 return ret;
512
513 wait_for_completion(&net_device->channel_init_wait);
514
515 if (init_packet->msg.init_msg.init_complete.status !=
516 NVSP_STAT_SUCCESS)
517 return -EINVAL;
518
519 if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
520 return 0;
521
522 /* NVSPv2 or later: Send NDIS config */
523 memset(init_packet, 0, sizeof(struct nvsp_message));
524 init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
525 init_packet->msg.v2_msg.send_ndis_config.mtu = ndev->mtu + ETH_HLEN;
526 init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
527
528 if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
529 init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
530
531 /* Teaming bit is needed to receive link speed updates */
532 init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
533 }
534
535 if (nvsp_ver >= NVSP_PROTOCOL_VERSION_61)
536 init_packet->msg.v2_msg.send_ndis_config.capability.rsc = 1;
537
538 trace_nvsp_send(ndev, init_packet);
539
540 ret = vmbus_sendpacket(device->channel, init_packet,
541 sizeof(struct nvsp_message),
542 (unsigned long)init_packet,
543 VM_PKT_DATA_INBAND, 0);
544
545 return ret;
546 }
547
548 static int netvsc_connect_vsp(struct hv_device *device,
549 struct netvsc_device *net_device,
550 const struct netvsc_device_info *device_info)
551 {
552 struct net_device *ndev = hv_get_drvdata(device);
553 static const u32 ver_list[] = {
554 NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
555 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5,
556 NVSP_PROTOCOL_VERSION_6, NVSP_PROTOCOL_VERSION_61
557 };
558 struct nvsp_message *init_packet;
559 int ndis_version, i, ret;
560
561 init_packet = &net_device->channel_init_pkt;
562
563 /* Negotiate the latest NVSP protocol supported */
564 for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
565 if (negotiate_nvsp_ver(device, net_device, init_packet,
566 ver_list[i]) == 0) {
567 net_device->nvsp_version = ver_list[i];
568 break;
569 }
570
571 if (i < 0) {
572 ret = -EPROTO;
573 goto cleanup;
574 }
575
576 pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
577
578 /* Send the ndis version */
579 memset(init_packet, 0, sizeof(struct nvsp_message));
580
581 if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
582 ndis_version = 0x00060001;
583 else
584 ndis_version = 0x0006001e;
585
586 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
587 init_packet->msg.v1_msg.
588 send_ndis_ver.ndis_major_ver =
589 (ndis_version & 0xFFFF0000) >> 16;
590 init_packet->msg.v1_msg.
591 send_ndis_ver.ndis_minor_ver =
592 ndis_version & 0xFFFF;
593
594 trace_nvsp_send(ndev, init_packet);
595
596 /* Send the init request */
597 ret = vmbus_sendpacket(device->channel, init_packet,
598 sizeof(struct nvsp_message),
599 (unsigned long)init_packet,
600 VM_PKT_DATA_INBAND, 0);
601 if (ret != 0)
602 goto cleanup;
603
604
605 ret = netvsc_init_buf(device, net_device, device_info);
606
607 cleanup:
608 return ret;
609 }
610
611 /*
612 * netvsc_device_remove - Callback when the root bus device is removed
613 */
614 void netvsc_device_remove(struct hv_device *device)
615 {
616 struct net_device *ndev = hv_get_drvdata(device);
617 struct net_device_context *net_device_ctx = netdev_priv(ndev);
618 struct netvsc_device *net_device
619 = rtnl_dereference(net_device_ctx->nvdev);
620 int i;
621
622 /*
623 * Revoke receive buffer. If host is pre-Win2016 then tear down
624 * receive buffer GPADL. Do the same for send buffer.
625 */
626 netvsc_revoke_recv_buf(device, net_device, ndev);
627 if (vmbus_proto_version < VERSION_WIN10)
628 netvsc_teardown_recv_gpadl(device, net_device, ndev);
629
630 netvsc_revoke_send_buf(device, net_device, ndev);
631 if (vmbus_proto_version < VERSION_WIN10)
632 netvsc_teardown_send_gpadl(device, net_device, ndev);
633
634 RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
635
636 /* And disassociate NAPI context from device */
637 for (i = 0; i < net_device->num_chn; i++)
638 netif_napi_del(&net_device->chan_table[i].napi);
639
640 /*
641 * At this point, no one should be accessing net_device
642 * except in here
643 */
644 netdev_dbg(ndev, "net device safe to remove\n");
645
646 /* Now, we can close the channel safely */
647 vmbus_close(device->channel);
648
649 /*
650 * If host is Win2016 or higher then we do the GPADL tear down
651 * here after VMBus is closed.
652 */
653 if (vmbus_proto_version >= VERSION_WIN10) {
654 netvsc_teardown_recv_gpadl(device, net_device, ndev);
655 netvsc_teardown_send_gpadl(device, net_device, ndev);
656 }
657
658 /* Release all resources */
659 free_netvsc_device_rcu(net_device);
660 }
661
662 #define RING_AVAIL_PERCENT_HIWATER 20
663 #define RING_AVAIL_PERCENT_LOWATER 10
664
665 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
666 u32 index)
667 {
668 sync_change_bit(index, net_device->send_section_map);
669 }
670
671 static void netvsc_send_tx_complete(struct net_device *ndev,
672 struct netvsc_device *net_device,
673 struct vmbus_channel *channel,
674 const struct vmpacket_descriptor *desc,
675 int budget)
676 {
677 struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
678 struct net_device_context *ndev_ctx = netdev_priv(ndev);
679 u16 q_idx = 0;
680 int queue_sends;
681
682 /* Notify the layer above us */
683 if (likely(skb)) {
684 const struct hv_netvsc_packet *packet
685 = (struct hv_netvsc_packet *)skb->cb;
686 u32 send_index = packet->send_buf_index;
687 struct netvsc_stats *tx_stats;
688
689 if (send_index != NETVSC_INVALID_INDEX)
690 netvsc_free_send_slot(net_device, send_index);
691 q_idx = packet->q_idx;
692
693 tx_stats = &net_device->chan_table[q_idx].tx_stats;
694
695 u64_stats_update_begin(&tx_stats->syncp);
696 tx_stats->packets += packet->total_packets;
697 tx_stats->bytes += packet->total_bytes;
698 u64_stats_update_end(&tx_stats->syncp);
699
700 napi_consume_skb(skb, budget);
701 }
702
703 queue_sends =
704 atomic_dec_return(&net_device->chan_table[q_idx].queue_sends);
705
706 if (unlikely(net_device->destroy)) {
707 if (queue_sends == 0)
708 wake_up(&net_device->wait_drain);
709 } else {
710 struct netdev_queue *txq = netdev_get_tx_queue(ndev, q_idx);
711
712 if (netif_tx_queue_stopped(txq) && !net_device->tx_disable &&
713 (hv_get_avail_to_write_percent(&channel->outbound) >
714 RING_AVAIL_PERCENT_HIWATER || queue_sends < 1)) {
715 netif_tx_wake_queue(txq);
716 ndev_ctx->eth_stats.wake_queue++;
717 }
718 }
719 }
720
721 static void netvsc_send_completion(struct net_device *ndev,
722 struct netvsc_device *net_device,
723 struct vmbus_channel *incoming_channel,
724 const struct vmpacket_descriptor *desc,
725 int budget)
726 {
727 const struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
728
729 switch (nvsp_packet->hdr.msg_type) {
730 case NVSP_MSG_TYPE_INIT_COMPLETE:
731 case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
732 case NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE:
733 case NVSP_MSG5_TYPE_SUBCHANNEL:
734 /* Copy the response back */
735 memcpy(&net_device->channel_init_pkt, nvsp_packet,
736 sizeof(struct nvsp_message));
737 complete(&net_device->channel_init_wait);
738 break;
739
740 case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
741 netvsc_send_tx_complete(ndev, net_device, incoming_channel,
742 desc, budget);
743 break;
744
745 default:
746 netdev_err(ndev,
747 "Unknown send completion type %d received!!\n",
748 nvsp_packet->hdr.msg_type);
749 }
750 }
751
752 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
753 {
754 unsigned long *map_addr = net_device->send_section_map;
755 unsigned int i;
756
757 for_each_clear_bit(i, map_addr, net_device->send_section_cnt) {
758 if (sync_test_and_set_bit(i, map_addr) == 0)
759 return i;
760 }
761
762 return NETVSC_INVALID_INDEX;
763 }
764
765 static void netvsc_copy_to_send_buf(struct netvsc_device *net_device,
766 unsigned int section_index,
767 u32 pend_size,
768 struct hv_netvsc_packet *packet,
769 struct rndis_message *rndis_msg,
770 struct hv_page_buffer *pb,
771 bool xmit_more)
772 {
773 char *start = net_device->send_buf;
774 char *dest = start + (section_index * net_device->send_section_size)
775 + pend_size;
776 int i;
777 u32 padding = 0;
778 u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
779 packet->page_buf_cnt;
780 u32 remain;
781
782 /* Add padding */
783 remain = packet->total_data_buflen & (net_device->pkt_align - 1);
784 if (xmit_more && remain) {
785 padding = net_device->pkt_align - remain;
786 rndis_msg->msg_len += padding;
787 packet->total_data_buflen += padding;
788 }
789
790 for (i = 0; i < page_count; i++) {
791 char *src = phys_to_virt(pb[i].pfn << PAGE_SHIFT);
792 u32 offset = pb[i].offset;
793 u32 len = pb[i].len;
794
795 memcpy(dest, (src + offset), len);
796 dest += len;
797 }
798
799 if (padding)
800 memset(dest, 0, padding);
801 }
802
803 static inline int netvsc_send_pkt(
804 struct hv_device *device,
805 struct hv_netvsc_packet *packet,
806 struct netvsc_device *net_device,
807 struct hv_page_buffer *pb,
808 struct sk_buff *skb)
809 {
810 struct nvsp_message nvmsg;
811 struct nvsp_1_message_send_rndis_packet *rpkt =
812 &nvmsg.msg.v1_msg.send_rndis_pkt;
813 struct netvsc_channel * const nvchan =
814 &net_device->chan_table[packet->q_idx];
815 struct vmbus_channel *out_channel = nvchan->channel;
816 struct net_device *ndev = hv_get_drvdata(device);
817 struct net_device_context *ndev_ctx = netdev_priv(ndev);
818 struct netdev_queue *txq = netdev_get_tx_queue(ndev, packet->q_idx);
819 u64 req_id;
820 int ret;
821 u32 ring_avail = hv_get_avail_to_write_percent(&out_channel->outbound);
822
823 nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
824 if (skb)
825 rpkt->channel_type = 0; /* 0 is RMC_DATA */
826 else
827 rpkt->channel_type = 1; /* 1 is RMC_CONTROL */
828
829 rpkt->send_buf_section_index = packet->send_buf_index;
830 if (packet->send_buf_index == NETVSC_INVALID_INDEX)
831 rpkt->send_buf_section_size = 0;
832 else
833 rpkt->send_buf_section_size = packet->total_data_buflen;
834
835 req_id = (ulong)skb;
836
837 if (out_channel->rescind)
838 return -ENODEV;
839
840 trace_nvsp_send_pkt(ndev, out_channel, rpkt);
841
842 if (packet->page_buf_cnt) {
843 if (packet->cp_partial)
844 pb += packet->rmsg_pgcnt;
845
846 ret = vmbus_sendpacket_pagebuffer(out_channel,
847 pb, packet->page_buf_cnt,
848 &nvmsg, sizeof(nvmsg),
849 req_id);
850 } else {
851 ret = vmbus_sendpacket(out_channel,
852 &nvmsg, sizeof(nvmsg),
853 req_id, VM_PKT_DATA_INBAND,
854 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
855 }
856
857 if (ret == 0) {
858 atomic_inc_return(&nvchan->queue_sends);
859
860 if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
861 netif_tx_stop_queue(txq);
862 ndev_ctx->eth_stats.stop_queue++;
863 }
864 } else if (ret == -EAGAIN) {
865 netif_tx_stop_queue(txq);
866 ndev_ctx->eth_stats.stop_queue++;
867 } else {
868 netdev_err(ndev,
869 "Unable to send packet pages %u len %u, ret %d\n",
870 packet->page_buf_cnt, packet->total_data_buflen,
871 ret);
872 }
873
874 if (netif_tx_queue_stopped(txq) &&
875 atomic_read(&nvchan->queue_sends) < 1 &&
876 !net_device->tx_disable) {
877 netif_tx_wake_queue(txq);
878 ndev_ctx->eth_stats.wake_queue++;
879 if (ret == -EAGAIN)
880 ret = -ENOSPC;
881 }
882
883 return ret;
884 }
885
886 /* Move packet out of multi send data (msd), and clear msd */
887 static inline void move_pkt_msd(struct hv_netvsc_packet **msd_send,
888 struct sk_buff **msd_skb,
889 struct multi_send_data *msdp)
890 {
891 *msd_skb = msdp->skb;
892 *msd_send = msdp->pkt;
893 msdp->skb = NULL;
894 msdp->pkt = NULL;
895 msdp->count = 0;
896 }
897
898 /* RCU already held by caller */
899 int netvsc_send(struct net_device *ndev,
900 struct hv_netvsc_packet *packet,
901 struct rndis_message *rndis_msg,
902 struct hv_page_buffer *pb,
903 struct sk_buff *skb)
904 {
905 struct net_device_context *ndev_ctx = netdev_priv(ndev);
906 struct netvsc_device *net_device
907 = rcu_dereference_bh(ndev_ctx->nvdev);
908 struct hv_device *device = ndev_ctx->device_ctx;
909 int ret = 0;
910 struct netvsc_channel *nvchan;
911 u32 pktlen = packet->total_data_buflen, msd_len = 0;
912 unsigned int section_index = NETVSC_INVALID_INDEX;
913 struct multi_send_data *msdp;
914 struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
915 struct sk_buff *msd_skb = NULL;
916 bool try_batch, xmit_more;
917
918 /* If device is rescinded, return error and packet will get dropped. */
919 if (unlikely(!net_device || net_device->destroy))
920 return -ENODEV;
921
922 nvchan = &net_device->chan_table[packet->q_idx];
923 packet->send_buf_index = NETVSC_INVALID_INDEX;
924 packet->cp_partial = false;
925
926 /* Send control message directly without accessing msd (Multi-Send
927 * Data) field which may be changed during data packet processing.
928 */
929 if (!skb)
930 return netvsc_send_pkt(device, packet, net_device, pb, skb);
931
932 /* batch packets in send buffer if possible */
933 msdp = &nvchan->msd;
934 if (msdp->pkt)
935 msd_len = msdp->pkt->total_data_buflen;
936
937 try_batch = msd_len > 0 && msdp->count < net_device->max_pkt;
938 if (try_batch && msd_len + pktlen + net_device->pkt_align <
939 net_device->send_section_size) {
940 section_index = msdp->pkt->send_buf_index;
941
942 } else if (try_batch && msd_len + packet->rmsg_size <
943 net_device->send_section_size) {
944 section_index = msdp->pkt->send_buf_index;
945 packet->cp_partial = true;
946
947 } else if (pktlen + net_device->pkt_align <
948 net_device->send_section_size) {
949 section_index = netvsc_get_next_send_section(net_device);
950 if (unlikely(section_index == NETVSC_INVALID_INDEX)) {
951 ++ndev_ctx->eth_stats.tx_send_full;
952 } else {
953 move_pkt_msd(&msd_send, &msd_skb, msdp);
954 msd_len = 0;
955 }
956 }
957
958 /* Keep aggregating only if stack says more data is coming
959 * and not doing mixed modes send and not flow blocked
960 */
961 xmit_more = netdev_xmit_more() &&
962 !packet->cp_partial &&
963 !netif_xmit_stopped(netdev_get_tx_queue(ndev, packet->q_idx));
964
965 if (section_index != NETVSC_INVALID_INDEX) {
966 netvsc_copy_to_send_buf(net_device,
967 section_index, msd_len,
968 packet, rndis_msg, pb, xmit_more);
969
970 packet->send_buf_index = section_index;
971
972 if (packet->cp_partial) {
973 packet->page_buf_cnt -= packet->rmsg_pgcnt;
974 packet->total_data_buflen = msd_len + packet->rmsg_size;
975 } else {
976 packet->page_buf_cnt = 0;
977 packet->total_data_buflen += msd_len;
978 }
979
980 if (msdp->pkt) {
981 packet->total_packets += msdp->pkt->total_packets;
982 packet->total_bytes += msdp->pkt->total_bytes;
983 }
984
985 if (msdp->skb)
986 dev_consume_skb_any(msdp->skb);
987
988 if (xmit_more) {
989 msdp->skb = skb;
990 msdp->pkt = packet;
991 msdp->count++;
992 } else {
993 cur_send = packet;
994 msdp->skb = NULL;
995 msdp->pkt = NULL;
996 msdp->count = 0;
997 }
998 } else {
999 move_pkt_msd(&msd_send, &msd_skb, msdp);
1000 cur_send = packet;
1001 }
1002
1003 if (msd_send) {
1004 int m_ret = netvsc_send_pkt(device, msd_send, net_device,
1005 NULL, msd_skb);
1006
1007 if (m_ret != 0) {
1008 netvsc_free_send_slot(net_device,
1009 msd_send->send_buf_index);
1010 dev_kfree_skb_any(msd_skb);
1011 }
1012 }
1013
1014 if (cur_send)
1015 ret = netvsc_send_pkt(device, cur_send, net_device, pb, skb);
1016
1017 if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
1018 netvsc_free_send_slot(net_device, section_index);
1019
1020 return ret;
1021 }
1022
1023 /* Send pending recv completions */
1024 static int send_recv_completions(struct net_device *ndev,
1025 struct netvsc_device *nvdev,
1026 struct netvsc_channel *nvchan)
1027 {
1028 struct multi_recv_comp *mrc = &nvchan->mrc;
1029 struct recv_comp_msg {
1030 struct nvsp_message_header hdr;
1031 u32 status;
1032 } __packed;
1033 struct recv_comp_msg msg = {
1034 .hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE,
1035 };
1036 int ret;
1037
1038 while (mrc->first != mrc->next) {
1039 const struct recv_comp_data *rcd
1040 = mrc->slots + mrc->first;
1041
1042 msg.status = rcd->status;
1043 ret = vmbus_sendpacket(nvchan->channel, &msg, sizeof(msg),
1044 rcd->tid, VM_PKT_COMP, 0);
1045 if (unlikely(ret)) {
1046 struct net_device_context *ndev_ctx = netdev_priv(ndev);
1047
1048 ++ndev_ctx->eth_stats.rx_comp_busy;
1049 return ret;
1050 }
1051
1052 if (++mrc->first == nvdev->recv_completion_cnt)
1053 mrc->first = 0;
1054 }
1055
1056 /* receive completion ring has been emptied */
1057 if (unlikely(nvdev->destroy))
1058 wake_up(&nvdev->wait_drain);
1059
1060 return 0;
1061 }
1062
1063 /* Count how many receive completions are outstanding */
1064 static void recv_comp_slot_avail(const struct netvsc_device *nvdev,
1065 const struct multi_recv_comp *mrc,
1066 u32 *filled, u32 *avail)
1067 {
1068 u32 count = nvdev->recv_completion_cnt;
1069
1070 if (mrc->next >= mrc->first)
1071 *filled = mrc->next - mrc->first;
1072 else
1073 *filled = (count - mrc->first) + mrc->next;
1074
1075 *avail = count - *filled - 1;
1076 }
1077
1078 /* Add receive complete to ring to send to host. */
1079 static void enq_receive_complete(struct net_device *ndev,
1080 struct netvsc_device *nvdev, u16 q_idx,
1081 u64 tid, u32 status)
1082 {
1083 struct netvsc_channel *nvchan = &nvdev->chan_table[q_idx];
1084 struct multi_recv_comp *mrc = &nvchan->mrc;
1085 struct recv_comp_data *rcd;
1086 u32 filled, avail;
1087
1088 recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1089
1090 if (unlikely(filled > NAPI_POLL_WEIGHT)) {
1091 send_recv_completions(ndev, nvdev, nvchan);
1092 recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1093 }
1094
1095 if (unlikely(!avail)) {
1096 netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
1097 q_idx, tid);
1098 return;
1099 }
1100
1101 rcd = mrc->slots + mrc->next;
1102 rcd->tid = tid;
1103 rcd->status = status;
1104
1105 if (++mrc->next == nvdev->recv_completion_cnt)
1106 mrc->next = 0;
1107 }
1108
1109 static int netvsc_receive(struct net_device *ndev,
1110 struct netvsc_device *net_device,
1111 struct netvsc_channel *nvchan,
1112 const struct vmpacket_descriptor *desc,
1113 const struct nvsp_message *nvsp)
1114 {
1115 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1116 struct vmbus_channel *channel = nvchan->channel;
1117 const struct vmtransfer_page_packet_header *vmxferpage_packet
1118 = container_of(desc, const struct vmtransfer_page_packet_header, d);
1119 u16 q_idx = channel->offermsg.offer.sub_channel_index;
1120 char *recv_buf = net_device->recv_buf;
1121 u32 status = NVSP_STAT_SUCCESS;
1122 int i;
1123 int count = 0;
1124
1125 /* Make sure this is a valid nvsp packet */
1126 if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {
1127 netif_err(net_device_ctx, rx_err, ndev,
1128 "Unknown nvsp packet type received %u\n",
1129 nvsp->hdr.msg_type);
1130 return 0;
1131 }
1132
1133 if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
1134 netif_err(net_device_ctx, rx_err, ndev,
1135 "Invalid xfer page set id - expecting %x got %x\n",
1136 NETVSC_RECEIVE_BUFFER_ID,
1137 vmxferpage_packet->xfer_pageset_id);
1138 return 0;
1139 }
1140
1141 count = vmxferpage_packet->range_cnt;
1142
1143 /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1144 for (i = 0; i < count; i++) {
1145 u32 offset = vmxferpage_packet->ranges[i].byte_offset;
1146 u32 buflen = vmxferpage_packet->ranges[i].byte_count;
1147 void *data;
1148 int ret;
1149
1150 if (unlikely(offset + buflen > net_device->recv_buf_size)) {
1151 nvchan->rsc.cnt = 0;
1152 status = NVSP_STAT_FAIL;
1153 netif_err(net_device_ctx, rx_err, ndev,
1154 "Packet offset:%u + len:%u too big\n",
1155 offset, buflen);
1156
1157 continue;
1158 }
1159
1160 data = recv_buf + offset;
1161
1162 nvchan->rsc.is_last = (i == count - 1);
1163
1164 trace_rndis_recv(ndev, q_idx, data);
1165
1166 /* Pass it to the upper layer */
1167 ret = rndis_filter_receive(ndev, net_device,
1168 nvchan, data, buflen);
1169
1170 if (unlikely(ret != NVSP_STAT_SUCCESS))
1171 status = NVSP_STAT_FAIL;
1172 }
1173
1174 enq_receive_complete(ndev, net_device, q_idx,
1175 vmxferpage_packet->d.trans_id, status);
1176
1177 return count;
1178 }
1179
1180 static void netvsc_send_table(struct net_device *ndev,
1181 const struct nvsp_message *nvmsg)
1182 {
1183 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1184 u32 count, *tab;
1185 int i;
1186
1187 count = nvmsg->msg.v5_msg.send_table.count;
1188 if (count != VRSS_SEND_TAB_SIZE) {
1189 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1190 return;
1191 }
1192
1193 tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1194 nvmsg->msg.v5_msg.send_table.offset);
1195
1196 for (i = 0; i < count; i++)
1197 net_device_ctx->tx_table[i] = tab[i];
1198 }
1199
1200 static void netvsc_send_vf(struct net_device *ndev,
1201 const struct nvsp_message *nvmsg)
1202 {
1203 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1204
1205 net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1206 net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1207 netdev_info(ndev, "VF slot %u %s\n",
1208 net_device_ctx->vf_serial,
1209 net_device_ctx->vf_alloc ? "added" : "removed");
1210 }
1211
1212 static void netvsc_receive_inband(struct net_device *ndev,
1213 const struct nvsp_message *nvmsg)
1214 {
1215 switch (nvmsg->hdr.msg_type) {
1216 case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1217 netvsc_send_table(ndev, nvmsg);
1218 break;
1219
1220 case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1221 netvsc_send_vf(ndev, nvmsg);
1222 break;
1223 }
1224 }
1225
1226 static int netvsc_process_raw_pkt(struct hv_device *device,
1227 struct netvsc_channel *nvchan,
1228 struct netvsc_device *net_device,
1229 struct net_device *ndev,
1230 const struct vmpacket_descriptor *desc,
1231 int budget)
1232 {
1233 struct vmbus_channel *channel = nvchan->channel;
1234 const struct nvsp_message *nvmsg = hv_pkt_data(desc);
1235
1236 trace_nvsp_recv(ndev, channel, nvmsg);
1237
1238 switch (desc->type) {
1239 case VM_PKT_COMP:
1240 netvsc_send_completion(ndev, net_device, channel,
1241 desc, budget);
1242 break;
1243
1244 case VM_PKT_DATA_USING_XFER_PAGES:
1245 return netvsc_receive(ndev, net_device, nvchan,
1246 desc, nvmsg);
1247 break;
1248
1249 case VM_PKT_DATA_INBAND:
1250 netvsc_receive_inband(ndev, nvmsg);
1251 break;
1252
1253 default:
1254 netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1255 desc->type, desc->trans_id);
1256 break;
1257 }
1258
1259 return 0;
1260 }
1261
1262 static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
1263 {
1264 struct vmbus_channel *primary = channel->primary_channel;
1265
1266 return primary ? primary->device_obj : channel->device_obj;
1267 }
1268
1269 /* Network processing softirq
1270 * Process data in incoming ring buffer from host
1271 * Stops when ring is empty or budget is met or exceeded.
1272 */
1273 int netvsc_poll(struct napi_struct *napi, int budget)
1274 {
1275 struct netvsc_channel *nvchan
1276 = container_of(napi, struct netvsc_channel, napi);
1277 struct netvsc_device *net_device = nvchan->net_device;
1278 struct vmbus_channel *channel = nvchan->channel;
1279 struct hv_device *device = netvsc_channel_to_device(channel);
1280 struct net_device *ndev = hv_get_drvdata(device);
1281 int work_done = 0;
1282 int ret;
1283
1284 /* If starting a new interval */
1285 if (!nvchan->desc)
1286 nvchan->desc = hv_pkt_iter_first(channel);
1287
1288 while (nvchan->desc && work_done < budget) {
1289 work_done += netvsc_process_raw_pkt(device, nvchan, net_device,
1290 ndev, nvchan->desc, budget);
1291 nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
1292 }
1293
1294 /* Send any pending receive completions */
1295 ret = send_recv_completions(ndev, net_device, nvchan);
1296
1297 /* If it did not exhaust NAPI budget this time
1298 * and not doing busy poll
1299 * then re-enable host interrupts
1300 * and reschedule if ring is not empty
1301 * or sending receive completion failed.
1302 */
1303 if (work_done < budget &&
1304 napi_complete_done(napi, work_done) &&
1305 (ret || hv_end_read(&channel->inbound)) &&
1306 napi_schedule_prep(napi)) {
1307 hv_begin_read(&channel->inbound);
1308 __napi_schedule(napi);
1309 }
1310
1311 /* Driver may overshoot since multiple packets per descriptor */
1312 return min(work_done, budget);
1313 }
1314
1315 /* Call back when data is available in host ring buffer.
1316 * Processing is deferred until network softirq (NAPI)
1317 */
1318 void netvsc_channel_cb(void *context)
1319 {
1320 struct netvsc_channel *nvchan = context;
1321 struct vmbus_channel *channel = nvchan->channel;
1322 struct hv_ring_buffer_info *rbi = &channel->inbound;
1323
1324 /* preload first vmpacket descriptor */
1325 prefetch(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
1326
1327 if (napi_schedule_prep(&nvchan->napi)) {
1328 /* disable interrupts from host */
1329 hv_begin_read(rbi);
1330
1331 __napi_schedule_irqoff(&nvchan->napi);
1332 }
1333 }
1334
1335 /*
1336 * netvsc_device_add - Callback when the device belonging to this
1337 * driver is added
1338 */
1339 struct netvsc_device *netvsc_device_add(struct hv_device *device,
1340 const struct netvsc_device_info *device_info)
1341 {
1342 int i, ret = 0;
1343 struct netvsc_device *net_device;
1344 struct net_device *ndev = hv_get_drvdata(device);
1345 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1346
1347 net_device = alloc_net_device();
1348 if (!net_device)
1349 return ERR_PTR(-ENOMEM);
1350
1351 for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
1352 net_device_ctx->tx_table[i] = 0;
1353
1354 /* Because the device uses NAPI, all the interrupt batching and
1355 * control is done via Net softirq, not the channel handling
1356 */
1357 set_channel_read_mode(device->channel, HV_CALL_ISR);
1358
1359 /* If we're reopening the device we may have multiple queues, fill the
1360 * chn_table with the default channel to use it before subchannels are
1361 * opened.
1362 * Initialize the channel state before we open;
1363 * we can be interrupted as soon as we open the channel.
1364 */
1365
1366 for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
1367 struct netvsc_channel *nvchan = &net_device->chan_table[i];
1368
1369 nvchan->channel = device->channel;
1370 nvchan->net_device = net_device;
1371 u64_stats_init(&nvchan->tx_stats.syncp);
1372 u64_stats_init(&nvchan->rx_stats.syncp);
1373 }
1374
1375 /* Enable NAPI handler before init callbacks */
1376 netif_napi_add(ndev, &net_device->chan_table[0].napi,
1377 netvsc_poll, NAPI_POLL_WEIGHT);
1378
1379 /* Open the channel */
1380 ret = vmbus_open(device->channel, netvsc_ring_bytes,
1381 netvsc_ring_bytes, NULL, 0,
1382 netvsc_channel_cb, net_device->chan_table);
1383
1384 if (ret != 0) {
1385 netdev_err(ndev, "unable to open channel: %d\n", ret);
1386 goto cleanup;
1387 }
1388
1389 /* Channel is opened */
1390 netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
1391
1392 napi_enable(&net_device->chan_table[0].napi);
1393
1394 /* Connect with the NetVsp */
1395 ret = netvsc_connect_vsp(device, net_device, device_info);
1396 if (ret != 0) {
1397 netdev_err(ndev,
1398 "unable to connect to NetVSP - %d\n", ret);
1399 goto close;
1400 }
1401
1402 /* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1403 * populated.
1404 */
1405 rcu_assign_pointer(net_device_ctx->nvdev, net_device);
1406
1407 return net_device;
1408
1409 close:
1410 RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
1411 napi_disable(&net_device->chan_table[0].napi);
1412
1413 /* Now, we can close the channel safely */
1414 vmbus_close(device->channel);
1415
1416 cleanup:
1417 netif_napi_del(&net_device->chan_table[0].napi);
1418 free_netvsc_device(&net_device->rcu);
1419
1420 return ERR_PTR(ret);
1421 }
Linux with added FPC-III support