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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / net / hyperv / netvsc.c
blobae3f3084c2ed29bd19522f27f51283275310beaa
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 xdp_rxq_info_unreg(&nvdev->chan_table[i].xdp_rxq);
127 vfree(nvdev->chan_table[i].mrc.slots);
128 }
129
130 kfree(nvdev);
131 }
132
133 static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
134 {
135 call_rcu(&nvdev->rcu, free_netvsc_device);
136 }
137
138 static void netvsc_revoke_recv_buf(struct hv_device *device,
139 struct netvsc_device *net_device,
140 struct net_device *ndev)
141 {
142 struct nvsp_message *revoke_packet;
143 int ret;
144
145 /*
146 * If we got a section count, it means we received a
147 * SendReceiveBufferComplete msg (ie sent
148 * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
149 * to send a revoke msg here
150 */
151 if (net_device->recv_section_cnt) {
152 /* Send the revoke receive buffer */
153 revoke_packet = &net_device->revoke_packet;
154 memset(revoke_packet, 0, sizeof(struct nvsp_message));
155
156 revoke_packet->hdr.msg_type =
157 NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
158 revoke_packet->msg.v1_msg.
159 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
160
161 trace_nvsp_send(ndev, revoke_packet);
162
163 ret = vmbus_sendpacket(device->channel,
164 revoke_packet,
165 sizeof(struct nvsp_message),
166 (unsigned long)revoke_packet,
167 VM_PKT_DATA_INBAND, 0);
168 /* If the failure is because the channel is rescinded;
169 * ignore the failure since we cannot send on a rescinded
170 * channel. This would allow us to properly cleanup
171 * even when the channel is rescinded.
172 */
173 if (device->channel->rescind)
174 ret = 0;
175 /*
176 * If we failed here, we might as well return and
177 * have a leak rather than continue and a bugchk
178 */
179 if (ret != 0) {
180 netdev_err(ndev, "unable to send "
181 "revoke receive buffer to netvsp\n");
182 return;
183 }
184 net_device->recv_section_cnt = 0;
185 }
186 }
187
188 static void netvsc_revoke_send_buf(struct hv_device *device,
189 struct netvsc_device *net_device,
190 struct net_device *ndev)
191 {
192 struct nvsp_message *revoke_packet;
193 int ret;
194
195 /* Deal with the send buffer we may have setup.
196 * If we got a send section size, it means we received a
197 * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
198 * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
199 * to send a revoke msg here
200 */
201 if (net_device->send_section_cnt) {
202 /* Send the revoke receive buffer */
203 revoke_packet = &net_device->revoke_packet;
204 memset(revoke_packet, 0, sizeof(struct nvsp_message));
205
206 revoke_packet->hdr.msg_type =
207 NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
208 revoke_packet->msg.v1_msg.revoke_send_buf.id =
209 NETVSC_SEND_BUFFER_ID;
210
211 trace_nvsp_send(ndev, revoke_packet);
212
213 ret = vmbus_sendpacket(device->channel,
214 revoke_packet,
215 sizeof(struct nvsp_message),
216 (unsigned long)revoke_packet,
217 VM_PKT_DATA_INBAND, 0);
218
219 /* If the failure is because the channel is rescinded;
220 * ignore the failure since we cannot send on a rescinded
221 * channel. This would allow us to properly cleanup
222 * even when the channel is rescinded.
223 */
224 if (device->channel->rescind)
225 ret = 0;
226
227 /* If we failed here, we might as well return and
228 * have a leak rather than continue and a bugchk
229 */
230 if (ret != 0) {
231 netdev_err(ndev, "unable to send "
232 "revoke send buffer to netvsp\n");
233 return;
234 }
235 net_device->send_section_cnt = 0;
236 }
237 }
238
239 static void netvsc_teardown_recv_gpadl(struct hv_device *device,
240 struct netvsc_device *net_device,
241 struct net_device *ndev)
242 {
243 int ret;
244
245 if (net_device->recv_buf_gpadl_handle) {
246 ret = vmbus_teardown_gpadl(device->channel,
247 net_device->recv_buf_gpadl_handle);
248
249 /* If we failed here, we might as well return and have a leak
250 * rather than continue and a bugchk
251 */
252 if (ret != 0) {
253 netdev_err(ndev,
254 "unable to teardown receive buffer's gpadl\n");
255 return;
256 }
257 net_device->recv_buf_gpadl_handle = 0;
258 }
259 }
260
261 static void netvsc_teardown_send_gpadl(struct hv_device *device,
262 struct netvsc_device *net_device,
263 struct net_device *ndev)
264 {
265 int ret;
266
267 if (net_device->send_buf_gpadl_handle) {
268 ret = vmbus_teardown_gpadl(device->channel,
269 net_device->send_buf_gpadl_handle);
270
271 /* If we failed here, we might as well return and have a leak
272 * rather than continue and a bugchk
273 */
274 if (ret != 0) {
275 netdev_err(ndev,
276 "unable to teardown send buffer's gpadl\n");
277 return;
278 }
279 net_device->send_buf_gpadl_handle = 0;
280 }
281 }
282
283 int netvsc_alloc_recv_comp_ring(struct netvsc_device *net_device, u32 q_idx)
284 {
285 struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
286 int node = cpu_to_node(nvchan->channel->target_cpu);
287 size_t size;
288
289 size = net_device->recv_completion_cnt * sizeof(struct recv_comp_data);
290 nvchan->mrc.slots = vzalloc_node(size, node);
291 if (!nvchan->mrc.slots)
292 nvchan->mrc.slots = vzalloc(size);
293
294 return nvchan->mrc.slots ? 0 : -ENOMEM;
295 }
296
297 static int netvsc_init_buf(struct hv_device *device,
298 struct netvsc_device *net_device,
299 const struct netvsc_device_info *device_info)
300 {
301 struct nvsp_1_message_send_receive_buffer_complete *resp;
302 struct net_device *ndev = hv_get_drvdata(device);
303 struct nvsp_message *init_packet;
304 unsigned int buf_size;
305 size_t map_words;
306 int ret = 0;
307
308 /* Get receive buffer area. */
309 buf_size = device_info->recv_sections * device_info->recv_section_size;
310 buf_size = roundup(buf_size, PAGE_SIZE);
311
312 /* Legacy hosts only allow smaller receive buffer */
313 if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
314 buf_size = min_t(unsigned int, buf_size,
315 NETVSC_RECEIVE_BUFFER_SIZE_LEGACY);
316
317 net_device->recv_buf = vzalloc(buf_size);
318 if (!net_device->recv_buf) {
319 netdev_err(ndev,
320 "unable to allocate receive buffer of size %u\n",
321 buf_size);
322 ret = -ENOMEM;
323 goto cleanup;
324 }
325
326 net_device->recv_buf_size = buf_size;
327
328 /*
329 * Establish the gpadl handle for this buffer on this
330 * channel. Note: This call uses the vmbus connection rather
331 * than the channel to establish the gpadl handle.
332 */
333 ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
334 buf_size,
335 &net_device->recv_buf_gpadl_handle);
336 if (ret != 0) {
337 netdev_err(ndev,
338 "unable to establish receive buffer's gpadl\n");
339 goto cleanup;
340 }
341
342 /* Notify the NetVsp of the gpadl handle */
343 init_packet = &net_device->channel_init_pkt;
344 memset(init_packet, 0, sizeof(struct nvsp_message));
345 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
346 init_packet->msg.v1_msg.send_recv_buf.
347 gpadl_handle = net_device->recv_buf_gpadl_handle;
348 init_packet->msg.v1_msg.
349 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
350
351 trace_nvsp_send(ndev, init_packet);
352
353 /* Send the gpadl notification request */
354 ret = vmbus_sendpacket(device->channel, init_packet,
355 sizeof(struct nvsp_message),
356 (unsigned long)init_packet,
357 VM_PKT_DATA_INBAND,
358 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
359 if (ret != 0) {
360 netdev_err(ndev,
361 "unable to send receive buffer's gpadl to netvsp\n");
362 goto cleanup;
363 }
364
365 wait_for_completion(&net_device->channel_init_wait);
366
367 /* Check the response */
368 resp = &init_packet->msg.v1_msg.send_recv_buf_complete;
369 if (resp->status != NVSP_STAT_SUCCESS) {
370 netdev_err(ndev,
371 "Unable to complete receive buffer initialization with NetVsp - status %d\n",
372 resp->status);
373 ret = -EINVAL;
374 goto cleanup;
375 }
376
377 /* Parse the response */
378 netdev_dbg(ndev, "Receive sections: %u sub_allocs: size %u count: %u\n",
379 resp->num_sections, resp->sections[0].sub_alloc_size,
380 resp->sections[0].num_sub_allocs);
381
382 /* There should only be one section for the entire receive buffer */
383 if (resp->num_sections != 1 || resp->sections[0].offset != 0) {
384 ret = -EINVAL;
385 goto cleanup;
386 }
387
388 net_device->recv_section_size = resp->sections[0].sub_alloc_size;
389 net_device->recv_section_cnt = resp->sections[0].num_sub_allocs;
390
391 /* Setup receive completion ring */
392 net_device->recv_completion_cnt
393 = round_up(net_device->recv_section_cnt + 1,
394 PAGE_SIZE / sizeof(u64));
395 ret = netvsc_alloc_recv_comp_ring(net_device, 0);
396 if (ret)
397 goto cleanup;
398
399 /* Now setup the send buffer. */
400 buf_size = device_info->send_sections * device_info->send_section_size;
401 buf_size = round_up(buf_size, PAGE_SIZE);
402
403 net_device->send_buf = vzalloc(buf_size);
404 if (!net_device->send_buf) {
405 netdev_err(ndev, "unable to allocate send buffer of size %u\n",
406 buf_size);
407 ret = -ENOMEM;
408 goto cleanup;
409 }
410
411 /* Establish the gpadl handle for this buffer on this
412 * channel. Note: This call uses the vmbus connection rather
413 * than the channel to establish the gpadl handle.
414 */
415 ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
416 buf_size,
417 &net_device->send_buf_gpadl_handle);
418 if (ret != 0) {
419 netdev_err(ndev,
420 "unable to establish send buffer's gpadl\n");
421 goto cleanup;
422 }
423
424 /* Notify the NetVsp of the gpadl handle */
425 init_packet = &net_device->channel_init_pkt;
426 memset(init_packet, 0, sizeof(struct nvsp_message));
427 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
428 init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
429 net_device->send_buf_gpadl_handle;
430 init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
431
432 trace_nvsp_send(ndev, init_packet);
433
434 /* Send the gpadl notification request */
435 ret = vmbus_sendpacket(device->channel, init_packet,
436 sizeof(struct nvsp_message),
437 (unsigned long)init_packet,
438 VM_PKT_DATA_INBAND,
439 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
440 if (ret != 0) {
441 netdev_err(ndev,
442 "unable to send send buffer's gpadl to netvsp\n");
443 goto cleanup;
444 }
445
446 wait_for_completion(&net_device->channel_init_wait);
447
448 /* Check the response */
449 if (init_packet->msg.v1_msg.
450 send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
451 netdev_err(ndev, "Unable to complete send buffer "
452 "initialization with NetVsp - status %d\n",
453 init_packet->msg.v1_msg.
454 send_send_buf_complete.status);
455 ret = -EINVAL;
456 goto cleanup;
457 }
458
459 /* Parse the response */
460 net_device->send_section_size = init_packet->msg.
461 v1_msg.send_send_buf_complete.section_size;
462
463 /* Section count is simply the size divided by the section size. */
464 net_device->send_section_cnt = buf_size / net_device->send_section_size;
465
466 netdev_dbg(ndev, "Send section size: %d, Section count:%d\n",
467 net_device->send_section_size, net_device->send_section_cnt);
468
469 /* Setup state for managing the send buffer. */
470 map_words = DIV_ROUND_UP(net_device->send_section_cnt, BITS_PER_LONG);
471
472 net_device->send_section_map = kcalloc(map_words, sizeof(ulong), GFP_KERNEL);
473 if (net_device->send_section_map == NULL) {
474 ret = -ENOMEM;
475 goto cleanup;
476 }
477
478 goto exit;
479
480 cleanup:
481 netvsc_revoke_recv_buf(device, net_device, ndev);
482 netvsc_revoke_send_buf(device, net_device, ndev);
483 netvsc_teardown_recv_gpadl(device, net_device, ndev);
484 netvsc_teardown_send_gpadl(device, net_device, ndev);
485
486 exit:
487 return ret;
488 }
489
490 /* Negotiate NVSP protocol version */
491 static int negotiate_nvsp_ver(struct hv_device *device,
492 struct netvsc_device *net_device,
493 struct nvsp_message *init_packet,
494 u32 nvsp_ver)
495 {
496 struct net_device *ndev = hv_get_drvdata(device);
497 int ret;
498
499 memset(init_packet, 0, sizeof(struct nvsp_message));
500 init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
501 init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
502 init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
503 trace_nvsp_send(ndev, init_packet);
504
505 /* Send the init request */
506 ret = vmbus_sendpacket(device->channel, init_packet,
507 sizeof(struct nvsp_message),
508 (unsigned long)init_packet,
509 VM_PKT_DATA_INBAND,
510 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
511
512 if (ret != 0)
513 return ret;
514
515 wait_for_completion(&net_device->channel_init_wait);
516
517 if (init_packet->msg.init_msg.init_complete.status !=
518 NVSP_STAT_SUCCESS)
519 return -EINVAL;
520
521 if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
522 return 0;
523
524 /* NVSPv2 or later: Send NDIS config */
525 memset(init_packet, 0, sizeof(struct nvsp_message));
526 init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
527 init_packet->msg.v2_msg.send_ndis_config.mtu = ndev->mtu + ETH_HLEN;
528 init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
529
530 if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
531 init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
532
533 /* Teaming bit is needed to receive link speed updates */
534 init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
535 }
536
537 if (nvsp_ver >= NVSP_PROTOCOL_VERSION_61)
538 init_packet->msg.v2_msg.send_ndis_config.capability.rsc = 1;
539
540 trace_nvsp_send(ndev, init_packet);
541
542 ret = vmbus_sendpacket(device->channel, init_packet,
543 sizeof(struct nvsp_message),
544 (unsigned long)init_packet,
545 VM_PKT_DATA_INBAND, 0);
546
547 return ret;
548 }
549
550 static int netvsc_connect_vsp(struct hv_device *device,
551 struct netvsc_device *net_device,
552 const struct netvsc_device_info *device_info)
553 {
554 struct net_device *ndev = hv_get_drvdata(device);
555 static const u32 ver_list[] = {
556 NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
557 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5,
558 NVSP_PROTOCOL_VERSION_6, NVSP_PROTOCOL_VERSION_61
559 };
560 struct nvsp_message *init_packet;
561 int ndis_version, i, ret;
562
563 init_packet = &net_device->channel_init_pkt;
564
565 /* Negotiate the latest NVSP protocol supported */
566 for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
567 if (negotiate_nvsp_ver(device, net_device, init_packet,
568 ver_list[i]) == 0) {
569 net_device->nvsp_version = ver_list[i];
570 break;
571 }
572
573 if (i < 0) {
574 ret = -EPROTO;
575 goto cleanup;
576 }
577
578 pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
579
580 /* Send the ndis version */
581 memset(init_packet, 0, sizeof(struct nvsp_message));
582
583 if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
584 ndis_version = 0x00060001;
585 else
586 ndis_version = 0x0006001e;
587
588 init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
589 init_packet->msg.v1_msg.
590 send_ndis_ver.ndis_major_ver =
591 (ndis_version & 0xFFFF0000) >> 16;
592 init_packet->msg.v1_msg.
593 send_ndis_ver.ndis_minor_ver =
594 ndis_version & 0xFFFF;
595
596 trace_nvsp_send(ndev, init_packet);
597
598 /* Send the init request */
599 ret = vmbus_sendpacket(device->channel, init_packet,
600 sizeof(struct nvsp_message),
601 (unsigned long)init_packet,
602 VM_PKT_DATA_INBAND, 0);
603 if (ret != 0)
604 goto cleanup;
605
606
607 ret = netvsc_init_buf(device, net_device, device_info);
608
609 cleanup:
610 return ret;
611 }
612
613 /*
614 * netvsc_device_remove - Callback when the root bus device is removed
615 */
616 void netvsc_device_remove(struct hv_device *device)
617 {
618 struct net_device *ndev = hv_get_drvdata(device);
619 struct net_device_context *net_device_ctx = netdev_priv(ndev);
620 struct netvsc_device *net_device
621 = rtnl_dereference(net_device_ctx->nvdev);
622 int i;
623
624 /*
625 * Revoke receive buffer. If host is pre-Win2016 then tear down
626 * receive buffer GPADL. Do the same for send buffer.
627 */
628 netvsc_revoke_recv_buf(device, net_device, ndev);
629 if (vmbus_proto_version < VERSION_WIN10)
630 netvsc_teardown_recv_gpadl(device, net_device, ndev);
631
632 netvsc_revoke_send_buf(device, net_device, ndev);
633 if (vmbus_proto_version < VERSION_WIN10)
634 netvsc_teardown_send_gpadl(device, net_device, ndev);
635
636 RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
637
638 /* And disassociate NAPI context from device */
639 for (i = 0; i < net_device->num_chn; i++)
640 netif_napi_del(&net_device->chan_table[i].napi);
641
642 /*
643 * At this point, no one should be accessing net_device
644 * except in here
645 */
646 netdev_dbg(ndev, "net device safe to remove\n");
647
648 /* Now, we can close the channel safely */
649 vmbus_close(device->channel);
650
651 /*
652 * If host is Win2016 or higher then we do the GPADL tear down
653 * here after VMBus is closed.
654 */
655 if (vmbus_proto_version >= VERSION_WIN10) {
656 netvsc_teardown_recv_gpadl(device, net_device, ndev);
657 netvsc_teardown_send_gpadl(device, net_device, ndev);
658 }
659
660 /* Release all resources */
661 free_netvsc_device_rcu(net_device);
662 }
663
664 #define RING_AVAIL_PERCENT_HIWATER 20
665 #define RING_AVAIL_PERCENT_LOWATER 10
666
667 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
668 u32 index)
669 {
670 sync_change_bit(index, net_device->send_section_map);
671 }
672
673 static void netvsc_send_tx_complete(struct net_device *ndev,
674 struct netvsc_device *net_device,
675 struct vmbus_channel *channel,
676 const struct vmpacket_descriptor *desc,
677 int budget)
678 {
679 struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
680 struct net_device_context *ndev_ctx = netdev_priv(ndev);
681 u16 q_idx = 0;
682 int queue_sends;
683
684 /* Notify the layer above us */
685 if (likely(skb)) {
686 const struct hv_netvsc_packet *packet
687 = (struct hv_netvsc_packet *)skb->cb;
688 u32 send_index = packet->send_buf_index;
689 struct netvsc_stats *tx_stats;
690
691 if (send_index != NETVSC_INVALID_INDEX)
692 netvsc_free_send_slot(net_device, send_index);
693 q_idx = packet->q_idx;
694
695 tx_stats = &net_device->chan_table[q_idx].tx_stats;
696
697 u64_stats_update_begin(&tx_stats->syncp);
698 tx_stats->packets += packet->total_packets;
699 tx_stats->bytes += packet->total_bytes;
700 u64_stats_update_end(&tx_stats->syncp);
701
702 napi_consume_skb(skb, budget);
703 }
704
705 queue_sends =
706 atomic_dec_return(&net_device->chan_table[q_idx].queue_sends);
707
708 if (unlikely(net_device->destroy)) {
709 if (queue_sends == 0)
710 wake_up(&net_device->wait_drain);
711 } else {
712 struct netdev_queue *txq = netdev_get_tx_queue(ndev, q_idx);
713
714 if (netif_tx_queue_stopped(txq) && !net_device->tx_disable &&
715 (hv_get_avail_to_write_percent(&channel->outbound) >
716 RING_AVAIL_PERCENT_HIWATER || queue_sends < 1)) {
717 netif_tx_wake_queue(txq);
718 ndev_ctx->eth_stats.wake_queue++;
719 }
720 }
721 }
722
723 static void netvsc_send_completion(struct net_device *ndev,
724 struct netvsc_device *net_device,
725 struct vmbus_channel *incoming_channel,
726 const struct vmpacket_descriptor *desc,
727 int budget)
728 {
729 const struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
730
731 switch (nvsp_packet->hdr.msg_type) {
732 case NVSP_MSG_TYPE_INIT_COMPLETE:
733 case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
734 case NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE:
735 case NVSP_MSG5_TYPE_SUBCHANNEL:
736 /* Copy the response back */
737 memcpy(&net_device->channel_init_pkt, nvsp_packet,
738 sizeof(struct nvsp_message));
739 complete(&net_device->channel_init_wait);
740 break;
741
742 case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
743 netvsc_send_tx_complete(ndev, net_device, incoming_channel,
744 desc, budget);
745 break;
746
747 default:
748 netdev_err(ndev,
749 "Unknown send completion type %d received!!\n",
750 nvsp_packet->hdr.msg_type);
751 }
752 }
753
754 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
755 {
756 unsigned long *map_addr = net_device->send_section_map;
757 unsigned int i;
758
759 for_each_clear_bit(i, map_addr, net_device->send_section_cnt) {
760 if (sync_test_and_set_bit(i, map_addr) == 0)
761 return i;
762 }
763
764 return NETVSC_INVALID_INDEX;
765 }
766
767 static void netvsc_copy_to_send_buf(struct netvsc_device *net_device,
768 unsigned int section_index,
769 u32 pend_size,
770 struct hv_netvsc_packet *packet,
771 struct rndis_message *rndis_msg,
772 struct hv_page_buffer *pb,
773 bool xmit_more)
774 {
775 char *start = net_device->send_buf;
776 char *dest = start + (section_index * net_device->send_section_size)
777 + pend_size;
778 int i;
779 u32 padding = 0;
780 u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
781 packet->page_buf_cnt;
782 u32 remain;
783
784 /* Add padding */
785 remain = packet->total_data_buflen & (net_device->pkt_align - 1);
786 if (xmit_more && remain) {
787 padding = net_device->pkt_align - remain;
788 rndis_msg->msg_len += padding;
789 packet->total_data_buflen += padding;
790 }
791
792 for (i = 0; i < page_count; i++) {
793 char *src = phys_to_virt(pb[i].pfn << PAGE_SHIFT);
794 u32 offset = pb[i].offset;
795 u32 len = pb[i].len;
796
797 memcpy(dest, (src + offset), len);
798 dest += len;
799 }
800
801 if (padding)
802 memset(dest, 0, padding);
803 }
804
805 static inline int netvsc_send_pkt(
806 struct hv_device *device,
807 struct hv_netvsc_packet *packet,
808 struct netvsc_device *net_device,
809 struct hv_page_buffer *pb,
810 struct sk_buff *skb)
811 {
812 struct nvsp_message nvmsg;
813 struct nvsp_1_message_send_rndis_packet *rpkt =
814 &nvmsg.msg.v1_msg.send_rndis_pkt;
815 struct netvsc_channel * const nvchan =
816 &net_device->chan_table[packet->q_idx];
817 struct vmbus_channel *out_channel = nvchan->channel;
818 struct net_device *ndev = hv_get_drvdata(device);
819 struct net_device_context *ndev_ctx = netdev_priv(ndev);
820 struct netdev_queue *txq = netdev_get_tx_queue(ndev, packet->q_idx);
821 u64 req_id;
822 int ret;
823 u32 ring_avail = hv_get_avail_to_write_percent(&out_channel->outbound);
824
825 nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
826 if (skb)
827 rpkt->channel_type = 0; /* 0 is RMC_DATA */
828 else
829 rpkt->channel_type = 1; /* 1 is RMC_CONTROL */
830
831 rpkt->send_buf_section_index = packet->send_buf_index;
832 if (packet->send_buf_index == NETVSC_INVALID_INDEX)
833 rpkt->send_buf_section_size = 0;
834 else
835 rpkt->send_buf_section_size = packet->total_data_buflen;
836
837 req_id = (ulong)skb;
838
839 if (out_channel->rescind)
840 return -ENODEV;
841
842 trace_nvsp_send_pkt(ndev, out_channel, rpkt);
843
844 if (packet->page_buf_cnt) {
845 if (packet->cp_partial)
846 pb += packet->rmsg_pgcnt;
847
848 ret = vmbus_sendpacket_pagebuffer(out_channel,
849 pb, packet->page_buf_cnt,
850 &nvmsg, sizeof(nvmsg),
851 req_id);
852 } else {
853 ret = vmbus_sendpacket(out_channel,
854 &nvmsg, sizeof(nvmsg),
855 req_id, VM_PKT_DATA_INBAND,
856 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
857 }
858
859 if (ret == 0) {
860 atomic_inc_return(&nvchan->queue_sends);
861
862 if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
863 netif_tx_stop_queue(txq);
864 ndev_ctx->eth_stats.stop_queue++;
865 }
866 } else if (ret == -EAGAIN) {
867 netif_tx_stop_queue(txq);
868 ndev_ctx->eth_stats.stop_queue++;
869 } else {
870 netdev_err(ndev,
871 "Unable to send packet pages %u len %u, ret %d\n",
872 packet->page_buf_cnt, packet->total_data_buflen,
873 ret);
874 }
875
876 if (netif_tx_queue_stopped(txq) &&
877 atomic_read(&nvchan->queue_sends) < 1 &&
878 !net_device->tx_disable) {
879 netif_tx_wake_queue(txq);
880 ndev_ctx->eth_stats.wake_queue++;
881 if (ret == -EAGAIN)
882 ret = -ENOSPC;
883 }
884
885 return ret;
886 }
887
888 /* Move packet out of multi send data (msd), and clear msd */
889 static inline void move_pkt_msd(struct hv_netvsc_packet **msd_send,
890 struct sk_buff **msd_skb,
891 struct multi_send_data *msdp)
892 {
893 *msd_skb = msdp->skb;
894 *msd_send = msdp->pkt;
895 msdp->skb = NULL;
896 msdp->pkt = NULL;
897 msdp->count = 0;
898 }
899
900 /* RCU already held by caller */
901 int netvsc_send(struct net_device *ndev,
902 struct hv_netvsc_packet *packet,
903 struct rndis_message *rndis_msg,
904 struct hv_page_buffer *pb,
905 struct sk_buff *skb,
906 bool xdp_tx)
907 {
908 struct net_device_context *ndev_ctx = netdev_priv(ndev);
909 struct netvsc_device *net_device
910 = rcu_dereference_bh(ndev_ctx->nvdev);
911 struct hv_device *device = ndev_ctx->device_ctx;
912 int ret = 0;
913 struct netvsc_channel *nvchan;
914 u32 pktlen = packet->total_data_buflen, msd_len = 0;
915 unsigned int section_index = NETVSC_INVALID_INDEX;
916 struct multi_send_data *msdp;
917 struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
918 struct sk_buff *msd_skb = NULL;
919 bool try_batch, xmit_more;
920
921 /* If device is rescinded, return error and packet will get dropped. */
922 if (unlikely(!net_device || net_device->destroy))
923 return -ENODEV;
924
925 nvchan = &net_device->chan_table[packet->q_idx];
926 packet->send_buf_index = NETVSC_INVALID_INDEX;
927 packet->cp_partial = false;
928
929 /* Send a control message or XDP packet directly without accessing
930 * msd (Multi-Send Data) field which may be changed during data packet
931 * processing.
932 */
933 if (!skb || xdp_tx)
934 return netvsc_send_pkt(device, packet, net_device, pb, skb);
935
936 /* batch packets in send buffer if possible */
937 msdp = &nvchan->msd;
938 if (msdp->pkt)
939 msd_len = msdp->pkt->total_data_buflen;
940
941 try_batch = msd_len > 0 && msdp->count < net_device->max_pkt;
942 if (try_batch && msd_len + pktlen + net_device->pkt_align <
943 net_device->send_section_size) {
944 section_index = msdp->pkt->send_buf_index;
945
946 } else if (try_batch && msd_len + packet->rmsg_size <
947 net_device->send_section_size) {
948 section_index = msdp->pkt->send_buf_index;
949 packet->cp_partial = true;
950
951 } else if (pktlen + net_device->pkt_align <
952 net_device->send_section_size) {
953 section_index = netvsc_get_next_send_section(net_device);
954 if (unlikely(section_index == NETVSC_INVALID_INDEX)) {
955 ++ndev_ctx->eth_stats.tx_send_full;
956 } else {
957 move_pkt_msd(&msd_send, &msd_skb, msdp);
958 msd_len = 0;
959 }
960 }
961
962 /* Keep aggregating only if stack says more data is coming
963 * and not doing mixed modes send and not flow blocked
964 */
965 xmit_more = netdev_xmit_more() &&
966 !packet->cp_partial &&
967 !netif_xmit_stopped(netdev_get_tx_queue(ndev, packet->q_idx));
968
969 if (section_index != NETVSC_INVALID_INDEX) {
970 netvsc_copy_to_send_buf(net_device,
971 section_index, msd_len,
972 packet, rndis_msg, pb, xmit_more);
973
974 packet->send_buf_index = section_index;
975
976 if (packet->cp_partial) {
977 packet->page_buf_cnt -= packet->rmsg_pgcnt;
978 packet->total_data_buflen = msd_len + packet->rmsg_size;
979 } else {
980 packet->page_buf_cnt = 0;
981 packet->total_data_buflen += msd_len;
982 }
983
984 if (msdp->pkt) {
985 packet->total_packets += msdp->pkt->total_packets;
986 packet->total_bytes += msdp->pkt->total_bytes;
987 }
988
989 if (msdp->skb)
990 dev_consume_skb_any(msdp->skb);
991
992 if (xmit_more) {
993 msdp->skb = skb;
994 msdp->pkt = packet;
995 msdp->count++;
996 } else {
997 cur_send = packet;
998 msdp->skb = NULL;
999 msdp->pkt = NULL;
1000 msdp->count = 0;
1001 }
1002 } else {
1003 move_pkt_msd(&msd_send, &msd_skb, msdp);
1004 cur_send = packet;
1005 }
1006
1007 if (msd_send) {
1008 int m_ret = netvsc_send_pkt(device, msd_send, net_device,
1009 NULL, msd_skb);
1010
1011 if (m_ret != 0) {
1012 netvsc_free_send_slot(net_device,
1013 msd_send->send_buf_index);
1014 dev_kfree_skb_any(msd_skb);
1015 }
1016 }
1017
1018 if (cur_send)
1019 ret = netvsc_send_pkt(device, cur_send, net_device, pb, skb);
1020
1021 if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
1022 netvsc_free_send_slot(net_device, section_index);
1023
1024 return ret;
1025 }
1026
1027 /* Send pending recv completions */
1028 static int send_recv_completions(struct net_device *ndev,
1029 struct netvsc_device *nvdev,
1030 struct netvsc_channel *nvchan)
1031 {
1032 struct multi_recv_comp *mrc = &nvchan->mrc;
1033 struct recv_comp_msg {
1034 struct nvsp_message_header hdr;
1035 u32 status;
1036 } __packed;
1037 struct recv_comp_msg msg = {
1038 .hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE,
1039 };
1040 int ret;
1041
1042 while (mrc->first != mrc->next) {
1043 const struct recv_comp_data *rcd
1044 = mrc->slots + mrc->first;
1045
1046 msg.status = rcd->status;
1047 ret = vmbus_sendpacket(nvchan->channel, &msg, sizeof(msg),
1048 rcd->tid, VM_PKT_COMP, 0);
1049 if (unlikely(ret)) {
1050 struct net_device_context *ndev_ctx = netdev_priv(ndev);
1051
1052 ++ndev_ctx->eth_stats.rx_comp_busy;
1053 return ret;
1054 }
1055
1056 if (++mrc->first == nvdev->recv_completion_cnt)
1057 mrc->first = 0;
1058 }
1059
1060 /* receive completion ring has been emptied */
1061 if (unlikely(nvdev->destroy))
1062 wake_up(&nvdev->wait_drain);
1063
1064 return 0;
1065 }
1066
1067 /* Count how many receive completions are outstanding */
1068 static void recv_comp_slot_avail(const struct netvsc_device *nvdev,
1069 const struct multi_recv_comp *mrc,
1070 u32 *filled, u32 *avail)
1071 {
1072 u32 count = nvdev->recv_completion_cnt;
1073
1074 if (mrc->next >= mrc->first)
1075 *filled = mrc->next - mrc->first;
1076 else
1077 *filled = (count - mrc->first) + mrc->next;
1078
1079 *avail = count - *filled - 1;
1080 }
1081
1082 /* Add receive complete to ring to send to host. */
1083 static void enq_receive_complete(struct net_device *ndev,
1084 struct netvsc_device *nvdev, u16 q_idx,
1085 u64 tid, u32 status)
1086 {
1087 struct netvsc_channel *nvchan = &nvdev->chan_table[q_idx];
1088 struct multi_recv_comp *mrc = &nvchan->mrc;
1089 struct recv_comp_data *rcd;
1090 u32 filled, avail;
1091
1092 recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1093
1094 if (unlikely(filled > NAPI_POLL_WEIGHT)) {
1095 send_recv_completions(ndev, nvdev, nvchan);
1096 recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1097 }
1098
1099 if (unlikely(!avail)) {
1100 netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
1101 q_idx, tid);
1102 return;
1103 }
1104
1105 rcd = mrc->slots + mrc->next;
1106 rcd->tid = tid;
1107 rcd->status = status;
1108
1109 if (++mrc->next == nvdev->recv_completion_cnt)
1110 mrc->next = 0;
1111 }
1112
1113 static int netvsc_receive(struct net_device *ndev,
1114 struct netvsc_device *net_device,
1115 struct netvsc_channel *nvchan,
1116 const struct vmpacket_descriptor *desc,
1117 const struct nvsp_message *nvsp)
1118 {
1119 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1120 struct vmbus_channel *channel = nvchan->channel;
1121 const struct vmtransfer_page_packet_header *vmxferpage_packet
1122 = container_of(desc, const struct vmtransfer_page_packet_header, d);
1123 u16 q_idx = channel->offermsg.offer.sub_channel_index;
1124 char *recv_buf = net_device->recv_buf;
1125 u32 status = NVSP_STAT_SUCCESS;
1126 int i;
1127 int count = 0;
1128
1129 /* Make sure this is a valid nvsp packet */
1130 if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {
1131 netif_err(net_device_ctx, rx_err, ndev,
1132 "Unknown nvsp packet type received %u\n",
1133 nvsp->hdr.msg_type);
1134 return 0;
1135 }
1136
1137 if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
1138 netif_err(net_device_ctx, rx_err, ndev,
1139 "Invalid xfer page set id - expecting %x got %x\n",
1140 NETVSC_RECEIVE_BUFFER_ID,
1141 vmxferpage_packet->xfer_pageset_id);
1142 return 0;
1143 }
1144
1145 count = vmxferpage_packet->range_cnt;
1146
1147 /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1148 for (i = 0; i < count; i++) {
1149 u32 offset = vmxferpage_packet->ranges[i].byte_offset;
1150 u32 buflen = vmxferpage_packet->ranges[i].byte_count;
1151 void *data;
1152 int ret;
1153
1154 if (unlikely(offset + buflen > net_device->recv_buf_size)) {
1155 nvchan->rsc.cnt = 0;
1156 status = NVSP_STAT_FAIL;
1157 netif_err(net_device_ctx, rx_err, ndev,
1158 "Packet offset:%u + len:%u too big\n",
1159 offset, buflen);
1160
1161 continue;
1162 }
1163
1164 data = recv_buf + offset;
1165
1166 nvchan->rsc.is_last = (i == count - 1);
1167
1168 trace_rndis_recv(ndev, q_idx, data);
1169
1170 /* Pass it to the upper layer */
1171 ret = rndis_filter_receive(ndev, net_device,
1172 nvchan, data, buflen);
1173
1174 if (unlikely(ret != NVSP_STAT_SUCCESS))
1175 status = NVSP_STAT_FAIL;
1176 }
1177
1178 enq_receive_complete(ndev, net_device, q_idx,
1179 vmxferpage_packet->d.trans_id, status);
1180
1181 return count;
1182 }
1183
1184 static void netvsc_send_table(struct net_device *ndev,
1185 struct netvsc_device *nvscdev,
1186 const struct nvsp_message *nvmsg,
1187 u32 msglen)
1188 {
1189 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1190 u32 count, offset, *tab;
1191 int i;
1192
1193 count = nvmsg->msg.v5_msg.send_table.count;
1194 offset = nvmsg->msg.v5_msg.send_table.offset;
1195
1196 if (count != VRSS_SEND_TAB_SIZE) {
1197 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1198 return;
1199 }
1200
1201 /* If negotiated version <= NVSP_PROTOCOL_VERSION_6, the offset may be
1202 * wrong due to a host bug. So fix the offset here.
1203 */
1204 if (nvscdev->nvsp_version <= NVSP_PROTOCOL_VERSION_6 &&
1205 msglen >= sizeof(struct nvsp_message_header) +
1206 sizeof(union nvsp_6_message_uber) + count * sizeof(u32))
1207 offset = sizeof(struct nvsp_message_header) +
1208 sizeof(union nvsp_6_message_uber);
1209
1210 /* Boundary check for all versions */
1211 if (offset > msglen - count * sizeof(u32)) {
1212 netdev_err(ndev, "Received send-table offset too big:%u\n",
1213 offset);
1214 return;
1215 }
1216
1217 tab = (void *)nvmsg + offset;
1218
1219 for (i = 0; i < count; i++)
1220 net_device_ctx->tx_table[i] = tab[i];
1221 }
1222
1223 static void netvsc_send_vf(struct net_device *ndev,
1224 const struct nvsp_message *nvmsg)
1225 {
1226 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1227
1228 net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1229 net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1230 netdev_info(ndev, "VF slot %u %s\n",
1231 net_device_ctx->vf_serial,
1232 net_device_ctx->vf_alloc ? "added" : "removed");
1233 }
1234
1235 static void netvsc_receive_inband(struct net_device *ndev,
1236 struct netvsc_device *nvscdev,
1237 const struct nvsp_message *nvmsg,
1238 u32 msglen)
1239 {
1240 switch (nvmsg->hdr.msg_type) {
1241 case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1242 netvsc_send_table(ndev, nvscdev, nvmsg, msglen);
1243 break;
1244
1245 case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1246 netvsc_send_vf(ndev, nvmsg);
1247 break;
1248 }
1249 }
1250
1251 static int netvsc_process_raw_pkt(struct hv_device *device,
1252 struct netvsc_channel *nvchan,
1253 struct netvsc_device *net_device,
1254 struct net_device *ndev,
1255 const struct vmpacket_descriptor *desc,
1256 int budget)
1257 {
1258 struct vmbus_channel *channel = nvchan->channel;
1259 const struct nvsp_message *nvmsg = hv_pkt_data(desc);
1260 u32 msglen = hv_pkt_datalen(desc);
1261
1262 trace_nvsp_recv(ndev, channel, nvmsg);
1263
1264 switch (desc->type) {
1265 case VM_PKT_COMP:
1266 netvsc_send_completion(ndev, net_device, channel,
1267 desc, budget);
1268 break;
1269
1270 case VM_PKT_DATA_USING_XFER_PAGES:
1271 return netvsc_receive(ndev, net_device, nvchan,
1272 desc, nvmsg);
1273 break;
1274
1275 case VM_PKT_DATA_INBAND:
1276 netvsc_receive_inband(ndev, net_device, nvmsg, msglen);
1277 break;
1278
1279 default:
1280 netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1281 desc->type, desc->trans_id);
1282 break;
1283 }
1284
1285 return 0;
1286 }
1287
1288 static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
1289 {
1290 struct vmbus_channel *primary = channel->primary_channel;
1291
1292 return primary ? primary->device_obj : channel->device_obj;
1293 }
1294
1295 /* Network processing softirq
1296 * Process data in incoming ring buffer from host
1297 * Stops when ring is empty or budget is met or exceeded.
1298 */
1299 int netvsc_poll(struct napi_struct *napi, int budget)
1300 {
1301 struct netvsc_channel *nvchan
1302 = container_of(napi, struct netvsc_channel, napi);
1303 struct netvsc_device *net_device = nvchan->net_device;
1304 struct vmbus_channel *channel = nvchan->channel;
1305 struct hv_device *device = netvsc_channel_to_device(channel);
1306 struct net_device *ndev = hv_get_drvdata(device);
1307 int work_done = 0;
1308 int ret;
1309
1310 /* If starting a new interval */
1311 if (!nvchan->desc)
1312 nvchan->desc = hv_pkt_iter_first(channel);
1313
1314 while (nvchan->desc && work_done < budget) {
1315 work_done += netvsc_process_raw_pkt(device, nvchan, net_device,
1316 ndev, nvchan->desc, budget);
1317 nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
1318 }
1319
1320 /* Send any pending receive completions */
1321 ret = send_recv_completions(ndev, net_device, nvchan);
1322
1323 /* If it did not exhaust NAPI budget this time
1324 * and not doing busy poll
1325 * then re-enable host interrupts
1326 * and reschedule if ring is not empty
1327 * or sending receive completion failed.
1328 */
1329 if (work_done < budget &&
1330 napi_complete_done(napi, work_done) &&
1331 (ret || hv_end_read(&channel->inbound)) &&
1332 napi_schedule_prep(napi)) {
1333 hv_begin_read(&channel->inbound);
1334 __napi_schedule(napi);
1335 }
1336
1337 /* Driver may overshoot since multiple packets per descriptor */
1338 return min(work_done, budget);
1339 }
1340
1341 /* Call back when data is available in host ring buffer.
1342 * Processing is deferred until network softirq (NAPI)
1343 */
1344 void netvsc_channel_cb(void *context)
1345 {
1346 struct netvsc_channel *nvchan = context;
1347 struct vmbus_channel *channel = nvchan->channel;
1348 struct hv_ring_buffer_info *rbi = &channel->inbound;
1349
1350 /* preload first vmpacket descriptor */
1351 prefetch(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
1352
1353 if (napi_schedule_prep(&nvchan->napi)) {
1354 /* disable interrupts from host */
1355 hv_begin_read(rbi);
1356
1357 __napi_schedule_irqoff(&nvchan->napi);
1358 }
1359 }
1360
1361 /*
1362 * netvsc_device_add - Callback when the device belonging to this
1363 * driver is added
1364 */
1365 struct netvsc_device *netvsc_device_add(struct hv_device *device,
1366 const struct netvsc_device_info *device_info)
1367 {
1368 int i, ret = 0;
1369 struct netvsc_device *net_device;
1370 struct net_device *ndev = hv_get_drvdata(device);
1371 struct net_device_context *net_device_ctx = netdev_priv(ndev);
1372
1373 net_device = alloc_net_device();
1374 if (!net_device)
1375 return ERR_PTR(-ENOMEM);
1376
1377 for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
1378 net_device_ctx->tx_table[i] = 0;
1379
1380 /* Because the device uses NAPI, all the interrupt batching and
1381 * control is done via Net softirq, not the channel handling
1382 */
1383 set_channel_read_mode(device->channel, HV_CALL_ISR);
1384
1385 /* If we're reopening the device we may have multiple queues, fill the
1386 * chn_table with the default channel to use it before subchannels are
1387 * opened.
1388 * Initialize the channel state before we open;
1389 * we can be interrupted as soon as we open the channel.
1390 */
1391
1392 for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
1393 struct netvsc_channel *nvchan = &net_device->chan_table[i];
1394
1395 nvchan->channel = device->channel;
1396 nvchan->net_device = net_device;
1397 u64_stats_init(&nvchan->tx_stats.syncp);
1398 u64_stats_init(&nvchan->rx_stats.syncp);
1399
1400 ret = xdp_rxq_info_reg(&nvchan->xdp_rxq, ndev, i);
1401
1402 if (ret) {
1403 netdev_err(ndev, "xdp_rxq_info_reg fail: %d\n", ret);
1404 goto cleanup2;
1405 }
1406
1407 ret = xdp_rxq_info_reg_mem_model(&nvchan->xdp_rxq,
1408 MEM_TYPE_PAGE_SHARED, NULL);
1409
1410 if (ret) {
1411 netdev_err(ndev, "xdp reg_mem_model fail: %d\n", ret);
1412 goto cleanup2;
1413 }
1414 }
1415
1416 /* Enable NAPI handler before init callbacks */
1417 netif_napi_add(ndev, &net_device->chan_table[0].napi,
1418 netvsc_poll, NAPI_POLL_WEIGHT);
1419
1420 /* Open the channel */
1421 ret = vmbus_open(device->channel, netvsc_ring_bytes,
1422 netvsc_ring_bytes, NULL, 0,
1423 netvsc_channel_cb, net_device->chan_table);
1424
1425 if (ret != 0) {
1426 netdev_err(ndev, "unable to open channel: %d\n", ret);
1427 goto cleanup;
1428 }
1429
1430 /* Channel is opened */
1431 netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
1432
1433 napi_enable(&net_device->chan_table[0].napi);
1434
1435 /* Connect with the NetVsp */
1436 ret = netvsc_connect_vsp(device, net_device, device_info);
1437 if (ret != 0) {
1438 netdev_err(ndev,
1439 "unable to connect to NetVSP - %d\n", ret);
1440 goto close;
1441 }
1442
1443 /* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1444 * populated.
1445 */
1446 rcu_assign_pointer(net_device_ctx->nvdev, net_device);
1447
1448 return net_device;
1449
1450 close:
1451 RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
1452 napi_disable(&net_device->chan_table[0].napi);
1453
1454 /* Now, we can close the channel safely */
1455 vmbus_close(device->channel);
1456
1457 cleanup:
1458 netif_napi_del(&net_device->chan_table[0].napi);
1459
1460 cleanup2:
1461 free_netvsc_device(&net_device->rcu);
1462
1463 return ERR_PTR(ret);
1464 }
Linux with added FPC-III support