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v4.17
 
   1/*
   2 * Copyright (c) 2009, Microsoft Corporation.
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms and conditions of the GNU General Public License,
   6 * version 2, as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope it will be useful, but WITHOUT
   9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11 * more details.
  12 *
  13 * You should have received a copy of the GNU General Public License along with
  14 * this program; if not, see <http://www.gnu.org/licenses/>.
  15 *
  16 * Authors:
  17 *   Haiyang Zhang <haiyangz@microsoft.com>
  18 *   Hank Janssen  <hjanssen@microsoft.com>
  19 */
  20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22#include <linux/kernel.h>
  23#include <linux/sched.h>
  24#include <linux/wait.h>
  25#include <linux/mm.h>
  26#include <linux/delay.h>
  27#include <linux/io.h>
  28#include <linux/slab.h>
  29#include <linux/netdevice.h>
  30#include <linux/if_ether.h>
  31#include <linux/vmalloc.h>
  32#include <linux/rtnetlink.h>
  33#include <linux/prefetch.h>
  34#include <linux/reciprocal_div.h>
  35
  36#include <asm/sync_bitops.h>
  37
  38#include "hyperv_net.h"
  39#include "netvsc_trace.h"
  40
  41/*
  42 * Switch the data path from the synthetic interface to the VF
  43 * interface.
  44 */
  45void netvsc_switch_datapath(struct net_device *ndev, bool vf)
  46{
  47	struct net_device_context *net_device_ctx = netdev_priv(ndev);
  48	struct hv_device *dev = net_device_ctx->device_ctx;
  49	struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev);
  50	struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;
  51
  52	memset(init_pkt, 0, sizeof(struct nvsp_message));
  53	init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;
  54	if (vf)
  55		init_pkt->msg.v4_msg.active_dp.active_datapath =
  56			NVSP_DATAPATH_VF;
  57	else
  58		init_pkt->msg.v4_msg.active_dp.active_datapath =
  59			NVSP_DATAPATH_SYNTHETIC;
  60
  61	trace_nvsp_send(ndev, init_pkt);
  62
  63	vmbus_sendpacket(dev->channel, init_pkt,
  64			       sizeof(struct nvsp_message),
  65			       (unsigned long)init_pkt,
  66			       VM_PKT_DATA_INBAND, 0);
  67}
  68
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  69static struct netvsc_device *alloc_net_device(void)
  70{
  71	struct netvsc_device *net_device;
  72
  73	net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  74	if (!net_device)
  75		return NULL;
  76
  77	init_waitqueue_head(&net_device->wait_drain);
  78	net_device->destroy = false;
 
  79
  80	net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
  81	net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
  82
  83	init_completion(&net_device->channel_init_wait);
  84	init_waitqueue_head(&net_device->subchan_open);
  85	INIT_WORK(&net_device->subchan_work, rndis_set_subchannel);
  86
  87	return net_device;
  88}
  89
  90static void free_netvsc_device(struct rcu_head *head)
  91{
  92	struct netvsc_device *nvdev
  93		= container_of(head, struct netvsc_device, rcu);
  94	int i;
  95
  96	kfree(nvdev->extension);
  97	vfree(nvdev->recv_buf);
  98	vfree(nvdev->send_buf);
  99	kfree(nvdev->send_section_map);
 100
 101	for (i = 0; i < VRSS_CHANNEL_MAX; i++)
 102		vfree(nvdev->chan_table[i].mrc.slots);
 103
 104	kfree(nvdev);
 105}
 106
 107static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
 108{
 109	call_rcu(&nvdev->rcu, free_netvsc_device);
 110}
 111
 112static void netvsc_revoke_recv_buf(struct hv_device *device,
 113				   struct netvsc_device *net_device,
 114				   struct net_device *ndev)
 115{
 116	struct nvsp_message *revoke_packet;
 117	int ret;
 118
 119	/*
 120	 * If we got a section count, it means we received a
 121	 * SendReceiveBufferComplete msg (ie sent
 122	 * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 123	 * to send a revoke msg here
 124	 */
 125	if (net_device->recv_section_cnt) {
 126		/* Send the revoke receive buffer */
 127		revoke_packet = &net_device->revoke_packet;
 128		memset(revoke_packet, 0, sizeof(struct nvsp_message));
 129
 130		revoke_packet->hdr.msg_type =
 131			NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 132		revoke_packet->msg.v1_msg.
 133		revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 134
 135		trace_nvsp_send(ndev, revoke_packet);
 136
 137		ret = vmbus_sendpacket(device->channel,
 138				       revoke_packet,
 139				       sizeof(struct nvsp_message),
 140				       (unsigned long)revoke_packet,
 141				       VM_PKT_DATA_INBAND, 0);
 142		/* If the failure is because the channel is rescinded;
 143		 * ignore the failure since we cannot send on a rescinded
 144		 * channel. This would allow us to properly cleanup
 145		 * even when the channel is rescinded.
 146		 */
 147		if (device->channel->rescind)
 148			ret = 0;
 149		/*
 150		 * If we failed here, we might as well return and
 151		 * have a leak rather than continue and a bugchk
 152		 */
 153		if (ret != 0) {
 154			netdev_err(ndev, "unable to send "
 155				"revoke receive buffer to netvsp\n");
 156			return;
 157		}
 158		net_device->recv_section_cnt = 0;
 159	}
 160}
 161
 162static void netvsc_revoke_send_buf(struct hv_device *device,
 163				   struct netvsc_device *net_device,
 164				   struct net_device *ndev)
 165{
 166	struct nvsp_message *revoke_packet;
 167	int ret;
 168
 169	/* Deal with the send buffer we may have setup.
 170	 * If we got a  send section size, it means we received a
 171	 * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
 172	 * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
 173	 * to send a revoke msg here
 174	 */
 175	if (net_device->send_section_cnt) {
 176		/* Send the revoke receive buffer */
 177		revoke_packet = &net_device->revoke_packet;
 178		memset(revoke_packet, 0, sizeof(struct nvsp_message));
 179
 180		revoke_packet->hdr.msg_type =
 181			NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
 182		revoke_packet->msg.v1_msg.revoke_send_buf.id =
 183			NETVSC_SEND_BUFFER_ID;
 184
 185		trace_nvsp_send(ndev, revoke_packet);
 186
 187		ret = vmbus_sendpacket(device->channel,
 188				       revoke_packet,
 189				       sizeof(struct nvsp_message),
 190				       (unsigned long)revoke_packet,
 191				       VM_PKT_DATA_INBAND, 0);
 192
 193		/* If the failure is because the channel is rescinded;
 194		 * ignore the failure since we cannot send on a rescinded
 195		 * channel. This would allow us to properly cleanup
 196		 * even when the channel is rescinded.
 197		 */
 198		if (device->channel->rescind)
 199			ret = 0;
 200
 201		/* If we failed here, we might as well return and
 202		 * have a leak rather than continue and a bugchk
 203		 */
 204		if (ret != 0) {
 205			netdev_err(ndev, "unable to send "
 206				   "revoke send buffer to netvsp\n");
 207			return;
 208		}
 209		net_device->send_section_cnt = 0;
 210	}
 211}
 212
 213static void netvsc_teardown_recv_gpadl(struct hv_device *device,
 214				       struct netvsc_device *net_device,
 215				       struct net_device *ndev)
 216{
 217	int ret;
 218
 219	if (net_device->recv_buf_gpadl_handle) {
 220		ret = vmbus_teardown_gpadl(device->channel,
 221					   net_device->recv_buf_gpadl_handle);
 222
 223		/* If we failed here, we might as well return and have a leak
 224		 * rather than continue and a bugchk
 225		 */
 226		if (ret != 0) {
 227			netdev_err(ndev,
 228				   "unable to teardown receive buffer's gpadl\n");
 229			return;
 230		}
 231		net_device->recv_buf_gpadl_handle = 0;
 232	}
 233}
 234
 235static void netvsc_teardown_send_gpadl(struct hv_device *device,
 236				       struct netvsc_device *net_device,
 237				       struct net_device *ndev)
 238{
 239	int ret;
 240
 241	if (net_device->send_buf_gpadl_handle) {
 242		ret = vmbus_teardown_gpadl(device->channel,
 243					   net_device->send_buf_gpadl_handle);
 244
 245		/* If we failed here, we might as well return and have a leak
 246		 * rather than continue and a bugchk
 247		 */
 248		if (ret != 0) {
 249			netdev_err(ndev,
 250				   "unable to teardown send buffer's gpadl\n");
 251			return;
 252		}
 253		net_device->send_buf_gpadl_handle = 0;
 254	}
 255}
 256
 257int netvsc_alloc_recv_comp_ring(struct netvsc_device *net_device, u32 q_idx)
 258{
 259	struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
 260	int node = cpu_to_node(nvchan->channel->target_cpu);
 261	size_t size;
 262
 263	size = net_device->recv_completion_cnt * sizeof(struct recv_comp_data);
 264	nvchan->mrc.slots = vzalloc_node(size, node);
 265	if (!nvchan->mrc.slots)
 266		nvchan->mrc.slots = vzalloc(size);
 267
 268	return nvchan->mrc.slots ? 0 : -ENOMEM;
 269}
 270
 271static int netvsc_init_buf(struct hv_device *device,
 272			   struct netvsc_device *net_device,
 273			   const struct netvsc_device_info *device_info)
 274{
 275	struct nvsp_1_message_send_receive_buffer_complete *resp;
 276	struct net_device *ndev = hv_get_drvdata(device);
 277	struct nvsp_message *init_packet;
 278	unsigned int buf_size;
 279	size_t map_words;
 280	int ret = 0;
 281
 282	/* Get receive buffer area. */
 283	buf_size = device_info->recv_sections * device_info->recv_section_size;
 284	buf_size = roundup(buf_size, PAGE_SIZE);
 285
 286	/* Legacy hosts only allow smaller receive buffer */
 287	if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
 288		buf_size = min_t(unsigned int, buf_size,
 289				 NETVSC_RECEIVE_BUFFER_SIZE_LEGACY);
 290
 291	net_device->recv_buf = vzalloc(buf_size);
 292	if (!net_device->recv_buf) {
 293		netdev_err(ndev,
 294			   "unable to allocate receive buffer of size %u\n",
 295			   buf_size);
 296		ret = -ENOMEM;
 297		goto cleanup;
 298	}
 299
 300	net_device->recv_buf_size = buf_size;
 301
 302	/*
 303	 * Establish the gpadl handle for this buffer on this
 304	 * channel.  Note: This call uses the vmbus connection rather
 305	 * than the channel to establish the gpadl handle.
 306	 */
 307	ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 308				    buf_size,
 309				    &net_device->recv_buf_gpadl_handle);
 310	if (ret != 0) {
 311		netdev_err(ndev,
 312			"unable to establish receive buffer's gpadl\n");
 313		goto cleanup;
 314	}
 315
 316	/* Notify the NetVsp of the gpadl handle */
 317	init_packet = &net_device->channel_init_pkt;
 318	memset(init_packet, 0, sizeof(struct nvsp_message));
 319	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 320	init_packet->msg.v1_msg.send_recv_buf.
 321		gpadl_handle = net_device->recv_buf_gpadl_handle;
 322	init_packet->msg.v1_msg.
 323		send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 324
 325	trace_nvsp_send(ndev, init_packet);
 326
 327	/* Send the gpadl notification request */
 328	ret = vmbus_sendpacket(device->channel, init_packet,
 329			       sizeof(struct nvsp_message),
 330			       (unsigned long)init_packet,
 331			       VM_PKT_DATA_INBAND,
 332			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 333	if (ret != 0) {
 334		netdev_err(ndev,
 335			"unable to send receive buffer's gpadl to netvsp\n");
 336		goto cleanup;
 337	}
 338
 339	wait_for_completion(&net_device->channel_init_wait);
 340
 341	/* Check the response */
 342	resp = &init_packet->msg.v1_msg.send_recv_buf_complete;
 343	if (resp->status != NVSP_STAT_SUCCESS) {
 344		netdev_err(ndev,
 345			   "Unable to complete receive buffer initialization with NetVsp - status %d\n",
 346			   resp->status);
 347		ret = -EINVAL;
 348		goto cleanup;
 349	}
 350
 351	/* Parse the response */
 352	netdev_dbg(ndev, "Receive sections: %u sub_allocs: size %u count: %u\n",
 353		   resp->num_sections, resp->sections[0].sub_alloc_size,
 354		   resp->sections[0].num_sub_allocs);
 355
 356	/* There should only be one section for the entire receive buffer */
 357	if (resp->num_sections != 1 || resp->sections[0].offset != 0) {
 358		ret = -EINVAL;
 359		goto cleanup;
 360	}
 361
 362	net_device->recv_section_size = resp->sections[0].sub_alloc_size;
 363	net_device->recv_section_cnt = resp->sections[0].num_sub_allocs;
 364
 365	/* Setup receive completion ring */
 366	net_device->recv_completion_cnt
 367		= round_up(net_device->recv_section_cnt + 1,
 368			   PAGE_SIZE / sizeof(u64));
 369	ret = netvsc_alloc_recv_comp_ring(net_device, 0);
 370	if (ret)
 371		goto cleanup;
 372
 373	/* Now setup the send buffer. */
 374	buf_size = device_info->send_sections * device_info->send_section_size;
 375	buf_size = round_up(buf_size, PAGE_SIZE);
 376
 377	net_device->send_buf = vzalloc(buf_size);
 378	if (!net_device->send_buf) {
 379		netdev_err(ndev, "unable to allocate send buffer of size %u\n",
 380			   buf_size);
 381		ret = -ENOMEM;
 382		goto cleanup;
 383	}
 384
 385	/* Establish the gpadl handle for this buffer on this
 386	 * channel.  Note: This call uses the vmbus connection rather
 387	 * than the channel to establish the gpadl handle.
 388	 */
 389	ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
 390				    buf_size,
 391				    &net_device->send_buf_gpadl_handle);
 392	if (ret != 0) {
 393		netdev_err(ndev,
 394			   "unable to establish send buffer's gpadl\n");
 395		goto cleanup;
 396	}
 397
 398	/* Notify the NetVsp of the gpadl handle */
 399	init_packet = &net_device->channel_init_pkt;
 400	memset(init_packet, 0, sizeof(struct nvsp_message));
 401	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
 402	init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
 403		net_device->send_buf_gpadl_handle;
 404	init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
 405
 406	trace_nvsp_send(ndev, init_packet);
 407
 408	/* Send the gpadl notification request */
 409	ret = vmbus_sendpacket(device->channel, init_packet,
 410			       sizeof(struct nvsp_message),
 411			       (unsigned long)init_packet,
 412			       VM_PKT_DATA_INBAND,
 413			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 414	if (ret != 0) {
 415		netdev_err(ndev,
 416			   "unable to send send buffer's gpadl to netvsp\n");
 417		goto cleanup;
 418	}
 419
 420	wait_for_completion(&net_device->channel_init_wait);
 421
 422	/* Check the response */
 423	if (init_packet->msg.v1_msg.
 424	    send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
 425		netdev_err(ndev, "Unable to complete send buffer "
 426			   "initialization with NetVsp - status %d\n",
 427			   init_packet->msg.v1_msg.
 428			   send_send_buf_complete.status);
 429		ret = -EINVAL;
 430		goto cleanup;
 431	}
 432
 433	/* Parse the response */
 434	net_device->send_section_size = init_packet->msg.
 435				v1_msg.send_send_buf_complete.section_size;
 436
 437	/* Section count is simply the size divided by the section size. */
 438	net_device->send_section_cnt = buf_size / net_device->send_section_size;
 439
 440	netdev_dbg(ndev, "Send section size: %d, Section count:%d\n",
 441		   net_device->send_section_size, net_device->send_section_cnt);
 442
 443	/* Setup state for managing the send buffer. */
 444	map_words = DIV_ROUND_UP(net_device->send_section_cnt, BITS_PER_LONG);
 445
 446	net_device->send_section_map = kcalloc(map_words, sizeof(ulong), GFP_KERNEL);
 447	if (net_device->send_section_map == NULL) {
 448		ret = -ENOMEM;
 449		goto cleanup;
 450	}
 451
 452	goto exit;
 453
 454cleanup:
 455	netvsc_revoke_recv_buf(device, net_device, ndev);
 456	netvsc_revoke_send_buf(device, net_device, ndev);
 457	netvsc_teardown_recv_gpadl(device, net_device, ndev);
 458	netvsc_teardown_send_gpadl(device, net_device, ndev);
 459
 460exit:
 461	return ret;
 462}
 463
 464/* Negotiate NVSP protocol version */
 465static int negotiate_nvsp_ver(struct hv_device *device,
 466			      struct netvsc_device *net_device,
 467			      struct nvsp_message *init_packet,
 468			      u32 nvsp_ver)
 469{
 470	struct net_device *ndev = hv_get_drvdata(device);
 471	int ret;
 472
 473	memset(init_packet, 0, sizeof(struct nvsp_message));
 474	init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 475	init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 476	init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 477	trace_nvsp_send(ndev, init_packet);
 478
 479	/* Send the init request */
 480	ret = vmbus_sendpacket(device->channel, init_packet,
 481			       sizeof(struct nvsp_message),
 482			       (unsigned long)init_packet,
 483			       VM_PKT_DATA_INBAND,
 484			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 485
 486	if (ret != 0)
 487		return ret;
 488
 489	wait_for_completion(&net_device->channel_init_wait);
 490
 491	if (init_packet->msg.init_msg.init_complete.status !=
 492	    NVSP_STAT_SUCCESS)
 493		return -EINVAL;
 494
 495	if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
 496		return 0;
 497
 498	/* NVSPv2 or later: Send NDIS config */
 499	memset(init_packet, 0, sizeof(struct nvsp_message));
 500	init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 501	init_packet->msg.v2_msg.send_ndis_config.mtu = ndev->mtu + ETH_HLEN;
 502	init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 503
 504	if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
 505		init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
 506
 507		/* Teaming bit is needed to receive link speed updates */
 508		init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
 509	}
 510
 
 
 
 511	trace_nvsp_send(ndev, init_packet);
 512
 513	ret = vmbus_sendpacket(device->channel, init_packet,
 514				sizeof(struct nvsp_message),
 515				(unsigned long)init_packet,
 516				VM_PKT_DATA_INBAND, 0);
 517
 518	return ret;
 519}
 520
 521static int netvsc_connect_vsp(struct hv_device *device,
 522			      struct netvsc_device *net_device,
 523			      const struct netvsc_device_info *device_info)
 524{
 525	struct net_device *ndev = hv_get_drvdata(device);
 526	static const u32 ver_list[] = {
 527		NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
 528		NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5
 
 529	};
 530	struct nvsp_message *init_packet;
 531	int ndis_version, i, ret;
 532
 533	init_packet = &net_device->channel_init_pkt;
 534
 535	/* Negotiate the latest NVSP protocol supported */
 536	for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
 537		if (negotiate_nvsp_ver(device, net_device, init_packet,
 538				       ver_list[i])  == 0) {
 539			net_device->nvsp_version = ver_list[i];
 540			break;
 541		}
 542
 543	if (i < 0) {
 544		ret = -EPROTO;
 545		goto cleanup;
 546	}
 547
 548	pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 549
 550	/* Send the ndis version */
 551	memset(init_packet, 0, sizeof(struct nvsp_message));
 552
 553	if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
 554		ndis_version = 0x00060001;
 555	else
 556		ndis_version = 0x0006001e;
 557
 558	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 559	init_packet->msg.v1_msg.
 560		send_ndis_ver.ndis_major_ver =
 561				(ndis_version & 0xFFFF0000) >> 16;
 562	init_packet->msg.v1_msg.
 563		send_ndis_ver.ndis_minor_ver =
 564				ndis_version & 0xFFFF;
 565
 566	trace_nvsp_send(ndev, init_packet);
 567
 568	/* Send the init request */
 569	ret = vmbus_sendpacket(device->channel, init_packet,
 570				sizeof(struct nvsp_message),
 571				(unsigned long)init_packet,
 572				VM_PKT_DATA_INBAND, 0);
 573	if (ret != 0)
 574		goto cleanup;
 575
 576
 577	ret = netvsc_init_buf(device, net_device, device_info);
 578
 579cleanup:
 580	return ret;
 581}
 582
 583/*
 584 * netvsc_device_remove - Callback when the root bus device is removed
 585 */
 586void netvsc_device_remove(struct hv_device *device)
 587{
 588	struct net_device *ndev = hv_get_drvdata(device);
 589	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 590	struct netvsc_device *net_device
 591		= rtnl_dereference(net_device_ctx->nvdev);
 592	int i;
 593
 594	/*
 595	 * Revoke receive buffer. If host is pre-Win2016 then tear down
 596	 * receive buffer GPADL. Do the same for send buffer.
 597	 */
 598	netvsc_revoke_recv_buf(device, net_device, ndev);
 599	if (vmbus_proto_version < VERSION_WIN10)
 600		netvsc_teardown_recv_gpadl(device, net_device, ndev);
 601
 602	netvsc_revoke_send_buf(device, net_device, ndev);
 603	if (vmbus_proto_version < VERSION_WIN10)
 604		netvsc_teardown_send_gpadl(device, net_device, ndev);
 605
 606	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
 607
 608	/* And disassociate NAPI context from device */
 609	for (i = 0; i < net_device->num_chn; i++)
 610		netif_napi_del(&net_device->chan_table[i].napi);
 611
 612	/*
 613	 * At this point, no one should be accessing net_device
 614	 * except in here
 615	 */
 616	netdev_dbg(ndev, "net device safe to remove\n");
 617
 618	/* Now, we can close the channel safely */
 619	vmbus_close(device->channel);
 620
 621	/*
 622	 * If host is Win2016 or higher then we do the GPADL tear down
 623	 * here after VMBus is closed.
 624	*/
 625	if (vmbus_proto_version >= VERSION_WIN10) {
 626		netvsc_teardown_recv_gpadl(device, net_device, ndev);
 627		netvsc_teardown_send_gpadl(device, net_device, ndev);
 628	}
 629
 630	/* Release all resources */
 631	free_netvsc_device_rcu(net_device);
 632}
 633
 634#define RING_AVAIL_PERCENT_HIWATER 20
 635#define RING_AVAIL_PERCENT_LOWATER 10
 636
 637/*
 638 * Get the percentage of available bytes to write in the ring.
 639 * The return value is in range from 0 to 100.
 640 */
 641static u32 hv_ringbuf_avail_percent(const struct hv_ring_buffer_info *ring_info)
 642{
 643	u32 avail_write = hv_get_bytes_to_write(ring_info);
 644
 645	return reciprocal_divide(avail_write  * 100, netvsc_ring_reciprocal);
 646}
 647
 648static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 649					 u32 index)
 650{
 651	sync_change_bit(index, net_device->send_section_map);
 652}
 653
 654static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 655				    struct vmbus_channel *incoming_channel,
 656				    struct hv_device *device,
 657				    const struct vmpacket_descriptor *desc,
 658				    int budget)
 659{
 660	struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
 661	struct net_device *ndev = hv_get_drvdata(device);
 662	struct net_device_context *ndev_ctx = netdev_priv(ndev);
 663	struct vmbus_channel *channel = device->channel;
 664	u16 q_idx = 0;
 665	int queue_sends;
 666
 667	/* Notify the layer above us */
 668	if (likely(skb)) {
 669		const struct hv_netvsc_packet *packet
 670			= (struct hv_netvsc_packet *)skb->cb;
 671		u32 send_index = packet->send_buf_index;
 672		struct netvsc_stats *tx_stats;
 673
 674		if (send_index != NETVSC_INVALID_INDEX)
 675			netvsc_free_send_slot(net_device, send_index);
 676		q_idx = packet->q_idx;
 677		channel = incoming_channel;
 678
 679		tx_stats = &net_device->chan_table[q_idx].tx_stats;
 680
 681		u64_stats_update_begin(&tx_stats->syncp);
 682		tx_stats->packets += packet->total_packets;
 683		tx_stats->bytes += packet->total_bytes;
 684		u64_stats_update_end(&tx_stats->syncp);
 685
 686		napi_consume_skb(skb, budget);
 687	}
 688
 689	queue_sends =
 690		atomic_dec_return(&net_device->chan_table[q_idx].queue_sends);
 691
 692	if (unlikely(net_device->destroy)) {
 693		if (queue_sends == 0)
 694			wake_up(&net_device->wait_drain);
 695	} else {
 696		struct netdev_queue *txq = netdev_get_tx_queue(ndev, q_idx);
 697
 698		if (netif_tx_queue_stopped(txq) &&
 699		    (hv_ringbuf_avail_percent(&channel->outbound) > RING_AVAIL_PERCENT_HIWATER ||
 700		     queue_sends < 1)) {
 701			netif_tx_wake_queue(txq);
 702			ndev_ctx->eth_stats.wake_queue++;
 703		}
 704	}
 705}
 706
 707static void netvsc_send_completion(struct netvsc_device *net_device,
 
 708				   struct vmbus_channel *incoming_channel,
 709				   struct hv_device *device,
 710				   const struct vmpacket_descriptor *desc,
 711				   int budget)
 712{
 713	struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
 714	struct net_device *ndev = hv_get_drvdata(device);
 715
 716	switch (nvsp_packet->hdr.msg_type) {
 717	case NVSP_MSG_TYPE_INIT_COMPLETE:
 718	case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
 719	case NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE:
 720	case NVSP_MSG5_TYPE_SUBCHANNEL:
 721		/* Copy the response back */
 722		memcpy(&net_device->channel_init_pkt, nvsp_packet,
 723		       sizeof(struct nvsp_message));
 724		complete(&net_device->channel_init_wait);
 725		break;
 726
 727	case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
 728		netvsc_send_tx_complete(net_device, incoming_channel,
 729					device, desc, budget);
 730		break;
 731
 732	default:
 733		netdev_err(ndev,
 734			   "Unknown send completion type %d received!!\n",
 735			   nvsp_packet->hdr.msg_type);
 736	}
 737}
 738
 739static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 740{
 741	unsigned long *map_addr = net_device->send_section_map;
 742	unsigned int i;
 743
 744	for_each_clear_bit(i, map_addr, net_device->send_section_cnt) {
 745		if (sync_test_and_set_bit(i, map_addr) == 0)
 746			return i;
 747	}
 748
 749	return NETVSC_INVALID_INDEX;
 750}
 751
 752static void netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 753				    unsigned int section_index,
 754				    u32 pend_size,
 755				    struct hv_netvsc_packet *packet,
 756				    struct rndis_message *rndis_msg,
 757				    struct hv_page_buffer *pb,
 758				    bool xmit_more)
 759{
 760	char *start = net_device->send_buf;
 761	char *dest = start + (section_index * net_device->send_section_size)
 762		     + pend_size;
 763	int i;
 764	u32 padding = 0;
 765	u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 766		packet->page_buf_cnt;
 767	u32 remain;
 768
 769	/* Add padding */
 770	remain = packet->total_data_buflen & (net_device->pkt_align - 1);
 771	if (xmit_more && remain) {
 772		padding = net_device->pkt_align - remain;
 773		rndis_msg->msg_len += padding;
 774		packet->total_data_buflen += padding;
 775	}
 776
 777	for (i = 0; i < page_count; i++) {
 778		char *src = phys_to_virt(pb[i].pfn << PAGE_SHIFT);
 779		u32 offset = pb[i].offset;
 780		u32 len = pb[i].len;
 781
 782		memcpy(dest, (src + offset), len);
 783		dest += len;
 784	}
 785
 786	if (padding)
 787		memset(dest, 0, padding);
 788}
 789
 790static inline int netvsc_send_pkt(
 791	struct hv_device *device,
 792	struct hv_netvsc_packet *packet,
 793	struct netvsc_device *net_device,
 794	struct hv_page_buffer *pb,
 795	struct sk_buff *skb)
 796{
 797	struct nvsp_message nvmsg;
 798	struct nvsp_1_message_send_rndis_packet *rpkt =
 799		&nvmsg.msg.v1_msg.send_rndis_pkt;
 800	struct netvsc_channel * const nvchan =
 801		&net_device->chan_table[packet->q_idx];
 802	struct vmbus_channel *out_channel = nvchan->channel;
 803	struct net_device *ndev = hv_get_drvdata(device);
 804	struct net_device_context *ndev_ctx = netdev_priv(ndev);
 805	struct netdev_queue *txq = netdev_get_tx_queue(ndev, packet->q_idx);
 806	u64 req_id;
 807	int ret;
 808	u32 ring_avail = hv_ringbuf_avail_percent(&out_channel->outbound);
 809
 810	nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 811	if (skb)
 812		rpkt->channel_type = 0;		/* 0 is RMC_DATA */
 813	else
 814		rpkt->channel_type = 1;		/* 1 is RMC_CONTROL */
 815
 816	rpkt->send_buf_section_index = packet->send_buf_index;
 817	if (packet->send_buf_index == NETVSC_INVALID_INDEX)
 818		rpkt->send_buf_section_size = 0;
 819	else
 820		rpkt->send_buf_section_size = packet->total_data_buflen;
 821
 822	req_id = (ulong)skb;
 823
 824	if (out_channel->rescind)
 825		return -ENODEV;
 826
 827	trace_nvsp_send_pkt(ndev, out_channel, rpkt);
 828
 829	if (packet->page_buf_cnt) {
 830		if (packet->cp_partial)
 831			pb += packet->rmsg_pgcnt;
 832
 833		ret = vmbus_sendpacket_pagebuffer(out_channel,
 834						  pb, packet->page_buf_cnt,
 835						  &nvmsg, sizeof(nvmsg),
 836						  req_id);
 837	} else {
 838		ret = vmbus_sendpacket(out_channel,
 839				       &nvmsg, sizeof(nvmsg),
 840				       req_id, VM_PKT_DATA_INBAND,
 841				       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 842	}
 843
 844	if (ret == 0) {
 845		atomic_inc_return(&nvchan->queue_sends);
 846
 847		if (ring_avail < RING_AVAIL_PERCENT_LOWATER) {
 848			netif_tx_stop_queue(txq);
 849			ndev_ctx->eth_stats.stop_queue++;
 850		}
 851	} else if (ret == -EAGAIN) {
 852		netif_tx_stop_queue(txq);
 853		ndev_ctx->eth_stats.stop_queue++;
 854		if (atomic_read(&nvchan->queue_sends) < 1) {
 855			netif_tx_wake_queue(txq);
 856			ndev_ctx->eth_stats.wake_queue++;
 857			ret = -ENOSPC;
 858		}
 859	} else {
 860		netdev_err(ndev,
 861			   "Unable to send packet pages %u len %u, ret %d\n",
 862			   packet->page_buf_cnt, packet->total_data_buflen,
 863			   ret);
 864	}
 865
 
 
 
 
 
 
 
 
 
 866	return ret;
 867}
 868
 869/* Move packet out of multi send data (msd), and clear msd */
 870static inline void move_pkt_msd(struct hv_netvsc_packet **msd_send,
 871				struct sk_buff **msd_skb,
 872				struct multi_send_data *msdp)
 873{
 874	*msd_skb = msdp->skb;
 875	*msd_send = msdp->pkt;
 876	msdp->skb = NULL;
 877	msdp->pkt = NULL;
 878	msdp->count = 0;
 879}
 880
 881/* RCU already held by caller */
 882int netvsc_send(struct net_device *ndev,
 883		struct hv_netvsc_packet *packet,
 884		struct rndis_message *rndis_msg,
 885		struct hv_page_buffer *pb,
 886		struct sk_buff *skb)
 887{
 888	struct net_device_context *ndev_ctx = netdev_priv(ndev);
 889	struct netvsc_device *net_device
 890		= rcu_dereference_bh(ndev_ctx->nvdev);
 891	struct hv_device *device = ndev_ctx->device_ctx;
 892	int ret = 0;
 893	struct netvsc_channel *nvchan;
 894	u32 pktlen = packet->total_data_buflen, msd_len = 0;
 895	unsigned int section_index = NETVSC_INVALID_INDEX;
 896	struct multi_send_data *msdp;
 897	struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
 898	struct sk_buff *msd_skb = NULL;
 899	bool try_batch, xmit_more;
 900
 901	/* If device is rescinded, return error and packet will get dropped. */
 902	if (unlikely(!net_device || net_device->destroy))
 903		return -ENODEV;
 904
 905	nvchan = &net_device->chan_table[packet->q_idx];
 906	packet->send_buf_index = NETVSC_INVALID_INDEX;
 907	packet->cp_partial = false;
 908
 909	/* Send control message directly without accessing msd (Multi-Send
 910	 * Data) field which may be changed during data packet processing.
 911	 */
 912	if (!skb)
 913		return netvsc_send_pkt(device, packet, net_device, pb, skb);
 914
 915	/* batch packets in send buffer if possible */
 916	msdp = &nvchan->msd;
 917	if (msdp->pkt)
 918		msd_len = msdp->pkt->total_data_buflen;
 919
 920	try_batch =  msd_len > 0 && msdp->count < net_device->max_pkt;
 921	if (try_batch && msd_len + pktlen + net_device->pkt_align <
 922	    net_device->send_section_size) {
 923		section_index = msdp->pkt->send_buf_index;
 924
 925	} else if (try_batch && msd_len + packet->rmsg_size <
 926		   net_device->send_section_size) {
 927		section_index = msdp->pkt->send_buf_index;
 928		packet->cp_partial = true;
 929
 930	} else if (pktlen + net_device->pkt_align <
 931		   net_device->send_section_size) {
 932		section_index = netvsc_get_next_send_section(net_device);
 933		if (unlikely(section_index == NETVSC_INVALID_INDEX)) {
 934			++ndev_ctx->eth_stats.tx_send_full;
 935		} else {
 936			move_pkt_msd(&msd_send, &msd_skb, msdp);
 937			msd_len = 0;
 938		}
 939	}
 940
 941	/* Keep aggregating only if stack says more data is coming
 942	 * and not doing mixed modes send and not flow blocked
 943	 */
 944	xmit_more = skb->xmit_more &&
 945		!packet->cp_partial &&
 946		!netif_xmit_stopped(netdev_get_tx_queue(ndev, packet->q_idx));
 947
 948	if (section_index != NETVSC_INVALID_INDEX) {
 949		netvsc_copy_to_send_buf(net_device,
 950					section_index, msd_len,
 951					packet, rndis_msg, pb, xmit_more);
 952
 953		packet->send_buf_index = section_index;
 954
 955		if (packet->cp_partial) {
 956			packet->page_buf_cnt -= packet->rmsg_pgcnt;
 957			packet->total_data_buflen = msd_len + packet->rmsg_size;
 958		} else {
 959			packet->page_buf_cnt = 0;
 960			packet->total_data_buflen += msd_len;
 961		}
 962
 963		if (msdp->pkt) {
 964			packet->total_packets += msdp->pkt->total_packets;
 965			packet->total_bytes += msdp->pkt->total_bytes;
 966		}
 967
 968		if (msdp->skb)
 969			dev_consume_skb_any(msdp->skb);
 970
 971		if (xmit_more) {
 972			msdp->skb = skb;
 973			msdp->pkt = packet;
 974			msdp->count++;
 975		} else {
 976			cur_send = packet;
 977			msdp->skb = NULL;
 978			msdp->pkt = NULL;
 979			msdp->count = 0;
 980		}
 981	} else {
 982		move_pkt_msd(&msd_send, &msd_skb, msdp);
 983		cur_send = packet;
 984	}
 985
 986	if (msd_send) {
 987		int m_ret = netvsc_send_pkt(device, msd_send, net_device,
 988					    NULL, msd_skb);
 989
 990		if (m_ret != 0) {
 991			netvsc_free_send_slot(net_device,
 992					      msd_send->send_buf_index);
 993			dev_kfree_skb_any(msd_skb);
 994		}
 995	}
 996
 997	if (cur_send)
 998		ret = netvsc_send_pkt(device, cur_send, net_device, pb, skb);
 999
1000	if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
1001		netvsc_free_send_slot(net_device, section_index);
1002
1003	return ret;
1004}
1005
1006/* Send pending recv completions */
1007static int send_recv_completions(struct net_device *ndev,
1008				 struct netvsc_device *nvdev,
1009				 struct netvsc_channel *nvchan)
1010{
1011	struct multi_recv_comp *mrc = &nvchan->mrc;
1012	struct recv_comp_msg {
1013		struct nvsp_message_header hdr;
1014		u32 status;
1015	}  __packed;
1016	struct recv_comp_msg msg = {
1017		.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE,
1018	};
1019	int ret;
1020
1021	while (mrc->first != mrc->next) {
1022		const struct recv_comp_data *rcd
1023			= mrc->slots + mrc->first;
1024
1025		msg.status = rcd->status;
1026		ret = vmbus_sendpacket(nvchan->channel, &msg, sizeof(msg),
1027				       rcd->tid, VM_PKT_COMP, 0);
1028		if (unlikely(ret)) {
1029			struct net_device_context *ndev_ctx = netdev_priv(ndev);
1030
1031			++ndev_ctx->eth_stats.rx_comp_busy;
1032			return ret;
1033		}
1034
1035		if (++mrc->first == nvdev->recv_completion_cnt)
1036			mrc->first = 0;
1037	}
1038
1039	/* receive completion ring has been emptied */
1040	if (unlikely(nvdev->destroy))
1041		wake_up(&nvdev->wait_drain);
1042
1043	return 0;
1044}
1045
1046/* Count how many receive completions are outstanding */
1047static void recv_comp_slot_avail(const struct netvsc_device *nvdev,
1048				 const struct multi_recv_comp *mrc,
1049				 u32 *filled, u32 *avail)
1050{
1051	u32 count = nvdev->recv_completion_cnt;
1052
1053	if (mrc->next >= mrc->first)
1054		*filled = mrc->next - mrc->first;
1055	else
1056		*filled = (count - mrc->first) + mrc->next;
1057
1058	*avail = count - *filled - 1;
1059}
1060
1061/* Add receive complete to ring to send to host. */
1062static void enq_receive_complete(struct net_device *ndev,
1063				 struct netvsc_device *nvdev, u16 q_idx,
1064				 u64 tid, u32 status)
1065{
1066	struct netvsc_channel *nvchan = &nvdev->chan_table[q_idx];
1067	struct multi_recv_comp *mrc = &nvchan->mrc;
1068	struct recv_comp_data *rcd;
1069	u32 filled, avail;
1070
1071	recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1072
1073	if (unlikely(filled > NAPI_POLL_WEIGHT)) {
1074		send_recv_completions(ndev, nvdev, nvchan);
1075		recv_comp_slot_avail(nvdev, mrc, &filled, &avail);
1076	}
1077
1078	if (unlikely(!avail)) {
1079		netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
1080			   q_idx, tid);
1081		return;
1082	}
1083
1084	rcd = mrc->slots + mrc->next;
1085	rcd->tid = tid;
1086	rcd->status = status;
1087
1088	if (++mrc->next == nvdev->recv_completion_cnt)
1089		mrc->next = 0;
1090}
1091
1092static int netvsc_receive(struct net_device *ndev,
1093			  struct netvsc_device *net_device,
1094			  struct net_device_context *net_device_ctx,
1095			  struct hv_device *device,
1096			  struct vmbus_channel *channel,
1097			  const struct vmpacket_descriptor *desc,
1098			  struct nvsp_message *nvsp)
1099{
 
 
1100	const struct vmtransfer_page_packet_header *vmxferpage_packet
1101		= container_of(desc, const struct vmtransfer_page_packet_header, d);
1102	u16 q_idx = channel->offermsg.offer.sub_channel_index;
1103	char *recv_buf = net_device->recv_buf;
1104	u32 status = NVSP_STAT_SUCCESS;
1105	int i;
1106	int count = 0;
1107
1108	/* Make sure this is a valid nvsp packet */
1109	if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {
1110		netif_err(net_device_ctx, rx_err, ndev,
1111			  "Unknown nvsp packet type received %u\n",
1112			  nvsp->hdr.msg_type);
1113		return 0;
1114	}
1115
1116	if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
1117		netif_err(net_device_ctx, rx_err, ndev,
1118			  "Invalid xfer page set id - expecting %x got %x\n",
1119			  NETVSC_RECEIVE_BUFFER_ID,
1120			  vmxferpage_packet->xfer_pageset_id);
1121		return 0;
1122	}
1123
1124	count = vmxferpage_packet->range_cnt;
1125
1126	/* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1127	for (i = 0; i < count; i++) {
1128		u32 offset = vmxferpage_packet->ranges[i].byte_offset;
1129		u32 buflen = vmxferpage_packet->ranges[i].byte_count;
1130		void *data;
1131		int ret;
1132
1133		if (unlikely(offset + buflen > net_device->recv_buf_size)) {
 
1134			status = NVSP_STAT_FAIL;
1135			netif_err(net_device_ctx, rx_err, ndev,
1136				  "Packet offset:%u + len:%u too big\n",
1137				  offset, buflen);
1138
1139			continue;
1140		}
1141
1142		data = recv_buf + offset;
1143
 
 
1144		trace_rndis_recv(ndev, q_idx, data);
1145
1146		/* Pass it to the upper layer */
1147		ret = rndis_filter_receive(ndev, net_device,
1148					   channel, data, buflen);
1149
1150		if (unlikely(ret != NVSP_STAT_SUCCESS))
1151			status = NVSP_STAT_FAIL;
1152	}
1153
1154	enq_receive_complete(ndev, net_device, q_idx,
1155			     vmxferpage_packet->d.trans_id, status);
1156
1157	return count;
1158}
1159
1160static void netvsc_send_table(struct hv_device *hdev,
1161			      struct nvsp_message *nvmsg)
 
 
1162{
1163	struct net_device *ndev = hv_get_drvdata(hdev);
1164	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 
1165	int i;
1166	u32 count, *tab;
1167
1168	count = nvmsg->msg.v5_msg.send_table.count;
 
 
1169	if (count != VRSS_SEND_TAB_SIZE) {
1170		netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1171		return;
1172	}
1173
1174	tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1175		      nvmsg->msg.v5_msg.send_table.offset);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1176
1177	for (i = 0; i < count; i++)
1178		net_device_ctx->tx_table[i] = tab[i];
1179}
1180
1181static void netvsc_send_vf(struct net_device_context *net_device_ctx,
1182			   struct nvsp_message *nvmsg)
1183{
 
 
1184	net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1185	net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
 
 
 
1186}
1187
1188static inline void netvsc_receive_inband(struct hv_device *hdev,
1189				 struct net_device_context *net_device_ctx,
1190				 struct nvsp_message *nvmsg)
 
1191{
1192	switch (nvmsg->hdr.msg_type) {
1193	case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1194		netvsc_send_table(hdev, nvmsg);
1195		break;
1196
1197	case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1198		netvsc_send_vf(net_device_ctx, nvmsg);
1199		break;
1200	}
1201}
1202
1203static int netvsc_process_raw_pkt(struct hv_device *device,
1204				  struct vmbus_channel *channel,
1205				  struct netvsc_device *net_device,
1206				  struct net_device *ndev,
1207				  const struct vmpacket_descriptor *desc,
1208				  int budget)
1209{
1210	struct net_device_context *net_device_ctx = netdev_priv(ndev);
1211	struct nvsp_message *nvmsg = hv_pkt_data(desc);
 
1212
1213	trace_nvsp_recv(ndev, channel, nvmsg);
1214
1215	switch (desc->type) {
1216	case VM_PKT_COMP:
1217		netvsc_send_completion(net_device, channel, device,
1218				       desc, budget);
1219		break;
1220
1221	case VM_PKT_DATA_USING_XFER_PAGES:
1222		return netvsc_receive(ndev, net_device, net_device_ctx,
1223				      device, channel, desc, nvmsg);
1224		break;
1225
1226	case VM_PKT_DATA_INBAND:
1227		netvsc_receive_inband(device, net_device_ctx, nvmsg);
1228		break;
1229
1230	default:
1231		netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1232			   desc->type, desc->trans_id);
1233		break;
1234	}
1235
1236	return 0;
1237}
1238
1239static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
1240{
1241	struct vmbus_channel *primary = channel->primary_channel;
1242
1243	return primary ? primary->device_obj : channel->device_obj;
1244}
1245
1246/* Network processing softirq
1247 * Process data in incoming ring buffer from host
1248 * Stops when ring is empty or budget is met or exceeded.
1249 */
1250int netvsc_poll(struct napi_struct *napi, int budget)
1251{
1252	struct netvsc_channel *nvchan
1253		= container_of(napi, struct netvsc_channel, napi);
1254	struct netvsc_device *net_device = nvchan->net_device;
1255	struct vmbus_channel *channel = nvchan->channel;
1256	struct hv_device *device = netvsc_channel_to_device(channel);
1257	struct net_device *ndev = hv_get_drvdata(device);
1258	int work_done = 0;
 
1259
1260	/* If starting a new interval */
1261	if (!nvchan->desc)
1262		nvchan->desc = hv_pkt_iter_first(channel);
1263
1264	while (nvchan->desc && work_done < budget) {
1265		work_done += netvsc_process_raw_pkt(device, channel, net_device,
1266						    ndev, nvchan->desc, budget);
1267		nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
1268	}
1269
1270	/* If send of pending receive completions suceeded
1271	 *   and did not exhaust NAPI budget this time
1272	 *   and not doing busy poll
 
 
1273	 * then re-enable host interrupts
1274	 *     and reschedule if ring is not empty.
 
1275	 */
1276	if (send_recv_completions(ndev, net_device, nvchan) == 0 &&
1277	    work_done < budget &&
1278	    napi_complete_done(napi, work_done) &&
1279	    hv_end_read(&channel->inbound) &&
1280	    napi_schedule_prep(napi)) {
1281		hv_begin_read(&channel->inbound);
1282		__napi_schedule(napi);
1283	}
1284
1285	/* Driver may overshoot since multiple packets per descriptor */
1286	return min(work_done, budget);
1287}
1288
1289/* Call back when data is available in host ring buffer.
1290 * Processing is deferred until network softirq (NAPI)
1291 */
1292void netvsc_channel_cb(void *context)
1293{
1294	struct netvsc_channel *nvchan = context;
1295	struct vmbus_channel *channel = nvchan->channel;
1296	struct hv_ring_buffer_info *rbi = &channel->inbound;
1297
1298	/* preload first vmpacket descriptor */
1299	prefetch(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
1300
1301	if (napi_schedule_prep(&nvchan->napi)) {
1302		/* disable interupts from host */
1303		hv_begin_read(rbi);
1304
1305		__napi_schedule_irqoff(&nvchan->napi);
1306	}
1307}
1308
1309/*
1310 * netvsc_device_add - Callback when the device belonging to this
1311 * driver is added
1312 */
1313struct netvsc_device *netvsc_device_add(struct hv_device *device,
1314				const struct netvsc_device_info *device_info)
1315{
1316	int i, ret = 0;
1317	struct netvsc_device *net_device;
1318	struct net_device *ndev = hv_get_drvdata(device);
1319	struct net_device_context *net_device_ctx = netdev_priv(ndev);
1320
1321	net_device = alloc_net_device();
1322	if (!net_device)
1323		return ERR_PTR(-ENOMEM);
1324
1325	for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
1326		net_device_ctx->tx_table[i] = 0;
1327
1328	/* Because the device uses NAPI, all the interrupt batching and
1329	 * control is done via Net softirq, not the channel handling
1330	 */
1331	set_channel_read_mode(device->channel, HV_CALL_ISR);
1332
1333	/* If we're reopening the device we may have multiple queues, fill the
1334	 * chn_table with the default channel to use it before subchannels are
1335	 * opened.
1336	 * Initialize the channel state before we open;
1337	 * we can be interrupted as soon as we open the channel.
1338	 */
1339
1340	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
1341		struct netvsc_channel *nvchan = &net_device->chan_table[i];
1342
1343		nvchan->channel = device->channel;
1344		nvchan->net_device = net_device;
1345		u64_stats_init(&nvchan->tx_stats.syncp);
1346		u64_stats_init(&nvchan->rx_stats.syncp);
1347	}
1348
1349	/* Enable NAPI handler before init callbacks */
1350	netif_napi_add(ndev, &net_device->chan_table[0].napi,
1351		       netvsc_poll, NAPI_POLL_WEIGHT);
1352
1353	/* Open the channel */
1354	ret = vmbus_open(device->channel, netvsc_ring_bytes,
1355			 netvsc_ring_bytes,  NULL, 0,
1356			 netvsc_channel_cb, net_device->chan_table);
1357
1358	if (ret != 0) {
1359		netdev_err(ndev, "unable to open channel: %d\n", ret);
1360		goto cleanup;
1361	}
1362
1363	/* Channel is opened */
1364	netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
1365
1366	napi_enable(&net_device->chan_table[0].napi);
1367
1368	/* Connect with the NetVsp */
1369	ret = netvsc_connect_vsp(device, net_device, device_info);
1370	if (ret != 0) {
1371		netdev_err(ndev,
1372			"unable to connect to NetVSP - %d\n", ret);
1373		goto close;
1374	}
1375
1376	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1377	 * populated.
1378	 */
1379	rcu_assign_pointer(net_device_ctx->nvdev, net_device);
1380
1381	return net_device;
1382
1383close:
1384	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
1385	napi_disable(&net_device->chan_table[0].napi);
1386
1387	/* Now, we can close the channel safely */
1388	vmbus_close(device->channel);
1389
1390cleanup:
1391	netif_napi_del(&net_device->chan_table[0].napi);
1392	free_netvsc_device(&net_device->rcu);
1393
1394	return ERR_PTR(ret);
1395}
v5.4
   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 */
  33void 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 */
  61static 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
  92static 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
 114static 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
 131static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
 132{
 133	call_rcu(&nvdev->rcu, free_netvsc_device);
 134}
 135
 136static 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
 186static 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
 237static 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
 259static 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
 281int 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
 295static 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
 478cleanup:
 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
 484exit:
 485	return ret;
 486}
 487
 488/* Negotiate NVSP protocol version */
 489static 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
 548static 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
 607cleanup:
 608	return ret;
 609}
 610
 611/*
 612 * netvsc_device_remove - Callback when the root bus device is removed
 613 */
 614void 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
 
 
 
 
 
 
 
 
 
 
 
 665static 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
 671static 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
 721static 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
 752static 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
 765static 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
 803static 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 */
 887static 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 */
 899int 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 */
1024static 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 */
1064static 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. */
1079static 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
1109static 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
1180static void netvsc_send_table(struct net_device *ndev,
1181			      struct netvsc_device *nvscdev,
1182			      const struct nvsp_message *nvmsg,
1183			      u32 msglen)
1184{
 
1185	struct net_device_context *net_device_ctx = netdev_priv(ndev);
1186	u32 count, offset, *tab;
1187	int i;
 
1188
1189	count = nvmsg->msg.v5_msg.send_table.count;
1190	offset = nvmsg->msg.v5_msg.send_table.offset;
1191
1192	if (count != VRSS_SEND_TAB_SIZE) {
1193		netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1194		return;
1195	}
1196
1197	/* If negotiated version <= NVSP_PROTOCOL_VERSION_6, the offset may be
1198	 * wrong due to a host bug. So fix the offset here.
1199	 */
1200	if (nvscdev->nvsp_version <= NVSP_PROTOCOL_VERSION_6 &&
1201	    msglen >= sizeof(struct nvsp_message_header) +
1202	    sizeof(union nvsp_6_message_uber) + count * sizeof(u32))
1203		offset = sizeof(struct nvsp_message_header) +
1204			 sizeof(union nvsp_6_message_uber);
1205
1206	/* Boundary check for all versions */
1207	if (offset > msglen - count * sizeof(u32)) {
1208		netdev_err(ndev, "Received send-table offset too big:%u\n",
1209			   offset);
1210		return;
1211	}
1212
1213	tab = (void *)nvmsg + offset;
1214
1215	for (i = 0; i < count; i++)
1216		net_device_ctx->tx_table[i] = tab[i];
1217}
1218
1219static void netvsc_send_vf(struct net_device *ndev,
1220			   const struct nvsp_message *nvmsg)
1221{
1222	struct net_device_context *net_device_ctx = netdev_priv(ndev);
1223
1224	net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
1225	net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
1226	netdev_info(ndev, "VF slot %u %s\n",
1227		    net_device_ctx->vf_serial,
1228		    net_device_ctx->vf_alloc ? "added" : "removed");
1229}
1230
1231static void netvsc_receive_inband(struct net_device *ndev,
1232				  struct netvsc_device *nvscdev,
1233				  const struct nvsp_message *nvmsg,
1234				  u32 msglen)
1235{
1236	switch (nvmsg->hdr.msg_type) {
1237	case NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE:
1238		netvsc_send_table(ndev, nvscdev, nvmsg, msglen);
1239		break;
1240
1241	case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
1242		netvsc_send_vf(ndev, nvmsg);
1243		break;
1244	}
1245}
1246
1247static int netvsc_process_raw_pkt(struct hv_device *device,
1248				  struct netvsc_channel *nvchan,
1249				  struct netvsc_device *net_device,
1250				  struct net_device *ndev,
1251				  const struct vmpacket_descriptor *desc,
1252				  int budget)
1253{
1254	struct vmbus_channel *channel = nvchan->channel;
1255	const struct nvsp_message *nvmsg = hv_pkt_data(desc);
1256	u32 msglen = hv_pkt_datalen(desc);
1257
1258	trace_nvsp_recv(ndev, channel, nvmsg);
1259
1260	switch (desc->type) {
1261	case VM_PKT_COMP:
1262		netvsc_send_completion(ndev, net_device, channel,
1263				       desc, budget);
1264		break;
1265
1266	case VM_PKT_DATA_USING_XFER_PAGES:
1267		return netvsc_receive(ndev, net_device, nvchan,
1268				      desc, nvmsg);
1269		break;
1270
1271	case VM_PKT_DATA_INBAND:
1272		netvsc_receive_inband(ndev, net_device, nvmsg, msglen);
1273		break;
1274
1275	default:
1276		netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
1277			   desc->type, desc->trans_id);
1278		break;
1279	}
1280
1281	return 0;
1282}
1283
1284static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
1285{
1286	struct vmbus_channel *primary = channel->primary_channel;
1287
1288	return primary ? primary->device_obj : channel->device_obj;
1289}
1290
1291/* Network processing softirq
1292 * Process data in incoming ring buffer from host
1293 * Stops when ring is empty or budget is met or exceeded.
1294 */
1295int netvsc_poll(struct napi_struct *napi, int budget)
1296{
1297	struct netvsc_channel *nvchan
1298		= container_of(napi, struct netvsc_channel, napi);
1299	struct netvsc_device *net_device = nvchan->net_device;
1300	struct vmbus_channel *channel = nvchan->channel;
1301	struct hv_device *device = netvsc_channel_to_device(channel);
1302	struct net_device *ndev = hv_get_drvdata(device);
1303	int work_done = 0;
1304	int ret;
1305
1306	/* If starting a new interval */
1307	if (!nvchan->desc)
1308		nvchan->desc = hv_pkt_iter_first(channel);
1309
1310	while (nvchan->desc && work_done < budget) {
1311		work_done += netvsc_process_raw_pkt(device, nvchan, net_device,
1312						    ndev, nvchan->desc, budget);
1313		nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
1314	}
1315
1316	/* Send any pending receive completions */
1317	ret = send_recv_completions(ndev, net_device, nvchan);
1318
1319	/* If it did not exhaust NAPI budget this time
1320	 *  and not doing busy poll
1321	 * then re-enable host interrupts
1322	 *  and reschedule if ring is not empty
1323	 *   or sending receive completion failed.
1324	 */
1325	if (work_done < budget &&
 
1326	    napi_complete_done(napi, work_done) &&
1327	    (ret || hv_end_read(&channel->inbound)) &&
1328	    napi_schedule_prep(napi)) {
1329		hv_begin_read(&channel->inbound);
1330		__napi_schedule(napi);
1331	}
1332
1333	/* Driver may overshoot since multiple packets per descriptor */
1334	return min(work_done, budget);
1335}
1336
1337/* Call back when data is available in host ring buffer.
1338 * Processing is deferred until network softirq (NAPI)
1339 */
1340void netvsc_channel_cb(void *context)
1341{
1342	struct netvsc_channel *nvchan = context;
1343	struct vmbus_channel *channel = nvchan->channel;
1344	struct hv_ring_buffer_info *rbi = &channel->inbound;
1345
1346	/* preload first vmpacket descriptor */
1347	prefetch(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
1348
1349	if (napi_schedule_prep(&nvchan->napi)) {
1350		/* disable interrupts from host */
1351		hv_begin_read(rbi);
1352
1353		__napi_schedule_irqoff(&nvchan->napi);
1354	}
1355}
1356
1357/*
1358 * netvsc_device_add - Callback when the device belonging to this
1359 * driver is added
1360 */
1361struct netvsc_device *netvsc_device_add(struct hv_device *device,
1362				const struct netvsc_device_info *device_info)
1363{
1364	int i, ret = 0;
1365	struct netvsc_device *net_device;
1366	struct net_device *ndev = hv_get_drvdata(device);
1367	struct net_device_context *net_device_ctx = netdev_priv(ndev);
1368
1369	net_device = alloc_net_device();
1370	if (!net_device)
1371		return ERR_PTR(-ENOMEM);
1372
1373	for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
1374		net_device_ctx->tx_table[i] = 0;
1375
1376	/* Because the device uses NAPI, all the interrupt batching and
1377	 * control is done via Net softirq, not the channel handling
1378	 */
1379	set_channel_read_mode(device->channel, HV_CALL_ISR);
1380
1381	/* If we're reopening the device we may have multiple queues, fill the
1382	 * chn_table with the default channel to use it before subchannels are
1383	 * opened.
1384	 * Initialize the channel state before we open;
1385	 * we can be interrupted as soon as we open the channel.
1386	 */
1387
1388	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
1389		struct netvsc_channel *nvchan = &net_device->chan_table[i];
1390
1391		nvchan->channel = device->channel;
1392		nvchan->net_device = net_device;
1393		u64_stats_init(&nvchan->tx_stats.syncp);
1394		u64_stats_init(&nvchan->rx_stats.syncp);
1395	}
1396
1397	/* Enable NAPI handler before init callbacks */
1398	netif_napi_add(ndev, &net_device->chan_table[0].napi,
1399		       netvsc_poll, NAPI_POLL_WEIGHT);
1400
1401	/* Open the channel */
1402	ret = vmbus_open(device->channel, netvsc_ring_bytes,
1403			 netvsc_ring_bytes,  NULL, 0,
1404			 netvsc_channel_cb, net_device->chan_table);
1405
1406	if (ret != 0) {
1407		netdev_err(ndev, "unable to open channel: %d\n", ret);
1408		goto cleanup;
1409	}
1410
1411	/* Channel is opened */
1412	netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
1413
1414	napi_enable(&net_device->chan_table[0].napi);
1415
1416	/* Connect with the NetVsp */
1417	ret = netvsc_connect_vsp(device, net_device, device_info);
1418	if (ret != 0) {
1419		netdev_err(ndev,
1420			"unable to connect to NetVSP - %d\n", ret);
1421		goto close;
1422	}
1423
1424	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
1425	 * populated.
1426	 */
1427	rcu_assign_pointer(net_device_ctx->nvdev, net_device);
1428
1429	return net_device;
1430
1431close:
1432	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
1433	napi_disable(&net_device->chan_table[0].napi);
1434
1435	/* Now, we can close the channel safely */
1436	vmbus_close(device->channel);
1437
1438cleanup:
1439	netif_napi_del(&net_device->chan_table[0].napi);
1440	free_netvsc_device(&net_device->rcu);
1441
1442	return ERR_PTR(ret);
1443}