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 *   K. Y. Srinivasan <kys@microsoft.com>
   9 */
  10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12#include <linux/init.h>
  13#include <linux/module.h>
  14#include <linux/device.h>
  15#include <linux/interrupt.h>
  16#include <linux/sysctl.h>
  17#include <linux/slab.h>
  18#include <linux/acpi.h>
  19#include <linux/completion.h>
  20#include <linux/hyperv.h>
  21#include <linux/kernel_stat.h>
  22#include <linux/clockchips.h>
  23#include <linux/cpu.h>
  24#include <linux/sched/task_stack.h>
  25
  26#include <asm/mshyperv.h>
  27#include <linux/delay.h>
  28#include <linux/notifier.h>
  29#include <linux/ptrace.h>
  30#include <linux/screen_info.h>
  31#include <linux/kdebug.h>
  32#include <linux/efi.h>
  33#include <linux/random.h>
 
  34#include <linux/syscore_ops.h>
  35#include <clocksource/hyperv_timer.h>
  36#include "hyperv_vmbus.h"
  37
  38struct vmbus_dynid {
  39	struct list_head node;
  40	struct hv_vmbus_device_id id;
  41};
  42
  43static struct acpi_device  *hv_acpi_dev;
  44
  45static struct completion probe_event;
  46
  47static int hyperv_cpuhp_online;
  48
  49static void *hv_panic_page;
  50
 
 
 
 
 
 
 
 
 
 
 
 
  51static int hyperv_panic_event(struct notifier_block *nb, unsigned long val,
  52			      void *args)
  53{
  54	struct pt_regs *regs;
  55
  56	regs = current_pt_regs();
  57
  58	hyperv_report_panic(regs, val);
 
 
 
 
 
 
 
 
 
  59	return NOTIFY_DONE;
  60}
  61
  62static int hyperv_die_event(struct notifier_block *nb, unsigned long val,
  63			    void *args)
  64{
  65	struct die_args *die = (struct die_args *)args;
  66	struct pt_regs *regs = die->regs;
  67
  68	hyperv_report_panic(regs, val);
 
 
 
 
 
 
 
 
 
 
  69	return NOTIFY_DONE;
  70}
  71
  72static struct notifier_block hyperv_die_block = {
  73	.notifier_call = hyperv_die_event,
  74};
  75static struct notifier_block hyperv_panic_block = {
  76	.notifier_call = hyperv_panic_event,
  77};
  78
  79static const char *fb_mmio_name = "fb_range";
  80static struct resource *fb_mmio;
  81static struct resource *hyperv_mmio;
  82static DEFINE_SEMAPHORE(hyperv_mmio_lock);
  83
  84static int vmbus_exists(void)
  85{
  86	if (hv_acpi_dev == NULL)
  87		return -ENODEV;
  88
  89	return 0;
  90}
  91
  92#define VMBUS_ALIAS_LEN ((sizeof((struct hv_vmbus_device_id *)0)->guid) * 2)
  93static void print_alias_name(struct hv_device *hv_dev, char *alias_name)
  94{
  95	int i;
  96	for (i = 0; i < VMBUS_ALIAS_LEN; i += 2)
  97		sprintf(&alias_name[i], "%02x", hv_dev->dev_type.b[i/2]);
  98}
  99
 100static u8 channel_monitor_group(const struct vmbus_channel *channel)
 101{
 102	return (u8)channel->offermsg.monitorid / 32;
 103}
 104
 105static u8 channel_monitor_offset(const struct vmbus_channel *channel)
 106{
 107	return (u8)channel->offermsg.monitorid % 32;
 108}
 109
 110static u32 channel_pending(const struct vmbus_channel *channel,
 111			   const struct hv_monitor_page *monitor_page)
 112{
 113	u8 monitor_group = channel_monitor_group(channel);
 114
 115	return monitor_page->trigger_group[monitor_group].pending;
 116}
 117
 118static u32 channel_latency(const struct vmbus_channel *channel,
 119			   const struct hv_monitor_page *monitor_page)
 120{
 121	u8 monitor_group = channel_monitor_group(channel);
 122	u8 monitor_offset = channel_monitor_offset(channel);
 123
 124	return monitor_page->latency[monitor_group][monitor_offset];
 125}
 126
 127static u32 channel_conn_id(struct vmbus_channel *channel,
 128			   struct hv_monitor_page *monitor_page)
 129{
 130	u8 monitor_group = channel_monitor_group(channel);
 131	u8 monitor_offset = channel_monitor_offset(channel);
 132	return monitor_page->parameter[monitor_group][monitor_offset].connectionid.u.id;
 133}
 134
 135static ssize_t id_show(struct device *dev, struct device_attribute *dev_attr,
 136		       char *buf)
 137{
 138	struct hv_device *hv_dev = device_to_hv_device(dev);
 139
 140	if (!hv_dev->channel)
 141		return -ENODEV;
 142	return sprintf(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
 143}
 144static DEVICE_ATTR_RO(id);
 145
 146static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,
 147			  char *buf)
 148{
 149	struct hv_device *hv_dev = device_to_hv_device(dev);
 150
 151	if (!hv_dev->channel)
 152		return -ENODEV;
 153	return sprintf(buf, "%d\n", hv_dev->channel->state);
 154}
 155static DEVICE_ATTR_RO(state);
 156
 157static ssize_t monitor_id_show(struct device *dev,
 158			       struct device_attribute *dev_attr, char *buf)
 159{
 160	struct hv_device *hv_dev = device_to_hv_device(dev);
 161
 162	if (!hv_dev->channel)
 163		return -ENODEV;
 164	return sprintf(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
 165}
 166static DEVICE_ATTR_RO(monitor_id);
 167
 168static ssize_t class_id_show(struct device *dev,
 169			       struct device_attribute *dev_attr, char *buf)
 170{
 171	struct hv_device *hv_dev = device_to_hv_device(dev);
 172
 173	if (!hv_dev->channel)
 174		return -ENODEV;
 175	return sprintf(buf, "{%pUl}\n",
 176		       hv_dev->channel->offermsg.offer.if_type.b);
 177}
 178static DEVICE_ATTR_RO(class_id);
 179
 180static ssize_t device_id_show(struct device *dev,
 181			      struct device_attribute *dev_attr, char *buf)
 182{
 183	struct hv_device *hv_dev = device_to_hv_device(dev);
 184
 185	if (!hv_dev->channel)
 186		return -ENODEV;
 187	return sprintf(buf, "{%pUl}\n",
 188		       hv_dev->channel->offermsg.offer.if_instance.b);
 189}
 190static DEVICE_ATTR_RO(device_id);
 191
 192static ssize_t modalias_show(struct device *dev,
 193			     struct device_attribute *dev_attr, char *buf)
 194{
 195	struct hv_device *hv_dev = device_to_hv_device(dev);
 196	char alias_name[VMBUS_ALIAS_LEN + 1];
 197
 198	print_alias_name(hv_dev, alias_name);
 199	return sprintf(buf, "vmbus:%s\n", alias_name);
 200}
 201static DEVICE_ATTR_RO(modalias);
 202
 203#ifdef CONFIG_NUMA
 204static ssize_t numa_node_show(struct device *dev,
 205			      struct device_attribute *attr, char *buf)
 206{
 207	struct hv_device *hv_dev = device_to_hv_device(dev);
 208
 209	if (!hv_dev->channel)
 210		return -ENODEV;
 211
 212	return sprintf(buf, "%d\n", hv_dev->channel->numa_node);
 213}
 214static DEVICE_ATTR_RO(numa_node);
 215#endif
 216
 217static ssize_t server_monitor_pending_show(struct device *dev,
 218					   struct device_attribute *dev_attr,
 219					   char *buf)
 220{
 221	struct hv_device *hv_dev = device_to_hv_device(dev);
 222
 223	if (!hv_dev->channel)
 224		return -ENODEV;
 225	return sprintf(buf, "%d\n",
 226		       channel_pending(hv_dev->channel,
 227				       vmbus_connection.monitor_pages[0]));
 228}
 229static DEVICE_ATTR_RO(server_monitor_pending);
 230
 231static ssize_t client_monitor_pending_show(struct device *dev,
 232					   struct device_attribute *dev_attr,
 233					   char *buf)
 234{
 235	struct hv_device *hv_dev = device_to_hv_device(dev);
 236
 237	if (!hv_dev->channel)
 238		return -ENODEV;
 239	return sprintf(buf, "%d\n",
 240		       channel_pending(hv_dev->channel,
 241				       vmbus_connection.monitor_pages[1]));
 242}
 243static DEVICE_ATTR_RO(client_monitor_pending);
 244
 245static ssize_t server_monitor_latency_show(struct device *dev,
 246					   struct device_attribute *dev_attr,
 247					   char *buf)
 248{
 249	struct hv_device *hv_dev = device_to_hv_device(dev);
 250
 251	if (!hv_dev->channel)
 252		return -ENODEV;
 253	return sprintf(buf, "%d\n",
 254		       channel_latency(hv_dev->channel,
 255				       vmbus_connection.monitor_pages[0]));
 256}
 257static DEVICE_ATTR_RO(server_monitor_latency);
 258
 259static ssize_t client_monitor_latency_show(struct device *dev,
 260					   struct device_attribute *dev_attr,
 261					   char *buf)
 262{
 263	struct hv_device *hv_dev = device_to_hv_device(dev);
 264
 265	if (!hv_dev->channel)
 266		return -ENODEV;
 267	return sprintf(buf, "%d\n",
 268		       channel_latency(hv_dev->channel,
 269				       vmbus_connection.monitor_pages[1]));
 270}
 271static DEVICE_ATTR_RO(client_monitor_latency);
 272
 273static ssize_t server_monitor_conn_id_show(struct device *dev,
 274					   struct device_attribute *dev_attr,
 275					   char *buf)
 276{
 277	struct hv_device *hv_dev = device_to_hv_device(dev);
 278
 279	if (!hv_dev->channel)
 280		return -ENODEV;
 281	return sprintf(buf, "%d\n",
 282		       channel_conn_id(hv_dev->channel,
 283				       vmbus_connection.monitor_pages[0]));
 284}
 285static DEVICE_ATTR_RO(server_monitor_conn_id);
 286
 287static ssize_t client_monitor_conn_id_show(struct device *dev,
 288					   struct device_attribute *dev_attr,
 289					   char *buf)
 290{
 291	struct hv_device *hv_dev = device_to_hv_device(dev);
 292
 293	if (!hv_dev->channel)
 294		return -ENODEV;
 295	return sprintf(buf, "%d\n",
 296		       channel_conn_id(hv_dev->channel,
 297				       vmbus_connection.monitor_pages[1]));
 298}
 299static DEVICE_ATTR_RO(client_monitor_conn_id);
 300
 301static ssize_t out_intr_mask_show(struct device *dev,
 302				  struct device_attribute *dev_attr, char *buf)
 303{
 304	struct hv_device *hv_dev = device_to_hv_device(dev);
 305	struct hv_ring_buffer_debug_info outbound;
 306	int ret;
 307
 308	if (!hv_dev->channel)
 309		return -ENODEV;
 310
 311	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound,
 312					  &outbound);
 313	if (ret < 0)
 314		return ret;
 315
 316	return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
 317}
 318static DEVICE_ATTR_RO(out_intr_mask);
 319
 320static ssize_t out_read_index_show(struct device *dev,
 321				   struct device_attribute *dev_attr, char *buf)
 322{
 323	struct hv_device *hv_dev = device_to_hv_device(dev);
 324	struct hv_ring_buffer_debug_info outbound;
 325	int ret;
 326
 327	if (!hv_dev->channel)
 328		return -ENODEV;
 329
 330	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound,
 331					  &outbound);
 332	if (ret < 0)
 333		return ret;
 334	return sprintf(buf, "%d\n", outbound.current_read_index);
 335}
 336static DEVICE_ATTR_RO(out_read_index);
 337
 338static ssize_t out_write_index_show(struct device *dev,
 339				    struct device_attribute *dev_attr,
 340				    char *buf)
 341{
 342	struct hv_device *hv_dev = device_to_hv_device(dev);
 343	struct hv_ring_buffer_debug_info outbound;
 344	int ret;
 345
 346	if (!hv_dev->channel)
 347		return -ENODEV;
 348
 349	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound,
 350					  &outbound);
 351	if (ret < 0)
 352		return ret;
 353	return sprintf(buf, "%d\n", outbound.current_write_index);
 354}
 355static DEVICE_ATTR_RO(out_write_index);
 356
 357static ssize_t out_read_bytes_avail_show(struct device *dev,
 358					 struct device_attribute *dev_attr,
 359					 char *buf)
 360{
 361	struct hv_device *hv_dev = device_to_hv_device(dev);
 362	struct hv_ring_buffer_debug_info outbound;
 363	int ret;
 364
 365	if (!hv_dev->channel)
 366		return -ENODEV;
 367
 368	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound,
 369					  &outbound);
 370	if (ret < 0)
 371		return ret;
 372	return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
 373}
 374static DEVICE_ATTR_RO(out_read_bytes_avail);
 375
 376static ssize_t out_write_bytes_avail_show(struct device *dev,
 377					  struct device_attribute *dev_attr,
 378					  char *buf)
 379{
 380	struct hv_device *hv_dev = device_to_hv_device(dev);
 381	struct hv_ring_buffer_debug_info outbound;
 382	int ret;
 383
 384	if (!hv_dev->channel)
 385		return -ENODEV;
 386
 387	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound,
 388					  &outbound);
 389	if (ret < 0)
 390		return ret;
 391	return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
 392}
 393static DEVICE_ATTR_RO(out_write_bytes_avail);
 394
 395static ssize_t in_intr_mask_show(struct device *dev,
 396				 struct device_attribute *dev_attr, char *buf)
 397{
 398	struct hv_device *hv_dev = device_to_hv_device(dev);
 399	struct hv_ring_buffer_debug_info inbound;
 400	int ret;
 401
 402	if (!hv_dev->channel)
 403		return -ENODEV;
 404
 405	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
 406	if (ret < 0)
 407		return ret;
 408
 409	return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
 410}
 411static DEVICE_ATTR_RO(in_intr_mask);
 412
 413static ssize_t in_read_index_show(struct device *dev,
 414				  struct device_attribute *dev_attr, char *buf)
 415{
 416	struct hv_device *hv_dev = device_to_hv_device(dev);
 417	struct hv_ring_buffer_debug_info inbound;
 418	int ret;
 419
 420	if (!hv_dev->channel)
 421		return -ENODEV;
 422
 423	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
 424	if (ret < 0)
 425		return ret;
 426
 427	return sprintf(buf, "%d\n", inbound.current_read_index);
 428}
 429static DEVICE_ATTR_RO(in_read_index);
 430
 431static ssize_t in_write_index_show(struct device *dev,
 432				   struct device_attribute *dev_attr, char *buf)
 433{
 434	struct hv_device *hv_dev = device_to_hv_device(dev);
 435	struct hv_ring_buffer_debug_info inbound;
 436	int ret;
 437
 438	if (!hv_dev->channel)
 439		return -ENODEV;
 440
 441	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
 442	if (ret < 0)
 443		return ret;
 444
 445	return sprintf(buf, "%d\n", inbound.current_write_index);
 446}
 447static DEVICE_ATTR_RO(in_write_index);
 448
 449static ssize_t in_read_bytes_avail_show(struct device *dev,
 450					struct device_attribute *dev_attr,
 451					char *buf)
 452{
 453	struct hv_device *hv_dev = device_to_hv_device(dev);
 454	struct hv_ring_buffer_debug_info inbound;
 455	int ret;
 456
 457	if (!hv_dev->channel)
 458		return -ENODEV;
 459
 460	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
 461	if (ret < 0)
 462		return ret;
 463
 464	return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
 465}
 466static DEVICE_ATTR_RO(in_read_bytes_avail);
 467
 468static ssize_t in_write_bytes_avail_show(struct device *dev,
 469					 struct device_attribute *dev_attr,
 470					 char *buf)
 471{
 472	struct hv_device *hv_dev = device_to_hv_device(dev);
 473	struct hv_ring_buffer_debug_info inbound;
 474	int ret;
 475
 476	if (!hv_dev->channel)
 477		return -ENODEV;
 478
 479	ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
 480	if (ret < 0)
 481		return ret;
 482
 483	return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
 484}
 485static DEVICE_ATTR_RO(in_write_bytes_avail);
 486
 487static ssize_t channel_vp_mapping_show(struct device *dev,
 488				       struct device_attribute *dev_attr,
 489				       char *buf)
 490{
 491	struct hv_device *hv_dev = device_to_hv_device(dev);
 492	struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
 493	unsigned long flags;
 494	int buf_size = PAGE_SIZE, n_written, tot_written;
 495	struct list_head *cur;
 496
 497	if (!channel)
 498		return -ENODEV;
 499
 
 
 500	tot_written = snprintf(buf, buf_size, "%u:%u\n",
 501		channel->offermsg.child_relid, channel->target_cpu);
 502
 503	spin_lock_irqsave(&channel->lock, flags);
 504
 505	list_for_each(cur, &channel->sc_list) {
 506		if (tot_written >= buf_size - 1)
 507			break;
 508
 509		cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
 510		n_written = scnprintf(buf + tot_written,
 511				     buf_size - tot_written,
 512				     "%u:%u\n",
 513				     cur_sc->offermsg.child_relid,
 514				     cur_sc->target_cpu);
 515		tot_written += n_written;
 516	}
 517
 518	spin_unlock_irqrestore(&channel->lock, flags);
 519
 520	return tot_written;
 521}
 522static DEVICE_ATTR_RO(channel_vp_mapping);
 523
 524static ssize_t vendor_show(struct device *dev,
 525			   struct device_attribute *dev_attr,
 526			   char *buf)
 527{
 528	struct hv_device *hv_dev = device_to_hv_device(dev);
 529	return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
 530}
 531static DEVICE_ATTR_RO(vendor);
 532
 533static ssize_t device_show(struct device *dev,
 534			   struct device_attribute *dev_attr,
 535			   char *buf)
 536{
 537	struct hv_device *hv_dev = device_to_hv_device(dev);
 538	return sprintf(buf, "0x%x\n", hv_dev->device_id);
 539}
 540static DEVICE_ATTR_RO(device);
 541
 542static ssize_t driver_override_store(struct device *dev,
 543				     struct device_attribute *attr,
 544				     const char *buf, size_t count)
 545{
 546	struct hv_device *hv_dev = device_to_hv_device(dev);
 547	char *driver_override, *old, *cp;
 548
 549	/* We need to keep extra room for a newline */
 550	if (count >= (PAGE_SIZE - 1))
 551		return -EINVAL;
 552
 553	driver_override = kstrndup(buf, count, GFP_KERNEL);
 554	if (!driver_override)
 555		return -ENOMEM;
 556
 557	cp = strchr(driver_override, '\n');
 558	if (cp)
 559		*cp = '\0';
 560
 561	device_lock(dev);
 562	old = hv_dev->driver_override;
 563	if (strlen(driver_override)) {
 564		hv_dev->driver_override = driver_override;
 565	} else {
 566		kfree(driver_override);
 567		hv_dev->driver_override = NULL;
 568	}
 569	device_unlock(dev);
 570
 571	kfree(old);
 572
 573	return count;
 574}
 575
 576static ssize_t driver_override_show(struct device *dev,
 577				    struct device_attribute *attr, char *buf)
 578{
 579	struct hv_device *hv_dev = device_to_hv_device(dev);
 580	ssize_t len;
 581
 582	device_lock(dev);
 583	len = snprintf(buf, PAGE_SIZE, "%s\n", hv_dev->driver_override);
 584	device_unlock(dev);
 585
 586	return len;
 587}
 588static DEVICE_ATTR_RW(driver_override);
 589
 590/* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
 591static struct attribute *vmbus_dev_attrs[] = {
 592	&dev_attr_id.attr,
 593	&dev_attr_state.attr,
 594	&dev_attr_monitor_id.attr,
 595	&dev_attr_class_id.attr,
 596	&dev_attr_device_id.attr,
 597	&dev_attr_modalias.attr,
 598#ifdef CONFIG_NUMA
 599	&dev_attr_numa_node.attr,
 600#endif
 601	&dev_attr_server_monitor_pending.attr,
 602	&dev_attr_client_monitor_pending.attr,
 603	&dev_attr_server_monitor_latency.attr,
 604	&dev_attr_client_monitor_latency.attr,
 605	&dev_attr_server_monitor_conn_id.attr,
 606	&dev_attr_client_monitor_conn_id.attr,
 607	&dev_attr_out_intr_mask.attr,
 608	&dev_attr_out_read_index.attr,
 609	&dev_attr_out_write_index.attr,
 610	&dev_attr_out_read_bytes_avail.attr,
 611	&dev_attr_out_write_bytes_avail.attr,
 612	&dev_attr_in_intr_mask.attr,
 613	&dev_attr_in_read_index.attr,
 614	&dev_attr_in_write_index.attr,
 615	&dev_attr_in_read_bytes_avail.attr,
 616	&dev_attr_in_write_bytes_avail.attr,
 617	&dev_attr_channel_vp_mapping.attr,
 618	&dev_attr_vendor.attr,
 619	&dev_attr_device.attr,
 620	&dev_attr_driver_override.attr,
 621	NULL,
 622};
 623
 624/*
 625 * Device-level attribute_group callback function. Returns the permission for
 626 * each attribute, and returns 0 if an attribute is not visible.
 627 */
 628static umode_t vmbus_dev_attr_is_visible(struct kobject *kobj,
 629					 struct attribute *attr, int idx)
 630{
 631	struct device *dev = kobj_to_dev(kobj);
 632	const struct hv_device *hv_dev = device_to_hv_device(dev);
 633
 634	/* Hide the monitor attributes if the monitor mechanism is not used. */
 635	if (!hv_dev->channel->offermsg.monitor_allocated &&
 636	    (attr == &dev_attr_monitor_id.attr ||
 637	     attr == &dev_attr_server_monitor_pending.attr ||
 638	     attr == &dev_attr_client_monitor_pending.attr ||
 639	     attr == &dev_attr_server_monitor_latency.attr ||
 640	     attr == &dev_attr_client_monitor_latency.attr ||
 641	     attr == &dev_attr_server_monitor_conn_id.attr ||
 642	     attr == &dev_attr_client_monitor_conn_id.attr))
 643		return 0;
 644
 645	return attr->mode;
 646}
 647
 648static const struct attribute_group vmbus_dev_group = {
 649	.attrs = vmbus_dev_attrs,
 650	.is_visible = vmbus_dev_attr_is_visible
 651};
 652__ATTRIBUTE_GROUPS(vmbus_dev);
 653
 654/*
 655 * vmbus_uevent - add uevent for our device
 656 *
 657 * This routine is invoked when a device is added or removed on the vmbus to
 658 * generate a uevent to udev in the userspace. The udev will then look at its
 659 * rule and the uevent generated here to load the appropriate driver
 660 *
 661 * The alias string will be of the form vmbus:guid where guid is the string
 662 * representation of the device guid (each byte of the guid will be
 663 * represented with two hex characters.
 664 */
 665static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
 666{
 667	struct hv_device *dev = device_to_hv_device(device);
 668	int ret;
 669	char alias_name[VMBUS_ALIAS_LEN + 1];
 670
 671	print_alias_name(dev, alias_name);
 672	ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
 673	return ret;
 674}
 675
 676static const struct hv_vmbus_device_id *
 677hv_vmbus_dev_match(const struct hv_vmbus_device_id *id, const guid_t *guid)
 678{
 679	if (id == NULL)
 680		return NULL; /* empty device table */
 681
 682	for (; !guid_is_null(&id->guid); id++)
 683		if (guid_equal(&id->guid, guid))
 684			return id;
 685
 686	return NULL;
 687}
 688
 689static const struct hv_vmbus_device_id *
 690hv_vmbus_dynid_match(struct hv_driver *drv, const guid_t *guid)
 691{
 692	const struct hv_vmbus_device_id *id = NULL;
 693	struct vmbus_dynid *dynid;
 694
 695	spin_lock(&drv->dynids.lock);
 696	list_for_each_entry(dynid, &drv->dynids.list, node) {
 697		if (guid_equal(&dynid->id.guid, guid)) {
 698			id = &dynid->id;
 699			break;
 700		}
 701	}
 702	spin_unlock(&drv->dynids.lock);
 703
 704	return id;
 705}
 706
 707static const struct hv_vmbus_device_id vmbus_device_null;
 708
 709/*
 710 * Return a matching hv_vmbus_device_id pointer.
 711 * If there is no match, return NULL.
 712 */
 713static const struct hv_vmbus_device_id *hv_vmbus_get_id(struct hv_driver *drv,
 714							struct hv_device *dev)
 715{
 716	const guid_t *guid = &dev->dev_type;
 717	const struct hv_vmbus_device_id *id;
 718
 719	/* When driver_override is set, only bind to the matching driver */
 720	if (dev->driver_override && strcmp(dev->driver_override, drv->name))
 721		return NULL;
 722
 723	/* Look at the dynamic ids first, before the static ones */
 724	id = hv_vmbus_dynid_match(drv, guid);
 725	if (!id)
 726		id = hv_vmbus_dev_match(drv->id_table, guid);
 727
 728	/* driver_override will always match, send a dummy id */
 729	if (!id && dev->driver_override)
 730		id = &vmbus_device_null;
 731
 732	return id;
 733}
 734
 735/* vmbus_add_dynid - add a new device ID to this driver and re-probe devices */
 736static int vmbus_add_dynid(struct hv_driver *drv, guid_t *guid)
 737{
 738	struct vmbus_dynid *dynid;
 739
 740	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
 741	if (!dynid)
 742		return -ENOMEM;
 743
 744	dynid->id.guid = *guid;
 745
 746	spin_lock(&drv->dynids.lock);
 747	list_add_tail(&dynid->node, &drv->dynids.list);
 748	spin_unlock(&drv->dynids.lock);
 749
 750	return driver_attach(&drv->driver);
 751}
 752
 753static void vmbus_free_dynids(struct hv_driver *drv)
 754{
 755	struct vmbus_dynid *dynid, *n;
 756
 757	spin_lock(&drv->dynids.lock);
 758	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
 759		list_del(&dynid->node);
 760		kfree(dynid);
 761	}
 762	spin_unlock(&drv->dynids.lock);
 763}
 764
 765/*
 766 * store_new_id - sysfs frontend to vmbus_add_dynid()
 767 *
 768 * Allow GUIDs to be added to an existing driver via sysfs.
 769 */
 770static ssize_t new_id_store(struct device_driver *driver, const char *buf,
 771			    size_t count)
 772{
 773	struct hv_driver *drv = drv_to_hv_drv(driver);
 774	guid_t guid;
 775	ssize_t retval;
 776
 777	retval = guid_parse(buf, &guid);
 778	if (retval)
 779		return retval;
 780
 781	if (hv_vmbus_dynid_match(drv, &guid))
 782		return -EEXIST;
 783
 784	retval = vmbus_add_dynid(drv, &guid);
 785	if (retval)
 786		return retval;
 787	return count;
 788}
 789static DRIVER_ATTR_WO(new_id);
 790
 791/*
 792 * store_remove_id - remove a PCI device ID from this driver
 793 *
 794 * Removes a dynamic pci device ID to this driver.
 795 */
 796static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
 797			       size_t count)
 798{
 799	struct hv_driver *drv = drv_to_hv_drv(driver);
 800	struct vmbus_dynid *dynid, *n;
 801	guid_t guid;
 802	ssize_t retval;
 803
 804	retval = guid_parse(buf, &guid);
 805	if (retval)
 806		return retval;
 807
 808	retval = -ENODEV;
 809	spin_lock(&drv->dynids.lock);
 810	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
 811		struct hv_vmbus_device_id *id = &dynid->id;
 812
 813		if (guid_equal(&id->guid, &guid)) {
 814			list_del(&dynid->node);
 815			kfree(dynid);
 816			retval = count;
 817			break;
 818		}
 819	}
 820	spin_unlock(&drv->dynids.lock);
 821
 822	return retval;
 823}
 824static DRIVER_ATTR_WO(remove_id);
 825
 826static struct attribute *vmbus_drv_attrs[] = {
 827	&driver_attr_new_id.attr,
 828	&driver_attr_remove_id.attr,
 829	NULL,
 830};
 831ATTRIBUTE_GROUPS(vmbus_drv);
 832
 833
 834/*
 835 * vmbus_match - Attempt to match the specified device to the specified driver
 836 */
 837static int vmbus_match(struct device *device, struct device_driver *driver)
 838{
 839	struct hv_driver *drv = drv_to_hv_drv(driver);
 840	struct hv_device *hv_dev = device_to_hv_device(device);
 841
 842	/* The hv_sock driver handles all hv_sock offers. */
 843	if (is_hvsock_channel(hv_dev->channel))
 844		return drv->hvsock;
 845
 846	if (hv_vmbus_get_id(drv, hv_dev))
 847		return 1;
 848
 849	return 0;
 850}
 851
 852/*
 853 * vmbus_probe - Add the new vmbus's child device
 854 */
 855static int vmbus_probe(struct device *child_device)
 856{
 857	int ret = 0;
 858	struct hv_driver *drv =
 859			drv_to_hv_drv(child_device->driver);
 860	struct hv_device *dev = device_to_hv_device(child_device);
 861	const struct hv_vmbus_device_id *dev_id;
 862
 863	dev_id = hv_vmbus_get_id(drv, dev);
 864	if (drv->probe) {
 865		ret = drv->probe(dev, dev_id);
 866		if (ret != 0)
 867			pr_err("probe failed for device %s (%d)\n",
 868			       dev_name(child_device), ret);
 869
 870	} else {
 871		pr_err("probe not set for driver %s\n",
 872		       dev_name(child_device));
 873		ret = -ENODEV;
 874	}
 875	return ret;
 876}
 877
 878/*
 879 * vmbus_remove - Remove a vmbus device
 880 */
 881static int vmbus_remove(struct device *child_device)
 882{
 883	struct hv_driver *drv;
 884	struct hv_device *dev = device_to_hv_device(child_device);
 885
 886	if (child_device->driver) {
 887		drv = drv_to_hv_drv(child_device->driver);
 888		if (drv->remove)
 889			drv->remove(dev);
 890	}
 891
 892	return 0;
 893}
 894
 895
 896/*
 897 * vmbus_shutdown - Shutdown a vmbus device
 898 */
 899static void vmbus_shutdown(struct device *child_device)
 900{
 901	struct hv_driver *drv;
 902	struct hv_device *dev = device_to_hv_device(child_device);
 903
 904
 905	/* The device may not be attached yet */
 906	if (!child_device->driver)
 907		return;
 908
 909	drv = drv_to_hv_drv(child_device->driver);
 910
 911	if (drv->shutdown)
 912		drv->shutdown(dev);
 913}
 914
 915#ifdef CONFIG_PM_SLEEP
 916/*
 917 * vmbus_suspend - Suspend a vmbus device
 918 */
 919static int vmbus_suspend(struct device *child_device)
 920{
 921	struct hv_driver *drv;
 922	struct hv_device *dev = device_to_hv_device(child_device);
 923
 924	/* The device may not be attached yet */
 925	if (!child_device->driver)
 926		return 0;
 927
 928	drv = drv_to_hv_drv(child_device->driver);
 929	if (!drv->suspend)
 930		return -EOPNOTSUPP;
 931
 932	return drv->suspend(dev);
 933}
 934
 935/*
 936 * vmbus_resume - Resume a vmbus device
 937 */
 938static int vmbus_resume(struct device *child_device)
 939{
 940	struct hv_driver *drv;
 941	struct hv_device *dev = device_to_hv_device(child_device);
 942
 943	/* The device may not be attached yet */
 944	if (!child_device->driver)
 945		return 0;
 946
 947	drv = drv_to_hv_drv(child_device->driver);
 948	if (!drv->resume)
 949		return -EOPNOTSUPP;
 950
 951	return drv->resume(dev);
 952}
 
 
 
 953#endif /* CONFIG_PM_SLEEP */
 954
 955/*
 956 * vmbus_device_release - Final callback release of the vmbus child device
 957 */
 958static void vmbus_device_release(struct device *device)
 959{
 960	struct hv_device *hv_dev = device_to_hv_device(device);
 961	struct vmbus_channel *channel = hv_dev->channel;
 962
 
 
 963	mutex_lock(&vmbus_connection.channel_mutex);
 964	hv_process_channel_removal(channel);
 965	mutex_unlock(&vmbus_connection.channel_mutex);
 966	kfree(hv_dev);
 967}
 968
 969/*
 970 * Note: we must use SET_NOIRQ_SYSTEM_SLEEP_PM_OPS rather than
 971 * SET_SYSTEM_SLEEP_PM_OPS: see the comment before vmbus_bus_pm.
 
 
 
 
 
 972 */
 
 973static const struct dev_pm_ops vmbus_pm = {
 974	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(vmbus_suspend, vmbus_resume)
 
 
 
 
 
 975};
 976
 977/* The one and only one */
 978static struct bus_type  hv_bus = {
 979	.name =		"vmbus",
 980	.match =		vmbus_match,
 981	.shutdown =		vmbus_shutdown,
 982	.remove =		vmbus_remove,
 983	.probe =		vmbus_probe,
 984	.uevent =		vmbus_uevent,
 985	.dev_groups =		vmbus_dev_groups,
 986	.drv_groups =		vmbus_drv_groups,
 987	.pm =			&vmbus_pm,
 988};
 989
 990struct onmessage_work_context {
 991	struct work_struct work;
 992	struct hv_message msg;
 
 
 
 993};
 994
 995static void vmbus_onmessage_work(struct work_struct *work)
 996{
 997	struct onmessage_work_context *ctx;
 998
 999	/* Do not process messages if we're in DISCONNECTED state */
1000	if (vmbus_connection.conn_state == DISCONNECTED)
1001		return;
1002
1003	ctx = container_of(work, struct onmessage_work_context,
1004			   work);
1005	vmbus_onmessage(&ctx->msg);
 
1006	kfree(ctx);
1007}
1008
1009void vmbus_on_msg_dpc(unsigned long data)
1010{
1011	struct hv_per_cpu_context *hv_cpu = (void *)data;
1012	void *page_addr = hv_cpu->synic_message_page;
1013	struct hv_message *msg = (struct hv_message *)page_addr +
1014				  VMBUS_MESSAGE_SINT;
1015	struct vmbus_channel_message_header *hdr;
1016	const struct vmbus_channel_message_table_entry *entry;
1017	struct onmessage_work_context *ctx;
1018	u32 message_type = msg->header.message_type;
1019
 
 
 
 
 
 
 
1020	if (message_type == HVMSG_NONE)
1021		/* no msg */
1022		return;
1023
1024	hdr = (struct vmbus_channel_message_header *)msg->u.payload;
1025
1026	trace_vmbus_on_msg_dpc(hdr);
1027
1028	if (hdr->msgtype >= CHANNELMSG_COUNT) {
1029		WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
1030		goto msg_handled;
1031	}
1032
 
 
 
 
 
 
1033	entry = &channel_message_table[hdr->msgtype];
 
 
 
 
 
 
 
 
 
 
1034	if (entry->handler_type	== VMHT_BLOCKING) {
1035		ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
 
1036		if (ctx == NULL)
1037			return;
1038
1039		INIT_WORK(&ctx->work, vmbus_onmessage_work);
1040		memcpy(&ctx->msg, msg, sizeof(*msg));
 
1041
1042		/*
1043		 * The host can generate a rescind message while we
1044		 * may still be handling the original offer. We deal with
1045		 * this condition by ensuring the processing is done on the
1046		 * same CPU.
 
1047		 */
1048		switch (hdr->msgtype) {
1049		case CHANNELMSG_RESCIND_CHANNELOFFER:
1050			/*
1051			 * If we are handling the rescind message;
1052			 * schedule the work on the global work queue.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1053			 */
1054			schedule_work_on(vmbus_connection.connect_cpu,
1055					 &ctx->work);
1056			break;
1057
1058		case CHANNELMSG_OFFERCHANNEL:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1059			atomic_inc(&vmbus_connection.offer_in_progress);
1060			queue_work_on(vmbus_connection.connect_cpu,
1061				      vmbus_connection.work_queue,
1062				      &ctx->work);
1063			break;
1064
1065		default:
1066			queue_work(vmbus_connection.work_queue, &ctx->work);
1067		}
1068	} else
1069		entry->message_handler(hdr);
1070
1071msg_handled:
1072	vmbus_signal_eom(msg, message_type);
1073}
1074
1075#ifdef CONFIG_PM_SLEEP
1076/*
1077 * Fake RESCIND_CHANNEL messages to clean up hv_sock channels by force for
1078 * hibernation, because hv_sock connections can not persist across hibernation.
1079 */
1080static void vmbus_force_channel_rescinded(struct vmbus_channel *channel)
1081{
1082	struct onmessage_work_context *ctx;
1083	struct vmbus_channel_rescind_offer *rescind;
1084
1085	WARN_ON(!is_hvsock_channel(channel));
1086
1087	/*
1088	 * sizeof(*ctx) is small and the allocation should really not fail,
1089	 * otherwise the state of the hv_sock connections ends up in limbo.
1090	 */
1091	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL | __GFP_NOFAIL);
 
1092
1093	/*
1094	 * So far, these are not really used by Linux. Just set them to the
1095	 * reasonable values conforming to the definitions of the fields.
1096	 */
1097	ctx->msg.header.message_type = 1;
1098	ctx->msg.header.payload_size = sizeof(*rescind);
1099
1100	/* These values are actually used by Linux. */
1101	rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.u.payload;
1102	rescind->header.msgtype = CHANNELMSG_RESCIND_CHANNELOFFER;
1103	rescind->child_relid = channel->offermsg.child_relid;
1104
1105	INIT_WORK(&ctx->work, vmbus_onmessage_work);
1106
1107	queue_work_on(vmbus_connection.connect_cpu,
1108		      vmbus_connection.work_queue,
1109		      &ctx->work);
1110}
1111#endif /* CONFIG_PM_SLEEP */
1112
1113/*
1114 * Direct callback for channels using other deferred processing
1115 */
1116static void vmbus_channel_isr(struct vmbus_channel *channel)
1117{
1118	void (*callback_fn)(void *);
1119
1120	callback_fn = READ_ONCE(channel->onchannel_callback);
1121	if (likely(callback_fn != NULL))
1122		(*callback_fn)(channel->channel_callback_context);
1123}
1124
1125/*
1126 * Schedule all channels with events pending
1127 */
1128static void vmbus_chan_sched(struct hv_per_cpu_context *hv_cpu)
1129{
1130	unsigned long *recv_int_page;
1131	u32 maxbits, relid;
1132
1133	if (vmbus_proto_version < VERSION_WIN8) {
1134		maxbits = MAX_NUM_CHANNELS_SUPPORTED;
1135		recv_int_page = vmbus_connection.recv_int_page;
1136	} else {
1137		/*
1138		 * When the host is win8 and beyond, the event page
1139		 * can be directly checked to get the id of the channel
1140		 * that has the interrupt pending.
1141		 */
1142		void *page_addr = hv_cpu->synic_event_page;
1143		union hv_synic_event_flags *event
1144			= (union hv_synic_event_flags *)page_addr +
1145						 VMBUS_MESSAGE_SINT;
1146
1147		maxbits = HV_EVENT_FLAGS_COUNT;
1148		recv_int_page = event->flags;
1149	}
1150
1151	if (unlikely(!recv_int_page))
1152		return;
1153
1154	for_each_set_bit(relid, recv_int_page, maxbits) {
 
1155		struct vmbus_channel *channel;
1156
1157		if (!sync_test_and_clear_bit(relid, recv_int_page))
1158			continue;
1159
1160		/* Special case - vmbus channel protocol msg */
1161		if (relid == 0)
1162			continue;
1163
 
 
 
 
 
 
1164		rcu_read_lock();
1165
1166		/* Find channel based on relid */
1167		list_for_each_entry_rcu(channel, &hv_cpu->chan_list, percpu_list) {
1168			if (channel->offermsg.child_relid != relid)
1169				continue;
1170
1171			if (channel->rescind)
1172				continue;
1173
1174			trace_vmbus_chan_sched(channel);
 
 
 
 
 
 
 
1175
1176			++channel->interrupts;
 
 
1177
1178			switch (channel->callback_mode) {
1179			case HV_CALL_ISR:
1180				vmbus_channel_isr(channel);
1181				break;
1182
1183			case HV_CALL_BATCHED:
1184				hv_begin_read(&channel->inbound);
1185				/* fallthrough */
1186			case HV_CALL_DIRECT:
1187				tasklet_schedule(&channel->callback_event);
1188			}
 
 
 
1189		}
1190
 
 
 
1191		rcu_read_unlock();
1192	}
1193}
1194
1195static void vmbus_isr(void)
1196{
1197	struct hv_per_cpu_context *hv_cpu
1198		= this_cpu_ptr(hv_context.cpu_context);
1199	void *page_addr = hv_cpu->synic_event_page;
1200	struct hv_message *msg;
1201	union hv_synic_event_flags *event;
1202	bool handled = false;
1203
1204	if (unlikely(page_addr == NULL))
1205		return;
1206
1207	event = (union hv_synic_event_flags *)page_addr +
1208					 VMBUS_MESSAGE_SINT;
1209	/*
1210	 * Check for events before checking for messages. This is the order
1211	 * in which events and messages are checked in Windows guests on
1212	 * Hyper-V, and the Windows team suggested we do the same.
1213	 */
1214
1215	if ((vmbus_proto_version == VERSION_WS2008) ||
1216		(vmbus_proto_version == VERSION_WIN7)) {
1217
1218		/* Since we are a child, we only need to check bit 0 */
1219		if (sync_test_and_clear_bit(0, event->flags))
1220			handled = true;
1221	} else {
1222		/*
1223		 * Our host is win8 or above. The signaling mechanism
1224		 * has changed and we can directly look at the event page.
1225		 * If bit n is set then we have an interrup on the channel
1226		 * whose id is n.
1227		 */
1228		handled = true;
1229	}
1230
1231	if (handled)
1232		vmbus_chan_sched(hv_cpu);
1233
1234	page_addr = hv_cpu->synic_message_page;
1235	msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
1236
1237	/* Check if there are actual msgs to be processed */
1238	if (msg->header.message_type != HVMSG_NONE) {
1239		if (msg->header.message_type == HVMSG_TIMER_EXPIRED) {
1240			hv_stimer0_isr();
1241			vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED);
1242		} else
1243			tasklet_schedule(&hv_cpu->msg_dpc);
1244	}
1245
1246	add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
1247}
1248
1249/*
1250 * Boolean to control whether to report panic messages over Hyper-V.
1251 *
1252 * It can be set via /proc/sys/kernel/hyperv/record_panic_msg
1253 */
1254static int sysctl_record_panic_msg = 1;
1255
1256/*
1257 * Callback from kmsg_dump. Grab as much as possible from the end of the kmsg
1258 * buffer and call into Hyper-V to transfer the data.
1259 */
1260static void hv_kmsg_dump(struct kmsg_dumper *dumper,
1261			 enum kmsg_dump_reason reason)
1262{
1263	size_t bytes_written;
1264	phys_addr_t panic_pa;
1265
1266	/* We are only interested in panics. */
1267	if ((reason != KMSG_DUMP_PANIC) || (!sysctl_record_panic_msg))
1268		return;
1269
1270	panic_pa = virt_to_phys(hv_panic_page);
1271
1272	/*
1273	 * Write dump contents to the page. No need to synchronize; panic should
1274	 * be single-threaded.
1275	 */
1276	kmsg_dump_get_buffer(dumper, true, hv_panic_page, PAGE_SIZE,
1277			     &bytes_written);
1278	if (bytes_written)
1279		hyperv_report_panic_msg(panic_pa, bytes_written);
1280}
1281
1282static struct kmsg_dumper hv_kmsg_dumper = {
1283	.dump = hv_kmsg_dump,
1284};
1285
1286static struct ctl_table_header *hv_ctl_table_hdr;
1287
1288/*
1289 * sysctl option to allow the user to control whether kmsg data should be
1290 * reported to Hyper-V on panic.
1291 */
1292static struct ctl_table hv_ctl_table[] = {
1293	{
1294		.procname       = "hyperv_record_panic_msg",
1295		.data           = &sysctl_record_panic_msg,
1296		.maxlen         = sizeof(int),
1297		.mode           = 0644,
1298		.proc_handler   = proc_dointvec_minmax,
1299		.extra1		= SYSCTL_ZERO,
1300		.extra2		= SYSCTL_ONE
1301	},
1302	{}
1303};
1304
1305static struct ctl_table hv_root_table[] = {
1306	{
1307		.procname	= "kernel",
1308		.mode		= 0555,
1309		.child		= hv_ctl_table
1310	},
1311	{}
1312};
1313
1314/*
1315 * vmbus_bus_init -Main vmbus driver initialization routine.
1316 *
1317 * Here, we
1318 *	- initialize the vmbus driver context
1319 *	- invoke the vmbus hv main init routine
1320 *	- retrieve the channel offers
1321 */
1322static int vmbus_bus_init(void)
1323{
1324	int ret;
1325
1326	/* Hypervisor initialization...setup hypercall page..etc */
1327	ret = hv_init();
1328	if (ret != 0) {
1329		pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
1330		return ret;
1331	}
1332
1333	ret = bus_register(&hv_bus);
1334	if (ret)
1335		return ret;
1336
1337	hv_setup_vmbus_irq(vmbus_isr);
1338
1339	ret = hv_synic_alloc();
1340	if (ret)
1341		goto err_alloc;
1342
1343	ret = hv_stimer_alloc(VMBUS_MESSAGE_SINT);
1344	if (ret < 0)
1345		goto err_alloc;
1346
1347	/*
1348	 * Initialize the per-cpu interrupt state and stimer state.
1349	 * Then connect to the host.
1350	 */
1351	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online",
1352				hv_synic_init, hv_synic_cleanup);
1353	if (ret < 0)
1354		goto err_cpuhp;
1355	hyperv_cpuhp_online = ret;
1356
1357	ret = vmbus_connect();
1358	if (ret)
1359		goto err_connect;
1360
1361	/*
1362	 * Only register if the crash MSRs are available
1363	 */
1364	if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
1365		u64 hyperv_crash_ctl;
1366		/*
1367		 * Sysctl registration is not fatal, since by default
1368		 * reporting is enabled.
1369		 */
1370		hv_ctl_table_hdr = register_sysctl_table(hv_root_table);
1371		if (!hv_ctl_table_hdr)
1372			pr_err("Hyper-V: sysctl table register error");
1373
1374		/*
1375		 * Register for panic kmsg callback only if the right
1376		 * capability is supported by the hypervisor.
1377		 */
1378		hv_get_crash_ctl(hyperv_crash_ctl);
1379		if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) {
1380			hv_panic_page = (void *)get_zeroed_page(GFP_KERNEL);
1381			if (hv_panic_page) {
1382				ret = kmsg_dump_register(&hv_kmsg_dumper);
1383				if (ret)
1384					pr_err("Hyper-V: kmsg dump register "
1385						"error 0x%x\n", ret);
 
 
 
 
1386			} else
1387				pr_err("Hyper-V: panic message page memory "
1388					"allocation failed");
1389		}
1390
1391		register_die_notifier(&hyperv_die_block);
1392		atomic_notifier_chain_register(&panic_notifier_list,
1393					       &hyperv_panic_block);
1394	}
1395
 
 
 
 
 
 
 
 
1396	vmbus_request_offers();
1397
1398	return 0;
1399
1400err_connect:
1401	cpuhp_remove_state(hyperv_cpuhp_online);
1402err_cpuhp:
1403	hv_stimer_free();
1404err_alloc:
1405	hv_synic_free();
 
1406	hv_remove_vmbus_irq();
1407
1408	bus_unregister(&hv_bus);
1409	free_page((unsigned long)hv_panic_page);
1410	unregister_sysctl_table(hv_ctl_table_hdr);
1411	hv_ctl_table_hdr = NULL;
1412	return ret;
1413}
1414
1415/**
1416 * __vmbus_child_driver_register() - Register a vmbus's driver
1417 * @hv_driver: Pointer to driver structure you want to register
1418 * @owner: owner module of the drv
1419 * @mod_name: module name string
1420 *
1421 * Registers the given driver with Linux through the 'driver_register()' call
1422 * and sets up the hyper-v vmbus handling for this driver.
1423 * It will return the state of the 'driver_register()' call.
1424 *
1425 */
1426int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
1427{
1428	int ret;
1429
1430	pr_info("registering driver %s\n", hv_driver->name);
1431
1432	ret = vmbus_exists();
1433	if (ret < 0)
1434		return ret;
1435
1436	hv_driver->driver.name = hv_driver->name;
1437	hv_driver->driver.owner = owner;
1438	hv_driver->driver.mod_name = mod_name;
1439	hv_driver->driver.bus = &hv_bus;
1440
1441	spin_lock_init(&hv_driver->dynids.lock);
1442	INIT_LIST_HEAD(&hv_driver->dynids.list);
1443
1444	ret = driver_register(&hv_driver->driver);
1445
1446	return ret;
1447}
1448EXPORT_SYMBOL_GPL(__vmbus_driver_register);
1449
1450/**
1451 * vmbus_driver_unregister() - Unregister a vmbus's driver
1452 * @hv_driver: Pointer to driver structure you want to
1453 *             un-register
1454 *
1455 * Un-register the given driver that was previous registered with a call to
1456 * vmbus_driver_register()
1457 */
1458void vmbus_driver_unregister(struct hv_driver *hv_driver)
1459{
1460	pr_info("unregistering driver %s\n", hv_driver->name);
1461
1462	if (!vmbus_exists()) {
1463		driver_unregister(&hv_driver->driver);
1464		vmbus_free_dynids(hv_driver);
1465	}
1466}
1467EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
1468
1469
1470/*
1471 * Called when last reference to channel is gone.
1472 */
1473static void vmbus_chan_release(struct kobject *kobj)
1474{
1475	struct vmbus_channel *channel
1476		= container_of(kobj, struct vmbus_channel, kobj);
1477
1478	kfree_rcu(channel, rcu);
1479}
1480
1481struct vmbus_chan_attribute {
1482	struct attribute attr;
1483	ssize_t (*show)(struct vmbus_channel *chan, char *buf);
1484	ssize_t (*store)(struct vmbus_channel *chan,
1485			 const char *buf, size_t count);
1486};
1487#define VMBUS_CHAN_ATTR(_name, _mode, _show, _store) \
1488	struct vmbus_chan_attribute chan_attr_##_name \
1489		= __ATTR(_name, _mode, _show, _store)
1490#define VMBUS_CHAN_ATTR_RW(_name) \
1491	struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RW(_name)
1492#define VMBUS_CHAN_ATTR_RO(_name) \
1493	struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RO(_name)
1494#define VMBUS_CHAN_ATTR_WO(_name) \
1495	struct vmbus_chan_attribute chan_attr_##_name = __ATTR_WO(_name)
1496
1497static ssize_t vmbus_chan_attr_show(struct kobject *kobj,
1498				    struct attribute *attr, char *buf)
1499{
1500	const struct vmbus_chan_attribute *attribute
1501		= container_of(attr, struct vmbus_chan_attribute, attr);
1502	struct vmbus_channel *chan
1503		= container_of(kobj, struct vmbus_channel, kobj);
1504
1505	if (!attribute->show)
1506		return -EIO;
1507
1508	return attribute->show(chan, buf);
1509}
1510
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1511static const struct sysfs_ops vmbus_chan_sysfs_ops = {
1512	.show = vmbus_chan_attr_show,
 
1513};
1514
1515static ssize_t out_mask_show(struct vmbus_channel *channel, char *buf)
1516{
1517	struct hv_ring_buffer_info *rbi = &channel->outbound;
1518	ssize_t ret;
1519
1520	mutex_lock(&rbi->ring_buffer_mutex);
1521	if (!rbi->ring_buffer) {
1522		mutex_unlock(&rbi->ring_buffer_mutex);
1523		return -EINVAL;
1524	}
1525
1526	ret = sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
1527	mutex_unlock(&rbi->ring_buffer_mutex);
1528	return ret;
1529}
1530static VMBUS_CHAN_ATTR_RO(out_mask);
1531
1532static ssize_t in_mask_show(struct vmbus_channel *channel, char *buf)
1533{
1534	struct hv_ring_buffer_info *rbi = &channel->inbound;
1535	ssize_t ret;
1536
1537	mutex_lock(&rbi->ring_buffer_mutex);
1538	if (!rbi->ring_buffer) {
1539		mutex_unlock(&rbi->ring_buffer_mutex);
1540		return -EINVAL;
1541	}
1542
1543	ret = sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
1544	mutex_unlock(&rbi->ring_buffer_mutex);
1545	return ret;
1546}
1547static VMBUS_CHAN_ATTR_RO(in_mask);
1548
1549static ssize_t read_avail_show(struct vmbus_channel *channel, char *buf)
1550{
1551	struct hv_ring_buffer_info *rbi = &channel->inbound;
1552	ssize_t ret;
1553
1554	mutex_lock(&rbi->ring_buffer_mutex);
1555	if (!rbi->ring_buffer) {
1556		mutex_unlock(&rbi->ring_buffer_mutex);
1557		return -EINVAL;
1558	}
1559
1560	ret = sprintf(buf, "%u\n", hv_get_bytes_to_read(rbi));
1561	mutex_unlock(&rbi->ring_buffer_mutex);
1562	return ret;
1563}
1564static VMBUS_CHAN_ATTR_RO(read_avail);
1565
1566static ssize_t write_avail_show(struct vmbus_channel *channel, char *buf)
1567{
1568	struct hv_ring_buffer_info *rbi = &channel->outbound;
1569	ssize_t ret;
1570
1571	mutex_lock(&rbi->ring_buffer_mutex);
1572	if (!rbi->ring_buffer) {
1573		mutex_unlock(&rbi->ring_buffer_mutex);
1574		return -EINVAL;
1575	}
1576
1577	ret = sprintf(buf, "%u\n", hv_get_bytes_to_write(rbi));
1578	mutex_unlock(&rbi->ring_buffer_mutex);
1579	return ret;
1580}
1581static VMBUS_CHAN_ATTR_RO(write_avail);
1582
1583static ssize_t show_target_cpu(struct vmbus_channel *channel, char *buf)
1584{
1585	return sprintf(buf, "%u\n", channel->target_cpu);
1586}
1587static VMBUS_CHAN_ATTR(cpu, S_IRUGO, show_target_cpu, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1588
1589static ssize_t channel_pending_show(struct vmbus_channel *channel,
1590				    char *buf)
1591{
1592	return sprintf(buf, "%d\n",
1593		       channel_pending(channel,
1594				       vmbus_connection.monitor_pages[1]));
1595}
1596static VMBUS_CHAN_ATTR(pending, S_IRUGO, channel_pending_show, NULL);
1597
1598static ssize_t channel_latency_show(struct vmbus_channel *channel,
1599				    char *buf)
1600{
1601	return sprintf(buf, "%d\n",
1602		       channel_latency(channel,
1603				       vmbus_connection.monitor_pages[1]));
1604}
1605static VMBUS_CHAN_ATTR(latency, S_IRUGO, channel_latency_show, NULL);
1606
1607static ssize_t channel_interrupts_show(struct vmbus_channel *channel, char *buf)
1608{
1609	return sprintf(buf, "%llu\n", channel->interrupts);
1610}
1611static VMBUS_CHAN_ATTR(interrupts, S_IRUGO, channel_interrupts_show, NULL);
1612
1613static ssize_t channel_events_show(struct vmbus_channel *channel, char *buf)
1614{
1615	return sprintf(buf, "%llu\n", channel->sig_events);
1616}
1617static VMBUS_CHAN_ATTR(events, S_IRUGO, channel_events_show, NULL);
1618
1619static ssize_t channel_intr_in_full_show(struct vmbus_channel *channel,
1620					 char *buf)
1621{
1622	return sprintf(buf, "%llu\n",
1623		       (unsigned long long)channel->intr_in_full);
1624}
1625static VMBUS_CHAN_ATTR(intr_in_full, 0444, channel_intr_in_full_show, NULL);
1626
1627static ssize_t channel_intr_out_empty_show(struct vmbus_channel *channel,
1628					   char *buf)
1629{
1630	return sprintf(buf, "%llu\n",
1631		       (unsigned long long)channel->intr_out_empty);
1632}
1633static VMBUS_CHAN_ATTR(intr_out_empty, 0444, channel_intr_out_empty_show, NULL);
1634
1635static ssize_t channel_out_full_first_show(struct vmbus_channel *channel,
1636					   char *buf)
1637{
1638	return sprintf(buf, "%llu\n",
1639		       (unsigned long long)channel->out_full_first);
1640}
1641static VMBUS_CHAN_ATTR(out_full_first, 0444, channel_out_full_first_show, NULL);
1642
1643static ssize_t channel_out_full_total_show(struct vmbus_channel *channel,
1644					   char *buf)
1645{
1646	return sprintf(buf, "%llu\n",
1647		       (unsigned long long)channel->out_full_total);
1648}
1649static VMBUS_CHAN_ATTR(out_full_total, 0444, channel_out_full_total_show, NULL);
1650
1651static ssize_t subchannel_monitor_id_show(struct vmbus_channel *channel,
1652					  char *buf)
1653{
1654	return sprintf(buf, "%u\n", channel->offermsg.monitorid);
1655}
1656static VMBUS_CHAN_ATTR(monitor_id, S_IRUGO, subchannel_monitor_id_show, NULL);
1657
1658static ssize_t subchannel_id_show(struct vmbus_channel *channel,
1659				  char *buf)
1660{
1661	return sprintf(buf, "%u\n",
1662		       channel->offermsg.offer.sub_channel_index);
1663}
1664static VMBUS_CHAN_ATTR_RO(subchannel_id);
1665
1666static struct attribute *vmbus_chan_attrs[] = {
1667	&chan_attr_out_mask.attr,
1668	&chan_attr_in_mask.attr,
1669	&chan_attr_read_avail.attr,
1670	&chan_attr_write_avail.attr,
1671	&chan_attr_cpu.attr,
1672	&chan_attr_pending.attr,
1673	&chan_attr_latency.attr,
1674	&chan_attr_interrupts.attr,
1675	&chan_attr_events.attr,
1676	&chan_attr_intr_in_full.attr,
1677	&chan_attr_intr_out_empty.attr,
1678	&chan_attr_out_full_first.attr,
1679	&chan_attr_out_full_total.attr,
1680	&chan_attr_monitor_id.attr,
1681	&chan_attr_subchannel_id.attr,
1682	NULL
1683};
1684
1685/*
1686 * Channel-level attribute_group callback function. Returns the permission for
1687 * each attribute, and returns 0 if an attribute is not visible.
1688 */
1689static umode_t vmbus_chan_attr_is_visible(struct kobject *kobj,
1690					  struct attribute *attr, int idx)
1691{
1692	const struct vmbus_channel *channel =
1693		container_of(kobj, struct vmbus_channel, kobj);
1694
1695	/* Hide the monitor attributes if the monitor mechanism is not used. */
1696	if (!channel->offermsg.monitor_allocated &&
1697	    (attr == &chan_attr_pending.attr ||
1698	     attr == &chan_attr_latency.attr ||
1699	     attr == &chan_attr_monitor_id.attr))
1700		return 0;
1701
1702	return attr->mode;
1703}
1704
1705static struct attribute_group vmbus_chan_group = {
1706	.attrs = vmbus_chan_attrs,
1707	.is_visible = vmbus_chan_attr_is_visible
1708};
1709
1710static struct kobj_type vmbus_chan_ktype = {
1711	.sysfs_ops = &vmbus_chan_sysfs_ops,
1712	.release = vmbus_chan_release,
1713};
1714
1715/*
1716 * vmbus_add_channel_kobj - setup a sub-directory under device/channels
1717 */
1718int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
1719{
1720	const struct device *device = &dev->device;
1721	struct kobject *kobj = &channel->kobj;
1722	u32 relid = channel->offermsg.child_relid;
1723	int ret;
1724
1725	kobj->kset = dev->channels_kset;
1726	ret = kobject_init_and_add(kobj, &vmbus_chan_ktype, NULL,
1727				   "%u", relid);
1728	if (ret)
1729		return ret;
1730
1731	ret = sysfs_create_group(kobj, &vmbus_chan_group);
1732
1733	if (ret) {
1734		/*
1735		 * The calling functions' error handling paths will cleanup the
1736		 * empty channel directory.
1737		 */
1738		dev_err(device, "Unable to set up channel sysfs files\n");
1739		return ret;
1740	}
1741
1742	kobject_uevent(kobj, KOBJ_ADD);
1743
1744	return 0;
1745}
1746
1747/*
1748 * vmbus_remove_channel_attr_group - remove the channel's attribute group
1749 */
1750void vmbus_remove_channel_attr_group(struct vmbus_channel *channel)
1751{
1752	sysfs_remove_group(&channel->kobj, &vmbus_chan_group);
1753}
1754
1755/*
1756 * vmbus_device_create - Creates and registers a new child device
1757 * on the vmbus.
1758 */
1759struct hv_device *vmbus_device_create(const guid_t *type,
1760				      const guid_t *instance,
1761				      struct vmbus_channel *channel)
1762{
1763	struct hv_device *child_device_obj;
1764
1765	child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
1766	if (!child_device_obj) {
1767		pr_err("Unable to allocate device object for child device\n");
1768		return NULL;
1769	}
1770
1771	child_device_obj->channel = channel;
1772	guid_copy(&child_device_obj->dev_type, type);
1773	guid_copy(&child_device_obj->dev_instance, instance);
1774	child_device_obj->vendor_id = 0x1414; /* MSFT vendor ID */
1775
1776	return child_device_obj;
1777}
1778
1779/*
1780 * vmbus_device_register - Register the child device
1781 */
1782int vmbus_device_register(struct hv_device *child_device_obj)
1783{
1784	struct kobject *kobj = &child_device_obj->device.kobj;
1785	int ret;
1786
1787	dev_set_name(&child_device_obj->device, "%pUl",
1788		     child_device_obj->channel->offermsg.offer.if_instance.b);
1789
1790	child_device_obj->device.bus = &hv_bus;
1791	child_device_obj->device.parent = &hv_acpi_dev->dev;
1792	child_device_obj->device.release = vmbus_device_release;
1793
1794	/*
1795	 * Register with the LDM. This will kick off the driver/device
1796	 * binding...which will eventually call vmbus_match() and vmbus_probe()
1797	 */
1798	ret = device_register(&child_device_obj->device);
1799	if (ret) {
1800		pr_err("Unable to register child device\n");
1801		return ret;
1802	}
1803
1804	child_device_obj->channels_kset = kset_create_and_add("channels",
1805							      NULL, kobj);
1806	if (!child_device_obj->channels_kset) {
1807		ret = -ENOMEM;
1808		goto err_dev_unregister;
1809	}
1810
1811	ret = vmbus_add_channel_kobj(child_device_obj,
1812				     child_device_obj->channel);
1813	if (ret) {
1814		pr_err("Unable to register primary channeln");
1815		goto err_kset_unregister;
1816	}
 
1817
1818	return 0;
1819
1820err_kset_unregister:
1821	kset_unregister(child_device_obj->channels_kset);
1822
1823err_dev_unregister:
1824	device_unregister(&child_device_obj->device);
1825	return ret;
1826}
1827
1828/*
1829 * vmbus_device_unregister - Remove the specified child device
1830 * from the vmbus.
1831 */
1832void vmbus_device_unregister(struct hv_device *device_obj)
1833{
1834	pr_debug("child device %s unregistered\n",
1835		dev_name(&device_obj->device));
1836
1837	kset_unregister(device_obj->channels_kset);
1838
1839	/*
1840	 * Kick off the process of unregistering the device.
1841	 * This will call vmbus_remove() and eventually vmbus_device_release()
1842	 */
1843	device_unregister(&device_obj->device);
1844}
1845
1846
1847/*
1848 * VMBUS is an acpi enumerated device. Get the information we
1849 * need from DSDT.
1850 */
1851#define VTPM_BASE_ADDRESS 0xfed40000
1852static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
1853{
1854	resource_size_t start = 0;
1855	resource_size_t end = 0;
1856	struct resource *new_res;
1857	struct resource **old_res = &hyperv_mmio;
1858	struct resource **prev_res = NULL;
1859
1860	switch (res->type) {
1861
1862	/*
1863	 * "Address" descriptors are for bus windows. Ignore
1864	 * "memory" descriptors, which are for registers on
1865	 * devices.
1866	 */
1867	case ACPI_RESOURCE_TYPE_ADDRESS32:
1868		start = res->data.address32.address.minimum;
1869		end = res->data.address32.address.maximum;
1870		break;
1871
1872	case ACPI_RESOURCE_TYPE_ADDRESS64:
1873		start = res->data.address64.address.minimum;
1874		end = res->data.address64.address.maximum;
1875		break;
1876
1877	default:
1878		/* Unused resource type */
1879		return AE_OK;
1880
1881	}
1882	/*
1883	 * Ignore ranges that are below 1MB, as they're not
1884	 * necessary or useful here.
1885	 */
1886	if (end < 0x100000)
1887		return AE_OK;
1888
1889	new_res = kzalloc(sizeof(*new_res), GFP_ATOMIC);
1890	if (!new_res)
1891		return AE_NO_MEMORY;
1892
1893	/* If this range overlaps the virtual TPM, truncate it. */
1894	if (end > VTPM_BASE_ADDRESS && start < VTPM_BASE_ADDRESS)
1895		end = VTPM_BASE_ADDRESS;
1896
1897	new_res->name = "hyperv mmio";
1898	new_res->flags = IORESOURCE_MEM;
1899	new_res->start = start;
1900	new_res->end = end;
1901
1902	/*
1903	 * If two ranges are adjacent, merge them.
1904	 */
1905	do {
1906		if (!*old_res) {
1907			*old_res = new_res;
1908			break;
1909		}
1910
1911		if (((*old_res)->end + 1) == new_res->start) {
1912			(*old_res)->end = new_res->end;
1913			kfree(new_res);
1914			break;
1915		}
1916
1917		if ((*old_res)->start == new_res->end + 1) {
1918			(*old_res)->start = new_res->start;
1919			kfree(new_res);
1920			break;
1921		}
1922
1923		if ((*old_res)->start > new_res->end) {
1924			new_res->sibling = *old_res;
1925			if (prev_res)
1926				(*prev_res)->sibling = new_res;
1927			*old_res = new_res;
1928			break;
1929		}
1930
1931		prev_res = old_res;
1932		old_res = &(*old_res)->sibling;
1933
1934	} while (1);
1935
1936	return AE_OK;
1937}
1938
1939static int vmbus_acpi_remove(struct acpi_device *device)
1940{
1941	struct resource *cur_res;
1942	struct resource *next_res;
1943
1944	if (hyperv_mmio) {
1945		if (fb_mmio) {
1946			__release_region(hyperv_mmio, fb_mmio->start,
1947					 resource_size(fb_mmio));
1948			fb_mmio = NULL;
1949		}
1950
1951		for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
1952			next_res = cur_res->sibling;
1953			kfree(cur_res);
1954		}
1955	}
1956
1957	return 0;
1958}
1959
1960static void vmbus_reserve_fb(void)
1961{
1962	int size;
1963	/*
1964	 * Make a claim for the frame buffer in the resource tree under the
1965	 * first node, which will be the one below 4GB.  The length seems to
1966	 * be underreported, particularly in a Generation 1 VM.  So start out
1967	 * reserving a larger area and make it smaller until it succeeds.
1968	 */
1969
1970	if (screen_info.lfb_base) {
1971		if (efi_enabled(EFI_BOOT))
1972			size = max_t(__u32, screen_info.lfb_size, 0x800000);
1973		else
1974			size = max_t(__u32, screen_info.lfb_size, 0x4000000);
1975
1976		for (; !fb_mmio && (size >= 0x100000); size >>= 1) {
1977			fb_mmio = __request_region(hyperv_mmio,
1978						   screen_info.lfb_base, size,
1979						   fb_mmio_name, 0);
1980		}
1981	}
1982}
1983
1984/**
1985 * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
1986 * @new:		If successful, supplied a pointer to the
1987 *			allocated MMIO space.
1988 * @device_obj:		Identifies the caller
1989 * @min:		Minimum guest physical address of the
1990 *			allocation
1991 * @max:		Maximum guest physical address
1992 * @size:		Size of the range to be allocated
1993 * @align:		Alignment of the range to be allocated
1994 * @fb_overlap_ok:	Whether this allocation can be allowed
1995 *			to overlap the video frame buffer.
1996 *
1997 * This function walks the resources granted to VMBus by the
1998 * _CRS object in the ACPI namespace underneath the parent
1999 * "bridge" whether that's a root PCI bus in the Generation 1
2000 * case or a Module Device in the Generation 2 case.  It then
2001 * attempts to allocate from the global MMIO pool in a way that
2002 * matches the constraints supplied in these parameters and by
2003 * that _CRS.
2004 *
2005 * Return: 0 on success, -errno on failure
2006 */
2007int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
2008			resource_size_t min, resource_size_t max,
2009			resource_size_t size, resource_size_t align,
2010			bool fb_overlap_ok)
2011{
2012	struct resource *iter, *shadow;
2013	resource_size_t range_min, range_max, start;
2014	const char *dev_n = dev_name(&device_obj->device);
2015	int retval;
2016
2017	retval = -ENXIO;
2018	down(&hyperv_mmio_lock);
2019
2020	/*
2021	 * If overlaps with frame buffers are allowed, then first attempt to
2022	 * make the allocation from within the reserved region.  Because it
2023	 * is already reserved, no shadow allocation is necessary.
2024	 */
2025	if (fb_overlap_ok && fb_mmio && !(min > fb_mmio->end) &&
2026	    !(max < fb_mmio->start)) {
2027
2028		range_min = fb_mmio->start;
2029		range_max = fb_mmio->end;
2030		start = (range_min + align - 1) & ~(align - 1);
2031		for (; start + size - 1 <= range_max; start += align) {
2032			*new = request_mem_region_exclusive(start, size, dev_n);
2033			if (*new) {
2034				retval = 0;
2035				goto exit;
2036			}
2037		}
2038	}
2039
2040	for (iter = hyperv_mmio; iter; iter = iter->sibling) {
2041		if ((iter->start >= max) || (iter->end <= min))
2042			continue;
2043
2044		range_min = iter->start;
2045		range_max = iter->end;
2046		start = (range_min + align - 1) & ~(align - 1);
2047		for (; start + size - 1 <= range_max; start += align) {
2048			shadow = __request_region(iter, start, size, NULL,
2049						  IORESOURCE_BUSY);
2050			if (!shadow)
2051				continue;
2052
2053			*new = request_mem_region_exclusive(start, size, dev_n);
2054			if (*new) {
2055				shadow->name = (char *)*new;
2056				retval = 0;
2057				goto exit;
2058			}
2059
2060			__release_region(iter, start, size);
2061		}
2062	}
2063
2064exit:
2065	up(&hyperv_mmio_lock);
2066	return retval;
2067}
2068EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
2069
2070/**
2071 * vmbus_free_mmio() - Free a memory-mapped I/O range.
2072 * @start:		Base address of region to release.
2073 * @size:		Size of the range to be allocated
2074 *
2075 * This function releases anything requested by
2076 * vmbus_mmio_allocate().
2077 */
2078void vmbus_free_mmio(resource_size_t start, resource_size_t size)
2079{
2080	struct resource *iter;
2081
2082	down(&hyperv_mmio_lock);
2083	for (iter = hyperv_mmio; iter; iter = iter->sibling) {
2084		if ((iter->start >= start + size) || (iter->end <= start))
2085			continue;
2086
2087		__release_region(iter, start, size);
2088	}
2089	release_mem_region(start, size);
2090	up(&hyperv_mmio_lock);
2091
2092}
2093EXPORT_SYMBOL_GPL(vmbus_free_mmio);
2094
2095static int vmbus_acpi_add(struct acpi_device *device)
2096{
2097	acpi_status result;
2098	int ret_val = -ENODEV;
2099	struct acpi_device *ancestor;
2100
2101	hv_acpi_dev = device;
2102
2103	result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
2104					vmbus_walk_resources, NULL);
2105
2106	if (ACPI_FAILURE(result))
2107		goto acpi_walk_err;
2108	/*
2109	 * Some ancestor of the vmbus acpi device (Gen1 or Gen2
2110	 * firmware) is the VMOD that has the mmio ranges. Get that.
2111	 */
2112	for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
2113		result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
2114					     vmbus_walk_resources, NULL);
2115
2116		if (ACPI_FAILURE(result))
2117			continue;
2118		if (hyperv_mmio) {
2119			vmbus_reserve_fb();
2120			break;
2121		}
2122	}
2123	ret_val = 0;
2124
2125acpi_walk_err:
2126	complete(&probe_event);
2127	if (ret_val)
2128		vmbus_acpi_remove(device);
2129	return ret_val;
2130}
2131
2132#ifdef CONFIG_PM_SLEEP
2133static int vmbus_bus_suspend(struct device *dev)
2134{
2135	struct vmbus_channel *channel, *sc;
2136	unsigned long flags;
2137
2138	while (atomic_read(&vmbus_connection.offer_in_progress) != 0) {
2139		/*
2140		 * We wait here until the completion of any channel
2141		 * offers that are currently in progress.
2142		 */
2143		msleep(1);
2144	}
2145
2146	mutex_lock(&vmbus_connection.channel_mutex);
2147	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
2148		if (!is_hvsock_channel(channel))
2149			continue;
2150
2151		vmbus_force_channel_rescinded(channel);
2152	}
2153	mutex_unlock(&vmbus_connection.channel_mutex);
2154
2155	/*
2156	 * Wait until all the sub-channels and hv_sock channels have been
2157	 * cleaned up. Sub-channels should be destroyed upon suspend, otherwise
2158	 * they would conflict with the new sub-channels that will be created
2159	 * in the resume path. hv_sock channels should also be destroyed, but
2160	 * a hv_sock channel of an established hv_sock connection can not be
2161	 * really destroyed since it may still be referenced by the userspace
2162	 * application, so we just force the hv_sock channel to be rescinded
2163	 * by vmbus_force_channel_rescinded(), and the userspace application
2164	 * will thoroughly destroy the channel after hibernation.
2165	 *
2166	 * Note: the counter nr_chan_close_on_suspend may never go above 0 if
2167	 * the VM has no sub-channel and hv_sock channel, e.g. a 1-vCPU VM.
2168	 */
2169	if (atomic_read(&vmbus_connection.nr_chan_close_on_suspend) > 0)
2170		wait_for_completion(&vmbus_connection.ready_for_suspend_event);
2171
2172	WARN_ON(atomic_read(&vmbus_connection.nr_chan_fixup_on_resume) != 0);
 
 
 
2173
2174	mutex_lock(&vmbus_connection.channel_mutex);
2175
2176	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
2177		/*
2178		 * Invalidate the field. Upon resume, vmbus_onoffer() will fix
2179		 * up the field, and the other fields (if necessary).
 
 
2180		 */
 
2181		channel->offermsg.child_relid = INVALID_RELID;
2182
2183		if (is_hvsock_channel(channel)) {
2184			if (!channel->rescind) {
2185				pr_err("hv_sock channel not rescinded!\n");
2186				WARN_ON_ONCE(1);
2187			}
2188			continue;
2189		}
2190
2191		spin_lock_irqsave(&channel->lock, flags);
2192		list_for_each_entry(sc, &channel->sc_list, sc_list) {
2193			pr_err("Sub-channel not deleted!\n");
2194			WARN_ON_ONCE(1);
2195		}
2196		spin_unlock_irqrestore(&channel->lock, flags);
2197
2198		atomic_inc(&vmbus_connection.nr_chan_fixup_on_resume);
2199	}
2200
2201	mutex_unlock(&vmbus_connection.channel_mutex);
2202
2203	vmbus_initiate_unload(false);
2204
2205	vmbus_connection.conn_state = DISCONNECTED;
2206
2207	/* Reset the event for the next resume. */
2208	reinit_completion(&vmbus_connection.ready_for_resume_event);
2209
2210	return 0;
2211}
2212
2213static int vmbus_bus_resume(struct device *dev)
2214{
2215	struct vmbus_channel_msginfo *msginfo;
2216	size_t msgsize;
2217	int ret;
2218
2219	/*
2220	 * We only use the 'vmbus_proto_version', which was in use before
2221	 * hibernation, to re-negotiate with the host.
2222	 */
2223	if (vmbus_proto_version == VERSION_INVAL ||
2224	    vmbus_proto_version == 0) {
2225		pr_err("Invalid proto version = 0x%x\n", vmbus_proto_version);
2226		return -EINVAL;
2227	}
2228
2229	msgsize = sizeof(*msginfo) +
2230		  sizeof(struct vmbus_channel_initiate_contact);
2231
2232	msginfo = kzalloc(msgsize, GFP_KERNEL);
2233
2234	if (msginfo == NULL)
2235		return -ENOMEM;
2236
2237	ret = vmbus_negotiate_version(msginfo, vmbus_proto_version);
2238
2239	kfree(msginfo);
2240
2241	if (ret != 0)
2242		return ret;
2243
2244	WARN_ON(atomic_read(&vmbus_connection.nr_chan_fixup_on_resume) == 0);
2245
2246	vmbus_request_offers();
2247
2248	wait_for_completion(&vmbus_connection.ready_for_resume_event);
 
 
2249
2250	/* Reset the event for the next suspend. */
2251	reinit_completion(&vmbus_connection.ready_for_suspend_event);
2252
2253	return 0;
2254}
 
 
 
2255#endif /* CONFIG_PM_SLEEP */
2256
2257static const struct acpi_device_id vmbus_acpi_device_ids[] = {
2258	{"VMBUS", 0},
2259	{"VMBus", 0},
2260	{"", 0},
2261};
2262MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids);
2263
2264/*
2265 * Note: we must use SET_NOIRQ_SYSTEM_SLEEP_PM_OPS rather than
2266 * SET_SYSTEM_SLEEP_PM_OPS, otherwise NIC SR-IOV can not work, because the
2267 * "pci_dev_pm_ops" uses the "noirq" callbacks: in the resume path, the
2268 * pci "noirq" restore callback runs before "non-noirq" callbacks (see
2269 * resume_target_kernel() -> dpm_resume_start(), and hibernation_restore() ->
2270 * dpm_resume_end()). This means vmbus_bus_resume() and the pci-hyperv's
2271 * resume callback must also run via the "noirq" callbacks.
 
 
 
2272 */
 
2273static const struct dev_pm_ops vmbus_bus_pm = {
2274	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(vmbus_bus_suspend, vmbus_bus_resume)
 
 
 
 
 
2275};
2276
2277static struct acpi_driver vmbus_acpi_driver = {
2278	.name = "vmbus",
2279	.ids = vmbus_acpi_device_ids,
2280	.ops = {
2281		.add = vmbus_acpi_add,
2282		.remove = vmbus_acpi_remove,
2283	},
2284	.drv.pm = &vmbus_bus_pm,
2285};
2286
2287static void hv_kexec_handler(void)
2288{
2289	hv_stimer_global_cleanup();
2290	vmbus_initiate_unload(false);
2291	vmbus_connection.conn_state = DISCONNECTED;
2292	/* Make sure conn_state is set as hv_synic_cleanup checks for it */
2293	mb();
2294	cpuhp_remove_state(hyperv_cpuhp_online);
2295	hyperv_cleanup();
2296};
2297
2298static void hv_crash_handler(struct pt_regs *regs)
2299{
2300	int cpu;
2301
2302	vmbus_initiate_unload(true);
2303	/*
2304	 * In crash handler we can't schedule synic cleanup for all CPUs,
2305	 * doing the cleanup for current CPU only. This should be sufficient
2306	 * for kdump.
2307	 */
2308	vmbus_connection.conn_state = DISCONNECTED;
2309	cpu = smp_processor_id();
2310	hv_stimer_cleanup(cpu);
2311	hv_synic_cleanup(cpu);
2312	hyperv_cleanup();
2313};
2314
2315static int hv_synic_suspend(void)
2316{
2317	/*
2318	 * When we reach here, all the non-boot CPUs have been offlined, and
2319	 * the stimers on them have been unbound in hv_synic_cleanup() ->
 
 
2320	 * hv_stimer_cleanup() -> clockevents_unbind_device().
2321	 *
2322	 * hv_synic_suspend() only runs on CPU0 with interrupts disabled. Here
2323	 * we do not unbind the stimer on CPU0 because: 1) it's unnecessary
2324	 * because the interrupts remain disabled between syscore_suspend()
2325	 * and syscore_resume(): see create_image() and resume_target_kernel();
 
2326	 * 2) the stimer on CPU0 is automatically disabled later by
2327	 * syscore_suspend() -> timekeeping_suspend() -> tick_suspend() -> ...
2328	 * -> clockevents_shutdown() -> ... -> hv_ce_shutdown(); 3) a warning
2329	 * would be triggered if we call clockevents_unbind_device(), which
2330	 * may sleep, in an interrupts-disabled context. So, we intentionally
2331	 * don't call hv_stimer_cleanup(0) here.
2332	 */
2333
2334	hv_synic_disable_regs(0);
2335
2336	return 0;
2337}
2338
2339static void hv_synic_resume(void)
2340{
2341	hv_synic_enable_regs(0);
2342
2343	/*
2344	 * Note: we don't need to call hv_stimer_init(0), because the timer
2345	 * on CPU0 is not unbound in hv_synic_suspend(), and the timer is
2346	 * automatically re-enabled in timekeeping_resume().
2347	 */
2348}
2349
2350/* The callbacks run only on CPU0, with irqs_disabled. */
2351static struct syscore_ops hv_synic_syscore_ops = {
2352	.suspend = hv_synic_suspend,
2353	.resume = hv_synic_resume,
2354};
2355
2356static int __init hv_acpi_init(void)
2357{
2358	int ret, t;
2359
2360	if (!hv_is_hyperv_initialized())
2361		return -ENODEV;
2362
2363	init_completion(&probe_event);
2364
2365	/*
2366	 * Get ACPI resources first.
2367	 */
2368	ret = acpi_bus_register_driver(&vmbus_acpi_driver);
2369
2370	if (ret)
2371		return ret;
2372
2373	t = wait_for_completion_timeout(&probe_event, 5*HZ);
2374	if (t == 0) {
2375		ret = -ETIMEDOUT;
2376		goto cleanup;
2377	}
 
2378
2379	ret = vmbus_bus_init();
2380	if (ret)
2381		goto cleanup;
2382
2383	hv_setup_kexec_handler(hv_kexec_handler);
2384	hv_setup_crash_handler(hv_crash_handler);
2385
2386	register_syscore_ops(&hv_synic_syscore_ops);
2387
2388	return 0;
2389
2390cleanup:
2391	acpi_bus_unregister_driver(&vmbus_acpi_driver);
2392	hv_acpi_dev = NULL;
2393	return ret;
2394}
2395
2396static void __exit vmbus_exit(void)
2397{
2398	int cpu;
2399
2400	unregister_syscore_ops(&hv_synic_syscore_ops);
2401
2402	hv_remove_kexec_handler();
2403	hv_remove_crash_handler();
2404	vmbus_connection.conn_state = DISCONNECTED;
2405	hv_stimer_global_cleanup();
2406	vmbus_disconnect();
2407	hv_remove_vmbus_irq();
2408	for_each_online_cpu(cpu) {
2409		struct hv_per_cpu_context *hv_cpu
2410			= per_cpu_ptr(hv_context.cpu_context, cpu);
2411
2412		tasklet_kill(&hv_cpu->msg_dpc);
2413	}
 
 
2414	vmbus_free_channels();
 
2415
2416	if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
2417		kmsg_dump_unregister(&hv_kmsg_dumper);
2418		unregister_die_notifier(&hyperv_die_block);
2419		atomic_notifier_chain_unregister(&panic_notifier_list,
2420						 &hyperv_panic_block);
2421	}
2422
2423	free_page((unsigned long)hv_panic_page);
2424	unregister_sysctl_table(hv_ctl_table_hdr);
2425	hv_ctl_table_hdr = NULL;
2426	bus_unregister(&hv_bus);
2427
2428	cpuhp_remove_state(hyperv_cpuhp_online);
2429	hv_synic_free();
2430	acpi_bus_unregister_driver(&vmbus_acpi_driver);
2431}
2432
2433
2434MODULE_LICENSE("GPL");
2435MODULE_DESCRIPTION("Microsoft Hyper-V VMBus Driver");
2436
2437subsys_initcall(hv_acpi_init);
2438module_exit(vmbus_exit);