Linux Audio

Check our new training course

Loading...
v4.6
 
   1/*
   2 * Kernel-based Virtual Machine driver for Linux
   3 *
   4 * This module enables machines with Intel VT-x extensions to run virtual
   5 * machines without emulation or binary translation.
   6 *
   7 * Copyright (C) 2006 Qumranet, Inc.
   8 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
   9 *
  10 * Authors:
  11 *   Avi Kivity   <avi@qumranet.com>
  12 *   Yaniv Kamay  <yaniv@qumranet.com>
  13 *
  14 * This work is licensed under the terms of the GNU GPL, version 2.  See
  15 * the COPYING file in the top-level directory.
  16 *
  17 */
  18
  19#include <kvm/iodev.h>
  20
  21#include <linux/kvm_host.h>
  22#include <linux/kvm.h>
  23#include <linux/module.h>
  24#include <linux/errno.h>
  25#include <linux/percpu.h>
  26#include <linux/mm.h>
  27#include <linux/miscdevice.h>
  28#include <linux/vmalloc.h>
  29#include <linux/reboot.h>
  30#include <linux/debugfs.h>
  31#include <linux/highmem.h>
  32#include <linux/file.h>
  33#include <linux/syscore_ops.h>
  34#include <linux/cpu.h>
  35#include <linux/sched.h>
 
 
  36#include <linux/cpumask.h>
  37#include <linux/smp.h>
  38#include <linux/anon_inodes.h>
  39#include <linux/profile.h>
  40#include <linux/kvm_para.h>
  41#include <linux/pagemap.h>
  42#include <linux/mman.h>
  43#include <linux/swap.h>
  44#include <linux/bitops.h>
  45#include <linux/spinlock.h>
  46#include <linux/compat.h>
  47#include <linux/srcu.h>
  48#include <linux/hugetlb.h>
  49#include <linux/slab.h>
  50#include <linux/sort.h>
  51#include <linux/bsearch.h>
 
 
 
 
  52
  53#include <asm/processor.h>
  54#include <asm/io.h>
  55#include <asm/ioctl.h>
  56#include <asm/uaccess.h>
  57#include <asm/pgtable.h>
  58
  59#include "coalesced_mmio.h"
  60#include "async_pf.h"
 
  61#include "vfio.h"
  62
  63#define CREATE_TRACE_POINTS
  64#include <trace/events/kvm.h>
  65
 
 
 
 
 
  66MODULE_AUTHOR("Qumranet");
  67MODULE_LICENSE("GPL");
  68
  69/* Architectures should define their poll value according to the halt latency */
  70static unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
  71module_param(halt_poll_ns, uint, S_IRUGO | S_IWUSR);
 
  72
  73/* Default doubles per-vcpu halt_poll_ns. */
  74static unsigned int halt_poll_ns_grow = 2;
  75module_param(halt_poll_ns_grow, uint, S_IRUGO | S_IWUSR);
 
 
 
 
 
 
  76
  77/* Default resets per-vcpu halt_poll_ns . */
  78static unsigned int halt_poll_ns_shrink;
  79module_param(halt_poll_ns_shrink, uint, S_IRUGO | S_IWUSR);
 
  80
  81/*
  82 * Ordering of locks:
  83 *
  84 *	kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  85 */
  86
  87DEFINE_SPINLOCK(kvm_lock);
  88static DEFINE_RAW_SPINLOCK(kvm_count_lock);
  89LIST_HEAD(vm_list);
  90
  91static cpumask_var_t cpus_hardware_enabled;
  92static int kvm_usage_count;
  93static atomic_t hardware_enable_failed;
  94
  95struct kmem_cache *kvm_vcpu_cache;
  96EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  97
  98static __read_mostly struct preempt_ops kvm_preempt_ops;
 
  99
 100struct dentry *kvm_debugfs_dir;
 101EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
 102
 
 
 103static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
 104			   unsigned long arg);
 105#ifdef CONFIG_KVM_COMPAT
 106static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
 107				  unsigned long arg);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 108#endif
 109static int hardware_enable_all(void);
 110static void hardware_disable_all(void);
 111
 112static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
 113
 114static void kvm_release_pfn_dirty(kvm_pfn_t pfn);
 115static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
 116
 117__visible bool kvm_rebooting;
 118EXPORT_SYMBOL_GPL(kvm_rebooting);
 119
 120static bool largepages_enabled = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 121
 122bool kvm_is_reserved_pfn(kvm_pfn_t pfn)
 123{
 
 
 
 
 
 124	if (pfn_valid(pfn))
 125		return PageReserved(pfn_to_page(pfn));
 
 
 126
 127	return true;
 128}
 129
 
 
 
 
 
 
 
 
 
 
 130/*
 131 * Switches to specified vcpu, until a matching vcpu_put()
 132 */
 133int vcpu_load(struct kvm_vcpu *vcpu)
 134{
 135	int cpu;
 136
 137	if (mutex_lock_killable(&vcpu->mutex))
 138		return -EINTR;
 139	cpu = get_cpu();
 140	preempt_notifier_register(&vcpu->preempt_notifier);
 141	kvm_arch_vcpu_load(vcpu, cpu);
 142	put_cpu();
 143	return 0;
 144}
 
 145
 146void vcpu_put(struct kvm_vcpu *vcpu)
 147{
 148	preempt_disable();
 149	kvm_arch_vcpu_put(vcpu);
 150	preempt_notifier_unregister(&vcpu->preempt_notifier);
 
 151	preempt_enable();
 152	mutex_unlock(&vcpu->mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 153}
 154
 155static void ack_flush(void *_completed)
 156{
 157}
 158
 159bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 160{
 161	int i, cpu, me;
 162	cpumask_var_t cpus;
 163	bool called = true;
 164	struct kvm_vcpu *vcpu;
 165
 166	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 167
 168	me = get_cpu();
 
 169	kvm_for_each_vcpu(i, vcpu, kvm) {
 
 
 
 
 170		kvm_make_request(req, vcpu);
 171		cpu = vcpu->cpu;
 172
 173		/* Set ->requests bit before we read ->mode. */
 174		smp_mb__after_atomic();
 175
 176		if (cpus != NULL && cpu != -1 && cpu != me &&
 177		      kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
 178			cpumask_set_cpu(cpu, cpus);
 179	}
 180	if (unlikely(cpus == NULL))
 181		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 182	else if (!cpumask_empty(cpus))
 183		smp_call_function_many(cpus, ack_flush, NULL, 1);
 184	else
 185		called = false;
 186	put_cpu();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 187	free_cpumask_var(cpus);
 188	return called;
 189}
 190
 
 
 
 
 
 
 191#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
 192void kvm_flush_remote_tlbs(struct kvm *kvm)
 193{
 194	/*
 195	 * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
 196	 * kvm_make_all_cpus_request.
 197	 */
 198	long dirty_count = smp_load_acquire(&kvm->tlbs_dirty);
 199
 200	/*
 201	 * We want to publish modifications to the page tables before reading
 202	 * mode. Pairs with a memory barrier in arch-specific code.
 203	 * - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
 204	 * and smp_mb in walk_shadow_page_lockless_begin/end.
 205	 * - powerpc: smp_mb in kvmppc_prepare_to_enter.
 206	 *
 207	 * There is already an smp_mb__after_atomic() before
 208	 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
 209	 * barrier here.
 210	 */
 211	if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 212		++kvm->stat.remote_tlb_flush;
 
 213	cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 214}
 215EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 216#endif
 217
 218void kvm_reload_remote_mmus(struct kvm *kvm)
 219{
 220	kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 221}
 222
 223int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 
 
 224{
 225	struct page *page;
 226	int r;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 227
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 228	mutex_init(&vcpu->mutex);
 229	vcpu->cpu = -1;
 230	vcpu->kvm = kvm;
 231	vcpu->vcpu_id = id;
 232	vcpu->pid = NULL;
 233	init_swait_queue_head(&vcpu->wq);
 234	kvm_async_pf_vcpu_init(vcpu);
 235
 236	vcpu->pre_pcpu = -1;
 237	INIT_LIST_HEAD(&vcpu->blocked_vcpu_list);
 238
 239	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 240	if (!page) {
 241		r = -ENOMEM;
 242		goto fail;
 243	}
 244	vcpu->run = page_address(page);
 245
 246	kvm_vcpu_set_in_spin_loop(vcpu, false);
 247	kvm_vcpu_set_dy_eligible(vcpu, false);
 248	vcpu->preempted = false;
 249
 250	r = kvm_arch_vcpu_init(vcpu);
 251	if (r < 0)
 252		goto fail_free_run;
 253	return 0;
 254
 255fail_free_run:
 256	free_page((unsigned long)vcpu->run);
 257fail:
 258	return r;
 259}
 260EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 261
 262void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 263{
 264	put_pid(vcpu->pid);
 265	kvm_arch_vcpu_uninit(vcpu);
 
 
 
 
 
 
 
 
 266	free_page((unsigned long)vcpu->run);
 
 267}
 268EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 269
 270#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 271static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 272{
 273	return container_of(mn, struct kvm, mmu_notifier);
 274}
 275
 276static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 277					     struct mm_struct *mm,
 278					     unsigned long address)
 279{
 280	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 281	int need_tlb_flush, idx;
 282
 283	/*
 284	 * When ->invalidate_page runs, the linux pte has been zapped
 285	 * already but the page is still allocated until
 286	 * ->invalidate_page returns. So if we increase the sequence
 287	 * here the kvm page fault will notice if the spte can't be
 288	 * established because the page is going to be freed. If
 289	 * instead the kvm page fault establishes the spte before
 290	 * ->invalidate_page runs, kvm_unmap_hva will release it
 291	 * before returning.
 292	 *
 293	 * The sequence increase only need to be seen at spin_unlock
 294	 * time, and not at spin_lock time.
 295	 *
 296	 * Increasing the sequence after the spin_unlock would be
 297	 * unsafe because the kvm page fault could then establish the
 298	 * pte after kvm_unmap_hva returned, without noticing the page
 299	 * is going to be freed.
 300	 */
 301	idx = srcu_read_lock(&kvm->srcu);
 302	spin_lock(&kvm->mmu_lock);
 
 
 303
 304	kvm->mmu_notifier_seq++;
 305	need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
 306	/* we've to flush the tlb before the pages can be freed */
 307	if (need_tlb_flush)
 308		kvm_flush_remote_tlbs(kvm);
 
 
 
 
 
 
 
 
 
 309
 310	spin_unlock(&kvm->mmu_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 311
 312	kvm_arch_mmu_notifier_invalidate_page(kvm, address);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 313
 314	srcu_read_unlock(&kvm->srcu, idx);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 315}
 316
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 317static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 318					struct mm_struct *mm,
 319					unsigned long address,
 320					pte_t pte)
 321{
 322	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 323	int idx;
 324
 325	idx = srcu_read_lock(&kvm->srcu);
 326	spin_lock(&kvm->mmu_lock);
 327	kvm->mmu_notifier_seq++;
 328	kvm_set_spte_hva(kvm, address, pte);
 329	spin_unlock(&kvm->mmu_lock);
 330	srcu_read_unlock(&kvm->srcu, idx);
 
 
 
 
 331}
 332
 333static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 334						    struct mm_struct *mm,
 335						    unsigned long start,
 336						    unsigned long end)
 337{
 338	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 339	int need_tlb_flush = 0, idx;
 340
 341	idx = srcu_read_lock(&kvm->srcu);
 342	spin_lock(&kvm->mmu_lock);
 343	/*
 344	 * The count increase must become visible at unlock time as no
 345	 * spte can be established without taking the mmu_lock and
 346	 * count is also read inside the mmu_lock critical section.
 347	 */
 348	kvm->mmu_notifier_count++;
 349	need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
 350	need_tlb_flush |= kvm->tlbs_dirty;
 351	/* we've to flush the tlb before the pages can be freed */
 352	if (need_tlb_flush)
 353		kvm_flush_remote_tlbs(kvm);
 354
 355	spin_unlock(&kvm->mmu_lock);
 356	srcu_read_unlock(&kvm->srcu, idx);
 
 
 
 
 
 
 
 
 
 
 357}
 358
 359static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 360						  struct mm_struct *mm,
 361						  unsigned long start,
 362						  unsigned long end)
 363{
 364	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 365
 366	spin_lock(&kvm->mmu_lock);
 
 
 367	/*
 368	 * This sequence increase will notify the kvm page fault that
 369	 * the page that is going to be mapped in the spte could have
 370	 * been freed.
 371	 */
 372	kvm->mmu_notifier_seq++;
 373	smp_wmb();
 374	/*
 375	 * The above sequence increase must be visible before the
 376	 * below count decrease, which is ensured by the smp_wmb above
 377	 * in conjunction with the smp_rmb in mmu_notifier_retry().
 378	 */
 379	kvm->mmu_notifier_count--;
 380	spin_unlock(&kvm->mmu_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 381
 382	BUG_ON(kvm->mmu_notifier_count < 0);
 383}
 384
 385static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 386					      struct mm_struct *mm,
 387					      unsigned long start,
 388					      unsigned long end)
 389{
 390	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 391	int young, idx;
 392
 393	idx = srcu_read_lock(&kvm->srcu);
 394	spin_lock(&kvm->mmu_lock);
 395
 396	young = kvm_age_hva(kvm, start, end);
 397	if (young)
 398		kvm_flush_remote_tlbs(kvm);
 399
 400	spin_unlock(&kvm->mmu_lock);
 401	srcu_read_unlock(&kvm->srcu, idx);
 402
 403	return young;
 404}
 405
 406static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
 407					struct mm_struct *mm,
 408					unsigned long start,
 409					unsigned long end)
 410{
 411	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 412	int young, idx;
 413
 414	idx = srcu_read_lock(&kvm->srcu);
 415	spin_lock(&kvm->mmu_lock);
 416	/*
 417	 * Even though we do not flush TLB, this will still adversely
 418	 * affect performance on pre-Haswell Intel EPT, where there is
 419	 * no EPT Access Bit to clear so that we have to tear down EPT
 420	 * tables instead. If we find this unacceptable, we can always
 421	 * add a parameter to kvm_age_hva so that it effectively doesn't
 422	 * do anything on clear_young.
 423	 *
 424	 * Also note that currently we never issue secondary TLB flushes
 425	 * from clear_young, leaving this job up to the regular system
 426	 * cadence. If we find this inaccurate, we might come up with a
 427	 * more sophisticated heuristic later.
 428	 */
 429	young = kvm_age_hva(kvm, start, end);
 430	spin_unlock(&kvm->mmu_lock);
 431	srcu_read_unlock(&kvm->srcu, idx);
 432
 433	return young;
 434}
 435
 436static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 437				       struct mm_struct *mm,
 438				       unsigned long address)
 439{
 440	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 441	int young, idx;
 442
 443	idx = srcu_read_lock(&kvm->srcu);
 444	spin_lock(&kvm->mmu_lock);
 445	young = kvm_test_age_hva(kvm, address);
 446	spin_unlock(&kvm->mmu_lock);
 447	srcu_read_unlock(&kvm->srcu, idx);
 448
 449	return young;
 450}
 451
 452static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 453				     struct mm_struct *mm)
 454{
 455	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 456	int idx;
 457
 458	idx = srcu_read_lock(&kvm->srcu);
 459	kvm_arch_flush_shadow_all(kvm);
 460	srcu_read_unlock(&kvm->srcu, idx);
 461}
 462
 463static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 464	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
 465	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
 466	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
 467	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
 468	.clear_young		= kvm_mmu_notifier_clear_young,
 469	.test_young		= kvm_mmu_notifier_test_young,
 470	.change_pte		= kvm_mmu_notifier_change_pte,
 471	.release		= kvm_mmu_notifier_release,
 472};
 473
 474static int kvm_init_mmu_notifier(struct kvm *kvm)
 475{
 476	kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 477	return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 478}
 479
 480#else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 481
 482static int kvm_init_mmu_notifier(struct kvm *kvm)
 483{
 484	return 0;
 485}
 486
 487#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 488
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 489static struct kvm_memslots *kvm_alloc_memslots(void)
 490{
 491	int i;
 492	struct kvm_memslots *slots;
 493
 494	slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
 495	if (!slots)
 496		return NULL;
 497
 498	/*
 499	 * Init kvm generation close to the maximum to easily test the
 500	 * code of handling generation number wrap-around.
 501	 */
 502	slots->generation = -150;
 503	for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 504		slots->id_to_index[i] = slots->memslots[i].id = i;
 505
 506	return slots;
 507}
 508
 509static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 510{
 511	if (!memslot->dirty_bitmap)
 512		return;
 513
 514	kvfree(memslot->dirty_bitmap);
 515	memslot->dirty_bitmap = NULL;
 516}
 517
 518/*
 519 * Free any memory in @free but not in @dont.
 520 */
 521static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
 522			      struct kvm_memory_slot *dont)
 523{
 524	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 525		kvm_destroy_dirty_bitmap(free);
 526
 527	kvm_arch_free_memslot(kvm, free, dont);
 528
 529	free->npages = 0;
 
 530}
 531
 532static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
 533{
 534	struct kvm_memory_slot *memslot;
 535
 536	if (!slots)
 537		return;
 538
 539	kvm_for_each_memslot(memslot, slots)
 540		kvm_free_memslot(kvm, memslot, NULL);
 541
 542	kvfree(slots);
 543}
 544
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 545static struct kvm *kvm_create_vm(unsigned long type)
 546{
 547	int r, i;
 548	struct kvm *kvm = kvm_arch_alloc_vm();
 
 
 549
 550	if (!kvm)
 551		return ERR_PTR(-ENOMEM);
 552
 553	spin_lock_init(&kvm->mmu_lock);
 554	atomic_inc(&current->mm->mm_count);
 555	kvm->mm = current->mm;
 556	kvm_eventfd_init(kvm);
 557	mutex_init(&kvm->lock);
 558	mutex_init(&kvm->irq_lock);
 559	mutex_init(&kvm->slots_lock);
 560	atomic_set(&kvm->users_count, 1);
 561	INIT_LIST_HEAD(&kvm->devices);
 562
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 563	r = kvm_arch_init_vm(kvm, type);
 564	if (r)
 565		goto out_err_no_disable;
 566
 567	r = hardware_enable_all();
 568	if (r)
 569		goto out_err_no_disable;
 570
 571#ifdef CONFIG_HAVE_KVM_IRQFD
 572	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 573#endif
 574
 575	BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
 576
 577	r = -ENOMEM;
 578	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
 579		kvm->memslots[i] = kvm_alloc_memslots();
 580		if (!kvm->memslots[i])
 581			goto out_err_no_srcu;
 582	}
 583
 584	if (init_srcu_struct(&kvm->srcu))
 585		goto out_err_no_srcu;
 586	if (init_srcu_struct(&kvm->irq_srcu))
 587		goto out_err_no_irq_srcu;
 588	for (i = 0; i < KVM_NR_BUSES; i++) {
 589		kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
 590					GFP_KERNEL);
 591		if (!kvm->buses[i])
 592			goto out_err;
 593	}
 594
 595	r = kvm_init_mmu_notifier(kvm);
 596	if (r)
 
 
 
 
 597		goto out_err;
 598
 599	spin_lock(&kvm_lock);
 600	list_add(&kvm->vm_list, &vm_list);
 601	spin_unlock(&kvm_lock);
 602
 603	preempt_notifier_inc();
 
 604
 605	return kvm;
 606
 607out_err:
 608	cleanup_srcu_struct(&kvm->irq_srcu);
 609out_err_no_irq_srcu:
 610	cleanup_srcu_struct(&kvm->srcu);
 611out_err_no_srcu:
 
 612	hardware_disable_all();
 613out_err_no_disable:
 
 
 
 614	for (i = 0; i < KVM_NR_BUSES; i++)
 615		kfree(kvm->buses[i]);
 616	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
 617		kvm_free_memslots(kvm, kvm->memslots[i]);
 
 
 
 
 618	kvm_arch_free_vm(kvm);
 619	mmdrop(current->mm);
 620	return ERR_PTR(r);
 621}
 622
 623/*
 624 * Avoid using vmalloc for a small buffer.
 625 * Should not be used when the size is statically known.
 626 */
 627void *kvm_kvzalloc(unsigned long size)
 628{
 629	if (size > PAGE_SIZE)
 630		return vzalloc(size);
 631	else
 632		return kzalloc(size, GFP_KERNEL);
 633}
 634
 635static void kvm_destroy_devices(struct kvm *kvm)
 636{
 637	struct kvm_device *dev, *tmp;
 638
 
 
 
 
 
 639	list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
 640		list_del(&dev->vm_node);
 641		dev->ops->destroy(dev);
 642	}
 643}
 644
 645static void kvm_destroy_vm(struct kvm *kvm)
 646{
 647	int i;
 648	struct mm_struct *mm = kvm->mm;
 649
 
 
 
 650	kvm_arch_sync_events(kvm);
 651	spin_lock(&kvm_lock);
 652	list_del(&kvm->vm_list);
 653	spin_unlock(&kvm_lock);
 
 
 654	kvm_free_irq_routing(kvm);
 655	for (i = 0; i < KVM_NR_BUSES; i++)
 656		kvm_io_bus_destroy(kvm->buses[i]);
 
 
 
 
 
 657	kvm_coalesced_mmio_free(kvm);
 658#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 659	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 660#else
 661	kvm_arch_flush_shadow_all(kvm);
 662#endif
 663	kvm_arch_destroy_vm(kvm);
 664	kvm_destroy_devices(kvm);
 665	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
 666		kvm_free_memslots(kvm, kvm->memslots[i]);
 667	cleanup_srcu_struct(&kvm->irq_srcu);
 668	cleanup_srcu_struct(&kvm->srcu);
 669	kvm_arch_free_vm(kvm);
 670	preempt_notifier_dec();
 671	hardware_disable_all();
 672	mmdrop(mm);
 673}
 674
 675void kvm_get_kvm(struct kvm *kvm)
 676{
 677	atomic_inc(&kvm->users_count);
 678}
 679EXPORT_SYMBOL_GPL(kvm_get_kvm);
 680
 681void kvm_put_kvm(struct kvm *kvm)
 682{
 683	if (atomic_dec_and_test(&kvm->users_count))
 684		kvm_destroy_vm(kvm);
 685}
 686EXPORT_SYMBOL_GPL(kvm_put_kvm);
 687
 
 
 
 
 
 
 
 
 
 
 
 
 688
 689static int kvm_vm_release(struct inode *inode, struct file *filp)
 690{
 691	struct kvm *kvm = filp->private_data;
 692
 693	kvm_irqfd_release(kvm);
 694
 695	kvm_put_kvm(kvm);
 696	return 0;
 697}
 698
 699/*
 700 * Allocation size is twice as large as the actual dirty bitmap size.
 701 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
 702 */
 703static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 704{
 705	unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 706
 707	memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
 708	if (!memslot->dirty_bitmap)
 709		return -ENOMEM;
 710
 711	return 0;
 712}
 713
 714/*
 715 * Insert memslot and re-sort memslots based on their GFN,
 716 * so binary search could be used to lookup GFN.
 717 * Sorting algorithm takes advantage of having initially
 718 * sorted array and known changed memslot position.
 719 */
 720static void update_memslots(struct kvm_memslots *slots,
 721			    struct kvm_memory_slot *new)
 722{
 723	int id = new->id;
 724	int i = slots->id_to_index[id];
 725	struct kvm_memory_slot *mslots = slots->memslots;
 
 726
 727	WARN_ON(mslots[i].id != id);
 728	if (!new->npages) {
 729		WARN_ON(!mslots[i].npages);
 730		if (mslots[i].npages)
 731			slots->used_slots--;
 732	} else {
 733		if (!mslots[i].npages)
 734			slots->used_slots++;
 
 
 
 735	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 736
 737	while (i < KVM_MEM_SLOTS_NUM - 1 &&
 738	       new->base_gfn <= mslots[i + 1].base_gfn) {
 739		if (!mslots[i + 1].npages)
 
 
 
 
 
 
 
 
 740			break;
 
 
 
 
 741		mslots[i] = mslots[i + 1];
 742		slots->id_to_index[mslots[i].id] = i;
 743		i++;
 744	}
 
 
 745
 746	/*
 747	 * The ">=" is needed when creating a slot with base_gfn == 0,
 748	 * so that it moves before all those with base_gfn == npages == 0.
 749	 *
 750	 * On the other hand, if new->npages is zero, the above loop has
 751	 * already left i pointing to the beginning of the empty part of
 752	 * mslots, and the ">=" would move the hole backwards in this
 753	 * case---which is wrong.  So skip the loop when deleting a slot.
 754	 */
 755	if (new->npages) {
 756		while (i > 0 &&
 757		       new->base_gfn >= mslots[i - 1].base_gfn) {
 758			mslots[i] = mslots[i - 1];
 759			slots->id_to_index[mslots[i].id] = i;
 760			i--;
 761		}
 762	} else
 763		WARN_ON_ONCE(i != slots->used_slots);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 764
 765	mslots[i] = *new;
 766	slots->id_to_index[mslots[i].id] = i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 767}
 768
 769static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
 770{
 771	u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 772
 773#ifdef __KVM_HAVE_READONLY_MEM
 774	valid_flags |= KVM_MEM_READONLY;
 775#endif
 776
 777	if (mem->flags & ~valid_flags)
 778		return -EINVAL;
 779
 780	return 0;
 781}
 782
 783static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
 784		int as_id, struct kvm_memslots *slots)
 785{
 786	struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
 
 
 
 
 
 
 787
 788	/*
 789	 * Set the low bit in the generation, which disables SPTE caching
 790	 * until the end of synchronize_srcu_expedited.
 
 791	 */
 792	WARN_ON(old_memslots->generation & 1);
 793	slots->generation = old_memslots->generation + 1;
 794
 795	rcu_assign_pointer(kvm->memslots[as_id], slots);
 796	synchronize_srcu_expedited(&kvm->srcu);
 797
 798	/*
 799	 * Increment the new memslot generation a second time. This prevents
 800	 * vm exits that race with memslot updates from caching a memslot
 801	 * generation that will (potentially) be valid forever.
 
 802	 */
 803	slots->generation++;
 804
 805	kvm_arch_memslots_updated(kvm, slots);
 
 
 
 
 
 
 
 
 
 
 
 806
 807	return old_memslots;
 808}
 809
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 810/*
 811 * Allocate some memory and give it an address in the guest physical address
 812 * space.
 813 *
 814 * Discontiguous memory is allowed, mostly for framebuffers.
 815 *
 816 * Must be called holding kvm->slots_lock for write.
 817 */
 818int __kvm_set_memory_region(struct kvm *kvm,
 819			    const struct kvm_userspace_memory_region *mem)
 820{
 821	int r;
 822	gfn_t base_gfn;
 823	unsigned long npages;
 824	struct kvm_memory_slot *slot;
 825	struct kvm_memory_slot old, new;
 826	struct kvm_memslots *slots = NULL, *old_memslots;
 827	int as_id, id;
 828	enum kvm_mr_change change;
 
 
 829
 830	r = check_memory_region_flags(mem);
 831	if (r)
 832		goto out;
 833
 834	r = -EINVAL;
 835	as_id = mem->slot >> 16;
 836	id = (u16)mem->slot;
 837
 838	/* General sanity checks */
 839	if (mem->memory_size & (PAGE_SIZE - 1))
 840		goto out;
 841	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 842		goto out;
 843	/* We can read the guest memory with __xxx_user() later on. */
 844	if ((id < KVM_USER_MEM_SLOTS) &&
 845	    ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
 846	     !access_ok(VERIFY_WRITE,
 847			(void __user *)(unsigned long)mem->userspace_addr,
 848			mem->memory_size)))
 849		goto out;
 850	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
 851		goto out;
 852	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 853		goto out;
 854
 855	slot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
 856	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 857	npages = mem->memory_size >> PAGE_SHIFT;
 858
 859	if (npages > KVM_MEM_MAX_NR_PAGES)
 860		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 861
 862	new = old = *slot;
 
 863
 
 864	new.id = id;
 865	new.base_gfn = base_gfn;
 866	new.npages = npages;
 867	new.flags = mem->flags;
 
 868
 869	if (npages) {
 870		if (!old.npages)
 871			change = KVM_MR_CREATE;
 872		else { /* Modify an existing slot. */
 873			if ((mem->userspace_addr != old.userspace_addr) ||
 874			    (npages != old.npages) ||
 875			    ((new.flags ^ old.flags) & KVM_MEM_READONLY))
 876				goto out;
 877
 878			if (base_gfn != old.base_gfn)
 879				change = KVM_MR_MOVE;
 880			else if (new.flags != old.flags)
 881				change = KVM_MR_FLAGS_ONLY;
 882			else { /* Nothing to change. */
 883				r = 0;
 884				goto out;
 885			}
 886		}
 887	} else {
 888		if (!old.npages)
 889			goto out;
 890
 891		change = KVM_MR_DELETE;
 892		new.base_gfn = 0;
 893		new.flags = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 894	}
 895
 896	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 897		/* Check for overlaps */
 898		r = -EEXIST;
 899		kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) {
 900			if ((slot->id >= KVM_USER_MEM_SLOTS) ||
 901			    (slot->id == id))
 902				continue;
 903			if (!((base_gfn + npages <= slot->base_gfn) ||
 904			      (base_gfn >= slot->base_gfn + slot->npages)))
 905				goto out;
 906		}
 907	}
 908
 909	/* Free page dirty bitmap if unneeded */
 910	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 911		new.dirty_bitmap = NULL;
 
 
 
 
 912
 913	r = -ENOMEM;
 914	if (change == KVM_MR_CREATE) {
 915		new.userspace_addr = mem->userspace_addr;
 916
 917		if (kvm_arch_create_memslot(kvm, &new, npages))
 918			goto out_free;
 919	}
 920
 921	/* Allocate page dirty bitmap if needed */
 922	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 923		if (kvm_create_dirty_bitmap(&new) < 0)
 924			goto out_free;
 925	}
 926
 927	slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
 928	if (!slots)
 929		goto out_free;
 930	memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));
 931
 932	if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
 933		slot = id_to_memslot(slots, id);
 934		slot->flags |= KVM_MEMSLOT_INVALID;
 935
 936		old_memslots = install_new_memslots(kvm, as_id, slots);
 937
 938		/* slot was deleted or moved, clear iommu mapping */
 939		kvm_iommu_unmap_pages(kvm, &old);
 940		/* From this point no new shadow pages pointing to a deleted,
 941		 * or moved, memslot will be created.
 942		 *
 943		 * validation of sp->gfn happens in:
 944		 *	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
 945		 *	- kvm_is_visible_gfn (mmu_check_roots)
 946		 */
 947		kvm_arch_flush_shadow_memslot(kvm, slot);
 948
 949		/*
 950		 * We can re-use the old_memslots from above, the only difference
 951		 * from the currently installed memslots is the invalid flag.  This
 952		 * will get overwritten by update_memslots anyway.
 953		 */
 954		slots = old_memslots;
 955	}
 956
 957	r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
 958	if (r)
 959		goto out_slots;
 960
 961	/* actual memory is freed via old in kvm_free_memslot below */
 962	if (change == KVM_MR_DELETE) {
 963		new.dirty_bitmap = NULL;
 964		memset(&new.arch, 0, sizeof(new.arch));
 965	}
 966
 967	update_memslots(slots, &new);
 968	old_memslots = install_new_memslots(kvm, as_id, slots);
 969
 970	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
 971
 972	kvm_free_memslot(kvm, &old, &new);
 973	kvfree(old_memslots);
 974
 975	/*
 976	 * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
 977	 * un-mapped and re-mapped if their base changes.  Since base change
 978	 * unmapping is handled above with slot deletion, mapping alone is
 979	 * needed here.  Anything else the iommu might care about for existing
 980	 * slots (size changes, userspace addr changes and read-only flag
 981	 * changes) is disallowed above, so any other attribute changes getting
 982	 * here can be skipped.
 983	 */
 984	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 985		r = kvm_iommu_map_pages(kvm, &new);
 986		return r;
 987	}
 988
 
 
 989	return 0;
 990
 991out_slots:
 992	kvfree(slots);
 993out_free:
 994	kvm_free_memslot(kvm, &new, &old);
 995out:
 996	return r;
 997}
 998EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 999
1000int kvm_set_memory_region(struct kvm *kvm,
1001			  const struct kvm_userspace_memory_region *mem)
1002{
1003	int r;
1004
1005	mutex_lock(&kvm->slots_lock);
1006	r = __kvm_set_memory_region(kvm, mem);
1007	mutex_unlock(&kvm->slots_lock);
1008	return r;
1009}
1010EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1011
1012static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1013					  struct kvm_userspace_memory_region *mem)
1014{
1015	if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1016		return -EINVAL;
1017
1018	return kvm_set_memory_region(kvm, mem);
1019}
1020
1021int kvm_get_dirty_log(struct kvm *kvm,
1022			struct kvm_dirty_log *log, int *is_dirty)
 
 
 
 
 
 
 
 
1023{
1024	struct kvm_memslots *slots;
1025	struct kvm_memory_slot *memslot;
1026	int r, i, as_id, id;
1027	unsigned long n;
1028	unsigned long any = 0;
1029
1030	r = -EINVAL;
 
 
 
 
 
 
1031	as_id = log->slot >> 16;
1032	id = (u16)log->slot;
1033	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1034		goto out;
1035
1036	slots = __kvm_memslots(kvm, as_id);
1037	memslot = id_to_memslot(slots, id);
1038	r = -ENOENT;
1039	if (!memslot->dirty_bitmap)
1040		goto out;
1041
1042	n = kvm_dirty_bitmap_bytes(memslot);
 
 
1043
1044	for (i = 0; !any && i < n/sizeof(long); ++i)
1045		any = memslot->dirty_bitmap[i];
1046
1047	r = -EFAULT;
1048	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1049		goto out;
1050
1051	if (any)
1052		*is_dirty = 1;
1053
1054	r = 0;
1055out:
1056	return r;
1057}
1058EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
1059
1060#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
1061/**
1062 * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
1063 *	are dirty write protect them for next write.
1064 * @kvm:	pointer to kvm instance
1065 * @log:	slot id and address to which we copy the log
1066 * @is_dirty:	flag set if any page is dirty
1067 *
1068 * We need to keep it in mind that VCPU threads can write to the bitmap
1069 * concurrently. So, to avoid losing track of dirty pages we keep the
1070 * following order:
1071 *
1072 *    1. Take a snapshot of the bit and clear it if needed.
1073 *    2. Write protect the corresponding page.
1074 *    3. Copy the snapshot to the userspace.
1075 *    4. Upon return caller flushes TLB's if needed.
1076 *
1077 * Between 2 and 4, the guest may write to the page using the remaining TLB
1078 * entry.  This is not a problem because the page is reported dirty using
1079 * the snapshot taken before and step 4 ensures that writes done after
1080 * exiting to userspace will be logged for the next call.
1081 *
1082 */
1083int kvm_get_dirty_log_protect(struct kvm *kvm,
1084			struct kvm_dirty_log *log, bool *is_dirty)
1085{
1086	struct kvm_memslots *slots;
1087	struct kvm_memory_slot *memslot;
1088	int r, i, as_id, id;
1089	unsigned long n;
1090	unsigned long *dirty_bitmap;
1091	unsigned long *dirty_bitmap_buffer;
 
 
 
 
 
1092
1093	r = -EINVAL;
1094	as_id = log->slot >> 16;
1095	id = (u16)log->slot;
1096	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1097		goto out;
1098
1099	slots = __kvm_memslots(kvm, as_id);
1100	memslot = id_to_memslot(slots, id);
 
 
1101
1102	dirty_bitmap = memslot->dirty_bitmap;
1103	r = -ENOENT;
1104	if (!dirty_bitmap)
1105		goto out;
1106
1107	n = kvm_dirty_bitmap_bytes(memslot);
1108
1109	dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long);
1110	memset(dirty_bitmap_buffer, 0, n);
1111
1112	spin_lock(&kvm->mmu_lock);
1113	*is_dirty = false;
1114	for (i = 0; i < n / sizeof(long); i++) {
1115		unsigned long mask;
1116		gfn_t offset;
 
 
 
 
 
 
 
1117
1118		if (!dirty_bitmap[i])
1119			continue;
 
 
1120
1121		*is_dirty = true;
 
1122
1123		mask = xchg(&dirty_bitmap[i], 0);
1124		dirty_bitmap_buffer[i] = mask;
 
1125
1126		if (mask) {
1127			offset = i * BITS_PER_LONG;
1128			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1129								offset, mask);
1130		}
 
1131	}
1132
1133	spin_unlock(&kvm->mmu_lock);
 
1134
1135	r = -EFAULT;
1136	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
1137		goto out;
 
 
1138
1139	r = 0;
1140out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1141	return r;
1142}
1143EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
1144#endif
1145
1146bool kvm_largepages_enabled(void)
 
 
 
 
 
 
 
1147{
1148	return largepages_enabled;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1149}
1150
1151void kvm_disable_largepages(void)
 
1152{
1153	largepages_enabled = false;
 
 
 
 
 
 
 
1154}
1155EXPORT_SYMBOL_GPL(kvm_disable_largepages);
1156
1157struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1158{
1159	return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1160}
1161EXPORT_SYMBOL_GPL(gfn_to_memslot);
1162
1163struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
1164{
1165	return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
1166}
 
1167
1168bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1169{
1170	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1171
1172	if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1173	      memslot->flags & KVM_MEMSLOT_INVALID)
1174		return false;
1175
1176	return true;
1177}
1178EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1179
1180unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
 
 
 
 
 
 
 
 
1181{
1182	struct vm_area_struct *vma;
1183	unsigned long addr, size;
1184
1185	size = PAGE_SIZE;
1186
1187	addr = gfn_to_hva(kvm, gfn);
1188	if (kvm_is_error_hva(addr))
1189		return PAGE_SIZE;
1190
1191	down_read(&current->mm->mmap_sem);
1192	vma = find_vma(current->mm, addr);
1193	if (!vma)
1194		goto out;
1195
1196	size = vma_kernel_pagesize(vma);
1197
1198out:
1199	up_read(&current->mm->mmap_sem);
1200
1201	return size;
1202}
1203
1204static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1205{
1206	return slot->flags & KVM_MEM_READONLY;
1207}
1208
1209static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1210				       gfn_t *nr_pages, bool write)
1211{
1212	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1213		return KVM_HVA_ERR_BAD;
1214
1215	if (memslot_is_readonly(slot) && write)
1216		return KVM_HVA_ERR_RO_BAD;
1217
1218	if (nr_pages)
1219		*nr_pages = slot->npages - (gfn - slot->base_gfn);
1220
1221	return __gfn_to_hva_memslot(slot, gfn);
1222}
1223
1224static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1225				     gfn_t *nr_pages)
1226{
1227	return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1228}
1229
1230unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1231					gfn_t gfn)
1232{
1233	return gfn_to_hva_many(slot, gfn, NULL);
1234}
1235EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1236
1237unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1238{
1239	return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1240}
1241EXPORT_SYMBOL_GPL(gfn_to_hva);
1242
1243unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
1244{
1245	return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
1246}
1247EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);
1248
1249/*
1250 * If writable is set to false, the hva returned by this function is only
1251 * allowed to be read.
 
 
 
 
1252 */
1253unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
1254				      gfn_t gfn, bool *writable)
1255{
1256	unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1257
1258	if (!kvm_is_error_hva(hva) && writable)
1259		*writable = !memslot_is_readonly(slot);
1260
1261	return hva;
1262}
1263
1264unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1265{
1266	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1267
1268	return gfn_to_hva_memslot_prot(slot, gfn, writable);
1269}
1270
1271unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
1272{
1273	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1274
1275	return gfn_to_hva_memslot_prot(slot, gfn, writable);
1276}
1277
1278static int get_user_page_nowait(unsigned long start, int write,
1279		struct page **page)
1280{
1281	int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1282
1283	if (write)
1284		flags |= FOLL_WRITE;
1285
1286	return __get_user_pages(current, current->mm, start, 1, flags, page,
1287			NULL, NULL);
1288}
1289
1290static inline int check_user_page_hwpoison(unsigned long addr)
1291{
1292	int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1293
1294	rc = __get_user_pages(current, current->mm, addr, 1,
1295			      flags, NULL, NULL, NULL);
1296	return rc == -EHWPOISON;
1297}
1298
1299/*
1300 * The atomic path to get the writable pfn which will be stored in @pfn,
1301 * true indicates success, otherwise false is returned.
 
1302 */
1303static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1304			    bool write_fault, bool *writable, kvm_pfn_t *pfn)
1305{
1306	struct page *page[1];
1307	int npages;
1308
1309	if (!(async || atomic))
1310		return false;
1311
1312	/*
1313	 * Fast pin a writable pfn only if it is a write fault request
1314	 * or the caller allows to map a writable pfn for a read fault
1315	 * request.
1316	 */
1317	if (!(write_fault || writable))
1318		return false;
1319
1320	npages = __get_user_pages_fast(addr, 1, 1, page);
1321	if (npages == 1) {
1322		*pfn = page_to_pfn(page[0]);
1323
1324		if (writable)
1325			*writable = true;
1326		return true;
1327	}
1328
1329	return false;
1330}
1331
1332/*
1333 * The slow path to get the pfn of the specified host virtual address,
1334 * 1 indicates success, -errno is returned if error is detected.
1335 */
1336static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1337			   bool *writable, kvm_pfn_t *pfn)
1338{
1339	struct page *page[1];
 
1340	int npages = 0;
1341
1342	might_sleep();
1343
1344	if (writable)
1345		*writable = write_fault;
1346
1347	if (async) {
1348		down_read(&current->mm->mmap_sem);
1349		npages = get_user_page_nowait(addr, write_fault, page);
1350		up_read(&current->mm->mmap_sem);
1351	} else
1352		npages = __get_user_pages_unlocked(current, current->mm, addr, 1,
1353						   write_fault, 0, page,
1354						   FOLL_TOUCH|FOLL_HWPOISON);
1355	if (npages != 1)
1356		return npages;
1357
1358	/* map read fault as writable if possible */
1359	if (unlikely(!write_fault) && writable) {
1360		struct page *wpage[1];
1361
1362		npages = __get_user_pages_fast(addr, 1, 1, wpage);
1363		if (npages == 1) {
1364			*writable = true;
1365			put_page(page[0]);
1366			page[0] = wpage[0];
1367		}
1368
1369		npages = 1;
1370	}
1371	*pfn = page_to_pfn(page[0]);
1372	return npages;
1373}
1374
1375static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1376{
1377	if (unlikely(!(vma->vm_flags & VM_READ)))
1378		return false;
1379
1380	if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1381		return false;
1382
1383	return true;
1384}
1385
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1386/*
1387 * Pin guest page in memory and return its pfn.
1388 * @addr: host virtual address which maps memory to the guest
1389 * @atomic: whether this function can sleep
1390 * @async: whether this function need to wait IO complete if the
1391 *         host page is not in the memory
1392 * @write_fault: whether we should get a writable host page
1393 * @writable: whether it allows to map a writable host page for !@write_fault
1394 *
1395 * The function will map a writable host page for these two cases:
1396 * 1): @write_fault = true
1397 * 2): @write_fault = false && @writable, @writable will tell the caller
1398 *     whether the mapping is writable.
1399 */
1400static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1401			bool write_fault, bool *writable)
1402{
1403	struct vm_area_struct *vma;
1404	kvm_pfn_t pfn = 0;
1405	int npages;
1406
1407	/* we can do it either atomically or asynchronously, not both */
1408	BUG_ON(atomic && async);
1409
1410	if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1411		return pfn;
1412
1413	if (atomic)
1414		return KVM_PFN_ERR_FAULT;
1415
1416	npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1417	if (npages == 1)
1418		return pfn;
1419
1420	down_read(&current->mm->mmap_sem);
1421	if (npages == -EHWPOISON ||
1422	      (!async && check_user_page_hwpoison(addr))) {
1423		pfn = KVM_PFN_ERR_HWPOISON;
1424		goto exit;
1425	}
1426
1427	vma = find_vma_intersection(current->mm, addr, addr + 1);
 
1428
1429	if (vma == NULL)
1430		pfn = KVM_PFN_ERR_FAULT;
1431	else if ((vma->vm_flags & VM_PFNMAP)) {
1432		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1433			vma->vm_pgoff;
1434		BUG_ON(!kvm_is_reserved_pfn(pfn));
 
 
1435	} else {
1436		if (async && vma_is_valid(vma, write_fault))
1437			*async = true;
1438		pfn = KVM_PFN_ERR_FAULT;
1439	}
1440exit:
1441	up_read(&current->mm->mmap_sem);
1442	return pfn;
1443}
1444
1445kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn,
1446			       bool atomic, bool *async, bool write_fault,
1447			       bool *writable)
1448{
1449	unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1450
 
 
 
1451	if (addr == KVM_HVA_ERR_RO_BAD) {
1452		if (writable)
1453			*writable = false;
1454		return KVM_PFN_ERR_RO_FAULT;
1455	}
1456
1457	if (kvm_is_error_hva(addr)) {
1458		if (writable)
1459			*writable = false;
1460		return KVM_PFN_NOSLOT;
1461	}
1462
1463	/* Do not map writable pfn in the readonly memslot. */
1464	if (writable && memslot_is_readonly(slot)) {
1465		*writable = false;
1466		writable = NULL;
1467	}
1468
1469	return hva_to_pfn(addr, atomic, async, write_fault,
1470			  writable);
1471}
1472EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
1473
1474kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1475		      bool *writable)
1476{
1477	return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
1478				    write_fault, writable);
1479}
1480EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1481
1482kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1483{
1484	return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1485}
1486EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
1487
1488kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1489{
1490	return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1491}
1492EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1493
1494kvm_pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1495{
1496	return gfn_to_pfn_memslot_atomic(gfn_to_memslot(kvm, gfn), gfn);
1497}
1498EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1499
1500kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
1501{
1502	return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1503}
1504EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
1505
1506kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1507{
1508	return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
1509}
1510EXPORT_SYMBOL_GPL(gfn_to_pfn);
1511
1512kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1513{
1514	return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1515}
1516EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
1517
1518int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
1519			    struct page **pages, int nr_pages)
1520{
1521	unsigned long addr;
1522	gfn_t entry;
1523
1524	addr = gfn_to_hva_many(slot, gfn, &entry);
1525	if (kvm_is_error_hva(addr))
1526		return -1;
1527
1528	if (entry < nr_pages)
1529		return 0;
1530
1531	return __get_user_pages_fast(addr, nr_pages, 1, pages);
1532}
1533EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1534
1535static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
1536{
1537	if (is_error_noslot_pfn(pfn))
1538		return KVM_ERR_PTR_BAD_PAGE;
1539
1540	if (kvm_is_reserved_pfn(pfn)) {
1541		WARN_ON(1);
1542		return KVM_ERR_PTR_BAD_PAGE;
1543	}
1544
1545	return pfn_to_page(pfn);
1546}
1547
1548struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1549{
1550	kvm_pfn_t pfn;
1551
1552	pfn = gfn_to_pfn(kvm, gfn);
1553
1554	return kvm_pfn_to_page(pfn);
1555}
1556EXPORT_SYMBOL_GPL(gfn_to_page);
1557
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1558struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
1559{
1560	kvm_pfn_t pfn;
1561
1562	pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);
1563
1564	return kvm_pfn_to_page(pfn);
1565}
1566EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);
1567
1568void kvm_release_page_clean(struct page *page)
1569{
1570	WARN_ON(is_error_page(page));
1571
1572	kvm_release_pfn_clean(page_to_pfn(page));
1573}
1574EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1575
1576void kvm_release_pfn_clean(kvm_pfn_t pfn)
1577{
1578	if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
1579		put_page(pfn_to_page(pfn));
1580}
1581EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1582
1583void kvm_release_page_dirty(struct page *page)
1584{
1585	WARN_ON(is_error_page(page));
1586
1587	kvm_release_pfn_dirty(page_to_pfn(page));
1588}
1589EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1590
1591static void kvm_release_pfn_dirty(kvm_pfn_t pfn)
1592{
1593	kvm_set_pfn_dirty(pfn);
1594	kvm_release_pfn_clean(pfn);
1595}
 
1596
1597void kvm_set_pfn_dirty(kvm_pfn_t pfn)
1598{
1599	if (!kvm_is_reserved_pfn(pfn)) {
1600		struct page *page = pfn_to_page(pfn);
1601
1602		if (!PageReserved(page))
1603			SetPageDirty(page);
1604	}
1605}
1606EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1607
1608void kvm_set_pfn_accessed(kvm_pfn_t pfn)
1609{
1610	if (!kvm_is_reserved_pfn(pfn))
1611		mark_page_accessed(pfn_to_page(pfn));
1612}
1613EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1614
1615void kvm_get_pfn(kvm_pfn_t pfn)
1616{
1617	if (!kvm_is_reserved_pfn(pfn))
1618		get_page(pfn_to_page(pfn));
1619}
1620EXPORT_SYMBOL_GPL(kvm_get_pfn);
1621
1622static int next_segment(unsigned long len, int offset)
1623{
1624	if (len > PAGE_SIZE - offset)
1625		return PAGE_SIZE - offset;
1626	else
1627		return len;
1628}
1629
1630static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
1631				 void *data, int offset, int len)
1632{
1633	int r;
1634	unsigned long addr;
1635
1636	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1637	if (kvm_is_error_hva(addr))
1638		return -EFAULT;
1639	r = __copy_from_user(data, (void __user *)addr + offset, len);
1640	if (r)
1641		return -EFAULT;
1642	return 0;
1643}
1644
1645int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1646			int len)
1647{
1648	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1649
1650	return __kvm_read_guest_page(slot, gfn, data, offset, len);
1651}
1652EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1653
1654int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
1655			     int offset, int len)
1656{
1657	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1658
1659	return __kvm_read_guest_page(slot, gfn, data, offset, len);
1660}
1661EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);
1662
1663int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1664{
1665	gfn_t gfn = gpa >> PAGE_SHIFT;
1666	int seg;
1667	int offset = offset_in_page(gpa);
1668	int ret;
1669
1670	while ((seg = next_segment(len, offset)) != 0) {
1671		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1672		if (ret < 0)
1673			return ret;
1674		offset = 0;
1675		len -= seg;
1676		data += seg;
1677		++gfn;
1678	}
1679	return 0;
1680}
1681EXPORT_SYMBOL_GPL(kvm_read_guest);
1682
1683int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
1684{
1685	gfn_t gfn = gpa >> PAGE_SHIFT;
1686	int seg;
1687	int offset = offset_in_page(gpa);
1688	int ret;
1689
1690	while ((seg = next_segment(len, offset)) != 0) {
1691		ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
1692		if (ret < 0)
1693			return ret;
1694		offset = 0;
1695		len -= seg;
1696		data += seg;
1697		++gfn;
1698	}
1699	return 0;
1700}
1701EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
1702
1703static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
1704			           void *data, int offset, unsigned long len)
1705{
1706	int r;
1707	unsigned long addr;
1708
1709	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1710	if (kvm_is_error_hva(addr))
1711		return -EFAULT;
1712	pagefault_disable();
1713	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1714	pagefault_enable();
1715	if (r)
1716		return -EFAULT;
1717	return 0;
1718}
1719
1720int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1721			  unsigned long len)
1722{
1723	gfn_t gfn = gpa >> PAGE_SHIFT;
1724	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1725	int offset = offset_in_page(gpa);
1726
1727	return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
1728}
1729EXPORT_SYMBOL_GPL(kvm_read_guest_atomic);
1730
1731int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
1732			       void *data, unsigned long len)
1733{
1734	gfn_t gfn = gpa >> PAGE_SHIFT;
1735	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1736	int offset = offset_in_page(gpa);
1737
1738	return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
1739}
1740EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
1741
1742static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
 
1743			          const void *data, int offset, int len)
1744{
1745	int r;
1746	unsigned long addr;
1747
1748	addr = gfn_to_hva_memslot(memslot, gfn);
1749	if (kvm_is_error_hva(addr))
1750		return -EFAULT;
1751	r = __copy_to_user((void __user *)addr + offset, data, len);
1752	if (r)
1753		return -EFAULT;
1754	mark_page_dirty_in_slot(memslot, gfn);
1755	return 0;
1756}
1757
1758int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
1759			 const void *data, int offset, int len)
1760{
1761	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1762
1763	return __kvm_write_guest_page(slot, gfn, data, offset, len);
1764}
1765EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1766
1767int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
1768			      const void *data, int offset, int len)
1769{
1770	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1771
1772	return __kvm_write_guest_page(slot, gfn, data, offset, len);
1773}
1774EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
1775
1776int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1777		    unsigned long len)
1778{
1779	gfn_t gfn = gpa >> PAGE_SHIFT;
1780	int seg;
1781	int offset = offset_in_page(gpa);
1782	int ret;
1783
1784	while ((seg = next_segment(len, offset)) != 0) {
1785		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1786		if (ret < 0)
1787			return ret;
1788		offset = 0;
1789		len -= seg;
1790		data += seg;
1791		++gfn;
1792	}
1793	return 0;
1794}
1795EXPORT_SYMBOL_GPL(kvm_write_guest);
1796
1797int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
1798		         unsigned long len)
1799{
1800	gfn_t gfn = gpa >> PAGE_SHIFT;
1801	int seg;
1802	int offset = offset_in_page(gpa);
1803	int ret;
1804
1805	while ((seg = next_segment(len, offset)) != 0) {
1806		ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
1807		if (ret < 0)
1808			return ret;
1809		offset = 0;
1810		len -= seg;
1811		data += seg;
1812		++gfn;
1813	}
1814	return 0;
1815}
1816EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
1817
1818int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1819			      gpa_t gpa, unsigned long len)
 
1820{
1821	struct kvm_memslots *slots = kvm_memslots(kvm);
1822	int offset = offset_in_page(gpa);
1823	gfn_t start_gfn = gpa >> PAGE_SHIFT;
1824	gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1825	gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1826	gfn_t nr_pages_avail;
1827
1828	ghc->gpa = gpa;
1829	ghc->generation = slots->generation;
1830	ghc->len = len;
1831	ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1832	ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
1833	if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1834		ghc->hva += offset;
1835	} else {
1836		/*
1837		 * If the requested region crosses two memslots, we still
1838		 * verify that the entire region is valid here.
1839		 */
1840		while (start_gfn <= end_gfn) {
1841			ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1842			ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1843						   &nr_pages_avail);
1844			if (kvm_is_error_hva(ghc->hva))
1845				return -EFAULT;
1846			start_gfn += nr_pages_avail;
1847		}
1848		/* Use the slow path for cross page reads and writes. */
1849		ghc->memslot = NULL;
1850	}
 
 
1851	return 0;
1852}
 
 
 
 
 
 
 
1853EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1854
1855int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1856			   void *data, unsigned long len)
 
1857{
1858	struct kvm_memslots *slots = kvm_memslots(kvm);
1859	int r;
 
1860
1861	BUG_ON(len > ghc->len);
1862
1863	if (slots->generation != ghc->generation)
1864		kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1865
1866	if (unlikely(!ghc->memslot))
1867		return kvm_write_guest(kvm, ghc->gpa, data, len);
1868
1869	if (kvm_is_error_hva(ghc->hva))
1870		return -EFAULT;
1871
1872	r = __copy_to_user((void __user *)ghc->hva, data, len);
 
 
 
1873	if (r)
1874		return -EFAULT;
1875	mark_page_dirty_in_slot(ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1876
1877	return 0;
1878}
1879EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1880
1881int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1882			   void *data, unsigned long len)
1883{
 
 
 
 
 
 
 
 
1884	struct kvm_memslots *slots = kvm_memslots(kvm);
1885	int r;
 
1886
1887	BUG_ON(len > ghc->len);
1888
1889	if (slots->generation != ghc->generation)
1890		kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1891
1892	if (unlikely(!ghc->memslot))
1893		return kvm_read_guest(kvm, ghc->gpa, data, len);
 
 
1894
1895	if (kvm_is_error_hva(ghc->hva))
1896		return -EFAULT;
1897
1898	r = __copy_from_user(data, (void __user *)ghc->hva, len);
 
 
 
1899	if (r)
1900		return -EFAULT;
1901
1902	return 0;
1903}
1904EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1905
1906int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
 
1907{
1908	const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
1909
1910	return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
1911}
1912EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1913
1914int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1915{
 
1916	gfn_t gfn = gpa >> PAGE_SHIFT;
1917	int seg;
1918	int offset = offset_in_page(gpa);
1919	int ret;
1920
1921	while ((seg = next_segment(len, offset)) != 0) {
1922		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1923		if (ret < 0)
1924			return ret;
1925		offset = 0;
1926		len -= seg;
1927		++gfn;
1928	}
1929	return 0;
1930}
1931EXPORT_SYMBOL_GPL(kvm_clear_guest);
1932
1933static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
1934				    gfn_t gfn)
 
1935{
1936	if (memslot && memslot->dirty_bitmap) {
1937		unsigned long rel_gfn = gfn - memslot->base_gfn;
 
1938
1939		set_bit_le(rel_gfn, memslot->dirty_bitmap);
 
 
 
 
1940	}
1941}
 
1942
1943void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1944{
1945	struct kvm_memory_slot *memslot;
1946
1947	memslot = gfn_to_memslot(kvm, gfn);
1948	mark_page_dirty_in_slot(memslot, gfn);
1949}
1950EXPORT_SYMBOL_GPL(mark_page_dirty);
1951
1952void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
1953{
1954	struct kvm_memory_slot *memslot;
1955
1956	memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1957	mark_page_dirty_in_slot(memslot, gfn);
1958}
1959EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
1960
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1961static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
1962{
1963	unsigned int old, val, grow;
1964
1965	old = val = vcpu->halt_poll_ns;
 
1966	grow = READ_ONCE(halt_poll_ns_grow);
1967	/* 10us base */
1968	if (val == 0 && grow)
1969		val = 10000;
1970	else
1971		val *= grow;
 
1972
1973	if (val > halt_poll_ns)
1974		val = halt_poll_ns;
1975
1976	vcpu->halt_poll_ns = val;
 
1977	trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
1978}
1979
1980static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
1981{
1982	unsigned int old, val, shrink;
1983
1984	old = val = vcpu->halt_poll_ns;
1985	shrink = READ_ONCE(halt_poll_ns_shrink);
 
1986	if (shrink == 0)
1987		val = 0;
1988	else
1989		val /= shrink;
1990
 
 
 
1991	vcpu->halt_poll_ns = val;
1992	trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
1993}
1994
1995static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
1996{
 
 
 
1997	if (kvm_arch_vcpu_runnable(vcpu)) {
1998		kvm_make_request(KVM_REQ_UNHALT, vcpu);
1999		return -EINTR;
2000	}
2001	if (kvm_cpu_has_pending_timer(vcpu))
2002		return -EINTR;
2003	if (signal_pending(current))
2004		return -EINTR;
 
 
2005
2006	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
2007}
2008
2009/*
2010 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
2011 */
2012void kvm_vcpu_block(struct kvm_vcpu *vcpu)
2013{
2014	ktime_t start, cur;
2015	DECLARE_SWAITQUEUE(wait);
2016	bool waited = false;
2017	u64 block_ns;
2018
2019	start = cur = ktime_get();
2020	if (vcpu->halt_poll_ns) {
 
 
2021		ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
2022
2023		++vcpu->stat.halt_attempted_poll;
2024		do {
2025			/*
2026			 * This sets KVM_REQ_UNHALT if an interrupt
2027			 * arrives.
2028			 */
2029			if (kvm_vcpu_check_block(vcpu) < 0) {
2030				++vcpu->stat.halt_successful_poll;
 
 
2031				goto out;
2032			}
2033			cur = ktime_get();
2034		} while (single_task_running() && ktime_before(cur, stop));
 
2035	}
2036
2037	kvm_arch_vcpu_blocking(vcpu);
2038
2039	for (;;) {
2040		prepare_to_swait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
2041
2042		if (kvm_vcpu_check_block(vcpu) < 0)
2043			break;
2044
2045		waited = true;
2046		schedule();
2047	}
2048
2049	finish_swait(&vcpu->wq, &wait);
2050	cur = ktime_get();
2051
2052	kvm_arch_vcpu_unblocking(vcpu);
2053out:
 
2054	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
2055
2056	if (halt_poll_ns) {
2057		if (block_ns <= vcpu->halt_poll_ns)
2058			;
2059		/* we had a long block, shrink polling */
2060		else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns)
2061			shrink_halt_poll_ns(vcpu);
2062		/* we had a short halt and our poll time is too small */
2063		else if (vcpu->halt_poll_ns < halt_poll_ns &&
2064			block_ns < halt_poll_ns)
2065			grow_halt_poll_ns(vcpu);
2066	} else
2067		vcpu->halt_poll_ns = 0;
 
 
 
 
 
 
 
 
 
2068
2069	trace_kvm_vcpu_wakeup(block_ns, waited);
 
2070}
2071EXPORT_SYMBOL_GPL(kvm_vcpu_block);
2072
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2073#ifndef CONFIG_S390
2074/*
2075 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
2076 */
2077void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
2078{
2079	int me;
2080	int cpu = vcpu->cpu;
2081	struct swait_queue_head *wqp;
2082
2083	wqp = kvm_arch_vcpu_wq(vcpu);
2084	if (swait_active(wqp)) {
2085		swake_up(wqp);
2086		++vcpu->stat.halt_wakeup;
2087	}
2088
2089	me = get_cpu();
2090	if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
2091		if (kvm_arch_vcpu_should_kick(vcpu))
2092			smp_send_reschedule(cpu);
2093	put_cpu();
2094}
2095EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
2096#endif /* !CONFIG_S390 */
2097
2098int kvm_vcpu_yield_to(struct kvm_vcpu *target)
2099{
2100	struct pid *pid;
2101	struct task_struct *task = NULL;
2102	int ret = 0;
2103
2104	rcu_read_lock();
2105	pid = rcu_dereference(target->pid);
2106	if (pid)
2107		task = get_pid_task(pid, PIDTYPE_PID);
2108	rcu_read_unlock();
2109	if (!task)
2110		return ret;
2111	ret = yield_to(task, 1);
2112	put_task_struct(task);
2113
2114	return ret;
2115}
2116EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
2117
2118/*
2119 * Helper that checks whether a VCPU is eligible for directed yield.
2120 * Most eligible candidate to yield is decided by following heuristics:
2121 *
2122 *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
2123 *  (preempted lock holder), indicated by @in_spin_loop.
2124 *  Set at the beiginning and cleared at the end of interception/PLE handler.
2125 *
2126 *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
2127 *  chance last time (mostly it has become eligible now since we have probably
2128 *  yielded to lockholder in last iteration. This is done by toggling
2129 *  @dy_eligible each time a VCPU checked for eligibility.)
2130 *
2131 *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
2132 *  to preempted lock-holder could result in wrong VCPU selection and CPU
2133 *  burning. Giving priority for a potential lock-holder increases lock
2134 *  progress.
2135 *
2136 *  Since algorithm is based on heuristics, accessing another VCPU data without
2137 *  locking does not harm. It may result in trying to yield to  same VCPU, fail
2138 *  and continue with next VCPU and so on.
2139 */
2140static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
2141{
2142#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2143	bool eligible;
2144
2145	eligible = !vcpu->spin_loop.in_spin_loop ||
2146		    vcpu->spin_loop.dy_eligible;
2147
2148	if (vcpu->spin_loop.in_spin_loop)
2149		kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
2150
2151	return eligible;
2152#else
2153	return true;
2154#endif
2155}
2156
2157void kvm_vcpu_on_spin(struct kvm_vcpu *me)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2158{
2159	struct kvm *kvm = me->kvm;
2160	struct kvm_vcpu *vcpu;
2161	int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
2162	int yielded = 0;
2163	int try = 3;
2164	int pass;
2165	int i;
2166
2167	kvm_vcpu_set_in_spin_loop(me, true);
2168	/*
2169	 * We boost the priority of a VCPU that is runnable but not
2170	 * currently running, because it got preempted by something
2171	 * else and called schedule in __vcpu_run.  Hopefully that
2172	 * VCPU is holding the lock that we need and will release it.
2173	 * We approximate round-robin by starting at the last boosted VCPU.
2174	 */
2175	for (pass = 0; pass < 2 && !yielded && try; pass++) {
2176		kvm_for_each_vcpu(i, vcpu, kvm) {
2177			if (!pass && i <= last_boosted_vcpu) {
2178				i = last_boosted_vcpu;
2179				continue;
2180			} else if (pass && i > last_boosted_vcpu)
2181				break;
2182			if (!ACCESS_ONCE(vcpu->preempted))
2183				continue;
2184			if (vcpu == me)
2185				continue;
2186			if (swait_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
 
 
 
 
 
2187				continue;
2188			if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
2189				continue;
2190
2191			yielded = kvm_vcpu_yield_to(vcpu);
2192			if (yielded > 0) {
2193				kvm->last_boosted_vcpu = i;
2194				break;
2195			} else if (yielded < 0) {
2196				try--;
2197				if (!try)
2198					break;
2199			}
2200		}
2201	}
2202	kvm_vcpu_set_in_spin_loop(me, false);
2203
2204	/* Ensure vcpu is not eligible during next spinloop */
2205	kvm_vcpu_set_dy_eligible(me, false);
2206}
2207EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
2208
2209static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2210{
2211	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
 
 
 
 
 
 
 
 
 
 
 
2212	struct page *page;
2213
2214	if (vmf->pgoff == 0)
2215		page = virt_to_page(vcpu->run);
2216#ifdef CONFIG_X86
2217	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
2218		page = virt_to_page(vcpu->arch.pio_data);
2219#endif
2220#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2221	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
2222		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
2223#endif
 
 
 
 
2224	else
2225		return kvm_arch_vcpu_fault(vcpu, vmf);
2226	get_page(page);
2227	vmf->page = page;
2228	return 0;
2229}
2230
2231static const struct vm_operations_struct kvm_vcpu_vm_ops = {
2232	.fault = kvm_vcpu_fault,
2233};
2234
2235static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
2236{
 
 
 
 
 
 
 
 
2237	vma->vm_ops = &kvm_vcpu_vm_ops;
2238	return 0;
2239}
2240
2241static int kvm_vcpu_release(struct inode *inode, struct file *filp)
2242{
2243	struct kvm_vcpu *vcpu = filp->private_data;
2244
2245	kvm_put_kvm(vcpu->kvm);
2246	return 0;
2247}
2248
2249static struct file_operations kvm_vcpu_fops = {
2250	.release        = kvm_vcpu_release,
2251	.unlocked_ioctl = kvm_vcpu_ioctl,
2252#ifdef CONFIG_KVM_COMPAT
2253	.compat_ioctl   = kvm_vcpu_compat_ioctl,
2254#endif
2255	.mmap           = kvm_vcpu_mmap,
2256	.llseek		= noop_llseek,
 
2257};
2258
2259/*
2260 * Allocates an inode for the vcpu.
2261 */
2262static int create_vcpu_fd(struct kvm_vcpu *vcpu)
2263{
2264	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2265}
2266
2267/*
2268 * Creates some virtual cpus.  Good luck creating more than one.
2269 */
2270static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
2271{
2272	int r;
2273	struct kvm_vcpu *vcpu;
 
2274
2275	if (id >= KVM_MAX_VCPUS)
2276		return -EINVAL;
2277
2278	vcpu = kvm_arch_vcpu_create(kvm, id);
2279	if (IS_ERR(vcpu))
2280		return PTR_ERR(vcpu);
 
 
2281
2282	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
2283
2284	r = kvm_arch_vcpu_setup(vcpu);
2285	if (r)
2286		goto vcpu_destroy;
2287
2288	mutex_lock(&kvm->lock);
2289	if (!kvm_vcpu_compatible(vcpu)) {
2290		r = -EINVAL;
2291		goto unlock_vcpu_destroy;
2292	}
2293	if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
2294		r = -EINVAL;
2295		goto unlock_vcpu_destroy;
 
 
 
2296	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2297	if (kvm_get_vcpu_by_id(kvm, id)) {
2298		r = -EEXIST;
2299		goto unlock_vcpu_destroy;
2300	}
2301
2302	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
 
 
 
 
 
2303
2304	/* Now it's all set up, let userspace reach it */
2305	kvm_get_kvm(kvm);
2306	r = create_vcpu_fd(vcpu);
2307	if (r < 0) {
2308		kvm_put_kvm(kvm);
2309		goto unlock_vcpu_destroy;
2310	}
2311
2312	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
2313
2314	/*
2315	 * Pairs with smp_rmb() in kvm_get_vcpu.  Write kvm->vcpus
2316	 * before kvm->online_vcpu's incremented value.
2317	 */
2318	smp_wmb();
2319	atomic_inc(&kvm->online_vcpus);
2320
2321	mutex_unlock(&kvm->lock);
2322	kvm_arch_vcpu_postcreate(vcpu);
 
2323	return r;
2324
2325unlock_vcpu_destroy:
2326	mutex_unlock(&kvm->lock);
2327vcpu_destroy:
 
2328	kvm_arch_vcpu_destroy(vcpu);
 
 
 
 
 
 
 
 
2329	return r;
2330}
2331
2332static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
2333{
2334	if (sigset) {
2335		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
2336		vcpu->sigset_active = 1;
2337		vcpu->sigset = *sigset;
2338	} else
2339		vcpu->sigset_active = 0;
2340	return 0;
2341}
2342
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2343static long kvm_vcpu_ioctl(struct file *filp,
2344			   unsigned int ioctl, unsigned long arg)
2345{
2346	struct kvm_vcpu *vcpu = filp->private_data;
2347	void __user *argp = (void __user *)arg;
2348	int r;
2349	struct kvm_fpu *fpu = NULL;
2350	struct kvm_sregs *kvm_sregs = NULL;
2351
2352	if (vcpu->kvm->mm != current->mm)
2353		return -EIO;
2354
2355	if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
2356		return -EINVAL;
2357
2358#if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
2359	/*
2360	 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
2361	 * so vcpu_load() would break it.
2362	 */
2363	if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_S390_IRQ || ioctl == KVM_INTERRUPT)
2364		return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2365#endif
2366
2367
2368	r = vcpu_load(vcpu);
2369	if (r)
2370		return r;
 
 
 
2371	switch (ioctl) {
2372	case KVM_RUN:
 
2373		r = -EINVAL;
2374		if (arg)
2375			goto out;
2376		if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
 
2377			/* The thread running this VCPU changed. */
2378			struct pid *oldpid = vcpu->pid;
2379			struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
 
 
 
2380
 
2381			rcu_assign_pointer(vcpu->pid, newpid);
2382			if (oldpid)
2383				synchronize_rcu();
2384			put_pid(oldpid);
2385		}
2386		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2387		trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
2388		break;
 
2389	case KVM_GET_REGS: {
2390		struct kvm_regs *kvm_regs;
2391
2392		r = -ENOMEM;
2393		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
2394		if (!kvm_regs)
2395			goto out;
2396		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
2397		if (r)
2398			goto out_free1;
2399		r = -EFAULT;
2400		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2401			goto out_free1;
2402		r = 0;
2403out_free1:
2404		kfree(kvm_regs);
2405		break;
2406	}
2407	case KVM_SET_REGS: {
2408		struct kvm_regs *kvm_regs;
2409
2410		r = -ENOMEM;
2411		kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2412		if (IS_ERR(kvm_regs)) {
2413			r = PTR_ERR(kvm_regs);
2414			goto out;
2415		}
2416		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2417		kfree(kvm_regs);
2418		break;
2419	}
2420	case KVM_GET_SREGS: {
2421		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
 
2422		r = -ENOMEM;
2423		if (!kvm_sregs)
2424			goto out;
2425		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2426		if (r)
2427			goto out;
2428		r = -EFAULT;
2429		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2430			goto out;
2431		r = 0;
2432		break;
2433	}
2434	case KVM_SET_SREGS: {
2435		kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2436		if (IS_ERR(kvm_sregs)) {
2437			r = PTR_ERR(kvm_sregs);
2438			kvm_sregs = NULL;
2439			goto out;
2440		}
2441		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2442		break;
2443	}
2444	case KVM_GET_MP_STATE: {
2445		struct kvm_mp_state mp_state;
2446
2447		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2448		if (r)
2449			goto out;
2450		r = -EFAULT;
2451		if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
2452			goto out;
2453		r = 0;
2454		break;
2455	}
2456	case KVM_SET_MP_STATE: {
2457		struct kvm_mp_state mp_state;
2458
2459		r = -EFAULT;
2460		if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
2461			goto out;
2462		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2463		break;
2464	}
2465	case KVM_TRANSLATE: {
2466		struct kvm_translation tr;
2467
2468		r = -EFAULT;
2469		if (copy_from_user(&tr, argp, sizeof(tr)))
2470			goto out;
2471		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2472		if (r)
2473			goto out;
2474		r = -EFAULT;
2475		if (copy_to_user(argp, &tr, sizeof(tr)))
2476			goto out;
2477		r = 0;
2478		break;
2479	}
2480	case KVM_SET_GUEST_DEBUG: {
2481		struct kvm_guest_debug dbg;
2482
2483		r = -EFAULT;
2484		if (copy_from_user(&dbg, argp, sizeof(dbg)))
2485			goto out;
2486		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2487		break;
2488	}
2489	case KVM_SET_SIGNAL_MASK: {
2490		struct kvm_signal_mask __user *sigmask_arg = argp;
2491		struct kvm_signal_mask kvm_sigmask;
2492		sigset_t sigset, *p;
2493
2494		p = NULL;
2495		if (argp) {
2496			r = -EFAULT;
2497			if (copy_from_user(&kvm_sigmask, argp,
2498					   sizeof(kvm_sigmask)))
2499				goto out;
2500			r = -EINVAL;
2501			if (kvm_sigmask.len != sizeof(sigset))
2502				goto out;
2503			r = -EFAULT;
2504			if (copy_from_user(&sigset, sigmask_arg->sigset,
2505					   sizeof(sigset)))
2506				goto out;
2507			p = &sigset;
2508		}
2509		r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2510		break;
2511	}
2512	case KVM_GET_FPU: {
2513		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2514		r = -ENOMEM;
2515		if (!fpu)
2516			goto out;
2517		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2518		if (r)
2519			goto out;
2520		r = -EFAULT;
2521		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2522			goto out;
2523		r = 0;
2524		break;
2525	}
2526	case KVM_SET_FPU: {
2527		fpu = memdup_user(argp, sizeof(*fpu));
2528		if (IS_ERR(fpu)) {
2529			r = PTR_ERR(fpu);
2530			fpu = NULL;
2531			goto out;
2532		}
2533		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2534		break;
2535	}
 
 
 
 
2536	default:
2537		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2538	}
2539out:
2540	vcpu_put(vcpu);
2541	kfree(fpu);
2542	kfree(kvm_sregs);
2543	return r;
2544}
2545
2546#ifdef CONFIG_KVM_COMPAT
2547static long kvm_vcpu_compat_ioctl(struct file *filp,
2548				  unsigned int ioctl, unsigned long arg)
2549{
2550	struct kvm_vcpu *vcpu = filp->private_data;
2551	void __user *argp = compat_ptr(arg);
2552	int r;
2553
2554	if (vcpu->kvm->mm != current->mm)
2555		return -EIO;
2556
2557	switch (ioctl) {
2558	case KVM_SET_SIGNAL_MASK: {
2559		struct kvm_signal_mask __user *sigmask_arg = argp;
2560		struct kvm_signal_mask kvm_sigmask;
2561		compat_sigset_t csigset;
2562		sigset_t sigset;
2563
2564		if (argp) {
2565			r = -EFAULT;
2566			if (copy_from_user(&kvm_sigmask, argp,
2567					   sizeof(kvm_sigmask)))
2568				goto out;
2569			r = -EINVAL;
2570			if (kvm_sigmask.len != sizeof(csigset))
2571				goto out;
2572			r = -EFAULT;
2573			if (copy_from_user(&csigset, sigmask_arg->sigset,
2574					   sizeof(csigset)))
2575				goto out;
2576			sigset_from_compat(&sigset, &csigset);
2577			r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2578		} else
2579			r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2580		break;
2581	}
2582	default:
2583		r = kvm_vcpu_ioctl(filp, ioctl, arg);
2584	}
2585
2586out:
2587	return r;
2588}
2589#endif
2590
 
 
 
 
 
 
 
 
 
 
2591static int kvm_device_ioctl_attr(struct kvm_device *dev,
2592				 int (*accessor)(struct kvm_device *dev,
2593						 struct kvm_device_attr *attr),
2594				 unsigned long arg)
2595{
2596	struct kvm_device_attr attr;
2597
2598	if (!accessor)
2599		return -EPERM;
2600
2601	if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2602		return -EFAULT;
2603
2604	return accessor(dev, &attr);
2605}
2606
2607static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2608			     unsigned long arg)
2609{
2610	struct kvm_device *dev = filp->private_data;
2611
 
 
 
2612	switch (ioctl) {
2613	case KVM_SET_DEVICE_ATTR:
2614		return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2615	case KVM_GET_DEVICE_ATTR:
2616		return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2617	case KVM_HAS_DEVICE_ATTR:
2618		return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2619	default:
2620		if (dev->ops->ioctl)
2621			return dev->ops->ioctl(dev, ioctl, arg);
2622
2623		return -ENOTTY;
2624	}
2625}
2626
2627static int kvm_device_release(struct inode *inode, struct file *filp)
2628{
2629	struct kvm_device *dev = filp->private_data;
2630	struct kvm *kvm = dev->kvm;
2631
 
 
 
 
 
 
 
2632	kvm_put_kvm(kvm);
2633	return 0;
2634}
2635
2636static const struct file_operations kvm_device_fops = {
2637	.unlocked_ioctl = kvm_device_ioctl,
2638#ifdef CONFIG_KVM_COMPAT
2639	.compat_ioctl = kvm_device_ioctl,
2640#endif
2641	.release = kvm_device_release,
 
 
2642};
2643
2644struct kvm_device *kvm_device_from_filp(struct file *filp)
2645{
2646	if (filp->f_op != &kvm_device_fops)
2647		return NULL;
2648
2649	return filp->private_data;
2650}
2651
2652static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
2653#ifdef CONFIG_KVM_MPIC
2654	[KVM_DEV_TYPE_FSL_MPIC_20]	= &kvm_mpic_ops,
2655	[KVM_DEV_TYPE_FSL_MPIC_42]	= &kvm_mpic_ops,
2656#endif
2657
2658#ifdef CONFIG_KVM_XICS
2659	[KVM_DEV_TYPE_XICS]		= &kvm_xics_ops,
2660#endif
2661};
2662
2663int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
2664{
2665	if (type >= ARRAY_SIZE(kvm_device_ops_table))
2666		return -ENOSPC;
2667
2668	if (kvm_device_ops_table[type] != NULL)
2669		return -EEXIST;
2670
2671	kvm_device_ops_table[type] = ops;
2672	return 0;
2673}
2674
2675void kvm_unregister_device_ops(u32 type)
2676{
2677	if (kvm_device_ops_table[type] != NULL)
2678		kvm_device_ops_table[type] = NULL;
2679}
2680
2681static int kvm_ioctl_create_device(struct kvm *kvm,
2682				   struct kvm_create_device *cd)
2683{
2684	struct kvm_device_ops *ops = NULL;
2685	struct kvm_device *dev;
2686	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
 
2687	int ret;
2688
2689	if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
2690		return -ENODEV;
2691
2692	ops = kvm_device_ops_table[cd->type];
 
2693	if (ops == NULL)
2694		return -ENODEV;
2695
2696	if (test)
2697		return 0;
2698
2699	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2700	if (!dev)
2701		return -ENOMEM;
2702
2703	dev->ops = ops;
2704	dev->kvm = kvm;
2705
2706	ret = ops->create(dev, cd->type);
 
2707	if (ret < 0) {
 
2708		kfree(dev);
2709		return ret;
2710	}
 
 
 
 
 
2711
 
2712	ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
2713	if (ret < 0) {
 
 
 
 
2714		ops->destroy(dev);
2715		return ret;
2716	}
2717
2718	list_add(&dev->vm_node, &kvm->devices);
2719	kvm_get_kvm(kvm);
2720	cd->fd = ret;
2721	return 0;
2722}
2723
2724static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
2725{
2726	switch (arg) {
2727	case KVM_CAP_USER_MEMORY:
2728	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2729	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2730	case KVM_CAP_INTERNAL_ERROR_DATA:
2731#ifdef CONFIG_HAVE_KVM_MSI
2732	case KVM_CAP_SIGNAL_MSI:
2733#endif
2734#ifdef CONFIG_HAVE_KVM_IRQFD
2735	case KVM_CAP_IRQFD:
2736	case KVM_CAP_IRQFD_RESAMPLE:
2737#endif
2738	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
2739	case KVM_CAP_CHECK_EXTENSION_VM:
 
 
 
 
 
 
 
2740		return 1;
 
 
 
 
 
2741#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2742	case KVM_CAP_IRQ_ROUTING:
2743		return KVM_MAX_IRQ_ROUTES;
2744#endif
2745#if KVM_ADDRESS_SPACE_NUM > 1
2746	case KVM_CAP_MULTI_ADDRESS_SPACE:
2747		return KVM_ADDRESS_SPACE_NUM;
2748#endif
 
 
 
 
 
 
 
 
 
 
2749	default:
2750		break;
2751	}
2752	return kvm_vm_ioctl_check_extension(kvm, arg);
2753}
2754
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2755static long kvm_vm_ioctl(struct file *filp,
2756			   unsigned int ioctl, unsigned long arg)
2757{
2758	struct kvm *kvm = filp->private_data;
2759	void __user *argp = (void __user *)arg;
2760	int r;
2761
2762	if (kvm->mm != current->mm)
2763		return -EIO;
2764	switch (ioctl) {
2765	case KVM_CREATE_VCPU:
2766		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2767		break;
 
 
 
 
 
 
 
 
 
2768	case KVM_SET_USER_MEMORY_REGION: {
2769		struct kvm_userspace_memory_region kvm_userspace_mem;
2770
2771		r = -EFAULT;
2772		if (copy_from_user(&kvm_userspace_mem, argp,
2773						sizeof(kvm_userspace_mem)))
2774			goto out;
2775
2776		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2777		break;
2778	}
2779	case KVM_GET_DIRTY_LOG: {
2780		struct kvm_dirty_log log;
2781
2782		r = -EFAULT;
2783		if (copy_from_user(&log, argp, sizeof(log)))
2784			goto out;
2785		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2786		break;
2787	}
2788#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 
 
 
 
 
 
 
 
 
 
 
2789	case KVM_REGISTER_COALESCED_MMIO: {
2790		struct kvm_coalesced_mmio_zone zone;
2791
2792		r = -EFAULT;
2793		if (copy_from_user(&zone, argp, sizeof(zone)))
2794			goto out;
2795		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2796		break;
2797	}
2798	case KVM_UNREGISTER_COALESCED_MMIO: {
2799		struct kvm_coalesced_mmio_zone zone;
2800
2801		r = -EFAULT;
2802		if (copy_from_user(&zone, argp, sizeof(zone)))
2803			goto out;
2804		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2805		break;
2806	}
2807#endif
2808	case KVM_IRQFD: {
2809		struct kvm_irqfd data;
2810
2811		r = -EFAULT;
2812		if (copy_from_user(&data, argp, sizeof(data)))
2813			goto out;
2814		r = kvm_irqfd(kvm, &data);
2815		break;
2816	}
2817	case KVM_IOEVENTFD: {
2818		struct kvm_ioeventfd data;
2819
2820		r = -EFAULT;
2821		if (copy_from_user(&data, argp, sizeof(data)))
2822			goto out;
2823		r = kvm_ioeventfd(kvm, &data);
2824		break;
2825	}
2826#ifdef CONFIG_HAVE_KVM_MSI
2827	case KVM_SIGNAL_MSI: {
2828		struct kvm_msi msi;
2829
2830		r = -EFAULT;
2831		if (copy_from_user(&msi, argp, sizeof(msi)))
2832			goto out;
2833		r = kvm_send_userspace_msi(kvm, &msi);
2834		break;
2835	}
2836#endif
2837#ifdef __KVM_HAVE_IRQ_LINE
2838	case KVM_IRQ_LINE_STATUS:
2839	case KVM_IRQ_LINE: {
2840		struct kvm_irq_level irq_event;
2841
2842		r = -EFAULT;
2843		if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
2844			goto out;
2845
2846		r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2847					ioctl == KVM_IRQ_LINE_STATUS);
2848		if (r)
2849			goto out;
2850
2851		r = -EFAULT;
2852		if (ioctl == KVM_IRQ_LINE_STATUS) {
2853			if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
2854				goto out;
2855		}
2856
2857		r = 0;
2858		break;
2859	}
2860#endif
2861#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2862	case KVM_SET_GSI_ROUTING: {
2863		struct kvm_irq_routing routing;
2864		struct kvm_irq_routing __user *urouting;
2865		struct kvm_irq_routing_entry *entries;
2866
2867		r = -EFAULT;
2868		if (copy_from_user(&routing, argp, sizeof(routing)))
2869			goto out;
2870		r = -EINVAL;
2871		if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2872			goto out;
2873		if (routing.flags)
2874			goto out;
2875		r = -ENOMEM;
2876		entries = vmalloc(routing.nr * sizeof(*entries));
2877		if (!entries)
2878			goto out;
2879		r = -EFAULT;
2880		urouting = argp;
2881		if (copy_from_user(entries, urouting->entries,
2882				   routing.nr * sizeof(*entries)))
2883			goto out_free_irq_routing;
 
 
 
 
 
2884		r = kvm_set_irq_routing(kvm, entries, routing.nr,
2885					routing.flags);
2886out_free_irq_routing:
2887		vfree(entries);
2888		break;
2889	}
2890#endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2891	case KVM_CREATE_DEVICE: {
2892		struct kvm_create_device cd;
2893
2894		r = -EFAULT;
2895		if (copy_from_user(&cd, argp, sizeof(cd)))
2896			goto out;
2897
2898		r = kvm_ioctl_create_device(kvm, &cd);
2899		if (r)
2900			goto out;
2901
2902		r = -EFAULT;
2903		if (copy_to_user(argp, &cd, sizeof(cd)))
2904			goto out;
2905
2906		r = 0;
2907		break;
2908	}
2909	case KVM_CHECK_EXTENSION:
2910		r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
2911		break;
 
 
 
 
 
 
2912	default:
2913		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2914	}
2915out:
2916	return r;
2917}
2918
2919#ifdef CONFIG_KVM_COMPAT
2920struct compat_kvm_dirty_log {
2921	__u32 slot;
2922	__u32 padding1;
2923	union {
2924		compat_uptr_t dirty_bitmap; /* one bit per page */
2925		__u64 padding2;
2926	};
2927};
2928
 
 
 
 
 
 
 
 
 
 
2929static long kvm_vm_compat_ioctl(struct file *filp,
2930			   unsigned int ioctl, unsigned long arg)
2931{
2932	struct kvm *kvm = filp->private_data;
2933	int r;
2934
2935	if (kvm->mm != current->mm)
2936		return -EIO;
2937	switch (ioctl) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2938	case KVM_GET_DIRTY_LOG: {
2939		struct compat_kvm_dirty_log compat_log;
2940		struct kvm_dirty_log log;
2941
2942		r = -EFAULT;
2943		if (copy_from_user(&compat_log, (void __user *)arg,
2944				   sizeof(compat_log)))
2945			goto out;
2946		log.slot	 = compat_log.slot;
2947		log.padding1	 = compat_log.padding1;
2948		log.padding2	 = compat_log.padding2;
2949		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2950
2951		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2952		break;
2953	}
2954	default:
2955		r = kvm_vm_ioctl(filp, ioctl, arg);
2956	}
2957
2958out:
2959	return r;
2960}
2961#endif
2962
2963static struct file_operations kvm_vm_fops = {
2964	.release        = kvm_vm_release,
2965	.unlocked_ioctl = kvm_vm_ioctl,
2966#ifdef CONFIG_KVM_COMPAT
2967	.compat_ioctl   = kvm_vm_compat_ioctl,
2968#endif
2969	.llseek		= noop_llseek,
 
2970};
2971
 
 
 
 
 
 
2972static int kvm_dev_ioctl_create_vm(unsigned long type)
2973{
2974	int r;
2975	struct kvm *kvm;
 
2976
2977	kvm = kvm_create_vm(type);
2978	if (IS_ERR(kvm))
2979		return PTR_ERR(kvm);
2980#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2981	r = kvm_coalesced_mmio_init(kvm);
2982	if (r < 0) {
2983		kvm_put_kvm(kvm);
2984		return r;
2985	}
2986#endif
2987	r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
2988	if (r < 0)
2989		kvm_put_kvm(kvm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2990
 
 
2991	return r;
2992}
2993
2994static long kvm_dev_ioctl(struct file *filp,
2995			  unsigned int ioctl, unsigned long arg)
2996{
2997	long r = -EINVAL;
2998
2999	switch (ioctl) {
3000	case KVM_GET_API_VERSION:
3001		if (arg)
3002			goto out;
3003		r = KVM_API_VERSION;
3004		break;
3005	case KVM_CREATE_VM:
3006		r = kvm_dev_ioctl_create_vm(arg);
3007		break;
3008	case KVM_CHECK_EXTENSION:
3009		r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
3010		break;
3011	case KVM_GET_VCPU_MMAP_SIZE:
3012		if (arg)
3013			goto out;
3014		r = PAGE_SIZE;     /* struct kvm_run */
3015#ifdef CONFIG_X86
3016		r += PAGE_SIZE;    /* pio data page */
3017#endif
3018#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
3019		r += PAGE_SIZE;    /* coalesced mmio ring page */
3020#endif
3021		break;
3022	case KVM_TRACE_ENABLE:
3023	case KVM_TRACE_PAUSE:
3024	case KVM_TRACE_DISABLE:
3025		r = -EOPNOTSUPP;
3026		break;
3027	default:
3028		return kvm_arch_dev_ioctl(filp, ioctl, arg);
3029	}
3030out:
3031	return r;
3032}
3033
3034static struct file_operations kvm_chardev_ops = {
3035	.unlocked_ioctl = kvm_dev_ioctl,
3036	.compat_ioctl   = kvm_dev_ioctl,
3037	.llseek		= noop_llseek,
 
3038};
3039
3040static struct miscdevice kvm_dev = {
3041	KVM_MINOR,
3042	"kvm",
3043	&kvm_chardev_ops,
3044};
3045
3046static void hardware_enable_nolock(void *junk)
3047{
3048	int cpu = raw_smp_processor_id();
3049	int r;
3050
3051	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
3052		return;
3053
3054	cpumask_set_cpu(cpu, cpus_hardware_enabled);
3055
3056	r = kvm_arch_hardware_enable();
3057
3058	if (r) {
3059		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3060		atomic_inc(&hardware_enable_failed);
3061		pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
3062	}
3063}
3064
3065static void hardware_enable(void)
3066{
3067	raw_spin_lock(&kvm_count_lock);
3068	if (kvm_usage_count)
3069		hardware_enable_nolock(NULL);
3070	raw_spin_unlock(&kvm_count_lock);
 
3071}
3072
3073static void hardware_disable_nolock(void *junk)
3074{
3075	int cpu = raw_smp_processor_id();
3076
3077	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
3078		return;
3079	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3080	kvm_arch_hardware_disable();
3081}
3082
3083static void hardware_disable(void)
3084{
3085	raw_spin_lock(&kvm_count_lock);
3086	if (kvm_usage_count)
3087		hardware_disable_nolock(NULL);
3088	raw_spin_unlock(&kvm_count_lock);
 
3089}
3090
3091static void hardware_disable_all_nolock(void)
3092{
3093	BUG_ON(!kvm_usage_count);
3094
3095	kvm_usage_count--;
3096	if (!kvm_usage_count)
3097		on_each_cpu(hardware_disable_nolock, NULL, 1);
3098}
3099
3100static void hardware_disable_all(void)
3101{
3102	raw_spin_lock(&kvm_count_lock);
3103	hardware_disable_all_nolock();
3104	raw_spin_unlock(&kvm_count_lock);
3105}
3106
3107static int hardware_enable_all(void)
3108{
3109	int r = 0;
3110
3111	raw_spin_lock(&kvm_count_lock);
3112
3113	kvm_usage_count++;
3114	if (kvm_usage_count == 1) {
3115		atomic_set(&hardware_enable_failed, 0);
3116		on_each_cpu(hardware_enable_nolock, NULL, 1);
3117
3118		if (atomic_read(&hardware_enable_failed)) {
3119			hardware_disable_all_nolock();
3120			r = -EBUSY;
3121		}
3122	}
3123
3124	raw_spin_unlock(&kvm_count_lock);
3125
3126	return r;
3127}
3128
3129static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
3130			   void *v)
3131{
3132	val &= ~CPU_TASKS_FROZEN;
3133	switch (val) {
3134	case CPU_DYING:
3135		hardware_disable();
3136		break;
3137	case CPU_STARTING:
3138		hardware_enable();
3139		break;
3140	}
3141	return NOTIFY_OK;
3142}
3143
3144static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
3145		      void *v)
3146{
3147	/*
3148	 * Some (well, at least mine) BIOSes hang on reboot if
3149	 * in vmx root mode.
3150	 *
3151	 * And Intel TXT required VMX off for all cpu when system shutdown.
3152	 */
3153	pr_info("kvm: exiting hardware virtualization\n");
3154	kvm_rebooting = true;
3155	on_each_cpu(hardware_disable_nolock, NULL, 1);
3156	return NOTIFY_OK;
3157}
3158
3159static struct notifier_block kvm_reboot_notifier = {
3160	.notifier_call = kvm_reboot,
3161	.priority = 0,
3162};
3163
3164static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
3165{
3166	int i;
3167
3168	for (i = 0; i < bus->dev_count; i++) {
3169		struct kvm_io_device *pos = bus->range[i].dev;
3170
3171		kvm_iodevice_destructor(pos);
3172	}
3173	kfree(bus);
3174}
3175
3176static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
3177				 const struct kvm_io_range *r2)
3178{
3179	gpa_t addr1 = r1->addr;
3180	gpa_t addr2 = r2->addr;
3181
3182	if (addr1 < addr2)
3183		return -1;
3184
3185	/* If r2->len == 0, match the exact address.  If r2->len != 0,
3186	 * accept any overlapping write.  Any order is acceptable for
3187	 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
3188	 * we process all of them.
3189	 */
3190	if (r2->len) {
3191		addr1 += r1->len;
3192		addr2 += r2->len;
3193	}
3194
3195	if (addr1 > addr2)
3196		return 1;
3197
3198	return 0;
3199}
3200
3201static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
3202{
3203	return kvm_io_bus_cmp(p1, p2);
3204}
3205
3206static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
3207			  gpa_t addr, int len)
3208{
3209	bus->range[bus->dev_count++] = (struct kvm_io_range) {
3210		.addr = addr,
3211		.len = len,
3212		.dev = dev,
3213	};
3214
3215	sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
3216		kvm_io_bus_sort_cmp, NULL);
3217
3218	return 0;
3219}
3220
3221static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
3222			     gpa_t addr, int len)
3223{
3224	struct kvm_io_range *range, key;
3225	int off;
3226
3227	key = (struct kvm_io_range) {
3228		.addr = addr,
3229		.len = len,
3230	};
3231
3232	range = bsearch(&key, bus->range, bus->dev_count,
3233			sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
3234	if (range == NULL)
3235		return -ENOENT;
3236
3237	off = range - bus->range;
3238
3239	while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
3240		off--;
3241
3242	return off;
3243}
3244
3245static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
3246			      struct kvm_io_range *range, const void *val)
3247{
3248	int idx;
3249
3250	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3251	if (idx < 0)
3252		return -EOPNOTSUPP;
3253
3254	while (idx < bus->dev_count &&
3255		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3256		if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
3257					range->len, val))
3258			return idx;
3259		idx++;
3260	}
3261
3262	return -EOPNOTSUPP;
3263}
3264
3265/* kvm_io_bus_write - called under kvm->slots_lock */
3266int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3267		     int len, const void *val)
3268{
3269	struct kvm_io_bus *bus;
3270	struct kvm_io_range range;
3271	int r;
3272
3273	range = (struct kvm_io_range) {
3274		.addr = addr,
3275		.len = len,
3276	};
3277
3278	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
 
 
3279	r = __kvm_io_bus_write(vcpu, bus, &range, val);
3280	return r < 0 ? r : 0;
3281}
 
3282
3283/* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3284int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
3285			    gpa_t addr, int len, const void *val, long cookie)
3286{
3287	struct kvm_io_bus *bus;
3288	struct kvm_io_range range;
3289
3290	range = (struct kvm_io_range) {
3291		.addr = addr,
3292		.len = len,
3293	};
3294
3295	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
 
 
3296
3297	/* First try the device referenced by cookie. */
3298	if ((cookie >= 0) && (cookie < bus->dev_count) &&
3299	    (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
3300		if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
3301					val))
3302			return cookie;
3303
3304	/*
3305	 * cookie contained garbage; fall back to search and return the
3306	 * correct cookie value.
3307	 */
3308	return __kvm_io_bus_write(vcpu, bus, &range, val);
3309}
3310
3311static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
3312			     struct kvm_io_range *range, void *val)
3313{
3314	int idx;
3315
3316	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3317	if (idx < 0)
3318		return -EOPNOTSUPP;
3319
3320	while (idx < bus->dev_count &&
3321		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3322		if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
3323				       range->len, val))
3324			return idx;
3325		idx++;
3326	}
3327
3328	return -EOPNOTSUPP;
3329}
3330EXPORT_SYMBOL_GPL(kvm_io_bus_write);
3331
3332/* kvm_io_bus_read - called under kvm->slots_lock */
3333int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3334		    int len, void *val)
3335{
3336	struct kvm_io_bus *bus;
3337	struct kvm_io_range range;
3338	int r;
3339
3340	range = (struct kvm_io_range) {
3341		.addr = addr,
3342		.len = len,
3343	};
3344
3345	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
 
 
3346	r = __kvm_io_bus_read(vcpu, bus, &range, val);
3347	return r < 0 ? r : 0;
3348}
3349
3350
3351/* Caller must hold slots_lock. */
3352int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
3353			    int len, struct kvm_io_device *dev)
3354{
 
3355	struct kvm_io_bus *new_bus, *bus;
 
 
 
 
 
3356
3357	bus = kvm->buses[bus_idx];
3358	/* exclude ioeventfd which is limited by maximum fd */
3359	if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3360		return -ENOSPC;
3361
3362	new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3363			  sizeof(struct kvm_io_range)), GFP_KERNEL);
3364	if (!new_bus)
3365		return -ENOMEM;
3366	memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
3367	       sizeof(struct kvm_io_range)));
3368	kvm_io_bus_insert_dev(new_bus, dev, addr, len);
 
 
 
 
 
 
 
 
 
 
 
 
 
3369	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3370	synchronize_srcu_expedited(&kvm->srcu);
3371	kfree(bus);
3372
3373	return 0;
3374}
3375
3376/* Caller must hold slots_lock. */
3377int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
3378			      struct kvm_io_device *dev)
3379{
3380	int i, r;
3381	struct kvm_io_bus *new_bus, *bus;
3382
3383	bus = kvm->buses[bus_idx];
3384	r = -ENOENT;
3385	for (i = 0; i < bus->dev_count; i++)
 
 
 
 
3386		if (bus->range[i].dev == dev) {
3387			r = 0;
3388			break;
3389		}
 
3390
3391	if (r)
3392		return r;
3393
3394	new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3395			  sizeof(struct kvm_io_range)), GFP_KERNEL);
3396	if (!new_bus)
3397		return -ENOMEM;
3398
3399	memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
3400	new_bus->dev_count--;
3401	memcpy(new_bus->range + i, bus->range + i + 1,
3402	       (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
 
 
 
 
3403
3404	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3405	synchronize_srcu_expedited(&kvm->srcu);
 
 
 
 
 
 
 
 
 
 
 
3406	kfree(bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3407	return r;
3408}
3409
3410static struct notifier_block kvm_cpu_notifier = {
3411	.notifier_call = kvm_cpu_hotplug,
 
 
 
 
 
 
 
 
 
 
 
 
3412};
3413
3414static int vm_stat_get(void *_offset, u64 *val)
3415{
3416	unsigned offset = (long)_offset;
3417	struct kvm *kvm;
 
3418
3419	*val = 0;
3420	spin_lock(&kvm_lock);
3421	list_for_each_entry(kvm, &vm_list, vm_list)
3422		*val += *(u32 *)((void *)kvm + offset);
3423	spin_unlock(&kvm_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3424	return 0;
3425}
3426
3427DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
 
3428
3429static int vcpu_stat_get(void *_offset, u64 *val)
3430{
3431	unsigned offset = (long)_offset;
3432	struct kvm *kvm;
3433	struct kvm_vcpu *vcpu;
3434	int i;
3435
3436	*val = 0;
3437	spin_lock(&kvm_lock);
3438	list_for_each_entry(kvm, &vm_list, vm_list)
3439		kvm_for_each_vcpu(i, vcpu, kvm)
3440			*val += *(u32 *)((void *)vcpu + offset);
3441
3442	spin_unlock(&kvm_lock);
3443	return 0;
3444}
3445
3446DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
 
 
 
3447
3448static const struct file_operations *stat_fops[] = {
3449	[KVM_STAT_VCPU] = &vcpu_stat_fops,
3450	[KVM_STAT_VM]   = &vm_stat_fops,
3451};
 
 
 
 
 
 
 
3452
3453static int kvm_init_debug(void)
 
 
 
 
3454{
3455	int r = -EEXIST;
3456	struct kvm_stats_debugfs_item *p;
3457
3458	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3459	if (kvm_debugfs_dir == NULL)
3460		goto out;
 
 
 
 
 
 
 
 
 
 
3461
3462	for (p = debugfs_entries; p->name; ++p) {
3463		if (!debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3464					 (void *)(long)p->offset,
3465					 stat_fops[p->kind]))
3466			goto out_dir;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3467	}
 
 
 
 
 
3468
3469	return 0;
 
 
 
 
3470
3471out_dir:
3472	debugfs_remove_recursive(kvm_debugfs_dir);
3473out:
3474	return r;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3475}
3476
3477static int kvm_suspend(void)
3478{
3479	if (kvm_usage_count)
3480		hardware_disable_nolock(NULL);
3481	return 0;
3482}
3483
3484static void kvm_resume(void)
3485{
3486	if (kvm_usage_count) {
3487		WARN_ON(raw_spin_is_locked(&kvm_count_lock));
 
 
3488		hardware_enable_nolock(NULL);
3489	}
3490}
3491
3492static struct syscore_ops kvm_syscore_ops = {
3493	.suspend = kvm_suspend,
3494	.resume = kvm_resume,
3495};
3496
3497static inline
3498struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3499{
3500	return container_of(pn, struct kvm_vcpu, preempt_notifier);
3501}
3502
3503static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3504{
3505	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3506
3507	if (vcpu->preempted)
3508		vcpu->preempted = false;
3509
 
3510	kvm_arch_sched_in(vcpu, cpu);
3511
3512	kvm_arch_vcpu_load(vcpu, cpu);
3513}
3514
3515static void kvm_sched_out(struct preempt_notifier *pn,
3516			  struct task_struct *next)
3517{
3518	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3519
3520	if (current->state == TASK_RUNNING)
3521		vcpu->preempted = true;
 
 
3522	kvm_arch_vcpu_put(vcpu);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3523}
3524
3525int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3526		  struct module *module)
3527{
 
3528	int r;
3529	int cpu;
3530
3531	r = kvm_arch_init(opaque);
3532	if (r)
3533		goto out_fail;
3534
3535	/*
3536	 * kvm_arch_init makes sure there's at most one caller
3537	 * for architectures that support multiple implementations,
3538	 * like intel and amd on x86.
3539	 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3540	 * conflicts in case kvm is already setup for another implementation.
3541	 */
3542	r = kvm_irqfd_init();
3543	if (r)
3544		goto out_irqfd;
3545
3546	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3547		r = -ENOMEM;
3548		goto out_free_0;
3549	}
3550
3551	r = kvm_arch_hardware_setup();
3552	if (r < 0)
3553		goto out_free_0a;
3554
 
 
3555	for_each_online_cpu(cpu) {
3556		smp_call_function_single(cpu,
3557				kvm_arch_check_processor_compat,
3558				&r, 1);
3559		if (r < 0)
3560			goto out_free_1;
3561	}
3562
3563	r = register_cpu_notifier(&kvm_cpu_notifier);
 
3564	if (r)
3565		goto out_free_2;
3566	register_reboot_notifier(&kvm_reboot_notifier);
3567
3568	/* A kmem cache lets us meet the alignment requirements of fx_save. */
3569	if (!vcpu_align)
3570		vcpu_align = __alignof__(struct kvm_vcpu);
3571	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3572					   0, NULL);
 
 
 
 
 
3573	if (!kvm_vcpu_cache) {
3574		r = -ENOMEM;
3575		goto out_free_3;
3576	}
3577
3578	r = kvm_async_pf_init();
3579	if (r)
3580		goto out_free;
3581
3582	kvm_chardev_ops.owner = module;
3583	kvm_vm_fops.owner = module;
3584	kvm_vcpu_fops.owner = module;
3585
3586	r = misc_register(&kvm_dev);
3587	if (r) {
3588		pr_err("kvm: misc device register failed\n");
3589		goto out_unreg;
3590	}
3591
3592	register_syscore_ops(&kvm_syscore_ops);
3593
3594	kvm_preempt_ops.sched_in = kvm_sched_in;
3595	kvm_preempt_ops.sched_out = kvm_sched_out;
3596
3597	r = kvm_init_debug();
3598	if (r) {
3599		pr_err("kvm: create debugfs files failed\n");
3600		goto out_undebugfs;
3601	}
3602
3603	r = kvm_vfio_ops_init();
3604	WARN_ON(r);
3605
3606	return 0;
3607
3608out_undebugfs:
3609	unregister_syscore_ops(&kvm_syscore_ops);
3610	misc_deregister(&kvm_dev);
3611out_unreg:
3612	kvm_async_pf_deinit();
3613out_free:
3614	kmem_cache_destroy(kvm_vcpu_cache);
3615out_free_3:
3616	unregister_reboot_notifier(&kvm_reboot_notifier);
3617	unregister_cpu_notifier(&kvm_cpu_notifier);
3618out_free_2:
3619out_free_1:
3620	kvm_arch_hardware_unsetup();
3621out_free_0a:
3622	free_cpumask_var(cpus_hardware_enabled);
3623out_free_0:
3624	kvm_irqfd_exit();
3625out_irqfd:
3626	kvm_arch_exit();
3627out_fail:
3628	return r;
3629}
3630EXPORT_SYMBOL_GPL(kvm_init);
3631
3632void kvm_exit(void)
3633{
3634	debugfs_remove_recursive(kvm_debugfs_dir);
3635	misc_deregister(&kvm_dev);
3636	kmem_cache_destroy(kvm_vcpu_cache);
3637	kvm_async_pf_deinit();
3638	unregister_syscore_ops(&kvm_syscore_ops);
3639	unregister_reboot_notifier(&kvm_reboot_notifier);
3640	unregister_cpu_notifier(&kvm_cpu_notifier);
3641	on_each_cpu(hardware_disable_nolock, NULL, 1);
3642	kvm_arch_hardware_unsetup();
3643	kvm_arch_exit();
3644	kvm_irqfd_exit();
3645	free_cpumask_var(cpus_hardware_enabled);
3646	kvm_vfio_ops_exit();
3647}
3648EXPORT_SYMBOL_GPL(kvm_exit);
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Kernel-based Virtual Machine driver for Linux
   4 *
   5 * This module enables machines with Intel VT-x extensions to run virtual
   6 * machines without emulation or binary translation.
   7 *
   8 * Copyright (C) 2006 Qumranet, Inc.
   9 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  10 *
  11 * Authors:
  12 *   Avi Kivity   <avi@qumranet.com>
  13 *   Yaniv Kamay  <yaniv@qumranet.com>
 
 
 
 
  14 */
  15
  16#include <kvm/iodev.h>
  17
  18#include <linux/kvm_host.h>
  19#include <linux/kvm.h>
  20#include <linux/module.h>
  21#include <linux/errno.h>
  22#include <linux/percpu.h>
  23#include <linux/mm.h>
  24#include <linux/miscdevice.h>
  25#include <linux/vmalloc.h>
  26#include <linux/reboot.h>
  27#include <linux/debugfs.h>
  28#include <linux/highmem.h>
  29#include <linux/file.h>
  30#include <linux/syscore_ops.h>
  31#include <linux/cpu.h>
  32#include <linux/sched/signal.h>
  33#include <linux/sched/mm.h>
  34#include <linux/sched/stat.h>
  35#include <linux/cpumask.h>
  36#include <linux/smp.h>
  37#include <linux/anon_inodes.h>
  38#include <linux/profile.h>
  39#include <linux/kvm_para.h>
  40#include <linux/pagemap.h>
  41#include <linux/mman.h>
  42#include <linux/swap.h>
  43#include <linux/bitops.h>
  44#include <linux/spinlock.h>
  45#include <linux/compat.h>
  46#include <linux/srcu.h>
  47#include <linux/hugetlb.h>
  48#include <linux/slab.h>
  49#include <linux/sort.h>
  50#include <linux/bsearch.h>
  51#include <linux/io.h>
  52#include <linux/lockdep.h>
  53#include <linux/kthread.h>
  54#include <linux/suspend.h>
  55
  56#include <asm/processor.h>
 
  57#include <asm/ioctl.h>
  58#include <linux/uaccess.h>
 
  59
  60#include "coalesced_mmio.h"
  61#include "async_pf.h"
  62#include "mmu_lock.h"
  63#include "vfio.h"
  64
  65#define CREATE_TRACE_POINTS
  66#include <trace/events/kvm.h>
  67
  68#include <linux/kvm_dirty_ring.h>
  69
  70/* Worst case buffer size needed for holding an integer. */
  71#define ITOA_MAX_LEN 12
  72
  73MODULE_AUTHOR("Qumranet");
  74MODULE_LICENSE("GPL");
  75
  76/* Architectures should define their poll value according to the halt latency */
  77unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
  78module_param(halt_poll_ns, uint, 0644);
  79EXPORT_SYMBOL_GPL(halt_poll_ns);
  80
  81/* Default doubles per-vcpu halt_poll_ns. */
  82unsigned int halt_poll_ns_grow = 2;
  83module_param(halt_poll_ns_grow, uint, 0644);
  84EXPORT_SYMBOL_GPL(halt_poll_ns_grow);
  85
  86/* The start value to grow halt_poll_ns from */
  87unsigned int halt_poll_ns_grow_start = 10000; /* 10us */
  88module_param(halt_poll_ns_grow_start, uint, 0644);
  89EXPORT_SYMBOL_GPL(halt_poll_ns_grow_start);
  90
  91/* Default resets per-vcpu halt_poll_ns . */
  92unsigned int halt_poll_ns_shrink;
  93module_param(halt_poll_ns_shrink, uint, 0644);
  94EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
  95
  96/*
  97 * Ordering of locks:
  98 *
  99 *	kvm->lock --> kvm->slots_lock --> kvm->irq_lock
 100 */
 101
 102DEFINE_MUTEX(kvm_lock);
 103static DEFINE_RAW_SPINLOCK(kvm_count_lock);
 104LIST_HEAD(vm_list);
 105
 106static cpumask_var_t cpus_hardware_enabled;
 107static int kvm_usage_count;
 108static atomic_t hardware_enable_failed;
 109
 110static struct kmem_cache *kvm_vcpu_cache;
 
 111
 112static __read_mostly struct preempt_ops kvm_preempt_ops;
 113static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_running_vcpu);
 114
 115struct dentry *kvm_debugfs_dir;
 116EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
 117
 118static const struct file_operations stat_fops_per_vm;
 119
 120static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
 121			   unsigned long arg);
 122#ifdef CONFIG_KVM_COMPAT
 123static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
 124				  unsigned long arg);
 125#define KVM_COMPAT(c)	.compat_ioctl	= (c)
 126#else
 127/*
 128 * For architectures that don't implement a compat infrastructure,
 129 * adopt a double line of defense:
 130 * - Prevent a compat task from opening /dev/kvm
 131 * - If the open has been done by a 64bit task, and the KVM fd
 132 *   passed to a compat task, let the ioctls fail.
 133 */
 134static long kvm_no_compat_ioctl(struct file *file, unsigned int ioctl,
 135				unsigned long arg) { return -EINVAL; }
 136
 137static int kvm_no_compat_open(struct inode *inode, struct file *file)
 138{
 139	return is_compat_task() ? -ENODEV : 0;
 140}
 141#define KVM_COMPAT(c)	.compat_ioctl	= kvm_no_compat_ioctl,	\
 142			.open		= kvm_no_compat_open
 143#endif
 144static int hardware_enable_all(void);
 145static void hardware_disable_all(void);
 146
 147static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
 148
 
 
 
 149__visible bool kvm_rebooting;
 150EXPORT_SYMBOL_GPL(kvm_rebooting);
 151
 152#define KVM_EVENT_CREATE_VM 0
 153#define KVM_EVENT_DESTROY_VM 1
 154static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm);
 155static unsigned long long kvm_createvm_count;
 156static unsigned long long kvm_active_vms;
 157
 158__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
 159						   unsigned long start, unsigned long end)
 160{
 161}
 162
 163bool kvm_is_zone_device_pfn(kvm_pfn_t pfn)
 164{
 165	/*
 166	 * The metadata used by is_zone_device_page() to determine whether or
 167	 * not a page is ZONE_DEVICE is guaranteed to be valid if and only if
 168	 * the device has been pinned, e.g. by get_user_pages().  WARN if the
 169	 * page_count() is zero to help detect bad usage of this helper.
 170	 */
 171	if (!pfn_valid(pfn) || WARN_ON_ONCE(!page_count(pfn_to_page(pfn))))
 172		return false;
 173
 174	return is_zone_device_page(pfn_to_page(pfn));
 175}
 176
 177bool kvm_is_reserved_pfn(kvm_pfn_t pfn)
 178{
 179	/*
 180	 * ZONE_DEVICE pages currently set PG_reserved, but from a refcounting
 181	 * perspective they are "normal" pages, albeit with slightly different
 182	 * usage rules.
 183	 */
 184	if (pfn_valid(pfn))
 185		return PageReserved(pfn_to_page(pfn)) &&
 186		       !is_zero_pfn(pfn) &&
 187		       !kvm_is_zone_device_pfn(pfn);
 188
 189	return true;
 190}
 191
 192bool kvm_is_transparent_hugepage(kvm_pfn_t pfn)
 193{
 194	struct page *page = pfn_to_page(pfn);
 195
 196	if (!PageTransCompoundMap(page))
 197		return false;
 198
 199	return is_transparent_hugepage(compound_head(page));
 200}
 201
 202/*
 203 * Switches to specified vcpu, until a matching vcpu_put()
 204 */
 205void vcpu_load(struct kvm_vcpu *vcpu)
 206{
 207	int cpu = get_cpu();
 208
 209	__this_cpu_write(kvm_running_vcpu, vcpu);
 
 
 210	preempt_notifier_register(&vcpu->preempt_notifier);
 211	kvm_arch_vcpu_load(vcpu, cpu);
 212	put_cpu();
 
 213}
 214EXPORT_SYMBOL_GPL(vcpu_load);
 215
 216void vcpu_put(struct kvm_vcpu *vcpu)
 217{
 218	preempt_disable();
 219	kvm_arch_vcpu_put(vcpu);
 220	preempt_notifier_unregister(&vcpu->preempt_notifier);
 221	__this_cpu_write(kvm_running_vcpu, NULL);
 222	preempt_enable();
 223}
 224EXPORT_SYMBOL_GPL(vcpu_put);
 225
 226/* TODO: merge with kvm_arch_vcpu_should_kick */
 227static bool kvm_request_needs_ipi(struct kvm_vcpu *vcpu, unsigned req)
 228{
 229	int mode = kvm_vcpu_exiting_guest_mode(vcpu);
 230
 231	/*
 232	 * We need to wait for the VCPU to reenable interrupts and get out of
 233	 * READING_SHADOW_PAGE_TABLES mode.
 234	 */
 235	if (req & KVM_REQUEST_WAIT)
 236		return mode != OUTSIDE_GUEST_MODE;
 237
 238	/*
 239	 * Need to kick a running VCPU, but otherwise there is nothing to do.
 240	 */
 241	return mode == IN_GUEST_MODE;
 242}
 243
 244static void ack_flush(void *_completed)
 245{
 246}
 247
 248static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
 249{
 250	if (unlikely(!cpus))
 251		cpus = cpu_online_mask;
 252
 253	if (cpumask_empty(cpus))
 254		return false;
 255
 256	smp_call_function_many(cpus, ack_flush, NULL, wait);
 257	return true;
 258}
 259
 260bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
 261				 struct kvm_vcpu *except,
 262				 unsigned long *vcpu_bitmap, cpumask_var_t tmp)
 263{
 264	int i, cpu, me;
 
 
 265	struct kvm_vcpu *vcpu;
 266	bool called;
 
 267
 268	me = get_cpu();
 269
 270	kvm_for_each_vcpu(i, vcpu, kvm) {
 271		if ((vcpu_bitmap && !test_bit(i, vcpu_bitmap)) ||
 272		    vcpu == except)
 273			continue;
 274
 275		kvm_make_request(req, vcpu);
 276		cpu = vcpu->cpu;
 277
 278		if (!(req & KVM_REQUEST_NO_WAKEUP) && kvm_vcpu_wake_up(vcpu))
 279			continue;
 280
 281		if (tmp != NULL && cpu != -1 && cpu != me &&
 282		    kvm_request_needs_ipi(vcpu, req))
 283			__cpumask_set_cpu(cpu, tmp);
 284	}
 285
 286	called = kvm_kick_many_cpus(tmp, !!(req & KVM_REQUEST_WAIT));
 
 
 
 
 287	put_cpu();
 288
 289	return called;
 290}
 291
 292bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
 293				      struct kvm_vcpu *except)
 294{
 295	cpumask_var_t cpus;
 296	bool called;
 297
 298	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 299
 300	called = kvm_make_vcpus_request_mask(kvm, req, except, NULL, cpus);
 301
 302	free_cpumask_var(cpus);
 303	return called;
 304}
 305
 306bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 307{
 308	return kvm_make_all_cpus_request_except(kvm, req, NULL);
 309}
 310EXPORT_SYMBOL_GPL(kvm_make_all_cpus_request);
 311
 312#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
 313void kvm_flush_remote_tlbs(struct kvm *kvm)
 314{
 315	/*
 316	 * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
 317	 * kvm_make_all_cpus_request.
 318	 */
 319	long dirty_count = smp_load_acquire(&kvm->tlbs_dirty);
 320
 321	/*
 322	 * We want to publish modifications to the page tables before reading
 323	 * mode. Pairs with a memory barrier in arch-specific code.
 324	 * - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
 325	 * and smp_mb in walk_shadow_page_lockless_begin/end.
 326	 * - powerpc: smp_mb in kvmppc_prepare_to_enter.
 327	 *
 328	 * There is already an smp_mb__after_atomic() before
 329	 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
 330	 * barrier here.
 331	 */
 332	if (!kvm_arch_flush_remote_tlb(kvm)
 333	    || kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 334		++kvm->stat.generic.remote_tlb_flush;
 335	cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 336}
 337EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 338#endif
 339
 340void kvm_reload_remote_mmus(struct kvm *kvm)
 341{
 342	kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 343}
 344
 345#ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE
 346static inline void *mmu_memory_cache_alloc_obj(struct kvm_mmu_memory_cache *mc,
 347					       gfp_t gfp_flags)
 348{
 349	gfp_flags |= mc->gfp_zero;
 350
 351	if (mc->kmem_cache)
 352		return kmem_cache_alloc(mc->kmem_cache, gfp_flags);
 353	else
 354		return (void *)__get_free_page(gfp_flags);
 355}
 356
 357int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min)
 358{
 359	void *obj;
 360
 361	if (mc->nobjs >= min)
 362		return 0;
 363	while (mc->nobjs < ARRAY_SIZE(mc->objects)) {
 364		obj = mmu_memory_cache_alloc_obj(mc, GFP_KERNEL_ACCOUNT);
 365		if (!obj)
 366			return mc->nobjs >= min ? 0 : -ENOMEM;
 367		mc->objects[mc->nobjs++] = obj;
 368	}
 369	return 0;
 370}
 371
 372int kvm_mmu_memory_cache_nr_free_objects(struct kvm_mmu_memory_cache *mc)
 373{
 374	return mc->nobjs;
 375}
 376
 377void kvm_mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
 378{
 379	while (mc->nobjs) {
 380		if (mc->kmem_cache)
 381			kmem_cache_free(mc->kmem_cache, mc->objects[--mc->nobjs]);
 382		else
 383			free_page((unsigned long)mc->objects[--mc->nobjs]);
 384	}
 385}
 386
 387void *kvm_mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
 388{
 389	void *p;
 390
 391	if (WARN_ON(!mc->nobjs))
 392		p = mmu_memory_cache_alloc_obj(mc, GFP_ATOMIC | __GFP_ACCOUNT);
 393	else
 394		p = mc->objects[--mc->nobjs];
 395	BUG_ON(!p);
 396	return p;
 397}
 398#endif
 399
 400static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 401{
 402	mutex_init(&vcpu->mutex);
 403	vcpu->cpu = -1;
 404	vcpu->kvm = kvm;
 405	vcpu->vcpu_id = id;
 406	vcpu->pid = NULL;
 407	rcuwait_init(&vcpu->wait);
 408	kvm_async_pf_vcpu_init(vcpu);
 409
 410	vcpu->pre_pcpu = -1;
 411	INIT_LIST_HEAD(&vcpu->blocked_vcpu_list);
 412
 
 
 
 
 
 
 
 413	kvm_vcpu_set_in_spin_loop(vcpu, false);
 414	kvm_vcpu_set_dy_eligible(vcpu, false);
 415	vcpu->preempted = false;
 416	vcpu->ready = false;
 417	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
 
 
 
 
 
 
 
 418}
 
 419
 420void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
 421{
 422	kvm_dirty_ring_free(&vcpu->dirty_ring);
 423	kvm_arch_vcpu_destroy(vcpu);
 424
 425	/*
 426	 * No need for rcu_read_lock as VCPU_RUN is the only place that changes
 427	 * the vcpu->pid pointer, and at destruction time all file descriptors
 428	 * are already gone.
 429	 */
 430	put_pid(rcu_dereference_protected(vcpu->pid, 1));
 431
 432	free_page((unsigned long)vcpu->run);
 433	kmem_cache_free(kvm_vcpu_cache, vcpu);
 434}
 435EXPORT_SYMBOL_GPL(kvm_vcpu_destroy);
 436
 437#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 438static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 439{
 440	return container_of(mn, struct kvm, mmu_notifier);
 441}
 442
 443static void kvm_mmu_notifier_invalidate_range(struct mmu_notifier *mn,
 444					      struct mm_struct *mm,
 445					      unsigned long start, unsigned long end)
 446{
 447	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 448	int idx;
 449
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 450	idx = srcu_read_lock(&kvm->srcu);
 451	kvm_arch_mmu_notifier_invalidate_range(kvm, start, end);
 452	srcu_read_unlock(&kvm->srcu, idx);
 453}
 454
 455typedef bool (*hva_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range);
 456
 457typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start,
 458			     unsigned long end);
 459
 460struct kvm_hva_range {
 461	unsigned long start;
 462	unsigned long end;
 463	pte_t pte;
 464	hva_handler_t handler;
 465	on_lock_fn_t on_lock;
 466	bool flush_on_ret;
 467	bool may_block;
 468};
 469
 470/*
 471 * Use a dedicated stub instead of NULL to indicate that there is no callback
 472 * function/handler.  The compiler technically can't guarantee that a real
 473 * function will have a non-zero address, and so it will generate code to
 474 * check for !NULL, whereas comparing against a stub will be elided at compile
 475 * time (unless the compiler is getting long in the tooth, e.g. gcc 4.9).
 476 */
 477static void kvm_null_fn(void)
 478{
 479
 480}
 481#define IS_KVM_NULL_FN(fn) ((fn) == (void *)kvm_null_fn)
 482
 483static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
 484						  const struct kvm_hva_range *range)
 485{
 486	bool ret = false, locked = false;
 487	struct kvm_gfn_range gfn_range;
 488	struct kvm_memory_slot *slot;
 489	struct kvm_memslots *slots;
 490	int i, idx;
 491
 492	/* A null handler is allowed if and only if on_lock() is provided. */
 493	if (WARN_ON_ONCE(IS_KVM_NULL_FN(range->on_lock) &&
 494			 IS_KVM_NULL_FN(range->handler)))
 495		return 0;
 496
 497	idx = srcu_read_lock(&kvm->srcu);
 498
 499	/* The on_lock() path does not yet support lock elision. */
 500	if (!IS_KVM_NULL_FN(range->on_lock)) {
 501		locked = true;
 502		KVM_MMU_LOCK(kvm);
 503
 504		range->on_lock(kvm, range->start, range->end);
 505
 506		if (IS_KVM_NULL_FN(range->handler))
 507			goto out_unlock;
 508	}
 509
 510	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
 511		slots = __kvm_memslots(kvm, i);
 512		kvm_for_each_memslot(slot, slots) {
 513			unsigned long hva_start, hva_end;
 514
 515			hva_start = max(range->start, slot->userspace_addr);
 516			hva_end = min(range->end, slot->userspace_addr +
 517						  (slot->npages << PAGE_SHIFT));
 518			if (hva_start >= hva_end)
 519				continue;
 520
 521			/*
 522			 * To optimize for the likely case where the address
 523			 * range is covered by zero or one memslots, don't
 524			 * bother making these conditional (to avoid writes on
 525			 * the second or later invocation of the handler).
 526			 */
 527			gfn_range.pte = range->pte;
 528			gfn_range.may_block = range->may_block;
 529
 530			/*
 531			 * {gfn(page) | page intersects with [hva_start, hva_end)} =
 532			 * {gfn_start, gfn_start+1, ..., gfn_end-1}.
 533			 */
 534			gfn_range.start = hva_to_gfn_memslot(hva_start, slot);
 535			gfn_range.end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, slot);
 536			gfn_range.slot = slot;
 537
 538			if (!locked) {
 539				locked = true;
 540				KVM_MMU_LOCK(kvm);
 541			}
 542			ret |= range->handler(kvm, &gfn_range);
 543		}
 544	}
 545
 546	if (range->flush_on_ret && (ret || kvm->tlbs_dirty))
 547		kvm_flush_remote_tlbs(kvm);
 548
 549out_unlock:
 550	if (locked)
 551		KVM_MMU_UNLOCK(kvm);
 552
 553	srcu_read_unlock(&kvm->srcu, idx);
 554
 555	/* The notifiers are averse to booleans. :-( */
 556	return (int)ret;
 557}
 558
 559static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn,
 560						unsigned long start,
 561						unsigned long end,
 562						pte_t pte,
 563						hva_handler_t handler)
 564{
 565	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 566	const struct kvm_hva_range range = {
 567		.start		= start,
 568		.end		= end,
 569		.pte		= pte,
 570		.handler	= handler,
 571		.on_lock	= (void *)kvm_null_fn,
 572		.flush_on_ret	= true,
 573		.may_block	= false,
 574	};
 575
 576	return __kvm_handle_hva_range(kvm, &range);
 577}
 578
 579static __always_inline int kvm_handle_hva_range_no_flush(struct mmu_notifier *mn,
 580							 unsigned long start,
 581							 unsigned long end,
 582							 hva_handler_t handler)
 583{
 584	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 585	const struct kvm_hva_range range = {
 586		.start		= start,
 587		.end		= end,
 588		.pte		= __pte(0),
 589		.handler	= handler,
 590		.on_lock	= (void *)kvm_null_fn,
 591		.flush_on_ret	= false,
 592		.may_block	= false,
 593	};
 594
 595	return __kvm_handle_hva_range(kvm, &range);
 596}
 597static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 598					struct mm_struct *mm,
 599					unsigned long address,
 600					pte_t pte)
 601{
 602	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 
 603
 604	trace_kvm_set_spte_hva(address);
 605
 606	/*
 607	 * .change_pte() must be surrounded by .invalidate_range_{start,end}(),
 608	 * and so always runs with an elevated notifier count.  This obviates
 609	 * the need to bump the sequence count.
 610	 */
 611	WARN_ON_ONCE(!kvm->mmu_notifier_count);
 612
 613	kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn);
 614}
 615
 616static void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start,
 617				   unsigned long end)
 
 
 618{
 
 
 
 
 
 619	/*
 620	 * The count increase must become visible at unlock time as no
 621	 * spte can be established without taking the mmu_lock and
 622	 * count is also read inside the mmu_lock critical section.
 623	 */
 624	kvm->mmu_notifier_count++;
 625	if (likely(kvm->mmu_notifier_count == 1)) {
 626		kvm->mmu_notifier_range_start = start;
 627		kvm->mmu_notifier_range_end = end;
 628	} else {
 629		/*
 630		 * Fully tracking multiple concurrent ranges has dimishing
 631		 * returns. Keep things simple and just find the minimal range
 632		 * which includes the current and new ranges. As there won't be
 633		 * enough information to subtract a range after its invalidate
 634		 * completes, any ranges invalidated concurrently will
 635		 * accumulate and persist until all outstanding invalidates
 636		 * complete.
 637		 */
 638		kvm->mmu_notifier_range_start =
 639			min(kvm->mmu_notifier_range_start, start);
 640		kvm->mmu_notifier_range_end =
 641			max(kvm->mmu_notifier_range_end, end);
 642	}
 643}
 644
 645static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 646					const struct mmu_notifier_range *range)
 
 
 647{
 648	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 649	const struct kvm_hva_range hva_range = {
 650		.start		= range->start,
 651		.end		= range->end,
 652		.pte		= __pte(0),
 653		.handler	= kvm_unmap_gfn_range,
 654		.on_lock	= kvm_inc_notifier_count,
 655		.flush_on_ret	= true,
 656		.may_block	= mmu_notifier_range_blockable(range),
 657	};
 658
 659	trace_kvm_unmap_hva_range(range->start, range->end);
 660
 661	__kvm_handle_hva_range(kvm, &hva_range);
 662
 663	return 0;
 664}
 665
 666static void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start,
 667				   unsigned long end)
 668{
 669	/*
 670	 * This sequence increase will notify the kvm page fault that
 671	 * the page that is going to be mapped in the spte could have
 672	 * been freed.
 673	 */
 674	kvm->mmu_notifier_seq++;
 675	smp_wmb();
 676	/*
 677	 * The above sequence increase must be visible before the
 678	 * below count decrease, which is ensured by the smp_wmb above
 679	 * in conjunction with the smp_rmb in mmu_notifier_retry().
 680	 */
 681	kvm->mmu_notifier_count--;
 682}
 683
 684static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 685					const struct mmu_notifier_range *range)
 686{
 687	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 688	const struct kvm_hva_range hva_range = {
 689		.start		= range->start,
 690		.end		= range->end,
 691		.pte		= __pte(0),
 692		.handler	= (void *)kvm_null_fn,
 693		.on_lock	= kvm_dec_notifier_count,
 694		.flush_on_ret	= false,
 695		.may_block	= mmu_notifier_range_blockable(range),
 696	};
 697
 698	__kvm_handle_hva_range(kvm, &hva_range);
 699
 700	BUG_ON(kvm->mmu_notifier_count < 0);
 701}
 702
 703static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 704					      struct mm_struct *mm,
 705					      unsigned long start,
 706					      unsigned long end)
 707{
 708	trace_kvm_age_hva(start, end);
 
 709
 710	return kvm_handle_hva_range(mn, start, end, __pte(0), kvm_age_gfn);
 
 
 
 
 
 
 
 
 
 
 711}
 712
 713static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
 714					struct mm_struct *mm,
 715					unsigned long start,
 716					unsigned long end)
 717{
 718	trace_kvm_age_hva(start, end);
 
 719
 
 
 720	/*
 721	 * Even though we do not flush TLB, this will still adversely
 722	 * affect performance on pre-Haswell Intel EPT, where there is
 723	 * no EPT Access Bit to clear so that we have to tear down EPT
 724	 * tables instead. If we find this unacceptable, we can always
 725	 * add a parameter to kvm_age_hva so that it effectively doesn't
 726	 * do anything on clear_young.
 727	 *
 728	 * Also note that currently we never issue secondary TLB flushes
 729	 * from clear_young, leaving this job up to the regular system
 730	 * cadence. If we find this inaccurate, we might come up with a
 731	 * more sophisticated heuristic later.
 732	 */
 733	return kvm_handle_hva_range_no_flush(mn, start, end, kvm_age_gfn);
 
 
 
 
 734}
 735
 736static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 737				       struct mm_struct *mm,
 738				       unsigned long address)
 739{
 740	trace_kvm_test_age_hva(address);
 
 741
 742	return kvm_handle_hva_range_no_flush(mn, address, address + 1,
 743					     kvm_test_age_gfn);
 
 
 
 
 
 744}
 745
 746static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 747				     struct mm_struct *mm)
 748{
 749	struct kvm *kvm = mmu_notifier_to_kvm(mn);
 750	int idx;
 751
 752	idx = srcu_read_lock(&kvm->srcu);
 753	kvm_arch_flush_shadow_all(kvm);
 754	srcu_read_unlock(&kvm->srcu, idx);
 755}
 756
 757static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 758	.invalidate_range	= kvm_mmu_notifier_invalidate_range,
 759	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
 760	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
 761	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
 762	.clear_young		= kvm_mmu_notifier_clear_young,
 763	.test_young		= kvm_mmu_notifier_test_young,
 764	.change_pte		= kvm_mmu_notifier_change_pte,
 765	.release		= kvm_mmu_notifier_release,
 766};
 767
 768static int kvm_init_mmu_notifier(struct kvm *kvm)
 769{
 770	kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 771	return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 772}
 773
 774#else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 775
 776static int kvm_init_mmu_notifier(struct kvm *kvm)
 777{
 778	return 0;
 779}
 780
 781#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 782
 783#ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
 784static int kvm_pm_notifier_call(struct notifier_block *bl,
 785				unsigned long state,
 786				void *unused)
 787{
 788	struct kvm *kvm = container_of(bl, struct kvm, pm_notifier);
 789
 790	return kvm_arch_pm_notifier(kvm, state);
 791}
 792
 793static void kvm_init_pm_notifier(struct kvm *kvm)
 794{
 795	kvm->pm_notifier.notifier_call = kvm_pm_notifier_call;
 796	/* Suspend KVM before we suspend ftrace, RCU, etc. */
 797	kvm->pm_notifier.priority = INT_MAX;
 798	register_pm_notifier(&kvm->pm_notifier);
 799}
 800
 801static void kvm_destroy_pm_notifier(struct kvm *kvm)
 802{
 803	unregister_pm_notifier(&kvm->pm_notifier);
 804}
 805#else /* !CONFIG_HAVE_KVM_PM_NOTIFIER */
 806static void kvm_init_pm_notifier(struct kvm *kvm)
 807{
 808}
 809
 810static void kvm_destroy_pm_notifier(struct kvm *kvm)
 811{
 812}
 813#endif /* CONFIG_HAVE_KVM_PM_NOTIFIER */
 814
 815static struct kvm_memslots *kvm_alloc_memslots(void)
 816{
 817	int i;
 818	struct kvm_memslots *slots;
 819
 820	slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
 821	if (!slots)
 822		return NULL;
 823
 
 
 
 
 
 824	for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 825		slots->id_to_index[i] = -1;
 826
 827	return slots;
 828}
 829
 830static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 831{
 832	if (!memslot->dirty_bitmap)
 833		return;
 834
 835	kvfree(memslot->dirty_bitmap);
 836	memslot->dirty_bitmap = NULL;
 837}
 838
 839static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
 
 
 
 
 840{
 841	kvm_destroy_dirty_bitmap(slot);
 
 842
 843	kvm_arch_free_memslot(kvm, slot);
 844
 845	slot->flags = 0;
 846	slot->npages = 0;
 847}
 848
 849static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
 850{
 851	struct kvm_memory_slot *memslot;
 852
 853	if (!slots)
 854		return;
 855
 856	kvm_for_each_memslot(memslot, slots)
 857		kvm_free_memslot(kvm, memslot);
 858
 859	kvfree(slots);
 860}
 861
 862static umode_t kvm_stats_debugfs_mode(const struct _kvm_stats_desc *pdesc)
 863{
 864	switch (pdesc->desc.flags & KVM_STATS_TYPE_MASK) {
 865	case KVM_STATS_TYPE_INSTANT:
 866		return 0444;
 867	case KVM_STATS_TYPE_CUMULATIVE:
 868	case KVM_STATS_TYPE_PEAK:
 869	default:
 870		return 0644;
 871	}
 872}
 873
 874
 875static void kvm_destroy_vm_debugfs(struct kvm *kvm)
 876{
 877	int i;
 878	int kvm_debugfs_num_entries = kvm_vm_stats_header.num_desc +
 879				      kvm_vcpu_stats_header.num_desc;
 880
 881	if (!kvm->debugfs_dentry)
 882		return;
 883
 884	debugfs_remove_recursive(kvm->debugfs_dentry);
 885
 886	if (kvm->debugfs_stat_data) {
 887		for (i = 0; i < kvm_debugfs_num_entries; i++)
 888			kfree(kvm->debugfs_stat_data[i]);
 889		kfree(kvm->debugfs_stat_data);
 890	}
 891}
 892
 893static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
 894{
 895	static DEFINE_MUTEX(kvm_debugfs_lock);
 896	struct dentry *dent;
 897	char dir_name[ITOA_MAX_LEN * 2];
 898	struct kvm_stat_data *stat_data;
 899	const struct _kvm_stats_desc *pdesc;
 900	int i;
 901	int kvm_debugfs_num_entries = kvm_vm_stats_header.num_desc +
 902				      kvm_vcpu_stats_header.num_desc;
 903
 904	if (!debugfs_initialized())
 905		return 0;
 906
 907	snprintf(dir_name, sizeof(dir_name), "%d-%d", task_pid_nr(current), fd);
 908	mutex_lock(&kvm_debugfs_lock);
 909	dent = debugfs_lookup(dir_name, kvm_debugfs_dir);
 910	if (dent) {
 911		pr_warn_ratelimited("KVM: debugfs: duplicate directory %s\n", dir_name);
 912		dput(dent);
 913		mutex_unlock(&kvm_debugfs_lock);
 914		return 0;
 915	}
 916	dent = debugfs_create_dir(dir_name, kvm_debugfs_dir);
 917	mutex_unlock(&kvm_debugfs_lock);
 918	if (IS_ERR(dent))
 919		return 0;
 920
 921	kvm->debugfs_dentry = dent;
 922	kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
 923					 sizeof(*kvm->debugfs_stat_data),
 924					 GFP_KERNEL_ACCOUNT);
 925	if (!kvm->debugfs_stat_data)
 926		return -ENOMEM;
 927
 928	for (i = 0; i < kvm_vm_stats_header.num_desc; ++i) {
 929		pdesc = &kvm_vm_stats_desc[i];
 930		stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
 931		if (!stat_data)
 932			return -ENOMEM;
 933
 934		stat_data->kvm = kvm;
 935		stat_data->desc = pdesc;
 936		stat_data->kind = KVM_STAT_VM;
 937		kvm->debugfs_stat_data[i] = stat_data;
 938		debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
 939				    kvm->debugfs_dentry, stat_data,
 940				    &stat_fops_per_vm);
 941	}
 942
 943	for (i = 0; i < kvm_vcpu_stats_header.num_desc; ++i) {
 944		pdesc = &kvm_vcpu_stats_desc[i];
 945		stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
 946		if (!stat_data)
 947			return -ENOMEM;
 948
 949		stat_data->kvm = kvm;
 950		stat_data->desc = pdesc;
 951		stat_data->kind = KVM_STAT_VCPU;
 952		kvm->debugfs_stat_data[i + kvm_vm_stats_header.num_desc] = stat_data;
 953		debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
 954				    kvm->debugfs_dentry, stat_data,
 955				    &stat_fops_per_vm);
 956	}
 957	return 0;
 958}
 959
 960/*
 961 * Called after the VM is otherwise initialized, but just before adding it to
 962 * the vm_list.
 963 */
 964int __weak kvm_arch_post_init_vm(struct kvm *kvm)
 965{
 966	return 0;
 967}
 968
 969/*
 970 * Called just after removing the VM from the vm_list, but before doing any
 971 * other destruction.
 972 */
 973void __weak kvm_arch_pre_destroy_vm(struct kvm *kvm)
 974{
 975}
 976
 977static struct kvm *kvm_create_vm(unsigned long type)
 978{
 
 979	struct kvm *kvm = kvm_arch_alloc_vm();
 980	int r = -ENOMEM;
 981	int i;
 982
 983	if (!kvm)
 984		return ERR_PTR(-ENOMEM);
 985
 986	KVM_MMU_LOCK_INIT(kvm);
 987	mmgrab(current->mm);
 988	kvm->mm = current->mm;
 989	kvm_eventfd_init(kvm);
 990	mutex_init(&kvm->lock);
 991	mutex_init(&kvm->irq_lock);
 992	mutex_init(&kvm->slots_lock);
 993	mutex_init(&kvm->slots_arch_lock);
 994	INIT_LIST_HEAD(&kvm->devices);
 995
 996	BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
 997
 998	if (init_srcu_struct(&kvm->srcu))
 999		goto out_err_no_srcu;
1000	if (init_srcu_struct(&kvm->irq_srcu))
1001		goto out_err_no_irq_srcu;
1002
1003	refcount_set(&kvm->users_count, 1);
1004	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
1005		struct kvm_memslots *slots = kvm_alloc_memslots();
1006
1007		if (!slots)
1008			goto out_err_no_arch_destroy_vm;
1009		/* Generations must be different for each address space. */
1010		slots->generation = i;
1011		rcu_assign_pointer(kvm->memslots[i], slots);
1012	}
1013
1014	for (i = 0; i < KVM_NR_BUSES; i++) {
1015		rcu_assign_pointer(kvm->buses[i],
1016			kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL_ACCOUNT));
1017		if (!kvm->buses[i])
1018			goto out_err_no_arch_destroy_vm;
1019	}
1020
1021	kvm->max_halt_poll_ns = halt_poll_ns;
1022
1023	r = kvm_arch_init_vm(kvm, type);
1024	if (r)
1025		goto out_err_no_arch_destroy_vm;
1026
1027	r = hardware_enable_all();
1028	if (r)
1029		goto out_err_no_disable;
1030
1031#ifdef CONFIG_HAVE_KVM_IRQFD
1032	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
1033#endif
1034
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1035	r = kvm_init_mmu_notifier(kvm);
1036	if (r)
1037		goto out_err_no_mmu_notifier;
1038
1039	r = kvm_arch_post_init_vm(kvm);
1040	if (r)
1041		goto out_err;
1042
1043	mutex_lock(&kvm_lock);
1044	list_add(&kvm->vm_list, &vm_list);
1045	mutex_unlock(&kvm_lock);
1046
1047	preempt_notifier_inc();
1048	kvm_init_pm_notifier(kvm);
1049
1050	return kvm;
1051
1052out_err:
1053#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
1054	if (kvm->mmu_notifier.ops)
1055		mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
1056#endif
1057out_err_no_mmu_notifier:
1058	hardware_disable_all();
1059out_err_no_disable:
1060	kvm_arch_destroy_vm(kvm);
1061out_err_no_arch_destroy_vm:
1062	WARN_ON_ONCE(!refcount_dec_and_test(&kvm->users_count));
1063	for (i = 0; i < KVM_NR_BUSES; i++)
1064		kfree(kvm_get_bus(kvm, i));
1065	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
1066		kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
1067	cleanup_srcu_struct(&kvm->irq_srcu);
1068out_err_no_irq_srcu:
1069	cleanup_srcu_struct(&kvm->srcu);
1070out_err_no_srcu:
1071	kvm_arch_free_vm(kvm);
1072	mmdrop(current->mm);
1073	return ERR_PTR(r);
1074}
1075
 
 
 
 
 
 
 
 
 
 
 
 
1076static void kvm_destroy_devices(struct kvm *kvm)
1077{
1078	struct kvm_device *dev, *tmp;
1079
1080	/*
1081	 * We do not need to take the kvm->lock here, because nobody else
1082	 * has a reference to the struct kvm at this point and therefore
1083	 * cannot access the devices list anyhow.
1084	 */
1085	list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
1086		list_del(&dev->vm_node);
1087		dev->ops->destroy(dev);
1088	}
1089}
1090
1091static void kvm_destroy_vm(struct kvm *kvm)
1092{
1093	int i;
1094	struct mm_struct *mm = kvm->mm;
1095
1096	kvm_destroy_pm_notifier(kvm);
1097	kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
1098	kvm_destroy_vm_debugfs(kvm);
1099	kvm_arch_sync_events(kvm);
1100	mutex_lock(&kvm_lock);
1101	list_del(&kvm->vm_list);
1102	mutex_unlock(&kvm_lock);
1103	kvm_arch_pre_destroy_vm(kvm);
1104
1105	kvm_free_irq_routing(kvm);
1106	for (i = 0; i < KVM_NR_BUSES; i++) {
1107		struct kvm_io_bus *bus = kvm_get_bus(kvm, i);
1108
1109		if (bus)
1110			kvm_io_bus_destroy(bus);
1111		kvm->buses[i] = NULL;
1112	}
1113	kvm_coalesced_mmio_free(kvm);
1114#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
1115	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
1116#else
1117	kvm_arch_flush_shadow_all(kvm);
1118#endif
1119	kvm_arch_destroy_vm(kvm);
1120	kvm_destroy_devices(kvm);
1121	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
1122		kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
1123	cleanup_srcu_struct(&kvm->irq_srcu);
1124	cleanup_srcu_struct(&kvm->srcu);
1125	kvm_arch_free_vm(kvm);
1126	preempt_notifier_dec();
1127	hardware_disable_all();
1128	mmdrop(mm);
1129}
1130
1131void kvm_get_kvm(struct kvm *kvm)
1132{
1133	refcount_inc(&kvm->users_count);
1134}
1135EXPORT_SYMBOL_GPL(kvm_get_kvm);
1136
1137void kvm_put_kvm(struct kvm *kvm)
1138{
1139	if (refcount_dec_and_test(&kvm->users_count))
1140		kvm_destroy_vm(kvm);
1141}
1142EXPORT_SYMBOL_GPL(kvm_put_kvm);
1143
1144/*
1145 * Used to put a reference that was taken on behalf of an object associated
1146 * with a user-visible file descriptor, e.g. a vcpu or device, if installation
1147 * of the new file descriptor fails and the reference cannot be transferred to
1148 * its final owner.  In such cases, the caller is still actively using @kvm and
1149 * will fail miserably if the refcount unexpectedly hits zero.
1150 */
1151void kvm_put_kvm_no_destroy(struct kvm *kvm)
1152{
1153	WARN_ON(refcount_dec_and_test(&kvm->users_count));
1154}
1155EXPORT_SYMBOL_GPL(kvm_put_kvm_no_destroy);
1156
1157static int kvm_vm_release(struct inode *inode, struct file *filp)
1158{
1159	struct kvm *kvm = filp->private_data;
1160
1161	kvm_irqfd_release(kvm);
1162
1163	kvm_put_kvm(kvm);
1164	return 0;
1165}
1166
1167/*
1168 * Allocation size is twice as large as the actual dirty bitmap size.
1169 * See kvm_vm_ioctl_get_dirty_log() why this is needed.
1170 */
1171static int kvm_alloc_dirty_bitmap(struct kvm_memory_slot *memslot)
1172{
1173	unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
1174
1175	memslot->dirty_bitmap = kvzalloc(dirty_bytes, GFP_KERNEL_ACCOUNT);
1176	if (!memslot->dirty_bitmap)
1177		return -ENOMEM;
1178
1179	return 0;
1180}
1181
1182/*
1183 * Delete a memslot by decrementing the number of used slots and shifting all
1184 * other entries in the array forward one spot.
 
 
1185 */
1186static inline void kvm_memslot_delete(struct kvm_memslots *slots,
1187				      struct kvm_memory_slot *memslot)
1188{
 
 
1189	struct kvm_memory_slot *mslots = slots->memslots;
1190	int i;
1191
1192	if (WARN_ON(slots->id_to_index[memslot->id] == -1))
1193		return;
1194
1195	slots->used_slots--;
1196
1197	if (atomic_read(&slots->lru_slot) >= slots->used_slots)
1198		atomic_set(&slots->lru_slot, 0);
1199
1200	for (i = slots->id_to_index[memslot->id]; i < slots->used_slots; i++) {
1201		mslots[i] = mslots[i + 1];
1202		slots->id_to_index[mslots[i].id] = i;
1203	}
1204	mslots[i] = *memslot;
1205	slots->id_to_index[memslot->id] = -1;
1206}
1207
1208/*
1209 * "Insert" a new memslot by incrementing the number of used slots.  Returns
1210 * the new slot's initial index into the memslots array.
1211 */
1212static inline int kvm_memslot_insert_back(struct kvm_memslots *slots)
1213{
1214	return slots->used_slots++;
1215}
1216
1217/*
1218 * Move a changed memslot backwards in the array by shifting existing slots
1219 * with a higher GFN toward the front of the array.  Note, the changed memslot
1220 * itself is not preserved in the array, i.e. not swapped at this time, only
1221 * its new index into the array is tracked.  Returns the changed memslot's
1222 * current index into the memslots array.
1223 */
1224static inline int kvm_memslot_move_backward(struct kvm_memslots *slots,
1225					    struct kvm_memory_slot *memslot)
1226{
1227	struct kvm_memory_slot *mslots = slots->memslots;
1228	int i;
1229
1230	if (WARN_ON_ONCE(slots->id_to_index[memslot->id] == -1) ||
1231	    WARN_ON_ONCE(!slots->used_slots))
1232		return -1;
1233
1234	/*
1235	 * Move the target memslot backward in the array by shifting existing
1236	 * memslots with a higher GFN (than the target memslot) towards the
1237	 * front of the array.
1238	 */
1239	for (i = slots->id_to_index[memslot->id]; i < slots->used_slots - 1; i++) {
1240		if (memslot->base_gfn > mslots[i + 1].base_gfn)
1241			break;
1242
1243		WARN_ON_ONCE(memslot->base_gfn == mslots[i + 1].base_gfn);
1244
1245		/* Shift the next memslot forward one and update its index. */
1246		mslots[i] = mslots[i + 1];
1247		slots->id_to_index[mslots[i].id] = i;
 
1248	}
1249	return i;
1250}
1251
1252/*
1253 * Move a changed memslot forwards in the array by shifting existing slots with
1254 * a lower GFN toward the back of the array.  Note, the changed memslot itself
1255 * is not preserved in the array, i.e. not swapped at this time, only its new
1256 * index into the array is tracked.  Returns the changed memslot's final index
1257 * into the memslots array.
1258 */
1259static inline int kvm_memslot_move_forward(struct kvm_memslots *slots,
1260					   struct kvm_memory_slot *memslot,
1261					   int start)
1262{
1263	struct kvm_memory_slot *mslots = slots->memslots;
1264	int i;
1265
1266	for (i = start; i > 0; i--) {
1267		if (memslot->base_gfn < mslots[i - 1].base_gfn)
1268			break;
1269
1270		WARN_ON_ONCE(memslot->base_gfn == mslots[i - 1].base_gfn);
1271
1272		/* Shift the next memslot back one and update its index. */
1273		mslots[i] = mslots[i - 1];
1274		slots->id_to_index[mslots[i].id] = i;
1275	}
1276	return i;
1277}
1278
1279/*
1280 * Re-sort memslots based on their GFN to account for an added, deleted, or
1281 * moved memslot.  Sorting memslots by GFN allows using a binary search during
1282 * memslot lookup.
1283 *
1284 * IMPORTANT: Slots are sorted from highest GFN to lowest GFN!  I.e. the entry
1285 * at memslots[0] has the highest GFN.
1286 *
1287 * The sorting algorithm takes advantage of having initially sorted memslots
1288 * and knowing the position of the changed memslot.  Sorting is also optimized
1289 * by not swapping the updated memslot and instead only shifting other memslots
1290 * and tracking the new index for the update memslot.  Only once its final
1291 * index is known is the updated memslot copied into its position in the array.
1292 *
1293 *  - When deleting a memslot, the deleted memslot simply needs to be moved to
1294 *    the end of the array.
1295 *
1296 *  - When creating a memslot, the algorithm "inserts" the new memslot at the
1297 *    end of the array and then it forward to its correct location.
1298 *
1299 *  - When moving a memslot, the algorithm first moves the updated memslot
1300 *    backward to handle the scenario where the memslot's GFN was changed to a
1301 *    lower value.  update_memslots() then falls through and runs the same flow
1302 *    as creating a memslot to move the memslot forward to handle the scenario
1303 *    where its GFN was changed to a higher value.
1304 *
1305 * Note, slots are sorted from highest->lowest instead of lowest->highest for
1306 * historical reasons.  Originally, invalid memslots where denoted by having
1307 * GFN=0, thus sorting from highest->lowest naturally sorted invalid memslots
1308 * to the end of the array.  The current algorithm uses dedicated logic to
1309 * delete a memslot and thus does not rely on invalid memslots having GFN=0.
1310 *
1311 * The other historical motiviation for highest->lowest was to improve the
1312 * performance of memslot lookup.  KVM originally used a linear search starting
1313 * at memslots[0].  On x86, the largest memslot usually has one of the highest,
1314 * if not *the* highest, GFN, as the bulk of the guest's RAM is located in a
1315 * single memslot above the 4gb boundary.  As the largest memslot is also the
1316 * most likely to be referenced, sorting it to the front of the array was
1317 * advantageous.  The current binary search starts from the middle of the array
1318 * and uses an LRU pointer to improve performance for all memslots and GFNs.
1319 */
1320static void update_memslots(struct kvm_memslots *slots,
1321			    struct kvm_memory_slot *memslot,
1322			    enum kvm_mr_change change)
1323{
1324	int i;
1325
1326	if (change == KVM_MR_DELETE) {
1327		kvm_memslot_delete(slots, memslot);
1328	} else {
1329		if (change == KVM_MR_CREATE)
1330			i = kvm_memslot_insert_back(slots);
1331		else
1332			i = kvm_memslot_move_backward(slots, memslot);
1333		i = kvm_memslot_move_forward(slots, memslot, i);
1334
1335		/*
1336		 * Copy the memslot to its new position in memslots and update
1337		 * its index accordingly.
1338		 */
1339		slots->memslots[i] = *memslot;
1340		slots->id_to_index[memslot->id] = i;
1341	}
1342}
1343
1344static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
1345{
1346	u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
1347
1348#ifdef __KVM_HAVE_READONLY_MEM
1349	valid_flags |= KVM_MEM_READONLY;
1350#endif
1351
1352	if (mem->flags & ~valid_flags)
1353		return -EINVAL;
1354
1355	return 0;
1356}
1357
1358static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
1359		int as_id, struct kvm_memslots *slots)
1360{
1361	struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
1362	u64 gen = old_memslots->generation;
1363
1364	WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
1365	slots->generation = gen | KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
1366
1367	rcu_assign_pointer(kvm->memslots[as_id], slots);
1368
1369	/*
1370	 * Acquired in kvm_set_memslot. Must be released before synchronize
1371	 * SRCU below in order to avoid deadlock with another thread
1372	 * acquiring the slots_arch_lock in an srcu critical section.
1373	 */
1374	mutex_unlock(&kvm->slots_arch_lock);
 
1375
 
1376	synchronize_srcu_expedited(&kvm->srcu);
1377
1378	/*
1379	 * Increment the new memslot generation a second time, dropping the
1380	 * update in-progress flag and incrementing the generation based on
1381	 * the number of address spaces.  This provides a unique and easily
1382	 * identifiable generation number while the memslots are in flux.
1383	 */
1384	gen = slots->generation & ~KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
1385
1386	/*
1387	 * Generations must be unique even across address spaces.  We do not need
1388	 * a global counter for that, instead the generation space is evenly split
1389	 * across address spaces.  For example, with two address spaces, address
1390	 * space 0 will use generations 0, 2, 4, ... while address space 1 will
1391	 * use generations 1, 3, 5, ...
1392	 */
1393	gen += KVM_ADDRESS_SPACE_NUM;
1394
1395	kvm_arch_memslots_updated(kvm, gen);
1396
1397	slots->generation = gen;
1398
1399	return old_memslots;
1400}
1401
1402static size_t kvm_memslots_size(int slots)
1403{
1404	return sizeof(struct kvm_memslots) +
1405	       (sizeof(struct kvm_memory_slot) * slots);
1406}
1407
1408static void kvm_copy_memslots(struct kvm_memslots *to,
1409			      struct kvm_memslots *from)
1410{
1411	memcpy(to, from, kvm_memslots_size(from->used_slots));
1412}
1413
1414/*
1415 * Note, at a minimum, the current number of used slots must be allocated, even
1416 * when deleting a memslot, as we need a complete duplicate of the memslots for
1417 * use when invalidating a memslot prior to deleting/moving the memslot.
1418 */
1419static struct kvm_memslots *kvm_dup_memslots(struct kvm_memslots *old,
1420					     enum kvm_mr_change change)
1421{
1422	struct kvm_memslots *slots;
1423	size_t new_size;
1424
1425	if (change == KVM_MR_CREATE)
1426		new_size = kvm_memslots_size(old->used_slots + 1);
1427	else
1428		new_size = kvm_memslots_size(old->used_slots);
1429
1430	slots = kvzalloc(new_size, GFP_KERNEL_ACCOUNT);
1431	if (likely(slots))
1432		kvm_copy_memslots(slots, old);
1433
1434	return slots;
1435}
1436
1437static int kvm_set_memslot(struct kvm *kvm,
1438			   const struct kvm_userspace_memory_region *mem,
1439			   struct kvm_memory_slot *old,
1440			   struct kvm_memory_slot *new, int as_id,
1441			   enum kvm_mr_change change)
1442{
1443	struct kvm_memory_slot *slot;
1444	struct kvm_memslots *slots;
1445	int r;
1446
1447	/*
1448	 * Released in install_new_memslots.
1449	 *
1450	 * Must be held from before the current memslots are copied until
1451	 * after the new memslots are installed with rcu_assign_pointer,
1452	 * then released before the synchronize srcu in install_new_memslots.
1453	 *
1454	 * When modifying memslots outside of the slots_lock, must be held
1455	 * before reading the pointer to the current memslots until after all
1456	 * changes to those memslots are complete.
1457	 *
1458	 * These rules ensure that installing new memslots does not lose
1459	 * changes made to the previous memslots.
1460	 */
1461	mutex_lock(&kvm->slots_arch_lock);
1462
1463	slots = kvm_dup_memslots(__kvm_memslots(kvm, as_id), change);
1464	if (!slots) {
1465		mutex_unlock(&kvm->slots_arch_lock);
1466		return -ENOMEM;
1467	}
1468
1469	if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
1470		/*
1471		 * Note, the INVALID flag needs to be in the appropriate entry
1472		 * in the freshly allocated memslots, not in @old or @new.
1473		 */
1474		slot = id_to_memslot(slots, old->id);
1475		slot->flags |= KVM_MEMSLOT_INVALID;
1476
1477		/*
1478		 * We can re-use the memory from the old memslots.
1479		 * It will be overwritten with a copy of the new memslots
1480		 * after reacquiring the slots_arch_lock below.
1481		 */
1482		slots = install_new_memslots(kvm, as_id, slots);
1483
1484		/* From this point no new shadow pages pointing to a deleted,
1485		 * or moved, memslot will be created.
1486		 *
1487		 * validation of sp->gfn happens in:
1488		 *	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
1489		 *	- kvm_is_visible_gfn (mmu_check_root)
1490		 */
1491		kvm_arch_flush_shadow_memslot(kvm, slot);
1492
1493		/* Released in install_new_memslots. */
1494		mutex_lock(&kvm->slots_arch_lock);
1495
1496		/*
1497		 * The arch-specific fields of the memslots could have changed
1498		 * between releasing the slots_arch_lock in
1499		 * install_new_memslots and here, so get a fresh copy of the
1500		 * slots.
1501		 */
1502		kvm_copy_memslots(slots, __kvm_memslots(kvm, as_id));
1503	}
1504
1505	r = kvm_arch_prepare_memory_region(kvm, new, mem, change);
1506	if (r)
1507		goto out_slots;
1508
1509	update_memslots(slots, new, change);
1510	slots = install_new_memslots(kvm, as_id, slots);
1511
1512	kvm_arch_commit_memory_region(kvm, mem, old, new, change);
1513
1514	kvfree(slots);
1515	return 0;
1516
1517out_slots:
1518	if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
1519		slot = id_to_memslot(slots, old->id);
1520		slot->flags &= ~KVM_MEMSLOT_INVALID;
1521		slots = install_new_memslots(kvm, as_id, slots);
1522	} else {
1523		mutex_unlock(&kvm->slots_arch_lock);
1524	}
1525	kvfree(slots);
1526	return r;
1527}
1528
1529static int kvm_delete_memslot(struct kvm *kvm,
1530			      const struct kvm_userspace_memory_region *mem,
1531			      struct kvm_memory_slot *old, int as_id)
1532{
1533	struct kvm_memory_slot new;
1534	int r;
1535
1536	if (!old->npages)
1537		return -EINVAL;
1538
1539	memset(&new, 0, sizeof(new));
1540	new.id = old->id;
1541	/*
1542	 * This is only for debugging purpose; it should never be referenced
1543	 * for a removed memslot.
1544	 */
1545	new.as_id = as_id;
1546
1547	r = kvm_set_memslot(kvm, mem, old, &new, as_id, KVM_MR_DELETE);
1548	if (r)
1549		return r;
1550
1551	kvm_free_memslot(kvm, old);
1552	return 0;
1553}
1554
1555/*
1556 * Allocate some memory and give it an address in the guest physical address
1557 * space.
1558 *
1559 * Discontiguous memory is allowed, mostly for framebuffers.
1560 *
1561 * Must be called holding kvm->slots_lock for write.
1562 */
1563int __kvm_set_memory_region(struct kvm *kvm,
1564			    const struct kvm_userspace_memory_region *mem)
1565{
 
 
 
 
1566	struct kvm_memory_slot old, new;
1567	struct kvm_memory_slot *tmp;
 
1568	enum kvm_mr_change change;
1569	int as_id, id;
1570	int r;
1571
1572	r = check_memory_region_flags(mem);
1573	if (r)
1574		return r;
1575
 
1576	as_id = mem->slot >> 16;
1577	id = (u16)mem->slot;
1578
1579	/* General sanity checks */
1580	if (mem->memory_size & (PAGE_SIZE - 1))
1581		return -EINVAL;
1582	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
1583		return -EINVAL;
1584	/* We can read the guest memory with __xxx_user() later on. */
1585	if ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
1586	    (mem->userspace_addr != untagged_addr(mem->userspace_addr)) ||
1587	     !access_ok((void __user *)(unsigned long)mem->userspace_addr,
1588			mem->memory_size))
1589		return -EINVAL;
 
1590	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
1591		return -EINVAL;
1592	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
1593		return -EINVAL;
 
 
 
 
1594
1595	/*
1596	 * Make a full copy of the old memslot, the pointer will become stale
1597	 * when the memslots are re-sorted by update_memslots(), and the old
1598	 * memslot needs to be referenced after calling update_memslots(), e.g.
1599	 * to free its resources and for arch specific behavior.
1600	 */
1601	tmp = id_to_memslot(__kvm_memslots(kvm, as_id), id);
1602	if (tmp) {
1603		old = *tmp;
1604		tmp = NULL;
1605	} else {
1606		memset(&old, 0, sizeof(old));
1607		old.id = id;
1608	}
1609
1610	if (!mem->memory_size)
1611		return kvm_delete_memslot(kvm, mem, &old, as_id);
1612
1613	new.as_id = as_id;
1614	new.id = id;
1615	new.base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
1616	new.npages = mem->memory_size >> PAGE_SHIFT;
1617	new.flags = mem->flags;
1618	new.userspace_addr = mem->userspace_addr;
1619
1620	if (new.npages > KVM_MEM_MAX_NR_PAGES)
1621		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1622
1623	if (!old.npages) {
1624		change = KVM_MR_CREATE;
1625		new.dirty_bitmap = NULL;
1626		memset(&new.arch, 0, sizeof(new.arch));
1627	} else { /* Modify an existing slot. */
1628		if ((new.userspace_addr != old.userspace_addr) ||
1629		    (new.npages != old.npages) ||
1630		    ((new.flags ^ old.flags) & KVM_MEM_READONLY))
1631			return -EINVAL;
1632
1633		if (new.base_gfn != old.base_gfn)
1634			change = KVM_MR_MOVE;
1635		else if (new.flags != old.flags)
1636			change = KVM_MR_FLAGS_ONLY;
1637		else /* Nothing to change. */
1638			return 0;
1639
1640		/* Copy dirty_bitmap and arch from the current memslot. */
1641		new.dirty_bitmap = old.dirty_bitmap;
1642		memcpy(&new.arch, &old.arch, sizeof(new.arch));
1643	}
1644
1645	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
1646		/* Check for overlaps */
1647		kvm_for_each_memslot(tmp, __kvm_memslots(kvm, as_id)) {
1648			if (tmp->id == id)
 
 
1649				continue;
1650			if (!((new.base_gfn + new.npages <= tmp->base_gfn) ||
1651			      (new.base_gfn >= tmp->base_gfn + tmp->npages)))
1652				return -EEXIST;
1653		}
1654	}
1655
1656	/* Allocate/free page dirty bitmap as needed */
1657	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
1658		new.dirty_bitmap = NULL;
1659	else if (!new.dirty_bitmap && !kvm->dirty_ring_size) {
1660		r = kvm_alloc_dirty_bitmap(&new);
1661		if (r)
1662			return r;
1663
1664		if (kvm_dirty_log_manual_protect_and_init_set(kvm))
1665			bitmap_set(new.dirty_bitmap, 0, new.npages);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1666	}
1667
1668	r = kvm_set_memslot(kvm, mem, &old, &new, as_id, change);
1669	if (r)
1670		goto out_bitmap;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1671
1672	if (old.dirty_bitmap && !new.dirty_bitmap)
1673		kvm_destroy_dirty_bitmap(&old);
1674	return 0;
1675
1676out_bitmap:
1677	if (new.dirty_bitmap && !old.dirty_bitmap)
1678		kvm_destroy_dirty_bitmap(&new);
 
 
1679	return r;
1680}
1681EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
1682
1683int kvm_set_memory_region(struct kvm *kvm,
1684			  const struct kvm_userspace_memory_region *mem)
1685{
1686	int r;
1687
1688	mutex_lock(&kvm->slots_lock);
1689	r = __kvm_set_memory_region(kvm, mem);
1690	mutex_unlock(&kvm->slots_lock);
1691	return r;
1692}
1693EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1694
1695static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1696					  struct kvm_userspace_memory_region *mem)
1697{
1698	if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1699		return -EINVAL;
1700
1701	return kvm_set_memory_region(kvm, mem);
1702}
1703
1704#ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
1705/**
1706 * kvm_get_dirty_log - get a snapshot of dirty pages
1707 * @kvm:	pointer to kvm instance
1708 * @log:	slot id and address to which we copy the log
1709 * @is_dirty:	set to '1' if any dirty pages were found
1710 * @memslot:	set to the associated memslot, always valid on success
1711 */
1712int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log,
1713		      int *is_dirty, struct kvm_memory_slot **memslot)
1714{
1715	struct kvm_memslots *slots;
1716	int i, as_id, id;
 
1717	unsigned long n;
1718	unsigned long any = 0;
1719
1720	/* Dirty ring tracking is exclusive to dirty log tracking */
1721	if (kvm->dirty_ring_size)
1722		return -ENXIO;
1723
1724	*memslot = NULL;
1725	*is_dirty = 0;
1726
1727	as_id = log->slot >> 16;
1728	id = (u16)log->slot;
1729	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1730		return -EINVAL;
1731
1732	slots = __kvm_memslots(kvm, as_id);
1733	*memslot = id_to_memslot(slots, id);
1734	if (!(*memslot) || !(*memslot)->dirty_bitmap)
1735		return -ENOENT;
 
1736
1737	kvm_arch_sync_dirty_log(kvm, *memslot);
1738
1739	n = kvm_dirty_bitmap_bytes(*memslot);
1740
1741	for (i = 0; !any && i < n/sizeof(long); ++i)
1742		any = (*memslot)->dirty_bitmap[i];
1743
1744	if (copy_to_user(log->dirty_bitmap, (*memslot)->dirty_bitmap, n))
1745		return -EFAULT;
 
1746
1747	if (any)
1748		*is_dirty = 1;
1749	return 0;
 
 
 
1750}
1751EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
1752
1753#else /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
1754/**
1755 * kvm_get_dirty_log_protect - get a snapshot of dirty pages
1756 *	and reenable dirty page tracking for the corresponding pages.
1757 * @kvm:	pointer to kvm instance
1758 * @log:	slot id and address to which we copy the log
 
1759 *
1760 * We need to keep it in mind that VCPU threads can write to the bitmap
1761 * concurrently. So, to avoid losing track of dirty pages we keep the
1762 * following order:
1763 *
1764 *    1. Take a snapshot of the bit and clear it if needed.
1765 *    2. Write protect the corresponding page.
1766 *    3. Copy the snapshot to the userspace.
1767 *    4. Upon return caller flushes TLB's if needed.
1768 *
1769 * Between 2 and 4, the guest may write to the page using the remaining TLB
1770 * entry.  This is not a problem because the page is reported dirty using
1771 * the snapshot taken before and step 4 ensures that writes done after
1772 * exiting to userspace will be logged for the next call.
1773 *
1774 */
1775static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
 
1776{
1777	struct kvm_memslots *slots;
1778	struct kvm_memory_slot *memslot;
1779	int i, as_id, id;
1780	unsigned long n;
1781	unsigned long *dirty_bitmap;
1782	unsigned long *dirty_bitmap_buffer;
1783	bool flush;
1784
1785	/* Dirty ring tracking is exclusive to dirty log tracking */
1786	if (kvm->dirty_ring_size)
1787		return -ENXIO;
1788
 
1789	as_id = log->slot >> 16;
1790	id = (u16)log->slot;
1791	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1792		return -EINVAL;
1793
1794	slots = __kvm_memslots(kvm, as_id);
1795	memslot = id_to_memslot(slots, id);
1796	if (!memslot || !memslot->dirty_bitmap)
1797		return -ENOENT;
1798
1799	dirty_bitmap = memslot->dirty_bitmap;
 
 
 
1800
1801	kvm_arch_sync_dirty_log(kvm, memslot);
1802
1803	n = kvm_dirty_bitmap_bytes(memslot);
1804	flush = false;
1805	if (kvm->manual_dirty_log_protect) {
1806		/*
1807		 * Unlike kvm_get_dirty_log, we always return false in *flush,
1808		 * because no flush is needed until KVM_CLEAR_DIRTY_LOG.  There
1809		 * is some code duplication between this function and
1810		 * kvm_get_dirty_log, but hopefully all architecture
1811		 * transition to kvm_get_dirty_log_protect and kvm_get_dirty_log
1812		 * can be eliminated.
1813		 */
1814		dirty_bitmap_buffer = dirty_bitmap;
1815	} else {
1816		dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
1817		memset(dirty_bitmap_buffer, 0, n);
1818
1819		KVM_MMU_LOCK(kvm);
1820		for (i = 0; i < n / sizeof(long); i++) {
1821			unsigned long mask;
1822			gfn_t offset;
1823
1824			if (!dirty_bitmap[i])
1825				continue;
1826
1827			flush = true;
1828			mask = xchg(&dirty_bitmap[i], 0);
1829			dirty_bitmap_buffer[i] = mask;
1830
 
1831			offset = i * BITS_PER_LONG;
1832			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1833								offset, mask);
1834		}
1835		KVM_MMU_UNLOCK(kvm);
1836	}
1837
1838	if (flush)
1839		kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
1840
 
1841	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
1842		return -EFAULT;
1843	return 0;
1844}
1845
1846
1847/**
1848 * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
1849 * @kvm: kvm instance
1850 * @log: slot id and address to which we copy the log
1851 *
1852 * Steps 1-4 below provide general overview of dirty page logging. See
1853 * kvm_get_dirty_log_protect() function description for additional details.
1854 *
1855 * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
1856 * always flush the TLB (step 4) even if previous step failed  and the dirty
1857 * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
1858 * does not preclude user space subsequent dirty log read. Flushing TLB ensures
1859 * writes will be marked dirty for next log read.
1860 *
1861 *   1. Take a snapshot of the bit and clear it if needed.
1862 *   2. Write protect the corresponding page.
1863 *   3. Copy the snapshot to the userspace.
1864 *   4. Flush TLB's if needed.
1865 */
1866static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
1867				      struct kvm_dirty_log *log)
1868{
1869	int r;
1870
1871	mutex_lock(&kvm->slots_lock);
1872
1873	r = kvm_get_dirty_log_protect(kvm, log);
1874
1875	mutex_unlock(&kvm->slots_lock);
1876	return r;
1877}
 
 
1878
1879/**
1880 * kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
1881 *	and reenable dirty page tracking for the corresponding pages.
1882 * @kvm:	pointer to kvm instance
1883 * @log:	slot id and address from which to fetch the bitmap of dirty pages
1884 */
1885static int kvm_clear_dirty_log_protect(struct kvm *kvm,
1886				       struct kvm_clear_dirty_log *log)
1887{
1888	struct kvm_memslots *slots;
1889	struct kvm_memory_slot *memslot;
1890	int as_id, id;
1891	gfn_t offset;
1892	unsigned long i, n;
1893	unsigned long *dirty_bitmap;
1894	unsigned long *dirty_bitmap_buffer;
1895	bool flush;
1896
1897	/* Dirty ring tracking is exclusive to dirty log tracking */
1898	if (kvm->dirty_ring_size)
1899		return -ENXIO;
1900
1901	as_id = log->slot >> 16;
1902	id = (u16)log->slot;
1903	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1904		return -EINVAL;
1905
1906	if (log->first_page & 63)
1907		return -EINVAL;
1908
1909	slots = __kvm_memslots(kvm, as_id);
1910	memslot = id_to_memslot(slots, id);
1911	if (!memslot || !memslot->dirty_bitmap)
1912		return -ENOENT;
1913
1914	dirty_bitmap = memslot->dirty_bitmap;
1915
1916	n = ALIGN(log->num_pages, BITS_PER_LONG) / 8;
1917
1918	if (log->first_page > memslot->npages ||
1919	    log->num_pages > memslot->npages - log->first_page ||
1920	    (log->num_pages < memslot->npages - log->first_page && (log->num_pages & 63)))
1921	    return -EINVAL;
1922
1923	kvm_arch_sync_dirty_log(kvm, memslot);
1924
1925	flush = false;
1926	dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
1927	if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
1928		return -EFAULT;
1929
1930	KVM_MMU_LOCK(kvm);
1931	for (offset = log->first_page, i = offset / BITS_PER_LONG,
1932		 n = DIV_ROUND_UP(log->num_pages, BITS_PER_LONG); n--;
1933	     i++, offset += BITS_PER_LONG) {
1934		unsigned long mask = *dirty_bitmap_buffer++;
1935		atomic_long_t *p = (atomic_long_t *) &dirty_bitmap[i];
1936		if (!mask)
1937			continue;
1938
1939		mask &= atomic_long_fetch_andnot(mask, p);
1940
1941		/*
1942		 * mask contains the bits that really have been cleared.  This
1943		 * never includes any bits beyond the length of the memslot (if
1944		 * the length is not aligned to 64 pages), therefore it is not
1945		 * a problem if userspace sets them in log->dirty_bitmap.
1946		*/
1947		if (mask) {
1948			flush = true;
1949			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1950								offset, mask);
1951		}
1952	}
1953	KVM_MMU_UNLOCK(kvm);
1954
1955	if (flush)
1956		kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
1957
1958	return 0;
1959}
1960
1961static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm,
1962					struct kvm_clear_dirty_log *log)
1963{
1964	int r;
1965
1966	mutex_lock(&kvm->slots_lock);
1967
1968	r = kvm_clear_dirty_log_protect(kvm, log);
1969
1970	mutex_unlock(&kvm->slots_lock);
1971	return r;
1972}
1973#endif /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
1974
1975struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1976{
1977	return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1978}
1979EXPORT_SYMBOL_GPL(gfn_to_memslot);
1980
1981struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
1982{
1983	return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
1984}
1985EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot);
1986
1987bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1988{
1989	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1990
1991	return kvm_is_visible_memslot(memslot);
 
 
 
 
1992}
1993EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1994
1995bool kvm_vcpu_is_visible_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1996{
1997	struct kvm_memory_slot *memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1998
1999	return kvm_is_visible_memslot(memslot);
2000}
2001EXPORT_SYMBOL_GPL(kvm_vcpu_is_visible_gfn);
2002
2003unsigned long kvm_host_page_size(struct kvm_vcpu *vcpu, gfn_t gfn)
2004{
2005	struct vm_area_struct *vma;
2006	unsigned long addr, size;
2007
2008	size = PAGE_SIZE;
2009
2010	addr = kvm_vcpu_gfn_to_hva_prot(vcpu, gfn, NULL);
2011	if (kvm_is_error_hva(addr))
2012		return PAGE_SIZE;
2013
2014	mmap_read_lock(current->mm);
2015	vma = find_vma(current->mm, addr);
2016	if (!vma)
2017		goto out;
2018
2019	size = vma_kernel_pagesize(vma);
2020
2021out:
2022	mmap_read_unlock(current->mm);
2023
2024	return size;
2025}
2026
2027static bool memslot_is_readonly(struct kvm_memory_slot *slot)
2028{
2029	return slot->flags & KVM_MEM_READONLY;
2030}
2031
2032static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
2033				       gfn_t *nr_pages, bool write)
2034{
2035	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
2036		return KVM_HVA_ERR_BAD;
2037
2038	if (memslot_is_readonly(slot) && write)
2039		return KVM_HVA_ERR_RO_BAD;
2040
2041	if (nr_pages)
2042		*nr_pages = slot->npages - (gfn - slot->base_gfn);
2043
2044	return __gfn_to_hva_memslot(slot, gfn);
2045}
2046
2047static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
2048				     gfn_t *nr_pages)
2049{
2050	return __gfn_to_hva_many(slot, gfn, nr_pages, true);
2051}
2052
2053unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
2054					gfn_t gfn)
2055{
2056	return gfn_to_hva_many(slot, gfn, NULL);
2057}
2058EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
2059
2060unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
2061{
2062	return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
2063}
2064EXPORT_SYMBOL_GPL(gfn_to_hva);
2065
2066unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
2067{
2068	return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
2069}
2070EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);
2071
2072/*
2073 * Return the hva of a @gfn and the R/W attribute if possible.
2074 *
2075 * @slot: the kvm_memory_slot which contains @gfn
2076 * @gfn: the gfn to be translated
2077 * @writable: used to return the read/write attribute of the @slot if the hva
2078 * is valid and @writable is not NULL
2079 */
2080unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
2081				      gfn_t gfn, bool *writable)
2082{
2083	unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
2084
2085	if (!kvm_is_error_hva(hva) && writable)
2086		*writable = !memslot_is_readonly(slot);
2087
2088	return hva;
2089}
2090
2091unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
2092{
2093	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
2094
2095	return gfn_to_hva_memslot_prot(slot, gfn, writable);
2096}
2097
2098unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
2099{
2100	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2101
2102	return gfn_to_hva_memslot_prot(slot, gfn, writable);
2103}
2104
 
 
 
 
 
 
 
 
 
 
 
 
2105static inline int check_user_page_hwpoison(unsigned long addr)
2106{
2107	int rc, flags = FOLL_HWPOISON | FOLL_WRITE;
2108
2109	rc = get_user_pages(addr, 1, flags, NULL, NULL);
 
2110	return rc == -EHWPOISON;
2111}
2112
2113/*
2114 * The fast path to get the writable pfn which will be stored in @pfn,
2115 * true indicates success, otherwise false is returned.  It's also the
2116 * only part that runs if we can in atomic context.
2117 */
2118static bool hva_to_pfn_fast(unsigned long addr, bool write_fault,
2119			    bool *writable, kvm_pfn_t *pfn)
2120{
2121	struct page *page[1];
 
 
 
 
2122
2123	/*
2124	 * Fast pin a writable pfn only if it is a write fault request
2125	 * or the caller allows to map a writable pfn for a read fault
2126	 * request.
2127	 */
2128	if (!(write_fault || writable))
2129		return false;
2130
2131	if (get_user_page_fast_only(addr, FOLL_WRITE, page)) {
 
2132		*pfn = page_to_pfn(page[0]);
2133
2134		if (writable)
2135			*writable = true;
2136		return true;
2137	}
2138
2139	return false;
2140}
2141
2142/*
2143 * The slow path to get the pfn of the specified host virtual address,
2144 * 1 indicates success, -errno is returned if error is detected.
2145 */
2146static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
2147			   bool *writable, kvm_pfn_t *pfn)
2148{
2149	unsigned int flags = FOLL_HWPOISON;
2150	struct page *page;
2151	int npages = 0;
2152
2153	might_sleep();
2154
2155	if (writable)
2156		*writable = write_fault;
2157
2158	if (write_fault)
2159		flags |= FOLL_WRITE;
2160	if (async)
2161		flags |= FOLL_NOWAIT;
2162
2163	npages = get_user_pages_unlocked(addr, 1, &page, flags);
 
 
2164	if (npages != 1)
2165		return npages;
2166
2167	/* map read fault as writable if possible */
2168	if (unlikely(!write_fault) && writable) {
2169		struct page *wpage;
2170
2171		if (get_user_page_fast_only(addr, FOLL_WRITE, &wpage)) {
 
2172			*writable = true;
2173			put_page(page);
2174			page = wpage;
2175		}
 
 
2176	}
2177	*pfn = page_to_pfn(page);
2178	return npages;
2179}
2180
2181static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
2182{
2183	if (unlikely(!(vma->vm_flags & VM_READ)))
2184		return false;
2185
2186	if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
2187		return false;
2188
2189	return true;
2190}
2191
2192static int kvm_try_get_pfn(kvm_pfn_t pfn)
2193{
2194	if (kvm_is_reserved_pfn(pfn))
2195		return 1;
2196	return get_page_unless_zero(pfn_to_page(pfn));
2197}
2198
2199static int hva_to_pfn_remapped(struct vm_area_struct *vma,
2200			       unsigned long addr, bool *async,
2201			       bool write_fault, bool *writable,
2202			       kvm_pfn_t *p_pfn)
2203{
2204	kvm_pfn_t pfn;
2205	pte_t *ptep;
2206	spinlock_t *ptl;
2207	int r;
2208
2209	r = follow_pte(vma->vm_mm, addr, &ptep, &ptl);
2210	if (r) {
2211		/*
2212		 * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
2213		 * not call the fault handler, so do it here.
2214		 */
2215		bool unlocked = false;
2216		r = fixup_user_fault(current->mm, addr,
2217				     (write_fault ? FAULT_FLAG_WRITE : 0),
2218				     &unlocked);
2219		if (unlocked)
2220			return -EAGAIN;
2221		if (r)
2222			return r;
2223
2224		r = follow_pte(vma->vm_mm, addr, &ptep, &ptl);
2225		if (r)
2226			return r;
2227	}
2228
2229	if (write_fault && !pte_write(*ptep)) {
2230		pfn = KVM_PFN_ERR_RO_FAULT;
2231		goto out;
2232	}
2233
2234	if (writable)
2235		*writable = pte_write(*ptep);
2236	pfn = pte_pfn(*ptep);
2237
2238	/*
2239	 * Get a reference here because callers of *hva_to_pfn* and
2240	 * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
2241	 * returned pfn.  This is only needed if the VMA has VM_MIXEDMAP
2242	 * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will
2243	 * simply do nothing for reserved pfns.
2244	 *
2245	 * Whoever called remap_pfn_range is also going to call e.g.
2246	 * unmap_mapping_range before the underlying pages are freed,
2247	 * causing a call to our MMU notifier.
2248	 *
2249	 * Certain IO or PFNMAP mappings can be backed with valid
2250	 * struct pages, but be allocated without refcounting e.g.,
2251	 * tail pages of non-compound higher order allocations, which
2252	 * would then underflow the refcount when the caller does the
2253	 * required put_page. Don't allow those pages here.
2254	 */ 
2255	if (!kvm_try_get_pfn(pfn))
2256		r = -EFAULT;
2257
2258out:
2259	pte_unmap_unlock(ptep, ptl);
2260	*p_pfn = pfn;
2261
2262	return r;
2263}
2264
2265/*
2266 * Pin guest page in memory and return its pfn.
2267 * @addr: host virtual address which maps memory to the guest
2268 * @atomic: whether this function can sleep
2269 * @async: whether this function need to wait IO complete if the
2270 *         host page is not in the memory
2271 * @write_fault: whether we should get a writable host page
2272 * @writable: whether it allows to map a writable host page for !@write_fault
2273 *
2274 * The function will map a writable host page for these two cases:
2275 * 1): @write_fault = true
2276 * 2): @write_fault = false && @writable, @writable will tell the caller
2277 *     whether the mapping is writable.
2278 */
2279static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
2280			bool write_fault, bool *writable)
2281{
2282	struct vm_area_struct *vma;
2283	kvm_pfn_t pfn = 0;
2284	int npages, r;
2285
2286	/* we can do it either atomically or asynchronously, not both */
2287	BUG_ON(atomic && async);
2288
2289	if (hva_to_pfn_fast(addr, write_fault, writable, &pfn))
2290		return pfn;
2291
2292	if (atomic)
2293		return KVM_PFN_ERR_FAULT;
2294
2295	npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
2296	if (npages == 1)
2297		return pfn;
2298
2299	mmap_read_lock(current->mm);
2300	if (npages == -EHWPOISON ||
2301	      (!async && check_user_page_hwpoison(addr))) {
2302		pfn = KVM_PFN_ERR_HWPOISON;
2303		goto exit;
2304	}
2305
2306retry:
2307	vma = vma_lookup(current->mm, addr);
2308
2309	if (vma == NULL)
2310		pfn = KVM_PFN_ERR_FAULT;
2311	else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) {
2312		r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn);
2313		if (r == -EAGAIN)
2314			goto retry;
2315		if (r < 0)
2316			pfn = KVM_PFN_ERR_FAULT;
2317	} else {
2318		if (async && vma_is_valid(vma, write_fault))
2319			*async = true;
2320		pfn = KVM_PFN_ERR_FAULT;
2321	}
2322exit:
2323	mmap_read_unlock(current->mm);
2324	return pfn;
2325}
2326
2327kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn,
2328			       bool atomic, bool *async, bool write_fault,
2329			       bool *writable, hva_t *hva)
2330{
2331	unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
2332
2333	if (hva)
2334		*hva = addr;
2335
2336	if (addr == KVM_HVA_ERR_RO_BAD) {
2337		if (writable)
2338			*writable = false;
2339		return KVM_PFN_ERR_RO_FAULT;
2340	}
2341
2342	if (kvm_is_error_hva(addr)) {
2343		if (writable)
2344			*writable = false;
2345		return KVM_PFN_NOSLOT;
2346	}
2347
2348	/* Do not map writable pfn in the readonly memslot. */
2349	if (writable && memslot_is_readonly(slot)) {
2350		*writable = false;
2351		writable = NULL;
2352	}
2353
2354	return hva_to_pfn(addr, atomic, async, write_fault,
2355			  writable);
2356}
2357EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
2358
2359kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
2360		      bool *writable)
2361{
2362	return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
2363				    write_fault, writable, NULL);
2364}
2365EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
2366
2367kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
2368{
2369	return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL, NULL);
2370}
2371EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
2372
2373kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
2374{
2375	return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL, NULL);
2376}
2377EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
2378
 
 
 
 
 
 
2379kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
2380{
2381	return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
2382}
2383EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
2384
2385kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
2386{
2387	return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
2388}
2389EXPORT_SYMBOL_GPL(gfn_to_pfn);
2390
2391kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
2392{
2393	return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
2394}
2395EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
2396
2397int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
2398			    struct page **pages, int nr_pages)
2399{
2400	unsigned long addr;
2401	gfn_t entry = 0;
2402
2403	addr = gfn_to_hva_many(slot, gfn, &entry);
2404	if (kvm_is_error_hva(addr))
2405		return -1;
2406
2407	if (entry < nr_pages)
2408		return 0;
2409
2410	return get_user_pages_fast_only(addr, nr_pages, FOLL_WRITE, pages);
2411}
2412EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
2413
2414static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
2415{
2416	if (is_error_noslot_pfn(pfn))
2417		return KVM_ERR_PTR_BAD_PAGE;
2418
2419	if (kvm_is_reserved_pfn(pfn)) {
2420		WARN_ON(1);
2421		return KVM_ERR_PTR_BAD_PAGE;
2422	}
2423
2424	return pfn_to_page(pfn);
2425}
2426
2427struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
2428{
2429	kvm_pfn_t pfn;
2430
2431	pfn = gfn_to_pfn(kvm, gfn);
2432
2433	return kvm_pfn_to_page(pfn);
2434}
2435EXPORT_SYMBOL_GPL(gfn_to_page);
2436
2437void kvm_release_pfn(kvm_pfn_t pfn, bool dirty, struct gfn_to_pfn_cache *cache)
2438{
2439	if (pfn == 0)
2440		return;
2441
2442	if (cache)
2443		cache->pfn = cache->gfn = 0;
2444
2445	if (dirty)
2446		kvm_release_pfn_dirty(pfn);
2447	else
2448		kvm_release_pfn_clean(pfn);
2449}
2450
2451static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot *slot, gfn_t gfn,
2452				 struct gfn_to_pfn_cache *cache, u64 gen)
2453{
2454	kvm_release_pfn(cache->pfn, cache->dirty, cache);
2455
2456	cache->pfn = gfn_to_pfn_memslot(slot, gfn);
2457	cache->gfn = gfn;
2458	cache->dirty = false;
2459	cache->generation = gen;
2460}
2461
2462static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn,
2463			 struct kvm_host_map *map,
2464			 struct gfn_to_pfn_cache *cache,
2465			 bool atomic)
2466{
2467	kvm_pfn_t pfn;
2468	void *hva = NULL;
2469	struct page *page = KVM_UNMAPPED_PAGE;
2470	struct kvm_memory_slot *slot = __gfn_to_memslot(slots, gfn);
2471	u64 gen = slots->generation;
2472
2473	if (!map)
2474		return -EINVAL;
2475
2476	if (cache) {
2477		if (!cache->pfn || cache->gfn != gfn ||
2478			cache->generation != gen) {
2479			if (atomic)
2480				return -EAGAIN;
2481			kvm_cache_gfn_to_pfn(slot, gfn, cache, gen);
2482		}
2483		pfn = cache->pfn;
2484	} else {
2485		if (atomic)
2486			return -EAGAIN;
2487		pfn = gfn_to_pfn_memslot(slot, gfn);
2488	}
2489	if (is_error_noslot_pfn(pfn))
2490		return -EINVAL;
2491
2492	if (pfn_valid(pfn)) {
2493		page = pfn_to_page(pfn);
2494		if (atomic)
2495			hva = kmap_atomic(page);
2496		else
2497			hva = kmap(page);
2498#ifdef CONFIG_HAS_IOMEM
2499	} else if (!atomic) {
2500		hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
2501	} else {
2502		return -EINVAL;
2503#endif
2504	}
2505
2506	if (!hva)
2507		return -EFAULT;
2508
2509	map->page = page;
2510	map->hva = hva;
2511	map->pfn = pfn;
2512	map->gfn = gfn;
2513
2514	return 0;
2515}
2516
2517int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map,
2518		struct gfn_to_pfn_cache *cache, bool atomic)
2519{
2520	return __kvm_map_gfn(kvm_memslots(vcpu->kvm), gfn, map,
2521			cache, atomic);
2522}
2523EXPORT_SYMBOL_GPL(kvm_map_gfn);
2524
2525int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
2526{
2527	return __kvm_map_gfn(kvm_vcpu_memslots(vcpu), gfn, map,
2528		NULL, false);
2529}
2530EXPORT_SYMBOL_GPL(kvm_vcpu_map);
2531
2532static void __kvm_unmap_gfn(struct kvm *kvm,
2533			struct kvm_memory_slot *memslot,
2534			struct kvm_host_map *map,
2535			struct gfn_to_pfn_cache *cache,
2536			bool dirty, bool atomic)
2537{
2538	if (!map)
2539		return;
2540
2541	if (!map->hva)
2542		return;
2543
2544	if (map->page != KVM_UNMAPPED_PAGE) {
2545		if (atomic)
2546			kunmap_atomic(map->hva);
2547		else
2548			kunmap(map->page);
2549	}
2550#ifdef CONFIG_HAS_IOMEM
2551	else if (!atomic)
2552		memunmap(map->hva);
2553	else
2554		WARN_ONCE(1, "Unexpected unmapping in atomic context");
2555#endif
2556
2557	if (dirty)
2558		mark_page_dirty_in_slot(kvm, memslot, map->gfn);
2559
2560	if (cache)
2561		cache->dirty |= dirty;
2562	else
2563		kvm_release_pfn(map->pfn, dirty, NULL);
2564
2565	map->hva = NULL;
2566	map->page = NULL;
2567}
2568
2569int kvm_unmap_gfn(struct kvm_vcpu *vcpu, struct kvm_host_map *map, 
2570		  struct gfn_to_pfn_cache *cache, bool dirty, bool atomic)
2571{
2572	__kvm_unmap_gfn(vcpu->kvm, gfn_to_memslot(vcpu->kvm, map->gfn), map,
2573			cache, dirty, atomic);
2574	return 0;
2575}
2576EXPORT_SYMBOL_GPL(kvm_unmap_gfn);
2577
2578void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
2579{
2580	__kvm_unmap_gfn(vcpu->kvm, kvm_vcpu_gfn_to_memslot(vcpu, map->gfn),
2581			map, NULL, dirty, false);
2582}
2583EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);
2584
2585struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
2586{
2587	kvm_pfn_t pfn;
2588
2589	pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);
2590
2591	return kvm_pfn_to_page(pfn);
2592}
2593EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);
2594
2595void kvm_release_page_clean(struct page *page)
2596{
2597	WARN_ON(is_error_page(page));
2598
2599	kvm_release_pfn_clean(page_to_pfn(page));
2600}
2601EXPORT_SYMBOL_GPL(kvm_release_page_clean);
2602
2603void kvm_release_pfn_clean(kvm_pfn_t pfn)
2604{
2605	if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
2606		put_page(pfn_to_page(pfn));
2607}
2608EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
2609
2610void kvm_release_page_dirty(struct page *page)
2611{
2612	WARN_ON(is_error_page(page));
2613
2614	kvm_release_pfn_dirty(page_to_pfn(page));
2615}
2616EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
2617
2618void kvm_release_pfn_dirty(kvm_pfn_t pfn)
2619{
2620	kvm_set_pfn_dirty(pfn);
2621	kvm_release_pfn_clean(pfn);
2622}
2623EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
2624
2625void kvm_set_pfn_dirty(kvm_pfn_t pfn)
2626{
2627	if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
2628		SetPageDirty(pfn_to_page(pfn));
 
 
 
 
2629}
2630EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
2631
2632void kvm_set_pfn_accessed(kvm_pfn_t pfn)
2633{
2634	if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
2635		mark_page_accessed(pfn_to_page(pfn));
2636}
2637EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
2638
2639void kvm_get_pfn(kvm_pfn_t pfn)
2640{
2641	if (!kvm_is_reserved_pfn(pfn))
2642		get_page(pfn_to_page(pfn));
2643}
2644EXPORT_SYMBOL_GPL(kvm_get_pfn);
2645
2646static int next_segment(unsigned long len, int offset)
2647{
2648	if (len > PAGE_SIZE - offset)
2649		return PAGE_SIZE - offset;
2650	else
2651		return len;
2652}
2653
2654static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
2655				 void *data, int offset, int len)
2656{
2657	int r;
2658	unsigned long addr;
2659
2660	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
2661	if (kvm_is_error_hva(addr))
2662		return -EFAULT;
2663	r = __copy_from_user(data, (void __user *)addr + offset, len);
2664	if (r)
2665		return -EFAULT;
2666	return 0;
2667}
2668
2669int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
2670			int len)
2671{
2672	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
2673
2674	return __kvm_read_guest_page(slot, gfn, data, offset, len);
2675}
2676EXPORT_SYMBOL_GPL(kvm_read_guest_page);
2677
2678int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
2679			     int offset, int len)
2680{
2681	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2682
2683	return __kvm_read_guest_page(slot, gfn, data, offset, len);
2684}
2685EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);
2686
2687int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
2688{
2689	gfn_t gfn = gpa >> PAGE_SHIFT;
2690	int seg;
2691	int offset = offset_in_page(gpa);
2692	int ret;
2693
2694	while ((seg = next_segment(len, offset)) != 0) {
2695		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
2696		if (ret < 0)
2697			return ret;
2698		offset = 0;
2699		len -= seg;
2700		data += seg;
2701		++gfn;
2702	}
2703	return 0;
2704}
2705EXPORT_SYMBOL_GPL(kvm_read_guest);
2706
2707int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
2708{
2709	gfn_t gfn = gpa >> PAGE_SHIFT;
2710	int seg;
2711	int offset = offset_in_page(gpa);
2712	int ret;
2713
2714	while ((seg = next_segment(len, offset)) != 0) {
2715		ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
2716		if (ret < 0)
2717			return ret;
2718		offset = 0;
2719		len -= seg;
2720		data += seg;
2721		++gfn;
2722	}
2723	return 0;
2724}
2725EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
2726
2727static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
2728			           void *data, int offset, unsigned long len)
2729{
2730	int r;
2731	unsigned long addr;
2732
2733	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
2734	if (kvm_is_error_hva(addr))
2735		return -EFAULT;
2736	pagefault_disable();
2737	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
2738	pagefault_enable();
2739	if (r)
2740		return -EFAULT;
2741	return 0;
2742}
2743
 
 
 
 
 
 
 
 
 
 
 
2744int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
2745			       void *data, unsigned long len)
2746{
2747	gfn_t gfn = gpa >> PAGE_SHIFT;
2748	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2749	int offset = offset_in_page(gpa);
2750
2751	return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
2752}
2753EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
2754
2755static int __kvm_write_guest_page(struct kvm *kvm,
2756				  struct kvm_memory_slot *memslot, gfn_t gfn,
2757			          const void *data, int offset, int len)
2758{
2759	int r;
2760	unsigned long addr;
2761
2762	addr = gfn_to_hva_memslot(memslot, gfn);
2763	if (kvm_is_error_hva(addr))
2764		return -EFAULT;
2765	r = __copy_to_user((void __user *)addr + offset, data, len);
2766	if (r)
2767		return -EFAULT;
2768	mark_page_dirty_in_slot(kvm, memslot, gfn);
2769	return 0;
2770}
2771
2772int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
2773			 const void *data, int offset, int len)
2774{
2775	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
2776
2777	return __kvm_write_guest_page(kvm, slot, gfn, data, offset, len);
2778}
2779EXPORT_SYMBOL_GPL(kvm_write_guest_page);
2780
2781int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
2782			      const void *data, int offset, int len)
2783{
2784	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2785
2786	return __kvm_write_guest_page(vcpu->kvm, slot, gfn, data, offset, len);
2787}
2788EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
2789
2790int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
2791		    unsigned long len)
2792{
2793	gfn_t gfn = gpa >> PAGE_SHIFT;
2794	int seg;
2795	int offset = offset_in_page(gpa);
2796	int ret;
2797
2798	while ((seg = next_segment(len, offset)) != 0) {
2799		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
2800		if (ret < 0)
2801			return ret;
2802		offset = 0;
2803		len -= seg;
2804		data += seg;
2805		++gfn;
2806	}
2807	return 0;
2808}
2809EXPORT_SYMBOL_GPL(kvm_write_guest);
2810
2811int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
2812		         unsigned long len)
2813{
2814	gfn_t gfn = gpa >> PAGE_SHIFT;
2815	int seg;
2816	int offset = offset_in_page(gpa);
2817	int ret;
2818
2819	while ((seg = next_segment(len, offset)) != 0) {
2820		ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
2821		if (ret < 0)
2822			return ret;
2823		offset = 0;
2824		len -= seg;
2825		data += seg;
2826		++gfn;
2827	}
2828	return 0;
2829}
2830EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
2831
2832static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
2833				       struct gfn_to_hva_cache *ghc,
2834				       gpa_t gpa, unsigned long len)
2835{
 
2836	int offset = offset_in_page(gpa);
2837	gfn_t start_gfn = gpa >> PAGE_SHIFT;
2838	gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
2839	gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
2840	gfn_t nr_pages_avail;
2841
2842	/* Update ghc->generation before performing any error checks. */
2843	ghc->generation = slots->generation;
2844
2845	if (start_gfn > end_gfn) {
2846		ghc->hva = KVM_HVA_ERR_BAD;
2847		return -EINVAL;
2848	}
2849
2850	/*
2851	 * If the requested region crosses two memslots, we still
2852	 * verify that the entire region is valid here.
2853	 */
2854	for ( ; start_gfn <= end_gfn; start_gfn += nr_pages_avail) {
2855		ghc->memslot = __gfn_to_memslot(slots, start_gfn);
2856		ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
2857					   &nr_pages_avail);
2858		if (kvm_is_error_hva(ghc->hva))
2859			return -EFAULT;
2860	}
2861
2862	/* Use the slow path for cross page reads and writes. */
2863	if (nr_pages_needed == 1)
2864		ghc->hva += offset;
2865	else
 
 
 
 
 
 
 
 
 
 
 
 
 
2866		ghc->memslot = NULL;
2867
2868	ghc->gpa = gpa;
2869	ghc->len = len;
2870	return 0;
2871}
2872
2873int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2874			      gpa_t gpa, unsigned long len)
2875{
2876	struct kvm_memslots *slots = kvm_memslots(kvm);
2877	return __kvm_gfn_to_hva_cache_init(slots, ghc, gpa, len);
2878}
2879EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
2880
2881int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2882				  void *data, unsigned int offset,
2883				  unsigned long len)
2884{
2885	struct kvm_memslots *slots = kvm_memslots(kvm);
2886	int r;
2887	gpa_t gpa = ghc->gpa + offset;
2888
2889	BUG_ON(len + offset > ghc->len);
2890
2891	if (slots->generation != ghc->generation) {
2892		if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
2893			return -EFAULT;
2894	}
 
2895
2896	if (kvm_is_error_hva(ghc->hva))
2897		return -EFAULT;
2898
2899	if (unlikely(!ghc->memslot))
2900		return kvm_write_guest(kvm, gpa, data, len);
2901
2902	r = __copy_to_user((void __user *)ghc->hva + offset, data, len);
2903	if (r)
2904		return -EFAULT;
2905	mark_page_dirty_in_slot(kvm, ghc->memslot, gpa >> PAGE_SHIFT);
2906
2907	return 0;
2908}
2909EXPORT_SYMBOL_GPL(kvm_write_guest_offset_cached);
2910
2911int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2912			   void *data, unsigned long len)
2913{
2914	return kvm_write_guest_offset_cached(kvm, ghc, data, 0, len);
2915}
2916EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
2917
2918int kvm_read_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2919				 void *data, unsigned int offset,
2920				 unsigned long len)
2921{
2922	struct kvm_memslots *slots = kvm_memslots(kvm);
2923	int r;
2924	gpa_t gpa = ghc->gpa + offset;
2925
2926	BUG_ON(len + offset > ghc->len);
 
 
 
2927
2928	if (slots->generation != ghc->generation) {
2929		if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
2930			return -EFAULT;
2931	}
2932
2933	if (kvm_is_error_hva(ghc->hva))
2934		return -EFAULT;
2935
2936	if (unlikely(!ghc->memslot))
2937		return kvm_read_guest(kvm, gpa, data, len);
2938
2939	r = __copy_from_user(data, (void __user *)ghc->hva + offset, len);
2940	if (r)
2941		return -EFAULT;
2942
2943	return 0;
2944}
2945EXPORT_SYMBOL_GPL(kvm_read_guest_offset_cached);
2946
2947int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2948			  void *data, unsigned long len)
2949{
2950	return kvm_read_guest_offset_cached(kvm, ghc, data, 0, len);
 
 
2951}
2952EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
2953
2954int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
2955{
2956	const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
2957	gfn_t gfn = gpa >> PAGE_SHIFT;
2958	int seg;
2959	int offset = offset_in_page(gpa);
2960	int ret;
2961
2962	while ((seg = next_segment(len, offset)) != 0) {
2963		ret = kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
2964		if (ret < 0)
2965			return ret;
2966		offset = 0;
2967		len -= seg;
2968		++gfn;
2969	}
2970	return 0;
2971}
2972EXPORT_SYMBOL_GPL(kvm_clear_guest);
2973
2974void mark_page_dirty_in_slot(struct kvm *kvm,
2975			     struct kvm_memory_slot *memslot,
2976		 	     gfn_t gfn)
2977{
2978	if (memslot && kvm_slot_dirty_track_enabled(memslot)) {
2979		unsigned long rel_gfn = gfn - memslot->base_gfn;
2980		u32 slot = (memslot->as_id << 16) | memslot->id;
2981
2982		if (kvm->dirty_ring_size)
2983			kvm_dirty_ring_push(kvm_dirty_ring_get(kvm),
2984					    slot, rel_gfn);
2985		else
2986			set_bit_le(rel_gfn, memslot->dirty_bitmap);
2987	}
2988}
2989EXPORT_SYMBOL_GPL(mark_page_dirty_in_slot);
2990
2991void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
2992{
2993	struct kvm_memory_slot *memslot;
2994
2995	memslot = gfn_to_memslot(kvm, gfn);
2996	mark_page_dirty_in_slot(kvm, memslot, gfn);
2997}
2998EXPORT_SYMBOL_GPL(mark_page_dirty);
2999
3000void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
3001{
3002	struct kvm_memory_slot *memslot;
3003
3004	memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
3005	mark_page_dirty_in_slot(vcpu->kvm, memslot, gfn);
3006}
3007EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
3008
3009void kvm_sigset_activate(struct kvm_vcpu *vcpu)
3010{
3011	if (!vcpu->sigset_active)
3012		return;
3013
3014	/*
3015	 * This does a lockless modification of ->real_blocked, which is fine
3016	 * because, only current can change ->real_blocked and all readers of
3017	 * ->real_blocked don't care as long ->real_blocked is always a subset
3018	 * of ->blocked.
3019	 */
3020	sigprocmask(SIG_SETMASK, &vcpu->sigset, &current->real_blocked);
3021}
3022
3023void kvm_sigset_deactivate(struct kvm_vcpu *vcpu)
3024{
3025	if (!vcpu->sigset_active)
3026		return;
3027
3028	sigprocmask(SIG_SETMASK, &current->real_blocked, NULL);
3029	sigemptyset(&current->real_blocked);
3030}
3031
3032static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
3033{
3034	unsigned int old, val, grow, grow_start;
3035
3036	old = val = vcpu->halt_poll_ns;
3037	grow_start = READ_ONCE(halt_poll_ns_grow_start);
3038	grow = READ_ONCE(halt_poll_ns_grow);
3039	if (!grow)
3040		goto out;
3041
3042	val *= grow;
3043	if (val < grow_start)
3044		val = grow_start;
3045
3046	if (val > vcpu->kvm->max_halt_poll_ns)
3047		val = vcpu->kvm->max_halt_poll_ns;
3048
3049	vcpu->halt_poll_ns = val;
3050out:
3051	trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
3052}
3053
3054static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
3055{
3056	unsigned int old, val, shrink, grow_start;
3057
3058	old = val = vcpu->halt_poll_ns;
3059	shrink = READ_ONCE(halt_poll_ns_shrink);
3060	grow_start = READ_ONCE(halt_poll_ns_grow_start);
3061	if (shrink == 0)
3062		val = 0;
3063	else
3064		val /= shrink;
3065
3066	if (val < grow_start)
3067		val = 0;
3068
3069	vcpu->halt_poll_ns = val;
3070	trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
3071}
3072
3073static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
3074{
3075	int ret = -EINTR;
3076	int idx = srcu_read_lock(&vcpu->kvm->srcu);
3077
3078	if (kvm_arch_vcpu_runnable(vcpu)) {
3079		kvm_make_request(KVM_REQ_UNHALT, vcpu);
3080		goto out;
3081	}
3082	if (kvm_cpu_has_pending_timer(vcpu))
3083		goto out;
3084	if (signal_pending(current))
3085		goto out;
3086	if (kvm_check_request(KVM_REQ_UNBLOCK, vcpu))
3087		goto out;
3088
3089	ret = 0;
3090out:
3091	srcu_read_unlock(&vcpu->kvm->srcu, idx);
3092	return ret;
3093}
3094
3095static inline void
3096update_halt_poll_stats(struct kvm_vcpu *vcpu, u64 poll_ns, bool waited)
3097{
3098	if (waited)
3099		vcpu->stat.generic.halt_poll_fail_ns += poll_ns;
3100	else
3101		vcpu->stat.generic.halt_poll_success_ns += poll_ns;
3102}
3103
3104/*
3105 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
3106 */
3107void kvm_vcpu_block(struct kvm_vcpu *vcpu)
3108{
3109	ktime_t start, cur, poll_end;
 
3110	bool waited = false;
3111	u64 block_ns;
3112
3113	kvm_arch_vcpu_blocking(vcpu);
3114
3115	start = cur = poll_end = ktime_get();
3116	if (vcpu->halt_poll_ns && !kvm_arch_no_poll(vcpu)) {
3117		ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
3118
3119		++vcpu->stat.generic.halt_attempted_poll;
3120		do {
3121			/*
3122			 * This sets KVM_REQ_UNHALT if an interrupt
3123			 * arrives.
3124			 */
3125			if (kvm_vcpu_check_block(vcpu) < 0) {
3126				++vcpu->stat.generic.halt_successful_poll;
3127				if (!vcpu_valid_wakeup(vcpu))
3128					++vcpu->stat.generic.halt_poll_invalid;
3129				goto out;
3130			}
3131			cpu_relax();
3132			poll_end = cur = ktime_get();
3133		} while (kvm_vcpu_can_poll(cur, stop));
3134	}
3135
3136	prepare_to_rcuwait(&vcpu->wait);
 
3137	for (;;) {
3138		set_current_state(TASK_INTERRUPTIBLE);
3139
3140		if (kvm_vcpu_check_block(vcpu) < 0)
3141			break;
3142
3143		waited = true;
3144		schedule();
3145	}
3146	finish_rcuwait(&vcpu->wait);
 
3147	cur = ktime_get();
 
 
3148out:
3149	kvm_arch_vcpu_unblocking(vcpu);
3150	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
3151
3152	update_halt_poll_stats(
3153		vcpu, ktime_to_ns(ktime_sub(poll_end, start)), waited);
3154
3155	if (!kvm_arch_no_poll(vcpu)) {
3156		if (!vcpu_valid_wakeup(vcpu)) {
3157			shrink_halt_poll_ns(vcpu);
3158		} else if (vcpu->kvm->max_halt_poll_ns) {
3159			if (block_ns <= vcpu->halt_poll_ns)
3160				;
3161			/* we had a long block, shrink polling */
3162			else if (vcpu->halt_poll_ns &&
3163					block_ns > vcpu->kvm->max_halt_poll_ns)
3164				shrink_halt_poll_ns(vcpu);
3165			/* we had a short halt and our poll time is too small */
3166			else if (vcpu->halt_poll_ns < vcpu->kvm->max_halt_poll_ns &&
3167					block_ns < vcpu->kvm->max_halt_poll_ns)
3168				grow_halt_poll_ns(vcpu);
3169		} else {
3170			vcpu->halt_poll_ns = 0;
3171		}
3172	}
3173
3174	trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu));
3175	kvm_arch_vcpu_block_finish(vcpu);
3176}
3177EXPORT_SYMBOL_GPL(kvm_vcpu_block);
3178
3179bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
3180{
3181	struct rcuwait *waitp;
3182
3183	waitp = kvm_arch_vcpu_get_wait(vcpu);
3184	if (rcuwait_wake_up(waitp)) {
3185		WRITE_ONCE(vcpu->ready, true);
3186		++vcpu->stat.generic.halt_wakeup;
3187		return true;
3188	}
3189
3190	return false;
3191}
3192EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);
3193
3194#ifndef CONFIG_S390
3195/*
3196 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
3197 */
3198void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
3199{
3200	int me;
3201	int cpu = vcpu->cpu;
 
3202
3203	if (kvm_vcpu_wake_up(vcpu))
3204		return;
 
 
 
3205
3206	me = get_cpu();
3207	if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
3208		if (kvm_arch_vcpu_should_kick(vcpu))
3209			smp_send_reschedule(cpu);
3210	put_cpu();
3211}
3212EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
3213#endif /* !CONFIG_S390 */
3214
3215int kvm_vcpu_yield_to(struct kvm_vcpu *target)
3216{
3217	struct pid *pid;
3218	struct task_struct *task = NULL;
3219	int ret = 0;
3220
3221	rcu_read_lock();
3222	pid = rcu_dereference(target->pid);
3223	if (pid)
3224		task = get_pid_task(pid, PIDTYPE_PID);
3225	rcu_read_unlock();
3226	if (!task)
3227		return ret;
3228	ret = yield_to(task, 1);
3229	put_task_struct(task);
3230
3231	return ret;
3232}
3233EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
3234
3235/*
3236 * Helper that checks whether a VCPU is eligible for directed yield.
3237 * Most eligible candidate to yield is decided by following heuristics:
3238 *
3239 *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
3240 *  (preempted lock holder), indicated by @in_spin_loop.
3241 *  Set at the beginning and cleared at the end of interception/PLE handler.
3242 *
3243 *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
3244 *  chance last time (mostly it has become eligible now since we have probably
3245 *  yielded to lockholder in last iteration. This is done by toggling
3246 *  @dy_eligible each time a VCPU checked for eligibility.)
3247 *
3248 *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
3249 *  to preempted lock-holder could result in wrong VCPU selection and CPU
3250 *  burning. Giving priority for a potential lock-holder increases lock
3251 *  progress.
3252 *
3253 *  Since algorithm is based on heuristics, accessing another VCPU data without
3254 *  locking does not harm. It may result in trying to yield to  same VCPU, fail
3255 *  and continue with next VCPU and so on.
3256 */
3257static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
3258{
3259#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
3260	bool eligible;
3261
3262	eligible = !vcpu->spin_loop.in_spin_loop ||
3263		    vcpu->spin_loop.dy_eligible;
3264
3265	if (vcpu->spin_loop.in_spin_loop)
3266		kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
3267
3268	return eligible;
3269#else
3270	return true;
3271#endif
3272}
3273
3274/*
3275 * Unlike kvm_arch_vcpu_runnable, this function is called outside
3276 * a vcpu_load/vcpu_put pair.  However, for most architectures
3277 * kvm_arch_vcpu_runnable does not require vcpu_load.
3278 */
3279bool __weak kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
3280{
3281	return kvm_arch_vcpu_runnable(vcpu);
3282}
3283
3284static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu)
3285{
3286	if (kvm_arch_dy_runnable(vcpu))
3287		return true;
3288
3289#ifdef CONFIG_KVM_ASYNC_PF
3290	if (!list_empty_careful(&vcpu->async_pf.done))
3291		return true;
3292#endif
3293
3294	return false;
3295}
3296
3297bool __weak kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu)
3298{
3299	return false;
3300}
3301
3302void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
3303{
3304	struct kvm *kvm = me->kvm;
3305	struct kvm_vcpu *vcpu;
3306	int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
3307	int yielded = 0;
3308	int try = 3;
3309	int pass;
3310	int i;
3311
3312	kvm_vcpu_set_in_spin_loop(me, true);
3313	/*
3314	 * We boost the priority of a VCPU that is runnable but not
3315	 * currently running, because it got preempted by something
3316	 * else and called schedule in __vcpu_run.  Hopefully that
3317	 * VCPU is holding the lock that we need and will release it.
3318	 * We approximate round-robin by starting at the last boosted VCPU.
3319	 */
3320	for (pass = 0; pass < 2 && !yielded && try; pass++) {
3321		kvm_for_each_vcpu(i, vcpu, kvm) {
3322			if (!pass && i <= last_boosted_vcpu) {
3323				i = last_boosted_vcpu;
3324				continue;
3325			} else if (pass && i > last_boosted_vcpu)
3326				break;
3327			if (!READ_ONCE(vcpu->ready))
3328				continue;
3329			if (vcpu == me)
3330				continue;
3331			if (rcuwait_active(&vcpu->wait) &&
3332			    !vcpu_dy_runnable(vcpu))
3333				continue;
3334			if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode &&
3335			    !kvm_arch_dy_has_pending_interrupt(vcpu) &&
3336			    !kvm_arch_vcpu_in_kernel(vcpu))
3337				continue;
3338			if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
3339				continue;
3340
3341			yielded = kvm_vcpu_yield_to(vcpu);
3342			if (yielded > 0) {
3343				kvm->last_boosted_vcpu = i;
3344				break;
3345			} else if (yielded < 0) {
3346				try--;
3347				if (!try)
3348					break;
3349			}
3350		}
3351	}
3352	kvm_vcpu_set_in_spin_loop(me, false);
3353
3354	/* Ensure vcpu is not eligible during next spinloop */
3355	kvm_vcpu_set_dy_eligible(me, false);
3356}
3357EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
3358
3359static bool kvm_page_in_dirty_ring(struct kvm *kvm, unsigned long pgoff)
3360{
3361#if KVM_DIRTY_LOG_PAGE_OFFSET > 0
3362	return (pgoff >= KVM_DIRTY_LOG_PAGE_OFFSET) &&
3363	    (pgoff < KVM_DIRTY_LOG_PAGE_OFFSET +
3364	     kvm->dirty_ring_size / PAGE_SIZE);
3365#else
3366	return false;
3367#endif
3368}
3369
3370static vm_fault_t kvm_vcpu_fault(struct vm_fault *vmf)
3371{
3372	struct kvm_vcpu *vcpu = vmf->vma->vm_file->private_data;
3373	struct page *page;
3374
3375	if (vmf->pgoff == 0)
3376		page = virt_to_page(vcpu->run);
3377#ifdef CONFIG_X86
3378	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
3379		page = virt_to_page(vcpu->arch.pio_data);
3380#endif
3381#ifdef CONFIG_KVM_MMIO
3382	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
3383		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
3384#endif
3385	else if (kvm_page_in_dirty_ring(vcpu->kvm, vmf->pgoff))
3386		page = kvm_dirty_ring_get_page(
3387		    &vcpu->dirty_ring,
3388		    vmf->pgoff - KVM_DIRTY_LOG_PAGE_OFFSET);
3389	else
3390		return kvm_arch_vcpu_fault(vcpu, vmf);
3391	get_page(page);
3392	vmf->page = page;
3393	return 0;
3394}
3395
3396static const struct vm_operations_struct kvm_vcpu_vm_ops = {
3397	.fault = kvm_vcpu_fault,
3398};
3399
3400static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
3401{
3402	struct kvm_vcpu *vcpu = file->private_data;
3403	unsigned long pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
3404
3405	if ((kvm_page_in_dirty_ring(vcpu->kvm, vma->vm_pgoff) ||
3406	     kvm_page_in_dirty_ring(vcpu->kvm, vma->vm_pgoff + pages - 1)) &&
3407	    ((vma->vm_flags & VM_EXEC) || !(vma->vm_flags & VM_SHARED)))
3408		return -EINVAL;
3409
3410	vma->vm_ops = &kvm_vcpu_vm_ops;
3411	return 0;
3412}
3413
3414static int kvm_vcpu_release(struct inode *inode, struct file *filp)
3415{
3416	struct kvm_vcpu *vcpu = filp->private_data;
3417
3418	kvm_put_kvm(vcpu->kvm);
3419	return 0;
3420}
3421
3422static struct file_operations kvm_vcpu_fops = {
3423	.release        = kvm_vcpu_release,
3424	.unlocked_ioctl = kvm_vcpu_ioctl,
 
 
 
3425	.mmap           = kvm_vcpu_mmap,
3426	.llseek		= noop_llseek,
3427	KVM_COMPAT(kvm_vcpu_compat_ioctl),
3428};
3429
3430/*
3431 * Allocates an inode for the vcpu.
3432 */
3433static int create_vcpu_fd(struct kvm_vcpu *vcpu)
3434{
3435	char name[8 + 1 + ITOA_MAX_LEN + 1];
3436
3437	snprintf(name, sizeof(name), "kvm-vcpu:%d", vcpu->vcpu_id);
3438	return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
3439}
3440
3441static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
3442{
3443#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
3444	struct dentry *debugfs_dentry;
3445	char dir_name[ITOA_MAX_LEN * 2];
3446
3447	if (!debugfs_initialized())
3448		return;
3449
3450	snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
3451	debugfs_dentry = debugfs_create_dir(dir_name,
3452					    vcpu->kvm->debugfs_dentry);
3453
3454	kvm_arch_create_vcpu_debugfs(vcpu, debugfs_dentry);
3455#endif
3456}
3457
3458/*
3459 * Creates some virtual cpus.  Good luck creating more than one.
3460 */
3461static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
3462{
3463	int r;
3464	struct kvm_vcpu *vcpu;
3465	struct page *page;
3466
3467	if (id >= KVM_MAX_VCPU_ID)
3468		return -EINVAL;
3469
3470	mutex_lock(&kvm->lock);
3471	if (kvm->created_vcpus == KVM_MAX_VCPUS) {
3472		mutex_unlock(&kvm->lock);
3473		return -EINVAL;
3474	}
3475
3476	kvm->created_vcpus++;
3477	mutex_unlock(&kvm->lock);
3478
3479	r = kvm_arch_vcpu_precreate(kvm, id);
3480	if (r)
3481		goto vcpu_decrement;
3482
3483	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT);
3484	if (!vcpu) {
3485		r = -ENOMEM;
3486		goto vcpu_decrement;
3487	}
3488
3489	BUILD_BUG_ON(sizeof(struct kvm_run) > PAGE_SIZE);
3490	page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
3491	if (!page) {
3492		r = -ENOMEM;
3493		goto vcpu_free;
3494	}
3495	vcpu->run = page_address(page);
3496
3497	kvm_vcpu_init(vcpu, kvm, id);
3498
3499	r = kvm_arch_vcpu_create(vcpu);
3500	if (r)
3501		goto vcpu_free_run_page;
3502
3503	if (kvm->dirty_ring_size) {
3504		r = kvm_dirty_ring_alloc(&vcpu->dirty_ring,
3505					 id, kvm->dirty_ring_size);
3506		if (r)
3507			goto arch_vcpu_destroy;
3508	}
3509
3510	mutex_lock(&kvm->lock);
3511	if (kvm_get_vcpu_by_id(kvm, id)) {
3512		r = -EEXIST;
3513		goto unlock_vcpu_destroy;
3514	}
3515
3516	vcpu->vcpu_idx = atomic_read(&kvm->online_vcpus);
3517	BUG_ON(kvm->vcpus[vcpu->vcpu_idx]);
3518
3519	/* Fill the stats id string for the vcpu */
3520	snprintf(vcpu->stats_id, sizeof(vcpu->stats_id), "kvm-%d/vcpu-%d",
3521		 task_pid_nr(current), id);
3522
3523	/* Now it's all set up, let userspace reach it */
3524	kvm_get_kvm(kvm);
3525	r = create_vcpu_fd(vcpu);
3526	if (r < 0) {
3527		kvm_put_kvm_no_destroy(kvm);
3528		goto unlock_vcpu_destroy;
3529	}
3530
3531	kvm->vcpus[vcpu->vcpu_idx] = vcpu;
3532
3533	/*
3534	 * Pairs with smp_rmb() in kvm_get_vcpu.  Write kvm->vcpus
3535	 * before kvm->online_vcpu's incremented value.
3536	 */
3537	smp_wmb();
3538	atomic_inc(&kvm->online_vcpus);
3539
3540	mutex_unlock(&kvm->lock);
3541	kvm_arch_vcpu_postcreate(vcpu);
3542	kvm_create_vcpu_debugfs(vcpu);
3543	return r;
3544
3545unlock_vcpu_destroy:
3546	mutex_unlock(&kvm->lock);
3547	kvm_dirty_ring_free(&vcpu->dirty_ring);
3548arch_vcpu_destroy:
3549	kvm_arch_vcpu_destroy(vcpu);
3550vcpu_free_run_page:
3551	free_page((unsigned long)vcpu->run);
3552vcpu_free:
3553	kmem_cache_free(kvm_vcpu_cache, vcpu);
3554vcpu_decrement:
3555	mutex_lock(&kvm->lock);
3556	kvm->created_vcpus--;
3557	mutex_unlock(&kvm->lock);
3558	return r;
3559}
3560
3561static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
3562{
3563	if (sigset) {
3564		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
3565		vcpu->sigset_active = 1;
3566		vcpu->sigset = *sigset;
3567	} else
3568		vcpu->sigset_active = 0;
3569	return 0;
3570}
3571
3572static ssize_t kvm_vcpu_stats_read(struct file *file, char __user *user_buffer,
3573			      size_t size, loff_t *offset)
3574{
3575	struct kvm_vcpu *vcpu = file->private_data;
3576
3577	return kvm_stats_read(vcpu->stats_id, &kvm_vcpu_stats_header,
3578			&kvm_vcpu_stats_desc[0], &vcpu->stat,
3579			sizeof(vcpu->stat), user_buffer, size, offset);
3580}
3581
3582static const struct file_operations kvm_vcpu_stats_fops = {
3583	.read = kvm_vcpu_stats_read,
3584	.llseek = noop_llseek,
3585};
3586
3587static int kvm_vcpu_ioctl_get_stats_fd(struct kvm_vcpu *vcpu)
3588{
3589	int fd;
3590	struct file *file;
3591	char name[15 + ITOA_MAX_LEN + 1];
3592
3593	snprintf(name, sizeof(name), "kvm-vcpu-stats:%d", vcpu->vcpu_id);
3594
3595	fd = get_unused_fd_flags(O_CLOEXEC);
3596	if (fd < 0)
3597		return fd;
3598
3599	file = anon_inode_getfile(name, &kvm_vcpu_stats_fops, vcpu, O_RDONLY);
3600	if (IS_ERR(file)) {
3601		put_unused_fd(fd);
3602		return PTR_ERR(file);
3603	}
3604	file->f_mode |= FMODE_PREAD;
3605	fd_install(fd, file);
3606
3607	return fd;
3608}
3609
3610static long kvm_vcpu_ioctl(struct file *filp,
3611			   unsigned int ioctl, unsigned long arg)
3612{
3613	struct kvm_vcpu *vcpu = filp->private_data;
3614	void __user *argp = (void __user *)arg;
3615	int r;
3616	struct kvm_fpu *fpu = NULL;
3617	struct kvm_sregs *kvm_sregs = NULL;
3618
3619	if (vcpu->kvm->mm != current->mm)
3620		return -EIO;
3621
3622	if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
3623		return -EINVAL;
3624
 
3625	/*
3626	 * Some architectures have vcpu ioctls that are asynchronous to vcpu
3627	 * execution; mutex_lock() would break them.
3628	 */
3629	r = kvm_arch_vcpu_async_ioctl(filp, ioctl, arg);
3630	if (r != -ENOIOCTLCMD)
 
 
 
 
 
3631		return r;
3632
3633	if (mutex_lock_killable(&vcpu->mutex))
3634		return -EINTR;
3635	switch (ioctl) {
3636	case KVM_RUN: {
3637		struct pid *oldpid;
3638		r = -EINVAL;
3639		if (arg)
3640			goto out;
3641		oldpid = rcu_access_pointer(vcpu->pid);
3642		if (unlikely(oldpid != task_pid(current))) {
3643			/* The thread running this VCPU changed. */
3644			struct pid *newpid;
3645
3646			r = kvm_arch_vcpu_run_pid_change(vcpu);
3647			if (r)
3648				break;
3649
3650			newpid = get_task_pid(current, PIDTYPE_PID);
3651			rcu_assign_pointer(vcpu->pid, newpid);
3652			if (oldpid)
3653				synchronize_rcu();
3654			put_pid(oldpid);
3655		}
3656		r = kvm_arch_vcpu_ioctl_run(vcpu);
3657		trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
3658		break;
3659	}
3660	case KVM_GET_REGS: {
3661		struct kvm_regs *kvm_regs;
3662
3663		r = -ENOMEM;
3664		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL_ACCOUNT);
3665		if (!kvm_regs)
3666			goto out;
3667		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
3668		if (r)
3669			goto out_free1;
3670		r = -EFAULT;
3671		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
3672			goto out_free1;
3673		r = 0;
3674out_free1:
3675		kfree(kvm_regs);
3676		break;
3677	}
3678	case KVM_SET_REGS: {
3679		struct kvm_regs *kvm_regs;
3680
 
3681		kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
3682		if (IS_ERR(kvm_regs)) {
3683			r = PTR_ERR(kvm_regs);
3684			goto out;
3685		}
3686		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
3687		kfree(kvm_regs);
3688		break;
3689	}
3690	case KVM_GET_SREGS: {
3691		kvm_sregs = kzalloc(sizeof(struct kvm_sregs),
3692				    GFP_KERNEL_ACCOUNT);
3693		r = -ENOMEM;
3694		if (!kvm_sregs)
3695			goto out;
3696		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
3697		if (r)
3698			goto out;
3699		r = -EFAULT;
3700		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
3701			goto out;
3702		r = 0;
3703		break;
3704	}
3705	case KVM_SET_SREGS: {
3706		kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
3707		if (IS_ERR(kvm_sregs)) {
3708			r = PTR_ERR(kvm_sregs);
3709			kvm_sregs = NULL;
3710			goto out;
3711		}
3712		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
3713		break;
3714	}
3715	case KVM_GET_MP_STATE: {
3716		struct kvm_mp_state mp_state;
3717
3718		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
3719		if (r)
3720			goto out;
3721		r = -EFAULT;
3722		if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
3723			goto out;
3724		r = 0;
3725		break;
3726	}
3727	case KVM_SET_MP_STATE: {
3728		struct kvm_mp_state mp_state;
3729
3730		r = -EFAULT;
3731		if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
3732			goto out;
3733		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
3734		break;
3735	}
3736	case KVM_TRANSLATE: {
3737		struct kvm_translation tr;
3738
3739		r = -EFAULT;
3740		if (copy_from_user(&tr, argp, sizeof(tr)))
3741			goto out;
3742		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
3743		if (r)
3744			goto out;
3745		r = -EFAULT;
3746		if (copy_to_user(argp, &tr, sizeof(tr)))
3747			goto out;
3748		r = 0;
3749		break;
3750	}
3751	case KVM_SET_GUEST_DEBUG: {
3752		struct kvm_guest_debug dbg;
3753
3754		r = -EFAULT;
3755		if (copy_from_user(&dbg, argp, sizeof(dbg)))
3756			goto out;
3757		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
3758		break;
3759	}
3760	case KVM_SET_SIGNAL_MASK: {
3761		struct kvm_signal_mask __user *sigmask_arg = argp;
3762		struct kvm_signal_mask kvm_sigmask;
3763		sigset_t sigset, *p;
3764
3765		p = NULL;
3766		if (argp) {
3767			r = -EFAULT;
3768			if (copy_from_user(&kvm_sigmask, argp,
3769					   sizeof(kvm_sigmask)))
3770				goto out;
3771			r = -EINVAL;
3772			if (kvm_sigmask.len != sizeof(sigset))
3773				goto out;
3774			r = -EFAULT;
3775			if (copy_from_user(&sigset, sigmask_arg->sigset,
3776					   sizeof(sigset)))
3777				goto out;
3778			p = &sigset;
3779		}
3780		r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
3781		break;
3782	}
3783	case KVM_GET_FPU: {
3784		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL_ACCOUNT);
3785		r = -ENOMEM;
3786		if (!fpu)
3787			goto out;
3788		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
3789		if (r)
3790			goto out;
3791		r = -EFAULT;
3792		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
3793			goto out;
3794		r = 0;
3795		break;
3796	}
3797	case KVM_SET_FPU: {
3798		fpu = memdup_user(argp, sizeof(*fpu));
3799		if (IS_ERR(fpu)) {
3800			r = PTR_ERR(fpu);
3801			fpu = NULL;
3802			goto out;
3803		}
3804		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
3805		break;
3806	}
3807	case KVM_GET_STATS_FD: {
3808		r = kvm_vcpu_ioctl_get_stats_fd(vcpu);
3809		break;
3810	}
3811	default:
3812		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
3813	}
3814out:
3815	mutex_unlock(&vcpu->mutex);
3816	kfree(fpu);
3817	kfree(kvm_sregs);
3818	return r;
3819}
3820
3821#ifdef CONFIG_KVM_COMPAT
3822static long kvm_vcpu_compat_ioctl(struct file *filp,
3823				  unsigned int ioctl, unsigned long arg)
3824{
3825	struct kvm_vcpu *vcpu = filp->private_data;
3826	void __user *argp = compat_ptr(arg);
3827	int r;
3828
3829	if (vcpu->kvm->mm != current->mm)
3830		return -EIO;
3831
3832	switch (ioctl) {
3833	case KVM_SET_SIGNAL_MASK: {
3834		struct kvm_signal_mask __user *sigmask_arg = argp;
3835		struct kvm_signal_mask kvm_sigmask;
 
3836		sigset_t sigset;
3837
3838		if (argp) {
3839			r = -EFAULT;
3840			if (copy_from_user(&kvm_sigmask, argp,
3841					   sizeof(kvm_sigmask)))
3842				goto out;
3843			r = -EINVAL;
3844			if (kvm_sigmask.len != sizeof(compat_sigset_t))
3845				goto out;
3846			r = -EFAULT;
3847			if (get_compat_sigset(&sigset,
3848					      (compat_sigset_t __user *)sigmask_arg->sigset))
3849				goto out;
 
3850			r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
3851		} else
3852			r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
3853		break;
3854	}
3855	default:
3856		r = kvm_vcpu_ioctl(filp, ioctl, arg);
3857	}
3858
3859out:
3860	return r;
3861}
3862#endif
3863
3864static int kvm_device_mmap(struct file *filp, struct vm_area_struct *vma)
3865{
3866	struct kvm_device *dev = filp->private_data;
3867
3868	if (dev->ops->mmap)
3869		return dev->ops->mmap(dev, vma);
3870
3871	return -ENODEV;
3872}
3873
3874static int kvm_device_ioctl_attr(struct kvm_device *dev,
3875				 int (*accessor)(struct kvm_device *dev,
3876						 struct kvm_device_attr *attr),
3877				 unsigned long arg)
3878{
3879	struct kvm_device_attr attr;
3880
3881	if (!accessor)
3882		return -EPERM;
3883
3884	if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
3885		return -EFAULT;
3886
3887	return accessor(dev, &attr);
3888}
3889
3890static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
3891			     unsigned long arg)
3892{
3893	struct kvm_device *dev = filp->private_data;
3894
3895	if (dev->kvm->mm != current->mm)
3896		return -EIO;
3897
3898	switch (ioctl) {
3899	case KVM_SET_DEVICE_ATTR:
3900		return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
3901	case KVM_GET_DEVICE_ATTR:
3902		return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
3903	case KVM_HAS_DEVICE_ATTR:
3904		return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
3905	default:
3906		if (dev->ops->ioctl)
3907			return dev->ops->ioctl(dev, ioctl, arg);
3908
3909		return -ENOTTY;
3910	}
3911}
3912
3913static int kvm_device_release(struct inode *inode, struct file *filp)
3914{
3915	struct kvm_device *dev = filp->private_data;
3916	struct kvm *kvm = dev->kvm;
3917
3918	if (dev->ops->release) {
3919		mutex_lock(&kvm->lock);
3920		list_del(&dev->vm_node);
3921		dev->ops->release(dev);
3922		mutex_unlock(&kvm->lock);
3923	}
3924
3925	kvm_put_kvm(kvm);
3926	return 0;
3927}
3928
3929static const struct file_operations kvm_device_fops = {
3930	.unlocked_ioctl = kvm_device_ioctl,
 
 
 
3931	.release = kvm_device_release,
3932	KVM_COMPAT(kvm_device_ioctl),
3933	.mmap = kvm_device_mmap,
3934};
3935
3936struct kvm_device *kvm_device_from_filp(struct file *filp)
3937{
3938	if (filp->f_op != &kvm_device_fops)
3939		return NULL;
3940
3941	return filp->private_data;
3942}
3943
3944static const struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
3945#ifdef CONFIG_KVM_MPIC
3946	[KVM_DEV_TYPE_FSL_MPIC_20]	= &kvm_mpic_ops,
3947	[KVM_DEV_TYPE_FSL_MPIC_42]	= &kvm_mpic_ops,
3948#endif
 
 
 
 
3949};
3950
3951int kvm_register_device_ops(const struct kvm_device_ops *ops, u32 type)
3952{
3953	if (type >= ARRAY_SIZE(kvm_device_ops_table))
3954		return -ENOSPC;
3955
3956	if (kvm_device_ops_table[type] != NULL)
3957		return -EEXIST;
3958
3959	kvm_device_ops_table[type] = ops;
3960	return 0;
3961}
3962
3963void kvm_unregister_device_ops(u32 type)
3964{
3965	if (kvm_device_ops_table[type] != NULL)
3966		kvm_device_ops_table[type] = NULL;
3967}
3968
3969static int kvm_ioctl_create_device(struct kvm *kvm,
3970				   struct kvm_create_device *cd)
3971{
3972	const struct kvm_device_ops *ops = NULL;
3973	struct kvm_device *dev;
3974	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
3975	int type;
3976	int ret;
3977
3978	if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
3979		return -ENODEV;
3980
3981	type = array_index_nospec(cd->type, ARRAY_SIZE(kvm_device_ops_table));
3982	ops = kvm_device_ops_table[type];
3983	if (ops == NULL)
3984		return -ENODEV;
3985
3986	if (test)
3987		return 0;
3988
3989	dev = kzalloc(sizeof(*dev), GFP_KERNEL_ACCOUNT);
3990	if (!dev)
3991		return -ENOMEM;
3992
3993	dev->ops = ops;
3994	dev->kvm = kvm;
3995
3996	mutex_lock(&kvm->lock);
3997	ret = ops->create(dev, type);
3998	if (ret < 0) {
3999		mutex_unlock(&kvm->lock);
4000		kfree(dev);
4001		return ret;
4002	}
4003	list_add(&dev->vm_node, &kvm->devices);
4004	mutex_unlock(&kvm->lock);
4005
4006	if (ops->init)
4007		ops->init(dev);
4008
4009	kvm_get_kvm(kvm);
4010	ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
4011	if (ret < 0) {
4012		kvm_put_kvm_no_destroy(kvm);
4013		mutex_lock(&kvm->lock);
4014		list_del(&dev->vm_node);
4015		mutex_unlock(&kvm->lock);
4016		ops->destroy(dev);
4017		return ret;
4018	}
4019
 
 
4020	cd->fd = ret;
4021	return 0;
4022}
4023
4024static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
4025{
4026	switch (arg) {
4027	case KVM_CAP_USER_MEMORY:
4028	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
4029	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
4030	case KVM_CAP_INTERNAL_ERROR_DATA:
4031#ifdef CONFIG_HAVE_KVM_MSI
4032	case KVM_CAP_SIGNAL_MSI:
4033#endif
4034#ifdef CONFIG_HAVE_KVM_IRQFD
4035	case KVM_CAP_IRQFD:
4036	case KVM_CAP_IRQFD_RESAMPLE:
4037#endif
4038	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
4039	case KVM_CAP_CHECK_EXTENSION_VM:
4040	case KVM_CAP_ENABLE_CAP_VM:
4041	case KVM_CAP_HALT_POLL:
4042		return 1;
4043#ifdef CONFIG_KVM_MMIO
4044	case KVM_CAP_COALESCED_MMIO:
4045		return KVM_COALESCED_MMIO_PAGE_OFFSET;
4046	case KVM_CAP_COALESCED_PIO:
4047		return 1;
4048#endif
4049#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
4050	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2:
4051		return KVM_DIRTY_LOG_MANUAL_CAPS;
4052#endif
4053#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
4054	case KVM_CAP_IRQ_ROUTING:
4055		return KVM_MAX_IRQ_ROUTES;
4056#endif
4057#if KVM_ADDRESS_SPACE_NUM > 1
4058	case KVM_CAP_MULTI_ADDRESS_SPACE:
4059		return KVM_ADDRESS_SPACE_NUM;
4060#endif
4061	case KVM_CAP_NR_MEMSLOTS:
4062		return KVM_USER_MEM_SLOTS;
4063	case KVM_CAP_DIRTY_LOG_RING:
4064#if KVM_DIRTY_LOG_PAGE_OFFSET > 0
4065		return KVM_DIRTY_RING_MAX_ENTRIES * sizeof(struct kvm_dirty_gfn);
4066#else
4067		return 0;
4068#endif
4069	case KVM_CAP_BINARY_STATS_FD:
4070		return 1;
4071	default:
4072		break;
4073	}
4074	return kvm_vm_ioctl_check_extension(kvm, arg);
4075}
4076
4077static int kvm_vm_ioctl_enable_dirty_log_ring(struct kvm *kvm, u32 size)
4078{
4079	int r;
4080
4081	if (!KVM_DIRTY_LOG_PAGE_OFFSET)
4082		return -EINVAL;
4083
4084	/* the size should be power of 2 */
4085	if (!size || (size & (size - 1)))
4086		return -EINVAL;
4087
4088	/* Should be bigger to keep the reserved entries, or a page */
4089	if (size < kvm_dirty_ring_get_rsvd_entries() *
4090	    sizeof(struct kvm_dirty_gfn) || size < PAGE_SIZE)
4091		return -EINVAL;
4092
4093	if (size > KVM_DIRTY_RING_MAX_ENTRIES *
4094	    sizeof(struct kvm_dirty_gfn))
4095		return -E2BIG;
4096
4097	/* We only allow it to set once */
4098	if (kvm->dirty_ring_size)
4099		return -EINVAL;
4100
4101	mutex_lock(&kvm->lock);
4102
4103	if (kvm->created_vcpus) {
4104		/* We don't allow to change this value after vcpu created */
4105		r = -EINVAL;
4106	} else {
4107		kvm->dirty_ring_size = size;
4108		r = 0;
4109	}
4110
4111	mutex_unlock(&kvm->lock);
4112	return r;
4113}
4114
4115static int kvm_vm_ioctl_reset_dirty_pages(struct kvm *kvm)
4116{
4117	int i;
4118	struct kvm_vcpu *vcpu;
4119	int cleared = 0;
4120
4121	if (!kvm->dirty_ring_size)
4122		return -EINVAL;
4123
4124	mutex_lock(&kvm->slots_lock);
4125
4126	kvm_for_each_vcpu(i, vcpu, kvm)
4127		cleared += kvm_dirty_ring_reset(vcpu->kvm, &vcpu->dirty_ring);
4128
4129	mutex_unlock(&kvm->slots_lock);
4130
4131	if (cleared)
4132		kvm_flush_remote_tlbs(kvm);
4133
4134	return cleared;
4135}
4136
4137int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
4138						  struct kvm_enable_cap *cap)
4139{
4140	return -EINVAL;
4141}
4142
4143static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
4144					   struct kvm_enable_cap *cap)
4145{
4146	switch (cap->cap) {
4147#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
4148	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2: {
4149		u64 allowed_options = KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE;
4150
4151		if (cap->args[0] & KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE)
4152			allowed_options = KVM_DIRTY_LOG_MANUAL_CAPS;
4153
4154		if (cap->flags || (cap->args[0] & ~allowed_options))
4155			return -EINVAL;
4156		kvm->manual_dirty_log_protect = cap->args[0];
4157		return 0;
4158	}
4159#endif
4160	case KVM_CAP_HALT_POLL: {
4161		if (cap->flags || cap->args[0] != (unsigned int)cap->args[0])
4162			return -EINVAL;
4163
4164		kvm->max_halt_poll_ns = cap->args[0];
4165		return 0;
4166	}
4167	case KVM_CAP_DIRTY_LOG_RING:
4168		return kvm_vm_ioctl_enable_dirty_log_ring(kvm, cap->args[0]);
4169	default:
4170		return kvm_vm_ioctl_enable_cap(kvm, cap);
4171	}
4172}
4173
4174static ssize_t kvm_vm_stats_read(struct file *file, char __user *user_buffer,
4175			      size_t size, loff_t *offset)
4176{
4177	struct kvm *kvm = file->private_data;
4178
4179	return kvm_stats_read(kvm->stats_id, &kvm_vm_stats_header,
4180				&kvm_vm_stats_desc[0], &kvm->stat,
4181				sizeof(kvm->stat), user_buffer, size, offset);
4182}
4183
4184static const struct file_operations kvm_vm_stats_fops = {
4185	.read = kvm_vm_stats_read,
4186	.llseek = noop_llseek,
4187};
4188
4189static int kvm_vm_ioctl_get_stats_fd(struct kvm *kvm)
4190{
4191	int fd;
4192	struct file *file;
4193
4194	fd = get_unused_fd_flags(O_CLOEXEC);
4195	if (fd < 0)
4196		return fd;
4197
4198	file = anon_inode_getfile("kvm-vm-stats",
4199			&kvm_vm_stats_fops, kvm, O_RDONLY);
4200	if (IS_ERR(file)) {
4201		put_unused_fd(fd);
4202		return PTR_ERR(file);
4203	}
4204	file->f_mode |= FMODE_PREAD;
4205	fd_install(fd, file);
4206
4207	return fd;
4208}
4209
4210static long kvm_vm_ioctl(struct file *filp,
4211			   unsigned int ioctl, unsigned long arg)
4212{
4213	struct kvm *kvm = filp->private_data;
4214	void __user *argp = (void __user *)arg;
4215	int r;
4216
4217	if (kvm->mm != current->mm)
4218		return -EIO;
4219	switch (ioctl) {
4220	case KVM_CREATE_VCPU:
4221		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
4222		break;
4223	case KVM_ENABLE_CAP: {
4224		struct kvm_enable_cap cap;
4225
4226		r = -EFAULT;
4227		if (copy_from_user(&cap, argp, sizeof(cap)))
4228			goto out;
4229		r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
4230		break;
4231	}
4232	case KVM_SET_USER_MEMORY_REGION: {
4233		struct kvm_userspace_memory_region kvm_userspace_mem;
4234
4235		r = -EFAULT;
4236		if (copy_from_user(&kvm_userspace_mem, argp,
4237						sizeof(kvm_userspace_mem)))
4238			goto out;
4239
4240		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
4241		break;
4242	}
4243	case KVM_GET_DIRTY_LOG: {
4244		struct kvm_dirty_log log;
4245
4246		r = -EFAULT;
4247		if (copy_from_user(&log, argp, sizeof(log)))
4248			goto out;
4249		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
4250		break;
4251	}
4252#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
4253	case KVM_CLEAR_DIRTY_LOG: {
4254		struct kvm_clear_dirty_log log;
4255
4256		r = -EFAULT;
4257		if (copy_from_user(&log, argp, sizeof(log)))
4258			goto out;
4259		r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
4260		break;
4261	}
4262#endif
4263#ifdef CONFIG_KVM_MMIO
4264	case KVM_REGISTER_COALESCED_MMIO: {
4265		struct kvm_coalesced_mmio_zone zone;
4266
4267		r = -EFAULT;
4268		if (copy_from_user(&zone, argp, sizeof(zone)))
4269			goto out;
4270		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
4271		break;
4272	}
4273	case KVM_UNREGISTER_COALESCED_MMIO: {
4274		struct kvm_coalesced_mmio_zone zone;
4275
4276		r = -EFAULT;
4277		if (copy_from_user(&zone, argp, sizeof(zone)))
4278			goto out;
4279		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
4280		break;
4281	}
4282#endif
4283	case KVM_IRQFD: {
4284		struct kvm_irqfd data;
4285
4286		r = -EFAULT;
4287		if (copy_from_user(&data, argp, sizeof(data)))
4288			goto out;
4289		r = kvm_irqfd(kvm, &data);
4290		break;
4291	}
4292	case KVM_IOEVENTFD: {
4293		struct kvm_ioeventfd data;
4294
4295		r = -EFAULT;
4296		if (copy_from_user(&data, argp, sizeof(data)))
4297			goto out;
4298		r = kvm_ioeventfd(kvm, &data);
4299		break;
4300	}
4301#ifdef CONFIG_HAVE_KVM_MSI
4302	case KVM_SIGNAL_MSI: {
4303		struct kvm_msi msi;
4304
4305		r = -EFAULT;
4306		if (copy_from_user(&msi, argp, sizeof(msi)))
4307			goto out;
4308		r = kvm_send_userspace_msi(kvm, &msi);
4309		break;
4310	}
4311#endif
4312#ifdef __KVM_HAVE_IRQ_LINE
4313	case KVM_IRQ_LINE_STATUS:
4314	case KVM_IRQ_LINE: {
4315		struct kvm_irq_level irq_event;
4316
4317		r = -EFAULT;
4318		if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
4319			goto out;
4320
4321		r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
4322					ioctl == KVM_IRQ_LINE_STATUS);
4323		if (r)
4324			goto out;
4325
4326		r = -EFAULT;
4327		if (ioctl == KVM_IRQ_LINE_STATUS) {
4328			if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
4329				goto out;
4330		}
4331
4332		r = 0;
4333		break;
4334	}
4335#endif
4336#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
4337	case KVM_SET_GSI_ROUTING: {
4338		struct kvm_irq_routing routing;
4339		struct kvm_irq_routing __user *urouting;
4340		struct kvm_irq_routing_entry *entries = NULL;
4341
4342		r = -EFAULT;
4343		if (copy_from_user(&routing, argp, sizeof(routing)))
4344			goto out;
4345		r = -EINVAL;
4346		if (!kvm_arch_can_set_irq_routing(kvm))
4347			goto out;
4348		if (routing.nr > KVM_MAX_IRQ_ROUTES)
4349			goto out;
4350		if (routing.flags)
 
 
4351			goto out;
4352		if (routing.nr) {
4353			urouting = argp;
4354			entries = vmemdup_user(urouting->entries,
4355					       array_size(sizeof(*entries),
4356							  routing.nr));
4357			if (IS_ERR(entries)) {
4358				r = PTR_ERR(entries);
4359				goto out;
4360			}
4361		}
4362		r = kvm_set_irq_routing(kvm, entries, routing.nr,
4363					routing.flags);
4364		kvfree(entries);
 
4365		break;
4366	}
4367#endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
4368	case KVM_CREATE_DEVICE: {
4369		struct kvm_create_device cd;
4370
4371		r = -EFAULT;
4372		if (copy_from_user(&cd, argp, sizeof(cd)))
4373			goto out;
4374
4375		r = kvm_ioctl_create_device(kvm, &cd);
4376		if (r)
4377			goto out;
4378
4379		r = -EFAULT;
4380		if (copy_to_user(argp, &cd, sizeof(cd)))
4381			goto out;
4382
4383		r = 0;
4384		break;
4385	}
4386	case KVM_CHECK_EXTENSION:
4387		r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
4388		break;
4389	case KVM_RESET_DIRTY_RINGS:
4390		r = kvm_vm_ioctl_reset_dirty_pages(kvm);
4391		break;
4392	case KVM_GET_STATS_FD:
4393		r = kvm_vm_ioctl_get_stats_fd(kvm);
4394		break;
4395	default:
4396		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
4397	}
4398out:
4399	return r;
4400}
4401
4402#ifdef CONFIG_KVM_COMPAT
4403struct compat_kvm_dirty_log {
4404	__u32 slot;
4405	__u32 padding1;
4406	union {
4407		compat_uptr_t dirty_bitmap; /* one bit per page */
4408		__u64 padding2;
4409	};
4410};
4411
4412struct compat_kvm_clear_dirty_log {
4413	__u32 slot;
4414	__u32 num_pages;
4415	__u64 first_page;
4416	union {
4417		compat_uptr_t dirty_bitmap; /* one bit per page */
4418		__u64 padding2;
4419	};
4420};
4421
4422static long kvm_vm_compat_ioctl(struct file *filp,
4423			   unsigned int ioctl, unsigned long arg)
4424{
4425	struct kvm *kvm = filp->private_data;
4426	int r;
4427
4428	if (kvm->mm != current->mm)
4429		return -EIO;
4430	switch (ioctl) {
4431#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
4432	case KVM_CLEAR_DIRTY_LOG: {
4433		struct compat_kvm_clear_dirty_log compat_log;
4434		struct kvm_clear_dirty_log log;
4435
4436		if (copy_from_user(&compat_log, (void __user *)arg,
4437				   sizeof(compat_log)))
4438			return -EFAULT;
4439		log.slot	 = compat_log.slot;
4440		log.num_pages	 = compat_log.num_pages;
4441		log.first_page	 = compat_log.first_page;
4442		log.padding2	 = compat_log.padding2;
4443		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
4444
4445		r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
4446		break;
4447	}
4448#endif
4449	case KVM_GET_DIRTY_LOG: {
4450		struct compat_kvm_dirty_log compat_log;
4451		struct kvm_dirty_log log;
4452
 
4453		if (copy_from_user(&compat_log, (void __user *)arg,
4454				   sizeof(compat_log)))
4455			return -EFAULT;
4456		log.slot	 = compat_log.slot;
4457		log.padding1	 = compat_log.padding1;
4458		log.padding2	 = compat_log.padding2;
4459		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
4460
4461		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
4462		break;
4463	}
4464	default:
4465		r = kvm_vm_ioctl(filp, ioctl, arg);
4466	}
 
 
4467	return r;
4468}
4469#endif
4470
4471static struct file_operations kvm_vm_fops = {
4472	.release        = kvm_vm_release,
4473	.unlocked_ioctl = kvm_vm_ioctl,
 
 
 
4474	.llseek		= noop_llseek,
4475	KVM_COMPAT(kvm_vm_compat_ioctl),
4476};
4477
4478bool file_is_kvm(struct file *file)
4479{
4480	return file && file->f_op == &kvm_vm_fops;
4481}
4482EXPORT_SYMBOL_GPL(file_is_kvm);
4483
4484static int kvm_dev_ioctl_create_vm(unsigned long type)
4485{
4486	int r;
4487	struct kvm *kvm;
4488	struct file *file;
4489
4490	kvm = kvm_create_vm(type);
4491	if (IS_ERR(kvm))
4492		return PTR_ERR(kvm);
4493#ifdef CONFIG_KVM_MMIO
4494	r = kvm_coalesced_mmio_init(kvm);
4495	if (r < 0)
4496		goto put_kvm;
 
 
4497#endif
4498	r = get_unused_fd_flags(O_CLOEXEC);
4499	if (r < 0)
4500		goto put_kvm;
4501
4502	snprintf(kvm->stats_id, sizeof(kvm->stats_id),
4503			"kvm-%d", task_pid_nr(current));
4504
4505	file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
4506	if (IS_ERR(file)) {
4507		put_unused_fd(r);
4508		r = PTR_ERR(file);
4509		goto put_kvm;
4510	}
4511
4512	/*
4513	 * Don't call kvm_put_kvm anymore at this point; file->f_op is
4514	 * already set, with ->release() being kvm_vm_release().  In error
4515	 * cases it will be called by the final fput(file) and will take
4516	 * care of doing kvm_put_kvm(kvm).
4517	 */
4518	if (kvm_create_vm_debugfs(kvm, r) < 0) {
4519		put_unused_fd(r);
4520		fput(file);
4521		return -ENOMEM;
4522	}
4523	kvm_uevent_notify_change(KVM_EVENT_CREATE_VM, kvm);
4524
4525	fd_install(r, file);
4526	return r;
4527
4528put_kvm:
4529	kvm_put_kvm(kvm);
4530	return r;
4531}
4532
4533static long kvm_dev_ioctl(struct file *filp,
4534			  unsigned int ioctl, unsigned long arg)
4535{
4536	long r = -EINVAL;
4537
4538	switch (ioctl) {
4539	case KVM_GET_API_VERSION:
4540		if (arg)
4541			goto out;
4542		r = KVM_API_VERSION;
4543		break;
4544	case KVM_CREATE_VM:
4545		r = kvm_dev_ioctl_create_vm(arg);
4546		break;
4547	case KVM_CHECK_EXTENSION:
4548		r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
4549		break;
4550	case KVM_GET_VCPU_MMAP_SIZE:
4551		if (arg)
4552			goto out;
4553		r = PAGE_SIZE;     /* struct kvm_run */
4554#ifdef CONFIG_X86
4555		r += PAGE_SIZE;    /* pio data page */
4556#endif
4557#ifdef CONFIG_KVM_MMIO
4558		r += PAGE_SIZE;    /* coalesced mmio ring page */
4559#endif
4560		break;
4561	case KVM_TRACE_ENABLE:
4562	case KVM_TRACE_PAUSE:
4563	case KVM_TRACE_DISABLE:
4564		r = -EOPNOTSUPP;
4565		break;
4566	default:
4567		return kvm_arch_dev_ioctl(filp, ioctl, arg);
4568	}
4569out:
4570	return r;
4571}
4572
4573static struct file_operations kvm_chardev_ops = {
4574	.unlocked_ioctl = kvm_dev_ioctl,
 
4575	.llseek		= noop_llseek,
4576	KVM_COMPAT(kvm_dev_ioctl),
4577};
4578
4579static struct miscdevice kvm_dev = {
4580	KVM_MINOR,
4581	"kvm",
4582	&kvm_chardev_ops,
4583};
4584
4585static void hardware_enable_nolock(void *junk)
4586{
4587	int cpu = raw_smp_processor_id();
4588	int r;
4589
4590	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
4591		return;
4592
4593	cpumask_set_cpu(cpu, cpus_hardware_enabled);
4594
4595	r = kvm_arch_hardware_enable();
4596
4597	if (r) {
4598		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
4599		atomic_inc(&hardware_enable_failed);
4600		pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
4601	}
4602}
4603
4604static int kvm_starting_cpu(unsigned int cpu)
4605{
4606	raw_spin_lock(&kvm_count_lock);
4607	if (kvm_usage_count)
4608		hardware_enable_nolock(NULL);
4609	raw_spin_unlock(&kvm_count_lock);
4610	return 0;
4611}
4612
4613static void hardware_disable_nolock(void *junk)
4614{
4615	int cpu = raw_smp_processor_id();
4616
4617	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
4618		return;
4619	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
4620	kvm_arch_hardware_disable();
4621}
4622
4623static int kvm_dying_cpu(unsigned int cpu)
4624{
4625	raw_spin_lock(&kvm_count_lock);
4626	if (kvm_usage_count)
4627		hardware_disable_nolock(NULL);
4628	raw_spin_unlock(&kvm_count_lock);
4629	return 0;
4630}
4631
4632static void hardware_disable_all_nolock(void)
4633{
4634	BUG_ON(!kvm_usage_count);
4635
4636	kvm_usage_count--;
4637	if (!kvm_usage_count)
4638		on_each_cpu(hardware_disable_nolock, NULL, 1);
4639}
4640
4641static void hardware_disable_all(void)
4642{
4643	raw_spin_lock(&kvm_count_lock);
4644	hardware_disable_all_nolock();
4645	raw_spin_unlock(&kvm_count_lock);
4646}
4647
4648static int hardware_enable_all(void)
4649{
4650	int r = 0;
4651
4652	raw_spin_lock(&kvm_count_lock);
4653
4654	kvm_usage_count++;
4655	if (kvm_usage_count == 1) {
4656		atomic_set(&hardware_enable_failed, 0);
4657		on_each_cpu(hardware_enable_nolock, NULL, 1);
4658
4659		if (atomic_read(&hardware_enable_failed)) {
4660			hardware_disable_all_nolock();
4661			r = -EBUSY;
4662		}
4663	}
4664
4665	raw_spin_unlock(&kvm_count_lock);
4666
4667	return r;
4668}
4669
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4670static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
4671		      void *v)
4672{
4673	/*
4674	 * Some (well, at least mine) BIOSes hang on reboot if
4675	 * in vmx root mode.
4676	 *
4677	 * And Intel TXT required VMX off for all cpu when system shutdown.
4678	 */
4679	pr_info("kvm: exiting hardware virtualization\n");
4680	kvm_rebooting = true;
4681	on_each_cpu(hardware_disable_nolock, NULL, 1);
4682	return NOTIFY_OK;
4683}
4684
4685static struct notifier_block kvm_reboot_notifier = {
4686	.notifier_call = kvm_reboot,
4687	.priority = 0,
4688};
4689
4690static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
4691{
4692	int i;
4693
4694	for (i = 0; i < bus->dev_count; i++) {
4695		struct kvm_io_device *pos = bus->range[i].dev;
4696
4697		kvm_iodevice_destructor(pos);
4698	}
4699	kfree(bus);
4700}
4701
4702static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
4703				 const struct kvm_io_range *r2)
4704{
4705	gpa_t addr1 = r1->addr;
4706	gpa_t addr2 = r2->addr;
4707
4708	if (addr1 < addr2)
4709		return -1;
4710
4711	/* If r2->len == 0, match the exact address.  If r2->len != 0,
4712	 * accept any overlapping write.  Any order is acceptable for
4713	 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
4714	 * we process all of them.
4715	 */
4716	if (r2->len) {
4717		addr1 += r1->len;
4718		addr2 += r2->len;
4719	}
4720
4721	if (addr1 > addr2)
4722		return 1;
4723
4724	return 0;
4725}
4726
4727static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
4728{
4729	return kvm_io_bus_cmp(p1, p2);
4730}
4731
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4732static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
4733			     gpa_t addr, int len)
4734{
4735	struct kvm_io_range *range, key;
4736	int off;
4737
4738	key = (struct kvm_io_range) {
4739		.addr = addr,
4740		.len = len,
4741	};
4742
4743	range = bsearch(&key, bus->range, bus->dev_count,
4744			sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
4745	if (range == NULL)
4746		return -ENOENT;
4747
4748	off = range - bus->range;
4749
4750	while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
4751		off--;
4752
4753	return off;
4754}
4755
4756static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
4757			      struct kvm_io_range *range, const void *val)
4758{
4759	int idx;
4760
4761	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
4762	if (idx < 0)
4763		return -EOPNOTSUPP;
4764
4765	while (idx < bus->dev_count &&
4766		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
4767		if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
4768					range->len, val))
4769			return idx;
4770		idx++;
4771	}
4772
4773	return -EOPNOTSUPP;
4774}
4775
4776/* kvm_io_bus_write - called under kvm->slots_lock */
4777int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
4778		     int len, const void *val)
4779{
4780	struct kvm_io_bus *bus;
4781	struct kvm_io_range range;
4782	int r;
4783
4784	range = (struct kvm_io_range) {
4785		.addr = addr,
4786		.len = len,
4787	};
4788
4789	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4790	if (!bus)
4791		return -ENOMEM;
4792	r = __kvm_io_bus_write(vcpu, bus, &range, val);
4793	return r < 0 ? r : 0;
4794}
4795EXPORT_SYMBOL_GPL(kvm_io_bus_write);
4796
4797/* kvm_io_bus_write_cookie - called under kvm->slots_lock */
4798int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
4799			    gpa_t addr, int len, const void *val, long cookie)
4800{
4801	struct kvm_io_bus *bus;
4802	struct kvm_io_range range;
4803
4804	range = (struct kvm_io_range) {
4805		.addr = addr,
4806		.len = len,
4807	};
4808
4809	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4810	if (!bus)
4811		return -ENOMEM;
4812
4813	/* First try the device referenced by cookie. */
4814	if ((cookie >= 0) && (cookie < bus->dev_count) &&
4815	    (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
4816		if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
4817					val))
4818			return cookie;
4819
4820	/*
4821	 * cookie contained garbage; fall back to search and return the
4822	 * correct cookie value.
4823	 */
4824	return __kvm_io_bus_write(vcpu, bus, &range, val);
4825}
4826
4827static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
4828			     struct kvm_io_range *range, void *val)
4829{
4830	int idx;
4831
4832	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
4833	if (idx < 0)
4834		return -EOPNOTSUPP;
4835
4836	while (idx < bus->dev_count &&
4837		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
4838		if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
4839				       range->len, val))
4840			return idx;
4841		idx++;
4842	}
4843
4844	return -EOPNOTSUPP;
4845}
 
4846
4847/* kvm_io_bus_read - called under kvm->slots_lock */
4848int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
4849		    int len, void *val)
4850{
4851	struct kvm_io_bus *bus;
4852	struct kvm_io_range range;
4853	int r;
4854
4855	range = (struct kvm_io_range) {
4856		.addr = addr,
4857		.len = len,
4858	};
4859
4860	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4861	if (!bus)
4862		return -ENOMEM;
4863	r = __kvm_io_bus_read(vcpu, bus, &range, val);
4864	return r < 0 ? r : 0;
4865}
4866
 
4867/* Caller must hold slots_lock. */
4868int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
4869			    int len, struct kvm_io_device *dev)
4870{
4871	int i;
4872	struct kvm_io_bus *new_bus, *bus;
4873	struct kvm_io_range range;
4874
4875	bus = kvm_get_bus(kvm, bus_idx);
4876	if (!bus)
4877		return -ENOMEM;
4878
 
4879	/* exclude ioeventfd which is limited by maximum fd */
4880	if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
4881		return -ENOSPC;
4882
4883	new_bus = kmalloc(struct_size(bus, range, bus->dev_count + 1),
4884			  GFP_KERNEL_ACCOUNT);
4885	if (!new_bus)
4886		return -ENOMEM;
4887
4888	range = (struct kvm_io_range) {
4889		.addr = addr,
4890		.len = len,
4891		.dev = dev,
4892	};
4893
4894	for (i = 0; i < bus->dev_count; i++)
4895		if (kvm_io_bus_cmp(&bus->range[i], &range) > 0)
4896			break;
4897
4898	memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
4899	new_bus->dev_count++;
4900	new_bus->range[i] = range;
4901	memcpy(new_bus->range + i + 1, bus->range + i,
4902		(bus->dev_count - i) * sizeof(struct kvm_io_range));
4903	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
4904	synchronize_srcu_expedited(&kvm->srcu);
4905	kfree(bus);
4906
4907	return 0;
4908}
4909
 
4910int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
4911			      struct kvm_io_device *dev)
4912{
4913	int i, j;
4914	struct kvm_io_bus *new_bus, *bus;
4915
4916	lockdep_assert_held(&kvm->slots_lock);
4917
4918	bus = kvm_get_bus(kvm, bus_idx);
4919	if (!bus)
4920		return 0;
4921
4922	for (i = 0; i < bus->dev_count; i++) {
4923		if (bus->range[i].dev == dev) {
 
4924			break;
4925		}
4926	}
4927
4928	if (i == bus->dev_count)
4929		return 0;
 
 
 
 
 
4930
4931	new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1),
4932			  GFP_KERNEL_ACCOUNT);
4933	if (new_bus) {
4934		memcpy(new_bus, bus, struct_size(bus, range, i));
4935		new_bus->dev_count--;
4936		memcpy(new_bus->range + i, bus->range + i + 1,
4937				flex_array_size(new_bus, range, new_bus->dev_count - i));
4938	}
4939
4940	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
4941	synchronize_srcu_expedited(&kvm->srcu);
4942
4943	/* Destroy the old bus _after_ installing the (null) bus. */
4944	if (!new_bus) {
4945		pr_err("kvm: failed to shrink bus, removing it completely\n");
4946		for (j = 0; j < bus->dev_count; j++) {
4947			if (j == i)
4948				continue;
4949			kvm_iodevice_destructor(bus->range[j].dev);
4950		}
4951	}
4952
4953	kfree(bus);
4954	return new_bus ? 0 : -ENOMEM;
4955}
4956
4957struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
4958					 gpa_t addr)
4959{
4960	struct kvm_io_bus *bus;
4961	int dev_idx, srcu_idx;
4962	struct kvm_io_device *iodev = NULL;
4963
4964	srcu_idx = srcu_read_lock(&kvm->srcu);
4965
4966	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
4967	if (!bus)
4968		goto out_unlock;
4969
4970	dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1);
4971	if (dev_idx < 0)
4972		goto out_unlock;
4973
4974	iodev = bus->range[dev_idx].dev;
4975
4976out_unlock:
4977	srcu_read_unlock(&kvm->srcu, srcu_idx);
4978
4979	return iodev;
4980}
4981EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev);
4982
4983static int kvm_debugfs_open(struct inode *inode, struct file *file,
4984			   int (*get)(void *, u64 *), int (*set)(void *, u64),
4985			   const char *fmt)
4986{
4987	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
4988					  inode->i_private;
4989
4990	/* The debugfs files are a reference to the kvm struct which
4991	 * is still valid when kvm_destroy_vm is called.
4992	 * To avoid the race between open and the removal of the debugfs
4993	 * directory we test against the users count.
4994	 */
4995	if (!refcount_inc_not_zero(&stat_data->kvm->users_count))
4996		return -ENOENT;
4997
4998	if (simple_attr_open(inode, file, get,
4999		    kvm_stats_debugfs_mode(stat_data->desc) & 0222
5000		    ? set : NULL,
5001		    fmt)) {
5002		kvm_put_kvm(stat_data->kvm);
5003		return -ENOMEM;
5004	}
5005
5006	return 0;
5007}
5008
5009static int kvm_debugfs_release(struct inode *inode, struct file *file)
5010{
5011	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
5012					  inode->i_private;
5013
5014	simple_attr_release(inode, file);
5015	kvm_put_kvm(stat_data->kvm);
5016
5017	return 0;
5018}
5019
5020static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
5021{
5022	*val = *(u64 *)((void *)(&kvm->stat) + offset);
5023
5024	return 0;
5025}
5026
5027static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
5028{
5029	*(u64 *)((void *)(&kvm->stat) + offset) = 0;
5030
5031	return 0;
5032}
5033
5034static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
5035{
5036	int i;
5037	struct kvm_vcpu *vcpu;
5038
5039	*val = 0;
5040
5041	kvm_for_each_vcpu(i, vcpu, kvm)
5042		*val += *(u64 *)((void *)(&vcpu->stat) + offset);
5043
5044	return 0;
5045}
5046
5047static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
5048{
5049	int i;
5050	struct kvm_vcpu *vcpu;
5051
5052	kvm_for_each_vcpu(i, vcpu, kvm)
5053		*(u64 *)((void *)(&vcpu->stat) + offset) = 0;
5054
5055	return 0;
5056}
5057
5058static int kvm_stat_data_get(void *data, u64 *val)
5059{
5060	int r = -EFAULT;
5061	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
5062
5063	switch (stat_data->kind) {
5064	case KVM_STAT_VM:
5065		r = kvm_get_stat_per_vm(stat_data->kvm,
5066					stat_data->desc->desc.offset, val);
5067		break;
5068	case KVM_STAT_VCPU:
5069		r = kvm_get_stat_per_vcpu(stat_data->kvm,
5070					  stat_data->desc->desc.offset, val);
5071		break;
5072	}
5073
5074	return r;
5075}
5076
5077static int kvm_stat_data_clear(void *data, u64 val)
5078{
5079	int r = -EFAULT;
5080	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
5081
5082	if (val)
5083		return -EINVAL;
5084
5085	switch (stat_data->kind) {
5086	case KVM_STAT_VM:
5087		r = kvm_clear_stat_per_vm(stat_data->kvm,
5088					  stat_data->desc->desc.offset);
5089		break;
5090	case KVM_STAT_VCPU:
5091		r = kvm_clear_stat_per_vcpu(stat_data->kvm,
5092					    stat_data->desc->desc.offset);
5093		break;
5094	}
5095
5096	return r;
5097}
5098
5099static int kvm_stat_data_open(struct inode *inode, struct file *file)
5100{
5101	__simple_attr_check_format("%llu\n", 0ull);
5102	return kvm_debugfs_open(inode, file, kvm_stat_data_get,
5103				kvm_stat_data_clear, "%llu\n");
5104}
5105
5106static const struct file_operations stat_fops_per_vm = {
5107	.owner = THIS_MODULE,
5108	.open = kvm_stat_data_open,
5109	.release = kvm_debugfs_release,
5110	.read = simple_attr_read,
5111	.write = simple_attr_write,
5112	.llseek = no_llseek,
5113};
5114
5115static int vm_stat_get(void *_offset, u64 *val)
5116{
5117	unsigned offset = (long)_offset;
5118	struct kvm *kvm;
5119	u64 tmp_val;
5120
5121	*val = 0;
5122	mutex_lock(&kvm_lock);
5123	list_for_each_entry(kvm, &vm_list, vm_list) {
5124		kvm_get_stat_per_vm(kvm, offset, &tmp_val);
5125		*val += tmp_val;
5126	}
5127	mutex_unlock(&kvm_lock);
5128	return 0;
5129}
5130
5131static int vm_stat_clear(void *_offset, u64 val)
5132{
5133	unsigned offset = (long)_offset;
5134	struct kvm *kvm;
5135
5136	if (val)
5137		return -EINVAL;
5138
5139	mutex_lock(&kvm_lock);
5140	list_for_each_entry(kvm, &vm_list, vm_list) {
5141		kvm_clear_stat_per_vm(kvm, offset);
5142	}
5143	mutex_unlock(&kvm_lock);
5144
5145	return 0;
5146}
5147
5148DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, vm_stat_clear, "%llu\n");
5149DEFINE_SIMPLE_ATTRIBUTE(vm_stat_readonly_fops, vm_stat_get, NULL, "%llu\n");
5150
5151static int vcpu_stat_get(void *_offset, u64 *val)
5152{
5153	unsigned offset = (long)_offset;
5154	struct kvm *kvm;
5155	u64 tmp_val;
 
5156
5157	*val = 0;
5158	mutex_lock(&kvm_lock);
5159	list_for_each_entry(kvm, &vm_list, vm_list) {
5160		kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
5161		*val += tmp_val;
5162	}
5163	mutex_unlock(&kvm_lock);
5164	return 0;
5165}
5166
5167static int vcpu_stat_clear(void *_offset, u64 val)
5168{
5169	unsigned offset = (long)_offset;
5170	struct kvm *kvm;
5171
5172	if (val)
5173		return -EINVAL;
5174
5175	mutex_lock(&kvm_lock);
5176	list_for_each_entry(kvm, &vm_list, vm_list) {
5177		kvm_clear_stat_per_vcpu(kvm, offset);
5178	}
5179	mutex_unlock(&kvm_lock);
5180
5181	return 0;
5182}
5183
5184DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, vcpu_stat_clear,
5185			"%llu\n");
5186DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_readonly_fops, vcpu_stat_get, NULL, "%llu\n");
5187
5188static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
5189{
5190	struct kobj_uevent_env *env;
5191	unsigned long long created, active;
5192
5193	if (!kvm_dev.this_device || !kvm)
5194		return;
5195
5196	mutex_lock(&kvm_lock);
5197	if (type == KVM_EVENT_CREATE_VM) {
5198		kvm_createvm_count++;
5199		kvm_active_vms++;
5200	} else if (type == KVM_EVENT_DESTROY_VM) {
5201		kvm_active_vms--;
5202	}
5203	created = kvm_createvm_count;
5204	active = kvm_active_vms;
5205	mutex_unlock(&kvm_lock);
5206
5207	env = kzalloc(sizeof(*env), GFP_KERNEL_ACCOUNT);
5208	if (!env)
5209		return;
5210
5211	add_uevent_var(env, "CREATED=%llu", created);
5212	add_uevent_var(env, "COUNT=%llu", active);
5213
5214	if (type == KVM_EVENT_CREATE_VM) {
5215		add_uevent_var(env, "EVENT=create");
5216		kvm->userspace_pid = task_pid_nr(current);
5217	} else if (type == KVM_EVENT_DESTROY_VM) {
5218		add_uevent_var(env, "EVENT=destroy");
5219	}
5220	add_uevent_var(env, "PID=%d", kvm->userspace_pid);
5221
5222	if (kvm->debugfs_dentry) {
5223		char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL_ACCOUNT);
5224
5225		if (p) {
5226			tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX);
5227			if (!IS_ERR(tmp))
5228				add_uevent_var(env, "STATS_PATH=%s", tmp);
5229			kfree(p);
5230		}
5231	}
5232	/* no need for checks, since we are adding at most only 5 keys */
5233	env->envp[env->envp_idx++] = NULL;
5234	kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp);
5235	kfree(env);
5236}
5237
5238static void kvm_init_debug(void)
5239{
5240	const struct file_operations *fops;
5241	const struct _kvm_stats_desc *pdesc;
5242	int i;
5243
5244	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
5245
5246	for (i = 0; i < kvm_vm_stats_header.num_desc; ++i) {
5247		pdesc = &kvm_vm_stats_desc[i];
5248		if (kvm_stats_debugfs_mode(pdesc) & 0222)
5249			fops = &vm_stat_fops;
5250		else
5251			fops = &vm_stat_readonly_fops;
5252		debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
5253				kvm_debugfs_dir,
5254				(void *)(long)pdesc->desc.offset, fops);
5255	}
5256
5257	for (i = 0; i < kvm_vcpu_stats_header.num_desc; ++i) {
5258		pdesc = &kvm_vcpu_stats_desc[i];
5259		if (kvm_stats_debugfs_mode(pdesc) & 0222)
5260			fops = &vcpu_stat_fops;
5261		else
5262			fops = &vcpu_stat_readonly_fops;
5263		debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
5264				kvm_debugfs_dir,
5265				(void *)(long)pdesc->desc.offset, fops);
5266	}
5267}
5268
5269static int kvm_suspend(void)
5270{
5271	if (kvm_usage_count)
5272		hardware_disable_nolock(NULL);
5273	return 0;
5274}
5275
5276static void kvm_resume(void)
5277{
5278	if (kvm_usage_count) {
5279#ifdef CONFIG_LOCKDEP
5280		WARN_ON(lockdep_is_held(&kvm_count_lock));
5281#endif
5282		hardware_enable_nolock(NULL);
5283	}
5284}
5285
5286static struct syscore_ops kvm_syscore_ops = {
5287	.suspend = kvm_suspend,
5288	.resume = kvm_resume,
5289};
5290
5291static inline
5292struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
5293{
5294	return container_of(pn, struct kvm_vcpu, preempt_notifier);
5295}
5296
5297static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
5298{
5299	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
5300
5301	WRITE_ONCE(vcpu->preempted, false);
5302	WRITE_ONCE(vcpu->ready, false);
5303
5304	__this_cpu_write(kvm_running_vcpu, vcpu);
5305	kvm_arch_sched_in(vcpu, cpu);
 
5306	kvm_arch_vcpu_load(vcpu, cpu);
5307}
5308
5309static void kvm_sched_out(struct preempt_notifier *pn,
5310			  struct task_struct *next)
5311{
5312	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
5313
5314	if (current->on_rq) {
5315		WRITE_ONCE(vcpu->preempted, true);
5316		WRITE_ONCE(vcpu->ready, true);
5317	}
5318	kvm_arch_vcpu_put(vcpu);
5319	__this_cpu_write(kvm_running_vcpu, NULL);
5320}
5321
5322/**
5323 * kvm_get_running_vcpu - get the vcpu running on the current CPU.
5324 *
5325 * We can disable preemption locally around accessing the per-CPU variable,
5326 * and use the resolved vcpu pointer after enabling preemption again,
5327 * because even if the current thread is migrated to another CPU, reading
5328 * the per-CPU value later will give us the same value as we update the
5329 * per-CPU variable in the preempt notifier handlers.
5330 */
5331struct kvm_vcpu *kvm_get_running_vcpu(void)
5332{
5333	struct kvm_vcpu *vcpu;
5334
5335	preempt_disable();
5336	vcpu = __this_cpu_read(kvm_running_vcpu);
5337	preempt_enable();
5338
5339	return vcpu;
5340}
5341EXPORT_SYMBOL_GPL(kvm_get_running_vcpu);
5342
5343/**
5344 * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
5345 */
5346struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
5347{
5348        return &kvm_running_vcpu;
5349}
5350
5351struct kvm_cpu_compat_check {
5352	void *opaque;
5353	int *ret;
5354};
5355
5356static void check_processor_compat(void *data)
5357{
5358	struct kvm_cpu_compat_check *c = data;
5359
5360	*c->ret = kvm_arch_check_processor_compat(c->opaque);
5361}
5362
5363int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
5364		  struct module *module)
5365{
5366	struct kvm_cpu_compat_check c;
5367	int r;
5368	int cpu;
5369
5370	r = kvm_arch_init(opaque);
5371	if (r)
5372		goto out_fail;
5373
5374	/*
5375	 * kvm_arch_init makes sure there's at most one caller
5376	 * for architectures that support multiple implementations,
5377	 * like intel and amd on x86.
5378	 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
5379	 * conflicts in case kvm is already setup for another implementation.
5380	 */
5381	r = kvm_irqfd_init();
5382	if (r)
5383		goto out_irqfd;
5384
5385	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
5386		r = -ENOMEM;
5387		goto out_free_0;
5388	}
5389
5390	r = kvm_arch_hardware_setup(opaque);
5391	if (r < 0)
5392		goto out_free_1;
5393
5394	c.ret = &r;
5395	c.opaque = opaque;
5396	for_each_online_cpu(cpu) {
5397		smp_call_function_single(cpu, check_processor_compat, &c, 1);
 
 
5398		if (r < 0)
5399			goto out_free_2;
5400	}
5401
5402	r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "kvm/cpu:starting",
5403				      kvm_starting_cpu, kvm_dying_cpu);
5404	if (r)
5405		goto out_free_2;
5406	register_reboot_notifier(&kvm_reboot_notifier);
5407
5408	/* A kmem cache lets us meet the alignment requirements of fx_save. */
5409	if (!vcpu_align)
5410		vcpu_align = __alignof__(struct kvm_vcpu);
5411	kvm_vcpu_cache =
5412		kmem_cache_create_usercopy("kvm_vcpu", vcpu_size, vcpu_align,
5413					   SLAB_ACCOUNT,
5414					   offsetof(struct kvm_vcpu, arch),
5415					   offsetofend(struct kvm_vcpu, stats_id)
5416					   - offsetof(struct kvm_vcpu, arch),
5417					   NULL);
5418	if (!kvm_vcpu_cache) {
5419		r = -ENOMEM;
5420		goto out_free_3;
5421	}
5422
5423	r = kvm_async_pf_init();
5424	if (r)
5425		goto out_free;
5426
5427	kvm_chardev_ops.owner = module;
5428	kvm_vm_fops.owner = module;
5429	kvm_vcpu_fops.owner = module;
5430
5431	r = misc_register(&kvm_dev);
5432	if (r) {
5433		pr_err("kvm: misc device register failed\n");
5434		goto out_unreg;
5435	}
5436
5437	register_syscore_ops(&kvm_syscore_ops);
5438
5439	kvm_preempt_ops.sched_in = kvm_sched_in;
5440	kvm_preempt_ops.sched_out = kvm_sched_out;
5441
5442	kvm_init_debug();
 
 
 
 
5443
5444	r = kvm_vfio_ops_init();
5445	WARN_ON(r);
5446
5447	return 0;
5448
 
 
 
5449out_unreg:
5450	kvm_async_pf_deinit();
5451out_free:
5452	kmem_cache_destroy(kvm_vcpu_cache);
5453out_free_3:
5454	unregister_reboot_notifier(&kvm_reboot_notifier);
5455	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
5456out_free_2:
 
5457	kvm_arch_hardware_unsetup();
5458out_free_1:
5459	free_cpumask_var(cpus_hardware_enabled);
5460out_free_0:
5461	kvm_irqfd_exit();
5462out_irqfd:
5463	kvm_arch_exit();
5464out_fail:
5465	return r;
5466}
5467EXPORT_SYMBOL_GPL(kvm_init);
5468
5469void kvm_exit(void)
5470{
5471	debugfs_remove_recursive(kvm_debugfs_dir);
5472	misc_deregister(&kvm_dev);
5473	kmem_cache_destroy(kvm_vcpu_cache);
5474	kvm_async_pf_deinit();
5475	unregister_syscore_ops(&kvm_syscore_ops);
5476	unregister_reboot_notifier(&kvm_reboot_notifier);
5477	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
5478	on_each_cpu(hardware_disable_nolock, NULL, 1);
5479	kvm_arch_hardware_unsetup();
5480	kvm_arch_exit();
5481	kvm_irqfd_exit();
5482	free_cpumask_var(cpus_hardware_enabled);
5483	kvm_vfio_ops_exit();
5484}
5485EXPORT_SYMBOL_GPL(kvm_exit);
5486
5487struct kvm_vm_worker_thread_context {
5488	struct kvm *kvm;
5489	struct task_struct *parent;
5490	struct completion init_done;
5491	kvm_vm_thread_fn_t thread_fn;
5492	uintptr_t data;
5493	int err;
5494};
5495
5496static int kvm_vm_worker_thread(void *context)
5497{
5498	/*
5499	 * The init_context is allocated on the stack of the parent thread, so
5500	 * we have to locally copy anything that is needed beyond initialization
5501	 */
5502	struct kvm_vm_worker_thread_context *init_context = context;
5503	struct kvm *kvm = init_context->kvm;
5504	kvm_vm_thread_fn_t thread_fn = init_context->thread_fn;
5505	uintptr_t data = init_context->data;
5506	int err;
5507
5508	err = kthread_park(current);
5509	/* kthread_park(current) is never supposed to return an error */
5510	WARN_ON(err != 0);
5511	if (err)
5512		goto init_complete;
5513
5514	err = cgroup_attach_task_all(init_context->parent, current);
5515	if (err) {
5516		kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
5517			__func__, err);
5518		goto init_complete;
5519	}
5520
5521	set_user_nice(current, task_nice(init_context->parent));
5522
5523init_complete:
5524	init_context->err = err;
5525	complete(&init_context->init_done);
5526	init_context = NULL;
5527
5528	if (err)
5529		return err;
5530
5531	/* Wait to be woken up by the spawner before proceeding. */
5532	kthread_parkme();
5533
5534	if (!kthread_should_stop())
5535		err = thread_fn(kvm, data);
5536
5537	return err;
5538}
5539
5540int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
5541				uintptr_t data, const char *name,
5542				struct task_struct **thread_ptr)
5543{
5544	struct kvm_vm_worker_thread_context init_context = {};
5545	struct task_struct *thread;
5546
5547	*thread_ptr = NULL;
5548	init_context.kvm = kvm;
5549	init_context.parent = current;
5550	init_context.thread_fn = thread_fn;
5551	init_context.data = data;
5552	init_completion(&init_context.init_done);
5553
5554	thread = kthread_run(kvm_vm_worker_thread, &init_context,
5555			     "%s-%d", name, task_pid_nr(current));
5556	if (IS_ERR(thread))
5557		return PTR_ERR(thread);
5558
5559	/* kthread_run is never supposed to return NULL */
5560	WARN_ON(thread == NULL);
5561
5562	wait_for_completion(&init_context.init_done);
5563
5564	if (!init_context.err)
5565		*thread_ptr = thread;
5566
5567	return init_context.err;
5568}